mirror of git://git.yoctoproject.org/linux-yocto.git synced 2025-07-09 23:35:22 +02:00

Lasse Collin 3ebe12439b decompressors: add boot-time XZ support

This implements the API defined in <linux/decompress/generic.h> which is
used for kernel, initramfs, and initrd decompression.  This patch together
with the first patch is enough for XZ-compressed initramfs and initrd;
XZ-compressed kernel will need arch-specific changes.

The buffering requirements described in decompress_unxz.c are stricter
than with gzip, so the relevant changes should be done to the
arch-specific code when adding support for XZ-compressed kernel.
Similarly, the heap size in arch-specific pre-boot code may need to be
increased (30 KiB is enough).

The XZ decompressor needs memmove(), memeq() (memcmp() == 0), and
memzero() (memset(ptr, 0, size)), which aren't available in all
arch-specific pre-boot environments.  I'm including simple versions in
decompress_unxz.c, but a cleaner solution would naturally be nicer.

Signed-off-by: Lasse Collin <lasse.collin@tukaani.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alain Knaff <alain@knaff.lu>
Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2011-01-13 08:03:25 -08:00

2.3 KiB

Raw Blame History

kbuild file for usr/ - including initramfs image

klibcdirs:; PHONY += klibcdirs

Gzip

suffix_$(CONFIG_INITRAMFS_COMPRESSION_GZIP) = .gz

Bzip2

suffix_$(CONFIG_INITRAMFS_COMPRESSION_BZIP2) = .bz2

Lzma

suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZMA) = .lzma

XZ

suffix_$(CONFIG_INITRAMFS_COMPRESSION_XZ) = .xz

Lzo

suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZO) = .lzo

AFLAGS_initramfs_data.o += -DINITRAMFS_IMAGE="usr/initramfs_data.cpio$(suffix_y)"

Generate builtin.o based on initramfs_data.o

obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o

initramfs_data.o contains the compressed initramfs_data.cpio image.

The image is included using .incbin, a dependency which is not

tracked automatically.

$(obj)/initramfs_data.o: $(obj)/initramfs_data.cpio$(suffix_y) FORCE

Generate the initramfs cpio archive

hostprogs-y := gen_init_cpio initramfs := $(CONFIG_SHELL) $(srctree)/scripts/gen_initramfs_list.sh ramfs-input := $(if $(filter-out "",$(CONFIG_INITRAMFS_SOURCE)),
$(shell echo $(CONFIG_INITRAMFS_SOURCE)),-d) ramfs-args :=
$(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID))
$(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID))

.initramfs_data.cpio.d is used to identify all files included

in initramfs and to detect if any files are added/removed.

Removed files are identified by directory timestamp being updated

The dependency list is generated by gen_initramfs.sh -l

ifneq ($(wildcard $(obj)/.initramfs_data.cpio.d),) include $(obj)/.initramfs_data.cpio.d endif

quiet_cmd_initfs = GEN $@ cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)

targets := initramfs_data.cpio.gz initramfs_data.cpio.bz2 initramfs_data.cpio.lzma initramfs_data.cpio.xz initramfs_data.cpio.lzo initramfs_data.cpio

do not try to update files included in initramfs

$(deps_initramfs): ;

$(deps_initramfs): klibcdirs

We rebuild initramfs_data.cpio if:

1) Any included file is newer then initramfs_data.cpio

2) There are changes in which files are included (added or deleted)

3) If gen_init_cpio are newer than initramfs_data.cpio

4) arguments to gen_initramfs.sh changes

$(obj)/initramfs_data.cpio$(suffix_y): $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs $(Q)$(initramfs) -l $(ramfs-input) > $(obj)/.initramfs_data.cpio.d $(call if_changed,initfs)

2.3 KiB Raw Blame History