1 /* 2 rbd.c -- Export ceph rados objects as a Linux block device 3 4 5 based on drivers/block/osdblk.c: 6 7 Copyright 2009 Red Hat, Inc. 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; see the file COPYING. If not, write to 20 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 21 22 23 24 For usage instructions, please refer to: 25 26 Documentation/ABI/testing/sysfs-bus-rbd 27 28 */ 29 30 #include <linux/ceph/libceph.h> 31 #include <linux/ceph/osd_client.h> 32 #include <linux/ceph/mon_client.h> 33 #include <linux/ceph/decode.h> 34 #include <linux/parser.h> 35 36 #include <linux/kernel.h> 37 #include <linux/device.h> 38 #include <linux/module.h> 39 #include <linux/fs.h> 40 #include <linux/blkdev.h> 41 42 #include "rbd_types.h" 43 44 #define DRV_NAME "rbd" 45 #define DRV_NAME_LONG "rbd (rados block device)" 46 47 #define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */ 48 49 #define RBD_MAX_MD_NAME_LEN (96 + sizeof(RBD_SUFFIX)) 50 #define RBD_MAX_POOL_NAME_LEN 64 51 #define RBD_MAX_SNAP_NAME_LEN 32 52 #define RBD_MAX_OPT_LEN 1024 53 54 #define RBD_SNAP_HEAD_NAME "-" 55 56 #define DEV_NAME_LEN 32 57 58 #define RBD_NOTIFY_TIMEOUT_DEFAULT 10 59 60 /* 61 * block device image metadata (in-memory version) 62 */ 63 struct rbd_image_header { 64 u64 image_size; 65 char block_name[32]; 66 __u8 obj_order; 67 __u8 crypt_type; 68 __u8 comp_type; 69 struct rw_semaphore snap_rwsem; 70 struct ceph_snap_context *snapc; 71 size_t snap_names_len; 72 u64 snap_seq; 73 u32 total_snaps; 74 75 char *snap_names; 76 u64 *snap_sizes; 77 78 u64 obj_version; 79 }; 80 81 struct rbd_options { 82 int notify_timeout; 83 }; 84 85 /* 86 * an instance of the client. multiple devices may share a client. 87 */ 88 struct rbd_client { 89 struct ceph_client *client; 90 struct rbd_options *rbd_opts; 91 struct kref kref; 92 struct list_head node; 93 }; 94 95 struct rbd_req_coll; 96 97 /* 98 * a single io request 99 */ 100 struct rbd_request { 101 struct request *rq; /* blk layer request */ 102 struct bio *bio; /* cloned bio */ 103 struct page **pages; /* list of used pages */ 104 u64 len; 105 int coll_index; 106 struct rbd_req_coll *coll; 107 }; 108 109 struct rbd_req_status { 110 int done; 111 int rc; 112 u64 bytes; 113 }; 114 115 /* 116 * a collection of requests 117 */ 118 struct rbd_req_coll { 119 int total; 120 int num_done; 121 struct kref kref; 122 struct rbd_req_status status[0]; 123 }; 124 125 struct rbd_snap { 126 struct device dev; 127 const char *name; 128 size_t size; 129 struct list_head node; 130 u64 id; 131 }; 132 133 /* 134 * a single device 135 */ 136 struct rbd_device { 137 int id; /* blkdev unique id */ 138 139 int major; /* blkdev assigned major */ 140 struct gendisk *disk; /* blkdev's gendisk and rq */ 141 struct request_queue *q; 142 143 struct ceph_client *client; 144 struct rbd_client *rbd_client; 145 146 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */ 147 148 spinlock_t lock; /* queue lock */ 149 150 struct rbd_image_header header; 151 char obj[RBD_MAX_OBJ_NAME_LEN]; /* rbd image name */ 152 int obj_len; 153 char obj_md_name[RBD_MAX_MD_NAME_LEN]; /* hdr nm. */ 154 char pool_name[RBD_MAX_POOL_NAME_LEN]; 155 int poolid; 156 157 struct ceph_osd_event *watch_event; 158 struct ceph_osd_request *watch_request; 159 160 char snap_name[RBD_MAX_SNAP_NAME_LEN]; 161 u32 cur_snap; /* index+1 of current snapshot within snap context 162 0 - for the head */ 163 int read_only; 164 165 struct list_head node; 166 167 /* list of snapshots */ 168 struct list_head snaps; 169 170 /* sysfs related */ 171 struct device dev; 172 }; 173 174 static struct bus_type rbd_bus_type = { 175 .name = "rbd", 176 }; 177 178 static spinlock_t node_lock; /* protects client get/put */ 179 180 static DEFINE_MUTEX(ctl_mutex); /* Serialize open/close/setup/teardown */ 181 static LIST_HEAD(rbd_dev_list); /* devices */ 182 static LIST_HEAD(rbd_client_list); /* clients */ 183 184 static int __rbd_init_snaps_header(struct rbd_device *rbd_dev); 185 static void rbd_dev_release(struct device *dev); 186 static ssize_t rbd_snap_rollback(struct device *dev, 187 struct device_attribute *attr, 188 const char *buf, 189 size_t size); 190 static ssize_t rbd_snap_add(struct device *dev, 191 struct device_attribute *attr, 192 const char *buf, 193 size_t count); 194 static void __rbd_remove_snap_dev(struct rbd_device *rbd_dev, 195 struct rbd_snap *snap);; 196 197 198 static struct rbd_device *dev_to_rbd(struct device *dev) 199 { 200 return container_of(dev, struct rbd_device, dev); 201 } 202 203 static struct device *rbd_get_dev(struct rbd_device *rbd_dev) 204 { 205 return get_device(&rbd_dev->dev); 206 } 207 208 static void rbd_put_dev(struct rbd_device *rbd_dev) 209 { 210 put_device(&rbd_dev->dev); 211 } 212 213 static int __rbd_update_snaps(struct rbd_device *rbd_dev); 214 215 static int rbd_open(struct block_device *bdev, fmode_t mode) 216 { 217 struct gendisk *disk = bdev->bd_disk; 218 struct rbd_device *rbd_dev = disk->private_data; 219 220 rbd_get_dev(rbd_dev); 221 222 set_device_ro(bdev, rbd_dev->read_only); 223 224 if ((mode & FMODE_WRITE) && rbd_dev->read_only) 225 return -EROFS; 226 227 return 0; 228 } 229 230 static int rbd_release(struct gendisk *disk, fmode_t mode) 231 { 232 struct rbd_device *rbd_dev = disk->private_data; 233 234 rbd_put_dev(rbd_dev); 235 236 return 0; 237 } 238 239 static const struct block_device_operations rbd_bd_ops = { 240 .owner = THIS_MODULE, 241 .open = rbd_open, 242 .release = rbd_release, 243 }; 244 245 /* 246 * Initialize an rbd client instance. 247 * We own *opt. 248 */ 249 static struct rbd_client *rbd_client_create(struct ceph_options *opt, 250 struct rbd_options *rbd_opts) 251 { 252 struct rbd_client *rbdc; 253 int ret = -ENOMEM; 254 255 dout("rbd_client_create\n"); 256 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL); 257 if (!rbdc) 258 goto out_opt; 259 260 kref_init(&rbdc->kref); 261 INIT_LIST_HEAD(&rbdc->node); 262 263 rbdc->client = ceph_create_client(opt, rbdc); 264 if (IS_ERR(rbdc->client)) 265 goto out_rbdc; 266 opt = NULL; /* Now rbdc->client is responsible for opt */ 267 268 ret = ceph_open_session(rbdc->client); 269 if (ret < 0) 270 goto out_err; 271 272 rbdc->rbd_opts = rbd_opts; 273 274 spin_lock(&node_lock); 275 list_add_tail(&rbdc->node, &rbd_client_list); 276 spin_unlock(&node_lock); 277 278 dout("rbd_client_create created %p\n", rbdc); 279 return rbdc; 280 281 out_err: 282 ceph_destroy_client(rbdc->client); 283 out_rbdc: 284 kfree(rbdc); 285 out_opt: 286 if (opt) 287 ceph_destroy_options(opt); 288 return ERR_PTR(ret); 289 } 290 291 /* 292 * Find a ceph client with specific addr and configuration. 293 */ 294 static struct rbd_client *__rbd_client_find(struct ceph_options *opt) 295 { 296 struct rbd_client *client_node; 297 298 if (opt->flags & CEPH_OPT_NOSHARE) 299 return NULL; 300 301 list_for_each_entry(client_node, &rbd_client_list, node) 302 if (ceph_compare_options(opt, client_node->client) == 0) 303 return client_node; 304 return NULL; 305 } 306 307 /* 308 * mount options 309 */ 310 enum { 311 Opt_notify_timeout, 312 Opt_last_int, 313 /* int args above */ 314 Opt_last_string, 315 /* string args above */ 316 }; 317 318 static match_table_t rbdopt_tokens = { 319 {Opt_notify_timeout, "notify_timeout=%d"}, 320 /* int args above */ 321 /* string args above */ 322 {-1, NULL} 323 }; 324 325 static int parse_rbd_opts_token(char *c, void *private) 326 { 327 struct rbd_options *rbdopt = private; 328 substring_t argstr[MAX_OPT_ARGS]; 329 int token, intval, ret; 330 331 token = match_token((char *)c, rbdopt_tokens, argstr); 332 if (token < 0) 333 return -EINVAL; 334 335 if (token < Opt_last_int) { 336 ret = match_int(&argstr[0], &intval); 337 if (ret < 0) { 338 pr_err("bad mount option arg (not int) " 339 "at '%s'\n", c); 340 return ret; 341 } 342 dout("got int token %d val %d\n", token, intval); 343 } else if (token > Opt_last_int && token < Opt_last_string) { 344 dout("got string token %d val %s\n", token, 345 argstr[0].from); 346 } else { 347 dout("got token %d\n", token); 348 } 349 350 switch (token) { 351 case Opt_notify_timeout: 352 rbdopt->notify_timeout = intval; 353 break; 354 default: 355 BUG_ON(token); 356 } 357 return 0; 358 } 359 360 /* 361 * Get a ceph client with specific addr and configuration, if one does 362 * not exist create it. 363 */ 364 static int rbd_get_client(struct rbd_device *rbd_dev, const char *mon_addr, 365 char *options) 366 { 367 struct rbd_client *rbdc; 368 struct ceph_options *opt; 369 int ret; 370 struct rbd_options *rbd_opts; 371 372 rbd_opts = kzalloc(sizeof(*rbd_opts), GFP_KERNEL); 373 if (!rbd_opts) 374 return -ENOMEM; 375 376 rbd_opts->notify_timeout = RBD_NOTIFY_TIMEOUT_DEFAULT; 377 378 ret = ceph_parse_options(&opt, options, mon_addr, 379 mon_addr + strlen(mon_addr), parse_rbd_opts_token, rbd_opts); 380 if (ret < 0) 381 goto done_err; 382 383 spin_lock(&node_lock); 384 rbdc = __rbd_client_find(opt); 385 if (rbdc) { 386 ceph_destroy_options(opt); 387 388 /* using an existing client */ 389 kref_get(&rbdc->kref); 390 rbd_dev->rbd_client = rbdc; 391 rbd_dev->client = rbdc->client; 392 spin_unlock(&node_lock); 393 return 0; 394 } 395 spin_unlock(&node_lock); 396 397 rbdc = rbd_client_create(opt, rbd_opts); 398 if (IS_ERR(rbdc)) { 399 ret = PTR_ERR(rbdc); 400 goto done_err; 401 } 402 403 rbd_dev->rbd_client = rbdc; 404 rbd_dev->client = rbdc->client; 405 return 0; 406 done_err: 407 kfree(rbd_opts); 408 return ret; 409 } 410 411 /* 412 * Destroy ceph client 413 */ 414 static void rbd_client_release(struct kref *kref) 415 { 416 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref); 417 418 dout("rbd_release_client %p\n", rbdc); 419 spin_lock(&node_lock); 420 list_del(&rbdc->node); 421 spin_unlock(&node_lock); 422 423 ceph_destroy_client(rbdc->client); 424 kfree(rbdc->rbd_opts); 425 kfree(rbdc); 426 } 427 428 /* 429 * Drop reference to ceph client node. If it's not referenced anymore, release 430 * it. 431 */ 432 static void rbd_put_client(struct rbd_device *rbd_dev) 433 { 434 kref_put(&rbd_dev->rbd_client->kref, rbd_client_release); 435 rbd_dev->rbd_client = NULL; 436 rbd_dev->client = NULL; 437 } 438 439 /* 440 * Destroy requests collection 441 */ 442 static void rbd_coll_release(struct kref *kref) 443 { 444 struct rbd_req_coll *coll = 445 container_of(kref, struct rbd_req_coll, kref); 446 447 dout("rbd_coll_release %p\n", coll); 448 kfree(coll); 449 } 450 451 /* 452 * Create a new header structure, translate header format from the on-disk 453 * header. 454 */ 455 static int rbd_header_from_disk(struct rbd_image_header *header, 456 struct rbd_image_header_ondisk *ondisk, 457 int allocated_snaps, 458 gfp_t gfp_flags) 459 { 460 int i; 461 u32 snap_count = le32_to_cpu(ondisk->snap_count); 462 int ret = -ENOMEM; 463 464 init_rwsem(&header->snap_rwsem); 465 header->snap_names_len = le64_to_cpu(ondisk->snap_names_len); 466 header->snapc = kmalloc(sizeof(struct ceph_snap_context) + 467 snap_count * 468 sizeof(struct rbd_image_snap_ondisk), 469 gfp_flags); 470 if (!header->snapc) 471 return -ENOMEM; 472 if (snap_count) { 473 header->snap_names = kmalloc(header->snap_names_len, 474 GFP_KERNEL); 475 if (!header->snap_names) 476 goto err_snapc; 477 header->snap_sizes = kmalloc(snap_count * sizeof(u64), 478 GFP_KERNEL); 479 if (!header->snap_sizes) 480 goto err_names; 481 } else { 482 header->snap_names = NULL; 483 header->snap_sizes = NULL; 484 } 485 memcpy(header->block_name, ondisk->block_name, 486 sizeof(ondisk->block_name)); 487 488 header->image_size = le64_to_cpu(ondisk->image_size); 489 header->obj_order = ondisk->options.order; 490 header->crypt_type = ondisk->options.crypt_type; 491 header->comp_type = ondisk->options.comp_type; 492 493 atomic_set(&header->snapc->nref, 1); 494 header->snap_seq = le64_to_cpu(ondisk->snap_seq); 495 header->snapc->num_snaps = snap_count; 496 header->total_snaps = snap_count; 497 498 if (snap_count && 499 allocated_snaps == snap_count) { 500 for (i = 0; i < snap_count; i++) { 501 header->snapc->snaps[i] = 502 le64_to_cpu(ondisk->snaps[i].id); 503 header->snap_sizes[i] = 504 le64_to_cpu(ondisk->snaps[i].image_size); 505 } 506 507 /* copy snapshot names */ 508 memcpy(header->snap_names, &ondisk->snaps[i], 509 header->snap_names_len); 510 } 511 512 return 0; 513 514 err_names: 515 kfree(header->snap_names); 516 err_snapc: 517 kfree(header->snapc); 518 return ret; 519 } 520 521 static int snap_index(struct rbd_image_header *header, int snap_num) 522 { 523 return header->total_snaps - snap_num; 524 } 525 526 static u64 cur_snap_id(struct rbd_device *rbd_dev) 527 { 528 struct rbd_image_header *header = &rbd_dev->header; 529 530 if (!rbd_dev->cur_snap) 531 return 0; 532 533 return header->snapc->snaps[snap_index(header, rbd_dev->cur_snap)]; 534 } 535 536 static int snap_by_name(struct rbd_image_header *header, const char *snap_name, 537 u64 *seq, u64 *size) 538 { 539 int i; 540 char *p = header->snap_names; 541 542 for (i = 0; i < header->total_snaps; i++, p += strlen(p) + 1) { 543 if (strcmp(snap_name, p) == 0) 544 break; 545 } 546 if (i == header->total_snaps) 547 return -ENOENT; 548 if (seq) 549 *seq = header->snapc->snaps[i]; 550 551 if (size) 552 *size = header->snap_sizes[i]; 553 554 return i; 555 } 556 557 static int rbd_header_set_snap(struct rbd_device *dev, 558 const char *snap_name, 559 u64 *size) 560 { 561 struct rbd_image_header *header = &dev->header; 562 struct ceph_snap_context *snapc = header->snapc; 563 int ret = -ENOENT; 564 565 down_write(&header->snap_rwsem); 566 567 if (!snap_name || 568 !*snap_name || 569 strcmp(snap_name, "-") == 0 || 570 strcmp(snap_name, RBD_SNAP_HEAD_NAME) == 0) { 571 if (header->total_snaps) 572 snapc->seq = header->snap_seq; 573 else 574 snapc->seq = 0; 575 dev->cur_snap = 0; 576 dev->read_only = 0; 577 if (size) 578 *size = header->image_size; 579 } else { 580 ret = snap_by_name(header, snap_name, &snapc->seq, size); 581 if (ret < 0) 582 goto done; 583 584 dev->cur_snap = header->total_snaps - ret; 585 dev->read_only = 1; 586 } 587 588 ret = 0; 589 done: 590 up_write(&header->snap_rwsem); 591 return ret; 592 } 593 594 static void rbd_header_free(struct rbd_image_header *header) 595 { 596 kfree(header->snapc); 597 kfree(header->snap_names); 598 kfree(header->snap_sizes); 599 } 600 601 /* 602 * get the actual striped segment name, offset and length 603 */ 604 static u64 rbd_get_segment(struct rbd_image_header *header, 605 const char *block_name, 606 u64 ofs, u64 len, 607 char *seg_name, u64 *segofs) 608 { 609 u64 seg = ofs >> header->obj_order; 610 611 if (seg_name) 612 snprintf(seg_name, RBD_MAX_SEG_NAME_LEN, 613 "%s.%012llx", block_name, seg); 614 615 ofs = ofs & ((1 << header->obj_order) - 1); 616 len = min_t(u64, len, (1 << header->obj_order) - ofs); 617 618 if (segofs) 619 *segofs = ofs; 620 621 return len; 622 } 623 624 static int rbd_get_num_segments(struct rbd_image_header *header, 625 u64 ofs, u64 len) 626 { 627 u64 start_seg = ofs >> header->obj_order; 628 u64 end_seg = (ofs + len - 1) >> header->obj_order; 629 return end_seg - start_seg + 1; 630 } 631 632 /* 633 * returns the size of an object in the image 634 */ 635 static u64 rbd_obj_bytes(struct rbd_image_header *header) 636 { 637 return 1 << header->obj_order; 638 } 639 640 /* 641 * bio helpers 642 */ 643 644 static void bio_chain_put(struct bio *chain) 645 { 646 struct bio *tmp; 647 648 while (chain) { 649 tmp = chain; 650 chain = chain->bi_next; 651 bio_put(tmp); 652 } 653 } 654 655 /* 656 * zeros a bio chain, starting at specific offset 657 */ 658 static void zero_bio_chain(struct bio *chain, int start_ofs) 659 { 660 struct bio_vec *bv; 661 unsigned long flags; 662 void *buf; 663 int i; 664 int pos = 0; 665 666 while (chain) { 667 bio_for_each_segment(bv, chain, i) { 668 if (pos + bv->bv_len > start_ofs) { 669 int remainder = max(start_ofs - pos, 0); 670 buf = bvec_kmap_irq(bv, &flags); 671 memset(buf + remainder, 0, 672 bv->bv_len - remainder); 673 bvec_kunmap_irq(buf, &flags); 674 } 675 pos += bv->bv_len; 676 } 677 678 chain = chain->bi_next; 679 } 680 } 681 682 /* 683 * bio_chain_clone - clone a chain of bios up to a certain length. 684 * might return a bio_pair that will need to be released. 685 */ 686 static struct bio *bio_chain_clone(struct bio **old, struct bio **next, 687 struct bio_pair **bp, 688 int len, gfp_t gfpmask) 689 { 690 struct bio *tmp, *old_chain = *old, *new_chain = NULL, *tail = NULL; 691 int total = 0; 692 693 if (*bp) { 694 bio_pair_release(*bp); 695 *bp = NULL; 696 } 697 698 while (old_chain && (total < len)) { 699 tmp = bio_kmalloc(gfpmask, old_chain->bi_max_vecs); 700 if (!tmp) 701 goto err_out; 702 703 if (total + old_chain->bi_size > len) { 704 struct bio_pair *bp; 705 706 /* 707 * this split can only happen with a single paged bio, 708 * split_bio will BUG_ON if this is not the case 709 */ 710 dout("bio_chain_clone split! total=%d remaining=%d" 711 "bi_size=%d\n", 712 (int)total, (int)len-total, 713 (int)old_chain->bi_size); 714 715 /* split the bio. We'll release it either in the next 716 call, or it will have to be released outside */ 717 bp = bio_split(old_chain, (len - total) / 512ULL); 718 if (!bp) 719 goto err_out; 720 721 __bio_clone(tmp, &bp->bio1); 722 723 *next = &bp->bio2; 724 } else { 725 __bio_clone(tmp, old_chain); 726 *next = old_chain->bi_next; 727 } 728 729 tmp->bi_bdev = NULL; 730 gfpmask &= ~__GFP_WAIT; 731 tmp->bi_next = NULL; 732 733 if (!new_chain) { 734 new_chain = tail = tmp; 735 } else { 736 tail->bi_next = tmp; 737 tail = tmp; 738 } 739 old_chain = old_chain->bi_next; 740 741 total += tmp->bi_size; 742 } 743 744 BUG_ON(total < len); 745 746 if (tail) 747 tail->bi_next = NULL; 748 749 *old = old_chain; 750 751 return new_chain; 752 753 err_out: 754 dout("bio_chain_clone with err\n"); 755 bio_chain_put(new_chain); 756 return NULL; 757 } 758 759 /* 760 * helpers for osd request op vectors. 761 */ 762 static int rbd_create_rw_ops(struct ceph_osd_req_op **ops, 763 int num_ops, 764 int opcode, 765 u32 payload_len) 766 { 767 *ops = kzalloc(sizeof(struct ceph_osd_req_op) * (num_ops + 1), 768 GFP_NOIO); 769 if (!*ops) 770 return -ENOMEM; 771 (*ops)[0].op = opcode; 772 /* 773 * op extent offset and length will be set later on 774 * in calc_raw_layout() 775 */ 776 (*ops)[0].payload_len = payload_len; 777 return 0; 778 } 779 780 static void rbd_destroy_ops(struct ceph_osd_req_op *ops) 781 { 782 kfree(ops); 783 } 784 785 static void rbd_coll_end_req_index(struct request *rq, 786 struct rbd_req_coll *coll, 787 int index, 788 int ret, u64 len) 789 { 790 struct request_queue *q; 791 int min, max, i; 792 793 dout("rbd_coll_end_req_index %p index %d ret %d len %lld\n", 794 coll, index, ret, len); 795 796 if (!rq) 797 return; 798 799 if (!coll) { 800 blk_end_request(rq, ret, len); 801 return; 802 } 803 804 q = rq->q; 805 806 spin_lock_irq(q->queue_lock); 807 coll->status[index].done = 1; 808 coll->status[index].rc = ret; 809 coll->status[index].bytes = len; 810 max = min = coll->num_done; 811 while (max < coll->total && coll->status[max].done) 812 max++; 813 814 for (i = min; i<max; i++) { 815 __blk_end_request(rq, coll->status[i].rc, 816 coll->status[i].bytes); 817 coll->num_done++; 818 kref_put(&coll->kref, rbd_coll_release); 819 } 820 spin_unlock_irq(q->queue_lock); 821 } 822 823 static void rbd_coll_end_req(struct rbd_request *req, 824 int ret, u64 len) 825 { 826 rbd_coll_end_req_index(req->rq, req->coll, req->coll_index, ret, len); 827 } 828 829 /* 830 * Send ceph osd request 831 */ 832 static int rbd_do_request(struct request *rq, 833 struct rbd_device *dev, 834 struct ceph_snap_context *snapc, 835 u64 snapid, 836 const char *obj, u64 ofs, u64 len, 837 struct bio *bio, 838 struct page **pages, 839 int num_pages, 840 int flags, 841 struct ceph_osd_req_op *ops, 842 int num_reply, 843 struct rbd_req_coll *coll, 844 int coll_index, 845 void (*rbd_cb)(struct ceph_osd_request *req, 846 struct ceph_msg *msg), 847 struct ceph_osd_request **linger_req, 848 u64 *ver) 849 { 850 struct ceph_osd_request *req; 851 struct ceph_file_layout *layout; 852 int ret; 853 u64 bno; 854 struct timespec mtime = CURRENT_TIME; 855 struct rbd_request *req_data; 856 struct ceph_osd_request_head *reqhead; 857 struct rbd_image_header *header = &dev->header; 858 859 req_data = kzalloc(sizeof(*req_data), GFP_NOIO); 860 if (!req_data) { 861 if (coll) 862 rbd_coll_end_req_index(rq, coll, coll_index, 863 -ENOMEM, len); 864 return -ENOMEM; 865 } 866 867 if (coll) { 868 req_data->coll = coll; 869 req_data->coll_index = coll_index; 870 } 871 872 dout("rbd_do_request obj=%s ofs=%lld len=%lld\n", obj, len, ofs); 873 874 down_read(&header->snap_rwsem); 875 876 req = ceph_osdc_alloc_request(&dev->client->osdc, flags, 877 snapc, 878 ops, 879 false, 880 GFP_NOIO, pages, bio); 881 if (!req) { 882 up_read(&header->snap_rwsem); 883 ret = -ENOMEM; 884 goto done_pages; 885 } 886 887 req->r_callback = rbd_cb; 888 889 req_data->rq = rq; 890 req_data->bio = bio; 891 req_data->pages = pages; 892 req_data->len = len; 893 894 req->r_priv = req_data; 895 896 reqhead = req->r_request->front.iov_base; 897 reqhead->snapid = cpu_to_le64(CEPH_NOSNAP); 898 899 strncpy(req->r_oid, obj, sizeof(req->r_oid)); 900 req->r_oid_len = strlen(req->r_oid); 901 902 layout = &req->r_file_layout; 903 memset(layout, 0, sizeof(*layout)); 904 layout->fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER); 905 layout->fl_stripe_count = cpu_to_le32(1); 906 layout->fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER); 907 layout->fl_pg_preferred = cpu_to_le32(-1); 908 layout->fl_pg_pool = cpu_to_le32(dev->poolid); 909 ceph_calc_raw_layout(&dev->client->osdc, layout, snapid, 910 ofs, &len, &bno, req, ops); 911 912 ceph_osdc_build_request(req, ofs, &len, 913 ops, 914 snapc, 915 &mtime, 916 req->r_oid, req->r_oid_len); 917 up_read(&header->snap_rwsem); 918 919 if (linger_req) { 920 ceph_osdc_set_request_linger(&dev->client->osdc, req); 921 *linger_req = req; 922 } 923 924 ret = ceph_osdc_start_request(&dev->client->osdc, req, false); 925 if (ret < 0) 926 goto done_err; 927 928 if (!rbd_cb) { 929 ret = ceph_osdc_wait_request(&dev->client->osdc, req); 930 if (ver) 931 *ver = le64_to_cpu(req->r_reassert_version.version); 932 dout("reassert_ver=%lld\n", 933 le64_to_cpu(req->r_reassert_version.version)); 934 ceph_osdc_put_request(req); 935 } 936 return ret; 937 938 done_err: 939 bio_chain_put(req_data->bio); 940 ceph_osdc_put_request(req); 941 done_pages: 942 rbd_coll_end_req(req_data, ret, len); 943 kfree(req_data); 944 return ret; 945 } 946 947 /* 948 * Ceph osd op callback 949 */ 950 static void rbd_req_cb(struct ceph_osd_request *req, struct ceph_msg *msg) 951 { 952 struct rbd_request *req_data = req->r_priv; 953 struct ceph_osd_reply_head *replyhead; 954 struct ceph_osd_op *op; 955 __s32 rc; 956 u64 bytes; 957 int read_op; 958 959 /* parse reply */ 960 replyhead = msg->front.iov_base; 961 WARN_ON(le32_to_cpu(replyhead->num_ops) == 0); 962 op = (void *)(replyhead + 1); 963 rc = le32_to_cpu(replyhead->result); 964 bytes = le64_to_cpu(op->extent.length); 965 read_op = (le32_to_cpu(op->op) == CEPH_OSD_OP_READ); 966 967 dout("rbd_req_cb bytes=%lld readop=%d rc=%d\n", bytes, read_op, rc); 968 969 if (rc == -ENOENT && read_op) { 970 zero_bio_chain(req_data->bio, 0); 971 rc = 0; 972 } else if (rc == 0 && read_op && bytes < req_data->len) { 973 zero_bio_chain(req_data->bio, bytes); 974 bytes = req_data->len; 975 } 976 977 rbd_coll_end_req(req_data, rc, bytes); 978 979 if (req_data->bio) 980 bio_chain_put(req_data->bio); 981 982 ceph_osdc_put_request(req); 983 kfree(req_data); 984 } 985 986 static void rbd_simple_req_cb(struct ceph_osd_request *req, struct ceph_msg *msg) 987 { 988 ceph_osdc_put_request(req); 989 } 990 991 /* 992 * Do a synchronous ceph osd operation 993 */ 994 static int rbd_req_sync_op(struct rbd_device *dev, 995 struct ceph_snap_context *snapc, 996 u64 snapid, 997 int opcode, 998 int flags, 999 struct ceph_osd_req_op *orig_ops, 1000 int num_reply, 1001 const char *obj, 1002 u64 ofs, u64 len, 1003 char *buf, 1004 struct ceph_osd_request **linger_req, 1005 u64 *ver) 1006 { 1007 int ret; 1008 struct page **pages; 1009 int num_pages; 1010 struct ceph_osd_req_op *ops = orig_ops; 1011 u32 payload_len; 1012 1013 num_pages = calc_pages_for(ofs , len); 1014 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL); 1015 if (IS_ERR(pages)) 1016 return PTR_ERR(pages); 1017 1018 if (!orig_ops) { 1019 payload_len = (flags & CEPH_OSD_FLAG_WRITE ? len : 0); 1020 ret = rbd_create_rw_ops(&ops, 1, opcode, payload_len); 1021 if (ret < 0) 1022 goto done; 1023 1024 if ((flags & CEPH_OSD_FLAG_WRITE) && buf) { 1025 ret = ceph_copy_to_page_vector(pages, buf, ofs, len); 1026 if (ret < 0) 1027 goto done_ops; 1028 } 1029 } 1030 1031 ret = rbd_do_request(NULL, dev, snapc, snapid, 1032 obj, ofs, len, NULL, 1033 pages, num_pages, 1034 flags, 1035 ops, 1036 2, 1037 NULL, 0, 1038 NULL, 1039 linger_req, ver); 1040 if (ret < 0) 1041 goto done_ops; 1042 1043 if ((flags & CEPH_OSD_FLAG_READ) && buf) 1044 ret = ceph_copy_from_page_vector(pages, buf, ofs, ret); 1045 1046 done_ops: 1047 if (!orig_ops) 1048 rbd_destroy_ops(ops); 1049 done: 1050 ceph_release_page_vector(pages, num_pages); 1051 return ret; 1052 } 1053 1054 /* 1055 * Do an asynchronous ceph osd operation 1056 */ 1057 static int rbd_do_op(struct request *rq, 1058 struct rbd_device *rbd_dev , 1059 struct ceph_snap_context *snapc, 1060 u64 snapid, 1061 int opcode, int flags, int num_reply, 1062 u64 ofs, u64 len, 1063 struct bio *bio, 1064 struct rbd_req_coll *coll, 1065 int coll_index) 1066 { 1067 char *seg_name; 1068 u64 seg_ofs; 1069 u64 seg_len; 1070 int ret; 1071 struct ceph_osd_req_op *ops; 1072 u32 payload_len; 1073 1074 seg_name = kmalloc(RBD_MAX_SEG_NAME_LEN + 1, GFP_NOIO); 1075 if (!seg_name) 1076 return -ENOMEM; 1077 1078 seg_len = rbd_get_segment(&rbd_dev->header, 1079 rbd_dev->header.block_name, 1080 ofs, len, 1081 seg_name, &seg_ofs); 1082 1083 payload_len = (flags & CEPH_OSD_FLAG_WRITE ? seg_len : 0); 1084 1085 ret = rbd_create_rw_ops(&ops, 1, opcode, payload_len); 1086 if (ret < 0) 1087 goto done; 1088 1089 /* we've taken care of segment sizes earlier when we 1090 cloned the bios. We should never have a segment 1091 truncated at this point */ 1092 BUG_ON(seg_len < len); 1093 1094 ret = rbd_do_request(rq, rbd_dev, snapc, snapid, 1095 seg_name, seg_ofs, seg_len, 1096 bio, 1097 NULL, 0, 1098 flags, 1099 ops, 1100 num_reply, 1101 coll, coll_index, 1102 rbd_req_cb, 0, NULL); 1103 1104 rbd_destroy_ops(ops); 1105 done: 1106 kfree(seg_name); 1107 return ret; 1108 } 1109 1110 /* 1111 * Request async osd write 1112 */ 1113 static int rbd_req_write(struct request *rq, 1114 struct rbd_device *rbd_dev, 1115 struct ceph_snap_context *snapc, 1116 u64 ofs, u64 len, 1117 struct bio *bio, 1118 struct rbd_req_coll *coll, 1119 int coll_index) 1120 { 1121 return rbd_do_op(rq, rbd_dev, snapc, CEPH_NOSNAP, 1122 CEPH_OSD_OP_WRITE, 1123 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK, 1124 2, 1125 ofs, len, bio, coll, coll_index); 1126 } 1127 1128 /* 1129 * Request async osd read 1130 */ 1131 static int rbd_req_read(struct request *rq, 1132 struct rbd_device *rbd_dev, 1133 u64 snapid, 1134 u64 ofs, u64 len, 1135 struct bio *bio, 1136 struct rbd_req_coll *coll, 1137 int coll_index) 1138 { 1139 return rbd_do_op(rq, rbd_dev, NULL, 1140 (snapid ? snapid : CEPH_NOSNAP), 1141 CEPH_OSD_OP_READ, 1142 CEPH_OSD_FLAG_READ, 1143 2, 1144 ofs, len, bio, coll, coll_index); 1145 } 1146 1147 /* 1148 * Request sync osd read 1149 */ 1150 static int rbd_req_sync_read(struct rbd_device *dev, 1151 struct ceph_snap_context *snapc, 1152 u64 snapid, 1153 const char *obj, 1154 u64 ofs, u64 len, 1155 char *buf, 1156 u64 *ver) 1157 { 1158 return rbd_req_sync_op(dev, NULL, 1159 (snapid ? snapid : CEPH_NOSNAP), 1160 CEPH_OSD_OP_READ, 1161 CEPH_OSD_FLAG_READ, 1162 NULL, 1163 1, obj, ofs, len, buf, NULL, ver); 1164 } 1165 1166 /* 1167 * Request sync osd watch 1168 */ 1169 static int rbd_req_sync_notify_ack(struct rbd_device *dev, 1170 u64 ver, 1171 u64 notify_id, 1172 const char *obj) 1173 { 1174 struct ceph_osd_req_op *ops; 1175 struct page **pages = NULL; 1176 int ret; 1177 1178 ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_NOTIFY_ACK, 0); 1179 if (ret < 0) 1180 return ret; 1181 1182 ops[0].watch.ver = cpu_to_le64(dev->header.obj_version); 1183 ops[0].watch.cookie = notify_id; 1184 ops[0].watch.flag = 0; 1185 1186 ret = rbd_do_request(NULL, dev, NULL, CEPH_NOSNAP, 1187 obj, 0, 0, NULL, 1188 pages, 0, 1189 CEPH_OSD_FLAG_READ, 1190 ops, 1191 1, 1192 NULL, 0, 1193 rbd_simple_req_cb, 0, NULL); 1194 1195 rbd_destroy_ops(ops); 1196 return ret; 1197 } 1198 1199 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data) 1200 { 1201 struct rbd_device *dev = (struct rbd_device *)data; 1202 int rc; 1203 1204 if (!dev) 1205 return; 1206 1207 dout("rbd_watch_cb %s notify_id=%lld opcode=%d\n", dev->obj_md_name, 1208 notify_id, (int)opcode); 1209 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 1210 rc = __rbd_update_snaps(dev); 1211 mutex_unlock(&ctl_mutex); 1212 if (rc) 1213 pr_warning(DRV_NAME "%d got notification but failed to update" 1214 " snaps: %d\n", dev->major, rc); 1215 1216 rbd_req_sync_notify_ack(dev, ver, notify_id, dev->obj_md_name); 1217 } 1218 1219 /* 1220 * Request sync osd watch 1221 */ 1222 static int rbd_req_sync_watch(struct rbd_device *dev, 1223 const char *obj, 1224 u64 ver) 1225 { 1226 struct ceph_osd_req_op *ops; 1227 struct ceph_osd_client *osdc = &dev->client->osdc; 1228 1229 int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_WATCH, 0); 1230 if (ret < 0) 1231 return ret; 1232 1233 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, 0, 1234 (void *)dev, &dev->watch_event); 1235 if (ret < 0) 1236 goto fail; 1237 1238 ops[0].watch.ver = cpu_to_le64(ver); 1239 ops[0].watch.cookie = cpu_to_le64(dev->watch_event->cookie); 1240 ops[0].watch.flag = 1; 1241 1242 ret = rbd_req_sync_op(dev, NULL, 1243 CEPH_NOSNAP, 1244 0, 1245 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK, 1246 ops, 1247 1, obj, 0, 0, NULL, 1248 &dev->watch_request, NULL); 1249 1250 if (ret < 0) 1251 goto fail_event; 1252 1253 rbd_destroy_ops(ops); 1254 return 0; 1255 1256 fail_event: 1257 ceph_osdc_cancel_event(dev->watch_event); 1258 dev->watch_event = NULL; 1259 fail: 1260 rbd_destroy_ops(ops); 1261 return ret; 1262 } 1263 1264 /* 1265 * Request sync osd unwatch 1266 */ 1267 static int rbd_req_sync_unwatch(struct rbd_device *dev, 1268 const char *obj) 1269 { 1270 struct ceph_osd_req_op *ops; 1271 1272 int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_WATCH, 0); 1273 if (ret < 0) 1274 return ret; 1275 1276 ops[0].watch.ver = 0; 1277 ops[0].watch.cookie = cpu_to_le64(dev->watch_event->cookie); 1278 ops[0].watch.flag = 0; 1279 1280 ret = rbd_req_sync_op(dev, NULL, 1281 CEPH_NOSNAP, 1282 0, 1283 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK, 1284 ops, 1285 1, obj, 0, 0, NULL, NULL, NULL); 1286 1287 rbd_destroy_ops(ops); 1288 ceph_osdc_cancel_event(dev->watch_event); 1289 dev->watch_event = NULL; 1290 return ret; 1291 } 1292 1293 struct rbd_notify_info { 1294 struct rbd_device *dev; 1295 }; 1296 1297 static void rbd_notify_cb(u64 ver, u64 notify_id, u8 opcode, void *data) 1298 { 1299 struct rbd_device *dev = (struct rbd_device *)data; 1300 if (!dev) 1301 return; 1302 1303 dout("rbd_notify_cb %s notify_id=%lld opcode=%d\n", dev->obj_md_name, 1304 notify_id, (int)opcode); 1305 } 1306 1307 /* 1308 * Request sync osd notify 1309 */ 1310 static int rbd_req_sync_notify(struct rbd_device *dev, 1311 const char *obj) 1312 { 1313 struct ceph_osd_req_op *ops; 1314 struct ceph_osd_client *osdc = &dev->client->osdc; 1315 struct ceph_osd_event *event; 1316 struct rbd_notify_info info; 1317 int payload_len = sizeof(u32) + sizeof(u32); 1318 int ret; 1319 1320 ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_NOTIFY, payload_len); 1321 if (ret < 0) 1322 return ret; 1323 1324 info.dev = dev; 1325 1326 ret = ceph_osdc_create_event(osdc, rbd_notify_cb, 1, 1327 (void *)&info, &event); 1328 if (ret < 0) 1329 goto fail; 1330 1331 ops[0].watch.ver = 1; 1332 ops[0].watch.flag = 1; 1333 ops[0].watch.cookie = event->cookie; 1334 ops[0].watch.prot_ver = RADOS_NOTIFY_VER; 1335 ops[0].watch.timeout = 12; 1336 1337 ret = rbd_req_sync_op(dev, NULL, 1338 CEPH_NOSNAP, 1339 0, 1340 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK, 1341 ops, 1342 1, obj, 0, 0, NULL, NULL, NULL); 1343 if (ret < 0) 1344 goto fail_event; 1345 1346 ret = ceph_osdc_wait_event(event, CEPH_OSD_TIMEOUT_DEFAULT); 1347 dout("ceph_osdc_wait_event returned %d\n", ret); 1348 rbd_destroy_ops(ops); 1349 return 0; 1350 1351 fail_event: 1352 ceph_osdc_cancel_event(event); 1353 fail: 1354 rbd_destroy_ops(ops); 1355 return ret; 1356 } 1357 1358 /* 1359 * Request sync osd rollback 1360 */ 1361 static int rbd_req_sync_rollback_obj(struct rbd_device *dev, 1362 u64 snapid, 1363 const char *obj) 1364 { 1365 struct ceph_osd_req_op *ops; 1366 int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_ROLLBACK, 0); 1367 if (ret < 0) 1368 return ret; 1369 1370 ops[0].snap.snapid = snapid; 1371 1372 ret = rbd_req_sync_op(dev, NULL, 1373 CEPH_NOSNAP, 1374 0, 1375 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK, 1376 ops, 1377 1, obj, 0, 0, NULL, NULL, NULL); 1378 1379 rbd_destroy_ops(ops); 1380 1381 return ret; 1382 } 1383 1384 /* 1385 * Request sync osd read 1386 */ 1387 static int rbd_req_sync_exec(struct rbd_device *dev, 1388 const char *obj, 1389 const char *cls, 1390 const char *method, 1391 const char *data, 1392 int len, 1393 u64 *ver) 1394 { 1395 struct ceph_osd_req_op *ops; 1396 int cls_len = strlen(cls); 1397 int method_len = strlen(method); 1398 int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_CALL, 1399 cls_len + method_len + len); 1400 if (ret < 0) 1401 return ret; 1402 1403 ops[0].cls.class_name = cls; 1404 ops[0].cls.class_len = (__u8)cls_len; 1405 ops[0].cls.method_name = method; 1406 ops[0].cls.method_len = (__u8)method_len; 1407 ops[0].cls.argc = 0; 1408 ops[0].cls.indata = data; 1409 ops[0].cls.indata_len = len; 1410 1411 ret = rbd_req_sync_op(dev, NULL, 1412 CEPH_NOSNAP, 1413 0, 1414 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK, 1415 ops, 1416 1, obj, 0, 0, NULL, NULL, ver); 1417 1418 rbd_destroy_ops(ops); 1419 1420 dout("cls_exec returned %d\n", ret); 1421 return ret; 1422 } 1423 1424 static struct rbd_req_coll *rbd_alloc_coll(int num_reqs) 1425 { 1426 struct rbd_req_coll *coll = 1427 kzalloc(sizeof(struct rbd_req_coll) + 1428 sizeof(struct rbd_req_status) * num_reqs, 1429 GFP_ATOMIC); 1430 1431 if (!coll) 1432 return NULL; 1433 coll->total = num_reqs; 1434 kref_init(&coll->kref); 1435 return coll; 1436 } 1437 1438 /* 1439 * block device queue callback 1440 */ 1441 static void rbd_rq_fn(struct request_queue *q) 1442 { 1443 struct rbd_device *rbd_dev = q->queuedata; 1444 struct request *rq; 1445 struct bio_pair *bp = NULL; 1446 1447 rq = blk_fetch_request(q); 1448 1449 while (1) { 1450 struct bio *bio; 1451 struct bio *rq_bio, *next_bio = NULL; 1452 bool do_write; 1453 int size, op_size = 0; 1454 u64 ofs; 1455 int num_segs, cur_seg = 0; 1456 struct rbd_req_coll *coll; 1457 1458 /* peek at request from block layer */ 1459 if (!rq) 1460 break; 1461 1462 dout("fetched request\n"); 1463 1464 /* filter out block requests we don't understand */ 1465 if ((rq->cmd_type != REQ_TYPE_FS)) { 1466 __blk_end_request_all(rq, 0); 1467 goto next; 1468 } 1469 1470 /* deduce our operation (read, write) */ 1471 do_write = (rq_data_dir(rq) == WRITE); 1472 1473 size = blk_rq_bytes(rq); 1474 ofs = blk_rq_pos(rq) * 512ULL; 1475 rq_bio = rq->bio; 1476 if (do_write && rbd_dev->read_only) { 1477 __blk_end_request_all(rq, -EROFS); 1478 goto next; 1479 } 1480 1481 spin_unlock_irq(q->queue_lock); 1482 1483 dout("%s 0x%x bytes at 0x%llx\n", 1484 do_write ? "write" : "read", 1485 size, blk_rq_pos(rq) * 512ULL); 1486 1487 num_segs = rbd_get_num_segments(&rbd_dev->header, ofs, size); 1488 coll = rbd_alloc_coll(num_segs); 1489 if (!coll) { 1490 spin_lock_irq(q->queue_lock); 1491 __blk_end_request_all(rq, -ENOMEM); 1492 goto next; 1493 } 1494 1495 do { 1496 /* a bio clone to be passed down to OSD req */ 1497 dout("rq->bio->bi_vcnt=%d\n", rq->bio->bi_vcnt); 1498 op_size = rbd_get_segment(&rbd_dev->header, 1499 rbd_dev->header.block_name, 1500 ofs, size, 1501 NULL, NULL); 1502 kref_get(&coll->kref); 1503 bio = bio_chain_clone(&rq_bio, &next_bio, &bp, 1504 op_size, GFP_ATOMIC); 1505 if (!bio) { 1506 rbd_coll_end_req_index(rq, coll, cur_seg, 1507 -ENOMEM, op_size); 1508 goto next_seg; 1509 } 1510 1511 1512 /* init OSD command: write or read */ 1513 if (do_write) 1514 rbd_req_write(rq, rbd_dev, 1515 rbd_dev->header.snapc, 1516 ofs, 1517 op_size, bio, 1518 coll, cur_seg); 1519 else 1520 rbd_req_read(rq, rbd_dev, 1521 cur_snap_id(rbd_dev), 1522 ofs, 1523 op_size, bio, 1524 coll, cur_seg); 1525 1526 next_seg: 1527 size -= op_size; 1528 ofs += op_size; 1529 1530 cur_seg++; 1531 rq_bio = next_bio; 1532 } while (size > 0); 1533 kref_put(&coll->kref, rbd_coll_release); 1534 1535 if (bp) 1536 bio_pair_release(bp); 1537 spin_lock_irq(q->queue_lock); 1538 next: 1539 rq = blk_fetch_request(q); 1540 } 1541 } 1542 1543 /* 1544 * a queue callback. Makes sure that we don't create a bio that spans across 1545 * multiple osd objects. One exception would be with a single page bios, 1546 * which we handle later at bio_chain_clone 1547 */ 1548 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd, 1549 struct bio_vec *bvec) 1550 { 1551 struct rbd_device *rbd_dev = q->queuedata; 1552 unsigned int chunk_sectors = 1 << (rbd_dev->header.obj_order - 9); 1553 sector_t sector = bmd->bi_sector + get_start_sect(bmd->bi_bdev); 1554 unsigned int bio_sectors = bmd->bi_size >> 9; 1555 int max; 1556 1557 max = (chunk_sectors - ((sector & (chunk_sectors - 1)) 1558 + bio_sectors)) << 9; 1559 if (max < 0) 1560 max = 0; /* bio_add cannot handle a negative return */ 1561 if (max <= bvec->bv_len && bio_sectors == 0) 1562 return bvec->bv_len; 1563 return max; 1564 } 1565 1566 static void rbd_free_disk(struct rbd_device *rbd_dev) 1567 { 1568 struct gendisk *disk = rbd_dev->disk; 1569 1570 if (!disk) 1571 return; 1572 1573 rbd_header_free(&rbd_dev->header); 1574 1575 if (disk->flags & GENHD_FL_UP) 1576 del_gendisk(disk); 1577 if (disk->queue) 1578 blk_cleanup_queue(disk->queue); 1579 put_disk(disk); 1580 } 1581 1582 /* 1583 * reload the ondisk the header 1584 */ 1585 static int rbd_read_header(struct rbd_device *rbd_dev, 1586 struct rbd_image_header *header) 1587 { 1588 ssize_t rc; 1589 struct rbd_image_header_ondisk *dh; 1590 int snap_count = 0; 1591 u64 snap_names_len = 0; 1592 u64 ver; 1593 1594 while (1) { 1595 int len = sizeof(*dh) + 1596 snap_count * sizeof(struct rbd_image_snap_ondisk) + 1597 snap_names_len; 1598 1599 rc = -ENOMEM; 1600 dh = kmalloc(len, GFP_KERNEL); 1601 if (!dh) 1602 return -ENOMEM; 1603 1604 rc = rbd_req_sync_read(rbd_dev, 1605 NULL, CEPH_NOSNAP, 1606 rbd_dev->obj_md_name, 1607 0, len, 1608 (char *)dh, &ver); 1609 if (rc < 0) 1610 goto out_dh; 1611 1612 rc = rbd_header_from_disk(header, dh, snap_count, GFP_KERNEL); 1613 if (rc < 0) 1614 goto out_dh; 1615 1616 if (snap_count != header->total_snaps) { 1617 snap_count = header->total_snaps; 1618 snap_names_len = header->snap_names_len; 1619 rbd_header_free(header); 1620 kfree(dh); 1621 continue; 1622 } 1623 break; 1624 } 1625 header->obj_version = ver; 1626 1627 out_dh: 1628 kfree(dh); 1629 return rc; 1630 } 1631 1632 /* 1633 * create a snapshot 1634 */ 1635 static int rbd_header_add_snap(struct rbd_device *dev, 1636 const char *snap_name, 1637 gfp_t gfp_flags) 1638 { 1639 int name_len = strlen(snap_name); 1640 u64 new_snapid; 1641 int ret; 1642 void *data, *p, *e; 1643 u64 ver; 1644 1645 /* we should create a snapshot only if we're pointing at the head */ 1646 if (dev->cur_snap) 1647 return -EINVAL; 1648 1649 ret = ceph_monc_create_snapid(&dev->client->monc, dev->poolid, 1650 &new_snapid); 1651 dout("created snapid=%lld\n", new_snapid); 1652 if (ret < 0) 1653 return ret; 1654 1655 data = kmalloc(name_len + 16, gfp_flags); 1656 if (!data) 1657 return -ENOMEM; 1658 1659 p = data; 1660 e = data + name_len + 16; 1661 1662 ceph_encode_string_safe(&p, e, snap_name, name_len, bad); 1663 ceph_encode_64_safe(&p, e, new_snapid, bad); 1664 1665 ret = rbd_req_sync_exec(dev, dev->obj_md_name, "rbd", "snap_add", 1666 data, p - data, &ver); 1667 1668 kfree(data); 1669 1670 if (ret < 0) 1671 return ret; 1672 1673 dev->header.snapc->seq = new_snapid; 1674 1675 return 0; 1676 bad: 1677 return -ERANGE; 1678 } 1679 1680 static void __rbd_remove_all_snaps(struct rbd_device *rbd_dev) 1681 { 1682 struct rbd_snap *snap; 1683 1684 while (!list_empty(&rbd_dev->snaps)) { 1685 snap = list_first_entry(&rbd_dev->snaps, struct rbd_snap, node); 1686 __rbd_remove_snap_dev(rbd_dev, snap); 1687 } 1688 } 1689 1690 /* 1691 * only read the first part of the ondisk header, without the snaps info 1692 */ 1693 static int __rbd_update_snaps(struct rbd_device *rbd_dev) 1694 { 1695 int ret; 1696 struct rbd_image_header h; 1697 u64 snap_seq; 1698 int follow_seq = 0; 1699 1700 ret = rbd_read_header(rbd_dev, &h); 1701 if (ret < 0) 1702 return ret; 1703 1704 /* resized? */ 1705 set_capacity(rbd_dev->disk, h.image_size / 512ULL); 1706 1707 down_write(&rbd_dev->header.snap_rwsem); 1708 1709 snap_seq = rbd_dev->header.snapc->seq; 1710 if (rbd_dev->header.total_snaps && 1711 rbd_dev->header.snapc->snaps[0] == snap_seq) 1712 /* pointing at the head, will need to follow that 1713 if head moves */ 1714 follow_seq = 1; 1715 1716 kfree(rbd_dev->header.snapc); 1717 kfree(rbd_dev->header.snap_names); 1718 kfree(rbd_dev->header.snap_sizes); 1719 1720 rbd_dev->header.total_snaps = h.total_snaps; 1721 rbd_dev->header.snapc = h.snapc; 1722 rbd_dev->header.snap_names = h.snap_names; 1723 rbd_dev->header.snap_names_len = h.snap_names_len; 1724 rbd_dev->header.snap_sizes = h.snap_sizes; 1725 if (follow_seq) 1726 rbd_dev->header.snapc->seq = rbd_dev->header.snapc->snaps[0]; 1727 else 1728 rbd_dev->header.snapc->seq = snap_seq; 1729 1730 ret = __rbd_init_snaps_header(rbd_dev); 1731 1732 up_write(&rbd_dev->header.snap_rwsem); 1733 1734 return ret; 1735 } 1736 1737 static int rbd_init_disk(struct rbd_device *rbd_dev) 1738 { 1739 struct gendisk *disk; 1740 struct request_queue *q; 1741 int rc; 1742 u64 total_size = 0; 1743 1744 /* contact OSD, request size info about the object being mapped */ 1745 rc = rbd_read_header(rbd_dev, &rbd_dev->header); 1746 if (rc) 1747 return rc; 1748 1749 /* no need to lock here, as rbd_dev is not registered yet */ 1750 rc = __rbd_init_snaps_header(rbd_dev); 1751 if (rc) 1752 return rc; 1753 1754 rc = rbd_header_set_snap(rbd_dev, rbd_dev->snap_name, &total_size); 1755 if (rc) 1756 return rc; 1757 1758 /* create gendisk info */ 1759 rc = -ENOMEM; 1760 disk = alloc_disk(RBD_MINORS_PER_MAJOR); 1761 if (!disk) 1762 goto out; 1763 1764 snprintf(disk->disk_name, sizeof(disk->disk_name), DRV_NAME "%d", 1765 rbd_dev->id); 1766 disk->major = rbd_dev->major; 1767 disk->first_minor = 0; 1768 disk->fops = &rbd_bd_ops; 1769 disk->private_data = rbd_dev; 1770 1771 /* init rq */ 1772 rc = -ENOMEM; 1773 q = blk_init_queue(rbd_rq_fn, &rbd_dev->lock); 1774 if (!q) 1775 goto out_disk; 1776 1777 /* set io sizes to object size */ 1778 blk_queue_max_hw_sectors(q, rbd_obj_bytes(&rbd_dev->header) / 512ULL); 1779 blk_queue_max_segment_size(q, rbd_obj_bytes(&rbd_dev->header)); 1780 blk_queue_io_min(q, rbd_obj_bytes(&rbd_dev->header)); 1781 blk_queue_io_opt(q, rbd_obj_bytes(&rbd_dev->header)); 1782 1783 blk_queue_merge_bvec(q, rbd_merge_bvec); 1784 disk->queue = q; 1785 1786 q->queuedata = rbd_dev; 1787 1788 rbd_dev->disk = disk; 1789 rbd_dev->q = q; 1790 1791 /* finally, announce the disk to the world */ 1792 set_capacity(disk, total_size / 512ULL); 1793 add_disk(disk); 1794 1795 pr_info("%s: added with size 0x%llx\n", 1796 disk->disk_name, (unsigned long long)total_size); 1797 return 0; 1798 1799 out_disk: 1800 put_disk(disk); 1801 out: 1802 return rc; 1803 } 1804 1805 /* 1806 sysfs 1807 */ 1808 1809 static ssize_t rbd_size_show(struct device *dev, 1810 struct device_attribute *attr, char *buf) 1811 { 1812 struct rbd_device *rbd_dev = dev_to_rbd(dev); 1813 1814 return sprintf(buf, "%llu\n", (unsigned long long)rbd_dev->header.image_size); 1815 } 1816 1817 static ssize_t rbd_major_show(struct device *dev, 1818 struct device_attribute *attr, char *buf) 1819 { 1820 struct rbd_device *rbd_dev = dev_to_rbd(dev); 1821 1822 return sprintf(buf, "%d\n", rbd_dev->major); 1823 } 1824 1825 static ssize_t rbd_client_id_show(struct device *dev, 1826 struct device_attribute *attr, char *buf) 1827 { 1828 struct rbd_device *rbd_dev = dev_to_rbd(dev); 1829 1830 return sprintf(buf, "client%lld\n", ceph_client_id(rbd_dev->client)); 1831 } 1832 1833 static ssize_t rbd_pool_show(struct device *dev, 1834 struct device_attribute *attr, char *buf) 1835 { 1836 struct rbd_device *rbd_dev = dev_to_rbd(dev); 1837 1838 return sprintf(buf, "%s\n", rbd_dev->pool_name); 1839 } 1840 1841 static ssize_t rbd_name_show(struct device *dev, 1842 struct device_attribute *attr, char *buf) 1843 { 1844 struct rbd_device *rbd_dev = dev_to_rbd(dev); 1845 1846 return sprintf(buf, "%s\n", rbd_dev->obj); 1847 } 1848 1849 static ssize_t rbd_snap_show(struct device *dev, 1850 struct device_attribute *attr, 1851 char *buf) 1852 { 1853 struct rbd_device *rbd_dev = dev_to_rbd(dev); 1854 1855 return sprintf(buf, "%s\n", rbd_dev->snap_name); 1856 } 1857 1858 static ssize_t rbd_image_refresh(struct device *dev, 1859 struct device_attribute *attr, 1860 const char *buf, 1861 size_t size) 1862 { 1863 struct rbd_device *rbd_dev = dev_to_rbd(dev); 1864 int rc; 1865 int ret = size; 1866 1867 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 1868 1869 rc = __rbd_update_snaps(rbd_dev); 1870 if (rc < 0) 1871 ret = rc; 1872 1873 mutex_unlock(&ctl_mutex); 1874 return ret; 1875 } 1876 1877 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL); 1878 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL); 1879 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL); 1880 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL); 1881 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL); 1882 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh); 1883 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL); 1884 static DEVICE_ATTR(create_snap, S_IWUSR, NULL, rbd_snap_add); 1885 static DEVICE_ATTR(rollback_snap, S_IWUSR, NULL, rbd_snap_rollback); 1886 1887 static struct attribute *rbd_attrs[] = { 1888 &dev_attr_size.attr, 1889 &dev_attr_major.attr, 1890 &dev_attr_client_id.attr, 1891 &dev_attr_pool.attr, 1892 &dev_attr_name.attr, 1893 &dev_attr_current_snap.attr, 1894 &dev_attr_refresh.attr, 1895 &dev_attr_create_snap.attr, 1896 &dev_attr_rollback_snap.attr, 1897 NULL 1898 }; 1899 1900 static struct attribute_group rbd_attr_group = { 1901 .attrs = rbd_attrs, 1902 }; 1903 1904 static const struct attribute_group *rbd_attr_groups[] = { 1905 &rbd_attr_group, 1906 NULL 1907 }; 1908 1909 static void rbd_sysfs_dev_release(struct device *dev) 1910 { 1911 } 1912 1913 static struct device_type rbd_device_type = { 1914 .name = "rbd", 1915 .groups = rbd_attr_groups, 1916 .release = rbd_sysfs_dev_release, 1917 }; 1918 1919 1920 /* 1921 sysfs - snapshots 1922 */ 1923 1924 static ssize_t rbd_snap_size_show(struct device *dev, 1925 struct device_attribute *attr, 1926 char *buf) 1927 { 1928 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev); 1929 1930 return sprintf(buf, "%lld\n", (long long)snap->size); 1931 } 1932 1933 static ssize_t rbd_snap_id_show(struct device *dev, 1934 struct device_attribute *attr, 1935 char *buf) 1936 { 1937 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev); 1938 1939 return sprintf(buf, "%lld\n", (long long)snap->id); 1940 } 1941 1942 static DEVICE_ATTR(snap_size, S_IRUGO, rbd_snap_size_show, NULL); 1943 static DEVICE_ATTR(snap_id, S_IRUGO, rbd_snap_id_show, NULL); 1944 1945 static struct attribute *rbd_snap_attrs[] = { 1946 &dev_attr_snap_size.attr, 1947 &dev_attr_snap_id.attr, 1948 NULL, 1949 }; 1950 1951 static struct attribute_group rbd_snap_attr_group = { 1952 .attrs = rbd_snap_attrs, 1953 }; 1954 1955 static void rbd_snap_dev_release(struct device *dev) 1956 { 1957 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev); 1958 kfree(snap->name); 1959 kfree(snap); 1960 } 1961 1962 static const struct attribute_group *rbd_snap_attr_groups[] = { 1963 &rbd_snap_attr_group, 1964 NULL 1965 }; 1966 1967 static struct device_type rbd_snap_device_type = { 1968 .groups = rbd_snap_attr_groups, 1969 .release = rbd_snap_dev_release, 1970 }; 1971 1972 static void __rbd_remove_snap_dev(struct rbd_device *rbd_dev, 1973 struct rbd_snap *snap) 1974 { 1975 list_del(&snap->node); 1976 device_unregister(&snap->dev); 1977 } 1978 1979 static int rbd_register_snap_dev(struct rbd_device *rbd_dev, 1980 struct rbd_snap *snap, 1981 struct device *parent) 1982 { 1983 struct device *dev = &snap->dev; 1984 int ret; 1985 1986 dev->type = &rbd_snap_device_type; 1987 dev->parent = parent; 1988 dev->release = rbd_snap_dev_release; 1989 dev_set_name(dev, "snap_%s", snap->name); 1990 ret = device_register(dev); 1991 1992 return ret; 1993 } 1994 1995 static int __rbd_add_snap_dev(struct rbd_device *rbd_dev, 1996 int i, const char *name, 1997 struct rbd_snap **snapp) 1998 { 1999 int ret; 2000 struct rbd_snap *snap = kzalloc(sizeof(*snap), GFP_KERNEL); 2001 if (!snap) 2002 return -ENOMEM; 2003 snap->name = kstrdup(name, GFP_KERNEL); 2004 snap->size = rbd_dev->header.snap_sizes[i]; 2005 snap->id = rbd_dev->header.snapc->snaps[i]; 2006 if (device_is_registered(&rbd_dev->dev)) { 2007 ret = rbd_register_snap_dev(rbd_dev, snap, 2008 &rbd_dev->dev); 2009 if (ret < 0) 2010 goto err; 2011 } 2012 *snapp = snap; 2013 return 0; 2014 err: 2015 kfree(snap->name); 2016 kfree(snap); 2017 return ret; 2018 } 2019 2020 /* 2021 * search for the previous snap in a null delimited string list 2022 */ 2023 const char *rbd_prev_snap_name(const char *name, const char *start) 2024 { 2025 if (name < start + 2) 2026 return NULL; 2027 2028 name -= 2; 2029 while (*name) { 2030 if (name == start) 2031 return start; 2032 name--; 2033 } 2034 return name + 1; 2035 } 2036 2037 /* 2038 * compare the old list of snapshots that we have to what's in the header 2039 * and update it accordingly. Note that the header holds the snapshots 2040 * in a reverse order (from newest to oldest) and we need to go from 2041 * older to new so that we don't get a duplicate snap name when 2042 * doing the process (e.g., removed snapshot and recreated a new 2043 * one with the same name. 2044 */ 2045 static int __rbd_init_snaps_header(struct rbd_device *rbd_dev) 2046 { 2047 const char *name, *first_name; 2048 int i = rbd_dev->header.total_snaps; 2049 struct rbd_snap *snap, *old_snap = NULL; 2050 int ret; 2051 struct list_head *p, *n; 2052 2053 first_name = rbd_dev->header.snap_names; 2054 name = first_name + rbd_dev->header.snap_names_len; 2055 2056 list_for_each_prev_safe(p, n, &rbd_dev->snaps) { 2057 u64 cur_id; 2058 2059 old_snap = list_entry(p, struct rbd_snap, node); 2060 2061 if (i) 2062 cur_id = rbd_dev->header.snapc->snaps[i - 1]; 2063 2064 if (!i || old_snap->id < cur_id) { 2065 /* old_snap->id was skipped, thus was removed */ 2066 __rbd_remove_snap_dev(rbd_dev, old_snap); 2067 continue; 2068 } 2069 if (old_snap->id == cur_id) { 2070 /* we have this snapshot already */ 2071 i--; 2072 name = rbd_prev_snap_name(name, first_name); 2073 continue; 2074 } 2075 for (; i > 0; 2076 i--, name = rbd_prev_snap_name(name, first_name)) { 2077 if (!name) { 2078 WARN_ON(1); 2079 return -EINVAL; 2080 } 2081 cur_id = rbd_dev->header.snapc->snaps[i]; 2082 /* snapshot removal? handle it above */ 2083 if (cur_id >= old_snap->id) 2084 break; 2085 /* a new snapshot */ 2086 ret = __rbd_add_snap_dev(rbd_dev, i - 1, name, &snap); 2087 if (ret < 0) 2088 return ret; 2089 2090 /* note that we add it backward so using n and not p */ 2091 list_add(&snap->node, n); 2092 p = &snap->node; 2093 } 2094 } 2095 /* we're done going over the old snap list, just add what's left */ 2096 for (; i > 0; i--) { 2097 name = rbd_prev_snap_name(name, first_name); 2098 if (!name) { 2099 WARN_ON(1); 2100 return -EINVAL; 2101 } 2102 ret = __rbd_add_snap_dev(rbd_dev, i - 1, name, &snap); 2103 if (ret < 0) 2104 return ret; 2105 list_add(&snap->node, &rbd_dev->snaps); 2106 } 2107 2108 return 0; 2109 } 2110 2111 2112 static void rbd_root_dev_release(struct device *dev) 2113 { 2114 } 2115 2116 static struct device rbd_root_dev = { 2117 .init_name = "rbd", 2118 .release = rbd_root_dev_release, 2119 }; 2120 2121 static int rbd_bus_add_dev(struct rbd_device *rbd_dev) 2122 { 2123 int ret = -ENOMEM; 2124 struct device *dev; 2125 struct rbd_snap *snap; 2126 2127 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 2128 dev = &rbd_dev->dev; 2129 2130 dev->bus = &rbd_bus_type; 2131 dev->type = &rbd_device_type; 2132 dev->parent = &rbd_root_dev; 2133 dev->release = rbd_dev_release; 2134 dev_set_name(dev, "%d", rbd_dev->id); 2135 ret = device_register(dev); 2136 if (ret < 0) 2137 goto done_free; 2138 2139 list_for_each_entry(snap, &rbd_dev->snaps, node) { 2140 ret = rbd_register_snap_dev(rbd_dev, snap, 2141 &rbd_dev->dev); 2142 if (ret < 0) 2143 break; 2144 } 2145 2146 mutex_unlock(&ctl_mutex); 2147 return 0; 2148 done_free: 2149 mutex_unlock(&ctl_mutex); 2150 return ret; 2151 } 2152 2153 static void rbd_bus_del_dev(struct rbd_device *rbd_dev) 2154 { 2155 device_unregister(&rbd_dev->dev); 2156 } 2157 2158 static int rbd_init_watch_dev(struct rbd_device *rbd_dev) 2159 { 2160 int ret, rc; 2161 2162 do { 2163 ret = rbd_req_sync_watch(rbd_dev, rbd_dev->obj_md_name, 2164 rbd_dev->header.obj_version); 2165 if (ret == -ERANGE) { 2166 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 2167 rc = __rbd_update_snaps(rbd_dev); 2168 mutex_unlock(&ctl_mutex); 2169 if (rc < 0) 2170 return rc; 2171 } 2172 } while (ret == -ERANGE); 2173 2174 return ret; 2175 } 2176 2177 static ssize_t rbd_add(struct bus_type *bus, 2178 const char *buf, 2179 size_t count) 2180 { 2181 struct ceph_osd_client *osdc; 2182 struct rbd_device *rbd_dev; 2183 ssize_t rc = -ENOMEM; 2184 int irc, new_id = 0; 2185 struct list_head *tmp; 2186 char *mon_dev_name; 2187 char *options; 2188 2189 if (!try_module_get(THIS_MODULE)) 2190 return -ENODEV; 2191 2192 mon_dev_name = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL); 2193 if (!mon_dev_name) 2194 goto err_out_mod; 2195 2196 options = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL); 2197 if (!options) 2198 goto err_mon_dev; 2199 2200 /* new rbd_device object */ 2201 rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL); 2202 if (!rbd_dev) 2203 goto err_out_opt; 2204 2205 /* static rbd_device initialization */ 2206 spin_lock_init(&rbd_dev->lock); 2207 INIT_LIST_HEAD(&rbd_dev->node); 2208 INIT_LIST_HEAD(&rbd_dev->snaps); 2209 2210 /* generate unique id: find highest unique id, add one */ 2211 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 2212 2213 list_for_each(tmp, &rbd_dev_list) { 2214 struct rbd_device *rbd_dev; 2215 2216 rbd_dev = list_entry(tmp, struct rbd_device, node); 2217 if (rbd_dev->id >= new_id) 2218 new_id = rbd_dev->id + 1; 2219 } 2220 2221 rbd_dev->id = new_id; 2222 2223 /* add to global list */ 2224 list_add_tail(&rbd_dev->node, &rbd_dev_list); 2225 2226 /* parse add command */ 2227 if (sscanf(buf, "%" __stringify(RBD_MAX_OPT_LEN) "s " 2228 "%" __stringify(RBD_MAX_OPT_LEN) "s " 2229 "%" __stringify(RBD_MAX_POOL_NAME_LEN) "s " 2230 "%" __stringify(RBD_MAX_OBJ_NAME_LEN) "s" 2231 "%" __stringify(RBD_MAX_SNAP_NAME_LEN) "s", 2232 mon_dev_name, options, rbd_dev->pool_name, 2233 rbd_dev->obj, rbd_dev->snap_name) < 4) { 2234 rc = -EINVAL; 2235 goto err_out_slot; 2236 } 2237 2238 if (rbd_dev->snap_name[0] == 0) 2239 rbd_dev->snap_name[0] = '-'; 2240 2241 rbd_dev->obj_len = strlen(rbd_dev->obj); 2242 snprintf(rbd_dev->obj_md_name, sizeof(rbd_dev->obj_md_name), "%s%s", 2243 rbd_dev->obj, RBD_SUFFIX); 2244 2245 /* initialize rest of new object */ 2246 snprintf(rbd_dev->name, DEV_NAME_LEN, DRV_NAME "%d", rbd_dev->id); 2247 rc = rbd_get_client(rbd_dev, mon_dev_name, options); 2248 if (rc < 0) 2249 goto err_out_slot; 2250 2251 mutex_unlock(&ctl_mutex); 2252 2253 /* pick the pool */ 2254 osdc = &rbd_dev->client->osdc; 2255 rc = ceph_pg_poolid_by_name(osdc->osdmap, rbd_dev->pool_name); 2256 if (rc < 0) 2257 goto err_out_client; 2258 rbd_dev->poolid = rc; 2259 2260 /* register our block device */ 2261 irc = register_blkdev(0, rbd_dev->name); 2262 if (irc < 0) { 2263 rc = irc; 2264 goto err_out_client; 2265 } 2266 rbd_dev->major = irc; 2267 2268 rc = rbd_bus_add_dev(rbd_dev); 2269 if (rc) 2270 goto err_out_blkdev; 2271 2272 /* set up and announce blkdev mapping */ 2273 rc = rbd_init_disk(rbd_dev); 2274 if (rc) 2275 goto err_out_bus; 2276 2277 rc = rbd_init_watch_dev(rbd_dev); 2278 if (rc) 2279 goto err_out_bus; 2280 2281 return count; 2282 2283 err_out_bus: 2284 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 2285 list_del_init(&rbd_dev->node); 2286 mutex_unlock(&ctl_mutex); 2287 2288 /* this will also clean up rest of rbd_dev stuff */ 2289 2290 rbd_bus_del_dev(rbd_dev); 2291 kfree(options); 2292 kfree(mon_dev_name); 2293 return rc; 2294 2295 err_out_blkdev: 2296 unregister_blkdev(rbd_dev->major, rbd_dev->name); 2297 err_out_client: 2298 rbd_put_client(rbd_dev); 2299 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 2300 err_out_slot: 2301 list_del_init(&rbd_dev->node); 2302 mutex_unlock(&ctl_mutex); 2303 2304 kfree(rbd_dev); 2305 err_out_opt: 2306 kfree(options); 2307 err_mon_dev: 2308 kfree(mon_dev_name); 2309 err_out_mod: 2310 dout("Error adding device %s\n", buf); 2311 module_put(THIS_MODULE); 2312 return rc; 2313 } 2314 2315 static struct rbd_device *__rbd_get_dev(unsigned long id) 2316 { 2317 struct list_head *tmp; 2318 struct rbd_device *rbd_dev; 2319 2320 list_for_each(tmp, &rbd_dev_list) { 2321 rbd_dev = list_entry(tmp, struct rbd_device, node); 2322 if (rbd_dev->id == id) 2323 return rbd_dev; 2324 } 2325 return NULL; 2326 } 2327 2328 static void rbd_dev_release(struct device *dev) 2329 { 2330 struct rbd_device *rbd_dev = 2331 container_of(dev, struct rbd_device, dev); 2332 2333 if (rbd_dev->watch_request) 2334 ceph_osdc_unregister_linger_request(&rbd_dev->client->osdc, 2335 rbd_dev->watch_request); 2336 if (rbd_dev->watch_event) 2337 rbd_req_sync_unwatch(rbd_dev, rbd_dev->obj_md_name); 2338 2339 rbd_put_client(rbd_dev); 2340 2341 /* clean up and free blkdev */ 2342 rbd_free_disk(rbd_dev); 2343 unregister_blkdev(rbd_dev->major, rbd_dev->name); 2344 kfree(rbd_dev); 2345 2346 /* release module ref */ 2347 module_put(THIS_MODULE); 2348 } 2349 2350 static ssize_t rbd_remove(struct bus_type *bus, 2351 const char *buf, 2352 size_t count) 2353 { 2354 struct rbd_device *rbd_dev = NULL; 2355 int target_id, rc; 2356 unsigned long ul; 2357 int ret = count; 2358 2359 rc = strict_strtoul(buf, 10, &ul); 2360 if (rc) 2361 return rc; 2362 2363 /* convert to int; abort if we lost anything in the conversion */ 2364 target_id = (int) ul; 2365 if (target_id != ul) 2366 return -EINVAL; 2367 2368 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 2369 2370 rbd_dev = __rbd_get_dev(target_id); 2371 if (!rbd_dev) { 2372 ret = -ENOENT; 2373 goto done; 2374 } 2375 2376 list_del_init(&rbd_dev->node); 2377 2378 __rbd_remove_all_snaps(rbd_dev); 2379 rbd_bus_del_dev(rbd_dev); 2380 2381 done: 2382 mutex_unlock(&ctl_mutex); 2383 return ret; 2384 } 2385 2386 static ssize_t rbd_snap_add(struct device *dev, 2387 struct device_attribute *attr, 2388 const char *buf, 2389 size_t count) 2390 { 2391 struct rbd_device *rbd_dev = dev_to_rbd(dev); 2392 int ret; 2393 char *name = kmalloc(count + 1, GFP_KERNEL); 2394 if (!name) 2395 return -ENOMEM; 2396 2397 snprintf(name, count, "%s", buf); 2398 2399 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 2400 2401 ret = rbd_header_add_snap(rbd_dev, 2402 name, GFP_KERNEL); 2403 if (ret < 0) 2404 goto err_unlock; 2405 2406 ret = __rbd_update_snaps(rbd_dev); 2407 if (ret < 0) 2408 goto err_unlock; 2409 2410 /* shouldn't hold ctl_mutex when notifying.. notify might 2411 trigger a watch callback that would need to get that mutex */ 2412 mutex_unlock(&ctl_mutex); 2413 2414 /* make a best effort, don't error if failed */ 2415 rbd_req_sync_notify(rbd_dev, rbd_dev->obj_md_name); 2416 2417 ret = count; 2418 kfree(name); 2419 return ret; 2420 2421 err_unlock: 2422 mutex_unlock(&ctl_mutex); 2423 kfree(name); 2424 return ret; 2425 } 2426 2427 static ssize_t rbd_snap_rollback(struct device *dev, 2428 struct device_attribute *attr, 2429 const char *buf, 2430 size_t count) 2431 { 2432 struct rbd_device *rbd_dev = dev_to_rbd(dev); 2433 int ret; 2434 u64 snapid; 2435 u64 cur_ofs; 2436 char *seg_name = NULL; 2437 char *snap_name = kmalloc(count + 1, GFP_KERNEL); 2438 ret = -ENOMEM; 2439 if (!snap_name) 2440 return ret; 2441 2442 /* parse snaps add command */ 2443 snprintf(snap_name, count, "%s", buf); 2444 seg_name = kmalloc(RBD_MAX_SEG_NAME_LEN + 1, GFP_NOIO); 2445 if (!seg_name) 2446 goto done; 2447 2448 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING); 2449 2450 ret = snap_by_name(&rbd_dev->header, snap_name, &snapid, NULL); 2451 if (ret < 0) 2452 goto done_unlock; 2453 2454 dout("snapid=%lld\n", snapid); 2455 2456 cur_ofs = 0; 2457 while (cur_ofs < rbd_dev->header.image_size) { 2458 cur_ofs += rbd_get_segment(&rbd_dev->header, 2459 rbd_dev->obj, 2460 cur_ofs, (u64)-1, 2461 seg_name, NULL); 2462 dout("seg_name=%s\n", seg_name); 2463 2464 ret = rbd_req_sync_rollback_obj(rbd_dev, snapid, seg_name); 2465 if (ret < 0) 2466 pr_warning("could not roll back obj %s err=%d\n", 2467 seg_name, ret); 2468 } 2469 2470 ret = __rbd_update_snaps(rbd_dev); 2471 if (ret < 0) 2472 goto done_unlock; 2473 2474 ret = count; 2475 2476 done_unlock: 2477 mutex_unlock(&ctl_mutex); 2478 done: 2479 kfree(seg_name); 2480 kfree(snap_name); 2481 2482 return ret; 2483 } 2484 2485 static struct bus_attribute rbd_bus_attrs[] = { 2486 __ATTR(add, S_IWUSR, NULL, rbd_add), 2487 __ATTR(remove, S_IWUSR, NULL, rbd_remove), 2488 __ATTR_NULL 2489 }; 2490 2491 /* 2492 * create control files in sysfs 2493 * /sys/bus/rbd/... 2494 */ 2495 static int rbd_sysfs_init(void) 2496 { 2497 int ret; 2498 2499 rbd_bus_type.bus_attrs = rbd_bus_attrs; 2500 2501 ret = bus_register(&rbd_bus_type); 2502 if (ret < 0) 2503 return ret; 2504 2505 ret = device_register(&rbd_root_dev); 2506 2507 return ret; 2508 } 2509 2510 static void rbd_sysfs_cleanup(void) 2511 { 2512 device_unregister(&rbd_root_dev); 2513 bus_unregister(&rbd_bus_type); 2514 } 2515 2516 int __init rbd_init(void) 2517 { 2518 int rc; 2519 2520 rc = rbd_sysfs_init(); 2521 if (rc) 2522 return rc; 2523 spin_lock_init(&node_lock); 2524 pr_info("loaded " DRV_NAME_LONG "\n"); 2525 return 0; 2526 } 2527 2528 void __exit rbd_exit(void) 2529 { 2530 rbd_sysfs_cleanup(); 2531 } 2532 2533 module_init(rbd_init); 2534 module_exit(rbd_exit); 2535 2536 MODULE_AUTHOR("Sage Weil <sage@newdream.net>"); 2537 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>"); 2538 MODULE_DESCRIPTION("rados block device"); 2539 2540 /* following authorship retained from original osdblk.c */ 2541 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>"); 2542 2543 MODULE_LICENSE("GPL"); 2544