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1.1 root 1: /*
2: * Block driver for the QCOW version 2 format
3: *
4: * Copyright (c) 2004-2006 Fabrice Bellard
5: *
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: */
24:
25: #include "qemu-common.h"
26: #include "block_int.h"
27: #include "block/qcow2.h"
28:
29: static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size);
1.1.1.4 root 30: static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
1.1 root 31: int64_t offset, int64_t length,
32: int addend);
33:
34:
35: /*********************************************************/
36: /* refcount handling */
37:
38: int qcow2_refcount_init(BlockDriverState *bs)
39: {
40: BDRVQcowState *s = bs->opaque;
41: int ret, refcount_table_size2, i;
42:
43: refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
1.1.1.9 root 44: s->refcount_table = g_malloc(refcount_table_size2);
1.1 root 45: if (s->refcount_table_size > 0) {
1.1.1.6 root 46: BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_LOAD);
47: ret = bdrv_pread(bs->file, s->refcount_table_offset,
1.1 root 48: s->refcount_table, refcount_table_size2);
49: if (ret != refcount_table_size2)
50: goto fail;
51: for(i = 0; i < s->refcount_table_size; i++)
52: be64_to_cpus(&s->refcount_table[i]);
53: }
54: return 0;
55: fail:
56: return -ENOMEM;
57: }
58:
59: void qcow2_refcount_close(BlockDriverState *bs)
60: {
61: BDRVQcowState *s = bs->opaque;
1.1.1.9 root 62: g_free(s->refcount_table);
1.1 root 63: }
64:
65:
66: static int load_refcount_block(BlockDriverState *bs,
1.1.1.7 root 67: int64_t refcount_block_offset,
68: void **refcount_block)
1.1 root 69: {
70: BDRVQcowState *s = bs->opaque;
71: int ret;
72:
1.1.1.6 root 73: BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_LOAD);
1.1.1.7 root 74: ret = qcow2_cache_get(bs, s->refcount_block_cache, refcount_block_offset,
75: refcount_block);
1.1.1.6 root 76:
1.1.1.7 root 77: return ret;
1.1 root 78: }
79:
1.1.1.6 root 80: /*
81: * Returns the refcount of the cluster given by its index. Any non-negative
82: * return value is the refcount of the cluster, negative values are -errno
83: * and indicate an error.
84: */
1.1 root 85: static int get_refcount(BlockDriverState *bs, int64_t cluster_index)
86: {
87: BDRVQcowState *s = bs->opaque;
88: int refcount_table_index, block_index;
89: int64_t refcount_block_offset;
1.1.1.6 root 90: int ret;
1.1.1.7 root 91: uint16_t *refcount_block;
92: uint16_t refcount;
1.1 root 93:
94: refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
95: if (refcount_table_index >= s->refcount_table_size)
96: return 0;
97: refcount_block_offset = s->refcount_table[refcount_table_index];
98: if (!refcount_block_offset)
99: return 0;
1.1.1.7 root 100:
101: ret = qcow2_cache_get(bs, s->refcount_block_cache, refcount_block_offset,
102: (void**) &refcount_block);
103: if (ret < 0) {
104: return ret;
1.1 root 105: }
1.1.1.7 root 106:
1.1 root 107: block_index = cluster_index &
108: ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
1.1.1.7 root 109: refcount = be16_to_cpu(refcount_block[block_index]);
110:
111: ret = qcow2_cache_put(bs, s->refcount_block_cache,
112: (void**) &refcount_block);
113: if (ret < 0) {
114: return ret;
115: }
116:
117: return refcount;
1.1 root 118: }
119:
1.1.1.4 root 120: /*
121: * Rounds the refcount table size up to avoid growing the table for each single
122: * refcount block that is allocated.
123: */
124: static unsigned int next_refcount_table_size(BDRVQcowState *s,
125: unsigned int min_size)
126: {
127: unsigned int min_clusters = (min_size >> (s->cluster_bits - 3)) + 1;
128: unsigned int refcount_table_clusters =
129: MAX(1, s->refcount_table_size >> (s->cluster_bits - 3));
130:
131: while (min_clusters > refcount_table_clusters) {
132: refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2;
133: }
134:
135: return refcount_table_clusters << (s->cluster_bits - 3);
136: }
137:
138:
139: /* Checks if two offsets are described by the same refcount block */
140: static int in_same_refcount_block(BDRVQcowState *s, uint64_t offset_a,
141: uint64_t offset_b)
142: {
143: uint64_t block_a = offset_a >> (2 * s->cluster_bits - REFCOUNT_SHIFT);
144: uint64_t block_b = offset_b >> (2 * s->cluster_bits - REFCOUNT_SHIFT);
145:
146: return (block_a == block_b);
147: }
148:
149: /*
150: * Loads a refcount block. If it doesn't exist yet, it is allocated first
151: * (including growing the refcount table if needed).
152: *
1.1.1.7 root 153: * Returns 0 on success or -errno in error case
1.1.1.4 root 154: */
1.1.1.7 root 155: static int alloc_refcount_block(BlockDriverState *bs,
156: int64_t cluster_index, uint16_t **refcount_block)
1.1 root 157: {
158: BDRVQcowState *s = bs->opaque;
1.1.1.4 root 159: unsigned int refcount_table_index;
160: int ret;
1.1 root 161:
1.1.1.6 root 162: BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC);
163:
1.1.1.4 root 164: /* Find the refcount block for the given cluster */
165: refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
166:
167: if (refcount_table_index < s->refcount_table_size) {
168:
169: uint64_t refcount_block_offset =
1.1.1.10! root 170: s->refcount_table[refcount_table_index] & REFT_OFFSET_MASK;
1.1.1.4 root 171:
172: /* If it's already there, we're done */
173: if (refcount_block_offset) {
1.1.1.7 root 174: return load_refcount_block(bs, refcount_block_offset,
175: (void**) refcount_block);
1.1.1.4 root 176: }
177: }
178:
179: /*
180: * If we came here, we need to allocate something. Something is at least
181: * a cluster for the new refcount block. It may also include a new refcount
182: * table if the old refcount table is too small.
183: *
184: * Note that allocating clusters here needs some special care:
185: *
186: * - We can't use the normal qcow2_alloc_clusters(), it would try to
187: * increase the refcount and very likely we would end up with an endless
188: * recursion. Instead we must place the refcount blocks in a way that
189: * they can describe them themselves.
190: *
191: * - We need to consider that at this point we are inside update_refcounts
192: * and doing the initial refcount increase. This means that some clusters
193: * have already been allocated by the caller, but their refcount isn't
194: * accurate yet. free_cluster_index tells us where this allocation ends
195: * as long as we don't overwrite it by freeing clusters.
196: *
197: * - alloc_clusters_noref and qcow2_free_clusters may load a different
198: * refcount block into the cache
199: */
200:
1.1.1.7 root 201: *refcount_block = NULL;
202:
203: /* We write to the refcount table, so we might depend on L2 tables */
204: qcow2_cache_flush(bs, s->l2_table_cache);
1.1.1.4 root 205:
206: /* Allocate the refcount block itself and mark it as used */
1.1.1.6 root 207: int64_t new_block = alloc_clusters_noref(bs, s->cluster_size);
208: if (new_block < 0) {
209: return new_block;
210: }
1.1.1.4 root 211:
212: #ifdef DEBUG_ALLOC2
213: fprintf(stderr, "qcow2: Allocate refcount block %d for %" PRIx64
214: " at %" PRIx64 "\n",
215: refcount_table_index, cluster_index << s->cluster_bits, new_block);
216: #endif
217:
218: if (in_same_refcount_block(s, new_block, cluster_index << s->cluster_bits)) {
1.1.1.5 root 219: /* Zero the new refcount block before updating it */
1.1.1.7 root 220: ret = qcow2_cache_get_empty(bs, s->refcount_block_cache, new_block,
221: (void**) refcount_block);
222: if (ret < 0) {
223: goto fail_block;
224: }
225:
226: memset(*refcount_block, 0, s->cluster_size);
1.1.1.5 root 227:
1.1.1.4 root 228: /* The block describes itself, need to update the cache */
229: int block_index = (new_block >> s->cluster_bits) &
230: ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
1.1.1.7 root 231: (*refcount_block)[block_index] = cpu_to_be16(1);
1.1.1.4 root 232: } else {
233: /* Described somewhere else. This can recurse at most twice before we
234: * arrive at a block that describes itself. */
235: ret = update_refcount(bs, new_block, s->cluster_size, 1);
236: if (ret < 0) {
237: goto fail_block;
238: }
1.1.1.5 root 239:
1.1.1.7 root 240: bdrv_flush(bs->file);
241:
1.1.1.5 root 242: /* Initialize the new refcount block only after updating its refcount,
243: * update_refcount uses the refcount cache itself */
1.1.1.7 root 244: ret = qcow2_cache_get_empty(bs, s->refcount_block_cache, new_block,
245: (void**) refcount_block);
246: if (ret < 0) {
247: goto fail_block;
248: }
249:
250: memset(*refcount_block, 0, s->cluster_size);
1.1.1.4 root 251: }
252:
253: /* Now the new refcount block needs to be written to disk */
1.1.1.6 root 254: BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE);
1.1.1.7 root 255: qcow2_cache_entry_mark_dirty(s->refcount_block_cache, *refcount_block);
256: ret = qcow2_cache_flush(bs, s->refcount_block_cache);
1.1.1.4 root 257: if (ret < 0) {
258: goto fail_block;
259: }
260:
261: /* If the refcount table is big enough, just hook the block up there */
262: if (refcount_table_index < s->refcount_table_size) {
263: uint64_t data64 = cpu_to_be64(new_block);
1.1.1.6 root 264: BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_HOOKUP);
265: ret = bdrv_pwrite_sync(bs->file,
1.1.1.4 root 266: s->refcount_table_offset + refcount_table_index * sizeof(uint64_t),
267: &data64, sizeof(data64));
268: if (ret < 0) {
269: goto fail_block;
1.1 root 270: }
1.1.1.4 root 271:
272: s->refcount_table[refcount_table_index] = new_block;
1.1.1.7 root 273: return 0;
274: }
275:
276: ret = qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block);
277: if (ret < 0) {
278: goto fail_block;
1.1 root 279: }
1.1.1.4 root 280:
281: /*
282: * If we come here, we need to grow the refcount table. Again, a new
283: * refcount table needs some space and we can't simply allocate to avoid
284: * endless recursion.
285: *
286: * Therefore let's grab new refcount blocks at the end of the image, which
287: * will describe themselves and the new refcount table. This way we can
288: * reference them only in the new table and do the switch to the new
289: * refcount table at once without producing an inconsistent state in
290: * between.
291: */
1.1.1.6 root 292: BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_GROW);
293:
1.1.1.4 root 294: /* Calculate the number of refcount blocks needed so far */
295: uint64_t refcount_block_clusters = 1 << (s->cluster_bits - REFCOUNT_SHIFT);
296: uint64_t blocks_used = (s->free_cluster_index +
297: refcount_block_clusters - 1) / refcount_block_clusters;
298:
299: /* And now we need at least one block more for the new metadata */
300: uint64_t table_size = next_refcount_table_size(s, blocks_used + 1);
301: uint64_t last_table_size;
302: uint64_t blocks_clusters;
303: do {
304: uint64_t table_clusters = size_to_clusters(s, table_size);
305: blocks_clusters = 1 +
306: ((table_clusters + refcount_block_clusters - 1)
307: / refcount_block_clusters);
308: uint64_t meta_clusters = table_clusters + blocks_clusters;
309:
310: last_table_size = table_size;
311: table_size = next_refcount_table_size(s, blocks_used +
312: ((meta_clusters + refcount_block_clusters - 1)
313: / refcount_block_clusters));
314:
315: } while (last_table_size != table_size);
316:
1.1 root 317: #ifdef DEBUG_ALLOC2
1.1.1.4 root 318: fprintf(stderr, "qcow2: Grow refcount table %" PRId32 " => %" PRId64 "\n",
319: s->refcount_table_size, table_size);
1.1 root 320: #endif
1.1.1.4 root 321:
322: /* Create the new refcount table and blocks */
323: uint64_t meta_offset = (blocks_used * refcount_block_clusters) *
324: s->cluster_size;
325: uint64_t table_offset = meta_offset + blocks_clusters * s->cluster_size;
1.1.1.9 root 326: uint16_t *new_blocks = g_malloc0(blocks_clusters * s->cluster_size);
327: uint64_t *new_table = g_malloc0(table_size * sizeof(uint64_t));
1.1.1.4 root 328:
329: assert(meta_offset >= (s->free_cluster_index * s->cluster_size));
330:
331: /* Fill the new refcount table */
1.1 root 332: memcpy(new_table, s->refcount_table,
1.1.1.4 root 333: s->refcount_table_size * sizeof(uint64_t));
334: new_table[refcount_table_index] = new_block;
335:
336: int i;
337: for (i = 0; i < blocks_clusters; i++) {
338: new_table[blocks_used + i] = meta_offset + (i * s->cluster_size);
339: }
340:
341: /* Fill the refcount blocks */
342: uint64_t table_clusters = size_to_clusters(s, table_size * sizeof(uint64_t));
343: int block = 0;
344: for (i = 0; i < table_clusters + blocks_clusters; i++) {
345: new_blocks[block++] = cpu_to_be16(1);
346: }
347:
348: /* Write refcount blocks to disk */
1.1.1.6 root 349: BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS);
350: ret = bdrv_pwrite_sync(bs->file, meta_offset, new_blocks,
1.1.1.4 root 351: blocks_clusters * s->cluster_size);
1.1.1.9 root 352: g_free(new_blocks);
1.1.1.4 root 353: if (ret < 0) {
354: goto fail_table;
355: }
356:
357: /* Write refcount table to disk */
358: for(i = 0; i < table_size; i++) {
1.1 root 359: cpu_to_be64s(&new_table[i]);
1.1.1.4 root 360: }
361:
1.1.1.6 root 362: BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE);
363: ret = bdrv_pwrite_sync(bs->file, table_offset, new_table,
1.1.1.4 root 364: table_size * sizeof(uint64_t));
365: if (ret < 0) {
366: goto fail_table;
367: }
368:
369: for(i = 0; i < table_size; i++) {
1.1.1.10! root 370: be64_to_cpus(&new_table[i]);
1.1.1.4 root 371: }
1.1 root 372:
1.1.1.4 root 373: /* Hook up the new refcount table in the qcow2 header */
374: uint8_t data[12];
1.1 root 375: cpu_to_be64w((uint64_t*)data, table_offset);
1.1.1.4 root 376: cpu_to_be32w((uint32_t*)(data + 8), table_clusters);
1.1.1.6 root 377: BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE);
378: ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, refcount_table_offset),
1.1.1.4 root 379: data, sizeof(data));
380: if (ret < 0) {
381: goto fail_table;
1.1.1.3 root 382: }
383:
1.1.1.4 root 384: /* And switch it in memory */
385: uint64_t old_table_offset = s->refcount_table_offset;
386: uint64_t old_table_size = s->refcount_table_size;
387:
1.1.1.9 root 388: g_free(s->refcount_table);
1.1 root 389: s->refcount_table = new_table;
1.1.1.4 root 390: s->refcount_table_size = table_size;
1.1 root 391: s->refcount_table_offset = table_offset;
392:
1.1.1.4 root 393: /* Free old table. Remember, we must not change free_cluster_index */
394: uint64_t old_free_cluster_index = s->free_cluster_index;
1.1 root 395: qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t));
1.1.1.4 root 396: s->free_cluster_index = old_free_cluster_index;
1.1 root 397:
1.1.1.7 root 398: ret = load_refcount_block(bs, new_block, (void**) refcount_block);
1.1.1.4 root 399: if (ret < 0) {
1.1.1.7 root 400: return ret;
1.1 root 401: }
402:
1.1.1.10! root 403: return 0;
1.1 root 404:
1.1.1.4 root 405: fail_table:
1.1.1.9 root 406: g_free(new_table);
1.1.1.4 root 407: fail_block:
1.1.1.7 root 408: if (*refcount_block != NULL) {
409: qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block);
1.1.1.5 root 410: }
1.1.1.7 root 411: return ret;
1.1 root 412: }
413:
414: /* XXX: cache several refcount block clusters ? */
1.1.1.3 root 415: static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
416: int64_t offset, int64_t length, int addend)
1.1 root 417: {
418: BDRVQcowState *s = bs->opaque;
419: int64_t start, last, cluster_offset;
1.1.1.7 root 420: uint16_t *refcount_block = NULL;
421: int64_t old_table_index = -1;
1.1.1.3 root 422: int ret;
1.1 root 423:
424: #ifdef DEBUG_ALLOC2
1.1.1.9 root 425: fprintf(stderr, "update_refcount: offset=%" PRId64 " size=%" PRId64 " addend=%d\n",
1.1 root 426: offset, length, addend);
427: #endif
1.1.1.3 root 428: if (length < 0) {
1.1 root 429: return -EINVAL;
1.1.1.3 root 430: } else if (length == 0) {
431: return 0;
432: }
433:
1.1.1.7 root 434: if (addend < 0) {
435: qcow2_cache_set_dependency(bs, s->refcount_block_cache,
436: s->l2_table_cache);
437: }
438:
1.1 root 439: start = offset & ~(s->cluster_size - 1);
440: last = (offset + length - 1) & ~(s->cluster_size - 1);
441: for(cluster_offset = start; cluster_offset <= last;
442: cluster_offset += s->cluster_size)
443: {
444: int block_index, refcount;
445: int64_t cluster_index = cluster_offset >> s->cluster_bits;
1.1.1.7 root 446: int64_t table_index =
447: cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
1.1 root 448:
1.1.1.7 root 449: /* Load the refcount block and allocate it if needed */
450: if (table_index != old_table_index) {
451: if (refcount_block) {
452: ret = qcow2_cache_put(bs, s->refcount_block_cache,
453: (void**) &refcount_block);
454: if (ret < 0) {
455: goto fail;
456: }
457: }
1.1 root 458:
1.1.1.7 root 459: ret = alloc_refcount_block(bs, cluster_index, &refcount_block);
1.1.1.6 root 460: if (ret < 0) {
1.1.1.7 root 461: goto fail;
1.1 root 462: }
463: }
1.1.1.7 root 464: old_table_index = table_index;
1.1 root 465:
1.1.1.7 root 466: qcow2_cache_entry_mark_dirty(s->refcount_block_cache, refcount_block);
1.1 root 467:
468: /* we can update the count and save it */
469: block_index = cluster_index &
470: ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
471:
1.1.1.7 root 472: refcount = be16_to_cpu(refcount_block[block_index]);
1.1 root 473: refcount += addend;
1.1.1.3 root 474: if (refcount < 0 || refcount > 0xffff) {
475: ret = -EINVAL;
476: goto fail;
477: }
1.1 root 478: if (refcount == 0 && cluster_index < s->free_cluster_index) {
479: s->free_cluster_index = cluster_index;
480: }
1.1.1.7 root 481: refcount_block[block_index] = cpu_to_be16(refcount);
1.1 root 482: }
483:
1.1.1.3 root 484: ret = 0;
485: fail:
1.1 root 486: /* Write last changed block to disk */
1.1.1.7 root 487: if (refcount_block) {
1.1.1.6 root 488: int wret;
1.1.1.7 root 489: wret = qcow2_cache_put(bs, s->refcount_block_cache,
490: (void**) &refcount_block);
1.1.1.6 root 491: if (wret < 0) {
492: return ret < 0 ? ret : wret;
1.1 root 493: }
494: }
495:
1.1.1.3 root 496: /*
497: * Try do undo any updates if an error is returned (This may succeed in
498: * some cases like ENOSPC for allocating a new refcount block)
499: */
500: if (ret < 0) {
501: int dummy;
502: dummy = update_refcount(bs, offset, cluster_offset - offset, -addend);
1.1.1.7 root 503: (void)dummy;
1.1.1.3 root 504: }
505:
506: return ret;
1.1 root 507: }
508:
1.1.1.6 root 509: /*
510: * Increases or decreases the refcount of a given cluster by one.
511: * addend must be 1 or -1.
512: *
513: * If the return value is non-negative, it is the new refcount of the cluster.
514: * If it is negative, it is -errno and indicates an error.
515: */
1.1 root 516: static int update_cluster_refcount(BlockDriverState *bs,
517: int64_t cluster_index,
518: int addend)
519: {
520: BDRVQcowState *s = bs->opaque;
521: int ret;
522:
523: ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend);
524: if (ret < 0) {
525: return ret;
526: }
527:
1.1.1.7 root 528: bdrv_flush(bs->file);
529:
1.1 root 530: return get_refcount(bs, cluster_index);
531: }
532:
533:
534:
535: /*********************************************************/
536: /* cluster allocation functions */
537:
538:
539:
540: /* return < 0 if error */
541: static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
542: {
543: BDRVQcowState *s = bs->opaque;
1.1.1.6 root 544: int i, nb_clusters, refcount;
1.1 root 545:
546: nb_clusters = size_to_clusters(s, size);
547: retry:
548: for(i = 0; i < nb_clusters; i++) {
1.1.1.6 root 549: int64_t next_cluster_index = s->free_cluster_index++;
550: refcount = get_refcount(bs, next_cluster_index);
551:
552: if (refcount < 0) {
553: return refcount;
554: } else if (refcount != 0) {
1.1 root 555: goto retry;
1.1.1.6 root 556: }
1.1 root 557: }
558: #ifdef DEBUG_ALLOC2
1.1.1.9 root 559: fprintf(stderr, "alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n",
1.1 root 560: size,
561: (s->free_cluster_index - nb_clusters) << s->cluster_bits);
562: #endif
563: return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
564: }
565:
566: int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size)
567: {
568: int64_t offset;
1.1.1.3 root 569: int ret;
1.1 root 570:
1.1.1.6 root 571: BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC);
1.1 root 572: offset = alloc_clusters_noref(bs, size);
1.1.1.6 root 573: if (offset < 0) {
574: return offset;
575: }
576:
1.1.1.3 root 577: ret = update_refcount(bs, offset, size, 1);
578: if (ret < 0) {
579: return ret;
580: }
1.1.1.7 root 581:
1.1 root 582: return offset;
583: }
584:
1.1.1.10! root 585: int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
! 586: int nb_clusters)
! 587: {
! 588: BDRVQcowState *s = bs->opaque;
! 589: uint64_t cluster_index;
! 590: uint64_t old_free_cluster_index;
! 591: int i, refcount, ret;
! 592:
! 593: /* Check how many clusters there are free */
! 594: cluster_index = offset >> s->cluster_bits;
! 595: for(i = 0; i < nb_clusters; i++) {
! 596: refcount = get_refcount(bs, cluster_index++);
! 597:
! 598: if (refcount < 0) {
! 599: return refcount;
! 600: } else if (refcount != 0) {
! 601: break;
! 602: }
! 603: }
! 604:
! 605: /* And then allocate them */
! 606: old_free_cluster_index = s->free_cluster_index;
! 607: s->free_cluster_index = cluster_index + i;
! 608:
! 609: ret = update_refcount(bs, offset, i << s->cluster_bits, 1);
! 610: if (ret < 0) {
! 611: return ret;
! 612: }
! 613:
! 614: s->free_cluster_index = old_free_cluster_index;
! 615:
! 616: return i;
! 617: }
! 618:
1.1 root 619: /* only used to allocate compressed sectors. We try to allocate
620: contiguous sectors. size must be <= cluster_size */
621: int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
622: {
623: BDRVQcowState *s = bs->opaque;
624: int64_t offset, cluster_offset;
625: int free_in_cluster;
626:
1.1.1.6 root 627: BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC_BYTES);
1.1 root 628: assert(size > 0 && size <= s->cluster_size);
629: if (s->free_byte_offset == 0) {
630: s->free_byte_offset = qcow2_alloc_clusters(bs, s->cluster_size);
1.1.1.3 root 631: if (s->free_byte_offset < 0) {
632: return s->free_byte_offset;
633: }
1.1 root 634: }
635: redo:
636: free_in_cluster = s->cluster_size -
637: (s->free_byte_offset & (s->cluster_size - 1));
638: if (size <= free_in_cluster) {
639: /* enough space in current cluster */
640: offset = s->free_byte_offset;
641: s->free_byte_offset += size;
642: free_in_cluster -= size;
643: if (free_in_cluster == 0)
644: s->free_byte_offset = 0;
645: if ((offset & (s->cluster_size - 1)) != 0)
646: update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
647: } else {
648: offset = qcow2_alloc_clusters(bs, s->cluster_size);
1.1.1.3 root 649: if (offset < 0) {
650: return offset;
651: }
1.1 root 652: cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
653: if ((cluster_offset + s->cluster_size) == offset) {
654: /* we are lucky: contiguous data */
655: offset = s->free_byte_offset;
656: update_cluster_refcount(bs, offset >> s->cluster_bits, 1);
657: s->free_byte_offset += size;
658: } else {
659: s->free_byte_offset = offset;
660: goto redo;
661: }
662: }
1.1.1.7 root 663:
664: bdrv_flush(bs->file);
1.1 root 665: return offset;
666: }
667:
668: void qcow2_free_clusters(BlockDriverState *bs,
669: int64_t offset, int64_t size)
670: {
1.1.1.3 root 671: int ret;
672:
1.1.1.6 root 673: BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_FREE);
1.1.1.3 root 674: ret = update_refcount(bs, offset, size, -1);
675: if (ret < 0) {
676: fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
1.1.1.5 root 677: /* TODO Remember the clusters to free them later and avoid leaking */
1.1.1.3 root 678: }
1.1 root 679: }
680:
681: /*
1.1.1.10! root 682: * Free a cluster using its L2 entry (handles clusters of all types, e.g.
! 683: * normal cluster, compressed cluster, etc.)
1.1 root 684: */
685: void qcow2_free_any_clusters(BlockDriverState *bs,
1.1.1.10! root 686: uint64_t l2_entry, int nb_clusters)
1.1 root 687: {
688: BDRVQcowState *s = bs->opaque;
689:
1.1.1.10! root 690: switch (qcow2_get_cluster_type(l2_entry)) {
! 691: case QCOW2_CLUSTER_COMPRESSED:
! 692: {
! 693: int nb_csectors;
! 694: nb_csectors = ((l2_entry >> s->csize_shift) &
! 695: s->csize_mask) + 1;
! 696: qcow2_free_clusters(bs,
! 697: (l2_entry & s->cluster_offset_mask) & ~511,
! 698: nb_csectors * 512);
! 699: }
! 700: break;
! 701: case QCOW2_CLUSTER_NORMAL:
! 702: qcow2_free_clusters(bs, l2_entry & L2E_OFFSET_MASK,
! 703: nb_clusters << s->cluster_bits);
! 704: break;
! 705: case QCOW2_CLUSTER_UNALLOCATED:
! 706: case QCOW2_CLUSTER_ZERO:
! 707: break;
! 708: default:
! 709: abort();
1.1 root 710: }
711: }
712:
713:
714:
715: /*********************************************************/
716: /* snapshots and image creation */
717:
718:
719:
720: /* update the refcounts of snapshots and the copied flag */
721: int qcow2_update_snapshot_refcount(BlockDriverState *bs,
722: int64_t l1_table_offset, int l1_size, int addend)
723: {
724: BDRVQcowState *s = bs->opaque;
725: uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated;
726: int64_t old_offset, old_l2_offset;
1.1.1.8 root 727: int i, j, l1_modified = 0, nb_csectors, refcount;
1.1.1.7 root 728: int ret;
1.1.1.8 root 729: bool old_l2_writethrough, old_refcount_writethrough;
730:
731: /* Switch caches to writeback mode during update */
732: old_l2_writethrough =
733: qcow2_cache_set_writethrough(bs, s->l2_table_cache, false);
734: old_refcount_writethrough =
735: qcow2_cache_set_writethrough(bs, s->refcount_block_cache, false);
1.1 root 736:
737: l2_table = NULL;
738: l1_table = NULL;
739: l1_size2 = l1_size * sizeof(uint64_t);
1.1.1.10! root 740:
! 741: /* WARNING: qcow2_snapshot_goto relies on this function not using the
! 742: * l1_table_offset when it is the current s->l1_table_offset! Be careful
! 743: * when changing this! */
1.1 root 744: if (l1_table_offset != s->l1_table_offset) {
1.1.1.2 root 745: if (l1_size2 != 0) {
1.1.1.9 root 746: l1_table = g_malloc0(align_offset(l1_size2, 512));
1.1.1.2 root 747: } else {
748: l1_table = NULL;
749: }
1.1 root 750: l1_allocated = 1;
1.1.1.6 root 751: if (bdrv_pread(bs->file, l1_table_offset,
1.1 root 752: l1_table, l1_size2) != l1_size2)
1.1.1.8 root 753: {
754: ret = -EIO;
1.1 root 755: goto fail;
1.1.1.8 root 756: }
757:
1.1 root 758: for(i = 0;i < l1_size; i++)
759: be64_to_cpus(&l1_table[i]);
760: } else {
761: assert(l1_size == s->l1_size);
762: l1_table = s->l1_table;
763: l1_allocated = 0;
764: }
765:
766: for(i = 0; i < l1_size; i++) {
767: l2_offset = l1_table[i];
768: if (l2_offset) {
769: old_l2_offset = l2_offset;
1.1.1.10! root 770: l2_offset &= L1E_OFFSET_MASK;
1.1.1.7 root 771:
772: ret = qcow2_cache_get(bs, s->l2_table_cache, l2_offset,
773: (void**) &l2_table);
774: if (ret < 0) {
1.1 root 775: goto fail;
1.1.1.7 root 776: }
777:
1.1 root 778: for(j = 0; j < s->l2_size; j++) {
779: offset = be64_to_cpu(l2_table[j]);
780: if (offset != 0) {
781: old_offset = offset;
782: offset &= ~QCOW_OFLAG_COPIED;
783: if (offset & QCOW_OFLAG_COMPRESSED) {
784: nb_csectors = ((offset >> s->csize_shift) &
785: s->csize_mask) + 1;
1.1.1.3 root 786: if (addend != 0) {
787: int ret;
788: ret = update_refcount(bs,
789: (offset & s->cluster_offset_mask) & ~511,
790: nb_csectors * 512, addend);
791: if (ret < 0) {
792: goto fail;
793: }
1.1.1.7 root 794:
795: /* TODO Flushing once for the whole function should
796: * be enough */
797: bdrv_flush(bs->file);
1.1.1.3 root 798: }
1.1 root 799: /* compressed clusters are never modified */
800: refcount = 2;
801: } else {
1.1.1.10! root 802: uint64_t cluster_index = (offset & L2E_OFFSET_MASK) >> s->cluster_bits;
1.1 root 803: if (addend != 0) {
1.1.1.10! root 804: refcount = update_cluster_refcount(bs, cluster_index, addend);
1.1 root 805: } else {
1.1.1.10! root 806: refcount = get_refcount(bs, cluster_index);
1.1 root 807: }
1.1.1.6 root 808:
809: if (refcount < 0) {
1.1.1.8 root 810: ret = -EIO;
1.1.1.6 root 811: goto fail;
812: }
1.1 root 813: }
814:
815: if (refcount == 1) {
816: offset |= QCOW_OFLAG_COPIED;
817: }
818: if (offset != old_offset) {
1.1.1.7 root 819: if (addend > 0) {
820: qcow2_cache_set_dependency(bs, s->l2_table_cache,
821: s->refcount_block_cache);
822: }
1.1 root 823: l2_table[j] = cpu_to_be64(offset);
1.1.1.7 root 824: qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
1.1 root 825: }
826: }
827: }
1.1.1.7 root 828:
829: ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
830: if (ret < 0) {
831: goto fail;
1.1 root 832: }
833:
1.1.1.7 root 834:
1.1 root 835: if (addend != 0) {
836: refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend);
837: } else {
838: refcount = get_refcount(bs, l2_offset >> s->cluster_bits);
839: }
1.1.1.6 root 840: if (refcount < 0) {
1.1.1.8 root 841: ret = -EIO;
1.1.1.6 root 842: goto fail;
843: } else if (refcount == 1) {
1.1 root 844: l2_offset |= QCOW_OFLAG_COPIED;
845: }
846: if (l2_offset != old_l2_offset) {
847: l1_table[i] = l2_offset;
848: l1_modified = 1;
849: }
850: }
851: }
1.1.1.8 root 852:
853: ret = 0;
854: fail:
855: if (l2_table) {
856: qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
857: }
858:
859: /* Enable writethrough cache mode again */
860: qcow2_cache_set_writethrough(bs, s->l2_table_cache, old_l2_writethrough);
861: qcow2_cache_set_writethrough(bs, s->refcount_block_cache,
862: old_refcount_writethrough);
863:
1.1.1.10! root 864: /* Update L1 only if it isn't deleted anyway (addend = -1) */
! 865: if (addend >= 0 && l1_modified) {
1.1 root 866: for(i = 0; i < l1_size; i++)
867: cpu_to_be64s(&l1_table[i]);
1.1.1.6 root 868: if (bdrv_pwrite_sync(bs->file, l1_table_offset, l1_table,
1.1.1.5 root 869: l1_size2) < 0)
1.1 root 870: goto fail;
871: for(i = 0; i < l1_size; i++)
872: be64_to_cpus(&l1_table[i]);
873: }
874: if (l1_allocated)
1.1.1.9 root 875: g_free(l1_table);
1.1.1.8 root 876: return ret;
1.1 root 877: }
878:
879:
880:
881:
882: /*********************************************************/
883: /* refcount checking functions */
884:
885:
886:
887: /*
888: * Increases the refcount for a range of clusters in a given refcount table.
889: * This is used to construct a temporary refcount table out of L1 and L2 tables
890: * which can be compared the the refcount table saved in the image.
891: *
1.1.1.6 root 892: * Modifies the number of errors in res.
1.1 root 893: */
1.1.1.6 root 894: static void inc_refcounts(BlockDriverState *bs,
895: BdrvCheckResult *res,
1.1 root 896: uint16_t *refcount_table,
897: int refcount_table_size,
898: int64_t offset, int64_t size)
899: {
900: BDRVQcowState *s = bs->opaque;
901: int64_t start, last, cluster_offset;
902: int k;
903:
904: if (size <= 0)
1.1.1.6 root 905: return;
1.1 root 906:
907: start = offset & ~(s->cluster_size - 1);
908: last = (offset + size - 1) & ~(s->cluster_size - 1);
909: for(cluster_offset = start; cluster_offset <= last;
910: cluster_offset += s->cluster_size) {
911: k = cluster_offset >> s->cluster_bits;
1.1.1.6 root 912: if (k < 0) {
1.1 root 913: fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n",
914: cluster_offset);
1.1.1.6 root 915: res->corruptions++;
916: } else if (k >= refcount_table_size) {
917: fprintf(stderr, "Warning: cluster offset=0x%" PRIx64 " is after "
918: "the end of the image file, can't properly check refcounts.\n",
919: cluster_offset);
920: res->check_errors++;
1.1 root 921: } else {
922: if (++refcount_table[k] == 0) {
923: fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
924: "\n", cluster_offset);
1.1.1.6 root 925: res->corruptions++;
1.1 root 926: }
927: }
928: }
929: }
930:
931: /*
932: * Increases the refcount in the given refcount table for the all clusters
933: * referenced in the L2 table. While doing so, performs some checks on L2
934: * entries.
935: *
936: * Returns the number of errors found by the checks or -errno if an internal
937: * error occurred.
938: */
1.1.1.6 root 939: static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res,
1.1 root 940: uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
941: int check_copied)
942: {
943: BDRVQcowState *s = bs->opaque;
1.1.1.10! root 944: uint64_t *l2_table, l2_entry;
1.1 root 945: int i, l2_size, nb_csectors, refcount;
946:
947: /* Read L2 table from disk */
948: l2_size = s->l2_size * sizeof(uint64_t);
1.1.1.9 root 949: l2_table = g_malloc(l2_size);
1.1 root 950:
1.1.1.6 root 951: if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
1.1 root 952: goto fail;
953:
954: /* Do the actual checks */
955: for(i = 0; i < s->l2_size; i++) {
1.1.1.10! root 956: l2_entry = be64_to_cpu(l2_table[i]);
1.1 root 957:
1.1.1.10! root 958: switch (qcow2_get_cluster_type(l2_entry)) {
! 959: case QCOW2_CLUSTER_COMPRESSED:
! 960: /* Compressed clusters don't have QCOW_OFLAG_COPIED */
! 961: if (l2_entry & QCOW_OFLAG_COPIED) {
! 962: fprintf(stderr, "ERROR: cluster %" PRId64 ": "
! 963: "copied flag must never be set for compressed "
! 964: "clusters\n", l2_entry >> s->cluster_bits);
! 965: l2_entry &= ~QCOW_OFLAG_COPIED;
! 966: res->corruptions++;
! 967: }
! 968:
! 969: /* Mark cluster as used */
! 970: nb_csectors = ((l2_entry >> s->csize_shift) &
! 971: s->csize_mask) + 1;
! 972: l2_entry &= s->cluster_offset_mask;
! 973: inc_refcounts(bs, res, refcount_table, refcount_table_size,
! 974: l2_entry & ~511, nb_csectors * 512);
! 975: break;
! 976:
! 977: case QCOW2_CLUSTER_ZERO:
! 978: if ((l2_entry & L2E_OFFSET_MASK) == 0) {
! 979: break;
! 980: }
! 981: /* fall through */
1.1 root 982:
1.1.1.10! root 983: case QCOW2_CLUSTER_NORMAL:
! 984: {
! 985: /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
! 986: uint64_t offset = l2_entry & L2E_OFFSET_MASK;
! 987:
! 988: if (check_copied) {
! 989: refcount = get_refcount(bs, offset >> s->cluster_bits);
! 990: if (refcount < 0) {
! 991: fprintf(stderr, "Can't get refcount for offset %"
! 992: PRIx64 ": %s\n", l2_entry, strerror(-refcount));
! 993: goto fail;
! 994: }
! 995: if ((refcount == 1) != ((l2_entry & QCOW_OFLAG_COPIED) != 0)) {
! 996: fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
! 997: PRIx64 " refcount=%d\n", l2_entry, refcount);
1.1.1.6 root 998: res->corruptions++;
1.1 root 999: }
1000: }
1.1.1.10! root 1001:
! 1002: /* Mark cluster as used */
! 1003: inc_refcounts(bs, res, refcount_table,refcount_table_size,
! 1004: offset, s->cluster_size);
! 1005:
! 1006: /* Correct offsets are cluster aligned */
! 1007: if (offset & (s->cluster_size - 1)) {
! 1008: fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not "
! 1009: "properly aligned; L2 entry corrupted.\n", offset);
! 1010: res->corruptions++;
! 1011: }
! 1012: break;
! 1013: }
! 1014:
! 1015: case QCOW2_CLUSTER_UNALLOCATED:
! 1016: break;
! 1017:
! 1018: default:
! 1019: abort();
1.1 root 1020: }
1021: }
1022:
1.1.1.9 root 1023: g_free(l2_table);
1.1.1.6 root 1024: return 0;
1.1 root 1025:
1026: fail:
1.1.1.6 root 1027: fprintf(stderr, "ERROR: I/O error in check_refcounts_l2\n");
1.1.1.9 root 1028: g_free(l2_table);
1.1 root 1029: return -EIO;
1030: }
1031:
1032: /*
1033: * Increases the refcount for the L1 table, its L2 tables and all referenced
1034: * clusters in the given refcount table. While doing so, performs some checks
1035: * on L1 and L2 entries.
1036: *
1037: * Returns the number of errors found by the checks or -errno if an internal
1038: * error occurred.
1039: */
1040: static int check_refcounts_l1(BlockDriverState *bs,
1.1.1.6 root 1041: BdrvCheckResult *res,
1.1 root 1042: uint16_t *refcount_table,
1043: int refcount_table_size,
1044: int64_t l1_table_offset, int l1_size,
1045: int check_copied)
1046: {
1047: BDRVQcowState *s = bs->opaque;
1048: uint64_t *l1_table, l2_offset, l1_size2;
1049: int i, refcount, ret;
1050:
1051: l1_size2 = l1_size * sizeof(uint64_t);
1052:
1053: /* Mark L1 table as used */
1.1.1.6 root 1054: inc_refcounts(bs, res, refcount_table, refcount_table_size,
1055: l1_table_offset, l1_size2);
1.1 root 1056:
1057: /* Read L1 table entries from disk */
1.1.1.2 root 1058: if (l1_size2 == 0) {
1059: l1_table = NULL;
1060: } else {
1.1.1.9 root 1061: l1_table = g_malloc(l1_size2);
1.1.1.6 root 1062: if (bdrv_pread(bs->file, l1_table_offset,
1.1.1.2 root 1063: l1_table, l1_size2) != l1_size2)
1064: goto fail;
1065: for(i = 0;i < l1_size; i++)
1066: be64_to_cpus(&l1_table[i]);
1067: }
1.1 root 1068:
1069: /* Do the actual checks */
1070: for(i = 0; i < l1_size; i++) {
1071: l2_offset = l1_table[i];
1072: if (l2_offset) {
1073: /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
1074: if (check_copied) {
1075: refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED)
1076: >> s->cluster_bits);
1.1.1.6 root 1077: if (refcount < 0) {
1078: fprintf(stderr, "Can't get refcount for l2_offset %"
1079: PRIx64 ": %s\n", l2_offset, strerror(-refcount));
1080: goto fail;
1081: }
1.1 root 1082: if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) {
1083: fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
1084: " refcount=%d\n", l2_offset, refcount);
1.1.1.6 root 1085: res->corruptions++;
1.1 root 1086: }
1087: }
1088:
1089: /* Mark L2 table as used */
1.1.1.10! root 1090: l2_offset &= L1E_OFFSET_MASK;
1.1.1.6 root 1091: inc_refcounts(bs, res, refcount_table, refcount_table_size,
1092: l2_offset, s->cluster_size);
1.1 root 1093:
1094: /* L2 tables are cluster aligned */
1095: if (l2_offset & (s->cluster_size - 1)) {
1096: fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not "
1097: "cluster aligned; L1 entry corrupted\n", l2_offset);
1.1.1.6 root 1098: res->corruptions++;
1.1 root 1099: }
1100:
1101: /* Process and check L2 entries */
1.1.1.6 root 1102: ret = check_refcounts_l2(bs, res, refcount_table,
1103: refcount_table_size, l2_offset, check_copied);
1.1 root 1104: if (ret < 0) {
1105: goto fail;
1106: }
1107: }
1108: }
1.1.1.9 root 1109: g_free(l1_table);
1.1.1.6 root 1110: return 0;
1.1 root 1111:
1112: fail:
1113: fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
1.1.1.6 root 1114: res->check_errors++;
1.1.1.9 root 1115: g_free(l1_table);
1.1 root 1116: return -EIO;
1117: }
1118:
1119: /*
1120: * Checks an image for refcount consistency.
1121: *
1122: * Returns 0 if no errors are found, the number of errors in case the image is
1.1.1.8 root 1123: * detected as corrupted, and -errno when an internal error occurred.
1.1 root 1124: */
1.1.1.6 root 1125: int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res)
1.1 root 1126: {
1127: BDRVQcowState *s = bs->opaque;
1128: int64_t size;
1129: int nb_clusters, refcount1, refcount2, i;
1130: QCowSnapshot *sn;
1131: uint16_t *refcount_table;
1.1.1.6 root 1132: int ret;
1.1 root 1133:
1.1.1.6 root 1134: size = bdrv_getlength(bs->file);
1.1 root 1135: nb_clusters = size_to_clusters(s, size);
1.1.1.9 root 1136: refcount_table = g_malloc0(nb_clusters * sizeof(uint16_t));
1.1 root 1137:
1138: /* header */
1.1.1.6 root 1139: inc_refcounts(bs, res, refcount_table, nb_clusters,
1140: 0, s->cluster_size);
1.1 root 1141:
1142: /* current L1 table */
1.1.1.6 root 1143: ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters,
1.1 root 1144: s->l1_table_offset, s->l1_size, 1);
1145: if (ret < 0) {
1.1.1.8 root 1146: goto fail;
1.1 root 1147: }
1148:
1149: /* snapshots */
1150: for(i = 0; i < s->nb_snapshots; i++) {
1151: sn = s->snapshots + i;
1.1.1.6 root 1152: ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters,
1153: sn->l1_table_offset, sn->l1_size, 0);
1154: if (ret < 0) {
1.1.1.8 root 1155: goto fail;
1.1.1.6 root 1156: }
1.1 root 1157: }
1.1.1.6 root 1158: inc_refcounts(bs, res, refcount_table, nb_clusters,
1159: s->snapshots_offset, s->snapshots_size);
1.1 root 1160:
1161: /* refcount data */
1.1.1.6 root 1162: inc_refcounts(bs, res, refcount_table, nb_clusters,
1163: s->refcount_table_offset,
1164: s->refcount_table_size * sizeof(uint64_t));
1165:
1.1 root 1166: for(i = 0; i < s->refcount_table_size; i++) {
1.1.1.6 root 1167: uint64_t offset, cluster;
1.1 root 1168: offset = s->refcount_table[i];
1.1.1.6 root 1169: cluster = offset >> s->cluster_bits;
1170:
1171: /* Refcount blocks are cluster aligned */
1172: if (offset & (s->cluster_size - 1)) {
1173: fprintf(stderr, "ERROR refcount block %d is not "
1174: "cluster aligned; refcount table entry corrupted\n", i);
1175: res->corruptions++;
1176: continue;
1177: }
1178:
1179: if (cluster >= nb_clusters) {
1180: fprintf(stderr, "ERROR refcount block %d is outside image\n", i);
1181: res->corruptions++;
1182: continue;
1183: }
1184:
1.1 root 1185: if (offset != 0) {
1.1.1.6 root 1186: inc_refcounts(bs, res, refcount_table, nb_clusters,
1187: offset, s->cluster_size);
1188: if (refcount_table[cluster] != 1) {
1189: fprintf(stderr, "ERROR refcount block %d refcount=%d\n",
1190: i, refcount_table[cluster]);
1191: res->corruptions++;
1192: }
1.1 root 1193: }
1194: }
1195:
1196: /* compare ref counts */
1197: for(i = 0; i < nb_clusters; i++) {
1198: refcount1 = get_refcount(bs, i);
1.1.1.6 root 1199: if (refcount1 < 0) {
1200: fprintf(stderr, "Can't get refcount for cluster %d: %s\n",
1201: i, strerror(-refcount1));
1202: res->check_errors++;
1203: continue;
1204: }
1205:
1.1 root 1206: refcount2 = refcount_table[i];
1207: if (refcount1 != refcount2) {
1.1.1.6 root 1208: fprintf(stderr, "%s cluster %d refcount=%d reference=%d\n",
1209: refcount1 < refcount2 ? "ERROR" : "Leaked",
1.1 root 1210: i, refcount1, refcount2);
1.1.1.6 root 1211: if (refcount1 < refcount2) {
1212: res->corruptions++;
1213: } else {
1214: res->leaks++;
1215: }
1.1 root 1216: }
1217: }
1218:
1.1.1.8 root 1219: ret = 0;
1220:
1221: fail:
1.1.1.9 root 1222: g_free(refcount_table);
1.1 root 1223:
1.1.1.8 root 1224: return ret;
1.1 root 1225: }
1226:
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