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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2013
4 * Phillip Lougher <phillip@squashfs.org.uk>
5 */
6
7#include <linux/types.h>
8#include <linux/mutex.h>
9#include <linux/slab.h>
10#include <linux/buffer_head.h>
11
12#include "squashfs_fs.h"
13#include "squashfs_fs_sb.h"
14#include "decompressor.h"
15#include "squashfs.h"
16
17/*
18 * This file implements single-threaded decompression in the
19 * decompressor framework
20 */
21
22struct squashfs_stream {
23 void *stream;
24 struct mutex mutex;
25};
26
27void *squashfs_decompressor_create(struct squashfs_sb_info *msblk,
28 void *comp_opts)
29{
30 struct squashfs_stream *stream;
31 int err = -ENOMEM;
32
33 stream = kmalloc(sizeof(*stream), GFP_KERNEL);
34 if (stream == NULL)
35 goto out;
36
37 stream->stream = msblk->decompressor->init(msblk, comp_opts);
38 if (IS_ERR(stream->stream)) {
39 err = PTR_ERR(stream->stream);
40 goto out;
41 }
42
43 kfree(comp_opts);
44 mutex_init(&stream->mutex);
45 return stream;
46
47out:
48 kfree(stream);
49 return ERR_PTR(err);
50}
51
52void squashfs_decompressor_destroy(struct squashfs_sb_info *msblk)
53{
54 struct squashfs_stream *stream = msblk->stream;
55
56 if (stream) {
57 msblk->decompressor->free(stream->stream);
58 kfree(stream);
59 }
60}
61
62int squashfs_decompress(struct squashfs_sb_info *msblk, struct buffer_head **bh,
63 int b, int offset, int length, struct squashfs_page_actor *output)
64{
65 int res;
66 struct squashfs_stream *stream = msblk->stream;
67
68 mutex_lock(&stream->mutex);
69 res = msblk->decompressor->decompress(msblk, stream->stream, bh, b,
70 offset, length, output);
71 mutex_unlock(&stream->mutex);
72
73 if (res < 0)
74 ERROR("%s decompression failed, data probably corrupt\n",
75 msblk->decompressor->name);
76
77 return res;
78}
79
80int squashfs_max_decompressors(void)
81{
82 return 1;
83}