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-rw-r--r--tools/testing/selftests/mm/.gitignore38
-rw-r--r--tools/testing/selftests/mm/Makefile185
-rw-r--r--tools/testing/selftests/mm/charge_reserved_hugetlb.sh584
-rw-r--r--tools/testing/selftests/mm/check_config.sh31
-rw-r--r--tools/testing/selftests/mm/compaction_test.c231
-rw-r--r--tools/testing/selftests/mm/config8
-rw-r--r--tools/testing/selftests/mm/cow.c1767
-rw-r--r--tools/testing/selftests/mm/gup_test.c271
-rw-r--r--tools/testing/selftests/mm/hmm-tests.c2054
-rw-r--r--tools/testing/selftests/mm/hugepage-mmap.c91
-rw-r--r--tools/testing/selftests/mm/hugepage-mremap.c188
-rw-r--r--tools/testing/selftests/mm/hugepage-shm.c101
-rw-r--r--tools/testing/selftests/mm/hugepage-vmemmap.c144
-rw-r--r--tools/testing/selftests/mm/hugetlb-madvise.c405
-rw-r--r--tools/testing/selftests/mm/hugetlb_reparenting_test.sh252
-rw-r--r--tools/testing/selftests/mm/khugepaged.c1558
-rw-r--r--tools/testing/selftests/mm/ksm_functional_tests.c279
-rw-r--r--tools/testing/selftests/mm/ksm_tests.c849
-rw-r--r--tools/testing/selftests/mm/madv_populate.c296
-rw-r--r--tools/testing/selftests/mm/map_fixed_noreplace.c231
-rw-r--r--tools/testing/selftests/mm/map_hugetlb.c109
-rw-r--r--tools/testing/selftests/mm/map_populate.c113
-rw-r--r--tools/testing/selftests/mm/mdwe_test.c197
-rw-r--r--tools/testing/selftests/mm/memfd_secret.c296
-rw-r--r--tools/testing/selftests/mm/migration.c193
-rw-r--r--tools/testing/selftests/mm/mlock-random-test.c294
-rw-r--r--tools/testing/selftests/mm/mlock2-tests.c520
-rw-r--r--tools/testing/selftests/mm/mlock2.h63
-rw-r--r--tools/testing/selftests/mm/mrelease_test.c206
-rw-r--r--tools/testing/selftests/mm/mremap_dontunmap.c364
-rw-r--r--tools/testing/selftests/mm/mremap_test.c548
-rw-r--r--tools/testing/selftests/mm/on-fault-limit.c48
-rw-r--r--tools/testing/selftests/mm/pkey-helpers.h226
-rw-r--r--tools/testing/selftests/mm/pkey-powerpc.h133
-rw-r--r--tools/testing/selftests/mm/pkey-x86.h177
-rw-r--r--tools/testing/selftests/mm/protection_keys.c1788
-rw-r--r--tools/testing/selftests/mm/run_vmtests.sh274
-rw-r--r--tools/testing/selftests/mm/settings1
-rw-r--r--tools/testing/selftests/mm/soft-dirty.c210
-rw-r--r--tools/testing/selftests/mm/split_huge_page_test.c309
-rw-r--r--tools/testing/selftests/mm/test_hmm.sh105
-rw-r--r--tools/testing/selftests/mm/test_vmalloc.sh177
-rw-r--r--tools/testing/selftests/mm/thuge-gen.c257
-rw-r--r--tools/testing/selftests/mm/transhuge-stress.c122
-rw-r--r--tools/testing/selftests/mm/userfaultfd.c1858
-rw-r--r--tools/testing/selftests/mm/util.h69
-rw-r--r--tools/testing/selftests/mm/va_128TBswitch.c289
-rw-r--r--tools/testing/selftests/mm/va_128TBswitch.sh54
-rw-r--r--tools/testing/selftests/mm/virtual_address_range.c139
-rw-r--r--tools/testing/selftests/mm/vm_util.c151
-rw-r--r--tools/testing/selftests/mm/vm_util.h15
-rw-r--r--tools/testing/selftests/mm/write_hugetlb_memory.sh23
-rw-r--r--tools/testing/selftests/mm/write_to_hugetlbfs.c240
53 files changed, 19131 insertions, 0 deletions
diff --git a/tools/testing/selftests/mm/.gitignore b/tools/testing/selftests/mm/.gitignore
new file mode 100644
index 000000000000..1f8c36a9fa10
--- /dev/null
+++ b/tools/testing/selftests/mm/.gitignore
@@ -0,0 +1,38 @@
+# SPDX-License-Identifier: GPL-2.0-only
+cow
+hugepage-mmap
+hugepage-mremap
+hugepage-shm
+hugepage-vmemmap
+hugetlb-madvise
+khugepaged
+map_hugetlb
+map_populate
+thuge-gen
+compaction_test
+migration
+mlock2-tests
+mrelease_test
+mremap_dontunmap
+mremap_test
+on-fault-limit
+transhuge-stress
+protection_keys
+protection_keys_32
+protection_keys_64
+madv_populate
+userfaultfd
+mlock-intersect-test
+mlock-random-test
+virtual_address_range
+gup_test
+va_128TBswitch
+map_fixed_noreplace
+write_to_hugetlbfs
+hmm-tests
+memfd_secret
+soft-dirty
+split_huge_page_test
+ksm_tests
+local_config.h
+local_config.mk
diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
new file mode 100644
index 000000000000..c31d952cff68
--- /dev/null
+++ b/tools/testing/selftests/mm/Makefile
@@ -0,0 +1,185 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for mm selftests
+
+LOCAL_HDRS += $(selfdir)/mm/local_config.h $(top_srcdir)/mm/gup_test.h
+
+include local_config.mk
+
+ifeq ($(CROSS_COMPILE),)
+uname_M := $(shell uname -m 2>/dev/null || echo not)
+else
+uname_M := $(shell echo $(CROSS_COMPILE) | grep -o '^[a-z0-9]\+')
+endif
+MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/' -e 's/ppc64.*/ppc64/')
+
+# Without this, failed build products remain, with up-to-date timestamps,
+# thus tricking Make (and you!) into believing that All Is Well, in subsequent
+# make invocations:
+.DELETE_ON_ERROR:
+
+# Avoid accidental wrong builds, due to built-in rules working just a little
+# bit too well--but not quite as well as required for our situation here.
+#
+# In other words, "make userfaultfd" is supposed to fail to build at all,
+# because this Makefile only supports either "make" (all), or "make /full/path".
+# However, the built-in rules, if not suppressed, will pick up CFLAGS and the
+# initial LDLIBS (but not the target-specific LDLIBS, because those are only
+# set for the full path target!). This causes it to get pretty far into building
+# things despite using incorrect values such as an *occasionally* incomplete
+# LDLIBS.
+MAKEFLAGS += --no-builtin-rules
+
+CFLAGS = -Wall -I $(top_srcdir) $(EXTRA_CFLAGS) $(KHDR_INCLUDES)
+LDLIBS = -lrt -lpthread
+TEST_GEN_FILES = cow
+TEST_GEN_FILES += compaction_test
+TEST_GEN_FILES += gup_test
+TEST_GEN_FILES += hmm-tests
+TEST_GEN_FILES += hugetlb-madvise
+TEST_GEN_FILES += hugepage-mmap
+TEST_GEN_FILES += hugepage-mremap
+TEST_GEN_FILES += hugepage-shm
+TEST_GEN_FILES += hugepage-vmemmap
+TEST_GEN_FILES += khugepaged
+TEST_GEN_PROGS = madv_populate
+TEST_GEN_FILES += map_fixed_noreplace
+TEST_GEN_FILES += map_hugetlb
+TEST_GEN_FILES += map_populate
+TEST_GEN_FILES += memfd_secret
+TEST_GEN_FILES += migration
+TEST_GEN_FILES += mlock-random-test
+TEST_GEN_FILES += mlock2-tests
+TEST_GEN_FILES += mrelease_test
+TEST_GEN_FILES += mremap_dontunmap
+TEST_GEN_FILES += mremap_test
+TEST_GEN_FILES += on-fault-limit
+TEST_GEN_FILES += thuge-gen
+TEST_GEN_FILES += transhuge-stress
+TEST_GEN_FILES += userfaultfd
+TEST_GEN_PROGS += soft-dirty
+TEST_GEN_PROGS += split_huge_page_test
+TEST_GEN_FILES += ksm_tests
+TEST_GEN_PROGS += ksm_functional_tests
+TEST_GEN_PROGS += mdwe_test
+
+ifeq ($(MACHINE),x86_64)
+CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh "$(CC)" ../x86/trivial_32bit_program.c -m32)
+CAN_BUILD_X86_64 := $(shell ./../x86/check_cc.sh "$(CC)" ../x86/trivial_64bit_program.c)
+CAN_BUILD_WITH_NOPIE := $(shell ./../x86/check_cc.sh "$(CC)" ../x86/trivial_program.c -no-pie)
+
+VMTARGETS := protection_keys
+BINARIES_32 := $(VMTARGETS:%=%_32)
+BINARIES_64 := $(VMTARGETS:%=%_64)
+
+ifeq ($(CAN_BUILD_WITH_NOPIE),1)
+CFLAGS += -no-pie
+endif
+
+ifeq ($(CAN_BUILD_I386),1)
+TEST_GEN_FILES += $(BINARIES_32)
+endif
+
+ifeq ($(CAN_BUILD_X86_64),1)
+TEST_GEN_FILES += $(BINARIES_64)
+endif
+else
+
+ifneq (,$(findstring $(MACHINE),ppc64))
+TEST_GEN_FILES += protection_keys
+endif
+
+endif
+
+ifneq (,$(filter $(MACHINE),arm64 ia64 mips64 parisc64 ppc64 riscv64 s390x sh64 sparc64 x86_64))
+TEST_GEN_FILES += va_128TBswitch
+TEST_GEN_FILES += virtual_address_range
+TEST_GEN_FILES += write_to_hugetlbfs
+endif
+
+TEST_PROGS := run_vmtests.sh
+
+TEST_FILES := test_vmalloc.sh
+TEST_FILES += test_hmm.sh
+TEST_FILES += va_128TBswitch.sh
+
+include ../lib.mk
+
+$(OUTPUT)/cow: vm_util.c
+$(OUTPUT)/khugepaged: vm_util.c
+$(OUTPUT)/ksm_functional_tests: vm_util.c
+$(OUTPUT)/madv_populate: vm_util.c
+$(OUTPUT)/soft-dirty: vm_util.c
+$(OUTPUT)/split_huge_page_test: vm_util.c
+$(OUTPUT)/userfaultfd: vm_util.c
+
+ifeq ($(MACHINE),x86_64)
+BINARIES_32 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_32))
+BINARIES_64 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_64))
+
+define gen-target-rule-32
+$(1) $(1)_32: $(OUTPUT)/$(1)_32
+.PHONY: $(1) $(1)_32
+endef
+
+define gen-target-rule-64
+$(1) $(1)_64: $(OUTPUT)/$(1)_64
+.PHONY: $(1) $(1)_64
+endef
+
+ifeq ($(CAN_BUILD_I386),1)
+$(BINARIES_32): CFLAGS += -m32 -mxsave
+$(BINARIES_32): LDLIBS += -lrt -ldl -lm
+$(BINARIES_32): $(OUTPUT)/%_32: %.c
+ $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@
+$(foreach t,$(VMTARGETS),$(eval $(call gen-target-rule-32,$(t))))
+endif
+
+ifeq ($(CAN_BUILD_X86_64),1)
+$(BINARIES_64): CFLAGS += -m64 -mxsave
+$(BINARIES_64): LDLIBS += -lrt -ldl
+$(BINARIES_64): $(OUTPUT)/%_64: %.c
+ $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $(notdir $^) $(LDLIBS) -o $@
+$(foreach t,$(VMTARGETS),$(eval $(call gen-target-rule-64,$(t))))
+endif
+
+# x86_64 users should be encouraged to install 32-bit libraries
+ifeq ($(CAN_BUILD_I386)$(CAN_BUILD_X86_64),01)
+all: warn_32bit_failure
+
+warn_32bit_failure:
+ @echo "Warning: you seem to have a broken 32-bit build" 2>&1; \
+ echo "environment. This will reduce test coverage of 64-bit" 2>&1; \
+ echo "kernels. If you are using a Debian-like distribution," 2>&1; \
+ echo "try:"; 2>&1; \
+ echo ""; \
+ echo " apt-get install gcc-multilib libc6-i386 libc6-dev-i386"; \
+ echo ""; \
+ echo "If you are using a Fedora-like distribution, try:"; \
+ echo ""; \
+ echo " yum install glibc-devel.*i686"; \
+ exit 0;
+endif
+endif
+
+# cow_EXTRA_LIBS may get set in local_config.mk, or it may be left empty.
+$(OUTPUT)/cow: LDLIBS += $(COW_EXTRA_LIBS)
+
+$(OUTPUT)/mlock-random-test $(OUTPUT)/memfd_secret: LDLIBS += -lcap
+
+$(OUTPUT)/ksm_tests: LDLIBS += -lnuma
+
+$(OUTPUT)/migration: LDLIBS += -lnuma
+
+local_config.mk local_config.h: check_config.sh
+ /bin/sh ./check_config.sh $(CC)
+
+EXTRA_CLEAN += local_config.mk local_config.h
+
+ifeq ($(COW_EXTRA_LIBS),)
+all: warn_missing_liburing
+
+warn_missing_liburing:
+ @echo ; \
+ echo "Warning: missing liburing support. Some COW tests will be skipped." ; \
+ echo
+endif
diff --git a/tools/testing/selftests/mm/charge_reserved_hugetlb.sh b/tools/testing/selftests/mm/charge_reserved_hugetlb.sh
new file mode 100644
index 000000000000..a5cb4b09a46c
--- /dev/null
+++ b/tools/testing/selftests/mm/charge_reserved_hugetlb.sh
@@ -0,0 +1,584 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+set -e
+
+if [[ $(id -u) -ne 0 ]]; then
+ echo "This test must be run as root. Skipping..."
+ exit $ksft_skip
+fi
+
+fault_limit_file=limit_in_bytes
+reservation_limit_file=rsvd.limit_in_bytes
+fault_usage_file=usage_in_bytes
+reservation_usage_file=rsvd.usage_in_bytes
+
+if [[ "$1" == "-cgroup-v2" ]]; then
+ cgroup2=1
+ fault_limit_file=max
+ reservation_limit_file=rsvd.max
+ fault_usage_file=current
+ reservation_usage_file=rsvd.current
+fi
+
+if [[ $cgroup2 ]]; then
+ cgroup_path=$(mount -t cgroup2 | head -1 | awk -e '{print $3}')
+ if [[ -z "$cgroup_path" ]]; then
+ cgroup_path=/dev/cgroup/memory
+ mount -t cgroup2 none $cgroup_path
+ do_umount=1
+ fi
+ echo "+hugetlb" >$cgroup_path/cgroup.subtree_control
+else
+ cgroup_path=$(mount -t cgroup | grep ",hugetlb" | awk -e '{print $3}')
+ if [[ -z "$cgroup_path" ]]; then
+ cgroup_path=/dev/cgroup/memory
+ mount -t cgroup memory,hugetlb $cgroup_path
+ do_umount=1
+ fi
+fi
+export cgroup_path
+
+function cleanup() {
+ if [[ $cgroup2 ]]; then
+ echo $$ >$cgroup_path/cgroup.procs
+ else
+ echo $$ >$cgroup_path/tasks
+ fi
+
+ if [[ -e /mnt/huge ]]; then
+ rm -rf /mnt/huge/*
+ umount /mnt/huge || echo error
+ rmdir /mnt/huge
+ fi
+ if [[ -e $cgroup_path/hugetlb_cgroup_test ]]; then
+ rmdir $cgroup_path/hugetlb_cgroup_test
+ fi
+ if [[ -e $cgroup_path/hugetlb_cgroup_test1 ]]; then
+ rmdir $cgroup_path/hugetlb_cgroup_test1
+ fi
+ if [[ -e $cgroup_path/hugetlb_cgroup_test2 ]]; then
+ rmdir $cgroup_path/hugetlb_cgroup_test2
+ fi
+ echo 0 >/proc/sys/vm/nr_hugepages
+ echo CLEANUP DONE
+}
+
+function expect_equal() {
+ local expected="$1"
+ local actual="$2"
+ local error="$3"
+
+ if [[ "$expected" != "$actual" ]]; then
+ echo "expected ($expected) != actual ($actual): $3"
+ cleanup
+ exit 1
+ fi
+}
+
+function get_machine_hugepage_size() {
+ hpz=$(grep -i hugepagesize /proc/meminfo)
+ kb=${hpz:14:-3}
+ mb=$(($kb / 1024))
+ echo $mb
+}
+
+MB=$(get_machine_hugepage_size)
+
+function setup_cgroup() {
+ local name="$1"
+ local cgroup_limit="$2"
+ local reservation_limit="$3"
+
+ mkdir $cgroup_path/$name
+
+ echo writing cgroup limit: "$cgroup_limit"
+ echo "$cgroup_limit" >$cgroup_path/$name/hugetlb.${MB}MB.$fault_limit_file
+
+ echo writing reseravation limit: "$reservation_limit"
+ echo "$reservation_limit" > \
+ $cgroup_path/$name/hugetlb.${MB}MB.$reservation_limit_file
+
+ if [ -e "$cgroup_path/$name/cpuset.cpus" ]; then
+ echo 0 >$cgroup_path/$name/cpuset.cpus
+ fi
+ if [ -e "$cgroup_path/$name/cpuset.mems" ]; then
+ echo 0 >$cgroup_path/$name/cpuset.mems
+ fi
+}
+
+function wait_for_hugetlb_memory_to_get_depleted() {
+ local cgroup="$1"
+ local path="$cgroup_path/$cgroup/hugetlb.${MB}MB.$reservation_usage_file"
+ # Wait for hugetlbfs memory to get depleted.
+ while [ $(cat $path) != 0 ]; do
+ echo Waiting for hugetlb memory to get depleted.
+ cat $path
+ sleep 0.5
+ done
+}
+
+function wait_for_hugetlb_memory_to_get_reserved() {
+ local cgroup="$1"
+ local size="$2"
+
+ local path="$cgroup_path/$cgroup/hugetlb.${MB}MB.$reservation_usage_file"
+ # Wait for hugetlbfs memory to get written.
+ while [ $(cat $path) != $size ]; do
+ echo Waiting for hugetlb memory reservation to reach size $size.
+ cat $path
+ sleep 0.5
+ done
+}
+
+function wait_for_hugetlb_memory_to_get_written() {
+ local cgroup="$1"
+ local size="$2"
+
+ local path="$cgroup_path/$cgroup/hugetlb.${MB}MB.$fault_usage_file"
+ # Wait for hugetlbfs memory to get written.
+ while [ $(cat $path) != $size ]; do
+ echo Waiting for hugetlb memory to reach size $size.
+ cat $path
+ sleep 0.5
+ done
+}
+
+function write_hugetlbfs_and_get_usage() {
+ local cgroup="$1"
+ local size="$2"
+ local populate="$3"
+ local write="$4"
+ local path="$5"
+ local method="$6"
+ local private="$7"
+ local expect_failure="$8"
+ local reserve="$9"
+
+ # Function return values.
+ reservation_failed=0
+ oom_killed=0
+ hugetlb_difference=0
+ reserved_difference=0
+
+ local hugetlb_usage=$cgroup_path/$cgroup/hugetlb.${MB}MB.$fault_usage_file
+ local reserved_usage=$cgroup_path/$cgroup/hugetlb.${MB}MB.$reservation_usage_file
+
+ local hugetlb_before=$(cat $hugetlb_usage)
+ local reserved_before=$(cat $reserved_usage)
+
+ echo
+ echo Starting:
+ echo hugetlb_usage="$hugetlb_before"
+ echo reserved_usage="$reserved_before"
+ echo expect_failure is "$expect_failure"
+
+ output=$(mktemp)
+ set +e
+ if [[ "$method" == "1" ]] || [[ "$method" == 2 ]] ||
+ [[ "$private" == "-r" ]] && [[ "$expect_failure" != 1 ]]; then
+
+ bash write_hugetlb_memory.sh "$size" "$populate" "$write" \
+ "$cgroup" "$path" "$method" "$private" "-l" "$reserve" 2>&1 | tee $output &
+
+ local write_result=$?
+ local write_pid=$!
+
+ until grep -q -i "DONE" $output; do
+ echo waiting for DONE signal.
+ if ! ps $write_pid > /dev/null
+ then
+ echo "FAIL: The write died"
+ cleanup
+ exit 1
+ fi
+ sleep 0.5
+ done
+
+ echo ================= write_hugetlb_memory.sh output is:
+ cat $output
+ echo ================= end output.
+
+ if [[ "$populate" == "-o" ]] || [[ "$write" == "-w" ]]; then
+ wait_for_hugetlb_memory_to_get_written "$cgroup" "$size"
+ elif [[ "$reserve" != "-n" ]]; then
+ wait_for_hugetlb_memory_to_get_reserved "$cgroup" "$size"
+ else
+ # This case doesn't produce visible effects, but we still have
+ # to wait for the async process to start and execute...
+ sleep 0.5
+ fi
+
+ echo write_result is $write_result
+ else
+ bash write_hugetlb_memory.sh "$size" "$populate" "$write" \
+ "$cgroup" "$path" "$method" "$private" "$reserve"
+ local write_result=$?
+
+ if [[ "$reserve" != "-n" ]]; then
+ wait_for_hugetlb_memory_to_get_reserved "$cgroup" "$size"
+ fi
+ fi
+ set -e
+
+ if [[ "$write_result" == 1 ]]; then
+ reservation_failed=1
+ fi
+
+ # On linus/master, the above process gets SIGBUS'd on oomkill, with
+ # return code 135. On earlier kernels, it gets actual oomkill, with return
+ # code 137, so just check for both conditions in case we're testing
+ # against an earlier kernel.
+ if [[ "$write_result" == 135 ]] || [[ "$write_result" == 137 ]]; then
+ oom_killed=1
+ fi
+
+ local hugetlb_after=$(cat $hugetlb_usage)
+ local reserved_after=$(cat $reserved_usage)
+
+ echo After write:
+ echo hugetlb_usage="$hugetlb_after"
+ echo reserved_usage="$reserved_after"
+
+ hugetlb_difference=$(($hugetlb_after - $hugetlb_before))
+ reserved_difference=$(($reserved_after - $reserved_before))
+}
+
+function cleanup_hugetlb_memory() {
+ set +e
+ local cgroup="$1"
+ if [[ "$(pgrep -f write_to_hugetlbfs)" != "" ]]; then
+ echo killing write_to_hugetlbfs
+ killall -2 write_to_hugetlbfs
+ wait_for_hugetlb_memory_to_get_depleted $cgroup
+ fi
+ set -e
+
+ if [[ -e /mnt/huge ]]; then
+ rm -rf /mnt/huge/*
+ umount /mnt/huge
+ rmdir /mnt/huge
+ fi
+}
+
+function run_test() {
+ local size=$(($1 * ${MB} * 1024 * 1024))
+ local populate="$2"
+ local write="$3"
+ local cgroup_limit=$(($4 * ${MB} * 1024 * 1024))
+ local reservation_limit=$(($5 * ${MB} * 1024 * 1024))
+ local nr_hugepages="$6"
+ local method="$7"
+ local private="$8"
+ local expect_failure="$9"
+ local reserve="${10}"
+
+ # Function return values.
+ hugetlb_difference=0
+ reserved_difference=0
+ reservation_failed=0
+ oom_killed=0
+
+ echo nr hugepages = "$nr_hugepages"
+ echo "$nr_hugepages" >/proc/sys/vm/nr_hugepages
+
+ setup_cgroup "hugetlb_cgroup_test" "$cgroup_limit" "$reservation_limit"
+
+ mkdir -p /mnt/huge
+ mount -t hugetlbfs -o pagesize=${MB}M,size=256M none /mnt/huge
+
+ write_hugetlbfs_and_get_usage "hugetlb_cgroup_test" "$size" "$populate" \
+ "$write" "/mnt/huge/test" "$method" "$private" "$expect_failure" \
+ "$reserve"
+
+ cleanup_hugetlb_memory "hugetlb_cgroup_test"
+
+ local final_hugetlb=$(cat $cgroup_path/hugetlb_cgroup_test/hugetlb.${MB}MB.$fault_usage_file)
+ local final_reservation=$(cat $cgroup_path/hugetlb_cgroup_test/hugetlb.${MB}MB.$reservation_usage_file)
+
+ echo $hugetlb_difference
+ echo $reserved_difference
+ expect_equal "0" "$final_hugetlb" "final hugetlb is not zero"
+ expect_equal "0" "$final_reservation" "final reservation is not zero"
+}
+
+function run_multiple_cgroup_test() {
+ local size1="$1"
+ local populate1="$2"
+ local write1="$3"
+ local cgroup_limit1="$4"
+ local reservation_limit1="$5"
+
+ local size2="$6"
+ local populate2="$7"
+ local write2="$8"
+ local cgroup_limit2="$9"
+ local reservation_limit2="${10}"
+
+ local nr_hugepages="${11}"
+ local method="${12}"
+ local private="${13}"
+ local expect_failure="${14}"
+ local reserve="${15}"
+
+ # Function return values.
+ hugetlb_difference1=0
+ reserved_difference1=0
+ reservation_failed1=0
+ oom_killed1=0
+
+ hugetlb_difference2=0
+ reserved_difference2=0
+ reservation_failed2=0
+ oom_killed2=0
+
+ echo nr hugepages = "$nr_hugepages"
+ echo "$nr_hugepages" >/proc/sys/vm/nr_hugepages
+
+ setup_cgroup "hugetlb_cgroup_test1" "$cgroup_limit1" "$reservation_limit1"
+ setup_cgroup "hugetlb_cgroup_test2" "$cgroup_limit2" "$reservation_limit2"
+
+ mkdir -p /mnt/huge
+ mount -t hugetlbfs -o pagesize=${MB}M,size=256M none /mnt/huge
+
+ write_hugetlbfs_and_get_usage "hugetlb_cgroup_test1" "$size1" \
+ "$populate1" "$write1" "/mnt/huge/test1" "$method" "$private" \
+ "$expect_failure" "$reserve"
+
+ hugetlb_difference1=$hugetlb_difference
+ reserved_difference1=$reserved_difference
+ reservation_failed1=$reservation_failed
+ oom_killed1=$oom_killed
+
+ local cgroup1_hugetlb_usage=$cgroup_path/hugetlb_cgroup_test1/hugetlb.${MB}MB.$fault_usage_file
+ local cgroup1_reservation_usage=$cgroup_path/hugetlb_cgroup_test1/hugetlb.${MB}MB.$reservation_usage_file
+ local cgroup2_hugetlb_usage=$cgroup_path/hugetlb_cgroup_test2/hugetlb.${MB}MB.$fault_usage_file
+ local cgroup2_reservation_usage=$cgroup_path/hugetlb_cgroup_test2/hugetlb.${MB}MB.$reservation_usage_file
+
+ local usage_before_second_write=$(cat $cgroup1_hugetlb_usage)
+ local reservation_usage_before_second_write=$(cat $cgroup1_reservation_usage)
+
+ write_hugetlbfs_and_get_usage "hugetlb_cgroup_test2" "$size2" \
+ "$populate2" "$write2" "/mnt/huge/test2" "$method" "$private" \
+ "$expect_failure" "$reserve"
+
+ hugetlb_difference2=$hugetlb_difference
+ reserved_difference2=$reserved_difference
+ reservation_failed2=$reservation_failed
+ oom_killed2=$oom_killed
+
+ expect_equal "$usage_before_second_write" \
+ "$(cat $cgroup1_hugetlb_usage)" "Usage changed."
+ expect_equal "$reservation_usage_before_second_write" \
+ "$(cat $cgroup1_reservation_usage)" "Reservation usage changed."
+
+ cleanup_hugetlb_memory
+
+ local final_hugetlb=$(cat $cgroup1_hugetlb_usage)
+ local final_reservation=$(cat $cgroup1_reservation_usage)
+
+ expect_equal "0" "$final_hugetlb" \
+ "hugetlbt_cgroup_test1 final hugetlb is not zero"
+ expect_equal "0" "$final_reservation" \
+ "hugetlbt_cgroup_test1 final reservation is not zero"
+
+ local final_hugetlb=$(cat $cgroup2_hugetlb_usage)
+ local final_reservation=$(cat $cgroup2_reservation_usage)
+
+ expect_equal "0" "$final_hugetlb" \
+ "hugetlb_cgroup_test2 final hugetlb is not zero"
+ expect_equal "0" "$final_reservation" \
+ "hugetlb_cgroup_test2 final reservation is not zero"
+}
+
+cleanup
+
+for populate in "" "-o"; do
+ for method in 0 1 2; do
+ for private in "" "-r"; do
+ for reserve in "" "-n"; do
+
+ # Skip mmap(MAP_HUGETLB | MAP_SHARED). Doesn't seem to be supported.
+ if [[ "$method" == 1 ]] && [[ "$private" == "" ]]; then
+ continue
+ fi
+
+ # Skip populated shmem tests. Doesn't seem to be supported.
+ if [[ "$method" == 2"" ]] && [[ "$populate" == "-o" ]]; then
+ continue
+ fi
+
+ if [[ "$method" == 2"" ]] && [[ "$reserve" == "-n" ]]; then
+ continue
+ fi
+
+ cleanup
+ echo
+ echo
+ echo
+ echo Test normal case.
+ echo private=$private, populate=$populate, method=$method, reserve=$reserve
+ run_test 5 "$populate" "" 10 10 10 "$method" "$private" "0" "$reserve"
+
+ echo Memory charged to hugtlb=$hugetlb_difference
+ echo Memory charged to reservation=$reserved_difference
+
+ if [[ "$populate" == "-o" ]]; then
+ expect_equal "$((5 * $MB * 1024 * 1024))" "$hugetlb_difference" \
+ "Reserved memory charged to hugetlb cgroup."
+ else
+ expect_equal "0" "$hugetlb_difference" \
+ "Reserved memory charged to hugetlb cgroup."
+ fi
+
+ if [[ "$reserve" != "-n" ]] || [[ "$populate" == "-o" ]]; then
+ expect_equal "$((5 * $MB * 1024 * 1024))" "$reserved_difference" \
+ "Reserved memory not charged to reservation usage."
+ else
+ expect_equal "0" "$reserved_difference" \
+ "Reserved memory not charged to reservation usage."
+ fi
+
+ echo 'PASS'
+
+ cleanup
+ echo
+ echo
+ echo
+ echo Test normal case with write.
+ echo private=$private, populate=$populate, method=$method, reserve=$reserve
+ run_test 5 "$populate" '-w' 5 5 10 "$method" "$private" "0" "$reserve"
+
+ echo Memory charged to hugtlb=$hugetlb_difference
+ echo Memory charged to reservation=$reserved_difference
+
+ expect_equal "$((5 * $MB * 1024 * 1024))" "$hugetlb_difference" \
+ "Reserved memory charged to hugetlb cgroup."
+
+ expect_equal "$((5 * $MB * 1024 * 1024))" "$reserved_difference" \
+ "Reserved memory not charged to reservation usage."
+
+ echo 'PASS'
+
+ cleanup
+ continue
+ echo
+ echo
+ echo
+ echo Test more than reservation case.
+ echo private=$private, populate=$populate, method=$method, reserve=$reserve
+
+ if [ "$reserve" != "-n" ]; then
+ run_test "5" "$populate" '' "10" "2" "10" "$method" "$private" "1" \
+ "$reserve"
+
+ expect_equal "1" "$reservation_failed" "Reservation succeeded."
+ fi
+
+ echo 'PASS'
+
+ cleanup
+
+ echo
+ echo
+ echo
+ echo Test more than cgroup limit case.
+ echo private=$private, populate=$populate, method=$method, reserve=$reserve
+
+ # Not sure if shm memory can be cleaned up when the process gets sigbus'd.
+ if [[ "$method" != 2 ]]; then
+ run_test 5 "$populate" "-w" 2 10 10 "$method" "$private" "1" "$reserve"
+
+ expect_equal "1" "$oom_killed" "Not oom killed."
+ fi
+ echo 'PASS'
+
+ cleanup
+
+ echo
+ echo
+ echo
+ echo Test normal case, multiple cgroups.
+ echo private=$private, populate=$populate, method=$method, reserve=$reserve
+ run_multiple_cgroup_test "3" "$populate" "" "10" "10" "5" \
+ "$populate" "" "10" "10" "10" \
+ "$method" "$private" "0" "$reserve"
+
+ echo Memory charged to hugtlb1=$hugetlb_difference1
+ echo Memory charged to reservation1=$reserved_difference1
+ echo Memory charged to hugtlb2=$hugetlb_difference2
+ echo Memory charged to reservation2=$reserved_difference2
+
+ if [[ "$reserve" != "-n" ]] || [[ "$populate" == "-o" ]]; then
+ expect_equal "3" "$reserved_difference1" \
+ "Incorrect reservations charged to cgroup 1."
+
+ expect_equal "5" "$reserved_difference2" \
+ "Incorrect reservation charged to cgroup 2."
+
+ else
+ expect_equal "0" "$reserved_difference1" \
+ "Incorrect reservations charged to cgroup 1."
+
+ expect_equal "0" "$reserved_difference2" \
+ "Incorrect reservation charged to cgroup 2."
+ fi
+
+ if [[ "$populate" == "-o" ]]; then
+ expect_equal "3" "$hugetlb_difference1" \
+ "Incorrect hugetlb charged to cgroup 1."
+
+ expect_equal "5" "$hugetlb_difference2" \
+ "Incorrect hugetlb charged to cgroup 2."
+
+ else
+ expect_equal "0" "$hugetlb_difference1" \
+ "Incorrect hugetlb charged to cgroup 1."
+
+ expect_equal "0" "$hugetlb_difference2" \
+ "Incorrect hugetlb charged to cgroup 2."
+ fi
+ echo 'PASS'
+
+ cleanup
+ echo
+ echo
+ echo
+ echo Test normal case with write, multiple cgroups.
+ echo private=$private, populate=$populate, method=$method, reserve=$reserve
+ run_multiple_cgroup_test "3" "$populate" "-w" "10" "10" "5" \
+ "$populate" "-w" "10" "10" "10" \
+ "$method" "$private" "0" "$reserve"
+
+ echo Memory charged to hugtlb1=$hugetlb_difference1
+ echo Memory charged to reservation1=$reserved_difference1
+ echo Memory charged to hugtlb2=$hugetlb_difference2
+ echo Memory charged to reservation2=$reserved_difference2
+
+ expect_equal "3" "$hugetlb_difference1" \
+ "Incorrect hugetlb charged to cgroup 1."
+
+ expect_equal "3" "$reserved_difference1" \
+ "Incorrect reservation charged to cgroup 1."
+
+ expect_equal "5" "$hugetlb_difference2" \
+ "Incorrect hugetlb charged to cgroup 2."
+
+ expect_equal "5" "$reserved_difference2" \
+ "Incorrected reservation charged to cgroup 2."
+ echo 'PASS'
+
+ cleanup
+
+ done # reserve
+ done # private
+ done # populate
+done # method
+
+if [[ $do_umount ]]; then
+ umount $cgroup_path
+ rmdir $cgroup_path
+fi
diff --git a/tools/testing/selftests/mm/check_config.sh b/tools/testing/selftests/mm/check_config.sh
new file mode 100644
index 000000000000..bcba3af0acea
--- /dev/null
+++ b/tools/testing/selftests/mm/check_config.sh
@@ -0,0 +1,31 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Probe for libraries and create header files to record the results. Both C
+# header files and Makefile include fragments are created.
+
+OUTPUT_H_FILE=local_config.h
+OUTPUT_MKFILE=local_config.mk
+
+tmpname=$(mktemp)
+tmpfile_c=${tmpname}.c
+tmpfile_o=${tmpname}.o
+
+# liburing
+echo "#include <sys/types.h>" > $tmpfile_c
+echo "#include <liburing.h>" >> $tmpfile_c
+echo "int func(void) { return 0; }" >> $tmpfile_c
+
+CC=${1:?"Usage: $0 <compiler> # example compiler: gcc"}
+$CC -c $tmpfile_c -o $tmpfile_o >/dev/null 2>&1
+
+if [ -f $tmpfile_o ]; then
+ echo "#define LOCAL_CONFIG_HAVE_LIBURING 1" > $OUTPUT_H_FILE
+ echo "COW_EXTRA_LIBS = -luring" > $OUTPUT_MKFILE
+else
+ echo "// No liburing support found" > $OUTPUT_H_FILE
+ echo "# No liburing support found, so:" > $OUTPUT_MKFILE
+ echo "COW_EXTRA_LIBS = " >> $OUTPUT_MKFILE
+fi
+
+rm ${tmpname}.*
diff --git a/tools/testing/selftests/mm/compaction_test.c b/tools/testing/selftests/mm/compaction_test.c
new file mode 100644
index 000000000000..9b420140ba2b
--- /dev/null
+++ b/tools/testing/selftests/mm/compaction_test.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *
+ * A test for the patch "Allow compaction of unevictable pages".
+ * With this patch we should be able to allocate at least 1/4
+ * of RAM in huge pages. Without the patch much less is
+ * allocated.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+
+#include "../kselftest.h"
+
+#define MAP_SIZE_MB 100
+#define MAP_SIZE (MAP_SIZE_MB * 1024 * 1024)
+
+struct map_list {
+ void *map;
+ struct map_list *next;
+};
+
+int read_memory_info(unsigned long *memfree, unsigned long *hugepagesize)
+{
+ char buffer[256] = {0};
+ char *cmd = "cat /proc/meminfo | grep -i memfree | grep -o '[0-9]*'";
+ FILE *cmdfile = popen(cmd, "r");
+
+ if (!(fgets(buffer, sizeof(buffer), cmdfile))) {
+ perror("Failed to read meminfo\n");
+ return -1;
+ }
+
+ pclose(cmdfile);
+
+ *memfree = atoll(buffer);
+ cmd = "cat /proc/meminfo | grep -i hugepagesize | grep -o '[0-9]*'";
+ cmdfile = popen(cmd, "r");
+
+ if (!(fgets(buffer, sizeof(buffer), cmdfile))) {
+ perror("Failed to read meminfo\n");
+ return -1;
+ }
+
+ pclose(cmdfile);
+ *hugepagesize = atoll(buffer);
+
+ return 0;
+}
+
+int prereq(void)
+{
+ char allowed;
+ int fd;
+
+ fd = open("/proc/sys/vm/compact_unevictable_allowed",
+ O_RDONLY | O_NONBLOCK);
+ if (fd < 0) {
+ perror("Failed to open\n"
+ "/proc/sys/vm/compact_unevictable_allowed\n");
+ return -1;
+ }
+
+ if (read(fd, &allowed, sizeof(char)) != sizeof(char)) {
+ perror("Failed to read from\n"
+ "/proc/sys/vm/compact_unevictable_allowed\n");
+ close(fd);
+ return -1;
+ }
+
+ close(fd);
+ if (allowed == '1')
+ return 0;
+
+ return -1;
+}
+
+int check_compaction(unsigned long mem_free, unsigned int hugepage_size)
+{
+ int fd;
+ int compaction_index = 0;
+ char initial_nr_hugepages[10] = {0};
+ char nr_hugepages[10] = {0};
+
+ /* We want to test with 80% of available memory. Else, OOM killer comes
+ in to play */
+ mem_free = mem_free * 0.8;
+
+ fd = open("/proc/sys/vm/nr_hugepages", O_RDWR | O_NONBLOCK);
+ if (fd < 0) {
+ perror("Failed to open /proc/sys/vm/nr_hugepages");
+ return -1;
+ }
+
+ if (read(fd, initial_nr_hugepages, sizeof(initial_nr_hugepages)) <= 0) {
+ perror("Failed to read from /proc/sys/vm/nr_hugepages");
+ goto close_fd;
+ }
+
+ /* Start with the initial condition of 0 huge pages*/
+ if (write(fd, "0", sizeof(char)) != sizeof(char)) {
+ perror("Failed to write 0 to /proc/sys/vm/nr_hugepages\n");
+ goto close_fd;
+ }
+
+ lseek(fd, 0, SEEK_SET);
+
+ /* Request a large number of huge pages. The Kernel will allocate
+ as much as it can */
+ if (write(fd, "100000", (6*sizeof(char))) != (6*sizeof(char))) {
+ perror("Failed to write 100000 to /proc/sys/vm/nr_hugepages\n");
+ goto close_fd;
+ }
+
+ lseek(fd, 0, SEEK_SET);
+
+ if (read(fd, nr_hugepages, sizeof(nr_hugepages)) <= 0) {
+ perror("Failed to re-read from /proc/sys/vm/nr_hugepages\n");
+ goto close_fd;
+ }
+
+ /* We should have been able to request at least 1/3 rd of the memory in
+ huge pages */
+ compaction_index = mem_free/(atoi(nr_hugepages) * hugepage_size);
+
+ if (compaction_index > 3) {
+ printf("No of huge pages allocated = %d\n",
+ (atoi(nr_hugepages)));
+ fprintf(stderr, "ERROR: Less that 1/%d of memory is available\n"
+ "as huge pages\n", compaction_index);
+ goto close_fd;
+ }
+
+ printf("No of huge pages allocated = %d\n",
+ (atoi(nr_hugepages)));
+
+ lseek(fd, 0, SEEK_SET);
+
+ if (write(fd, initial_nr_hugepages, strlen(initial_nr_hugepages))
+ != strlen(initial_nr_hugepages)) {
+ perror("Failed to write value to /proc/sys/vm/nr_hugepages\n");
+ goto close_fd;
+ }
+
+ close(fd);
+ return 0;
+
+ close_fd:
+ close(fd);
+ printf("Not OK. Compaction test failed.");
+ return -1;
+}
+
+
+int main(int argc, char **argv)
+{
+ struct rlimit lim;
+ struct map_list *list, *entry;
+ size_t page_size, i;
+ void *map = NULL;
+ unsigned long mem_free = 0;
+ unsigned long hugepage_size = 0;
+ long mem_fragmentable_MB = 0;
+
+ if (prereq() != 0) {
+ printf("Either the sysctl compact_unevictable_allowed is not\n"
+ "set to 1 or couldn't read the proc file.\n"
+ "Skipping the test\n");
+ return KSFT_SKIP;
+ }
+
+ lim.rlim_cur = RLIM_INFINITY;
+ lim.rlim_max = RLIM_INFINITY;
+ if (setrlimit(RLIMIT_MEMLOCK, &lim)) {
+ perror("Failed to set rlimit:\n");
+ return -1;
+ }
+
+ page_size = getpagesize();
+
+ list = NULL;
+
+ if (read_memory_info(&mem_free, &hugepage_size) != 0) {
+ printf("ERROR: Cannot read meminfo\n");
+ return -1;
+ }
+
+ mem_fragmentable_MB = mem_free * 0.8 / 1024;
+
+ while (mem_fragmentable_MB > 0) {
+ map = mmap(NULL, MAP_SIZE, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE | MAP_LOCKED, -1, 0);
+ if (map == MAP_FAILED)
+ break;
+
+ entry = malloc(sizeof(struct map_list));
+ if (!entry) {
+ munmap(map, MAP_SIZE);
+ break;
+ }
+ entry->map = map;
+ entry->next = list;
+ list = entry;
+
+ /* Write something (in this case the address of the map) to
+ * ensure that KSM can't merge the mapped pages
+ */
+ for (i = 0; i < MAP_SIZE; i += page_size)
+ *(unsigned long *)(map + i) = (unsigned long)map + i;
+
+ mem_fragmentable_MB -= MAP_SIZE_MB;
+ }
+
+ for (entry = list; entry != NULL; entry = entry->next) {
+ munmap(entry->map, MAP_SIZE);
+ if (!entry->next)
+ break;
+ entry = entry->next;
+ }
+
+ if (check_compaction(mem_free, hugepage_size) == 0)
+ return 0;
+
+ return -1;
+}
diff --git a/tools/testing/selftests/mm/config b/tools/testing/selftests/mm/config
new file mode 100644
index 000000000000..be087c4bc396
--- /dev/null
+++ b/tools/testing/selftests/mm/config
@@ -0,0 +1,8 @@
+CONFIG_SYSVIPC=y
+CONFIG_USERFAULTFD=y
+CONFIG_TEST_VMALLOC=m
+CONFIG_DEVICE_PRIVATE=y
+CONFIG_TEST_HMM=m
+CONFIG_GUP_TEST=y
+CONFIG_TRANSPARENT_HUGEPAGE=y
+CONFIG_MEM_SOFT_DIRTY=y
diff --git a/tools/testing/selftests/mm/cow.c b/tools/testing/selftests/mm/cow.c
new file mode 100644
index 000000000000..0eb2e8180aa5
--- /dev/null
+++ b/tools/testing/selftests/mm/cow.c
@@ -0,0 +1,1767 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * COW (Copy On Write) tests.
+ *
+ * Copyright 2022, Red Hat, Inc.
+ *
+ * Author(s): David Hildenbrand <david@redhat.com>
+ */
+#define _GNU_SOURCE
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <assert.h>
+#include <sys/mman.h>
+#include <sys/ioctl.h>
+#include <sys/wait.h>
+#include <linux/memfd.h>
+
+#include "local_config.h"
+#ifdef LOCAL_CONFIG_HAVE_LIBURING
+#include <liburing.h>
+#endif /* LOCAL_CONFIG_HAVE_LIBURING */
+
+#include "../../../../mm/gup_test.h"
+#include "../kselftest.h"
+#include "vm_util.h"
+
+#ifndef MADV_PAGEOUT
+#define MADV_PAGEOUT 21
+#endif
+#ifndef MADV_COLLAPSE
+#define MADV_COLLAPSE 25
+#endif
+
+static size_t pagesize;
+static int pagemap_fd;
+static size_t thpsize;
+static int nr_hugetlbsizes;
+static size_t hugetlbsizes[10];
+static int gup_fd;
+static bool has_huge_zeropage;
+
+static void detect_thpsize(void)
+{
+ int fd = open("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size",
+ O_RDONLY);
+ size_t size = 0;
+ char buf[15];
+ int ret;
+
+ if (fd < 0)
+ return;
+
+ ret = pread(fd, buf, sizeof(buf), 0);
+ if (ret > 0 && ret < sizeof(buf)) {
+ buf[ret] = 0;
+
+ size = strtoul(buf, NULL, 10);
+ if (size < pagesize)
+ size = 0;
+ if (size > 0) {
+ thpsize = size;
+ ksft_print_msg("[INFO] detected THP size: %zu KiB\n",
+ thpsize / 1024);
+ }
+ }
+
+ close(fd);
+}
+
+static void detect_huge_zeropage(void)
+{
+ int fd = open("/sys/kernel/mm/transparent_hugepage/use_zero_page",
+ O_RDONLY);
+ size_t enabled = 0;
+ char buf[15];
+ int ret;
+
+ if (fd < 0)
+ return;
+
+ ret = pread(fd, buf, sizeof(buf), 0);
+ if (ret > 0 && ret < sizeof(buf)) {
+ buf[ret] = 0;
+
+ enabled = strtoul(buf, NULL, 10);
+ if (enabled == 1) {
+ has_huge_zeropage = true;
+ ksft_print_msg("[INFO] huge zeropage is enabled\n");
+ }
+ }
+
+ close(fd);
+}
+
+static void detect_hugetlbsizes(void)
+{
+ DIR *dir = opendir("/sys/kernel/mm/hugepages/");
+
+ if (!dir)
+ return;
+
+ while (nr_hugetlbsizes < ARRAY_SIZE(hugetlbsizes)) {
+ struct dirent *entry = readdir(dir);
+ size_t kb;
+
+ if (!entry)
+ break;
+ if (entry->d_type != DT_DIR)
+ continue;
+ if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1)
+ continue;
+ hugetlbsizes[nr_hugetlbsizes] = kb * 1024;
+ nr_hugetlbsizes++;
+ ksft_print_msg("[INFO] detected hugetlb size: %zu KiB\n",
+ kb);
+ }
+ closedir(dir);
+}
+
+static bool range_is_swapped(void *addr, size_t size)
+{
+ for (; size; addr += pagesize, size -= pagesize)
+ if (!pagemap_is_swapped(pagemap_fd, addr))
+ return false;
+ return true;
+}
+
+struct comm_pipes {
+ int child_ready[2];
+ int parent_ready[2];
+};
+
+static int setup_comm_pipes(struct comm_pipes *comm_pipes)
+{
+ if (pipe(comm_pipes->child_ready) < 0)
+ return -errno;
+ if (pipe(comm_pipes->parent_ready) < 0) {
+ close(comm_pipes->child_ready[0]);
+ close(comm_pipes->child_ready[1]);
+ return -errno;
+ }
+
+ return 0;
+}
+
+static void close_comm_pipes(struct comm_pipes *comm_pipes)
+{
+ close(comm_pipes->child_ready[0]);
+ close(comm_pipes->child_ready[1]);
+ close(comm_pipes->parent_ready[0]);
+ close(comm_pipes->parent_ready[1]);
+}
+
+static int child_memcmp_fn(char *mem, size_t size,
+ struct comm_pipes *comm_pipes)
+{
+ char *old = malloc(size);
+ char buf;
+
+ /* Backup the original content. */
+ memcpy(old, mem, size);
+
+ /* Wait until the parent modified the page. */
+ write(comm_pipes->child_ready[1], "0", 1);
+ while (read(comm_pipes->parent_ready[0], &buf, 1) != 1)
+ ;
+
+ /* See if we still read the old values. */
+ return memcmp(old, mem, size);
+}
+
+static int child_vmsplice_memcmp_fn(char *mem, size_t size,
+ struct comm_pipes *comm_pipes)
+{
+ struct iovec iov = {
+ .iov_base = mem,
+ .iov_len = size,
+ };
+ ssize_t cur, total, transferred;
+ char *old, *new;
+ int fds[2];
+ char buf;
+
+ old = malloc(size);
+ new = malloc(size);
+
+ /* Backup the original content. */
+ memcpy(old, mem, size);
+
+ if (pipe(fds) < 0)
+ return -errno;
+
+ /* Trigger a read-only pin. */
+ transferred = vmsplice(fds[1], &iov, 1, 0);
+ if (transferred < 0)
+ return -errno;
+ if (transferred == 0)
+ return -EINVAL;
+
+ /* Unmap it from our page tables. */
+ if (munmap(mem, size) < 0)
+ return -errno;
+
+ /* Wait until the parent modified it. */
+ write(comm_pipes->child_ready[1], "0", 1);
+ while (read(comm_pipes->parent_ready[0], &buf, 1) != 1)
+ ;
+
+ /* See if we still read the old values via the pipe. */
+ for (total = 0; total < transferred; total += cur) {
+ cur = read(fds[0], new + total, transferred - total);
+ if (cur < 0)
+ return -errno;
+ }
+
+ return memcmp(old, new, transferred);
+}
+
+typedef int (*child_fn)(char *mem, size_t size, struct comm_pipes *comm_pipes);
+
+static void do_test_cow_in_parent(char *mem, size_t size, bool do_mprotect,
+ child_fn fn)
+{
+ struct comm_pipes comm_pipes;
+ char buf;
+ int ret;
+
+ ret = setup_comm_pipes(&comm_pipes);
+ if (ret) {
+ ksft_test_result_fail("pipe() failed\n");
+ return;
+ }
+
+ ret = fork();
+ if (ret < 0) {
+ ksft_test_result_fail("fork() failed\n");
+ goto close_comm_pipes;
+ } else if (!ret) {
+ exit(fn(mem, size, &comm_pipes));
+ }
+
+ while (read(comm_pipes.child_ready[0], &buf, 1) != 1)
+ ;
+
+ if (do_mprotect) {
+ /*
+ * mprotect() optimizations might try avoiding
+ * write-faults by directly mapping pages writable.
+ */
+ ret = mprotect(mem, size, PROT_READ);
+ ret |= mprotect(mem, size, PROT_READ|PROT_WRITE);
+ if (ret) {
+ ksft_test_result_fail("mprotect() failed\n");
+ write(comm_pipes.parent_ready[1], "0", 1);
+ wait(&ret);
+ goto close_comm_pipes;
+ }
+ }
+
+ /* Modify the page. */
+ memset(mem, 0xff, size);
+ write(comm_pipes.parent_ready[1], "0", 1);
+
+ wait(&ret);
+ if (WIFEXITED(ret))
+ ret = WEXITSTATUS(ret);
+ else
+ ret = -EINVAL;
+
+ ksft_test_result(!ret, "No leak from parent into child\n");
+close_comm_pipes:
+ close_comm_pipes(&comm_pipes);
+}
+
+static void test_cow_in_parent(char *mem, size_t size)
+{
+ do_test_cow_in_parent(mem, size, false, child_memcmp_fn);
+}
+
+static void test_cow_in_parent_mprotect(char *mem, size_t size)
+{
+ do_test_cow_in_parent(mem, size, true, child_memcmp_fn);
+}
+
+static void test_vmsplice_in_child(char *mem, size_t size)
+{
+ do_test_cow_in_parent(mem, size, false, child_vmsplice_memcmp_fn);
+}
+
+static void test_vmsplice_in_child_mprotect(char *mem, size_t size)
+{
+ do_test_cow_in_parent(mem, size, true, child_vmsplice_memcmp_fn);
+}
+
+static void do_test_vmsplice_in_parent(char *mem, size_t size,
+ bool before_fork)
+{
+ struct iovec iov = {
+ .iov_base = mem,
+ .iov_len = size,
+ };
+ ssize_t cur, total, transferred;
+ struct comm_pipes comm_pipes;
+ char *old, *new;
+ int ret, fds[2];
+ char buf;
+
+ old = malloc(size);
+ new = malloc(size);
+
+ memcpy(old, mem, size);
+
+ ret = setup_comm_pipes(&comm_pipes);
+ if (ret) {
+ ksft_test_result_fail("pipe() failed\n");
+ goto free;
+ }
+
+ if (pipe(fds) < 0) {
+ ksft_test_result_fail("pipe() failed\n");
+ goto close_comm_pipes;
+ }
+
+ if (before_fork) {
+ transferred = vmsplice(fds[1], &iov, 1, 0);
+ if (transferred <= 0) {
+ ksft_test_result_fail("vmsplice() failed\n");
+ goto close_pipe;
+ }
+ }
+
+ ret = fork();
+ if (ret < 0) {
+ ksft_test_result_fail("fork() failed\n");
+ goto close_pipe;
+ } else if (!ret) {
+ write(comm_pipes.child_ready[1], "0", 1);
+ while (read(comm_pipes.parent_ready[0], &buf, 1) != 1)
+ ;
+ /* Modify page content in the child. */
+ memset(mem, 0xff, size);
+ exit(0);
+ }
+
+ if (!before_fork) {
+ transferred = vmsplice(fds[1], &iov, 1, 0);
+ if (transferred <= 0) {
+ ksft_test_result_fail("vmsplice() failed\n");
+ wait(&ret);
+ goto close_pipe;
+ }
+ }
+
+ while (read(comm_pipes.child_ready[0], &buf, 1) != 1)
+ ;
+ if (munmap(mem, size) < 0) {
+ ksft_test_result_fail("munmap() failed\n");
+ goto close_pipe;
+ }
+ write(comm_pipes.parent_ready[1], "0", 1);
+
+ /* Wait until the child is done writing. */
+ wait(&ret);
+ if (!WIFEXITED(ret)) {
+ ksft_test_result_fail("wait() failed\n");
+ goto close_pipe;
+ }
+
+ /* See if we still read the old values. */
+ for (total = 0; total < transferred; total += cur) {
+ cur = read(fds[0], new + total, transferred - total);
+ if (cur < 0) {
+ ksft_test_result_fail("read() failed\n");
+ goto close_pipe;
+ }
+ }
+
+ ksft_test_result(!memcmp(old, new, transferred),
+ "No leak from child into parent\n");
+close_pipe:
+ close(fds[0]);
+ close(fds[1]);
+close_comm_pipes:
+ close_comm_pipes(&comm_pipes);
+free:
+ free(old);
+ free(new);
+}
+
+static void test_vmsplice_before_fork(char *mem, size_t size)
+{
+ do_test_vmsplice_in_parent(mem, size, true);
+}
+
+static void test_vmsplice_after_fork(char *mem, size_t size)
+{
+ do_test_vmsplice_in_parent(mem, size, false);
+}
+
+#ifdef LOCAL_CONFIG_HAVE_LIBURING
+static void do_test_iouring(char *mem, size_t size, bool use_fork)
+{
+ struct comm_pipes comm_pipes;
+ struct io_uring_cqe *cqe;
+ struct io_uring_sqe *sqe;
+ struct io_uring ring;
+ ssize_t cur, total;
+ struct iovec iov;
+ char *buf, *tmp;
+ int ret, fd;
+ FILE *file;
+
+ ret = setup_comm_pipes(&comm_pipes);
+ if (ret) {
+ ksft_test_result_fail("pipe() failed\n");
+ return;
+ }
+
+ file = tmpfile();
+ if (!file) {
+ ksft_test_result_fail("tmpfile() failed\n");
+ goto close_comm_pipes;
+ }
+ fd = fileno(file);
+ assert(fd);
+
+ tmp = malloc(size);
+ if (!tmp) {
+ ksft_test_result_fail("malloc() failed\n");
+ goto close_file;
+ }
+
+ /* Skip on errors, as we might just lack kernel support. */
+ ret = io_uring_queue_init(1, &ring, 0);
+ if (ret < 0) {
+ ksft_test_result_skip("io_uring_queue_init() failed\n");
+ goto free_tmp;
+ }
+
+ /*
+ * Register the range as a fixed buffer. This will FOLL_WRITE | FOLL_PIN
+ * | FOLL_LONGTERM the range.
+ *
+ * Skip on errors, as we might just lack kernel support or might not
+ * have sufficient MEMLOCK permissions.
+ */
+ iov.iov_base = mem;
+ iov.iov_len = size;
+ ret = io_uring_register_buffers(&ring, &iov, 1);
+ if (ret) {
+ ksft_test_result_skip("io_uring_register_buffers() failed\n");
+ goto queue_exit;
+ }
+
+ if (use_fork) {
+ /*
+ * fork() and keep the child alive until we're done. Note that
+ * we expect the pinned page to not get shared with the child.
+ */
+ ret = fork();
+ if (ret < 0) {
+ ksft_test_result_fail("fork() failed\n");
+ goto unregister_buffers;
+ } else if (!ret) {
+ write(comm_pipes.child_ready[1], "0", 1);
+ while (read(comm_pipes.parent_ready[0], &buf, 1) != 1)
+ ;
+ exit(0);
+ }
+
+ while (read(comm_pipes.child_ready[0], &buf, 1) != 1)
+ ;
+ } else {
+ /*
+ * Map the page R/O into the page table. Enable softdirty
+ * tracking to stop the page from getting mapped R/W immediately
+ * again by mprotect() optimizations. Note that we don't have an
+ * easy way to test if that worked (the pagemap does not export
+ * if the page is mapped R/O vs. R/W).
+ */
+ ret = mprotect(mem, size, PROT_READ);
+ clear_softdirty();
+ ret |= mprotect(mem, size, PROT_READ | PROT_WRITE);
+ if (ret) {
+ ksft_test_result_fail("mprotect() failed\n");
+ goto unregister_buffers;
+ }
+ }
+
+ /*
+ * Modify the page and write page content as observed by the fixed
+ * buffer pin to the file so we can verify it.
+ */
+ memset(mem, 0xff, size);
+ sqe = io_uring_get_sqe(&ring);
+ if (!sqe) {
+ ksft_test_result_fail("io_uring_get_sqe() failed\n");
+ goto quit_child;
+ }
+ io_uring_prep_write_fixed(sqe, fd, mem, size, 0, 0);
+
+ ret = io_uring_submit(&ring);
+ if (ret < 0) {
+ ksft_test_result_fail("io_uring_submit() failed\n");
+ goto quit_child;
+ }
+
+ ret = io_uring_wait_cqe(&ring, &cqe);
+ if (ret < 0) {
+ ksft_test_result_fail("io_uring_wait_cqe() failed\n");
+ goto quit_child;
+ }
+
+ if (cqe->res != size) {
+ ksft_test_result_fail("write_fixed failed\n");
+ goto quit_child;
+ }
+ io_uring_cqe_seen(&ring, cqe);
+
+ /* Read back the file content to the temporary buffer. */
+ total = 0;
+ while (total < size) {
+ cur = pread(fd, tmp + total, size - total, total);
+ if (cur < 0) {
+ ksft_test_result_fail("pread() failed\n");
+ goto quit_child;
+ }
+ total += cur;
+ }
+
+ /* Finally, check if we read what we expected. */
+ ksft_test_result(!memcmp(mem, tmp, size),
+ "Longterm R/W pin is reliable\n");
+
+quit_child:
+ if (use_fork) {
+ write(comm_pipes.parent_ready[1], "0", 1);
+ wait(&ret);
+ }
+unregister_buffers:
+ io_uring_unregister_buffers(&ring);
+queue_exit:
+ io_uring_queue_exit(&ring);
+free_tmp:
+ free(tmp);
+close_file:
+ fclose(file);
+close_comm_pipes:
+ close_comm_pipes(&comm_pipes);
+}
+
+static void test_iouring_ro(char *mem, size_t size)
+{
+ do_test_iouring(mem, size, false);
+}
+
+static void test_iouring_fork(char *mem, size_t size)
+{
+ do_test_iouring(mem, size, true);
+}
+
+#endif /* LOCAL_CONFIG_HAVE_LIBURING */
+
+enum ro_pin_test {
+ RO_PIN_TEST,
+ RO_PIN_TEST_SHARED,
+ RO_PIN_TEST_PREVIOUSLY_SHARED,
+ RO_PIN_TEST_RO_EXCLUSIVE,
+};
+
+static void do_test_ro_pin(char *mem, size_t size, enum ro_pin_test test,
+ bool fast)
+{
+ struct pin_longterm_test args;
+ struct comm_pipes comm_pipes;
+ char *tmp, buf;
+ __u64 tmp_val;
+ int ret;
+
+ if (gup_fd < 0) {
+ ksft_test_result_skip("gup_test not available\n");
+ return;
+ }
+
+ tmp = malloc(size);
+ if (!tmp) {
+ ksft_test_result_fail("malloc() failed\n");
+ return;
+ }
+
+ ret = setup_comm_pipes(&comm_pipes);
+ if (ret) {
+ ksft_test_result_fail("pipe() failed\n");
+ goto free_tmp;
+ }
+
+ switch (test) {
+ case RO_PIN_TEST:
+ break;
+ case RO_PIN_TEST_SHARED:
+ case RO_PIN_TEST_PREVIOUSLY_SHARED:
+ /*
+ * Share the pages with our child. As the pages are not pinned,
+ * this should just work.
+ */
+ ret = fork();
+ if (ret < 0) {
+ ksft_test_result_fail("fork() failed\n");
+ goto close_comm_pipes;
+ } else if (!ret) {
+ write(comm_pipes.child_ready[1], "0", 1);
+ while (read(comm_pipes.parent_ready[0], &buf, 1) != 1)
+ ;
+ exit(0);
+ }
+
+ /* Wait until our child is ready. */
+ while (read(comm_pipes.child_ready[0], &buf, 1) != 1)
+ ;
+
+ if (test == RO_PIN_TEST_PREVIOUSLY_SHARED) {
+ /*
+ * Tell the child to quit now and wait until it quit.
+ * The pages should now be mapped R/O into our page
+ * tables, but they are no longer shared.
+ */
+ write(comm_pipes.parent_ready[1], "0", 1);
+ wait(&ret);
+ if (!WIFEXITED(ret))
+ ksft_print_msg("[INFO] wait() failed\n");
+ }
+ break;
+ case RO_PIN_TEST_RO_EXCLUSIVE:
+ /*
+ * Map the page R/O into the page table. Enable softdirty
+ * tracking to stop the page from getting mapped R/W immediately
+ * again by mprotect() optimizations. Note that we don't have an
+ * easy way to test if that worked (the pagemap does not export
+ * if the page is mapped R/O vs. R/W).
+ */
+ ret = mprotect(mem, size, PROT_READ);
+ clear_softdirty();
+ ret |= mprotect(mem, size, PROT_READ | PROT_WRITE);
+ if (ret) {
+ ksft_test_result_fail("mprotect() failed\n");
+ goto close_comm_pipes;
+ }
+ break;
+ default:
+ assert(false);
+ }
+
+ /* Take a R/O pin. This should trigger unsharing. */
+ args.addr = (__u64)(uintptr_t)mem;
+ args.size = size;
+ args.flags = fast ? PIN_LONGTERM_TEST_FLAG_USE_FAST : 0;
+ ret = ioctl(gup_fd, PIN_LONGTERM_TEST_START, &args);
+ if (ret) {
+ if (errno == EINVAL)
+ ksft_test_result_skip("PIN_LONGTERM_TEST_START failed\n");
+ else
+ ksft_test_result_fail("PIN_LONGTERM_TEST_START failed\n");
+ goto wait;
+ }
+
+ /* Modify the page. */
+ memset(mem, 0xff, size);
+
+ /*
+ * Read back the content via the pin to the temporary buffer and
+ * test if we observed the modification.
+ */
+ tmp_val = (__u64)(uintptr_t)tmp;
+ ret = ioctl(gup_fd, PIN_LONGTERM_TEST_READ, &tmp_val);
+ if (ret)
+ ksft_test_result_fail("PIN_LONGTERM_TEST_READ failed\n");
+ else
+ ksft_test_result(!memcmp(mem, tmp, size),
+ "Longterm R/O pin is reliable\n");
+
+ ret = ioctl(gup_fd, PIN_LONGTERM_TEST_STOP);
+ if (ret)
+ ksft_print_msg("[INFO] PIN_LONGTERM_TEST_STOP failed\n");
+wait:
+ switch (test) {
+ case RO_PIN_TEST_SHARED:
+ write(comm_pipes.parent_ready[1], "0", 1);
+ wait(&ret);
+ if (!WIFEXITED(ret))
+ ksft_print_msg("[INFO] wait() failed\n");
+ break;
+ default:
+ break;
+ }
+close_comm_pipes:
+ close_comm_pipes(&comm_pipes);
+free_tmp:
+ free(tmp);
+}
+
+static void test_ro_pin_on_shared(char *mem, size_t size)
+{
+ do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, false);
+}
+
+static void test_ro_fast_pin_on_shared(char *mem, size_t size)
+{
+ do_test_ro_pin(mem, size, RO_PIN_TEST_SHARED, true);
+}
+
+static void test_ro_pin_on_ro_previously_shared(char *mem, size_t size)
+{
+ do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, false);
+}
+
+static void test_ro_fast_pin_on_ro_previously_shared(char *mem, size_t size)
+{
+ do_test_ro_pin(mem, size, RO_PIN_TEST_PREVIOUSLY_SHARED, true);
+}
+
+static void test_ro_pin_on_ro_exclusive(char *mem, size_t size)
+{
+ do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, false);
+}
+
+static void test_ro_fast_pin_on_ro_exclusive(char *mem, size_t size)
+{
+ do_test_ro_pin(mem, size, RO_PIN_TEST_RO_EXCLUSIVE, true);
+}
+
+typedef void (*test_fn)(char *mem, size_t size);
+
+static void do_run_with_base_page(test_fn fn, bool swapout)
+{
+ char *mem;
+ int ret;
+
+ mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ return;
+ }
+
+ ret = madvise(mem, pagesize, MADV_NOHUGEPAGE);
+ /* Ignore if not around on a kernel. */
+ if (ret && errno != EINVAL) {
+ ksft_test_result_fail("MADV_NOHUGEPAGE failed\n");
+ goto munmap;
+ }
+
+ /* Populate a base page. */
+ memset(mem, 0, pagesize);
+
+ if (swapout) {
+ madvise(mem, pagesize, MADV_PAGEOUT);
+ if (!pagemap_is_swapped(pagemap_fd, mem)) {
+ ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n");
+ goto munmap;
+ }
+ }
+
+ fn(mem, pagesize);
+munmap:
+ munmap(mem, pagesize);
+}
+
+static void run_with_base_page(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with base page\n", desc);
+ do_run_with_base_page(fn, false);
+}
+
+static void run_with_base_page_swap(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with swapped out base page\n", desc);
+ do_run_with_base_page(fn, true);
+}
+
+enum thp_run {
+ THP_RUN_PMD,
+ THP_RUN_PMD_SWAPOUT,
+ THP_RUN_PTE,
+ THP_RUN_PTE_SWAPOUT,
+ THP_RUN_SINGLE_PTE,
+ THP_RUN_SINGLE_PTE_SWAPOUT,
+ THP_RUN_PARTIAL_MREMAP,
+ THP_RUN_PARTIAL_SHARED,
+};
+
+static void do_run_with_thp(test_fn fn, enum thp_run thp_run)
+{
+ char *mem, *mmap_mem, *tmp, *mremap_mem = MAP_FAILED;
+ size_t size, mmap_size, mremap_size;
+ int ret;
+
+ /* For alignment purposes, we need twice the thp size. */
+ mmap_size = 2 * thpsize;
+ mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (mmap_mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ return;
+ }
+
+ /* We need a THP-aligned memory area. */
+ mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1));
+
+ ret = madvise(mem, thpsize, MADV_HUGEPAGE);
+ if (ret) {
+ ksft_test_result_fail("MADV_HUGEPAGE failed\n");
+ goto munmap;
+ }
+
+ /*
+ * Try to populate a THP. Touch the first sub-page and test if we get
+ * another sub-page populated automatically.
+ */
+ mem[0] = 0;
+ if (!pagemap_is_populated(pagemap_fd, mem + pagesize)) {
+ ksft_test_result_skip("Did not get a THP populated\n");
+ goto munmap;
+ }
+ memset(mem, 0, thpsize);
+
+ size = thpsize;
+ switch (thp_run) {
+ case THP_RUN_PMD:
+ case THP_RUN_PMD_SWAPOUT:
+ break;
+ case THP_RUN_PTE:
+ case THP_RUN_PTE_SWAPOUT:
+ /*
+ * Trigger PTE-mapping the THP by temporarily mapping a single
+ * subpage R/O.
+ */
+ ret = mprotect(mem + pagesize, pagesize, PROT_READ);
+ if (ret) {
+ ksft_test_result_fail("mprotect() failed\n");
+ goto munmap;
+ }
+ ret = mprotect(mem + pagesize, pagesize, PROT_READ | PROT_WRITE);
+ if (ret) {
+ ksft_test_result_fail("mprotect() failed\n");
+ goto munmap;
+ }
+ break;
+ case THP_RUN_SINGLE_PTE:
+ case THP_RUN_SINGLE_PTE_SWAPOUT:
+ /*
+ * Discard all but a single subpage of that PTE-mapped THP. What
+ * remains is a single PTE mapping a single subpage.
+ */
+ ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTNEED);
+ if (ret) {
+ ksft_test_result_fail("MADV_DONTNEED failed\n");
+ goto munmap;
+ }
+ size = pagesize;
+ break;
+ case THP_RUN_PARTIAL_MREMAP:
+ /*
+ * Remap half of the THP. We need some new memory location
+ * for that.
+ */
+ mremap_size = thpsize / 2;
+ mremap_mem = mmap(NULL, mremap_size, PROT_NONE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ goto munmap;
+ }
+ tmp = mremap(mem + mremap_size, mremap_size, mremap_size,
+ MREMAP_MAYMOVE | MREMAP_FIXED, mremap_mem);
+ if (tmp != mremap_mem) {
+ ksft_test_result_fail("mremap() failed\n");
+ goto munmap;
+ }
+ size = mremap_size;
+ break;
+ case THP_RUN_PARTIAL_SHARED:
+ /*
+ * Share the first page of the THP with a child and quit the
+ * child. This will result in some parts of the THP never
+ * have been shared.
+ */
+ ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DONTFORK);
+ if (ret) {
+ ksft_test_result_fail("MADV_DONTFORK failed\n");
+ goto munmap;
+ }
+ ret = fork();
+ if (ret < 0) {
+ ksft_test_result_fail("fork() failed\n");
+ goto munmap;
+ } else if (!ret) {
+ exit(0);
+ }
+ wait(&ret);
+ /* Allow for sharing all pages again. */
+ ret = madvise(mem + pagesize, thpsize - pagesize, MADV_DOFORK);
+ if (ret) {
+ ksft_test_result_fail("MADV_DOFORK failed\n");
+ goto munmap;
+ }
+ break;
+ default:
+ assert(false);
+ }
+
+ switch (thp_run) {
+ case THP_RUN_PMD_SWAPOUT:
+ case THP_RUN_PTE_SWAPOUT:
+ case THP_RUN_SINGLE_PTE_SWAPOUT:
+ madvise(mem, size, MADV_PAGEOUT);
+ if (!range_is_swapped(mem, size)) {
+ ksft_test_result_skip("MADV_PAGEOUT did not work, is swap enabled?\n");
+ goto munmap;
+ }
+ break;
+ default:
+ break;
+ }
+
+ fn(mem, size);
+munmap:
+ munmap(mmap_mem, mmap_size);
+ if (mremap_mem != MAP_FAILED)
+ munmap(mremap_mem, mremap_size);
+}
+
+static void run_with_thp(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with THP\n", desc);
+ do_run_with_thp(fn, THP_RUN_PMD);
+}
+
+static void run_with_thp_swap(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with swapped-out THP\n", desc);
+ do_run_with_thp(fn, THP_RUN_PMD_SWAPOUT);
+}
+
+static void run_with_pte_mapped_thp(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with PTE-mapped THP\n", desc);
+ do_run_with_thp(fn, THP_RUN_PTE);
+}
+
+static void run_with_pte_mapped_thp_swap(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with swapped-out, PTE-mapped THP\n", desc);
+ do_run_with_thp(fn, THP_RUN_PTE_SWAPOUT);
+}
+
+static void run_with_single_pte_of_thp(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with single PTE of THP\n", desc);
+ do_run_with_thp(fn, THP_RUN_SINGLE_PTE);
+}
+
+static void run_with_single_pte_of_thp_swap(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with single PTE of swapped-out THP\n", desc);
+ do_run_with_thp(fn, THP_RUN_SINGLE_PTE_SWAPOUT);
+}
+
+static void run_with_partial_mremap_thp(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with partially mremap()'ed THP\n", desc);
+ do_run_with_thp(fn, THP_RUN_PARTIAL_MREMAP);
+}
+
+static void run_with_partial_shared_thp(test_fn fn, const char *desc)
+{
+ ksft_print_msg("[RUN] %s ... with partially shared THP\n", desc);
+ do_run_with_thp(fn, THP_RUN_PARTIAL_SHARED);
+}
+
+static void run_with_hugetlb(test_fn fn, const char *desc, size_t hugetlbsize)
+{
+ int flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB;
+ char *mem, *dummy;
+
+ ksft_print_msg("[RUN] %s ... with hugetlb (%zu kB)\n", desc,
+ hugetlbsize / 1024);
+
+ flags |= __builtin_ctzll(hugetlbsize) << MAP_HUGE_SHIFT;
+
+ mem = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_skip("need more free huge pages\n");
+ return;
+ }
+
+ /* Populate an huge page. */
+ memset(mem, 0, hugetlbsize);
+
+ /*
+ * We need a total of two hugetlb pages to handle COW/unsharing
+ * properly, otherwise we might get zapped by a SIGBUS.
+ */
+ dummy = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, flags, -1, 0);
+ if (dummy == MAP_FAILED) {
+ ksft_test_result_skip("need more free huge pages\n");
+ goto munmap;
+ }
+ munmap(dummy, hugetlbsize);
+
+ fn(mem, hugetlbsize);
+munmap:
+ munmap(mem, hugetlbsize);
+}
+
+struct test_case {
+ const char *desc;
+ test_fn fn;
+};
+
+/*
+ * Test cases that are specific to anonymous pages: pages in private mappings
+ * that may get shared via COW during fork().
+ */
+static const struct test_case anon_test_cases[] = {
+ /*
+ * Basic COW tests for fork() without any GUP. If we miss to break COW,
+ * either the child can observe modifications by the parent or the
+ * other way around.
+ */
+ {
+ "Basic COW after fork()",
+ test_cow_in_parent,
+ },
+ /*
+ * Basic test, but do an additional mprotect(PROT_READ)+
+ * mprotect(PROT_READ|PROT_WRITE) in the parent before write access.
+ */
+ {
+ "Basic COW after fork() with mprotect() optimization",
+ test_cow_in_parent_mprotect,
+ },
+ /*
+ * vmsplice() [R/O GUP] + unmap in the child; modify in the parent. If
+ * we miss to break COW, the child observes modifications by the parent.
+ * This is CVE-2020-29374 reported by Jann Horn.
+ */
+ {
+ "vmsplice() + unmap in child",
+ test_vmsplice_in_child
+ },
+ /*
+ * vmsplice() test, but do an additional mprotect(PROT_READ)+
+ * mprotect(PROT_READ|PROT_WRITE) in the parent before write access.
+ */
+ {
+ "vmsplice() + unmap in child with mprotect() optimization",
+ test_vmsplice_in_child_mprotect
+ },
+ /*
+ * vmsplice() [R/O GUP] in parent before fork(), unmap in parent after
+ * fork(); modify in the child. If we miss to break COW, the parent
+ * observes modifications by the child.
+ */
+ {
+ "vmsplice() before fork(), unmap in parent after fork()",
+ test_vmsplice_before_fork,
+ },
+ /*
+ * vmsplice() [R/O GUP] + unmap in parent after fork(); modify in the
+ * child. If we miss to break COW, the parent observes modifications by
+ * the child.
+ */
+ {
+ "vmsplice() + unmap in parent after fork()",
+ test_vmsplice_after_fork,
+ },
+#ifdef LOCAL_CONFIG_HAVE_LIBURING
+ /*
+ * Take a R/W longterm pin and then map the page R/O into the page
+ * table to trigger a write fault on next access. When modifying the
+ * page, the page content must be visible via the pin.
+ */
+ {
+ "R/O-mapping a page registered as iouring fixed buffer",
+ test_iouring_ro,
+ },
+ /*
+ * Take a R/W longterm pin and then fork() a child. When modifying the
+ * page, the page content must be visible via the pin. We expect the
+ * pinned page to not get shared with the child.
+ */
+ {
+ "fork() with an iouring fixed buffer",
+ test_iouring_fork,
+ },
+
+#endif /* LOCAL_CONFIG_HAVE_LIBURING */
+ /*
+ * Take a R/O longterm pin on a R/O-mapped shared anonymous page.
+ * When modifying the page via the page table, the page content change
+ * must be visible via the pin.
+ */
+ {
+ "R/O GUP pin on R/O-mapped shared page",
+ test_ro_pin_on_shared,
+ },
+ /* Same as above, but using GUP-fast. */
+ {
+ "R/O GUP-fast pin on R/O-mapped shared page",
+ test_ro_fast_pin_on_shared,
+ },
+ /*
+ * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page that
+ * was previously shared. When modifying the page via the page table,
+ * the page content change must be visible via the pin.
+ */
+ {
+ "R/O GUP pin on R/O-mapped previously-shared page",
+ test_ro_pin_on_ro_previously_shared,
+ },
+ /* Same as above, but using GUP-fast. */
+ {
+ "R/O GUP-fast pin on R/O-mapped previously-shared page",
+ test_ro_fast_pin_on_ro_previously_shared,
+ },
+ /*
+ * Take a R/O longterm pin on a R/O-mapped exclusive anonymous page.
+ * When modifying the page via the page table, the page content change
+ * must be visible via the pin.
+ */
+ {
+ "R/O GUP pin on R/O-mapped exclusive page",
+ test_ro_pin_on_ro_exclusive,
+ },
+ /* Same as above, but using GUP-fast. */
+ {
+ "R/O GUP-fast pin on R/O-mapped exclusive page",
+ test_ro_fast_pin_on_ro_exclusive,
+ },
+};
+
+static void run_anon_test_case(struct test_case const *test_case)
+{
+ int i;
+
+ run_with_base_page(test_case->fn, test_case->desc);
+ run_with_base_page_swap(test_case->fn, test_case->desc);
+ if (thpsize) {
+ run_with_thp(test_case->fn, test_case->desc);
+ run_with_thp_swap(test_case->fn, test_case->desc);
+ run_with_pte_mapped_thp(test_case->fn, test_case->desc);
+ run_with_pte_mapped_thp_swap(test_case->fn, test_case->desc);
+ run_with_single_pte_of_thp(test_case->fn, test_case->desc);
+ run_with_single_pte_of_thp_swap(test_case->fn, test_case->desc);
+ run_with_partial_mremap_thp(test_case->fn, test_case->desc);
+ run_with_partial_shared_thp(test_case->fn, test_case->desc);
+ }
+ for (i = 0; i < nr_hugetlbsizes; i++)
+ run_with_hugetlb(test_case->fn, test_case->desc,
+ hugetlbsizes[i]);
+}
+
+static void run_anon_test_cases(void)
+{
+ int i;
+
+ ksft_print_msg("[INFO] Anonymous memory tests in private mappings\n");
+
+ for (i = 0; i < ARRAY_SIZE(anon_test_cases); i++)
+ run_anon_test_case(&anon_test_cases[i]);
+}
+
+static int tests_per_anon_test_case(void)
+{
+ int tests = 2 + nr_hugetlbsizes;
+
+ if (thpsize)
+ tests += 8;
+ return tests;
+}
+
+enum anon_thp_collapse_test {
+ ANON_THP_COLLAPSE_UNSHARED,
+ ANON_THP_COLLAPSE_FULLY_SHARED,
+ ANON_THP_COLLAPSE_LOWER_SHARED,
+ ANON_THP_COLLAPSE_UPPER_SHARED,
+};
+
+static void do_test_anon_thp_collapse(char *mem, size_t size,
+ enum anon_thp_collapse_test test)
+{
+ struct comm_pipes comm_pipes;
+ char buf;
+ int ret;
+
+ ret = setup_comm_pipes(&comm_pipes);
+ if (ret) {
+ ksft_test_result_fail("pipe() failed\n");
+ return;
+ }
+
+ /*
+ * Trigger PTE-mapping the THP by temporarily mapping a single subpage
+ * R/O, such that we can try collapsing it later.
+ */
+ ret = mprotect(mem + pagesize, pagesize, PROT_READ);
+ if (ret) {
+ ksft_test_result_fail("mprotect() failed\n");
+ goto close_comm_pipes;
+ }
+ ret = mprotect(mem + pagesize, pagesize, PROT_READ | PROT_WRITE);
+ if (ret) {
+ ksft_test_result_fail("mprotect() failed\n");
+ goto close_comm_pipes;
+ }
+
+ switch (test) {
+ case ANON_THP_COLLAPSE_UNSHARED:
+ /* Collapse before actually COW-sharing the page. */
+ ret = madvise(mem, size, MADV_COLLAPSE);
+ if (ret) {
+ ksft_test_result_skip("MADV_COLLAPSE failed: %s\n",
+ strerror(errno));
+ goto close_comm_pipes;
+ }
+ break;
+ case ANON_THP_COLLAPSE_FULLY_SHARED:
+ /* COW-share the full PTE-mapped THP. */
+ break;
+ case ANON_THP_COLLAPSE_LOWER_SHARED:
+ /* Don't COW-share the upper part of the THP. */
+ ret = madvise(mem + size / 2, size / 2, MADV_DONTFORK);
+ if (ret) {
+ ksft_test_result_fail("MADV_DONTFORK failed\n");
+ goto close_comm_pipes;
+ }
+ break;
+ case ANON_THP_COLLAPSE_UPPER_SHARED:
+ /* Don't COW-share the lower part of the THP. */
+ ret = madvise(mem, size / 2, MADV_DONTFORK);
+ if (ret) {
+ ksft_test_result_fail("MADV_DONTFORK failed\n");
+ goto close_comm_pipes;
+ }
+ break;
+ default:
+ assert(false);
+ }
+
+ ret = fork();
+ if (ret < 0) {
+ ksft_test_result_fail("fork() failed\n");
+ goto close_comm_pipes;
+ } else if (!ret) {
+ switch (test) {
+ case ANON_THP_COLLAPSE_UNSHARED:
+ case ANON_THP_COLLAPSE_FULLY_SHARED:
+ exit(child_memcmp_fn(mem, size, &comm_pipes));
+ break;
+ case ANON_THP_COLLAPSE_LOWER_SHARED:
+ exit(child_memcmp_fn(mem, size / 2, &comm_pipes));
+ break;
+ case ANON_THP_COLLAPSE_UPPER_SHARED:
+ exit(child_memcmp_fn(mem + size / 2, size / 2,
+ &comm_pipes));
+ break;
+ default:
+ assert(false);
+ }
+ }
+
+ while (read(comm_pipes.child_ready[0], &buf, 1) != 1)
+ ;
+
+ switch (test) {
+ case ANON_THP_COLLAPSE_UNSHARED:
+ break;
+ case ANON_THP_COLLAPSE_UPPER_SHARED:
+ case ANON_THP_COLLAPSE_LOWER_SHARED:
+ /*
+ * Revert MADV_DONTFORK such that we merge the VMAs and are
+ * able to actually collapse.
+ */
+ ret = madvise(mem, size, MADV_DOFORK);
+ if (ret) {
+ ksft_test_result_fail("MADV_DOFORK failed\n");
+ write(comm_pipes.parent_ready[1], "0", 1);
+ wait(&ret);
+ goto close_comm_pipes;
+ }
+ /* FALLTHROUGH */
+ case ANON_THP_COLLAPSE_FULLY_SHARED:
+ /* Collapse before anyone modified the COW-shared page. */
+ ret = madvise(mem, size, MADV_COLLAPSE);
+ if (ret) {
+ ksft_test_result_skip("MADV_COLLAPSE failed: %s\n",
+ strerror(errno));
+ write(comm_pipes.parent_ready[1], "0", 1);
+ wait(&ret);
+ goto close_comm_pipes;
+ }
+ break;
+ default:
+ assert(false);
+ }
+
+ /* Modify the page. */
+ memset(mem, 0xff, size);
+ write(comm_pipes.parent_ready[1], "0", 1);
+
+ wait(&ret);
+ if (WIFEXITED(ret))
+ ret = WEXITSTATUS(ret);
+ else
+ ret = -EINVAL;
+
+ ksft_test_result(!ret, "No leak from parent into child\n");
+close_comm_pipes:
+ close_comm_pipes(&comm_pipes);
+}
+
+static void test_anon_thp_collapse_unshared(char *mem, size_t size)
+{
+ do_test_anon_thp_collapse(mem, size, ANON_THP_COLLAPSE_UNSHARED);
+}
+
+static void test_anon_thp_collapse_fully_shared(char *mem, size_t size)
+{
+ do_test_anon_thp_collapse(mem, size, ANON_THP_COLLAPSE_FULLY_SHARED);
+}
+
+static void test_anon_thp_collapse_lower_shared(char *mem, size_t size)
+{
+ do_test_anon_thp_collapse(mem, size, ANON_THP_COLLAPSE_LOWER_SHARED);
+}
+
+static void test_anon_thp_collapse_upper_shared(char *mem, size_t size)
+{
+ do_test_anon_thp_collapse(mem, size, ANON_THP_COLLAPSE_UPPER_SHARED);
+}
+
+/*
+ * Test cases that are specific to anonymous THP: pages in private mappings
+ * that may get shared via COW during fork().
+ */
+static const struct test_case anon_thp_test_cases[] = {
+ /*
+ * Basic COW test for fork() without any GUP when collapsing a THP
+ * before fork().
+ *
+ * Re-mapping a PTE-mapped anon THP using a single PMD ("in-place
+ * collapse") might easily get COW handling wrong when not collapsing
+ * exclusivity information properly.
+ */
+ {
+ "Basic COW after fork() when collapsing before fork()",
+ test_anon_thp_collapse_unshared,
+ },
+ /* Basic COW test, but collapse after COW-sharing a full THP. */
+ {
+ "Basic COW after fork() when collapsing after fork() (fully shared)",
+ test_anon_thp_collapse_fully_shared,
+ },
+ /*
+ * Basic COW test, but collapse after COW-sharing the lower half of a
+ * THP.
+ */
+ {
+ "Basic COW after fork() when collapsing after fork() (lower shared)",
+ test_anon_thp_collapse_lower_shared,
+ },
+ /*
+ * Basic COW test, but collapse after COW-sharing the upper half of a
+ * THP.
+ */
+ {
+ "Basic COW after fork() when collapsing after fork() (upper shared)",
+ test_anon_thp_collapse_upper_shared,
+ },
+};
+
+static void run_anon_thp_test_cases(void)
+{
+ int i;
+
+ if (!thpsize)
+ return;
+
+ ksft_print_msg("[INFO] Anonymous THP tests\n");
+
+ for (i = 0; i < ARRAY_SIZE(anon_thp_test_cases); i++) {
+ struct test_case const *test_case = &anon_thp_test_cases[i];
+
+ ksft_print_msg("[RUN] %s\n", test_case->desc);
+ do_run_with_thp(test_case->fn, THP_RUN_PMD);
+ }
+}
+
+static int tests_per_anon_thp_test_case(void)
+{
+ return thpsize ? 1 : 0;
+}
+
+typedef void (*non_anon_test_fn)(char *mem, const char *smem, size_t size);
+
+static void test_cow(char *mem, const char *smem, size_t size)
+{
+ char *old = malloc(size);
+
+ /* Backup the original content. */
+ memcpy(old, smem, size);
+
+ /* Modify the page. */
+ memset(mem, 0xff, size);
+
+ /* See if we still read the old values via the other mapping. */
+ ksft_test_result(!memcmp(smem, old, size),
+ "Other mapping not modified\n");
+ free(old);
+}
+
+static void test_ro_pin(char *mem, const char *smem, size_t size)
+{
+ do_test_ro_pin(mem, size, RO_PIN_TEST, false);
+}
+
+static void test_ro_fast_pin(char *mem, const char *smem, size_t size)
+{
+ do_test_ro_pin(mem, size, RO_PIN_TEST, true);
+}
+
+static void run_with_zeropage(non_anon_test_fn fn, const char *desc)
+{
+ char *mem, *smem, tmp;
+
+ ksft_print_msg("[RUN] %s ... with shared zeropage\n", desc);
+
+ mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON, -1, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ return;
+ }
+
+ smem = mmap(NULL, pagesize, PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ goto munmap;
+ }
+
+ /* Read from the page to populate the shared zeropage. */
+ tmp = *mem + *smem;
+ asm volatile("" : "+r" (tmp));
+
+ fn(mem, smem, pagesize);
+munmap:
+ munmap(mem, pagesize);
+ if (smem != MAP_FAILED)
+ munmap(smem, pagesize);
+}
+
+static void run_with_huge_zeropage(non_anon_test_fn fn, const char *desc)
+{
+ char *mem, *smem, *mmap_mem, *mmap_smem, tmp;
+ size_t mmap_size;
+ int ret;
+
+ ksft_print_msg("[RUN] %s ... with huge zeropage\n", desc);
+
+ if (!has_huge_zeropage) {
+ ksft_test_result_skip("Huge zeropage not enabled\n");
+ return;
+ }
+
+ /* For alignment purposes, we need twice the thp size. */
+ mmap_size = 2 * thpsize;
+ mmap_mem = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (mmap_mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ return;
+ }
+ mmap_smem = mmap(NULL, mmap_size, PROT_READ,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (mmap_smem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ goto munmap;
+ }
+
+ /* We need a THP-aligned memory area. */
+ mem = (char *)(((uintptr_t)mmap_mem + thpsize) & ~(thpsize - 1));
+ smem = (char *)(((uintptr_t)mmap_smem + thpsize) & ~(thpsize - 1));
+
+ ret = madvise(mem, thpsize, MADV_HUGEPAGE);
+ ret |= madvise(smem, thpsize, MADV_HUGEPAGE);
+ if (ret) {
+ ksft_test_result_fail("MADV_HUGEPAGE failed\n");
+ goto munmap;
+ }
+
+ /*
+ * Read from the memory to populate the huge shared zeropage. Read from
+ * the first sub-page and test if we get another sub-page populated
+ * automatically.
+ */
+ tmp = *mem + *smem;
+ asm volatile("" : "+r" (tmp));
+ if (!pagemap_is_populated(pagemap_fd, mem + pagesize) ||
+ !pagemap_is_populated(pagemap_fd, smem + pagesize)) {
+ ksft_test_result_skip("Did not get THPs populated\n");
+ goto munmap;
+ }
+
+ fn(mem, smem, thpsize);
+munmap:
+ munmap(mmap_mem, mmap_size);
+ if (mmap_smem != MAP_FAILED)
+ munmap(mmap_smem, mmap_size);
+}
+
+static void run_with_memfd(non_anon_test_fn fn, const char *desc)
+{
+ char *mem, *smem, tmp;
+ int fd;
+
+ ksft_print_msg("[RUN] %s ... with memfd\n", desc);
+
+ fd = memfd_create("test", 0);
+ if (fd < 0) {
+ ksft_test_result_fail("memfd_create() failed\n");
+ return;
+ }
+
+ /* File consists of a single page filled with zeroes. */
+ if (fallocate(fd, 0, 0, pagesize)) {
+ ksft_test_result_fail("fallocate() failed\n");
+ goto close;
+ }
+
+ /* Create a private mapping of the memfd. */
+ mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ goto close;
+ }
+ smem = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ goto munmap;
+ }
+
+ /* Fault the page in. */
+ tmp = *mem + *smem;
+ asm volatile("" : "+r" (tmp));
+
+ fn(mem, smem, pagesize);
+munmap:
+ munmap(mem, pagesize);
+ if (smem != MAP_FAILED)
+ munmap(smem, pagesize);
+close:
+ close(fd);
+}
+
+static void run_with_tmpfile(non_anon_test_fn fn, const char *desc)
+{
+ char *mem, *smem, tmp;
+ FILE *file;
+ int fd;
+
+ ksft_print_msg("[RUN] %s ... with tmpfile\n", desc);
+
+ file = tmpfile();
+ if (!file) {
+ ksft_test_result_fail("tmpfile() failed\n");
+ return;
+ }
+
+ fd = fileno(file);
+ if (fd < 0) {
+ ksft_test_result_skip("fileno() failed\n");
+ return;
+ }
+
+ /* File consists of a single page filled with zeroes. */
+ if (fallocate(fd, 0, 0, pagesize)) {
+ ksft_test_result_fail("fallocate() failed\n");
+ goto close;
+ }
+
+ /* Create a private mapping of the memfd. */
+ mem = mmap(NULL, pagesize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ goto close;
+ }
+ smem = mmap(NULL, pagesize, PROT_READ, MAP_SHARED, fd, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ goto munmap;
+ }
+
+ /* Fault the page in. */
+ tmp = *mem + *smem;
+ asm volatile("" : "+r" (tmp));
+
+ fn(mem, smem, pagesize);
+munmap:
+ munmap(mem, pagesize);
+ if (smem != MAP_FAILED)
+ munmap(smem, pagesize);
+close:
+ fclose(file);
+}
+
+static void run_with_memfd_hugetlb(non_anon_test_fn fn, const char *desc,
+ size_t hugetlbsize)
+{
+ int flags = MFD_HUGETLB;
+ char *mem, *smem, tmp;
+ int fd;
+
+ ksft_print_msg("[RUN] %s ... with memfd hugetlb (%zu kB)\n", desc,
+ hugetlbsize / 1024);
+
+ flags |= __builtin_ctzll(hugetlbsize) << MFD_HUGE_SHIFT;
+
+ fd = memfd_create("test", flags);
+ if (fd < 0) {
+ ksft_test_result_skip("memfd_create() failed\n");
+ return;
+ }
+
+ /* File consists of a single page filled with zeroes. */
+ if (fallocate(fd, 0, 0, hugetlbsize)) {
+ ksft_test_result_skip("need more free huge pages\n");
+ goto close;
+ }
+
+ /* Create a private mapping of the memfd. */
+ mem = mmap(NULL, hugetlbsize, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd,
+ 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_skip("need more free huge pages\n");
+ goto close;
+ }
+ smem = mmap(NULL, hugetlbsize, PROT_READ, MAP_SHARED, fd, 0);
+ if (mem == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ goto munmap;
+ }
+
+ /* Fault the page in. */
+ tmp = *mem + *smem;
+ asm volatile("" : "+r" (tmp));
+
+ fn(mem, smem, hugetlbsize);
+munmap:
+ munmap(mem, hugetlbsize);
+ if (mem != MAP_FAILED)
+ munmap(smem, hugetlbsize);
+close:
+ close(fd);
+}
+
+struct non_anon_test_case {
+ const char *desc;
+ non_anon_test_fn fn;
+};
+
+/*
+ * Test cases that target any pages in private mappings that are not anonymous:
+ * pages that may get shared via COW ndependent of fork(). This includes
+ * the shared zeropage(s), pagecache pages, ...
+ */
+static const struct non_anon_test_case non_anon_test_cases[] = {
+ /*
+ * Basic COW test without any GUP. If we miss to break COW, changes are
+ * visible via other private/shared mappings.
+ */
+ {
+ "Basic COW",
+ test_cow,
+ },
+ /*
+ * Take a R/O longterm pin. When modifying the page via the page table,
+ * the page content change must be visible via the pin.
+ */
+ {
+ "R/O longterm GUP pin",
+ test_ro_pin,
+ },
+ /* Same as above, but using GUP-fast. */
+ {
+ "R/O longterm GUP-fast pin",
+ test_ro_fast_pin,
+ },
+};
+
+static void run_non_anon_test_case(struct non_anon_test_case const *test_case)
+{
+ int i;
+
+ run_with_zeropage(test_case->fn, test_case->desc);
+ run_with_memfd(test_case->fn, test_case->desc);
+ run_with_tmpfile(test_case->fn, test_case->desc);
+ if (thpsize)
+ run_with_huge_zeropage(test_case->fn, test_case->desc);
+ for (i = 0; i < nr_hugetlbsizes; i++)
+ run_with_memfd_hugetlb(test_case->fn, test_case->desc,
+ hugetlbsizes[i]);
+}
+
+static void run_non_anon_test_cases(void)
+{
+ int i;
+
+ ksft_print_msg("[RUN] Non-anonymous memory tests in private mappings\n");
+
+ for (i = 0; i < ARRAY_SIZE(non_anon_test_cases); i++)
+ run_non_anon_test_case(&non_anon_test_cases[i]);
+}
+
+static int tests_per_non_anon_test_case(void)
+{
+ int tests = 3 + nr_hugetlbsizes;
+
+ if (thpsize)
+ tests += 1;
+ return tests;
+}
+
+int main(int argc, char **argv)
+{
+ int err;
+
+ pagesize = getpagesize();
+ detect_thpsize();
+ detect_hugetlbsizes();
+ detect_huge_zeropage();
+
+ ksft_print_header();
+ ksft_set_plan(ARRAY_SIZE(anon_test_cases) * tests_per_anon_test_case() +
+ ARRAY_SIZE(anon_thp_test_cases) * tests_per_anon_thp_test_case() +
+ ARRAY_SIZE(non_anon_test_cases) * tests_per_non_anon_test_case());
+
+ gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR);
+ pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
+ if (pagemap_fd < 0)
+ ksft_exit_fail_msg("opening pagemap failed\n");
+
+ run_anon_test_cases();
+ run_anon_thp_test_cases();
+ run_non_anon_test_cases();
+
+ err = ksft_get_fail_cnt();
+ if (err)
+ ksft_exit_fail_msg("%d out of %d tests failed\n",
+ err, ksft_test_num());
+ return ksft_exit_pass();
+}
diff --git a/tools/testing/selftests/mm/gup_test.c b/tools/testing/selftests/mm/gup_test.c
new file mode 100644
index 000000000000..e43879291dac
--- /dev/null
+++ b/tools/testing/selftests/mm/gup_test.c
@@ -0,0 +1,271 @@
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <pthread.h>
+#include <assert.h>
+#include <mm/gup_test.h>
+#include "../kselftest.h"
+
+#include "util.h"
+
+#define MB (1UL << 20)
+
+/* Just the flags we need, copied from mm.h: */
+#define FOLL_WRITE 0x01 /* check pte is writable */
+#define FOLL_TOUCH 0x02 /* mark page accessed */
+
+#define GUP_TEST_FILE "/sys/kernel/debug/gup_test"
+
+static unsigned long cmd = GUP_FAST_BENCHMARK;
+static int gup_fd, repeats = 1;
+static unsigned long size = 128 * MB;
+/* Serialize prints */
+static pthread_mutex_t print_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static char *cmd_to_str(unsigned long cmd)
+{
+ switch (cmd) {
+ case GUP_FAST_BENCHMARK:
+ return "GUP_FAST_BENCHMARK";
+ case PIN_FAST_BENCHMARK:
+ return "PIN_FAST_BENCHMARK";
+ case PIN_LONGTERM_BENCHMARK:
+ return "PIN_LONGTERM_BENCHMARK";
+ case GUP_BASIC_TEST:
+ return "GUP_BASIC_TEST";
+ case PIN_BASIC_TEST:
+ return "PIN_BASIC_TEST";
+ case DUMP_USER_PAGES_TEST:
+ return "DUMP_USER_PAGES_TEST";
+ }
+ return "Unknown command";
+}
+
+void *gup_thread(void *data)
+{
+ struct gup_test gup = *(struct gup_test *)data;
+ int i;
+
+ /* Only report timing information on the *_BENCHMARK commands: */
+ if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) ||
+ (cmd == PIN_LONGTERM_BENCHMARK)) {
+ for (i = 0; i < repeats; i++) {
+ gup.size = size;
+ if (ioctl(gup_fd, cmd, &gup))
+ perror("ioctl"), exit(1);
+
+ pthread_mutex_lock(&print_mutex);
+ printf("%s: Time: get:%lld put:%lld us",
+ cmd_to_str(cmd), gup.get_delta_usec,
+ gup.put_delta_usec);
+ if (gup.size != size)
+ printf(", truncated (size: %lld)", gup.size);
+ printf("\n");
+ pthread_mutex_unlock(&print_mutex);
+ }
+ } else {
+ gup.size = size;
+ if (ioctl(gup_fd, cmd, &gup)) {
+ perror("ioctl");
+ exit(1);
+ }
+
+ pthread_mutex_lock(&print_mutex);
+ printf("%s: done\n", cmd_to_str(cmd));
+ if (gup.size != size)
+ printf("Truncated (size: %lld)\n", gup.size);
+ pthread_mutex_unlock(&print_mutex);
+ }
+
+ return NULL;
+}
+
+int main(int argc, char **argv)
+{
+ struct gup_test gup = { 0 };
+ int filed, i, opt, nr_pages = 1, thp = -1, write = 1, nthreads = 1, ret;
+ int flags = MAP_PRIVATE, touch = 0;
+ char *file = "/dev/zero";
+ pthread_t *tid;
+ char *p;
+
+ while ((opt = getopt(argc, argv, "m:r:n:F:f:abcj:tTLUuwWSHpz")) != -1) {
+ switch (opt) {
+ case 'a':
+ cmd = PIN_FAST_BENCHMARK;
+ break;
+ case 'b':
+ cmd = PIN_BASIC_TEST;
+ break;
+ case 'L':
+ cmd = PIN_LONGTERM_BENCHMARK;
+ break;
+ case 'c':
+ cmd = DUMP_USER_PAGES_TEST;
+ /*
+ * Dump page 0 (index 1). May be overridden later, by
+ * user's non-option arguments.
+ *
+ * .which_pages is zero-based, so that zero can mean "do
+ * nothing".
+ */
+ gup.which_pages[0] = 1;
+ break;
+ case 'p':
+ /* works only with DUMP_USER_PAGES_TEST */
+ gup.test_flags |= GUP_TEST_FLAG_DUMP_PAGES_USE_PIN;
+ break;
+ case 'F':
+ /* strtol, so you can pass flags in hex form */
+ gup.gup_flags = strtol(optarg, 0, 0);
+ break;
+ case 'j':
+ nthreads = atoi(optarg);
+ break;
+ case 'm':
+ size = atoi(optarg) * MB;
+ break;
+ case 'r':
+ repeats = atoi(optarg);
+ break;
+ case 'n':
+ nr_pages = atoi(optarg);
+ break;
+ case 't':
+ thp = 1;
+ break;
+ case 'T':
+ thp = 0;
+ break;
+ case 'U':
+ cmd = GUP_BASIC_TEST;
+ break;
+ case 'u':
+ cmd = GUP_FAST_BENCHMARK;
+ break;
+ case 'w':
+ write = 1;
+ break;
+ case 'W':
+ write = 0;
+ break;
+ case 'f':
+ file = optarg;
+ break;
+ case 'S':
+ flags &= ~MAP_PRIVATE;
+ flags |= MAP_SHARED;
+ break;
+ case 'H':
+ flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
+ break;
+ case 'z':
+ /* fault pages in gup, do not fault in userland */
+ touch = 1;
+ break;
+ default:
+ return -1;
+ }
+ }
+
+ if (optind < argc) {
+ int extra_arg_count = 0;
+ /*
+ * For example:
+ *
+ * ./gup_test -c 0 1 0x1001
+ *
+ * ...to dump pages 0, 1, and 4097
+ */
+
+ while ((optind < argc) &&
+ (extra_arg_count < GUP_TEST_MAX_PAGES_TO_DUMP)) {
+ /*
+ * Do the 1-based indexing here, so that the user can
+ * use normal 0-based indexing on the command line.
+ */
+ long page_index = strtol(argv[optind], 0, 0) + 1;
+
+ gup.which_pages[extra_arg_count] = page_index;
+ extra_arg_count++;
+ optind++;
+ }
+ }
+
+ filed = open(file, O_RDWR|O_CREAT);
+ if (filed < 0) {
+ perror("open");
+ exit(filed);
+ }
+
+ gup.nr_pages_per_call = nr_pages;
+ if (write)
+ gup.gup_flags |= FOLL_WRITE;
+
+ gup_fd = open(GUP_TEST_FILE, O_RDWR);
+ if (gup_fd == -1) {
+ switch (errno) {
+ case EACCES:
+ if (getuid())
+ printf("Please run this test as root\n");
+ break;
+ case ENOENT:
+ if (opendir("/sys/kernel/debug") == NULL) {
+ printf("mount debugfs at /sys/kernel/debug\n");
+ break;
+ }
+ printf("check if CONFIG_GUP_TEST is enabled in kernel config\n");
+ break;
+ default:
+ perror("failed to open " GUP_TEST_FILE);
+ break;
+ }
+ exit(KSFT_SKIP);
+ }
+
+ p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
+ if (p == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+ gup.addr = (unsigned long)p;
+
+ if (thp == 1)
+ madvise(p, size, MADV_HUGEPAGE);
+ else if (thp == 0)
+ madvise(p, size, MADV_NOHUGEPAGE);
+
+ /*
+ * FOLL_TOUCH, in gup_test, is used as an either/or case: either
+ * fault pages in from the kernel via FOLL_TOUCH, or fault them
+ * in here, from user space. This allows comparison of performance
+ * between those two cases.
+ */
+ if (touch) {
+ gup.gup_flags |= FOLL_TOUCH;
+ } else {
+ for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
+ p[0] = 0;
+ }
+
+ tid = malloc(sizeof(pthread_t) * nthreads);
+ assert(tid);
+ for (i = 0; i < nthreads; i++) {
+ ret = pthread_create(&tid[i], NULL, gup_thread, &gup);
+ assert(ret == 0);
+ }
+ for (i = 0; i < nthreads; i++) {
+ ret = pthread_join(tid[i], NULL);
+ assert(ret == 0);
+ }
+ free(tid);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/hmm-tests.c b/tools/testing/selftests/mm/hmm-tests.c
new file mode 100644
index 000000000000..4adaad1b822f
--- /dev/null
+++ b/tools/testing/selftests/mm/hmm-tests.c
@@ -0,0 +1,2054 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * HMM stands for Heterogeneous Memory Management, it is a helper layer inside
+ * the linux kernel to help device drivers mirror a process address space in
+ * the device. This allows the device to use the same address space which
+ * makes communication and data exchange a lot easier.
+ *
+ * This framework's sole purpose is to exercise various code paths inside
+ * the kernel to make sure that HMM performs as expected and to flush out any
+ * bugs.
+ */
+
+#include "../kselftest_harness.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <strings.h>
+#include <time.h>
+#include <pthread.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <sys/ioctl.h>
+
+
+/*
+ * This is a private UAPI to the kernel test module so it isn't exported
+ * in the usual include/uapi/... directory.
+ */
+#include <lib/test_hmm_uapi.h>
+#include <mm/gup_test.h>
+
+struct hmm_buffer {
+ void *ptr;
+ void *mirror;
+ unsigned long size;
+ int fd;
+ uint64_t cpages;
+ uint64_t faults;
+};
+
+enum {
+ HMM_PRIVATE_DEVICE_ONE,
+ HMM_PRIVATE_DEVICE_TWO,
+ HMM_COHERENCE_DEVICE_ONE,
+ HMM_COHERENCE_DEVICE_TWO,
+};
+
+#define TWOMEG (1 << 21)
+#define HMM_BUFFER_SIZE (1024 << 12)
+#define HMM_PATH_MAX 64
+#define NTIMES 10
+
+#define ALIGN(x, a) (((x) + (a - 1)) & (~((a) - 1)))
+/* Just the flags we need, copied from mm.h: */
+#define FOLL_WRITE 0x01 /* check pte is writable */
+#define FOLL_LONGTERM 0x10000 /* mapping lifetime is indefinite */
+
+FIXTURE(hmm)
+{
+ int fd;
+ unsigned int page_size;
+ unsigned int page_shift;
+};
+
+FIXTURE_VARIANT(hmm)
+{
+ int device_number;
+};
+
+FIXTURE_VARIANT_ADD(hmm, hmm_device_private)
+{
+ .device_number = HMM_PRIVATE_DEVICE_ONE,
+};
+
+FIXTURE_VARIANT_ADD(hmm, hmm_device_coherent)
+{
+ .device_number = HMM_COHERENCE_DEVICE_ONE,
+};
+
+FIXTURE(hmm2)
+{
+ int fd0;
+ int fd1;
+ unsigned int page_size;
+ unsigned int page_shift;
+};
+
+FIXTURE_VARIANT(hmm2)
+{
+ int device_number0;
+ int device_number1;
+};
+
+FIXTURE_VARIANT_ADD(hmm2, hmm2_device_private)
+{
+ .device_number0 = HMM_PRIVATE_DEVICE_ONE,
+ .device_number1 = HMM_PRIVATE_DEVICE_TWO,
+};
+
+FIXTURE_VARIANT_ADD(hmm2, hmm2_device_coherent)
+{
+ .device_number0 = HMM_COHERENCE_DEVICE_ONE,
+ .device_number1 = HMM_COHERENCE_DEVICE_TWO,
+};
+
+static int hmm_open(int unit)
+{
+ char pathname[HMM_PATH_MAX];
+ int fd;
+
+ snprintf(pathname, sizeof(pathname), "/dev/hmm_dmirror%d", unit);
+ fd = open(pathname, O_RDWR, 0);
+ if (fd < 0)
+ fprintf(stderr, "could not open hmm dmirror driver (%s)\n",
+ pathname);
+ return fd;
+}
+
+static bool hmm_is_coherent_type(int dev_num)
+{
+ return (dev_num >= HMM_COHERENCE_DEVICE_ONE);
+}
+
+FIXTURE_SETUP(hmm)
+{
+ self->page_size = sysconf(_SC_PAGE_SIZE);
+ self->page_shift = ffs(self->page_size) - 1;
+
+ self->fd = hmm_open(variant->device_number);
+ if (self->fd < 0 && hmm_is_coherent_type(variant->device_number))
+ SKIP(exit(0), "DEVICE_COHERENT not available");
+ ASSERT_GE(self->fd, 0);
+}
+
+FIXTURE_SETUP(hmm2)
+{
+ self->page_size = sysconf(_SC_PAGE_SIZE);
+ self->page_shift = ffs(self->page_size) - 1;
+
+ self->fd0 = hmm_open(variant->device_number0);
+ if (self->fd0 < 0 && hmm_is_coherent_type(variant->device_number0))
+ SKIP(exit(0), "DEVICE_COHERENT not available");
+ ASSERT_GE(self->fd0, 0);
+ self->fd1 = hmm_open(variant->device_number1);
+ ASSERT_GE(self->fd1, 0);
+}
+
+FIXTURE_TEARDOWN(hmm)
+{
+ int ret = close(self->fd);
+
+ ASSERT_EQ(ret, 0);
+ self->fd = -1;
+}
+
+FIXTURE_TEARDOWN(hmm2)
+{
+ int ret = close(self->fd0);
+
+ ASSERT_EQ(ret, 0);
+ self->fd0 = -1;
+
+ ret = close(self->fd1);
+ ASSERT_EQ(ret, 0);
+ self->fd1 = -1;
+}
+
+static int hmm_dmirror_cmd(int fd,
+ unsigned long request,
+ struct hmm_buffer *buffer,
+ unsigned long npages)
+{
+ struct hmm_dmirror_cmd cmd;
+ int ret;
+
+ /* Simulate a device reading system memory. */
+ cmd.addr = (__u64)buffer->ptr;
+ cmd.ptr = (__u64)buffer->mirror;
+ cmd.npages = npages;
+
+ for (;;) {
+ ret = ioctl(fd, request, &cmd);
+ if (ret == 0)
+ break;
+ if (errno == EINTR)
+ continue;
+ return -errno;
+ }
+ buffer->cpages = cmd.cpages;
+ buffer->faults = cmd.faults;
+
+ return 0;
+}
+
+static void hmm_buffer_free(struct hmm_buffer *buffer)
+{
+ if (buffer == NULL)
+ return;
+
+ if (buffer->ptr)
+ munmap(buffer->ptr, buffer->size);
+ free(buffer->mirror);
+ free(buffer);
+}
+
+/*
+ * Create a temporary file that will be deleted on close.
+ */
+static int hmm_create_file(unsigned long size)
+{
+ char path[HMM_PATH_MAX];
+ int fd;
+
+ strcpy(path, "/tmp");
+ fd = open(path, O_TMPFILE | O_EXCL | O_RDWR, 0600);
+ if (fd >= 0) {
+ int r;
+
+ do {
+ r = ftruncate(fd, size);
+ } while (r == -1 && errno == EINTR);
+ if (!r)
+ return fd;
+ close(fd);
+ }
+ return -1;
+}
+
+/*
+ * Return a random unsigned number.
+ */
+static unsigned int hmm_random(void)
+{
+ static int fd = -1;
+ unsigned int r;
+
+ if (fd < 0) {
+ fd = open("/dev/urandom", O_RDONLY);
+ if (fd < 0) {
+ fprintf(stderr, "%s:%d failed to open /dev/urandom\n",
+ __FILE__, __LINE__);
+ return ~0U;
+ }
+ }
+ read(fd, &r, sizeof(r));
+ return r;
+}
+
+static void hmm_nanosleep(unsigned int n)
+{
+ struct timespec t;
+
+ t.tv_sec = 0;
+ t.tv_nsec = n;
+ nanosleep(&t, NULL);
+}
+
+static int hmm_migrate_sys_to_dev(int fd,
+ struct hmm_buffer *buffer,
+ unsigned long npages)
+{
+ return hmm_dmirror_cmd(fd, HMM_DMIRROR_MIGRATE_TO_DEV, buffer, npages);
+}
+
+static int hmm_migrate_dev_to_sys(int fd,
+ struct hmm_buffer *buffer,
+ unsigned long npages)
+{
+ return hmm_dmirror_cmd(fd, HMM_DMIRROR_MIGRATE_TO_SYS, buffer, npages);
+}
+
+/*
+ * Simple NULL test of device open/close.
+ */
+TEST_F(hmm, open_close)
+{
+}
+
+/*
+ * Read private anonymous memory.
+ */
+TEST_F(hmm, anon_read)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+ int val;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /*
+ * Initialize buffer in system memory but leave the first two pages
+ * zero (pte_none and pfn_zero).
+ */
+ i = 2 * self->page_size / sizeof(*ptr);
+ for (ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Set buffer permission to read-only. */
+ ret = mprotect(buffer->ptr, size, PROT_READ);
+ ASSERT_EQ(ret, 0);
+
+ /* Populate the CPU page table with a special zero page. */
+ val = *(int *)(buffer->ptr + self->page_size);
+ ASSERT_EQ(val, 0);
+
+ /* Simulate a device reading system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device read. */
+ ptr = buffer->mirror;
+ for (i = 0; i < 2 * self->page_size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], 0);
+ for (; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Read private anonymous memory which has been protected with
+ * mprotect() PROT_NONE.
+ */
+TEST_F(hmm, anon_read_prot)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Initialize mirror buffer so we can verify it isn't written. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = -i;
+
+ /* Protect buffer from reading. */
+ ret = mprotect(buffer->ptr, size, PROT_NONE);
+ ASSERT_EQ(ret, 0);
+
+ /* Simulate a device reading system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer, npages);
+ ASSERT_EQ(ret, -EFAULT);
+
+ /* Allow CPU to read the buffer so we can check it. */
+ ret = mprotect(buffer->ptr, size, PROT_READ);
+ ASSERT_EQ(ret, 0);
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], -i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Write private anonymous memory.
+ */
+TEST_F(hmm, anon_write)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize data that the device will write to buffer->ptr. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device wrote. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Write private anonymous memory which has been protected with
+ * mprotect() PROT_READ.
+ */
+TEST_F(hmm, anon_write_prot)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Simulate a device reading a zero page of memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer, 1);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, 1);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Initialize data that the device will write to buffer->ptr. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, -EPERM);
+
+ /* Check what the device wrote. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], 0);
+
+ /* Now allow writing and see that the zero page is replaced. */
+ ret = mprotect(buffer->ptr, size, PROT_WRITE | PROT_READ);
+ ASSERT_EQ(ret, 0);
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device wrote. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Check that a device writing an anonymous private mapping
+ * will copy-on-write if a child process inherits the mapping.
+ */
+TEST_F(hmm, anon_write_child)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ pid_t pid;
+ int child_fd;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer->ptr so we can tell if it is written. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Initialize data that the device will write to buffer->ptr. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = -i;
+
+ pid = fork();
+ if (pid == -1)
+ ASSERT_EQ(pid, 0);
+ if (pid != 0) {
+ waitpid(pid, &ret, 0);
+ ASSERT_EQ(WIFEXITED(ret), 1);
+
+ /* Check that the parent's buffer did not change. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+ return;
+ }
+
+ /* Check that we see the parent's values. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], -i);
+
+ /* The child process needs its own mirror to its own mm. */
+ child_fd = hmm_open(0);
+ ASSERT_GE(child_fd, 0);
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(child_fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device wrote. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], -i);
+
+ close(child_fd);
+ exit(0);
+}
+
+/*
+ * Check that a device writing an anonymous shared mapping
+ * will not copy-on-write if a child process inherits the mapping.
+ */
+TEST_F(hmm, anon_write_child_shared)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ pid_t pid;
+ int child_fd;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer->ptr so we can tell if it is written. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Initialize data that the device will write to buffer->ptr. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = -i;
+
+ pid = fork();
+ if (pid == -1)
+ ASSERT_EQ(pid, 0);
+ if (pid != 0) {
+ waitpid(pid, &ret, 0);
+ ASSERT_EQ(WIFEXITED(ret), 1);
+
+ /* Check that the parent's buffer did change. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], -i);
+ return;
+ }
+
+ /* Check that we see the parent's values. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], -i);
+
+ /* The child process needs its own mirror to its own mm. */
+ child_fd = hmm_open(0);
+ ASSERT_GE(child_fd, 0);
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(child_fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device wrote. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], -i);
+
+ close(child_fd);
+ exit(0);
+}
+
+/*
+ * Write private anonymous huge page.
+ */
+TEST_F(hmm, anon_write_huge)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ void *old_ptr;
+ void *map;
+ int *ptr;
+ int ret;
+
+ size = 2 * TWOMEG;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ size = TWOMEG;
+ npages = size >> self->page_shift;
+ map = (void *)ALIGN((uintptr_t)buffer->ptr, size);
+ ret = madvise(map, size, MADV_HUGEPAGE);
+ ASSERT_EQ(ret, 0);
+ old_ptr = buffer->ptr;
+ buffer->ptr = map;
+
+ /* Initialize data that the device will write to buffer->ptr. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device wrote. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ buffer->ptr = old_ptr;
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Read numeric data from raw and tagged kernel status files. Used to read
+ * /proc and /sys data (without a tag) and from /proc/meminfo (with a tag).
+ */
+static long file_read_ulong(char *file, const char *tag)
+{
+ int fd;
+ char buf[2048];
+ int len;
+ char *p, *q;
+ long val;
+
+ fd = open(file, O_RDONLY);
+ if (fd < 0) {
+ /* Error opening the file */
+ return -1;
+ }
+
+ len = read(fd, buf, sizeof(buf));
+ close(fd);
+ if (len < 0) {
+ /* Error in reading the file */
+ return -1;
+ }
+ if (len == sizeof(buf)) {
+ /* Error file is too large */
+ return -1;
+ }
+ buf[len] = '\0';
+
+ /* Search for a tag if provided */
+ if (tag) {
+ p = strstr(buf, tag);
+ if (!p)
+ return -1; /* looks like the line we want isn't there */
+ p += strlen(tag);
+ } else
+ p = buf;
+
+ val = strtol(p, &q, 0);
+ if (*q != ' ') {
+ /* Error parsing the file */
+ return -1;
+ }
+
+ return val;
+}
+
+/*
+ * Write huge TLBFS page.
+ */
+TEST_F(hmm, anon_write_hugetlbfs)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long default_hsize;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ default_hsize = file_read_ulong("/proc/meminfo", "Hugepagesize:");
+ if (default_hsize < 0 || default_hsize*1024 < default_hsize)
+ SKIP(return, "Huge page size could not be determined");
+ default_hsize = default_hsize*1024; /* KB to B */
+
+ size = ALIGN(TWOMEG, default_hsize);
+ npages = size >> self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
+ -1, 0);
+ if (buffer->ptr == MAP_FAILED) {
+ free(buffer);
+ SKIP(return, "Huge page could not be allocated");
+ }
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ /* Initialize data that the device will write to buffer->ptr. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device wrote. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ munmap(buffer->ptr, buffer->size);
+ buffer->ptr = NULL;
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Read mmap'ed file memory.
+ */
+TEST_F(hmm, file_read)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+ int fd;
+ ssize_t len;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ fd = hmm_create_file(size);
+ ASSERT_GE(fd, 0);
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = fd;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ /* Write initial contents of the file. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+ len = pwrite(fd, buffer->mirror, size, 0);
+ ASSERT_EQ(len, size);
+ memset(buffer->mirror, 0, size);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ,
+ MAP_SHARED,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Simulate a device reading system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Write mmap'ed file memory.
+ */
+TEST_F(hmm, file_write)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+ int fd;
+ ssize_t len;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ fd = hmm_create_file(size);
+ ASSERT_GE(fd, 0);
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = fd;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize data that the device will write to buffer->ptr. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device wrote. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Check that the device also wrote the file. */
+ len = pread(fd, buffer->mirror, size, 0);
+ ASSERT_EQ(len, size);
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Migrate anonymous memory to device private memory.
+ */
+TEST_F(hmm, migrate)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Migrate memory to device. */
+ ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Migrate anonymous memory to device private memory and fault some of it back
+ * to system memory, then try migrating the resulting mix of system and device
+ * private memory to the device.
+ */
+TEST_F(hmm, migrate_fault)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Migrate memory to device. */
+ ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Fault half the pages back to system memory and check them. */
+ for (i = 0, ptr = buffer->ptr; i < size / (2 * sizeof(*ptr)); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Migrate memory to the device again. */
+ ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+TEST_F(hmm, migrate_release)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Migrate memory to device. */
+ ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Release device memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_RELEASE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+
+ /* Fault pages back to system memory and check them. */
+ for (i = 0, ptr = buffer->ptr; i < size / (2 * sizeof(*ptr)); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Migrate anonymous shared memory to device private memory.
+ */
+TEST_F(hmm, migrate_shared)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Migrate memory to device. */
+ ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
+ ASSERT_EQ(ret, -ENOENT);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Try to migrate various memory types to device private memory.
+ */
+TEST_F(hmm2, migrate_mixed)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ int *ptr;
+ unsigned char *p;
+ int ret;
+ int val;
+
+ npages = 6;
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ /* Reserve a range of addresses. */
+ buffer->ptr = mmap(NULL, size,
+ PROT_NONE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+ p = buffer->ptr;
+
+ /* Migrating a protected area should be an error. */
+ ret = hmm_migrate_sys_to_dev(self->fd1, buffer, npages);
+ ASSERT_EQ(ret, -EINVAL);
+
+ /* Punch a hole after the first page address. */
+ ret = munmap(buffer->ptr + self->page_size, self->page_size);
+ ASSERT_EQ(ret, 0);
+
+ /* We expect an error if the vma doesn't cover the range. */
+ ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 3);
+ ASSERT_EQ(ret, -EINVAL);
+
+ /* Page 2 will be a read-only zero page. */
+ ret = mprotect(buffer->ptr + 2 * self->page_size, self->page_size,
+ PROT_READ);
+ ASSERT_EQ(ret, 0);
+ ptr = (int *)(buffer->ptr + 2 * self->page_size);
+ val = *ptr + 3;
+ ASSERT_EQ(val, 3);
+
+ /* Page 3 will be read-only. */
+ ret = mprotect(buffer->ptr + 3 * self->page_size, self->page_size,
+ PROT_READ | PROT_WRITE);
+ ASSERT_EQ(ret, 0);
+ ptr = (int *)(buffer->ptr + 3 * self->page_size);
+ *ptr = val;
+ ret = mprotect(buffer->ptr + 3 * self->page_size, self->page_size,
+ PROT_READ);
+ ASSERT_EQ(ret, 0);
+
+ /* Page 4-5 will be read-write. */
+ ret = mprotect(buffer->ptr + 4 * self->page_size, 2 * self->page_size,
+ PROT_READ | PROT_WRITE);
+ ASSERT_EQ(ret, 0);
+ ptr = (int *)(buffer->ptr + 4 * self->page_size);
+ *ptr = val;
+ ptr = (int *)(buffer->ptr + 5 * self->page_size);
+ *ptr = val;
+
+ /* Now try to migrate pages 2-5 to device 1. */
+ buffer->ptr = p + 2 * self->page_size;
+ ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 4);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, 4);
+
+ /* Page 5 won't be migrated to device 0 because it's on device 1. */
+ buffer->ptr = p + 5 * self->page_size;
+ ret = hmm_migrate_sys_to_dev(self->fd0, buffer, 1);
+ ASSERT_EQ(ret, -ENOENT);
+ buffer->ptr = p;
+
+ buffer->ptr = p;
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Migrate anonymous memory to device memory and back to system memory
+ * multiple times. In case of private zone configuration, this is done
+ * through fault pages accessed by CPU. In case of coherent zone configuration,
+ * the pages from the device should be explicitly migrated back to system memory.
+ * The reason is Coherent device zone has coherent access by CPU, therefore
+ * it will not generate any page fault.
+ */
+TEST_F(hmm, migrate_multiple)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ unsigned long c;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ for (c = 0; c < NTIMES; c++) {
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Migrate memory to device. */
+ ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Migrate back to system memory and check them. */
+ if (hmm_is_coherent_type(variant->device_number)) {
+ ret = hmm_migrate_dev_to_sys(self->fd, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ }
+
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+ }
+}
+
+/*
+ * Read anonymous memory multiple times.
+ */
+TEST_F(hmm, anon_read_multiple)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ unsigned long c;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ for (c = 0; c < NTIMES; c++) {
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i + c;
+
+ /* Simulate a device reading system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer,
+ npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i + c);
+
+ hmm_buffer_free(buffer);
+ }
+}
+
+void *unmap_buffer(void *p)
+{
+ struct hmm_buffer *buffer = p;
+
+ /* Delay for a bit and then unmap buffer while it is being read. */
+ hmm_nanosleep(hmm_random() % 32000);
+ munmap(buffer->ptr + buffer->size / 2, buffer->size / 2);
+ buffer->ptr = NULL;
+
+ return NULL;
+}
+
+/*
+ * Try reading anonymous memory while it is being unmapped.
+ */
+TEST_F(hmm, anon_teardown)
+{
+ unsigned long npages;
+ unsigned long size;
+ unsigned long c;
+ void *ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ for (c = 0; c < NTIMES; ++c) {
+ pthread_t thread;
+ struct hmm_buffer *buffer;
+ unsigned long i;
+ int *ptr;
+ int rc;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i + c;
+
+ rc = pthread_create(&thread, NULL, unmap_buffer, buffer);
+ ASSERT_EQ(rc, 0);
+
+ /* Simulate a device reading system memory. */
+ rc = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_READ, buffer,
+ npages);
+ if (rc == 0) {
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror;
+ i < size / sizeof(*ptr);
+ ++i)
+ ASSERT_EQ(ptr[i], i + c);
+ }
+
+ pthread_join(thread, &ret);
+ hmm_buffer_free(buffer);
+ }
+}
+
+/*
+ * Test memory snapshot without faulting in pages accessed by the device.
+ */
+TEST_F(hmm, mixedmap)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned char *m;
+ int ret;
+
+ npages = 1;
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(npages);
+ ASSERT_NE(buffer->mirror, NULL);
+
+
+ /* Reserve a range of addresses. */
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE,
+ self->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Simulate a device snapshotting CPU pagetables. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device saw. */
+ m = buffer->mirror;
+ ASSERT_EQ(m[0], HMM_DMIRROR_PROT_READ);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Test memory snapshot without faulting in pages accessed by the device.
+ */
+TEST_F(hmm2, snapshot)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ int *ptr;
+ unsigned char *p;
+ unsigned char *m;
+ int ret;
+ int val;
+
+ npages = 7;
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(npages);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ /* Reserve a range of addresses. */
+ buffer->ptr = mmap(NULL, size,
+ PROT_NONE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+ p = buffer->ptr;
+
+ /* Punch a hole after the first page address. */
+ ret = munmap(buffer->ptr + self->page_size, self->page_size);
+ ASSERT_EQ(ret, 0);
+
+ /* Page 2 will be read-only zero page. */
+ ret = mprotect(buffer->ptr + 2 * self->page_size, self->page_size,
+ PROT_READ);
+ ASSERT_EQ(ret, 0);
+ ptr = (int *)(buffer->ptr + 2 * self->page_size);
+ val = *ptr + 3;
+ ASSERT_EQ(val, 3);
+
+ /* Page 3 will be read-only. */
+ ret = mprotect(buffer->ptr + 3 * self->page_size, self->page_size,
+ PROT_READ | PROT_WRITE);
+ ASSERT_EQ(ret, 0);
+ ptr = (int *)(buffer->ptr + 3 * self->page_size);
+ *ptr = val;
+ ret = mprotect(buffer->ptr + 3 * self->page_size, self->page_size,
+ PROT_READ);
+ ASSERT_EQ(ret, 0);
+
+ /* Page 4-6 will be read-write. */
+ ret = mprotect(buffer->ptr + 4 * self->page_size, 3 * self->page_size,
+ PROT_READ | PROT_WRITE);
+ ASSERT_EQ(ret, 0);
+ ptr = (int *)(buffer->ptr + 4 * self->page_size);
+ *ptr = val;
+
+ /* Page 5 will be migrated to device 0. */
+ buffer->ptr = p + 5 * self->page_size;
+ ret = hmm_migrate_sys_to_dev(self->fd0, buffer, 1);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, 1);
+
+ /* Page 6 will be migrated to device 1. */
+ buffer->ptr = p + 6 * self->page_size;
+ ret = hmm_migrate_sys_to_dev(self->fd1, buffer, 1);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, 1);
+
+ /* Simulate a device snapshotting CPU pagetables. */
+ buffer->ptr = p;
+ ret = hmm_dmirror_cmd(self->fd0, HMM_DMIRROR_SNAPSHOT, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device saw. */
+ m = buffer->mirror;
+ ASSERT_EQ(m[0], HMM_DMIRROR_PROT_ERROR);
+ ASSERT_EQ(m[1], HMM_DMIRROR_PROT_ERROR);
+ ASSERT_EQ(m[2], HMM_DMIRROR_PROT_ZERO | HMM_DMIRROR_PROT_READ);
+ ASSERT_EQ(m[3], HMM_DMIRROR_PROT_READ);
+ ASSERT_EQ(m[4], HMM_DMIRROR_PROT_WRITE);
+ if (!hmm_is_coherent_type(variant->device_number0)) {
+ ASSERT_EQ(m[5], HMM_DMIRROR_PROT_DEV_PRIVATE_LOCAL |
+ HMM_DMIRROR_PROT_WRITE);
+ ASSERT_EQ(m[6], HMM_DMIRROR_PROT_NONE);
+ } else {
+ ASSERT_EQ(m[5], HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL |
+ HMM_DMIRROR_PROT_WRITE);
+ ASSERT_EQ(m[6], HMM_DMIRROR_PROT_DEV_COHERENT_REMOTE |
+ HMM_DMIRROR_PROT_WRITE);
+ }
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Test the hmm_range_fault() HMM_PFN_PMD flag for large pages that
+ * should be mapped by a large page table entry.
+ */
+TEST_F(hmm, compound)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long default_hsize;
+ int *ptr;
+ unsigned char *m;
+ int ret;
+ unsigned long i;
+
+ /* Skip test if we can't allocate a hugetlbfs page. */
+
+ default_hsize = file_read_ulong("/proc/meminfo", "Hugepagesize:");
+ if (default_hsize < 0 || default_hsize*1024 < default_hsize)
+ SKIP(return, "Huge page size could not be determined");
+ default_hsize = default_hsize*1024; /* KB to B */
+
+ size = ALIGN(TWOMEG, default_hsize);
+ npages = size >> self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
+ -1, 0);
+ if (buffer->ptr == MAP_FAILED) {
+ free(buffer);
+ return;
+ }
+
+ buffer->size = size;
+ buffer->mirror = malloc(npages);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ /* Initialize the pages the device will snapshot in buffer->ptr. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Simulate a device snapshotting CPU pagetables. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device saw. */
+ m = buffer->mirror;
+ for (i = 0; i < npages; ++i)
+ ASSERT_EQ(m[i], HMM_DMIRROR_PROT_WRITE |
+ HMM_DMIRROR_PROT_PMD);
+
+ /* Make the region read-only. */
+ ret = mprotect(buffer->ptr, size, PROT_READ);
+ ASSERT_EQ(ret, 0);
+
+ /* Simulate a device snapshotting CPU pagetables. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device saw. */
+ m = buffer->mirror;
+ for (i = 0; i < npages; ++i)
+ ASSERT_EQ(m[i], HMM_DMIRROR_PROT_READ |
+ HMM_DMIRROR_PROT_PMD);
+
+ munmap(buffer->ptr, buffer->size);
+ buffer->ptr = NULL;
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Test two devices reading the same memory (double mapped).
+ */
+TEST_F(hmm2, double_map)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = 6;
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(npages);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ /* Reserve a range of addresses. */
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Make region read-only. */
+ ret = mprotect(buffer->ptr, size, PROT_READ);
+ ASSERT_EQ(ret, 0);
+
+ /* Simulate device 0 reading system memory. */
+ ret = hmm_dmirror_cmd(self->fd0, HMM_DMIRROR_READ, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Simulate device 1 reading system memory. */
+ ret = hmm_dmirror_cmd(self->fd1, HMM_DMIRROR_READ, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Migrate pages to device 1 and try to read from device 0. */
+ ret = hmm_migrate_sys_to_dev(self->fd1, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ ret = hmm_dmirror_cmd(self->fd0, HMM_DMIRROR_READ, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ ASSERT_EQ(buffer->faults, 1);
+
+ /* Check what device 0 read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Basic check of exclusive faulting.
+ */
+TEST_F(hmm, exclusive)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Map memory exclusively for device access. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_EXCLUSIVE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ /* Fault pages back to system memory and check them. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i]++, i);
+
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i+1);
+
+ /* Check atomic access revoked */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_CHECK_EXCLUSIVE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+
+ hmm_buffer_free(buffer);
+}
+
+TEST_F(hmm, exclusive_mprotect)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Map memory exclusively for device access. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_EXCLUSIVE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ ret = mprotect(buffer->ptr, size, PROT_READ);
+ ASSERT_EQ(ret, 0);
+
+ /* Simulate a device writing system memory. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_WRITE, buffer, npages);
+ ASSERT_EQ(ret, -EPERM);
+
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Check copy-on-write works.
+ */
+TEST_F(hmm, exclusive_cow)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+
+ npages = ALIGN(HMM_BUFFER_SIZE, self->page_size) >> self->page_shift;
+ ASSERT_NE(npages, 0);
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Map memory exclusively for device access. */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_EXCLUSIVE, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ fork();
+
+ /* Fault pages back to system memory and check them. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i]++, i);
+
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i+1);
+
+ hmm_buffer_free(buffer);
+}
+
+static int gup_test_exec(int gup_fd, unsigned long addr, int cmd,
+ int npages, int size, int flags)
+{
+ struct gup_test gup = {
+ .nr_pages_per_call = npages,
+ .addr = addr,
+ .gup_flags = FOLL_WRITE | flags,
+ .size = size,
+ };
+
+ if (ioctl(gup_fd, cmd, &gup)) {
+ perror("ioctl on error\n");
+ return errno;
+ }
+
+ return 0;
+}
+
+/*
+ * Test get user device pages through gup_test. Setting PIN_LONGTERM flag.
+ * This should trigger a migration back to system memory for both, private
+ * and coherent type pages.
+ * This test makes use of gup_test module. Make sure GUP_TEST_CONFIG is added
+ * to your configuration before you run it.
+ */
+TEST_F(hmm, hmm_gup_test)
+{
+ struct hmm_buffer *buffer;
+ int gup_fd;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+ unsigned char *m;
+
+ gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR);
+ if (gup_fd == -1)
+ SKIP(return, "Skipping test, could not find gup_test driver");
+
+ npages = 4;
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Migrate memory to device. */
+ ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ /* Check what the device read. */
+ for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ ASSERT_EQ(gup_test_exec(gup_fd,
+ (unsigned long)buffer->ptr,
+ GUP_BASIC_TEST, 1, self->page_size, 0), 0);
+ ASSERT_EQ(gup_test_exec(gup_fd,
+ (unsigned long)buffer->ptr + 1 * self->page_size,
+ GUP_FAST_BENCHMARK, 1, self->page_size, 0), 0);
+ ASSERT_EQ(gup_test_exec(gup_fd,
+ (unsigned long)buffer->ptr + 2 * self->page_size,
+ PIN_FAST_BENCHMARK, 1, self->page_size, FOLL_LONGTERM), 0);
+ ASSERT_EQ(gup_test_exec(gup_fd,
+ (unsigned long)buffer->ptr + 3 * self->page_size,
+ PIN_LONGTERM_BENCHMARK, 1, self->page_size, 0), 0);
+
+ /* Take snapshot to CPU pagetables */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ m = buffer->mirror;
+ if (hmm_is_coherent_type(variant->device_number)) {
+ ASSERT_EQ(HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL | HMM_DMIRROR_PROT_WRITE, m[0]);
+ ASSERT_EQ(HMM_DMIRROR_PROT_DEV_COHERENT_LOCAL | HMM_DMIRROR_PROT_WRITE, m[1]);
+ } else {
+ ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[0]);
+ ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[1]);
+ }
+ ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[2]);
+ ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[3]);
+ /*
+ * Check again the content on the pages. Make sure there's no
+ * corrupted data.
+ */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ASSERT_EQ(ptr[i], i);
+
+ close(gup_fd);
+ hmm_buffer_free(buffer);
+}
+
+/*
+ * Test copy-on-write in device pages.
+ * In case of writing to COW private page(s), a page fault will migrate pages
+ * back to system memory first. Then, these pages will be duplicated. In case
+ * of COW device coherent type, pages are duplicated directly from device
+ * memory.
+ */
+TEST_F(hmm, hmm_cow_in_device)
+{
+ struct hmm_buffer *buffer;
+ unsigned long npages;
+ unsigned long size;
+ unsigned long i;
+ int *ptr;
+ int ret;
+ unsigned char *m;
+ pid_t pid;
+ int status;
+
+ npages = 4;
+ size = npages << self->page_shift;
+
+ buffer = malloc(sizeof(*buffer));
+ ASSERT_NE(buffer, NULL);
+
+ buffer->fd = -1;
+ buffer->size = size;
+ buffer->mirror = malloc(size);
+ ASSERT_NE(buffer->mirror, NULL);
+
+ buffer->ptr = mmap(NULL, size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS,
+ buffer->fd, 0);
+ ASSERT_NE(buffer->ptr, MAP_FAILED);
+
+ /* Initialize buffer in system memory. */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Migrate memory to device. */
+
+ ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+
+ pid = fork();
+ if (pid == -1)
+ ASSERT_EQ(pid, 0);
+ if (!pid) {
+ /* Child process waitd for SIGTERM from the parent. */
+ while (1) {
+ }
+ perror("Should not reach this\n");
+ exit(0);
+ }
+ /* Parent process writes to COW pages(s) and gets a
+ * new copy in system. In case of device private pages,
+ * this write causes a migration to system mem first.
+ */
+ for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
+ ptr[i] = i;
+
+ /* Terminate child and wait */
+ EXPECT_EQ(0, kill(pid, SIGTERM));
+ EXPECT_EQ(pid, waitpid(pid, &status, 0));
+ EXPECT_NE(0, WIFSIGNALED(status));
+ EXPECT_EQ(SIGTERM, WTERMSIG(status));
+
+ /* Take snapshot to CPU pagetables */
+ ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
+ ASSERT_EQ(ret, 0);
+ ASSERT_EQ(buffer->cpages, npages);
+ m = buffer->mirror;
+ for (i = 0; i < npages; i++)
+ ASSERT_EQ(HMM_DMIRROR_PROT_WRITE, m[i]);
+
+ hmm_buffer_free(buffer);
+}
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/mm/hugepage-mmap.c b/tools/testing/selftests/mm/hugepage-mmap.c
new file mode 100644
index 000000000000..955ef87f382c
--- /dev/null
+++ b/tools/testing/selftests/mm/hugepage-mmap.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * hugepage-mmap:
+ *
+ * Example of using huge page memory in a user application using the mmap
+ * system call. Before running this application, make sure that the
+ * administrator has mounted the hugetlbfs filesystem (on some directory
+ * like /mnt) using the command mount -t hugetlbfs nodev /mnt. In this
+ * example, the app is requesting memory of size 256MB that is backed by
+ * huge pages.
+ *
+ * For the ia64 architecture, the Linux kernel reserves Region number 4 for
+ * huge pages. That means that if one requires a fixed address, a huge page
+ * aligned address starting with 0x800000... will be required. If a fixed
+ * address is not required, the kernel will select an address in the proper
+ * range.
+ * Other architectures, such as ppc64, i386 or x86_64 are not so constrained.
+ */
+#define _GNU_SOURCE
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+
+#define LENGTH (256UL*1024*1024)
+#define PROTECTION (PROT_READ | PROT_WRITE)
+
+/* Only ia64 requires this */
+#ifdef __ia64__
+#define ADDR (void *)(0x8000000000000000UL)
+#define FLAGS (MAP_SHARED | MAP_FIXED)
+#else
+#define ADDR (void *)(0x0UL)
+#define FLAGS (MAP_SHARED)
+#endif
+
+static void check_bytes(char *addr)
+{
+ printf("First hex is %x\n", *((unsigned int *)addr));
+}
+
+static void write_bytes(char *addr)
+{
+ unsigned long i;
+
+ for (i = 0; i < LENGTH; i++)
+ *(addr + i) = (char)i;
+}
+
+static int read_bytes(char *addr)
+{
+ unsigned long i;
+
+ check_bytes(addr);
+ for (i = 0; i < LENGTH; i++)
+ if (*(addr + i) != (char)i) {
+ printf("Mismatch at %lu\n", i);
+ return 1;
+ }
+ return 0;
+}
+
+int main(void)
+{
+ void *addr;
+ int fd, ret;
+
+ fd = memfd_create("hugepage-mmap", MFD_HUGETLB);
+ if (fd < 0) {
+ perror("memfd_create() failed");
+ exit(1);
+ }
+
+ addr = mmap(ADDR, LENGTH, PROTECTION, FLAGS, fd, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ close(fd);
+ exit(1);
+ }
+
+ printf("Returned address is %p\n", addr);
+ check_bytes(addr);
+ write_bytes(addr);
+ ret = read_bytes(addr);
+
+ munmap(addr, LENGTH);
+ close(fd);
+
+ return ret;
+}
diff --git a/tools/testing/selftests/mm/hugepage-mremap.c b/tools/testing/selftests/mm/hugepage-mremap.c
new file mode 100644
index 000000000000..e53b5eaa8fce
--- /dev/null
+++ b/tools/testing/selftests/mm/hugepage-mremap.c
@@ -0,0 +1,188 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * hugepage-mremap:
+ *
+ * Example of remapping huge page memory in a user application using the
+ * mremap system call. The path to a file in a hugetlbfs filesystem must
+ * be passed as the last argument to this test. The amount of memory used
+ * by this test in MBs can optionally be passed as an argument. If no memory
+ * amount is passed, the default amount is 10MB.
+ *
+ * To make sure the test triggers pmd sharing and goes through the 'unshare'
+ * path in the mremap code use 1GB (1024) or more.
+ */
+
+#define _GNU_SOURCE
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <errno.h>
+#include <fcntl.h> /* Definition of O_* constants */
+#include <sys/syscall.h> /* Definition of SYS_* constants */
+#include <linux/userfaultfd.h>
+#include <sys/ioctl.h>
+#include <string.h>
+
+#define DEFAULT_LENGTH_MB 10UL
+#define MB_TO_BYTES(x) (x * 1024 * 1024)
+
+#define PROTECTION (PROT_READ | PROT_WRITE | PROT_EXEC)
+#define FLAGS (MAP_SHARED | MAP_ANONYMOUS)
+
+static void check_bytes(char *addr)
+{
+ printf("First hex is %x\n", *((unsigned int *)addr));
+}
+
+static void write_bytes(char *addr, size_t len)
+{
+ unsigned long i;
+
+ for (i = 0; i < len; i++)
+ *(addr + i) = (char)i;
+}
+
+static int read_bytes(char *addr, size_t len)
+{
+ unsigned long i;
+
+ check_bytes(addr);
+ for (i = 0; i < len; i++)
+ if (*(addr + i) != (char)i) {
+ printf("Mismatch at %lu\n", i);
+ return 1;
+ }
+ return 0;
+}
+
+static void register_region_with_uffd(char *addr, size_t len)
+{
+ long uffd; /* userfaultfd file descriptor */
+ struct uffdio_api uffdio_api;
+ struct uffdio_register uffdio_register;
+
+ /* Create and enable userfaultfd object. */
+
+ uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
+ if (uffd == -1) {
+ perror("userfaultfd");
+ exit(1);
+ }
+
+ uffdio_api.api = UFFD_API;
+ uffdio_api.features = 0;
+ if (ioctl(uffd, UFFDIO_API, &uffdio_api) == -1) {
+ perror("ioctl-UFFDIO_API");
+ exit(1);
+ }
+
+ /* Create a private anonymous mapping. The memory will be
+ * demand-zero paged--that is, not yet allocated. When we
+ * actually touch the memory, it will be allocated via
+ * the userfaultfd.
+ */
+
+ addr = mmap(NULL, len, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+
+ printf("Address returned by mmap() = %p\n", addr);
+
+ /* Register the memory range of the mapping we just created for
+ * handling by the userfaultfd object. In mode, we request to track
+ * missing pages (i.e., pages that have not yet been faulted in).
+ */
+
+ uffdio_register.range.start = (unsigned long)addr;
+ uffdio_register.range.len = len;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) == -1) {
+ perror("ioctl-UFFDIO_REGISTER");
+ exit(1);
+ }
+}
+
+int main(int argc, char *argv[])
+{
+ size_t length = 0;
+ int ret = 0, fd;
+
+ if (argc >= 2 && !strcmp(argv[1], "-h")) {
+ printf("Usage: %s [length_in_MB]\n", argv[0]);
+ exit(1);
+ }
+
+ /* Read memory length as the first arg if valid, otherwise fallback to
+ * the default length.
+ */
+ if (argc >= 2)
+ length = (size_t)atoi(argv[1]);
+ else
+ length = DEFAULT_LENGTH_MB;
+
+ length = MB_TO_BYTES(length);
+ fd = memfd_create(argv[0], MFD_HUGETLB);
+ if (fd < 0) {
+ perror("Open failed");
+ exit(1);
+ }
+
+ /* mmap to a PUD aligned address to hopefully trigger pmd sharing. */
+ unsigned long suggested_addr = 0x7eaa40000000;
+ void *haddr = mmap((void *)suggested_addr, length, PROTECTION,
+ MAP_HUGETLB | MAP_SHARED | MAP_POPULATE, fd, 0);
+ printf("Map haddr: Returned address is %p\n", haddr);
+ if (haddr == MAP_FAILED) {
+ perror("mmap1");
+ exit(1);
+ }
+
+ /* mmap again to a dummy address to hopefully trigger pmd sharing. */
+ suggested_addr = 0x7daa40000000;
+ void *daddr = mmap((void *)suggested_addr, length, PROTECTION,
+ MAP_HUGETLB | MAP_SHARED | MAP_POPULATE, fd, 0);
+ printf("Map daddr: Returned address is %p\n", daddr);
+ if (daddr == MAP_FAILED) {
+ perror("mmap3");
+ exit(1);
+ }
+
+ suggested_addr = 0x7faa40000000;
+ void *vaddr =
+ mmap((void *)suggested_addr, length, PROTECTION, FLAGS, -1, 0);
+ printf("Map vaddr: Returned address is %p\n", vaddr);
+ if (vaddr == MAP_FAILED) {
+ perror("mmap2");
+ exit(1);
+ }
+
+ register_region_with_uffd(haddr, length);
+
+ void *addr = mremap(haddr, length, length,
+ MREMAP_MAYMOVE | MREMAP_FIXED, vaddr);
+ if (addr == MAP_FAILED) {
+ perror("mremap");
+ exit(1);
+ }
+
+ printf("Mremap: Returned address is %p\n", addr);
+ check_bytes(addr);
+ write_bytes(addr, length);
+ ret = read_bytes(addr, length);
+
+ munmap(addr, length);
+
+ addr = mremap(addr, length, length, 0);
+ if (addr != MAP_FAILED) {
+ printf("mremap: Expected failure, but call succeeded\n");
+ exit(1);
+ }
+
+ close(fd);
+
+ return ret;
+}
diff --git a/tools/testing/selftests/mm/hugepage-shm.c b/tools/testing/selftests/mm/hugepage-shm.c
new file mode 100644
index 000000000000..e2527f32005b
--- /dev/null
+++ b/tools/testing/selftests/mm/hugepage-shm.c
@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * hugepage-shm:
+ *
+ * Example of using huge page memory in a user application using Sys V shared
+ * memory system calls. In this example the app is requesting 256MB of
+ * memory that is backed by huge pages. The application uses the flag
+ * SHM_HUGETLB in the shmget system call to inform the kernel that it is
+ * requesting huge pages.
+ *
+ * For the ia64 architecture, the Linux kernel reserves Region number 4 for
+ * huge pages. That means that if one requires a fixed address, a huge page
+ * aligned address starting with 0x800000... will be required. If a fixed
+ * address is not required, the kernel will select an address in the proper
+ * range.
+ * Other architectures, such as ppc64, i386 or x86_64 are not so constrained.
+ *
+ * Note: The default shared memory limit is quite low on many kernels,
+ * you may need to increase it via:
+ *
+ * echo 268435456 > /proc/sys/kernel/shmmax
+ *
+ * This will increase the maximum size per shared memory segment to 256MB.
+ * The other limit that you will hit eventually is shmall which is the
+ * total amount of shared memory in pages. To set it to 16GB on a system
+ * with a 4kB pagesize do:
+ *
+ * echo 4194304 > /proc/sys/kernel/shmall
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#include <sys/mman.h>
+
+#ifndef SHM_HUGETLB
+#define SHM_HUGETLB 04000
+#endif
+
+#define LENGTH (256UL*1024*1024)
+
+#define dprintf(x) printf(x)
+
+/* Only ia64 requires this */
+#ifdef __ia64__
+#define ADDR (void *)(0x8000000000000000UL)
+#define SHMAT_FLAGS (SHM_RND)
+#else
+#define ADDR (void *)(0x0UL)
+#define SHMAT_FLAGS (0)
+#endif
+
+int main(void)
+{
+ int shmid;
+ unsigned long i;
+ char *shmaddr;
+
+ shmid = shmget(2, LENGTH, SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
+ if (shmid < 0) {
+ perror("shmget");
+ exit(1);
+ }
+ printf("shmid: 0x%x\n", shmid);
+
+ shmaddr = shmat(shmid, ADDR, SHMAT_FLAGS);
+ if (shmaddr == (char *)-1) {
+ perror("Shared memory attach failure");
+ shmctl(shmid, IPC_RMID, NULL);
+ exit(2);
+ }
+ printf("shmaddr: %p\n", shmaddr);
+
+ dprintf("Starting the writes:\n");
+ for (i = 0; i < LENGTH; i++) {
+ shmaddr[i] = (char)(i);
+ if (!(i % (1024 * 1024)))
+ dprintf(".");
+ }
+ dprintf("\n");
+
+ dprintf("Starting the Check...");
+ for (i = 0; i < LENGTH; i++)
+ if (shmaddr[i] != (char)i) {
+ printf("\nIndex %lu mismatched\n", i);
+ exit(3);
+ }
+ dprintf("Done.\n");
+
+ if (shmdt((const void *)shmaddr) != 0) {
+ perror("Detach failure");
+ shmctl(shmid, IPC_RMID, NULL);
+ exit(4);
+ }
+
+ shmctl(shmid, IPC_RMID, NULL);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/hugepage-vmemmap.c b/tools/testing/selftests/mm/hugepage-vmemmap.c
new file mode 100644
index 000000000000..557bdbd4f87e
--- /dev/null
+++ b/tools/testing/selftests/mm/hugepage-vmemmap.c
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * A test case of using hugepage memory in a user application using the
+ * mmap system call with MAP_HUGETLB flag. Before running this program
+ * make sure the administrator has allocated enough default sized huge
+ * pages to cover the 2 MB allocation.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+
+#define MAP_LENGTH (2UL * 1024 * 1024)
+
+#ifndef MAP_HUGETLB
+#define MAP_HUGETLB 0x40000 /* arch specific */
+#endif
+
+#define PAGE_SIZE 4096
+
+#define PAGE_COMPOUND_HEAD (1UL << 15)
+#define PAGE_COMPOUND_TAIL (1UL << 16)
+#define PAGE_HUGE (1UL << 17)
+
+#define HEAD_PAGE_FLAGS (PAGE_COMPOUND_HEAD | PAGE_HUGE)
+#define TAIL_PAGE_FLAGS (PAGE_COMPOUND_TAIL | PAGE_HUGE)
+
+#define PM_PFRAME_BITS 55
+#define PM_PFRAME_MASK ~((1UL << PM_PFRAME_BITS) - 1)
+
+/*
+ * For ia64 architecture, Linux kernel reserves Region number 4 for hugepages.
+ * That means the addresses starting with 0x800000... will need to be
+ * specified. Specifying a fixed address is not required on ppc64, i386
+ * or x86_64.
+ */
+#ifdef __ia64__
+#define MAP_ADDR (void *)(0x8000000000000000UL)
+#define MAP_FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_FIXED)
+#else
+#define MAP_ADDR NULL
+#define MAP_FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB)
+#endif
+
+static void write_bytes(char *addr, size_t length)
+{
+ unsigned long i;
+
+ for (i = 0; i < length; i++)
+ *(addr + i) = (char)i;
+}
+
+static unsigned long virt_to_pfn(void *addr)
+{
+ int fd;
+ unsigned long pagemap;
+
+ fd = open("/proc/self/pagemap", O_RDONLY);
+ if (fd < 0)
+ return -1UL;
+
+ lseek(fd, (unsigned long)addr / PAGE_SIZE * sizeof(pagemap), SEEK_SET);
+ read(fd, &pagemap, sizeof(pagemap));
+ close(fd);
+
+ return pagemap & ~PM_PFRAME_MASK;
+}
+
+static int check_page_flags(unsigned long pfn)
+{
+ int fd, i;
+ unsigned long pageflags;
+
+ fd = open("/proc/kpageflags", O_RDONLY);
+ if (fd < 0)
+ return -1;
+
+ lseek(fd, pfn * sizeof(pageflags), SEEK_SET);
+
+ read(fd, &pageflags, sizeof(pageflags));
+ if ((pageflags & HEAD_PAGE_FLAGS) != HEAD_PAGE_FLAGS) {
+ close(fd);
+ printf("Head page flags (%lx) is invalid\n", pageflags);
+ return -1;
+ }
+
+ /*
+ * pages other than the first page must be tail and shouldn't be head;
+ * this also verifies kernel has correctly set the fake page_head to tail
+ * while hugetlb_free_vmemmap is enabled.
+ */
+ for (i = 1; i < MAP_LENGTH / PAGE_SIZE; i++) {
+ read(fd, &pageflags, sizeof(pageflags));
+ if ((pageflags & TAIL_PAGE_FLAGS) != TAIL_PAGE_FLAGS ||
+ (pageflags & HEAD_PAGE_FLAGS) == HEAD_PAGE_FLAGS) {
+ close(fd);
+ printf("Tail page flags (%lx) is invalid\n", pageflags);
+ return -1;
+ }
+ }
+
+ close(fd);
+
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ void *addr;
+ unsigned long pfn;
+
+ addr = mmap(MAP_ADDR, MAP_LENGTH, PROT_READ | PROT_WRITE, MAP_FLAGS, -1, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+
+ /* Trigger allocation of HugeTLB page. */
+ write_bytes(addr, MAP_LENGTH);
+
+ pfn = virt_to_pfn(addr);
+ if (pfn == -1UL) {
+ munmap(addr, MAP_LENGTH);
+ perror("virt_to_pfn");
+ exit(1);
+ }
+
+ printf("Returned address is %p whose pfn is %lx\n", addr, pfn);
+
+ if (check_page_flags(pfn) < 0) {
+ munmap(addr, MAP_LENGTH);
+ perror("check_page_flags");
+ exit(1);
+ }
+
+ /* munmap() length of MAP_HUGETLB memory must be hugepage aligned */
+ if (munmap(addr, MAP_LENGTH)) {
+ perror("munmap");
+ exit(1);
+ }
+
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/hugetlb-madvise.c b/tools/testing/selftests/mm/hugetlb-madvise.c
new file mode 100644
index 000000000000..9a127a8fe176
--- /dev/null
+++ b/tools/testing/selftests/mm/hugetlb-madvise.c
@@ -0,0 +1,405 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * hugepage-madvise:
+ *
+ * Basic functional testing of madvise MADV_DONTNEED and MADV_REMOVE
+ * on hugetlb mappings.
+ *
+ * Before running this test, make sure the administrator has pre-allocated
+ * at least MIN_FREE_PAGES hugetlb pages and they are free. In addition,
+ * the test takes an argument that is the path to a file in a hugetlbfs
+ * filesystem. Therefore, a hugetlbfs filesystem must be mounted on some
+ * directory.
+ */
+
+#define _GNU_SOURCE
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+
+#define MIN_FREE_PAGES 20
+#define NR_HUGE_PAGES 10 /* common number of pages to map/allocate */
+
+#define validate_free_pages(exp_free) \
+ do { \
+ int fhp = get_free_hugepages(); \
+ if (fhp != (exp_free)) { \
+ printf("Unexpected number of free huge " \
+ "pages line %d\n", __LINE__); \
+ exit(1); \
+ } \
+ } while (0)
+
+unsigned long huge_page_size;
+unsigned long base_page_size;
+
+/*
+ * default_huge_page_size copied from mlock2-tests.c
+ */
+unsigned long default_huge_page_size(void)
+{
+ unsigned long hps = 0;
+ char *line = NULL;
+ size_t linelen = 0;
+ FILE *f = fopen("/proc/meminfo", "r");
+
+ if (!f)
+ return 0;
+ while (getline(&line, &linelen, f) > 0) {
+ if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) {
+ hps <<= 10;
+ break;
+ }
+ }
+
+ free(line);
+ fclose(f);
+ return hps;
+}
+
+unsigned long get_free_hugepages(void)
+{
+ unsigned long fhp = 0;
+ char *line = NULL;
+ size_t linelen = 0;
+ FILE *f = fopen("/proc/meminfo", "r");
+
+ if (!f)
+ return fhp;
+ while (getline(&line, &linelen, f) > 0) {
+ if (sscanf(line, "HugePages_Free: %lu", &fhp) == 1)
+ break;
+ }
+
+ free(line);
+ fclose(f);
+ return fhp;
+}
+
+void write_fault_pages(void *addr, unsigned long nr_pages)
+{
+ unsigned long i;
+
+ for (i = 0; i < nr_pages; i++)
+ *((unsigned long *)(addr + (i * huge_page_size))) = i;
+}
+
+void read_fault_pages(void *addr, unsigned long nr_pages)
+{
+ unsigned long dummy = 0;
+ unsigned long i;
+
+ for (i = 0; i < nr_pages; i++)
+ dummy += *((unsigned long *)(addr + (i * huge_page_size)));
+}
+
+int main(int argc, char **argv)
+{
+ unsigned long free_hugepages;
+ void *addr, *addr2;
+ int fd;
+ int ret;
+
+ huge_page_size = default_huge_page_size();
+ if (!huge_page_size) {
+ printf("Unable to determine huge page size, exiting!\n");
+ exit(1);
+ }
+ base_page_size = sysconf(_SC_PAGE_SIZE);
+ if (!huge_page_size) {
+ printf("Unable to determine base page size, exiting!\n");
+ exit(1);
+ }
+
+ free_hugepages = get_free_hugepages();
+ if (free_hugepages < MIN_FREE_PAGES) {
+ printf("Not enough free huge pages to test, exiting!\n");
+ exit(1);
+ }
+
+ fd = memfd_create(argv[0], MFD_HUGETLB);
+ if (fd < 0) {
+ perror("memfd_create() failed");
+ exit(1);
+ }
+
+ /*
+ * Test validity of MADV_DONTNEED addr and length arguments. mmap
+ * size is NR_HUGE_PAGES + 2. One page at the beginning and end of
+ * the mapping will be unmapped so we KNOW there is nothing mapped
+ * there.
+ */
+ addr = mmap(NULL, (NR_HUGE_PAGES + 2) * huge_page_size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
+ -1, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+ if (munmap(addr, huge_page_size) ||
+ munmap(addr + (NR_HUGE_PAGES + 1) * huge_page_size,
+ huge_page_size)) {
+ perror("munmap");
+ exit(1);
+ }
+ addr = addr + huge_page_size;
+
+ write_fault_pages(addr, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /* addr before mapping should fail */
+ ret = madvise(addr - base_page_size, NR_HUGE_PAGES * huge_page_size,
+ MADV_DONTNEED);
+ if (!ret) {
+ printf("Unexpected success of madvise call with invalid addr line %d\n",
+ __LINE__);
+ exit(1);
+ }
+
+ /* addr + length after mapping should fail */
+ ret = madvise(addr, (NR_HUGE_PAGES * huge_page_size) + base_page_size,
+ MADV_DONTNEED);
+ if (!ret) {
+ printf("Unexpected success of madvise call with invalid length line %d\n",
+ __LINE__);
+ exit(1);
+ }
+
+ (void)munmap(addr, NR_HUGE_PAGES * huge_page_size);
+
+ /*
+ * Test alignment of MADV_DONTNEED addr and length arguments
+ */
+ addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
+ -1, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+ write_fault_pages(addr, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /* addr is not huge page size aligned and should fail */
+ ret = madvise(addr + base_page_size,
+ NR_HUGE_PAGES * huge_page_size - base_page_size,
+ MADV_DONTNEED);
+ if (!ret) {
+ printf("Unexpected success of madvise call with unaligned start address %d\n",
+ __LINE__);
+ exit(1);
+ }
+
+ /* addr + length should be aligned down to huge page size */
+ if (madvise(addr,
+ ((NR_HUGE_PAGES - 1) * huge_page_size) + base_page_size,
+ MADV_DONTNEED)) {
+ perror("madvise");
+ exit(1);
+ }
+
+ /* should free all but last page in mapping */
+ validate_free_pages(free_hugepages - 1);
+
+ (void)munmap(addr, NR_HUGE_PAGES * huge_page_size);
+ validate_free_pages(free_hugepages);
+
+ /*
+ * Test MADV_DONTNEED on anonymous private mapping
+ */
+ addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB,
+ -1, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+ write_fault_pages(addr, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) {
+ perror("madvise");
+ exit(1);
+ }
+
+ /* should free all pages in mapping */
+ validate_free_pages(free_hugepages);
+
+ (void)munmap(addr, NR_HUGE_PAGES * huge_page_size);
+
+ /*
+ * Test MADV_DONTNEED on private mapping of hugetlb file
+ */
+ if (fallocate(fd, 0, 0, NR_HUGE_PAGES * huge_page_size)) {
+ perror("fallocate");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE, fd, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+
+ /* read should not consume any pages */
+ read_fault_pages(addr, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /* madvise should not free any pages */
+ if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) {
+ perror("madvise");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /* writes should allocate private pages */
+ write_fault_pages(addr, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES));
+
+ /* madvise should free private pages */
+ if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) {
+ perror("madvise");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /* writes should allocate private pages */
+ write_fault_pages(addr, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES));
+
+ /*
+ * The fallocate below certainly should free the pages associated
+ * with the file. However, pages in the private mapping are also
+ * freed. This is not the 'correct' behavior, but is expected
+ * because this is how it has worked since the initial hugetlb
+ * implementation.
+ */
+ if (fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ 0, NR_HUGE_PAGES * huge_page_size)) {
+ perror("fallocate");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages);
+
+ (void)munmap(addr, NR_HUGE_PAGES * huge_page_size);
+
+ /*
+ * Test MADV_DONTNEED on shared mapping of hugetlb file
+ */
+ if (fallocate(fd, 0, 0, NR_HUGE_PAGES * huge_page_size)) {
+ perror("fallocate");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+
+ /* write should not consume any pages */
+ write_fault_pages(addr, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /* madvise should not free any pages */
+ if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) {
+ perror("madvise");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /*
+ * Test MADV_REMOVE on shared mapping of hugetlb file
+ *
+ * madvise is same as hole punch and should free all pages.
+ */
+ if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_REMOVE)) {
+ perror("madvise");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages);
+ (void)munmap(addr, NR_HUGE_PAGES * huge_page_size);
+
+ /*
+ * Test MADV_REMOVE on shared and private mapping of hugetlb file
+ */
+ if (fallocate(fd, 0, 0, NR_HUGE_PAGES * huge_page_size)) {
+ perror("fallocate");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ addr = mmap(NULL, NR_HUGE_PAGES * huge_page_size,
+ PROT_READ | PROT_WRITE,
+ MAP_SHARED, fd, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+
+ /* shared write should not consume any additional pages */
+ write_fault_pages(addr, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ addr2 = mmap(NULL, NR_HUGE_PAGES * huge_page_size,
+ PROT_READ | PROT_WRITE,
+ MAP_PRIVATE, fd, 0);
+ if (addr2 == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+
+ /* private read should not consume any pages */
+ read_fault_pages(addr2, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /* private write should consume additional pages */
+ write_fault_pages(addr2, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES));
+
+ /* madvise of shared mapping should not free any pages */
+ if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) {
+ perror("madvise");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES));
+
+ /* madvise of private mapping should free private pages */
+ if (madvise(addr2, NR_HUGE_PAGES * huge_page_size, MADV_DONTNEED)) {
+ perror("madvise");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages - NR_HUGE_PAGES);
+
+ /* private write should consume additional pages again */
+ write_fault_pages(addr2, NR_HUGE_PAGES);
+ validate_free_pages(free_hugepages - (2 * NR_HUGE_PAGES));
+
+ /*
+ * madvise should free both file and private pages although this is
+ * not correct. private pages should not be freed, but this is
+ * expected. See comment associated with FALLOC_FL_PUNCH_HOLE call.
+ */
+ if (madvise(addr, NR_HUGE_PAGES * huge_page_size, MADV_REMOVE)) {
+ perror("madvise");
+ exit(1);
+ }
+ validate_free_pages(free_hugepages);
+
+ (void)munmap(addr, NR_HUGE_PAGES * huge_page_size);
+ (void)munmap(addr2, NR_HUGE_PAGES * huge_page_size);
+
+ close(fd);
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/hugetlb_reparenting_test.sh b/tools/testing/selftests/mm/hugetlb_reparenting_test.sh
new file mode 100644
index 000000000000..bf2d2a684edf
--- /dev/null
+++ b/tools/testing/selftests/mm/hugetlb_reparenting_test.sh
@@ -0,0 +1,252 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+set -e
+
+if [[ $(id -u) -ne 0 ]]; then
+ echo "This test must be run as root. Skipping..."
+ exit $ksft_skip
+fi
+
+usage_file=usage_in_bytes
+
+if [[ "$1" == "-cgroup-v2" ]]; then
+ cgroup2=1
+ usage_file=current
+fi
+
+
+if [[ $cgroup2 ]]; then
+ CGROUP_ROOT=$(mount -t cgroup2 | head -1 | awk -e '{print $3}')
+ if [[ -z "$CGROUP_ROOT" ]]; then
+ CGROUP_ROOT=/dev/cgroup/memory
+ mount -t cgroup2 none $CGROUP_ROOT
+ do_umount=1
+ fi
+ echo "+hugetlb +memory" >$CGROUP_ROOT/cgroup.subtree_control
+else
+ CGROUP_ROOT=$(mount -t cgroup | grep ",hugetlb" | awk -e '{print $3}')
+ if [[ -z "$CGROUP_ROOT" ]]; then
+ CGROUP_ROOT=/dev/cgroup/memory
+ mount -t cgroup memory,hugetlb $CGROUP_ROOT
+ do_umount=1
+ fi
+fi
+MNT='/mnt/huge/'
+
+function get_machine_hugepage_size() {
+ hpz=$(grep -i hugepagesize /proc/meminfo)
+ kb=${hpz:14:-3}
+ mb=$(($kb / 1024))
+ echo $mb
+}
+
+MB=$(get_machine_hugepage_size)
+
+function cleanup() {
+ echo cleanup
+ set +e
+ rm -rf "$MNT"/* 2>/dev/null
+ umount "$MNT" 2>/dev/null
+ rmdir "$MNT" 2>/dev/null
+ rmdir "$CGROUP_ROOT"/a/b 2>/dev/null
+ rmdir "$CGROUP_ROOT"/a 2>/dev/null
+ rmdir "$CGROUP_ROOT"/test1 2>/dev/null
+ echo 0 >/proc/sys/vm/nr_hugepages
+ set -e
+}
+
+function assert_state() {
+ local expected_a="$1"
+ local expected_a_hugetlb="$2"
+ local expected_b=""
+ local expected_b_hugetlb=""
+
+ if [ ! -z ${3:-} ] && [ ! -z ${4:-} ]; then
+ expected_b="$3"
+ expected_b_hugetlb="$4"
+ fi
+ local tolerance=$((5 * 1024 * 1024))
+
+ local actual_a
+ actual_a="$(cat "$CGROUP_ROOT"/a/memory.$usage_file)"
+ if [[ $actual_a -lt $(($expected_a - $tolerance)) ]] ||
+ [[ $actual_a -gt $(($expected_a + $tolerance)) ]]; then
+ echo actual a = $((${actual_a%% *} / 1024 / 1024)) MB
+ echo expected a = $((${expected_a%% *} / 1024 / 1024)) MB
+ echo fail
+
+ cleanup
+ exit 1
+ fi
+
+ local actual_a_hugetlb
+ actual_a_hugetlb="$(cat "$CGROUP_ROOT"/a/hugetlb.${MB}MB.$usage_file)"
+ if [[ $actual_a_hugetlb -lt $(($expected_a_hugetlb - $tolerance)) ]] ||
+ [[ $actual_a_hugetlb -gt $(($expected_a_hugetlb + $tolerance)) ]]; then
+ echo actual a hugetlb = $((${actual_a_hugetlb%% *} / 1024 / 1024)) MB
+ echo expected a hugetlb = $((${expected_a_hugetlb%% *} / 1024 / 1024)) MB
+ echo fail
+
+ cleanup
+ exit 1
+ fi
+
+ if [[ -z "$expected_b" || -z "$expected_b_hugetlb" ]]; then
+ return
+ fi
+
+ local actual_b
+ actual_b="$(cat "$CGROUP_ROOT"/a/b/memory.$usage_file)"
+ if [[ $actual_b -lt $(($expected_b - $tolerance)) ]] ||
+ [[ $actual_b -gt $(($expected_b + $tolerance)) ]]; then
+ echo actual b = $((${actual_b%% *} / 1024 / 1024)) MB
+ echo expected b = $((${expected_b%% *} / 1024 / 1024)) MB
+ echo fail
+
+ cleanup
+ exit 1
+ fi
+
+ local actual_b_hugetlb
+ actual_b_hugetlb="$(cat "$CGROUP_ROOT"/a/b/hugetlb.${MB}MB.$usage_file)"
+ if [[ $actual_b_hugetlb -lt $(($expected_b_hugetlb - $tolerance)) ]] ||
+ [[ $actual_b_hugetlb -gt $(($expected_b_hugetlb + $tolerance)) ]]; then
+ echo actual b hugetlb = $((${actual_b_hugetlb%% *} / 1024 / 1024)) MB
+ echo expected b hugetlb = $((${expected_b_hugetlb%% *} / 1024 / 1024)) MB
+ echo fail
+
+ cleanup
+ exit 1
+ fi
+}
+
+function setup() {
+ echo 100 >/proc/sys/vm/nr_hugepages
+ mkdir "$CGROUP_ROOT"/a
+ sleep 1
+ if [[ $cgroup2 ]]; then
+ echo "+hugetlb +memory" >$CGROUP_ROOT/a/cgroup.subtree_control
+ else
+ echo 0 >$CGROUP_ROOT/a/cpuset.mems
+ echo 0 >$CGROUP_ROOT/a/cpuset.cpus
+ fi
+
+ mkdir "$CGROUP_ROOT"/a/b
+
+ if [[ ! $cgroup2 ]]; then
+ echo 0 >$CGROUP_ROOT/a/b/cpuset.mems
+ echo 0 >$CGROUP_ROOT/a/b/cpuset.cpus
+ fi
+
+ mkdir -p "$MNT"
+ mount -t hugetlbfs none "$MNT"
+}
+
+write_hugetlbfs() {
+ local cgroup="$1"
+ local path="$2"
+ local size="$3"
+
+ if [[ $cgroup2 ]]; then
+ echo $$ >$CGROUP_ROOT/$cgroup/cgroup.procs
+ else
+ echo 0 >$CGROUP_ROOT/$cgroup/cpuset.mems
+ echo 0 >$CGROUP_ROOT/$cgroup/cpuset.cpus
+ echo $$ >"$CGROUP_ROOT/$cgroup/tasks"
+ fi
+ ./write_to_hugetlbfs -p "$path" -s "$size" -m 0 -o
+ if [[ $cgroup2 ]]; then
+ echo $$ >$CGROUP_ROOT/cgroup.procs
+ else
+ echo $$ >"$CGROUP_ROOT/tasks"
+ fi
+ echo
+}
+
+set -e
+
+size=$((${MB} * 1024 * 1024 * 25)) # 50MB = 25 * 2MB hugepages.
+
+cleanup
+
+echo
+echo
+echo Test charge, rmdir, uncharge
+setup
+echo mkdir
+mkdir $CGROUP_ROOT/test1
+
+echo write
+write_hugetlbfs test1 "$MNT"/test $size
+
+echo rmdir
+rmdir $CGROUP_ROOT/test1
+mkdir $CGROUP_ROOT/test1
+
+echo uncharge
+rm -rf /mnt/huge/*
+
+cleanup
+
+echo done
+echo
+echo
+if [[ ! $cgroup2 ]]; then
+ echo "Test parent and child hugetlb usage"
+ setup
+
+ echo write
+ write_hugetlbfs a "$MNT"/test $size
+
+ echo Assert memory charged correctly for parent use.
+ assert_state 0 $size 0 0
+
+ write_hugetlbfs a/b "$MNT"/test2 $size
+
+ echo Assert memory charged correctly for child use.
+ assert_state 0 $(($size * 2)) 0 $size
+
+ rmdir "$CGROUP_ROOT"/a/b
+ sleep 5
+ echo Assert memory reparent correctly.
+ assert_state 0 $(($size * 2))
+
+ rm -rf "$MNT"/*
+ umount "$MNT"
+ echo Assert memory uncharged correctly.
+ assert_state 0 0
+
+ cleanup
+fi
+
+echo
+echo
+echo "Test child only hugetlb usage"
+echo setup
+setup
+
+echo write
+write_hugetlbfs a/b "$MNT"/test2 $size
+
+echo Assert memory charged correctly for child only use.
+assert_state 0 $(($size)) 0 $size
+
+rmdir "$CGROUP_ROOT"/a/b
+echo Assert memory reparent correctly.
+assert_state 0 $size
+
+rm -rf "$MNT"/*
+umount "$MNT"
+echo Assert memory uncharged correctly.
+assert_state 0 0
+
+cleanup
+
+echo ALL PASS
+
+umount $CGROUP_ROOT
+rm -rf $CGROUP_ROOT
diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c
new file mode 100644
index 000000000000..64126c8cd561
--- /dev/null
+++ b/tools/testing/selftests/mm/khugepaged.c
@@ -0,0 +1,1558 @@
+#define _GNU_SOURCE
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <dirent.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/sysmacros.h>
+#include <sys/vfs.h>
+
+#include "linux/magic.h"
+
+#include "vm_util.h"
+
+#ifndef MADV_PAGEOUT
+#define MADV_PAGEOUT 21
+#endif
+#ifndef MADV_POPULATE_READ
+#define MADV_POPULATE_READ 22
+#endif
+#ifndef MADV_COLLAPSE
+#define MADV_COLLAPSE 25
+#endif
+
+#define BASE_ADDR ((void *)(1UL << 30))
+static unsigned long hpage_pmd_size;
+static unsigned long page_size;
+static int hpage_pmd_nr;
+
+#define THP_SYSFS "/sys/kernel/mm/transparent_hugepage/"
+#define PID_SMAPS "/proc/self/smaps"
+#define TEST_FILE "collapse_test_file"
+
+#define MAX_LINE_LENGTH 500
+
+enum vma_type {
+ VMA_ANON,
+ VMA_FILE,
+ VMA_SHMEM,
+};
+
+struct mem_ops {
+ void *(*setup_area)(int nr_hpages);
+ void (*cleanup_area)(void *p, unsigned long size);
+ void (*fault)(void *p, unsigned long start, unsigned long end);
+ bool (*check_huge)(void *addr, int nr_hpages);
+ const char *name;
+};
+
+static struct mem_ops *file_ops;
+static struct mem_ops *anon_ops;
+static struct mem_ops *shmem_ops;
+
+struct collapse_context {
+ void (*collapse)(const char *msg, char *p, int nr_hpages,
+ struct mem_ops *ops, bool expect);
+ bool enforce_pte_scan_limits;
+ const char *name;
+};
+
+static struct collapse_context *khugepaged_context;
+static struct collapse_context *madvise_context;
+
+struct file_info {
+ const char *dir;
+ char path[PATH_MAX];
+ enum vma_type type;
+ int fd;
+ char dev_queue_read_ahead_path[PATH_MAX];
+};
+
+static struct file_info finfo;
+
+enum thp_enabled {
+ THP_ALWAYS,
+ THP_MADVISE,
+ THP_NEVER,
+};
+
+static const char *thp_enabled_strings[] = {
+ "always",
+ "madvise",
+ "never",
+ NULL
+};
+
+enum thp_defrag {
+ THP_DEFRAG_ALWAYS,
+ THP_DEFRAG_DEFER,
+ THP_DEFRAG_DEFER_MADVISE,
+ THP_DEFRAG_MADVISE,
+ THP_DEFRAG_NEVER,
+};
+
+static const char *thp_defrag_strings[] = {
+ "always",
+ "defer",
+ "defer+madvise",
+ "madvise",
+ "never",
+ NULL
+};
+
+enum shmem_enabled {
+ SHMEM_ALWAYS,
+ SHMEM_WITHIN_SIZE,
+ SHMEM_ADVISE,
+ SHMEM_NEVER,
+ SHMEM_DENY,
+ SHMEM_FORCE,
+};
+
+static const char *shmem_enabled_strings[] = {
+ "always",
+ "within_size",
+ "advise",
+ "never",
+ "deny",
+ "force",
+ NULL
+};
+
+struct khugepaged_settings {
+ bool defrag;
+ unsigned int alloc_sleep_millisecs;
+ unsigned int scan_sleep_millisecs;
+ unsigned int max_ptes_none;
+ unsigned int max_ptes_swap;
+ unsigned int max_ptes_shared;
+ unsigned long pages_to_scan;
+};
+
+struct settings {
+ enum thp_enabled thp_enabled;
+ enum thp_defrag thp_defrag;
+ enum shmem_enabled shmem_enabled;
+ bool use_zero_page;
+ struct khugepaged_settings khugepaged;
+ unsigned long read_ahead_kb;
+};
+
+static struct settings saved_settings;
+static bool skip_settings_restore;
+
+static int exit_status;
+
+static void success(const char *msg)
+{
+ printf(" \e[32m%s\e[0m\n", msg);
+}
+
+static void fail(const char *msg)
+{
+ printf(" \e[31m%s\e[0m\n", msg);
+ exit_status++;
+}
+
+static void skip(const char *msg)
+{
+ printf(" \e[33m%s\e[0m\n", msg);
+}
+
+static int read_file(const char *path, char *buf, size_t buflen)
+{
+ int fd;
+ ssize_t numread;
+
+ fd = open(path, O_RDONLY);
+ if (fd == -1)
+ return 0;
+
+ numread = read(fd, buf, buflen - 1);
+ if (numread < 1) {
+ close(fd);
+ return 0;
+ }
+
+ buf[numread] = '\0';
+ close(fd);
+
+ return (unsigned int) numread;
+}
+
+static int write_file(const char *path, const char *buf, size_t buflen)
+{
+ int fd;
+ ssize_t numwritten;
+
+ fd = open(path, O_WRONLY);
+ if (fd == -1) {
+ printf("open(%s)\n", path);
+ exit(EXIT_FAILURE);
+ return 0;
+ }
+
+ numwritten = write(fd, buf, buflen - 1);
+ close(fd);
+ if (numwritten < 1) {
+ printf("write(%s)\n", buf);
+ exit(EXIT_FAILURE);
+ return 0;
+ }
+
+ return (unsigned int) numwritten;
+}
+
+static int read_string(const char *name, const char *strings[])
+{
+ char path[PATH_MAX];
+ char buf[256];
+ char *c;
+ int ret;
+
+ ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
+ if (ret >= PATH_MAX) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+
+ if (!read_file(path, buf, sizeof(buf))) {
+ perror(path);
+ exit(EXIT_FAILURE);
+ }
+
+ c = strchr(buf, '[');
+ if (!c) {
+ printf("%s: Parse failure\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+
+ c++;
+ memmove(buf, c, sizeof(buf) - (c - buf));
+
+ c = strchr(buf, ']');
+ if (!c) {
+ printf("%s: Parse failure\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+ *c = '\0';
+
+ ret = 0;
+ while (strings[ret]) {
+ if (!strcmp(strings[ret], buf))
+ return ret;
+ ret++;
+ }
+
+ printf("Failed to parse %s\n", name);
+ exit(EXIT_FAILURE);
+}
+
+static void write_string(const char *name, const char *val)
+{
+ char path[PATH_MAX];
+ int ret;
+
+ ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
+ if (ret >= PATH_MAX) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+
+ if (!write_file(path, val, strlen(val) + 1)) {
+ perror(path);
+ exit(EXIT_FAILURE);
+ }
+}
+
+static const unsigned long _read_num(const char *path)
+{
+ char buf[21];
+
+ if (read_file(path, buf, sizeof(buf)) < 0) {
+ perror("read_file(read_num)");
+ exit(EXIT_FAILURE);
+ }
+
+ return strtoul(buf, NULL, 10);
+}
+
+static const unsigned long read_num(const char *name)
+{
+ char path[PATH_MAX];
+ int ret;
+
+ ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
+ if (ret >= PATH_MAX) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+ return _read_num(path);
+}
+
+static void _write_num(const char *path, unsigned long num)
+{
+ char buf[21];
+
+ sprintf(buf, "%ld", num);
+ if (!write_file(path, buf, strlen(buf) + 1)) {
+ perror(path);
+ exit(EXIT_FAILURE);
+ }
+}
+
+static void write_num(const char *name, unsigned long num)
+{
+ char path[PATH_MAX];
+ int ret;
+
+ ret = snprintf(path, PATH_MAX, THP_SYSFS "%s", name);
+ if (ret >= PATH_MAX) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+ _write_num(path, num);
+}
+
+static void write_settings(struct settings *settings)
+{
+ struct khugepaged_settings *khugepaged = &settings->khugepaged;
+
+ write_string("enabled", thp_enabled_strings[settings->thp_enabled]);
+ write_string("defrag", thp_defrag_strings[settings->thp_defrag]);
+ write_string("shmem_enabled",
+ shmem_enabled_strings[settings->shmem_enabled]);
+ write_num("use_zero_page", settings->use_zero_page);
+
+ write_num("khugepaged/defrag", khugepaged->defrag);
+ write_num("khugepaged/alloc_sleep_millisecs",
+ khugepaged->alloc_sleep_millisecs);
+ write_num("khugepaged/scan_sleep_millisecs",
+ khugepaged->scan_sleep_millisecs);
+ write_num("khugepaged/max_ptes_none", khugepaged->max_ptes_none);
+ write_num("khugepaged/max_ptes_swap", khugepaged->max_ptes_swap);
+ write_num("khugepaged/max_ptes_shared", khugepaged->max_ptes_shared);
+ write_num("khugepaged/pages_to_scan", khugepaged->pages_to_scan);
+
+ if (file_ops && finfo.type == VMA_FILE)
+ _write_num(finfo.dev_queue_read_ahead_path,
+ settings->read_ahead_kb);
+}
+
+#define MAX_SETTINGS_DEPTH 4
+static struct settings settings_stack[MAX_SETTINGS_DEPTH];
+static int settings_index;
+
+static struct settings *current_settings(void)
+{
+ if (!settings_index) {
+ printf("Fail: No settings set");
+ exit(EXIT_FAILURE);
+ }
+ return settings_stack + settings_index - 1;
+}
+
+static void push_settings(struct settings *settings)
+{
+ if (settings_index >= MAX_SETTINGS_DEPTH) {
+ printf("Fail: Settings stack exceeded");
+ exit(EXIT_FAILURE);
+ }
+ settings_stack[settings_index++] = *settings;
+ write_settings(current_settings());
+}
+
+static void pop_settings(void)
+{
+ if (settings_index <= 0) {
+ printf("Fail: Settings stack empty");
+ exit(EXIT_FAILURE);
+ }
+ --settings_index;
+ write_settings(current_settings());
+}
+
+static void restore_settings(int sig)
+{
+ if (skip_settings_restore)
+ goto out;
+
+ printf("Restore THP and khugepaged settings...");
+ write_settings(&saved_settings);
+ success("OK");
+ if (sig)
+ exit(EXIT_FAILURE);
+out:
+ exit(exit_status);
+}
+
+static void save_settings(void)
+{
+ printf("Save THP and khugepaged settings...");
+ saved_settings = (struct settings) {
+ .thp_enabled = read_string("enabled", thp_enabled_strings),
+ .thp_defrag = read_string("defrag", thp_defrag_strings),
+ .shmem_enabled =
+ read_string("shmem_enabled", shmem_enabled_strings),
+ .use_zero_page = read_num("use_zero_page"),
+ };
+ saved_settings.khugepaged = (struct khugepaged_settings) {
+ .defrag = read_num("khugepaged/defrag"),
+ .alloc_sleep_millisecs =
+ read_num("khugepaged/alloc_sleep_millisecs"),
+ .scan_sleep_millisecs =
+ read_num("khugepaged/scan_sleep_millisecs"),
+ .max_ptes_none = read_num("khugepaged/max_ptes_none"),
+ .max_ptes_swap = read_num("khugepaged/max_ptes_swap"),
+ .max_ptes_shared = read_num("khugepaged/max_ptes_shared"),
+ .pages_to_scan = read_num("khugepaged/pages_to_scan"),
+ };
+ if (file_ops && finfo.type == VMA_FILE)
+ saved_settings.read_ahead_kb =
+ _read_num(finfo.dev_queue_read_ahead_path);
+
+ success("OK");
+
+ signal(SIGTERM, restore_settings);
+ signal(SIGINT, restore_settings);
+ signal(SIGHUP, restore_settings);
+ signal(SIGQUIT, restore_settings);
+}
+
+static void get_finfo(const char *dir)
+{
+ struct stat path_stat;
+ struct statfs fs;
+ char buf[1 << 10];
+ char path[PATH_MAX];
+ char *str, *end;
+
+ finfo.dir = dir;
+ stat(finfo.dir, &path_stat);
+ if (!S_ISDIR(path_stat.st_mode)) {
+ printf("%s: Not a directory (%s)\n", __func__, finfo.dir);
+ exit(EXIT_FAILURE);
+ }
+ if (snprintf(finfo.path, sizeof(finfo.path), "%s/" TEST_FILE,
+ finfo.dir) >= sizeof(finfo.path)) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+ if (statfs(finfo.dir, &fs)) {
+ perror("statfs()");
+ exit(EXIT_FAILURE);
+ }
+ finfo.type = fs.f_type == TMPFS_MAGIC ? VMA_SHMEM : VMA_FILE;
+ if (finfo.type == VMA_SHMEM)
+ return;
+
+ /* Find owning device's queue/read_ahead_kb control */
+ if (snprintf(path, sizeof(path), "/sys/dev/block/%d:%d/uevent",
+ major(path_stat.st_dev), minor(path_stat.st_dev))
+ >= sizeof(path)) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+ if (read_file(path, buf, sizeof(buf)) < 0) {
+ perror("read_file(read_num)");
+ exit(EXIT_FAILURE);
+ }
+ if (strstr(buf, "DEVTYPE=disk")) {
+ /* Found it */
+ if (snprintf(finfo.dev_queue_read_ahead_path,
+ sizeof(finfo.dev_queue_read_ahead_path),
+ "/sys/dev/block/%d:%d/queue/read_ahead_kb",
+ major(path_stat.st_dev), minor(path_stat.st_dev))
+ >= sizeof(finfo.dev_queue_read_ahead_path)) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+ return;
+ }
+ if (!strstr(buf, "DEVTYPE=partition")) {
+ printf("%s: Unknown device type: %s\n", __func__, path);
+ exit(EXIT_FAILURE);
+ }
+ /*
+ * Partition of block device - need to find actual device.
+ * Using naming convention that devnameN is partition of
+ * device devname.
+ */
+ str = strstr(buf, "DEVNAME=");
+ if (!str) {
+ printf("%s: Could not read: %s", __func__, path);
+ exit(EXIT_FAILURE);
+ }
+ str += 8;
+ end = str;
+ while (*end) {
+ if (isdigit(*end)) {
+ *end = '\0';
+ if (snprintf(finfo.dev_queue_read_ahead_path,
+ sizeof(finfo.dev_queue_read_ahead_path),
+ "/sys/block/%s/queue/read_ahead_kb",
+ str) >= sizeof(finfo.dev_queue_read_ahead_path)) {
+ printf("%s: Pathname is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+ return;
+ }
+ ++end;
+ }
+ printf("%s: Could not read: %s\n", __func__, path);
+ exit(EXIT_FAILURE);
+}
+
+static bool check_swap(void *addr, unsigned long size)
+{
+ bool swap = false;
+ int ret;
+ FILE *fp;
+ char buffer[MAX_LINE_LENGTH];
+ char addr_pattern[MAX_LINE_LENGTH];
+
+ ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-",
+ (unsigned long) addr);
+ if (ret >= MAX_LINE_LENGTH) {
+ printf("%s: Pattern is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+
+
+ fp = fopen(PID_SMAPS, "r");
+ if (!fp) {
+ printf("%s: Failed to open file %s\n", __func__, PID_SMAPS);
+ exit(EXIT_FAILURE);
+ }
+ if (!check_for_pattern(fp, addr_pattern, buffer, sizeof(buffer)))
+ goto err_out;
+
+ ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "Swap:%19ld kB",
+ size >> 10);
+ if (ret >= MAX_LINE_LENGTH) {
+ printf("%s: Pattern is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+ /*
+ * Fetch the Swap: in the same block and check whether it got
+ * the expected number of hugeepages next.
+ */
+ if (!check_for_pattern(fp, "Swap:", buffer, sizeof(buffer)))
+ goto err_out;
+
+ if (strncmp(buffer, addr_pattern, strlen(addr_pattern)))
+ goto err_out;
+
+ swap = true;
+err_out:
+ fclose(fp);
+ return swap;
+}
+
+static void *alloc_mapping(int nr)
+{
+ void *p;
+
+ p = mmap(BASE_ADDR, nr * hpage_pmd_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ if (p != BASE_ADDR) {
+ printf("Failed to allocate VMA at %p\n", BASE_ADDR);
+ exit(EXIT_FAILURE);
+ }
+
+ return p;
+}
+
+static void fill_memory(int *p, unsigned long start, unsigned long end)
+{
+ int i;
+
+ for (i = start / page_size; i < end / page_size; i++)
+ p[i * page_size / sizeof(*p)] = i + 0xdead0000;
+}
+
+/*
+ * MADV_COLLAPSE is a best-effort request and may fail if an internal
+ * resource is temporarily unavailable, in which case it will set errno to
+ * EAGAIN. In such a case, immediately reattempt the operation one more
+ * time.
+ */
+static int madvise_collapse_retry(void *p, unsigned long size)
+{
+ bool retry = true;
+ int ret;
+
+retry:
+ ret = madvise(p, size, MADV_COLLAPSE);
+ if (ret && errno == EAGAIN && retry) {
+ retry = false;
+ goto retry;
+ }
+ return ret;
+}
+
+/*
+ * Returns pmd-mapped hugepage in VMA marked VM_HUGEPAGE, filled with
+ * validate_memory()'able contents.
+ */
+static void *alloc_hpage(struct mem_ops *ops)
+{
+ void *p = ops->setup_area(1);
+
+ ops->fault(p, 0, hpage_pmd_size);
+
+ /*
+ * VMA should be neither VM_HUGEPAGE nor VM_NOHUGEPAGE.
+ * The latter is ineligible for collapse by MADV_COLLAPSE
+ * while the former might cause MADV_COLLAPSE to race with
+ * khugepaged on low-load system (like a test machine), which
+ * would cause MADV_COLLAPSE to fail with EAGAIN.
+ */
+ printf("Allocate huge page...");
+ if (madvise_collapse_retry(p, hpage_pmd_size)) {
+ perror("madvise(MADV_COLLAPSE)");
+ exit(EXIT_FAILURE);
+ }
+ if (!ops->check_huge(p, 1)) {
+ perror("madvise(MADV_COLLAPSE)");
+ exit(EXIT_FAILURE);
+ }
+ if (madvise(p, hpage_pmd_size, MADV_HUGEPAGE)) {
+ perror("madvise(MADV_HUGEPAGE)");
+ exit(EXIT_FAILURE);
+ }
+ success("OK");
+ return p;
+}
+
+static void validate_memory(int *p, unsigned long start, unsigned long end)
+{
+ int i;
+
+ for (i = start / page_size; i < end / page_size; i++) {
+ if (p[i * page_size / sizeof(*p)] != i + 0xdead0000) {
+ printf("Page %d is corrupted: %#x\n",
+ i, p[i * page_size / sizeof(*p)]);
+ exit(EXIT_FAILURE);
+ }
+ }
+}
+
+static void *anon_setup_area(int nr_hpages)
+{
+ return alloc_mapping(nr_hpages);
+}
+
+static void anon_cleanup_area(void *p, unsigned long size)
+{
+ munmap(p, size);
+}
+
+static void anon_fault(void *p, unsigned long start, unsigned long end)
+{
+ fill_memory(p, start, end);
+}
+
+static bool anon_check_huge(void *addr, int nr_hpages)
+{
+ return check_huge_anon(addr, nr_hpages, hpage_pmd_size);
+}
+
+static void *file_setup_area(int nr_hpages)
+{
+ int fd;
+ void *p;
+ unsigned long size;
+
+ unlink(finfo.path); /* Cleanup from previous failed tests */
+ printf("Creating %s for collapse%s...", finfo.path,
+ finfo.type == VMA_SHMEM ? " (tmpfs)" : "");
+ fd = open(finfo.path, O_DSYNC | O_CREAT | O_RDWR | O_TRUNC | O_EXCL,
+ 777);
+ if (fd < 0) {
+ perror("open()");
+ exit(EXIT_FAILURE);
+ }
+
+ size = nr_hpages * hpage_pmd_size;
+ p = alloc_mapping(nr_hpages);
+ fill_memory(p, 0, size);
+ write(fd, p, size);
+ close(fd);
+ munmap(p, size);
+ success("OK");
+
+ printf("Opening %s read only for collapse...", finfo.path);
+ finfo.fd = open(finfo.path, O_RDONLY, 777);
+ if (finfo.fd < 0) {
+ perror("open()");
+ exit(EXIT_FAILURE);
+ }
+ p = mmap(BASE_ADDR, size, PROT_READ | PROT_EXEC,
+ MAP_PRIVATE, finfo.fd, 0);
+ if (p == MAP_FAILED || p != BASE_ADDR) {
+ perror("mmap()");
+ exit(EXIT_FAILURE);
+ }
+
+ /* Drop page cache */
+ write_file("/proc/sys/vm/drop_caches", "3", 2);
+ success("OK");
+ return p;
+}
+
+static void file_cleanup_area(void *p, unsigned long size)
+{
+ munmap(p, size);
+ close(finfo.fd);
+ unlink(finfo.path);
+}
+
+static void file_fault(void *p, unsigned long start, unsigned long end)
+{
+ if (madvise(((char *)p) + start, end - start, MADV_POPULATE_READ)) {
+ perror("madvise(MADV_POPULATE_READ");
+ exit(EXIT_FAILURE);
+ }
+}
+
+static bool file_check_huge(void *addr, int nr_hpages)
+{
+ switch (finfo.type) {
+ case VMA_FILE:
+ return check_huge_file(addr, nr_hpages, hpage_pmd_size);
+ case VMA_SHMEM:
+ return check_huge_shmem(addr, nr_hpages, hpage_pmd_size);
+ default:
+ exit(EXIT_FAILURE);
+ return false;
+ }
+}
+
+static void *shmem_setup_area(int nr_hpages)
+{
+ void *p;
+ unsigned long size = nr_hpages * hpage_pmd_size;
+
+ finfo.fd = memfd_create("khugepaged-selftest-collapse-shmem", 0);
+ if (finfo.fd < 0) {
+ perror("memfd_create()");
+ exit(EXIT_FAILURE);
+ }
+ if (ftruncate(finfo.fd, size)) {
+ perror("ftruncate()");
+ exit(EXIT_FAILURE);
+ }
+ p = mmap(BASE_ADDR, size, PROT_READ | PROT_WRITE, MAP_SHARED, finfo.fd,
+ 0);
+ if (p != BASE_ADDR) {
+ perror("mmap()");
+ exit(EXIT_FAILURE);
+ }
+ return p;
+}
+
+static void shmem_cleanup_area(void *p, unsigned long size)
+{
+ munmap(p, size);
+ close(finfo.fd);
+}
+
+static bool shmem_check_huge(void *addr, int nr_hpages)
+{
+ return check_huge_shmem(addr, nr_hpages, hpage_pmd_size);
+}
+
+static struct mem_ops __anon_ops = {
+ .setup_area = &anon_setup_area,
+ .cleanup_area = &anon_cleanup_area,
+ .fault = &anon_fault,
+ .check_huge = &anon_check_huge,
+ .name = "anon",
+};
+
+static struct mem_ops __file_ops = {
+ .setup_area = &file_setup_area,
+ .cleanup_area = &file_cleanup_area,
+ .fault = &file_fault,
+ .check_huge = &file_check_huge,
+ .name = "file",
+};
+
+static struct mem_ops __shmem_ops = {
+ .setup_area = &shmem_setup_area,
+ .cleanup_area = &shmem_cleanup_area,
+ .fault = &anon_fault,
+ .check_huge = &shmem_check_huge,
+ .name = "shmem",
+};
+
+static void __madvise_collapse(const char *msg, char *p, int nr_hpages,
+ struct mem_ops *ops, bool expect)
+{
+ int ret;
+ struct settings settings = *current_settings();
+
+ printf("%s...", msg);
+
+ /*
+ * Prevent khugepaged interference and tests that MADV_COLLAPSE
+ * ignores /sys/kernel/mm/transparent_hugepage/enabled
+ */
+ settings.thp_enabled = THP_NEVER;
+ settings.shmem_enabled = SHMEM_NEVER;
+ push_settings(&settings);
+
+ /* Clear VM_NOHUGEPAGE */
+ madvise(p, nr_hpages * hpage_pmd_size, MADV_HUGEPAGE);
+ ret = madvise_collapse_retry(p, nr_hpages * hpage_pmd_size);
+ if (((bool)ret) == expect)
+ fail("Fail: Bad return value");
+ else if (!ops->check_huge(p, expect ? nr_hpages : 0))
+ fail("Fail: check_huge()");
+ else
+ success("OK");
+
+ pop_settings();
+}
+
+static void madvise_collapse(const char *msg, char *p, int nr_hpages,
+ struct mem_ops *ops, bool expect)
+{
+ /* Sanity check */
+ if (!ops->check_huge(p, 0)) {
+ printf("Unexpected huge page\n");
+ exit(EXIT_FAILURE);
+ }
+ __madvise_collapse(msg, p, nr_hpages, ops, expect);
+}
+
+#define TICK 500000
+static bool wait_for_scan(const char *msg, char *p, int nr_hpages,
+ struct mem_ops *ops)
+{
+ int full_scans;
+ int timeout = 6; /* 3 seconds */
+
+ /* Sanity check */
+ if (!ops->check_huge(p, 0)) {
+ printf("Unexpected huge page\n");
+ exit(EXIT_FAILURE);
+ }
+
+ madvise(p, nr_hpages * hpage_pmd_size, MADV_HUGEPAGE);
+
+ /* Wait until the second full_scan completed */
+ full_scans = read_num("khugepaged/full_scans") + 2;
+
+ printf("%s...", msg);
+ while (timeout--) {
+ if (ops->check_huge(p, nr_hpages))
+ break;
+ if (read_num("khugepaged/full_scans") >= full_scans)
+ break;
+ printf(".");
+ usleep(TICK);
+ }
+
+ madvise(p, nr_hpages * hpage_pmd_size, MADV_NOHUGEPAGE);
+
+ return timeout == -1;
+}
+
+static void khugepaged_collapse(const char *msg, char *p, int nr_hpages,
+ struct mem_ops *ops, bool expect)
+{
+ if (wait_for_scan(msg, p, nr_hpages, ops)) {
+ if (expect)
+ fail("Timeout");
+ else
+ success("OK");
+ return;
+ }
+
+ /*
+ * For file and shmem memory, khugepaged only retracts pte entries after
+ * putting the new hugepage in the page cache. The hugepage must be
+ * subsequently refaulted to install the pmd mapping for the mm.
+ */
+ if (ops != &__anon_ops)
+ ops->fault(p, 0, nr_hpages * hpage_pmd_size);
+
+ if (ops->check_huge(p, expect ? nr_hpages : 0))
+ success("OK");
+ else
+ fail("Fail");
+}
+
+static struct collapse_context __khugepaged_context = {
+ .collapse = &khugepaged_collapse,
+ .enforce_pte_scan_limits = true,
+ .name = "khugepaged",
+};
+
+static struct collapse_context __madvise_context = {
+ .collapse = &madvise_collapse,
+ .enforce_pte_scan_limits = false,
+ .name = "madvise",
+};
+
+static bool is_tmpfs(struct mem_ops *ops)
+{
+ return ops == &__file_ops && finfo.type == VMA_SHMEM;
+}
+
+static void alloc_at_fault(void)
+{
+ struct settings settings = *current_settings();
+ char *p;
+
+ settings.thp_enabled = THP_ALWAYS;
+ push_settings(&settings);
+
+ p = alloc_mapping(1);
+ *p = 1;
+ printf("Allocate huge page on fault...");
+ if (check_huge_anon(p, 1, hpage_pmd_size))
+ success("OK");
+ else
+ fail("Fail");
+
+ pop_settings();
+
+ madvise(p, page_size, MADV_DONTNEED);
+ printf("Split huge PMD on MADV_DONTNEED...");
+ if (check_huge_anon(p, 0, hpage_pmd_size))
+ success("OK");
+ else
+ fail("Fail");
+ munmap(p, hpage_pmd_size);
+}
+
+static void collapse_full(struct collapse_context *c, struct mem_ops *ops)
+{
+ void *p;
+ int nr_hpages = 4;
+ unsigned long size = nr_hpages * hpage_pmd_size;
+
+ p = ops->setup_area(nr_hpages);
+ ops->fault(p, 0, size);
+ c->collapse("Collapse multiple fully populated PTE table", p, nr_hpages,
+ ops, true);
+ validate_memory(p, 0, size);
+ ops->cleanup_area(p, size);
+}
+
+static void collapse_empty(struct collapse_context *c, struct mem_ops *ops)
+{
+ void *p;
+
+ p = ops->setup_area(1);
+ c->collapse("Do not collapse empty PTE table", p, 1, ops, false);
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_single_pte_entry(struct collapse_context *c, struct mem_ops *ops)
+{
+ void *p;
+
+ p = ops->setup_area(1);
+ ops->fault(p, 0, page_size);
+ c->collapse("Collapse PTE table with single PTE entry present", p,
+ 1, ops, true);
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_max_ptes_none(struct collapse_context *c, struct mem_ops *ops)
+{
+ int max_ptes_none = hpage_pmd_nr / 2;
+ struct settings settings = *current_settings();
+ void *p;
+
+ settings.khugepaged.max_ptes_none = max_ptes_none;
+ push_settings(&settings);
+
+ p = ops->setup_area(1);
+
+ if (is_tmpfs(ops)) {
+ /* shmem pages always in the page cache */
+ printf("tmpfs...");
+ skip("Skip");
+ goto skip;
+ }
+
+ ops->fault(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
+ c->collapse("Maybe collapse with max_ptes_none exceeded", p, 1,
+ ops, !c->enforce_pte_scan_limits);
+ validate_memory(p, 0, (hpage_pmd_nr - max_ptes_none - 1) * page_size);
+
+ if (c->enforce_pte_scan_limits) {
+ ops->fault(p, 0, (hpage_pmd_nr - max_ptes_none) * page_size);
+ c->collapse("Collapse with max_ptes_none PTEs empty", p, 1, ops,
+ true);
+ validate_memory(p, 0,
+ (hpage_pmd_nr - max_ptes_none) * page_size);
+ }
+skip:
+ ops->cleanup_area(p, hpage_pmd_size);
+ pop_settings();
+}
+
+static void collapse_swapin_single_pte(struct collapse_context *c, struct mem_ops *ops)
+{
+ void *p;
+
+ p = ops->setup_area(1);
+ ops->fault(p, 0, hpage_pmd_size);
+
+ printf("Swapout one page...");
+ if (madvise(p, page_size, MADV_PAGEOUT)) {
+ perror("madvise(MADV_PAGEOUT)");
+ exit(EXIT_FAILURE);
+ }
+ if (check_swap(p, page_size)) {
+ success("OK");
+ } else {
+ fail("Fail");
+ goto out;
+ }
+
+ c->collapse("Collapse with swapping in single PTE entry", p, 1, ops,
+ true);
+ validate_memory(p, 0, hpage_pmd_size);
+out:
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_max_ptes_swap(struct collapse_context *c, struct mem_ops *ops)
+{
+ int max_ptes_swap = read_num("khugepaged/max_ptes_swap");
+ void *p;
+
+ p = ops->setup_area(1);
+ ops->fault(p, 0, hpage_pmd_size);
+
+ printf("Swapout %d of %d pages...", max_ptes_swap + 1, hpage_pmd_nr);
+ if (madvise(p, (max_ptes_swap + 1) * page_size, MADV_PAGEOUT)) {
+ perror("madvise(MADV_PAGEOUT)");
+ exit(EXIT_FAILURE);
+ }
+ if (check_swap(p, (max_ptes_swap + 1) * page_size)) {
+ success("OK");
+ } else {
+ fail("Fail");
+ goto out;
+ }
+
+ c->collapse("Maybe collapse with max_ptes_swap exceeded", p, 1, ops,
+ !c->enforce_pte_scan_limits);
+ validate_memory(p, 0, hpage_pmd_size);
+
+ if (c->enforce_pte_scan_limits) {
+ ops->fault(p, 0, hpage_pmd_size);
+ printf("Swapout %d of %d pages...", max_ptes_swap,
+ hpage_pmd_nr);
+ if (madvise(p, max_ptes_swap * page_size, MADV_PAGEOUT)) {
+ perror("madvise(MADV_PAGEOUT)");
+ exit(EXIT_FAILURE);
+ }
+ if (check_swap(p, max_ptes_swap * page_size)) {
+ success("OK");
+ } else {
+ fail("Fail");
+ goto out;
+ }
+
+ c->collapse("Collapse with max_ptes_swap pages swapped out", p,
+ 1, ops, true);
+ validate_memory(p, 0, hpage_pmd_size);
+ }
+out:
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_single_pte_entry_compound(struct collapse_context *c, struct mem_ops *ops)
+{
+ void *p;
+
+ p = alloc_hpage(ops);
+
+ if (is_tmpfs(ops)) {
+ /* MADV_DONTNEED won't evict tmpfs pages */
+ printf("tmpfs...");
+ skip("Skip");
+ goto skip;
+ }
+
+ madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
+ printf("Split huge page leaving single PTE mapping compound page...");
+ madvise(p + page_size, hpage_pmd_size - page_size, MADV_DONTNEED);
+ if (ops->check_huge(p, 0))
+ success("OK");
+ else
+ fail("Fail");
+
+ c->collapse("Collapse PTE table with single PTE mapping compound page",
+ p, 1, ops, true);
+ validate_memory(p, 0, page_size);
+skip:
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_full_of_compound(struct collapse_context *c, struct mem_ops *ops)
+{
+ void *p;
+
+ p = alloc_hpage(ops);
+ printf("Split huge page leaving single PTE page table full of compound pages...");
+ madvise(p, page_size, MADV_NOHUGEPAGE);
+ madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
+ if (ops->check_huge(p, 0))
+ success("OK");
+ else
+ fail("Fail");
+
+ c->collapse("Collapse PTE table full of compound pages", p, 1, ops,
+ true);
+ validate_memory(p, 0, hpage_pmd_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_compound_extreme(struct collapse_context *c, struct mem_ops *ops)
+{
+ void *p;
+ int i;
+
+ p = ops->setup_area(1);
+ for (i = 0; i < hpage_pmd_nr; i++) {
+ printf("\rConstruct PTE page table full of different PTE-mapped compound pages %3d/%d...",
+ i + 1, hpage_pmd_nr);
+
+ madvise(BASE_ADDR, hpage_pmd_size, MADV_HUGEPAGE);
+ ops->fault(BASE_ADDR, 0, hpage_pmd_size);
+ if (!ops->check_huge(BASE_ADDR, 1)) {
+ printf("Failed to allocate huge page\n");
+ exit(EXIT_FAILURE);
+ }
+ madvise(BASE_ADDR, hpage_pmd_size, MADV_NOHUGEPAGE);
+
+ p = mremap(BASE_ADDR - i * page_size,
+ i * page_size + hpage_pmd_size,
+ (i + 1) * page_size,
+ MREMAP_MAYMOVE | MREMAP_FIXED,
+ BASE_ADDR + 2 * hpage_pmd_size);
+ if (p == MAP_FAILED) {
+ perror("mremap+unmap");
+ exit(EXIT_FAILURE);
+ }
+
+ p = mremap(BASE_ADDR + 2 * hpage_pmd_size,
+ (i + 1) * page_size,
+ (i + 1) * page_size + hpage_pmd_size,
+ MREMAP_MAYMOVE | MREMAP_FIXED,
+ BASE_ADDR - (i + 1) * page_size);
+ if (p == MAP_FAILED) {
+ perror("mremap+alloc");
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ ops->cleanup_area(BASE_ADDR, hpage_pmd_size);
+ ops->fault(p, 0, hpage_pmd_size);
+ if (!ops->check_huge(p, 1))
+ success("OK");
+ else
+ fail("Fail");
+
+ c->collapse("Collapse PTE table full of different compound pages", p, 1,
+ ops, true);
+
+ validate_memory(p, 0, hpage_pmd_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_fork(struct collapse_context *c, struct mem_ops *ops)
+{
+ int wstatus;
+ void *p;
+
+ p = ops->setup_area(1);
+
+ printf("Allocate small page...");
+ ops->fault(p, 0, page_size);
+ if (ops->check_huge(p, 0))
+ success("OK");
+ else
+ fail("Fail");
+
+ printf("Share small page over fork()...");
+ if (!fork()) {
+ /* Do not touch settings on child exit */
+ skip_settings_restore = true;
+ exit_status = 0;
+
+ if (ops->check_huge(p, 0))
+ success("OK");
+ else
+ fail("Fail");
+
+ ops->fault(p, page_size, 2 * page_size);
+ c->collapse("Collapse PTE table with single page shared with parent process",
+ p, 1, ops, true);
+
+ validate_memory(p, 0, page_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+ exit(exit_status);
+ }
+
+ wait(&wstatus);
+ exit_status += WEXITSTATUS(wstatus);
+
+ printf("Check if parent still has small page...");
+ if (ops->check_huge(p, 0))
+ success("OK");
+ else
+ fail("Fail");
+ validate_memory(p, 0, page_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_fork_compound(struct collapse_context *c, struct mem_ops *ops)
+{
+ int wstatus;
+ void *p;
+
+ p = alloc_hpage(ops);
+ printf("Share huge page over fork()...");
+ if (!fork()) {
+ /* Do not touch settings on child exit */
+ skip_settings_restore = true;
+ exit_status = 0;
+
+ if (ops->check_huge(p, 1))
+ success("OK");
+ else
+ fail("Fail");
+
+ printf("Split huge page PMD in child process...");
+ madvise(p, page_size, MADV_NOHUGEPAGE);
+ madvise(p, hpage_pmd_size, MADV_NOHUGEPAGE);
+ if (ops->check_huge(p, 0))
+ success("OK");
+ else
+ fail("Fail");
+ ops->fault(p, 0, page_size);
+
+ write_num("khugepaged/max_ptes_shared", hpage_pmd_nr - 1);
+ c->collapse("Collapse PTE table full of compound pages in child",
+ p, 1, ops, true);
+ write_num("khugepaged/max_ptes_shared",
+ current_settings()->khugepaged.max_ptes_shared);
+
+ validate_memory(p, 0, hpage_pmd_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+ exit(exit_status);
+ }
+
+ wait(&wstatus);
+ exit_status += WEXITSTATUS(wstatus);
+
+ printf("Check if parent still has huge page...");
+ if (ops->check_huge(p, 1))
+ success("OK");
+ else
+ fail("Fail");
+ validate_memory(p, 0, hpage_pmd_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void collapse_max_ptes_shared(struct collapse_context *c, struct mem_ops *ops)
+{
+ int max_ptes_shared = read_num("khugepaged/max_ptes_shared");
+ int wstatus;
+ void *p;
+
+ p = alloc_hpage(ops);
+ printf("Share huge page over fork()...");
+ if (!fork()) {
+ /* Do not touch settings on child exit */
+ skip_settings_restore = true;
+ exit_status = 0;
+
+ if (ops->check_huge(p, 1))
+ success("OK");
+ else
+ fail("Fail");
+
+ printf("Trigger CoW on page %d of %d...",
+ hpage_pmd_nr - max_ptes_shared - 1, hpage_pmd_nr);
+ ops->fault(p, 0, (hpage_pmd_nr - max_ptes_shared - 1) * page_size);
+ if (ops->check_huge(p, 0))
+ success("OK");
+ else
+ fail("Fail");
+
+ c->collapse("Maybe collapse with max_ptes_shared exceeded", p,
+ 1, ops, !c->enforce_pte_scan_limits);
+
+ if (c->enforce_pte_scan_limits) {
+ printf("Trigger CoW on page %d of %d...",
+ hpage_pmd_nr - max_ptes_shared, hpage_pmd_nr);
+ ops->fault(p, 0, (hpage_pmd_nr - max_ptes_shared) *
+ page_size);
+ if (ops->check_huge(p, 0))
+ success("OK");
+ else
+ fail("Fail");
+
+ c->collapse("Collapse with max_ptes_shared PTEs shared",
+ p, 1, ops, true);
+ }
+
+ validate_memory(p, 0, hpage_pmd_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+ exit(exit_status);
+ }
+
+ wait(&wstatus);
+ exit_status += WEXITSTATUS(wstatus);
+
+ printf("Check if parent still has huge page...");
+ if (ops->check_huge(p, 1))
+ success("OK");
+ else
+ fail("Fail");
+ validate_memory(p, 0, hpage_pmd_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+static void madvise_collapse_existing_thps(struct collapse_context *c,
+ struct mem_ops *ops)
+{
+ void *p;
+
+ p = ops->setup_area(1);
+ ops->fault(p, 0, hpage_pmd_size);
+ c->collapse("Collapse fully populated PTE table...", p, 1, ops, true);
+ validate_memory(p, 0, hpage_pmd_size);
+
+ /* c->collapse() will find a hugepage and complain - call directly. */
+ __madvise_collapse("Re-collapse PMD-mapped hugepage", p, 1, ops, true);
+ validate_memory(p, 0, hpage_pmd_size);
+ ops->cleanup_area(p, hpage_pmd_size);
+}
+
+/*
+ * Test race with khugepaged where page tables have been retracted and
+ * pmd cleared.
+ */
+static void madvise_retracted_page_tables(struct collapse_context *c,
+ struct mem_ops *ops)
+{
+ void *p;
+ int nr_hpages = 1;
+ unsigned long size = nr_hpages * hpage_pmd_size;
+
+ p = ops->setup_area(nr_hpages);
+ ops->fault(p, 0, size);
+
+ /* Let khugepaged collapse and leave pmd cleared */
+ if (wait_for_scan("Collapse and leave PMD cleared", p, nr_hpages,
+ ops)) {
+ fail("Timeout");
+ return;
+ }
+ success("OK");
+ c->collapse("Install huge PMD from page cache", p, nr_hpages, ops,
+ true);
+ validate_memory(p, 0, size);
+ ops->cleanup_area(p, size);
+}
+
+static void usage(void)
+{
+ fprintf(stderr, "\nUsage: ./khugepaged <test type> [dir]\n\n");
+ fprintf(stderr, "\t<test type>\t: <context>:<mem_type>\n");
+ fprintf(stderr, "\t<context>\t: [all|khugepaged|madvise]\n");
+ fprintf(stderr, "\t<mem_type>\t: [all|anon|file|shmem]\n");
+ fprintf(stderr, "\n\t\"file,all\" mem_type requires [dir] argument\n");
+ fprintf(stderr, "\n\t\"file,all\" mem_type requires kernel built with\n");
+ fprintf(stderr, "\tCONFIG_READ_ONLY_THP_FOR_FS=y\n");
+ fprintf(stderr, "\n\tif [dir] is a (sub)directory of a tmpfs mount, tmpfs must be\n");
+ fprintf(stderr, "\tmounted with huge=madvise option for khugepaged tests to work\n");
+ exit(1);
+}
+
+static void parse_test_type(int argc, const char **argv)
+{
+ char *buf;
+ const char *token;
+
+ if (argc == 1) {
+ /* Backwards compatibility */
+ khugepaged_context = &__khugepaged_context;
+ madvise_context = &__madvise_context;
+ anon_ops = &__anon_ops;
+ return;
+ }
+
+ buf = strdup(argv[1]);
+ token = strsep(&buf, ":");
+
+ if (!strcmp(token, "all")) {
+ khugepaged_context = &__khugepaged_context;
+ madvise_context = &__madvise_context;
+ } else if (!strcmp(token, "khugepaged")) {
+ khugepaged_context = &__khugepaged_context;
+ } else if (!strcmp(token, "madvise")) {
+ madvise_context = &__madvise_context;
+ } else {
+ usage();
+ }
+
+ if (!buf)
+ usage();
+
+ if (!strcmp(buf, "all")) {
+ file_ops = &__file_ops;
+ anon_ops = &__anon_ops;
+ shmem_ops = &__shmem_ops;
+ } else if (!strcmp(buf, "anon")) {
+ anon_ops = &__anon_ops;
+ } else if (!strcmp(buf, "file")) {
+ file_ops = &__file_ops;
+ } else if (!strcmp(buf, "shmem")) {
+ shmem_ops = &__shmem_ops;
+ } else {
+ usage();
+ }
+
+ if (!file_ops)
+ return;
+
+ if (argc != 3)
+ usage();
+}
+
+int main(int argc, const char **argv)
+{
+ struct settings default_settings = {
+ .thp_enabled = THP_MADVISE,
+ .thp_defrag = THP_DEFRAG_ALWAYS,
+ .shmem_enabled = SHMEM_ADVISE,
+ .use_zero_page = 0,
+ .khugepaged = {
+ .defrag = 1,
+ .alloc_sleep_millisecs = 10,
+ .scan_sleep_millisecs = 10,
+ },
+ /*
+ * When testing file-backed memory, the collapse path
+ * looks at how many pages are found in the page cache, not
+ * what pages are mapped. Disable read ahead optimization so
+ * pages don't find their way into the page cache unless
+ * we mem_ops->fault() them in.
+ */
+ .read_ahead_kb = 0,
+ };
+
+ parse_test_type(argc, argv);
+
+ if (file_ops)
+ get_finfo(argv[2]);
+
+ setbuf(stdout, NULL);
+
+ page_size = getpagesize();
+ hpage_pmd_size = read_pmd_pagesize();
+ hpage_pmd_nr = hpage_pmd_size / page_size;
+
+ default_settings.khugepaged.max_ptes_none = hpage_pmd_nr - 1;
+ default_settings.khugepaged.max_ptes_swap = hpage_pmd_nr / 8;
+ default_settings.khugepaged.max_ptes_shared = hpage_pmd_nr / 2;
+ default_settings.khugepaged.pages_to_scan = hpage_pmd_nr * 8;
+
+ save_settings();
+ push_settings(&default_settings);
+
+ alloc_at_fault();
+
+#define TEST(t, c, o) do { \
+ if (c && o) { \
+ printf("\nRun test: " #t " (%s:%s)\n", c->name, o->name); \
+ t(c, o); \
+ } \
+ } while (0)
+
+ TEST(collapse_full, khugepaged_context, anon_ops);
+ TEST(collapse_full, khugepaged_context, file_ops);
+ TEST(collapse_full, khugepaged_context, shmem_ops);
+ TEST(collapse_full, madvise_context, anon_ops);
+ TEST(collapse_full, madvise_context, file_ops);
+ TEST(collapse_full, madvise_context, shmem_ops);
+
+ TEST(collapse_empty, khugepaged_context, anon_ops);
+ TEST(collapse_empty, madvise_context, anon_ops);
+
+ TEST(collapse_single_pte_entry, khugepaged_context, anon_ops);
+ TEST(collapse_single_pte_entry, khugepaged_context, file_ops);
+ TEST(collapse_single_pte_entry, khugepaged_context, shmem_ops);
+ TEST(collapse_single_pte_entry, madvise_context, anon_ops);
+ TEST(collapse_single_pte_entry, madvise_context, file_ops);
+ TEST(collapse_single_pte_entry, madvise_context, shmem_ops);
+
+ TEST(collapse_max_ptes_none, khugepaged_context, anon_ops);
+ TEST(collapse_max_ptes_none, khugepaged_context, file_ops);
+ TEST(collapse_max_ptes_none, madvise_context, anon_ops);
+ TEST(collapse_max_ptes_none, madvise_context, file_ops);
+
+ TEST(collapse_single_pte_entry_compound, khugepaged_context, anon_ops);
+ TEST(collapse_single_pte_entry_compound, khugepaged_context, file_ops);
+ TEST(collapse_single_pte_entry_compound, madvise_context, anon_ops);
+ TEST(collapse_single_pte_entry_compound, madvise_context, file_ops);
+
+ TEST(collapse_full_of_compound, khugepaged_context, anon_ops);
+ TEST(collapse_full_of_compound, khugepaged_context, file_ops);
+ TEST(collapse_full_of_compound, khugepaged_context, shmem_ops);
+ TEST(collapse_full_of_compound, madvise_context, anon_ops);
+ TEST(collapse_full_of_compound, madvise_context, file_ops);
+ TEST(collapse_full_of_compound, madvise_context, shmem_ops);
+
+ TEST(collapse_compound_extreme, khugepaged_context, anon_ops);
+ TEST(collapse_compound_extreme, madvise_context, anon_ops);
+
+ TEST(collapse_swapin_single_pte, khugepaged_context, anon_ops);
+ TEST(collapse_swapin_single_pte, madvise_context, anon_ops);
+
+ TEST(collapse_max_ptes_swap, khugepaged_context, anon_ops);
+ TEST(collapse_max_ptes_swap, madvise_context, anon_ops);
+
+ TEST(collapse_fork, khugepaged_context, anon_ops);
+ TEST(collapse_fork, madvise_context, anon_ops);
+
+ TEST(collapse_fork_compound, khugepaged_context, anon_ops);
+ TEST(collapse_fork_compound, madvise_context, anon_ops);
+
+ TEST(collapse_max_ptes_shared, khugepaged_context, anon_ops);
+ TEST(collapse_max_ptes_shared, madvise_context, anon_ops);
+
+ TEST(madvise_collapse_existing_thps, madvise_context, anon_ops);
+ TEST(madvise_collapse_existing_thps, madvise_context, file_ops);
+ TEST(madvise_collapse_existing_thps, madvise_context, shmem_ops);
+
+ TEST(madvise_retracted_page_tables, madvise_context, file_ops);
+ TEST(madvise_retracted_page_tables, madvise_context, shmem_ops);
+
+ restore_settings(0);
+}
diff --git a/tools/testing/selftests/mm/ksm_functional_tests.c b/tools/testing/selftests/mm/ksm_functional_tests.c
new file mode 100644
index 000000000000..d8b5b4930412
--- /dev/null
+++ b/tools/testing/selftests/mm/ksm_functional_tests.c
@@ -0,0 +1,279 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * KSM functional tests
+ *
+ * Copyright 2022, Red Hat, Inc.
+ *
+ * Author(s): David Hildenbrand <david@redhat.com>
+ */
+#define _GNU_SOURCE
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#include <sys/ioctl.h>
+#include <linux/userfaultfd.h>
+
+#include "../kselftest.h"
+#include "vm_util.h"
+
+#define KiB 1024u
+#define MiB (1024 * KiB)
+
+static int ksm_fd;
+static int ksm_full_scans_fd;
+static int pagemap_fd;
+static size_t pagesize;
+
+static bool range_maps_duplicates(char *addr, unsigned long size)
+{
+ unsigned long offs_a, offs_b, pfn_a, pfn_b;
+
+ /*
+ * There is no easy way to check if there are KSM pages mapped into
+ * this range. We only check that the range does not map the same PFN
+ * twice by comparing each pair of mapped pages.
+ */
+ for (offs_a = 0; offs_a < size; offs_a += pagesize) {
+ pfn_a = pagemap_get_pfn(pagemap_fd, addr + offs_a);
+ /* Page not present or PFN not exposed by the kernel. */
+ if (pfn_a == -1ul || !pfn_a)
+ continue;
+
+ for (offs_b = offs_a + pagesize; offs_b < size;
+ offs_b += pagesize) {
+ pfn_b = pagemap_get_pfn(pagemap_fd, addr + offs_b);
+ if (pfn_b == -1ul || !pfn_b)
+ continue;
+ if (pfn_a == pfn_b)
+ return true;
+ }
+ }
+ return false;
+}
+
+static long ksm_get_full_scans(void)
+{
+ char buf[10];
+ ssize_t ret;
+
+ ret = pread(ksm_full_scans_fd, buf, sizeof(buf) - 1, 0);
+ if (ret <= 0)
+ return -errno;
+ buf[ret] = 0;
+
+ return strtol(buf, NULL, 10);
+}
+
+static int ksm_merge(void)
+{
+ long start_scans, end_scans;
+
+ /* Wait for two full scans such that any possible merging happened. */
+ start_scans = ksm_get_full_scans();
+ if (start_scans < 0)
+ return start_scans;
+ if (write(ksm_fd, "1", 1) != 1)
+ return -errno;
+ do {
+ end_scans = ksm_get_full_scans();
+ if (end_scans < 0)
+ return end_scans;
+ } while (end_scans < start_scans + 2);
+
+ return 0;
+}
+
+static char *mmap_and_merge_range(char val, unsigned long size)
+{
+ char *map;
+
+ map = mmap(NULL, size, PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_ANON, -1, 0);
+ if (map == MAP_FAILED) {
+ ksft_test_result_fail("mmap() failed\n");
+ return MAP_FAILED;
+ }
+
+ /* Don't use THP. Ignore if THP are not around on a kernel. */
+ if (madvise(map, size, MADV_NOHUGEPAGE) && errno != EINVAL) {
+ ksft_test_result_fail("MADV_NOHUGEPAGE failed\n");
+ goto unmap;
+ }
+
+ /* Make sure each page contains the same values to merge them. */
+ memset(map, val, size);
+ if (madvise(map, size, MADV_MERGEABLE)) {
+ ksft_test_result_fail("MADV_MERGEABLE failed\n");
+ goto unmap;
+ }
+
+ /* Run KSM to trigger merging and wait. */
+ if (ksm_merge()) {
+ ksft_test_result_fail("Running KSM failed\n");
+ goto unmap;
+ }
+ return map;
+unmap:
+ munmap(map, size);
+ return MAP_FAILED;
+}
+
+static void test_unmerge(void)
+{
+ const unsigned int size = 2 * MiB;
+ char *map;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ map = mmap_and_merge_range(0xcf, size);
+ if (map == MAP_FAILED)
+ return;
+
+ if (madvise(map, size, MADV_UNMERGEABLE)) {
+ ksft_test_result_fail("MADV_UNMERGEABLE failed\n");
+ goto unmap;
+ }
+
+ ksft_test_result(!range_maps_duplicates(map, size),
+ "Pages were unmerged\n");
+unmap:
+ munmap(map, size);
+}
+
+static void test_unmerge_discarded(void)
+{
+ const unsigned int size = 2 * MiB;
+ char *map;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ map = mmap_and_merge_range(0xcf, size);
+ if (map == MAP_FAILED)
+ return;
+
+ /* Discard half of all mapped pages so we have pte_none() entries. */
+ if (madvise(map, size / 2, MADV_DONTNEED)) {
+ ksft_test_result_fail("MADV_DONTNEED failed\n");
+ goto unmap;
+ }
+
+ if (madvise(map, size, MADV_UNMERGEABLE)) {
+ ksft_test_result_fail("MADV_UNMERGEABLE failed\n");
+ goto unmap;
+ }
+
+ ksft_test_result(!range_maps_duplicates(map, size),
+ "Pages were unmerged\n");
+unmap:
+ munmap(map, size);
+}
+
+#ifdef __NR_userfaultfd
+static void test_unmerge_uffd_wp(void)
+{
+ struct uffdio_writeprotect uffd_writeprotect;
+ struct uffdio_register uffdio_register;
+ const unsigned int size = 2 * MiB;
+ struct uffdio_api uffdio_api;
+ char *map;
+ int uffd;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ map = mmap_and_merge_range(0xcf, size);
+ if (map == MAP_FAILED)
+ return;
+
+ /* See if UFFD is around. */
+ uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
+ if (uffd < 0) {
+ ksft_test_result_skip("__NR_userfaultfd failed\n");
+ goto unmap;
+ }
+
+ /* See if UFFD-WP is around. */
+ uffdio_api.api = UFFD_API;
+ uffdio_api.features = UFFD_FEATURE_PAGEFAULT_FLAG_WP;
+ if (ioctl(uffd, UFFDIO_API, &uffdio_api) < 0) {
+ ksft_test_result_fail("UFFDIO_API failed\n");
+ goto close_uffd;
+ }
+ if (!(uffdio_api.features & UFFD_FEATURE_PAGEFAULT_FLAG_WP)) {
+ ksft_test_result_skip("UFFD_FEATURE_PAGEFAULT_FLAG_WP not available\n");
+ goto close_uffd;
+ }
+
+ /* Register UFFD-WP, no need for an actual handler. */
+ uffdio_register.range.start = (unsigned long) map;
+ uffdio_register.range.len = size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_WP;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) < 0) {
+ ksft_test_result_fail("UFFDIO_REGISTER_MODE_WP failed\n");
+ goto close_uffd;
+ }
+
+ /* Write-protect the range using UFFD-WP. */
+ uffd_writeprotect.range.start = (unsigned long) map;
+ uffd_writeprotect.range.len = size;
+ uffd_writeprotect.mode = UFFDIO_WRITEPROTECT_MODE_WP;
+ if (ioctl(uffd, UFFDIO_WRITEPROTECT, &uffd_writeprotect)) {
+ ksft_test_result_fail("UFFDIO_WRITEPROTECT failed\n");
+ goto close_uffd;
+ }
+
+ if (madvise(map, size, MADV_UNMERGEABLE)) {
+ ksft_test_result_fail("MADV_UNMERGEABLE failed\n");
+ goto close_uffd;
+ }
+
+ ksft_test_result(!range_maps_duplicates(map, size),
+ "Pages were unmerged\n");
+close_uffd:
+ close(uffd);
+unmap:
+ munmap(map, size);
+}
+#endif
+
+int main(int argc, char **argv)
+{
+ unsigned int tests = 2;
+ int err;
+
+#ifdef __NR_userfaultfd
+ tests++;
+#endif
+
+ ksft_print_header();
+ ksft_set_plan(tests);
+
+ pagesize = getpagesize();
+
+ ksm_fd = open("/sys/kernel/mm/ksm/run", O_RDWR);
+ if (ksm_fd < 0)
+ ksft_exit_skip("open(\"/sys/kernel/mm/ksm/run\") failed\n");
+ ksm_full_scans_fd = open("/sys/kernel/mm/ksm/full_scans", O_RDONLY);
+ if (ksm_full_scans_fd < 0)
+ ksft_exit_skip("open(\"/sys/kernel/mm/ksm/full_scans\") failed\n");
+ pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
+ if (pagemap_fd < 0)
+ ksft_exit_skip("open(\"/proc/self/pagemap\") failed\n");
+
+ test_unmerge();
+ test_unmerge_discarded();
+#ifdef __NR_userfaultfd
+ test_unmerge_uffd_wp();
+#endif
+
+ err = ksft_get_fail_cnt();
+ if (err)
+ ksft_exit_fail_msg("%d out of %d tests failed\n",
+ err, ksft_test_num());
+ return ksft_exit_pass();
+}
diff --git a/tools/testing/selftests/mm/ksm_tests.c b/tools/testing/selftests/mm/ksm_tests.c
new file mode 100644
index 000000000000..f9eb4d67e0dd
--- /dev/null
+++ b/tools/testing/selftests/mm/ksm_tests.c
@@ -0,0 +1,849 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <sys/mman.h>
+#include <stdbool.h>
+#include <time.h>
+#include <string.h>
+#include <numa.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <err.h>
+
+#include "../kselftest.h"
+#include <include/vdso/time64.h>
+#include "util.h"
+
+#define KSM_SYSFS_PATH "/sys/kernel/mm/ksm/"
+#define KSM_FP(s) (KSM_SYSFS_PATH s)
+#define KSM_SCAN_LIMIT_SEC_DEFAULT 120
+#define KSM_PAGE_COUNT_DEFAULT 10l
+#define KSM_PROT_STR_DEFAULT "rw"
+#define KSM_USE_ZERO_PAGES_DEFAULT false
+#define KSM_MERGE_ACROSS_NODES_DEFAULT true
+#define MB (1ul << 20)
+
+struct ksm_sysfs {
+ unsigned long max_page_sharing;
+ unsigned long merge_across_nodes;
+ unsigned long pages_to_scan;
+ unsigned long run;
+ unsigned long sleep_millisecs;
+ unsigned long stable_node_chains_prune_millisecs;
+ unsigned long use_zero_pages;
+};
+
+enum ksm_test_name {
+ CHECK_KSM_MERGE,
+ CHECK_KSM_UNMERGE,
+ CHECK_KSM_ZERO_PAGE_MERGE,
+ CHECK_KSM_NUMA_MERGE,
+ KSM_MERGE_TIME,
+ KSM_MERGE_TIME_HUGE_PAGES,
+ KSM_UNMERGE_TIME,
+ KSM_COW_TIME
+};
+
+static int ksm_write_sysfs(const char *file_path, unsigned long val)
+{
+ FILE *f = fopen(file_path, "w");
+
+ if (!f) {
+ fprintf(stderr, "f %s\n", file_path);
+ perror("fopen");
+ return 1;
+ }
+ if (fprintf(f, "%lu", val) < 0) {
+ perror("fprintf");
+ fclose(f);
+ return 1;
+ }
+ fclose(f);
+
+ return 0;
+}
+
+static int ksm_read_sysfs(const char *file_path, unsigned long *val)
+{
+ FILE *f = fopen(file_path, "r");
+
+ if (!f) {
+ fprintf(stderr, "f %s\n", file_path);
+ perror("fopen");
+ return 1;
+ }
+ if (fscanf(f, "%lu", val) != 1) {
+ perror("fscanf");
+ fclose(f);
+ return 1;
+ }
+ fclose(f);
+
+ return 0;
+}
+
+static int str_to_prot(char *prot_str)
+{
+ int prot = 0;
+
+ if ((strchr(prot_str, 'r')) != NULL)
+ prot |= PROT_READ;
+ if ((strchr(prot_str, 'w')) != NULL)
+ prot |= PROT_WRITE;
+ if ((strchr(prot_str, 'x')) != NULL)
+ prot |= PROT_EXEC;
+
+ return prot;
+}
+
+static void print_help(void)
+{
+ printf("usage: ksm_tests [-h] <test type> [-a prot] [-p page_count] [-l timeout]\n"
+ "[-z use_zero_pages] [-m merge_across_nodes] [-s size]\n");
+
+ printf("Supported <test type>:\n"
+ " -M (page merging)\n"
+ " -Z (zero pages merging)\n"
+ " -N (merging of pages in different NUMA nodes)\n"
+ " -U (page unmerging)\n"
+ " -P evaluate merging time and speed.\n"
+ " For this test, the size of duplicated memory area (in MiB)\n"
+ " must be provided using -s option\n"
+ " -H evaluate merging time and speed of area allocated mostly with huge pages\n"
+ " For this test, the size of duplicated memory area (in MiB)\n"
+ " must be provided using -s option\n"
+ " -D evaluate unmerging time and speed when disabling KSM.\n"
+ " For this test, the size of duplicated memory area (in MiB)\n"
+ " must be provided using -s option\n"
+ " -C evaluate the time required to break COW of merged pages.\n\n");
+
+ printf(" -a: specify the access protections of pages.\n"
+ " <prot> must be of the form [rwx].\n"
+ " Default: %s\n", KSM_PROT_STR_DEFAULT);
+ printf(" -p: specify the number of pages to test.\n"
+ " Default: %ld\n", KSM_PAGE_COUNT_DEFAULT);
+ printf(" -l: limit the maximum running time (in seconds) for a test.\n"
+ " Default: %d seconds\n", KSM_SCAN_LIMIT_SEC_DEFAULT);
+ printf(" -z: change use_zero_pages tunable\n"
+ " Default: %d\n", KSM_USE_ZERO_PAGES_DEFAULT);
+ printf(" -m: change merge_across_nodes tunable\n"
+ " Default: %d\n", KSM_MERGE_ACROSS_NODES_DEFAULT);
+ printf(" -s: the size of duplicated memory area (in MiB)\n");
+
+ exit(0);
+}
+
+static void *allocate_memory(void *ptr, int prot, int mapping, char data, size_t map_size)
+{
+ void *map_ptr = mmap(ptr, map_size, PROT_WRITE, mapping, -1, 0);
+
+ if (!map_ptr) {
+ perror("mmap");
+ return NULL;
+ }
+ memset(map_ptr, data, map_size);
+ if (mprotect(map_ptr, map_size, prot)) {
+ perror("mprotect");
+ munmap(map_ptr, map_size);
+ return NULL;
+ }
+
+ return map_ptr;
+}
+
+static int ksm_do_scan(int scan_count, struct timespec start_time, int timeout)
+{
+ struct timespec cur_time;
+ unsigned long cur_scan, init_scan;
+
+ if (ksm_read_sysfs(KSM_FP("full_scans"), &init_scan))
+ return 1;
+ cur_scan = init_scan;
+
+ while (cur_scan < init_scan + scan_count) {
+ if (ksm_read_sysfs(KSM_FP("full_scans"), &cur_scan))
+ return 1;
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &cur_time)) {
+ perror("clock_gettime");
+ return 1;
+ }
+ if ((cur_time.tv_sec - start_time.tv_sec) > timeout) {
+ printf("Scan time limit exceeded\n");
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static int ksm_merge_pages(void *addr, size_t size, struct timespec start_time, int timeout)
+{
+ if (madvise(addr, size, MADV_MERGEABLE)) {
+ perror("madvise");
+ return 1;
+ }
+ if (ksm_write_sysfs(KSM_FP("run"), 1))
+ return 1;
+
+ /* Since merging occurs only after 2 scans, make sure to get at least 2 full scans */
+ if (ksm_do_scan(2, start_time, timeout))
+ return 1;
+
+ return 0;
+}
+
+static int ksm_unmerge_pages(void *addr, size_t size,
+ struct timespec start_time, int timeout)
+{
+ if (madvise(addr, size, MADV_UNMERGEABLE)) {
+ perror("madvise");
+ return 1;
+ }
+ return 0;
+}
+
+static bool assert_ksm_pages_count(long dupl_page_count)
+{
+ unsigned long max_page_sharing, pages_sharing, pages_shared;
+
+ if (ksm_read_sysfs(KSM_FP("pages_shared"), &pages_shared) ||
+ ksm_read_sysfs(KSM_FP("pages_sharing"), &pages_sharing) ||
+ ksm_read_sysfs(KSM_FP("max_page_sharing"), &max_page_sharing))
+ return false;
+
+ /*
+ * Since there must be at least 2 pages for merging and 1 page can be
+ * shared with the limited number of pages (max_page_sharing), sometimes
+ * there are 'leftover' pages that cannot be merged. For example, if there
+ * are 11 pages and max_page_sharing = 10, then only 10 pages will be
+ * merged and the 11th page won't be affected. As a result, when the number
+ * of duplicate pages is divided by max_page_sharing and the remainder is 1,
+ * pages_shared and pages_sharing values will be equal between dupl_page_count
+ * and dupl_page_count - 1.
+ */
+ if (dupl_page_count % max_page_sharing == 1 || dupl_page_count % max_page_sharing == 0) {
+ if (pages_shared == dupl_page_count / max_page_sharing &&
+ pages_sharing == pages_shared * (max_page_sharing - 1))
+ return true;
+ } else {
+ if (pages_shared == (dupl_page_count / max_page_sharing + 1) &&
+ pages_sharing == dupl_page_count - pages_shared)
+ return true;
+ }
+
+ return false;
+}
+
+static int ksm_save_def(struct ksm_sysfs *ksm_sysfs)
+{
+ if (ksm_read_sysfs(KSM_FP("max_page_sharing"), &ksm_sysfs->max_page_sharing) ||
+ numa_available() ? 0 :
+ ksm_read_sysfs(KSM_FP("merge_across_nodes"), &ksm_sysfs->merge_across_nodes) ||
+ ksm_read_sysfs(KSM_FP("sleep_millisecs"), &ksm_sysfs->sleep_millisecs) ||
+ ksm_read_sysfs(KSM_FP("pages_to_scan"), &ksm_sysfs->pages_to_scan) ||
+ ksm_read_sysfs(KSM_FP("run"), &ksm_sysfs->run) ||
+ ksm_read_sysfs(KSM_FP("stable_node_chains_prune_millisecs"),
+ &ksm_sysfs->stable_node_chains_prune_millisecs) ||
+ ksm_read_sysfs(KSM_FP("use_zero_pages"), &ksm_sysfs->use_zero_pages))
+ return 1;
+
+ return 0;
+}
+
+static int ksm_restore(struct ksm_sysfs *ksm_sysfs)
+{
+ if (ksm_write_sysfs(KSM_FP("max_page_sharing"), ksm_sysfs->max_page_sharing) ||
+ numa_available() ? 0 :
+ ksm_write_sysfs(KSM_FP("merge_across_nodes"), ksm_sysfs->merge_across_nodes) ||
+ ksm_write_sysfs(KSM_FP("pages_to_scan"), ksm_sysfs->pages_to_scan) ||
+ ksm_write_sysfs(KSM_FP("run"), ksm_sysfs->run) ||
+ ksm_write_sysfs(KSM_FP("sleep_millisecs"), ksm_sysfs->sleep_millisecs) ||
+ ksm_write_sysfs(KSM_FP("stable_node_chains_prune_millisecs"),
+ ksm_sysfs->stable_node_chains_prune_millisecs) ||
+ ksm_write_sysfs(KSM_FP("use_zero_pages"), ksm_sysfs->use_zero_pages))
+ return 1;
+
+ return 0;
+}
+
+static int check_ksm_merge(int mapping, int prot, long page_count, int timeout, size_t page_size)
+{
+ void *map_ptr;
+ struct timespec start_time;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ return KSFT_FAIL;
+ }
+
+ /* fill pages with the same data and merge them */
+ map_ptr = allocate_memory(NULL, prot, mapping, '*', page_size * page_count);
+ if (!map_ptr)
+ return KSFT_FAIL;
+
+ if (ksm_merge_pages(map_ptr, page_size * page_count, start_time, timeout))
+ goto err_out;
+
+ /* verify that the right number of pages are merged */
+ if (assert_ksm_pages_count(page_count)) {
+ printf("OK\n");
+ munmap(map_ptr, page_size * page_count);
+ return KSFT_PASS;
+ }
+
+err_out:
+ printf("Not OK\n");
+ munmap(map_ptr, page_size * page_count);
+ return KSFT_FAIL;
+}
+
+static int check_ksm_unmerge(int mapping, int prot, int timeout, size_t page_size)
+{
+ void *map_ptr;
+ struct timespec start_time;
+ int page_count = 2;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ return KSFT_FAIL;
+ }
+
+ /* fill pages with the same data and merge them */
+ map_ptr = allocate_memory(NULL, prot, mapping, '*', page_size * page_count);
+ if (!map_ptr)
+ return KSFT_FAIL;
+
+ if (ksm_merge_pages(map_ptr, page_size * page_count, start_time, timeout))
+ goto err_out;
+
+ /* change 1 byte in each of the 2 pages -- KSM must automatically unmerge them */
+ memset(map_ptr, '-', 1);
+ memset(map_ptr + page_size, '+', 1);
+
+ /* get at least 1 scan, so KSM can detect that the pages were modified */
+ if (ksm_do_scan(1, start_time, timeout))
+ goto err_out;
+
+ /* check that unmerging was successful and 0 pages are currently merged */
+ if (assert_ksm_pages_count(0)) {
+ printf("OK\n");
+ munmap(map_ptr, page_size * page_count);
+ return KSFT_PASS;
+ }
+
+err_out:
+ printf("Not OK\n");
+ munmap(map_ptr, page_size * page_count);
+ return KSFT_FAIL;
+}
+
+static int check_ksm_zero_page_merge(int mapping, int prot, long page_count, int timeout,
+ bool use_zero_pages, size_t page_size)
+{
+ void *map_ptr;
+ struct timespec start_time;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ return KSFT_FAIL;
+ }
+
+ if (ksm_write_sysfs(KSM_FP("use_zero_pages"), use_zero_pages))
+ return KSFT_FAIL;
+
+ /* fill pages with zero and try to merge them */
+ map_ptr = allocate_memory(NULL, prot, mapping, 0, page_size * page_count);
+ if (!map_ptr)
+ return KSFT_FAIL;
+
+ if (ksm_merge_pages(map_ptr, page_size * page_count, start_time, timeout))
+ goto err_out;
+
+ /*
+ * verify that the right number of pages are merged:
+ * 1) if use_zero_pages is set to 1, empty pages are merged
+ * with the kernel zero page instead of with each other;
+ * 2) if use_zero_pages is set to 0, empty pages are not treated specially
+ * and merged as usual.
+ */
+ if (use_zero_pages && !assert_ksm_pages_count(0))
+ goto err_out;
+ else if (!use_zero_pages && !assert_ksm_pages_count(page_count))
+ goto err_out;
+
+ printf("OK\n");
+ munmap(map_ptr, page_size * page_count);
+ return KSFT_PASS;
+
+err_out:
+ printf("Not OK\n");
+ munmap(map_ptr, page_size * page_count);
+ return KSFT_FAIL;
+}
+
+static int get_next_mem_node(int node)
+{
+
+ long node_size;
+ int mem_node = 0;
+ int i, max_node = numa_max_node();
+
+ for (i = node + 1; i <= max_node + node; i++) {
+ mem_node = i % (max_node + 1);
+ node_size = numa_node_size(mem_node, NULL);
+ if (node_size > 0)
+ break;
+ }
+ return mem_node;
+}
+
+static int get_first_mem_node(void)
+{
+ return get_next_mem_node(numa_max_node());
+}
+
+static int check_ksm_numa_merge(int mapping, int prot, int timeout, bool merge_across_nodes,
+ size_t page_size)
+{
+ void *numa1_map_ptr, *numa2_map_ptr;
+ struct timespec start_time;
+ int page_count = 2;
+ int first_node;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ return KSFT_FAIL;
+ }
+
+ if (numa_available() < 0) {
+ perror("NUMA support not enabled");
+ return KSFT_SKIP;
+ }
+ if (numa_num_configured_nodes() <= 1) {
+ printf("At least 2 NUMA nodes must be available\n");
+ return KSFT_SKIP;
+ }
+ if (ksm_write_sysfs(KSM_FP("merge_across_nodes"), merge_across_nodes))
+ return KSFT_FAIL;
+
+ /* allocate 2 pages in 2 different NUMA nodes and fill them with the same data */
+ first_node = get_first_mem_node();
+ numa1_map_ptr = numa_alloc_onnode(page_size, first_node);
+ numa2_map_ptr = numa_alloc_onnode(page_size, get_next_mem_node(first_node));
+ if (!numa1_map_ptr || !numa2_map_ptr) {
+ perror("numa_alloc_onnode");
+ return KSFT_FAIL;
+ }
+
+ memset(numa1_map_ptr, '*', page_size);
+ memset(numa2_map_ptr, '*', page_size);
+
+ /* try to merge the pages */
+ if (ksm_merge_pages(numa1_map_ptr, page_size, start_time, timeout) ||
+ ksm_merge_pages(numa2_map_ptr, page_size, start_time, timeout))
+ goto err_out;
+
+ /*
+ * verify that the right number of pages are merged:
+ * 1) if merge_across_nodes was enabled, 2 duplicate pages will be merged;
+ * 2) if merge_across_nodes = 0, there must be 0 merged pages, since there is
+ * only 1 unique page in each node and they can't be shared.
+ */
+ if (merge_across_nodes && !assert_ksm_pages_count(page_count))
+ goto err_out;
+ else if (!merge_across_nodes && !assert_ksm_pages_count(0))
+ goto err_out;
+
+ numa_free(numa1_map_ptr, page_size);
+ numa_free(numa2_map_ptr, page_size);
+ printf("OK\n");
+ return KSFT_PASS;
+
+err_out:
+ numa_free(numa1_map_ptr, page_size);
+ numa_free(numa2_map_ptr, page_size);
+ printf("Not OK\n");
+ return KSFT_FAIL;
+}
+
+static int ksm_merge_hugepages_time(int mapping, int prot, int timeout, size_t map_size)
+{
+ void *map_ptr, *map_ptr_orig;
+ struct timespec start_time, end_time;
+ unsigned long scan_time_ns;
+ int pagemap_fd, n_normal_pages, n_huge_pages;
+
+ map_size *= MB;
+ size_t len = map_size;
+
+ len -= len % HPAGE_SIZE;
+ map_ptr_orig = mmap(NULL, len + HPAGE_SIZE, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE, -1, 0);
+ map_ptr = map_ptr_orig + HPAGE_SIZE - (uintptr_t)map_ptr_orig % HPAGE_SIZE;
+
+ if (map_ptr_orig == MAP_FAILED)
+ err(2, "initial mmap");
+
+ if (madvise(map_ptr, len + HPAGE_SIZE, MADV_HUGEPAGE))
+ err(2, "MADV_HUGEPAGE");
+
+ pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
+ if (pagemap_fd < 0)
+ err(2, "open pagemap");
+
+ n_normal_pages = 0;
+ n_huge_pages = 0;
+ for (void *p = map_ptr; p < map_ptr + len; p += HPAGE_SIZE) {
+ if (allocate_transhuge(p, pagemap_fd) < 0)
+ n_normal_pages++;
+ else
+ n_huge_pages++;
+ }
+ printf("Number of normal pages: %d\n", n_normal_pages);
+ printf("Number of huge pages: %d\n", n_huge_pages);
+
+ memset(map_ptr, '*', len);
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+ if (ksm_merge_pages(map_ptr, map_size, start_time, timeout))
+ goto err_out;
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+
+ scan_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +
+ (end_time.tv_nsec - start_time.tv_nsec);
+
+ printf("Total size: %lu MiB\n", map_size / MB);
+ printf("Total time: %ld.%09ld s\n", scan_time_ns / NSEC_PER_SEC,
+ scan_time_ns % NSEC_PER_SEC);
+ printf("Average speed: %.3f MiB/s\n", (map_size / MB) /
+ ((double)scan_time_ns / NSEC_PER_SEC));
+
+ munmap(map_ptr_orig, len + HPAGE_SIZE);
+ return KSFT_PASS;
+
+err_out:
+ printf("Not OK\n");
+ munmap(map_ptr_orig, len + HPAGE_SIZE);
+ return KSFT_FAIL;
+}
+
+static int ksm_merge_time(int mapping, int prot, int timeout, size_t map_size)
+{
+ void *map_ptr;
+ struct timespec start_time, end_time;
+ unsigned long scan_time_ns;
+
+ map_size *= MB;
+
+ map_ptr = allocate_memory(NULL, prot, mapping, '*', map_size);
+ if (!map_ptr)
+ return KSFT_FAIL;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+ if (ksm_merge_pages(map_ptr, map_size, start_time, timeout))
+ goto err_out;
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+
+ scan_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +
+ (end_time.tv_nsec - start_time.tv_nsec);
+
+ printf("Total size: %lu MiB\n", map_size / MB);
+ printf("Total time: %ld.%09ld s\n", scan_time_ns / NSEC_PER_SEC,
+ scan_time_ns % NSEC_PER_SEC);
+ printf("Average speed: %.3f MiB/s\n", (map_size / MB) /
+ ((double)scan_time_ns / NSEC_PER_SEC));
+
+ munmap(map_ptr, map_size);
+ return KSFT_PASS;
+
+err_out:
+ printf("Not OK\n");
+ munmap(map_ptr, map_size);
+ return KSFT_FAIL;
+}
+
+static int ksm_unmerge_time(int mapping, int prot, int timeout, size_t map_size)
+{
+ void *map_ptr;
+ struct timespec start_time, end_time;
+ unsigned long scan_time_ns;
+
+ map_size *= MB;
+
+ map_ptr = allocate_memory(NULL, prot, mapping, '*', map_size);
+ if (!map_ptr)
+ return KSFT_FAIL;
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+ if (ksm_merge_pages(map_ptr, map_size, start_time, timeout))
+ goto err_out;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+ if (ksm_unmerge_pages(map_ptr, map_size, start_time, timeout))
+ goto err_out;
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+
+ scan_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +
+ (end_time.tv_nsec - start_time.tv_nsec);
+
+ printf("Total size: %lu MiB\n", map_size / MB);
+ printf("Total time: %ld.%09ld s\n", scan_time_ns / NSEC_PER_SEC,
+ scan_time_ns % NSEC_PER_SEC);
+ printf("Average speed: %.3f MiB/s\n", (map_size / MB) /
+ ((double)scan_time_ns / NSEC_PER_SEC));
+
+ munmap(map_ptr, map_size);
+ return KSFT_PASS;
+
+err_out:
+ printf("Not OK\n");
+ munmap(map_ptr, map_size);
+ return KSFT_FAIL;
+}
+
+static int ksm_cow_time(int mapping, int prot, int timeout, size_t page_size)
+{
+ void *map_ptr;
+ struct timespec start_time, end_time;
+ unsigned long cow_time_ns;
+
+ /* page_count must be less than 2*page_size */
+ size_t page_count = 4000;
+
+ map_ptr = allocate_memory(NULL, prot, mapping, '*', page_size * page_count);
+ if (!map_ptr)
+ return KSFT_FAIL;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ return KSFT_FAIL;
+ }
+ for (size_t i = 0; i < page_count - 1; i = i + 2)
+ memset(map_ptr + page_size * i, '-', 1);
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {
+ perror("clock_gettime");
+ return KSFT_FAIL;
+ }
+
+ cow_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +
+ (end_time.tv_nsec - start_time.tv_nsec);
+
+ printf("Total size: %lu MiB\n\n", (page_size * page_count) / MB);
+ printf("Not merged pages:\n");
+ printf("Total time: %ld.%09ld s\n", cow_time_ns / NSEC_PER_SEC,
+ cow_time_ns % NSEC_PER_SEC);
+ printf("Average speed: %.3f MiB/s\n\n", ((page_size * (page_count / 2)) / MB) /
+ ((double)cow_time_ns / NSEC_PER_SEC));
+
+ /* Create 2000 pairs of duplicate pages */
+ for (size_t i = 0; i < page_count - 1; i = i + 2) {
+ memset(map_ptr + page_size * i, '+', i / 2 + 1);
+ memset(map_ptr + page_size * (i + 1), '+', i / 2 + 1);
+ }
+ if (ksm_merge_pages(map_ptr, page_size * page_count, start_time, timeout))
+ goto err_out;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &start_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+ for (size_t i = 0; i < page_count - 1; i = i + 2)
+ memset(map_ptr + page_size * i, '-', 1);
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &end_time)) {
+ perror("clock_gettime");
+ goto err_out;
+ }
+
+ cow_time_ns = (end_time.tv_sec - start_time.tv_sec) * NSEC_PER_SEC +
+ (end_time.tv_nsec - start_time.tv_nsec);
+
+ printf("Merged pages:\n");
+ printf("Total time: %ld.%09ld s\n", cow_time_ns / NSEC_PER_SEC,
+ cow_time_ns % NSEC_PER_SEC);
+ printf("Average speed: %.3f MiB/s\n", ((page_size * (page_count / 2)) / MB) /
+ ((double)cow_time_ns / NSEC_PER_SEC));
+
+ munmap(map_ptr, page_size * page_count);
+ return KSFT_PASS;
+
+err_out:
+ printf("Not OK\n");
+ munmap(map_ptr, page_size * page_count);
+ return KSFT_FAIL;
+}
+
+int main(int argc, char *argv[])
+{
+ int ret, opt;
+ int prot = 0;
+ int ksm_scan_limit_sec = KSM_SCAN_LIMIT_SEC_DEFAULT;
+ long page_count = KSM_PAGE_COUNT_DEFAULT;
+ size_t page_size = sysconf(_SC_PAGESIZE);
+ struct ksm_sysfs ksm_sysfs_old;
+ int test_name = CHECK_KSM_MERGE;
+ bool use_zero_pages = KSM_USE_ZERO_PAGES_DEFAULT;
+ bool merge_across_nodes = KSM_MERGE_ACROSS_NODES_DEFAULT;
+ long size_MB = 0;
+
+ while ((opt = getopt(argc, argv, "ha:p:l:z:m:s:MUZNPCHD")) != -1) {
+ switch (opt) {
+ case 'a':
+ prot = str_to_prot(optarg);
+ break;
+ case 'p':
+ page_count = atol(optarg);
+ if (page_count <= 0) {
+ printf("The number of pages must be greater than 0\n");
+ return KSFT_FAIL;
+ }
+ break;
+ case 'l':
+ ksm_scan_limit_sec = atoi(optarg);
+ if (ksm_scan_limit_sec <= 0) {
+ printf("Timeout value must be greater than 0\n");
+ return KSFT_FAIL;
+ }
+ break;
+ case 'h':
+ print_help();
+ break;
+ case 'z':
+ if (strcmp(optarg, "0") == 0)
+ use_zero_pages = 0;
+ else
+ use_zero_pages = 1;
+ break;
+ case 'm':
+ if (strcmp(optarg, "0") == 0)
+ merge_across_nodes = 0;
+ else
+ merge_across_nodes = 1;
+ break;
+ case 's':
+ size_MB = atoi(optarg);
+ if (size_MB <= 0) {
+ printf("Size must be greater than 0\n");
+ return KSFT_FAIL;
+ }
+ case 'M':
+ break;
+ case 'U':
+ test_name = CHECK_KSM_UNMERGE;
+ break;
+ case 'Z':
+ test_name = CHECK_KSM_ZERO_PAGE_MERGE;
+ break;
+ case 'N':
+ test_name = CHECK_KSM_NUMA_MERGE;
+ break;
+ case 'P':
+ test_name = KSM_MERGE_TIME;
+ break;
+ case 'H':
+ test_name = KSM_MERGE_TIME_HUGE_PAGES;
+ break;
+ case 'D':
+ test_name = KSM_UNMERGE_TIME;
+ break;
+ case 'C':
+ test_name = KSM_COW_TIME;
+ break;
+ default:
+ return KSFT_FAIL;
+ }
+ }
+
+ if (prot == 0)
+ prot = str_to_prot(KSM_PROT_STR_DEFAULT);
+
+ if (access(KSM_SYSFS_PATH, F_OK)) {
+ printf("Config KSM not enabled\n");
+ return KSFT_SKIP;
+ }
+
+ if (ksm_save_def(&ksm_sysfs_old)) {
+ printf("Cannot save default tunables\n");
+ return KSFT_FAIL;
+ }
+
+ if (ksm_write_sysfs(KSM_FP("run"), 2) ||
+ ksm_write_sysfs(KSM_FP("sleep_millisecs"), 0) ||
+ numa_available() ? 0 :
+ ksm_write_sysfs(KSM_FP("merge_across_nodes"), 1) ||
+ ksm_write_sysfs(KSM_FP("pages_to_scan"), page_count))
+ return KSFT_FAIL;
+
+ switch (test_name) {
+ case CHECK_KSM_MERGE:
+ ret = check_ksm_merge(MAP_PRIVATE | MAP_ANONYMOUS, prot, page_count,
+ ksm_scan_limit_sec, page_size);
+ break;
+ case CHECK_KSM_UNMERGE:
+ ret = check_ksm_unmerge(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec,
+ page_size);
+ break;
+ case CHECK_KSM_ZERO_PAGE_MERGE:
+ ret = check_ksm_zero_page_merge(MAP_PRIVATE | MAP_ANONYMOUS, prot, page_count,
+ ksm_scan_limit_sec, use_zero_pages, page_size);
+ break;
+ case CHECK_KSM_NUMA_MERGE:
+ ret = check_ksm_numa_merge(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec,
+ merge_across_nodes, page_size);
+ break;
+ case KSM_MERGE_TIME:
+ if (size_MB == 0) {
+ printf("Option '-s' is required.\n");
+ return KSFT_FAIL;
+ }
+ ret = ksm_merge_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec,
+ size_MB);
+ break;
+ case KSM_MERGE_TIME_HUGE_PAGES:
+ if (size_MB == 0) {
+ printf("Option '-s' is required.\n");
+ return KSFT_FAIL;
+ }
+ ret = ksm_merge_hugepages_time(MAP_PRIVATE | MAP_ANONYMOUS, prot,
+ ksm_scan_limit_sec, size_MB);
+ break;
+ case KSM_UNMERGE_TIME:
+ if (size_MB == 0) {
+ printf("Option '-s' is required.\n");
+ return KSFT_FAIL;
+ }
+ ret = ksm_unmerge_time(MAP_PRIVATE | MAP_ANONYMOUS, prot,
+ ksm_scan_limit_sec, size_MB);
+ break;
+ case KSM_COW_TIME:
+ ret = ksm_cow_time(MAP_PRIVATE | MAP_ANONYMOUS, prot, ksm_scan_limit_sec,
+ page_size);
+ break;
+ }
+
+ if (ksm_restore(&ksm_sysfs_old)) {
+ printf("Cannot restore default tunables\n");
+ return KSFT_FAIL;
+ }
+
+ return ret;
+}
diff --git a/tools/testing/selftests/mm/madv_populate.c b/tools/testing/selftests/mm/madv_populate.c
new file mode 100644
index 000000000000..262eae6b58f2
--- /dev/null
+++ b/tools/testing/selftests/mm/madv_populate.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MADV_POPULATE_READ and MADV_POPULATE_WRITE tests
+ *
+ * Copyright 2021, Red Hat, Inc.
+ *
+ * Author(s): David Hildenbrand <david@redhat.com>
+ */
+#define _GNU_SOURCE
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/mman.h>
+#include <sys/mman.h>
+
+#include "../kselftest.h"
+#include "vm_util.h"
+
+#ifndef MADV_POPULATE_READ
+#define MADV_POPULATE_READ 22
+#endif /* MADV_POPULATE_READ */
+#ifndef MADV_POPULATE_WRITE
+#define MADV_POPULATE_WRITE 23
+#endif /* MADV_POPULATE_WRITE */
+
+/*
+ * For now, we're using 2 MiB of private anonymous memory for all tests.
+ */
+#define SIZE (2 * 1024 * 1024)
+
+static size_t pagesize;
+
+static void sense_support(void)
+{
+ char *addr;
+ int ret;
+
+ addr = mmap(0, pagesize, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+ if (!addr)
+ ksft_exit_fail_msg("mmap failed\n");
+
+ ret = madvise(addr, pagesize, MADV_POPULATE_READ);
+ if (ret)
+ ksft_exit_skip("MADV_POPULATE_READ is not available\n");
+
+ ret = madvise(addr, pagesize, MADV_POPULATE_WRITE);
+ if (ret)
+ ksft_exit_skip("MADV_POPULATE_WRITE is not available\n");
+
+ munmap(addr, pagesize);
+}
+
+static void test_prot_read(void)
+{
+ char *addr;
+ int ret;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ addr = mmap(0, SIZE, PROT_READ, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+ if (addr == MAP_FAILED)
+ ksft_exit_fail_msg("mmap failed\n");
+
+ ret = madvise(addr, SIZE, MADV_POPULATE_READ);
+ ksft_test_result(!ret, "MADV_POPULATE_READ with PROT_READ\n");
+
+ ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
+ ksft_test_result(ret == -1 && errno == EINVAL,
+ "MADV_POPULATE_WRITE with PROT_READ\n");
+
+ munmap(addr, SIZE);
+}
+
+static void test_prot_write(void)
+{
+ char *addr;
+ int ret;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ addr = mmap(0, SIZE, PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+ if (addr == MAP_FAILED)
+ ksft_exit_fail_msg("mmap failed\n");
+
+ ret = madvise(addr, SIZE, MADV_POPULATE_READ);
+ ksft_test_result(ret == -1 && errno == EINVAL,
+ "MADV_POPULATE_READ with PROT_WRITE\n");
+
+ ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
+ ksft_test_result(!ret, "MADV_POPULATE_WRITE with PROT_WRITE\n");
+
+ munmap(addr, SIZE);
+}
+
+static void test_holes(void)
+{
+ char *addr;
+ int ret;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ addr = mmap(0, SIZE, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+ if (addr == MAP_FAILED)
+ ksft_exit_fail_msg("mmap failed\n");
+ ret = munmap(addr + pagesize, pagesize);
+ if (ret)
+ ksft_exit_fail_msg("munmap failed\n");
+
+ /* Hole in the middle */
+ ret = madvise(addr, SIZE, MADV_POPULATE_READ);
+ ksft_test_result(ret == -1 && errno == ENOMEM,
+ "MADV_POPULATE_READ with holes in the middle\n");
+ ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
+ ksft_test_result(ret == -1 && errno == ENOMEM,
+ "MADV_POPULATE_WRITE with holes in the middle\n");
+
+ /* Hole at end */
+ ret = madvise(addr, 2 * pagesize, MADV_POPULATE_READ);
+ ksft_test_result(ret == -1 && errno == ENOMEM,
+ "MADV_POPULATE_READ with holes at the end\n");
+ ret = madvise(addr, 2 * pagesize, MADV_POPULATE_WRITE);
+ ksft_test_result(ret == -1 && errno == ENOMEM,
+ "MADV_POPULATE_WRITE with holes at the end\n");
+
+ /* Hole at beginning */
+ ret = madvise(addr + pagesize, pagesize, MADV_POPULATE_READ);
+ ksft_test_result(ret == -1 && errno == ENOMEM,
+ "MADV_POPULATE_READ with holes at the beginning\n");
+ ret = madvise(addr + pagesize, pagesize, MADV_POPULATE_WRITE);
+ ksft_test_result(ret == -1 && errno == ENOMEM,
+ "MADV_POPULATE_WRITE with holes at the beginning\n");
+
+ munmap(addr, SIZE);
+}
+
+static bool range_is_populated(char *start, ssize_t size)
+{
+ int fd = open("/proc/self/pagemap", O_RDONLY);
+ bool ret = true;
+
+ if (fd < 0)
+ ksft_exit_fail_msg("opening pagemap failed\n");
+ for (; size > 0 && ret; size -= pagesize, start += pagesize)
+ if (!pagemap_is_populated(fd, start))
+ ret = false;
+ close(fd);
+ return ret;
+}
+
+static bool range_is_not_populated(char *start, ssize_t size)
+{
+ int fd = open("/proc/self/pagemap", O_RDONLY);
+ bool ret = true;
+
+ if (fd < 0)
+ ksft_exit_fail_msg("opening pagemap failed\n");
+ for (; size > 0 && ret; size -= pagesize, start += pagesize)
+ if (pagemap_is_populated(fd, start))
+ ret = false;
+ close(fd);
+ return ret;
+}
+
+static void test_populate_read(void)
+{
+ char *addr;
+ int ret;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ addr = mmap(0, SIZE, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+ if (addr == MAP_FAILED)
+ ksft_exit_fail_msg("mmap failed\n");
+ ksft_test_result(range_is_not_populated(addr, SIZE),
+ "range initially not populated\n");
+
+ ret = madvise(addr, SIZE, MADV_POPULATE_READ);
+ ksft_test_result(!ret, "MADV_POPULATE_READ\n");
+ ksft_test_result(range_is_populated(addr, SIZE),
+ "range is populated\n");
+
+ munmap(addr, SIZE);
+}
+
+static void test_populate_write(void)
+{
+ char *addr;
+ int ret;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ addr = mmap(0, SIZE, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+ if (addr == MAP_FAILED)
+ ksft_exit_fail_msg("mmap failed\n");
+ ksft_test_result(range_is_not_populated(addr, SIZE),
+ "range initially not populated\n");
+
+ ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
+ ksft_test_result(!ret, "MADV_POPULATE_WRITE\n");
+ ksft_test_result(range_is_populated(addr, SIZE),
+ "range is populated\n");
+
+ munmap(addr, SIZE);
+}
+
+static bool range_is_softdirty(char *start, ssize_t size)
+{
+ int fd = open("/proc/self/pagemap", O_RDONLY);
+ bool ret = true;
+
+ if (fd < 0)
+ ksft_exit_fail_msg("opening pagemap failed\n");
+ for (; size > 0 && ret; size -= pagesize, start += pagesize)
+ if (!pagemap_is_softdirty(fd, start))
+ ret = false;
+ close(fd);
+ return ret;
+}
+
+static bool range_is_not_softdirty(char *start, ssize_t size)
+{
+ int fd = open("/proc/self/pagemap", O_RDONLY);
+ bool ret = true;
+
+ if (fd < 0)
+ ksft_exit_fail_msg("opening pagemap failed\n");
+ for (; size > 0 && ret; size -= pagesize, start += pagesize)
+ if (pagemap_is_softdirty(fd, start))
+ ret = false;
+ close(fd);
+ return ret;
+}
+
+static void test_softdirty(void)
+{
+ char *addr;
+ int ret;
+
+ ksft_print_msg("[RUN] %s\n", __func__);
+
+ addr = mmap(0, SIZE, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
+ if (addr == MAP_FAILED)
+ ksft_exit_fail_msg("mmap failed\n");
+
+ /* Clear any softdirty bits. */
+ clear_softdirty();
+ ksft_test_result(range_is_not_softdirty(addr, SIZE),
+ "range is not softdirty\n");
+
+ /* Populating READ should set softdirty. */
+ ret = madvise(addr, SIZE, MADV_POPULATE_READ);
+ ksft_test_result(!ret, "MADV_POPULATE_READ\n");
+ ksft_test_result(range_is_not_softdirty(addr, SIZE),
+ "range is not softdirty\n");
+
+ /* Populating WRITE should set softdirty. */
+ ret = madvise(addr, SIZE, MADV_POPULATE_WRITE);
+ ksft_test_result(!ret, "MADV_POPULATE_WRITE\n");
+ ksft_test_result(range_is_softdirty(addr, SIZE),
+ "range is softdirty\n");
+
+ munmap(addr, SIZE);
+}
+
+int main(int argc, char **argv)
+{
+ int err;
+
+ pagesize = getpagesize();
+
+ ksft_print_header();
+ ksft_set_plan(21);
+
+ sense_support();
+ test_prot_read();
+ test_prot_write();
+ test_holes();
+ test_populate_read();
+ test_populate_write();
+ test_softdirty();
+
+ err = ksft_get_fail_cnt();
+ if (err)
+ ksft_exit_fail_msg("%d out of %d tests failed\n",
+ err, ksft_test_num());
+ return ksft_exit_pass();
+}
diff --git a/tools/testing/selftests/mm/map_fixed_noreplace.c b/tools/testing/selftests/mm/map_fixed_noreplace.c
new file mode 100644
index 000000000000..eed44322d1a6
--- /dev/null
+++ b/tools/testing/selftests/mm/map_fixed_noreplace.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Test that MAP_FIXED_NOREPLACE works.
+ *
+ * Copyright 2018, Jann Horn <jannh@google.com>
+ * Copyright 2018, Michael Ellerman, IBM Corporation.
+ */
+
+#include <sys/mman.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#ifndef MAP_FIXED_NOREPLACE
+#define MAP_FIXED_NOREPLACE 0x100000
+#endif
+
+static void dump_maps(void)
+{
+ char cmd[32];
+
+ snprintf(cmd, sizeof(cmd), "cat /proc/%d/maps", getpid());
+ system(cmd);
+}
+
+static unsigned long find_base_addr(unsigned long size)
+{
+ void *addr;
+ unsigned long flags;
+
+ flags = MAP_PRIVATE | MAP_ANONYMOUS;
+ addr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
+ if (addr == MAP_FAILED) {
+ printf("Error: couldn't map the space we need for the test\n");
+ return 0;
+ }
+
+ if (munmap(addr, size) != 0) {
+ printf("Error: couldn't map the space we need for the test\n");
+ return 0;
+ }
+ return (unsigned long)addr;
+}
+
+int main(void)
+{
+ unsigned long base_addr;
+ unsigned long flags, addr, size, page_size;
+ char *p;
+
+ page_size = sysconf(_SC_PAGE_SIZE);
+
+ //let's find a base addr that is free before we start the tests
+ size = 5 * page_size;
+ base_addr = find_base_addr(size);
+ if (!base_addr) {
+ printf("Error: couldn't map the space we need for the test\n");
+ return 1;
+ }
+
+ flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED_NOREPLACE;
+
+ // Check we can map all the areas we need below
+ errno = 0;
+ addr = base_addr;
+ size = 5 * page_size;
+ p = mmap((void *)addr, size, PROT_NONE, flags, -1, 0);
+
+ printf("mmap() @ 0x%lx-0x%lx p=%p result=%m\n", addr, addr + size, p);
+
+ if (p == MAP_FAILED) {
+ dump_maps();
+ printf("Error: couldn't map the space we need for the test\n");
+ return 1;
+ }
+
+ errno = 0;
+ if (munmap((void *)addr, 5 * page_size) != 0) {
+ dump_maps();
+ printf("Error: munmap failed!?\n");
+ return 1;
+ }
+ printf("unmap() successful\n");
+
+ errno = 0;
+ addr = base_addr + page_size;
+ size = 3 * page_size;
+ p = mmap((void *)addr, size, PROT_NONE, flags, -1, 0);
+ printf("mmap() @ 0x%lx-0x%lx p=%p result=%m\n", addr, addr + size, p);
+
+ if (p == MAP_FAILED) {
+ dump_maps();
+ printf("Error: first mmap() failed unexpectedly\n");
+ return 1;
+ }
+
+ /*
+ * Exact same mapping again:
+ * base | free | new
+ * +1 | mapped | new
+ * +2 | mapped | new
+ * +3 | mapped | new
+ * +4 | free | new
+ */
+ errno = 0;
+ addr = base_addr;
+ size = 5 * page_size;
+ p = mmap((void *)addr, size, PROT_NONE, flags, -1, 0);
+ printf("mmap() @ 0x%lx-0x%lx p=%p result=%m\n", addr, addr + size, p);
+
+ if (p != MAP_FAILED) {
+ dump_maps();
+ printf("Error:1: mmap() succeeded when it shouldn't have\n");
+ return 1;
+ }
+
+ /*
+ * Second mapping contained within first:
+ *
+ * base | free |
+ * +1 | mapped |
+ * +2 | mapped | new
+ * +3 | mapped |
+ * +4 | free |
+ */
+ errno = 0;
+ addr = base_addr + (2 * page_size);
+ size = page_size;
+ p = mmap((void *)addr, size, PROT_NONE, flags, -1, 0);
+ printf("mmap() @ 0x%lx-0x%lx p=%p result=%m\n", addr, addr + size, p);
+
+ if (p != MAP_FAILED) {
+ dump_maps();
+ printf("Error:2: mmap() succeeded when it shouldn't have\n");
+ return 1;
+ }
+
+ /*
+ * Overlap end of existing mapping:
+ * base | free |
+ * +1 | mapped |
+ * +2 | mapped |
+ * +3 | mapped | new
+ * +4 | free | new
+ */
+ errno = 0;
+ addr = base_addr + (3 * page_size);
+ size = 2 * page_size;
+ p = mmap((void *)addr, size, PROT_NONE, flags, -1, 0);
+ printf("mmap() @ 0x%lx-0x%lx p=%p result=%m\n", addr, addr + size, p);
+
+ if (p != MAP_FAILED) {
+ dump_maps();
+ printf("Error:3: mmap() succeeded when it shouldn't have\n");
+ return 1;
+ }
+
+ /*
+ * Overlap start of existing mapping:
+ * base | free | new
+ * +1 | mapped | new
+ * +2 | mapped |
+ * +3 | mapped |
+ * +4 | free |
+ */
+ errno = 0;
+ addr = base_addr;
+ size = 2 * page_size;
+ p = mmap((void *)addr, size, PROT_NONE, flags, -1, 0);
+ printf("mmap() @ 0x%lx-0x%lx p=%p result=%m\n", addr, addr + size, p);
+
+ if (p != MAP_FAILED) {
+ dump_maps();
+ printf("Error:4: mmap() succeeded when it shouldn't have\n");
+ return 1;
+ }
+
+ /*
+ * Adjacent to start of existing mapping:
+ * base | free | new
+ * +1 | mapped |
+ * +2 | mapped |
+ * +3 | mapped |
+ * +4 | free |
+ */
+ errno = 0;
+ addr = base_addr;
+ size = page_size;
+ p = mmap((void *)addr, size, PROT_NONE, flags, -1, 0);
+ printf("mmap() @ 0x%lx-0x%lx p=%p result=%m\n", addr, addr + size, p);
+
+ if (p == MAP_FAILED) {
+ dump_maps();
+ printf("Error:5: mmap() failed when it shouldn't have\n");
+ return 1;
+ }
+
+ /*
+ * Adjacent to end of existing mapping:
+ * base | free |
+ * +1 | mapped |
+ * +2 | mapped |
+ * +3 | mapped |
+ * +4 | free | new
+ */
+ errno = 0;
+ addr = base_addr + (4 * page_size);
+ size = page_size;
+ p = mmap((void *)addr, size, PROT_NONE, flags, -1, 0);
+ printf("mmap() @ 0x%lx-0x%lx p=%p result=%m\n", addr, addr + size, p);
+
+ if (p == MAP_FAILED) {
+ dump_maps();
+ printf("Error:6: mmap() failed when it shouldn't have\n");
+ return 1;
+ }
+
+ addr = base_addr;
+ size = 5 * page_size;
+ if (munmap((void *)addr, size) != 0) {
+ dump_maps();
+ printf("Error: munmap failed!?\n");
+ return 1;
+ }
+ printf("unmap() successful\n");
+
+ printf("OK\n");
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/map_hugetlb.c b/tools/testing/selftests/mm/map_hugetlb.c
new file mode 100644
index 000000000000..312889edb84a
--- /dev/null
+++ b/tools/testing/selftests/mm/map_hugetlb.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Example of using hugepage memory in a user application using the mmap
+ * system call with MAP_HUGETLB flag. Before running this program make
+ * sure the administrator has allocated enough default sized huge pages
+ * to cover the 256 MB allocation.
+ *
+ * For ia64 architecture, Linux kernel reserves Region number 4 for hugepages.
+ * That means the addresses starting with 0x800000... will need to be
+ * specified. Specifying a fixed address is not required on ppc64, i386
+ * or x86_64.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+
+#define LENGTH (256UL*1024*1024)
+#define PROTECTION (PROT_READ | PROT_WRITE)
+
+#ifndef MAP_HUGETLB
+#define MAP_HUGETLB 0x40000 /* arch specific */
+#endif
+
+#ifndef MAP_HUGE_SHIFT
+#define MAP_HUGE_SHIFT 26
+#endif
+
+#ifndef MAP_HUGE_MASK
+#define MAP_HUGE_MASK 0x3f
+#endif
+
+/* Only ia64 requires this */
+#ifdef __ia64__
+#define ADDR (void *)(0x8000000000000000UL)
+#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_FIXED)
+#else
+#define ADDR (void *)(0x0UL)
+#define FLAGS (MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB)
+#endif
+
+static void check_bytes(char *addr)
+{
+ printf("First hex is %x\n", *((unsigned int *)addr));
+}
+
+static void write_bytes(char *addr, size_t length)
+{
+ unsigned long i;
+
+ for (i = 0; i < length; i++)
+ *(addr + i) = (char)i;
+}
+
+static int read_bytes(char *addr, size_t length)
+{
+ unsigned long i;
+
+ check_bytes(addr);
+ for (i = 0; i < length; i++)
+ if (*(addr + i) != (char)i) {
+ printf("Mismatch at %lu\n", i);
+ return 1;
+ }
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ void *addr;
+ int ret;
+ size_t length = LENGTH;
+ int flags = FLAGS;
+ int shift = 0;
+
+ if (argc > 1)
+ length = atol(argv[1]) << 20;
+ if (argc > 2) {
+ shift = atoi(argv[2]);
+ if (shift)
+ flags |= (shift & MAP_HUGE_MASK) << MAP_HUGE_SHIFT;
+ }
+
+ if (shift)
+ printf("%u kB hugepages\n", 1 << (shift - 10));
+ else
+ printf("Default size hugepages\n");
+ printf("Mapping %lu Mbytes\n", (unsigned long)length >> 20);
+
+ addr = mmap(ADDR, length, PROTECTION, flags, -1, 0);
+ if (addr == MAP_FAILED) {
+ perror("mmap");
+ exit(1);
+ }
+
+ printf("Returned address is %p\n", addr);
+ check_bytes(addr);
+ write_bytes(addr, length);
+ ret = read_bytes(addr, length);
+
+ /* munmap() length of MAP_HUGETLB memory must be hugepage aligned */
+ if (munmap(addr, length)) {
+ perror("munmap");
+ exit(1);
+ }
+
+ return ret;
+}
diff --git a/tools/testing/selftests/mm/map_populate.c b/tools/testing/selftests/mm/map_populate.c
new file mode 100644
index 000000000000..6b8aeaa0bf7a
--- /dev/null
+++ b/tools/testing/selftests/mm/map_populate.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 Dmitry Safonov, Arista Networks
+ *
+ * MAP_POPULATE | MAP_PRIVATE should COW VMA pages.
+ */
+
+#define _GNU_SOURCE
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifndef MMAP_SZ
+#define MMAP_SZ 4096
+#endif
+
+#define BUG_ON(condition, description) \
+ do { \
+ if (condition) { \
+ fprintf(stderr, "[FAIL]\t%s:%d\t%s:%s\n", __func__, \
+ __LINE__, (description), strerror(errno)); \
+ exit(1); \
+ } \
+ } while (0)
+
+static int parent_f(int sock, unsigned long *smap, int child)
+{
+ int status, ret;
+
+ ret = read(sock, &status, sizeof(int));
+ BUG_ON(ret <= 0, "read(sock)");
+
+ *smap = 0x22222BAD;
+ ret = msync(smap, MMAP_SZ, MS_SYNC);
+ BUG_ON(ret, "msync()");
+
+ ret = write(sock, &status, sizeof(int));
+ BUG_ON(ret <= 0, "write(sock)");
+
+ waitpid(child, &status, 0);
+ BUG_ON(!WIFEXITED(status), "child in unexpected state");
+
+ return WEXITSTATUS(status);
+}
+
+static int child_f(int sock, unsigned long *smap, int fd)
+{
+ int ret, buf = 0;
+
+ smap = mmap(0, MMAP_SZ, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_POPULATE, fd, 0);
+ BUG_ON(smap == MAP_FAILED, "mmap()");
+
+ BUG_ON(*smap != 0xdeadbabe, "MAP_PRIVATE | MAP_POPULATE changed file");
+
+ ret = write(sock, &buf, sizeof(int));
+ BUG_ON(ret <= 0, "write(sock)");
+
+ ret = read(sock, &buf, sizeof(int));
+ BUG_ON(ret <= 0, "read(sock)");
+
+ BUG_ON(*smap == 0x22222BAD, "MAP_POPULATE didn't COW private page");
+ BUG_ON(*smap != 0xdeadbabe, "mapping was corrupted");
+
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ int sock[2], child, ret;
+ FILE *ftmp;
+ unsigned long *smap;
+
+ ftmp = tmpfile();
+ BUG_ON(ftmp == 0, "tmpfile()");
+
+ ret = ftruncate(fileno(ftmp), MMAP_SZ);
+ BUG_ON(ret, "ftruncate()");
+
+ smap = mmap(0, MMAP_SZ, PROT_READ | PROT_WRITE,
+ MAP_SHARED, fileno(ftmp), 0);
+ BUG_ON(smap == MAP_FAILED, "mmap()");
+
+ *smap = 0xdeadbabe;
+ /* Probably unnecessary, but let it be. */
+ ret = msync(smap, MMAP_SZ, MS_SYNC);
+ BUG_ON(ret, "msync()");
+
+ ret = socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sock);
+ BUG_ON(ret, "socketpair()");
+
+ child = fork();
+ BUG_ON(child == -1, "fork()");
+
+ if (child) {
+ ret = close(sock[0]);
+ BUG_ON(ret, "close()");
+
+ return parent_f(sock[1], smap, child);
+ }
+
+ ret = close(sock[1]);
+ BUG_ON(ret, "close()");
+
+ return child_f(sock[0], smap, fileno(ftmp));
+}
diff --git a/tools/testing/selftests/mm/mdwe_test.c b/tools/testing/selftests/mm/mdwe_test.c
new file mode 100644
index 000000000000..f466a099f1bf
--- /dev/null
+++ b/tools/testing/selftests/mm/mdwe_test.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#ifdef __aarch64__
+#include <asm/hwcap.h>
+#endif
+
+#include <linux/mman.h>
+#include <linux/prctl.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/auxv.h>
+#include <sys/prctl.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "../kselftest_harness.h"
+
+#ifndef __aarch64__
+# define PROT_BTI 0
+#endif
+
+TEST(prctl_flags)
+{
+ EXPECT_LT(prctl(PR_SET_MDWE, 7L, 0L, 0L, 0L), 0);
+ EXPECT_LT(prctl(PR_SET_MDWE, 0L, 7L, 0L, 0L), 0);
+ EXPECT_LT(prctl(PR_SET_MDWE, 0L, 0L, 7L, 0L), 0);
+ EXPECT_LT(prctl(PR_SET_MDWE, 0L, 0L, 0L, 7L), 0);
+
+ EXPECT_LT(prctl(PR_GET_MDWE, 7L, 0L, 0L, 0L), 0);
+ EXPECT_LT(prctl(PR_GET_MDWE, 0L, 7L, 0L, 0L), 0);
+ EXPECT_LT(prctl(PR_GET_MDWE, 0L, 0L, 7L, 0L), 0);
+ EXPECT_LT(prctl(PR_GET_MDWE, 0L, 0L, 0L, 7L), 0);
+}
+
+FIXTURE(mdwe)
+{
+ void *p;
+ int flags;
+ size_t size;
+ pid_t pid;
+};
+
+FIXTURE_VARIANT(mdwe)
+{
+ bool enabled;
+ bool forked;
+};
+
+FIXTURE_VARIANT_ADD(mdwe, stock)
+{
+ .enabled = false,
+ .forked = false,
+};
+
+FIXTURE_VARIANT_ADD(mdwe, enabled)
+{
+ .enabled = true,
+ .forked = false,
+};
+
+FIXTURE_VARIANT_ADD(mdwe, forked)
+{
+ .enabled = true,
+ .forked = true,
+};
+
+FIXTURE_SETUP(mdwe)
+{
+ int ret, status;
+
+ self->p = NULL;
+ self->flags = MAP_SHARED | MAP_ANONYMOUS;
+ self->size = getpagesize();
+
+ if (!variant->enabled)
+ return;
+
+ ret = prctl(PR_SET_MDWE, PR_MDWE_REFUSE_EXEC_GAIN, 0L, 0L, 0L);
+ ASSERT_EQ(ret, 0) {
+ TH_LOG("PR_SET_MDWE failed or unsupported");
+ }
+
+ ret = prctl(PR_GET_MDWE, 0L, 0L, 0L, 0L);
+ ASSERT_EQ(ret, 1);
+
+ if (variant->forked) {
+ self->pid = fork();
+ ASSERT_GE(self->pid, 0) {
+ TH_LOG("fork failed\n");
+ }
+
+ if (self->pid > 0) {
+ ret = waitpid(self->pid, &status, 0);
+ ASSERT_TRUE(WIFEXITED(status));
+ exit(WEXITSTATUS(status));
+ }
+ }
+}
+
+FIXTURE_TEARDOWN(mdwe)
+{
+ if (self->p && self->p != MAP_FAILED)
+ munmap(self->p, self->size);
+}
+
+TEST_F(mdwe, mmap_READ_EXEC)
+{
+ self->p = mmap(NULL, self->size, PROT_READ | PROT_EXEC, self->flags, 0, 0);
+ EXPECT_NE(self->p, MAP_FAILED);
+}
+
+TEST_F(mdwe, mmap_WRITE_EXEC)
+{
+ self->p = mmap(NULL, self->size, PROT_WRITE | PROT_EXEC, self->flags, 0, 0);
+ if (variant->enabled) {
+ EXPECT_EQ(self->p, MAP_FAILED);
+ } else {
+ EXPECT_NE(self->p, MAP_FAILED);
+ }
+}
+
+TEST_F(mdwe, mprotect_stay_EXEC)
+{
+ int ret;
+
+ self->p = mmap(NULL, self->size, PROT_READ | PROT_EXEC, self->flags, 0, 0);
+ ASSERT_NE(self->p, MAP_FAILED);
+
+ ret = mprotect(self->p, self->size, PROT_READ | PROT_EXEC);
+ EXPECT_EQ(ret, 0);
+}
+
+TEST_F(mdwe, mprotect_add_EXEC)
+{
+ int ret;
+
+ self->p = mmap(NULL, self->size, PROT_READ, self->flags, 0, 0);
+ ASSERT_NE(self->p, MAP_FAILED);
+
+ ret = mprotect(self->p, self->size, PROT_READ | PROT_EXEC);
+ if (variant->enabled) {
+ EXPECT_LT(ret, 0);
+ } else {
+ EXPECT_EQ(ret, 0);
+ }
+}
+
+TEST_F(mdwe, mprotect_WRITE_EXEC)
+{
+ int ret;
+
+ self->p = mmap(NULL, self->size, PROT_WRITE, self->flags, 0, 0);
+ ASSERT_NE(self->p, MAP_FAILED);
+
+ ret = mprotect(self->p, self->size, PROT_WRITE | PROT_EXEC);
+ if (variant->enabled) {
+ EXPECT_LT(ret, 0);
+ } else {
+ EXPECT_EQ(ret, 0);
+ }
+}
+
+TEST_F(mdwe, mmap_FIXED)
+{
+ void *p, *p2;
+
+ p2 = mmap(NULL, self->size, PROT_READ | PROT_EXEC, self->flags, 0, 0);
+ self->p = mmap(NULL, self->size, PROT_READ, self->flags, 0, 0);
+ ASSERT_NE(self->p, MAP_FAILED);
+
+ p = mmap(self->p + self->size, self->size, PROT_READ | PROT_EXEC,
+ self->flags | MAP_FIXED, 0, 0);
+ if (variant->enabled) {
+ EXPECT_EQ(p, MAP_FAILED);
+ } else {
+ EXPECT_EQ(p, self->p);
+ }
+}
+
+TEST_F(mdwe, arm64_BTI)
+{
+ int ret;
+
+#ifdef __aarch64__
+ if (!(getauxval(AT_HWCAP2) & HWCAP2_BTI))
+#endif
+ SKIP(return, "HWCAP2_BTI not supported");
+
+ self->p = mmap(NULL, self->size, PROT_EXEC, self->flags, 0, 0);
+ ASSERT_NE(self->p, MAP_FAILED);
+
+ ret = mprotect(self->p, self->size, PROT_EXEC | PROT_BTI);
+ EXPECT_EQ(ret, 0);
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/mm/memfd_secret.c b/tools/testing/selftests/mm/memfd_secret.c
new file mode 100644
index 000000000000..957b9e18c729
--- /dev/null
+++ b/tools/testing/selftests/mm/memfd_secret.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright IBM Corporation, 2021
+ *
+ * Author: Mike Rapoport <rppt@linux.ibm.com>
+ */
+
+#define _GNU_SOURCE
+#include <sys/uio.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <sys/ptrace.h>
+#include <sys/syscall.h>
+#include <sys/resource.h>
+#include <sys/capability.h>
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdio.h>
+
+#include "../kselftest.h"
+
+#define fail(fmt, ...) ksft_test_result_fail(fmt, ##__VA_ARGS__)
+#define pass(fmt, ...) ksft_test_result_pass(fmt, ##__VA_ARGS__)
+#define skip(fmt, ...) ksft_test_result_skip(fmt, ##__VA_ARGS__)
+
+#ifdef __NR_memfd_secret
+
+#define PATTERN 0x55
+
+static const int prot = PROT_READ | PROT_WRITE;
+static const int mode = MAP_SHARED;
+
+static unsigned long page_size;
+static unsigned long mlock_limit_cur;
+static unsigned long mlock_limit_max;
+
+static int memfd_secret(unsigned int flags)
+{
+ return syscall(__NR_memfd_secret, flags);
+}
+
+static void test_file_apis(int fd)
+{
+ char buf[64];
+
+ if ((read(fd, buf, sizeof(buf)) >= 0) ||
+ (write(fd, buf, sizeof(buf)) >= 0) ||
+ (pread(fd, buf, sizeof(buf), 0) >= 0) ||
+ (pwrite(fd, buf, sizeof(buf), 0) >= 0))
+ fail("unexpected file IO\n");
+ else
+ pass("file IO is blocked as expected\n");
+}
+
+static void test_mlock_limit(int fd)
+{
+ size_t len;
+ char *mem;
+
+ len = mlock_limit_cur;
+ mem = mmap(NULL, len, prot, mode, fd, 0);
+ if (mem == MAP_FAILED) {
+ fail("unable to mmap secret memory\n");
+ return;
+ }
+ munmap(mem, len);
+
+ len = mlock_limit_max * 2;
+ mem = mmap(NULL, len, prot, mode, fd, 0);
+ if (mem != MAP_FAILED) {
+ fail("unexpected mlock limit violation\n");
+ munmap(mem, len);
+ return;
+ }
+
+ pass("mlock limit is respected\n");
+}
+
+static void try_process_vm_read(int fd, int pipefd[2])
+{
+ struct iovec liov, riov;
+ char buf[64];
+ char *mem;
+
+ if (read(pipefd[0], &mem, sizeof(mem)) < 0) {
+ fail("pipe write: %s\n", strerror(errno));
+ exit(KSFT_FAIL);
+ }
+
+ liov.iov_len = riov.iov_len = sizeof(buf);
+ liov.iov_base = buf;
+ riov.iov_base = mem;
+
+ if (process_vm_readv(getppid(), &liov, 1, &riov, 1, 0) < 0) {
+ if (errno == ENOSYS)
+ exit(KSFT_SKIP);
+ exit(KSFT_PASS);
+ }
+
+ exit(KSFT_FAIL);
+}
+
+static void try_ptrace(int fd, int pipefd[2])
+{
+ pid_t ppid = getppid();
+ int status;
+ char *mem;
+ long ret;
+
+ if (read(pipefd[0], &mem, sizeof(mem)) < 0) {
+ perror("pipe write");
+ exit(KSFT_FAIL);
+ }
+
+ ret = ptrace(PTRACE_ATTACH, ppid, 0, 0);
+ if (ret) {
+ perror("ptrace_attach");
+ exit(KSFT_FAIL);
+ }
+
+ ret = waitpid(ppid, &status, WUNTRACED);
+ if ((ret != ppid) || !(WIFSTOPPED(status))) {
+ fprintf(stderr, "weird waitppid result %ld stat %x\n",
+ ret, status);
+ exit(KSFT_FAIL);
+ }
+
+ if (ptrace(PTRACE_PEEKDATA, ppid, mem, 0))
+ exit(KSFT_PASS);
+
+ exit(KSFT_FAIL);
+}
+
+static void check_child_status(pid_t pid, const char *name)
+{
+ int status;
+
+ waitpid(pid, &status, 0);
+
+ if (WIFEXITED(status) && WEXITSTATUS(status) == KSFT_SKIP) {
+ skip("%s is not supported\n", name);
+ return;
+ }
+
+ if ((WIFEXITED(status) && WEXITSTATUS(status) == KSFT_PASS) ||
+ WIFSIGNALED(status)) {
+ pass("%s is blocked as expected\n", name);
+ return;
+ }
+
+ fail("%s: unexpected memory access\n", name);
+}
+
+static void test_remote_access(int fd, const char *name,
+ void (*func)(int fd, int pipefd[2]))
+{
+ int pipefd[2];
+ pid_t pid;
+ char *mem;
+
+ if (pipe(pipefd)) {
+ fail("pipe failed: %s\n", strerror(errno));
+ return;
+ }
+
+ pid = fork();
+ if (pid < 0) {
+ fail("fork failed: %s\n", strerror(errno));
+ return;
+ }
+
+ if (pid == 0) {
+ func(fd, pipefd);
+ return;
+ }
+
+ mem = mmap(NULL, page_size, prot, mode, fd, 0);
+ if (mem == MAP_FAILED) {
+ fail("Unable to mmap secret memory\n");
+ return;
+ }
+
+ ftruncate(fd, page_size);
+ memset(mem, PATTERN, page_size);
+
+ if (write(pipefd[1], &mem, sizeof(mem)) < 0) {
+ fail("pipe write: %s\n", strerror(errno));
+ return;
+ }
+
+ check_child_status(pid, name);
+}
+
+static void test_process_vm_read(int fd)
+{
+ test_remote_access(fd, "process_vm_read", try_process_vm_read);
+}
+
+static void test_ptrace(int fd)
+{
+ test_remote_access(fd, "ptrace", try_ptrace);
+}
+
+static int set_cap_limits(rlim_t max)
+{
+ struct rlimit new;
+ cap_t cap = cap_init();
+
+ new.rlim_cur = max;
+ new.rlim_max = max;
+ if (setrlimit(RLIMIT_MEMLOCK, &new)) {
+ perror("setrlimit() returns error");
+ return -1;
+ }
+
+ /* drop capabilities including CAP_IPC_LOCK */
+ if (cap_set_proc(cap)) {
+ perror("cap_set_proc() returns error");
+ return -2;
+ }
+
+ return 0;
+}
+
+static void prepare(void)
+{
+ struct rlimit rlim;
+
+ page_size = sysconf(_SC_PAGE_SIZE);
+ if (!page_size)
+ ksft_exit_fail_msg("Failed to get page size %s\n",
+ strerror(errno));
+
+ if (getrlimit(RLIMIT_MEMLOCK, &rlim))
+ ksft_exit_fail_msg("Unable to detect mlock limit: %s\n",
+ strerror(errno));
+
+ mlock_limit_cur = rlim.rlim_cur;
+ mlock_limit_max = rlim.rlim_max;
+
+ printf("page_size: %ld, mlock.soft: %ld, mlock.hard: %ld\n",
+ page_size, mlock_limit_cur, mlock_limit_max);
+
+ if (page_size > mlock_limit_cur)
+ mlock_limit_cur = page_size;
+ if (page_size > mlock_limit_max)
+ mlock_limit_max = page_size;
+
+ if (set_cap_limits(mlock_limit_max))
+ ksft_exit_fail_msg("Unable to set mlock limit: %s\n",
+ strerror(errno));
+}
+
+#define NUM_TESTS 4
+
+int main(int argc, char *argv[])
+{
+ int fd;
+
+ prepare();
+
+ ksft_print_header();
+ ksft_set_plan(NUM_TESTS);
+
+ fd = memfd_secret(0);
+ if (fd < 0) {
+ if (errno == ENOSYS)
+ ksft_exit_skip("memfd_secret is not supported\n");
+ else
+ ksft_exit_fail_msg("memfd_secret failed: %s\n",
+ strerror(errno));
+ }
+
+ test_mlock_limit(fd);
+ test_file_apis(fd);
+ test_process_vm_read(fd);
+ test_ptrace(fd);
+
+ close(fd);
+
+ ksft_finished();
+}
+
+#else /* __NR_memfd_secret */
+
+int main(int argc, char *argv[])
+{
+ printf("skip: skipping memfd_secret test (missing __NR_memfd_secret)\n");
+ return KSFT_SKIP;
+}
+
+#endif /* __NR_memfd_secret */
diff --git a/tools/testing/selftests/mm/migration.c b/tools/testing/selftests/mm/migration.c
new file mode 100644
index 000000000000..1cec8425e3ca
--- /dev/null
+++ b/tools/testing/selftests/mm/migration.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * The main purpose of the tests here is to exercise the migration entry code
+ * paths in the kernel.
+ */
+
+#include "../kselftest_harness.h"
+#include <strings.h>
+#include <pthread.h>
+#include <numa.h>
+#include <numaif.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <time.h>
+
+#define TWOMEG (2<<20)
+#define RUNTIME (60)
+
+#define ALIGN(x, a) (((x) + (a - 1)) & (~((a) - 1)))
+
+FIXTURE(migration)
+{
+ pthread_t *threads;
+ pid_t *pids;
+ int nthreads;
+ int n1;
+ int n2;
+};
+
+FIXTURE_SETUP(migration)
+{
+ int n;
+
+ ASSERT_EQ(numa_available(), 0);
+ self->nthreads = numa_num_task_cpus() - 1;
+ self->n1 = -1;
+ self->n2 = -1;
+
+ for (n = 0; n < numa_max_possible_node(); n++)
+ if (numa_bitmask_isbitset(numa_all_nodes_ptr, n)) {
+ if (self->n1 == -1) {
+ self->n1 = n;
+ } else {
+ self->n2 = n;
+ break;
+ }
+ }
+
+ self->threads = malloc(self->nthreads * sizeof(*self->threads));
+ ASSERT_NE(self->threads, NULL);
+ self->pids = malloc(self->nthreads * sizeof(*self->pids));
+ ASSERT_NE(self->pids, NULL);
+};
+
+FIXTURE_TEARDOWN(migration)
+{
+ free(self->threads);
+ free(self->pids);
+}
+
+int migrate(uint64_t *ptr, int n1, int n2)
+{
+ int ret, tmp;
+ int status = 0;
+ struct timespec ts1, ts2;
+
+ if (clock_gettime(CLOCK_MONOTONIC, &ts1))
+ return -1;
+
+ while (1) {
+ if (clock_gettime(CLOCK_MONOTONIC, &ts2))
+ return -1;
+
+ if (ts2.tv_sec - ts1.tv_sec >= RUNTIME)
+ return 0;
+
+ ret = move_pages(0, 1, (void **) &ptr, &n2, &status,
+ MPOL_MF_MOVE_ALL);
+ if (ret) {
+ if (ret > 0)
+ printf("Didn't migrate %d pages\n", ret);
+ else
+ perror("Couldn't migrate pages");
+ return -2;
+ }
+
+ tmp = n2;
+ n2 = n1;
+ n1 = tmp;
+ }
+
+ return 0;
+}
+
+void *access_mem(void *ptr)
+{
+ uint64_t y = 0;
+ volatile uint64_t *x = ptr;
+
+ while (1) {
+ pthread_testcancel();
+ y += *x;
+ }
+
+ return NULL;
+}
+
+/*
+ * Basic migration entry testing. One thread will move pages back and forth
+ * between nodes whilst other threads try and access them triggering the
+ * migration entry wait paths in the kernel.
+ */
+TEST_F_TIMEOUT(migration, private_anon, 2*RUNTIME)
+{
+ uint64_t *ptr;
+ int i;
+
+ if (self->nthreads < 2 || self->n1 < 0 || self->n2 < 0)
+ SKIP(return, "Not enough threads or NUMA nodes available");
+
+ ptr = mmap(NULL, TWOMEG, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ ASSERT_NE(ptr, MAP_FAILED);
+
+ memset(ptr, 0xde, TWOMEG);
+ for (i = 0; i < self->nthreads - 1; i++)
+ if (pthread_create(&self->threads[i], NULL, access_mem, ptr))
+ perror("Couldn't create thread");
+
+ ASSERT_EQ(migrate(ptr, self->n1, self->n2), 0);
+ for (i = 0; i < self->nthreads - 1; i++)
+ ASSERT_EQ(pthread_cancel(self->threads[i]), 0);
+}
+
+/*
+ * Same as the previous test but with shared memory.
+ */
+TEST_F_TIMEOUT(migration, shared_anon, 2*RUNTIME)
+{
+ pid_t pid;
+ uint64_t *ptr;
+ int i;
+
+ if (self->nthreads < 2 || self->n1 < 0 || self->n2 < 0)
+ SKIP(return, "Not enough threads or NUMA nodes available");
+
+ ptr = mmap(NULL, TWOMEG, PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_ANONYMOUS, -1, 0);
+ ASSERT_NE(ptr, MAP_FAILED);
+
+ memset(ptr, 0xde, TWOMEG);
+ for (i = 0; i < self->nthreads - 1; i++) {
+ pid = fork();
+ if (!pid)
+ access_mem(ptr);
+ else
+ self->pids[i] = pid;
+ }
+
+ ASSERT_EQ(migrate(ptr, self->n1, self->n2), 0);
+ for (i = 0; i < self->nthreads - 1; i++)
+ ASSERT_EQ(kill(self->pids[i], SIGTERM), 0);
+}
+
+/*
+ * Tests the pmd migration entry paths.
+ */
+TEST_F_TIMEOUT(migration, private_anon_thp, 2*RUNTIME)
+{
+ uint64_t *ptr;
+ int i;
+
+ if (self->nthreads < 2 || self->n1 < 0 || self->n2 < 0)
+ SKIP(return, "Not enough threads or NUMA nodes available");
+
+ ptr = mmap(NULL, 2*TWOMEG, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ ASSERT_NE(ptr, MAP_FAILED);
+
+ ptr = (uint64_t *) ALIGN((uintptr_t) ptr, TWOMEG);
+ ASSERT_EQ(madvise(ptr, TWOMEG, MADV_HUGEPAGE), 0);
+ memset(ptr, 0xde, TWOMEG);
+ for (i = 0; i < self->nthreads - 1; i++)
+ if (pthread_create(&self->threads[i], NULL, access_mem, ptr))
+ perror("Couldn't create thread");
+
+ ASSERT_EQ(migrate(ptr, self->n1, self->n2), 0);
+ for (i = 0; i < self->nthreads - 1; i++)
+ ASSERT_EQ(pthread_cancel(self->threads[i]), 0);
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/mm/mlock-random-test.c b/tools/testing/selftests/mm/mlock-random-test.c
new file mode 100644
index 000000000000..782ea94dee2f
--- /dev/null
+++ b/tools/testing/selftests/mm/mlock-random-test.c
@@ -0,0 +1,294 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * It tests the mlock/mlock2() when they are invoked
+ * on randomly memory region.
+ */
+#include <unistd.h>
+#include <sys/resource.h>
+#include <sys/capability.h>
+#include <sys/mman.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#include <time.h>
+#include "mlock2.h"
+
+#define CHUNK_UNIT (128 * 1024)
+#define MLOCK_RLIMIT_SIZE (CHUNK_UNIT * 2)
+#define MLOCK_WITHIN_LIMIT_SIZE CHUNK_UNIT
+#define MLOCK_OUTOF_LIMIT_SIZE (CHUNK_UNIT * 3)
+
+#define TEST_LOOP 100
+#define PAGE_ALIGN(size, ps) (((size) + ((ps) - 1)) & ~((ps) - 1))
+
+int set_cap_limits(rlim_t max)
+{
+ struct rlimit new;
+ cap_t cap = cap_init();
+
+ new.rlim_cur = max;
+ new.rlim_max = max;
+ if (setrlimit(RLIMIT_MEMLOCK, &new)) {
+ perror("setrlimit() returns error\n");
+ return -1;
+ }
+
+ /* drop capabilities including CAP_IPC_LOCK */
+ if (cap_set_proc(cap)) {
+ perror("cap_set_proc() returns error\n");
+ return -2;
+ }
+
+ return 0;
+}
+
+int get_proc_locked_vm_size(void)
+{
+ FILE *f;
+ int ret = -1;
+ char line[1024] = {0};
+ unsigned long lock_size = 0;
+
+ f = fopen("/proc/self/status", "r");
+ if (!f) {
+ perror("fopen");
+ return -1;
+ }
+
+ while (fgets(line, 1024, f)) {
+ if (strstr(line, "VmLck")) {
+ ret = sscanf(line, "VmLck:\t%8lu kB", &lock_size);
+ if (ret <= 0) {
+ printf("sscanf() on VmLck error: %s: %d\n",
+ line, ret);
+ fclose(f);
+ return -1;
+ }
+ fclose(f);
+ return (int)(lock_size << 10);
+ }
+ }
+
+ perror("cannot parse VmLck in /proc/self/status\n");
+ fclose(f);
+ return -1;
+}
+
+/*
+ * Get the MMUPageSize of the memory region including input
+ * address from proc file.
+ *
+ * return value: on error case, 0 will be returned.
+ * Otherwise the page size(in bytes) is returned.
+ */
+int get_proc_page_size(unsigned long addr)
+{
+ FILE *smaps;
+ char *line;
+ unsigned long mmupage_size = 0;
+ size_t size;
+
+ smaps = seek_to_smaps_entry(addr);
+ if (!smaps) {
+ printf("Unable to parse /proc/self/smaps\n");
+ return 0;
+ }
+
+ while (getline(&line, &size, smaps) > 0) {
+ if (!strstr(line, "MMUPageSize")) {
+ free(line);
+ line = NULL;
+ size = 0;
+ continue;
+ }
+
+ /* found the MMUPageSize of this section */
+ if (sscanf(line, "MMUPageSize: %8lu kB",
+ &mmupage_size) < 1) {
+ printf("Unable to parse smaps entry for Size:%s\n",
+ line);
+ break;
+ }
+
+ }
+ free(line);
+ if (smaps)
+ fclose(smaps);
+ return mmupage_size << 10;
+}
+
+/*
+ * Test mlock/mlock2() on provided memory chunk.
+ * It expects the mlock/mlock2() to be successful (within rlimit)
+ *
+ * With allocated memory chunk [p, p + alloc_size), this
+ * test will choose start/len randomly to perform mlock/mlock2
+ * [start, start + len] memory range. The range is within range
+ * of the allocated chunk.
+ *
+ * The memory region size alloc_size is within the rlimit.
+ * So we always expect a success of mlock/mlock2.
+ *
+ * VmLck is assumed to be 0 before this test.
+ *
+ * return value: 0 - success
+ * else: failure
+ */
+int test_mlock_within_limit(char *p, int alloc_size)
+{
+ int i;
+ int ret = 0;
+ int locked_vm_size = 0;
+ struct rlimit cur;
+ int page_size = 0;
+
+ getrlimit(RLIMIT_MEMLOCK, &cur);
+ if (cur.rlim_cur < alloc_size) {
+ printf("alloc_size[%d] < %u rlimit,lead to mlock failure\n",
+ alloc_size, (unsigned int)cur.rlim_cur);
+ return -1;
+ }
+
+ srand(time(NULL));
+ for (i = 0; i < TEST_LOOP; i++) {
+ /*
+ * - choose mlock/mlock2 randomly
+ * - choose lock_size randomly but lock_size < alloc_size
+ * - choose start_offset randomly but p+start_offset+lock_size
+ * < p+alloc_size
+ */
+ int is_mlock = !!(rand() % 2);
+ int lock_size = rand() % alloc_size;
+ int start_offset = rand() % (alloc_size - lock_size);
+
+ if (is_mlock)
+ ret = mlock(p + start_offset, lock_size);
+ else
+ ret = mlock2_(p + start_offset, lock_size,
+ MLOCK_ONFAULT);
+
+ if (ret) {
+ printf("%s() failure at |%p(%d)| mlock:|%p(%d)|\n",
+ is_mlock ? "mlock" : "mlock2",
+ p, alloc_size,
+ p + start_offset, lock_size);
+ return ret;
+ }
+ }
+
+ /*
+ * Check VmLck left by the tests.
+ */
+ locked_vm_size = get_proc_locked_vm_size();
+ page_size = get_proc_page_size((unsigned long)p);
+ if (page_size == 0) {
+ printf("cannot get proc MMUPageSize\n");
+ return -1;
+ }
+
+ if (locked_vm_size > PAGE_ALIGN(alloc_size, page_size) + page_size) {
+ printf("test_mlock_within_limit() left VmLck:%d on %d chunk\n",
+ locked_vm_size, alloc_size);
+ return -1;
+ }
+
+ return 0;
+}
+
+
+/*
+ * We expect the mlock/mlock2() to be fail (outof limitation)
+ *
+ * With allocated memory chunk [p, p + alloc_size), this
+ * test will randomly choose start/len and perform mlock/mlock2
+ * on [start, start+len] range.
+ *
+ * The memory region size alloc_size is above the rlimit.
+ * And the len to be locked is higher than rlimit.
+ * So we always expect a failure of mlock/mlock2.
+ * No locked page number should be increased as a side effect.
+ *
+ * return value: 0 - success
+ * else: failure
+ */
+int test_mlock_outof_limit(char *p, int alloc_size)
+{
+ int i;
+ int ret = 0;
+ int locked_vm_size = 0, old_locked_vm_size = 0;
+ struct rlimit cur;
+
+ getrlimit(RLIMIT_MEMLOCK, &cur);
+ if (cur.rlim_cur >= alloc_size) {
+ printf("alloc_size[%d] >%u rlimit, violates test condition\n",
+ alloc_size, (unsigned int)cur.rlim_cur);
+ return -1;
+ }
+
+ old_locked_vm_size = get_proc_locked_vm_size();
+ srand(time(NULL));
+ for (i = 0; i < TEST_LOOP; i++) {
+ int is_mlock = !!(rand() % 2);
+ int lock_size = (rand() % (alloc_size - cur.rlim_cur))
+ + cur.rlim_cur;
+ int start_offset = rand() % (alloc_size - lock_size);
+
+ if (is_mlock)
+ ret = mlock(p + start_offset, lock_size);
+ else
+ ret = mlock2_(p + start_offset, lock_size,
+ MLOCK_ONFAULT);
+ if (ret == 0) {
+ printf("%s() succeeds? on %p(%d) mlock%p(%d)\n",
+ is_mlock ? "mlock" : "mlock2",
+ p, alloc_size,
+ p + start_offset, lock_size);
+ return -1;
+ }
+ }
+
+ locked_vm_size = get_proc_locked_vm_size();
+ if (locked_vm_size != old_locked_vm_size) {
+ printf("tests leads to new mlocked page: old[%d], new[%d]\n",
+ old_locked_vm_size,
+ locked_vm_size);
+ return -1;
+ }
+
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ char *p = NULL;
+ int ret = 0;
+
+ if (set_cap_limits(MLOCK_RLIMIT_SIZE))
+ return -1;
+
+ p = malloc(MLOCK_WITHIN_LIMIT_SIZE);
+ if (p == NULL) {
+ perror("malloc() failure\n");
+ return -1;
+ }
+ ret = test_mlock_within_limit(p, MLOCK_WITHIN_LIMIT_SIZE);
+ if (ret)
+ return ret;
+ munlock(p, MLOCK_WITHIN_LIMIT_SIZE);
+ free(p);
+
+
+ p = malloc(MLOCK_OUTOF_LIMIT_SIZE);
+ if (p == NULL) {
+ perror("malloc() failure\n");
+ return -1;
+ }
+ ret = test_mlock_outof_limit(p, MLOCK_OUTOF_LIMIT_SIZE);
+ if (ret)
+ return ret;
+ munlock(p, MLOCK_OUTOF_LIMIT_SIZE);
+ free(p);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/mlock2-tests.c b/tools/testing/selftests/mm/mlock2-tests.c
new file mode 100644
index 000000000000..11b2301f3aa3
--- /dev/null
+++ b/tools/testing/selftests/mm/mlock2-tests.c
@@ -0,0 +1,520 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sys/mman.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+#include <stdbool.h>
+#include "mlock2.h"
+
+#include "../kselftest.h"
+
+struct vm_boundaries {
+ unsigned long start;
+ unsigned long end;
+};
+
+static int get_vm_area(unsigned long addr, struct vm_boundaries *area)
+{
+ FILE *file;
+ int ret = 1;
+ char line[1024] = {0};
+ char *end_addr;
+ char *stop;
+ unsigned long start;
+ unsigned long end;
+
+ if (!area)
+ return ret;
+
+ file = fopen("/proc/self/maps", "r");
+ if (!file) {
+ perror("fopen");
+ return ret;
+ }
+
+ memset(area, 0, sizeof(struct vm_boundaries));
+
+ while(fgets(line, 1024, file)) {
+ end_addr = strchr(line, '-');
+ if (!end_addr) {
+ printf("cannot parse /proc/self/maps\n");
+ goto out;
+ }
+ *end_addr = '\0';
+ end_addr++;
+ stop = strchr(end_addr, ' ');
+ if (!stop) {
+ printf("cannot parse /proc/self/maps\n");
+ goto out;
+ }
+ stop = '\0';
+
+ sscanf(line, "%lx", &start);
+ sscanf(end_addr, "%lx", &end);
+
+ if (start <= addr && end > addr) {
+ area->start = start;
+ area->end = end;
+ ret = 0;
+ goto out;
+ }
+ }
+out:
+ fclose(file);
+ return ret;
+}
+
+#define VMFLAGS "VmFlags:"
+
+static bool is_vmflag_set(unsigned long addr, const char *vmflag)
+{
+ char *line = NULL;
+ char *flags;
+ size_t size = 0;
+ bool ret = false;
+ FILE *smaps;
+
+ smaps = seek_to_smaps_entry(addr);
+ if (!smaps) {
+ printf("Unable to parse /proc/self/smaps\n");
+ goto out;
+ }
+
+ while (getline(&line, &size, smaps) > 0) {
+ if (!strstr(line, VMFLAGS)) {
+ free(line);
+ line = NULL;
+ size = 0;
+ continue;
+ }
+
+ flags = line + strlen(VMFLAGS);
+ ret = (strstr(flags, vmflag) != NULL);
+ goto out;
+ }
+
+out:
+ free(line);
+ fclose(smaps);
+ return ret;
+}
+
+#define SIZE "Size:"
+#define RSS "Rss:"
+#define LOCKED "lo"
+
+static unsigned long get_value_for_name(unsigned long addr, const char *name)
+{
+ char *line = NULL;
+ size_t size = 0;
+ char *value_ptr;
+ FILE *smaps = NULL;
+ unsigned long value = -1UL;
+
+ smaps = seek_to_smaps_entry(addr);
+ if (!smaps) {
+ printf("Unable to parse /proc/self/smaps\n");
+ goto out;
+ }
+
+ while (getline(&line, &size, smaps) > 0) {
+ if (!strstr(line, name)) {
+ free(line);
+ line = NULL;
+ size = 0;
+ continue;
+ }
+
+ value_ptr = line + strlen(name);
+ if (sscanf(value_ptr, "%lu kB", &value) < 1) {
+ printf("Unable to parse smaps entry for Size\n");
+ goto out;
+ }
+ break;
+ }
+
+out:
+ if (smaps)
+ fclose(smaps);
+ free(line);
+ return value;
+}
+
+static bool is_vma_lock_on_fault(unsigned long addr)
+{
+ bool locked;
+ unsigned long vma_size, vma_rss;
+
+ locked = is_vmflag_set(addr, LOCKED);
+ if (!locked)
+ return false;
+
+ vma_size = get_value_for_name(addr, SIZE);
+ vma_rss = get_value_for_name(addr, RSS);
+
+ /* only one page is faulted in */
+ return (vma_rss < vma_size);
+}
+
+#define PRESENT_BIT 0x8000000000000000ULL
+#define PFN_MASK 0x007FFFFFFFFFFFFFULL
+#define UNEVICTABLE_BIT (1UL << 18)
+
+static int lock_check(unsigned long addr)
+{
+ bool locked;
+ unsigned long vma_size, vma_rss;
+
+ locked = is_vmflag_set(addr, LOCKED);
+ if (!locked)
+ return false;
+
+ vma_size = get_value_for_name(addr, SIZE);
+ vma_rss = get_value_for_name(addr, RSS);
+
+ return (vma_rss == vma_size);
+}
+
+static int unlock_lock_check(char *map)
+{
+ if (is_vmflag_set((unsigned long)map, LOCKED)) {
+ printf("VMA flag %s is present on page 1 after unlock\n", LOCKED);
+ return 1;
+ }
+
+ return 0;
+}
+
+static int test_mlock_lock()
+{
+ char *map;
+ int ret = 1;
+ unsigned long page_size = getpagesize();
+
+ map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ if (map == MAP_FAILED) {
+ perror("test_mlock_locked mmap");
+ goto out;
+ }
+
+ if (mlock2_(map, 2 * page_size, 0)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("mlock2(0)");
+ goto unmap;
+ }
+
+ if (!lock_check((unsigned long)map))
+ goto unmap;
+
+ /* Now unlock and recheck attributes */
+ if (munlock(map, 2 * page_size)) {
+ perror("munlock()");
+ goto unmap;
+ }
+
+ ret = unlock_lock_check(map);
+
+unmap:
+ munmap(map, 2 * page_size);
+out:
+ return ret;
+}
+
+static int onfault_check(char *map)
+{
+ *map = 'a';
+ if (!is_vma_lock_on_fault((unsigned long)map)) {
+ printf("VMA is not marked for lock on fault\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+static int unlock_onfault_check(char *map)
+{
+ unsigned long page_size = getpagesize();
+
+ if (is_vma_lock_on_fault((unsigned long)map) ||
+ is_vma_lock_on_fault((unsigned long)map + page_size)) {
+ printf("VMA is still lock on fault after unlock\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+static int test_mlock_onfault()
+{
+ char *map;
+ int ret = 1;
+ unsigned long page_size = getpagesize();
+
+ map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ if (map == MAP_FAILED) {
+ perror("test_mlock_locked mmap");
+ goto out;
+ }
+
+ if (mlock2_(map, 2 * page_size, MLOCK_ONFAULT)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("mlock2(MLOCK_ONFAULT)");
+ goto unmap;
+ }
+
+ if (onfault_check(map))
+ goto unmap;
+
+ /* Now unlock and recheck attributes */
+ if (munlock(map, 2 * page_size)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("munlock()");
+ goto unmap;
+ }
+
+ ret = unlock_onfault_check(map);
+unmap:
+ munmap(map, 2 * page_size);
+out:
+ return ret;
+}
+
+static int test_lock_onfault_of_present()
+{
+ char *map;
+ int ret = 1;
+ unsigned long page_size = getpagesize();
+
+ map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ if (map == MAP_FAILED) {
+ perror("test_mlock_locked mmap");
+ goto out;
+ }
+
+ *map = 'a';
+
+ if (mlock2_(map, 2 * page_size, MLOCK_ONFAULT)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("mlock2(MLOCK_ONFAULT)");
+ goto unmap;
+ }
+
+ if (!is_vma_lock_on_fault((unsigned long)map) ||
+ !is_vma_lock_on_fault((unsigned long)map + page_size)) {
+ printf("VMA with present pages is not marked lock on fault\n");
+ goto unmap;
+ }
+ ret = 0;
+unmap:
+ munmap(map, 2 * page_size);
+out:
+ return ret;
+}
+
+static int test_munlockall()
+{
+ char *map;
+ int ret = 1;
+ unsigned long page_size = getpagesize();
+
+ map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+
+ if (map == MAP_FAILED) {
+ perror("test_munlockall mmap");
+ goto out;
+ }
+
+ if (mlockall(MCL_CURRENT)) {
+ perror("mlockall(MCL_CURRENT)");
+ goto out;
+ }
+
+ if (!lock_check((unsigned long)map))
+ goto unmap;
+
+ if (munlockall()) {
+ perror("munlockall()");
+ goto unmap;
+ }
+
+ if (unlock_lock_check(map))
+ goto unmap;
+
+ munmap(map, 2 * page_size);
+
+ map = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+
+ if (map == MAP_FAILED) {
+ perror("test_munlockall second mmap");
+ goto out;
+ }
+
+ if (mlockall(MCL_CURRENT | MCL_ONFAULT)) {
+ perror("mlockall(MCL_CURRENT | MCL_ONFAULT)");
+ goto unmap;
+ }
+
+ if (onfault_check(map))
+ goto unmap;
+
+ if (munlockall()) {
+ perror("munlockall()");
+ goto unmap;
+ }
+
+ if (unlock_onfault_check(map))
+ goto unmap;
+
+ if (mlockall(MCL_CURRENT | MCL_FUTURE)) {
+ perror("mlockall(MCL_CURRENT | MCL_FUTURE)");
+ goto out;
+ }
+
+ if (!lock_check((unsigned long)map))
+ goto unmap;
+
+ if (munlockall()) {
+ perror("munlockall()");
+ goto unmap;
+ }
+
+ ret = unlock_lock_check(map);
+
+unmap:
+ munmap(map, 2 * page_size);
+out:
+ munlockall();
+ return ret;
+}
+
+static int test_vma_management(bool call_mlock)
+{
+ int ret = 1;
+ void *map;
+ unsigned long page_size = getpagesize();
+ struct vm_boundaries page1;
+ struct vm_boundaries page2;
+ struct vm_boundaries page3;
+
+ map = mmap(NULL, 3 * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+ if (map == MAP_FAILED) {
+ perror("mmap()");
+ return ret;
+ }
+
+ if (call_mlock && mlock2_(map, 3 * page_size, MLOCK_ONFAULT)) {
+ if (errno == ENOSYS) {
+ printf("Cannot call new mlock family, skipping test\n");
+ _exit(KSFT_SKIP);
+ }
+ perror("mlock(ONFAULT)\n");
+ goto out;
+ }
+
+ if (get_vm_area((unsigned long)map, &page1) ||
+ get_vm_area((unsigned long)map + page_size, &page2) ||
+ get_vm_area((unsigned long)map + page_size * 2, &page3)) {
+ printf("couldn't find mapping in /proc/self/maps\n");
+ goto out;
+ }
+
+ /*
+ * Before we unlock a portion, we need to that all three pages are in
+ * the same VMA. If they are not we abort this test (Note that this is
+ * not a failure)
+ */
+ if (page1.start != page2.start || page2.start != page3.start) {
+ printf("VMAs are not merged to start, aborting test\n");
+ ret = 0;
+ goto out;
+ }
+
+ if (munlock(map + page_size, page_size)) {
+ perror("munlock()");
+ goto out;
+ }
+
+ if (get_vm_area((unsigned long)map, &page1) ||
+ get_vm_area((unsigned long)map + page_size, &page2) ||
+ get_vm_area((unsigned long)map + page_size * 2, &page3)) {
+ printf("couldn't find mapping in /proc/self/maps\n");
+ goto out;
+ }
+
+ /* All three VMAs should be different */
+ if (page1.start == page2.start || page2.start == page3.start) {
+ printf("failed to split VMA for munlock\n");
+ goto out;
+ }
+
+ /* Now unlock the first and third page and check the VMAs again */
+ if (munlock(map, page_size * 3)) {
+ perror("munlock()");
+ goto out;
+ }
+
+ if (get_vm_area((unsigned long)map, &page1) ||
+ get_vm_area((unsigned long)map + page_size, &page2) ||
+ get_vm_area((unsigned long)map + page_size * 2, &page3)) {
+ printf("couldn't find mapping in /proc/self/maps\n");
+ goto out;
+ }
+
+ /* Now all three VMAs should be the same */
+ if (page1.start != page2.start || page2.start != page3.start) {
+ printf("failed to merge VMAs after munlock\n");
+ goto out;
+ }
+
+ ret = 0;
+out:
+ munmap(map, 3 * page_size);
+ return ret;
+}
+
+static int test_mlockall(int (test_function)(bool call_mlock))
+{
+ int ret = 1;
+
+ if (mlockall(MCL_CURRENT | MCL_ONFAULT | MCL_FUTURE)) {
+ perror("mlockall");
+ return ret;
+ }
+
+ ret = test_function(false);
+ munlockall();
+ return ret;
+}
+
+int main(int argc, char **argv)
+{
+ int ret = 0;
+ ret += test_mlock_lock();
+ ret += test_mlock_onfault();
+ ret += test_munlockall();
+ ret += test_lock_onfault_of_present();
+ ret += test_vma_management(true);
+ ret += test_mlockall(test_vma_management);
+ return ret;
+}
diff --git a/tools/testing/selftests/mm/mlock2.h b/tools/testing/selftests/mm/mlock2.h
new file mode 100644
index 000000000000..2a6e76c226bc
--- /dev/null
+++ b/tools/testing/selftests/mm/mlock2.h
@@ -0,0 +1,63 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <syscall.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#ifndef MLOCK_ONFAULT
+#define MLOCK_ONFAULT 1
+#endif
+
+#ifndef MCL_ONFAULT
+#define MCL_ONFAULT (MCL_FUTURE << 1)
+#endif
+
+static int mlock2_(void *start, size_t len, int flags)
+{
+#ifdef __NR_mlock2
+ return syscall(__NR_mlock2, start, len, flags);
+#else
+ errno = ENOSYS;
+ return -1;
+#endif
+}
+
+static FILE *seek_to_smaps_entry(unsigned long addr)
+{
+ FILE *file;
+ char *line = NULL;
+ size_t size = 0;
+ unsigned long start, end;
+ char perms[5];
+ unsigned long offset;
+ char dev[32];
+ unsigned long inode;
+ char path[BUFSIZ];
+
+ file = fopen("/proc/self/smaps", "r");
+ if (!file) {
+ perror("fopen smaps");
+ _exit(1);
+ }
+
+ while (getline(&line, &size, file) > 0) {
+ if (sscanf(line, "%lx-%lx %s %lx %s %lu %s\n",
+ &start, &end, perms, &offset, dev, &inode, path) < 6)
+ goto next;
+
+ if (start <= addr && addr < end)
+ goto out;
+
+next:
+ free(line);
+ line = NULL;
+ size = 0;
+ }
+
+ fclose(file);
+ file = NULL;
+
+out:
+ free(line);
+ return file;
+}
diff --git a/tools/testing/selftests/mm/mrelease_test.c b/tools/testing/selftests/mm/mrelease_test.c
new file mode 100644
index 000000000000..6c62966ab5db
--- /dev/null
+++ b/tools/testing/selftests/mm/mrelease_test.c
@@ -0,0 +1,206 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2022 Google LLC
+ */
+#define _GNU_SOURCE
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "util.h"
+
+#include "../kselftest.h"
+
+#ifndef __NR_pidfd_open
+#define __NR_pidfd_open -1
+#endif
+
+#ifndef __NR_process_mrelease
+#define __NR_process_mrelease -1
+#endif
+
+#define MB(x) (x << 20)
+#define MAX_SIZE_MB 1024
+
+static int alloc_noexit(unsigned long nr_pages, int pipefd)
+{
+ int ppid = getppid();
+ int timeout = 10; /* 10sec timeout to get killed */
+ unsigned long i;
+ char *buf;
+
+ buf = (char *)mmap(NULL, nr_pages * PAGE_SIZE, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANON, 0, 0);
+ if (buf == MAP_FAILED) {
+ perror("mmap failed, halting the test");
+ return KSFT_FAIL;
+ }
+
+ for (i = 0; i < nr_pages; i++)
+ *((unsigned long *)(buf + (i * PAGE_SIZE))) = i;
+
+ /* Signal the parent that the child is ready */
+ if (write(pipefd, "", 1) < 0) {
+ perror("write");
+ return KSFT_FAIL;
+ }
+
+ /* Wait to be killed (when reparenting happens) */
+ while (getppid() == ppid && timeout > 0) {
+ sleep(1);
+ timeout--;
+ }
+
+ munmap(buf, nr_pages * PAGE_SIZE);
+
+ return (timeout > 0) ? KSFT_PASS : KSFT_FAIL;
+}
+
+/* The process_mrelease calls in this test are expected to fail */
+static void run_negative_tests(int pidfd)
+{
+ int res;
+ /* Test invalid flags. Expect to fail with EINVAL error code. */
+ if (!syscall(__NR_process_mrelease, pidfd, (unsigned int)-1) ||
+ errno != EINVAL) {
+ res = (errno == ENOSYS ? KSFT_SKIP : KSFT_FAIL);
+ perror("process_mrelease with wrong flags");
+ exit(res);
+ }
+ /*
+ * Test reaping while process is alive with no pending SIGKILL.
+ * Expect to fail with EINVAL error code.
+ */
+ if (!syscall(__NR_process_mrelease, pidfd, 0) || errno != EINVAL) {
+ res = (errno == ENOSYS ? KSFT_SKIP : KSFT_FAIL);
+ perror("process_mrelease on a live process");
+ exit(res);
+ }
+}
+
+static int child_main(int pipefd[], size_t size)
+{
+ int res;
+
+ /* Allocate and fault-in memory and wait to be killed */
+ close(pipefd[0]);
+ res = alloc_noexit(MB(size) / PAGE_SIZE, pipefd[1]);
+ close(pipefd[1]);
+ return res;
+}
+
+int main(void)
+{
+ int pipefd[2], pidfd;
+ bool success, retry;
+ size_t size;
+ pid_t pid;
+ char byte;
+ int res;
+
+ /* Test a wrong pidfd */
+ if (!syscall(__NR_process_mrelease, -1, 0) || errno != EBADF) {
+ res = (errno == ENOSYS ? KSFT_SKIP : KSFT_FAIL);
+ perror("process_mrelease with wrong pidfd");
+ exit(res);
+ }
+
+ /* Start the test with 1MB child memory allocation */
+ size = 1;
+retry:
+ /*
+ * Pipe for the child to signal when it's done allocating
+ * memory
+ */
+ if (pipe(pipefd)) {
+ perror("pipe");
+ exit(KSFT_FAIL);
+ }
+ pid = fork();
+ if (pid < 0) {
+ perror("fork");
+ close(pipefd[0]);
+ close(pipefd[1]);
+ exit(KSFT_FAIL);
+ }
+
+ if (pid == 0) {
+ /* Child main routine */
+ res = child_main(pipefd, size);
+ exit(res);
+ }
+
+ /*
+ * Parent main routine:
+ * Wait for the child to finish allocations, then kill and reap
+ */
+ close(pipefd[1]);
+ /* Block until the child is ready */
+ res = read(pipefd[0], &byte, 1);
+ close(pipefd[0]);
+ if (res < 0) {
+ perror("read");
+ if (!kill(pid, SIGKILL))
+ waitpid(pid, NULL, 0);
+ exit(KSFT_FAIL);
+ }
+
+ pidfd = syscall(__NR_pidfd_open, pid, 0);
+ if (pidfd < 0) {
+ perror("pidfd_open");
+ if (!kill(pid, SIGKILL))
+ waitpid(pid, NULL, 0);
+ exit(KSFT_FAIL);
+ }
+
+ /* Run negative tests which require a live child */
+ run_negative_tests(pidfd);
+
+ if (kill(pid, SIGKILL)) {
+ res = (errno == ENOSYS ? KSFT_SKIP : KSFT_FAIL);
+ perror("kill");
+ exit(res);
+ }
+
+ success = (syscall(__NR_process_mrelease, pidfd, 0) == 0);
+ if (!success) {
+ /*
+ * If we failed to reap because the child exited too soon,
+ * before we could call process_mrelease. Double child's memory
+ * which causes it to spend more time on cleanup and increases
+ * our chances of reaping its memory before it exits.
+ * Retry until we succeed or reach MAX_SIZE_MB.
+ */
+ if (errno == ESRCH) {
+ retry = (size <= MAX_SIZE_MB);
+ } else {
+ res = (errno == ENOSYS ? KSFT_SKIP : KSFT_FAIL);
+ perror("process_mrelease");
+ waitpid(pid, NULL, 0);
+ exit(res);
+ }
+ }
+
+ /* Cleanup to prevent zombies */
+ if (waitpid(pid, NULL, 0) < 0) {
+ perror("waitpid");
+ exit(KSFT_FAIL);
+ }
+ close(pidfd);
+
+ if (!success) {
+ if (retry) {
+ size *= 2;
+ goto retry;
+ }
+ printf("All process_mrelease attempts failed!\n");
+ exit(KSFT_FAIL);
+ }
+
+ printf("Success reaping a child with %zuMB of memory allocations\n",
+ size);
+ return KSFT_PASS;
+}
diff --git a/tools/testing/selftests/mm/mremap_dontunmap.c b/tools/testing/selftests/mm/mremap_dontunmap.c
new file mode 100644
index 000000000000..f01dc4a85b0b
--- /dev/null
+++ b/tools/testing/selftests/mm/mremap_dontunmap.c
@@ -0,0 +1,364 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Tests for mremap w/ MREMAP_DONTUNMAP.
+ *
+ * Copyright 2020, Brian Geffon <bgeffon@google.com>
+ */
+#define _GNU_SOURCE
+#include <sys/mman.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "../kselftest.h"
+
+#ifndef MREMAP_DONTUNMAP
+#define MREMAP_DONTUNMAP 4
+#endif
+
+unsigned long page_size;
+char *page_buffer;
+
+static void dump_maps(void)
+{
+ char cmd[32];
+
+ snprintf(cmd, sizeof(cmd), "cat /proc/%d/maps", getpid());
+ system(cmd);
+}
+
+#define BUG_ON(condition, description) \
+ do { \
+ if (condition) { \
+ fprintf(stderr, "[FAIL]\t%s():%d\t%s:%s\n", __func__, \
+ __LINE__, (description), strerror(errno)); \
+ dump_maps(); \
+ exit(1); \
+ } \
+ } while (0)
+
+// Try a simple operation for to "test" for kernel support this prevents
+// reporting tests as failed when it's run on an older kernel.
+static int kernel_support_for_mremap_dontunmap()
+{
+ int ret = 0;
+ unsigned long num_pages = 1;
+ void *source_mapping = mmap(NULL, num_pages * page_size, PROT_NONE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+
+ // This simple remap should only fail if MREMAP_DONTUNMAP isn't
+ // supported.
+ void *dest_mapping =
+ mremap(source_mapping, num_pages * page_size, num_pages * page_size,
+ MREMAP_DONTUNMAP | MREMAP_MAYMOVE, 0);
+ if (dest_mapping == MAP_FAILED) {
+ ret = errno;
+ } else {
+ BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
+ "unable to unmap destination mapping");
+ }
+
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
+ return ret;
+}
+
+// This helper will just validate that an entire mapping contains the expected
+// byte.
+static int check_region_contains_byte(void *addr, unsigned long size, char byte)
+{
+ BUG_ON(size & (page_size - 1),
+ "check_region_contains_byte expects page multiples");
+ BUG_ON((unsigned long)addr & (page_size - 1),
+ "check_region_contains_byte expects page alignment");
+
+ memset(page_buffer, byte, page_size);
+
+ unsigned long num_pages = size / page_size;
+ unsigned long i;
+
+ // Compare each page checking that it contains our expected byte.
+ for (i = 0; i < num_pages; ++i) {
+ int ret =
+ memcmp(addr + (i * page_size), page_buffer, page_size);
+ if (ret) {
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+// this test validates that MREMAP_DONTUNMAP moves the pagetables while leaving
+// the source mapping mapped.
+static void mremap_dontunmap_simple()
+{
+ unsigned long num_pages = 5;
+
+ void *source_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+
+ memset(source_mapping, 'a', num_pages * page_size);
+
+ // Try to just move the whole mapping anywhere (not fixed).
+ void *dest_mapping =
+ mremap(source_mapping, num_pages * page_size, num_pages * page_size,
+ MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL);
+ BUG_ON(dest_mapping == MAP_FAILED, "mremap");
+
+ // Validate that the pages have been moved, we know they were moved if
+ // the dest_mapping contains a's.
+ BUG_ON(check_region_contains_byte
+ (dest_mapping, num_pages * page_size, 'a') != 0,
+ "pages did not migrate");
+ BUG_ON(check_region_contains_byte
+ (source_mapping, num_pages * page_size, 0) != 0,
+ "source should have no ptes");
+
+ BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
+}
+
+// This test validates that MREMAP_DONTUNMAP on a shared mapping works as expected.
+static void mremap_dontunmap_simple_shmem()
+{
+ unsigned long num_pages = 5;
+
+ int mem_fd = memfd_create("memfd", MFD_CLOEXEC);
+ BUG_ON(mem_fd < 0, "memfd_create");
+
+ BUG_ON(ftruncate(mem_fd, num_pages * page_size) < 0,
+ "ftruncate");
+
+ void *source_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_FILE | MAP_SHARED, mem_fd, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+
+ BUG_ON(close(mem_fd) < 0, "close");
+
+ memset(source_mapping, 'a', num_pages * page_size);
+
+ // Try to just move the whole mapping anywhere (not fixed).
+ void *dest_mapping =
+ mremap(source_mapping, num_pages * page_size, num_pages * page_size,
+ MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL);
+ if (dest_mapping == MAP_FAILED && errno == EINVAL) {
+ // Old kernel which doesn't support MREMAP_DONTUNMAP on shmem.
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
+ return;
+ }
+
+ BUG_ON(dest_mapping == MAP_FAILED, "mremap");
+
+ // Validate that the pages have been moved, we know they were moved if
+ // the dest_mapping contains a's.
+ BUG_ON(check_region_contains_byte
+ (dest_mapping, num_pages * page_size, 'a') != 0,
+ "pages did not migrate");
+
+ // Because the region is backed by shmem, we will actually see the same
+ // memory at the source location still.
+ BUG_ON(check_region_contains_byte
+ (source_mapping, num_pages * page_size, 'a') != 0,
+ "source should have no ptes");
+
+ BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
+}
+
+// This test validates MREMAP_DONTUNMAP will move page tables to a specific
+// destination using MREMAP_FIXED, also while validating that the source
+// remains intact.
+static void mremap_dontunmap_simple_fixed()
+{
+ unsigned long num_pages = 5;
+
+ // Since we want to guarantee that we can remap to a point, we will
+ // create a mapping up front.
+ void *dest_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(dest_mapping == MAP_FAILED, "mmap");
+ memset(dest_mapping, 'X', num_pages * page_size);
+
+ void *source_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+ memset(source_mapping, 'a', num_pages * page_size);
+
+ void *remapped_mapping =
+ mremap(source_mapping, num_pages * page_size, num_pages * page_size,
+ MREMAP_FIXED | MREMAP_DONTUNMAP | MREMAP_MAYMOVE,
+ dest_mapping);
+ BUG_ON(remapped_mapping == MAP_FAILED, "mremap");
+ BUG_ON(remapped_mapping != dest_mapping,
+ "mremap should have placed the remapped mapping at dest_mapping");
+
+ // The dest mapping will have been unmap by mremap so we expect the Xs
+ // to be gone and replaced with a's.
+ BUG_ON(check_region_contains_byte
+ (dest_mapping, num_pages * page_size, 'a') != 0,
+ "pages did not migrate");
+
+ // And the source mapping will have had its ptes dropped.
+ BUG_ON(check_region_contains_byte
+ (source_mapping, num_pages * page_size, 0) != 0,
+ "source should have no ptes");
+
+ BUG_ON(munmap(dest_mapping, num_pages * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
+}
+
+// This test validates that we can MREMAP_DONTUNMAP for a portion of an
+// existing mapping.
+static void mremap_dontunmap_partial_mapping()
+{
+ /*
+ * source mapping:
+ * --------------
+ * | aaaaaaaaaa |
+ * --------------
+ * to become:
+ * --------------
+ * | aaaaa00000 |
+ * --------------
+ * With the destination mapping containing 5 pages of As.
+ * ---------
+ * | aaaaa |
+ * ---------
+ */
+ unsigned long num_pages = 10;
+ void *source_mapping =
+ mmap(NULL, num_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+ memset(source_mapping, 'a', num_pages * page_size);
+
+ // We will grab the last 5 pages of the source and move them.
+ void *dest_mapping =
+ mremap(source_mapping + (5 * page_size), 5 * page_size,
+ 5 * page_size,
+ MREMAP_DONTUNMAP | MREMAP_MAYMOVE, NULL);
+ BUG_ON(dest_mapping == MAP_FAILED, "mremap");
+
+ // We expect the first 5 pages of the source to contain a's and the
+ // final 5 pages to contain zeros.
+ BUG_ON(check_region_contains_byte(source_mapping, 5 * page_size, 'a') !=
+ 0, "first 5 pages of source should have original pages");
+ BUG_ON(check_region_contains_byte
+ (source_mapping + (5 * page_size), 5 * page_size, 0) != 0,
+ "final 5 pages of source should have no ptes");
+
+ // Finally we expect the destination to have 5 pages worth of a's.
+ BUG_ON(check_region_contains_byte(dest_mapping, 5 * page_size, 'a') !=
+ 0, "dest mapping should contain ptes from the source");
+
+ BUG_ON(munmap(dest_mapping, 5 * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, num_pages * page_size) == -1,
+ "unable to unmap source mapping");
+}
+
+// This test validates that we can remap over only a portion of a mapping.
+static void mremap_dontunmap_partial_mapping_overwrite(void)
+{
+ /*
+ * source mapping:
+ * ---------
+ * |aaaaa|
+ * ---------
+ * dest mapping initially:
+ * -----------
+ * |XXXXXXXXXX|
+ * ------------
+ * Source to become:
+ * ---------
+ * |00000|
+ * ---------
+ * With the destination mapping containing 5 pages of As.
+ * ------------
+ * |aaaaaXXXXX|
+ * ------------
+ */
+ void *source_mapping =
+ mmap(NULL, 5 * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(source_mapping == MAP_FAILED, "mmap");
+ memset(source_mapping, 'a', 5 * page_size);
+
+ void *dest_mapping =
+ mmap(NULL, 10 * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(dest_mapping == MAP_FAILED, "mmap");
+ memset(dest_mapping, 'X', 10 * page_size);
+
+ // We will grab the last 5 pages of the source and move them.
+ void *remapped_mapping =
+ mremap(source_mapping, 5 * page_size,
+ 5 * page_size,
+ MREMAP_DONTUNMAP | MREMAP_MAYMOVE | MREMAP_FIXED, dest_mapping);
+ BUG_ON(dest_mapping == MAP_FAILED, "mremap");
+ BUG_ON(dest_mapping != remapped_mapping, "expected to remap to dest_mapping");
+
+ BUG_ON(check_region_contains_byte(source_mapping, 5 * page_size, 0) !=
+ 0, "first 5 pages of source should have no ptes");
+
+ // Finally we expect the destination to have 5 pages worth of a's.
+ BUG_ON(check_region_contains_byte(dest_mapping, 5 * page_size, 'a') != 0,
+ "dest mapping should contain ptes from the source");
+
+ // Finally the last 5 pages shouldn't have been touched.
+ BUG_ON(check_region_contains_byte(dest_mapping + (5 * page_size),
+ 5 * page_size, 'X') != 0,
+ "dest mapping should have retained the last 5 pages");
+
+ BUG_ON(munmap(dest_mapping, 10 * page_size) == -1,
+ "unable to unmap destination mapping");
+ BUG_ON(munmap(source_mapping, 5 * page_size) == -1,
+ "unable to unmap source mapping");
+}
+
+int main(void)
+{
+ page_size = sysconf(_SC_PAGE_SIZE);
+
+ // test for kernel support for MREMAP_DONTUNMAP skipping the test if
+ // not.
+ if (kernel_support_for_mremap_dontunmap() != 0) {
+ printf("No kernel support for MREMAP_DONTUNMAP\n");
+ return KSFT_SKIP;
+ }
+
+ // Keep a page sized buffer around for when we need it.
+ page_buffer =
+ mmap(NULL, page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ BUG_ON(page_buffer == MAP_FAILED, "unable to mmap a page.");
+
+ mremap_dontunmap_simple();
+ mremap_dontunmap_simple_shmem();
+ mremap_dontunmap_simple_fixed();
+ mremap_dontunmap_partial_mapping();
+ mremap_dontunmap_partial_mapping_overwrite();
+
+ BUG_ON(munmap(page_buffer, page_size) == -1,
+ "unable to unmap page buffer");
+
+ printf("OK\n");
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c
new file mode 100644
index 000000000000..5c3773de9f0f
--- /dev/null
+++ b/tools/testing/selftests/mm/mremap_test.c
@@ -0,0 +1,548 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2020 Google LLC
+ */
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <time.h>
+#include <stdbool.h>
+
+#include "../kselftest.h"
+
+#define EXPECT_SUCCESS 0
+#define EXPECT_FAILURE 1
+#define NON_OVERLAPPING 0
+#define OVERLAPPING 1
+#define NS_PER_SEC 1000000000ULL
+#define VALIDATION_DEFAULT_THRESHOLD 4 /* 4MB */
+#define VALIDATION_NO_THRESHOLD 0 /* Verify the entire region */
+
+#define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
+
+struct config {
+ unsigned long long src_alignment;
+ unsigned long long dest_alignment;
+ unsigned long long region_size;
+ int overlapping;
+};
+
+struct test {
+ const char *name;
+ struct config config;
+ int expect_failure;
+};
+
+enum {
+ _1KB = 1ULL << 10, /* 1KB -> not page aligned */
+ _4KB = 4ULL << 10,
+ _8KB = 8ULL << 10,
+ _1MB = 1ULL << 20,
+ _2MB = 2ULL << 20,
+ _4MB = 4ULL << 20,
+ _1GB = 1ULL << 30,
+ _2GB = 2ULL << 30,
+ PMD = _2MB,
+ PUD = _1GB,
+};
+
+#define PTE page_size
+
+#define MAKE_TEST(source_align, destination_align, size, \
+ overlaps, should_fail, test_name) \
+(struct test){ \
+ .name = test_name, \
+ .config = { \
+ .src_alignment = source_align, \
+ .dest_alignment = destination_align, \
+ .region_size = size, \
+ .overlapping = overlaps, \
+ }, \
+ .expect_failure = should_fail \
+}
+
+/*
+ * Returns false if the requested remap region overlaps with an
+ * existing mapping (e.g text, stack) else returns true.
+ */
+static bool is_remap_region_valid(void *addr, unsigned long long size)
+{
+ void *remap_addr = NULL;
+ bool ret = true;
+
+ /* Use MAP_FIXED_NOREPLACE flag to ensure region is not mapped */
+ remap_addr = mmap(addr, size, PROT_READ | PROT_WRITE,
+ MAP_FIXED_NOREPLACE | MAP_ANONYMOUS | MAP_SHARED,
+ -1, 0);
+
+ if (remap_addr == MAP_FAILED) {
+ if (errno == EEXIST)
+ ret = false;
+ } else {
+ munmap(remap_addr, size);
+ }
+
+ return ret;
+}
+
+/* Returns mmap_min_addr sysctl tunable from procfs */
+static unsigned long long get_mmap_min_addr(void)
+{
+ FILE *fp;
+ int n_matched;
+ static unsigned long long addr;
+
+ if (addr)
+ return addr;
+
+ fp = fopen("/proc/sys/vm/mmap_min_addr", "r");
+ if (fp == NULL) {
+ ksft_print_msg("Failed to open /proc/sys/vm/mmap_min_addr: %s\n",
+ strerror(errno));
+ exit(KSFT_SKIP);
+ }
+
+ n_matched = fscanf(fp, "%llu", &addr);
+ if (n_matched != 1) {
+ ksft_print_msg("Failed to read /proc/sys/vm/mmap_min_addr: %s\n",
+ strerror(errno));
+ fclose(fp);
+ exit(KSFT_SKIP);
+ }
+
+ fclose(fp);
+ return addr;
+}
+
+/*
+ * Using /proc/self/maps, assert that the specified address range is contained
+ * within a single mapping.
+ */
+static bool is_range_mapped(FILE *maps_fp, void *start, void *end)
+{
+ char *line = NULL;
+ size_t len = 0;
+ bool success = false;
+
+ rewind(maps_fp);
+
+ while (getline(&line, &len, maps_fp) != -1) {
+ char *first = strtok(line, "- ");
+ void *first_val = (void *)strtol(first, NULL, 16);
+ char *second = strtok(NULL, "- ");
+ void *second_val = (void *) strtol(second, NULL, 16);
+
+ if (first_val <= start && second_val >= end) {
+ success = true;
+ break;
+ }
+ }
+
+ return success;
+}
+
+/*
+ * This test validates that merge is called when expanding a mapping.
+ * Mapping containing three pages is created, middle page is unmapped
+ * and then the mapping containing the first page is expanded so that
+ * it fills the created hole. The two parts should merge creating
+ * single mapping with three pages.
+ */
+static void mremap_expand_merge(FILE *maps_fp, unsigned long page_size)
+{
+ char *test_name = "mremap expand merge";
+ bool success = false;
+ char *remap, *start;
+
+ start = mmap(NULL, 3 * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+ if (start == MAP_FAILED) {
+ ksft_print_msg("mmap failed: %s\n", strerror(errno));
+ goto out;
+ }
+
+ munmap(start + page_size, page_size);
+ remap = mremap(start, page_size, 2 * page_size, 0);
+ if (remap == MAP_FAILED) {
+ ksft_print_msg("mremap failed: %s\n", strerror(errno));
+ munmap(start, page_size);
+ munmap(start + 2 * page_size, page_size);
+ goto out;
+ }
+
+ success = is_range_mapped(maps_fp, start, start + 3 * page_size);
+ munmap(start, 3 * page_size);
+
+out:
+ if (success)
+ ksft_test_result_pass("%s\n", test_name);
+ else
+ ksft_test_result_fail("%s\n", test_name);
+}
+
+/*
+ * Similar to mremap_expand_merge() except instead of removing the middle page,
+ * we remove the last then attempt to remap offset from the second page. This
+ * should result in the mapping being restored to its former state.
+ */
+static void mremap_expand_merge_offset(FILE *maps_fp, unsigned long page_size)
+{
+
+ char *test_name = "mremap expand merge offset";
+ bool success = false;
+ char *remap, *start;
+
+ start = mmap(NULL, 3 * page_size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+ if (start == MAP_FAILED) {
+ ksft_print_msg("mmap failed: %s\n", strerror(errno));
+ goto out;
+ }
+
+ /* Unmap final page to ensure we have space to expand. */
+ munmap(start + 2 * page_size, page_size);
+ remap = mremap(start + page_size, page_size, 2 * page_size, 0);
+ if (remap == MAP_FAILED) {
+ ksft_print_msg("mremap failed: %s\n", strerror(errno));
+ munmap(start, 2 * page_size);
+ goto out;
+ }
+
+ success = is_range_mapped(maps_fp, start, start + 3 * page_size);
+ munmap(start, 3 * page_size);
+
+out:
+ if (success)
+ ksft_test_result_pass("%s\n", test_name);
+ else
+ ksft_test_result_fail("%s\n", test_name);
+}
+
+/*
+ * Returns the start address of the mapping on success, else returns
+ * NULL on failure.
+ */
+static void *get_source_mapping(struct config c)
+{
+ unsigned long long addr = 0ULL;
+ void *src_addr = NULL;
+ unsigned long long mmap_min_addr;
+
+ mmap_min_addr = get_mmap_min_addr();
+
+retry:
+ addr += c.src_alignment;
+ if (addr < mmap_min_addr)
+ goto retry;
+
+ src_addr = mmap((void *) addr, c.region_size, PROT_READ | PROT_WRITE,
+ MAP_FIXED_NOREPLACE | MAP_ANONYMOUS | MAP_SHARED,
+ -1, 0);
+ if (src_addr == MAP_FAILED) {
+ if (errno == EPERM || errno == EEXIST)
+ goto retry;
+ goto error;
+ }
+ /*
+ * Check that the address is aligned to the specified alignment.
+ * Addresses which have alignments that are multiples of that
+ * specified are not considered valid. For instance, 1GB address is
+ * 2MB-aligned, however it will not be considered valid for a
+ * requested alignment of 2MB. This is done to reduce coincidental
+ * alignment in the tests.
+ */
+ if (((unsigned long long) src_addr & (c.src_alignment - 1)) ||
+ !((unsigned long long) src_addr & c.src_alignment)) {
+ munmap(src_addr, c.region_size);
+ goto retry;
+ }
+
+ if (!src_addr)
+ goto error;
+
+ return src_addr;
+error:
+ ksft_print_msg("Failed to map source region: %s\n",
+ strerror(errno));
+ return NULL;
+}
+
+/* Returns the time taken for the remap on success else returns -1. */
+static long long remap_region(struct config c, unsigned int threshold_mb,
+ char pattern_seed)
+{
+ void *addr, *src_addr, *dest_addr;
+ unsigned long long i;
+ struct timespec t_start = {0, 0}, t_end = {0, 0};
+ long long start_ns, end_ns, align_mask, ret, offset;
+ unsigned long long threshold;
+
+ if (threshold_mb == VALIDATION_NO_THRESHOLD)
+ threshold = c.region_size;
+ else
+ threshold = MIN(threshold_mb * _1MB, c.region_size);
+
+ src_addr = get_source_mapping(c);
+ if (!src_addr) {
+ ret = -1;
+ goto out;
+ }
+
+ /* Set byte pattern */
+ srand(pattern_seed);
+ for (i = 0; i < threshold; i++)
+ memset((char *) src_addr + i, (char) rand(), 1);
+
+ /* Mask to zero out lower bits of address for alignment */
+ align_mask = ~(c.dest_alignment - 1);
+ /* Offset of destination address from the end of the source region */
+ offset = (c.overlapping) ? -c.dest_alignment : c.dest_alignment;
+ addr = (void *) (((unsigned long long) src_addr + c.region_size
+ + offset) & align_mask);
+
+ /* See comment in get_source_mapping() */
+ if (!((unsigned long long) addr & c.dest_alignment))
+ addr = (void *) ((unsigned long long) addr | c.dest_alignment);
+
+ /* Don't destroy existing mappings unless expected to overlap */
+ while (!is_remap_region_valid(addr, c.region_size) && !c.overlapping) {
+ /* Check for unsigned overflow */
+ if (addr + c.dest_alignment < addr) {
+ ksft_print_msg("Couldn't find a valid region to remap to\n");
+ ret = -1;
+ goto out;
+ }
+ addr += c.dest_alignment;
+ }
+
+ clock_gettime(CLOCK_MONOTONIC, &t_start);
+ dest_addr = mremap(src_addr, c.region_size, c.region_size,
+ MREMAP_MAYMOVE|MREMAP_FIXED, (char *) addr);
+ clock_gettime(CLOCK_MONOTONIC, &t_end);
+
+ if (dest_addr == MAP_FAILED) {
+ ksft_print_msg("mremap failed: %s\n", strerror(errno));
+ ret = -1;
+ goto clean_up_src;
+ }
+
+ /* Verify byte pattern after remapping */
+ srand(pattern_seed);
+ for (i = 0; i < threshold; i++) {
+ char c = (char) rand();
+
+ if (((char *) dest_addr)[i] != c) {
+ ksft_print_msg("Data after remap doesn't match at offset %d\n",
+ i);
+ ksft_print_msg("Expected: %#x\t Got: %#x\n", c & 0xff,
+ ((char *) dest_addr)[i] & 0xff);
+ ret = -1;
+ goto clean_up_dest;
+ }
+ }
+
+ start_ns = t_start.tv_sec * NS_PER_SEC + t_start.tv_nsec;
+ end_ns = t_end.tv_sec * NS_PER_SEC + t_end.tv_nsec;
+ ret = end_ns - start_ns;
+
+/*
+ * Since the destination address is specified using MREMAP_FIXED, subsequent
+ * mremap will unmap any previous mapping at the address range specified by
+ * dest_addr and region_size. This significantly affects the remap time of
+ * subsequent tests. So we clean up mappings after each test.
+ */
+clean_up_dest:
+ munmap(dest_addr, c.region_size);
+clean_up_src:
+ munmap(src_addr, c.region_size);
+out:
+ return ret;
+}
+
+static void run_mremap_test_case(struct test test_case, int *failures,
+ unsigned int threshold_mb,
+ unsigned int pattern_seed)
+{
+ long long remap_time = remap_region(test_case.config, threshold_mb,
+ pattern_seed);
+
+ if (remap_time < 0) {
+ if (test_case.expect_failure)
+ ksft_test_result_xfail("%s\n\tExpected mremap failure\n",
+ test_case.name);
+ else {
+ ksft_test_result_fail("%s\n", test_case.name);
+ *failures += 1;
+ }
+ } else {
+ /*
+ * Comparing mremap time is only applicable if entire region
+ * was faulted in.
+ */
+ if (threshold_mb == VALIDATION_NO_THRESHOLD ||
+ test_case.config.region_size <= threshold_mb * _1MB)
+ ksft_test_result_pass("%s\n\tmremap time: %12lldns\n",
+ test_case.name, remap_time);
+ else
+ ksft_test_result_pass("%s\n", test_case.name);
+ }
+}
+
+static void usage(const char *cmd)
+{
+ fprintf(stderr,
+ "Usage: %s [[-t <threshold_mb>] [-p <pattern_seed>]]\n"
+ "-t\t only validate threshold_mb of the remapped region\n"
+ " \t if 0 is supplied no threshold is used; all tests\n"
+ " \t are run and remapped regions validated fully.\n"
+ " \t The default threshold used is 4MB.\n"
+ "-p\t provide a seed to generate the random pattern for\n"
+ " \t validating the remapped region.\n", cmd);
+}
+
+static int parse_args(int argc, char **argv, unsigned int *threshold_mb,
+ unsigned int *pattern_seed)
+{
+ const char *optstr = "t:p:";
+ int opt;
+
+ while ((opt = getopt(argc, argv, optstr)) != -1) {
+ switch (opt) {
+ case 't':
+ *threshold_mb = atoi(optarg);
+ break;
+ case 'p':
+ *pattern_seed = atoi(optarg);
+ break;
+ default:
+ usage(argv[0]);
+ return -1;
+ }
+ }
+
+ if (optind < argc) {
+ usage(argv[0]);
+ return -1;
+ }
+
+ return 0;
+}
+
+#define MAX_TEST 13
+#define MAX_PERF_TEST 3
+int main(int argc, char **argv)
+{
+ int failures = 0;
+ int i, run_perf_tests;
+ unsigned int threshold_mb = VALIDATION_DEFAULT_THRESHOLD;
+ unsigned int pattern_seed;
+ int num_expand_tests = 2;
+ struct test test_cases[MAX_TEST];
+ struct test perf_test_cases[MAX_PERF_TEST];
+ int page_size;
+ time_t t;
+ FILE *maps_fp;
+
+ pattern_seed = (unsigned int) time(&t);
+
+ if (parse_args(argc, argv, &threshold_mb, &pattern_seed) < 0)
+ exit(EXIT_FAILURE);
+
+ ksft_print_msg("Test configs:\n\tthreshold_mb=%u\n\tpattern_seed=%u\n\n",
+ threshold_mb, pattern_seed);
+
+ page_size = sysconf(_SC_PAGESIZE);
+
+ /* Expected mremap failures */
+ test_cases[0] = MAKE_TEST(page_size, page_size, page_size,
+ OVERLAPPING, EXPECT_FAILURE,
+ "mremap - Source and Destination Regions Overlapping");
+
+ test_cases[1] = MAKE_TEST(page_size, page_size/4, page_size,
+ NON_OVERLAPPING, EXPECT_FAILURE,
+ "mremap - Destination Address Misaligned (1KB-aligned)");
+ test_cases[2] = MAKE_TEST(page_size/4, page_size, page_size,
+ NON_OVERLAPPING, EXPECT_FAILURE,
+ "mremap - Source Address Misaligned (1KB-aligned)");
+
+ /* Src addr PTE aligned */
+ test_cases[3] = MAKE_TEST(PTE, PTE, PTE * 2,
+ NON_OVERLAPPING, EXPECT_SUCCESS,
+ "8KB mremap - Source PTE-aligned, Destination PTE-aligned");
+
+ /* Src addr 1MB aligned */
+ test_cases[4] = MAKE_TEST(_1MB, PTE, _2MB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "2MB mremap - Source 1MB-aligned, Destination PTE-aligned");
+ test_cases[5] = MAKE_TEST(_1MB, _1MB, _2MB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "2MB mremap - Source 1MB-aligned, Destination 1MB-aligned");
+
+ /* Src addr PMD aligned */
+ test_cases[6] = MAKE_TEST(PMD, PTE, _4MB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "4MB mremap - Source PMD-aligned, Destination PTE-aligned");
+ test_cases[7] = MAKE_TEST(PMD, _1MB, _4MB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "4MB mremap - Source PMD-aligned, Destination 1MB-aligned");
+ test_cases[8] = MAKE_TEST(PMD, PMD, _4MB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "4MB mremap - Source PMD-aligned, Destination PMD-aligned");
+
+ /* Src addr PUD aligned */
+ test_cases[9] = MAKE_TEST(PUD, PTE, _2GB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "2GB mremap - Source PUD-aligned, Destination PTE-aligned");
+ test_cases[10] = MAKE_TEST(PUD, _1MB, _2GB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "2GB mremap - Source PUD-aligned, Destination 1MB-aligned");
+ test_cases[11] = MAKE_TEST(PUD, PMD, _2GB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "2GB mremap - Source PUD-aligned, Destination PMD-aligned");
+ test_cases[12] = MAKE_TEST(PUD, PUD, _2GB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "2GB mremap - Source PUD-aligned, Destination PUD-aligned");
+
+ perf_test_cases[0] = MAKE_TEST(page_size, page_size, _1GB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "1GB mremap - Source PTE-aligned, Destination PTE-aligned");
+ /*
+ * mremap 1GB region - Page table level aligned time
+ * comparison.
+ */
+ perf_test_cases[1] = MAKE_TEST(PMD, PMD, _1GB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "1GB mremap - Source PMD-aligned, Destination PMD-aligned");
+ perf_test_cases[2] = MAKE_TEST(PUD, PUD, _1GB, NON_OVERLAPPING, EXPECT_SUCCESS,
+ "1GB mremap - Source PUD-aligned, Destination PUD-aligned");
+
+ run_perf_tests = (threshold_mb == VALIDATION_NO_THRESHOLD) ||
+ (threshold_mb * _1MB >= _1GB);
+
+ ksft_set_plan(ARRAY_SIZE(test_cases) + (run_perf_tests ?
+ ARRAY_SIZE(perf_test_cases) : 0) + num_expand_tests);
+
+ for (i = 0; i < ARRAY_SIZE(test_cases); i++)
+ run_mremap_test_case(test_cases[i], &failures, threshold_mb,
+ pattern_seed);
+
+ maps_fp = fopen("/proc/self/maps", "r");
+
+ if (maps_fp == NULL) {
+ ksft_print_msg("Failed to read /proc/self/maps: %s\n", strerror(errno));
+ exit(KSFT_FAIL);
+ }
+
+ mremap_expand_merge(maps_fp, page_size);
+ mremap_expand_merge_offset(maps_fp, page_size);
+
+ fclose(maps_fp);
+
+ if (run_perf_tests) {
+ ksft_print_msg("\n%s\n",
+ "mremap HAVE_MOVE_PMD/PUD optimization time comparison for 1GB region:");
+ for (i = 0; i < ARRAY_SIZE(perf_test_cases); i++)
+ run_mremap_test_case(perf_test_cases[i], &failures,
+ threshold_mb, pattern_seed);
+ }
+
+ if (failures > 0)
+ ksft_exit_fail();
+ else
+ ksft_exit_pass();
+}
diff --git a/tools/testing/selftests/mm/on-fault-limit.c b/tools/testing/selftests/mm/on-fault-limit.c
new file mode 100644
index 000000000000..634d87dfb2a4
--- /dev/null
+++ b/tools/testing/selftests/mm/on-fault-limit.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <sys/mman.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/time.h>
+#include <sys/resource.h>
+
+#ifndef MCL_ONFAULT
+#define MCL_ONFAULT (MCL_FUTURE << 1)
+#endif
+
+static int test_limit(void)
+{
+ int ret = 1;
+ struct rlimit lims;
+ void *map;
+
+ if (getrlimit(RLIMIT_MEMLOCK, &lims)) {
+ perror("getrlimit");
+ return ret;
+ }
+
+ if (mlockall(MCL_ONFAULT | MCL_FUTURE)) {
+ perror("mlockall");
+ return ret;
+ }
+
+ map = mmap(NULL, 2 * lims.rlim_max, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS | MAP_POPULATE, -1, 0);
+ if (map != MAP_FAILED)
+ printf("mmap should have failed, but didn't\n");
+ else {
+ ret = 0;
+ munmap(map, 2 * lims.rlim_max);
+ }
+
+ munlockall();
+ return ret;
+}
+
+int main(int argc, char **argv)
+{
+ int ret = 0;
+
+ ret += test_limit();
+ return ret;
+}
diff --git a/tools/testing/selftests/mm/pkey-helpers.h b/tools/testing/selftests/mm/pkey-helpers.h
new file mode 100644
index 000000000000..92f3be3dd8e5
--- /dev/null
+++ b/tools/testing/selftests/mm/pkey-helpers.h
@@ -0,0 +1,226 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _PKEYS_HELPER_H
+#define _PKEYS_HELPER_H
+#define _GNU_SOURCE
+#include <string.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+
+#include "../kselftest.h"
+
+/* Define some kernel-like types */
+#define u8 __u8
+#define u16 __u16
+#define u32 __u32
+#define u64 __u64
+
+#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
+
+#ifndef DEBUG_LEVEL
+#define DEBUG_LEVEL 0
+#endif
+#define DPRINT_IN_SIGNAL_BUF_SIZE 4096
+extern int dprint_in_signal;
+extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
+
+extern int test_nr;
+extern int iteration_nr;
+
+#ifdef __GNUC__
+__attribute__((format(printf, 1, 2)))
+#endif
+static inline void sigsafe_printf(const char *format, ...)
+{
+ va_list ap;
+
+ if (!dprint_in_signal) {
+ va_start(ap, format);
+ vprintf(format, ap);
+ va_end(ap);
+ } else {
+ int ret;
+ /*
+ * No printf() functions are signal-safe.
+ * They deadlock easily. Write the format
+ * string to get some output, even if
+ * incomplete.
+ */
+ ret = write(1, format, strlen(format));
+ if (ret < 0)
+ exit(1);
+ }
+}
+#define dprintf_level(level, args...) do { \
+ if (level <= DEBUG_LEVEL) \
+ sigsafe_printf(args); \
+} while (0)
+#define dprintf0(args...) dprintf_level(0, args)
+#define dprintf1(args...) dprintf_level(1, args)
+#define dprintf2(args...) dprintf_level(2, args)
+#define dprintf3(args...) dprintf_level(3, args)
+#define dprintf4(args...) dprintf_level(4, args)
+
+extern void abort_hooks(void);
+#define pkey_assert(condition) do { \
+ if (!(condition)) { \
+ dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
+ __FILE__, __LINE__, \
+ test_nr, iteration_nr); \
+ dprintf0("errno at assert: %d", errno); \
+ abort_hooks(); \
+ exit(__LINE__); \
+ } \
+} while (0)
+
+__attribute__((noinline)) int read_ptr(int *ptr);
+void expected_pkey_fault(int pkey);
+int sys_pkey_alloc(unsigned long flags, unsigned long init_val);
+int sys_pkey_free(unsigned long pkey);
+int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
+ unsigned long pkey);
+void record_pkey_malloc(void *ptr, long size, int prot);
+
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+#include "pkey-x86.h"
+#elif defined(__powerpc64__) /* arch */
+#include "pkey-powerpc.h"
+#else /* arch */
+#error Architecture not supported
+#endif /* arch */
+
+#define PKEY_MASK (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)
+
+static inline u64 set_pkey_bits(u64 reg, int pkey, u64 flags)
+{
+ u32 shift = pkey_bit_position(pkey);
+ /* mask out bits from pkey in old value */
+ reg &= ~((u64)PKEY_MASK << shift);
+ /* OR in new bits for pkey */
+ reg |= (flags & PKEY_MASK) << shift;
+ return reg;
+}
+
+static inline u64 get_pkey_bits(u64 reg, int pkey)
+{
+ u32 shift = pkey_bit_position(pkey);
+ /*
+ * shift down the relevant bits to the lowest two, then
+ * mask off all the other higher bits
+ */
+ return ((reg >> shift) & PKEY_MASK);
+}
+
+extern u64 shadow_pkey_reg;
+
+static inline u64 _read_pkey_reg(int line)
+{
+ u64 pkey_reg = __read_pkey_reg();
+
+ dprintf4("read_pkey_reg(line=%d) pkey_reg: %016llx"
+ " shadow: %016llx\n",
+ line, pkey_reg, shadow_pkey_reg);
+ assert(pkey_reg == shadow_pkey_reg);
+
+ return pkey_reg;
+}
+
+#define read_pkey_reg() _read_pkey_reg(__LINE__)
+
+static inline void write_pkey_reg(u64 pkey_reg)
+{
+ dprintf4("%s() changing %016llx to %016llx\n", __func__,
+ __read_pkey_reg(), pkey_reg);
+ /* will do the shadow check for us: */
+ read_pkey_reg();
+ __write_pkey_reg(pkey_reg);
+ shadow_pkey_reg = pkey_reg;
+ dprintf4("%s(%016llx) pkey_reg: %016llx\n", __func__,
+ pkey_reg, __read_pkey_reg());
+}
+
+/*
+ * These are technically racy. since something could
+ * change PKEY register between the read and the write.
+ */
+static inline void __pkey_access_allow(int pkey, int do_allow)
+{
+ u64 pkey_reg = read_pkey_reg();
+ int bit = pkey * 2;
+
+ if (do_allow)
+ pkey_reg &= (1<<bit);
+ else
+ pkey_reg |= (1<<bit);
+
+ dprintf4("pkey_reg now: %016llx\n", read_pkey_reg());
+ write_pkey_reg(pkey_reg);
+}
+
+static inline void __pkey_write_allow(int pkey, int do_allow_write)
+{
+ u64 pkey_reg = read_pkey_reg();
+ int bit = pkey * 2 + 1;
+
+ if (do_allow_write)
+ pkey_reg &= (1<<bit);
+ else
+ pkey_reg |= (1<<bit);
+
+ write_pkey_reg(pkey_reg);
+ dprintf4("pkey_reg now: %016llx\n", read_pkey_reg());
+}
+
+#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))
+#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
+#define ALIGN_PTR_UP(p, ptr_align_to) \
+ ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
+#define ALIGN_PTR_DOWN(p, ptr_align_to) \
+ ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
+#define __stringify_1(x...) #x
+#define __stringify(x...) __stringify_1(x)
+
+static inline u32 *siginfo_get_pkey_ptr(siginfo_t *si)
+{
+#ifdef si_pkey
+ return &si->si_pkey;
+#else
+ return (u32 *)(((u8 *)si) + si_pkey_offset);
+#endif
+}
+
+static inline int kernel_has_pkeys(void)
+{
+ /* try allocating a key and see if it succeeds */
+ int ret = sys_pkey_alloc(0, 0);
+ if (ret <= 0) {
+ return 0;
+ }
+ sys_pkey_free(ret);
+ return 1;
+}
+
+static inline int is_pkeys_supported(void)
+{
+ /* check if the cpu supports pkeys */
+ if (!cpu_has_pkeys()) {
+ dprintf1("SKIP: %s: no CPU support\n", __func__);
+ return 0;
+ }
+
+ /* check if the kernel supports pkeys */
+ if (!kernel_has_pkeys()) {
+ dprintf1("SKIP: %s: no kernel support\n", __func__);
+ return 0;
+ }
+
+ return 1;
+}
+
+#endif /* _PKEYS_HELPER_H */
diff --git a/tools/testing/selftests/mm/pkey-powerpc.h b/tools/testing/selftests/mm/pkey-powerpc.h
new file mode 100644
index 000000000000..1ebb586b2fbc
--- /dev/null
+++ b/tools/testing/selftests/mm/pkey-powerpc.h
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _PKEYS_POWERPC_H
+#define _PKEYS_POWERPC_H
+
+#ifndef SYS_mprotect_key
+# define SYS_mprotect_key 386
+#endif
+#ifndef SYS_pkey_alloc
+# define SYS_pkey_alloc 384
+# define SYS_pkey_free 385
+#endif
+#define REG_IP_IDX PT_NIP
+#define REG_TRAPNO PT_TRAP
+#define gregs gp_regs
+#define fpregs fp_regs
+#define si_pkey_offset 0x20
+
+#undef PKEY_DISABLE_ACCESS
+#define PKEY_DISABLE_ACCESS 0x3 /* disable read and write */
+
+#undef PKEY_DISABLE_WRITE
+#define PKEY_DISABLE_WRITE 0x2
+
+#define NR_PKEYS 32
+#define NR_RESERVED_PKEYS_4K 27 /* pkey-0, pkey-1, exec-only-pkey
+ and 24 other keys that cannot be
+ represented in the PTE */
+#define NR_RESERVED_PKEYS_64K_3KEYS 3 /* PowerNV and KVM: pkey-0,
+ pkey-1 and exec-only key */
+#define NR_RESERVED_PKEYS_64K_4KEYS 4 /* PowerVM: pkey-0, pkey-1,
+ pkey-31 and exec-only key */
+#define PKEY_BITS_PER_PKEY 2
+#define HPAGE_SIZE (1UL << 24)
+#define PAGE_SIZE sysconf(_SC_PAGESIZE)
+
+static inline u32 pkey_bit_position(int pkey)
+{
+ return (NR_PKEYS - pkey - 1) * PKEY_BITS_PER_PKEY;
+}
+
+static inline u64 __read_pkey_reg(void)
+{
+ u64 pkey_reg;
+
+ asm volatile("mfspr %0, 0xd" : "=r" (pkey_reg));
+
+ return pkey_reg;
+}
+
+static inline void __write_pkey_reg(u64 pkey_reg)
+{
+ u64 amr = pkey_reg;
+
+ dprintf4("%s() changing %016llx to %016llx\n",
+ __func__, __read_pkey_reg(), pkey_reg);
+
+ asm volatile("isync; mtspr 0xd, %0; isync"
+ : : "r" ((unsigned long)(amr)) : "memory");
+
+ dprintf4("%s() pkey register after changing %016llx to %016llx\n",
+ __func__, __read_pkey_reg(), pkey_reg);
+}
+
+static inline int cpu_has_pkeys(void)
+{
+ /* No simple way to determine this */
+ return 1;
+}
+
+static inline bool arch_is_powervm()
+{
+ struct stat buf;
+
+ if ((stat("/sys/firmware/devicetree/base/ibm,partition-name", &buf) == 0) &&
+ (stat("/sys/firmware/devicetree/base/hmc-managed?", &buf) == 0) &&
+ (stat("/sys/firmware/devicetree/base/chosen/qemu,graphic-width", &buf) == -1) )
+ return true;
+
+ return false;
+}
+
+static inline int get_arch_reserved_keys(void)
+{
+ if (sysconf(_SC_PAGESIZE) == 4096)
+ return NR_RESERVED_PKEYS_4K;
+ else
+ if (arch_is_powervm())
+ return NR_RESERVED_PKEYS_64K_4KEYS;
+ else
+ return NR_RESERVED_PKEYS_64K_3KEYS;
+}
+
+void expect_fault_on_read_execonly_key(void *p1, int pkey)
+{
+ /*
+ * powerpc does not allow userspace to change permissions of exec-only
+ * keys since those keys are not allocated by userspace. The signal
+ * handler wont be able to reset the permissions, which means the code
+ * will infinitely continue to segfault here.
+ */
+ return;
+}
+
+/* 4-byte instructions * 16384 = 64K page */
+#define __page_o_noops() asm(".rept 16384 ; nop; .endr")
+
+void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey)
+{
+ void *ptr;
+ int ret;
+
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ pkey_assert(pkey < NR_PKEYS);
+ ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+
+ ret = syscall(__NR_subpage_prot, ptr, size, NULL);
+ if (ret) {
+ perror("subpage_perm");
+ return PTR_ERR_ENOTSUP;
+ }
+
+ ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
+ pkey_assert(!ret);
+ record_pkey_malloc(ptr, size, prot);
+
+ dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
+ return ptr;
+}
+
+#endif /* _PKEYS_POWERPC_H */
diff --git a/tools/testing/selftests/mm/pkey-x86.h b/tools/testing/selftests/mm/pkey-x86.h
new file mode 100644
index 000000000000..72c14cd3ddc7
--- /dev/null
+++ b/tools/testing/selftests/mm/pkey-x86.h
@@ -0,0 +1,177 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _PKEYS_X86_H
+#define _PKEYS_X86_H
+
+#ifdef __i386__
+
+#ifndef SYS_mprotect_key
+# define SYS_mprotect_key 380
+#endif
+
+#ifndef SYS_pkey_alloc
+# define SYS_pkey_alloc 381
+# define SYS_pkey_free 382
+#endif
+
+#define REG_IP_IDX REG_EIP
+#define si_pkey_offset 0x14
+
+#else
+
+#ifndef SYS_mprotect_key
+# define SYS_mprotect_key 329
+#endif
+
+#ifndef SYS_pkey_alloc
+# define SYS_pkey_alloc 330
+# define SYS_pkey_free 331
+#endif
+
+#define REG_IP_IDX REG_RIP
+#define si_pkey_offset 0x20
+
+#endif
+
+#ifndef PKEY_DISABLE_ACCESS
+# define PKEY_DISABLE_ACCESS 0x1
+#endif
+
+#ifndef PKEY_DISABLE_WRITE
+# define PKEY_DISABLE_WRITE 0x2
+#endif
+
+#define NR_PKEYS 16
+#define NR_RESERVED_PKEYS 2 /* pkey-0 and exec-only-pkey */
+#define PKEY_BITS_PER_PKEY 2
+#define HPAGE_SIZE (1UL<<21)
+#define PAGE_SIZE 4096
+#define MB (1<<20)
+
+static inline void __page_o_noops(void)
+{
+ /* 8-bytes of instruction * 512 bytes = 1 page */
+ asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
+}
+
+static inline u64 __read_pkey_reg(void)
+{
+ unsigned int eax, edx;
+ unsigned int ecx = 0;
+ unsigned pkey_reg;
+
+ asm volatile(".byte 0x0f,0x01,0xee\n\t"
+ : "=a" (eax), "=d" (edx)
+ : "c" (ecx));
+ pkey_reg = eax;
+ return pkey_reg;
+}
+
+static inline void __write_pkey_reg(u64 pkey_reg)
+{
+ unsigned int eax = pkey_reg;
+ unsigned int ecx = 0;
+ unsigned int edx = 0;
+
+ dprintf4("%s() changing %016llx to %016llx\n", __func__,
+ __read_pkey_reg(), pkey_reg);
+ asm volatile(".byte 0x0f,0x01,0xef\n\t"
+ : : "a" (eax), "c" (ecx), "d" (edx));
+ assert(pkey_reg == __read_pkey_reg());
+}
+
+/* Intel-defined CPU features, CPUID level 0x00000007:0 (ecx) */
+#define X86_FEATURE_PKU (1<<3) /* Protection Keys for Userspace */
+#define X86_FEATURE_OSPKE (1<<4) /* OS Protection Keys Enable */
+
+static inline int cpu_has_pkeys(void)
+{
+ unsigned int eax;
+ unsigned int ebx;
+ unsigned int ecx;
+ unsigned int edx;
+
+ __cpuid_count(0x7, 0x0, eax, ebx, ecx, edx);
+
+ if (!(ecx & X86_FEATURE_PKU)) {
+ dprintf2("cpu does not have PKU\n");
+ return 0;
+ }
+ if (!(ecx & X86_FEATURE_OSPKE)) {
+ dprintf2("cpu does not have OSPKE\n");
+ return 0;
+ }
+ return 1;
+}
+
+static inline int cpu_max_xsave_size(void)
+{
+ unsigned long XSTATE_CPUID = 0xd;
+ unsigned int eax;
+ unsigned int ebx;
+ unsigned int ecx;
+ unsigned int edx;
+
+ __cpuid_count(XSTATE_CPUID, 0, eax, ebx, ecx, edx);
+ return ecx;
+}
+
+static inline u32 pkey_bit_position(int pkey)
+{
+ return pkey * PKEY_BITS_PER_PKEY;
+}
+
+#define XSTATE_PKEY_BIT (9)
+#define XSTATE_PKEY 0x200
+#define XSTATE_BV_OFFSET 512
+
+int pkey_reg_xstate_offset(void)
+{
+ unsigned int eax;
+ unsigned int ebx;
+ unsigned int ecx;
+ unsigned int edx;
+ int xstate_offset;
+ int xstate_size;
+ unsigned long XSTATE_CPUID = 0xd;
+ int leaf;
+
+ /* assume that XSTATE_PKEY is set in XCR0 */
+ leaf = XSTATE_PKEY_BIT;
+ {
+ __cpuid_count(XSTATE_CPUID, leaf, eax, ebx, ecx, edx);
+
+ if (leaf == XSTATE_PKEY_BIT) {
+ xstate_offset = ebx;
+ xstate_size = eax;
+ }
+ }
+
+ if (xstate_size == 0) {
+ printf("could not find size/offset of PKEY in xsave state\n");
+ return 0;
+ }
+
+ return xstate_offset;
+}
+
+static inline int get_arch_reserved_keys(void)
+{
+ return NR_RESERVED_PKEYS;
+}
+
+void expect_fault_on_read_execonly_key(void *p1, int pkey)
+{
+ int ptr_contents;
+
+ ptr_contents = read_ptr(p1);
+ dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
+ expected_pkey_fault(pkey);
+}
+
+void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey)
+{
+ return PTR_ERR_ENOTSUP;
+}
+
+#endif /* _PKEYS_X86_H */
diff --git a/tools/testing/selftests/mm/protection_keys.c b/tools/testing/selftests/mm/protection_keys.c
new file mode 100644
index 000000000000..95f403a0c46d
--- /dev/null
+++ b/tools/testing/selftests/mm/protection_keys.c
@@ -0,0 +1,1788 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Tests Memory Protection Keys (see Documentation/core-api/protection-keys.rst)
+ *
+ * There are examples in here of:
+ * * how to set protection keys on memory
+ * * how to set/clear bits in pkey registers (the rights register)
+ * * how to handle SEGV_PKUERR signals and extract pkey-relevant
+ * information from the siginfo
+ *
+ * Things to add:
+ * make sure KSM and KSM COW breaking works
+ * prefault pages in at malloc, or not
+ * protect MPX bounds tables with protection keys?
+ * make sure VMA splitting/merging is working correctly
+ * OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
+ * look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
+ * do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
+ *
+ * Compile like this:
+ * gcc -mxsave -o protection_keys -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ * gcc -mxsave -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
+ */
+#define _GNU_SOURCE
+#define __SANE_USERSPACE_TYPES__
+#include <errno.h>
+#include <linux/elf.h>
+#include <linux/futex.h>
+#include <time.h>
+#include <sys/time.h>
+#include <sys/syscall.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <signal.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <ucontext.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/ptrace.h>
+#include <setjmp.h>
+
+#include "pkey-helpers.h"
+
+int iteration_nr = 1;
+int test_nr;
+
+u64 shadow_pkey_reg;
+int dprint_in_signal;
+char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
+
+void cat_into_file(char *str, char *file)
+{
+ int fd = open(file, O_RDWR);
+ int ret;
+
+ dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
+ /*
+ * these need to be raw because they are called under
+ * pkey_assert()
+ */
+ if (fd < 0) {
+ fprintf(stderr, "error opening '%s'\n", str);
+ perror("error: ");
+ exit(__LINE__);
+ }
+
+ ret = write(fd, str, strlen(str));
+ if (ret != strlen(str)) {
+ perror("write to file failed");
+ fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
+ exit(__LINE__);
+ }
+ close(fd);
+}
+
+#if CONTROL_TRACING > 0
+static int warned_tracing;
+int tracing_root_ok(void)
+{
+ if (geteuid() != 0) {
+ if (!warned_tracing)
+ fprintf(stderr, "WARNING: not run as root, "
+ "can not do tracing control\n");
+ warned_tracing = 1;
+ return 0;
+ }
+ return 1;
+}
+#endif
+
+void tracing_on(void)
+{
+#if CONTROL_TRACING > 0
+#define TRACEDIR "/sys/kernel/debug/tracing"
+ char pidstr[32];
+
+ if (!tracing_root_ok())
+ return;
+
+ sprintf(pidstr, "%d", getpid());
+ cat_into_file("0", TRACEDIR "/tracing_on");
+ cat_into_file("\n", TRACEDIR "/trace");
+ if (1) {
+ cat_into_file("function_graph", TRACEDIR "/current_tracer");
+ cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
+ } else {
+ cat_into_file("nop", TRACEDIR "/current_tracer");
+ }
+ cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
+ cat_into_file("1", TRACEDIR "/tracing_on");
+ dprintf1("enabled tracing\n");
+#endif
+}
+
+void tracing_off(void)
+{
+#if CONTROL_TRACING > 0
+ if (!tracing_root_ok())
+ return;
+ cat_into_file("0", "/sys/kernel/debug/tracing/tracing_on");
+#endif
+}
+
+void abort_hooks(void)
+{
+ fprintf(stderr, "running %s()...\n", __func__);
+ tracing_off();
+#ifdef SLEEP_ON_ABORT
+ sleep(SLEEP_ON_ABORT);
+#endif
+}
+
+/*
+ * This attempts to have roughly a page of instructions followed by a few
+ * instructions that do a write, and another page of instructions. That
+ * way, we are pretty sure that the write is in the second page of
+ * instructions and has at least a page of padding behind it.
+ *
+ * *That* lets us be sure to madvise() away the write instruction, which
+ * will then fault, which makes sure that the fault code handles
+ * execute-only memory properly.
+ */
+#ifdef __powerpc64__
+/* This way, both 4K and 64K alignment are maintained */
+__attribute__((__aligned__(65536)))
+#else
+__attribute__((__aligned__(PAGE_SIZE)))
+#endif
+void lots_o_noops_around_write(int *write_to_me)
+{
+ dprintf3("running %s()\n", __func__);
+ __page_o_noops();
+ /* Assume this happens in the second page of instructions: */
+ *write_to_me = __LINE__;
+ /* pad out by another page: */
+ __page_o_noops();
+ dprintf3("%s() done\n", __func__);
+}
+
+void dump_mem(void *dumpme, int len_bytes)
+{
+ char *c = (void *)dumpme;
+ int i;
+
+ for (i = 0; i < len_bytes; i += sizeof(u64)) {
+ u64 *ptr = (u64 *)(c + i);
+ dprintf1("dump[%03d][@%p]: %016llx\n", i, ptr, *ptr);
+ }
+}
+
+static u32 hw_pkey_get(int pkey, unsigned long flags)
+{
+ u64 pkey_reg = __read_pkey_reg();
+
+ dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
+ __func__, pkey, flags, 0, 0);
+ dprintf2("%s() raw pkey_reg: %016llx\n", __func__, pkey_reg);
+
+ return (u32) get_pkey_bits(pkey_reg, pkey);
+}
+
+static int hw_pkey_set(int pkey, unsigned long rights, unsigned long flags)
+{
+ u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
+ u64 old_pkey_reg = __read_pkey_reg();
+ u64 new_pkey_reg;
+
+ /* make sure that 'rights' only contains the bits we expect: */
+ assert(!(rights & ~mask));
+
+ /* modify bits accordingly in old pkey_reg and assign it */
+ new_pkey_reg = set_pkey_bits(old_pkey_reg, pkey, rights);
+
+ __write_pkey_reg(new_pkey_reg);
+
+ dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x"
+ " pkey_reg now: %016llx old_pkey_reg: %016llx\n",
+ __func__, pkey, rights, flags, 0, __read_pkey_reg(),
+ old_pkey_reg);
+ return 0;
+}
+
+void pkey_disable_set(int pkey, int flags)
+{
+ unsigned long syscall_flags = 0;
+ int ret;
+ int pkey_rights;
+ u64 orig_pkey_reg = read_pkey_reg();
+
+ dprintf1("START->%s(%d, 0x%x)\n", __func__,
+ pkey, flags);
+ pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
+
+ pkey_rights = hw_pkey_get(pkey, syscall_flags);
+
+ dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);
+
+ pkey_assert(pkey_rights >= 0);
+
+ pkey_rights |= flags;
+
+ ret = hw_pkey_set(pkey, pkey_rights, syscall_flags);
+ assert(!ret);
+ /* pkey_reg and flags have the same format */
+ shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, pkey, pkey_rights);
+ dprintf1("%s(%d) shadow: 0x%016llx\n",
+ __func__, pkey, shadow_pkey_reg);
+
+ pkey_assert(ret >= 0);
+
+ pkey_rights = hw_pkey_get(pkey, syscall_flags);
+ dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);
+
+ dprintf1("%s(%d) pkey_reg: 0x%016llx\n",
+ __func__, pkey, read_pkey_reg());
+ if (flags)
+ pkey_assert(read_pkey_reg() >= orig_pkey_reg);
+ dprintf1("END<---%s(%d, 0x%x)\n", __func__,
+ pkey, flags);
+}
+
+void pkey_disable_clear(int pkey, int flags)
+{
+ unsigned long syscall_flags = 0;
+ int ret;
+ int pkey_rights = hw_pkey_get(pkey, syscall_flags);
+ u64 orig_pkey_reg = read_pkey_reg();
+
+ pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
+
+ dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);
+ pkey_assert(pkey_rights >= 0);
+
+ pkey_rights &= ~flags;
+
+ ret = hw_pkey_set(pkey, pkey_rights, 0);
+ shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, pkey, pkey_rights);
+ pkey_assert(ret >= 0);
+
+ pkey_rights = hw_pkey_get(pkey, syscall_flags);
+ dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
+ pkey, pkey, pkey_rights);
+
+ dprintf1("%s(%d) pkey_reg: 0x%016llx\n", __func__,
+ pkey, read_pkey_reg());
+ if (flags)
+ assert(read_pkey_reg() <= orig_pkey_reg);
+}
+
+void pkey_write_allow(int pkey)
+{
+ pkey_disable_clear(pkey, PKEY_DISABLE_WRITE);
+}
+void pkey_write_deny(int pkey)
+{
+ pkey_disable_set(pkey, PKEY_DISABLE_WRITE);
+}
+void pkey_access_allow(int pkey)
+{
+ pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS);
+}
+void pkey_access_deny(int pkey)
+{
+ pkey_disable_set(pkey, PKEY_DISABLE_ACCESS);
+}
+
+/* Failed address bound checks: */
+#ifndef SEGV_BNDERR
+# define SEGV_BNDERR 3
+#endif
+
+#ifndef SEGV_PKUERR
+# define SEGV_PKUERR 4
+#endif
+
+static char *si_code_str(int si_code)
+{
+ if (si_code == SEGV_MAPERR)
+ return "SEGV_MAPERR";
+ if (si_code == SEGV_ACCERR)
+ return "SEGV_ACCERR";
+ if (si_code == SEGV_BNDERR)
+ return "SEGV_BNDERR";
+ if (si_code == SEGV_PKUERR)
+ return "SEGV_PKUERR";
+ return "UNKNOWN";
+}
+
+int pkey_faults;
+int last_si_pkey = -1;
+void signal_handler(int signum, siginfo_t *si, void *vucontext)
+{
+ ucontext_t *uctxt = vucontext;
+ int trapno;
+ unsigned long ip;
+ char *fpregs;
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+ u32 *pkey_reg_ptr;
+ int pkey_reg_offset;
+#endif /* arch */
+ u64 siginfo_pkey;
+ u32 *si_pkey_ptr;
+
+ dprint_in_signal = 1;
+ dprintf1(">>>>===============SIGSEGV============================\n");
+ dprintf1("%s()::%d, pkey_reg: 0x%016llx shadow: %016llx\n",
+ __func__, __LINE__,
+ __read_pkey_reg(), shadow_pkey_reg);
+
+ trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
+ ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
+ fpregs = (char *) uctxt->uc_mcontext.fpregs;
+
+ dprintf2("%s() trapno: %d ip: 0x%016lx info->si_code: %s/%d\n",
+ __func__, trapno, ip, si_code_str(si->si_code),
+ si->si_code);
+
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+#ifdef __i386__
+ /*
+ * 32-bit has some extra padding so that userspace can tell whether
+ * the XSTATE header is present in addition to the "legacy" FPU
+ * state. We just assume that it is here.
+ */
+ fpregs += 0x70;
+#endif /* i386 */
+ pkey_reg_offset = pkey_reg_xstate_offset();
+ pkey_reg_ptr = (void *)(&fpregs[pkey_reg_offset]);
+
+ /*
+ * If we got a PKEY fault, we *HAVE* to have at least one bit set in
+ * here.
+ */
+ dprintf1("pkey_reg_xstate_offset: %d\n", pkey_reg_xstate_offset());
+ if (DEBUG_LEVEL > 4)
+ dump_mem(pkey_reg_ptr - 128, 256);
+ pkey_assert(*pkey_reg_ptr);
+#endif /* arch */
+
+ dprintf1("siginfo: %p\n", si);
+ dprintf1(" fpregs: %p\n", fpregs);
+
+ if ((si->si_code == SEGV_MAPERR) ||
+ (si->si_code == SEGV_ACCERR) ||
+ (si->si_code == SEGV_BNDERR)) {
+ printf("non-PK si_code, exiting...\n");
+ exit(4);
+ }
+
+ si_pkey_ptr = siginfo_get_pkey_ptr(si);
+ dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
+ dump_mem((u8 *)si_pkey_ptr - 8, 24);
+ siginfo_pkey = *si_pkey_ptr;
+ pkey_assert(siginfo_pkey < NR_PKEYS);
+ last_si_pkey = siginfo_pkey;
+
+ /*
+ * need __read_pkey_reg() version so we do not do shadow_pkey_reg
+ * checking
+ */
+ dprintf1("signal pkey_reg from pkey_reg: %016llx\n",
+ __read_pkey_reg());
+ dprintf1("pkey from siginfo: %016llx\n", siginfo_pkey);
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+ dprintf1("signal pkey_reg from xsave: %08x\n", *pkey_reg_ptr);
+ *(u64 *)pkey_reg_ptr = 0x00000000;
+ dprintf1("WARNING: set PKEY_REG=0 to allow faulting instruction to continue\n");
+#elif defined(__powerpc64__) /* arch */
+ /* restore access and let the faulting instruction continue */
+ pkey_access_allow(siginfo_pkey);
+#endif /* arch */
+ pkey_faults++;
+ dprintf1("<<<<==================================================\n");
+ dprint_in_signal = 0;
+}
+
+int wait_all_children(void)
+{
+ int status;
+ return waitpid(-1, &status, 0);
+}
+
+void sig_chld(int x)
+{
+ dprint_in_signal = 1;
+ dprintf2("[%d] SIGCHLD: %d\n", getpid(), x);
+ dprint_in_signal = 0;
+}
+
+void setup_sigsegv_handler(void)
+{
+ int r, rs;
+ struct sigaction newact;
+ struct sigaction oldact;
+
+ /* #PF is mapped to sigsegv */
+ int signum = SIGSEGV;
+
+ newact.sa_handler = 0;
+ newact.sa_sigaction = signal_handler;
+
+ /*sigset_t - signals to block while in the handler */
+ /* get the old signal mask. */
+ rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask);
+ pkey_assert(rs == 0);
+
+ /* call sa_sigaction, not sa_handler*/
+ newact.sa_flags = SA_SIGINFO;
+
+ newact.sa_restorer = 0; /* void(*)(), obsolete */
+ r = sigaction(signum, &newact, &oldact);
+ r = sigaction(SIGALRM, &newact, &oldact);
+ pkey_assert(r == 0);
+}
+
+void setup_handlers(void)
+{
+ signal(SIGCHLD, &sig_chld);
+ setup_sigsegv_handler();
+}
+
+pid_t fork_lazy_child(void)
+{
+ pid_t forkret;
+
+ forkret = fork();
+ pkey_assert(forkret >= 0);
+ dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
+
+ if (!forkret) {
+ /* in the child */
+ while (1) {
+ dprintf1("child sleeping...\n");
+ sleep(30);
+ }
+ }
+ return forkret;
+}
+
+int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
+ unsigned long pkey)
+{
+ int sret;
+
+ dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__,
+ ptr, size, orig_prot, pkey);
+
+ errno = 0;
+ sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey);
+ if (errno) {
+ dprintf2("SYS_mprotect_key sret: %d\n", sret);
+ dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot);
+ dprintf2("SYS_mprotect_key failed, errno: %d\n", errno);
+ if (DEBUG_LEVEL >= 2)
+ perror("SYS_mprotect_pkey");
+ }
+ return sret;
+}
+
+int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
+{
+ int ret = syscall(SYS_pkey_alloc, flags, init_val);
+ dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
+ __func__, flags, init_val, ret, errno);
+ return ret;
+}
+
+int alloc_pkey(void)
+{
+ int ret;
+ unsigned long init_val = 0x0;
+
+ dprintf1("%s()::%d, pkey_reg: 0x%016llx shadow: %016llx\n",
+ __func__, __LINE__, __read_pkey_reg(), shadow_pkey_reg);
+ ret = sys_pkey_alloc(0, init_val);
+ /*
+ * pkey_alloc() sets PKEY register, so we need to reflect it in
+ * shadow_pkey_reg:
+ */
+ dprintf4("%s()::%d, ret: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n",
+ __func__, __LINE__, ret, __read_pkey_reg(),
+ shadow_pkey_reg);
+ if (ret > 0) {
+ /* clear both the bits: */
+ shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, ret,
+ ~PKEY_MASK);
+ dprintf4("%s()::%d, ret: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n",
+ __func__,
+ __LINE__, ret, __read_pkey_reg(),
+ shadow_pkey_reg);
+ /*
+ * move the new state in from init_val
+ * (remember, we cheated and init_val == pkey_reg format)
+ */
+ shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, ret,
+ init_val);
+ }
+ dprintf4("%s()::%d, ret: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n",
+ __func__, __LINE__, ret, __read_pkey_reg(),
+ shadow_pkey_reg);
+ dprintf1("%s()::%d errno: %d\n", __func__, __LINE__, errno);
+ /* for shadow checking: */
+ read_pkey_reg();
+ dprintf4("%s()::%d, ret: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n",
+ __func__, __LINE__, ret, __read_pkey_reg(),
+ shadow_pkey_reg);
+ return ret;
+}
+
+int sys_pkey_free(unsigned long pkey)
+{
+ int ret = syscall(SYS_pkey_free, pkey);
+ dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
+ return ret;
+}
+
+/*
+ * I had a bug where pkey bits could be set by mprotect() but
+ * not cleared. This ensures we get lots of random bit sets
+ * and clears on the vma and pte pkey bits.
+ */
+int alloc_random_pkey(void)
+{
+ int max_nr_pkey_allocs;
+ int ret;
+ int i;
+ int alloced_pkeys[NR_PKEYS];
+ int nr_alloced = 0;
+ int random_index;
+ memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
+
+ /* allocate every possible key and make a note of which ones we got */
+ max_nr_pkey_allocs = NR_PKEYS;
+ for (i = 0; i < max_nr_pkey_allocs; i++) {
+ int new_pkey = alloc_pkey();
+ if (new_pkey < 0)
+ break;
+ alloced_pkeys[nr_alloced++] = new_pkey;
+ }
+
+ pkey_assert(nr_alloced > 0);
+ /* select a random one out of the allocated ones */
+ random_index = rand() % nr_alloced;
+ ret = alloced_pkeys[random_index];
+ /* now zero it out so we don't free it next */
+ alloced_pkeys[random_index] = 0;
+
+ /* go through the allocated ones that we did not want and free them */
+ for (i = 0; i < nr_alloced; i++) {
+ int free_ret;
+ if (!alloced_pkeys[i])
+ continue;
+ free_ret = sys_pkey_free(alloced_pkeys[i]);
+ pkey_assert(!free_ret);
+ }
+ dprintf1("%s()::%d, ret: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n", __func__,
+ __LINE__, ret, __read_pkey_reg(), shadow_pkey_reg);
+ return ret;
+}
+
+int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
+ unsigned long pkey)
+{
+ int nr_iterations = random() % 100;
+ int ret;
+
+ while (0) {
+ int rpkey = alloc_random_pkey();
+ ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
+ dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
+ ptr, size, orig_prot, pkey, ret);
+ if (nr_iterations-- < 0)
+ break;
+
+ dprintf1("%s()::%d, ret: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n",
+ __func__, __LINE__, ret, __read_pkey_reg(),
+ shadow_pkey_reg);
+ sys_pkey_free(rpkey);
+ dprintf1("%s()::%d, ret: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n",
+ __func__, __LINE__, ret, __read_pkey_reg(),
+ shadow_pkey_reg);
+ }
+ pkey_assert(pkey < NR_PKEYS);
+
+ ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
+ dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
+ ptr, size, orig_prot, pkey, ret);
+ pkey_assert(!ret);
+ dprintf1("%s()::%d, ret: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n", __func__,
+ __LINE__, ret, __read_pkey_reg(), shadow_pkey_reg);
+ return ret;
+}
+
+struct pkey_malloc_record {
+ void *ptr;
+ long size;
+ int prot;
+};
+struct pkey_malloc_record *pkey_malloc_records;
+struct pkey_malloc_record *pkey_last_malloc_record;
+long nr_pkey_malloc_records;
+void record_pkey_malloc(void *ptr, long size, int prot)
+{
+ long i;
+ struct pkey_malloc_record *rec = NULL;
+
+ for (i = 0; i < nr_pkey_malloc_records; i++) {
+ rec = &pkey_malloc_records[i];
+ /* find a free record */
+ if (rec)
+ break;
+ }
+ if (!rec) {
+ /* every record is full */
+ size_t old_nr_records = nr_pkey_malloc_records;
+ size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
+ size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
+ dprintf2("new_nr_records: %zd\n", new_nr_records);
+ dprintf2("new_size: %zd\n", new_size);
+ pkey_malloc_records = realloc(pkey_malloc_records, new_size);
+ pkey_assert(pkey_malloc_records != NULL);
+ rec = &pkey_malloc_records[nr_pkey_malloc_records];
+ /*
+ * realloc() does not initialize memory, so zero it from
+ * the first new record all the way to the end.
+ */
+ for (i = 0; i < new_nr_records - old_nr_records; i++)
+ memset(rec + i, 0, sizeof(*rec));
+ }
+ dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n",
+ (int)(rec - pkey_malloc_records), rec, ptr, size);
+ rec->ptr = ptr;
+ rec->size = size;
+ rec->prot = prot;
+ pkey_last_malloc_record = rec;
+ nr_pkey_malloc_records++;
+}
+
+void free_pkey_malloc(void *ptr)
+{
+ long i;
+ int ret;
+ dprintf3("%s(%p)\n", __func__, ptr);
+ for (i = 0; i < nr_pkey_malloc_records; i++) {
+ struct pkey_malloc_record *rec = &pkey_malloc_records[i];
+ dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
+ ptr, i, rec, rec->ptr, rec->size);
+ if ((ptr < rec->ptr) ||
+ (ptr >= rec->ptr + rec->size))
+ continue;
+
+ dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n",
+ ptr, i, rec, rec->ptr, rec->size);
+ nr_pkey_malloc_records--;
+ ret = munmap(rec->ptr, rec->size);
+ dprintf3("munmap ret: %d\n", ret);
+ pkey_assert(!ret);
+ dprintf3("clearing rec->ptr, rec: %p\n", rec);
+ rec->ptr = NULL;
+ dprintf3("done clearing rec->ptr, rec: %p\n", rec);
+ return;
+ }
+ pkey_assert(false);
+}
+
+
+void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
+{
+ void *ptr;
+ int ret;
+
+ read_pkey_reg();
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ pkey_assert(pkey < NR_PKEYS);
+ ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+ ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
+ pkey_assert(!ret);
+ record_pkey_malloc(ptr, size, prot);
+ read_pkey_reg();
+
+ dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
+ return ptr;
+}
+
+void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
+{
+ int ret;
+ void *ptr;
+
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ /*
+ * Guarantee we can fit at least one huge page in the resulting
+ * allocation by allocating space for 2:
+ */
+ size = ALIGN_UP(size, HPAGE_SIZE * 2);
+ ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+ record_pkey_malloc(ptr, size, prot);
+ mprotect_pkey(ptr, size, prot, pkey);
+
+ dprintf1("unaligned ptr: %p\n", ptr);
+ ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE);
+ dprintf1(" aligned ptr: %p\n", ptr);
+ ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE);
+ dprintf1("MADV_HUGEPAGE ret: %d\n", ret);
+ ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED);
+ dprintf1("MADV_WILLNEED ret: %d\n", ret);
+ memset(ptr, 0, HPAGE_SIZE);
+
+ dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr);
+ return ptr;
+}
+
+int hugetlb_setup_ok;
+#define SYSFS_FMT_NR_HUGE_PAGES "/sys/kernel/mm/hugepages/hugepages-%ldkB/nr_hugepages"
+#define GET_NR_HUGE_PAGES 10
+void setup_hugetlbfs(void)
+{
+ int err;
+ int fd;
+ char buf[256];
+ long hpagesz_kb;
+ long hpagesz_mb;
+
+ if (geteuid() != 0) {
+ fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
+ return;
+ }
+
+ cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
+
+ /*
+ * Now go make sure that we got the pages and that they
+ * are PMD-level pages. Someone might have made PUD-level
+ * pages the default.
+ */
+ hpagesz_kb = HPAGE_SIZE / 1024;
+ hpagesz_mb = hpagesz_kb / 1024;
+ sprintf(buf, SYSFS_FMT_NR_HUGE_PAGES, hpagesz_kb);
+ fd = open(buf, O_RDONLY);
+ if (fd < 0) {
+ fprintf(stderr, "opening sysfs %ldM hugetlb config: %s\n",
+ hpagesz_mb, strerror(errno));
+ return;
+ }
+
+ /* -1 to guarantee leaving the trailing \0 */
+ err = read(fd, buf, sizeof(buf)-1);
+ close(fd);
+ if (err <= 0) {
+ fprintf(stderr, "reading sysfs %ldM hugetlb config: %s\n",
+ hpagesz_mb, strerror(errno));
+ return;
+ }
+
+ if (atoi(buf) != GET_NR_HUGE_PAGES) {
+ fprintf(stderr, "could not confirm %ldM pages, got: '%s' expected %d\n",
+ hpagesz_mb, buf, GET_NR_HUGE_PAGES);
+ return;
+ }
+
+ hugetlb_setup_ok = 1;
+}
+
+void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
+{
+ void *ptr;
+ int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB;
+
+ if (!hugetlb_setup_ok)
+ return PTR_ERR_ENOTSUP;
+
+ dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey);
+ size = ALIGN_UP(size, HPAGE_SIZE * 2);
+ pkey_assert(pkey < NR_PKEYS);
+ ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
+ pkey_assert(ptr != (void *)-1);
+ mprotect_pkey(ptr, size, prot, pkey);
+
+ record_pkey_malloc(ptr, size, prot);
+
+ dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
+ return ptr;
+}
+
+void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
+{
+ void *ptr;
+ int fd;
+
+ dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
+ size, prot, pkey);
+ pkey_assert(pkey < NR_PKEYS);
+ fd = open("/dax/foo", O_RDWR);
+ pkey_assert(fd >= 0);
+
+ ptr = mmap(0, size, prot, MAP_SHARED, fd, 0);
+ pkey_assert(ptr != (void *)-1);
+
+ mprotect_pkey(ptr, size, prot, pkey);
+
+ record_pkey_malloc(ptr, size, prot);
+
+ dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
+ close(fd);
+ return ptr;
+}
+
+void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
+
+ malloc_pkey_with_mprotect,
+ malloc_pkey_with_mprotect_subpage,
+ malloc_pkey_anon_huge,
+ malloc_pkey_hugetlb
+/* can not do direct with the pkey_mprotect() API:
+ malloc_pkey_mmap_direct,
+ malloc_pkey_mmap_dax,
+*/
+};
+
+void *malloc_pkey(long size, int prot, u16 pkey)
+{
+ void *ret;
+ static int malloc_type;
+ int nr_malloc_types = ARRAY_SIZE(pkey_malloc);
+
+ pkey_assert(pkey < NR_PKEYS);
+
+ while (1) {
+ pkey_assert(malloc_type < nr_malloc_types);
+
+ ret = pkey_malloc[malloc_type](size, prot, pkey);
+ pkey_assert(ret != (void *)-1);
+
+ malloc_type++;
+ if (malloc_type >= nr_malloc_types)
+ malloc_type = (random()%nr_malloc_types);
+
+ /* try again if the malloc_type we tried is unsupported */
+ if (ret == PTR_ERR_ENOTSUP)
+ continue;
+
+ break;
+ }
+
+ dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__,
+ size, prot, pkey, ret);
+ return ret;
+}
+
+int last_pkey_faults;
+#define UNKNOWN_PKEY -2
+void expected_pkey_fault(int pkey)
+{
+ dprintf2("%s(): last_pkey_faults: %d pkey_faults: %d\n",
+ __func__, last_pkey_faults, pkey_faults);
+ dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
+ pkey_assert(last_pkey_faults + 1 == pkey_faults);
+
+ /*
+ * For exec-only memory, we do not know the pkey in
+ * advance, so skip this check.
+ */
+ if (pkey != UNKNOWN_PKEY)
+ pkey_assert(last_si_pkey == pkey);
+
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+ /*
+ * The signal handler shold have cleared out PKEY register to let the
+ * test program continue. We now have to restore it.
+ */
+ if (__read_pkey_reg() != 0)
+#else /* arch */
+ if (__read_pkey_reg() != shadow_pkey_reg)
+#endif /* arch */
+ pkey_assert(0);
+
+ __write_pkey_reg(shadow_pkey_reg);
+ dprintf1("%s() set pkey_reg=%016llx to restore state after signal "
+ "nuked it\n", __func__, shadow_pkey_reg);
+ last_pkey_faults = pkey_faults;
+ last_si_pkey = -1;
+}
+
+#define do_not_expect_pkey_fault(msg) do { \
+ if (last_pkey_faults != pkey_faults) \
+ dprintf0("unexpected PKey fault: %s\n", msg); \
+ pkey_assert(last_pkey_faults == pkey_faults); \
+} while (0)
+
+int test_fds[10] = { -1 };
+int nr_test_fds;
+void __save_test_fd(int fd)
+{
+ pkey_assert(fd >= 0);
+ pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds));
+ test_fds[nr_test_fds] = fd;
+ nr_test_fds++;
+}
+
+int get_test_read_fd(void)
+{
+ int test_fd = open("/etc/passwd", O_RDONLY);
+ __save_test_fd(test_fd);
+ return test_fd;
+}
+
+void close_test_fds(void)
+{
+ int i;
+
+ for (i = 0; i < nr_test_fds; i++) {
+ if (test_fds[i] < 0)
+ continue;
+ close(test_fds[i]);
+ test_fds[i] = -1;
+ }
+ nr_test_fds = 0;
+}
+
+#define barrier() __asm__ __volatile__("": : :"memory")
+__attribute__((noinline)) int read_ptr(int *ptr)
+{
+ /*
+ * Keep GCC from optimizing this away somehow
+ */
+ barrier();
+ return *ptr;
+}
+
+void test_pkey_alloc_free_attach_pkey0(int *ptr, u16 pkey)
+{
+ int i, err;
+ int max_nr_pkey_allocs;
+ int alloced_pkeys[NR_PKEYS];
+ int nr_alloced = 0;
+ long size;
+
+ pkey_assert(pkey_last_malloc_record);
+ size = pkey_last_malloc_record->size;
+ /*
+ * This is a bit of a hack. But mprotect() requires
+ * huge-page-aligned sizes when operating on hugetlbfs.
+ * So, make sure that we use something that's a multiple
+ * of a huge page when we can.
+ */
+ if (size >= HPAGE_SIZE)
+ size = HPAGE_SIZE;
+
+ /* allocate every possible key and make sure key-0 never got allocated */
+ max_nr_pkey_allocs = NR_PKEYS;
+ for (i = 0; i < max_nr_pkey_allocs; i++) {
+ int new_pkey = alloc_pkey();
+ pkey_assert(new_pkey != 0);
+
+ if (new_pkey < 0)
+ break;
+ alloced_pkeys[nr_alloced++] = new_pkey;
+ }
+ /* free all the allocated keys */
+ for (i = 0; i < nr_alloced; i++) {
+ int free_ret;
+
+ if (!alloced_pkeys[i])
+ continue;
+ free_ret = sys_pkey_free(alloced_pkeys[i]);
+ pkey_assert(!free_ret);
+ }
+
+ /* attach key-0 in various modes */
+ err = sys_mprotect_pkey(ptr, size, PROT_READ, 0);
+ pkey_assert(!err);
+ err = sys_mprotect_pkey(ptr, size, PROT_WRITE, 0);
+ pkey_assert(!err);
+ err = sys_mprotect_pkey(ptr, size, PROT_EXEC, 0);
+ pkey_assert(!err);
+ err = sys_mprotect_pkey(ptr, size, PROT_READ|PROT_WRITE, 0);
+ pkey_assert(!err);
+ err = sys_mprotect_pkey(ptr, size, PROT_READ|PROT_WRITE|PROT_EXEC, 0);
+ pkey_assert(!err);
+}
+
+void test_read_of_write_disabled_region(int *ptr, u16 pkey)
+{
+ int ptr_contents;
+
+ dprintf1("disabling write access to PKEY[1], doing read\n");
+ pkey_write_deny(pkey);
+ ptr_contents = read_ptr(ptr);
+ dprintf1("*ptr: %d\n", ptr_contents);
+ dprintf1("\n");
+}
+void test_read_of_access_disabled_region(int *ptr, u16 pkey)
+{
+ int ptr_contents;
+
+ dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
+ read_pkey_reg();
+ pkey_access_deny(pkey);
+ ptr_contents = read_ptr(ptr);
+ dprintf1("*ptr: %d\n", ptr_contents);
+ expected_pkey_fault(pkey);
+}
+
+void test_read_of_access_disabled_region_with_page_already_mapped(int *ptr,
+ u16 pkey)
+{
+ int ptr_contents;
+
+ dprintf1("disabling access to PKEY[%02d], doing read @ %p\n",
+ pkey, ptr);
+ ptr_contents = read_ptr(ptr);
+ dprintf1("reading ptr before disabling the read : %d\n",
+ ptr_contents);
+ read_pkey_reg();
+ pkey_access_deny(pkey);
+ ptr_contents = read_ptr(ptr);
+ dprintf1("*ptr: %d\n", ptr_contents);
+ expected_pkey_fault(pkey);
+}
+
+void test_write_of_write_disabled_region_with_page_already_mapped(int *ptr,
+ u16 pkey)
+{
+ *ptr = __LINE__;
+ dprintf1("disabling write access; after accessing the page, "
+ "to PKEY[%02d], doing write\n", pkey);
+ pkey_write_deny(pkey);
+ *ptr = __LINE__;
+ expected_pkey_fault(pkey);
+}
+
+void test_write_of_write_disabled_region(int *ptr, u16 pkey)
+{
+ dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
+ pkey_write_deny(pkey);
+ *ptr = __LINE__;
+ expected_pkey_fault(pkey);
+}
+void test_write_of_access_disabled_region(int *ptr, u16 pkey)
+{
+ dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
+ pkey_access_deny(pkey);
+ *ptr = __LINE__;
+ expected_pkey_fault(pkey);
+}
+
+void test_write_of_access_disabled_region_with_page_already_mapped(int *ptr,
+ u16 pkey)
+{
+ *ptr = __LINE__;
+ dprintf1("disabling access; after accessing the page, "
+ " to PKEY[%02d], doing write\n", pkey);
+ pkey_access_deny(pkey);
+ *ptr = __LINE__;
+ expected_pkey_fault(pkey);
+}
+
+void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
+{
+ int ret;
+ int test_fd = get_test_read_fd();
+
+ dprintf1("disabling access to PKEY[%02d], "
+ "having kernel read() to buffer\n", pkey);
+ pkey_access_deny(pkey);
+ ret = read(test_fd, ptr, 1);
+ dprintf1("read ret: %d\n", ret);
+ pkey_assert(ret);
+}
+void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey)
+{
+ int ret;
+ int test_fd = get_test_read_fd();
+
+ pkey_write_deny(pkey);
+ ret = read(test_fd, ptr, 100);
+ dprintf1("read ret: %d\n", ret);
+ if (ret < 0 && (DEBUG_LEVEL > 0))
+ perror("verbose read result (OK for this to be bad)");
+ pkey_assert(ret);
+}
+
+void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey)
+{
+ int pipe_ret, vmsplice_ret;
+ struct iovec iov;
+ int pipe_fds[2];
+
+ pipe_ret = pipe(pipe_fds);
+
+ pkey_assert(pipe_ret == 0);
+ dprintf1("disabling access to PKEY[%02d], "
+ "having kernel vmsplice from buffer\n", pkey);
+ pkey_access_deny(pkey);
+ iov.iov_base = ptr;
+ iov.iov_len = PAGE_SIZE;
+ vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT);
+ dprintf1("vmsplice() ret: %d\n", vmsplice_ret);
+ pkey_assert(vmsplice_ret == -1);
+
+ close(pipe_fds[0]);
+ close(pipe_fds[1]);
+}
+
+void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
+{
+ int ignored = 0xdada;
+ int futex_ret;
+ int some_int = __LINE__;
+
+ dprintf1("disabling write to PKEY[%02d], "
+ "doing futex gunk in buffer\n", pkey);
+ *ptr = some_int;
+ pkey_write_deny(pkey);
+ futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL,
+ &ignored, ignored);
+ if (DEBUG_LEVEL > 0)
+ perror("futex");
+ dprintf1("futex() ret: %d\n", futex_ret);
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
+{
+ int err;
+ int i;
+
+ /* Note: 0 is the default pkey, so don't mess with it */
+ for (i = 1; i < NR_PKEYS; i++) {
+ if (pkey == i)
+ continue;
+
+ dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i);
+ err = sys_pkey_free(i);
+ pkey_assert(err);
+
+ err = sys_pkey_free(i);
+ pkey_assert(err);
+
+ err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i);
+ pkey_assert(err);
+ }
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
+{
+ int err;
+ int bad_pkey = NR_PKEYS+99;
+
+ /* pass a known-invalid pkey in: */
+ err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
+ pkey_assert(err);
+}
+
+void become_child(void)
+{
+ pid_t forkret;
+
+ forkret = fork();
+ pkey_assert(forkret >= 0);
+ dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
+
+ if (!forkret) {
+ /* in the child */
+ return;
+ }
+ exit(0);
+}
+
+/* Assumes that all pkeys other than 'pkey' are unallocated */
+void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
+{
+ int err;
+ int allocated_pkeys[NR_PKEYS] = {0};
+ int nr_allocated_pkeys = 0;
+ int i;
+
+ for (i = 0; i < NR_PKEYS*3; i++) {
+ int new_pkey;
+ dprintf1("%s() alloc loop: %d\n", __func__, i);
+ new_pkey = alloc_pkey();
+ dprintf4("%s()::%d, err: %d pkey_reg: 0x%016llx"
+ " shadow: 0x%016llx\n",
+ __func__, __LINE__, err, __read_pkey_reg(),
+ shadow_pkey_reg);
+ read_pkey_reg(); /* for shadow checking */
+ dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
+ if ((new_pkey == -1) && (errno == ENOSPC)) {
+ dprintf2("%s() failed to allocate pkey after %d tries\n",
+ __func__, nr_allocated_pkeys);
+ } else {
+ /*
+ * Ensure the number of successes never
+ * exceeds the number of keys supported
+ * in the hardware.
+ */
+ pkey_assert(nr_allocated_pkeys < NR_PKEYS);
+ allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
+ }
+
+ /*
+ * Make sure that allocation state is properly
+ * preserved across fork().
+ */
+ if (i == NR_PKEYS*2)
+ become_child();
+ }
+
+ dprintf3("%s()::%d\n", __func__, __LINE__);
+
+ /*
+ * On x86:
+ * There are 16 pkeys supported in hardware. Three are
+ * allocated by the time we get here:
+ * 1. The default key (0)
+ * 2. One possibly consumed by an execute-only mapping.
+ * 3. One allocated by the test code and passed in via
+ * 'pkey' to this function.
+ * Ensure that we can allocate at least another 13 (16-3).
+ *
+ * On powerpc:
+ * There are either 5, 28, 29 or 32 pkeys supported in
+ * hardware depending on the page size (4K or 64K) and
+ * platform (powernv or powervm). Four are allocated by
+ * the time we get here. These include pkey-0, pkey-1,
+ * exec-only pkey and the one allocated by the test code.
+ * Ensure that we can allocate the remaining.
+ */
+ pkey_assert(i >= (NR_PKEYS - get_arch_reserved_keys() - 1));
+
+ for (i = 0; i < nr_allocated_pkeys; i++) {
+ err = sys_pkey_free(allocated_pkeys[i]);
+ pkey_assert(!err);
+ read_pkey_reg(); /* for shadow checking */
+ }
+}
+
+void arch_force_pkey_reg_init(void)
+{
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+ u64 *buf;
+
+ /*
+ * All keys should be allocated and set to allow reads and
+ * writes, so the register should be all 0. If not, just
+ * skip the test.
+ */
+ if (read_pkey_reg())
+ return;
+
+ /*
+ * Just allocate an absurd about of memory rather than
+ * doing the XSAVE size enumeration dance.
+ */
+ buf = mmap(NULL, 1*MB, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+
+ /* These __builtins require compiling with -mxsave */
+
+ /* XSAVE to build a valid buffer: */
+ __builtin_ia32_xsave(buf, XSTATE_PKEY);
+ /* Clear XSTATE_BV[PKRU]: */
+ buf[XSTATE_BV_OFFSET/sizeof(u64)] &= ~XSTATE_PKEY;
+ /* XRSTOR will likely get PKRU back to the init state: */
+ __builtin_ia32_xrstor(buf, XSTATE_PKEY);
+
+ munmap(buf, 1*MB);
+#endif
+}
+
+
+/*
+ * This is mostly useless on ppc for now. But it will not
+ * hurt anything and should give some better coverage as
+ * a long-running test that continually checks the pkey
+ * register.
+ */
+void test_pkey_init_state(int *ptr, u16 pkey)
+{
+ int err;
+ int allocated_pkeys[NR_PKEYS] = {0};
+ int nr_allocated_pkeys = 0;
+ int i;
+
+ for (i = 0; i < NR_PKEYS; i++) {
+ int new_pkey = alloc_pkey();
+
+ if (new_pkey < 0)
+ continue;
+ allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
+ }
+
+ dprintf3("%s()::%d\n", __func__, __LINE__);
+
+ arch_force_pkey_reg_init();
+
+ /*
+ * Loop for a bit, hoping to get exercise the kernel
+ * context switch code.
+ */
+ for (i = 0; i < 1000000; i++)
+ read_pkey_reg();
+
+ for (i = 0; i < nr_allocated_pkeys; i++) {
+ err = sys_pkey_free(allocated_pkeys[i]);
+ pkey_assert(!err);
+ read_pkey_reg(); /* for shadow checking */
+ }
+}
+
+/*
+ * pkey 0 is special. It is allocated by default, so you do not
+ * have to call pkey_alloc() to use it first. Make sure that it
+ * is usable.
+ */
+void test_mprotect_with_pkey_0(int *ptr, u16 pkey)
+{
+ long size;
+ int prot;
+
+ assert(pkey_last_malloc_record);
+ size = pkey_last_malloc_record->size;
+ /*
+ * This is a bit of a hack. But mprotect() requires
+ * huge-page-aligned sizes when operating on hugetlbfs.
+ * So, make sure that we use something that's a multiple
+ * of a huge page when we can.
+ */
+ if (size >= HPAGE_SIZE)
+ size = HPAGE_SIZE;
+ prot = pkey_last_malloc_record->prot;
+
+ /* Use pkey 0 */
+ mprotect_pkey(ptr, size, prot, 0);
+
+ /* Make sure that we can set it back to the original pkey. */
+ mprotect_pkey(ptr, size, prot, pkey);
+}
+
+void test_ptrace_of_child(int *ptr, u16 pkey)
+{
+ __attribute__((__unused__)) int peek_result;
+ pid_t child_pid;
+ void *ignored = 0;
+ long ret;
+ int status;
+ /*
+ * This is the "control" for our little expermient. Make sure
+ * we can always access it when ptracing.
+ */
+ int *plain_ptr_unaligned = malloc(HPAGE_SIZE);
+ int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE);
+
+ /*
+ * Fork a child which is an exact copy of this process, of course.
+ * That means we can do all of our tests via ptrace() and then plain
+ * memory access and ensure they work differently.
+ */
+ child_pid = fork_lazy_child();
+ dprintf1("[%d] child pid: %d\n", getpid(), child_pid);
+
+ ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored);
+ if (ret)
+ perror("attach");
+ dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__);
+ pkey_assert(ret != -1);
+ ret = waitpid(child_pid, &status, WUNTRACED);
+ if ((ret != child_pid) || !(WIFSTOPPED(status))) {
+ fprintf(stderr, "weird waitpid result %ld stat %x\n",
+ ret, status);
+ pkey_assert(0);
+ }
+ dprintf2("waitpid ret: %ld\n", ret);
+ dprintf2("waitpid status: %d\n", status);
+
+ pkey_access_deny(pkey);
+ pkey_write_deny(pkey);
+
+ /* Write access, untested for now:
+ ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
+ pkey_assert(ret != -1);
+ dprintf1("poke at %p: %ld\n", peek_at, ret);
+ */
+
+ /*
+ * Try to access the pkey-protected "ptr" via ptrace:
+ */
+ ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored);
+ /* expect it to work, without an error: */
+ pkey_assert(ret != -1);
+ /* Now access from the current task, and expect an exception: */
+ peek_result = read_ptr(ptr);
+ expected_pkey_fault(pkey);
+
+ /*
+ * Try to access the NON-pkey-protected "plain_ptr" via ptrace:
+ */
+ ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored);
+ /* expect it to work, without an error: */
+ pkey_assert(ret != -1);
+ /* Now access from the current task, and expect NO exception: */
+ peek_result = read_ptr(plain_ptr);
+ do_not_expect_pkey_fault("read plain pointer after ptrace");
+
+ ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
+ pkey_assert(ret != -1);
+
+ ret = kill(child_pid, SIGKILL);
+ pkey_assert(ret != -1);
+
+ wait(&status);
+
+ free(plain_ptr_unaligned);
+}
+
+void *get_pointer_to_instructions(void)
+{
+ void *p1;
+
+ p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE);
+ dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write);
+ /* lots_o_noops_around_write should be page-aligned already */
+ assert(p1 == &lots_o_noops_around_write);
+
+ /* Point 'p1' at the *second* page of the function: */
+ p1 += PAGE_SIZE;
+
+ /*
+ * Try to ensure we fault this in on next touch to ensure
+ * we get an instruction fault as opposed to a data one
+ */
+ madvise(p1, PAGE_SIZE, MADV_DONTNEED);
+
+ return p1;
+}
+
+void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
+{
+ void *p1;
+ int scratch;
+ int ptr_contents;
+ int ret;
+
+ p1 = get_pointer_to_instructions();
+ lots_o_noops_around_write(&scratch);
+ ptr_contents = read_ptr(p1);
+ dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
+
+ ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey);
+ pkey_assert(!ret);
+ pkey_access_deny(pkey);
+
+ dprintf2("pkey_reg: %016llx\n", read_pkey_reg());
+
+ /*
+ * Make sure this is an *instruction* fault
+ */
+ madvise(p1, PAGE_SIZE, MADV_DONTNEED);
+ lots_o_noops_around_write(&scratch);
+ do_not_expect_pkey_fault("executing on PROT_EXEC memory");
+ expect_fault_on_read_execonly_key(p1, pkey);
+}
+
+void test_implicit_mprotect_exec_only_memory(int *ptr, u16 pkey)
+{
+ void *p1;
+ int scratch;
+ int ptr_contents;
+ int ret;
+
+ dprintf1("%s() start\n", __func__);
+
+ p1 = get_pointer_to_instructions();
+ lots_o_noops_around_write(&scratch);
+ ptr_contents = read_ptr(p1);
+ dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
+
+ /* Use a *normal* mprotect(), not mprotect_pkey(): */
+ ret = mprotect(p1, PAGE_SIZE, PROT_EXEC);
+ pkey_assert(!ret);
+
+ /*
+ * Reset the shadow, assuming that the above mprotect()
+ * correctly changed PKRU, but to an unknown value since
+ * the actual allocated pkey is unknown.
+ */
+ shadow_pkey_reg = __read_pkey_reg();
+
+ dprintf2("pkey_reg: %016llx\n", read_pkey_reg());
+
+ /* Make sure this is an *instruction* fault */
+ madvise(p1, PAGE_SIZE, MADV_DONTNEED);
+ lots_o_noops_around_write(&scratch);
+ do_not_expect_pkey_fault("executing on PROT_EXEC memory");
+ expect_fault_on_read_execonly_key(p1, UNKNOWN_PKEY);
+
+ /*
+ * Put the memory back to non-PROT_EXEC. Should clear the
+ * exec-only pkey off the VMA and allow it to be readable
+ * again. Go to PROT_NONE first to check for a kernel bug
+ * that did not clear the pkey when doing PROT_NONE.
+ */
+ ret = mprotect(p1, PAGE_SIZE, PROT_NONE);
+ pkey_assert(!ret);
+
+ ret = mprotect(p1, PAGE_SIZE, PROT_READ|PROT_EXEC);
+ pkey_assert(!ret);
+ ptr_contents = read_ptr(p1);
+ do_not_expect_pkey_fault("plain read on recently PROT_EXEC area");
+}
+
+#if defined(__i386__) || defined(__x86_64__)
+void test_ptrace_modifies_pkru(int *ptr, u16 pkey)
+{
+ u32 new_pkru;
+ pid_t child;
+ int status, ret;
+ int pkey_offset = pkey_reg_xstate_offset();
+ size_t xsave_size = cpu_max_xsave_size();
+ void *xsave;
+ u32 *pkey_register;
+ u64 *xstate_bv;
+ struct iovec iov;
+
+ new_pkru = ~read_pkey_reg();
+ /* Don't make PROT_EXEC mappings inaccessible */
+ new_pkru &= ~3;
+
+ child = fork();
+ pkey_assert(child >= 0);
+ dprintf3("[%d] fork() ret: %d\n", getpid(), child);
+ if (!child) {
+ ptrace(PTRACE_TRACEME, 0, 0, 0);
+ /* Stop and allow the tracer to modify PKRU directly */
+ raise(SIGSTOP);
+
+ /*
+ * need __read_pkey_reg() version so we do not do shadow_pkey_reg
+ * checking
+ */
+ if (__read_pkey_reg() != new_pkru)
+ exit(1);
+
+ /* Stop and allow the tracer to clear XSTATE_BV for PKRU */
+ raise(SIGSTOP);
+
+ if (__read_pkey_reg() != 0)
+ exit(1);
+
+ /* Stop and allow the tracer to examine PKRU */
+ raise(SIGSTOP);
+
+ exit(0);
+ }
+
+ pkey_assert(child == waitpid(child, &status, 0));
+ dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
+ pkey_assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP);
+
+ xsave = (void *)malloc(xsave_size);
+ pkey_assert(xsave > 0);
+
+ /* Modify the PKRU register directly */
+ iov.iov_base = xsave;
+ iov.iov_len = xsave_size;
+ ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
+ pkey_assert(ret == 0);
+
+ pkey_register = (u32 *)(xsave + pkey_offset);
+ pkey_assert(*pkey_register == read_pkey_reg());
+
+ *pkey_register = new_pkru;
+
+ ret = ptrace(PTRACE_SETREGSET, child, (void *)NT_X86_XSTATE, &iov);
+ pkey_assert(ret == 0);
+
+ /* Test that the modification is visible in ptrace before any execution */
+ memset(xsave, 0xCC, xsave_size);
+ ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
+ pkey_assert(ret == 0);
+ pkey_assert(*pkey_register == new_pkru);
+
+ /* Execute the tracee */
+ ret = ptrace(PTRACE_CONT, child, 0, 0);
+ pkey_assert(ret == 0);
+
+ /* Test that the tracee saw the PKRU value change */
+ pkey_assert(child == waitpid(child, &status, 0));
+ dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
+ pkey_assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP);
+
+ /* Test that the modification is visible in ptrace after execution */
+ memset(xsave, 0xCC, xsave_size);
+ ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
+ pkey_assert(ret == 0);
+ pkey_assert(*pkey_register == new_pkru);
+
+ /* Clear the PKRU bit from XSTATE_BV */
+ xstate_bv = (u64 *)(xsave + 512);
+ *xstate_bv &= ~(1 << 9);
+
+ ret = ptrace(PTRACE_SETREGSET, child, (void *)NT_X86_XSTATE, &iov);
+ pkey_assert(ret == 0);
+
+ /* Test that the modification is visible in ptrace before any execution */
+ memset(xsave, 0xCC, xsave_size);
+ ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
+ pkey_assert(ret == 0);
+ pkey_assert(*pkey_register == 0);
+
+ ret = ptrace(PTRACE_CONT, child, 0, 0);
+ pkey_assert(ret == 0);
+
+ /* Test that the tracee saw the PKRU value go to 0 */
+ pkey_assert(child == waitpid(child, &status, 0));
+ dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
+ pkey_assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP);
+
+ /* Test that the modification is visible in ptrace after execution */
+ memset(xsave, 0xCC, xsave_size);
+ ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
+ pkey_assert(ret == 0);
+ pkey_assert(*pkey_register == 0);
+
+ ret = ptrace(PTRACE_CONT, child, 0, 0);
+ pkey_assert(ret == 0);
+ pkey_assert(child == waitpid(child, &status, 0));
+ dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
+ pkey_assert(WIFEXITED(status));
+ pkey_assert(WEXITSTATUS(status) == 0);
+ free(xsave);
+}
+#endif
+
+void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
+{
+ int size = PAGE_SIZE;
+ int sret;
+
+ if (cpu_has_pkeys()) {
+ dprintf1("SKIP: %s: no CPU support\n", __func__);
+ return;
+ }
+
+ sret = syscall(SYS_mprotect_key, ptr, size, PROT_READ, pkey);
+ pkey_assert(sret < 0);
+}
+
+void (*pkey_tests[])(int *ptr, u16 pkey) = {
+ test_read_of_write_disabled_region,
+ test_read_of_access_disabled_region,
+ test_read_of_access_disabled_region_with_page_already_mapped,
+ test_write_of_write_disabled_region,
+ test_write_of_write_disabled_region_with_page_already_mapped,
+ test_write_of_access_disabled_region,
+ test_write_of_access_disabled_region_with_page_already_mapped,
+ test_kernel_write_of_access_disabled_region,
+ test_kernel_write_of_write_disabled_region,
+ test_kernel_gup_of_access_disabled_region,
+ test_kernel_gup_write_to_write_disabled_region,
+ test_executing_on_unreadable_memory,
+ test_implicit_mprotect_exec_only_memory,
+ test_mprotect_with_pkey_0,
+ test_ptrace_of_child,
+ test_pkey_init_state,
+ test_pkey_syscalls_on_non_allocated_pkey,
+ test_pkey_syscalls_bad_args,
+ test_pkey_alloc_exhaust,
+ test_pkey_alloc_free_attach_pkey0,
+#if defined(__i386__) || defined(__x86_64__)
+ test_ptrace_modifies_pkru,
+#endif
+};
+
+void run_tests_once(void)
+{
+ int *ptr;
+ int prot = PROT_READ|PROT_WRITE;
+
+ for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
+ int pkey;
+ int orig_pkey_faults = pkey_faults;
+
+ dprintf1("======================\n");
+ dprintf1("test %d preparing...\n", test_nr);
+
+ tracing_on();
+ pkey = alloc_random_pkey();
+ dprintf1("test %d starting with pkey: %d\n", test_nr, pkey);
+ ptr = malloc_pkey(PAGE_SIZE, prot, pkey);
+ dprintf1("test %d starting...\n", test_nr);
+ pkey_tests[test_nr](ptr, pkey);
+ dprintf1("freeing test memory: %p\n", ptr);
+ free_pkey_malloc(ptr);
+ sys_pkey_free(pkey);
+
+ dprintf1("pkey_faults: %d\n", pkey_faults);
+ dprintf1("orig_pkey_faults: %d\n", orig_pkey_faults);
+
+ tracing_off();
+ close_test_fds();
+
+ printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
+ dprintf1("======================\n\n");
+ }
+ iteration_nr++;
+}
+
+void pkey_setup_shadow(void)
+{
+ shadow_pkey_reg = __read_pkey_reg();
+}
+
+int main(void)
+{
+ int nr_iterations = 22;
+ int pkeys_supported = is_pkeys_supported();
+
+ srand((unsigned int)time(NULL));
+
+ setup_handlers();
+
+ printf("has pkeys: %d\n", pkeys_supported);
+
+ if (!pkeys_supported) {
+ int size = PAGE_SIZE;
+ int *ptr;
+
+ printf("running PKEY tests for unsupported CPU/OS\n");
+
+ ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ assert(ptr != (void *)-1);
+ test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
+ exit(0);
+ }
+
+ pkey_setup_shadow();
+ printf("startup pkey_reg: %016llx\n", read_pkey_reg());
+ setup_hugetlbfs();
+
+ while (nr_iterations-- > 0)
+ run_tests_once();
+
+ printf("done (all tests OK)\n");
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh
new file mode 100644
index 000000000000..8984e0bb58c7
--- /dev/null
+++ b/tools/testing/selftests/mm/run_vmtests.sh
@@ -0,0 +1,274 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Please run as root
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+exitcode=0
+
+usage() {
+ cat <<EOF
+usage: ${BASH_SOURCE[0]:-$0} [ -h | -t "<categories>"]
+ -t: specify specific categories to tests to run
+ -h: display this message
+
+The default behavior is to run all tests.
+
+Alternatively, specific groups tests can be run by passing a string
+to the -t argument containing one or more of the following categories
+separated by spaces:
+- mmap
+ tests for mmap(2)
+- gup_test
+ tests for gup using gup_test interface
+- userfaultfd
+ tests for userfaultfd(2)
+- compaction
+ a test for the patch "Allow compaction of unevictable pages"
+- mlock
+ tests for mlock(2)
+- mremap
+ tests for mremap(2)
+- hugevm
+ tests for very large virtual address space
+- vmalloc
+ vmalloc smoke tests
+- hmm
+ hmm smoke tests
+- madv_populate
+ test memadvise(2) MADV_POPULATE_{READ,WRITE} options
+- memfd_secret
+ test memfd_secret(2)
+- process_mrelease
+ test process_mrelease(2)
+- ksm
+ ksm tests that do not require >=2 NUMA nodes
+- ksm_numa
+ ksm tests that require >=2 NUMA nodes
+- pkey
+ memory protection key tests
+- soft_dirty
+ test soft dirty page bit semantics
+- cow
+ test copy-on-write semantics
+example: ./run_vmtests.sh -t "hmm mmap ksm"
+EOF
+ exit 0
+}
+
+
+while getopts "ht:" OPT; do
+ case ${OPT} in
+ "h") usage ;;
+ "t") VM_SELFTEST_ITEMS=${OPTARG} ;;
+ esac
+done
+shift $((OPTIND -1))
+
+# default behavior: run all tests
+VM_SELFTEST_ITEMS=${VM_SELFTEST_ITEMS:-default}
+
+test_selected() {
+ if [ "$VM_SELFTEST_ITEMS" == "default" ]; then
+ # If no VM_SELFTEST_ITEMS are specified, run all tests
+ return 0
+ fi
+ # If test selected argument is one of the test items
+ if [[ " ${VM_SELFTEST_ITEMS[*]} " =~ " ${1} " ]]; then
+ return 0
+ else
+ return 1
+ fi
+}
+
+# get huge pagesize and freepages from /proc/meminfo
+while read -r name size unit; do
+ if [ "$name" = "HugePages_Free:" ]; then
+ freepgs="$size"
+ fi
+ if [ "$name" = "Hugepagesize:" ]; then
+ hpgsize_KB="$size"
+ fi
+done < /proc/meminfo
+
+# Simple hugetlbfs tests have a hardcoded minimum requirement of
+# huge pages totaling 256MB (262144KB) in size. The userfaultfd
+# hugetlb test requires a minimum of 2 * nr_cpus huge pages. Take
+# both of these requirements into account and attempt to increase
+# number of huge pages available.
+nr_cpus=$(nproc)
+hpgsize_MB=$((hpgsize_KB / 1024))
+half_ufd_size_MB=$((((nr_cpus * hpgsize_MB + 127) / 128) * 128))
+needmem_KB=$((half_ufd_size_MB * 2 * 1024))
+
+# set proper nr_hugepages
+if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then
+ nr_hugepgs=$(cat /proc/sys/vm/nr_hugepages)
+ needpgs=$((needmem_KB / hpgsize_KB))
+ tries=2
+ while [ "$tries" -gt 0 ] && [ "$freepgs" -lt "$needpgs" ]; do
+ lackpgs=$((needpgs - freepgs))
+ echo 3 > /proc/sys/vm/drop_caches
+ if ! echo $((lackpgs + nr_hugepgs)) > /proc/sys/vm/nr_hugepages; then
+ echo "Please run this test as root"
+ exit $ksft_skip
+ fi
+ while read -r name size unit; do
+ if [ "$name" = "HugePages_Free:" ]; then
+ freepgs=$size
+ fi
+ done < /proc/meminfo
+ tries=$((tries - 1))
+ done
+ if [ "$freepgs" -lt "$needpgs" ]; then
+ printf "Not enough huge pages available (%d < %d)\n" \
+ "$freepgs" "$needpgs"
+ exit 1
+ fi
+else
+ echo "no hugetlbfs support in kernel?"
+ exit 1
+fi
+
+# filter 64bit architectures
+ARCH64STR="arm64 ia64 mips64 parisc64 ppc64 ppc64le riscv64 s390x sh64 sparc64 x86_64"
+if [ -z "$ARCH" ]; then
+ ARCH=$(uname -m 2>/dev/null | sed -e 's/aarch64.*/arm64/')
+fi
+VADDR64=0
+echo "$ARCH64STR" | grep "$ARCH" &>/dev/null && VADDR64=1
+
+# Usage: run_test [test binary] [arbitrary test arguments...]
+run_test() {
+ if test_selected ${CATEGORY}; then
+ local title="running $*"
+ local sep=$(echo -n "$title" | tr "[:graph:][:space:]" -)
+ printf "%s\n%s\n%s\n" "$sep" "$title" "$sep"
+
+ "$@"
+ local ret=$?
+ if [ $ret -eq 0 ]; then
+ echo "[PASS]"
+ elif [ $ret -eq $ksft_skip ]; then
+ echo "[SKIP]"
+ exitcode=$ksft_skip
+ else
+ echo "[FAIL]"
+ exitcode=1
+ fi
+ fi # test_selected
+}
+
+CATEGORY="hugetlb" run_test ./hugepage-mmap
+
+shmmax=$(cat /proc/sys/kernel/shmmax)
+shmall=$(cat /proc/sys/kernel/shmall)
+echo 268435456 > /proc/sys/kernel/shmmax
+echo 4194304 > /proc/sys/kernel/shmall
+CATEGORY="hugetlb" run_test ./hugepage-shm
+echo "$shmmax" > /proc/sys/kernel/shmmax
+echo "$shmall" > /proc/sys/kernel/shmall
+
+CATEGORY="hugetlb" run_test ./map_hugetlb
+CATEGORY="hugetlb" run_test ./hugepage-mremap
+CATEGORY="hugetlb" run_test ./hugepage-vmemmap
+CATEGORY="hugetlb" run_test ./hugetlb-madvise
+
+if test_selected "hugetlb"; then
+ echo "NOTE: These hugetlb tests provide minimal coverage. Use"
+ echo " https://github.com/libhugetlbfs/libhugetlbfs.git for"
+ echo " hugetlb regression testing."
+fi
+
+CATEGORY="mmap" run_test ./map_fixed_noreplace
+
+# get_user_pages_fast() benchmark
+CATEGORY="gup_test" run_test ./gup_test -u
+# pin_user_pages_fast() benchmark
+CATEGORY="gup_test" run_test ./gup_test -a
+# Dump pages 0, 19, and 4096, using pin_user_pages:
+CATEGORY="gup_test" run_test ./gup_test -ct -F 0x1 0 19 0x1000
+
+uffd_mods=("" ":dev")
+for mod in "${uffd_mods[@]}"; do
+ CATEGORY="userfaultfd" run_test ./userfaultfd anon${mod} 20 16
+ # Hugetlb tests require source and destination huge pages. Pass in half
+ # the size ($half_ufd_size_MB), which is used for *each*.
+ CATEGORY="userfaultfd" run_test ./userfaultfd hugetlb${mod} "$half_ufd_size_MB" 32
+ CATEGORY="userfaultfd" run_test ./userfaultfd hugetlb_shared${mod} "$half_ufd_size_MB" 32
+ CATEGORY="userfaultfd" run_test ./userfaultfd shmem${mod} 20 16
+done
+
+#cleanup
+echo "$nr_hugepgs" > /proc/sys/vm/nr_hugepages
+
+CATEGORY="compaction" run_test ./compaction_test
+
+CATEGORY="mlock" run_test sudo -u nobody ./on-fault-limit
+
+CATEGORY="mmap" run_test ./map_populate
+
+CATEGORY="mlock" run_test ./mlock-random-test
+
+CATEGORY="mlock" run_test ./mlock2-tests
+
+CATEGORY="process_mrelease" run_test ./mrelease_test
+
+CATEGORY="mremap" run_test ./mremap_test
+
+CATEGORY="hugetlb" run_test ./thuge-gen
+
+if [ $VADDR64 -ne 0 ]; then
+ CATEGORY="hugevm" run_test ./virtual_address_range
+
+ # virtual address 128TB switch test
+ CATEGORY="hugevm" run_test ./va_128TBswitch.sh
+fi # VADDR64
+
+# vmalloc stability smoke test
+CATEGORY="vmalloc" run_test ./test_vmalloc.sh smoke
+
+CATEGORY="mremap" run_test ./mremap_dontunmap
+
+CATEGORY="hmm" run_test ./test_hmm.sh smoke
+
+# MADV_POPULATE_READ and MADV_POPULATE_WRITE tests
+CATEGORY="madv_populate" run_test ./madv_populate
+
+CATEGORY="memfd_secret" run_test ./memfd_secret
+
+# KSM MADV_MERGEABLE test with 10 identical pages
+CATEGORY="ksm" run_test ./ksm_tests -M -p 10
+# KSM unmerge test
+CATEGORY="ksm" run_test ./ksm_tests -U
+# KSM test with 10 zero pages and use_zero_pages = 0
+CATEGORY="ksm" run_test ./ksm_tests -Z -p 10 -z 0
+# KSM test with 10 zero pages and use_zero_pages = 1
+CATEGORY="ksm" run_test ./ksm_tests -Z -p 10 -z 1
+# KSM test with 2 NUMA nodes and merge_across_nodes = 1
+CATEGORY="ksm_numa" run_test ./ksm_tests -N -m 1
+# KSM test with 2 NUMA nodes and merge_across_nodes = 0
+CATEGORY="ksm_numa" run_test ./ksm_tests -N -m 0
+
+CATEGORY="ksm" run_test ./ksm_functional_tests
+
+run_test ./ksm_functional_tests
+
+# protection_keys tests
+if [ -x ./protection_keys_32 ]
+then
+ CATEGORY="pkey" run_test ./protection_keys_32
+fi
+
+if [ -x ./protection_keys_64 ]
+then
+ CATEGORY="pkey" run_test ./protection_keys_64
+fi
+
+CATEGORY="soft_dirty" run_test ./soft-dirty
+
+# COW tests
+CATEGORY="cow" run_test ./cow
+
+exit $exitcode
diff --git a/tools/testing/selftests/mm/settings b/tools/testing/selftests/mm/settings
new file mode 100644
index 000000000000..9abfc60e9e6f
--- /dev/null
+++ b/tools/testing/selftests/mm/settings
@@ -0,0 +1 @@
+timeout=45
diff --git a/tools/testing/selftests/mm/soft-dirty.c b/tools/testing/selftests/mm/soft-dirty.c
new file mode 100644
index 000000000000..21d8830c5f24
--- /dev/null
+++ b/tools/testing/selftests/mm/soft-dirty.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <malloc.h>
+#include <sys/mman.h>
+#include "../kselftest.h"
+#include "vm_util.h"
+
+#define PAGEMAP_FILE_PATH "/proc/self/pagemap"
+#define TEST_ITERATIONS 10000
+
+static void test_simple(int pagemap_fd, int pagesize)
+{
+ int i;
+ char *map;
+
+ map = aligned_alloc(pagesize, pagesize);
+ if (!map)
+ ksft_exit_fail_msg("mmap failed\n");
+
+ clear_softdirty();
+
+ for (i = 0 ; i < TEST_ITERATIONS; i++) {
+ if (pagemap_is_softdirty(pagemap_fd, map) == 1) {
+ ksft_print_msg("dirty bit was 1, but should be 0 (i=%d)\n", i);
+ break;
+ }
+
+ clear_softdirty();
+ // Write something to the page to get the dirty bit enabled on the page
+ map[0]++;
+
+ if (pagemap_is_softdirty(pagemap_fd, map) == 0) {
+ ksft_print_msg("dirty bit was 0, but should be 1 (i=%d)\n", i);
+ break;
+ }
+
+ clear_softdirty();
+ }
+ free(map);
+
+ ksft_test_result(i == TEST_ITERATIONS, "Test %s\n", __func__);
+}
+
+static void test_vma_reuse(int pagemap_fd, int pagesize)
+{
+ char *map, *map2;
+
+ map = mmap(NULL, pagesize, (PROT_READ | PROT_WRITE), (MAP_PRIVATE | MAP_ANON), -1, 0);
+ if (map == MAP_FAILED)
+ ksft_exit_fail_msg("mmap failed");
+
+ // The kernel always marks new regions as soft dirty
+ ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 1,
+ "Test %s dirty bit of allocated page\n", __func__);
+
+ clear_softdirty();
+ munmap(map, pagesize);
+
+ map2 = mmap(NULL, pagesize, (PROT_READ | PROT_WRITE), (MAP_PRIVATE | MAP_ANON), -1, 0);
+ if (map2 == MAP_FAILED)
+ ksft_exit_fail_msg("mmap failed");
+
+ // Dirty bit is set for new regions even if they are reused
+ if (map == map2)
+ ksft_test_result(pagemap_is_softdirty(pagemap_fd, map2) == 1,
+ "Test %s dirty bit of reused address page\n", __func__);
+ else
+ ksft_test_result_skip("Test %s dirty bit of reused address page\n", __func__);
+
+ munmap(map2, pagesize);
+}
+
+static void test_hugepage(int pagemap_fd, int pagesize)
+{
+ char *map;
+ int i, ret;
+ size_t hpage_len = read_pmd_pagesize();
+
+ map = memalign(hpage_len, hpage_len);
+ if (!map)
+ ksft_exit_fail_msg("memalign failed\n");
+
+ ret = madvise(map, hpage_len, MADV_HUGEPAGE);
+ if (ret)
+ ksft_exit_fail_msg("madvise failed %d\n", ret);
+
+ for (i = 0; i < hpage_len; i++)
+ map[i] = (char)i;
+
+ if (check_huge_anon(map, 1, hpage_len)) {
+ ksft_test_result_pass("Test %s huge page allocation\n", __func__);
+
+ clear_softdirty();
+ for (i = 0 ; i < TEST_ITERATIONS ; i++) {
+ if (pagemap_is_softdirty(pagemap_fd, map) == 1) {
+ ksft_print_msg("dirty bit was 1, but should be 0 (i=%d)\n", i);
+ break;
+ }
+
+ clear_softdirty();
+ // Write something to the page to get the dirty bit enabled on the page
+ map[0]++;
+
+ if (pagemap_is_softdirty(pagemap_fd, map) == 0) {
+ ksft_print_msg("dirty bit was 0, but should be 1 (i=%d)\n", i);
+ break;
+ }
+ clear_softdirty();
+ }
+
+ ksft_test_result(i == TEST_ITERATIONS, "Test %s huge page dirty bit\n", __func__);
+ } else {
+ // hugepage allocation failed. skip these tests
+ ksft_test_result_skip("Test %s huge page allocation\n", __func__);
+ ksft_test_result_skip("Test %s huge page dirty bit\n", __func__);
+ }
+ free(map);
+}
+
+static void test_mprotect(int pagemap_fd, int pagesize, bool anon)
+{
+ const char *type[] = {"file", "anon"};
+ const char *fname = "./soft-dirty-test-file";
+ int test_fd;
+ char *map;
+
+ if (anon) {
+ map = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
+ MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
+ if (!map)
+ ksft_exit_fail_msg("anon mmap failed\n");
+ } else {
+ test_fd = open(fname, O_RDWR | O_CREAT);
+ if (test_fd < 0) {
+ ksft_test_result_skip("Test %s open() file failed\n", __func__);
+ return;
+ }
+ unlink(fname);
+ ftruncate(test_fd, pagesize);
+ map = mmap(NULL, pagesize, PROT_READ|PROT_WRITE,
+ MAP_SHARED, test_fd, 0);
+ if (!map)
+ ksft_exit_fail_msg("file mmap failed\n");
+ }
+
+ *map = 1;
+ ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 1,
+ "Test %s-%s dirty bit of new written page\n",
+ __func__, type[anon]);
+ clear_softdirty();
+ ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 0,
+ "Test %s-%s soft-dirty clear after clear_refs\n",
+ __func__, type[anon]);
+ mprotect(map, pagesize, PROT_READ);
+ ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 0,
+ "Test %s-%s soft-dirty clear after marking RO\n",
+ __func__, type[anon]);
+ mprotect(map, pagesize, PROT_READ|PROT_WRITE);
+ ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 0,
+ "Test %s-%s soft-dirty clear after marking RW\n",
+ __func__, type[anon]);
+ *map = 2;
+ ksft_test_result(pagemap_is_softdirty(pagemap_fd, map) == 1,
+ "Test %s-%s soft-dirty after rewritten\n",
+ __func__, type[anon]);
+
+ munmap(map, pagesize);
+
+ if (!anon)
+ close(test_fd);
+}
+
+static void test_mprotect_anon(int pagemap_fd, int pagesize)
+{
+ test_mprotect(pagemap_fd, pagesize, true);
+}
+
+static void test_mprotect_file(int pagemap_fd, int pagesize)
+{
+ test_mprotect(pagemap_fd, pagesize, false);
+}
+
+int main(int argc, char **argv)
+{
+ int pagemap_fd;
+ int pagesize;
+
+ ksft_print_header();
+ ksft_set_plan(15);
+
+ pagemap_fd = open(PAGEMAP_FILE_PATH, O_RDONLY);
+ if (pagemap_fd < 0)
+ ksft_exit_fail_msg("Failed to open %s\n", PAGEMAP_FILE_PATH);
+
+ pagesize = getpagesize();
+
+ test_simple(pagemap_fd, pagesize);
+ test_vma_reuse(pagemap_fd, pagesize);
+ test_hugepage(pagemap_fd, pagesize);
+ test_mprotect_anon(pagemap_fd, pagesize);
+ test_mprotect_file(pagemap_fd, pagesize);
+
+ close(pagemap_fd);
+
+ return ksft_exit_pass();
+}
diff --git a/tools/testing/selftests/mm/split_huge_page_test.c b/tools/testing/selftests/mm/split_huge_page_test.c
new file mode 100644
index 000000000000..76e1c36dd9e5
--- /dev/null
+++ b/tools/testing/selftests/mm/split_huge_page_test.c
@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * A test of splitting PMD THPs and PTE-mapped THPs from a specified virtual
+ * address range in a process via <debugfs>/split_huge_pages interface.
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/mount.h>
+#include <malloc.h>
+#include <stdbool.h>
+#include "vm_util.h"
+
+uint64_t pagesize;
+unsigned int pageshift;
+uint64_t pmd_pagesize;
+
+#define SPLIT_DEBUGFS "/sys/kernel/debug/split_huge_pages"
+#define INPUT_MAX 80
+
+#define PID_FMT "%d,0x%lx,0x%lx"
+#define PATH_FMT "%s,0x%lx,0x%lx"
+
+#define PFN_MASK ((1UL<<55)-1)
+#define KPF_THP (1UL<<22)
+
+int is_backed_by_thp(char *vaddr, int pagemap_file, int kpageflags_file)
+{
+ uint64_t paddr;
+ uint64_t page_flags;
+
+ if (pagemap_file) {
+ pread(pagemap_file, &paddr, sizeof(paddr),
+ ((long)vaddr >> pageshift) * sizeof(paddr));
+
+ if (kpageflags_file) {
+ pread(kpageflags_file, &page_flags, sizeof(page_flags),
+ (paddr & PFN_MASK) * sizeof(page_flags));
+
+ return !!(page_flags & KPF_THP);
+ }
+ }
+ return 0;
+}
+
+static int write_file(const char *path, const char *buf, size_t buflen)
+{
+ int fd;
+ ssize_t numwritten;
+
+ fd = open(path, O_WRONLY);
+ if (fd == -1)
+ return 0;
+
+ numwritten = write(fd, buf, buflen - 1);
+ close(fd);
+ if (numwritten < 1)
+ return 0;
+
+ return (unsigned int) numwritten;
+}
+
+static void write_debugfs(const char *fmt, ...)
+{
+ char input[INPUT_MAX];
+ int ret;
+ va_list argp;
+
+ va_start(argp, fmt);
+ ret = vsnprintf(input, INPUT_MAX, fmt, argp);
+ va_end(argp);
+
+ if (ret >= INPUT_MAX) {
+ printf("%s: Debugfs input is too long\n", __func__);
+ exit(EXIT_FAILURE);
+ }
+
+ if (!write_file(SPLIT_DEBUGFS, input, ret + 1)) {
+ perror(SPLIT_DEBUGFS);
+ exit(EXIT_FAILURE);
+ }
+}
+
+void split_pmd_thp(void)
+{
+ char *one_page;
+ size_t len = 4 * pmd_pagesize;
+ size_t i;
+
+ one_page = memalign(pmd_pagesize, len);
+
+ if (!one_page) {
+ printf("Fail to allocate memory\n");
+ exit(EXIT_FAILURE);
+ }
+
+ madvise(one_page, len, MADV_HUGEPAGE);
+
+ for (i = 0; i < len; i++)
+ one_page[i] = (char)i;
+
+ if (!check_huge_anon(one_page, 1, pmd_pagesize)) {
+ printf("No THP is allocated\n");
+ exit(EXIT_FAILURE);
+ }
+
+ /* split all THPs */
+ write_debugfs(PID_FMT, getpid(), (uint64_t)one_page,
+ (uint64_t)one_page + len);
+
+ for (i = 0; i < len; i++)
+ if (one_page[i] != (char)i) {
+ printf("%ld byte corrupted\n", i);
+ exit(EXIT_FAILURE);
+ }
+
+
+ if (check_huge_anon(one_page, 0, pmd_pagesize)) {
+ printf("Still AnonHugePages not split\n");
+ exit(EXIT_FAILURE);
+ }
+
+ printf("Split huge pages successful\n");
+ free(one_page);
+}
+
+void split_pte_mapped_thp(void)
+{
+ char *one_page, *pte_mapped, *pte_mapped2;
+ size_t len = 4 * pmd_pagesize;
+ uint64_t thp_size;
+ size_t i;
+ const char *pagemap_template = "/proc/%d/pagemap";
+ const char *kpageflags_proc = "/proc/kpageflags";
+ char pagemap_proc[255];
+ int pagemap_fd;
+ int kpageflags_fd;
+
+ if (snprintf(pagemap_proc, 255, pagemap_template, getpid()) < 0) {
+ perror("get pagemap proc error");
+ exit(EXIT_FAILURE);
+ }
+ pagemap_fd = open(pagemap_proc, O_RDONLY);
+
+ if (pagemap_fd == -1) {
+ perror("read pagemap:");
+ exit(EXIT_FAILURE);
+ }
+
+ kpageflags_fd = open(kpageflags_proc, O_RDONLY);
+
+ if (kpageflags_fd == -1) {
+ perror("read kpageflags:");
+ exit(EXIT_FAILURE);
+ }
+
+ one_page = mmap((void *)(1UL << 30), len, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+
+ madvise(one_page, len, MADV_HUGEPAGE);
+
+ for (i = 0; i < len; i++)
+ one_page[i] = (char)i;
+
+ if (!check_huge_anon(one_page, 1, pmd_pagesize)) {
+ printf("No THP is allocated\n");
+ exit(EXIT_FAILURE);
+ }
+
+ /* remap the first pagesize of first THP */
+ pte_mapped = mremap(one_page, pagesize, pagesize, MREMAP_MAYMOVE);
+
+ /* remap the Nth pagesize of Nth THP */
+ for (i = 1; i < 4; i++) {
+ pte_mapped2 = mremap(one_page + pmd_pagesize * i + pagesize * i,
+ pagesize, pagesize,
+ MREMAP_MAYMOVE|MREMAP_FIXED,
+ pte_mapped + pagesize * i);
+ if (pte_mapped2 == (char *)-1) {
+ perror("mremap failed");
+ exit(EXIT_FAILURE);
+ }
+ }
+
+ /* smap does not show THPs after mremap, use kpageflags instead */
+ thp_size = 0;
+ for (i = 0; i < pagesize * 4; i++)
+ if (i % pagesize == 0 &&
+ is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd))
+ thp_size++;
+
+ if (thp_size != 4) {
+ printf("Some THPs are missing during mremap\n");
+ exit(EXIT_FAILURE);
+ }
+
+ /* split all remapped THPs */
+ write_debugfs(PID_FMT, getpid(), (uint64_t)pte_mapped,
+ (uint64_t)pte_mapped + pagesize * 4);
+
+ /* smap does not show THPs after mremap, use kpageflags instead */
+ thp_size = 0;
+ for (i = 0; i < pagesize * 4; i++) {
+ if (pte_mapped[i] != (char)i) {
+ printf("%ld byte corrupted\n", i);
+ exit(EXIT_FAILURE);
+ }
+ if (i % pagesize == 0 &&
+ is_backed_by_thp(&pte_mapped[i], pagemap_fd, kpageflags_fd))
+ thp_size++;
+ }
+
+ if (thp_size) {
+ printf("Still %ld THPs not split\n", thp_size);
+ exit(EXIT_FAILURE);
+ }
+
+ printf("Split PTE-mapped huge pages successful\n");
+ munmap(one_page, len);
+ close(pagemap_fd);
+ close(kpageflags_fd);
+}
+
+void split_file_backed_thp(void)
+{
+ int status;
+ int fd;
+ ssize_t num_written;
+ char tmpfs_template[] = "/tmp/thp_split_XXXXXX";
+ const char *tmpfs_loc = mkdtemp(tmpfs_template);
+ char testfile[INPUT_MAX];
+ uint64_t pgoff_start = 0, pgoff_end = 1024;
+
+ printf("Please enable pr_debug in split_huge_pages_in_file() if you need more info.\n");
+
+ status = mount("tmpfs", tmpfs_loc, "tmpfs", 0, "huge=always,size=4m");
+
+ if (status) {
+ printf("Unable to create a tmpfs for testing\n");
+ exit(EXIT_FAILURE);
+ }
+
+ status = snprintf(testfile, INPUT_MAX, "%s/thp_file", tmpfs_loc);
+ if (status >= INPUT_MAX) {
+ printf("Fail to create file-backed THP split testing file\n");
+ goto cleanup;
+ }
+
+ fd = open(testfile, O_CREAT|O_WRONLY);
+ if (fd == -1) {
+ perror("Cannot open testing file\n");
+ goto cleanup;
+ }
+
+ /* write something to the file, so a file-backed THP can be allocated */
+ num_written = write(fd, tmpfs_loc, strlen(tmpfs_loc) + 1);
+ close(fd);
+
+ if (num_written < 1) {
+ printf("Fail to write data to testing file\n");
+ goto cleanup;
+ }
+
+ /* split the file-backed THP */
+ write_debugfs(PATH_FMT, testfile, pgoff_start, pgoff_end);
+
+ status = unlink(testfile);
+ if (status)
+ perror("Cannot remove testing file\n");
+
+cleanup:
+ status = umount(tmpfs_loc);
+ if (status) {
+ printf("Unable to umount %s\n", tmpfs_loc);
+ exit(EXIT_FAILURE);
+ }
+ status = rmdir(tmpfs_loc);
+ if (status) {
+ perror("cannot remove tmp dir");
+ exit(EXIT_FAILURE);
+ }
+
+ printf("file-backed THP split test done, please check dmesg for more information\n");
+}
+
+int main(int argc, char **argv)
+{
+ if (geteuid() != 0) {
+ printf("Please run the benchmark as root\n");
+ exit(EXIT_FAILURE);
+ }
+
+ pagesize = getpagesize();
+ pageshift = ffs(pagesize) - 1;
+ pmd_pagesize = read_pmd_pagesize();
+
+ split_pmd_thp();
+ split_pte_mapped_thp();
+ split_file_backed_thp();
+
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/test_hmm.sh b/tools/testing/selftests/mm/test_hmm.sh
new file mode 100644
index 000000000000..46e19b5d648d
--- /dev/null
+++ b/tools/testing/selftests/mm/test_hmm.sh
@@ -0,0 +1,105 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (C) 2018 Uladzislau Rezki (Sony) <urezki@gmail.com>
+#
+# This is a test script for the kernel test driver to analyse vmalloc
+# allocator. Therefore it is just a kernel module loader. You can specify
+# and pass different parameters in order to:
+# a) analyse performance of vmalloc allocations;
+# b) stressing and stability check of vmalloc subsystem.
+
+TEST_NAME="test_hmm"
+DRIVER="test_hmm"
+
+# 1 if fails
+exitcode=1
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+check_test_requirements()
+{
+ uid=$(id -u)
+ if [ $uid -ne 0 ]; then
+ echo "$0: Must be run as root"
+ exit $ksft_skip
+ fi
+
+ if ! which modprobe > /dev/null 2>&1; then
+ echo "$0: You need modprobe installed"
+ exit $ksft_skip
+ fi
+
+ if ! modinfo $DRIVER > /dev/null 2>&1; then
+ echo "$0: You must have the following enabled in your kernel:"
+ echo "CONFIG_TEST_HMM=m"
+ exit $ksft_skip
+ fi
+}
+
+load_driver()
+{
+ if [ $# -eq 0 ]; then
+ modprobe $DRIVER > /dev/null 2>&1
+ else
+ if [ $# -eq 2 ]; then
+ modprobe $DRIVER spm_addr_dev0=$1 spm_addr_dev1=$2
+ > /dev/null 2>&1
+ else
+ echo "Missing module parameters. Make sure pass"\
+ "spm_addr_dev0 and spm_addr_dev1"
+ usage
+ fi
+ fi
+}
+
+unload_driver()
+{
+ modprobe -r $DRIVER > /dev/null 2>&1
+}
+
+run_smoke()
+{
+ echo "Running smoke test. Note, this test provides basic coverage."
+
+ load_driver $1 $2
+ $(dirname "${BASH_SOURCE[0]}")/hmm-tests
+ unload_driver
+}
+
+usage()
+{
+ echo -n "Usage: $0"
+ echo
+ echo "Example usage:"
+ echo
+ echo "# Shows help message"
+ echo "./${TEST_NAME}.sh"
+ echo
+ echo "# Smoke testing"
+ echo "./${TEST_NAME}.sh smoke"
+ echo
+ echo "# Smoke testing with SPM enabled"
+ echo "./${TEST_NAME}.sh smoke <spm_addr_dev0> <spm_addr_dev1>"
+ echo
+ exit 0
+}
+
+function run_test()
+{
+ if [ $# -eq 0 ]; then
+ usage
+ else
+ if [ "$1" = "smoke" ]; then
+ run_smoke $2 $3
+ else
+ usage
+ fi
+ fi
+}
+
+check_test_requirements
+run_test $@
+
+exit 0
diff --git a/tools/testing/selftests/mm/test_vmalloc.sh b/tools/testing/selftests/mm/test_vmalloc.sh
new file mode 100644
index 000000000000..d73b846736f1
--- /dev/null
+++ b/tools/testing/selftests/mm/test_vmalloc.sh
@@ -0,0 +1,177 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (C) 2018 Uladzislau Rezki (Sony) <urezki@gmail.com>
+#
+# This is a test script for the kernel test driver to analyse vmalloc
+# allocator. Therefore it is just a kernel module loader. You can specify
+# and pass different parameters in order to:
+# a) analyse performance of vmalloc allocations;
+# b) stressing and stability check of vmalloc subsystem.
+
+TEST_NAME="vmalloc"
+DRIVER="test_${TEST_NAME}"
+NUM_CPUS=`grep -c ^processor /proc/cpuinfo`
+
+# 1 if fails
+exitcode=1
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+#
+# Static templates for performance, stressing and smoke tests.
+# Also it is possible to pass any supported parameters manualy.
+#
+PERF_PARAM="sequential_test_order=1 test_repeat_count=3"
+SMOKE_PARAM="test_loop_count=10000 test_repeat_count=10"
+STRESS_PARAM="nr_threads=$NUM_CPUS test_repeat_count=20"
+
+check_test_requirements()
+{
+ uid=$(id -u)
+ if [ $uid -ne 0 ]; then
+ echo "$0: Must be run as root"
+ exit $ksft_skip
+ fi
+
+ if ! which modprobe > /dev/null 2>&1; then
+ echo "$0: You need modprobe installed"
+ exit $ksft_skip
+ fi
+
+ if ! modinfo $DRIVER > /dev/null 2>&1; then
+ echo "$0: You must have the following enabled in your kernel:"
+ echo "CONFIG_TEST_VMALLOC=m"
+ exit $ksft_skip
+ fi
+}
+
+run_perfformance_check()
+{
+ echo "Run performance tests to evaluate how fast vmalloc allocation is."
+ echo "It runs all test cases on one single CPU with sequential order."
+
+ modprobe $DRIVER $PERF_PARAM > /dev/null 2>&1
+ echo "Done."
+ echo "Ccheck the kernel message buffer to see the summary."
+}
+
+run_stability_check()
+{
+ echo "Run stability tests. In order to stress vmalloc subsystem all"
+ echo "available test cases are run by NUM_CPUS workers simultaneously."
+ echo "It will take time, so be patient."
+
+ modprobe $DRIVER $STRESS_PARAM > /dev/null 2>&1
+ echo "Done."
+ echo "Check the kernel ring buffer to see the summary."
+}
+
+run_smoke_check()
+{
+ echo "Run smoke test. Note, this test provides basic coverage."
+ echo "Please check $0 output how it can be used"
+ echo "for deep performance analysis as well as stress testing."
+
+ modprobe $DRIVER $SMOKE_PARAM > /dev/null 2>&1
+ echo "Done."
+ echo "Check the kernel ring buffer to see the summary."
+}
+
+usage()
+{
+ echo -n "Usage: $0 [ performance ] | [ stress ] | | [ smoke ] | "
+ echo "manual parameters"
+ echo
+ echo "Valid tests and parameters:"
+ echo
+ modinfo $DRIVER
+ echo
+ echo "Example usage:"
+ echo
+ echo "# Shows help message"
+ echo "./${DRIVER}.sh"
+ echo
+ echo "# Runs 1 test(id_1), repeats it 5 times by NUM_CPUS workers"
+ echo "./${DRIVER}.sh nr_threads=$NUM_CPUS run_test_mask=1 test_repeat_count=5"
+ echo
+ echo -n "# Runs 4 tests(id_1|id_2|id_4|id_16) on one CPU with "
+ echo "sequential order"
+ echo -n "./${DRIVER}.sh sequential_test_order=1 "
+ echo "run_test_mask=23"
+ echo
+ echo -n "# Runs all tests by NUM_CPUS workers, shuffled order, repeats "
+ echo "20 times"
+ echo "./${DRIVER}.sh nr_threads=$NUM_CPUS test_repeat_count=20"
+ echo
+ echo "# Performance analysis"
+ echo "./${DRIVER}.sh performance"
+ echo
+ echo "# Stress testing"
+ echo "./${DRIVER}.sh stress"
+ echo
+ exit 0
+}
+
+function validate_passed_args()
+{
+ VALID_ARGS=`modinfo $DRIVER | awk '/parm:/ {print $2}' | sed 's/:.*//'`
+
+ #
+ # Something has been passed, check it.
+ #
+ for passed_arg in $@; do
+ key=${passed_arg//=*/}
+ val="${passed_arg:$((${#key}+1))}"
+ valid=0
+
+ for valid_arg in $VALID_ARGS; do
+ if [[ $key = $valid_arg ]] && [[ $val -gt 0 ]]; then
+ valid=1
+ break
+ fi
+ done
+
+ if [[ $valid -ne 1 ]]; then
+ echo "Error: key or value is not correct: ${key} $val"
+ exit $exitcode
+ fi
+ done
+}
+
+function run_manual_check()
+{
+ #
+ # Validate passed parameters. If there is wrong one,
+ # the script exists and does not execute further.
+ #
+ validate_passed_args $@
+
+ echo "Run the test with following parameters: $@"
+ modprobe $DRIVER $@ > /dev/null 2>&1
+ echo "Done."
+ echo "Check the kernel ring buffer to see the summary."
+}
+
+function run_test()
+{
+ if [ $# -eq 0 ]; then
+ usage
+ else
+ if [[ "$1" = "performance" ]]; then
+ run_perfformance_check
+ elif [[ "$1" = "stress" ]]; then
+ run_stability_check
+ elif [[ "$1" = "smoke" ]]; then
+ run_smoke_check
+ else
+ run_manual_check $@
+ fi
+ fi
+}
+
+check_test_requirements
+run_test $@
+
+exit 0
diff --git a/tools/testing/selftests/mm/thuge-gen.c b/tools/testing/selftests/mm/thuge-gen.c
new file mode 100644
index 000000000000..361ef7192cc6
--- /dev/null
+++ b/tools/testing/selftests/mm/thuge-gen.c
@@ -0,0 +1,257 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Test selecting other page sizes for mmap/shmget.
+
+ Before running this huge pages for each huge page size must have been
+ reserved.
+ For large pages beyond MAX_ORDER (like 1GB on x86) boot options must be used.
+ Also shmmax must be increased.
+ And you need to run as root to work around some weird permissions in shm.
+ And nothing using huge pages should run in parallel.
+ When the program aborts you may need to clean up the shm segments with
+ ipcrm -m by hand, like this
+ sudo ipcs | awk '$1 == "0x00000000" {print $2}' | xargs -n1 sudo ipcrm -m
+ (warning this will remove all if someone else uses them) */
+
+#define _GNU_SOURCE 1
+#include <sys/mman.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#include <sys/stat.h>
+#include <glob.h>
+#include <assert.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <string.h>
+
+#define err(x) perror(x), exit(1)
+
+#define MAP_HUGE_2MB (21 << MAP_HUGE_SHIFT)
+#define MAP_HUGE_1GB (30 << MAP_HUGE_SHIFT)
+#define MAP_HUGE_SHIFT 26
+#define MAP_HUGE_MASK 0x3f
+#if !defined(MAP_HUGETLB)
+#define MAP_HUGETLB 0x40000
+#endif
+
+#define SHM_HUGETLB 04000 /* segment will use huge TLB pages */
+#define SHM_HUGE_SHIFT 26
+#define SHM_HUGE_MASK 0x3f
+#define SHM_HUGE_2MB (21 << SHM_HUGE_SHIFT)
+#define SHM_HUGE_1GB (30 << SHM_HUGE_SHIFT)
+
+#define NUM_PAGESIZES 5
+
+#define NUM_PAGES 4
+
+#define Dprintf(fmt...) // printf(fmt)
+
+unsigned long page_sizes[NUM_PAGESIZES];
+int num_page_sizes;
+
+int ilog2(unsigned long v)
+{
+ int l = 0;
+ while ((1UL << l) < v)
+ l++;
+ return l;
+}
+
+void find_pagesizes(void)
+{
+ glob_t g;
+ int i;
+ glob("/sys/kernel/mm/hugepages/hugepages-*kB", 0, NULL, &g);
+ assert(g.gl_pathc <= NUM_PAGESIZES);
+ for (i = 0; i < g.gl_pathc; i++) {
+ sscanf(g.gl_pathv[i], "/sys/kernel/mm/hugepages/hugepages-%lukB",
+ &page_sizes[i]);
+ page_sizes[i] <<= 10;
+ printf("Found %luMB\n", page_sizes[i] >> 20);
+ }
+ num_page_sizes = g.gl_pathc;
+ globfree(&g);
+}
+
+unsigned long default_huge_page_size(void)
+{
+ unsigned long hps = 0;
+ char *line = NULL;
+ size_t linelen = 0;
+ FILE *f = fopen("/proc/meminfo", "r");
+ if (!f)
+ return 0;
+ while (getline(&line, &linelen, f) > 0) {
+ if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) {
+ hps <<= 10;
+ break;
+ }
+ }
+ free(line);
+ return hps;
+}
+
+void show(unsigned long ps)
+{
+ char buf[100];
+ if (ps == getpagesize())
+ return;
+ printf("%luMB: ", ps >> 20);
+ fflush(stdout);
+ snprintf(buf, sizeof buf,
+ "cat /sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages",
+ ps >> 10);
+ system(buf);
+}
+
+unsigned long read_sysfs(int warn, char *fmt, ...)
+{
+ char *line = NULL;
+ size_t linelen = 0;
+ char buf[100];
+ FILE *f;
+ va_list ap;
+ unsigned long val = 0;
+
+ va_start(ap, fmt);
+ vsnprintf(buf, sizeof buf, fmt, ap);
+ va_end(ap);
+
+ f = fopen(buf, "r");
+ if (!f) {
+ if (warn)
+ printf("missing %s\n", buf);
+ return 0;
+ }
+ if (getline(&line, &linelen, f) > 0) {
+ sscanf(line, "%lu", &val);
+ }
+ fclose(f);
+ free(line);
+ return val;
+}
+
+unsigned long read_free(unsigned long ps)
+{
+ return read_sysfs(ps != getpagesize(),
+ "/sys/kernel/mm/hugepages/hugepages-%lukB/free_hugepages",
+ ps >> 10);
+}
+
+void test_mmap(unsigned long size, unsigned flags)
+{
+ char *map;
+ unsigned long before, after;
+ int err;
+
+ before = read_free(size);
+ map = mmap(NULL, size*NUM_PAGES, PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_ANONYMOUS|MAP_HUGETLB|flags, -1, 0);
+
+ if (map == (char *)-1) err("mmap");
+ memset(map, 0xff, size*NUM_PAGES);
+ after = read_free(size);
+ Dprintf("before %lu after %lu diff %ld size %lu\n",
+ before, after, before - after, size);
+ assert(size == getpagesize() || (before - after) == NUM_PAGES);
+ show(size);
+ err = munmap(map, size);
+ assert(!err);
+}
+
+void test_shmget(unsigned long size, unsigned flags)
+{
+ int id;
+ unsigned long before, after;
+ int err;
+
+ before = read_free(size);
+ id = shmget(IPC_PRIVATE, size * NUM_PAGES, IPC_CREAT|0600|flags);
+ if (id < 0) err("shmget");
+
+ struct shm_info i;
+ if (shmctl(id, SHM_INFO, (void *)&i) < 0) err("shmctl");
+ Dprintf("alloc %lu res %lu\n", i.shm_tot, i.shm_rss);
+
+
+ Dprintf("id %d\n", id);
+ char *map = shmat(id, NULL, 0600);
+ if (map == (char*)-1) err("shmat");
+
+ shmctl(id, IPC_RMID, NULL);
+
+ memset(map, 0xff, size*NUM_PAGES);
+ after = read_free(size);
+
+ Dprintf("before %lu after %lu diff %ld size %lu\n",
+ before, after, before - after, size);
+ assert(size == getpagesize() || (before - after) == NUM_PAGES);
+ show(size);
+ err = shmdt(map);
+ assert(!err);
+}
+
+void sanity_checks(void)
+{
+ int i;
+ unsigned long largest = getpagesize();
+
+ for (i = 0; i < num_page_sizes; i++) {
+ if (page_sizes[i] > largest)
+ largest = page_sizes[i];
+
+ if (read_free(page_sizes[i]) < NUM_PAGES) {
+ printf("Not enough huge pages for page size %lu MB, need %u\n",
+ page_sizes[i] >> 20,
+ NUM_PAGES);
+ exit(0);
+ }
+ }
+
+ if (read_sysfs(0, "/proc/sys/kernel/shmmax") < NUM_PAGES * largest) {
+ printf("Please do echo %lu > /proc/sys/kernel/shmmax", largest * NUM_PAGES);
+ exit(0);
+ }
+
+#if defined(__x86_64__)
+ if (largest != 1U<<30) {
+ printf("No GB pages available on x86-64\n"
+ "Please boot with hugepagesz=1G hugepages=%d\n", NUM_PAGES);
+ exit(0);
+ }
+#endif
+}
+
+int main(void)
+{
+ int i;
+ unsigned default_hps = default_huge_page_size();
+
+ find_pagesizes();
+
+ sanity_checks();
+
+ for (i = 0; i < num_page_sizes; i++) {
+ unsigned long ps = page_sizes[i];
+ int arg = ilog2(ps) << MAP_HUGE_SHIFT;
+ printf("Testing %luMB mmap with shift %x\n", ps >> 20, arg);
+ test_mmap(ps, MAP_HUGETLB | arg);
+ }
+ printf("Testing default huge mmap\n");
+ test_mmap(default_hps, SHM_HUGETLB);
+
+ puts("Testing non-huge shmget");
+ test_shmget(getpagesize(), 0);
+
+ for (i = 0; i < num_page_sizes; i++) {
+ unsigned long ps = page_sizes[i];
+ int arg = ilog2(ps) << SHM_HUGE_SHIFT;
+ printf("Testing %luMB shmget with shift %x\n", ps >> 20, arg);
+ test_shmget(ps, SHM_HUGETLB | arg);
+ }
+ puts("default huge shmget");
+ test_shmget(default_hps, SHM_HUGETLB);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/transhuge-stress.c b/tools/testing/selftests/mm/transhuge-stress.c
new file mode 100644
index 000000000000..e3f00adb1b82
--- /dev/null
+++ b/tools/testing/selftests/mm/transhuge-stress.c
@@ -0,0 +1,122 @@
+/*
+ * Stress test for transparent huge pages, memory compaction and migration.
+ *
+ * Authors: Konstantin Khlebnikov <koct9i@gmail.com>
+ *
+ * This is free and unencumbered software released into the public domain.
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <err.h>
+#include <time.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/mman.h>
+#include "util.h"
+
+int backing_fd = -1;
+int mmap_flags = MAP_ANONYMOUS | MAP_NORESERVE | MAP_PRIVATE;
+#define PROT_RW (PROT_READ | PROT_WRITE)
+
+int main(int argc, char **argv)
+{
+ size_t ram, len;
+ void *ptr, *p;
+ struct timespec a, b;
+ int i = 0;
+ char *name = NULL;
+ double s;
+ uint8_t *map;
+ size_t map_len;
+ int pagemap_fd;
+
+ ram = sysconf(_SC_PHYS_PAGES);
+ if (ram > SIZE_MAX / sysconf(_SC_PAGESIZE) / 4)
+ ram = SIZE_MAX / 4;
+ else
+ ram *= sysconf(_SC_PAGESIZE);
+ len = ram;
+
+ while (++i < argc) {
+ if (!strcmp(argv[i], "-h"))
+ errx(1, "usage: %s [size in MiB]", argv[0]);
+ else if (!strcmp(argv[i], "-f"))
+ name = argv[++i];
+ else
+ len = atoll(argv[i]) << 20;
+ }
+
+ if (name) {
+ backing_fd = open(name, O_RDWR);
+ if (backing_fd == -1)
+ errx(2, "open %s", name);
+ mmap_flags = MAP_SHARED;
+ }
+
+ warnx("allocate %zd transhuge pages, using %zd MiB virtual memory"
+ " and %zd MiB of ram", len >> HPAGE_SHIFT, len >> 20,
+ ram >> (20 + HPAGE_SHIFT - PAGE_SHIFT - 1));
+
+ pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
+ if (pagemap_fd < 0)
+ err(2, "open pagemap");
+
+ len -= len % HPAGE_SIZE;
+ ptr = mmap(NULL, len + HPAGE_SIZE, PROT_RW, mmap_flags, backing_fd, 0);
+ if (ptr == MAP_FAILED)
+ err(2, "initial mmap");
+ ptr += HPAGE_SIZE - (uintptr_t)ptr % HPAGE_SIZE;
+
+ if (madvise(ptr, len, MADV_HUGEPAGE))
+ err(2, "MADV_HUGEPAGE");
+
+ map_len = ram >> (HPAGE_SHIFT - 1);
+ map = malloc(map_len);
+ if (!map)
+ errx(2, "map malloc");
+
+ while (1) {
+ int nr_succeed = 0, nr_failed = 0, nr_pages = 0;
+
+ memset(map, 0, map_len);
+
+ clock_gettime(CLOCK_MONOTONIC, &a);
+ for (p = ptr; p < ptr + len; p += HPAGE_SIZE) {
+ int64_t pfn;
+
+ pfn = allocate_transhuge(p, pagemap_fd);
+
+ if (pfn < 0) {
+ nr_failed++;
+ } else {
+ size_t idx = pfn >> (HPAGE_SHIFT - PAGE_SHIFT);
+
+ nr_succeed++;
+ if (idx >= map_len) {
+ map = realloc(map, idx + 1);
+ if (!map)
+ errx(2, "map realloc");
+ memset(map + map_len, 0, idx + 1 - map_len);
+ map_len = idx + 1;
+ }
+ if (!map[idx])
+ nr_pages++;
+ map[idx] = 1;
+ }
+
+ /* split transhuge page, keep last page */
+ if (madvise(p, HPAGE_SIZE - PAGE_SIZE, MADV_DONTNEED))
+ err(2, "MADV_DONTNEED");
+ }
+ clock_gettime(CLOCK_MONOTONIC, &b);
+ s = b.tv_sec - a.tv_sec + (b.tv_nsec - a.tv_nsec) / 1000000000.;
+
+ warnx("%.3f s/loop, %.3f ms/page, %10.3f MiB/s\t"
+ "%4d succeed, %4d failed, %4d different pages",
+ s, s * 1000 / (len >> HPAGE_SHIFT), len / s / (1 << 20),
+ nr_succeed, nr_failed, nr_pages);
+ }
+}
diff --git a/tools/testing/selftests/mm/userfaultfd.c b/tools/testing/selftests/mm/userfaultfd.c
new file mode 100644
index 000000000000..7f22844ed704
--- /dev/null
+++ b/tools/testing/selftests/mm/userfaultfd.c
@@ -0,0 +1,1858 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Stress userfaultfd syscall.
+ *
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * This test allocates two virtual areas and bounces the physical
+ * memory across the two virtual areas (from area_src to area_dst)
+ * using userfaultfd.
+ *
+ * There are three threads running per CPU:
+ *
+ * 1) one per-CPU thread takes a per-page pthread_mutex in a random
+ * page of the area_dst (while the physical page may still be in
+ * area_src), and increments a per-page counter in the same page,
+ * and checks its value against a verification region.
+ *
+ * 2) another per-CPU thread handles the userfaults generated by
+ * thread 1 above. userfaultfd blocking reads or poll() modes are
+ * exercised interleaved.
+ *
+ * 3) one last per-CPU thread transfers the memory in the background
+ * at maximum bandwidth (if not already transferred by thread
+ * 2). Each cpu thread takes cares of transferring a portion of the
+ * area.
+ *
+ * When all threads of type 3 completed the transfer, one bounce is
+ * complete. area_src and area_dst are then swapped. All threads are
+ * respawned and so the bounce is immediately restarted in the
+ * opposite direction.
+ *
+ * per-CPU threads 1 by triggering userfaults inside
+ * pthread_mutex_lock will also verify the atomicity of the memory
+ * transfer (UFFDIO_COPY).
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <time.h>
+#include <signal.h>
+#include <poll.h>
+#include <string.h>
+#include <linux/mman.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#include <sys/ioctl.h>
+#include <sys/wait.h>
+#include <pthread.h>
+#include <linux/userfaultfd.h>
+#include <setjmp.h>
+#include <stdbool.h>
+#include <assert.h>
+#include <inttypes.h>
+#include <stdint.h>
+#include <sys/random.h>
+
+#include "../kselftest.h"
+#include "vm_util.h"
+
+#ifdef __NR_userfaultfd
+
+static unsigned long nr_cpus, nr_pages, nr_pages_per_cpu, page_size, hpage_size;
+
+#define BOUNCE_RANDOM (1<<0)
+#define BOUNCE_RACINGFAULTS (1<<1)
+#define BOUNCE_VERIFY (1<<2)
+#define BOUNCE_POLL (1<<3)
+static int bounces;
+
+#define TEST_ANON 1
+#define TEST_HUGETLB 2
+#define TEST_SHMEM 3
+static int test_type;
+
+#define UFFD_FLAGS (O_CLOEXEC | O_NONBLOCK | UFFD_USER_MODE_ONLY)
+
+#define BASE_PMD_ADDR ((void *)(1UL << 30))
+
+/* test using /dev/userfaultfd, instead of userfaultfd(2) */
+static bool test_dev_userfaultfd;
+
+/* exercise the test_uffdio_*_eexist every ALARM_INTERVAL_SECS */
+#define ALARM_INTERVAL_SECS 10
+static volatile bool test_uffdio_copy_eexist = true;
+static volatile bool test_uffdio_zeropage_eexist = true;
+/* Whether to test uffd write-protection */
+static bool test_uffdio_wp = true;
+/* Whether to test uffd minor faults */
+static bool test_uffdio_minor = false;
+static bool map_shared;
+static int mem_fd;
+static unsigned long long *count_verify;
+static int uffd = -1;
+static int uffd_flags, finished, *pipefd;
+static char *area_src, *area_src_alias, *area_dst, *area_dst_alias, *area_remap;
+static char *zeropage;
+pthread_attr_t attr;
+static bool test_collapse;
+
+/* Userfaultfd test statistics */
+struct uffd_stats {
+ int cpu;
+ unsigned long missing_faults;
+ unsigned long wp_faults;
+ unsigned long minor_faults;
+};
+
+/* pthread_mutex_t starts at page offset 0 */
+#define area_mutex(___area, ___nr) \
+ ((pthread_mutex_t *) ((___area) + (___nr)*page_size))
+/*
+ * count is placed in the page after pthread_mutex_t naturally aligned
+ * to avoid non alignment faults on non-x86 archs.
+ */
+#define area_count(___area, ___nr) \
+ ((volatile unsigned long long *) ((unsigned long) \
+ ((___area) + (___nr)*page_size + \
+ sizeof(pthread_mutex_t) + \
+ sizeof(unsigned long long) - 1) & \
+ ~(unsigned long)(sizeof(unsigned long long) \
+ - 1)))
+
+#define swap(a, b) \
+ do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
+
+#define factor_of_2(x) ((x) ^ ((x) & ((x) - 1)))
+
+const char *examples =
+ "# Run anonymous memory test on 100MiB region with 99999 bounces:\n"
+ "./userfaultfd anon 100 99999\n\n"
+ "# Run the same anonymous memory test, but using /dev/userfaultfd:\n"
+ "./userfaultfd anon:dev 100 99999\n\n"
+ "# Run share memory test on 1GiB region with 99 bounces:\n"
+ "./userfaultfd shmem 1000 99\n\n"
+ "# Run hugetlb memory test on 256MiB region with 50 bounces:\n"
+ "./userfaultfd hugetlb 256 50\n\n"
+ "# Run the same hugetlb test but using shared file:\n"
+ "./userfaultfd hugetlb_shared 256 50\n\n"
+ "# 10MiB-~6GiB 999 bounces anonymous test, "
+ "continue forever unless an error triggers\n"
+ "while ./userfaultfd anon $[RANDOM % 6000 + 10] 999; do true; done\n\n";
+
+static void usage(void)
+{
+ fprintf(stderr, "\nUsage: ./userfaultfd <test type> <MiB> <bounces> "
+ "[hugetlbfs_file]\n\n");
+ fprintf(stderr, "Supported <test type>: anon, hugetlb, "
+ "hugetlb_shared, shmem\n\n");
+ fprintf(stderr, "'Test mods' can be joined to the test type string with a ':'. "
+ "Supported mods:\n");
+ fprintf(stderr, "\tsyscall - Use userfaultfd(2) (default)\n");
+ fprintf(stderr, "\tdev - Use /dev/userfaultfd instead of userfaultfd(2)\n");
+ fprintf(stderr, "\tcollapse - Test MADV_COLLAPSE of UFFDIO_REGISTER_MODE_MINOR\n"
+ "memory\n");
+ fprintf(stderr, "\nExample test mod usage:\n");
+ fprintf(stderr, "# Run anonymous memory test with /dev/userfaultfd:\n");
+ fprintf(stderr, "./userfaultfd anon:dev 100 99999\n\n");
+
+ fprintf(stderr, "Examples:\n\n");
+ fprintf(stderr, "%s", examples);
+ exit(1);
+}
+
+#define _err(fmt, ...) \
+ do { \
+ int ret = errno; \
+ fprintf(stderr, "ERROR: " fmt, ##__VA_ARGS__); \
+ fprintf(stderr, " (errno=%d, line=%d)\n", \
+ ret, __LINE__); \
+ } while (0)
+
+#define errexit(exitcode, fmt, ...) \
+ do { \
+ _err(fmt, ##__VA_ARGS__); \
+ exit(exitcode); \
+ } while (0)
+
+#define err(fmt, ...) errexit(1, fmt, ##__VA_ARGS__)
+
+static void uffd_stats_reset(struct uffd_stats *uffd_stats,
+ unsigned long n_cpus)
+{
+ int i;
+
+ for (i = 0; i < n_cpus; i++) {
+ uffd_stats[i].cpu = i;
+ uffd_stats[i].missing_faults = 0;
+ uffd_stats[i].wp_faults = 0;
+ uffd_stats[i].minor_faults = 0;
+ }
+}
+
+static void uffd_stats_report(struct uffd_stats *stats, int n_cpus)
+{
+ int i;
+ unsigned long long miss_total = 0, wp_total = 0, minor_total = 0;
+
+ for (i = 0; i < n_cpus; i++) {
+ miss_total += stats[i].missing_faults;
+ wp_total += stats[i].wp_faults;
+ minor_total += stats[i].minor_faults;
+ }
+
+ printf("userfaults: ");
+ if (miss_total) {
+ printf("%llu missing (", miss_total);
+ for (i = 0; i < n_cpus; i++)
+ printf("%lu+", stats[i].missing_faults);
+ printf("\b) ");
+ }
+ if (wp_total) {
+ printf("%llu wp (", wp_total);
+ for (i = 0; i < n_cpus; i++)
+ printf("%lu+", stats[i].wp_faults);
+ printf("\b) ");
+ }
+ if (minor_total) {
+ printf("%llu minor (", minor_total);
+ for (i = 0; i < n_cpus; i++)
+ printf("%lu+", stats[i].minor_faults);
+ printf("\b)");
+ }
+ printf("\n");
+}
+
+static void anon_release_pages(char *rel_area)
+{
+ if (madvise(rel_area, nr_pages * page_size, MADV_DONTNEED))
+ err("madvise(MADV_DONTNEED) failed");
+}
+
+static void anon_allocate_area(void **alloc_area, bool is_src)
+{
+ *alloc_area = mmap(NULL, nr_pages * page_size, PROT_READ | PROT_WRITE,
+ MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+}
+
+static void noop_alias_mapping(__u64 *start, size_t len, unsigned long offset)
+{
+}
+
+static void hugetlb_release_pages(char *rel_area)
+{
+ if (!map_shared) {
+ if (madvise(rel_area, nr_pages * page_size, MADV_DONTNEED))
+ err("madvise(MADV_DONTNEED) failed");
+ } else {
+ if (madvise(rel_area, nr_pages * page_size, MADV_REMOVE))
+ err("madvise(MADV_REMOVE) failed");
+ }
+}
+
+static void hugetlb_allocate_area(void **alloc_area, bool is_src)
+{
+ off_t size = nr_pages * page_size;
+ off_t offset = is_src ? 0 : size;
+ void *area_alias = NULL;
+ char **alloc_area_alias;
+
+ *alloc_area = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ (map_shared ? MAP_SHARED : MAP_PRIVATE) |
+ (is_src ? 0 : MAP_NORESERVE),
+ mem_fd, offset);
+ if (*alloc_area == MAP_FAILED)
+ err("mmap of hugetlbfs file failed");
+
+ if (map_shared) {
+ area_alias = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ MAP_SHARED, mem_fd, offset);
+ if (area_alias == MAP_FAILED)
+ err("mmap of hugetlb file alias failed");
+ }
+
+ if (is_src) {
+ alloc_area_alias = &area_src_alias;
+ } else {
+ alloc_area_alias = &area_dst_alias;
+ }
+ if (area_alias)
+ *alloc_area_alias = area_alias;
+}
+
+static void hugetlb_alias_mapping(__u64 *start, size_t len, unsigned long offset)
+{
+ if (!map_shared)
+ return;
+
+ *start = (unsigned long) area_dst_alias + offset;
+}
+
+static void shmem_release_pages(char *rel_area)
+{
+ if (madvise(rel_area, nr_pages * page_size, MADV_REMOVE))
+ err("madvise(MADV_REMOVE) failed");
+}
+
+static void shmem_allocate_area(void **alloc_area, bool is_src)
+{
+ void *area_alias = NULL;
+ size_t bytes = nr_pages * page_size;
+ unsigned long offset = is_src ? 0 : bytes;
+ char *p = NULL, *p_alias = NULL;
+
+ if (test_collapse) {
+ p = BASE_PMD_ADDR;
+ if (!is_src)
+ /* src map + alias + interleaved hpages */
+ p += 2 * (bytes + hpage_size);
+ p_alias = p;
+ p_alias += bytes;
+ p_alias += hpage_size; /* Prevent src/dst VMA merge */
+ }
+
+ *alloc_area = mmap(p, bytes, PROT_READ | PROT_WRITE, MAP_SHARED,
+ mem_fd, offset);
+ if (*alloc_area == MAP_FAILED)
+ err("mmap of memfd failed");
+ if (test_collapse && *alloc_area != p)
+ err("mmap of memfd failed at %p", p);
+
+ area_alias = mmap(p_alias, bytes, PROT_READ | PROT_WRITE, MAP_SHARED,
+ mem_fd, offset);
+ if (area_alias == MAP_FAILED)
+ err("mmap of memfd alias failed");
+ if (test_collapse && area_alias != p_alias)
+ err("mmap of anonymous memory failed at %p", p_alias);
+
+ if (is_src)
+ area_src_alias = area_alias;
+ else
+ area_dst_alias = area_alias;
+}
+
+static void shmem_alias_mapping(__u64 *start, size_t len, unsigned long offset)
+{
+ *start = (unsigned long)area_dst_alias + offset;
+}
+
+static void shmem_check_pmd_mapping(void *p, int expect_nr_hpages)
+{
+ if (!check_huge_shmem(area_dst_alias, expect_nr_hpages, hpage_size))
+ err("Did not find expected %d number of hugepages",
+ expect_nr_hpages);
+}
+
+struct uffd_test_ops {
+ void (*allocate_area)(void **alloc_area, bool is_src);
+ void (*release_pages)(char *rel_area);
+ void (*alias_mapping)(__u64 *start, size_t len, unsigned long offset);
+ void (*check_pmd_mapping)(void *p, int expect_nr_hpages);
+};
+
+static struct uffd_test_ops anon_uffd_test_ops = {
+ .allocate_area = anon_allocate_area,
+ .release_pages = anon_release_pages,
+ .alias_mapping = noop_alias_mapping,
+ .check_pmd_mapping = NULL,
+};
+
+static struct uffd_test_ops shmem_uffd_test_ops = {
+ .allocate_area = shmem_allocate_area,
+ .release_pages = shmem_release_pages,
+ .alias_mapping = shmem_alias_mapping,
+ .check_pmd_mapping = shmem_check_pmd_mapping,
+};
+
+static struct uffd_test_ops hugetlb_uffd_test_ops = {
+ .allocate_area = hugetlb_allocate_area,
+ .release_pages = hugetlb_release_pages,
+ .alias_mapping = hugetlb_alias_mapping,
+ .check_pmd_mapping = NULL,
+};
+
+static struct uffd_test_ops *uffd_test_ops;
+
+static inline uint64_t uffd_minor_feature(void)
+{
+ if (test_type == TEST_HUGETLB && map_shared)
+ return UFFD_FEATURE_MINOR_HUGETLBFS;
+ else if (test_type == TEST_SHMEM)
+ return UFFD_FEATURE_MINOR_SHMEM;
+ else
+ return 0;
+}
+
+static uint64_t get_expected_ioctls(uint64_t mode)
+{
+ uint64_t ioctls = UFFD_API_RANGE_IOCTLS;
+
+ if (test_type == TEST_HUGETLB)
+ ioctls &= ~(1 << _UFFDIO_ZEROPAGE);
+
+ if (!((mode & UFFDIO_REGISTER_MODE_WP) && test_uffdio_wp))
+ ioctls &= ~(1 << _UFFDIO_WRITEPROTECT);
+
+ if (!((mode & UFFDIO_REGISTER_MODE_MINOR) && test_uffdio_minor))
+ ioctls &= ~(1 << _UFFDIO_CONTINUE);
+
+ return ioctls;
+}
+
+static void assert_expected_ioctls_present(uint64_t mode, uint64_t ioctls)
+{
+ uint64_t expected = get_expected_ioctls(mode);
+ uint64_t actual = ioctls & expected;
+
+ if (actual != expected) {
+ err("missing ioctl(s): expected %"PRIx64" actual: %"PRIx64,
+ expected, actual);
+ }
+}
+
+static int __userfaultfd_open_dev(void)
+{
+ int fd, _uffd;
+
+ fd = open("/dev/userfaultfd", O_RDWR | O_CLOEXEC);
+ if (fd < 0)
+ errexit(KSFT_SKIP, "opening /dev/userfaultfd failed");
+
+ _uffd = ioctl(fd, USERFAULTFD_IOC_NEW, UFFD_FLAGS);
+ if (_uffd < 0)
+ errexit(errno == ENOTTY ? KSFT_SKIP : 1,
+ "creating userfaultfd failed");
+ close(fd);
+ return _uffd;
+}
+
+static void userfaultfd_open(uint64_t *features)
+{
+ struct uffdio_api uffdio_api;
+
+ if (test_dev_userfaultfd)
+ uffd = __userfaultfd_open_dev();
+ else {
+ uffd = syscall(__NR_userfaultfd, UFFD_FLAGS);
+ if (uffd < 0)
+ errexit(errno == ENOSYS ? KSFT_SKIP : 1,
+ "creating userfaultfd failed");
+ }
+ uffd_flags = fcntl(uffd, F_GETFD, NULL);
+
+ uffdio_api.api = UFFD_API;
+ uffdio_api.features = *features;
+ if (ioctl(uffd, UFFDIO_API, &uffdio_api))
+ err("UFFDIO_API failed.\nPlease make sure to "
+ "run with either root or ptrace capability.");
+ if (uffdio_api.api != UFFD_API)
+ err("UFFDIO_API error: %" PRIu64, (uint64_t)uffdio_api.api);
+
+ *features = uffdio_api.features;
+}
+
+static inline void munmap_area(void **area)
+{
+ if (*area)
+ if (munmap(*area, nr_pages * page_size))
+ err("munmap");
+
+ *area = NULL;
+}
+
+static void uffd_test_ctx_clear(void)
+{
+ size_t i;
+
+ if (pipefd) {
+ for (i = 0; i < nr_cpus * 2; ++i) {
+ if (close(pipefd[i]))
+ err("close pipefd");
+ }
+ free(pipefd);
+ pipefd = NULL;
+ }
+
+ if (count_verify) {
+ free(count_verify);
+ count_verify = NULL;
+ }
+
+ if (uffd != -1) {
+ if (close(uffd))
+ err("close uffd");
+ uffd = -1;
+ }
+
+ munmap_area((void **)&area_src);
+ munmap_area((void **)&area_src_alias);
+ munmap_area((void **)&area_dst);
+ munmap_area((void **)&area_dst_alias);
+ munmap_area((void **)&area_remap);
+}
+
+static void uffd_test_ctx_init(uint64_t features)
+{
+ unsigned long nr, cpu;
+
+ uffd_test_ctx_clear();
+
+ uffd_test_ops->allocate_area((void **)&area_src, true);
+ uffd_test_ops->allocate_area((void **)&area_dst, false);
+
+ userfaultfd_open(&features);
+
+ count_verify = malloc(nr_pages * sizeof(unsigned long long));
+ if (!count_verify)
+ err("count_verify");
+
+ for (nr = 0; nr < nr_pages; nr++) {
+ *area_mutex(area_src, nr) =
+ (pthread_mutex_t)PTHREAD_MUTEX_INITIALIZER;
+ count_verify[nr] = *area_count(area_src, nr) = 1;
+ /*
+ * In the transition between 255 to 256, powerpc will
+ * read out of order in my_bcmp and see both bytes as
+ * zero, so leave a placeholder below always non-zero
+ * after the count, to avoid my_bcmp to trigger false
+ * positives.
+ */
+ *(area_count(area_src, nr) + 1) = 1;
+ }
+
+ /*
+ * After initialization of area_src, we must explicitly release pages
+ * for area_dst to make sure it's fully empty. Otherwise we could have
+ * some area_dst pages be errornously initialized with zero pages,
+ * hence we could hit memory corruption later in the test.
+ *
+ * One example is when THP is globally enabled, above allocate_area()
+ * calls could have the two areas merged into a single VMA (as they
+ * will have the same VMA flags so they're mergeable). When we
+ * initialize the area_src above, it's possible that some part of
+ * area_dst could have been faulted in via one huge THP that will be
+ * shared between area_src and area_dst. It could cause some of the
+ * area_dst won't be trapped by missing userfaults.
+ *
+ * This release_pages() will guarantee even if that happened, we'll
+ * proactively split the thp and drop any accidentally initialized
+ * pages within area_dst.
+ */
+ uffd_test_ops->release_pages(area_dst);
+
+ pipefd = malloc(sizeof(int) * nr_cpus * 2);
+ if (!pipefd)
+ err("pipefd");
+ for (cpu = 0; cpu < nr_cpus; cpu++)
+ if (pipe2(&pipefd[cpu * 2], O_CLOEXEC | O_NONBLOCK))
+ err("pipe");
+}
+
+static int my_bcmp(char *str1, char *str2, size_t n)
+{
+ unsigned long i;
+ for (i = 0; i < n; i++)
+ if (str1[i] != str2[i])
+ return 1;
+ return 0;
+}
+
+static void wp_range(int ufd, __u64 start, __u64 len, bool wp)
+{
+ struct uffdio_writeprotect prms;
+
+ /* Write protection page faults */
+ prms.range.start = start;
+ prms.range.len = len;
+ /* Undo write-protect, do wakeup after that */
+ prms.mode = wp ? UFFDIO_WRITEPROTECT_MODE_WP : 0;
+
+ if (ioctl(ufd, UFFDIO_WRITEPROTECT, &prms))
+ err("clear WP failed: address=0x%"PRIx64, (uint64_t)start);
+}
+
+static void continue_range(int ufd, __u64 start, __u64 len)
+{
+ struct uffdio_continue req;
+ int ret;
+
+ req.range.start = start;
+ req.range.len = len;
+ req.mode = 0;
+
+ if (ioctl(ufd, UFFDIO_CONTINUE, &req))
+ err("UFFDIO_CONTINUE failed for address 0x%" PRIx64,
+ (uint64_t)start);
+
+ /*
+ * Error handling within the kernel for continue is subtly different
+ * from copy or zeropage, so it may be a source of bugs. Trigger an
+ * error (-EEXIST) on purpose, to verify doing so doesn't cause a BUG.
+ */
+ req.mapped = 0;
+ ret = ioctl(ufd, UFFDIO_CONTINUE, &req);
+ if (ret >= 0 || req.mapped != -EEXIST)
+ err("failed to exercise UFFDIO_CONTINUE error handling, ret=%d, mapped=%" PRId64,
+ ret, (int64_t) req.mapped);
+}
+
+static void *locking_thread(void *arg)
+{
+ unsigned long cpu = (unsigned long) arg;
+ unsigned long page_nr;
+ unsigned long long count;
+
+ if (!(bounces & BOUNCE_RANDOM)) {
+ page_nr = -bounces;
+ if (!(bounces & BOUNCE_RACINGFAULTS))
+ page_nr += cpu * nr_pages_per_cpu;
+ }
+
+ while (!finished) {
+ if (bounces & BOUNCE_RANDOM) {
+ if (getrandom(&page_nr, sizeof(page_nr), 0) != sizeof(page_nr))
+ err("getrandom failed");
+ } else
+ page_nr += 1;
+ page_nr %= nr_pages;
+ pthread_mutex_lock(area_mutex(area_dst, page_nr));
+ count = *area_count(area_dst, page_nr);
+ if (count != count_verify[page_nr])
+ err("page_nr %lu memory corruption %llu %llu",
+ page_nr, count, count_verify[page_nr]);
+ count++;
+ *area_count(area_dst, page_nr) = count_verify[page_nr] = count;
+ pthread_mutex_unlock(area_mutex(area_dst, page_nr));
+ }
+
+ return NULL;
+}
+
+static void retry_copy_page(int ufd, struct uffdio_copy *uffdio_copy,
+ unsigned long offset)
+{
+ uffd_test_ops->alias_mapping(&uffdio_copy->dst,
+ uffdio_copy->len,
+ offset);
+ if (ioctl(ufd, UFFDIO_COPY, uffdio_copy)) {
+ /* real retval in ufdio_copy.copy */
+ if (uffdio_copy->copy != -EEXIST)
+ err("UFFDIO_COPY retry error: %"PRId64,
+ (int64_t)uffdio_copy->copy);
+ } else {
+ err("UFFDIO_COPY retry unexpected: %"PRId64,
+ (int64_t)uffdio_copy->copy);
+ }
+}
+
+static void wake_range(int ufd, unsigned long addr, unsigned long len)
+{
+ struct uffdio_range uffdio_wake;
+
+ uffdio_wake.start = addr;
+ uffdio_wake.len = len;
+
+ if (ioctl(ufd, UFFDIO_WAKE, &uffdio_wake))
+ fprintf(stderr, "error waking %lu\n",
+ addr), exit(1);
+}
+
+static int __copy_page(int ufd, unsigned long offset, bool retry)
+{
+ struct uffdio_copy uffdio_copy;
+
+ if (offset >= nr_pages * page_size)
+ err("unexpected offset %lu\n", offset);
+ uffdio_copy.dst = (unsigned long) area_dst + offset;
+ uffdio_copy.src = (unsigned long) area_src + offset;
+ uffdio_copy.len = page_size;
+ if (test_uffdio_wp)
+ uffdio_copy.mode = UFFDIO_COPY_MODE_WP;
+ else
+ uffdio_copy.mode = 0;
+ uffdio_copy.copy = 0;
+ if (ioctl(ufd, UFFDIO_COPY, &uffdio_copy)) {
+ /* real retval in ufdio_copy.copy */
+ if (uffdio_copy.copy != -EEXIST)
+ err("UFFDIO_COPY error: %"PRId64,
+ (int64_t)uffdio_copy.copy);
+ wake_range(ufd, uffdio_copy.dst, page_size);
+ } else if (uffdio_copy.copy != page_size) {
+ err("UFFDIO_COPY error: %"PRId64, (int64_t)uffdio_copy.copy);
+ } else {
+ if (test_uffdio_copy_eexist && retry) {
+ test_uffdio_copy_eexist = false;
+ retry_copy_page(ufd, &uffdio_copy, offset);
+ }
+ return 1;
+ }
+ return 0;
+}
+
+static int copy_page_retry(int ufd, unsigned long offset)
+{
+ return __copy_page(ufd, offset, true);
+}
+
+static int copy_page(int ufd, unsigned long offset)
+{
+ return __copy_page(ufd, offset, false);
+}
+
+static int uffd_read_msg(int ufd, struct uffd_msg *msg)
+{
+ int ret = read(uffd, msg, sizeof(*msg));
+
+ if (ret != sizeof(*msg)) {
+ if (ret < 0) {
+ if (errno == EAGAIN || errno == EINTR)
+ return 1;
+ err("blocking read error");
+ } else {
+ err("short read");
+ }
+ }
+
+ return 0;
+}
+
+static void uffd_handle_page_fault(struct uffd_msg *msg,
+ struct uffd_stats *stats)
+{
+ unsigned long offset;
+
+ if (msg->event != UFFD_EVENT_PAGEFAULT)
+ err("unexpected msg event %u", msg->event);
+
+ if (msg->arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WP) {
+ /* Write protect page faults */
+ wp_range(uffd, msg->arg.pagefault.address, page_size, false);
+ stats->wp_faults++;
+ } else if (msg->arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_MINOR) {
+ uint8_t *area;
+ int b;
+
+ /*
+ * Minor page faults
+ *
+ * To prove we can modify the original range for testing
+ * purposes, we're going to bit flip this range before
+ * continuing.
+ *
+ * Note that this requires all minor page fault tests operate on
+ * area_dst (non-UFFD-registered) and area_dst_alias
+ * (UFFD-registered).
+ */
+
+ area = (uint8_t *)(area_dst +
+ ((char *)msg->arg.pagefault.address -
+ area_dst_alias));
+ for (b = 0; b < page_size; ++b)
+ area[b] = ~area[b];
+ continue_range(uffd, msg->arg.pagefault.address, page_size);
+ stats->minor_faults++;
+ } else {
+ /*
+ * Missing page faults.
+ *
+ * Here we force a write check for each of the missing mode
+ * faults. It's guaranteed because the only threads that
+ * will trigger uffd faults are the locking threads, and
+ * their first instruction to touch the missing page will
+ * always be pthread_mutex_lock().
+ *
+ * Note that here we relied on an NPTL glibc impl detail to
+ * always read the lock type at the entry of the lock op
+ * (pthread_mutex_t.__data.__type, offset 0x10) before
+ * doing any locking operations to guarantee that. It's
+ * actually not good to rely on this impl detail because
+ * logically a pthread-compatible lib can implement the
+ * locks without types and we can fail when linking with
+ * them. However since we used to find bugs with this
+ * strict check we still keep it around. Hopefully this
+ * could be a good hint when it fails again. If one day
+ * it'll break on some other impl of glibc we'll revisit.
+ */
+ if (msg->arg.pagefault.flags & UFFD_PAGEFAULT_FLAG_WRITE)
+ err("unexpected write fault");
+
+ offset = (char *)(unsigned long)msg->arg.pagefault.address - area_dst;
+ offset &= ~(page_size-1);
+
+ if (copy_page(uffd, offset))
+ stats->missing_faults++;
+ }
+}
+
+static void *uffd_poll_thread(void *arg)
+{
+ struct uffd_stats *stats = (struct uffd_stats *)arg;
+ unsigned long cpu = stats->cpu;
+ struct pollfd pollfd[2];
+ struct uffd_msg msg;
+ struct uffdio_register uffd_reg;
+ int ret;
+ char tmp_chr;
+
+ pollfd[0].fd = uffd;
+ pollfd[0].events = POLLIN;
+ pollfd[1].fd = pipefd[cpu*2];
+ pollfd[1].events = POLLIN;
+
+ for (;;) {
+ ret = poll(pollfd, 2, -1);
+ if (ret <= 0) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ err("poll error: %d", ret);
+ }
+ if (pollfd[1].revents & POLLIN) {
+ if (read(pollfd[1].fd, &tmp_chr, 1) != 1)
+ err("read pipefd error");
+ break;
+ }
+ if (!(pollfd[0].revents & POLLIN))
+ err("pollfd[0].revents %d", pollfd[0].revents);
+ if (uffd_read_msg(uffd, &msg))
+ continue;
+ switch (msg.event) {
+ default:
+ err("unexpected msg event %u\n", msg.event);
+ break;
+ case UFFD_EVENT_PAGEFAULT:
+ uffd_handle_page_fault(&msg, stats);
+ break;
+ case UFFD_EVENT_FORK:
+ close(uffd);
+ uffd = msg.arg.fork.ufd;
+ pollfd[0].fd = uffd;
+ break;
+ case UFFD_EVENT_REMOVE:
+ uffd_reg.range.start = msg.arg.remove.start;
+ uffd_reg.range.len = msg.arg.remove.end -
+ msg.arg.remove.start;
+ if (ioctl(uffd, UFFDIO_UNREGISTER, &uffd_reg.range))
+ err("remove failure");
+ break;
+ case UFFD_EVENT_REMAP:
+ area_remap = area_dst; /* save for later unmap */
+ area_dst = (char *)(unsigned long)msg.arg.remap.to;
+ break;
+ }
+ }
+
+ return NULL;
+}
+
+pthread_mutex_t uffd_read_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static void *uffd_read_thread(void *arg)
+{
+ struct uffd_stats *stats = (struct uffd_stats *)arg;
+ struct uffd_msg msg;
+
+ pthread_mutex_unlock(&uffd_read_mutex);
+ /* from here cancellation is ok */
+
+ for (;;) {
+ if (uffd_read_msg(uffd, &msg))
+ continue;
+ uffd_handle_page_fault(&msg, stats);
+ }
+
+ return NULL;
+}
+
+static void *background_thread(void *arg)
+{
+ unsigned long cpu = (unsigned long) arg;
+ unsigned long page_nr, start_nr, mid_nr, end_nr;
+
+ start_nr = cpu * nr_pages_per_cpu;
+ end_nr = (cpu+1) * nr_pages_per_cpu;
+ mid_nr = (start_nr + end_nr) / 2;
+
+ /* Copy the first half of the pages */
+ for (page_nr = start_nr; page_nr < mid_nr; page_nr++)
+ copy_page_retry(uffd, page_nr * page_size);
+
+ /*
+ * If we need to test uffd-wp, set it up now. Then we'll have
+ * at least the first half of the pages mapped already which
+ * can be write-protected for testing
+ */
+ if (test_uffdio_wp)
+ wp_range(uffd, (unsigned long)area_dst + start_nr * page_size,
+ nr_pages_per_cpu * page_size, true);
+
+ /*
+ * Continue the 2nd half of the page copying, handling write
+ * protection faults if any
+ */
+ for (page_nr = mid_nr; page_nr < end_nr; page_nr++)
+ copy_page_retry(uffd, page_nr * page_size);
+
+ return NULL;
+}
+
+static int stress(struct uffd_stats *uffd_stats)
+{
+ unsigned long cpu;
+ pthread_t locking_threads[nr_cpus];
+ pthread_t uffd_threads[nr_cpus];
+ pthread_t background_threads[nr_cpus];
+
+ finished = 0;
+ for (cpu = 0; cpu < nr_cpus; cpu++) {
+ if (pthread_create(&locking_threads[cpu], &attr,
+ locking_thread, (void *)cpu))
+ return 1;
+ if (bounces & BOUNCE_POLL) {
+ if (pthread_create(&uffd_threads[cpu], &attr,
+ uffd_poll_thread,
+ (void *)&uffd_stats[cpu]))
+ return 1;
+ } else {
+ if (pthread_create(&uffd_threads[cpu], &attr,
+ uffd_read_thread,
+ (void *)&uffd_stats[cpu]))
+ return 1;
+ pthread_mutex_lock(&uffd_read_mutex);
+ }
+ if (pthread_create(&background_threads[cpu], &attr,
+ background_thread, (void *)cpu))
+ return 1;
+ }
+ for (cpu = 0; cpu < nr_cpus; cpu++)
+ if (pthread_join(background_threads[cpu], NULL))
+ return 1;
+
+ /*
+ * Be strict and immediately zap area_src, the whole area has
+ * been transferred already by the background treads. The
+ * area_src could then be faulted in a racy way by still
+ * running uffdio_threads reading zeropages after we zapped
+ * area_src (but they're guaranteed to get -EEXIST from
+ * UFFDIO_COPY without writing zero pages into area_dst
+ * because the background threads already completed).
+ */
+ uffd_test_ops->release_pages(area_src);
+
+ finished = 1;
+ for (cpu = 0; cpu < nr_cpus; cpu++)
+ if (pthread_join(locking_threads[cpu], NULL))
+ return 1;
+
+ for (cpu = 0; cpu < nr_cpus; cpu++) {
+ char c;
+ if (bounces & BOUNCE_POLL) {
+ if (write(pipefd[cpu*2+1], &c, 1) != 1)
+ err("pipefd write error");
+ if (pthread_join(uffd_threads[cpu],
+ (void *)&uffd_stats[cpu]))
+ return 1;
+ } else {
+ if (pthread_cancel(uffd_threads[cpu]))
+ return 1;
+ if (pthread_join(uffd_threads[cpu], NULL))
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+sigjmp_buf jbuf, *sigbuf;
+
+static void sighndl(int sig, siginfo_t *siginfo, void *ptr)
+{
+ if (sig == SIGBUS) {
+ if (sigbuf)
+ siglongjmp(*sigbuf, 1);
+ abort();
+ }
+}
+
+/*
+ * For non-cooperative userfaultfd test we fork() a process that will
+ * generate pagefaults, will mremap the area monitored by the
+ * userfaultfd and at last this process will release the monitored
+ * area.
+ * For the anonymous and shared memory the area is divided into two
+ * parts, the first part is accessed before mremap, and the second
+ * part is accessed after mremap. Since hugetlbfs does not support
+ * mremap, the entire monitored area is accessed in a single pass for
+ * HUGETLB_TEST.
+ * The release of the pages currently generates event for shmem and
+ * anonymous memory (UFFD_EVENT_REMOVE), hence it is not checked
+ * for hugetlb.
+ * For signal test(UFFD_FEATURE_SIGBUS), signal_test = 1, we register
+ * monitored area, generate pagefaults and test that signal is delivered.
+ * Use UFFDIO_COPY to allocate missing page and retry. For signal_test = 2
+ * test robustness use case - we release monitored area, fork a process
+ * that will generate pagefaults and verify signal is generated.
+ * This also tests UFFD_FEATURE_EVENT_FORK event along with the signal
+ * feature. Using monitor thread, verify no userfault events are generated.
+ */
+static int faulting_process(int signal_test)
+{
+ unsigned long nr;
+ unsigned long long count;
+ unsigned long split_nr_pages;
+ unsigned long lastnr;
+ struct sigaction act;
+ volatile unsigned long signalled = 0;
+
+ split_nr_pages = (nr_pages + 1) / 2;
+
+ if (signal_test) {
+ sigbuf = &jbuf;
+ memset(&act, 0, sizeof(act));
+ act.sa_sigaction = sighndl;
+ act.sa_flags = SA_SIGINFO;
+ if (sigaction(SIGBUS, &act, 0))
+ err("sigaction");
+ lastnr = (unsigned long)-1;
+ }
+
+ for (nr = 0; nr < split_nr_pages; nr++) {
+ volatile int steps = 1;
+ unsigned long offset = nr * page_size;
+
+ if (signal_test) {
+ if (sigsetjmp(*sigbuf, 1) != 0) {
+ if (steps == 1 && nr == lastnr)
+ err("Signal repeated");
+
+ lastnr = nr;
+ if (signal_test == 1) {
+ if (steps == 1) {
+ /* This is a MISSING request */
+ steps++;
+ if (copy_page(uffd, offset))
+ signalled++;
+ } else {
+ /* This is a WP request */
+ assert(steps == 2);
+ wp_range(uffd,
+ (__u64)area_dst +
+ offset,
+ page_size, false);
+ }
+ } else {
+ signalled++;
+ continue;
+ }
+ }
+ }
+
+ count = *area_count(area_dst, nr);
+ if (count != count_verify[nr])
+ err("nr %lu memory corruption %llu %llu\n",
+ nr, count, count_verify[nr]);
+ /*
+ * Trigger write protection if there is by writing
+ * the same value back.
+ */
+ *area_count(area_dst, nr) = count;
+ }
+
+ if (signal_test)
+ return signalled != split_nr_pages;
+
+ area_dst = mremap(area_dst, nr_pages * page_size, nr_pages * page_size,
+ MREMAP_MAYMOVE | MREMAP_FIXED, area_src);
+ if (area_dst == MAP_FAILED)
+ err("mremap");
+ /* Reset area_src since we just clobbered it */
+ area_src = NULL;
+
+ for (; nr < nr_pages; nr++) {
+ count = *area_count(area_dst, nr);
+ if (count != count_verify[nr]) {
+ err("nr %lu memory corruption %llu %llu\n",
+ nr, count, count_verify[nr]);
+ }
+ /*
+ * Trigger write protection if there is by writing
+ * the same value back.
+ */
+ *area_count(area_dst, nr) = count;
+ }
+
+ uffd_test_ops->release_pages(area_dst);
+
+ for (nr = 0; nr < nr_pages; nr++)
+ if (my_bcmp(area_dst + nr * page_size, zeropage, page_size))
+ err("nr %lu is not zero", nr);
+
+ return 0;
+}
+
+static void retry_uffdio_zeropage(int ufd,
+ struct uffdio_zeropage *uffdio_zeropage,
+ unsigned long offset)
+{
+ uffd_test_ops->alias_mapping(&uffdio_zeropage->range.start,
+ uffdio_zeropage->range.len,
+ offset);
+ if (ioctl(ufd, UFFDIO_ZEROPAGE, uffdio_zeropage)) {
+ if (uffdio_zeropage->zeropage != -EEXIST)
+ err("UFFDIO_ZEROPAGE error: %"PRId64,
+ (int64_t)uffdio_zeropage->zeropage);
+ } else {
+ err("UFFDIO_ZEROPAGE error: %"PRId64,
+ (int64_t)uffdio_zeropage->zeropage);
+ }
+}
+
+static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry)
+{
+ struct uffdio_zeropage uffdio_zeropage;
+ int ret;
+ bool has_zeropage = get_expected_ioctls(0) & (1 << _UFFDIO_ZEROPAGE);
+ __s64 res;
+
+ if (offset >= nr_pages * page_size)
+ err("unexpected offset %lu", offset);
+ uffdio_zeropage.range.start = (unsigned long) area_dst + offset;
+ uffdio_zeropage.range.len = page_size;
+ uffdio_zeropage.mode = 0;
+ ret = ioctl(ufd, UFFDIO_ZEROPAGE, &uffdio_zeropage);
+ res = uffdio_zeropage.zeropage;
+ if (ret) {
+ /* real retval in ufdio_zeropage.zeropage */
+ if (has_zeropage)
+ err("UFFDIO_ZEROPAGE error: %"PRId64, (int64_t)res);
+ else if (res != -EINVAL)
+ err("UFFDIO_ZEROPAGE not -EINVAL");
+ } else if (has_zeropage) {
+ if (res != page_size) {
+ err("UFFDIO_ZEROPAGE unexpected size");
+ } else {
+ if (test_uffdio_zeropage_eexist && retry) {
+ test_uffdio_zeropage_eexist = false;
+ retry_uffdio_zeropage(ufd, &uffdio_zeropage,
+ offset);
+ }
+ return 1;
+ }
+ } else
+ err("UFFDIO_ZEROPAGE succeeded");
+
+ return 0;
+}
+
+static int uffdio_zeropage(int ufd, unsigned long offset)
+{
+ return __uffdio_zeropage(ufd, offset, false);
+}
+
+/* exercise UFFDIO_ZEROPAGE */
+static int userfaultfd_zeropage_test(void)
+{
+ struct uffdio_register uffdio_register;
+
+ printf("testing UFFDIO_ZEROPAGE: ");
+ fflush(stdout);
+
+ uffd_test_ctx_init(0);
+
+ uffdio_register.range.start = (unsigned long) area_dst;
+ uffdio_register.range.len = nr_pages * page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
+ if (test_uffdio_wp)
+ uffdio_register.mode |= UFFDIO_REGISTER_MODE_WP;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ err("register failure");
+
+ assert_expected_ioctls_present(
+ uffdio_register.mode, uffdio_register.ioctls);
+
+ if (uffdio_zeropage(uffd, 0))
+ if (my_bcmp(area_dst, zeropage, page_size))
+ err("zeropage is not zero");
+
+ printf("done.\n");
+ return 0;
+}
+
+static int userfaultfd_events_test(void)
+{
+ struct uffdio_register uffdio_register;
+ pthread_t uffd_mon;
+ int err, features;
+ pid_t pid;
+ char c;
+ struct uffd_stats stats = { 0 };
+
+ printf("testing events (fork, remap, remove): ");
+ fflush(stdout);
+
+ features = UFFD_FEATURE_EVENT_FORK | UFFD_FEATURE_EVENT_REMAP |
+ UFFD_FEATURE_EVENT_REMOVE;
+ uffd_test_ctx_init(features);
+
+ fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+
+ uffdio_register.range.start = (unsigned long) area_dst;
+ uffdio_register.range.len = nr_pages * page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
+ if (test_uffdio_wp)
+ uffdio_register.mode |= UFFDIO_REGISTER_MODE_WP;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ err("register failure");
+
+ assert_expected_ioctls_present(
+ uffdio_register.mode, uffdio_register.ioctls);
+
+ if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &stats))
+ err("uffd_poll_thread create");
+
+ pid = fork();
+ if (pid < 0)
+ err("fork");
+
+ if (!pid)
+ exit(faulting_process(0));
+
+ waitpid(pid, &err, 0);
+ if (err)
+ err("faulting process failed");
+ if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+ err("pipe write");
+ if (pthread_join(uffd_mon, NULL))
+ return 1;
+
+ uffd_stats_report(&stats, 1);
+
+ return stats.missing_faults != nr_pages;
+}
+
+static int userfaultfd_sig_test(void)
+{
+ struct uffdio_register uffdio_register;
+ unsigned long userfaults;
+ pthread_t uffd_mon;
+ int err, features;
+ pid_t pid;
+ char c;
+ struct uffd_stats stats = { 0 };
+
+ printf("testing signal delivery: ");
+ fflush(stdout);
+
+ features = UFFD_FEATURE_EVENT_FORK|UFFD_FEATURE_SIGBUS;
+ uffd_test_ctx_init(features);
+
+ fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+
+ uffdio_register.range.start = (unsigned long) area_dst;
+ uffdio_register.range.len = nr_pages * page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
+ if (test_uffdio_wp)
+ uffdio_register.mode |= UFFDIO_REGISTER_MODE_WP;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ err("register failure");
+
+ assert_expected_ioctls_present(
+ uffdio_register.mode, uffdio_register.ioctls);
+
+ if (faulting_process(1))
+ err("faulting process failed");
+
+ uffd_test_ops->release_pages(area_dst);
+
+ if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &stats))
+ err("uffd_poll_thread create");
+
+ pid = fork();
+ if (pid < 0)
+ err("fork");
+
+ if (!pid)
+ exit(faulting_process(2));
+
+ waitpid(pid, &err, 0);
+ if (err)
+ err("faulting process failed");
+ if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+ err("pipe write");
+ if (pthread_join(uffd_mon, (void **)&userfaults))
+ return 1;
+
+ printf("done.\n");
+ if (userfaults)
+ err("Signal test failed, userfaults: %ld", userfaults);
+
+ return userfaults != 0;
+}
+
+void check_memory_contents(char *p)
+{
+ unsigned long i;
+ uint8_t expected_byte;
+ void *expected_page;
+
+ if (posix_memalign(&expected_page, page_size, page_size))
+ err("out of memory");
+
+ for (i = 0; i < nr_pages; ++i) {
+ expected_byte = ~((uint8_t)(i % ((uint8_t)-1)));
+ memset(expected_page, expected_byte, page_size);
+ if (my_bcmp(expected_page, p + (i * page_size), page_size))
+ err("unexpected page contents after minor fault");
+ }
+
+ free(expected_page);
+}
+
+static int userfaultfd_minor_test(void)
+{
+ unsigned long p;
+ struct uffdio_register uffdio_register;
+ pthread_t uffd_mon;
+ char c;
+ struct uffd_stats stats = { 0 };
+
+ if (!test_uffdio_minor)
+ return 0;
+
+ printf("testing minor faults: ");
+ fflush(stdout);
+
+ uffd_test_ctx_init(uffd_minor_feature());
+
+ uffdio_register.range.start = (unsigned long)area_dst_alias;
+ uffdio_register.range.len = nr_pages * page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MINOR;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ err("register failure");
+
+ assert_expected_ioctls_present(
+ uffdio_register.mode, uffdio_register.ioctls);
+
+ /*
+ * After registering with UFFD, populate the non-UFFD-registered side of
+ * the shared mapping. This should *not* trigger any UFFD minor faults.
+ */
+ for (p = 0; p < nr_pages; ++p) {
+ memset(area_dst + (p * page_size), p % ((uint8_t)-1),
+ page_size);
+ }
+
+ if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &stats))
+ err("uffd_poll_thread create");
+
+ /*
+ * Read each of the pages back using the UFFD-registered mapping. We
+ * expect that the first time we touch a page, it will result in a minor
+ * fault. uffd_poll_thread will resolve the fault by bit-flipping the
+ * page's contents, and then issuing a CONTINUE ioctl.
+ */
+ check_memory_contents(area_dst_alias);
+
+ if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+ err("pipe write");
+ if (pthread_join(uffd_mon, NULL))
+ return 1;
+
+ uffd_stats_report(&stats, 1);
+
+ if (test_collapse) {
+ printf("testing collapse of uffd memory into PMD-mapped THPs:");
+ if (madvise(area_dst_alias, nr_pages * page_size,
+ MADV_COLLAPSE))
+ err("madvise(MADV_COLLAPSE)");
+
+ uffd_test_ops->check_pmd_mapping(area_dst,
+ nr_pages * page_size /
+ hpage_size);
+ /*
+ * This won't cause uffd-fault - it purely just makes sure there
+ * was no corruption.
+ */
+ check_memory_contents(area_dst_alias);
+ printf(" done.\n");
+ }
+
+ return stats.missing_faults != 0 || stats.minor_faults != nr_pages;
+}
+
+#define BIT_ULL(nr) (1ULL << (nr))
+#define PM_SOFT_DIRTY BIT_ULL(55)
+#define PM_MMAP_EXCLUSIVE BIT_ULL(56)
+#define PM_UFFD_WP BIT_ULL(57)
+#define PM_FILE BIT_ULL(61)
+#define PM_SWAP BIT_ULL(62)
+#define PM_PRESENT BIT_ULL(63)
+
+static int pagemap_open(void)
+{
+ int fd = open("/proc/self/pagemap", O_RDONLY);
+
+ if (fd < 0)
+ err("open pagemap");
+
+ return fd;
+}
+
+static uint64_t pagemap_read_vaddr(int fd, void *vaddr)
+{
+ uint64_t value;
+ int ret;
+
+ ret = pread(fd, &value, sizeof(uint64_t),
+ ((uint64_t)vaddr >> 12) * sizeof(uint64_t));
+ if (ret != sizeof(uint64_t))
+ err("pread() on pagemap failed");
+
+ return value;
+}
+
+/* This macro let __LINE__ works in err() */
+#define pagemap_check_wp(value, wp) do { \
+ if (!!(value & PM_UFFD_WP) != wp) \
+ err("pagemap uffd-wp bit error: 0x%"PRIx64, value); \
+ } while (0)
+
+static int pagemap_test_fork(bool present)
+{
+ pid_t child = fork();
+ uint64_t value;
+ int fd, result;
+
+ if (!child) {
+ /* Open the pagemap fd of the child itself */
+ fd = pagemap_open();
+ value = pagemap_read_vaddr(fd, area_dst);
+ /*
+ * After fork() uffd-wp bit should be gone as long as we're
+ * without UFFD_FEATURE_EVENT_FORK
+ */
+ pagemap_check_wp(value, false);
+ /* Succeed */
+ exit(0);
+ }
+ waitpid(child, &result, 0);
+ return result;
+}
+
+static void userfaultfd_pagemap_test(unsigned int test_pgsize)
+{
+ struct uffdio_register uffdio_register;
+ int pagemap_fd;
+ uint64_t value;
+
+ /* Pagemap tests uffd-wp only */
+ if (!test_uffdio_wp)
+ return;
+
+ /* Not enough memory to test this page size */
+ if (test_pgsize > nr_pages * page_size)
+ return;
+
+ printf("testing uffd-wp with pagemap (pgsize=%u): ", test_pgsize);
+ /* Flush so it doesn't flush twice in parent/child later */
+ fflush(stdout);
+
+ uffd_test_ctx_init(0);
+
+ if (test_pgsize > page_size) {
+ /* This is a thp test */
+ if (madvise(area_dst, nr_pages * page_size, MADV_HUGEPAGE))
+ err("madvise(MADV_HUGEPAGE) failed");
+ } else if (test_pgsize == page_size) {
+ /* This is normal page test; force no thp */
+ if (madvise(area_dst, nr_pages * page_size, MADV_NOHUGEPAGE))
+ err("madvise(MADV_NOHUGEPAGE) failed");
+ }
+
+ uffdio_register.range.start = (unsigned long) area_dst;
+ uffdio_register.range.len = nr_pages * page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_WP;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ err("register failed");
+
+ pagemap_fd = pagemap_open();
+
+ /* Touch the page */
+ *area_dst = 1;
+ wp_range(uffd, (uint64_t)area_dst, test_pgsize, true);
+ value = pagemap_read_vaddr(pagemap_fd, area_dst);
+ pagemap_check_wp(value, true);
+ /* Make sure uffd-wp bit dropped when fork */
+ if (pagemap_test_fork(true))
+ err("Detected stall uffd-wp bit in child");
+
+ /* Exclusive required or PAGEOUT won't work */
+ if (!(value & PM_MMAP_EXCLUSIVE))
+ err("multiple mapping detected: 0x%"PRIx64, value);
+
+ if (madvise(area_dst, test_pgsize, MADV_PAGEOUT))
+ err("madvise(MADV_PAGEOUT) failed");
+
+ /* Uffd-wp should persist even swapped out */
+ value = pagemap_read_vaddr(pagemap_fd, area_dst);
+ pagemap_check_wp(value, true);
+ /* Make sure uffd-wp bit dropped when fork */
+ if (pagemap_test_fork(false))
+ err("Detected stall uffd-wp bit in child");
+
+ /* Unprotect; this tests swap pte modifications */
+ wp_range(uffd, (uint64_t)area_dst, page_size, false);
+ value = pagemap_read_vaddr(pagemap_fd, area_dst);
+ pagemap_check_wp(value, false);
+
+ /* Fault in the page from disk */
+ *area_dst = 2;
+ value = pagemap_read_vaddr(pagemap_fd, area_dst);
+ pagemap_check_wp(value, false);
+
+ close(pagemap_fd);
+ printf("done\n");
+}
+
+static int userfaultfd_stress(void)
+{
+ void *area;
+ unsigned long nr;
+ struct uffdio_register uffdio_register;
+ struct uffd_stats uffd_stats[nr_cpus];
+
+ uffd_test_ctx_init(0);
+
+ if (posix_memalign(&area, page_size, page_size))
+ err("out of memory");
+ zeropage = area;
+ bzero(zeropage, page_size);
+
+ pthread_mutex_lock(&uffd_read_mutex);
+
+ pthread_attr_init(&attr);
+ pthread_attr_setstacksize(&attr, 16*1024*1024);
+
+ while (bounces--) {
+ printf("bounces: %d, mode:", bounces);
+ if (bounces & BOUNCE_RANDOM)
+ printf(" rnd");
+ if (bounces & BOUNCE_RACINGFAULTS)
+ printf(" racing");
+ if (bounces & BOUNCE_VERIFY)
+ printf(" ver");
+ if (bounces & BOUNCE_POLL)
+ printf(" poll");
+ else
+ printf(" read");
+ printf(", ");
+ fflush(stdout);
+
+ if (bounces & BOUNCE_POLL)
+ fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+ else
+ fcntl(uffd, F_SETFL, uffd_flags & ~O_NONBLOCK);
+
+ /* register */
+ uffdio_register.range.start = (unsigned long) area_dst;
+ uffdio_register.range.len = nr_pages * page_size;
+ uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
+ if (test_uffdio_wp)
+ uffdio_register.mode |= UFFDIO_REGISTER_MODE_WP;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ err("register failure");
+ assert_expected_ioctls_present(
+ uffdio_register.mode, uffdio_register.ioctls);
+
+ if (area_dst_alias) {
+ uffdio_register.range.start = (unsigned long)
+ area_dst_alias;
+ if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+ err("register failure alias");
+ }
+
+ /*
+ * The madvise done previously isn't enough: some
+ * uffd_thread could have read userfaults (one of
+ * those already resolved by the background thread)
+ * and it may be in the process of calling
+ * UFFDIO_COPY. UFFDIO_COPY will read the zapped
+ * area_src and it would map a zero page in it (of
+ * course such a UFFDIO_COPY is perfectly safe as it'd
+ * return -EEXIST). The problem comes at the next
+ * bounce though: that racing UFFDIO_COPY would
+ * generate zeropages in the area_src, so invalidating
+ * the previous MADV_DONTNEED. Without this additional
+ * MADV_DONTNEED those zeropages leftovers in the
+ * area_src would lead to -EEXIST failure during the
+ * next bounce, effectively leaving a zeropage in the
+ * area_dst.
+ *
+ * Try to comment this out madvise to see the memory
+ * corruption being caught pretty quick.
+ *
+ * khugepaged is also inhibited to collapse THP after
+ * MADV_DONTNEED only after the UFFDIO_REGISTER, so it's
+ * required to MADV_DONTNEED here.
+ */
+ uffd_test_ops->release_pages(area_dst);
+
+ uffd_stats_reset(uffd_stats, nr_cpus);
+
+ /* bounce pass */
+ if (stress(uffd_stats))
+ return 1;
+
+ /* Clear all the write protections if there is any */
+ if (test_uffdio_wp)
+ wp_range(uffd, (unsigned long)area_dst,
+ nr_pages * page_size, false);
+
+ /* unregister */
+ if (ioctl(uffd, UFFDIO_UNREGISTER, &uffdio_register.range))
+ err("unregister failure");
+ if (area_dst_alias) {
+ uffdio_register.range.start = (unsigned long) area_dst;
+ if (ioctl(uffd, UFFDIO_UNREGISTER,
+ &uffdio_register.range))
+ err("unregister failure alias");
+ }
+
+ /* verification */
+ if (bounces & BOUNCE_VERIFY)
+ for (nr = 0; nr < nr_pages; nr++)
+ if (*area_count(area_dst, nr) != count_verify[nr])
+ err("error area_count %llu %llu %lu\n",
+ *area_count(area_src, nr),
+ count_verify[nr], nr);
+
+ /* prepare next bounce */
+ swap(area_src, area_dst);
+
+ swap(area_src_alias, area_dst_alias);
+
+ uffd_stats_report(uffd_stats, nr_cpus);
+ }
+
+ if (test_type == TEST_ANON) {
+ /*
+ * shmem/hugetlb won't be able to run since they have different
+ * behavior on fork() (file-backed memory normally drops ptes
+ * directly when fork), meanwhile the pagemap test will verify
+ * pgtable entry of fork()ed child.
+ */
+ userfaultfd_pagemap_test(page_size);
+ /*
+ * Hard-code for x86_64 for now for 2M THP, as x86_64 is
+ * currently the only one that supports uffd-wp
+ */
+ userfaultfd_pagemap_test(page_size * 512);
+ }
+
+ return userfaultfd_zeropage_test() || userfaultfd_sig_test()
+ || userfaultfd_events_test() || userfaultfd_minor_test();
+}
+
+/*
+ * Copied from mlock2-tests.c
+ */
+unsigned long default_huge_page_size(void)
+{
+ unsigned long hps = 0;
+ char *line = NULL;
+ size_t linelen = 0;
+ FILE *f = fopen("/proc/meminfo", "r");
+
+ if (!f)
+ return 0;
+ while (getline(&line, &linelen, f) > 0) {
+ if (sscanf(line, "Hugepagesize: %lu kB", &hps) == 1) {
+ hps <<= 10;
+ break;
+ }
+ }
+
+ free(line);
+ fclose(f);
+ return hps;
+}
+
+static void set_test_type(const char *type)
+{
+ if (!strcmp(type, "anon")) {
+ test_type = TEST_ANON;
+ uffd_test_ops = &anon_uffd_test_ops;
+ } else if (!strcmp(type, "hugetlb")) {
+ test_type = TEST_HUGETLB;
+ uffd_test_ops = &hugetlb_uffd_test_ops;
+ } else if (!strcmp(type, "hugetlb_shared")) {
+ map_shared = true;
+ test_type = TEST_HUGETLB;
+ uffd_test_ops = &hugetlb_uffd_test_ops;
+ /* Minor faults require shared hugetlb; only enable here. */
+ test_uffdio_minor = true;
+ } else if (!strcmp(type, "shmem")) {
+ map_shared = true;
+ test_type = TEST_SHMEM;
+ uffd_test_ops = &shmem_uffd_test_ops;
+ test_uffdio_minor = true;
+ }
+}
+
+static void parse_test_type_arg(const char *raw_type)
+{
+ char *buf = strdup(raw_type);
+ uint64_t features = UFFD_API_FEATURES;
+
+ while (buf) {
+ const char *token = strsep(&buf, ":");
+
+ if (!test_type)
+ set_test_type(token);
+ else if (!strcmp(token, "dev"))
+ test_dev_userfaultfd = true;
+ else if (!strcmp(token, "syscall"))
+ test_dev_userfaultfd = false;
+ else if (!strcmp(token, "collapse"))
+ test_collapse = true;
+ else
+ err("unrecognized test mod '%s'", token);
+ }
+
+ if (!test_type)
+ err("failed to parse test type argument: '%s'", raw_type);
+
+ if (test_collapse && test_type != TEST_SHMEM)
+ err("Unsupported test: %s", raw_type);
+
+ if (test_type == TEST_HUGETLB)
+ page_size = hpage_size;
+ else
+ page_size = sysconf(_SC_PAGE_SIZE);
+
+ if (!page_size)
+ err("Unable to determine page size");
+ if ((unsigned long) area_count(NULL, 0) + sizeof(unsigned long long) * 2
+ > page_size)
+ err("Impossible to run this test");
+
+ /*
+ * Whether we can test certain features depends not just on test type,
+ * but also on whether or not this particular kernel supports the
+ * feature.
+ */
+
+ userfaultfd_open(&features);
+
+ test_uffdio_wp = test_uffdio_wp &&
+ (features & UFFD_FEATURE_PAGEFAULT_FLAG_WP);
+ test_uffdio_minor = test_uffdio_minor &&
+ (features & uffd_minor_feature());
+
+ close(uffd);
+ uffd = -1;
+}
+
+static void sigalrm(int sig)
+{
+ if (sig != SIGALRM)
+ abort();
+ test_uffdio_copy_eexist = true;
+ test_uffdio_zeropage_eexist = true;
+ alarm(ALARM_INTERVAL_SECS);
+}
+
+int main(int argc, char **argv)
+{
+ size_t bytes;
+
+ if (argc < 4)
+ usage();
+
+ if (signal(SIGALRM, sigalrm) == SIG_ERR)
+ err("failed to arm SIGALRM");
+ alarm(ALARM_INTERVAL_SECS);
+
+ hpage_size = default_huge_page_size();
+ parse_test_type_arg(argv[1]);
+ bytes = atol(argv[2]) * 1024 * 1024;
+
+ if (test_collapse && bytes & (hpage_size - 1))
+ err("MiB must be multiple of %lu if :collapse mod set",
+ hpage_size >> 20);
+
+ nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+
+ if (test_collapse) {
+ /* nr_cpus must divide (bytes / page_size), otherwise,
+ * area allocations of (nr_pages * paze_size) won't be a
+ * multiple of hpage_size, even if bytes is a multiple of
+ * hpage_size.
+ *
+ * This means that nr_cpus must divide (N * (2 << (H-P))
+ * where:
+ * bytes = hpage_size * N
+ * hpage_size = 2 << H
+ * page_size = 2 << P
+ *
+ * And we want to chose nr_cpus to be the largest value
+ * satisfying this constraint, not larger than the number
+ * of online CPUs. Unfortunately, prime factorization of
+ * N and nr_cpus may be arbitrary, so have to search for it.
+ * Instead, just use the highest power of 2 dividing both
+ * nr_cpus and (bytes / page_size).
+ */
+ int x = factor_of_2(nr_cpus);
+ int y = factor_of_2(bytes / page_size);
+
+ nr_cpus = x < y ? x : y;
+ }
+ nr_pages_per_cpu = bytes / page_size / nr_cpus;
+ if (!nr_pages_per_cpu) {
+ _err("invalid MiB");
+ usage();
+ }
+
+ bounces = atoi(argv[3]);
+ if (bounces <= 0) {
+ _err("invalid bounces");
+ usage();
+ }
+ nr_pages = nr_pages_per_cpu * nr_cpus;
+
+ if (test_type == TEST_SHMEM || test_type == TEST_HUGETLB) {
+ unsigned int memfd_flags = 0;
+
+ if (test_type == TEST_HUGETLB)
+ memfd_flags = MFD_HUGETLB;
+ mem_fd = memfd_create(argv[0], memfd_flags);
+ if (mem_fd < 0)
+ err("memfd_create");
+ if (ftruncate(mem_fd, nr_pages * page_size * 2))
+ err("ftruncate");
+ if (fallocate(mem_fd,
+ FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0,
+ nr_pages * page_size * 2))
+ err("fallocate");
+ }
+ printf("nr_pages: %lu, nr_pages_per_cpu: %lu\n",
+ nr_pages, nr_pages_per_cpu);
+ return userfaultfd_stress();
+}
+
+#else /* __NR_userfaultfd */
+
+#warning "missing __NR_userfaultfd definition"
+
+int main(void)
+{
+ printf("skip: Skipping userfaultfd test (missing __NR_userfaultfd)\n");
+ return KSFT_SKIP;
+}
+
+#endif /* __NR_userfaultfd */
diff --git a/tools/testing/selftests/mm/util.h b/tools/testing/selftests/mm/util.h
new file mode 100644
index 000000000000..b27d26199334
--- /dev/null
+++ b/tools/testing/selftests/mm/util.h
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __KSELFTEST_VM_UTIL_H
+#define __KSELFTEST_VM_UTIL_H
+
+#include <stdint.h>
+#include <sys/mman.h>
+#include <err.h>
+#include <string.h> /* ffsl() */
+#include <unistd.h> /* _SC_PAGESIZE */
+
+static unsigned int __page_size;
+static unsigned int __page_shift;
+
+static inline unsigned int page_size(void)
+{
+ if (!__page_size)
+ __page_size = sysconf(_SC_PAGESIZE);
+ return __page_size;
+}
+
+static inline unsigned int page_shift(void)
+{
+ if (!__page_shift)
+ __page_shift = (ffsl(page_size()) - 1);
+ return __page_shift;
+}
+
+#define PAGE_SHIFT (page_shift())
+#define PAGE_SIZE (page_size())
+/*
+ * On ppc64 this will only work with radix 2M hugepage size
+ */
+#define HPAGE_SHIFT 21
+#define HPAGE_SIZE (1 << HPAGE_SHIFT)
+
+#define PAGEMAP_PRESENT(ent) (((ent) & (1ull << 63)) != 0)
+#define PAGEMAP_PFN(ent) ((ent) & ((1ull << 55) - 1))
+
+
+static inline int64_t allocate_transhuge(void *ptr, int pagemap_fd)
+{
+ uint64_t ent[2];
+
+ /* drop pmd */
+ if (mmap(ptr, HPAGE_SIZE, PROT_READ | PROT_WRITE,
+ MAP_FIXED | MAP_ANONYMOUS |
+ MAP_NORESERVE | MAP_PRIVATE, -1, 0) != ptr)
+ errx(2, "mmap transhuge");
+
+ if (madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE))
+ err(2, "MADV_HUGEPAGE");
+
+ /* allocate transparent huge page */
+ *(volatile void **)ptr = ptr;
+
+ if (pread(pagemap_fd, ent, sizeof(ent),
+ (uintptr_t)ptr >> (PAGE_SHIFT - 3)) != sizeof(ent))
+ err(2, "read pagemap");
+
+ if (PAGEMAP_PRESENT(ent[0]) && PAGEMAP_PRESENT(ent[1]) &&
+ PAGEMAP_PFN(ent[0]) + 1 == PAGEMAP_PFN(ent[1]) &&
+ !(PAGEMAP_PFN(ent[0]) & ((1 << (HPAGE_SHIFT - PAGE_SHIFT)) - 1)))
+ return PAGEMAP_PFN(ent[0]);
+
+ return -1;
+}
+
+#endif
diff --git a/tools/testing/selftests/mm/va_128TBswitch.c b/tools/testing/selftests/mm/va_128TBswitch.c
new file mode 100644
index 000000000000..1d2068989883
--- /dev/null
+++ b/tools/testing/selftests/mm/va_128TBswitch.c
@@ -0,0 +1,289 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Authors: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
+ * Authors: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ */
+
+#include <stdio.h>
+#include <sys/mman.h>
+#include <string.h>
+
+#include "../kselftest.h"
+
+#ifdef __powerpc64__
+#define PAGE_SIZE (64 << 10)
+/*
+ * This will work with 16M and 2M hugepage size
+ */
+#define HUGETLB_SIZE (16 << 20)
+#else
+#define PAGE_SIZE (4 << 10)
+#define HUGETLB_SIZE (2 << 20)
+#endif
+
+/*
+ * >= 128TB is the hint addr value we used to select
+ * large address space.
+ */
+#define ADDR_SWITCH_HINT (1UL << 47)
+#define LOW_ADDR ((void *) (1UL << 30))
+#define HIGH_ADDR ((void *) (1UL << 48))
+
+struct testcase {
+ void *addr;
+ unsigned long size;
+ unsigned long flags;
+ const char *msg;
+ unsigned int low_addr_required:1;
+ unsigned int keep_mapped:1;
+};
+
+static struct testcase testcases[] = {
+ {
+ /*
+ * If stack is moved, we could possibly allocate
+ * this at the requested address.
+ */
+ .addr = ((void *)(ADDR_SWITCH_HINT - PAGE_SIZE)),
+ .size = PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, PAGE_SIZE)",
+ .low_addr_required = 1,
+ },
+ {
+ /*
+ * We should never allocate at the requested address or above it
+ * The len cross the 128TB boundary. Without MAP_FIXED
+ * we will always search in the lower address space.
+ */
+ .addr = ((void *)(ADDR_SWITCH_HINT - PAGE_SIZE)),
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, (2 * PAGE_SIZE))",
+ .low_addr_required = 1,
+ },
+ {
+ /*
+ * Exact mapping at 128TB, the area is free we should get that
+ * even without MAP_FIXED.
+ */
+ .addr = ((void *)(ADDR_SWITCH_HINT)),
+ .size = PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(ADDR_SWITCH_HINT, PAGE_SIZE)",
+ .keep_mapped = 1,
+ },
+ {
+ .addr = (void *)(ADDR_SWITCH_HINT),
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+ .msg = "mmap(ADDR_SWITCH_HINT, 2 * PAGE_SIZE, MAP_FIXED)",
+ },
+ {
+ .addr = NULL,
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(NULL)",
+ .low_addr_required = 1,
+ },
+ {
+ .addr = LOW_ADDR,
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(LOW_ADDR)",
+ .low_addr_required = 1,
+ },
+ {
+ .addr = HIGH_ADDR,
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(HIGH_ADDR)",
+ .keep_mapped = 1,
+ },
+ {
+ .addr = HIGH_ADDR,
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(HIGH_ADDR) again",
+ .keep_mapped = 1,
+ },
+ {
+ .addr = HIGH_ADDR,
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+ .msg = "mmap(HIGH_ADDR, MAP_FIXED)",
+ },
+ {
+ .addr = (void *) -1,
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(-1)",
+ .keep_mapped = 1,
+ },
+ {
+ .addr = (void *) -1,
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(-1) again",
+ },
+ {
+ .addr = ((void *)(ADDR_SWITCH_HINT - PAGE_SIZE)),
+ .size = PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, PAGE_SIZE)",
+ .low_addr_required = 1,
+ },
+ {
+ .addr = (void *)(ADDR_SWITCH_HINT - PAGE_SIZE),
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, 2 * PAGE_SIZE)",
+ .low_addr_required = 1,
+ .keep_mapped = 1,
+ },
+ {
+ .addr = (void *)(ADDR_SWITCH_HINT - PAGE_SIZE / 2),
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE/2 , 2 * PAGE_SIZE)",
+ .low_addr_required = 1,
+ .keep_mapped = 1,
+ },
+ {
+ .addr = ((void *)(ADDR_SWITCH_HINT)),
+ .size = PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(ADDR_SWITCH_HINT, PAGE_SIZE)",
+ },
+ {
+ .addr = (void *)(ADDR_SWITCH_HINT),
+ .size = 2 * PAGE_SIZE,
+ .flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+ .msg = "mmap(ADDR_SWITCH_HINT, 2 * PAGE_SIZE, MAP_FIXED)",
+ },
+};
+
+static struct testcase hugetlb_testcases[] = {
+ {
+ .addr = NULL,
+ .size = HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(NULL, MAP_HUGETLB)",
+ .low_addr_required = 1,
+ },
+ {
+ .addr = LOW_ADDR,
+ .size = HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(LOW_ADDR, MAP_HUGETLB)",
+ .low_addr_required = 1,
+ },
+ {
+ .addr = HIGH_ADDR,
+ .size = HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(HIGH_ADDR, MAP_HUGETLB)",
+ .keep_mapped = 1,
+ },
+ {
+ .addr = HIGH_ADDR,
+ .size = HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(HIGH_ADDR, MAP_HUGETLB) again",
+ .keep_mapped = 1,
+ },
+ {
+ .addr = HIGH_ADDR,
+ .size = HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+ .msg = "mmap(HIGH_ADDR, MAP_FIXED | MAP_HUGETLB)",
+ },
+ {
+ .addr = (void *) -1,
+ .size = HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(-1, MAP_HUGETLB)",
+ .keep_mapped = 1,
+ },
+ {
+ .addr = (void *) -1,
+ .size = HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(-1, MAP_HUGETLB) again",
+ },
+ {
+ .addr = (void *)(ADDR_SWITCH_HINT - PAGE_SIZE),
+ .size = 2 * HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS,
+ .msg = "mmap(ADDR_SWITCH_HINT - PAGE_SIZE, 2*HUGETLB_SIZE, MAP_HUGETLB)",
+ .low_addr_required = 1,
+ .keep_mapped = 1,
+ },
+ {
+ .addr = (void *)(ADDR_SWITCH_HINT),
+ .size = 2 * HUGETLB_SIZE,
+ .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED,
+ .msg = "mmap(ADDR_SWITCH_HINT , 2*HUGETLB_SIZE, MAP_FIXED | MAP_HUGETLB)",
+ },
+};
+
+static int run_test(struct testcase *test, int count)
+{
+ void *p;
+ int i, ret = KSFT_PASS;
+
+ for (i = 0; i < count; i++) {
+ struct testcase *t = test + i;
+
+ p = mmap(t->addr, t->size, PROT_READ | PROT_WRITE, t->flags, -1, 0);
+
+ printf("%s: %p - ", t->msg, p);
+
+ if (p == MAP_FAILED) {
+ printf("FAILED\n");
+ ret = KSFT_FAIL;
+ continue;
+ }
+
+ if (t->low_addr_required && p >= (void *)(ADDR_SWITCH_HINT)) {
+ printf("FAILED\n");
+ ret = KSFT_FAIL;
+ } else {
+ /*
+ * Do a dereference of the address returned so that we catch
+ * bugs in page fault handling
+ */
+ memset(p, 0, t->size);
+ printf("OK\n");
+ }
+ if (!t->keep_mapped)
+ munmap(p, t->size);
+ }
+
+ return ret;
+}
+
+static int supported_arch(void)
+{
+#if defined(__powerpc64__)
+ return 1;
+#elif defined(__x86_64__)
+ return 1;
+#else
+ return 0;
+#endif
+}
+
+int main(int argc, char **argv)
+{
+ int ret;
+
+ if (!supported_arch())
+ return KSFT_SKIP;
+
+ ret = run_test(testcases, ARRAY_SIZE(testcases));
+ if (argc == 2 && !strcmp(argv[1], "--run-hugetlb"))
+ ret = run_test(hugetlb_testcases, ARRAY_SIZE(hugetlb_testcases));
+ return ret;
+}
diff --git a/tools/testing/selftests/mm/va_128TBswitch.sh b/tools/testing/selftests/mm/va_128TBswitch.sh
new file mode 100644
index 000000000000..41580751dc51
--- /dev/null
+++ b/tools/testing/selftests/mm/va_128TBswitch.sh
@@ -0,0 +1,54 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (C) 2022 Adam Sindelar (Meta) <adam@wowsignal.io>
+#
+# This is a test for mmap behavior with 5-level paging. This script wraps the
+# real test to check that the kernel is configured to support at least 5
+# pagetable levels.
+
+# 1 means the test failed
+exitcode=1
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+fail()
+{
+ echo "$1"
+ exit $exitcode
+}
+
+check_supported_x86_64()
+{
+ local config="/proc/config.gz"
+ [[ -f "${config}" ]] || config="/boot/config-$(uname -r)"
+ [[ -f "${config}" ]] || fail "Cannot find kernel config in /proc or /boot"
+
+ # gzip -dcfq automatically handles both compressed and plaintext input.
+ # See man 1 gzip under '-f'.
+ local pg_table_levels=$(gzip -dcfq "${config}" | grep PGTABLE_LEVELS | cut -d'=' -f 2)
+
+ if [[ "${pg_table_levels}" -lt 5 ]]; then
+ echo "$0: PGTABLE_LEVELS=${pg_table_levels}, must be >= 5 to run this test"
+ exit $ksft_skip
+ fi
+}
+
+check_test_requirements()
+{
+ # The test supports x86_64 and powerpc64. We currently have no useful
+ # eligibility check for powerpc64, and the test itself will reject other
+ # architectures.
+ case `uname -m` in
+ "x86_64")
+ check_supported_x86_64
+ ;;
+ *)
+ return 0
+ ;;
+ esac
+}
+
+check_test_requirements
+./va_128TBswitch
diff --git a/tools/testing/selftests/mm/virtual_address_range.c b/tools/testing/selftests/mm/virtual_address_range.c
new file mode 100644
index 000000000000..c0592646ed93
--- /dev/null
+++ b/tools/testing/selftests/mm/virtual_address_range.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2017, Anshuman Khandual, IBM Corp.
+ *
+ * Works on architectures which support 128TB virtual
+ * address range and beyond.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/mman.h>
+#include <sys/time.h>
+
+/*
+ * Maximum address range mapped with a single mmap()
+ * call is little bit more than 16GB. Hence 16GB is
+ * chosen as the single chunk size for address space
+ * mapping.
+ */
+#define MAP_CHUNK_SIZE 17179869184UL /* 16GB */
+
+/*
+ * Address space till 128TB is mapped without any hint
+ * and is enabled by default. Address space beyond 128TB
+ * till 512TB is obtained by passing hint address as the
+ * first argument into mmap() system call.
+ *
+ * The process heap address space is divided into two
+ * different areas one below 128TB and one above 128TB
+ * till it reaches 512TB. One with size 128TB and the
+ * other being 384TB.
+ *
+ * On Arm64 the address space is 256TB and no high mappings
+ * are supported so far.
+ */
+
+#define NR_CHUNKS_128TB 8192UL /* Number of 16GB chunks for 128TB */
+#define NR_CHUNKS_256TB (NR_CHUNKS_128TB * 2UL)
+#define NR_CHUNKS_384TB (NR_CHUNKS_128TB * 3UL)
+
+#define ADDR_MARK_128TB (1UL << 47) /* First address beyond 128TB */
+#define ADDR_MARK_256TB (1UL << 48) /* First address beyond 256TB */
+
+#ifdef __aarch64__
+#define HIGH_ADDR_MARK ADDR_MARK_256TB
+#define HIGH_ADDR_SHIFT 49
+#define NR_CHUNKS_LOW NR_CHUNKS_256TB
+#define NR_CHUNKS_HIGH 0
+#else
+#define HIGH_ADDR_MARK ADDR_MARK_128TB
+#define HIGH_ADDR_SHIFT 48
+#define NR_CHUNKS_LOW NR_CHUNKS_128TB
+#define NR_CHUNKS_HIGH NR_CHUNKS_384TB
+#endif
+
+static char *hind_addr(void)
+{
+ int bits = HIGH_ADDR_SHIFT + rand() % (63 - HIGH_ADDR_SHIFT);
+
+ return (char *) (1UL << bits);
+}
+
+static int validate_addr(char *ptr, int high_addr)
+{
+ unsigned long addr = (unsigned long) ptr;
+
+ if (high_addr) {
+ if (addr < HIGH_ADDR_MARK) {
+ printf("Bad address %lx\n", addr);
+ return 1;
+ }
+ return 0;
+ }
+
+ if (addr > HIGH_ADDR_MARK) {
+ printf("Bad address %lx\n", addr);
+ return 1;
+ }
+ return 0;
+}
+
+static int validate_lower_address_hint(void)
+{
+ char *ptr;
+
+ ptr = mmap((void *) (1UL << 45), MAP_CHUNK_SIZE, PROT_READ |
+ PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+ if (ptr == MAP_FAILED)
+ return 0;
+
+ return 1;
+}
+
+int main(int argc, char *argv[])
+{
+ char *ptr[NR_CHUNKS_LOW];
+ char *hptr[NR_CHUNKS_HIGH];
+ char *hint;
+ unsigned long i, lchunks, hchunks;
+
+ for (i = 0; i < NR_CHUNKS_LOW; i++) {
+ ptr[i] = mmap(NULL, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+ if (ptr[i] == MAP_FAILED) {
+ if (validate_lower_address_hint())
+ return 1;
+ break;
+ }
+
+ if (validate_addr(ptr[i], 0))
+ return 1;
+ }
+ lchunks = i;
+
+ for (i = 0; i < NR_CHUNKS_HIGH; i++) {
+ hint = hind_addr();
+ hptr[i] = mmap(hint, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+
+ if (hptr[i] == MAP_FAILED)
+ break;
+
+ if (validate_addr(hptr[i], 1))
+ return 1;
+ }
+ hchunks = i;
+
+ for (i = 0; i < lchunks; i++)
+ munmap(ptr[i], MAP_CHUNK_SIZE);
+
+ for (i = 0; i < hchunks; i++)
+ munmap(hptr[i], MAP_CHUNK_SIZE);
+
+ return 0;
+}
diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
new file mode 100644
index 000000000000..40e795624ff3
--- /dev/null
+++ b/tools/testing/selftests/mm/vm_util.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <string.h>
+#include <fcntl.h>
+#include "../kselftest.h"
+#include "vm_util.h"
+
+#define PMD_SIZE_FILE_PATH "/sys/kernel/mm/transparent_hugepage/hpage_pmd_size"
+#define SMAP_FILE_PATH "/proc/self/smaps"
+#define MAX_LINE_LENGTH 500
+
+uint64_t pagemap_get_entry(int fd, char *start)
+{
+ const unsigned long pfn = (unsigned long)start / getpagesize();
+ uint64_t entry;
+ int ret;
+
+ ret = pread(fd, &entry, sizeof(entry), pfn * sizeof(entry));
+ if (ret != sizeof(entry))
+ ksft_exit_fail_msg("reading pagemap failed\n");
+ return entry;
+}
+
+bool pagemap_is_softdirty(int fd, char *start)
+{
+ uint64_t entry = pagemap_get_entry(fd, start);
+
+ // Check if dirty bit (55th bit) is set
+ return entry & 0x0080000000000000ull;
+}
+
+bool pagemap_is_swapped(int fd, char *start)
+{
+ uint64_t entry = pagemap_get_entry(fd, start);
+
+ return entry & 0x4000000000000000ull;
+}
+
+bool pagemap_is_populated(int fd, char *start)
+{
+ uint64_t entry = pagemap_get_entry(fd, start);
+
+ /* Present or swapped. */
+ return entry & 0xc000000000000000ull;
+}
+
+unsigned long pagemap_get_pfn(int fd, char *start)
+{
+ uint64_t entry = pagemap_get_entry(fd, start);
+
+ /* If present (63th bit), PFN is at bit 0 -- 54. */
+ if (entry & 0x8000000000000000ull)
+ return entry & 0x007fffffffffffffull;
+ return -1ul;
+}
+
+void clear_softdirty(void)
+{
+ int ret;
+ const char *ctrl = "4";
+ int fd = open("/proc/self/clear_refs", O_WRONLY);
+
+ if (fd < 0)
+ ksft_exit_fail_msg("opening clear_refs failed\n");
+ ret = write(fd, ctrl, strlen(ctrl));
+ close(fd);
+ if (ret != strlen(ctrl))
+ ksft_exit_fail_msg("writing clear_refs failed\n");
+}
+
+bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len)
+{
+ while (fgets(buf, len, fp)) {
+ if (!strncmp(buf, pattern, strlen(pattern)))
+ return true;
+ }
+ return false;
+}
+
+uint64_t read_pmd_pagesize(void)
+{
+ int fd;
+ char buf[20];
+ ssize_t num_read;
+
+ fd = open(PMD_SIZE_FILE_PATH, O_RDONLY);
+ if (fd == -1)
+ ksft_exit_fail_msg("Open hpage_pmd_size failed\n");
+
+ num_read = read(fd, buf, 19);
+ if (num_read < 1) {
+ close(fd);
+ ksft_exit_fail_msg("Read hpage_pmd_size failed\n");
+ }
+ buf[num_read] = '\0';
+ close(fd);
+
+ return strtoul(buf, NULL, 10);
+}
+
+bool __check_huge(void *addr, char *pattern, int nr_hpages,
+ uint64_t hpage_size)
+{
+ uint64_t thp = -1;
+ int ret;
+ FILE *fp;
+ char buffer[MAX_LINE_LENGTH];
+ char addr_pattern[MAX_LINE_LENGTH];
+
+ ret = snprintf(addr_pattern, MAX_LINE_LENGTH, "%08lx-",
+ (unsigned long) addr);
+ if (ret >= MAX_LINE_LENGTH)
+ ksft_exit_fail_msg("%s: Pattern is too long\n", __func__);
+
+ fp = fopen(SMAP_FILE_PATH, "r");
+ if (!fp)
+ ksft_exit_fail_msg("%s: Failed to open file %s\n", __func__, SMAP_FILE_PATH);
+
+ if (!check_for_pattern(fp, addr_pattern, buffer, sizeof(buffer)))
+ goto err_out;
+
+ /*
+ * Fetch the pattern in the same block and check the number of
+ * hugepages.
+ */
+ if (!check_for_pattern(fp, pattern, buffer, sizeof(buffer)))
+ goto err_out;
+
+ snprintf(addr_pattern, MAX_LINE_LENGTH, "%s%%9ld kB", pattern);
+
+ if (sscanf(buffer, addr_pattern, &thp) != 1)
+ ksft_exit_fail_msg("Reading smap error\n");
+
+err_out:
+ fclose(fp);
+ return thp == (nr_hpages * (hpage_size >> 10));
+}
+
+bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size)
+{
+ return __check_huge(addr, "AnonHugePages: ", nr_hpages, hpage_size);
+}
+
+bool check_huge_file(void *addr, int nr_hpages, uint64_t hpage_size)
+{
+ return __check_huge(addr, "FilePmdMapped:", nr_hpages, hpage_size);
+}
+
+bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size)
+{
+ return __check_huge(addr, "ShmemPmdMapped:", nr_hpages, hpage_size);
+}
diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
new file mode 100644
index 000000000000..1995ee911ef2
--- /dev/null
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <stdint.h>
+#include <stdbool.h>
+
+uint64_t pagemap_get_entry(int fd, char *start);
+bool pagemap_is_softdirty(int fd, char *start);
+bool pagemap_is_swapped(int fd, char *start);
+bool pagemap_is_populated(int fd, char *start);
+unsigned long pagemap_get_pfn(int fd, char *start);
+void clear_softdirty(void);
+bool check_for_pattern(FILE *fp, const char *pattern, char *buf, size_t len);
+uint64_t read_pmd_pagesize(void);
+bool check_huge_anon(void *addr, int nr_hpages, uint64_t hpage_size);
+bool check_huge_file(void *addr, int nr_hpages, uint64_t hpage_size);
+bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size);
diff --git a/tools/testing/selftests/mm/write_hugetlb_memory.sh b/tools/testing/selftests/mm/write_hugetlb_memory.sh
new file mode 100644
index 000000000000..70a02301f4c2
--- /dev/null
+++ b/tools/testing/selftests/mm/write_hugetlb_memory.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+set -e
+
+size=$1
+populate=$2
+write=$3
+cgroup=$4
+path=$5
+method=$6
+private=$7
+want_sleep=$8
+reserve=$9
+
+echo "Putting task in cgroup '$cgroup'"
+echo $$ > ${cgroup_path:-/dev/cgroup/memory}/"$cgroup"/cgroup.procs
+
+echo "Method is $method"
+
+set +e
+./write_to_hugetlbfs -p "$path" -s "$size" "$write" "$populate" -m "$method" \
+ "$private" "$want_sleep" "$reserve"
diff --git a/tools/testing/selftests/mm/write_to_hugetlbfs.c b/tools/testing/selftests/mm/write_to_hugetlbfs.c
new file mode 100644
index 000000000000..6a2caba19ee1
--- /dev/null
+++ b/tools/testing/selftests/mm/write_to_hugetlbfs.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This program reserves and uses hugetlb memory, supporting a bunch of
+ * scenarios needed by the charged_reserved_hugetlb.sh test.
+ */
+
+#include <err.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/shm.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+/* Global definitions. */
+enum method {
+ HUGETLBFS,
+ MMAP_MAP_HUGETLB,
+ SHM,
+ MAX_METHOD
+};
+
+
+/* Global variables. */
+static const char *self;
+static char *shmaddr;
+static int shmid;
+
+/*
+ * Show usage and exit.
+ */
+static void exit_usage(void)
+{
+ printf("Usage: %s -p <path to hugetlbfs file> -s <size to map> "
+ "[-m <0=hugetlbfs | 1=mmap(MAP_HUGETLB)>] [-l] [-r] "
+ "[-o] [-w] [-n]\n",
+ self);
+ exit(EXIT_FAILURE);
+}
+
+void sig_handler(int signo)
+{
+ printf("Received %d.\n", signo);
+ if (signo == SIGINT) {
+ printf("Deleting the memory\n");
+ if (shmdt((const void *)shmaddr) != 0) {
+ perror("Detach failure");
+ shmctl(shmid, IPC_RMID, NULL);
+ exit(4);
+ }
+
+ shmctl(shmid, IPC_RMID, NULL);
+ printf("Done deleting the memory\n");
+ }
+ exit(2);
+}
+
+int main(int argc, char **argv)
+{
+ int fd = 0;
+ int key = 0;
+ int *ptr = NULL;
+ int c = 0;
+ int size = 0;
+ char path[256] = "";
+ enum method method = MAX_METHOD;
+ int want_sleep = 0, private = 0;
+ int populate = 0;
+ int write = 0;
+ int reserve = 1;
+
+ if (signal(SIGINT, sig_handler) == SIG_ERR)
+ err(1, "\ncan't catch SIGINT\n");
+
+ /* Parse command-line arguments. */
+ setvbuf(stdout, NULL, _IONBF, 0);
+ self = argv[0];
+
+ while ((c = getopt(argc, argv, "s:p:m:owlrn")) != -1) {
+ switch (c) {
+ case 's':
+ size = atoi(optarg);
+ break;
+ case 'p':
+ strncpy(path, optarg, sizeof(path));
+ break;
+ case 'm':
+ if (atoi(optarg) >= MAX_METHOD) {
+ errno = EINVAL;
+ perror("Invalid -m.");
+ exit_usage();
+ }
+ method = atoi(optarg);
+ break;
+ case 'o':
+ populate = 1;
+ break;
+ case 'w':
+ write = 1;
+ break;
+ case 'l':
+ want_sleep = 1;
+ break;
+ case 'r':
+ private
+ = 1;
+ break;
+ case 'n':
+ reserve = 0;
+ break;
+ default:
+ errno = EINVAL;
+ perror("Invalid arg");
+ exit_usage();
+ }
+ }
+
+ if (strncmp(path, "", sizeof(path)) != 0) {
+ printf("Writing to this path: %s\n", path);
+ } else {
+ errno = EINVAL;
+ perror("path not found");
+ exit_usage();
+ }
+
+ if (size != 0) {
+ printf("Writing this size: %d\n", size);
+ } else {
+ errno = EINVAL;
+ perror("size not found");
+ exit_usage();
+ }
+
+ if (!populate)
+ printf("Not populating.\n");
+ else
+ printf("Populating.\n");
+
+ if (!write)
+ printf("Not writing to memory.\n");
+
+ if (method == MAX_METHOD) {
+ errno = EINVAL;
+ perror("-m Invalid");
+ exit_usage();
+ } else
+ printf("Using method=%d\n", method);
+
+ if (!private)
+ printf("Shared mapping.\n");
+ else
+ printf("Private mapping.\n");
+
+ if (!reserve)
+ printf("NO_RESERVE mapping.\n");
+ else
+ printf("RESERVE mapping.\n");
+
+ switch (method) {
+ case HUGETLBFS:
+ printf("Allocating using HUGETLBFS.\n");
+ fd = open(path, O_CREAT | O_RDWR, 0777);
+ if (fd == -1)
+ err(1, "Failed to open file.");
+
+ ptr = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ (private ? MAP_PRIVATE : MAP_SHARED) |
+ (populate ? MAP_POPULATE : 0) |
+ (reserve ? 0 : MAP_NORESERVE),
+ fd, 0);
+
+ if (ptr == MAP_FAILED) {
+ close(fd);
+ err(1, "Error mapping the file");
+ }
+ break;
+ case MMAP_MAP_HUGETLB:
+ printf("Allocating using MAP_HUGETLB.\n");
+ ptr = mmap(NULL, size, PROT_READ | PROT_WRITE,
+ (private ? (MAP_PRIVATE | MAP_ANONYMOUS) :
+ MAP_SHARED) |
+ MAP_HUGETLB | (populate ? MAP_POPULATE : 0) |
+ (reserve ? 0 : MAP_NORESERVE),
+ -1, 0);
+
+ if (ptr == MAP_FAILED)
+ err(1, "mmap");
+
+ printf("Returned address is %p\n", ptr);
+ break;
+ case SHM:
+ printf("Allocating using SHM.\n");
+ shmid = shmget(key, size,
+ SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
+ if (shmid < 0) {
+ shmid = shmget(++key, size,
+ SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
+ if (shmid < 0)
+ err(1, "shmget");
+ }
+ printf("shmid: 0x%x, shmget key:%d\n", shmid, key);
+
+ ptr = shmat(shmid, NULL, 0);
+ if (ptr == (int *)-1) {
+ perror("Shared memory attach failure");
+ shmctl(shmid, IPC_RMID, NULL);
+ exit(2);
+ }
+ printf("shmaddr: %p\n", ptr);
+
+ break;
+ default:
+ errno = EINVAL;
+ err(1, "Invalid method.");
+ }
+
+ if (write) {
+ printf("Writing to memory.\n");
+ memset(ptr, 1, size);
+ }
+
+ if (want_sleep) {
+ /* Signal to caller that we're done. */
+ printf("DONE\n");
+
+ /* Hold memory until external kill signal is delivered. */
+ while (1)
+ sleep(100);
+ }
+
+ if (method == HUGETLBFS)
+ close(fd);
+
+ return 0;
+}