• Lasse Collin's avatar
    decompressors: add boot-time XZ support · 3ebe1243
    Lasse Collin authored
    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: default avatarLasse 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: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Makefile 2.32 KB