1 2 /* 3 rbd.c -- Export ceph rados objects as a Linux block device 4 5 6 based on drivers/block/osdblk.c: 7 8 Copyright 2009 Red Hat, Inc. 9 10 This program is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License as published by 12 the Free Software Foundation. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; see the file COPYING. If not, write to 21 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 22 23 24 25 For usage instructions, please refer to: 26 27 Documentation/ABI/testing/sysfs-bus-rbd 28 29 */ 30 31 #include <linux/ceph/libceph.h> 32 #include <linux/ceph/osd_client.h> 33 #include <linux/ceph/mon_client.h> 34 #include <linux/ceph/cls_lock_client.h> 35 #include <linux/ceph/striper.h> 36 #include <linux/ceph/decode.h> 37 #include <linux/parser.h> 38 #include <linux/bsearch.h> 39 40 #include <linux/kernel.h> 41 #include <linux/device.h> 42 #include <linux/module.h> 43 #include <linux/blk-mq.h> 44 #include <linux/fs.h> 45 #include <linux/blkdev.h> 46 #include <linux/slab.h> 47 #include <linux/idr.h> 48 #include <linux/workqueue.h> 49 50 #include "rbd_types.h" 51 52 #define RBD_DEBUG /* Activate rbd_assert() calls */ 53 54 /* 55 * Increment the given counter and return its updated value. 56 * If the counter is already 0 it will not be incremented. 57 * If the counter is already at its maximum value returns 58 * -EINVAL without updating it. 59 */ 60 static int atomic_inc_return_safe(atomic_t *v) 61 { 62 unsigned int counter; 63 64 counter = (unsigned int)atomic_fetch_add_unless(v, 1, 0); 65 if (counter <= (unsigned int)INT_MAX) 66 return (int)counter; 67 68 atomic_dec(v); 69 70 return -EINVAL; 71 } 72 73 /* Decrement the counter. Return the resulting value, or -EINVAL */ 74 static int atomic_dec_return_safe(atomic_t *v) 75 { 76 int counter; 77 78 counter = atomic_dec_return(v); 79 if (counter >= 0) 80 return counter; 81 82 atomic_inc(v); 83 84 return -EINVAL; 85 } 86 87 #define RBD_DRV_NAME "rbd" 88 89 #define RBD_MINORS_PER_MAJOR 256 90 #define RBD_SINGLE_MAJOR_PART_SHIFT 4 91 92 #define RBD_MAX_PARENT_CHAIN_LEN 16 93 94 #define RBD_SNAP_DEV_NAME_PREFIX "snap_" 95 #define RBD_MAX_SNAP_NAME_LEN \ 96 (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1)) 97 98 #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */ 99 100 #define RBD_SNAP_HEAD_NAME "-" 101 102 #define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */ 103 104 /* This allows a single page to hold an image name sent by OSD */ 105 #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1) 106 #define RBD_IMAGE_ID_LEN_MAX 64 107 108 #define RBD_OBJ_PREFIX_LEN_MAX 64 109 110 #define RBD_NOTIFY_TIMEOUT 5 /* seconds */ 111 #define RBD_RETRY_DELAY msecs_to_jiffies(1000) 112 113 /* Feature bits */ 114 115 #define RBD_FEATURE_LAYERING (1ULL<<0) 116 #define RBD_FEATURE_STRIPINGV2 (1ULL<<1) 117 #define RBD_FEATURE_EXCLUSIVE_LOCK (1ULL<<2) 118 #define RBD_FEATURE_DATA_POOL (1ULL<<7) 119 #define RBD_FEATURE_OPERATIONS (1ULL<<8) 120 121 #define RBD_FEATURES_ALL (RBD_FEATURE_LAYERING | \ 122 RBD_FEATURE_STRIPINGV2 | \ 123 RBD_FEATURE_EXCLUSIVE_LOCK | \ 124 RBD_FEATURE_DATA_POOL | \ 125 RBD_FEATURE_OPERATIONS) 126 127 /* Features supported by this (client software) implementation. */ 128 129 #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL) 130 131 /* 132 * An RBD device name will be "rbd#", where the "rbd" comes from 133 * RBD_DRV_NAME above, and # is a unique integer identifier. 134 */ 135 #define DEV_NAME_LEN 32 136 137 /* 138 * block device image metadata (in-memory version) 139 */ 140 struct rbd_image_header { 141 /* These six fields never change for a given rbd image */ 142 char *object_prefix; 143 __u8 obj_order; 144 u64 stripe_unit; 145 u64 stripe_count; 146 s64 data_pool_id; 147 u64 features; /* Might be changeable someday? */ 148 149 /* The remaining fields need to be updated occasionally */ 150 u64 image_size; 151 struct ceph_snap_context *snapc; 152 char *snap_names; /* format 1 only */ 153 u64 *snap_sizes; /* format 1 only */ 154 }; 155 156 /* 157 * An rbd image specification. 158 * 159 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely 160 * identify an image. Each rbd_dev structure includes a pointer to 161 * an rbd_spec structure that encapsulates this identity. 162 * 163 * Each of the id's in an rbd_spec has an associated name. For a 164 * user-mapped image, the names are supplied and the id's associated 165 * with them are looked up. For a layered image, a parent image is 166 * defined by the tuple, and the names are looked up. 167 * 168 * An rbd_dev structure contains a parent_spec pointer which is 169 * non-null if the image it represents is a child in a layered 170 * image. This pointer will refer to the rbd_spec structure used 171 * by the parent rbd_dev for its own identity (i.e., the structure 172 * is shared between the parent and child). 173 * 174 * Since these structures are populated once, during the discovery 175 * phase of image construction, they are effectively immutable so 176 * we make no effort to synchronize access to them. 177 * 178 * Note that code herein does not assume the image name is known (it 179 * could be a null pointer). 180 */ 181 struct rbd_spec { 182 u64 pool_id; 183 const char *pool_name; 184 const char *pool_ns; /* NULL if default, never "" */ 185 186 const char *image_id; 187 const char *image_name; 188 189 u64 snap_id; 190 const char *snap_name; 191 192 struct kref kref; 193 }; 194 195 /* 196 * an instance of the client. multiple devices may share an rbd client. 197 */ 198 struct rbd_client { 199 struct ceph_client *client; 200 struct kref kref; 201 struct list_head node; 202 }; 203 204 struct rbd_img_request; 205 206 enum obj_request_type { 207 OBJ_REQUEST_NODATA = 1, 208 OBJ_REQUEST_BIO, /* pointer into provided bio (list) */ 209 OBJ_REQUEST_BVECS, /* pointer into provided bio_vec array */ 210 OBJ_REQUEST_OWN_BVECS, /* private bio_vec array, doesn't own pages */ 211 }; 212 213 enum obj_operation_type { 214 OBJ_OP_READ = 1, 215 OBJ_OP_WRITE, 216 OBJ_OP_DISCARD, 217 }; 218 219 /* 220 * Writes go through the following state machine to deal with 221 * layering: 222 * 223 * need copyup 224 * RBD_OBJ_WRITE_GUARD ---------------> RBD_OBJ_WRITE_COPYUP 225 * | ^ | 226 * v \------------------------------/ 227 * done 228 * ^ 229 * | 230 * RBD_OBJ_WRITE_FLAT 231 * 232 * Writes start in RBD_OBJ_WRITE_GUARD or _FLAT, depending on whether 233 * there is a parent or not. 234 */ 235 enum rbd_obj_write_state { 236 RBD_OBJ_WRITE_FLAT = 1, 237 RBD_OBJ_WRITE_GUARD, 238 RBD_OBJ_WRITE_COPYUP, 239 }; 240 241 struct rbd_obj_request { 242 struct ceph_object_extent ex; 243 union { 244 bool tried_parent; /* for reads */ 245 enum rbd_obj_write_state write_state; /* for writes */ 246 }; 247 248 struct rbd_img_request *img_request; 249 struct ceph_file_extent *img_extents; 250 u32 num_img_extents; 251 252 union { 253 struct ceph_bio_iter bio_pos; 254 struct { 255 struct ceph_bvec_iter bvec_pos; 256 u32 bvec_count; 257 u32 bvec_idx; 258 }; 259 }; 260 struct bio_vec *copyup_bvecs; 261 u32 copyup_bvec_count; 262 263 struct ceph_osd_request *osd_req; 264 265 u64 xferred; /* bytes transferred */ 266 int result; 267 268 struct kref kref; 269 }; 270 271 enum img_req_flags { 272 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */ 273 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */ 274 }; 275 276 struct rbd_img_request { 277 struct rbd_device *rbd_dev; 278 enum obj_operation_type op_type; 279 enum obj_request_type data_type; 280 unsigned long flags; 281 union { 282 u64 snap_id; /* for reads */ 283 struct ceph_snap_context *snapc; /* for writes */ 284 }; 285 union { 286 struct request *rq; /* block request */ 287 struct rbd_obj_request *obj_request; /* obj req initiator */ 288 }; 289 spinlock_t completion_lock; 290 u64 xferred;/* aggregate bytes transferred */ 291 int result; /* first nonzero obj_request result */ 292 293 struct list_head object_extents; /* obj_req.ex structs */ 294 u32 obj_request_count; 295 u32 pending_count; 296 297 struct kref kref; 298 }; 299 300 #define for_each_obj_request(ireq, oreq) \ 301 list_for_each_entry(oreq, &(ireq)->object_extents, ex.oe_item) 302 #define for_each_obj_request_safe(ireq, oreq, n) \ 303 list_for_each_entry_safe(oreq, n, &(ireq)->object_extents, ex.oe_item) 304 305 enum rbd_watch_state { 306 RBD_WATCH_STATE_UNREGISTERED, 307 RBD_WATCH_STATE_REGISTERED, 308 RBD_WATCH_STATE_ERROR, 309 }; 310 311 enum rbd_lock_state { 312 RBD_LOCK_STATE_UNLOCKED, 313 RBD_LOCK_STATE_LOCKED, 314 RBD_LOCK_STATE_RELEASING, 315 }; 316 317 /* WatchNotify::ClientId */ 318 struct rbd_client_id { 319 u64 gid; 320 u64 handle; 321 }; 322 323 struct rbd_mapping { 324 u64 size; 325 u64 features; 326 }; 327 328 /* 329 * a single device 330 */ 331 struct rbd_device { 332 int dev_id; /* blkdev unique id */ 333 334 int major; /* blkdev assigned major */ 335 int minor; 336 struct gendisk *disk; /* blkdev's gendisk and rq */ 337 338 u32 image_format; /* Either 1 or 2 */ 339 struct rbd_client *rbd_client; 340 341 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */ 342 343 spinlock_t lock; /* queue, flags, open_count */ 344 345 struct rbd_image_header header; 346 unsigned long flags; /* possibly lock protected */ 347 struct rbd_spec *spec; 348 struct rbd_options *opts; 349 char *config_info; /* add{,_single_major} string */ 350 351 struct ceph_object_id header_oid; 352 struct ceph_object_locator header_oloc; 353 354 struct ceph_file_layout layout; /* used for all rbd requests */ 355 356 struct mutex watch_mutex; 357 enum rbd_watch_state watch_state; 358 struct ceph_osd_linger_request *watch_handle; 359 u64 watch_cookie; 360 struct delayed_work watch_dwork; 361 362 struct rw_semaphore lock_rwsem; 363 enum rbd_lock_state lock_state; 364 char lock_cookie[32]; 365 struct rbd_client_id owner_cid; 366 struct work_struct acquired_lock_work; 367 struct work_struct released_lock_work; 368 struct delayed_work lock_dwork; 369 struct work_struct unlock_work; 370 wait_queue_head_t lock_waitq; 371 372 struct workqueue_struct *task_wq; 373 374 struct rbd_spec *parent_spec; 375 u64 parent_overlap; 376 atomic_t parent_ref; 377 struct rbd_device *parent; 378 379 /* Block layer tags. */ 380 struct blk_mq_tag_set tag_set; 381 382 /* protects updating the header */ 383 struct rw_semaphore header_rwsem; 384 385 struct rbd_mapping mapping; 386 387 struct list_head node; 388 389 /* sysfs related */ 390 struct device dev; 391 unsigned long open_count; /* protected by lock */ 392 }; 393 394 /* 395 * Flag bits for rbd_dev->flags: 396 * - REMOVING (which is coupled with rbd_dev->open_count) is protected 397 * by rbd_dev->lock 398 * - BLACKLISTED is protected by rbd_dev->lock_rwsem 399 */ 400 enum rbd_dev_flags { 401 RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */ 402 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */ 403 RBD_DEV_FLAG_BLACKLISTED, /* our ceph_client is blacklisted */ 404 }; 405 406 static DEFINE_MUTEX(client_mutex); /* Serialize client creation */ 407 408 static LIST_HEAD(rbd_dev_list); /* devices */ 409 static DEFINE_SPINLOCK(rbd_dev_list_lock); 410 411 static LIST_HEAD(rbd_client_list); /* clients */ 412 static DEFINE_SPINLOCK(rbd_client_list_lock); 413 414 /* Slab caches for frequently-allocated structures */ 415 416 static struct kmem_cache *rbd_img_request_cache; 417 static struct kmem_cache *rbd_obj_request_cache; 418 419 static int rbd_major; 420 static DEFINE_IDA(rbd_dev_id_ida); 421 422 static struct workqueue_struct *rbd_wq; 423 424 /* 425 * single-major requires >= 0.75 version of userspace rbd utility. 426 */ 427 static bool single_major = true; 428 module_param(single_major, bool, 0444); 429 MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: true)"); 430 431 static ssize_t rbd_add(struct bus_type *bus, const char *buf, 432 size_t count); 433 static ssize_t rbd_remove(struct bus_type *bus, const char *buf, 434 size_t count); 435 static ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf, 436 size_t count); 437 static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf, 438 size_t count); 439 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth); 440 441 static int rbd_dev_id_to_minor(int dev_id) 442 { 443 return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT; 444 } 445 446 static int minor_to_rbd_dev_id(int minor) 447 { 448 return minor >> RBD_SINGLE_MAJOR_PART_SHIFT; 449 } 450 451 static bool __rbd_is_lock_owner(struct rbd_device *rbd_dev) 452 { 453 return rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED || 454 rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING; 455 } 456 457 static bool rbd_is_lock_owner(struct rbd_device *rbd_dev) 458 { 459 bool is_lock_owner; 460 461 down_read(&rbd_dev->lock_rwsem); 462 is_lock_owner = __rbd_is_lock_owner(rbd_dev); 463 up_read(&rbd_dev->lock_rwsem); 464 return is_lock_owner; 465 } 466 467 static ssize_t rbd_supported_features_show(struct bus_type *bus, char *buf) 468 { 469 return sprintf(buf, "0x%llx\n", RBD_FEATURES_SUPPORTED); 470 } 471 472 static BUS_ATTR(add, 0200, NULL, rbd_add); 473 static BUS_ATTR(remove, 0200, NULL, rbd_remove); 474 static BUS_ATTR(add_single_major, 0200, NULL, rbd_add_single_major); 475 static BUS_ATTR(remove_single_major, 0200, NULL, rbd_remove_single_major); 476 static BUS_ATTR(supported_features, 0444, rbd_supported_features_show, NULL); 477 478 static struct attribute *rbd_bus_attrs[] = { 479 &bus_attr_add.attr, 480 &bus_attr_remove.attr, 481 &bus_attr_add_single_major.attr, 482 &bus_attr_remove_single_major.attr, 483 &bus_attr_supported_features.attr, 484 NULL, 485 }; 486 487 static umode_t rbd_bus_is_visible(struct kobject *kobj, 488 struct attribute *attr, int index) 489 { 490 if (!single_major && 491 (attr == &bus_attr_add_single_major.attr || 492 attr == &bus_attr_remove_single_major.attr)) 493 return 0; 494 495 return attr->mode; 496 } 497 498 static const struct attribute_group rbd_bus_group = { 499 .attrs = rbd_bus_attrs, 500 .is_visible = rbd_bus_is_visible, 501 }; 502 __ATTRIBUTE_GROUPS(rbd_bus); 503 504 static struct bus_type rbd_bus_type = { 505 .name = "rbd", 506 .bus_groups = rbd_bus_groups, 507 }; 508 509 static void rbd_root_dev_release(struct device *dev) 510 { 511 } 512 513 static struct device rbd_root_dev = { 514 .init_name = "rbd", 515 .release = rbd_root_dev_release, 516 }; 517 518 static __printf(2, 3) 519 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...) 520 { 521 struct va_format vaf; 522 va_list args; 523 524 va_start(args, fmt); 525 vaf.fmt = fmt; 526 vaf.va = &args; 527 528 if (!rbd_dev) 529 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf); 530 else if (rbd_dev->disk) 531 printk(KERN_WARNING "%s: %s: %pV\n", 532 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf); 533 else if (rbd_dev->spec && rbd_dev->spec->image_name) 534 printk(KERN_WARNING "%s: image %s: %pV\n", 535 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf); 536 else if (rbd_dev->spec && rbd_dev->spec->image_id) 537 printk(KERN_WARNING "%s: id %s: %pV\n", 538 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf); 539 else /* punt */ 540 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n", 541 RBD_DRV_NAME, rbd_dev, &vaf); 542 va_end(args); 543 } 544 545 #ifdef RBD_DEBUG 546 #define rbd_assert(expr) \ 547 if (unlikely(!(expr))) { \ 548 printk(KERN_ERR "\nAssertion failure in %s() " \ 549 "at line %d:\n\n" \ 550 "\trbd_assert(%s);\n\n", \ 551 __func__, __LINE__, #expr); \ 552 BUG(); \ 553 } 554 #else /* !RBD_DEBUG */ 555 # define rbd_assert(expr) ((void) 0) 556 #endif /* !RBD_DEBUG */ 557 558 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev); 559 560 static int rbd_dev_refresh(struct rbd_device *rbd_dev); 561 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev); 562 static int rbd_dev_header_info(struct rbd_device *rbd_dev); 563 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev); 564 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, 565 u64 snap_id); 566 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 567 u8 *order, u64 *snap_size); 568 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, 569 u64 *snap_features); 570 571 static int rbd_open(struct block_device *bdev, fmode_t mode) 572 { 573 struct rbd_device *rbd_dev = bdev->bd_disk->private_data; 574 bool removing = false; 575 576 spin_lock_irq(&rbd_dev->lock); 577 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) 578 removing = true; 579 else 580 rbd_dev->open_count++; 581 spin_unlock_irq(&rbd_dev->lock); 582 if (removing) 583 return -ENOENT; 584 585 (void) get_device(&rbd_dev->dev); 586 587 return 0; 588 } 589 590 static void rbd_release(struct gendisk *disk, fmode_t mode) 591 { 592 struct rbd_device *rbd_dev = disk->private_data; 593 unsigned long open_count_before; 594 595 spin_lock_irq(&rbd_dev->lock); 596 open_count_before = rbd_dev->open_count--; 597 spin_unlock_irq(&rbd_dev->lock); 598 rbd_assert(open_count_before > 0); 599 600 put_device(&rbd_dev->dev); 601 } 602 603 static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg) 604 { 605 int ro; 606 607 if (get_user(ro, (int __user *)arg)) 608 return -EFAULT; 609 610 /* Snapshots can't be marked read-write */ 611 if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro) 612 return -EROFS; 613 614 /* Let blkdev_roset() handle it */ 615 return -ENOTTY; 616 } 617 618 static int rbd_ioctl(struct block_device *bdev, fmode_t mode, 619 unsigned int cmd, unsigned long arg) 620 { 621 struct rbd_device *rbd_dev = bdev->bd_disk->private_data; 622 int ret; 623 624 switch (cmd) { 625 case BLKROSET: 626 ret = rbd_ioctl_set_ro(rbd_dev, arg); 627 break; 628 default: 629 ret = -ENOTTY; 630 } 631 632 return ret; 633 } 634 635 #ifdef CONFIG_COMPAT 636 static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode, 637 unsigned int cmd, unsigned long arg) 638 { 639 return rbd_ioctl(bdev, mode, cmd, arg); 640 } 641 #endif /* CONFIG_COMPAT */ 642 643 static const struct block_device_operations rbd_bd_ops = { 644 .owner = THIS_MODULE, 645 .open = rbd_open, 646 .release = rbd_release, 647 .ioctl = rbd_ioctl, 648 #ifdef CONFIG_COMPAT 649 .compat_ioctl = rbd_compat_ioctl, 650 #endif 651 }; 652 653 /* 654 * Initialize an rbd client instance. Success or not, this function 655 * consumes ceph_opts. Caller holds client_mutex. 656 */ 657 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts) 658 { 659 struct rbd_client *rbdc; 660 int ret = -ENOMEM; 661 662 dout("%s:\n", __func__); 663 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL); 664 if (!rbdc) 665 goto out_opt; 666 667 kref_init(&rbdc->kref); 668 INIT_LIST_HEAD(&rbdc->node); 669 670 rbdc->client = ceph_create_client(ceph_opts, rbdc); 671 if (IS_ERR(rbdc->client)) 672 goto out_rbdc; 673 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */ 674 675 ret = ceph_open_session(rbdc->client); 676 if (ret < 0) 677 goto out_client; 678 679 spin_lock(&rbd_client_list_lock); 680 list_add_tail(&rbdc->node, &rbd_client_list); 681 spin_unlock(&rbd_client_list_lock); 682 683 dout("%s: rbdc %p\n", __func__, rbdc); 684 685 return rbdc; 686 out_client: 687 ceph_destroy_client(rbdc->client); 688 out_rbdc: 689 kfree(rbdc); 690 out_opt: 691 if (ceph_opts) 692 ceph_destroy_options(ceph_opts); 693 dout("%s: error %d\n", __func__, ret); 694 695 return ERR_PTR(ret); 696 } 697 698 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc) 699 { 700 kref_get(&rbdc->kref); 701 702 return rbdc; 703 } 704 705 /* 706 * Find a ceph client with specific addr and configuration. If 707 * found, bump its reference count. 708 */ 709 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts) 710 { 711 struct rbd_client *client_node; 712 bool found = false; 713 714 if (ceph_opts->flags & CEPH_OPT_NOSHARE) 715 return NULL; 716 717 spin_lock(&rbd_client_list_lock); 718 list_for_each_entry(client_node, &rbd_client_list, node) { 719 if (!ceph_compare_options(ceph_opts, client_node->client)) { 720 __rbd_get_client(client_node); 721 722 found = true; 723 break; 724 } 725 } 726 spin_unlock(&rbd_client_list_lock); 727 728 return found ? client_node : NULL; 729 } 730 731 /* 732 * (Per device) rbd map options 733 */ 734 enum { 735 Opt_queue_depth, 736 Opt_lock_timeout, 737 Opt_last_int, 738 /* int args above */ 739 Opt_pool_ns, 740 Opt_last_string, 741 /* string args above */ 742 Opt_read_only, 743 Opt_read_write, 744 Opt_lock_on_read, 745 Opt_exclusive, 746 Opt_notrim, 747 Opt_err 748 }; 749 750 static match_table_t rbd_opts_tokens = { 751 {Opt_queue_depth, "queue_depth=%d"}, 752 {Opt_lock_timeout, "lock_timeout=%d"}, 753 /* int args above */ 754 {Opt_pool_ns, "_pool_ns=%s"}, 755 /* string args above */ 756 {Opt_read_only, "read_only"}, 757 {Opt_read_only, "ro"}, /* Alternate spelling */ 758 {Opt_read_write, "read_write"}, 759 {Opt_read_write, "rw"}, /* Alternate spelling */ 760 {Opt_lock_on_read, "lock_on_read"}, 761 {Opt_exclusive, "exclusive"}, 762 {Opt_notrim, "notrim"}, 763 {Opt_err, NULL} 764 }; 765 766 struct rbd_options { 767 int queue_depth; 768 unsigned long lock_timeout; 769 bool read_only; 770 bool lock_on_read; 771 bool exclusive; 772 bool trim; 773 }; 774 775 #define RBD_QUEUE_DEPTH_DEFAULT BLKDEV_MAX_RQ 776 #define RBD_LOCK_TIMEOUT_DEFAULT 0 /* no timeout */ 777 #define RBD_READ_ONLY_DEFAULT false 778 #define RBD_LOCK_ON_READ_DEFAULT false 779 #define RBD_EXCLUSIVE_DEFAULT false 780 #define RBD_TRIM_DEFAULT true 781 782 struct parse_rbd_opts_ctx { 783 struct rbd_spec *spec; 784 struct rbd_options *opts; 785 }; 786 787 static int parse_rbd_opts_token(char *c, void *private) 788 { 789 struct parse_rbd_opts_ctx *pctx = private; 790 substring_t argstr[MAX_OPT_ARGS]; 791 int token, intval, ret; 792 793 token = match_token(c, rbd_opts_tokens, argstr); 794 if (token < Opt_last_int) { 795 ret = match_int(&argstr[0], &intval); 796 if (ret < 0) { 797 pr_err("bad option arg (not int) at '%s'\n", c); 798 return ret; 799 } 800 dout("got int token %d val %d\n", token, intval); 801 } else if (token > Opt_last_int && token < Opt_last_string) { 802 dout("got string token %d val %s\n", token, argstr[0].from); 803 } else { 804 dout("got token %d\n", token); 805 } 806 807 switch (token) { 808 case Opt_queue_depth: 809 if (intval < 1) { 810 pr_err("queue_depth out of range\n"); 811 return -EINVAL; 812 } 813 pctx->opts->queue_depth = intval; 814 break; 815 case Opt_lock_timeout: 816 /* 0 is "wait forever" (i.e. infinite timeout) */ 817 if (intval < 0 || intval > INT_MAX / 1000) { 818 pr_err("lock_timeout out of range\n"); 819 return -EINVAL; 820 } 821 pctx->opts->lock_timeout = msecs_to_jiffies(intval * 1000); 822 break; 823 case Opt_pool_ns: 824 kfree(pctx->spec->pool_ns); 825 pctx->spec->pool_ns = match_strdup(argstr); 826 if (!pctx->spec->pool_ns) 827 return -ENOMEM; 828 break; 829 case Opt_read_only: 830 pctx->opts->read_only = true; 831 break; 832 case Opt_read_write: 833 pctx->opts->read_only = false; 834 break; 835 case Opt_lock_on_read: 836 pctx->opts->lock_on_read = true; 837 break; 838 case Opt_exclusive: 839 pctx->opts->exclusive = true; 840 break; 841 case Opt_notrim: 842 pctx->opts->trim = false; 843 break; 844 default: 845 /* libceph prints "bad option" msg */ 846 return -EINVAL; 847 } 848 849 return 0; 850 } 851 852 static char* obj_op_name(enum obj_operation_type op_type) 853 { 854 switch (op_type) { 855 case OBJ_OP_READ: 856 return "read"; 857 case OBJ_OP_WRITE: 858 return "write"; 859 case OBJ_OP_DISCARD: 860 return "discard"; 861 default: 862 return "???"; 863 } 864 } 865 866 /* 867 * Destroy ceph client 868 * 869 * Caller must hold rbd_client_list_lock. 870 */ 871 static void rbd_client_release(struct kref *kref) 872 { 873 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref); 874 875 dout("%s: rbdc %p\n", __func__, rbdc); 876 spin_lock(&rbd_client_list_lock); 877 list_del(&rbdc->node); 878 spin_unlock(&rbd_client_list_lock); 879 880 ceph_destroy_client(rbdc->client); 881 kfree(rbdc); 882 } 883 884 /* 885 * Drop reference to ceph client node. If it's not referenced anymore, release 886 * it. 887 */ 888 static void rbd_put_client(struct rbd_client *rbdc) 889 { 890 if (rbdc) 891 kref_put(&rbdc->kref, rbd_client_release); 892 } 893 894 static int wait_for_latest_osdmap(struct ceph_client *client) 895 { 896 u64 newest_epoch; 897 int ret; 898 899 ret = ceph_monc_get_version(&client->monc, "osdmap", &newest_epoch); 900 if (ret) 901 return ret; 902 903 if (client->osdc.osdmap->epoch >= newest_epoch) 904 return 0; 905 906 ceph_osdc_maybe_request_map(&client->osdc); 907 return ceph_monc_wait_osdmap(&client->monc, newest_epoch, 908 client->options->mount_timeout); 909 } 910 911 /* 912 * Get a ceph client with specific addr and configuration, if one does 913 * not exist create it. Either way, ceph_opts is consumed by this 914 * function. 915 */ 916 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts) 917 { 918 struct rbd_client *rbdc; 919 int ret; 920 921 mutex_lock_nested(&client_mutex, SINGLE_DEPTH_NESTING); 922 rbdc = rbd_client_find(ceph_opts); 923 if (rbdc) { 924 ceph_destroy_options(ceph_opts); 925 926 /* 927 * Using an existing client. Make sure ->pg_pools is up to 928 * date before we look up the pool id in do_rbd_add(). 929 */ 930 ret = wait_for_latest_osdmap(rbdc->client); 931 if (ret) { 932 rbd_warn(NULL, "failed to get latest osdmap: %d", ret); 933 rbd_put_client(rbdc); 934 rbdc = ERR_PTR(ret); 935 } 936 } else { 937 rbdc = rbd_client_create(ceph_opts); 938 } 939 mutex_unlock(&client_mutex); 940 941 return rbdc; 942 } 943 944 static bool rbd_image_format_valid(u32 image_format) 945 { 946 return image_format == 1 || image_format == 2; 947 } 948 949 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk) 950 { 951 size_t size; 952 u32 snap_count; 953 954 /* The header has to start with the magic rbd header text */ 955 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT))) 956 return false; 957 958 /* The bio layer requires at least sector-sized I/O */ 959 960 if (ondisk->options.order < SECTOR_SHIFT) 961 return false; 962 963 /* If we use u64 in a few spots we may be able to loosen this */ 964 965 if (ondisk->options.order > 8 * sizeof (int) - 1) 966 return false; 967 968 /* 969 * The size of a snapshot header has to fit in a size_t, and 970 * that limits the number of snapshots. 971 */ 972 snap_count = le32_to_cpu(ondisk->snap_count); 973 size = SIZE_MAX - sizeof (struct ceph_snap_context); 974 if (snap_count > size / sizeof (__le64)) 975 return false; 976 977 /* 978 * Not only that, but the size of the entire the snapshot 979 * header must also be representable in a size_t. 980 */ 981 size -= snap_count * sizeof (__le64); 982 if ((u64) size < le64_to_cpu(ondisk->snap_names_len)) 983 return false; 984 985 return true; 986 } 987 988 /* 989 * returns the size of an object in the image 990 */ 991 static u32 rbd_obj_bytes(struct rbd_image_header *header) 992 { 993 return 1U << header->obj_order; 994 } 995 996 static void rbd_init_layout(struct rbd_device *rbd_dev) 997 { 998 if (rbd_dev->header.stripe_unit == 0 || 999 rbd_dev->header.stripe_count == 0) { 1000 rbd_dev->header.stripe_unit = rbd_obj_bytes(&rbd_dev->header); 1001 rbd_dev->header.stripe_count = 1; 1002 } 1003 1004 rbd_dev->layout.stripe_unit = rbd_dev->header.stripe_unit; 1005 rbd_dev->layout.stripe_count = rbd_dev->header.stripe_count; 1006 rbd_dev->layout.object_size = rbd_obj_bytes(&rbd_dev->header); 1007 rbd_dev->layout.pool_id = rbd_dev->header.data_pool_id == CEPH_NOPOOL ? 1008 rbd_dev->spec->pool_id : rbd_dev->header.data_pool_id; 1009 RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL); 1010 } 1011 1012 /* 1013 * Fill an rbd image header with information from the given format 1 1014 * on-disk header. 1015 */ 1016 static int rbd_header_from_disk(struct rbd_device *rbd_dev, 1017 struct rbd_image_header_ondisk *ondisk) 1018 { 1019 struct rbd_image_header *header = &rbd_dev->header; 1020 bool first_time = header->object_prefix == NULL; 1021 struct ceph_snap_context *snapc; 1022 char *object_prefix = NULL; 1023 char *snap_names = NULL; 1024 u64 *snap_sizes = NULL; 1025 u32 snap_count; 1026 int ret = -ENOMEM; 1027 u32 i; 1028 1029 /* Allocate this now to avoid having to handle failure below */ 1030 1031 if (first_time) { 1032 object_prefix = kstrndup(ondisk->object_prefix, 1033 sizeof(ondisk->object_prefix), 1034 GFP_KERNEL); 1035 if (!object_prefix) 1036 return -ENOMEM; 1037 } 1038 1039 /* Allocate the snapshot context and fill it in */ 1040 1041 snap_count = le32_to_cpu(ondisk->snap_count); 1042 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); 1043 if (!snapc) 1044 goto out_err; 1045 snapc->seq = le64_to_cpu(ondisk->snap_seq); 1046 if (snap_count) { 1047 struct rbd_image_snap_ondisk *snaps; 1048 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len); 1049 1050 /* We'll keep a copy of the snapshot names... */ 1051 1052 if (snap_names_len > (u64)SIZE_MAX) 1053 goto out_2big; 1054 snap_names = kmalloc(snap_names_len, GFP_KERNEL); 1055 if (!snap_names) 1056 goto out_err; 1057 1058 /* ...as well as the array of their sizes. */ 1059 snap_sizes = kmalloc_array(snap_count, 1060 sizeof(*header->snap_sizes), 1061 GFP_KERNEL); 1062 if (!snap_sizes) 1063 goto out_err; 1064 1065 /* 1066 * Copy the names, and fill in each snapshot's id 1067 * and size. 1068 * 1069 * Note that rbd_dev_v1_header_info() guarantees the 1070 * ondisk buffer we're working with has 1071 * snap_names_len bytes beyond the end of the 1072 * snapshot id array, this memcpy() is safe. 1073 */ 1074 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len); 1075 snaps = ondisk->snaps; 1076 for (i = 0; i < snap_count; i++) { 1077 snapc->snaps[i] = le64_to_cpu(snaps[i].id); 1078 snap_sizes[i] = le64_to_cpu(snaps[i].image_size); 1079 } 1080 } 1081 1082 /* We won't fail any more, fill in the header */ 1083 1084 if (first_time) { 1085 header->object_prefix = object_prefix; 1086 header->obj_order = ondisk->options.order; 1087 rbd_init_layout(rbd_dev); 1088 } else { 1089 ceph_put_snap_context(header->snapc); 1090 kfree(header->snap_names); 1091 kfree(header->snap_sizes); 1092 } 1093 1094 /* The remaining fields always get updated (when we refresh) */ 1095 1096 header->image_size = le64_to_cpu(ondisk->image_size); 1097 header->snapc = snapc; 1098 header->snap_names = snap_names; 1099 header->snap_sizes = snap_sizes; 1100 1101 return 0; 1102 out_2big: 1103 ret = -EIO; 1104 out_err: 1105 kfree(snap_sizes); 1106 kfree(snap_names); 1107 ceph_put_snap_context(snapc); 1108 kfree(object_prefix); 1109 1110 return ret; 1111 } 1112 1113 static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which) 1114 { 1115 const char *snap_name; 1116 1117 rbd_assert(which < rbd_dev->header.snapc->num_snaps); 1118 1119 /* Skip over names until we find the one we are looking for */ 1120 1121 snap_name = rbd_dev->header.snap_names; 1122 while (which--) 1123 snap_name += strlen(snap_name) + 1; 1124 1125 return kstrdup(snap_name, GFP_KERNEL); 1126 } 1127 1128 /* 1129 * Snapshot id comparison function for use with qsort()/bsearch(). 1130 * Note that result is for snapshots in *descending* order. 1131 */ 1132 static int snapid_compare_reverse(const void *s1, const void *s2) 1133 { 1134 u64 snap_id1 = *(u64 *)s1; 1135 u64 snap_id2 = *(u64 *)s2; 1136 1137 if (snap_id1 < snap_id2) 1138 return 1; 1139 return snap_id1 == snap_id2 ? 0 : -1; 1140 } 1141 1142 /* 1143 * Search a snapshot context to see if the given snapshot id is 1144 * present. 1145 * 1146 * Returns the position of the snapshot id in the array if it's found, 1147 * or BAD_SNAP_INDEX otherwise. 1148 * 1149 * Note: The snapshot array is in kept sorted (by the osd) in 1150 * reverse order, highest snapshot id first. 1151 */ 1152 static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id) 1153 { 1154 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 1155 u64 *found; 1156 1157 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps, 1158 sizeof (snap_id), snapid_compare_reverse); 1159 1160 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX; 1161 } 1162 1163 static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, 1164 u64 snap_id) 1165 { 1166 u32 which; 1167 const char *snap_name; 1168 1169 which = rbd_dev_snap_index(rbd_dev, snap_id); 1170 if (which == BAD_SNAP_INDEX) 1171 return ERR_PTR(-ENOENT); 1172 1173 snap_name = _rbd_dev_v1_snap_name(rbd_dev, which); 1174 return snap_name ? snap_name : ERR_PTR(-ENOMEM); 1175 } 1176 1177 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id) 1178 { 1179 if (snap_id == CEPH_NOSNAP) 1180 return RBD_SNAP_HEAD_NAME; 1181 1182 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 1183 if (rbd_dev->image_format == 1) 1184 return rbd_dev_v1_snap_name(rbd_dev, snap_id); 1185 1186 return rbd_dev_v2_snap_name(rbd_dev, snap_id); 1187 } 1188 1189 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 1190 u64 *snap_size) 1191 { 1192 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 1193 if (snap_id == CEPH_NOSNAP) { 1194 *snap_size = rbd_dev->header.image_size; 1195 } else if (rbd_dev->image_format == 1) { 1196 u32 which; 1197 1198 which = rbd_dev_snap_index(rbd_dev, snap_id); 1199 if (which == BAD_SNAP_INDEX) 1200 return -ENOENT; 1201 1202 *snap_size = rbd_dev->header.snap_sizes[which]; 1203 } else { 1204 u64 size = 0; 1205 int ret; 1206 1207 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size); 1208 if (ret) 1209 return ret; 1210 1211 *snap_size = size; 1212 } 1213 return 0; 1214 } 1215 1216 static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id, 1217 u64 *snap_features) 1218 { 1219 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 1220 if (snap_id == CEPH_NOSNAP) { 1221 *snap_features = rbd_dev->header.features; 1222 } else if (rbd_dev->image_format == 1) { 1223 *snap_features = 0; /* No features for format 1 */ 1224 } else { 1225 u64 features = 0; 1226 int ret; 1227 1228 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features); 1229 if (ret) 1230 return ret; 1231 1232 *snap_features = features; 1233 } 1234 return 0; 1235 } 1236 1237 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev) 1238 { 1239 u64 snap_id = rbd_dev->spec->snap_id; 1240 u64 size = 0; 1241 u64 features = 0; 1242 int ret; 1243 1244 ret = rbd_snap_size(rbd_dev, snap_id, &size); 1245 if (ret) 1246 return ret; 1247 ret = rbd_snap_features(rbd_dev, snap_id, &features); 1248 if (ret) 1249 return ret; 1250 1251 rbd_dev->mapping.size = size; 1252 rbd_dev->mapping.features = features; 1253 1254 return 0; 1255 } 1256 1257 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev) 1258 { 1259 rbd_dev->mapping.size = 0; 1260 rbd_dev->mapping.features = 0; 1261 } 1262 1263 static void zero_bvec(struct bio_vec *bv) 1264 { 1265 void *buf; 1266 unsigned long flags; 1267 1268 buf = bvec_kmap_irq(bv, &flags); 1269 memset(buf, 0, bv->bv_len); 1270 flush_dcache_page(bv->bv_page); 1271 bvec_kunmap_irq(buf, &flags); 1272 } 1273 1274 static void zero_bios(struct ceph_bio_iter *bio_pos, u32 off, u32 bytes) 1275 { 1276 struct ceph_bio_iter it = *bio_pos; 1277 1278 ceph_bio_iter_advance(&it, off); 1279 ceph_bio_iter_advance_step(&it, bytes, ({ 1280 zero_bvec(&bv); 1281 })); 1282 } 1283 1284 static void zero_bvecs(struct ceph_bvec_iter *bvec_pos, u32 off, u32 bytes) 1285 { 1286 struct ceph_bvec_iter it = *bvec_pos; 1287 1288 ceph_bvec_iter_advance(&it, off); 1289 ceph_bvec_iter_advance_step(&it, bytes, ({ 1290 zero_bvec(&bv); 1291 })); 1292 } 1293 1294 /* 1295 * Zero a range in @obj_req data buffer defined by a bio (list) or 1296 * (private) bio_vec array. 1297 * 1298 * @off is relative to the start of the data buffer. 1299 */ 1300 static void rbd_obj_zero_range(struct rbd_obj_request *obj_req, u32 off, 1301 u32 bytes) 1302 { 1303 switch (obj_req->img_request->data_type) { 1304 case OBJ_REQUEST_BIO: 1305 zero_bios(&obj_req->bio_pos, off, bytes); 1306 break; 1307 case OBJ_REQUEST_BVECS: 1308 case OBJ_REQUEST_OWN_BVECS: 1309 zero_bvecs(&obj_req->bvec_pos, off, bytes); 1310 break; 1311 default: 1312 rbd_assert(0); 1313 } 1314 } 1315 1316 static void rbd_obj_request_destroy(struct kref *kref); 1317 static void rbd_obj_request_put(struct rbd_obj_request *obj_request) 1318 { 1319 rbd_assert(obj_request != NULL); 1320 dout("%s: obj %p (was %d)\n", __func__, obj_request, 1321 kref_read(&obj_request->kref)); 1322 kref_put(&obj_request->kref, rbd_obj_request_destroy); 1323 } 1324 1325 static void rbd_img_request_get(struct rbd_img_request *img_request) 1326 { 1327 dout("%s: img %p (was %d)\n", __func__, img_request, 1328 kref_read(&img_request->kref)); 1329 kref_get(&img_request->kref); 1330 } 1331 1332 static void rbd_img_request_destroy(struct kref *kref); 1333 static void rbd_img_request_put(struct rbd_img_request *img_request) 1334 { 1335 rbd_assert(img_request != NULL); 1336 dout("%s: img %p (was %d)\n", __func__, img_request, 1337 kref_read(&img_request->kref)); 1338 kref_put(&img_request->kref, rbd_img_request_destroy); 1339 } 1340 1341 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request, 1342 struct rbd_obj_request *obj_request) 1343 { 1344 rbd_assert(obj_request->img_request == NULL); 1345 1346 /* Image request now owns object's original reference */ 1347 obj_request->img_request = img_request; 1348 img_request->obj_request_count++; 1349 img_request->pending_count++; 1350 dout("%s: img %p obj %p\n", __func__, img_request, obj_request); 1351 } 1352 1353 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request, 1354 struct rbd_obj_request *obj_request) 1355 { 1356 dout("%s: img %p obj %p\n", __func__, img_request, obj_request); 1357 list_del(&obj_request->ex.oe_item); 1358 rbd_assert(img_request->obj_request_count > 0); 1359 img_request->obj_request_count--; 1360 rbd_assert(obj_request->img_request == img_request); 1361 rbd_obj_request_put(obj_request); 1362 } 1363 1364 static void rbd_obj_request_submit(struct rbd_obj_request *obj_request) 1365 { 1366 struct ceph_osd_request *osd_req = obj_request->osd_req; 1367 1368 dout("%s %p object_no %016llx %llu~%llu osd_req %p\n", __func__, 1369 obj_request, obj_request->ex.oe_objno, obj_request->ex.oe_off, 1370 obj_request->ex.oe_len, osd_req); 1371 ceph_osdc_start_request(osd_req->r_osdc, osd_req, false); 1372 } 1373 1374 /* 1375 * The default/initial value for all image request flags is 0. Each 1376 * is conditionally set to 1 at image request initialization time 1377 * and currently never change thereafter. 1378 */ 1379 static void img_request_layered_set(struct rbd_img_request *img_request) 1380 { 1381 set_bit(IMG_REQ_LAYERED, &img_request->flags); 1382 smp_mb(); 1383 } 1384 1385 static void img_request_layered_clear(struct rbd_img_request *img_request) 1386 { 1387 clear_bit(IMG_REQ_LAYERED, &img_request->flags); 1388 smp_mb(); 1389 } 1390 1391 static bool img_request_layered_test(struct rbd_img_request *img_request) 1392 { 1393 smp_mb(); 1394 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0; 1395 } 1396 1397 static bool rbd_obj_is_entire(struct rbd_obj_request *obj_req) 1398 { 1399 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 1400 1401 return !obj_req->ex.oe_off && 1402 obj_req->ex.oe_len == rbd_dev->layout.object_size; 1403 } 1404 1405 static bool rbd_obj_is_tail(struct rbd_obj_request *obj_req) 1406 { 1407 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 1408 1409 return obj_req->ex.oe_off + obj_req->ex.oe_len == 1410 rbd_dev->layout.object_size; 1411 } 1412 1413 static u64 rbd_obj_img_extents_bytes(struct rbd_obj_request *obj_req) 1414 { 1415 return ceph_file_extents_bytes(obj_req->img_extents, 1416 obj_req->num_img_extents); 1417 } 1418 1419 static bool rbd_img_is_write(struct rbd_img_request *img_req) 1420 { 1421 switch (img_req->op_type) { 1422 case OBJ_OP_READ: 1423 return false; 1424 case OBJ_OP_WRITE: 1425 case OBJ_OP_DISCARD: 1426 return true; 1427 default: 1428 BUG(); 1429 } 1430 } 1431 1432 static void rbd_obj_handle_request(struct rbd_obj_request *obj_req); 1433 1434 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req) 1435 { 1436 struct rbd_obj_request *obj_req = osd_req->r_priv; 1437 1438 dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req, 1439 osd_req->r_result, obj_req); 1440 rbd_assert(osd_req == obj_req->osd_req); 1441 1442 obj_req->result = osd_req->r_result < 0 ? osd_req->r_result : 0; 1443 if (!obj_req->result && !rbd_img_is_write(obj_req->img_request)) 1444 obj_req->xferred = osd_req->r_result; 1445 else 1446 /* 1447 * Writes aren't allowed to return a data payload. In some 1448 * guarded write cases (e.g. stat + zero on an empty object) 1449 * a stat response makes it through, but we don't care. 1450 */ 1451 obj_req->xferred = 0; 1452 1453 rbd_obj_handle_request(obj_req); 1454 } 1455 1456 static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request) 1457 { 1458 struct ceph_osd_request *osd_req = obj_request->osd_req; 1459 1460 osd_req->r_flags = CEPH_OSD_FLAG_READ; 1461 osd_req->r_snapid = obj_request->img_request->snap_id; 1462 } 1463 1464 static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request) 1465 { 1466 struct ceph_osd_request *osd_req = obj_request->osd_req; 1467 1468 osd_req->r_flags = CEPH_OSD_FLAG_WRITE; 1469 ktime_get_real_ts64(&osd_req->r_mtime); 1470 osd_req->r_data_offset = obj_request->ex.oe_off; 1471 } 1472 1473 static struct ceph_osd_request * 1474 rbd_osd_req_create(struct rbd_obj_request *obj_req, unsigned int num_ops) 1475 { 1476 struct rbd_img_request *img_req = obj_req->img_request; 1477 struct rbd_device *rbd_dev = img_req->rbd_dev; 1478 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 1479 struct ceph_osd_request *req; 1480 const char *name_format = rbd_dev->image_format == 1 ? 1481 RBD_V1_DATA_FORMAT : RBD_V2_DATA_FORMAT; 1482 1483 req = ceph_osdc_alloc_request(osdc, 1484 (rbd_img_is_write(img_req) ? img_req->snapc : NULL), 1485 num_ops, false, GFP_NOIO); 1486 if (!req) 1487 return NULL; 1488 1489 req->r_callback = rbd_osd_req_callback; 1490 req->r_priv = obj_req; 1491 1492 /* 1493 * Data objects may be stored in a separate pool, but always in 1494 * the same namespace in that pool as the header in its pool. 1495 */ 1496 ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc); 1497 req->r_base_oloc.pool = rbd_dev->layout.pool_id; 1498 1499 if (ceph_oid_aprintf(&req->r_base_oid, GFP_NOIO, name_format, 1500 rbd_dev->header.object_prefix, obj_req->ex.oe_objno)) 1501 goto err_req; 1502 1503 return req; 1504 1505 err_req: 1506 ceph_osdc_put_request(req); 1507 return NULL; 1508 } 1509 1510 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req) 1511 { 1512 ceph_osdc_put_request(osd_req); 1513 } 1514 1515 static struct rbd_obj_request *rbd_obj_request_create(void) 1516 { 1517 struct rbd_obj_request *obj_request; 1518 1519 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO); 1520 if (!obj_request) 1521 return NULL; 1522 1523 ceph_object_extent_init(&obj_request->ex); 1524 kref_init(&obj_request->kref); 1525 1526 dout("%s %p\n", __func__, obj_request); 1527 return obj_request; 1528 } 1529 1530 static void rbd_obj_request_destroy(struct kref *kref) 1531 { 1532 struct rbd_obj_request *obj_request; 1533 u32 i; 1534 1535 obj_request = container_of(kref, struct rbd_obj_request, kref); 1536 1537 dout("%s: obj %p\n", __func__, obj_request); 1538 1539 if (obj_request->osd_req) 1540 rbd_osd_req_destroy(obj_request->osd_req); 1541 1542 switch (obj_request->img_request->data_type) { 1543 case OBJ_REQUEST_NODATA: 1544 case OBJ_REQUEST_BIO: 1545 case OBJ_REQUEST_BVECS: 1546 break; /* Nothing to do */ 1547 case OBJ_REQUEST_OWN_BVECS: 1548 kfree(obj_request->bvec_pos.bvecs); 1549 break; 1550 default: 1551 rbd_assert(0); 1552 } 1553 1554 kfree(obj_request->img_extents); 1555 if (obj_request->copyup_bvecs) { 1556 for (i = 0; i < obj_request->copyup_bvec_count; i++) { 1557 if (obj_request->copyup_bvecs[i].bv_page) 1558 __free_page(obj_request->copyup_bvecs[i].bv_page); 1559 } 1560 kfree(obj_request->copyup_bvecs); 1561 } 1562 1563 kmem_cache_free(rbd_obj_request_cache, obj_request); 1564 } 1565 1566 /* It's OK to call this for a device with no parent */ 1567 1568 static void rbd_spec_put(struct rbd_spec *spec); 1569 static void rbd_dev_unparent(struct rbd_device *rbd_dev) 1570 { 1571 rbd_dev_remove_parent(rbd_dev); 1572 rbd_spec_put(rbd_dev->parent_spec); 1573 rbd_dev->parent_spec = NULL; 1574 rbd_dev->parent_overlap = 0; 1575 } 1576 1577 /* 1578 * Parent image reference counting is used to determine when an 1579 * image's parent fields can be safely torn down--after there are no 1580 * more in-flight requests to the parent image. When the last 1581 * reference is dropped, cleaning them up is safe. 1582 */ 1583 static void rbd_dev_parent_put(struct rbd_device *rbd_dev) 1584 { 1585 int counter; 1586 1587 if (!rbd_dev->parent_spec) 1588 return; 1589 1590 counter = atomic_dec_return_safe(&rbd_dev->parent_ref); 1591 if (counter > 0) 1592 return; 1593 1594 /* Last reference; clean up parent data structures */ 1595 1596 if (!counter) 1597 rbd_dev_unparent(rbd_dev); 1598 else 1599 rbd_warn(rbd_dev, "parent reference underflow"); 1600 } 1601 1602 /* 1603 * If an image has a non-zero parent overlap, get a reference to its 1604 * parent. 1605 * 1606 * Returns true if the rbd device has a parent with a non-zero 1607 * overlap and a reference for it was successfully taken, or 1608 * false otherwise. 1609 */ 1610 static bool rbd_dev_parent_get(struct rbd_device *rbd_dev) 1611 { 1612 int counter = 0; 1613 1614 if (!rbd_dev->parent_spec) 1615 return false; 1616 1617 down_read(&rbd_dev->header_rwsem); 1618 if (rbd_dev->parent_overlap) 1619 counter = atomic_inc_return_safe(&rbd_dev->parent_ref); 1620 up_read(&rbd_dev->header_rwsem); 1621 1622 if (counter < 0) 1623 rbd_warn(rbd_dev, "parent reference overflow"); 1624 1625 return counter > 0; 1626 } 1627 1628 /* 1629 * Caller is responsible for filling in the list of object requests 1630 * that comprises the image request, and the Linux request pointer 1631 * (if there is one). 1632 */ 1633 static struct rbd_img_request *rbd_img_request_create( 1634 struct rbd_device *rbd_dev, 1635 enum obj_operation_type op_type, 1636 struct ceph_snap_context *snapc) 1637 { 1638 struct rbd_img_request *img_request; 1639 1640 img_request = kmem_cache_zalloc(rbd_img_request_cache, GFP_NOIO); 1641 if (!img_request) 1642 return NULL; 1643 1644 img_request->rbd_dev = rbd_dev; 1645 img_request->op_type = op_type; 1646 if (!rbd_img_is_write(img_request)) 1647 img_request->snap_id = rbd_dev->spec->snap_id; 1648 else 1649 img_request->snapc = snapc; 1650 1651 if (rbd_dev_parent_get(rbd_dev)) 1652 img_request_layered_set(img_request); 1653 1654 spin_lock_init(&img_request->completion_lock); 1655 INIT_LIST_HEAD(&img_request->object_extents); 1656 kref_init(&img_request->kref); 1657 1658 dout("%s: rbd_dev %p %s -> img %p\n", __func__, rbd_dev, 1659 obj_op_name(op_type), img_request); 1660 return img_request; 1661 } 1662 1663 static void rbd_img_request_destroy(struct kref *kref) 1664 { 1665 struct rbd_img_request *img_request; 1666 struct rbd_obj_request *obj_request; 1667 struct rbd_obj_request *next_obj_request; 1668 1669 img_request = container_of(kref, struct rbd_img_request, kref); 1670 1671 dout("%s: img %p\n", __func__, img_request); 1672 1673 for_each_obj_request_safe(img_request, obj_request, next_obj_request) 1674 rbd_img_obj_request_del(img_request, obj_request); 1675 rbd_assert(img_request->obj_request_count == 0); 1676 1677 if (img_request_layered_test(img_request)) { 1678 img_request_layered_clear(img_request); 1679 rbd_dev_parent_put(img_request->rbd_dev); 1680 } 1681 1682 if (rbd_img_is_write(img_request)) 1683 ceph_put_snap_context(img_request->snapc); 1684 1685 kmem_cache_free(rbd_img_request_cache, img_request); 1686 } 1687 1688 static void prune_extents(struct ceph_file_extent *img_extents, 1689 u32 *num_img_extents, u64 overlap) 1690 { 1691 u32 cnt = *num_img_extents; 1692 1693 /* drop extents completely beyond the overlap */ 1694 while (cnt && img_extents[cnt - 1].fe_off >= overlap) 1695 cnt--; 1696 1697 if (cnt) { 1698 struct ceph_file_extent *ex = &img_extents[cnt - 1]; 1699 1700 /* trim final overlapping extent */ 1701 if (ex->fe_off + ex->fe_len > overlap) 1702 ex->fe_len = overlap - ex->fe_off; 1703 } 1704 1705 *num_img_extents = cnt; 1706 } 1707 1708 /* 1709 * Determine the byte range(s) covered by either just the object extent 1710 * or the entire object in the parent image. 1711 */ 1712 static int rbd_obj_calc_img_extents(struct rbd_obj_request *obj_req, 1713 bool entire) 1714 { 1715 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 1716 int ret; 1717 1718 if (!rbd_dev->parent_overlap) 1719 return 0; 1720 1721 ret = ceph_extent_to_file(&rbd_dev->layout, obj_req->ex.oe_objno, 1722 entire ? 0 : obj_req->ex.oe_off, 1723 entire ? rbd_dev->layout.object_size : 1724 obj_req->ex.oe_len, 1725 &obj_req->img_extents, 1726 &obj_req->num_img_extents); 1727 if (ret) 1728 return ret; 1729 1730 prune_extents(obj_req->img_extents, &obj_req->num_img_extents, 1731 rbd_dev->parent_overlap); 1732 return 0; 1733 } 1734 1735 static void rbd_osd_req_setup_data(struct rbd_obj_request *obj_req, u32 which) 1736 { 1737 switch (obj_req->img_request->data_type) { 1738 case OBJ_REQUEST_BIO: 1739 osd_req_op_extent_osd_data_bio(obj_req->osd_req, which, 1740 &obj_req->bio_pos, 1741 obj_req->ex.oe_len); 1742 break; 1743 case OBJ_REQUEST_BVECS: 1744 case OBJ_REQUEST_OWN_BVECS: 1745 rbd_assert(obj_req->bvec_pos.iter.bi_size == 1746 obj_req->ex.oe_len); 1747 rbd_assert(obj_req->bvec_idx == obj_req->bvec_count); 1748 osd_req_op_extent_osd_data_bvec_pos(obj_req->osd_req, which, 1749 &obj_req->bvec_pos); 1750 break; 1751 default: 1752 rbd_assert(0); 1753 } 1754 } 1755 1756 static int rbd_obj_setup_read(struct rbd_obj_request *obj_req) 1757 { 1758 obj_req->osd_req = rbd_osd_req_create(obj_req, 1); 1759 if (!obj_req->osd_req) 1760 return -ENOMEM; 1761 1762 osd_req_op_extent_init(obj_req->osd_req, 0, CEPH_OSD_OP_READ, 1763 obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0); 1764 rbd_osd_req_setup_data(obj_req, 0); 1765 1766 rbd_osd_req_format_read(obj_req); 1767 return 0; 1768 } 1769 1770 static int __rbd_obj_setup_stat(struct rbd_obj_request *obj_req, 1771 unsigned int which) 1772 { 1773 struct page **pages; 1774 1775 /* 1776 * The response data for a STAT call consists of: 1777 * le64 length; 1778 * struct { 1779 * le32 tv_sec; 1780 * le32 tv_nsec; 1781 * } mtime; 1782 */ 1783 pages = ceph_alloc_page_vector(1, GFP_NOIO); 1784 if (IS_ERR(pages)) 1785 return PTR_ERR(pages); 1786 1787 osd_req_op_init(obj_req->osd_req, which, CEPH_OSD_OP_STAT, 0); 1788 osd_req_op_raw_data_in_pages(obj_req->osd_req, which, pages, 1789 8 + sizeof(struct ceph_timespec), 1790 0, false, true); 1791 return 0; 1792 } 1793 1794 static void __rbd_obj_setup_write(struct rbd_obj_request *obj_req, 1795 unsigned int which) 1796 { 1797 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 1798 u16 opcode; 1799 1800 osd_req_op_alloc_hint_init(obj_req->osd_req, which++, 1801 rbd_dev->layout.object_size, 1802 rbd_dev->layout.object_size); 1803 1804 if (rbd_obj_is_entire(obj_req)) 1805 opcode = CEPH_OSD_OP_WRITEFULL; 1806 else 1807 opcode = CEPH_OSD_OP_WRITE; 1808 1809 osd_req_op_extent_init(obj_req->osd_req, which, opcode, 1810 obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0); 1811 rbd_osd_req_setup_data(obj_req, which++); 1812 1813 rbd_assert(which == obj_req->osd_req->r_num_ops); 1814 rbd_osd_req_format_write(obj_req); 1815 } 1816 1817 static int rbd_obj_setup_write(struct rbd_obj_request *obj_req) 1818 { 1819 unsigned int num_osd_ops, which = 0; 1820 int ret; 1821 1822 /* reverse map the entire object onto the parent */ 1823 ret = rbd_obj_calc_img_extents(obj_req, true); 1824 if (ret) 1825 return ret; 1826 1827 if (obj_req->num_img_extents) { 1828 obj_req->write_state = RBD_OBJ_WRITE_GUARD; 1829 num_osd_ops = 3; /* stat + setallochint + write/writefull */ 1830 } else { 1831 obj_req->write_state = RBD_OBJ_WRITE_FLAT; 1832 num_osd_ops = 2; /* setallochint + write/writefull */ 1833 } 1834 1835 obj_req->osd_req = rbd_osd_req_create(obj_req, num_osd_ops); 1836 if (!obj_req->osd_req) 1837 return -ENOMEM; 1838 1839 if (obj_req->num_img_extents) { 1840 ret = __rbd_obj_setup_stat(obj_req, which++); 1841 if (ret) 1842 return ret; 1843 } 1844 1845 __rbd_obj_setup_write(obj_req, which); 1846 return 0; 1847 } 1848 1849 static void __rbd_obj_setup_discard(struct rbd_obj_request *obj_req, 1850 unsigned int which) 1851 { 1852 u16 opcode; 1853 1854 if (rbd_obj_is_entire(obj_req)) { 1855 if (obj_req->num_img_extents) { 1856 osd_req_op_init(obj_req->osd_req, which++, 1857 CEPH_OSD_OP_CREATE, 0); 1858 opcode = CEPH_OSD_OP_TRUNCATE; 1859 } else { 1860 osd_req_op_init(obj_req->osd_req, which++, 1861 CEPH_OSD_OP_DELETE, 0); 1862 opcode = 0; 1863 } 1864 } else if (rbd_obj_is_tail(obj_req)) { 1865 opcode = CEPH_OSD_OP_TRUNCATE; 1866 } else { 1867 opcode = CEPH_OSD_OP_ZERO; 1868 } 1869 1870 if (opcode) 1871 osd_req_op_extent_init(obj_req->osd_req, which++, opcode, 1872 obj_req->ex.oe_off, obj_req->ex.oe_len, 1873 0, 0); 1874 1875 rbd_assert(which == obj_req->osd_req->r_num_ops); 1876 rbd_osd_req_format_write(obj_req); 1877 } 1878 1879 static int rbd_obj_setup_discard(struct rbd_obj_request *obj_req) 1880 { 1881 unsigned int num_osd_ops, which = 0; 1882 int ret; 1883 1884 /* reverse map the entire object onto the parent */ 1885 ret = rbd_obj_calc_img_extents(obj_req, true); 1886 if (ret) 1887 return ret; 1888 1889 if (rbd_obj_is_entire(obj_req)) { 1890 obj_req->write_state = RBD_OBJ_WRITE_FLAT; 1891 if (obj_req->num_img_extents) 1892 num_osd_ops = 2; /* create + truncate */ 1893 else 1894 num_osd_ops = 1; /* delete */ 1895 } else { 1896 if (obj_req->num_img_extents) { 1897 obj_req->write_state = RBD_OBJ_WRITE_GUARD; 1898 num_osd_ops = 2; /* stat + truncate/zero */ 1899 } else { 1900 obj_req->write_state = RBD_OBJ_WRITE_FLAT; 1901 num_osd_ops = 1; /* truncate/zero */ 1902 } 1903 } 1904 1905 obj_req->osd_req = rbd_osd_req_create(obj_req, num_osd_ops); 1906 if (!obj_req->osd_req) 1907 return -ENOMEM; 1908 1909 if (!rbd_obj_is_entire(obj_req) && obj_req->num_img_extents) { 1910 ret = __rbd_obj_setup_stat(obj_req, which++); 1911 if (ret) 1912 return ret; 1913 } 1914 1915 __rbd_obj_setup_discard(obj_req, which); 1916 return 0; 1917 } 1918 1919 /* 1920 * For each object request in @img_req, allocate an OSD request, add 1921 * individual OSD ops and prepare them for submission. The number of 1922 * OSD ops depends on op_type and the overlap point (if any). 1923 */ 1924 static int __rbd_img_fill_request(struct rbd_img_request *img_req) 1925 { 1926 struct rbd_obj_request *obj_req; 1927 int ret; 1928 1929 for_each_obj_request(img_req, obj_req) { 1930 switch (img_req->op_type) { 1931 case OBJ_OP_READ: 1932 ret = rbd_obj_setup_read(obj_req); 1933 break; 1934 case OBJ_OP_WRITE: 1935 ret = rbd_obj_setup_write(obj_req); 1936 break; 1937 case OBJ_OP_DISCARD: 1938 ret = rbd_obj_setup_discard(obj_req); 1939 break; 1940 default: 1941 rbd_assert(0); 1942 } 1943 if (ret) 1944 return ret; 1945 1946 ret = ceph_osdc_alloc_messages(obj_req->osd_req, GFP_NOIO); 1947 if (ret) 1948 return ret; 1949 } 1950 1951 return 0; 1952 } 1953 1954 union rbd_img_fill_iter { 1955 struct ceph_bio_iter bio_iter; 1956 struct ceph_bvec_iter bvec_iter; 1957 }; 1958 1959 struct rbd_img_fill_ctx { 1960 enum obj_request_type pos_type; 1961 union rbd_img_fill_iter *pos; 1962 union rbd_img_fill_iter iter; 1963 ceph_object_extent_fn_t set_pos_fn; 1964 ceph_object_extent_fn_t count_fn; 1965 ceph_object_extent_fn_t copy_fn; 1966 }; 1967 1968 static struct ceph_object_extent *alloc_object_extent(void *arg) 1969 { 1970 struct rbd_img_request *img_req = arg; 1971 struct rbd_obj_request *obj_req; 1972 1973 obj_req = rbd_obj_request_create(); 1974 if (!obj_req) 1975 return NULL; 1976 1977 rbd_img_obj_request_add(img_req, obj_req); 1978 return &obj_req->ex; 1979 } 1980 1981 /* 1982 * While su != os && sc == 1 is technically not fancy (it's the same 1983 * layout as su == os && sc == 1), we can't use the nocopy path for it 1984 * because ->set_pos_fn() should be called only once per object. 1985 * ceph_file_to_extents() invokes action_fn once per stripe unit, so 1986 * treat su != os && sc == 1 as fancy. 1987 */ 1988 static bool rbd_layout_is_fancy(struct ceph_file_layout *l) 1989 { 1990 return l->stripe_unit != l->object_size; 1991 } 1992 1993 static int rbd_img_fill_request_nocopy(struct rbd_img_request *img_req, 1994 struct ceph_file_extent *img_extents, 1995 u32 num_img_extents, 1996 struct rbd_img_fill_ctx *fctx) 1997 { 1998 u32 i; 1999 int ret; 2000 2001 img_req->data_type = fctx->pos_type; 2002 2003 /* 2004 * Create object requests and set each object request's starting 2005 * position in the provided bio (list) or bio_vec array. 2006 */ 2007 fctx->iter = *fctx->pos; 2008 for (i = 0; i < num_img_extents; i++) { 2009 ret = ceph_file_to_extents(&img_req->rbd_dev->layout, 2010 img_extents[i].fe_off, 2011 img_extents[i].fe_len, 2012 &img_req->object_extents, 2013 alloc_object_extent, img_req, 2014 fctx->set_pos_fn, &fctx->iter); 2015 if (ret) 2016 return ret; 2017 } 2018 2019 return __rbd_img_fill_request(img_req); 2020 } 2021 2022 /* 2023 * Map a list of image extents to a list of object extents, create the 2024 * corresponding object requests (normally each to a different object, 2025 * but not always) and add them to @img_req. For each object request, 2026 * set up its data descriptor to point to the corresponding chunk(s) of 2027 * @fctx->pos data buffer. 2028 * 2029 * Because ceph_file_to_extents() will merge adjacent object extents 2030 * together, each object request's data descriptor may point to multiple 2031 * different chunks of @fctx->pos data buffer. 2032 * 2033 * @fctx->pos data buffer is assumed to be large enough. 2034 */ 2035 static int rbd_img_fill_request(struct rbd_img_request *img_req, 2036 struct ceph_file_extent *img_extents, 2037 u32 num_img_extents, 2038 struct rbd_img_fill_ctx *fctx) 2039 { 2040 struct rbd_device *rbd_dev = img_req->rbd_dev; 2041 struct rbd_obj_request *obj_req; 2042 u32 i; 2043 int ret; 2044 2045 if (fctx->pos_type == OBJ_REQUEST_NODATA || 2046 !rbd_layout_is_fancy(&rbd_dev->layout)) 2047 return rbd_img_fill_request_nocopy(img_req, img_extents, 2048 num_img_extents, fctx); 2049 2050 img_req->data_type = OBJ_REQUEST_OWN_BVECS; 2051 2052 /* 2053 * Create object requests and determine ->bvec_count for each object 2054 * request. Note that ->bvec_count sum over all object requests may 2055 * be greater than the number of bio_vecs in the provided bio (list) 2056 * or bio_vec array because when mapped, those bio_vecs can straddle 2057 * stripe unit boundaries. 2058 */ 2059 fctx->iter = *fctx->pos; 2060 for (i = 0; i < num_img_extents; i++) { 2061 ret = ceph_file_to_extents(&rbd_dev->layout, 2062 img_extents[i].fe_off, 2063 img_extents[i].fe_len, 2064 &img_req->object_extents, 2065 alloc_object_extent, img_req, 2066 fctx->count_fn, &fctx->iter); 2067 if (ret) 2068 return ret; 2069 } 2070 2071 for_each_obj_request(img_req, obj_req) { 2072 obj_req->bvec_pos.bvecs = kmalloc_array(obj_req->bvec_count, 2073 sizeof(*obj_req->bvec_pos.bvecs), 2074 GFP_NOIO); 2075 if (!obj_req->bvec_pos.bvecs) 2076 return -ENOMEM; 2077 } 2078 2079 /* 2080 * Fill in each object request's private bio_vec array, splitting and 2081 * rearranging the provided bio_vecs in stripe unit chunks as needed. 2082 */ 2083 fctx->iter = *fctx->pos; 2084 for (i = 0; i < num_img_extents; i++) { 2085 ret = ceph_iterate_extents(&rbd_dev->layout, 2086 img_extents[i].fe_off, 2087 img_extents[i].fe_len, 2088 &img_req->object_extents, 2089 fctx->copy_fn, &fctx->iter); 2090 if (ret) 2091 return ret; 2092 } 2093 2094 return __rbd_img_fill_request(img_req); 2095 } 2096 2097 static int rbd_img_fill_nodata(struct rbd_img_request *img_req, 2098 u64 off, u64 len) 2099 { 2100 struct ceph_file_extent ex = { off, len }; 2101 union rbd_img_fill_iter dummy; 2102 struct rbd_img_fill_ctx fctx = { 2103 .pos_type = OBJ_REQUEST_NODATA, 2104 .pos = &dummy, 2105 }; 2106 2107 return rbd_img_fill_request(img_req, &ex, 1, &fctx); 2108 } 2109 2110 static void set_bio_pos(struct ceph_object_extent *ex, u32 bytes, void *arg) 2111 { 2112 struct rbd_obj_request *obj_req = 2113 container_of(ex, struct rbd_obj_request, ex); 2114 struct ceph_bio_iter *it = arg; 2115 2116 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes); 2117 obj_req->bio_pos = *it; 2118 ceph_bio_iter_advance(it, bytes); 2119 } 2120 2121 static void count_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg) 2122 { 2123 struct rbd_obj_request *obj_req = 2124 container_of(ex, struct rbd_obj_request, ex); 2125 struct ceph_bio_iter *it = arg; 2126 2127 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes); 2128 ceph_bio_iter_advance_step(it, bytes, ({ 2129 obj_req->bvec_count++; 2130 })); 2131 2132 } 2133 2134 static void copy_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg) 2135 { 2136 struct rbd_obj_request *obj_req = 2137 container_of(ex, struct rbd_obj_request, ex); 2138 struct ceph_bio_iter *it = arg; 2139 2140 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes); 2141 ceph_bio_iter_advance_step(it, bytes, ({ 2142 obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv; 2143 obj_req->bvec_pos.iter.bi_size += bv.bv_len; 2144 })); 2145 } 2146 2147 static int __rbd_img_fill_from_bio(struct rbd_img_request *img_req, 2148 struct ceph_file_extent *img_extents, 2149 u32 num_img_extents, 2150 struct ceph_bio_iter *bio_pos) 2151 { 2152 struct rbd_img_fill_ctx fctx = { 2153 .pos_type = OBJ_REQUEST_BIO, 2154 .pos = (union rbd_img_fill_iter *)bio_pos, 2155 .set_pos_fn = set_bio_pos, 2156 .count_fn = count_bio_bvecs, 2157 .copy_fn = copy_bio_bvecs, 2158 }; 2159 2160 return rbd_img_fill_request(img_req, img_extents, num_img_extents, 2161 &fctx); 2162 } 2163 2164 static int rbd_img_fill_from_bio(struct rbd_img_request *img_req, 2165 u64 off, u64 len, struct bio *bio) 2166 { 2167 struct ceph_file_extent ex = { off, len }; 2168 struct ceph_bio_iter it = { .bio = bio, .iter = bio->bi_iter }; 2169 2170 return __rbd_img_fill_from_bio(img_req, &ex, 1, &it); 2171 } 2172 2173 static void set_bvec_pos(struct ceph_object_extent *ex, u32 bytes, void *arg) 2174 { 2175 struct rbd_obj_request *obj_req = 2176 container_of(ex, struct rbd_obj_request, ex); 2177 struct ceph_bvec_iter *it = arg; 2178 2179 obj_req->bvec_pos = *it; 2180 ceph_bvec_iter_shorten(&obj_req->bvec_pos, bytes); 2181 ceph_bvec_iter_advance(it, bytes); 2182 } 2183 2184 static void count_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg) 2185 { 2186 struct rbd_obj_request *obj_req = 2187 container_of(ex, struct rbd_obj_request, ex); 2188 struct ceph_bvec_iter *it = arg; 2189 2190 ceph_bvec_iter_advance_step(it, bytes, ({ 2191 obj_req->bvec_count++; 2192 })); 2193 } 2194 2195 static void copy_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg) 2196 { 2197 struct rbd_obj_request *obj_req = 2198 container_of(ex, struct rbd_obj_request, ex); 2199 struct ceph_bvec_iter *it = arg; 2200 2201 ceph_bvec_iter_advance_step(it, bytes, ({ 2202 obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv; 2203 obj_req->bvec_pos.iter.bi_size += bv.bv_len; 2204 })); 2205 } 2206 2207 static int __rbd_img_fill_from_bvecs(struct rbd_img_request *img_req, 2208 struct ceph_file_extent *img_extents, 2209 u32 num_img_extents, 2210 struct ceph_bvec_iter *bvec_pos) 2211 { 2212 struct rbd_img_fill_ctx fctx = { 2213 .pos_type = OBJ_REQUEST_BVECS, 2214 .pos = (union rbd_img_fill_iter *)bvec_pos, 2215 .set_pos_fn = set_bvec_pos, 2216 .count_fn = count_bvecs, 2217 .copy_fn = copy_bvecs, 2218 }; 2219 2220 return rbd_img_fill_request(img_req, img_extents, num_img_extents, 2221 &fctx); 2222 } 2223 2224 static int rbd_img_fill_from_bvecs(struct rbd_img_request *img_req, 2225 struct ceph_file_extent *img_extents, 2226 u32 num_img_extents, 2227 struct bio_vec *bvecs) 2228 { 2229 struct ceph_bvec_iter it = { 2230 .bvecs = bvecs, 2231 .iter = { .bi_size = ceph_file_extents_bytes(img_extents, 2232 num_img_extents) }, 2233 }; 2234 2235 return __rbd_img_fill_from_bvecs(img_req, img_extents, num_img_extents, 2236 &it); 2237 } 2238 2239 static void rbd_img_request_submit(struct rbd_img_request *img_request) 2240 { 2241 struct rbd_obj_request *obj_request; 2242 2243 dout("%s: img %p\n", __func__, img_request); 2244 2245 rbd_img_request_get(img_request); 2246 for_each_obj_request(img_request, obj_request) 2247 rbd_obj_request_submit(obj_request); 2248 2249 rbd_img_request_put(img_request); 2250 } 2251 2252 static int rbd_obj_read_from_parent(struct rbd_obj_request *obj_req) 2253 { 2254 struct rbd_img_request *img_req = obj_req->img_request; 2255 struct rbd_img_request *child_img_req; 2256 int ret; 2257 2258 child_img_req = rbd_img_request_create(img_req->rbd_dev->parent, 2259 OBJ_OP_READ, NULL); 2260 if (!child_img_req) 2261 return -ENOMEM; 2262 2263 __set_bit(IMG_REQ_CHILD, &child_img_req->flags); 2264 child_img_req->obj_request = obj_req; 2265 2266 if (!rbd_img_is_write(img_req)) { 2267 switch (img_req->data_type) { 2268 case OBJ_REQUEST_BIO: 2269 ret = __rbd_img_fill_from_bio(child_img_req, 2270 obj_req->img_extents, 2271 obj_req->num_img_extents, 2272 &obj_req->bio_pos); 2273 break; 2274 case OBJ_REQUEST_BVECS: 2275 case OBJ_REQUEST_OWN_BVECS: 2276 ret = __rbd_img_fill_from_bvecs(child_img_req, 2277 obj_req->img_extents, 2278 obj_req->num_img_extents, 2279 &obj_req->bvec_pos); 2280 break; 2281 default: 2282 rbd_assert(0); 2283 } 2284 } else { 2285 ret = rbd_img_fill_from_bvecs(child_img_req, 2286 obj_req->img_extents, 2287 obj_req->num_img_extents, 2288 obj_req->copyup_bvecs); 2289 } 2290 if (ret) { 2291 rbd_img_request_put(child_img_req); 2292 return ret; 2293 } 2294 2295 rbd_img_request_submit(child_img_req); 2296 return 0; 2297 } 2298 2299 static bool rbd_obj_handle_read(struct rbd_obj_request *obj_req) 2300 { 2301 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2302 int ret; 2303 2304 if (obj_req->result == -ENOENT && 2305 rbd_dev->parent_overlap && !obj_req->tried_parent) { 2306 /* reverse map this object extent onto the parent */ 2307 ret = rbd_obj_calc_img_extents(obj_req, false); 2308 if (ret) { 2309 obj_req->result = ret; 2310 return true; 2311 } 2312 2313 if (obj_req->num_img_extents) { 2314 obj_req->tried_parent = true; 2315 ret = rbd_obj_read_from_parent(obj_req); 2316 if (ret) { 2317 obj_req->result = ret; 2318 return true; 2319 } 2320 return false; 2321 } 2322 } 2323 2324 /* 2325 * -ENOENT means a hole in the image -- zero-fill the entire 2326 * length of the request. A short read also implies zero-fill 2327 * to the end of the request. In both cases we update xferred 2328 * count to indicate the whole request was satisfied. 2329 */ 2330 if (obj_req->result == -ENOENT || 2331 (!obj_req->result && obj_req->xferred < obj_req->ex.oe_len)) { 2332 rbd_assert(!obj_req->xferred || !obj_req->result); 2333 rbd_obj_zero_range(obj_req, obj_req->xferred, 2334 obj_req->ex.oe_len - obj_req->xferred); 2335 obj_req->result = 0; 2336 obj_req->xferred = obj_req->ex.oe_len; 2337 } 2338 2339 return true; 2340 } 2341 2342 /* 2343 * copyup_bvecs pages are never highmem pages 2344 */ 2345 static bool is_zero_bvecs(struct bio_vec *bvecs, u32 bytes) 2346 { 2347 struct ceph_bvec_iter it = { 2348 .bvecs = bvecs, 2349 .iter = { .bi_size = bytes }, 2350 }; 2351 2352 ceph_bvec_iter_advance_step(&it, bytes, ({ 2353 if (memchr_inv(page_address(bv.bv_page) + bv.bv_offset, 0, 2354 bv.bv_len)) 2355 return false; 2356 })); 2357 return true; 2358 } 2359 2360 static int rbd_obj_issue_copyup(struct rbd_obj_request *obj_req, u32 bytes) 2361 { 2362 unsigned int num_osd_ops = obj_req->osd_req->r_num_ops; 2363 int ret; 2364 2365 dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes); 2366 rbd_assert(obj_req->osd_req->r_ops[0].op == CEPH_OSD_OP_STAT); 2367 rbd_osd_req_destroy(obj_req->osd_req); 2368 2369 /* 2370 * Create a copyup request with the same number of OSD ops as 2371 * the original request. The original request was stat + op(s), 2372 * the new copyup request will be copyup + the same op(s). 2373 */ 2374 obj_req->osd_req = rbd_osd_req_create(obj_req, num_osd_ops); 2375 if (!obj_req->osd_req) 2376 return -ENOMEM; 2377 2378 ret = osd_req_op_cls_init(obj_req->osd_req, 0, "rbd", "copyup"); 2379 if (ret) 2380 return ret; 2381 2382 /* 2383 * Only send non-zero copyup data to save some I/O and network 2384 * bandwidth -- zero copyup data is equivalent to the object not 2385 * existing. 2386 */ 2387 if (is_zero_bvecs(obj_req->copyup_bvecs, bytes)) { 2388 dout("%s obj_req %p detected zeroes\n", __func__, obj_req); 2389 bytes = 0; 2390 } 2391 osd_req_op_cls_request_data_bvecs(obj_req->osd_req, 0, 2392 obj_req->copyup_bvecs, 2393 obj_req->copyup_bvec_count, 2394 bytes); 2395 2396 switch (obj_req->img_request->op_type) { 2397 case OBJ_OP_WRITE: 2398 __rbd_obj_setup_write(obj_req, 1); 2399 break; 2400 case OBJ_OP_DISCARD: 2401 rbd_assert(!rbd_obj_is_entire(obj_req)); 2402 __rbd_obj_setup_discard(obj_req, 1); 2403 break; 2404 default: 2405 rbd_assert(0); 2406 } 2407 2408 ret = ceph_osdc_alloc_messages(obj_req->osd_req, GFP_NOIO); 2409 if (ret) 2410 return ret; 2411 2412 rbd_obj_request_submit(obj_req); 2413 return 0; 2414 } 2415 2416 static int setup_copyup_bvecs(struct rbd_obj_request *obj_req, u64 obj_overlap) 2417 { 2418 u32 i; 2419 2420 rbd_assert(!obj_req->copyup_bvecs); 2421 obj_req->copyup_bvec_count = calc_pages_for(0, obj_overlap); 2422 obj_req->copyup_bvecs = kcalloc(obj_req->copyup_bvec_count, 2423 sizeof(*obj_req->copyup_bvecs), 2424 GFP_NOIO); 2425 if (!obj_req->copyup_bvecs) 2426 return -ENOMEM; 2427 2428 for (i = 0; i < obj_req->copyup_bvec_count; i++) { 2429 unsigned int len = min(obj_overlap, (u64)PAGE_SIZE); 2430 2431 obj_req->copyup_bvecs[i].bv_page = alloc_page(GFP_NOIO); 2432 if (!obj_req->copyup_bvecs[i].bv_page) 2433 return -ENOMEM; 2434 2435 obj_req->copyup_bvecs[i].bv_offset = 0; 2436 obj_req->copyup_bvecs[i].bv_len = len; 2437 obj_overlap -= len; 2438 } 2439 2440 rbd_assert(!obj_overlap); 2441 return 0; 2442 } 2443 2444 static int rbd_obj_handle_write_guard(struct rbd_obj_request *obj_req) 2445 { 2446 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2447 int ret; 2448 2449 rbd_assert(obj_req->num_img_extents); 2450 prune_extents(obj_req->img_extents, &obj_req->num_img_extents, 2451 rbd_dev->parent_overlap); 2452 if (!obj_req->num_img_extents) { 2453 /* 2454 * The overlap has become 0 (most likely because the 2455 * image has been flattened). Use rbd_obj_issue_copyup() 2456 * to re-submit the original write request -- the copyup 2457 * operation itself will be a no-op, since someone must 2458 * have populated the child object while we weren't 2459 * looking. Move to WRITE_FLAT state as we'll be done 2460 * with the operation once the null copyup completes. 2461 */ 2462 obj_req->write_state = RBD_OBJ_WRITE_FLAT; 2463 return rbd_obj_issue_copyup(obj_req, 0); 2464 } 2465 2466 ret = setup_copyup_bvecs(obj_req, rbd_obj_img_extents_bytes(obj_req)); 2467 if (ret) 2468 return ret; 2469 2470 obj_req->write_state = RBD_OBJ_WRITE_COPYUP; 2471 return rbd_obj_read_from_parent(obj_req); 2472 } 2473 2474 static bool rbd_obj_handle_write(struct rbd_obj_request *obj_req) 2475 { 2476 int ret; 2477 2478 again: 2479 switch (obj_req->write_state) { 2480 case RBD_OBJ_WRITE_GUARD: 2481 rbd_assert(!obj_req->xferred); 2482 if (obj_req->result == -ENOENT) { 2483 /* 2484 * The target object doesn't exist. Read the data for 2485 * the entire target object up to the overlap point (if 2486 * any) from the parent, so we can use it for a copyup. 2487 */ 2488 ret = rbd_obj_handle_write_guard(obj_req); 2489 if (ret) { 2490 obj_req->result = ret; 2491 return true; 2492 } 2493 return false; 2494 } 2495 /* fall through */ 2496 case RBD_OBJ_WRITE_FLAT: 2497 if (!obj_req->result) 2498 /* 2499 * There is no such thing as a successful short 2500 * write -- indicate the whole request was satisfied. 2501 */ 2502 obj_req->xferred = obj_req->ex.oe_len; 2503 return true; 2504 case RBD_OBJ_WRITE_COPYUP: 2505 obj_req->write_state = RBD_OBJ_WRITE_GUARD; 2506 if (obj_req->result) 2507 goto again; 2508 2509 rbd_assert(obj_req->xferred); 2510 ret = rbd_obj_issue_copyup(obj_req, obj_req->xferred); 2511 if (ret) { 2512 obj_req->result = ret; 2513 return true; 2514 } 2515 return false; 2516 default: 2517 BUG(); 2518 } 2519 } 2520 2521 /* 2522 * Returns true if @obj_req is completed, or false otherwise. 2523 */ 2524 static bool __rbd_obj_handle_request(struct rbd_obj_request *obj_req) 2525 { 2526 switch (obj_req->img_request->op_type) { 2527 case OBJ_OP_READ: 2528 return rbd_obj_handle_read(obj_req); 2529 case OBJ_OP_WRITE: 2530 return rbd_obj_handle_write(obj_req); 2531 case OBJ_OP_DISCARD: 2532 if (rbd_obj_handle_write(obj_req)) { 2533 /* 2534 * Hide -ENOENT from delete/truncate/zero -- discarding 2535 * a non-existent object is not a problem. 2536 */ 2537 if (obj_req->result == -ENOENT) { 2538 obj_req->result = 0; 2539 obj_req->xferred = obj_req->ex.oe_len; 2540 } 2541 return true; 2542 } 2543 return false; 2544 default: 2545 BUG(); 2546 } 2547 } 2548 2549 static void rbd_obj_end_request(struct rbd_obj_request *obj_req) 2550 { 2551 struct rbd_img_request *img_req = obj_req->img_request; 2552 2553 rbd_assert((!obj_req->result && 2554 obj_req->xferred == obj_req->ex.oe_len) || 2555 (obj_req->result < 0 && !obj_req->xferred)); 2556 if (!obj_req->result) { 2557 img_req->xferred += obj_req->xferred; 2558 return; 2559 } 2560 2561 rbd_warn(img_req->rbd_dev, 2562 "%s at objno %llu %llu~%llu result %d xferred %llu", 2563 obj_op_name(img_req->op_type), obj_req->ex.oe_objno, 2564 obj_req->ex.oe_off, obj_req->ex.oe_len, obj_req->result, 2565 obj_req->xferred); 2566 if (!img_req->result) { 2567 img_req->result = obj_req->result; 2568 img_req->xferred = 0; 2569 } 2570 } 2571 2572 static void rbd_img_end_child_request(struct rbd_img_request *img_req) 2573 { 2574 struct rbd_obj_request *obj_req = img_req->obj_request; 2575 2576 rbd_assert(test_bit(IMG_REQ_CHILD, &img_req->flags)); 2577 rbd_assert((!img_req->result && 2578 img_req->xferred == rbd_obj_img_extents_bytes(obj_req)) || 2579 (img_req->result < 0 && !img_req->xferred)); 2580 2581 obj_req->result = img_req->result; 2582 obj_req->xferred = img_req->xferred; 2583 rbd_img_request_put(img_req); 2584 } 2585 2586 static void rbd_img_end_request(struct rbd_img_request *img_req) 2587 { 2588 rbd_assert(!test_bit(IMG_REQ_CHILD, &img_req->flags)); 2589 rbd_assert((!img_req->result && 2590 img_req->xferred == blk_rq_bytes(img_req->rq)) || 2591 (img_req->result < 0 && !img_req->xferred)); 2592 2593 blk_mq_end_request(img_req->rq, 2594 errno_to_blk_status(img_req->result)); 2595 rbd_img_request_put(img_req); 2596 } 2597 2598 static void rbd_obj_handle_request(struct rbd_obj_request *obj_req) 2599 { 2600 struct rbd_img_request *img_req; 2601 2602 again: 2603 if (!__rbd_obj_handle_request(obj_req)) 2604 return; 2605 2606 img_req = obj_req->img_request; 2607 spin_lock(&img_req->completion_lock); 2608 rbd_obj_end_request(obj_req); 2609 rbd_assert(img_req->pending_count); 2610 if (--img_req->pending_count) { 2611 spin_unlock(&img_req->completion_lock); 2612 return; 2613 } 2614 2615 spin_unlock(&img_req->completion_lock); 2616 if (test_bit(IMG_REQ_CHILD, &img_req->flags)) { 2617 obj_req = img_req->obj_request; 2618 rbd_img_end_child_request(img_req); 2619 goto again; 2620 } 2621 rbd_img_end_request(img_req); 2622 } 2623 2624 static const struct rbd_client_id rbd_empty_cid; 2625 2626 static bool rbd_cid_equal(const struct rbd_client_id *lhs, 2627 const struct rbd_client_id *rhs) 2628 { 2629 return lhs->gid == rhs->gid && lhs->handle == rhs->handle; 2630 } 2631 2632 static struct rbd_client_id rbd_get_cid(struct rbd_device *rbd_dev) 2633 { 2634 struct rbd_client_id cid; 2635 2636 mutex_lock(&rbd_dev->watch_mutex); 2637 cid.gid = ceph_client_gid(rbd_dev->rbd_client->client); 2638 cid.handle = rbd_dev->watch_cookie; 2639 mutex_unlock(&rbd_dev->watch_mutex); 2640 return cid; 2641 } 2642 2643 /* 2644 * lock_rwsem must be held for write 2645 */ 2646 static void rbd_set_owner_cid(struct rbd_device *rbd_dev, 2647 const struct rbd_client_id *cid) 2648 { 2649 dout("%s rbd_dev %p %llu-%llu -> %llu-%llu\n", __func__, rbd_dev, 2650 rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle, 2651 cid->gid, cid->handle); 2652 rbd_dev->owner_cid = *cid; /* struct */ 2653 } 2654 2655 static void format_lock_cookie(struct rbd_device *rbd_dev, char *buf) 2656 { 2657 mutex_lock(&rbd_dev->watch_mutex); 2658 sprintf(buf, "%s %llu", RBD_LOCK_COOKIE_PREFIX, rbd_dev->watch_cookie); 2659 mutex_unlock(&rbd_dev->watch_mutex); 2660 } 2661 2662 static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie) 2663 { 2664 struct rbd_client_id cid = rbd_get_cid(rbd_dev); 2665 2666 strcpy(rbd_dev->lock_cookie, cookie); 2667 rbd_set_owner_cid(rbd_dev, &cid); 2668 queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work); 2669 } 2670 2671 /* 2672 * lock_rwsem must be held for write 2673 */ 2674 static int rbd_lock(struct rbd_device *rbd_dev) 2675 { 2676 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 2677 char cookie[32]; 2678 int ret; 2679 2680 WARN_ON(__rbd_is_lock_owner(rbd_dev) || 2681 rbd_dev->lock_cookie[0] != '\0'); 2682 2683 format_lock_cookie(rbd_dev, cookie); 2684 ret = ceph_cls_lock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 2685 RBD_LOCK_NAME, CEPH_CLS_LOCK_EXCLUSIVE, cookie, 2686 RBD_LOCK_TAG, "", 0); 2687 if (ret) 2688 return ret; 2689 2690 rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED; 2691 __rbd_lock(rbd_dev, cookie); 2692 return 0; 2693 } 2694 2695 /* 2696 * lock_rwsem must be held for write 2697 */ 2698 static void rbd_unlock(struct rbd_device *rbd_dev) 2699 { 2700 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 2701 int ret; 2702 2703 WARN_ON(!__rbd_is_lock_owner(rbd_dev) || 2704 rbd_dev->lock_cookie[0] == '\0'); 2705 2706 ret = ceph_cls_unlock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 2707 RBD_LOCK_NAME, rbd_dev->lock_cookie); 2708 if (ret && ret != -ENOENT) 2709 rbd_warn(rbd_dev, "failed to unlock: %d", ret); 2710 2711 /* treat errors as the image is unlocked */ 2712 rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED; 2713 rbd_dev->lock_cookie[0] = '\0'; 2714 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid); 2715 queue_work(rbd_dev->task_wq, &rbd_dev->released_lock_work); 2716 } 2717 2718 static int __rbd_notify_op_lock(struct rbd_device *rbd_dev, 2719 enum rbd_notify_op notify_op, 2720 struct page ***preply_pages, 2721 size_t *preply_len) 2722 { 2723 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 2724 struct rbd_client_id cid = rbd_get_cid(rbd_dev); 2725 char buf[4 + 8 + 8 + CEPH_ENCODING_START_BLK_LEN]; 2726 int buf_size = sizeof(buf); 2727 void *p = buf; 2728 2729 dout("%s rbd_dev %p notify_op %d\n", __func__, rbd_dev, notify_op); 2730 2731 /* encode *LockPayload NotifyMessage (op + ClientId) */ 2732 ceph_start_encoding(&p, 2, 1, buf_size - CEPH_ENCODING_START_BLK_LEN); 2733 ceph_encode_32(&p, notify_op); 2734 ceph_encode_64(&p, cid.gid); 2735 ceph_encode_64(&p, cid.handle); 2736 2737 return ceph_osdc_notify(osdc, &rbd_dev->header_oid, 2738 &rbd_dev->header_oloc, buf, buf_size, 2739 RBD_NOTIFY_TIMEOUT, preply_pages, preply_len); 2740 } 2741 2742 static void rbd_notify_op_lock(struct rbd_device *rbd_dev, 2743 enum rbd_notify_op notify_op) 2744 { 2745 struct page **reply_pages; 2746 size_t reply_len; 2747 2748 __rbd_notify_op_lock(rbd_dev, notify_op, &reply_pages, &reply_len); 2749 ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len)); 2750 } 2751 2752 static void rbd_notify_acquired_lock(struct work_struct *work) 2753 { 2754 struct rbd_device *rbd_dev = container_of(work, struct rbd_device, 2755 acquired_lock_work); 2756 2757 rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_ACQUIRED_LOCK); 2758 } 2759 2760 static void rbd_notify_released_lock(struct work_struct *work) 2761 { 2762 struct rbd_device *rbd_dev = container_of(work, struct rbd_device, 2763 released_lock_work); 2764 2765 rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_RELEASED_LOCK); 2766 } 2767 2768 static int rbd_request_lock(struct rbd_device *rbd_dev) 2769 { 2770 struct page **reply_pages; 2771 size_t reply_len; 2772 bool lock_owner_responded = false; 2773 int ret; 2774 2775 dout("%s rbd_dev %p\n", __func__, rbd_dev); 2776 2777 ret = __rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_REQUEST_LOCK, 2778 &reply_pages, &reply_len); 2779 if (ret && ret != -ETIMEDOUT) { 2780 rbd_warn(rbd_dev, "failed to request lock: %d", ret); 2781 goto out; 2782 } 2783 2784 if (reply_len > 0 && reply_len <= PAGE_SIZE) { 2785 void *p = page_address(reply_pages[0]); 2786 void *const end = p + reply_len; 2787 u32 n; 2788 2789 ceph_decode_32_safe(&p, end, n, e_inval); /* num_acks */ 2790 while (n--) { 2791 u8 struct_v; 2792 u32 len; 2793 2794 ceph_decode_need(&p, end, 8 + 8, e_inval); 2795 p += 8 + 8; /* skip gid and cookie */ 2796 2797 ceph_decode_32_safe(&p, end, len, e_inval); 2798 if (!len) 2799 continue; 2800 2801 if (lock_owner_responded) { 2802 rbd_warn(rbd_dev, 2803 "duplicate lock owners detected"); 2804 ret = -EIO; 2805 goto out; 2806 } 2807 2808 lock_owner_responded = true; 2809 ret = ceph_start_decoding(&p, end, 1, "ResponseMessage", 2810 &struct_v, &len); 2811 if (ret) { 2812 rbd_warn(rbd_dev, 2813 "failed to decode ResponseMessage: %d", 2814 ret); 2815 goto e_inval; 2816 } 2817 2818 ret = ceph_decode_32(&p); 2819 } 2820 } 2821 2822 if (!lock_owner_responded) { 2823 rbd_warn(rbd_dev, "no lock owners detected"); 2824 ret = -ETIMEDOUT; 2825 } 2826 2827 out: 2828 ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len)); 2829 return ret; 2830 2831 e_inval: 2832 ret = -EINVAL; 2833 goto out; 2834 } 2835 2836 static void wake_requests(struct rbd_device *rbd_dev, bool wake_all) 2837 { 2838 dout("%s rbd_dev %p wake_all %d\n", __func__, rbd_dev, wake_all); 2839 2840 cancel_delayed_work(&rbd_dev->lock_dwork); 2841 if (wake_all) 2842 wake_up_all(&rbd_dev->lock_waitq); 2843 else 2844 wake_up(&rbd_dev->lock_waitq); 2845 } 2846 2847 static int get_lock_owner_info(struct rbd_device *rbd_dev, 2848 struct ceph_locker **lockers, u32 *num_lockers) 2849 { 2850 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 2851 u8 lock_type; 2852 char *lock_tag; 2853 int ret; 2854 2855 dout("%s rbd_dev %p\n", __func__, rbd_dev); 2856 2857 ret = ceph_cls_lock_info(osdc, &rbd_dev->header_oid, 2858 &rbd_dev->header_oloc, RBD_LOCK_NAME, 2859 &lock_type, &lock_tag, lockers, num_lockers); 2860 if (ret) 2861 return ret; 2862 2863 if (*num_lockers == 0) { 2864 dout("%s rbd_dev %p no lockers detected\n", __func__, rbd_dev); 2865 goto out; 2866 } 2867 2868 if (strcmp(lock_tag, RBD_LOCK_TAG)) { 2869 rbd_warn(rbd_dev, "locked by external mechanism, tag %s", 2870 lock_tag); 2871 ret = -EBUSY; 2872 goto out; 2873 } 2874 2875 if (lock_type == CEPH_CLS_LOCK_SHARED) { 2876 rbd_warn(rbd_dev, "shared lock type detected"); 2877 ret = -EBUSY; 2878 goto out; 2879 } 2880 2881 if (strncmp((*lockers)[0].id.cookie, RBD_LOCK_COOKIE_PREFIX, 2882 strlen(RBD_LOCK_COOKIE_PREFIX))) { 2883 rbd_warn(rbd_dev, "locked by external mechanism, cookie %s", 2884 (*lockers)[0].id.cookie); 2885 ret = -EBUSY; 2886 goto out; 2887 } 2888 2889 out: 2890 kfree(lock_tag); 2891 return ret; 2892 } 2893 2894 static int find_watcher(struct rbd_device *rbd_dev, 2895 const struct ceph_locker *locker) 2896 { 2897 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 2898 struct ceph_watch_item *watchers; 2899 u32 num_watchers; 2900 u64 cookie; 2901 int i; 2902 int ret; 2903 2904 ret = ceph_osdc_list_watchers(osdc, &rbd_dev->header_oid, 2905 &rbd_dev->header_oloc, &watchers, 2906 &num_watchers); 2907 if (ret) 2908 return ret; 2909 2910 sscanf(locker->id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu", &cookie); 2911 for (i = 0; i < num_watchers; i++) { 2912 if (!memcmp(&watchers[i].addr, &locker->info.addr, 2913 sizeof(locker->info.addr)) && 2914 watchers[i].cookie == cookie) { 2915 struct rbd_client_id cid = { 2916 .gid = le64_to_cpu(watchers[i].name.num), 2917 .handle = cookie, 2918 }; 2919 2920 dout("%s rbd_dev %p found cid %llu-%llu\n", __func__, 2921 rbd_dev, cid.gid, cid.handle); 2922 rbd_set_owner_cid(rbd_dev, &cid); 2923 ret = 1; 2924 goto out; 2925 } 2926 } 2927 2928 dout("%s rbd_dev %p no watchers\n", __func__, rbd_dev); 2929 ret = 0; 2930 out: 2931 kfree(watchers); 2932 return ret; 2933 } 2934 2935 /* 2936 * lock_rwsem must be held for write 2937 */ 2938 static int rbd_try_lock(struct rbd_device *rbd_dev) 2939 { 2940 struct ceph_client *client = rbd_dev->rbd_client->client; 2941 struct ceph_locker *lockers; 2942 u32 num_lockers; 2943 int ret; 2944 2945 for (;;) { 2946 ret = rbd_lock(rbd_dev); 2947 if (ret != -EBUSY) 2948 return ret; 2949 2950 /* determine if the current lock holder is still alive */ 2951 ret = get_lock_owner_info(rbd_dev, &lockers, &num_lockers); 2952 if (ret) 2953 return ret; 2954 2955 if (num_lockers == 0) 2956 goto again; 2957 2958 ret = find_watcher(rbd_dev, lockers); 2959 if (ret) { 2960 if (ret > 0) 2961 ret = 0; /* have to request lock */ 2962 goto out; 2963 } 2964 2965 rbd_warn(rbd_dev, "%s%llu seems dead, breaking lock", 2966 ENTITY_NAME(lockers[0].id.name)); 2967 2968 ret = ceph_monc_blacklist_add(&client->monc, 2969 &lockers[0].info.addr); 2970 if (ret) { 2971 rbd_warn(rbd_dev, "blacklist of %s%llu failed: %d", 2972 ENTITY_NAME(lockers[0].id.name), ret); 2973 goto out; 2974 } 2975 2976 ret = ceph_cls_break_lock(&client->osdc, &rbd_dev->header_oid, 2977 &rbd_dev->header_oloc, RBD_LOCK_NAME, 2978 lockers[0].id.cookie, 2979 &lockers[0].id.name); 2980 if (ret && ret != -ENOENT) 2981 goto out; 2982 2983 again: 2984 ceph_free_lockers(lockers, num_lockers); 2985 } 2986 2987 out: 2988 ceph_free_lockers(lockers, num_lockers); 2989 return ret; 2990 } 2991 2992 /* 2993 * ret is set only if lock_state is RBD_LOCK_STATE_UNLOCKED 2994 */ 2995 static enum rbd_lock_state rbd_try_acquire_lock(struct rbd_device *rbd_dev, 2996 int *pret) 2997 { 2998 enum rbd_lock_state lock_state; 2999 3000 down_read(&rbd_dev->lock_rwsem); 3001 dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev, 3002 rbd_dev->lock_state); 3003 if (__rbd_is_lock_owner(rbd_dev)) { 3004 lock_state = rbd_dev->lock_state; 3005 up_read(&rbd_dev->lock_rwsem); 3006 return lock_state; 3007 } 3008 3009 up_read(&rbd_dev->lock_rwsem); 3010 down_write(&rbd_dev->lock_rwsem); 3011 dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev, 3012 rbd_dev->lock_state); 3013 if (!__rbd_is_lock_owner(rbd_dev)) { 3014 *pret = rbd_try_lock(rbd_dev); 3015 if (*pret) 3016 rbd_warn(rbd_dev, "failed to acquire lock: %d", *pret); 3017 } 3018 3019 lock_state = rbd_dev->lock_state; 3020 up_write(&rbd_dev->lock_rwsem); 3021 return lock_state; 3022 } 3023 3024 static void rbd_acquire_lock(struct work_struct *work) 3025 { 3026 struct rbd_device *rbd_dev = container_of(to_delayed_work(work), 3027 struct rbd_device, lock_dwork); 3028 enum rbd_lock_state lock_state; 3029 int ret = 0; 3030 3031 dout("%s rbd_dev %p\n", __func__, rbd_dev); 3032 again: 3033 lock_state = rbd_try_acquire_lock(rbd_dev, &ret); 3034 if (lock_state != RBD_LOCK_STATE_UNLOCKED || ret == -EBLACKLISTED) { 3035 if (lock_state == RBD_LOCK_STATE_LOCKED) 3036 wake_requests(rbd_dev, true); 3037 dout("%s rbd_dev %p lock_state %d ret %d - done\n", __func__, 3038 rbd_dev, lock_state, ret); 3039 return; 3040 } 3041 3042 ret = rbd_request_lock(rbd_dev); 3043 if (ret == -ETIMEDOUT) { 3044 goto again; /* treat this as a dead client */ 3045 } else if (ret == -EROFS) { 3046 rbd_warn(rbd_dev, "peer will not release lock"); 3047 /* 3048 * If this is rbd_add_acquire_lock(), we want to fail 3049 * immediately -- reuse BLACKLISTED flag. Otherwise we 3050 * want to block. 3051 */ 3052 if (!(rbd_dev->disk->flags & GENHD_FL_UP)) { 3053 set_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags); 3054 /* wake "rbd map --exclusive" process */ 3055 wake_requests(rbd_dev, false); 3056 } 3057 } else if (ret < 0) { 3058 rbd_warn(rbd_dev, "error requesting lock: %d", ret); 3059 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 3060 RBD_RETRY_DELAY); 3061 } else { 3062 /* 3063 * lock owner acked, but resend if we don't see them 3064 * release the lock 3065 */ 3066 dout("%s rbd_dev %p requeueing lock_dwork\n", __func__, 3067 rbd_dev); 3068 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 3069 msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC)); 3070 } 3071 } 3072 3073 /* 3074 * lock_rwsem must be held for write 3075 */ 3076 static bool rbd_release_lock(struct rbd_device *rbd_dev) 3077 { 3078 dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev, 3079 rbd_dev->lock_state); 3080 if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED) 3081 return false; 3082 3083 rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING; 3084 downgrade_write(&rbd_dev->lock_rwsem); 3085 /* 3086 * Ensure that all in-flight IO is flushed. 3087 * 3088 * FIXME: ceph_osdc_sync() flushes the entire OSD client, which 3089 * may be shared with other devices. 3090 */ 3091 ceph_osdc_sync(&rbd_dev->rbd_client->client->osdc); 3092 up_read(&rbd_dev->lock_rwsem); 3093 3094 down_write(&rbd_dev->lock_rwsem); 3095 dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev, 3096 rbd_dev->lock_state); 3097 if (rbd_dev->lock_state != RBD_LOCK_STATE_RELEASING) 3098 return false; 3099 3100 rbd_unlock(rbd_dev); 3101 /* 3102 * Give others a chance to grab the lock - we would re-acquire 3103 * almost immediately if we got new IO during ceph_osdc_sync() 3104 * otherwise. We need to ack our own notifications, so this 3105 * lock_dwork will be requeued from rbd_wait_state_locked() 3106 * after wake_requests() in rbd_handle_released_lock(). 3107 */ 3108 cancel_delayed_work(&rbd_dev->lock_dwork); 3109 return true; 3110 } 3111 3112 static void rbd_release_lock_work(struct work_struct *work) 3113 { 3114 struct rbd_device *rbd_dev = container_of(work, struct rbd_device, 3115 unlock_work); 3116 3117 down_write(&rbd_dev->lock_rwsem); 3118 rbd_release_lock(rbd_dev); 3119 up_write(&rbd_dev->lock_rwsem); 3120 } 3121 3122 static void rbd_handle_acquired_lock(struct rbd_device *rbd_dev, u8 struct_v, 3123 void **p) 3124 { 3125 struct rbd_client_id cid = { 0 }; 3126 3127 if (struct_v >= 2) { 3128 cid.gid = ceph_decode_64(p); 3129 cid.handle = ceph_decode_64(p); 3130 } 3131 3132 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid, 3133 cid.handle); 3134 if (!rbd_cid_equal(&cid, &rbd_empty_cid)) { 3135 down_write(&rbd_dev->lock_rwsem); 3136 if (rbd_cid_equal(&cid, &rbd_dev->owner_cid)) { 3137 /* 3138 * we already know that the remote client is 3139 * the owner 3140 */ 3141 up_write(&rbd_dev->lock_rwsem); 3142 return; 3143 } 3144 3145 rbd_set_owner_cid(rbd_dev, &cid); 3146 downgrade_write(&rbd_dev->lock_rwsem); 3147 } else { 3148 down_read(&rbd_dev->lock_rwsem); 3149 } 3150 3151 if (!__rbd_is_lock_owner(rbd_dev)) 3152 wake_requests(rbd_dev, false); 3153 up_read(&rbd_dev->lock_rwsem); 3154 } 3155 3156 static void rbd_handle_released_lock(struct rbd_device *rbd_dev, u8 struct_v, 3157 void **p) 3158 { 3159 struct rbd_client_id cid = { 0 }; 3160 3161 if (struct_v >= 2) { 3162 cid.gid = ceph_decode_64(p); 3163 cid.handle = ceph_decode_64(p); 3164 } 3165 3166 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid, 3167 cid.handle); 3168 if (!rbd_cid_equal(&cid, &rbd_empty_cid)) { 3169 down_write(&rbd_dev->lock_rwsem); 3170 if (!rbd_cid_equal(&cid, &rbd_dev->owner_cid)) { 3171 dout("%s rbd_dev %p unexpected owner, cid %llu-%llu != owner_cid %llu-%llu\n", 3172 __func__, rbd_dev, cid.gid, cid.handle, 3173 rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle); 3174 up_write(&rbd_dev->lock_rwsem); 3175 return; 3176 } 3177 3178 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid); 3179 downgrade_write(&rbd_dev->lock_rwsem); 3180 } else { 3181 down_read(&rbd_dev->lock_rwsem); 3182 } 3183 3184 if (!__rbd_is_lock_owner(rbd_dev)) 3185 wake_requests(rbd_dev, false); 3186 up_read(&rbd_dev->lock_rwsem); 3187 } 3188 3189 /* 3190 * Returns result for ResponseMessage to be encoded (<= 0), or 1 if no 3191 * ResponseMessage is needed. 3192 */ 3193 static int rbd_handle_request_lock(struct rbd_device *rbd_dev, u8 struct_v, 3194 void **p) 3195 { 3196 struct rbd_client_id my_cid = rbd_get_cid(rbd_dev); 3197 struct rbd_client_id cid = { 0 }; 3198 int result = 1; 3199 3200 if (struct_v >= 2) { 3201 cid.gid = ceph_decode_64(p); 3202 cid.handle = ceph_decode_64(p); 3203 } 3204 3205 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid, 3206 cid.handle); 3207 if (rbd_cid_equal(&cid, &my_cid)) 3208 return result; 3209 3210 down_read(&rbd_dev->lock_rwsem); 3211 if (__rbd_is_lock_owner(rbd_dev)) { 3212 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED && 3213 rbd_cid_equal(&rbd_dev->owner_cid, &rbd_empty_cid)) 3214 goto out_unlock; 3215 3216 /* 3217 * encode ResponseMessage(0) so the peer can detect 3218 * a missing owner 3219 */ 3220 result = 0; 3221 3222 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) { 3223 if (!rbd_dev->opts->exclusive) { 3224 dout("%s rbd_dev %p queueing unlock_work\n", 3225 __func__, rbd_dev); 3226 queue_work(rbd_dev->task_wq, 3227 &rbd_dev->unlock_work); 3228 } else { 3229 /* refuse to release the lock */ 3230 result = -EROFS; 3231 } 3232 } 3233 } 3234 3235 out_unlock: 3236 up_read(&rbd_dev->lock_rwsem); 3237 return result; 3238 } 3239 3240 static void __rbd_acknowledge_notify(struct rbd_device *rbd_dev, 3241 u64 notify_id, u64 cookie, s32 *result) 3242 { 3243 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3244 char buf[4 + CEPH_ENCODING_START_BLK_LEN]; 3245 int buf_size = sizeof(buf); 3246 int ret; 3247 3248 if (result) { 3249 void *p = buf; 3250 3251 /* encode ResponseMessage */ 3252 ceph_start_encoding(&p, 1, 1, 3253 buf_size - CEPH_ENCODING_START_BLK_LEN); 3254 ceph_encode_32(&p, *result); 3255 } else { 3256 buf_size = 0; 3257 } 3258 3259 ret = ceph_osdc_notify_ack(osdc, &rbd_dev->header_oid, 3260 &rbd_dev->header_oloc, notify_id, cookie, 3261 buf, buf_size); 3262 if (ret) 3263 rbd_warn(rbd_dev, "acknowledge_notify failed: %d", ret); 3264 } 3265 3266 static void rbd_acknowledge_notify(struct rbd_device *rbd_dev, u64 notify_id, 3267 u64 cookie) 3268 { 3269 dout("%s rbd_dev %p\n", __func__, rbd_dev); 3270 __rbd_acknowledge_notify(rbd_dev, notify_id, cookie, NULL); 3271 } 3272 3273 static void rbd_acknowledge_notify_result(struct rbd_device *rbd_dev, 3274 u64 notify_id, u64 cookie, s32 result) 3275 { 3276 dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result); 3277 __rbd_acknowledge_notify(rbd_dev, notify_id, cookie, &result); 3278 } 3279 3280 static void rbd_watch_cb(void *arg, u64 notify_id, u64 cookie, 3281 u64 notifier_id, void *data, size_t data_len) 3282 { 3283 struct rbd_device *rbd_dev = arg; 3284 void *p = data; 3285 void *const end = p + data_len; 3286 u8 struct_v = 0; 3287 u32 len; 3288 u32 notify_op; 3289 int ret; 3290 3291 dout("%s rbd_dev %p cookie %llu notify_id %llu data_len %zu\n", 3292 __func__, rbd_dev, cookie, notify_id, data_len); 3293 if (data_len) { 3294 ret = ceph_start_decoding(&p, end, 1, "NotifyMessage", 3295 &struct_v, &len); 3296 if (ret) { 3297 rbd_warn(rbd_dev, "failed to decode NotifyMessage: %d", 3298 ret); 3299 return; 3300 } 3301 3302 notify_op = ceph_decode_32(&p); 3303 } else { 3304 /* legacy notification for header updates */ 3305 notify_op = RBD_NOTIFY_OP_HEADER_UPDATE; 3306 len = 0; 3307 } 3308 3309 dout("%s rbd_dev %p notify_op %u\n", __func__, rbd_dev, notify_op); 3310 switch (notify_op) { 3311 case RBD_NOTIFY_OP_ACQUIRED_LOCK: 3312 rbd_handle_acquired_lock(rbd_dev, struct_v, &p); 3313 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 3314 break; 3315 case RBD_NOTIFY_OP_RELEASED_LOCK: 3316 rbd_handle_released_lock(rbd_dev, struct_v, &p); 3317 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 3318 break; 3319 case RBD_NOTIFY_OP_REQUEST_LOCK: 3320 ret = rbd_handle_request_lock(rbd_dev, struct_v, &p); 3321 if (ret <= 0) 3322 rbd_acknowledge_notify_result(rbd_dev, notify_id, 3323 cookie, ret); 3324 else 3325 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 3326 break; 3327 case RBD_NOTIFY_OP_HEADER_UPDATE: 3328 ret = rbd_dev_refresh(rbd_dev); 3329 if (ret) 3330 rbd_warn(rbd_dev, "refresh failed: %d", ret); 3331 3332 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 3333 break; 3334 default: 3335 if (rbd_is_lock_owner(rbd_dev)) 3336 rbd_acknowledge_notify_result(rbd_dev, notify_id, 3337 cookie, -EOPNOTSUPP); 3338 else 3339 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 3340 break; 3341 } 3342 } 3343 3344 static void __rbd_unregister_watch(struct rbd_device *rbd_dev); 3345 3346 static void rbd_watch_errcb(void *arg, u64 cookie, int err) 3347 { 3348 struct rbd_device *rbd_dev = arg; 3349 3350 rbd_warn(rbd_dev, "encountered watch error: %d", err); 3351 3352 down_write(&rbd_dev->lock_rwsem); 3353 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid); 3354 up_write(&rbd_dev->lock_rwsem); 3355 3356 mutex_lock(&rbd_dev->watch_mutex); 3357 if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) { 3358 __rbd_unregister_watch(rbd_dev); 3359 rbd_dev->watch_state = RBD_WATCH_STATE_ERROR; 3360 3361 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->watch_dwork, 0); 3362 } 3363 mutex_unlock(&rbd_dev->watch_mutex); 3364 } 3365 3366 /* 3367 * watch_mutex must be locked 3368 */ 3369 static int __rbd_register_watch(struct rbd_device *rbd_dev) 3370 { 3371 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3372 struct ceph_osd_linger_request *handle; 3373 3374 rbd_assert(!rbd_dev->watch_handle); 3375 dout("%s rbd_dev %p\n", __func__, rbd_dev); 3376 3377 handle = ceph_osdc_watch(osdc, &rbd_dev->header_oid, 3378 &rbd_dev->header_oloc, rbd_watch_cb, 3379 rbd_watch_errcb, rbd_dev); 3380 if (IS_ERR(handle)) 3381 return PTR_ERR(handle); 3382 3383 rbd_dev->watch_handle = handle; 3384 return 0; 3385 } 3386 3387 /* 3388 * watch_mutex must be locked 3389 */ 3390 static void __rbd_unregister_watch(struct rbd_device *rbd_dev) 3391 { 3392 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3393 int ret; 3394 3395 rbd_assert(rbd_dev->watch_handle); 3396 dout("%s rbd_dev %p\n", __func__, rbd_dev); 3397 3398 ret = ceph_osdc_unwatch(osdc, rbd_dev->watch_handle); 3399 if (ret) 3400 rbd_warn(rbd_dev, "failed to unwatch: %d", ret); 3401 3402 rbd_dev->watch_handle = NULL; 3403 } 3404 3405 static int rbd_register_watch(struct rbd_device *rbd_dev) 3406 { 3407 int ret; 3408 3409 mutex_lock(&rbd_dev->watch_mutex); 3410 rbd_assert(rbd_dev->watch_state == RBD_WATCH_STATE_UNREGISTERED); 3411 ret = __rbd_register_watch(rbd_dev); 3412 if (ret) 3413 goto out; 3414 3415 rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED; 3416 rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id; 3417 3418 out: 3419 mutex_unlock(&rbd_dev->watch_mutex); 3420 return ret; 3421 } 3422 3423 static void cancel_tasks_sync(struct rbd_device *rbd_dev) 3424 { 3425 dout("%s rbd_dev %p\n", __func__, rbd_dev); 3426 3427 cancel_work_sync(&rbd_dev->acquired_lock_work); 3428 cancel_work_sync(&rbd_dev->released_lock_work); 3429 cancel_delayed_work_sync(&rbd_dev->lock_dwork); 3430 cancel_work_sync(&rbd_dev->unlock_work); 3431 } 3432 3433 static void rbd_unregister_watch(struct rbd_device *rbd_dev) 3434 { 3435 WARN_ON(waitqueue_active(&rbd_dev->lock_waitq)); 3436 cancel_tasks_sync(rbd_dev); 3437 3438 mutex_lock(&rbd_dev->watch_mutex); 3439 if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) 3440 __rbd_unregister_watch(rbd_dev); 3441 rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED; 3442 mutex_unlock(&rbd_dev->watch_mutex); 3443 3444 cancel_delayed_work_sync(&rbd_dev->watch_dwork); 3445 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc); 3446 } 3447 3448 /* 3449 * lock_rwsem must be held for write 3450 */ 3451 static void rbd_reacquire_lock(struct rbd_device *rbd_dev) 3452 { 3453 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3454 char cookie[32]; 3455 int ret; 3456 3457 WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED); 3458 3459 format_lock_cookie(rbd_dev, cookie); 3460 ret = ceph_cls_set_cookie(osdc, &rbd_dev->header_oid, 3461 &rbd_dev->header_oloc, RBD_LOCK_NAME, 3462 CEPH_CLS_LOCK_EXCLUSIVE, rbd_dev->lock_cookie, 3463 RBD_LOCK_TAG, cookie); 3464 if (ret) { 3465 if (ret != -EOPNOTSUPP) 3466 rbd_warn(rbd_dev, "failed to update lock cookie: %d", 3467 ret); 3468 3469 /* 3470 * Lock cookie cannot be updated on older OSDs, so do 3471 * a manual release and queue an acquire. 3472 */ 3473 if (rbd_release_lock(rbd_dev)) 3474 queue_delayed_work(rbd_dev->task_wq, 3475 &rbd_dev->lock_dwork, 0); 3476 } else { 3477 __rbd_lock(rbd_dev, cookie); 3478 } 3479 } 3480 3481 static void rbd_reregister_watch(struct work_struct *work) 3482 { 3483 struct rbd_device *rbd_dev = container_of(to_delayed_work(work), 3484 struct rbd_device, watch_dwork); 3485 int ret; 3486 3487 dout("%s rbd_dev %p\n", __func__, rbd_dev); 3488 3489 mutex_lock(&rbd_dev->watch_mutex); 3490 if (rbd_dev->watch_state != RBD_WATCH_STATE_ERROR) { 3491 mutex_unlock(&rbd_dev->watch_mutex); 3492 return; 3493 } 3494 3495 ret = __rbd_register_watch(rbd_dev); 3496 if (ret) { 3497 rbd_warn(rbd_dev, "failed to reregister watch: %d", ret); 3498 if (ret == -EBLACKLISTED || ret == -ENOENT) { 3499 set_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags); 3500 wake_requests(rbd_dev, true); 3501 } else { 3502 queue_delayed_work(rbd_dev->task_wq, 3503 &rbd_dev->watch_dwork, 3504 RBD_RETRY_DELAY); 3505 } 3506 mutex_unlock(&rbd_dev->watch_mutex); 3507 return; 3508 } 3509 3510 rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED; 3511 rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id; 3512 mutex_unlock(&rbd_dev->watch_mutex); 3513 3514 down_write(&rbd_dev->lock_rwsem); 3515 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) 3516 rbd_reacquire_lock(rbd_dev); 3517 up_write(&rbd_dev->lock_rwsem); 3518 3519 ret = rbd_dev_refresh(rbd_dev); 3520 if (ret) 3521 rbd_warn(rbd_dev, "reregistration refresh failed: %d", ret); 3522 } 3523 3524 /* 3525 * Synchronous osd object method call. Returns the number of bytes 3526 * returned in the outbound buffer, or a negative error code. 3527 */ 3528 static int rbd_obj_method_sync(struct rbd_device *rbd_dev, 3529 struct ceph_object_id *oid, 3530 struct ceph_object_locator *oloc, 3531 const char *method_name, 3532 const void *outbound, 3533 size_t outbound_size, 3534 void *inbound, 3535 size_t inbound_size) 3536 { 3537 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3538 struct page *req_page = NULL; 3539 struct page *reply_page; 3540 int ret; 3541 3542 /* 3543 * Method calls are ultimately read operations. The result 3544 * should placed into the inbound buffer provided. They 3545 * also supply outbound data--parameters for the object 3546 * method. Currently if this is present it will be a 3547 * snapshot id. 3548 */ 3549 if (outbound) { 3550 if (outbound_size > PAGE_SIZE) 3551 return -E2BIG; 3552 3553 req_page = alloc_page(GFP_KERNEL); 3554 if (!req_page) 3555 return -ENOMEM; 3556 3557 memcpy(page_address(req_page), outbound, outbound_size); 3558 } 3559 3560 reply_page = alloc_page(GFP_KERNEL); 3561 if (!reply_page) { 3562 if (req_page) 3563 __free_page(req_page); 3564 return -ENOMEM; 3565 } 3566 3567 ret = ceph_osdc_call(osdc, oid, oloc, RBD_DRV_NAME, method_name, 3568 CEPH_OSD_FLAG_READ, req_page, outbound_size, 3569 reply_page, &inbound_size); 3570 if (!ret) { 3571 memcpy(inbound, page_address(reply_page), inbound_size); 3572 ret = inbound_size; 3573 } 3574 3575 if (req_page) 3576 __free_page(req_page); 3577 __free_page(reply_page); 3578 return ret; 3579 } 3580 3581 /* 3582 * lock_rwsem must be held for read 3583 */ 3584 static int rbd_wait_state_locked(struct rbd_device *rbd_dev, bool may_acquire) 3585 { 3586 DEFINE_WAIT(wait); 3587 unsigned long timeout; 3588 int ret = 0; 3589 3590 if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) 3591 return -EBLACKLISTED; 3592 3593 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) 3594 return 0; 3595 3596 if (!may_acquire) { 3597 rbd_warn(rbd_dev, "exclusive lock required"); 3598 return -EROFS; 3599 } 3600 3601 do { 3602 /* 3603 * Note the use of mod_delayed_work() in rbd_acquire_lock() 3604 * and cancel_delayed_work() in wake_requests(). 3605 */ 3606 dout("%s rbd_dev %p queueing lock_dwork\n", __func__, rbd_dev); 3607 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0); 3608 prepare_to_wait_exclusive(&rbd_dev->lock_waitq, &wait, 3609 TASK_UNINTERRUPTIBLE); 3610 up_read(&rbd_dev->lock_rwsem); 3611 timeout = schedule_timeout(ceph_timeout_jiffies( 3612 rbd_dev->opts->lock_timeout)); 3613 down_read(&rbd_dev->lock_rwsem); 3614 if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) { 3615 ret = -EBLACKLISTED; 3616 break; 3617 } 3618 if (!timeout) { 3619 rbd_warn(rbd_dev, "timed out waiting for lock"); 3620 ret = -ETIMEDOUT; 3621 break; 3622 } 3623 } while (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED); 3624 3625 finish_wait(&rbd_dev->lock_waitq, &wait); 3626 return ret; 3627 } 3628 3629 static void rbd_queue_workfn(struct work_struct *work) 3630 { 3631 struct request *rq = blk_mq_rq_from_pdu(work); 3632 struct rbd_device *rbd_dev = rq->q->queuedata; 3633 struct rbd_img_request *img_request; 3634 struct ceph_snap_context *snapc = NULL; 3635 u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT; 3636 u64 length = blk_rq_bytes(rq); 3637 enum obj_operation_type op_type; 3638 u64 mapping_size; 3639 bool must_be_locked; 3640 int result; 3641 3642 switch (req_op(rq)) { 3643 case REQ_OP_DISCARD: 3644 case REQ_OP_WRITE_ZEROES: 3645 op_type = OBJ_OP_DISCARD; 3646 break; 3647 case REQ_OP_WRITE: 3648 op_type = OBJ_OP_WRITE; 3649 break; 3650 case REQ_OP_READ: 3651 op_type = OBJ_OP_READ; 3652 break; 3653 default: 3654 dout("%s: non-fs request type %d\n", __func__, req_op(rq)); 3655 result = -EIO; 3656 goto err; 3657 } 3658 3659 /* Ignore/skip any zero-length requests */ 3660 3661 if (!length) { 3662 dout("%s: zero-length request\n", __func__); 3663 result = 0; 3664 goto err_rq; 3665 } 3666 3667 rbd_assert(op_type == OBJ_OP_READ || 3668 rbd_dev->spec->snap_id == CEPH_NOSNAP); 3669 3670 /* 3671 * Quit early if the mapped snapshot no longer exists. It's 3672 * still possible the snapshot will have disappeared by the 3673 * time our request arrives at the osd, but there's no sense in 3674 * sending it if we already know. 3675 */ 3676 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) { 3677 dout("request for non-existent snapshot"); 3678 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP); 3679 result = -ENXIO; 3680 goto err_rq; 3681 } 3682 3683 if (offset && length > U64_MAX - offset + 1) { 3684 rbd_warn(rbd_dev, "bad request range (%llu~%llu)", offset, 3685 length); 3686 result = -EINVAL; 3687 goto err_rq; /* Shouldn't happen */ 3688 } 3689 3690 blk_mq_start_request(rq); 3691 3692 down_read(&rbd_dev->header_rwsem); 3693 mapping_size = rbd_dev->mapping.size; 3694 if (op_type != OBJ_OP_READ) { 3695 snapc = rbd_dev->header.snapc; 3696 ceph_get_snap_context(snapc); 3697 } 3698 up_read(&rbd_dev->header_rwsem); 3699 3700 if (offset + length > mapping_size) { 3701 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)", offset, 3702 length, mapping_size); 3703 result = -EIO; 3704 goto err_rq; 3705 } 3706 3707 must_be_locked = 3708 (rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK) && 3709 (op_type != OBJ_OP_READ || rbd_dev->opts->lock_on_read); 3710 if (must_be_locked) { 3711 down_read(&rbd_dev->lock_rwsem); 3712 result = rbd_wait_state_locked(rbd_dev, 3713 !rbd_dev->opts->exclusive); 3714 if (result) 3715 goto err_unlock; 3716 } 3717 3718 img_request = rbd_img_request_create(rbd_dev, op_type, snapc); 3719 if (!img_request) { 3720 result = -ENOMEM; 3721 goto err_unlock; 3722 } 3723 img_request->rq = rq; 3724 snapc = NULL; /* img_request consumes a ref */ 3725 3726 if (op_type == OBJ_OP_DISCARD) 3727 result = rbd_img_fill_nodata(img_request, offset, length); 3728 else 3729 result = rbd_img_fill_from_bio(img_request, offset, length, 3730 rq->bio); 3731 if (result) 3732 goto err_img_request; 3733 3734 rbd_img_request_submit(img_request); 3735 if (must_be_locked) 3736 up_read(&rbd_dev->lock_rwsem); 3737 return; 3738 3739 err_img_request: 3740 rbd_img_request_put(img_request); 3741 err_unlock: 3742 if (must_be_locked) 3743 up_read(&rbd_dev->lock_rwsem); 3744 err_rq: 3745 if (result) 3746 rbd_warn(rbd_dev, "%s %llx at %llx result %d", 3747 obj_op_name(op_type), length, offset, result); 3748 ceph_put_snap_context(snapc); 3749 err: 3750 blk_mq_end_request(rq, errno_to_blk_status(result)); 3751 } 3752 3753 static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx, 3754 const struct blk_mq_queue_data *bd) 3755 { 3756 struct request *rq = bd->rq; 3757 struct work_struct *work = blk_mq_rq_to_pdu(rq); 3758 3759 queue_work(rbd_wq, work); 3760 return BLK_STS_OK; 3761 } 3762 3763 static void rbd_free_disk(struct rbd_device *rbd_dev) 3764 { 3765 blk_cleanup_queue(rbd_dev->disk->queue); 3766 blk_mq_free_tag_set(&rbd_dev->tag_set); 3767 put_disk(rbd_dev->disk); 3768 rbd_dev->disk = NULL; 3769 } 3770 3771 static int rbd_obj_read_sync(struct rbd_device *rbd_dev, 3772 struct ceph_object_id *oid, 3773 struct ceph_object_locator *oloc, 3774 void *buf, int buf_len) 3775 3776 { 3777 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3778 struct ceph_osd_request *req; 3779 struct page **pages; 3780 int num_pages = calc_pages_for(0, buf_len); 3781 int ret; 3782 3783 req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL); 3784 if (!req) 3785 return -ENOMEM; 3786 3787 ceph_oid_copy(&req->r_base_oid, oid); 3788 ceph_oloc_copy(&req->r_base_oloc, oloc); 3789 req->r_flags = CEPH_OSD_FLAG_READ; 3790 3791 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL); 3792 if (IS_ERR(pages)) { 3793 ret = PTR_ERR(pages); 3794 goto out_req; 3795 } 3796 3797 osd_req_op_extent_init(req, 0, CEPH_OSD_OP_READ, 0, buf_len, 0, 0); 3798 osd_req_op_extent_osd_data_pages(req, 0, pages, buf_len, 0, false, 3799 true); 3800 3801 ret = ceph_osdc_alloc_messages(req, GFP_KERNEL); 3802 if (ret) 3803 goto out_req; 3804 3805 ceph_osdc_start_request(osdc, req, false); 3806 ret = ceph_osdc_wait_request(osdc, req); 3807 if (ret >= 0) 3808 ceph_copy_from_page_vector(pages, buf, 0, ret); 3809 3810 out_req: 3811 ceph_osdc_put_request(req); 3812 return ret; 3813 } 3814 3815 /* 3816 * Read the complete header for the given rbd device. On successful 3817 * return, the rbd_dev->header field will contain up-to-date 3818 * information about the image. 3819 */ 3820 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev) 3821 { 3822 struct rbd_image_header_ondisk *ondisk = NULL; 3823 u32 snap_count = 0; 3824 u64 names_size = 0; 3825 u32 want_count; 3826 int ret; 3827 3828 /* 3829 * The complete header will include an array of its 64-bit 3830 * snapshot ids, followed by the names of those snapshots as 3831 * a contiguous block of NUL-terminated strings. Note that 3832 * the number of snapshots could change by the time we read 3833 * it in, in which case we re-read it. 3834 */ 3835 do { 3836 size_t size; 3837 3838 kfree(ondisk); 3839 3840 size = sizeof (*ondisk); 3841 size += snap_count * sizeof (struct rbd_image_snap_ondisk); 3842 size += names_size; 3843 ondisk = kmalloc(size, GFP_KERNEL); 3844 if (!ondisk) 3845 return -ENOMEM; 3846 3847 ret = rbd_obj_read_sync(rbd_dev, &rbd_dev->header_oid, 3848 &rbd_dev->header_oloc, ondisk, size); 3849 if (ret < 0) 3850 goto out; 3851 if ((size_t)ret < size) { 3852 ret = -ENXIO; 3853 rbd_warn(rbd_dev, "short header read (want %zd got %d)", 3854 size, ret); 3855 goto out; 3856 } 3857 if (!rbd_dev_ondisk_valid(ondisk)) { 3858 ret = -ENXIO; 3859 rbd_warn(rbd_dev, "invalid header"); 3860 goto out; 3861 } 3862 3863 names_size = le64_to_cpu(ondisk->snap_names_len); 3864 want_count = snap_count; 3865 snap_count = le32_to_cpu(ondisk->snap_count); 3866 } while (snap_count != want_count); 3867 3868 ret = rbd_header_from_disk(rbd_dev, ondisk); 3869 out: 3870 kfree(ondisk); 3871 3872 return ret; 3873 } 3874 3875 /* 3876 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to 3877 * has disappeared from the (just updated) snapshot context. 3878 */ 3879 static void rbd_exists_validate(struct rbd_device *rbd_dev) 3880 { 3881 u64 snap_id; 3882 3883 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) 3884 return; 3885 3886 snap_id = rbd_dev->spec->snap_id; 3887 if (snap_id == CEPH_NOSNAP) 3888 return; 3889 3890 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX) 3891 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); 3892 } 3893 3894 static void rbd_dev_update_size(struct rbd_device *rbd_dev) 3895 { 3896 sector_t size; 3897 3898 /* 3899 * If EXISTS is not set, rbd_dev->disk may be NULL, so don't 3900 * try to update its size. If REMOVING is set, updating size 3901 * is just useless work since the device can't be opened. 3902 */ 3903 if (test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags) && 3904 !test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) { 3905 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE; 3906 dout("setting size to %llu sectors", (unsigned long long)size); 3907 set_capacity(rbd_dev->disk, size); 3908 revalidate_disk(rbd_dev->disk); 3909 } 3910 } 3911 3912 static int rbd_dev_refresh(struct rbd_device *rbd_dev) 3913 { 3914 u64 mapping_size; 3915 int ret; 3916 3917 down_write(&rbd_dev->header_rwsem); 3918 mapping_size = rbd_dev->mapping.size; 3919 3920 ret = rbd_dev_header_info(rbd_dev); 3921 if (ret) 3922 goto out; 3923 3924 /* 3925 * If there is a parent, see if it has disappeared due to the 3926 * mapped image getting flattened. 3927 */ 3928 if (rbd_dev->parent) { 3929 ret = rbd_dev_v2_parent_info(rbd_dev); 3930 if (ret) 3931 goto out; 3932 } 3933 3934 if (rbd_dev->spec->snap_id == CEPH_NOSNAP) { 3935 rbd_dev->mapping.size = rbd_dev->header.image_size; 3936 } else { 3937 /* validate mapped snapshot's EXISTS flag */ 3938 rbd_exists_validate(rbd_dev); 3939 } 3940 3941 out: 3942 up_write(&rbd_dev->header_rwsem); 3943 if (!ret && mapping_size != rbd_dev->mapping.size) 3944 rbd_dev_update_size(rbd_dev); 3945 3946 return ret; 3947 } 3948 3949 static int rbd_init_request(struct blk_mq_tag_set *set, struct request *rq, 3950 unsigned int hctx_idx, unsigned int numa_node) 3951 { 3952 struct work_struct *work = blk_mq_rq_to_pdu(rq); 3953 3954 INIT_WORK(work, rbd_queue_workfn); 3955 return 0; 3956 } 3957 3958 static const struct blk_mq_ops rbd_mq_ops = { 3959 .queue_rq = rbd_queue_rq, 3960 .init_request = rbd_init_request, 3961 }; 3962 3963 static int rbd_init_disk(struct rbd_device *rbd_dev) 3964 { 3965 struct gendisk *disk; 3966 struct request_queue *q; 3967 unsigned int objset_bytes = 3968 rbd_dev->layout.object_size * rbd_dev->layout.stripe_count; 3969 int err; 3970 3971 /* create gendisk info */ 3972 disk = alloc_disk(single_major ? 3973 (1 << RBD_SINGLE_MAJOR_PART_SHIFT) : 3974 RBD_MINORS_PER_MAJOR); 3975 if (!disk) 3976 return -ENOMEM; 3977 3978 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d", 3979 rbd_dev->dev_id); 3980 disk->major = rbd_dev->major; 3981 disk->first_minor = rbd_dev->minor; 3982 if (single_major) 3983 disk->flags |= GENHD_FL_EXT_DEVT; 3984 disk->fops = &rbd_bd_ops; 3985 disk->private_data = rbd_dev; 3986 3987 memset(&rbd_dev->tag_set, 0, sizeof(rbd_dev->tag_set)); 3988 rbd_dev->tag_set.ops = &rbd_mq_ops; 3989 rbd_dev->tag_set.queue_depth = rbd_dev->opts->queue_depth; 3990 rbd_dev->tag_set.numa_node = NUMA_NO_NODE; 3991 rbd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE; 3992 rbd_dev->tag_set.nr_hw_queues = 1; 3993 rbd_dev->tag_set.cmd_size = sizeof(struct work_struct); 3994 3995 err = blk_mq_alloc_tag_set(&rbd_dev->tag_set); 3996 if (err) 3997 goto out_disk; 3998 3999 q = blk_mq_init_queue(&rbd_dev->tag_set); 4000 if (IS_ERR(q)) { 4001 err = PTR_ERR(q); 4002 goto out_tag_set; 4003 } 4004 4005 blk_queue_flag_set(QUEUE_FLAG_NONROT, q); 4006 /* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */ 4007 4008 blk_queue_max_hw_sectors(q, objset_bytes >> SECTOR_SHIFT); 4009 q->limits.max_sectors = queue_max_hw_sectors(q); 4010 blk_queue_max_segments(q, USHRT_MAX); 4011 blk_queue_max_segment_size(q, UINT_MAX); 4012 blk_queue_io_min(q, objset_bytes); 4013 blk_queue_io_opt(q, objset_bytes); 4014 4015 if (rbd_dev->opts->trim) { 4016 blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); 4017 q->limits.discard_granularity = objset_bytes; 4018 blk_queue_max_discard_sectors(q, objset_bytes >> SECTOR_SHIFT); 4019 blk_queue_max_write_zeroes_sectors(q, objset_bytes >> SECTOR_SHIFT); 4020 } 4021 4022 if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC)) 4023 q->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES; 4024 4025 /* 4026 * disk_release() expects a queue ref from add_disk() and will 4027 * put it. Hold an extra ref until add_disk() is called. 4028 */ 4029 WARN_ON(!blk_get_queue(q)); 4030 disk->queue = q; 4031 q->queuedata = rbd_dev; 4032 4033 rbd_dev->disk = disk; 4034 4035 return 0; 4036 out_tag_set: 4037 blk_mq_free_tag_set(&rbd_dev->tag_set); 4038 out_disk: 4039 put_disk(disk); 4040 return err; 4041 } 4042 4043 /* 4044 sysfs 4045 */ 4046 4047 static struct rbd_device *dev_to_rbd_dev(struct device *dev) 4048 { 4049 return container_of(dev, struct rbd_device, dev); 4050 } 4051 4052 static ssize_t rbd_size_show(struct device *dev, 4053 struct device_attribute *attr, char *buf) 4054 { 4055 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4056 4057 return sprintf(buf, "%llu\n", 4058 (unsigned long long)rbd_dev->mapping.size); 4059 } 4060 4061 /* 4062 * Note this shows the features for whatever's mapped, which is not 4063 * necessarily the base image. 4064 */ 4065 static ssize_t rbd_features_show(struct device *dev, 4066 struct device_attribute *attr, char *buf) 4067 { 4068 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4069 4070 return sprintf(buf, "0x%016llx\n", 4071 (unsigned long long)rbd_dev->mapping.features); 4072 } 4073 4074 static ssize_t rbd_major_show(struct device *dev, 4075 struct device_attribute *attr, char *buf) 4076 { 4077 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4078 4079 if (rbd_dev->major) 4080 return sprintf(buf, "%d\n", rbd_dev->major); 4081 4082 return sprintf(buf, "(none)\n"); 4083 } 4084 4085 static ssize_t rbd_minor_show(struct device *dev, 4086 struct device_attribute *attr, char *buf) 4087 { 4088 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4089 4090 return sprintf(buf, "%d\n", rbd_dev->minor); 4091 } 4092 4093 static ssize_t rbd_client_addr_show(struct device *dev, 4094 struct device_attribute *attr, char *buf) 4095 { 4096 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4097 struct ceph_entity_addr *client_addr = 4098 ceph_client_addr(rbd_dev->rbd_client->client); 4099 4100 return sprintf(buf, "%pISpc/%u\n", &client_addr->in_addr, 4101 le32_to_cpu(client_addr->nonce)); 4102 } 4103 4104 static ssize_t rbd_client_id_show(struct device *dev, 4105 struct device_attribute *attr, char *buf) 4106 { 4107 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4108 4109 return sprintf(buf, "client%lld\n", 4110 ceph_client_gid(rbd_dev->rbd_client->client)); 4111 } 4112 4113 static ssize_t rbd_cluster_fsid_show(struct device *dev, 4114 struct device_attribute *attr, char *buf) 4115 { 4116 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4117 4118 return sprintf(buf, "%pU\n", &rbd_dev->rbd_client->client->fsid); 4119 } 4120 4121 static ssize_t rbd_config_info_show(struct device *dev, 4122 struct device_attribute *attr, char *buf) 4123 { 4124 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4125 4126 return sprintf(buf, "%s\n", rbd_dev->config_info); 4127 } 4128 4129 static ssize_t rbd_pool_show(struct device *dev, 4130 struct device_attribute *attr, char *buf) 4131 { 4132 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4133 4134 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name); 4135 } 4136 4137 static ssize_t rbd_pool_id_show(struct device *dev, 4138 struct device_attribute *attr, char *buf) 4139 { 4140 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4141 4142 return sprintf(buf, "%llu\n", 4143 (unsigned long long) rbd_dev->spec->pool_id); 4144 } 4145 4146 static ssize_t rbd_pool_ns_show(struct device *dev, 4147 struct device_attribute *attr, char *buf) 4148 { 4149 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4150 4151 return sprintf(buf, "%s\n", rbd_dev->spec->pool_ns ?: ""); 4152 } 4153 4154 static ssize_t rbd_name_show(struct device *dev, 4155 struct device_attribute *attr, char *buf) 4156 { 4157 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4158 4159 if (rbd_dev->spec->image_name) 4160 return sprintf(buf, "%s\n", rbd_dev->spec->image_name); 4161 4162 return sprintf(buf, "(unknown)\n"); 4163 } 4164 4165 static ssize_t rbd_image_id_show(struct device *dev, 4166 struct device_attribute *attr, char *buf) 4167 { 4168 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4169 4170 return sprintf(buf, "%s\n", rbd_dev->spec->image_id); 4171 } 4172 4173 /* 4174 * Shows the name of the currently-mapped snapshot (or 4175 * RBD_SNAP_HEAD_NAME for the base image). 4176 */ 4177 static ssize_t rbd_snap_show(struct device *dev, 4178 struct device_attribute *attr, 4179 char *buf) 4180 { 4181 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4182 4183 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name); 4184 } 4185 4186 static ssize_t rbd_snap_id_show(struct device *dev, 4187 struct device_attribute *attr, char *buf) 4188 { 4189 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4190 4191 return sprintf(buf, "%llu\n", rbd_dev->spec->snap_id); 4192 } 4193 4194 /* 4195 * For a v2 image, shows the chain of parent images, separated by empty 4196 * lines. For v1 images or if there is no parent, shows "(no parent 4197 * image)". 4198 */ 4199 static ssize_t rbd_parent_show(struct device *dev, 4200 struct device_attribute *attr, 4201 char *buf) 4202 { 4203 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4204 ssize_t count = 0; 4205 4206 if (!rbd_dev->parent) 4207 return sprintf(buf, "(no parent image)\n"); 4208 4209 for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) { 4210 struct rbd_spec *spec = rbd_dev->parent_spec; 4211 4212 count += sprintf(&buf[count], "%s" 4213 "pool_id %llu\npool_name %s\n" 4214 "pool_ns %s\n" 4215 "image_id %s\nimage_name %s\n" 4216 "snap_id %llu\nsnap_name %s\n" 4217 "overlap %llu\n", 4218 !count ? "" : "\n", /* first? */ 4219 spec->pool_id, spec->pool_name, 4220 spec->pool_ns ?: "", 4221 spec->image_id, spec->image_name ?: "(unknown)", 4222 spec->snap_id, spec->snap_name, 4223 rbd_dev->parent_overlap); 4224 } 4225 4226 return count; 4227 } 4228 4229 static ssize_t rbd_image_refresh(struct device *dev, 4230 struct device_attribute *attr, 4231 const char *buf, 4232 size_t size) 4233 { 4234 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4235 int ret; 4236 4237 ret = rbd_dev_refresh(rbd_dev); 4238 if (ret) 4239 return ret; 4240 4241 return size; 4242 } 4243 4244 static DEVICE_ATTR(size, 0444, rbd_size_show, NULL); 4245 static DEVICE_ATTR(features, 0444, rbd_features_show, NULL); 4246 static DEVICE_ATTR(major, 0444, rbd_major_show, NULL); 4247 static DEVICE_ATTR(minor, 0444, rbd_minor_show, NULL); 4248 static DEVICE_ATTR(client_addr, 0444, rbd_client_addr_show, NULL); 4249 static DEVICE_ATTR(client_id, 0444, rbd_client_id_show, NULL); 4250 static DEVICE_ATTR(cluster_fsid, 0444, rbd_cluster_fsid_show, NULL); 4251 static DEVICE_ATTR(config_info, 0400, rbd_config_info_show, NULL); 4252 static DEVICE_ATTR(pool, 0444, rbd_pool_show, NULL); 4253 static DEVICE_ATTR(pool_id, 0444, rbd_pool_id_show, NULL); 4254 static DEVICE_ATTR(pool_ns, 0444, rbd_pool_ns_show, NULL); 4255 static DEVICE_ATTR(name, 0444, rbd_name_show, NULL); 4256 static DEVICE_ATTR(image_id, 0444, rbd_image_id_show, NULL); 4257 static DEVICE_ATTR(refresh, 0200, NULL, rbd_image_refresh); 4258 static DEVICE_ATTR(current_snap, 0444, rbd_snap_show, NULL); 4259 static DEVICE_ATTR(snap_id, 0444, rbd_snap_id_show, NULL); 4260 static DEVICE_ATTR(parent, 0444, rbd_parent_show, NULL); 4261 4262 static struct attribute *rbd_attrs[] = { 4263 &dev_attr_size.attr, 4264 &dev_attr_features.attr, 4265 &dev_attr_major.attr, 4266 &dev_attr_minor.attr, 4267 &dev_attr_client_addr.attr, 4268 &dev_attr_client_id.attr, 4269 &dev_attr_cluster_fsid.attr, 4270 &dev_attr_config_info.attr, 4271 &dev_attr_pool.attr, 4272 &dev_attr_pool_id.attr, 4273 &dev_attr_pool_ns.attr, 4274 &dev_attr_name.attr, 4275 &dev_attr_image_id.attr, 4276 &dev_attr_current_snap.attr, 4277 &dev_attr_snap_id.attr, 4278 &dev_attr_parent.attr, 4279 &dev_attr_refresh.attr, 4280 NULL 4281 }; 4282 4283 static struct attribute_group rbd_attr_group = { 4284 .attrs = rbd_attrs, 4285 }; 4286 4287 static const struct attribute_group *rbd_attr_groups[] = { 4288 &rbd_attr_group, 4289 NULL 4290 }; 4291 4292 static void rbd_dev_release(struct device *dev); 4293 4294 static const struct device_type rbd_device_type = { 4295 .name = "rbd", 4296 .groups = rbd_attr_groups, 4297 .release = rbd_dev_release, 4298 }; 4299 4300 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec) 4301 { 4302 kref_get(&spec->kref); 4303 4304 return spec; 4305 } 4306 4307 static void rbd_spec_free(struct kref *kref); 4308 static void rbd_spec_put(struct rbd_spec *spec) 4309 { 4310 if (spec) 4311 kref_put(&spec->kref, rbd_spec_free); 4312 } 4313 4314 static struct rbd_spec *rbd_spec_alloc(void) 4315 { 4316 struct rbd_spec *spec; 4317 4318 spec = kzalloc(sizeof (*spec), GFP_KERNEL); 4319 if (!spec) 4320 return NULL; 4321 4322 spec->pool_id = CEPH_NOPOOL; 4323 spec->snap_id = CEPH_NOSNAP; 4324 kref_init(&spec->kref); 4325 4326 return spec; 4327 } 4328 4329 static void rbd_spec_free(struct kref *kref) 4330 { 4331 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref); 4332 4333 kfree(spec->pool_name); 4334 kfree(spec->pool_ns); 4335 kfree(spec->image_id); 4336 kfree(spec->image_name); 4337 kfree(spec->snap_name); 4338 kfree(spec); 4339 } 4340 4341 static void rbd_dev_free(struct rbd_device *rbd_dev) 4342 { 4343 WARN_ON(rbd_dev->watch_state != RBD_WATCH_STATE_UNREGISTERED); 4344 WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_UNLOCKED); 4345 4346 ceph_oid_destroy(&rbd_dev->header_oid); 4347 ceph_oloc_destroy(&rbd_dev->header_oloc); 4348 kfree(rbd_dev->config_info); 4349 4350 rbd_put_client(rbd_dev->rbd_client); 4351 rbd_spec_put(rbd_dev->spec); 4352 kfree(rbd_dev->opts); 4353 kfree(rbd_dev); 4354 } 4355 4356 static void rbd_dev_release(struct device *dev) 4357 { 4358 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 4359 bool need_put = !!rbd_dev->opts; 4360 4361 if (need_put) { 4362 destroy_workqueue(rbd_dev->task_wq); 4363 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); 4364 } 4365 4366 rbd_dev_free(rbd_dev); 4367 4368 /* 4369 * This is racy, but way better than putting module outside of 4370 * the release callback. The race window is pretty small, so 4371 * doing something similar to dm (dm-builtin.c) is overkill. 4372 */ 4373 if (need_put) 4374 module_put(THIS_MODULE); 4375 } 4376 4377 static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc, 4378 struct rbd_spec *spec) 4379 { 4380 struct rbd_device *rbd_dev; 4381 4382 rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL); 4383 if (!rbd_dev) 4384 return NULL; 4385 4386 spin_lock_init(&rbd_dev->lock); 4387 INIT_LIST_HEAD(&rbd_dev->node); 4388 init_rwsem(&rbd_dev->header_rwsem); 4389 4390 rbd_dev->header.data_pool_id = CEPH_NOPOOL; 4391 ceph_oid_init(&rbd_dev->header_oid); 4392 rbd_dev->header_oloc.pool = spec->pool_id; 4393 if (spec->pool_ns) { 4394 WARN_ON(!*spec->pool_ns); 4395 rbd_dev->header_oloc.pool_ns = 4396 ceph_find_or_create_string(spec->pool_ns, 4397 strlen(spec->pool_ns)); 4398 } 4399 4400 mutex_init(&rbd_dev->watch_mutex); 4401 rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED; 4402 INIT_DELAYED_WORK(&rbd_dev->watch_dwork, rbd_reregister_watch); 4403 4404 init_rwsem(&rbd_dev->lock_rwsem); 4405 rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED; 4406 INIT_WORK(&rbd_dev->acquired_lock_work, rbd_notify_acquired_lock); 4407 INIT_WORK(&rbd_dev->released_lock_work, rbd_notify_released_lock); 4408 INIT_DELAYED_WORK(&rbd_dev->lock_dwork, rbd_acquire_lock); 4409 INIT_WORK(&rbd_dev->unlock_work, rbd_release_lock_work); 4410 init_waitqueue_head(&rbd_dev->lock_waitq); 4411 4412 rbd_dev->dev.bus = &rbd_bus_type; 4413 rbd_dev->dev.type = &rbd_device_type; 4414 rbd_dev->dev.parent = &rbd_root_dev; 4415 device_initialize(&rbd_dev->dev); 4416 4417 rbd_dev->rbd_client = rbdc; 4418 rbd_dev->spec = spec; 4419 4420 return rbd_dev; 4421 } 4422 4423 /* 4424 * Create a mapping rbd_dev. 4425 */ 4426 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, 4427 struct rbd_spec *spec, 4428 struct rbd_options *opts) 4429 { 4430 struct rbd_device *rbd_dev; 4431 4432 rbd_dev = __rbd_dev_create(rbdc, spec); 4433 if (!rbd_dev) 4434 return NULL; 4435 4436 rbd_dev->opts = opts; 4437 4438 /* get an id and fill in device name */ 4439 rbd_dev->dev_id = ida_simple_get(&rbd_dev_id_ida, 0, 4440 minor_to_rbd_dev_id(1 << MINORBITS), 4441 GFP_KERNEL); 4442 if (rbd_dev->dev_id < 0) 4443 goto fail_rbd_dev; 4444 4445 sprintf(rbd_dev->name, RBD_DRV_NAME "%d", rbd_dev->dev_id); 4446 rbd_dev->task_wq = alloc_ordered_workqueue("%s-tasks", WQ_MEM_RECLAIM, 4447 rbd_dev->name); 4448 if (!rbd_dev->task_wq) 4449 goto fail_dev_id; 4450 4451 /* we have a ref from do_rbd_add() */ 4452 __module_get(THIS_MODULE); 4453 4454 dout("%s rbd_dev %p dev_id %d\n", __func__, rbd_dev, rbd_dev->dev_id); 4455 return rbd_dev; 4456 4457 fail_dev_id: 4458 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); 4459 fail_rbd_dev: 4460 rbd_dev_free(rbd_dev); 4461 return NULL; 4462 } 4463 4464 static void rbd_dev_destroy(struct rbd_device *rbd_dev) 4465 { 4466 if (rbd_dev) 4467 put_device(&rbd_dev->dev); 4468 } 4469 4470 /* 4471 * Get the size and object order for an image snapshot, or if 4472 * snap_id is CEPH_NOSNAP, gets this information for the base 4473 * image. 4474 */ 4475 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 4476 u8 *order, u64 *snap_size) 4477 { 4478 __le64 snapid = cpu_to_le64(snap_id); 4479 int ret; 4480 struct { 4481 u8 order; 4482 __le64 size; 4483 } __attribute__ ((packed)) size_buf = { 0 }; 4484 4485 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 4486 &rbd_dev->header_oloc, "get_size", 4487 &snapid, sizeof(snapid), 4488 &size_buf, sizeof(size_buf)); 4489 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4490 if (ret < 0) 4491 return ret; 4492 if (ret < sizeof (size_buf)) 4493 return -ERANGE; 4494 4495 if (order) { 4496 *order = size_buf.order; 4497 dout(" order %u", (unsigned int)*order); 4498 } 4499 *snap_size = le64_to_cpu(size_buf.size); 4500 4501 dout(" snap_id 0x%016llx snap_size = %llu\n", 4502 (unsigned long long)snap_id, 4503 (unsigned long long)*snap_size); 4504 4505 return 0; 4506 } 4507 4508 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev) 4509 { 4510 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP, 4511 &rbd_dev->header.obj_order, 4512 &rbd_dev->header.image_size); 4513 } 4514 4515 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev) 4516 { 4517 void *reply_buf; 4518 int ret; 4519 void *p; 4520 4521 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL); 4522 if (!reply_buf) 4523 return -ENOMEM; 4524 4525 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 4526 &rbd_dev->header_oloc, "get_object_prefix", 4527 NULL, 0, reply_buf, RBD_OBJ_PREFIX_LEN_MAX); 4528 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4529 if (ret < 0) 4530 goto out; 4531 4532 p = reply_buf; 4533 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p, 4534 p + ret, NULL, GFP_NOIO); 4535 ret = 0; 4536 4537 if (IS_ERR(rbd_dev->header.object_prefix)) { 4538 ret = PTR_ERR(rbd_dev->header.object_prefix); 4539 rbd_dev->header.object_prefix = NULL; 4540 } else { 4541 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix); 4542 } 4543 out: 4544 kfree(reply_buf); 4545 4546 return ret; 4547 } 4548 4549 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, 4550 u64 *snap_features) 4551 { 4552 __le64 snapid = cpu_to_le64(snap_id); 4553 struct { 4554 __le64 features; 4555 __le64 incompat; 4556 } __attribute__ ((packed)) features_buf = { 0 }; 4557 u64 unsup; 4558 int ret; 4559 4560 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 4561 &rbd_dev->header_oloc, "get_features", 4562 &snapid, sizeof(snapid), 4563 &features_buf, sizeof(features_buf)); 4564 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4565 if (ret < 0) 4566 return ret; 4567 if (ret < sizeof (features_buf)) 4568 return -ERANGE; 4569 4570 unsup = le64_to_cpu(features_buf.incompat) & ~RBD_FEATURES_SUPPORTED; 4571 if (unsup) { 4572 rbd_warn(rbd_dev, "image uses unsupported features: 0x%llx", 4573 unsup); 4574 return -ENXIO; 4575 } 4576 4577 *snap_features = le64_to_cpu(features_buf.features); 4578 4579 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n", 4580 (unsigned long long)snap_id, 4581 (unsigned long long)*snap_features, 4582 (unsigned long long)le64_to_cpu(features_buf.incompat)); 4583 4584 return 0; 4585 } 4586 4587 static int rbd_dev_v2_features(struct rbd_device *rbd_dev) 4588 { 4589 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP, 4590 &rbd_dev->header.features); 4591 } 4592 4593 struct parent_image_info { 4594 u64 pool_id; 4595 const char *pool_ns; 4596 const char *image_id; 4597 u64 snap_id; 4598 4599 bool has_overlap; 4600 u64 overlap; 4601 }; 4602 4603 /* 4604 * The caller is responsible for @pii. 4605 */ 4606 static int decode_parent_image_spec(void **p, void *end, 4607 struct parent_image_info *pii) 4608 { 4609 u8 struct_v; 4610 u32 struct_len; 4611 int ret; 4612 4613 ret = ceph_start_decoding(p, end, 1, "ParentImageSpec", 4614 &struct_v, &struct_len); 4615 if (ret) 4616 return ret; 4617 4618 ceph_decode_64_safe(p, end, pii->pool_id, e_inval); 4619 pii->pool_ns = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL); 4620 if (IS_ERR(pii->pool_ns)) { 4621 ret = PTR_ERR(pii->pool_ns); 4622 pii->pool_ns = NULL; 4623 return ret; 4624 } 4625 pii->image_id = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL); 4626 if (IS_ERR(pii->image_id)) { 4627 ret = PTR_ERR(pii->image_id); 4628 pii->image_id = NULL; 4629 return ret; 4630 } 4631 ceph_decode_64_safe(p, end, pii->snap_id, e_inval); 4632 return 0; 4633 4634 e_inval: 4635 return -EINVAL; 4636 } 4637 4638 static int __get_parent_info(struct rbd_device *rbd_dev, 4639 struct page *req_page, 4640 struct page *reply_page, 4641 struct parent_image_info *pii) 4642 { 4643 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4644 size_t reply_len = PAGE_SIZE; 4645 void *p, *end; 4646 int ret; 4647 4648 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 4649 "rbd", "parent_get", CEPH_OSD_FLAG_READ, 4650 req_page, sizeof(u64), reply_page, &reply_len); 4651 if (ret) 4652 return ret == -EOPNOTSUPP ? 1 : ret; 4653 4654 p = page_address(reply_page); 4655 end = p + reply_len; 4656 ret = decode_parent_image_spec(&p, end, pii); 4657 if (ret) 4658 return ret; 4659 4660 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 4661 "rbd", "parent_overlap_get", CEPH_OSD_FLAG_READ, 4662 req_page, sizeof(u64), reply_page, &reply_len); 4663 if (ret) 4664 return ret; 4665 4666 p = page_address(reply_page); 4667 end = p + reply_len; 4668 ceph_decode_8_safe(&p, end, pii->has_overlap, e_inval); 4669 if (pii->has_overlap) 4670 ceph_decode_64_safe(&p, end, pii->overlap, e_inval); 4671 4672 return 0; 4673 4674 e_inval: 4675 return -EINVAL; 4676 } 4677 4678 /* 4679 * The caller is responsible for @pii. 4680 */ 4681 static int __get_parent_info_legacy(struct rbd_device *rbd_dev, 4682 struct page *req_page, 4683 struct page *reply_page, 4684 struct parent_image_info *pii) 4685 { 4686 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4687 size_t reply_len = PAGE_SIZE; 4688 void *p, *end; 4689 int ret; 4690 4691 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 4692 "rbd", "get_parent", CEPH_OSD_FLAG_READ, 4693 req_page, sizeof(u64), reply_page, &reply_len); 4694 if (ret) 4695 return ret; 4696 4697 p = page_address(reply_page); 4698 end = p + reply_len; 4699 ceph_decode_64_safe(&p, end, pii->pool_id, e_inval); 4700 pii->image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL); 4701 if (IS_ERR(pii->image_id)) { 4702 ret = PTR_ERR(pii->image_id); 4703 pii->image_id = NULL; 4704 return ret; 4705 } 4706 ceph_decode_64_safe(&p, end, pii->snap_id, e_inval); 4707 pii->has_overlap = true; 4708 ceph_decode_64_safe(&p, end, pii->overlap, e_inval); 4709 4710 return 0; 4711 4712 e_inval: 4713 return -EINVAL; 4714 } 4715 4716 static int get_parent_info(struct rbd_device *rbd_dev, 4717 struct parent_image_info *pii) 4718 { 4719 struct page *req_page, *reply_page; 4720 void *p; 4721 int ret; 4722 4723 req_page = alloc_page(GFP_KERNEL); 4724 if (!req_page) 4725 return -ENOMEM; 4726 4727 reply_page = alloc_page(GFP_KERNEL); 4728 if (!reply_page) { 4729 __free_page(req_page); 4730 return -ENOMEM; 4731 } 4732 4733 p = page_address(req_page); 4734 ceph_encode_64(&p, rbd_dev->spec->snap_id); 4735 ret = __get_parent_info(rbd_dev, req_page, reply_page, pii); 4736 if (ret > 0) 4737 ret = __get_parent_info_legacy(rbd_dev, req_page, reply_page, 4738 pii); 4739 4740 __free_page(req_page); 4741 __free_page(reply_page); 4742 return ret; 4743 } 4744 4745 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev) 4746 { 4747 struct rbd_spec *parent_spec; 4748 struct parent_image_info pii = { 0 }; 4749 int ret; 4750 4751 parent_spec = rbd_spec_alloc(); 4752 if (!parent_spec) 4753 return -ENOMEM; 4754 4755 ret = get_parent_info(rbd_dev, &pii); 4756 if (ret) 4757 goto out_err; 4758 4759 dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n", 4760 __func__, pii.pool_id, pii.pool_ns, pii.image_id, pii.snap_id, 4761 pii.has_overlap, pii.overlap); 4762 4763 if (pii.pool_id == CEPH_NOPOOL || !pii.has_overlap) { 4764 /* 4765 * Either the parent never existed, or we have 4766 * record of it but the image got flattened so it no 4767 * longer has a parent. When the parent of a 4768 * layered image disappears we immediately set the 4769 * overlap to 0. The effect of this is that all new 4770 * requests will be treated as if the image had no 4771 * parent. 4772 * 4773 * If !pii.has_overlap, the parent image spec is not 4774 * applicable. It's there to avoid duplication in each 4775 * snapshot record. 4776 */ 4777 if (rbd_dev->parent_overlap) { 4778 rbd_dev->parent_overlap = 0; 4779 rbd_dev_parent_put(rbd_dev); 4780 pr_info("%s: clone image has been flattened\n", 4781 rbd_dev->disk->disk_name); 4782 } 4783 4784 goto out; /* No parent? No problem. */ 4785 } 4786 4787 /* The ceph file layout needs to fit pool id in 32 bits */ 4788 4789 ret = -EIO; 4790 if (pii.pool_id > (u64)U32_MAX) { 4791 rbd_warn(NULL, "parent pool id too large (%llu > %u)", 4792 (unsigned long long)pii.pool_id, U32_MAX); 4793 goto out_err; 4794 } 4795 4796 /* 4797 * The parent won't change (except when the clone is 4798 * flattened, already handled that). So we only need to 4799 * record the parent spec we have not already done so. 4800 */ 4801 if (!rbd_dev->parent_spec) { 4802 parent_spec->pool_id = pii.pool_id; 4803 if (pii.pool_ns && *pii.pool_ns) { 4804 parent_spec->pool_ns = pii.pool_ns; 4805 pii.pool_ns = NULL; 4806 } 4807 parent_spec->image_id = pii.image_id; 4808 pii.image_id = NULL; 4809 parent_spec->snap_id = pii.snap_id; 4810 4811 rbd_dev->parent_spec = parent_spec; 4812 parent_spec = NULL; /* rbd_dev now owns this */ 4813 } 4814 4815 /* 4816 * We always update the parent overlap. If it's zero we issue 4817 * a warning, as we will proceed as if there was no parent. 4818 */ 4819 if (!pii.overlap) { 4820 if (parent_spec) { 4821 /* refresh, careful to warn just once */ 4822 if (rbd_dev->parent_overlap) 4823 rbd_warn(rbd_dev, 4824 "clone now standalone (overlap became 0)"); 4825 } else { 4826 /* initial probe */ 4827 rbd_warn(rbd_dev, "clone is standalone (overlap 0)"); 4828 } 4829 } 4830 rbd_dev->parent_overlap = pii.overlap; 4831 4832 out: 4833 ret = 0; 4834 out_err: 4835 kfree(pii.pool_ns); 4836 kfree(pii.image_id); 4837 rbd_spec_put(parent_spec); 4838 return ret; 4839 } 4840 4841 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev) 4842 { 4843 struct { 4844 __le64 stripe_unit; 4845 __le64 stripe_count; 4846 } __attribute__ ((packed)) striping_info_buf = { 0 }; 4847 size_t size = sizeof (striping_info_buf); 4848 void *p; 4849 int ret; 4850 4851 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 4852 &rbd_dev->header_oloc, "get_stripe_unit_count", 4853 NULL, 0, &striping_info_buf, size); 4854 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4855 if (ret < 0) 4856 return ret; 4857 if (ret < size) 4858 return -ERANGE; 4859 4860 p = &striping_info_buf; 4861 rbd_dev->header.stripe_unit = ceph_decode_64(&p); 4862 rbd_dev->header.stripe_count = ceph_decode_64(&p); 4863 return 0; 4864 } 4865 4866 static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev) 4867 { 4868 __le64 data_pool_id; 4869 int ret; 4870 4871 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 4872 &rbd_dev->header_oloc, "get_data_pool", 4873 NULL, 0, &data_pool_id, sizeof(data_pool_id)); 4874 if (ret < 0) 4875 return ret; 4876 if (ret < sizeof(data_pool_id)) 4877 return -EBADMSG; 4878 4879 rbd_dev->header.data_pool_id = le64_to_cpu(data_pool_id); 4880 WARN_ON(rbd_dev->header.data_pool_id == CEPH_NOPOOL); 4881 return 0; 4882 } 4883 4884 static char *rbd_dev_image_name(struct rbd_device *rbd_dev) 4885 { 4886 CEPH_DEFINE_OID_ONSTACK(oid); 4887 size_t image_id_size; 4888 char *image_id; 4889 void *p; 4890 void *end; 4891 size_t size; 4892 void *reply_buf = NULL; 4893 size_t len = 0; 4894 char *image_name = NULL; 4895 int ret; 4896 4897 rbd_assert(!rbd_dev->spec->image_name); 4898 4899 len = strlen(rbd_dev->spec->image_id); 4900 image_id_size = sizeof (__le32) + len; 4901 image_id = kmalloc(image_id_size, GFP_KERNEL); 4902 if (!image_id) 4903 return NULL; 4904 4905 p = image_id; 4906 end = image_id + image_id_size; 4907 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len); 4908 4909 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX; 4910 reply_buf = kmalloc(size, GFP_KERNEL); 4911 if (!reply_buf) 4912 goto out; 4913 4914 ceph_oid_printf(&oid, "%s", RBD_DIRECTORY); 4915 ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc, 4916 "dir_get_name", image_id, image_id_size, 4917 reply_buf, size); 4918 if (ret < 0) 4919 goto out; 4920 p = reply_buf; 4921 end = reply_buf + ret; 4922 4923 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL); 4924 if (IS_ERR(image_name)) 4925 image_name = NULL; 4926 else 4927 dout("%s: name is %s len is %zd\n", __func__, image_name, len); 4928 out: 4929 kfree(reply_buf); 4930 kfree(image_id); 4931 4932 return image_name; 4933 } 4934 4935 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 4936 { 4937 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 4938 const char *snap_name; 4939 u32 which = 0; 4940 4941 /* Skip over names until we find the one we are looking for */ 4942 4943 snap_name = rbd_dev->header.snap_names; 4944 while (which < snapc->num_snaps) { 4945 if (!strcmp(name, snap_name)) 4946 return snapc->snaps[which]; 4947 snap_name += strlen(snap_name) + 1; 4948 which++; 4949 } 4950 return CEPH_NOSNAP; 4951 } 4952 4953 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 4954 { 4955 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 4956 u32 which; 4957 bool found = false; 4958 u64 snap_id; 4959 4960 for (which = 0; !found && which < snapc->num_snaps; which++) { 4961 const char *snap_name; 4962 4963 snap_id = snapc->snaps[which]; 4964 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id); 4965 if (IS_ERR(snap_name)) { 4966 /* ignore no-longer existing snapshots */ 4967 if (PTR_ERR(snap_name) == -ENOENT) 4968 continue; 4969 else 4970 break; 4971 } 4972 found = !strcmp(name, snap_name); 4973 kfree(snap_name); 4974 } 4975 return found ? snap_id : CEPH_NOSNAP; 4976 } 4977 4978 /* 4979 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if 4980 * no snapshot by that name is found, or if an error occurs. 4981 */ 4982 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 4983 { 4984 if (rbd_dev->image_format == 1) 4985 return rbd_v1_snap_id_by_name(rbd_dev, name); 4986 4987 return rbd_v2_snap_id_by_name(rbd_dev, name); 4988 } 4989 4990 /* 4991 * An image being mapped will have everything but the snap id. 4992 */ 4993 static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev) 4994 { 4995 struct rbd_spec *spec = rbd_dev->spec; 4996 4997 rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name); 4998 rbd_assert(spec->image_id && spec->image_name); 4999 rbd_assert(spec->snap_name); 5000 5001 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) { 5002 u64 snap_id; 5003 5004 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name); 5005 if (snap_id == CEPH_NOSNAP) 5006 return -ENOENT; 5007 5008 spec->snap_id = snap_id; 5009 } else { 5010 spec->snap_id = CEPH_NOSNAP; 5011 } 5012 5013 return 0; 5014 } 5015 5016 /* 5017 * A parent image will have all ids but none of the names. 5018 * 5019 * All names in an rbd spec are dynamically allocated. It's OK if we 5020 * can't figure out the name for an image id. 5021 */ 5022 static int rbd_spec_fill_names(struct rbd_device *rbd_dev) 5023 { 5024 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 5025 struct rbd_spec *spec = rbd_dev->spec; 5026 const char *pool_name; 5027 const char *image_name; 5028 const char *snap_name; 5029 int ret; 5030 5031 rbd_assert(spec->pool_id != CEPH_NOPOOL); 5032 rbd_assert(spec->image_id); 5033 rbd_assert(spec->snap_id != CEPH_NOSNAP); 5034 5035 /* Get the pool name; we have to make our own copy of this */ 5036 5037 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id); 5038 if (!pool_name) { 5039 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id); 5040 return -EIO; 5041 } 5042 pool_name = kstrdup(pool_name, GFP_KERNEL); 5043 if (!pool_name) 5044 return -ENOMEM; 5045 5046 /* Fetch the image name; tolerate failure here */ 5047 5048 image_name = rbd_dev_image_name(rbd_dev); 5049 if (!image_name) 5050 rbd_warn(rbd_dev, "unable to get image name"); 5051 5052 /* Fetch the snapshot name */ 5053 5054 snap_name = rbd_snap_name(rbd_dev, spec->snap_id); 5055 if (IS_ERR(snap_name)) { 5056 ret = PTR_ERR(snap_name); 5057 goto out_err; 5058 } 5059 5060 spec->pool_name = pool_name; 5061 spec->image_name = image_name; 5062 spec->snap_name = snap_name; 5063 5064 return 0; 5065 5066 out_err: 5067 kfree(image_name); 5068 kfree(pool_name); 5069 return ret; 5070 } 5071 5072 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev) 5073 { 5074 size_t size; 5075 int ret; 5076 void *reply_buf; 5077 void *p; 5078 void *end; 5079 u64 seq; 5080 u32 snap_count; 5081 struct ceph_snap_context *snapc; 5082 u32 i; 5083 5084 /* 5085 * We'll need room for the seq value (maximum snapshot id), 5086 * snapshot count, and array of that many snapshot ids. 5087 * For now we have a fixed upper limit on the number we're 5088 * prepared to receive. 5089 */ 5090 size = sizeof (__le64) + sizeof (__le32) + 5091 RBD_MAX_SNAP_COUNT * sizeof (__le64); 5092 reply_buf = kzalloc(size, GFP_KERNEL); 5093 if (!reply_buf) 5094 return -ENOMEM; 5095 5096 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 5097 &rbd_dev->header_oloc, "get_snapcontext", 5098 NULL, 0, reply_buf, size); 5099 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 5100 if (ret < 0) 5101 goto out; 5102 5103 p = reply_buf; 5104 end = reply_buf + ret; 5105 ret = -ERANGE; 5106 ceph_decode_64_safe(&p, end, seq, out); 5107 ceph_decode_32_safe(&p, end, snap_count, out); 5108 5109 /* 5110 * Make sure the reported number of snapshot ids wouldn't go 5111 * beyond the end of our buffer. But before checking that, 5112 * make sure the computed size of the snapshot context we 5113 * allocate is representable in a size_t. 5114 */ 5115 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context)) 5116 / sizeof (u64)) { 5117 ret = -EINVAL; 5118 goto out; 5119 } 5120 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64))) 5121 goto out; 5122 ret = 0; 5123 5124 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); 5125 if (!snapc) { 5126 ret = -ENOMEM; 5127 goto out; 5128 } 5129 snapc->seq = seq; 5130 for (i = 0; i < snap_count; i++) 5131 snapc->snaps[i] = ceph_decode_64(&p); 5132 5133 ceph_put_snap_context(rbd_dev->header.snapc); 5134 rbd_dev->header.snapc = snapc; 5135 5136 dout(" snap context seq = %llu, snap_count = %u\n", 5137 (unsigned long long)seq, (unsigned int)snap_count); 5138 out: 5139 kfree(reply_buf); 5140 5141 return ret; 5142 } 5143 5144 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, 5145 u64 snap_id) 5146 { 5147 size_t size; 5148 void *reply_buf; 5149 __le64 snapid; 5150 int ret; 5151 void *p; 5152 void *end; 5153 char *snap_name; 5154 5155 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN; 5156 reply_buf = kmalloc(size, GFP_KERNEL); 5157 if (!reply_buf) 5158 return ERR_PTR(-ENOMEM); 5159 5160 snapid = cpu_to_le64(snap_id); 5161 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 5162 &rbd_dev->header_oloc, "get_snapshot_name", 5163 &snapid, sizeof(snapid), reply_buf, size); 5164 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 5165 if (ret < 0) { 5166 snap_name = ERR_PTR(ret); 5167 goto out; 5168 } 5169 5170 p = reply_buf; 5171 end = reply_buf + ret; 5172 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL); 5173 if (IS_ERR(snap_name)) 5174 goto out; 5175 5176 dout(" snap_id 0x%016llx snap_name = %s\n", 5177 (unsigned long long)snap_id, snap_name); 5178 out: 5179 kfree(reply_buf); 5180 5181 return snap_name; 5182 } 5183 5184 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev) 5185 { 5186 bool first_time = rbd_dev->header.object_prefix == NULL; 5187 int ret; 5188 5189 ret = rbd_dev_v2_image_size(rbd_dev); 5190 if (ret) 5191 return ret; 5192 5193 if (first_time) { 5194 ret = rbd_dev_v2_header_onetime(rbd_dev); 5195 if (ret) 5196 return ret; 5197 } 5198 5199 ret = rbd_dev_v2_snap_context(rbd_dev); 5200 if (ret && first_time) { 5201 kfree(rbd_dev->header.object_prefix); 5202 rbd_dev->header.object_prefix = NULL; 5203 } 5204 5205 return ret; 5206 } 5207 5208 static int rbd_dev_header_info(struct rbd_device *rbd_dev) 5209 { 5210 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 5211 5212 if (rbd_dev->image_format == 1) 5213 return rbd_dev_v1_header_info(rbd_dev); 5214 5215 return rbd_dev_v2_header_info(rbd_dev); 5216 } 5217 5218 /* 5219 * Skips over white space at *buf, and updates *buf to point to the 5220 * first found non-space character (if any). Returns the length of 5221 * the token (string of non-white space characters) found. Note 5222 * that *buf must be terminated with '\0'. 5223 */ 5224 static inline size_t next_token(const char **buf) 5225 { 5226 /* 5227 * These are the characters that produce nonzero for 5228 * isspace() in the "C" and "POSIX" locales. 5229 */ 5230 const char *spaces = " \f\n\r\t\v"; 5231 5232 *buf += strspn(*buf, spaces); /* Find start of token */ 5233 5234 return strcspn(*buf, spaces); /* Return token length */ 5235 } 5236 5237 /* 5238 * Finds the next token in *buf, dynamically allocates a buffer big 5239 * enough to hold a copy of it, and copies the token into the new 5240 * buffer. The copy is guaranteed to be terminated with '\0'. Note 5241 * that a duplicate buffer is created even for a zero-length token. 5242 * 5243 * Returns a pointer to the newly-allocated duplicate, or a null 5244 * pointer if memory for the duplicate was not available. If 5245 * the lenp argument is a non-null pointer, the length of the token 5246 * (not including the '\0') is returned in *lenp. 5247 * 5248 * If successful, the *buf pointer will be updated to point beyond 5249 * the end of the found token. 5250 * 5251 * Note: uses GFP_KERNEL for allocation. 5252 */ 5253 static inline char *dup_token(const char **buf, size_t *lenp) 5254 { 5255 char *dup; 5256 size_t len; 5257 5258 len = next_token(buf); 5259 dup = kmemdup(*buf, len + 1, GFP_KERNEL); 5260 if (!dup) 5261 return NULL; 5262 *(dup + len) = '\0'; 5263 *buf += len; 5264 5265 if (lenp) 5266 *lenp = len; 5267 5268 return dup; 5269 } 5270 5271 /* 5272 * Parse the options provided for an "rbd add" (i.e., rbd image 5273 * mapping) request. These arrive via a write to /sys/bus/rbd/add, 5274 * and the data written is passed here via a NUL-terminated buffer. 5275 * Returns 0 if successful or an error code otherwise. 5276 * 5277 * The information extracted from these options is recorded in 5278 * the other parameters which return dynamically-allocated 5279 * structures: 5280 * ceph_opts 5281 * The address of a pointer that will refer to a ceph options 5282 * structure. Caller must release the returned pointer using 5283 * ceph_destroy_options() when it is no longer needed. 5284 * rbd_opts 5285 * Address of an rbd options pointer. Fully initialized by 5286 * this function; caller must release with kfree(). 5287 * spec 5288 * Address of an rbd image specification pointer. Fully 5289 * initialized by this function based on parsed options. 5290 * Caller must release with rbd_spec_put(). 5291 * 5292 * The options passed take this form: 5293 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>] 5294 * where: 5295 * <mon_addrs> 5296 * A comma-separated list of one or more monitor addresses. 5297 * A monitor address is an ip address, optionally followed 5298 * by a port number (separated by a colon). 5299 * I.e.: ip1[:port1][,ip2[:port2]...] 5300 * <options> 5301 * A comma-separated list of ceph and/or rbd options. 5302 * <pool_name> 5303 * The name of the rados pool containing the rbd image. 5304 * <image_name> 5305 * The name of the image in that pool to map. 5306 * <snap_id> 5307 * An optional snapshot id. If provided, the mapping will 5308 * present data from the image at the time that snapshot was 5309 * created. The image head is used if no snapshot id is 5310 * provided. Snapshot mappings are always read-only. 5311 */ 5312 static int rbd_add_parse_args(const char *buf, 5313 struct ceph_options **ceph_opts, 5314 struct rbd_options **opts, 5315 struct rbd_spec **rbd_spec) 5316 { 5317 size_t len; 5318 char *options; 5319 const char *mon_addrs; 5320 char *snap_name; 5321 size_t mon_addrs_size; 5322 struct parse_rbd_opts_ctx pctx = { 0 }; 5323 struct ceph_options *copts; 5324 int ret; 5325 5326 /* The first four tokens are required */ 5327 5328 len = next_token(&buf); 5329 if (!len) { 5330 rbd_warn(NULL, "no monitor address(es) provided"); 5331 return -EINVAL; 5332 } 5333 mon_addrs = buf; 5334 mon_addrs_size = len + 1; 5335 buf += len; 5336 5337 ret = -EINVAL; 5338 options = dup_token(&buf, NULL); 5339 if (!options) 5340 return -ENOMEM; 5341 if (!*options) { 5342 rbd_warn(NULL, "no options provided"); 5343 goto out_err; 5344 } 5345 5346 pctx.spec = rbd_spec_alloc(); 5347 if (!pctx.spec) 5348 goto out_mem; 5349 5350 pctx.spec->pool_name = dup_token(&buf, NULL); 5351 if (!pctx.spec->pool_name) 5352 goto out_mem; 5353 if (!*pctx.spec->pool_name) { 5354 rbd_warn(NULL, "no pool name provided"); 5355 goto out_err; 5356 } 5357 5358 pctx.spec->image_name = dup_token(&buf, NULL); 5359 if (!pctx.spec->image_name) 5360 goto out_mem; 5361 if (!*pctx.spec->image_name) { 5362 rbd_warn(NULL, "no image name provided"); 5363 goto out_err; 5364 } 5365 5366 /* 5367 * Snapshot name is optional; default is to use "-" 5368 * (indicating the head/no snapshot). 5369 */ 5370 len = next_token(&buf); 5371 if (!len) { 5372 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */ 5373 len = sizeof (RBD_SNAP_HEAD_NAME) - 1; 5374 } else if (len > RBD_MAX_SNAP_NAME_LEN) { 5375 ret = -ENAMETOOLONG; 5376 goto out_err; 5377 } 5378 snap_name = kmemdup(buf, len + 1, GFP_KERNEL); 5379 if (!snap_name) 5380 goto out_mem; 5381 *(snap_name + len) = '\0'; 5382 pctx.spec->snap_name = snap_name; 5383 5384 /* Initialize all rbd options to the defaults */ 5385 5386 pctx.opts = kzalloc(sizeof(*pctx.opts), GFP_KERNEL); 5387 if (!pctx.opts) 5388 goto out_mem; 5389 5390 pctx.opts->read_only = RBD_READ_ONLY_DEFAULT; 5391 pctx.opts->queue_depth = RBD_QUEUE_DEPTH_DEFAULT; 5392 pctx.opts->lock_timeout = RBD_LOCK_TIMEOUT_DEFAULT; 5393 pctx.opts->lock_on_read = RBD_LOCK_ON_READ_DEFAULT; 5394 pctx.opts->exclusive = RBD_EXCLUSIVE_DEFAULT; 5395 pctx.opts->trim = RBD_TRIM_DEFAULT; 5396 5397 copts = ceph_parse_options(options, mon_addrs, 5398 mon_addrs + mon_addrs_size - 1, 5399 parse_rbd_opts_token, &pctx); 5400 if (IS_ERR(copts)) { 5401 ret = PTR_ERR(copts); 5402 goto out_err; 5403 } 5404 kfree(options); 5405 5406 *ceph_opts = copts; 5407 *opts = pctx.opts; 5408 *rbd_spec = pctx.spec; 5409 5410 return 0; 5411 out_mem: 5412 ret = -ENOMEM; 5413 out_err: 5414 kfree(pctx.opts); 5415 rbd_spec_put(pctx.spec); 5416 kfree(options); 5417 5418 return ret; 5419 } 5420 5421 static void rbd_dev_image_unlock(struct rbd_device *rbd_dev) 5422 { 5423 down_write(&rbd_dev->lock_rwsem); 5424 if (__rbd_is_lock_owner(rbd_dev)) 5425 rbd_unlock(rbd_dev); 5426 up_write(&rbd_dev->lock_rwsem); 5427 } 5428 5429 static int rbd_add_acquire_lock(struct rbd_device *rbd_dev) 5430 { 5431 int ret; 5432 5433 if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) { 5434 rbd_warn(rbd_dev, "exclusive-lock feature is not enabled"); 5435 return -EINVAL; 5436 } 5437 5438 /* FIXME: "rbd map --exclusive" should be in interruptible */ 5439 down_read(&rbd_dev->lock_rwsem); 5440 ret = rbd_wait_state_locked(rbd_dev, true); 5441 up_read(&rbd_dev->lock_rwsem); 5442 if (ret) { 5443 rbd_warn(rbd_dev, "failed to acquire exclusive lock"); 5444 return -EROFS; 5445 } 5446 5447 return 0; 5448 } 5449 5450 /* 5451 * An rbd format 2 image has a unique identifier, distinct from the 5452 * name given to it by the user. Internally, that identifier is 5453 * what's used to specify the names of objects related to the image. 5454 * 5455 * A special "rbd id" object is used to map an rbd image name to its 5456 * id. If that object doesn't exist, then there is no v2 rbd image 5457 * with the supplied name. 5458 * 5459 * This function will record the given rbd_dev's image_id field if 5460 * it can be determined, and in that case will return 0. If any 5461 * errors occur a negative errno will be returned and the rbd_dev's 5462 * image_id field will be unchanged (and should be NULL). 5463 */ 5464 static int rbd_dev_image_id(struct rbd_device *rbd_dev) 5465 { 5466 int ret; 5467 size_t size; 5468 CEPH_DEFINE_OID_ONSTACK(oid); 5469 void *response; 5470 char *image_id; 5471 5472 /* 5473 * When probing a parent image, the image id is already 5474 * known (and the image name likely is not). There's no 5475 * need to fetch the image id again in this case. We 5476 * do still need to set the image format though. 5477 */ 5478 if (rbd_dev->spec->image_id) { 5479 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1; 5480 5481 return 0; 5482 } 5483 5484 /* 5485 * First, see if the format 2 image id file exists, and if 5486 * so, get the image's persistent id from it. 5487 */ 5488 ret = ceph_oid_aprintf(&oid, GFP_KERNEL, "%s%s", RBD_ID_PREFIX, 5489 rbd_dev->spec->image_name); 5490 if (ret) 5491 return ret; 5492 5493 dout("rbd id object name is %s\n", oid.name); 5494 5495 /* Response will be an encoded string, which includes a length */ 5496 5497 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX; 5498 response = kzalloc(size, GFP_NOIO); 5499 if (!response) { 5500 ret = -ENOMEM; 5501 goto out; 5502 } 5503 5504 /* If it doesn't exist we'll assume it's a format 1 image */ 5505 5506 ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc, 5507 "get_id", NULL, 0, 5508 response, RBD_IMAGE_ID_LEN_MAX); 5509 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 5510 if (ret == -ENOENT) { 5511 image_id = kstrdup("", GFP_KERNEL); 5512 ret = image_id ? 0 : -ENOMEM; 5513 if (!ret) 5514 rbd_dev->image_format = 1; 5515 } else if (ret >= 0) { 5516 void *p = response; 5517 5518 image_id = ceph_extract_encoded_string(&p, p + ret, 5519 NULL, GFP_NOIO); 5520 ret = PTR_ERR_OR_ZERO(image_id); 5521 if (!ret) 5522 rbd_dev->image_format = 2; 5523 } 5524 5525 if (!ret) { 5526 rbd_dev->spec->image_id = image_id; 5527 dout("image_id is %s\n", image_id); 5528 } 5529 out: 5530 kfree(response); 5531 ceph_oid_destroy(&oid); 5532 return ret; 5533 } 5534 5535 /* 5536 * Undo whatever state changes are made by v1 or v2 header info 5537 * call. 5538 */ 5539 static void rbd_dev_unprobe(struct rbd_device *rbd_dev) 5540 { 5541 struct rbd_image_header *header; 5542 5543 rbd_dev_parent_put(rbd_dev); 5544 5545 /* Free dynamic fields from the header, then zero it out */ 5546 5547 header = &rbd_dev->header; 5548 ceph_put_snap_context(header->snapc); 5549 kfree(header->snap_sizes); 5550 kfree(header->snap_names); 5551 kfree(header->object_prefix); 5552 memset(header, 0, sizeof (*header)); 5553 } 5554 5555 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev) 5556 { 5557 int ret; 5558 5559 ret = rbd_dev_v2_object_prefix(rbd_dev); 5560 if (ret) 5561 goto out_err; 5562 5563 /* 5564 * Get the and check features for the image. Currently the 5565 * features are assumed to never change. 5566 */ 5567 ret = rbd_dev_v2_features(rbd_dev); 5568 if (ret) 5569 goto out_err; 5570 5571 /* If the image supports fancy striping, get its parameters */ 5572 5573 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) { 5574 ret = rbd_dev_v2_striping_info(rbd_dev); 5575 if (ret < 0) 5576 goto out_err; 5577 } 5578 5579 if (rbd_dev->header.features & RBD_FEATURE_DATA_POOL) { 5580 ret = rbd_dev_v2_data_pool(rbd_dev); 5581 if (ret) 5582 goto out_err; 5583 } 5584 5585 rbd_init_layout(rbd_dev); 5586 return 0; 5587 5588 out_err: 5589 rbd_dev->header.features = 0; 5590 kfree(rbd_dev->header.object_prefix); 5591 rbd_dev->header.object_prefix = NULL; 5592 return ret; 5593 } 5594 5595 /* 5596 * @depth is rbd_dev_image_probe() -> rbd_dev_probe_parent() -> 5597 * rbd_dev_image_probe() recursion depth, which means it's also the 5598 * length of the already discovered part of the parent chain. 5599 */ 5600 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev, int depth) 5601 { 5602 struct rbd_device *parent = NULL; 5603 int ret; 5604 5605 if (!rbd_dev->parent_spec) 5606 return 0; 5607 5608 if (++depth > RBD_MAX_PARENT_CHAIN_LEN) { 5609 pr_info("parent chain is too long (%d)\n", depth); 5610 ret = -EINVAL; 5611 goto out_err; 5612 } 5613 5614 parent = __rbd_dev_create(rbd_dev->rbd_client, rbd_dev->parent_spec); 5615 if (!parent) { 5616 ret = -ENOMEM; 5617 goto out_err; 5618 } 5619 5620 /* 5621 * Images related by parent/child relationships always share 5622 * rbd_client and spec/parent_spec, so bump their refcounts. 5623 */ 5624 __rbd_get_client(rbd_dev->rbd_client); 5625 rbd_spec_get(rbd_dev->parent_spec); 5626 5627 ret = rbd_dev_image_probe(parent, depth); 5628 if (ret < 0) 5629 goto out_err; 5630 5631 rbd_dev->parent = parent; 5632 atomic_set(&rbd_dev->parent_ref, 1); 5633 return 0; 5634 5635 out_err: 5636 rbd_dev_unparent(rbd_dev); 5637 rbd_dev_destroy(parent); 5638 return ret; 5639 } 5640 5641 static void rbd_dev_device_release(struct rbd_device *rbd_dev) 5642 { 5643 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); 5644 rbd_dev_mapping_clear(rbd_dev); 5645 rbd_free_disk(rbd_dev); 5646 if (!single_major) 5647 unregister_blkdev(rbd_dev->major, rbd_dev->name); 5648 } 5649 5650 /* 5651 * rbd_dev->header_rwsem must be locked for write and will be unlocked 5652 * upon return. 5653 */ 5654 static int rbd_dev_device_setup(struct rbd_device *rbd_dev) 5655 { 5656 int ret; 5657 5658 /* Record our major and minor device numbers. */ 5659 5660 if (!single_major) { 5661 ret = register_blkdev(0, rbd_dev->name); 5662 if (ret < 0) 5663 goto err_out_unlock; 5664 5665 rbd_dev->major = ret; 5666 rbd_dev->minor = 0; 5667 } else { 5668 rbd_dev->major = rbd_major; 5669 rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id); 5670 } 5671 5672 /* Set up the blkdev mapping. */ 5673 5674 ret = rbd_init_disk(rbd_dev); 5675 if (ret) 5676 goto err_out_blkdev; 5677 5678 ret = rbd_dev_mapping_set(rbd_dev); 5679 if (ret) 5680 goto err_out_disk; 5681 5682 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE); 5683 set_disk_ro(rbd_dev->disk, rbd_dev->opts->read_only); 5684 5685 ret = dev_set_name(&rbd_dev->dev, "%d", rbd_dev->dev_id); 5686 if (ret) 5687 goto err_out_mapping; 5688 5689 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); 5690 up_write(&rbd_dev->header_rwsem); 5691 return 0; 5692 5693 err_out_mapping: 5694 rbd_dev_mapping_clear(rbd_dev); 5695 err_out_disk: 5696 rbd_free_disk(rbd_dev); 5697 err_out_blkdev: 5698 if (!single_major) 5699 unregister_blkdev(rbd_dev->major, rbd_dev->name); 5700 err_out_unlock: 5701 up_write(&rbd_dev->header_rwsem); 5702 return ret; 5703 } 5704 5705 static int rbd_dev_header_name(struct rbd_device *rbd_dev) 5706 { 5707 struct rbd_spec *spec = rbd_dev->spec; 5708 int ret; 5709 5710 /* Record the header object name for this rbd image. */ 5711 5712 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 5713 if (rbd_dev->image_format == 1) 5714 ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s", 5715 spec->image_name, RBD_SUFFIX); 5716 else 5717 ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s", 5718 RBD_HEADER_PREFIX, spec->image_id); 5719 5720 return ret; 5721 } 5722 5723 static void rbd_dev_image_release(struct rbd_device *rbd_dev) 5724 { 5725 rbd_dev_unprobe(rbd_dev); 5726 if (rbd_dev->opts) 5727 rbd_unregister_watch(rbd_dev); 5728 rbd_dev->image_format = 0; 5729 kfree(rbd_dev->spec->image_id); 5730 rbd_dev->spec->image_id = NULL; 5731 } 5732 5733 /* 5734 * Probe for the existence of the header object for the given rbd 5735 * device. If this image is the one being mapped (i.e., not a 5736 * parent), initiate a watch on its header object before using that 5737 * object to get detailed information about the rbd image. 5738 */ 5739 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth) 5740 { 5741 int ret; 5742 5743 /* 5744 * Get the id from the image id object. Unless there's an 5745 * error, rbd_dev->spec->image_id will be filled in with 5746 * a dynamically-allocated string, and rbd_dev->image_format 5747 * will be set to either 1 or 2. 5748 */ 5749 ret = rbd_dev_image_id(rbd_dev); 5750 if (ret) 5751 return ret; 5752 5753 ret = rbd_dev_header_name(rbd_dev); 5754 if (ret) 5755 goto err_out_format; 5756 5757 if (!depth) { 5758 ret = rbd_register_watch(rbd_dev); 5759 if (ret) { 5760 if (ret == -ENOENT) 5761 pr_info("image %s/%s%s%s does not exist\n", 5762 rbd_dev->spec->pool_name, 5763 rbd_dev->spec->pool_ns ?: "", 5764 rbd_dev->spec->pool_ns ? "/" : "", 5765 rbd_dev->spec->image_name); 5766 goto err_out_format; 5767 } 5768 } 5769 5770 ret = rbd_dev_header_info(rbd_dev); 5771 if (ret) 5772 goto err_out_watch; 5773 5774 /* 5775 * If this image is the one being mapped, we have pool name and 5776 * id, image name and id, and snap name - need to fill snap id. 5777 * Otherwise this is a parent image, identified by pool, image 5778 * and snap ids - need to fill in names for those ids. 5779 */ 5780 if (!depth) 5781 ret = rbd_spec_fill_snap_id(rbd_dev); 5782 else 5783 ret = rbd_spec_fill_names(rbd_dev); 5784 if (ret) { 5785 if (ret == -ENOENT) 5786 pr_info("snap %s/%s%s%s@%s does not exist\n", 5787 rbd_dev->spec->pool_name, 5788 rbd_dev->spec->pool_ns ?: "", 5789 rbd_dev->spec->pool_ns ? "/" : "", 5790 rbd_dev->spec->image_name, 5791 rbd_dev->spec->snap_name); 5792 goto err_out_probe; 5793 } 5794 5795 if (rbd_dev->header.features & RBD_FEATURE_LAYERING) { 5796 ret = rbd_dev_v2_parent_info(rbd_dev); 5797 if (ret) 5798 goto err_out_probe; 5799 5800 /* 5801 * Need to warn users if this image is the one being 5802 * mapped and has a parent. 5803 */ 5804 if (!depth && rbd_dev->parent_spec) 5805 rbd_warn(rbd_dev, 5806 "WARNING: kernel layering is EXPERIMENTAL!"); 5807 } 5808 5809 ret = rbd_dev_probe_parent(rbd_dev, depth); 5810 if (ret) 5811 goto err_out_probe; 5812 5813 dout("discovered format %u image, header name is %s\n", 5814 rbd_dev->image_format, rbd_dev->header_oid.name); 5815 return 0; 5816 5817 err_out_probe: 5818 rbd_dev_unprobe(rbd_dev); 5819 err_out_watch: 5820 if (!depth) 5821 rbd_unregister_watch(rbd_dev); 5822 err_out_format: 5823 rbd_dev->image_format = 0; 5824 kfree(rbd_dev->spec->image_id); 5825 rbd_dev->spec->image_id = NULL; 5826 return ret; 5827 } 5828 5829 static ssize_t do_rbd_add(struct bus_type *bus, 5830 const char *buf, 5831 size_t count) 5832 { 5833 struct rbd_device *rbd_dev = NULL; 5834 struct ceph_options *ceph_opts = NULL; 5835 struct rbd_options *rbd_opts = NULL; 5836 struct rbd_spec *spec = NULL; 5837 struct rbd_client *rbdc; 5838 int rc; 5839 5840 if (!try_module_get(THIS_MODULE)) 5841 return -ENODEV; 5842 5843 /* parse add command */ 5844 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec); 5845 if (rc < 0) 5846 goto out; 5847 5848 rbdc = rbd_get_client(ceph_opts); 5849 if (IS_ERR(rbdc)) { 5850 rc = PTR_ERR(rbdc); 5851 goto err_out_args; 5852 } 5853 5854 /* pick the pool */ 5855 rc = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, spec->pool_name); 5856 if (rc < 0) { 5857 if (rc == -ENOENT) 5858 pr_info("pool %s does not exist\n", spec->pool_name); 5859 goto err_out_client; 5860 } 5861 spec->pool_id = (u64)rc; 5862 5863 rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts); 5864 if (!rbd_dev) { 5865 rc = -ENOMEM; 5866 goto err_out_client; 5867 } 5868 rbdc = NULL; /* rbd_dev now owns this */ 5869 spec = NULL; /* rbd_dev now owns this */ 5870 rbd_opts = NULL; /* rbd_dev now owns this */ 5871 5872 rbd_dev->config_info = kstrdup(buf, GFP_KERNEL); 5873 if (!rbd_dev->config_info) { 5874 rc = -ENOMEM; 5875 goto err_out_rbd_dev; 5876 } 5877 5878 down_write(&rbd_dev->header_rwsem); 5879 rc = rbd_dev_image_probe(rbd_dev, 0); 5880 if (rc < 0) { 5881 up_write(&rbd_dev->header_rwsem); 5882 goto err_out_rbd_dev; 5883 } 5884 5885 /* If we are mapping a snapshot it must be marked read-only */ 5886 if (rbd_dev->spec->snap_id != CEPH_NOSNAP) 5887 rbd_dev->opts->read_only = true; 5888 5889 rc = rbd_dev_device_setup(rbd_dev); 5890 if (rc) 5891 goto err_out_image_probe; 5892 5893 if (rbd_dev->opts->exclusive) { 5894 rc = rbd_add_acquire_lock(rbd_dev); 5895 if (rc) 5896 goto err_out_device_setup; 5897 } 5898 5899 /* Everything's ready. Announce the disk to the world. */ 5900 5901 rc = device_add(&rbd_dev->dev); 5902 if (rc) 5903 goto err_out_image_lock; 5904 5905 add_disk(rbd_dev->disk); 5906 /* see rbd_init_disk() */ 5907 blk_put_queue(rbd_dev->disk->queue); 5908 5909 spin_lock(&rbd_dev_list_lock); 5910 list_add_tail(&rbd_dev->node, &rbd_dev_list); 5911 spin_unlock(&rbd_dev_list_lock); 5912 5913 pr_info("%s: capacity %llu features 0x%llx\n", rbd_dev->disk->disk_name, 5914 (unsigned long long)get_capacity(rbd_dev->disk) << SECTOR_SHIFT, 5915 rbd_dev->header.features); 5916 rc = count; 5917 out: 5918 module_put(THIS_MODULE); 5919 return rc; 5920 5921 err_out_image_lock: 5922 rbd_dev_image_unlock(rbd_dev); 5923 err_out_device_setup: 5924 rbd_dev_device_release(rbd_dev); 5925 err_out_image_probe: 5926 rbd_dev_image_release(rbd_dev); 5927 err_out_rbd_dev: 5928 rbd_dev_destroy(rbd_dev); 5929 err_out_client: 5930 rbd_put_client(rbdc); 5931 err_out_args: 5932 rbd_spec_put(spec); 5933 kfree(rbd_opts); 5934 goto out; 5935 } 5936 5937 static ssize_t rbd_add(struct bus_type *bus, 5938 const char *buf, 5939 size_t count) 5940 { 5941 if (single_major) 5942 return -EINVAL; 5943 5944 return do_rbd_add(bus, buf, count); 5945 } 5946 5947 static ssize_t rbd_add_single_major(struct bus_type *bus, 5948 const char *buf, 5949 size_t count) 5950 { 5951 return do_rbd_add(bus, buf, count); 5952 } 5953 5954 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev) 5955 { 5956 while (rbd_dev->parent) { 5957 struct rbd_device *first = rbd_dev; 5958 struct rbd_device *second = first->parent; 5959 struct rbd_device *third; 5960 5961 /* 5962 * Follow to the parent with no grandparent and 5963 * remove it. 5964 */ 5965 while (second && (third = second->parent)) { 5966 first = second; 5967 second = third; 5968 } 5969 rbd_assert(second); 5970 rbd_dev_image_release(second); 5971 rbd_dev_destroy(second); 5972 first->parent = NULL; 5973 first->parent_overlap = 0; 5974 5975 rbd_assert(first->parent_spec); 5976 rbd_spec_put(first->parent_spec); 5977 first->parent_spec = NULL; 5978 } 5979 } 5980 5981 static ssize_t do_rbd_remove(struct bus_type *bus, 5982 const char *buf, 5983 size_t count) 5984 { 5985 struct rbd_device *rbd_dev = NULL; 5986 struct list_head *tmp; 5987 int dev_id; 5988 char opt_buf[6]; 5989 bool force = false; 5990 int ret; 5991 5992 dev_id = -1; 5993 opt_buf[0] = '\0'; 5994 sscanf(buf, "%d %5s", &dev_id, opt_buf); 5995 if (dev_id < 0) { 5996 pr_err("dev_id out of range\n"); 5997 return -EINVAL; 5998 } 5999 if (opt_buf[0] != '\0') { 6000 if (!strcmp(opt_buf, "force")) { 6001 force = true; 6002 } else { 6003 pr_err("bad remove option at '%s'\n", opt_buf); 6004 return -EINVAL; 6005 } 6006 } 6007 6008 ret = -ENOENT; 6009 spin_lock(&rbd_dev_list_lock); 6010 list_for_each(tmp, &rbd_dev_list) { 6011 rbd_dev = list_entry(tmp, struct rbd_device, node); 6012 if (rbd_dev->dev_id == dev_id) { 6013 ret = 0; 6014 break; 6015 } 6016 } 6017 if (!ret) { 6018 spin_lock_irq(&rbd_dev->lock); 6019 if (rbd_dev->open_count && !force) 6020 ret = -EBUSY; 6021 else if (test_and_set_bit(RBD_DEV_FLAG_REMOVING, 6022 &rbd_dev->flags)) 6023 ret = -EINPROGRESS; 6024 spin_unlock_irq(&rbd_dev->lock); 6025 } 6026 spin_unlock(&rbd_dev_list_lock); 6027 if (ret) 6028 return ret; 6029 6030 if (force) { 6031 /* 6032 * Prevent new IO from being queued and wait for existing 6033 * IO to complete/fail. 6034 */ 6035 blk_mq_freeze_queue(rbd_dev->disk->queue); 6036 blk_set_queue_dying(rbd_dev->disk->queue); 6037 } 6038 6039 del_gendisk(rbd_dev->disk); 6040 spin_lock(&rbd_dev_list_lock); 6041 list_del_init(&rbd_dev->node); 6042 spin_unlock(&rbd_dev_list_lock); 6043 device_del(&rbd_dev->dev); 6044 6045 rbd_dev_image_unlock(rbd_dev); 6046 rbd_dev_device_release(rbd_dev); 6047 rbd_dev_image_release(rbd_dev); 6048 rbd_dev_destroy(rbd_dev); 6049 return count; 6050 } 6051 6052 static ssize_t rbd_remove(struct bus_type *bus, 6053 const char *buf, 6054 size_t count) 6055 { 6056 if (single_major) 6057 return -EINVAL; 6058 6059 return do_rbd_remove(bus, buf, count); 6060 } 6061 6062 static ssize_t rbd_remove_single_major(struct bus_type *bus, 6063 const char *buf, 6064 size_t count) 6065 { 6066 return do_rbd_remove(bus, buf, count); 6067 } 6068 6069 /* 6070 * create control files in sysfs 6071 * /sys/bus/rbd/... 6072 */ 6073 static int __init rbd_sysfs_init(void) 6074 { 6075 int ret; 6076 6077 ret = device_register(&rbd_root_dev); 6078 if (ret < 0) 6079 return ret; 6080 6081 ret = bus_register(&rbd_bus_type); 6082 if (ret < 0) 6083 device_unregister(&rbd_root_dev); 6084 6085 return ret; 6086 } 6087 6088 static void __exit rbd_sysfs_cleanup(void) 6089 { 6090 bus_unregister(&rbd_bus_type); 6091 device_unregister(&rbd_root_dev); 6092 } 6093 6094 static int __init rbd_slab_init(void) 6095 { 6096 rbd_assert(!rbd_img_request_cache); 6097 rbd_img_request_cache = KMEM_CACHE(rbd_img_request, 0); 6098 if (!rbd_img_request_cache) 6099 return -ENOMEM; 6100 6101 rbd_assert(!rbd_obj_request_cache); 6102 rbd_obj_request_cache = KMEM_CACHE(rbd_obj_request, 0); 6103 if (!rbd_obj_request_cache) 6104 goto out_err; 6105 6106 return 0; 6107 6108 out_err: 6109 kmem_cache_destroy(rbd_img_request_cache); 6110 rbd_img_request_cache = NULL; 6111 return -ENOMEM; 6112 } 6113 6114 static void rbd_slab_exit(void) 6115 { 6116 rbd_assert(rbd_obj_request_cache); 6117 kmem_cache_destroy(rbd_obj_request_cache); 6118 rbd_obj_request_cache = NULL; 6119 6120 rbd_assert(rbd_img_request_cache); 6121 kmem_cache_destroy(rbd_img_request_cache); 6122 rbd_img_request_cache = NULL; 6123 } 6124 6125 static int __init rbd_init(void) 6126 { 6127 int rc; 6128 6129 if (!libceph_compatible(NULL)) { 6130 rbd_warn(NULL, "libceph incompatibility (quitting)"); 6131 return -EINVAL; 6132 } 6133 6134 rc = rbd_slab_init(); 6135 if (rc) 6136 return rc; 6137 6138 /* 6139 * The number of active work items is limited by the number of 6140 * rbd devices * queue depth, so leave @max_active at default. 6141 */ 6142 rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0); 6143 if (!rbd_wq) { 6144 rc = -ENOMEM; 6145 goto err_out_slab; 6146 } 6147 6148 if (single_major) { 6149 rbd_major = register_blkdev(0, RBD_DRV_NAME); 6150 if (rbd_major < 0) { 6151 rc = rbd_major; 6152 goto err_out_wq; 6153 } 6154 } 6155 6156 rc = rbd_sysfs_init(); 6157 if (rc) 6158 goto err_out_blkdev; 6159 6160 if (single_major) 6161 pr_info("loaded (major %d)\n", rbd_major); 6162 else 6163 pr_info("loaded\n"); 6164 6165 return 0; 6166 6167 err_out_blkdev: 6168 if (single_major) 6169 unregister_blkdev(rbd_major, RBD_DRV_NAME); 6170 err_out_wq: 6171 destroy_workqueue(rbd_wq); 6172 err_out_slab: 6173 rbd_slab_exit(); 6174 return rc; 6175 } 6176 6177 static void __exit rbd_exit(void) 6178 { 6179 ida_destroy(&rbd_dev_id_ida); 6180 rbd_sysfs_cleanup(); 6181 if (single_major) 6182 unregister_blkdev(rbd_major, RBD_DRV_NAME); 6183 destroy_workqueue(rbd_wq); 6184 rbd_slab_exit(); 6185 } 6186 6187 module_init(rbd_init); 6188 module_exit(rbd_exit); 6189 6190 MODULE_AUTHOR("Alex Elder <elder@inktank.com>"); 6191 MODULE_AUTHOR("Sage Weil <sage@newdream.net>"); 6192 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>"); 6193 /* following authorship retained from original osdblk.c */ 6194 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>"); 6195 6196 MODULE_DESCRIPTION("RADOS Block Device (RBD) driver"); 6197 MODULE_LICENSE("GPL"); 6198