1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (c) 2013
4*4882a593Smuzhiyun * Phillip Lougher <phillip@squashfs.org.uk>
5*4882a593Smuzhiyun */
6*4882a593Smuzhiyun
7*4882a593Smuzhiyun #include <linux/types.h>
8*4882a593Smuzhiyun #include <linux/mutex.h>
9*4882a593Smuzhiyun #include <linux/slab.h>
10*4882a593Smuzhiyun #include <linux/bio.h>
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun #include "squashfs_fs.h"
13*4882a593Smuzhiyun #include "squashfs_fs_sb.h"
14*4882a593Smuzhiyun #include "decompressor.h"
15*4882a593Smuzhiyun #include "squashfs.h"
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun /*
18*4882a593Smuzhiyun * This file implements single-threaded decompression in the
19*4882a593Smuzhiyun * decompressor framework
20*4882a593Smuzhiyun */
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun struct squashfs_stream {
23*4882a593Smuzhiyun void *stream;
24*4882a593Smuzhiyun struct mutex mutex;
25*4882a593Smuzhiyun };
26*4882a593Smuzhiyun
squashfs_decompressor_create(struct squashfs_sb_info * msblk,void * comp_opts)27*4882a593Smuzhiyun void *squashfs_decompressor_create(struct squashfs_sb_info *msblk,
28*4882a593Smuzhiyun void *comp_opts)
29*4882a593Smuzhiyun {
30*4882a593Smuzhiyun struct squashfs_stream *stream;
31*4882a593Smuzhiyun int err = -ENOMEM;
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun stream = kmalloc(sizeof(*stream), GFP_KERNEL);
34*4882a593Smuzhiyun if (stream == NULL)
35*4882a593Smuzhiyun goto out;
36*4882a593Smuzhiyun
37*4882a593Smuzhiyun stream->stream = msblk->decompressor->init(msblk, comp_opts);
38*4882a593Smuzhiyun if (IS_ERR(stream->stream)) {
39*4882a593Smuzhiyun err = PTR_ERR(stream->stream);
40*4882a593Smuzhiyun goto out;
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun kfree(comp_opts);
44*4882a593Smuzhiyun mutex_init(&stream->mutex);
45*4882a593Smuzhiyun return stream;
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun out:
48*4882a593Smuzhiyun kfree(stream);
49*4882a593Smuzhiyun return ERR_PTR(err);
50*4882a593Smuzhiyun }
51*4882a593Smuzhiyun
squashfs_decompressor_destroy(struct squashfs_sb_info * msblk)52*4882a593Smuzhiyun void squashfs_decompressor_destroy(struct squashfs_sb_info *msblk)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun struct squashfs_stream *stream = msblk->stream;
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun if (stream) {
57*4882a593Smuzhiyun msblk->decompressor->free(stream->stream);
58*4882a593Smuzhiyun kfree(stream);
59*4882a593Smuzhiyun }
60*4882a593Smuzhiyun }
61*4882a593Smuzhiyun
squashfs_decompress(struct squashfs_sb_info * msblk,struct bio * bio,int offset,int length,struct squashfs_page_actor * output)62*4882a593Smuzhiyun int squashfs_decompress(struct squashfs_sb_info *msblk, struct bio *bio,
63*4882a593Smuzhiyun int offset, int length,
64*4882a593Smuzhiyun struct squashfs_page_actor *output)
65*4882a593Smuzhiyun {
66*4882a593Smuzhiyun int res;
67*4882a593Smuzhiyun struct squashfs_stream *stream = msblk->stream;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun mutex_lock(&stream->mutex);
70*4882a593Smuzhiyun res = msblk->decompressor->decompress(msblk, stream->stream, bio,
71*4882a593Smuzhiyun offset, length, output);
72*4882a593Smuzhiyun mutex_unlock(&stream->mutex);
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun if (res < 0)
75*4882a593Smuzhiyun ERROR("%s decompression failed, data probably corrupt\n",
76*4882a593Smuzhiyun msblk->decompressor->name);
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun return res;
79*4882a593Smuzhiyun }
80*4882a593Smuzhiyun
squashfs_max_decompressors(void)81*4882a593Smuzhiyun int squashfs_max_decompressors(void)
82*4882a593Smuzhiyun {
83*4882a593Smuzhiyun return 1;
84*4882a593Smuzhiyun }
85