alistair23-linux/include/linux/decompress/generic.h
Yinghai Lu d97b07c54f initramfs: support initramfs that is bigger than 2GiB
Now with 64bit bzImage and kexec tools, we support ramdisk that size is
bigger than 2g, as we could put it above 4G.

Found compressed initramfs image could not be decompressed properly.  It
turns out that image length is int during decompress detection, and it
will become < 0 when length is more than 2G.  Furthermore, during
decompressing len as int is used for inbuf count, that has problem too.

Change len to long, that should be ok as on 32 bit platform long is
32bits.

Tested with following compressed initramfs image as root with kexec.
	gzip, bzip2, xz, lzma, lzop, lz4.
run time for populate_rootfs():
   size        name       Nehalem-EX  Westmere-EX  Ivybridge-EX
 9034400256 root_img     :   26s           24s          30s
 3561095057 root_img.lz4 :   28s           27s          27s
 3459554629 root_img.lzo :   29s           29s          28s
 3219399480 root_img.gz  :   64s           62s          49s
 2251594592 root_img.xz  :  262s          260s         183s
 2226366598 root_img.lzma:  386s          376s         277s
 2901482513 root_img.bz2 :  635s          599s

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Rashika Kheria <rashika.kheria@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: P J P <ppandit@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: "Daniel M. Weeks" <dan@danweeks.net>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-08 15:57:26 -07:00

40 lines
1.4 KiB
C

#ifndef DECOMPRESS_GENERIC_H
#define DECOMPRESS_GENERIC_H
typedef int (*decompress_fn) (unsigned char *inbuf, long len,
long (*fill)(void*, unsigned long),
long (*flush)(void*, unsigned long),
unsigned char *outbuf,
long *posp,
void(*error)(char *x));
/* inbuf - input buffer
*len - len of pre-read data in inbuf
*fill - function to fill inbuf when empty
*flush - function to write out outbuf
*outbuf - output buffer
*posp - if non-null, input position (number of bytes read) will be
* returned here
*
*If len != 0, inbuf should contain all the necessary input data, and fill
*should be NULL
*If len = 0, inbuf can be NULL, in which case the decompressor will allocate
*the input buffer. If inbuf != NULL it must be at least XXX_IOBUF_SIZE bytes.
*fill will be called (repeatedly...) to read data, at most XXX_IOBUF_SIZE
*bytes should be read per call. Replace XXX with the appropriate decompressor
*name, i.e. LZMA_IOBUF_SIZE.
*
*If flush = NULL, outbuf must be large enough to buffer all the expected
*output. If flush != NULL, the output buffer will be allocated by the
*decompressor (outbuf = NULL), and the flush function will be called to
*flush the output buffer at the appropriate time (decompressor and stream
*dependent).
*/
/* Utility routine to detect the decompression method */
decompress_fn decompress_method(const unsigned char *inbuf, long len,
const char **name);
#endif