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1.1 root 1: /*
2: * Block driver for the QCOW 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: #include "qemu-common.h"
25: #include "block_int.h"
26: #include "module.h"
27: #include <zlib.h>
28: #include "aes.h"
1.1.1.6 ! root 29: #include "migration.h"
1.1 root 30:
31: /**************************************************************/
32: /* QEMU COW block driver with compression and encryption support */
33:
34: #define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)
35: #define QCOW_VERSION 1
36:
37: #define QCOW_CRYPT_NONE 0
38: #define QCOW_CRYPT_AES 1
39:
40: #define QCOW_OFLAG_COMPRESSED (1LL << 63)
41:
42: typedef struct QCowHeader {
43: uint32_t magic;
44: uint32_t version;
45: uint64_t backing_file_offset;
46: uint32_t backing_file_size;
47: uint32_t mtime;
48: uint64_t size; /* in bytes */
49: uint8_t cluster_bits;
50: uint8_t l2_bits;
51: uint32_t crypt_method;
52: uint64_t l1_table_offset;
53: } QCowHeader;
54:
55: #define L2_CACHE_SIZE 16
56:
57: typedef struct BDRVQcowState {
58: int cluster_bits;
59: int cluster_size;
60: int cluster_sectors;
61: int l2_bits;
62: int l2_size;
63: int l1_size;
64: uint64_t cluster_offset_mask;
65: uint64_t l1_table_offset;
66: uint64_t *l1_table;
67: uint64_t *l2_cache;
68: uint64_t l2_cache_offsets[L2_CACHE_SIZE];
69: uint32_t l2_cache_counts[L2_CACHE_SIZE];
70: uint8_t *cluster_cache;
71: uint8_t *cluster_data;
72: uint64_t cluster_cache_offset;
73: uint32_t crypt_method; /* current crypt method, 0 if no key yet */
74: uint32_t crypt_method_header;
75: AES_KEY aes_encrypt_key;
76: AES_KEY aes_decrypt_key;
1.1.1.6 ! root 77: CoMutex lock;
! 78: Error *migration_blocker;
1.1 root 79: } BDRVQcowState;
80:
1.1.1.3 root 81: static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
1.1 root 82:
83: static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
84: {
85: const QCowHeader *cow_header = (const void *)buf;
86:
87: if (buf_size >= sizeof(QCowHeader) &&
88: be32_to_cpu(cow_header->magic) == QCOW_MAGIC &&
89: be32_to_cpu(cow_header->version) == QCOW_VERSION)
90: return 100;
91: else
92: return 0;
93: }
94:
1.1.1.3 root 95: static int qcow_open(BlockDriverState *bs, int flags)
1.1 root 96: {
97: BDRVQcowState *s = bs->opaque;
1.1.1.3 root 98: int len, i, shift;
1.1 root 99: QCowHeader header;
100:
1.1.1.3 root 101: if (bdrv_pread(bs->file, 0, &header, sizeof(header)) != sizeof(header))
1.1 root 102: goto fail;
103: be32_to_cpus(&header.magic);
104: be32_to_cpus(&header.version);
105: be64_to_cpus(&header.backing_file_offset);
106: be32_to_cpus(&header.backing_file_size);
107: be32_to_cpus(&header.mtime);
108: be64_to_cpus(&header.size);
109: be32_to_cpus(&header.crypt_method);
110: be64_to_cpus(&header.l1_table_offset);
111:
112: if (header.magic != QCOW_MAGIC || header.version != QCOW_VERSION)
113: goto fail;
114: if (header.size <= 1 || header.cluster_bits < 9)
115: goto fail;
116: if (header.crypt_method > QCOW_CRYPT_AES)
117: goto fail;
118: s->crypt_method_header = header.crypt_method;
119: if (s->crypt_method_header)
120: bs->encrypted = 1;
121: s->cluster_bits = header.cluster_bits;
122: s->cluster_size = 1 << s->cluster_bits;
123: s->cluster_sectors = 1 << (s->cluster_bits - 9);
124: s->l2_bits = header.l2_bits;
125: s->l2_size = 1 << s->l2_bits;
126: bs->total_sectors = header.size / 512;
127: s->cluster_offset_mask = (1LL << (63 - s->cluster_bits)) - 1;
128:
129: /* read the level 1 table */
130: shift = s->cluster_bits + s->l2_bits;
131: s->l1_size = (header.size + (1LL << shift) - 1) >> shift;
132:
133: s->l1_table_offset = header.l1_table_offset;
1.1.1.6 ! root 134: s->l1_table = g_malloc(s->l1_size * sizeof(uint64_t));
1.1 root 135: if (!s->l1_table)
136: goto fail;
1.1.1.3 root 137: if (bdrv_pread(bs->file, s->l1_table_offset, s->l1_table, s->l1_size * sizeof(uint64_t)) !=
1.1 root 138: s->l1_size * sizeof(uint64_t))
139: goto fail;
140: for(i = 0;i < s->l1_size; i++) {
141: be64_to_cpus(&s->l1_table[i]);
142: }
143: /* alloc L2 cache */
1.1.1.6 ! root 144: s->l2_cache = g_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
1.1 root 145: if (!s->l2_cache)
146: goto fail;
1.1.1.6 ! root 147: s->cluster_cache = g_malloc(s->cluster_size);
1.1 root 148: if (!s->cluster_cache)
149: goto fail;
1.1.1.6 ! root 150: s->cluster_data = g_malloc(s->cluster_size);
1.1 root 151: if (!s->cluster_data)
152: goto fail;
153: s->cluster_cache_offset = -1;
154:
155: /* read the backing file name */
156: if (header.backing_file_offset != 0) {
157: len = header.backing_file_size;
158: if (len > 1023)
159: len = 1023;
1.1.1.3 root 160: if (bdrv_pread(bs->file, header.backing_file_offset, bs->backing_file, len) != len)
1.1 root 161: goto fail;
162: bs->backing_file[len] = '\0';
163: }
1.1.1.6 ! root 164:
! 165: /* Disable migration when qcow images are used */
! 166: error_set(&s->migration_blocker,
! 167: QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
! 168: "qcow", bs->device_name, "live migration");
! 169: migrate_add_blocker(s->migration_blocker);
! 170:
! 171: qemu_co_mutex_init(&s->lock);
1.1 root 172: return 0;
173:
174: fail:
1.1.1.6 ! root 175: g_free(s->l1_table);
! 176: g_free(s->l2_cache);
! 177: g_free(s->cluster_cache);
! 178: g_free(s->cluster_data);
1.1 root 179: return -1;
180: }
181:
182: static int qcow_set_key(BlockDriverState *bs, const char *key)
183: {
184: BDRVQcowState *s = bs->opaque;
185: uint8_t keybuf[16];
186: int len, i;
187:
188: memset(keybuf, 0, 16);
189: len = strlen(key);
190: if (len > 16)
191: len = 16;
192: /* XXX: we could compress the chars to 7 bits to increase
193: entropy */
194: for(i = 0;i < len;i++) {
195: keybuf[i] = key[i];
196: }
197: s->crypt_method = s->crypt_method_header;
198:
199: if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0)
200: return -1;
201: if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0)
202: return -1;
203: return 0;
204: }
205:
206: /* The crypt function is compatible with the linux cryptoloop
207: algorithm for < 4 GB images. NOTE: out_buf == in_buf is
208: supported */
209: static void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
210: uint8_t *out_buf, const uint8_t *in_buf,
211: int nb_sectors, int enc,
212: const AES_KEY *key)
213: {
214: union {
215: uint64_t ll[2];
216: uint8_t b[16];
217: } ivec;
218: int i;
219:
220: for(i = 0; i < nb_sectors; i++) {
221: ivec.ll[0] = cpu_to_le64(sector_num);
222: ivec.ll[1] = 0;
223: AES_cbc_encrypt(in_buf, out_buf, 512, key,
224: ivec.b, enc);
225: sector_num++;
226: in_buf += 512;
227: out_buf += 512;
228: }
229: }
230:
231: /* 'allocate' is:
232: *
233: * 0 to not allocate.
234: *
235: * 1 to allocate a normal cluster (for sector indexes 'n_start' to
236: * 'n_end')
237: *
238: * 2 to allocate a compressed cluster of size
239: * 'compressed_size'. 'compressed_size' must be > 0 and <
240: * cluster_size
241: *
242: * return 0 if not allocated.
243: */
244: static uint64_t get_cluster_offset(BlockDriverState *bs,
245: uint64_t offset, int allocate,
246: int compressed_size,
247: int n_start, int n_end)
248: {
249: BDRVQcowState *s = bs->opaque;
250: int min_index, i, j, l1_index, l2_index;
251: uint64_t l2_offset, *l2_table, cluster_offset, tmp;
252: uint32_t min_count;
253: int new_l2_table;
254:
255: l1_index = offset >> (s->l2_bits + s->cluster_bits);
256: l2_offset = s->l1_table[l1_index];
257: new_l2_table = 0;
258: if (!l2_offset) {
259: if (!allocate)
260: return 0;
261: /* allocate a new l2 entry */
1.1.1.3 root 262: l2_offset = bdrv_getlength(bs->file);
1.1 root 263: /* round to cluster size */
264: l2_offset = (l2_offset + s->cluster_size - 1) & ~(s->cluster_size - 1);
265: /* update the L1 entry */
266: s->l1_table[l1_index] = l2_offset;
267: tmp = cpu_to_be64(l2_offset);
1.1.1.3 root 268: if (bdrv_pwrite_sync(bs->file,
1.1.1.2 root 269: s->l1_table_offset + l1_index * sizeof(tmp),
270: &tmp, sizeof(tmp)) < 0)
1.1 root 271: return 0;
272: new_l2_table = 1;
273: }
274: for(i = 0; i < L2_CACHE_SIZE; i++) {
275: if (l2_offset == s->l2_cache_offsets[i]) {
276: /* increment the hit count */
277: if (++s->l2_cache_counts[i] == 0xffffffff) {
278: for(j = 0; j < L2_CACHE_SIZE; j++) {
279: s->l2_cache_counts[j] >>= 1;
280: }
281: }
282: l2_table = s->l2_cache + (i << s->l2_bits);
283: goto found;
284: }
285: }
286: /* not found: load a new entry in the least used one */
287: min_index = 0;
288: min_count = 0xffffffff;
289: for(i = 0; i < L2_CACHE_SIZE; i++) {
290: if (s->l2_cache_counts[i] < min_count) {
291: min_count = s->l2_cache_counts[i];
292: min_index = i;
293: }
294: }
295: l2_table = s->l2_cache + (min_index << s->l2_bits);
296: if (new_l2_table) {
297: memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
1.1.1.3 root 298: if (bdrv_pwrite_sync(bs->file, l2_offset, l2_table,
1.1.1.2 root 299: s->l2_size * sizeof(uint64_t)) < 0)
1.1 root 300: return 0;
301: } else {
1.1.1.3 root 302: if (bdrv_pread(bs->file, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
1.1 root 303: s->l2_size * sizeof(uint64_t))
304: return 0;
305: }
306: s->l2_cache_offsets[min_index] = l2_offset;
307: s->l2_cache_counts[min_index] = 1;
308: found:
309: l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
310: cluster_offset = be64_to_cpu(l2_table[l2_index]);
311: if (!cluster_offset ||
312: ((cluster_offset & QCOW_OFLAG_COMPRESSED) && allocate == 1)) {
313: if (!allocate)
314: return 0;
315: /* allocate a new cluster */
316: if ((cluster_offset & QCOW_OFLAG_COMPRESSED) &&
317: (n_end - n_start) < s->cluster_sectors) {
318: /* if the cluster is already compressed, we must
319: decompress it in the case it is not completely
320: overwritten */
1.1.1.3 root 321: if (decompress_cluster(bs, cluster_offset) < 0)
1.1 root 322: return 0;
1.1.1.3 root 323: cluster_offset = bdrv_getlength(bs->file);
1.1 root 324: cluster_offset = (cluster_offset + s->cluster_size - 1) &
325: ~(s->cluster_size - 1);
326: /* write the cluster content */
1.1.1.3 root 327: if (bdrv_pwrite(bs->file, cluster_offset, s->cluster_cache, s->cluster_size) !=
1.1 root 328: s->cluster_size)
329: return -1;
330: } else {
1.1.1.3 root 331: cluster_offset = bdrv_getlength(bs->file);
1.1 root 332: if (allocate == 1) {
333: /* round to cluster size */
334: cluster_offset = (cluster_offset + s->cluster_size - 1) &
335: ~(s->cluster_size - 1);
1.1.1.3 root 336: bdrv_truncate(bs->file, cluster_offset + s->cluster_size);
1.1 root 337: /* if encrypted, we must initialize the cluster
338: content which won't be written */
339: if (s->crypt_method &&
340: (n_end - n_start) < s->cluster_sectors) {
341: uint64_t start_sect;
342: start_sect = (offset & ~(s->cluster_size - 1)) >> 9;
343: memset(s->cluster_data + 512, 0x00, 512);
344: for(i = 0; i < s->cluster_sectors; i++) {
345: if (i < n_start || i >= n_end) {
346: encrypt_sectors(s, start_sect + i,
347: s->cluster_data,
348: s->cluster_data + 512, 1, 1,
349: &s->aes_encrypt_key);
1.1.1.3 root 350: if (bdrv_pwrite(bs->file, cluster_offset + i * 512,
1.1 root 351: s->cluster_data, 512) != 512)
352: return -1;
353: }
354: }
355: }
356: } else if (allocate == 2) {
357: cluster_offset |= QCOW_OFLAG_COMPRESSED |
358: (uint64_t)compressed_size << (63 - s->cluster_bits);
359: }
360: }
361: /* update L2 table */
362: tmp = cpu_to_be64(cluster_offset);
363: l2_table[l2_index] = tmp;
1.1.1.3 root 364: if (bdrv_pwrite_sync(bs->file, l2_offset + l2_index * sizeof(tmp),
1.1.1.2 root 365: &tmp, sizeof(tmp)) < 0)
1.1 root 366: return 0;
367: }
368: return cluster_offset;
369: }
370:
371: static int qcow_is_allocated(BlockDriverState *bs, int64_t sector_num,
372: int nb_sectors, int *pnum)
373: {
374: BDRVQcowState *s = bs->opaque;
375: int index_in_cluster, n;
376: uint64_t cluster_offset;
377:
378: cluster_offset = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0);
379: index_in_cluster = sector_num & (s->cluster_sectors - 1);
380: n = s->cluster_sectors - index_in_cluster;
381: if (n > nb_sectors)
382: n = nb_sectors;
383: *pnum = n;
384: return (cluster_offset != 0);
385: }
386:
387: static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
388: const uint8_t *buf, int buf_size)
389: {
390: z_stream strm1, *strm = &strm1;
391: int ret, out_len;
392:
393: memset(strm, 0, sizeof(*strm));
394:
395: strm->next_in = (uint8_t *)buf;
396: strm->avail_in = buf_size;
397: strm->next_out = out_buf;
398: strm->avail_out = out_buf_size;
399:
400: ret = inflateInit2(strm, -12);
401: if (ret != Z_OK)
402: return -1;
403: ret = inflate(strm, Z_FINISH);
404: out_len = strm->next_out - out_buf;
405: if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
406: out_len != out_buf_size) {
407: inflateEnd(strm);
408: return -1;
409: }
410: inflateEnd(strm);
411: return 0;
412: }
413:
1.1.1.3 root 414: static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
1.1 root 415: {
1.1.1.3 root 416: BDRVQcowState *s = bs->opaque;
1.1 root 417: int ret, csize;
418: uint64_t coffset;
419:
420: coffset = cluster_offset & s->cluster_offset_mask;
421: if (s->cluster_cache_offset != coffset) {
422: csize = cluster_offset >> (63 - s->cluster_bits);
423: csize &= (s->cluster_size - 1);
1.1.1.3 root 424: ret = bdrv_pread(bs->file, coffset, s->cluster_data, csize);
1.1 root 425: if (ret != csize)
426: return -1;
427: if (decompress_buffer(s->cluster_cache, s->cluster_size,
428: s->cluster_data, csize) < 0) {
429: return -1;
430: }
431: s->cluster_cache_offset = coffset;
432: }
433: return 0;
434: }
435:
1.1.1.6 ! root 436: static int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
! 437: int nb_sectors, QEMUIOVector *qiov)
1.1 root 438: {
439: BDRVQcowState *s = bs->opaque;
1.1.1.6 ! root 440: int index_in_cluster;
! 441: int ret = 0, n;
1.1 root 442: uint64_t cluster_offset;
1.1.1.6 ! root 443: struct iovec hd_iov;
! 444: QEMUIOVector hd_qiov;
! 445: uint8_t *buf;
! 446: void *orig_buf;
1.1 root 447:
1.1.1.6 ! root 448: if (qiov->niov > 1) {
! 449: buf = orig_buf = qemu_blockalign(bs, qiov->size);
! 450: } else {
! 451: orig_buf = NULL;
! 452: buf = (uint8_t *)qiov->iov->iov_base;
! 453: }
! 454:
! 455: qemu_co_mutex_lock(&s->lock);
! 456:
! 457: while (nb_sectors != 0) {
! 458: /* prepare next request */
! 459: cluster_offset = get_cluster_offset(bs, sector_num << 9,
! 460: 0, 0, 0, 0);
1.1 root 461: index_in_cluster = sector_num & (s->cluster_sectors - 1);
462: n = s->cluster_sectors - index_in_cluster;
1.1.1.6 ! root 463: if (n > nb_sectors) {
1.1 root 464: n = nb_sectors;
1.1.1.6 ! root 465: }
! 466:
1.1 root 467: if (!cluster_offset) {
468: if (bs->backing_hd) {
469: /* read from the base image */
1.1.1.6 ! root 470: hd_iov.iov_base = (void *)buf;
! 471: hd_iov.iov_len = n * 512;
! 472: qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
! 473: qemu_co_mutex_unlock(&s->lock);
! 474: ret = bdrv_co_readv(bs->backing_hd, sector_num,
! 475: n, &hd_qiov);
! 476: qemu_co_mutex_lock(&s->lock);
! 477: if (ret < 0) {
! 478: goto fail;
! 479: }
1.1 root 480: } else {
1.1.1.6 ! root 481: /* Note: in this case, no need to wait */
1.1 root 482: memset(buf, 0, 512 * n);
483: }
484: } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
1.1.1.6 ! root 485: /* add AIO support for compressed blocks ? */
! 486: if (decompress_cluster(bs, cluster_offset) < 0) {
! 487: goto fail;
! 488: }
! 489: memcpy(buf,
! 490: s->cluster_cache + index_in_cluster * 512, 512 * n);
1.1 root 491: } else {
1.1.1.6 ! root 492: if ((cluster_offset & 511) != 0) {
! 493: goto fail;
! 494: }
! 495: hd_iov.iov_base = (void *)buf;
! 496: hd_iov.iov_len = n * 512;
! 497: qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
! 498: qemu_co_mutex_unlock(&s->lock);
! 499: ret = bdrv_co_readv(bs->file,
! 500: (cluster_offset >> 9) + index_in_cluster,
! 501: n, &hd_qiov);
! 502: qemu_co_mutex_lock(&s->lock);
! 503: if (ret < 0) {
! 504: break;
! 505: }
1.1 root 506: if (s->crypt_method) {
1.1.1.6 ! root 507: encrypt_sectors(s, sector_num, buf, buf,
! 508: n, 0,
1.1 root 509: &s->aes_decrypt_key);
510: }
511: }
1.1.1.6 ! root 512: ret = 0;
! 513:
1.1 root 514: nb_sectors -= n;
515: sector_num += n;
516: buf += n * 512;
517: }
518:
1.1.1.6 ! root 519: done:
! 520: qemu_co_mutex_unlock(&s->lock);
1.1.1.5 root 521:
1.1 root 522: if (qiov->niov > 1) {
1.1.1.6 ! root 523: qemu_iovec_from_buffer(qiov, orig_buf, qiov->size);
! 524: qemu_vfree(orig_buf);
1.1 root 525: }
1.1.1.5 root 526:
1.1.1.6 ! root 527: return ret;
1.1.1.5 root 528:
1.1.1.6 ! root 529: fail:
! 530: ret = -EIO;
! 531: goto done;
1.1.1.5 root 532: }
533:
1.1.1.6 ! root 534: static int qcow_co_writev(BlockDriverState *bs, int64_t sector_num,
! 535: int nb_sectors, QEMUIOVector *qiov)
1.1.1.5 root 536: {
1.1 root 537: BDRVQcowState *s = bs->opaque;
538: int index_in_cluster;
1.1.1.6 ! root 539: uint64_t cluster_offset;
! 540: const uint8_t *src_buf;
! 541: int ret = 0, n;
! 542: uint8_t *cluster_data = NULL;
! 543: struct iovec hd_iov;
! 544: QEMUIOVector hd_qiov;
! 545: uint8_t *buf;
! 546: void *orig_buf;
1.1 root 547:
1.1.1.6 ! root 548: s->cluster_cache_offset = -1; /* disable compressed cache */
1.1 root 549:
1.1.1.6 ! root 550: if (qiov->niov > 1) {
! 551: buf = orig_buf = qemu_blockalign(bs, qiov->size);
! 552: qemu_iovec_to_buffer(qiov, buf);
1.1 root 553: } else {
1.1.1.6 ! root 554: orig_buf = NULL;
! 555: buf = (uint8_t *)qiov->iov->iov_base;
1.1 root 556: }
557:
1.1.1.6 ! root 558: qemu_co_mutex_lock(&s->lock);
1.1 root 559:
1.1.1.6 ! root 560: while (nb_sectors != 0) {
1.1 root 561:
1.1.1.6 ! root 562: index_in_cluster = sector_num & (s->cluster_sectors - 1);
! 563: n = s->cluster_sectors - index_in_cluster;
! 564: if (n > nb_sectors) {
! 565: n = nb_sectors;
1.1.1.5 root 566: }
1.1.1.6 ! root 567: cluster_offset = get_cluster_offset(bs, sector_num << 9, 1, 0,
! 568: index_in_cluster,
! 569: index_in_cluster + n);
! 570: if (!cluster_offset || (cluster_offset & 511) != 0) {
1.1 root 571: ret = -EIO;
1.1.1.6 ! root 572: break;
1.1 root 573: }
1.1.1.6 ! root 574: if (s->crypt_method) {
! 575: if (!cluster_data) {
! 576: cluster_data = g_malloc0(s->cluster_size);
! 577: }
! 578: encrypt_sectors(s, sector_num, cluster_data, buf,
! 579: n, 1, &s->aes_encrypt_key);
! 580: src_buf = cluster_data;
! 581: } else {
! 582: src_buf = buf;
1.1.1.5 root 583: }
1.1 root 584:
1.1.1.6 ! root 585: hd_iov.iov_base = (void *)src_buf;
! 586: hd_iov.iov_len = n * 512;
! 587: qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
! 588: qemu_co_mutex_unlock(&s->lock);
! 589: ret = bdrv_co_writev(bs->file,
! 590: (cluster_offset >> 9) + index_in_cluster,
! 591: n, &hd_qiov);
! 592: qemu_co_mutex_lock(&s->lock);
! 593: if (ret < 0) {
! 594: break;
1.1.1.5 root 595: }
1.1 root 596: ret = 0;
597:
1.1.1.6 ! root 598: nb_sectors -= n;
! 599: sector_num += n;
! 600: buf += n * 512;
1.1 root 601: }
1.1.1.6 ! root 602: qemu_co_mutex_unlock(&s->lock);
1.1 root 603:
1.1.1.6 ! root 604: if (qiov->niov > 1) {
! 605: qemu_vfree(orig_buf);
1.1.1.5 root 606: }
1.1.1.6 ! root 607: g_free(cluster_data);
1.1 root 608:
1.1.1.6 ! root 609: return ret;
1.1 root 610: }
611:
1.1.1.6 ! root 612: static void qcow_close(BlockDriverState *bs)
1.1 root 613: {
614: BDRVQcowState *s = bs->opaque;
615:
1.1.1.6 ! root 616: g_free(s->l1_table);
! 617: g_free(s->l2_cache);
! 618: g_free(s->cluster_cache);
! 619: g_free(s->cluster_data);
1.1 root 620:
1.1.1.6 ! root 621: migrate_del_blocker(s->migration_blocker);
! 622: error_free(s->migration_blocker);
1.1 root 623: }
624:
625: static int qcow_create(const char *filename, QEMUOptionParameter *options)
626: {
627: int fd, header_size, backing_filename_len, l1_size, i, shift;
628: QCowHeader header;
629: uint64_t tmp;
630: int64_t total_size = 0;
631: const char *backing_file = NULL;
632: int flags = 0;
1.1.1.3 root 633: int ret;
1.1 root 634:
635: /* Read out options */
636: while (options && options->name) {
637: if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
638: total_size = options->value.n / 512;
639: } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
640: backing_file = options->value.s;
641: } else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) {
642: flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0;
643: }
644: options++;
645: }
646:
647: fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0644);
648: if (fd < 0)
1.1.1.3 root 649: return -errno;
1.1 root 650: memset(&header, 0, sizeof(header));
651: header.magic = cpu_to_be32(QCOW_MAGIC);
652: header.version = cpu_to_be32(QCOW_VERSION);
653: header.size = cpu_to_be64(total_size * 512);
654: header_size = sizeof(header);
655: backing_filename_len = 0;
656: if (backing_file) {
657: if (strcmp(backing_file, "fat:")) {
658: header.backing_file_offset = cpu_to_be64(header_size);
659: backing_filename_len = strlen(backing_file);
660: header.backing_file_size = cpu_to_be32(backing_filename_len);
661: header_size += backing_filename_len;
662: } else {
663: /* special backing file for vvfat */
664: backing_file = NULL;
665: }
666: header.cluster_bits = 9; /* 512 byte cluster to avoid copying
667: unmodifyed sectors */
668: header.l2_bits = 12; /* 32 KB L2 tables */
669: } else {
670: header.cluster_bits = 12; /* 4 KB clusters */
671: header.l2_bits = 9; /* 4 KB L2 tables */
672: }
673: header_size = (header_size + 7) & ~7;
674: shift = header.cluster_bits + header.l2_bits;
675: l1_size = ((total_size * 512) + (1LL << shift) - 1) >> shift;
676:
677: header.l1_table_offset = cpu_to_be64(header_size);
678: if (flags & BLOCK_FLAG_ENCRYPT) {
679: header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
680: } else {
681: header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
682: }
683:
684: /* write all the data */
1.1.1.3 root 685: ret = qemu_write_full(fd, &header, sizeof(header));
686: if (ret != sizeof(header)) {
687: ret = -errno;
688: goto exit;
689: }
690:
1.1 root 691: if (backing_file) {
1.1.1.3 root 692: ret = qemu_write_full(fd, backing_file, backing_filename_len);
693: if (ret != backing_filename_len) {
694: ret = -errno;
695: goto exit;
696: }
697:
1.1 root 698: }
699: lseek(fd, header_size, SEEK_SET);
700: tmp = 0;
701: for(i = 0;i < l1_size; i++) {
1.1.1.3 root 702: ret = qemu_write_full(fd, &tmp, sizeof(tmp));
703: if (ret != sizeof(tmp)) {
704: ret = -errno;
705: goto exit;
706: }
1.1 root 707: }
1.1.1.3 root 708:
709: ret = 0;
710: exit:
1.1 root 711: close(fd);
1.1.1.3 root 712: return ret;
1.1 root 713: }
714:
715: static int qcow_make_empty(BlockDriverState *bs)
716: {
717: BDRVQcowState *s = bs->opaque;
718: uint32_t l1_length = s->l1_size * sizeof(uint64_t);
719: int ret;
720:
721: memset(s->l1_table, 0, l1_length);
1.1.1.3 root 722: if (bdrv_pwrite_sync(bs->file, s->l1_table_offset, s->l1_table,
1.1.1.2 root 723: l1_length) < 0)
724: return -1;
1.1.1.3 root 725: ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length);
1.1 root 726: if (ret < 0)
727: return ret;
728:
729: memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
730: memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t));
731: memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t));
732:
733: return 0;
734: }
735:
736: /* XXX: put compressed sectors first, then all the cluster aligned
737: tables to avoid losing bytes in alignment */
738: static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
739: const uint8_t *buf, int nb_sectors)
740: {
741: BDRVQcowState *s = bs->opaque;
742: z_stream strm;
743: int ret, out_len;
744: uint8_t *out_buf;
745: uint64_t cluster_offset;
746:
747: if (nb_sectors != s->cluster_sectors)
748: return -EINVAL;
749:
1.1.1.6 ! root 750: out_buf = g_malloc(s->cluster_size + (s->cluster_size / 1000) + 128);
1.1 root 751:
752: /* best compression, small window, no zlib header */
753: memset(&strm, 0, sizeof(strm));
754: ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION,
755: Z_DEFLATED, -12,
756: 9, Z_DEFAULT_STRATEGY);
757: if (ret != 0) {
1.1.1.6 ! root 758: ret = -EINVAL;
! 759: goto fail;
1.1 root 760: }
761:
762: strm.avail_in = s->cluster_size;
763: strm.next_in = (uint8_t *)buf;
764: strm.avail_out = s->cluster_size;
765: strm.next_out = out_buf;
766:
767: ret = deflate(&strm, Z_FINISH);
768: if (ret != Z_STREAM_END && ret != Z_OK) {
769: deflateEnd(&strm);
1.1.1.6 ! root 770: ret = -EINVAL;
! 771: goto fail;
1.1 root 772: }
773: out_len = strm.next_out - out_buf;
774:
775: deflateEnd(&strm);
776:
777: if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
778: /* could not compress: write normal cluster */
1.1.1.6 ! root 779: ret = bdrv_write(bs, sector_num, buf, s->cluster_sectors);
! 780: if (ret < 0) {
! 781: goto fail;
! 782: }
1.1 root 783: } else {
784: cluster_offset = get_cluster_offset(bs, sector_num << 9, 2,
785: out_len, 0, 0);
1.1.1.6 ! root 786: if (cluster_offset == 0) {
! 787: ret = -EIO;
! 788: goto fail;
! 789: }
! 790:
1.1 root 791: cluster_offset &= s->cluster_offset_mask;
1.1.1.6 ! root 792: ret = bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len);
! 793: if (ret < 0) {
! 794: goto fail;
1.1 root 795: }
796: }
797:
1.1.1.6 ! root 798: ret = 0;
! 799: fail:
! 800: g_free(out_buf);
! 801: return ret;
1.1.1.3 root 802: }
803:
1.1.1.6 ! root 804: static coroutine_fn int qcow_co_flush(BlockDriverState *bs)
1.1.1.3 root 805: {
1.1.1.6 ! root 806: return bdrv_co_flush(bs->file);
1.1 root 807: }
808:
809: static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
810: {
811: BDRVQcowState *s = bs->opaque;
812: bdi->cluster_size = s->cluster_size;
813: return 0;
814: }
815:
816:
817: static QEMUOptionParameter qcow_create_options[] = {
818: {
819: .name = BLOCK_OPT_SIZE,
820: .type = OPT_SIZE,
821: .help = "Virtual disk size"
822: },
823: {
824: .name = BLOCK_OPT_BACKING_FILE,
825: .type = OPT_STRING,
826: .help = "File name of a base image"
827: },
828: {
829: .name = BLOCK_OPT_ENCRYPT,
830: .type = OPT_FLAG,
831: .help = "Encrypt the image"
832: },
833: { NULL }
834: };
835:
836: static BlockDriver bdrv_qcow = {
837: .format_name = "qcow",
838: .instance_size = sizeof(BDRVQcowState),
839: .bdrv_probe = qcow_probe,
840: .bdrv_open = qcow_open,
841: .bdrv_close = qcow_close,
842: .bdrv_create = qcow_create,
1.1.1.6 ! root 843:
! 844: .bdrv_co_readv = qcow_co_readv,
! 845: .bdrv_co_writev = qcow_co_writev,
! 846: .bdrv_co_flush_to_disk = qcow_co_flush,
! 847: .bdrv_is_allocated = qcow_is_allocated,
! 848:
! 849: .bdrv_set_key = qcow_set_key,
! 850: .bdrv_make_empty = qcow_make_empty,
! 851: .bdrv_write_compressed = qcow_write_compressed,
! 852: .bdrv_get_info = qcow_get_info,
1.1 root 853:
854: .create_options = qcow_create_options,
855: };
856:
857: static void bdrv_qcow_init(void)
858: {
859: bdrv_register(&bdrv_qcow);
860: }
861:
862: block_init(bdrv_qcow_init);
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