linux-hardened/fs/jffs2/compr_zlib.c
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

222 lines
5.5 KiB
C

/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright © 2001-2007 Red Hat, Inc.
* Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
*
* Created by David Woodhouse <dwmw2@infradead.org>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
*/
#if !defined(__KERNEL__) && !defined(__ECOS)
#error "The userspace support got too messy and was removed. Update your mkfs.jffs2"
#endif
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/zlib.h>
#include <linux/zutil.h>
#include "nodelist.h"
#include "compr.h"
/* Plan: call deflate() with avail_in == *sourcelen,
avail_out = *dstlen - 12 and flush == Z_FINISH.
If it doesn't manage to finish, call it again with
avail_in == 0 and avail_out set to the remaining 12
bytes for it to clean up.
Q: Is 12 bytes sufficient?
*/
#define STREAM_END_SPACE 12
static DEFINE_MUTEX(deflate_mutex);
static DEFINE_MUTEX(inflate_mutex);
static z_stream inf_strm, def_strm;
#ifdef __KERNEL__ /* Linux-only */
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/mutex.h>
static int __init alloc_workspaces(void)
{
def_strm.workspace = vmalloc(zlib_deflate_workspacesize(MAX_WBITS,
MAX_MEM_LEVEL));
if (!def_strm.workspace)
return -ENOMEM;
jffs2_dbg(1, "Allocated %d bytes for deflate workspace\n",
zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL));
inf_strm.workspace = vmalloc(zlib_inflate_workspacesize());
if (!inf_strm.workspace) {
vfree(def_strm.workspace);
return -ENOMEM;
}
jffs2_dbg(1, "Allocated %d bytes for inflate workspace\n",
zlib_inflate_workspacesize());
return 0;
}
static void free_workspaces(void)
{
vfree(def_strm.workspace);
vfree(inf_strm.workspace);
}
#else
#define alloc_workspaces() (0)
#define free_workspaces() do { } while(0)
#endif /* __KERNEL__ */
static int jffs2_zlib_compress(unsigned char *data_in,
unsigned char *cpage_out,
uint32_t *sourcelen, uint32_t *dstlen)
{
int ret;
if (*dstlen <= STREAM_END_SPACE)
return -1;
mutex_lock(&deflate_mutex);
if (Z_OK != zlib_deflateInit(&def_strm, 3)) {
pr_warn("deflateInit failed\n");
mutex_unlock(&deflate_mutex);
return -1;
}
def_strm.next_in = data_in;
def_strm.total_in = 0;
def_strm.next_out = cpage_out;
def_strm.total_out = 0;
while (def_strm.total_out < *dstlen - STREAM_END_SPACE && def_strm.total_in < *sourcelen) {
def_strm.avail_out = *dstlen - (def_strm.total_out + STREAM_END_SPACE);
def_strm.avail_in = min_t(unsigned long,
(*sourcelen-def_strm.total_in), def_strm.avail_out);
jffs2_dbg(1, "calling deflate with avail_in %ld, avail_out %ld\n",
def_strm.avail_in, def_strm.avail_out);
ret = zlib_deflate(&def_strm, Z_PARTIAL_FLUSH);
jffs2_dbg(1, "deflate returned with avail_in %ld, avail_out %ld, total_in %ld, total_out %ld\n",
def_strm.avail_in, def_strm.avail_out,
def_strm.total_in, def_strm.total_out);
if (ret != Z_OK) {
jffs2_dbg(1, "deflate in loop returned %d\n", ret);
zlib_deflateEnd(&def_strm);
mutex_unlock(&deflate_mutex);
return -1;
}
}
def_strm.avail_out += STREAM_END_SPACE;
def_strm.avail_in = 0;
ret = zlib_deflate(&def_strm, Z_FINISH);
zlib_deflateEnd(&def_strm);
if (ret != Z_STREAM_END) {
jffs2_dbg(1, "final deflate returned %d\n", ret);
ret = -1;
goto out;
}
if (def_strm.total_out >= def_strm.total_in) {
jffs2_dbg(1, "zlib compressed %ld bytes into %ld; failing\n",
def_strm.total_in, def_strm.total_out);
ret = -1;
goto out;
}
jffs2_dbg(1, "zlib compressed %ld bytes into %ld\n",
def_strm.total_in, def_strm.total_out);
*dstlen = def_strm.total_out;
*sourcelen = def_strm.total_in;
ret = 0;
out:
mutex_unlock(&deflate_mutex);
return ret;
}
static int jffs2_zlib_decompress(unsigned char *data_in,
unsigned char *cpage_out,
uint32_t srclen, uint32_t destlen)
{
int ret;
int wbits = MAX_WBITS;
mutex_lock(&inflate_mutex);
inf_strm.next_in = data_in;
inf_strm.avail_in = srclen;
inf_strm.total_in = 0;
inf_strm.next_out = cpage_out;
inf_strm.avail_out = destlen;
inf_strm.total_out = 0;
/* If it's deflate, and it's got no preset dictionary, then
we can tell zlib to skip the adler32 check. */
if (srclen > 2 && !(data_in[1] & PRESET_DICT) &&
((data_in[0] & 0x0f) == Z_DEFLATED) &&
!(((data_in[0]<<8) + data_in[1]) % 31)) {
jffs2_dbg(2, "inflate skipping adler32\n");
wbits = -((data_in[0] >> 4) + 8);
inf_strm.next_in += 2;
inf_strm.avail_in -= 2;
} else {
/* Let this remain D1 for now -- it should never happen */
jffs2_dbg(1, "inflate not skipping adler32\n");
}
if (Z_OK != zlib_inflateInit2(&inf_strm, wbits)) {
pr_warn("inflateInit failed\n");
mutex_unlock(&inflate_mutex);
return 1;
}
while((ret = zlib_inflate(&inf_strm, Z_FINISH)) == Z_OK)
;
if (ret != Z_STREAM_END) {
pr_notice("inflate returned %d\n", ret);
}
zlib_inflateEnd(&inf_strm);
mutex_unlock(&inflate_mutex);
return 0;
}
static struct jffs2_compressor jffs2_zlib_comp = {
.priority = JFFS2_ZLIB_PRIORITY,
.name = "zlib",
.compr = JFFS2_COMPR_ZLIB,
.compress = &jffs2_zlib_compress,
.decompress = &jffs2_zlib_decompress,
#ifdef JFFS2_ZLIB_DISABLED
.disabled = 1,
#else
.disabled = 0,
#endif
};
int __init jffs2_zlib_init(void)
{
int ret;
ret = alloc_workspaces();
if (ret)
return ret;
ret = jffs2_register_compressor(&jffs2_zlib_comp);
if (ret)
free_workspaces();
return ret;
}
void jffs2_zlib_exit(void)
{
jffs2_unregister_compressor(&jffs2_zlib_comp);
free_workspaces();
}