On Wed, 24 Nov 2010 22:51:52 +0200 Lasse Collin <lasse.collin@xxxxxxxxxxx> wrote: > From: Lasse Collin <lasse.collin@xxxxxxxxxxx> > > 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 file format that got superseded by the .xz format.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 LZMA Utils was superseded by XZ Utils.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. I'm not seeing any documentation which tells me how to create, install and execute xs-compressed kernels. There are new makefile targets? > > ... > > +#define bcj_x86_test_msbyte(b) ((b) == 0x00 || (b) == 0xFF) This should be written in C. It looks nicer, and so bcj_x86_test_msbyte(*p++) won't explode. > +static noinline_for_stack size_t bcj_x86( hm, but it uses little stack space. > +static noinline_for_stack size_t bcj_x86( > + struct xz_dec_bcj *s, uint8_t *buf, size_t size) The preferred style is static noinline_for_stack size_t bcj_x86(struct xz_dec_bcj *s, uint8_t *buf, size_t size) or static noinline_for_stack size_t bcj_x86(struct xz_dec_bcj *s, uint8_t *buf, size_t size) (lots of dittoes) -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
