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1/*
2 * Squashfs - a compressed read only filesystem for Linux
3 *
4 * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
5 * Phillip Lougher <phillip@squashfs.org.uk>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2,
10 * or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
20 *
21 * xz_wrapper.c
22 */
23
24
25#include <linux/mutex.h>
26#include <linux/buffer_head.h>
27#include <linux/slab.h>
28#include <linux/xz.h>
29#include <linux/bitops.h>
30
31#include "squashfs_fs.h"
32#include "squashfs_fs_sb.h"
33#include "squashfs.h"
34#include "decompressor.h"
35#include "page_actor.h"
36
37struct squashfs_xz {
38 struct xz_dec *state;
39 struct xz_buf buf;
40};
41
42struct disk_comp_opts {
43 __le32 dictionary_size;
44 __le32 flags;
45};
46
47struct comp_opts {
48 int dict_size;
49};
50
51static void *squashfs_xz_comp_opts(struct squashfs_sb_info *msblk,
52 void *buff, int len)
53{
54 struct disk_comp_opts *comp_opts = buff;
55 struct comp_opts *opts;
56 int err = 0, n;
57
58 opts = kmalloc(sizeof(*opts), GFP_KERNEL);
59 if (opts == NULL) {
60 err = -ENOMEM;
61 goto out2;
62 }
63
64 if (comp_opts) {
65 /* check compressor options are the expected length */
66 if (len < sizeof(*comp_opts)) {
67 err = -EIO;
68 goto out;
69 }
70
71 opts->dict_size = le32_to_cpu(comp_opts->dictionary_size);
72
73 /* the dictionary size should be 2^n or 2^n+2^(n+1) */
74 n = ffs(opts->dict_size) - 1;
75 if (opts->dict_size != (1 << n) && opts->dict_size != (1 << n) +
76 (1 << (n + 1))) {
77 err = -EIO;
78 goto out;
79 }
80 } else
81 /* use defaults */
82 opts->dict_size = max_t(int, msblk->block_size,
83 SQUASHFS_METADATA_SIZE);
84
85 return opts;
86
87out:
88 kfree(opts);
89out2:
90 return ERR_PTR(err);
91}
92
93
94static void *squashfs_xz_init(struct squashfs_sb_info *msblk, void *buff)
95{
96 struct comp_opts *comp_opts = buff;
97 struct squashfs_xz *stream;
98 int err;
99
100 stream = kmalloc(sizeof(*stream), GFP_KERNEL);
101 if (stream == NULL) {
102 err = -ENOMEM;
103 goto failed;
104 }
105
106 stream->state = xz_dec_init(XZ_PREALLOC, comp_opts->dict_size);
107 if (stream->state == NULL) {
108 kfree(stream);
109 err = -ENOMEM;
110 goto failed;
111 }
112
113 return stream;
114
115failed:
116 ERROR("Failed to initialise xz decompressor\n");
117 return ERR_PTR(err);
118}
119
120
121static void squashfs_xz_free(void *strm)
122{
123 struct squashfs_xz *stream = strm;
124
125 if (stream) {
126 xz_dec_end(stream->state);
127 kfree(stream);
128 }
129}
130
131
132static int squashfs_xz_uncompress(struct squashfs_sb_info *msblk, void *strm,
133 struct buffer_head **bh, int b, int offset, int length,
134 struct squashfs_page_actor *output)
135{
136 enum xz_ret xz_err;
137 int avail, total = 0, k = 0;
138 struct squashfs_xz *stream = strm;
139
140 xz_dec_reset(stream->state);
141 stream->buf.in_pos = 0;
142 stream->buf.in_size = 0;
143 stream->buf.out_pos = 0;
144 stream->buf.out_size = PAGE_SIZE;
145 stream->buf.out = squashfs_first_page(output);
146
147 do {
148 if (stream->buf.in_pos == stream->buf.in_size && k < b) {
149 avail = min(length, msblk->devblksize - offset);
150 length -= avail;
151 stream->buf.in = bh[k]->b_data + offset;
152 stream->buf.in_size = avail;
153 stream->buf.in_pos = 0;
154 offset = 0;
155 }
156
157 if (stream->buf.out_pos == stream->buf.out_size) {
158 stream->buf.out = squashfs_next_page(output);
159 if (stream->buf.out != NULL) {
160 stream->buf.out_pos = 0;
161 total += PAGE_SIZE;
162 }
163 }
164
165 xz_err = xz_dec_run(stream->state, &stream->buf);
166
167 if (stream->buf.in_pos == stream->buf.in_size && k < b)
168 put_bh(bh[k++]);
169 } while (xz_err == XZ_OK);
170
171 squashfs_finish_page(output);
172
173 if (xz_err != XZ_STREAM_END || k < b)
174 goto out;
175
176 return total + stream->buf.out_pos;
177
178out:
179 for (; k < b; k++)
180 put_bh(bh[k]);
181
182 return -EIO;
183}
184
185const struct squashfs_decompressor squashfs_xz_comp_ops = {
186 .init = squashfs_xz_init,
187 .comp_opts = squashfs_xz_comp_opts,
188 .free = squashfs_xz_free,
189 .decompress = squashfs_xz_uncompress,
190 .id = XZ_COMPRESSION,
191 .name = "xz",
192 .supported = 1
193};
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Squashfs - a compressed read only filesystem for Linux
4 *
5 * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
6 * Phillip Lougher <phillip@squashfs.org.uk>
7 *
8 * xz_wrapper.c
9 */
10
11
12#include <linux/mutex.h>
13#include <linux/bio.h>
14#include <linux/slab.h>
15#include <linux/xz.h>
16#include <linux/bitops.h>
17
18#include "squashfs_fs.h"
19#include "squashfs_fs_sb.h"
20#include "squashfs.h"
21#include "decompressor.h"
22#include "page_actor.h"
23
24struct squashfs_xz {
25 struct xz_dec *state;
26 struct xz_buf buf;
27};
28
29struct disk_comp_opts {
30 __le32 dictionary_size;
31 __le32 flags;
32};
33
34struct comp_opts {
35 int dict_size;
36};
37
38static void *squashfs_xz_comp_opts(struct squashfs_sb_info *msblk,
39 void *buff, int len)
40{
41 struct disk_comp_opts *comp_opts = buff;
42 struct comp_opts *opts;
43 int err = 0, n;
44
45 opts = kmalloc(sizeof(*opts), GFP_KERNEL);
46 if (opts == NULL) {
47 err = -ENOMEM;
48 goto out2;
49 }
50
51 if (comp_opts) {
52 /* check compressor options are the expected length */
53 if (len < sizeof(*comp_opts)) {
54 err = -EIO;
55 goto out;
56 }
57
58 opts->dict_size = le32_to_cpu(comp_opts->dictionary_size);
59
60 /* the dictionary size should be 2^n or 2^n+2^(n+1) */
61 n = ffs(opts->dict_size) - 1;
62 if (opts->dict_size != (1 << n) && opts->dict_size != (1 << n) +
63 (1 << (n + 1))) {
64 err = -EIO;
65 goto out;
66 }
67 } else
68 /* use defaults */
69 opts->dict_size = max_t(int, msblk->block_size,
70 SQUASHFS_METADATA_SIZE);
71
72 return opts;
73
74out:
75 kfree(opts);
76out2:
77 return ERR_PTR(err);
78}
79
80
81static void *squashfs_xz_init(struct squashfs_sb_info *msblk, void *buff)
82{
83 struct comp_opts *comp_opts = buff;
84 struct squashfs_xz *stream;
85 int err;
86
87 stream = kmalloc(sizeof(*stream), GFP_KERNEL);
88 if (stream == NULL) {
89 err = -ENOMEM;
90 goto failed;
91 }
92
93 stream->state = xz_dec_init(XZ_PREALLOC, comp_opts->dict_size);
94 if (stream->state == NULL) {
95 kfree(stream);
96 err = -ENOMEM;
97 goto failed;
98 }
99
100 return stream;
101
102failed:
103 ERROR("Failed to initialise xz decompressor\n");
104 return ERR_PTR(err);
105}
106
107
108static void squashfs_xz_free(void *strm)
109{
110 struct squashfs_xz *stream = strm;
111
112 if (stream) {
113 xz_dec_end(stream->state);
114 kfree(stream);
115 }
116}
117
118
119static int squashfs_xz_uncompress(struct squashfs_sb_info *msblk, void *strm,
120 struct bio *bio, int offset, int length,
121 struct squashfs_page_actor *output)
122{
123 struct bvec_iter_all iter_all = {};
124 struct bio_vec *bvec = bvec_init_iter_all(&iter_all);
125 int total = 0, error = 0;
126 struct squashfs_xz *stream = strm;
127
128 xz_dec_reset(stream->state);
129 stream->buf.in_pos = 0;
130 stream->buf.in_size = 0;
131 stream->buf.out_pos = 0;
132 stream->buf.out_size = PAGE_SIZE;
133 stream->buf.out = squashfs_first_page(output);
134
135 for (;;) {
136 enum xz_ret xz_err;
137
138 if (stream->buf.in_pos == stream->buf.in_size) {
139 const void *data;
140 int avail;
141
142 if (!bio_next_segment(bio, &iter_all)) {
143 /* XZ_STREAM_END must be reached. */
144 error = -EIO;
145 break;
146 }
147
148 avail = min(length, ((int)bvec->bv_len) - offset);
149 data = page_address(bvec->bv_page) + bvec->bv_offset;
150 length -= avail;
151 stream->buf.in = data + offset;
152 stream->buf.in_size = avail;
153 stream->buf.in_pos = 0;
154 offset = 0;
155 }
156
157 if (stream->buf.out_pos == stream->buf.out_size) {
158 stream->buf.out = squashfs_next_page(output);
159 if (stream->buf.out != NULL) {
160 stream->buf.out_pos = 0;
161 total += PAGE_SIZE;
162 }
163 }
164
165 xz_err = xz_dec_run(stream->state, &stream->buf);
166 if (xz_err == XZ_STREAM_END)
167 break;
168 if (xz_err != XZ_OK) {
169 error = -EIO;
170 break;
171 }
172 }
173
174 squashfs_finish_page(output);
175
176 return error ? error : total + stream->buf.out_pos;
177}
178
179const struct squashfs_decompressor squashfs_xz_comp_ops = {
180 .init = squashfs_xz_init,
181 .comp_opts = squashfs_xz_comp_opts,
182 .free = squashfs_xz_free,
183 .decompress = squashfs_xz_uncompress,
184 .id = XZ_COMPRESSION,
185 .name = "xz",
186 .supported = 1
187};