1 files changed, 85 insertions, 0 deletions
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
new file mode 100644
index 000000000000..9ebb5e590f93
--- /dev/null
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -0,0 +1,85 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# Copied from arch/tile/kernel/vdso/Makefile
+
+# Include the generic Makefile to check the built vdso.
+include $(srctree)/lib/vdso/Makefile.include
+# Symbols present in the vdso
+vdso-syms  = rt_sigreturn
+ifdef CONFIG_64BIT
+vdso-syms += vgettimeofday
+endif
+vdso-syms += getcpu
+vdso-syms += flush_icache
+vdso-syms += hwprobe
+vdso-syms += sys_hwprobe
+
+ifdef CONFIG_VDSO_GETRANDOM
+vdso-syms += getrandom
+endif
+
+# Files to link into the vdso
+obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
+
+ifdef CONFIG_VDSO_GETRANDOM
+obj-vdso += vgetrandom-chacha.o
+endif
+
+ccflags-y := -fno-stack-protector
+ccflags-y += -DDISABLE_BRANCH_PROFILING
+ccflags-y += -fno-builtin
+
+ifneq ($(c-gettimeofday-y),)
+  CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y)
+endif
+
+ifneq ($(c-getrandom-y),)
+  CFLAGS_getrandom.o += -fPIC -include $(c-getrandom-y)
+endif
+
+CFLAGS_hwprobe.o += -fPIC
+
+# Build rules
+targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds
+obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
+
+obj-y += vdso.o
+CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
+ifneq ($(filter vgettimeofday, $(vdso-syms)),)
+CPPFLAGS_vdso.lds += -DHAS_VGETTIMEOFDAY
+endif
+
+# Disable -pg to prevent insert call site
+CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
+CFLAGS_REMOVE_getrandom.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
+CFLAGS_REMOVE_hwprobe.o = $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS)
+
+# Force dependency
+$(obj)/vdso.o: $(obj)/vdso.so
+
+# link rule for the .so file, .lds has to be first
+$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
+	$(call if_changed,vdsold_and_check)
+LDFLAGS_vdso.so.dbg = -shared -soname=linux-vdso.so.1 \
+	--build-id=sha1 --eh-frame-hdr
+
+# strip rule for the .so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+	$(call if_changed,objcopy)
+
+# Generate VDSO offsets using helper script
+gen-vdsosym := $(src)/gen_vdso_offsets.sh
+quiet_cmd_vdsosym = VDSOSYM $@
+	cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
+
+include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
+	$(call if_changed,vdsosym)
+
+# actual build commands
+# The DSO images are built using a special linker script
+# Make sure only to export the intended __vdso_xxx symbol offsets.
+quiet_cmd_vdsold_and_check = VDSOLD  $@
+      cmd_vdsold_and_check = $(LD) $(ld_flags) -T $(filter-out FORCE,$^) -o $@.tmp && \
+                   $(OBJCOPY) $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \
+                   rm $@.tmp && \
+                   $(cmd_vdso_check)