mirror of
https://github.com/torvalds/linux.git
synced 2025-11-04 02:30:34 +02:00
6b81459c9c
Squashfs has stopped using buffers heads in 93e72b3c61
("squashfs: migrate from ll_rw_block usage to BIO").
Link: https://lkml.kernel.org/r/20230517071622.245151-1-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Reviewed-by: Phillip Lougher <phillip@squashfs.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
141 lines
3.2 KiB
C
141 lines
3.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Squashfs - a compressed read only filesystem for Linux
|
|
*
|
|
* Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
|
|
* Phillip Lougher <phillip@squashfs.org.uk>
|
|
*
|
|
* decompressor.c
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/slab.h>
|
|
|
|
#include "squashfs_fs.h"
|
|
#include "squashfs_fs_sb.h"
|
|
#include "decompressor.h"
|
|
#include "squashfs.h"
|
|
#include "page_actor.h"
|
|
|
|
/*
|
|
* This file (and decompressor.h) implements a decompressor framework for
|
|
* Squashfs, allowing multiple decompressors to be easily supported
|
|
*/
|
|
|
|
static const struct squashfs_decompressor squashfs_lzma_unsupported_comp_ops = {
|
|
NULL, NULL, NULL, NULL, LZMA_COMPRESSION, "lzma", 0
|
|
};
|
|
|
|
#ifndef CONFIG_SQUASHFS_LZ4
|
|
static const struct squashfs_decompressor squashfs_lz4_comp_ops = {
|
|
NULL, NULL, NULL, NULL, LZ4_COMPRESSION, "lz4", 0
|
|
};
|
|
#endif
|
|
|
|
#ifndef CONFIG_SQUASHFS_LZO
|
|
static const struct squashfs_decompressor squashfs_lzo_comp_ops = {
|
|
NULL, NULL, NULL, NULL, LZO_COMPRESSION, "lzo", 0
|
|
};
|
|
#endif
|
|
|
|
#ifndef CONFIG_SQUASHFS_XZ
|
|
static const struct squashfs_decompressor squashfs_xz_comp_ops = {
|
|
NULL, NULL, NULL, NULL, XZ_COMPRESSION, "xz", 0
|
|
};
|
|
#endif
|
|
|
|
#ifndef CONFIG_SQUASHFS_ZLIB
|
|
static const struct squashfs_decompressor squashfs_zlib_comp_ops = {
|
|
NULL, NULL, NULL, NULL, ZLIB_COMPRESSION, "zlib", 0
|
|
};
|
|
#endif
|
|
|
|
#ifndef CONFIG_SQUASHFS_ZSTD
|
|
static const struct squashfs_decompressor squashfs_zstd_comp_ops = {
|
|
NULL, NULL, NULL, NULL, ZSTD_COMPRESSION, "zstd", 0
|
|
};
|
|
#endif
|
|
|
|
static const struct squashfs_decompressor squashfs_unknown_comp_ops = {
|
|
NULL, NULL, NULL, NULL, 0, "unknown", 0
|
|
};
|
|
|
|
static const struct squashfs_decompressor *decompressor[] = {
|
|
&squashfs_zlib_comp_ops,
|
|
&squashfs_lz4_comp_ops,
|
|
&squashfs_lzo_comp_ops,
|
|
&squashfs_xz_comp_ops,
|
|
&squashfs_lzma_unsupported_comp_ops,
|
|
&squashfs_zstd_comp_ops,
|
|
&squashfs_unknown_comp_ops
|
|
};
|
|
|
|
|
|
const struct squashfs_decompressor *squashfs_lookup_decompressor(int id)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; decompressor[i]->id; i++)
|
|
if (id == decompressor[i]->id)
|
|
break;
|
|
|
|
return decompressor[i];
|
|
}
|
|
|
|
|
|
static void *get_comp_opts(struct super_block *sb, unsigned short flags)
|
|
{
|
|
struct squashfs_sb_info *msblk = sb->s_fs_info;
|
|
void *buffer = NULL, *comp_opts;
|
|
struct squashfs_page_actor *actor = NULL;
|
|
int length = 0;
|
|
|
|
/*
|
|
* Read decompressor specific options from file system if present
|
|
*/
|
|
if (SQUASHFS_COMP_OPTS(flags)) {
|
|
buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
|
|
if (buffer == NULL) {
|
|
comp_opts = ERR_PTR(-ENOMEM);
|
|
goto out;
|
|
}
|
|
|
|
actor = squashfs_page_actor_init(&buffer, 1, 0);
|
|
if (actor == NULL) {
|
|
comp_opts = ERR_PTR(-ENOMEM);
|
|
goto out;
|
|
}
|
|
|
|
length = squashfs_read_data(sb,
|
|
sizeof(struct squashfs_super_block), 0, NULL, actor);
|
|
|
|
if (length < 0) {
|
|
comp_opts = ERR_PTR(length);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
comp_opts = squashfs_comp_opts(msblk, buffer, length);
|
|
|
|
out:
|
|
kfree(actor);
|
|
kfree(buffer);
|
|
return comp_opts;
|
|
}
|
|
|
|
|
|
void *squashfs_decompressor_setup(struct super_block *sb, unsigned short flags)
|
|
{
|
|
struct squashfs_sb_info *msblk = sb->s_fs_info;
|
|
void *stream, *comp_opts = get_comp_opts(sb, flags);
|
|
|
|
if (IS_ERR(comp_opts))
|
|
return comp_opts;
|
|
|
|
stream = msblk->thread_ops->create(msblk, comp_opts);
|
|
if (IS_ERR(stream))
|
|
kfree(comp_opts);
|
|
|
|
return stream;
|
|
}
|