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 QEMUBH *bh; 75 int64_t ret; 76 QEMUIOVector *qiov; 77 char *bounce; 78 RBDAIOCmd cmd; 79 int error; 80 struct BDRVRBDState *s; 81 } RBDAIOCB; 82 83 typedef struct RADOSCB { 84 RBDAIOCB *acb; 85 struct BDRVRBDState *s; 86 int64_t size; 87 char *buf; 88 int64_t ret; 89 } RADOSCB; 90 91 typedef struct BDRVRBDState { 92 rados_t cluster; 93 rados_ioctx_t io_ctx; 94 rbd_image_t image; 95 char name[RBD_MAX_IMAGE_NAME_SIZE]; 96 char *snap; 97 } BDRVRBDState; 98 99 static int qemu_rbd_next_tok(char *dst, int dst_len, 100 char *src, char delim, 101 const char *name, 102 char **p, Error **errp) 103 { 104 int l; 105 char *end; 106 107 *p = NULL; 108 109 if (delim != '\0') { 110 for (end = src; *end; ++end) { 111 if (*end == delim) { 112 break; 113 } 114 if (*end == '\\' && end[1] != '\0') { 115 end++; 116 } 117 } 118 if (*end == delim) { 119 *p = end + 1; 120 *end = '\0'; 121 } 122 } 123 l = strlen(src); 124 if (l >= dst_len) { 125 error_setg(errp, "%s too long", name); 126 return -EINVAL; 127 } else if (l == 0) { 128 error_setg(errp, "%s too short", name); 129 return -EINVAL; 130 } 131 132 pstrcpy(dst, dst_len, src); 133 134 return 0; 135 } 136 137 static void qemu_rbd_unescape(char *src) 138 { 139 char *p; 140 141 for (p = src; *src; ++src, ++p) { 142 if (*src == '\\' && src[1] != '\0') { 143 src++; 144 } 145 *p = *src; 146 } 147 *p = '\0'; 148 } 149 150 static int qemu_rbd_parsename(const char *filename, 151 char *pool, int pool_len, 152 char *snap, int snap_len, 153 char *name, int name_len, 154 char *conf, int conf_len, 155 Error **errp) 156 { 157 const char *start; 158 char *p, *buf; 159 int ret; 160 161 if (!strstart(filename, "rbd:", &start)) { 162 error_setg(errp, "File name must start with 'rbd:'"); 163 return -EINVAL; 164 } 165 166 buf = g_strdup(start); 167 p = buf; 168 *snap = '\0'; 169 *conf = '\0'; 170 171 ret = qemu_rbd_next_tok(pool, pool_len, p, 172 '/', "pool name", &p, errp); 173 if (ret < 0 || !p) { 174 ret = -EINVAL; 175 goto done; 176 } 177 qemu_rbd_unescape(pool); 178 179 if (strchr(p, '@')) { 180 ret = qemu_rbd_next_tok(name, name_len, p, 181 '@', "object name", &p, errp); 182 if (ret < 0) { 183 goto done; 184 } 185 ret = qemu_rbd_next_tok(snap, snap_len, p, 186 ':', "snap name", &p, errp); 187 qemu_rbd_unescape(snap); 188 } else { 189 ret = qemu_rbd_next_tok(name, name_len, p, 190 ':', "object name", &p, errp); 191 } 192 qemu_rbd_unescape(name); 193 if (ret < 0 || !p) { 194 goto done; 195 } 196 197 ret = qemu_rbd_next_tok(conf, conf_len, p, 198 '\0', "configuration", &p, errp); 199 200 done: 201 g_free(buf); 202 return ret; 203 } 204 205 static char *qemu_rbd_parse_clientname(const char *conf, char *clientname) 206 { 207 const char *p = conf; 208 209 while (*p) { 210 int len; 211 const char *end = strchr(p, ':'); 212 213 if (end) { 214 len = end - p; 215 } else { 216 len = strlen(p); 217 } 218 219 if (strncmp(p, "id=", 3) == 0) { 220 len -= 3; 221 strncpy(clientname, p + 3, len); 222 clientname[len] = '\0'; 223 return clientname; 224 } 225 if (end == NULL) { 226 break; 227 } 228 p = end + 1; 229 } 230 return NULL; 231 } 232 233 234 static int qemu_rbd_set_auth(rados_t cluster, const char *secretid, 235 Error **errp) 236 { 237 if (secretid == 0) { 238 return 0; 239 } 240 241 gchar *secret = qcrypto_secret_lookup_as_base64(secretid, 242 errp); 243 if (!secret) { 244 return -1; 245 } 246 247 rados_conf_set(cluster, "key", secret); 248 g_free(secret); 249 250 return 0; 251 } 252 253 254 static int qemu_rbd_set_conf(rados_t cluster, const char *conf, 255 bool only_read_conf_file, 256 Error **errp) 257 { 258 char *p, *buf; 259 char name[RBD_MAX_CONF_NAME_SIZE]; 260 char value[RBD_MAX_CONF_VAL_SIZE]; 261 int ret = 0; 262 263 buf = g_strdup(conf); 264 p = buf; 265 266 while (p) { 267 ret = qemu_rbd_next_tok(name, sizeof(name), p, 268 '=', "conf option name", &p, errp); 269 if (ret < 0) { 270 break; 271 } 272 qemu_rbd_unescape(name); 273 274 if (!p) { 275 error_setg(errp, "conf option %s has no value", name); 276 ret = -EINVAL; 277 break; 278 } 279 280 ret = qemu_rbd_next_tok(value, sizeof(value), p, 281 ':', "conf option value", &p, errp); 282 if (ret < 0) { 283 break; 284 } 285 qemu_rbd_unescape(value); 286 287 if (strcmp(name, "conf") == 0) { 288 /* read the conf file alone, so it doesn't override more 289 specific settings for a particular device */ 290 if (only_read_conf_file) { 291 ret = rados_conf_read_file(cluster, value); 292 if (ret < 0) { 293 error_setg(errp, "error reading conf file %s", 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(errp, "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 if (rados_create(&cluster, clientname) < 0) { 358 error_setg(errp, "error initializing"); 359 return -EIO; 360 } 361 362 if (strstr(conf, "conf=") == NULL) { 363 /* try default location, but ignore failure */ 364 rados_conf_read_file(cluster, NULL); 365 } else if (conf[0] != '\0' && 366 qemu_rbd_set_conf(cluster, conf, true, &local_err) < 0) { 367 rados_shutdown(cluster); 368 error_propagate(errp, local_err); 369 return -EIO; 370 } 371 372 if (conf[0] != '\0' && 373 qemu_rbd_set_conf(cluster, conf, false, &local_err) < 0) { 374 rados_shutdown(cluster); 375 error_propagate(errp, local_err); 376 return -EIO; 377 } 378 379 if (qemu_rbd_set_auth(cluster, secretid, errp) < 0) { 380 rados_shutdown(cluster); 381 return -EIO; 382 } 383 384 if (rados_connect(cluster) < 0) { 385 error_setg(errp, "error connecting"); 386 rados_shutdown(cluster); 387 return -EIO; 388 } 389 390 if (rados_ioctx_create(cluster, pool, &io_ctx) < 0) { 391 error_setg(errp, "error opening pool %s", pool); 392 rados_shutdown(cluster); 393 return -EIO; 394 } 395 396 ret = rbd_create(io_ctx, name, bytes, &obj_order); 397 rados_ioctx_destroy(io_ctx); 398 rados_shutdown(cluster); 399 400 return ret; 401 } 402 403 /* 404 * This aio completion is being called from rbd_finish_bh() and runs in qemu 405 * BH context. 406 */ 407 static void qemu_rbd_complete_aio(RADOSCB *rcb) 408 { 409 RBDAIOCB *acb = rcb->acb; 410 int64_t r; 411 412 r = rcb->ret; 413 414 if (acb->cmd != RBD_AIO_READ) { 415 if (r < 0) { 416 acb->ret = r; 417 acb->error = 1; 418 } else if (!acb->error) { 419 acb->ret = rcb->size; 420 } 421 } else { 422 if (r < 0) { 423 memset(rcb->buf, 0, rcb->size); 424 acb->ret = r; 425 acb->error = 1; 426 } else if (r < rcb->size) { 427 memset(rcb->buf + r, 0, rcb->size - r); 428 if (!acb->error) { 429 acb->ret = rcb->size; 430 } 431 } else if (!acb->error) { 432 acb->ret = r; 433 } 434 } 435 436 g_free(rcb); 437 438 if (acb->cmd == RBD_AIO_READ) { 439 qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size); 440 } 441 qemu_vfree(acb->bounce); 442 acb->common.cb(acb->common.opaque, (acb->ret > 0 ? 0 : acb->ret)); 443 444 qemu_aio_unref(acb); 445 } 446 447 /* TODO Convert to fine grained options */ 448 static QemuOptsList runtime_opts = { 449 .name = "rbd", 450 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 451 .desc = { 452 { 453 .name = "filename", 454 .type = QEMU_OPT_STRING, 455 .help = "Specification of the rbd image", 456 }, 457 { 458 .name = "password-secret", 459 .type = QEMU_OPT_STRING, 460 .help = "ID of secret providing the password", 461 }, 462 { /* end of list */ } 463 }, 464 }; 465 466 static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags, 467 Error **errp) 468 { 469 BDRVRBDState *s = bs->opaque; 470 char pool[RBD_MAX_POOL_NAME_SIZE]; 471 char snap_buf[RBD_MAX_SNAP_NAME_SIZE]; 472 char conf[RBD_MAX_CONF_SIZE]; 473 char clientname_buf[RBD_MAX_CONF_SIZE]; 474 char *clientname; 475 const char *secretid; 476 QemuOpts *opts; 477 Error *local_err = NULL; 478 const char *filename; 479 int r; 480 481 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 482 qemu_opts_absorb_qdict(opts, options, &local_err); 483 if (local_err) { 484 error_propagate(errp, local_err); 485 qemu_opts_del(opts); 486 return -EINVAL; 487 } 488 489 filename = qemu_opt_get(opts, "filename"); 490 secretid = qemu_opt_get(opts, "password-secret"); 491 492 if (qemu_rbd_parsename(filename, pool, sizeof(pool), 493 snap_buf, sizeof(snap_buf), 494 s->name, sizeof(s->name), 495 conf, sizeof(conf), errp) < 0) { 496 r = -EINVAL; 497 goto failed_opts; 498 } 499 500 clientname = qemu_rbd_parse_clientname(conf, clientname_buf); 501 r = rados_create(&s->cluster, clientname); 502 if (r < 0) { 503 error_setg(errp, "error initializing"); 504 goto failed_opts; 505 } 506 507 s->snap = NULL; 508 if (snap_buf[0] != '\0') { 509 s->snap = g_strdup(snap_buf); 510 } 511 512 if (strstr(conf, "conf=") == NULL) { 513 /* try default location, but ignore failure */ 514 rados_conf_read_file(s->cluster, NULL); 515 } else if (conf[0] != '\0') { 516 r = qemu_rbd_set_conf(s->cluster, conf, true, errp); 517 if (r < 0) { 518 goto failed_shutdown; 519 } 520 } 521 522 if (conf[0] != '\0') { 523 r = qemu_rbd_set_conf(s->cluster, conf, false, errp); 524 if (r < 0) { 525 goto failed_shutdown; 526 } 527 } 528 529 if (qemu_rbd_set_auth(s->cluster, secretid, errp) < 0) { 530 r = -EIO; 531 goto failed_shutdown; 532 } 533 534 /* 535 * Fallback to more conservative semantics if setting cache 536 * options fails. Ignore errors from setting rbd_cache because the 537 * only possible error is that the option does not exist, and 538 * librbd defaults to no caching. If write through caching cannot 539 * be set up, fall back to no caching. 540 */ 541 if (flags & BDRV_O_NOCACHE) { 542 rados_conf_set(s->cluster, "rbd_cache", "false"); 543 } else { 544 rados_conf_set(s->cluster, "rbd_cache", "true"); 545 } 546 547 r = rados_connect(s->cluster); 548 if (r < 0) { 549 error_setg(errp, "error connecting"); 550 goto failed_shutdown; 551 } 552 553 r = rados_ioctx_create(s->cluster, pool, &s->io_ctx); 554 if (r < 0) { 555 error_setg(errp, "error opening pool %s", pool); 556 goto failed_shutdown; 557 } 558 559 r = rbd_open(s->io_ctx, s->name, &s->image, s->snap); 560 if (r < 0) { 561 error_setg(errp, "error reading header from %s", s->name); 562 goto failed_open; 563 } 564 565 bs->read_only = (s->snap != NULL); 566 567 qemu_opts_del(opts); 568 return 0; 569 570 failed_open: 571 rados_ioctx_destroy(s->io_ctx); 572 failed_shutdown: 573 rados_shutdown(s->cluster); 574 g_free(s->snap); 575 failed_opts: 576 qemu_opts_del(opts); 577 return r; 578 } 579 580 static void qemu_rbd_close(BlockDriverState *bs) 581 { 582 BDRVRBDState *s = bs->opaque; 583 584 rbd_close(s->image); 585 rados_ioctx_destroy(s->io_ctx); 586 g_free(s->snap); 587 rados_shutdown(s->cluster); 588 } 589 590 static const AIOCBInfo rbd_aiocb_info = { 591 .aiocb_size = sizeof(RBDAIOCB), 592 }; 593 594 static void rbd_finish_bh(void *opaque) 595 { 596 RADOSCB *rcb = opaque; 597 qemu_bh_delete(rcb->acb->bh); 598 qemu_rbd_complete_aio(rcb); 599 } 600 601 /* 602 * This is the callback function for rbd_aio_read and _write 603 * 604 * Note: this function is being called from a non qemu thread so 605 * we need to be careful about what we do here. Generally we only 606 * schedule a BH, and do the rest of the io completion handling 607 * from rbd_finish_bh() which runs in a qemu context. 608 */ 609 static void rbd_finish_aiocb(rbd_completion_t c, RADOSCB *rcb) 610 { 611 RBDAIOCB *acb = rcb->acb; 612 613 rcb->ret = rbd_aio_get_return_value(c); 614 rbd_aio_release(c); 615 616 acb->bh = aio_bh_new(bdrv_get_aio_context(acb->common.bs), 617 rbd_finish_bh, rcb); 618 qemu_bh_schedule(acb->bh); 619 } 620 621 static int rbd_aio_discard_wrapper(rbd_image_t image, 622 uint64_t off, 623 uint64_t len, 624 rbd_completion_t comp) 625 { 626 #ifdef LIBRBD_SUPPORTS_DISCARD 627 return rbd_aio_discard(image, off, len, comp); 628 #else 629 return -ENOTSUP; 630 #endif 631 } 632 633 static int rbd_aio_flush_wrapper(rbd_image_t image, 634 rbd_completion_t comp) 635 { 636 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH 637 return rbd_aio_flush(image, comp); 638 #else 639 return -ENOTSUP; 640 #endif 641 } 642 643 static BlockAIOCB *rbd_start_aio(BlockDriverState *bs, 644 int64_t sector_num, 645 QEMUIOVector *qiov, 646 int nb_sectors, 647 BlockCompletionFunc *cb, 648 void *opaque, 649 RBDAIOCmd cmd) 650 { 651 RBDAIOCB *acb; 652 RADOSCB *rcb = NULL; 653 rbd_completion_t c; 654 int64_t off, size; 655 char *buf; 656 int r; 657 658 BDRVRBDState *s = bs->opaque; 659 660 acb = qemu_aio_get(&rbd_aiocb_info, bs, cb, opaque); 661 acb->cmd = cmd; 662 acb->qiov = qiov; 663 if (cmd == RBD_AIO_DISCARD || cmd == RBD_AIO_FLUSH) { 664 acb->bounce = NULL; 665 } else { 666 acb->bounce = qemu_try_blockalign(bs, qiov->size); 667 if (acb->bounce == NULL) { 668 goto failed; 669 } 670 } 671 acb->ret = 0; 672 acb->error = 0; 673 acb->s = s; 674 acb->bh = NULL; 675 676 if (cmd == RBD_AIO_WRITE) { 677 qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size); 678 } 679 680 buf = acb->bounce; 681 682 off = sector_num * BDRV_SECTOR_SIZE; 683 size = nb_sectors * BDRV_SECTOR_SIZE; 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, qiov, nb_sectors, cb, opaque, 735 RBD_AIO_READ); 736 } 737 738 static BlockAIOCB *qemu_rbd_aio_writev(BlockDriverState *bs, 739 int64_t sector_num, 740 QEMUIOVector *qiov, 741 int nb_sectors, 742 BlockCompletionFunc *cb, 743 void *opaque) 744 { 745 return rbd_start_aio(bs, sector_num, qiov, nb_sectors, cb, opaque, 746 RBD_AIO_WRITE); 747 } 748 749 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH 750 static BlockAIOCB *qemu_rbd_aio_flush(BlockDriverState *bs, 751 BlockCompletionFunc *cb, 752 void *opaque) 753 { 754 return rbd_start_aio(bs, 0, NULL, 0, cb, opaque, RBD_AIO_FLUSH); 755 } 756 757 #else 758 759 static int qemu_rbd_co_flush(BlockDriverState *bs) 760 { 761 #if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 1) 762 /* rbd_flush added in 0.1.1 */ 763 BDRVRBDState *s = bs->opaque; 764 return rbd_flush(s->image); 765 #else 766 return 0; 767 #endif 768 } 769 #endif 770 771 static int qemu_rbd_getinfo(BlockDriverState *bs, BlockDriverInfo *bdi) 772 { 773 BDRVRBDState *s = bs->opaque; 774 rbd_image_info_t info; 775 int r; 776 777 r = rbd_stat(s->image, &info, sizeof(info)); 778 if (r < 0) { 779 return r; 780 } 781 782 bdi->cluster_size = info.obj_size; 783 return 0; 784 } 785 786 static int64_t qemu_rbd_getlength(BlockDriverState *bs) 787 { 788 BDRVRBDState *s = bs->opaque; 789 rbd_image_info_t info; 790 int r; 791 792 r = rbd_stat(s->image, &info, sizeof(info)); 793 if (r < 0) { 794 return r; 795 } 796 797 return info.size; 798 } 799 800 static int qemu_rbd_truncate(BlockDriverState *bs, int64_t offset) 801 { 802 BDRVRBDState *s = bs->opaque; 803 int r; 804 805 r = rbd_resize(s->image, offset); 806 if (r < 0) { 807 return r; 808 } 809 810 return 0; 811 } 812 813 static int qemu_rbd_snap_create(BlockDriverState *bs, 814 QEMUSnapshotInfo *sn_info) 815 { 816 BDRVRBDState *s = bs->opaque; 817 int r; 818 819 if (sn_info->name[0] == '\0') { 820 return -EINVAL; /* we need a name for rbd snapshots */ 821 } 822 823 /* 824 * rbd snapshots are using the name as the user controlled unique identifier 825 * we can't use the rbd snapid for that purpose, as it can't be set 826 */ 827 if (sn_info->id_str[0] != '\0' && 828 strcmp(sn_info->id_str, sn_info->name) != 0) { 829 return -EINVAL; 830 } 831 832 if (strlen(sn_info->name) >= sizeof(sn_info->id_str)) { 833 return -ERANGE; 834 } 835 836 r = rbd_snap_create(s->image, sn_info->name); 837 if (r < 0) { 838 error_report("failed to create snap: %s", strerror(-r)); 839 return r; 840 } 841 842 return 0; 843 } 844 845 static int qemu_rbd_snap_remove(BlockDriverState *bs, 846 const char *snapshot_id, 847 const char *snapshot_name, 848 Error **errp) 849 { 850 BDRVRBDState *s = bs->opaque; 851 int r; 852 853 if (!snapshot_name) { 854 error_setg(errp, "rbd need a valid snapshot name"); 855 return -EINVAL; 856 } 857 858 /* If snapshot_id is specified, it must be equal to name, see 859 qemu_rbd_snap_list() */ 860 if (snapshot_id && strcmp(snapshot_id, snapshot_name)) { 861 error_setg(errp, 862 "rbd do not support snapshot id, it should be NULL or " 863 "equal to snapshot name"); 864 return -EINVAL; 865 } 866 867 r = rbd_snap_remove(s->image, snapshot_name); 868 if (r < 0) { 869 error_setg_errno(errp, -r, "Failed to remove the snapshot"); 870 } 871 return r; 872 } 873 874 static int qemu_rbd_snap_rollback(BlockDriverState *bs, 875 const char *snapshot_name) 876 { 877 BDRVRBDState *s = bs->opaque; 878 int r; 879 880 r = rbd_snap_rollback(s->image, snapshot_name); 881 return r; 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_discard(BlockDriverState *bs, 929 int64_t sector_num, 930 int nb_sectors, 931 BlockCompletionFunc *cb, 932 void *opaque) 933 { 934 return rbd_start_aio(bs, sector_num, NULL, nb_sectors, 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_discard = qemu_rbd_aio_discard, 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