1 /* 2 * QEMU Block driver for RADOS (Ceph) 3 * 4 * Copyright (C) 2010-2011 Christian Brunner <chb@muc.de>, 5 * Josh Durgin <josh.durgin@dreamhost.com> 6 * 7 * This work is licensed under the terms of the GNU GPL, version 2. See 8 * the COPYING file in the top-level directory. 9 * 10 * Contributions after 2012-01-13 are licensed under the terms of the 11 * GNU GPL, version 2 or (at your option) any later version. 12 */ 13 14 #include "qemu/osdep.h" 15 16 #include "qemu-common.h" 17 #include "qemu/error-report.h" 18 #include "block/block_int.h" 19 20 #include <rbd/librbd.h> 21 22 /* 23 * When specifying the image filename use: 24 * 25 * rbd:poolname/devicename[@snapshotname][:option1=value1[:option2=value2...]] 26 * 27 * poolname must be the name of an existing rados pool. 28 * 29 * devicename is the name of the rbd image. 30 * 31 * Each option given is used to configure rados, and may be any valid 32 * Ceph option, "id", or "conf". 33 * 34 * The "id" option indicates what user we should authenticate as to 35 * the Ceph cluster. If it is excluded we will use the Ceph default 36 * (normally 'admin'). 37 * 38 * The "conf" option specifies a Ceph configuration file to read. If 39 * it is not specified, we will read from the default Ceph locations 40 * (e.g., /etc/ceph/ceph.conf). To avoid reading _any_ configuration 41 * file, specify conf=/dev/null. 42 * 43 * Configuration values containing :, @, or = can be escaped with a 44 * leading "\". 45 */ 46 47 /* rbd_aio_discard added in 0.1.2 */ 48 #if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 2) 49 #define LIBRBD_SUPPORTS_DISCARD 50 #else 51 #undef LIBRBD_SUPPORTS_DISCARD 52 #endif 53 54 #define OBJ_MAX_SIZE (1UL << OBJ_DEFAULT_OBJ_ORDER) 55 56 #define RBD_MAX_CONF_NAME_SIZE 128 57 #define RBD_MAX_CONF_VAL_SIZE 512 58 #define RBD_MAX_CONF_SIZE 1024 59 #define RBD_MAX_POOL_NAME_SIZE 128 60 #define RBD_MAX_SNAP_NAME_SIZE 128 61 #define RBD_MAX_SNAPS 100 62 63 typedef enum { 64 RBD_AIO_READ, 65 RBD_AIO_WRITE, 66 RBD_AIO_DISCARD, 67 RBD_AIO_FLUSH 68 } RBDAIOCmd; 69 70 typedef struct RBDAIOCB { 71 BlockAIOCB common; 72 QEMUBH *bh; 73 int64_t ret; 74 QEMUIOVector *qiov; 75 char *bounce; 76 RBDAIOCmd cmd; 77 int error; 78 struct BDRVRBDState *s; 79 } RBDAIOCB; 80 81 typedef struct RADOSCB { 82 RBDAIOCB *acb; 83 struct BDRVRBDState *s; 84 int64_t size; 85 char *buf; 86 int64_t ret; 87 } RADOSCB; 88 89 typedef struct BDRVRBDState { 90 rados_t cluster; 91 rados_ioctx_t io_ctx; 92 rbd_image_t image; 93 char name[RBD_MAX_IMAGE_NAME_SIZE]; 94 char *snap; 95 } BDRVRBDState; 96 97 static int qemu_rbd_next_tok(char *dst, int dst_len, 98 char *src, char delim, 99 const char *name, 100 char **p, Error **errp) 101 { 102 int l; 103 char *end; 104 105 *p = NULL; 106 107 if (delim != '\0') { 108 for (end = src; *end; ++end) { 109 if (*end == delim) { 110 break; 111 } 112 if (*end == '\\' && end[1] != '\0') { 113 end++; 114 } 115 } 116 if (*end == delim) { 117 *p = end + 1; 118 *end = '\0'; 119 } 120 } 121 l = strlen(src); 122 if (l >= dst_len) { 123 error_setg(errp, "%s too long", name); 124 return -EINVAL; 125 } else if (l == 0) { 126 error_setg(errp, "%s too short", name); 127 return -EINVAL; 128 } 129 130 pstrcpy(dst, dst_len, src); 131 132 return 0; 133 } 134 135 static void qemu_rbd_unescape(char *src) 136 { 137 char *p; 138 139 for (p = src; *src; ++src, ++p) { 140 if (*src == '\\' && src[1] != '\0') { 141 src++; 142 } 143 *p = *src; 144 } 145 *p = '\0'; 146 } 147 148 static int qemu_rbd_parsename(const char *filename, 149 char *pool, int pool_len, 150 char *snap, int snap_len, 151 char *name, int name_len, 152 char *conf, int conf_len, 153 Error **errp) 154 { 155 const char *start; 156 char *p, *buf; 157 int ret; 158 159 if (!strstart(filename, "rbd:", &start)) { 160 error_setg(errp, "File name must start with 'rbd:'"); 161 return -EINVAL; 162 } 163 164 buf = g_strdup(start); 165 p = buf; 166 *snap = '\0'; 167 *conf = '\0'; 168 169 ret = qemu_rbd_next_tok(pool, pool_len, p, 170 '/', "pool name", &p, errp); 171 if (ret < 0 || !p) { 172 ret = -EINVAL; 173 goto done; 174 } 175 qemu_rbd_unescape(pool); 176 177 if (strchr(p, '@')) { 178 ret = qemu_rbd_next_tok(name, name_len, p, 179 '@', "object name", &p, errp); 180 if (ret < 0) { 181 goto done; 182 } 183 ret = qemu_rbd_next_tok(snap, snap_len, p, 184 ':', "snap name", &p, errp); 185 qemu_rbd_unescape(snap); 186 } else { 187 ret = qemu_rbd_next_tok(name, name_len, p, 188 ':', "object name", &p, errp); 189 } 190 qemu_rbd_unescape(name); 191 if (ret < 0 || !p) { 192 goto done; 193 } 194 195 ret = qemu_rbd_next_tok(conf, conf_len, p, 196 '\0', "configuration", &p, errp); 197 198 done: 199 g_free(buf); 200 return ret; 201 } 202 203 static char *qemu_rbd_parse_clientname(const char *conf, char *clientname) 204 { 205 const char *p = conf; 206 207 while (*p) { 208 int len; 209 const char *end = strchr(p, ':'); 210 211 if (end) { 212 len = end - p; 213 } else { 214 len = strlen(p); 215 } 216 217 if (strncmp(p, "id=", 3) == 0) { 218 len -= 3; 219 strncpy(clientname, p + 3, len); 220 clientname[len] = '\0'; 221 return clientname; 222 } 223 if (end == NULL) { 224 break; 225 } 226 p = end + 1; 227 } 228 return NULL; 229 } 230 231 static int qemu_rbd_set_conf(rados_t cluster, const char *conf, 232 bool only_read_conf_file, 233 Error **errp) 234 { 235 char *p, *buf; 236 char name[RBD_MAX_CONF_NAME_SIZE]; 237 char value[RBD_MAX_CONF_VAL_SIZE]; 238 int ret = 0; 239 240 buf = g_strdup(conf); 241 p = buf; 242 243 while (p) { 244 ret = qemu_rbd_next_tok(name, sizeof(name), p, 245 '=', "conf option name", &p, errp); 246 if (ret < 0) { 247 break; 248 } 249 qemu_rbd_unescape(name); 250 251 if (!p) { 252 error_setg(errp, "conf option %s has no value", name); 253 ret = -EINVAL; 254 break; 255 } 256 257 ret = qemu_rbd_next_tok(value, sizeof(value), p, 258 ':', "conf option value", &p, errp); 259 if (ret < 0) { 260 break; 261 } 262 qemu_rbd_unescape(value); 263 264 if (strcmp(name, "conf") == 0) { 265 /* read the conf file alone, so it doesn't override more 266 specific settings for a particular device */ 267 if (only_read_conf_file) { 268 ret = rados_conf_read_file(cluster, value); 269 if (ret < 0) { 270 error_setg(errp, "error reading conf file %s", value); 271 break; 272 } 273 } 274 } else if (strcmp(name, "id") == 0) { 275 /* ignore, this is parsed by qemu_rbd_parse_clientname() */ 276 } else if (!only_read_conf_file) { 277 ret = rados_conf_set(cluster, name, value); 278 if (ret < 0) { 279 error_setg(errp, "invalid conf option %s", name); 280 ret = -EINVAL; 281 break; 282 } 283 } 284 } 285 286 g_free(buf); 287 return ret; 288 } 289 290 static int qemu_rbd_create(const char *filename, QemuOpts *opts, Error **errp) 291 { 292 Error *local_err = NULL; 293 int64_t bytes = 0; 294 int64_t objsize; 295 int obj_order = 0; 296 char pool[RBD_MAX_POOL_NAME_SIZE]; 297 char name[RBD_MAX_IMAGE_NAME_SIZE]; 298 char snap_buf[RBD_MAX_SNAP_NAME_SIZE]; 299 char conf[RBD_MAX_CONF_SIZE]; 300 char clientname_buf[RBD_MAX_CONF_SIZE]; 301 char *clientname; 302 rados_t cluster; 303 rados_ioctx_t io_ctx; 304 int ret; 305 306 if (qemu_rbd_parsename(filename, pool, sizeof(pool), 307 snap_buf, sizeof(snap_buf), 308 name, sizeof(name), 309 conf, sizeof(conf), &local_err) < 0) { 310 error_propagate(errp, local_err); 311 return -EINVAL; 312 } 313 314 /* Read out options */ 315 bytes = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 316 BDRV_SECTOR_SIZE); 317 objsize = qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE, 0); 318 if (objsize) { 319 if ((objsize - 1) & objsize) { /* not a power of 2? */ 320 error_setg(errp, "obj size needs to be power of 2"); 321 return -EINVAL; 322 } 323 if (objsize < 4096) { 324 error_setg(errp, "obj size too small"); 325 return -EINVAL; 326 } 327 obj_order = ctz32(objsize); 328 } 329 330 clientname = qemu_rbd_parse_clientname(conf, clientname_buf); 331 if (rados_create(&cluster, clientname) < 0) { 332 error_setg(errp, "error initializing"); 333 return -EIO; 334 } 335 336 if (strstr(conf, "conf=") == NULL) { 337 /* try default location, but ignore failure */ 338 rados_conf_read_file(cluster, NULL); 339 } else if (conf[0] != '\0' && 340 qemu_rbd_set_conf(cluster, conf, true, &local_err) < 0) { 341 rados_shutdown(cluster); 342 error_propagate(errp, local_err); 343 return -EIO; 344 } 345 346 if (conf[0] != '\0' && 347 qemu_rbd_set_conf(cluster, conf, false, &local_err) < 0) { 348 rados_shutdown(cluster); 349 error_propagate(errp, local_err); 350 return -EIO; 351 } 352 353 if (rados_connect(cluster) < 0) { 354 error_setg(errp, "error connecting"); 355 rados_shutdown(cluster); 356 return -EIO; 357 } 358 359 if (rados_ioctx_create(cluster, pool, &io_ctx) < 0) { 360 error_setg(errp, "error opening pool %s", pool); 361 rados_shutdown(cluster); 362 return -EIO; 363 } 364 365 ret = rbd_create(io_ctx, name, bytes, &obj_order); 366 rados_ioctx_destroy(io_ctx); 367 rados_shutdown(cluster); 368 369 return ret; 370 } 371 372 /* 373 * This aio completion is being called from rbd_finish_bh() and runs in qemu 374 * BH context. 375 */ 376 static void qemu_rbd_complete_aio(RADOSCB *rcb) 377 { 378 RBDAIOCB *acb = rcb->acb; 379 int64_t r; 380 381 r = rcb->ret; 382 383 if (acb->cmd != RBD_AIO_READ) { 384 if (r < 0) { 385 acb->ret = r; 386 acb->error = 1; 387 } else if (!acb->error) { 388 acb->ret = rcb->size; 389 } 390 } else { 391 if (r < 0) { 392 memset(rcb->buf, 0, rcb->size); 393 acb->ret = r; 394 acb->error = 1; 395 } else if (r < rcb->size) { 396 memset(rcb->buf + r, 0, rcb->size - r); 397 if (!acb->error) { 398 acb->ret = rcb->size; 399 } 400 } else if (!acb->error) { 401 acb->ret = r; 402 } 403 } 404 405 g_free(rcb); 406 407 if (acb->cmd == RBD_AIO_READ) { 408 qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size); 409 } 410 qemu_vfree(acb->bounce); 411 acb->common.cb(acb->common.opaque, (acb->ret > 0 ? 0 : acb->ret)); 412 413 qemu_aio_unref(acb); 414 } 415 416 /* TODO Convert to fine grained options */ 417 static QemuOptsList runtime_opts = { 418 .name = "rbd", 419 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 420 .desc = { 421 { 422 .name = "filename", 423 .type = QEMU_OPT_STRING, 424 .help = "Specification of the rbd image", 425 }, 426 { /* end of list */ } 427 }, 428 }; 429 430 static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags, 431 Error **errp) 432 { 433 BDRVRBDState *s = bs->opaque; 434 char pool[RBD_MAX_POOL_NAME_SIZE]; 435 char snap_buf[RBD_MAX_SNAP_NAME_SIZE]; 436 char conf[RBD_MAX_CONF_SIZE]; 437 char clientname_buf[RBD_MAX_CONF_SIZE]; 438 char *clientname; 439 QemuOpts *opts; 440 Error *local_err = NULL; 441 const char *filename; 442 int r; 443 444 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 445 qemu_opts_absorb_qdict(opts, options, &local_err); 446 if (local_err) { 447 error_propagate(errp, local_err); 448 qemu_opts_del(opts); 449 return -EINVAL; 450 } 451 452 filename = qemu_opt_get(opts, "filename"); 453 454 if (qemu_rbd_parsename(filename, pool, sizeof(pool), 455 snap_buf, sizeof(snap_buf), 456 s->name, sizeof(s->name), 457 conf, sizeof(conf), errp) < 0) { 458 r = -EINVAL; 459 goto failed_opts; 460 } 461 462 clientname = qemu_rbd_parse_clientname(conf, clientname_buf); 463 r = rados_create(&s->cluster, clientname); 464 if (r < 0) { 465 error_setg(errp, "error initializing"); 466 goto failed_opts; 467 } 468 469 s->snap = NULL; 470 if (snap_buf[0] != '\0') { 471 s->snap = g_strdup(snap_buf); 472 } 473 474 if (strstr(conf, "conf=") == NULL) { 475 /* try default location, but ignore failure */ 476 rados_conf_read_file(s->cluster, NULL); 477 } else if (conf[0] != '\0') { 478 r = qemu_rbd_set_conf(s->cluster, conf, true, errp); 479 if (r < 0) { 480 goto failed_shutdown; 481 } 482 } 483 484 if (conf[0] != '\0') { 485 r = qemu_rbd_set_conf(s->cluster, conf, false, errp); 486 if (r < 0) { 487 goto failed_shutdown; 488 } 489 } 490 491 /* 492 * Fallback to more conservative semantics if setting cache 493 * options fails. Ignore errors from setting rbd_cache because the 494 * only possible error is that the option does not exist, and 495 * librbd defaults to no caching. If write through caching cannot 496 * be set up, fall back to no caching. 497 */ 498 if (flags & BDRV_O_NOCACHE) { 499 rados_conf_set(s->cluster, "rbd_cache", "false"); 500 } else { 501 rados_conf_set(s->cluster, "rbd_cache", "true"); 502 } 503 504 r = rados_connect(s->cluster); 505 if (r < 0) { 506 error_setg(errp, "error connecting"); 507 goto failed_shutdown; 508 } 509 510 r = rados_ioctx_create(s->cluster, pool, &s->io_ctx); 511 if (r < 0) { 512 error_setg(errp, "error opening pool %s", pool); 513 goto failed_shutdown; 514 } 515 516 r = rbd_open(s->io_ctx, s->name, &s->image, s->snap); 517 if (r < 0) { 518 error_setg(errp, "error reading header from %s", s->name); 519 goto failed_open; 520 } 521 522 bs->read_only = (s->snap != NULL); 523 524 qemu_opts_del(opts); 525 return 0; 526 527 failed_open: 528 rados_ioctx_destroy(s->io_ctx); 529 failed_shutdown: 530 rados_shutdown(s->cluster); 531 g_free(s->snap); 532 failed_opts: 533 qemu_opts_del(opts); 534 return r; 535 } 536 537 static void qemu_rbd_close(BlockDriverState *bs) 538 { 539 BDRVRBDState *s = bs->opaque; 540 541 rbd_close(s->image); 542 rados_ioctx_destroy(s->io_ctx); 543 g_free(s->snap); 544 rados_shutdown(s->cluster); 545 } 546 547 static const AIOCBInfo rbd_aiocb_info = { 548 .aiocb_size = sizeof(RBDAIOCB), 549 }; 550 551 static void rbd_finish_bh(void *opaque) 552 { 553 RADOSCB *rcb = opaque; 554 qemu_bh_delete(rcb->acb->bh); 555 qemu_rbd_complete_aio(rcb); 556 } 557 558 /* 559 * This is the callback function for rbd_aio_read and _write 560 * 561 * Note: this function is being called from a non qemu thread so 562 * we need to be careful about what we do here. Generally we only 563 * schedule a BH, and do the rest of the io completion handling 564 * from rbd_finish_bh() which runs in a qemu context. 565 */ 566 static void rbd_finish_aiocb(rbd_completion_t c, RADOSCB *rcb) 567 { 568 RBDAIOCB *acb = rcb->acb; 569 570 rcb->ret = rbd_aio_get_return_value(c); 571 rbd_aio_release(c); 572 573 acb->bh = aio_bh_new(bdrv_get_aio_context(acb->common.bs), 574 rbd_finish_bh, rcb); 575 qemu_bh_schedule(acb->bh); 576 } 577 578 static int rbd_aio_discard_wrapper(rbd_image_t image, 579 uint64_t off, 580 uint64_t len, 581 rbd_completion_t comp) 582 { 583 #ifdef LIBRBD_SUPPORTS_DISCARD 584 return rbd_aio_discard(image, off, len, comp); 585 #else 586 return -ENOTSUP; 587 #endif 588 } 589 590 static int rbd_aio_flush_wrapper(rbd_image_t image, 591 rbd_completion_t comp) 592 { 593 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH 594 return rbd_aio_flush(image, comp); 595 #else 596 return -ENOTSUP; 597 #endif 598 } 599 600 static BlockAIOCB *rbd_start_aio(BlockDriverState *bs, 601 int64_t sector_num, 602 QEMUIOVector *qiov, 603 int nb_sectors, 604 BlockCompletionFunc *cb, 605 void *opaque, 606 RBDAIOCmd cmd) 607 { 608 RBDAIOCB *acb; 609 RADOSCB *rcb = NULL; 610 rbd_completion_t c; 611 int64_t off, size; 612 char *buf; 613 int r; 614 615 BDRVRBDState *s = bs->opaque; 616 617 acb = qemu_aio_get(&rbd_aiocb_info, bs, cb, opaque); 618 acb->cmd = cmd; 619 acb->qiov = qiov; 620 if (cmd == RBD_AIO_DISCARD || cmd == RBD_AIO_FLUSH) { 621 acb->bounce = NULL; 622 } else { 623 acb->bounce = qemu_try_blockalign(bs, qiov->size); 624 if (acb->bounce == NULL) { 625 goto failed; 626 } 627 } 628 acb->ret = 0; 629 acb->error = 0; 630 acb->s = s; 631 acb->bh = NULL; 632 633 if (cmd == RBD_AIO_WRITE) { 634 qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size); 635 } 636 637 buf = acb->bounce; 638 639 off = sector_num * BDRV_SECTOR_SIZE; 640 size = nb_sectors * BDRV_SECTOR_SIZE; 641 642 rcb = g_new(RADOSCB, 1); 643 rcb->acb = acb; 644 rcb->buf = buf; 645 rcb->s = acb->s; 646 rcb->size = size; 647 r = rbd_aio_create_completion(rcb, (rbd_callback_t) rbd_finish_aiocb, &c); 648 if (r < 0) { 649 goto failed; 650 } 651 652 switch (cmd) { 653 case RBD_AIO_WRITE: 654 r = rbd_aio_write(s->image, off, size, buf, c); 655 break; 656 case RBD_AIO_READ: 657 r = rbd_aio_read(s->image, off, size, buf, c); 658 break; 659 case RBD_AIO_DISCARD: 660 r = rbd_aio_discard_wrapper(s->image, off, size, c); 661 break; 662 case RBD_AIO_FLUSH: 663 r = rbd_aio_flush_wrapper(s->image, c); 664 break; 665 default: 666 r = -EINVAL; 667 } 668 669 if (r < 0) { 670 goto failed_completion; 671 } 672 673 return &acb->common; 674 675 failed_completion: 676 rbd_aio_release(c); 677 failed: 678 g_free(rcb); 679 qemu_vfree(acb->bounce); 680 qemu_aio_unref(acb); 681 return NULL; 682 } 683 684 static BlockAIOCB *qemu_rbd_aio_readv(BlockDriverState *bs, 685 int64_t sector_num, 686 QEMUIOVector *qiov, 687 int nb_sectors, 688 BlockCompletionFunc *cb, 689 void *opaque) 690 { 691 return rbd_start_aio(bs, sector_num, qiov, nb_sectors, cb, opaque, 692 RBD_AIO_READ); 693 } 694 695 static BlockAIOCB *qemu_rbd_aio_writev(BlockDriverState *bs, 696 int64_t sector_num, 697 QEMUIOVector *qiov, 698 int nb_sectors, 699 BlockCompletionFunc *cb, 700 void *opaque) 701 { 702 return rbd_start_aio(bs, sector_num, qiov, nb_sectors, cb, opaque, 703 RBD_AIO_WRITE); 704 } 705 706 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH 707 static BlockAIOCB *qemu_rbd_aio_flush(BlockDriverState *bs, 708 BlockCompletionFunc *cb, 709 void *opaque) 710 { 711 return rbd_start_aio(bs, 0, NULL, 0, cb, opaque, RBD_AIO_FLUSH); 712 } 713 714 #else 715 716 static int qemu_rbd_co_flush(BlockDriverState *bs) 717 { 718 #if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 1) 719 /* rbd_flush added in 0.1.1 */ 720 BDRVRBDState *s = bs->opaque; 721 return rbd_flush(s->image); 722 #else 723 return 0; 724 #endif 725 } 726 #endif 727 728 static int qemu_rbd_getinfo(BlockDriverState *bs, BlockDriverInfo *bdi) 729 { 730 BDRVRBDState *s = bs->opaque; 731 rbd_image_info_t info; 732 int r; 733 734 r = rbd_stat(s->image, &info, sizeof(info)); 735 if (r < 0) { 736 return r; 737 } 738 739 bdi->cluster_size = info.obj_size; 740 return 0; 741 } 742 743 static int64_t qemu_rbd_getlength(BlockDriverState *bs) 744 { 745 BDRVRBDState *s = bs->opaque; 746 rbd_image_info_t info; 747 int r; 748 749 r = rbd_stat(s->image, &info, sizeof(info)); 750 if (r < 0) { 751 return r; 752 } 753 754 return info.size; 755 } 756 757 static int qemu_rbd_truncate(BlockDriverState *bs, int64_t offset) 758 { 759 BDRVRBDState *s = bs->opaque; 760 int r; 761 762 r = rbd_resize(s->image, offset); 763 if (r < 0) { 764 return r; 765 } 766 767 return 0; 768 } 769 770 static int qemu_rbd_snap_create(BlockDriverState *bs, 771 QEMUSnapshotInfo *sn_info) 772 { 773 BDRVRBDState *s = bs->opaque; 774 int r; 775 776 if (sn_info->name[0] == '\0') { 777 return -EINVAL; /* we need a name for rbd snapshots */ 778 } 779 780 /* 781 * rbd snapshots are using the name as the user controlled unique identifier 782 * we can't use the rbd snapid for that purpose, as it can't be set 783 */ 784 if (sn_info->id_str[0] != '\0' && 785 strcmp(sn_info->id_str, sn_info->name) != 0) { 786 return -EINVAL; 787 } 788 789 if (strlen(sn_info->name) >= sizeof(sn_info->id_str)) { 790 return -ERANGE; 791 } 792 793 r = rbd_snap_create(s->image, sn_info->name); 794 if (r < 0) { 795 error_report("failed to create snap: %s", strerror(-r)); 796 return r; 797 } 798 799 return 0; 800 } 801 802 static int qemu_rbd_snap_remove(BlockDriverState *bs, 803 const char *snapshot_id, 804 const char *snapshot_name, 805 Error **errp) 806 { 807 BDRVRBDState *s = bs->opaque; 808 int r; 809 810 if (!snapshot_name) { 811 error_setg(errp, "rbd need a valid snapshot name"); 812 return -EINVAL; 813 } 814 815 /* If snapshot_id is specified, it must be equal to name, see 816 qemu_rbd_snap_list() */ 817 if (snapshot_id && strcmp(snapshot_id, snapshot_name)) { 818 error_setg(errp, 819 "rbd do not support snapshot id, it should be NULL or " 820 "equal to snapshot name"); 821 return -EINVAL; 822 } 823 824 r = rbd_snap_remove(s->image, snapshot_name); 825 if (r < 0) { 826 error_setg_errno(errp, -r, "Failed to remove the snapshot"); 827 } 828 return r; 829 } 830 831 static int qemu_rbd_snap_rollback(BlockDriverState *bs, 832 const char *snapshot_name) 833 { 834 BDRVRBDState *s = bs->opaque; 835 int r; 836 837 r = rbd_snap_rollback(s->image, snapshot_name); 838 return r; 839 } 840 841 static int qemu_rbd_snap_list(BlockDriverState *bs, 842 QEMUSnapshotInfo **psn_tab) 843 { 844 BDRVRBDState *s = bs->opaque; 845 QEMUSnapshotInfo *sn_info, *sn_tab = NULL; 846 int i, snap_count; 847 rbd_snap_info_t *snaps; 848 int max_snaps = RBD_MAX_SNAPS; 849 850 do { 851 snaps = g_new(rbd_snap_info_t, max_snaps); 852 snap_count = rbd_snap_list(s->image, snaps, &max_snaps); 853 if (snap_count <= 0) { 854 g_free(snaps); 855 } 856 } while (snap_count == -ERANGE); 857 858 if (snap_count <= 0) { 859 goto done; 860 } 861 862 sn_tab = g_new0(QEMUSnapshotInfo, snap_count); 863 864 for (i = 0; i < snap_count; i++) { 865 const char *snap_name = snaps[i].name; 866 867 sn_info = sn_tab + i; 868 pstrcpy(sn_info->id_str, sizeof(sn_info->id_str), snap_name); 869 pstrcpy(sn_info->name, sizeof(sn_info->name), snap_name); 870 871 sn_info->vm_state_size = snaps[i].size; 872 sn_info->date_sec = 0; 873 sn_info->date_nsec = 0; 874 sn_info->vm_clock_nsec = 0; 875 } 876 rbd_snap_list_end(snaps); 877 g_free(snaps); 878 879 done: 880 *psn_tab = sn_tab; 881 return snap_count; 882 } 883 884 #ifdef LIBRBD_SUPPORTS_DISCARD 885 static BlockAIOCB* qemu_rbd_aio_discard(BlockDriverState *bs, 886 int64_t sector_num, 887 int nb_sectors, 888 BlockCompletionFunc *cb, 889 void *opaque) 890 { 891 return rbd_start_aio(bs, sector_num, NULL, nb_sectors, cb, opaque, 892 RBD_AIO_DISCARD); 893 } 894 #endif 895 896 #ifdef LIBRBD_SUPPORTS_INVALIDATE 897 static void qemu_rbd_invalidate_cache(BlockDriverState *bs, 898 Error **errp) 899 { 900 BDRVRBDState *s = bs->opaque; 901 int r = rbd_invalidate_cache(s->image); 902 if (r < 0) { 903 error_setg_errno(errp, -r, "Failed to invalidate the cache"); 904 } 905 } 906 #endif 907 908 static QemuOptsList qemu_rbd_create_opts = { 909 .name = "rbd-create-opts", 910 .head = QTAILQ_HEAD_INITIALIZER(qemu_rbd_create_opts.head), 911 .desc = { 912 { 913 .name = BLOCK_OPT_SIZE, 914 .type = QEMU_OPT_SIZE, 915 .help = "Virtual disk size" 916 }, 917 { 918 .name = BLOCK_OPT_CLUSTER_SIZE, 919 .type = QEMU_OPT_SIZE, 920 .help = "RBD object size" 921 }, 922 { /* end of list */ } 923 } 924 }; 925 926 static BlockDriver bdrv_rbd = { 927 .format_name = "rbd", 928 .instance_size = sizeof(BDRVRBDState), 929 .bdrv_needs_filename = true, 930 .bdrv_file_open = qemu_rbd_open, 931 .bdrv_close = qemu_rbd_close, 932 .bdrv_create = qemu_rbd_create, 933 .bdrv_has_zero_init = bdrv_has_zero_init_1, 934 .bdrv_get_info = qemu_rbd_getinfo, 935 .create_opts = &qemu_rbd_create_opts, 936 .bdrv_getlength = qemu_rbd_getlength, 937 .bdrv_truncate = qemu_rbd_truncate, 938 .protocol_name = "rbd", 939 940 .bdrv_aio_readv = qemu_rbd_aio_readv, 941 .bdrv_aio_writev = qemu_rbd_aio_writev, 942 943 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH 944 .bdrv_aio_flush = qemu_rbd_aio_flush, 945 #else 946 .bdrv_co_flush_to_disk = qemu_rbd_co_flush, 947 #endif 948 949 #ifdef LIBRBD_SUPPORTS_DISCARD 950 .bdrv_aio_discard = qemu_rbd_aio_discard, 951 #endif 952 953 .bdrv_snapshot_create = qemu_rbd_snap_create, 954 .bdrv_snapshot_delete = qemu_rbd_snap_remove, 955 .bdrv_snapshot_list = qemu_rbd_snap_list, 956 .bdrv_snapshot_goto = qemu_rbd_snap_rollback, 957 #ifdef LIBRBD_SUPPORTS_INVALIDATE 958 .bdrv_invalidate_cache = qemu_rbd_invalidate_cache, 959 #endif 960 }; 961 962 static void bdrv_rbd_init(void) 963 { 964 bdrv_register(&bdrv_rbd); 965 } 966 967 block_init(bdrv_rbd_init); 968