Commit Graph

3 Commits

Author SHA1 Message Date
Joel Stanley
242cdad873 lib/xz: Put CRC32_POLY_LE in xz_private.h
This fixes a regression introduced by faa16bc404 ("lib: Use
existing define with polynomial").

The cleanup added a dependency on include/linux, which broke the PowerPC
boot wrapper/decompresser when KERNEL_XZ is enabled:

  BOOTCC  arch/powerpc/boot/decompress.o
 In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:233,
                 from arch/powerpc/boot/decompress.c:42:
 arch/powerpc/boot/../../../lib/xz/xz_crc32.c:18:10: fatal error:
 linux/crc32poly.h: No such file or directory
  #include <linux/crc32poly.h>
           ^~~~~~~~~~~~~~~~~~~

The powerpc decompresser is a hairy corner of the kernel. Even while building
a 64-bit kernel it needs to build a 32-bit binary and therefore avoid including
files from include/linux.

This allows users of the xz library to avoid including headers from
'include/linux/' while still achieving the cleanup of the magic number.

Fixes: faa16bc404 ("lib: Use existing define with polynomial")
Reported-by: Meelis Roos <mroos@linux.ee>
Reported-by: kbuild test robot <lkp@intel.com>
Suggested-by: Christophe LEROY <christophe.leroy@c-s.fr>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-02 08:44:59 +10:00
Krzysztof Kozlowski
faa16bc404 lib: Use existing define with polynomial
Do not define again the polynomial but use header with existing define.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-27 19:16:38 +08:00
Lasse Collin
24fa0402a9 decompressors: add XZ decompressor module
In userspace, the .lzma format has become mostly a legacy file format that
got superseded by the .xz format.  Similarly, LZMA Utils was superseded by
XZ Utils.

These patches add support for XZ decompression into the kernel.  Most of
the code is as is from XZ Embedded <http://tukaani.org/xz/embedded.html>.
It was written for the Linux kernel but is usable in other projects too.

Advantages of XZ over the current LZMA code in the kernel:
  - Nice API that can be used by other kernel modules; it's
    not limited to kernel, initramfs, and initrd decompression.
  - Integrity check support (CRC32)
  - BCJ filters improve compression of executable code on
    certain architectures. These together with LZMA2 can
    produce a few percent smaller kernel or Squashfs images
    than plain LZMA without making the decompression slower.

This patch: Add the main decompression code (xz_dec), testing module
(xz_dec_test), wrapper script (xz_wrap.sh) for the xz command line tool,
and documentation.  The xz_dec module is enough to have a usable XZ
decompressor e.g.  for Squashfs.

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 08:03:24 -08:00