projects/linux·blob v5.8 · refs

88 lines · 2.9 KiB

1# SPDX-License-Identifier: GPL-2.0
2#
3# kbuild file for usr/ - including initramfs image
4#
5
6# cmd_bzip2, cmd_lzma, cmd_lzo, cmd_lz4 from scripts/Makefile.lib appends the
7# size at the end of the compressed file, which unfortunately does not work
8# with unpack_to_rootfs(). Make size_append no-op.
9override size_append := :
10
11compress-y := shipped
12compress-$(CONFIG_INITRAMFS_COMPRESSION_GZIP) := gzip
13compress-$(CONFIG_INITRAMFS_COMPRESSION_BZIP2) := bzip2
14compress-$(CONFIG_INITRAMFS_COMPRESSION_LZMA) := lzma
15compress-$(CONFIG_INITRAMFS_COMPRESSION_XZ) := xzmisc
16compress-$(CONFIG_INITRAMFS_COMPRESSION_LZO) := lzo
17compress-$(CONFIG_INITRAMFS_COMPRESSION_LZ4) := lz4
18
19obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
20
21$(obj)/initramfs_data.o: $(obj)/initramfs_inc_data
22
23ramfs-input := $(strip $(shell echo $(CONFIG_INITRAMFS_SOURCE)))
24cpio-data :=
25
26# If CONFIG_INITRAMFS_SOURCE is empty, generate a small initramfs with the
27# default contents.
28ifeq ($(ramfs-input),)
29ramfs-input := $(srctree)/$(src)/default_cpio_list
30endif
31
32ifeq ($(words $(ramfs-input)),1)
33
34# If CONFIG_INITRAMFS_SOURCE specifies a single file, and it is suffixed with
35# .cpio, use it directly as an initramfs.
36ifneq ($(filter %.cpio,$(ramfs-input)),)
37cpio-data := $(ramfs-input)
38endif
39
40# If CONFIG_INITRAMFS_SOURCE specifies a single file, and it is suffixed with
41# .cpio.*, use it directly as an initramfs, and avoid double compression.
42ifeq ($(words $(subst .cpio.,$(space),$(ramfs-input))),2)
43cpio-data := $(ramfs-input)
44compress-y := shipped
45endif
46
47endif
48
49# For other cases, generate the initramfs cpio archive based on the contents
50# specified by CONFIG_INITRAMFS_SOURCE.
51ifeq ($(cpio-data),)
52
53cpio-data := $(obj)/initramfs_data.cpio
54
55hostprogs := gen_init_cpio
56
57# .initramfs_data.cpio.d is used to identify all files included
58# in initramfs and to detect if any files are added/removed.
59# Removed files are identified by directory timestamp being updated
60# The dependency list is generated by gen_initramfs.sh -l
61-include $(obj)/.initramfs_data.cpio.d
62
63# do not try to update files included in initramfs
64$(deps_initramfs): ;
65
66quiet_cmd_initfs = GEN $@
67 cmd_initfs = \
68 $(CONFIG_SHELL) $< -o $@ -l $(obj)/.initramfs_data.cpio.d \
69 $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
70 $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID)) \
71 $(ramfs-input)
72
73# We rebuild initramfs_data.cpio if:
74# 1) Any included file is newer than initramfs_data.cpio
75# 2) There are changes in which files are included (added or deleted)
76# 3) If gen_init_cpio are newer than initramfs_data.cpio
77# 4) Arguments to gen_initramfs.sh changes
78$(obj)/initramfs_data.cpio: $(src)/gen_initramfs.sh $(obj)/gen_init_cpio $(deps_initramfs) FORCE
79 $(call if_changed,initfs)
80
81endif
82
83$(obj)/initramfs_inc_data: $(cpio-data) FORCE
84 $(call if_changed,$(compress-y))
85
86targets += initramfs_data.cpio initramfs_inc_data
87
88subdir-$(CONFIG_UAPI_HEADER_TEST) += include