diff options
Diffstat (limited to 'scripts/Makefile.build')
| -rw-r--r-- | scripts/Makefile.build | 718 |
1 files changed, 414 insertions, 304 deletions
diff --git a/scripts/Makefile.build b/scripts/Makefile.build index d5d859c80729..52c08c4eb0b9 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -1,11 +1,12 @@ +# SPDX-License-Identifier: GPL-2.0 # ========================================================================== # Building # ========================================================================== -src := $(obj) +src := $(srcroot)/$(obj) -PHONY := __build -__build: +PHONY := $(obj)/ +$(obj)/: # Init all relevant variables used in kbuild files so # 1) they have correct type @@ -14,16 +15,14 @@ obj-y := obj-m := lib-y := lib-m := -always := +always-y := +always-m := targets := subdir-y := subdir-m := -EXTRA_AFLAGS := -EXTRA_CFLAGS := -EXTRA_CPPFLAGS := -EXTRA_LDFLAGS := asflags-y := ccflags-y := +rustflags-y := cppflags-y := ldflags-y := @@ -31,245 +30,225 @@ subdir-asflags-y := subdir-ccflags-y := # Read auto.conf if it exists, otherwise ignore --include include/config/auto.conf +-include $(objtree)/include/config/auto.conf -include scripts/Kbuild.include +include $(srctree)/scripts/Kbuild.include +include $(srctree)/scripts/Makefile.compiler +include $(kbuild-file) +include $(srctree)/scripts/Makefile.lib -# For backward compatibility check that these variables do not change -save-cflags := $(CFLAGS) +# flags that take effect in current and sub directories +KBUILD_AFLAGS += $(subdir-asflags-y) +KBUILD_CFLAGS += $(subdir-ccflags-y) +KBUILD_RUSTFLAGS += $(subdir-rustflags-y) -# The filename Kbuild has precedence over Makefile -kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src)) -kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile) -include $(kbuild-file) +# Figure out what we need to build from the various variables +# =========================================================================== -# If the save-* variables changed error out -ifeq ($(KBUILD_NOPEDANTIC),) - ifneq ("$(save-cflags)","$(CFLAGS)") - $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y) - endif -endif +# When an object is listed to be built compiled-in and modular, +# only build the compiled-in version +obj-m := $(filter-out $(obj-y),$(obj-m)) -# -# make W=... settings -# -# W=1 - warnings that may be relevant and does not occur too often -# W=2 - warnings that occur quite often but may still be relevant -# W=3 - the more obscure warnings, can most likely be ignored -# -# $(call cc-option, -W...) handles gcc -W.. options which -# are not supported by all versions of the compiler -ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS -warning- := $(empty) - -warning-1 := -Wextra -Wunused -Wno-unused-parameter -warning-1 += -Wmissing-declarations -warning-1 += -Wmissing-format-attribute -warning-1 += -Wmissing-prototypes -warning-1 += -Wold-style-definition -warning-1 += $(call cc-option, -Wmissing-include-dirs) -warning-1 += $(call cc-option, -Wunused-but-set-variable) -warning-1 += $(call cc-disable-warning, missing-field-initializers) - -warning-2 := -Waggregate-return -warning-2 += -Wcast-align -warning-2 += -Wdisabled-optimization -warning-2 += -Wnested-externs -warning-2 += -Wshadow -warning-2 += $(call cc-option, -Wlogical-op) -warning-2 += $(call cc-option, -Wmissing-field-initializers) - -warning-3 := -Wbad-function-cast -warning-3 += -Wcast-qual -warning-3 += -Wconversion -warning-3 += -Wpacked -warning-3 += -Wpadded -warning-3 += -Wpointer-arith -warning-3 += -Wredundant-decls -warning-3 += -Wswitch-default -warning-3 += $(call cc-option, -Wpacked-bitfield-compat) -warning-3 += $(call cc-option, -Wvla) - -warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) -warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) -warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS))) - -ifeq ("$(strip $(warning))","") - $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) -endif +# Libraries are always collected in one lib file. +# Filter out objects already built-in +lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m))) -KBUILD_CFLAGS += $(warning) -endif +# Subdirectories we need to descend into +subdir-ym := $(sort $(subdir-y) $(subdir-m) \ + $(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m)))) -include scripts/Makefile.lib +# Handle objects in subdirs: +# - If we encounter foo/ in $(obj-y), replace it by foo/built-in.a and +# foo/modules.order +# - If we encounter foo/ in $(obj-m), replace it by foo/modules.order +# +# Generate modules.order to determine modorder. Unfortunately, we don't have +# information about ordering between -y and -m subdirs. Just put -y's first. -ifdef host-progs -ifneq ($(hostprogs-y),$(host-progs)) -$(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!) -hostprogs-y += $(host-progs) -endif +ifdef need-modorder +obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m)) +else +obj-m := $(filter-out %/, $(obj-m)) endif -# Do not include host rules unless needed -ifneq ($(hostprogs-y)$(hostprogs-m),) -include scripts/Makefile.host +ifdef need-builtin +obj-y := $(patsubst %/, %/built-in.a, $(obj-y)) +else +obj-y := $(filter-out %/, $(obj-y)) endif -ifneq ($(KBUILD_SRC),) -# Create output directory if not already present -_dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj)) - -# Create directories for object files if directory does not exist -# Needed when obj-y := dir/file.o syntax is used -_dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d))) +# Expand $(foo-objs) $(foo-y) etc. by replacing their individuals +suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s)))) +# List composite targets that are constructed by combining other targets +multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m))) +# List primitive targets that are compiled from source files +real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m)) + +# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object +multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y) +multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m) +multi-obj-ym := $(multi-obj-y) $(multi-obj-m) + +# Replace multi-part objects by their individual parts, +# including built-in.a from subdirectories +real-obj-y := $(call real-search, $(obj-y), .o, -objs -y) +real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m) + +always-y += $(always-m) + +# hostprogs-always-y += foo +# ... is a shorthand for +# hostprogs += foo +# always-y += foo +hostprogs += $(hostprogs-always-y) $(hostprogs-always-m) +always-y += $(hostprogs-always-y) $(hostprogs-always-m) + +# userprogs-always-y is likewise. +userprogs += $(userprogs-always-y) $(userprogs-always-m) +always-y += $(userprogs-always-y) $(userprogs-always-m) + +# Add subdir path + +ifneq ($(obj),.) +extra-y := $(addprefix $(obj)/, $(extra-y)) +always-y := $(addprefix $(obj)/, $(always-y)) +targets := $(addprefix $(obj)/, $(targets)) +obj-m := $(addprefix $(obj)/, $(obj-m)) +lib-y := $(addprefix $(obj)/, $(lib-y)) +real-obj-y := $(addprefix $(obj)/, $(real-obj-y)) +real-obj-m := $(addprefix $(obj)/, $(real-obj-m)) +multi-obj-m := $(addprefix $(obj)/, $(multi-obj-m)) +subdir-ym := $(addprefix $(obj)/, $(subdir-ym)) endif ifndef obj $(warning kbuild: Makefile.build is included improperly) endif +ifeq ($(need-modorder),) +ifneq ($(obj-m),) +$(warning $(patsubst %.o,'%.ko',$(obj-m)) will not be built even though obj-m is specified.) +$(warning You cannot use subdir-y/m to visit a module Makefile. Use obj-y/m instead.) +endif +endif + # =========================================================================== -ifneq ($(strip $(lib-y) $(lib-m) $(lib-n) $(lib-)),) -lib-target := $(obj)/lib.a +# subdir-builtin and subdir-modorder may contain duplications. Use $(sort ...) +subdir-builtin := $(sort $(filter %/built-in.a, $(real-obj-y))) +subdir-modorder := $(sort $(filter %/modules.order, $(obj-m))) + +targets-for-builtin := $(extra-y) + +ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),) +targets-for-builtin += $(obj)/lib.a endif -ifneq ($(strip $(obj-y) $(obj-m) $(obj-n) $(obj-) $(subdir-m) $(lib-target)),) -builtin-target := $(obj)/built-in.o +ifdef need-builtin +targets-for-builtin += $(obj)/built-in.a endif -modorder-target := $(obj)/modules.order +targets-for-modules := $(foreach x, o mod, \ + $(patsubst %.o, %.$x, $(filter %.o, $(obj-m)))) -# We keep a list of all modules in $(MODVERDIR) +ifdef need-modorder +targets-for-modules += $(obj)/modules.order +endif -__build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \ - $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \ - $(subdir-ym) $(always) - @: +targets += $(targets-for-builtin) $(targets-for-modules) # Linus' kernel sanity checking tool -ifneq ($(KBUILD_CHECKSRC),0) - ifeq ($(KBUILD_CHECKSRC),2) - quiet_cmd_force_checksrc = CHECK $< - cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ; - else - quiet_cmd_checksrc = CHECK $< - cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ; - endif +ifeq ($(KBUILD_CHECKSRC),1) + quiet_cmd_checksrc = CHECK $< + cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< +else ifeq ($(KBUILD_CHECKSRC),2) + quiet_cmd_force_checksrc = CHECK $< + cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< endif -# Do section mismatch analysis for each module/built-in.o -ifdef CONFIG_DEBUG_SECTION_MISMATCH - cmd_secanalysis = ; scripts/mod/modpost $@ +ifneq ($(KBUILD_EXTRA_WARN),) + cmd_checkdoc = PYTHONDONTWRITEBYTECODE=1 $(PYTHON3) $(KERNELDOC) -none $(KDOCFLAGS) \ + $(if $(findstring 2, $(KBUILD_EXTRA_WARN)), -Wall) \ + $< endif # Compile C sources (.c) # --------------------------------------------------------------------------- -# Default is built-in, unless we know otherwise -modkern_cflags = \ - $(if $(part-of-module), \ - $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \ - $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL)) -quiet_modtag := $(empty) $(empty) - -$(real-objs-m) : part-of-module := y -$(real-objs-m:.o=.i) : part-of-module := y -$(real-objs-m:.o=.s) : part-of-module := y -$(real-objs-m:.o=.lst): part-of-module := y - -$(real-objs-m) : quiet_modtag := [M] -$(real-objs-m:.o=.i) : quiet_modtag := [M] -$(real-objs-m:.o=.s) : quiet_modtag := [M] -$(real-objs-m:.o=.lst): quiet_modtag := [M] - -$(obj-m) : quiet_modtag := [M] - -# Default for not multi-part modules -modname = $(basetarget) - -$(multi-objs-m) : modname = $(modname-multi) -$(multi-objs-m:.o=.i) : modname = $(modname-multi) -$(multi-objs-m:.o=.s) : modname = $(modname-multi) -$(multi-objs-m:.o=.lst) : modname = $(modname-multi) -$(multi-objs-y) : modname = $(modname-multi) -$(multi-objs-y:.o=.i) : modname = $(modname-multi) -$(multi-objs-y:.o=.s) : modname = $(modname-multi) -$(multi-objs-y:.o=.lst) : modname = $(modname-multi) - quiet_cmd_cc_s_c = CC $(quiet_modtag) $@ -cmd_cc_s_c = $(CC) $(c_flags) -fverbose-asm -S -o $@ $< + cmd_cc_s_c = $(CC) $(filter-out $(DEBUG_CFLAGS) $(CC_FLAGS_LTO), $(c_flags)) -fverbose-asm -S -o $@ $< -$(obj)/%.s: $(src)/%.c FORCE +$(obj)/%.s: $(obj)/%.c FORCE $(call if_changed_dep,cc_s_c) -quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@ -cmd_cc_i_c = $(CPP) $(c_flags) -o $@ $< +quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@ +cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $< -$(obj)/%.i: $(src)/%.c FORCE - $(call if_changed_dep,cc_i_c) +$(obj)/%.i: $(obj)/%.c FORCE + $(call if_changed_dep,cpp_i_c) -cmd_gensymtypes = \ - $(CPP) -D__GENKSYMS__ $(c_flags) $< | \ - $(GENKSYMS) $(if $(1), -T $(2)) \ - $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \ - $(if $(KBUILD_PRESERVE),-p) \ - -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null)) +getexportsymbols = $(NM) $@ | sed -n 's/.* __export_symbol_\(.*\)/$(1)/p' -quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@ -cmd_cc_symtypes_c = \ - set -e; \ - $(call cmd_gensymtypes,true,$@) >/dev/null; \ - test -s $@ || rm -f $@ +gendwarfksyms = $(objtree)/scripts/gendwarfksyms/gendwarfksyms \ + $(if $(KBUILD_SYMTYPES), --symtypes $(@:.o=.symtypes)) \ + $(if $(KBUILD_GENDWARFKSYMS_STABLE), --stable) -$(obj)/%.symtypes : $(src)/%.c FORCE - $(call cmd,cc_symtypes_c) +genksyms = $(objtree)/scripts/genksyms/genksyms \ + $(if $(KBUILD_SYMTYPES), -T $(@:.o=.symtypes)) \ + $(if $(KBUILD_PRESERVE), -p) \ + $(addprefix -r , $(wildcard $(@:.o=.symref))) + +# These mirror gensymtypes_S and co below, keep them in synch. +ifdef CONFIG_GENDWARFKSYMS +cmd_gensymtypes_c = $(if $(skip_gendwarfksyms),, \ + $(call getexportsymbols,\1) | $(gendwarfksyms) $@) +else +cmd_gensymtypes_c = $(CPP) -D__GENKSYMS__ $(c_flags) $< | $(genksyms) +endif # CONFIG_GENDWARFKSYMS + +# LLVM assembly +# Generate .ll files from .c +quiet_cmd_cc_ll_c = CC $(quiet_modtag) $@ + cmd_cc_ll_c = $(CC) $(c_flags) -emit-llvm -S -fno-discard-value-names -o $@ $< + +$(obj)/%.ll: $(obj)/%.c FORCE + $(call if_changed_dep,cc_ll_c) # C (.c) files # The C file is compiled and updated dependency information is generated. # (See cmd_cc_o_c + relevant part of rule_cc_o_c) -quiet_cmd_cc_o_c = CC $(quiet_modtag) $@ +is-single-obj-m = $(and $(part-of-module),$(filter $@, $(obj-m)),y) -ifndef CONFIG_MODVERSIONS -cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< - -else +ifdef CONFIG_MODVERSIONS # When module versioning is enabled the following steps are executed: -# o compile a .tmp_<file>.o from <file>.c -# o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does -# not export symbols, we just rename .tmp_<file>.o to <file>.o and -# are done. +# o compile a <file>.o from <file>.c +# o if <file>.o doesn't contain a __export_symbol_*, i.e. does +# not export symbols, it's done. # o otherwise, we calculate symbol versions using the good old -# genksyms on the preprocessed source and postprocess them in a way -# that they are usable as a linker script -# o generate <file>.o from .tmp_<file>.o using the linker to -# replace the unresolved symbols __crc_exported_symbol with -# the actual value of the checksum generated by genksyms - -cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $< -cmd_modversions = \ - if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \ - $(call cmd_gensymtypes,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \ - > $(@D)/.tmp_$(@F:.o=.ver); \ - \ - $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \ - -T $(@D)/.tmp_$(@F:.o=.ver); \ - rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \ - else \ - mv -f $(@D)/.tmp_$(@F) $@; \ - fi; +# genksyms on the preprocessed source and dump them into the .cmd file. +# o modpost will extract versions from that file and create *.c files that will +# be compiled and linked to the kernel and/or modules. + +gen_symversions = \ + if $(NM) $@ 2>/dev/null | grep -q ' __export_symbol_'; then \ + $(cmd_gensymtypes_$1) >> $(dot-target).cmd; \ + fi + +cmd_gen_symversions_c = $(call gen_symversions,c) + endif -ifdef CONFIG_FTRACE_MCOUNT_RECORD +ifdef CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT +# compiler will not generate __mcount_loc use recordmcount or recordmcount.pl ifdef BUILD_C_RECORDMCOUNT ifeq ("$(origin RECORDMCOUNT_WARN)", "command line") RECORDMCOUNT_FLAGS = -w endif # Due to recursion, we must skip empty.o. # The empty.o file is created in the make process in order to determine -# the target endianness and word size. It is made before all other C -# files, including recordmcount. +# the target endianness and word size. It is made before all other C +# files, including recordmcount. sub_cmd_record_mcount = \ if [ $(@) != "scripts/mod/empty.o" ]; then \ $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \ @@ -277,79 +256,187 @@ sub_cmd_record_mcount = \ recordmcount_source := $(srctree)/scripts/recordmcount.c \ $(srctree)/scripts/recordmcount.h else -sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \ +sub_cmd_record_mcount = perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \ "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \ "$(if $(CONFIG_64BIT),64,32)" \ - "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \ - "$(LD)" "$(NM)" "$(RM)" "$(MV)" \ + "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS)" \ + "$(LD) $(KBUILD_LDFLAGS)" "$(NM)" "$(RM)" "$(MV)" \ "$(if $(part-of-module),1,0)" "$(@)"; recordmcount_source := $(srctree)/scripts/recordmcount.pl -endif -cmd_record_mcount = \ - if [ "$(findstring -pg,$(_c_flags))" = "-pg" ]; then \ - $(sub_cmd_record_mcount) \ - fi; +endif # BUILD_C_RECORDMCOUNT +cmd_record_mcount = $(if $(findstring $(strip $(CC_FLAGS_FTRACE)),$(_c_flags)), \ + $(sub_cmd_record_mcount)) +endif # CONFIG_FTRACE_MCOUNT_USE_RECORDMCOUNT + +# 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory +# 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file +# 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file + +is-standard-object = $(if $(filter-out y%, $(OBJECT_FILES_NON_STANDARD_$(target-stem).o)$(OBJECT_FILES_NON_STANDARD)n),$(is-kernel-object)) + +ifdef CONFIG_OBJTOOL +$(obj)/%.o: private objtool-enabled = $(if $(is-standard-object),$(if $(delay-objtool),$(is-single-obj-m),y)) endif -define rule_cc_o_c - $(call echo-cmd,checksrc) $(cmd_checksrc) \ - $(call echo-cmd,cc_o_c) $(cmd_cc_o_c); \ - $(cmd_modversions) \ - $(call echo-cmd,record_mcount) \ - $(cmd_record_mcount) \ - scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' > \ - $(dot-target).tmp; \ - rm -f $(depfile); \ - mv -f $(dot-target).tmp $(dot-target).cmd -endef +ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) +cmd_warn_shared_object = $(if $(word 2, $(modname-multi)),$(warning $(kbuild-file): $*.o is added to multiple modules: $(modname-multi))) +endif # Built-in and composite module parts -$(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE - $(call cmd,force_checksrc) +$(obj)/%.o: $(obj)/%.c $(recordmcount_source) FORCE $(call if_changed_rule,cc_o_c) + $(call cmd,force_checksrc) -# Single-part modules are special since we need to mark them in $(MODVERDIR) +# To make this rule robust against "Argument list too long" error, +# ensure to add $(obj)/ prefix by a shell command. +cmd_mod = printf '%s\n' $(call real-search, $*.o, .o, -objs -y -m) | \ + $(AWK) '!x[$$0]++ { print("$(obj)/"$$0) }' > $@ -$(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE - $(call cmd,force_checksrc) - $(call if_changed_rule,cc_o_c) - @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod) +$(obj)/%.mod: FORCE + $(call if_changed,mod) quiet_cmd_cc_lst_c = MKLST $@ cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \ $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \ System.map $(OBJDUMP) > $@ -$(obj)/%.lst: $(src)/%.c FORCE +$(obj)/%.lst: $(obj)/%.c FORCE $(call if_changed_dep,cc_lst_c) +# Compile Rust sources (.rs) +# --------------------------------------------------------------------------- + +# The features in this list are the ones allowed for non-`rust/` code. +# +# - Stable since Rust 1.81.0: `feature(lint_reasons)`. +# - Stable since Rust 1.82.0: `feature(asm_const)`, +# `feature(offset_of_nested)`, `feature(raw_ref_op)`. +# - Stable since Rust 1.87.0: `feature(asm_goto)`. +# - Expected to become stable: `feature(arbitrary_self_types)`. +# - To be determined: `feature(used_with_arg)`. +# +# Please see https://github.com/Rust-for-Linux/linux/issues/2 for details on +# the unstable features in use. +rust_allowed_features := asm_const,asm_goto,arbitrary_self_types,lint_reasons,offset_of_nested,raw_ref_op,used_with_arg + +# `--out-dir` is required to avoid temporaries being created by `rustc` in the +# current working directory, which may be not accessible in the out-of-tree +# modules case. +rust_common_cmd = \ + OBJTREE=$(abspath $(objtree)) \ + RUST_MODFILE=$(modfile) $(RUSTC_OR_CLIPPY) $(rust_flags) \ + -Zallow-features=$(rust_allowed_features) \ + -Zcrate-attr=no_std \ + -Zcrate-attr='feature($(rust_allowed_features))' \ + -Zunstable-options --extern pin_init --extern kernel \ + --crate-type rlib -L $(objtree)/rust/ \ + --crate-name $(basename $(notdir $@)) \ + --sysroot=/dev/null \ + --out-dir $(dir $@) --emit=dep-info=$(depfile) + +# `--emit=obj`, `--emit=asm` and `--emit=llvm-ir` imply a single codegen unit +# will be used. We explicitly request `-Ccodegen-units=1` in any case, and +# the compiler shows a warning if it is not 1. However, if we ever stop +# requesting it explicitly and we start using some other `--emit` that does not +# imply it (and for which codegen is performed), then we would be out of sync, +# i.e. the outputs we would get for the different single targets (e.g. `.ll`) +# would not match each other. + +quiet_cmd_rustc_o_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ + cmd_rustc_o_rs = $(rust_common_cmd) --emit=obj=$@ $< $(cmd_objtool) + +define rule_rustc_o_rs + $(call cmd_and_fixdep,rustc_o_rs) + $(call cmd,gen_objtooldep) +endef + +$(obj)/%.o: $(obj)/%.rs FORCE + +$(call if_changed_rule,rustc_o_rs) + +quiet_cmd_rustc_rsi_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ + cmd_rustc_rsi_rs = \ + $(rust_common_cmd) -Zunpretty=expanded $< >$@; \ + command -v $(RUSTFMT) >/dev/null && $(RUSTFMT) $@ + +$(obj)/%.rsi: $(obj)/%.rs FORCE + +$(call if_changed_dep,rustc_rsi_rs) + +quiet_cmd_rustc_s_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ + cmd_rustc_s_rs = $(rust_common_cmd) --emit=asm=$@ $< + +$(obj)/%.s: $(obj)/%.rs FORCE + +$(call if_changed_dep,rustc_s_rs) + +quiet_cmd_rustc_ll_rs = $(RUSTC_OR_CLIPPY_QUIET) $(quiet_modtag) $@ + cmd_rustc_ll_rs = $(rust_common_cmd) --emit=llvm-ir=$@ $< + +$(obj)/%.ll: $(obj)/%.rs FORCE + +$(call if_changed_dep,rustc_ll_rs) + +quiet_cmd_rustc_rs_rs_S = RSCPP $(quiet_modtag) $@ + cmd_rustc_rs_rs_S = $(CPP) $(c_flags) -xc -C -P $< | sed '1,/^\/\/ Cut here.$$/d' >$@ + +$(obj)/%.rs: $(obj)/%.rs.S FORCE + +$(call if_changed_dep,rustc_rs_rs_S) + # Compile assembler sources (.S) # --------------------------------------------------------------------------- -modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL) +# .S file exports must have their C prototypes defined in asm/asm-prototypes.h +# or a file that it includes, in order to get versioned symbols. We build a +# dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from +# the .S file (with trailing ';'), and run genksyms on that, to extract vers. +# +# This is convoluted. The .S file must first be preprocessed to run guards and +# expand names, then the resulting exports must be constructed into plain +# EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed +# to make the genksyms input or compiled into an object for gendwarfksyms. +# +# These mirror gensymtypes_c and co above, keep them in synch. +getasmexports = \ + { echo "\#include <linux/kernel.h>" ; \ + echo "\#include <linux/string.h>" ; \ + echo "\#include <asm/asm-prototypes.h>" ; \ + $(call getexportsymbols,EXPORT_SYMBOL(\1);) ; } + +ifdef CONFIG_GENDWARFKSYMS +cmd_gensymtypes_S = \ + $(getasmexports) | \ + $(CC) $(c_flags) -c -o $(@:.o=.gendwarfksyms.o) -xc -; \ + $(call getexportsymbols,\1) | \ + $(gendwarfksyms) $(@:.o=.gendwarfksyms.o) +else +cmd_gensymtypes_S = \ + $(getasmexports) | \ + $(CPP) -D__GENKSYMS__ $(c_flags) -xc - | $(genksyms) +endif # CONFIG_GENDWARFKSYMS -$(real-objs-m) : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE) -$(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE) +quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@ +cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $< -quiet_cmd_as_s_S = CPP $(quiet_modtag) $@ -cmd_as_s_S = $(CPP) $(a_flags) -o $@ $< +$(obj)/%.s: $(obj)/%.S FORCE + $(call if_changed_dep,cpp_s_S) -$(obj)/%.s: $(src)/%.S FORCE - $(call if_changed_dep,as_s_S) +ifdef CONFIG_ASM_MODVERSIONS -quiet_cmd_as_o_S = AS $(quiet_modtag) $@ -cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< +# versioning matches the C process described above, with difference that +# we parse asm-prototypes.h C header to get function definitions. -$(obj)/%.o: $(src)/%.S FORCE - $(call if_changed_dep,as_o_S) +cmd_gen_symversions_S = $(call gen_symversions,S) -targets += $(real-objs-y) $(real-objs-m) $(lib-y) -targets += $(extra-y) $(MAKECMDGOALS) $(always) +endif + +$(obj)/%.o: $(obj)/%.S FORCE + $(call if_changed_rule,as_o_S) + +targets += $(filter-out $(subdir-builtin), $(real-obj-y)) +targets += $(filter-out $(subdir-modorder), $(real-obj-m)) +targets += $(lib-y) $(always-y) # Linker scripts preprocessor (.lds.S -> .lds) # --------------------------------------------------------------------------- quiet_cmd_cpp_lds_S = LDS $@ - cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \ + cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -U$(ARCH) \ -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $< $(obj)/%.lds: $(src)/%.lds.S FORCE @@ -357,123 +444,146 @@ $(obj)/%.lds: $(src)/%.lds.S FORCE # ASN.1 grammar # --------------------------------------------------------------------------- -quiet_cmd_asn1_compiler = ASN.1 $@ +quiet_cmd_asn1_compiler = ASN.1 $(basename $@).[ch] cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \ - $(subst .h,.c,$@) $(subst .c,.h,$@) - -.PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h + $(basename $@).c $(basename $@).h -$(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler +$(obj)/%.asn1.c $(obj)/%.asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler $(call cmd,asn1_compiler) # Build the compiled-in targets # --------------------------------------------------------------------------- # To build objects in subdirs, we need to descend into the directories -$(sort $(subdir-obj-y)): $(subdir-ym) ; +$(subdir-builtin): $(obj)/%/built-in.a: $(obj)/% ; +$(subdir-modorder): $(obj)/%/modules.order: $(obj)/% ; # -# Rule to compile a set of .o files into one .o file +# Rule to compile a set of .o files into one .a file (without symbol table) # -ifdef builtin-target -quiet_cmd_link_o_target = LD $@ -# If the list of objects to link is empty, just create an empty built-in.o -cmd_link_o_target = $(if $(strip $(obj-y)),\ - $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \ - $(cmd_secanalysis),\ - rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@) +# To make this rule robust against "Argument list too long" error, +# remove $(obj)/ prefix, and restore it by a shell command. -$(builtin-target): $(obj-y) FORCE - $(call if_changed,link_o_target) +quiet_cmd_ar_builtin = AR $@ + cmd_ar_builtin = rm -f $@; \ + $(if $(real-prereqs), printf "$(obj)/%s " $(patsubst $(obj)/%,%,$(real-prereqs)) | xargs) \ + $(AR) cDPrST $@ -targets += $(builtin-target) -endif # builtin-target +$(obj)/built-in.a: $(real-obj-y) FORCE + $(call if_changed,ar_builtin) -# -# Rule to create modules.order file -# -# Create commands to either record .ko file or cat modules.order from -# a subdirectory -modorder-cmds = \ - $(foreach m, $(modorder), \ - $(if $(filter %/modules.order, $m), \ - cat $m;, echo kernel/$m;)) +# This is a list of build artifacts from the current Makefile and its +# sub-directories. The timestamp should be updated when any of the member files. -$(modorder-target): $(subdir-ym) FORCE - $(Q)(cat /dev/null; $(modorder-cmds)) > $@ +cmd_gen_order = { $(foreach m, $(real-prereqs), \ + $(if $(filter %/$(notdir $@), $m), cat $m, echo $m);) :; } \ + > $@ + +$(obj)/modules.order: $(obj-m) FORCE + $(call if_changed,gen_order) # -# Rule to compile a set of .o files into one .a file +# Rule to compile a set of .o files into one .a file (with symbol table) # -ifdef lib-target -quiet_cmd_link_l_target = AR $@ -cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y) -$(lib-target): $(lib-y) FORCE - $(call if_changed,link_l_target) +$(obj)/lib.a: $(lib-y) FORCE + $(call if_changed,ar) + +quiet_cmd_ld_multi_m = LD [M] $@ + cmd_ld_multi_m = $(LD) $(ld_flags) -r -o $@ @$< $(cmd_objtool) + +define rule_ld_multi_m + $(call cmd_and_savecmd,ld_multi_m) + $(call cmd,gen_objtooldep) +endef + +$(multi-obj-m): private objtool-enabled := $(delay-objtool) +$(multi-obj-m): private part-of-module := y +$(multi-obj-m): %.o: %.mod FORCE + $(call if_changed_rule,ld_multi_m) +$(call multi_depend, $(multi-obj-m), .o, -objs -y -m) + +# Add intermediate targets: +# When building objects with specific suffix patterns, add intermediate +# targets that the final targets are derived from. +intermediate_targets = $(foreach sfx, $(2), \ + $(patsubst %$(strip $(1)),%$(sfx), \ + $(filter %$(strip $(1)), $(targets)))) +# %.asn1.o <- %.asn1.[ch] <- %.asn1 +targets += $(call intermediate_targets, .asn1.o, .asn1.c .asn1.h) + +# Include additional build rules when necessary +# --------------------------------------------------------------------------- -targets += $(lib-target) +# $(sort ...) is used here to remove duplicated words and excessive spaces. +hostprogs := $(sort $(hostprogs)) +ifneq ($(hostprogs),) +include $(srctree)/scripts/Makefile.host endif -# -# Rule to link composite objects -# -# Composite objects are specified in kbuild makefile as follows: -# <composite-object>-objs := <list of .o files> -# or -# <composite-object>-y := <list of .o files> -link_multi_deps = \ -$(filter $(addprefix $(obj)/, \ -$($(subst $(obj)/,,$(@:.o=-objs))) \ -$($(subst $(obj)/,,$(@:.o=-y)))), $^) - -quiet_cmd_link_multi-y = LD $@ -cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis) - -quiet_cmd_link_multi-m = LD [M] $@ -cmd_link_multi-m = $(cmd_link_multi-y) - -# We would rather have a list of rules like -# foo.o: $(foo-objs) -# but that's not so easy, so we rather make all composite objects depend -# on the set of all their parts -$(multi-used-y) : %.o: $(multi-objs-y) FORCE - $(call if_changed,link_multi-y) - -$(multi-used-m) : %.o: $(multi-objs-m) FORCE - $(call if_changed,link_multi-m) - @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod) - -targets += $(multi-used-y) $(multi-used-m) +# $(sort ...) is used here to remove duplicated words and excessive spaces. +userprogs := $(sort $(userprogs)) +ifneq ($(userprogs),) +include $(srctree)/scripts/Makefile.userprogs +endif + +ifneq ($(need-dtbslist)$(dtb-y)$(dtb-)$(filter %.dtb %.dtb.o %.dtbo.o,$(targets)),) +include $(srctree)/scripts/Makefile.dtbs +endif +# Build +# --------------------------------------------------------------------------- + +$(obj)/: $(if $(KBUILD_BUILTIN), $(targets-for-builtin)) \ + $(if $(KBUILD_MODULES), $(targets-for-modules)) \ + $(subdir-ym) $(always-y) + @: + +# Single targets +# --------------------------------------------------------------------------- + +single-subdirs := $(foreach d, $(subdir-ym), $(if $(filter $d/%, $(MAKECMDGOALS)), $d)) +single-subdir-goals := $(filter $(addsuffix /%, $(single-subdirs)), $(MAKECMDGOALS)) + +$(single-subdir-goals): $(single-subdirs) + @: # Descending # --------------------------------------------------------------------------- PHONY += $(subdir-ym) $(subdir-ym): - $(Q)$(MAKE) $(build)=$@ + $(Q)$(MAKE) $(build)=$@ \ + need-builtin=$(if $(filter $@/built-in.a, $(subdir-builtin)),1) \ + need-modorder=$(if $(filter $@/modules.order, $(subdir-modorder)),1) \ + $(filter $@/%, $(single-subdir-goals)) -# Add FORCE to the prequisites of a target to force it to be always rebuilt. +# Add FORCE to the prerequisites of a target to force it to be always rebuilt. # --------------------------------------------------------------------------- PHONY += FORCE FORCE: +targets += $(filter-out $(single-subdir-goals), $(MAKECMDGOALS)) +targets := $(filter-out $(PHONY), $(targets)) + # Read all saved command lines and dependencies for the $(targets) we # may be building above, using $(if_changed{,_dep}). As an # optimization, we don't need to read them if the target does not # exist, we will rebuild anyway in that case. -targets := $(wildcard $(sort $(targets))) -cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd)) +existing-targets := $(wildcard $(sort $(targets))) -ifneq ($(cmd_files),) - include $(cmd_files) -endif +-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) -# Declare the contents of the .PHONY variable as phony. We keep that -# information in a variable se we can use it in if_changed and friends. +# Create directories for object files if they do not exist +obj-dirs := $(sort $(patsubst %/,%, $(dir $(targets)))) +# If targets exist, their directories apparently exist. Skip mkdir. +existing-dirs := $(sort $(patsubst %/,%, $(dir $(existing-targets)))) +obj-dirs := $(strip $(filter-out $(existing-dirs), $(obj-dirs))) +ifneq ($(obj-dirs),) +$(shell mkdir -p $(obj-dirs)) +endif .PHONY: $(PHONY) |