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 "qapi/error.h" 17 #include "qemu/error-report.h" 18 #include "block/block_int.h" 19 #include "crypto/secret.h" 20 #include "qemu/cutils.h" 21 22 #include <rbd/librbd.h> 23 24 /* 25 * When specifying the image filename use: 26 * 27 * rbd:poolname/devicename[@snapshotname][:option1=value1[:option2=value2...]] 28 * 29 * poolname must be the name of an existing rados pool. 30 * 31 * devicename is the name of the rbd image. 32 * 33 * Each option given is used to configure rados, and may be any valid 34 * Ceph option, "id", or "conf". 35 * 36 * The "id" option indicates what user we should authenticate as to 37 * the Ceph cluster. If it is excluded we will use the Ceph default 38 * (normally 'admin'). 39 * 40 * The "conf" option specifies a Ceph configuration file to read. If 41 * it is not specified, we will read from the default Ceph locations 42 * (e.g., /etc/ceph/ceph.conf). To avoid reading _any_ configuration 43 * file, specify conf=/dev/null. 44 * 45 * Configuration values containing :, @, or = can be escaped with a 46 * leading "\". 47 */ 48 49 /* rbd_aio_discard added in 0.1.2 */ 50 #if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 2) 51 #define LIBRBD_SUPPORTS_DISCARD 52 #else 53 #undef LIBRBD_SUPPORTS_DISCARD 54 #endif 55 56 #define OBJ_MAX_SIZE (1UL << OBJ_DEFAULT_OBJ_ORDER) 57 58 #define RBD_MAX_CONF_NAME_SIZE 128 59 #define RBD_MAX_CONF_VAL_SIZE 512 60 #define RBD_MAX_CONF_SIZE 1024 61 #define RBD_MAX_POOL_NAME_SIZE 128 62 #define RBD_MAX_SNAP_NAME_SIZE 128 63 #define RBD_MAX_SNAPS 100 64 65 typedef enum { 66 RBD_AIO_READ, 67 RBD_AIO_WRITE, 68 RBD_AIO_DISCARD, 69 RBD_AIO_FLUSH 70 } RBDAIOCmd; 71 72 typedef struct RBDAIOCB { 73 BlockAIOCB common; 74 int64_t ret; 75 QEMUIOVector *qiov; 76 char *bounce; 77 RBDAIOCmd cmd; 78 int error; 79 struct BDRVRBDState *s; 80 } RBDAIOCB; 81 82 typedef struct RADOSCB { 83 RBDAIOCB *acb; 84 struct BDRVRBDState *s; 85 int64_t size; 86 char *buf; 87 int64_t ret; 88 } RADOSCB; 89 90 typedef struct BDRVRBDState { 91 rados_t cluster; 92 rados_ioctx_t io_ctx; 93 rbd_image_t image; 94 char name[RBD_MAX_IMAGE_NAME_SIZE]; 95 char *snap; 96 } BDRVRBDState; 97 98 static int qemu_rbd_next_tok(char *dst, int dst_len, 99 char *src, char delim, 100 const char *name, 101 char **p, Error **errp) 102 { 103 int l; 104 char *end; 105 106 *p = NULL; 107 108 if (delim != '\0') { 109 for (end = src; *end; ++end) { 110 if (*end == delim) { 111 break; 112 } 113 if (*end == '\\' && end[1] != '\0') { 114 end++; 115 } 116 } 117 if (*end == delim) { 118 *p = end + 1; 119 *end = '\0'; 120 } 121 } 122 l = strlen(src); 123 if (l >= dst_len) { 124 error_setg(errp, "%s too long", name); 125 return -EINVAL; 126 } else if (l == 0) { 127 error_setg(errp, "%s too short", name); 128 return -EINVAL; 129 } 130 131 pstrcpy(dst, dst_len, src); 132 133 return 0; 134 } 135 136 static void qemu_rbd_unescape(char *src) 137 { 138 char *p; 139 140 for (p = src; *src; ++src, ++p) { 141 if (*src == '\\' && src[1] != '\0') { 142 src++; 143 } 144 *p = *src; 145 } 146 *p = '\0'; 147 } 148 149 static int qemu_rbd_parsename(const char *filename, 150 char *pool, int pool_len, 151 char *snap, int snap_len, 152 char *name, int name_len, 153 char *conf, int conf_len, 154 Error **errp) 155 { 156 const char *start; 157 char *p, *buf; 158 int ret; 159 160 if (!strstart(filename, "rbd:", &start)) { 161 error_setg(errp, "File name must start with 'rbd:'"); 162 return -EINVAL; 163 } 164 165 buf = g_strdup(start); 166 p = buf; 167 *snap = '\0'; 168 *conf = '\0'; 169 170 ret = qemu_rbd_next_tok(pool, pool_len, p, 171 '/', "pool name", &p, errp); 172 if (ret < 0 || !p) { 173 ret = -EINVAL; 174 goto done; 175 } 176 qemu_rbd_unescape(pool); 177 178 if (strchr(p, '@')) { 179 ret = qemu_rbd_next_tok(name, name_len, p, 180 '@', "object name", &p, errp); 181 if (ret < 0) { 182 goto done; 183 } 184 ret = qemu_rbd_next_tok(snap, snap_len, p, 185 ':', "snap name", &p, errp); 186 qemu_rbd_unescape(snap); 187 } else { 188 ret = qemu_rbd_next_tok(name, name_len, p, 189 ':', "object name", &p, errp); 190 } 191 qemu_rbd_unescape(name); 192 if (ret < 0 || !p) { 193 goto done; 194 } 195 196 ret = qemu_rbd_next_tok(conf, conf_len, p, 197 '\0', "configuration", &p, errp); 198 199 done: 200 g_free(buf); 201 return ret; 202 } 203 204 static char *qemu_rbd_parse_clientname(const char *conf, char *clientname) 205 { 206 const char *p = conf; 207 208 while (*p) { 209 int len; 210 const char *end = strchr(p, ':'); 211 212 if (end) { 213 len = end - p; 214 } else { 215 len = strlen(p); 216 } 217 218 if (strncmp(p, "id=", 3) == 0) { 219 len -= 3; 220 strncpy(clientname, p + 3, len); 221 clientname[len] = '\0'; 222 return clientname; 223 } 224 if (end == NULL) { 225 break; 226 } 227 p = end + 1; 228 } 229 return NULL; 230 } 231 232 233 static int qemu_rbd_set_auth(rados_t cluster, const char *secretid, 234 Error **errp) 235 { 236 if (secretid == 0) { 237 return 0; 238 } 239 240 gchar *secret = qcrypto_secret_lookup_as_base64(secretid, 241 errp); 242 if (!secret) { 243 return -1; 244 } 245 246 rados_conf_set(cluster, "key", secret); 247 g_free(secret); 248 249 return 0; 250 } 251 252 253 static int qemu_rbd_set_conf(rados_t cluster, const char *conf, 254 bool only_read_conf_file, 255 Error **errp) 256 { 257 char *p, *buf; 258 char name[RBD_MAX_CONF_NAME_SIZE]; 259 char value[RBD_MAX_CONF_VAL_SIZE]; 260 int ret = 0; 261 262 buf = g_strdup(conf); 263 p = buf; 264 265 while (p) { 266 ret = qemu_rbd_next_tok(name, sizeof(name), p, 267 '=', "conf option name", &p, errp); 268 if (ret < 0) { 269 break; 270 } 271 qemu_rbd_unescape(name); 272 273 if (!p) { 274 error_setg(errp, "conf option %s has no value", name); 275 ret = -EINVAL; 276 break; 277 } 278 279 ret = qemu_rbd_next_tok(value, sizeof(value), p, 280 ':', "conf option value", &p, errp); 281 if (ret < 0) { 282 break; 283 } 284 qemu_rbd_unescape(value); 285 286 if (strcmp(name, "conf") == 0) { 287 /* read the conf file alone, so it doesn't override more 288 specific settings for a particular device */ 289 if (only_read_conf_file) { 290 ret = rados_conf_read_file(cluster, value); 291 if (ret < 0) { 292 error_setg_errno(errp, -ret, "error reading conf file %s", 293 value); 294 break; 295 } 296 } 297 } else if (strcmp(name, "id") == 0) { 298 /* ignore, this is parsed by qemu_rbd_parse_clientname() */ 299 } else if (!only_read_conf_file) { 300 ret = rados_conf_set(cluster, name, value); 301 if (ret < 0) { 302 error_setg_errno(errp, -ret, "invalid conf option %s", name); 303 ret = -EINVAL; 304 break; 305 } 306 } 307 } 308 309 g_free(buf); 310 return ret; 311 } 312 313 static int qemu_rbd_create(const char *filename, QemuOpts *opts, Error **errp) 314 { 315 Error *local_err = NULL; 316 int64_t bytes = 0; 317 int64_t objsize; 318 int obj_order = 0; 319 char pool[RBD_MAX_POOL_NAME_SIZE]; 320 char name[RBD_MAX_IMAGE_NAME_SIZE]; 321 char snap_buf[RBD_MAX_SNAP_NAME_SIZE]; 322 char conf[RBD_MAX_CONF_SIZE]; 323 char clientname_buf[RBD_MAX_CONF_SIZE]; 324 char *clientname; 325 const char *secretid; 326 rados_t cluster; 327 rados_ioctx_t io_ctx; 328 int ret; 329 330 secretid = qemu_opt_get(opts, "password-secret"); 331 332 if (qemu_rbd_parsename(filename, pool, sizeof(pool), 333 snap_buf, sizeof(snap_buf), 334 name, sizeof(name), 335 conf, sizeof(conf), &local_err) < 0) { 336 error_propagate(errp, local_err); 337 return -EINVAL; 338 } 339 340 /* Read out options */ 341 bytes = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 342 BDRV_SECTOR_SIZE); 343 objsize = qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE, 0); 344 if (objsize) { 345 if ((objsize - 1) & objsize) { /* not a power of 2? */ 346 error_setg(errp, "obj size needs to be power of 2"); 347 return -EINVAL; 348 } 349 if (objsize < 4096) { 350 error_setg(errp, "obj size too small"); 351 return -EINVAL; 352 } 353 obj_order = ctz32(objsize); 354 } 355 356 clientname = qemu_rbd_parse_clientname(conf, clientname_buf); 357 ret = rados_create(&cluster, clientname); 358 if (ret < 0) { 359 error_setg_errno(errp, -ret, "error initializing"); 360 return ret; 361 } 362 363 if (strstr(conf, "conf=") == NULL) { 364 /* try default location, but ignore failure */ 365 rados_conf_read_file(cluster, NULL); 366 } else if (conf[0] != '\0' && 367 qemu_rbd_set_conf(cluster, conf, true, &local_err) < 0) { 368 error_propagate(errp, local_err); 369 ret = -EIO; 370 goto shutdown; 371 } 372 373 if (conf[0] != '\0' && 374 qemu_rbd_set_conf(cluster, conf, false, &local_err) < 0) { 375 error_propagate(errp, local_err); 376 ret = -EIO; 377 goto shutdown; 378 } 379 380 if (qemu_rbd_set_auth(cluster, secretid, errp) < 0) { 381 ret = -EIO; 382 goto shutdown; 383 } 384 385 ret = rados_connect(cluster); 386 if (ret < 0) { 387 error_setg_errno(errp, -ret, "error connecting"); 388 goto shutdown; 389 } 390 391 ret = rados_ioctx_create(cluster, pool, &io_ctx); 392 if (ret < 0) { 393 error_setg_errno(errp, -ret, "error opening pool %s", pool); 394 goto shutdown; 395 } 396 397 ret = rbd_create(io_ctx, name, bytes, &obj_order); 398 if (ret < 0) { 399 error_setg_errno(errp, -ret, "error rbd create"); 400 } 401 402 rados_ioctx_destroy(io_ctx); 403 404 shutdown: 405 rados_shutdown(cluster); 406 return ret; 407 } 408 409 /* 410 * This aio completion is being called from rbd_finish_bh() and runs in qemu 411 * BH context. 412 */ 413 static void qemu_rbd_complete_aio(RADOSCB *rcb) 414 { 415 RBDAIOCB *acb = rcb->acb; 416 int64_t r; 417 418 r = rcb->ret; 419 420 if (acb->cmd != RBD_AIO_READ) { 421 if (r < 0) { 422 acb->ret = r; 423 acb->error = 1; 424 } else if (!acb->error) { 425 acb->ret = rcb->size; 426 } 427 } else { 428 if (r < 0) { 429 memset(rcb->buf, 0, rcb->size); 430 acb->ret = r; 431 acb->error = 1; 432 } else if (r < rcb->size) { 433 memset(rcb->buf + r, 0, rcb->size - r); 434 if (!acb->error) { 435 acb->ret = rcb->size; 436 } 437 } else if (!acb->error) { 438 acb->ret = r; 439 } 440 } 441 442 g_free(rcb); 443 444 if (acb->cmd == RBD_AIO_READ) { 445 qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size); 446 } 447 qemu_vfree(acb->bounce); 448 acb->common.cb(acb->common.opaque, (acb->ret > 0 ? 0 : acb->ret)); 449 450 qemu_aio_unref(acb); 451 } 452 453 /* TODO Convert to fine grained options */ 454 static QemuOptsList runtime_opts = { 455 .name = "rbd", 456 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 457 .desc = { 458 { 459 .name = "filename", 460 .type = QEMU_OPT_STRING, 461 .help = "Specification of the rbd image", 462 }, 463 { 464 .name = "password-secret", 465 .type = QEMU_OPT_STRING, 466 .help = "ID of secret providing the password", 467 }, 468 { /* end of list */ } 469 }, 470 }; 471 472 static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags, 473 Error **errp) 474 { 475 BDRVRBDState *s = bs->opaque; 476 char pool[RBD_MAX_POOL_NAME_SIZE]; 477 char snap_buf[RBD_MAX_SNAP_NAME_SIZE]; 478 char conf[RBD_MAX_CONF_SIZE]; 479 char clientname_buf[RBD_MAX_CONF_SIZE]; 480 char *clientname; 481 const char *secretid; 482 QemuOpts *opts; 483 Error *local_err = NULL; 484 const char *filename; 485 int r; 486 487 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 488 qemu_opts_absorb_qdict(opts, options, &local_err); 489 if (local_err) { 490 error_propagate(errp, local_err); 491 qemu_opts_del(opts); 492 return -EINVAL; 493 } 494 495 filename = qemu_opt_get(opts, "filename"); 496 secretid = qemu_opt_get(opts, "password-secret"); 497 498 if (qemu_rbd_parsename(filename, pool, sizeof(pool), 499 snap_buf, sizeof(snap_buf), 500 s->name, sizeof(s->name), 501 conf, sizeof(conf), errp) < 0) { 502 r = -EINVAL; 503 goto failed_opts; 504 } 505 506 clientname = qemu_rbd_parse_clientname(conf, clientname_buf); 507 r = rados_create(&s->cluster, clientname); 508 if (r < 0) { 509 error_setg_errno(errp, -r, "error initializing"); 510 goto failed_opts; 511 } 512 513 s->snap = NULL; 514 if (snap_buf[0] != '\0') { 515 s->snap = g_strdup(snap_buf); 516 } 517 518 if (strstr(conf, "conf=") == NULL) { 519 /* try default location, but ignore failure */ 520 rados_conf_read_file(s->cluster, NULL); 521 } else if (conf[0] != '\0') { 522 r = qemu_rbd_set_conf(s->cluster, conf, true, errp); 523 if (r < 0) { 524 goto failed_shutdown; 525 } 526 } 527 528 if (conf[0] != '\0') { 529 r = qemu_rbd_set_conf(s->cluster, conf, false, errp); 530 if (r < 0) { 531 goto failed_shutdown; 532 } 533 } 534 535 if (qemu_rbd_set_auth(s->cluster, secretid, errp) < 0) { 536 r = -EIO; 537 goto failed_shutdown; 538 } 539 540 /* 541 * Fallback to more conservative semantics if setting cache 542 * options fails. Ignore errors from setting rbd_cache because the 543 * only possible error is that the option does not exist, and 544 * librbd defaults to no caching. If write through caching cannot 545 * be set up, fall back to no caching. 546 */ 547 if (flags & BDRV_O_NOCACHE) { 548 rados_conf_set(s->cluster, "rbd_cache", "false"); 549 } else { 550 rados_conf_set(s->cluster, "rbd_cache", "true"); 551 } 552 553 r = rados_connect(s->cluster); 554 if (r < 0) { 555 error_setg_errno(errp, -r, "error connecting"); 556 goto failed_shutdown; 557 } 558 559 r = rados_ioctx_create(s->cluster, pool, &s->io_ctx); 560 if (r < 0) { 561 error_setg_errno(errp, -r, "error opening pool %s", pool); 562 goto failed_shutdown; 563 } 564 565 r = rbd_open(s->io_ctx, s->name, &s->image, s->snap); 566 if (r < 0) { 567 error_setg_errno(errp, -r, "error reading header from %s", s->name); 568 goto failed_open; 569 } 570 571 bs->read_only = (s->snap != NULL); 572 573 qemu_opts_del(opts); 574 return 0; 575 576 failed_open: 577 rados_ioctx_destroy(s->io_ctx); 578 failed_shutdown: 579 rados_shutdown(s->cluster); 580 g_free(s->snap); 581 failed_opts: 582 qemu_opts_del(opts); 583 return r; 584 } 585 586 static void qemu_rbd_close(BlockDriverState *bs) 587 { 588 BDRVRBDState *s = bs->opaque; 589 590 rbd_close(s->image); 591 rados_ioctx_destroy(s->io_ctx); 592 g_free(s->snap); 593 rados_shutdown(s->cluster); 594 } 595 596 static const AIOCBInfo rbd_aiocb_info = { 597 .aiocb_size = sizeof(RBDAIOCB), 598 }; 599 600 static void rbd_finish_bh(void *opaque) 601 { 602 RADOSCB *rcb = opaque; 603 qemu_rbd_complete_aio(rcb); 604 } 605 606 /* 607 * This is the callback function for rbd_aio_read and _write 608 * 609 * Note: this function is being called from a non qemu thread so 610 * we need to be careful about what we do here. Generally we only 611 * schedule a BH, and do the rest of the io completion handling 612 * from rbd_finish_bh() which runs in a qemu context. 613 */ 614 static void rbd_finish_aiocb(rbd_completion_t c, RADOSCB *rcb) 615 { 616 RBDAIOCB *acb = rcb->acb; 617 618 rcb->ret = rbd_aio_get_return_value(c); 619 rbd_aio_release(c); 620 621 aio_bh_schedule_oneshot(bdrv_get_aio_context(acb->common.bs), 622 rbd_finish_bh, rcb); 623 } 624 625 static int rbd_aio_discard_wrapper(rbd_image_t image, 626 uint64_t off, 627 uint64_t len, 628 rbd_completion_t comp) 629 { 630 #ifdef LIBRBD_SUPPORTS_DISCARD 631 return rbd_aio_discard(image, off, len, comp); 632 #else 633 return -ENOTSUP; 634 #endif 635 } 636 637 static int rbd_aio_flush_wrapper(rbd_image_t image, 638 rbd_completion_t comp) 639 { 640 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH 641 return rbd_aio_flush(image, comp); 642 #else 643 return -ENOTSUP; 644 #endif 645 } 646 647 static BlockAIOCB *rbd_start_aio(BlockDriverState *bs, 648 int64_t off, 649 QEMUIOVector *qiov, 650 int64_t size, 651 BlockCompletionFunc *cb, 652 void *opaque, 653 RBDAIOCmd cmd) 654 { 655 RBDAIOCB *acb; 656 RADOSCB *rcb = NULL; 657 rbd_completion_t c; 658 char *buf; 659 int r; 660 661 BDRVRBDState *s = bs->opaque; 662 663 acb = qemu_aio_get(&rbd_aiocb_info, bs, cb, opaque); 664 acb->cmd = cmd; 665 acb->qiov = qiov; 666 assert(!qiov || qiov->size == size); 667 if (cmd == RBD_AIO_DISCARD || cmd == RBD_AIO_FLUSH) { 668 acb->bounce = NULL; 669 } else { 670 acb->bounce = qemu_try_blockalign(bs, qiov->size); 671 if (acb->bounce == NULL) { 672 goto failed; 673 } 674 } 675 acb->ret = 0; 676 acb->error = 0; 677 acb->s = s; 678 679 if (cmd == RBD_AIO_WRITE) { 680 qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size); 681 } 682 683 buf = acb->bounce; 684 685 rcb = g_new(RADOSCB, 1); 686 rcb->acb = acb; 687 rcb->buf = buf; 688 rcb->s = acb->s; 689 rcb->size = size; 690 r = rbd_aio_create_completion(rcb, (rbd_callback_t) rbd_finish_aiocb, &c); 691 if (r < 0) { 692 goto failed; 693 } 694 695 switch (cmd) { 696 case RBD_AIO_WRITE: 697 r = rbd_aio_write(s->image, off, size, buf, c); 698 break; 699 case RBD_AIO_READ: 700 r = rbd_aio_read(s->image, off, size, buf, c); 701 break; 702 case RBD_AIO_DISCARD: 703 r = rbd_aio_discard_wrapper(s->image, off, size, c); 704 break; 705 case RBD_AIO_FLUSH: 706 r = rbd_aio_flush_wrapper(s->image, c); 707 break; 708 default: 709 r = -EINVAL; 710 } 711 712 if (r < 0) { 713 goto failed_completion; 714 } 715 716 return &acb->common; 717 718 failed_completion: 719 rbd_aio_release(c); 720 failed: 721 g_free(rcb); 722 qemu_vfree(acb->bounce); 723 qemu_aio_unref(acb); 724 return NULL; 725 } 726 727 static BlockAIOCB *qemu_rbd_aio_readv(BlockDriverState *bs, 728 int64_t sector_num, 729 QEMUIOVector *qiov, 730 int nb_sectors, 731 BlockCompletionFunc *cb, 732 void *opaque) 733 { 734 return rbd_start_aio(bs, sector_num << BDRV_SECTOR_BITS, qiov, 735 (int64_t) nb_sectors << BDRV_SECTOR_BITS, cb, opaque, 736 RBD_AIO_READ); 737 } 738 739 static BlockAIOCB *qemu_rbd_aio_writev(BlockDriverState *bs, 740 int64_t sector_num, 741 QEMUIOVector *qiov, 742 int nb_sectors, 743 BlockCompletionFunc *cb, 744 void *opaque) 745 { 746 return rbd_start_aio(bs, sector_num << BDRV_SECTOR_BITS, qiov, 747 (int64_t) nb_sectors << BDRV_SECTOR_BITS, cb, opaque, 748 RBD_AIO_WRITE); 749 } 750 751 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH 752 static BlockAIOCB *qemu_rbd_aio_flush(BlockDriverState *bs, 753 BlockCompletionFunc *cb, 754 void *opaque) 755 { 756 return rbd_start_aio(bs, 0, NULL, 0, cb, opaque, RBD_AIO_FLUSH); 757 } 758 759 #else 760 761 static int qemu_rbd_co_flush(BlockDriverState *bs) 762 { 763 #if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 1) 764 /* rbd_flush added in 0.1.1 */ 765 BDRVRBDState *s = bs->opaque; 766 return rbd_flush(s->image); 767 #else 768 return 0; 769 #endif 770 } 771 #endif 772 773 static int qemu_rbd_getinfo(BlockDriverState *bs, BlockDriverInfo *bdi) 774 { 775 BDRVRBDState *s = bs->opaque; 776 rbd_image_info_t info; 777 int r; 778 779 r = rbd_stat(s->image, &info, sizeof(info)); 780 if (r < 0) { 781 return r; 782 } 783 784 bdi->cluster_size = info.obj_size; 785 return 0; 786 } 787 788 static int64_t qemu_rbd_getlength(BlockDriverState *bs) 789 { 790 BDRVRBDState *s = bs->opaque; 791 rbd_image_info_t info; 792 int r; 793 794 r = rbd_stat(s->image, &info, sizeof(info)); 795 if (r < 0) { 796 return r; 797 } 798 799 return info.size; 800 } 801 802 static int qemu_rbd_truncate(BlockDriverState *bs, int64_t offset) 803 { 804 BDRVRBDState *s = bs->opaque; 805 int r; 806 807 r = rbd_resize(s->image, offset); 808 if (r < 0) { 809 return r; 810 } 811 812 return 0; 813 } 814 815 static int qemu_rbd_snap_create(BlockDriverState *bs, 816 QEMUSnapshotInfo *sn_info) 817 { 818 BDRVRBDState *s = bs->opaque; 819 int r; 820 821 if (sn_info->name[0] == '\0') { 822 return -EINVAL; /* we need a name for rbd snapshots */ 823 } 824 825 /* 826 * rbd snapshots are using the name as the user controlled unique identifier 827 * we can't use the rbd snapid for that purpose, as it can't be set 828 */ 829 if (sn_info->id_str[0] != '\0' && 830 strcmp(sn_info->id_str, sn_info->name) != 0) { 831 return -EINVAL; 832 } 833 834 if (strlen(sn_info->name) >= sizeof(sn_info->id_str)) { 835 return -ERANGE; 836 } 837 838 r = rbd_snap_create(s->image, sn_info->name); 839 if (r < 0) { 840 error_report("failed to create snap: %s", strerror(-r)); 841 return r; 842 } 843 844 return 0; 845 } 846 847 static int qemu_rbd_snap_remove(BlockDriverState *bs, 848 const char *snapshot_id, 849 const char *snapshot_name, 850 Error **errp) 851 { 852 BDRVRBDState *s = bs->opaque; 853 int r; 854 855 if (!snapshot_name) { 856 error_setg(errp, "rbd need a valid snapshot name"); 857 return -EINVAL; 858 } 859 860 /* If snapshot_id is specified, it must be equal to name, see 861 qemu_rbd_snap_list() */ 862 if (snapshot_id && strcmp(snapshot_id, snapshot_name)) { 863 error_setg(errp, 864 "rbd do not support snapshot id, it should be NULL or " 865 "equal to snapshot name"); 866 return -EINVAL; 867 } 868 869 r = rbd_snap_remove(s->image, snapshot_name); 870 if (r < 0) { 871 error_setg_errno(errp, -r, "Failed to remove the snapshot"); 872 } 873 return r; 874 } 875 876 static int qemu_rbd_snap_rollback(BlockDriverState *bs, 877 const char *snapshot_name) 878 { 879 BDRVRBDState *s = bs->opaque; 880 881 return rbd_snap_rollback(s->image, snapshot_name); 882 } 883 884 static int qemu_rbd_snap_list(BlockDriverState *bs, 885 QEMUSnapshotInfo **psn_tab) 886 { 887 BDRVRBDState *s = bs->opaque; 888 QEMUSnapshotInfo *sn_info, *sn_tab = NULL; 889 int i, snap_count; 890 rbd_snap_info_t *snaps; 891 int max_snaps = RBD_MAX_SNAPS; 892 893 do { 894 snaps = g_new(rbd_snap_info_t, max_snaps); 895 snap_count = rbd_snap_list(s->image, snaps, &max_snaps); 896 if (snap_count <= 0) { 897 g_free(snaps); 898 } 899 } while (snap_count == -ERANGE); 900 901 if (snap_count <= 0) { 902 goto done; 903 } 904 905 sn_tab = g_new0(QEMUSnapshotInfo, snap_count); 906 907 for (i = 0; i < snap_count; i++) { 908 const char *snap_name = snaps[i].name; 909 910 sn_info = sn_tab + i; 911 pstrcpy(sn_info->id_str, sizeof(sn_info->id_str), snap_name); 912 pstrcpy(sn_info->name, sizeof(sn_info->name), snap_name); 913 914 sn_info->vm_state_size = snaps[i].size; 915 sn_info->date_sec = 0; 916 sn_info->date_nsec = 0; 917 sn_info->vm_clock_nsec = 0; 918 } 919 rbd_snap_list_end(snaps); 920 g_free(snaps); 921 922 done: 923 *psn_tab = sn_tab; 924 return snap_count; 925 } 926 927 #ifdef LIBRBD_SUPPORTS_DISCARD 928 static BlockAIOCB *qemu_rbd_aio_pdiscard(BlockDriverState *bs, 929 int64_t offset, 930 int count, 931 BlockCompletionFunc *cb, 932 void *opaque) 933 { 934 return rbd_start_aio(bs, offset, NULL, count, cb, opaque, 935 RBD_AIO_DISCARD); 936 } 937 #endif 938 939 #ifdef LIBRBD_SUPPORTS_INVALIDATE 940 static void qemu_rbd_invalidate_cache(BlockDriverState *bs, 941 Error **errp) 942 { 943 BDRVRBDState *s = bs->opaque; 944 int r = rbd_invalidate_cache(s->image); 945 if (r < 0) { 946 error_setg_errno(errp, -r, "Failed to invalidate the cache"); 947 } 948 } 949 #endif 950 951 static QemuOptsList qemu_rbd_create_opts = { 952 .name = "rbd-create-opts", 953 .head = QTAILQ_HEAD_INITIALIZER(qemu_rbd_create_opts.head), 954 .desc = { 955 { 956 .name = BLOCK_OPT_SIZE, 957 .type = QEMU_OPT_SIZE, 958 .help = "Virtual disk size" 959 }, 960 { 961 .name = BLOCK_OPT_CLUSTER_SIZE, 962 .type = QEMU_OPT_SIZE, 963 .help = "RBD object size" 964 }, 965 { 966 .name = "password-secret", 967 .type = QEMU_OPT_STRING, 968 .help = "ID of secret providing the password", 969 }, 970 { /* end of list */ } 971 } 972 }; 973 974 static BlockDriver bdrv_rbd = { 975 .format_name = "rbd", 976 .instance_size = sizeof(BDRVRBDState), 977 .bdrv_needs_filename = true, 978 .bdrv_file_open = qemu_rbd_open, 979 .bdrv_close = qemu_rbd_close, 980 .bdrv_create = qemu_rbd_create, 981 .bdrv_has_zero_init = bdrv_has_zero_init_1, 982 .bdrv_get_info = qemu_rbd_getinfo, 983 .create_opts = &qemu_rbd_create_opts, 984 .bdrv_getlength = qemu_rbd_getlength, 985 .bdrv_truncate = qemu_rbd_truncate, 986 .protocol_name = "rbd", 987 988 .bdrv_aio_readv = qemu_rbd_aio_readv, 989 .bdrv_aio_writev = qemu_rbd_aio_writev, 990 991 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH 992 .bdrv_aio_flush = qemu_rbd_aio_flush, 993 #else 994 .bdrv_co_flush_to_disk = qemu_rbd_co_flush, 995 #endif 996 997 #ifdef LIBRBD_SUPPORTS_DISCARD 998 .bdrv_aio_pdiscard = qemu_rbd_aio_pdiscard, 999 #endif 1000 1001 .bdrv_snapshot_create = qemu_rbd_snap_create, 1002 .bdrv_snapshot_delete = qemu_rbd_snap_remove, 1003 .bdrv_snapshot_list = qemu_rbd_snap_list, 1004 .bdrv_snapshot_goto = qemu_rbd_snap_rollback, 1005 #ifdef LIBRBD_SUPPORTS_INVALIDATE 1006 .bdrv_invalidate_cache = qemu_rbd_invalidate_cache, 1007 #endif 1008 }; 1009 1010 static void bdrv_rbd_init(void) 1011 { 1012 bdrv_register(&bdrv_rbd); 1013 } 1014 1015 block_init(bdrv_rbd_init); 1016