1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2007 Oracle. All rights reserved. 4 */ 5 6 #include <linux/sched.h> 7 #include <linux/bio.h> 8 #include <linux/slab.h> 9 #include <linux/blkdev.h> 10 #include <linux/ratelimit.h> 11 #include <linux/kthread.h> 12 #include <linux/raid/pq.h> 13 #include <linux/semaphore.h> 14 #include <linux/uuid.h> 15 #include <linux/list_sort.h> 16 #include "misc.h" 17 #include "ctree.h" 18 #include "extent_map.h" 19 #include "disk-io.h" 20 #include "transaction.h" 21 #include "print-tree.h" 22 #include "volumes.h" 23 #include "raid56.h" 24 #include "async-thread.h" 25 #include "check-integrity.h" 26 #include "rcu-string.h" 27 #include "dev-replace.h" 28 #include "sysfs.h" 29 #include "tree-checker.h" 30 #include "space-info.h" 31 #include "block-group.h" 32 #include "discard.h" 33 34 const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { 35 [BTRFS_RAID_RAID10] = { 36 .sub_stripes = 2, 37 .dev_stripes = 1, 38 .devs_max = 0, /* 0 == as many as possible */ 39 .devs_min = 4, 40 .tolerated_failures = 1, 41 .devs_increment = 2, 42 .ncopies = 2, 43 .nparity = 0, 44 .raid_name = "raid10", 45 .bg_flag = BTRFS_BLOCK_GROUP_RAID10, 46 .mindev_error = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET, 47 }, 48 [BTRFS_RAID_RAID1] = { 49 .sub_stripes = 1, 50 .dev_stripes = 1, 51 .devs_max = 2, 52 .devs_min = 2, 53 .tolerated_failures = 1, 54 .devs_increment = 2, 55 .ncopies = 2, 56 .nparity = 0, 57 .raid_name = "raid1", 58 .bg_flag = BTRFS_BLOCK_GROUP_RAID1, 59 .mindev_error = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET, 60 }, 61 [BTRFS_RAID_RAID1C3] = { 62 .sub_stripes = 1, 63 .dev_stripes = 1, 64 .devs_max = 3, 65 .devs_min = 3, 66 .tolerated_failures = 2, 67 .devs_increment = 3, 68 .ncopies = 3, 69 .nparity = 0, 70 .raid_name = "raid1c3", 71 .bg_flag = BTRFS_BLOCK_GROUP_RAID1C3, 72 .mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET, 73 }, 74 [BTRFS_RAID_RAID1C4] = { 75 .sub_stripes = 1, 76 .dev_stripes = 1, 77 .devs_max = 4, 78 .devs_min = 4, 79 .tolerated_failures = 3, 80 .devs_increment = 4, 81 .ncopies = 4, 82 .nparity = 0, 83 .raid_name = "raid1c4", 84 .bg_flag = BTRFS_BLOCK_GROUP_RAID1C4, 85 .mindev_error = BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET, 86 }, 87 [BTRFS_RAID_DUP] = { 88 .sub_stripes = 1, 89 .dev_stripes = 2, 90 .devs_max = 1, 91 .devs_min = 1, 92 .tolerated_failures = 0, 93 .devs_increment = 1, 94 .ncopies = 2, 95 .nparity = 0, 96 .raid_name = "dup", 97 .bg_flag = BTRFS_BLOCK_GROUP_DUP, 98 .mindev_error = 0, 99 }, 100 [BTRFS_RAID_RAID0] = { 101 .sub_stripes = 1, 102 .dev_stripes = 1, 103 .devs_max = 0, 104 .devs_min = 2, 105 .tolerated_failures = 0, 106 .devs_increment = 1, 107 .ncopies = 1, 108 .nparity = 0, 109 .raid_name = "raid0", 110 .bg_flag = BTRFS_BLOCK_GROUP_RAID0, 111 .mindev_error = 0, 112 }, 113 [BTRFS_RAID_SINGLE] = { 114 .sub_stripes = 1, 115 .dev_stripes = 1, 116 .devs_max = 1, 117 .devs_min = 1, 118 .tolerated_failures = 0, 119 .devs_increment = 1, 120 .ncopies = 1, 121 .nparity = 0, 122 .raid_name = "single", 123 .bg_flag = 0, 124 .mindev_error = 0, 125 }, 126 [BTRFS_RAID_RAID5] = { 127 .sub_stripes = 1, 128 .dev_stripes = 1, 129 .devs_max = 0, 130 .devs_min = 2, 131 .tolerated_failures = 1, 132 .devs_increment = 1, 133 .ncopies = 1, 134 .nparity = 1, 135 .raid_name = "raid5", 136 .bg_flag = BTRFS_BLOCK_GROUP_RAID5, 137 .mindev_error = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET, 138 }, 139 [BTRFS_RAID_RAID6] = { 140 .sub_stripes = 1, 141 .dev_stripes = 1, 142 .devs_max = 0, 143 .devs_min = 3, 144 .tolerated_failures = 2, 145 .devs_increment = 1, 146 .ncopies = 1, 147 .nparity = 2, 148 .raid_name = "raid6", 149 .bg_flag = BTRFS_BLOCK_GROUP_RAID6, 150 .mindev_error = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET, 151 }, 152 }; 153 154 const char *btrfs_bg_type_to_raid_name(u64 flags) 155 { 156 const int index = btrfs_bg_flags_to_raid_index(flags); 157 158 if (index >= BTRFS_NR_RAID_TYPES) 159 return NULL; 160 161 return btrfs_raid_array[index].raid_name; 162 } 163 164 /* 165 * Fill @buf with textual description of @bg_flags, no more than @size_buf 166 * bytes including terminating null byte. 167 */ 168 void btrfs_describe_block_groups(u64 bg_flags, char *buf, u32 size_buf) 169 { 170 int i; 171 int ret; 172 char *bp = buf; 173 u64 flags = bg_flags; 174 u32 size_bp = size_buf; 175 176 if (!flags) { 177 strcpy(bp, "NONE"); 178 return; 179 } 180 181 #define DESCRIBE_FLAG(flag, desc) \ 182 do { \ 183 if (flags & (flag)) { \ 184 ret = snprintf(bp, size_bp, "%s|", (desc)); \ 185 if (ret < 0 || ret >= size_bp) \ 186 goto out_overflow; \ 187 size_bp -= ret; \ 188 bp += ret; \ 189 flags &= ~(flag); \ 190 } \ 191 } while (0) 192 193 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_DATA, "data"); 194 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_SYSTEM, "system"); 195 DESCRIBE_FLAG(BTRFS_BLOCK_GROUP_METADATA, "metadata"); 196 197 DESCRIBE_FLAG(BTRFS_AVAIL_ALLOC_BIT_SINGLE, "single"); 198 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) 199 DESCRIBE_FLAG(btrfs_raid_array[i].bg_flag, 200 btrfs_raid_array[i].raid_name); 201 #undef DESCRIBE_FLAG 202 203 if (flags) { 204 ret = snprintf(bp, size_bp, "0x%llx|", flags); 205 size_bp -= ret; 206 } 207 208 if (size_bp < size_buf) 209 buf[size_buf - size_bp - 1] = '\0'; /* remove last | */ 210 211 /* 212 * The text is trimmed, it's up to the caller to provide sufficiently 213 * large buffer 214 */ 215 out_overflow:; 216 } 217 218 static int init_first_rw_device(struct btrfs_trans_handle *trans); 219 static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info); 220 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev); 221 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); 222 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 223 enum btrfs_map_op op, 224 u64 logical, u64 *length, 225 struct btrfs_bio **bbio_ret, 226 int mirror_num, int need_raid_map); 227 228 /* 229 * Device locking 230 * ============== 231 * 232 * There are several mutexes that protect manipulation of devices and low-level 233 * structures like chunks but not block groups, extents or files 234 * 235 * uuid_mutex (global lock) 236 * ------------------------ 237 * protects the fs_uuids list that tracks all per-fs fs_devices, resulting from 238 * the SCAN_DEV ioctl registration or from mount either implicitly (the first 239 * device) or requested by the device= mount option 240 * 241 * the mutex can be very coarse and can cover long-running operations 242 * 243 * protects: updates to fs_devices counters like missing devices, rw devices, 244 * seeding, structure cloning, opening/closing devices at mount/umount time 245 * 246 * global::fs_devs - add, remove, updates to the global list 247 * 248 * does not protect: manipulation of the fs_devices::devices list! 249 * 250 * btrfs_device::name - renames (write side), read is RCU 251 * 252 * fs_devices::device_list_mutex (per-fs, with RCU) 253 * ------------------------------------------------ 254 * protects updates to fs_devices::devices, ie. adding and deleting 255 * 256 * simple list traversal with read-only actions can be done with RCU protection 257 * 258 * may be used to exclude some operations from running concurrently without any 259 * modifications to the list (see write_all_supers) 260 * 261 * balance_mutex 262 * ------------- 263 * protects balance structures (status, state) and context accessed from 264 * several places (internally, ioctl) 265 * 266 * chunk_mutex 267 * ----------- 268 * protects chunks, adding or removing during allocation, trim or when a new 269 * device is added/removed. Additionally it also protects post_commit_list of 270 * individual devices, since they can be added to the transaction's 271 * post_commit_list only with chunk_mutex held. 272 * 273 * cleaner_mutex 274 * ------------- 275 * a big lock that is held by the cleaner thread and prevents running subvolume 276 * cleaning together with relocation or delayed iputs 277 * 278 * 279 * Lock nesting 280 * ============ 281 * 282 * uuid_mutex 283 * device_list_mutex 284 * chunk_mutex 285 * balance_mutex 286 * 287 * 288 * Exclusive operations, BTRFS_FS_EXCL_OP 289 * ====================================== 290 * 291 * Maintains the exclusivity of the following operations that apply to the 292 * whole filesystem and cannot run in parallel. 293 * 294 * - Balance (*) 295 * - Device add 296 * - Device remove 297 * - Device replace (*) 298 * - Resize 299 * 300 * The device operations (as above) can be in one of the following states: 301 * 302 * - Running state 303 * - Paused state 304 * - Completed state 305 * 306 * Only device operations marked with (*) can go into the Paused state for the 307 * following reasons: 308 * 309 * - ioctl (only Balance can be Paused through ioctl) 310 * - filesystem remounted as read-only 311 * - filesystem unmounted and mounted as read-only 312 * - system power-cycle and filesystem mounted as read-only 313 * - filesystem or device errors leading to forced read-only 314 * 315 * BTRFS_FS_EXCL_OP flag is set and cleared using atomic operations. 316 * During the course of Paused state, the BTRFS_FS_EXCL_OP remains set. 317 * A device operation in Paused or Running state can be canceled or resumed 318 * either by ioctl (Balance only) or when remounted as read-write. 319 * BTRFS_FS_EXCL_OP flag is cleared when the device operation is canceled or 320 * completed. 321 */ 322 323 DEFINE_MUTEX(uuid_mutex); 324 static LIST_HEAD(fs_uuids); 325 struct list_head * __attribute_const__ btrfs_get_fs_uuids(void) 326 { 327 return &fs_uuids; 328 } 329 330 /* 331 * alloc_fs_devices - allocate struct btrfs_fs_devices 332 * @fsid: if not NULL, copy the UUID to fs_devices::fsid 333 * @metadata_fsid: if not NULL, copy the UUID to fs_devices::metadata_fsid 334 * 335 * Return a pointer to a new struct btrfs_fs_devices on success, or ERR_PTR(). 336 * The returned struct is not linked onto any lists and can be destroyed with 337 * kfree() right away. 338 */ 339 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid, 340 const u8 *metadata_fsid) 341 { 342 struct btrfs_fs_devices *fs_devs; 343 344 fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL); 345 if (!fs_devs) 346 return ERR_PTR(-ENOMEM); 347 348 mutex_init(&fs_devs->device_list_mutex); 349 350 INIT_LIST_HEAD(&fs_devs->devices); 351 INIT_LIST_HEAD(&fs_devs->alloc_list); 352 INIT_LIST_HEAD(&fs_devs->fs_list); 353 if (fsid) 354 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE); 355 356 if (metadata_fsid) 357 memcpy(fs_devs->metadata_uuid, metadata_fsid, BTRFS_FSID_SIZE); 358 else if (fsid) 359 memcpy(fs_devs->metadata_uuid, fsid, BTRFS_FSID_SIZE); 360 361 return fs_devs; 362 } 363 364 void btrfs_free_device(struct btrfs_device *device) 365 { 366 WARN_ON(!list_empty(&device->post_commit_list)); 367 rcu_string_free(device->name); 368 extent_io_tree_release(&device->alloc_state); 369 bio_put(device->flush_bio); 370 kfree(device); 371 } 372 373 static void free_fs_devices(struct btrfs_fs_devices *fs_devices) 374 { 375 struct btrfs_device *device; 376 WARN_ON(fs_devices->opened); 377 while (!list_empty(&fs_devices->devices)) { 378 device = list_entry(fs_devices->devices.next, 379 struct btrfs_device, dev_list); 380 list_del(&device->dev_list); 381 btrfs_free_device(device); 382 } 383 kfree(fs_devices); 384 } 385 386 void __exit btrfs_cleanup_fs_uuids(void) 387 { 388 struct btrfs_fs_devices *fs_devices; 389 390 while (!list_empty(&fs_uuids)) { 391 fs_devices = list_entry(fs_uuids.next, 392 struct btrfs_fs_devices, fs_list); 393 list_del(&fs_devices->fs_list); 394 free_fs_devices(fs_devices); 395 } 396 } 397 398 /* 399 * Returns a pointer to a new btrfs_device on success; ERR_PTR() on error. 400 * Returned struct is not linked onto any lists and must be destroyed using 401 * btrfs_free_device. 402 */ 403 static struct btrfs_device *__alloc_device(void) 404 { 405 struct btrfs_device *dev; 406 407 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 408 if (!dev) 409 return ERR_PTR(-ENOMEM); 410 411 /* 412 * Preallocate a bio that's always going to be used for flushing device 413 * barriers and matches the device lifespan 414 */ 415 dev->flush_bio = bio_alloc_bioset(GFP_KERNEL, 0, NULL); 416 if (!dev->flush_bio) { 417 kfree(dev); 418 return ERR_PTR(-ENOMEM); 419 } 420 421 INIT_LIST_HEAD(&dev->dev_list); 422 INIT_LIST_HEAD(&dev->dev_alloc_list); 423 INIT_LIST_HEAD(&dev->post_commit_list); 424 425 atomic_set(&dev->reada_in_flight, 0); 426 atomic_set(&dev->dev_stats_ccnt, 0); 427 btrfs_device_data_ordered_init(dev); 428 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_DIRECT_RECLAIM); 429 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_DIRECT_RECLAIM); 430 extent_io_tree_init(NULL, &dev->alloc_state, 0, NULL); 431 432 return dev; 433 } 434 435 static noinline struct btrfs_fs_devices *find_fsid( 436 const u8 *fsid, const u8 *metadata_fsid) 437 { 438 struct btrfs_fs_devices *fs_devices; 439 440 ASSERT(fsid); 441 442 /* Handle non-split brain cases */ 443 list_for_each_entry(fs_devices, &fs_uuids, fs_list) { 444 if (metadata_fsid) { 445 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0 446 && memcmp(metadata_fsid, fs_devices->metadata_uuid, 447 BTRFS_FSID_SIZE) == 0) 448 return fs_devices; 449 } else { 450 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) 451 return fs_devices; 452 } 453 } 454 return NULL; 455 } 456 457 static struct btrfs_fs_devices *find_fsid_with_metadata_uuid( 458 struct btrfs_super_block *disk_super) 459 { 460 461 struct btrfs_fs_devices *fs_devices; 462 463 /* 464 * Handle scanned device having completed its fsid change but 465 * belonging to a fs_devices that was created by first scanning 466 * a device which didn't have its fsid/metadata_uuid changed 467 * at all and the CHANGING_FSID_V2 flag set. 468 */ 469 list_for_each_entry(fs_devices, &fs_uuids, fs_list) { 470 if (fs_devices->fsid_change && 471 memcmp(disk_super->metadata_uuid, fs_devices->fsid, 472 BTRFS_FSID_SIZE) == 0 && 473 memcmp(fs_devices->fsid, fs_devices->metadata_uuid, 474 BTRFS_FSID_SIZE) == 0) { 475 return fs_devices; 476 } 477 } 478 /* 479 * Handle scanned device having completed its fsid change but 480 * belonging to a fs_devices that was created by a device that 481 * has an outdated pair of fsid/metadata_uuid and 482 * CHANGING_FSID_V2 flag set. 483 */ 484 list_for_each_entry(fs_devices, &fs_uuids, fs_list) { 485 if (fs_devices->fsid_change && 486 memcmp(fs_devices->metadata_uuid, 487 fs_devices->fsid, BTRFS_FSID_SIZE) != 0 && 488 memcmp(disk_super->metadata_uuid, fs_devices->metadata_uuid, 489 BTRFS_FSID_SIZE) == 0) { 490 return fs_devices; 491 } 492 } 493 494 return find_fsid(disk_super->fsid, disk_super->metadata_uuid); 495 } 496 497 498 static int 499 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder, 500 int flush, struct block_device **bdev, 501 struct btrfs_super_block **disk_super) 502 { 503 int ret; 504 505 *bdev = blkdev_get_by_path(device_path, flags, holder); 506 507 if (IS_ERR(*bdev)) { 508 ret = PTR_ERR(*bdev); 509 goto error; 510 } 511 512 if (flush) 513 filemap_write_and_wait((*bdev)->bd_inode->i_mapping); 514 ret = set_blocksize(*bdev, BTRFS_BDEV_BLOCKSIZE); 515 if (ret) { 516 blkdev_put(*bdev, flags); 517 goto error; 518 } 519 invalidate_bdev(*bdev); 520 *disk_super = btrfs_read_dev_super(*bdev); 521 if (IS_ERR(*disk_super)) { 522 ret = PTR_ERR(*disk_super); 523 blkdev_put(*bdev, flags); 524 goto error; 525 } 526 527 return 0; 528 529 error: 530 *bdev = NULL; 531 return ret; 532 } 533 534 static bool device_path_matched(const char *path, struct btrfs_device *device) 535 { 536 int found; 537 538 rcu_read_lock(); 539 found = strcmp(rcu_str_deref(device->name), path); 540 rcu_read_unlock(); 541 542 return found == 0; 543 } 544 545 /* 546 * Search and remove all stale (devices which are not mounted) devices. 547 * When both inputs are NULL, it will search and release all stale devices. 548 * path: Optional. When provided will it release all unmounted devices 549 * matching this path only. 550 * skip_dev: Optional. Will skip this device when searching for the stale 551 * devices. 552 * Return: 0 for success or if @path is NULL. 553 * -EBUSY if @path is a mounted device. 554 * -ENOENT if @path does not match any device in the list. 555 */ 556 static int btrfs_free_stale_devices(const char *path, 557 struct btrfs_device *skip_device) 558 { 559 struct btrfs_fs_devices *fs_devices, *tmp_fs_devices; 560 struct btrfs_device *device, *tmp_device; 561 int ret = 0; 562 563 if (path) 564 ret = -ENOENT; 565 566 list_for_each_entry_safe(fs_devices, tmp_fs_devices, &fs_uuids, fs_list) { 567 568 mutex_lock(&fs_devices->device_list_mutex); 569 list_for_each_entry_safe(device, tmp_device, 570 &fs_devices->devices, dev_list) { 571 if (skip_device && skip_device == device) 572 continue; 573 if (path && !device->name) 574 continue; 575 if (path && !device_path_matched(path, device)) 576 continue; 577 if (fs_devices->opened) { 578 /* for an already deleted device return 0 */ 579 if (path && ret != 0) 580 ret = -EBUSY; 581 break; 582 } 583 584 /* delete the stale device */ 585 fs_devices->num_devices--; 586 list_del(&device->dev_list); 587 btrfs_free_device(device); 588 589 ret = 0; 590 if (fs_devices->num_devices == 0) 591 break; 592 } 593 mutex_unlock(&fs_devices->device_list_mutex); 594 595 if (fs_devices->num_devices == 0) { 596 btrfs_sysfs_remove_fsid(fs_devices); 597 list_del(&fs_devices->fs_list); 598 free_fs_devices(fs_devices); 599 } 600 } 601 602 return ret; 603 } 604 605 static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices, 606 struct btrfs_device *device, fmode_t flags, 607 void *holder) 608 { 609 struct request_queue *q; 610 struct block_device *bdev; 611 struct btrfs_super_block *disk_super; 612 u64 devid; 613 int ret; 614 615 if (device->bdev) 616 return -EINVAL; 617 if (!device->name) 618 return -EINVAL; 619 620 ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, 621 &bdev, &disk_super); 622 if (ret) 623 return ret; 624 625 devid = btrfs_stack_device_id(&disk_super->dev_item); 626 if (devid != device->devid) 627 goto error_free_page; 628 629 if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE)) 630 goto error_free_page; 631 632 device->generation = btrfs_super_generation(disk_super); 633 634 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { 635 if (btrfs_super_incompat_flags(disk_super) & 636 BTRFS_FEATURE_INCOMPAT_METADATA_UUID) { 637 pr_err( 638 "BTRFS: Invalid seeding and uuid-changed device detected\n"); 639 goto error_free_page; 640 } 641 642 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 643 fs_devices->seeding = true; 644 } else { 645 if (bdev_read_only(bdev)) 646 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 647 else 648 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 649 } 650 651 q = bdev_get_queue(bdev); 652 if (!blk_queue_nonrot(q)) 653 fs_devices->rotating = true; 654 655 device->bdev = bdev; 656 clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 657 device->mode = flags; 658 659 fs_devices->open_devices++; 660 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && 661 device->devid != BTRFS_DEV_REPLACE_DEVID) { 662 fs_devices->rw_devices++; 663 list_add_tail(&device->dev_alloc_list, &fs_devices->alloc_list); 664 } 665 btrfs_release_disk_super(disk_super); 666 667 return 0; 668 669 error_free_page: 670 btrfs_release_disk_super(disk_super); 671 blkdev_put(bdev, flags); 672 673 return -EINVAL; 674 } 675 676 /* 677 * Handle scanned device having its CHANGING_FSID_V2 flag set and the fs_devices 678 * being created with a disk that has already completed its fsid change. Such 679 * disk can belong to an fs which has its FSID changed or to one which doesn't. 680 * Handle both cases here. 681 */ 682 static struct btrfs_fs_devices *find_fsid_inprogress( 683 struct btrfs_super_block *disk_super) 684 { 685 struct btrfs_fs_devices *fs_devices; 686 687 list_for_each_entry(fs_devices, &fs_uuids, fs_list) { 688 if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid, 689 BTRFS_FSID_SIZE) != 0 && 690 memcmp(fs_devices->metadata_uuid, disk_super->fsid, 691 BTRFS_FSID_SIZE) == 0 && !fs_devices->fsid_change) { 692 return fs_devices; 693 } 694 } 695 696 return find_fsid(disk_super->fsid, NULL); 697 } 698 699 700 static struct btrfs_fs_devices *find_fsid_changed( 701 struct btrfs_super_block *disk_super) 702 { 703 struct btrfs_fs_devices *fs_devices; 704 705 /* 706 * Handles the case where scanned device is part of an fs that had 707 * multiple successful changes of FSID but curently device didn't 708 * observe it. Meaning our fsid will be different than theirs. We need 709 * to handle two subcases : 710 * 1 - The fs still continues to have different METADATA/FSID uuids. 711 * 2 - The fs is switched back to its original FSID (METADATA/FSID 712 * are equal). 713 */ 714 list_for_each_entry(fs_devices, &fs_uuids, fs_list) { 715 /* Changed UUIDs */ 716 if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid, 717 BTRFS_FSID_SIZE) != 0 && 718 memcmp(fs_devices->metadata_uuid, disk_super->metadata_uuid, 719 BTRFS_FSID_SIZE) == 0 && 720 memcmp(fs_devices->fsid, disk_super->fsid, 721 BTRFS_FSID_SIZE) != 0) 722 return fs_devices; 723 724 /* Unchanged UUIDs */ 725 if (memcmp(fs_devices->metadata_uuid, fs_devices->fsid, 726 BTRFS_FSID_SIZE) == 0 && 727 memcmp(fs_devices->fsid, disk_super->metadata_uuid, 728 BTRFS_FSID_SIZE) == 0) 729 return fs_devices; 730 } 731 732 return NULL; 733 } 734 735 static struct btrfs_fs_devices *find_fsid_reverted_metadata( 736 struct btrfs_super_block *disk_super) 737 { 738 struct btrfs_fs_devices *fs_devices; 739 740 /* 741 * Handle the case where the scanned device is part of an fs whose last 742 * metadata UUID change reverted it to the original FSID. At the same 743 * time * fs_devices was first created by another constitutent device 744 * which didn't fully observe the operation. This results in an 745 * btrfs_fs_devices created with metadata/fsid different AND 746 * btrfs_fs_devices::fsid_change set AND the metadata_uuid of the 747 * fs_devices equal to the FSID of the disk. 748 */ 749 list_for_each_entry(fs_devices, &fs_uuids, fs_list) { 750 if (memcmp(fs_devices->fsid, fs_devices->metadata_uuid, 751 BTRFS_FSID_SIZE) != 0 && 752 memcmp(fs_devices->metadata_uuid, disk_super->fsid, 753 BTRFS_FSID_SIZE) == 0 && 754 fs_devices->fsid_change) 755 return fs_devices; 756 } 757 758 return NULL; 759 } 760 /* 761 * Add new device to list of registered devices 762 * 763 * Returns: 764 * device pointer which was just added or updated when successful 765 * error pointer when failed 766 */ 767 static noinline struct btrfs_device *device_list_add(const char *path, 768 struct btrfs_super_block *disk_super, 769 bool *new_device_added) 770 { 771 struct btrfs_device *device; 772 struct btrfs_fs_devices *fs_devices = NULL; 773 struct rcu_string *name; 774 u64 found_transid = btrfs_super_generation(disk_super); 775 u64 devid = btrfs_stack_device_id(&disk_super->dev_item); 776 bool has_metadata_uuid = (btrfs_super_incompat_flags(disk_super) & 777 BTRFS_FEATURE_INCOMPAT_METADATA_UUID); 778 bool fsid_change_in_progress = (btrfs_super_flags(disk_super) & 779 BTRFS_SUPER_FLAG_CHANGING_FSID_V2); 780 781 if (fsid_change_in_progress) { 782 if (!has_metadata_uuid) 783 fs_devices = find_fsid_inprogress(disk_super); 784 else 785 fs_devices = find_fsid_changed(disk_super); 786 } else if (has_metadata_uuid) { 787 fs_devices = find_fsid_with_metadata_uuid(disk_super); 788 } else { 789 fs_devices = find_fsid_reverted_metadata(disk_super); 790 if (!fs_devices) 791 fs_devices = find_fsid(disk_super->fsid, NULL); 792 } 793 794 795 if (!fs_devices) { 796 if (has_metadata_uuid) 797 fs_devices = alloc_fs_devices(disk_super->fsid, 798 disk_super->metadata_uuid); 799 else 800 fs_devices = alloc_fs_devices(disk_super->fsid, NULL); 801 802 if (IS_ERR(fs_devices)) 803 return ERR_CAST(fs_devices); 804 805 fs_devices->fsid_change = fsid_change_in_progress; 806 807 mutex_lock(&fs_devices->device_list_mutex); 808 list_add(&fs_devices->fs_list, &fs_uuids); 809 810 device = NULL; 811 } else { 812 mutex_lock(&fs_devices->device_list_mutex); 813 device = btrfs_find_device(fs_devices, devid, 814 disk_super->dev_item.uuid, NULL, false); 815 816 /* 817 * If this disk has been pulled into an fs devices created by 818 * a device which had the CHANGING_FSID_V2 flag then replace the 819 * metadata_uuid/fsid values of the fs_devices. 820 */ 821 if (fs_devices->fsid_change && 822 found_transid > fs_devices->latest_generation) { 823 memcpy(fs_devices->fsid, disk_super->fsid, 824 BTRFS_FSID_SIZE); 825 826 if (has_metadata_uuid) 827 memcpy(fs_devices->metadata_uuid, 828 disk_super->metadata_uuid, 829 BTRFS_FSID_SIZE); 830 else 831 memcpy(fs_devices->metadata_uuid, 832 disk_super->fsid, BTRFS_FSID_SIZE); 833 834 fs_devices->fsid_change = false; 835 } 836 } 837 838 if (!device) { 839 if (fs_devices->opened) { 840 mutex_unlock(&fs_devices->device_list_mutex); 841 return ERR_PTR(-EBUSY); 842 } 843 844 device = btrfs_alloc_device(NULL, &devid, 845 disk_super->dev_item.uuid); 846 if (IS_ERR(device)) { 847 mutex_unlock(&fs_devices->device_list_mutex); 848 /* we can safely leave the fs_devices entry around */ 849 return device; 850 } 851 852 name = rcu_string_strdup(path, GFP_NOFS); 853 if (!name) { 854 btrfs_free_device(device); 855 mutex_unlock(&fs_devices->device_list_mutex); 856 return ERR_PTR(-ENOMEM); 857 } 858 rcu_assign_pointer(device->name, name); 859 860 list_add_rcu(&device->dev_list, &fs_devices->devices); 861 fs_devices->num_devices++; 862 863 device->fs_devices = fs_devices; 864 *new_device_added = true; 865 866 if (disk_super->label[0]) 867 pr_info( 868 "BTRFS: device label %s devid %llu transid %llu %s scanned by %s (%d)\n", 869 disk_super->label, devid, found_transid, path, 870 current->comm, task_pid_nr(current)); 871 else 872 pr_info( 873 "BTRFS: device fsid %pU devid %llu transid %llu %s scanned by %s (%d)\n", 874 disk_super->fsid, devid, found_transid, path, 875 current->comm, task_pid_nr(current)); 876 877 } else if (!device->name || strcmp(device->name->str, path)) { 878 /* 879 * When FS is already mounted. 880 * 1. If you are here and if the device->name is NULL that 881 * means this device was missing at time of FS mount. 882 * 2. If you are here and if the device->name is different 883 * from 'path' that means either 884 * a. The same device disappeared and reappeared with 885 * different name. or 886 * b. The missing-disk-which-was-replaced, has 887 * reappeared now. 888 * 889 * We must allow 1 and 2a above. But 2b would be a spurious 890 * and unintentional. 891 * 892 * Further in case of 1 and 2a above, the disk at 'path' 893 * would have missed some transaction when it was away and 894 * in case of 2a the stale bdev has to be updated as well. 895 * 2b must not be allowed at all time. 896 */ 897 898 /* 899 * For now, we do allow update to btrfs_fs_device through the 900 * btrfs dev scan cli after FS has been mounted. We're still 901 * tracking a problem where systems fail mount by subvolume id 902 * when we reject replacement on a mounted FS. 903 */ 904 if (!fs_devices->opened && found_transid < device->generation) { 905 /* 906 * That is if the FS is _not_ mounted and if you 907 * are here, that means there is more than one 908 * disk with same uuid and devid.We keep the one 909 * with larger generation number or the last-in if 910 * generation are equal. 911 */ 912 mutex_unlock(&fs_devices->device_list_mutex); 913 return ERR_PTR(-EEXIST); 914 } 915 916 /* 917 * We are going to replace the device path for a given devid, 918 * make sure it's the same device if the device is mounted 919 */ 920 if (device->bdev) { 921 struct block_device *path_bdev; 922 923 path_bdev = lookup_bdev(path); 924 if (IS_ERR(path_bdev)) { 925 mutex_unlock(&fs_devices->device_list_mutex); 926 return ERR_CAST(path_bdev); 927 } 928 929 if (device->bdev != path_bdev) { 930 bdput(path_bdev); 931 mutex_unlock(&fs_devices->device_list_mutex); 932 btrfs_warn_in_rcu(device->fs_info, 933 "duplicate device fsid:devid for %pU:%llu old:%s new:%s", 934 disk_super->fsid, devid, 935 rcu_str_deref(device->name), path); 936 return ERR_PTR(-EEXIST); 937 } 938 bdput(path_bdev); 939 btrfs_info_in_rcu(device->fs_info, 940 "device fsid %pU devid %llu moved old:%s new:%s", 941 disk_super->fsid, devid, 942 rcu_str_deref(device->name), path); 943 } 944 945 name = rcu_string_strdup(path, GFP_NOFS); 946 if (!name) { 947 mutex_unlock(&fs_devices->device_list_mutex); 948 return ERR_PTR(-ENOMEM); 949 } 950 rcu_string_free(device->name); 951 rcu_assign_pointer(device->name, name); 952 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) { 953 fs_devices->missing_devices--; 954 clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); 955 } 956 } 957 958 /* 959 * Unmount does not free the btrfs_device struct but would zero 960 * generation along with most of the other members. So just update 961 * it back. We need it to pick the disk with largest generation 962 * (as above). 963 */ 964 if (!fs_devices->opened) { 965 device->generation = found_transid; 966 fs_devices->latest_generation = max_t(u64, found_transid, 967 fs_devices->latest_generation); 968 } 969 970 fs_devices->total_devices = btrfs_super_num_devices(disk_super); 971 972 mutex_unlock(&fs_devices->device_list_mutex); 973 return device; 974 } 975 976 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) 977 { 978 struct btrfs_fs_devices *fs_devices; 979 struct btrfs_device *device; 980 struct btrfs_device *orig_dev; 981 int ret = 0; 982 983 fs_devices = alloc_fs_devices(orig->fsid, NULL); 984 if (IS_ERR(fs_devices)) 985 return fs_devices; 986 987 mutex_lock(&orig->device_list_mutex); 988 fs_devices->total_devices = orig->total_devices; 989 990 list_for_each_entry(orig_dev, &orig->devices, dev_list) { 991 struct rcu_string *name; 992 993 device = btrfs_alloc_device(NULL, &orig_dev->devid, 994 orig_dev->uuid); 995 if (IS_ERR(device)) { 996 ret = PTR_ERR(device); 997 goto error; 998 } 999 1000 /* 1001 * This is ok to do without rcu read locked because we hold the 1002 * uuid mutex so nothing we touch in here is going to disappear. 1003 */ 1004 if (orig_dev->name) { 1005 name = rcu_string_strdup(orig_dev->name->str, 1006 GFP_KERNEL); 1007 if (!name) { 1008 btrfs_free_device(device); 1009 ret = -ENOMEM; 1010 goto error; 1011 } 1012 rcu_assign_pointer(device->name, name); 1013 } 1014 1015 list_add(&device->dev_list, &fs_devices->devices); 1016 device->fs_devices = fs_devices; 1017 fs_devices->num_devices++; 1018 } 1019 mutex_unlock(&orig->device_list_mutex); 1020 return fs_devices; 1021 error: 1022 mutex_unlock(&orig->device_list_mutex); 1023 free_fs_devices(fs_devices); 1024 return ERR_PTR(ret); 1025 } 1026 1027 /* 1028 * After we have read the system tree and know devids belonging to 1029 * this filesystem, remove the device which does not belong there. 1030 */ 1031 void btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices, int step) 1032 { 1033 struct btrfs_device *device, *next; 1034 struct btrfs_device *latest_dev = NULL; 1035 1036 mutex_lock(&uuid_mutex); 1037 again: 1038 /* This is the initialized path, it is safe to release the devices. */ 1039 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 1040 if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, 1041 &device->dev_state)) { 1042 if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, 1043 &device->dev_state) && 1044 !test_bit(BTRFS_DEV_STATE_MISSING, 1045 &device->dev_state) && 1046 (!latest_dev || 1047 device->generation > latest_dev->generation)) { 1048 latest_dev = device; 1049 } 1050 continue; 1051 } 1052 1053 if (device->devid == BTRFS_DEV_REPLACE_DEVID) { 1054 /* 1055 * In the first step, keep the device which has 1056 * the correct fsid and the devid that is used 1057 * for the dev_replace procedure. 1058 * In the second step, the dev_replace state is 1059 * read from the device tree and it is known 1060 * whether the procedure is really active or 1061 * not, which means whether this device is 1062 * used or whether it should be removed. 1063 */ 1064 if (step == 0 || test_bit(BTRFS_DEV_STATE_REPLACE_TGT, 1065 &device->dev_state)) { 1066 continue; 1067 } 1068 } 1069 if (device->bdev) { 1070 blkdev_put(device->bdev, device->mode); 1071 device->bdev = NULL; 1072 fs_devices->open_devices--; 1073 } 1074 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { 1075 list_del_init(&device->dev_alloc_list); 1076 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 1077 if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, 1078 &device->dev_state)) 1079 fs_devices->rw_devices--; 1080 } 1081 list_del_init(&device->dev_list); 1082 fs_devices->num_devices--; 1083 btrfs_free_device(device); 1084 } 1085 1086 if (fs_devices->seed) { 1087 fs_devices = fs_devices->seed; 1088 goto again; 1089 } 1090 1091 fs_devices->latest_bdev = latest_dev->bdev; 1092 1093 mutex_unlock(&uuid_mutex); 1094 } 1095 1096 static void btrfs_close_bdev(struct btrfs_device *device) 1097 { 1098 if (!device->bdev) 1099 return; 1100 1101 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { 1102 sync_blockdev(device->bdev); 1103 invalidate_bdev(device->bdev); 1104 } 1105 1106 blkdev_put(device->bdev, device->mode); 1107 } 1108 1109 static void btrfs_close_one_device(struct btrfs_device *device) 1110 { 1111 struct btrfs_fs_devices *fs_devices = device->fs_devices; 1112 1113 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && 1114 device->devid != BTRFS_DEV_REPLACE_DEVID) { 1115 list_del_init(&device->dev_alloc_list); 1116 fs_devices->rw_devices--; 1117 } 1118 1119 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) 1120 fs_devices->missing_devices--; 1121 1122 btrfs_close_bdev(device); 1123 if (device->bdev) { 1124 fs_devices->open_devices--; 1125 device->bdev = NULL; 1126 } 1127 clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 1128 1129 device->fs_info = NULL; 1130 atomic_set(&device->dev_stats_ccnt, 0); 1131 extent_io_tree_release(&device->alloc_state); 1132 1133 /* Verify the device is back in a pristine state */ 1134 ASSERT(!test_bit(BTRFS_DEV_STATE_FLUSH_SENT, &device->dev_state)); 1135 ASSERT(!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)); 1136 ASSERT(list_empty(&device->dev_alloc_list)); 1137 ASSERT(list_empty(&device->post_commit_list)); 1138 ASSERT(atomic_read(&device->reada_in_flight) == 0); 1139 } 1140 1141 static int close_fs_devices(struct btrfs_fs_devices *fs_devices) 1142 { 1143 struct btrfs_device *device, *tmp; 1144 1145 if (--fs_devices->opened > 0) 1146 return 0; 1147 1148 mutex_lock(&fs_devices->device_list_mutex); 1149 list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list) { 1150 btrfs_close_one_device(device); 1151 } 1152 mutex_unlock(&fs_devices->device_list_mutex); 1153 1154 WARN_ON(fs_devices->open_devices); 1155 WARN_ON(fs_devices->rw_devices); 1156 fs_devices->opened = 0; 1157 fs_devices->seeding = false; 1158 1159 return 0; 1160 } 1161 1162 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 1163 { 1164 struct btrfs_fs_devices *seed_devices = NULL; 1165 int ret; 1166 1167 mutex_lock(&uuid_mutex); 1168 ret = close_fs_devices(fs_devices); 1169 if (!fs_devices->opened) { 1170 seed_devices = fs_devices->seed; 1171 fs_devices->seed = NULL; 1172 } 1173 mutex_unlock(&uuid_mutex); 1174 1175 while (seed_devices) { 1176 fs_devices = seed_devices; 1177 seed_devices = fs_devices->seed; 1178 close_fs_devices(fs_devices); 1179 free_fs_devices(fs_devices); 1180 } 1181 return ret; 1182 } 1183 1184 static int open_fs_devices(struct btrfs_fs_devices *fs_devices, 1185 fmode_t flags, void *holder) 1186 { 1187 struct btrfs_device *device; 1188 struct btrfs_device *latest_dev = NULL; 1189 1190 flags |= FMODE_EXCL; 1191 1192 list_for_each_entry(device, &fs_devices->devices, dev_list) { 1193 /* Just open everything we can; ignore failures here */ 1194 if (btrfs_open_one_device(fs_devices, device, flags, holder)) 1195 continue; 1196 1197 if (!latest_dev || 1198 device->generation > latest_dev->generation) 1199 latest_dev = device; 1200 } 1201 if (fs_devices->open_devices == 0) 1202 return -EINVAL; 1203 1204 fs_devices->opened = 1; 1205 fs_devices->latest_bdev = latest_dev->bdev; 1206 fs_devices->total_rw_bytes = 0; 1207 fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_REGULAR; 1208 1209 return 0; 1210 } 1211 1212 static int devid_cmp(void *priv, struct list_head *a, struct list_head *b) 1213 { 1214 struct btrfs_device *dev1, *dev2; 1215 1216 dev1 = list_entry(a, struct btrfs_device, dev_list); 1217 dev2 = list_entry(b, struct btrfs_device, dev_list); 1218 1219 if (dev1->devid < dev2->devid) 1220 return -1; 1221 else if (dev1->devid > dev2->devid) 1222 return 1; 1223 return 0; 1224 } 1225 1226 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 1227 fmode_t flags, void *holder) 1228 { 1229 int ret; 1230 1231 lockdep_assert_held(&uuid_mutex); 1232 1233 mutex_lock(&fs_devices->device_list_mutex); 1234 if (fs_devices->opened) { 1235 fs_devices->opened++; 1236 ret = 0; 1237 } else { 1238 list_sort(NULL, &fs_devices->devices, devid_cmp); 1239 ret = open_fs_devices(fs_devices, flags, holder); 1240 } 1241 mutex_unlock(&fs_devices->device_list_mutex); 1242 1243 return ret; 1244 } 1245 1246 void btrfs_release_disk_super(struct btrfs_super_block *super) 1247 { 1248 struct page *page = virt_to_page(super); 1249 1250 put_page(page); 1251 } 1252 1253 static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev, 1254 u64 bytenr) 1255 { 1256 struct btrfs_super_block *disk_super; 1257 struct page *page; 1258 void *p; 1259 pgoff_t index; 1260 1261 /* make sure our super fits in the device */ 1262 if (bytenr + PAGE_SIZE >= i_size_read(bdev->bd_inode)) 1263 return ERR_PTR(-EINVAL); 1264 1265 /* make sure our super fits in the page */ 1266 if (sizeof(*disk_super) > PAGE_SIZE) 1267 return ERR_PTR(-EINVAL); 1268 1269 /* make sure our super doesn't straddle pages on disk */ 1270 index = bytenr >> PAGE_SHIFT; 1271 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index) 1272 return ERR_PTR(-EINVAL); 1273 1274 /* pull in the page with our super */ 1275 page = read_cache_page_gfp(bdev->bd_inode->i_mapping, index, GFP_KERNEL); 1276 1277 if (IS_ERR(page)) 1278 return ERR_CAST(page); 1279 1280 p = page_address(page); 1281 1282 /* align our pointer to the offset of the super block */ 1283 disk_super = p + offset_in_page(bytenr); 1284 1285 if (btrfs_super_bytenr(disk_super) != bytenr || 1286 btrfs_super_magic(disk_super) != BTRFS_MAGIC) { 1287 btrfs_release_disk_super(p); 1288 return ERR_PTR(-EINVAL); 1289 } 1290 1291 if (disk_super->label[0] && disk_super->label[BTRFS_LABEL_SIZE - 1]) 1292 disk_super->label[BTRFS_LABEL_SIZE - 1] = 0; 1293 1294 return disk_super; 1295 } 1296 1297 int btrfs_forget_devices(const char *path) 1298 { 1299 int ret; 1300 1301 mutex_lock(&uuid_mutex); 1302 ret = btrfs_free_stale_devices(strlen(path) ? path : NULL, NULL); 1303 mutex_unlock(&uuid_mutex); 1304 1305 return ret; 1306 } 1307 1308 /* 1309 * Look for a btrfs signature on a device. This may be called out of the mount path 1310 * and we are not allowed to call set_blocksize during the scan. The superblock 1311 * is read via pagecache 1312 */ 1313 struct btrfs_device *btrfs_scan_one_device(const char *path, fmode_t flags, 1314 void *holder) 1315 { 1316 struct btrfs_super_block *disk_super; 1317 bool new_device_added = false; 1318 struct btrfs_device *device = NULL; 1319 struct block_device *bdev; 1320 u64 bytenr; 1321 1322 lockdep_assert_held(&uuid_mutex); 1323 1324 /* 1325 * we would like to check all the supers, but that would make 1326 * a btrfs mount succeed after a mkfs from a different FS. 1327 * So, we need to add a special mount option to scan for 1328 * later supers, using BTRFS_SUPER_MIRROR_MAX instead 1329 */ 1330 bytenr = btrfs_sb_offset(0); 1331 flags |= FMODE_EXCL; 1332 1333 bdev = blkdev_get_by_path(path, flags, holder); 1334 if (IS_ERR(bdev)) 1335 return ERR_CAST(bdev); 1336 1337 disk_super = btrfs_read_disk_super(bdev, bytenr); 1338 if (IS_ERR(disk_super)) { 1339 device = ERR_CAST(disk_super); 1340 goto error_bdev_put; 1341 } 1342 1343 device = device_list_add(path, disk_super, &new_device_added); 1344 if (!IS_ERR(device)) { 1345 if (new_device_added) 1346 btrfs_free_stale_devices(path, device); 1347 } 1348 1349 btrfs_release_disk_super(disk_super); 1350 1351 error_bdev_put: 1352 blkdev_put(bdev, flags); 1353 1354 return device; 1355 } 1356 1357 /* 1358 * Try to find a chunk that intersects [start, start + len] range and when one 1359 * such is found, record the end of it in *start 1360 */ 1361 static bool contains_pending_extent(struct btrfs_device *device, u64 *start, 1362 u64 len) 1363 { 1364 u64 physical_start, physical_end; 1365 1366 lockdep_assert_held(&device->fs_info->chunk_mutex); 1367 1368 if (!find_first_extent_bit(&device->alloc_state, *start, 1369 &physical_start, &physical_end, 1370 CHUNK_ALLOCATED, NULL)) { 1371 1372 if (in_range(physical_start, *start, len) || 1373 in_range(*start, physical_start, 1374 physical_end - physical_start)) { 1375 *start = physical_end + 1; 1376 return true; 1377 } 1378 } 1379 return false; 1380 } 1381 1382 static u64 dev_extent_search_start(struct btrfs_device *device, u64 start) 1383 { 1384 switch (device->fs_devices->chunk_alloc_policy) { 1385 case BTRFS_CHUNK_ALLOC_REGULAR: 1386 /* 1387 * We don't want to overwrite the superblock on the drive nor 1388 * any area used by the boot loader (grub for example), so we 1389 * make sure to start at an offset of at least 1MB. 1390 */ 1391 return max_t(u64, start, SZ_1M); 1392 default: 1393 BUG(); 1394 } 1395 } 1396 1397 /** 1398 * dev_extent_hole_check - check if specified hole is suitable for allocation 1399 * @device: the device which we have the hole 1400 * @hole_start: starting position of the hole 1401 * @hole_size: the size of the hole 1402 * @num_bytes: the size of the free space that we need 1403 * 1404 * This function may modify @hole_start and @hole_end to reflect the suitable 1405 * position for allocation. Returns 1 if hole position is updated, 0 otherwise. 1406 */ 1407 static bool dev_extent_hole_check(struct btrfs_device *device, u64 *hole_start, 1408 u64 *hole_size, u64 num_bytes) 1409 { 1410 bool changed = false; 1411 u64 hole_end = *hole_start + *hole_size; 1412 1413 /* 1414 * Check before we set max_hole_start, otherwise we could end up 1415 * sending back this offset anyway. 1416 */ 1417 if (contains_pending_extent(device, hole_start, *hole_size)) { 1418 if (hole_end >= *hole_start) 1419 *hole_size = hole_end - *hole_start; 1420 else 1421 *hole_size = 0; 1422 changed = true; 1423 } 1424 1425 switch (device->fs_devices->chunk_alloc_policy) { 1426 case BTRFS_CHUNK_ALLOC_REGULAR: 1427 /* No extra check */ 1428 break; 1429 default: 1430 BUG(); 1431 } 1432 1433 return changed; 1434 } 1435 1436 /* 1437 * find_free_dev_extent_start - find free space in the specified device 1438 * @device: the device which we search the free space in 1439 * @num_bytes: the size of the free space that we need 1440 * @search_start: the position from which to begin the search 1441 * @start: store the start of the free space. 1442 * @len: the size of the free space. that we find, or the size 1443 * of the max free space if we don't find suitable free space 1444 * 1445 * this uses a pretty simple search, the expectation is that it is 1446 * called very infrequently and that a given device has a small number 1447 * of extents 1448 * 1449 * @start is used to store the start of the free space if we find. But if we 1450 * don't find suitable free space, it will be used to store the start position 1451 * of the max free space. 1452 * 1453 * @len is used to store the size of the free space that we find. 1454 * But if we don't find suitable free space, it is used to store the size of 1455 * the max free space. 1456 * 1457 * NOTE: This function will search *commit* root of device tree, and does extra 1458 * check to ensure dev extents are not double allocated. 1459 * This makes the function safe to allocate dev extents but may not report 1460 * correct usable device space, as device extent freed in current transaction 1461 * is not reported as avaiable. 1462 */ 1463 static int find_free_dev_extent_start(struct btrfs_device *device, 1464 u64 num_bytes, u64 search_start, u64 *start, 1465 u64 *len) 1466 { 1467 struct btrfs_fs_info *fs_info = device->fs_info; 1468 struct btrfs_root *root = fs_info->dev_root; 1469 struct btrfs_key key; 1470 struct btrfs_dev_extent *dev_extent; 1471 struct btrfs_path *path; 1472 u64 hole_size; 1473 u64 max_hole_start; 1474 u64 max_hole_size; 1475 u64 extent_end; 1476 u64 search_end = device->total_bytes; 1477 int ret; 1478 int slot; 1479 struct extent_buffer *l; 1480 1481 search_start = dev_extent_search_start(device, search_start); 1482 1483 path = btrfs_alloc_path(); 1484 if (!path) 1485 return -ENOMEM; 1486 1487 max_hole_start = search_start; 1488 max_hole_size = 0; 1489 1490 again: 1491 if (search_start >= search_end || 1492 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { 1493 ret = -ENOSPC; 1494 goto out; 1495 } 1496 1497 path->reada = READA_FORWARD; 1498 path->search_commit_root = 1; 1499 path->skip_locking = 1; 1500 1501 key.objectid = device->devid; 1502 key.offset = search_start; 1503 key.type = BTRFS_DEV_EXTENT_KEY; 1504 1505 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1506 if (ret < 0) 1507 goto out; 1508 if (ret > 0) { 1509 ret = btrfs_previous_item(root, path, key.objectid, key.type); 1510 if (ret < 0) 1511 goto out; 1512 } 1513 1514 while (1) { 1515 l = path->nodes[0]; 1516 slot = path->slots[0]; 1517 if (slot >= btrfs_header_nritems(l)) { 1518 ret = btrfs_next_leaf(root, path); 1519 if (ret == 0) 1520 continue; 1521 if (ret < 0) 1522 goto out; 1523 1524 break; 1525 } 1526 btrfs_item_key_to_cpu(l, &key, slot); 1527 1528 if (key.objectid < device->devid) 1529 goto next; 1530 1531 if (key.objectid > device->devid) 1532 break; 1533 1534 if (key.type != BTRFS_DEV_EXTENT_KEY) 1535 goto next; 1536 1537 if (key.offset > search_start) { 1538 hole_size = key.offset - search_start; 1539 dev_extent_hole_check(device, &search_start, &hole_size, 1540 num_bytes); 1541 1542 if (hole_size > max_hole_size) { 1543 max_hole_start = search_start; 1544 max_hole_size = hole_size; 1545 } 1546 1547 /* 1548 * If this free space is greater than which we need, 1549 * it must be the max free space that we have found 1550 * until now, so max_hole_start must point to the start 1551 * of this free space and the length of this free space 1552 * is stored in max_hole_size. Thus, we return 1553 * max_hole_start and max_hole_size and go back to the 1554 * caller. 1555 */ 1556 if (hole_size >= num_bytes) { 1557 ret = 0; 1558 goto out; 1559 } 1560 } 1561 1562 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 1563 extent_end = key.offset + btrfs_dev_extent_length(l, 1564 dev_extent); 1565 if (extent_end > search_start) 1566 search_start = extent_end; 1567 next: 1568 path->slots[0]++; 1569 cond_resched(); 1570 } 1571 1572 /* 1573 * At this point, search_start should be the end of 1574 * allocated dev extents, and when shrinking the device, 1575 * search_end may be smaller than search_start. 1576 */ 1577 if (search_end > search_start) { 1578 hole_size = search_end - search_start; 1579 if (dev_extent_hole_check(device, &search_start, &hole_size, 1580 num_bytes)) { 1581 btrfs_release_path(path); 1582 goto again; 1583 } 1584 1585 if (hole_size > max_hole_size) { 1586 max_hole_start = search_start; 1587 max_hole_size = hole_size; 1588 } 1589 } 1590 1591 /* See above. */ 1592 if (max_hole_size < num_bytes) 1593 ret = -ENOSPC; 1594 else 1595 ret = 0; 1596 1597 out: 1598 btrfs_free_path(path); 1599 *start = max_hole_start; 1600 if (len) 1601 *len = max_hole_size; 1602 return ret; 1603 } 1604 1605 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes, 1606 u64 *start, u64 *len) 1607 { 1608 /* FIXME use last free of some kind */ 1609 return find_free_dev_extent_start(device, num_bytes, 0, start, len); 1610 } 1611 1612 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, 1613 struct btrfs_device *device, 1614 u64 start, u64 *dev_extent_len) 1615 { 1616 struct btrfs_fs_info *fs_info = device->fs_info; 1617 struct btrfs_root *root = fs_info->dev_root; 1618 int ret; 1619 struct btrfs_path *path; 1620 struct btrfs_key key; 1621 struct btrfs_key found_key; 1622 struct extent_buffer *leaf = NULL; 1623 struct btrfs_dev_extent *extent = NULL; 1624 1625 path = btrfs_alloc_path(); 1626 if (!path) 1627 return -ENOMEM; 1628 1629 key.objectid = device->devid; 1630 key.offset = start; 1631 key.type = BTRFS_DEV_EXTENT_KEY; 1632 again: 1633 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1634 if (ret > 0) { 1635 ret = btrfs_previous_item(root, path, key.objectid, 1636 BTRFS_DEV_EXTENT_KEY); 1637 if (ret) 1638 goto out; 1639 leaf = path->nodes[0]; 1640 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1641 extent = btrfs_item_ptr(leaf, path->slots[0], 1642 struct btrfs_dev_extent); 1643 BUG_ON(found_key.offset > start || found_key.offset + 1644 btrfs_dev_extent_length(leaf, extent) < start); 1645 key = found_key; 1646 btrfs_release_path(path); 1647 goto again; 1648 } else if (ret == 0) { 1649 leaf = path->nodes[0]; 1650 extent = btrfs_item_ptr(leaf, path->slots[0], 1651 struct btrfs_dev_extent); 1652 } else { 1653 btrfs_handle_fs_error(fs_info, ret, "Slot search failed"); 1654 goto out; 1655 } 1656 1657 *dev_extent_len = btrfs_dev_extent_length(leaf, extent); 1658 1659 ret = btrfs_del_item(trans, root, path); 1660 if (ret) { 1661 btrfs_handle_fs_error(fs_info, ret, 1662 "Failed to remove dev extent item"); 1663 } else { 1664 set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags); 1665 } 1666 out: 1667 btrfs_free_path(path); 1668 return ret; 1669 } 1670 1671 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, 1672 struct btrfs_device *device, 1673 u64 chunk_offset, u64 start, u64 num_bytes) 1674 { 1675 int ret; 1676 struct btrfs_path *path; 1677 struct btrfs_fs_info *fs_info = device->fs_info; 1678 struct btrfs_root *root = fs_info->dev_root; 1679 struct btrfs_dev_extent *extent; 1680 struct extent_buffer *leaf; 1681 struct btrfs_key key; 1682 1683 WARN_ON(!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state)); 1684 WARN_ON(test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)); 1685 path = btrfs_alloc_path(); 1686 if (!path) 1687 return -ENOMEM; 1688 1689 key.objectid = device->devid; 1690 key.offset = start; 1691 key.type = BTRFS_DEV_EXTENT_KEY; 1692 ret = btrfs_insert_empty_item(trans, root, path, &key, 1693 sizeof(*extent)); 1694 if (ret) 1695 goto out; 1696 1697 leaf = path->nodes[0]; 1698 extent = btrfs_item_ptr(leaf, path->slots[0], 1699 struct btrfs_dev_extent); 1700 btrfs_set_dev_extent_chunk_tree(leaf, extent, 1701 BTRFS_CHUNK_TREE_OBJECTID); 1702 btrfs_set_dev_extent_chunk_objectid(leaf, extent, 1703 BTRFS_FIRST_CHUNK_TREE_OBJECTID); 1704 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); 1705 1706 btrfs_set_dev_extent_length(leaf, extent, num_bytes); 1707 btrfs_mark_buffer_dirty(leaf); 1708 out: 1709 btrfs_free_path(path); 1710 return ret; 1711 } 1712 1713 static u64 find_next_chunk(struct btrfs_fs_info *fs_info) 1714 { 1715 struct extent_map_tree *em_tree; 1716 struct extent_map *em; 1717 struct rb_node *n; 1718 u64 ret = 0; 1719 1720 em_tree = &fs_info->mapping_tree; 1721 read_lock(&em_tree->lock); 1722 n = rb_last(&em_tree->map.rb_root); 1723 if (n) { 1724 em = rb_entry(n, struct extent_map, rb_node); 1725 ret = em->start + em->len; 1726 } 1727 read_unlock(&em_tree->lock); 1728 1729 return ret; 1730 } 1731 1732 static noinline int find_next_devid(struct btrfs_fs_info *fs_info, 1733 u64 *devid_ret) 1734 { 1735 int ret; 1736 struct btrfs_key key; 1737 struct btrfs_key found_key; 1738 struct btrfs_path *path; 1739 1740 path = btrfs_alloc_path(); 1741 if (!path) 1742 return -ENOMEM; 1743 1744 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1745 key.type = BTRFS_DEV_ITEM_KEY; 1746 key.offset = (u64)-1; 1747 1748 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0); 1749 if (ret < 0) 1750 goto error; 1751 1752 if (ret == 0) { 1753 /* Corruption */ 1754 btrfs_err(fs_info, "corrupted chunk tree devid -1 matched"); 1755 ret = -EUCLEAN; 1756 goto error; 1757 } 1758 1759 ret = btrfs_previous_item(fs_info->chunk_root, path, 1760 BTRFS_DEV_ITEMS_OBJECTID, 1761 BTRFS_DEV_ITEM_KEY); 1762 if (ret) { 1763 *devid_ret = 1; 1764 } else { 1765 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1766 path->slots[0]); 1767 *devid_ret = found_key.offset + 1; 1768 } 1769 ret = 0; 1770 error: 1771 btrfs_free_path(path); 1772 return ret; 1773 } 1774 1775 /* 1776 * the device information is stored in the chunk root 1777 * the btrfs_device struct should be fully filled in 1778 */ 1779 static int btrfs_add_dev_item(struct btrfs_trans_handle *trans, 1780 struct btrfs_device *device) 1781 { 1782 int ret; 1783 struct btrfs_path *path; 1784 struct btrfs_dev_item *dev_item; 1785 struct extent_buffer *leaf; 1786 struct btrfs_key key; 1787 unsigned long ptr; 1788 1789 path = btrfs_alloc_path(); 1790 if (!path) 1791 return -ENOMEM; 1792 1793 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1794 key.type = BTRFS_DEV_ITEM_KEY; 1795 key.offset = device->devid; 1796 1797 ret = btrfs_insert_empty_item(trans, trans->fs_info->chunk_root, path, 1798 &key, sizeof(*dev_item)); 1799 if (ret) 1800 goto out; 1801 1802 leaf = path->nodes[0]; 1803 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 1804 1805 btrfs_set_device_id(leaf, dev_item, device->devid); 1806 btrfs_set_device_generation(leaf, dev_item, 0); 1807 btrfs_set_device_type(leaf, dev_item, device->type); 1808 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 1809 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 1810 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 1811 btrfs_set_device_total_bytes(leaf, dev_item, 1812 btrfs_device_get_disk_total_bytes(device)); 1813 btrfs_set_device_bytes_used(leaf, dev_item, 1814 btrfs_device_get_bytes_used(device)); 1815 btrfs_set_device_group(leaf, dev_item, 0); 1816 btrfs_set_device_seek_speed(leaf, dev_item, 0); 1817 btrfs_set_device_bandwidth(leaf, dev_item, 0); 1818 btrfs_set_device_start_offset(leaf, dev_item, 0); 1819 1820 ptr = btrfs_device_uuid(dev_item); 1821 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 1822 ptr = btrfs_device_fsid(dev_item); 1823 write_extent_buffer(leaf, trans->fs_info->fs_devices->metadata_uuid, 1824 ptr, BTRFS_FSID_SIZE); 1825 btrfs_mark_buffer_dirty(leaf); 1826 1827 ret = 0; 1828 out: 1829 btrfs_free_path(path); 1830 return ret; 1831 } 1832 1833 /* 1834 * Function to update ctime/mtime for a given device path. 1835 * Mainly used for ctime/mtime based probe like libblkid. 1836 */ 1837 static void update_dev_time(const char *path_name) 1838 { 1839 struct file *filp; 1840 1841 filp = filp_open(path_name, O_RDWR, 0); 1842 if (IS_ERR(filp)) 1843 return; 1844 file_update_time(filp); 1845 filp_close(filp, NULL); 1846 } 1847 1848 static int btrfs_rm_dev_item(struct btrfs_device *device) 1849 { 1850 struct btrfs_root *root = device->fs_info->chunk_root; 1851 int ret; 1852 struct btrfs_path *path; 1853 struct btrfs_key key; 1854 struct btrfs_trans_handle *trans; 1855 1856 path = btrfs_alloc_path(); 1857 if (!path) 1858 return -ENOMEM; 1859 1860 trans = btrfs_start_transaction(root, 0); 1861 if (IS_ERR(trans)) { 1862 btrfs_free_path(path); 1863 return PTR_ERR(trans); 1864 } 1865 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1866 key.type = BTRFS_DEV_ITEM_KEY; 1867 key.offset = device->devid; 1868 1869 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1870 if (ret) { 1871 if (ret > 0) 1872 ret = -ENOENT; 1873 btrfs_abort_transaction(trans, ret); 1874 btrfs_end_transaction(trans); 1875 goto out; 1876 } 1877 1878 ret = btrfs_del_item(trans, root, path); 1879 if (ret) { 1880 btrfs_abort_transaction(trans, ret); 1881 btrfs_end_transaction(trans); 1882 } 1883 1884 out: 1885 btrfs_free_path(path); 1886 if (!ret) 1887 ret = btrfs_commit_transaction(trans); 1888 return ret; 1889 } 1890 1891 /* 1892 * Verify that @num_devices satisfies the RAID profile constraints in the whole 1893 * filesystem. It's up to the caller to adjust that number regarding eg. device 1894 * replace. 1895 */ 1896 static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info, 1897 u64 num_devices) 1898 { 1899 u64 all_avail; 1900 unsigned seq; 1901 int i; 1902 1903 do { 1904 seq = read_seqbegin(&fs_info->profiles_lock); 1905 1906 all_avail = fs_info->avail_data_alloc_bits | 1907 fs_info->avail_system_alloc_bits | 1908 fs_info->avail_metadata_alloc_bits; 1909 } while (read_seqretry(&fs_info->profiles_lock, seq)); 1910 1911 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { 1912 if (!(all_avail & btrfs_raid_array[i].bg_flag)) 1913 continue; 1914 1915 if (num_devices < btrfs_raid_array[i].devs_min) { 1916 int ret = btrfs_raid_array[i].mindev_error; 1917 1918 if (ret) 1919 return ret; 1920 } 1921 } 1922 1923 return 0; 1924 } 1925 1926 static struct btrfs_device * btrfs_find_next_active_device( 1927 struct btrfs_fs_devices *fs_devs, struct btrfs_device *device) 1928 { 1929 struct btrfs_device *next_device; 1930 1931 list_for_each_entry(next_device, &fs_devs->devices, dev_list) { 1932 if (next_device != device && 1933 !test_bit(BTRFS_DEV_STATE_MISSING, &next_device->dev_state) 1934 && next_device->bdev) 1935 return next_device; 1936 } 1937 1938 return NULL; 1939 } 1940 1941 /* 1942 * Helper function to check if the given device is part of s_bdev / latest_bdev 1943 * and replace it with the provided or the next active device, in the context 1944 * where this function called, there should be always be another device (or 1945 * this_dev) which is active. 1946 */ 1947 void __cold btrfs_assign_next_active_device(struct btrfs_device *device, 1948 struct btrfs_device *this_dev) 1949 { 1950 struct btrfs_fs_info *fs_info = device->fs_info; 1951 struct btrfs_device *next_device; 1952 1953 if (this_dev) 1954 next_device = this_dev; 1955 else 1956 next_device = btrfs_find_next_active_device(fs_info->fs_devices, 1957 device); 1958 ASSERT(next_device); 1959 1960 if (fs_info->sb->s_bdev && 1961 (fs_info->sb->s_bdev == device->bdev)) 1962 fs_info->sb->s_bdev = next_device->bdev; 1963 1964 if (fs_info->fs_devices->latest_bdev == device->bdev) 1965 fs_info->fs_devices->latest_bdev = next_device->bdev; 1966 } 1967 1968 /* 1969 * Return btrfs_fs_devices::num_devices excluding the device that's being 1970 * currently replaced. 1971 */ 1972 static u64 btrfs_num_devices(struct btrfs_fs_info *fs_info) 1973 { 1974 u64 num_devices = fs_info->fs_devices->num_devices; 1975 1976 down_read(&fs_info->dev_replace.rwsem); 1977 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { 1978 ASSERT(num_devices > 1); 1979 num_devices--; 1980 } 1981 up_read(&fs_info->dev_replace.rwsem); 1982 1983 return num_devices; 1984 } 1985 1986 static void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info, 1987 struct block_device *bdev, 1988 const char *device_path) 1989 { 1990 struct btrfs_super_block *disk_super; 1991 int copy_num; 1992 1993 if (!bdev) 1994 return; 1995 1996 for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX; copy_num++) { 1997 struct page *page; 1998 int ret; 1999 2000 disk_super = btrfs_read_dev_one_super(bdev, copy_num); 2001 if (IS_ERR(disk_super)) 2002 continue; 2003 2004 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 2005 2006 page = virt_to_page(disk_super); 2007 set_page_dirty(page); 2008 lock_page(page); 2009 /* write_on_page() unlocks the page */ 2010 ret = write_one_page(page); 2011 if (ret) 2012 btrfs_warn(fs_info, 2013 "error clearing superblock number %d (%d)", 2014 copy_num, ret); 2015 btrfs_release_disk_super(disk_super); 2016 2017 } 2018 2019 /* Notify udev that device has changed */ 2020 btrfs_kobject_uevent(bdev, KOBJ_CHANGE); 2021 2022 /* Update ctime/mtime for device path for libblkid */ 2023 update_dev_time(device_path); 2024 } 2025 2026 int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path, 2027 u64 devid) 2028 { 2029 struct btrfs_device *device; 2030 struct btrfs_fs_devices *cur_devices; 2031 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 2032 u64 num_devices; 2033 int ret = 0; 2034 2035 mutex_lock(&uuid_mutex); 2036 2037 num_devices = btrfs_num_devices(fs_info); 2038 2039 ret = btrfs_check_raid_min_devices(fs_info, num_devices - 1); 2040 if (ret) 2041 goto out; 2042 2043 device = btrfs_find_device_by_devspec(fs_info, devid, device_path); 2044 2045 if (IS_ERR(device)) { 2046 if (PTR_ERR(device) == -ENOENT && 2047 strcmp(device_path, "missing") == 0) 2048 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND; 2049 else 2050 ret = PTR_ERR(device); 2051 goto out; 2052 } 2053 2054 if (btrfs_pinned_by_swapfile(fs_info, device)) { 2055 btrfs_warn_in_rcu(fs_info, 2056 "cannot remove device %s (devid %llu) due to active swapfile", 2057 rcu_str_deref(device->name), device->devid); 2058 ret = -ETXTBSY; 2059 goto out; 2060 } 2061 2062 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { 2063 ret = BTRFS_ERROR_DEV_TGT_REPLACE; 2064 goto out; 2065 } 2066 2067 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && 2068 fs_info->fs_devices->rw_devices == 1) { 2069 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE; 2070 goto out; 2071 } 2072 2073 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { 2074 mutex_lock(&fs_info->chunk_mutex); 2075 list_del_init(&device->dev_alloc_list); 2076 device->fs_devices->rw_devices--; 2077 mutex_unlock(&fs_info->chunk_mutex); 2078 } 2079 2080 mutex_unlock(&uuid_mutex); 2081 ret = btrfs_shrink_device(device, 0); 2082 mutex_lock(&uuid_mutex); 2083 if (ret) 2084 goto error_undo; 2085 2086 /* 2087 * TODO: the superblock still includes this device in its num_devices 2088 * counter although write_all_supers() is not locked out. This 2089 * could give a filesystem state which requires a degraded mount. 2090 */ 2091 ret = btrfs_rm_dev_item(device); 2092 if (ret) 2093 goto error_undo; 2094 2095 clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 2096 btrfs_scrub_cancel_dev(device); 2097 2098 /* 2099 * the device list mutex makes sure that we don't change 2100 * the device list while someone else is writing out all 2101 * the device supers. Whoever is writing all supers, should 2102 * lock the device list mutex before getting the number of 2103 * devices in the super block (super_copy). Conversely, 2104 * whoever updates the number of devices in the super block 2105 * (super_copy) should hold the device list mutex. 2106 */ 2107 2108 /* 2109 * In normal cases the cur_devices == fs_devices. But in case 2110 * of deleting a seed device, the cur_devices should point to 2111 * its own fs_devices listed under the fs_devices->seed. 2112 */ 2113 cur_devices = device->fs_devices; 2114 mutex_lock(&fs_devices->device_list_mutex); 2115 list_del_rcu(&device->dev_list); 2116 2117 cur_devices->num_devices--; 2118 cur_devices->total_devices--; 2119 /* Update total_devices of the parent fs_devices if it's seed */ 2120 if (cur_devices != fs_devices) 2121 fs_devices->total_devices--; 2122 2123 if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) 2124 cur_devices->missing_devices--; 2125 2126 btrfs_assign_next_active_device(device, NULL); 2127 2128 if (device->bdev) { 2129 cur_devices->open_devices--; 2130 /* remove sysfs entry */ 2131 btrfs_sysfs_remove_devices_dir(fs_devices, device); 2132 } 2133 2134 num_devices = btrfs_super_num_devices(fs_info->super_copy) - 1; 2135 btrfs_set_super_num_devices(fs_info->super_copy, num_devices); 2136 mutex_unlock(&fs_devices->device_list_mutex); 2137 2138 /* 2139 * at this point, the device is zero sized and detached from 2140 * the devices list. All that's left is to zero out the old 2141 * supers and free the device. 2142 */ 2143 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) 2144 btrfs_scratch_superblocks(fs_info, device->bdev, 2145 device->name->str); 2146 2147 btrfs_close_bdev(device); 2148 synchronize_rcu(); 2149 btrfs_free_device(device); 2150 2151 if (cur_devices->open_devices == 0) { 2152 while (fs_devices) { 2153 if (fs_devices->seed == cur_devices) { 2154 fs_devices->seed = cur_devices->seed; 2155 break; 2156 } 2157 fs_devices = fs_devices->seed; 2158 } 2159 cur_devices->seed = NULL; 2160 close_fs_devices(cur_devices); 2161 free_fs_devices(cur_devices); 2162 } 2163 2164 out: 2165 mutex_unlock(&uuid_mutex); 2166 return ret; 2167 2168 error_undo: 2169 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { 2170 mutex_lock(&fs_info->chunk_mutex); 2171 list_add(&device->dev_alloc_list, 2172 &fs_devices->alloc_list); 2173 device->fs_devices->rw_devices++; 2174 mutex_unlock(&fs_info->chunk_mutex); 2175 } 2176 goto out; 2177 } 2178 2179 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_device *srcdev) 2180 { 2181 struct btrfs_fs_devices *fs_devices; 2182 2183 lockdep_assert_held(&srcdev->fs_info->fs_devices->device_list_mutex); 2184 2185 /* 2186 * in case of fs with no seed, srcdev->fs_devices will point 2187 * to fs_devices of fs_info. However when the dev being replaced is 2188 * a seed dev it will point to the seed's local fs_devices. In short 2189 * srcdev will have its correct fs_devices in both the cases. 2190 */ 2191 fs_devices = srcdev->fs_devices; 2192 2193 list_del_rcu(&srcdev->dev_list); 2194 list_del(&srcdev->dev_alloc_list); 2195 fs_devices->num_devices--; 2196 if (test_bit(BTRFS_DEV_STATE_MISSING, &srcdev->dev_state)) 2197 fs_devices->missing_devices--; 2198 2199 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state)) 2200 fs_devices->rw_devices--; 2201 2202 if (srcdev->bdev) 2203 fs_devices->open_devices--; 2204 } 2205 2206 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_device *srcdev) 2207 { 2208 struct btrfs_fs_info *fs_info = srcdev->fs_info; 2209 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices; 2210 2211 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state)) { 2212 /* zero out the old super if it is writable */ 2213 btrfs_scratch_superblocks(fs_info, srcdev->bdev, 2214 srcdev->name->str); 2215 } 2216 2217 btrfs_close_bdev(srcdev); 2218 synchronize_rcu(); 2219 btrfs_free_device(srcdev); 2220 2221 /* if this is no devs we rather delete the fs_devices */ 2222 if (!fs_devices->num_devices) { 2223 struct btrfs_fs_devices *tmp_fs_devices; 2224 2225 /* 2226 * On a mounted FS, num_devices can't be zero unless it's a 2227 * seed. In case of a seed device being replaced, the replace 2228 * target added to the sprout FS, so there will be no more 2229 * device left under the seed FS. 2230 */ 2231 ASSERT(fs_devices->seeding); 2232 2233 tmp_fs_devices = fs_info->fs_devices; 2234 while (tmp_fs_devices) { 2235 if (tmp_fs_devices->seed == fs_devices) { 2236 tmp_fs_devices->seed = fs_devices->seed; 2237 break; 2238 } 2239 tmp_fs_devices = tmp_fs_devices->seed; 2240 } 2241 fs_devices->seed = NULL; 2242 close_fs_devices(fs_devices); 2243 free_fs_devices(fs_devices); 2244 } 2245 } 2246 2247 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_device *tgtdev) 2248 { 2249 struct btrfs_fs_devices *fs_devices = tgtdev->fs_info->fs_devices; 2250 2251 mutex_lock(&fs_devices->device_list_mutex); 2252 2253 btrfs_sysfs_remove_devices_dir(fs_devices, tgtdev); 2254 2255 if (tgtdev->bdev) 2256 fs_devices->open_devices--; 2257 2258 fs_devices->num_devices--; 2259 2260 btrfs_assign_next_active_device(tgtdev, NULL); 2261 2262 list_del_rcu(&tgtdev->dev_list); 2263 2264 mutex_unlock(&fs_devices->device_list_mutex); 2265 2266 /* 2267 * The update_dev_time() with in btrfs_scratch_superblocks() 2268 * may lead to a call to btrfs_show_devname() which will try 2269 * to hold device_list_mutex. And here this device 2270 * is already out of device list, so we don't have to hold 2271 * the device_list_mutex lock. 2272 */ 2273 btrfs_scratch_superblocks(tgtdev->fs_info, tgtdev->bdev, 2274 tgtdev->name->str); 2275 2276 btrfs_close_bdev(tgtdev); 2277 synchronize_rcu(); 2278 btrfs_free_device(tgtdev); 2279 } 2280 2281 static struct btrfs_device *btrfs_find_device_by_path( 2282 struct btrfs_fs_info *fs_info, const char *device_path) 2283 { 2284 int ret = 0; 2285 struct btrfs_super_block *disk_super; 2286 u64 devid; 2287 u8 *dev_uuid; 2288 struct block_device *bdev; 2289 struct btrfs_device *device; 2290 2291 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ, 2292 fs_info->bdev_holder, 0, &bdev, &disk_super); 2293 if (ret) 2294 return ERR_PTR(ret); 2295 2296 devid = btrfs_stack_device_id(&disk_super->dev_item); 2297 dev_uuid = disk_super->dev_item.uuid; 2298 if (btrfs_fs_incompat(fs_info, METADATA_UUID)) 2299 device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid, 2300 disk_super->metadata_uuid, true); 2301 else 2302 device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid, 2303 disk_super->fsid, true); 2304 2305 btrfs_release_disk_super(disk_super); 2306 if (!device) 2307 device = ERR_PTR(-ENOENT); 2308 blkdev_put(bdev, FMODE_READ); 2309 return device; 2310 } 2311 2312 /* 2313 * Lookup a device given by device id, or the path if the id is 0. 2314 */ 2315 struct btrfs_device *btrfs_find_device_by_devspec( 2316 struct btrfs_fs_info *fs_info, u64 devid, 2317 const char *device_path) 2318 { 2319 struct btrfs_device *device; 2320 2321 if (devid) { 2322 device = btrfs_find_device(fs_info->fs_devices, devid, NULL, 2323 NULL, true); 2324 if (!device) 2325 return ERR_PTR(-ENOENT); 2326 return device; 2327 } 2328 2329 if (!device_path || !device_path[0]) 2330 return ERR_PTR(-EINVAL); 2331 2332 if (strcmp(device_path, "missing") == 0) { 2333 /* Find first missing device */ 2334 list_for_each_entry(device, &fs_info->fs_devices->devices, 2335 dev_list) { 2336 if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, 2337 &device->dev_state) && !device->bdev) 2338 return device; 2339 } 2340 return ERR_PTR(-ENOENT); 2341 } 2342 2343 return btrfs_find_device_by_path(fs_info, device_path); 2344 } 2345 2346 /* 2347 * does all the dirty work required for changing file system's UUID. 2348 */ 2349 static int btrfs_prepare_sprout(struct btrfs_fs_info *fs_info) 2350 { 2351 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 2352 struct btrfs_fs_devices *old_devices; 2353 struct btrfs_fs_devices *seed_devices; 2354 struct btrfs_super_block *disk_super = fs_info->super_copy; 2355 struct btrfs_device *device; 2356 u64 super_flags; 2357 2358 lockdep_assert_held(&uuid_mutex); 2359 if (!fs_devices->seeding) 2360 return -EINVAL; 2361 2362 seed_devices = alloc_fs_devices(NULL, NULL); 2363 if (IS_ERR(seed_devices)) 2364 return PTR_ERR(seed_devices); 2365 2366 old_devices = clone_fs_devices(fs_devices); 2367 if (IS_ERR(old_devices)) { 2368 kfree(seed_devices); 2369 return PTR_ERR(old_devices); 2370 } 2371 2372 list_add(&old_devices->fs_list, &fs_uuids); 2373 2374 memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); 2375 seed_devices->opened = 1; 2376 INIT_LIST_HEAD(&seed_devices->devices); 2377 INIT_LIST_HEAD(&seed_devices->alloc_list); 2378 mutex_init(&seed_devices->device_list_mutex); 2379 2380 mutex_lock(&fs_devices->device_list_mutex); 2381 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, 2382 synchronize_rcu); 2383 list_for_each_entry(device, &seed_devices->devices, dev_list) 2384 device->fs_devices = seed_devices; 2385 2386 mutex_lock(&fs_info->chunk_mutex); 2387 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); 2388 mutex_unlock(&fs_info->chunk_mutex); 2389 2390 fs_devices->seeding = false; 2391 fs_devices->num_devices = 0; 2392 fs_devices->open_devices = 0; 2393 fs_devices->missing_devices = 0; 2394 fs_devices->rotating = false; 2395 fs_devices->seed = seed_devices; 2396 2397 generate_random_uuid(fs_devices->fsid); 2398 memcpy(fs_devices->metadata_uuid, fs_devices->fsid, BTRFS_FSID_SIZE); 2399 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 2400 mutex_unlock(&fs_devices->device_list_mutex); 2401 2402 super_flags = btrfs_super_flags(disk_super) & 2403 ~BTRFS_SUPER_FLAG_SEEDING; 2404 btrfs_set_super_flags(disk_super, super_flags); 2405 2406 return 0; 2407 } 2408 2409 /* 2410 * Store the expected generation for seed devices in device items. 2411 */ 2412 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans) 2413 { 2414 struct btrfs_fs_info *fs_info = trans->fs_info; 2415 struct btrfs_root *root = fs_info->chunk_root; 2416 struct btrfs_path *path; 2417 struct extent_buffer *leaf; 2418 struct btrfs_dev_item *dev_item; 2419 struct btrfs_device *device; 2420 struct btrfs_key key; 2421 u8 fs_uuid[BTRFS_FSID_SIZE]; 2422 u8 dev_uuid[BTRFS_UUID_SIZE]; 2423 u64 devid; 2424 int ret; 2425 2426 path = btrfs_alloc_path(); 2427 if (!path) 2428 return -ENOMEM; 2429 2430 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 2431 key.offset = 0; 2432 key.type = BTRFS_DEV_ITEM_KEY; 2433 2434 while (1) { 2435 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2436 if (ret < 0) 2437 goto error; 2438 2439 leaf = path->nodes[0]; 2440 next_slot: 2441 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 2442 ret = btrfs_next_leaf(root, path); 2443 if (ret > 0) 2444 break; 2445 if (ret < 0) 2446 goto error; 2447 leaf = path->nodes[0]; 2448 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 2449 btrfs_release_path(path); 2450 continue; 2451 } 2452 2453 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 2454 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || 2455 key.type != BTRFS_DEV_ITEM_KEY) 2456 break; 2457 2458 dev_item = btrfs_item_ptr(leaf, path->slots[0], 2459 struct btrfs_dev_item); 2460 devid = btrfs_device_id(leaf, dev_item); 2461 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item), 2462 BTRFS_UUID_SIZE); 2463 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item), 2464 BTRFS_FSID_SIZE); 2465 device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid, 2466 fs_uuid, true); 2467 BUG_ON(!device); /* Logic error */ 2468 2469 if (device->fs_devices->seeding) { 2470 btrfs_set_device_generation(leaf, dev_item, 2471 device->generation); 2472 btrfs_mark_buffer_dirty(leaf); 2473 } 2474 2475 path->slots[0]++; 2476 goto next_slot; 2477 } 2478 ret = 0; 2479 error: 2480 btrfs_free_path(path); 2481 return ret; 2482 } 2483 2484 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path) 2485 { 2486 struct btrfs_root *root = fs_info->dev_root; 2487 struct request_queue *q; 2488 struct btrfs_trans_handle *trans; 2489 struct btrfs_device *device; 2490 struct block_device *bdev; 2491 struct super_block *sb = fs_info->sb; 2492 struct rcu_string *name; 2493 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 2494 u64 orig_super_total_bytes; 2495 u64 orig_super_num_devices; 2496 int seeding_dev = 0; 2497 int ret = 0; 2498 bool unlocked = false; 2499 2500 if (sb_rdonly(sb) && !fs_devices->seeding) 2501 return -EROFS; 2502 2503 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 2504 fs_info->bdev_holder); 2505 if (IS_ERR(bdev)) 2506 return PTR_ERR(bdev); 2507 2508 if (fs_devices->seeding) { 2509 seeding_dev = 1; 2510 down_write(&sb->s_umount); 2511 mutex_lock(&uuid_mutex); 2512 } 2513 2514 filemap_write_and_wait(bdev->bd_inode->i_mapping); 2515 2516 mutex_lock(&fs_devices->device_list_mutex); 2517 list_for_each_entry(device, &fs_devices->devices, dev_list) { 2518 if (device->bdev == bdev) { 2519 ret = -EEXIST; 2520 mutex_unlock( 2521 &fs_devices->device_list_mutex); 2522 goto error; 2523 } 2524 } 2525 mutex_unlock(&fs_devices->device_list_mutex); 2526 2527 device = btrfs_alloc_device(fs_info, NULL, NULL); 2528 if (IS_ERR(device)) { 2529 /* we can safely leave the fs_devices entry around */ 2530 ret = PTR_ERR(device); 2531 goto error; 2532 } 2533 2534 name = rcu_string_strdup(device_path, GFP_KERNEL); 2535 if (!name) { 2536 ret = -ENOMEM; 2537 goto error_free_device; 2538 } 2539 rcu_assign_pointer(device->name, name); 2540 2541 trans = btrfs_start_transaction(root, 0); 2542 if (IS_ERR(trans)) { 2543 ret = PTR_ERR(trans); 2544 goto error_free_device; 2545 } 2546 2547 q = bdev_get_queue(bdev); 2548 set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); 2549 device->generation = trans->transid; 2550 device->io_width = fs_info->sectorsize; 2551 device->io_align = fs_info->sectorsize; 2552 device->sector_size = fs_info->sectorsize; 2553 device->total_bytes = round_down(i_size_read(bdev->bd_inode), 2554 fs_info->sectorsize); 2555 device->disk_total_bytes = device->total_bytes; 2556 device->commit_total_bytes = device->total_bytes; 2557 device->fs_info = fs_info; 2558 device->bdev = bdev; 2559 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 2560 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); 2561 device->mode = FMODE_EXCL; 2562 device->dev_stats_valid = 1; 2563 set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE); 2564 2565 if (seeding_dev) { 2566 sb->s_flags &= ~SB_RDONLY; 2567 ret = btrfs_prepare_sprout(fs_info); 2568 if (ret) { 2569 btrfs_abort_transaction(trans, ret); 2570 goto error_trans; 2571 } 2572 } 2573 2574 device->fs_devices = fs_devices; 2575 2576 mutex_lock(&fs_devices->device_list_mutex); 2577 mutex_lock(&fs_info->chunk_mutex); 2578 list_add_rcu(&device->dev_list, &fs_devices->devices); 2579 list_add(&device->dev_alloc_list, &fs_devices->alloc_list); 2580 fs_devices->num_devices++; 2581 fs_devices->open_devices++; 2582 fs_devices->rw_devices++; 2583 fs_devices->total_devices++; 2584 fs_devices->total_rw_bytes += device->total_bytes; 2585 2586 atomic64_add(device->total_bytes, &fs_info->free_chunk_space); 2587 2588 if (!blk_queue_nonrot(q)) 2589 fs_devices->rotating = true; 2590 2591 orig_super_total_bytes = btrfs_super_total_bytes(fs_info->super_copy); 2592 btrfs_set_super_total_bytes(fs_info->super_copy, 2593 round_down(orig_super_total_bytes + device->total_bytes, 2594 fs_info->sectorsize)); 2595 2596 orig_super_num_devices = btrfs_super_num_devices(fs_info->super_copy); 2597 btrfs_set_super_num_devices(fs_info->super_copy, 2598 orig_super_num_devices + 1); 2599 2600 /* add sysfs device entry */ 2601 btrfs_sysfs_add_devices_dir(fs_devices, device); 2602 2603 /* 2604 * we've got more storage, clear any full flags on the space 2605 * infos 2606 */ 2607 btrfs_clear_space_info_full(fs_info); 2608 2609 mutex_unlock(&fs_info->chunk_mutex); 2610 mutex_unlock(&fs_devices->device_list_mutex); 2611 2612 if (seeding_dev) { 2613 mutex_lock(&fs_info->chunk_mutex); 2614 ret = init_first_rw_device(trans); 2615 mutex_unlock(&fs_info->chunk_mutex); 2616 if (ret) { 2617 btrfs_abort_transaction(trans, ret); 2618 goto error_sysfs; 2619 } 2620 } 2621 2622 ret = btrfs_add_dev_item(trans, device); 2623 if (ret) { 2624 btrfs_abort_transaction(trans, ret); 2625 goto error_sysfs; 2626 } 2627 2628 if (seeding_dev) { 2629 ret = btrfs_finish_sprout(trans); 2630 if (ret) { 2631 btrfs_abort_transaction(trans, ret); 2632 goto error_sysfs; 2633 } 2634 2635 btrfs_sysfs_update_sprout_fsid(fs_devices, 2636 fs_info->fs_devices->fsid); 2637 } 2638 2639 ret = btrfs_commit_transaction(trans); 2640 2641 if (seeding_dev) { 2642 mutex_unlock(&uuid_mutex); 2643 up_write(&sb->s_umount); 2644 unlocked = true; 2645 2646 if (ret) /* transaction commit */ 2647 return ret; 2648 2649 ret = btrfs_relocate_sys_chunks(fs_info); 2650 if (ret < 0) 2651 btrfs_handle_fs_error(fs_info, ret, 2652 "Failed to relocate sys chunks after device initialization. This can be fixed using the \"btrfs balance\" command."); 2653 trans = btrfs_attach_transaction(root); 2654 if (IS_ERR(trans)) { 2655 if (PTR_ERR(trans) == -ENOENT) 2656 return 0; 2657 ret = PTR_ERR(trans); 2658 trans = NULL; 2659 goto error_sysfs; 2660 } 2661 ret = btrfs_commit_transaction(trans); 2662 } 2663 2664 /* 2665 * Now that we have written a new super block to this device, check all 2666 * other fs_devices list if device_path alienates any other scanned 2667 * device. 2668 * We can ignore the return value as it typically returns -EINVAL and 2669 * only succeeds if the device was an alien. 2670 */ 2671 btrfs_forget_devices(device_path); 2672 2673 /* Update ctime/mtime for blkid or udev */ 2674 update_dev_time(device_path); 2675 2676 return ret; 2677 2678 error_sysfs: 2679 btrfs_sysfs_remove_devices_dir(fs_devices, device); 2680 mutex_lock(&fs_info->fs_devices->device_list_mutex); 2681 mutex_lock(&fs_info->chunk_mutex); 2682 list_del_rcu(&device->dev_list); 2683 list_del(&device->dev_alloc_list); 2684 fs_info->fs_devices->num_devices--; 2685 fs_info->fs_devices->open_devices--; 2686 fs_info->fs_devices->rw_devices--; 2687 fs_info->fs_devices->total_devices--; 2688 fs_info->fs_devices->total_rw_bytes -= device->total_bytes; 2689 atomic64_sub(device->total_bytes, &fs_info->free_chunk_space); 2690 btrfs_set_super_total_bytes(fs_info->super_copy, 2691 orig_super_total_bytes); 2692 btrfs_set_super_num_devices(fs_info->super_copy, 2693 orig_super_num_devices); 2694 mutex_unlock(&fs_info->chunk_mutex); 2695 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 2696 error_trans: 2697 if (seeding_dev) 2698 sb->s_flags |= SB_RDONLY; 2699 if (trans) 2700 btrfs_end_transaction(trans); 2701 error_free_device: 2702 btrfs_free_device(device); 2703 error: 2704 blkdev_put(bdev, FMODE_EXCL); 2705 if (seeding_dev && !unlocked) { 2706 mutex_unlock(&uuid_mutex); 2707 up_write(&sb->s_umount); 2708 } 2709 return ret; 2710 } 2711 2712 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, 2713 struct btrfs_device *device) 2714 { 2715 int ret; 2716 struct btrfs_path *path; 2717 struct btrfs_root *root = device->fs_info->chunk_root; 2718 struct btrfs_dev_item *dev_item; 2719 struct extent_buffer *leaf; 2720 struct btrfs_key key; 2721 2722 path = btrfs_alloc_path(); 2723 if (!path) 2724 return -ENOMEM; 2725 2726 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 2727 key.type = BTRFS_DEV_ITEM_KEY; 2728 key.offset = device->devid; 2729 2730 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2731 if (ret < 0) 2732 goto out; 2733 2734 if (ret > 0) { 2735 ret = -ENOENT; 2736 goto out; 2737 } 2738 2739 leaf = path->nodes[0]; 2740 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 2741 2742 btrfs_set_device_id(leaf, dev_item, device->devid); 2743 btrfs_set_device_type(leaf, dev_item, device->type); 2744 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 2745 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 2746 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 2747 btrfs_set_device_total_bytes(leaf, dev_item, 2748 btrfs_device_get_disk_total_bytes(device)); 2749 btrfs_set_device_bytes_used(leaf, dev_item, 2750 btrfs_device_get_bytes_used(device)); 2751 btrfs_mark_buffer_dirty(leaf); 2752 2753 out: 2754 btrfs_free_path(path); 2755 return ret; 2756 } 2757 2758 int btrfs_grow_device(struct btrfs_trans_handle *trans, 2759 struct btrfs_device *device, u64 new_size) 2760 { 2761 struct btrfs_fs_info *fs_info = device->fs_info; 2762 struct btrfs_super_block *super_copy = fs_info->super_copy; 2763 u64 old_total; 2764 u64 diff; 2765 2766 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) 2767 return -EACCES; 2768 2769 new_size = round_down(new_size, fs_info->sectorsize); 2770 2771 mutex_lock(&fs_info->chunk_mutex); 2772 old_total = btrfs_super_total_bytes(super_copy); 2773 diff = round_down(new_size - device->total_bytes, fs_info->sectorsize); 2774 2775 if (new_size <= device->total_bytes || 2776 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { 2777 mutex_unlock(&fs_info->chunk_mutex); 2778 return -EINVAL; 2779 } 2780 2781 btrfs_set_super_total_bytes(super_copy, 2782 round_down(old_total + diff, fs_info->sectorsize)); 2783 device->fs_devices->total_rw_bytes += diff; 2784 2785 btrfs_device_set_total_bytes(device, new_size); 2786 btrfs_device_set_disk_total_bytes(device, new_size); 2787 btrfs_clear_space_info_full(device->fs_info); 2788 if (list_empty(&device->post_commit_list)) 2789 list_add_tail(&device->post_commit_list, 2790 &trans->transaction->dev_update_list); 2791 mutex_unlock(&fs_info->chunk_mutex); 2792 2793 return btrfs_update_device(trans, device); 2794 } 2795 2796 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset) 2797 { 2798 struct btrfs_fs_info *fs_info = trans->fs_info; 2799 struct btrfs_root *root = fs_info->chunk_root; 2800 int ret; 2801 struct btrfs_path *path; 2802 struct btrfs_key key; 2803 2804 path = btrfs_alloc_path(); 2805 if (!path) 2806 return -ENOMEM; 2807 2808 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2809 key.offset = chunk_offset; 2810 key.type = BTRFS_CHUNK_ITEM_KEY; 2811 2812 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2813 if (ret < 0) 2814 goto out; 2815 else if (ret > 0) { /* Logic error or corruption */ 2816 btrfs_handle_fs_error(fs_info, -ENOENT, 2817 "Failed lookup while freeing chunk."); 2818 ret = -ENOENT; 2819 goto out; 2820 } 2821 2822 ret = btrfs_del_item(trans, root, path); 2823 if (ret < 0) 2824 btrfs_handle_fs_error(fs_info, ret, 2825 "Failed to delete chunk item."); 2826 out: 2827 btrfs_free_path(path); 2828 return ret; 2829 } 2830 2831 static int btrfs_del_sys_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset) 2832 { 2833 struct btrfs_super_block *super_copy = fs_info->super_copy; 2834 struct btrfs_disk_key *disk_key; 2835 struct btrfs_chunk *chunk; 2836 u8 *ptr; 2837 int ret = 0; 2838 u32 num_stripes; 2839 u32 array_size; 2840 u32 len = 0; 2841 u32 cur; 2842 struct btrfs_key key; 2843 2844 mutex_lock(&fs_info->chunk_mutex); 2845 array_size = btrfs_super_sys_array_size(super_copy); 2846 2847 ptr = super_copy->sys_chunk_array; 2848 cur = 0; 2849 2850 while (cur < array_size) { 2851 disk_key = (struct btrfs_disk_key *)ptr; 2852 btrfs_disk_key_to_cpu(&key, disk_key); 2853 2854 len = sizeof(*disk_key); 2855 2856 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 2857 chunk = (struct btrfs_chunk *)(ptr + len); 2858 num_stripes = btrfs_stack_chunk_num_stripes(chunk); 2859 len += btrfs_chunk_item_size(num_stripes); 2860 } else { 2861 ret = -EIO; 2862 break; 2863 } 2864 if (key.objectid == BTRFS_FIRST_CHUNK_TREE_OBJECTID && 2865 key.offset == chunk_offset) { 2866 memmove(ptr, ptr + len, array_size - (cur + len)); 2867 array_size -= len; 2868 btrfs_set_super_sys_array_size(super_copy, array_size); 2869 } else { 2870 ptr += len; 2871 cur += len; 2872 } 2873 } 2874 mutex_unlock(&fs_info->chunk_mutex); 2875 return ret; 2876 } 2877 2878 /* 2879 * btrfs_get_chunk_map() - Find the mapping containing the given logical extent. 2880 * @logical: Logical block offset in bytes. 2881 * @length: Length of extent in bytes. 2882 * 2883 * Return: Chunk mapping or ERR_PTR. 2884 */ 2885 struct extent_map *btrfs_get_chunk_map(struct btrfs_fs_info *fs_info, 2886 u64 logical, u64 length) 2887 { 2888 struct extent_map_tree *em_tree; 2889 struct extent_map *em; 2890 2891 em_tree = &fs_info->mapping_tree; 2892 read_lock(&em_tree->lock); 2893 em = lookup_extent_mapping(em_tree, logical, length); 2894 read_unlock(&em_tree->lock); 2895 2896 if (!em) { 2897 btrfs_crit(fs_info, "unable to find logical %llu length %llu", 2898 logical, length); 2899 return ERR_PTR(-EINVAL); 2900 } 2901 2902 if (em->start > logical || em->start + em->len < logical) { 2903 btrfs_crit(fs_info, 2904 "found a bad mapping, wanted %llu-%llu, found %llu-%llu", 2905 logical, length, em->start, em->start + em->len); 2906 free_extent_map(em); 2907 return ERR_PTR(-EINVAL); 2908 } 2909 2910 /* callers are responsible for dropping em's ref. */ 2911 return em; 2912 } 2913 2914 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset) 2915 { 2916 struct btrfs_fs_info *fs_info = trans->fs_info; 2917 struct extent_map *em; 2918 struct map_lookup *map; 2919 u64 dev_extent_len = 0; 2920 int i, ret = 0; 2921 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 2922 2923 em = btrfs_get_chunk_map(fs_info, chunk_offset, 1); 2924 if (IS_ERR(em)) { 2925 /* 2926 * This is a logic error, but we don't want to just rely on the 2927 * user having built with ASSERT enabled, so if ASSERT doesn't 2928 * do anything we still error out. 2929 */ 2930 ASSERT(0); 2931 return PTR_ERR(em); 2932 } 2933 map = em->map_lookup; 2934 mutex_lock(&fs_info->chunk_mutex); 2935 check_system_chunk(trans, map->type); 2936 mutex_unlock(&fs_info->chunk_mutex); 2937 2938 /* 2939 * Take the device list mutex to prevent races with the final phase of 2940 * a device replace operation that replaces the device object associated 2941 * with map stripes (dev-replace.c:btrfs_dev_replace_finishing()). 2942 */ 2943 mutex_lock(&fs_devices->device_list_mutex); 2944 for (i = 0; i < map->num_stripes; i++) { 2945 struct btrfs_device *device = map->stripes[i].dev; 2946 ret = btrfs_free_dev_extent(trans, device, 2947 map->stripes[i].physical, 2948 &dev_extent_len); 2949 if (ret) { 2950 mutex_unlock(&fs_devices->device_list_mutex); 2951 btrfs_abort_transaction(trans, ret); 2952 goto out; 2953 } 2954 2955 if (device->bytes_used > 0) { 2956 mutex_lock(&fs_info->chunk_mutex); 2957 btrfs_device_set_bytes_used(device, 2958 device->bytes_used - dev_extent_len); 2959 atomic64_add(dev_extent_len, &fs_info->free_chunk_space); 2960 btrfs_clear_space_info_full(fs_info); 2961 mutex_unlock(&fs_info->chunk_mutex); 2962 } 2963 2964 ret = btrfs_update_device(trans, device); 2965 if (ret) { 2966 mutex_unlock(&fs_devices->device_list_mutex); 2967 btrfs_abort_transaction(trans, ret); 2968 goto out; 2969 } 2970 } 2971 mutex_unlock(&fs_devices->device_list_mutex); 2972 2973 ret = btrfs_free_chunk(trans, chunk_offset); 2974 if (ret) { 2975 btrfs_abort_transaction(trans, ret); 2976 goto out; 2977 } 2978 2979 trace_btrfs_chunk_free(fs_info, map, chunk_offset, em->len); 2980 2981 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 2982 ret = btrfs_del_sys_chunk(fs_info, chunk_offset); 2983 if (ret) { 2984 btrfs_abort_transaction(trans, ret); 2985 goto out; 2986 } 2987 } 2988 2989 ret = btrfs_remove_block_group(trans, chunk_offset, em); 2990 if (ret) { 2991 btrfs_abort_transaction(trans, ret); 2992 goto out; 2993 } 2994 2995 out: 2996 /* once for us */ 2997 free_extent_map(em); 2998 return ret; 2999 } 3000 3001 static int btrfs_relocate_chunk(struct btrfs_fs_info *fs_info, u64 chunk_offset) 3002 { 3003 struct btrfs_root *root = fs_info->chunk_root; 3004 struct btrfs_trans_handle *trans; 3005 struct btrfs_block_group *block_group; 3006 int ret; 3007 3008 /* 3009 * Prevent races with automatic removal of unused block groups. 3010 * After we relocate and before we remove the chunk with offset 3011 * chunk_offset, automatic removal of the block group can kick in, 3012 * resulting in a failure when calling btrfs_remove_chunk() below. 3013 * 3014 * Make sure to acquire this mutex before doing a tree search (dev 3015 * or chunk trees) to find chunks. Otherwise the cleaner kthread might 3016 * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after 3017 * we release the path used to search the chunk/dev tree and before 3018 * the current task acquires this mutex and calls us. 3019 */ 3020 lockdep_assert_held(&fs_info->delete_unused_bgs_mutex); 3021 3022 /* step one, relocate all the extents inside this chunk */ 3023 btrfs_scrub_pause(fs_info); 3024 ret = btrfs_relocate_block_group(fs_info, chunk_offset); 3025 btrfs_scrub_continue(fs_info); 3026 if (ret) 3027 return ret; 3028 3029 block_group = btrfs_lookup_block_group(fs_info, chunk_offset); 3030 if (!block_group) 3031 return -ENOENT; 3032 btrfs_discard_cancel_work(&fs_info->discard_ctl, block_group); 3033 btrfs_put_block_group(block_group); 3034 3035 trans = btrfs_start_trans_remove_block_group(root->fs_info, 3036 chunk_offset); 3037 if (IS_ERR(trans)) { 3038 ret = PTR_ERR(trans); 3039 btrfs_handle_fs_error(root->fs_info, ret, NULL); 3040 return ret; 3041 } 3042 3043 /* 3044 * step two, delete the device extents and the 3045 * chunk tree entries 3046 */ 3047 ret = btrfs_remove_chunk(trans, chunk_offset); 3048 btrfs_end_transaction(trans); 3049 return ret; 3050 } 3051 3052 static int btrfs_relocate_sys_chunks(struct btrfs_fs_info *fs_info) 3053 { 3054 struct btrfs_root *chunk_root = fs_info->chunk_root; 3055 struct btrfs_path *path; 3056 struct extent_buffer *leaf; 3057 struct btrfs_chunk *chunk; 3058 struct btrfs_key key; 3059 struct btrfs_key found_key; 3060 u64 chunk_type; 3061 bool retried = false; 3062 int failed = 0; 3063 int ret; 3064 3065 path = btrfs_alloc_path(); 3066 if (!path) 3067 return -ENOMEM; 3068 3069 again: 3070 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 3071 key.offset = (u64)-1; 3072 key.type = BTRFS_CHUNK_ITEM_KEY; 3073 3074 while (1) { 3075 mutex_lock(&fs_info->delete_unused_bgs_mutex); 3076 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 3077 if (ret < 0) { 3078 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3079 goto error; 3080 } 3081 BUG_ON(ret == 0); /* Corruption */ 3082 3083 ret = btrfs_previous_item(chunk_root, path, key.objectid, 3084 key.type); 3085 if (ret) 3086 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3087 if (ret < 0) 3088 goto error; 3089 if (ret > 0) 3090 break; 3091 3092 leaf = path->nodes[0]; 3093 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 3094 3095 chunk = btrfs_item_ptr(leaf, path->slots[0], 3096 struct btrfs_chunk); 3097 chunk_type = btrfs_chunk_type(leaf, chunk); 3098 btrfs_release_path(path); 3099 3100 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { 3101 ret = btrfs_relocate_chunk(fs_info, found_key.offset); 3102 if (ret == -ENOSPC) 3103 failed++; 3104 else 3105 BUG_ON(ret); 3106 } 3107 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3108 3109 if (found_key.offset == 0) 3110 break; 3111 key.offset = found_key.offset - 1; 3112 } 3113 ret = 0; 3114 if (failed && !retried) { 3115 failed = 0; 3116 retried = true; 3117 goto again; 3118 } else if (WARN_ON(failed && retried)) { 3119 ret = -ENOSPC; 3120 } 3121 error: 3122 btrfs_free_path(path); 3123 return ret; 3124 } 3125 3126 /* 3127 * return 1 : allocate a data chunk successfully, 3128 * return <0: errors during allocating a data chunk, 3129 * return 0 : no need to allocate a data chunk. 3130 */ 3131 static int btrfs_may_alloc_data_chunk(struct btrfs_fs_info *fs_info, 3132 u64 chunk_offset) 3133 { 3134 struct btrfs_block_group *cache; 3135 u64 bytes_used; 3136 u64 chunk_type; 3137 3138 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 3139 ASSERT(cache); 3140 chunk_type = cache->flags; 3141 btrfs_put_block_group(cache); 3142 3143 if (!(chunk_type & BTRFS_BLOCK_GROUP_DATA)) 3144 return 0; 3145 3146 spin_lock(&fs_info->data_sinfo->lock); 3147 bytes_used = fs_info->data_sinfo->bytes_used; 3148 spin_unlock(&fs_info->data_sinfo->lock); 3149 3150 if (!bytes_used) { 3151 struct btrfs_trans_handle *trans; 3152 int ret; 3153 3154 trans = btrfs_join_transaction(fs_info->tree_root); 3155 if (IS_ERR(trans)) 3156 return PTR_ERR(trans); 3157 3158 ret = btrfs_force_chunk_alloc(trans, BTRFS_BLOCK_GROUP_DATA); 3159 btrfs_end_transaction(trans); 3160 if (ret < 0) 3161 return ret; 3162 return 1; 3163 } 3164 3165 return 0; 3166 } 3167 3168 static int insert_balance_item(struct btrfs_fs_info *fs_info, 3169 struct btrfs_balance_control *bctl) 3170 { 3171 struct btrfs_root *root = fs_info->tree_root; 3172 struct btrfs_trans_handle *trans; 3173 struct btrfs_balance_item *item; 3174 struct btrfs_disk_balance_args disk_bargs; 3175 struct btrfs_path *path; 3176 struct extent_buffer *leaf; 3177 struct btrfs_key key; 3178 int ret, err; 3179 3180 path = btrfs_alloc_path(); 3181 if (!path) 3182 return -ENOMEM; 3183 3184 trans = btrfs_start_transaction(root, 0); 3185 if (IS_ERR(trans)) { 3186 btrfs_free_path(path); 3187 return PTR_ERR(trans); 3188 } 3189 3190 key.objectid = BTRFS_BALANCE_OBJECTID; 3191 key.type = BTRFS_TEMPORARY_ITEM_KEY; 3192 key.offset = 0; 3193 3194 ret = btrfs_insert_empty_item(trans, root, path, &key, 3195 sizeof(*item)); 3196 if (ret) 3197 goto out; 3198 3199 leaf = path->nodes[0]; 3200 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 3201 3202 memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item)); 3203 3204 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); 3205 btrfs_set_balance_data(leaf, item, &disk_bargs); 3206 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); 3207 btrfs_set_balance_meta(leaf, item, &disk_bargs); 3208 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); 3209 btrfs_set_balance_sys(leaf, item, &disk_bargs); 3210 3211 btrfs_set_balance_flags(leaf, item, bctl->flags); 3212 3213 btrfs_mark_buffer_dirty(leaf); 3214 out: 3215 btrfs_free_path(path); 3216 err = btrfs_commit_transaction(trans); 3217 if (err && !ret) 3218 ret = err; 3219 return ret; 3220 } 3221 3222 static int del_balance_item(struct btrfs_fs_info *fs_info) 3223 { 3224 struct btrfs_root *root = fs_info->tree_root; 3225 struct btrfs_trans_handle *trans; 3226 struct btrfs_path *path; 3227 struct btrfs_key key; 3228 int ret, err; 3229 3230 path = btrfs_alloc_path(); 3231 if (!path) 3232 return -ENOMEM; 3233 3234 trans = btrfs_start_transaction(root, 0); 3235 if (IS_ERR(trans)) { 3236 btrfs_free_path(path); 3237 return PTR_ERR(trans); 3238 } 3239 3240 key.objectid = BTRFS_BALANCE_OBJECTID; 3241 key.type = BTRFS_TEMPORARY_ITEM_KEY; 3242 key.offset = 0; 3243 3244 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 3245 if (ret < 0) 3246 goto out; 3247 if (ret > 0) { 3248 ret = -ENOENT; 3249 goto out; 3250 } 3251 3252 ret = btrfs_del_item(trans, root, path); 3253 out: 3254 btrfs_free_path(path); 3255 err = btrfs_commit_transaction(trans); 3256 if (err && !ret) 3257 ret = err; 3258 return ret; 3259 } 3260 3261 /* 3262 * This is a heuristic used to reduce the number of chunks balanced on 3263 * resume after balance was interrupted. 3264 */ 3265 static void update_balance_args(struct btrfs_balance_control *bctl) 3266 { 3267 /* 3268 * Turn on soft mode for chunk types that were being converted. 3269 */ 3270 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) 3271 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; 3272 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) 3273 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; 3274 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) 3275 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; 3276 3277 /* 3278 * Turn on usage filter if is not already used. The idea is 3279 * that chunks that we have already balanced should be 3280 * reasonably full. Don't do it for chunks that are being 3281 * converted - that will keep us from relocating unconverted 3282 * (albeit full) chunks. 3283 */ 3284 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && 3285 !(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) && 3286 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 3287 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; 3288 bctl->data.usage = 90; 3289 } 3290 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && 3291 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) && 3292 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 3293 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; 3294 bctl->sys.usage = 90; 3295 } 3296 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && 3297 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) && 3298 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 3299 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; 3300 bctl->meta.usage = 90; 3301 } 3302 } 3303 3304 /* 3305 * Clear the balance status in fs_info and delete the balance item from disk. 3306 */ 3307 static void reset_balance_state(struct btrfs_fs_info *fs_info) 3308 { 3309 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3310 int ret; 3311 3312 BUG_ON(!fs_info->balance_ctl); 3313 3314 spin_lock(&fs_info->balance_lock); 3315 fs_info->balance_ctl = NULL; 3316 spin_unlock(&fs_info->balance_lock); 3317 3318 kfree(bctl); 3319 ret = del_balance_item(fs_info); 3320 if (ret) 3321 btrfs_handle_fs_error(fs_info, ret, NULL); 3322 } 3323 3324 /* 3325 * Balance filters. Return 1 if chunk should be filtered out 3326 * (should not be balanced). 3327 */ 3328 static int chunk_profiles_filter(u64 chunk_type, 3329 struct btrfs_balance_args *bargs) 3330 { 3331 chunk_type = chunk_to_extended(chunk_type) & 3332 BTRFS_EXTENDED_PROFILE_MASK; 3333 3334 if (bargs->profiles & chunk_type) 3335 return 0; 3336 3337 return 1; 3338 } 3339 3340 static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, 3341 struct btrfs_balance_args *bargs) 3342 { 3343 struct btrfs_block_group *cache; 3344 u64 chunk_used; 3345 u64 user_thresh_min; 3346 u64 user_thresh_max; 3347 int ret = 1; 3348 3349 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 3350 chunk_used = cache->used; 3351 3352 if (bargs->usage_min == 0) 3353 user_thresh_min = 0; 3354 else 3355 user_thresh_min = div_factor_fine(cache->length, 3356 bargs->usage_min); 3357 3358 if (bargs->usage_max == 0) 3359 user_thresh_max = 1; 3360 else if (bargs->usage_max > 100) 3361 user_thresh_max = cache->length; 3362 else 3363 user_thresh_max = div_factor_fine(cache->length, 3364 bargs->usage_max); 3365 3366 if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max) 3367 ret = 0; 3368 3369 btrfs_put_block_group(cache); 3370 return ret; 3371 } 3372 3373 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, 3374 u64 chunk_offset, struct btrfs_balance_args *bargs) 3375 { 3376 struct btrfs_block_group *cache; 3377 u64 chunk_used, user_thresh; 3378 int ret = 1; 3379 3380 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 3381 chunk_used = cache->used; 3382 3383 if (bargs->usage_min == 0) 3384 user_thresh = 1; 3385 else if (bargs->usage > 100) 3386 user_thresh = cache->length; 3387 else 3388 user_thresh = div_factor_fine(cache->length, bargs->usage); 3389 3390 if (chunk_used < user_thresh) 3391 ret = 0; 3392 3393 btrfs_put_block_group(cache); 3394 return ret; 3395 } 3396 3397 static int chunk_devid_filter(struct extent_buffer *leaf, 3398 struct btrfs_chunk *chunk, 3399 struct btrfs_balance_args *bargs) 3400 { 3401 struct btrfs_stripe *stripe; 3402 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 3403 int i; 3404 3405 for (i = 0; i < num_stripes; i++) { 3406 stripe = btrfs_stripe_nr(chunk, i); 3407 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) 3408 return 0; 3409 } 3410 3411 return 1; 3412 } 3413 3414 static u64 calc_data_stripes(u64 type, int num_stripes) 3415 { 3416 const int index = btrfs_bg_flags_to_raid_index(type); 3417 const int ncopies = btrfs_raid_array[index].ncopies; 3418 const int nparity = btrfs_raid_array[index].nparity; 3419 3420 if (nparity) 3421 return num_stripes - nparity; 3422 else 3423 return num_stripes / ncopies; 3424 } 3425 3426 /* [pstart, pend) */ 3427 static int chunk_drange_filter(struct extent_buffer *leaf, 3428 struct btrfs_chunk *chunk, 3429 struct btrfs_balance_args *bargs) 3430 { 3431 struct btrfs_stripe *stripe; 3432 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 3433 u64 stripe_offset; 3434 u64 stripe_length; 3435 u64 type; 3436 int factor; 3437 int i; 3438 3439 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) 3440 return 0; 3441 3442 type = btrfs_chunk_type(leaf, chunk); 3443 factor = calc_data_stripes(type, num_stripes); 3444 3445 for (i = 0; i < num_stripes; i++) { 3446 stripe = btrfs_stripe_nr(chunk, i); 3447 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) 3448 continue; 3449 3450 stripe_offset = btrfs_stripe_offset(leaf, stripe); 3451 stripe_length = btrfs_chunk_length(leaf, chunk); 3452 stripe_length = div_u64(stripe_length, factor); 3453 3454 if (stripe_offset < bargs->pend && 3455 stripe_offset + stripe_length > bargs->pstart) 3456 return 0; 3457 } 3458 3459 return 1; 3460 } 3461 3462 /* [vstart, vend) */ 3463 static int chunk_vrange_filter(struct extent_buffer *leaf, 3464 struct btrfs_chunk *chunk, 3465 u64 chunk_offset, 3466 struct btrfs_balance_args *bargs) 3467 { 3468 if (chunk_offset < bargs->vend && 3469 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) 3470 /* at least part of the chunk is inside this vrange */ 3471 return 0; 3472 3473 return 1; 3474 } 3475 3476 static int chunk_stripes_range_filter(struct extent_buffer *leaf, 3477 struct btrfs_chunk *chunk, 3478 struct btrfs_balance_args *bargs) 3479 { 3480 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 3481 3482 if (bargs->stripes_min <= num_stripes 3483 && num_stripes <= bargs->stripes_max) 3484 return 0; 3485 3486 return 1; 3487 } 3488 3489 static int chunk_soft_convert_filter(u64 chunk_type, 3490 struct btrfs_balance_args *bargs) 3491 { 3492 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) 3493 return 0; 3494 3495 chunk_type = chunk_to_extended(chunk_type) & 3496 BTRFS_EXTENDED_PROFILE_MASK; 3497 3498 if (bargs->target == chunk_type) 3499 return 1; 3500 3501 return 0; 3502 } 3503 3504 static int should_balance_chunk(struct extent_buffer *leaf, 3505 struct btrfs_chunk *chunk, u64 chunk_offset) 3506 { 3507 struct btrfs_fs_info *fs_info = leaf->fs_info; 3508 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3509 struct btrfs_balance_args *bargs = NULL; 3510 u64 chunk_type = btrfs_chunk_type(leaf, chunk); 3511 3512 /* type filter */ 3513 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & 3514 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { 3515 return 0; 3516 } 3517 3518 if (chunk_type & BTRFS_BLOCK_GROUP_DATA) 3519 bargs = &bctl->data; 3520 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) 3521 bargs = &bctl->sys; 3522 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) 3523 bargs = &bctl->meta; 3524 3525 /* profiles filter */ 3526 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && 3527 chunk_profiles_filter(chunk_type, bargs)) { 3528 return 0; 3529 } 3530 3531 /* usage filter */ 3532 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && 3533 chunk_usage_filter(fs_info, chunk_offset, bargs)) { 3534 return 0; 3535 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) && 3536 chunk_usage_range_filter(fs_info, chunk_offset, bargs)) { 3537 return 0; 3538 } 3539 3540 /* devid filter */ 3541 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && 3542 chunk_devid_filter(leaf, chunk, bargs)) { 3543 return 0; 3544 } 3545 3546 /* drange filter, makes sense only with devid filter */ 3547 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && 3548 chunk_drange_filter(leaf, chunk, bargs)) { 3549 return 0; 3550 } 3551 3552 /* vrange filter */ 3553 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && 3554 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { 3555 return 0; 3556 } 3557 3558 /* stripes filter */ 3559 if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) && 3560 chunk_stripes_range_filter(leaf, chunk, bargs)) { 3561 return 0; 3562 } 3563 3564 /* soft profile changing mode */ 3565 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && 3566 chunk_soft_convert_filter(chunk_type, bargs)) { 3567 return 0; 3568 } 3569 3570 /* 3571 * limited by count, must be the last filter 3572 */ 3573 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) { 3574 if (bargs->limit == 0) 3575 return 0; 3576 else 3577 bargs->limit--; 3578 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) { 3579 /* 3580 * Same logic as the 'limit' filter; the minimum cannot be 3581 * determined here because we do not have the global information 3582 * about the count of all chunks that satisfy the filters. 3583 */ 3584 if (bargs->limit_max == 0) 3585 return 0; 3586 else 3587 bargs->limit_max--; 3588 } 3589 3590 return 1; 3591 } 3592 3593 static int __btrfs_balance(struct btrfs_fs_info *fs_info) 3594 { 3595 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3596 struct btrfs_root *chunk_root = fs_info->chunk_root; 3597 u64 chunk_type; 3598 struct btrfs_chunk *chunk; 3599 struct btrfs_path *path = NULL; 3600 struct btrfs_key key; 3601 struct btrfs_key found_key; 3602 struct extent_buffer *leaf; 3603 int slot; 3604 int ret; 3605 int enospc_errors = 0; 3606 bool counting = true; 3607 /* The single value limit and min/max limits use the same bytes in the */ 3608 u64 limit_data = bctl->data.limit; 3609 u64 limit_meta = bctl->meta.limit; 3610 u64 limit_sys = bctl->sys.limit; 3611 u32 count_data = 0; 3612 u32 count_meta = 0; 3613 u32 count_sys = 0; 3614 int chunk_reserved = 0; 3615 3616 path = btrfs_alloc_path(); 3617 if (!path) { 3618 ret = -ENOMEM; 3619 goto error; 3620 } 3621 3622 /* zero out stat counters */ 3623 spin_lock(&fs_info->balance_lock); 3624 memset(&bctl->stat, 0, sizeof(bctl->stat)); 3625 spin_unlock(&fs_info->balance_lock); 3626 again: 3627 if (!counting) { 3628 /* 3629 * The single value limit and min/max limits use the same bytes 3630 * in the 3631 */ 3632 bctl->data.limit = limit_data; 3633 bctl->meta.limit = limit_meta; 3634 bctl->sys.limit = limit_sys; 3635 } 3636 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 3637 key.offset = (u64)-1; 3638 key.type = BTRFS_CHUNK_ITEM_KEY; 3639 3640 while (1) { 3641 if ((!counting && atomic_read(&fs_info->balance_pause_req)) || 3642 atomic_read(&fs_info->balance_cancel_req)) { 3643 ret = -ECANCELED; 3644 goto error; 3645 } 3646 3647 mutex_lock(&fs_info->delete_unused_bgs_mutex); 3648 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 3649 if (ret < 0) { 3650 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3651 goto error; 3652 } 3653 3654 /* 3655 * this shouldn't happen, it means the last relocate 3656 * failed 3657 */ 3658 if (ret == 0) 3659 BUG(); /* FIXME break ? */ 3660 3661 ret = btrfs_previous_item(chunk_root, path, 0, 3662 BTRFS_CHUNK_ITEM_KEY); 3663 if (ret) { 3664 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3665 ret = 0; 3666 break; 3667 } 3668 3669 leaf = path->nodes[0]; 3670 slot = path->slots[0]; 3671 btrfs_item_key_to_cpu(leaf, &found_key, slot); 3672 3673 if (found_key.objectid != key.objectid) { 3674 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3675 break; 3676 } 3677 3678 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 3679 chunk_type = btrfs_chunk_type(leaf, chunk); 3680 3681 if (!counting) { 3682 spin_lock(&fs_info->balance_lock); 3683 bctl->stat.considered++; 3684 spin_unlock(&fs_info->balance_lock); 3685 } 3686 3687 ret = should_balance_chunk(leaf, chunk, found_key.offset); 3688 3689 btrfs_release_path(path); 3690 if (!ret) { 3691 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3692 goto loop; 3693 } 3694 3695 if (counting) { 3696 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3697 spin_lock(&fs_info->balance_lock); 3698 bctl->stat.expected++; 3699 spin_unlock(&fs_info->balance_lock); 3700 3701 if (chunk_type & BTRFS_BLOCK_GROUP_DATA) 3702 count_data++; 3703 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) 3704 count_sys++; 3705 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) 3706 count_meta++; 3707 3708 goto loop; 3709 } 3710 3711 /* 3712 * Apply limit_min filter, no need to check if the LIMITS 3713 * filter is used, limit_min is 0 by default 3714 */ 3715 if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) && 3716 count_data < bctl->data.limit_min) 3717 || ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) && 3718 count_meta < bctl->meta.limit_min) 3719 || ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) && 3720 count_sys < bctl->sys.limit_min)) { 3721 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3722 goto loop; 3723 } 3724 3725 if (!chunk_reserved) { 3726 /* 3727 * We may be relocating the only data chunk we have, 3728 * which could potentially end up with losing data's 3729 * raid profile, so lets allocate an empty one in 3730 * advance. 3731 */ 3732 ret = btrfs_may_alloc_data_chunk(fs_info, 3733 found_key.offset); 3734 if (ret < 0) { 3735 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3736 goto error; 3737 } else if (ret == 1) { 3738 chunk_reserved = 1; 3739 } 3740 } 3741 3742 ret = btrfs_relocate_chunk(fs_info, found_key.offset); 3743 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 3744 if (ret == -ENOSPC) { 3745 enospc_errors++; 3746 } else if (ret == -ETXTBSY) { 3747 btrfs_info(fs_info, 3748 "skipping relocation of block group %llu due to active swapfile", 3749 found_key.offset); 3750 ret = 0; 3751 } else if (ret) { 3752 goto error; 3753 } else { 3754 spin_lock(&fs_info->balance_lock); 3755 bctl->stat.completed++; 3756 spin_unlock(&fs_info->balance_lock); 3757 } 3758 loop: 3759 if (found_key.offset == 0) 3760 break; 3761 key.offset = found_key.offset - 1; 3762 } 3763 3764 if (counting) { 3765 btrfs_release_path(path); 3766 counting = false; 3767 goto again; 3768 } 3769 error: 3770 btrfs_free_path(path); 3771 if (enospc_errors) { 3772 btrfs_info(fs_info, "%d enospc errors during balance", 3773 enospc_errors); 3774 if (!ret) 3775 ret = -ENOSPC; 3776 } 3777 3778 return ret; 3779 } 3780 3781 /** 3782 * alloc_profile_is_valid - see if a given profile is valid and reduced 3783 * @flags: profile to validate 3784 * @extended: if true @flags is treated as an extended profile 3785 */ 3786 static int alloc_profile_is_valid(u64 flags, int extended) 3787 { 3788 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK : 3789 BTRFS_BLOCK_GROUP_PROFILE_MASK); 3790 3791 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK; 3792 3793 /* 1) check that all other bits are zeroed */ 3794 if (flags & ~mask) 3795 return 0; 3796 3797 /* 2) see if profile is reduced */ 3798 if (flags == 0) 3799 return !extended; /* "0" is valid for usual profiles */ 3800 3801 return has_single_bit_set(flags); 3802 } 3803 3804 static inline int balance_need_close(struct btrfs_fs_info *fs_info) 3805 { 3806 /* cancel requested || normal exit path */ 3807 return atomic_read(&fs_info->balance_cancel_req) || 3808 (atomic_read(&fs_info->balance_pause_req) == 0 && 3809 atomic_read(&fs_info->balance_cancel_req) == 0); 3810 } 3811 3812 /* 3813 * Validate target profile against allowed profiles and return true if it's OK. 3814 * Otherwise print the error message and return false. 3815 */ 3816 static inline int validate_convert_profile(struct btrfs_fs_info *fs_info, 3817 const struct btrfs_balance_args *bargs, 3818 u64 allowed, const char *type) 3819 { 3820 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) 3821 return true; 3822 3823 /* Profile is valid and does not have bits outside of the allowed set */ 3824 if (alloc_profile_is_valid(bargs->target, 1) && 3825 (bargs->target & ~allowed) == 0) 3826 return true; 3827 3828 btrfs_err(fs_info, "balance: invalid convert %s profile %s", 3829 type, btrfs_bg_type_to_raid_name(bargs->target)); 3830 return false; 3831 } 3832 3833 /* 3834 * Fill @buf with textual description of balance filter flags @bargs, up to 3835 * @size_buf including the terminating null. The output may be trimmed if it 3836 * does not fit into the provided buffer. 3837 */ 3838 static void describe_balance_args(struct btrfs_balance_args *bargs, char *buf, 3839 u32 size_buf) 3840 { 3841 int ret; 3842 u32 size_bp = size_buf; 3843 char *bp = buf; 3844 u64 flags = bargs->flags; 3845 char tmp_buf[128] = {'\0'}; 3846 3847 if (!flags) 3848 return; 3849 3850 #define CHECK_APPEND_NOARG(a) \ 3851 do { \ 3852 ret = snprintf(bp, size_bp, (a)); \ 3853 if (ret < 0 || ret >= size_bp) \ 3854 goto out_overflow; \ 3855 size_bp -= ret; \ 3856 bp += ret; \ 3857 } while (0) 3858 3859 #define CHECK_APPEND_1ARG(a, v1) \ 3860 do { \ 3861 ret = snprintf(bp, size_bp, (a), (v1)); \ 3862 if (ret < 0 || ret >= size_bp) \ 3863 goto out_overflow; \ 3864 size_bp -= ret; \ 3865 bp += ret; \ 3866 } while (0) 3867 3868 #define CHECK_APPEND_2ARG(a, v1, v2) \ 3869 do { \ 3870 ret = snprintf(bp, size_bp, (a), (v1), (v2)); \ 3871 if (ret < 0 || ret >= size_bp) \ 3872 goto out_overflow; \ 3873 size_bp -= ret; \ 3874 bp += ret; \ 3875 } while (0) 3876 3877 if (flags & BTRFS_BALANCE_ARGS_CONVERT) 3878 CHECK_APPEND_1ARG("convert=%s,", 3879 btrfs_bg_type_to_raid_name(bargs->target)); 3880 3881 if (flags & BTRFS_BALANCE_ARGS_SOFT) 3882 CHECK_APPEND_NOARG("soft,"); 3883 3884 if (flags & BTRFS_BALANCE_ARGS_PROFILES) { 3885 btrfs_describe_block_groups(bargs->profiles, tmp_buf, 3886 sizeof(tmp_buf)); 3887 CHECK_APPEND_1ARG("profiles=%s,", tmp_buf); 3888 } 3889 3890 if (flags & BTRFS_BALANCE_ARGS_USAGE) 3891 CHECK_APPEND_1ARG("usage=%llu,", bargs->usage); 3892 3893 if (flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) 3894 CHECK_APPEND_2ARG("usage=%u..%u,", 3895 bargs->usage_min, bargs->usage_max); 3896 3897 if (flags & BTRFS_BALANCE_ARGS_DEVID) 3898 CHECK_APPEND_1ARG("devid=%llu,", bargs->devid); 3899 3900 if (flags & BTRFS_BALANCE_ARGS_DRANGE) 3901 CHECK_APPEND_2ARG("drange=%llu..%llu,", 3902 bargs->pstart, bargs->pend); 3903 3904 if (flags & BTRFS_BALANCE_ARGS_VRANGE) 3905 CHECK_APPEND_2ARG("vrange=%llu..%llu,", 3906 bargs->vstart, bargs->vend); 3907 3908 if (flags & BTRFS_BALANCE_ARGS_LIMIT) 3909 CHECK_APPEND_1ARG("limit=%llu,", bargs->limit); 3910 3911 if (flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE) 3912 CHECK_APPEND_2ARG("limit=%u..%u,", 3913 bargs->limit_min, bargs->limit_max); 3914 3915 if (flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) 3916 CHECK_APPEND_2ARG("stripes=%u..%u,", 3917 bargs->stripes_min, bargs->stripes_max); 3918 3919 #undef CHECK_APPEND_2ARG 3920 #undef CHECK_APPEND_1ARG 3921 #undef CHECK_APPEND_NOARG 3922 3923 out_overflow: 3924 3925 if (size_bp < size_buf) 3926 buf[size_buf - size_bp - 1] = '\0'; /* remove last , */ 3927 else 3928 buf[0] = '\0'; 3929 } 3930 3931 static void describe_balance_start_or_resume(struct btrfs_fs_info *fs_info) 3932 { 3933 u32 size_buf = 1024; 3934 char tmp_buf[192] = {'\0'}; 3935 char *buf; 3936 char *bp; 3937 u32 size_bp = size_buf; 3938 int ret; 3939 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 3940 3941 buf = kzalloc(size_buf, GFP_KERNEL); 3942 if (!buf) 3943 return; 3944 3945 bp = buf; 3946 3947 #define CHECK_APPEND_1ARG(a, v1) \ 3948 do { \ 3949 ret = snprintf(bp, size_bp, (a), (v1)); \ 3950 if (ret < 0 || ret >= size_bp) \ 3951 goto out_overflow; \ 3952 size_bp -= ret; \ 3953 bp += ret; \ 3954 } while (0) 3955 3956 if (bctl->flags & BTRFS_BALANCE_FORCE) 3957 CHECK_APPEND_1ARG("%s", "-f "); 3958 3959 if (bctl->flags & BTRFS_BALANCE_DATA) { 3960 describe_balance_args(&bctl->data, tmp_buf, sizeof(tmp_buf)); 3961 CHECK_APPEND_1ARG("-d%s ", tmp_buf); 3962 } 3963 3964 if (bctl->flags & BTRFS_BALANCE_METADATA) { 3965 describe_balance_args(&bctl->meta, tmp_buf, sizeof(tmp_buf)); 3966 CHECK_APPEND_1ARG("-m%s ", tmp_buf); 3967 } 3968 3969 if (bctl->flags & BTRFS_BALANCE_SYSTEM) { 3970 describe_balance_args(&bctl->sys, tmp_buf, sizeof(tmp_buf)); 3971 CHECK_APPEND_1ARG("-s%s ", tmp_buf); 3972 } 3973 3974 #undef CHECK_APPEND_1ARG 3975 3976 out_overflow: 3977 3978 if (size_bp < size_buf) 3979 buf[size_buf - size_bp - 1] = '\0'; /* remove last " " */ 3980 btrfs_info(fs_info, "balance: %s %s", 3981 (bctl->flags & BTRFS_BALANCE_RESUME) ? 3982 "resume" : "start", buf); 3983 3984 kfree(buf); 3985 } 3986 3987 /* 3988 * Should be called with balance mutexe held 3989 */ 3990 int btrfs_balance(struct btrfs_fs_info *fs_info, 3991 struct btrfs_balance_control *bctl, 3992 struct btrfs_ioctl_balance_args *bargs) 3993 { 3994 u64 meta_target, data_target; 3995 u64 allowed; 3996 int mixed = 0; 3997 int ret; 3998 u64 num_devices; 3999 unsigned seq; 4000 bool reducing_redundancy; 4001 int i; 4002 4003 if (btrfs_fs_closing(fs_info) || 4004 atomic_read(&fs_info->balance_pause_req) || 4005 btrfs_should_cancel_balance(fs_info)) { 4006 ret = -EINVAL; 4007 goto out; 4008 } 4009 4010 allowed = btrfs_super_incompat_flags(fs_info->super_copy); 4011 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) 4012 mixed = 1; 4013 4014 /* 4015 * In case of mixed groups both data and meta should be picked, 4016 * and identical options should be given for both of them. 4017 */ 4018 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA; 4019 if (mixed && (bctl->flags & allowed)) { 4020 if (!(bctl->flags & BTRFS_BALANCE_DATA) || 4021 !(bctl->flags & BTRFS_BALANCE_METADATA) || 4022 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { 4023 btrfs_err(fs_info, 4024 "balance: mixed groups data and metadata options must be the same"); 4025 ret = -EINVAL; 4026 goto out; 4027 } 4028 } 4029 4030 /* 4031 * rw_devices will not change at the moment, device add/delete/replace 4032 * are excluded by EXCL_OP 4033 */ 4034 num_devices = fs_info->fs_devices->rw_devices; 4035 4036 /* 4037 * SINGLE profile on-disk has no profile bit, but in-memory we have a 4038 * special bit for it, to make it easier to distinguish. Thus we need 4039 * to set it manually, or balance would refuse the profile. 4040 */ 4041 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; 4042 for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) 4043 if (num_devices >= btrfs_raid_array[i].devs_min) 4044 allowed |= btrfs_raid_array[i].bg_flag; 4045 4046 if (!validate_convert_profile(fs_info, &bctl->data, allowed, "data") || 4047 !validate_convert_profile(fs_info, &bctl->meta, allowed, "metadata") || 4048 !validate_convert_profile(fs_info, &bctl->sys, allowed, "system")) { 4049 ret = -EINVAL; 4050 goto out; 4051 } 4052 4053 /* 4054 * Allow to reduce metadata or system integrity only if force set for 4055 * profiles with redundancy (copies, parity) 4056 */ 4057 allowed = 0; 4058 for (i = 0; i < ARRAY_SIZE(btrfs_raid_array); i++) { 4059 if (btrfs_raid_array[i].ncopies >= 2 || 4060 btrfs_raid_array[i].tolerated_failures >= 1) 4061 allowed |= btrfs_raid_array[i].bg_flag; 4062 } 4063 do { 4064 seq = read_seqbegin(&fs_info->profiles_lock); 4065 4066 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 4067 (fs_info->avail_system_alloc_bits & allowed) && 4068 !(bctl->sys.target & allowed)) || 4069 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 4070 (fs_info->avail_metadata_alloc_bits & allowed) && 4071 !(bctl->meta.target & allowed))) 4072 reducing_redundancy = true; 4073 else 4074 reducing_redundancy = false; 4075 4076 /* if we're not converting, the target field is uninitialized */ 4077 meta_target = (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) ? 4078 bctl->meta.target : fs_info->avail_metadata_alloc_bits; 4079 data_target = (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) ? 4080 bctl->data.target : fs_info->avail_data_alloc_bits; 4081 } while (read_seqretry(&fs_info->profiles_lock, seq)); 4082 4083 if (reducing_redundancy) { 4084 if (bctl->flags & BTRFS_BALANCE_FORCE) { 4085 btrfs_info(fs_info, 4086 "balance: force reducing metadata redundancy"); 4087 } else { 4088 btrfs_err(fs_info, 4089 "balance: reduces metadata redundancy, use --force if you want this"); 4090 ret = -EINVAL; 4091 goto out; 4092 } 4093 } 4094 4095 if (btrfs_get_num_tolerated_disk_barrier_failures(meta_target) < 4096 btrfs_get_num_tolerated_disk_barrier_failures(data_target)) { 4097 btrfs_warn(fs_info, 4098 "balance: metadata profile %s has lower redundancy than data profile %s", 4099 btrfs_bg_type_to_raid_name(meta_target), 4100 btrfs_bg_type_to_raid_name(data_target)); 4101 } 4102 4103 if (fs_info->send_in_progress) { 4104 btrfs_warn_rl(fs_info, 4105 "cannot run balance while send operations are in progress (%d in progress)", 4106 fs_info->send_in_progress); 4107 ret = -EAGAIN; 4108 goto out; 4109 } 4110 4111 ret = insert_balance_item(fs_info, bctl); 4112 if (ret && ret != -EEXIST) 4113 goto out; 4114 4115 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { 4116 BUG_ON(ret == -EEXIST); 4117 BUG_ON(fs_info->balance_ctl); 4118 spin_lock(&fs_info->balance_lock); 4119 fs_info->balance_ctl = bctl; 4120 spin_unlock(&fs_info->balance_lock); 4121 } else { 4122 BUG_ON(ret != -EEXIST); 4123 spin_lock(&fs_info->balance_lock); 4124 update_balance_args(bctl); 4125 spin_unlock(&fs_info->balance_lock); 4126 } 4127 4128 ASSERT(!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); 4129 set_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags); 4130 describe_balance_start_or_resume(fs_info); 4131 mutex_unlock(&fs_info->balance_mutex); 4132 4133 ret = __btrfs_balance(fs_info); 4134 4135 mutex_lock(&fs_info->balance_mutex); 4136 if (ret == -ECANCELED && atomic_read(&fs_info->balance_pause_req)) 4137 btrfs_info(fs_info, "balance: paused"); 4138 else if (ret == -ECANCELED && atomic_read(&fs_info->balance_cancel_req)) 4139 btrfs_info(fs_info, "balance: canceled"); 4140 else 4141 btrfs_info(fs_info, "balance: ended with status: %d", ret); 4142 4143 clear_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags); 4144 4145 if (bargs) { 4146 memset(bargs, 0, sizeof(*bargs)); 4147 btrfs_update_ioctl_balance_args(fs_info, bargs); 4148 } 4149 4150 if ((ret && ret != -ECANCELED && ret != -ENOSPC) || 4151 balance_need_close(fs_info)) { 4152 reset_balance_state(fs_info); 4153 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 4154 } 4155 4156 wake_up(&fs_info->balance_wait_q); 4157 4158 return ret; 4159 out: 4160 if (bctl->flags & BTRFS_BALANCE_RESUME) 4161 reset_balance_state(fs_info); 4162 else 4163 kfree(bctl); 4164 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 4165 4166 return ret; 4167 } 4168 4169 static int balance_kthread(void *data) 4170 { 4171 struct btrfs_fs_info *fs_info = data; 4172 int ret = 0; 4173 4174 mutex_lock(&fs_info->balance_mutex); 4175 if (fs_info->balance_ctl) 4176 ret = btrfs_balance(fs_info, fs_info->balance_ctl, NULL); 4177 mutex_unlock(&fs_info->balance_mutex); 4178 4179 return ret; 4180 } 4181 4182 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info) 4183 { 4184 struct task_struct *tsk; 4185 4186 mutex_lock(&fs_info->balance_mutex); 4187 if (!fs_info->balance_ctl) { 4188 mutex_unlock(&fs_info->balance_mutex); 4189 return 0; 4190 } 4191 mutex_unlock(&fs_info->balance_mutex); 4192 4193 if (btrfs_test_opt(fs_info, SKIP_BALANCE)) { 4194 btrfs_info(fs_info, "balance: resume skipped"); 4195 return 0; 4196 } 4197 4198 /* 4199 * A ro->rw remount sequence should continue with the paused balance 4200 * regardless of who pauses it, system or the user as of now, so set 4201 * the resume flag. 4202 */ 4203 spin_lock(&fs_info->balance_lock); 4204 fs_info->balance_ctl->flags |= BTRFS_BALANCE_RESUME; 4205 spin_unlock(&fs_info->balance_lock); 4206 4207 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance"); 4208 return PTR_ERR_OR_ZERO(tsk); 4209 } 4210 4211 int btrfs_recover_balance(struct btrfs_fs_info *fs_info) 4212 { 4213 struct btrfs_balance_control *bctl; 4214 struct btrfs_balance_item *item; 4215 struct btrfs_disk_balance_args disk_bargs; 4216 struct btrfs_path *path; 4217 struct extent_buffer *leaf; 4218 struct btrfs_key key; 4219 int ret; 4220 4221 path = btrfs_alloc_path(); 4222 if (!path) 4223 return -ENOMEM; 4224 4225 key.objectid = BTRFS_BALANCE_OBJECTID; 4226 key.type = BTRFS_TEMPORARY_ITEM_KEY; 4227 key.offset = 0; 4228 4229 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 4230 if (ret < 0) 4231 goto out; 4232 if (ret > 0) { /* ret = -ENOENT; */ 4233 ret = 0; 4234 goto out; 4235 } 4236 4237 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 4238 if (!bctl) { 4239 ret = -ENOMEM; 4240 goto out; 4241 } 4242 4243 leaf = path->nodes[0]; 4244 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 4245 4246 bctl->flags = btrfs_balance_flags(leaf, item); 4247 bctl->flags |= BTRFS_BALANCE_RESUME; 4248 4249 btrfs_balance_data(leaf, item, &disk_bargs); 4250 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); 4251 btrfs_balance_meta(leaf, item, &disk_bargs); 4252 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); 4253 btrfs_balance_sys(leaf, item, &disk_bargs); 4254 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); 4255 4256 /* 4257 * This should never happen, as the paused balance state is recovered 4258 * during mount without any chance of other exclusive ops to collide. 4259 * 4260 * This gives the exclusive op status to balance and keeps in paused 4261 * state until user intervention (cancel or umount). If the ownership 4262 * cannot be assigned, show a message but do not fail. The balance 4263 * is in a paused state and must have fs_info::balance_ctl properly 4264 * set up. 4265 */ 4266 if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) 4267 btrfs_warn(fs_info, 4268 "balance: cannot set exclusive op status, resume manually"); 4269 4270 mutex_lock(&fs_info->balance_mutex); 4271 BUG_ON(fs_info->balance_ctl); 4272 spin_lock(&fs_info->balance_lock); 4273 fs_info->balance_ctl = bctl; 4274 spin_unlock(&fs_info->balance_lock); 4275 mutex_unlock(&fs_info->balance_mutex); 4276 out: 4277 btrfs_free_path(path); 4278 return ret; 4279 } 4280 4281 int btrfs_pause_balance(struct btrfs_fs_info *fs_info) 4282 { 4283 int ret = 0; 4284 4285 mutex_lock(&fs_info->balance_mutex); 4286 if (!fs_info->balance_ctl) { 4287 mutex_unlock(&fs_info->balance_mutex); 4288 return -ENOTCONN; 4289 } 4290 4291 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { 4292 atomic_inc(&fs_info->balance_pause_req); 4293 mutex_unlock(&fs_info->balance_mutex); 4294 4295 wait_event(fs_info->balance_wait_q, 4296 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); 4297 4298 mutex_lock(&fs_info->balance_mutex); 4299 /* we are good with balance_ctl ripped off from under us */ 4300 BUG_ON(test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); 4301 atomic_dec(&fs_info->balance_pause_req); 4302 } else { 4303 ret = -ENOTCONN; 4304 } 4305 4306 mutex_unlock(&fs_info->balance_mutex); 4307 return ret; 4308 } 4309 4310 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) 4311 { 4312 mutex_lock(&fs_info->balance_mutex); 4313 if (!fs_info->balance_ctl) { 4314 mutex_unlock(&fs_info->balance_mutex); 4315 return -ENOTCONN; 4316 } 4317 4318 /* 4319 * A paused balance with the item stored on disk can be resumed at 4320 * mount time if the mount is read-write. Otherwise it's still paused 4321 * and we must not allow cancelling as it deletes the item. 4322 */ 4323 if (sb_rdonly(fs_info->sb)) { 4324 mutex_unlock(&fs_info->balance_mutex); 4325 return -EROFS; 4326 } 4327 4328 atomic_inc(&fs_info->balance_cancel_req); 4329 /* 4330 * if we are running just wait and return, balance item is 4331 * deleted in btrfs_balance in this case 4332 */ 4333 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { 4334 mutex_unlock(&fs_info->balance_mutex); 4335 wait_event(fs_info->balance_wait_q, 4336 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); 4337 mutex_lock(&fs_info->balance_mutex); 4338 } else { 4339 mutex_unlock(&fs_info->balance_mutex); 4340 /* 4341 * Lock released to allow other waiters to continue, we'll 4342 * reexamine the status again. 4343 */ 4344 mutex_lock(&fs_info->balance_mutex); 4345 4346 if (fs_info->balance_ctl) { 4347 reset_balance_state(fs_info); 4348 clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); 4349 btrfs_info(fs_info, "balance: canceled"); 4350 } 4351 } 4352 4353 BUG_ON(fs_info->balance_ctl || 4354 test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)); 4355 atomic_dec(&fs_info->balance_cancel_req); 4356 mutex_unlock(&fs_info->balance_mutex); 4357 return 0; 4358 } 4359 4360 int btrfs_uuid_scan_kthread(void *data) 4361 { 4362 struct btrfs_fs_info *fs_info = data; 4363 struct btrfs_root *root = fs_info->tree_root; 4364 struct btrfs_key key; 4365 struct btrfs_path *path = NULL; 4366 int ret = 0; 4367 struct extent_buffer *eb; 4368 int slot; 4369 struct btrfs_root_item root_item; 4370 u32 item_size; 4371 struct btrfs_trans_handle *trans = NULL; 4372 bool closing = false; 4373 4374 path = btrfs_alloc_path(); 4375 if (!path) { 4376 ret = -ENOMEM; 4377 goto out; 4378 } 4379 4380 key.objectid = 0; 4381 key.type = BTRFS_ROOT_ITEM_KEY; 4382 key.offset = 0; 4383 4384 while (1) { 4385 if (btrfs_fs_closing(fs_info)) { 4386 closing = true; 4387 break; 4388 } 4389 ret = btrfs_search_forward(root, &key, path, 4390 BTRFS_OLDEST_GENERATION); 4391 if (ret) { 4392 if (ret > 0) 4393 ret = 0; 4394 break; 4395 } 4396 4397 if (key.type != BTRFS_ROOT_ITEM_KEY || 4398 (key.objectid < BTRFS_FIRST_FREE_OBJECTID && 4399 key.objectid != BTRFS_FS_TREE_OBJECTID) || 4400 key.objectid > BTRFS_LAST_FREE_OBJECTID) 4401 goto skip; 4402 4403 eb = path->nodes[0]; 4404 slot = path->slots[0]; 4405 item_size = btrfs_item_size_nr(eb, slot); 4406 if (item_size < sizeof(root_item)) 4407 goto skip; 4408 4409 read_extent_buffer(eb, &root_item, 4410 btrfs_item_ptr_offset(eb, slot), 4411 (int)sizeof(root_item)); 4412 if (btrfs_root_refs(&root_item) == 0) 4413 goto skip; 4414 4415 if (!btrfs_is_empty_uuid(root_item.uuid) || 4416 !btrfs_is_empty_uuid(root_item.received_uuid)) { 4417 if (trans) 4418 goto update_tree; 4419 4420 btrfs_release_path(path); 4421 /* 4422 * 1 - subvol uuid item 4423 * 1 - received_subvol uuid item 4424 */ 4425 trans = btrfs_start_transaction(fs_info->uuid_root, 2); 4426 if (IS_ERR(trans)) { 4427 ret = PTR_ERR(trans); 4428 break; 4429 } 4430 continue; 4431 } else { 4432 goto skip; 4433 } 4434 update_tree: 4435 if (!btrfs_is_empty_uuid(root_item.uuid)) { 4436 ret = btrfs_uuid_tree_add(trans, root_item.uuid, 4437 BTRFS_UUID_KEY_SUBVOL, 4438 key.objectid); 4439 if (ret < 0) { 4440 btrfs_warn(fs_info, "uuid_tree_add failed %d", 4441 ret); 4442 break; 4443 } 4444 } 4445 4446 if (!btrfs_is_empty_uuid(root_item.received_uuid)) { 4447 ret = btrfs_uuid_tree_add(trans, 4448 root_item.received_uuid, 4449 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 4450 key.objectid); 4451 if (ret < 0) { 4452 btrfs_warn(fs_info, "uuid_tree_add failed %d", 4453 ret); 4454 break; 4455 } 4456 } 4457 4458 skip: 4459 if (trans) { 4460 ret = btrfs_end_transaction(trans); 4461 trans = NULL; 4462 if (ret) 4463 break; 4464 } 4465 4466 btrfs_release_path(path); 4467 if (key.offset < (u64)-1) { 4468 key.offset++; 4469 } else if (key.type < BTRFS_ROOT_ITEM_KEY) { 4470 key.offset = 0; 4471 key.type = BTRFS_ROOT_ITEM_KEY; 4472 } else if (key.objectid < (u64)-1) { 4473 key.offset = 0; 4474 key.type = BTRFS_ROOT_ITEM_KEY; 4475 key.objectid++; 4476 } else { 4477 break; 4478 } 4479 cond_resched(); 4480 } 4481 4482 out: 4483 btrfs_free_path(path); 4484 if (trans && !IS_ERR(trans)) 4485 btrfs_end_transaction(trans); 4486 if (ret) 4487 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret); 4488 else if (!closing) 4489 set_bit(BTRFS_FS_UPDATE_UUID_TREE_GEN, &fs_info->flags); 4490 up(&fs_info->uuid_tree_rescan_sem); 4491 return 0; 4492 } 4493 4494 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info) 4495 { 4496 struct btrfs_trans_handle *trans; 4497 struct btrfs_root *tree_root = fs_info->tree_root; 4498 struct btrfs_root *uuid_root; 4499 struct task_struct *task; 4500 int ret; 4501 4502 /* 4503 * 1 - root node 4504 * 1 - root item 4505 */ 4506 trans = btrfs_start_transaction(tree_root, 2); 4507 if (IS_ERR(trans)) 4508 return PTR_ERR(trans); 4509 4510 uuid_root = btrfs_create_tree(trans, BTRFS_UUID_TREE_OBJECTID); 4511 if (IS_ERR(uuid_root)) { 4512 ret = PTR_ERR(uuid_root); 4513 btrfs_abort_transaction(trans, ret); 4514 btrfs_end_transaction(trans); 4515 return ret; 4516 } 4517 4518 fs_info->uuid_root = uuid_root; 4519 4520 ret = btrfs_commit_transaction(trans); 4521 if (ret) 4522 return ret; 4523 4524 down(&fs_info->uuid_tree_rescan_sem); 4525 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid"); 4526 if (IS_ERR(task)) { 4527 /* fs_info->update_uuid_tree_gen remains 0 in all error case */ 4528 btrfs_warn(fs_info, "failed to start uuid_scan task"); 4529 up(&fs_info->uuid_tree_rescan_sem); 4530 return PTR_ERR(task); 4531 } 4532 4533 return 0; 4534 } 4535 4536 /* 4537 * shrinking a device means finding all of the device extents past 4538 * the new size, and then following the back refs to the chunks. 4539 * The chunk relocation code actually frees the device extent 4540 */ 4541 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 4542 { 4543 struct btrfs_fs_info *fs_info = device->fs_info; 4544 struct btrfs_root *root = fs_info->dev_root; 4545 struct btrfs_trans_handle *trans; 4546 struct btrfs_dev_extent *dev_extent = NULL; 4547 struct btrfs_path *path; 4548 u64 length; 4549 u64 chunk_offset; 4550 int ret; 4551 int slot; 4552 int failed = 0; 4553 bool retried = false; 4554 struct extent_buffer *l; 4555 struct btrfs_key key; 4556 struct btrfs_super_block *super_copy = fs_info->super_copy; 4557 u64 old_total = btrfs_super_total_bytes(super_copy); 4558 u64 old_size = btrfs_device_get_total_bytes(device); 4559 u64 diff; 4560 u64 start; 4561 4562 new_size = round_down(new_size, fs_info->sectorsize); 4563 start = new_size; 4564 diff = round_down(old_size - new_size, fs_info->sectorsize); 4565 4566 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) 4567 return -EINVAL; 4568 4569 path = btrfs_alloc_path(); 4570 if (!path) 4571 return -ENOMEM; 4572 4573 path->reada = READA_BACK; 4574 4575 trans = btrfs_start_transaction(root, 0); 4576 if (IS_ERR(trans)) { 4577 btrfs_free_path(path); 4578 return PTR_ERR(trans); 4579 } 4580 4581 mutex_lock(&fs_info->chunk_mutex); 4582 4583 btrfs_device_set_total_bytes(device, new_size); 4584 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { 4585 device->fs_devices->total_rw_bytes -= diff; 4586 atomic64_sub(diff, &fs_info->free_chunk_space); 4587 } 4588 4589 /* 4590 * Once the device's size has been set to the new size, ensure all 4591 * in-memory chunks are synced to disk so that the loop below sees them 4592 * and relocates them accordingly. 4593 */ 4594 if (contains_pending_extent(device, &start, diff)) { 4595 mutex_unlock(&fs_info->chunk_mutex); 4596 ret = btrfs_commit_transaction(trans); 4597 if (ret) 4598 goto done; 4599 } else { 4600 mutex_unlock(&fs_info->chunk_mutex); 4601 btrfs_end_transaction(trans); 4602 } 4603 4604 again: 4605 key.objectid = device->devid; 4606 key.offset = (u64)-1; 4607 key.type = BTRFS_DEV_EXTENT_KEY; 4608 4609 do { 4610 mutex_lock(&fs_info->delete_unused_bgs_mutex); 4611 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 4612 if (ret < 0) { 4613 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 4614 goto done; 4615 } 4616 4617 ret = btrfs_previous_item(root, path, 0, key.type); 4618 if (ret) 4619 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 4620 if (ret < 0) 4621 goto done; 4622 if (ret) { 4623 ret = 0; 4624 btrfs_release_path(path); 4625 break; 4626 } 4627 4628 l = path->nodes[0]; 4629 slot = path->slots[0]; 4630 btrfs_item_key_to_cpu(l, &key, path->slots[0]); 4631 4632 if (key.objectid != device->devid) { 4633 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 4634 btrfs_release_path(path); 4635 break; 4636 } 4637 4638 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 4639 length = btrfs_dev_extent_length(l, dev_extent); 4640 4641 if (key.offset + length <= new_size) { 4642 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 4643 btrfs_release_path(path); 4644 break; 4645 } 4646 4647 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); 4648 btrfs_release_path(path); 4649 4650 /* 4651 * We may be relocating the only data chunk we have, 4652 * which could potentially end up with losing data's 4653 * raid profile, so lets allocate an empty one in 4654 * advance. 4655 */ 4656 ret = btrfs_may_alloc_data_chunk(fs_info, chunk_offset); 4657 if (ret < 0) { 4658 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 4659 goto done; 4660 } 4661 4662 ret = btrfs_relocate_chunk(fs_info, chunk_offset); 4663 mutex_unlock(&fs_info->delete_unused_bgs_mutex); 4664 if (ret == -ENOSPC) { 4665 failed++; 4666 } else if (ret) { 4667 if (ret == -ETXTBSY) { 4668 btrfs_warn(fs_info, 4669 "could not shrink block group %llu due to active swapfile", 4670 chunk_offset); 4671 } 4672 goto done; 4673 } 4674 } while (key.offset-- > 0); 4675 4676 if (failed && !retried) { 4677 failed = 0; 4678 retried = true; 4679 goto again; 4680 } else if (failed && retried) { 4681 ret = -ENOSPC; 4682 goto done; 4683 } 4684 4685 /* Shrinking succeeded, else we would be at "done". */ 4686 trans = btrfs_start_transaction(root, 0); 4687 if (IS_ERR(trans)) { 4688 ret = PTR_ERR(trans); 4689 goto done; 4690 } 4691 4692 mutex_lock(&fs_info->chunk_mutex); 4693 btrfs_device_set_disk_total_bytes(device, new_size); 4694 if (list_empty(&device->post_commit_list)) 4695 list_add_tail(&device->post_commit_list, 4696 &trans->transaction->dev_update_list); 4697 4698 WARN_ON(diff > old_total); 4699 btrfs_set_super_total_bytes(super_copy, 4700 round_down(old_total - diff, fs_info->sectorsize)); 4701 mutex_unlock(&fs_info->chunk_mutex); 4702 4703 /* Now btrfs_update_device() will change the on-disk size. */ 4704 ret = btrfs_update_device(trans, device); 4705 if (ret < 0) { 4706 btrfs_abort_transaction(trans, ret); 4707 btrfs_end_transaction(trans); 4708 } else { 4709 ret = btrfs_commit_transaction(trans); 4710 } 4711 done: 4712 btrfs_free_path(path); 4713 if (ret) { 4714 mutex_lock(&fs_info->chunk_mutex); 4715 btrfs_device_set_total_bytes(device, old_size); 4716 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) 4717 device->fs_devices->total_rw_bytes += diff; 4718 atomic64_add(diff, &fs_info->free_chunk_space); 4719 mutex_unlock(&fs_info->chunk_mutex); 4720 } 4721 return ret; 4722 } 4723 4724 static int btrfs_add_system_chunk(struct btrfs_fs_info *fs_info, 4725 struct btrfs_key *key, 4726 struct btrfs_chunk *chunk, int item_size) 4727 { 4728 struct btrfs_super_block *super_copy = fs_info->super_copy; 4729 struct btrfs_disk_key disk_key; 4730 u32 array_size; 4731 u8 *ptr; 4732 4733 mutex_lock(&fs_info->chunk_mutex); 4734 array_size = btrfs_super_sys_array_size(super_copy); 4735 if (array_size + item_size + sizeof(disk_key) 4736 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) { 4737 mutex_unlock(&fs_info->chunk_mutex); 4738 return -EFBIG; 4739 } 4740 4741 ptr = super_copy->sys_chunk_array + array_size; 4742 btrfs_cpu_key_to_disk(&disk_key, key); 4743 memcpy(ptr, &disk_key, sizeof(disk_key)); 4744 ptr += sizeof(disk_key); 4745 memcpy(ptr, chunk, item_size); 4746 item_size += sizeof(disk_key); 4747 btrfs_set_super_sys_array_size(super_copy, array_size + item_size); 4748 mutex_unlock(&fs_info->chunk_mutex); 4749 4750 return 0; 4751 } 4752 4753 /* 4754 * sort the devices in descending order by max_avail, total_avail 4755 */ 4756 static int btrfs_cmp_device_info(const void *a, const void *b) 4757 { 4758 const struct btrfs_device_info *di_a = a; 4759 const struct btrfs_device_info *di_b = b; 4760 4761 if (di_a->max_avail > di_b->max_avail) 4762 return -1; 4763 if (di_a->max_avail < di_b->max_avail) 4764 return 1; 4765 if (di_a->total_avail > di_b->total_avail) 4766 return -1; 4767 if (di_a->total_avail < di_b->total_avail) 4768 return 1; 4769 return 0; 4770 } 4771 4772 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type) 4773 { 4774 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK)) 4775 return; 4776 4777 btrfs_set_fs_incompat(info, RAID56); 4778 } 4779 4780 static void check_raid1c34_incompat_flag(struct btrfs_fs_info *info, u64 type) 4781 { 4782 if (!(type & (BTRFS_BLOCK_GROUP_RAID1C3 | BTRFS_BLOCK_GROUP_RAID1C4))) 4783 return; 4784 4785 btrfs_set_fs_incompat(info, RAID1C34); 4786 } 4787 4788 /* 4789 * Structure used internally for __btrfs_alloc_chunk() function. 4790 * Wraps needed parameters. 4791 */ 4792 struct alloc_chunk_ctl { 4793 u64 start; 4794 u64 type; 4795 /* Total number of stripes to allocate */ 4796 int num_stripes; 4797 /* sub_stripes info for map */ 4798 int sub_stripes; 4799 /* Stripes per device */ 4800 int dev_stripes; 4801 /* Maximum number of devices to use */ 4802 int devs_max; 4803 /* Minimum number of devices to use */ 4804 int devs_min; 4805 /* ndevs has to be a multiple of this */ 4806 int devs_increment; 4807 /* Number of copies */ 4808 int ncopies; 4809 /* Number of stripes worth of bytes to store parity information */ 4810 int nparity; 4811 u64 max_stripe_size; 4812 u64 max_chunk_size; 4813 u64 dev_extent_min; 4814 u64 stripe_size; 4815 u64 chunk_size; 4816 int ndevs; 4817 }; 4818 4819 static void init_alloc_chunk_ctl_policy_regular( 4820 struct btrfs_fs_devices *fs_devices, 4821 struct alloc_chunk_ctl *ctl) 4822 { 4823 u64 type = ctl->type; 4824 4825 if (type & BTRFS_BLOCK_GROUP_DATA) { 4826 ctl->max_stripe_size = SZ_1G; 4827 ctl->max_chunk_size = BTRFS_MAX_DATA_CHUNK_SIZE; 4828 } else if (type & BTRFS_BLOCK_GROUP_METADATA) { 4829 /* For larger filesystems, use larger metadata chunks */ 4830 if (fs_devices->total_rw_bytes > 50ULL * SZ_1G) 4831 ctl->max_stripe_size = SZ_1G; 4832 else 4833 ctl->max_stripe_size = SZ_256M; 4834 ctl->max_chunk_size = ctl->max_stripe_size; 4835 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { 4836 ctl->max_stripe_size = SZ_32M; 4837 ctl->max_chunk_size = 2 * ctl->max_stripe_size; 4838 ctl->devs_max = min_t(int, ctl->devs_max, 4839 BTRFS_MAX_DEVS_SYS_CHUNK); 4840 } else { 4841 BUG(); 4842 } 4843 4844 /* We don't want a chunk larger than 10% of writable space */ 4845 ctl->max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1), 4846 ctl->max_chunk_size); 4847 ctl->dev_extent_min = BTRFS_STRIPE_LEN * ctl->dev_stripes; 4848 } 4849 4850 static void init_alloc_chunk_ctl(struct btrfs_fs_devices *fs_devices, 4851 struct alloc_chunk_ctl *ctl) 4852 { 4853 int index = btrfs_bg_flags_to_raid_index(ctl->type); 4854 4855 ctl->sub_stripes = btrfs_raid_array[index].sub_stripes; 4856 ctl->dev_stripes = btrfs_raid_array[index].dev_stripes; 4857 ctl->devs_max = btrfs_raid_array[index].devs_max; 4858 if (!ctl->devs_max) 4859 ctl->devs_max = BTRFS_MAX_DEVS(fs_devices->fs_info); 4860 ctl->devs_min = btrfs_raid_array[index].devs_min; 4861 ctl->devs_increment = btrfs_raid_array[index].devs_increment; 4862 ctl->ncopies = btrfs_raid_array[index].ncopies; 4863 ctl->nparity = btrfs_raid_array[index].nparity; 4864 ctl->ndevs = 0; 4865 4866 switch (fs_devices->chunk_alloc_policy) { 4867 case BTRFS_CHUNK_ALLOC_REGULAR: 4868 init_alloc_chunk_ctl_policy_regular(fs_devices, ctl); 4869 break; 4870 default: 4871 BUG(); 4872 } 4873 } 4874 4875 static int gather_device_info(struct btrfs_fs_devices *fs_devices, 4876 struct alloc_chunk_ctl *ctl, 4877 struct btrfs_device_info *devices_info) 4878 { 4879 struct btrfs_fs_info *info = fs_devices->fs_info; 4880 struct btrfs_device *device; 4881 u64 total_avail; 4882 u64 dev_extent_want = ctl->max_stripe_size * ctl->dev_stripes; 4883 int ret; 4884 int ndevs = 0; 4885 u64 max_avail; 4886 u64 dev_offset; 4887 4888 /* 4889 * in the first pass through the devices list, we gather information 4890 * about the available holes on each device. 4891 */ 4892 list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) { 4893 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { 4894 WARN(1, KERN_ERR 4895 "BTRFS: read-only device in alloc_list\n"); 4896 continue; 4897 } 4898 4899 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, 4900 &device->dev_state) || 4901 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) 4902 continue; 4903 4904 if (device->total_bytes > device->bytes_used) 4905 total_avail = device->total_bytes - device->bytes_used; 4906 else 4907 total_avail = 0; 4908 4909 /* If there is no space on this device, skip it. */ 4910 if (total_avail < ctl->dev_extent_min) 4911 continue; 4912 4913 ret = find_free_dev_extent(device, dev_extent_want, &dev_offset, 4914 &max_avail); 4915 if (ret && ret != -ENOSPC) 4916 return ret; 4917 4918 if (ret == 0) 4919 max_avail = dev_extent_want; 4920 4921 if (max_avail < ctl->dev_extent_min) { 4922 if (btrfs_test_opt(info, ENOSPC_DEBUG)) 4923 btrfs_debug(info, 4924 "%s: devid %llu has no free space, have=%llu want=%llu", 4925 __func__, device->devid, max_avail, 4926 ctl->dev_extent_min); 4927 continue; 4928 } 4929 4930 if (ndevs == fs_devices->rw_devices) { 4931 WARN(1, "%s: found more than %llu devices\n", 4932 __func__, fs_devices->rw_devices); 4933 break; 4934 } 4935 devices_info[ndevs].dev_offset = dev_offset; 4936 devices_info[ndevs].max_avail = max_avail; 4937 devices_info[ndevs].total_avail = total_avail; 4938 devices_info[ndevs].dev = device; 4939 ++ndevs; 4940 } 4941 ctl->ndevs = ndevs; 4942 4943 /* 4944 * now sort the devices by hole size / available space 4945 */ 4946 sort(devices_info, ndevs, sizeof(struct btrfs_device_info), 4947 btrfs_cmp_device_info, NULL); 4948 4949 return 0; 4950 } 4951 4952 static int decide_stripe_size_regular(struct alloc_chunk_ctl *ctl, 4953 struct btrfs_device_info *devices_info) 4954 { 4955 /* Number of stripes that count for block group size */ 4956 int data_stripes; 4957 4958 /* 4959 * The primary goal is to maximize the number of stripes, so use as 4960 * many devices as possible, even if the stripes are not maximum sized. 4961 * 4962 * The DUP profile stores more than one stripe per device, the 4963 * max_avail is the total size so we have to adjust. 4964 */ 4965 ctl->stripe_size = div_u64(devices_info[ctl->ndevs - 1].max_avail, 4966 ctl->dev_stripes); 4967 ctl->num_stripes = ctl->ndevs * ctl->dev_stripes; 4968 4969 /* This will have to be fixed for RAID1 and RAID10 over more drives */ 4970 data_stripes = (ctl->num_stripes - ctl->nparity) / ctl->ncopies; 4971 4972 /* 4973 * Use the number of data stripes to figure out how big this chunk is 4974 * really going to be in terms of logical address space, and compare 4975 * that answer with the max chunk size. If it's higher, we try to 4976 * reduce stripe_size. 4977 */ 4978 if (ctl->stripe_size * data_stripes > ctl->max_chunk_size) { 4979 /* 4980 * Reduce stripe_size, round it up to a 16MB boundary again and 4981 * then use it, unless it ends up being even bigger than the 4982 * previous value we had already. 4983 */ 4984 ctl->stripe_size = min(round_up(div_u64(ctl->max_chunk_size, 4985 data_stripes), SZ_16M), 4986 ctl->stripe_size); 4987 } 4988 4989 /* Align to BTRFS_STRIPE_LEN */ 4990 ctl->stripe_size = round_down(ctl->stripe_size, BTRFS_STRIPE_LEN); 4991 ctl->chunk_size = ctl->stripe_size * data_stripes; 4992 4993 return 0; 4994 } 4995 4996 static int decide_stripe_size(struct btrfs_fs_devices *fs_devices, 4997 struct alloc_chunk_ctl *ctl, 4998 struct btrfs_device_info *devices_info) 4999 { 5000 struct btrfs_fs_info *info = fs_devices->fs_info; 5001 5002 /* 5003 * Round down to number of usable stripes, devs_increment can be any 5004 * number so we can't use round_down() that requires power of 2, while 5005 * rounddown is safe. 5006 */ 5007 ctl->ndevs = rounddown(ctl->ndevs, ctl->devs_increment); 5008 5009 if (ctl->ndevs < ctl->devs_min) { 5010 if (btrfs_test_opt(info, ENOSPC_DEBUG)) { 5011 btrfs_debug(info, 5012 "%s: not enough devices with free space: have=%d minimum required=%d", 5013 __func__, ctl->ndevs, ctl->devs_min); 5014 } 5015 return -ENOSPC; 5016 } 5017 5018 ctl->ndevs = min(ctl->ndevs, ctl->devs_max); 5019 5020 switch (fs_devices->chunk_alloc_policy) { 5021 case BTRFS_CHUNK_ALLOC_REGULAR: 5022 return decide_stripe_size_regular(ctl, devices_info); 5023 default: 5024 BUG(); 5025 } 5026 } 5027 5028 static int create_chunk(struct btrfs_trans_handle *trans, 5029 struct alloc_chunk_ctl *ctl, 5030 struct btrfs_device_info *devices_info) 5031 { 5032 struct btrfs_fs_info *info = trans->fs_info; 5033 struct map_lookup *map = NULL; 5034 struct extent_map_tree *em_tree; 5035 struct extent_map *em; 5036 u64 start = ctl->start; 5037 u64 type = ctl->type; 5038 int ret; 5039 int i; 5040 int j; 5041 5042 map = kmalloc(map_lookup_size(ctl->num_stripes), GFP_NOFS); 5043 if (!map) 5044 return -ENOMEM; 5045 map->num_stripes = ctl->num_stripes; 5046 5047 for (i = 0; i < ctl->ndevs; ++i) { 5048 for (j = 0; j < ctl->dev_stripes; ++j) { 5049 int s = i * ctl->dev_stripes + j; 5050 map->stripes[s].dev = devices_info[i].dev; 5051 map->stripes[s].physical = devices_info[i].dev_offset + 5052 j * ctl->stripe_size; 5053 } 5054 } 5055 map->stripe_len = BTRFS_STRIPE_LEN; 5056 map->io_align = BTRFS_STRIPE_LEN; 5057 map->io_width = BTRFS_STRIPE_LEN; 5058 map->type = type; 5059 map->sub_stripes = ctl->sub_stripes; 5060 5061 trace_btrfs_chunk_alloc(info, map, start, ctl->chunk_size); 5062 5063 em = alloc_extent_map(); 5064 if (!em) { 5065 kfree(map); 5066 return -ENOMEM; 5067 } 5068 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags); 5069 em->map_lookup = map; 5070 em->start = start; 5071 em->len = ctl->chunk_size; 5072 em->block_start = 0; 5073 em->block_len = em->len; 5074 em->orig_block_len = ctl->stripe_size; 5075 5076 em_tree = &info->mapping_tree; 5077 write_lock(&em_tree->lock); 5078 ret = add_extent_mapping(em_tree, em, 0); 5079 if (ret) { 5080 write_unlock(&em_tree->lock); 5081 free_extent_map(em); 5082 return ret; 5083 } 5084 write_unlock(&em_tree->lock); 5085 5086 ret = btrfs_make_block_group(trans, 0, type, start, ctl->chunk_size); 5087 if (ret) 5088 goto error_del_extent; 5089 5090 for (i = 0; i < map->num_stripes; i++) { 5091 struct btrfs_device *dev = map->stripes[i].dev; 5092 5093 btrfs_device_set_bytes_used(dev, 5094 dev->bytes_used + ctl->stripe_size); 5095 if (list_empty(&dev->post_commit_list)) 5096 list_add_tail(&dev->post_commit_list, 5097 &trans->transaction->dev_update_list); 5098 } 5099 5100 atomic64_sub(ctl->stripe_size * map->num_stripes, 5101 &info->free_chunk_space); 5102 5103 free_extent_map(em); 5104 check_raid56_incompat_flag(info, type); 5105 check_raid1c34_incompat_flag(info, type); 5106 5107 return 0; 5108 5109 error_del_extent: 5110 write_lock(&em_tree->lock); 5111 remove_extent_mapping(em_tree, em); 5112 write_unlock(&em_tree->lock); 5113 5114 /* One for our allocation */ 5115 free_extent_map(em); 5116 /* One for the tree reference */ 5117 free_extent_map(em); 5118 5119 return ret; 5120 } 5121 5122 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type) 5123 { 5124 struct btrfs_fs_info *info = trans->fs_info; 5125 struct btrfs_fs_devices *fs_devices = info->fs_devices; 5126 struct btrfs_device_info *devices_info = NULL; 5127 struct alloc_chunk_ctl ctl; 5128 int ret; 5129 5130 lockdep_assert_held(&info->chunk_mutex); 5131 5132 if (!alloc_profile_is_valid(type, 0)) { 5133 ASSERT(0); 5134 return -EINVAL; 5135 } 5136 5137 if (list_empty(&fs_devices->alloc_list)) { 5138 if (btrfs_test_opt(info, ENOSPC_DEBUG)) 5139 btrfs_debug(info, "%s: no writable device", __func__); 5140 return -ENOSPC; 5141 } 5142 5143 if (!(type & BTRFS_BLOCK_GROUP_TYPE_MASK)) { 5144 btrfs_err(info, "invalid chunk type 0x%llx requested", type); 5145 ASSERT(0); 5146 return -EINVAL; 5147 } 5148 5149 ctl.start = find_next_chunk(info); 5150 ctl.type = type; 5151 init_alloc_chunk_ctl(fs_devices, &ctl); 5152 5153 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info), 5154 GFP_NOFS); 5155 if (!devices_info) 5156 return -ENOMEM; 5157 5158 ret = gather_device_info(fs_devices, &ctl, devices_info); 5159 if (ret < 0) 5160 goto out; 5161 5162 ret = decide_stripe_size(fs_devices, &ctl, devices_info); 5163 if (ret < 0) 5164 goto out; 5165 5166 ret = create_chunk(trans, &ctl, devices_info); 5167 5168 out: 5169 kfree(devices_info); 5170 return ret; 5171 } 5172 5173 /* 5174 * Chunk allocation falls into two parts. The first part does work 5175 * that makes the new allocated chunk usable, but does not do any operation 5176 * that modifies the chunk tree. The second part does the work that 5177 * requires modifying the chunk tree. This division is important for the 5178 * bootstrap process of adding storage to a seed btrfs. 5179 */ 5180 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans, 5181 u64 chunk_offset, u64 chunk_size) 5182 { 5183 struct btrfs_fs_info *fs_info = trans->fs_info; 5184 struct btrfs_root *extent_root = fs_info->extent_root; 5185 struct btrfs_root *chunk_root = fs_info->chunk_root; 5186 struct btrfs_key key; 5187 struct btrfs_device *device; 5188 struct btrfs_chunk *chunk; 5189 struct btrfs_stripe *stripe; 5190 struct extent_map *em; 5191 struct map_lookup *map; 5192 size_t item_size; 5193 u64 dev_offset; 5194 u64 stripe_size; 5195 int i = 0; 5196 int ret = 0; 5197 5198 em = btrfs_get_chunk_map(fs_info, chunk_offset, chunk_size); 5199 if (IS_ERR(em)) 5200 return PTR_ERR(em); 5201 5202 map = em->map_lookup; 5203 item_size = btrfs_chunk_item_size(map->num_stripes); 5204 stripe_size = em->orig_block_len; 5205 5206 chunk = kzalloc(item_size, GFP_NOFS); 5207 if (!chunk) { 5208 ret = -ENOMEM; 5209 goto out; 5210 } 5211 5212 /* 5213 * Take the device list mutex to prevent races with the final phase of 5214 * a device replace operation that replaces the device object associated 5215 * with the map's stripes, because the device object's id can change 5216 * at any time during that final phase of the device replace operation 5217 * (dev-replace.c:btrfs_dev_replace_finishing()). 5218 */ 5219 mutex_lock(&fs_info->fs_devices->device_list_mutex); 5220 for (i = 0; i < map->num_stripes; i++) { 5221 device = map->stripes[i].dev; 5222 dev_offset = map->stripes[i].physical; 5223 5224 ret = btrfs_update_device(trans, device); 5225 if (ret) 5226 break; 5227 ret = btrfs_alloc_dev_extent(trans, device, chunk_offset, 5228 dev_offset, stripe_size); 5229 if (ret) 5230 break; 5231 } 5232 if (ret) { 5233 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 5234 goto out; 5235 } 5236 5237 stripe = &chunk->stripe; 5238 for (i = 0; i < map->num_stripes; i++) { 5239 device = map->stripes[i].dev; 5240 dev_offset = map->stripes[i].physical; 5241 5242 btrfs_set_stack_stripe_devid(stripe, device->devid); 5243 btrfs_set_stack_stripe_offset(stripe, dev_offset); 5244 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); 5245 stripe++; 5246 } 5247 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 5248 5249 btrfs_set_stack_chunk_length(chunk, chunk_size); 5250 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); 5251 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); 5252 btrfs_set_stack_chunk_type(chunk, map->type); 5253 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); 5254 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); 5255 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); 5256 btrfs_set_stack_chunk_sector_size(chunk, fs_info->sectorsize); 5257 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); 5258 5259 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 5260 key.type = BTRFS_CHUNK_ITEM_KEY; 5261 key.offset = chunk_offset; 5262 5263 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); 5264 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 5265 /* 5266 * TODO: Cleanup of inserted chunk root in case of 5267 * failure. 5268 */ 5269 ret = btrfs_add_system_chunk(fs_info, &key, chunk, item_size); 5270 } 5271 5272 out: 5273 kfree(chunk); 5274 free_extent_map(em); 5275 return ret; 5276 } 5277 5278 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans) 5279 { 5280 struct btrfs_fs_info *fs_info = trans->fs_info; 5281 u64 alloc_profile; 5282 int ret; 5283 5284 alloc_profile = btrfs_metadata_alloc_profile(fs_info); 5285 ret = btrfs_alloc_chunk(trans, alloc_profile); 5286 if (ret) 5287 return ret; 5288 5289 alloc_profile = btrfs_system_alloc_profile(fs_info); 5290 ret = btrfs_alloc_chunk(trans, alloc_profile); 5291 return ret; 5292 } 5293 5294 static inline int btrfs_chunk_max_errors(struct map_lookup *map) 5295 { 5296 const int index = btrfs_bg_flags_to_raid_index(map->type); 5297 5298 return btrfs_raid_array[index].tolerated_failures; 5299 } 5300 5301 int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset) 5302 { 5303 struct extent_map *em; 5304 struct map_lookup *map; 5305 int readonly = 0; 5306 int miss_ndevs = 0; 5307 int i; 5308 5309 em = btrfs_get_chunk_map(fs_info, chunk_offset, 1); 5310 if (IS_ERR(em)) 5311 return 1; 5312 5313 map = em->map_lookup; 5314 for (i = 0; i < map->num_stripes; i++) { 5315 if (test_bit(BTRFS_DEV_STATE_MISSING, 5316 &map->stripes[i].dev->dev_state)) { 5317 miss_ndevs++; 5318 continue; 5319 } 5320 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, 5321 &map->stripes[i].dev->dev_state)) { 5322 readonly = 1; 5323 goto end; 5324 } 5325 } 5326 5327 /* 5328 * If the number of missing devices is larger than max errors, 5329 * we can not write the data into that chunk successfully, so 5330 * set it readonly. 5331 */ 5332 if (miss_ndevs > btrfs_chunk_max_errors(map)) 5333 readonly = 1; 5334 end: 5335 free_extent_map(em); 5336 return readonly; 5337 } 5338 5339 void btrfs_mapping_tree_free(struct extent_map_tree *tree) 5340 { 5341 struct extent_map *em; 5342 5343 while (1) { 5344 write_lock(&tree->lock); 5345 em = lookup_extent_mapping(tree, 0, (u64)-1); 5346 if (em) 5347 remove_extent_mapping(tree, em); 5348 write_unlock(&tree->lock); 5349 if (!em) 5350 break; 5351 /* once for us */ 5352 free_extent_map(em); 5353 /* once for the tree */ 5354 free_extent_map(em); 5355 } 5356 } 5357 5358 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) 5359 { 5360 struct extent_map *em; 5361 struct map_lookup *map; 5362 int ret; 5363 5364 em = btrfs_get_chunk_map(fs_info, logical, len); 5365 if (IS_ERR(em)) 5366 /* 5367 * We could return errors for these cases, but that could get 5368 * ugly and we'd probably do the same thing which is just not do 5369 * anything else and exit, so return 1 so the callers don't try 5370 * to use other copies. 5371 */ 5372 return 1; 5373 5374 map = em->map_lookup; 5375 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1_MASK)) 5376 ret = map->num_stripes; 5377 else if (map->type & BTRFS_BLOCK_GROUP_RAID10) 5378 ret = map->sub_stripes; 5379 else if (map->type & BTRFS_BLOCK_GROUP_RAID5) 5380 ret = 2; 5381 else if (map->type & BTRFS_BLOCK_GROUP_RAID6) 5382 /* 5383 * There could be two corrupted data stripes, we need 5384 * to loop retry in order to rebuild the correct data. 5385 * 5386 * Fail a stripe at a time on every retry except the 5387 * stripe under reconstruction. 5388 */ 5389 ret = map->num_stripes; 5390 else 5391 ret = 1; 5392 free_extent_map(em); 5393 5394 down_read(&fs_info->dev_replace.rwsem); 5395 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace) && 5396 fs_info->dev_replace.tgtdev) 5397 ret++; 5398 up_read(&fs_info->dev_replace.rwsem); 5399 5400 return ret; 5401 } 5402 5403 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info, 5404 u64 logical) 5405 { 5406 struct extent_map *em; 5407 struct map_lookup *map; 5408 unsigned long len = fs_info->sectorsize; 5409 5410 em = btrfs_get_chunk_map(fs_info, logical, len); 5411 5412 if (!WARN_ON(IS_ERR(em))) { 5413 map = em->map_lookup; 5414 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) 5415 len = map->stripe_len * nr_data_stripes(map); 5416 free_extent_map(em); 5417 } 5418 return len; 5419 } 5420 5421 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info, u64 logical, u64 len) 5422 { 5423 struct extent_map *em; 5424 struct map_lookup *map; 5425 int ret = 0; 5426 5427 em = btrfs_get_chunk_map(fs_info, logical, len); 5428 5429 if(!WARN_ON(IS_ERR(em))) { 5430 map = em->map_lookup; 5431 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) 5432 ret = 1; 5433 free_extent_map(em); 5434 } 5435 return ret; 5436 } 5437 5438 static int find_live_mirror(struct btrfs_fs_info *fs_info, 5439 struct map_lookup *map, int first, 5440 int dev_replace_is_ongoing) 5441 { 5442 int i; 5443 int num_stripes; 5444 int preferred_mirror; 5445 int tolerance; 5446 struct btrfs_device *srcdev; 5447 5448 ASSERT((map->type & 5449 (BTRFS_BLOCK_GROUP_RAID1_MASK | BTRFS_BLOCK_GROUP_RAID10))); 5450 5451 if (map->type & BTRFS_BLOCK_GROUP_RAID10) 5452 num_stripes = map->sub_stripes; 5453 else 5454 num_stripes = map->num_stripes; 5455 5456 preferred_mirror = first + current->pid % num_stripes; 5457 5458 if (dev_replace_is_ongoing && 5459 fs_info->dev_replace.cont_reading_from_srcdev_mode == 5460 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID) 5461 srcdev = fs_info->dev_replace.srcdev; 5462 else 5463 srcdev = NULL; 5464 5465 /* 5466 * try to avoid the drive that is the source drive for a 5467 * dev-replace procedure, only choose it if no other non-missing 5468 * mirror is available 5469 */ 5470 for (tolerance = 0; tolerance < 2; tolerance++) { 5471 if (map->stripes[preferred_mirror].dev->bdev && 5472 (tolerance || map->stripes[preferred_mirror].dev != srcdev)) 5473 return preferred_mirror; 5474 for (i = first; i < first + num_stripes; i++) { 5475 if (map->stripes[i].dev->bdev && 5476 (tolerance || map->stripes[i].dev != srcdev)) 5477 return i; 5478 } 5479 } 5480 5481 /* we couldn't find one that doesn't fail. Just return something 5482 * and the io error handling code will clean up eventually 5483 */ 5484 return preferred_mirror; 5485 } 5486 5487 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */ 5488 static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes) 5489 { 5490 int i; 5491 int again = 1; 5492 5493 while (again) { 5494 again = 0; 5495 for (i = 0; i < num_stripes - 1; i++) { 5496 /* Swap if parity is on a smaller index */ 5497 if (bbio->raid_map[i] > bbio->raid_map[i + 1]) { 5498 swap(bbio->stripes[i], bbio->stripes[i + 1]); 5499 swap(bbio->raid_map[i], bbio->raid_map[i + 1]); 5500 again = 1; 5501 } 5502 } 5503 } 5504 } 5505 5506 static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes) 5507 { 5508 struct btrfs_bio *bbio = kzalloc( 5509 /* the size of the btrfs_bio */ 5510 sizeof(struct btrfs_bio) + 5511 /* plus the variable array for the stripes */ 5512 sizeof(struct btrfs_bio_stripe) * (total_stripes) + 5513 /* plus the variable array for the tgt dev */ 5514 sizeof(int) * (real_stripes) + 5515 /* 5516 * plus the raid_map, which includes both the tgt dev 5517 * and the stripes 5518 */ 5519 sizeof(u64) * (total_stripes), 5520 GFP_NOFS|__GFP_NOFAIL); 5521 5522 atomic_set(&bbio->error, 0); 5523 refcount_set(&bbio->refs, 1); 5524 5525 return bbio; 5526 } 5527 5528 void btrfs_get_bbio(struct btrfs_bio *bbio) 5529 { 5530 WARN_ON(!refcount_read(&bbio->refs)); 5531 refcount_inc(&bbio->refs); 5532 } 5533 5534 void btrfs_put_bbio(struct btrfs_bio *bbio) 5535 { 5536 if (!bbio) 5537 return; 5538 if (refcount_dec_and_test(&bbio->refs)) 5539 kfree(bbio); 5540 } 5541 5542 /* can REQ_OP_DISCARD be sent with other REQ like REQ_OP_WRITE? */ 5543 /* 5544 * Please note that, discard won't be sent to target device of device 5545 * replace. 5546 */ 5547 static int __btrfs_map_block_for_discard(struct btrfs_fs_info *fs_info, 5548 u64 logical, u64 *length_ret, 5549 struct btrfs_bio **bbio_ret) 5550 { 5551 struct extent_map *em; 5552 struct map_lookup *map; 5553 struct btrfs_bio *bbio; 5554 u64 length = *length_ret; 5555 u64 offset; 5556 u64 stripe_nr; 5557 u64 stripe_nr_end; 5558 u64 stripe_end_offset; 5559 u64 stripe_cnt; 5560 u64 stripe_len; 5561 u64 stripe_offset; 5562 u64 num_stripes; 5563 u32 stripe_index; 5564 u32 factor = 0; 5565 u32 sub_stripes = 0; 5566 u64 stripes_per_dev = 0; 5567 u32 remaining_stripes = 0; 5568 u32 last_stripe = 0; 5569 int ret = 0; 5570 int i; 5571 5572 /* discard always return a bbio */ 5573 ASSERT(bbio_ret); 5574 5575 em = btrfs_get_chunk_map(fs_info, logical, length); 5576 if (IS_ERR(em)) 5577 return PTR_ERR(em); 5578 5579 map = em->map_lookup; 5580 /* we don't discard raid56 yet */ 5581 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { 5582 ret = -EOPNOTSUPP; 5583 goto out; 5584 } 5585 5586 offset = logical - em->start; 5587 length = min_t(u64, em->start + em->len - logical, length); 5588 *length_ret = length; 5589 5590 stripe_len = map->stripe_len; 5591 /* 5592 * stripe_nr counts the total number of stripes we have to stride 5593 * to get to this block 5594 */ 5595 stripe_nr = div64_u64(offset, stripe_len); 5596 5597 /* stripe_offset is the offset of this block in its stripe */ 5598 stripe_offset = offset - stripe_nr * stripe_len; 5599 5600 stripe_nr_end = round_up(offset + length, map->stripe_len); 5601 stripe_nr_end = div64_u64(stripe_nr_end, map->stripe_len); 5602 stripe_cnt = stripe_nr_end - stripe_nr; 5603 stripe_end_offset = stripe_nr_end * map->stripe_len - 5604 (offset + length); 5605 /* 5606 * after this, stripe_nr is the number of stripes on this 5607 * device we have to walk to find the data, and stripe_index is 5608 * the number of our device in the stripe array 5609 */ 5610 num_stripes = 1; 5611 stripe_index = 0; 5612 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | 5613 BTRFS_BLOCK_GROUP_RAID10)) { 5614 if (map->type & BTRFS_BLOCK_GROUP_RAID0) 5615 sub_stripes = 1; 5616 else 5617 sub_stripes = map->sub_stripes; 5618 5619 factor = map->num_stripes / sub_stripes; 5620 num_stripes = min_t(u64, map->num_stripes, 5621 sub_stripes * stripe_cnt); 5622 stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index); 5623 stripe_index *= sub_stripes; 5624 stripes_per_dev = div_u64_rem(stripe_cnt, factor, 5625 &remaining_stripes); 5626 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe); 5627 last_stripe *= sub_stripes; 5628 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID1_MASK | 5629 BTRFS_BLOCK_GROUP_DUP)) { 5630 num_stripes = map->num_stripes; 5631 } else { 5632 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, 5633 &stripe_index); 5634 } 5635 5636 bbio = alloc_btrfs_bio(num_stripes, 0); 5637 if (!bbio) { 5638 ret = -ENOMEM; 5639 goto out; 5640 } 5641 5642 for (i = 0; i < num_stripes; i++) { 5643 bbio->stripes[i].physical = 5644 map->stripes[stripe_index].physical + 5645 stripe_offset + stripe_nr * map->stripe_len; 5646 bbio->stripes[i].dev = map->stripes[stripe_index].dev; 5647 5648 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | 5649 BTRFS_BLOCK_GROUP_RAID10)) { 5650 bbio->stripes[i].length = stripes_per_dev * 5651 map->stripe_len; 5652 5653 if (i / sub_stripes < remaining_stripes) 5654 bbio->stripes[i].length += 5655 map->stripe_len; 5656 5657 /* 5658 * Special for the first stripe and 5659 * the last stripe: 5660 * 5661 * |-------|...|-------| 5662 * |----------| 5663 * off end_off 5664 */ 5665 if (i < sub_stripes) 5666 bbio->stripes[i].length -= 5667 stripe_offset; 5668 5669 if (stripe_index >= last_stripe && 5670 stripe_index <= (last_stripe + 5671 sub_stripes - 1)) 5672 bbio->stripes[i].length -= 5673 stripe_end_offset; 5674 5675 if (i == sub_stripes - 1) 5676 stripe_offset = 0; 5677 } else { 5678 bbio->stripes[i].length = length; 5679 } 5680 5681 stripe_index++; 5682 if (stripe_index == map->num_stripes) { 5683 stripe_index = 0; 5684 stripe_nr++; 5685 } 5686 } 5687 5688 *bbio_ret = bbio; 5689 bbio->map_type = map->type; 5690 bbio->num_stripes = num_stripes; 5691 out: 5692 free_extent_map(em); 5693 return ret; 5694 } 5695 5696 /* 5697 * In dev-replace case, for repair case (that's the only case where the mirror 5698 * is selected explicitly when calling btrfs_map_block), blocks left of the 5699 * left cursor can also be read from the target drive. 5700 * 5701 * For REQ_GET_READ_MIRRORS, the target drive is added as the last one to the 5702 * array of stripes. 5703 * For READ, it also needs to be supported using the same mirror number. 5704 * 5705 * If the requested block is not left of the left cursor, EIO is returned. This 5706 * can happen because btrfs_num_copies() returns one more in the dev-replace 5707 * case. 5708 */ 5709 static int get_extra_mirror_from_replace(struct btrfs_fs_info *fs_info, 5710 u64 logical, u64 length, 5711 u64 srcdev_devid, int *mirror_num, 5712 u64 *physical) 5713 { 5714 struct btrfs_bio *bbio = NULL; 5715 int num_stripes; 5716 int index_srcdev = 0; 5717 int found = 0; 5718 u64 physical_of_found = 0; 5719 int i; 5720 int ret = 0; 5721 5722 ret = __btrfs_map_block(fs_info, BTRFS_MAP_GET_READ_MIRRORS, 5723 logical, &length, &bbio, 0, 0); 5724 if (ret) { 5725 ASSERT(bbio == NULL); 5726 return ret; 5727 } 5728 5729 num_stripes = bbio->num_stripes; 5730 if (*mirror_num > num_stripes) { 5731 /* 5732 * BTRFS_MAP_GET_READ_MIRRORS does not contain this mirror, 5733 * that means that the requested area is not left of the left 5734 * cursor 5735 */ 5736 btrfs_put_bbio(bbio); 5737 return -EIO; 5738 } 5739 5740 /* 5741 * process the rest of the function using the mirror_num of the source 5742 * drive. Therefore look it up first. At the end, patch the device 5743 * pointer to the one of the target drive. 5744 */ 5745 for (i = 0; i < num_stripes; i++) { 5746 if (bbio->stripes[i].dev->devid != srcdev_devid) 5747 continue; 5748 5749 /* 5750 * In case of DUP, in order to keep it simple, only add the 5751 * mirror with the lowest physical address 5752 */ 5753 if (found && 5754 physical_of_found <= bbio->stripes[i].physical) 5755 continue; 5756 5757 index_srcdev = i; 5758 found = 1; 5759 physical_of_found = bbio->stripes[i].physical; 5760 } 5761 5762 btrfs_put_bbio(bbio); 5763 5764 ASSERT(found); 5765 if (!found) 5766 return -EIO; 5767 5768 *mirror_num = index_srcdev + 1; 5769 *physical = physical_of_found; 5770 return ret; 5771 } 5772 5773 static void handle_ops_on_dev_replace(enum btrfs_map_op op, 5774 struct btrfs_bio **bbio_ret, 5775 struct btrfs_dev_replace *dev_replace, 5776 int *num_stripes_ret, int *max_errors_ret) 5777 { 5778 struct btrfs_bio *bbio = *bbio_ret; 5779 u64 srcdev_devid = dev_replace->srcdev->devid; 5780 int tgtdev_indexes = 0; 5781 int num_stripes = *num_stripes_ret; 5782 int max_errors = *max_errors_ret; 5783 int i; 5784 5785 if (op == BTRFS_MAP_WRITE) { 5786 int index_where_to_add; 5787 5788 /* 5789 * duplicate the write operations while the dev replace 5790 * procedure is running. Since the copying of the old disk to 5791 * the new disk takes place at run time while the filesystem is 5792 * mounted writable, the regular write operations to the old 5793 * disk have to be duplicated to go to the new disk as well. 5794 * 5795 * Note that device->missing is handled by the caller, and that 5796 * the write to the old disk is already set up in the stripes 5797 * array. 5798 */ 5799 index_where_to_add = num_stripes; 5800 for (i = 0; i < num_stripes; i++) { 5801 if (bbio->stripes[i].dev->devid == srcdev_devid) { 5802 /* write to new disk, too */ 5803 struct btrfs_bio_stripe *new = 5804 bbio->stripes + index_where_to_add; 5805 struct btrfs_bio_stripe *old = 5806 bbio->stripes + i; 5807 5808 new->physical = old->physical; 5809 new->length = old->length; 5810 new->dev = dev_replace->tgtdev; 5811 bbio->tgtdev_map[i] = index_where_to_add; 5812 index_where_to_add++; 5813 max_errors++; 5814 tgtdev_indexes++; 5815 } 5816 } 5817 num_stripes = index_where_to_add; 5818 } else if (op == BTRFS_MAP_GET_READ_MIRRORS) { 5819 int index_srcdev = 0; 5820 int found = 0; 5821 u64 physical_of_found = 0; 5822 5823 /* 5824 * During the dev-replace procedure, the target drive can also 5825 * be used to read data in case it is needed to repair a corrupt 5826 * block elsewhere. This is possible if the requested area is 5827 * left of the left cursor. In this area, the target drive is a 5828 * full copy of the source drive. 5829 */ 5830 for (i = 0; i < num_stripes; i++) { 5831 if (bbio->stripes[i].dev->devid == srcdev_devid) { 5832 /* 5833 * In case of DUP, in order to keep it simple, 5834 * only add the mirror with the lowest physical 5835 * address 5836 */ 5837 if (found && 5838 physical_of_found <= 5839 bbio->stripes[i].physical) 5840 continue; 5841 index_srcdev = i; 5842 found = 1; 5843 physical_of_found = bbio->stripes[i].physical; 5844 } 5845 } 5846 if (found) { 5847 struct btrfs_bio_stripe *tgtdev_stripe = 5848 bbio->stripes + num_stripes; 5849 5850 tgtdev_stripe->physical = physical_of_found; 5851 tgtdev_stripe->length = 5852 bbio->stripes[index_srcdev].length; 5853 tgtdev_stripe->dev = dev_replace->tgtdev; 5854 bbio->tgtdev_map[index_srcdev] = num_stripes; 5855 5856 tgtdev_indexes++; 5857 num_stripes++; 5858 } 5859 } 5860 5861 *num_stripes_ret = num_stripes; 5862 *max_errors_ret = max_errors; 5863 bbio->num_tgtdevs = tgtdev_indexes; 5864 *bbio_ret = bbio; 5865 } 5866 5867 static bool need_full_stripe(enum btrfs_map_op op) 5868 { 5869 return (op == BTRFS_MAP_WRITE || op == BTRFS_MAP_GET_READ_MIRRORS); 5870 } 5871 5872 /* 5873 * btrfs_get_io_geometry - calculates the geomery of a particular (address, len) 5874 * tuple. This information is used to calculate how big a 5875 * particular bio can get before it straddles a stripe. 5876 * 5877 * @fs_info - the filesystem 5878 * @logical - address that we want to figure out the geometry of 5879 * @len - the length of IO we are going to perform, starting at @logical 5880 * @op - type of operation - write or read 5881 * @io_geom - pointer used to return values 5882 * 5883 * Returns < 0 in case a chunk for the given logical address cannot be found, 5884 * usually shouldn't happen unless @logical is corrupted, 0 otherwise. 5885 */ 5886 int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, 5887 u64 logical, u64 len, struct btrfs_io_geometry *io_geom) 5888 { 5889 struct extent_map *em; 5890 struct map_lookup *map; 5891 u64 offset; 5892 u64 stripe_offset; 5893 u64 stripe_nr; 5894 u64 stripe_len; 5895 u64 raid56_full_stripe_start = (u64)-1; 5896 int data_stripes; 5897 int ret = 0; 5898 5899 ASSERT(op != BTRFS_MAP_DISCARD); 5900 5901 em = btrfs_get_chunk_map(fs_info, logical, len); 5902 if (IS_ERR(em)) 5903 return PTR_ERR(em); 5904 5905 map = em->map_lookup; 5906 /* Offset of this logical address in the chunk */ 5907 offset = logical - em->start; 5908 /* Len of a stripe in a chunk */ 5909 stripe_len = map->stripe_len; 5910 /* Stripe wher this block falls in */ 5911 stripe_nr = div64_u64(offset, stripe_len); 5912 /* Offset of stripe in the chunk */ 5913 stripe_offset = stripe_nr * stripe_len; 5914 if (offset < stripe_offset) { 5915 btrfs_crit(fs_info, 5916 "stripe math has gone wrong, stripe_offset=%llu offset=%llu start=%llu logical=%llu stripe_len=%llu", 5917 stripe_offset, offset, em->start, logical, stripe_len); 5918 ret = -EINVAL; 5919 goto out; 5920 } 5921 5922 /* stripe_offset is the offset of this block in its stripe */ 5923 stripe_offset = offset - stripe_offset; 5924 data_stripes = nr_data_stripes(map); 5925 5926 if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { 5927 u64 max_len = stripe_len - stripe_offset; 5928 5929 /* 5930 * In case of raid56, we need to know the stripe aligned start 5931 */ 5932 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { 5933 unsigned long full_stripe_len = stripe_len * data_stripes; 5934 raid56_full_stripe_start = offset; 5935 5936 /* 5937 * Allow a write of a full stripe, but make sure we 5938 * don't allow straddling of stripes 5939 */ 5940 raid56_full_stripe_start = div64_u64(raid56_full_stripe_start, 5941 full_stripe_len); 5942 raid56_full_stripe_start *= full_stripe_len; 5943 5944 /* 5945 * For writes to RAID[56], allow a full stripeset across 5946 * all disks. For other RAID types and for RAID[56] 5947 * reads, just allow a single stripe (on a single disk). 5948 */ 5949 if (op == BTRFS_MAP_WRITE) { 5950 max_len = stripe_len * data_stripes - 5951 (offset - raid56_full_stripe_start); 5952 } 5953 } 5954 len = min_t(u64, em->len - offset, max_len); 5955 } else { 5956 len = em->len - offset; 5957 } 5958 5959 io_geom->len = len; 5960 io_geom->offset = offset; 5961 io_geom->stripe_len = stripe_len; 5962 io_geom->stripe_nr = stripe_nr; 5963 io_geom->stripe_offset = stripe_offset; 5964 io_geom->raid56_stripe_offset = raid56_full_stripe_start; 5965 5966 out: 5967 /* once for us */ 5968 free_extent_map(em); 5969 return ret; 5970 } 5971 5972 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 5973 enum btrfs_map_op op, 5974 u64 logical, u64 *length, 5975 struct btrfs_bio **bbio_ret, 5976 int mirror_num, int need_raid_map) 5977 { 5978 struct extent_map *em; 5979 struct map_lookup *map; 5980 u64 stripe_offset; 5981 u64 stripe_nr; 5982 u64 stripe_len; 5983 u32 stripe_index; 5984 int data_stripes; 5985 int i; 5986 int ret = 0; 5987 int num_stripes; 5988 int max_errors = 0; 5989 int tgtdev_indexes = 0; 5990 struct btrfs_bio *bbio = NULL; 5991 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 5992 int dev_replace_is_ongoing = 0; 5993 int num_alloc_stripes; 5994 int patch_the_first_stripe_for_dev_replace = 0; 5995 u64 physical_to_patch_in_first_stripe = 0; 5996 u64 raid56_full_stripe_start = (u64)-1; 5997 struct btrfs_io_geometry geom; 5998 5999 ASSERT(bbio_ret); 6000 ASSERT(op != BTRFS_MAP_DISCARD); 6001 6002 ret = btrfs_get_io_geometry(fs_info, op, logical, *length, &geom); 6003 if (ret < 0) 6004 return ret; 6005 6006 em = btrfs_get_chunk_map(fs_info, logical, *length); 6007 ASSERT(!IS_ERR(em)); 6008 map = em->map_lookup; 6009 6010 *length = geom.len; 6011 stripe_len = geom.stripe_len; 6012 stripe_nr = geom.stripe_nr; 6013 stripe_offset = geom.stripe_offset; 6014 raid56_full_stripe_start = geom.raid56_stripe_offset; 6015 data_stripes = nr_data_stripes(map); 6016 6017 down_read(&dev_replace->rwsem); 6018 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace); 6019 /* 6020 * Hold the semaphore for read during the whole operation, write is 6021 * requested at commit time but must wait. 6022 */ 6023 if (!dev_replace_is_ongoing) 6024 up_read(&dev_replace->rwsem); 6025 6026 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 && 6027 !need_full_stripe(op) && dev_replace->tgtdev != NULL) { 6028 ret = get_extra_mirror_from_replace(fs_info, logical, *length, 6029 dev_replace->srcdev->devid, 6030 &mirror_num, 6031 &physical_to_patch_in_first_stripe); 6032 if (ret) 6033 goto out; 6034 else 6035 patch_the_first_stripe_for_dev_replace = 1; 6036 } else if (mirror_num > map->num_stripes) { 6037 mirror_num = 0; 6038 } 6039 6040 num_stripes = 1; 6041 stripe_index = 0; 6042 if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 6043 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, 6044 &stripe_index); 6045 if (!need_full_stripe(op)) 6046 mirror_num = 1; 6047 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1_MASK) { 6048 if (need_full_stripe(op)) 6049 num_stripes = map->num_stripes; 6050 else if (mirror_num) 6051 stripe_index = mirror_num - 1; 6052 else { 6053 stripe_index = find_live_mirror(fs_info, map, 0, 6054 dev_replace_is_ongoing); 6055 mirror_num = stripe_index + 1; 6056 } 6057 6058 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { 6059 if (need_full_stripe(op)) { 6060 num_stripes = map->num_stripes; 6061 } else if (mirror_num) { 6062 stripe_index = mirror_num - 1; 6063 } else { 6064 mirror_num = 1; 6065 } 6066 6067 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 6068 u32 factor = map->num_stripes / map->sub_stripes; 6069 6070 stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index); 6071 stripe_index *= map->sub_stripes; 6072 6073 if (need_full_stripe(op)) 6074 num_stripes = map->sub_stripes; 6075 else if (mirror_num) 6076 stripe_index += mirror_num - 1; 6077 else { 6078 int old_stripe_index = stripe_index; 6079 stripe_index = find_live_mirror(fs_info, map, 6080 stripe_index, 6081 dev_replace_is_ongoing); 6082 mirror_num = stripe_index - old_stripe_index + 1; 6083 } 6084 6085 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { 6086 if (need_raid_map && (need_full_stripe(op) || mirror_num > 1)) { 6087 /* push stripe_nr back to the start of the full stripe */ 6088 stripe_nr = div64_u64(raid56_full_stripe_start, 6089 stripe_len * data_stripes); 6090 6091 /* RAID[56] write or recovery. Return all stripes */ 6092 num_stripes = map->num_stripes; 6093 max_errors = nr_parity_stripes(map); 6094 6095 *length = map->stripe_len; 6096 stripe_index = 0; 6097 stripe_offset = 0; 6098 } else { 6099 /* 6100 * Mirror #0 or #1 means the original data block. 6101 * Mirror #2 is RAID5 parity block. 6102 * Mirror #3 is RAID6 Q block. 6103 */ 6104 stripe_nr = div_u64_rem(stripe_nr, 6105 data_stripes, &stripe_index); 6106 if (mirror_num > 1) 6107 stripe_index = data_stripes + mirror_num - 2; 6108 6109 /* We distribute the parity blocks across stripes */ 6110 div_u64_rem(stripe_nr + stripe_index, map->num_stripes, 6111 &stripe_index); 6112 if (!need_full_stripe(op) && mirror_num <= 1) 6113 mirror_num = 1; 6114 } 6115 } else { 6116 /* 6117 * after this, stripe_nr is the number of stripes on this 6118 * device we have to walk to find the data, and stripe_index is 6119 * the number of our device in the stripe array 6120 */ 6121 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, 6122 &stripe_index); 6123 mirror_num = stripe_index + 1; 6124 } 6125 if (stripe_index >= map->num_stripes) { 6126 btrfs_crit(fs_info, 6127 "stripe index math went horribly wrong, got stripe_index=%u, num_stripes=%u", 6128 stripe_index, map->num_stripes); 6129 ret = -EINVAL; 6130 goto out; 6131 } 6132 6133 num_alloc_stripes = num_stripes; 6134 if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL) { 6135 if (op == BTRFS_MAP_WRITE) 6136 num_alloc_stripes <<= 1; 6137 if (op == BTRFS_MAP_GET_READ_MIRRORS) 6138 num_alloc_stripes++; 6139 tgtdev_indexes = num_stripes; 6140 } 6141 6142 bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes); 6143 if (!bbio) { 6144 ret = -ENOMEM; 6145 goto out; 6146 } 6147 if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL) 6148 bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes); 6149 6150 /* build raid_map */ 6151 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK && need_raid_map && 6152 (need_full_stripe(op) || mirror_num > 1)) { 6153 u64 tmp; 6154 unsigned rot; 6155 6156 bbio->raid_map = (u64 *)((void *)bbio->stripes + 6157 sizeof(struct btrfs_bio_stripe) * 6158 num_alloc_stripes + 6159 sizeof(int) * tgtdev_indexes); 6160 6161 /* Work out the disk rotation on this stripe-set */ 6162 div_u64_rem(stripe_nr, num_stripes, &rot); 6163 6164 /* Fill in the logical address of each stripe */ 6165 tmp = stripe_nr * data_stripes; 6166 for (i = 0; i < data_stripes; i++) 6167 bbio->raid_map[(i+rot) % num_stripes] = 6168 em->start + (tmp + i) * map->stripe_len; 6169 6170 bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE; 6171 if (map->type & BTRFS_BLOCK_GROUP_RAID6) 6172 bbio->raid_map[(i+rot+1) % num_stripes] = 6173 RAID6_Q_STRIPE; 6174 } 6175 6176 6177 for (i = 0; i < num_stripes; i++) { 6178 bbio->stripes[i].physical = 6179 map->stripes[stripe_index].physical + 6180 stripe_offset + 6181 stripe_nr * map->stripe_len; 6182 bbio->stripes[i].dev = 6183 map->stripes[stripe_index].dev; 6184 stripe_index++; 6185 } 6186 6187 if (need_full_stripe(op)) 6188 max_errors = btrfs_chunk_max_errors(map); 6189 6190 if (bbio->raid_map) 6191 sort_parity_stripes(bbio, num_stripes); 6192 6193 if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL && 6194 need_full_stripe(op)) { 6195 handle_ops_on_dev_replace(op, &bbio, dev_replace, &num_stripes, 6196 &max_errors); 6197 } 6198 6199 *bbio_ret = bbio; 6200 bbio->map_type = map->type; 6201 bbio->num_stripes = num_stripes; 6202 bbio->max_errors = max_errors; 6203 bbio->mirror_num = mirror_num; 6204 6205 /* 6206 * this is the case that REQ_READ && dev_replace_is_ongoing && 6207 * mirror_num == num_stripes + 1 && dev_replace target drive is 6208 * available as a mirror 6209 */ 6210 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) { 6211 WARN_ON(num_stripes > 1); 6212 bbio->stripes[0].dev = dev_replace->tgtdev; 6213 bbio->stripes[0].physical = physical_to_patch_in_first_stripe; 6214 bbio->mirror_num = map->num_stripes + 1; 6215 } 6216 out: 6217 if (dev_replace_is_ongoing) { 6218 lockdep_assert_held(&dev_replace->rwsem); 6219 /* Unlock and let waiting writers proceed */ 6220 up_read(&dev_replace->rwsem); 6221 } 6222 free_extent_map(em); 6223 return ret; 6224 } 6225 6226 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, 6227 u64 logical, u64 *length, 6228 struct btrfs_bio **bbio_ret, int mirror_num) 6229 { 6230 if (op == BTRFS_MAP_DISCARD) 6231 return __btrfs_map_block_for_discard(fs_info, logical, 6232 length, bbio_ret); 6233 6234 return __btrfs_map_block(fs_info, op, logical, length, bbio_ret, 6235 mirror_num, 0); 6236 } 6237 6238 /* For Scrub/replace */ 6239 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, 6240 u64 logical, u64 *length, 6241 struct btrfs_bio **bbio_ret) 6242 { 6243 return __btrfs_map_block(fs_info, op, logical, length, bbio_ret, 0, 1); 6244 } 6245 6246 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio) 6247 { 6248 bio->bi_private = bbio->private; 6249 bio->bi_end_io = bbio->end_io; 6250 bio_endio(bio); 6251 6252 btrfs_put_bbio(bbio); 6253 } 6254 6255 static void btrfs_end_bio(struct bio *bio) 6256 { 6257 struct btrfs_bio *bbio = bio->bi_private; 6258 int is_orig_bio = 0; 6259 6260 if (bio->bi_status) { 6261 atomic_inc(&bbio->error); 6262 if (bio->bi_status == BLK_STS_IOERR || 6263 bio->bi_status == BLK_STS_TARGET) { 6264 unsigned int stripe_index = 6265 btrfs_io_bio(bio)->stripe_index; 6266 struct btrfs_device *dev; 6267 6268 BUG_ON(stripe_index >= bbio->num_stripes); 6269 dev = bbio->stripes[stripe_index].dev; 6270 if (dev->bdev) { 6271 if (bio_op(bio) == REQ_OP_WRITE) 6272 btrfs_dev_stat_inc_and_print(dev, 6273 BTRFS_DEV_STAT_WRITE_ERRS); 6274 else if (!(bio->bi_opf & REQ_RAHEAD)) 6275 btrfs_dev_stat_inc_and_print(dev, 6276 BTRFS_DEV_STAT_READ_ERRS); 6277 if (bio->bi_opf & REQ_PREFLUSH) 6278 btrfs_dev_stat_inc_and_print(dev, 6279 BTRFS_DEV_STAT_FLUSH_ERRS); 6280 } 6281 } 6282 } 6283 6284 if (bio == bbio->orig_bio) 6285 is_orig_bio = 1; 6286 6287 btrfs_bio_counter_dec(bbio->fs_info); 6288 6289 if (atomic_dec_and_test(&bbio->stripes_pending)) { 6290 if (!is_orig_bio) { 6291 bio_put(bio); 6292 bio = bbio->orig_bio; 6293 } 6294 6295 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num; 6296 /* only send an error to the higher layers if it is 6297 * beyond the tolerance of the btrfs bio 6298 */ 6299 if (atomic_read(&bbio->error) > bbio->max_errors) { 6300 bio->bi_status = BLK_STS_IOERR; 6301 } else { 6302 /* 6303 * this bio is actually up to date, we didn't 6304 * go over the max number of errors 6305 */ 6306 bio->bi_status = BLK_STS_OK; 6307 } 6308 6309 btrfs_end_bbio(bbio, bio); 6310 } else if (!is_orig_bio) { 6311 bio_put(bio); 6312 } 6313 } 6314 6315 static void submit_stripe_bio(struct btrfs_bio *bbio, struct bio *bio, 6316 u64 physical, int dev_nr) 6317 { 6318 struct btrfs_device *dev = bbio->stripes[dev_nr].dev; 6319 struct btrfs_fs_info *fs_info = bbio->fs_info; 6320 6321 bio->bi_private = bbio; 6322 btrfs_io_bio(bio)->stripe_index = dev_nr; 6323 bio->bi_end_io = btrfs_end_bio; 6324 bio->bi_iter.bi_sector = physical >> 9; 6325 btrfs_debug_in_rcu(fs_info, 6326 "btrfs_map_bio: rw %d 0x%x, sector=%llu, dev=%lu (%s id %llu), size=%u", 6327 bio_op(bio), bio->bi_opf, (u64)bio->bi_iter.bi_sector, 6328 (unsigned long)dev->bdev->bd_dev, rcu_str_deref(dev->name), 6329 dev->devid, bio->bi_iter.bi_size); 6330 bio_set_dev(bio, dev->bdev); 6331 6332 btrfs_bio_counter_inc_noblocked(fs_info); 6333 6334 btrfsic_submit_bio(bio); 6335 } 6336 6337 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) 6338 { 6339 atomic_inc(&bbio->error); 6340 if (atomic_dec_and_test(&bbio->stripes_pending)) { 6341 /* Should be the original bio. */ 6342 WARN_ON(bio != bbio->orig_bio); 6343 6344 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num; 6345 bio->bi_iter.bi_sector = logical >> 9; 6346 if (atomic_read(&bbio->error) > bbio->max_errors) 6347 bio->bi_status = BLK_STS_IOERR; 6348 else 6349 bio->bi_status = BLK_STS_OK; 6350 btrfs_end_bbio(bbio, bio); 6351 } 6352 } 6353 6354 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio, 6355 int mirror_num) 6356 { 6357 struct btrfs_device *dev; 6358 struct bio *first_bio = bio; 6359 u64 logical = (u64)bio->bi_iter.bi_sector << 9; 6360 u64 length = 0; 6361 u64 map_length; 6362 int ret; 6363 int dev_nr; 6364 int total_devs; 6365 struct btrfs_bio *bbio = NULL; 6366 6367 length = bio->bi_iter.bi_size; 6368 map_length = length; 6369 6370 btrfs_bio_counter_inc_blocked(fs_info); 6371 ret = __btrfs_map_block(fs_info, btrfs_op(bio), logical, 6372 &map_length, &bbio, mirror_num, 1); 6373 if (ret) { 6374 btrfs_bio_counter_dec(fs_info); 6375 return errno_to_blk_status(ret); 6376 } 6377 6378 total_devs = bbio->num_stripes; 6379 bbio->orig_bio = first_bio; 6380 bbio->private = first_bio->bi_private; 6381 bbio->end_io = first_bio->bi_end_io; 6382 bbio->fs_info = fs_info; 6383 atomic_set(&bbio->stripes_pending, bbio->num_stripes); 6384 6385 if ((bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) && 6386 ((bio_op(bio) == REQ_OP_WRITE) || (mirror_num > 1))) { 6387 /* In this case, map_length has been set to the length of 6388 a single stripe; not the whole write */ 6389 if (bio_op(bio) == REQ_OP_WRITE) { 6390 ret = raid56_parity_write(fs_info, bio, bbio, 6391 map_length); 6392 } else { 6393 ret = raid56_parity_recover(fs_info, bio, bbio, 6394 map_length, mirror_num, 1); 6395 } 6396 6397 btrfs_bio_counter_dec(fs_info); 6398 return errno_to_blk_status(ret); 6399 } 6400 6401 if (map_length < length) { 6402 btrfs_crit(fs_info, 6403 "mapping failed logical %llu bio len %llu len %llu", 6404 logical, length, map_length); 6405 BUG(); 6406 } 6407 6408 for (dev_nr = 0; dev_nr < total_devs; dev_nr++) { 6409 dev = bbio->stripes[dev_nr].dev; 6410 if (!dev || !dev->bdev || test_bit(BTRFS_DEV_STATE_MISSING, 6411 &dev->dev_state) || 6412 (bio_op(first_bio) == REQ_OP_WRITE && 6413 !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))) { 6414 bbio_error(bbio, first_bio, logical); 6415 continue; 6416 } 6417 6418 if (dev_nr < total_devs - 1) 6419 bio = btrfs_bio_clone(first_bio); 6420 else 6421 bio = first_bio; 6422 6423 submit_stripe_bio(bbio, bio, bbio->stripes[dev_nr].physical, 6424 dev_nr); 6425 } 6426 btrfs_bio_counter_dec(fs_info); 6427 return BLK_STS_OK; 6428 } 6429 6430 /* 6431 * Find a device specified by @devid or @uuid in the list of @fs_devices, or 6432 * return NULL. 6433 * 6434 * If devid and uuid are both specified, the match must be exact, otherwise 6435 * only devid is used. 6436 * 6437 * If @seed is true, traverse through the seed devices. 6438 */ 6439 struct btrfs_device *btrfs_find_device(struct btrfs_fs_devices *fs_devices, 6440 u64 devid, u8 *uuid, u8 *fsid, 6441 bool seed) 6442 { 6443 struct btrfs_device *device; 6444 6445 while (fs_devices) { 6446 if (!fsid || 6447 !memcmp(fs_devices->metadata_uuid, fsid, BTRFS_FSID_SIZE)) { 6448 list_for_each_entry(device, &fs_devices->devices, 6449 dev_list) { 6450 if (device->devid == devid && 6451 (!uuid || memcmp(device->uuid, uuid, 6452 BTRFS_UUID_SIZE) == 0)) 6453 return device; 6454 } 6455 } 6456 if (seed) 6457 fs_devices = fs_devices->seed; 6458 else 6459 return NULL; 6460 } 6461 return NULL; 6462 } 6463 6464 static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices, 6465 u64 devid, u8 *dev_uuid) 6466 { 6467 struct btrfs_device *device; 6468 6469 device = btrfs_alloc_device(NULL, &devid, dev_uuid); 6470 if (IS_ERR(device)) 6471 return device; 6472 6473 list_add(&device->dev_list, &fs_devices->devices); 6474 device->fs_devices = fs_devices; 6475 fs_devices->num_devices++; 6476 6477 set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); 6478 fs_devices->missing_devices++; 6479 6480 return device; 6481 } 6482 6483 /** 6484 * btrfs_alloc_device - allocate struct btrfs_device 6485 * @fs_info: used only for generating a new devid, can be NULL if 6486 * devid is provided (i.e. @devid != NULL). 6487 * @devid: a pointer to devid for this device. If NULL a new devid 6488 * is generated. 6489 * @uuid: a pointer to UUID for this device. If NULL a new UUID 6490 * is generated. 6491 * 6492 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR() 6493 * on error. Returned struct is not linked onto any lists and must be 6494 * destroyed with btrfs_free_device. 6495 */ 6496 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info, 6497 const u64 *devid, 6498 const u8 *uuid) 6499 { 6500 struct btrfs_device *dev; 6501 u64 tmp; 6502 6503 if (WARN_ON(!devid && !fs_info)) 6504 return ERR_PTR(-EINVAL); 6505 6506 dev = __alloc_device(); 6507 if (IS_ERR(dev)) 6508 return dev; 6509 6510 if (devid) 6511 tmp = *devid; 6512 else { 6513 int ret; 6514 6515 ret = find_next_devid(fs_info, &tmp); 6516 if (ret) { 6517 btrfs_free_device(dev); 6518 return ERR_PTR(ret); 6519 } 6520 } 6521 dev->devid = tmp; 6522 6523 if (uuid) 6524 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE); 6525 else 6526 generate_random_uuid(dev->uuid); 6527 6528 return dev; 6529 } 6530 6531 static void btrfs_report_missing_device(struct btrfs_fs_info *fs_info, 6532 u64 devid, u8 *uuid, bool error) 6533 { 6534 if (error) 6535 btrfs_err_rl(fs_info, "devid %llu uuid %pU is missing", 6536 devid, uuid); 6537 else 6538 btrfs_warn_rl(fs_info, "devid %llu uuid %pU is missing", 6539 devid, uuid); 6540 } 6541 6542 static u64 calc_stripe_length(u64 type, u64 chunk_len, int num_stripes) 6543 { 6544 int index = btrfs_bg_flags_to_raid_index(type); 6545 int ncopies = btrfs_raid_array[index].ncopies; 6546 const int nparity = btrfs_raid_array[index].nparity; 6547 int data_stripes; 6548 6549 if (nparity) 6550 data_stripes = num_stripes - nparity; 6551 else 6552 data_stripes = num_stripes / ncopies; 6553 6554 return div_u64(chunk_len, data_stripes); 6555 } 6556 6557 static int read_one_chunk(struct btrfs_key *key, struct extent_buffer *leaf, 6558 struct btrfs_chunk *chunk) 6559 { 6560 struct btrfs_fs_info *fs_info = leaf->fs_info; 6561 struct extent_map_tree *map_tree = &fs_info->mapping_tree; 6562 struct map_lookup *map; 6563 struct extent_map *em; 6564 u64 logical; 6565 u64 length; 6566 u64 devid; 6567 u8 uuid[BTRFS_UUID_SIZE]; 6568 int num_stripes; 6569 int ret; 6570 int i; 6571 6572 logical = key->offset; 6573 length = btrfs_chunk_length(leaf, chunk); 6574 num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 6575 6576 /* 6577 * Only need to verify chunk item if we're reading from sys chunk array, 6578 * as chunk item in tree block is already verified by tree-checker. 6579 */ 6580 if (leaf->start == BTRFS_SUPER_INFO_OFFSET) { 6581 ret = btrfs_check_chunk_valid(leaf, chunk, logical); 6582 if (ret) 6583 return ret; 6584 } 6585 6586 read_lock(&map_tree->lock); 6587 em = lookup_extent_mapping(map_tree, logical, 1); 6588 read_unlock(&map_tree->lock); 6589 6590 /* already mapped? */ 6591 if (em && em->start <= logical && em->start + em->len > logical) { 6592 free_extent_map(em); 6593 return 0; 6594 } else if (em) { 6595 free_extent_map(em); 6596 } 6597 6598 em = alloc_extent_map(); 6599 if (!em) 6600 return -ENOMEM; 6601 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 6602 if (!map) { 6603 free_extent_map(em); 6604 return -ENOMEM; 6605 } 6606 6607 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags); 6608 em->map_lookup = map; 6609 em->start = logical; 6610 em->len = length; 6611 em->orig_start = 0; 6612 em->block_start = 0; 6613 em->block_len = em->len; 6614 6615 map->num_stripes = num_stripes; 6616 map->io_width = btrfs_chunk_io_width(leaf, chunk); 6617 map->io_align = btrfs_chunk_io_align(leaf, chunk); 6618 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); 6619 map->type = btrfs_chunk_type(leaf, chunk); 6620 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); 6621 map->verified_stripes = 0; 6622 em->orig_block_len = calc_stripe_length(map->type, em->len, 6623 map->num_stripes); 6624 for (i = 0; i < num_stripes; i++) { 6625 map->stripes[i].physical = 6626 btrfs_stripe_offset_nr(leaf, chunk, i); 6627 devid = btrfs_stripe_devid_nr(leaf, chunk, i); 6628 read_extent_buffer(leaf, uuid, (unsigned long) 6629 btrfs_stripe_dev_uuid_nr(chunk, i), 6630 BTRFS_UUID_SIZE); 6631 map->stripes[i].dev = btrfs_find_device(fs_info->fs_devices, 6632 devid, uuid, NULL, true); 6633 if (!map->stripes[i].dev && 6634 !btrfs_test_opt(fs_info, DEGRADED)) { 6635 free_extent_map(em); 6636 btrfs_report_missing_device(fs_info, devid, uuid, true); 6637 return -ENOENT; 6638 } 6639 if (!map->stripes[i].dev) { 6640 map->stripes[i].dev = 6641 add_missing_dev(fs_info->fs_devices, devid, 6642 uuid); 6643 if (IS_ERR(map->stripes[i].dev)) { 6644 free_extent_map(em); 6645 btrfs_err(fs_info, 6646 "failed to init missing dev %llu: %ld", 6647 devid, PTR_ERR(map->stripes[i].dev)); 6648 return PTR_ERR(map->stripes[i].dev); 6649 } 6650 btrfs_report_missing_device(fs_info, devid, uuid, false); 6651 } 6652 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, 6653 &(map->stripes[i].dev->dev_state)); 6654 6655 } 6656 6657 write_lock(&map_tree->lock); 6658 ret = add_extent_mapping(map_tree, em, 0); 6659 write_unlock(&map_tree->lock); 6660 if (ret < 0) { 6661 btrfs_err(fs_info, 6662 "failed to add chunk map, start=%llu len=%llu: %d", 6663 em->start, em->len, ret); 6664 } 6665 free_extent_map(em); 6666 6667 return ret; 6668 } 6669 6670 static void fill_device_from_item(struct extent_buffer *leaf, 6671 struct btrfs_dev_item *dev_item, 6672 struct btrfs_device *device) 6673 { 6674 unsigned long ptr; 6675 6676 device->devid = btrfs_device_id(leaf, dev_item); 6677 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); 6678 device->total_bytes = device->disk_total_bytes; 6679 device->commit_total_bytes = device->disk_total_bytes; 6680 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); 6681 device->commit_bytes_used = device->bytes_used; 6682 device->type = btrfs_device_type(leaf, dev_item); 6683 device->io_align = btrfs_device_io_align(leaf, dev_item); 6684 device->io_width = btrfs_device_io_width(leaf, dev_item); 6685 device->sector_size = btrfs_device_sector_size(leaf, dev_item); 6686 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); 6687 clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); 6688 6689 ptr = btrfs_device_uuid(dev_item); 6690 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 6691 } 6692 6693 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_fs_info *fs_info, 6694 u8 *fsid) 6695 { 6696 struct btrfs_fs_devices *fs_devices; 6697 int ret; 6698 6699 lockdep_assert_held(&uuid_mutex); 6700 ASSERT(fsid); 6701 6702 fs_devices = fs_info->fs_devices->seed; 6703 while (fs_devices) { 6704 if (!memcmp(fs_devices->fsid, fsid, BTRFS_FSID_SIZE)) 6705 return fs_devices; 6706 6707 fs_devices = fs_devices->seed; 6708 } 6709 6710 fs_devices = find_fsid(fsid, NULL); 6711 if (!fs_devices) { 6712 if (!btrfs_test_opt(fs_info, DEGRADED)) 6713 return ERR_PTR(-ENOENT); 6714 6715 fs_devices = alloc_fs_devices(fsid, NULL); 6716 if (IS_ERR(fs_devices)) 6717 return fs_devices; 6718 6719 fs_devices->seeding = true; 6720 fs_devices->opened = 1; 6721 return fs_devices; 6722 } 6723 6724 fs_devices = clone_fs_devices(fs_devices); 6725 if (IS_ERR(fs_devices)) 6726 return fs_devices; 6727 6728 ret = open_fs_devices(fs_devices, FMODE_READ, fs_info->bdev_holder); 6729 if (ret) { 6730 free_fs_devices(fs_devices); 6731 fs_devices = ERR_PTR(ret); 6732 goto out; 6733 } 6734 6735 if (!fs_devices->seeding) { 6736 close_fs_devices(fs_devices); 6737 free_fs_devices(fs_devices); 6738 fs_devices = ERR_PTR(-EINVAL); 6739 goto out; 6740 } 6741 6742 fs_devices->seed = fs_info->fs_devices->seed; 6743 fs_info->fs_devices->seed = fs_devices; 6744 out: 6745 return fs_devices; 6746 } 6747 6748 static int read_one_dev(struct extent_buffer *leaf, 6749 struct btrfs_dev_item *dev_item) 6750 { 6751 struct btrfs_fs_info *fs_info = leaf->fs_info; 6752 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 6753 struct btrfs_device *device; 6754 u64 devid; 6755 int ret; 6756 u8 fs_uuid[BTRFS_FSID_SIZE]; 6757 u8 dev_uuid[BTRFS_UUID_SIZE]; 6758 6759 devid = btrfs_device_id(leaf, dev_item); 6760 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item), 6761 BTRFS_UUID_SIZE); 6762 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item), 6763 BTRFS_FSID_SIZE); 6764 6765 if (memcmp(fs_uuid, fs_devices->metadata_uuid, BTRFS_FSID_SIZE)) { 6766 fs_devices = open_seed_devices(fs_info, fs_uuid); 6767 if (IS_ERR(fs_devices)) 6768 return PTR_ERR(fs_devices); 6769 } 6770 6771 device = btrfs_find_device(fs_info->fs_devices, devid, dev_uuid, 6772 fs_uuid, true); 6773 if (!device) { 6774 if (!btrfs_test_opt(fs_info, DEGRADED)) { 6775 btrfs_report_missing_device(fs_info, devid, 6776 dev_uuid, true); 6777 return -ENOENT; 6778 } 6779 6780 device = add_missing_dev(fs_devices, devid, dev_uuid); 6781 if (IS_ERR(device)) { 6782 btrfs_err(fs_info, 6783 "failed to add missing dev %llu: %ld", 6784 devid, PTR_ERR(device)); 6785 return PTR_ERR(device); 6786 } 6787 btrfs_report_missing_device(fs_info, devid, dev_uuid, false); 6788 } else { 6789 if (!device->bdev) { 6790 if (!btrfs_test_opt(fs_info, DEGRADED)) { 6791 btrfs_report_missing_device(fs_info, 6792 devid, dev_uuid, true); 6793 return -ENOENT; 6794 } 6795 btrfs_report_missing_device(fs_info, devid, 6796 dev_uuid, false); 6797 } 6798 6799 if (!device->bdev && 6800 !test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) { 6801 /* 6802 * this happens when a device that was properly setup 6803 * in the device info lists suddenly goes bad. 6804 * device->bdev is NULL, and so we have to set 6805 * device->missing to one here 6806 */ 6807 device->fs_devices->missing_devices++; 6808 set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); 6809 } 6810 6811 /* Move the device to its own fs_devices */ 6812 if (device->fs_devices != fs_devices) { 6813 ASSERT(test_bit(BTRFS_DEV_STATE_MISSING, 6814 &device->dev_state)); 6815 6816 list_move(&device->dev_list, &fs_devices->devices); 6817 device->fs_devices->num_devices--; 6818 fs_devices->num_devices++; 6819 6820 device->fs_devices->missing_devices--; 6821 fs_devices->missing_devices++; 6822 6823 device->fs_devices = fs_devices; 6824 } 6825 } 6826 6827 if (device->fs_devices != fs_info->fs_devices) { 6828 BUG_ON(test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)); 6829 if (device->generation != 6830 btrfs_device_generation(leaf, dev_item)) 6831 return -EINVAL; 6832 } 6833 6834 fill_device_from_item(leaf, dev_item, device); 6835 set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); 6836 if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && 6837 !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { 6838 device->fs_devices->total_rw_bytes += device->total_bytes; 6839 atomic64_add(device->total_bytes - device->bytes_used, 6840 &fs_info->free_chunk_space); 6841 } 6842 ret = 0; 6843 return ret; 6844 } 6845 6846 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info) 6847 { 6848 struct btrfs_root *root = fs_info->tree_root; 6849 struct btrfs_super_block *super_copy = fs_info->super_copy; 6850 struct extent_buffer *sb; 6851 struct btrfs_disk_key *disk_key; 6852 struct btrfs_chunk *chunk; 6853 u8 *array_ptr; 6854 unsigned long sb_array_offset; 6855 int ret = 0; 6856 u32 num_stripes; 6857 u32 array_size; 6858 u32 len = 0; 6859 u32 cur_offset; 6860 u64 type; 6861 struct btrfs_key key; 6862 6863 ASSERT(BTRFS_SUPER_INFO_SIZE <= fs_info->nodesize); 6864 /* 6865 * This will create extent buffer of nodesize, superblock size is 6866 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will 6867 * overallocate but we can keep it as-is, only the first page is used. 6868 */ 6869 sb = btrfs_find_create_tree_block(fs_info, BTRFS_SUPER_INFO_OFFSET); 6870 if (IS_ERR(sb)) 6871 return PTR_ERR(sb); 6872 set_extent_buffer_uptodate(sb); 6873 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); 6874 /* 6875 * The sb extent buffer is artificial and just used to read the system array. 6876 * set_extent_buffer_uptodate() call does not properly mark all it's 6877 * pages up-to-date when the page is larger: extent does not cover the 6878 * whole page and consequently check_page_uptodate does not find all 6879 * the page's extents up-to-date (the hole beyond sb), 6880 * write_extent_buffer then triggers a WARN_ON. 6881 * 6882 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle, 6883 * but sb spans only this function. Add an explicit SetPageUptodate call 6884 * to silence the warning eg. on PowerPC 64. 6885 */ 6886 if (PAGE_SIZE > BTRFS_SUPER_INFO_SIZE) 6887 SetPageUptodate(sb->pages[0]); 6888 6889 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); 6890 array_size = btrfs_super_sys_array_size(super_copy); 6891 6892 array_ptr = super_copy->sys_chunk_array; 6893 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array); 6894 cur_offset = 0; 6895 6896 while (cur_offset < array_size) { 6897 disk_key = (struct btrfs_disk_key *)array_ptr; 6898 len = sizeof(*disk_key); 6899 if (cur_offset + len > array_size) 6900 goto out_short_read; 6901 6902 btrfs_disk_key_to_cpu(&key, disk_key); 6903 6904 array_ptr += len; 6905 sb_array_offset += len; 6906 cur_offset += len; 6907 6908 if (key.type != BTRFS_CHUNK_ITEM_KEY) { 6909 btrfs_err(fs_info, 6910 "unexpected item type %u in sys_array at offset %u", 6911 (u32)key.type, cur_offset); 6912 ret = -EIO; 6913 break; 6914 } 6915 6916 chunk = (struct btrfs_chunk *)sb_array_offset; 6917 /* 6918 * At least one btrfs_chunk with one stripe must be present, 6919 * exact stripe count check comes afterwards 6920 */ 6921 len = btrfs_chunk_item_size(1); 6922 if (cur_offset + len > array_size) 6923 goto out_short_read; 6924 6925 num_stripes = btrfs_chunk_num_stripes(sb, chunk); 6926 if (!num_stripes) { 6927 btrfs_err(fs_info, 6928 "invalid number of stripes %u in sys_array at offset %u", 6929 num_stripes, cur_offset); 6930 ret = -EIO; 6931 break; 6932 } 6933 6934 type = btrfs_chunk_type(sb, chunk); 6935 if ((type & BTRFS_BLOCK_GROUP_SYSTEM) == 0) { 6936 btrfs_err(fs_info, 6937 "invalid chunk type %llu in sys_array at offset %u", 6938 type, cur_offset); 6939 ret = -EIO; 6940 break; 6941 } 6942 6943 len = btrfs_chunk_item_size(num_stripes); 6944 if (cur_offset + len > array_size) 6945 goto out_short_read; 6946 6947 ret = read_one_chunk(&key, sb, chunk); 6948 if (ret) 6949 break; 6950 6951 array_ptr += len; 6952 sb_array_offset += len; 6953 cur_offset += len; 6954 } 6955 clear_extent_buffer_uptodate(sb); 6956 free_extent_buffer_stale(sb); 6957 return ret; 6958 6959 out_short_read: 6960 btrfs_err(fs_info, "sys_array too short to read %u bytes at offset %u", 6961 len, cur_offset); 6962 clear_extent_buffer_uptodate(sb); 6963 free_extent_buffer_stale(sb); 6964 return -EIO; 6965 } 6966 6967 /* 6968 * Check if all chunks in the fs are OK for read-write degraded mount 6969 * 6970 * If the @failing_dev is specified, it's accounted as missing. 6971 * 6972 * Return true if all chunks meet the minimal RW mount requirements. 6973 * Return false if any chunk doesn't meet the minimal RW mount requirements. 6974 */ 6975 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info, 6976 struct btrfs_device *failing_dev) 6977 { 6978 struct extent_map_tree *map_tree = &fs_info->mapping_tree; 6979 struct extent_map *em; 6980 u64 next_start = 0; 6981 bool ret = true; 6982 6983 read_lock(&map_tree->lock); 6984 em = lookup_extent_mapping(map_tree, 0, (u64)-1); 6985 read_unlock(&map_tree->lock); 6986 /* No chunk at all? Return false anyway */ 6987 if (!em) { 6988 ret = false; 6989 goto out; 6990 } 6991 while (em) { 6992 struct map_lookup *map; 6993 int missing = 0; 6994 int max_tolerated; 6995 int i; 6996 6997 map = em->map_lookup; 6998 max_tolerated = 6999 btrfs_get_num_tolerated_disk_barrier_failures( 7000 map->type); 7001 for (i = 0; i < map->num_stripes; i++) { 7002 struct btrfs_device *dev = map->stripes[i].dev; 7003 7004 if (!dev || !dev->bdev || 7005 test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) || 7006 dev->last_flush_error) 7007 missing++; 7008 else if (failing_dev && failing_dev == dev) 7009 missing++; 7010 } 7011 if (missing > max_tolerated) { 7012 if (!failing_dev) 7013 btrfs_warn(fs_info, 7014 "chunk %llu missing %d devices, max tolerance is %d for writable mount", 7015 em->start, missing, max_tolerated); 7016 free_extent_map(em); 7017 ret = false; 7018 goto out; 7019 } 7020 next_start = extent_map_end(em); 7021 free_extent_map(em); 7022 7023 read_lock(&map_tree->lock); 7024 em = lookup_extent_mapping(map_tree, next_start, 7025 (u64)(-1) - next_start); 7026 read_unlock(&map_tree->lock); 7027 } 7028 out: 7029 return ret; 7030 } 7031 7032 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info) 7033 { 7034 struct btrfs_root *root = fs_info->chunk_root; 7035 struct btrfs_path *path; 7036 struct extent_buffer *leaf; 7037 struct btrfs_key key; 7038 struct btrfs_key found_key; 7039 int ret; 7040 int slot; 7041 u64 total_dev = 0; 7042 7043 path = btrfs_alloc_path(); 7044 if (!path) 7045 return -ENOMEM; 7046 7047 /* 7048 * uuid_mutex is needed only if we are mounting a sprout FS 7049 * otherwise we don't need it. 7050 */ 7051 mutex_lock(&uuid_mutex); 7052 mutex_lock(&fs_info->chunk_mutex); 7053 7054 /* 7055 * Read all device items, and then all the chunk items. All 7056 * device items are found before any chunk item (their object id 7057 * is smaller than the lowest possible object id for a chunk 7058 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID). 7059 */ 7060 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 7061 key.offset = 0; 7062 key.type = 0; 7063 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 7064 if (ret < 0) 7065 goto error; 7066 while (1) { 7067 leaf = path->nodes[0]; 7068 slot = path->slots[0]; 7069 if (slot >= btrfs_header_nritems(leaf)) { 7070 ret = btrfs_next_leaf(root, path); 7071 if (ret == 0) 7072 continue; 7073 if (ret < 0) 7074 goto error; 7075 break; 7076 } 7077 btrfs_item_key_to_cpu(leaf, &found_key, slot); 7078 if (found_key.type == BTRFS_DEV_ITEM_KEY) { 7079 struct btrfs_dev_item *dev_item; 7080 dev_item = btrfs_item_ptr(leaf, slot, 7081 struct btrfs_dev_item); 7082 ret = read_one_dev(leaf, dev_item); 7083 if (ret) 7084 goto error; 7085 total_dev++; 7086 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { 7087 struct btrfs_chunk *chunk; 7088 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 7089 ret = read_one_chunk(&found_key, leaf, chunk); 7090 if (ret) 7091 goto error; 7092 } 7093 path->slots[0]++; 7094 } 7095 7096 /* 7097 * After loading chunk tree, we've got all device information, 7098 * do another round of validation checks. 7099 */ 7100 if (total_dev != fs_info->fs_devices->total_devices) { 7101 btrfs_err(fs_info, 7102 "super_num_devices %llu mismatch with num_devices %llu found here", 7103 btrfs_super_num_devices(fs_info->super_copy), 7104 total_dev); 7105 ret = -EINVAL; 7106 goto error; 7107 } 7108 if (btrfs_super_total_bytes(fs_info->super_copy) < 7109 fs_info->fs_devices->total_rw_bytes) { 7110 btrfs_err(fs_info, 7111 "super_total_bytes %llu mismatch with fs_devices total_rw_bytes %llu", 7112 btrfs_super_total_bytes(fs_info->super_copy), 7113 fs_info->fs_devices->total_rw_bytes); 7114 ret = -EINVAL; 7115 goto error; 7116 } 7117 ret = 0; 7118 error: 7119 mutex_unlock(&fs_info->chunk_mutex); 7120 mutex_unlock(&uuid_mutex); 7121 7122 btrfs_free_path(path); 7123 return ret; 7124 } 7125 7126 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info) 7127 { 7128 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 7129 struct btrfs_device *device; 7130 7131 while (fs_devices) { 7132 mutex_lock(&fs_devices->device_list_mutex); 7133 list_for_each_entry(device, &fs_devices->devices, dev_list) 7134 device->fs_info = fs_info; 7135 mutex_unlock(&fs_devices->device_list_mutex); 7136 7137 fs_devices = fs_devices->seed; 7138 } 7139 } 7140 7141 static u64 btrfs_dev_stats_value(const struct extent_buffer *eb, 7142 const struct btrfs_dev_stats_item *ptr, 7143 int index) 7144 { 7145 u64 val; 7146 7147 read_extent_buffer(eb, &val, 7148 offsetof(struct btrfs_dev_stats_item, values) + 7149 ((unsigned long)ptr) + (index * sizeof(u64)), 7150 sizeof(val)); 7151 return val; 7152 } 7153 7154 static void btrfs_set_dev_stats_value(struct extent_buffer *eb, 7155 struct btrfs_dev_stats_item *ptr, 7156 int index, u64 val) 7157 { 7158 write_extent_buffer(eb, &val, 7159 offsetof(struct btrfs_dev_stats_item, values) + 7160 ((unsigned long)ptr) + (index * sizeof(u64)), 7161 sizeof(val)); 7162 } 7163 7164 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) 7165 { 7166 struct btrfs_key key; 7167 struct btrfs_root *dev_root = fs_info->dev_root; 7168 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 7169 struct extent_buffer *eb; 7170 int slot; 7171 int ret = 0; 7172 struct btrfs_device *device; 7173 struct btrfs_path *path = NULL; 7174 int i; 7175 7176 path = btrfs_alloc_path(); 7177 if (!path) 7178 return -ENOMEM; 7179 7180 mutex_lock(&fs_devices->device_list_mutex); 7181 list_for_each_entry(device, &fs_devices->devices, dev_list) { 7182 int item_size; 7183 struct btrfs_dev_stats_item *ptr; 7184 7185 key.objectid = BTRFS_DEV_STATS_OBJECTID; 7186 key.type = BTRFS_PERSISTENT_ITEM_KEY; 7187 key.offset = device->devid; 7188 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 7189 if (ret) { 7190 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 7191 btrfs_dev_stat_set(device, i, 0); 7192 device->dev_stats_valid = 1; 7193 btrfs_release_path(path); 7194 continue; 7195 } 7196 slot = path->slots[0]; 7197 eb = path->nodes[0]; 7198 item_size = btrfs_item_size_nr(eb, slot); 7199 7200 ptr = btrfs_item_ptr(eb, slot, 7201 struct btrfs_dev_stats_item); 7202 7203 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 7204 if (item_size >= (1 + i) * sizeof(__le64)) 7205 btrfs_dev_stat_set(device, i, 7206 btrfs_dev_stats_value(eb, ptr, i)); 7207 else 7208 btrfs_dev_stat_set(device, i, 0); 7209 } 7210 7211 device->dev_stats_valid = 1; 7212 btrfs_dev_stat_print_on_load(device); 7213 btrfs_release_path(path); 7214 } 7215 mutex_unlock(&fs_devices->device_list_mutex); 7216 7217 btrfs_free_path(path); 7218 return ret < 0 ? ret : 0; 7219 } 7220 7221 static int update_dev_stat_item(struct btrfs_trans_handle *trans, 7222 struct btrfs_device *device) 7223 { 7224 struct btrfs_fs_info *fs_info = trans->fs_info; 7225 struct btrfs_root *dev_root = fs_info->dev_root; 7226 struct btrfs_path *path; 7227 struct btrfs_key key; 7228 struct extent_buffer *eb; 7229 struct btrfs_dev_stats_item *ptr; 7230 int ret; 7231 int i; 7232 7233 key.objectid = BTRFS_DEV_STATS_OBJECTID; 7234 key.type = BTRFS_PERSISTENT_ITEM_KEY; 7235 key.offset = device->devid; 7236 7237 path = btrfs_alloc_path(); 7238 if (!path) 7239 return -ENOMEM; 7240 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 7241 if (ret < 0) { 7242 btrfs_warn_in_rcu(fs_info, 7243 "error %d while searching for dev_stats item for device %s", 7244 ret, rcu_str_deref(device->name)); 7245 goto out; 7246 } 7247 7248 if (ret == 0 && 7249 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 7250 /* need to delete old one and insert a new one */ 7251 ret = btrfs_del_item(trans, dev_root, path); 7252 if (ret != 0) { 7253 btrfs_warn_in_rcu(fs_info, 7254 "delete too small dev_stats item for device %s failed %d", 7255 rcu_str_deref(device->name), ret); 7256 goto out; 7257 } 7258 ret = 1; 7259 } 7260 7261 if (ret == 1) { 7262 /* need to insert a new item */ 7263 btrfs_release_path(path); 7264 ret = btrfs_insert_empty_item(trans, dev_root, path, 7265 &key, sizeof(*ptr)); 7266 if (ret < 0) { 7267 btrfs_warn_in_rcu(fs_info, 7268 "insert dev_stats item for device %s failed %d", 7269 rcu_str_deref(device->name), ret); 7270 goto out; 7271 } 7272 } 7273 7274 eb = path->nodes[0]; 7275 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); 7276 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 7277 btrfs_set_dev_stats_value(eb, ptr, i, 7278 btrfs_dev_stat_read(device, i)); 7279 btrfs_mark_buffer_dirty(eb); 7280 7281 out: 7282 btrfs_free_path(path); 7283 return ret; 7284 } 7285 7286 /* 7287 * called from commit_transaction. Writes all changed device stats to disk. 7288 */ 7289 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans) 7290 { 7291 struct btrfs_fs_info *fs_info = trans->fs_info; 7292 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 7293 struct btrfs_device *device; 7294 int stats_cnt; 7295 int ret = 0; 7296 7297 mutex_lock(&fs_devices->device_list_mutex); 7298 list_for_each_entry(device, &fs_devices->devices, dev_list) { 7299 stats_cnt = atomic_read(&device->dev_stats_ccnt); 7300 if (!device->dev_stats_valid || stats_cnt == 0) 7301 continue; 7302 7303 7304 /* 7305 * There is a LOAD-LOAD control dependency between the value of 7306 * dev_stats_ccnt and updating the on-disk values which requires 7307 * reading the in-memory counters. Such control dependencies 7308 * require explicit read memory barriers. 7309 * 7310 * This memory barriers pairs with smp_mb__before_atomic in 7311 * btrfs_dev_stat_inc/btrfs_dev_stat_set and with the full 7312 * barrier implied by atomic_xchg in 7313 * btrfs_dev_stats_read_and_reset 7314 */ 7315 smp_rmb(); 7316 7317 ret = update_dev_stat_item(trans, device); 7318 if (!ret) 7319 atomic_sub(stats_cnt, &device->dev_stats_ccnt); 7320 } 7321 mutex_unlock(&fs_devices->device_list_mutex); 7322 7323 return ret; 7324 } 7325 7326 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) 7327 { 7328 btrfs_dev_stat_inc(dev, index); 7329 btrfs_dev_stat_print_on_error(dev); 7330 } 7331 7332 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev) 7333 { 7334 if (!dev->dev_stats_valid) 7335 return; 7336 btrfs_err_rl_in_rcu(dev->fs_info, 7337 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u", 7338 rcu_str_deref(dev->name), 7339 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 7340 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 7341 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 7342 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), 7343 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); 7344 } 7345 7346 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) 7347 { 7348 int i; 7349 7350 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 7351 if (btrfs_dev_stat_read(dev, i) != 0) 7352 break; 7353 if (i == BTRFS_DEV_STAT_VALUES_MAX) 7354 return; /* all values == 0, suppress message */ 7355 7356 btrfs_info_in_rcu(dev->fs_info, 7357 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u", 7358 rcu_str_deref(dev->name), 7359 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 7360 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 7361 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 7362 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), 7363 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); 7364 } 7365 7366 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info, 7367 struct btrfs_ioctl_get_dev_stats *stats) 7368 { 7369 struct btrfs_device *dev; 7370 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 7371 int i; 7372 7373 mutex_lock(&fs_devices->device_list_mutex); 7374 dev = btrfs_find_device(fs_info->fs_devices, stats->devid, NULL, NULL, 7375 true); 7376 mutex_unlock(&fs_devices->device_list_mutex); 7377 7378 if (!dev) { 7379 btrfs_warn(fs_info, "get dev_stats failed, device not found"); 7380 return -ENODEV; 7381 } else if (!dev->dev_stats_valid) { 7382 btrfs_warn(fs_info, "get dev_stats failed, not yet valid"); 7383 return -ENODEV; 7384 } else if (stats->flags & BTRFS_DEV_STATS_RESET) { 7385 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 7386 if (stats->nr_items > i) 7387 stats->values[i] = 7388 btrfs_dev_stat_read_and_reset(dev, i); 7389 else 7390 btrfs_dev_stat_set(dev, i, 0); 7391 } 7392 btrfs_info(fs_info, "device stats zeroed by %s (%d)", 7393 current->comm, task_pid_nr(current)); 7394 } else { 7395 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 7396 if (stats->nr_items > i) 7397 stats->values[i] = btrfs_dev_stat_read(dev, i); 7398 } 7399 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) 7400 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; 7401 return 0; 7402 } 7403 7404 /* 7405 * Update the size and bytes used for each device where it changed. This is 7406 * delayed since we would otherwise get errors while writing out the 7407 * superblocks. 7408 * 7409 * Must be invoked during transaction commit. 7410 */ 7411 void btrfs_commit_device_sizes(struct btrfs_transaction *trans) 7412 { 7413 struct btrfs_device *curr, *next; 7414 7415 ASSERT(trans->state == TRANS_STATE_COMMIT_DOING); 7416 7417 if (list_empty(&trans->dev_update_list)) 7418 return; 7419 7420 /* 7421 * We don't need the device_list_mutex here. This list is owned by the 7422 * transaction and the transaction must complete before the device is 7423 * released. 7424 */ 7425 mutex_lock(&trans->fs_info->chunk_mutex); 7426 list_for_each_entry_safe(curr, next, &trans->dev_update_list, 7427 post_commit_list) { 7428 list_del_init(&curr->post_commit_list); 7429 curr->commit_total_bytes = curr->disk_total_bytes; 7430 curr->commit_bytes_used = curr->bytes_used; 7431 } 7432 mutex_unlock(&trans->fs_info->chunk_mutex); 7433 } 7434 7435 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info) 7436 { 7437 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 7438 while (fs_devices) { 7439 fs_devices->fs_info = fs_info; 7440 fs_devices = fs_devices->seed; 7441 } 7442 } 7443 7444 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info) 7445 { 7446 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 7447 while (fs_devices) { 7448 fs_devices->fs_info = NULL; 7449 fs_devices = fs_devices->seed; 7450 } 7451 } 7452 7453 /* 7454 * Multiplicity factor for simple profiles: DUP, RAID1-like and RAID10. 7455 */ 7456 int btrfs_bg_type_to_factor(u64 flags) 7457 { 7458 const int index = btrfs_bg_flags_to_raid_index(flags); 7459 7460 return btrfs_raid_array[index].ncopies; 7461 } 7462 7463 7464 7465 static int verify_one_dev_extent(struct btrfs_fs_info *fs_info, 7466 u64 chunk_offset, u64 devid, 7467 u64 physical_offset, u64 physical_len) 7468 { 7469 struct extent_map_tree *em_tree = &fs_info->mapping_tree; 7470 struct extent_map *em; 7471 struct map_lookup *map; 7472 struct btrfs_device *dev; 7473 u64 stripe_len; 7474 bool found = false; 7475 int ret = 0; 7476 int i; 7477 7478 read_lock(&em_tree->lock); 7479 em = lookup_extent_mapping(em_tree, chunk_offset, 1); 7480 read_unlock(&em_tree->lock); 7481 7482 if (!em) { 7483 btrfs_err(fs_info, 7484 "dev extent physical offset %llu on devid %llu doesn't have corresponding chunk", 7485 physical_offset, devid); 7486 ret = -EUCLEAN; 7487 goto out; 7488 } 7489 7490 map = em->map_lookup; 7491 stripe_len = calc_stripe_length(map->type, em->len, map->num_stripes); 7492 if (physical_len != stripe_len) { 7493 btrfs_err(fs_info, 7494 "dev extent physical offset %llu on devid %llu length doesn't match chunk %llu, have %llu expect %llu", 7495 physical_offset, devid, em->start, physical_len, 7496 stripe_len); 7497 ret = -EUCLEAN; 7498 goto out; 7499 } 7500 7501 for (i = 0; i < map->num_stripes; i++) { 7502 if (map->stripes[i].dev->devid == devid && 7503 map->stripes[i].physical == physical_offset) { 7504 found = true; 7505 if (map->verified_stripes >= map->num_stripes) { 7506 btrfs_err(fs_info, 7507 "too many dev extents for chunk %llu found", 7508 em->start); 7509 ret = -EUCLEAN; 7510 goto out; 7511 } 7512 map->verified_stripes++; 7513 break; 7514 } 7515 } 7516 if (!found) { 7517 btrfs_err(fs_info, 7518 "dev extent physical offset %llu devid %llu has no corresponding chunk", 7519 physical_offset, devid); 7520 ret = -EUCLEAN; 7521 } 7522 7523 /* Make sure no dev extent is beyond device bondary */ 7524 dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true); 7525 if (!dev) { 7526 btrfs_err(fs_info, "failed to find devid %llu", devid); 7527 ret = -EUCLEAN; 7528 goto out; 7529 } 7530 7531 /* It's possible this device is a dummy for seed device */ 7532 if (dev->disk_total_bytes == 0) { 7533 dev = btrfs_find_device(fs_info->fs_devices->seed, devid, NULL, 7534 NULL, false); 7535 if (!dev) { 7536 btrfs_err(fs_info, "failed to find seed devid %llu", 7537 devid); 7538 ret = -EUCLEAN; 7539 goto out; 7540 } 7541 } 7542 7543 if (physical_offset + physical_len > dev->disk_total_bytes) { 7544 btrfs_err(fs_info, 7545 "dev extent devid %llu physical offset %llu len %llu is beyond device boundary %llu", 7546 devid, physical_offset, physical_len, 7547 dev->disk_total_bytes); 7548 ret = -EUCLEAN; 7549 goto out; 7550 } 7551 out: 7552 free_extent_map(em); 7553 return ret; 7554 } 7555 7556 static int verify_chunk_dev_extent_mapping(struct btrfs_fs_info *fs_info) 7557 { 7558 struct extent_map_tree *em_tree = &fs_info->mapping_tree; 7559 struct extent_map *em; 7560 struct rb_node *node; 7561 int ret = 0; 7562 7563 read_lock(&em_tree->lock); 7564 for (node = rb_first_cached(&em_tree->map); node; node = rb_next(node)) { 7565 em = rb_entry(node, struct extent_map, rb_node); 7566 if (em->map_lookup->num_stripes != 7567 em->map_lookup->verified_stripes) { 7568 btrfs_err(fs_info, 7569 "chunk %llu has missing dev extent, have %d expect %d", 7570 em->start, em->map_lookup->verified_stripes, 7571 em->map_lookup->num_stripes); 7572 ret = -EUCLEAN; 7573 goto out; 7574 } 7575 } 7576 out: 7577 read_unlock(&em_tree->lock); 7578 return ret; 7579 } 7580 7581 /* 7582 * Ensure that all dev extents are mapped to correct chunk, otherwise 7583 * later chunk allocation/free would cause unexpected behavior. 7584 * 7585 * NOTE: This will iterate through the whole device tree, which should be of 7586 * the same size level as the chunk tree. This slightly increases mount time. 7587 */ 7588 int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info) 7589 { 7590 struct btrfs_path *path; 7591 struct btrfs_root *root = fs_info->dev_root; 7592 struct btrfs_key key; 7593 u64 prev_devid = 0; 7594 u64 prev_dev_ext_end = 0; 7595 int ret = 0; 7596 7597 key.objectid = 1; 7598 key.type = BTRFS_DEV_EXTENT_KEY; 7599 key.offset = 0; 7600 7601 path = btrfs_alloc_path(); 7602 if (!path) 7603 return -ENOMEM; 7604 7605 path->reada = READA_FORWARD; 7606 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 7607 if (ret < 0) 7608 goto out; 7609 7610 if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { 7611 ret = btrfs_next_item(root, path); 7612 if (ret < 0) 7613 goto out; 7614 /* No dev extents at all? Not good */ 7615 if (ret > 0) { 7616 ret = -EUCLEAN; 7617 goto out; 7618 } 7619 } 7620 while (1) { 7621 struct extent_buffer *leaf = path->nodes[0]; 7622 struct btrfs_dev_extent *dext; 7623 int slot = path->slots[0]; 7624 u64 chunk_offset; 7625 u64 physical_offset; 7626 u64 physical_len; 7627 u64 devid; 7628 7629 btrfs_item_key_to_cpu(leaf, &key, slot); 7630 if (key.type != BTRFS_DEV_EXTENT_KEY) 7631 break; 7632 devid = key.objectid; 7633 physical_offset = key.offset; 7634 7635 dext = btrfs_item_ptr(leaf, slot, struct btrfs_dev_extent); 7636 chunk_offset = btrfs_dev_extent_chunk_offset(leaf, dext); 7637 physical_len = btrfs_dev_extent_length(leaf, dext); 7638 7639 /* Check if this dev extent overlaps with the previous one */ 7640 if (devid == prev_devid && physical_offset < prev_dev_ext_end) { 7641 btrfs_err(fs_info, 7642 "dev extent devid %llu physical offset %llu overlap with previous dev extent end %llu", 7643 devid, physical_offset, prev_dev_ext_end); 7644 ret = -EUCLEAN; 7645 goto out; 7646 } 7647 7648 ret = verify_one_dev_extent(fs_info, chunk_offset, devid, 7649 physical_offset, physical_len); 7650 if (ret < 0) 7651 goto out; 7652 prev_devid = devid; 7653 prev_dev_ext_end = physical_offset + physical_len; 7654 7655 ret = btrfs_next_item(root, path); 7656 if (ret < 0) 7657 goto out; 7658 if (ret > 0) { 7659 ret = 0; 7660 break; 7661 } 7662 } 7663 7664 /* Ensure all chunks have corresponding dev extents */ 7665 ret = verify_chunk_dev_extent_mapping(fs_info); 7666 out: 7667 btrfs_free_path(path); 7668 return ret; 7669 } 7670 7671 /* 7672 * Check whether the given block group or device is pinned by any inode being 7673 * used as a swapfile. 7674 */ 7675 bool btrfs_pinned_by_swapfile(struct btrfs_fs_info *fs_info, void *ptr) 7676 { 7677 struct btrfs_swapfile_pin *sp; 7678 struct rb_node *node; 7679 7680 spin_lock(&fs_info->swapfile_pins_lock); 7681 node = fs_info->swapfile_pins.rb_node; 7682 while (node) { 7683 sp = rb_entry(node, struct btrfs_swapfile_pin, node); 7684 if (ptr < sp->ptr) 7685 node = node->rb_left; 7686 else if (ptr > sp->ptr) 7687 node = node->rb_right; 7688 else 7689 break; 7690 } 7691 spin_unlock(&fs_info->swapfile_pins_lock); 7692 return node != NULL; 7693 } 7694