136 строки
3.1 KiB
C
136 строки
3.1 KiB
C
/*
|
|
* Squashfs - a compressed read only filesystem for Linux
|
|
*
|
|
* Copyright (c) 2010 LG Electronics
|
|
* Chan Jeong <chan.jeong@lge.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2,
|
|
* or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
|
|
*
|
|
* lzo_wrapper.c
|
|
*/
|
|
|
|
#include <linux/mutex.h>
|
|
#include <linux/buffer_head.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/lzo.h>
|
|
|
|
#include "squashfs_fs.h"
|
|
#include "squashfs_fs_sb.h"
|
|
#include "squashfs.h"
|
|
#include "decompressor.h"
|
|
|
|
struct squashfs_lzo {
|
|
void *input;
|
|
void *output;
|
|
};
|
|
|
|
static void *lzo_init(struct squashfs_sb_info *msblk)
|
|
{
|
|
int block_size = max_t(int, msblk->block_size, SQUASHFS_METADATA_SIZE);
|
|
|
|
struct squashfs_lzo *stream = kzalloc(sizeof(*stream), GFP_KERNEL);
|
|
if (stream == NULL)
|
|
goto failed;
|
|
stream->input = vmalloc(block_size);
|
|
if (stream->input == NULL)
|
|
goto failed;
|
|
stream->output = vmalloc(block_size);
|
|
if (stream->output == NULL)
|
|
goto failed2;
|
|
|
|
return stream;
|
|
|
|
failed2:
|
|
vfree(stream->input);
|
|
failed:
|
|
ERROR("Failed to allocate lzo workspace\n");
|
|
kfree(stream);
|
|
return NULL;
|
|
}
|
|
|
|
|
|
static void lzo_free(void *strm)
|
|
{
|
|
struct squashfs_lzo *stream = strm;
|
|
|
|
if (stream) {
|
|
vfree(stream->input);
|
|
vfree(stream->output);
|
|
}
|
|
kfree(stream);
|
|
}
|
|
|
|
|
|
static int lzo_uncompress(struct squashfs_sb_info *msblk, void **buffer,
|
|
struct buffer_head **bh, int b, int offset, int length, int srclength,
|
|
int pages)
|
|
{
|
|
struct squashfs_lzo *stream = msblk->stream;
|
|
void *buff = stream->input;
|
|
int avail, i, bytes = length, res;
|
|
size_t out_len = srclength;
|
|
|
|
mutex_lock(&msblk->read_data_mutex);
|
|
|
|
for (i = 0; i < b; i++) {
|
|
wait_on_buffer(bh[i]);
|
|
if (!buffer_uptodate(bh[i]))
|
|
goto block_release;
|
|
|
|
avail = min(bytes, msblk->devblksize - offset);
|
|
memcpy(buff, bh[i]->b_data + offset, avail);
|
|
buff += avail;
|
|
bytes -= avail;
|
|
offset = 0;
|
|
put_bh(bh[i]);
|
|
}
|
|
|
|
res = lzo1x_decompress_safe(stream->input, (size_t)length,
|
|
stream->output, &out_len);
|
|
if (res != LZO_E_OK)
|
|
goto failed;
|
|
|
|
res = bytes = (int)out_len;
|
|
for (i = 0, buff = stream->output; bytes && i < pages; i++) {
|
|
avail = min_t(int, bytes, PAGE_CACHE_SIZE);
|
|
memcpy(buffer[i], buff, avail);
|
|
buff += avail;
|
|
bytes -= avail;
|
|
}
|
|
|
|
mutex_unlock(&msblk->read_data_mutex);
|
|
return res;
|
|
|
|
block_release:
|
|
for (; i < b; i++)
|
|
put_bh(bh[i]);
|
|
|
|
failed:
|
|
mutex_unlock(&msblk->read_data_mutex);
|
|
|
|
ERROR("lzo decompression failed, data probably corrupt\n");
|
|
return -EIO;
|
|
}
|
|
|
|
const struct squashfs_decompressor squashfs_lzo_comp_ops = {
|
|
.init = lzo_init,
|
|
.free = lzo_free,
|
|
.decompress = lzo_uncompress,
|
|
.id = LZO_COMPRESSION,
|
|
.name = "lzo",
|
|
.supported = 1
|
|
};
|