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1/*
2 * Copyright (c) 2013, 2014
3 * Phillip Lougher <phillip@squashfs.org.uk>
4 *
5 * This work is licensed under the terms of the GNU GPL, version 2. See
6 * the COPYING file in the top-level directory.
7 */
8
9#include <linux/buffer_head.h>
10#include <linux/mutex.h>
11#include <linux/slab.h>
12#include <linux/vmalloc.h>
13#include <linux/lz4.h>
14
15#include "squashfs_fs.h"
16#include "squashfs_fs_sb.h"
17#include "squashfs.h"
18#include "decompressor.h"
19#include "page_actor.h"
20
21#define LZ4_LEGACY 1
22
23struct lz4_comp_opts {
24 __le32 version;
25 __le32 flags;
26};
27
28struct squashfs_lz4 {
29 void *input;
30 void *output;
31};
32
33
34static void *lz4_comp_opts(struct squashfs_sb_info *msblk,
35 void *buff, int len)
36{
37 struct lz4_comp_opts *comp_opts = buff;
38
39 /* LZ4 compressed filesystems always have compression options */
40 if (comp_opts == NULL || len < sizeof(*comp_opts))
41 return ERR_PTR(-EIO);
42
43 if (le32_to_cpu(comp_opts->version) != LZ4_LEGACY) {
44 /* LZ4 format currently used by the kernel is the 'legacy'
45 * format */
46 ERROR("Unknown LZ4 version\n");
47 return ERR_PTR(-EINVAL);
48 }
49
50 return NULL;
51}
52
53
54static void *lz4_init(struct squashfs_sb_info *msblk, void *buff)
55{
56 int block_size = max_t(int, msblk->block_size, SQUASHFS_METADATA_SIZE);
57 struct squashfs_lz4 *stream;
58
59 stream = kzalloc(sizeof(*stream), GFP_KERNEL);
60 if (stream == NULL)
61 goto failed;
62 stream->input = vmalloc(block_size);
63 if (stream->input == NULL)
64 goto failed2;
65 stream->output = vmalloc(block_size);
66 if (stream->output == NULL)
67 goto failed3;
68
69 return stream;
70
71failed3:
72 vfree(stream->input);
73failed2:
74 kfree(stream);
75failed:
76 ERROR("Failed to initialise LZ4 decompressor\n");
77 return ERR_PTR(-ENOMEM);
78}
79
80
81static void lz4_free(void *strm)
82{
83 struct squashfs_lz4 *stream = strm;
84
85 if (stream) {
86 vfree(stream->input);
87 vfree(stream->output);
88 }
89 kfree(stream);
90}
91
92
93static int lz4_uncompress(struct squashfs_sb_info *msblk, void *strm,
94 struct buffer_head **bh, int b, int offset, int length,
95 struct squashfs_page_actor *output)
96{
97 struct squashfs_lz4 *stream = strm;
98 void *buff = stream->input, *data;
99 int avail, i, bytes = length, res;
100 size_t dest_len = output->length;
101
102 for (i = 0; i < b; i++) {
103 avail = min(bytes, msblk->devblksize - offset);
104 memcpy(buff, bh[i]->b_data + offset, avail);
105 buff += avail;
106 bytes -= avail;
107 offset = 0;
108 put_bh(bh[i]);
109 }
110
111 res = lz4_decompress_unknownoutputsize(stream->input, length,
112 stream->output, &dest_len);
113 if (res)
114 return -EIO;
115
116 bytes = dest_len;
117 data = squashfs_first_page(output);
118 buff = stream->output;
119 while (data) {
120 if (bytes <= PAGE_SIZE) {
121 memcpy(data, buff, bytes);
122 break;
123 }
124 memcpy(data, buff, PAGE_SIZE);
125 buff += PAGE_SIZE;
126 bytes -= PAGE_SIZE;
127 data = squashfs_next_page(output);
128 }
129 squashfs_finish_page(output);
130
131 return dest_len;
132}
133
134const struct squashfs_decompressor squashfs_lz4_comp_ops = {
135 .init = lz4_init,
136 .comp_opts = lz4_comp_opts,
137 .free = lz4_free,
138 .decompress = lz4_uncompress,
139 .id = LZ4_COMPRESSION,
140 .name = "lz4",
141 .supported = 1
142};
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2013, 2014
4 * Phillip Lougher <phillip@squashfs.org.uk>
5 */
6
7#include <linux/bio.h>
8#include <linux/mutex.h>
9#include <linux/slab.h>
10#include <linux/vmalloc.h>
11#include <linux/lz4.h>
12
13#include "squashfs_fs.h"
14#include "squashfs_fs_sb.h"
15#include "squashfs.h"
16#include "decompressor.h"
17#include "page_actor.h"
18
19#define LZ4_LEGACY 1
20
21struct lz4_comp_opts {
22 __le32 version;
23 __le32 flags;
24};
25
26struct squashfs_lz4 {
27 void *input;
28 void *output;
29};
30
31
32static void *lz4_comp_opts(struct squashfs_sb_info *msblk,
33 void *buff, int len)
34{
35 struct lz4_comp_opts *comp_opts = buff;
36
37 /* LZ4 compressed filesystems always have compression options */
38 if (comp_opts == NULL || len < sizeof(*comp_opts))
39 return ERR_PTR(-EIO);
40
41 if (le32_to_cpu(comp_opts->version) != LZ4_LEGACY) {
42 /* LZ4 format currently used by the kernel is the 'legacy'
43 * format */
44 ERROR("Unknown LZ4 version\n");
45 return ERR_PTR(-EINVAL);
46 }
47
48 return NULL;
49}
50
51
52static void *lz4_init(struct squashfs_sb_info *msblk, void *buff)
53{
54 int block_size = max_t(int, msblk->block_size, SQUASHFS_METADATA_SIZE);
55 struct squashfs_lz4 *stream;
56
57 stream = kzalloc(sizeof(*stream), GFP_KERNEL);
58 if (stream == NULL)
59 goto failed;
60 stream->input = vmalloc(block_size);
61 if (stream->input == NULL)
62 goto failed2;
63 stream->output = vmalloc(block_size);
64 if (stream->output == NULL)
65 goto failed3;
66
67 return stream;
68
69failed3:
70 vfree(stream->input);
71failed2:
72 kfree(stream);
73failed:
74 ERROR("Failed to initialise LZ4 decompressor\n");
75 return ERR_PTR(-ENOMEM);
76}
77
78
79static void lz4_free(void *strm)
80{
81 struct squashfs_lz4 *stream = strm;
82
83 if (stream) {
84 vfree(stream->input);
85 vfree(stream->output);
86 }
87 kfree(stream);
88}
89
90
91static int lz4_uncompress(struct squashfs_sb_info *msblk, void *strm,
92 struct bio *bio, int offset, int length,
93 struct squashfs_page_actor *output)
94{
95 struct bvec_iter_all iter_all = {};
96 struct bio_vec *bvec = bvec_init_iter_all(&iter_all);
97 struct squashfs_lz4 *stream = strm;
98 void *buff = stream->input, *data;
99 int bytes = length, res;
100
101 while (bio_next_segment(bio, &iter_all)) {
102 int avail = min(bytes, ((int)bvec->bv_len) - offset);
103
104 data = page_address(bvec->bv_page) + bvec->bv_offset;
105 memcpy(buff, data + offset, avail);
106 buff += avail;
107 bytes -= avail;
108 offset = 0;
109 }
110
111 res = LZ4_decompress_safe(stream->input, stream->output,
112 length, output->length);
113
114 if (res < 0)
115 return -EIO;
116
117 bytes = res;
118 data = squashfs_first_page(output);
119 buff = stream->output;
120 while (data) {
121 if (bytes <= PAGE_SIZE) {
122 memcpy(data, buff, bytes);
123 break;
124 }
125 memcpy(data, buff, PAGE_SIZE);
126 buff += PAGE_SIZE;
127 bytes -= PAGE_SIZE;
128 data = squashfs_next_page(output);
129 }
130 squashfs_finish_page(output);
131
132 return res;
133}
134
135const struct squashfs_decompressor squashfs_lz4_comp_ops = {
136 .init = lz4_init,
137 .comp_opts = lz4_comp_opts,
138 .free = lz4_free,
139 .decompress = lz4_uncompress,
140 .id = LZ4_COMPRESSION,
141 .name = "lz4",
142 .supported = 1
143};