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/decode.h> 35 #include <linux/parser.h> 36 #include <linux/bsearch.h> 37 38 #include <linux/kernel.h> 39 #include <linux/device.h> 40 #include <linux/module.h> 41 #include <linux/fs.h> 42 #include <linux/blkdev.h> 43 #include <linux/slab.h> 44 #include <linux/idr.h> 45 46 #include "rbd_types.h" 47 48 #define RBD_DEBUG /* Activate rbd_assert() calls */ 49 50 /* 51 * The basic unit of block I/O is a sector. It is interpreted in a 52 * number of contexts in Linux (blk, bio, genhd), but the default is 53 * universally 512 bytes. These symbols are just slightly more 54 * meaningful than the bare numbers they represent. 55 */ 56 #define SECTOR_SHIFT 9 57 #define SECTOR_SIZE (1ULL << SECTOR_SHIFT) 58 59 /* 60 * Increment the given counter and return its updated value. 61 * If the counter is already 0 it will not be incremented. 62 * If the counter is already at its maximum value returns 63 * -EINVAL without updating it. 64 */ 65 static int atomic_inc_return_safe(atomic_t *v) 66 { 67 unsigned int counter; 68 69 counter = (unsigned int)__atomic_add_unless(v, 1, 0); 70 if (counter <= (unsigned int)INT_MAX) 71 return (int)counter; 72 73 atomic_dec(v); 74 75 return -EINVAL; 76 } 77 78 /* Decrement the counter. Return the resulting value, or -EINVAL */ 79 static int atomic_dec_return_safe(atomic_t *v) 80 { 81 int counter; 82 83 counter = atomic_dec_return(v); 84 if (counter >= 0) 85 return counter; 86 87 atomic_inc(v); 88 89 return -EINVAL; 90 } 91 92 #define RBD_DRV_NAME "rbd" 93 94 #define RBD_MINORS_PER_MAJOR 256 95 #define RBD_SINGLE_MAJOR_PART_SHIFT 4 96 97 #define RBD_SNAP_DEV_NAME_PREFIX "snap_" 98 #define RBD_MAX_SNAP_NAME_LEN \ 99 (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1)) 100 101 #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */ 102 103 #define RBD_SNAP_HEAD_NAME "-" 104 105 #define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */ 106 107 /* This allows a single page to hold an image name sent by OSD */ 108 #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1) 109 #define RBD_IMAGE_ID_LEN_MAX 64 110 111 #define RBD_OBJ_PREFIX_LEN_MAX 64 112 113 /* Feature bits */ 114 115 #define RBD_FEATURE_LAYERING (1<<0) 116 #define RBD_FEATURE_STRIPINGV2 (1<<1) 117 #define RBD_FEATURES_ALL \ 118 (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2) 119 120 /* Features supported by this (client software) implementation. */ 121 122 #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL) 123 124 /* 125 * An RBD device name will be "rbd#", where the "rbd" comes from 126 * RBD_DRV_NAME above, and # is a unique integer identifier. 127 * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big 128 * enough to hold all possible device names. 129 */ 130 #define DEV_NAME_LEN 32 131 #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1) 132 133 /* 134 * block device image metadata (in-memory version) 135 */ 136 struct rbd_image_header { 137 /* These six fields never change for a given rbd image */ 138 char *object_prefix; 139 __u8 obj_order; 140 __u8 crypt_type; 141 __u8 comp_type; 142 u64 stripe_unit; 143 u64 stripe_count; 144 u64 features; /* Might be changeable someday? */ 145 146 /* The remaining fields need to be updated occasionally */ 147 u64 image_size; 148 struct ceph_snap_context *snapc; 149 char *snap_names; /* format 1 only */ 150 u64 *snap_sizes; /* format 1 only */ 151 }; 152 153 /* 154 * An rbd image specification. 155 * 156 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely 157 * identify an image. Each rbd_dev structure includes a pointer to 158 * an rbd_spec structure that encapsulates this identity. 159 * 160 * Each of the id's in an rbd_spec has an associated name. For a 161 * user-mapped image, the names are supplied and the id's associated 162 * with them are looked up. For a layered image, a parent image is 163 * defined by the tuple, and the names are looked up. 164 * 165 * An rbd_dev structure contains a parent_spec pointer which is 166 * non-null if the image it represents is a child in a layered 167 * image. This pointer will refer to the rbd_spec structure used 168 * by the parent rbd_dev for its own identity (i.e., the structure 169 * is shared between the parent and child). 170 * 171 * Since these structures are populated once, during the discovery 172 * phase of image construction, they are effectively immutable so 173 * we make no effort to synchronize access to them. 174 * 175 * Note that code herein does not assume the image name is known (it 176 * could be a null pointer). 177 */ 178 struct rbd_spec { 179 u64 pool_id; 180 const char *pool_name; 181 182 const char *image_id; 183 const char *image_name; 184 185 u64 snap_id; 186 const char *snap_name; 187 188 struct kref kref; 189 }; 190 191 /* 192 * an instance of the client. multiple devices may share an rbd client. 193 */ 194 struct rbd_client { 195 struct ceph_client *client; 196 struct kref kref; 197 struct list_head node; 198 }; 199 200 struct rbd_img_request; 201 typedef void (*rbd_img_callback_t)(struct rbd_img_request *); 202 203 #define BAD_WHICH U32_MAX /* Good which or bad which, which? */ 204 205 struct rbd_obj_request; 206 typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *); 207 208 enum obj_request_type { 209 OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES 210 }; 211 212 enum obj_req_flags { 213 OBJ_REQ_DONE, /* completion flag: not done = 0, done = 1 */ 214 OBJ_REQ_IMG_DATA, /* object usage: standalone = 0, image = 1 */ 215 OBJ_REQ_KNOWN, /* EXISTS flag valid: no = 0, yes = 1 */ 216 OBJ_REQ_EXISTS, /* target exists: no = 0, yes = 1 */ 217 }; 218 219 struct rbd_obj_request { 220 const char *object_name; 221 u64 offset; /* object start byte */ 222 u64 length; /* bytes from offset */ 223 unsigned long flags; 224 225 /* 226 * An object request associated with an image will have its 227 * img_data flag set; a standalone object request will not. 228 * 229 * A standalone object request will have which == BAD_WHICH 230 * and a null obj_request pointer. 231 * 232 * An object request initiated in support of a layered image 233 * object (to check for its existence before a write) will 234 * have which == BAD_WHICH and a non-null obj_request pointer. 235 * 236 * Finally, an object request for rbd image data will have 237 * which != BAD_WHICH, and will have a non-null img_request 238 * pointer. The value of which will be in the range 239 * 0..(img_request->obj_request_count-1). 240 */ 241 union { 242 struct rbd_obj_request *obj_request; /* STAT op */ 243 struct { 244 struct rbd_img_request *img_request; 245 u64 img_offset; 246 /* links for img_request->obj_requests list */ 247 struct list_head links; 248 }; 249 }; 250 u32 which; /* posn image request list */ 251 252 enum obj_request_type type; 253 union { 254 struct bio *bio_list; 255 struct { 256 struct page **pages; 257 u32 page_count; 258 }; 259 }; 260 struct page **copyup_pages; 261 u32 copyup_page_count; 262 263 struct ceph_osd_request *osd_req; 264 265 u64 xferred; /* bytes transferred */ 266 int result; 267 268 rbd_obj_callback_t callback; 269 struct completion completion; 270 271 struct kref kref; 272 }; 273 274 enum img_req_flags { 275 IMG_REQ_WRITE, /* I/O direction: read = 0, write = 1 */ 276 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */ 277 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */ 278 }; 279 280 struct rbd_img_request { 281 struct rbd_device *rbd_dev; 282 u64 offset; /* starting image byte offset */ 283 u64 length; /* byte count from offset */ 284 unsigned long flags; 285 union { 286 u64 snap_id; /* for reads */ 287 struct ceph_snap_context *snapc; /* for writes */ 288 }; 289 union { 290 struct request *rq; /* block request */ 291 struct rbd_obj_request *obj_request; /* obj req initiator */ 292 }; 293 struct page **copyup_pages; 294 u32 copyup_page_count; 295 spinlock_t completion_lock;/* protects next_completion */ 296 u32 next_completion; 297 rbd_img_callback_t callback; 298 u64 xferred;/* aggregate bytes transferred */ 299 int result; /* first nonzero obj_request result */ 300 301 u32 obj_request_count; 302 struct list_head obj_requests; /* rbd_obj_request structs */ 303 304 struct kref kref; 305 }; 306 307 #define for_each_obj_request(ireq, oreq) \ 308 list_for_each_entry(oreq, &(ireq)->obj_requests, links) 309 #define for_each_obj_request_from(ireq, oreq) \ 310 list_for_each_entry_from(oreq, &(ireq)->obj_requests, links) 311 #define for_each_obj_request_safe(ireq, oreq, n) \ 312 list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links) 313 314 struct rbd_mapping { 315 u64 size; 316 u64 features; 317 bool read_only; 318 }; 319 320 /* 321 * a single device 322 */ 323 struct rbd_device { 324 int dev_id; /* blkdev unique id */ 325 326 int major; /* blkdev assigned major */ 327 int minor; 328 struct gendisk *disk; /* blkdev's gendisk and rq */ 329 330 u32 image_format; /* Either 1 or 2 */ 331 struct rbd_client *rbd_client; 332 333 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */ 334 335 spinlock_t lock; /* queue, flags, open_count */ 336 337 struct rbd_image_header header; 338 unsigned long flags; /* possibly lock protected */ 339 struct rbd_spec *spec; 340 341 char *header_name; 342 343 struct ceph_file_layout layout; 344 345 struct ceph_osd_event *watch_event; 346 struct rbd_obj_request *watch_request; 347 348 struct rbd_spec *parent_spec; 349 u64 parent_overlap; 350 atomic_t parent_ref; 351 struct rbd_device *parent; 352 353 /* protects updating the header */ 354 struct rw_semaphore header_rwsem; 355 356 struct rbd_mapping mapping; 357 358 struct list_head node; 359 360 /* sysfs related */ 361 struct device dev; 362 unsigned long open_count; /* protected by lock */ 363 }; 364 365 /* 366 * Flag bits for rbd_dev->flags. If atomicity is required, 367 * rbd_dev->lock is used to protect access. 368 * 369 * Currently, only the "removing" flag (which is coupled with the 370 * "open_count" field) requires atomic access. 371 */ 372 enum rbd_dev_flags { 373 RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */ 374 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */ 375 }; 376 377 static DEFINE_MUTEX(client_mutex); /* Serialize client creation */ 378 379 static LIST_HEAD(rbd_dev_list); /* devices */ 380 static DEFINE_SPINLOCK(rbd_dev_list_lock); 381 382 static LIST_HEAD(rbd_client_list); /* clients */ 383 static DEFINE_SPINLOCK(rbd_client_list_lock); 384 385 /* Slab caches for frequently-allocated structures */ 386 387 static struct kmem_cache *rbd_img_request_cache; 388 static struct kmem_cache *rbd_obj_request_cache; 389 static struct kmem_cache *rbd_segment_name_cache; 390 391 static int rbd_major; 392 static DEFINE_IDA(rbd_dev_id_ida); 393 394 /* 395 * Default to false for now, as single-major requires >= 0.75 version of 396 * userspace rbd utility. 397 */ 398 static bool single_major = false; 399 module_param(single_major, bool, S_IRUGO); 400 MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: false)"); 401 402 static int rbd_img_request_submit(struct rbd_img_request *img_request); 403 404 static void rbd_dev_device_release(struct device *dev); 405 406 static ssize_t rbd_add(struct bus_type *bus, const char *buf, 407 size_t count); 408 static ssize_t rbd_remove(struct bus_type *bus, const char *buf, 409 size_t count); 410 static ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf, 411 size_t count); 412 static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf, 413 size_t count); 414 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping); 415 static void rbd_spec_put(struct rbd_spec *spec); 416 417 static int rbd_dev_id_to_minor(int dev_id) 418 { 419 return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT; 420 } 421 422 static int minor_to_rbd_dev_id(int minor) 423 { 424 return minor >> RBD_SINGLE_MAJOR_PART_SHIFT; 425 } 426 427 static BUS_ATTR(add, S_IWUSR, NULL, rbd_add); 428 static BUS_ATTR(remove, S_IWUSR, NULL, rbd_remove); 429 static BUS_ATTR(add_single_major, S_IWUSR, NULL, rbd_add_single_major); 430 static BUS_ATTR(remove_single_major, S_IWUSR, NULL, rbd_remove_single_major); 431 432 static struct attribute *rbd_bus_attrs[] = { 433 &bus_attr_add.attr, 434 &bus_attr_remove.attr, 435 &bus_attr_add_single_major.attr, 436 &bus_attr_remove_single_major.attr, 437 NULL, 438 }; 439 440 static umode_t rbd_bus_is_visible(struct kobject *kobj, 441 struct attribute *attr, int index) 442 { 443 if (!single_major && 444 (attr == &bus_attr_add_single_major.attr || 445 attr == &bus_attr_remove_single_major.attr)) 446 return 0; 447 448 return attr->mode; 449 } 450 451 static const struct attribute_group rbd_bus_group = { 452 .attrs = rbd_bus_attrs, 453 .is_visible = rbd_bus_is_visible, 454 }; 455 __ATTRIBUTE_GROUPS(rbd_bus); 456 457 static struct bus_type rbd_bus_type = { 458 .name = "rbd", 459 .bus_groups = rbd_bus_groups, 460 }; 461 462 static void rbd_root_dev_release(struct device *dev) 463 { 464 } 465 466 static struct device rbd_root_dev = { 467 .init_name = "rbd", 468 .release = rbd_root_dev_release, 469 }; 470 471 static __printf(2, 3) 472 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...) 473 { 474 struct va_format vaf; 475 va_list args; 476 477 va_start(args, fmt); 478 vaf.fmt = fmt; 479 vaf.va = &args; 480 481 if (!rbd_dev) 482 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf); 483 else if (rbd_dev->disk) 484 printk(KERN_WARNING "%s: %s: %pV\n", 485 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf); 486 else if (rbd_dev->spec && rbd_dev->spec->image_name) 487 printk(KERN_WARNING "%s: image %s: %pV\n", 488 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf); 489 else if (rbd_dev->spec && rbd_dev->spec->image_id) 490 printk(KERN_WARNING "%s: id %s: %pV\n", 491 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf); 492 else /* punt */ 493 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n", 494 RBD_DRV_NAME, rbd_dev, &vaf); 495 va_end(args); 496 } 497 498 #ifdef RBD_DEBUG 499 #define rbd_assert(expr) \ 500 if (unlikely(!(expr))) { \ 501 printk(KERN_ERR "\nAssertion failure in %s() " \ 502 "at line %d:\n\n" \ 503 "\trbd_assert(%s);\n\n", \ 504 __func__, __LINE__, #expr); \ 505 BUG(); \ 506 } 507 #else /* !RBD_DEBUG */ 508 # define rbd_assert(expr) ((void) 0) 509 #endif /* !RBD_DEBUG */ 510 511 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request); 512 static void rbd_img_parent_read(struct rbd_obj_request *obj_request); 513 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev); 514 515 static int rbd_dev_refresh(struct rbd_device *rbd_dev); 516 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev); 517 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev); 518 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, 519 u64 snap_id); 520 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 521 u8 *order, u64 *snap_size); 522 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, 523 u64 *snap_features); 524 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name); 525 526 static int rbd_open(struct block_device *bdev, fmode_t mode) 527 { 528 struct rbd_device *rbd_dev = bdev->bd_disk->private_data; 529 bool removing = false; 530 531 if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only) 532 return -EROFS; 533 534 spin_lock_irq(&rbd_dev->lock); 535 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) 536 removing = true; 537 else 538 rbd_dev->open_count++; 539 spin_unlock_irq(&rbd_dev->lock); 540 if (removing) 541 return -ENOENT; 542 543 (void) get_device(&rbd_dev->dev); 544 545 return 0; 546 } 547 548 static void rbd_release(struct gendisk *disk, fmode_t mode) 549 { 550 struct rbd_device *rbd_dev = disk->private_data; 551 unsigned long open_count_before; 552 553 spin_lock_irq(&rbd_dev->lock); 554 open_count_before = rbd_dev->open_count--; 555 spin_unlock_irq(&rbd_dev->lock); 556 rbd_assert(open_count_before > 0); 557 558 put_device(&rbd_dev->dev); 559 } 560 561 static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg) 562 { 563 int ret = 0; 564 int val; 565 bool ro; 566 bool ro_changed = false; 567 568 /* get_user() may sleep, so call it before taking rbd_dev->lock */ 569 if (get_user(val, (int __user *)(arg))) 570 return -EFAULT; 571 572 ro = val ? true : false; 573 /* Snapshot doesn't allow to write*/ 574 if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro) 575 return -EROFS; 576 577 spin_lock_irq(&rbd_dev->lock); 578 /* prevent others open this device */ 579 if (rbd_dev->open_count > 1) { 580 ret = -EBUSY; 581 goto out; 582 } 583 584 if (rbd_dev->mapping.read_only != ro) { 585 rbd_dev->mapping.read_only = ro; 586 ro_changed = true; 587 } 588 589 out: 590 spin_unlock_irq(&rbd_dev->lock); 591 /* set_disk_ro() may sleep, so call it after releasing rbd_dev->lock */ 592 if (ret == 0 && ro_changed) 593 set_disk_ro(rbd_dev->disk, ro ? 1 : 0); 594 595 return ret; 596 } 597 598 static int rbd_ioctl(struct block_device *bdev, fmode_t mode, 599 unsigned int cmd, unsigned long arg) 600 { 601 struct rbd_device *rbd_dev = bdev->bd_disk->private_data; 602 int ret = 0; 603 604 switch (cmd) { 605 case BLKROSET: 606 ret = rbd_ioctl_set_ro(rbd_dev, arg); 607 break; 608 default: 609 ret = -ENOTTY; 610 } 611 612 return ret; 613 } 614 615 #ifdef CONFIG_COMPAT 616 static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode, 617 unsigned int cmd, unsigned long arg) 618 { 619 return rbd_ioctl(bdev, mode, cmd, arg); 620 } 621 #endif /* CONFIG_COMPAT */ 622 623 static const struct block_device_operations rbd_bd_ops = { 624 .owner = THIS_MODULE, 625 .open = rbd_open, 626 .release = rbd_release, 627 .ioctl = rbd_ioctl, 628 #ifdef CONFIG_COMPAT 629 .compat_ioctl = rbd_compat_ioctl, 630 #endif 631 }; 632 633 /* 634 * Initialize an rbd client instance. Success or not, this function 635 * consumes ceph_opts. Caller holds client_mutex. 636 */ 637 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts) 638 { 639 struct rbd_client *rbdc; 640 int ret = -ENOMEM; 641 642 dout("%s:\n", __func__); 643 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL); 644 if (!rbdc) 645 goto out_opt; 646 647 kref_init(&rbdc->kref); 648 INIT_LIST_HEAD(&rbdc->node); 649 650 rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0); 651 if (IS_ERR(rbdc->client)) 652 goto out_rbdc; 653 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */ 654 655 ret = ceph_open_session(rbdc->client); 656 if (ret < 0) 657 goto out_client; 658 659 spin_lock(&rbd_client_list_lock); 660 list_add_tail(&rbdc->node, &rbd_client_list); 661 spin_unlock(&rbd_client_list_lock); 662 663 dout("%s: rbdc %p\n", __func__, rbdc); 664 665 return rbdc; 666 out_client: 667 ceph_destroy_client(rbdc->client); 668 out_rbdc: 669 kfree(rbdc); 670 out_opt: 671 if (ceph_opts) 672 ceph_destroy_options(ceph_opts); 673 dout("%s: error %d\n", __func__, ret); 674 675 return ERR_PTR(ret); 676 } 677 678 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc) 679 { 680 kref_get(&rbdc->kref); 681 682 return rbdc; 683 } 684 685 /* 686 * Find a ceph client with specific addr and configuration. If 687 * found, bump its reference count. 688 */ 689 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts) 690 { 691 struct rbd_client *client_node; 692 bool found = false; 693 694 if (ceph_opts->flags & CEPH_OPT_NOSHARE) 695 return NULL; 696 697 spin_lock(&rbd_client_list_lock); 698 list_for_each_entry(client_node, &rbd_client_list, node) { 699 if (!ceph_compare_options(ceph_opts, client_node->client)) { 700 __rbd_get_client(client_node); 701 702 found = true; 703 break; 704 } 705 } 706 spin_unlock(&rbd_client_list_lock); 707 708 return found ? client_node : NULL; 709 } 710 711 /* 712 * mount options 713 */ 714 enum { 715 Opt_last_int, 716 /* int args above */ 717 Opt_last_string, 718 /* string args above */ 719 Opt_read_only, 720 Opt_read_write, 721 /* Boolean args above */ 722 Opt_last_bool, 723 }; 724 725 static match_table_t rbd_opts_tokens = { 726 /* int args above */ 727 /* string args above */ 728 {Opt_read_only, "read_only"}, 729 {Opt_read_only, "ro"}, /* Alternate spelling */ 730 {Opt_read_write, "read_write"}, 731 {Opt_read_write, "rw"}, /* Alternate spelling */ 732 /* Boolean args above */ 733 {-1, NULL} 734 }; 735 736 struct rbd_options { 737 bool read_only; 738 }; 739 740 #define RBD_READ_ONLY_DEFAULT false 741 742 static int parse_rbd_opts_token(char *c, void *private) 743 { 744 struct rbd_options *rbd_opts = private; 745 substring_t argstr[MAX_OPT_ARGS]; 746 int token, intval, ret; 747 748 token = match_token(c, rbd_opts_tokens, argstr); 749 if (token < 0) 750 return -EINVAL; 751 752 if (token < Opt_last_int) { 753 ret = match_int(&argstr[0], &intval); 754 if (ret < 0) { 755 pr_err("bad mount option arg (not int) " 756 "at '%s'\n", c); 757 return ret; 758 } 759 dout("got int token %d val %d\n", token, intval); 760 } else if (token > Opt_last_int && token < Opt_last_string) { 761 dout("got string token %d val %s\n", token, 762 argstr[0].from); 763 } else if (token > Opt_last_string && token < Opt_last_bool) { 764 dout("got Boolean token %d\n", token); 765 } else { 766 dout("got token %d\n", token); 767 } 768 769 switch (token) { 770 case Opt_read_only: 771 rbd_opts->read_only = true; 772 break; 773 case Opt_read_write: 774 rbd_opts->read_only = false; 775 break; 776 default: 777 rbd_assert(false); 778 break; 779 } 780 return 0; 781 } 782 783 /* 784 * Get a ceph client with specific addr and configuration, if one does 785 * not exist create it. Either way, ceph_opts is consumed by this 786 * function. 787 */ 788 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts) 789 { 790 struct rbd_client *rbdc; 791 792 mutex_lock_nested(&client_mutex, SINGLE_DEPTH_NESTING); 793 rbdc = rbd_client_find(ceph_opts); 794 if (rbdc) /* using an existing client */ 795 ceph_destroy_options(ceph_opts); 796 else 797 rbdc = rbd_client_create(ceph_opts); 798 mutex_unlock(&client_mutex); 799 800 return rbdc; 801 } 802 803 /* 804 * Destroy ceph client 805 * 806 * Caller must hold rbd_client_list_lock. 807 */ 808 static void rbd_client_release(struct kref *kref) 809 { 810 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref); 811 812 dout("%s: rbdc %p\n", __func__, rbdc); 813 spin_lock(&rbd_client_list_lock); 814 list_del(&rbdc->node); 815 spin_unlock(&rbd_client_list_lock); 816 817 ceph_destroy_client(rbdc->client); 818 kfree(rbdc); 819 } 820 821 /* 822 * Drop reference to ceph client node. If it's not referenced anymore, release 823 * it. 824 */ 825 static void rbd_put_client(struct rbd_client *rbdc) 826 { 827 if (rbdc) 828 kref_put(&rbdc->kref, rbd_client_release); 829 } 830 831 static bool rbd_image_format_valid(u32 image_format) 832 { 833 return image_format == 1 || image_format == 2; 834 } 835 836 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk) 837 { 838 size_t size; 839 u32 snap_count; 840 841 /* The header has to start with the magic rbd header text */ 842 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT))) 843 return false; 844 845 /* The bio layer requires at least sector-sized I/O */ 846 847 if (ondisk->options.order < SECTOR_SHIFT) 848 return false; 849 850 /* If we use u64 in a few spots we may be able to loosen this */ 851 852 if (ondisk->options.order > 8 * sizeof (int) - 1) 853 return false; 854 855 /* 856 * The size of a snapshot header has to fit in a size_t, and 857 * that limits the number of snapshots. 858 */ 859 snap_count = le32_to_cpu(ondisk->snap_count); 860 size = SIZE_MAX - sizeof (struct ceph_snap_context); 861 if (snap_count > size / sizeof (__le64)) 862 return false; 863 864 /* 865 * Not only that, but the size of the entire the snapshot 866 * header must also be representable in a size_t. 867 */ 868 size -= snap_count * sizeof (__le64); 869 if ((u64) size < le64_to_cpu(ondisk->snap_names_len)) 870 return false; 871 872 return true; 873 } 874 875 /* 876 * Fill an rbd image header with information from the given format 1 877 * on-disk header. 878 */ 879 static int rbd_header_from_disk(struct rbd_device *rbd_dev, 880 struct rbd_image_header_ondisk *ondisk) 881 { 882 struct rbd_image_header *header = &rbd_dev->header; 883 bool first_time = header->object_prefix == NULL; 884 struct ceph_snap_context *snapc; 885 char *object_prefix = NULL; 886 char *snap_names = NULL; 887 u64 *snap_sizes = NULL; 888 u32 snap_count; 889 size_t size; 890 int ret = -ENOMEM; 891 u32 i; 892 893 /* Allocate this now to avoid having to handle failure below */ 894 895 if (first_time) { 896 size_t len; 897 898 len = strnlen(ondisk->object_prefix, 899 sizeof (ondisk->object_prefix)); 900 object_prefix = kmalloc(len + 1, GFP_KERNEL); 901 if (!object_prefix) 902 return -ENOMEM; 903 memcpy(object_prefix, ondisk->object_prefix, len); 904 object_prefix[len] = '\0'; 905 } 906 907 /* Allocate the snapshot context and fill it in */ 908 909 snap_count = le32_to_cpu(ondisk->snap_count); 910 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); 911 if (!snapc) 912 goto out_err; 913 snapc->seq = le64_to_cpu(ondisk->snap_seq); 914 if (snap_count) { 915 struct rbd_image_snap_ondisk *snaps; 916 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len); 917 918 /* We'll keep a copy of the snapshot names... */ 919 920 if (snap_names_len > (u64)SIZE_MAX) 921 goto out_2big; 922 snap_names = kmalloc(snap_names_len, GFP_KERNEL); 923 if (!snap_names) 924 goto out_err; 925 926 /* ...as well as the array of their sizes. */ 927 928 size = snap_count * sizeof (*header->snap_sizes); 929 snap_sizes = kmalloc(size, GFP_KERNEL); 930 if (!snap_sizes) 931 goto out_err; 932 933 /* 934 * Copy the names, and fill in each snapshot's id 935 * and size. 936 * 937 * Note that rbd_dev_v1_header_info() guarantees the 938 * ondisk buffer we're working with has 939 * snap_names_len bytes beyond the end of the 940 * snapshot id array, this memcpy() is safe. 941 */ 942 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len); 943 snaps = ondisk->snaps; 944 for (i = 0; i < snap_count; i++) { 945 snapc->snaps[i] = le64_to_cpu(snaps[i].id); 946 snap_sizes[i] = le64_to_cpu(snaps[i].image_size); 947 } 948 } 949 950 /* We won't fail any more, fill in the header */ 951 952 if (first_time) { 953 header->object_prefix = object_prefix; 954 header->obj_order = ondisk->options.order; 955 header->crypt_type = ondisk->options.crypt_type; 956 header->comp_type = ondisk->options.comp_type; 957 /* The rest aren't used for format 1 images */ 958 header->stripe_unit = 0; 959 header->stripe_count = 0; 960 header->features = 0; 961 } else { 962 ceph_put_snap_context(header->snapc); 963 kfree(header->snap_names); 964 kfree(header->snap_sizes); 965 } 966 967 /* The remaining fields always get updated (when we refresh) */ 968 969 header->image_size = le64_to_cpu(ondisk->image_size); 970 header->snapc = snapc; 971 header->snap_names = snap_names; 972 header->snap_sizes = snap_sizes; 973 974 /* Make sure mapping size is consistent with header info */ 975 976 if (rbd_dev->spec->snap_id == CEPH_NOSNAP || first_time) 977 if (rbd_dev->mapping.size != header->image_size) 978 rbd_dev->mapping.size = header->image_size; 979 980 return 0; 981 out_2big: 982 ret = -EIO; 983 out_err: 984 kfree(snap_sizes); 985 kfree(snap_names); 986 ceph_put_snap_context(snapc); 987 kfree(object_prefix); 988 989 return ret; 990 } 991 992 static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which) 993 { 994 const char *snap_name; 995 996 rbd_assert(which < rbd_dev->header.snapc->num_snaps); 997 998 /* Skip over names until we find the one we are looking for */ 999 1000 snap_name = rbd_dev->header.snap_names; 1001 while (which--) 1002 snap_name += strlen(snap_name) + 1; 1003 1004 return kstrdup(snap_name, GFP_KERNEL); 1005 } 1006 1007 /* 1008 * Snapshot id comparison function for use with qsort()/bsearch(). 1009 * Note that result is for snapshots in *descending* order. 1010 */ 1011 static int snapid_compare_reverse(const void *s1, const void *s2) 1012 { 1013 u64 snap_id1 = *(u64 *)s1; 1014 u64 snap_id2 = *(u64 *)s2; 1015 1016 if (snap_id1 < snap_id2) 1017 return 1; 1018 return snap_id1 == snap_id2 ? 0 : -1; 1019 } 1020 1021 /* 1022 * Search a snapshot context to see if the given snapshot id is 1023 * present. 1024 * 1025 * Returns the position of the snapshot id in the array if it's found, 1026 * or BAD_SNAP_INDEX otherwise. 1027 * 1028 * Note: The snapshot array is in kept sorted (by the osd) in 1029 * reverse order, highest snapshot id first. 1030 */ 1031 static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id) 1032 { 1033 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 1034 u64 *found; 1035 1036 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps, 1037 sizeof (snap_id), snapid_compare_reverse); 1038 1039 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX; 1040 } 1041 1042 static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, 1043 u64 snap_id) 1044 { 1045 u32 which; 1046 const char *snap_name; 1047 1048 which = rbd_dev_snap_index(rbd_dev, snap_id); 1049 if (which == BAD_SNAP_INDEX) 1050 return ERR_PTR(-ENOENT); 1051 1052 snap_name = _rbd_dev_v1_snap_name(rbd_dev, which); 1053 return snap_name ? snap_name : ERR_PTR(-ENOMEM); 1054 } 1055 1056 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id) 1057 { 1058 if (snap_id == CEPH_NOSNAP) 1059 return RBD_SNAP_HEAD_NAME; 1060 1061 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 1062 if (rbd_dev->image_format == 1) 1063 return rbd_dev_v1_snap_name(rbd_dev, snap_id); 1064 1065 return rbd_dev_v2_snap_name(rbd_dev, snap_id); 1066 } 1067 1068 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 1069 u64 *snap_size) 1070 { 1071 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 1072 if (snap_id == CEPH_NOSNAP) { 1073 *snap_size = rbd_dev->header.image_size; 1074 } else if (rbd_dev->image_format == 1) { 1075 u32 which; 1076 1077 which = rbd_dev_snap_index(rbd_dev, snap_id); 1078 if (which == BAD_SNAP_INDEX) 1079 return -ENOENT; 1080 1081 *snap_size = rbd_dev->header.snap_sizes[which]; 1082 } else { 1083 u64 size = 0; 1084 int ret; 1085 1086 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size); 1087 if (ret) 1088 return ret; 1089 1090 *snap_size = size; 1091 } 1092 return 0; 1093 } 1094 1095 static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id, 1096 u64 *snap_features) 1097 { 1098 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 1099 if (snap_id == CEPH_NOSNAP) { 1100 *snap_features = rbd_dev->header.features; 1101 } else if (rbd_dev->image_format == 1) { 1102 *snap_features = 0; /* No features for format 1 */ 1103 } else { 1104 u64 features = 0; 1105 int ret; 1106 1107 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features); 1108 if (ret) 1109 return ret; 1110 1111 *snap_features = features; 1112 } 1113 return 0; 1114 } 1115 1116 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev) 1117 { 1118 u64 snap_id = rbd_dev->spec->snap_id; 1119 u64 size = 0; 1120 u64 features = 0; 1121 int ret; 1122 1123 ret = rbd_snap_size(rbd_dev, snap_id, &size); 1124 if (ret) 1125 return ret; 1126 ret = rbd_snap_features(rbd_dev, snap_id, &features); 1127 if (ret) 1128 return ret; 1129 1130 rbd_dev->mapping.size = size; 1131 rbd_dev->mapping.features = features; 1132 1133 return 0; 1134 } 1135 1136 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev) 1137 { 1138 rbd_dev->mapping.size = 0; 1139 rbd_dev->mapping.features = 0; 1140 } 1141 1142 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset) 1143 { 1144 char *name; 1145 u64 segment; 1146 int ret; 1147 char *name_format; 1148 1149 name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO); 1150 if (!name) 1151 return NULL; 1152 segment = offset >> rbd_dev->header.obj_order; 1153 name_format = "%s.%012llx"; 1154 if (rbd_dev->image_format == 2) 1155 name_format = "%s.%016llx"; 1156 ret = snprintf(name, CEPH_MAX_OID_NAME_LEN + 1, name_format, 1157 rbd_dev->header.object_prefix, segment); 1158 if (ret < 0 || ret > CEPH_MAX_OID_NAME_LEN) { 1159 pr_err("error formatting segment name for #%llu (%d)\n", 1160 segment, ret); 1161 kfree(name); 1162 name = NULL; 1163 } 1164 1165 return name; 1166 } 1167 1168 static void rbd_segment_name_free(const char *name) 1169 { 1170 /* The explicit cast here is needed to drop the const qualifier */ 1171 1172 kmem_cache_free(rbd_segment_name_cache, (void *)name); 1173 } 1174 1175 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset) 1176 { 1177 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order; 1178 1179 return offset & (segment_size - 1); 1180 } 1181 1182 static u64 rbd_segment_length(struct rbd_device *rbd_dev, 1183 u64 offset, u64 length) 1184 { 1185 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order; 1186 1187 offset &= segment_size - 1; 1188 1189 rbd_assert(length <= U64_MAX - offset); 1190 if (offset + length > segment_size) 1191 length = segment_size - offset; 1192 1193 return length; 1194 } 1195 1196 /* 1197 * returns the size of an object in the image 1198 */ 1199 static u64 rbd_obj_bytes(struct rbd_image_header *header) 1200 { 1201 return 1 << header->obj_order; 1202 } 1203 1204 /* 1205 * bio helpers 1206 */ 1207 1208 static void bio_chain_put(struct bio *chain) 1209 { 1210 struct bio *tmp; 1211 1212 while (chain) { 1213 tmp = chain; 1214 chain = chain->bi_next; 1215 bio_put(tmp); 1216 } 1217 } 1218 1219 /* 1220 * zeros a bio chain, starting at specific offset 1221 */ 1222 static void zero_bio_chain(struct bio *chain, int start_ofs) 1223 { 1224 struct bio_vec bv; 1225 struct bvec_iter iter; 1226 unsigned long flags; 1227 void *buf; 1228 int pos = 0; 1229 1230 while (chain) { 1231 bio_for_each_segment(bv, chain, iter) { 1232 if (pos + bv.bv_len > start_ofs) { 1233 int remainder = max(start_ofs - pos, 0); 1234 buf = bvec_kmap_irq(&bv, &flags); 1235 memset(buf + remainder, 0, 1236 bv.bv_len - remainder); 1237 flush_dcache_page(bv.bv_page); 1238 bvec_kunmap_irq(buf, &flags); 1239 } 1240 pos += bv.bv_len; 1241 } 1242 1243 chain = chain->bi_next; 1244 } 1245 } 1246 1247 /* 1248 * similar to zero_bio_chain(), zeros data defined by a page array, 1249 * starting at the given byte offset from the start of the array and 1250 * continuing up to the given end offset. The pages array is 1251 * assumed to be big enough to hold all bytes up to the end. 1252 */ 1253 static void zero_pages(struct page **pages, u64 offset, u64 end) 1254 { 1255 struct page **page = &pages[offset >> PAGE_SHIFT]; 1256 1257 rbd_assert(end > offset); 1258 rbd_assert(end - offset <= (u64)SIZE_MAX); 1259 while (offset < end) { 1260 size_t page_offset; 1261 size_t length; 1262 unsigned long flags; 1263 void *kaddr; 1264 1265 page_offset = offset & ~PAGE_MASK; 1266 length = min_t(size_t, PAGE_SIZE - page_offset, end - offset); 1267 local_irq_save(flags); 1268 kaddr = kmap_atomic(*page); 1269 memset(kaddr + page_offset, 0, length); 1270 flush_dcache_page(*page); 1271 kunmap_atomic(kaddr); 1272 local_irq_restore(flags); 1273 1274 offset += length; 1275 page++; 1276 } 1277 } 1278 1279 /* 1280 * Clone a portion of a bio, starting at the given byte offset 1281 * and continuing for the number of bytes indicated. 1282 */ 1283 static struct bio *bio_clone_range(struct bio *bio_src, 1284 unsigned int offset, 1285 unsigned int len, 1286 gfp_t gfpmask) 1287 { 1288 struct bio *bio; 1289 1290 bio = bio_clone(bio_src, gfpmask); 1291 if (!bio) 1292 return NULL; /* ENOMEM */ 1293 1294 bio_advance(bio, offset); 1295 bio->bi_iter.bi_size = len; 1296 1297 return bio; 1298 } 1299 1300 /* 1301 * Clone a portion of a bio chain, starting at the given byte offset 1302 * into the first bio in the source chain and continuing for the 1303 * number of bytes indicated. The result is another bio chain of 1304 * exactly the given length, or a null pointer on error. 1305 * 1306 * The bio_src and offset parameters are both in-out. On entry they 1307 * refer to the first source bio and the offset into that bio where 1308 * the start of data to be cloned is located. 1309 * 1310 * On return, bio_src is updated to refer to the bio in the source 1311 * chain that contains first un-cloned byte, and *offset will 1312 * contain the offset of that byte within that bio. 1313 */ 1314 static struct bio *bio_chain_clone_range(struct bio **bio_src, 1315 unsigned int *offset, 1316 unsigned int len, 1317 gfp_t gfpmask) 1318 { 1319 struct bio *bi = *bio_src; 1320 unsigned int off = *offset; 1321 struct bio *chain = NULL; 1322 struct bio **end; 1323 1324 /* Build up a chain of clone bios up to the limit */ 1325 1326 if (!bi || off >= bi->bi_iter.bi_size || !len) 1327 return NULL; /* Nothing to clone */ 1328 1329 end = &chain; 1330 while (len) { 1331 unsigned int bi_size; 1332 struct bio *bio; 1333 1334 if (!bi) { 1335 rbd_warn(NULL, "bio_chain exhausted with %u left", len); 1336 goto out_err; /* EINVAL; ran out of bio's */ 1337 } 1338 bi_size = min_t(unsigned int, bi->bi_iter.bi_size - off, len); 1339 bio = bio_clone_range(bi, off, bi_size, gfpmask); 1340 if (!bio) 1341 goto out_err; /* ENOMEM */ 1342 1343 *end = bio; 1344 end = &bio->bi_next; 1345 1346 off += bi_size; 1347 if (off == bi->bi_iter.bi_size) { 1348 bi = bi->bi_next; 1349 off = 0; 1350 } 1351 len -= bi_size; 1352 } 1353 *bio_src = bi; 1354 *offset = off; 1355 1356 return chain; 1357 out_err: 1358 bio_chain_put(chain); 1359 1360 return NULL; 1361 } 1362 1363 /* 1364 * The default/initial value for all object request flags is 0. For 1365 * each flag, once its value is set to 1 it is never reset to 0 1366 * again. 1367 */ 1368 static void obj_request_img_data_set(struct rbd_obj_request *obj_request) 1369 { 1370 if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) { 1371 struct rbd_device *rbd_dev; 1372 1373 rbd_dev = obj_request->img_request->rbd_dev; 1374 rbd_warn(rbd_dev, "obj_request %p already marked img_data\n", 1375 obj_request); 1376 } 1377 } 1378 1379 static bool obj_request_img_data_test(struct rbd_obj_request *obj_request) 1380 { 1381 smp_mb(); 1382 return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0; 1383 } 1384 1385 static void obj_request_done_set(struct rbd_obj_request *obj_request) 1386 { 1387 if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) { 1388 struct rbd_device *rbd_dev = NULL; 1389 1390 if (obj_request_img_data_test(obj_request)) 1391 rbd_dev = obj_request->img_request->rbd_dev; 1392 rbd_warn(rbd_dev, "obj_request %p already marked done\n", 1393 obj_request); 1394 } 1395 } 1396 1397 static bool obj_request_done_test(struct rbd_obj_request *obj_request) 1398 { 1399 smp_mb(); 1400 return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0; 1401 } 1402 1403 /* 1404 * This sets the KNOWN flag after (possibly) setting the EXISTS 1405 * flag. The latter is set based on the "exists" value provided. 1406 * 1407 * Note that for our purposes once an object exists it never goes 1408 * away again. It's possible that the response from two existence 1409 * checks are separated by the creation of the target object, and 1410 * the first ("doesn't exist") response arrives *after* the second 1411 * ("does exist"). In that case we ignore the second one. 1412 */ 1413 static void obj_request_existence_set(struct rbd_obj_request *obj_request, 1414 bool exists) 1415 { 1416 if (exists) 1417 set_bit(OBJ_REQ_EXISTS, &obj_request->flags); 1418 set_bit(OBJ_REQ_KNOWN, &obj_request->flags); 1419 smp_mb(); 1420 } 1421 1422 static bool obj_request_known_test(struct rbd_obj_request *obj_request) 1423 { 1424 smp_mb(); 1425 return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0; 1426 } 1427 1428 static bool obj_request_exists_test(struct rbd_obj_request *obj_request) 1429 { 1430 smp_mb(); 1431 return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0; 1432 } 1433 1434 static bool obj_request_overlaps_parent(struct rbd_obj_request *obj_request) 1435 { 1436 struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev; 1437 1438 return obj_request->img_offset < 1439 round_up(rbd_dev->parent_overlap, rbd_obj_bytes(&rbd_dev->header)); 1440 } 1441 1442 static void rbd_obj_request_get(struct rbd_obj_request *obj_request) 1443 { 1444 dout("%s: obj %p (was %d)\n", __func__, obj_request, 1445 atomic_read(&obj_request->kref.refcount)); 1446 kref_get(&obj_request->kref); 1447 } 1448 1449 static void rbd_obj_request_destroy(struct kref *kref); 1450 static void rbd_obj_request_put(struct rbd_obj_request *obj_request) 1451 { 1452 rbd_assert(obj_request != NULL); 1453 dout("%s: obj %p (was %d)\n", __func__, obj_request, 1454 atomic_read(&obj_request->kref.refcount)); 1455 kref_put(&obj_request->kref, rbd_obj_request_destroy); 1456 } 1457 1458 static void rbd_img_request_get(struct rbd_img_request *img_request) 1459 { 1460 dout("%s: img %p (was %d)\n", __func__, img_request, 1461 atomic_read(&img_request->kref.refcount)); 1462 kref_get(&img_request->kref); 1463 } 1464 1465 static bool img_request_child_test(struct rbd_img_request *img_request); 1466 static void rbd_parent_request_destroy(struct kref *kref); 1467 static void rbd_img_request_destroy(struct kref *kref); 1468 static void rbd_img_request_put(struct rbd_img_request *img_request) 1469 { 1470 rbd_assert(img_request != NULL); 1471 dout("%s: img %p (was %d)\n", __func__, img_request, 1472 atomic_read(&img_request->kref.refcount)); 1473 if (img_request_child_test(img_request)) 1474 kref_put(&img_request->kref, rbd_parent_request_destroy); 1475 else 1476 kref_put(&img_request->kref, rbd_img_request_destroy); 1477 } 1478 1479 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request, 1480 struct rbd_obj_request *obj_request) 1481 { 1482 rbd_assert(obj_request->img_request == NULL); 1483 1484 /* Image request now owns object's original reference */ 1485 obj_request->img_request = img_request; 1486 obj_request->which = img_request->obj_request_count; 1487 rbd_assert(!obj_request_img_data_test(obj_request)); 1488 obj_request_img_data_set(obj_request); 1489 rbd_assert(obj_request->which != BAD_WHICH); 1490 img_request->obj_request_count++; 1491 list_add_tail(&obj_request->links, &img_request->obj_requests); 1492 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request, 1493 obj_request->which); 1494 } 1495 1496 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request, 1497 struct rbd_obj_request *obj_request) 1498 { 1499 rbd_assert(obj_request->which != BAD_WHICH); 1500 1501 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request, 1502 obj_request->which); 1503 list_del(&obj_request->links); 1504 rbd_assert(img_request->obj_request_count > 0); 1505 img_request->obj_request_count--; 1506 rbd_assert(obj_request->which == img_request->obj_request_count); 1507 obj_request->which = BAD_WHICH; 1508 rbd_assert(obj_request_img_data_test(obj_request)); 1509 rbd_assert(obj_request->img_request == img_request); 1510 obj_request->img_request = NULL; 1511 obj_request->callback = NULL; 1512 rbd_obj_request_put(obj_request); 1513 } 1514 1515 static bool obj_request_type_valid(enum obj_request_type type) 1516 { 1517 switch (type) { 1518 case OBJ_REQUEST_NODATA: 1519 case OBJ_REQUEST_BIO: 1520 case OBJ_REQUEST_PAGES: 1521 return true; 1522 default: 1523 return false; 1524 } 1525 } 1526 1527 static int rbd_obj_request_submit(struct ceph_osd_client *osdc, 1528 struct rbd_obj_request *obj_request) 1529 { 1530 dout("%s: osdc %p obj %p\n", __func__, osdc, obj_request); 1531 1532 return ceph_osdc_start_request(osdc, obj_request->osd_req, false); 1533 } 1534 1535 static void rbd_img_request_complete(struct rbd_img_request *img_request) 1536 { 1537 1538 dout("%s: img %p\n", __func__, img_request); 1539 1540 /* 1541 * If no error occurred, compute the aggregate transfer 1542 * count for the image request. We could instead use 1543 * atomic64_cmpxchg() to update it as each object request 1544 * completes; not clear which way is better off hand. 1545 */ 1546 if (!img_request->result) { 1547 struct rbd_obj_request *obj_request; 1548 u64 xferred = 0; 1549 1550 for_each_obj_request(img_request, obj_request) 1551 xferred += obj_request->xferred; 1552 img_request->xferred = xferred; 1553 } 1554 1555 if (img_request->callback) 1556 img_request->callback(img_request); 1557 else 1558 rbd_img_request_put(img_request); 1559 } 1560 1561 /* Caller is responsible for rbd_obj_request_destroy(obj_request) */ 1562 1563 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request) 1564 { 1565 dout("%s: obj %p\n", __func__, obj_request); 1566 1567 return wait_for_completion_interruptible(&obj_request->completion); 1568 } 1569 1570 /* 1571 * The default/initial value for all image request flags is 0. Each 1572 * is conditionally set to 1 at image request initialization time 1573 * and currently never change thereafter. 1574 */ 1575 static void img_request_write_set(struct rbd_img_request *img_request) 1576 { 1577 set_bit(IMG_REQ_WRITE, &img_request->flags); 1578 smp_mb(); 1579 } 1580 1581 static bool img_request_write_test(struct rbd_img_request *img_request) 1582 { 1583 smp_mb(); 1584 return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0; 1585 } 1586 1587 static void img_request_child_set(struct rbd_img_request *img_request) 1588 { 1589 set_bit(IMG_REQ_CHILD, &img_request->flags); 1590 smp_mb(); 1591 } 1592 1593 static void img_request_child_clear(struct rbd_img_request *img_request) 1594 { 1595 clear_bit(IMG_REQ_CHILD, &img_request->flags); 1596 smp_mb(); 1597 } 1598 1599 static bool img_request_child_test(struct rbd_img_request *img_request) 1600 { 1601 smp_mb(); 1602 return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0; 1603 } 1604 1605 static void img_request_layered_set(struct rbd_img_request *img_request) 1606 { 1607 set_bit(IMG_REQ_LAYERED, &img_request->flags); 1608 smp_mb(); 1609 } 1610 1611 static void img_request_layered_clear(struct rbd_img_request *img_request) 1612 { 1613 clear_bit(IMG_REQ_LAYERED, &img_request->flags); 1614 smp_mb(); 1615 } 1616 1617 static bool img_request_layered_test(struct rbd_img_request *img_request) 1618 { 1619 smp_mb(); 1620 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0; 1621 } 1622 1623 static void 1624 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request) 1625 { 1626 u64 xferred = obj_request->xferred; 1627 u64 length = obj_request->length; 1628 1629 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__, 1630 obj_request, obj_request->img_request, obj_request->result, 1631 xferred, length); 1632 /* 1633 * ENOENT means a hole in the image. We zero-fill the entire 1634 * length of the request. A short read also implies zero-fill 1635 * to the end of the request. An error requires the whole 1636 * length of the request to be reported finished with an error 1637 * to the block layer. In each case we update the xferred 1638 * count to indicate the whole request was satisfied. 1639 */ 1640 rbd_assert(obj_request->type != OBJ_REQUEST_NODATA); 1641 if (obj_request->result == -ENOENT) { 1642 if (obj_request->type == OBJ_REQUEST_BIO) 1643 zero_bio_chain(obj_request->bio_list, 0); 1644 else 1645 zero_pages(obj_request->pages, 0, length); 1646 obj_request->result = 0; 1647 } else if (xferred < length && !obj_request->result) { 1648 if (obj_request->type == OBJ_REQUEST_BIO) 1649 zero_bio_chain(obj_request->bio_list, xferred); 1650 else 1651 zero_pages(obj_request->pages, xferred, length); 1652 } 1653 obj_request->xferred = length; 1654 obj_request_done_set(obj_request); 1655 } 1656 1657 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request) 1658 { 1659 dout("%s: obj %p cb %p\n", __func__, obj_request, 1660 obj_request->callback); 1661 if (obj_request->callback) 1662 obj_request->callback(obj_request); 1663 else 1664 complete_all(&obj_request->completion); 1665 } 1666 1667 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request) 1668 { 1669 dout("%s: obj %p\n", __func__, obj_request); 1670 obj_request_done_set(obj_request); 1671 } 1672 1673 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request) 1674 { 1675 struct rbd_img_request *img_request = NULL; 1676 struct rbd_device *rbd_dev = NULL; 1677 bool layered = false; 1678 1679 if (obj_request_img_data_test(obj_request)) { 1680 img_request = obj_request->img_request; 1681 layered = img_request && img_request_layered_test(img_request); 1682 rbd_dev = img_request->rbd_dev; 1683 } 1684 1685 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__, 1686 obj_request, img_request, obj_request->result, 1687 obj_request->xferred, obj_request->length); 1688 if (layered && obj_request->result == -ENOENT && 1689 obj_request->img_offset < rbd_dev->parent_overlap) 1690 rbd_img_parent_read(obj_request); 1691 else if (img_request) 1692 rbd_img_obj_request_read_callback(obj_request); 1693 else 1694 obj_request_done_set(obj_request); 1695 } 1696 1697 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request) 1698 { 1699 dout("%s: obj %p result %d %llu\n", __func__, obj_request, 1700 obj_request->result, obj_request->length); 1701 /* 1702 * There is no such thing as a successful short write. Set 1703 * it to our originally-requested length. 1704 */ 1705 obj_request->xferred = obj_request->length; 1706 obj_request_done_set(obj_request); 1707 } 1708 1709 /* 1710 * For a simple stat call there's nothing to do. We'll do more if 1711 * this is part of a write sequence for a layered image. 1712 */ 1713 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request) 1714 { 1715 dout("%s: obj %p\n", __func__, obj_request); 1716 obj_request_done_set(obj_request); 1717 } 1718 1719 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req, 1720 struct ceph_msg *msg) 1721 { 1722 struct rbd_obj_request *obj_request = osd_req->r_priv; 1723 u16 opcode; 1724 1725 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg); 1726 rbd_assert(osd_req == obj_request->osd_req); 1727 if (obj_request_img_data_test(obj_request)) { 1728 rbd_assert(obj_request->img_request); 1729 rbd_assert(obj_request->which != BAD_WHICH); 1730 } else { 1731 rbd_assert(obj_request->which == BAD_WHICH); 1732 } 1733 1734 if (osd_req->r_result < 0) 1735 obj_request->result = osd_req->r_result; 1736 1737 rbd_assert(osd_req->r_num_ops <= CEPH_OSD_MAX_OP); 1738 1739 /* 1740 * We support a 64-bit length, but ultimately it has to be 1741 * passed to blk_end_request(), which takes an unsigned int. 1742 */ 1743 obj_request->xferred = osd_req->r_reply_op_len[0]; 1744 rbd_assert(obj_request->xferred < (u64)UINT_MAX); 1745 1746 opcode = osd_req->r_ops[0].op; 1747 switch (opcode) { 1748 case CEPH_OSD_OP_READ: 1749 rbd_osd_read_callback(obj_request); 1750 break; 1751 case CEPH_OSD_OP_SETALLOCHINT: 1752 rbd_assert(osd_req->r_ops[1].op == CEPH_OSD_OP_WRITE); 1753 /* fall through */ 1754 case CEPH_OSD_OP_WRITE: 1755 rbd_osd_write_callback(obj_request); 1756 break; 1757 case CEPH_OSD_OP_STAT: 1758 rbd_osd_stat_callback(obj_request); 1759 break; 1760 case CEPH_OSD_OP_CALL: 1761 case CEPH_OSD_OP_NOTIFY_ACK: 1762 case CEPH_OSD_OP_WATCH: 1763 rbd_osd_trivial_callback(obj_request); 1764 break; 1765 default: 1766 rbd_warn(NULL, "%s: unsupported op %hu\n", 1767 obj_request->object_name, (unsigned short) opcode); 1768 break; 1769 } 1770 1771 if (obj_request_done_test(obj_request)) 1772 rbd_obj_request_complete(obj_request); 1773 } 1774 1775 static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request) 1776 { 1777 struct rbd_img_request *img_request = obj_request->img_request; 1778 struct ceph_osd_request *osd_req = obj_request->osd_req; 1779 u64 snap_id; 1780 1781 rbd_assert(osd_req != NULL); 1782 1783 snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP; 1784 ceph_osdc_build_request(osd_req, obj_request->offset, 1785 NULL, snap_id, NULL); 1786 } 1787 1788 static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request) 1789 { 1790 struct rbd_img_request *img_request = obj_request->img_request; 1791 struct ceph_osd_request *osd_req = obj_request->osd_req; 1792 struct ceph_snap_context *snapc; 1793 struct timespec mtime = CURRENT_TIME; 1794 1795 rbd_assert(osd_req != NULL); 1796 1797 snapc = img_request ? img_request->snapc : NULL; 1798 ceph_osdc_build_request(osd_req, obj_request->offset, 1799 snapc, CEPH_NOSNAP, &mtime); 1800 } 1801 1802 /* 1803 * Create an osd request. A read request has one osd op (read). 1804 * A write request has either one (watch) or two (hint+write) osd ops. 1805 * (All rbd data writes are prefixed with an allocation hint op, but 1806 * technically osd watch is a write request, hence this distinction.) 1807 */ 1808 static struct ceph_osd_request *rbd_osd_req_create( 1809 struct rbd_device *rbd_dev, 1810 bool write_request, 1811 unsigned int num_ops, 1812 struct rbd_obj_request *obj_request) 1813 { 1814 struct ceph_snap_context *snapc = NULL; 1815 struct ceph_osd_client *osdc; 1816 struct ceph_osd_request *osd_req; 1817 1818 if (obj_request_img_data_test(obj_request)) { 1819 struct rbd_img_request *img_request = obj_request->img_request; 1820 1821 rbd_assert(write_request == 1822 img_request_write_test(img_request)); 1823 if (write_request) 1824 snapc = img_request->snapc; 1825 } 1826 1827 rbd_assert(num_ops == 1 || (write_request && num_ops == 2)); 1828 1829 /* Allocate and initialize the request, for the num_ops ops */ 1830 1831 osdc = &rbd_dev->rbd_client->client->osdc; 1832 osd_req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, 1833 GFP_ATOMIC); 1834 if (!osd_req) 1835 return NULL; /* ENOMEM */ 1836 1837 if (write_request) 1838 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK; 1839 else 1840 osd_req->r_flags = CEPH_OSD_FLAG_READ; 1841 1842 osd_req->r_callback = rbd_osd_req_callback; 1843 osd_req->r_priv = obj_request; 1844 1845 osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout); 1846 ceph_oid_set_name(&osd_req->r_base_oid, obj_request->object_name); 1847 1848 return osd_req; 1849 } 1850 1851 /* 1852 * Create a copyup osd request based on the information in the 1853 * object request supplied. A copyup request has three osd ops, 1854 * a copyup method call, a hint op, and a write op. 1855 */ 1856 static struct ceph_osd_request * 1857 rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request) 1858 { 1859 struct rbd_img_request *img_request; 1860 struct ceph_snap_context *snapc; 1861 struct rbd_device *rbd_dev; 1862 struct ceph_osd_client *osdc; 1863 struct ceph_osd_request *osd_req; 1864 1865 rbd_assert(obj_request_img_data_test(obj_request)); 1866 img_request = obj_request->img_request; 1867 rbd_assert(img_request); 1868 rbd_assert(img_request_write_test(img_request)); 1869 1870 /* Allocate and initialize the request, for the three ops */ 1871 1872 snapc = img_request->snapc; 1873 rbd_dev = img_request->rbd_dev; 1874 osdc = &rbd_dev->rbd_client->client->osdc; 1875 osd_req = ceph_osdc_alloc_request(osdc, snapc, 3, false, GFP_ATOMIC); 1876 if (!osd_req) 1877 return NULL; /* ENOMEM */ 1878 1879 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK; 1880 osd_req->r_callback = rbd_osd_req_callback; 1881 osd_req->r_priv = obj_request; 1882 1883 osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout); 1884 ceph_oid_set_name(&osd_req->r_base_oid, obj_request->object_name); 1885 1886 return osd_req; 1887 } 1888 1889 1890 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req) 1891 { 1892 ceph_osdc_put_request(osd_req); 1893 } 1894 1895 /* object_name is assumed to be a non-null pointer and NUL-terminated */ 1896 1897 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name, 1898 u64 offset, u64 length, 1899 enum obj_request_type type) 1900 { 1901 struct rbd_obj_request *obj_request; 1902 size_t size; 1903 char *name; 1904 1905 rbd_assert(obj_request_type_valid(type)); 1906 1907 size = strlen(object_name) + 1; 1908 name = kmalloc(size, GFP_KERNEL); 1909 if (!name) 1910 return NULL; 1911 1912 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_KERNEL); 1913 if (!obj_request) { 1914 kfree(name); 1915 return NULL; 1916 } 1917 1918 obj_request->object_name = memcpy(name, object_name, size); 1919 obj_request->offset = offset; 1920 obj_request->length = length; 1921 obj_request->flags = 0; 1922 obj_request->which = BAD_WHICH; 1923 obj_request->type = type; 1924 INIT_LIST_HEAD(&obj_request->links); 1925 init_completion(&obj_request->completion); 1926 kref_init(&obj_request->kref); 1927 1928 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name, 1929 offset, length, (int)type, obj_request); 1930 1931 return obj_request; 1932 } 1933 1934 static void rbd_obj_request_destroy(struct kref *kref) 1935 { 1936 struct rbd_obj_request *obj_request; 1937 1938 obj_request = container_of(kref, struct rbd_obj_request, kref); 1939 1940 dout("%s: obj %p\n", __func__, obj_request); 1941 1942 rbd_assert(obj_request->img_request == NULL); 1943 rbd_assert(obj_request->which == BAD_WHICH); 1944 1945 if (obj_request->osd_req) 1946 rbd_osd_req_destroy(obj_request->osd_req); 1947 1948 rbd_assert(obj_request_type_valid(obj_request->type)); 1949 switch (obj_request->type) { 1950 case OBJ_REQUEST_NODATA: 1951 break; /* Nothing to do */ 1952 case OBJ_REQUEST_BIO: 1953 if (obj_request->bio_list) 1954 bio_chain_put(obj_request->bio_list); 1955 break; 1956 case OBJ_REQUEST_PAGES: 1957 if (obj_request->pages) 1958 ceph_release_page_vector(obj_request->pages, 1959 obj_request->page_count); 1960 break; 1961 } 1962 1963 kfree(obj_request->object_name); 1964 obj_request->object_name = NULL; 1965 kmem_cache_free(rbd_obj_request_cache, obj_request); 1966 } 1967 1968 /* It's OK to call this for a device with no parent */ 1969 1970 static void rbd_spec_put(struct rbd_spec *spec); 1971 static void rbd_dev_unparent(struct rbd_device *rbd_dev) 1972 { 1973 rbd_dev_remove_parent(rbd_dev); 1974 rbd_spec_put(rbd_dev->parent_spec); 1975 rbd_dev->parent_spec = NULL; 1976 rbd_dev->parent_overlap = 0; 1977 } 1978 1979 /* 1980 * Parent image reference counting is used to determine when an 1981 * image's parent fields can be safely torn down--after there are no 1982 * more in-flight requests to the parent image. When the last 1983 * reference is dropped, cleaning them up is safe. 1984 */ 1985 static void rbd_dev_parent_put(struct rbd_device *rbd_dev) 1986 { 1987 int counter; 1988 1989 if (!rbd_dev->parent_spec) 1990 return; 1991 1992 counter = atomic_dec_return_safe(&rbd_dev->parent_ref); 1993 if (counter > 0) 1994 return; 1995 1996 /* Last reference; clean up parent data structures */ 1997 1998 if (!counter) 1999 rbd_dev_unparent(rbd_dev); 2000 else 2001 rbd_warn(rbd_dev, "parent reference underflow\n"); 2002 } 2003 2004 /* 2005 * If an image has a non-zero parent overlap, get a reference to its 2006 * parent. 2007 * 2008 * We must get the reference before checking for the overlap to 2009 * coordinate properly with zeroing the parent overlap in 2010 * rbd_dev_v2_parent_info() when an image gets flattened. We 2011 * drop it again if there is no overlap. 2012 * 2013 * Returns true if the rbd device has a parent with a non-zero 2014 * overlap and a reference for it was successfully taken, or 2015 * false otherwise. 2016 */ 2017 static bool rbd_dev_parent_get(struct rbd_device *rbd_dev) 2018 { 2019 int counter; 2020 2021 if (!rbd_dev->parent_spec) 2022 return false; 2023 2024 counter = atomic_inc_return_safe(&rbd_dev->parent_ref); 2025 if (counter > 0 && rbd_dev->parent_overlap) 2026 return true; 2027 2028 /* Image was flattened, but parent is not yet torn down */ 2029 2030 if (counter < 0) 2031 rbd_warn(rbd_dev, "parent reference overflow\n"); 2032 2033 return false; 2034 } 2035 2036 /* 2037 * Caller is responsible for filling in the list of object requests 2038 * that comprises the image request, and the Linux request pointer 2039 * (if there is one). 2040 */ 2041 static struct rbd_img_request *rbd_img_request_create( 2042 struct rbd_device *rbd_dev, 2043 u64 offset, u64 length, 2044 bool write_request) 2045 { 2046 struct rbd_img_request *img_request; 2047 2048 img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_ATOMIC); 2049 if (!img_request) 2050 return NULL; 2051 2052 if (write_request) { 2053 down_read(&rbd_dev->header_rwsem); 2054 ceph_get_snap_context(rbd_dev->header.snapc); 2055 up_read(&rbd_dev->header_rwsem); 2056 } 2057 2058 img_request->rq = NULL; 2059 img_request->rbd_dev = rbd_dev; 2060 img_request->offset = offset; 2061 img_request->length = length; 2062 img_request->flags = 0; 2063 if (write_request) { 2064 img_request_write_set(img_request); 2065 img_request->snapc = rbd_dev->header.snapc; 2066 } else { 2067 img_request->snap_id = rbd_dev->spec->snap_id; 2068 } 2069 if (rbd_dev_parent_get(rbd_dev)) 2070 img_request_layered_set(img_request); 2071 spin_lock_init(&img_request->completion_lock); 2072 img_request->next_completion = 0; 2073 img_request->callback = NULL; 2074 img_request->result = 0; 2075 img_request->obj_request_count = 0; 2076 INIT_LIST_HEAD(&img_request->obj_requests); 2077 kref_init(&img_request->kref); 2078 2079 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev, 2080 write_request ? "write" : "read", offset, length, 2081 img_request); 2082 2083 return img_request; 2084 } 2085 2086 static void rbd_img_request_destroy(struct kref *kref) 2087 { 2088 struct rbd_img_request *img_request; 2089 struct rbd_obj_request *obj_request; 2090 struct rbd_obj_request *next_obj_request; 2091 2092 img_request = container_of(kref, struct rbd_img_request, kref); 2093 2094 dout("%s: img %p\n", __func__, img_request); 2095 2096 for_each_obj_request_safe(img_request, obj_request, next_obj_request) 2097 rbd_img_obj_request_del(img_request, obj_request); 2098 rbd_assert(img_request->obj_request_count == 0); 2099 2100 if (img_request_layered_test(img_request)) { 2101 img_request_layered_clear(img_request); 2102 rbd_dev_parent_put(img_request->rbd_dev); 2103 } 2104 2105 if (img_request_write_test(img_request)) 2106 ceph_put_snap_context(img_request->snapc); 2107 2108 kmem_cache_free(rbd_img_request_cache, img_request); 2109 } 2110 2111 static struct rbd_img_request *rbd_parent_request_create( 2112 struct rbd_obj_request *obj_request, 2113 u64 img_offset, u64 length) 2114 { 2115 struct rbd_img_request *parent_request; 2116 struct rbd_device *rbd_dev; 2117 2118 rbd_assert(obj_request->img_request); 2119 rbd_dev = obj_request->img_request->rbd_dev; 2120 2121 parent_request = rbd_img_request_create(rbd_dev->parent, 2122 img_offset, length, false); 2123 if (!parent_request) 2124 return NULL; 2125 2126 img_request_child_set(parent_request); 2127 rbd_obj_request_get(obj_request); 2128 parent_request->obj_request = obj_request; 2129 2130 return parent_request; 2131 } 2132 2133 static void rbd_parent_request_destroy(struct kref *kref) 2134 { 2135 struct rbd_img_request *parent_request; 2136 struct rbd_obj_request *orig_request; 2137 2138 parent_request = container_of(kref, struct rbd_img_request, kref); 2139 orig_request = parent_request->obj_request; 2140 2141 parent_request->obj_request = NULL; 2142 rbd_obj_request_put(orig_request); 2143 img_request_child_clear(parent_request); 2144 2145 rbd_img_request_destroy(kref); 2146 } 2147 2148 static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request) 2149 { 2150 struct rbd_img_request *img_request; 2151 unsigned int xferred; 2152 int result; 2153 bool more; 2154 2155 rbd_assert(obj_request_img_data_test(obj_request)); 2156 img_request = obj_request->img_request; 2157 2158 rbd_assert(obj_request->xferred <= (u64)UINT_MAX); 2159 xferred = (unsigned int)obj_request->xferred; 2160 result = obj_request->result; 2161 if (result) { 2162 struct rbd_device *rbd_dev = img_request->rbd_dev; 2163 2164 rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n", 2165 img_request_write_test(img_request) ? "write" : "read", 2166 obj_request->length, obj_request->img_offset, 2167 obj_request->offset); 2168 rbd_warn(rbd_dev, " result %d xferred %x\n", 2169 result, xferred); 2170 if (!img_request->result) 2171 img_request->result = result; 2172 } 2173 2174 /* Image object requests don't own their page array */ 2175 2176 if (obj_request->type == OBJ_REQUEST_PAGES) { 2177 obj_request->pages = NULL; 2178 obj_request->page_count = 0; 2179 } 2180 2181 if (img_request_child_test(img_request)) { 2182 rbd_assert(img_request->obj_request != NULL); 2183 more = obj_request->which < img_request->obj_request_count - 1; 2184 } else { 2185 rbd_assert(img_request->rq != NULL); 2186 more = blk_end_request(img_request->rq, result, xferred); 2187 } 2188 2189 return more; 2190 } 2191 2192 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request) 2193 { 2194 struct rbd_img_request *img_request; 2195 u32 which = obj_request->which; 2196 bool more = true; 2197 2198 rbd_assert(obj_request_img_data_test(obj_request)); 2199 img_request = obj_request->img_request; 2200 2201 dout("%s: img %p obj %p\n", __func__, img_request, obj_request); 2202 rbd_assert(img_request != NULL); 2203 rbd_assert(img_request->obj_request_count > 0); 2204 rbd_assert(which != BAD_WHICH); 2205 rbd_assert(which < img_request->obj_request_count); 2206 2207 spin_lock_irq(&img_request->completion_lock); 2208 if (which != img_request->next_completion) 2209 goto out; 2210 2211 for_each_obj_request_from(img_request, obj_request) { 2212 rbd_assert(more); 2213 rbd_assert(which < img_request->obj_request_count); 2214 2215 if (!obj_request_done_test(obj_request)) 2216 break; 2217 more = rbd_img_obj_end_request(obj_request); 2218 which++; 2219 } 2220 2221 rbd_assert(more ^ (which == img_request->obj_request_count)); 2222 img_request->next_completion = which; 2223 out: 2224 spin_unlock_irq(&img_request->completion_lock); 2225 rbd_img_request_put(img_request); 2226 2227 if (!more) 2228 rbd_img_request_complete(img_request); 2229 } 2230 2231 /* 2232 * Split up an image request into one or more object requests, each 2233 * to a different object. The "type" parameter indicates whether 2234 * "data_desc" is the pointer to the head of a list of bio 2235 * structures, or the base of a page array. In either case this 2236 * function assumes data_desc describes memory sufficient to hold 2237 * all data described by the image request. 2238 */ 2239 static int rbd_img_request_fill(struct rbd_img_request *img_request, 2240 enum obj_request_type type, 2241 void *data_desc) 2242 { 2243 struct rbd_device *rbd_dev = img_request->rbd_dev; 2244 struct rbd_obj_request *obj_request = NULL; 2245 struct rbd_obj_request *next_obj_request; 2246 bool write_request = img_request_write_test(img_request); 2247 struct bio *bio_list = NULL; 2248 unsigned int bio_offset = 0; 2249 struct page **pages = NULL; 2250 u64 img_offset; 2251 u64 resid; 2252 u16 opcode; 2253 2254 dout("%s: img %p type %d data_desc %p\n", __func__, img_request, 2255 (int)type, data_desc); 2256 2257 opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ; 2258 img_offset = img_request->offset; 2259 resid = img_request->length; 2260 rbd_assert(resid > 0); 2261 2262 if (type == OBJ_REQUEST_BIO) { 2263 bio_list = data_desc; 2264 rbd_assert(img_offset == 2265 bio_list->bi_iter.bi_sector << SECTOR_SHIFT); 2266 } else { 2267 rbd_assert(type == OBJ_REQUEST_PAGES); 2268 pages = data_desc; 2269 } 2270 2271 while (resid) { 2272 struct ceph_osd_request *osd_req; 2273 const char *object_name; 2274 u64 offset; 2275 u64 length; 2276 unsigned int which = 0; 2277 2278 object_name = rbd_segment_name(rbd_dev, img_offset); 2279 if (!object_name) 2280 goto out_unwind; 2281 offset = rbd_segment_offset(rbd_dev, img_offset); 2282 length = rbd_segment_length(rbd_dev, img_offset, resid); 2283 obj_request = rbd_obj_request_create(object_name, 2284 offset, length, type); 2285 /* object request has its own copy of the object name */ 2286 rbd_segment_name_free(object_name); 2287 if (!obj_request) 2288 goto out_unwind; 2289 2290 /* 2291 * set obj_request->img_request before creating the 2292 * osd_request so that it gets the right snapc 2293 */ 2294 rbd_img_obj_request_add(img_request, obj_request); 2295 2296 if (type == OBJ_REQUEST_BIO) { 2297 unsigned int clone_size; 2298 2299 rbd_assert(length <= (u64)UINT_MAX); 2300 clone_size = (unsigned int)length; 2301 obj_request->bio_list = 2302 bio_chain_clone_range(&bio_list, 2303 &bio_offset, 2304 clone_size, 2305 GFP_ATOMIC); 2306 if (!obj_request->bio_list) 2307 goto out_unwind; 2308 } else { 2309 unsigned int page_count; 2310 2311 obj_request->pages = pages; 2312 page_count = (u32)calc_pages_for(offset, length); 2313 obj_request->page_count = page_count; 2314 if ((offset + length) & ~PAGE_MASK) 2315 page_count--; /* more on last page */ 2316 pages += page_count; 2317 } 2318 2319 osd_req = rbd_osd_req_create(rbd_dev, write_request, 2320 (write_request ? 2 : 1), 2321 obj_request); 2322 if (!osd_req) 2323 goto out_unwind; 2324 obj_request->osd_req = osd_req; 2325 obj_request->callback = rbd_img_obj_callback; 2326 rbd_img_request_get(img_request); 2327 2328 if (write_request) { 2329 osd_req_op_alloc_hint_init(osd_req, which, 2330 rbd_obj_bytes(&rbd_dev->header), 2331 rbd_obj_bytes(&rbd_dev->header)); 2332 which++; 2333 } 2334 2335 osd_req_op_extent_init(osd_req, which, opcode, offset, length, 2336 0, 0); 2337 if (type == OBJ_REQUEST_BIO) 2338 osd_req_op_extent_osd_data_bio(osd_req, which, 2339 obj_request->bio_list, length); 2340 else 2341 osd_req_op_extent_osd_data_pages(osd_req, which, 2342 obj_request->pages, length, 2343 offset & ~PAGE_MASK, false, false); 2344 2345 if (write_request) 2346 rbd_osd_req_format_write(obj_request); 2347 else 2348 rbd_osd_req_format_read(obj_request); 2349 2350 obj_request->img_offset = img_offset; 2351 2352 img_offset += length; 2353 resid -= length; 2354 } 2355 2356 return 0; 2357 2358 out_unwind: 2359 for_each_obj_request_safe(img_request, obj_request, next_obj_request) 2360 rbd_img_obj_request_del(img_request, obj_request); 2361 2362 return -ENOMEM; 2363 } 2364 2365 static void 2366 rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request) 2367 { 2368 struct rbd_img_request *img_request; 2369 struct rbd_device *rbd_dev; 2370 struct page **pages; 2371 u32 page_count; 2372 2373 rbd_assert(obj_request->type == OBJ_REQUEST_BIO); 2374 rbd_assert(obj_request_img_data_test(obj_request)); 2375 img_request = obj_request->img_request; 2376 rbd_assert(img_request); 2377 2378 rbd_dev = img_request->rbd_dev; 2379 rbd_assert(rbd_dev); 2380 2381 pages = obj_request->copyup_pages; 2382 rbd_assert(pages != NULL); 2383 obj_request->copyup_pages = NULL; 2384 page_count = obj_request->copyup_page_count; 2385 rbd_assert(page_count); 2386 obj_request->copyup_page_count = 0; 2387 ceph_release_page_vector(pages, page_count); 2388 2389 /* 2390 * We want the transfer count to reflect the size of the 2391 * original write request. There is no such thing as a 2392 * successful short write, so if the request was successful 2393 * we can just set it to the originally-requested length. 2394 */ 2395 if (!obj_request->result) 2396 obj_request->xferred = obj_request->length; 2397 2398 /* Finish up with the normal image object callback */ 2399 2400 rbd_img_obj_callback(obj_request); 2401 } 2402 2403 static void 2404 rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request) 2405 { 2406 struct rbd_obj_request *orig_request; 2407 struct ceph_osd_request *osd_req; 2408 struct ceph_osd_client *osdc; 2409 struct rbd_device *rbd_dev; 2410 struct page **pages; 2411 u32 page_count; 2412 int img_result; 2413 u64 parent_length; 2414 u64 offset; 2415 u64 length; 2416 2417 rbd_assert(img_request_child_test(img_request)); 2418 2419 /* First get what we need from the image request */ 2420 2421 pages = img_request->copyup_pages; 2422 rbd_assert(pages != NULL); 2423 img_request->copyup_pages = NULL; 2424 page_count = img_request->copyup_page_count; 2425 rbd_assert(page_count); 2426 img_request->copyup_page_count = 0; 2427 2428 orig_request = img_request->obj_request; 2429 rbd_assert(orig_request != NULL); 2430 rbd_assert(obj_request_type_valid(orig_request->type)); 2431 img_result = img_request->result; 2432 parent_length = img_request->length; 2433 rbd_assert(parent_length == img_request->xferred); 2434 rbd_img_request_put(img_request); 2435 2436 rbd_assert(orig_request->img_request); 2437 rbd_dev = orig_request->img_request->rbd_dev; 2438 rbd_assert(rbd_dev); 2439 2440 /* 2441 * If the overlap has become 0 (most likely because the 2442 * image has been flattened) we need to free the pages 2443 * and re-submit the original write request. 2444 */ 2445 if (!rbd_dev->parent_overlap) { 2446 struct ceph_osd_client *osdc; 2447 2448 ceph_release_page_vector(pages, page_count); 2449 osdc = &rbd_dev->rbd_client->client->osdc; 2450 img_result = rbd_obj_request_submit(osdc, orig_request); 2451 if (!img_result) 2452 return; 2453 } 2454 2455 if (img_result) 2456 goto out_err; 2457 2458 /* 2459 * The original osd request is of no use to use any more. 2460 * We need a new one that can hold the three ops in a copyup 2461 * request. Allocate the new copyup osd request for the 2462 * original request, and release the old one. 2463 */ 2464 img_result = -ENOMEM; 2465 osd_req = rbd_osd_req_create_copyup(orig_request); 2466 if (!osd_req) 2467 goto out_err; 2468 rbd_osd_req_destroy(orig_request->osd_req); 2469 orig_request->osd_req = osd_req; 2470 orig_request->copyup_pages = pages; 2471 orig_request->copyup_page_count = page_count; 2472 2473 /* Initialize the copyup op */ 2474 2475 osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup"); 2476 osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0, 2477 false, false); 2478 2479 /* Then the hint op */ 2480 2481 osd_req_op_alloc_hint_init(osd_req, 1, rbd_obj_bytes(&rbd_dev->header), 2482 rbd_obj_bytes(&rbd_dev->header)); 2483 2484 /* And the original write request op */ 2485 2486 offset = orig_request->offset; 2487 length = orig_request->length; 2488 osd_req_op_extent_init(osd_req, 2, CEPH_OSD_OP_WRITE, 2489 offset, length, 0, 0); 2490 if (orig_request->type == OBJ_REQUEST_BIO) 2491 osd_req_op_extent_osd_data_bio(osd_req, 2, 2492 orig_request->bio_list, length); 2493 else 2494 osd_req_op_extent_osd_data_pages(osd_req, 2, 2495 orig_request->pages, length, 2496 offset & ~PAGE_MASK, false, false); 2497 2498 rbd_osd_req_format_write(orig_request); 2499 2500 /* All set, send it off. */ 2501 2502 orig_request->callback = rbd_img_obj_copyup_callback; 2503 osdc = &rbd_dev->rbd_client->client->osdc; 2504 img_result = rbd_obj_request_submit(osdc, orig_request); 2505 if (!img_result) 2506 return; 2507 out_err: 2508 /* Record the error code and complete the request */ 2509 2510 orig_request->result = img_result; 2511 orig_request->xferred = 0; 2512 obj_request_done_set(orig_request); 2513 rbd_obj_request_complete(orig_request); 2514 } 2515 2516 /* 2517 * Read from the parent image the range of data that covers the 2518 * entire target of the given object request. This is used for 2519 * satisfying a layered image write request when the target of an 2520 * object request from the image request does not exist. 2521 * 2522 * A page array big enough to hold the returned data is allocated 2523 * and supplied to rbd_img_request_fill() as the "data descriptor." 2524 * When the read completes, this page array will be transferred to 2525 * the original object request for the copyup operation. 2526 * 2527 * If an error occurs, record it as the result of the original 2528 * object request and mark it done so it gets completed. 2529 */ 2530 static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request) 2531 { 2532 struct rbd_img_request *img_request = NULL; 2533 struct rbd_img_request *parent_request = NULL; 2534 struct rbd_device *rbd_dev; 2535 u64 img_offset; 2536 u64 length; 2537 struct page **pages = NULL; 2538 u32 page_count; 2539 int result; 2540 2541 rbd_assert(obj_request_img_data_test(obj_request)); 2542 rbd_assert(obj_request_type_valid(obj_request->type)); 2543 2544 img_request = obj_request->img_request; 2545 rbd_assert(img_request != NULL); 2546 rbd_dev = img_request->rbd_dev; 2547 rbd_assert(rbd_dev->parent != NULL); 2548 2549 /* 2550 * Determine the byte range covered by the object in the 2551 * child image to which the original request was to be sent. 2552 */ 2553 img_offset = obj_request->img_offset - obj_request->offset; 2554 length = (u64)1 << rbd_dev->header.obj_order; 2555 2556 /* 2557 * There is no defined parent data beyond the parent 2558 * overlap, so limit what we read at that boundary if 2559 * necessary. 2560 */ 2561 if (img_offset + length > rbd_dev->parent_overlap) { 2562 rbd_assert(img_offset < rbd_dev->parent_overlap); 2563 length = rbd_dev->parent_overlap - img_offset; 2564 } 2565 2566 /* 2567 * Allocate a page array big enough to receive the data read 2568 * from the parent. 2569 */ 2570 page_count = (u32)calc_pages_for(0, length); 2571 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); 2572 if (IS_ERR(pages)) { 2573 result = PTR_ERR(pages); 2574 pages = NULL; 2575 goto out_err; 2576 } 2577 2578 result = -ENOMEM; 2579 parent_request = rbd_parent_request_create(obj_request, 2580 img_offset, length); 2581 if (!parent_request) 2582 goto out_err; 2583 2584 result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages); 2585 if (result) 2586 goto out_err; 2587 parent_request->copyup_pages = pages; 2588 parent_request->copyup_page_count = page_count; 2589 2590 parent_request->callback = rbd_img_obj_parent_read_full_callback; 2591 result = rbd_img_request_submit(parent_request); 2592 if (!result) 2593 return 0; 2594 2595 parent_request->copyup_pages = NULL; 2596 parent_request->copyup_page_count = 0; 2597 parent_request->obj_request = NULL; 2598 rbd_obj_request_put(obj_request); 2599 out_err: 2600 if (pages) 2601 ceph_release_page_vector(pages, page_count); 2602 if (parent_request) 2603 rbd_img_request_put(parent_request); 2604 obj_request->result = result; 2605 obj_request->xferred = 0; 2606 obj_request_done_set(obj_request); 2607 2608 return result; 2609 } 2610 2611 static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request) 2612 { 2613 struct rbd_obj_request *orig_request; 2614 struct rbd_device *rbd_dev; 2615 int result; 2616 2617 rbd_assert(!obj_request_img_data_test(obj_request)); 2618 2619 /* 2620 * All we need from the object request is the original 2621 * request and the result of the STAT op. Grab those, then 2622 * we're done with the request. 2623 */ 2624 orig_request = obj_request->obj_request; 2625 obj_request->obj_request = NULL; 2626 rbd_obj_request_put(orig_request); 2627 rbd_assert(orig_request); 2628 rbd_assert(orig_request->img_request); 2629 2630 result = obj_request->result; 2631 obj_request->result = 0; 2632 2633 dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__, 2634 obj_request, orig_request, result, 2635 obj_request->xferred, obj_request->length); 2636 rbd_obj_request_put(obj_request); 2637 2638 /* 2639 * If the overlap has become 0 (most likely because the 2640 * image has been flattened) we need to free the pages 2641 * and re-submit the original write request. 2642 */ 2643 rbd_dev = orig_request->img_request->rbd_dev; 2644 if (!rbd_dev->parent_overlap) { 2645 struct ceph_osd_client *osdc; 2646 2647 osdc = &rbd_dev->rbd_client->client->osdc; 2648 result = rbd_obj_request_submit(osdc, orig_request); 2649 if (!result) 2650 return; 2651 } 2652 2653 /* 2654 * Our only purpose here is to determine whether the object 2655 * exists, and we don't want to treat the non-existence as 2656 * an error. If something else comes back, transfer the 2657 * error to the original request and complete it now. 2658 */ 2659 if (!result) { 2660 obj_request_existence_set(orig_request, true); 2661 } else if (result == -ENOENT) { 2662 obj_request_existence_set(orig_request, false); 2663 } else if (result) { 2664 orig_request->result = result; 2665 goto out; 2666 } 2667 2668 /* 2669 * Resubmit the original request now that we have recorded 2670 * whether the target object exists. 2671 */ 2672 orig_request->result = rbd_img_obj_request_submit(orig_request); 2673 out: 2674 if (orig_request->result) 2675 rbd_obj_request_complete(orig_request); 2676 } 2677 2678 static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request) 2679 { 2680 struct rbd_obj_request *stat_request; 2681 struct rbd_device *rbd_dev; 2682 struct ceph_osd_client *osdc; 2683 struct page **pages = NULL; 2684 u32 page_count; 2685 size_t size; 2686 int ret; 2687 2688 /* 2689 * The response data for a STAT call consists of: 2690 * le64 length; 2691 * struct { 2692 * le32 tv_sec; 2693 * le32 tv_nsec; 2694 * } mtime; 2695 */ 2696 size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32); 2697 page_count = (u32)calc_pages_for(0, size); 2698 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); 2699 if (IS_ERR(pages)) 2700 return PTR_ERR(pages); 2701 2702 ret = -ENOMEM; 2703 stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0, 2704 OBJ_REQUEST_PAGES); 2705 if (!stat_request) 2706 goto out; 2707 2708 rbd_obj_request_get(obj_request); 2709 stat_request->obj_request = obj_request; 2710 stat_request->pages = pages; 2711 stat_request->page_count = page_count; 2712 2713 rbd_assert(obj_request->img_request); 2714 rbd_dev = obj_request->img_request->rbd_dev; 2715 stat_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1, 2716 stat_request); 2717 if (!stat_request->osd_req) 2718 goto out; 2719 stat_request->callback = rbd_img_obj_exists_callback; 2720 2721 osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT); 2722 osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0, 2723 false, false); 2724 rbd_osd_req_format_read(stat_request); 2725 2726 osdc = &rbd_dev->rbd_client->client->osdc; 2727 ret = rbd_obj_request_submit(osdc, stat_request); 2728 out: 2729 if (ret) 2730 rbd_obj_request_put(obj_request); 2731 2732 return ret; 2733 } 2734 2735 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request) 2736 { 2737 struct rbd_img_request *img_request; 2738 struct rbd_device *rbd_dev; 2739 bool known; 2740 2741 rbd_assert(obj_request_img_data_test(obj_request)); 2742 2743 img_request = obj_request->img_request; 2744 rbd_assert(img_request); 2745 rbd_dev = img_request->rbd_dev; 2746 2747 /* 2748 * Only writes to layered images need special handling. 2749 * Reads and non-layered writes are simple object requests. 2750 * Layered writes that start beyond the end of the overlap 2751 * with the parent have no parent data, so they too are 2752 * simple object requests. Finally, if the target object is 2753 * known to already exist, its parent data has already been 2754 * copied, so a write to the object can also be handled as a 2755 * simple object request. 2756 */ 2757 if (!img_request_write_test(img_request) || 2758 !img_request_layered_test(img_request) || 2759 !obj_request_overlaps_parent(obj_request) || 2760 ((known = obj_request_known_test(obj_request)) && 2761 obj_request_exists_test(obj_request))) { 2762 2763 struct rbd_device *rbd_dev; 2764 struct ceph_osd_client *osdc; 2765 2766 rbd_dev = obj_request->img_request->rbd_dev; 2767 osdc = &rbd_dev->rbd_client->client->osdc; 2768 2769 return rbd_obj_request_submit(osdc, obj_request); 2770 } 2771 2772 /* 2773 * It's a layered write. The target object might exist but 2774 * we may not know that yet. If we know it doesn't exist, 2775 * start by reading the data for the full target object from 2776 * the parent so we can use it for a copyup to the target. 2777 */ 2778 if (known) 2779 return rbd_img_obj_parent_read_full(obj_request); 2780 2781 /* We don't know whether the target exists. Go find out. */ 2782 2783 return rbd_img_obj_exists_submit(obj_request); 2784 } 2785 2786 static int rbd_img_request_submit(struct rbd_img_request *img_request) 2787 { 2788 struct rbd_obj_request *obj_request; 2789 struct rbd_obj_request *next_obj_request; 2790 2791 dout("%s: img %p\n", __func__, img_request); 2792 for_each_obj_request_safe(img_request, obj_request, next_obj_request) { 2793 int ret; 2794 2795 ret = rbd_img_obj_request_submit(obj_request); 2796 if (ret) 2797 return ret; 2798 } 2799 2800 return 0; 2801 } 2802 2803 static void rbd_img_parent_read_callback(struct rbd_img_request *img_request) 2804 { 2805 struct rbd_obj_request *obj_request; 2806 struct rbd_device *rbd_dev; 2807 u64 obj_end; 2808 u64 img_xferred; 2809 int img_result; 2810 2811 rbd_assert(img_request_child_test(img_request)); 2812 2813 /* First get what we need from the image request and release it */ 2814 2815 obj_request = img_request->obj_request; 2816 img_xferred = img_request->xferred; 2817 img_result = img_request->result; 2818 rbd_img_request_put(img_request); 2819 2820 /* 2821 * If the overlap has become 0 (most likely because the 2822 * image has been flattened) we need to re-submit the 2823 * original request. 2824 */ 2825 rbd_assert(obj_request); 2826 rbd_assert(obj_request->img_request); 2827 rbd_dev = obj_request->img_request->rbd_dev; 2828 if (!rbd_dev->parent_overlap) { 2829 struct ceph_osd_client *osdc; 2830 2831 osdc = &rbd_dev->rbd_client->client->osdc; 2832 img_result = rbd_obj_request_submit(osdc, obj_request); 2833 if (!img_result) 2834 return; 2835 } 2836 2837 obj_request->result = img_result; 2838 if (obj_request->result) 2839 goto out; 2840 2841 /* 2842 * We need to zero anything beyond the parent overlap 2843 * boundary. Since rbd_img_obj_request_read_callback() 2844 * will zero anything beyond the end of a short read, an 2845 * easy way to do this is to pretend the data from the 2846 * parent came up short--ending at the overlap boundary. 2847 */ 2848 rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length); 2849 obj_end = obj_request->img_offset + obj_request->length; 2850 if (obj_end > rbd_dev->parent_overlap) { 2851 u64 xferred = 0; 2852 2853 if (obj_request->img_offset < rbd_dev->parent_overlap) 2854 xferred = rbd_dev->parent_overlap - 2855 obj_request->img_offset; 2856 2857 obj_request->xferred = min(img_xferred, xferred); 2858 } else { 2859 obj_request->xferred = img_xferred; 2860 } 2861 out: 2862 rbd_img_obj_request_read_callback(obj_request); 2863 rbd_obj_request_complete(obj_request); 2864 } 2865 2866 static void rbd_img_parent_read(struct rbd_obj_request *obj_request) 2867 { 2868 struct rbd_img_request *img_request; 2869 int result; 2870 2871 rbd_assert(obj_request_img_data_test(obj_request)); 2872 rbd_assert(obj_request->img_request != NULL); 2873 rbd_assert(obj_request->result == (s32) -ENOENT); 2874 rbd_assert(obj_request_type_valid(obj_request->type)); 2875 2876 /* rbd_read_finish(obj_request, obj_request->length); */ 2877 img_request = rbd_parent_request_create(obj_request, 2878 obj_request->img_offset, 2879 obj_request->length); 2880 result = -ENOMEM; 2881 if (!img_request) 2882 goto out_err; 2883 2884 if (obj_request->type == OBJ_REQUEST_BIO) 2885 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO, 2886 obj_request->bio_list); 2887 else 2888 result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES, 2889 obj_request->pages); 2890 if (result) 2891 goto out_err; 2892 2893 img_request->callback = rbd_img_parent_read_callback; 2894 result = rbd_img_request_submit(img_request); 2895 if (result) 2896 goto out_err; 2897 2898 return; 2899 out_err: 2900 if (img_request) 2901 rbd_img_request_put(img_request); 2902 obj_request->result = result; 2903 obj_request->xferred = 0; 2904 obj_request_done_set(obj_request); 2905 } 2906 2907 static int rbd_obj_notify_ack_sync(struct rbd_device *rbd_dev, u64 notify_id) 2908 { 2909 struct rbd_obj_request *obj_request; 2910 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 2911 int ret; 2912 2913 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0, 2914 OBJ_REQUEST_NODATA); 2915 if (!obj_request) 2916 return -ENOMEM; 2917 2918 ret = -ENOMEM; 2919 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1, 2920 obj_request); 2921 if (!obj_request->osd_req) 2922 goto out; 2923 2924 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK, 2925 notify_id, 0, 0); 2926 rbd_osd_req_format_read(obj_request); 2927 2928 ret = rbd_obj_request_submit(osdc, obj_request); 2929 if (ret) 2930 goto out; 2931 ret = rbd_obj_request_wait(obj_request); 2932 out: 2933 rbd_obj_request_put(obj_request); 2934 2935 return ret; 2936 } 2937 2938 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data) 2939 { 2940 struct rbd_device *rbd_dev = (struct rbd_device *)data; 2941 int ret; 2942 2943 if (!rbd_dev) 2944 return; 2945 2946 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__, 2947 rbd_dev->header_name, (unsigned long long)notify_id, 2948 (unsigned int)opcode); 2949 ret = rbd_dev_refresh(rbd_dev); 2950 if (ret) 2951 rbd_warn(rbd_dev, "header refresh error (%d)\n", ret); 2952 2953 rbd_obj_notify_ack_sync(rbd_dev, notify_id); 2954 } 2955 2956 /* 2957 * Initiate a watch request, synchronously. 2958 */ 2959 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev) 2960 { 2961 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 2962 struct rbd_obj_request *obj_request; 2963 int ret; 2964 2965 rbd_assert(!rbd_dev->watch_event); 2966 rbd_assert(!rbd_dev->watch_request); 2967 2968 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev, 2969 &rbd_dev->watch_event); 2970 if (ret < 0) 2971 return ret; 2972 2973 rbd_assert(rbd_dev->watch_event); 2974 2975 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0, 2976 OBJ_REQUEST_NODATA); 2977 if (!obj_request) { 2978 ret = -ENOMEM; 2979 goto out_cancel; 2980 } 2981 2982 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1, 2983 obj_request); 2984 if (!obj_request->osd_req) { 2985 ret = -ENOMEM; 2986 goto out_put; 2987 } 2988 2989 ceph_osdc_set_request_linger(osdc, obj_request->osd_req); 2990 2991 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH, 2992 rbd_dev->watch_event->cookie, 0, 1); 2993 rbd_osd_req_format_write(obj_request); 2994 2995 ret = rbd_obj_request_submit(osdc, obj_request); 2996 if (ret) 2997 goto out_linger; 2998 2999 ret = rbd_obj_request_wait(obj_request); 3000 if (ret) 3001 goto out_linger; 3002 3003 ret = obj_request->result; 3004 if (ret) 3005 goto out_linger; 3006 3007 /* 3008 * A watch request is set to linger, so the underlying osd 3009 * request won't go away until we unregister it. We retain 3010 * a pointer to the object request during that time (in 3011 * rbd_dev->watch_request), so we'll keep a reference to 3012 * it. We'll drop that reference (below) after we've 3013 * unregistered it. 3014 */ 3015 rbd_dev->watch_request = obj_request; 3016 3017 return 0; 3018 3019 out_linger: 3020 ceph_osdc_unregister_linger_request(osdc, obj_request->osd_req); 3021 out_put: 3022 rbd_obj_request_put(obj_request); 3023 out_cancel: 3024 ceph_osdc_cancel_event(rbd_dev->watch_event); 3025 rbd_dev->watch_event = NULL; 3026 3027 return ret; 3028 } 3029 3030 /* 3031 * Tear down a watch request, synchronously. 3032 */ 3033 static int __rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev) 3034 { 3035 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3036 struct rbd_obj_request *obj_request; 3037 int ret; 3038 3039 rbd_assert(rbd_dev->watch_event); 3040 rbd_assert(rbd_dev->watch_request); 3041 3042 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0, 3043 OBJ_REQUEST_NODATA); 3044 if (!obj_request) { 3045 ret = -ENOMEM; 3046 goto out_cancel; 3047 } 3048 3049 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1, 3050 obj_request); 3051 if (!obj_request->osd_req) { 3052 ret = -ENOMEM; 3053 goto out_put; 3054 } 3055 3056 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH, 3057 rbd_dev->watch_event->cookie, 0, 0); 3058 rbd_osd_req_format_write(obj_request); 3059 3060 ret = rbd_obj_request_submit(osdc, obj_request); 3061 if (ret) 3062 goto out_put; 3063 3064 ret = rbd_obj_request_wait(obj_request); 3065 if (ret) 3066 goto out_put; 3067 3068 ret = obj_request->result; 3069 if (ret) 3070 goto out_put; 3071 3072 /* We have successfully torn down the watch request */ 3073 3074 ceph_osdc_unregister_linger_request(osdc, 3075 rbd_dev->watch_request->osd_req); 3076 rbd_obj_request_put(rbd_dev->watch_request); 3077 rbd_dev->watch_request = NULL; 3078 3079 out_put: 3080 rbd_obj_request_put(obj_request); 3081 out_cancel: 3082 ceph_osdc_cancel_event(rbd_dev->watch_event); 3083 rbd_dev->watch_event = NULL; 3084 3085 return ret; 3086 } 3087 3088 static void rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev) 3089 { 3090 int ret; 3091 3092 ret = __rbd_dev_header_unwatch_sync(rbd_dev); 3093 if (ret) { 3094 rbd_warn(rbd_dev, "unable to tear down watch request: %d\n", 3095 ret); 3096 } 3097 } 3098 3099 /* 3100 * Synchronous osd object method call. Returns the number of bytes 3101 * returned in the outbound buffer, or a negative error code. 3102 */ 3103 static int rbd_obj_method_sync(struct rbd_device *rbd_dev, 3104 const char *object_name, 3105 const char *class_name, 3106 const char *method_name, 3107 const void *outbound, 3108 size_t outbound_size, 3109 void *inbound, 3110 size_t inbound_size) 3111 { 3112 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3113 struct rbd_obj_request *obj_request; 3114 struct page **pages; 3115 u32 page_count; 3116 int ret; 3117 3118 /* 3119 * Method calls are ultimately read operations. The result 3120 * should placed into the inbound buffer provided. They 3121 * also supply outbound data--parameters for the object 3122 * method. Currently if this is present it will be a 3123 * snapshot id. 3124 */ 3125 page_count = (u32)calc_pages_for(0, inbound_size); 3126 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); 3127 if (IS_ERR(pages)) 3128 return PTR_ERR(pages); 3129 3130 ret = -ENOMEM; 3131 obj_request = rbd_obj_request_create(object_name, 0, inbound_size, 3132 OBJ_REQUEST_PAGES); 3133 if (!obj_request) 3134 goto out; 3135 3136 obj_request->pages = pages; 3137 obj_request->page_count = page_count; 3138 3139 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1, 3140 obj_request); 3141 if (!obj_request->osd_req) 3142 goto out; 3143 3144 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL, 3145 class_name, method_name); 3146 if (outbound_size) { 3147 struct ceph_pagelist *pagelist; 3148 3149 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS); 3150 if (!pagelist) 3151 goto out; 3152 3153 ceph_pagelist_init(pagelist); 3154 ceph_pagelist_append(pagelist, outbound, outbound_size); 3155 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0, 3156 pagelist); 3157 } 3158 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0, 3159 obj_request->pages, inbound_size, 3160 0, false, false); 3161 rbd_osd_req_format_read(obj_request); 3162 3163 ret = rbd_obj_request_submit(osdc, obj_request); 3164 if (ret) 3165 goto out; 3166 ret = rbd_obj_request_wait(obj_request); 3167 if (ret) 3168 goto out; 3169 3170 ret = obj_request->result; 3171 if (ret < 0) 3172 goto out; 3173 3174 rbd_assert(obj_request->xferred < (u64)INT_MAX); 3175 ret = (int)obj_request->xferred; 3176 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred); 3177 out: 3178 if (obj_request) 3179 rbd_obj_request_put(obj_request); 3180 else 3181 ceph_release_page_vector(pages, page_count); 3182 3183 return ret; 3184 } 3185 3186 static void rbd_request_fn(struct request_queue *q) 3187 __releases(q->queue_lock) __acquires(q->queue_lock) 3188 { 3189 struct rbd_device *rbd_dev = q->queuedata; 3190 struct request *rq; 3191 int result; 3192 3193 while ((rq = blk_fetch_request(q))) { 3194 bool write_request = rq_data_dir(rq) == WRITE; 3195 struct rbd_img_request *img_request; 3196 u64 offset; 3197 u64 length; 3198 3199 /* Ignore any non-FS requests that filter through. */ 3200 3201 if (rq->cmd_type != REQ_TYPE_FS) { 3202 dout("%s: non-fs request type %d\n", __func__, 3203 (int) rq->cmd_type); 3204 __blk_end_request_all(rq, 0); 3205 continue; 3206 } 3207 3208 /* Ignore/skip any zero-length requests */ 3209 3210 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT; 3211 length = (u64) blk_rq_bytes(rq); 3212 3213 if (!length) { 3214 dout("%s: zero-length request\n", __func__); 3215 __blk_end_request_all(rq, 0); 3216 continue; 3217 } 3218 3219 spin_unlock_irq(q->queue_lock); 3220 3221 /* Disallow writes to a read-only device */ 3222 3223 if (write_request) { 3224 result = -EROFS; 3225 if (rbd_dev->mapping.read_only) 3226 goto end_request; 3227 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP); 3228 } 3229 3230 /* 3231 * Quit early if the mapped snapshot no longer 3232 * exists. It's still possible the snapshot will 3233 * have disappeared by the time our request arrives 3234 * at the osd, but there's no sense in sending it if 3235 * we already know. 3236 */ 3237 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) { 3238 dout("request for non-existent snapshot"); 3239 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP); 3240 result = -ENXIO; 3241 goto end_request; 3242 } 3243 3244 result = -EINVAL; 3245 if (offset && length > U64_MAX - offset + 1) { 3246 rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n", 3247 offset, length); 3248 goto end_request; /* Shouldn't happen */ 3249 } 3250 3251 result = -EIO; 3252 if (offset + length > rbd_dev->mapping.size) { 3253 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)\n", 3254 offset, length, rbd_dev->mapping.size); 3255 goto end_request; 3256 } 3257 3258 result = -ENOMEM; 3259 img_request = rbd_img_request_create(rbd_dev, offset, length, 3260 write_request); 3261 if (!img_request) 3262 goto end_request; 3263 3264 img_request->rq = rq; 3265 3266 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO, 3267 rq->bio); 3268 if (!result) 3269 result = rbd_img_request_submit(img_request); 3270 if (result) 3271 rbd_img_request_put(img_request); 3272 end_request: 3273 spin_lock_irq(q->queue_lock); 3274 if (result < 0) { 3275 rbd_warn(rbd_dev, "%s %llx at %llx result %d\n", 3276 write_request ? "write" : "read", 3277 length, offset, result); 3278 3279 __blk_end_request_all(rq, result); 3280 } 3281 } 3282 } 3283 3284 /* 3285 * a queue callback. Makes sure that we don't create a bio that spans across 3286 * multiple osd objects. One exception would be with a single page bios, 3287 * which we handle later at bio_chain_clone_range() 3288 */ 3289 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd, 3290 struct bio_vec *bvec) 3291 { 3292 struct rbd_device *rbd_dev = q->queuedata; 3293 sector_t sector_offset; 3294 sector_t sectors_per_obj; 3295 sector_t obj_sector_offset; 3296 int ret; 3297 3298 /* 3299 * Find how far into its rbd object the partition-relative 3300 * bio start sector is to offset relative to the enclosing 3301 * device. 3302 */ 3303 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector; 3304 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT); 3305 obj_sector_offset = sector_offset & (sectors_per_obj - 1); 3306 3307 /* 3308 * Compute the number of bytes from that offset to the end 3309 * of the object. Account for what's already used by the bio. 3310 */ 3311 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT; 3312 if (ret > bmd->bi_size) 3313 ret -= bmd->bi_size; 3314 else 3315 ret = 0; 3316 3317 /* 3318 * Don't send back more than was asked for. And if the bio 3319 * was empty, let the whole thing through because: "Note 3320 * that a block device *must* allow a single page to be 3321 * added to an empty bio." 3322 */ 3323 rbd_assert(bvec->bv_len <= PAGE_SIZE); 3324 if (ret > (int) bvec->bv_len || !bmd->bi_size) 3325 ret = (int) bvec->bv_len; 3326 3327 return ret; 3328 } 3329 3330 static void rbd_free_disk(struct rbd_device *rbd_dev) 3331 { 3332 struct gendisk *disk = rbd_dev->disk; 3333 3334 if (!disk) 3335 return; 3336 3337 rbd_dev->disk = NULL; 3338 if (disk->flags & GENHD_FL_UP) { 3339 del_gendisk(disk); 3340 if (disk->queue) 3341 blk_cleanup_queue(disk->queue); 3342 } 3343 put_disk(disk); 3344 } 3345 3346 static int rbd_obj_read_sync(struct rbd_device *rbd_dev, 3347 const char *object_name, 3348 u64 offset, u64 length, void *buf) 3349 3350 { 3351 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 3352 struct rbd_obj_request *obj_request; 3353 struct page **pages = NULL; 3354 u32 page_count; 3355 size_t size; 3356 int ret; 3357 3358 page_count = (u32) calc_pages_for(offset, length); 3359 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); 3360 if (IS_ERR(pages)) 3361 ret = PTR_ERR(pages); 3362 3363 ret = -ENOMEM; 3364 obj_request = rbd_obj_request_create(object_name, offset, length, 3365 OBJ_REQUEST_PAGES); 3366 if (!obj_request) 3367 goto out; 3368 3369 obj_request->pages = pages; 3370 obj_request->page_count = page_count; 3371 3372 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1, 3373 obj_request); 3374 if (!obj_request->osd_req) 3375 goto out; 3376 3377 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ, 3378 offset, length, 0, 0); 3379 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0, 3380 obj_request->pages, 3381 obj_request->length, 3382 obj_request->offset & ~PAGE_MASK, 3383 false, false); 3384 rbd_osd_req_format_read(obj_request); 3385 3386 ret = rbd_obj_request_submit(osdc, obj_request); 3387 if (ret) 3388 goto out; 3389 ret = rbd_obj_request_wait(obj_request); 3390 if (ret) 3391 goto out; 3392 3393 ret = obj_request->result; 3394 if (ret < 0) 3395 goto out; 3396 3397 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX); 3398 size = (size_t) obj_request->xferred; 3399 ceph_copy_from_page_vector(pages, buf, 0, size); 3400 rbd_assert(size <= (size_t)INT_MAX); 3401 ret = (int)size; 3402 out: 3403 if (obj_request) 3404 rbd_obj_request_put(obj_request); 3405 else 3406 ceph_release_page_vector(pages, page_count); 3407 3408 return ret; 3409 } 3410 3411 /* 3412 * Read the complete header for the given rbd device. On successful 3413 * return, the rbd_dev->header field will contain up-to-date 3414 * information about the image. 3415 */ 3416 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev) 3417 { 3418 struct rbd_image_header_ondisk *ondisk = NULL; 3419 u32 snap_count = 0; 3420 u64 names_size = 0; 3421 u32 want_count; 3422 int ret; 3423 3424 /* 3425 * The complete header will include an array of its 64-bit 3426 * snapshot ids, followed by the names of those snapshots as 3427 * a contiguous block of NUL-terminated strings. Note that 3428 * the number of snapshots could change by the time we read 3429 * it in, in which case we re-read it. 3430 */ 3431 do { 3432 size_t size; 3433 3434 kfree(ondisk); 3435 3436 size = sizeof (*ondisk); 3437 size += snap_count * sizeof (struct rbd_image_snap_ondisk); 3438 size += names_size; 3439 ondisk = kmalloc(size, GFP_KERNEL); 3440 if (!ondisk) 3441 return -ENOMEM; 3442 3443 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name, 3444 0, size, ondisk); 3445 if (ret < 0) 3446 goto out; 3447 if ((size_t)ret < size) { 3448 ret = -ENXIO; 3449 rbd_warn(rbd_dev, "short header read (want %zd got %d)", 3450 size, ret); 3451 goto out; 3452 } 3453 if (!rbd_dev_ondisk_valid(ondisk)) { 3454 ret = -ENXIO; 3455 rbd_warn(rbd_dev, "invalid header"); 3456 goto out; 3457 } 3458 3459 names_size = le64_to_cpu(ondisk->snap_names_len); 3460 want_count = snap_count; 3461 snap_count = le32_to_cpu(ondisk->snap_count); 3462 } while (snap_count != want_count); 3463 3464 ret = rbd_header_from_disk(rbd_dev, ondisk); 3465 out: 3466 kfree(ondisk); 3467 3468 return ret; 3469 } 3470 3471 /* 3472 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to 3473 * has disappeared from the (just updated) snapshot context. 3474 */ 3475 static void rbd_exists_validate(struct rbd_device *rbd_dev) 3476 { 3477 u64 snap_id; 3478 3479 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) 3480 return; 3481 3482 snap_id = rbd_dev->spec->snap_id; 3483 if (snap_id == CEPH_NOSNAP) 3484 return; 3485 3486 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX) 3487 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); 3488 } 3489 3490 static void rbd_dev_update_size(struct rbd_device *rbd_dev) 3491 { 3492 sector_t size; 3493 bool removing; 3494 3495 /* 3496 * Don't hold the lock while doing disk operations, 3497 * or lock ordering will conflict with the bdev mutex via: 3498 * rbd_add() -> blkdev_get() -> rbd_open() 3499 */ 3500 spin_lock_irq(&rbd_dev->lock); 3501 removing = test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags); 3502 spin_unlock_irq(&rbd_dev->lock); 3503 /* 3504 * If the device is being removed, rbd_dev->disk has 3505 * been destroyed, so don't try to update its size 3506 */ 3507 if (!removing) { 3508 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE; 3509 dout("setting size to %llu sectors", (unsigned long long)size); 3510 set_capacity(rbd_dev->disk, size); 3511 revalidate_disk(rbd_dev->disk); 3512 } 3513 } 3514 3515 static int rbd_dev_refresh(struct rbd_device *rbd_dev) 3516 { 3517 u64 mapping_size; 3518 int ret; 3519 3520 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 3521 down_write(&rbd_dev->header_rwsem); 3522 mapping_size = rbd_dev->mapping.size; 3523 if (rbd_dev->image_format == 1) 3524 ret = rbd_dev_v1_header_info(rbd_dev); 3525 else 3526 ret = rbd_dev_v2_header_info(rbd_dev); 3527 3528 /* If it's a mapped snapshot, validate its EXISTS flag */ 3529 3530 rbd_exists_validate(rbd_dev); 3531 up_write(&rbd_dev->header_rwsem); 3532 3533 if (mapping_size != rbd_dev->mapping.size) { 3534 rbd_dev_update_size(rbd_dev); 3535 } 3536 3537 return ret; 3538 } 3539 3540 static int rbd_init_disk(struct rbd_device *rbd_dev) 3541 { 3542 struct gendisk *disk; 3543 struct request_queue *q; 3544 u64 segment_size; 3545 3546 /* create gendisk info */ 3547 disk = alloc_disk(single_major ? 3548 (1 << RBD_SINGLE_MAJOR_PART_SHIFT) : 3549 RBD_MINORS_PER_MAJOR); 3550 if (!disk) 3551 return -ENOMEM; 3552 3553 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d", 3554 rbd_dev->dev_id); 3555 disk->major = rbd_dev->major; 3556 disk->first_minor = rbd_dev->minor; 3557 if (single_major) 3558 disk->flags |= GENHD_FL_EXT_DEVT; 3559 disk->fops = &rbd_bd_ops; 3560 disk->private_data = rbd_dev; 3561 3562 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock); 3563 if (!q) 3564 goto out_disk; 3565 3566 /* We use the default size, but let's be explicit about it. */ 3567 blk_queue_physical_block_size(q, SECTOR_SIZE); 3568 3569 /* set io sizes to object size */ 3570 segment_size = rbd_obj_bytes(&rbd_dev->header); 3571 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE); 3572 blk_queue_max_segment_size(q, segment_size); 3573 blk_queue_io_min(q, segment_size); 3574 blk_queue_io_opt(q, segment_size); 3575 3576 blk_queue_merge_bvec(q, rbd_merge_bvec); 3577 disk->queue = q; 3578 3579 q->queuedata = rbd_dev; 3580 3581 rbd_dev->disk = disk; 3582 3583 return 0; 3584 out_disk: 3585 put_disk(disk); 3586 3587 return -ENOMEM; 3588 } 3589 3590 /* 3591 sysfs 3592 */ 3593 3594 static struct rbd_device *dev_to_rbd_dev(struct device *dev) 3595 { 3596 return container_of(dev, struct rbd_device, dev); 3597 } 3598 3599 static ssize_t rbd_size_show(struct device *dev, 3600 struct device_attribute *attr, char *buf) 3601 { 3602 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3603 3604 return sprintf(buf, "%llu\n", 3605 (unsigned long long)rbd_dev->mapping.size); 3606 } 3607 3608 /* 3609 * Note this shows the features for whatever's mapped, which is not 3610 * necessarily the base image. 3611 */ 3612 static ssize_t rbd_features_show(struct device *dev, 3613 struct device_attribute *attr, char *buf) 3614 { 3615 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3616 3617 return sprintf(buf, "0x%016llx\n", 3618 (unsigned long long)rbd_dev->mapping.features); 3619 } 3620 3621 static ssize_t rbd_major_show(struct device *dev, 3622 struct device_attribute *attr, char *buf) 3623 { 3624 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3625 3626 if (rbd_dev->major) 3627 return sprintf(buf, "%d\n", rbd_dev->major); 3628 3629 return sprintf(buf, "(none)\n"); 3630 } 3631 3632 static ssize_t rbd_minor_show(struct device *dev, 3633 struct device_attribute *attr, char *buf) 3634 { 3635 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3636 3637 return sprintf(buf, "%d\n", rbd_dev->minor); 3638 } 3639 3640 static ssize_t rbd_client_id_show(struct device *dev, 3641 struct device_attribute *attr, char *buf) 3642 { 3643 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3644 3645 return sprintf(buf, "client%lld\n", 3646 ceph_client_id(rbd_dev->rbd_client->client)); 3647 } 3648 3649 static ssize_t rbd_pool_show(struct device *dev, 3650 struct device_attribute *attr, char *buf) 3651 { 3652 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3653 3654 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name); 3655 } 3656 3657 static ssize_t rbd_pool_id_show(struct device *dev, 3658 struct device_attribute *attr, char *buf) 3659 { 3660 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3661 3662 return sprintf(buf, "%llu\n", 3663 (unsigned long long) rbd_dev->spec->pool_id); 3664 } 3665 3666 static ssize_t rbd_name_show(struct device *dev, 3667 struct device_attribute *attr, char *buf) 3668 { 3669 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3670 3671 if (rbd_dev->spec->image_name) 3672 return sprintf(buf, "%s\n", rbd_dev->spec->image_name); 3673 3674 return sprintf(buf, "(unknown)\n"); 3675 } 3676 3677 static ssize_t rbd_image_id_show(struct device *dev, 3678 struct device_attribute *attr, char *buf) 3679 { 3680 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3681 3682 return sprintf(buf, "%s\n", rbd_dev->spec->image_id); 3683 } 3684 3685 /* 3686 * Shows the name of the currently-mapped snapshot (or 3687 * RBD_SNAP_HEAD_NAME for the base image). 3688 */ 3689 static ssize_t rbd_snap_show(struct device *dev, 3690 struct device_attribute *attr, 3691 char *buf) 3692 { 3693 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3694 3695 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name); 3696 } 3697 3698 /* 3699 * For an rbd v2 image, shows the pool id, image id, and snapshot id 3700 * for the parent image. If there is no parent, simply shows 3701 * "(no parent image)". 3702 */ 3703 static ssize_t rbd_parent_show(struct device *dev, 3704 struct device_attribute *attr, 3705 char *buf) 3706 { 3707 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3708 struct rbd_spec *spec = rbd_dev->parent_spec; 3709 int count; 3710 char *bufp = buf; 3711 3712 if (!spec) 3713 return sprintf(buf, "(no parent image)\n"); 3714 3715 count = sprintf(bufp, "pool_id %llu\npool_name %s\n", 3716 (unsigned long long) spec->pool_id, spec->pool_name); 3717 if (count < 0) 3718 return count; 3719 bufp += count; 3720 3721 count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id, 3722 spec->image_name ? spec->image_name : "(unknown)"); 3723 if (count < 0) 3724 return count; 3725 bufp += count; 3726 3727 count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n", 3728 (unsigned long long) spec->snap_id, spec->snap_name); 3729 if (count < 0) 3730 return count; 3731 bufp += count; 3732 3733 count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap); 3734 if (count < 0) 3735 return count; 3736 bufp += count; 3737 3738 return (ssize_t) (bufp - buf); 3739 } 3740 3741 static ssize_t rbd_image_refresh(struct device *dev, 3742 struct device_attribute *attr, 3743 const char *buf, 3744 size_t size) 3745 { 3746 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 3747 int ret; 3748 3749 ret = rbd_dev_refresh(rbd_dev); 3750 if (ret) 3751 rbd_warn(rbd_dev, ": manual header refresh error (%d)\n", ret); 3752 3753 return ret < 0 ? ret : size; 3754 } 3755 3756 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL); 3757 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL); 3758 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL); 3759 static DEVICE_ATTR(minor, S_IRUGO, rbd_minor_show, NULL); 3760 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL); 3761 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL); 3762 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL); 3763 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL); 3764 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL); 3765 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh); 3766 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL); 3767 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL); 3768 3769 static struct attribute *rbd_attrs[] = { 3770 &dev_attr_size.attr, 3771 &dev_attr_features.attr, 3772 &dev_attr_major.attr, 3773 &dev_attr_minor.attr, 3774 &dev_attr_client_id.attr, 3775 &dev_attr_pool.attr, 3776 &dev_attr_pool_id.attr, 3777 &dev_attr_name.attr, 3778 &dev_attr_image_id.attr, 3779 &dev_attr_current_snap.attr, 3780 &dev_attr_parent.attr, 3781 &dev_attr_refresh.attr, 3782 NULL 3783 }; 3784 3785 static struct attribute_group rbd_attr_group = { 3786 .attrs = rbd_attrs, 3787 }; 3788 3789 static const struct attribute_group *rbd_attr_groups[] = { 3790 &rbd_attr_group, 3791 NULL 3792 }; 3793 3794 static void rbd_sysfs_dev_release(struct device *dev) 3795 { 3796 } 3797 3798 static struct device_type rbd_device_type = { 3799 .name = "rbd", 3800 .groups = rbd_attr_groups, 3801 .release = rbd_sysfs_dev_release, 3802 }; 3803 3804 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec) 3805 { 3806 kref_get(&spec->kref); 3807 3808 return spec; 3809 } 3810 3811 static void rbd_spec_free(struct kref *kref); 3812 static void rbd_spec_put(struct rbd_spec *spec) 3813 { 3814 if (spec) 3815 kref_put(&spec->kref, rbd_spec_free); 3816 } 3817 3818 static struct rbd_spec *rbd_spec_alloc(void) 3819 { 3820 struct rbd_spec *spec; 3821 3822 spec = kzalloc(sizeof (*spec), GFP_KERNEL); 3823 if (!spec) 3824 return NULL; 3825 kref_init(&spec->kref); 3826 3827 return spec; 3828 } 3829 3830 static void rbd_spec_free(struct kref *kref) 3831 { 3832 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref); 3833 3834 kfree(spec->pool_name); 3835 kfree(spec->image_id); 3836 kfree(spec->image_name); 3837 kfree(spec->snap_name); 3838 kfree(spec); 3839 } 3840 3841 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, 3842 struct rbd_spec *spec) 3843 { 3844 struct rbd_device *rbd_dev; 3845 3846 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL); 3847 if (!rbd_dev) 3848 return NULL; 3849 3850 spin_lock_init(&rbd_dev->lock); 3851 rbd_dev->flags = 0; 3852 atomic_set(&rbd_dev->parent_ref, 0); 3853 INIT_LIST_HEAD(&rbd_dev->node); 3854 init_rwsem(&rbd_dev->header_rwsem); 3855 3856 rbd_dev->spec = spec; 3857 rbd_dev->rbd_client = rbdc; 3858 3859 /* Initialize the layout used for all rbd requests */ 3860 3861 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER); 3862 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1); 3863 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER); 3864 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id); 3865 3866 return rbd_dev; 3867 } 3868 3869 static void rbd_dev_destroy(struct rbd_device *rbd_dev) 3870 { 3871 rbd_put_client(rbd_dev->rbd_client); 3872 rbd_spec_put(rbd_dev->spec); 3873 kfree(rbd_dev); 3874 } 3875 3876 /* 3877 * Get the size and object order for an image snapshot, or if 3878 * snap_id is CEPH_NOSNAP, gets this information for the base 3879 * image. 3880 */ 3881 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, 3882 u8 *order, u64 *snap_size) 3883 { 3884 __le64 snapid = cpu_to_le64(snap_id); 3885 int ret; 3886 struct { 3887 u8 order; 3888 __le64 size; 3889 } __attribute__ ((packed)) size_buf = { 0 }; 3890 3891 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, 3892 "rbd", "get_size", 3893 &snapid, sizeof (snapid), 3894 &size_buf, sizeof (size_buf)); 3895 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 3896 if (ret < 0) 3897 return ret; 3898 if (ret < sizeof (size_buf)) 3899 return -ERANGE; 3900 3901 if (order) { 3902 *order = size_buf.order; 3903 dout(" order %u", (unsigned int)*order); 3904 } 3905 *snap_size = le64_to_cpu(size_buf.size); 3906 3907 dout(" snap_id 0x%016llx snap_size = %llu\n", 3908 (unsigned long long)snap_id, 3909 (unsigned long long)*snap_size); 3910 3911 return 0; 3912 } 3913 3914 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev) 3915 { 3916 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP, 3917 &rbd_dev->header.obj_order, 3918 &rbd_dev->header.image_size); 3919 } 3920 3921 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev) 3922 { 3923 void *reply_buf; 3924 int ret; 3925 void *p; 3926 3927 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL); 3928 if (!reply_buf) 3929 return -ENOMEM; 3930 3931 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, 3932 "rbd", "get_object_prefix", NULL, 0, 3933 reply_buf, RBD_OBJ_PREFIX_LEN_MAX); 3934 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 3935 if (ret < 0) 3936 goto out; 3937 3938 p = reply_buf; 3939 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p, 3940 p + ret, NULL, GFP_NOIO); 3941 ret = 0; 3942 3943 if (IS_ERR(rbd_dev->header.object_prefix)) { 3944 ret = PTR_ERR(rbd_dev->header.object_prefix); 3945 rbd_dev->header.object_prefix = NULL; 3946 } else { 3947 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix); 3948 } 3949 out: 3950 kfree(reply_buf); 3951 3952 return ret; 3953 } 3954 3955 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, 3956 u64 *snap_features) 3957 { 3958 __le64 snapid = cpu_to_le64(snap_id); 3959 struct { 3960 __le64 features; 3961 __le64 incompat; 3962 } __attribute__ ((packed)) features_buf = { 0 }; 3963 u64 incompat; 3964 int ret; 3965 3966 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, 3967 "rbd", "get_features", 3968 &snapid, sizeof (snapid), 3969 &features_buf, sizeof (features_buf)); 3970 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 3971 if (ret < 0) 3972 return ret; 3973 if (ret < sizeof (features_buf)) 3974 return -ERANGE; 3975 3976 incompat = le64_to_cpu(features_buf.incompat); 3977 if (incompat & ~RBD_FEATURES_SUPPORTED) 3978 return -ENXIO; 3979 3980 *snap_features = le64_to_cpu(features_buf.features); 3981 3982 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n", 3983 (unsigned long long)snap_id, 3984 (unsigned long long)*snap_features, 3985 (unsigned long long)le64_to_cpu(features_buf.incompat)); 3986 3987 return 0; 3988 } 3989 3990 static int rbd_dev_v2_features(struct rbd_device *rbd_dev) 3991 { 3992 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP, 3993 &rbd_dev->header.features); 3994 } 3995 3996 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev) 3997 { 3998 struct rbd_spec *parent_spec; 3999 size_t size; 4000 void *reply_buf = NULL; 4001 __le64 snapid; 4002 void *p; 4003 void *end; 4004 u64 pool_id; 4005 char *image_id; 4006 u64 snap_id; 4007 u64 overlap; 4008 int ret; 4009 4010 parent_spec = rbd_spec_alloc(); 4011 if (!parent_spec) 4012 return -ENOMEM; 4013 4014 size = sizeof (__le64) + /* pool_id */ 4015 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */ 4016 sizeof (__le64) + /* snap_id */ 4017 sizeof (__le64); /* overlap */ 4018 reply_buf = kmalloc(size, GFP_KERNEL); 4019 if (!reply_buf) { 4020 ret = -ENOMEM; 4021 goto out_err; 4022 } 4023 4024 snapid = cpu_to_le64(CEPH_NOSNAP); 4025 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, 4026 "rbd", "get_parent", 4027 &snapid, sizeof (snapid), 4028 reply_buf, size); 4029 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4030 if (ret < 0) 4031 goto out_err; 4032 4033 p = reply_buf; 4034 end = reply_buf + ret; 4035 ret = -ERANGE; 4036 ceph_decode_64_safe(&p, end, pool_id, out_err); 4037 if (pool_id == CEPH_NOPOOL) { 4038 /* 4039 * Either the parent never existed, or we have 4040 * record of it but the image got flattened so it no 4041 * longer has a parent. When the parent of a 4042 * layered image disappears we immediately set the 4043 * overlap to 0. The effect of this is that all new 4044 * requests will be treated as if the image had no 4045 * parent. 4046 */ 4047 if (rbd_dev->parent_overlap) { 4048 rbd_dev->parent_overlap = 0; 4049 smp_mb(); 4050 rbd_dev_parent_put(rbd_dev); 4051 pr_info("%s: clone image has been flattened\n", 4052 rbd_dev->disk->disk_name); 4053 } 4054 4055 goto out; /* No parent? No problem. */ 4056 } 4057 4058 /* The ceph file layout needs to fit pool id in 32 bits */ 4059 4060 ret = -EIO; 4061 if (pool_id > (u64)U32_MAX) { 4062 rbd_warn(NULL, "parent pool id too large (%llu > %u)\n", 4063 (unsigned long long)pool_id, U32_MAX); 4064 goto out_err; 4065 } 4066 4067 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL); 4068 if (IS_ERR(image_id)) { 4069 ret = PTR_ERR(image_id); 4070 goto out_err; 4071 } 4072 ceph_decode_64_safe(&p, end, snap_id, out_err); 4073 ceph_decode_64_safe(&p, end, overlap, out_err); 4074 4075 /* 4076 * The parent won't change (except when the clone is 4077 * flattened, already handled that). So we only need to 4078 * record the parent spec we have not already done so. 4079 */ 4080 if (!rbd_dev->parent_spec) { 4081 parent_spec->pool_id = pool_id; 4082 parent_spec->image_id = image_id; 4083 parent_spec->snap_id = snap_id; 4084 rbd_dev->parent_spec = parent_spec; 4085 parent_spec = NULL; /* rbd_dev now owns this */ 4086 } 4087 4088 /* 4089 * We always update the parent overlap. If it's zero we 4090 * treat it specially. 4091 */ 4092 rbd_dev->parent_overlap = overlap; 4093 smp_mb(); 4094 if (!overlap) { 4095 4096 /* A null parent_spec indicates it's the initial probe */ 4097 4098 if (parent_spec) { 4099 /* 4100 * The overlap has become zero, so the clone 4101 * must have been resized down to 0 at some 4102 * point. Treat this the same as a flatten. 4103 */ 4104 rbd_dev_parent_put(rbd_dev); 4105 pr_info("%s: clone image now standalone\n", 4106 rbd_dev->disk->disk_name); 4107 } else { 4108 /* 4109 * For the initial probe, if we find the 4110 * overlap is zero we just pretend there was 4111 * no parent image. 4112 */ 4113 rbd_warn(rbd_dev, "ignoring parent of " 4114 "clone with overlap 0\n"); 4115 } 4116 } 4117 out: 4118 ret = 0; 4119 out_err: 4120 kfree(reply_buf); 4121 rbd_spec_put(parent_spec); 4122 4123 return ret; 4124 } 4125 4126 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev) 4127 { 4128 struct { 4129 __le64 stripe_unit; 4130 __le64 stripe_count; 4131 } __attribute__ ((packed)) striping_info_buf = { 0 }; 4132 size_t size = sizeof (striping_info_buf); 4133 void *p; 4134 u64 obj_size; 4135 u64 stripe_unit; 4136 u64 stripe_count; 4137 int ret; 4138 4139 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, 4140 "rbd", "get_stripe_unit_count", NULL, 0, 4141 (char *)&striping_info_buf, size); 4142 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4143 if (ret < 0) 4144 return ret; 4145 if (ret < size) 4146 return -ERANGE; 4147 4148 /* 4149 * We don't actually support the "fancy striping" feature 4150 * (STRIPINGV2) yet, but if the striping sizes are the 4151 * defaults the behavior is the same as before. So find 4152 * out, and only fail if the image has non-default values. 4153 */ 4154 ret = -EINVAL; 4155 obj_size = (u64)1 << rbd_dev->header.obj_order; 4156 p = &striping_info_buf; 4157 stripe_unit = ceph_decode_64(&p); 4158 if (stripe_unit != obj_size) { 4159 rbd_warn(rbd_dev, "unsupported stripe unit " 4160 "(got %llu want %llu)", 4161 stripe_unit, obj_size); 4162 return -EINVAL; 4163 } 4164 stripe_count = ceph_decode_64(&p); 4165 if (stripe_count != 1) { 4166 rbd_warn(rbd_dev, "unsupported stripe count " 4167 "(got %llu want 1)", stripe_count); 4168 return -EINVAL; 4169 } 4170 rbd_dev->header.stripe_unit = stripe_unit; 4171 rbd_dev->header.stripe_count = stripe_count; 4172 4173 return 0; 4174 } 4175 4176 static char *rbd_dev_image_name(struct rbd_device *rbd_dev) 4177 { 4178 size_t image_id_size; 4179 char *image_id; 4180 void *p; 4181 void *end; 4182 size_t size; 4183 void *reply_buf = NULL; 4184 size_t len = 0; 4185 char *image_name = NULL; 4186 int ret; 4187 4188 rbd_assert(!rbd_dev->spec->image_name); 4189 4190 len = strlen(rbd_dev->spec->image_id); 4191 image_id_size = sizeof (__le32) + len; 4192 image_id = kmalloc(image_id_size, GFP_KERNEL); 4193 if (!image_id) 4194 return NULL; 4195 4196 p = image_id; 4197 end = image_id + image_id_size; 4198 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len); 4199 4200 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX; 4201 reply_buf = kmalloc(size, GFP_KERNEL); 4202 if (!reply_buf) 4203 goto out; 4204 4205 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY, 4206 "rbd", "dir_get_name", 4207 image_id, image_id_size, 4208 reply_buf, size); 4209 if (ret < 0) 4210 goto out; 4211 p = reply_buf; 4212 end = reply_buf + ret; 4213 4214 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL); 4215 if (IS_ERR(image_name)) 4216 image_name = NULL; 4217 else 4218 dout("%s: name is %s len is %zd\n", __func__, image_name, len); 4219 out: 4220 kfree(reply_buf); 4221 kfree(image_id); 4222 4223 return image_name; 4224 } 4225 4226 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 4227 { 4228 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 4229 const char *snap_name; 4230 u32 which = 0; 4231 4232 /* Skip over names until we find the one we are looking for */ 4233 4234 snap_name = rbd_dev->header.snap_names; 4235 while (which < snapc->num_snaps) { 4236 if (!strcmp(name, snap_name)) 4237 return snapc->snaps[which]; 4238 snap_name += strlen(snap_name) + 1; 4239 which++; 4240 } 4241 return CEPH_NOSNAP; 4242 } 4243 4244 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 4245 { 4246 struct ceph_snap_context *snapc = rbd_dev->header.snapc; 4247 u32 which; 4248 bool found = false; 4249 u64 snap_id; 4250 4251 for (which = 0; !found && which < snapc->num_snaps; which++) { 4252 const char *snap_name; 4253 4254 snap_id = snapc->snaps[which]; 4255 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id); 4256 if (IS_ERR(snap_name)) { 4257 /* ignore no-longer existing snapshots */ 4258 if (PTR_ERR(snap_name) == -ENOENT) 4259 continue; 4260 else 4261 break; 4262 } 4263 found = !strcmp(name, snap_name); 4264 kfree(snap_name); 4265 } 4266 return found ? snap_id : CEPH_NOSNAP; 4267 } 4268 4269 /* 4270 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if 4271 * no snapshot by that name is found, or if an error occurs. 4272 */ 4273 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) 4274 { 4275 if (rbd_dev->image_format == 1) 4276 return rbd_v1_snap_id_by_name(rbd_dev, name); 4277 4278 return rbd_v2_snap_id_by_name(rbd_dev, name); 4279 } 4280 4281 /* 4282 * When an rbd image has a parent image, it is identified by the 4283 * pool, image, and snapshot ids (not names). This function fills 4284 * in the names for those ids. (It's OK if we can't figure out the 4285 * name for an image id, but the pool and snapshot ids should always 4286 * exist and have names.) All names in an rbd spec are dynamically 4287 * allocated. 4288 * 4289 * When an image being mapped (not a parent) is probed, we have the 4290 * pool name and pool id, image name and image id, and the snapshot 4291 * name. The only thing we're missing is the snapshot id. 4292 */ 4293 static int rbd_dev_spec_update(struct rbd_device *rbd_dev) 4294 { 4295 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; 4296 struct rbd_spec *spec = rbd_dev->spec; 4297 const char *pool_name; 4298 const char *image_name; 4299 const char *snap_name; 4300 int ret; 4301 4302 /* 4303 * An image being mapped will have the pool name (etc.), but 4304 * we need to look up the snapshot id. 4305 */ 4306 if (spec->pool_name) { 4307 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) { 4308 u64 snap_id; 4309 4310 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name); 4311 if (snap_id == CEPH_NOSNAP) 4312 return -ENOENT; 4313 spec->snap_id = snap_id; 4314 } else { 4315 spec->snap_id = CEPH_NOSNAP; 4316 } 4317 4318 return 0; 4319 } 4320 4321 /* Get the pool name; we have to make our own copy of this */ 4322 4323 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id); 4324 if (!pool_name) { 4325 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id); 4326 return -EIO; 4327 } 4328 pool_name = kstrdup(pool_name, GFP_KERNEL); 4329 if (!pool_name) 4330 return -ENOMEM; 4331 4332 /* Fetch the image name; tolerate failure here */ 4333 4334 image_name = rbd_dev_image_name(rbd_dev); 4335 if (!image_name) 4336 rbd_warn(rbd_dev, "unable to get image name"); 4337 4338 /* Look up the snapshot name, and make a copy */ 4339 4340 snap_name = rbd_snap_name(rbd_dev, spec->snap_id); 4341 if (IS_ERR(snap_name)) { 4342 ret = PTR_ERR(snap_name); 4343 goto out_err; 4344 } 4345 4346 spec->pool_name = pool_name; 4347 spec->image_name = image_name; 4348 spec->snap_name = snap_name; 4349 4350 return 0; 4351 out_err: 4352 kfree(image_name); 4353 kfree(pool_name); 4354 4355 return ret; 4356 } 4357 4358 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev) 4359 { 4360 size_t size; 4361 int ret; 4362 void *reply_buf; 4363 void *p; 4364 void *end; 4365 u64 seq; 4366 u32 snap_count; 4367 struct ceph_snap_context *snapc; 4368 u32 i; 4369 4370 /* 4371 * We'll need room for the seq value (maximum snapshot id), 4372 * snapshot count, and array of that many snapshot ids. 4373 * For now we have a fixed upper limit on the number we're 4374 * prepared to receive. 4375 */ 4376 size = sizeof (__le64) + sizeof (__le32) + 4377 RBD_MAX_SNAP_COUNT * sizeof (__le64); 4378 reply_buf = kzalloc(size, GFP_KERNEL); 4379 if (!reply_buf) 4380 return -ENOMEM; 4381 4382 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, 4383 "rbd", "get_snapcontext", NULL, 0, 4384 reply_buf, size); 4385 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4386 if (ret < 0) 4387 goto out; 4388 4389 p = reply_buf; 4390 end = reply_buf + ret; 4391 ret = -ERANGE; 4392 ceph_decode_64_safe(&p, end, seq, out); 4393 ceph_decode_32_safe(&p, end, snap_count, out); 4394 4395 /* 4396 * Make sure the reported number of snapshot ids wouldn't go 4397 * beyond the end of our buffer. But before checking that, 4398 * make sure the computed size of the snapshot context we 4399 * allocate is representable in a size_t. 4400 */ 4401 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context)) 4402 / sizeof (u64)) { 4403 ret = -EINVAL; 4404 goto out; 4405 } 4406 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64))) 4407 goto out; 4408 ret = 0; 4409 4410 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); 4411 if (!snapc) { 4412 ret = -ENOMEM; 4413 goto out; 4414 } 4415 snapc->seq = seq; 4416 for (i = 0; i < snap_count; i++) 4417 snapc->snaps[i] = ceph_decode_64(&p); 4418 4419 ceph_put_snap_context(rbd_dev->header.snapc); 4420 rbd_dev->header.snapc = snapc; 4421 4422 dout(" snap context seq = %llu, snap_count = %u\n", 4423 (unsigned long long)seq, (unsigned int)snap_count); 4424 out: 4425 kfree(reply_buf); 4426 4427 return ret; 4428 } 4429 4430 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, 4431 u64 snap_id) 4432 { 4433 size_t size; 4434 void *reply_buf; 4435 __le64 snapid; 4436 int ret; 4437 void *p; 4438 void *end; 4439 char *snap_name; 4440 4441 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN; 4442 reply_buf = kmalloc(size, GFP_KERNEL); 4443 if (!reply_buf) 4444 return ERR_PTR(-ENOMEM); 4445 4446 snapid = cpu_to_le64(snap_id); 4447 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, 4448 "rbd", "get_snapshot_name", 4449 &snapid, sizeof (snapid), 4450 reply_buf, size); 4451 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4452 if (ret < 0) { 4453 snap_name = ERR_PTR(ret); 4454 goto out; 4455 } 4456 4457 p = reply_buf; 4458 end = reply_buf + ret; 4459 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL); 4460 if (IS_ERR(snap_name)) 4461 goto out; 4462 4463 dout(" snap_id 0x%016llx snap_name = %s\n", 4464 (unsigned long long)snap_id, snap_name); 4465 out: 4466 kfree(reply_buf); 4467 4468 return snap_name; 4469 } 4470 4471 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev) 4472 { 4473 bool first_time = rbd_dev->header.object_prefix == NULL; 4474 int ret; 4475 4476 ret = rbd_dev_v2_image_size(rbd_dev); 4477 if (ret) 4478 return ret; 4479 4480 if (first_time) { 4481 ret = rbd_dev_v2_header_onetime(rbd_dev); 4482 if (ret) 4483 return ret; 4484 } 4485 4486 /* 4487 * If the image supports layering, get the parent info. We 4488 * need to probe the first time regardless. Thereafter we 4489 * only need to if there's a parent, to see if it has 4490 * disappeared due to the mapped image getting flattened. 4491 */ 4492 if (rbd_dev->header.features & RBD_FEATURE_LAYERING && 4493 (first_time || rbd_dev->parent_spec)) { 4494 bool warn; 4495 4496 ret = rbd_dev_v2_parent_info(rbd_dev); 4497 if (ret) 4498 return ret; 4499 4500 /* 4501 * Print a warning if this is the initial probe and 4502 * the image has a parent. Don't print it if the 4503 * image now being probed is itself a parent. We 4504 * can tell at this point because we won't know its 4505 * pool name yet (just its pool id). 4506 */ 4507 warn = rbd_dev->parent_spec && rbd_dev->spec->pool_name; 4508 if (first_time && warn) 4509 rbd_warn(rbd_dev, "WARNING: kernel layering " 4510 "is EXPERIMENTAL!"); 4511 } 4512 4513 if (rbd_dev->spec->snap_id == CEPH_NOSNAP) 4514 if (rbd_dev->mapping.size != rbd_dev->header.image_size) 4515 rbd_dev->mapping.size = rbd_dev->header.image_size; 4516 4517 ret = rbd_dev_v2_snap_context(rbd_dev); 4518 dout("rbd_dev_v2_snap_context returned %d\n", ret); 4519 4520 return ret; 4521 } 4522 4523 static int rbd_bus_add_dev(struct rbd_device *rbd_dev) 4524 { 4525 struct device *dev; 4526 int ret; 4527 4528 dev = &rbd_dev->dev; 4529 dev->bus = &rbd_bus_type; 4530 dev->type = &rbd_device_type; 4531 dev->parent = &rbd_root_dev; 4532 dev->release = rbd_dev_device_release; 4533 dev_set_name(dev, "%d", rbd_dev->dev_id); 4534 ret = device_register(dev); 4535 4536 return ret; 4537 } 4538 4539 static void rbd_bus_del_dev(struct rbd_device *rbd_dev) 4540 { 4541 device_unregister(&rbd_dev->dev); 4542 } 4543 4544 /* 4545 * Get a unique rbd identifier for the given new rbd_dev, and add 4546 * the rbd_dev to the global list. 4547 */ 4548 static int rbd_dev_id_get(struct rbd_device *rbd_dev) 4549 { 4550 int new_dev_id; 4551 4552 new_dev_id = ida_simple_get(&rbd_dev_id_ida, 4553 0, minor_to_rbd_dev_id(1 << MINORBITS), 4554 GFP_KERNEL); 4555 if (new_dev_id < 0) 4556 return new_dev_id; 4557 4558 rbd_dev->dev_id = new_dev_id; 4559 4560 spin_lock(&rbd_dev_list_lock); 4561 list_add_tail(&rbd_dev->node, &rbd_dev_list); 4562 spin_unlock(&rbd_dev_list_lock); 4563 4564 dout("rbd_dev %p given dev id %d\n", rbd_dev, rbd_dev->dev_id); 4565 4566 return 0; 4567 } 4568 4569 /* 4570 * Remove an rbd_dev from the global list, and record that its 4571 * identifier is no longer in use. 4572 */ 4573 static void rbd_dev_id_put(struct rbd_device *rbd_dev) 4574 { 4575 spin_lock(&rbd_dev_list_lock); 4576 list_del_init(&rbd_dev->node); 4577 spin_unlock(&rbd_dev_list_lock); 4578 4579 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); 4580 4581 dout("rbd_dev %p released dev id %d\n", rbd_dev, rbd_dev->dev_id); 4582 } 4583 4584 /* 4585 * Skips over white space at *buf, and updates *buf to point to the 4586 * first found non-space character (if any). Returns the length of 4587 * the token (string of non-white space characters) found. Note 4588 * that *buf must be terminated with '\0'. 4589 */ 4590 static inline size_t next_token(const char **buf) 4591 { 4592 /* 4593 * These are the characters that produce nonzero for 4594 * isspace() in the "C" and "POSIX" locales. 4595 */ 4596 const char *spaces = " \f\n\r\t\v"; 4597 4598 *buf += strspn(*buf, spaces); /* Find start of token */ 4599 4600 return strcspn(*buf, spaces); /* Return token length */ 4601 } 4602 4603 /* 4604 * Finds the next token in *buf, and if the provided token buffer is 4605 * big enough, copies the found token into it. The result, if 4606 * copied, is guaranteed to be terminated with '\0'. Note that *buf 4607 * must be terminated with '\0' on entry. 4608 * 4609 * Returns the length of the token found (not including the '\0'). 4610 * Return value will be 0 if no token is found, and it will be >= 4611 * token_size if the token would not fit. 4612 * 4613 * The *buf pointer will be updated to point beyond the end of the 4614 * found token. Note that this occurs even if the token buffer is 4615 * too small to hold it. 4616 */ 4617 static inline size_t copy_token(const char **buf, 4618 char *token, 4619 size_t token_size) 4620 { 4621 size_t len; 4622 4623 len = next_token(buf); 4624 if (len < token_size) { 4625 memcpy(token, *buf, len); 4626 *(token + len) = '\0'; 4627 } 4628 *buf += len; 4629 4630 return len; 4631 } 4632 4633 /* 4634 * Finds the next token in *buf, dynamically allocates a buffer big 4635 * enough to hold a copy of it, and copies the token into the new 4636 * buffer. The copy is guaranteed to be terminated with '\0'. Note 4637 * that a duplicate buffer is created even for a zero-length token. 4638 * 4639 * Returns a pointer to the newly-allocated duplicate, or a null 4640 * pointer if memory for the duplicate was not available. If 4641 * the lenp argument is a non-null pointer, the length of the token 4642 * (not including the '\0') is returned in *lenp. 4643 * 4644 * If successful, the *buf pointer will be updated to point beyond 4645 * the end of the found token. 4646 * 4647 * Note: uses GFP_KERNEL for allocation. 4648 */ 4649 static inline char *dup_token(const char **buf, size_t *lenp) 4650 { 4651 char *dup; 4652 size_t len; 4653 4654 len = next_token(buf); 4655 dup = kmemdup(*buf, len + 1, GFP_KERNEL); 4656 if (!dup) 4657 return NULL; 4658 *(dup + len) = '\0'; 4659 *buf += len; 4660 4661 if (lenp) 4662 *lenp = len; 4663 4664 return dup; 4665 } 4666 4667 /* 4668 * Parse the options provided for an "rbd add" (i.e., rbd image 4669 * mapping) request. These arrive via a write to /sys/bus/rbd/add, 4670 * and the data written is passed here via a NUL-terminated buffer. 4671 * Returns 0 if successful or an error code otherwise. 4672 * 4673 * The information extracted from these options is recorded in 4674 * the other parameters which return dynamically-allocated 4675 * structures: 4676 * ceph_opts 4677 * The address of a pointer that will refer to a ceph options 4678 * structure. Caller must release the returned pointer using 4679 * ceph_destroy_options() when it is no longer needed. 4680 * rbd_opts 4681 * Address of an rbd options pointer. Fully initialized by 4682 * this function; caller must release with kfree(). 4683 * spec 4684 * Address of an rbd image specification pointer. Fully 4685 * initialized by this function based on parsed options. 4686 * Caller must release with rbd_spec_put(). 4687 * 4688 * The options passed take this form: 4689 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>] 4690 * where: 4691 * <mon_addrs> 4692 * A comma-separated list of one or more monitor addresses. 4693 * A monitor address is an ip address, optionally followed 4694 * by a port number (separated by a colon). 4695 * I.e.: ip1[:port1][,ip2[:port2]...] 4696 * <options> 4697 * A comma-separated list of ceph and/or rbd options. 4698 * <pool_name> 4699 * The name of the rados pool containing the rbd image. 4700 * <image_name> 4701 * The name of the image in that pool to map. 4702 * <snap_id> 4703 * An optional snapshot id. If provided, the mapping will 4704 * present data from the image at the time that snapshot was 4705 * created. The image head is used if no snapshot id is 4706 * provided. Snapshot mappings are always read-only. 4707 */ 4708 static int rbd_add_parse_args(const char *buf, 4709 struct ceph_options **ceph_opts, 4710 struct rbd_options **opts, 4711 struct rbd_spec **rbd_spec) 4712 { 4713 size_t len; 4714 char *options; 4715 const char *mon_addrs; 4716 char *snap_name; 4717 size_t mon_addrs_size; 4718 struct rbd_spec *spec = NULL; 4719 struct rbd_options *rbd_opts = NULL; 4720 struct ceph_options *copts; 4721 int ret; 4722 4723 /* The first four tokens are required */ 4724 4725 len = next_token(&buf); 4726 if (!len) { 4727 rbd_warn(NULL, "no monitor address(es) provided"); 4728 return -EINVAL; 4729 } 4730 mon_addrs = buf; 4731 mon_addrs_size = len + 1; 4732 buf += len; 4733 4734 ret = -EINVAL; 4735 options = dup_token(&buf, NULL); 4736 if (!options) 4737 return -ENOMEM; 4738 if (!*options) { 4739 rbd_warn(NULL, "no options provided"); 4740 goto out_err; 4741 } 4742 4743 spec = rbd_spec_alloc(); 4744 if (!spec) 4745 goto out_mem; 4746 4747 spec->pool_name = dup_token(&buf, NULL); 4748 if (!spec->pool_name) 4749 goto out_mem; 4750 if (!*spec->pool_name) { 4751 rbd_warn(NULL, "no pool name provided"); 4752 goto out_err; 4753 } 4754 4755 spec->image_name = dup_token(&buf, NULL); 4756 if (!spec->image_name) 4757 goto out_mem; 4758 if (!*spec->image_name) { 4759 rbd_warn(NULL, "no image name provided"); 4760 goto out_err; 4761 } 4762 4763 /* 4764 * Snapshot name is optional; default is to use "-" 4765 * (indicating the head/no snapshot). 4766 */ 4767 len = next_token(&buf); 4768 if (!len) { 4769 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */ 4770 len = sizeof (RBD_SNAP_HEAD_NAME) - 1; 4771 } else if (len > RBD_MAX_SNAP_NAME_LEN) { 4772 ret = -ENAMETOOLONG; 4773 goto out_err; 4774 } 4775 snap_name = kmemdup(buf, len + 1, GFP_KERNEL); 4776 if (!snap_name) 4777 goto out_mem; 4778 *(snap_name + len) = '\0'; 4779 spec->snap_name = snap_name; 4780 4781 /* Initialize all rbd options to the defaults */ 4782 4783 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL); 4784 if (!rbd_opts) 4785 goto out_mem; 4786 4787 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT; 4788 4789 copts = ceph_parse_options(options, mon_addrs, 4790 mon_addrs + mon_addrs_size - 1, 4791 parse_rbd_opts_token, rbd_opts); 4792 if (IS_ERR(copts)) { 4793 ret = PTR_ERR(copts); 4794 goto out_err; 4795 } 4796 kfree(options); 4797 4798 *ceph_opts = copts; 4799 *opts = rbd_opts; 4800 *rbd_spec = spec; 4801 4802 return 0; 4803 out_mem: 4804 ret = -ENOMEM; 4805 out_err: 4806 kfree(rbd_opts); 4807 rbd_spec_put(spec); 4808 kfree(options); 4809 4810 return ret; 4811 } 4812 4813 /* 4814 * Return pool id (>= 0) or a negative error code. 4815 */ 4816 static int rbd_add_get_pool_id(struct rbd_client *rbdc, const char *pool_name) 4817 { 4818 u64 newest_epoch; 4819 unsigned long timeout = rbdc->client->options->mount_timeout * HZ; 4820 int tries = 0; 4821 int ret; 4822 4823 again: 4824 ret = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, pool_name); 4825 if (ret == -ENOENT && tries++ < 1) { 4826 ret = ceph_monc_do_get_version(&rbdc->client->monc, "osdmap", 4827 &newest_epoch); 4828 if (ret < 0) 4829 return ret; 4830 4831 if (rbdc->client->osdc.osdmap->epoch < newest_epoch) { 4832 ceph_monc_request_next_osdmap(&rbdc->client->monc); 4833 (void) ceph_monc_wait_osdmap(&rbdc->client->monc, 4834 newest_epoch, timeout); 4835 goto again; 4836 } else { 4837 /* the osdmap we have is new enough */ 4838 return -ENOENT; 4839 } 4840 } 4841 4842 return ret; 4843 } 4844 4845 /* 4846 * An rbd format 2 image has a unique identifier, distinct from the 4847 * name given to it by the user. Internally, that identifier is 4848 * what's used to specify the names of objects related to the image. 4849 * 4850 * A special "rbd id" object is used to map an rbd image name to its 4851 * id. If that object doesn't exist, then there is no v2 rbd image 4852 * with the supplied name. 4853 * 4854 * This function will record the given rbd_dev's image_id field if 4855 * it can be determined, and in that case will return 0. If any 4856 * errors occur a negative errno will be returned and the rbd_dev's 4857 * image_id field will be unchanged (and should be NULL). 4858 */ 4859 static int rbd_dev_image_id(struct rbd_device *rbd_dev) 4860 { 4861 int ret; 4862 size_t size; 4863 char *object_name; 4864 void *response; 4865 char *image_id; 4866 4867 /* 4868 * When probing a parent image, the image id is already 4869 * known (and the image name likely is not). There's no 4870 * need to fetch the image id again in this case. We 4871 * do still need to set the image format though. 4872 */ 4873 if (rbd_dev->spec->image_id) { 4874 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1; 4875 4876 return 0; 4877 } 4878 4879 /* 4880 * First, see if the format 2 image id file exists, and if 4881 * so, get the image's persistent id from it. 4882 */ 4883 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name); 4884 object_name = kmalloc(size, GFP_NOIO); 4885 if (!object_name) 4886 return -ENOMEM; 4887 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name); 4888 dout("rbd id object name is %s\n", object_name); 4889 4890 /* Response will be an encoded string, which includes a length */ 4891 4892 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX; 4893 response = kzalloc(size, GFP_NOIO); 4894 if (!response) { 4895 ret = -ENOMEM; 4896 goto out; 4897 } 4898 4899 /* If it doesn't exist we'll assume it's a format 1 image */ 4900 4901 ret = rbd_obj_method_sync(rbd_dev, object_name, 4902 "rbd", "get_id", NULL, 0, 4903 response, RBD_IMAGE_ID_LEN_MAX); 4904 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); 4905 if (ret == -ENOENT) { 4906 image_id = kstrdup("", GFP_KERNEL); 4907 ret = image_id ? 0 : -ENOMEM; 4908 if (!ret) 4909 rbd_dev->image_format = 1; 4910 } else if (ret > sizeof (__le32)) { 4911 void *p = response; 4912 4913 image_id = ceph_extract_encoded_string(&p, p + ret, 4914 NULL, GFP_NOIO); 4915 ret = PTR_ERR_OR_ZERO(image_id); 4916 if (!ret) 4917 rbd_dev->image_format = 2; 4918 } else { 4919 ret = -EINVAL; 4920 } 4921 4922 if (!ret) { 4923 rbd_dev->spec->image_id = image_id; 4924 dout("image_id is %s\n", image_id); 4925 } 4926 out: 4927 kfree(response); 4928 kfree(object_name); 4929 4930 return ret; 4931 } 4932 4933 /* 4934 * Undo whatever state changes are made by v1 or v2 header info 4935 * call. 4936 */ 4937 static void rbd_dev_unprobe(struct rbd_device *rbd_dev) 4938 { 4939 struct rbd_image_header *header; 4940 4941 /* Drop parent reference unless it's already been done (or none) */ 4942 4943 if (rbd_dev->parent_overlap) 4944 rbd_dev_parent_put(rbd_dev); 4945 4946 /* Free dynamic fields from the header, then zero it out */ 4947 4948 header = &rbd_dev->header; 4949 ceph_put_snap_context(header->snapc); 4950 kfree(header->snap_sizes); 4951 kfree(header->snap_names); 4952 kfree(header->object_prefix); 4953 memset(header, 0, sizeof (*header)); 4954 } 4955 4956 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev) 4957 { 4958 int ret; 4959 4960 ret = rbd_dev_v2_object_prefix(rbd_dev); 4961 if (ret) 4962 goto out_err; 4963 4964 /* 4965 * Get the and check features for the image. Currently the 4966 * features are assumed to never change. 4967 */ 4968 ret = rbd_dev_v2_features(rbd_dev); 4969 if (ret) 4970 goto out_err; 4971 4972 /* If the image supports fancy striping, get its parameters */ 4973 4974 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) { 4975 ret = rbd_dev_v2_striping_info(rbd_dev); 4976 if (ret < 0) 4977 goto out_err; 4978 } 4979 /* No support for crypto and compression type format 2 images */ 4980 4981 return 0; 4982 out_err: 4983 rbd_dev->header.features = 0; 4984 kfree(rbd_dev->header.object_prefix); 4985 rbd_dev->header.object_prefix = NULL; 4986 4987 return ret; 4988 } 4989 4990 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev) 4991 { 4992 struct rbd_device *parent = NULL; 4993 struct rbd_spec *parent_spec; 4994 struct rbd_client *rbdc; 4995 int ret; 4996 4997 if (!rbd_dev->parent_spec) 4998 return 0; 4999 /* 5000 * We need to pass a reference to the client and the parent 5001 * spec when creating the parent rbd_dev. Images related by 5002 * parent/child relationships always share both. 5003 */ 5004 parent_spec = rbd_spec_get(rbd_dev->parent_spec); 5005 rbdc = __rbd_get_client(rbd_dev->rbd_client); 5006 5007 ret = -ENOMEM; 5008 parent = rbd_dev_create(rbdc, parent_spec); 5009 if (!parent) 5010 goto out_err; 5011 5012 ret = rbd_dev_image_probe(parent, false); 5013 if (ret < 0) 5014 goto out_err; 5015 rbd_dev->parent = parent; 5016 atomic_set(&rbd_dev->parent_ref, 1); 5017 5018 return 0; 5019 out_err: 5020 if (parent) { 5021 rbd_dev_unparent(rbd_dev); 5022 kfree(rbd_dev->header_name); 5023 rbd_dev_destroy(parent); 5024 } else { 5025 rbd_put_client(rbdc); 5026 rbd_spec_put(parent_spec); 5027 } 5028 5029 return ret; 5030 } 5031 5032 static int rbd_dev_device_setup(struct rbd_device *rbd_dev) 5033 { 5034 int ret; 5035 5036 /* Get an id and fill in device name. */ 5037 5038 ret = rbd_dev_id_get(rbd_dev); 5039 if (ret) 5040 return ret; 5041 5042 BUILD_BUG_ON(DEV_NAME_LEN 5043 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH); 5044 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id); 5045 5046 /* Record our major and minor device numbers. */ 5047 5048 if (!single_major) { 5049 ret = register_blkdev(0, rbd_dev->name); 5050 if (ret < 0) 5051 goto err_out_id; 5052 5053 rbd_dev->major = ret; 5054 rbd_dev->minor = 0; 5055 } else { 5056 rbd_dev->major = rbd_major; 5057 rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id); 5058 } 5059 5060 /* Set up the blkdev mapping. */ 5061 5062 ret = rbd_init_disk(rbd_dev); 5063 if (ret) 5064 goto err_out_blkdev; 5065 5066 ret = rbd_dev_mapping_set(rbd_dev); 5067 if (ret) 5068 goto err_out_disk; 5069 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE); 5070 set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only); 5071 5072 ret = rbd_bus_add_dev(rbd_dev); 5073 if (ret) 5074 goto err_out_mapping; 5075 5076 /* Everything's ready. Announce the disk to the world. */ 5077 5078 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); 5079 add_disk(rbd_dev->disk); 5080 5081 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name, 5082 (unsigned long long) rbd_dev->mapping.size); 5083 5084 return ret; 5085 5086 err_out_mapping: 5087 rbd_dev_mapping_clear(rbd_dev); 5088 err_out_disk: 5089 rbd_free_disk(rbd_dev); 5090 err_out_blkdev: 5091 if (!single_major) 5092 unregister_blkdev(rbd_dev->major, rbd_dev->name); 5093 err_out_id: 5094 rbd_dev_id_put(rbd_dev); 5095 rbd_dev_mapping_clear(rbd_dev); 5096 5097 return ret; 5098 } 5099 5100 static int rbd_dev_header_name(struct rbd_device *rbd_dev) 5101 { 5102 struct rbd_spec *spec = rbd_dev->spec; 5103 size_t size; 5104 5105 /* Record the header object name for this rbd image. */ 5106 5107 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 5108 5109 if (rbd_dev->image_format == 1) 5110 size = strlen(spec->image_name) + sizeof (RBD_SUFFIX); 5111 else 5112 size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id); 5113 5114 rbd_dev->header_name = kmalloc(size, GFP_KERNEL); 5115 if (!rbd_dev->header_name) 5116 return -ENOMEM; 5117 5118 if (rbd_dev->image_format == 1) 5119 sprintf(rbd_dev->header_name, "%s%s", 5120 spec->image_name, RBD_SUFFIX); 5121 else 5122 sprintf(rbd_dev->header_name, "%s%s", 5123 RBD_HEADER_PREFIX, spec->image_id); 5124 return 0; 5125 } 5126 5127 static void rbd_dev_image_release(struct rbd_device *rbd_dev) 5128 { 5129 rbd_dev_unprobe(rbd_dev); 5130 kfree(rbd_dev->header_name); 5131 rbd_dev->header_name = NULL; 5132 rbd_dev->image_format = 0; 5133 kfree(rbd_dev->spec->image_id); 5134 rbd_dev->spec->image_id = NULL; 5135 5136 rbd_dev_destroy(rbd_dev); 5137 } 5138 5139 /* 5140 * Probe for the existence of the header object for the given rbd 5141 * device. If this image is the one being mapped (i.e., not a 5142 * parent), initiate a watch on its header object before using that 5143 * object to get detailed information about the rbd image. 5144 */ 5145 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping) 5146 { 5147 int ret; 5148 5149 /* 5150 * Get the id from the image id object. Unless there's an 5151 * error, rbd_dev->spec->image_id will be filled in with 5152 * a dynamically-allocated string, and rbd_dev->image_format 5153 * will be set to either 1 or 2. 5154 */ 5155 ret = rbd_dev_image_id(rbd_dev); 5156 if (ret) 5157 return ret; 5158 rbd_assert(rbd_dev->spec->image_id); 5159 rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); 5160 5161 ret = rbd_dev_header_name(rbd_dev); 5162 if (ret) 5163 goto err_out_format; 5164 5165 if (mapping) { 5166 ret = rbd_dev_header_watch_sync(rbd_dev); 5167 if (ret) 5168 goto out_header_name; 5169 } 5170 5171 if (rbd_dev->image_format == 1) 5172 ret = rbd_dev_v1_header_info(rbd_dev); 5173 else 5174 ret = rbd_dev_v2_header_info(rbd_dev); 5175 if (ret) 5176 goto err_out_watch; 5177 5178 ret = rbd_dev_spec_update(rbd_dev); 5179 if (ret) 5180 goto err_out_probe; 5181 5182 ret = rbd_dev_probe_parent(rbd_dev); 5183 if (ret) 5184 goto err_out_probe; 5185 5186 dout("discovered format %u image, header name is %s\n", 5187 rbd_dev->image_format, rbd_dev->header_name); 5188 5189 return 0; 5190 err_out_probe: 5191 rbd_dev_unprobe(rbd_dev); 5192 err_out_watch: 5193 if (mapping) 5194 rbd_dev_header_unwatch_sync(rbd_dev); 5195 out_header_name: 5196 kfree(rbd_dev->header_name); 5197 rbd_dev->header_name = NULL; 5198 err_out_format: 5199 rbd_dev->image_format = 0; 5200 kfree(rbd_dev->spec->image_id); 5201 rbd_dev->spec->image_id = NULL; 5202 5203 dout("probe failed, returning %d\n", ret); 5204 5205 return ret; 5206 } 5207 5208 static ssize_t do_rbd_add(struct bus_type *bus, 5209 const char *buf, 5210 size_t count) 5211 { 5212 struct rbd_device *rbd_dev = NULL; 5213 struct ceph_options *ceph_opts = NULL; 5214 struct rbd_options *rbd_opts = NULL; 5215 struct rbd_spec *spec = NULL; 5216 struct rbd_client *rbdc; 5217 bool read_only; 5218 int rc = -ENOMEM; 5219 5220 if (!try_module_get(THIS_MODULE)) 5221 return -ENODEV; 5222 5223 /* parse add command */ 5224 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec); 5225 if (rc < 0) 5226 goto err_out_module; 5227 read_only = rbd_opts->read_only; 5228 kfree(rbd_opts); 5229 rbd_opts = NULL; /* done with this */ 5230 5231 rbdc = rbd_get_client(ceph_opts); 5232 if (IS_ERR(rbdc)) { 5233 rc = PTR_ERR(rbdc); 5234 goto err_out_args; 5235 } 5236 5237 /* pick the pool */ 5238 rc = rbd_add_get_pool_id(rbdc, spec->pool_name); 5239 if (rc < 0) 5240 goto err_out_client; 5241 spec->pool_id = (u64)rc; 5242 5243 /* The ceph file layout needs to fit pool id in 32 bits */ 5244 5245 if (spec->pool_id > (u64)U32_MAX) { 5246 rbd_warn(NULL, "pool id too large (%llu > %u)\n", 5247 (unsigned long long)spec->pool_id, U32_MAX); 5248 rc = -EIO; 5249 goto err_out_client; 5250 } 5251 5252 rbd_dev = rbd_dev_create(rbdc, spec); 5253 if (!rbd_dev) 5254 goto err_out_client; 5255 rbdc = NULL; /* rbd_dev now owns this */ 5256 spec = NULL; /* rbd_dev now owns this */ 5257 5258 rc = rbd_dev_image_probe(rbd_dev, true); 5259 if (rc < 0) 5260 goto err_out_rbd_dev; 5261 5262 /* If we are mapping a snapshot it must be marked read-only */ 5263 5264 if (rbd_dev->spec->snap_id != CEPH_NOSNAP) 5265 read_only = true; 5266 rbd_dev->mapping.read_only = read_only; 5267 5268 rc = rbd_dev_device_setup(rbd_dev); 5269 if (rc) { 5270 /* 5271 * rbd_dev_header_unwatch_sync() can't be moved into 5272 * rbd_dev_image_release() without refactoring, see 5273 * commit 1f3ef78861ac. 5274 */ 5275 rbd_dev_header_unwatch_sync(rbd_dev); 5276 rbd_dev_image_release(rbd_dev); 5277 goto err_out_module; 5278 } 5279 5280 return count; 5281 5282 err_out_rbd_dev: 5283 rbd_dev_destroy(rbd_dev); 5284 err_out_client: 5285 rbd_put_client(rbdc); 5286 err_out_args: 5287 rbd_spec_put(spec); 5288 err_out_module: 5289 module_put(THIS_MODULE); 5290 5291 dout("Error adding device %s\n", buf); 5292 5293 return (ssize_t)rc; 5294 } 5295 5296 static ssize_t rbd_add(struct bus_type *bus, 5297 const char *buf, 5298 size_t count) 5299 { 5300 if (single_major) 5301 return -EINVAL; 5302 5303 return do_rbd_add(bus, buf, count); 5304 } 5305 5306 static ssize_t rbd_add_single_major(struct bus_type *bus, 5307 const char *buf, 5308 size_t count) 5309 { 5310 return do_rbd_add(bus, buf, count); 5311 } 5312 5313 static void rbd_dev_device_release(struct device *dev) 5314 { 5315 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); 5316 5317 rbd_free_disk(rbd_dev); 5318 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); 5319 rbd_dev_mapping_clear(rbd_dev); 5320 if (!single_major) 5321 unregister_blkdev(rbd_dev->major, rbd_dev->name); 5322 rbd_dev_id_put(rbd_dev); 5323 rbd_dev_mapping_clear(rbd_dev); 5324 } 5325 5326 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev) 5327 { 5328 while (rbd_dev->parent) { 5329 struct rbd_device *first = rbd_dev; 5330 struct rbd_device *second = first->parent; 5331 struct rbd_device *third; 5332 5333 /* 5334 * Follow to the parent with no grandparent and 5335 * remove it. 5336 */ 5337 while (second && (third = second->parent)) { 5338 first = second; 5339 second = third; 5340 } 5341 rbd_assert(second); 5342 rbd_dev_image_release(second); 5343 first->parent = NULL; 5344 first->parent_overlap = 0; 5345 5346 rbd_assert(first->parent_spec); 5347 rbd_spec_put(first->parent_spec); 5348 first->parent_spec = NULL; 5349 } 5350 } 5351 5352 static ssize_t do_rbd_remove(struct bus_type *bus, 5353 const char *buf, 5354 size_t count) 5355 { 5356 struct rbd_device *rbd_dev = NULL; 5357 struct list_head *tmp; 5358 int dev_id; 5359 unsigned long ul; 5360 bool already = false; 5361 int ret; 5362 5363 ret = kstrtoul(buf, 10, &ul); 5364 if (ret) 5365 return ret; 5366 5367 /* convert to int; abort if we lost anything in the conversion */ 5368 dev_id = (int)ul; 5369 if (dev_id != ul) 5370 return -EINVAL; 5371 5372 ret = -ENOENT; 5373 spin_lock(&rbd_dev_list_lock); 5374 list_for_each(tmp, &rbd_dev_list) { 5375 rbd_dev = list_entry(tmp, struct rbd_device, node); 5376 if (rbd_dev->dev_id == dev_id) { 5377 ret = 0; 5378 break; 5379 } 5380 } 5381 if (!ret) { 5382 spin_lock_irq(&rbd_dev->lock); 5383 if (rbd_dev->open_count) 5384 ret = -EBUSY; 5385 else 5386 already = test_and_set_bit(RBD_DEV_FLAG_REMOVING, 5387 &rbd_dev->flags); 5388 spin_unlock_irq(&rbd_dev->lock); 5389 } 5390 spin_unlock(&rbd_dev_list_lock); 5391 if (ret < 0 || already) 5392 return ret; 5393 5394 rbd_dev_header_unwatch_sync(rbd_dev); 5395 /* 5396 * flush remaining watch callbacks - these must be complete 5397 * before the osd_client is shutdown 5398 */ 5399 dout("%s: flushing notifies", __func__); 5400 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc); 5401 5402 /* 5403 * Don't free anything from rbd_dev->disk until after all 5404 * notifies are completely processed. Otherwise 5405 * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting 5406 * in a potential use after free of rbd_dev->disk or rbd_dev. 5407 */ 5408 rbd_bus_del_dev(rbd_dev); 5409 rbd_dev_image_release(rbd_dev); 5410 module_put(THIS_MODULE); 5411 5412 return count; 5413 } 5414 5415 static ssize_t rbd_remove(struct bus_type *bus, 5416 const char *buf, 5417 size_t count) 5418 { 5419 if (single_major) 5420 return -EINVAL; 5421 5422 return do_rbd_remove(bus, buf, count); 5423 } 5424 5425 static ssize_t rbd_remove_single_major(struct bus_type *bus, 5426 const char *buf, 5427 size_t count) 5428 { 5429 return do_rbd_remove(bus, buf, count); 5430 } 5431 5432 /* 5433 * create control files in sysfs 5434 * /sys/bus/rbd/... 5435 */ 5436 static int rbd_sysfs_init(void) 5437 { 5438 int ret; 5439 5440 ret = device_register(&rbd_root_dev); 5441 if (ret < 0) 5442 return ret; 5443 5444 ret = bus_register(&rbd_bus_type); 5445 if (ret < 0) 5446 device_unregister(&rbd_root_dev); 5447 5448 return ret; 5449 } 5450 5451 static void rbd_sysfs_cleanup(void) 5452 { 5453 bus_unregister(&rbd_bus_type); 5454 device_unregister(&rbd_root_dev); 5455 } 5456 5457 static int rbd_slab_init(void) 5458 { 5459 rbd_assert(!rbd_img_request_cache); 5460 rbd_img_request_cache = kmem_cache_create("rbd_img_request", 5461 sizeof (struct rbd_img_request), 5462 __alignof__(struct rbd_img_request), 5463 0, NULL); 5464 if (!rbd_img_request_cache) 5465 return -ENOMEM; 5466 5467 rbd_assert(!rbd_obj_request_cache); 5468 rbd_obj_request_cache = kmem_cache_create("rbd_obj_request", 5469 sizeof (struct rbd_obj_request), 5470 __alignof__(struct rbd_obj_request), 5471 0, NULL); 5472 if (!rbd_obj_request_cache) 5473 goto out_err; 5474 5475 rbd_assert(!rbd_segment_name_cache); 5476 rbd_segment_name_cache = kmem_cache_create("rbd_segment_name", 5477 CEPH_MAX_OID_NAME_LEN + 1, 1, 0, NULL); 5478 if (rbd_segment_name_cache) 5479 return 0; 5480 out_err: 5481 if (rbd_obj_request_cache) { 5482 kmem_cache_destroy(rbd_obj_request_cache); 5483 rbd_obj_request_cache = NULL; 5484 } 5485 5486 kmem_cache_destroy(rbd_img_request_cache); 5487 rbd_img_request_cache = NULL; 5488 5489 return -ENOMEM; 5490 } 5491 5492 static void rbd_slab_exit(void) 5493 { 5494 rbd_assert(rbd_segment_name_cache); 5495 kmem_cache_destroy(rbd_segment_name_cache); 5496 rbd_segment_name_cache = NULL; 5497 5498 rbd_assert(rbd_obj_request_cache); 5499 kmem_cache_destroy(rbd_obj_request_cache); 5500 rbd_obj_request_cache = NULL; 5501 5502 rbd_assert(rbd_img_request_cache); 5503 kmem_cache_destroy(rbd_img_request_cache); 5504 rbd_img_request_cache = NULL; 5505 } 5506 5507 static int __init rbd_init(void) 5508 { 5509 int rc; 5510 5511 if (!libceph_compatible(NULL)) { 5512 rbd_warn(NULL, "libceph incompatibility (quitting)"); 5513 return -EINVAL; 5514 } 5515 5516 rc = rbd_slab_init(); 5517 if (rc) 5518 return rc; 5519 5520 if (single_major) { 5521 rbd_major = register_blkdev(0, RBD_DRV_NAME); 5522 if (rbd_major < 0) { 5523 rc = rbd_major; 5524 goto err_out_slab; 5525 } 5526 } 5527 5528 rc = rbd_sysfs_init(); 5529 if (rc) 5530 goto err_out_blkdev; 5531 5532 if (single_major) 5533 pr_info("loaded (major %d)\n", rbd_major); 5534 else 5535 pr_info("loaded\n"); 5536 5537 return 0; 5538 5539 err_out_blkdev: 5540 if (single_major) 5541 unregister_blkdev(rbd_major, RBD_DRV_NAME); 5542 err_out_slab: 5543 rbd_slab_exit(); 5544 return rc; 5545 } 5546 5547 static void __exit rbd_exit(void) 5548 { 5549 ida_destroy(&rbd_dev_id_ida); 5550 rbd_sysfs_cleanup(); 5551 if (single_major) 5552 unregister_blkdev(rbd_major, RBD_DRV_NAME); 5553 rbd_slab_exit(); 5554 } 5555 5556 module_init(rbd_init); 5557 module_exit(rbd_exit); 5558 5559 MODULE_AUTHOR("Alex Elder <elder@inktank.com>"); 5560 MODULE_AUTHOR("Sage Weil <sage@newdream.net>"); 5561 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>"); 5562 /* following authorship retained from original osdblk.c */ 5563 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>"); 5564 5565 MODULE_DESCRIPTION("RADOS Block Device (RBD) driver"); 5566 MODULE_LICENSE("GPL"); 5567