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/fs_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_OBJECT_MAP (1ULL<<3) 119 #define RBD_FEATURE_FAST_DIFF (1ULL<<4) 120 #define RBD_FEATURE_DEEP_FLATTEN (1ULL<<5) 121 #define RBD_FEATURE_DATA_POOL (1ULL<<7) 122 #define RBD_FEATURE_OPERATIONS (1ULL<<8) 123 124 #define RBD_FEATURES_ALL (RBD_FEATURE_LAYERING | \ 125 RBD_FEATURE_STRIPINGV2 | \ 126 RBD_FEATURE_EXCLUSIVE_LOCK | \ 127 RBD_FEATURE_OBJECT_MAP | \ 128 RBD_FEATURE_FAST_DIFF | \ 129 RBD_FEATURE_DEEP_FLATTEN | \ 130 RBD_FEATURE_DATA_POOL | \ 131 RBD_FEATURE_OPERATIONS) 132 133 /* Features supported by this (client software) implementation. */ 134 135 #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL) 136 137 /* 138 * An RBD device name will be "rbd#", where the "rbd" comes from 139 * RBD_DRV_NAME above, and # is a unique integer identifier. 140 */ 141 #define DEV_NAME_LEN 32 142 143 /* 144 * block device image metadata (in-memory version) 145 */ 146 struct rbd_image_header { 147 /* These six fields never change for a given rbd image */ 148 char *object_prefix; 149 __u8 obj_order; 150 u64 stripe_unit; 151 u64 stripe_count; 152 s64 data_pool_id; 153 u64 features; /* Might be changeable someday? */ 154 155 /* The remaining fields need to be updated occasionally */ 156 u64 image_size; 157 struct ceph_snap_context *snapc; 158 char *snap_names; /* format 1 only */ 159 u64 *snap_sizes; /* format 1 only */ 160 }; 161 162 /* 163 * An rbd image specification. 164 * 165 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely 166 * identify an image. Each rbd_dev structure includes a pointer to 167 * an rbd_spec structure that encapsulates this identity. 168 * 169 * Each of the id's in an rbd_spec has an associated name. For a 170 * user-mapped image, the names are supplied and the id's associated 171 * with them are looked up. For a layered image, a parent image is 172 * defined by the tuple, and the names are looked up. 173 * 174 * An rbd_dev structure contains a parent_spec pointer which is 175 * non-null if the image it represents is a child in a layered 176 * image. This pointer will refer to the rbd_spec structure used 177 * by the parent rbd_dev for its own identity (i.e., the structure 178 * is shared between the parent and child). 179 * 180 * Since these structures are populated once, during the discovery 181 * phase of image construction, they are effectively immutable so 182 * we make no effort to synchronize access to them. 183 * 184 * Note that code herein does not assume the image name is known (it 185 * could be a null pointer). 186 */ 187 struct rbd_spec { 188 u64 pool_id; 189 const char *pool_name; 190 const char *pool_ns; /* NULL if default, never "" */ 191 192 const char *image_id; 193 const char *image_name; 194 195 u64 snap_id; 196 const char *snap_name; 197 198 struct kref kref; 199 }; 200 201 /* 202 * an instance of the client. multiple devices may share an rbd client. 203 */ 204 struct rbd_client { 205 struct ceph_client *client; 206 struct kref kref; 207 struct list_head node; 208 }; 209 210 struct pending_result { 211 int result; /* first nonzero result */ 212 int num_pending; 213 }; 214 215 struct rbd_img_request; 216 217 enum obj_request_type { 218 OBJ_REQUEST_NODATA = 1, 219 OBJ_REQUEST_BIO, /* pointer into provided bio (list) */ 220 OBJ_REQUEST_BVECS, /* pointer into provided bio_vec array */ 221 OBJ_REQUEST_OWN_BVECS, /* private bio_vec array, doesn't own pages */ 222 }; 223 224 enum obj_operation_type { 225 OBJ_OP_READ = 1, 226 OBJ_OP_WRITE, 227 OBJ_OP_DISCARD, 228 OBJ_OP_ZEROOUT, 229 }; 230 231 #define RBD_OBJ_FLAG_DELETION (1U << 0) 232 #define RBD_OBJ_FLAG_COPYUP_ENABLED (1U << 1) 233 #define RBD_OBJ_FLAG_COPYUP_ZEROS (1U << 2) 234 #define RBD_OBJ_FLAG_MAY_EXIST (1U << 3) 235 #define RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT (1U << 4) 236 237 enum rbd_obj_read_state { 238 RBD_OBJ_READ_START = 1, 239 RBD_OBJ_READ_OBJECT, 240 RBD_OBJ_READ_PARENT, 241 }; 242 243 /* 244 * Writes go through the following state machine to deal with 245 * layering: 246 * 247 * . . . . . RBD_OBJ_WRITE_GUARD. . . . . . . . . . . . . . 248 * . | . 249 * . v . 250 * . RBD_OBJ_WRITE_READ_FROM_PARENT. . . . 251 * . | . . 252 * . v v (deep-copyup . 253 * (image . RBD_OBJ_WRITE_COPYUP_EMPTY_SNAPC . not needed) . 254 * flattened) v | . . 255 * . v . . 256 * . . . .RBD_OBJ_WRITE_COPYUP_OPS. . . . . (copyup . 257 * | not needed) v 258 * v . 259 * done . . . . . . . . . . . . . . . . . . 260 * ^ 261 * | 262 * RBD_OBJ_WRITE_FLAT 263 * 264 * Writes start in RBD_OBJ_WRITE_GUARD or _FLAT, depending on whether 265 * assert_exists guard is needed or not (in some cases it's not needed 266 * even if there is a parent). 267 */ 268 enum rbd_obj_write_state { 269 RBD_OBJ_WRITE_START = 1, 270 RBD_OBJ_WRITE_PRE_OBJECT_MAP, 271 RBD_OBJ_WRITE_OBJECT, 272 __RBD_OBJ_WRITE_COPYUP, 273 RBD_OBJ_WRITE_COPYUP, 274 RBD_OBJ_WRITE_POST_OBJECT_MAP, 275 }; 276 277 enum rbd_obj_copyup_state { 278 RBD_OBJ_COPYUP_START = 1, 279 RBD_OBJ_COPYUP_READ_PARENT, 280 __RBD_OBJ_COPYUP_OBJECT_MAPS, 281 RBD_OBJ_COPYUP_OBJECT_MAPS, 282 __RBD_OBJ_COPYUP_WRITE_OBJECT, 283 RBD_OBJ_COPYUP_WRITE_OBJECT, 284 }; 285 286 struct rbd_obj_request { 287 struct ceph_object_extent ex; 288 unsigned int flags; /* RBD_OBJ_FLAG_* */ 289 union { 290 enum rbd_obj_read_state read_state; /* for reads */ 291 enum rbd_obj_write_state write_state; /* for writes */ 292 }; 293 294 struct rbd_img_request *img_request; 295 struct ceph_file_extent *img_extents; 296 u32 num_img_extents; 297 298 union { 299 struct ceph_bio_iter bio_pos; 300 struct { 301 struct ceph_bvec_iter bvec_pos; 302 u32 bvec_count; 303 u32 bvec_idx; 304 }; 305 }; 306 307 enum rbd_obj_copyup_state copyup_state; 308 struct bio_vec *copyup_bvecs; 309 u32 copyup_bvec_count; 310 311 struct list_head osd_reqs; /* w/ r_private_item */ 312 313 struct mutex state_mutex; 314 struct pending_result pending; 315 struct kref kref; 316 }; 317 318 enum img_req_flags { 319 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */ 320 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */ 321 }; 322 323 enum rbd_img_state { 324 RBD_IMG_START = 1, 325 RBD_IMG_EXCLUSIVE_LOCK, 326 __RBD_IMG_OBJECT_REQUESTS, 327 RBD_IMG_OBJECT_REQUESTS, 328 }; 329 330 struct rbd_img_request { 331 struct rbd_device *rbd_dev; 332 enum obj_operation_type op_type; 333 enum obj_request_type data_type; 334 unsigned long flags; 335 enum rbd_img_state state; 336 union { 337 u64 snap_id; /* for reads */ 338 struct ceph_snap_context *snapc; /* for writes */ 339 }; 340 struct rbd_obj_request *obj_request; /* obj req initiator */ 341 342 struct list_head lock_item; 343 struct list_head object_extents; /* obj_req.ex structs */ 344 345 struct mutex state_mutex; 346 struct pending_result pending; 347 struct work_struct work; 348 int work_result; 349 }; 350 351 #define for_each_obj_request(ireq, oreq) \ 352 list_for_each_entry(oreq, &(ireq)->object_extents, ex.oe_item) 353 #define for_each_obj_request_safe(ireq, oreq, n) \ 354 list_for_each_entry_safe(oreq, n, &(ireq)->object_extents, ex.oe_item) 355 356 enum rbd_watch_state { 357 RBD_WATCH_STATE_UNREGISTERED, 358 RBD_WATCH_STATE_REGISTERED, 359 RBD_WATCH_STATE_ERROR, 360 }; 361 362 enum rbd_lock_state { 363 RBD_LOCK_STATE_UNLOCKED, 364 RBD_LOCK_STATE_LOCKED, 365 RBD_LOCK_STATE_RELEASING, 366 }; 367 368 /* WatchNotify::ClientId */ 369 struct rbd_client_id { 370 u64 gid; 371 u64 handle; 372 }; 373 374 struct rbd_mapping { 375 u64 size; 376 }; 377 378 /* 379 * a single device 380 */ 381 struct rbd_device { 382 int dev_id; /* blkdev unique id */ 383 384 int major; /* blkdev assigned major */ 385 int minor; 386 struct gendisk *disk; /* blkdev's gendisk and rq */ 387 388 u32 image_format; /* Either 1 or 2 */ 389 struct rbd_client *rbd_client; 390 391 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */ 392 393 spinlock_t lock; /* queue, flags, open_count */ 394 395 struct rbd_image_header header; 396 unsigned long flags; /* possibly lock protected */ 397 struct rbd_spec *spec; 398 struct rbd_options *opts; 399 char *config_info; /* add{,_single_major} string */ 400 401 struct ceph_object_id header_oid; 402 struct ceph_object_locator header_oloc; 403 404 struct ceph_file_layout layout; /* used for all rbd requests */ 405 406 struct mutex watch_mutex; 407 enum rbd_watch_state watch_state; 408 struct ceph_osd_linger_request *watch_handle; 409 u64 watch_cookie; 410 struct delayed_work watch_dwork; 411 412 struct rw_semaphore lock_rwsem; 413 enum rbd_lock_state lock_state; 414 char lock_cookie[32]; 415 struct rbd_client_id owner_cid; 416 struct work_struct acquired_lock_work; 417 struct work_struct released_lock_work; 418 struct delayed_work lock_dwork; 419 struct work_struct unlock_work; 420 spinlock_t lock_lists_lock; 421 struct list_head acquiring_list; 422 struct list_head running_list; 423 struct completion acquire_wait; 424 int acquire_err; 425 struct completion releasing_wait; 426 427 spinlock_t object_map_lock; 428 u8 *object_map; 429 u64 object_map_size; /* in objects */ 430 u64 object_map_flags; 431 432 struct workqueue_struct *task_wq; 433 434 struct rbd_spec *parent_spec; 435 u64 parent_overlap; 436 atomic_t parent_ref; 437 struct rbd_device *parent; 438 439 /* Block layer tags. */ 440 struct blk_mq_tag_set tag_set; 441 442 /* protects updating the header */ 443 struct rw_semaphore header_rwsem; 444 445 struct rbd_mapping mapping; 446 447 struct list_head node; 448 449 /* sysfs related */ 450 struct device dev; 451 unsigned long open_count; /* protected by lock */ 452 }; 453 454 /* 455 * Flag bits for rbd_dev->flags: 456 * - REMOVING (which is coupled with rbd_dev->open_count) is protected 457 * by rbd_dev->lock 458 */ 459 enum rbd_dev_flags { 460 RBD_DEV_FLAG_EXISTS, /* rbd_dev_device_setup() ran */ 461 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */ 462 RBD_DEV_FLAG_READONLY, /* -o ro or snapshot */ 463 }; 464 465 static DEFINE_MUTEX(client_mutex); /* Serialize client creation */ 466 467 static LIST_HEAD(rbd_dev_list); /* devices */ 468 static DEFINE_SPINLOCK(rbd_dev_list_lock); 469 470 static LIST_HEAD(rbd_client_list); /* clients */ 471 static DEFINE_SPINLOCK(rbd_client_list_lock); 472 473 /* Slab caches for frequently-allocated structures */ 474 475 static struct kmem_cache *rbd_img_request_cache; 476 static struct kmem_cache *rbd_obj_request_cache; 477 478 static int rbd_major; 479 static DEFINE_IDA(rbd_dev_id_ida); 480 481 static struct workqueue_struct *rbd_wq; 482 483 static struct ceph_snap_context rbd_empty_snapc = { 484 .nref = REFCOUNT_INIT(1), 485 }; 486 487 /* 488 * single-major requires >= 0.75 version of userspace rbd utility. 489 */ 490 static bool single_major = true; 491 module_param(single_major, bool, 0444); 492 MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: true)"); 493 494 static ssize_t add_store(struct bus_type *bus, const char *buf, size_t count); 495 static ssize_t remove_store(struct bus_type *bus, const char *buf, 496 size_t count); 497 static ssize_t add_single_major_store(struct bus_type *bus, const char *buf, 498 size_t count); 499 static ssize_t remove_single_major_store(struct bus_type *bus, const char *buf, 500 size_t count); 501 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth); 502 503 static int rbd_dev_id_to_minor(int dev_id) 504 { 505 return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT; 506 } 507 508 static int minor_to_rbd_dev_id(int minor) 509 { 510 return minor >> RBD_SINGLE_MAJOR_PART_SHIFT; 511 } 512 513 static bool rbd_is_ro(struct rbd_device *rbd_dev) 514 { 515 return test_bit(RBD_DEV_FLAG_READONLY, &rbd_dev->flags); 516 } 517 518 static bool rbd_is_snap(struct rbd_device *rbd_dev) 519 { 520 return rbd_dev->spec->snap_id != CEPH_NOSNAP; 521 } 522 523 static bool __rbd_is_lock_owner(struct rbd_device *rbd_dev) 524 { 525 lockdep_assert_held(&rbd_dev->lock_rwsem); 526 527 return rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED || 528 rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING; 529 } 530 531 static bool rbd_is_lock_owner(struct rbd_device *rbd_dev) 532 { 533 bool is_lock_owner; 534 535 down_read(&rbd_dev->lock_rwsem); 536 is_lock_owner = __rbd_is_lock_owner(rbd_dev); 537 up_read(&rbd_dev->lock_rwsem); 538 return is_lock_owner; 539 } 540 541 static ssize_t supported_features_show(struct bus_type *bus, char *buf) 542 { 543 return sprintf(buf, "0x%llx\n", RBD_FEATURES_SUPPORTED); 544 } 545 546 static BUS_ATTR_WO(add); 547 static BUS_ATTR_WO(remove); 548 static BUS_ATTR_WO(add_single_major); 549 static BUS_ATTR_WO(remove_single_major); 550 static BUS_ATTR_RO(supported_features); 551 552 static struct attribute *rbd_bus_attrs[] = { 553 &bus_attr_add.attr, 554 &bus_attr_remove.attr, 555 &bus_attr_add_single_major.attr, 556 &bus_attr_remove_single_major.attr, 557 &bus_attr_supported_features.attr, 558 NULL, 559 }; 560 561 static umode_t rbd_bus_is_visible(struct kobject *kobj, 562 struct attribute *attr, int index) 563 { 564 if (!single_major && 565 (attr == &bus_attr_add_single_major.attr || 566 attr == &bus_attr_remove_single_major.attr)) 567 return 0; 568 569 return attr->mode; 570 } 571 572 static const struct attribute_group rbd_bus_group = { 573 .attrs = rbd_bus_attrs, 574 .is_visible = rbd_bus_is_visible, 575 }; 576 __ATTRIBUTE_GROUPS(rbd_bus); 577 578 static struct bus_type rbd_bus_type = { 579 .name = "rbd", 580 .bus_groups = rbd_bus_groups, 581 }; 582 583 static void rbd_root_dev_release(struct device *dev) 584 { 585 } 586 587 static struct device rbd_root_dev = { 588 .init_name = "rbd", 589 .release = rbd_root_dev_release, 590 }; 591 592 static __printf(2, 3) 593 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...) 594 { 595 struct va_format vaf; 596 va_list args; 597 598 va_start(args, fmt); 599 vaf.fmt = fmt; 600 vaf.va = &args; 601 602 if (!rbd_dev) 603 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf); 604 else if (rbd_dev->disk) 605 printk(KERN_WARNING "%s: %s: %pV\n", 606 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf); 607 else if (rbd_dev->spec && rbd_dev->spec->image_name) 608 printk(KERN_WARNING "%s: image %s: %pV\n", 609 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf); 610 else if (rbd_dev->spec && rbd_dev->spec->image_id) 611 printk(KERN_WARNING "%s: id %s: %pV\n", 612 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf); 613 else /* punt */ 614 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n", 615 RBD_DRV_NAME, rbd_dev, &vaf); 616 va_end(args); 617 } 618 619 #ifdef RBD_DEBUG 620 #define rbd_assert(expr) \ 621 if (unlikely(!(expr))) { \ 622 printk(KERN_ERR "\nAssertion failure in %s() " \ 623 "at line %d:\n\n" \ 624 "\trbd_assert(%s);\n\n", \ 625 __func__, __LINE__, #expr); \ 626 BUG(); \ 627 } 628 #else /* !RBD_DEBUG */ 629 # define rbd_assert(expr) ((void) 0) 630 #endif /* !RBD_DEBUG */ 631 632 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev); 633 634 static int rbd_dev_refresh(struct rbd_device *rbd_dev); 635 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev); 636 static int rbd_dev_header_info(struct rbd_device *rbd_dev); 637 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev); 638 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, 639 u64 snap_id); 640 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 641 u8 *order, u64 *snap_size); 642 static int rbd_dev_v2_get_flags(struct rbd_device *rbd_dev); 643 644 static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result); 645 static void rbd_img_handle_request(struct rbd_img_request *img_req, int result); 646 647 /* 648 * Return true if nothing else is pending. 649 */ 650 static bool pending_result_dec(struct pending_result *pending, int *result) 651 { 652 rbd_assert(pending->num_pending > 0); 653 654 if (*result && !pending->result) 655 pending->result = *result; 656 if (--pending->num_pending) 657 return false; 658 659 *result = pending->result; 660 return true; 661 } 662 663 static int rbd_open(struct block_device *bdev, fmode_t mode) 664 { 665 struct rbd_device *rbd_dev = bdev->bd_disk->private_data; 666 bool removing = false; 667 668 spin_lock_irq(&rbd_dev->lock); 669 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) 670 removing = true; 671 else 672 rbd_dev->open_count++; 673 spin_unlock_irq(&rbd_dev->lock); 674 if (removing) 675 return -ENOENT; 676 677 (void) get_device(&rbd_dev->dev); 678 679 return 0; 680 } 681 682 static void rbd_release(struct gendisk *disk, fmode_t mode) 683 { 684 struct rbd_device *rbd_dev = disk->private_data; 685 unsigned long open_count_before; 686 687 spin_lock_irq(&rbd_dev->lock); 688 open_count_before = rbd_dev->open_count--; 689 spin_unlock_irq(&rbd_dev->lock); 690 rbd_assert(open_count_before > 0); 691 692 put_device(&rbd_dev->dev); 693 } 694 695 static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg) 696 { 697 int ro; 698 699 if (get_user(ro, (int __user *)arg)) 700 return -EFAULT; 701 702 /* 703 * Both images mapped read-only and snapshots can't be marked 704 * read-write. 705 */ 706 if (!ro) { 707 if (rbd_is_ro(rbd_dev)) 708 return -EROFS; 709 710 rbd_assert(!rbd_is_snap(rbd_dev)); 711 } 712 713 /* Let blkdev_roset() handle it */ 714 return -ENOTTY; 715 } 716 717 static int rbd_ioctl(struct block_device *bdev, fmode_t mode, 718 unsigned int cmd, unsigned long arg) 719 { 720 struct rbd_device *rbd_dev = bdev->bd_disk->private_data; 721 int ret; 722 723 switch (cmd) { 724 case BLKROSET: 725 ret = rbd_ioctl_set_ro(rbd_dev, arg); 726 break; 727 default: 728 ret = -ENOTTY; 729 } 730 731 return ret; 732 } 733 734 #ifdef CONFIG_COMPAT 735 static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode, 736 unsigned int cmd, unsigned long arg) 737 { 738 return rbd_ioctl(bdev, mode, cmd, arg); 739 } 740 #endif /* CONFIG_COMPAT */ 741 742 static const struct block_device_operations rbd_bd_ops = { 743 .owner = THIS_MODULE, 744 .open = rbd_open, 745 .release = rbd_release, 746 .ioctl = rbd_ioctl, 747 #ifdef CONFIG_COMPAT 748 .compat_ioctl = rbd_compat_ioctl, 749 #endif 750 }; 751 752 /* 753 * Initialize an rbd client instance. Success or not, this function 754 * consumes ceph_opts. Caller holds client_mutex. 755 */ 756 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts) 757 { 758 struct rbd_client *rbdc; 759 int ret = -ENOMEM; 760 761 dout("%s:\n", __func__); 762 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL); 763 if (!rbdc) 764 goto out_opt; 765 766 kref_init(&rbdc->kref); 767 INIT_LIST_HEAD(&rbdc->node); 768 769 rbdc->client = ceph_create_client(ceph_opts, rbdc); 770 if (IS_ERR(rbdc->client)) 771 goto out_rbdc; 772 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */ 773 774 ret = ceph_open_session(rbdc->client); 775 if (ret < 0) 776 goto out_client; 777 778 spin_lock(&rbd_client_list_lock); 779 list_add_tail(&rbdc->node, &rbd_client_list); 780 spin_unlock(&rbd_client_list_lock); 781 782 dout("%s: rbdc %p\n", __func__, rbdc); 783 784 return rbdc; 785 out_client: 786 ceph_destroy_client(rbdc->client); 787 out_rbdc: 788 kfree(rbdc); 789 out_opt: 790 if (ceph_opts) 791 ceph_destroy_options(ceph_opts); 792 dout("%s: error %d\n", __func__, ret); 793 794 return ERR_PTR(ret); 795 } 796 797 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc) 798 { 799 kref_get(&rbdc->kref); 800 801 return rbdc; 802 } 803 804 /* 805 * Find a ceph client with specific addr and configuration. If 806 * found, bump its reference count. 807 */ 808 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts) 809 { 810 struct rbd_client *client_node; 811 bool found = false; 812 813 if (ceph_opts->flags & CEPH_OPT_NOSHARE) 814 return NULL; 815 816 spin_lock(&rbd_client_list_lock); 817 list_for_each_entry(client_node, &rbd_client_list, node) { 818 if (!ceph_compare_options(ceph_opts, client_node->client)) { 819 __rbd_get_client(client_node); 820 821 found = true; 822 break; 823 } 824 } 825 spin_unlock(&rbd_client_list_lock); 826 827 return found ? client_node : NULL; 828 } 829 830 /* 831 * (Per device) rbd map options 832 */ 833 enum { 834 Opt_queue_depth, 835 Opt_alloc_size, 836 Opt_lock_timeout, 837 /* int args above */ 838 Opt_pool_ns, 839 Opt_compression_hint, 840 /* string args above */ 841 Opt_read_only, 842 Opt_read_write, 843 Opt_lock_on_read, 844 Opt_exclusive, 845 Opt_notrim, 846 }; 847 848 enum { 849 Opt_compression_hint_none, 850 Opt_compression_hint_compressible, 851 Opt_compression_hint_incompressible, 852 }; 853 854 static const struct constant_table rbd_param_compression_hint[] = { 855 {"none", Opt_compression_hint_none}, 856 {"compressible", Opt_compression_hint_compressible}, 857 {"incompressible", Opt_compression_hint_incompressible}, 858 {} 859 }; 860 861 static const struct fs_parameter_spec rbd_parameters[] = { 862 fsparam_u32 ("alloc_size", Opt_alloc_size), 863 fsparam_enum ("compression_hint", Opt_compression_hint, 864 rbd_param_compression_hint), 865 fsparam_flag ("exclusive", Opt_exclusive), 866 fsparam_flag ("lock_on_read", Opt_lock_on_read), 867 fsparam_u32 ("lock_timeout", Opt_lock_timeout), 868 fsparam_flag ("notrim", Opt_notrim), 869 fsparam_string ("_pool_ns", Opt_pool_ns), 870 fsparam_u32 ("queue_depth", Opt_queue_depth), 871 fsparam_flag ("read_only", Opt_read_only), 872 fsparam_flag ("read_write", Opt_read_write), 873 fsparam_flag ("ro", Opt_read_only), 874 fsparam_flag ("rw", Opt_read_write), 875 {} 876 }; 877 878 struct rbd_options { 879 int queue_depth; 880 int alloc_size; 881 unsigned long lock_timeout; 882 bool read_only; 883 bool lock_on_read; 884 bool exclusive; 885 bool trim; 886 887 u32 alloc_hint_flags; /* CEPH_OSD_OP_ALLOC_HINT_FLAG_* */ 888 }; 889 890 #define RBD_QUEUE_DEPTH_DEFAULT BLKDEV_MAX_RQ 891 #define RBD_ALLOC_SIZE_DEFAULT (64 * 1024) 892 #define RBD_LOCK_TIMEOUT_DEFAULT 0 /* no timeout */ 893 #define RBD_READ_ONLY_DEFAULT false 894 #define RBD_LOCK_ON_READ_DEFAULT false 895 #define RBD_EXCLUSIVE_DEFAULT false 896 #define RBD_TRIM_DEFAULT true 897 898 struct rbd_parse_opts_ctx { 899 struct rbd_spec *spec; 900 struct ceph_options *copts; 901 struct rbd_options *opts; 902 }; 903 904 static char* obj_op_name(enum obj_operation_type op_type) 905 { 906 switch (op_type) { 907 case OBJ_OP_READ: 908 return "read"; 909 case OBJ_OP_WRITE: 910 return "write"; 911 case OBJ_OP_DISCARD: 912 return "discard"; 913 case OBJ_OP_ZEROOUT: 914 return "zeroout"; 915 default: 916 return "???"; 917 } 918 } 919 920 /* 921 * Destroy ceph client 922 * 923 * Caller must hold rbd_client_list_lock. 924 */ 925 static void rbd_client_release(struct kref *kref) 926 { 927 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref); 928 929 dout("%s: rbdc %p\n", __func__, rbdc); 930 spin_lock(&rbd_client_list_lock); 931 list_del(&rbdc->node); 932 spin_unlock(&rbd_client_list_lock); 933 934 ceph_destroy_client(rbdc->client); 935 kfree(rbdc); 936 } 937 938 /* 939 * Drop reference to ceph client node. If it's not referenced anymore, release 940 * it. 941 */ 942 static void rbd_put_client(struct rbd_client *rbdc) 943 { 944 if (rbdc) 945 kref_put(&rbdc->kref, rbd_client_release); 946 } 947 948 /* 949 * Get a ceph client with specific addr and configuration, if one does 950 * not exist create it. Either way, ceph_opts is consumed by this 951 * function. 952 */ 953 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts) 954 { 955 struct rbd_client *rbdc; 956 int ret; 957 958 mutex_lock(&client_mutex); 959 rbdc = rbd_client_find(ceph_opts); 960 if (rbdc) { 961 ceph_destroy_options(ceph_opts); 962 963 /* 964 * Using an existing client. Make sure ->pg_pools is up to 965 * date before we look up the pool id in do_rbd_add(). 966 */ 967 ret = ceph_wait_for_latest_osdmap(rbdc->client, 968 rbdc->client->options->mount_timeout); 969 if (ret) { 970 rbd_warn(NULL, "failed to get latest osdmap: %d", ret); 971 rbd_put_client(rbdc); 972 rbdc = ERR_PTR(ret); 973 } 974 } else { 975 rbdc = rbd_client_create(ceph_opts); 976 } 977 mutex_unlock(&client_mutex); 978 979 return rbdc; 980 } 981 982 static bool rbd_image_format_valid(u32 image_format) 983 { 984 return image_format == 1 || image_format == 2; 985 } 986 987 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk) 988 { 989 size_t size; 990 u32 snap_count; 991 992 /* The header has to start with the magic rbd header text */ 993 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT))) 994 return false; 995 996 /* The bio layer requires at least sector-sized I/O */ 997 998 if (ondisk->options.order < SECTOR_SHIFT) 999 return false; 1000 1001 /* If we use u64 in a few spots we may be able to loosen this */ 1002 1003 if (ondisk->options.order > 8 * sizeof (int) - 1) 1004 return false; 1005 1006 /* 1007 * The size of a snapshot header has to fit in a size_t, and 1008 * that limits the number of snapshots. 1009 */ 1010 snap_count = le32_to_cpu(ondisk->snap_count); 1011 size = SIZE_MAX - sizeof (struct ceph_snap_context); 1012 if (snap_count > size / sizeof (__le64)) 1013 return false; 1014 1015 /* 1016 * Not only that, but the size of the entire the snapshot 1017 * header must also be representable in a size_t. 1018 */ 1019 size -= snap_count * sizeof (__le64); 1020 if ((u64) size < le64_to_cpu(ondisk->snap_names_len)) 1021 return false; 1022 1023 return true; 1024 } 1025 1026 /* 1027 * returns the size of an object in the image 1028 */ 1029 static u32 rbd_obj_bytes(struct rbd_image_header *header) 1030 { 1031 return 1U << header->obj_order; 1032 } 1033 1034 static void rbd_init_layout(struct rbd_device *rbd_dev) 1035 { 1036 if (rbd_dev->header.stripe_unit == 0 || 1037 rbd_dev->header.stripe_count == 0) { 1038 rbd_dev->header.stripe_unit = rbd_obj_bytes(&rbd_dev->header); 1039 rbd_dev->header.stripe_count = 1; 1040 } 1041 1042 rbd_dev->layout.stripe_unit = rbd_dev->header.stripe_unit; 1043 rbd_dev->layout.stripe_count = rbd_dev->header.stripe_count; 1044 rbd_dev->layout.object_size = rbd_obj_bytes(&rbd_dev->header); 1045 rbd_dev->layout.pool_id = rbd_dev->header.data_pool_id == CEPH_NOPOOL ? 1046 rbd_dev->spec->pool_id : rbd_dev->header.data_pool_id; 1047 RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL); 1048 } 1049 1050 /* 1051 * Fill an rbd image header with information from the given format 1 1052 * on-disk header. 1053 */ 1054 static int rbd_header_from_disk(struct rbd_device *rbd_dev, 1055 struct rbd_image_header_ondisk *ondisk) 1056 { 1057 struct rbd_image_header *header = &rbd_dev->header; 1058 bool first_time = header->object_prefix == NULL; 1059 struct ceph_snap_context *snapc; 1060 char *object_prefix = NULL; 1061 char *snap_names = NULL; 1062 u64 *snap_sizes = NULL; 1063 u32 snap_count; 1064 int ret = -ENOMEM; 1065 u32 i; 1066 1067 /* Allocate this now to avoid having to handle failure below */ 1068 1069 if (first_time) { 1070 object_prefix = kstrndup(ondisk->object_prefix, 1071 sizeof(ondisk->object_prefix), 1072 GFP_KERNEL); 1073 if (!object_prefix) 1074 return -ENOMEM; 1075 } 1076 1077 /* Allocate the snapshot context and fill it in */ 1078 1079 snap_count = le32_to_cpu(ondisk->snap_count); 1080 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); 1081 if (!snapc) 1082 goto out_err; 1083 snapc->seq = le64_to_cpu(ondisk->snap_seq); 1084 if (snap_count) { 1085 struct rbd_image_snap_ondisk *snaps; 1086 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len); 1087 1088 /* We'll keep a copy of the snapshot names... */ 1089 1090 if (snap_names_len > (u64)SIZE_MAX) 1091 goto out_2big; 1092 snap_names = kmalloc(snap_names_len, GFP_KERNEL); 1093 if (!snap_names) 1094 goto out_err; 1095 1096 /* ...as well as the array of their sizes. */ 1097 snap_sizes = kmalloc_array(snap_count, 1098 sizeof(*header->snap_sizes), 1099 GFP_KERNEL); 1100 if (!snap_sizes) 1101 goto out_err; 1102 1103 /* 1104 * Copy the names, and fill in each snapshot's id 1105 * and size. 1106 * 1107 * Note that rbd_dev_v1_header_info() guarantees the 1108 * ondisk buffer we're working with has 1109 * snap_names_len bytes beyond the end of the 1110 * snapshot id array, this memcpy() is safe. 1111 */ 1112 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len); 1113 snaps = ondisk->snaps; 1114 for (i = 0; i < snap_count; i++) { 1115 snapc->snaps[i] = le64_to_cpu(snaps[i].id); 1116 snap_sizes[i] = le64_to_cpu(snaps[i].image_size); 1117 } 1118 } 1119 1120 /* We won't fail any more, fill in the header */ 1121 1122 if (first_time) { 1123 header->object_prefix = object_prefix; 1124 header->obj_order = ondisk->options.order; 1125 rbd_init_layout(rbd_dev); 1126 } else { 1127 ceph_put_snap_context(header->snapc); 1128 kfree(header->snap_names); 1129 kfree(header->snap_sizes); 1130 } 1131 1132 /* The remaining fields always get updated (when we refresh) */ 1133 1134 header->image_size = le64_to_cpu(ondisk->image_size); 1135 header->snapc = snapc; 1136 header->snap_names = snap_names; 1137 header->snap_sizes = snap_sizes; 1138 1139 return 0; 1140 out_2big: 1141 ret = -EIO; 1142 out_err: 1143 kfree(snap_sizes); 1144 kfree(snap_names); 1145 ceph_put_snap_context(snapc); 1146 kfree(object_prefix); 1147 1148 return ret; 1149 } 1150 1151 static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which) 1152 { 1153 const char *snap_name; 1154 1155 rbd_assert(which < rbd_dev->header.snapc->num_snaps); 1156 1157 /* Skip over names until we find the one we are looking for */ 1158 1159 snap_name = rbd_dev->header.snap_names; 1160 while (which--) 1161 snap_name += strlen(snap_name) + 1; 1162 1163 return kstrdup(snap_name, GFP_KERNEL); 1164 } 1165 1166 /* 1167 * Snapshot id comparison function for use with qsort()/bsearch(). 1168 * Note that result is for snapshots in *descending* order. 1169 */ 1170 static int snapid_compare_reverse(const void *s1, const void *s2) 1171 { 1172 u64 snap_id1 = *(u64 *)s1; 1173 u64 snap_id2 = *(u64 *)s2; 1174 1175 if (snap_id1 < snap_id2) 1176 return 1; 1177 return snap_id1 == snap_id2 ? 0 : -1; 1178 } 1179 1180 /* 1181 * Search a snapshot context to see if the given snapshot id is 1182 * present. 1183 * 1184 * Returns the position of the snapshot id in the array if it's found, 1185 * or BAD_SNAP_INDEX otherwise. 1186 * 1187 * Note: The snapshot array is in kept sorted (by the osd) in 1188 * reverse order, highest snapshot id first. 1189 */ 1190 static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id) 1191 { 1192 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 1193 u64 *found; 1194 1195 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps, 1196 sizeof (snap_id), snapid_compare_reverse); 1197 1198 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX; 1199 } 1200 1201 static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, 1202 u64 snap_id) 1203 { 1204 u32 which; 1205 const char *snap_name; 1206 1207 which = rbd_dev_snap_index(rbd_dev, snap_id); 1208 if (which == BAD_SNAP_INDEX) 1209 return ERR_PTR(-ENOENT); 1210 1211 snap_name = _rbd_dev_v1_snap_name(rbd_dev, which); 1212 return snap_name ? snap_name : ERR_PTR(-ENOMEM); 1213 } 1214 1215 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id) 1216 { 1217 if (snap_id == CEPH_NOSNAP) 1218 return RBD_SNAP_HEAD_NAME; 1219 1220 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 1221 if (rbd_dev->image_format == 1) 1222 return rbd_dev_v1_snap_name(rbd_dev, snap_id); 1223 1224 return rbd_dev_v2_snap_name(rbd_dev, snap_id); 1225 } 1226 1227 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 1228 u64 *snap_size) 1229 { 1230 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 1231 if (snap_id == CEPH_NOSNAP) { 1232 *snap_size = rbd_dev->header.image_size; 1233 } else if (rbd_dev->image_format == 1) { 1234 u32 which; 1235 1236 which = rbd_dev_snap_index(rbd_dev, snap_id); 1237 if (which == BAD_SNAP_INDEX) 1238 return -ENOENT; 1239 1240 *snap_size = rbd_dev->header.snap_sizes[which]; 1241 } else { 1242 u64 size = 0; 1243 int ret; 1244 1245 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size); 1246 if (ret) 1247 return ret; 1248 1249 *snap_size = size; 1250 } 1251 return 0; 1252 } 1253 1254 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev) 1255 { 1256 u64 snap_id = rbd_dev->spec->snap_id; 1257 u64 size = 0; 1258 int ret; 1259 1260 ret = rbd_snap_size(rbd_dev, snap_id, &size); 1261 if (ret) 1262 return ret; 1263 1264 rbd_dev->mapping.size = size; 1265 return 0; 1266 } 1267 1268 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev) 1269 { 1270 rbd_dev->mapping.size = 0; 1271 } 1272 1273 static void zero_bvec(struct bio_vec *bv) 1274 { 1275 void *buf; 1276 unsigned long flags; 1277 1278 buf = bvec_kmap_irq(bv, &flags); 1279 memset(buf, 0, bv->bv_len); 1280 flush_dcache_page(bv->bv_page); 1281 bvec_kunmap_irq(buf, &flags); 1282 } 1283 1284 static void zero_bios(struct ceph_bio_iter *bio_pos, u32 off, u32 bytes) 1285 { 1286 struct ceph_bio_iter it = *bio_pos; 1287 1288 ceph_bio_iter_advance(&it, off); 1289 ceph_bio_iter_advance_step(&it, bytes, ({ 1290 zero_bvec(&bv); 1291 })); 1292 } 1293 1294 static void zero_bvecs(struct ceph_bvec_iter *bvec_pos, u32 off, u32 bytes) 1295 { 1296 struct ceph_bvec_iter it = *bvec_pos; 1297 1298 ceph_bvec_iter_advance(&it, off); 1299 ceph_bvec_iter_advance_step(&it, bytes, ({ 1300 zero_bvec(&bv); 1301 })); 1302 } 1303 1304 /* 1305 * Zero a range in @obj_req data buffer defined by a bio (list) or 1306 * (private) bio_vec array. 1307 * 1308 * @off is relative to the start of the data buffer. 1309 */ 1310 static void rbd_obj_zero_range(struct rbd_obj_request *obj_req, u32 off, 1311 u32 bytes) 1312 { 1313 dout("%s %p data buf %u~%u\n", __func__, obj_req, off, bytes); 1314 1315 switch (obj_req->img_request->data_type) { 1316 case OBJ_REQUEST_BIO: 1317 zero_bios(&obj_req->bio_pos, off, bytes); 1318 break; 1319 case OBJ_REQUEST_BVECS: 1320 case OBJ_REQUEST_OWN_BVECS: 1321 zero_bvecs(&obj_req->bvec_pos, off, bytes); 1322 break; 1323 default: 1324 BUG(); 1325 } 1326 } 1327 1328 static void rbd_obj_request_destroy(struct kref *kref); 1329 static void rbd_obj_request_put(struct rbd_obj_request *obj_request) 1330 { 1331 rbd_assert(obj_request != NULL); 1332 dout("%s: obj %p (was %d)\n", __func__, obj_request, 1333 kref_read(&obj_request->kref)); 1334 kref_put(&obj_request->kref, rbd_obj_request_destroy); 1335 } 1336 1337 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request, 1338 struct rbd_obj_request *obj_request) 1339 { 1340 rbd_assert(obj_request->img_request == NULL); 1341 1342 /* Image request now owns object's original reference */ 1343 obj_request->img_request = img_request; 1344 dout("%s: img %p obj %p\n", __func__, img_request, obj_request); 1345 } 1346 1347 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request, 1348 struct rbd_obj_request *obj_request) 1349 { 1350 dout("%s: img %p obj %p\n", __func__, img_request, obj_request); 1351 list_del(&obj_request->ex.oe_item); 1352 rbd_assert(obj_request->img_request == img_request); 1353 rbd_obj_request_put(obj_request); 1354 } 1355 1356 static void rbd_osd_submit(struct ceph_osd_request *osd_req) 1357 { 1358 struct rbd_obj_request *obj_req = osd_req->r_priv; 1359 1360 dout("%s osd_req %p for obj_req %p objno %llu %llu~%llu\n", 1361 __func__, osd_req, obj_req, obj_req->ex.oe_objno, 1362 obj_req->ex.oe_off, obj_req->ex.oe_len); 1363 ceph_osdc_start_request(osd_req->r_osdc, osd_req, false); 1364 } 1365 1366 /* 1367 * The default/initial value for all image request flags is 0. Each 1368 * is conditionally set to 1 at image request initialization time 1369 * and currently never change thereafter. 1370 */ 1371 static void img_request_layered_set(struct rbd_img_request *img_request) 1372 { 1373 set_bit(IMG_REQ_LAYERED, &img_request->flags); 1374 } 1375 1376 static bool img_request_layered_test(struct rbd_img_request *img_request) 1377 { 1378 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0; 1379 } 1380 1381 static bool rbd_obj_is_entire(struct rbd_obj_request *obj_req) 1382 { 1383 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 1384 1385 return !obj_req->ex.oe_off && 1386 obj_req->ex.oe_len == rbd_dev->layout.object_size; 1387 } 1388 1389 static bool rbd_obj_is_tail(struct rbd_obj_request *obj_req) 1390 { 1391 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 1392 1393 return obj_req->ex.oe_off + obj_req->ex.oe_len == 1394 rbd_dev->layout.object_size; 1395 } 1396 1397 /* 1398 * Must be called after rbd_obj_calc_img_extents(). 1399 */ 1400 static bool rbd_obj_copyup_enabled(struct rbd_obj_request *obj_req) 1401 { 1402 if (!obj_req->num_img_extents || 1403 (rbd_obj_is_entire(obj_req) && 1404 !obj_req->img_request->snapc->num_snaps)) 1405 return false; 1406 1407 return true; 1408 } 1409 1410 static u64 rbd_obj_img_extents_bytes(struct rbd_obj_request *obj_req) 1411 { 1412 return ceph_file_extents_bytes(obj_req->img_extents, 1413 obj_req->num_img_extents); 1414 } 1415 1416 static bool rbd_img_is_write(struct rbd_img_request *img_req) 1417 { 1418 switch (img_req->op_type) { 1419 case OBJ_OP_READ: 1420 return false; 1421 case OBJ_OP_WRITE: 1422 case OBJ_OP_DISCARD: 1423 case OBJ_OP_ZEROOUT: 1424 return true; 1425 default: 1426 BUG(); 1427 } 1428 } 1429 1430 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req) 1431 { 1432 struct rbd_obj_request *obj_req = osd_req->r_priv; 1433 int result; 1434 1435 dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req, 1436 osd_req->r_result, obj_req); 1437 1438 /* 1439 * Writes aren't allowed to return a data payload. In some 1440 * guarded write cases (e.g. stat + zero on an empty object) 1441 * a stat response makes it through, but we don't care. 1442 */ 1443 if (osd_req->r_result > 0 && rbd_img_is_write(obj_req->img_request)) 1444 result = 0; 1445 else 1446 result = osd_req->r_result; 1447 1448 rbd_obj_handle_request(obj_req, result); 1449 } 1450 1451 static void rbd_osd_format_read(struct ceph_osd_request *osd_req) 1452 { 1453 struct rbd_obj_request *obj_request = osd_req->r_priv; 1454 struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev; 1455 struct ceph_options *opt = rbd_dev->rbd_client->client->options; 1456 1457 osd_req->r_flags = CEPH_OSD_FLAG_READ | opt->read_from_replica; 1458 osd_req->r_snapid = obj_request->img_request->snap_id; 1459 } 1460 1461 static void rbd_osd_format_write(struct ceph_osd_request *osd_req) 1462 { 1463 struct rbd_obj_request *obj_request = osd_req->r_priv; 1464 1465 osd_req->r_flags = CEPH_OSD_FLAG_WRITE; 1466 ktime_get_real_ts64(&osd_req->r_mtime); 1467 osd_req->r_data_offset = obj_request->ex.oe_off; 1468 } 1469 1470 static struct ceph_osd_request * 1471 __rbd_obj_add_osd_request(struct rbd_obj_request *obj_req, 1472 struct ceph_snap_context *snapc, int num_ops) 1473 { 1474 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 1475 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 1476 struct ceph_osd_request *req; 1477 const char *name_format = rbd_dev->image_format == 1 ? 1478 RBD_V1_DATA_FORMAT : RBD_V2_DATA_FORMAT; 1479 int ret; 1480 1481 req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, GFP_NOIO); 1482 if (!req) 1483 return ERR_PTR(-ENOMEM); 1484 1485 list_add_tail(&req->r_private_item, &obj_req->osd_reqs); 1486 req->r_callback = rbd_osd_req_callback; 1487 req->r_priv = obj_req; 1488 1489 /* 1490 * Data objects may be stored in a separate pool, but always in 1491 * the same namespace in that pool as the header in its pool. 1492 */ 1493 ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc); 1494 req->r_base_oloc.pool = rbd_dev->layout.pool_id; 1495 1496 ret = ceph_oid_aprintf(&req->r_base_oid, GFP_NOIO, name_format, 1497 rbd_dev->header.object_prefix, 1498 obj_req->ex.oe_objno); 1499 if (ret) 1500 return ERR_PTR(ret); 1501 1502 return req; 1503 } 1504 1505 static struct ceph_osd_request * 1506 rbd_obj_add_osd_request(struct rbd_obj_request *obj_req, int num_ops) 1507 { 1508 return __rbd_obj_add_osd_request(obj_req, obj_req->img_request->snapc, 1509 num_ops); 1510 } 1511 1512 static struct rbd_obj_request *rbd_obj_request_create(void) 1513 { 1514 struct rbd_obj_request *obj_request; 1515 1516 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO); 1517 if (!obj_request) 1518 return NULL; 1519 1520 ceph_object_extent_init(&obj_request->ex); 1521 INIT_LIST_HEAD(&obj_request->osd_reqs); 1522 mutex_init(&obj_request->state_mutex); 1523 kref_init(&obj_request->kref); 1524 1525 dout("%s %p\n", __func__, obj_request); 1526 return obj_request; 1527 } 1528 1529 static void rbd_obj_request_destroy(struct kref *kref) 1530 { 1531 struct rbd_obj_request *obj_request; 1532 struct ceph_osd_request *osd_req; 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 while (!list_empty(&obj_request->osd_reqs)) { 1540 osd_req = list_first_entry(&obj_request->osd_reqs, 1541 struct ceph_osd_request, r_private_item); 1542 list_del_init(&osd_req->r_private_item); 1543 ceph_osdc_put_request(osd_req); 1544 } 1545 1546 switch (obj_request->img_request->data_type) { 1547 case OBJ_REQUEST_NODATA: 1548 case OBJ_REQUEST_BIO: 1549 case OBJ_REQUEST_BVECS: 1550 break; /* Nothing to do */ 1551 case OBJ_REQUEST_OWN_BVECS: 1552 kfree(obj_request->bvec_pos.bvecs); 1553 break; 1554 default: 1555 BUG(); 1556 } 1557 1558 kfree(obj_request->img_extents); 1559 if (obj_request->copyup_bvecs) { 1560 for (i = 0; i < obj_request->copyup_bvec_count; i++) { 1561 if (obj_request->copyup_bvecs[i].bv_page) 1562 __free_page(obj_request->copyup_bvecs[i].bv_page); 1563 } 1564 kfree(obj_request->copyup_bvecs); 1565 } 1566 1567 kmem_cache_free(rbd_obj_request_cache, obj_request); 1568 } 1569 1570 /* It's OK to call this for a device with no parent */ 1571 1572 static void rbd_spec_put(struct rbd_spec *spec); 1573 static void rbd_dev_unparent(struct rbd_device *rbd_dev) 1574 { 1575 rbd_dev_remove_parent(rbd_dev); 1576 rbd_spec_put(rbd_dev->parent_spec); 1577 rbd_dev->parent_spec = NULL; 1578 rbd_dev->parent_overlap = 0; 1579 } 1580 1581 /* 1582 * Parent image reference counting is used to determine when an 1583 * image's parent fields can be safely torn down--after there are no 1584 * more in-flight requests to the parent image. When the last 1585 * reference is dropped, cleaning them up is safe. 1586 */ 1587 static void rbd_dev_parent_put(struct rbd_device *rbd_dev) 1588 { 1589 int counter; 1590 1591 if (!rbd_dev->parent_spec) 1592 return; 1593 1594 counter = atomic_dec_return_safe(&rbd_dev->parent_ref); 1595 if (counter > 0) 1596 return; 1597 1598 /* Last reference; clean up parent data structures */ 1599 1600 if (!counter) 1601 rbd_dev_unparent(rbd_dev); 1602 else 1603 rbd_warn(rbd_dev, "parent reference underflow"); 1604 } 1605 1606 /* 1607 * If an image has a non-zero parent overlap, get a reference to its 1608 * parent. 1609 * 1610 * Returns true if the rbd device has a parent with a non-zero 1611 * overlap and a reference for it was successfully taken, or 1612 * false otherwise. 1613 */ 1614 static bool rbd_dev_parent_get(struct rbd_device *rbd_dev) 1615 { 1616 int counter = 0; 1617 1618 if (!rbd_dev->parent_spec) 1619 return false; 1620 1621 if (rbd_dev->parent_overlap) 1622 counter = atomic_inc_return_safe(&rbd_dev->parent_ref); 1623 1624 if (counter < 0) 1625 rbd_warn(rbd_dev, "parent reference overflow"); 1626 1627 return counter > 0; 1628 } 1629 1630 static void rbd_img_request_init(struct rbd_img_request *img_request, 1631 struct rbd_device *rbd_dev, 1632 enum obj_operation_type op_type) 1633 { 1634 memset(img_request, 0, sizeof(*img_request)); 1635 1636 img_request->rbd_dev = rbd_dev; 1637 img_request->op_type = op_type; 1638 1639 INIT_LIST_HEAD(&img_request->lock_item); 1640 INIT_LIST_HEAD(&img_request->object_extents); 1641 mutex_init(&img_request->state_mutex); 1642 } 1643 1644 static void rbd_img_capture_header(struct rbd_img_request *img_req) 1645 { 1646 struct rbd_device *rbd_dev = img_req->rbd_dev; 1647 1648 lockdep_assert_held(&rbd_dev->header_rwsem); 1649 1650 if (rbd_img_is_write(img_req)) 1651 img_req->snapc = ceph_get_snap_context(rbd_dev->header.snapc); 1652 else 1653 img_req->snap_id = rbd_dev->spec->snap_id; 1654 1655 if (rbd_dev_parent_get(rbd_dev)) 1656 img_request_layered_set(img_req); 1657 } 1658 1659 static void rbd_img_request_destroy(struct rbd_img_request *img_request) 1660 { 1661 struct rbd_obj_request *obj_request; 1662 struct rbd_obj_request *next_obj_request; 1663 1664 dout("%s: img %p\n", __func__, img_request); 1665 1666 WARN_ON(!list_empty(&img_request->lock_item)); 1667 for_each_obj_request_safe(img_request, obj_request, next_obj_request) 1668 rbd_img_obj_request_del(img_request, obj_request); 1669 1670 if (img_request_layered_test(img_request)) 1671 rbd_dev_parent_put(img_request->rbd_dev); 1672 1673 if (rbd_img_is_write(img_request)) 1674 ceph_put_snap_context(img_request->snapc); 1675 1676 if (test_bit(IMG_REQ_CHILD, &img_request->flags)) 1677 kmem_cache_free(rbd_img_request_cache, img_request); 1678 } 1679 1680 #define BITS_PER_OBJ 2 1681 #define OBJS_PER_BYTE (BITS_PER_BYTE / BITS_PER_OBJ) 1682 #define OBJ_MASK ((1 << BITS_PER_OBJ) - 1) 1683 1684 static void __rbd_object_map_index(struct rbd_device *rbd_dev, u64 objno, 1685 u64 *index, u8 *shift) 1686 { 1687 u32 off; 1688 1689 rbd_assert(objno < rbd_dev->object_map_size); 1690 *index = div_u64_rem(objno, OBJS_PER_BYTE, &off); 1691 *shift = (OBJS_PER_BYTE - off - 1) * BITS_PER_OBJ; 1692 } 1693 1694 static u8 __rbd_object_map_get(struct rbd_device *rbd_dev, u64 objno) 1695 { 1696 u64 index; 1697 u8 shift; 1698 1699 lockdep_assert_held(&rbd_dev->object_map_lock); 1700 __rbd_object_map_index(rbd_dev, objno, &index, &shift); 1701 return (rbd_dev->object_map[index] >> shift) & OBJ_MASK; 1702 } 1703 1704 static void __rbd_object_map_set(struct rbd_device *rbd_dev, u64 objno, u8 val) 1705 { 1706 u64 index; 1707 u8 shift; 1708 u8 *p; 1709 1710 lockdep_assert_held(&rbd_dev->object_map_lock); 1711 rbd_assert(!(val & ~OBJ_MASK)); 1712 1713 __rbd_object_map_index(rbd_dev, objno, &index, &shift); 1714 p = &rbd_dev->object_map[index]; 1715 *p = (*p & ~(OBJ_MASK << shift)) | (val << shift); 1716 } 1717 1718 static u8 rbd_object_map_get(struct rbd_device *rbd_dev, u64 objno) 1719 { 1720 u8 state; 1721 1722 spin_lock(&rbd_dev->object_map_lock); 1723 state = __rbd_object_map_get(rbd_dev, objno); 1724 spin_unlock(&rbd_dev->object_map_lock); 1725 return state; 1726 } 1727 1728 static bool use_object_map(struct rbd_device *rbd_dev) 1729 { 1730 /* 1731 * An image mapped read-only can't use the object map -- it isn't 1732 * loaded because the header lock isn't acquired. Someone else can 1733 * write to the image and update the object map behind our back. 1734 * 1735 * A snapshot can't be written to, so using the object map is always 1736 * safe. 1737 */ 1738 if (!rbd_is_snap(rbd_dev) && rbd_is_ro(rbd_dev)) 1739 return false; 1740 1741 return ((rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) && 1742 !(rbd_dev->object_map_flags & RBD_FLAG_OBJECT_MAP_INVALID)); 1743 } 1744 1745 static bool rbd_object_map_may_exist(struct rbd_device *rbd_dev, u64 objno) 1746 { 1747 u8 state; 1748 1749 /* fall back to default logic if object map is disabled or invalid */ 1750 if (!use_object_map(rbd_dev)) 1751 return true; 1752 1753 state = rbd_object_map_get(rbd_dev, objno); 1754 return state != OBJECT_NONEXISTENT; 1755 } 1756 1757 static void rbd_object_map_name(struct rbd_device *rbd_dev, u64 snap_id, 1758 struct ceph_object_id *oid) 1759 { 1760 if (snap_id == CEPH_NOSNAP) 1761 ceph_oid_printf(oid, "%s%s", RBD_OBJECT_MAP_PREFIX, 1762 rbd_dev->spec->image_id); 1763 else 1764 ceph_oid_printf(oid, "%s%s.%016llx", RBD_OBJECT_MAP_PREFIX, 1765 rbd_dev->spec->image_id, snap_id); 1766 } 1767 1768 static int rbd_object_map_lock(struct rbd_device *rbd_dev) 1769 { 1770 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 1771 CEPH_DEFINE_OID_ONSTACK(oid); 1772 u8 lock_type; 1773 char *lock_tag; 1774 struct ceph_locker *lockers; 1775 u32 num_lockers; 1776 bool broke_lock = false; 1777 int ret; 1778 1779 rbd_object_map_name(rbd_dev, CEPH_NOSNAP, &oid); 1780 1781 again: 1782 ret = ceph_cls_lock(osdc, &oid, &rbd_dev->header_oloc, RBD_LOCK_NAME, 1783 CEPH_CLS_LOCK_EXCLUSIVE, "", "", "", 0); 1784 if (ret != -EBUSY || broke_lock) { 1785 if (ret == -EEXIST) 1786 ret = 0; /* already locked by myself */ 1787 if (ret) 1788 rbd_warn(rbd_dev, "failed to lock object map: %d", ret); 1789 return ret; 1790 } 1791 1792 ret = ceph_cls_lock_info(osdc, &oid, &rbd_dev->header_oloc, 1793 RBD_LOCK_NAME, &lock_type, &lock_tag, 1794 &lockers, &num_lockers); 1795 if (ret) { 1796 if (ret == -ENOENT) 1797 goto again; 1798 1799 rbd_warn(rbd_dev, "failed to get object map lockers: %d", ret); 1800 return ret; 1801 } 1802 1803 kfree(lock_tag); 1804 if (num_lockers == 0) 1805 goto again; 1806 1807 rbd_warn(rbd_dev, "breaking object map lock owned by %s%llu", 1808 ENTITY_NAME(lockers[0].id.name)); 1809 1810 ret = ceph_cls_break_lock(osdc, &oid, &rbd_dev->header_oloc, 1811 RBD_LOCK_NAME, lockers[0].id.cookie, 1812 &lockers[0].id.name); 1813 ceph_free_lockers(lockers, num_lockers); 1814 if (ret) { 1815 if (ret == -ENOENT) 1816 goto again; 1817 1818 rbd_warn(rbd_dev, "failed to break object map lock: %d", ret); 1819 return ret; 1820 } 1821 1822 broke_lock = true; 1823 goto again; 1824 } 1825 1826 static void rbd_object_map_unlock(struct rbd_device *rbd_dev) 1827 { 1828 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 1829 CEPH_DEFINE_OID_ONSTACK(oid); 1830 int ret; 1831 1832 rbd_object_map_name(rbd_dev, CEPH_NOSNAP, &oid); 1833 1834 ret = ceph_cls_unlock(osdc, &oid, &rbd_dev->header_oloc, RBD_LOCK_NAME, 1835 ""); 1836 if (ret && ret != -ENOENT) 1837 rbd_warn(rbd_dev, "failed to unlock object map: %d", ret); 1838 } 1839 1840 static int decode_object_map_header(void **p, void *end, u64 *object_map_size) 1841 { 1842 u8 struct_v; 1843 u32 struct_len; 1844 u32 header_len; 1845 void *header_end; 1846 int ret; 1847 1848 ceph_decode_32_safe(p, end, header_len, e_inval); 1849 header_end = *p + header_len; 1850 1851 ret = ceph_start_decoding(p, end, 1, "BitVector header", &struct_v, 1852 &struct_len); 1853 if (ret) 1854 return ret; 1855 1856 ceph_decode_64_safe(p, end, *object_map_size, e_inval); 1857 1858 *p = header_end; 1859 return 0; 1860 1861 e_inval: 1862 return -EINVAL; 1863 } 1864 1865 static int __rbd_object_map_load(struct rbd_device *rbd_dev) 1866 { 1867 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 1868 CEPH_DEFINE_OID_ONSTACK(oid); 1869 struct page **pages; 1870 void *p, *end; 1871 size_t reply_len; 1872 u64 num_objects; 1873 u64 object_map_bytes; 1874 u64 object_map_size; 1875 int num_pages; 1876 int ret; 1877 1878 rbd_assert(!rbd_dev->object_map && !rbd_dev->object_map_size); 1879 1880 num_objects = ceph_get_num_objects(&rbd_dev->layout, 1881 rbd_dev->mapping.size); 1882 object_map_bytes = DIV_ROUND_UP_ULL(num_objects * BITS_PER_OBJ, 1883 BITS_PER_BYTE); 1884 num_pages = calc_pages_for(0, object_map_bytes) + 1; 1885 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL); 1886 if (IS_ERR(pages)) 1887 return PTR_ERR(pages); 1888 1889 reply_len = num_pages * PAGE_SIZE; 1890 rbd_object_map_name(rbd_dev, rbd_dev->spec->snap_id, &oid); 1891 ret = ceph_osdc_call(osdc, &oid, &rbd_dev->header_oloc, 1892 "rbd", "object_map_load", CEPH_OSD_FLAG_READ, 1893 NULL, 0, pages, &reply_len); 1894 if (ret) 1895 goto out; 1896 1897 p = page_address(pages[0]); 1898 end = p + min(reply_len, (size_t)PAGE_SIZE); 1899 ret = decode_object_map_header(&p, end, &object_map_size); 1900 if (ret) 1901 goto out; 1902 1903 if (object_map_size != num_objects) { 1904 rbd_warn(rbd_dev, "object map size mismatch: %llu vs %llu", 1905 object_map_size, num_objects); 1906 ret = -EINVAL; 1907 goto out; 1908 } 1909 1910 if (offset_in_page(p) + object_map_bytes > reply_len) { 1911 ret = -EINVAL; 1912 goto out; 1913 } 1914 1915 rbd_dev->object_map = kvmalloc(object_map_bytes, GFP_KERNEL); 1916 if (!rbd_dev->object_map) { 1917 ret = -ENOMEM; 1918 goto out; 1919 } 1920 1921 rbd_dev->object_map_size = object_map_size; 1922 ceph_copy_from_page_vector(pages, rbd_dev->object_map, 1923 offset_in_page(p), object_map_bytes); 1924 1925 out: 1926 ceph_release_page_vector(pages, num_pages); 1927 return ret; 1928 } 1929 1930 static void rbd_object_map_free(struct rbd_device *rbd_dev) 1931 { 1932 kvfree(rbd_dev->object_map); 1933 rbd_dev->object_map = NULL; 1934 rbd_dev->object_map_size = 0; 1935 } 1936 1937 static int rbd_object_map_load(struct rbd_device *rbd_dev) 1938 { 1939 int ret; 1940 1941 ret = __rbd_object_map_load(rbd_dev); 1942 if (ret) 1943 return ret; 1944 1945 ret = rbd_dev_v2_get_flags(rbd_dev); 1946 if (ret) { 1947 rbd_object_map_free(rbd_dev); 1948 return ret; 1949 } 1950 1951 if (rbd_dev->object_map_flags & RBD_FLAG_OBJECT_MAP_INVALID) 1952 rbd_warn(rbd_dev, "object map is invalid"); 1953 1954 return 0; 1955 } 1956 1957 static int rbd_object_map_open(struct rbd_device *rbd_dev) 1958 { 1959 int ret; 1960 1961 ret = rbd_object_map_lock(rbd_dev); 1962 if (ret) 1963 return ret; 1964 1965 ret = rbd_object_map_load(rbd_dev); 1966 if (ret) { 1967 rbd_object_map_unlock(rbd_dev); 1968 return ret; 1969 } 1970 1971 return 0; 1972 } 1973 1974 static void rbd_object_map_close(struct rbd_device *rbd_dev) 1975 { 1976 rbd_object_map_free(rbd_dev); 1977 rbd_object_map_unlock(rbd_dev); 1978 } 1979 1980 /* 1981 * This function needs snap_id (or more precisely just something to 1982 * distinguish between HEAD and snapshot object maps), new_state and 1983 * current_state that were passed to rbd_object_map_update(). 1984 * 1985 * To avoid allocating and stashing a context we piggyback on the OSD 1986 * request. A HEAD update has two ops (assert_locked). For new_state 1987 * and current_state we decode our own object_map_update op, encoded in 1988 * rbd_cls_object_map_update(). 1989 */ 1990 static int rbd_object_map_update_finish(struct rbd_obj_request *obj_req, 1991 struct ceph_osd_request *osd_req) 1992 { 1993 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 1994 struct ceph_osd_data *osd_data; 1995 u64 objno; 1996 u8 state, new_state, current_state; 1997 bool has_current_state; 1998 void *p; 1999 2000 if (osd_req->r_result) 2001 return osd_req->r_result; 2002 2003 /* 2004 * Nothing to do for a snapshot object map. 2005 */ 2006 if (osd_req->r_num_ops == 1) 2007 return 0; 2008 2009 /* 2010 * Update in-memory HEAD object map. 2011 */ 2012 rbd_assert(osd_req->r_num_ops == 2); 2013 osd_data = osd_req_op_data(osd_req, 1, cls, request_data); 2014 rbd_assert(osd_data->type == CEPH_OSD_DATA_TYPE_PAGES); 2015 2016 p = page_address(osd_data->pages[0]); 2017 objno = ceph_decode_64(&p); 2018 rbd_assert(objno == obj_req->ex.oe_objno); 2019 rbd_assert(ceph_decode_64(&p) == objno + 1); 2020 new_state = ceph_decode_8(&p); 2021 has_current_state = ceph_decode_8(&p); 2022 if (has_current_state) 2023 current_state = ceph_decode_8(&p); 2024 2025 spin_lock(&rbd_dev->object_map_lock); 2026 state = __rbd_object_map_get(rbd_dev, objno); 2027 if (!has_current_state || current_state == state || 2028 (current_state == OBJECT_EXISTS && state == OBJECT_EXISTS_CLEAN)) 2029 __rbd_object_map_set(rbd_dev, objno, new_state); 2030 spin_unlock(&rbd_dev->object_map_lock); 2031 2032 return 0; 2033 } 2034 2035 static void rbd_object_map_callback(struct ceph_osd_request *osd_req) 2036 { 2037 struct rbd_obj_request *obj_req = osd_req->r_priv; 2038 int result; 2039 2040 dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req, 2041 osd_req->r_result, obj_req); 2042 2043 result = rbd_object_map_update_finish(obj_req, osd_req); 2044 rbd_obj_handle_request(obj_req, result); 2045 } 2046 2047 static bool update_needed(struct rbd_device *rbd_dev, u64 objno, u8 new_state) 2048 { 2049 u8 state = rbd_object_map_get(rbd_dev, objno); 2050 2051 if (state == new_state || 2052 (new_state == OBJECT_PENDING && state == OBJECT_NONEXISTENT) || 2053 (new_state == OBJECT_NONEXISTENT && state != OBJECT_PENDING)) 2054 return false; 2055 2056 return true; 2057 } 2058 2059 static int rbd_cls_object_map_update(struct ceph_osd_request *req, 2060 int which, u64 objno, u8 new_state, 2061 const u8 *current_state) 2062 { 2063 struct page **pages; 2064 void *p, *start; 2065 int ret; 2066 2067 ret = osd_req_op_cls_init(req, which, "rbd", "object_map_update"); 2068 if (ret) 2069 return ret; 2070 2071 pages = ceph_alloc_page_vector(1, GFP_NOIO); 2072 if (IS_ERR(pages)) 2073 return PTR_ERR(pages); 2074 2075 p = start = page_address(pages[0]); 2076 ceph_encode_64(&p, objno); 2077 ceph_encode_64(&p, objno + 1); 2078 ceph_encode_8(&p, new_state); 2079 if (current_state) { 2080 ceph_encode_8(&p, 1); 2081 ceph_encode_8(&p, *current_state); 2082 } else { 2083 ceph_encode_8(&p, 0); 2084 } 2085 2086 osd_req_op_cls_request_data_pages(req, which, pages, p - start, 0, 2087 false, true); 2088 return 0; 2089 } 2090 2091 /* 2092 * Return: 2093 * 0 - object map update sent 2094 * 1 - object map update isn't needed 2095 * <0 - error 2096 */ 2097 static int rbd_object_map_update(struct rbd_obj_request *obj_req, u64 snap_id, 2098 u8 new_state, const u8 *current_state) 2099 { 2100 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2101 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 2102 struct ceph_osd_request *req; 2103 int num_ops = 1; 2104 int which = 0; 2105 int ret; 2106 2107 if (snap_id == CEPH_NOSNAP) { 2108 if (!update_needed(rbd_dev, obj_req->ex.oe_objno, new_state)) 2109 return 1; 2110 2111 num_ops++; /* assert_locked */ 2112 } 2113 2114 req = ceph_osdc_alloc_request(osdc, NULL, num_ops, false, GFP_NOIO); 2115 if (!req) 2116 return -ENOMEM; 2117 2118 list_add_tail(&req->r_private_item, &obj_req->osd_reqs); 2119 req->r_callback = rbd_object_map_callback; 2120 req->r_priv = obj_req; 2121 2122 rbd_object_map_name(rbd_dev, snap_id, &req->r_base_oid); 2123 ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc); 2124 req->r_flags = CEPH_OSD_FLAG_WRITE; 2125 ktime_get_real_ts64(&req->r_mtime); 2126 2127 if (snap_id == CEPH_NOSNAP) { 2128 /* 2129 * Protect against possible race conditions during lock 2130 * ownership transitions. 2131 */ 2132 ret = ceph_cls_assert_locked(req, which++, RBD_LOCK_NAME, 2133 CEPH_CLS_LOCK_EXCLUSIVE, "", ""); 2134 if (ret) 2135 return ret; 2136 } 2137 2138 ret = rbd_cls_object_map_update(req, which, obj_req->ex.oe_objno, 2139 new_state, current_state); 2140 if (ret) 2141 return ret; 2142 2143 ret = ceph_osdc_alloc_messages(req, GFP_NOIO); 2144 if (ret) 2145 return ret; 2146 2147 ceph_osdc_start_request(osdc, req, false); 2148 return 0; 2149 } 2150 2151 static void prune_extents(struct ceph_file_extent *img_extents, 2152 u32 *num_img_extents, u64 overlap) 2153 { 2154 u32 cnt = *num_img_extents; 2155 2156 /* drop extents completely beyond the overlap */ 2157 while (cnt && img_extents[cnt - 1].fe_off >= overlap) 2158 cnt--; 2159 2160 if (cnt) { 2161 struct ceph_file_extent *ex = &img_extents[cnt - 1]; 2162 2163 /* trim final overlapping extent */ 2164 if (ex->fe_off + ex->fe_len > overlap) 2165 ex->fe_len = overlap - ex->fe_off; 2166 } 2167 2168 *num_img_extents = cnt; 2169 } 2170 2171 /* 2172 * Determine the byte range(s) covered by either just the object extent 2173 * or the entire object in the parent image. 2174 */ 2175 static int rbd_obj_calc_img_extents(struct rbd_obj_request *obj_req, 2176 bool entire) 2177 { 2178 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2179 int ret; 2180 2181 if (!rbd_dev->parent_overlap) 2182 return 0; 2183 2184 ret = ceph_extent_to_file(&rbd_dev->layout, obj_req->ex.oe_objno, 2185 entire ? 0 : obj_req->ex.oe_off, 2186 entire ? rbd_dev->layout.object_size : 2187 obj_req->ex.oe_len, 2188 &obj_req->img_extents, 2189 &obj_req->num_img_extents); 2190 if (ret) 2191 return ret; 2192 2193 prune_extents(obj_req->img_extents, &obj_req->num_img_extents, 2194 rbd_dev->parent_overlap); 2195 return 0; 2196 } 2197 2198 static void rbd_osd_setup_data(struct ceph_osd_request *osd_req, int which) 2199 { 2200 struct rbd_obj_request *obj_req = osd_req->r_priv; 2201 2202 switch (obj_req->img_request->data_type) { 2203 case OBJ_REQUEST_BIO: 2204 osd_req_op_extent_osd_data_bio(osd_req, which, 2205 &obj_req->bio_pos, 2206 obj_req->ex.oe_len); 2207 break; 2208 case OBJ_REQUEST_BVECS: 2209 case OBJ_REQUEST_OWN_BVECS: 2210 rbd_assert(obj_req->bvec_pos.iter.bi_size == 2211 obj_req->ex.oe_len); 2212 rbd_assert(obj_req->bvec_idx == obj_req->bvec_count); 2213 osd_req_op_extent_osd_data_bvec_pos(osd_req, which, 2214 &obj_req->bvec_pos); 2215 break; 2216 default: 2217 BUG(); 2218 } 2219 } 2220 2221 static int rbd_osd_setup_stat(struct ceph_osd_request *osd_req, int which) 2222 { 2223 struct page **pages; 2224 2225 /* 2226 * The response data for a STAT call consists of: 2227 * le64 length; 2228 * struct { 2229 * le32 tv_sec; 2230 * le32 tv_nsec; 2231 * } mtime; 2232 */ 2233 pages = ceph_alloc_page_vector(1, GFP_NOIO); 2234 if (IS_ERR(pages)) 2235 return PTR_ERR(pages); 2236 2237 osd_req_op_init(osd_req, which, CEPH_OSD_OP_STAT, 0); 2238 osd_req_op_raw_data_in_pages(osd_req, which, pages, 2239 8 + sizeof(struct ceph_timespec), 2240 0, false, true); 2241 return 0; 2242 } 2243 2244 static int rbd_osd_setup_copyup(struct ceph_osd_request *osd_req, int which, 2245 u32 bytes) 2246 { 2247 struct rbd_obj_request *obj_req = osd_req->r_priv; 2248 int ret; 2249 2250 ret = osd_req_op_cls_init(osd_req, which, "rbd", "copyup"); 2251 if (ret) 2252 return ret; 2253 2254 osd_req_op_cls_request_data_bvecs(osd_req, which, obj_req->copyup_bvecs, 2255 obj_req->copyup_bvec_count, bytes); 2256 return 0; 2257 } 2258 2259 static int rbd_obj_init_read(struct rbd_obj_request *obj_req) 2260 { 2261 obj_req->read_state = RBD_OBJ_READ_START; 2262 return 0; 2263 } 2264 2265 static void __rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req, 2266 int which) 2267 { 2268 struct rbd_obj_request *obj_req = osd_req->r_priv; 2269 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2270 u16 opcode; 2271 2272 if (!use_object_map(rbd_dev) || 2273 !(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST)) { 2274 osd_req_op_alloc_hint_init(osd_req, which++, 2275 rbd_dev->layout.object_size, 2276 rbd_dev->layout.object_size, 2277 rbd_dev->opts->alloc_hint_flags); 2278 } 2279 2280 if (rbd_obj_is_entire(obj_req)) 2281 opcode = CEPH_OSD_OP_WRITEFULL; 2282 else 2283 opcode = CEPH_OSD_OP_WRITE; 2284 2285 osd_req_op_extent_init(osd_req, which, opcode, 2286 obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0); 2287 rbd_osd_setup_data(osd_req, which); 2288 } 2289 2290 static int rbd_obj_init_write(struct rbd_obj_request *obj_req) 2291 { 2292 int ret; 2293 2294 /* reverse map the entire object onto the parent */ 2295 ret = rbd_obj_calc_img_extents(obj_req, true); 2296 if (ret) 2297 return ret; 2298 2299 if (rbd_obj_copyup_enabled(obj_req)) 2300 obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ENABLED; 2301 2302 obj_req->write_state = RBD_OBJ_WRITE_START; 2303 return 0; 2304 } 2305 2306 static u16 truncate_or_zero_opcode(struct rbd_obj_request *obj_req) 2307 { 2308 return rbd_obj_is_tail(obj_req) ? CEPH_OSD_OP_TRUNCATE : 2309 CEPH_OSD_OP_ZERO; 2310 } 2311 2312 static void __rbd_osd_setup_discard_ops(struct ceph_osd_request *osd_req, 2313 int which) 2314 { 2315 struct rbd_obj_request *obj_req = osd_req->r_priv; 2316 2317 if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents) { 2318 rbd_assert(obj_req->flags & RBD_OBJ_FLAG_DELETION); 2319 osd_req_op_init(osd_req, which, CEPH_OSD_OP_DELETE, 0); 2320 } else { 2321 osd_req_op_extent_init(osd_req, which, 2322 truncate_or_zero_opcode(obj_req), 2323 obj_req->ex.oe_off, obj_req->ex.oe_len, 2324 0, 0); 2325 } 2326 } 2327 2328 static int rbd_obj_init_discard(struct rbd_obj_request *obj_req) 2329 { 2330 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2331 u64 off, next_off; 2332 int ret; 2333 2334 /* 2335 * Align the range to alloc_size boundary and punt on discards 2336 * that are too small to free up any space. 2337 * 2338 * alloc_size == object_size && is_tail() is a special case for 2339 * filestore with filestore_punch_hole = false, needed to allow 2340 * truncate (in addition to delete). 2341 */ 2342 if (rbd_dev->opts->alloc_size != rbd_dev->layout.object_size || 2343 !rbd_obj_is_tail(obj_req)) { 2344 off = round_up(obj_req->ex.oe_off, rbd_dev->opts->alloc_size); 2345 next_off = round_down(obj_req->ex.oe_off + obj_req->ex.oe_len, 2346 rbd_dev->opts->alloc_size); 2347 if (off >= next_off) 2348 return 1; 2349 2350 dout("%s %p %llu~%llu -> %llu~%llu\n", __func__, 2351 obj_req, obj_req->ex.oe_off, obj_req->ex.oe_len, 2352 off, next_off - off); 2353 obj_req->ex.oe_off = off; 2354 obj_req->ex.oe_len = next_off - off; 2355 } 2356 2357 /* reverse map the entire object onto the parent */ 2358 ret = rbd_obj_calc_img_extents(obj_req, true); 2359 if (ret) 2360 return ret; 2361 2362 obj_req->flags |= RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT; 2363 if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents) 2364 obj_req->flags |= RBD_OBJ_FLAG_DELETION; 2365 2366 obj_req->write_state = RBD_OBJ_WRITE_START; 2367 return 0; 2368 } 2369 2370 static void __rbd_osd_setup_zeroout_ops(struct ceph_osd_request *osd_req, 2371 int which) 2372 { 2373 struct rbd_obj_request *obj_req = osd_req->r_priv; 2374 u16 opcode; 2375 2376 if (rbd_obj_is_entire(obj_req)) { 2377 if (obj_req->num_img_extents) { 2378 if (!(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED)) 2379 osd_req_op_init(osd_req, which++, 2380 CEPH_OSD_OP_CREATE, 0); 2381 opcode = CEPH_OSD_OP_TRUNCATE; 2382 } else { 2383 rbd_assert(obj_req->flags & RBD_OBJ_FLAG_DELETION); 2384 osd_req_op_init(osd_req, which++, 2385 CEPH_OSD_OP_DELETE, 0); 2386 opcode = 0; 2387 } 2388 } else { 2389 opcode = truncate_or_zero_opcode(obj_req); 2390 } 2391 2392 if (opcode) 2393 osd_req_op_extent_init(osd_req, which, opcode, 2394 obj_req->ex.oe_off, obj_req->ex.oe_len, 2395 0, 0); 2396 } 2397 2398 static int rbd_obj_init_zeroout(struct rbd_obj_request *obj_req) 2399 { 2400 int ret; 2401 2402 /* reverse map the entire object onto the parent */ 2403 ret = rbd_obj_calc_img_extents(obj_req, true); 2404 if (ret) 2405 return ret; 2406 2407 if (rbd_obj_copyup_enabled(obj_req)) 2408 obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ENABLED; 2409 if (!obj_req->num_img_extents) { 2410 obj_req->flags |= RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT; 2411 if (rbd_obj_is_entire(obj_req)) 2412 obj_req->flags |= RBD_OBJ_FLAG_DELETION; 2413 } 2414 2415 obj_req->write_state = RBD_OBJ_WRITE_START; 2416 return 0; 2417 } 2418 2419 static int count_write_ops(struct rbd_obj_request *obj_req) 2420 { 2421 struct rbd_img_request *img_req = obj_req->img_request; 2422 2423 switch (img_req->op_type) { 2424 case OBJ_OP_WRITE: 2425 if (!use_object_map(img_req->rbd_dev) || 2426 !(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST)) 2427 return 2; /* setallochint + write/writefull */ 2428 2429 return 1; /* write/writefull */ 2430 case OBJ_OP_DISCARD: 2431 return 1; /* delete/truncate/zero */ 2432 case OBJ_OP_ZEROOUT: 2433 if (rbd_obj_is_entire(obj_req) && obj_req->num_img_extents && 2434 !(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED)) 2435 return 2; /* create + truncate */ 2436 2437 return 1; /* delete/truncate/zero */ 2438 default: 2439 BUG(); 2440 } 2441 } 2442 2443 static void rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req, 2444 int which) 2445 { 2446 struct rbd_obj_request *obj_req = osd_req->r_priv; 2447 2448 switch (obj_req->img_request->op_type) { 2449 case OBJ_OP_WRITE: 2450 __rbd_osd_setup_write_ops(osd_req, which); 2451 break; 2452 case OBJ_OP_DISCARD: 2453 __rbd_osd_setup_discard_ops(osd_req, which); 2454 break; 2455 case OBJ_OP_ZEROOUT: 2456 __rbd_osd_setup_zeroout_ops(osd_req, which); 2457 break; 2458 default: 2459 BUG(); 2460 } 2461 } 2462 2463 /* 2464 * Prune the list of object requests (adjust offset and/or length, drop 2465 * redundant requests). Prepare object request state machines and image 2466 * request state machine for execution. 2467 */ 2468 static int __rbd_img_fill_request(struct rbd_img_request *img_req) 2469 { 2470 struct rbd_obj_request *obj_req, *next_obj_req; 2471 int ret; 2472 2473 for_each_obj_request_safe(img_req, obj_req, next_obj_req) { 2474 switch (img_req->op_type) { 2475 case OBJ_OP_READ: 2476 ret = rbd_obj_init_read(obj_req); 2477 break; 2478 case OBJ_OP_WRITE: 2479 ret = rbd_obj_init_write(obj_req); 2480 break; 2481 case OBJ_OP_DISCARD: 2482 ret = rbd_obj_init_discard(obj_req); 2483 break; 2484 case OBJ_OP_ZEROOUT: 2485 ret = rbd_obj_init_zeroout(obj_req); 2486 break; 2487 default: 2488 BUG(); 2489 } 2490 if (ret < 0) 2491 return ret; 2492 if (ret > 0) { 2493 rbd_img_obj_request_del(img_req, obj_req); 2494 continue; 2495 } 2496 } 2497 2498 img_req->state = RBD_IMG_START; 2499 return 0; 2500 } 2501 2502 union rbd_img_fill_iter { 2503 struct ceph_bio_iter bio_iter; 2504 struct ceph_bvec_iter bvec_iter; 2505 }; 2506 2507 struct rbd_img_fill_ctx { 2508 enum obj_request_type pos_type; 2509 union rbd_img_fill_iter *pos; 2510 union rbd_img_fill_iter iter; 2511 ceph_object_extent_fn_t set_pos_fn; 2512 ceph_object_extent_fn_t count_fn; 2513 ceph_object_extent_fn_t copy_fn; 2514 }; 2515 2516 static struct ceph_object_extent *alloc_object_extent(void *arg) 2517 { 2518 struct rbd_img_request *img_req = arg; 2519 struct rbd_obj_request *obj_req; 2520 2521 obj_req = rbd_obj_request_create(); 2522 if (!obj_req) 2523 return NULL; 2524 2525 rbd_img_obj_request_add(img_req, obj_req); 2526 return &obj_req->ex; 2527 } 2528 2529 /* 2530 * While su != os && sc == 1 is technically not fancy (it's the same 2531 * layout as su == os && sc == 1), we can't use the nocopy path for it 2532 * because ->set_pos_fn() should be called only once per object. 2533 * ceph_file_to_extents() invokes action_fn once per stripe unit, so 2534 * treat su != os && sc == 1 as fancy. 2535 */ 2536 static bool rbd_layout_is_fancy(struct ceph_file_layout *l) 2537 { 2538 return l->stripe_unit != l->object_size; 2539 } 2540 2541 static int rbd_img_fill_request_nocopy(struct rbd_img_request *img_req, 2542 struct ceph_file_extent *img_extents, 2543 u32 num_img_extents, 2544 struct rbd_img_fill_ctx *fctx) 2545 { 2546 u32 i; 2547 int ret; 2548 2549 img_req->data_type = fctx->pos_type; 2550 2551 /* 2552 * Create object requests and set each object request's starting 2553 * position in the provided bio (list) or bio_vec array. 2554 */ 2555 fctx->iter = *fctx->pos; 2556 for (i = 0; i < num_img_extents; i++) { 2557 ret = ceph_file_to_extents(&img_req->rbd_dev->layout, 2558 img_extents[i].fe_off, 2559 img_extents[i].fe_len, 2560 &img_req->object_extents, 2561 alloc_object_extent, img_req, 2562 fctx->set_pos_fn, &fctx->iter); 2563 if (ret) 2564 return ret; 2565 } 2566 2567 return __rbd_img_fill_request(img_req); 2568 } 2569 2570 /* 2571 * Map a list of image extents to a list of object extents, create the 2572 * corresponding object requests (normally each to a different object, 2573 * but not always) and add them to @img_req. For each object request, 2574 * set up its data descriptor to point to the corresponding chunk(s) of 2575 * @fctx->pos data buffer. 2576 * 2577 * Because ceph_file_to_extents() will merge adjacent object extents 2578 * together, each object request's data descriptor may point to multiple 2579 * different chunks of @fctx->pos data buffer. 2580 * 2581 * @fctx->pos data buffer is assumed to be large enough. 2582 */ 2583 static int rbd_img_fill_request(struct rbd_img_request *img_req, 2584 struct ceph_file_extent *img_extents, 2585 u32 num_img_extents, 2586 struct rbd_img_fill_ctx *fctx) 2587 { 2588 struct rbd_device *rbd_dev = img_req->rbd_dev; 2589 struct rbd_obj_request *obj_req; 2590 u32 i; 2591 int ret; 2592 2593 if (fctx->pos_type == OBJ_REQUEST_NODATA || 2594 !rbd_layout_is_fancy(&rbd_dev->layout)) 2595 return rbd_img_fill_request_nocopy(img_req, img_extents, 2596 num_img_extents, fctx); 2597 2598 img_req->data_type = OBJ_REQUEST_OWN_BVECS; 2599 2600 /* 2601 * Create object requests and determine ->bvec_count for each object 2602 * request. Note that ->bvec_count sum over all object requests may 2603 * be greater than the number of bio_vecs in the provided bio (list) 2604 * or bio_vec array because when mapped, those bio_vecs can straddle 2605 * stripe unit boundaries. 2606 */ 2607 fctx->iter = *fctx->pos; 2608 for (i = 0; i < num_img_extents; i++) { 2609 ret = ceph_file_to_extents(&rbd_dev->layout, 2610 img_extents[i].fe_off, 2611 img_extents[i].fe_len, 2612 &img_req->object_extents, 2613 alloc_object_extent, img_req, 2614 fctx->count_fn, &fctx->iter); 2615 if (ret) 2616 return ret; 2617 } 2618 2619 for_each_obj_request(img_req, obj_req) { 2620 obj_req->bvec_pos.bvecs = kmalloc_array(obj_req->bvec_count, 2621 sizeof(*obj_req->bvec_pos.bvecs), 2622 GFP_NOIO); 2623 if (!obj_req->bvec_pos.bvecs) 2624 return -ENOMEM; 2625 } 2626 2627 /* 2628 * Fill in each object request's private bio_vec array, splitting and 2629 * rearranging the provided bio_vecs in stripe unit chunks as needed. 2630 */ 2631 fctx->iter = *fctx->pos; 2632 for (i = 0; i < num_img_extents; i++) { 2633 ret = ceph_iterate_extents(&rbd_dev->layout, 2634 img_extents[i].fe_off, 2635 img_extents[i].fe_len, 2636 &img_req->object_extents, 2637 fctx->copy_fn, &fctx->iter); 2638 if (ret) 2639 return ret; 2640 } 2641 2642 return __rbd_img_fill_request(img_req); 2643 } 2644 2645 static int rbd_img_fill_nodata(struct rbd_img_request *img_req, 2646 u64 off, u64 len) 2647 { 2648 struct ceph_file_extent ex = { off, len }; 2649 union rbd_img_fill_iter dummy = {}; 2650 struct rbd_img_fill_ctx fctx = { 2651 .pos_type = OBJ_REQUEST_NODATA, 2652 .pos = &dummy, 2653 }; 2654 2655 return rbd_img_fill_request(img_req, &ex, 1, &fctx); 2656 } 2657 2658 static void set_bio_pos(struct ceph_object_extent *ex, u32 bytes, void *arg) 2659 { 2660 struct rbd_obj_request *obj_req = 2661 container_of(ex, struct rbd_obj_request, ex); 2662 struct ceph_bio_iter *it = arg; 2663 2664 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes); 2665 obj_req->bio_pos = *it; 2666 ceph_bio_iter_advance(it, bytes); 2667 } 2668 2669 static void count_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg) 2670 { 2671 struct rbd_obj_request *obj_req = 2672 container_of(ex, struct rbd_obj_request, ex); 2673 struct ceph_bio_iter *it = arg; 2674 2675 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes); 2676 ceph_bio_iter_advance_step(it, bytes, ({ 2677 obj_req->bvec_count++; 2678 })); 2679 2680 } 2681 2682 static void copy_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg) 2683 { 2684 struct rbd_obj_request *obj_req = 2685 container_of(ex, struct rbd_obj_request, ex); 2686 struct ceph_bio_iter *it = arg; 2687 2688 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes); 2689 ceph_bio_iter_advance_step(it, bytes, ({ 2690 obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv; 2691 obj_req->bvec_pos.iter.bi_size += bv.bv_len; 2692 })); 2693 } 2694 2695 static int __rbd_img_fill_from_bio(struct rbd_img_request *img_req, 2696 struct ceph_file_extent *img_extents, 2697 u32 num_img_extents, 2698 struct ceph_bio_iter *bio_pos) 2699 { 2700 struct rbd_img_fill_ctx fctx = { 2701 .pos_type = OBJ_REQUEST_BIO, 2702 .pos = (union rbd_img_fill_iter *)bio_pos, 2703 .set_pos_fn = set_bio_pos, 2704 .count_fn = count_bio_bvecs, 2705 .copy_fn = copy_bio_bvecs, 2706 }; 2707 2708 return rbd_img_fill_request(img_req, img_extents, num_img_extents, 2709 &fctx); 2710 } 2711 2712 static int rbd_img_fill_from_bio(struct rbd_img_request *img_req, 2713 u64 off, u64 len, struct bio *bio) 2714 { 2715 struct ceph_file_extent ex = { off, len }; 2716 struct ceph_bio_iter it = { .bio = bio, .iter = bio->bi_iter }; 2717 2718 return __rbd_img_fill_from_bio(img_req, &ex, 1, &it); 2719 } 2720 2721 static void set_bvec_pos(struct ceph_object_extent *ex, u32 bytes, void *arg) 2722 { 2723 struct rbd_obj_request *obj_req = 2724 container_of(ex, struct rbd_obj_request, ex); 2725 struct ceph_bvec_iter *it = arg; 2726 2727 obj_req->bvec_pos = *it; 2728 ceph_bvec_iter_shorten(&obj_req->bvec_pos, bytes); 2729 ceph_bvec_iter_advance(it, bytes); 2730 } 2731 2732 static void count_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg) 2733 { 2734 struct rbd_obj_request *obj_req = 2735 container_of(ex, struct rbd_obj_request, ex); 2736 struct ceph_bvec_iter *it = arg; 2737 2738 ceph_bvec_iter_advance_step(it, bytes, ({ 2739 obj_req->bvec_count++; 2740 })); 2741 } 2742 2743 static void copy_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg) 2744 { 2745 struct rbd_obj_request *obj_req = 2746 container_of(ex, struct rbd_obj_request, ex); 2747 struct ceph_bvec_iter *it = arg; 2748 2749 ceph_bvec_iter_advance_step(it, bytes, ({ 2750 obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv; 2751 obj_req->bvec_pos.iter.bi_size += bv.bv_len; 2752 })); 2753 } 2754 2755 static int __rbd_img_fill_from_bvecs(struct rbd_img_request *img_req, 2756 struct ceph_file_extent *img_extents, 2757 u32 num_img_extents, 2758 struct ceph_bvec_iter *bvec_pos) 2759 { 2760 struct rbd_img_fill_ctx fctx = { 2761 .pos_type = OBJ_REQUEST_BVECS, 2762 .pos = (union rbd_img_fill_iter *)bvec_pos, 2763 .set_pos_fn = set_bvec_pos, 2764 .count_fn = count_bvecs, 2765 .copy_fn = copy_bvecs, 2766 }; 2767 2768 return rbd_img_fill_request(img_req, img_extents, num_img_extents, 2769 &fctx); 2770 } 2771 2772 static int rbd_img_fill_from_bvecs(struct rbd_img_request *img_req, 2773 struct ceph_file_extent *img_extents, 2774 u32 num_img_extents, 2775 struct bio_vec *bvecs) 2776 { 2777 struct ceph_bvec_iter it = { 2778 .bvecs = bvecs, 2779 .iter = { .bi_size = ceph_file_extents_bytes(img_extents, 2780 num_img_extents) }, 2781 }; 2782 2783 return __rbd_img_fill_from_bvecs(img_req, img_extents, num_img_extents, 2784 &it); 2785 } 2786 2787 static void rbd_img_handle_request_work(struct work_struct *work) 2788 { 2789 struct rbd_img_request *img_req = 2790 container_of(work, struct rbd_img_request, work); 2791 2792 rbd_img_handle_request(img_req, img_req->work_result); 2793 } 2794 2795 static void rbd_img_schedule(struct rbd_img_request *img_req, int result) 2796 { 2797 INIT_WORK(&img_req->work, rbd_img_handle_request_work); 2798 img_req->work_result = result; 2799 queue_work(rbd_wq, &img_req->work); 2800 } 2801 2802 static bool rbd_obj_may_exist(struct rbd_obj_request *obj_req) 2803 { 2804 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2805 2806 if (rbd_object_map_may_exist(rbd_dev, obj_req->ex.oe_objno)) { 2807 obj_req->flags |= RBD_OBJ_FLAG_MAY_EXIST; 2808 return true; 2809 } 2810 2811 dout("%s %p objno %llu assuming dne\n", __func__, obj_req, 2812 obj_req->ex.oe_objno); 2813 return false; 2814 } 2815 2816 static int rbd_obj_read_object(struct rbd_obj_request *obj_req) 2817 { 2818 struct ceph_osd_request *osd_req; 2819 int ret; 2820 2821 osd_req = __rbd_obj_add_osd_request(obj_req, NULL, 1); 2822 if (IS_ERR(osd_req)) 2823 return PTR_ERR(osd_req); 2824 2825 osd_req_op_extent_init(osd_req, 0, CEPH_OSD_OP_READ, 2826 obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0); 2827 rbd_osd_setup_data(osd_req, 0); 2828 rbd_osd_format_read(osd_req); 2829 2830 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO); 2831 if (ret) 2832 return ret; 2833 2834 rbd_osd_submit(osd_req); 2835 return 0; 2836 } 2837 2838 static int rbd_obj_read_from_parent(struct rbd_obj_request *obj_req) 2839 { 2840 struct rbd_img_request *img_req = obj_req->img_request; 2841 struct rbd_device *parent = img_req->rbd_dev->parent; 2842 struct rbd_img_request *child_img_req; 2843 int ret; 2844 2845 child_img_req = kmem_cache_alloc(rbd_img_request_cache, GFP_NOIO); 2846 if (!child_img_req) 2847 return -ENOMEM; 2848 2849 rbd_img_request_init(child_img_req, parent, OBJ_OP_READ); 2850 __set_bit(IMG_REQ_CHILD, &child_img_req->flags); 2851 child_img_req->obj_request = obj_req; 2852 2853 down_read(&parent->header_rwsem); 2854 rbd_img_capture_header(child_img_req); 2855 up_read(&parent->header_rwsem); 2856 2857 dout("%s child_img_req %p for obj_req %p\n", __func__, child_img_req, 2858 obj_req); 2859 2860 if (!rbd_img_is_write(img_req)) { 2861 switch (img_req->data_type) { 2862 case OBJ_REQUEST_BIO: 2863 ret = __rbd_img_fill_from_bio(child_img_req, 2864 obj_req->img_extents, 2865 obj_req->num_img_extents, 2866 &obj_req->bio_pos); 2867 break; 2868 case OBJ_REQUEST_BVECS: 2869 case OBJ_REQUEST_OWN_BVECS: 2870 ret = __rbd_img_fill_from_bvecs(child_img_req, 2871 obj_req->img_extents, 2872 obj_req->num_img_extents, 2873 &obj_req->bvec_pos); 2874 break; 2875 default: 2876 BUG(); 2877 } 2878 } else { 2879 ret = rbd_img_fill_from_bvecs(child_img_req, 2880 obj_req->img_extents, 2881 obj_req->num_img_extents, 2882 obj_req->copyup_bvecs); 2883 } 2884 if (ret) { 2885 rbd_img_request_destroy(child_img_req); 2886 return ret; 2887 } 2888 2889 /* avoid parent chain recursion */ 2890 rbd_img_schedule(child_img_req, 0); 2891 return 0; 2892 } 2893 2894 static bool rbd_obj_advance_read(struct rbd_obj_request *obj_req, int *result) 2895 { 2896 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2897 int ret; 2898 2899 again: 2900 switch (obj_req->read_state) { 2901 case RBD_OBJ_READ_START: 2902 rbd_assert(!*result); 2903 2904 if (!rbd_obj_may_exist(obj_req)) { 2905 *result = -ENOENT; 2906 obj_req->read_state = RBD_OBJ_READ_OBJECT; 2907 goto again; 2908 } 2909 2910 ret = rbd_obj_read_object(obj_req); 2911 if (ret) { 2912 *result = ret; 2913 return true; 2914 } 2915 obj_req->read_state = RBD_OBJ_READ_OBJECT; 2916 return false; 2917 case RBD_OBJ_READ_OBJECT: 2918 if (*result == -ENOENT && rbd_dev->parent_overlap) { 2919 /* reverse map this object extent onto the parent */ 2920 ret = rbd_obj_calc_img_extents(obj_req, false); 2921 if (ret) { 2922 *result = ret; 2923 return true; 2924 } 2925 if (obj_req->num_img_extents) { 2926 ret = rbd_obj_read_from_parent(obj_req); 2927 if (ret) { 2928 *result = ret; 2929 return true; 2930 } 2931 obj_req->read_state = RBD_OBJ_READ_PARENT; 2932 return false; 2933 } 2934 } 2935 2936 /* 2937 * -ENOENT means a hole in the image -- zero-fill the entire 2938 * length of the request. A short read also implies zero-fill 2939 * to the end of the request. 2940 */ 2941 if (*result == -ENOENT) { 2942 rbd_obj_zero_range(obj_req, 0, obj_req->ex.oe_len); 2943 *result = 0; 2944 } else if (*result >= 0) { 2945 if (*result < obj_req->ex.oe_len) 2946 rbd_obj_zero_range(obj_req, *result, 2947 obj_req->ex.oe_len - *result); 2948 else 2949 rbd_assert(*result == obj_req->ex.oe_len); 2950 *result = 0; 2951 } 2952 return true; 2953 case RBD_OBJ_READ_PARENT: 2954 /* 2955 * The parent image is read only up to the overlap -- zero-fill 2956 * from the overlap to the end of the request. 2957 */ 2958 if (!*result) { 2959 u32 obj_overlap = rbd_obj_img_extents_bytes(obj_req); 2960 2961 if (obj_overlap < obj_req->ex.oe_len) 2962 rbd_obj_zero_range(obj_req, obj_overlap, 2963 obj_req->ex.oe_len - obj_overlap); 2964 } 2965 return true; 2966 default: 2967 BUG(); 2968 } 2969 } 2970 2971 static bool rbd_obj_write_is_noop(struct rbd_obj_request *obj_req) 2972 { 2973 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2974 2975 if (rbd_object_map_may_exist(rbd_dev, obj_req->ex.oe_objno)) 2976 obj_req->flags |= RBD_OBJ_FLAG_MAY_EXIST; 2977 2978 if (!(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST) && 2979 (obj_req->flags & RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT)) { 2980 dout("%s %p noop for nonexistent\n", __func__, obj_req); 2981 return true; 2982 } 2983 2984 return false; 2985 } 2986 2987 /* 2988 * Return: 2989 * 0 - object map update sent 2990 * 1 - object map update isn't needed 2991 * <0 - error 2992 */ 2993 static int rbd_obj_write_pre_object_map(struct rbd_obj_request *obj_req) 2994 { 2995 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 2996 u8 new_state; 2997 2998 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)) 2999 return 1; 3000 3001 if (obj_req->flags & RBD_OBJ_FLAG_DELETION) 3002 new_state = OBJECT_PENDING; 3003 else 3004 new_state = OBJECT_EXISTS; 3005 3006 return rbd_object_map_update(obj_req, CEPH_NOSNAP, new_state, NULL); 3007 } 3008 3009 static int rbd_obj_write_object(struct rbd_obj_request *obj_req) 3010 { 3011 struct ceph_osd_request *osd_req; 3012 int num_ops = count_write_ops(obj_req); 3013 int which = 0; 3014 int ret; 3015 3016 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) 3017 num_ops++; /* stat */ 3018 3019 osd_req = rbd_obj_add_osd_request(obj_req, num_ops); 3020 if (IS_ERR(osd_req)) 3021 return PTR_ERR(osd_req); 3022 3023 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) { 3024 ret = rbd_osd_setup_stat(osd_req, which++); 3025 if (ret) 3026 return ret; 3027 } 3028 3029 rbd_osd_setup_write_ops(osd_req, which); 3030 rbd_osd_format_write(osd_req); 3031 3032 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO); 3033 if (ret) 3034 return ret; 3035 3036 rbd_osd_submit(osd_req); 3037 return 0; 3038 } 3039 3040 /* 3041 * copyup_bvecs pages are never highmem pages 3042 */ 3043 static bool is_zero_bvecs(struct bio_vec *bvecs, u32 bytes) 3044 { 3045 struct ceph_bvec_iter it = { 3046 .bvecs = bvecs, 3047 .iter = { .bi_size = bytes }, 3048 }; 3049 3050 ceph_bvec_iter_advance_step(&it, bytes, ({ 3051 if (memchr_inv(page_address(bv.bv_page) + bv.bv_offset, 0, 3052 bv.bv_len)) 3053 return false; 3054 })); 3055 return true; 3056 } 3057 3058 #define MODS_ONLY U32_MAX 3059 3060 static int rbd_obj_copyup_empty_snapc(struct rbd_obj_request *obj_req, 3061 u32 bytes) 3062 { 3063 struct ceph_osd_request *osd_req; 3064 int ret; 3065 3066 dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes); 3067 rbd_assert(bytes > 0 && bytes != MODS_ONLY); 3068 3069 osd_req = __rbd_obj_add_osd_request(obj_req, &rbd_empty_snapc, 1); 3070 if (IS_ERR(osd_req)) 3071 return PTR_ERR(osd_req); 3072 3073 ret = rbd_osd_setup_copyup(osd_req, 0, bytes); 3074 if (ret) 3075 return ret; 3076 3077 rbd_osd_format_write(osd_req); 3078 3079 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO); 3080 if (ret) 3081 return ret; 3082 3083 rbd_osd_submit(osd_req); 3084 return 0; 3085 } 3086 3087 static int rbd_obj_copyup_current_snapc(struct rbd_obj_request *obj_req, 3088 u32 bytes) 3089 { 3090 struct ceph_osd_request *osd_req; 3091 int num_ops = count_write_ops(obj_req); 3092 int which = 0; 3093 int ret; 3094 3095 dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes); 3096 3097 if (bytes != MODS_ONLY) 3098 num_ops++; /* copyup */ 3099 3100 osd_req = rbd_obj_add_osd_request(obj_req, num_ops); 3101 if (IS_ERR(osd_req)) 3102 return PTR_ERR(osd_req); 3103 3104 if (bytes != MODS_ONLY) { 3105 ret = rbd_osd_setup_copyup(osd_req, which++, bytes); 3106 if (ret) 3107 return ret; 3108 } 3109 3110 rbd_osd_setup_write_ops(osd_req, which); 3111 rbd_osd_format_write(osd_req); 3112 3113 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO); 3114 if (ret) 3115 return ret; 3116 3117 rbd_osd_submit(osd_req); 3118 return 0; 3119 } 3120 3121 static int setup_copyup_bvecs(struct rbd_obj_request *obj_req, u64 obj_overlap) 3122 { 3123 u32 i; 3124 3125 rbd_assert(!obj_req->copyup_bvecs); 3126 obj_req->copyup_bvec_count = calc_pages_for(0, obj_overlap); 3127 obj_req->copyup_bvecs = kcalloc(obj_req->copyup_bvec_count, 3128 sizeof(*obj_req->copyup_bvecs), 3129 GFP_NOIO); 3130 if (!obj_req->copyup_bvecs) 3131 return -ENOMEM; 3132 3133 for (i = 0; i < obj_req->copyup_bvec_count; i++) { 3134 unsigned int len = min(obj_overlap, (u64)PAGE_SIZE); 3135 3136 obj_req->copyup_bvecs[i].bv_page = alloc_page(GFP_NOIO); 3137 if (!obj_req->copyup_bvecs[i].bv_page) 3138 return -ENOMEM; 3139 3140 obj_req->copyup_bvecs[i].bv_offset = 0; 3141 obj_req->copyup_bvecs[i].bv_len = len; 3142 obj_overlap -= len; 3143 } 3144 3145 rbd_assert(!obj_overlap); 3146 return 0; 3147 } 3148 3149 /* 3150 * The target object doesn't exist. Read the data for the entire 3151 * target object up to the overlap point (if any) from the parent, 3152 * so we can use it for a copyup. 3153 */ 3154 static int rbd_obj_copyup_read_parent(struct rbd_obj_request *obj_req) 3155 { 3156 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 3157 int ret; 3158 3159 rbd_assert(obj_req->num_img_extents); 3160 prune_extents(obj_req->img_extents, &obj_req->num_img_extents, 3161 rbd_dev->parent_overlap); 3162 if (!obj_req->num_img_extents) { 3163 /* 3164 * The overlap has become 0 (most likely because the 3165 * image has been flattened). Re-submit the original write 3166 * request -- pass MODS_ONLY since the copyup isn't needed 3167 * anymore. 3168 */ 3169 return rbd_obj_copyup_current_snapc(obj_req, MODS_ONLY); 3170 } 3171 3172 ret = setup_copyup_bvecs(obj_req, rbd_obj_img_extents_bytes(obj_req)); 3173 if (ret) 3174 return ret; 3175 3176 return rbd_obj_read_from_parent(obj_req); 3177 } 3178 3179 static void rbd_obj_copyup_object_maps(struct rbd_obj_request *obj_req) 3180 { 3181 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 3182 struct ceph_snap_context *snapc = obj_req->img_request->snapc; 3183 u8 new_state; 3184 u32 i; 3185 int ret; 3186 3187 rbd_assert(!obj_req->pending.result && !obj_req->pending.num_pending); 3188 3189 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)) 3190 return; 3191 3192 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ZEROS) 3193 return; 3194 3195 for (i = 0; i < snapc->num_snaps; i++) { 3196 if ((rbd_dev->header.features & RBD_FEATURE_FAST_DIFF) && 3197 i + 1 < snapc->num_snaps) 3198 new_state = OBJECT_EXISTS_CLEAN; 3199 else 3200 new_state = OBJECT_EXISTS; 3201 3202 ret = rbd_object_map_update(obj_req, snapc->snaps[i], 3203 new_state, NULL); 3204 if (ret < 0) { 3205 obj_req->pending.result = ret; 3206 return; 3207 } 3208 3209 rbd_assert(!ret); 3210 obj_req->pending.num_pending++; 3211 } 3212 } 3213 3214 static void rbd_obj_copyup_write_object(struct rbd_obj_request *obj_req) 3215 { 3216 u32 bytes = rbd_obj_img_extents_bytes(obj_req); 3217 int ret; 3218 3219 rbd_assert(!obj_req->pending.result && !obj_req->pending.num_pending); 3220 3221 /* 3222 * Only send non-zero copyup data to save some I/O and network 3223 * bandwidth -- zero copyup data is equivalent to the object not 3224 * existing. 3225 */ 3226 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ZEROS) 3227 bytes = 0; 3228 3229 if (obj_req->img_request->snapc->num_snaps && bytes > 0) { 3230 /* 3231 * Send a copyup request with an empty snapshot context to 3232 * deep-copyup the object through all existing snapshots. 3233 * A second request with the current snapshot context will be 3234 * sent for the actual modification. 3235 */ 3236 ret = rbd_obj_copyup_empty_snapc(obj_req, bytes); 3237 if (ret) { 3238 obj_req->pending.result = ret; 3239 return; 3240 } 3241 3242 obj_req->pending.num_pending++; 3243 bytes = MODS_ONLY; 3244 } 3245 3246 ret = rbd_obj_copyup_current_snapc(obj_req, bytes); 3247 if (ret) { 3248 obj_req->pending.result = ret; 3249 return; 3250 } 3251 3252 obj_req->pending.num_pending++; 3253 } 3254 3255 static bool rbd_obj_advance_copyup(struct rbd_obj_request *obj_req, int *result) 3256 { 3257 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 3258 int ret; 3259 3260 again: 3261 switch (obj_req->copyup_state) { 3262 case RBD_OBJ_COPYUP_START: 3263 rbd_assert(!*result); 3264 3265 ret = rbd_obj_copyup_read_parent(obj_req); 3266 if (ret) { 3267 *result = ret; 3268 return true; 3269 } 3270 if (obj_req->num_img_extents) 3271 obj_req->copyup_state = RBD_OBJ_COPYUP_READ_PARENT; 3272 else 3273 obj_req->copyup_state = RBD_OBJ_COPYUP_WRITE_OBJECT; 3274 return false; 3275 case RBD_OBJ_COPYUP_READ_PARENT: 3276 if (*result) 3277 return true; 3278 3279 if (is_zero_bvecs(obj_req->copyup_bvecs, 3280 rbd_obj_img_extents_bytes(obj_req))) { 3281 dout("%s %p detected zeros\n", __func__, obj_req); 3282 obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ZEROS; 3283 } 3284 3285 rbd_obj_copyup_object_maps(obj_req); 3286 if (!obj_req->pending.num_pending) { 3287 *result = obj_req->pending.result; 3288 obj_req->copyup_state = RBD_OBJ_COPYUP_OBJECT_MAPS; 3289 goto again; 3290 } 3291 obj_req->copyup_state = __RBD_OBJ_COPYUP_OBJECT_MAPS; 3292 return false; 3293 case __RBD_OBJ_COPYUP_OBJECT_MAPS: 3294 if (!pending_result_dec(&obj_req->pending, result)) 3295 return false; 3296 fallthrough; 3297 case RBD_OBJ_COPYUP_OBJECT_MAPS: 3298 if (*result) { 3299 rbd_warn(rbd_dev, "snap object map update failed: %d", 3300 *result); 3301 return true; 3302 } 3303 3304 rbd_obj_copyup_write_object(obj_req); 3305 if (!obj_req->pending.num_pending) { 3306 *result = obj_req->pending.result; 3307 obj_req->copyup_state = RBD_OBJ_COPYUP_WRITE_OBJECT; 3308 goto again; 3309 } 3310 obj_req->copyup_state = __RBD_OBJ_COPYUP_WRITE_OBJECT; 3311 return false; 3312 case __RBD_OBJ_COPYUP_WRITE_OBJECT: 3313 if (!pending_result_dec(&obj_req->pending, result)) 3314 return false; 3315 fallthrough; 3316 case RBD_OBJ_COPYUP_WRITE_OBJECT: 3317 return true; 3318 default: 3319 BUG(); 3320 } 3321 } 3322 3323 /* 3324 * Return: 3325 * 0 - object map update sent 3326 * 1 - object map update isn't needed 3327 * <0 - error 3328 */ 3329 static int rbd_obj_write_post_object_map(struct rbd_obj_request *obj_req) 3330 { 3331 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 3332 u8 current_state = OBJECT_PENDING; 3333 3334 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)) 3335 return 1; 3336 3337 if (!(obj_req->flags & RBD_OBJ_FLAG_DELETION)) 3338 return 1; 3339 3340 return rbd_object_map_update(obj_req, CEPH_NOSNAP, OBJECT_NONEXISTENT, 3341 ¤t_state); 3342 } 3343 3344 static bool rbd_obj_advance_write(struct rbd_obj_request *obj_req, int *result) 3345 { 3346 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev; 3347 int ret; 3348 3349 again: 3350 switch (obj_req->write_state) { 3351 case RBD_OBJ_WRITE_START: 3352 rbd_assert(!*result); 3353 3354 if (rbd_obj_write_is_noop(obj_req)) 3355 return true; 3356 3357 ret = rbd_obj_write_pre_object_map(obj_req); 3358 if (ret < 0) { 3359 *result = ret; 3360 return true; 3361 } 3362 obj_req->write_state = RBD_OBJ_WRITE_PRE_OBJECT_MAP; 3363 if (ret > 0) 3364 goto again; 3365 return false; 3366 case RBD_OBJ_WRITE_PRE_OBJECT_MAP: 3367 if (*result) { 3368 rbd_warn(rbd_dev, "pre object map update failed: %d", 3369 *result); 3370 return true; 3371 } 3372 ret = rbd_obj_write_object(obj_req); 3373 if (ret) { 3374 *result = ret; 3375 return true; 3376 } 3377 obj_req->write_state = RBD_OBJ_WRITE_OBJECT; 3378 return false; 3379 case RBD_OBJ_WRITE_OBJECT: 3380 if (*result == -ENOENT) { 3381 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) { 3382 *result = 0; 3383 obj_req->copyup_state = RBD_OBJ_COPYUP_START; 3384 obj_req->write_state = __RBD_OBJ_WRITE_COPYUP; 3385 goto again; 3386 } 3387 /* 3388 * On a non-existent object: 3389 * delete - -ENOENT, truncate/zero - 0 3390 */ 3391 if (obj_req->flags & RBD_OBJ_FLAG_DELETION) 3392 *result = 0; 3393 } 3394 if (*result) 3395 return true; 3396 3397 obj_req->write_state = RBD_OBJ_WRITE_COPYUP; 3398 goto again; 3399 case __RBD_OBJ_WRITE_COPYUP: 3400 if (!rbd_obj_advance_copyup(obj_req, result)) 3401 return false; 3402 fallthrough; 3403 case RBD_OBJ_WRITE_COPYUP: 3404 if (*result) { 3405 rbd_warn(rbd_dev, "copyup failed: %d", *result); 3406 return true; 3407 } 3408 ret = rbd_obj_write_post_object_map(obj_req); 3409 if (ret < 0) { 3410 *result = ret; 3411 return true; 3412 } 3413 obj_req->write_state = RBD_OBJ_WRITE_POST_OBJECT_MAP; 3414 if (ret > 0) 3415 goto again; 3416 return false; 3417 case RBD_OBJ_WRITE_POST_OBJECT_MAP: 3418 if (*result) 3419 rbd_warn(rbd_dev, "post object map update failed: %d", 3420 *result); 3421 return true; 3422 default: 3423 BUG(); 3424 } 3425 } 3426 3427 /* 3428 * Return true if @obj_req is completed. 3429 */ 3430 static bool __rbd_obj_handle_request(struct rbd_obj_request *obj_req, 3431 int *result) 3432 { 3433 struct rbd_img_request *img_req = obj_req->img_request; 3434 struct rbd_device *rbd_dev = img_req->rbd_dev; 3435 bool done; 3436 3437 mutex_lock(&obj_req->state_mutex); 3438 if (!rbd_img_is_write(img_req)) 3439 done = rbd_obj_advance_read(obj_req, result); 3440 else 3441 done = rbd_obj_advance_write(obj_req, result); 3442 mutex_unlock(&obj_req->state_mutex); 3443 3444 if (done && *result) { 3445 rbd_assert(*result < 0); 3446 rbd_warn(rbd_dev, "%s at objno %llu %llu~%llu result %d", 3447 obj_op_name(img_req->op_type), obj_req->ex.oe_objno, 3448 obj_req->ex.oe_off, obj_req->ex.oe_len, *result); 3449 } 3450 return done; 3451 } 3452 3453 /* 3454 * This is open-coded in rbd_img_handle_request() to avoid parent chain 3455 * recursion. 3456 */ 3457 static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result) 3458 { 3459 if (__rbd_obj_handle_request(obj_req, &result)) 3460 rbd_img_handle_request(obj_req->img_request, result); 3461 } 3462 3463 static bool need_exclusive_lock(struct rbd_img_request *img_req) 3464 { 3465 struct rbd_device *rbd_dev = img_req->rbd_dev; 3466 3467 if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) 3468 return false; 3469 3470 if (rbd_is_ro(rbd_dev)) 3471 return false; 3472 3473 rbd_assert(!test_bit(IMG_REQ_CHILD, &img_req->flags)); 3474 if (rbd_dev->opts->lock_on_read || 3475 (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)) 3476 return true; 3477 3478 return rbd_img_is_write(img_req); 3479 } 3480 3481 static bool rbd_lock_add_request(struct rbd_img_request *img_req) 3482 { 3483 struct rbd_device *rbd_dev = img_req->rbd_dev; 3484 bool locked; 3485 3486 lockdep_assert_held(&rbd_dev->lock_rwsem); 3487 locked = rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED; 3488 spin_lock(&rbd_dev->lock_lists_lock); 3489 rbd_assert(list_empty(&img_req->lock_item)); 3490 if (!locked) 3491 list_add_tail(&img_req->lock_item, &rbd_dev->acquiring_list); 3492 else 3493 list_add_tail(&img_req->lock_item, &rbd_dev->running_list); 3494 spin_unlock(&rbd_dev->lock_lists_lock); 3495 return locked; 3496 } 3497 3498 static void rbd_lock_del_request(struct rbd_img_request *img_req) 3499 { 3500 struct rbd_device *rbd_dev = img_req->rbd_dev; 3501 bool need_wakeup; 3502 3503 lockdep_assert_held(&rbd_dev->lock_rwsem); 3504 spin_lock(&rbd_dev->lock_lists_lock); 3505 rbd_assert(!list_empty(&img_req->lock_item)); 3506 list_del_init(&img_req->lock_item); 3507 need_wakeup = (rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING && 3508 list_empty(&rbd_dev->running_list)); 3509 spin_unlock(&rbd_dev->lock_lists_lock); 3510 if (need_wakeup) 3511 complete(&rbd_dev->releasing_wait); 3512 } 3513 3514 static int rbd_img_exclusive_lock(struct rbd_img_request *img_req) 3515 { 3516 struct rbd_device *rbd_dev = img_req->rbd_dev; 3517 3518 if (!need_exclusive_lock(img_req)) 3519 return 1; 3520 3521 if (rbd_lock_add_request(img_req)) 3522 return 1; 3523 3524 if (rbd_dev->opts->exclusive) { 3525 WARN_ON(1); /* lock got released? */ 3526 return -EROFS; 3527 } 3528 3529 /* 3530 * Note the use of mod_delayed_work() in rbd_acquire_lock() 3531 * and cancel_delayed_work() in wake_lock_waiters(). 3532 */ 3533 dout("%s rbd_dev %p queueing lock_dwork\n", __func__, rbd_dev); 3534 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0); 3535 return 0; 3536 } 3537 3538 static void rbd_img_object_requests(struct rbd_img_request *img_req) 3539 { 3540 struct rbd_obj_request *obj_req; 3541 3542 rbd_assert(!img_req->pending.result && !img_req->pending.num_pending); 3543 3544 for_each_obj_request(img_req, obj_req) { 3545 int result = 0; 3546 3547 if (__rbd_obj_handle_request(obj_req, &result)) { 3548 if (result) { 3549 img_req->pending.result = result; 3550 return; 3551 } 3552 } else { 3553 img_req->pending.num_pending++; 3554 } 3555 } 3556 } 3557 3558 static bool rbd_img_advance(struct rbd_img_request *img_req, int *result) 3559 { 3560 struct rbd_device *rbd_dev = img_req->rbd_dev; 3561 int ret; 3562 3563 again: 3564 switch (img_req->state) { 3565 case RBD_IMG_START: 3566 rbd_assert(!*result); 3567 3568 ret = rbd_img_exclusive_lock(img_req); 3569 if (ret < 0) { 3570 *result = ret; 3571 return true; 3572 } 3573 img_req->state = RBD_IMG_EXCLUSIVE_LOCK; 3574 if (ret > 0) 3575 goto again; 3576 return false; 3577 case RBD_IMG_EXCLUSIVE_LOCK: 3578 if (*result) 3579 return true; 3580 3581 rbd_assert(!need_exclusive_lock(img_req) || 3582 __rbd_is_lock_owner(rbd_dev)); 3583 3584 rbd_img_object_requests(img_req); 3585 if (!img_req->pending.num_pending) { 3586 *result = img_req->pending.result; 3587 img_req->state = RBD_IMG_OBJECT_REQUESTS; 3588 goto again; 3589 } 3590 img_req->state = __RBD_IMG_OBJECT_REQUESTS; 3591 return false; 3592 case __RBD_IMG_OBJECT_REQUESTS: 3593 if (!pending_result_dec(&img_req->pending, result)) 3594 return false; 3595 fallthrough; 3596 case RBD_IMG_OBJECT_REQUESTS: 3597 return true; 3598 default: 3599 BUG(); 3600 } 3601 } 3602 3603 /* 3604 * Return true if @img_req is completed. 3605 */ 3606 static bool __rbd_img_handle_request(struct rbd_img_request *img_req, 3607 int *result) 3608 { 3609 struct rbd_device *rbd_dev = img_req->rbd_dev; 3610 bool done; 3611 3612 if (need_exclusive_lock(img_req)) { 3613 down_read(&rbd_dev->lock_rwsem); 3614 mutex_lock(&img_req->state_mutex); 3615 done = rbd_img_advance(img_req, result); 3616 if (done) 3617 rbd_lock_del_request(img_req); 3618 mutex_unlock(&img_req->state_mutex); 3619 up_read(&rbd_dev->lock_rwsem); 3620 } else { 3621 mutex_lock(&img_req->state_mutex); 3622 done = rbd_img_advance(img_req, result); 3623 mutex_unlock(&img_req->state_mutex); 3624 } 3625 3626 if (done && *result) { 3627 rbd_assert(*result < 0); 3628 rbd_warn(rbd_dev, "%s%s result %d", 3629 test_bit(IMG_REQ_CHILD, &img_req->flags) ? "child " : "", 3630 obj_op_name(img_req->op_type), *result); 3631 } 3632 return done; 3633 } 3634 3635 static void rbd_img_handle_request(struct rbd_img_request *img_req, int result) 3636 { 3637 again: 3638 if (!__rbd_img_handle_request(img_req, &result)) 3639 return; 3640 3641 if (test_bit(IMG_REQ_CHILD, &img_req->flags)) { 3642 struct rbd_obj_request *obj_req = img_req->obj_request; 3643 3644 rbd_img_request_destroy(img_req); 3645 if (__rbd_obj_handle_request(obj_req, &result)) { 3646 img_req = obj_req->img_request; 3647 goto again; 3648 } 3649 } else { 3650 struct request *rq = blk_mq_rq_from_pdu(img_req); 3651 3652 rbd_img_request_destroy(img_req); 3653 blk_mq_end_request(rq, errno_to_blk_status(result)); 3654 } 3655 } 3656 3657 static const struct rbd_client_id rbd_empty_cid; 3658 3659 static bool rbd_cid_equal(const struct rbd_client_id *lhs, 3660 const struct rbd_client_id *rhs) 3661 { 3662 return lhs->gid == rhs->gid && lhs->handle == rhs->handle; 3663 } 3664 3665 static struct rbd_client_id rbd_get_cid(struct rbd_device *rbd_dev) 3666 { 3667 struct rbd_client_id cid; 3668 3669 mutex_lock(&rbd_dev->watch_mutex); 3670 cid.gid = ceph_client_gid(rbd_dev->rbd_client->client); 3671 cid.handle = rbd_dev->watch_cookie; 3672 mutex_unlock(&rbd_dev->watch_mutex); 3673 return cid; 3674 } 3675 3676 /* 3677 * lock_rwsem must be held for write 3678 */ 3679 static void rbd_set_owner_cid(struct rbd_device *rbd_dev, 3680 const struct rbd_client_id *cid) 3681 { 3682 dout("%s rbd_dev %p %llu-%llu -> %llu-%llu\n", __func__, rbd_dev, 3683 rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle, 3684 cid->gid, cid->handle); 3685 rbd_dev->owner_cid = *cid; /* struct */ 3686 } 3687 3688 static void format_lock_cookie(struct rbd_device *rbd_dev, char *buf) 3689 { 3690 mutex_lock(&rbd_dev->watch_mutex); 3691 sprintf(buf, "%s %llu", RBD_LOCK_COOKIE_PREFIX, rbd_dev->watch_cookie); 3692 mutex_unlock(&rbd_dev->watch_mutex); 3693 } 3694 3695 static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie) 3696 { 3697 struct rbd_client_id cid = rbd_get_cid(rbd_dev); 3698 3699 rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED; 3700 strcpy(rbd_dev->lock_cookie, cookie); 3701 rbd_set_owner_cid(rbd_dev, &cid); 3702 queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work); 3703 } 3704 3705 /* 3706 * lock_rwsem must be held for write 3707 */ 3708 static int rbd_lock(struct rbd_device *rbd_dev) 3709 { 3710 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3711 char cookie[32]; 3712 int ret; 3713 3714 WARN_ON(__rbd_is_lock_owner(rbd_dev) || 3715 rbd_dev->lock_cookie[0] != '\0'); 3716 3717 format_lock_cookie(rbd_dev, cookie); 3718 ret = ceph_cls_lock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 3719 RBD_LOCK_NAME, CEPH_CLS_LOCK_EXCLUSIVE, cookie, 3720 RBD_LOCK_TAG, "", 0); 3721 if (ret) 3722 return ret; 3723 3724 __rbd_lock(rbd_dev, cookie); 3725 return 0; 3726 } 3727 3728 /* 3729 * lock_rwsem must be held for write 3730 */ 3731 static void rbd_unlock(struct rbd_device *rbd_dev) 3732 { 3733 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3734 int ret; 3735 3736 WARN_ON(!__rbd_is_lock_owner(rbd_dev) || 3737 rbd_dev->lock_cookie[0] == '\0'); 3738 3739 ret = ceph_cls_unlock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 3740 RBD_LOCK_NAME, rbd_dev->lock_cookie); 3741 if (ret && ret != -ENOENT) 3742 rbd_warn(rbd_dev, "failed to unlock header: %d", ret); 3743 3744 /* treat errors as the image is unlocked */ 3745 rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED; 3746 rbd_dev->lock_cookie[0] = '\0'; 3747 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid); 3748 queue_work(rbd_dev->task_wq, &rbd_dev->released_lock_work); 3749 } 3750 3751 static int __rbd_notify_op_lock(struct rbd_device *rbd_dev, 3752 enum rbd_notify_op notify_op, 3753 struct page ***preply_pages, 3754 size_t *preply_len) 3755 { 3756 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3757 struct rbd_client_id cid = rbd_get_cid(rbd_dev); 3758 char buf[4 + 8 + 8 + CEPH_ENCODING_START_BLK_LEN]; 3759 int buf_size = sizeof(buf); 3760 void *p = buf; 3761 3762 dout("%s rbd_dev %p notify_op %d\n", __func__, rbd_dev, notify_op); 3763 3764 /* encode *LockPayload NotifyMessage (op + ClientId) */ 3765 ceph_start_encoding(&p, 2, 1, buf_size - CEPH_ENCODING_START_BLK_LEN); 3766 ceph_encode_32(&p, notify_op); 3767 ceph_encode_64(&p, cid.gid); 3768 ceph_encode_64(&p, cid.handle); 3769 3770 return ceph_osdc_notify(osdc, &rbd_dev->header_oid, 3771 &rbd_dev->header_oloc, buf, buf_size, 3772 RBD_NOTIFY_TIMEOUT, preply_pages, preply_len); 3773 } 3774 3775 static void rbd_notify_op_lock(struct rbd_device *rbd_dev, 3776 enum rbd_notify_op notify_op) 3777 { 3778 __rbd_notify_op_lock(rbd_dev, notify_op, NULL, NULL); 3779 } 3780 3781 static void rbd_notify_acquired_lock(struct work_struct *work) 3782 { 3783 struct rbd_device *rbd_dev = container_of(work, struct rbd_device, 3784 acquired_lock_work); 3785 3786 rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_ACQUIRED_LOCK); 3787 } 3788 3789 static void rbd_notify_released_lock(struct work_struct *work) 3790 { 3791 struct rbd_device *rbd_dev = container_of(work, struct rbd_device, 3792 released_lock_work); 3793 3794 rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_RELEASED_LOCK); 3795 } 3796 3797 static int rbd_request_lock(struct rbd_device *rbd_dev) 3798 { 3799 struct page **reply_pages; 3800 size_t reply_len; 3801 bool lock_owner_responded = false; 3802 int ret; 3803 3804 dout("%s rbd_dev %p\n", __func__, rbd_dev); 3805 3806 ret = __rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_REQUEST_LOCK, 3807 &reply_pages, &reply_len); 3808 if (ret && ret != -ETIMEDOUT) { 3809 rbd_warn(rbd_dev, "failed to request lock: %d", ret); 3810 goto out; 3811 } 3812 3813 if (reply_len > 0 && reply_len <= PAGE_SIZE) { 3814 void *p = page_address(reply_pages[0]); 3815 void *const end = p + reply_len; 3816 u32 n; 3817 3818 ceph_decode_32_safe(&p, end, n, e_inval); /* num_acks */ 3819 while (n--) { 3820 u8 struct_v; 3821 u32 len; 3822 3823 ceph_decode_need(&p, end, 8 + 8, e_inval); 3824 p += 8 + 8; /* skip gid and cookie */ 3825 3826 ceph_decode_32_safe(&p, end, len, e_inval); 3827 if (!len) 3828 continue; 3829 3830 if (lock_owner_responded) { 3831 rbd_warn(rbd_dev, 3832 "duplicate lock owners detected"); 3833 ret = -EIO; 3834 goto out; 3835 } 3836 3837 lock_owner_responded = true; 3838 ret = ceph_start_decoding(&p, end, 1, "ResponseMessage", 3839 &struct_v, &len); 3840 if (ret) { 3841 rbd_warn(rbd_dev, 3842 "failed to decode ResponseMessage: %d", 3843 ret); 3844 goto e_inval; 3845 } 3846 3847 ret = ceph_decode_32(&p); 3848 } 3849 } 3850 3851 if (!lock_owner_responded) { 3852 rbd_warn(rbd_dev, "no lock owners detected"); 3853 ret = -ETIMEDOUT; 3854 } 3855 3856 out: 3857 ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len)); 3858 return ret; 3859 3860 e_inval: 3861 ret = -EINVAL; 3862 goto out; 3863 } 3864 3865 /* 3866 * Either image request state machine(s) or rbd_add_acquire_lock() 3867 * (i.e. "rbd map"). 3868 */ 3869 static void wake_lock_waiters(struct rbd_device *rbd_dev, int result) 3870 { 3871 struct rbd_img_request *img_req; 3872 3873 dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result); 3874 lockdep_assert_held_write(&rbd_dev->lock_rwsem); 3875 3876 cancel_delayed_work(&rbd_dev->lock_dwork); 3877 if (!completion_done(&rbd_dev->acquire_wait)) { 3878 rbd_assert(list_empty(&rbd_dev->acquiring_list) && 3879 list_empty(&rbd_dev->running_list)); 3880 rbd_dev->acquire_err = result; 3881 complete_all(&rbd_dev->acquire_wait); 3882 return; 3883 } 3884 3885 list_for_each_entry(img_req, &rbd_dev->acquiring_list, lock_item) { 3886 mutex_lock(&img_req->state_mutex); 3887 rbd_assert(img_req->state == RBD_IMG_EXCLUSIVE_LOCK); 3888 rbd_img_schedule(img_req, result); 3889 mutex_unlock(&img_req->state_mutex); 3890 } 3891 3892 list_splice_tail_init(&rbd_dev->acquiring_list, &rbd_dev->running_list); 3893 } 3894 3895 static int get_lock_owner_info(struct rbd_device *rbd_dev, 3896 struct ceph_locker **lockers, u32 *num_lockers) 3897 { 3898 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3899 u8 lock_type; 3900 char *lock_tag; 3901 int ret; 3902 3903 dout("%s rbd_dev %p\n", __func__, rbd_dev); 3904 3905 ret = ceph_cls_lock_info(osdc, &rbd_dev->header_oid, 3906 &rbd_dev->header_oloc, RBD_LOCK_NAME, 3907 &lock_type, &lock_tag, lockers, num_lockers); 3908 if (ret) 3909 return ret; 3910 3911 if (*num_lockers == 0) { 3912 dout("%s rbd_dev %p no lockers detected\n", __func__, rbd_dev); 3913 goto out; 3914 } 3915 3916 if (strcmp(lock_tag, RBD_LOCK_TAG)) { 3917 rbd_warn(rbd_dev, "locked by external mechanism, tag %s", 3918 lock_tag); 3919 ret = -EBUSY; 3920 goto out; 3921 } 3922 3923 if (lock_type == CEPH_CLS_LOCK_SHARED) { 3924 rbd_warn(rbd_dev, "shared lock type detected"); 3925 ret = -EBUSY; 3926 goto out; 3927 } 3928 3929 if (strncmp((*lockers)[0].id.cookie, RBD_LOCK_COOKIE_PREFIX, 3930 strlen(RBD_LOCK_COOKIE_PREFIX))) { 3931 rbd_warn(rbd_dev, "locked by external mechanism, cookie %s", 3932 (*lockers)[0].id.cookie); 3933 ret = -EBUSY; 3934 goto out; 3935 } 3936 3937 out: 3938 kfree(lock_tag); 3939 return ret; 3940 } 3941 3942 static int find_watcher(struct rbd_device *rbd_dev, 3943 const struct ceph_locker *locker) 3944 { 3945 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3946 struct ceph_watch_item *watchers; 3947 u32 num_watchers; 3948 u64 cookie; 3949 int i; 3950 int ret; 3951 3952 ret = ceph_osdc_list_watchers(osdc, &rbd_dev->header_oid, 3953 &rbd_dev->header_oloc, &watchers, 3954 &num_watchers); 3955 if (ret) 3956 return ret; 3957 3958 sscanf(locker->id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu", &cookie); 3959 for (i = 0; i < num_watchers; i++) { 3960 if (!memcmp(&watchers[i].addr, &locker->info.addr, 3961 sizeof(locker->info.addr)) && 3962 watchers[i].cookie == cookie) { 3963 struct rbd_client_id cid = { 3964 .gid = le64_to_cpu(watchers[i].name.num), 3965 .handle = cookie, 3966 }; 3967 3968 dout("%s rbd_dev %p found cid %llu-%llu\n", __func__, 3969 rbd_dev, cid.gid, cid.handle); 3970 rbd_set_owner_cid(rbd_dev, &cid); 3971 ret = 1; 3972 goto out; 3973 } 3974 } 3975 3976 dout("%s rbd_dev %p no watchers\n", __func__, rbd_dev); 3977 ret = 0; 3978 out: 3979 kfree(watchers); 3980 return ret; 3981 } 3982 3983 /* 3984 * lock_rwsem must be held for write 3985 */ 3986 static int rbd_try_lock(struct rbd_device *rbd_dev) 3987 { 3988 struct ceph_client *client = rbd_dev->rbd_client->client; 3989 struct ceph_locker *lockers; 3990 u32 num_lockers; 3991 int ret; 3992 3993 for (;;) { 3994 ret = rbd_lock(rbd_dev); 3995 if (ret != -EBUSY) 3996 return ret; 3997 3998 /* determine if the current lock holder is still alive */ 3999 ret = get_lock_owner_info(rbd_dev, &lockers, &num_lockers); 4000 if (ret) 4001 return ret; 4002 4003 if (num_lockers == 0) 4004 goto again; 4005 4006 ret = find_watcher(rbd_dev, lockers); 4007 if (ret) 4008 goto out; /* request lock or error */ 4009 4010 rbd_warn(rbd_dev, "breaking header lock owned by %s%llu", 4011 ENTITY_NAME(lockers[0].id.name)); 4012 4013 ret = ceph_monc_blacklist_add(&client->monc, 4014 &lockers[0].info.addr); 4015 if (ret) { 4016 rbd_warn(rbd_dev, "blacklist of %s%llu failed: %d", 4017 ENTITY_NAME(lockers[0].id.name), ret); 4018 goto out; 4019 } 4020 4021 ret = ceph_cls_break_lock(&client->osdc, &rbd_dev->header_oid, 4022 &rbd_dev->header_oloc, RBD_LOCK_NAME, 4023 lockers[0].id.cookie, 4024 &lockers[0].id.name); 4025 if (ret && ret != -ENOENT) 4026 goto out; 4027 4028 again: 4029 ceph_free_lockers(lockers, num_lockers); 4030 } 4031 4032 out: 4033 ceph_free_lockers(lockers, num_lockers); 4034 return ret; 4035 } 4036 4037 static int rbd_post_acquire_action(struct rbd_device *rbd_dev) 4038 { 4039 int ret; 4040 4041 if (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) { 4042 ret = rbd_object_map_open(rbd_dev); 4043 if (ret) 4044 return ret; 4045 } 4046 4047 return 0; 4048 } 4049 4050 /* 4051 * Return: 4052 * 0 - lock acquired 4053 * 1 - caller should call rbd_request_lock() 4054 * <0 - error 4055 */ 4056 static int rbd_try_acquire_lock(struct rbd_device *rbd_dev) 4057 { 4058 int ret; 4059 4060 down_read(&rbd_dev->lock_rwsem); 4061 dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev, 4062 rbd_dev->lock_state); 4063 if (__rbd_is_lock_owner(rbd_dev)) { 4064 up_read(&rbd_dev->lock_rwsem); 4065 return 0; 4066 } 4067 4068 up_read(&rbd_dev->lock_rwsem); 4069 down_write(&rbd_dev->lock_rwsem); 4070 dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev, 4071 rbd_dev->lock_state); 4072 if (__rbd_is_lock_owner(rbd_dev)) { 4073 up_write(&rbd_dev->lock_rwsem); 4074 return 0; 4075 } 4076 4077 ret = rbd_try_lock(rbd_dev); 4078 if (ret < 0) { 4079 rbd_warn(rbd_dev, "failed to lock header: %d", ret); 4080 if (ret == -EBLACKLISTED) 4081 goto out; 4082 4083 ret = 1; /* request lock anyway */ 4084 } 4085 if (ret > 0) { 4086 up_write(&rbd_dev->lock_rwsem); 4087 return ret; 4088 } 4089 4090 rbd_assert(rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED); 4091 rbd_assert(list_empty(&rbd_dev->running_list)); 4092 4093 ret = rbd_post_acquire_action(rbd_dev); 4094 if (ret) { 4095 rbd_warn(rbd_dev, "post-acquire action failed: %d", ret); 4096 /* 4097 * Can't stay in RBD_LOCK_STATE_LOCKED because 4098 * rbd_lock_add_request() would let the request through, 4099 * assuming that e.g. object map is locked and loaded. 4100 */ 4101 rbd_unlock(rbd_dev); 4102 } 4103 4104 out: 4105 wake_lock_waiters(rbd_dev, ret); 4106 up_write(&rbd_dev->lock_rwsem); 4107 return ret; 4108 } 4109 4110 static void rbd_acquire_lock(struct work_struct *work) 4111 { 4112 struct rbd_device *rbd_dev = container_of(to_delayed_work(work), 4113 struct rbd_device, lock_dwork); 4114 int ret; 4115 4116 dout("%s rbd_dev %p\n", __func__, rbd_dev); 4117 again: 4118 ret = rbd_try_acquire_lock(rbd_dev); 4119 if (ret <= 0) { 4120 dout("%s rbd_dev %p ret %d - done\n", __func__, rbd_dev, ret); 4121 return; 4122 } 4123 4124 ret = rbd_request_lock(rbd_dev); 4125 if (ret == -ETIMEDOUT) { 4126 goto again; /* treat this as a dead client */ 4127 } else if (ret == -EROFS) { 4128 rbd_warn(rbd_dev, "peer will not release lock"); 4129 down_write(&rbd_dev->lock_rwsem); 4130 wake_lock_waiters(rbd_dev, ret); 4131 up_write(&rbd_dev->lock_rwsem); 4132 } else if (ret < 0) { 4133 rbd_warn(rbd_dev, "error requesting lock: %d", ret); 4134 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 4135 RBD_RETRY_DELAY); 4136 } else { 4137 /* 4138 * lock owner acked, but resend if we don't see them 4139 * release the lock 4140 */ 4141 dout("%s rbd_dev %p requeuing lock_dwork\n", __func__, 4142 rbd_dev); 4143 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 4144 msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC)); 4145 } 4146 } 4147 4148 static bool rbd_quiesce_lock(struct rbd_device *rbd_dev) 4149 { 4150 bool need_wait; 4151 4152 dout("%s rbd_dev %p\n", __func__, rbd_dev); 4153 lockdep_assert_held_write(&rbd_dev->lock_rwsem); 4154 4155 if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED) 4156 return false; 4157 4158 /* 4159 * Ensure that all in-flight IO is flushed. 4160 */ 4161 rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING; 4162 rbd_assert(!completion_done(&rbd_dev->releasing_wait)); 4163 need_wait = !list_empty(&rbd_dev->running_list); 4164 downgrade_write(&rbd_dev->lock_rwsem); 4165 if (need_wait) 4166 wait_for_completion(&rbd_dev->releasing_wait); 4167 up_read(&rbd_dev->lock_rwsem); 4168 4169 down_write(&rbd_dev->lock_rwsem); 4170 if (rbd_dev->lock_state != RBD_LOCK_STATE_RELEASING) 4171 return false; 4172 4173 rbd_assert(list_empty(&rbd_dev->running_list)); 4174 return true; 4175 } 4176 4177 static void rbd_pre_release_action(struct rbd_device *rbd_dev) 4178 { 4179 if (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) 4180 rbd_object_map_close(rbd_dev); 4181 } 4182 4183 static void __rbd_release_lock(struct rbd_device *rbd_dev) 4184 { 4185 rbd_assert(list_empty(&rbd_dev->running_list)); 4186 4187 rbd_pre_release_action(rbd_dev); 4188 rbd_unlock(rbd_dev); 4189 } 4190 4191 /* 4192 * lock_rwsem must be held for write 4193 */ 4194 static void rbd_release_lock(struct rbd_device *rbd_dev) 4195 { 4196 if (!rbd_quiesce_lock(rbd_dev)) 4197 return; 4198 4199 __rbd_release_lock(rbd_dev); 4200 4201 /* 4202 * Give others a chance to grab the lock - we would re-acquire 4203 * almost immediately if we got new IO while draining the running 4204 * list otherwise. We need to ack our own notifications, so this 4205 * lock_dwork will be requeued from rbd_handle_released_lock() by 4206 * way of maybe_kick_acquire(). 4207 */ 4208 cancel_delayed_work(&rbd_dev->lock_dwork); 4209 } 4210 4211 static void rbd_release_lock_work(struct work_struct *work) 4212 { 4213 struct rbd_device *rbd_dev = container_of(work, struct rbd_device, 4214 unlock_work); 4215 4216 down_write(&rbd_dev->lock_rwsem); 4217 rbd_release_lock(rbd_dev); 4218 up_write(&rbd_dev->lock_rwsem); 4219 } 4220 4221 static void maybe_kick_acquire(struct rbd_device *rbd_dev) 4222 { 4223 bool have_requests; 4224 4225 dout("%s rbd_dev %p\n", __func__, rbd_dev); 4226 if (__rbd_is_lock_owner(rbd_dev)) 4227 return; 4228 4229 spin_lock(&rbd_dev->lock_lists_lock); 4230 have_requests = !list_empty(&rbd_dev->acquiring_list); 4231 spin_unlock(&rbd_dev->lock_lists_lock); 4232 if (have_requests || delayed_work_pending(&rbd_dev->lock_dwork)) { 4233 dout("%s rbd_dev %p kicking lock_dwork\n", __func__, rbd_dev); 4234 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0); 4235 } 4236 } 4237 4238 static void rbd_handle_acquired_lock(struct rbd_device *rbd_dev, u8 struct_v, 4239 void **p) 4240 { 4241 struct rbd_client_id cid = { 0 }; 4242 4243 if (struct_v >= 2) { 4244 cid.gid = ceph_decode_64(p); 4245 cid.handle = ceph_decode_64(p); 4246 } 4247 4248 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid, 4249 cid.handle); 4250 if (!rbd_cid_equal(&cid, &rbd_empty_cid)) { 4251 down_write(&rbd_dev->lock_rwsem); 4252 if (rbd_cid_equal(&cid, &rbd_dev->owner_cid)) { 4253 /* 4254 * we already know that the remote client is 4255 * the owner 4256 */ 4257 up_write(&rbd_dev->lock_rwsem); 4258 return; 4259 } 4260 4261 rbd_set_owner_cid(rbd_dev, &cid); 4262 downgrade_write(&rbd_dev->lock_rwsem); 4263 } else { 4264 down_read(&rbd_dev->lock_rwsem); 4265 } 4266 4267 maybe_kick_acquire(rbd_dev); 4268 up_read(&rbd_dev->lock_rwsem); 4269 } 4270 4271 static void rbd_handle_released_lock(struct rbd_device *rbd_dev, u8 struct_v, 4272 void **p) 4273 { 4274 struct rbd_client_id cid = { 0 }; 4275 4276 if (struct_v >= 2) { 4277 cid.gid = ceph_decode_64(p); 4278 cid.handle = ceph_decode_64(p); 4279 } 4280 4281 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid, 4282 cid.handle); 4283 if (!rbd_cid_equal(&cid, &rbd_empty_cid)) { 4284 down_write(&rbd_dev->lock_rwsem); 4285 if (!rbd_cid_equal(&cid, &rbd_dev->owner_cid)) { 4286 dout("%s rbd_dev %p unexpected owner, cid %llu-%llu != owner_cid %llu-%llu\n", 4287 __func__, rbd_dev, cid.gid, cid.handle, 4288 rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle); 4289 up_write(&rbd_dev->lock_rwsem); 4290 return; 4291 } 4292 4293 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid); 4294 downgrade_write(&rbd_dev->lock_rwsem); 4295 } else { 4296 down_read(&rbd_dev->lock_rwsem); 4297 } 4298 4299 maybe_kick_acquire(rbd_dev); 4300 up_read(&rbd_dev->lock_rwsem); 4301 } 4302 4303 /* 4304 * Returns result for ResponseMessage to be encoded (<= 0), or 1 if no 4305 * ResponseMessage is needed. 4306 */ 4307 static int rbd_handle_request_lock(struct rbd_device *rbd_dev, u8 struct_v, 4308 void **p) 4309 { 4310 struct rbd_client_id my_cid = rbd_get_cid(rbd_dev); 4311 struct rbd_client_id cid = { 0 }; 4312 int result = 1; 4313 4314 if (struct_v >= 2) { 4315 cid.gid = ceph_decode_64(p); 4316 cid.handle = ceph_decode_64(p); 4317 } 4318 4319 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid, 4320 cid.handle); 4321 if (rbd_cid_equal(&cid, &my_cid)) 4322 return result; 4323 4324 down_read(&rbd_dev->lock_rwsem); 4325 if (__rbd_is_lock_owner(rbd_dev)) { 4326 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED && 4327 rbd_cid_equal(&rbd_dev->owner_cid, &rbd_empty_cid)) 4328 goto out_unlock; 4329 4330 /* 4331 * encode ResponseMessage(0) so the peer can detect 4332 * a missing owner 4333 */ 4334 result = 0; 4335 4336 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) { 4337 if (!rbd_dev->opts->exclusive) { 4338 dout("%s rbd_dev %p queueing unlock_work\n", 4339 __func__, rbd_dev); 4340 queue_work(rbd_dev->task_wq, 4341 &rbd_dev->unlock_work); 4342 } else { 4343 /* refuse to release the lock */ 4344 result = -EROFS; 4345 } 4346 } 4347 } 4348 4349 out_unlock: 4350 up_read(&rbd_dev->lock_rwsem); 4351 return result; 4352 } 4353 4354 static void __rbd_acknowledge_notify(struct rbd_device *rbd_dev, 4355 u64 notify_id, u64 cookie, s32 *result) 4356 { 4357 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4358 char buf[4 + CEPH_ENCODING_START_BLK_LEN]; 4359 int buf_size = sizeof(buf); 4360 int ret; 4361 4362 if (result) { 4363 void *p = buf; 4364 4365 /* encode ResponseMessage */ 4366 ceph_start_encoding(&p, 1, 1, 4367 buf_size - CEPH_ENCODING_START_BLK_LEN); 4368 ceph_encode_32(&p, *result); 4369 } else { 4370 buf_size = 0; 4371 } 4372 4373 ret = ceph_osdc_notify_ack(osdc, &rbd_dev->header_oid, 4374 &rbd_dev->header_oloc, notify_id, cookie, 4375 buf, buf_size); 4376 if (ret) 4377 rbd_warn(rbd_dev, "acknowledge_notify failed: %d", ret); 4378 } 4379 4380 static void rbd_acknowledge_notify(struct rbd_device *rbd_dev, u64 notify_id, 4381 u64 cookie) 4382 { 4383 dout("%s rbd_dev %p\n", __func__, rbd_dev); 4384 __rbd_acknowledge_notify(rbd_dev, notify_id, cookie, NULL); 4385 } 4386 4387 static void rbd_acknowledge_notify_result(struct rbd_device *rbd_dev, 4388 u64 notify_id, u64 cookie, s32 result) 4389 { 4390 dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result); 4391 __rbd_acknowledge_notify(rbd_dev, notify_id, cookie, &result); 4392 } 4393 4394 static void rbd_watch_cb(void *arg, u64 notify_id, u64 cookie, 4395 u64 notifier_id, void *data, size_t data_len) 4396 { 4397 struct rbd_device *rbd_dev = arg; 4398 void *p = data; 4399 void *const end = p + data_len; 4400 u8 struct_v = 0; 4401 u32 len; 4402 u32 notify_op; 4403 int ret; 4404 4405 dout("%s rbd_dev %p cookie %llu notify_id %llu data_len %zu\n", 4406 __func__, rbd_dev, cookie, notify_id, data_len); 4407 if (data_len) { 4408 ret = ceph_start_decoding(&p, end, 1, "NotifyMessage", 4409 &struct_v, &len); 4410 if (ret) { 4411 rbd_warn(rbd_dev, "failed to decode NotifyMessage: %d", 4412 ret); 4413 return; 4414 } 4415 4416 notify_op = ceph_decode_32(&p); 4417 } else { 4418 /* legacy notification for header updates */ 4419 notify_op = RBD_NOTIFY_OP_HEADER_UPDATE; 4420 len = 0; 4421 } 4422 4423 dout("%s rbd_dev %p notify_op %u\n", __func__, rbd_dev, notify_op); 4424 switch (notify_op) { 4425 case RBD_NOTIFY_OP_ACQUIRED_LOCK: 4426 rbd_handle_acquired_lock(rbd_dev, struct_v, &p); 4427 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 4428 break; 4429 case RBD_NOTIFY_OP_RELEASED_LOCK: 4430 rbd_handle_released_lock(rbd_dev, struct_v, &p); 4431 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 4432 break; 4433 case RBD_NOTIFY_OP_REQUEST_LOCK: 4434 ret = rbd_handle_request_lock(rbd_dev, struct_v, &p); 4435 if (ret <= 0) 4436 rbd_acknowledge_notify_result(rbd_dev, notify_id, 4437 cookie, ret); 4438 else 4439 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 4440 break; 4441 case RBD_NOTIFY_OP_HEADER_UPDATE: 4442 ret = rbd_dev_refresh(rbd_dev); 4443 if (ret) 4444 rbd_warn(rbd_dev, "refresh failed: %d", ret); 4445 4446 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 4447 break; 4448 default: 4449 if (rbd_is_lock_owner(rbd_dev)) 4450 rbd_acknowledge_notify_result(rbd_dev, notify_id, 4451 cookie, -EOPNOTSUPP); 4452 else 4453 rbd_acknowledge_notify(rbd_dev, notify_id, cookie); 4454 break; 4455 } 4456 } 4457 4458 static void __rbd_unregister_watch(struct rbd_device *rbd_dev); 4459 4460 static void rbd_watch_errcb(void *arg, u64 cookie, int err) 4461 { 4462 struct rbd_device *rbd_dev = arg; 4463 4464 rbd_warn(rbd_dev, "encountered watch error: %d", err); 4465 4466 down_write(&rbd_dev->lock_rwsem); 4467 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid); 4468 up_write(&rbd_dev->lock_rwsem); 4469 4470 mutex_lock(&rbd_dev->watch_mutex); 4471 if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) { 4472 __rbd_unregister_watch(rbd_dev); 4473 rbd_dev->watch_state = RBD_WATCH_STATE_ERROR; 4474 4475 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->watch_dwork, 0); 4476 } 4477 mutex_unlock(&rbd_dev->watch_mutex); 4478 } 4479 4480 /* 4481 * watch_mutex must be locked 4482 */ 4483 static int __rbd_register_watch(struct rbd_device *rbd_dev) 4484 { 4485 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4486 struct ceph_osd_linger_request *handle; 4487 4488 rbd_assert(!rbd_dev->watch_handle); 4489 dout("%s rbd_dev %p\n", __func__, rbd_dev); 4490 4491 handle = ceph_osdc_watch(osdc, &rbd_dev->header_oid, 4492 &rbd_dev->header_oloc, rbd_watch_cb, 4493 rbd_watch_errcb, rbd_dev); 4494 if (IS_ERR(handle)) 4495 return PTR_ERR(handle); 4496 4497 rbd_dev->watch_handle = handle; 4498 return 0; 4499 } 4500 4501 /* 4502 * watch_mutex must be locked 4503 */ 4504 static void __rbd_unregister_watch(struct rbd_device *rbd_dev) 4505 { 4506 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4507 int ret; 4508 4509 rbd_assert(rbd_dev->watch_handle); 4510 dout("%s rbd_dev %p\n", __func__, rbd_dev); 4511 4512 ret = ceph_osdc_unwatch(osdc, rbd_dev->watch_handle); 4513 if (ret) 4514 rbd_warn(rbd_dev, "failed to unwatch: %d", ret); 4515 4516 rbd_dev->watch_handle = NULL; 4517 } 4518 4519 static int rbd_register_watch(struct rbd_device *rbd_dev) 4520 { 4521 int ret; 4522 4523 mutex_lock(&rbd_dev->watch_mutex); 4524 rbd_assert(rbd_dev->watch_state == RBD_WATCH_STATE_UNREGISTERED); 4525 ret = __rbd_register_watch(rbd_dev); 4526 if (ret) 4527 goto out; 4528 4529 rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED; 4530 rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id; 4531 4532 out: 4533 mutex_unlock(&rbd_dev->watch_mutex); 4534 return ret; 4535 } 4536 4537 static void cancel_tasks_sync(struct rbd_device *rbd_dev) 4538 { 4539 dout("%s rbd_dev %p\n", __func__, rbd_dev); 4540 4541 cancel_work_sync(&rbd_dev->acquired_lock_work); 4542 cancel_work_sync(&rbd_dev->released_lock_work); 4543 cancel_delayed_work_sync(&rbd_dev->lock_dwork); 4544 cancel_work_sync(&rbd_dev->unlock_work); 4545 } 4546 4547 /* 4548 * header_rwsem must not be held to avoid a deadlock with 4549 * rbd_dev_refresh() when flushing notifies. 4550 */ 4551 static void rbd_unregister_watch(struct rbd_device *rbd_dev) 4552 { 4553 cancel_tasks_sync(rbd_dev); 4554 4555 mutex_lock(&rbd_dev->watch_mutex); 4556 if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) 4557 __rbd_unregister_watch(rbd_dev); 4558 rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED; 4559 mutex_unlock(&rbd_dev->watch_mutex); 4560 4561 cancel_delayed_work_sync(&rbd_dev->watch_dwork); 4562 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc); 4563 } 4564 4565 /* 4566 * lock_rwsem must be held for write 4567 */ 4568 static void rbd_reacquire_lock(struct rbd_device *rbd_dev) 4569 { 4570 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4571 char cookie[32]; 4572 int ret; 4573 4574 if (!rbd_quiesce_lock(rbd_dev)) 4575 return; 4576 4577 format_lock_cookie(rbd_dev, cookie); 4578 ret = ceph_cls_set_cookie(osdc, &rbd_dev->header_oid, 4579 &rbd_dev->header_oloc, RBD_LOCK_NAME, 4580 CEPH_CLS_LOCK_EXCLUSIVE, rbd_dev->lock_cookie, 4581 RBD_LOCK_TAG, cookie); 4582 if (ret) { 4583 if (ret != -EOPNOTSUPP) 4584 rbd_warn(rbd_dev, "failed to update lock cookie: %d", 4585 ret); 4586 4587 /* 4588 * Lock cookie cannot be updated on older OSDs, so do 4589 * a manual release and queue an acquire. 4590 */ 4591 __rbd_release_lock(rbd_dev); 4592 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0); 4593 } else { 4594 __rbd_lock(rbd_dev, cookie); 4595 wake_lock_waiters(rbd_dev, 0); 4596 } 4597 } 4598 4599 static void rbd_reregister_watch(struct work_struct *work) 4600 { 4601 struct rbd_device *rbd_dev = container_of(to_delayed_work(work), 4602 struct rbd_device, watch_dwork); 4603 int ret; 4604 4605 dout("%s rbd_dev %p\n", __func__, rbd_dev); 4606 4607 mutex_lock(&rbd_dev->watch_mutex); 4608 if (rbd_dev->watch_state != RBD_WATCH_STATE_ERROR) { 4609 mutex_unlock(&rbd_dev->watch_mutex); 4610 return; 4611 } 4612 4613 ret = __rbd_register_watch(rbd_dev); 4614 if (ret) { 4615 rbd_warn(rbd_dev, "failed to reregister watch: %d", ret); 4616 if (ret != -EBLACKLISTED && ret != -ENOENT) { 4617 queue_delayed_work(rbd_dev->task_wq, 4618 &rbd_dev->watch_dwork, 4619 RBD_RETRY_DELAY); 4620 mutex_unlock(&rbd_dev->watch_mutex); 4621 return; 4622 } 4623 4624 mutex_unlock(&rbd_dev->watch_mutex); 4625 down_write(&rbd_dev->lock_rwsem); 4626 wake_lock_waiters(rbd_dev, ret); 4627 up_write(&rbd_dev->lock_rwsem); 4628 return; 4629 } 4630 4631 rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED; 4632 rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id; 4633 mutex_unlock(&rbd_dev->watch_mutex); 4634 4635 down_write(&rbd_dev->lock_rwsem); 4636 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) 4637 rbd_reacquire_lock(rbd_dev); 4638 up_write(&rbd_dev->lock_rwsem); 4639 4640 ret = rbd_dev_refresh(rbd_dev); 4641 if (ret) 4642 rbd_warn(rbd_dev, "reregistration refresh failed: %d", ret); 4643 } 4644 4645 /* 4646 * Synchronous osd object method call. Returns the number of bytes 4647 * returned in the outbound buffer, or a negative error code. 4648 */ 4649 static int rbd_obj_method_sync(struct rbd_device *rbd_dev, 4650 struct ceph_object_id *oid, 4651 struct ceph_object_locator *oloc, 4652 const char *method_name, 4653 const void *outbound, 4654 size_t outbound_size, 4655 void *inbound, 4656 size_t inbound_size) 4657 { 4658 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4659 struct page *req_page = NULL; 4660 struct page *reply_page; 4661 int ret; 4662 4663 /* 4664 * Method calls are ultimately read operations. The result 4665 * should placed into the inbound buffer provided. They 4666 * also supply outbound data--parameters for the object 4667 * method. Currently if this is present it will be a 4668 * snapshot id. 4669 */ 4670 if (outbound) { 4671 if (outbound_size > PAGE_SIZE) 4672 return -E2BIG; 4673 4674 req_page = alloc_page(GFP_KERNEL); 4675 if (!req_page) 4676 return -ENOMEM; 4677 4678 memcpy(page_address(req_page), outbound, outbound_size); 4679 } 4680 4681 reply_page = alloc_page(GFP_KERNEL); 4682 if (!reply_page) { 4683 if (req_page) 4684 __free_page(req_page); 4685 return -ENOMEM; 4686 } 4687 4688 ret = ceph_osdc_call(osdc, oid, oloc, RBD_DRV_NAME, method_name, 4689 CEPH_OSD_FLAG_READ, req_page, outbound_size, 4690 &reply_page, &inbound_size); 4691 if (!ret) { 4692 memcpy(inbound, page_address(reply_page), inbound_size); 4693 ret = inbound_size; 4694 } 4695 4696 if (req_page) 4697 __free_page(req_page); 4698 __free_page(reply_page); 4699 return ret; 4700 } 4701 4702 static void rbd_queue_workfn(struct work_struct *work) 4703 { 4704 struct rbd_img_request *img_request = 4705 container_of(work, struct rbd_img_request, work); 4706 struct rbd_device *rbd_dev = img_request->rbd_dev; 4707 enum obj_operation_type op_type = img_request->op_type; 4708 struct request *rq = blk_mq_rq_from_pdu(img_request); 4709 u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT; 4710 u64 length = blk_rq_bytes(rq); 4711 u64 mapping_size; 4712 int result; 4713 4714 /* Ignore/skip any zero-length requests */ 4715 if (!length) { 4716 dout("%s: zero-length request\n", __func__); 4717 result = 0; 4718 goto err_img_request; 4719 } 4720 4721 blk_mq_start_request(rq); 4722 4723 down_read(&rbd_dev->header_rwsem); 4724 mapping_size = rbd_dev->mapping.size; 4725 rbd_img_capture_header(img_request); 4726 up_read(&rbd_dev->header_rwsem); 4727 4728 if (offset + length > mapping_size) { 4729 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)", offset, 4730 length, mapping_size); 4731 result = -EIO; 4732 goto err_img_request; 4733 } 4734 4735 dout("%s rbd_dev %p img_req %p %s %llu~%llu\n", __func__, rbd_dev, 4736 img_request, obj_op_name(op_type), offset, length); 4737 4738 if (op_type == OBJ_OP_DISCARD || op_type == OBJ_OP_ZEROOUT) 4739 result = rbd_img_fill_nodata(img_request, offset, length); 4740 else 4741 result = rbd_img_fill_from_bio(img_request, offset, length, 4742 rq->bio); 4743 if (result) 4744 goto err_img_request; 4745 4746 rbd_img_handle_request(img_request, 0); 4747 return; 4748 4749 err_img_request: 4750 rbd_img_request_destroy(img_request); 4751 if (result) 4752 rbd_warn(rbd_dev, "%s %llx at %llx result %d", 4753 obj_op_name(op_type), length, offset, result); 4754 blk_mq_end_request(rq, errno_to_blk_status(result)); 4755 } 4756 4757 static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx, 4758 const struct blk_mq_queue_data *bd) 4759 { 4760 struct rbd_device *rbd_dev = hctx->queue->queuedata; 4761 struct rbd_img_request *img_req = blk_mq_rq_to_pdu(bd->rq); 4762 enum obj_operation_type op_type; 4763 4764 switch (req_op(bd->rq)) { 4765 case REQ_OP_DISCARD: 4766 op_type = OBJ_OP_DISCARD; 4767 break; 4768 case REQ_OP_WRITE_ZEROES: 4769 op_type = OBJ_OP_ZEROOUT; 4770 break; 4771 case REQ_OP_WRITE: 4772 op_type = OBJ_OP_WRITE; 4773 break; 4774 case REQ_OP_READ: 4775 op_type = OBJ_OP_READ; 4776 break; 4777 default: 4778 rbd_warn(rbd_dev, "unknown req_op %d", req_op(bd->rq)); 4779 return BLK_STS_IOERR; 4780 } 4781 4782 rbd_img_request_init(img_req, rbd_dev, op_type); 4783 4784 if (rbd_img_is_write(img_req)) { 4785 if (rbd_is_ro(rbd_dev)) { 4786 rbd_warn(rbd_dev, "%s on read-only mapping", 4787 obj_op_name(img_req->op_type)); 4788 return BLK_STS_IOERR; 4789 } 4790 rbd_assert(!rbd_is_snap(rbd_dev)); 4791 } 4792 4793 INIT_WORK(&img_req->work, rbd_queue_workfn); 4794 queue_work(rbd_wq, &img_req->work); 4795 return BLK_STS_OK; 4796 } 4797 4798 static void rbd_free_disk(struct rbd_device *rbd_dev) 4799 { 4800 blk_cleanup_queue(rbd_dev->disk->queue); 4801 blk_mq_free_tag_set(&rbd_dev->tag_set); 4802 put_disk(rbd_dev->disk); 4803 rbd_dev->disk = NULL; 4804 } 4805 4806 static int rbd_obj_read_sync(struct rbd_device *rbd_dev, 4807 struct ceph_object_id *oid, 4808 struct ceph_object_locator *oloc, 4809 void *buf, int buf_len) 4810 4811 { 4812 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4813 struct ceph_osd_request *req; 4814 struct page **pages; 4815 int num_pages = calc_pages_for(0, buf_len); 4816 int ret; 4817 4818 req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL); 4819 if (!req) 4820 return -ENOMEM; 4821 4822 ceph_oid_copy(&req->r_base_oid, oid); 4823 ceph_oloc_copy(&req->r_base_oloc, oloc); 4824 req->r_flags = CEPH_OSD_FLAG_READ; 4825 4826 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL); 4827 if (IS_ERR(pages)) { 4828 ret = PTR_ERR(pages); 4829 goto out_req; 4830 } 4831 4832 osd_req_op_extent_init(req, 0, CEPH_OSD_OP_READ, 0, buf_len, 0, 0); 4833 osd_req_op_extent_osd_data_pages(req, 0, pages, buf_len, 0, false, 4834 true); 4835 4836 ret = ceph_osdc_alloc_messages(req, GFP_KERNEL); 4837 if (ret) 4838 goto out_req; 4839 4840 ceph_osdc_start_request(osdc, req, false); 4841 ret = ceph_osdc_wait_request(osdc, req); 4842 if (ret >= 0) 4843 ceph_copy_from_page_vector(pages, buf, 0, ret); 4844 4845 out_req: 4846 ceph_osdc_put_request(req); 4847 return ret; 4848 } 4849 4850 /* 4851 * Read the complete header for the given rbd device. On successful 4852 * return, the rbd_dev->header field will contain up-to-date 4853 * information about the image. 4854 */ 4855 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev) 4856 { 4857 struct rbd_image_header_ondisk *ondisk = NULL; 4858 u32 snap_count = 0; 4859 u64 names_size = 0; 4860 u32 want_count; 4861 int ret; 4862 4863 /* 4864 * The complete header will include an array of its 64-bit 4865 * snapshot ids, followed by the names of those snapshots as 4866 * a contiguous block of NUL-terminated strings. Note that 4867 * the number of snapshots could change by the time we read 4868 * it in, in which case we re-read it. 4869 */ 4870 do { 4871 size_t size; 4872 4873 kfree(ondisk); 4874 4875 size = sizeof (*ondisk); 4876 size += snap_count * sizeof (struct rbd_image_snap_ondisk); 4877 size += names_size; 4878 ondisk = kmalloc(size, GFP_KERNEL); 4879 if (!ondisk) 4880 return -ENOMEM; 4881 4882 ret = rbd_obj_read_sync(rbd_dev, &rbd_dev->header_oid, 4883 &rbd_dev->header_oloc, ondisk, size); 4884 if (ret < 0) 4885 goto out; 4886 if ((size_t)ret < size) { 4887 ret = -ENXIO; 4888 rbd_warn(rbd_dev, "short header read (want %zd got %d)", 4889 size, ret); 4890 goto out; 4891 } 4892 if (!rbd_dev_ondisk_valid(ondisk)) { 4893 ret = -ENXIO; 4894 rbd_warn(rbd_dev, "invalid header"); 4895 goto out; 4896 } 4897 4898 names_size = le64_to_cpu(ondisk->snap_names_len); 4899 want_count = snap_count; 4900 snap_count = le32_to_cpu(ondisk->snap_count); 4901 } while (snap_count != want_count); 4902 4903 ret = rbd_header_from_disk(rbd_dev, ondisk); 4904 out: 4905 kfree(ondisk); 4906 4907 return ret; 4908 } 4909 4910 static void rbd_dev_update_size(struct rbd_device *rbd_dev) 4911 { 4912 sector_t size; 4913 4914 /* 4915 * If EXISTS is not set, rbd_dev->disk may be NULL, so don't 4916 * try to update its size. If REMOVING is set, updating size 4917 * is just useless work since the device can't be opened. 4918 */ 4919 if (test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags) && 4920 !test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) { 4921 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE; 4922 dout("setting size to %llu sectors", (unsigned long long)size); 4923 set_capacity(rbd_dev->disk, size); 4924 revalidate_disk(rbd_dev->disk); 4925 } 4926 } 4927 4928 static int rbd_dev_refresh(struct rbd_device *rbd_dev) 4929 { 4930 u64 mapping_size; 4931 int ret; 4932 4933 down_write(&rbd_dev->header_rwsem); 4934 mapping_size = rbd_dev->mapping.size; 4935 4936 ret = rbd_dev_header_info(rbd_dev); 4937 if (ret) 4938 goto out; 4939 4940 /* 4941 * If there is a parent, see if it has disappeared due to the 4942 * mapped image getting flattened. 4943 */ 4944 if (rbd_dev->parent) { 4945 ret = rbd_dev_v2_parent_info(rbd_dev); 4946 if (ret) 4947 goto out; 4948 } 4949 4950 rbd_assert(!rbd_is_snap(rbd_dev)); 4951 rbd_dev->mapping.size = rbd_dev->header.image_size; 4952 4953 out: 4954 up_write(&rbd_dev->header_rwsem); 4955 if (!ret && mapping_size != rbd_dev->mapping.size) 4956 rbd_dev_update_size(rbd_dev); 4957 4958 return ret; 4959 } 4960 4961 static const struct blk_mq_ops rbd_mq_ops = { 4962 .queue_rq = rbd_queue_rq, 4963 }; 4964 4965 static int rbd_init_disk(struct rbd_device *rbd_dev) 4966 { 4967 struct gendisk *disk; 4968 struct request_queue *q; 4969 unsigned int objset_bytes = 4970 rbd_dev->layout.object_size * rbd_dev->layout.stripe_count; 4971 int err; 4972 4973 /* create gendisk info */ 4974 disk = alloc_disk(single_major ? 4975 (1 << RBD_SINGLE_MAJOR_PART_SHIFT) : 4976 RBD_MINORS_PER_MAJOR); 4977 if (!disk) 4978 return -ENOMEM; 4979 4980 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d", 4981 rbd_dev->dev_id); 4982 disk->major = rbd_dev->major; 4983 disk->first_minor = rbd_dev->minor; 4984 if (single_major) 4985 disk->flags |= GENHD_FL_EXT_DEVT; 4986 disk->fops = &rbd_bd_ops; 4987 disk->private_data = rbd_dev; 4988 4989 memset(&rbd_dev->tag_set, 0, sizeof(rbd_dev->tag_set)); 4990 rbd_dev->tag_set.ops = &rbd_mq_ops; 4991 rbd_dev->tag_set.queue_depth = rbd_dev->opts->queue_depth; 4992 rbd_dev->tag_set.numa_node = NUMA_NO_NODE; 4993 rbd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; 4994 rbd_dev->tag_set.nr_hw_queues = num_present_cpus(); 4995 rbd_dev->tag_set.cmd_size = sizeof(struct rbd_img_request); 4996 4997 err = blk_mq_alloc_tag_set(&rbd_dev->tag_set); 4998 if (err) 4999 goto out_disk; 5000 5001 q = blk_mq_init_queue(&rbd_dev->tag_set); 5002 if (IS_ERR(q)) { 5003 err = PTR_ERR(q); 5004 goto out_tag_set; 5005 } 5006 5007 blk_queue_flag_set(QUEUE_FLAG_NONROT, q); 5008 /* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */ 5009 5010 blk_queue_max_hw_sectors(q, objset_bytes >> SECTOR_SHIFT); 5011 q->limits.max_sectors = queue_max_hw_sectors(q); 5012 blk_queue_max_segments(q, USHRT_MAX); 5013 blk_queue_max_segment_size(q, UINT_MAX); 5014 blk_queue_io_min(q, rbd_dev->opts->alloc_size); 5015 blk_queue_io_opt(q, rbd_dev->opts->alloc_size); 5016 5017 if (rbd_dev->opts->trim) { 5018 blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); 5019 q->limits.discard_granularity = rbd_dev->opts->alloc_size; 5020 blk_queue_max_discard_sectors(q, objset_bytes >> SECTOR_SHIFT); 5021 blk_queue_max_write_zeroes_sectors(q, objset_bytes >> SECTOR_SHIFT); 5022 } 5023 5024 if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC)) 5025 q->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES; 5026 5027 /* 5028 * disk_release() expects a queue ref from add_disk() and will 5029 * put it. Hold an extra ref until add_disk() is called. 5030 */ 5031 WARN_ON(!blk_get_queue(q)); 5032 disk->queue = q; 5033 q->queuedata = rbd_dev; 5034 5035 rbd_dev->disk = disk; 5036 5037 return 0; 5038 out_tag_set: 5039 blk_mq_free_tag_set(&rbd_dev->tag_set); 5040 out_disk: 5041 put_disk(disk); 5042 return err; 5043 } 5044 5045 /* 5046 sysfs 5047 */ 5048 5049 static struct rbd_device *dev_to_rbd_dev(struct device *dev) 5050 { 5051 return container_of(dev, struct rbd_device, dev); 5052 } 5053 5054 static ssize_t rbd_size_show(struct device *dev, 5055 struct device_attribute *attr, char *buf) 5056 { 5057 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5058 5059 return sprintf(buf, "%llu\n", 5060 (unsigned long long)rbd_dev->mapping.size); 5061 } 5062 5063 static ssize_t rbd_features_show(struct device *dev, 5064 struct device_attribute *attr, char *buf) 5065 { 5066 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5067 5068 return sprintf(buf, "0x%016llx\n", rbd_dev->header.features); 5069 } 5070 5071 static ssize_t rbd_major_show(struct device *dev, 5072 struct device_attribute *attr, char *buf) 5073 { 5074 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5075 5076 if (rbd_dev->major) 5077 return sprintf(buf, "%d\n", rbd_dev->major); 5078 5079 return sprintf(buf, "(none)\n"); 5080 } 5081 5082 static ssize_t rbd_minor_show(struct device *dev, 5083 struct device_attribute *attr, char *buf) 5084 { 5085 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5086 5087 return sprintf(buf, "%d\n", rbd_dev->minor); 5088 } 5089 5090 static ssize_t rbd_client_addr_show(struct device *dev, 5091 struct device_attribute *attr, char *buf) 5092 { 5093 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5094 struct ceph_entity_addr *client_addr = 5095 ceph_client_addr(rbd_dev->rbd_client->client); 5096 5097 return sprintf(buf, "%pISpc/%u\n", &client_addr->in_addr, 5098 le32_to_cpu(client_addr->nonce)); 5099 } 5100 5101 static ssize_t rbd_client_id_show(struct device *dev, 5102 struct device_attribute *attr, char *buf) 5103 { 5104 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5105 5106 return sprintf(buf, "client%lld\n", 5107 ceph_client_gid(rbd_dev->rbd_client->client)); 5108 } 5109 5110 static ssize_t rbd_cluster_fsid_show(struct device *dev, 5111 struct device_attribute *attr, char *buf) 5112 { 5113 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5114 5115 return sprintf(buf, "%pU\n", &rbd_dev->rbd_client->client->fsid); 5116 } 5117 5118 static ssize_t rbd_config_info_show(struct device *dev, 5119 struct device_attribute *attr, char *buf) 5120 { 5121 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5122 5123 if (!capable(CAP_SYS_ADMIN)) 5124 return -EPERM; 5125 5126 return sprintf(buf, "%s\n", rbd_dev->config_info); 5127 } 5128 5129 static ssize_t rbd_pool_show(struct device *dev, 5130 struct device_attribute *attr, char *buf) 5131 { 5132 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5133 5134 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name); 5135 } 5136 5137 static ssize_t rbd_pool_id_show(struct device *dev, 5138 struct device_attribute *attr, char *buf) 5139 { 5140 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5141 5142 return sprintf(buf, "%llu\n", 5143 (unsigned long long) rbd_dev->spec->pool_id); 5144 } 5145 5146 static ssize_t rbd_pool_ns_show(struct device *dev, 5147 struct device_attribute *attr, char *buf) 5148 { 5149 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5150 5151 return sprintf(buf, "%s\n", rbd_dev->spec->pool_ns ?: ""); 5152 } 5153 5154 static ssize_t rbd_name_show(struct device *dev, 5155 struct device_attribute *attr, char *buf) 5156 { 5157 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5158 5159 if (rbd_dev->spec->image_name) 5160 return sprintf(buf, "%s\n", rbd_dev->spec->image_name); 5161 5162 return sprintf(buf, "(unknown)\n"); 5163 } 5164 5165 static ssize_t rbd_image_id_show(struct device *dev, 5166 struct device_attribute *attr, char *buf) 5167 { 5168 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5169 5170 return sprintf(buf, "%s\n", rbd_dev->spec->image_id); 5171 } 5172 5173 /* 5174 * Shows the name of the currently-mapped snapshot (or 5175 * RBD_SNAP_HEAD_NAME for the base image). 5176 */ 5177 static ssize_t rbd_snap_show(struct device *dev, 5178 struct device_attribute *attr, 5179 char *buf) 5180 { 5181 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5182 5183 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name); 5184 } 5185 5186 static ssize_t rbd_snap_id_show(struct device *dev, 5187 struct device_attribute *attr, char *buf) 5188 { 5189 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5190 5191 return sprintf(buf, "%llu\n", rbd_dev->spec->snap_id); 5192 } 5193 5194 /* 5195 * For a v2 image, shows the chain of parent images, separated by empty 5196 * lines. For v1 images or if there is no parent, shows "(no parent 5197 * image)". 5198 */ 5199 static ssize_t rbd_parent_show(struct device *dev, 5200 struct device_attribute *attr, 5201 char *buf) 5202 { 5203 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5204 ssize_t count = 0; 5205 5206 if (!rbd_dev->parent) 5207 return sprintf(buf, "(no parent image)\n"); 5208 5209 for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) { 5210 struct rbd_spec *spec = rbd_dev->parent_spec; 5211 5212 count += sprintf(&buf[count], "%s" 5213 "pool_id %llu\npool_name %s\n" 5214 "pool_ns %s\n" 5215 "image_id %s\nimage_name %s\n" 5216 "snap_id %llu\nsnap_name %s\n" 5217 "overlap %llu\n", 5218 !count ? "" : "\n", /* first? */ 5219 spec->pool_id, spec->pool_name, 5220 spec->pool_ns ?: "", 5221 spec->image_id, spec->image_name ?: "(unknown)", 5222 spec->snap_id, spec->snap_name, 5223 rbd_dev->parent_overlap); 5224 } 5225 5226 return count; 5227 } 5228 5229 static ssize_t rbd_image_refresh(struct device *dev, 5230 struct device_attribute *attr, 5231 const char *buf, 5232 size_t size) 5233 { 5234 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5235 int ret; 5236 5237 if (!capable(CAP_SYS_ADMIN)) 5238 return -EPERM; 5239 5240 ret = rbd_dev_refresh(rbd_dev); 5241 if (ret) 5242 return ret; 5243 5244 return size; 5245 } 5246 5247 static DEVICE_ATTR(size, 0444, rbd_size_show, NULL); 5248 static DEVICE_ATTR(features, 0444, rbd_features_show, NULL); 5249 static DEVICE_ATTR(major, 0444, rbd_major_show, NULL); 5250 static DEVICE_ATTR(minor, 0444, rbd_minor_show, NULL); 5251 static DEVICE_ATTR(client_addr, 0444, rbd_client_addr_show, NULL); 5252 static DEVICE_ATTR(client_id, 0444, rbd_client_id_show, NULL); 5253 static DEVICE_ATTR(cluster_fsid, 0444, rbd_cluster_fsid_show, NULL); 5254 static DEVICE_ATTR(config_info, 0400, rbd_config_info_show, NULL); 5255 static DEVICE_ATTR(pool, 0444, rbd_pool_show, NULL); 5256 static DEVICE_ATTR(pool_id, 0444, rbd_pool_id_show, NULL); 5257 static DEVICE_ATTR(pool_ns, 0444, rbd_pool_ns_show, NULL); 5258 static DEVICE_ATTR(name, 0444, rbd_name_show, NULL); 5259 static DEVICE_ATTR(image_id, 0444, rbd_image_id_show, NULL); 5260 static DEVICE_ATTR(refresh, 0200, NULL, rbd_image_refresh); 5261 static DEVICE_ATTR(current_snap, 0444, rbd_snap_show, NULL); 5262 static DEVICE_ATTR(snap_id, 0444, rbd_snap_id_show, NULL); 5263 static DEVICE_ATTR(parent, 0444, rbd_parent_show, NULL); 5264 5265 static struct attribute *rbd_attrs[] = { 5266 &dev_attr_size.attr, 5267 &dev_attr_features.attr, 5268 &dev_attr_major.attr, 5269 &dev_attr_minor.attr, 5270 &dev_attr_client_addr.attr, 5271 &dev_attr_client_id.attr, 5272 &dev_attr_cluster_fsid.attr, 5273 &dev_attr_config_info.attr, 5274 &dev_attr_pool.attr, 5275 &dev_attr_pool_id.attr, 5276 &dev_attr_pool_ns.attr, 5277 &dev_attr_name.attr, 5278 &dev_attr_image_id.attr, 5279 &dev_attr_current_snap.attr, 5280 &dev_attr_snap_id.attr, 5281 &dev_attr_parent.attr, 5282 &dev_attr_refresh.attr, 5283 NULL 5284 }; 5285 5286 static struct attribute_group rbd_attr_group = { 5287 .attrs = rbd_attrs, 5288 }; 5289 5290 static const struct attribute_group *rbd_attr_groups[] = { 5291 &rbd_attr_group, 5292 NULL 5293 }; 5294 5295 static void rbd_dev_release(struct device *dev); 5296 5297 static const struct device_type rbd_device_type = { 5298 .name = "rbd", 5299 .groups = rbd_attr_groups, 5300 .release = rbd_dev_release, 5301 }; 5302 5303 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec) 5304 { 5305 kref_get(&spec->kref); 5306 5307 return spec; 5308 } 5309 5310 static void rbd_spec_free(struct kref *kref); 5311 static void rbd_spec_put(struct rbd_spec *spec) 5312 { 5313 if (spec) 5314 kref_put(&spec->kref, rbd_spec_free); 5315 } 5316 5317 static struct rbd_spec *rbd_spec_alloc(void) 5318 { 5319 struct rbd_spec *spec; 5320 5321 spec = kzalloc(sizeof (*spec), GFP_KERNEL); 5322 if (!spec) 5323 return NULL; 5324 5325 spec->pool_id = CEPH_NOPOOL; 5326 spec->snap_id = CEPH_NOSNAP; 5327 kref_init(&spec->kref); 5328 5329 return spec; 5330 } 5331 5332 static void rbd_spec_free(struct kref *kref) 5333 { 5334 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref); 5335 5336 kfree(spec->pool_name); 5337 kfree(spec->pool_ns); 5338 kfree(spec->image_id); 5339 kfree(spec->image_name); 5340 kfree(spec->snap_name); 5341 kfree(spec); 5342 } 5343 5344 static void rbd_dev_free(struct rbd_device *rbd_dev) 5345 { 5346 WARN_ON(rbd_dev->watch_state != RBD_WATCH_STATE_UNREGISTERED); 5347 WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_UNLOCKED); 5348 5349 ceph_oid_destroy(&rbd_dev->header_oid); 5350 ceph_oloc_destroy(&rbd_dev->header_oloc); 5351 kfree(rbd_dev->config_info); 5352 5353 rbd_put_client(rbd_dev->rbd_client); 5354 rbd_spec_put(rbd_dev->spec); 5355 kfree(rbd_dev->opts); 5356 kfree(rbd_dev); 5357 } 5358 5359 static void rbd_dev_release(struct device *dev) 5360 { 5361 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5362 bool need_put = !!rbd_dev->opts; 5363 5364 if (need_put) { 5365 destroy_workqueue(rbd_dev->task_wq); 5366 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); 5367 } 5368 5369 rbd_dev_free(rbd_dev); 5370 5371 /* 5372 * This is racy, but way better than putting module outside of 5373 * the release callback. The race window is pretty small, so 5374 * doing something similar to dm (dm-builtin.c) is overkill. 5375 */ 5376 if (need_put) 5377 module_put(THIS_MODULE); 5378 } 5379 5380 static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc, 5381 struct rbd_spec *spec) 5382 { 5383 struct rbd_device *rbd_dev; 5384 5385 rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL); 5386 if (!rbd_dev) 5387 return NULL; 5388 5389 spin_lock_init(&rbd_dev->lock); 5390 INIT_LIST_HEAD(&rbd_dev->node); 5391 init_rwsem(&rbd_dev->header_rwsem); 5392 5393 rbd_dev->header.data_pool_id = CEPH_NOPOOL; 5394 ceph_oid_init(&rbd_dev->header_oid); 5395 rbd_dev->header_oloc.pool = spec->pool_id; 5396 if (spec->pool_ns) { 5397 WARN_ON(!*spec->pool_ns); 5398 rbd_dev->header_oloc.pool_ns = 5399 ceph_find_or_create_string(spec->pool_ns, 5400 strlen(spec->pool_ns)); 5401 } 5402 5403 mutex_init(&rbd_dev->watch_mutex); 5404 rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED; 5405 INIT_DELAYED_WORK(&rbd_dev->watch_dwork, rbd_reregister_watch); 5406 5407 init_rwsem(&rbd_dev->lock_rwsem); 5408 rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED; 5409 INIT_WORK(&rbd_dev->acquired_lock_work, rbd_notify_acquired_lock); 5410 INIT_WORK(&rbd_dev->released_lock_work, rbd_notify_released_lock); 5411 INIT_DELAYED_WORK(&rbd_dev->lock_dwork, rbd_acquire_lock); 5412 INIT_WORK(&rbd_dev->unlock_work, rbd_release_lock_work); 5413 spin_lock_init(&rbd_dev->lock_lists_lock); 5414 INIT_LIST_HEAD(&rbd_dev->acquiring_list); 5415 INIT_LIST_HEAD(&rbd_dev->running_list); 5416 init_completion(&rbd_dev->acquire_wait); 5417 init_completion(&rbd_dev->releasing_wait); 5418 5419 spin_lock_init(&rbd_dev->object_map_lock); 5420 5421 rbd_dev->dev.bus = &rbd_bus_type; 5422 rbd_dev->dev.type = &rbd_device_type; 5423 rbd_dev->dev.parent = &rbd_root_dev; 5424 device_initialize(&rbd_dev->dev); 5425 5426 rbd_dev->rbd_client = rbdc; 5427 rbd_dev->spec = spec; 5428 5429 return rbd_dev; 5430 } 5431 5432 /* 5433 * Create a mapping rbd_dev. 5434 */ 5435 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, 5436 struct rbd_spec *spec, 5437 struct rbd_options *opts) 5438 { 5439 struct rbd_device *rbd_dev; 5440 5441 rbd_dev = __rbd_dev_create(rbdc, spec); 5442 if (!rbd_dev) 5443 return NULL; 5444 5445 rbd_dev->opts = opts; 5446 5447 /* get an id and fill in device name */ 5448 rbd_dev->dev_id = ida_simple_get(&rbd_dev_id_ida, 0, 5449 minor_to_rbd_dev_id(1 << MINORBITS), 5450 GFP_KERNEL); 5451 if (rbd_dev->dev_id < 0) 5452 goto fail_rbd_dev; 5453 5454 sprintf(rbd_dev->name, RBD_DRV_NAME "%d", rbd_dev->dev_id); 5455 rbd_dev->task_wq = alloc_ordered_workqueue("%s-tasks", WQ_MEM_RECLAIM, 5456 rbd_dev->name); 5457 if (!rbd_dev->task_wq) 5458 goto fail_dev_id; 5459 5460 /* we have a ref from do_rbd_add() */ 5461 __module_get(THIS_MODULE); 5462 5463 dout("%s rbd_dev %p dev_id %d\n", __func__, rbd_dev, rbd_dev->dev_id); 5464 return rbd_dev; 5465 5466 fail_dev_id: 5467 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); 5468 fail_rbd_dev: 5469 rbd_dev_free(rbd_dev); 5470 return NULL; 5471 } 5472 5473 static void rbd_dev_destroy(struct rbd_device *rbd_dev) 5474 { 5475 if (rbd_dev) 5476 put_device(&rbd_dev->dev); 5477 } 5478 5479 /* 5480 * Get the size and object order for an image snapshot, or if 5481 * snap_id is CEPH_NOSNAP, gets this information for the base 5482 * image. 5483 */ 5484 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 5485 u8 *order, u64 *snap_size) 5486 { 5487 __le64 snapid = cpu_to_le64(snap_id); 5488 int ret; 5489 struct { 5490 u8 order; 5491 __le64 size; 5492 } __attribute__ ((packed)) size_buf = { 0 }; 5493 5494 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 5495 &rbd_dev->header_oloc, "get_size", 5496 &snapid, sizeof(snapid), 5497 &size_buf, sizeof(size_buf)); 5498 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 5499 if (ret < 0) 5500 return ret; 5501 if (ret < sizeof (size_buf)) 5502 return -ERANGE; 5503 5504 if (order) { 5505 *order = size_buf.order; 5506 dout(" order %u", (unsigned int)*order); 5507 } 5508 *snap_size = le64_to_cpu(size_buf.size); 5509 5510 dout(" snap_id 0x%016llx snap_size = %llu\n", 5511 (unsigned long long)snap_id, 5512 (unsigned long long)*snap_size); 5513 5514 return 0; 5515 } 5516 5517 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev) 5518 { 5519 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP, 5520 &rbd_dev->header.obj_order, 5521 &rbd_dev->header.image_size); 5522 } 5523 5524 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev) 5525 { 5526 size_t size; 5527 void *reply_buf; 5528 int ret; 5529 void *p; 5530 5531 /* Response will be an encoded string, which includes a length */ 5532 size = sizeof(__le32) + RBD_OBJ_PREFIX_LEN_MAX; 5533 reply_buf = kzalloc(size, GFP_KERNEL); 5534 if (!reply_buf) 5535 return -ENOMEM; 5536 5537 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 5538 &rbd_dev->header_oloc, "get_object_prefix", 5539 NULL, 0, reply_buf, size); 5540 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 5541 if (ret < 0) 5542 goto out; 5543 5544 p = reply_buf; 5545 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p, 5546 p + ret, NULL, GFP_NOIO); 5547 ret = 0; 5548 5549 if (IS_ERR(rbd_dev->header.object_prefix)) { 5550 ret = PTR_ERR(rbd_dev->header.object_prefix); 5551 rbd_dev->header.object_prefix = NULL; 5552 } else { 5553 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix); 5554 } 5555 out: 5556 kfree(reply_buf); 5557 5558 return ret; 5559 } 5560 5561 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, 5562 bool read_only, u64 *snap_features) 5563 { 5564 struct { 5565 __le64 snap_id; 5566 u8 read_only; 5567 } features_in; 5568 struct { 5569 __le64 features; 5570 __le64 incompat; 5571 } __attribute__ ((packed)) features_buf = { 0 }; 5572 u64 unsup; 5573 int ret; 5574 5575 features_in.snap_id = cpu_to_le64(snap_id); 5576 features_in.read_only = read_only; 5577 5578 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 5579 &rbd_dev->header_oloc, "get_features", 5580 &features_in, sizeof(features_in), 5581 &features_buf, sizeof(features_buf)); 5582 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 5583 if (ret < 0) 5584 return ret; 5585 if (ret < sizeof (features_buf)) 5586 return -ERANGE; 5587 5588 unsup = le64_to_cpu(features_buf.incompat) & ~RBD_FEATURES_SUPPORTED; 5589 if (unsup) { 5590 rbd_warn(rbd_dev, "image uses unsupported features: 0x%llx", 5591 unsup); 5592 return -ENXIO; 5593 } 5594 5595 *snap_features = le64_to_cpu(features_buf.features); 5596 5597 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n", 5598 (unsigned long long)snap_id, 5599 (unsigned long long)*snap_features, 5600 (unsigned long long)le64_to_cpu(features_buf.incompat)); 5601 5602 return 0; 5603 } 5604 5605 static int rbd_dev_v2_features(struct rbd_device *rbd_dev) 5606 { 5607 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP, 5608 rbd_is_ro(rbd_dev), 5609 &rbd_dev->header.features); 5610 } 5611 5612 /* 5613 * These are generic image flags, but since they are used only for 5614 * object map, store them in rbd_dev->object_map_flags. 5615 * 5616 * For the same reason, this function is called only on object map 5617 * (re)load and not on header refresh. 5618 */ 5619 static int rbd_dev_v2_get_flags(struct rbd_device *rbd_dev) 5620 { 5621 __le64 snapid = cpu_to_le64(rbd_dev->spec->snap_id); 5622 __le64 flags; 5623 int ret; 5624 5625 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 5626 &rbd_dev->header_oloc, "get_flags", 5627 &snapid, sizeof(snapid), 5628 &flags, sizeof(flags)); 5629 if (ret < 0) 5630 return ret; 5631 if (ret < sizeof(flags)) 5632 return -EBADMSG; 5633 5634 rbd_dev->object_map_flags = le64_to_cpu(flags); 5635 return 0; 5636 } 5637 5638 struct parent_image_info { 5639 u64 pool_id; 5640 const char *pool_ns; 5641 const char *image_id; 5642 u64 snap_id; 5643 5644 bool has_overlap; 5645 u64 overlap; 5646 }; 5647 5648 /* 5649 * The caller is responsible for @pii. 5650 */ 5651 static int decode_parent_image_spec(void **p, void *end, 5652 struct parent_image_info *pii) 5653 { 5654 u8 struct_v; 5655 u32 struct_len; 5656 int ret; 5657 5658 ret = ceph_start_decoding(p, end, 1, "ParentImageSpec", 5659 &struct_v, &struct_len); 5660 if (ret) 5661 return ret; 5662 5663 ceph_decode_64_safe(p, end, pii->pool_id, e_inval); 5664 pii->pool_ns = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL); 5665 if (IS_ERR(pii->pool_ns)) { 5666 ret = PTR_ERR(pii->pool_ns); 5667 pii->pool_ns = NULL; 5668 return ret; 5669 } 5670 pii->image_id = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL); 5671 if (IS_ERR(pii->image_id)) { 5672 ret = PTR_ERR(pii->image_id); 5673 pii->image_id = NULL; 5674 return ret; 5675 } 5676 ceph_decode_64_safe(p, end, pii->snap_id, e_inval); 5677 return 0; 5678 5679 e_inval: 5680 return -EINVAL; 5681 } 5682 5683 static int __get_parent_info(struct rbd_device *rbd_dev, 5684 struct page *req_page, 5685 struct page *reply_page, 5686 struct parent_image_info *pii) 5687 { 5688 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 5689 size_t reply_len = PAGE_SIZE; 5690 void *p, *end; 5691 int ret; 5692 5693 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 5694 "rbd", "parent_get", CEPH_OSD_FLAG_READ, 5695 req_page, sizeof(u64), &reply_page, &reply_len); 5696 if (ret) 5697 return ret == -EOPNOTSUPP ? 1 : ret; 5698 5699 p = page_address(reply_page); 5700 end = p + reply_len; 5701 ret = decode_parent_image_spec(&p, end, pii); 5702 if (ret) 5703 return ret; 5704 5705 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 5706 "rbd", "parent_overlap_get", CEPH_OSD_FLAG_READ, 5707 req_page, sizeof(u64), &reply_page, &reply_len); 5708 if (ret) 5709 return ret; 5710 5711 p = page_address(reply_page); 5712 end = p + reply_len; 5713 ceph_decode_8_safe(&p, end, pii->has_overlap, e_inval); 5714 if (pii->has_overlap) 5715 ceph_decode_64_safe(&p, end, pii->overlap, e_inval); 5716 5717 return 0; 5718 5719 e_inval: 5720 return -EINVAL; 5721 } 5722 5723 /* 5724 * The caller is responsible for @pii. 5725 */ 5726 static int __get_parent_info_legacy(struct rbd_device *rbd_dev, 5727 struct page *req_page, 5728 struct page *reply_page, 5729 struct parent_image_info *pii) 5730 { 5731 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 5732 size_t reply_len = PAGE_SIZE; 5733 void *p, *end; 5734 int ret; 5735 5736 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc, 5737 "rbd", "get_parent", CEPH_OSD_FLAG_READ, 5738 req_page, sizeof(u64), &reply_page, &reply_len); 5739 if (ret) 5740 return ret; 5741 5742 p = page_address(reply_page); 5743 end = p + reply_len; 5744 ceph_decode_64_safe(&p, end, pii->pool_id, e_inval); 5745 pii->image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL); 5746 if (IS_ERR(pii->image_id)) { 5747 ret = PTR_ERR(pii->image_id); 5748 pii->image_id = NULL; 5749 return ret; 5750 } 5751 ceph_decode_64_safe(&p, end, pii->snap_id, e_inval); 5752 pii->has_overlap = true; 5753 ceph_decode_64_safe(&p, end, pii->overlap, e_inval); 5754 5755 return 0; 5756 5757 e_inval: 5758 return -EINVAL; 5759 } 5760 5761 static int get_parent_info(struct rbd_device *rbd_dev, 5762 struct parent_image_info *pii) 5763 { 5764 struct page *req_page, *reply_page; 5765 void *p; 5766 int ret; 5767 5768 req_page = alloc_page(GFP_KERNEL); 5769 if (!req_page) 5770 return -ENOMEM; 5771 5772 reply_page = alloc_page(GFP_KERNEL); 5773 if (!reply_page) { 5774 __free_page(req_page); 5775 return -ENOMEM; 5776 } 5777 5778 p = page_address(req_page); 5779 ceph_encode_64(&p, rbd_dev->spec->snap_id); 5780 ret = __get_parent_info(rbd_dev, req_page, reply_page, pii); 5781 if (ret > 0) 5782 ret = __get_parent_info_legacy(rbd_dev, req_page, reply_page, 5783 pii); 5784 5785 __free_page(req_page); 5786 __free_page(reply_page); 5787 return ret; 5788 } 5789 5790 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev) 5791 { 5792 struct rbd_spec *parent_spec; 5793 struct parent_image_info pii = { 0 }; 5794 int ret; 5795 5796 parent_spec = rbd_spec_alloc(); 5797 if (!parent_spec) 5798 return -ENOMEM; 5799 5800 ret = get_parent_info(rbd_dev, &pii); 5801 if (ret) 5802 goto out_err; 5803 5804 dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n", 5805 __func__, pii.pool_id, pii.pool_ns, pii.image_id, pii.snap_id, 5806 pii.has_overlap, pii.overlap); 5807 5808 if (pii.pool_id == CEPH_NOPOOL || !pii.has_overlap) { 5809 /* 5810 * Either the parent never existed, or we have 5811 * record of it but the image got flattened so it no 5812 * longer has a parent. When the parent of a 5813 * layered image disappears we immediately set the 5814 * overlap to 0. The effect of this is that all new 5815 * requests will be treated as if the image had no 5816 * parent. 5817 * 5818 * If !pii.has_overlap, the parent image spec is not 5819 * applicable. It's there to avoid duplication in each 5820 * snapshot record. 5821 */ 5822 if (rbd_dev->parent_overlap) { 5823 rbd_dev->parent_overlap = 0; 5824 rbd_dev_parent_put(rbd_dev); 5825 pr_info("%s: clone image has been flattened\n", 5826 rbd_dev->disk->disk_name); 5827 } 5828 5829 goto out; /* No parent? No problem. */ 5830 } 5831 5832 /* The ceph file layout needs to fit pool id in 32 bits */ 5833 5834 ret = -EIO; 5835 if (pii.pool_id > (u64)U32_MAX) { 5836 rbd_warn(NULL, "parent pool id too large (%llu > %u)", 5837 (unsigned long long)pii.pool_id, U32_MAX); 5838 goto out_err; 5839 } 5840 5841 /* 5842 * The parent won't change (except when the clone is 5843 * flattened, already handled that). So we only need to 5844 * record the parent spec we have not already done so. 5845 */ 5846 if (!rbd_dev->parent_spec) { 5847 parent_spec->pool_id = pii.pool_id; 5848 if (pii.pool_ns && *pii.pool_ns) { 5849 parent_spec->pool_ns = pii.pool_ns; 5850 pii.pool_ns = NULL; 5851 } 5852 parent_spec->image_id = pii.image_id; 5853 pii.image_id = NULL; 5854 parent_spec->snap_id = pii.snap_id; 5855 5856 rbd_dev->parent_spec = parent_spec; 5857 parent_spec = NULL; /* rbd_dev now owns this */ 5858 } 5859 5860 /* 5861 * We always update the parent overlap. If it's zero we issue 5862 * a warning, as we will proceed as if there was no parent. 5863 */ 5864 if (!pii.overlap) { 5865 if (parent_spec) { 5866 /* refresh, careful to warn just once */ 5867 if (rbd_dev->parent_overlap) 5868 rbd_warn(rbd_dev, 5869 "clone now standalone (overlap became 0)"); 5870 } else { 5871 /* initial probe */ 5872 rbd_warn(rbd_dev, "clone is standalone (overlap 0)"); 5873 } 5874 } 5875 rbd_dev->parent_overlap = pii.overlap; 5876 5877 out: 5878 ret = 0; 5879 out_err: 5880 kfree(pii.pool_ns); 5881 kfree(pii.image_id); 5882 rbd_spec_put(parent_spec); 5883 return ret; 5884 } 5885 5886 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev) 5887 { 5888 struct { 5889 __le64 stripe_unit; 5890 __le64 stripe_count; 5891 } __attribute__ ((packed)) striping_info_buf = { 0 }; 5892 size_t size = sizeof (striping_info_buf); 5893 void *p; 5894 int ret; 5895 5896 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 5897 &rbd_dev->header_oloc, "get_stripe_unit_count", 5898 NULL, 0, &striping_info_buf, size); 5899 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 5900 if (ret < 0) 5901 return ret; 5902 if (ret < size) 5903 return -ERANGE; 5904 5905 p = &striping_info_buf; 5906 rbd_dev->header.stripe_unit = ceph_decode_64(&p); 5907 rbd_dev->header.stripe_count = ceph_decode_64(&p); 5908 return 0; 5909 } 5910 5911 static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev) 5912 { 5913 __le64 data_pool_id; 5914 int ret; 5915 5916 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 5917 &rbd_dev->header_oloc, "get_data_pool", 5918 NULL, 0, &data_pool_id, sizeof(data_pool_id)); 5919 if (ret < 0) 5920 return ret; 5921 if (ret < sizeof(data_pool_id)) 5922 return -EBADMSG; 5923 5924 rbd_dev->header.data_pool_id = le64_to_cpu(data_pool_id); 5925 WARN_ON(rbd_dev->header.data_pool_id == CEPH_NOPOOL); 5926 return 0; 5927 } 5928 5929 static char *rbd_dev_image_name(struct rbd_device *rbd_dev) 5930 { 5931 CEPH_DEFINE_OID_ONSTACK(oid); 5932 size_t image_id_size; 5933 char *image_id; 5934 void *p; 5935 void *end; 5936 size_t size; 5937 void *reply_buf = NULL; 5938 size_t len = 0; 5939 char *image_name = NULL; 5940 int ret; 5941 5942 rbd_assert(!rbd_dev->spec->image_name); 5943 5944 len = strlen(rbd_dev->spec->image_id); 5945 image_id_size = sizeof (__le32) + len; 5946 image_id = kmalloc(image_id_size, GFP_KERNEL); 5947 if (!image_id) 5948 return NULL; 5949 5950 p = image_id; 5951 end = image_id + image_id_size; 5952 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len); 5953 5954 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX; 5955 reply_buf = kmalloc(size, GFP_KERNEL); 5956 if (!reply_buf) 5957 goto out; 5958 5959 ceph_oid_printf(&oid, "%s", RBD_DIRECTORY); 5960 ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc, 5961 "dir_get_name", image_id, image_id_size, 5962 reply_buf, size); 5963 if (ret < 0) 5964 goto out; 5965 p = reply_buf; 5966 end = reply_buf + ret; 5967 5968 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL); 5969 if (IS_ERR(image_name)) 5970 image_name = NULL; 5971 else 5972 dout("%s: name is %s len is %zd\n", __func__, image_name, len); 5973 out: 5974 kfree(reply_buf); 5975 kfree(image_id); 5976 5977 return image_name; 5978 } 5979 5980 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 5981 { 5982 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 5983 const char *snap_name; 5984 u32 which = 0; 5985 5986 /* Skip over names until we find the one we are looking for */ 5987 5988 snap_name = rbd_dev->header.snap_names; 5989 while (which < snapc->num_snaps) { 5990 if (!strcmp(name, snap_name)) 5991 return snapc->snaps[which]; 5992 snap_name += strlen(snap_name) + 1; 5993 which++; 5994 } 5995 return CEPH_NOSNAP; 5996 } 5997 5998 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 5999 { 6000 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 6001 u32 which; 6002 bool found = false; 6003 u64 snap_id; 6004 6005 for (which = 0; !found && which < snapc->num_snaps; which++) { 6006 const char *snap_name; 6007 6008 snap_id = snapc->snaps[which]; 6009 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id); 6010 if (IS_ERR(snap_name)) { 6011 /* ignore no-longer existing snapshots */ 6012 if (PTR_ERR(snap_name) == -ENOENT) 6013 continue; 6014 else 6015 break; 6016 } 6017 found = !strcmp(name, snap_name); 6018 kfree(snap_name); 6019 } 6020 return found ? snap_id : CEPH_NOSNAP; 6021 } 6022 6023 /* 6024 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if 6025 * no snapshot by that name is found, or if an error occurs. 6026 */ 6027 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 6028 { 6029 if (rbd_dev->image_format == 1) 6030 return rbd_v1_snap_id_by_name(rbd_dev, name); 6031 6032 return rbd_v2_snap_id_by_name(rbd_dev, name); 6033 } 6034 6035 /* 6036 * An image being mapped will have everything but the snap id. 6037 */ 6038 static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev) 6039 { 6040 struct rbd_spec *spec = rbd_dev->spec; 6041 6042 rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name); 6043 rbd_assert(spec->image_id && spec->image_name); 6044 rbd_assert(spec->snap_name); 6045 6046 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) { 6047 u64 snap_id; 6048 6049 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name); 6050 if (snap_id == CEPH_NOSNAP) 6051 return -ENOENT; 6052 6053 spec->snap_id = snap_id; 6054 } else { 6055 spec->snap_id = CEPH_NOSNAP; 6056 } 6057 6058 return 0; 6059 } 6060 6061 /* 6062 * A parent image will have all ids but none of the names. 6063 * 6064 * All names in an rbd spec are dynamically allocated. It's OK if we 6065 * can't figure out the name for an image id. 6066 */ 6067 static int rbd_spec_fill_names(struct rbd_device *rbd_dev) 6068 { 6069 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 6070 struct rbd_spec *spec = rbd_dev->spec; 6071 const char *pool_name; 6072 const char *image_name; 6073 const char *snap_name; 6074 int ret; 6075 6076 rbd_assert(spec->pool_id != CEPH_NOPOOL); 6077 rbd_assert(spec->image_id); 6078 rbd_assert(spec->snap_id != CEPH_NOSNAP); 6079 6080 /* Get the pool name; we have to make our own copy of this */ 6081 6082 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id); 6083 if (!pool_name) { 6084 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id); 6085 return -EIO; 6086 } 6087 pool_name = kstrdup(pool_name, GFP_KERNEL); 6088 if (!pool_name) 6089 return -ENOMEM; 6090 6091 /* Fetch the image name; tolerate failure here */ 6092 6093 image_name = rbd_dev_image_name(rbd_dev); 6094 if (!image_name) 6095 rbd_warn(rbd_dev, "unable to get image name"); 6096 6097 /* Fetch the snapshot name */ 6098 6099 snap_name = rbd_snap_name(rbd_dev, spec->snap_id); 6100 if (IS_ERR(snap_name)) { 6101 ret = PTR_ERR(snap_name); 6102 goto out_err; 6103 } 6104 6105 spec->pool_name = pool_name; 6106 spec->image_name = image_name; 6107 spec->snap_name = snap_name; 6108 6109 return 0; 6110 6111 out_err: 6112 kfree(image_name); 6113 kfree(pool_name); 6114 return ret; 6115 } 6116 6117 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev) 6118 { 6119 size_t size; 6120 int ret; 6121 void *reply_buf; 6122 void *p; 6123 void *end; 6124 u64 seq; 6125 u32 snap_count; 6126 struct ceph_snap_context *snapc; 6127 u32 i; 6128 6129 /* 6130 * We'll need room for the seq value (maximum snapshot id), 6131 * snapshot count, and array of that many snapshot ids. 6132 * For now we have a fixed upper limit on the number we're 6133 * prepared to receive. 6134 */ 6135 size = sizeof (__le64) + sizeof (__le32) + 6136 RBD_MAX_SNAP_COUNT * sizeof (__le64); 6137 reply_buf = kzalloc(size, GFP_KERNEL); 6138 if (!reply_buf) 6139 return -ENOMEM; 6140 6141 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 6142 &rbd_dev->header_oloc, "get_snapcontext", 6143 NULL, 0, reply_buf, size); 6144 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 6145 if (ret < 0) 6146 goto out; 6147 6148 p = reply_buf; 6149 end = reply_buf + ret; 6150 ret = -ERANGE; 6151 ceph_decode_64_safe(&p, end, seq, out); 6152 ceph_decode_32_safe(&p, end, snap_count, out); 6153 6154 /* 6155 * Make sure the reported number of snapshot ids wouldn't go 6156 * beyond the end of our buffer. But before checking that, 6157 * make sure the computed size of the snapshot context we 6158 * allocate is representable in a size_t. 6159 */ 6160 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context)) 6161 / sizeof (u64)) { 6162 ret = -EINVAL; 6163 goto out; 6164 } 6165 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64))) 6166 goto out; 6167 ret = 0; 6168 6169 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); 6170 if (!snapc) { 6171 ret = -ENOMEM; 6172 goto out; 6173 } 6174 snapc->seq = seq; 6175 for (i = 0; i < snap_count; i++) 6176 snapc->snaps[i] = ceph_decode_64(&p); 6177 6178 ceph_put_snap_context(rbd_dev->header.snapc); 6179 rbd_dev->header.snapc = snapc; 6180 6181 dout(" snap context seq = %llu, snap_count = %u\n", 6182 (unsigned long long)seq, (unsigned int)snap_count); 6183 out: 6184 kfree(reply_buf); 6185 6186 return ret; 6187 } 6188 6189 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, 6190 u64 snap_id) 6191 { 6192 size_t size; 6193 void *reply_buf; 6194 __le64 snapid; 6195 int ret; 6196 void *p; 6197 void *end; 6198 char *snap_name; 6199 6200 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN; 6201 reply_buf = kmalloc(size, GFP_KERNEL); 6202 if (!reply_buf) 6203 return ERR_PTR(-ENOMEM); 6204 6205 snapid = cpu_to_le64(snap_id); 6206 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid, 6207 &rbd_dev->header_oloc, "get_snapshot_name", 6208 &snapid, sizeof(snapid), reply_buf, size); 6209 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 6210 if (ret < 0) { 6211 snap_name = ERR_PTR(ret); 6212 goto out; 6213 } 6214 6215 p = reply_buf; 6216 end = reply_buf + ret; 6217 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL); 6218 if (IS_ERR(snap_name)) 6219 goto out; 6220 6221 dout(" snap_id 0x%016llx snap_name = %s\n", 6222 (unsigned long long)snap_id, snap_name); 6223 out: 6224 kfree(reply_buf); 6225 6226 return snap_name; 6227 } 6228 6229 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev) 6230 { 6231 bool first_time = rbd_dev->header.object_prefix == NULL; 6232 int ret; 6233 6234 ret = rbd_dev_v2_image_size(rbd_dev); 6235 if (ret) 6236 return ret; 6237 6238 if (first_time) { 6239 ret = rbd_dev_v2_header_onetime(rbd_dev); 6240 if (ret) 6241 return ret; 6242 } 6243 6244 ret = rbd_dev_v2_snap_context(rbd_dev); 6245 if (ret && first_time) { 6246 kfree(rbd_dev->header.object_prefix); 6247 rbd_dev->header.object_prefix = NULL; 6248 } 6249 6250 return ret; 6251 } 6252 6253 static int rbd_dev_header_info(struct rbd_device *rbd_dev) 6254 { 6255 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 6256 6257 if (rbd_dev->image_format == 1) 6258 return rbd_dev_v1_header_info(rbd_dev); 6259 6260 return rbd_dev_v2_header_info(rbd_dev); 6261 } 6262 6263 /* 6264 * Skips over white space at *buf, and updates *buf to point to the 6265 * first found non-space character (if any). Returns the length of 6266 * the token (string of non-white space characters) found. Note 6267 * that *buf must be terminated with '\0'. 6268 */ 6269 static inline size_t next_token(const char **buf) 6270 { 6271 /* 6272 * These are the characters that produce nonzero for 6273 * isspace() in the "C" and "POSIX" locales. 6274 */ 6275 const char *spaces = " \f\n\r\t\v"; 6276 6277 *buf += strspn(*buf, spaces); /* Find start of token */ 6278 6279 return strcspn(*buf, spaces); /* Return token length */ 6280 } 6281 6282 /* 6283 * Finds the next token in *buf, dynamically allocates a buffer big 6284 * enough to hold a copy of it, and copies the token into the new 6285 * buffer. The copy is guaranteed to be terminated with '\0'. Note 6286 * that a duplicate buffer is created even for a zero-length token. 6287 * 6288 * Returns a pointer to the newly-allocated duplicate, or a null 6289 * pointer if memory for the duplicate was not available. If 6290 * the lenp argument is a non-null pointer, the length of the token 6291 * (not including the '\0') is returned in *lenp. 6292 * 6293 * If successful, the *buf pointer will be updated to point beyond 6294 * the end of the found token. 6295 * 6296 * Note: uses GFP_KERNEL for allocation. 6297 */ 6298 static inline char *dup_token(const char **buf, size_t *lenp) 6299 { 6300 char *dup; 6301 size_t len; 6302 6303 len = next_token(buf); 6304 dup = kmemdup(*buf, len + 1, GFP_KERNEL); 6305 if (!dup) 6306 return NULL; 6307 *(dup + len) = '\0'; 6308 *buf += len; 6309 6310 if (lenp) 6311 *lenp = len; 6312 6313 return dup; 6314 } 6315 6316 static int rbd_parse_param(struct fs_parameter *param, 6317 struct rbd_parse_opts_ctx *pctx) 6318 { 6319 struct rbd_options *opt = pctx->opts; 6320 struct fs_parse_result result; 6321 struct p_log log = {.prefix = "rbd"}; 6322 int token, ret; 6323 6324 ret = ceph_parse_param(param, pctx->copts, NULL); 6325 if (ret != -ENOPARAM) 6326 return ret; 6327 6328 token = __fs_parse(&log, rbd_parameters, param, &result); 6329 dout("%s fs_parse '%s' token %d\n", __func__, param->key, token); 6330 if (token < 0) { 6331 if (token == -ENOPARAM) 6332 return inval_plog(&log, "Unknown parameter '%s'", 6333 param->key); 6334 return token; 6335 } 6336 6337 switch (token) { 6338 case Opt_queue_depth: 6339 if (result.uint_32 < 1) 6340 goto out_of_range; 6341 opt->queue_depth = result.uint_32; 6342 break; 6343 case Opt_alloc_size: 6344 if (result.uint_32 < SECTOR_SIZE) 6345 goto out_of_range; 6346 if (!is_power_of_2(result.uint_32)) 6347 return inval_plog(&log, "alloc_size must be a power of 2"); 6348 opt->alloc_size = result.uint_32; 6349 break; 6350 case Opt_lock_timeout: 6351 /* 0 is "wait forever" (i.e. infinite timeout) */ 6352 if (result.uint_32 > INT_MAX / 1000) 6353 goto out_of_range; 6354 opt->lock_timeout = msecs_to_jiffies(result.uint_32 * 1000); 6355 break; 6356 case Opt_pool_ns: 6357 kfree(pctx->spec->pool_ns); 6358 pctx->spec->pool_ns = param->string; 6359 param->string = NULL; 6360 break; 6361 case Opt_compression_hint: 6362 switch (result.uint_32) { 6363 case Opt_compression_hint_none: 6364 opt->alloc_hint_flags &= 6365 ~(CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE | 6366 CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE); 6367 break; 6368 case Opt_compression_hint_compressible: 6369 opt->alloc_hint_flags |= 6370 CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE; 6371 opt->alloc_hint_flags &= 6372 ~CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE; 6373 break; 6374 case Opt_compression_hint_incompressible: 6375 opt->alloc_hint_flags |= 6376 CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE; 6377 opt->alloc_hint_flags &= 6378 ~CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE; 6379 break; 6380 default: 6381 BUG(); 6382 } 6383 break; 6384 case Opt_read_only: 6385 opt->read_only = true; 6386 break; 6387 case Opt_read_write: 6388 opt->read_only = false; 6389 break; 6390 case Opt_lock_on_read: 6391 opt->lock_on_read = true; 6392 break; 6393 case Opt_exclusive: 6394 opt->exclusive = true; 6395 break; 6396 case Opt_notrim: 6397 opt->trim = false; 6398 break; 6399 default: 6400 BUG(); 6401 } 6402 6403 return 0; 6404 6405 out_of_range: 6406 return inval_plog(&log, "%s out of range", param->key); 6407 } 6408 6409 /* 6410 * This duplicates most of generic_parse_monolithic(), untying it from 6411 * fs_context and skipping standard superblock and security options. 6412 */ 6413 static int rbd_parse_options(char *options, struct rbd_parse_opts_ctx *pctx) 6414 { 6415 char *key; 6416 int ret = 0; 6417 6418 dout("%s '%s'\n", __func__, options); 6419 while ((key = strsep(&options, ",")) != NULL) { 6420 if (*key) { 6421 struct fs_parameter param = { 6422 .key = key, 6423 .type = fs_value_is_flag, 6424 }; 6425 char *value = strchr(key, '='); 6426 size_t v_len = 0; 6427 6428 if (value) { 6429 if (value == key) 6430 continue; 6431 *value++ = 0; 6432 v_len = strlen(value); 6433 param.string = kmemdup_nul(value, v_len, 6434 GFP_KERNEL); 6435 if (!param.string) 6436 return -ENOMEM; 6437 param.type = fs_value_is_string; 6438 } 6439 param.size = v_len; 6440 6441 ret = rbd_parse_param(¶m, pctx); 6442 kfree(param.string); 6443 if (ret) 6444 break; 6445 } 6446 } 6447 6448 return ret; 6449 } 6450 6451 /* 6452 * Parse the options provided for an "rbd add" (i.e., rbd image 6453 * mapping) request. These arrive via a write to /sys/bus/rbd/add, 6454 * and the data written is passed here via a NUL-terminated buffer. 6455 * Returns 0 if successful or an error code otherwise. 6456 * 6457 * The information extracted from these options is recorded in 6458 * the other parameters which return dynamically-allocated 6459 * structures: 6460 * ceph_opts 6461 * The address of a pointer that will refer to a ceph options 6462 * structure. Caller must release the returned pointer using 6463 * ceph_destroy_options() when it is no longer needed. 6464 * rbd_opts 6465 * Address of an rbd options pointer. Fully initialized by 6466 * this function; caller must release with kfree(). 6467 * spec 6468 * Address of an rbd image specification pointer. Fully 6469 * initialized by this function based on parsed options. 6470 * Caller must release with rbd_spec_put(). 6471 * 6472 * The options passed take this form: 6473 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>] 6474 * where: 6475 * <mon_addrs> 6476 * A comma-separated list of one or more monitor addresses. 6477 * A monitor address is an ip address, optionally followed 6478 * by a port number (separated by a colon). 6479 * I.e.: ip1[:port1][,ip2[:port2]...] 6480 * <options> 6481 * A comma-separated list of ceph and/or rbd options. 6482 * <pool_name> 6483 * The name of the rados pool containing the rbd image. 6484 * <image_name> 6485 * The name of the image in that pool to map. 6486 * <snap_id> 6487 * An optional snapshot id. If provided, the mapping will 6488 * present data from the image at the time that snapshot was 6489 * created. The image head is used if no snapshot id is 6490 * provided. Snapshot mappings are always read-only. 6491 */ 6492 static int rbd_add_parse_args(const char *buf, 6493 struct ceph_options **ceph_opts, 6494 struct rbd_options **opts, 6495 struct rbd_spec **rbd_spec) 6496 { 6497 size_t len; 6498 char *options; 6499 const char *mon_addrs; 6500 char *snap_name; 6501 size_t mon_addrs_size; 6502 struct rbd_parse_opts_ctx pctx = { 0 }; 6503 int ret; 6504 6505 /* The first four tokens are required */ 6506 6507 len = next_token(&buf); 6508 if (!len) { 6509 rbd_warn(NULL, "no monitor address(es) provided"); 6510 return -EINVAL; 6511 } 6512 mon_addrs = buf; 6513 mon_addrs_size = len; 6514 buf += len; 6515 6516 ret = -EINVAL; 6517 options = dup_token(&buf, NULL); 6518 if (!options) 6519 return -ENOMEM; 6520 if (!*options) { 6521 rbd_warn(NULL, "no options provided"); 6522 goto out_err; 6523 } 6524 6525 pctx.spec = rbd_spec_alloc(); 6526 if (!pctx.spec) 6527 goto out_mem; 6528 6529 pctx.spec->pool_name = dup_token(&buf, NULL); 6530 if (!pctx.spec->pool_name) 6531 goto out_mem; 6532 if (!*pctx.spec->pool_name) { 6533 rbd_warn(NULL, "no pool name provided"); 6534 goto out_err; 6535 } 6536 6537 pctx.spec->image_name = dup_token(&buf, NULL); 6538 if (!pctx.spec->image_name) 6539 goto out_mem; 6540 if (!*pctx.spec->image_name) { 6541 rbd_warn(NULL, "no image name provided"); 6542 goto out_err; 6543 } 6544 6545 /* 6546 * Snapshot name is optional; default is to use "-" 6547 * (indicating the head/no snapshot). 6548 */ 6549 len = next_token(&buf); 6550 if (!len) { 6551 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */ 6552 len = sizeof (RBD_SNAP_HEAD_NAME) - 1; 6553 } else if (len > RBD_MAX_SNAP_NAME_LEN) { 6554 ret = -ENAMETOOLONG; 6555 goto out_err; 6556 } 6557 snap_name = kmemdup(buf, len + 1, GFP_KERNEL); 6558 if (!snap_name) 6559 goto out_mem; 6560 *(snap_name + len) = '\0'; 6561 pctx.spec->snap_name = snap_name; 6562 6563 pctx.copts = ceph_alloc_options(); 6564 if (!pctx.copts) 6565 goto out_mem; 6566 6567 /* Initialize all rbd options to the defaults */ 6568 6569 pctx.opts = kzalloc(sizeof(*pctx.opts), GFP_KERNEL); 6570 if (!pctx.opts) 6571 goto out_mem; 6572 6573 pctx.opts->read_only = RBD_READ_ONLY_DEFAULT; 6574 pctx.opts->queue_depth = RBD_QUEUE_DEPTH_DEFAULT; 6575 pctx.opts->alloc_size = RBD_ALLOC_SIZE_DEFAULT; 6576 pctx.opts->lock_timeout = RBD_LOCK_TIMEOUT_DEFAULT; 6577 pctx.opts->lock_on_read = RBD_LOCK_ON_READ_DEFAULT; 6578 pctx.opts->exclusive = RBD_EXCLUSIVE_DEFAULT; 6579 pctx.opts->trim = RBD_TRIM_DEFAULT; 6580 6581 ret = ceph_parse_mon_ips(mon_addrs, mon_addrs_size, pctx.copts, NULL); 6582 if (ret) 6583 goto out_err; 6584 6585 ret = rbd_parse_options(options, &pctx); 6586 if (ret) 6587 goto out_err; 6588 6589 *ceph_opts = pctx.copts; 6590 *opts = pctx.opts; 6591 *rbd_spec = pctx.spec; 6592 kfree(options); 6593 return 0; 6594 6595 out_mem: 6596 ret = -ENOMEM; 6597 out_err: 6598 kfree(pctx.opts); 6599 ceph_destroy_options(pctx.copts); 6600 rbd_spec_put(pctx.spec); 6601 kfree(options); 6602 return ret; 6603 } 6604 6605 static void rbd_dev_image_unlock(struct rbd_device *rbd_dev) 6606 { 6607 down_write(&rbd_dev->lock_rwsem); 6608 if (__rbd_is_lock_owner(rbd_dev)) 6609 __rbd_release_lock(rbd_dev); 6610 up_write(&rbd_dev->lock_rwsem); 6611 } 6612 6613 /* 6614 * If the wait is interrupted, an error is returned even if the lock 6615 * was successfully acquired. rbd_dev_image_unlock() will release it 6616 * if needed. 6617 */ 6618 static int rbd_add_acquire_lock(struct rbd_device *rbd_dev) 6619 { 6620 long ret; 6621 6622 if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) { 6623 if (!rbd_dev->opts->exclusive && !rbd_dev->opts->lock_on_read) 6624 return 0; 6625 6626 rbd_warn(rbd_dev, "exclusive-lock feature is not enabled"); 6627 return -EINVAL; 6628 } 6629 6630 if (rbd_is_ro(rbd_dev)) 6631 return 0; 6632 6633 rbd_assert(!rbd_is_lock_owner(rbd_dev)); 6634 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0); 6635 ret = wait_for_completion_killable_timeout(&rbd_dev->acquire_wait, 6636 ceph_timeout_jiffies(rbd_dev->opts->lock_timeout)); 6637 if (ret > 0) { 6638 ret = rbd_dev->acquire_err; 6639 } else { 6640 cancel_delayed_work_sync(&rbd_dev->lock_dwork); 6641 if (!ret) 6642 ret = -ETIMEDOUT; 6643 } 6644 6645 if (ret) { 6646 rbd_warn(rbd_dev, "failed to acquire exclusive lock: %ld", ret); 6647 return ret; 6648 } 6649 6650 /* 6651 * The lock may have been released by now, unless automatic lock 6652 * transitions are disabled. 6653 */ 6654 rbd_assert(!rbd_dev->opts->exclusive || rbd_is_lock_owner(rbd_dev)); 6655 return 0; 6656 } 6657 6658 /* 6659 * An rbd format 2 image has a unique identifier, distinct from the 6660 * name given to it by the user. Internally, that identifier is 6661 * what's used to specify the names of objects related to the image. 6662 * 6663 * A special "rbd id" object is used to map an rbd image name to its 6664 * id. If that object doesn't exist, then there is no v2 rbd image 6665 * with the supplied name. 6666 * 6667 * This function will record the given rbd_dev's image_id field if 6668 * it can be determined, and in that case will return 0. If any 6669 * errors occur a negative errno will be returned and the rbd_dev's 6670 * image_id field will be unchanged (and should be NULL). 6671 */ 6672 static int rbd_dev_image_id(struct rbd_device *rbd_dev) 6673 { 6674 int ret; 6675 size_t size; 6676 CEPH_DEFINE_OID_ONSTACK(oid); 6677 void *response; 6678 char *image_id; 6679 6680 /* 6681 * When probing a parent image, the image id is already 6682 * known (and the image name likely is not). There's no 6683 * need to fetch the image id again in this case. We 6684 * do still need to set the image format though. 6685 */ 6686 if (rbd_dev->spec->image_id) { 6687 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1; 6688 6689 return 0; 6690 } 6691 6692 /* 6693 * First, see if the format 2 image id file exists, and if 6694 * so, get the image's persistent id from it. 6695 */ 6696 ret = ceph_oid_aprintf(&oid, GFP_KERNEL, "%s%s", RBD_ID_PREFIX, 6697 rbd_dev->spec->image_name); 6698 if (ret) 6699 return ret; 6700 6701 dout("rbd id object name is %s\n", oid.name); 6702 6703 /* Response will be an encoded string, which includes a length */ 6704 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX; 6705 response = kzalloc(size, GFP_NOIO); 6706 if (!response) { 6707 ret = -ENOMEM; 6708 goto out; 6709 } 6710 6711 /* If it doesn't exist we'll assume it's a format 1 image */ 6712 6713 ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc, 6714 "get_id", NULL, 0, 6715 response, size); 6716 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 6717 if (ret == -ENOENT) { 6718 image_id = kstrdup("", GFP_KERNEL); 6719 ret = image_id ? 0 : -ENOMEM; 6720 if (!ret) 6721 rbd_dev->image_format = 1; 6722 } else if (ret >= 0) { 6723 void *p = response; 6724 6725 image_id = ceph_extract_encoded_string(&p, p + ret, 6726 NULL, GFP_NOIO); 6727 ret = PTR_ERR_OR_ZERO(image_id); 6728 if (!ret) 6729 rbd_dev->image_format = 2; 6730 } 6731 6732 if (!ret) { 6733 rbd_dev->spec->image_id = image_id; 6734 dout("image_id is %s\n", image_id); 6735 } 6736 out: 6737 kfree(response); 6738 ceph_oid_destroy(&oid); 6739 return ret; 6740 } 6741 6742 /* 6743 * Undo whatever state changes are made by v1 or v2 header info 6744 * call. 6745 */ 6746 static void rbd_dev_unprobe(struct rbd_device *rbd_dev) 6747 { 6748 struct rbd_image_header *header; 6749 6750 rbd_dev_parent_put(rbd_dev); 6751 rbd_object_map_free(rbd_dev); 6752 rbd_dev_mapping_clear(rbd_dev); 6753 6754 /* Free dynamic fields from the header, then zero it out */ 6755 6756 header = &rbd_dev->header; 6757 ceph_put_snap_context(header->snapc); 6758 kfree(header->snap_sizes); 6759 kfree(header->snap_names); 6760 kfree(header->object_prefix); 6761 memset(header, 0, sizeof (*header)); 6762 } 6763 6764 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev) 6765 { 6766 int ret; 6767 6768 ret = rbd_dev_v2_object_prefix(rbd_dev); 6769 if (ret) 6770 goto out_err; 6771 6772 /* 6773 * Get the and check features for the image. Currently the 6774 * features are assumed to never change. 6775 */ 6776 ret = rbd_dev_v2_features(rbd_dev); 6777 if (ret) 6778 goto out_err; 6779 6780 /* If the image supports fancy striping, get its parameters */ 6781 6782 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) { 6783 ret = rbd_dev_v2_striping_info(rbd_dev); 6784 if (ret < 0) 6785 goto out_err; 6786 } 6787 6788 if (rbd_dev->header.features & RBD_FEATURE_DATA_POOL) { 6789 ret = rbd_dev_v2_data_pool(rbd_dev); 6790 if (ret) 6791 goto out_err; 6792 } 6793 6794 rbd_init_layout(rbd_dev); 6795 return 0; 6796 6797 out_err: 6798 rbd_dev->header.features = 0; 6799 kfree(rbd_dev->header.object_prefix); 6800 rbd_dev->header.object_prefix = NULL; 6801 return ret; 6802 } 6803 6804 /* 6805 * @depth is rbd_dev_image_probe() -> rbd_dev_probe_parent() -> 6806 * rbd_dev_image_probe() recursion depth, which means it's also the 6807 * length of the already discovered part of the parent chain. 6808 */ 6809 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev, int depth) 6810 { 6811 struct rbd_device *parent = NULL; 6812 int ret; 6813 6814 if (!rbd_dev->parent_spec) 6815 return 0; 6816 6817 if (++depth > RBD_MAX_PARENT_CHAIN_LEN) { 6818 pr_info("parent chain is too long (%d)\n", depth); 6819 ret = -EINVAL; 6820 goto out_err; 6821 } 6822 6823 parent = __rbd_dev_create(rbd_dev->rbd_client, rbd_dev->parent_spec); 6824 if (!parent) { 6825 ret = -ENOMEM; 6826 goto out_err; 6827 } 6828 6829 /* 6830 * Images related by parent/child relationships always share 6831 * rbd_client and spec/parent_spec, so bump their refcounts. 6832 */ 6833 __rbd_get_client(rbd_dev->rbd_client); 6834 rbd_spec_get(rbd_dev->parent_spec); 6835 6836 __set_bit(RBD_DEV_FLAG_READONLY, &parent->flags); 6837 6838 ret = rbd_dev_image_probe(parent, depth); 6839 if (ret < 0) 6840 goto out_err; 6841 6842 rbd_dev->parent = parent; 6843 atomic_set(&rbd_dev->parent_ref, 1); 6844 return 0; 6845 6846 out_err: 6847 rbd_dev_unparent(rbd_dev); 6848 rbd_dev_destroy(parent); 6849 return ret; 6850 } 6851 6852 static void rbd_dev_device_release(struct rbd_device *rbd_dev) 6853 { 6854 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); 6855 rbd_free_disk(rbd_dev); 6856 if (!single_major) 6857 unregister_blkdev(rbd_dev->major, rbd_dev->name); 6858 } 6859 6860 /* 6861 * rbd_dev->header_rwsem must be locked for write and will be unlocked 6862 * upon return. 6863 */ 6864 static int rbd_dev_device_setup(struct rbd_device *rbd_dev) 6865 { 6866 int ret; 6867 6868 /* Record our major and minor device numbers. */ 6869 6870 if (!single_major) { 6871 ret = register_blkdev(0, rbd_dev->name); 6872 if (ret < 0) 6873 goto err_out_unlock; 6874 6875 rbd_dev->major = ret; 6876 rbd_dev->minor = 0; 6877 } else { 6878 rbd_dev->major = rbd_major; 6879 rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id); 6880 } 6881 6882 /* Set up the blkdev mapping. */ 6883 6884 ret = rbd_init_disk(rbd_dev); 6885 if (ret) 6886 goto err_out_blkdev; 6887 6888 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE); 6889 set_disk_ro(rbd_dev->disk, rbd_is_ro(rbd_dev)); 6890 6891 ret = dev_set_name(&rbd_dev->dev, "%d", rbd_dev->dev_id); 6892 if (ret) 6893 goto err_out_disk; 6894 6895 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); 6896 up_write(&rbd_dev->header_rwsem); 6897 return 0; 6898 6899 err_out_disk: 6900 rbd_free_disk(rbd_dev); 6901 err_out_blkdev: 6902 if (!single_major) 6903 unregister_blkdev(rbd_dev->major, rbd_dev->name); 6904 err_out_unlock: 6905 up_write(&rbd_dev->header_rwsem); 6906 return ret; 6907 } 6908 6909 static int rbd_dev_header_name(struct rbd_device *rbd_dev) 6910 { 6911 struct rbd_spec *spec = rbd_dev->spec; 6912 int ret; 6913 6914 /* Record the header object name for this rbd image. */ 6915 6916 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 6917 if (rbd_dev->image_format == 1) 6918 ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s", 6919 spec->image_name, RBD_SUFFIX); 6920 else 6921 ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s", 6922 RBD_HEADER_PREFIX, spec->image_id); 6923 6924 return ret; 6925 } 6926 6927 static void rbd_print_dne(struct rbd_device *rbd_dev, bool is_snap) 6928 { 6929 if (!is_snap) { 6930 pr_info("image %s/%s%s%s does not exist\n", 6931 rbd_dev->spec->pool_name, 6932 rbd_dev->spec->pool_ns ?: "", 6933 rbd_dev->spec->pool_ns ? "/" : "", 6934 rbd_dev->spec->image_name); 6935 } else { 6936 pr_info("snap %s/%s%s%s@%s does not exist\n", 6937 rbd_dev->spec->pool_name, 6938 rbd_dev->spec->pool_ns ?: "", 6939 rbd_dev->spec->pool_ns ? "/" : "", 6940 rbd_dev->spec->image_name, 6941 rbd_dev->spec->snap_name); 6942 } 6943 } 6944 6945 static void rbd_dev_image_release(struct rbd_device *rbd_dev) 6946 { 6947 if (!rbd_is_ro(rbd_dev)) 6948 rbd_unregister_watch(rbd_dev); 6949 6950 rbd_dev_unprobe(rbd_dev); 6951 rbd_dev->image_format = 0; 6952 kfree(rbd_dev->spec->image_id); 6953 rbd_dev->spec->image_id = NULL; 6954 } 6955 6956 /* 6957 * Probe for the existence of the header object for the given rbd 6958 * device. If this image is the one being mapped (i.e., not a 6959 * parent), initiate a watch on its header object before using that 6960 * object to get detailed information about the rbd image. 6961 * 6962 * On success, returns with header_rwsem held for write if called 6963 * with @depth == 0. 6964 */ 6965 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth) 6966 { 6967 bool need_watch = !rbd_is_ro(rbd_dev); 6968 int ret; 6969 6970 /* 6971 * Get the id from the image id object. Unless there's an 6972 * error, rbd_dev->spec->image_id will be filled in with 6973 * a dynamically-allocated string, and rbd_dev->image_format 6974 * will be set to either 1 or 2. 6975 */ 6976 ret = rbd_dev_image_id(rbd_dev); 6977 if (ret) 6978 return ret; 6979 6980 ret = rbd_dev_header_name(rbd_dev); 6981 if (ret) 6982 goto err_out_format; 6983 6984 if (need_watch) { 6985 ret = rbd_register_watch(rbd_dev); 6986 if (ret) { 6987 if (ret == -ENOENT) 6988 rbd_print_dne(rbd_dev, false); 6989 goto err_out_format; 6990 } 6991 } 6992 6993 if (!depth) 6994 down_write(&rbd_dev->header_rwsem); 6995 6996 ret = rbd_dev_header_info(rbd_dev); 6997 if (ret) { 6998 if (ret == -ENOENT && !need_watch) 6999 rbd_print_dne(rbd_dev, false); 7000 goto err_out_probe; 7001 } 7002 7003 /* 7004 * If this image is the one being mapped, we have pool name and 7005 * id, image name and id, and snap name - need to fill snap id. 7006 * Otherwise this is a parent image, identified by pool, image 7007 * and snap ids - need to fill in names for those ids. 7008 */ 7009 if (!depth) 7010 ret = rbd_spec_fill_snap_id(rbd_dev); 7011 else 7012 ret = rbd_spec_fill_names(rbd_dev); 7013 if (ret) { 7014 if (ret == -ENOENT) 7015 rbd_print_dne(rbd_dev, true); 7016 goto err_out_probe; 7017 } 7018 7019 ret = rbd_dev_mapping_set(rbd_dev); 7020 if (ret) 7021 goto err_out_probe; 7022 7023 if (rbd_is_snap(rbd_dev) && 7024 (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)) { 7025 ret = rbd_object_map_load(rbd_dev); 7026 if (ret) 7027 goto err_out_probe; 7028 } 7029 7030 if (rbd_dev->header.features & RBD_FEATURE_LAYERING) { 7031 ret = rbd_dev_v2_parent_info(rbd_dev); 7032 if (ret) 7033 goto err_out_probe; 7034 } 7035 7036 ret = rbd_dev_probe_parent(rbd_dev, depth); 7037 if (ret) 7038 goto err_out_probe; 7039 7040 dout("discovered format %u image, header name is %s\n", 7041 rbd_dev->image_format, rbd_dev->header_oid.name); 7042 return 0; 7043 7044 err_out_probe: 7045 if (!depth) 7046 up_write(&rbd_dev->header_rwsem); 7047 if (need_watch) 7048 rbd_unregister_watch(rbd_dev); 7049 rbd_dev_unprobe(rbd_dev); 7050 err_out_format: 7051 rbd_dev->image_format = 0; 7052 kfree(rbd_dev->spec->image_id); 7053 rbd_dev->spec->image_id = NULL; 7054 return ret; 7055 } 7056 7057 static ssize_t do_rbd_add(struct bus_type *bus, 7058 const char *buf, 7059 size_t count) 7060 { 7061 struct rbd_device *rbd_dev = NULL; 7062 struct ceph_options *ceph_opts = NULL; 7063 struct rbd_options *rbd_opts = NULL; 7064 struct rbd_spec *spec = NULL; 7065 struct rbd_client *rbdc; 7066 int rc; 7067 7068 if (!capable(CAP_SYS_ADMIN)) 7069 return -EPERM; 7070 7071 if (!try_module_get(THIS_MODULE)) 7072 return -ENODEV; 7073 7074 /* parse add command */ 7075 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec); 7076 if (rc < 0) 7077 goto out; 7078 7079 rbdc = rbd_get_client(ceph_opts); 7080 if (IS_ERR(rbdc)) { 7081 rc = PTR_ERR(rbdc); 7082 goto err_out_args; 7083 } 7084 7085 /* pick the pool */ 7086 rc = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, spec->pool_name); 7087 if (rc < 0) { 7088 if (rc == -ENOENT) 7089 pr_info("pool %s does not exist\n", spec->pool_name); 7090 goto err_out_client; 7091 } 7092 spec->pool_id = (u64)rc; 7093 7094 rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts); 7095 if (!rbd_dev) { 7096 rc = -ENOMEM; 7097 goto err_out_client; 7098 } 7099 rbdc = NULL; /* rbd_dev now owns this */ 7100 spec = NULL; /* rbd_dev now owns this */ 7101 rbd_opts = NULL; /* rbd_dev now owns this */ 7102 7103 /* if we are mapping a snapshot it will be a read-only mapping */ 7104 if (rbd_dev->opts->read_only || 7105 strcmp(rbd_dev->spec->snap_name, RBD_SNAP_HEAD_NAME)) 7106 __set_bit(RBD_DEV_FLAG_READONLY, &rbd_dev->flags); 7107 7108 rbd_dev->config_info = kstrdup(buf, GFP_KERNEL); 7109 if (!rbd_dev->config_info) { 7110 rc = -ENOMEM; 7111 goto err_out_rbd_dev; 7112 } 7113 7114 rc = rbd_dev_image_probe(rbd_dev, 0); 7115 if (rc < 0) 7116 goto err_out_rbd_dev; 7117 7118 if (rbd_dev->opts->alloc_size > rbd_dev->layout.object_size) { 7119 rbd_warn(rbd_dev, "alloc_size adjusted to %u", 7120 rbd_dev->layout.object_size); 7121 rbd_dev->opts->alloc_size = rbd_dev->layout.object_size; 7122 } 7123 7124 rc = rbd_dev_device_setup(rbd_dev); 7125 if (rc) 7126 goto err_out_image_probe; 7127 7128 rc = rbd_add_acquire_lock(rbd_dev); 7129 if (rc) 7130 goto err_out_image_lock; 7131 7132 /* Everything's ready. Announce the disk to the world. */ 7133 7134 rc = device_add(&rbd_dev->dev); 7135 if (rc) 7136 goto err_out_image_lock; 7137 7138 device_add_disk(&rbd_dev->dev, rbd_dev->disk, NULL); 7139 /* see rbd_init_disk() */ 7140 blk_put_queue(rbd_dev->disk->queue); 7141 7142 spin_lock(&rbd_dev_list_lock); 7143 list_add_tail(&rbd_dev->node, &rbd_dev_list); 7144 spin_unlock(&rbd_dev_list_lock); 7145 7146 pr_info("%s: capacity %llu features 0x%llx\n", rbd_dev->disk->disk_name, 7147 (unsigned long long)get_capacity(rbd_dev->disk) << SECTOR_SHIFT, 7148 rbd_dev->header.features); 7149 rc = count; 7150 out: 7151 module_put(THIS_MODULE); 7152 return rc; 7153 7154 err_out_image_lock: 7155 rbd_dev_image_unlock(rbd_dev); 7156 rbd_dev_device_release(rbd_dev); 7157 err_out_image_probe: 7158 rbd_dev_image_release(rbd_dev); 7159 err_out_rbd_dev: 7160 rbd_dev_destroy(rbd_dev); 7161 err_out_client: 7162 rbd_put_client(rbdc); 7163 err_out_args: 7164 rbd_spec_put(spec); 7165 kfree(rbd_opts); 7166 goto out; 7167 } 7168 7169 static ssize_t add_store(struct bus_type *bus, const char *buf, size_t count) 7170 { 7171 if (single_major) 7172 return -EINVAL; 7173 7174 return do_rbd_add(bus, buf, count); 7175 } 7176 7177 static ssize_t add_single_major_store(struct bus_type *bus, const char *buf, 7178 size_t count) 7179 { 7180 return do_rbd_add(bus, buf, count); 7181 } 7182 7183 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev) 7184 { 7185 while (rbd_dev->parent) { 7186 struct rbd_device *first = rbd_dev; 7187 struct rbd_device *second = first->parent; 7188 struct rbd_device *third; 7189 7190 /* 7191 * Follow to the parent with no grandparent and 7192 * remove it. 7193 */ 7194 while (second && (third = second->parent)) { 7195 first = second; 7196 second = third; 7197 } 7198 rbd_assert(second); 7199 rbd_dev_image_release(second); 7200 rbd_dev_destroy(second); 7201 first->parent = NULL; 7202 first->parent_overlap = 0; 7203 7204 rbd_assert(first->parent_spec); 7205 rbd_spec_put(first->parent_spec); 7206 first->parent_spec = NULL; 7207 } 7208 } 7209 7210 static ssize_t do_rbd_remove(struct bus_type *bus, 7211 const char *buf, 7212 size_t count) 7213 { 7214 struct rbd_device *rbd_dev = NULL; 7215 struct list_head *tmp; 7216 int dev_id; 7217 char opt_buf[6]; 7218 bool force = false; 7219 int ret; 7220 7221 if (!capable(CAP_SYS_ADMIN)) 7222 return -EPERM; 7223 7224 dev_id = -1; 7225 opt_buf[0] = '\0'; 7226 sscanf(buf, "%d %5s", &dev_id, opt_buf); 7227 if (dev_id < 0) { 7228 pr_err("dev_id out of range\n"); 7229 return -EINVAL; 7230 } 7231 if (opt_buf[0] != '\0') { 7232 if (!strcmp(opt_buf, "force")) { 7233 force = true; 7234 } else { 7235 pr_err("bad remove option at '%s'\n", opt_buf); 7236 return -EINVAL; 7237 } 7238 } 7239 7240 ret = -ENOENT; 7241 spin_lock(&rbd_dev_list_lock); 7242 list_for_each(tmp, &rbd_dev_list) { 7243 rbd_dev = list_entry(tmp, struct rbd_device, node); 7244 if (rbd_dev->dev_id == dev_id) { 7245 ret = 0; 7246 break; 7247 } 7248 } 7249 if (!ret) { 7250 spin_lock_irq(&rbd_dev->lock); 7251 if (rbd_dev->open_count && !force) 7252 ret = -EBUSY; 7253 else if (test_and_set_bit(RBD_DEV_FLAG_REMOVING, 7254 &rbd_dev->flags)) 7255 ret = -EINPROGRESS; 7256 spin_unlock_irq(&rbd_dev->lock); 7257 } 7258 spin_unlock(&rbd_dev_list_lock); 7259 if (ret) 7260 return ret; 7261 7262 if (force) { 7263 /* 7264 * Prevent new IO from being queued and wait for existing 7265 * IO to complete/fail. 7266 */ 7267 blk_mq_freeze_queue(rbd_dev->disk->queue); 7268 blk_set_queue_dying(rbd_dev->disk->queue); 7269 } 7270 7271 del_gendisk(rbd_dev->disk); 7272 spin_lock(&rbd_dev_list_lock); 7273 list_del_init(&rbd_dev->node); 7274 spin_unlock(&rbd_dev_list_lock); 7275 device_del(&rbd_dev->dev); 7276 7277 rbd_dev_image_unlock(rbd_dev); 7278 rbd_dev_device_release(rbd_dev); 7279 rbd_dev_image_release(rbd_dev); 7280 rbd_dev_destroy(rbd_dev); 7281 return count; 7282 } 7283 7284 static ssize_t remove_store(struct bus_type *bus, const char *buf, size_t count) 7285 { 7286 if (single_major) 7287 return -EINVAL; 7288 7289 return do_rbd_remove(bus, buf, count); 7290 } 7291 7292 static ssize_t remove_single_major_store(struct bus_type *bus, const char *buf, 7293 size_t count) 7294 { 7295 return do_rbd_remove(bus, buf, count); 7296 } 7297 7298 /* 7299 * create control files in sysfs 7300 * /sys/bus/rbd/... 7301 */ 7302 static int __init rbd_sysfs_init(void) 7303 { 7304 int ret; 7305 7306 ret = device_register(&rbd_root_dev); 7307 if (ret < 0) 7308 return ret; 7309 7310 ret = bus_register(&rbd_bus_type); 7311 if (ret < 0) 7312 device_unregister(&rbd_root_dev); 7313 7314 return ret; 7315 } 7316 7317 static void __exit rbd_sysfs_cleanup(void) 7318 { 7319 bus_unregister(&rbd_bus_type); 7320 device_unregister(&rbd_root_dev); 7321 } 7322 7323 static int __init rbd_slab_init(void) 7324 { 7325 rbd_assert(!rbd_img_request_cache); 7326 rbd_img_request_cache = KMEM_CACHE(rbd_img_request, 0); 7327 if (!rbd_img_request_cache) 7328 return -ENOMEM; 7329 7330 rbd_assert(!rbd_obj_request_cache); 7331 rbd_obj_request_cache = KMEM_CACHE(rbd_obj_request, 0); 7332 if (!rbd_obj_request_cache) 7333 goto out_err; 7334 7335 return 0; 7336 7337 out_err: 7338 kmem_cache_destroy(rbd_img_request_cache); 7339 rbd_img_request_cache = NULL; 7340 return -ENOMEM; 7341 } 7342 7343 static void rbd_slab_exit(void) 7344 { 7345 rbd_assert(rbd_obj_request_cache); 7346 kmem_cache_destroy(rbd_obj_request_cache); 7347 rbd_obj_request_cache = NULL; 7348 7349 rbd_assert(rbd_img_request_cache); 7350 kmem_cache_destroy(rbd_img_request_cache); 7351 rbd_img_request_cache = NULL; 7352 } 7353 7354 static int __init rbd_init(void) 7355 { 7356 int rc; 7357 7358 if (!libceph_compatible(NULL)) { 7359 rbd_warn(NULL, "libceph incompatibility (quitting)"); 7360 return -EINVAL; 7361 } 7362 7363 rc = rbd_slab_init(); 7364 if (rc) 7365 return rc; 7366 7367 /* 7368 * The number of active work items is limited by the number of 7369 * rbd devices * queue depth, so leave @max_active at default. 7370 */ 7371 rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0); 7372 if (!rbd_wq) { 7373 rc = -ENOMEM; 7374 goto err_out_slab; 7375 } 7376 7377 if (single_major) { 7378 rbd_major = register_blkdev(0, RBD_DRV_NAME); 7379 if (rbd_major < 0) { 7380 rc = rbd_major; 7381 goto err_out_wq; 7382 } 7383 } 7384 7385 rc = rbd_sysfs_init(); 7386 if (rc) 7387 goto err_out_blkdev; 7388 7389 if (single_major) 7390 pr_info("loaded (major %d)\n", rbd_major); 7391 else 7392 pr_info("loaded\n"); 7393 7394 return 0; 7395 7396 err_out_blkdev: 7397 if (single_major) 7398 unregister_blkdev(rbd_major, RBD_DRV_NAME); 7399 err_out_wq: 7400 destroy_workqueue(rbd_wq); 7401 err_out_slab: 7402 rbd_slab_exit(); 7403 return rc; 7404 } 7405 7406 static void __exit rbd_exit(void) 7407 { 7408 ida_destroy(&rbd_dev_id_ida); 7409 rbd_sysfs_cleanup(); 7410 if (single_major) 7411 unregister_blkdev(rbd_major, RBD_DRV_NAME); 7412 destroy_workqueue(rbd_wq); 7413 rbd_slab_exit(); 7414 } 7415 7416 module_init(rbd_init); 7417 module_exit(rbd_exit); 7418 7419 MODULE_AUTHOR("Alex Elder <elder@inktank.com>"); 7420 MODULE_AUTHOR("Sage Weil <sage@newdream.net>"); 7421 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>"); 7422 /* following authorship retained from original osdblk.c */ 7423 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>"); 7424 7425 MODULE_DESCRIPTION("RADOS Block Device (RBD) driver"); 7426 MODULE_LICENSE("GPL"); 7427