xref: /linux/scripts/Makefile.lib (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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
290endif # CONFIG_OBJTOOL
291
292# Useful for describing the dependency of composite objects
293# Usage:
294#   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
295define multi_depend
296$(foreach m, $1, \
297	$(eval $m: \
298	$(addprefix $(obj)/, $(call suffix-search, $(patsubst $(obj)/%,%,$m), $2, $3))))
299endef
300
301# Build commands
302# ===========================================================================
303# These are shared by some Makefile.* files.
304
305objtool-enabled := y
306
307ifdef CONFIG_LTO_CLANG
308# objtool cannot process LLVM IR. Make $(LD) covert LLVM IR to ELF here.
309cmd_ld_single = $(if $(objtool-enabled), ; $(LD) $(ld_flags) -r -o $(tmp-target) $@; mv $(tmp-target) $@)
310endif
311
312quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
313      cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< \
314		$(cmd_ld_single) \
315		$(cmd_objtool)
316
317define rule_cc_o_c
318	$(call cmd_and_fixdep,cc_o_c)
319	$(call cmd,checksrc)
320	$(call cmd,checkdoc)
321	$(call cmd,gen_objtooldep)
322	$(call cmd,gen_symversions_c)
323	$(call cmd,record_mcount)
324	$(call cmd,warn_shared_object)
325endef
326
327quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
328      cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $< $(cmd_objtool)
329
330define rule_as_o_S
331	$(call cmd_and_fixdep,as_o_S)
332	$(call cmd,gen_objtooldep)
333	$(call cmd,gen_symversions_S)
334	$(call cmd,warn_shared_object)
335endef
336
337# Copy a file
338# ===========================================================================
339# 'cp' preserves permissions. If you use it to copy a file in read-only srctree,
340# the copy would be read-only as well, leading to an error when executing the
341# rule next time. Use 'cat' instead in order to generate a writable file.
342quiet_cmd_copy = COPY    $@
343      cmd_copy = cat $< > $@
344
345$(obj)/%: $(src)/%_shipped
346	$(call cmd,copy)
347
348# Commands useful for building a boot image
349# ===========================================================================
350#
351#	Use as following:
352#
353#	target: source(s) FORCE
354#		$(if_changed,ld/objcopy/gzip)
355#
356#	and add target to 'targets' so that we know we have to
357#	read in the saved command line
358
359# Linking
360# ---------------------------------------------------------------------------
361
362quiet_cmd_ld = LD      $@
363      cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
364
365# Archive
366# ---------------------------------------------------------------------------
367
368quiet_cmd_ar = AR      $@
369      cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
370
371# Objcopy
372# ---------------------------------------------------------------------------
373
374quiet_cmd_objcopy = OBJCOPY $@
375cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
376
377# Gzip
378# ---------------------------------------------------------------------------
379
380quiet_cmd_gzip = GZIP    $@
381      cmd_gzip = cat $(real-prereqs) | $(KGZIP) -n -f -9 > $@
382
383# Bzip2
384# ---------------------------------------------------------------------------
385
386# Bzip2 and LZMA do not include size in file... so we have to fake that;
387# append the size as a 32-bit littleendian number as gzip does.
388size_append = printf $(shell						\
389dec_size=0;								\
390for F in $(real-prereqs); do					\
391	fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F);	\
392	dec_size=$$(expr $$dec_size + $$fsize);				\
393done;									\
394printf "%08x\n" $$dec_size |						\
395	sed 's/\(..\)/\1 /g' | {					\
396		read ch0 ch1 ch2 ch3;					\
397		for ch in $$ch3 $$ch2 $$ch1 $$ch0; do			\
398			printf '%s%03o' '\\' $$((0x$$ch)); 		\
399		done;							\
400	}								\
401)
402
403quiet_cmd_file_size = GEN     $@
404      cmd_file_size = $(size_append) > $@
405
406quiet_cmd_bzip2 = BZIP2   $@
407      cmd_bzip2 = cat $(real-prereqs) | $(KBZIP2) -9 > $@
408
409quiet_cmd_bzip2_with_size = BZIP2   $@
410      cmd_bzip2_with_size = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
411
412# Lzma
413# ---------------------------------------------------------------------------
414
415quiet_cmd_lzma = LZMA    $@
416      cmd_lzma = cat $(real-prereqs) | $(LZMA) -9 > $@
417
418quiet_cmd_lzma_with_size = LZMA    $@
419      cmd_lzma_with_size = { cat $(real-prereqs) | $(LZMA) -9; $(size_append); } > $@
420
421quiet_cmd_lzo = LZO     $@
422      cmd_lzo = cat $(real-prereqs) | $(KLZOP) -9 > $@
423
424quiet_cmd_lzo_with_size = LZO     $@
425      cmd_lzo_with_size = { cat $(real-prereqs) | $(KLZOP) -9; $(size_append); } > $@
426
427quiet_cmd_lz4 = LZ4     $@
428      cmd_lz4 = cat $(real-prereqs) | $(LZ4) -l -9 - - > $@
429
430quiet_cmd_lz4_with_size = LZ4     $@
431      cmd_lz4_with_size = { cat $(real-prereqs) | $(LZ4) -l -9 - -; \
432                  $(size_append); } > $@
433
434# U-Boot mkimage
435# ---------------------------------------------------------------------------
436
437MKIMAGE := $(srctree)/scripts/mkuboot.sh
438
439# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
440# the number of overrides in arch makefiles
441UIMAGE_ARCH ?= $(SRCARCH)
442UIMAGE_COMPRESSION ?= $(or $(2),none)
443UIMAGE_OPTS-y ?=
444UIMAGE_TYPE ?= kernel
445UIMAGE_LOADADDR ?= arch_must_set_this
446UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
447UIMAGE_NAME ?= Linux-$(KERNELRELEASE)
448
449quiet_cmd_uimage = UIMAGE  $@
450      cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
451			-C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
452			-T $(UIMAGE_TYPE) \
453			-a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
454			-n '$(UIMAGE_NAME)' -d $< $@
455
456# Flat Image Tree (FIT)
457# This allows for packaging of a kernel and all devicetrees files, using
458# compression.
459# ---------------------------------------------------------------------------
460
461MAKE_FIT := $(srctree)/scripts/make_fit.py
462
463# Use this to override the compression algorithm
464FIT_COMPRESSION ?= gzip
465
466quiet_cmd_fit = FIT     $@
467      cmd_fit = $(MAKE_FIT) -o $@ --arch $(UIMAGE_ARCH) --os linux \
468		--name '$(UIMAGE_NAME)' \
469		$(if $(findstring 1,$(KBUILD_VERBOSE)),-v) \
470		$(if $(FIT_DECOMPOSE_DTBS),--decompose-dtbs) \
471		--compress $(FIT_COMPRESSION) -k $< @$(word 2,$^)
472
473# XZ
474# ---------------------------------------------------------------------------
475# Use xzkern or xzkern_with_size to compress the kernel image and xzmisc to
476# compress other things.
477#
478# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
479# of the kernel decompressor. A BCJ filter is used if it is available for
480# the target architecture.
481#
482# xzkern_with_size also appends uncompressed size of the data using
483# size_append. The .xz format has the size information available at the end
484# of the file too, but it's in more complex format and it's good to avoid
485# changing the part of the boot code that reads the uncompressed size.
486# Note that the bytes added by size_append will make the xz tool think that
487# the file is corrupt. This is expected.
488#
489# xzmisc doesn't use size_append, so it can be used to create normal .xz
490# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
491# big dictionary would increase the memory usage too much in the multi-call
492# decompression mode. A BCJ filter isn't used either.
493quiet_cmd_xzkern = XZKERN  $@
494      cmd_xzkern = cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh > $@
495
496quiet_cmd_xzkern_with_size = XZKERN  $@
497      cmd_xzkern_with_size = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
498                     $(size_append); } > $@
499
500quiet_cmd_xzmisc = XZMISC  $@
501      cmd_xzmisc = cat $(real-prereqs) | $(XZ) --check=crc32 --lzma2=dict=1MiB > $@
502
503# ZSTD
504# ---------------------------------------------------------------------------
505# Appends the uncompressed size of the data using size_append. The .zst
506# format has the size information available at the beginning of the file too,
507# but it's in a more complex format and it's good to avoid changing the part
508# of the boot code that reads the uncompressed size.
509#
510# Note that the bytes added by size_append will make the zstd tool think that
511# the file is corrupt. This is expected.
512#
513# zstd uses a maximum window size of 8 MB. zstd22 uses a maximum window size of
514# 128 MB. zstd22 is used for kernel compression because it is decompressed in a
515# single pass, so zstd doesn't need to allocate a window buffer. When streaming
516# decompression is used, like initramfs decompression, zstd22 should likely not
517# be used because it would require zstd to allocate a 128 MB buffer.
518
519quiet_cmd_zstd = ZSTD    $@
520      cmd_zstd = cat $(real-prereqs) | $(ZSTD) -19 > $@
521
522quiet_cmd_zstd22 = ZSTD22  $@
523      cmd_zstd22 = cat $(real-prereqs) | $(ZSTD) -22 --ultra > $@
524
525quiet_cmd_zstd22_with_size = ZSTD22  $@
526      cmd_zstd22_with_size = { cat $(real-prereqs) | $(ZSTD) -22 --ultra; $(size_append); } > $@
527
528# ASM offsets
529# ---------------------------------------------------------------------------
530
531# Default sed regexp - multiline due to syntax constraints
532#
533# Use [:space:] because LLVM's integrated assembler inserts <tab> around
534# the .ascii directive whereas GCC keeps the <space> as-is.
535define sed-offsets
536	's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
537	/^->/{s:->#\(.*\):/* \1 */:; \
538	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
539	s:->::; p;}'
540endef
541
542# Use filechk to avoid rebuilds when a header changes, but the resulting file
543# does not
544define filechk_offsets
545	 echo "#ifndef $2"; \
546	 echo "#define $2"; \
547	 echo "/*"; \
548	 echo " * DO NOT MODIFY."; \
549	 echo " *"; \
550	 echo " * This file was generated by Kbuild"; \
551	 echo " */"; \
552	 echo ""; \
553	 sed -ne $(sed-offsets) < $<; \
554	 echo ""; \
555	 echo "#endif"
556endef
557