Revision 16d2fc00 block/cow.c
| b/block/cow.c | ||
|---|---|---|
| 64 | 64 |
struct cow_header_v2 cow_header; |
| 65 | 65 |
int bitmap_size; |
| 66 | 66 |
int64_t size; |
| 67 |
int ret; |
|
| 67 | 68 |
|
| 68 | 69 |
/* see if it is a cow image */ |
| 69 |
if (bdrv_pread(bs->file, 0, &cow_header, sizeof(cow_header)) != |
|
| 70 |
sizeof(cow_header)) {
|
|
| 70 |
ret = bdrv_pread(bs->file, 0, &cow_header, sizeof(cow_header)); |
|
| 71 |
if (ret < 0) {
|
|
| 72 |
goto fail; |
|
| 73 |
} |
|
| 74 |
|
|
| 75 |
if (be32_to_cpu(cow_header.magic) != COW_MAGIC) {
|
|
| 76 |
ret = -EINVAL; |
|
| 71 | 77 |
goto fail; |
| 72 | 78 |
} |
| 73 | 79 |
|
| 74 |
if (be32_to_cpu(cow_header.magic) != COW_MAGIC || |
|
| 75 |
be32_to_cpu(cow_header.version) != COW_VERSION) {
|
|
| 80 |
if (be32_to_cpu(cow_header.version) != COW_VERSION) {
|
|
| 81 |
char version[64]; |
|
| 82 |
snprintf(version, sizeof(version), |
|
| 83 |
"COW version %d", cow_header.version); |
|
| 84 |
qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE, |
|
| 85 |
bs->device_name, "cow", version); |
|
| 86 |
ret = -ENOTSUP; |
|
| 76 | 87 |
goto fail; |
| 77 | 88 |
} |
| 78 | 89 |
|
| ... | ... | |
| 88 | 99 |
qemu_co_mutex_init(&s->lock); |
| 89 | 100 |
return 0; |
| 90 | 101 |
fail: |
| 91 |
return -1;
|
|
| 102 |
return ret;
|
|
| 92 | 103 |
} |
| 93 | 104 |
|
| 94 | 105 |
/* |
| ... | ... | |
| 182 | 193 |
ret = bdrv_pread(bs->file, |
| 183 | 194 |
s->cow_sectors_offset + sector_num * 512, |
| 184 | 195 |
buf, n * 512); |
| 185 |
if (ret != n * 512) |
|
| 186 |
return -1; |
|
| 196 |
if (ret < 0) {
|
|
| 197 |
return ret; |
|
| 198 |
} |
|
| 187 | 199 |
} else {
|
| 188 | 200 |
if (bs->backing_hd) {
|
| 189 | 201 |
/* read from the base image */ |
| 190 | 202 |
ret = bdrv_read(bs->backing_hd, sector_num, buf, n); |
| 191 |
if (ret < 0) |
|
| 192 |
return -1; |
|
| 203 |
if (ret < 0) {
|
|
| 204 |
return ret; |
|
| 205 |
} |
|
| 193 | 206 |
} else {
|
| 194 |
memset(buf, 0, n * 512); |
|
| 195 |
} |
|
| 207 |
memset(buf, 0, n * 512);
|
|
| 208 |
}
|
|
| 196 | 209 |
} |
| 197 | 210 |
nb_sectors -= n; |
| 198 | 211 |
sector_num += n; |
| ... | ... | |
| 220 | 233 |
|
| 221 | 234 |
ret = bdrv_pwrite(bs->file, s->cow_sectors_offset + sector_num * 512, |
| 222 | 235 |
buf, nb_sectors * 512); |
| 223 |
if (ret != nb_sectors * 512) |
|
| 224 |
return -1; |
|
| 236 |
if (ret < 0) {
|
|
| 237 |
return ret; |
|
| 238 |
} |
|
| 225 | 239 |
|
| 226 | 240 |
return cow_update_bitmap(bs, sector_num, nb_sectors); |
| 227 | 241 |
} |
| ... | ... | |
| 288 | 302 |
cow_header.sectorsize = cpu_to_be32(512); |
| 289 | 303 |
cow_header.size = cpu_to_be64(image_sectors * 512); |
| 290 | 304 |
ret = bdrv_pwrite(cow_bs, 0, &cow_header, sizeof(cow_header)); |
| 291 |
if (ret != sizeof(cow_header)) {
|
|
| 305 |
if (ret < 0) {
|
|
| 292 | 306 |
goto exit; |
| 293 | 307 |
} |
| 294 | 308 |
|
| 295 | 309 |
/* resize to include at least all the bitmap */ |
| 296 | 310 |
ret = bdrv_truncate(cow_bs, |
| 297 | 311 |
sizeof(cow_header) + ((image_sectors + 7) >> 3)); |
| 298 |
if (ret) {
|
|
| 312 |
if (ret < 0) {
|
|
| 299 | 313 |
goto exit; |
| 300 | 314 |
} |
| 301 | 315 |
|
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