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Diffstat (limited to 'scripts/Makefile.modpost')
| -rw-r--r-- | scripts/Makefile.modpost | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost new file mode 100644 index 00000000..08dce14f --- /dev/null +++ b/scripts/Makefile.modpost @@ -0,0 +1,153 @@ +# =========================================================================== +# Module versions +# =========================================================================== +# +# Stage one of module building created the following: +# a) The individual .o files used for the module +# b) A <module>.o file which is the .o files above linked together +# c) A <module>.mod file in $(MODVERDIR)/, listing the name of the +# the preliminary <module>.o file, plus all .o files + +# Stage 2 is handled by this file and does the following +# 1) Find all modules from the files listed in $(MODVERDIR)/ +# 2) modpost is then used to +# 3) create one <module>.mod.c file pr. module +# 4) create one Module.symvers file with CRC for all exported symbols +# 5) compile all <module>.mod.c files +# 6) final link of the module to a <module.ko> file + +# Step 3 is used to place certain information in the module's ELF +# section, including information such as: +# Version magic (see include/linux/vermagic.h for full details) +# - Kernel release +# - SMP is CONFIG_SMP +# - PREEMPT is CONFIG_PREEMPT +# - GCC Version +# Module info +# - Module version (MODULE_VERSION) +# - Module alias'es (MODULE_ALIAS) +# - Module license (MODULE_LICENSE) +# - See include/linux/module.h for more details + +# Step 4 is solely used to allow module versioning in external modules, +# where the CRC of each module is retrieved from the Module.symvers file. + +# KBUILD_MODPOST_WARN can be set to avoid error out in case of undefined +# symbols in the final module linking stage +# KBUILD_MODPOST_NOFINAL can be set to skip the final link of modules. +# This is solely useful to speed up test compiles +PHONY := _modpost +_modpost: __modpost + +include include/config/auto.conf +include scripts/Kbuild.include + +# When building external modules load the Kbuild file to retrieve EXTRA_SYMBOLS info +ifneq ($(KBUILD_EXTMOD),) + +# set src + obj - they may be used when building the .mod.c file +obj := $(KBUILD_EXTMOD) +src := $(obj) + +# Include the module's Makefile to find KBUILD_EXTRA_SYMBOLS +include $(if $(wildcard $(KBUILD_EXTMOD)/Kbuild), \ + $(KBUILD_EXTMOD)/Kbuild, $(KBUILD_EXTMOD)/Makefile) +endif + +include scripts/Makefile.lib + +kernelsymfile := $(objtree)/Module.symvers +modulesymfile := $(firstword $(KBUILD_EXTMOD))/Module.symvers + +# Step 1), find all modules listed in $(MODVERDIR)/ +__modules := $(sort $(shell grep -h '\.ko' /dev/null $(wildcard $(MODVERDIR)/*.mod))) +modules := $(patsubst %.o,%.ko, $(wildcard $(__modules:.ko=.o))) + +# Stop after building .o files if NOFINAL is set. Makes compile tests quicker +_modpost: $(if $(KBUILD_MODPOST_NOFINAL), $(modules:.ko:.o),$(modules)) + +ifneq ($(KBUILD_BUILDHOST),$(ARCH)) + cross_build := 1 +endif + +# Step 2), invoke modpost +# Includes step 3,4 +modpost = scripts/mod/modpost \ + $(if $(CONFIG_MODVERSIONS),-m) \ + $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a,) \ + $(if $(KBUILD_EXTMOD),-i,-o) $(kernelsymfile) \ + $(if $(KBUILD_EXTMOD),-I $(modulesymfile)) \ + $(if $(KBUILD_EXTRA_SYMBOLS), $(patsubst %, -e %,$(KBUILD_EXTRA_SYMBOLS))) \ + $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ + $(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S) \ + $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w) \ + $(if $(cross_build),-c) + +quiet_cmd_modpost = MODPOST $(words $(filter-out vmlinux FORCE, $^)) modules + cmd_modpost = $(modpost) -s + +PHONY += __modpost +__modpost: $(modules:.ko=.o) FORCE + $(call cmd,modpost) $(wildcard vmlinux) $(filter-out FORCE,$^) + +quiet_cmd_kernel-mod = MODPOST $@ + cmd_kernel-mod = $(modpost) $@ + +vmlinux.o: FORCE + $(call cmd,kernel-mod) + +# Declare generated files as targets for modpost +$(symverfile): __modpost ; +$(modules:.ko=.mod.c): __modpost ; + + +# Step 5), compile all *.mod.c files + +# modname is set to make c_flags define KBUILD_MODNAME +modname = $(notdir $(@:.mod.o=)) + +quiet_cmd_cc_o_c = CC $@ + cmd_cc_o_c = $(CC) $(c_flags) $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE) \ + -c -o $@ $< + +$(modules:.ko=.mod.o): %.mod.o: %.mod.c FORCE + $(call if_changed_dep,cc_o_c) + +targets += $(modules:.ko=.mod.o) + +# Step 6), final link of the modules +quiet_cmd_ld_ko_o = LD [M] $@ + cmd_ld_ko_o = $(LD) -r $(LDFLAGS) \ + $(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \ + -o $@ $(filter-out FORCE,$^) + +$(modules): %.ko :%.o %.mod.o FORCE + $(call if_changed,ld_ko_o) + +targets += $(modules) + + +# Add FORCE to the prequisites of a target to force it to be always rebuilt. +# --------------------------------------------------------------------------- + +PHONY += FORCE + +FORCE: + +# 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 $(f)).cmd)) + +ifneq ($(cmd_files),) + include $(cmd_files) +endif + + +# 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. + +.PHONY: $(PHONY) |