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Commit | Line | Data |
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3c56521b | 1 | /* |
585d0ed9 | 2 | * QEMU Block driver for CLOOP images |
5fafdf24 | 3 | * |
3c56521b | 4 | * Copyright (c) 2004 Johannes E. Schindelin |
5fafdf24 | 5 | * |
3c56521b FB |
6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
7 | * of this software and associated documentation files (the "Software"), to deal | |
8 | * in the Software without restriction, including without limitation the rights | |
9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
10 | * copies of the Software, and to permit persons to whom the Software is | |
11 | * furnished to do so, subject to the following conditions: | |
12 | * | |
13 | * The above copyright notice and this permission notice shall be included in | |
14 | * all copies or substantial portions of the Software. | |
15 | * | |
16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
22 | * THE SOFTWARE. | |
23 | */ | |
80c71a24 | 24 | #include "qemu/osdep.h" |
da34e65c | 25 | #include "qapi/error.h" |
398e6ad0 | 26 | #include "qemu/error-report.h" |
faf07963 | 27 | #include "qemu-common.h" |
737e150e | 28 | #include "block/block_int.h" |
1de7afc9 | 29 | #include "qemu/module.h" |
58369e22 | 30 | #include "qemu/bswap.h" |
3c56521b FB |
31 | #include <zlib.h> |
32 | ||
d65f97a8 SH |
33 | /* Maximum compressed block size */ |
34 | #define MAX_BLOCK_SIZE (64 * 1024 * 1024) | |
35 | ||
3c56521b | 36 | typedef struct BDRVCloopState { |
848c66e8 | 37 | CoMutex lock; |
3c56521b FB |
38 | uint32_t block_size; |
39 | uint32_t n_blocks; | |
5b47b7c3 | 40 | uint64_t *offsets; |
3c56521b FB |
41 | uint32_t sectors_per_block; |
42 | uint32_t current_block; | |
28a5c9c8 FB |
43 | uint8_t *compressed_block; |
44 | uint8_t *uncompressed_block; | |
3c56521b FB |
45 | z_stream zstream; |
46 | } BDRVCloopState; | |
47 | ||
48 | static int cloop_probe(const uint8_t *buf, int buf_size, const char *filename) | |
49 | { | |
5b47b7c3 DXW |
50 | const char *magic_version_2_0 = "#!/bin/sh\n" |
51 | "#V2.0 Format\n" | |
52 | "modprobe cloop file=$0 && mount -r -t iso9660 /dev/cloop $1\n"; | |
53 | int length = strlen(magic_version_2_0); | |
54 | if (length > buf_size) { | |
55 | length = buf_size; | |
56 | } | |
57 | if (!memcmp(magic_version_2_0, buf, length)) { | |
58 | return 2; | |
59 | } | |
3c56521b FB |
60 | return 0; |
61 | } | |
62 | ||
015a1036 HR |
63 | static int cloop_open(BlockDriverState *bs, QDict *options, int flags, |
64 | Error **errp) | |
3c56521b FB |
65 | { |
66 | BDRVCloopState *s = bs->opaque; | |
5b47b7c3 | 67 | uint32_t offsets_size, max_compressed_block_size = 1, i; |
1a60657f | 68 | int ret; |
3c56521b | 69 | |
eaa2410f KW |
70 | ret = bdrv_apply_auto_read_only(bs, NULL, errp); |
71 | if (ret < 0) { | |
72 | return ret; | |
73 | } | |
74 | ||
4e4bf5c4 KW |
75 | bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, |
76 | false, errp); | |
77 | if (!bs->file) { | |
78 | return -EINVAL; | |
79 | } | |
80 | ||
3c56521b | 81 | /* read header */ |
cf2ab8fc | 82 | ret = bdrv_pread(bs->file, 128, &s->block_size, 4); |
1a60657f KW |
83 | if (ret < 0) { |
84 | return ret; | |
3c56521b | 85 | } |
c94304be | 86 | s->block_size = be32_to_cpu(s->block_size); |
d65f97a8 | 87 | if (s->block_size % 512) { |
370e6816 | 88 | error_setg(errp, "block_size %" PRIu32 " must be a multiple of 512", |
d65f97a8 SH |
89 | s->block_size); |
90 | return -EINVAL; | |
91 | } | |
92 | if (s->block_size == 0) { | |
93 | error_setg(errp, "block_size cannot be zero"); | |
94 | return -EINVAL; | |
95 | } | |
96 | ||
97 | /* cloop's create_compressed_fs.c warns about block sizes beyond 256 KB but | |
98 | * we can accept more. Prevent ridiculous values like 4 GB - 1 since we | |
99 | * need a buffer this big. | |
100 | */ | |
101 | if (s->block_size > MAX_BLOCK_SIZE) { | |
370e6816 | 102 | error_setg(errp, "block_size %" PRIu32 " must be %u MB or less", |
d65f97a8 SH |
103 | s->block_size, |
104 | MAX_BLOCK_SIZE / (1024 * 1024)); | |
105 | return -EINVAL; | |
106 | } | |
c94304be | 107 | |
cf2ab8fc | 108 | ret = bdrv_pread(bs->file, 128 + 4, &s->n_blocks, 4); |
1a60657f KW |
109 | if (ret < 0) { |
110 | return ret; | |
c94304be CH |
111 | } |
112 | s->n_blocks = be32_to_cpu(s->n_blocks); | |
3c56521b FB |
113 | |
114 | /* read offsets */ | |
42d43d35 | 115 | if (s->n_blocks > (UINT32_MAX - 1) / sizeof(uint64_t)) { |
509a41ba | 116 | /* Prevent integer overflow */ |
370e6816 | 117 | error_setg(errp, "n_blocks %" PRIu32 " must be %zu or less", |
509a41ba | 118 | s->n_blocks, |
42d43d35 | 119 | (UINT32_MAX - 1) / sizeof(uint64_t)); |
509a41ba SH |
120 | return -EINVAL; |
121 | } | |
42d43d35 | 122 | offsets_size = (s->n_blocks + 1) * sizeof(uint64_t); |
7b103b36 SH |
123 | if (offsets_size > 512 * 1024 * 1024) { |
124 | /* Prevent ridiculous offsets_size which causes memory allocation to | |
125 | * fail or overflows bdrv_pread() size. In practice the 512 MB | |
126 | * offsets[] limit supports 16 TB images at 256 KB block size. | |
127 | */ | |
128 | error_setg(errp, "image requires too many offsets, " | |
129 | "try increasing block size"); | |
130 | return -EINVAL; | |
131 | } | |
4ae7a52e KW |
132 | |
133 | s->offsets = g_try_malloc(offsets_size); | |
134 | if (s->offsets == NULL) { | |
135 | error_setg(errp, "Could not allocate offsets table"); | |
136 | return -ENOMEM; | |
137 | } | |
1a60657f | 138 | |
cf2ab8fc | 139 | ret = bdrv_pread(bs->file, 128 + 4 + 4, s->offsets, offsets_size); |
1a60657f KW |
140 | if (ret < 0) { |
141 | goto fail; | |
c94304be | 142 | } |
1a60657f | 143 | |
42d43d35 | 144 | for (i = 0; i < s->n_blocks + 1; i++) { |
f56b9bc3 SH |
145 | uint64_t size; |
146 | ||
5b47b7c3 | 147 | s->offsets[i] = be64_to_cpu(s->offsets[i]); |
f56b9bc3 SH |
148 | if (i == 0) { |
149 | continue; | |
150 | } | |
151 | ||
152 | if (s->offsets[i] < s->offsets[i - 1]) { | |
153 | error_setg(errp, "offsets not monotonically increasing at " | |
370e6816 | 154 | "index %" PRIu32 ", image file is corrupt", i); |
f56b9bc3 SH |
155 | ret = -EINVAL; |
156 | goto fail; | |
157 | } | |
158 | ||
159 | size = s->offsets[i] - s->offsets[i - 1]; | |
160 | ||
161 | /* Compressed blocks should be smaller than the uncompressed block size | |
162 | * but maybe compression performed poorly so the compressed block is | |
163 | * actually bigger. Clamp down on unrealistic values to prevent | |
164 | * ridiculous s->compressed_block allocation. | |
165 | */ | |
166 | if (size > 2 * MAX_BLOCK_SIZE) { | |
370e6816 SH |
167 | error_setg(errp, "invalid compressed block size at index %" PRIu32 |
168 | ", image file is corrupt", i); | |
f56b9bc3 SH |
169 | ret = -EINVAL; |
170 | goto fail; | |
171 | } | |
172 | ||
173 | if (size > max_compressed_block_size) { | |
174 | max_compressed_block_size = size; | |
5b47b7c3 | 175 | } |
3c56521b FB |
176 | } |
177 | ||
178 | /* initialize zlib engine */ | |
4ae7a52e KW |
179 | s->compressed_block = g_try_malloc(max_compressed_block_size + 1); |
180 | if (s->compressed_block == NULL) { | |
181 | error_setg(errp, "Could not allocate compressed_block"); | |
182 | ret = -ENOMEM; | |
183 | goto fail; | |
184 | } | |
185 | ||
186 | s->uncompressed_block = g_try_malloc(s->block_size); | |
187 | if (s->uncompressed_block == NULL) { | |
188 | error_setg(errp, "Could not allocate uncompressed_block"); | |
189 | ret = -ENOMEM; | |
190 | goto fail; | |
191 | } | |
192 | ||
5b47b7c3 | 193 | if (inflateInit(&s->zstream) != Z_OK) { |
1a60657f KW |
194 | ret = -EINVAL; |
195 | goto fail; | |
5b47b7c3 DXW |
196 | } |
197 | s->current_block = s->n_blocks; | |
3b46e624 | 198 | |
3c56521b | 199 | s->sectors_per_block = s->block_size/512; |
5b47b7c3 | 200 | bs->total_sectors = s->n_blocks * s->sectors_per_block; |
848c66e8 | 201 | qemu_co_mutex_init(&s->lock); |
3c56521b | 202 | return 0; |
c94304be | 203 | |
1a60657f KW |
204 | fail: |
205 | g_free(s->offsets); | |
206 | g_free(s->compressed_block); | |
207 | g_free(s->uncompressed_block); | |
208 | return ret; | |
3c56521b FB |
209 | } |
210 | ||
a6506481 EB |
211 | static void cloop_refresh_limits(BlockDriverState *bs, Error **errp) |
212 | { | |
a5b8dd2c | 213 | bs->bl.request_alignment = BDRV_SECTOR_SIZE; /* No sub-sector I/O */ |
a6506481 EB |
214 | } |
215 | ||
20be49e4 | 216 | static inline int cloop_read_block(BlockDriverState *bs, int block_num) |
3c56521b | 217 | { |
20be49e4 CH |
218 | BDRVCloopState *s = bs->opaque; |
219 | ||
5b47b7c3 DXW |
220 | if (s->current_block != block_num) { |
221 | int ret; | |
222 | uint32_t bytes = s->offsets[block_num + 1] - s->offsets[block_num]; | |
3b46e624 | 223 | |
cf2ab8fc | 224 | ret = bdrv_pread(bs->file, s->offsets[block_num], |
9a4f4c31 | 225 | s->compressed_block, bytes); |
5b47b7c3 | 226 | if (ret != bytes) { |
3c56521b | 227 | return -1; |
5b47b7c3 DXW |
228 | } |
229 | ||
230 | s->zstream.next_in = s->compressed_block; | |
231 | s->zstream.avail_in = bytes; | |
232 | s->zstream.next_out = s->uncompressed_block; | |
233 | s->zstream.avail_out = s->block_size; | |
234 | ret = inflateReset(&s->zstream); | |
235 | if (ret != Z_OK) { | |
236 | return -1; | |
237 | } | |
238 | ret = inflate(&s->zstream, Z_FINISH); | |
239 | if (ret != Z_STREAM_END || s->zstream.total_out != s->block_size) { | |
240 | return -1; | |
241 | } | |
5fafdf24 | 242 | |
5b47b7c3 | 243 | s->current_block = block_num; |
3c56521b FB |
244 | } |
245 | return 0; | |
246 | } | |
247 | ||
5cd23081 KW |
248 | static int coroutine_fn |
249 | cloop_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes, | |
250 | QEMUIOVector *qiov, int flags) | |
3c56521b FB |
251 | { |
252 | BDRVCloopState *s = bs->opaque; | |
5cd23081 KW |
253 | uint64_t sector_num = offset >> BDRV_SECTOR_BITS; |
254 | int nb_sectors = bytes >> BDRV_SECTOR_BITS; | |
255 | int ret, i; | |
256 | ||
257 | assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0); | |
258 | assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); | |
259 | ||
260 | qemu_co_mutex_lock(&s->lock); | |
3c56521b | 261 | |
5b47b7c3 | 262 | for (i = 0; i < nb_sectors; i++) { |
5cd23081 | 263 | void *data; |
5b47b7c3 DXW |
264 | uint32_t sector_offset_in_block = |
265 | ((sector_num + i) % s->sectors_per_block), | |
266 | block_num = (sector_num + i) / s->sectors_per_block; | |
267 | if (cloop_read_block(bs, block_num) != 0) { | |
5cd23081 KW |
268 | ret = -EIO; |
269 | goto fail; | |
5b47b7c3 | 270 | } |
5cd23081 KW |
271 | |
272 | data = s->uncompressed_block + sector_offset_in_block * 512; | |
273 | qemu_iovec_from_buf(qiov, i * 512, data, 512); | |
3c56521b | 274 | } |
3c56521b | 275 | |
5cd23081 KW |
276 | ret = 0; |
277 | fail: | |
2914caa0 | 278 | qemu_co_mutex_unlock(&s->lock); |
5cd23081 | 279 | |
2914caa0 PB |
280 | return ret; |
281 | } | |
282 | ||
3c56521b FB |
283 | static void cloop_close(BlockDriverState *bs) |
284 | { | |
285 | BDRVCloopState *s = bs->opaque; | |
42d43d35 | 286 | g_free(s->offsets); |
756f51e4 DXW |
287 | g_free(s->compressed_block); |
288 | g_free(s->uncompressed_block); | |
3c56521b FB |
289 | inflateEnd(&s->zstream); |
290 | } | |
291 | ||
5efa9d5a | 292 | static BlockDriver bdrv_cloop = { |
5b47b7c3 DXW |
293 | .format_name = "cloop", |
294 | .instance_size = sizeof(BDRVCloopState), | |
295 | .bdrv_probe = cloop_probe, | |
296 | .bdrv_open = cloop_open, | |
862f215f | 297 | .bdrv_child_perm = bdrv_format_default_perms, |
a6506481 | 298 | .bdrv_refresh_limits = cloop_refresh_limits, |
5cd23081 | 299 | .bdrv_co_preadv = cloop_co_preadv, |
5b47b7c3 | 300 | .bdrv_close = cloop_close, |
3c56521b | 301 | }; |
5efa9d5a AL |
302 | |
303 | static void bdrv_cloop_init(void) | |
304 | { | |
305 | bdrv_register(&bdrv_cloop); | |
306 | } | |
307 | ||
308 | block_init(bdrv_cloop_init); |