Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1# SPDX-License-Identifier: GPL-2.0
2# Backward compatibility
3asflags-y += $(EXTRA_AFLAGS)
4ccflags-y += $(EXTRA_CFLAGS)
5cppflags-y += $(EXTRA_CPPFLAGS)
6ldflags-y += $(EXTRA_LDFLAGS)
7
8# flags that take effect in current and sub directories
9KBUILD_AFLAGS += $(subdir-asflags-y)
10KBUILD_CFLAGS += $(subdir-ccflags-y)
11KBUILD_RUSTFLAGS += $(subdir-rustflags-y)
12
13# Figure out what we need to build from the various variables
14# ===========================================================================
15
16# When an object is listed to be built compiled-in and modular,
17# only build the compiled-in version
18obj-m := $(filter-out $(obj-y),$(obj-m))
19
20# Libraries are always collected in one lib file.
21# Filter out objects already built-in
22lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
23
24# Subdirectories we need to descend into
25subdir-ym := $(sort $(subdir-y) $(subdir-m) \
26 $(patsubst %/,%, $(filter %/, $(obj-y) $(obj-m))))
27
28# Handle objects in subdirs:
29# - If we encounter foo/ in $(obj-y), replace it by foo/built-in.a and
30# foo/modules.order
31# - If we encounter foo/ in $(obj-m), replace it by foo/modules.order
32#
33# Generate modules.order to determine modorder. Unfortunately, we don't have
34# information about ordering between -y and -m subdirs. Just put -y's first.
35
36ifdef need-modorder
37obj-m := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m))
38else
39obj-m := $(filter-out %/, $(obj-m))
40endif
41
42ifdef need-builtin
43obj-y := $(patsubst %/, %/built-in.a, $(obj-y))
44else
45obj-y := $(filter-out %/, $(obj-y))
46endif
47
48# Expand $(foo-objs) $(foo-y) etc. by replacing their individuals
49suffix-search = $(strip $(foreach s, $3, $($(1:%$(strip $2)=%$s))))
50# List composite targets that are constructed by combining other targets
51multi-search = $(sort $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $m)))
52# List primitive targets that are compiled from source files
53real-search = $(foreach m, $1, $(if $(call suffix-search, $m, $2, $3 -), $(call suffix-search, $m, $2, $3), $m))
54
55# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
56multi-obj-y := $(call multi-search, $(obj-y), .o, -objs -y)
57multi-obj-m := $(call multi-search, $(obj-m), .o, -objs -y -m)
58multi-obj-ym := $(multi-obj-y) $(multi-obj-m)
59
60# Replace multi-part objects by their individual parts,
61# including built-in.a from subdirectories
62real-obj-y := $(call real-search, $(obj-y), .o, -objs -y)
63real-obj-m := $(call real-search, $(obj-m), .o, -objs -y -m)
64
65always-y += $(always-m)
66
67# hostprogs-always-y += foo
68# ... is a shorthand for
69# hostprogs += foo
70# always-y += foo
71hostprogs += $(hostprogs-always-y) $(hostprogs-always-m)
72always-y += $(hostprogs-always-y) $(hostprogs-always-m)
73
74# userprogs-always-y is likewise.
75userprogs += $(userprogs-always-y) $(userprogs-always-m)
76always-y += $(userprogs-always-y) $(userprogs-always-m)
77
78# Add subdir path
79
80ifneq ($(obj),.)
81extra-y := $(addprefix $(obj)/,$(extra-y))
82always-y := $(addprefix $(obj)/,$(always-y))
83targets := $(addprefix $(obj)/,$(targets))
84obj-m := $(addprefix $(obj)/,$(obj-m))
85lib-y := $(addprefix $(obj)/,$(lib-y))
86real-obj-y := $(addprefix $(obj)/,$(real-obj-y))
87real-obj-m := $(addprefix $(obj)/,$(real-obj-m))
88multi-obj-m := $(addprefix $(obj)/, $(multi-obj-m))
89subdir-ym := $(addprefix $(obj)/,$(subdir-ym))
90endif
91
92# Finds the multi-part object the current object will be linked into.
93# If the object belongs to two or more multi-part objects, list them all.
94modname-multi = $(sort $(foreach m,$(multi-obj-ym),\
95 $(if $(filter $*.o, $(call suffix-search, $m, .o, -objs -y -m)),$(m:.o=))))
96
97__modname = $(or $(modname-multi),$(basetarget))
98
99modname = $(subst $(space),:,$(__modname))
100modfile = $(addprefix $(obj)/,$(__modname))
101
102# target with $(obj)/ and its suffix stripped
103target-stem = $(basename $(patsubst $(obj)/%,%,$@))
104
105# These flags are needed for modversions and compiling, so we define them here
106# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
107# end up in (or would, if it gets compiled in)
108name-fix-token = $(subst $(comma),_,$(subst -,_,$1))
109name-fix = $(call stringify,$(call name-fix-token,$1))
110basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
111modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) \
112 -D__KBUILD_MODNAME=kmod_$(call name-fix-token,$(modname))
113modfile_flags = -DKBUILD_MODFILE=$(call stringify,$(modfile))
114
115_c_flags = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), \
116 $(filter-out $(ccflags-remove-y), \
117 $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(ccflags-y)) \
118 $(CFLAGS_$(target-stem).o))
119_rust_flags = $(filter-out $(RUSTFLAGS_REMOVE_$(target-stem).o), \
120 $(filter-out $(rustflags-remove-y), \
121 $(KBUILD_RUSTFLAGS) $(rustflags-y)) \
122 $(RUSTFLAGS_$(target-stem).o))
123_a_flags = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), \
124 $(filter-out $(asflags-remove-y), \
125 $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(asflags-y)) \
126 $(AFLAGS_$(target-stem).o))
127_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
128
129#
130# Enable gcov profiling flags for a file, directory or for all files depending
131# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
132# (in this order)
133#
134ifeq ($(CONFIG_GCOV_KERNEL),y)
135_c_flags += $(if $(patsubst n%,, \
136 $(GCOV_PROFILE_$(target-stem).o)$(GCOV_PROFILE)$(if $(is-kernel-object),$(CONFIG_GCOV_PROFILE_ALL))), \
137 $(CFLAGS_GCOV))
138endif
139
140#
141# Enable address sanitizer flags for kernel except some files or directories
142# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
143#
144ifeq ($(CONFIG_KASAN),y)
145ifneq ($(CONFIG_KASAN_HW_TAGS),y)
146_c_flags += $(if $(patsubst n%,, \
147 $(KASAN_SANITIZE_$(target-stem).o)$(KASAN_SANITIZE)$(is-kernel-object)), \
148 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
149_rust_flags += $(if $(patsubst n%,, \
150 $(KASAN_SANITIZE_$(target-stem).o)$(KASAN_SANITIZE)$(is-kernel-object)), \
151 $(RUSTFLAGS_KASAN))
152endif
153endif
154
155ifeq ($(CONFIG_KMSAN),y)
156_c_flags += $(if $(patsubst n%,, \
157 $(KMSAN_SANITIZE_$(target-stem).o)$(KMSAN_SANITIZE)$(is-kernel-object)), \
158 $(CFLAGS_KMSAN))
159_c_flags += $(if $(patsubst n%,, \
160 $(KMSAN_ENABLE_CHECKS_$(target-stem).o)$(KMSAN_ENABLE_CHECKS)$(is-kernel-object)), \
161 , -mllvm -msan-disable-checks=1)
162endif
163
164ifeq ($(CONFIG_UBSAN),y)
165_c_flags += $(if $(patsubst n%,, \
166 $(UBSAN_SANITIZE_$(target-stem).o)$(UBSAN_SANITIZE)$(is-kernel-object)), \
167 $(CFLAGS_UBSAN))
168_c_flags += $(if $(patsubst n%,, \
169 $(UBSAN_SIGNED_WRAP_$(target-stem).o)$(UBSAN_SANITIZE_$(target-stem).o)$(UBSAN_SIGNED_WRAP)$(UBSAN_SANITIZE)$(is-kernel-object)), \
170 $(CFLAGS_UBSAN_SIGNED_WRAP))
171endif
172
173ifeq ($(CONFIG_KCOV),y)
174_c_flags += $(if $(patsubst n%,, \
175 $(KCOV_INSTRUMENT_$(target-stem).o)$(KCOV_INSTRUMENT)$(if $(is-kernel-object),$(CONFIG_KCOV_INSTRUMENT_ALL))), \
176 $(CFLAGS_KCOV))
177endif
178
179#
180# Enable KCSAN flags except some files or directories we don't want to check
181# (depends on variables KCSAN_SANITIZE_obj.o, KCSAN_SANITIZE)
182#
183ifeq ($(CONFIG_KCSAN),y)
184_c_flags += $(if $(patsubst n%,, \
185 $(KCSAN_SANITIZE_$(target-stem).o)$(KCSAN_SANITIZE)$(is-kernel-object)), \
186 $(CFLAGS_KCSAN))
187# Some uninstrumented files provide implied barriers required to avoid false
188# positives: set KCSAN_INSTRUMENT_BARRIERS for barrier instrumentation only.
189_c_flags += $(if $(patsubst n%,, \
190 $(KCSAN_INSTRUMENT_BARRIERS_$(target-stem).o)$(KCSAN_INSTRUMENT_BARRIERS)n), \
191 -D__KCSAN_INSTRUMENT_BARRIERS__)
192endif
193
194#
195# Enable AutoFDO build flags except some files or directories we don't want to
196# enable (depends on variables AUTOFDO_PROFILE_obj.o and AUTOFDO_PROFILE).
197#
198ifeq ($(CONFIG_AUTOFDO_CLANG),y)
199_c_flags += $(if $(patsubst n%,, \
200 $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(is-kernel-object)), \
201 $(CFLAGS_AUTOFDO_CLANG))
202endif
203
204#
205# Enable Propeller build flags except some files or directories we don't want to
206# enable (depends on variables AUTOFDO_PROPELLER_obj.o and PROPELLER_PROFILE).
207#
208ifdef CONFIG_PROPELLER_CLANG
209_c_flags += $(if $(patsubst n%,, \
210 $(AUTOFDO_PROFILE_$(target-stem).o)$(AUTOFDO_PROFILE)$(PROPELLER_PROFILE))$(is-kernel-object), \
211 $(CFLAGS_PROPELLER_CLANG))
212endif
213
214# $(src) for including checkin headers from generated source files
215# $(obj) for including generated headers from checkin source files
216ifdef building_out_of_srctree
217_c_flags += $(addprefix -I, $(src) $(obj))
218_a_flags += $(addprefix -I, $(src) $(obj))
219_cpp_flags += $(addprefix -I, $(src) $(obj))
220endif
221
222# If $(is-kernel-object) is 'y', this object will be linked to vmlinux or modules
223is-kernel-object = $(or $(part-of-builtin),$(part-of-module))
224
225part-of-builtin = $(if $(filter $(basename $@).o, $(real-obj-y) $(lib-y)),y)
226part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y)
227quiet_modtag = $(if $(part-of-module),[M], )
228
229modkern_cflags = \
230 $(if $(part-of-module), \
231 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
232 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL) $(modfile_flags))
233
234modkern_rustflags = \
235 $(if $(part-of-module), \
236 $(KBUILD_RUSTFLAGS_MODULE) $(RUSTFLAGS_MODULE), \
237 $(KBUILD_RUSTFLAGS_KERNEL) $(RUSTFLAGS_KERNEL))
238
239modkern_aflags = $(if $(part-of-module), \
240 $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE), \
241 $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL) $(modfile_flags))
242
243c_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
244 -include $(srctree)/include/linux/compiler_types.h \
245 $(_c_flags) $(modkern_cflags) \
246 $(basename_flags) $(modname_flags)
247
248rust_flags = $(_rust_flags) $(modkern_rustflags) @$(objtree)/include/generated/rustc_cfg
249
250a_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
251 $(_a_flags) $(modkern_aflags) $(modname_flags)
252
253cpp_flags = -Wp,-MMD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \
254 $(_cpp_flags)
255
256ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
257
258ifdef CONFIG_OBJTOOL
259
260objtool := $(objtree)/tools/objtool/objtool
261
262objtool-args-$(CONFIG_HAVE_JUMP_LABEL_HACK) += --hacks=jump_label
263objtool-args-$(CONFIG_HAVE_NOINSTR_HACK) += --hacks=noinstr
264objtool-args-$(CONFIG_MITIGATION_CALL_DEPTH_TRACKING) += --hacks=skylake
265objtool-args-$(CONFIG_X86_KERNEL_IBT) += --ibt
266objtool-args-$(CONFIG_FINEIBT) += --cfi
267objtool-args-$(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL) += --mcount
268ifdef CONFIG_FTRACE_MCOUNT_USE_OBJTOOL
269objtool-args-$(CONFIG_HAVE_OBJTOOL_NOP_MCOUNT) += --mnop
270endif
271objtool-args-$(CONFIG_UNWINDER_ORC) += --orc
272objtool-args-$(CONFIG_MITIGATION_RETPOLINE) += --retpoline
273objtool-args-$(CONFIG_MITIGATION_RETHUNK) += --rethunk
274objtool-args-$(CONFIG_MITIGATION_SLS) += --sls
275objtool-args-$(CONFIG_STACK_VALIDATION) += --stackval
276objtool-args-$(CONFIG_HAVE_STATIC_CALL_INLINE) += --static-call
277objtool-args-$(CONFIG_HAVE_UACCESS_VALIDATION) += --uaccess
278objtool-args-$(CONFIG_GCOV_KERNEL) += --no-unreachable
279objtool-args-$(CONFIG_PREFIX_SYMBOLS) += --prefix=$(CONFIG_FUNCTION_PADDING_BYTES)
280
281objtool-args = $(objtool-args-y) \
282 $(if $(delay-objtool), --link) \
283 $(if $(part-of-module), --module)
284
285delay-objtool := $(or $(CONFIG_LTO_CLANG),$(CONFIG_X86_KERNEL_IBT))
286
287cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool-args) $@)
288cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
289
290objtool-enabled := y
291
292endif # CONFIG_OBJTOOL
293
294# Useful for describing the dependency of composite objects
295# Usage:
296# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
297define multi_depend
298$(foreach m, $1, \
299 $(eval $m: \
300 $(addprefix $(obj)/, $(call suffix-search, $(patsubst $(obj)/%,%,$m), $2, $3))))
301endef
302
303# Build commands
304# ===========================================================================
305# These are shared by some Makefile.* files.
306
307ifdef CONFIG_LTO_CLANG
308# Run $(LD) here to convert LLVM IR to ELF in the following cases:
309# - when this object needs objtool processing, as objtool cannot process LLVM IR
310# - when this is a single-object module, as modpost cannot process LLVM IR
311cmd_ld_single = $(if $(objtool-enabled)$(is-single-obj-m), ; $(LD) $(ld_flags) -r -o $(tmp-target) $@; mv $(tmp-target) $@)
312endif
313
314quiet_cmd_cc_o_c = CC $(quiet_modtag) $@
315 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< \
316 $(cmd_ld_single) \
317 $(cmd_objtool)
318
319define rule_cc_o_c
320 $(call cmd_and_fixdep,cc_o_c)
321 $(call cmd,checksrc)
322 $(call cmd,checkdoc)
323 $(call cmd,gen_objtooldep)
324 $(call cmd,gen_symversions_c)
325 $(call cmd,record_mcount)
326 $(call cmd,warn_shared_object)
327endef
328
329quiet_cmd_as_o_S = AS $(quiet_modtag) $@
330 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< $(cmd_objtool)
331
332define rule_as_o_S
333 $(call cmd_and_fixdep,as_o_S)
334 $(call cmd,gen_objtooldep)
335 $(call cmd,gen_symversions_S)
336 $(call cmd,warn_shared_object)
337endef
338
339# Copy a file
340# ===========================================================================
341# 'cp' preserves permissions. If you use it to copy a file in read-only srctree,
342# the copy would be read-only as well, leading to an error when executing the
343# rule next time. Use 'cat' instead in order to generate a writable file.
344quiet_cmd_copy = COPY $@
345 cmd_copy = cat $< > $@
346
347$(obj)/%: $(src)/%_shipped
348 $(call cmd,copy)
349
350# Commands useful for building a boot image
351# ===========================================================================
352#
353# Use as following:
354#
355# target: source(s) FORCE
356# $(if_changed,ld/objcopy/gzip)
357#
358# and add target to 'targets' so that we know we have to
359# read in the saved command line
360
361# Linking
362# ---------------------------------------------------------------------------
363
364quiet_cmd_ld = LD $@
365 cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
366
367# Archive
368# ---------------------------------------------------------------------------
369
370quiet_cmd_ar = AR $@
371 cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
372
373# Objcopy
374# ---------------------------------------------------------------------------
375
376quiet_cmd_objcopy = OBJCOPY $@
377cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
378
379quiet_cmd_strip_relocs = RSTRIP $@
380cmd_strip_relocs = $(OBJCOPY) --remove-section='.rel*' $@
381
382# Gzip
383# ---------------------------------------------------------------------------
384
385quiet_cmd_gzip = GZIP $@
386 cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@
387
388# Bzip2
389# ---------------------------------------------------------------------------
390
391# Bzip2 and LZMA do not include size in file... so we have to fake that;
392# append the size as a 32-bit littleendian number as gzip does.
393size_append = printf $(shell \
394dec_size=0; \
395for F in $(real-prereqs); do \
396 fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F); \
397 dec_size=$$(expr $$dec_size + $$fsize); \
398done; \
399printf "%08x\n" $$dec_size | \
400 sed 's/\(..\)/\1 /g' | { \
401 read ch0 ch1 ch2 ch3; \
402 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \
403 printf '%s%03o' '\\' $$((0x$$ch)); \
404 done; \
405 } \
406)
407
408quiet_cmd_file_size = GEN $@
409 cmd_file_size = $(size_append) > $@
410
411quiet_cmd_bzip2 = BZIP2 $@
412 cmd_bzip2 = cat $(real-prereqs) | $(KBZIP2) -9 > $@
413
414quiet_cmd_bzip2_with_size = BZIP2 $@
415 cmd_bzip2_with_size = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
416
417# Lzma
418# ---------------------------------------------------------------------------
419
420quiet_cmd_lzma = LZMA $@
421 cmd_lzma = cat $(real-prereqs) | $(LZMA) -9 > $@
422
423quiet_cmd_lzma_with_size = LZMA $@
424 cmd_lzma_with_size = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@
425
426quiet_cmd_lzo = LZO $@
427 cmd_lzo = cat $(real-prereqs) | $(KLZOP) -9 > $@
428
429quiet_cmd_lzo_with_size = LZO $@
430 cmd_lzo_with_size = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@
431
432quiet_cmd_lz4 = LZ4 $@
433 cmd_lz4 = cat $(real-prereqs) | $(LZ4) -l -9 - - > $@
434
435quiet_cmd_lz4_with_size = LZ4 $@
436 cmd_lz4_with_size = { cat $(real-prereqs) | $(LZ4) -l -9 - -; \
437 $(size_append); } > $@
438
439# U-Boot mkimage
440# ---------------------------------------------------------------------------
441
442MKIMAGE := $(srctree)/scripts/mkuboot.sh
443
444# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
445# the number of overrides in arch makefiles
446UIMAGE_ARCH ?= $(SRCARCH)
447UIMAGE_COMPRESSION ?= $(or $(2),none)
448UIMAGE_OPTS-y ?=
449UIMAGE_TYPE ?= kernel
450UIMAGE_LOADADDR ?= arch_must_set_this
451UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
452UIMAGE_NAME ?= Linux-$(KERNELRELEASE)
453
454quiet_cmd_uimage = UIMAGE $@
455 cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
456 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
457 -T $(UIMAGE_TYPE) \
458 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
459 -n '$(UIMAGE_NAME)' -d $< $@
460
461# Flat Image Tree (FIT)
462# This allows for packaging of a kernel and all devicetrees files, using
463# compression.
464# ---------------------------------------------------------------------------
465
466MAKE_FIT := $(srctree)/scripts/make_fit.py
467
468# Use this to override the compression algorithm
469FIT_COMPRESSION ?= gzip
470
471quiet_cmd_fit = FIT $@
472 cmd_fit = $(MAKE_FIT) -o $@ --arch $(UIMAGE_ARCH) --os linux \
473 --name '$(UIMAGE_NAME)' \
474 $(if $(findstring 1,$(KBUILD_VERBOSE)),-v) \
475 $(if $(FIT_DECOMPOSE_DTBS),--decompose-dtbs) \
476 --compress $(FIT_COMPRESSION) -k $< @$(word 2,$^)
477
478# XZ
479# ---------------------------------------------------------------------------
480# Use xzkern or xzkern_with_size to compress the kernel image and xzmisc to
481# compress other things.
482#
483# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
484# of the kernel decompressor. A BCJ filter is used if it is available for
485# the target architecture.
486#
487# xzkern_with_size also appends uncompressed size of the data using
488# size_append. The .xz format has the size information available at the end
489# of the file too, but it's in more complex format and it's good to avoid
490# changing the part of the boot code that reads the uncompressed size.
491# Note that the bytes added by size_append will make the xz tool think that
492# the file is corrupt. This is expected.
493#
494# xzmisc doesn't use size_append, so it can be used to create normal .xz
495# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
496# big dictionary would increase the memory usage too much in the multi-call
497# decompression mode. A BCJ filter isn't used either.
498quiet_cmd_xzkern = XZKERN $@
499 cmd_xzkern = cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh > $@
500
501quiet_cmd_xzkern_with_size = XZKERN $@
502 cmd_xzkern_with_size = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
503 $(size_append); } > $@
504
505quiet_cmd_xzmisc = XZMISC $@
506 cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@
507
508# ZSTD
509# ---------------------------------------------------------------------------
510# Appends the uncompressed size of the data using size_append. The .zst
511# format has the size information available at the beginning of the file too,
512# but it's in a more complex format and it's good to avoid changing the part
513# of the boot code that reads the uncompressed size.
514#
515# Note that the bytes added by size_append will make the zstd tool think that
516# the file is corrupt. This is expected.
517#
518# zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of
519# 128 MB. zstd22 is used for kernel compression because it is decompressed in a
520# single pass, so zstd doesn't need to allocate a window buffer. When streaming
521# decompression is used, like initramfs decompression, zstd22 should likely not
522# be used because it would require zstd to allocate a 128 MB buffer.
523
524quiet_cmd_zstd = ZSTD $@
525 cmd_zstd = cat $(real-prereqs) | $(ZSTD) -19 > $@
526
527quiet_cmd_zstd22 = ZSTD22 $@
528 cmd_zstd22 = cat $(real-prereqs) | $(ZSTD) -22 --ultra > $@
529
530quiet_cmd_zstd22_with_size = ZSTD22 $@
531 cmd_zstd22_with_size = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@
532
533# ASM offsets
534# ---------------------------------------------------------------------------
535
536# Default sed regexp - multiline due to syntax constraints
537#
538# Use [:space:] because LLVM's integrated assembler inserts <tab> around
539# the .ascii directive whereas GCC keeps the <space> as-is.
540define sed-offsets
541 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
542 /^->/{s:->#\(.*\):/* \1 */:; \
543 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
544 s:->::; p;}'
545endef
546
547# Use filechk to avoid rebuilds when a header changes, but the resulting file
548# does not
549define filechk_offsets
550 echo "#ifndef $2"; \
551 echo "#define $2"; \
552 echo "/*"; \
553 echo " * DO NOT MODIFY."; \
554 echo " *"; \
555 echo " * This file was generated by Kbuild"; \
556 echo " */"; \
557 echo ""; \
558 sed -ne $(sed-offsets) < $<; \
559 echo ""; \
560 echo "#endif"
561endef