scripts/Makefile.build

   1 # ==========================================================================
   2 # Building
   3 # ==========================================================================
   4
   5 src := $(obj)
   6
   7 PHONY := __build
   8 __build:
   9
  10 # Init all relevant variables used in kbuild files so
  11 # 1) they have correct type
  12 # 2) they do not inherit any value from the environment
  13 obj-y :=
  14 obj-m :=
  15 lib-y :=
  16 lib-m :=
  17 always :=
  18 targets :=
  19 subdir-y :=
  20 subdir-m :=
  21 EXTRA_AFLAGS   :=
  22 EXTRA_CFLAGS   :=
  23 EXTRA_CPPFLAGS :=
  24 EXTRA_LDFLAGS  :=
  25 asflags-y  :=
  26 ccflags-y  :=
  27 cppflags-y :=
  28 ldflags-y  :=
  29
  30 subdir-asflags-y :=
  31 subdir-ccflags-y :=
  32
  33 # Read auto.conf if it exists, otherwise ignore
  34 -include include/config/auto.conf
  35
  36 include scripts/Kbuild.include
  37
  38 # For backward compatibility check that these variables do not change
  39 save-cflags := $(CFLAGS)
  40
  41 # The filename Kbuild has precedence over Makefile
  42 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
  43 kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
  44 include $(kbuild-file)
  45
  46 # If the save-* variables changed error out
  47 ifeq ($(KBUILD_NOPEDANTIC),)
  48         ifneq ("$(save-cflags)","$(CFLAGS)")
  49                 $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
  50         endif
  51 endif
  52
  53 include scripts/Makefile.lib
  54
  55 ifdef host-progs
  56 ifneq ($(hostprogs-y),$(host-progs))
  57 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
  58 hostprogs-y += $(host-progs)
  59 endif
  60 endif
  61
  62 # Do not include host rules unless needed
  63 ifneq ($(hostprogs-y)$(hostprogs-m),)
  64 include scripts/Makefile.host
  65 endif
  66
  67 ifneq ($(KBUILD_SRC),)
  68 # Create output directory if not already present
  69 _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
  70
  71 # Create directories for object files if directory does not exist
  72 # Needed when obj-y := dir/file.o syntax is used
  73 _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
  74 endif
  75
  76 ifndef obj
  77 $(warning kbuild: Makefile.build is included improperly)
  78 endif
  79
  80 # ===========================================================================
  81
  82 ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
  83 lib-target := $(obj)/lib.a
  84 endif
  85
  86 ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
  87 builtin-target := $(obj)/built-in.o
  88 endif
  89
  90 modorder-target := $(obj)/modules.order
  91
  92 # We keep a list of all modules in $(MODVERDIR)
  93
  94 __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
  95          $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
  96          $(subdir-ym) $(always)
  97         @:
  98
  99 # Linus' kernel sanity checking tool
 100 ifneq ($(KBUILD_CHECKSRC),0)
 101   ifeq ($(KBUILD_CHECKSRC),2)
 102     quiet_cmd_force_checksrc = CHECK   $<
 103           cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
 104   else
 105       quiet_cmd_checksrc     = CHECK   $<
 106             cmd_checksrc     = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
 107   endif
 108 endif
 109
 110 # Do section mismatch analysis for each module/built-in.o
 111 ifdef CONFIG_DEBUG_SECTION_MISMATCH
 112   cmd_secanalysis = ; scripts/mod/modpost $@
 113 endif
 114
 115 # Compile C sources (.c)
 116 # ---------------------------------------------------------------------------
 117
 118 # Default is built-in, unless we know otherwise
 119 modkern_cflags =                                          \
 120         $(if $(part-of-module),                           \
 121                 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 122                 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
 123 quiet_modtag := $(empty)   $(empty)
 124
 125 $(real-objs-m)        : part-of-module := y
 126 $(real-objs-m:.o=.i)  : part-of-module := y
 127 $(real-objs-m:.o=.s)  : part-of-module := y
 128 $(real-objs-m:.o=.lst): part-of-module := y
 129
 130 $(real-objs-m)        : quiet_modtag := [M]
 131 $(real-objs-m:.o=.i)  : quiet_modtag := [M]
 132 $(real-objs-m:.o=.s)  : quiet_modtag := [M]
 133 $(real-objs-m:.o=.lst): quiet_modtag := [M]
 134
 135 $(obj-m)              : quiet_modtag := [M]
 136
 137 # Default for not multi-part modules
 138 modname = $(basetarget)
 139
 140 $(multi-objs-m)         : modname = $(modname-multi)
 141 $(multi-objs-m:.o=.i)   : modname = $(modname-multi)
 142 $(multi-objs-m:.o=.s)   : modname = $(modname-multi)
 143 $(multi-objs-m:.o=.lst) : modname = $(modname-multi)
 144 $(multi-objs-y)         : modname = $(modname-multi)
 145 $(multi-objs-y:.o=.i)   : modname = $(modname-multi)
 146 $(multi-objs-y:.o=.s)   : modname = $(modname-multi)
 147 $(multi-objs-y:.o=.lst) : modname = $(modname-multi)
 148
 149 quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
 150 cmd_cc_s_c       = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
 151
 152 $(obj)/%.s: $(src)/%.c FORCE
 153         $(call if_changed_dep,cc_s_c)
 154
 155 quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@
 156 cmd_cc_i_c       = $(CPP) $(c_flags)   -o $@ $<
 157
 158 $(obj)/%.i: $(src)/%.c FORCE
 159         $(call if_changed_dep,cc_i_c)
 160
 161 # These mirror gensymtypes_S and co below, keep them in synch.
 162 cmd_gensymtypes_c =                                                         \
 163     $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
 164     $(GENKSYMS) $(if $(1), -T $(2))                                         \
 165      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
 166      $(if $(KBUILD_PRESERVE),-p)                                            \
 167      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 168
 169 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
 170 cmd_cc_symtypes_c =                                                         \
 171     set -e;                                                                 \
 172     $(call cmd_gensymtypes_c,true,$@) >/dev/null;                           \
 173     test -s $@ || rm -f $@
 174
 175 $(obj)/%.symtypes : $(src)/%.c FORCE
 176         $(call cmd,cc_symtypes_c)
 177
 178 # C (.c) files
 179 # The C file is compiled and updated dependency information is generated.
 180 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
 181
 182 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
 183
 184 ifndef CONFIG_MODVERSIONS
 185 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 186
 187 else
 188 # When module versioning is enabled the following steps are executed:
 189 # o compile a .tmp_<file>.o from <file>.c
 190 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
 191 #   not export symbols, we just rename .tmp_<file>.o to <file>.o and
 192 #   are done.
 193 # o otherwise, we calculate symbol versions using the good old
 194 #   genksyms on the preprocessed source and postprocess them in a way
 195 #   that they are usable as a linker script
 196 # o generate <file>.o from .tmp_<file>.o using the linker to
 197 #   replace the unresolved symbols __crc_exported_symbol with
 198 #   the actual value of the checksum generated by genksyms
 199
 200 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
 201
 202 cmd_modversions_c =                                                             \
 203         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 204                 $(call cmd_gensymtypes_c,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
 205                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 206                                                                                 \
 207                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 208                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 209                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 210         else                                                                    \
 211                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
 212         fi;
 213 endif
 214
 215 ifdef CONFIG_FTRACE_MCOUNT_RECORD
 216 ifdef BUILD_C_RECORDMCOUNT
 217 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
 218   RECORDMCOUNT_FLAGS = -w
 219 endif
 220 # Due to recursion, we must skip empty.o.
 221 # The empty.o file is created in the make process in order to determine
 222 #  the target endianness and word size. It is made before all other C
 223 #  files, including recordmcount.
 224 sub_cmd_record_mcount =                                 \
 225         if [ $(@) != "scripts/mod/empty.o" ]; then      \
 226                 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)";   \
 227         fi;
 228 recordmcount_source := $(srctree)/scripts/recordmcount.c \
 229                     $(srctree)/scripts/recordmcount.h
 230 else
 231 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
 232         "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
 233         "$(if $(CONFIG_64BIT),64,32)" \
 234         "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
 235         "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
 236         "$(if $(part-of-module),1,0)" "$(@)";
 237 recordmcount_source := $(srctree)/scripts/recordmcount.pl
 238 endif
 239 cmd_record_mcount =                                             \
 240         if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" =   \
 241              "$(CC_FLAGS_FTRACE)" ]; then                       \
 242                 $(sub_cmd_record_mcount)                        \
 243         fi;
 244 endif
 245
 246 define rule_cc_o_c
 247         $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
 248         $(call echo-cmd,cc_o_c) $(cmd_cc_o_c);                            \
 249         $(cmd_modversions_c)                                              \
 250         $(call echo-cmd,record_mcount)                                    \
 251         $(cmd_record_mcount)                                              \
 252         scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' >    \
 253                                                       $(dot-target).tmp;  \
 254         rm -f $(depfile);                                                 \
 255         mv -f $(dot-target).tmp $(dot-target).cmd
 256 endef
 257
 258 define rule_as_o_S
 259        $(call echo-cmd,as_o_S) $(cmd_as_o_S);                            \
 260        scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,as_o_S)' >    \
 261                                                      $(dot-target).tmp;  \
 262        $(cmd_modversions_S)                                              \
 263        rm -f $(depfile);                                                 \
 264        mv -f $(dot-target).tmp $(dot-target).cmd
 265 endef
 266
 267 # Built-in and composite module parts
 268 $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
 269         $(call cmd,force_checksrc)
 270         $(call if_changed_rule,cc_o_c)
 271
 272 # Single-part modules are special since we need to mark them in $(MODVERDIR)
 273
 274 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) FORCE
 275         $(call cmd,force_checksrc)
 276         $(call if_changed_rule,cc_o_c)
 277         @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod)
 278
 279 quiet_cmd_cc_lst_c = MKLST   $@
 280       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
 281                      $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
 282                                      System.map $(OBJDUMP) > $@
 283
 284 $(obj)/%.lst: $(src)/%.c FORCE
 285         $(call if_changed_dep,cc_lst_c)
 286
 287 # Compile assembler sources (.S)
 288 # ---------------------------------------------------------------------------
 289
 290 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
 291
 292 $(real-objs-m)      : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 293 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
 294
 295 # .S file exports must have their C prototypes defined in asm/asm-prototypes.h
 296 # or a file that it includes, in order to get versioned symbols. We build a
 297 # dummy C file that includes asm-prototypes and the EXPORT_SYMBOL lines from
 298 # the .S file (with trailing ';'), and run genksyms on that, to extract vers.
 299 #
 300 # This is convoluted. The .S file must first be preprocessed to run guards and
 301 # expand names, then the resulting exports must be constructed into plain
 302 # EXPORT_SYMBOL(symbol); to build our dummy C file, and that gets preprocessed
 303 # to make the genksyms input.
 304 #
 305 # These mirror gensymtypes_c and co above, keep them in synch.
 306 cmd_gensymtypes_S =                                                         \
 307     (echo "\#include <linux/kernel.h>" ;                                    \
 308      echo "\#include <asm/asm-prototypes.h>" ;                              \
 309     $(CPP) $(a_flags) $< |                                                  \
 310       grep "\<___EXPORT_SYMBOL\>" |                                          \
 311       sed 's/.*___EXPORT_SYMBOL[[:space:]]*\([a-zA-Z0-9_]*\)[[:space:]]*,.*/EXPORT_SYMBOL(\1);/' ) | \
 312     $(CPP) -D__GENKSYMS__ $(c_flags) -xc - |                                \
 313     $(GENKSYMS) $(if $(1), -T $(2))                                         \
 314      $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
 315      $(if $(KBUILD_PRESERVE),-p)                                            \
 316      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 317
 318 quiet_cmd_cc_symtypes_S = SYM $(quiet_modtag) $@
 319 cmd_cc_symtypes_S =                                                         \
 320     set -e;                                                                 \
 321     $(call cmd_gensymtypes_S,true,$@) >/dev/null;                           \
 322     test -s $@ || rm -f $@
 323
 324 $(obj)/%.symtypes : $(src)/%.S FORCE
 325         $(call cmd,cc_symtypes_S)
 326
 327 quiet_cmd_as_s_S = CPP $(quiet_modtag) $@
 328 cmd_as_s_S       = $(CPP) $(a_flags)   -o $@ $<
 329
 330 $(obj)/%.s: $(src)/%.S FORCE
 331         $(call if_changed_dep,as_s_S)
 332
 333 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
 334
 335 ifndef CONFIG_MODVERSIONS
 336 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
 337
 338 else
 339
 340 ASM_PROTOTYPES := $(wildcard $(srctree)/arch/$(SRCARCH)/include/asm/asm-prototypes.h)
 341
 342 ifeq ($(ASM_PROTOTYPES),)
 343 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
 344
 345 else
 346
 347 # versioning matches the C process described above, with difference that
 348 # we parse asm-prototypes.h C header to get function definitions.
 349
 350 cmd_as_o_S = $(CC) $(a_flags) -c -o $(@D)/.tmp_$(@F) $<
 351
 352 cmd_modversions_S =                                                             \
 353         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then             \
 354                 $(call cmd_gensymtypes_S,$(KBUILD_SYMTYPES),$(@:.o=.symtypes))  \
 355                     > $(@D)/.tmp_$(@F:.o=.ver);                                 \
 356                                                                                 \
 357                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)                      \
 358                         -T $(@D)/.tmp_$(@F:.o=.ver);                            \
 359                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);                \
 360         else                                                                    \
 361                 mv -f $(@D)/.tmp_$(@F) $@;                                      \
 362         fi;
 363 endif
 364 endif
 365
 366 $(obj)/%.o: $(src)/%.S FORCE
 367         $(call if_changed_rule,as_o_S)
 368
 369 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
 370 targets += $(extra-y) $(MAKECMDGOALS) $(always)
 371
 372 # Linker scripts preprocessor (.lds.S -> .lds)
 373 # ---------------------------------------------------------------------------
 374 quiet_cmd_cpp_lds_S = LDS     $@
 375       cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
 376                              -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
 377
 378 $(obj)/%.lds: $(src)/%.lds.S FORCE
 379         $(call if_changed_dep,cpp_lds_S)
 380
 381 # ASN.1 grammar
 382 # ---------------------------------------------------------------------------
 383 quiet_cmd_asn1_compiler = ASN.1   $@
 384       cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
 385                                 $(subst .h,.c,$@) $(subst .c,.h,$@)
 386
 387 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
 388
 389 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
 390         $(call cmd,asn1_compiler)
 391
 392 # Build the compiled-in targets
 393 # ---------------------------------------------------------------------------
 394
 395 # To build objects in subdirs, we need to descend into the directories
 396 $(sort $(subdir-obj-y)): $(subdir-ym) ;
 397
 398 #
 399 # Rule to compile a set of .o files into one .o file
 400 #
 401 ifdef builtin-target
 402 quiet_cmd_link_o_target = LD      $@
 403 # If the list of objects to link is empty, just create an empty built-in.o
 404 cmd_link_o_target = $(if $(strip $(obj-y)),\
 405                       $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \
 406                       $(cmd_secanalysis),\
 407                       rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@)
 408
 409 $(builtin-target): $(obj-y) FORCE
 410         $(call if_changed,link_o_target)
 411
 412 targets += $(builtin-target)
 413 endif # builtin-target
 414
 415 #
 416 # Rule to create modules.order file
 417 #
 418 # Create commands to either record .ko file or cat modules.order from
 419 # a subdirectory
 420 modorder-cmds =                                         \
 421         $(foreach m, $(modorder),                       \
 422                 $(if $(filter %/modules.order, $m),     \
 423                         cat $m;, echo kernel/$m;))
 424
 425 $(modorder-target): $(subdir-ym) FORCE
 426         $(Q)(cat /dev/null; $(modorder-cmds)) > $@
 427
 428 #
 429 # Rule to compile a set of .o files into one .a file
 430 #
 431 ifdef lib-target
 432 quiet_cmd_link_l_target = AR      $@
 433 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
 434
 435 $(lib-target): $(lib-y) FORCE
 436         $(call if_changed,link_l_target)
 437
 438 targets += $(lib-target)
 439 endif
 440
 441 #
 442 # Rule to link composite objects
 443 #
 444 #  Composite objects are specified in kbuild makefile as follows:
 445 #    <composite-object>-objs := <list of .o files>
 446 #  or
 447 #    <composite-object>-y    := <list of .o files>
 448 link_multi_deps =                     \
 449 $(filter $(addprefix $(obj)/,         \
 450 $($(subst $(obj)/,,$(@:.o=-objs)))    \
 451 $($(subst $(obj)/,,$(@:.o=-y)))), $^)
 452
 453 quiet_cmd_link_multi-y = LD      $@
 454 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
 455
 456 quiet_cmd_link_multi-m = LD [M]  $@
 457 cmd_link_multi-m = $(cmd_link_multi-y)
 458
 459 $(multi-used-y): FORCE
 460         $(call if_changed,link_multi-y)
 461 $(call multi_depend, $(multi-used-y), .o, -objs -y)
 462
 463 $(multi-used-m): FORCE
 464         $(call if_changed,link_multi-m)
 465         @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod)
 466 $(call multi_depend, $(multi-used-m), .o, -objs -y)
 467
 468 targets += $(multi-used-y) $(multi-used-m)
 469
 470
 471 # Descending
 472 # ---------------------------------------------------------------------------
 473
 474 PHONY += $(subdir-ym)
 475 $(subdir-ym):
 476         $(Q)$(MAKE) $(build)=$@
 477
 478 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 479 # ---------------------------------------------------------------------------
 480
 481 PHONY += FORCE
 482
 483 FORCE:
 484
 485 # Read all saved command lines and dependencies for the $(targets) we
 486 # may be building above, using $(if_changed{,_dep}). As an
 487 # optimization, we don't need to read them if the target does not
 488 # exist, we will rebuild anyway in that case.
 489
 490 targets := $(wildcard $(sort $(targets)))
 491 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 492
 493 ifneq ($(cmd_files),)
 494   include $(cmd_files)
 495 endif
 496
 497 # Declare the contents of the .PHONY variable as phony.  We keep that
 498 # information in a variable se we can use it in if_changed and friends.
 499
 500 .PHONY: $(PHONY)