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 "compat.h" 29 #include "ctree.h" 30 #include "extent_map.h" 31 #include "disk-io.h" 32 #include "transaction.h" 33 #include "print-tree.h" 34 #include "volumes.h" 35 #include "async-thread.h" 36 #include "check-integrity.h" 37 #include "rcu-string.h" 38 #include "math.h" 39 #include "dev-replace.h" 40 41 static int init_first_rw_device(struct btrfs_trans_handle *trans, 42 struct btrfs_root *root, 43 struct btrfs_device *device); 44 static int btrfs_relocate_sys_chunks(struct btrfs_root *root); 45 static void __btrfs_reset_dev_stats(struct btrfs_device *dev); 46 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); 47 48 static DEFINE_MUTEX(uuid_mutex); 49 static LIST_HEAD(fs_uuids); 50 51 static void lock_chunks(struct btrfs_root *root) 52 { 53 mutex_lock(&root->fs_info->chunk_mutex); 54 } 55 56 static void unlock_chunks(struct btrfs_root *root) 57 { 58 mutex_unlock(&root->fs_info->chunk_mutex); 59 } 60 61 static void free_fs_devices(struct btrfs_fs_devices *fs_devices) 62 { 63 struct btrfs_device *device; 64 WARN_ON(fs_devices->opened); 65 while (!list_empty(&fs_devices->devices)) { 66 device = list_entry(fs_devices->devices.next, 67 struct btrfs_device, dev_list); 68 list_del(&device->dev_list); 69 rcu_string_free(device->name); 70 kfree(device); 71 } 72 kfree(fs_devices); 73 } 74 75 static void btrfs_kobject_uevent(struct block_device *bdev, 76 enum kobject_action action) 77 { 78 int ret; 79 80 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 81 if (ret) 82 pr_warn("Sending event '%d' to kobject: '%s' (%p): failed\n", 83 action, 84 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 85 &disk_to_dev(bdev->bd_disk)->kobj); 86 } 87 88 void btrfs_cleanup_fs_uuids(void) 89 { 90 struct btrfs_fs_devices *fs_devices; 91 92 while (!list_empty(&fs_uuids)) { 93 fs_devices = list_entry(fs_uuids.next, 94 struct btrfs_fs_devices, list); 95 list_del(&fs_devices->list); 96 free_fs_devices(fs_devices); 97 } 98 } 99 100 static noinline struct btrfs_device *__find_device(struct list_head *head, 101 u64 devid, u8 *uuid) 102 { 103 struct btrfs_device *dev; 104 105 list_for_each_entry(dev, head, dev_list) { 106 if (dev->devid == devid && 107 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { 108 return dev; 109 } 110 } 111 return NULL; 112 } 113 114 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid) 115 { 116 struct btrfs_fs_devices *fs_devices; 117 118 list_for_each_entry(fs_devices, &fs_uuids, list) { 119 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) 120 return fs_devices; 121 } 122 return NULL; 123 } 124 125 static int 126 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder, 127 int flush, struct block_device **bdev, 128 struct buffer_head **bh) 129 { 130 int ret; 131 132 *bdev = blkdev_get_by_path(device_path, flags, holder); 133 134 if (IS_ERR(*bdev)) { 135 ret = PTR_ERR(*bdev); 136 printk(KERN_INFO "btrfs: open %s failed\n", device_path); 137 goto error; 138 } 139 140 if (flush) 141 filemap_write_and_wait((*bdev)->bd_inode->i_mapping); 142 ret = set_blocksize(*bdev, 4096); 143 if (ret) { 144 blkdev_put(*bdev, flags); 145 goto error; 146 } 147 invalidate_bdev(*bdev); 148 *bh = btrfs_read_dev_super(*bdev); 149 if (!*bh) { 150 ret = -EINVAL; 151 blkdev_put(*bdev, flags); 152 goto error; 153 } 154 155 return 0; 156 157 error: 158 *bdev = NULL; 159 *bh = NULL; 160 return ret; 161 } 162 163 static void requeue_list(struct btrfs_pending_bios *pending_bios, 164 struct bio *head, struct bio *tail) 165 { 166 167 struct bio *old_head; 168 169 old_head = pending_bios->head; 170 pending_bios->head = head; 171 if (pending_bios->tail) 172 tail->bi_next = old_head; 173 else 174 pending_bios->tail = tail; 175 } 176 177 /* 178 * we try to collect pending bios for a device so we don't get a large 179 * number of procs sending bios down to the same device. This greatly 180 * improves the schedulers ability to collect and merge the bios. 181 * 182 * But, it also turns into a long list of bios to process and that is sure 183 * to eventually make the worker thread block. The solution here is to 184 * make some progress and then put this work struct back at the end of 185 * the list if the block device is congested. This way, multiple devices 186 * can make progress from a single worker thread. 187 */ 188 static noinline void run_scheduled_bios(struct btrfs_device *device) 189 { 190 struct bio *pending; 191 struct backing_dev_info *bdi; 192 struct btrfs_fs_info *fs_info; 193 struct btrfs_pending_bios *pending_bios; 194 struct bio *tail; 195 struct bio *cur; 196 int again = 0; 197 unsigned long num_run; 198 unsigned long batch_run = 0; 199 unsigned long limit; 200 unsigned long last_waited = 0; 201 int force_reg = 0; 202 int sync_pending = 0; 203 struct blk_plug plug; 204 205 /* 206 * this function runs all the bios we've collected for 207 * a particular device. We don't want to wander off to 208 * another device without first sending all of these down. 209 * So, setup a plug here and finish it off before we return 210 */ 211 blk_start_plug(&plug); 212 213 bdi = blk_get_backing_dev_info(device->bdev); 214 fs_info = device->dev_root->fs_info; 215 limit = btrfs_async_submit_limit(fs_info); 216 limit = limit * 2 / 3; 217 218 loop: 219 spin_lock(&device->io_lock); 220 221 loop_lock: 222 num_run = 0; 223 224 /* take all the bios off the list at once and process them 225 * later on (without the lock held). But, remember the 226 * tail and other pointers so the bios can be properly reinserted 227 * into the list if we hit congestion 228 */ 229 if (!force_reg && device->pending_sync_bios.head) { 230 pending_bios = &device->pending_sync_bios; 231 force_reg = 1; 232 } else { 233 pending_bios = &device->pending_bios; 234 force_reg = 0; 235 } 236 237 pending = pending_bios->head; 238 tail = pending_bios->tail; 239 WARN_ON(pending && !tail); 240 241 /* 242 * if pending was null this time around, no bios need processing 243 * at all and we can stop. Otherwise it'll loop back up again 244 * and do an additional check so no bios are missed. 245 * 246 * device->running_pending is used to synchronize with the 247 * schedule_bio code. 248 */ 249 if (device->pending_sync_bios.head == NULL && 250 device->pending_bios.head == NULL) { 251 again = 0; 252 device->running_pending = 0; 253 } else { 254 again = 1; 255 device->running_pending = 1; 256 } 257 258 pending_bios->head = NULL; 259 pending_bios->tail = NULL; 260 261 spin_unlock(&device->io_lock); 262 263 while (pending) { 264 265 rmb(); 266 /* we want to work on both lists, but do more bios on the 267 * sync list than the regular list 268 */ 269 if ((num_run > 32 && 270 pending_bios != &device->pending_sync_bios && 271 device->pending_sync_bios.head) || 272 (num_run > 64 && pending_bios == &device->pending_sync_bios && 273 device->pending_bios.head)) { 274 spin_lock(&device->io_lock); 275 requeue_list(pending_bios, pending, tail); 276 goto loop_lock; 277 } 278 279 cur = pending; 280 pending = pending->bi_next; 281 cur->bi_next = NULL; 282 283 if (atomic_dec_return(&fs_info->nr_async_bios) < limit && 284 waitqueue_active(&fs_info->async_submit_wait)) 285 wake_up(&fs_info->async_submit_wait); 286 287 BUG_ON(atomic_read(&cur->bi_cnt) == 0); 288 289 /* 290 * if we're doing the sync list, record that our 291 * plug has some sync requests on it 292 * 293 * If we're doing the regular list and there are 294 * sync requests sitting around, unplug before 295 * we add more 296 */ 297 if (pending_bios == &device->pending_sync_bios) { 298 sync_pending = 1; 299 } else if (sync_pending) { 300 blk_finish_plug(&plug); 301 blk_start_plug(&plug); 302 sync_pending = 0; 303 } 304 305 btrfsic_submit_bio(cur->bi_rw, cur); 306 num_run++; 307 batch_run++; 308 if (need_resched()) 309 cond_resched(); 310 311 /* 312 * we made progress, there is more work to do and the bdi 313 * is now congested. Back off and let other work structs 314 * run instead 315 */ 316 if (pending && bdi_write_congested(bdi) && batch_run > 8 && 317 fs_info->fs_devices->open_devices > 1) { 318 struct io_context *ioc; 319 320 ioc = current->io_context; 321 322 /* 323 * the main goal here is that we don't want to 324 * block if we're going to be able to submit 325 * more requests without blocking. 326 * 327 * This code does two great things, it pokes into 328 * the elevator code from a filesystem _and_ 329 * it makes assumptions about how batching works. 330 */ 331 if (ioc && ioc->nr_batch_requests > 0 && 332 time_before(jiffies, ioc->last_waited + HZ/50UL) && 333 (last_waited == 0 || 334 ioc->last_waited == last_waited)) { 335 /* 336 * we want to go through our batch of 337 * requests and stop. So, we copy out 338 * the ioc->last_waited time and test 339 * against it before looping 340 */ 341 last_waited = ioc->last_waited; 342 if (need_resched()) 343 cond_resched(); 344 continue; 345 } 346 spin_lock(&device->io_lock); 347 requeue_list(pending_bios, pending, tail); 348 device->running_pending = 1; 349 350 spin_unlock(&device->io_lock); 351 btrfs_requeue_work(&device->work); 352 goto done; 353 } 354 /* unplug every 64 requests just for good measure */ 355 if (batch_run % 64 == 0) { 356 blk_finish_plug(&plug); 357 blk_start_plug(&plug); 358 sync_pending = 0; 359 } 360 } 361 362 cond_resched(); 363 if (again) 364 goto loop; 365 366 spin_lock(&device->io_lock); 367 if (device->pending_bios.head || device->pending_sync_bios.head) 368 goto loop_lock; 369 spin_unlock(&device->io_lock); 370 371 done: 372 blk_finish_plug(&plug); 373 } 374 375 static void pending_bios_fn(struct btrfs_work *work) 376 { 377 struct btrfs_device *device; 378 379 device = container_of(work, struct btrfs_device, work); 380 run_scheduled_bios(device); 381 } 382 383 static noinline int device_list_add(const char *path, 384 struct btrfs_super_block *disk_super, 385 u64 devid, struct btrfs_fs_devices **fs_devices_ret) 386 { 387 struct btrfs_device *device; 388 struct btrfs_fs_devices *fs_devices; 389 struct rcu_string *name; 390 u64 found_transid = btrfs_super_generation(disk_super); 391 392 fs_devices = find_fsid(disk_super->fsid); 393 if (!fs_devices) { 394 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 395 if (!fs_devices) 396 return -ENOMEM; 397 INIT_LIST_HEAD(&fs_devices->devices); 398 INIT_LIST_HEAD(&fs_devices->alloc_list); 399 list_add(&fs_devices->list, &fs_uuids); 400 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE); 401 fs_devices->latest_devid = devid; 402 fs_devices->latest_trans = found_transid; 403 mutex_init(&fs_devices->device_list_mutex); 404 device = NULL; 405 } else { 406 device = __find_device(&fs_devices->devices, devid, 407 disk_super->dev_item.uuid); 408 } 409 if (!device) { 410 if (fs_devices->opened) 411 return -EBUSY; 412 413 device = kzalloc(sizeof(*device), GFP_NOFS); 414 if (!device) { 415 /* we can safely leave the fs_devices entry around */ 416 return -ENOMEM; 417 } 418 device->devid = devid; 419 device->dev_stats_valid = 0; 420 device->work.func = pending_bios_fn; 421 memcpy(device->uuid, disk_super->dev_item.uuid, 422 BTRFS_UUID_SIZE); 423 spin_lock_init(&device->io_lock); 424 425 name = rcu_string_strdup(path, GFP_NOFS); 426 if (!name) { 427 kfree(device); 428 return -ENOMEM; 429 } 430 rcu_assign_pointer(device->name, name); 431 INIT_LIST_HEAD(&device->dev_alloc_list); 432 433 /* init readahead state */ 434 spin_lock_init(&device->reada_lock); 435 device->reada_curr_zone = NULL; 436 atomic_set(&device->reada_in_flight, 0); 437 device->reada_next = 0; 438 INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT); 439 INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT); 440 441 mutex_lock(&fs_devices->device_list_mutex); 442 list_add_rcu(&device->dev_list, &fs_devices->devices); 443 mutex_unlock(&fs_devices->device_list_mutex); 444 445 device->fs_devices = fs_devices; 446 fs_devices->num_devices++; 447 } else if (!device->name || strcmp(device->name->str, path)) { 448 name = rcu_string_strdup(path, GFP_NOFS); 449 if (!name) 450 return -ENOMEM; 451 rcu_string_free(device->name); 452 rcu_assign_pointer(device->name, name); 453 if (device->missing) { 454 fs_devices->missing_devices--; 455 device->missing = 0; 456 } 457 } 458 459 if (found_transid > fs_devices->latest_trans) { 460 fs_devices->latest_devid = devid; 461 fs_devices->latest_trans = found_transid; 462 } 463 *fs_devices_ret = fs_devices; 464 return 0; 465 } 466 467 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) 468 { 469 struct btrfs_fs_devices *fs_devices; 470 struct btrfs_device *device; 471 struct btrfs_device *orig_dev; 472 473 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 474 if (!fs_devices) 475 return ERR_PTR(-ENOMEM); 476 477 INIT_LIST_HEAD(&fs_devices->devices); 478 INIT_LIST_HEAD(&fs_devices->alloc_list); 479 INIT_LIST_HEAD(&fs_devices->list); 480 mutex_init(&fs_devices->device_list_mutex); 481 fs_devices->latest_devid = orig->latest_devid; 482 fs_devices->latest_trans = orig->latest_trans; 483 fs_devices->total_devices = orig->total_devices; 484 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid)); 485 486 /* We have held the volume lock, it is safe to get the devices. */ 487 list_for_each_entry(orig_dev, &orig->devices, dev_list) { 488 struct rcu_string *name; 489 490 device = kzalloc(sizeof(*device), GFP_NOFS); 491 if (!device) 492 goto error; 493 494 /* 495 * This is ok to do without rcu read locked because we hold the 496 * uuid mutex so nothing we touch in here is going to disappear. 497 */ 498 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS); 499 if (!name) { 500 kfree(device); 501 goto error; 502 } 503 rcu_assign_pointer(device->name, name); 504 505 device->devid = orig_dev->devid; 506 device->work.func = pending_bios_fn; 507 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid)); 508 spin_lock_init(&device->io_lock); 509 INIT_LIST_HEAD(&device->dev_list); 510 INIT_LIST_HEAD(&device->dev_alloc_list); 511 512 list_add(&device->dev_list, &fs_devices->devices); 513 device->fs_devices = fs_devices; 514 fs_devices->num_devices++; 515 } 516 return fs_devices; 517 error: 518 free_fs_devices(fs_devices); 519 return ERR_PTR(-ENOMEM); 520 } 521 522 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info, 523 struct btrfs_fs_devices *fs_devices, int step) 524 { 525 struct btrfs_device *device, *next; 526 527 struct block_device *latest_bdev = NULL; 528 u64 latest_devid = 0; 529 u64 latest_transid = 0; 530 531 mutex_lock(&uuid_mutex); 532 again: 533 /* This is the initialized path, it is safe to release the devices. */ 534 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 535 if (device->in_fs_metadata) { 536 if (!device->is_tgtdev_for_dev_replace && 537 (!latest_transid || 538 device->generation > latest_transid)) { 539 latest_devid = device->devid; 540 latest_transid = device->generation; 541 latest_bdev = device->bdev; 542 } 543 continue; 544 } 545 546 if (device->devid == BTRFS_DEV_REPLACE_DEVID) { 547 /* 548 * In the first step, keep the device which has 549 * the correct fsid and the devid that is used 550 * for the dev_replace procedure. 551 * In the second step, the dev_replace state is 552 * read from the device tree and it is known 553 * whether the procedure is really active or 554 * not, which means whether this device is 555 * used or whether it should be removed. 556 */ 557 if (step == 0 || device->is_tgtdev_for_dev_replace) { 558 continue; 559 } 560 } 561 if (device->bdev) { 562 blkdev_put(device->bdev, device->mode); 563 device->bdev = NULL; 564 fs_devices->open_devices--; 565 } 566 if (device->writeable) { 567 list_del_init(&device->dev_alloc_list); 568 device->writeable = 0; 569 if (!device->is_tgtdev_for_dev_replace) 570 fs_devices->rw_devices--; 571 } 572 list_del_init(&device->dev_list); 573 fs_devices->num_devices--; 574 rcu_string_free(device->name); 575 kfree(device); 576 } 577 578 if (fs_devices->seed) { 579 fs_devices = fs_devices->seed; 580 goto again; 581 } 582 583 fs_devices->latest_bdev = latest_bdev; 584 fs_devices->latest_devid = latest_devid; 585 fs_devices->latest_trans = latest_transid; 586 587 mutex_unlock(&uuid_mutex); 588 } 589 590 static void __free_device(struct work_struct *work) 591 { 592 struct btrfs_device *device; 593 594 device = container_of(work, struct btrfs_device, rcu_work); 595 596 if (device->bdev) 597 blkdev_put(device->bdev, device->mode); 598 599 rcu_string_free(device->name); 600 kfree(device); 601 } 602 603 static void free_device(struct rcu_head *head) 604 { 605 struct btrfs_device *device; 606 607 device = container_of(head, struct btrfs_device, rcu); 608 609 INIT_WORK(&device->rcu_work, __free_device); 610 schedule_work(&device->rcu_work); 611 } 612 613 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 614 { 615 struct btrfs_device *device; 616 617 if (--fs_devices->opened > 0) 618 return 0; 619 620 mutex_lock(&fs_devices->device_list_mutex); 621 list_for_each_entry(device, &fs_devices->devices, dev_list) { 622 struct btrfs_device *new_device; 623 struct rcu_string *name; 624 625 if (device->bdev) 626 fs_devices->open_devices--; 627 628 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 629 list_del_init(&device->dev_alloc_list); 630 fs_devices->rw_devices--; 631 } 632 633 if (device->can_discard) 634 fs_devices->num_can_discard--; 635 636 new_device = kmalloc(sizeof(*new_device), GFP_NOFS); 637 BUG_ON(!new_device); /* -ENOMEM */ 638 memcpy(new_device, device, sizeof(*new_device)); 639 640 /* Safe because we are under uuid_mutex */ 641 if (device->name) { 642 name = rcu_string_strdup(device->name->str, GFP_NOFS); 643 BUG_ON(device->name && !name); /* -ENOMEM */ 644 rcu_assign_pointer(new_device->name, name); 645 } 646 new_device->bdev = NULL; 647 new_device->writeable = 0; 648 new_device->in_fs_metadata = 0; 649 new_device->can_discard = 0; 650 list_replace_rcu(&device->dev_list, &new_device->dev_list); 651 652 call_rcu(&device->rcu, free_device); 653 } 654 mutex_unlock(&fs_devices->device_list_mutex); 655 656 WARN_ON(fs_devices->open_devices); 657 WARN_ON(fs_devices->rw_devices); 658 fs_devices->opened = 0; 659 fs_devices->seeding = 0; 660 661 return 0; 662 } 663 664 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 665 { 666 struct btrfs_fs_devices *seed_devices = NULL; 667 int ret; 668 669 mutex_lock(&uuid_mutex); 670 ret = __btrfs_close_devices(fs_devices); 671 if (!fs_devices->opened) { 672 seed_devices = fs_devices->seed; 673 fs_devices->seed = NULL; 674 } 675 mutex_unlock(&uuid_mutex); 676 677 while (seed_devices) { 678 fs_devices = seed_devices; 679 seed_devices = fs_devices->seed; 680 __btrfs_close_devices(fs_devices); 681 free_fs_devices(fs_devices); 682 } 683 return ret; 684 } 685 686 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 687 fmode_t flags, void *holder) 688 { 689 struct request_queue *q; 690 struct block_device *bdev; 691 struct list_head *head = &fs_devices->devices; 692 struct btrfs_device *device; 693 struct block_device *latest_bdev = NULL; 694 struct buffer_head *bh; 695 struct btrfs_super_block *disk_super; 696 u64 latest_devid = 0; 697 u64 latest_transid = 0; 698 u64 devid; 699 int seeding = 1; 700 int ret = 0; 701 702 flags |= FMODE_EXCL; 703 704 list_for_each_entry(device, head, dev_list) { 705 if (device->bdev) 706 continue; 707 if (!device->name) 708 continue; 709 710 ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, 711 &bdev, &bh); 712 if (ret) 713 continue; 714 715 disk_super = (struct btrfs_super_block *)bh->b_data; 716 devid = btrfs_stack_device_id(&disk_super->dev_item); 717 if (devid != device->devid) 718 goto error_brelse; 719 720 if (memcmp(device->uuid, disk_super->dev_item.uuid, 721 BTRFS_UUID_SIZE)) 722 goto error_brelse; 723 724 device->generation = btrfs_super_generation(disk_super); 725 if (!latest_transid || device->generation > latest_transid) { 726 latest_devid = devid; 727 latest_transid = device->generation; 728 latest_bdev = bdev; 729 } 730 731 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { 732 device->writeable = 0; 733 } else { 734 device->writeable = !bdev_read_only(bdev); 735 seeding = 0; 736 } 737 738 q = bdev_get_queue(bdev); 739 if (blk_queue_discard(q)) { 740 device->can_discard = 1; 741 fs_devices->num_can_discard++; 742 } 743 744 device->bdev = bdev; 745 device->in_fs_metadata = 0; 746 device->mode = flags; 747 748 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 749 fs_devices->rotating = 1; 750 751 fs_devices->open_devices++; 752 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 753 fs_devices->rw_devices++; 754 list_add(&device->dev_alloc_list, 755 &fs_devices->alloc_list); 756 } 757 brelse(bh); 758 continue; 759 760 error_brelse: 761 brelse(bh); 762 blkdev_put(bdev, flags); 763 continue; 764 } 765 if (fs_devices->open_devices == 0) { 766 ret = -EINVAL; 767 goto out; 768 } 769 fs_devices->seeding = seeding; 770 fs_devices->opened = 1; 771 fs_devices->latest_bdev = latest_bdev; 772 fs_devices->latest_devid = latest_devid; 773 fs_devices->latest_trans = latest_transid; 774 fs_devices->total_rw_bytes = 0; 775 out: 776 return ret; 777 } 778 779 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 780 fmode_t flags, void *holder) 781 { 782 int ret; 783 784 mutex_lock(&uuid_mutex); 785 if (fs_devices->opened) { 786 fs_devices->opened++; 787 ret = 0; 788 } else { 789 ret = __btrfs_open_devices(fs_devices, flags, holder); 790 } 791 mutex_unlock(&uuid_mutex); 792 return ret; 793 } 794 795 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, 796 struct btrfs_fs_devices **fs_devices_ret) 797 { 798 struct btrfs_super_block *disk_super; 799 struct block_device *bdev; 800 struct buffer_head *bh; 801 int ret; 802 u64 devid; 803 u64 transid; 804 u64 total_devices; 805 806 flags |= FMODE_EXCL; 807 mutex_lock(&uuid_mutex); 808 ret = btrfs_get_bdev_and_sb(path, flags, holder, 0, &bdev, &bh); 809 if (ret) 810 goto error; 811 disk_super = (struct btrfs_super_block *)bh->b_data; 812 devid = btrfs_stack_device_id(&disk_super->dev_item); 813 transid = btrfs_super_generation(disk_super); 814 total_devices = btrfs_super_num_devices(disk_super); 815 if (disk_super->label[0]) { 816 if (disk_super->label[BTRFS_LABEL_SIZE - 1]) 817 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0'; 818 printk(KERN_INFO "device label %s ", disk_super->label); 819 } else { 820 printk(KERN_INFO "device fsid %pU ", disk_super->fsid); 821 } 822 printk(KERN_CONT "devid %llu transid %llu %s\n", 823 (unsigned long long)devid, (unsigned long long)transid, path); 824 ret = device_list_add(path, disk_super, devid, fs_devices_ret); 825 if (!ret && fs_devices_ret) 826 (*fs_devices_ret)->total_devices = total_devices; 827 brelse(bh); 828 blkdev_put(bdev, flags); 829 error: 830 mutex_unlock(&uuid_mutex); 831 return ret; 832 } 833 834 /* helper to account the used device space in the range */ 835 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, 836 u64 end, u64 *length) 837 { 838 struct btrfs_key key; 839 struct btrfs_root *root = device->dev_root; 840 struct btrfs_dev_extent *dev_extent; 841 struct btrfs_path *path; 842 u64 extent_end; 843 int ret; 844 int slot; 845 struct extent_buffer *l; 846 847 *length = 0; 848 849 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace) 850 return 0; 851 852 path = btrfs_alloc_path(); 853 if (!path) 854 return -ENOMEM; 855 path->reada = 2; 856 857 key.objectid = device->devid; 858 key.offset = start; 859 key.type = BTRFS_DEV_EXTENT_KEY; 860 861 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 862 if (ret < 0) 863 goto out; 864 if (ret > 0) { 865 ret = btrfs_previous_item(root, path, key.objectid, key.type); 866 if (ret < 0) 867 goto out; 868 } 869 870 while (1) { 871 l = path->nodes[0]; 872 slot = path->slots[0]; 873 if (slot >= btrfs_header_nritems(l)) { 874 ret = btrfs_next_leaf(root, path); 875 if (ret == 0) 876 continue; 877 if (ret < 0) 878 goto out; 879 880 break; 881 } 882 btrfs_item_key_to_cpu(l, &key, slot); 883 884 if (key.objectid < device->devid) 885 goto next; 886 887 if (key.objectid > device->devid) 888 break; 889 890 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 891 goto next; 892 893 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 894 extent_end = key.offset + btrfs_dev_extent_length(l, 895 dev_extent); 896 if (key.offset <= start && extent_end > end) { 897 *length = end - start + 1; 898 break; 899 } else if (key.offset <= start && extent_end > start) 900 *length += extent_end - start; 901 else if (key.offset > start && extent_end <= end) 902 *length += extent_end - key.offset; 903 else if (key.offset > start && key.offset <= end) { 904 *length += end - key.offset + 1; 905 break; 906 } else if (key.offset > end) 907 break; 908 909 next: 910 path->slots[0]++; 911 } 912 ret = 0; 913 out: 914 btrfs_free_path(path); 915 return ret; 916 } 917 918 /* 919 * find_free_dev_extent - find free space in the specified device 920 * @device: the device which we search the free space in 921 * @num_bytes: the size of the free space that we need 922 * @start: store the start of the free space. 923 * @len: the size of the free space. that we find, or the size of the max 924 * free space if we don't find suitable free space 925 * 926 * this uses a pretty simple search, the expectation is that it is 927 * called very infrequently and that a given device has a small number 928 * of extents 929 * 930 * @start is used to store the start of the free space if we find. But if we 931 * don't find suitable free space, it will be used to store the start position 932 * of the max free space. 933 * 934 * @len is used to store the size of the free space that we find. 935 * But if we don't find suitable free space, it is used to store the size of 936 * the max free space. 937 */ 938 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes, 939 u64 *start, u64 *len) 940 { 941 struct btrfs_key key; 942 struct btrfs_root *root = device->dev_root; 943 struct btrfs_dev_extent *dev_extent; 944 struct btrfs_path *path; 945 u64 hole_size; 946 u64 max_hole_start; 947 u64 max_hole_size; 948 u64 extent_end; 949 u64 search_start; 950 u64 search_end = device->total_bytes; 951 int ret; 952 int slot; 953 struct extent_buffer *l; 954 955 /* FIXME use last free of some kind */ 956 957 /* we don't want to overwrite the superblock on the drive, 958 * so we make sure to start at an offset of at least 1MB 959 */ 960 search_start = max(root->fs_info->alloc_start, 1024ull * 1024); 961 962 max_hole_start = search_start; 963 max_hole_size = 0; 964 hole_size = 0; 965 966 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) { 967 ret = -ENOSPC; 968 goto error; 969 } 970 971 path = btrfs_alloc_path(); 972 if (!path) { 973 ret = -ENOMEM; 974 goto error; 975 } 976 path->reada = 2; 977 978 key.objectid = device->devid; 979 key.offset = search_start; 980 key.type = BTRFS_DEV_EXTENT_KEY; 981 982 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 983 if (ret < 0) 984 goto out; 985 if (ret > 0) { 986 ret = btrfs_previous_item(root, path, key.objectid, key.type); 987 if (ret < 0) 988 goto out; 989 } 990 991 while (1) { 992 l = path->nodes[0]; 993 slot = path->slots[0]; 994 if (slot >= btrfs_header_nritems(l)) { 995 ret = btrfs_next_leaf(root, path); 996 if (ret == 0) 997 continue; 998 if (ret < 0) 999 goto out; 1000 1001 break; 1002 } 1003 btrfs_item_key_to_cpu(l, &key, slot); 1004 1005 if (key.objectid < device->devid) 1006 goto next; 1007 1008 if (key.objectid > device->devid) 1009 break; 1010 1011 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 1012 goto next; 1013 1014 if (key.offset > search_start) { 1015 hole_size = key.offset - search_start; 1016 1017 if (hole_size > max_hole_size) { 1018 max_hole_start = search_start; 1019 max_hole_size = hole_size; 1020 } 1021 1022 /* 1023 * If this free space is greater than which we need, 1024 * it must be the max free space that we have found 1025 * until now, so max_hole_start must point to the start 1026 * of this free space and the length of this free space 1027 * is stored in max_hole_size. Thus, we return 1028 * max_hole_start and max_hole_size and go back to the 1029 * caller. 1030 */ 1031 if (hole_size >= num_bytes) { 1032 ret = 0; 1033 goto out; 1034 } 1035 } 1036 1037 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 1038 extent_end = key.offset + btrfs_dev_extent_length(l, 1039 dev_extent); 1040 if (extent_end > search_start) 1041 search_start = extent_end; 1042 next: 1043 path->slots[0]++; 1044 cond_resched(); 1045 } 1046 1047 /* 1048 * At this point, search_start should be the end of 1049 * allocated dev extents, and when shrinking the device, 1050 * search_end may be smaller than search_start. 1051 */ 1052 if (search_end > search_start) 1053 hole_size = search_end - search_start; 1054 1055 if (hole_size > max_hole_size) { 1056 max_hole_start = search_start; 1057 max_hole_size = hole_size; 1058 } 1059 1060 /* See above. */ 1061 if (hole_size < num_bytes) 1062 ret = -ENOSPC; 1063 else 1064 ret = 0; 1065 1066 out: 1067 btrfs_free_path(path); 1068 error: 1069 *start = max_hole_start; 1070 if (len) 1071 *len = max_hole_size; 1072 return ret; 1073 } 1074 1075 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, 1076 struct btrfs_device *device, 1077 u64 start) 1078 { 1079 int ret; 1080 struct btrfs_path *path; 1081 struct btrfs_root *root = device->dev_root; 1082 struct btrfs_key key; 1083 struct btrfs_key found_key; 1084 struct extent_buffer *leaf = NULL; 1085 struct btrfs_dev_extent *extent = NULL; 1086 1087 path = btrfs_alloc_path(); 1088 if (!path) 1089 return -ENOMEM; 1090 1091 key.objectid = device->devid; 1092 key.offset = start; 1093 key.type = BTRFS_DEV_EXTENT_KEY; 1094 again: 1095 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1096 if (ret > 0) { 1097 ret = btrfs_previous_item(root, path, key.objectid, 1098 BTRFS_DEV_EXTENT_KEY); 1099 if (ret) 1100 goto out; 1101 leaf = path->nodes[0]; 1102 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1103 extent = btrfs_item_ptr(leaf, path->slots[0], 1104 struct btrfs_dev_extent); 1105 BUG_ON(found_key.offset > start || found_key.offset + 1106 btrfs_dev_extent_length(leaf, extent) < start); 1107 key = found_key; 1108 btrfs_release_path(path); 1109 goto again; 1110 } else if (ret == 0) { 1111 leaf = path->nodes[0]; 1112 extent = btrfs_item_ptr(leaf, path->slots[0], 1113 struct btrfs_dev_extent); 1114 } else { 1115 btrfs_error(root->fs_info, ret, "Slot search failed"); 1116 goto out; 1117 } 1118 1119 if (device->bytes_used > 0) { 1120 u64 len = btrfs_dev_extent_length(leaf, extent); 1121 device->bytes_used -= len; 1122 spin_lock(&root->fs_info->free_chunk_lock); 1123 root->fs_info->free_chunk_space += len; 1124 spin_unlock(&root->fs_info->free_chunk_lock); 1125 } 1126 ret = btrfs_del_item(trans, root, path); 1127 if (ret) { 1128 btrfs_error(root->fs_info, ret, 1129 "Failed to remove dev extent item"); 1130 } 1131 out: 1132 btrfs_free_path(path); 1133 return ret; 1134 } 1135 1136 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, 1137 struct btrfs_device *device, 1138 u64 chunk_tree, u64 chunk_objectid, 1139 u64 chunk_offset, u64 start, u64 num_bytes) 1140 { 1141 int ret; 1142 struct btrfs_path *path; 1143 struct btrfs_root *root = device->dev_root; 1144 struct btrfs_dev_extent *extent; 1145 struct extent_buffer *leaf; 1146 struct btrfs_key key; 1147 1148 WARN_ON(!device->in_fs_metadata); 1149 WARN_ON(device->is_tgtdev_for_dev_replace); 1150 path = btrfs_alloc_path(); 1151 if (!path) 1152 return -ENOMEM; 1153 1154 key.objectid = device->devid; 1155 key.offset = start; 1156 key.type = BTRFS_DEV_EXTENT_KEY; 1157 ret = btrfs_insert_empty_item(trans, root, path, &key, 1158 sizeof(*extent)); 1159 if (ret) 1160 goto out; 1161 1162 leaf = path->nodes[0]; 1163 extent = btrfs_item_ptr(leaf, path->slots[0], 1164 struct btrfs_dev_extent); 1165 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree); 1166 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid); 1167 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); 1168 1169 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 1170 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent), 1171 BTRFS_UUID_SIZE); 1172 1173 btrfs_set_dev_extent_length(leaf, extent, num_bytes); 1174 btrfs_mark_buffer_dirty(leaf); 1175 out: 1176 btrfs_free_path(path); 1177 return ret; 1178 } 1179 1180 static noinline int find_next_chunk(struct btrfs_root *root, 1181 u64 objectid, u64 *offset) 1182 { 1183 struct btrfs_path *path; 1184 int ret; 1185 struct btrfs_key key; 1186 struct btrfs_chunk *chunk; 1187 struct btrfs_key found_key; 1188 1189 path = btrfs_alloc_path(); 1190 if (!path) 1191 return -ENOMEM; 1192 1193 key.objectid = objectid; 1194 key.offset = (u64)-1; 1195 key.type = BTRFS_CHUNK_ITEM_KEY; 1196 1197 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1198 if (ret < 0) 1199 goto error; 1200 1201 BUG_ON(ret == 0); /* Corruption */ 1202 1203 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY); 1204 if (ret) { 1205 *offset = 0; 1206 } else { 1207 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1208 path->slots[0]); 1209 if (found_key.objectid != objectid) 1210 *offset = 0; 1211 else { 1212 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], 1213 struct btrfs_chunk); 1214 *offset = found_key.offset + 1215 btrfs_chunk_length(path->nodes[0], chunk); 1216 } 1217 } 1218 ret = 0; 1219 error: 1220 btrfs_free_path(path); 1221 return ret; 1222 } 1223 1224 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid) 1225 { 1226 int ret; 1227 struct btrfs_key key; 1228 struct btrfs_key found_key; 1229 struct btrfs_path *path; 1230 1231 root = root->fs_info->chunk_root; 1232 1233 path = btrfs_alloc_path(); 1234 if (!path) 1235 return -ENOMEM; 1236 1237 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1238 key.type = BTRFS_DEV_ITEM_KEY; 1239 key.offset = (u64)-1; 1240 1241 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1242 if (ret < 0) 1243 goto error; 1244 1245 BUG_ON(ret == 0); /* Corruption */ 1246 1247 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID, 1248 BTRFS_DEV_ITEM_KEY); 1249 if (ret) { 1250 *objectid = 1; 1251 } else { 1252 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1253 path->slots[0]); 1254 *objectid = found_key.offset + 1; 1255 } 1256 ret = 0; 1257 error: 1258 btrfs_free_path(path); 1259 return ret; 1260 } 1261 1262 /* 1263 * the device information is stored in the chunk root 1264 * the btrfs_device struct should be fully filled in 1265 */ 1266 int btrfs_add_device(struct btrfs_trans_handle *trans, 1267 struct btrfs_root *root, 1268 struct btrfs_device *device) 1269 { 1270 int ret; 1271 struct btrfs_path *path; 1272 struct btrfs_dev_item *dev_item; 1273 struct extent_buffer *leaf; 1274 struct btrfs_key key; 1275 unsigned long ptr; 1276 1277 root = root->fs_info->chunk_root; 1278 1279 path = btrfs_alloc_path(); 1280 if (!path) 1281 return -ENOMEM; 1282 1283 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1284 key.type = BTRFS_DEV_ITEM_KEY; 1285 key.offset = device->devid; 1286 1287 ret = btrfs_insert_empty_item(trans, root, path, &key, 1288 sizeof(*dev_item)); 1289 if (ret) 1290 goto out; 1291 1292 leaf = path->nodes[0]; 1293 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 1294 1295 btrfs_set_device_id(leaf, dev_item, device->devid); 1296 btrfs_set_device_generation(leaf, dev_item, 0); 1297 btrfs_set_device_type(leaf, dev_item, device->type); 1298 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 1299 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 1300 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 1301 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); 1302 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 1303 btrfs_set_device_group(leaf, dev_item, 0); 1304 btrfs_set_device_seek_speed(leaf, dev_item, 0); 1305 btrfs_set_device_bandwidth(leaf, dev_item, 0); 1306 btrfs_set_device_start_offset(leaf, dev_item, 0); 1307 1308 ptr = (unsigned long)btrfs_device_uuid(dev_item); 1309 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 1310 ptr = (unsigned long)btrfs_device_fsid(dev_item); 1311 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE); 1312 btrfs_mark_buffer_dirty(leaf); 1313 1314 ret = 0; 1315 out: 1316 btrfs_free_path(path); 1317 return ret; 1318 } 1319 1320 static int btrfs_rm_dev_item(struct btrfs_root *root, 1321 struct btrfs_device *device) 1322 { 1323 int ret; 1324 struct btrfs_path *path; 1325 struct btrfs_key key; 1326 struct btrfs_trans_handle *trans; 1327 1328 root = root->fs_info->chunk_root; 1329 1330 path = btrfs_alloc_path(); 1331 if (!path) 1332 return -ENOMEM; 1333 1334 trans = btrfs_start_transaction(root, 0); 1335 if (IS_ERR(trans)) { 1336 btrfs_free_path(path); 1337 return PTR_ERR(trans); 1338 } 1339 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1340 key.type = BTRFS_DEV_ITEM_KEY; 1341 key.offset = device->devid; 1342 lock_chunks(root); 1343 1344 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1345 if (ret < 0) 1346 goto out; 1347 1348 if (ret > 0) { 1349 ret = -ENOENT; 1350 goto out; 1351 } 1352 1353 ret = btrfs_del_item(trans, root, path); 1354 if (ret) 1355 goto out; 1356 out: 1357 btrfs_free_path(path); 1358 unlock_chunks(root); 1359 btrfs_commit_transaction(trans, root); 1360 return ret; 1361 } 1362 1363 int btrfs_rm_device(struct btrfs_root *root, char *device_path) 1364 { 1365 struct btrfs_device *device; 1366 struct btrfs_device *next_device; 1367 struct block_device *bdev; 1368 struct buffer_head *bh = NULL; 1369 struct btrfs_super_block *disk_super; 1370 struct btrfs_fs_devices *cur_devices; 1371 u64 all_avail; 1372 u64 devid; 1373 u64 num_devices; 1374 u8 *dev_uuid; 1375 int ret = 0; 1376 bool clear_super = false; 1377 1378 mutex_lock(&uuid_mutex); 1379 1380 all_avail = root->fs_info->avail_data_alloc_bits | 1381 root->fs_info->avail_system_alloc_bits | 1382 root->fs_info->avail_metadata_alloc_bits; 1383 1384 num_devices = root->fs_info->fs_devices->num_devices; 1385 btrfs_dev_replace_lock(&root->fs_info->dev_replace); 1386 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) { 1387 WARN_ON(num_devices < 1); 1388 num_devices--; 1389 } 1390 btrfs_dev_replace_unlock(&root->fs_info->dev_replace); 1391 1392 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) { 1393 printk(KERN_ERR "btrfs: unable to go below four devices " 1394 "on raid10\n"); 1395 ret = -EINVAL; 1396 goto out; 1397 } 1398 1399 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) { 1400 printk(KERN_ERR "btrfs: unable to go below two " 1401 "devices on raid1\n"); 1402 ret = -EINVAL; 1403 goto out; 1404 } 1405 1406 if (strcmp(device_path, "missing") == 0) { 1407 struct list_head *devices; 1408 struct btrfs_device *tmp; 1409 1410 device = NULL; 1411 devices = &root->fs_info->fs_devices->devices; 1412 /* 1413 * It is safe to read the devices since the volume_mutex 1414 * is held. 1415 */ 1416 list_for_each_entry(tmp, devices, dev_list) { 1417 if (tmp->in_fs_metadata && 1418 !tmp->is_tgtdev_for_dev_replace && 1419 !tmp->bdev) { 1420 device = tmp; 1421 break; 1422 } 1423 } 1424 bdev = NULL; 1425 bh = NULL; 1426 disk_super = NULL; 1427 if (!device) { 1428 printk(KERN_ERR "btrfs: no missing devices found to " 1429 "remove\n"); 1430 goto out; 1431 } 1432 } else { 1433 ret = btrfs_get_bdev_and_sb(device_path, 1434 FMODE_WRITE | FMODE_EXCL, 1435 root->fs_info->bdev_holder, 0, 1436 &bdev, &bh); 1437 if (ret) 1438 goto out; 1439 disk_super = (struct btrfs_super_block *)bh->b_data; 1440 devid = btrfs_stack_device_id(&disk_super->dev_item); 1441 dev_uuid = disk_super->dev_item.uuid; 1442 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1443 disk_super->fsid); 1444 if (!device) { 1445 ret = -ENOENT; 1446 goto error_brelse; 1447 } 1448 } 1449 1450 if (device->is_tgtdev_for_dev_replace) { 1451 pr_err("btrfs: unable to remove the dev_replace target dev\n"); 1452 ret = -EINVAL; 1453 goto error_brelse; 1454 } 1455 1456 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) { 1457 printk(KERN_ERR "btrfs: unable to remove the only writeable " 1458 "device\n"); 1459 ret = -EINVAL; 1460 goto error_brelse; 1461 } 1462 1463 if (device->writeable) { 1464 lock_chunks(root); 1465 list_del_init(&device->dev_alloc_list); 1466 unlock_chunks(root); 1467 root->fs_info->fs_devices->rw_devices--; 1468 clear_super = true; 1469 } 1470 1471 ret = btrfs_shrink_device(device, 0); 1472 if (ret) 1473 goto error_undo; 1474 1475 /* 1476 * TODO: the superblock still includes this device in its num_devices 1477 * counter although write_all_supers() is not locked out. This 1478 * could give a filesystem state which requires a degraded mount. 1479 */ 1480 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); 1481 if (ret) 1482 goto error_undo; 1483 1484 spin_lock(&root->fs_info->free_chunk_lock); 1485 root->fs_info->free_chunk_space = device->total_bytes - 1486 device->bytes_used; 1487 spin_unlock(&root->fs_info->free_chunk_lock); 1488 1489 device->in_fs_metadata = 0; 1490 btrfs_scrub_cancel_dev(root->fs_info, device); 1491 1492 /* 1493 * the device list mutex makes sure that we don't change 1494 * the device list while someone else is writing out all 1495 * the device supers. 1496 */ 1497 1498 cur_devices = device->fs_devices; 1499 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1500 list_del_rcu(&device->dev_list); 1501 1502 device->fs_devices->num_devices--; 1503 device->fs_devices->total_devices--; 1504 1505 if (device->missing) 1506 root->fs_info->fs_devices->missing_devices--; 1507 1508 next_device = list_entry(root->fs_info->fs_devices->devices.next, 1509 struct btrfs_device, dev_list); 1510 if (device->bdev == root->fs_info->sb->s_bdev) 1511 root->fs_info->sb->s_bdev = next_device->bdev; 1512 if (device->bdev == root->fs_info->fs_devices->latest_bdev) 1513 root->fs_info->fs_devices->latest_bdev = next_device->bdev; 1514 1515 if (device->bdev) 1516 device->fs_devices->open_devices--; 1517 1518 call_rcu(&device->rcu, free_device); 1519 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1520 1521 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1; 1522 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices); 1523 1524 if (cur_devices->open_devices == 0) { 1525 struct btrfs_fs_devices *fs_devices; 1526 fs_devices = root->fs_info->fs_devices; 1527 while (fs_devices) { 1528 if (fs_devices->seed == cur_devices) 1529 break; 1530 fs_devices = fs_devices->seed; 1531 } 1532 fs_devices->seed = cur_devices->seed; 1533 cur_devices->seed = NULL; 1534 lock_chunks(root); 1535 __btrfs_close_devices(cur_devices); 1536 unlock_chunks(root); 1537 free_fs_devices(cur_devices); 1538 } 1539 1540 root->fs_info->num_tolerated_disk_barrier_failures = 1541 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 1542 1543 /* 1544 * at this point, the device is zero sized. We want to 1545 * remove it from the devices list and zero out the old super 1546 */ 1547 if (clear_super && disk_super) { 1548 /* make sure this device isn't detected as part of 1549 * the FS anymore 1550 */ 1551 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 1552 set_buffer_dirty(bh); 1553 sync_dirty_buffer(bh); 1554 } 1555 1556 ret = 0; 1557 1558 /* Notify udev that device has changed */ 1559 if (bdev) 1560 btrfs_kobject_uevent(bdev, KOBJ_CHANGE); 1561 1562 error_brelse: 1563 brelse(bh); 1564 if (bdev) 1565 blkdev_put(bdev, FMODE_READ | FMODE_EXCL); 1566 out: 1567 mutex_unlock(&uuid_mutex); 1568 return ret; 1569 error_undo: 1570 if (device->writeable) { 1571 lock_chunks(root); 1572 list_add(&device->dev_alloc_list, 1573 &root->fs_info->fs_devices->alloc_list); 1574 unlock_chunks(root); 1575 root->fs_info->fs_devices->rw_devices++; 1576 } 1577 goto error_brelse; 1578 } 1579 1580 void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info, 1581 struct btrfs_device *srcdev) 1582 { 1583 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex)); 1584 list_del_rcu(&srcdev->dev_list); 1585 list_del_rcu(&srcdev->dev_alloc_list); 1586 fs_info->fs_devices->num_devices--; 1587 if (srcdev->missing) { 1588 fs_info->fs_devices->missing_devices--; 1589 fs_info->fs_devices->rw_devices++; 1590 } 1591 if (srcdev->can_discard) 1592 fs_info->fs_devices->num_can_discard--; 1593 if (srcdev->bdev) 1594 fs_info->fs_devices->open_devices--; 1595 1596 call_rcu(&srcdev->rcu, free_device); 1597 } 1598 1599 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 1600 struct btrfs_device *tgtdev) 1601 { 1602 struct btrfs_device *next_device; 1603 1604 WARN_ON(!tgtdev); 1605 mutex_lock(&fs_info->fs_devices->device_list_mutex); 1606 if (tgtdev->bdev) { 1607 btrfs_scratch_superblock(tgtdev); 1608 fs_info->fs_devices->open_devices--; 1609 } 1610 fs_info->fs_devices->num_devices--; 1611 if (tgtdev->can_discard) 1612 fs_info->fs_devices->num_can_discard++; 1613 1614 next_device = list_entry(fs_info->fs_devices->devices.next, 1615 struct btrfs_device, dev_list); 1616 if (tgtdev->bdev == fs_info->sb->s_bdev) 1617 fs_info->sb->s_bdev = next_device->bdev; 1618 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev) 1619 fs_info->fs_devices->latest_bdev = next_device->bdev; 1620 list_del_rcu(&tgtdev->dev_list); 1621 1622 call_rcu(&tgtdev->rcu, free_device); 1623 1624 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 1625 } 1626 1627 int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path, 1628 struct btrfs_device **device) 1629 { 1630 int ret = 0; 1631 struct btrfs_super_block *disk_super; 1632 u64 devid; 1633 u8 *dev_uuid; 1634 struct block_device *bdev; 1635 struct buffer_head *bh; 1636 1637 *device = NULL; 1638 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ, 1639 root->fs_info->bdev_holder, 0, &bdev, &bh); 1640 if (ret) 1641 return ret; 1642 disk_super = (struct btrfs_super_block *)bh->b_data; 1643 devid = btrfs_stack_device_id(&disk_super->dev_item); 1644 dev_uuid = disk_super->dev_item.uuid; 1645 *device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1646 disk_super->fsid); 1647 brelse(bh); 1648 if (!*device) 1649 ret = -ENOENT; 1650 blkdev_put(bdev, FMODE_READ); 1651 return ret; 1652 } 1653 1654 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root, 1655 char *device_path, 1656 struct btrfs_device **device) 1657 { 1658 *device = NULL; 1659 if (strcmp(device_path, "missing") == 0) { 1660 struct list_head *devices; 1661 struct btrfs_device *tmp; 1662 1663 devices = &root->fs_info->fs_devices->devices; 1664 /* 1665 * It is safe to read the devices since the volume_mutex 1666 * is held by the caller. 1667 */ 1668 list_for_each_entry(tmp, devices, dev_list) { 1669 if (tmp->in_fs_metadata && !tmp->bdev) { 1670 *device = tmp; 1671 break; 1672 } 1673 } 1674 1675 if (!*device) { 1676 pr_err("btrfs: no missing device found\n"); 1677 return -ENOENT; 1678 } 1679 1680 return 0; 1681 } else { 1682 return btrfs_find_device_by_path(root, device_path, device); 1683 } 1684 } 1685 1686 /* 1687 * does all the dirty work required for changing file system's UUID. 1688 */ 1689 static int btrfs_prepare_sprout(struct btrfs_root *root) 1690 { 1691 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 1692 struct btrfs_fs_devices *old_devices; 1693 struct btrfs_fs_devices *seed_devices; 1694 struct btrfs_super_block *disk_super = root->fs_info->super_copy; 1695 struct btrfs_device *device; 1696 u64 super_flags; 1697 1698 BUG_ON(!mutex_is_locked(&uuid_mutex)); 1699 if (!fs_devices->seeding) 1700 return -EINVAL; 1701 1702 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 1703 if (!seed_devices) 1704 return -ENOMEM; 1705 1706 old_devices = clone_fs_devices(fs_devices); 1707 if (IS_ERR(old_devices)) { 1708 kfree(seed_devices); 1709 return PTR_ERR(old_devices); 1710 } 1711 1712 list_add(&old_devices->list, &fs_uuids); 1713 1714 memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); 1715 seed_devices->opened = 1; 1716 INIT_LIST_HEAD(&seed_devices->devices); 1717 INIT_LIST_HEAD(&seed_devices->alloc_list); 1718 mutex_init(&seed_devices->device_list_mutex); 1719 1720 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1721 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, 1722 synchronize_rcu); 1723 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1724 1725 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); 1726 list_for_each_entry(device, &seed_devices->devices, dev_list) { 1727 device->fs_devices = seed_devices; 1728 } 1729 1730 fs_devices->seeding = 0; 1731 fs_devices->num_devices = 0; 1732 fs_devices->open_devices = 0; 1733 fs_devices->total_devices = 0; 1734 fs_devices->seed = seed_devices; 1735 1736 generate_random_uuid(fs_devices->fsid); 1737 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1738 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1739 super_flags = btrfs_super_flags(disk_super) & 1740 ~BTRFS_SUPER_FLAG_SEEDING; 1741 btrfs_set_super_flags(disk_super, super_flags); 1742 1743 return 0; 1744 } 1745 1746 /* 1747 * strore the expected generation for seed devices in device items. 1748 */ 1749 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans, 1750 struct btrfs_root *root) 1751 { 1752 struct btrfs_path *path; 1753 struct extent_buffer *leaf; 1754 struct btrfs_dev_item *dev_item; 1755 struct btrfs_device *device; 1756 struct btrfs_key key; 1757 u8 fs_uuid[BTRFS_UUID_SIZE]; 1758 u8 dev_uuid[BTRFS_UUID_SIZE]; 1759 u64 devid; 1760 int ret; 1761 1762 path = btrfs_alloc_path(); 1763 if (!path) 1764 return -ENOMEM; 1765 1766 root = root->fs_info->chunk_root; 1767 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1768 key.offset = 0; 1769 key.type = BTRFS_DEV_ITEM_KEY; 1770 1771 while (1) { 1772 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 1773 if (ret < 0) 1774 goto error; 1775 1776 leaf = path->nodes[0]; 1777 next_slot: 1778 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1779 ret = btrfs_next_leaf(root, path); 1780 if (ret > 0) 1781 break; 1782 if (ret < 0) 1783 goto error; 1784 leaf = path->nodes[0]; 1785 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1786 btrfs_release_path(path); 1787 continue; 1788 } 1789 1790 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1791 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || 1792 key.type != BTRFS_DEV_ITEM_KEY) 1793 break; 1794 1795 dev_item = btrfs_item_ptr(leaf, path->slots[0], 1796 struct btrfs_dev_item); 1797 devid = btrfs_device_id(leaf, dev_item); 1798 read_extent_buffer(leaf, dev_uuid, 1799 (unsigned long)btrfs_device_uuid(dev_item), 1800 BTRFS_UUID_SIZE); 1801 read_extent_buffer(leaf, fs_uuid, 1802 (unsigned long)btrfs_device_fsid(dev_item), 1803 BTRFS_UUID_SIZE); 1804 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1805 fs_uuid); 1806 BUG_ON(!device); /* Logic error */ 1807 1808 if (device->fs_devices->seeding) { 1809 btrfs_set_device_generation(leaf, dev_item, 1810 device->generation); 1811 btrfs_mark_buffer_dirty(leaf); 1812 } 1813 1814 path->slots[0]++; 1815 goto next_slot; 1816 } 1817 ret = 0; 1818 error: 1819 btrfs_free_path(path); 1820 return ret; 1821 } 1822 1823 int btrfs_init_new_device(struct btrfs_root *root, char *device_path) 1824 { 1825 struct request_queue *q; 1826 struct btrfs_trans_handle *trans; 1827 struct btrfs_device *device; 1828 struct block_device *bdev; 1829 struct list_head *devices; 1830 struct super_block *sb = root->fs_info->sb; 1831 struct rcu_string *name; 1832 u64 total_bytes; 1833 int seeding_dev = 0; 1834 int ret = 0; 1835 1836 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) 1837 return -EROFS; 1838 1839 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 1840 root->fs_info->bdev_holder); 1841 if (IS_ERR(bdev)) 1842 return PTR_ERR(bdev); 1843 1844 if (root->fs_info->fs_devices->seeding) { 1845 seeding_dev = 1; 1846 down_write(&sb->s_umount); 1847 mutex_lock(&uuid_mutex); 1848 } 1849 1850 filemap_write_and_wait(bdev->bd_inode->i_mapping); 1851 1852 devices = &root->fs_info->fs_devices->devices; 1853 1854 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1855 list_for_each_entry(device, devices, dev_list) { 1856 if (device->bdev == bdev) { 1857 ret = -EEXIST; 1858 mutex_unlock( 1859 &root->fs_info->fs_devices->device_list_mutex); 1860 goto error; 1861 } 1862 } 1863 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1864 1865 device = kzalloc(sizeof(*device), GFP_NOFS); 1866 if (!device) { 1867 /* we can safely leave the fs_devices entry around */ 1868 ret = -ENOMEM; 1869 goto error; 1870 } 1871 1872 name = rcu_string_strdup(device_path, GFP_NOFS); 1873 if (!name) { 1874 kfree(device); 1875 ret = -ENOMEM; 1876 goto error; 1877 } 1878 rcu_assign_pointer(device->name, name); 1879 1880 ret = find_next_devid(root, &device->devid); 1881 if (ret) { 1882 rcu_string_free(device->name); 1883 kfree(device); 1884 goto error; 1885 } 1886 1887 trans = btrfs_start_transaction(root, 0); 1888 if (IS_ERR(trans)) { 1889 rcu_string_free(device->name); 1890 kfree(device); 1891 ret = PTR_ERR(trans); 1892 goto error; 1893 } 1894 1895 lock_chunks(root); 1896 1897 q = bdev_get_queue(bdev); 1898 if (blk_queue_discard(q)) 1899 device->can_discard = 1; 1900 device->writeable = 1; 1901 device->work.func = pending_bios_fn; 1902 generate_random_uuid(device->uuid); 1903 spin_lock_init(&device->io_lock); 1904 device->generation = trans->transid; 1905 device->io_width = root->sectorsize; 1906 device->io_align = root->sectorsize; 1907 device->sector_size = root->sectorsize; 1908 device->total_bytes = i_size_read(bdev->bd_inode); 1909 device->disk_total_bytes = device->total_bytes; 1910 device->dev_root = root->fs_info->dev_root; 1911 device->bdev = bdev; 1912 device->in_fs_metadata = 1; 1913 device->is_tgtdev_for_dev_replace = 0; 1914 device->mode = FMODE_EXCL; 1915 set_blocksize(device->bdev, 4096); 1916 1917 if (seeding_dev) { 1918 sb->s_flags &= ~MS_RDONLY; 1919 ret = btrfs_prepare_sprout(root); 1920 BUG_ON(ret); /* -ENOMEM */ 1921 } 1922 1923 device->fs_devices = root->fs_info->fs_devices; 1924 1925 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1926 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices); 1927 list_add(&device->dev_alloc_list, 1928 &root->fs_info->fs_devices->alloc_list); 1929 root->fs_info->fs_devices->num_devices++; 1930 root->fs_info->fs_devices->open_devices++; 1931 root->fs_info->fs_devices->rw_devices++; 1932 root->fs_info->fs_devices->total_devices++; 1933 if (device->can_discard) 1934 root->fs_info->fs_devices->num_can_discard++; 1935 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes; 1936 1937 spin_lock(&root->fs_info->free_chunk_lock); 1938 root->fs_info->free_chunk_space += device->total_bytes; 1939 spin_unlock(&root->fs_info->free_chunk_lock); 1940 1941 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 1942 root->fs_info->fs_devices->rotating = 1; 1943 1944 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); 1945 btrfs_set_super_total_bytes(root->fs_info->super_copy, 1946 total_bytes + device->total_bytes); 1947 1948 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy); 1949 btrfs_set_super_num_devices(root->fs_info->super_copy, 1950 total_bytes + 1); 1951 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1952 1953 if (seeding_dev) { 1954 ret = init_first_rw_device(trans, root, device); 1955 if (ret) { 1956 btrfs_abort_transaction(trans, root, ret); 1957 goto error_trans; 1958 } 1959 ret = btrfs_finish_sprout(trans, root); 1960 if (ret) { 1961 btrfs_abort_transaction(trans, root, ret); 1962 goto error_trans; 1963 } 1964 } else { 1965 ret = btrfs_add_device(trans, root, device); 1966 if (ret) { 1967 btrfs_abort_transaction(trans, root, ret); 1968 goto error_trans; 1969 } 1970 } 1971 1972 /* 1973 * we've got more storage, clear any full flags on the space 1974 * infos 1975 */ 1976 btrfs_clear_space_info_full(root->fs_info); 1977 1978 unlock_chunks(root); 1979 root->fs_info->num_tolerated_disk_barrier_failures = 1980 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 1981 ret = btrfs_commit_transaction(trans, root); 1982 1983 if (seeding_dev) { 1984 mutex_unlock(&uuid_mutex); 1985 up_write(&sb->s_umount); 1986 1987 if (ret) /* transaction commit */ 1988 return ret; 1989 1990 ret = btrfs_relocate_sys_chunks(root); 1991 if (ret < 0) 1992 btrfs_error(root->fs_info, ret, 1993 "Failed to relocate sys chunks after " 1994 "device initialization. This can be fixed " 1995 "using the \"btrfs balance\" command."); 1996 trans = btrfs_attach_transaction(root); 1997 if (IS_ERR(trans)) { 1998 if (PTR_ERR(trans) == -ENOENT) 1999 return 0; 2000 return PTR_ERR(trans); 2001 } 2002 ret = btrfs_commit_transaction(trans, root); 2003 } 2004 2005 return ret; 2006 2007 error_trans: 2008 unlock_chunks(root); 2009 btrfs_end_transaction(trans, root); 2010 rcu_string_free(device->name); 2011 kfree(device); 2012 error: 2013 blkdev_put(bdev, FMODE_EXCL); 2014 if (seeding_dev) { 2015 mutex_unlock(&uuid_mutex); 2016 up_write(&sb->s_umount); 2017 } 2018 return ret; 2019 } 2020 2021 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path, 2022 struct btrfs_device **device_out) 2023 { 2024 struct request_queue *q; 2025 struct btrfs_device *device; 2026 struct block_device *bdev; 2027 struct btrfs_fs_info *fs_info = root->fs_info; 2028 struct list_head *devices; 2029 struct rcu_string *name; 2030 int ret = 0; 2031 2032 *device_out = NULL; 2033 if (fs_info->fs_devices->seeding) 2034 return -EINVAL; 2035 2036 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 2037 fs_info->bdev_holder); 2038 if (IS_ERR(bdev)) 2039 return PTR_ERR(bdev); 2040 2041 filemap_write_and_wait(bdev->bd_inode->i_mapping); 2042 2043 devices = &fs_info->fs_devices->devices; 2044 list_for_each_entry(device, devices, dev_list) { 2045 if (device->bdev == bdev) { 2046 ret = -EEXIST; 2047 goto error; 2048 } 2049 } 2050 2051 device = kzalloc(sizeof(*device), GFP_NOFS); 2052 if (!device) { 2053 ret = -ENOMEM; 2054 goto error; 2055 } 2056 2057 name = rcu_string_strdup(device_path, GFP_NOFS); 2058 if (!name) { 2059 kfree(device); 2060 ret = -ENOMEM; 2061 goto error; 2062 } 2063 rcu_assign_pointer(device->name, name); 2064 2065 q = bdev_get_queue(bdev); 2066 if (blk_queue_discard(q)) 2067 device->can_discard = 1; 2068 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2069 device->writeable = 1; 2070 device->work.func = pending_bios_fn; 2071 generate_random_uuid(device->uuid); 2072 device->devid = BTRFS_DEV_REPLACE_DEVID; 2073 spin_lock_init(&device->io_lock); 2074 device->generation = 0; 2075 device->io_width = root->sectorsize; 2076 device->io_align = root->sectorsize; 2077 device->sector_size = root->sectorsize; 2078 device->total_bytes = i_size_read(bdev->bd_inode); 2079 device->disk_total_bytes = device->total_bytes; 2080 device->dev_root = fs_info->dev_root; 2081 device->bdev = bdev; 2082 device->in_fs_metadata = 1; 2083 device->is_tgtdev_for_dev_replace = 1; 2084 device->mode = FMODE_EXCL; 2085 set_blocksize(device->bdev, 4096); 2086 device->fs_devices = fs_info->fs_devices; 2087 list_add(&device->dev_list, &fs_info->fs_devices->devices); 2088 fs_info->fs_devices->num_devices++; 2089 fs_info->fs_devices->open_devices++; 2090 if (device->can_discard) 2091 fs_info->fs_devices->num_can_discard++; 2092 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2093 2094 *device_out = device; 2095 return ret; 2096 2097 error: 2098 blkdev_put(bdev, FMODE_EXCL); 2099 return ret; 2100 } 2101 2102 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, 2103 struct btrfs_device *tgtdev) 2104 { 2105 WARN_ON(fs_info->fs_devices->rw_devices == 0); 2106 tgtdev->io_width = fs_info->dev_root->sectorsize; 2107 tgtdev->io_align = fs_info->dev_root->sectorsize; 2108 tgtdev->sector_size = fs_info->dev_root->sectorsize; 2109 tgtdev->dev_root = fs_info->dev_root; 2110 tgtdev->in_fs_metadata = 1; 2111 } 2112 2113 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, 2114 struct btrfs_device *device) 2115 { 2116 int ret; 2117 struct btrfs_path *path; 2118 struct btrfs_root *root; 2119 struct btrfs_dev_item *dev_item; 2120 struct extent_buffer *leaf; 2121 struct btrfs_key key; 2122 2123 root = device->dev_root->fs_info->chunk_root; 2124 2125 path = btrfs_alloc_path(); 2126 if (!path) 2127 return -ENOMEM; 2128 2129 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 2130 key.type = BTRFS_DEV_ITEM_KEY; 2131 key.offset = device->devid; 2132 2133 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2134 if (ret < 0) 2135 goto out; 2136 2137 if (ret > 0) { 2138 ret = -ENOENT; 2139 goto out; 2140 } 2141 2142 leaf = path->nodes[0]; 2143 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 2144 2145 btrfs_set_device_id(leaf, dev_item, device->devid); 2146 btrfs_set_device_type(leaf, dev_item, device->type); 2147 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 2148 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 2149 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 2150 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes); 2151 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 2152 btrfs_mark_buffer_dirty(leaf); 2153 2154 out: 2155 btrfs_free_path(path); 2156 return ret; 2157 } 2158 2159 static int __btrfs_grow_device(struct btrfs_trans_handle *trans, 2160 struct btrfs_device *device, u64 new_size) 2161 { 2162 struct btrfs_super_block *super_copy = 2163 device->dev_root->fs_info->super_copy; 2164 u64 old_total = btrfs_super_total_bytes(super_copy); 2165 u64 diff = new_size - device->total_bytes; 2166 2167 if (!device->writeable) 2168 return -EACCES; 2169 if (new_size <= device->total_bytes || 2170 device->is_tgtdev_for_dev_replace) 2171 return -EINVAL; 2172 2173 btrfs_set_super_total_bytes(super_copy, old_total + diff); 2174 device->fs_devices->total_rw_bytes += diff; 2175 2176 device->total_bytes = new_size; 2177 device->disk_total_bytes = new_size; 2178 btrfs_clear_space_info_full(device->dev_root->fs_info); 2179 2180 return btrfs_update_device(trans, device); 2181 } 2182 2183 int btrfs_grow_device(struct btrfs_trans_handle *trans, 2184 struct btrfs_device *device, u64 new_size) 2185 { 2186 int ret; 2187 lock_chunks(device->dev_root); 2188 ret = __btrfs_grow_device(trans, device, new_size); 2189 unlock_chunks(device->dev_root); 2190 return ret; 2191 } 2192 2193 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, 2194 struct btrfs_root *root, 2195 u64 chunk_tree, u64 chunk_objectid, 2196 u64 chunk_offset) 2197 { 2198 int ret; 2199 struct btrfs_path *path; 2200 struct btrfs_key key; 2201 2202 root = root->fs_info->chunk_root; 2203 path = btrfs_alloc_path(); 2204 if (!path) 2205 return -ENOMEM; 2206 2207 key.objectid = chunk_objectid; 2208 key.offset = chunk_offset; 2209 key.type = BTRFS_CHUNK_ITEM_KEY; 2210 2211 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2212 if (ret < 0) 2213 goto out; 2214 else if (ret > 0) { /* Logic error or corruption */ 2215 btrfs_error(root->fs_info, -ENOENT, 2216 "Failed lookup while freeing chunk."); 2217 ret = -ENOENT; 2218 goto out; 2219 } 2220 2221 ret = btrfs_del_item(trans, root, path); 2222 if (ret < 0) 2223 btrfs_error(root->fs_info, ret, 2224 "Failed to delete chunk item."); 2225 out: 2226 btrfs_free_path(path); 2227 return ret; 2228 } 2229 2230 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 2231 chunk_offset) 2232 { 2233 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 2234 struct btrfs_disk_key *disk_key; 2235 struct btrfs_chunk *chunk; 2236 u8 *ptr; 2237 int ret = 0; 2238 u32 num_stripes; 2239 u32 array_size; 2240 u32 len = 0; 2241 u32 cur; 2242 struct btrfs_key key; 2243 2244 array_size = btrfs_super_sys_array_size(super_copy); 2245 2246 ptr = super_copy->sys_chunk_array; 2247 cur = 0; 2248 2249 while (cur < array_size) { 2250 disk_key = (struct btrfs_disk_key *)ptr; 2251 btrfs_disk_key_to_cpu(&key, disk_key); 2252 2253 len = sizeof(*disk_key); 2254 2255 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 2256 chunk = (struct btrfs_chunk *)(ptr + len); 2257 num_stripes = btrfs_stack_chunk_num_stripes(chunk); 2258 len += btrfs_chunk_item_size(num_stripes); 2259 } else { 2260 ret = -EIO; 2261 break; 2262 } 2263 if (key.objectid == chunk_objectid && 2264 key.offset == chunk_offset) { 2265 memmove(ptr, ptr + len, array_size - (cur + len)); 2266 array_size -= len; 2267 btrfs_set_super_sys_array_size(super_copy, array_size); 2268 } else { 2269 ptr += len; 2270 cur += len; 2271 } 2272 } 2273 return ret; 2274 } 2275 2276 static int btrfs_relocate_chunk(struct btrfs_root *root, 2277 u64 chunk_tree, u64 chunk_objectid, 2278 u64 chunk_offset) 2279 { 2280 struct extent_map_tree *em_tree; 2281 struct btrfs_root *extent_root; 2282 struct btrfs_trans_handle *trans; 2283 struct extent_map *em; 2284 struct map_lookup *map; 2285 int ret; 2286 int i; 2287 2288 root = root->fs_info->chunk_root; 2289 extent_root = root->fs_info->extent_root; 2290 em_tree = &root->fs_info->mapping_tree.map_tree; 2291 2292 ret = btrfs_can_relocate(extent_root, chunk_offset); 2293 if (ret) 2294 return -ENOSPC; 2295 2296 /* step one, relocate all the extents inside this chunk */ 2297 ret = btrfs_relocate_block_group(extent_root, chunk_offset); 2298 if (ret) 2299 return ret; 2300 2301 trans = btrfs_start_transaction(root, 0); 2302 BUG_ON(IS_ERR(trans)); 2303 2304 lock_chunks(root); 2305 2306 /* 2307 * step two, delete the device extents and the 2308 * chunk tree entries 2309 */ 2310 read_lock(&em_tree->lock); 2311 em = lookup_extent_mapping(em_tree, chunk_offset, 1); 2312 read_unlock(&em_tree->lock); 2313 2314 BUG_ON(!em || em->start > chunk_offset || 2315 em->start + em->len < chunk_offset); 2316 map = (struct map_lookup *)em->bdev; 2317 2318 for (i = 0; i < map->num_stripes; i++) { 2319 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, 2320 map->stripes[i].physical); 2321 BUG_ON(ret); 2322 2323 if (map->stripes[i].dev) { 2324 ret = btrfs_update_device(trans, map->stripes[i].dev); 2325 BUG_ON(ret); 2326 } 2327 } 2328 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, 2329 chunk_offset); 2330 2331 BUG_ON(ret); 2332 2333 trace_btrfs_chunk_free(root, map, chunk_offset, em->len); 2334 2335 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 2336 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); 2337 BUG_ON(ret); 2338 } 2339 2340 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset); 2341 BUG_ON(ret); 2342 2343 write_lock(&em_tree->lock); 2344 remove_extent_mapping(em_tree, em); 2345 write_unlock(&em_tree->lock); 2346 2347 kfree(map); 2348 em->bdev = NULL; 2349 2350 /* once for the tree */ 2351 free_extent_map(em); 2352 /* once for us */ 2353 free_extent_map(em); 2354 2355 unlock_chunks(root); 2356 btrfs_end_transaction(trans, root); 2357 return 0; 2358 } 2359 2360 static int btrfs_relocate_sys_chunks(struct btrfs_root *root) 2361 { 2362 struct btrfs_root *chunk_root = root->fs_info->chunk_root; 2363 struct btrfs_path *path; 2364 struct extent_buffer *leaf; 2365 struct btrfs_chunk *chunk; 2366 struct btrfs_key key; 2367 struct btrfs_key found_key; 2368 u64 chunk_tree = chunk_root->root_key.objectid; 2369 u64 chunk_type; 2370 bool retried = false; 2371 int failed = 0; 2372 int ret; 2373 2374 path = btrfs_alloc_path(); 2375 if (!path) 2376 return -ENOMEM; 2377 2378 again: 2379 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2380 key.offset = (u64)-1; 2381 key.type = BTRFS_CHUNK_ITEM_KEY; 2382 2383 while (1) { 2384 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2385 if (ret < 0) 2386 goto error; 2387 BUG_ON(ret == 0); /* Corruption */ 2388 2389 ret = btrfs_previous_item(chunk_root, path, key.objectid, 2390 key.type); 2391 if (ret < 0) 2392 goto error; 2393 if (ret > 0) 2394 break; 2395 2396 leaf = path->nodes[0]; 2397 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2398 2399 chunk = btrfs_item_ptr(leaf, path->slots[0], 2400 struct btrfs_chunk); 2401 chunk_type = btrfs_chunk_type(leaf, chunk); 2402 btrfs_release_path(path); 2403 2404 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { 2405 ret = btrfs_relocate_chunk(chunk_root, chunk_tree, 2406 found_key.objectid, 2407 found_key.offset); 2408 if (ret == -ENOSPC) 2409 failed++; 2410 else if (ret) 2411 BUG(); 2412 } 2413 2414 if (found_key.offset == 0) 2415 break; 2416 key.offset = found_key.offset - 1; 2417 } 2418 ret = 0; 2419 if (failed && !retried) { 2420 failed = 0; 2421 retried = true; 2422 goto again; 2423 } else if (failed && retried) { 2424 WARN_ON(1); 2425 ret = -ENOSPC; 2426 } 2427 error: 2428 btrfs_free_path(path); 2429 return ret; 2430 } 2431 2432 static int insert_balance_item(struct btrfs_root *root, 2433 struct btrfs_balance_control *bctl) 2434 { 2435 struct btrfs_trans_handle *trans; 2436 struct btrfs_balance_item *item; 2437 struct btrfs_disk_balance_args disk_bargs; 2438 struct btrfs_path *path; 2439 struct extent_buffer *leaf; 2440 struct btrfs_key key; 2441 int ret, err; 2442 2443 path = btrfs_alloc_path(); 2444 if (!path) 2445 return -ENOMEM; 2446 2447 trans = btrfs_start_transaction(root, 0); 2448 if (IS_ERR(trans)) { 2449 btrfs_free_path(path); 2450 return PTR_ERR(trans); 2451 } 2452 2453 key.objectid = BTRFS_BALANCE_OBJECTID; 2454 key.type = BTRFS_BALANCE_ITEM_KEY; 2455 key.offset = 0; 2456 2457 ret = btrfs_insert_empty_item(trans, root, path, &key, 2458 sizeof(*item)); 2459 if (ret) 2460 goto out; 2461 2462 leaf = path->nodes[0]; 2463 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 2464 2465 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); 2466 2467 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); 2468 btrfs_set_balance_data(leaf, item, &disk_bargs); 2469 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); 2470 btrfs_set_balance_meta(leaf, item, &disk_bargs); 2471 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); 2472 btrfs_set_balance_sys(leaf, item, &disk_bargs); 2473 2474 btrfs_set_balance_flags(leaf, item, bctl->flags); 2475 2476 btrfs_mark_buffer_dirty(leaf); 2477 out: 2478 btrfs_free_path(path); 2479 err = btrfs_commit_transaction(trans, root); 2480 if (err && !ret) 2481 ret = err; 2482 return ret; 2483 } 2484 2485 static int del_balance_item(struct btrfs_root *root) 2486 { 2487 struct btrfs_trans_handle *trans; 2488 struct btrfs_path *path; 2489 struct btrfs_key key; 2490 int ret, err; 2491 2492 path = btrfs_alloc_path(); 2493 if (!path) 2494 return -ENOMEM; 2495 2496 trans = btrfs_start_transaction(root, 0); 2497 if (IS_ERR(trans)) { 2498 btrfs_free_path(path); 2499 return PTR_ERR(trans); 2500 } 2501 2502 key.objectid = BTRFS_BALANCE_OBJECTID; 2503 key.type = BTRFS_BALANCE_ITEM_KEY; 2504 key.offset = 0; 2505 2506 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2507 if (ret < 0) 2508 goto out; 2509 if (ret > 0) { 2510 ret = -ENOENT; 2511 goto out; 2512 } 2513 2514 ret = btrfs_del_item(trans, root, path); 2515 out: 2516 btrfs_free_path(path); 2517 err = btrfs_commit_transaction(trans, root); 2518 if (err && !ret) 2519 ret = err; 2520 return ret; 2521 } 2522 2523 /* 2524 * This is a heuristic used to reduce the number of chunks balanced on 2525 * resume after balance was interrupted. 2526 */ 2527 static void update_balance_args(struct btrfs_balance_control *bctl) 2528 { 2529 /* 2530 * Turn on soft mode for chunk types that were being converted. 2531 */ 2532 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) 2533 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; 2534 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) 2535 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; 2536 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) 2537 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; 2538 2539 /* 2540 * Turn on usage filter if is not already used. The idea is 2541 * that chunks that we have already balanced should be 2542 * reasonably full. Don't do it for chunks that are being 2543 * converted - that will keep us from relocating unconverted 2544 * (albeit full) chunks. 2545 */ 2546 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && 2547 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2548 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; 2549 bctl->data.usage = 90; 2550 } 2551 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && 2552 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2553 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; 2554 bctl->sys.usage = 90; 2555 } 2556 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && 2557 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2558 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; 2559 bctl->meta.usage = 90; 2560 } 2561 } 2562 2563 /* 2564 * Should be called with both balance and volume mutexes held to 2565 * serialize other volume operations (add_dev/rm_dev/resize) with 2566 * restriper. Same goes for unset_balance_control. 2567 */ 2568 static void set_balance_control(struct btrfs_balance_control *bctl) 2569 { 2570 struct btrfs_fs_info *fs_info = bctl->fs_info; 2571 2572 BUG_ON(fs_info->balance_ctl); 2573 2574 spin_lock(&fs_info->balance_lock); 2575 fs_info->balance_ctl = bctl; 2576 spin_unlock(&fs_info->balance_lock); 2577 } 2578 2579 static void unset_balance_control(struct btrfs_fs_info *fs_info) 2580 { 2581 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2582 2583 BUG_ON(!fs_info->balance_ctl); 2584 2585 spin_lock(&fs_info->balance_lock); 2586 fs_info->balance_ctl = NULL; 2587 spin_unlock(&fs_info->balance_lock); 2588 2589 kfree(bctl); 2590 } 2591 2592 /* 2593 * Balance filters. Return 1 if chunk should be filtered out 2594 * (should not be balanced). 2595 */ 2596 static int chunk_profiles_filter(u64 chunk_type, 2597 struct btrfs_balance_args *bargs) 2598 { 2599 chunk_type = chunk_to_extended(chunk_type) & 2600 BTRFS_EXTENDED_PROFILE_MASK; 2601 2602 if (bargs->profiles & chunk_type) 2603 return 0; 2604 2605 return 1; 2606 } 2607 2608 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, 2609 struct btrfs_balance_args *bargs) 2610 { 2611 struct btrfs_block_group_cache *cache; 2612 u64 chunk_used, user_thresh; 2613 int ret = 1; 2614 2615 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 2616 chunk_used = btrfs_block_group_used(&cache->item); 2617 2618 if (bargs->usage == 0) 2619 user_thresh = 0; 2620 else if (bargs->usage > 100) 2621 user_thresh = cache->key.offset; 2622 else 2623 user_thresh = div_factor_fine(cache->key.offset, 2624 bargs->usage); 2625 2626 if (chunk_used < user_thresh) 2627 ret = 0; 2628 2629 btrfs_put_block_group(cache); 2630 return ret; 2631 } 2632 2633 static int chunk_devid_filter(struct extent_buffer *leaf, 2634 struct btrfs_chunk *chunk, 2635 struct btrfs_balance_args *bargs) 2636 { 2637 struct btrfs_stripe *stripe; 2638 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2639 int i; 2640 2641 for (i = 0; i < num_stripes; i++) { 2642 stripe = btrfs_stripe_nr(chunk, i); 2643 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) 2644 return 0; 2645 } 2646 2647 return 1; 2648 } 2649 2650 /* [pstart, pend) */ 2651 static int chunk_drange_filter(struct extent_buffer *leaf, 2652 struct btrfs_chunk *chunk, 2653 u64 chunk_offset, 2654 struct btrfs_balance_args *bargs) 2655 { 2656 struct btrfs_stripe *stripe; 2657 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2658 u64 stripe_offset; 2659 u64 stripe_length; 2660 int factor; 2661 int i; 2662 2663 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) 2664 return 0; 2665 2666 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP | 2667 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) 2668 factor = 2; 2669 else 2670 factor = 1; 2671 factor = num_stripes / factor; 2672 2673 for (i = 0; i < num_stripes; i++) { 2674 stripe = btrfs_stripe_nr(chunk, i); 2675 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) 2676 continue; 2677 2678 stripe_offset = btrfs_stripe_offset(leaf, stripe); 2679 stripe_length = btrfs_chunk_length(leaf, chunk); 2680 do_div(stripe_length, factor); 2681 2682 if (stripe_offset < bargs->pend && 2683 stripe_offset + stripe_length > bargs->pstart) 2684 return 0; 2685 } 2686 2687 return 1; 2688 } 2689 2690 /* [vstart, vend) */ 2691 static int chunk_vrange_filter(struct extent_buffer *leaf, 2692 struct btrfs_chunk *chunk, 2693 u64 chunk_offset, 2694 struct btrfs_balance_args *bargs) 2695 { 2696 if (chunk_offset < bargs->vend && 2697 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) 2698 /* at least part of the chunk is inside this vrange */ 2699 return 0; 2700 2701 return 1; 2702 } 2703 2704 static int chunk_soft_convert_filter(u64 chunk_type, 2705 struct btrfs_balance_args *bargs) 2706 { 2707 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) 2708 return 0; 2709 2710 chunk_type = chunk_to_extended(chunk_type) & 2711 BTRFS_EXTENDED_PROFILE_MASK; 2712 2713 if (bargs->target == chunk_type) 2714 return 1; 2715 2716 return 0; 2717 } 2718 2719 static int should_balance_chunk(struct btrfs_root *root, 2720 struct extent_buffer *leaf, 2721 struct btrfs_chunk *chunk, u64 chunk_offset) 2722 { 2723 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl; 2724 struct btrfs_balance_args *bargs = NULL; 2725 u64 chunk_type = btrfs_chunk_type(leaf, chunk); 2726 2727 /* type filter */ 2728 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & 2729 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { 2730 return 0; 2731 } 2732 2733 if (chunk_type & BTRFS_BLOCK_GROUP_DATA) 2734 bargs = &bctl->data; 2735 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) 2736 bargs = &bctl->sys; 2737 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) 2738 bargs = &bctl->meta; 2739 2740 /* profiles filter */ 2741 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && 2742 chunk_profiles_filter(chunk_type, bargs)) { 2743 return 0; 2744 } 2745 2746 /* usage filter */ 2747 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && 2748 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) { 2749 return 0; 2750 } 2751 2752 /* devid filter */ 2753 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && 2754 chunk_devid_filter(leaf, chunk, bargs)) { 2755 return 0; 2756 } 2757 2758 /* drange filter, makes sense only with devid filter */ 2759 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && 2760 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) { 2761 return 0; 2762 } 2763 2764 /* vrange filter */ 2765 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && 2766 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { 2767 return 0; 2768 } 2769 2770 /* soft profile changing mode */ 2771 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && 2772 chunk_soft_convert_filter(chunk_type, bargs)) { 2773 return 0; 2774 } 2775 2776 return 1; 2777 } 2778 2779 static int __btrfs_balance(struct btrfs_fs_info *fs_info) 2780 { 2781 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2782 struct btrfs_root *chunk_root = fs_info->chunk_root; 2783 struct btrfs_root *dev_root = fs_info->dev_root; 2784 struct list_head *devices; 2785 struct btrfs_device *device; 2786 u64 old_size; 2787 u64 size_to_free; 2788 struct btrfs_chunk *chunk; 2789 struct btrfs_path *path; 2790 struct btrfs_key key; 2791 struct btrfs_key found_key; 2792 struct btrfs_trans_handle *trans; 2793 struct extent_buffer *leaf; 2794 int slot; 2795 int ret; 2796 int enospc_errors = 0; 2797 bool counting = true; 2798 2799 /* step one make some room on all the devices */ 2800 devices = &fs_info->fs_devices->devices; 2801 list_for_each_entry(device, devices, dev_list) { 2802 old_size = device->total_bytes; 2803 size_to_free = div_factor(old_size, 1); 2804 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024); 2805 if (!device->writeable || 2806 device->total_bytes - device->bytes_used > size_to_free || 2807 device->is_tgtdev_for_dev_replace) 2808 continue; 2809 2810 ret = btrfs_shrink_device(device, old_size - size_to_free); 2811 if (ret == -ENOSPC) 2812 break; 2813 BUG_ON(ret); 2814 2815 trans = btrfs_start_transaction(dev_root, 0); 2816 BUG_ON(IS_ERR(trans)); 2817 2818 ret = btrfs_grow_device(trans, device, old_size); 2819 BUG_ON(ret); 2820 2821 btrfs_end_transaction(trans, dev_root); 2822 } 2823 2824 /* step two, relocate all the chunks */ 2825 path = btrfs_alloc_path(); 2826 if (!path) { 2827 ret = -ENOMEM; 2828 goto error; 2829 } 2830 2831 /* zero out stat counters */ 2832 spin_lock(&fs_info->balance_lock); 2833 memset(&bctl->stat, 0, sizeof(bctl->stat)); 2834 spin_unlock(&fs_info->balance_lock); 2835 again: 2836 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2837 key.offset = (u64)-1; 2838 key.type = BTRFS_CHUNK_ITEM_KEY; 2839 2840 while (1) { 2841 if ((!counting && atomic_read(&fs_info->balance_pause_req)) || 2842 atomic_read(&fs_info->balance_cancel_req)) { 2843 ret = -ECANCELED; 2844 goto error; 2845 } 2846 2847 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2848 if (ret < 0) 2849 goto error; 2850 2851 /* 2852 * this shouldn't happen, it means the last relocate 2853 * failed 2854 */ 2855 if (ret == 0) 2856 BUG(); /* FIXME break ? */ 2857 2858 ret = btrfs_previous_item(chunk_root, path, 0, 2859 BTRFS_CHUNK_ITEM_KEY); 2860 if (ret) { 2861 ret = 0; 2862 break; 2863 } 2864 2865 leaf = path->nodes[0]; 2866 slot = path->slots[0]; 2867 btrfs_item_key_to_cpu(leaf, &found_key, slot); 2868 2869 if (found_key.objectid != key.objectid) 2870 break; 2871 2872 /* chunk zero is special */ 2873 if (found_key.offset == 0) 2874 break; 2875 2876 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 2877 2878 if (!counting) { 2879 spin_lock(&fs_info->balance_lock); 2880 bctl->stat.considered++; 2881 spin_unlock(&fs_info->balance_lock); 2882 } 2883 2884 ret = should_balance_chunk(chunk_root, leaf, chunk, 2885 found_key.offset); 2886 btrfs_release_path(path); 2887 if (!ret) 2888 goto loop; 2889 2890 if (counting) { 2891 spin_lock(&fs_info->balance_lock); 2892 bctl->stat.expected++; 2893 spin_unlock(&fs_info->balance_lock); 2894 goto loop; 2895 } 2896 2897 ret = btrfs_relocate_chunk(chunk_root, 2898 chunk_root->root_key.objectid, 2899 found_key.objectid, 2900 found_key.offset); 2901 if (ret && ret != -ENOSPC) 2902 goto error; 2903 if (ret == -ENOSPC) { 2904 enospc_errors++; 2905 } else { 2906 spin_lock(&fs_info->balance_lock); 2907 bctl->stat.completed++; 2908 spin_unlock(&fs_info->balance_lock); 2909 } 2910 loop: 2911 key.offset = found_key.offset - 1; 2912 } 2913 2914 if (counting) { 2915 btrfs_release_path(path); 2916 counting = false; 2917 goto again; 2918 } 2919 error: 2920 btrfs_free_path(path); 2921 if (enospc_errors) { 2922 printk(KERN_INFO "btrfs: %d enospc errors during balance\n", 2923 enospc_errors); 2924 if (!ret) 2925 ret = -ENOSPC; 2926 } 2927 2928 return ret; 2929 } 2930 2931 /** 2932 * alloc_profile_is_valid - see if a given profile is valid and reduced 2933 * @flags: profile to validate 2934 * @extended: if true @flags is treated as an extended profile 2935 */ 2936 static int alloc_profile_is_valid(u64 flags, int extended) 2937 { 2938 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK : 2939 BTRFS_BLOCK_GROUP_PROFILE_MASK); 2940 2941 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK; 2942 2943 /* 1) check that all other bits are zeroed */ 2944 if (flags & ~mask) 2945 return 0; 2946 2947 /* 2) see if profile is reduced */ 2948 if (flags == 0) 2949 return !extended; /* "0" is valid for usual profiles */ 2950 2951 /* true if exactly one bit set */ 2952 return (flags & (flags - 1)) == 0; 2953 } 2954 2955 static inline int balance_need_close(struct btrfs_fs_info *fs_info) 2956 { 2957 /* cancel requested || normal exit path */ 2958 return atomic_read(&fs_info->balance_cancel_req) || 2959 (atomic_read(&fs_info->balance_pause_req) == 0 && 2960 atomic_read(&fs_info->balance_cancel_req) == 0); 2961 } 2962 2963 static void __cancel_balance(struct btrfs_fs_info *fs_info) 2964 { 2965 int ret; 2966 2967 unset_balance_control(fs_info); 2968 ret = del_balance_item(fs_info->tree_root); 2969 BUG_ON(ret); 2970 2971 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 2972 } 2973 2974 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 2975 struct btrfs_ioctl_balance_args *bargs); 2976 2977 /* 2978 * Should be called with both balance and volume mutexes held 2979 */ 2980 int btrfs_balance(struct btrfs_balance_control *bctl, 2981 struct btrfs_ioctl_balance_args *bargs) 2982 { 2983 struct btrfs_fs_info *fs_info = bctl->fs_info; 2984 u64 allowed; 2985 int mixed = 0; 2986 int ret; 2987 u64 num_devices; 2988 2989 if (btrfs_fs_closing(fs_info) || 2990 atomic_read(&fs_info->balance_pause_req) || 2991 atomic_read(&fs_info->balance_cancel_req)) { 2992 ret = -EINVAL; 2993 goto out; 2994 } 2995 2996 allowed = btrfs_super_incompat_flags(fs_info->super_copy); 2997 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) 2998 mixed = 1; 2999 3000 /* 3001 * In case of mixed groups both data and meta should be picked, 3002 * and identical options should be given for both of them. 3003 */ 3004 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA; 3005 if (mixed && (bctl->flags & allowed)) { 3006 if (!(bctl->flags & BTRFS_BALANCE_DATA) || 3007 !(bctl->flags & BTRFS_BALANCE_METADATA) || 3008 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { 3009 printk(KERN_ERR "btrfs: with mixed groups data and " 3010 "metadata balance options must be the same\n"); 3011 ret = -EINVAL; 3012 goto out; 3013 } 3014 } 3015 3016 num_devices = fs_info->fs_devices->num_devices; 3017 btrfs_dev_replace_lock(&fs_info->dev_replace); 3018 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { 3019 BUG_ON(num_devices < 1); 3020 num_devices--; 3021 } 3022 btrfs_dev_replace_unlock(&fs_info->dev_replace); 3023 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; 3024 if (num_devices == 1) 3025 allowed |= BTRFS_BLOCK_GROUP_DUP; 3026 else if (num_devices < 4) 3027 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1); 3028 else 3029 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | 3030 BTRFS_BLOCK_GROUP_RAID10); 3031 3032 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3033 (!alloc_profile_is_valid(bctl->data.target, 1) || 3034 (bctl->data.target & ~allowed))) { 3035 printk(KERN_ERR "btrfs: unable to start balance with target " 3036 "data profile %llu\n", 3037 (unsigned long long)bctl->data.target); 3038 ret = -EINVAL; 3039 goto out; 3040 } 3041 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3042 (!alloc_profile_is_valid(bctl->meta.target, 1) || 3043 (bctl->meta.target & ~allowed))) { 3044 printk(KERN_ERR "btrfs: unable to start balance with target " 3045 "metadata profile %llu\n", 3046 (unsigned long long)bctl->meta.target); 3047 ret = -EINVAL; 3048 goto out; 3049 } 3050 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3051 (!alloc_profile_is_valid(bctl->sys.target, 1) || 3052 (bctl->sys.target & ~allowed))) { 3053 printk(KERN_ERR "btrfs: unable to start balance with target " 3054 "system profile %llu\n", 3055 (unsigned long long)bctl->sys.target); 3056 ret = -EINVAL; 3057 goto out; 3058 } 3059 3060 /* allow dup'ed data chunks only in mixed mode */ 3061 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3062 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) { 3063 printk(KERN_ERR "btrfs: dup for data is not allowed\n"); 3064 ret = -EINVAL; 3065 goto out; 3066 } 3067 3068 /* allow to reduce meta or sys integrity only if force set */ 3069 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | 3070 BTRFS_BLOCK_GROUP_RAID10; 3071 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3072 (fs_info->avail_system_alloc_bits & allowed) && 3073 !(bctl->sys.target & allowed)) || 3074 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3075 (fs_info->avail_metadata_alloc_bits & allowed) && 3076 !(bctl->meta.target & allowed))) { 3077 if (bctl->flags & BTRFS_BALANCE_FORCE) { 3078 printk(KERN_INFO "btrfs: force reducing metadata " 3079 "integrity\n"); 3080 } else { 3081 printk(KERN_ERR "btrfs: balance will reduce metadata " 3082 "integrity, use force if you want this\n"); 3083 ret = -EINVAL; 3084 goto out; 3085 } 3086 } 3087 3088 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3089 int num_tolerated_disk_barrier_failures; 3090 u64 target = bctl->sys.target; 3091 3092 num_tolerated_disk_barrier_failures = 3093 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3094 if (num_tolerated_disk_barrier_failures > 0 && 3095 (target & 3096 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 | 3097 BTRFS_AVAIL_ALLOC_BIT_SINGLE))) 3098 num_tolerated_disk_barrier_failures = 0; 3099 else if (num_tolerated_disk_barrier_failures > 1 && 3100 (target & 3101 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10))) 3102 num_tolerated_disk_barrier_failures = 1; 3103 3104 fs_info->num_tolerated_disk_barrier_failures = 3105 num_tolerated_disk_barrier_failures; 3106 } 3107 3108 ret = insert_balance_item(fs_info->tree_root, bctl); 3109 if (ret && ret != -EEXIST) 3110 goto out; 3111 3112 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { 3113 BUG_ON(ret == -EEXIST); 3114 set_balance_control(bctl); 3115 } else { 3116 BUG_ON(ret != -EEXIST); 3117 spin_lock(&fs_info->balance_lock); 3118 update_balance_args(bctl); 3119 spin_unlock(&fs_info->balance_lock); 3120 } 3121 3122 atomic_inc(&fs_info->balance_running); 3123 mutex_unlock(&fs_info->balance_mutex); 3124 3125 ret = __btrfs_balance(fs_info); 3126 3127 mutex_lock(&fs_info->balance_mutex); 3128 atomic_dec(&fs_info->balance_running); 3129 3130 if (bargs) { 3131 memset(bargs, 0, sizeof(*bargs)); 3132 update_ioctl_balance_args(fs_info, 0, bargs); 3133 } 3134 3135 if ((ret && ret != -ECANCELED && ret != -ENOSPC) || 3136 balance_need_close(fs_info)) { 3137 __cancel_balance(fs_info); 3138 } 3139 3140 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3141 fs_info->num_tolerated_disk_barrier_failures = 3142 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3143 } 3144 3145 wake_up(&fs_info->balance_wait_q); 3146 3147 return ret; 3148 out: 3149 if (bctl->flags & BTRFS_BALANCE_RESUME) 3150 __cancel_balance(fs_info); 3151 else { 3152 kfree(bctl); 3153 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3154 } 3155 return ret; 3156 } 3157 3158 static int balance_kthread(void *data) 3159 { 3160 struct btrfs_fs_info *fs_info = data; 3161 int ret = 0; 3162 3163 mutex_lock(&fs_info->volume_mutex); 3164 mutex_lock(&fs_info->balance_mutex); 3165 3166 if (fs_info->balance_ctl) { 3167 printk(KERN_INFO "btrfs: continuing balance\n"); 3168 ret = btrfs_balance(fs_info->balance_ctl, NULL); 3169 } 3170 3171 mutex_unlock(&fs_info->balance_mutex); 3172 mutex_unlock(&fs_info->volume_mutex); 3173 3174 return ret; 3175 } 3176 3177 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info) 3178 { 3179 struct task_struct *tsk; 3180 3181 spin_lock(&fs_info->balance_lock); 3182 if (!fs_info->balance_ctl) { 3183 spin_unlock(&fs_info->balance_lock); 3184 return 0; 3185 } 3186 spin_unlock(&fs_info->balance_lock); 3187 3188 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) { 3189 printk(KERN_INFO "btrfs: force skipping balance\n"); 3190 return 0; 3191 } 3192 3193 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance"); 3194 if (IS_ERR(tsk)) 3195 return PTR_ERR(tsk); 3196 3197 return 0; 3198 } 3199 3200 int btrfs_recover_balance(struct btrfs_fs_info *fs_info) 3201 { 3202 struct btrfs_balance_control *bctl; 3203 struct btrfs_balance_item *item; 3204 struct btrfs_disk_balance_args disk_bargs; 3205 struct btrfs_path *path; 3206 struct extent_buffer *leaf; 3207 struct btrfs_key key; 3208 int ret; 3209 3210 path = btrfs_alloc_path(); 3211 if (!path) 3212 return -ENOMEM; 3213 3214 key.objectid = BTRFS_BALANCE_OBJECTID; 3215 key.type = BTRFS_BALANCE_ITEM_KEY; 3216 key.offset = 0; 3217 3218 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 3219 if (ret < 0) 3220 goto out; 3221 if (ret > 0) { /* ret = -ENOENT; */ 3222 ret = 0; 3223 goto out; 3224 } 3225 3226 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3227 if (!bctl) { 3228 ret = -ENOMEM; 3229 goto out; 3230 } 3231 3232 leaf = path->nodes[0]; 3233 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 3234 3235 bctl->fs_info = fs_info; 3236 bctl->flags = btrfs_balance_flags(leaf, item); 3237 bctl->flags |= BTRFS_BALANCE_RESUME; 3238 3239 btrfs_balance_data(leaf, item, &disk_bargs); 3240 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); 3241 btrfs_balance_meta(leaf, item, &disk_bargs); 3242 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); 3243 btrfs_balance_sys(leaf, item, &disk_bargs); 3244 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); 3245 3246 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)); 3247 3248 mutex_lock(&fs_info->volume_mutex); 3249 mutex_lock(&fs_info->balance_mutex); 3250 3251 set_balance_control(bctl); 3252 3253 mutex_unlock(&fs_info->balance_mutex); 3254 mutex_unlock(&fs_info->volume_mutex); 3255 out: 3256 btrfs_free_path(path); 3257 return ret; 3258 } 3259 3260 int btrfs_pause_balance(struct btrfs_fs_info *fs_info) 3261 { 3262 int ret = 0; 3263 3264 mutex_lock(&fs_info->balance_mutex); 3265 if (!fs_info->balance_ctl) { 3266 mutex_unlock(&fs_info->balance_mutex); 3267 return -ENOTCONN; 3268 } 3269 3270 if (atomic_read(&fs_info->balance_running)) { 3271 atomic_inc(&fs_info->balance_pause_req); 3272 mutex_unlock(&fs_info->balance_mutex); 3273 3274 wait_event(fs_info->balance_wait_q, 3275 atomic_read(&fs_info->balance_running) == 0); 3276 3277 mutex_lock(&fs_info->balance_mutex); 3278 /* we are good with balance_ctl ripped off from under us */ 3279 BUG_ON(atomic_read(&fs_info->balance_running)); 3280 atomic_dec(&fs_info->balance_pause_req); 3281 } else { 3282 ret = -ENOTCONN; 3283 } 3284 3285 mutex_unlock(&fs_info->balance_mutex); 3286 return ret; 3287 } 3288 3289 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) 3290 { 3291 mutex_lock(&fs_info->balance_mutex); 3292 if (!fs_info->balance_ctl) { 3293 mutex_unlock(&fs_info->balance_mutex); 3294 return -ENOTCONN; 3295 } 3296 3297 atomic_inc(&fs_info->balance_cancel_req); 3298 /* 3299 * if we are running just wait and return, balance item is 3300 * deleted in btrfs_balance in this case 3301 */ 3302 if (atomic_read(&fs_info->balance_running)) { 3303 mutex_unlock(&fs_info->balance_mutex); 3304 wait_event(fs_info->balance_wait_q, 3305 atomic_read(&fs_info->balance_running) == 0); 3306 mutex_lock(&fs_info->balance_mutex); 3307 } else { 3308 /* __cancel_balance needs volume_mutex */ 3309 mutex_unlock(&fs_info->balance_mutex); 3310 mutex_lock(&fs_info->volume_mutex); 3311 mutex_lock(&fs_info->balance_mutex); 3312 3313 if (fs_info->balance_ctl) 3314 __cancel_balance(fs_info); 3315 3316 mutex_unlock(&fs_info->volume_mutex); 3317 } 3318 3319 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running)); 3320 atomic_dec(&fs_info->balance_cancel_req); 3321 mutex_unlock(&fs_info->balance_mutex); 3322 return 0; 3323 } 3324 3325 /* 3326 * shrinking a device means finding all of the device extents past 3327 * the new size, and then following the back refs to the chunks. 3328 * The chunk relocation code actually frees the device extent 3329 */ 3330 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 3331 { 3332 struct btrfs_trans_handle *trans; 3333 struct btrfs_root *root = device->dev_root; 3334 struct btrfs_dev_extent *dev_extent = NULL; 3335 struct btrfs_path *path; 3336 u64 length; 3337 u64 chunk_tree; 3338 u64 chunk_objectid; 3339 u64 chunk_offset; 3340 int ret; 3341 int slot; 3342 int failed = 0; 3343 bool retried = false; 3344 struct extent_buffer *l; 3345 struct btrfs_key key; 3346 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3347 u64 old_total = btrfs_super_total_bytes(super_copy); 3348 u64 old_size = device->total_bytes; 3349 u64 diff = device->total_bytes - new_size; 3350 3351 if (device->is_tgtdev_for_dev_replace) 3352 return -EINVAL; 3353 3354 path = btrfs_alloc_path(); 3355 if (!path) 3356 return -ENOMEM; 3357 3358 path->reada = 2; 3359 3360 lock_chunks(root); 3361 3362 device->total_bytes = new_size; 3363 if (device->writeable) { 3364 device->fs_devices->total_rw_bytes -= diff; 3365 spin_lock(&root->fs_info->free_chunk_lock); 3366 root->fs_info->free_chunk_space -= diff; 3367 spin_unlock(&root->fs_info->free_chunk_lock); 3368 } 3369 unlock_chunks(root); 3370 3371 again: 3372 key.objectid = device->devid; 3373 key.offset = (u64)-1; 3374 key.type = BTRFS_DEV_EXTENT_KEY; 3375 3376 do { 3377 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3378 if (ret < 0) 3379 goto done; 3380 3381 ret = btrfs_previous_item(root, path, 0, key.type); 3382 if (ret < 0) 3383 goto done; 3384 if (ret) { 3385 ret = 0; 3386 btrfs_release_path(path); 3387 break; 3388 } 3389 3390 l = path->nodes[0]; 3391 slot = path->slots[0]; 3392 btrfs_item_key_to_cpu(l, &key, path->slots[0]); 3393 3394 if (key.objectid != device->devid) { 3395 btrfs_release_path(path); 3396 break; 3397 } 3398 3399 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 3400 length = btrfs_dev_extent_length(l, dev_extent); 3401 3402 if (key.offset + length <= new_size) { 3403 btrfs_release_path(path); 3404 break; 3405 } 3406 3407 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); 3408 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); 3409 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); 3410 btrfs_release_path(path); 3411 3412 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, 3413 chunk_offset); 3414 if (ret && ret != -ENOSPC) 3415 goto done; 3416 if (ret == -ENOSPC) 3417 failed++; 3418 } while (key.offset-- > 0); 3419 3420 if (failed && !retried) { 3421 failed = 0; 3422 retried = true; 3423 goto again; 3424 } else if (failed && retried) { 3425 ret = -ENOSPC; 3426 lock_chunks(root); 3427 3428 device->total_bytes = old_size; 3429 if (device->writeable) 3430 device->fs_devices->total_rw_bytes += diff; 3431 spin_lock(&root->fs_info->free_chunk_lock); 3432 root->fs_info->free_chunk_space += diff; 3433 spin_unlock(&root->fs_info->free_chunk_lock); 3434 unlock_chunks(root); 3435 goto done; 3436 } 3437 3438 /* Shrinking succeeded, else we would be at "done". */ 3439 trans = btrfs_start_transaction(root, 0); 3440 if (IS_ERR(trans)) { 3441 ret = PTR_ERR(trans); 3442 goto done; 3443 } 3444 3445 lock_chunks(root); 3446 3447 device->disk_total_bytes = new_size; 3448 /* Now btrfs_update_device() will change the on-disk size. */ 3449 ret = btrfs_update_device(trans, device); 3450 if (ret) { 3451 unlock_chunks(root); 3452 btrfs_end_transaction(trans, root); 3453 goto done; 3454 } 3455 WARN_ON(diff > old_total); 3456 btrfs_set_super_total_bytes(super_copy, old_total - diff); 3457 unlock_chunks(root); 3458 btrfs_end_transaction(trans, root); 3459 done: 3460 btrfs_free_path(path); 3461 return ret; 3462 } 3463 3464 static int btrfs_add_system_chunk(struct btrfs_root *root, 3465 struct btrfs_key *key, 3466 struct btrfs_chunk *chunk, int item_size) 3467 { 3468 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3469 struct btrfs_disk_key disk_key; 3470 u32 array_size; 3471 u8 *ptr; 3472 3473 array_size = btrfs_super_sys_array_size(super_copy); 3474 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) 3475 return -EFBIG; 3476 3477 ptr = super_copy->sys_chunk_array + array_size; 3478 btrfs_cpu_key_to_disk(&disk_key, key); 3479 memcpy(ptr, &disk_key, sizeof(disk_key)); 3480 ptr += sizeof(disk_key); 3481 memcpy(ptr, chunk, item_size); 3482 item_size += sizeof(disk_key); 3483 btrfs_set_super_sys_array_size(super_copy, array_size + item_size); 3484 return 0; 3485 } 3486 3487 /* 3488 * sort the devices in descending order by max_avail, total_avail 3489 */ 3490 static int btrfs_cmp_device_info(const void *a, const void *b) 3491 { 3492 const struct btrfs_device_info *di_a = a; 3493 const struct btrfs_device_info *di_b = b; 3494 3495 if (di_a->max_avail > di_b->max_avail) 3496 return -1; 3497 if (di_a->max_avail < di_b->max_avail) 3498 return 1; 3499 if (di_a->total_avail > di_b->total_avail) 3500 return -1; 3501 if (di_a->total_avail < di_b->total_avail) 3502 return 1; 3503 return 0; 3504 } 3505 3506 struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { 3507 { 2, 1, 0, 4, 2, 2 /* raid10 */ }, 3508 { 1, 1, 2, 2, 2, 2 /* raid1 */ }, 3509 { 1, 2, 1, 1, 1, 2 /* dup */ }, 3510 { 1, 1, 0, 2, 1, 1 /* raid0 */ }, 3511 { 1, 1, 1, 1, 1, 1 /* single */ }, 3512 }; 3513 3514 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 3515 struct btrfs_root *extent_root, 3516 struct map_lookup **map_ret, 3517 u64 *num_bytes_out, u64 *stripe_size_out, 3518 u64 start, u64 type) 3519 { 3520 struct btrfs_fs_info *info = extent_root->fs_info; 3521 struct btrfs_fs_devices *fs_devices = info->fs_devices; 3522 struct list_head *cur; 3523 struct map_lookup *map = NULL; 3524 struct extent_map_tree *em_tree; 3525 struct extent_map *em; 3526 struct btrfs_device_info *devices_info = NULL; 3527 u64 total_avail; 3528 int num_stripes; /* total number of stripes to allocate */ 3529 int sub_stripes; /* sub_stripes info for map */ 3530 int dev_stripes; /* stripes per dev */ 3531 int devs_max; /* max devs to use */ 3532 int devs_min; /* min devs needed */ 3533 int devs_increment; /* ndevs has to be a multiple of this */ 3534 int ncopies; /* how many copies to data has */ 3535 int ret; 3536 u64 max_stripe_size; 3537 u64 max_chunk_size; 3538 u64 stripe_size; 3539 u64 num_bytes; 3540 int ndevs; 3541 int i; 3542 int j; 3543 int index; 3544 3545 BUG_ON(!alloc_profile_is_valid(type, 0)); 3546 3547 if (list_empty(&fs_devices->alloc_list)) 3548 return -ENOSPC; 3549 3550 index = __get_raid_index(type); 3551 3552 sub_stripes = btrfs_raid_array[index].sub_stripes; 3553 dev_stripes = btrfs_raid_array[index].dev_stripes; 3554 devs_max = btrfs_raid_array[index].devs_max; 3555 devs_min = btrfs_raid_array[index].devs_min; 3556 devs_increment = btrfs_raid_array[index].devs_increment; 3557 ncopies = btrfs_raid_array[index].ncopies; 3558 3559 if (type & BTRFS_BLOCK_GROUP_DATA) { 3560 max_stripe_size = 1024 * 1024 * 1024; 3561 max_chunk_size = 10 * max_stripe_size; 3562 } else if (type & BTRFS_BLOCK_GROUP_METADATA) { 3563 /* for larger filesystems, use larger metadata chunks */ 3564 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024) 3565 max_stripe_size = 1024 * 1024 * 1024; 3566 else 3567 max_stripe_size = 256 * 1024 * 1024; 3568 max_chunk_size = max_stripe_size; 3569 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { 3570 max_stripe_size = 32 * 1024 * 1024; 3571 max_chunk_size = 2 * max_stripe_size; 3572 } else { 3573 printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n", 3574 type); 3575 BUG_ON(1); 3576 } 3577 3578 /* we don't want a chunk larger than 10% of writeable space */ 3579 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1), 3580 max_chunk_size); 3581 3582 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices, 3583 GFP_NOFS); 3584 if (!devices_info) 3585 return -ENOMEM; 3586 3587 cur = fs_devices->alloc_list.next; 3588 3589 /* 3590 * in the first pass through the devices list, we gather information 3591 * about the available holes on each device. 3592 */ 3593 ndevs = 0; 3594 while (cur != &fs_devices->alloc_list) { 3595 struct btrfs_device *device; 3596 u64 max_avail; 3597 u64 dev_offset; 3598 3599 device = list_entry(cur, struct btrfs_device, dev_alloc_list); 3600 3601 cur = cur->next; 3602 3603 if (!device->writeable) { 3604 WARN(1, KERN_ERR 3605 "btrfs: read-only device in alloc_list\n"); 3606 continue; 3607 } 3608 3609 if (!device->in_fs_metadata || 3610 device->is_tgtdev_for_dev_replace) 3611 continue; 3612 3613 if (device->total_bytes > device->bytes_used) 3614 total_avail = device->total_bytes - device->bytes_used; 3615 else 3616 total_avail = 0; 3617 3618 /* If there is no space on this device, skip it. */ 3619 if (total_avail == 0) 3620 continue; 3621 3622 ret = find_free_dev_extent(device, 3623 max_stripe_size * dev_stripes, 3624 &dev_offset, &max_avail); 3625 if (ret && ret != -ENOSPC) 3626 goto error; 3627 3628 if (ret == 0) 3629 max_avail = max_stripe_size * dev_stripes; 3630 3631 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes) 3632 continue; 3633 3634 devices_info[ndevs].dev_offset = dev_offset; 3635 devices_info[ndevs].max_avail = max_avail; 3636 devices_info[ndevs].total_avail = total_avail; 3637 devices_info[ndevs].dev = device; 3638 ++ndevs; 3639 WARN_ON(ndevs > fs_devices->rw_devices); 3640 } 3641 3642 /* 3643 * now sort the devices by hole size / available space 3644 */ 3645 sort(devices_info, ndevs, sizeof(struct btrfs_device_info), 3646 btrfs_cmp_device_info, NULL); 3647 3648 /* round down to number of usable stripes */ 3649 ndevs -= ndevs % devs_increment; 3650 3651 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) { 3652 ret = -ENOSPC; 3653 goto error; 3654 } 3655 3656 if (devs_max && ndevs > devs_max) 3657 ndevs = devs_max; 3658 /* 3659 * the primary goal is to maximize the number of stripes, so use as many 3660 * devices as possible, even if the stripes are not maximum sized. 3661 */ 3662 stripe_size = devices_info[ndevs-1].max_avail; 3663 num_stripes = ndevs * dev_stripes; 3664 3665 if (stripe_size * ndevs > max_chunk_size * ncopies) { 3666 stripe_size = max_chunk_size * ncopies; 3667 do_div(stripe_size, ndevs); 3668 } 3669 3670 do_div(stripe_size, dev_stripes); 3671 3672 /* align to BTRFS_STRIPE_LEN */ 3673 do_div(stripe_size, BTRFS_STRIPE_LEN); 3674 stripe_size *= BTRFS_STRIPE_LEN; 3675 3676 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 3677 if (!map) { 3678 ret = -ENOMEM; 3679 goto error; 3680 } 3681 map->num_stripes = num_stripes; 3682 3683 for (i = 0; i < ndevs; ++i) { 3684 for (j = 0; j < dev_stripes; ++j) { 3685 int s = i * dev_stripes + j; 3686 map->stripes[s].dev = devices_info[i].dev; 3687 map->stripes[s].physical = devices_info[i].dev_offset + 3688 j * stripe_size; 3689 } 3690 } 3691 map->sector_size = extent_root->sectorsize; 3692 map->stripe_len = BTRFS_STRIPE_LEN; 3693 map->io_align = BTRFS_STRIPE_LEN; 3694 map->io_width = BTRFS_STRIPE_LEN; 3695 map->type = type; 3696 map->sub_stripes = sub_stripes; 3697 3698 *map_ret = map; 3699 num_bytes = stripe_size * (num_stripes / ncopies); 3700 3701 *stripe_size_out = stripe_size; 3702 *num_bytes_out = num_bytes; 3703 3704 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes); 3705 3706 em = alloc_extent_map(); 3707 if (!em) { 3708 ret = -ENOMEM; 3709 goto error; 3710 } 3711 em->bdev = (struct block_device *)map; 3712 em->start = start; 3713 em->len = num_bytes; 3714 em->block_start = 0; 3715 em->block_len = em->len; 3716 3717 em_tree = &extent_root->fs_info->mapping_tree.map_tree; 3718 write_lock(&em_tree->lock); 3719 ret = add_extent_mapping(em_tree, em); 3720 write_unlock(&em_tree->lock); 3721 free_extent_map(em); 3722 if (ret) 3723 goto error; 3724 3725 ret = btrfs_make_block_group(trans, extent_root, 0, type, 3726 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3727 start, num_bytes); 3728 if (ret) 3729 goto error; 3730 3731 for (i = 0; i < map->num_stripes; ++i) { 3732 struct btrfs_device *device; 3733 u64 dev_offset; 3734 3735 device = map->stripes[i].dev; 3736 dev_offset = map->stripes[i].physical; 3737 3738 ret = btrfs_alloc_dev_extent(trans, device, 3739 info->chunk_root->root_key.objectid, 3740 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3741 start, dev_offset, stripe_size); 3742 if (ret) { 3743 btrfs_abort_transaction(trans, extent_root, ret); 3744 goto error; 3745 } 3746 } 3747 3748 kfree(devices_info); 3749 return 0; 3750 3751 error: 3752 kfree(map); 3753 kfree(devices_info); 3754 return ret; 3755 } 3756 3757 static int __finish_chunk_alloc(struct btrfs_trans_handle *trans, 3758 struct btrfs_root *extent_root, 3759 struct map_lookup *map, u64 chunk_offset, 3760 u64 chunk_size, u64 stripe_size) 3761 { 3762 u64 dev_offset; 3763 struct btrfs_key key; 3764 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 3765 struct btrfs_device *device; 3766 struct btrfs_chunk *chunk; 3767 struct btrfs_stripe *stripe; 3768 size_t item_size = btrfs_chunk_item_size(map->num_stripes); 3769 int index = 0; 3770 int ret; 3771 3772 chunk = kzalloc(item_size, GFP_NOFS); 3773 if (!chunk) 3774 return -ENOMEM; 3775 3776 index = 0; 3777 while (index < map->num_stripes) { 3778 device = map->stripes[index].dev; 3779 device->bytes_used += stripe_size; 3780 ret = btrfs_update_device(trans, device); 3781 if (ret) 3782 goto out_free; 3783 index++; 3784 } 3785 3786 spin_lock(&extent_root->fs_info->free_chunk_lock); 3787 extent_root->fs_info->free_chunk_space -= (stripe_size * 3788 map->num_stripes); 3789 spin_unlock(&extent_root->fs_info->free_chunk_lock); 3790 3791 index = 0; 3792 stripe = &chunk->stripe; 3793 while (index < map->num_stripes) { 3794 device = map->stripes[index].dev; 3795 dev_offset = map->stripes[index].physical; 3796 3797 btrfs_set_stack_stripe_devid(stripe, device->devid); 3798 btrfs_set_stack_stripe_offset(stripe, dev_offset); 3799 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); 3800 stripe++; 3801 index++; 3802 } 3803 3804 btrfs_set_stack_chunk_length(chunk, chunk_size); 3805 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); 3806 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); 3807 btrfs_set_stack_chunk_type(chunk, map->type); 3808 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); 3809 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); 3810 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); 3811 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); 3812 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); 3813 3814 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 3815 key.type = BTRFS_CHUNK_ITEM_KEY; 3816 key.offset = chunk_offset; 3817 3818 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); 3819 3820 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 3821 /* 3822 * TODO: Cleanup of inserted chunk root in case of 3823 * failure. 3824 */ 3825 ret = btrfs_add_system_chunk(chunk_root, &key, chunk, 3826 item_size); 3827 } 3828 3829 out_free: 3830 kfree(chunk); 3831 return ret; 3832 } 3833 3834 /* 3835 * Chunk allocation falls into two parts. The first part does works 3836 * that make the new allocated chunk useable, but not do any operation 3837 * that modifies the chunk tree. The second part does the works that 3838 * require modifying the chunk tree. This division is important for the 3839 * bootstrap process of adding storage to a seed btrfs. 3840 */ 3841 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 3842 struct btrfs_root *extent_root, u64 type) 3843 { 3844 u64 chunk_offset; 3845 u64 chunk_size; 3846 u64 stripe_size; 3847 struct map_lookup *map; 3848 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 3849 int ret; 3850 3851 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3852 &chunk_offset); 3853 if (ret) 3854 return ret; 3855 3856 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, 3857 &stripe_size, chunk_offset, type); 3858 if (ret) 3859 return ret; 3860 3861 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, 3862 chunk_size, stripe_size); 3863 if (ret) 3864 return ret; 3865 return 0; 3866 } 3867 3868 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans, 3869 struct btrfs_root *root, 3870 struct btrfs_device *device) 3871 { 3872 u64 chunk_offset; 3873 u64 sys_chunk_offset; 3874 u64 chunk_size; 3875 u64 sys_chunk_size; 3876 u64 stripe_size; 3877 u64 sys_stripe_size; 3878 u64 alloc_profile; 3879 struct map_lookup *map; 3880 struct map_lookup *sys_map; 3881 struct btrfs_fs_info *fs_info = root->fs_info; 3882 struct btrfs_root *extent_root = fs_info->extent_root; 3883 int ret; 3884 3885 ret = find_next_chunk(fs_info->chunk_root, 3886 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset); 3887 if (ret) 3888 return ret; 3889 3890 alloc_profile = BTRFS_BLOCK_GROUP_METADATA | 3891 fs_info->avail_metadata_alloc_bits; 3892 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile); 3893 3894 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, 3895 &stripe_size, chunk_offset, alloc_profile); 3896 if (ret) 3897 return ret; 3898 3899 sys_chunk_offset = chunk_offset + chunk_size; 3900 3901 alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM | 3902 fs_info->avail_system_alloc_bits; 3903 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile); 3904 3905 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map, 3906 &sys_chunk_size, &sys_stripe_size, 3907 sys_chunk_offset, alloc_profile); 3908 if (ret) { 3909 btrfs_abort_transaction(trans, root, ret); 3910 goto out; 3911 } 3912 3913 ret = btrfs_add_device(trans, fs_info->chunk_root, device); 3914 if (ret) { 3915 btrfs_abort_transaction(trans, root, ret); 3916 goto out; 3917 } 3918 3919 /* 3920 * Modifying chunk tree needs allocating new blocks from both 3921 * system block group and metadata block group. So we only can 3922 * do operations require modifying the chunk tree after both 3923 * block groups were created. 3924 */ 3925 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, 3926 chunk_size, stripe_size); 3927 if (ret) { 3928 btrfs_abort_transaction(trans, root, ret); 3929 goto out; 3930 } 3931 3932 ret = __finish_chunk_alloc(trans, extent_root, sys_map, 3933 sys_chunk_offset, sys_chunk_size, 3934 sys_stripe_size); 3935 if (ret) 3936 btrfs_abort_transaction(trans, root, ret); 3937 3938 out: 3939 3940 return ret; 3941 } 3942 3943 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) 3944 { 3945 struct extent_map *em; 3946 struct map_lookup *map; 3947 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 3948 int readonly = 0; 3949 int i; 3950 3951 read_lock(&map_tree->map_tree.lock); 3952 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); 3953 read_unlock(&map_tree->map_tree.lock); 3954 if (!em) 3955 return 1; 3956 3957 if (btrfs_test_opt(root, DEGRADED)) { 3958 free_extent_map(em); 3959 return 0; 3960 } 3961 3962 map = (struct map_lookup *)em->bdev; 3963 for (i = 0; i < map->num_stripes; i++) { 3964 if (!map->stripes[i].dev->writeable) { 3965 readonly = 1; 3966 break; 3967 } 3968 } 3969 free_extent_map(em); 3970 return readonly; 3971 } 3972 3973 void btrfs_mapping_init(struct btrfs_mapping_tree *tree) 3974 { 3975 extent_map_tree_init(&tree->map_tree); 3976 } 3977 3978 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree) 3979 { 3980 struct extent_map *em; 3981 3982 while (1) { 3983 write_lock(&tree->map_tree.lock); 3984 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1); 3985 if (em) 3986 remove_extent_mapping(&tree->map_tree, em); 3987 write_unlock(&tree->map_tree.lock); 3988 if (!em) 3989 break; 3990 kfree(em->bdev); 3991 /* once for us */ 3992 free_extent_map(em); 3993 /* once for the tree */ 3994 free_extent_map(em); 3995 } 3996 } 3997 3998 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) 3999 { 4000 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4001 struct extent_map *em; 4002 struct map_lookup *map; 4003 struct extent_map_tree *em_tree = &map_tree->map_tree; 4004 int ret; 4005 4006 read_lock(&em_tree->lock); 4007 em = lookup_extent_mapping(em_tree, logical, len); 4008 read_unlock(&em_tree->lock); 4009 BUG_ON(!em); 4010 4011 BUG_ON(em->start > logical || em->start + em->len < logical); 4012 map = (struct map_lookup *)em->bdev; 4013 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1)) 4014 ret = map->num_stripes; 4015 else if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4016 ret = map->sub_stripes; 4017 else 4018 ret = 1; 4019 free_extent_map(em); 4020 4021 btrfs_dev_replace_lock(&fs_info->dev_replace); 4022 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) 4023 ret++; 4024 btrfs_dev_replace_unlock(&fs_info->dev_replace); 4025 4026 return ret; 4027 } 4028 4029 static int find_live_mirror(struct btrfs_fs_info *fs_info, 4030 struct map_lookup *map, int first, int num, 4031 int optimal, int dev_replace_is_ongoing) 4032 { 4033 int i; 4034 int tolerance; 4035 struct btrfs_device *srcdev; 4036 4037 if (dev_replace_is_ongoing && 4038 fs_info->dev_replace.cont_reading_from_srcdev_mode == 4039 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID) 4040 srcdev = fs_info->dev_replace.srcdev; 4041 else 4042 srcdev = NULL; 4043 4044 /* 4045 * try to avoid the drive that is the source drive for a 4046 * dev-replace procedure, only choose it if no other non-missing 4047 * mirror is available 4048 */ 4049 for (tolerance = 0; tolerance < 2; tolerance++) { 4050 if (map->stripes[optimal].dev->bdev && 4051 (tolerance || map->stripes[optimal].dev != srcdev)) 4052 return optimal; 4053 for (i = first; i < first + num; i++) { 4054 if (map->stripes[i].dev->bdev && 4055 (tolerance || map->stripes[i].dev != srcdev)) 4056 return i; 4057 } 4058 } 4059 4060 /* we couldn't find one that doesn't fail. Just return something 4061 * and the io error handling code will clean up eventually 4062 */ 4063 return optimal; 4064 } 4065 4066 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4067 u64 logical, u64 *length, 4068 struct btrfs_bio **bbio_ret, 4069 int mirror_num) 4070 { 4071 struct extent_map *em; 4072 struct map_lookup *map; 4073 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4074 struct extent_map_tree *em_tree = &map_tree->map_tree; 4075 u64 offset; 4076 u64 stripe_offset; 4077 u64 stripe_end_offset; 4078 u64 stripe_nr; 4079 u64 stripe_nr_orig; 4080 u64 stripe_nr_end; 4081 int stripe_index; 4082 int i; 4083 int ret = 0; 4084 int num_stripes; 4085 int max_errors = 0; 4086 struct btrfs_bio *bbio = NULL; 4087 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 4088 int dev_replace_is_ongoing = 0; 4089 int num_alloc_stripes; 4090 int patch_the_first_stripe_for_dev_replace = 0; 4091 u64 physical_to_patch_in_first_stripe = 0; 4092 4093 read_lock(&em_tree->lock); 4094 em = lookup_extent_mapping(em_tree, logical, *length); 4095 read_unlock(&em_tree->lock); 4096 4097 if (!em) { 4098 printk(KERN_CRIT "btrfs: unable to find logical %llu len %llu\n", 4099 (unsigned long long)logical, 4100 (unsigned long long)*length); 4101 BUG(); 4102 } 4103 4104 BUG_ON(em->start > logical || em->start + em->len < logical); 4105 map = (struct map_lookup *)em->bdev; 4106 offset = logical - em->start; 4107 4108 stripe_nr = offset; 4109 /* 4110 * stripe_nr counts the total number of stripes we have to stride 4111 * to get to this block 4112 */ 4113 do_div(stripe_nr, map->stripe_len); 4114 4115 stripe_offset = stripe_nr * map->stripe_len; 4116 BUG_ON(offset < stripe_offset); 4117 4118 /* stripe_offset is the offset of this block in its stripe*/ 4119 stripe_offset = offset - stripe_offset; 4120 4121 if (rw & REQ_DISCARD) 4122 *length = min_t(u64, em->len - offset, *length); 4123 else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { 4124 /* we limit the length of each bio to what fits in a stripe */ 4125 *length = min_t(u64, em->len - offset, 4126 map->stripe_len - stripe_offset); 4127 } else { 4128 *length = em->len - offset; 4129 } 4130 4131 if (!bbio_ret) 4132 goto out; 4133 4134 btrfs_dev_replace_lock(dev_replace); 4135 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace); 4136 if (!dev_replace_is_ongoing) 4137 btrfs_dev_replace_unlock(dev_replace); 4138 4139 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 && 4140 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) && 4141 dev_replace->tgtdev != NULL) { 4142 /* 4143 * in dev-replace case, for repair case (that's the only 4144 * case where the mirror is selected explicitly when 4145 * calling btrfs_map_block), blocks left of the left cursor 4146 * can also be read from the target drive. 4147 * For REQ_GET_READ_MIRRORS, the target drive is added as 4148 * the last one to the array of stripes. For READ, it also 4149 * needs to be supported using the same mirror number. 4150 * If the requested block is not left of the left cursor, 4151 * EIO is returned. This can happen because btrfs_num_copies() 4152 * returns one more in the dev-replace case. 4153 */ 4154 u64 tmp_length = *length; 4155 struct btrfs_bio *tmp_bbio = NULL; 4156 int tmp_num_stripes; 4157 u64 srcdev_devid = dev_replace->srcdev->devid; 4158 int index_srcdev = 0; 4159 int found = 0; 4160 u64 physical_of_found = 0; 4161 4162 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, 4163 logical, &tmp_length, &tmp_bbio, 0); 4164 if (ret) { 4165 WARN_ON(tmp_bbio != NULL); 4166 goto out; 4167 } 4168 4169 tmp_num_stripes = tmp_bbio->num_stripes; 4170 if (mirror_num > tmp_num_stripes) { 4171 /* 4172 * REQ_GET_READ_MIRRORS does not contain this 4173 * mirror, that means that the requested area 4174 * is not left of the left cursor 4175 */ 4176 ret = -EIO; 4177 kfree(tmp_bbio); 4178 goto out; 4179 } 4180 4181 /* 4182 * process the rest of the function using the mirror_num 4183 * of the source drive. Therefore look it up first. 4184 * At the end, patch the device pointer to the one of the 4185 * target drive. 4186 */ 4187 for (i = 0; i < tmp_num_stripes; i++) { 4188 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) { 4189 /* 4190 * In case of DUP, in order to keep it 4191 * simple, only add the mirror with the 4192 * lowest physical address 4193 */ 4194 if (found && 4195 physical_of_found <= 4196 tmp_bbio->stripes[i].physical) 4197 continue; 4198 index_srcdev = i; 4199 found = 1; 4200 physical_of_found = 4201 tmp_bbio->stripes[i].physical; 4202 } 4203 } 4204 4205 if (found) { 4206 mirror_num = index_srcdev + 1; 4207 patch_the_first_stripe_for_dev_replace = 1; 4208 physical_to_patch_in_first_stripe = physical_of_found; 4209 } else { 4210 WARN_ON(1); 4211 ret = -EIO; 4212 kfree(tmp_bbio); 4213 goto out; 4214 } 4215 4216 kfree(tmp_bbio); 4217 } else if (mirror_num > map->num_stripes) { 4218 mirror_num = 0; 4219 } 4220 4221 num_stripes = 1; 4222 stripe_index = 0; 4223 stripe_nr_orig = stripe_nr; 4224 stripe_nr_end = (offset + *length + map->stripe_len - 1) & 4225 (~(map->stripe_len - 1)); 4226 do_div(stripe_nr_end, map->stripe_len); 4227 stripe_end_offset = stripe_nr_end * map->stripe_len - 4228 (offset + *length); 4229 if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4230 if (rw & REQ_DISCARD) 4231 num_stripes = min_t(u64, map->num_stripes, 4232 stripe_nr_end - stripe_nr_orig); 4233 stripe_index = do_div(stripe_nr, map->num_stripes); 4234 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { 4235 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) 4236 num_stripes = map->num_stripes; 4237 else if (mirror_num) 4238 stripe_index = mirror_num - 1; 4239 else { 4240 stripe_index = find_live_mirror(fs_info, map, 0, 4241 map->num_stripes, 4242 current->pid % map->num_stripes, 4243 dev_replace_is_ongoing); 4244 mirror_num = stripe_index + 1; 4245 } 4246 4247 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { 4248 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) { 4249 num_stripes = map->num_stripes; 4250 } else if (mirror_num) { 4251 stripe_index = mirror_num - 1; 4252 } else { 4253 mirror_num = 1; 4254 } 4255 4256 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4257 int factor = map->num_stripes / map->sub_stripes; 4258 4259 stripe_index = do_div(stripe_nr, factor); 4260 stripe_index *= map->sub_stripes; 4261 4262 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) 4263 num_stripes = map->sub_stripes; 4264 else if (rw & REQ_DISCARD) 4265 num_stripes = min_t(u64, map->sub_stripes * 4266 (stripe_nr_end - stripe_nr_orig), 4267 map->num_stripes); 4268 else if (mirror_num) 4269 stripe_index += mirror_num - 1; 4270 else { 4271 int old_stripe_index = stripe_index; 4272 stripe_index = find_live_mirror(fs_info, map, 4273 stripe_index, 4274 map->sub_stripes, stripe_index + 4275 current->pid % map->sub_stripes, 4276 dev_replace_is_ongoing); 4277 mirror_num = stripe_index - old_stripe_index + 1; 4278 } 4279 } else { 4280 /* 4281 * after this do_div call, stripe_nr is the number of stripes 4282 * on this device we have to walk to find the data, and 4283 * stripe_index is the number of our device in the stripe array 4284 */ 4285 stripe_index = do_div(stripe_nr, map->num_stripes); 4286 mirror_num = stripe_index + 1; 4287 } 4288 BUG_ON(stripe_index >= map->num_stripes); 4289 4290 num_alloc_stripes = num_stripes; 4291 if (dev_replace_is_ongoing) { 4292 if (rw & (REQ_WRITE | REQ_DISCARD)) 4293 num_alloc_stripes <<= 1; 4294 if (rw & REQ_GET_READ_MIRRORS) 4295 num_alloc_stripes++; 4296 } 4297 bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS); 4298 if (!bbio) { 4299 ret = -ENOMEM; 4300 goto out; 4301 } 4302 atomic_set(&bbio->error, 0); 4303 4304 if (rw & REQ_DISCARD) { 4305 int factor = 0; 4306 int sub_stripes = 0; 4307 u64 stripes_per_dev = 0; 4308 u32 remaining_stripes = 0; 4309 u32 last_stripe = 0; 4310 4311 if (map->type & 4312 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { 4313 if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4314 sub_stripes = 1; 4315 else 4316 sub_stripes = map->sub_stripes; 4317 4318 factor = map->num_stripes / sub_stripes; 4319 stripes_per_dev = div_u64_rem(stripe_nr_end - 4320 stripe_nr_orig, 4321 factor, 4322 &remaining_stripes); 4323 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe); 4324 last_stripe *= sub_stripes; 4325 } 4326 4327 for (i = 0; i < num_stripes; i++) { 4328 bbio->stripes[i].physical = 4329 map->stripes[stripe_index].physical + 4330 stripe_offset + stripe_nr * map->stripe_len; 4331 bbio->stripes[i].dev = map->stripes[stripe_index].dev; 4332 4333 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | 4334 BTRFS_BLOCK_GROUP_RAID10)) { 4335 bbio->stripes[i].length = stripes_per_dev * 4336 map->stripe_len; 4337 4338 if (i / sub_stripes < remaining_stripes) 4339 bbio->stripes[i].length += 4340 map->stripe_len; 4341 4342 /* 4343 * Special for the first stripe and 4344 * the last stripe: 4345 * 4346 * |-------|...|-------| 4347 * |----------| 4348 * off end_off 4349 */ 4350 if (i < sub_stripes) 4351 bbio->stripes[i].length -= 4352 stripe_offset; 4353 4354 if (stripe_index >= last_stripe && 4355 stripe_index <= (last_stripe + 4356 sub_stripes - 1)) 4357 bbio->stripes[i].length -= 4358 stripe_end_offset; 4359 4360 if (i == sub_stripes - 1) 4361 stripe_offset = 0; 4362 } else 4363 bbio->stripes[i].length = *length; 4364 4365 stripe_index++; 4366 if (stripe_index == map->num_stripes) { 4367 /* This could only happen for RAID0/10 */ 4368 stripe_index = 0; 4369 stripe_nr++; 4370 } 4371 } 4372 } else { 4373 for (i = 0; i < num_stripes; i++) { 4374 bbio->stripes[i].physical = 4375 map->stripes[stripe_index].physical + 4376 stripe_offset + 4377 stripe_nr * map->stripe_len; 4378 bbio->stripes[i].dev = 4379 map->stripes[stripe_index].dev; 4380 stripe_index++; 4381 } 4382 } 4383 4384 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) { 4385 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | 4386 BTRFS_BLOCK_GROUP_RAID10 | 4387 BTRFS_BLOCK_GROUP_DUP)) { 4388 max_errors = 1; 4389 } 4390 } 4391 4392 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) && 4393 dev_replace->tgtdev != NULL) { 4394 int index_where_to_add; 4395 u64 srcdev_devid = dev_replace->srcdev->devid; 4396 4397 /* 4398 * duplicate the write operations while the dev replace 4399 * procedure is running. Since the copying of the old disk 4400 * to the new disk takes place at run time while the 4401 * filesystem is mounted writable, the regular write 4402 * operations to the old disk have to be duplicated to go 4403 * to the new disk as well. 4404 * Note that device->missing is handled by the caller, and 4405 * that the write to the old disk is already set up in the 4406 * stripes array. 4407 */ 4408 index_where_to_add = num_stripes; 4409 for (i = 0; i < num_stripes; i++) { 4410 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4411 /* write to new disk, too */ 4412 struct btrfs_bio_stripe *new = 4413 bbio->stripes + index_where_to_add; 4414 struct btrfs_bio_stripe *old = 4415 bbio->stripes + i; 4416 4417 new->physical = old->physical; 4418 new->length = old->length; 4419 new->dev = dev_replace->tgtdev; 4420 index_where_to_add++; 4421 max_errors++; 4422 } 4423 } 4424 num_stripes = index_where_to_add; 4425 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) && 4426 dev_replace->tgtdev != NULL) { 4427 u64 srcdev_devid = dev_replace->srcdev->devid; 4428 int index_srcdev = 0; 4429 int found = 0; 4430 u64 physical_of_found = 0; 4431 4432 /* 4433 * During the dev-replace procedure, the target drive can 4434 * also be used to read data in case it is needed to repair 4435 * a corrupt block elsewhere. This is possible if the 4436 * requested area is left of the left cursor. In this area, 4437 * the target drive is a full copy of the source drive. 4438 */ 4439 for (i = 0; i < num_stripes; i++) { 4440 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4441 /* 4442 * In case of DUP, in order to keep it 4443 * simple, only add the mirror with the 4444 * lowest physical address 4445 */ 4446 if (found && 4447 physical_of_found <= 4448 bbio->stripes[i].physical) 4449 continue; 4450 index_srcdev = i; 4451 found = 1; 4452 physical_of_found = bbio->stripes[i].physical; 4453 } 4454 } 4455 if (found) { 4456 u64 length = map->stripe_len; 4457 4458 if (physical_of_found + length <= 4459 dev_replace->cursor_left) { 4460 struct btrfs_bio_stripe *tgtdev_stripe = 4461 bbio->stripes + num_stripes; 4462 4463 tgtdev_stripe->physical = physical_of_found; 4464 tgtdev_stripe->length = 4465 bbio->stripes[index_srcdev].length; 4466 tgtdev_stripe->dev = dev_replace->tgtdev; 4467 4468 num_stripes++; 4469 } 4470 } 4471 } 4472 4473 *bbio_ret = bbio; 4474 bbio->num_stripes = num_stripes; 4475 bbio->max_errors = max_errors; 4476 bbio->mirror_num = mirror_num; 4477 4478 /* 4479 * this is the case that REQ_READ && dev_replace_is_ongoing && 4480 * mirror_num == num_stripes + 1 && dev_replace target drive is 4481 * available as a mirror 4482 */ 4483 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) { 4484 WARN_ON(num_stripes > 1); 4485 bbio->stripes[0].dev = dev_replace->tgtdev; 4486 bbio->stripes[0].physical = physical_to_patch_in_first_stripe; 4487 bbio->mirror_num = map->num_stripes + 1; 4488 } 4489 out: 4490 if (dev_replace_is_ongoing) 4491 btrfs_dev_replace_unlock(dev_replace); 4492 free_extent_map(em); 4493 return ret; 4494 } 4495 4496 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4497 u64 logical, u64 *length, 4498 struct btrfs_bio **bbio_ret, int mirror_num) 4499 { 4500 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret, 4501 mirror_num); 4502 } 4503 4504 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, 4505 u64 chunk_start, u64 physical, u64 devid, 4506 u64 **logical, int *naddrs, int *stripe_len) 4507 { 4508 struct extent_map_tree *em_tree = &map_tree->map_tree; 4509 struct extent_map *em; 4510 struct map_lookup *map; 4511 u64 *buf; 4512 u64 bytenr; 4513 u64 length; 4514 u64 stripe_nr; 4515 int i, j, nr = 0; 4516 4517 read_lock(&em_tree->lock); 4518 em = lookup_extent_mapping(em_tree, chunk_start, 1); 4519 read_unlock(&em_tree->lock); 4520 4521 BUG_ON(!em || em->start != chunk_start); 4522 map = (struct map_lookup *)em->bdev; 4523 4524 length = em->len; 4525 if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4526 do_div(length, map->num_stripes / map->sub_stripes); 4527 else if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4528 do_div(length, map->num_stripes); 4529 4530 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); 4531 BUG_ON(!buf); /* -ENOMEM */ 4532 4533 for (i = 0; i < map->num_stripes; i++) { 4534 if (devid && map->stripes[i].dev->devid != devid) 4535 continue; 4536 if (map->stripes[i].physical > physical || 4537 map->stripes[i].physical + length <= physical) 4538 continue; 4539 4540 stripe_nr = physical - map->stripes[i].physical; 4541 do_div(stripe_nr, map->stripe_len); 4542 4543 if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4544 stripe_nr = stripe_nr * map->num_stripes + i; 4545 do_div(stripe_nr, map->sub_stripes); 4546 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4547 stripe_nr = stripe_nr * map->num_stripes + i; 4548 } 4549 bytenr = chunk_start + stripe_nr * map->stripe_len; 4550 WARN_ON(nr >= map->num_stripes); 4551 for (j = 0; j < nr; j++) { 4552 if (buf[j] == bytenr) 4553 break; 4554 } 4555 if (j == nr) { 4556 WARN_ON(nr >= map->num_stripes); 4557 buf[nr++] = bytenr; 4558 } 4559 } 4560 4561 *logical = buf; 4562 *naddrs = nr; 4563 *stripe_len = map->stripe_len; 4564 4565 free_extent_map(em); 4566 return 0; 4567 } 4568 4569 static void *merge_stripe_index_into_bio_private(void *bi_private, 4570 unsigned int stripe_index) 4571 { 4572 /* 4573 * with single, dup, RAID0, RAID1 and RAID10, stripe_index is 4574 * at most 1. 4575 * The alternative solution (instead of stealing bits from the 4576 * pointer) would be to allocate an intermediate structure 4577 * that contains the old private pointer plus the stripe_index. 4578 */ 4579 BUG_ON((((uintptr_t)bi_private) & 3) != 0); 4580 BUG_ON(stripe_index > 3); 4581 return (void *)(((uintptr_t)bi_private) | stripe_index); 4582 } 4583 4584 static struct btrfs_bio *extract_bbio_from_bio_private(void *bi_private) 4585 { 4586 return (struct btrfs_bio *)(((uintptr_t)bi_private) & ~((uintptr_t)3)); 4587 } 4588 4589 static unsigned int extract_stripe_index_from_bio_private(void *bi_private) 4590 { 4591 return (unsigned int)((uintptr_t)bi_private) & 3; 4592 } 4593 4594 static void btrfs_end_bio(struct bio *bio, int err) 4595 { 4596 struct btrfs_bio *bbio = extract_bbio_from_bio_private(bio->bi_private); 4597 int is_orig_bio = 0; 4598 4599 if (err) { 4600 atomic_inc(&bbio->error); 4601 if (err == -EIO || err == -EREMOTEIO) { 4602 unsigned int stripe_index = 4603 extract_stripe_index_from_bio_private( 4604 bio->bi_private); 4605 struct btrfs_device *dev; 4606 4607 BUG_ON(stripe_index >= bbio->num_stripes); 4608 dev = bbio->stripes[stripe_index].dev; 4609 if (dev->bdev) { 4610 if (bio->bi_rw & WRITE) 4611 btrfs_dev_stat_inc(dev, 4612 BTRFS_DEV_STAT_WRITE_ERRS); 4613 else 4614 btrfs_dev_stat_inc(dev, 4615 BTRFS_DEV_STAT_READ_ERRS); 4616 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH) 4617 btrfs_dev_stat_inc(dev, 4618 BTRFS_DEV_STAT_FLUSH_ERRS); 4619 btrfs_dev_stat_print_on_error(dev); 4620 } 4621 } 4622 } 4623 4624 if (bio == bbio->orig_bio) 4625 is_orig_bio = 1; 4626 4627 if (atomic_dec_and_test(&bbio->stripes_pending)) { 4628 if (!is_orig_bio) { 4629 bio_put(bio); 4630 bio = bbio->orig_bio; 4631 } 4632 bio->bi_private = bbio->private; 4633 bio->bi_end_io = bbio->end_io; 4634 bio->bi_bdev = (struct block_device *) 4635 (unsigned long)bbio->mirror_num; 4636 /* only send an error to the higher layers if it is 4637 * beyond the tolerance of the multi-bio 4638 */ 4639 if (atomic_read(&bbio->error) > bbio->max_errors) { 4640 err = -EIO; 4641 } else { 4642 /* 4643 * this bio is actually up to date, we didn't 4644 * go over the max number of errors 4645 */ 4646 set_bit(BIO_UPTODATE, &bio->bi_flags); 4647 err = 0; 4648 } 4649 kfree(bbio); 4650 4651 bio_endio(bio, err); 4652 } else if (!is_orig_bio) { 4653 bio_put(bio); 4654 } 4655 } 4656 4657 struct async_sched { 4658 struct bio *bio; 4659 int rw; 4660 struct btrfs_fs_info *info; 4661 struct btrfs_work work; 4662 }; 4663 4664 /* 4665 * see run_scheduled_bios for a description of why bios are collected for 4666 * async submit. 4667 * 4668 * This will add one bio to the pending list for a device and make sure 4669 * the work struct is scheduled. 4670 */ 4671 static noinline void schedule_bio(struct btrfs_root *root, 4672 struct btrfs_device *device, 4673 int rw, struct bio *bio) 4674 { 4675 int should_queue = 1; 4676 struct btrfs_pending_bios *pending_bios; 4677 4678 /* don't bother with additional async steps for reads, right now */ 4679 if (!(rw & REQ_WRITE)) { 4680 bio_get(bio); 4681 btrfsic_submit_bio(rw, bio); 4682 bio_put(bio); 4683 return; 4684 } 4685 4686 /* 4687 * nr_async_bios allows us to reliably return congestion to the 4688 * higher layers. Otherwise, the async bio makes it appear we have 4689 * made progress against dirty pages when we've really just put it 4690 * on a queue for later 4691 */ 4692 atomic_inc(&root->fs_info->nr_async_bios); 4693 WARN_ON(bio->bi_next); 4694 bio->bi_next = NULL; 4695 bio->bi_rw |= rw; 4696 4697 spin_lock(&device->io_lock); 4698 if (bio->bi_rw & REQ_SYNC) 4699 pending_bios = &device->pending_sync_bios; 4700 else 4701 pending_bios = &device->pending_bios; 4702 4703 if (pending_bios->tail) 4704 pending_bios->tail->bi_next = bio; 4705 4706 pending_bios->tail = bio; 4707 if (!pending_bios->head) 4708 pending_bios->head = bio; 4709 if (device->running_pending) 4710 should_queue = 0; 4711 4712 spin_unlock(&device->io_lock); 4713 4714 if (should_queue) 4715 btrfs_queue_worker(&root->fs_info->submit_workers, 4716 &device->work); 4717 } 4718 4719 static int bio_size_ok(struct block_device *bdev, struct bio *bio, 4720 sector_t sector) 4721 { 4722 struct bio_vec *prev; 4723 struct request_queue *q = bdev_get_queue(bdev); 4724 unsigned short max_sectors = queue_max_sectors(q); 4725 struct bvec_merge_data bvm = { 4726 .bi_bdev = bdev, 4727 .bi_sector = sector, 4728 .bi_rw = bio->bi_rw, 4729 }; 4730 4731 if (bio->bi_vcnt == 0) { 4732 WARN_ON(1); 4733 return 1; 4734 } 4735 4736 prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; 4737 if ((bio->bi_size >> 9) > max_sectors) 4738 return 0; 4739 4740 if (!q->merge_bvec_fn) 4741 return 1; 4742 4743 bvm.bi_size = bio->bi_size - prev->bv_len; 4744 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) 4745 return 0; 4746 return 1; 4747 } 4748 4749 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 4750 struct bio *bio, u64 physical, int dev_nr, 4751 int rw, int async) 4752 { 4753 struct btrfs_device *dev = bbio->stripes[dev_nr].dev; 4754 4755 bio->bi_private = bbio; 4756 bio->bi_private = merge_stripe_index_into_bio_private( 4757 bio->bi_private, (unsigned int)dev_nr); 4758 bio->bi_end_io = btrfs_end_bio; 4759 bio->bi_sector = physical >> 9; 4760 #ifdef DEBUG 4761 { 4762 struct rcu_string *name; 4763 4764 rcu_read_lock(); 4765 name = rcu_dereference(dev->name); 4766 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu " 4767 "(%s id %llu), size=%u\n", rw, 4768 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, 4769 name->str, dev->devid, bio->bi_size); 4770 rcu_read_unlock(); 4771 } 4772 #endif 4773 bio->bi_bdev = dev->bdev; 4774 if (async) 4775 schedule_bio(root, dev, rw, bio); 4776 else 4777 btrfsic_submit_bio(rw, bio); 4778 } 4779 4780 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 4781 struct bio *first_bio, struct btrfs_device *dev, 4782 int dev_nr, int rw, int async) 4783 { 4784 struct bio_vec *bvec = first_bio->bi_io_vec; 4785 struct bio *bio; 4786 int nr_vecs = bio_get_nr_vecs(dev->bdev); 4787 u64 physical = bbio->stripes[dev_nr].physical; 4788 4789 again: 4790 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS); 4791 if (!bio) 4792 return -ENOMEM; 4793 4794 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) { 4795 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len, 4796 bvec->bv_offset) < bvec->bv_len) { 4797 u64 len = bio->bi_size; 4798 4799 atomic_inc(&bbio->stripes_pending); 4800 submit_stripe_bio(root, bbio, bio, physical, dev_nr, 4801 rw, async); 4802 physical += len; 4803 goto again; 4804 } 4805 bvec++; 4806 } 4807 4808 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async); 4809 return 0; 4810 } 4811 4812 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) 4813 { 4814 atomic_inc(&bbio->error); 4815 if (atomic_dec_and_test(&bbio->stripes_pending)) { 4816 bio->bi_private = bbio->private; 4817 bio->bi_end_io = bbio->end_io; 4818 bio->bi_bdev = (struct block_device *) 4819 (unsigned long)bbio->mirror_num; 4820 bio->bi_sector = logical >> 9; 4821 kfree(bbio); 4822 bio_endio(bio, -EIO); 4823 } 4824 } 4825 4826 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, 4827 int mirror_num, int async_submit) 4828 { 4829 struct btrfs_device *dev; 4830 struct bio *first_bio = bio; 4831 u64 logical = (u64)bio->bi_sector << 9; 4832 u64 length = 0; 4833 u64 map_length; 4834 int ret; 4835 int dev_nr = 0; 4836 int total_devs = 1; 4837 struct btrfs_bio *bbio = NULL; 4838 4839 length = bio->bi_size; 4840 map_length = length; 4841 4842 ret = btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio, 4843 mirror_num); 4844 if (ret) 4845 return ret; 4846 4847 total_devs = bbio->num_stripes; 4848 if (map_length < length) { 4849 printk(KERN_CRIT "btrfs: mapping failed logical %llu bio len %llu " 4850 "len %llu\n", (unsigned long long)logical, 4851 (unsigned long long)length, 4852 (unsigned long long)map_length); 4853 BUG(); 4854 } 4855 4856 bbio->orig_bio = first_bio; 4857 bbio->private = first_bio->bi_private; 4858 bbio->end_io = first_bio->bi_end_io; 4859 atomic_set(&bbio->stripes_pending, bbio->num_stripes); 4860 4861 while (dev_nr < total_devs) { 4862 dev = bbio->stripes[dev_nr].dev; 4863 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) { 4864 bbio_error(bbio, first_bio, logical); 4865 dev_nr++; 4866 continue; 4867 } 4868 4869 /* 4870 * Check and see if we're ok with this bio based on it's size 4871 * and offset with the given device. 4872 */ 4873 if (!bio_size_ok(dev->bdev, first_bio, 4874 bbio->stripes[dev_nr].physical >> 9)) { 4875 ret = breakup_stripe_bio(root, bbio, first_bio, dev, 4876 dev_nr, rw, async_submit); 4877 BUG_ON(ret); 4878 dev_nr++; 4879 continue; 4880 } 4881 4882 if (dev_nr < total_devs - 1) { 4883 bio = bio_clone(first_bio, GFP_NOFS); 4884 BUG_ON(!bio); /* -ENOMEM */ 4885 } else { 4886 bio = first_bio; 4887 } 4888 4889 submit_stripe_bio(root, bbio, bio, 4890 bbio->stripes[dev_nr].physical, dev_nr, rw, 4891 async_submit); 4892 dev_nr++; 4893 } 4894 return 0; 4895 } 4896 4897 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, 4898 u8 *uuid, u8 *fsid) 4899 { 4900 struct btrfs_device *device; 4901 struct btrfs_fs_devices *cur_devices; 4902 4903 cur_devices = fs_info->fs_devices; 4904 while (cur_devices) { 4905 if (!fsid || 4906 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 4907 device = __find_device(&cur_devices->devices, 4908 devid, uuid); 4909 if (device) 4910 return device; 4911 } 4912 cur_devices = cur_devices->seed; 4913 } 4914 return NULL; 4915 } 4916 4917 static struct btrfs_device *add_missing_dev(struct btrfs_root *root, 4918 u64 devid, u8 *dev_uuid) 4919 { 4920 struct btrfs_device *device; 4921 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 4922 4923 device = kzalloc(sizeof(*device), GFP_NOFS); 4924 if (!device) 4925 return NULL; 4926 list_add(&device->dev_list, 4927 &fs_devices->devices); 4928 device->dev_root = root->fs_info->dev_root; 4929 device->devid = devid; 4930 device->work.func = pending_bios_fn; 4931 device->fs_devices = fs_devices; 4932 device->missing = 1; 4933 fs_devices->num_devices++; 4934 fs_devices->missing_devices++; 4935 spin_lock_init(&device->io_lock); 4936 INIT_LIST_HEAD(&device->dev_alloc_list); 4937 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE); 4938 return device; 4939 } 4940 4941 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, 4942 struct extent_buffer *leaf, 4943 struct btrfs_chunk *chunk) 4944 { 4945 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 4946 struct map_lookup *map; 4947 struct extent_map *em; 4948 u64 logical; 4949 u64 length; 4950 u64 devid; 4951 u8 uuid[BTRFS_UUID_SIZE]; 4952 int num_stripes; 4953 int ret; 4954 int i; 4955 4956 logical = key->offset; 4957 length = btrfs_chunk_length(leaf, chunk); 4958 4959 read_lock(&map_tree->map_tree.lock); 4960 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1); 4961 read_unlock(&map_tree->map_tree.lock); 4962 4963 /* already mapped? */ 4964 if (em && em->start <= logical && em->start + em->len > logical) { 4965 free_extent_map(em); 4966 return 0; 4967 } else if (em) { 4968 free_extent_map(em); 4969 } 4970 4971 em = alloc_extent_map(); 4972 if (!em) 4973 return -ENOMEM; 4974 num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 4975 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 4976 if (!map) { 4977 free_extent_map(em); 4978 return -ENOMEM; 4979 } 4980 4981 em->bdev = (struct block_device *)map; 4982 em->start = logical; 4983 em->len = length; 4984 em->orig_start = 0; 4985 em->block_start = 0; 4986 em->block_len = em->len; 4987 4988 map->num_stripes = num_stripes; 4989 map->io_width = btrfs_chunk_io_width(leaf, chunk); 4990 map->io_align = btrfs_chunk_io_align(leaf, chunk); 4991 map->sector_size = btrfs_chunk_sector_size(leaf, chunk); 4992 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); 4993 map->type = btrfs_chunk_type(leaf, chunk); 4994 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); 4995 for (i = 0; i < num_stripes; i++) { 4996 map->stripes[i].physical = 4997 btrfs_stripe_offset_nr(leaf, chunk, i); 4998 devid = btrfs_stripe_devid_nr(leaf, chunk, i); 4999 read_extent_buffer(leaf, uuid, (unsigned long) 5000 btrfs_stripe_dev_uuid_nr(chunk, i), 5001 BTRFS_UUID_SIZE); 5002 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid, 5003 uuid, NULL); 5004 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) { 5005 kfree(map); 5006 free_extent_map(em); 5007 return -EIO; 5008 } 5009 if (!map->stripes[i].dev) { 5010 map->stripes[i].dev = 5011 add_missing_dev(root, devid, uuid); 5012 if (!map->stripes[i].dev) { 5013 kfree(map); 5014 free_extent_map(em); 5015 return -EIO; 5016 } 5017 } 5018 map->stripes[i].dev->in_fs_metadata = 1; 5019 } 5020 5021 write_lock(&map_tree->map_tree.lock); 5022 ret = add_extent_mapping(&map_tree->map_tree, em); 5023 write_unlock(&map_tree->map_tree.lock); 5024 BUG_ON(ret); /* Tree corruption */ 5025 free_extent_map(em); 5026 5027 return 0; 5028 } 5029 5030 static void fill_device_from_item(struct extent_buffer *leaf, 5031 struct btrfs_dev_item *dev_item, 5032 struct btrfs_device *device) 5033 { 5034 unsigned long ptr; 5035 5036 device->devid = btrfs_device_id(leaf, dev_item); 5037 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); 5038 device->total_bytes = device->disk_total_bytes; 5039 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); 5040 device->type = btrfs_device_type(leaf, dev_item); 5041 device->io_align = btrfs_device_io_align(leaf, dev_item); 5042 device->io_width = btrfs_device_io_width(leaf, dev_item); 5043 device->sector_size = btrfs_device_sector_size(leaf, dev_item); 5044 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); 5045 device->is_tgtdev_for_dev_replace = 0; 5046 5047 ptr = (unsigned long)btrfs_device_uuid(dev_item); 5048 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 5049 } 5050 5051 static int open_seed_devices(struct btrfs_root *root, u8 *fsid) 5052 { 5053 struct btrfs_fs_devices *fs_devices; 5054 int ret; 5055 5056 BUG_ON(!mutex_is_locked(&uuid_mutex)); 5057 5058 fs_devices = root->fs_info->fs_devices->seed; 5059 while (fs_devices) { 5060 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5061 ret = 0; 5062 goto out; 5063 } 5064 fs_devices = fs_devices->seed; 5065 } 5066 5067 fs_devices = find_fsid(fsid); 5068 if (!fs_devices) { 5069 ret = -ENOENT; 5070 goto out; 5071 } 5072 5073 fs_devices = clone_fs_devices(fs_devices); 5074 if (IS_ERR(fs_devices)) { 5075 ret = PTR_ERR(fs_devices); 5076 goto out; 5077 } 5078 5079 ret = __btrfs_open_devices(fs_devices, FMODE_READ, 5080 root->fs_info->bdev_holder); 5081 if (ret) { 5082 free_fs_devices(fs_devices); 5083 goto out; 5084 } 5085 5086 if (!fs_devices->seeding) { 5087 __btrfs_close_devices(fs_devices); 5088 free_fs_devices(fs_devices); 5089 ret = -EINVAL; 5090 goto out; 5091 } 5092 5093 fs_devices->seed = root->fs_info->fs_devices->seed; 5094 root->fs_info->fs_devices->seed = fs_devices; 5095 out: 5096 return ret; 5097 } 5098 5099 static int read_one_dev(struct btrfs_root *root, 5100 struct extent_buffer *leaf, 5101 struct btrfs_dev_item *dev_item) 5102 { 5103 struct btrfs_device *device; 5104 u64 devid; 5105 int ret; 5106 u8 fs_uuid[BTRFS_UUID_SIZE]; 5107 u8 dev_uuid[BTRFS_UUID_SIZE]; 5108 5109 devid = btrfs_device_id(leaf, dev_item); 5110 read_extent_buffer(leaf, dev_uuid, 5111 (unsigned long)btrfs_device_uuid(dev_item), 5112 BTRFS_UUID_SIZE); 5113 read_extent_buffer(leaf, fs_uuid, 5114 (unsigned long)btrfs_device_fsid(dev_item), 5115 BTRFS_UUID_SIZE); 5116 5117 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) { 5118 ret = open_seed_devices(root, fs_uuid); 5119 if (ret && !btrfs_test_opt(root, DEGRADED)) 5120 return ret; 5121 } 5122 5123 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid); 5124 if (!device || !device->bdev) { 5125 if (!btrfs_test_opt(root, DEGRADED)) 5126 return -EIO; 5127 5128 if (!device) { 5129 printk(KERN_WARNING "warning devid %llu missing\n", 5130 (unsigned long long)devid); 5131 device = add_missing_dev(root, devid, dev_uuid); 5132 if (!device) 5133 return -ENOMEM; 5134 } else if (!device->missing) { 5135 /* 5136 * this happens when a device that was properly setup 5137 * in the device info lists suddenly goes bad. 5138 * device->bdev is NULL, and so we have to set 5139 * device->missing to one here 5140 */ 5141 root->fs_info->fs_devices->missing_devices++; 5142 device->missing = 1; 5143 } 5144 } 5145 5146 if (device->fs_devices != root->fs_info->fs_devices) { 5147 BUG_ON(device->writeable); 5148 if (device->generation != 5149 btrfs_device_generation(leaf, dev_item)) 5150 return -EINVAL; 5151 } 5152 5153 fill_device_from_item(leaf, dev_item, device); 5154 device->dev_root = root->fs_info->dev_root; 5155 device->in_fs_metadata = 1; 5156 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 5157 device->fs_devices->total_rw_bytes += device->total_bytes; 5158 spin_lock(&root->fs_info->free_chunk_lock); 5159 root->fs_info->free_chunk_space += device->total_bytes - 5160 device->bytes_used; 5161 spin_unlock(&root->fs_info->free_chunk_lock); 5162 } 5163 ret = 0; 5164 return ret; 5165 } 5166 5167 int btrfs_read_sys_array(struct btrfs_root *root) 5168 { 5169 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 5170 struct extent_buffer *sb; 5171 struct btrfs_disk_key *disk_key; 5172 struct btrfs_chunk *chunk; 5173 u8 *ptr; 5174 unsigned long sb_ptr; 5175 int ret = 0; 5176 u32 num_stripes; 5177 u32 array_size; 5178 u32 len = 0; 5179 u32 cur; 5180 struct btrfs_key key; 5181 5182 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET, 5183 BTRFS_SUPER_INFO_SIZE); 5184 if (!sb) 5185 return -ENOMEM; 5186 btrfs_set_buffer_uptodate(sb); 5187 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); 5188 /* 5189 * The sb extent buffer is artifical and just used to read the system array. 5190 * btrfs_set_buffer_uptodate() call does not properly mark all it's 5191 * pages up-to-date when the page is larger: extent does not cover the 5192 * whole page and consequently check_page_uptodate does not find all 5193 * the page's extents up-to-date (the hole beyond sb), 5194 * write_extent_buffer then triggers a WARN_ON. 5195 * 5196 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle, 5197 * but sb spans only this function. Add an explicit SetPageUptodate call 5198 * to silence the warning eg. on PowerPC 64. 5199 */ 5200 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE) 5201 SetPageUptodate(sb->pages[0]); 5202 5203 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); 5204 array_size = btrfs_super_sys_array_size(super_copy); 5205 5206 ptr = super_copy->sys_chunk_array; 5207 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array); 5208 cur = 0; 5209 5210 while (cur < array_size) { 5211 disk_key = (struct btrfs_disk_key *)ptr; 5212 btrfs_disk_key_to_cpu(&key, disk_key); 5213 5214 len = sizeof(*disk_key); ptr += len; 5215 sb_ptr += len; 5216 cur += len; 5217 5218 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 5219 chunk = (struct btrfs_chunk *)sb_ptr; 5220 ret = read_one_chunk(root, &key, sb, chunk); 5221 if (ret) 5222 break; 5223 num_stripes = btrfs_chunk_num_stripes(sb, chunk); 5224 len = btrfs_chunk_item_size(num_stripes); 5225 } else { 5226 ret = -EIO; 5227 break; 5228 } 5229 ptr += len; 5230 sb_ptr += len; 5231 cur += len; 5232 } 5233 free_extent_buffer(sb); 5234 return ret; 5235 } 5236 5237 int btrfs_read_chunk_tree(struct btrfs_root *root) 5238 { 5239 struct btrfs_path *path; 5240 struct extent_buffer *leaf; 5241 struct btrfs_key key; 5242 struct btrfs_key found_key; 5243 int ret; 5244 int slot; 5245 5246 root = root->fs_info->chunk_root; 5247 5248 path = btrfs_alloc_path(); 5249 if (!path) 5250 return -ENOMEM; 5251 5252 mutex_lock(&uuid_mutex); 5253 lock_chunks(root); 5254 5255 /* first we search for all of the device items, and then we 5256 * read in all of the chunk items. This way we can create chunk 5257 * mappings that reference all of the devices that are afound 5258 */ 5259 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 5260 key.offset = 0; 5261 key.type = 0; 5262 again: 5263 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5264 if (ret < 0) 5265 goto error; 5266 while (1) { 5267 leaf = path->nodes[0]; 5268 slot = path->slots[0]; 5269 if (slot >= btrfs_header_nritems(leaf)) { 5270 ret = btrfs_next_leaf(root, path); 5271 if (ret == 0) 5272 continue; 5273 if (ret < 0) 5274 goto error; 5275 break; 5276 } 5277 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5278 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5279 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID) 5280 break; 5281 if (found_key.type == BTRFS_DEV_ITEM_KEY) { 5282 struct btrfs_dev_item *dev_item; 5283 dev_item = btrfs_item_ptr(leaf, slot, 5284 struct btrfs_dev_item); 5285 ret = read_one_dev(root, leaf, dev_item); 5286 if (ret) 5287 goto error; 5288 } 5289 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { 5290 struct btrfs_chunk *chunk; 5291 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 5292 ret = read_one_chunk(root, &found_key, leaf, chunk); 5293 if (ret) 5294 goto error; 5295 } 5296 path->slots[0]++; 5297 } 5298 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5299 key.objectid = 0; 5300 btrfs_release_path(path); 5301 goto again; 5302 } 5303 ret = 0; 5304 error: 5305 unlock_chunks(root); 5306 mutex_unlock(&uuid_mutex); 5307 5308 btrfs_free_path(path); 5309 return ret; 5310 } 5311 5312 static void __btrfs_reset_dev_stats(struct btrfs_device *dev) 5313 { 5314 int i; 5315 5316 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5317 btrfs_dev_stat_reset(dev, i); 5318 } 5319 5320 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) 5321 { 5322 struct btrfs_key key; 5323 struct btrfs_key found_key; 5324 struct btrfs_root *dev_root = fs_info->dev_root; 5325 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5326 struct extent_buffer *eb; 5327 int slot; 5328 int ret = 0; 5329 struct btrfs_device *device; 5330 struct btrfs_path *path = NULL; 5331 int i; 5332 5333 path = btrfs_alloc_path(); 5334 if (!path) { 5335 ret = -ENOMEM; 5336 goto out; 5337 } 5338 5339 mutex_lock(&fs_devices->device_list_mutex); 5340 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5341 int item_size; 5342 struct btrfs_dev_stats_item *ptr; 5343 5344 key.objectid = 0; 5345 key.type = BTRFS_DEV_STATS_KEY; 5346 key.offset = device->devid; 5347 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 5348 if (ret) { 5349 __btrfs_reset_dev_stats(device); 5350 device->dev_stats_valid = 1; 5351 btrfs_release_path(path); 5352 continue; 5353 } 5354 slot = path->slots[0]; 5355 eb = path->nodes[0]; 5356 btrfs_item_key_to_cpu(eb, &found_key, slot); 5357 item_size = btrfs_item_size_nr(eb, slot); 5358 5359 ptr = btrfs_item_ptr(eb, slot, 5360 struct btrfs_dev_stats_item); 5361 5362 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5363 if (item_size >= (1 + i) * sizeof(__le64)) 5364 btrfs_dev_stat_set(device, i, 5365 btrfs_dev_stats_value(eb, ptr, i)); 5366 else 5367 btrfs_dev_stat_reset(device, i); 5368 } 5369 5370 device->dev_stats_valid = 1; 5371 btrfs_dev_stat_print_on_load(device); 5372 btrfs_release_path(path); 5373 } 5374 mutex_unlock(&fs_devices->device_list_mutex); 5375 5376 out: 5377 btrfs_free_path(path); 5378 return ret < 0 ? ret : 0; 5379 } 5380 5381 static int update_dev_stat_item(struct btrfs_trans_handle *trans, 5382 struct btrfs_root *dev_root, 5383 struct btrfs_device *device) 5384 { 5385 struct btrfs_path *path; 5386 struct btrfs_key key; 5387 struct extent_buffer *eb; 5388 struct btrfs_dev_stats_item *ptr; 5389 int ret; 5390 int i; 5391 5392 key.objectid = 0; 5393 key.type = BTRFS_DEV_STATS_KEY; 5394 key.offset = device->devid; 5395 5396 path = btrfs_alloc_path(); 5397 BUG_ON(!path); 5398 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 5399 if (ret < 0) { 5400 printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n", 5401 ret, rcu_str_deref(device->name)); 5402 goto out; 5403 } 5404 5405 if (ret == 0 && 5406 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 5407 /* need to delete old one and insert a new one */ 5408 ret = btrfs_del_item(trans, dev_root, path); 5409 if (ret != 0) { 5410 printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n", 5411 rcu_str_deref(device->name), ret); 5412 goto out; 5413 } 5414 ret = 1; 5415 } 5416 5417 if (ret == 1) { 5418 /* need to insert a new item */ 5419 btrfs_release_path(path); 5420 ret = btrfs_insert_empty_item(trans, dev_root, path, 5421 &key, sizeof(*ptr)); 5422 if (ret < 0) { 5423 printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n", 5424 rcu_str_deref(device->name), ret); 5425 goto out; 5426 } 5427 } 5428 5429 eb = path->nodes[0]; 5430 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); 5431 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5432 btrfs_set_dev_stats_value(eb, ptr, i, 5433 btrfs_dev_stat_read(device, i)); 5434 btrfs_mark_buffer_dirty(eb); 5435 5436 out: 5437 btrfs_free_path(path); 5438 return ret; 5439 } 5440 5441 /* 5442 * called from commit_transaction. Writes all changed device stats to disk. 5443 */ 5444 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, 5445 struct btrfs_fs_info *fs_info) 5446 { 5447 struct btrfs_root *dev_root = fs_info->dev_root; 5448 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5449 struct btrfs_device *device; 5450 int ret = 0; 5451 5452 mutex_lock(&fs_devices->device_list_mutex); 5453 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5454 if (!device->dev_stats_valid || !device->dev_stats_dirty) 5455 continue; 5456 5457 ret = update_dev_stat_item(trans, dev_root, device); 5458 if (!ret) 5459 device->dev_stats_dirty = 0; 5460 } 5461 mutex_unlock(&fs_devices->device_list_mutex); 5462 5463 return ret; 5464 } 5465 5466 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) 5467 { 5468 btrfs_dev_stat_inc(dev, index); 5469 btrfs_dev_stat_print_on_error(dev); 5470 } 5471 5472 void btrfs_dev_stat_print_on_error(struct btrfs_device *dev) 5473 { 5474 if (!dev->dev_stats_valid) 5475 return; 5476 printk_ratelimited_in_rcu(KERN_ERR 5477 "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5478 rcu_str_deref(dev->name), 5479 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5480 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5481 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5482 btrfs_dev_stat_read(dev, 5483 BTRFS_DEV_STAT_CORRUPTION_ERRS), 5484 btrfs_dev_stat_read(dev, 5485 BTRFS_DEV_STAT_GENERATION_ERRS)); 5486 } 5487 5488 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) 5489 { 5490 int i; 5491 5492 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5493 if (btrfs_dev_stat_read(dev, i) != 0) 5494 break; 5495 if (i == BTRFS_DEV_STAT_VALUES_MAX) 5496 return; /* all values == 0, suppress message */ 5497 5498 printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5499 rcu_str_deref(dev->name), 5500 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5501 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5502 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5503 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), 5504 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); 5505 } 5506 5507 int btrfs_get_dev_stats(struct btrfs_root *root, 5508 struct btrfs_ioctl_get_dev_stats *stats) 5509 { 5510 struct btrfs_device *dev; 5511 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5512 int i; 5513 5514 mutex_lock(&fs_devices->device_list_mutex); 5515 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL); 5516 mutex_unlock(&fs_devices->device_list_mutex); 5517 5518 if (!dev) { 5519 printk(KERN_WARNING 5520 "btrfs: get dev_stats failed, device not found\n"); 5521 return -ENODEV; 5522 } else if (!dev->dev_stats_valid) { 5523 printk(KERN_WARNING 5524 "btrfs: get dev_stats failed, not yet valid\n"); 5525 return -ENODEV; 5526 } else if (stats->flags & BTRFS_DEV_STATS_RESET) { 5527 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5528 if (stats->nr_items > i) 5529 stats->values[i] = 5530 btrfs_dev_stat_read_and_reset(dev, i); 5531 else 5532 btrfs_dev_stat_reset(dev, i); 5533 } 5534 } else { 5535 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5536 if (stats->nr_items > i) 5537 stats->values[i] = btrfs_dev_stat_read(dev, i); 5538 } 5539 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) 5540 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; 5541 return 0; 5542 } 5543 5544 int btrfs_scratch_superblock(struct btrfs_device *device) 5545 { 5546 struct buffer_head *bh; 5547 struct btrfs_super_block *disk_super; 5548 5549 bh = btrfs_read_dev_super(device->bdev); 5550 if (!bh) 5551 return -EINVAL; 5552 disk_super = (struct btrfs_super_block *)bh->b_data; 5553 5554 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 5555 set_buffer_dirty(bh); 5556 sync_dirty_buffer(bh); 5557 brelse(bh); 5558 5559 return 0; 5560 } 5561