1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 #include <linux/sched.h> 19 #include <linux/bio.h> 20 #include <linux/slab.h> 21 #include <linux/buffer_head.h> 22 #include <linux/blkdev.h> 23 #include <linux/random.h> 24 #include <linux/iocontext.h> 25 #include <linux/capability.h> 26 #include <linux/ratelimit.h> 27 #include <linux/kthread.h> 28 #include <linux/raid/pq.h> 29 #include <linux/semaphore.h> 30 #include <asm/div64.h> 31 #include "compat.h" 32 #include "ctree.h" 33 #include "extent_map.h" 34 #include "disk-io.h" 35 #include "transaction.h" 36 #include "print-tree.h" 37 #include "volumes.h" 38 #include "raid56.h" 39 #include "async-thread.h" 40 #include "check-integrity.h" 41 #include "rcu-string.h" 42 #include "math.h" 43 #include "dev-replace.h" 44 45 static int init_first_rw_device(struct btrfs_trans_handle *trans, 46 struct btrfs_root *root, 47 struct btrfs_device *device); 48 static int btrfs_relocate_sys_chunks(struct btrfs_root *root); 49 static void __btrfs_reset_dev_stats(struct btrfs_device *dev); 50 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev); 51 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); 52 53 static DEFINE_MUTEX(uuid_mutex); 54 static LIST_HEAD(fs_uuids); 55 56 static void lock_chunks(struct btrfs_root *root) 57 { 58 mutex_lock(&root->fs_info->chunk_mutex); 59 } 60 61 static void unlock_chunks(struct btrfs_root *root) 62 { 63 mutex_unlock(&root->fs_info->chunk_mutex); 64 } 65 66 static struct btrfs_fs_devices *__alloc_fs_devices(void) 67 { 68 struct btrfs_fs_devices *fs_devs; 69 70 fs_devs = kzalloc(sizeof(*fs_devs), GFP_NOFS); 71 if (!fs_devs) 72 return ERR_PTR(-ENOMEM); 73 74 mutex_init(&fs_devs->device_list_mutex); 75 76 INIT_LIST_HEAD(&fs_devs->devices); 77 INIT_LIST_HEAD(&fs_devs->alloc_list); 78 INIT_LIST_HEAD(&fs_devs->list); 79 80 return fs_devs; 81 } 82 83 /** 84 * alloc_fs_devices - allocate struct btrfs_fs_devices 85 * @fsid: a pointer to UUID for this FS. If NULL a new UUID is 86 * generated. 87 * 88 * Return: a pointer to a new &struct btrfs_fs_devices on success; 89 * ERR_PTR() on error. Returned struct is not linked onto any lists and 90 * can be destroyed with kfree() right away. 91 */ 92 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid) 93 { 94 struct btrfs_fs_devices *fs_devs; 95 96 fs_devs = __alloc_fs_devices(); 97 if (IS_ERR(fs_devs)) 98 return fs_devs; 99 100 if (fsid) 101 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE); 102 else 103 generate_random_uuid(fs_devs->fsid); 104 105 return fs_devs; 106 } 107 108 static void free_fs_devices(struct btrfs_fs_devices *fs_devices) 109 { 110 struct btrfs_device *device; 111 WARN_ON(fs_devices->opened); 112 while (!list_empty(&fs_devices->devices)) { 113 device = list_entry(fs_devices->devices.next, 114 struct btrfs_device, dev_list); 115 list_del(&device->dev_list); 116 rcu_string_free(device->name); 117 kfree(device); 118 } 119 kfree(fs_devices); 120 } 121 122 static void btrfs_kobject_uevent(struct block_device *bdev, 123 enum kobject_action action) 124 { 125 int ret; 126 127 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 128 if (ret) 129 pr_warn("Sending event '%d' to kobject: '%s' (%p): failed\n", 130 action, 131 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 132 &disk_to_dev(bdev->bd_disk)->kobj); 133 } 134 135 void btrfs_cleanup_fs_uuids(void) 136 { 137 struct btrfs_fs_devices *fs_devices; 138 139 while (!list_empty(&fs_uuids)) { 140 fs_devices = list_entry(fs_uuids.next, 141 struct btrfs_fs_devices, list); 142 list_del(&fs_devices->list); 143 free_fs_devices(fs_devices); 144 } 145 } 146 147 static struct btrfs_device *__alloc_device(void) 148 { 149 struct btrfs_device *dev; 150 151 dev = kzalloc(sizeof(*dev), GFP_NOFS); 152 if (!dev) 153 return ERR_PTR(-ENOMEM); 154 155 INIT_LIST_HEAD(&dev->dev_list); 156 INIT_LIST_HEAD(&dev->dev_alloc_list); 157 158 spin_lock_init(&dev->io_lock); 159 160 spin_lock_init(&dev->reada_lock); 161 atomic_set(&dev->reada_in_flight, 0); 162 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_WAIT); 163 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_WAIT); 164 165 return dev; 166 } 167 168 static noinline struct btrfs_device *__find_device(struct list_head *head, 169 u64 devid, u8 *uuid) 170 { 171 struct btrfs_device *dev; 172 173 list_for_each_entry(dev, head, dev_list) { 174 if (dev->devid == devid && 175 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { 176 return dev; 177 } 178 } 179 return NULL; 180 } 181 182 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid) 183 { 184 struct btrfs_fs_devices *fs_devices; 185 186 list_for_each_entry(fs_devices, &fs_uuids, list) { 187 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) 188 return fs_devices; 189 } 190 return NULL; 191 } 192 193 static int 194 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder, 195 int flush, struct block_device **bdev, 196 struct buffer_head **bh) 197 { 198 int ret; 199 200 *bdev = blkdev_get_by_path(device_path, flags, holder); 201 202 if (IS_ERR(*bdev)) { 203 ret = PTR_ERR(*bdev); 204 printk(KERN_INFO "btrfs: open %s failed\n", device_path); 205 goto error; 206 } 207 208 if (flush) 209 filemap_write_and_wait((*bdev)->bd_inode->i_mapping); 210 ret = set_blocksize(*bdev, 4096); 211 if (ret) { 212 blkdev_put(*bdev, flags); 213 goto error; 214 } 215 invalidate_bdev(*bdev); 216 *bh = btrfs_read_dev_super(*bdev); 217 if (!*bh) { 218 ret = -EINVAL; 219 blkdev_put(*bdev, flags); 220 goto error; 221 } 222 223 return 0; 224 225 error: 226 *bdev = NULL; 227 *bh = NULL; 228 return ret; 229 } 230 231 static void requeue_list(struct btrfs_pending_bios *pending_bios, 232 struct bio *head, struct bio *tail) 233 { 234 235 struct bio *old_head; 236 237 old_head = pending_bios->head; 238 pending_bios->head = head; 239 if (pending_bios->tail) 240 tail->bi_next = old_head; 241 else 242 pending_bios->tail = tail; 243 } 244 245 /* 246 * we try to collect pending bios for a device so we don't get a large 247 * number of procs sending bios down to the same device. This greatly 248 * improves the schedulers ability to collect and merge the bios. 249 * 250 * But, it also turns into a long list of bios to process and that is sure 251 * to eventually make the worker thread block. The solution here is to 252 * make some progress and then put this work struct back at the end of 253 * the list if the block device is congested. This way, multiple devices 254 * can make progress from a single worker thread. 255 */ 256 static noinline void run_scheduled_bios(struct btrfs_device *device) 257 { 258 struct bio *pending; 259 struct backing_dev_info *bdi; 260 struct btrfs_fs_info *fs_info; 261 struct btrfs_pending_bios *pending_bios; 262 struct bio *tail; 263 struct bio *cur; 264 int again = 0; 265 unsigned long num_run; 266 unsigned long batch_run = 0; 267 unsigned long limit; 268 unsigned long last_waited = 0; 269 int force_reg = 0; 270 int sync_pending = 0; 271 struct blk_plug plug; 272 273 /* 274 * this function runs all the bios we've collected for 275 * a particular device. We don't want to wander off to 276 * another device without first sending all of these down. 277 * So, setup a plug here and finish it off before we return 278 */ 279 blk_start_plug(&plug); 280 281 bdi = blk_get_backing_dev_info(device->bdev); 282 fs_info = device->dev_root->fs_info; 283 limit = btrfs_async_submit_limit(fs_info); 284 limit = limit * 2 / 3; 285 286 loop: 287 spin_lock(&device->io_lock); 288 289 loop_lock: 290 num_run = 0; 291 292 /* take all the bios off the list at once and process them 293 * later on (without the lock held). But, remember the 294 * tail and other pointers so the bios can be properly reinserted 295 * into the list if we hit congestion 296 */ 297 if (!force_reg && device->pending_sync_bios.head) { 298 pending_bios = &device->pending_sync_bios; 299 force_reg = 1; 300 } else { 301 pending_bios = &device->pending_bios; 302 force_reg = 0; 303 } 304 305 pending = pending_bios->head; 306 tail = pending_bios->tail; 307 WARN_ON(pending && !tail); 308 309 /* 310 * if pending was null this time around, no bios need processing 311 * at all and we can stop. Otherwise it'll loop back up again 312 * and do an additional check so no bios are missed. 313 * 314 * device->running_pending is used to synchronize with the 315 * schedule_bio code. 316 */ 317 if (device->pending_sync_bios.head == NULL && 318 device->pending_bios.head == NULL) { 319 again = 0; 320 device->running_pending = 0; 321 } else { 322 again = 1; 323 device->running_pending = 1; 324 } 325 326 pending_bios->head = NULL; 327 pending_bios->tail = NULL; 328 329 spin_unlock(&device->io_lock); 330 331 while (pending) { 332 333 rmb(); 334 /* we want to work on both lists, but do more bios on the 335 * sync list than the regular list 336 */ 337 if ((num_run > 32 && 338 pending_bios != &device->pending_sync_bios && 339 device->pending_sync_bios.head) || 340 (num_run > 64 && pending_bios == &device->pending_sync_bios && 341 device->pending_bios.head)) { 342 spin_lock(&device->io_lock); 343 requeue_list(pending_bios, pending, tail); 344 goto loop_lock; 345 } 346 347 cur = pending; 348 pending = pending->bi_next; 349 cur->bi_next = NULL; 350 351 if (atomic_dec_return(&fs_info->nr_async_bios) < limit && 352 waitqueue_active(&fs_info->async_submit_wait)) 353 wake_up(&fs_info->async_submit_wait); 354 355 BUG_ON(atomic_read(&cur->bi_cnt) == 0); 356 357 /* 358 * if we're doing the sync list, record that our 359 * plug has some sync requests on it 360 * 361 * If we're doing the regular list and there are 362 * sync requests sitting around, unplug before 363 * we add more 364 */ 365 if (pending_bios == &device->pending_sync_bios) { 366 sync_pending = 1; 367 } else if (sync_pending) { 368 blk_finish_plug(&plug); 369 blk_start_plug(&plug); 370 sync_pending = 0; 371 } 372 373 btrfsic_submit_bio(cur->bi_rw, cur); 374 num_run++; 375 batch_run++; 376 if (need_resched()) 377 cond_resched(); 378 379 /* 380 * we made progress, there is more work to do and the bdi 381 * is now congested. Back off and let other work structs 382 * run instead 383 */ 384 if (pending && bdi_write_congested(bdi) && batch_run > 8 && 385 fs_info->fs_devices->open_devices > 1) { 386 struct io_context *ioc; 387 388 ioc = current->io_context; 389 390 /* 391 * the main goal here is that we don't want to 392 * block if we're going to be able to submit 393 * more requests without blocking. 394 * 395 * This code does two great things, it pokes into 396 * the elevator code from a filesystem _and_ 397 * it makes assumptions about how batching works. 398 */ 399 if (ioc && ioc->nr_batch_requests > 0 && 400 time_before(jiffies, ioc->last_waited + HZ/50UL) && 401 (last_waited == 0 || 402 ioc->last_waited == last_waited)) { 403 /* 404 * we want to go through our batch of 405 * requests and stop. So, we copy out 406 * the ioc->last_waited time and test 407 * against it before looping 408 */ 409 last_waited = ioc->last_waited; 410 if (need_resched()) 411 cond_resched(); 412 continue; 413 } 414 spin_lock(&device->io_lock); 415 requeue_list(pending_bios, pending, tail); 416 device->running_pending = 1; 417 418 spin_unlock(&device->io_lock); 419 btrfs_requeue_work(&device->work); 420 goto done; 421 } 422 /* unplug every 64 requests just for good measure */ 423 if (batch_run % 64 == 0) { 424 blk_finish_plug(&plug); 425 blk_start_plug(&plug); 426 sync_pending = 0; 427 } 428 } 429 430 cond_resched(); 431 if (again) 432 goto loop; 433 434 spin_lock(&device->io_lock); 435 if (device->pending_bios.head || device->pending_sync_bios.head) 436 goto loop_lock; 437 spin_unlock(&device->io_lock); 438 439 done: 440 blk_finish_plug(&plug); 441 } 442 443 static void pending_bios_fn(struct btrfs_work *work) 444 { 445 struct btrfs_device *device; 446 447 device = container_of(work, struct btrfs_device, work); 448 run_scheduled_bios(device); 449 } 450 451 static noinline int device_list_add(const char *path, 452 struct btrfs_super_block *disk_super, 453 u64 devid, struct btrfs_fs_devices **fs_devices_ret) 454 { 455 struct btrfs_device *device; 456 struct btrfs_fs_devices *fs_devices; 457 struct rcu_string *name; 458 u64 found_transid = btrfs_super_generation(disk_super); 459 460 fs_devices = find_fsid(disk_super->fsid); 461 if (!fs_devices) { 462 fs_devices = alloc_fs_devices(disk_super->fsid); 463 if (IS_ERR(fs_devices)) 464 return PTR_ERR(fs_devices); 465 466 list_add(&fs_devices->list, &fs_uuids); 467 fs_devices->latest_devid = devid; 468 fs_devices->latest_trans = found_transid; 469 470 device = NULL; 471 } else { 472 device = __find_device(&fs_devices->devices, devid, 473 disk_super->dev_item.uuid); 474 } 475 if (!device) { 476 if (fs_devices->opened) 477 return -EBUSY; 478 479 device = btrfs_alloc_device(NULL, &devid, 480 disk_super->dev_item.uuid); 481 if (IS_ERR(device)) { 482 /* we can safely leave the fs_devices entry around */ 483 return PTR_ERR(device); 484 } 485 486 name = rcu_string_strdup(path, GFP_NOFS); 487 if (!name) { 488 kfree(device); 489 return -ENOMEM; 490 } 491 rcu_assign_pointer(device->name, name); 492 493 mutex_lock(&fs_devices->device_list_mutex); 494 list_add_rcu(&device->dev_list, &fs_devices->devices); 495 fs_devices->num_devices++; 496 mutex_unlock(&fs_devices->device_list_mutex); 497 498 device->fs_devices = fs_devices; 499 } else if (!device->name || strcmp(device->name->str, path)) { 500 name = rcu_string_strdup(path, GFP_NOFS); 501 if (!name) 502 return -ENOMEM; 503 rcu_string_free(device->name); 504 rcu_assign_pointer(device->name, name); 505 if (device->missing) { 506 fs_devices->missing_devices--; 507 device->missing = 0; 508 } 509 } 510 511 if (found_transid > fs_devices->latest_trans) { 512 fs_devices->latest_devid = devid; 513 fs_devices->latest_trans = found_transid; 514 } 515 *fs_devices_ret = fs_devices; 516 return 0; 517 } 518 519 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) 520 { 521 struct btrfs_fs_devices *fs_devices; 522 struct btrfs_device *device; 523 struct btrfs_device *orig_dev; 524 525 fs_devices = alloc_fs_devices(orig->fsid); 526 if (IS_ERR(fs_devices)) 527 return fs_devices; 528 529 fs_devices->latest_devid = orig->latest_devid; 530 fs_devices->latest_trans = orig->latest_trans; 531 fs_devices->total_devices = orig->total_devices; 532 533 /* We have held the volume lock, it is safe to get the devices. */ 534 list_for_each_entry(orig_dev, &orig->devices, dev_list) { 535 struct rcu_string *name; 536 537 device = btrfs_alloc_device(NULL, &orig_dev->devid, 538 orig_dev->uuid); 539 if (IS_ERR(device)) 540 goto error; 541 542 /* 543 * This is ok to do without rcu read locked because we hold the 544 * uuid mutex so nothing we touch in here is going to disappear. 545 */ 546 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS); 547 if (!name) { 548 kfree(device); 549 goto error; 550 } 551 rcu_assign_pointer(device->name, name); 552 553 list_add(&device->dev_list, &fs_devices->devices); 554 device->fs_devices = fs_devices; 555 fs_devices->num_devices++; 556 } 557 return fs_devices; 558 error: 559 free_fs_devices(fs_devices); 560 return ERR_PTR(-ENOMEM); 561 } 562 563 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info, 564 struct btrfs_fs_devices *fs_devices, int step) 565 { 566 struct btrfs_device *device, *next; 567 568 struct block_device *latest_bdev = NULL; 569 u64 latest_devid = 0; 570 u64 latest_transid = 0; 571 572 mutex_lock(&uuid_mutex); 573 again: 574 /* This is the initialized path, it is safe to release the devices. */ 575 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 576 if (device->in_fs_metadata) { 577 if (!device->is_tgtdev_for_dev_replace && 578 (!latest_transid || 579 device->generation > latest_transid)) { 580 latest_devid = device->devid; 581 latest_transid = device->generation; 582 latest_bdev = device->bdev; 583 } 584 continue; 585 } 586 587 if (device->devid == BTRFS_DEV_REPLACE_DEVID) { 588 /* 589 * In the first step, keep the device which has 590 * the correct fsid and the devid that is used 591 * for the dev_replace procedure. 592 * In the second step, the dev_replace state is 593 * read from the device tree and it is known 594 * whether the procedure is really active or 595 * not, which means whether this device is 596 * used or whether it should be removed. 597 */ 598 if (step == 0 || device->is_tgtdev_for_dev_replace) { 599 continue; 600 } 601 } 602 if (device->bdev) { 603 blkdev_put(device->bdev, device->mode); 604 device->bdev = NULL; 605 fs_devices->open_devices--; 606 } 607 if (device->writeable) { 608 list_del_init(&device->dev_alloc_list); 609 device->writeable = 0; 610 if (!device->is_tgtdev_for_dev_replace) 611 fs_devices->rw_devices--; 612 } 613 list_del_init(&device->dev_list); 614 fs_devices->num_devices--; 615 rcu_string_free(device->name); 616 kfree(device); 617 } 618 619 if (fs_devices->seed) { 620 fs_devices = fs_devices->seed; 621 goto again; 622 } 623 624 fs_devices->latest_bdev = latest_bdev; 625 fs_devices->latest_devid = latest_devid; 626 fs_devices->latest_trans = latest_transid; 627 628 mutex_unlock(&uuid_mutex); 629 } 630 631 static void __free_device(struct work_struct *work) 632 { 633 struct btrfs_device *device; 634 635 device = container_of(work, struct btrfs_device, rcu_work); 636 637 if (device->bdev) 638 blkdev_put(device->bdev, device->mode); 639 640 rcu_string_free(device->name); 641 kfree(device); 642 } 643 644 static void free_device(struct rcu_head *head) 645 { 646 struct btrfs_device *device; 647 648 device = container_of(head, struct btrfs_device, rcu); 649 650 INIT_WORK(&device->rcu_work, __free_device); 651 schedule_work(&device->rcu_work); 652 } 653 654 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 655 { 656 struct btrfs_device *device; 657 658 if (--fs_devices->opened > 0) 659 return 0; 660 661 mutex_lock(&fs_devices->device_list_mutex); 662 list_for_each_entry(device, &fs_devices->devices, dev_list) { 663 struct btrfs_device *new_device; 664 struct rcu_string *name; 665 666 if (device->bdev) 667 fs_devices->open_devices--; 668 669 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 670 list_del_init(&device->dev_alloc_list); 671 fs_devices->rw_devices--; 672 } 673 674 if (device->can_discard) 675 fs_devices->num_can_discard--; 676 if (device->missing) 677 fs_devices->missing_devices--; 678 679 new_device = btrfs_alloc_device(NULL, &device->devid, 680 device->uuid); 681 BUG_ON(IS_ERR(new_device)); /* -ENOMEM */ 682 683 /* Safe because we are under uuid_mutex */ 684 if (device->name) { 685 name = rcu_string_strdup(device->name->str, GFP_NOFS); 686 BUG_ON(!name); /* -ENOMEM */ 687 rcu_assign_pointer(new_device->name, name); 688 } 689 690 list_replace_rcu(&device->dev_list, &new_device->dev_list); 691 new_device->fs_devices = device->fs_devices; 692 693 call_rcu(&device->rcu, free_device); 694 } 695 mutex_unlock(&fs_devices->device_list_mutex); 696 697 WARN_ON(fs_devices->open_devices); 698 WARN_ON(fs_devices->rw_devices); 699 fs_devices->opened = 0; 700 fs_devices->seeding = 0; 701 702 return 0; 703 } 704 705 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 706 { 707 struct btrfs_fs_devices *seed_devices = NULL; 708 int ret; 709 710 mutex_lock(&uuid_mutex); 711 ret = __btrfs_close_devices(fs_devices); 712 if (!fs_devices->opened) { 713 seed_devices = fs_devices->seed; 714 fs_devices->seed = NULL; 715 } 716 mutex_unlock(&uuid_mutex); 717 718 while (seed_devices) { 719 fs_devices = seed_devices; 720 seed_devices = fs_devices->seed; 721 __btrfs_close_devices(fs_devices); 722 free_fs_devices(fs_devices); 723 } 724 /* 725 * Wait for rcu kworkers under __btrfs_close_devices 726 * to finish all blkdev_puts so device is really 727 * free when umount is done. 728 */ 729 rcu_barrier(); 730 return ret; 731 } 732 733 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 734 fmode_t flags, void *holder) 735 { 736 struct request_queue *q; 737 struct block_device *bdev; 738 struct list_head *head = &fs_devices->devices; 739 struct btrfs_device *device; 740 struct block_device *latest_bdev = NULL; 741 struct buffer_head *bh; 742 struct btrfs_super_block *disk_super; 743 u64 latest_devid = 0; 744 u64 latest_transid = 0; 745 u64 devid; 746 int seeding = 1; 747 int ret = 0; 748 749 flags |= FMODE_EXCL; 750 751 list_for_each_entry(device, head, dev_list) { 752 if (device->bdev) 753 continue; 754 if (!device->name) 755 continue; 756 757 /* Just open everything we can; ignore failures here */ 758 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, 759 &bdev, &bh)) 760 continue; 761 762 disk_super = (struct btrfs_super_block *)bh->b_data; 763 devid = btrfs_stack_device_id(&disk_super->dev_item); 764 if (devid != device->devid) 765 goto error_brelse; 766 767 if (memcmp(device->uuid, disk_super->dev_item.uuid, 768 BTRFS_UUID_SIZE)) 769 goto error_brelse; 770 771 device->generation = btrfs_super_generation(disk_super); 772 if (!latest_transid || device->generation > latest_transid) { 773 latest_devid = devid; 774 latest_transid = device->generation; 775 latest_bdev = bdev; 776 } 777 778 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { 779 device->writeable = 0; 780 } else { 781 device->writeable = !bdev_read_only(bdev); 782 seeding = 0; 783 } 784 785 q = bdev_get_queue(bdev); 786 if (blk_queue_discard(q)) { 787 device->can_discard = 1; 788 fs_devices->num_can_discard++; 789 } 790 791 device->bdev = bdev; 792 device->in_fs_metadata = 0; 793 device->mode = flags; 794 795 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 796 fs_devices->rotating = 1; 797 798 fs_devices->open_devices++; 799 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 800 fs_devices->rw_devices++; 801 list_add(&device->dev_alloc_list, 802 &fs_devices->alloc_list); 803 } 804 brelse(bh); 805 continue; 806 807 error_brelse: 808 brelse(bh); 809 blkdev_put(bdev, flags); 810 continue; 811 } 812 if (fs_devices->open_devices == 0) { 813 ret = -EINVAL; 814 goto out; 815 } 816 fs_devices->seeding = seeding; 817 fs_devices->opened = 1; 818 fs_devices->latest_bdev = latest_bdev; 819 fs_devices->latest_devid = latest_devid; 820 fs_devices->latest_trans = latest_transid; 821 fs_devices->total_rw_bytes = 0; 822 out: 823 return ret; 824 } 825 826 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 827 fmode_t flags, void *holder) 828 { 829 int ret; 830 831 mutex_lock(&uuid_mutex); 832 if (fs_devices->opened) { 833 fs_devices->opened++; 834 ret = 0; 835 } else { 836 ret = __btrfs_open_devices(fs_devices, flags, holder); 837 } 838 mutex_unlock(&uuid_mutex); 839 return ret; 840 } 841 842 /* 843 * Look for a btrfs signature on a device. This may be called out of the mount path 844 * and we are not allowed to call set_blocksize during the scan. The superblock 845 * is read via pagecache 846 */ 847 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, 848 struct btrfs_fs_devices **fs_devices_ret) 849 { 850 struct btrfs_super_block *disk_super; 851 struct block_device *bdev; 852 struct page *page; 853 void *p; 854 int ret = -EINVAL; 855 u64 devid; 856 u64 transid; 857 u64 total_devices; 858 u64 bytenr; 859 pgoff_t index; 860 861 /* 862 * we would like to check all the supers, but that would make 863 * a btrfs mount succeed after a mkfs from a different FS. 864 * So, we need to add a special mount option to scan for 865 * later supers, using BTRFS_SUPER_MIRROR_MAX instead 866 */ 867 bytenr = btrfs_sb_offset(0); 868 flags |= FMODE_EXCL; 869 mutex_lock(&uuid_mutex); 870 871 bdev = blkdev_get_by_path(path, flags, holder); 872 873 if (IS_ERR(bdev)) { 874 ret = PTR_ERR(bdev); 875 goto error; 876 } 877 878 /* make sure our super fits in the device */ 879 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode)) 880 goto error_bdev_put; 881 882 /* make sure our super fits in the page */ 883 if (sizeof(*disk_super) > PAGE_CACHE_SIZE) 884 goto error_bdev_put; 885 886 /* make sure our super doesn't straddle pages on disk */ 887 index = bytenr >> PAGE_CACHE_SHIFT; 888 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index) 889 goto error_bdev_put; 890 891 /* pull in the page with our super */ 892 page = read_cache_page_gfp(bdev->bd_inode->i_mapping, 893 index, GFP_NOFS); 894 895 if (IS_ERR_OR_NULL(page)) 896 goto error_bdev_put; 897 898 p = kmap(page); 899 900 /* align our pointer to the offset of the super block */ 901 disk_super = p + (bytenr & ~PAGE_CACHE_MASK); 902 903 if (btrfs_super_bytenr(disk_super) != bytenr || 904 btrfs_super_magic(disk_super) != BTRFS_MAGIC) 905 goto error_unmap; 906 907 devid = btrfs_stack_device_id(&disk_super->dev_item); 908 transid = btrfs_super_generation(disk_super); 909 total_devices = btrfs_super_num_devices(disk_super); 910 911 if (disk_super->label[0]) { 912 if (disk_super->label[BTRFS_LABEL_SIZE - 1]) 913 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0'; 914 printk(KERN_INFO "device label %s ", disk_super->label); 915 } else { 916 printk(KERN_INFO "device fsid %pU ", disk_super->fsid); 917 } 918 919 printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path); 920 921 ret = device_list_add(path, disk_super, devid, fs_devices_ret); 922 if (!ret && fs_devices_ret) 923 (*fs_devices_ret)->total_devices = total_devices; 924 925 error_unmap: 926 kunmap(page); 927 page_cache_release(page); 928 929 error_bdev_put: 930 blkdev_put(bdev, flags); 931 error: 932 mutex_unlock(&uuid_mutex); 933 return ret; 934 } 935 936 /* helper to account the used device space in the range */ 937 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, 938 u64 end, u64 *length) 939 { 940 struct btrfs_key key; 941 struct btrfs_root *root = device->dev_root; 942 struct btrfs_dev_extent *dev_extent; 943 struct btrfs_path *path; 944 u64 extent_end; 945 int ret; 946 int slot; 947 struct extent_buffer *l; 948 949 *length = 0; 950 951 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace) 952 return 0; 953 954 path = btrfs_alloc_path(); 955 if (!path) 956 return -ENOMEM; 957 path->reada = 2; 958 959 key.objectid = device->devid; 960 key.offset = start; 961 key.type = BTRFS_DEV_EXTENT_KEY; 962 963 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 964 if (ret < 0) 965 goto out; 966 if (ret > 0) { 967 ret = btrfs_previous_item(root, path, key.objectid, key.type); 968 if (ret < 0) 969 goto out; 970 } 971 972 while (1) { 973 l = path->nodes[0]; 974 slot = path->slots[0]; 975 if (slot >= btrfs_header_nritems(l)) { 976 ret = btrfs_next_leaf(root, path); 977 if (ret == 0) 978 continue; 979 if (ret < 0) 980 goto out; 981 982 break; 983 } 984 btrfs_item_key_to_cpu(l, &key, slot); 985 986 if (key.objectid < device->devid) 987 goto next; 988 989 if (key.objectid > device->devid) 990 break; 991 992 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 993 goto next; 994 995 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 996 extent_end = key.offset + btrfs_dev_extent_length(l, 997 dev_extent); 998 if (key.offset <= start && extent_end > end) { 999 *length = end - start + 1; 1000 break; 1001 } else if (key.offset <= start && extent_end > start) 1002 *length += extent_end - start; 1003 else if (key.offset > start && extent_end <= end) 1004 *length += extent_end - key.offset; 1005 else if (key.offset > start && key.offset <= end) { 1006 *length += end - key.offset + 1; 1007 break; 1008 } else if (key.offset > end) 1009 break; 1010 1011 next: 1012 path->slots[0]++; 1013 } 1014 ret = 0; 1015 out: 1016 btrfs_free_path(path); 1017 return ret; 1018 } 1019 1020 static int contains_pending_extent(struct btrfs_trans_handle *trans, 1021 struct btrfs_device *device, 1022 u64 *start, u64 len) 1023 { 1024 struct extent_map *em; 1025 int ret = 0; 1026 1027 list_for_each_entry(em, &trans->transaction->pending_chunks, list) { 1028 struct map_lookup *map; 1029 int i; 1030 1031 map = (struct map_lookup *)em->bdev; 1032 for (i = 0; i < map->num_stripes; i++) { 1033 if (map->stripes[i].dev != device) 1034 continue; 1035 if (map->stripes[i].physical >= *start + len || 1036 map->stripes[i].physical + em->orig_block_len <= 1037 *start) 1038 continue; 1039 *start = map->stripes[i].physical + 1040 em->orig_block_len; 1041 ret = 1; 1042 } 1043 } 1044 1045 return ret; 1046 } 1047 1048 1049 /* 1050 * find_free_dev_extent - find free space in the specified device 1051 * @device: the device which we search the free space in 1052 * @num_bytes: the size of the free space that we need 1053 * @start: store the start of the free space. 1054 * @len: the size of the free space. that we find, or the size of the max 1055 * free space if we don't find suitable free space 1056 * 1057 * this uses a pretty simple search, the expectation is that it is 1058 * called very infrequently and that a given device has a small number 1059 * of extents 1060 * 1061 * @start is used to store the start of the free space if we find. But if we 1062 * don't find suitable free space, it will be used to store the start position 1063 * of the max free space. 1064 * 1065 * @len is used to store the size of the free space that we find. 1066 * But if we don't find suitable free space, it is used to store the size of 1067 * the max free space. 1068 */ 1069 int find_free_dev_extent(struct btrfs_trans_handle *trans, 1070 struct btrfs_device *device, u64 num_bytes, 1071 u64 *start, u64 *len) 1072 { 1073 struct btrfs_key key; 1074 struct btrfs_root *root = device->dev_root; 1075 struct btrfs_dev_extent *dev_extent; 1076 struct btrfs_path *path; 1077 u64 hole_size; 1078 u64 max_hole_start; 1079 u64 max_hole_size; 1080 u64 extent_end; 1081 u64 search_start; 1082 u64 search_end = device->total_bytes; 1083 int ret; 1084 int slot; 1085 struct extent_buffer *l; 1086 1087 /* FIXME use last free of some kind */ 1088 1089 /* we don't want to overwrite the superblock on the drive, 1090 * so we make sure to start at an offset of at least 1MB 1091 */ 1092 search_start = max(root->fs_info->alloc_start, 1024ull * 1024); 1093 1094 path = btrfs_alloc_path(); 1095 if (!path) 1096 return -ENOMEM; 1097 again: 1098 max_hole_start = search_start; 1099 max_hole_size = 0; 1100 hole_size = 0; 1101 1102 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) { 1103 ret = -ENOSPC; 1104 goto out; 1105 } 1106 1107 path->reada = 2; 1108 path->search_commit_root = 1; 1109 path->skip_locking = 1; 1110 1111 key.objectid = device->devid; 1112 key.offset = search_start; 1113 key.type = BTRFS_DEV_EXTENT_KEY; 1114 1115 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1116 if (ret < 0) 1117 goto out; 1118 if (ret > 0) { 1119 ret = btrfs_previous_item(root, path, key.objectid, key.type); 1120 if (ret < 0) 1121 goto out; 1122 } 1123 1124 while (1) { 1125 l = path->nodes[0]; 1126 slot = path->slots[0]; 1127 if (slot >= btrfs_header_nritems(l)) { 1128 ret = btrfs_next_leaf(root, path); 1129 if (ret == 0) 1130 continue; 1131 if (ret < 0) 1132 goto out; 1133 1134 break; 1135 } 1136 btrfs_item_key_to_cpu(l, &key, slot); 1137 1138 if (key.objectid < device->devid) 1139 goto next; 1140 1141 if (key.objectid > device->devid) 1142 break; 1143 1144 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 1145 goto next; 1146 1147 if (key.offset > search_start) { 1148 hole_size = key.offset - search_start; 1149 1150 /* 1151 * Have to check before we set max_hole_start, otherwise 1152 * we could end up sending back this offset anyway. 1153 */ 1154 if (contains_pending_extent(trans, device, 1155 &search_start, 1156 hole_size)) 1157 hole_size = 0; 1158 1159 if (hole_size > max_hole_size) { 1160 max_hole_start = search_start; 1161 max_hole_size = hole_size; 1162 } 1163 1164 /* 1165 * If this free space is greater than which we need, 1166 * it must be the max free space that we have found 1167 * until now, so max_hole_start must point to the start 1168 * of this free space and the length of this free space 1169 * is stored in max_hole_size. Thus, we return 1170 * max_hole_start and max_hole_size and go back to the 1171 * caller. 1172 */ 1173 if (hole_size >= num_bytes) { 1174 ret = 0; 1175 goto out; 1176 } 1177 } 1178 1179 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 1180 extent_end = key.offset + btrfs_dev_extent_length(l, 1181 dev_extent); 1182 if (extent_end > search_start) 1183 search_start = extent_end; 1184 next: 1185 path->slots[0]++; 1186 cond_resched(); 1187 } 1188 1189 /* 1190 * At this point, search_start should be the end of 1191 * allocated dev extents, and when shrinking the device, 1192 * search_end may be smaller than search_start. 1193 */ 1194 if (search_end > search_start) 1195 hole_size = search_end - search_start; 1196 1197 if (hole_size > max_hole_size) { 1198 max_hole_start = search_start; 1199 max_hole_size = hole_size; 1200 } 1201 1202 if (contains_pending_extent(trans, device, &search_start, hole_size)) { 1203 btrfs_release_path(path); 1204 goto again; 1205 } 1206 1207 /* See above. */ 1208 if (hole_size < num_bytes) 1209 ret = -ENOSPC; 1210 else 1211 ret = 0; 1212 1213 out: 1214 btrfs_free_path(path); 1215 *start = max_hole_start; 1216 if (len) 1217 *len = max_hole_size; 1218 return ret; 1219 } 1220 1221 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, 1222 struct btrfs_device *device, 1223 u64 start) 1224 { 1225 int ret; 1226 struct btrfs_path *path; 1227 struct btrfs_root *root = device->dev_root; 1228 struct btrfs_key key; 1229 struct btrfs_key found_key; 1230 struct extent_buffer *leaf = NULL; 1231 struct btrfs_dev_extent *extent = NULL; 1232 1233 path = btrfs_alloc_path(); 1234 if (!path) 1235 return -ENOMEM; 1236 1237 key.objectid = device->devid; 1238 key.offset = start; 1239 key.type = BTRFS_DEV_EXTENT_KEY; 1240 again: 1241 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1242 if (ret > 0) { 1243 ret = btrfs_previous_item(root, path, key.objectid, 1244 BTRFS_DEV_EXTENT_KEY); 1245 if (ret) 1246 goto out; 1247 leaf = path->nodes[0]; 1248 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1249 extent = btrfs_item_ptr(leaf, path->slots[0], 1250 struct btrfs_dev_extent); 1251 BUG_ON(found_key.offset > start || found_key.offset + 1252 btrfs_dev_extent_length(leaf, extent) < start); 1253 key = found_key; 1254 btrfs_release_path(path); 1255 goto again; 1256 } else if (ret == 0) { 1257 leaf = path->nodes[0]; 1258 extent = btrfs_item_ptr(leaf, path->slots[0], 1259 struct btrfs_dev_extent); 1260 } else { 1261 btrfs_error(root->fs_info, ret, "Slot search failed"); 1262 goto out; 1263 } 1264 1265 if (device->bytes_used > 0) { 1266 u64 len = btrfs_dev_extent_length(leaf, extent); 1267 device->bytes_used -= len; 1268 spin_lock(&root->fs_info->free_chunk_lock); 1269 root->fs_info->free_chunk_space += len; 1270 spin_unlock(&root->fs_info->free_chunk_lock); 1271 } 1272 ret = btrfs_del_item(trans, root, path); 1273 if (ret) { 1274 btrfs_error(root->fs_info, ret, 1275 "Failed to remove dev extent item"); 1276 } 1277 out: 1278 btrfs_free_path(path); 1279 return ret; 1280 } 1281 1282 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, 1283 struct btrfs_device *device, 1284 u64 chunk_tree, u64 chunk_objectid, 1285 u64 chunk_offset, u64 start, u64 num_bytes) 1286 { 1287 int ret; 1288 struct btrfs_path *path; 1289 struct btrfs_root *root = device->dev_root; 1290 struct btrfs_dev_extent *extent; 1291 struct extent_buffer *leaf; 1292 struct btrfs_key key; 1293 1294 WARN_ON(!device->in_fs_metadata); 1295 WARN_ON(device->is_tgtdev_for_dev_replace); 1296 path = btrfs_alloc_path(); 1297 if (!path) 1298 return -ENOMEM; 1299 1300 key.objectid = device->devid; 1301 key.offset = start; 1302 key.type = BTRFS_DEV_EXTENT_KEY; 1303 ret = btrfs_insert_empty_item(trans, root, path, &key, 1304 sizeof(*extent)); 1305 if (ret) 1306 goto out; 1307 1308 leaf = path->nodes[0]; 1309 extent = btrfs_item_ptr(leaf, path->slots[0], 1310 struct btrfs_dev_extent); 1311 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree); 1312 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid); 1313 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); 1314 1315 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 1316 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE); 1317 1318 btrfs_set_dev_extent_length(leaf, extent, num_bytes); 1319 btrfs_mark_buffer_dirty(leaf); 1320 out: 1321 btrfs_free_path(path); 1322 return ret; 1323 } 1324 1325 static u64 find_next_chunk(struct btrfs_fs_info *fs_info) 1326 { 1327 struct extent_map_tree *em_tree; 1328 struct extent_map *em; 1329 struct rb_node *n; 1330 u64 ret = 0; 1331 1332 em_tree = &fs_info->mapping_tree.map_tree; 1333 read_lock(&em_tree->lock); 1334 n = rb_last(&em_tree->map); 1335 if (n) { 1336 em = rb_entry(n, struct extent_map, rb_node); 1337 ret = em->start + em->len; 1338 } 1339 read_unlock(&em_tree->lock); 1340 1341 return ret; 1342 } 1343 1344 static noinline int find_next_devid(struct btrfs_fs_info *fs_info, 1345 u64 *devid_ret) 1346 { 1347 int ret; 1348 struct btrfs_key key; 1349 struct btrfs_key found_key; 1350 struct btrfs_path *path; 1351 1352 path = btrfs_alloc_path(); 1353 if (!path) 1354 return -ENOMEM; 1355 1356 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1357 key.type = BTRFS_DEV_ITEM_KEY; 1358 key.offset = (u64)-1; 1359 1360 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0); 1361 if (ret < 0) 1362 goto error; 1363 1364 BUG_ON(ret == 0); /* Corruption */ 1365 1366 ret = btrfs_previous_item(fs_info->chunk_root, path, 1367 BTRFS_DEV_ITEMS_OBJECTID, 1368 BTRFS_DEV_ITEM_KEY); 1369 if (ret) { 1370 *devid_ret = 1; 1371 } else { 1372 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1373 path->slots[0]); 1374 *devid_ret = found_key.offset + 1; 1375 } 1376 ret = 0; 1377 error: 1378 btrfs_free_path(path); 1379 return ret; 1380 } 1381 1382 /* 1383 * the device information is stored in the chunk root 1384 * the btrfs_device struct should be fully filled in 1385 */ 1386 static int btrfs_add_device(struct btrfs_trans_handle *trans, 1387 struct btrfs_root *root, 1388 struct btrfs_device *device) 1389 { 1390 int ret; 1391 struct btrfs_path *path; 1392 struct btrfs_dev_item *dev_item; 1393 struct extent_buffer *leaf; 1394 struct btrfs_key key; 1395 unsigned long ptr; 1396 1397 root = root->fs_info->chunk_root; 1398 1399 path = btrfs_alloc_path(); 1400 if (!path) 1401 return -ENOMEM; 1402 1403 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1404 key.type = BTRFS_DEV_ITEM_KEY; 1405 key.offset = device->devid; 1406 1407 ret = btrfs_insert_empty_item(trans, root, path, &key, 1408 sizeof(*dev_item)); 1409 if (ret) 1410 goto out; 1411 1412 leaf = path->nodes[0]; 1413 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 1414 1415 btrfs_set_device_id(leaf, dev_item, device->devid); 1416 btrfs_set_device_generation(leaf, dev_item, 0); 1417 btrfs_set_device_type(leaf, dev_item, device->type); 1418 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 1419 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 1420 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 1421 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); 1422 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 1423 btrfs_set_device_group(leaf, dev_item, 0); 1424 btrfs_set_device_seek_speed(leaf, dev_item, 0); 1425 btrfs_set_device_bandwidth(leaf, dev_item, 0); 1426 btrfs_set_device_start_offset(leaf, dev_item, 0); 1427 1428 ptr = btrfs_device_uuid(dev_item); 1429 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 1430 ptr = btrfs_device_fsid(dev_item); 1431 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE); 1432 btrfs_mark_buffer_dirty(leaf); 1433 1434 ret = 0; 1435 out: 1436 btrfs_free_path(path); 1437 return ret; 1438 } 1439 1440 static int btrfs_rm_dev_item(struct btrfs_root *root, 1441 struct btrfs_device *device) 1442 { 1443 int ret; 1444 struct btrfs_path *path; 1445 struct btrfs_key key; 1446 struct btrfs_trans_handle *trans; 1447 1448 root = root->fs_info->chunk_root; 1449 1450 path = btrfs_alloc_path(); 1451 if (!path) 1452 return -ENOMEM; 1453 1454 trans = btrfs_start_transaction(root, 0); 1455 if (IS_ERR(trans)) { 1456 btrfs_free_path(path); 1457 return PTR_ERR(trans); 1458 } 1459 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1460 key.type = BTRFS_DEV_ITEM_KEY; 1461 key.offset = device->devid; 1462 lock_chunks(root); 1463 1464 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1465 if (ret < 0) 1466 goto out; 1467 1468 if (ret > 0) { 1469 ret = -ENOENT; 1470 goto out; 1471 } 1472 1473 ret = btrfs_del_item(trans, root, path); 1474 if (ret) 1475 goto out; 1476 out: 1477 btrfs_free_path(path); 1478 unlock_chunks(root); 1479 btrfs_commit_transaction(trans, root); 1480 return ret; 1481 } 1482 1483 int btrfs_rm_device(struct btrfs_root *root, char *device_path) 1484 { 1485 struct btrfs_device *device; 1486 struct btrfs_device *next_device; 1487 struct block_device *bdev; 1488 struct buffer_head *bh = NULL; 1489 struct btrfs_super_block *disk_super; 1490 struct btrfs_fs_devices *cur_devices; 1491 u64 all_avail; 1492 u64 devid; 1493 u64 num_devices; 1494 u8 *dev_uuid; 1495 unsigned seq; 1496 int ret = 0; 1497 bool clear_super = false; 1498 1499 mutex_lock(&uuid_mutex); 1500 1501 do { 1502 seq = read_seqbegin(&root->fs_info->profiles_lock); 1503 1504 all_avail = root->fs_info->avail_data_alloc_bits | 1505 root->fs_info->avail_system_alloc_bits | 1506 root->fs_info->avail_metadata_alloc_bits; 1507 } while (read_seqretry(&root->fs_info->profiles_lock, seq)); 1508 1509 num_devices = root->fs_info->fs_devices->num_devices; 1510 btrfs_dev_replace_lock(&root->fs_info->dev_replace); 1511 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) { 1512 WARN_ON(num_devices < 1); 1513 num_devices--; 1514 } 1515 btrfs_dev_replace_unlock(&root->fs_info->dev_replace); 1516 1517 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) { 1518 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET; 1519 goto out; 1520 } 1521 1522 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) { 1523 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET; 1524 goto out; 1525 } 1526 1527 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) && 1528 root->fs_info->fs_devices->rw_devices <= 2) { 1529 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET; 1530 goto out; 1531 } 1532 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) && 1533 root->fs_info->fs_devices->rw_devices <= 3) { 1534 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET; 1535 goto out; 1536 } 1537 1538 if (strcmp(device_path, "missing") == 0) { 1539 struct list_head *devices; 1540 struct btrfs_device *tmp; 1541 1542 device = NULL; 1543 devices = &root->fs_info->fs_devices->devices; 1544 /* 1545 * It is safe to read the devices since the volume_mutex 1546 * is held. 1547 */ 1548 list_for_each_entry(tmp, devices, dev_list) { 1549 if (tmp->in_fs_metadata && 1550 !tmp->is_tgtdev_for_dev_replace && 1551 !tmp->bdev) { 1552 device = tmp; 1553 break; 1554 } 1555 } 1556 bdev = NULL; 1557 bh = NULL; 1558 disk_super = NULL; 1559 if (!device) { 1560 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND; 1561 goto out; 1562 } 1563 } else { 1564 ret = btrfs_get_bdev_and_sb(device_path, 1565 FMODE_WRITE | FMODE_EXCL, 1566 root->fs_info->bdev_holder, 0, 1567 &bdev, &bh); 1568 if (ret) 1569 goto out; 1570 disk_super = (struct btrfs_super_block *)bh->b_data; 1571 devid = btrfs_stack_device_id(&disk_super->dev_item); 1572 dev_uuid = disk_super->dev_item.uuid; 1573 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1574 disk_super->fsid); 1575 if (!device) { 1576 ret = -ENOENT; 1577 goto error_brelse; 1578 } 1579 } 1580 1581 if (device->is_tgtdev_for_dev_replace) { 1582 ret = BTRFS_ERROR_DEV_TGT_REPLACE; 1583 goto error_brelse; 1584 } 1585 1586 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) { 1587 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE; 1588 goto error_brelse; 1589 } 1590 1591 if (device->writeable) { 1592 lock_chunks(root); 1593 list_del_init(&device->dev_alloc_list); 1594 unlock_chunks(root); 1595 root->fs_info->fs_devices->rw_devices--; 1596 clear_super = true; 1597 } 1598 1599 mutex_unlock(&uuid_mutex); 1600 ret = btrfs_shrink_device(device, 0); 1601 mutex_lock(&uuid_mutex); 1602 if (ret) 1603 goto error_undo; 1604 1605 /* 1606 * TODO: the superblock still includes this device in its num_devices 1607 * counter although write_all_supers() is not locked out. This 1608 * could give a filesystem state which requires a degraded mount. 1609 */ 1610 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); 1611 if (ret) 1612 goto error_undo; 1613 1614 spin_lock(&root->fs_info->free_chunk_lock); 1615 root->fs_info->free_chunk_space = device->total_bytes - 1616 device->bytes_used; 1617 spin_unlock(&root->fs_info->free_chunk_lock); 1618 1619 device->in_fs_metadata = 0; 1620 btrfs_scrub_cancel_dev(root->fs_info, device); 1621 1622 /* 1623 * the device list mutex makes sure that we don't change 1624 * the device list while someone else is writing out all 1625 * the device supers. Whoever is writing all supers, should 1626 * lock the device list mutex before getting the number of 1627 * devices in the super block (super_copy). Conversely, 1628 * whoever updates the number of devices in the super block 1629 * (super_copy) should hold the device list mutex. 1630 */ 1631 1632 cur_devices = device->fs_devices; 1633 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1634 list_del_rcu(&device->dev_list); 1635 1636 device->fs_devices->num_devices--; 1637 device->fs_devices->total_devices--; 1638 1639 if (device->missing) 1640 root->fs_info->fs_devices->missing_devices--; 1641 1642 next_device = list_entry(root->fs_info->fs_devices->devices.next, 1643 struct btrfs_device, dev_list); 1644 if (device->bdev == root->fs_info->sb->s_bdev) 1645 root->fs_info->sb->s_bdev = next_device->bdev; 1646 if (device->bdev == root->fs_info->fs_devices->latest_bdev) 1647 root->fs_info->fs_devices->latest_bdev = next_device->bdev; 1648 1649 if (device->bdev) 1650 device->fs_devices->open_devices--; 1651 1652 call_rcu(&device->rcu, free_device); 1653 1654 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1; 1655 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices); 1656 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1657 1658 if (cur_devices->open_devices == 0) { 1659 struct btrfs_fs_devices *fs_devices; 1660 fs_devices = root->fs_info->fs_devices; 1661 while (fs_devices) { 1662 if (fs_devices->seed == cur_devices) 1663 break; 1664 fs_devices = fs_devices->seed; 1665 } 1666 fs_devices->seed = cur_devices->seed; 1667 cur_devices->seed = NULL; 1668 lock_chunks(root); 1669 __btrfs_close_devices(cur_devices); 1670 unlock_chunks(root); 1671 free_fs_devices(cur_devices); 1672 } 1673 1674 root->fs_info->num_tolerated_disk_barrier_failures = 1675 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 1676 1677 /* 1678 * at this point, the device is zero sized. We want to 1679 * remove it from the devices list and zero out the old super 1680 */ 1681 if (clear_super && disk_super) { 1682 /* make sure this device isn't detected as part of 1683 * the FS anymore 1684 */ 1685 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 1686 set_buffer_dirty(bh); 1687 sync_dirty_buffer(bh); 1688 } 1689 1690 ret = 0; 1691 1692 /* Notify udev that device has changed */ 1693 if (bdev) 1694 btrfs_kobject_uevent(bdev, KOBJ_CHANGE); 1695 1696 error_brelse: 1697 brelse(bh); 1698 if (bdev) 1699 blkdev_put(bdev, FMODE_READ | FMODE_EXCL); 1700 out: 1701 mutex_unlock(&uuid_mutex); 1702 return ret; 1703 error_undo: 1704 if (device->writeable) { 1705 lock_chunks(root); 1706 list_add(&device->dev_alloc_list, 1707 &root->fs_info->fs_devices->alloc_list); 1708 unlock_chunks(root); 1709 root->fs_info->fs_devices->rw_devices++; 1710 } 1711 goto error_brelse; 1712 } 1713 1714 void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info, 1715 struct btrfs_device *srcdev) 1716 { 1717 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex)); 1718 list_del_rcu(&srcdev->dev_list); 1719 list_del_rcu(&srcdev->dev_alloc_list); 1720 fs_info->fs_devices->num_devices--; 1721 if (srcdev->missing) { 1722 fs_info->fs_devices->missing_devices--; 1723 fs_info->fs_devices->rw_devices++; 1724 } 1725 if (srcdev->can_discard) 1726 fs_info->fs_devices->num_can_discard--; 1727 if (srcdev->bdev) 1728 fs_info->fs_devices->open_devices--; 1729 1730 call_rcu(&srcdev->rcu, free_device); 1731 } 1732 1733 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 1734 struct btrfs_device *tgtdev) 1735 { 1736 struct btrfs_device *next_device; 1737 1738 WARN_ON(!tgtdev); 1739 mutex_lock(&fs_info->fs_devices->device_list_mutex); 1740 if (tgtdev->bdev) { 1741 btrfs_scratch_superblock(tgtdev); 1742 fs_info->fs_devices->open_devices--; 1743 } 1744 fs_info->fs_devices->num_devices--; 1745 if (tgtdev->can_discard) 1746 fs_info->fs_devices->num_can_discard++; 1747 1748 next_device = list_entry(fs_info->fs_devices->devices.next, 1749 struct btrfs_device, dev_list); 1750 if (tgtdev->bdev == fs_info->sb->s_bdev) 1751 fs_info->sb->s_bdev = next_device->bdev; 1752 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev) 1753 fs_info->fs_devices->latest_bdev = next_device->bdev; 1754 list_del_rcu(&tgtdev->dev_list); 1755 1756 call_rcu(&tgtdev->rcu, free_device); 1757 1758 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 1759 } 1760 1761 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path, 1762 struct btrfs_device **device) 1763 { 1764 int ret = 0; 1765 struct btrfs_super_block *disk_super; 1766 u64 devid; 1767 u8 *dev_uuid; 1768 struct block_device *bdev; 1769 struct buffer_head *bh; 1770 1771 *device = NULL; 1772 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ, 1773 root->fs_info->bdev_holder, 0, &bdev, &bh); 1774 if (ret) 1775 return ret; 1776 disk_super = (struct btrfs_super_block *)bh->b_data; 1777 devid = btrfs_stack_device_id(&disk_super->dev_item); 1778 dev_uuid = disk_super->dev_item.uuid; 1779 *device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1780 disk_super->fsid); 1781 brelse(bh); 1782 if (!*device) 1783 ret = -ENOENT; 1784 blkdev_put(bdev, FMODE_READ); 1785 return ret; 1786 } 1787 1788 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root, 1789 char *device_path, 1790 struct btrfs_device **device) 1791 { 1792 *device = NULL; 1793 if (strcmp(device_path, "missing") == 0) { 1794 struct list_head *devices; 1795 struct btrfs_device *tmp; 1796 1797 devices = &root->fs_info->fs_devices->devices; 1798 /* 1799 * It is safe to read the devices since the volume_mutex 1800 * is held by the caller. 1801 */ 1802 list_for_each_entry(tmp, devices, dev_list) { 1803 if (tmp->in_fs_metadata && !tmp->bdev) { 1804 *device = tmp; 1805 break; 1806 } 1807 } 1808 1809 if (!*device) { 1810 pr_err("btrfs: no missing device found\n"); 1811 return -ENOENT; 1812 } 1813 1814 return 0; 1815 } else { 1816 return btrfs_find_device_by_path(root, device_path, device); 1817 } 1818 } 1819 1820 /* 1821 * does all the dirty work required for changing file system's UUID. 1822 */ 1823 static int btrfs_prepare_sprout(struct btrfs_root *root) 1824 { 1825 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 1826 struct btrfs_fs_devices *old_devices; 1827 struct btrfs_fs_devices *seed_devices; 1828 struct btrfs_super_block *disk_super = root->fs_info->super_copy; 1829 struct btrfs_device *device; 1830 u64 super_flags; 1831 1832 BUG_ON(!mutex_is_locked(&uuid_mutex)); 1833 if (!fs_devices->seeding) 1834 return -EINVAL; 1835 1836 seed_devices = __alloc_fs_devices(); 1837 if (IS_ERR(seed_devices)) 1838 return PTR_ERR(seed_devices); 1839 1840 old_devices = clone_fs_devices(fs_devices); 1841 if (IS_ERR(old_devices)) { 1842 kfree(seed_devices); 1843 return PTR_ERR(old_devices); 1844 } 1845 1846 list_add(&old_devices->list, &fs_uuids); 1847 1848 memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); 1849 seed_devices->opened = 1; 1850 INIT_LIST_HEAD(&seed_devices->devices); 1851 INIT_LIST_HEAD(&seed_devices->alloc_list); 1852 mutex_init(&seed_devices->device_list_mutex); 1853 1854 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1855 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, 1856 synchronize_rcu); 1857 1858 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); 1859 list_for_each_entry(device, &seed_devices->devices, dev_list) { 1860 device->fs_devices = seed_devices; 1861 } 1862 1863 fs_devices->seeding = 0; 1864 fs_devices->num_devices = 0; 1865 fs_devices->open_devices = 0; 1866 fs_devices->total_devices = 0; 1867 fs_devices->seed = seed_devices; 1868 1869 generate_random_uuid(fs_devices->fsid); 1870 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1871 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1872 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1873 1874 super_flags = btrfs_super_flags(disk_super) & 1875 ~BTRFS_SUPER_FLAG_SEEDING; 1876 btrfs_set_super_flags(disk_super, super_flags); 1877 1878 return 0; 1879 } 1880 1881 /* 1882 * strore the expected generation for seed devices in device items. 1883 */ 1884 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans, 1885 struct btrfs_root *root) 1886 { 1887 struct btrfs_path *path; 1888 struct extent_buffer *leaf; 1889 struct btrfs_dev_item *dev_item; 1890 struct btrfs_device *device; 1891 struct btrfs_key key; 1892 u8 fs_uuid[BTRFS_UUID_SIZE]; 1893 u8 dev_uuid[BTRFS_UUID_SIZE]; 1894 u64 devid; 1895 int ret; 1896 1897 path = btrfs_alloc_path(); 1898 if (!path) 1899 return -ENOMEM; 1900 1901 root = root->fs_info->chunk_root; 1902 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1903 key.offset = 0; 1904 key.type = BTRFS_DEV_ITEM_KEY; 1905 1906 while (1) { 1907 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 1908 if (ret < 0) 1909 goto error; 1910 1911 leaf = path->nodes[0]; 1912 next_slot: 1913 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1914 ret = btrfs_next_leaf(root, path); 1915 if (ret > 0) 1916 break; 1917 if (ret < 0) 1918 goto error; 1919 leaf = path->nodes[0]; 1920 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1921 btrfs_release_path(path); 1922 continue; 1923 } 1924 1925 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1926 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || 1927 key.type != BTRFS_DEV_ITEM_KEY) 1928 break; 1929 1930 dev_item = btrfs_item_ptr(leaf, path->slots[0], 1931 struct btrfs_dev_item); 1932 devid = btrfs_device_id(leaf, dev_item); 1933 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item), 1934 BTRFS_UUID_SIZE); 1935 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item), 1936 BTRFS_UUID_SIZE); 1937 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1938 fs_uuid); 1939 BUG_ON(!device); /* Logic error */ 1940 1941 if (device->fs_devices->seeding) { 1942 btrfs_set_device_generation(leaf, dev_item, 1943 device->generation); 1944 btrfs_mark_buffer_dirty(leaf); 1945 } 1946 1947 path->slots[0]++; 1948 goto next_slot; 1949 } 1950 ret = 0; 1951 error: 1952 btrfs_free_path(path); 1953 return ret; 1954 } 1955 1956 int btrfs_init_new_device(struct btrfs_root *root, char *device_path) 1957 { 1958 struct request_queue *q; 1959 struct btrfs_trans_handle *trans; 1960 struct btrfs_device *device; 1961 struct block_device *bdev; 1962 struct list_head *devices; 1963 struct super_block *sb = root->fs_info->sb; 1964 struct rcu_string *name; 1965 u64 total_bytes; 1966 int seeding_dev = 0; 1967 int ret = 0; 1968 1969 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) 1970 return -EROFS; 1971 1972 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 1973 root->fs_info->bdev_holder); 1974 if (IS_ERR(bdev)) 1975 return PTR_ERR(bdev); 1976 1977 if (root->fs_info->fs_devices->seeding) { 1978 seeding_dev = 1; 1979 down_write(&sb->s_umount); 1980 mutex_lock(&uuid_mutex); 1981 } 1982 1983 filemap_write_and_wait(bdev->bd_inode->i_mapping); 1984 1985 devices = &root->fs_info->fs_devices->devices; 1986 1987 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1988 list_for_each_entry(device, devices, dev_list) { 1989 if (device->bdev == bdev) { 1990 ret = -EEXIST; 1991 mutex_unlock( 1992 &root->fs_info->fs_devices->device_list_mutex); 1993 goto error; 1994 } 1995 } 1996 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1997 1998 device = btrfs_alloc_device(root->fs_info, NULL, NULL); 1999 if (IS_ERR(device)) { 2000 /* we can safely leave the fs_devices entry around */ 2001 ret = PTR_ERR(device); 2002 goto error; 2003 } 2004 2005 name = rcu_string_strdup(device_path, GFP_NOFS); 2006 if (!name) { 2007 kfree(device); 2008 ret = -ENOMEM; 2009 goto error; 2010 } 2011 rcu_assign_pointer(device->name, name); 2012 2013 trans = btrfs_start_transaction(root, 0); 2014 if (IS_ERR(trans)) { 2015 rcu_string_free(device->name); 2016 kfree(device); 2017 ret = PTR_ERR(trans); 2018 goto error; 2019 } 2020 2021 lock_chunks(root); 2022 2023 q = bdev_get_queue(bdev); 2024 if (blk_queue_discard(q)) 2025 device->can_discard = 1; 2026 device->writeable = 1; 2027 device->generation = trans->transid; 2028 device->io_width = root->sectorsize; 2029 device->io_align = root->sectorsize; 2030 device->sector_size = root->sectorsize; 2031 device->total_bytes = i_size_read(bdev->bd_inode); 2032 device->disk_total_bytes = device->total_bytes; 2033 device->dev_root = root->fs_info->dev_root; 2034 device->bdev = bdev; 2035 device->in_fs_metadata = 1; 2036 device->is_tgtdev_for_dev_replace = 0; 2037 device->mode = FMODE_EXCL; 2038 set_blocksize(device->bdev, 4096); 2039 2040 if (seeding_dev) { 2041 sb->s_flags &= ~MS_RDONLY; 2042 ret = btrfs_prepare_sprout(root); 2043 BUG_ON(ret); /* -ENOMEM */ 2044 } 2045 2046 device->fs_devices = root->fs_info->fs_devices; 2047 2048 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2049 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices); 2050 list_add(&device->dev_alloc_list, 2051 &root->fs_info->fs_devices->alloc_list); 2052 root->fs_info->fs_devices->num_devices++; 2053 root->fs_info->fs_devices->open_devices++; 2054 root->fs_info->fs_devices->rw_devices++; 2055 root->fs_info->fs_devices->total_devices++; 2056 if (device->can_discard) 2057 root->fs_info->fs_devices->num_can_discard++; 2058 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes; 2059 2060 spin_lock(&root->fs_info->free_chunk_lock); 2061 root->fs_info->free_chunk_space += device->total_bytes; 2062 spin_unlock(&root->fs_info->free_chunk_lock); 2063 2064 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 2065 root->fs_info->fs_devices->rotating = 1; 2066 2067 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); 2068 btrfs_set_super_total_bytes(root->fs_info->super_copy, 2069 total_bytes + device->total_bytes); 2070 2071 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy); 2072 btrfs_set_super_num_devices(root->fs_info->super_copy, 2073 total_bytes + 1); 2074 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2075 2076 if (seeding_dev) { 2077 ret = init_first_rw_device(trans, root, device); 2078 if (ret) { 2079 btrfs_abort_transaction(trans, root, ret); 2080 goto error_trans; 2081 } 2082 ret = btrfs_finish_sprout(trans, root); 2083 if (ret) { 2084 btrfs_abort_transaction(trans, root, ret); 2085 goto error_trans; 2086 } 2087 } else { 2088 ret = btrfs_add_device(trans, root, device); 2089 if (ret) { 2090 btrfs_abort_transaction(trans, root, ret); 2091 goto error_trans; 2092 } 2093 } 2094 2095 /* 2096 * we've got more storage, clear any full flags on the space 2097 * infos 2098 */ 2099 btrfs_clear_space_info_full(root->fs_info); 2100 2101 unlock_chunks(root); 2102 root->fs_info->num_tolerated_disk_barrier_failures = 2103 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 2104 ret = btrfs_commit_transaction(trans, root); 2105 2106 if (seeding_dev) { 2107 mutex_unlock(&uuid_mutex); 2108 up_write(&sb->s_umount); 2109 2110 if (ret) /* transaction commit */ 2111 return ret; 2112 2113 ret = btrfs_relocate_sys_chunks(root); 2114 if (ret < 0) 2115 btrfs_error(root->fs_info, ret, 2116 "Failed to relocate sys chunks after " 2117 "device initialization. This can be fixed " 2118 "using the \"btrfs balance\" command."); 2119 trans = btrfs_attach_transaction(root); 2120 if (IS_ERR(trans)) { 2121 if (PTR_ERR(trans) == -ENOENT) 2122 return 0; 2123 return PTR_ERR(trans); 2124 } 2125 ret = btrfs_commit_transaction(trans, root); 2126 } 2127 2128 return ret; 2129 2130 error_trans: 2131 unlock_chunks(root); 2132 btrfs_end_transaction(trans, root); 2133 rcu_string_free(device->name); 2134 kfree(device); 2135 error: 2136 blkdev_put(bdev, FMODE_EXCL); 2137 if (seeding_dev) { 2138 mutex_unlock(&uuid_mutex); 2139 up_write(&sb->s_umount); 2140 } 2141 return ret; 2142 } 2143 2144 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path, 2145 struct btrfs_device **device_out) 2146 { 2147 struct request_queue *q; 2148 struct btrfs_device *device; 2149 struct block_device *bdev; 2150 struct btrfs_fs_info *fs_info = root->fs_info; 2151 struct list_head *devices; 2152 struct rcu_string *name; 2153 u64 devid = BTRFS_DEV_REPLACE_DEVID; 2154 int ret = 0; 2155 2156 *device_out = NULL; 2157 if (fs_info->fs_devices->seeding) 2158 return -EINVAL; 2159 2160 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 2161 fs_info->bdev_holder); 2162 if (IS_ERR(bdev)) 2163 return PTR_ERR(bdev); 2164 2165 filemap_write_and_wait(bdev->bd_inode->i_mapping); 2166 2167 devices = &fs_info->fs_devices->devices; 2168 list_for_each_entry(device, devices, dev_list) { 2169 if (device->bdev == bdev) { 2170 ret = -EEXIST; 2171 goto error; 2172 } 2173 } 2174 2175 device = btrfs_alloc_device(NULL, &devid, NULL); 2176 if (IS_ERR(device)) { 2177 ret = PTR_ERR(device); 2178 goto error; 2179 } 2180 2181 name = rcu_string_strdup(device_path, GFP_NOFS); 2182 if (!name) { 2183 kfree(device); 2184 ret = -ENOMEM; 2185 goto error; 2186 } 2187 rcu_assign_pointer(device->name, name); 2188 2189 q = bdev_get_queue(bdev); 2190 if (blk_queue_discard(q)) 2191 device->can_discard = 1; 2192 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2193 device->writeable = 1; 2194 device->generation = 0; 2195 device->io_width = root->sectorsize; 2196 device->io_align = root->sectorsize; 2197 device->sector_size = root->sectorsize; 2198 device->total_bytes = i_size_read(bdev->bd_inode); 2199 device->disk_total_bytes = device->total_bytes; 2200 device->dev_root = fs_info->dev_root; 2201 device->bdev = bdev; 2202 device->in_fs_metadata = 1; 2203 device->is_tgtdev_for_dev_replace = 1; 2204 device->mode = FMODE_EXCL; 2205 set_blocksize(device->bdev, 4096); 2206 device->fs_devices = fs_info->fs_devices; 2207 list_add(&device->dev_list, &fs_info->fs_devices->devices); 2208 fs_info->fs_devices->num_devices++; 2209 fs_info->fs_devices->open_devices++; 2210 if (device->can_discard) 2211 fs_info->fs_devices->num_can_discard++; 2212 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2213 2214 *device_out = device; 2215 return ret; 2216 2217 error: 2218 blkdev_put(bdev, FMODE_EXCL); 2219 return ret; 2220 } 2221 2222 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, 2223 struct btrfs_device *tgtdev) 2224 { 2225 WARN_ON(fs_info->fs_devices->rw_devices == 0); 2226 tgtdev->io_width = fs_info->dev_root->sectorsize; 2227 tgtdev->io_align = fs_info->dev_root->sectorsize; 2228 tgtdev->sector_size = fs_info->dev_root->sectorsize; 2229 tgtdev->dev_root = fs_info->dev_root; 2230 tgtdev->in_fs_metadata = 1; 2231 } 2232 2233 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, 2234 struct btrfs_device *device) 2235 { 2236 int ret; 2237 struct btrfs_path *path; 2238 struct btrfs_root *root; 2239 struct btrfs_dev_item *dev_item; 2240 struct extent_buffer *leaf; 2241 struct btrfs_key key; 2242 2243 root = device->dev_root->fs_info->chunk_root; 2244 2245 path = btrfs_alloc_path(); 2246 if (!path) 2247 return -ENOMEM; 2248 2249 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 2250 key.type = BTRFS_DEV_ITEM_KEY; 2251 key.offset = device->devid; 2252 2253 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2254 if (ret < 0) 2255 goto out; 2256 2257 if (ret > 0) { 2258 ret = -ENOENT; 2259 goto out; 2260 } 2261 2262 leaf = path->nodes[0]; 2263 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 2264 2265 btrfs_set_device_id(leaf, dev_item, device->devid); 2266 btrfs_set_device_type(leaf, dev_item, device->type); 2267 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 2268 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 2269 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 2270 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes); 2271 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 2272 btrfs_mark_buffer_dirty(leaf); 2273 2274 out: 2275 btrfs_free_path(path); 2276 return ret; 2277 } 2278 2279 static int __btrfs_grow_device(struct btrfs_trans_handle *trans, 2280 struct btrfs_device *device, u64 new_size) 2281 { 2282 struct btrfs_super_block *super_copy = 2283 device->dev_root->fs_info->super_copy; 2284 u64 old_total = btrfs_super_total_bytes(super_copy); 2285 u64 diff = new_size - device->total_bytes; 2286 2287 if (!device->writeable) 2288 return -EACCES; 2289 if (new_size <= device->total_bytes || 2290 device->is_tgtdev_for_dev_replace) 2291 return -EINVAL; 2292 2293 btrfs_set_super_total_bytes(super_copy, old_total + diff); 2294 device->fs_devices->total_rw_bytes += diff; 2295 2296 device->total_bytes = new_size; 2297 device->disk_total_bytes = new_size; 2298 btrfs_clear_space_info_full(device->dev_root->fs_info); 2299 2300 return btrfs_update_device(trans, device); 2301 } 2302 2303 int btrfs_grow_device(struct btrfs_trans_handle *trans, 2304 struct btrfs_device *device, u64 new_size) 2305 { 2306 int ret; 2307 lock_chunks(device->dev_root); 2308 ret = __btrfs_grow_device(trans, device, new_size); 2309 unlock_chunks(device->dev_root); 2310 return ret; 2311 } 2312 2313 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, 2314 struct btrfs_root *root, 2315 u64 chunk_tree, u64 chunk_objectid, 2316 u64 chunk_offset) 2317 { 2318 int ret; 2319 struct btrfs_path *path; 2320 struct btrfs_key key; 2321 2322 root = root->fs_info->chunk_root; 2323 path = btrfs_alloc_path(); 2324 if (!path) 2325 return -ENOMEM; 2326 2327 key.objectid = chunk_objectid; 2328 key.offset = chunk_offset; 2329 key.type = BTRFS_CHUNK_ITEM_KEY; 2330 2331 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2332 if (ret < 0) 2333 goto out; 2334 else if (ret > 0) { /* Logic error or corruption */ 2335 btrfs_error(root->fs_info, -ENOENT, 2336 "Failed lookup while freeing chunk."); 2337 ret = -ENOENT; 2338 goto out; 2339 } 2340 2341 ret = btrfs_del_item(trans, root, path); 2342 if (ret < 0) 2343 btrfs_error(root->fs_info, ret, 2344 "Failed to delete chunk item."); 2345 out: 2346 btrfs_free_path(path); 2347 return ret; 2348 } 2349 2350 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 2351 chunk_offset) 2352 { 2353 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 2354 struct btrfs_disk_key *disk_key; 2355 struct btrfs_chunk *chunk; 2356 u8 *ptr; 2357 int ret = 0; 2358 u32 num_stripes; 2359 u32 array_size; 2360 u32 len = 0; 2361 u32 cur; 2362 struct btrfs_key key; 2363 2364 array_size = btrfs_super_sys_array_size(super_copy); 2365 2366 ptr = super_copy->sys_chunk_array; 2367 cur = 0; 2368 2369 while (cur < array_size) { 2370 disk_key = (struct btrfs_disk_key *)ptr; 2371 btrfs_disk_key_to_cpu(&key, disk_key); 2372 2373 len = sizeof(*disk_key); 2374 2375 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 2376 chunk = (struct btrfs_chunk *)(ptr + len); 2377 num_stripes = btrfs_stack_chunk_num_stripes(chunk); 2378 len += btrfs_chunk_item_size(num_stripes); 2379 } else { 2380 ret = -EIO; 2381 break; 2382 } 2383 if (key.objectid == chunk_objectid && 2384 key.offset == chunk_offset) { 2385 memmove(ptr, ptr + len, array_size - (cur + len)); 2386 array_size -= len; 2387 btrfs_set_super_sys_array_size(super_copy, array_size); 2388 } else { 2389 ptr += len; 2390 cur += len; 2391 } 2392 } 2393 return ret; 2394 } 2395 2396 static int btrfs_relocate_chunk(struct btrfs_root *root, 2397 u64 chunk_tree, u64 chunk_objectid, 2398 u64 chunk_offset) 2399 { 2400 struct extent_map_tree *em_tree; 2401 struct btrfs_root *extent_root; 2402 struct btrfs_trans_handle *trans; 2403 struct extent_map *em; 2404 struct map_lookup *map; 2405 int ret; 2406 int i; 2407 2408 root = root->fs_info->chunk_root; 2409 extent_root = root->fs_info->extent_root; 2410 em_tree = &root->fs_info->mapping_tree.map_tree; 2411 2412 ret = btrfs_can_relocate(extent_root, chunk_offset); 2413 if (ret) 2414 return -ENOSPC; 2415 2416 /* step one, relocate all the extents inside this chunk */ 2417 ret = btrfs_relocate_block_group(extent_root, chunk_offset); 2418 if (ret) 2419 return ret; 2420 2421 trans = btrfs_start_transaction(root, 0); 2422 if (IS_ERR(trans)) { 2423 ret = PTR_ERR(trans); 2424 btrfs_std_error(root->fs_info, ret); 2425 return ret; 2426 } 2427 2428 lock_chunks(root); 2429 2430 /* 2431 * step two, delete the device extents and the 2432 * chunk tree entries 2433 */ 2434 read_lock(&em_tree->lock); 2435 em = lookup_extent_mapping(em_tree, chunk_offset, 1); 2436 read_unlock(&em_tree->lock); 2437 2438 BUG_ON(!em || em->start > chunk_offset || 2439 em->start + em->len < chunk_offset); 2440 map = (struct map_lookup *)em->bdev; 2441 2442 for (i = 0; i < map->num_stripes; i++) { 2443 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, 2444 map->stripes[i].physical); 2445 BUG_ON(ret); 2446 2447 if (map->stripes[i].dev) { 2448 ret = btrfs_update_device(trans, map->stripes[i].dev); 2449 BUG_ON(ret); 2450 } 2451 } 2452 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, 2453 chunk_offset); 2454 2455 BUG_ON(ret); 2456 2457 trace_btrfs_chunk_free(root, map, chunk_offset, em->len); 2458 2459 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 2460 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); 2461 BUG_ON(ret); 2462 } 2463 2464 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset); 2465 BUG_ON(ret); 2466 2467 write_lock(&em_tree->lock); 2468 remove_extent_mapping(em_tree, em); 2469 write_unlock(&em_tree->lock); 2470 2471 kfree(map); 2472 em->bdev = NULL; 2473 2474 /* once for the tree */ 2475 free_extent_map(em); 2476 /* once for us */ 2477 free_extent_map(em); 2478 2479 unlock_chunks(root); 2480 btrfs_end_transaction(trans, root); 2481 return 0; 2482 } 2483 2484 static int btrfs_relocate_sys_chunks(struct btrfs_root *root) 2485 { 2486 struct btrfs_root *chunk_root = root->fs_info->chunk_root; 2487 struct btrfs_path *path; 2488 struct extent_buffer *leaf; 2489 struct btrfs_chunk *chunk; 2490 struct btrfs_key key; 2491 struct btrfs_key found_key; 2492 u64 chunk_tree = chunk_root->root_key.objectid; 2493 u64 chunk_type; 2494 bool retried = false; 2495 int failed = 0; 2496 int ret; 2497 2498 path = btrfs_alloc_path(); 2499 if (!path) 2500 return -ENOMEM; 2501 2502 again: 2503 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2504 key.offset = (u64)-1; 2505 key.type = BTRFS_CHUNK_ITEM_KEY; 2506 2507 while (1) { 2508 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2509 if (ret < 0) 2510 goto error; 2511 BUG_ON(ret == 0); /* Corruption */ 2512 2513 ret = btrfs_previous_item(chunk_root, path, key.objectid, 2514 key.type); 2515 if (ret < 0) 2516 goto error; 2517 if (ret > 0) 2518 break; 2519 2520 leaf = path->nodes[0]; 2521 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2522 2523 chunk = btrfs_item_ptr(leaf, path->slots[0], 2524 struct btrfs_chunk); 2525 chunk_type = btrfs_chunk_type(leaf, chunk); 2526 btrfs_release_path(path); 2527 2528 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { 2529 ret = btrfs_relocate_chunk(chunk_root, chunk_tree, 2530 found_key.objectid, 2531 found_key.offset); 2532 if (ret == -ENOSPC) 2533 failed++; 2534 else if (ret) 2535 BUG(); 2536 } 2537 2538 if (found_key.offset == 0) 2539 break; 2540 key.offset = found_key.offset - 1; 2541 } 2542 ret = 0; 2543 if (failed && !retried) { 2544 failed = 0; 2545 retried = true; 2546 goto again; 2547 } else if (failed && retried) { 2548 WARN_ON(1); 2549 ret = -ENOSPC; 2550 } 2551 error: 2552 btrfs_free_path(path); 2553 return ret; 2554 } 2555 2556 static int insert_balance_item(struct btrfs_root *root, 2557 struct btrfs_balance_control *bctl) 2558 { 2559 struct btrfs_trans_handle *trans; 2560 struct btrfs_balance_item *item; 2561 struct btrfs_disk_balance_args disk_bargs; 2562 struct btrfs_path *path; 2563 struct extent_buffer *leaf; 2564 struct btrfs_key key; 2565 int ret, err; 2566 2567 path = btrfs_alloc_path(); 2568 if (!path) 2569 return -ENOMEM; 2570 2571 trans = btrfs_start_transaction(root, 0); 2572 if (IS_ERR(trans)) { 2573 btrfs_free_path(path); 2574 return PTR_ERR(trans); 2575 } 2576 2577 key.objectid = BTRFS_BALANCE_OBJECTID; 2578 key.type = BTRFS_BALANCE_ITEM_KEY; 2579 key.offset = 0; 2580 2581 ret = btrfs_insert_empty_item(trans, root, path, &key, 2582 sizeof(*item)); 2583 if (ret) 2584 goto out; 2585 2586 leaf = path->nodes[0]; 2587 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 2588 2589 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); 2590 2591 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); 2592 btrfs_set_balance_data(leaf, item, &disk_bargs); 2593 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); 2594 btrfs_set_balance_meta(leaf, item, &disk_bargs); 2595 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); 2596 btrfs_set_balance_sys(leaf, item, &disk_bargs); 2597 2598 btrfs_set_balance_flags(leaf, item, bctl->flags); 2599 2600 btrfs_mark_buffer_dirty(leaf); 2601 out: 2602 btrfs_free_path(path); 2603 err = btrfs_commit_transaction(trans, root); 2604 if (err && !ret) 2605 ret = err; 2606 return ret; 2607 } 2608 2609 static int del_balance_item(struct btrfs_root *root) 2610 { 2611 struct btrfs_trans_handle *trans; 2612 struct btrfs_path *path; 2613 struct btrfs_key key; 2614 int ret, err; 2615 2616 path = btrfs_alloc_path(); 2617 if (!path) 2618 return -ENOMEM; 2619 2620 trans = btrfs_start_transaction(root, 0); 2621 if (IS_ERR(trans)) { 2622 btrfs_free_path(path); 2623 return PTR_ERR(trans); 2624 } 2625 2626 key.objectid = BTRFS_BALANCE_OBJECTID; 2627 key.type = BTRFS_BALANCE_ITEM_KEY; 2628 key.offset = 0; 2629 2630 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2631 if (ret < 0) 2632 goto out; 2633 if (ret > 0) { 2634 ret = -ENOENT; 2635 goto out; 2636 } 2637 2638 ret = btrfs_del_item(trans, root, path); 2639 out: 2640 btrfs_free_path(path); 2641 err = btrfs_commit_transaction(trans, root); 2642 if (err && !ret) 2643 ret = err; 2644 return ret; 2645 } 2646 2647 /* 2648 * This is a heuristic used to reduce the number of chunks balanced on 2649 * resume after balance was interrupted. 2650 */ 2651 static void update_balance_args(struct btrfs_balance_control *bctl) 2652 { 2653 /* 2654 * Turn on soft mode for chunk types that were being converted. 2655 */ 2656 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) 2657 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; 2658 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) 2659 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; 2660 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) 2661 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; 2662 2663 /* 2664 * Turn on usage filter if is not already used. The idea is 2665 * that chunks that we have already balanced should be 2666 * reasonably full. Don't do it for chunks that are being 2667 * converted - that will keep us from relocating unconverted 2668 * (albeit full) chunks. 2669 */ 2670 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && 2671 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2672 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; 2673 bctl->data.usage = 90; 2674 } 2675 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && 2676 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2677 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; 2678 bctl->sys.usage = 90; 2679 } 2680 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && 2681 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2682 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; 2683 bctl->meta.usage = 90; 2684 } 2685 } 2686 2687 /* 2688 * Should be called with both balance and volume mutexes held to 2689 * serialize other volume operations (add_dev/rm_dev/resize) with 2690 * restriper. Same goes for unset_balance_control. 2691 */ 2692 static void set_balance_control(struct btrfs_balance_control *bctl) 2693 { 2694 struct btrfs_fs_info *fs_info = bctl->fs_info; 2695 2696 BUG_ON(fs_info->balance_ctl); 2697 2698 spin_lock(&fs_info->balance_lock); 2699 fs_info->balance_ctl = bctl; 2700 spin_unlock(&fs_info->balance_lock); 2701 } 2702 2703 static void unset_balance_control(struct btrfs_fs_info *fs_info) 2704 { 2705 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2706 2707 BUG_ON(!fs_info->balance_ctl); 2708 2709 spin_lock(&fs_info->balance_lock); 2710 fs_info->balance_ctl = NULL; 2711 spin_unlock(&fs_info->balance_lock); 2712 2713 kfree(bctl); 2714 } 2715 2716 /* 2717 * Balance filters. Return 1 if chunk should be filtered out 2718 * (should not be balanced). 2719 */ 2720 static int chunk_profiles_filter(u64 chunk_type, 2721 struct btrfs_balance_args *bargs) 2722 { 2723 chunk_type = chunk_to_extended(chunk_type) & 2724 BTRFS_EXTENDED_PROFILE_MASK; 2725 2726 if (bargs->profiles & chunk_type) 2727 return 0; 2728 2729 return 1; 2730 } 2731 2732 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, 2733 struct btrfs_balance_args *bargs) 2734 { 2735 struct btrfs_block_group_cache *cache; 2736 u64 chunk_used, user_thresh; 2737 int ret = 1; 2738 2739 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 2740 chunk_used = btrfs_block_group_used(&cache->item); 2741 2742 if (bargs->usage == 0) 2743 user_thresh = 1; 2744 else if (bargs->usage > 100) 2745 user_thresh = cache->key.offset; 2746 else 2747 user_thresh = div_factor_fine(cache->key.offset, 2748 bargs->usage); 2749 2750 if (chunk_used < user_thresh) 2751 ret = 0; 2752 2753 btrfs_put_block_group(cache); 2754 return ret; 2755 } 2756 2757 static int chunk_devid_filter(struct extent_buffer *leaf, 2758 struct btrfs_chunk *chunk, 2759 struct btrfs_balance_args *bargs) 2760 { 2761 struct btrfs_stripe *stripe; 2762 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2763 int i; 2764 2765 for (i = 0; i < num_stripes; i++) { 2766 stripe = btrfs_stripe_nr(chunk, i); 2767 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) 2768 return 0; 2769 } 2770 2771 return 1; 2772 } 2773 2774 /* [pstart, pend) */ 2775 static int chunk_drange_filter(struct extent_buffer *leaf, 2776 struct btrfs_chunk *chunk, 2777 u64 chunk_offset, 2778 struct btrfs_balance_args *bargs) 2779 { 2780 struct btrfs_stripe *stripe; 2781 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2782 u64 stripe_offset; 2783 u64 stripe_length; 2784 int factor; 2785 int i; 2786 2787 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) 2788 return 0; 2789 2790 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP | 2791 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) { 2792 factor = num_stripes / 2; 2793 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) { 2794 factor = num_stripes - 1; 2795 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) { 2796 factor = num_stripes - 2; 2797 } else { 2798 factor = num_stripes; 2799 } 2800 2801 for (i = 0; i < num_stripes; i++) { 2802 stripe = btrfs_stripe_nr(chunk, i); 2803 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) 2804 continue; 2805 2806 stripe_offset = btrfs_stripe_offset(leaf, stripe); 2807 stripe_length = btrfs_chunk_length(leaf, chunk); 2808 do_div(stripe_length, factor); 2809 2810 if (stripe_offset < bargs->pend && 2811 stripe_offset + stripe_length > bargs->pstart) 2812 return 0; 2813 } 2814 2815 return 1; 2816 } 2817 2818 /* [vstart, vend) */ 2819 static int chunk_vrange_filter(struct extent_buffer *leaf, 2820 struct btrfs_chunk *chunk, 2821 u64 chunk_offset, 2822 struct btrfs_balance_args *bargs) 2823 { 2824 if (chunk_offset < bargs->vend && 2825 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) 2826 /* at least part of the chunk is inside this vrange */ 2827 return 0; 2828 2829 return 1; 2830 } 2831 2832 static int chunk_soft_convert_filter(u64 chunk_type, 2833 struct btrfs_balance_args *bargs) 2834 { 2835 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) 2836 return 0; 2837 2838 chunk_type = chunk_to_extended(chunk_type) & 2839 BTRFS_EXTENDED_PROFILE_MASK; 2840 2841 if (bargs->target == chunk_type) 2842 return 1; 2843 2844 return 0; 2845 } 2846 2847 static int should_balance_chunk(struct btrfs_root *root, 2848 struct extent_buffer *leaf, 2849 struct btrfs_chunk *chunk, u64 chunk_offset) 2850 { 2851 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl; 2852 struct btrfs_balance_args *bargs = NULL; 2853 u64 chunk_type = btrfs_chunk_type(leaf, chunk); 2854 2855 /* type filter */ 2856 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & 2857 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { 2858 return 0; 2859 } 2860 2861 if (chunk_type & BTRFS_BLOCK_GROUP_DATA) 2862 bargs = &bctl->data; 2863 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) 2864 bargs = &bctl->sys; 2865 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) 2866 bargs = &bctl->meta; 2867 2868 /* profiles filter */ 2869 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && 2870 chunk_profiles_filter(chunk_type, bargs)) { 2871 return 0; 2872 } 2873 2874 /* usage filter */ 2875 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && 2876 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) { 2877 return 0; 2878 } 2879 2880 /* devid filter */ 2881 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && 2882 chunk_devid_filter(leaf, chunk, bargs)) { 2883 return 0; 2884 } 2885 2886 /* drange filter, makes sense only with devid filter */ 2887 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && 2888 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) { 2889 return 0; 2890 } 2891 2892 /* vrange filter */ 2893 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && 2894 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { 2895 return 0; 2896 } 2897 2898 /* soft profile changing mode */ 2899 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && 2900 chunk_soft_convert_filter(chunk_type, bargs)) { 2901 return 0; 2902 } 2903 2904 return 1; 2905 } 2906 2907 static int __btrfs_balance(struct btrfs_fs_info *fs_info) 2908 { 2909 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2910 struct btrfs_root *chunk_root = fs_info->chunk_root; 2911 struct btrfs_root *dev_root = fs_info->dev_root; 2912 struct list_head *devices; 2913 struct btrfs_device *device; 2914 u64 old_size; 2915 u64 size_to_free; 2916 struct btrfs_chunk *chunk; 2917 struct btrfs_path *path; 2918 struct btrfs_key key; 2919 struct btrfs_key found_key; 2920 struct btrfs_trans_handle *trans; 2921 struct extent_buffer *leaf; 2922 int slot; 2923 int ret; 2924 int enospc_errors = 0; 2925 bool counting = true; 2926 2927 /* step one make some room on all the devices */ 2928 devices = &fs_info->fs_devices->devices; 2929 list_for_each_entry(device, devices, dev_list) { 2930 old_size = device->total_bytes; 2931 size_to_free = div_factor(old_size, 1); 2932 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024); 2933 if (!device->writeable || 2934 device->total_bytes - device->bytes_used > size_to_free || 2935 device->is_tgtdev_for_dev_replace) 2936 continue; 2937 2938 ret = btrfs_shrink_device(device, old_size - size_to_free); 2939 if (ret == -ENOSPC) 2940 break; 2941 BUG_ON(ret); 2942 2943 trans = btrfs_start_transaction(dev_root, 0); 2944 BUG_ON(IS_ERR(trans)); 2945 2946 ret = btrfs_grow_device(trans, device, old_size); 2947 BUG_ON(ret); 2948 2949 btrfs_end_transaction(trans, dev_root); 2950 } 2951 2952 /* step two, relocate all the chunks */ 2953 path = btrfs_alloc_path(); 2954 if (!path) { 2955 ret = -ENOMEM; 2956 goto error; 2957 } 2958 2959 /* zero out stat counters */ 2960 spin_lock(&fs_info->balance_lock); 2961 memset(&bctl->stat, 0, sizeof(bctl->stat)); 2962 spin_unlock(&fs_info->balance_lock); 2963 again: 2964 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2965 key.offset = (u64)-1; 2966 key.type = BTRFS_CHUNK_ITEM_KEY; 2967 2968 while (1) { 2969 if ((!counting && atomic_read(&fs_info->balance_pause_req)) || 2970 atomic_read(&fs_info->balance_cancel_req)) { 2971 ret = -ECANCELED; 2972 goto error; 2973 } 2974 2975 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2976 if (ret < 0) 2977 goto error; 2978 2979 /* 2980 * this shouldn't happen, it means the last relocate 2981 * failed 2982 */ 2983 if (ret == 0) 2984 BUG(); /* FIXME break ? */ 2985 2986 ret = btrfs_previous_item(chunk_root, path, 0, 2987 BTRFS_CHUNK_ITEM_KEY); 2988 if (ret) { 2989 ret = 0; 2990 break; 2991 } 2992 2993 leaf = path->nodes[0]; 2994 slot = path->slots[0]; 2995 btrfs_item_key_to_cpu(leaf, &found_key, slot); 2996 2997 if (found_key.objectid != key.objectid) 2998 break; 2999 3000 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 3001 3002 if (!counting) { 3003 spin_lock(&fs_info->balance_lock); 3004 bctl->stat.considered++; 3005 spin_unlock(&fs_info->balance_lock); 3006 } 3007 3008 ret = should_balance_chunk(chunk_root, leaf, chunk, 3009 found_key.offset); 3010 btrfs_release_path(path); 3011 if (!ret) 3012 goto loop; 3013 3014 if (counting) { 3015 spin_lock(&fs_info->balance_lock); 3016 bctl->stat.expected++; 3017 spin_unlock(&fs_info->balance_lock); 3018 goto loop; 3019 } 3020 3021 ret = btrfs_relocate_chunk(chunk_root, 3022 chunk_root->root_key.objectid, 3023 found_key.objectid, 3024 found_key.offset); 3025 if (ret && ret != -ENOSPC) 3026 goto error; 3027 if (ret == -ENOSPC) { 3028 enospc_errors++; 3029 } else { 3030 spin_lock(&fs_info->balance_lock); 3031 bctl->stat.completed++; 3032 spin_unlock(&fs_info->balance_lock); 3033 } 3034 loop: 3035 if (found_key.offset == 0) 3036 break; 3037 key.offset = found_key.offset - 1; 3038 } 3039 3040 if (counting) { 3041 btrfs_release_path(path); 3042 counting = false; 3043 goto again; 3044 } 3045 error: 3046 btrfs_free_path(path); 3047 if (enospc_errors) { 3048 printk(KERN_INFO "btrfs: %d enospc errors during balance\n", 3049 enospc_errors); 3050 if (!ret) 3051 ret = -ENOSPC; 3052 } 3053 3054 return ret; 3055 } 3056 3057 /** 3058 * alloc_profile_is_valid - see if a given profile is valid and reduced 3059 * @flags: profile to validate 3060 * @extended: if true @flags is treated as an extended profile 3061 */ 3062 static int alloc_profile_is_valid(u64 flags, int extended) 3063 { 3064 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK : 3065 BTRFS_BLOCK_GROUP_PROFILE_MASK); 3066 3067 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK; 3068 3069 /* 1) check that all other bits are zeroed */ 3070 if (flags & ~mask) 3071 return 0; 3072 3073 /* 2) see if profile is reduced */ 3074 if (flags == 0) 3075 return !extended; /* "0" is valid for usual profiles */ 3076 3077 /* true if exactly one bit set */ 3078 return (flags & (flags - 1)) == 0; 3079 } 3080 3081 static inline int balance_need_close(struct btrfs_fs_info *fs_info) 3082 { 3083 /* cancel requested || normal exit path */ 3084 return atomic_read(&fs_info->balance_cancel_req) || 3085 (atomic_read(&fs_info->balance_pause_req) == 0 && 3086 atomic_read(&fs_info->balance_cancel_req) == 0); 3087 } 3088 3089 static void __cancel_balance(struct btrfs_fs_info *fs_info) 3090 { 3091 int ret; 3092 3093 unset_balance_control(fs_info); 3094 ret = del_balance_item(fs_info->tree_root); 3095 if (ret) 3096 btrfs_std_error(fs_info, ret); 3097 3098 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3099 } 3100 3101 /* 3102 * Should be called with both balance and volume mutexes held 3103 */ 3104 int btrfs_balance(struct btrfs_balance_control *bctl, 3105 struct btrfs_ioctl_balance_args *bargs) 3106 { 3107 struct btrfs_fs_info *fs_info = bctl->fs_info; 3108 u64 allowed; 3109 int mixed = 0; 3110 int ret; 3111 u64 num_devices; 3112 unsigned seq; 3113 3114 if (btrfs_fs_closing(fs_info) || 3115 atomic_read(&fs_info->balance_pause_req) || 3116 atomic_read(&fs_info->balance_cancel_req)) { 3117 ret = -EINVAL; 3118 goto out; 3119 } 3120 3121 allowed = btrfs_super_incompat_flags(fs_info->super_copy); 3122 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) 3123 mixed = 1; 3124 3125 /* 3126 * In case of mixed groups both data and meta should be picked, 3127 * and identical options should be given for both of them. 3128 */ 3129 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA; 3130 if (mixed && (bctl->flags & allowed)) { 3131 if (!(bctl->flags & BTRFS_BALANCE_DATA) || 3132 !(bctl->flags & BTRFS_BALANCE_METADATA) || 3133 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { 3134 printk(KERN_ERR "btrfs: with mixed groups data and " 3135 "metadata balance options must be the same\n"); 3136 ret = -EINVAL; 3137 goto out; 3138 } 3139 } 3140 3141 num_devices = fs_info->fs_devices->num_devices; 3142 btrfs_dev_replace_lock(&fs_info->dev_replace); 3143 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { 3144 BUG_ON(num_devices < 1); 3145 num_devices--; 3146 } 3147 btrfs_dev_replace_unlock(&fs_info->dev_replace); 3148 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; 3149 if (num_devices == 1) 3150 allowed |= BTRFS_BLOCK_GROUP_DUP; 3151 else if (num_devices > 1) 3152 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1); 3153 if (num_devices > 2) 3154 allowed |= BTRFS_BLOCK_GROUP_RAID5; 3155 if (num_devices > 3) 3156 allowed |= (BTRFS_BLOCK_GROUP_RAID10 | 3157 BTRFS_BLOCK_GROUP_RAID6); 3158 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3159 (!alloc_profile_is_valid(bctl->data.target, 1) || 3160 (bctl->data.target & ~allowed))) { 3161 printk(KERN_ERR "btrfs: unable to start balance with target " 3162 "data profile %llu\n", 3163 bctl->data.target); 3164 ret = -EINVAL; 3165 goto out; 3166 } 3167 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3168 (!alloc_profile_is_valid(bctl->meta.target, 1) || 3169 (bctl->meta.target & ~allowed))) { 3170 printk(KERN_ERR "btrfs: unable to start balance with target " 3171 "metadata profile %llu\n", 3172 bctl->meta.target); 3173 ret = -EINVAL; 3174 goto out; 3175 } 3176 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3177 (!alloc_profile_is_valid(bctl->sys.target, 1) || 3178 (bctl->sys.target & ~allowed))) { 3179 printk(KERN_ERR "btrfs: unable to start balance with target " 3180 "system profile %llu\n", 3181 bctl->sys.target); 3182 ret = -EINVAL; 3183 goto out; 3184 } 3185 3186 /* allow dup'ed data chunks only in mixed mode */ 3187 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3188 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) { 3189 printk(KERN_ERR "btrfs: dup for data is not allowed\n"); 3190 ret = -EINVAL; 3191 goto out; 3192 } 3193 3194 /* allow to reduce meta or sys integrity only if force set */ 3195 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | 3196 BTRFS_BLOCK_GROUP_RAID10 | 3197 BTRFS_BLOCK_GROUP_RAID5 | 3198 BTRFS_BLOCK_GROUP_RAID6; 3199 do { 3200 seq = read_seqbegin(&fs_info->profiles_lock); 3201 3202 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3203 (fs_info->avail_system_alloc_bits & allowed) && 3204 !(bctl->sys.target & allowed)) || 3205 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3206 (fs_info->avail_metadata_alloc_bits & allowed) && 3207 !(bctl->meta.target & allowed))) { 3208 if (bctl->flags & BTRFS_BALANCE_FORCE) { 3209 printk(KERN_INFO "btrfs: force reducing metadata " 3210 "integrity\n"); 3211 } else { 3212 printk(KERN_ERR "btrfs: balance will reduce metadata " 3213 "integrity, use force if you want this\n"); 3214 ret = -EINVAL; 3215 goto out; 3216 } 3217 } 3218 } while (read_seqretry(&fs_info->profiles_lock, seq)); 3219 3220 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3221 int num_tolerated_disk_barrier_failures; 3222 u64 target = bctl->sys.target; 3223 3224 num_tolerated_disk_barrier_failures = 3225 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3226 if (num_tolerated_disk_barrier_failures > 0 && 3227 (target & 3228 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 | 3229 BTRFS_AVAIL_ALLOC_BIT_SINGLE))) 3230 num_tolerated_disk_barrier_failures = 0; 3231 else if (num_tolerated_disk_barrier_failures > 1 && 3232 (target & 3233 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10))) 3234 num_tolerated_disk_barrier_failures = 1; 3235 3236 fs_info->num_tolerated_disk_barrier_failures = 3237 num_tolerated_disk_barrier_failures; 3238 } 3239 3240 ret = insert_balance_item(fs_info->tree_root, bctl); 3241 if (ret && ret != -EEXIST) 3242 goto out; 3243 3244 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { 3245 BUG_ON(ret == -EEXIST); 3246 set_balance_control(bctl); 3247 } else { 3248 BUG_ON(ret != -EEXIST); 3249 spin_lock(&fs_info->balance_lock); 3250 update_balance_args(bctl); 3251 spin_unlock(&fs_info->balance_lock); 3252 } 3253 3254 atomic_inc(&fs_info->balance_running); 3255 mutex_unlock(&fs_info->balance_mutex); 3256 3257 ret = __btrfs_balance(fs_info); 3258 3259 mutex_lock(&fs_info->balance_mutex); 3260 atomic_dec(&fs_info->balance_running); 3261 3262 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3263 fs_info->num_tolerated_disk_barrier_failures = 3264 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3265 } 3266 3267 if (bargs) { 3268 memset(bargs, 0, sizeof(*bargs)); 3269 update_ioctl_balance_args(fs_info, 0, bargs); 3270 } 3271 3272 if ((ret && ret != -ECANCELED && ret != -ENOSPC) || 3273 balance_need_close(fs_info)) { 3274 __cancel_balance(fs_info); 3275 } 3276 3277 wake_up(&fs_info->balance_wait_q); 3278 3279 return ret; 3280 out: 3281 if (bctl->flags & BTRFS_BALANCE_RESUME) 3282 __cancel_balance(fs_info); 3283 else { 3284 kfree(bctl); 3285 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3286 } 3287 return ret; 3288 } 3289 3290 static int balance_kthread(void *data) 3291 { 3292 struct btrfs_fs_info *fs_info = data; 3293 int ret = 0; 3294 3295 mutex_lock(&fs_info->volume_mutex); 3296 mutex_lock(&fs_info->balance_mutex); 3297 3298 if (fs_info->balance_ctl) { 3299 printk(KERN_INFO "btrfs: continuing balance\n"); 3300 ret = btrfs_balance(fs_info->balance_ctl, NULL); 3301 } 3302 3303 mutex_unlock(&fs_info->balance_mutex); 3304 mutex_unlock(&fs_info->volume_mutex); 3305 3306 return ret; 3307 } 3308 3309 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info) 3310 { 3311 struct task_struct *tsk; 3312 3313 spin_lock(&fs_info->balance_lock); 3314 if (!fs_info->balance_ctl) { 3315 spin_unlock(&fs_info->balance_lock); 3316 return 0; 3317 } 3318 spin_unlock(&fs_info->balance_lock); 3319 3320 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) { 3321 printk(KERN_INFO "btrfs: force skipping balance\n"); 3322 return 0; 3323 } 3324 3325 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance"); 3326 return PTR_ERR_OR_ZERO(tsk); 3327 } 3328 3329 int btrfs_recover_balance(struct btrfs_fs_info *fs_info) 3330 { 3331 struct btrfs_balance_control *bctl; 3332 struct btrfs_balance_item *item; 3333 struct btrfs_disk_balance_args disk_bargs; 3334 struct btrfs_path *path; 3335 struct extent_buffer *leaf; 3336 struct btrfs_key key; 3337 int ret; 3338 3339 path = btrfs_alloc_path(); 3340 if (!path) 3341 return -ENOMEM; 3342 3343 key.objectid = BTRFS_BALANCE_OBJECTID; 3344 key.type = BTRFS_BALANCE_ITEM_KEY; 3345 key.offset = 0; 3346 3347 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 3348 if (ret < 0) 3349 goto out; 3350 if (ret > 0) { /* ret = -ENOENT; */ 3351 ret = 0; 3352 goto out; 3353 } 3354 3355 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3356 if (!bctl) { 3357 ret = -ENOMEM; 3358 goto out; 3359 } 3360 3361 leaf = path->nodes[0]; 3362 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 3363 3364 bctl->fs_info = fs_info; 3365 bctl->flags = btrfs_balance_flags(leaf, item); 3366 bctl->flags |= BTRFS_BALANCE_RESUME; 3367 3368 btrfs_balance_data(leaf, item, &disk_bargs); 3369 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); 3370 btrfs_balance_meta(leaf, item, &disk_bargs); 3371 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); 3372 btrfs_balance_sys(leaf, item, &disk_bargs); 3373 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); 3374 3375 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)); 3376 3377 mutex_lock(&fs_info->volume_mutex); 3378 mutex_lock(&fs_info->balance_mutex); 3379 3380 set_balance_control(bctl); 3381 3382 mutex_unlock(&fs_info->balance_mutex); 3383 mutex_unlock(&fs_info->volume_mutex); 3384 out: 3385 btrfs_free_path(path); 3386 return ret; 3387 } 3388 3389 int btrfs_pause_balance(struct btrfs_fs_info *fs_info) 3390 { 3391 int ret = 0; 3392 3393 mutex_lock(&fs_info->balance_mutex); 3394 if (!fs_info->balance_ctl) { 3395 mutex_unlock(&fs_info->balance_mutex); 3396 return -ENOTCONN; 3397 } 3398 3399 if (atomic_read(&fs_info->balance_running)) { 3400 atomic_inc(&fs_info->balance_pause_req); 3401 mutex_unlock(&fs_info->balance_mutex); 3402 3403 wait_event(fs_info->balance_wait_q, 3404 atomic_read(&fs_info->balance_running) == 0); 3405 3406 mutex_lock(&fs_info->balance_mutex); 3407 /* we are good with balance_ctl ripped off from under us */ 3408 BUG_ON(atomic_read(&fs_info->balance_running)); 3409 atomic_dec(&fs_info->balance_pause_req); 3410 } else { 3411 ret = -ENOTCONN; 3412 } 3413 3414 mutex_unlock(&fs_info->balance_mutex); 3415 return ret; 3416 } 3417 3418 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) 3419 { 3420 mutex_lock(&fs_info->balance_mutex); 3421 if (!fs_info->balance_ctl) { 3422 mutex_unlock(&fs_info->balance_mutex); 3423 return -ENOTCONN; 3424 } 3425 3426 atomic_inc(&fs_info->balance_cancel_req); 3427 /* 3428 * if we are running just wait and return, balance item is 3429 * deleted in btrfs_balance in this case 3430 */ 3431 if (atomic_read(&fs_info->balance_running)) { 3432 mutex_unlock(&fs_info->balance_mutex); 3433 wait_event(fs_info->balance_wait_q, 3434 atomic_read(&fs_info->balance_running) == 0); 3435 mutex_lock(&fs_info->balance_mutex); 3436 } else { 3437 /* __cancel_balance needs volume_mutex */ 3438 mutex_unlock(&fs_info->balance_mutex); 3439 mutex_lock(&fs_info->volume_mutex); 3440 mutex_lock(&fs_info->balance_mutex); 3441 3442 if (fs_info->balance_ctl) 3443 __cancel_balance(fs_info); 3444 3445 mutex_unlock(&fs_info->volume_mutex); 3446 } 3447 3448 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running)); 3449 atomic_dec(&fs_info->balance_cancel_req); 3450 mutex_unlock(&fs_info->balance_mutex); 3451 return 0; 3452 } 3453 3454 static int btrfs_uuid_scan_kthread(void *data) 3455 { 3456 struct btrfs_fs_info *fs_info = data; 3457 struct btrfs_root *root = fs_info->tree_root; 3458 struct btrfs_key key; 3459 struct btrfs_key max_key; 3460 struct btrfs_path *path = NULL; 3461 int ret = 0; 3462 struct extent_buffer *eb; 3463 int slot; 3464 struct btrfs_root_item root_item; 3465 u32 item_size; 3466 struct btrfs_trans_handle *trans = NULL; 3467 3468 path = btrfs_alloc_path(); 3469 if (!path) { 3470 ret = -ENOMEM; 3471 goto out; 3472 } 3473 3474 key.objectid = 0; 3475 key.type = BTRFS_ROOT_ITEM_KEY; 3476 key.offset = 0; 3477 3478 max_key.objectid = (u64)-1; 3479 max_key.type = BTRFS_ROOT_ITEM_KEY; 3480 max_key.offset = (u64)-1; 3481 3482 path->keep_locks = 1; 3483 3484 while (1) { 3485 ret = btrfs_search_forward(root, &key, &max_key, path, 0); 3486 if (ret) { 3487 if (ret > 0) 3488 ret = 0; 3489 break; 3490 } 3491 3492 if (key.type != BTRFS_ROOT_ITEM_KEY || 3493 (key.objectid < BTRFS_FIRST_FREE_OBJECTID && 3494 key.objectid != BTRFS_FS_TREE_OBJECTID) || 3495 key.objectid > BTRFS_LAST_FREE_OBJECTID) 3496 goto skip; 3497 3498 eb = path->nodes[0]; 3499 slot = path->slots[0]; 3500 item_size = btrfs_item_size_nr(eb, slot); 3501 if (item_size < sizeof(root_item)) 3502 goto skip; 3503 3504 read_extent_buffer(eb, &root_item, 3505 btrfs_item_ptr_offset(eb, slot), 3506 (int)sizeof(root_item)); 3507 if (btrfs_root_refs(&root_item) == 0) 3508 goto skip; 3509 3510 if (!btrfs_is_empty_uuid(root_item.uuid) || 3511 !btrfs_is_empty_uuid(root_item.received_uuid)) { 3512 if (trans) 3513 goto update_tree; 3514 3515 btrfs_release_path(path); 3516 /* 3517 * 1 - subvol uuid item 3518 * 1 - received_subvol uuid item 3519 */ 3520 trans = btrfs_start_transaction(fs_info->uuid_root, 2); 3521 if (IS_ERR(trans)) { 3522 ret = PTR_ERR(trans); 3523 break; 3524 } 3525 continue; 3526 } else { 3527 goto skip; 3528 } 3529 update_tree: 3530 if (!btrfs_is_empty_uuid(root_item.uuid)) { 3531 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root, 3532 root_item.uuid, 3533 BTRFS_UUID_KEY_SUBVOL, 3534 key.objectid); 3535 if (ret < 0) { 3536 pr_warn("btrfs: uuid_tree_add failed %d\n", 3537 ret); 3538 break; 3539 } 3540 } 3541 3542 if (!btrfs_is_empty_uuid(root_item.received_uuid)) { 3543 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root, 3544 root_item.received_uuid, 3545 BTRFS_UUID_KEY_RECEIVED_SUBVOL, 3546 key.objectid); 3547 if (ret < 0) { 3548 pr_warn("btrfs: uuid_tree_add failed %d\n", 3549 ret); 3550 break; 3551 } 3552 } 3553 3554 skip: 3555 if (trans) { 3556 ret = btrfs_end_transaction(trans, fs_info->uuid_root); 3557 trans = NULL; 3558 if (ret) 3559 break; 3560 } 3561 3562 btrfs_release_path(path); 3563 if (key.offset < (u64)-1) { 3564 key.offset++; 3565 } else if (key.type < BTRFS_ROOT_ITEM_KEY) { 3566 key.offset = 0; 3567 key.type = BTRFS_ROOT_ITEM_KEY; 3568 } else if (key.objectid < (u64)-1) { 3569 key.offset = 0; 3570 key.type = BTRFS_ROOT_ITEM_KEY; 3571 key.objectid++; 3572 } else { 3573 break; 3574 } 3575 cond_resched(); 3576 } 3577 3578 out: 3579 btrfs_free_path(path); 3580 if (trans && !IS_ERR(trans)) 3581 btrfs_end_transaction(trans, fs_info->uuid_root); 3582 if (ret) 3583 pr_warn("btrfs: btrfs_uuid_scan_kthread failed %d\n", ret); 3584 else 3585 fs_info->update_uuid_tree_gen = 1; 3586 up(&fs_info->uuid_tree_rescan_sem); 3587 return 0; 3588 } 3589 3590 /* 3591 * Callback for btrfs_uuid_tree_iterate(). 3592 * returns: 3593 * 0 check succeeded, the entry is not outdated. 3594 * < 0 if an error occured. 3595 * > 0 if the check failed, which means the caller shall remove the entry. 3596 */ 3597 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info, 3598 u8 *uuid, u8 type, u64 subid) 3599 { 3600 struct btrfs_key key; 3601 int ret = 0; 3602 struct btrfs_root *subvol_root; 3603 3604 if (type != BTRFS_UUID_KEY_SUBVOL && 3605 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL) 3606 goto out; 3607 3608 key.objectid = subid; 3609 key.type = BTRFS_ROOT_ITEM_KEY; 3610 key.offset = (u64)-1; 3611 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key); 3612 if (IS_ERR(subvol_root)) { 3613 ret = PTR_ERR(subvol_root); 3614 if (ret == -ENOENT) 3615 ret = 1; 3616 goto out; 3617 } 3618 3619 switch (type) { 3620 case BTRFS_UUID_KEY_SUBVOL: 3621 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE)) 3622 ret = 1; 3623 break; 3624 case BTRFS_UUID_KEY_RECEIVED_SUBVOL: 3625 if (memcmp(uuid, subvol_root->root_item.received_uuid, 3626 BTRFS_UUID_SIZE)) 3627 ret = 1; 3628 break; 3629 } 3630 3631 out: 3632 return ret; 3633 } 3634 3635 static int btrfs_uuid_rescan_kthread(void *data) 3636 { 3637 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data; 3638 int ret; 3639 3640 /* 3641 * 1st step is to iterate through the existing UUID tree and 3642 * to delete all entries that contain outdated data. 3643 * 2nd step is to add all missing entries to the UUID tree. 3644 */ 3645 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry); 3646 if (ret < 0) { 3647 pr_warn("btrfs: iterating uuid_tree failed %d\n", ret); 3648 up(&fs_info->uuid_tree_rescan_sem); 3649 return ret; 3650 } 3651 return btrfs_uuid_scan_kthread(data); 3652 } 3653 3654 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info) 3655 { 3656 struct btrfs_trans_handle *trans; 3657 struct btrfs_root *tree_root = fs_info->tree_root; 3658 struct btrfs_root *uuid_root; 3659 struct task_struct *task; 3660 int ret; 3661 3662 /* 3663 * 1 - root node 3664 * 1 - root item 3665 */ 3666 trans = btrfs_start_transaction(tree_root, 2); 3667 if (IS_ERR(trans)) 3668 return PTR_ERR(trans); 3669 3670 uuid_root = btrfs_create_tree(trans, fs_info, 3671 BTRFS_UUID_TREE_OBJECTID); 3672 if (IS_ERR(uuid_root)) { 3673 btrfs_abort_transaction(trans, tree_root, 3674 PTR_ERR(uuid_root)); 3675 return PTR_ERR(uuid_root); 3676 } 3677 3678 fs_info->uuid_root = uuid_root; 3679 3680 ret = btrfs_commit_transaction(trans, tree_root); 3681 if (ret) 3682 return ret; 3683 3684 down(&fs_info->uuid_tree_rescan_sem); 3685 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid"); 3686 if (IS_ERR(task)) { 3687 /* fs_info->update_uuid_tree_gen remains 0 in all error case */ 3688 pr_warn("btrfs: failed to start uuid_scan task\n"); 3689 up(&fs_info->uuid_tree_rescan_sem); 3690 return PTR_ERR(task); 3691 } 3692 3693 return 0; 3694 } 3695 3696 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info) 3697 { 3698 struct task_struct *task; 3699 3700 down(&fs_info->uuid_tree_rescan_sem); 3701 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid"); 3702 if (IS_ERR(task)) { 3703 /* fs_info->update_uuid_tree_gen remains 0 in all error case */ 3704 pr_warn("btrfs: failed to start uuid_rescan task\n"); 3705 up(&fs_info->uuid_tree_rescan_sem); 3706 return PTR_ERR(task); 3707 } 3708 3709 return 0; 3710 } 3711 3712 /* 3713 * shrinking a device means finding all of the device extents past 3714 * the new size, and then following the back refs to the chunks. 3715 * The chunk relocation code actually frees the device extent 3716 */ 3717 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 3718 { 3719 struct btrfs_trans_handle *trans; 3720 struct btrfs_root *root = device->dev_root; 3721 struct btrfs_dev_extent *dev_extent = NULL; 3722 struct btrfs_path *path; 3723 u64 length; 3724 u64 chunk_tree; 3725 u64 chunk_objectid; 3726 u64 chunk_offset; 3727 int ret; 3728 int slot; 3729 int failed = 0; 3730 bool retried = false; 3731 struct extent_buffer *l; 3732 struct btrfs_key key; 3733 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3734 u64 old_total = btrfs_super_total_bytes(super_copy); 3735 u64 old_size = device->total_bytes; 3736 u64 diff = device->total_bytes - new_size; 3737 3738 if (device->is_tgtdev_for_dev_replace) 3739 return -EINVAL; 3740 3741 path = btrfs_alloc_path(); 3742 if (!path) 3743 return -ENOMEM; 3744 3745 path->reada = 2; 3746 3747 lock_chunks(root); 3748 3749 device->total_bytes = new_size; 3750 if (device->writeable) { 3751 device->fs_devices->total_rw_bytes -= diff; 3752 spin_lock(&root->fs_info->free_chunk_lock); 3753 root->fs_info->free_chunk_space -= diff; 3754 spin_unlock(&root->fs_info->free_chunk_lock); 3755 } 3756 unlock_chunks(root); 3757 3758 again: 3759 key.objectid = device->devid; 3760 key.offset = (u64)-1; 3761 key.type = BTRFS_DEV_EXTENT_KEY; 3762 3763 do { 3764 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3765 if (ret < 0) 3766 goto done; 3767 3768 ret = btrfs_previous_item(root, path, 0, key.type); 3769 if (ret < 0) 3770 goto done; 3771 if (ret) { 3772 ret = 0; 3773 btrfs_release_path(path); 3774 break; 3775 } 3776 3777 l = path->nodes[0]; 3778 slot = path->slots[0]; 3779 btrfs_item_key_to_cpu(l, &key, path->slots[0]); 3780 3781 if (key.objectid != device->devid) { 3782 btrfs_release_path(path); 3783 break; 3784 } 3785 3786 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 3787 length = btrfs_dev_extent_length(l, dev_extent); 3788 3789 if (key.offset + length <= new_size) { 3790 btrfs_release_path(path); 3791 break; 3792 } 3793 3794 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); 3795 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); 3796 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); 3797 btrfs_release_path(path); 3798 3799 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, 3800 chunk_offset); 3801 if (ret && ret != -ENOSPC) 3802 goto done; 3803 if (ret == -ENOSPC) 3804 failed++; 3805 } while (key.offset-- > 0); 3806 3807 if (failed && !retried) { 3808 failed = 0; 3809 retried = true; 3810 goto again; 3811 } else if (failed && retried) { 3812 ret = -ENOSPC; 3813 lock_chunks(root); 3814 3815 device->total_bytes = old_size; 3816 if (device->writeable) 3817 device->fs_devices->total_rw_bytes += diff; 3818 spin_lock(&root->fs_info->free_chunk_lock); 3819 root->fs_info->free_chunk_space += diff; 3820 spin_unlock(&root->fs_info->free_chunk_lock); 3821 unlock_chunks(root); 3822 goto done; 3823 } 3824 3825 /* Shrinking succeeded, else we would be at "done". */ 3826 trans = btrfs_start_transaction(root, 0); 3827 if (IS_ERR(trans)) { 3828 ret = PTR_ERR(trans); 3829 goto done; 3830 } 3831 3832 lock_chunks(root); 3833 3834 device->disk_total_bytes = new_size; 3835 /* Now btrfs_update_device() will change the on-disk size. */ 3836 ret = btrfs_update_device(trans, device); 3837 if (ret) { 3838 unlock_chunks(root); 3839 btrfs_end_transaction(trans, root); 3840 goto done; 3841 } 3842 WARN_ON(diff > old_total); 3843 btrfs_set_super_total_bytes(super_copy, old_total - diff); 3844 unlock_chunks(root); 3845 btrfs_end_transaction(trans, root); 3846 done: 3847 btrfs_free_path(path); 3848 return ret; 3849 } 3850 3851 static int btrfs_add_system_chunk(struct btrfs_root *root, 3852 struct btrfs_key *key, 3853 struct btrfs_chunk *chunk, int item_size) 3854 { 3855 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3856 struct btrfs_disk_key disk_key; 3857 u32 array_size; 3858 u8 *ptr; 3859 3860 array_size = btrfs_super_sys_array_size(super_copy); 3861 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) 3862 return -EFBIG; 3863 3864 ptr = super_copy->sys_chunk_array + array_size; 3865 btrfs_cpu_key_to_disk(&disk_key, key); 3866 memcpy(ptr, &disk_key, sizeof(disk_key)); 3867 ptr += sizeof(disk_key); 3868 memcpy(ptr, chunk, item_size); 3869 item_size += sizeof(disk_key); 3870 btrfs_set_super_sys_array_size(super_copy, array_size + item_size); 3871 return 0; 3872 } 3873 3874 /* 3875 * sort the devices in descending order by max_avail, total_avail 3876 */ 3877 static int btrfs_cmp_device_info(const void *a, const void *b) 3878 { 3879 const struct btrfs_device_info *di_a = a; 3880 const struct btrfs_device_info *di_b = b; 3881 3882 if (di_a->max_avail > di_b->max_avail) 3883 return -1; 3884 if (di_a->max_avail < di_b->max_avail) 3885 return 1; 3886 if (di_a->total_avail > di_b->total_avail) 3887 return -1; 3888 if (di_a->total_avail < di_b->total_avail) 3889 return 1; 3890 return 0; 3891 } 3892 3893 static struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { 3894 [BTRFS_RAID_RAID10] = { 3895 .sub_stripes = 2, 3896 .dev_stripes = 1, 3897 .devs_max = 0, /* 0 == as many as possible */ 3898 .devs_min = 4, 3899 .devs_increment = 2, 3900 .ncopies = 2, 3901 }, 3902 [BTRFS_RAID_RAID1] = { 3903 .sub_stripes = 1, 3904 .dev_stripes = 1, 3905 .devs_max = 2, 3906 .devs_min = 2, 3907 .devs_increment = 2, 3908 .ncopies = 2, 3909 }, 3910 [BTRFS_RAID_DUP] = { 3911 .sub_stripes = 1, 3912 .dev_stripes = 2, 3913 .devs_max = 1, 3914 .devs_min = 1, 3915 .devs_increment = 1, 3916 .ncopies = 2, 3917 }, 3918 [BTRFS_RAID_RAID0] = { 3919 .sub_stripes = 1, 3920 .dev_stripes = 1, 3921 .devs_max = 0, 3922 .devs_min = 2, 3923 .devs_increment = 1, 3924 .ncopies = 1, 3925 }, 3926 [BTRFS_RAID_SINGLE] = { 3927 .sub_stripes = 1, 3928 .dev_stripes = 1, 3929 .devs_max = 1, 3930 .devs_min = 1, 3931 .devs_increment = 1, 3932 .ncopies = 1, 3933 }, 3934 [BTRFS_RAID_RAID5] = { 3935 .sub_stripes = 1, 3936 .dev_stripes = 1, 3937 .devs_max = 0, 3938 .devs_min = 2, 3939 .devs_increment = 1, 3940 .ncopies = 2, 3941 }, 3942 [BTRFS_RAID_RAID6] = { 3943 .sub_stripes = 1, 3944 .dev_stripes = 1, 3945 .devs_max = 0, 3946 .devs_min = 3, 3947 .devs_increment = 1, 3948 .ncopies = 3, 3949 }, 3950 }; 3951 3952 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target) 3953 { 3954 /* TODO allow them to set a preferred stripe size */ 3955 return 64 * 1024; 3956 } 3957 3958 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type) 3959 { 3960 if (!(type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))) 3961 return; 3962 3963 btrfs_set_fs_incompat(info, RAID56); 3964 } 3965 3966 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 3967 struct btrfs_root *extent_root, u64 start, 3968 u64 type) 3969 { 3970 struct btrfs_fs_info *info = extent_root->fs_info; 3971 struct btrfs_fs_devices *fs_devices = info->fs_devices; 3972 struct list_head *cur; 3973 struct map_lookup *map = NULL; 3974 struct extent_map_tree *em_tree; 3975 struct extent_map *em; 3976 struct btrfs_device_info *devices_info = NULL; 3977 u64 total_avail; 3978 int num_stripes; /* total number of stripes to allocate */ 3979 int data_stripes; /* number of stripes that count for 3980 block group size */ 3981 int sub_stripes; /* sub_stripes info for map */ 3982 int dev_stripes; /* stripes per dev */ 3983 int devs_max; /* max devs to use */ 3984 int devs_min; /* min devs needed */ 3985 int devs_increment; /* ndevs has to be a multiple of this */ 3986 int ncopies; /* how many copies to data has */ 3987 int ret; 3988 u64 max_stripe_size; 3989 u64 max_chunk_size; 3990 u64 stripe_size; 3991 u64 num_bytes; 3992 u64 raid_stripe_len = BTRFS_STRIPE_LEN; 3993 int ndevs; 3994 int i; 3995 int j; 3996 int index; 3997 3998 BUG_ON(!alloc_profile_is_valid(type, 0)); 3999 4000 if (list_empty(&fs_devices->alloc_list)) 4001 return -ENOSPC; 4002 4003 index = __get_raid_index(type); 4004 4005 sub_stripes = btrfs_raid_array[index].sub_stripes; 4006 dev_stripes = btrfs_raid_array[index].dev_stripes; 4007 devs_max = btrfs_raid_array[index].devs_max; 4008 devs_min = btrfs_raid_array[index].devs_min; 4009 devs_increment = btrfs_raid_array[index].devs_increment; 4010 ncopies = btrfs_raid_array[index].ncopies; 4011 4012 if (type & BTRFS_BLOCK_GROUP_DATA) { 4013 max_stripe_size = 1024 * 1024 * 1024; 4014 max_chunk_size = 10 * max_stripe_size; 4015 } else if (type & BTRFS_BLOCK_GROUP_METADATA) { 4016 /* for larger filesystems, use larger metadata chunks */ 4017 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024) 4018 max_stripe_size = 1024 * 1024 * 1024; 4019 else 4020 max_stripe_size = 256 * 1024 * 1024; 4021 max_chunk_size = max_stripe_size; 4022 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { 4023 max_stripe_size = 32 * 1024 * 1024; 4024 max_chunk_size = 2 * max_stripe_size; 4025 } else { 4026 printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n", 4027 type); 4028 BUG_ON(1); 4029 } 4030 4031 /* we don't want a chunk larger than 10% of writeable space */ 4032 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1), 4033 max_chunk_size); 4034 4035 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices, 4036 GFP_NOFS); 4037 if (!devices_info) 4038 return -ENOMEM; 4039 4040 cur = fs_devices->alloc_list.next; 4041 4042 /* 4043 * in the first pass through the devices list, we gather information 4044 * about the available holes on each device. 4045 */ 4046 ndevs = 0; 4047 while (cur != &fs_devices->alloc_list) { 4048 struct btrfs_device *device; 4049 u64 max_avail; 4050 u64 dev_offset; 4051 4052 device = list_entry(cur, struct btrfs_device, dev_alloc_list); 4053 4054 cur = cur->next; 4055 4056 if (!device->writeable) { 4057 WARN(1, KERN_ERR 4058 "btrfs: read-only device in alloc_list\n"); 4059 continue; 4060 } 4061 4062 if (!device->in_fs_metadata || 4063 device->is_tgtdev_for_dev_replace) 4064 continue; 4065 4066 if (device->total_bytes > device->bytes_used) 4067 total_avail = device->total_bytes - device->bytes_used; 4068 else 4069 total_avail = 0; 4070 4071 /* If there is no space on this device, skip it. */ 4072 if (total_avail == 0) 4073 continue; 4074 4075 ret = find_free_dev_extent(trans, device, 4076 max_stripe_size * dev_stripes, 4077 &dev_offset, &max_avail); 4078 if (ret && ret != -ENOSPC) 4079 goto error; 4080 4081 if (ret == 0) 4082 max_avail = max_stripe_size * dev_stripes; 4083 4084 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes) 4085 continue; 4086 4087 if (ndevs == fs_devices->rw_devices) { 4088 WARN(1, "%s: found more than %llu devices\n", 4089 __func__, fs_devices->rw_devices); 4090 break; 4091 } 4092 devices_info[ndevs].dev_offset = dev_offset; 4093 devices_info[ndevs].max_avail = max_avail; 4094 devices_info[ndevs].total_avail = total_avail; 4095 devices_info[ndevs].dev = device; 4096 ++ndevs; 4097 } 4098 4099 /* 4100 * now sort the devices by hole size / available space 4101 */ 4102 sort(devices_info, ndevs, sizeof(struct btrfs_device_info), 4103 btrfs_cmp_device_info, NULL); 4104 4105 /* round down to number of usable stripes */ 4106 ndevs -= ndevs % devs_increment; 4107 4108 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) { 4109 ret = -ENOSPC; 4110 goto error; 4111 } 4112 4113 if (devs_max && ndevs > devs_max) 4114 ndevs = devs_max; 4115 /* 4116 * the primary goal is to maximize the number of stripes, so use as many 4117 * devices as possible, even if the stripes are not maximum sized. 4118 */ 4119 stripe_size = devices_info[ndevs-1].max_avail; 4120 num_stripes = ndevs * dev_stripes; 4121 4122 /* 4123 * this will have to be fixed for RAID1 and RAID10 over 4124 * more drives 4125 */ 4126 data_stripes = num_stripes / ncopies; 4127 4128 if (type & BTRFS_BLOCK_GROUP_RAID5) { 4129 raid_stripe_len = find_raid56_stripe_len(ndevs - 1, 4130 btrfs_super_stripesize(info->super_copy)); 4131 data_stripes = num_stripes - 1; 4132 } 4133 if (type & BTRFS_BLOCK_GROUP_RAID6) { 4134 raid_stripe_len = find_raid56_stripe_len(ndevs - 2, 4135 btrfs_super_stripesize(info->super_copy)); 4136 data_stripes = num_stripes - 2; 4137 } 4138 4139 /* 4140 * Use the number of data stripes to figure out how big this chunk 4141 * is really going to be in terms of logical address space, 4142 * and compare that answer with the max chunk size 4143 */ 4144 if (stripe_size * data_stripes > max_chunk_size) { 4145 u64 mask = (1ULL << 24) - 1; 4146 stripe_size = max_chunk_size; 4147 do_div(stripe_size, data_stripes); 4148 4149 /* bump the answer up to a 16MB boundary */ 4150 stripe_size = (stripe_size + mask) & ~mask; 4151 4152 /* but don't go higher than the limits we found 4153 * while searching for free extents 4154 */ 4155 if (stripe_size > devices_info[ndevs-1].max_avail) 4156 stripe_size = devices_info[ndevs-1].max_avail; 4157 } 4158 4159 do_div(stripe_size, dev_stripes); 4160 4161 /* align to BTRFS_STRIPE_LEN */ 4162 do_div(stripe_size, raid_stripe_len); 4163 stripe_size *= raid_stripe_len; 4164 4165 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 4166 if (!map) { 4167 ret = -ENOMEM; 4168 goto error; 4169 } 4170 map->num_stripes = num_stripes; 4171 4172 for (i = 0; i < ndevs; ++i) { 4173 for (j = 0; j < dev_stripes; ++j) { 4174 int s = i * dev_stripes + j; 4175 map->stripes[s].dev = devices_info[i].dev; 4176 map->stripes[s].physical = devices_info[i].dev_offset + 4177 j * stripe_size; 4178 } 4179 } 4180 map->sector_size = extent_root->sectorsize; 4181 map->stripe_len = raid_stripe_len; 4182 map->io_align = raid_stripe_len; 4183 map->io_width = raid_stripe_len; 4184 map->type = type; 4185 map->sub_stripes = sub_stripes; 4186 4187 num_bytes = stripe_size * data_stripes; 4188 4189 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes); 4190 4191 em = alloc_extent_map(); 4192 if (!em) { 4193 ret = -ENOMEM; 4194 goto error; 4195 } 4196 em->bdev = (struct block_device *)map; 4197 em->start = start; 4198 em->len = num_bytes; 4199 em->block_start = 0; 4200 em->block_len = em->len; 4201 em->orig_block_len = stripe_size; 4202 4203 em_tree = &extent_root->fs_info->mapping_tree.map_tree; 4204 write_lock(&em_tree->lock); 4205 ret = add_extent_mapping(em_tree, em, 0); 4206 if (!ret) { 4207 list_add_tail(&em->list, &trans->transaction->pending_chunks); 4208 atomic_inc(&em->refs); 4209 } 4210 write_unlock(&em_tree->lock); 4211 if (ret) { 4212 free_extent_map(em); 4213 goto error; 4214 } 4215 4216 ret = btrfs_make_block_group(trans, extent_root, 0, type, 4217 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 4218 start, num_bytes); 4219 if (ret) 4220 goto error_del_extent; 4221 4222 free_extent_map(em); 4223 check_raid56_incompat_flag(extent_root->fs_info, type); 4224 4225 kfree(devices_info); 4226 return 0; 4227 4228 error_del_extent: 4229 write_lock(&em_tree->lock); 4230 remove_extent_mapping(em_tree, em); 4231 write_unlock(&em_tree->lock); 4232 4233 /* One for our allocation */ 4234 free_extent_map(em); 4235 /* One for the tree reference */ 4236 free_extent_map(em); 4237 error: 4238 kfree(map); 4239 kfree(devices_info); 4240 return ret; 4241 } 4242 4243 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans, 4244 struct btrfs_root *extent_root, 4245 u64 chunk_offset, u64 chunk_size) 4246 { 4247 struct btrfs_key key; 4248 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 4249 struct btrfs_device *device; 4250 struct btrfs_chunk *chunk; 4251 struct btrfs_stripe *stripe; 4252 struct extent_map_tree *em_tree; 4253 struct extent_map *em; 4254 struct map_lookup *map; 4255 size_t item_size; 4256 u64 dev_offset; 4257 u64 stripe_size; 4258 int i = 0; 4259 int ret; 4260 4261 em_tree = &extent_root->fs_info->mapping_tree.map_tree; 4262 read_lock(&em_tree->lock); 4263 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size); 4264 read_unlock(&em_tree->lock); 4265 4266 if (!em) { 4267 btrfs_crit(extent_root->fs_info, "unable to find logical " 4268 "%Lu len %Lu", chunk_offset, chunk_size); 4269 return -EINVAL; 4270 } 4271 4272 if (em->start != chunk_offset || em->len != chunk_size) { 4273 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted" 4274 " %Lu-%Lu, found %Lu-%Lu\n", chunk_offset, 4275 chunk_size, em->start, em->len); 4276 free_extent_map(em); 4277 return -EINVAL; 4278 } 4279 4280 map = (struct map_lookup *)em->bdev; 4281 item_size = btrfs_chunk_item_size(map->num_stripes); 4282 stripe_size = em->orig_block_len; 4283 4284 chunk = kzalloc(item_size, GFP_NOFS); 4285 if (!chunk) { 4286 ret = -ENOMEM; 4287 goto out; 4288 } 4289 4290 for (i = 0; i < map->num_stripes; i++) { 4291 device = map->stripes[i].dev; 4292 dev_offset = map->stripes[i].physical; 4293 4294 device->bytes_used += stripe_size; 4295 ret = btrfs_update_device(trans, device); 4296 if (ret) 4297 goto out; 4298 ret = btrfs_alloc_dev_extent(trans, device, 4299 chunk_root->root_key.objectid, 4300 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 4301 chunk_offset, dev_offset, 4302 stripe_size); 4303 if (ret) 4304 goto out; 4305 } 4306 4307 spin_lock(&extent_root->fs_info->free_chunk_lock); 4308 extent_root->fs_info->free_chunk_space -= (stripe_size * 4309 map->num_stripes); 4310 spin_unlock(&extent_root->fs_info->free_chunk_lock); 4311 4312 stripe = &chunk->stripe; 4313 for (i = 0; i < map->num_stripes; i++) { 4314 device = map->stripes[i].dev; 4315 dev_offset = map->stripes[i].physical; 4316 4317 btrfs_set_stack_stripe_devid(stripe, device->devid); 4318 btrfs_set_stack_stripe_offset(stripe, dev_offset); 4319 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); 4320 stripe++; 4321 } 4322 4323 btrfs_set_stack_chunk_length(chunk, chunk_size); 4324 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); 4325 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); 4326 btrfs_set_stack_chunk_type(chunk, map->type); 4327 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); 4328 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); 4329 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); 4330 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); 4331 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); 4332 4333 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 4334 key.type = BTRFS_CHUNK_ITEM_KEY; 4335 key.offset = chunk_offset; 4336 4337 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); 4338 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 4339 /* 4340 * TODO: Cleanup of inserted chunk root in case of 4341 * failure. 4342 */ 4343 ret = btrfs_add_system_chunk(chunk_root, &key, chunk, 4344 item_size); 4345 } 4346 4347 out: 4348 kfree(chunk); 4349 free_extent_map(em); 4350 return ret; 4351 } 4352 4353 /* 4354 * Chunk allocation falls into two parts. The first part does works 4355 * that make the new allocated chunk useable, but not do any operation 4356 * that modifies the chunk tree. The second part does the works that 4357 * require modifying the chunk tree. This division is important for the 4358 * bootstrap process of adding storage to a seed btrfs. 4359 */ 4360 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 4361 struct btrfs_root *extent_root, u64 type) 4362 { 4363 u64 chunk_offset; 4364 4365 chunk_offset = find_next_chunk(extent_root->fs_info); 4366 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type); 4367 } 4368 4369 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans, 4370 struct btrfs_root *root, 4371 struct btrfs_device *device) 4372 { 4373 u64 chunk_offset; 4374 u64 sys_chunk_offset; 4375 u64 alloc_profile; 4376 struct btrfs_fs_info *fs_info = root->fs_info; 4377 struct btrfs_root *extent_root = fs_info->extent_root; 4378 int ret; 4379 4380 chunk_offset = find_next_chunk(fs_info); 4381 alloc_profile = btrfs_get_alloc_profile(extent_root, 0); 4382 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset, 4383 alloc_profile); 4384 if (ret) 4385 return ret; 4386 4387 sys_chunk_offset = find_next_chunk(root->fs_info); 4388 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0); 4389 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset, 4390 alloc_profile); 4391 if (ret) { 4392 btrfs_abort_transaction(trans, root, ret); 4393 goto out; 4394 } 4395 4396 ret = btrfs_add_device(trans, fs_info->chunk_root, device); 4397 if (ret) 4398 btrfs_abort_transaction(trans, root, ret); 4399 out: 4400 return ret; 4401 } 4402 4403 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) 4404 { 4405 struct extent_map *em; 4406 struct map_lookup *map; 4407 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 4408 int readonly = 0; 4409 int i; 4410 4411 read_lock(&map_tree->map_tree.lock); 4412 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); 4413 read_unlock(&map_tree->map_tree.lock); 4414 if (!em) 4415 return 1; 4416 4417 if (btrfs_test_opt(root, DEGRADED)) { 4418 free_extent_map(em); 4419 return 0; 4420 } 4421 4422 map = (struct map_lookup *)em->bdev; 4423 for (i = 0; i < map->num_stripes; i++) { 4424 if (!map->stripes[i].dev->writeable) { 4425 readonly = 1; 4426 break; 4427 } 4428 } 4429 free_extent_map(em); 4430 return readonly; 4431 } 4432 4433 void btrfs_mapping_init(struct btrfs_mapping_tree *tree) 4434 { 4435 extent_map_tree_init(&tree->map_tree); 4436 } 4437 4438 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree) 4439 { 4440 struct extent_map *em; 4441 4442 while (1) { 4443 write_lock(&tree->map_tree.lock); 4444 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1); 4445 if (em) 4446 remove_extent_mapping(&tree->map_tree, em); 4447 write_unlock(&tree->map_tree.lock); 4448 if (!em) 4449 break; 4450 kfree(em->bdev); 4451 /* once for us */ 4452 free_extent_map(em); 4453 /* once for the tree */ 4454 free_extent_map(em); 4455 } 4456 } 4457 4458 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) 4459 { 4460 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4461 struct extent_map *em; 4462 struct map_lookup *map; 4463 struct extent_map_tree *em_tree = &map_tree->map_tree; 4464 int ret; 4465 4466 read_lock(&em_tree->lock); 4467 em = lookup_extent_mapping(em_tree, logical, len); 4468 read_unlock(&em_tree->lock); 4469 4470 /* 4471 * We could return errors for these cases, but that could get ugly and 4472 * we'd probably do the same thing which is just not do anything else 4473 * and exit, so return 1 so the callers don't try to use other copies. 4474 */ 4475 if (!em) { 4476 btrfs_crit(fs_info, "No mapping for %Lu-%Lu\n", logical, 4477 logical+len); 4478 return 1; 4479 } 4480 4481 if (em->start > logical || em->start + em->len < logical) { 4482 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got " 4483 "%Lu-%Lu\n", logical, logical+len, em->start, 4484 em->start + em->len); 4485 return 1; 4486 } 4487 4488 map = (struct map_lookup *)em->bdev; 4489 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1)) 4490 ret = map->num_stripes; 4491 else if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4492 ret = map->sub_stripes; 4493 else if (map->type & BTRFS_BLOCK_GROUP_RAID5) 4494 ret = 2; 4495 else if (map->type & BTRFS_BLOCK_GROUP_RAID6) 4496 ret = 3; 4497 else 4498 ret = 1; 4499 free_extent_map(em); 4500 4501 btrfs_dev_replace_lock(&fs_info->dev_replace); 4502 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) 4503 ret++; 4504 btrfs_dev_replace_unlock(&fs_info->dev_replace); 4505 4506 return ret; 4507 } 4508 4509 unsigned long btrfs_full_stripe_len(struct btrfs_root *root, 4510 struct btrfs_mapping_tree *map_tree, 4511 u64 logical) 4512 { 4513 struct extent_map *em; 4514 struct map_lookup *map; 4515 struct extent_map_tree *em_tree = &map_tree->map_tree; 4516 unsigned long len = root->sectorsize; 4517 4518 read_lock(&em_tree->lock); 4519 em = lookup_extent_mapping(em_tree, logical, len); 4520 read_unlock(&em_tree->lock); 4521 BUG_ON(!em); 4522 4523 BUG_ON(em->start > logical || em->start + em->len < logical); 4524 map = (struct map_lookup *)em->bdev; 4525 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4526 BTRFS_BLOCK_GROUP_RAID6)) { 4527 len = map->stripe_len * nr_data_stripes(map); 4528 } 4529 free_extent_map(em); 4530 return len; 4531 } 4532 4533 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree, 4534 u64 logical, u64 len, int mirror_num) 4535 { 4536 struct extent_map *em; 4537 struct map_lookup *map; 4538 struct extent_map_tree *em_tree = &map_tree->map_tree; 4539 int ret = 0; 4540 4541 read_lock(&em_tree->lock); 4542 em = lookup_extent_mapping(em_tree, logical, len); 4543 read_unlock(&em_tree->lock); 4544 BUG_ON(!em); 4545 4546 BUG_ON(em->start > logical || em->start + em->len < logical); 4547 map = (struct map_lookup *)em->bdev; 4548 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4549 BTRFS_BLOCK_GROUP_RAID6)) 4550 ret = 1; 4551 free_extent_map(em); 4552 return ret; 4553 } 4554 4555 static int find_live_mirror(struct btrfs_fs_info *fs_info, 4556 struct map_lookup *map, int first, int num, 4557 int optimal, int dev_replace_is_ongoing) 4558 { 4559 int i; 4560 int tolerance; 4561 struct btrfs_device *srcdev; 4562 4563 if (dev_replace_is_ongoing && 4564 fs_info->dev_replace.cont_reading_from_srcdev_mode == 4565 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID) 4566 srcdev = fs_info->dev_replace.srcdev; 4567 else 4568 srcdev = NULL; 4569 4570 /* 4571 * try to avoid the drive that is the source drive for a 4572 * dev-replace procedure, only choose it if no other non-missing 4573 * mirror is available 4574 */ 4575 for (tolerance = 0; tolerance < 2; tolerance++) { 4576 if (map->stripes[optimal].dev->bdev && 4577 (tolerance || map->stripes[optimal].dev != srcdev)) 4578 return optimal; 4579 for (i = first; i < first + num; i++) { 4580 if (map->stripes[i].dev->bdev && 4581 (tolerance || map->stripes[i].dev != srcdev)) 4582 return i; 4583 } 4584 } 4585 4586 /* we couldn't find one that doesn't fail. Just return something 4587 * and the io error handling code will clean up eventually 4588 */ 4589 return optimal; 4590 } 4591 4592 static inline int parity_smaller(u64 a, u64 b) 4593 { 4594 return a > b; 4595 } 4596 4597 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */ 4598 static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map) 4599 { 4600 struct btrfs_bio_stripe s; 4601 int i; 4602 u64 l; 4603 int again = 1; 4604 4605 while (again) { 4606 again = 0; 4607 for (i = 0; i < bbio->num_stripes - 1; i++) { 4608 if (parity_smaller(raid_map[i], raid_map[i+1])) { 4609 s = bbio->stripes[i]; 4610 l = raid_map[i]; 4611 bbio->stripes[i] = bbio->stripes[i+1]; 4612 raid_map[i] = raid_map[i+1]; 4613 bbio->stripes[i+1] = s; 4614 raid_map[i+1] = l; 4615 again = 1; 4616 } 4617 } 4618 } 4619 } 4620 4621 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4622 u64 logical, u64 *length, 4623 struct btrfs_bio **bbio_ret, 4624 int mirror_num, u64 **raid_map_ret) 4625 { 4626 struct extent_map *em; 4627 struct map_lookup *map; 4628 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4629 struct extent_map_tree *em_tree = &map_tree->map_tree; 4630 u64 offset; 4631 u64 stripe_offset; 4632 u64 stripe_end_offset; 4633 u64 stripe_nr; 4634 u64 stripe_nr_orig; 4635 u64 stripe_nr_end; 4636 u64 stripe_len; 4637 u64 *raid_map = NULL; 4638 int stripe_index; 4639 int i; 4640 int ret = 0; 4641 int num_stripes; 4642 int max_errors = 0; 4643 struct btrfs_bio *bbio = NULL; 4644 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 4645 int dev_replace_is_ongoing = 0; 4646 int num_alloc_stripes; 4647 int patch_the_first_stripe_for_dev_replace = 0; 4648 u64 physical_to_patch_in_first_stripe = 0; 4649 u64 raid56_full_stripe_start = (u64)-1; 4650 4651 read_lock(&em_tree->lock); 4652 em = lookup_extent_mapping(em_tree, logical, *length); 4653 read_unlock(&em_tree->lock); 4654 4655 if (!em) { 4656 btrfs_crit(fs_info, "unable to find logical %llu len %llu", 4657 logical, *length); 4658 return -EINVAL; 4659 } 4660 4661 if (em->start > logical || em->start + em->len < logical) { 4662 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, " 4663 "found %Lu-%Lu\n", logical, em->start, 4664 em->start + em->len); 4665 return -EINVAL; 4666 } 4667 4668 map = (struct map_lookup *)em->bdev; 4669 offset = logical - em->start; 4670 4671 stripe_len = map->stripe_len; 4672 stripe_nr = offset; 4673 /* 4674 * stripe_nr counts the total number of stripes we have to stride 4675 * to get to this block 4676 */ 4677 do_div(stripe_nr, stripe_len); 4678 4679 stripe_offset = stripe_nr * stripe_len; 4680 BUG_ON(offset < stripe_offset); 4681 4682 /* stripe_offset is the offset of this block in its stripe*/ 4683 stripe_offset = offset - stripe_offset; 4684 4685 /* if we're here for raid56, we need to know the stripe aligned start */ 4686 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { 4687 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map); 4688 raid56_full_stripe_start = offset; 4689 4690 /* allow a write of a full stripe, but make sure we don't 4691 * allow straddling of stripes 4692 */ 4693 do_div(raid56_full_stripe_start, full_stripe_len); 4694 raid56_full_stripe_start *= full_stripe_len; 4695 } 4696 4697 if (rw & REQ_DISCARD) { 4698 /* we don't discard raid56 yet */ 4699 if (map->type & 4700 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { 4701 ret = -EOPNOTSUPP; 4702 goto out; 4703 } 4704 *length = min_t(u64, em->len - offset, *length); 4705 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { 4706 u64 max_len; 4707 /* For writes to RAID[56], allow a full stripeset across all disks. 4708 For other RAID types and for RAID[56] reads, just allow a single 4709 stripe (on a single disk). */ 4710 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6) && 4711 (rw & REQ_WRITE)) { 4712 max_len = stripe_len * nr_data_stripes(map) - 4713 (offset - raid56_full_stripe_start); 4714 } else { 4715 /* we limit the length of each bio to what fits in a stripe */ 4716 max_len = stripe_len - stripe_offset; 4717 } 4718 *length = min_t(u64, em->len - offset, max_len); 4719 } else { 4720 *length = em->len - offset; 4721 } 4722 4723 /* This is for when we're called from btrfs_merge_bio_hook() and all 4724 it cares about is the length */ 4725 if (!bbio_ret) 4726 goto out; 4727 4728 btrfs_dev_replace_lock(dev_replace); 4729 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace); 4730 if (!dev_replace_is_ongoing) 4731 btrfs_dev_replace_unlock(dev_replace); 4732 4733 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 && 4734 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) && 4735 dev_replace->tgtdev != NULL) { 4736 /* 4737 * in dev-replace case, for repair case (that's the only 4738 * case where the mirror is selected explicitly when 4739 * calling btrfs_map_block), blocks left of the left cursor 4740 * can also be read from the target drive. 4741 * For REQ_GET_READ_MIRRORS, the target drive is added as 4742 * the last one to the array of stripes. For READ, it also 4743 * needs to be supported using the same mirror number. 4744 * If the requested block is not left of the left cursor, 4745 * EIO is returned. This can happen because btrfs_num_copies() 4746 * returns one more in the dev-replace case. 4747 */ 4748 u64 tmp_length = *length; 4749 struct btrfs_bio *tmp_bbio = NULL; 4750 int tmp_num_stripes; 4751 u64 srcdev_devid = dev_replace->srcdev->devid; 4752 int index_srcdev = 0; 4753 int found = 0; 4754 u64 physical_of_found = 0; 4755 4756 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, 4757 logical, &tmp_length, &tmp_bbio, 0, NULL); 4758 if (ret) { 4759 WARN_ON(tmp_bbio != NULL); 4760 goto out; 4761 } 4762 4763 tmp_num_stripes = tmp_bbio->num_stripes; 4764 if (mirror_num > tmp_num_stripes) { 4765 /* 4766 * REQ_GET_READ_MIRRORS does not contain this 4767 * mirror, that means that the requested area 4768 * is not left of the left cursor 4769 */ 4770 ret = -EIO; 4771 kfree(tmp_bbio); 4772 goto out; 4773 } 4774 4775 /* 4776 * process the rest of the function using the mirror_num 4777 * of the source drive. Therefore look it up first. 4778 * At the end, patch the device pointer to the one of the 4779 * target drive. 4780 */ 4781 for (i = 0; i < tmp_num_stripes; i++) { 4782 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) { 4783 /* 4784 * In case of DUP, in order to keep it 4785 * simple, only add the mirror with the 4786 * lowest physical address 4787 */ 4788 if (found && 4789 physical_of_found <= 4790 tmp_bbio->stripes[i].physical) 4791 continue; 4792 index_srcdev = i; 4793 found = 1; 4794 physical_of_found = 4795 tmp_bbio->stripes[i].physical; 4796 } 4797 } 4798 4799 if (found) { 4800 mirror_num = index_srcdev + 1; 4801 patch_the_first_stripe_for_dev_replace = 1; 4802 physical_to_patch_in_first_stripe = physical_of_found; 4803 } else { 4804 WARN_ON(1); 4805 ret = -EIO; 4806 kfree(tmp_bbio); 4807 goto out; 4808 } 4809 4810 kfree(tmp_bbio); 4811 } else if (mirror_num > map->num_stripes) { 4812 mirror_num = 0; 4813 } 4814 4815 num_stripes = 1; 4816 stripe_index = 0; 4817 stripe_nr_orig = stripe_nr; 4818 stripe_nr_end = ALIGN(offset + *length, map->stripe_len); 4819 do_div(stripe_nr_end, map->stripe_len); 4820 stripe_end_offset = stripe_nr_end * map->stripe_len - 4821 (offset + *length); 4822 4823 if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4824 if (rw & REQ_DISCARD) 4825 num_stripes = min_t(u64, map->num_stripes, 4826 stripe_nr_end - stripe_nr_orig); 4827 stripe_index = do_div(stripe_nr, map->num_stripes); 4828 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { 4829 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) 4830 num_stripes = map->num_stripes; 4831 else if (mirror_num) 4832 stripe_index = mirror_num - 1; 4833 else { 4834 stripe_index = find_live_mirror(fs_info, map, 0, 4835 map->num_stripes, 4836 current->pid % map->num_stripes, 4837 dev_replace_is_ongoing); 4838 mirror_num = stripe_index + 1; 4839 } 4840 4841 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { 4842 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) { 4843 num_stripes = map->num_stripes; 4844 } else if (mirror_num) { 4845 stripe_index = mirror_num - 1; 4846 } else { 4847 mirror_num = 1; 4848 } 4849 4850 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4851 int factor = map->num_stripes / map->sub_stripes; 4852 4853 stripe_index = do_div(stripe_nr, factor); 4854 stripe_index *= map->sub_stripes; 4855 4856 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) 4857 num_stripes = map->sub_stripes; 4858 else if (rw & REQ_DISCARD) 4859 num_stripes = min_t(u64, map->sub_stripes * 4860 (stripe_nr_end - stripe_nr_orig), 4861 map->num_stripes); 4862 else if (mirror_num) 4863 stripe_index += mirror_num - 1; 4864 else { 4865 int old_stripe_index = stripe_index; 4866 stripe_index = find_live_mirror(fs_info, map, 4867 stripe_index, 4868 map->sub_stripes, stripe_index + 4869 current->pid % map->sub_stripes, 4870 dev_replace_is_ongoing); 4871 mirror_num = stripe_index - old_stripe_index + 1; 4872 } 4873 4874 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4875 BTRFS_BLOCK_GROUP_RAID6)) { 4876 u64 tmp; 4877 4878 if (bbio_ret && ((rw & REQ_WRITE) || mirror_num > 1) 4879 && raid_map_ret) { 4880 int i, rot; 4881 4882 /* push stripe_nr back to the start of the full stripe */ 4883 stripe_nr = raid56_full_stripe_start; 4884 do_div(stripe_nr, stripe_len); 4885 4886 stripe_index = do_div(stripe_nr, nr_data_stripes(map)); 4887 4888 /* RAID[56] write or recovery. Return all stripes */ 4889 num_stripes = map->num_stripes; 4890 max_errors = nr_parity_stripes(map); 4891 4892 raid_map = kmalloc(sizeof(u64) * num_stripes, 4893 GFP_NOFS); 4894 if (!raid_map) { 4895 ret = -ENOMEM; 4896 goto out; 4897 } 4898 4899 /* Work out the disk rotation on this stripe-set */ 4900 tmp = stripe_nr; 4901 rot = do_div(tmp, num_stripes); 4902 4903 /* Fill in the logical address of each stripe */ 4904 tmp = stripe_nr * nr_data_stripes(map); 4905 for (i = 0; i < nr_data_stripes(map); i++) 4906 raid_map[(i+rot) % num_stripes] = 4907 em->start + (tmp + i) * map->stripe_len; 4908 4909 raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE; 4910 if (map->type & BTRFS_BLOCK_GROUP_RAID6) 4911 raid_map[(i+rot+1) % num_stripes] = 4912 RAID6_Q_STRIPE; 4913 4914 *length = map->stripe_len; 4915 stripe_index = 0; 4916 stripe_offset = 0; 4917 } else { 4918 /* 4919 * Mirror #0 or #1 means the original data block. 4920 * Mirror #2 is RAID5 parity block. 4921 * Mirror #3 is RAID6 Q block. 4922 */ 4923 stripe_index = do_div(stripe_nr, nr_data_stripes(map)); 4924 if (mirror_num > 1) 4925 stripe_index = nr_data_stripes(map) + 4926 mirror_num - 2; 4927 4928 /* We distribute the parity blocks across stripes */ 4929 tmp = stripe_nr + stripe_index; 4930 stripe_index = do_div(tmp, map->num_stripes); 4931 } 4932 } else { 4933 /* 4934 * after this do_div call, stripe_nr is the number of stripes 4935 * on this device we have to walk to find the data, and 4936 * stripe_index is the number of our device in the stripe array 4937 */ 4938 stripe_index = do_div(stripe_nr, map->num_stripes); 4939 mirror_num = stripe_index + 1; 4940 } 4941 BUG_ON(stripe_index >= map->num_stripes); 4942 4943 num_alloc_stripes = num_stripes; 4944 if (dev_replace_is_ongoing) { 4945 if (rw & (REQ_WRITE | REQ_DISCARD)) 4946 num_alloc_stripes <<= 1; 4947 if (rw & REQ_GET_READ_MIRRORS) 4948 num_alloc_stripes++; 4949 } 4950 bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS); 4951 if (!bbio) { 4952 kfree(raid_map); 4953 ret = -ENOMEM; 4954 goto out; 4955 } 4956 atomic_set(&bbio->error, 0); 4957 4958 if (rw & REQ_DISCARD) { 4959 int factor = 0; 4960 int sub_stripes = 0; 4961 u64 stripes_per_dev = 0; 4962 u32 remaining_stripes = 0; 4963 u32 last_stripe = 0; 4964 4965 if (map->type & 4966 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { 4967 if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4968 sub_stripes = 1; 4969 else 4970 sub_stripes = map->sub_stripes; 4971 4972 factor = map->num_stripes / sub_stripes; 4973 stripes_per_dev = div_u64_rem(stripe_nr_end - 4974 stripe_nr_orig, 4975 factor, 4976 &remaining_stripes); 4977 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe); 4978 last_stripe *= sub_stripes; 4979 } 4980 4981 for (i = 0; i < num_stripes; i++) { 4982 bbio->stripes[i].physical = 4983 map->stripes[stripe_index].physical + 4984 stripe_offset + stripe_nr * map->stripe_len; 4985 bbio->stripes[i].dev = map->stripes[stripe_index].dev; 4986 4987 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | 4988 BTRFS_BLOCK_GROUP_RAID10)) { 4989 bbio->stripes[i].length = stripes_per_dev * 4990 map->stripe_len; 4991 4992 if (i / sub_stripes < remaining_stripes) 4993 bbio->stripes[i].length += 4994 map->stripe_len; 4995 4996 /* 4997 * Special for the first stripe and 4998 * the last stripe: 4999 * 5000 * |-------|...|-------| 5001 * |----------| 5002 * off end_off 5003 */ 5004 if (i < sub_stripes) 5005 bbio->stripes[i].length -= 5006 stripe_offset; 5007 5008 if (stripe_index >= last_stripe && 5009 stripe_index <= (last_stripe + 5010 sub_stripes - 1)) 5011 bbio->stripes[i].length -= 5012 stripe_end_offset; 5013 5014 if (i == sub_stripes - 1) 5015 stripe_offset = 0; 5016 } else 5017 bbio->stripes[i].length = *length; 5018 5019 stripe_index++; 5020 if (stripe_index == map->num_stripes) { 5021 /* This could only happen for RAID0/10 */ 5022 stripe_index = 0; 5023 stripe_nr++; 5024 } 5025 } 5026 } else { 5027 for (i = 0; i < num_stripes; i++) { 5028 bbio->stripes[i].physical = 5029 map->stripes[stripe_index].physical + 5030 stripe_offset + 5031 stripe_nr * map->stripe_len; 5032 bbio->stripes[i].dev = 5033 map->stripes[stripe_index].dev; 5034 stripe_index++; 5035 } 5036 } 5037 5038 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) { 5039 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | 5040 BTRFS_BLOCK_GROUP_RAID10 | 5041 BTRFS_BLOCK_GROUP_RAID5 | 5042 BTRFS_BLOCK_GROUP_DUP)) { 5043 max_errors = 1; 5044 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) { 5045 max_errors = 2; 5046 } 5047 } 5048 5049 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) && 5050 dev_replace->tgtdev != NULL) { 5051 int index_where_to_add; 5052 u64 srcdev_devid = dev_replace->srcdev->devid; 5053 5054 /* 5055 * duplicate the write operations while the dev replace 5056 * procedure is running. Since the copying of the old disk 5057 * to the new disk takes place at run time while the 5058 * filesystem is mounted writable, the regular write 5059 * operations to the old disk have to be duplicated to go 5060 * to the new disk as well. 5061 * Note that device->missing is handled by the caller, and 5062 * that the write to the old disk is already set up in the 5063 * stripes array. 5064 */ 5065 index_where_to_add = num_stripes; 5066 for (i = 0; i < num_stripes; i++) { 5067 if (bbio->stripes[i].dev->devid == srcdev_devid) { 5068 /* write to new disk, too */ 5069 struct btrfs_bio_stripe *new = 5070 bbio->stripes + index_where_to_add; 5071 struct btrfs_bio_stripe *old = 5072 bbio->stripes + i; 5073 5074 new->physical = old->physical; 5075 new->length = old->length; 5076 new->dev = dev_replace->tgtdev; 5077 index_where_to_add++; 5078 max_errors++; 5079 } 5080 } 5081 num_stripes = index_where_to_add; 5082 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) && 5083 dev_replace->tgtdev != NULL) { 5084 u64 srcdev_devid = dev_replace->srcdev->devid; 5085 int index_srcdev = 0; 5086 int found = 0; 5087 u64 physical_of_found = 0; 5088 5089 /* 5090 * During the dev-replace procedure, the target drive can 5091 * also be used to read data in case it is needed to repair 5092 * a corrupt block elsewhere. This is possible if the 5093 * requested area is left of the left cursor. In this area, 5094 * the target drive is a full copy of the source drive. 5095 */ 5096 for (i = 0; i < num_stripes; i++) { 5097 if (bbio->stripes[i].dev->devid == srcdev_devid) { 5098 /* 5099 * In case of DUP, in order to keep it 5100 * simple, only add the mirror with the 5101 * lowest physical address 5102 */ 5103 if (found && 5104 physical_of_found <= 5105 bbio->stripes[i].physical) 5106 continue; 5107 index_srcdev = i; 5108 found = 1; 5109 physical_of_found = bbio->stripes[i].physical; 5110 } 5111 } 5112 if (found) { 5113 u64 length = map->stripe_len; 5114 5115 if (physical_of_found + length <= 5116 dev_replace->cursor_left) { 5117 struct btrfs_bio_stripe *tgtdev_stripe = 5118 bbio->stripes + num_stripes; 5119 5120 tgtdev_stripe->physical = physical_of_found; 5121 tgtdev_stripe->length = 5122 bbio->stripes[index_srcdev].length; 5123 tgtdev_stripe->dev = dev_replace->tgtdev; 5124 5125 num_stripes++; 5126 } 5127 } 5128 } 5129 5130 *bbio_ret = bbio; 5131 bbio->num_stripes = num_stripes; 5132 bbio->max_errors = max_errors; 5133 bbio->mirror_num = mirror_num; 5134 5135 /* 5136 * this is the case that REQ_READ && dev_replace_is_ongoing && 5137 * mirror_num == num_stripes + 1 && dev_replace target drive is 5138 * available as a mirror 5139 */ 5140 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) { 5141 WARN_ON(num_stripes > 1); 5142 bbio->stripes[0].dev = dev_replace->tgtdev; 5143 bbio->stripes[0].physical = physical_to_patch_in_first_stripe; 5144 bbio->mirror_num = map->num_stripes + 1; 5145 } 5146 if (raid_map) { 5147 sort_parity_stripes(bbio, raid_map); 5148 *raid_map_ret = raid_map; 5149 } 5150 out: 5151 if (dev_replace_is_ongoing) 5152 btrfs_dev_replace_unlock(dev_replace); 5153 free_extent_map(em); 5154 return ret; 5155 } 5156 5157 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 5158 u64 logical, u64 *length, 5159 struct btrfs_bio **bbio_ret, int mirror_num) 5160 { 5161 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret, 5162 mirror_num, NULL); 5163 } 5164 5165 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, 5166 u64 chunk_start, u64 physical, u64 devid, 5167 u64 **logical, int *naddrs, int *stripe_len) 5168 { 5169 struct extent_map_tree *em_tree = &map_tree->map_tree; 5170 struct extent_map *em; 5171 struct map_lookup *map; 5172 u64 *buf; 5173 u64 bytenr; 5174 u64 length; 5175 u64 stripe_nr; 5176 u64 rmap_len; 5177 int i, j, nr = 0; 5178 5179 read_lock(&em_tree->lock); 5180 em = lookup_extent_mapping(em_tree, chunk_start, 1); 5181 read_unlock(&em_tree->lock); 5182 5183 if (!em) { 5184 printk(KERN_ERR "btrfs: couldn't find em for chunk %Lu\n", 5185 chunk_start); 5186 return -EIO; 5187 } 5188 5189 if (em->start != chunk_start) { 5190 printk(KERN_ERR "btrfs: bad chunk start, em=%Lu, wanted=%Lu\n", 5191 em->start, chunk_start); 5192 free_extent_map(em); 5193 return -EIO; 5194 } 5195 map = (struct map_lookup *)em->bdev; 5196 5197 length = em->len; 5198 rmap_len = map->stripe_len; 5199 5200 if (map->type & BTRFS_BLOCK_GROUP_RAID10) 5201 do_div(length, map->num_stripes / map->sub_stripes); 5202 else if (map->type & BTRFS_BLOCK_GROUP_RAID0) 5203 do_div(length, map->num_stripes); 5204 else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 5205 BTRFS_BLOCK_GROUP_RAID6)) { 5206 do_div(length, nr_data_stripes(map)); 5207 rmap_len = map->stripe_len * nr_data_stripes(map); 5208 } 5209 5210 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); 5211 BUG_ON(!buf); /* -ENOMEM */ 5212 5213 for (i = 0; i < map->num_stripes; i++) { 5214 if (devid && map->stripes[i].dev->devid != devid) 5215 continue; 5216 if (map->stripes[i].physical > physical || 5217 map->stripes[i].physical + length <= physical) 5218 continue; 5219 5220 stripe_nr = physical - map->stripes[i].physical; 5221 do_div(stripe_nr, map->stripe_len); 5222 5223 if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 5224 stripe_nr = stripe_nr * map->num_stripes + i; 5225 do_div(stripe_nr, map->sub_stripes); 5226 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 5227 stripe_nr = stripe_nr * map->num_stripes + i; 5228 } /* else if RAID[56], multiply by nr_data_stripes(). 5229 * Alternatively, just use rmap_len below instead of 5230 * map->stripe_len */ 5231 5232 bytenr = chunk_start + stripe_nr * rmap_len; 5233 WARN_ON(nr >= map->num_stripes); 5234 for (j = 0; j < nr; j++) { 5235 if (buf[j] == bytenr) 5236 break; 5237 } 5238 if (j == nr) { 5239 WARN_ON(nr >= map->num_stripes); 5240 buf[nr++] = bytenr; 5241 } 5242 } 5243 5244 *logical = buf; 5245 *naddrs = nr; 5246 *stripe_len = rmap_len; 5247 5248 free_extent_map(em); 5249 return 0; 5250 } 5251 5252 static void btrfs_end_bio(struct bio *bio, int err) 5253 { 5254 struct btrfs_bio *bbio = bio->bi_private; 5255 int is_orig_bio = 0; 5256 5257 if (err) { 5258 atomic_inc(&bbio->error); 5259 if (err == -EIO || err == -EREMOTEIO) { 5260 unsigned int stripe_index = 5261 btrfs_io_bio(bio)->stripe_index; 5262 struct btrfs_device *dev; 5263 5264 BUG_ON(stripe_index >= bbio->num_stripes); 5265 dev = bbio->stripes[stripe_index].dev; 5266 if (dev->bdev) { 5267 if (bio->bi_rw & WRITE) 5268 btrfs_dev_stat_inc(dev, 5269 BTRFS_DEV_STAT_WRITE_ERRS); 5270 else 5271 btrfs_dev_stat_inc(dev, 5272 BTRFS_DEV_STAT_READ_ERRS); 5273 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH) 5274 btrfs_dev_stat_inc(dev, 5275 BTRFS_DEV_STAT_FLUSH_ERRS); 5276 btrfs_dev_stat_print_on_error(dev); 5277 } 5278 } 5279 } 5280 5281 if (bio == bbio->orig_bio) 5282 is_orig_bio = 1; 5283 5284 if (atomic_dec_and_test(&bbio->stripes_pending)) { 5285 if (!is_orig_bio) { 5286 bio_put(bio); 5287 bio = bbio->orig_bio; 5288 } 5289 bio->bi_private = bbio->private; 5290 bio->bi_end_io = bbio->end_io; 5291 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num; 5292 /* only send an error to the higher layers if it is 5293 * beyond the tolerance of the btrfs bio 5294 */ 5295 if (atomic_read(&bbio->error) > bbio->max_errors) { 5296 err = -EIO; 5297 } else { 5298 /* 5299 * this bio is actually up to date, we didn't 5300 * go over the max number of errors 5301 */ 5302 set_bit(BIO_UPTODATE, &bio->bi_flags); 5303 err = 0; 5304 } 5305 kfree(bbio); 5306 5307 bio_endio(bio, err); 5308 } else if (!is_orig_bio) { 5309 bio_put(bio); 5310 } 5311 } 5312 5313 struct async_sched { 5314 struct bio *bio; 5315 int rw; 5316 struct btrfs_fs_info *info; 5317 struct btrfs_work work; 5318 }; 5319 5320 /* 5321 * see run_scheduled_bios for a description of why bios are collected for 5322 * async submit. 5323 * 5324 * This will add one bio to the pending list for a device and make sure 5325 * the work struct is scheduled. 5326 */ 5327 static noinline void btrfs_schedule_bio(struct btrfs_root *root, 5328 struct btrfs_device *device, 5329 int rw, struct bio *bio) 5330 { 5331 int should_queue = 1; 5332 struct btrfs_pending_bios *pending_bios; 5333 5334 if (device->missing || !device->bdev) { 5335 bio_endio(bio, -EIO); 5336 return; 5337 } 5338 5339 /* don't bother with additional async steps for reads, right now */ 5340 if (!(rw & REQ_WRITE)) { 5341 bio_get(bio); 5342 btrfsic_submit_bio(rw, bio); 5343 bio_put(bio); 5344 return; 5345 } 5346 5347 /* 5348 * nr_async_bios allows us to reliably return congestion to the 5349 * higher layers. Otherwise, the async bio makes it appear we have 5350 * made progress against dirty pages when we've really just put it 5351 * on a queue for later 5352 */ 5353 atomic_inc(&root->fs_info->nr_async_bios); 5354 WARN_ON(bio->bi_next); 5355 bio->bi_next = NULL; 5356 bio->bi_rw |= rw; 5357 5358 spin_lock(&device->io_lock); 5359 if (bio->bi_rw & REQ_SYNC) 5360 pending_bios = &device->pending_sync_bios; 5361 else 5362 pending_bios = &device->pending_bios; 5363 5364 if (pending_bios->tail) 5365 pending_bios->tail->bi_next = bio; 5366 5367 pending_bios->tail = bio; 5368 if (!pending_bios->head) 5369 pending_bios->head = bio; 5370 if (device->running_pending) 5371 should_queue = 0; 5372 5373 spin_unlock(&device->io_lock); 5374 5375 if (should_queue) 5376 btrfs_queue_worker(&root->fs_info->submit_workers, 5377 &device->work); 5378 } 5379 5380 static int bio_size_ok(struct block_device *bdev, struct bio *bio, 5381 sector_t sector) 5382 { 5383 struct bio_vec *prev; 5384 struct request_queue *q = bdev_get_queue(bdev); 5385 unsigned short max_sectors = queue_max_sectors(q); 5386 struct bvec_merge_data bvm = { 5387 .bi_bdev = bdev, 5388 .bi_sector = sector, 5389 .bi_rw = bio->bi_rw, 5390 }; 5391 5392 if (bio->bi_vcnt == 0) { 5393 WARN_ON(1); 5394 return 1; 5395 } 5396 5397 prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; 5398 if (bio_sectors(bio) > max_sectors) 5399 return 0; 5400 5401 if (!q->merge_bvec_fn) 5402 return 1; 5403 5404 bvm.bi_size = bio->bi_size - prev->bv_len; 5405 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) 5406 return 0; 5407 return 1; 5408 } 5409 5410 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 5411 struct bio *bio, u64 physical, int dev_nr, 5412 int rw, int async) 5413 { 5414 struct btrfs_device *dev = bbio->stripes[dev_nr].dev; 5415 5416 bio->bi_private = bbio; 5417 btrfs_io_bio(bio)->stripe_index = dev_nr; 5418 bio->bi_end_io = btrfs_end_bio; 5419 bio->bi_sector = physical >> 9; 5420 #ifdef DEBUG 5421 { 5422 struct rcu_string *name; 5423 5424 rcu_read_lock(); 5425 name = rcu_dereference(dev->name); 5426 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu " 5427 "(%s id %llu), size=%u\n", rw, 5428 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, 5429 name->str, dev->devid, bio->bi_size); 5430 rcu_read_unlock(); 5431 } 5432 #endif 5433 bio->bi_bdev = dev->bdev; 5434 if (async) 5435 btrfs_schedule_bio(root, dev, rw, bio); 5436 else 5437 btrfsic_submit_bio(rw, bio); 5438 } 5439 5440 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 5441 struct bio *first_bio, struct btrfs_device *dev, 5442 int dev_nr, int rw, int async) 5443 { 5444 struct bio_vec *bvec = first_bio->bi_io_vec; 5445 struct bio *bio; 5446 int nr_vecs = bio_get_nr_vecs(dev->bdev); 5447 u64 physical = bbio->stripes[dev_nr].physical; 5448 5449 again: 5450 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS); 5451 if (!bio) 5452 return -ENOMEM; 5453 5454 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) { 5455 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len, 5456 bvec->bv_offset) < bvec->bv_len) { 5457 u64 len = bio->bi_size; 5458 5459 atomic_inc(&bbio->stripes_pending); 5460 submit_stripe_bio(root, bbio, bio, physical, dev_nr, 5461 rw, async); 5462 physical += len; 5463 goto again; 5464 } 5465 bvec++; 5466 } 5467 5468 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async); 5469 return 0; 5470 } 5471 5472 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) 5473 { 5474 atomic_inc(&bbio->error); 5475 if (atomic_dec_and_test(&bbio->stripes_pending)) { 5476 bio->bi_private = bbio->private; 5477 bio->bi_end_io = bbio->end_io; 5478 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num; 5479 bio->bi_sector = logical >> 9; 5480 kfree(bbio); 5481 bio_endio(bio, -EIO); 5482 } 5483 } 5484 5485 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, 5486 int mirror_num, int async_submit) 5487 { 5488 struct btrfs_device *dev; 5489 struct bio *first_bio = bio; 5490 u64 logical = (u64)bio->bi_sector << 9; 5491 u64 length = 0; 5492 u64 map_length; 5493 u64 *raid_map = NULL; 5494 int ret; 5495 int dev_nr = 0; 5496 int total_devs = 1; 5497 struct btrfs_bio *bbio = NULL; 5498 5499 length = bio->bi_size; 5500 map_length = length; 5501 5502 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio, 5503 mirror_num, &raid_map); 5504 if (ret) /* -ENOMEM */ 5505 return ret; 5506 5507 total_devs = bbio->num_stripes; 5508 bbio->orig_bio = first_bio; 5509 bbio->private = first_bio->bi_private; 5510 bbio->end_io = first_bio->bi_end_io; 5511 atomic_set(&bbio->stripes_pending, bbio->num_stripes); 5512 5513 if (raid_map) { 5514 /* In this case, map_length has been set to the length of 5515 a single stripe; not the whole write */ 5516 if (rw & WRITE) { 5517 return raid56_parity_write(root, bio, bbio, 5518 raid_map, map_length); 5519 } else { 5520 return raid56_parity_recover(root, bio, bbio, 5521 raid_map, map_length, 5522 mirror_num); 5523 } 5524 } 5525 5526 if (map_length < length) { 5527 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu", 5528 logical, length, map_length); 5529 BUG(); 5530 } 5531 5532 while (dev_nr < total_devs) { 5533 dev = bbio->stripes[dev_nr].dev; 5534 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) { 5535 bbio_error(bbio, first_bio, logical); 5536 dev_nr++; 5537 continue; 5538 } 5539 5540 /* 5541 * Check and see if we're ok with this bio based on it's size 5542 * and offset with the given device. 5543 */ 5544 if (!bio_size_ok(dev->bdev, first_bio, 5545 bbio->stripes[dev_nr].physical >> 9)) { 5546 ret = breakup_stripe_bio(root, bbio, first_bio, dev, 5547 dev_nr, rw, async_submit); 5548 BUG_ON(ret); 5549 dev_nr++; 5550 continue; 5551 } 5552 5553 if (dev_nr < total_devs - 1) { 5554 bio = btrfs_bio_clone(first_bio, GFP_NOFS); 5555 BUG_ON(!bio); /* -ENOMEM */ 5556 } else { 5557 bio = first_bio; 5558 } 5559 5560 submit_stripe_bio(root, bbio, bio, 5561 bbio->stripes[dev_nr].physical, dev_nr, rw, 5562 async_submit); 5563 dev_nr++; 5564 } 5565 return 0; 5566 } 5567 5568 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, 5569 u8 *uuid, u8 *fsid) 5570 { 5571 struct btrfs_device *device; 5572 struct btrfs_fs_devices *cur_devices; 5573 5574 cur_devices = fs_info->fs_devices; 5575 while (cur_devices) { 5576 if (!fsid || 5577 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5578 device = __find_device(&cur_devices->devices, 5579 devid, uuid); 5580 if (device) 5581 return device; 5582 } 5583 cur_devices = cur_devices->seed; 5584 } 5585 return NULL; 5586 } 5587 5588 static struct btrfs_device *add_missing_dev(struct btrfs_root *root, 5589 u64 devid, u8 *dev_uuid) 5590 { 5591 struct btrfs_device *device; 5592 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5593 5594 device = btrfs_alloc_device(NULL, &devid, dev_uuid); 5595 if (IS_ERR(device)) 5596 return NULL; 5597 5598 list_add(&device->dev_list, &fs_devices->devices); 5599 device->fs_devices = fs_devices; 5600 fs_devices->num_devices++; 5601 5602 device->missing = 1; 5603 fs_devices->missing_devices++; 5604 5605 return device; 5606 } 5607 5608 /** 5609 * btrfs_alloc_device - allocate struct btrfs_device 5610 * @fs_info: used only for generating a new devid, can be NULL if 5611 * devid is provided (i.e. @devid != NULL). 5612 * @devid: a pointer to devid for this device. If NULL a new devid 5613 * is generated. 5614 * @uuid: a pointer to UUID for this device. If NULL a new UUID 5615 * is generated. 5616 * 5617 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR() 5618 * on error. Returned struct is not linked onto any lists and can be 5619 * destroyed with kfree() right away. 5620 */ 5621 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info, 5622 const u64 *devid, 5623 const u8 *uuid) 5624 { 5625 struct btrfs_device *dev; 5626 u64 tmp; 5627 5628 if (!devid && !fs_info) { 5629 WARN_ON(1); 5630 return ERR_PTR(-EINVAL); 5631 } 5632 5633 dev = __alloc_device(); 5634 if (IS_ERR(dev)) 5635 return dev; 5636 5637 if (devid) 5638 tmp = *devid; 5639 else { 5640 int ret; 5641 5642 ret = find_next_devid(fs_info, &tmp); 5643 if (ret) { 5644 kfree(dev); 5645 return ERR_PTR(ret); 5646 } 5647 } 5648 dev->devid = tmp; 5649 5650 if (uuid) 5651 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE); 5652 else 5653 generate_random_uuid(dev->uuid); 5654 5655 dev->work.func = pending_bios_fn; 5656 5657 return dev; 5658 } 5659 5660 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, 5661 struct extent_buffer *leaf, 5662 struct btrfs_chunk *chunk) 5663 { 5664 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 5665 struct map_lookup *map; 5666 struct extent_map *em; 5667 u64 logical; 5668 u64 length; 5669 u64 devid; 5670 u8 uuid[BTRFS_UUID_SIZE]; 5671 int num_stripes; 5672 int ret; 5673 int i; 5674 5675 logical = key->offset; 5676 length = btrfs_chunk_length(leaf, chunk); 5677 5678 read_lock(&map_tree->map_tree.lock); 5679 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1); 5680 read_unlock(&map_tree->map_tree.lock); 5681 5682 /* already mapped? */ 5683 if (em && em->start <= logical && em->start + em->len > logical) { 5684 free_extent_map(em); 5685 return 0; 5686 } else if (em) { 5687 free_extent_map(em); 5688 } 5689 5690 em = alloc_extent_map(); 5691 if (!em) 5692 return -ENOMEM; 5693 num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 5694 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 5695 if (!map) { 5696 free_extent_map(em); 5697 return -ENOMEM; 5698 } 5699 5700 em->bdev = (struct block_device *)map; 5701 em->start = logical; 5702 em->len = length; 5703 em->orig_start = 0; 5704 em->block_start = 0; 5705 em->block_len = em->len; 5706 5707 map->num_stripes = num_stripes; 5708 map->io_width = btrfs_chunk_io_width(leaf, chunk); 5709 map->io_align = btrfs_chunk_io_align(leaf, chunk); 5710 map->sector_size = btrfs_chunk_sector_size(leaf, chunk); 5711 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); 5712 map->type = btrfs_chunk_type(leaf, chunk); 5713 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); 5714 for (i = 0; i < num_stripes; i++) { 5715 map->stripes[i].physical = 5716 btrfs_stripe_offset_nr(leaf, chunk, i); 5717 devid = btrfs_stripe_devid_nr(leaf, chunk, i); 5718 read_extent_buffer(leaf, uuid, (unsigned long) 5719 btrfs_stripe_dev_uuid_nr(chunk, i), 5720 BTRFS_UUID_SIZE); 5721 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid, 5722 uuid, NULL); 5723 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) { 5724 kfree(map); 5725 free_extent_map(em); 5726 return -EIO; 5727 } 5728 if (!map->stripes[i].dev) { 5729 map->stripes[i].dev = 5730 add_missing_dev(root, devid, uuid); 5731 if (!map->stripes[i].dev) { 5732 kfree(map); 5733 free_extent_map(em); 5734 return -EIO; 5735 } 5736 } 5737 map->stripes[i].dev->in_fs_metadata = 1; 5738 } 5739 5740 write_lock(&map_tree->map_tree.lock); 5741 ret = add_extent_mapping(&map_tree->map_tree, em, 0); 5742 write_unlock(&map_tree->map_tree.lock); 5743 BUG_ON(ret); /* Tree corruption */ 5744 free_extent_map(em); 5745 5746 return 0; 5747 } 5748 5749 static void fill_device_from_item(struct extent_buffer *leaf, 5750 struct btrfs_dev_item *dev_item, 5751 struct btrfs_device *device) 5752 { 5753 unsigned long ptr; 5754 5755 device->devid = btrfs_device_id(leaf, dev_item); 5756 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); 5757 device->total_bytes = device->disk_total_bytes; 5758 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); 5759 device->type = btrfs_device_type(leaf, dev_item); 5760 device->io_align = btrfs_device_io_align(leaf, dev_item); 5761 device->io_width = btrfs_device_io_width(leaf, dev_item); 5762 device->sector_size = btrfs_device_sector_size(leaf, dev_item); 5763 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); 5764 device->is_tgtdev_for_dev_replace = 0; 5765 5766 ptr = btrfs_device_uuid(dev_item); 5767 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 5768 } 5769 5770 static int open_seed_devices(struct btrfs_root *root, u8 *fsid) 5771 { 5772 struct btrfs_fs_devices *fs_devices; 5773 int ret; 5774 5775 BUG_ON(!mutex_is_locked(&uuid_mutex)); 5776 5777 fs_devices = root->fs_info->fs_devices->seed; 5778 while (fs_devices) { 5779 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5780 ret = 0; 5781 goto out; 5782 } 5783 fs_devices = fs_devices->seed; 5784 } 5785 5786 fs_devices = find_fsid(fsid); 5787 if (!fs_devices) { 5788 ret = -ENOENT; 5789 goto out; 5790 } 5791 5792 fs_devices = clone_fs_devices(fs_devices); 5793 if (IS_ERR(fs_devices)) { 5794 ret = PTR_ERR(fs_devices); 5795 goto out; 5796 } 5797 5798 ret = __btrfs_open_devices(fs_devices, FMODE_READ, 5799 root->fs_info->bdev_holder); 5800 if (ret) { 5801 free_fs_devices(fs_devices); 5802 goto out; 5803 } 5804 5805 if (!fs_devices->seeding) { 5806 __btrfs_close_devices(fs_devices); 5807 free_fs_devices(fs_devices); 5808 ret = -EINVAL; 5809 goto out; 5810 } 5811 5812 fs_devices->seed = root->fs_info->fs_devices->seed; 5813 root->fs_info->fs_devices->seed = fs_devices; 5814 out: 5815 return ret; 5816 } 5817 5818 static int read_one_dev(struct btrfs_root *root, 5819 struct extent_buffer *leaf, 5820 struct btrfs_dev_item *dev_item) 5821 { 5822 struct btrfs_device *device; 5823 u64 devid; 5824 int ret; 5825 u8 fs_uuid[BTRFS_UUID_SIZE]; 5826 u8 dev_uuid[BTRFS_UUID_SIZE]; 5827 5828 devid = btrfs_device_id(leaf, dev_item); 5829 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item), 5830 BTRFS_UUID_SIZE); 5831 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item), 5832 BTRFS_UUID_SIZE); 5833 5834 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) { 5835 ret = open_seed_devices(root, fs_uuid); 5836 if (ret && !btrfs_test_opt(root, DEGRADED)) 5837 return ret; 5838 } 5839 5840 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid); 5841 if (!device || !device->bdev) { 5842 if (!btrfs_test_opt(root, DEGRADED)) 5843 return -EIO; 5844 5845 if (!device) { 5846 btrfs_warn(root->fs_info, "devid %llu missing", devid); 5847 device = add_missing_dev(root, devid, dev_uuid); 5848 if (!device) 5849 return -ENOMEM; 5850 } else if (!device->missing) { 5851 /* 5852 * this happens when a device that was properly setup 5853 * in the device info lists suddenly goes bad. 5854 * device->bdev is NULL, and so we have to set 5855 * device->missing to one here 5856 */ 5857 root->fs_info->fs_devices->missing_devices++; 5858 device->missing = 1; 5859 } 5860 } 5861 5862 if (device->fs_devices != root->fs_info->fs_devices) { 5863 BUG_ON(device->writeable); 5864 if (device->generation != 5865 btrfs_device_generation(leaf, dev_item)) 5866 return -EINVAL; 5867 } 5868 5869 fill_device_from_item(leaf, dev_item, device); 5870 device->in_fs_metadata = 1; 5871 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 5872 device->fs_devices->total_rw_bytes += device->total_bytes; 5873 spin_lock(&root->fs_info->free_chunk_lock); 5874 root->fs_info->free_chunk_space += device->total_bytes - 5875 device->bytes_used; 5876 spin_unlock(&root->fs_info->free_chunk_lock); 5877 } 5878 ret = 0; 5879 return ret; 5880 } 5881 5882 int btrfs_read_sys_array(struct btrfs_root *root) 5883 { 5884 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 5885 struct extent_buffer *sb; 5886 struct btrfs_disk_key *disk_key; 5887 struct btrfs_chunk *chunk; 5888 u8 *ptr; 5889 unsigned long sb_ptr; 5890 int ret = 0; 5891 u32 num_stripes; 5892 u32 array_size; 5893 u32 len = 0; 5894 u32 cur; 5895 struct btrfs_key key; 5896 5897 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET, 5898 BTRFS_SUPER_INFO_SIZE); 5899 if (!sb) 5900 return -ENOMEM; 5901 btrfs_set_buffer_uptodate(sb); 5902 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); 5903 /* 5904 * The sb extent buffer is artifical and just used to read the system array. 5905 * btrfs_set_buffer_uptodate() call does not properly mark all it's 5906 * pages up-to-date when the page is larger: extent does not cover the 5907 * whole page and consequently check_page_uptodate does not find all 5908 * the page's extents up-to-date (the hole beyond sb), 5909 * write_extent_buffer then triggers a WARN_ON. 5910 * 5911 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle, 5912 * but sb spans only this function. Add an explicit SetPageUptodate call 5913 * to silence the warning eg. on PowerPC 64. 5914 */ 5915 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE) 5916 SetPageUptodate(sb->pages[0]); 5917 5918 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); 5919 array_size = btrfs_super_sys_array_size(super_copy); 5920 5921 ptr = super_copy->sys_chunk_array; 5922 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array); 5923 cur = 0; 5924 5925 while (cur < array_size) { 5926 disk_key = (struct btrfs_disk_key *)ptr; 5927 btrfs_disk_key_to_cpu(&key, disk_key); 5928 5929 len = sizeof(*disk_key); ptr += len; 5930 sb_ptr += len; 5931 cur += len; 5932 5933 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 5934 chunk = (struct btrfs_chunk *)sb_ptr; 5935 ret = read_one_chunk(root, &key, sb, chunk); 5936 if (ret) 5937 break; 5938 num_stripes = btrfs_chunk_num_stripes(sb, chunk); 5939 len = btrfs_chunk_item_size(num_stripes); 5940 } else { 5941 ret = -EIO; 5942 break; 5943 } 5944 ptr += len; 5945 sb_ptr += len; 5946 cur += len; 5947 } 5948 free_extent_buffer(sb); 5949 return ret; 5950 } 5951 5952 int btrfs_read_chunk_tree(struct btrfs_root *root) 5953 { 5954 struct btrfs_path *path; 5955 struct extent_buffer *leaf; 5956 struct btrfs_key key; 5957 struct btrfs_key found_key; 5958 int ret; 5959 int slot; 5960 5961 root = root->fs_info->chunk_root; 5962 5963 path = btrfs_alloc_path(); 5964 if (!path) 5965 return -ENOMEM; 5966 5967 mutex_lock(&uuid_mutex); 5968 lock_chunks(root); 5969 5970 /* 5971 * Read all device items, and then all the chunk items. All 5972 * device items are found before any chunk item (their object id 5973 * is smaller than the lowest possible object id for a chunk 5974 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID). 5975 */ 5976 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 5977 key.offset = 0; 5978 key.type = 0; 5979 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5980 if (ret < 0) 5981 goto error; 5982 while (1) { 5983 leaf = path->nodes[0]; 5984 slot = path->slots[0]; 5985 if (slot >= btrfs_header_nritems(leaf)) { 5986 ret = btrfs_next_leaf(root, path); 5987 if (ret == 0) 5988 continue; 5989 if (ret < 0) 5990 goto error; 5991 break; 5992 } 5993 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5994 if (found_key.type == BTRFS_DEV_ITEM_KEY) { 5995 struct btrfs_dev_item *dev_item; 5996 dev_item = btrfs_item_ptr(leaf, slot, 5997 struct btrfs_dev_item); 5998 ret = read_one_dev(root, leaf, dev_item); 5999 if (ret) 6000 goto error; 6001 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { 6002 struct btrfs_chunk *chunk; 6003 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 6004 ret = read_one_chunk(root, &found_key, leaf, chunk); 6005 if (ret) 6006 goto error; 6007 } 6008 path->slots[0]++; 6009 } 6010 ret = 0; 6011 error: 6012 unlock_chunks(root); 6013 mutex_unlock(&uuid_mutex); 6014 6015 btrfs_free_path(path); 6016 return ret; 6017 } 6018 6019 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info) 6020 { 6021 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 6022 struct btrfs_device *device; 6023 6024 mutex_lock(&fs_devices->device_list_mutex); 6025 list_for_each_entry(device, &fs_devices->devices, dev_list) 6026 device->dev_root = fs_info->dev_root; 6027 mutex_unlock(&fs_devices->device_list_mutex); 6028 } 6029 6030 static void __btrfs_reset_dev_stats(struct btrfs_device *dev) 6031 { 6032 int i; 6033 6034 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 6035 btrfs_dev_stat_reset(dev, i); 6036 } 6037 6038 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) 6039 { 6040 struct btrfs_key key; 6041 struct btrfs_key found_key; 6042 struct btrfs_root *dev_root = fs_info->dev_root; 6043 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 6044 struct extent_buffer *eb; 6045 int slot; 6046 int ret = 0; 6047 struct btrfs_device *device; 6048 struct btrfs_path *path = NULL; 6049 int i; 6050 6051 path = btrfs_alloc_path(); 6052 if (!path) { 6053 ret = -ENOMEM; 6054 goto out; 6055 } 6056 6057 mutex_lock(&fs_devices->device_list_mutex); 6058 list_for_each_entry(device, &fs_devices->devices, dev_list) { 6059 int item_size; 6060 struct btrfs_dev_stats_item *ptr; 6061 6062 key.objectid = 0; 6063 key.type = BTRFS_DEV_STATS_KEY; 6064 key.offset = device->devid; 6065 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 6066 if (ret) { 6067 __btrfs_reset_dev_stats(device); 6068 device->dev_stats_valid = 1; 6069 btrfs_release_path(path); 6070 continue; 6071 } 6072 slot = path->slots[0]; 6073 eb = path->nodes[0]; 6074 btrfs_item_key_to_cpu(eb, &found_key, slot); 6075 item_size = btrfs_item_size_nr(eb, slot); 6076 6077 ptr = btrfs_item_ptr(eb, slot, 6078 struct btrfs_dev_stats_item); 6079 6080 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 6081 if (item_size >= (1 + i) * sizeof(__le64)) 6082 btrfs_dev_stat_set(device, i, 6083 btrfs_dev_stats_value(eb, ptr, i)); 6084 else 6085 btrfs_dev_stat_reset(device, i); 6086 } 6087 6088 device->dev_stats_valid = 1; 6089 btrfs_dev_stat_print_on_load(device); 6090 btrfs_release_path(path); 6091 } 6092 mutex_unlock(&fs_devices->device_list_mutex); 6093 6094 out: 6095 btrfs_free_path(path); 6096 return ret < 0 ? ret : 0; 6097 } 6098 6099 static int update_dev_stat_item(struct btrfs_trans_handle *trans, 6100 struct btrfs_root *dev_root, 6101 struct btrfs_device *device) 6102 { 6103 struct btrfs_path *path; 6104 struct btrfs_key key; 6105 struct extent_buffer *eb; 6106 struct btrfs_dev_stats_item *ptr; 6107 int ret; 6108 int i; 6109 6110 key.objectid = 0; 6111 key.type = BTRFS_DEV_STATS_KEY; 6112 key.offset = device->devid; 6113 6114 path = btrfs_alloc_path(); 6115 BUG_ON(!path); 6116 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 6117 if (ret < 0) { 6118 printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n", 6119 ret, rcu_str_deref(device->name)); 6120 goto out; 6121 } 6122 6123 if (ret == 0 && 6124 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 6125 /* need to delete old one and insert a new one */ 6126 ret = btrfs_del_item(trans, dev_root, path); 6127 if (ret != 0) { 6128 printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n", 6129 rcu_str_deref(device->name), ret); 6130 goto out; 6131 } 6132 ret = 1; 6133 } 6134 6135 if (ret == 1) { 6136 /* need to insert a new item */ 6137 btrfs_release_path(path); 6138 ret = btrfs_insert_empty_item(trans, dev_root, path, 6139 &key, sizeof(*ptr)); 6140 if (ret < 0) { 6141 printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n", 6142 rcu_str_deref(device->name), ret); 6143 goto out; 6144 } 6145 } 6146 6147 eb = path->nodes[0]; 6148 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); 6149 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 6150 btrfs_set_dev_stats_value(eb, ptr, i, 6151 btrfs_dev_stat_read(device, i)); 6152 btrfs_mark_buffer_dirty(eb); 6153 6154 out: 6155 btrfs_free_path(path); 6156 return ret; 6157 } 6158 6159 /* 6160 * called from commit_transaction. Writes all changed device stats to disk. 6161 */ 6162 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, 6163 struct btrfs_fs_info *fs_info) 6164 { 6165 struct btrfs_root *dev_root = fs_info->dev_root; 6166 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 6167 struct btrfs_device *device; 6168 int ret = 0; 6169 6170 mutex_lock(&fs_devices->device_list_mutex); 6171 list_for_each_entry(device, &fs_devices->devices, dev_list) { 6172 if (!device->dev_stats_valid || !device->dev_stats_dirty) 6173 continue; 6174 6175 ret = update_dev_stat_item(trans, dev_root, device); 6176 if (!ret) 6177 device->dev_stats_dirty = 0; 6178 } 6179 mutex_unlock(&fs_devices->device_list_mutex); 6180 6181 return ret; 6182 } 6183 6184 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) 6185 { 6186 btrfs_dev_stat_inc(dev, index); 6187 btrfs_dev_stat_print_on_error(dev); 6188 } 6189 6190 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev) 6191 { 6192 if (!dev->dev_stats_valid) 6193 return; 6194 printk_ratelimited_in_rcu(KERN_ERR 6195 "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 6196 rcu_str_deref(dev->name), 6197 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 6198 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 6199 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 6200 btrfs_dev_stat_read(dev, 6201 BTRFS_DEV_STAT_CORRUPTION_ERRS), 6202 btrfs_dev_stat_read(dev, 6203 BTRFS_DEV_STAT_GENERATION_ERRS)); 6204 } 6205 6206 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) 6207 { 6208 int i; 6209 6210 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 6211 if (btrfs_dev_stat_read(dev, i) != 0) 6212 break; 6213 if (i == BTRFS_DEV_STAT_VALUES_MAX) 6214 return; /* all values == 0, suppress message */ 6215 6216 printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 6217 rcu_str_deref(dev->name), 6218 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 6219 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 6220 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 6221 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), 6222 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); 6223 } 6224 6225 int btrfs_get_dev_stats(struct btrfs_root *root, 6226 struct btrfs_ioctl_get_dev_stats *stats) 6227 { 6228 struct btrfs_device *dev; 6229 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 6230 int i; 6231 6232 mutex_lock(&fs_devices->device_list_mutex); 6233 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL); 6234 mutex_unlock(&fs_devices->device_list_mutex); 6235 6236 if (!dev) { 6237 printk(KERN_WARNING 6238 "btrfs: get dev_stats failed, device not found\n"); 6239 return -ENODEV; 6240 } else if (!dev->dev_stats_valid) { 6241 printk(KERN_WARNING 6242 "btrfs: get dev_stats failed, not yet valid\n"); 6243 return -ENODEV; 6244 } else if (stats->flags & BTRFS_DEV_STATS_RESET) { 6245 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 6246 if (stats->nr_items > i) 6247 stats->values[i] = 6248 btrfs_dev_stat_read_and_reset(dev, i); 6249 else 6250 btrfs_dev_stat_reset(dev, i); 6251 } 6252 } else { 6253 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 6254 if (stats->nr_items > i) 6255 stats->values[i] = btrfs_dev_stat_read(dev, i); 6256 } 6257 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) 6258 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; 6259 return 0; 6260 } 6261 6262 int btrfs_scratch_superblock(struct btrfs_device *device) 6263 { 6264 struct buffer_head *bh; 6265 struct btrfs_super_block *disk_super; 6266 6267 bh = btrfs_read_dev_super(device->bdev); 6268 if (!bh) 6269 return -EINVAL; 6270 disk_super = (struct btrfs_super_block *)bh->b_data; 6271 6272 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 6273 set_buffer_dirty(bh); 6274 sync_dirty_buffer(bh); 6275 brelse(bh); 6276 6277 return 0; 6278 } 6279