1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 #include <linux/sched.h> 19 #include <linux/bio.h> 20 #include <linux/slab.h> 21 #include <linux/buffer_head.h> 22 #include <linux/blkdev.h> 23 #include <linux/random.h> 24 #include <linux/iocontext.h> 25 #include <linux/capability.h> 26 #include <linux/ratelimit.h> 27 #include <linux/kthread.h> 28 #include <linux/raid/pq.h> 29 #include <asm/div64.h> 30 #include "compat.h" 31 #include "ctree.h" 32 #include "extent_map.h" 33 #include "disk-io.h" 34 #include "transaction.h" 35 #include "print-tree.h" 36 #include "volumes.h" 37 #include "raid56.h" 38 #include "async-thread.h" 39 #include "check-integrity.h" 40 #include "rcu-string.h" 41 #include "math.h" 42 #include "dev-replace.h" 43 44 static int init_first_rw_device(struct btrfs_trans_handle *trans, 45 struct btrfs_root *root, 46 struct btrfs_device *device); 47 static int btrfs_relocate_sys_chunks(struct btrfs_root *root); 48 static void __btrfs_reset_dev_stats(struct btrfs_device *dev); 49 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); 50 51 static DEFINE_MUTEX(uuid_mutex); 52 static LIST_HEAD(fs_uuids); 53 54 static void lock_chunks(struct btrfs_root *root) 55 { 56 mutex_lock(&root->fs_info->chunk_mutex); 57 } 58 59 static void unlock_chunks(struct btrfs_root *root) 60 { 61 mutex_unlock(&root->fs_info->chunk_mutex); 62 } 63 64 static void free_fs_devices(struct btrfs_fs_devices *fs_devices) 65 { 66 struct btrfs_device *device; 67 WARN_ON(fs_devices->opened); 68 while (!list_empty(&fs_devices->devices)) { 69 device = list_entry(fs_devices->devices.next, 70 struct btrfs_device, dev_list); 71 list_del(&device->dev_list); 72 rcu_string_free(device->name); 73 kfree(device); 74 } 75 kfree(fs_devices); 76 } 77 78 static void btrfs_kobject_uevent(struct block_device *bdev, 79 enum kobject_action action) 80 { 81 int ret; 82 83 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 84 if (ret) 85 pr_warn("Sending event '%d' to kobject: '%s' (%p): failed\n", 86 action, 87 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 88 &disk_to_dev(bdev->bd_disk)->kobj); 89 } 90 91 void btrfs_cleanup_fs_uuids(void) 92 { 93 struct btrfs_fs_devices *fs_devices; 94 95 while (!list_empty(&fs_uuids)) { 96 fs_devices = list_entry(fs_uuids.next, 97 struct btrfs_fs_devices, list); 98 list_del(&fs_devices->list); 99 free_fs_devices(fs_devices); 100 } 101 } 102 103 static noinline struct btrfs_device *__find_device(struct list_head *head, 104 u64 devid, u8 *uuid) 105 { 106 struct btrfs_device *dev; 107 108 list_for_each_entry(dev, head, dev_list) { 109 if (dev->devid == devid && 110 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { 111 return dev; 112 } 113 } 114 return NULL; 115 } 116 117 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid) 118 { 119 struct btrfs_fs_devices *fs_devices; 120 121 list_for_each_entry(fs_devices, &fs_uuids, list) { 122 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) 123 return fs_devices; 124 } 125 return NULL; 126 } 127 128 static int 129 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder, 130 int flush, struct block_device **bdev, 131 struct buffer_head **bh) 132 { 133 int ret; 134 135 *bdev = blkdev_get_by_path(device_path, flags, holder); 136 137 if (IS_ERR(*bdev)) { 138 ret = PTR_ERR(*bdev); 139 printk(KERN_INFO "btrfs: open %s failed\n", device_path); 140 goto error; 141 } 142 143 if (flush) 144 filemap_write_and_wait((*bdev)->bd_inode->i_mapping); 145 ret = set_blocksize(*bdev, 4096); 146 if (ret) { 147 blkdev_put(*bdev, flags); 148 goto error; 149 } 150 invalidate_bdev(*bdev); 151 *bh = btrfs_read_dev_super(*bdev); 152 if (!*bh) { 153 ret = -EINVAL; 154 blkdev_put(*bdev, flags); 155 goto error; 156 } 157 158 return 0; 159 160 error: 161 *bdev = NULL; 162 *bh = NULL; 163 return ret; 164 } 165 166 static void requeue_list(struct btrfs_pending_bios *pending_bios, 167 struct bio *head, struct bio *tail) 168 { 169 170 struct bio *old_head; 171 172 old_head = pending_bios->head; 173 pending_bios->head = head; 174 if (pending_bios->tail) 175 tail->bi_next = old_head; 176 else 177 pending_bios->tail = tail; 178 } 179 180 /* 181 * we try to collect pending bios for a device so we don't get a large 182 * number of procs sending bios down to the same device. This greatly 183 * improves the schedulers ability to collect and merge the bios. 184 * 185 * But, it also turns into a long list of bios to process and that is sure 186 * to eventually make the worker thread block. The solution here is to 187 * make some progress and then put this work struct back at the end of 188 * the list if the block device is congested. This way, multiple devices 189 * can make progress from a single worker thread. 190 */ 191 static noinline void run_scheduled_bios(struct btrfs_device *device) 192 { 193 struct bio *pending; 194 struct backing_dev_info *bdi; 195 struct btrfs_fs_info *fs_info; 196 struct btrfs_pending_bios *pending_bios; 197 struct bio *tail; 198 struct bio *cur; 199 int again = 0; 200 unsigned long num_run; 201 unsigned long batch_run = 0; 202 unsigned long limit; 203 unsigned long last_waited = 0; 204 int force_reg = 0; 205 int sync_pending = 0; 206 struct blk_plug plug; 207 208 /* 209 * this function runs all the bios we've collected for 210 * a particular device. We don't want to wander off to 211 * another device without first sending all of these down. 212 * So, setup a plug here and finish it off before we return 213 */ 214 blk_start_plug(&plug); 215 216 bdi = blk_get_backing_dev_info(device->bdev); 217 fs_info = device->dev_root->fs_info; 218 limit = btrfs_async_submit_limit(fs_info); 219 limit = limit * 2 / 3; 220 221 loop: 222 spin_lock(&device->io_lock); 223 224 loop_lock: 225 num_run = 0; 226 227 /* take all the bios off the list at once and process them 228 * later on (without the lock held). But, remember the 229 * tail and other pointers so the bios can be properly reinserted 230 * into the list if we hit congestion 231 */ 232 if (!force_reg && device->pending_sync_bios.head) { 233 pending_bios = &device->pending_sync_bios; 234 force_reg = 1; 235 } else { 236 pending_bios = &device->pending_bios; 237 force_reg = 0; 238 } 239 240 pending = pending_bios->head; 241 tail = pending_bios->tail; 242 WARN_ON(pending && !tail); 243 244 /* 245 * if pending was null this time around, no bios need processing 246 * at all and we can stop. Otherwise it'll loop back up again 247 * and do an additional check so no bios are missed. 248 * 249 * device->running_pending is used to synchronize with the 250 * schedule_bio code. 251 */ 252 if (device->pending_sync_bios.head == NULL && 253 device->pending_bios.head == NULL) { 254 again = 0; 255 device->running_pending = 0; 256 } else { 257 again = 1; 258 device->running_pending = 1; 259 } 260 261 pending_bios->head = NULL; 262 pending_bios->tail = NULL; 263 264 spin_unlock(&device->io_lock); 265 266 while (pending) { 267 268 rmb(); 269 /* we want to work on both lists, but do more bios on the 270 * sync list than the regular list 271 */ 272 if ((num_run > 32 && 273 pending_bios != &device->pending_sync_bios && 274 device->pending_sync_bios.head) || 275 (num_run > 64 && pending_bios == &device->pending_sync_bios && 276 device->pending_bios.head)) { 277 spin_lock(&device->io_lock); 278 requeue_list(pending_bios, pending, tail); 279 goto loop_lock; 280 } 281 282 cur = pending; 283 pending = pending->bi_next; 284 cur->bi_next = NULL; 285 286 if (atomic_dec_return(&fs_info->nr_async_bios) < limit && 287 waitqueue_active(&fs_info->async_submit_wait)) 288 wake_up(&fs_info->async_submit_wait); 289 290 BUG_ON(atomic_read(&cur->bi_cnt) == 0); 291 292 /* 293 * if we're doing the sync list, record that our 294 * plug has some sync requests on it 295 * 296 * If we're doing the regular list and there are 297 * sync requests sitting around, unplug before 298 * we add more 299 */ 300 if (pending_bios == &device->pending_sync_bios) { 301 sync_pending = 1; 302 } else if (sync_pending) { 303 blk_finish_plug(&plug); 304 blk_start_plug(&plug); 305 sync_pending = 0; 306 } 307 308 btrfsic_submit_bio(cur->bi_rw, cur); 309 num_run++; 310 batch_run++; 311 if (need_resched()) 312 cond_resched(); 313 314 /* 315 * we made progress, there is more work to do and the bdi 316 * is now congested. Back off and let other work structs 317 * run instead 318 */ 319 if (pending && bdi_write_congested(bdi) && batch_run > 8 && 320 fs_info->fs_devices->open_devices > 1) { 321 struct io_context *ioc; 322 323 ioc = current->io_context; 324 325 /* 326 * the main goal here is that we don't want to 327 * block if we're going to be able to submit 328 * more requests without blocking. 329 * 330 * This code does two great things, it pokes into 331 * the elevator code from a filesystem _and_ 332 * it makes assumptions about how batching works. 333 */ 334 if (ioc && ioc->nr_batch_requests > 0 && 335 time_before(jiffies, ioc->last_waited + HZ/50UL) && 336 (last_waited == 0 || 337 ioc->last_waited == last_waited)) { 338 /* 339 * we want to go through our batch of 340 * requests and stop. So, we copy out 341 * the ioc->last_waited time and test 342 * against it before looping 343 */ 344 last_waited = ioc->last_waited; 345 if (need_resched()) 346 cond_resched(); 347 continue; 348 } 349 spin_lock(&device->io_lock); 350 requeue_list(pending_bios, pending, tail); 351 device->running_pending = 1; 352 353 spin_unlock(&device->io_lock); 354 btrfs_requeue_work(&device->work); 355 goto done; 356 } 357 /* unplug every 64 requests just for good measure */ 358 if (batch_run % 64 == 0) { 359 blk_finish_plug(&plug); 360 blk_start_plug(&plug); 361 sync_pending = 0; 362 } 363 } 364 365 cond_resched(); 366 if (again) 367 goto loop; 368 369 spin_lock(&device->io_lock); 370 if (device->pending_bios.head || device->pending_sync_bios.head) 371 goto loop_lock; 372 spin_unlock(&device->io_lock); 373 374 done: 375 blk_finish_plug(&plug); 376 } 377 378 static void pending_bios_fn(struct btrfs_work *work) 379 { 380 struct btrfs_device *device; 381 382 device = container_of(work, struct btrfs_device, work); 383 run_scheduled_bios(device); 384 } 385 386 static noinline int device_list_add(const char *path, 387 struct btrfs_super_block *disk_super, 388 u64 devid, struct btrfs_fs_devices **fs_devices_ret) 389 { 390 struct btrfs_device *device; 391 struct btrfs_fs_devices *fs_devices; 392 struct rcu_string *name; 393 u64 found_transid = btrfs_super_generation(disk_super); 394 395 fs_devices = find_fsid(disk_super->fsid); 396 if (!fs_devices) { 397 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 398 if (!fs_devices) 399 return -ENOMEM; 400 INIT_LIST_HEAD(&fs_devices->devices); 401 INIT_LIST_HEAD(&fs_devices->alloc_list); 402 list_add(&fs_devices->list, &fs_uuids); 403 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE); 404 fs_devices->latest_devid = devid; 405 fs_devices->latest_trans = found_transid; 406 mutex_init(&fs_devices->device_list_mutex); 407 device = NULL; 408 } else { 409 device = __find_device(&fs_devices->devices, devid, 410 disk_super->dev_item.uuid); 411 } 412 if (!device) { 413 if (fs_devices->opened) 414 return -EBUSY; 415 416 device = kzalloc(sizeof(*device), GFP_NOFS); 417 if (!device) { 418 /* we can safely leave the fs_devices entry around */ 419 return -ENOMEM; 420 } 421 device->devid = devid; 422 device->dev_stats_valid = 0; 423 device->work.func = pending_bios_fn; 424 memcpy(device->uuid, disk_super->dev_item.uuid, 425 BTRFS_UUID_SIZE); 426 spin_lock_init(&device->io_lock); 427 428 name = rcu_string_strdup(path, GFP_NOFS); 429 if (!name) { 430 kfree(device); 431 return -ENOMEM; 432 } 433 rcu_assign_pointer(device->name, name); 434 INIT_LIST_HEAD(&device->dev_alloc_list); 435 436 /* init readahead state */ 437 spin_lock_init(&device->reada_lock); 438 device->reada_curr_zone = NULL; 439 atomic_set(&device->reada_in_flight, 0); 440 device->reada_next = 0; 441 INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT); 442 INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT); 443 444 mutex_lock(&fs_devices->device_list_mutex); 445 list_add_rcu(&device->dev_list, &fs_devices->devices); 446 mutex_unlock(&fs_devices->device_list_mutex); 447 448 device->fs_devices = fs_devices; 449 fs_devices->num_devices++; 450 } else if (!device->name || strcmp(device->name->str, path)) { 451 name = rcu_string_strdup(path, GFP_NOFS); 452 if (!name) 453 return -ENOMEM; 454 rcu_string_free(device->name); 455 rcu_assign_pointer(device->name, name); 456 if (device->missing) { 457 fs_devices->missing_devices--; 458 device->missing = 0; 459 } 460 } 461 462 if (found_transid > fs_devices->latest_trans) { 463 fs_devices->latest_devid = devid; 464 fs_devices->latest_trans = found_transid; 465 } 466 *fs_devices_ret = fs_devices; 467 return 0; 468 } 469 470 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) 471 { 472 struct btrfs_fs_devices *fs_devices; 473 struct btrfs_device *device; 474 struct btrfs_device *orig_dev; 475 476 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 477 if (!fs_devices) 478 return ERR_PTR(-ENOMEM); 479 480 INIT_LIST_HEAD(&fs_devices->devices); 481 INIT_LIST_HEAD(&fs_devices->alloc_list); 482 INIT_LIST_HEAD(&fs_devices->list); 483 mutex_init(&fs_devices->device_list_mutex); 484 fs_devices->latest_devid = orig->latest_devid; 485 fs_devices->latest_trans = orig->latest_trans; 486 fs_devices->total_devices = orig->total_devices; 487 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid)); 488 489 /* We have held the volume lock, it is safe to get the devices. */ 490 list_for_each_entry(orig_dev, &orig->devices, dev_list) { 491 struct rcu_string *name; 492 493 device = kzalloc(sizeof(*device), GFP_NOFS); 494 if (!device) 495 goto error; 496 497 /* 498 * This is ok to do without rcu read locked because we hold the 499 * uuid mutex so nothing we touch in here is going to disappear. 500 */ 501 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS); 502 if (!name) { 503 kfree(device); 504 goto error; 505 } 506 rcu_assign_pointer(device->name, name); 507 508 device->devid = orig_dev->devid; 509 device->work.func = pending_bios_fn; 510 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid)); 511 spin_lock_init(&device->io_lock); 512 INIT_LIST_HEAD(&device->dev_list); 513 INIT_LIST_HEAD(&device->dev_alloc_list); 514 515 list_add(&device->dev_list, &fs_devices->devices); 516 device->fs_devices = fs_devices; 517 fs_devices->num_devices++; 518 } 519 return fs_devices; 520 error: 521 free_fs_devices(fs_devices); 522 return ERR_PTR(-ENOMEM); 523 } 524 525 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info, 526 struct btrfs_fs_devices *fs_devices, int step) 527 { 528 struct btrfs_device *device, *next; 529 530 struct block_device *latest_bdev = NULL; 531 u64 latest_devid = 0; 532 u64 latest_transid = 0; 533 534 mutex_lock(&uuid_mutex); 535 again: 536 /* This is the initialized path, it is safe to release the devices. */ 537 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 538 if (device->in_fs_metadata) { 539 if (!device->is_tgtdev_for_dev_replace && 540 (!latest_transid || 541 device->generation > latest_transid)) { 542 latest_devid = device->devid; 543 latest_transid = device->generation; 544 latest_bdev = device->bdev; 545 } 546 continue; 547 } 548 549 if (device->devid == BTRFS_DEV_REPLACE_DEVID) { 550 /* 551 * In the first step, keep the device which has 552 * the correct fsid and the devid that is used 553 * for the dev_replace procedure. 554 * In the second step, the dev_replace state is 555 * read from the device tree and it is known 556 * whether the procedure is really active or 557 * not, which means whether this device is 558 * used or whether it should be removed. 559 */ 560 if (step == 0 || device->is_tgtdev_for_dev_replace) { 561 continue; 562 } 563 } 564 if (device->bdev) { 565 blkdev_put(device->bdev, device->mode); 566 device->bdev = NULL; 567 fs_devices->open_devices--; 568 } 569 if (device->writeable) { 570 list_del_init(&device->dev_alloc_list); 571 device->writeable = 0; 572 if (!device->is_tgtdev_for_dev_replace) 573 fs_devices->rw_devices--; 574 } 575 list_del_init(&device->dev_list); 576 fs_devices->num_devices--; 577 rcu_string_free(device->name); 578 kfree(device); 579 } 580 581 if (fs_devices->seed) { 582 fs_devices = fs_devices->seed; 583 goto again; 584 } 585 586 fs_devices->latest_bdev = latest_bdev; 587 fs_devices->latest_devid = latest_devid; 588 fs_devices->latest_trans = latest_transid; 589 590 mutex_unlock(&uuid_mutex); 591 } 592 593 static void __free_device(struct work_struct *work) 594 { 595 struct btrfs_device *device; 596 597 device = container_of(work, struct btrfs_device, rcu_work); 598 599 if (device->bdev) 600 blkdev_put(device->bdev, device->mode); 601 602 rcu_string_free(device->name); 603 kfree(device); 604 } 605 606 static void free_device(struct rcu_head *head) 607 { 608 struct btrfs_device *device; 609 610 device = container_of(head, struct btrfs_device, rcu); 611 612 INIT_WORK(&device->rcu_work, __free_device); 613 schedule_work(&device->rcu_work); 614 } 615 616 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 617 { 618 struct btrfs_device *device; 619 620 if (--fs_devices->opened > 0) 621 return 0; 622 623 mutex_lock(&fs_devices->device_list_mutex); 624 list_for_each_entry(device, &fs_devices->devices, dev_list) { 625 struct btrfs_device *new_device; 626 struct rcu_string *name; 627 628 if (device->bdev) 629 fs_devices->open_devices--; 630 631 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 632 list_del_init(&device->dev_alloc_list); 633 fs_devices->rw_devices--; 634 } 635 636 if (device->can_discard) 637 fs_devices->num_can_discard--; 638 639 new_device = kmalloc(sizeof(*new_device), GFP_NOFS); 640 BUG_ON(!new_device); /* -ENOMEM */ 641 memcpy(new_device, device, sizeof(*new_device)); 642 643 /* Safe because we are under uuid_mutex */ 644 if (device->name) { 645 name = rcu_string_strdup(device->name->str, GFP_NOFS); 646 BUG_ON(device->name && !name); /* -ENOMEM */ 647 rcu_assign_pointer(new_device->name, name); 648 } 649 new_device->bdev = NULL; 650 new_device->writeable = 0; 651 new_device->in_fs_metadata = 0; 652 new_device->can_discard = 0; 653 spin_lock_init(&new_device->io_lock); 654 list_replace_rcu(&device->dev_list, &new_device->dev_list); 655 656 call_rcu(&device->rcu, free_device); 657 } 658 mutex_unlock(&fs_devices->device_list_mutex); 659 660 WARN_ON(fs_devices->open_devices); 661 WARN_ON(fs_devices->rw_devices); 662 fs_devices->opened = 0; 663 fs_devices->seeding = 0; 664 665 return 0; 666 } 667 668 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 669 { 670 struct btrfs_fs_devices *seed_devices = NULL; 671 int ret; 672 673 mutex_lock(&uuid_mutex); 674 ret = __btrfs_close_devices(fs_devices); 675 if (!fs_devices->opened) { 676 seed_devices = fs_devices->seed; 677 fs_devices->seed = NULL; 678 } 679 mutex_unlock(&uuid_mutex); 680 681 while (seed_devices) { 682 fs_devices = seed_devices; 683 seed_devices = fs_devices->seed; 684 __btrfs_close_devices(fs_devices); 685 free_fs_devices(fs_devices); 686 } 687 return ret; 688 } 689 690 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 691 fmode_t flags, void *holder) 692 { 693 struct request_queue *q; 694 struct block_device *bdev; 695 struct list_head *head = &fs_devices->devices; 696 struct btrfs_device *device; 697 struct block_device *latest_bdev = NULL; 698 struct buffer_head *bh; 699 struct btrfs_super_block *disk_super; 700 u64 latest_devid = 0; 701 u64 latest_transid = 0; 702 u64 devid; 703 int seeding = 1; 704 int ret = 0; 705 706 flags |= FMODE_EXCL; 707 708 list_for_each_entry(device, head, dev_list) { 709 if (device->bdev) 710 continue; 711 if (!device->name) 712 continue; 713 714 ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, 715 &bdev, &bh); 716 if (ret) 717 continue; 718 719 disk_super = (struct btrfs_super_block *)bh->b_data; 720 devid = btrfs_stack_device_id(&disk_super->dev_item); 721 if (devid != device->devid) 722 goto error_brelse; 723 724 if (memcmp(device->uuid, disk_super->dev_item.uuid, 725 BTRFS_UUID_SIZE)) 726 goto error_brelse; 727 728 device->generation = btrfs_super_generation(disk_super); 729 if (!latest_transid || device->generation > latest_transid) { 730 latest_devid = devid; 731 latest_transid = device->generation; 732 latest_bdev = bdev; 733 } 734 735 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { 736 device->writeable = 0; 737 } else { 738 device->writeable = !bdev_read_only(bdev); 739 seeding = 0; 740 } 741 742 q = bdev_get_queue(bdev); 743 if (blk_queue_discard(q)) { 744 device->can_discard = 1; 745 fs_devices->num_can_discard++; 746 } 747 748 device->bdev = bdev; 749 device->in_fs_metadata = 0; 750 device->mode = flags; 751 752 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 753 fs_devices->rotating = 1; 754 755 fs_devices->open_devices++; 756 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 757 fs_devices->rw_devices++; 758 list_add(&device->dev_alloc_list, 759 &fs_devices->alloc_list); 760 } 761 brelse(bh); 762 continue; 763 764 error_brelse: 765 brelse(bh); 766 blkdev_put(bdev, flags); 767 continue; 768 } 769 if (fs_devices->open_devices == 0) { 770 ret = -EINVAL; 771 goto out; 772 } 773 fs_devices->seeding = seeding; 774 fs_devices->opened = 1; 775 fs_devices->latest_bdev = latest_bdev; 776 fs_devices->latest_devid = latest_devid; 777 fs_devices->latest_trans = latest_transid; 778 fs_devices->total_rw_bytes = 0; 779 out: 780 return ret; 781 } 782 783 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 784 fmode_t flags, void *holder) 785 { 786 int ret; 787 788 mutex_lock(&uuid_mutex); 789 if (fs_devices->opened) { 790 fs_devices->opened++; 791 ret = 0; 792 } else { 793 ret = __btrfs_open_devices(fs_devices, flags, holder); 794 } 795 mutex_unlock(&uuid_mutex); 796 return ret; 797 } 798 799 /* 800 * Look for a btrfs signature on a device. This may be called out of the mount path 801 * and we are not allowed to call set_blocksize during the scan. The superblock 802 * is read via pagecache 803 */ 804 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, 805 struct btrfs_fs_devices **fs_devices_ret) 806 { 807 struct btrfs_super_block *disk_super; 808 struct block_device *bdev; 809 struct page *page; 810 void *p; 811 int ret = -EINVAL; 812 u64 devid; 813 u64 transid; 814 u64 total_devices; 815 u64 bytenr; 816 pgoff_t index; 817 818 /* 819 * we would like to check all the supers, but that would make 820 * a btrfs mount succeed after a mkfs from a different FS. 821 * So, we need to add a special mount option to scan for 822 * later supers, using BTRFS_SUPER_MIRROR_MAX instead 823 */ 824 bytenr = btrfs_sb_offset(0); 825 flags |= FMODE_EXCL; 826 mutex_lock(&uuid_mutex); 827 828 bdev = blkdev_get_by_path(path, flags, holder); 829 830 if (IS_ERR(bdev)) { 831 ret = PTR_ERR(bdev); 832 goto error; 833 } 834 835 /* make sure our super fits in the device */ 836 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode)) 837 goto error_bdev_put; 838 839 /* make sure our super fits in the page */ 840 if (sizeof(*disk_super) > PAGE_CACHE_SIZE) 841 goto error_bdev_put; 842 843 /* make sure our super doesn't straddle pages on disk */ 844 index = bytenr >> PAGE_CACHE_SHIFT; 845 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index) 846 goto error_bdev_put; 847 848 /* pull in the page with our super */ 849 page = read_cache_page_gfp(bdev->bd_inode->i_mapping, 850 index, GFP_NOFS); 851 852 if (IS_ERR_OR_NULL(page)) 853 goto error_bdev_put; 854 855 p = kmap(page); 856 857 /* align our pointer to the offset of the super block */ 858 disk_super = p + (bytenr & ~PAGE_CACHE_MASK); 859 860 if (btrfs_super_bytenr(disk_super) != bytenr || 861 disk_super->magic != cpu_to_le64(BTRFS_MAGIC)) 862 goto error_unmap; 863 864 devid = btrfs_stack_device_id(&disk_super->dev_item); 865 transid = btrfs_super_generation(disk_super); 866 total_devices = btrfs_super_num_devices(disk_super); 867 868 if (disk_super->label[0]) { 869 if (disk_super->label[BTRFS_LABEL_SIZE - 1]) 870 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0'; 871 printk(KERN_INFO "device label %s ", disk_super->label); 872 } else { 873 printk(KERN_INFO "device fsid %pU ", disk_super->fsid); 874 } 875 876 printk(KERN_CONT "devid %llu transid %llu %s\n", 877 (unsigned long long)devid, (unsigned long long)transid, path); 878 879 ret = device_list_add(path, disk_super, devid, fs_devices_ret); 880 if (!ret && fs_devices_ret) 881 (*fs_devices_ret)->total_devices = total_devices; 882 883 error_unmap: 884 kunmap(page); 885 page_cache_release(page); 886 887 error_bdev_put: 888 blkdev_put(bdev, flags); 889 error: 890 mutex_unlock(&uuid_mutex); 891 return ret; 892 } 893 894 /* helper to account the used device space in the range */ 895 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, 896 u64 end, u64 *length) 897 { 898 struct btrfs_key key; 899 struct btrfs_root *root = device->dev_root; 900 struct btrfs_dev_extent *dev_extent; 901 struct btrfs_path *path; 902 u64 extent_end; 903 int ret; 904 int slot; 905 struct extent_buffer *l; 906 907 *length = 0; 908 909 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace) 910 return 0; 911 912 path = btrfs_alloc_path(); 913 if (!path) 914 return -ENOMEM; 915 path->reada = 2; 916 917 key.objectid = device->devid; 918 key.offset = start; 919 key.type = BTRFS_DEV_EXTENT_KEY; 920 921 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 922 if (ret < 0) 923 goto out; 924 if (ret > 0) { 925 ret = btrfs_previous_item(root, path, key.objectid, key.type); 926 if (ret < 0) 927 goto out; 928 } 929 930 while (1) { 931 l = path->nodes[0]; 932 slot = path->slots[0]; 933 if (slot >= btrfs_header_nritems(l)) { 934 ret = btrfs_next_leaf(root, path); 935 if (ret == 0) 936 continue; 937 if (ret < 0) 938 goto out; 939 940 break; 941 } 942 btrfs_item_key_to_cpu(l, &key, slot); 943 944 if (key.objectid < device->devid) 945 goto next; 946 947 if (key.objectid > device->devid) 948 break; 949 950 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 951 goto next; 952 953 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 954 extent_end = key.offset + btrfs_dev_extent_length(l, 955 dev_extent); 956 if (key.offset <= start && extent_end > end) { 957 *length = end - start + 1; 958 break; 959 } else if (key.offset <= start && extent_end > start) 960 *length += extent_end - start; 961 else if (key.offset > start && extent_end <= end) 962 *length += extent_end - key.offset; 963 else if (key.offset > start && key.offset <= end) { 964 *length += end - key.offset + 1; 965 break; 966 } else if (key.offset > end) 967 break; 968 969 next: 970 path->slots[0]++; 971 } 972 ret = 0; 973 out: 974 btrfs_free_path(path); 975 return ret; 976 } 977 978 /* 979 * find_free_dev_extent - find free space in the specified device 980 * @device: the device which we search the free space in 981 * @num_bytes: the size of the free space that we need 982 * @start: store the start of the free space. 983 * @len: the size of the free space. that we find, or the size of the max 984 * free space if we don't find suitable free space 985 * 986 * this uses a pretty simple search, the expectation is that it is 987 * called very infrequently and that a given device has a small number 988 * of extents 989 * 990 * @start is used to store the start of the free space if we find. But if we 991 * don't find suitable free space, it will be used to store the start position 992 * of the max free space. 993 * 994 * @len is used to store the size of the free space that we find. 995 * But if we don't find suitable free space, it is used to store the size of 996 * the max free space. 997 */ 998 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes, 999 u64 *start, u64 *len) 1000 { 1001 struct btrfs_key key; 1002 struct btrfs_root *root = device->dev_root; 1003 struct btrfs_dev_extent *dev_extent; 1004 struct btrfs_path *path; 1005 u64 hole_size; 1006 u64 max_hole_start; 1007 u64 max_hole_size; 1008 u64 extent_end; 1009 u64 search_start; 1010 u64 search_end = device->total_bytes; 1011 int ret; 1012 int slot; 1013 struct extent_buffer *l; 1014 1015 /* FIXME use last free of some kind */ 1016 1017 /* we don't want to overwrite the superblock on the drive, 1018 * so we make sure to start at an offset of at least 1MB 1019 */ 1020 search_start = max(root->fs_info->alloc_start, 1024ull * 1024); 1021 1022 max_hole_start = search_start; 1023 max_hole_size = 0; 1024 hole_size = 0; 1025 1026 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) { 1027 ret = -ENOSPC; 1028 goto error; 1029 } 1030 1031 path = btrfs_alloc_path(); 1032 if (!path) { 1033 ret = -ENOMEM; 1034 goto error; 1035 } 1036 path->reada = 2; 1037 1038 key.objectid = device->devid; 1039 key.offset = search_start; 1040 key.type = BTRFS_DEV_EXTENT_KEY; 1041 1042 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1043 if (ret < 0) 1044 goto out; 1045 if (ret > 0) { 1046 ret = btrfs_previous_item(root, path, key.objectid, key.type); 1047 if (ret < 0) 1048 goto out; 1049 } 1050 1051 while (1) { 1052 l = path->nodes[0]; 1053 slot = path->slots[0]; 1054 if (slot >= btrfs_header_nritems(l)) { 1055 ret = btrfs_next_leaf(root, path); 1056 if (ret == 0) 1057 continue; 1058 if (ret < 0) 1059 goto out; 1060 1061 break; 1062 } 1063 btrfs_item_key_to_cpu(l, &key, slot); 1064 1065 if (key.objectid < device->devid) 1066 goto next; 1067 1068 if (key.objectid > device->devid) 1069 break; 1070 1071 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 1072 goto next; 1073 1074 if (key.offset > search_start) { 1075 hole_size = key.offset - search_start; 1076 1077 if (hole_size > max_hole_size) { 1078 max_hole_start = search_start; 1079 max_hole_size = hole_size; 1080 } 1081 1082 /* 1083 * If this free space is greater than which we need, 1084 * it must be the max free space that we have found 1085 * until now, so max_hole_start must point to the start 1086 * of this free space and the length of this free space 1087 * is stored in max_hole_size. Thus, we return 1088 * max_hole_start and max_hole_size and go back to the 1089 * caller. 1090 */ 1091 if (hole_size >= num_bytes) { 1092 ret = 0; 1093 goto out; 1094 } 1095 } 1096 1097 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 1098 extent_end = key.offset + btrfs_dev_extent_length(l, 1099 dev_extent); 1100 if (extent_end > search_start) 1101 search_start = extent_end; 1102 next: 1103 path->slots[0]++; 1104 cond_resched(); 1105 } 1106 1107 /* 1108 * At this point, search_start should be the end of 1109 * allocated dev extents, and when shrinking the device, 1110 * search_end may be smaller than search_start. 1111 */ 1112 if (search_end > search_start) 1113 hole_size = search_end - search_start; 1114 1115 if (hole_size > max_hole_size) { 1116 max_hole_start = search_start; 1117 max_hole_size = hole_size; 1118 } 1119 1120 /* See above. */ 1121 if (hole_size < num_bytes) 1122 ret = -ENOSPC; 1123 else 1124 ret = 0; 1125 1126 out: 1127 btrfs_free_path(path); 1128 error: 1129 *start = max_hole_start; 1130 if (len) 1131 *len = max_hole_size; 1132 return ret; 1133 } 1134 1135 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, 1136 struct btrfs_device *device, 1137 u64 start) 1138 { 1139 int ret; 1140 struct btrfs_path *path; 1141 struct btrfs_root *root = device->dev_root; 1142 struct btrfs_key key; 1143 struct btrfs_key found_key; 1144 struct extent_buffer *leaf = NULL; 1145 struct btrfs_dev_extent *extent = NULL; 1146 1147 path = btrfs_alloc_path(); 1148 if (!path) 1149 return -ENOMEM; 1150 1151 key.objectid = device->devid; 1152 key.offset = start; 1153 key.type = BTRFS_DEV_EXTENT_KEY; 1154 again: 1155 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1156 if (ret > 0) { 1157 ret = btrfs_previous_item(root, path, key.objectid, 1158 BTRFS_DEV_EXTENT_KEY); 1159 if (ret) 1160 goto out; 1161 leaf = path->nodes[0]; 1162 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1163 extent = btrfs_item_ptr(leaf, path->slots[0], 1164 struct btrfs_dev_extent); 1165 BUG_ON(found_key.offset > start || found_key.offset + 1166 btrfs_dev_extent_length(leaf, extent) < start); 1167 key = found_key; 1168 btrfs_release_path(path); 1169 goto again; 1170 } else if (ret == 0) { 1171 leaf = path->nodes[0]; 1172 extent = btrfs_item_ptr(leaf, path->slots[0], 1173 struct btrfs_dev_extent); 1174 } else { 1175 btrfs_error(root->fs_info, ret, "Slot search failed"); 1176 goto out; 1177 } 1178 1179 if (device->bytes_used > 0) { 1180 u64 len = btrfs_dev_extent_length(leaf, extent); 1181 device->bytes_used -= len; 1182 spin_lock(&root->fs_info->free_chunk_lock); 1183 root->fs_info->free_chunk_space += len; 1184 spin_unlock(&root->fs_info->free_chunk_lock); 1185 } 1186 ret = btrfs_del_item(trans, root, path); 1187 if (ret) { 1188 btrfs_error(root->fs_info, ret, 1189 "Failed to remove dev extent item"); 1190 } 1191 out: 1192 btrfs_free_path(path); 1193 return ret; 1194 } 1195 1196 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, 1197 struct btrfs_device *device, 1198 u64 chunk_tree, u64 chunk_objectid, 1199 u64 chunk_offset, u64 start, u64 num_bytes) 1200 { 1201 int ret; 1202 struct btrfs_path *path; 1203 struct btrfs_root *root = device->dev_root; 1204 struct btrfs_dev_extent *extent; 1205 struct extent_buffer *leaf; 1206 struct btrfs_key key; 1207 1208 WARN_ON(!device->in_fs_metadata); 1209 WARN_ON(device->is_tgtdev_for_dev_replace); 1210 path = btrfs_alloc_path(); 1211 if (!path) 1212 return -ENOMEM; 1213 1214 key.objectid = device->devid; 1215 key.offset = start; 1216 key.type = BTRFS_DEV_EXTENT_KEY; 1217 ret = btrfs_insert_empty_item(trans, root, path, &key, 1218 sizeof(*extent)); 1219 if (ret) 1220 goto out; 1221 1222 leaf = path->nodes[0]; 1223 extent = btrfs_item_ptr(leaf, path->slots[0], 1224 struct btrfs_dev_extent); 1225 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree); 1226 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid); 1227 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); 1228 1229 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 1230 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent), 1231 BTRFS_UUID_SIZE); 1232 1233 btrfs_set_dev_extent_length(leaf, extent, num_bytes); 1234 btrfs_mark_buffer_dirty(leaf); 1235 out: 1236 btrfs_free_path(path); 1237 return ret; 1238 } 1239 1240 static noinline int find_next_chunk(struct btrfs_root *root, 1241 u64 objectid, u64 *offset) 1242 { 1243 struct btrfs_path *path; 1244 int ret; 1245 struct btrfs_key key; 1246 struct btrfs_chunk *chunk; 1247 struct btrfs_key found_key; 1248 1249 path = btrfs_alloc_path(); 1250 if (!path) 1251 return -ENOMEM; 1252 1253 key.objectid = objectid; 1254 key.offset = (u64)-1; 1255 key.type = BTRFS_CHUNK_ITEM_KEY; 1256 1257 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1258 if (ret < 0) 1259 goto error; 1260 1261 BUG_ON(ret == 0); /* Corruption */ 1262 1263 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY); 1264 if (ret) { 1265 *offset = 0; 1266 } else { 1267 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1268 path->slots[0]); 1269 if (found_key.objectid != objectid) 1270 *offset = 0; 1271 else { 1272 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], 1273 struct btrfs_chunk); 1274 *offset = found_key.offset + 1275 btrfs_chunk_length(path->nodes[0], chunk); 1276 } 1277 } 1278 ret = 0; 1279 error: 1280 btrfs_free_path(path); 1281 return ret; 1282 } 1283 1284 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid) 1285 { 1286 int ret; 1287 struct btrfs_key key; 1288 struct btrfs_key found_key; 1289 struct btrfs_path *path; 1290 1291 root = root->fs_info->chunk_root; 1292 1293 path = btrfs_alloc_path(); 1294 if (!path) 1295 return -ENOMEM; 1296 1297 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1298 key.type = BTRFS_DEV_ITEM_KEY; 1299 key.offset = (u64)-1; 1300 1301 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1302 if (ret < 0) 1303 goto error; 1304 1305 BUG_ON(ret == 0); /* Corruption */ 1306 1307 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID, 1308 BTRFS_DEV_ITEM_KEY); 1309 if (ret) { 1310 *objectid = 1; 1311 } else { 1312 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1313 path->slots[0]); 1314 *objectid = found_key.offset + 1; 1315 } 1316 ret = 0; 1317 error: 1318 btrfs_free_path(path); 1319 return ret; 1320 } 1321 1322 /* 1323 * the device information is stored in the chunk root 1324 * the btrfs_device struct should be fully filled in 1325 */ 1326 int btrfs_add_device(struct btrfs_trans_handle *trans, 1327 struct btrfs_root *root, 1328 struct btrfs_device *device) 1329 { 1330 int ret; 1331 struct btrfs_path *path; 1332 struct btrfs_dev_item *dev_item; 1333 struct extent_buffer *leaf; 1334 struct btrfs_key key; 1335 unsigned long ptr; 1336 1337 root = root->fs_info->chunk_root; 1338 1339 path = btrfs_alloc_path(); 1340 if (!path) 1341 return -ENOMEM; 1342 1343 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1344 key.type = BTRFS_DEV_ITEM_KEY; 1345 key.offset = device->devid; 1346 1347 ret = btrfs_insert_empty_item(trans, root, path, &key, 1348 sizeof(*dev_item)); 1349 if (ret) 1350 goto out; 1351 1352 leaf = path->nodes[0]; 1353 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 1354 1355 btrfs_set_device_id(leaf, dev_item, device->devid); 1356 btrfs_set_device_generation(leaf, dev_item, 0); 1357 btrfs_set_device_type(leaf, dev_item, device->type); 1358 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 1359 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 1360 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 1361 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); 1362 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 1363 btrfs_set_device_group(leaf, dev_item, 0); 1364 btrfs_set_device_seek_speed(leaf, dev_item, 0); 1365 btrfs_set_device_bandwidth(leaf, dev_item, 0); 1366 btrfs_set_device_start_offset(leaf, dev_item, 0); 1367 1368 ptr = (unsigned long)btrfs_device_uuid(dev_item); 1369 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 1370 ptr = (unsigned long)btrfs_device_fsid(dev_item); 1371 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE); 1372 btrfs_mark_buffer_dirty(leaf); 1373 1374 ret = 0; 1375 out: 1376 btrfs_free_path(path); 1377 return ret; 1378 } 1379 1380 static int btrfs_rm_dev_item(struct btrfs_root *root, 1381 struct btrfs_device *device) 1382 { 1383 int ret; 1384 struct btrfs_path *path; 1385 struct btrfs_key key; 1386 struct btrfs_trans_handle *trans; 1387 1388 root = root->fs_info->chunk_root; 1389 1390 path = btrfs_alloc_path(); 1391 if (!path) 1392 return -ENOMEM; 1393 1394 trans = btrfs_start_transaction(root, 0); 1395 if (IS_ERR(trans)) { 1396 btrfs_free_path(path); 1397 return PTR_ERR(trans); 1398 } 1399 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1400 key.type = BTRFS_DEV_ITEM_KEY; 1401 key.offset = device->devid; 1402 lock_chunks(root); 1403 1404 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1405 if (ret < 0) 1406 goto out; 1407 1408 if (ret > 0) { 1409 ret = -ENOENT; 1410 goto out; 1411 } 1412 1413 ret = btrfs_del_item(trans, root, path); 1414 if (ret) 1415 goto out; 1416 out: 1417 btrfs_free_path(path); 1418 unlock_chunks(root); 1419 btrfs_commit_transaction(trans, root); 1420 return ret; 1421 } 1422 1423 int btrfs_rm_device(struct btrfs_root *root, char *device_path) 1424 { 1425 struct btrfs_device *device; 1426 struct btrfs_device *next_device; 1427 struct block_device *bdev; 1428 struct buffer_head *bh = NULL; 1429 struct btrfs_super_block *disk_super; 1430 struct btrfs_fs_devices *cur_devices; 1431 u64 all_avail; 1432 u64 devid; 1433 u64 num_devices; 1434 u8 *dev_uuid; 1435 unsigned seq; 1436 int ret = 0; 1437 bool clear_super = false; 1438 1439 mutex_lock(&uuid_mutex); 1440 1441 do { 1442 seq = read_seqbegin(&root->fs_info->profiles_lock); 1443 1444 all_avail = root->fs_info->avail_data_alloc_bits | 1445 root->fs_info->avail_system_alloc_bits | 1446 root->fs_info->avail_metadata_alloc_bits; 1447 } while (read_seqretry(&root->fs_info->profiles_lock, seq)); 1448 1449 num_devices = root->fs_info->fs_devices->num_devices; 1450 btrfs_dev_replace_lock(&root->fs_info->dev_replace); 1451 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) { 1452 WARN_ON(num_devices < 1); 1453 num_devices--; 1454 } 1455 btrfs_dev_replace_unlock(&root->fs_info->dev_replace); 1456 1457 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) { 1458 printk(KERN_ERR "btrfs: unable to go below four devices " 1459 "on raid10\n"); 1460 ret = -EINVAL; 1461 goto out; 1462 } 1463 1464 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) { 1465 printk(KERN_ERR "btrfs: unable to go below two " 1466 "devices on raid1\n"); 1467 ret = -EINVAL; 1468 goto out; 1469 } 1470 1471 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) && 1472 root->fs_info->fs_devices->rw_devices <= 2) { 1473 printk(KERN_ERR "btrfs: unable to go below two " 1474 "devices on raid5\n"); 1475 ret = -EINVAL; 1476 goto out; 1477 } 1478 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) && 1479 root->fs_info->fs_devices->rw_devices <= 3) { 1480 printk(KERN_ERR "btrfs: unable to go below three " 1481 "devices on raid6\n"); 1482 ret = -EINVAL; 1483 goto out; 1484 } 1485 1486 if (strcmp(device_path, "missing") == 0) { 1487 struct list_head *devices; 1488 struct btrfs_device *tmp; 1489 1490 device = NULL; 1491 devices = &root->fs_info->fs_devices->devices; 1492 /* 1493 * It is safe to read the devices since the volume_mutex 1494 * is held. 1495 */ 1496 list_for_each_entry(tmp, devices, dev_list) { 1497 if (tmp->in_fs_metadata && 1498 !tmp->is_tgtdev_for_dev_replace && 1499 !tmp->bdev) { 1500 device = tmp; 1501 break; 1502 } 1503 } 1504 bdev = NULL; 1505 bh = NULL; 1506 disk_super = NULL; 1507 if (!device) { 1508 printk(KERN_ERR "btrfs: no missing devices found to " 1509 "remove\n"); 1510 goto out; 1511 } 1512 } else { 1513 ret = btrfs_get_bdev_and_sb(device_path, 1514 FMODE_WRITE | FMODE_EXCL, 1515 root->fs_info->bdev_holder, 0, 1516 &bdev, &bh); 1517 if (ret) 1518 goto out; 1519 disk_super = (struct btrfs_super_block *)bh->b_data; 1520 devid = btrfs_stack_device_id(&disk_super->dev_item); 1521 dev_uuid = disk_super->dev_item.uuid; 1522 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1523 disk_super->fsid); 1524 if (!device) { 1525 ret = -ENOENT; 1526 goto error_brelse; 1527 } 1528 } 1529 1530 if (device->is_tgtdev_for_dev_replace) { 1531 pr_err("btrfs: unable to remove the dev_replace target dev\n"); 1532 ret = -EINVAL; 1533 goto error_brelse; 1534 } 1535 1536 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) { 1537 printk(KERN_ERR "btrfs: unable to remove the only writeable " 1538 "device\n"); 1539 ret = -EINVAL; 1540 goto error_brelse; 1541 } 1542 1543 if (device->writeable) { 1544 lock_chunks(root); 1545 list_del_init(&device->dev_alloc_list); 1546 unlock_chunks(root); 1547 root->fs_info->fs_devices->rw_devices--; 1548 clear_super = true; 1549 } 1550 1551 ret = btrfs_shrink_device(device, 0); 1552 if (ret) 1553 goto error_undo; 1554 1555 /* 1556 * TODO: the superblock still includes this device in its num_devices 1557 * counter although write_all_supers() is not locked out. This 1558 * could give a filesystem state which requires a degraded mount. 1559 */ 1560 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); 1561 if (ret) 1562 goto error_undo; 1563 1564 spin_lock(&root->fs_info->free_chunk_lock); 1565 root->fs_info->free_chunk_space = device->total_bytes - 1566 device->bytes_used; 1567 spin_unlock(&root->fs_info->free_chunk_lock); 1568 1569 device->in_fs_metadata = 0; 1570 btrfs_scrub_cancel_dev(root->fs_info, device); 1571 1572 /* 1573 * the device list mutex makes sure that we don't change 1574 * the device list while someone else is writing out all 1575 * the device supers. 1576 */ 1577 1578 cur_devices = device->fs_devices; 1579 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1580 list_del_rcu(&device->dev_list); 1581 1582 device->fs_devices->num_devices--; 1583 device->fs_devices->total_devices--; 1584 1585 if (device->missing) 1586 root->fs_info->fs_devices->missing_devices--; 1587 1588 next_device = list_entry(root->fs_info->fs_devices->devices.next, 1589 struct btrfs_device, dev_list); 1590 if (device->bdev == root->fs_info->sb->s_bdev) 1591 root->fs_info->sb->s_bdev = next_device->bdev; 1592 if (device->bdev == root->fs_info->fs_devices->latest_bdev) 1593 root->fs_info->fs_devices->latest_bdev = next_device->bdev; 1594 1595 if (device->bdev) 1596 device->fs_devices->open_devices--; 1597 1598 call_rcu(&device->rcu, free_device); 1599 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1600 1601 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1; 1602 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices); 1603 1604 if (cur_devices->open_devices == 0) { 1605 struct btrfs_fs_devices *fs_devices; 1606 fs_devices = root->fs_info->fs_devices; 1607 while (fs_devices) { 1608 if (fs_devices->seed == cur_devices) 1609 break; 1610 fs_devices = fs_devices->seed; 1611 } 1612 fs_devices->seed = cur_devices->seed; 1613 cur_devices->seed = NULL; 1614 lock_chunks(root); 1615 __btrfs_close_devices(cur_devices); 1616 unlock_chunks(root); 1617 free_fs_devices(cur_devices); 1618 } 1619 1620 root->fs_info->num_tolerated_disk_barrier_failures = 1621 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 1622 1623 /* 1624 * at this point, the device is zero sized. We want to 1625 * remove it from the devices list and zero out the old super 1626 */ 1627 if (clear_super && disk_super) { 1628 /* make sure this device isn't detected as part of 1629 * the FS anymore 1630 */ 1631 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 1632 set_buffer_dirty(bh); 1633 sync_dirty_buffer(bh); 1634 } 1635 1636 ret = 0; 1637 1638 /* Notify udev that device has changed */ 1639 if (bdev) 1640 btrfs_kobject_uevent(bdev, KOBJ_CHANGE); 1641 1642 error_brelse: 1643 brelse(bh); 1644 if (bdev) 1645 blkdev_put(bdev, FMODE_READ | FMODE_EXCL); 1646 out: 1647 mutex_unlock(&uuid_mutex); 1648 return ret; 1649 error_undo: 1650 if (device->writeable) { 1651 lock_chunks(root); 1652 list_add(&device->dev_alloc_list, 1653 &root->fs_info->fs_devices->alloc_list); 1654 unlock_chunks(root); 1655 root->fs_info->fs_devices->rw_devices++; 1656 } 1657 goto error_brelse; 1658 } 1659 1660 void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info, 1661 struct btrfs_device *srcdev) 1662 { 1663 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex)); 1664 list_del_rcu(&srcdev->dev_list); 1665 list_del_rcu(&srcdev->dev_alloc_list); 1666 fs_info->fs_devices->num_devices--; 1667 if (srcdev->missing) { 1668 fs_info->fs_devices->missing_devices--; 1669 fs_info->fs_devices->rw_devices++; 1670 } 1671 if (srcdev->can_discard) 1672 fs_info->fs_devices->num_can_discard--; 1673 if (srcdev->bdev) 1674 fs_info->fs_devices->open_devices--; 1675 1676 call_rcu(&srcdev->rcu, free_device); 1677 } 1678 1679 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 1680 struct btrfs_device *tgtdev) 1681 { 1682 struct btrfs_device *next_device; 1683 1684 WARN_ON(!tgtdev); 1685 mutex_lock(&fs_info->fs_devices->device_list_mutex); 1686 if (tgtdev->bdev) { 1687 btrfs_scratch_superblock(tgtdev); 1688 fs_info->fs_devices->open_devices--; 1689 } 1690 fs_info->fs_devices->num_devices--; 1691 if (tgtdev->can_discard) 1692 fs_info->fs_devices->num_can_discard++; 1693 1694 next_device = list_entry(fs_info->fs_devices->devices.next, 1695 struct btrfs_device, dev_list); 1696 if (tgtdev->bdev == fs_info->sb->s_bdev) 1697 fs_info->sb->s_bdev = next_device->bdev; 1698 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev) 1699 fs_info->fs_devices->latest_bdev = next_device->bdev; 1700 list_del_rcu(&tgtdev->dev_list); 1701 1702 call_rcu(&tgtdev->rcu, free_device); 1703 1704 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 1705 } 1706 1707 int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path, 1708 struct btrfs_device **device) 1709 { 1710 int ret = 0; 1711 struct btrfs_super_block *disk_super; 1712 u64 devid; 1713 u8 *dev_uuid; 1714 struct block_device *bdev; 1715 struct buffer_head *bh; 1716 1717 *device = NULL; 1718 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ, 1719 root->fs_info->bdev_holder, 0, &bdev, &bh); 1720 if (ret) 1721 return ret; 1722 disk_super = (struct btrfs_super_block *)bh->b_data; 1723 devid = btrfs_stack_device_id(&disk_super->dev_item); 1724 dev_uuid = disk_super->dev_item.uuid; 1725 *device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1726 disk_super->fsid); 1727 brelse(bh); 1728 if (!*device) 1729 ret = -ENOENT; 1730 blkdev_put(bdev, FMODE_READ); 1731 return ret; 1732 } 1733 1734 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root, 1735 char *device_path, 1736 struct btrfs_device **device) 1737 { 1738 *device = NULL; 1739 if (strcmp(device_path, "missing") == 0) { 1740 struct list_head *devices; 1741 struct btrfs_device *tmp; 1742 1743 devices = &root->fs_info->fs_devices->devices; 1744 /* 1745 * It is safe to read the devices since the volume_mutex 1746 * is held by the caller. 1747 */ 1748 list_for_each_entry(tmp, devices, dev_list) { 1749 if (tmp->in_fs_metadata && !tmp->bdev) { 1750 *device = tmp; 1751 break; 1752 } 1753 } 1754 1755 if (!*device) { 1756 pr_err("btrfs: no missing device found\n"); 1757 return -ENOENT; 1758 } 1759 1760 return 0; 1761 } else { 1762 return btrfs_find_device_by_path(root, device_path, device); 1763 } 1764 } 1765 1766 /* 1767 * does all the dirty work required for changing file system's UUID. 1768 */ 1769 static int btrfs_prepare_sprout(struct btrfs_root *root) 1770 { 1771 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 1772 struct btrfs_fs_devices *old_devices; 1773 struct btrfs_fs_devices *seed_devices; 1774 struct btrfs_super_block *disk_super = root->fs_info->super_copy; 1775 struct btrfs_device *device; 1776 u64 super_flags; 1777 1778 BUG_ON(!mutex_is_locked(&uuid_mutex)); 1779 if (!fs_devices->seeding) 1780 return -EINVAL; 1781 1782 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 1783 if (!seed_devices) 1784 return -ENOMEM; 1785 1786 old_devices = clone_fs_devices(fs_devices); 1787 if (IS_ERR(old_devices)) { 1788 kfree(seed_devices); 1789 return PTR_ERR(old_devices); 1790 } 1791 1792 list_add(&old_devices->list, &fs_uuids); 1793 1794 memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); 1795 seed_devices->opened = 1; 1796 INIT_LIST_HEAD(&seed_devices->devices); 1797 INIT_LIST_HEAD(&seed_devices->alloc_list); 1798 mutex_init(&seed_devices->device_list_mutex); 1799 1800 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1801 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, 1802 synchronize_rcu); 1803 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1804 1805 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); 1806 list_for_each_entry(device, &seed_devices->devices, dev_list) { 1807 device->fs_devices = seed_devices; 1808 } 1809 1810 fs_devices->seeding = 0; 1811 fs_devices->num_devices = 0; 1812 fs_devices->open_devices = 0; 1813 fs_devices->total_devices = 0; 1814 fs_devices->seed = seed_devices; 1815 1816 generate_random_uuid(fs_devices->fsid); 1817 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1818 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1819 super_flags = btrfs_super_flags(disk_super) & 1820 ~BTRFS_SUPER_FLAG_SEEDING; 1821 btrfs_set_super_flags(disk_super, super_flags); 1822 1823 return 0; 1824 } 1825 1826 /* 1827 * strore the expected generation for seed devices in device items. 1828 */ 1829 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans, 1830 struct btrfs_root *root) 1831 { 1832 struct btrfs_path *path; 1833 struct extent_buffer *leaf; 1834 struct btrfs_dev_item *dev_item; 1835 struct btrfs_device *device; 1836 struct btrfs_key key; 1837 u8 fs_uuid[BTRFS_UUID_SIZE]; 1838 u8 dev_uuid[BTRFS_UUID_SIZE]; 1839 u64 devid; 1840 int ret; 1841 1842 path = btrfs_alloc_path(); 1843 if (!path) 1844 return -ENOMEM; 1845 1846 root = root->fs_info->chunk_root; 1847 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1848 key.offset = 0; 1849 key.type = BTRFS_DEV_ITEM_KEY; 1850 1851 while (1) { 1852 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 1853 if (ret < 0) 1854 goto error; 1855 1856 leaf = path->nodes[0]; 1857 next_slot: 1858 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1859 ret = btrfs_next_leaf(root, path); 1860 if (ret > 0) 1861 break; 1862 if (ret < 0) 1863 goto error; 1864 leaf = path->nodes[0]; 1865 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1866 btrfs_release_path(path); 1867 continue; 1868 } 1869 1870 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1871 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || 1872 key.type != BTRFS_DEV_ITEM_KEY) 1873 break; 1874 1875 dev_item = btrfs_item_ptr(leaf, path->slots[0], 1876 struct btrfs_dev_item); 1877 devid = btrfs_device_id(leaf, dev_item); 1878 read_extent_buffer(leaf, dev_uuid, 1879 (unsigned long)btrfs_device_uuid(dev_item), 1880 BTRFS_UUID_SIZE); 1881 read_extent_buffer(leaf, fs_uuid, 1882 (unsigned long)btrfs_device_fsid(dev_item), 1883 BTRFS_UUID_SIZE); 1884 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1885 fs_uuid); 1886 BUG_ON(!device); /* Logic error */ 1887 1888 if (device->fs_devices->seeding) { 1889 btrfs_set_device_generation(leaf, dev_item, 1890 device->generation); 1891 btrfs_mark_buffer_dirty(leaf); 1892 } 1893 1894 path->slots[0]++; 1895 goto next_slot; 1896 } 1897 ret = 0; 1898 error: 1899 btrfs_free_path(path); 1900 return ret; 1901 } 1902 1903 int btrfs_init_new_device(struct btrfs_root *root, char *device_path) 1904 { 1905 struct request_queue *q; 1906 struct btrfs_trans_handle *trans; 1907 struct btrfs_device *device; 1908 struct block_device *bdev; 1909 struct list_head *devices; 1910 struct super_block *sb = root->fs_info->sb; 1911 struct rcu_string *name; 1912 u64 total_bytes; 1913 int seeding_dev = 0; 1914 int ret = 0; 1915 1916 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) 1917 return -EROFS; 1918 1919 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 1920 root->fs_info->bdev_holder); 1921 if (IS_ERR(bdev)) 1922 return PTR_ERR(bdev); 1923 1924 if (root->fs_info->fs_devices->seeding) { 1925 seeding_dev = 1; 1926 down_write(&sb->s_umount); 1927 mutex_lock(&uuid_mutex); 1928 } 1929 1930 filemap_write_and_wait(bdev->bd_inode->i_mapping); 1931 1932 devices = &root->fs_info->fs_devices->devices; 1933 1934 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1935 list_for_each_entry(device, devices, dev_list) { 1936 if (device->bdev == bdev) { 1937 ret = -EEXIST; 1938 mutex_unlock( 1939 &root->fs_info->fs_devices->device_list_mutex); 1940 goto error; 1941 } 1942 } 1943 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1944 1945 device = kzalloc(sizeof(*device), GFP_NOFS); 1946 if (!device) { 1947 /* we can safely leave the fs_devices entry around */ 1948 ret = -ENOMEM; 1949 goto error; 1950 } 1951 1952 name = rcu_string_strdup(device_path, GFP_NOFS); 1953 if (!name) { 1954 kfree(device); 1955 ret = -ENOMEM; 1956 goto error; 1957 } 1958 rcu_assign_pointer(device->name, name); 1959 1960 ret = find_next_devid(root, &device->devid); 1961 if (ret) { 1962 rcu_string_free(device->name); 1963 kfree(device); 1964 goto error; 1965 } 1966 1967 trans = btrfs_start_transaction(root, 0); 1968 if (IS_ERR(trans)) { 1969 rcu_string_free(device->name); 1970 kfree(device); 1971 ret = PTR_ERR(trans); 1972 goto error; 1973 } 1974 1975 lock_chunks(root); 1976 1977 q = bdev_get_queue(bdev); 1978 if (blk_queue_discard(q)) 1979 device->can_discard = 1; 1980 device->writeable = 1; 1981 device->work.func = pending_bios_fn; 1982 generate_random_uuid(device->uuid); 1983 spin_lock_init(&device->io_lock); 1984 device->generation = trans->transid; 1985 device->io_width = root->sectorsize; 1986 device->io_align = root->sectorsize; 1987 device->sector_size = root->sectorsize; 1988 device->total_bytes = i_size_read(bdev->bd_inode); 1989 device->disk_total_bytes = device->total_bytes; 1990 device->dev_root = root->fs_info->dev_root; 1991 device->bdev = bdev; 1992 device->in_fs_metadata = 1; 1993 device->is_tgtdev_for_dev_replace = 0; 1994 device->mode = FMODE_EXCL; 1995 set_blocksize(device->bdev, 4096); 1996 1997 if (seeding_dev) { 1998 sb->s_flags &= ~MS_RDONLY; 1999 ret = btrfs_prepare_sprout(root); 2000 BUG_ON(ret); /* -ENOMEM */ 2001 } 2002 2003 device->fs_devices = root->fs_info->fs_devices; 2004 2005 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2006 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices); 2007 list_add(&device->dev_alloc_list, 2008 &root->fs_info->fs_devices->alloc_list); 2009 root->fs_info->fs_devices->num_devices++; 2010 root->fs_info->fs_devices->open_devices++; 2011 root->fs_info->fs_devices->rw_devices++; 2012 root->fs_info->fs_devices->total_devices++; 2013 if (device->can_discard) 2014 root->fs_info->fs_devices->num_can_discard++; 2015 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes; 2016 2017 spin_lock(&root->fs_info->free_chunk_lock); 2018 root->fs_info->free_chunk_space += device->total_bytes; 2019 spin_unlock(&root->fs_info->free_chunk_lock); 2020 2021 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 2022 root->fs_info->fs_devices->rotating = 1; 2023 2024 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); 2025 btrfs_set_super_total_bytes(root->fs_info->super_copy, 2026 total_bytes + device->total_bytes); 2027 2028 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy); 2029 btrfs_set_super_num_devices(root->fs_info->super_copy, 2030 total_bytes + 1); 2031 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2032 2033 if (seeding_dev) { 2034 ret = init_first_rw_device(trans, root, device); 2035 if (ret) { 2036 btrfs_abort_transaction(trans, root, ret); 2037 goto error_trans; 2038 } 2039 ret = btrfs_finish_sprout(trans, root); 2040 if (ret) { 2041 btrfs_abort_transaction(trans, root, ret); 2042 goto error_trans; 2043 } 2044 } else { 2045 ret = btrfs_add_device(trans, root, device); 2046 if (ret) { 2047 btrfs_abort_transaction(trans, root, ret); 2048 goto error_trans; 2049 } 2050 } 2051 2052 /* 2053 * we've got more storage, clear any full flags on the space 2054 * infos 2055 */ 2056 btrfs_clear_space_info_full(root->fs_info); 2057 2058 unlock_chunks(root); 2059 root->fs_info->num_tolerated_disk_barrier_failures = 2060 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 2061 ret = btrfs_commit_transaction(trans, root); 2062 2063 if (seeding_dev) { 2064 mutex_unlock(&uuid_mutex); 2065 up_write(&sb->s_umount); 2066 2067 if (ret) /* transaction commit */ 2068 return ret; 2069 2070 ret = btrfs_relocate_sys_chunks(root); 2071 if (ret < 0) 2072 btrfs_error(root->fs_info, ret, 2073 "Failed to relocate sys chunks after " 2074 "device initialization. This can be fixed " 2075 "using the \"btrfs balance\" command."); 2076 trans = btrfs_attach_transaction(root); 2077 if (IS_ERR(trans)) { 2078 if (PTR_ERR(trans) == -ENOENT) 2079 return 0; 2080 return PTR_ERR(trans); 2081 } 2082 ret = btrfs_commit_transaction(trans, root); 2083 } 2084 2085 return ret; 2086 2087 error_trans: 2088 unlock_chunks(root); 2089 btrfs_end_transaction(trans, root); 2090 rcu_string_free(device->name); 2091 kfree(device); 2092 error: 2093 blkdev_put(bdev, FMODE_EXCL); 2094 if (seeding_dev) { 2095 mutex_unlock(&uuid_mutex); 2096 up_write(&sb->s_umount); 2097 } 2098 return ret; 2099 } 2100 2101 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path, 2102 struct btrfs_device **device_out) 2103 { 2104 struct request_queue *q; 2105 struct btrfs_device *device; 2106 struct block_device *bdev; 2107 struct btrfs_fs_info *fs_info = root->fs_info; 2108 struct list_head *devices; 2109 struct rcu_string *name; 2110 int ret = 0; 2111 2112 *device_out = NULL; 2113 if (fs_info->fs_devices->seeding) 2114 return -EINVAL; 2115 2116 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 2117 fs_info->bdev_holder); 2118 if (IS_ERR(bdev)) 2119 return PTR_ERR(bdev); 2120 2121 filemap_write_and_wait(bdev->bd_inode->i_mapping); 2122 2123 devices = &fs_info->fs_devices->devices; 2124 list_for_each_entry(device, devices, dev_list) { 2125 if (device->bdev == bdev) { 2126 ret = -EEXIST; 2127 goto error; 2128 } 2129 } 2130 2131 device = kzalloc(sizeof(*device), GFP_NOFS); 2132 if (!device) { 2133 ret = -ENOMEM; 2134 goto error; 2135 } 2136 2137 name = rcu_string_strdup(device_path, GFP_NOFS); 2138 if (!name) { 2139 kfree(device); 2140 ret = -ENOMEM; 2141 goto error; 2142 } 2143 rcu_assign_pointer(device->name, name); 2144 2145 q = bdev_get_queue(bdev); 2146 if (blk_queue_discard(q)) 2147 device->can_discard = 1; 2148 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2149 device->writeable = 1; 2150 device->work.func = pending_bios_fn; 2151 generate_random_uuid(device->uuid); 2152 device->devid = BTRFS_DEV_REPLACE_DEVID; 2153 spin_lock_init(&device->io_lock); 2154 device->generation = 0; 2155 device->io_width = root->sectorsize; 2156 device->io_align = root->sectorsize; 2157 device->sector_size = root->sectorsize; 2158 device->total_bytes = i_size_read(bdev->bd_inode); 2159 device->disk_total_bytes = device->total_bytes; 2160 device->dev_root = fs_info->dev_root; 2161 device->bdev = bdev; 2162 device->in_fs_metadata = 1; 2163 device->is_tgtdev_for_dev_replace = 1; 2164 device->mode = FMODE_EXCL; 2165 set_blocksize(device->bdev, 4096); 2166 device->fs_devices = fs_info->fs_devices; 2167 list_add(&device->dev_list, &fs_info->fs_devices->devices); 2168 fs_info->fs_devices->num_devices++; 2169 fs_info->fs_devices->open_devices++; 2170 if (device->can_discard) 2171 fs_info->fs_devices->num_can_discard++; 2172 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2173 2174 *device_out = device; 2175 return ret; 2176 2177 error: 2178 blkdev_put(bdev, FMODE_EXCL); 2179 return ret; 2180 } 2181 2182 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, 2183 struct btrfs_device *tgtdev) 2184 { 2185 WARN_ON(fs_info->fs_devices->rw_devices == 0); 2186 tgtdev->io_width = fs_info->dev_root->sectorsize; 2187 tgtdev->io_align = fs_info->dev_root->sectorsize; 2188 tgtdev->sector_size = fs_info->dev_root->sectorsize; 2189 tgtdev->dev_root = fs_info->dev_root; 2190 tgtdev->in_fs_metadata = 1; 2191 } 2192 2193 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, 2194 struct btrfs_device *device) 2195 { 2196 int ret; 2197 struct btrfs_path *path; 2198 struct btrfs_root *root; 2199 struct btrfs_dev_item *dev_item; 2200 struct extent_buffer *leaf; 2201 struct btrfs_key key; 2202 2203 root = device->dev_root->fs_info->chunk_root; 2204 2205 path = btrfs_alloc_path(); 2206 if (!path) 2207 return -ENOMEM; 2208 2209 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 2210 key.type = BTRFS_DEV_ITEM_KEY; 2211 key.offset = device->devid; 2212 2213 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2214 if (ret < 0) 2215 goto out; 2216 2217 if (ret > 0) { 2218 ret = -ENOENT; 2219 goto out; 2220 } 2221 2222 leaf = path->nodes[0]; 2223 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 2224 2225 btrfs_set_device_id(leaf, dev_item, device->devid); 2226 btrfs_set_device_type(leaf, dev_item, device->type); 2227 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 2228 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 2229 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 2230 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes); 2231 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 2232 btrfs_mark_buffer_dirty(leaf); 2233 2234 out: 2235 btrfs_free_path(path); 2236 return ret; 2237 } 2238 2239 static int __btrfs_grow_device(struct btrfs_trans_handle *trans, 2240 struct btrfs_device *device, u64 new_size) 2241 { 2242 struct btrfs_super_block *super_copy = 2243 device->dev_root->fs_info->super_copy; 2244 u64 old_total = btrfs_super_total_bytes(super_copy); 2245 u64 diff = new_size - device->total_bytes; 2246 2247 if (!device->writeable) 2248 return -EACCES; 2249 if (new_size <= device->total_bytes || 2250 device->is_tgtdev_for_dev_replace) 2251 return -EINVAL; 2252 2253 btrfs_set_super_total_bytes(super_copy, old_total + diff); 2254 device->fs_devices->total_rw_bytes += diff; 2255 2256 device->total_bytes = new_size; 2257 device->disk_total_bytes = new_size; 2258 btrfs_clear_space_info_full(device->dev_root->fs_info); 2259 2260 return btrfs_update_device(trans, device); 2261 } 2262 2263 int btrfs_grow_device(struct btrfs_trans_handle *trans, 2264 struct btrfs_device *device, u64 new_size) 2265 { 2266 int ret; 2267 lock_chunks(device->dev_root); 2268 ret = __btrfs_grow_device(trans, device, new_size); 2269 unlock_chunks(device->dev_root); 2270 return ret; 2271 } 2272 2273 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, 2274 struct btrfs_root *root, 2275 u64 chunk_tree, u64 chunk_objectid, 2276 u64 chunk_offset) 2277 { 2278 int ret; 2279 struct btrfs_path *path; 2280 struct btrfs_key key; 2281 2282 root = root->fs_info->chunk_root; 2283 path = btrfs_alloc_path(); 2284 if (!path) 2285 return -ENOMEM; 2286 2287 key.objectid = chunk_objectid; 2288 key.offset = chunk_offset; 2289 key.type = BTRFS_CHUNK_ITEM_KEY; 2290 2291 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2292 if (ret < 0) 2293 goto out; 2294 else if (ret > 0) { /* Logic error or corruption */ 2295 btrfs_error(root->fs_info, -ENOENT, 2296 "Failed lookup while freeing chunk."); 2297 ret = -ENOENT; 2298 goto out; 2299 } 2300 2301 ret = btrfs_del_item(trans, root, path); 2302 if (ret < 0) 2303 btrfs_error(root->fs_info, ret, 2304 "Failed to delete chunk item."); 2305 out: 2306 btrfs_free_path(path); 2307 return ret; 2308 } 2309 2310 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 2311 chunk_offset) 2312 { 2313 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 2314 struct btrfs_disk_key *disk_key; 2315 struct btrfs_chunk *chunk; 2316 u8 *ptr; 2317 int ret = 0; 2318 u32 num_stripes; 2319 u32 array_size; 2320 u32 len = 0; 2321 u32 cur; 2322 struct btrfs_key key; 2323 2324 array_size = btrfs_super_sys_array_size(super_copy); 2325 2326 ptr = super_copy->sys_chunk_array; 2327 cur = 0; 2328 2329 while (cur < array_size) { 2330 disk_key = (struct btrfs_disk_key *)ptr; 2331 btrfs_disk_key_to_cpu(&key, disk_key); 2332 2333 len = sizeof(*disk_key); 2334 2335 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 2336 chunk = (struct btrfs_chunk *)(ptr + len); 2337 num_stripes = btrfs_stack_chunk_num_stripes(chunk); 2338 len += btrfs_chunk_item_size(num_stripes); 2339 } else { 2340 ret = -EIO; 2341 break; 2342 } 2343 if (key.objectid == chunk_objectid && 2344 key.offset == chunk_offset) { 2345 memmove(ptr, ptr + len, array_size - (cur + len)); 2346 array_size -= len; 2347 btrfs_set_super_sys_array_size(super_copy, array_size); 2348 } else { 2349 ptr += len; 2350 cur += len; 2351 } 2352 } 2353 return ret; 2354 } 2355 2356 static int btrfs_relocate_chunk(struct btrfs_root *root, 2357 u64 chunk_tree, u64 chunk_objectid, 2358 u64 chunk_offset) 2359 { 2360 struct extent_map_tree *em_tree; 2361 struct btrfs_root *extent_root; 2362 struct btrfs_trans_handle *trans; 2363 struct extent_map *em; 2364 struct map_lookup *map; 2365 int ret; 2366 int i; 2367 2368 root = root->fs_info->chunk_root; 2369 extent_root = root->fs_info->extent_root; 2370 em_tree = &root->fs_info->mapping_tree.map_tree; 2371 2372 ret = btrfs_can_relocate(extent_root, chunk_offset); 2373 if (ret) 2374 return -ENOSPC; 2375 2376 /* step one, relocate all the extents inside this chunk */ 2377 ret = btrfs_relocate_block_group(extent_root, chunk_offset); 2378 if (ret) 2379 return ret; 2380 2381 trans = btrfs_start_transaction(root, 0); 2382 if (IS_ERR(trans)) { 2383 ret = PTR_ERR(trans); 2384 btrfs_std_error(root->fs_info, ret); 2385 return ret; 2386 } 2387 2388 lock_chunks(root); 2389 2390 /* 2391 * step two, delete the device extents and the 2392 * chunk tree entries 2393 */ 2394 read_lock(&em_tree->lock); 2395 em = lookup_extent_mapping(em_tree, chunk_offset, 1); 2396 read_unlock(&em_tree->lock); 2397 2398 BUG_ON(!em || em->start > chunk_offset || 2399 em->start + em->len < chunk_offset); 2400 map = (struct map_lookup *)em->bdev; 2401 2402 for (i = 0; i < map->num_stripes; i++) { 2403 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, 2404 map->stripes[i].physical); 2405 BUG_ON(ret); 2406 2407 if (map->stripes[i].dev) { 2408 ret = btrfs_update_device(trans, map->stripes[i].dev); 2409 BUG_ON(ret); 2410 } 2411 } 2412 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, 2413 chunk_offset); 2414 2415 BUG_ON(ret); 2416 2417 trace_btrfs_chunk_free(root, map, chunk_offset, em->len); 2418 2419 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 2420 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); 2421 BUG_ON(ret); 2422 } 2423 2424 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset); 2425 BUG_ON(ret); 2426 2427 write_lock(&em_tree->lock); 2428 remove_extent_mapping(em_tree, em); 2429 write_unlock(&em_tree->lock); 2430 2431 kfree(map); 2432 em->bdev = NULL; 2433 2434 /* once for the tree */ 2435 free_extent_map(em); 2436 /* once for us */ 2437 free_extent_map(em); 2438 2439 unlock_chunks(root); 2440 btrfs_end_transaction(trans, root); 2441 return 0; 2442 } 2443 2444 static int btrfs_relocate_sys_chunks(struct btrfs_root *root) 2445 { 2446 struct btrfs_root *chunk_root = root->fs_info->chunk_root; 2447 struct btrfs_path *path; 2448 struct extent_buffer *leaf; 2449 struct btrfs_chunk *chunk; 2450 struct btrfs_key key; 2451 struct btrfs_key found_key; 2452 u64 chunk_tree = chunk_root->root_key.objectid; 2453 u64 chunk_type; 2454 bool retried = false; 2455 int failed = 0; 2456 int ret; 2457 2458 path = btrfs_alloc_path(); 2459 if (!path) 2460 return -ENOMEM; 2461 2462 again: 2463 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2464 key.offset = (u64)-1; 2465 key.type = BTRFS_CHUNK_ITEM_KEY; 2466 2467 while (1) { 2468 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2469 if (ret < 0) 2470 goto error; 2471 BUG_ON(ret == 0); /* Corruption */ 2472 2473 ret = btrfs_previous_item(chunk_root, path, key.objectid, 2474 key.type); 2475 if (ret < 0) 2476 goto error; 2477 if (ret > 0) 2478 break; 2479 2480 leaf = path->nodes[0]; 2481 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2482 2483 chunk = btrfs_item_ptr(leaf, path->slots[0], 2484 struct btrfs_chunk); 2485 chunk_type = btrfs_chunk_type(leaf, chunk); 2486 btrfs_release_path(path); 2487 2488 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { 2489 ret = btrfs_relocate_chunk(chunk_root, chunk_tree, 2490 found_key.objectid, 2491 found_key.offset); 2492 if (ret == -ENOSPC) 2493 failed++; 2494 else if (ret) 2495 BUG(); 2496 } 2497 2498 if (found_key.offset == 0) 2499 break; 2500 key.offset = found_key.offset - 1; 2501 } 2502 ret = 0; 2503 if (failed && !retried) { 2504 failed = 0; 2505 retried = true; 2506 goto again; 2507 } else if (failed && retried) { 2508 WARN_ON(1); 2509 ret = -ENOSPC; 2510 } 2511 error: 2512 btrfs_free_path(path); 2513 return ret; 2514 } 2515 2516 static int insert_balance_item(struct btrfs_root *root, 2517 struct btrfs_balance_control *bctl) 2518 { 2519 struct btrfs_trans_handle *trans; 2520 struct btrfs_balance_item *item; 2521 struct btrfs_disk_balance_args disk_bargs; 2522 struct btrfs_path *path; 2523 struct extent_buffer *leaf; 2524 struct btrfs_key key; 2525 int ret, err; 2526 2527 path = btrfs_alloc_path(); 2528 if (!path) 2529 return -ENOMEM; 2530 2531 trans = btrfs_start_transaction(root, 0); 2532 if (IS_ERR(trans)) { 2533 btrfs_free_path(path); 2534 return PTR_ERR(trans); 2535 } 2536 2537 key.objectid = BTRFS_BALANCE_OBJECTID; 2538 key.type = BTRFS_BALANCE_ITEM_KEY; 2539 key.offset = 0; 2540 2541 ret = btrfs_insert_empty_item(trans, root, path, &key, 2542 sizeof(*item)); 2543 if (ret) 2544 goto out; 2545 2546 leaf = path->nodes[0]; 2547 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 2548 2549 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); 2550 2551 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); 2552 btrfs_set_balance_data(leaf, item, &disk_bargs); 2553 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); 2554 btrfs_set_balance_meta(leaf, item, &disk_bargs); 2555 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); 2556 btrfs_set_balance_sys(leaf, item, &disk_bargs); 2557 2558 btrfs_set_balance_flags(leaf, item, bctl->flags); 2559 2560 btrfs_mark_buffer_dirty(leaf); 2561 out: 2562 btrfs_free_path(path); 2563 err = btrfs_commit_transaction(trans, root); 2564 if (err && !ret) 2565 ret = err; 2566 return ret; 2567 } 2568 2569 static int del_balance_item(struct btrfs_root *root) 2570 { 2571 struct btrfs_trans_handle *trans; 2572 struct btrfs_path *path; 2573 struct btrfs_key key; 2574 int ret, err; 2575 2576 path = btrfs_alloc_path(); 2577 if (!path) 2578 return -ENOMEM; 2579 2580 trans = btrfs_start_transaction(root, 0); 2581 if (IS_ERR(trans)) { 2582 btrfs_free_path(path); 2583 return PTR_ERR(trans); 2584 } 2585 2586 key.objectid = BTRFS_BALANCE_OBJECTID; 2587 key.type = BTRFS_BALANCE_ITEM_KEY; 2588 key.offset = 0; 2589 2590 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2591 if (ret < 0) 2592 goto out; 2593 if (ret > 0) { 2594 ret = -ENOENT; 2595 goto out; 2596 } 2597 2598 ret = btrfs_del_item(trans, root, path); 2599 out: 2600 btrfs_free_path(path); 2601 err = btrfs_commit_transaction(trans, root); 2602 if (err && !ret) 2603 ret = err; 2604 return ret; 2605 } 2606 2607 /* 2608 * This is a heuristic used to reduce the number of chunks balanced on 2609 * resume after balance was interrupted. 2610 */ 2611 static void update_balance_args(struct btrfs_balance_control *bctl) 2612 { 2613 /* 2614 * Turn on soft mode for chunk types that were being converted. 2615 */ 2616 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) 2617 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; 2618 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) 2619 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; 2620 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) 2621 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; 2622 2623 /* 2624 * Turn on usage filter if is not already used. The idea is 2625 * that chunks that we have already balanced should be 2626 * reasonably full. Don't do it for chunks that are being 2627 * converted - that will keep us from relocating unconverted 2628 * (albeit full) chunks. 2629 */ 2630 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && 2631 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2632 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; 2633 bctl->data.usage = 90; 2634 } 2635 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && 2636 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2637 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; 2638 bctl->sys.usage = 90; 2639 } 2640 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && 2641 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2642 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; 2643 bctl->meta.usage = 90; 2644 } 2645 } 2646 2647 /* 2648 * Should be called with both balance and volume mutexes held to 2649 * serialize other volume operations (add_dev/rm_dev/resize) with 2650 * restriper. Same goes for unset_balance_control. 2651 */ 2652 static void set_balance_control(struct btrfs_balance_control *bctl) 2653 { 2654 struct btrfs_fs_info *fs_info = bctl->fs_info; 2655 2656 BUG_ON(fs_info->balance_ctl); 2657 2658 spin_lock(&fs_info->balance_lock); 2659 fs_info->balance_ctl = bctl; 2660 spin_unlock(&fs_info->balance_lock); 2661 } 2662 2663 static void unset_balance_control(struct btrfs_fs_info *fs_info) 2664 { 2665 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2666 2667 BUG_ON(!fs_info->balance_ctl); 2668 2669 spin_lock(&fs_info->balance_lock); 2670 fs_info->balance_ctl = NULL; 2671 spin_unlock(&fs_info->balance_lock); 2672 2673 kfree(bctl); 2674 } 2675 2676 /* 2677 * Balance filters. Return 1 if chunk should be filtered out 2678 * (should not be balanced). 2679 */ 2680 static int chunk_profiles_filter(u64 chunk_type, 2681 struct btrfs_balance_args *bargs) 2682 { 2683 chunk_type = chunk_to_extended(chunk_type) & 2684 BTRFS_EXTENDED_PROFILE_MASK; 2685 2686 if (bargs->profiles & chunk_type) 2687 return 0; 2688 2689 return 1; 2690 } 2691 2692 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, 2693 struct btrfs_balance_args *bargs) 2694 { 2695 struct btrfs_block_group_cache *cache; 2696 u64 chunk_used, user_thresh; 2697 int ret = 1; 2698 2699 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 2700 chunk_used = btrfs_block_group_used(&cache->item); 2701 2702 if (bargs->usage == 0) 2703 user_thresh = 1; 2704 else if (bargs->usage > 100) 2705 user_thresh = cache->key.offset; 2706 else 2707 user_thresh = div_factor_fine(cache->key.offset, 2708 bargs->usage); 2709 2710 if (chunk_used < user_thresh) 2711 ret = 0; 2712 2713 btrfs_put_block_group(cache); 2714 return ret; 2715 } 2716 2717 static int chunk_devid_filter(struct extent_buffer *leaf, 2718 struct btrfs_chunk *chunk, 2719 struct btrfs_balance_args *bargs) 2720 { 2721 struct btrfs_stripe *stripe; 2722 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2723 int i; 2724 2725 for (i = 0; i < num_stripes; i++) { 2726 stripe = btrfs_stripe_nr(chunk, i); 2727 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) 2728 return 0; 2729 } 2730 2731 return 1; 2732 } 2733 2734 /* [pstart, pend) */ 2735 static int chunk_drange_filter(struct extent_buffer *leaf, 2736 struct btrfs_chunk *chunk, 2737 u64 chunk_offset, 2738 struct btrfs_balance_args *bargs) 2739 { 2740 struct btrfs_stripe *stripe; 2741 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2742 u64 stripe_offset; 2743 u64 stripe_length; 2744 int factor; 2745 int i; 2746 2747 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) 2748 return 0; 2749 2750 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP | 2751 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) { 2752 factor = num_stripes / 2; 2753 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) { 2754 factor = num_stripes - 1; 2755 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) { 2756 factor = num_stripes - 2; 2757 } else { 2758 factor = num_stripes; 2759 } 2760 2761 for (i = 0; i < num_stripes; i++) { 2762 stripe = btrfs_stripe_nr(chunk, i); 2763 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) 2764 continue; 2765 2766 stripe_offset = btrfs_stripe_offset(leaf, stripe); 2767 stripe_length = btrfs_chunk_length(leaf, chunk); 2768 do_div(stripe_length, factor); 2769 2770 if (stripe_offset < bargs->pend && 2771 stripe_offset + stripe_length > bargs->pstart) 2772 return 0; 2773 } 2774 2775 return 1; 2776 } 2777 2778 /* [vstart, vend) */ 2779 static int chunk_vrange_filter(struct extent_buffer *leaf, 2780 struct btrfs_chunk *chunk, 2781 u64 chunk_offset, 2782 struct btrfs_balance_args *bargs) 2783 { 2784 if (chunk_offset < bargs->vend && 2785 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) 2786 /* at least part of the chunk is inside this vrange */ 2787 return 0; 2788 2789 return 1; 2790 } 2791 2792 static int chunk_soft_convert_filter(u64 chunk_type, 2793 struct btrfs_balance_args *bargs) 2794 { 2795 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) 2796 return 0; 2797 2798 chunk_type = chunk_to_extended(chunk_type) & 2799 BTRFS_EXTENDED_PROFILE_MASK; 2800 2801 if (bargs->target == chunk_type) 2802 return 1; 2803 2804 return 0; 2805 } 2806 2807 static int should_balance_chunk(struct btrfs_root *root, 2808 struct extent_buffer *leaf, 2809 struct btrfs_chunk *chunk, u64 chunk_offset) 2810 { 2811 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl; 2812 struct btrfs_balance_args *bargs = NULL; 2813 u64 chunk_type = btrfs_chunk_type(leaf, chunk); 2814 2815 /* type filter */ 2816 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & 2817 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { 2818 return 0; 2819 } 2820 2821 if (chunk_type & BTRFS_BLOCK_GROUP_DATA) 2822 bargs = &bctl->data; 2823 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) 2824 bargs = &bctl->sys; 2825 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) 2826 bargs = &bctl->meta; 2827 2828 /* profiles filter */ 2829 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && 2830 chunk_profiles_filter(chunk_type, bargs)) { 2831 return 0; 2832 } 2833 2834 /* usage filter */ 2835 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && 2836 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) { 2837 return 0; 2838 } 2839 2840 /* devid filter */ 2841 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && 2842 chunk_devid_filter(leaf, chunk, bargs)) { 2843 return 0; 2844 } 2845 2846 /* drange filter, makes sense only with devid filter */ 2847 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && 2848 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) { 2849 return 0; 2850 } 2851 2852 /* vrange filter */ 2853 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && 2854 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { 2855 return 0; 2856 } 2857 2858 /* soft profile changing mode */ 2859 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && 2860 chunk_soft_convert_filter(chunk_type, bargs)) { 2861 return 0; 2862 } 2863 2864 return 1; 2865 } 2866 2867 static int __btrfs_balance(struct btrfs_fs_info *fs_info) 2868 { 2869 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2870 struct btrfs_root *chunk_root = fs_info->chunk_root; 2871 struct btrfs_root *dev_root = fs_info->dev_root; 2872 struct list_head *devices; 2873 struct btrfs_device *device; 2874 u64 old_size; 2875 u64 size_to_free; 2876 struct btrfs_chunk *chunk; 2877 struct btrfs_path *path; 2878 struct btrfs_key key; 2879 struct btrfs_key found_key; 2880 struct btrfs_trans_handle *trans; 2881 struct extent_buffer *leaf; 2882 int slot; 2883 int ret; 2884 int enospc_errors = 0; 2885 bool counting = true; 2886 2887 /* step one make some room on all the devices */ 2888 devices = &fs_info->fs_devices->devices; 2889 list_for_each_entry(device, devices, dev_list) { 2890 old_size = device->total_bytes; 2891 size_to_free = div_factor(old_size, 1); 2892 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024); 2893 if (!device->writeable || 2894 device->total_bytes - device->bytes_used > size_to_free || 2895 device->is_tgtdev_for_dev_replace) 2896 continue; 2897 2898 ret = btrfs_shrink_device(device, old_size - size_to_free); 2899 if (ret == -ENOSPC) 2900 break; 2901 BUG_ON(ret); 2902 2903 trans = btrfs_start_transaction(dev_root, 0); 2904 BUG_ON(IS_ERR(trans)); 2905 2906 ret = btrfs_grow_device(trans, device, old_size); 2907 BUG_ON(ret); 2908 2909 btrfs_end_transaction(trans, dev_root); 2910 } 2911 2912 /* step two, relocate all the chunks */ 2913 path = btrfs_alloc_path(); 2914 if (!path) { 2915 ret = -ENOMEM; 2916 goto error; 2917 } 2918 2919 /* zero out stat counters */ 2920 spin_lock(&fs_info->balance_lock); 2921 memset(&bctl->stat, 0, sizeof(bctl->stat)); 2922 spin_unlock(&fs_info->balance_lock); 2923 again: 2924 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2925 key.offset = (u64)-1; 2926 key.type = BTRFS_CHUNK_ITEM_KEY; 2927 2928 while (1) { 2929 if ((!counting && atomic_read(&fs_info->balance_pause_req)) || 2930 atomic_read(&fs_info->balance_cancel_req)) { 2931 ret = -ECANCELED; 2932 goto error; 2933 } 2934 2935 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2936 if (ret < 0) 2937 goto error; 2938 2939 /* 2940 * this shouldn't happen, it means the last relocate 2941 * failed 2942 */ 2943 if (ret == 0) 2944 BUG(); /* FIXME break ? */ 2945 2946 ret = btrfs_previous_item(chunk_root, path, 0, 2947 BTRFS_CHUNK_ITEM_KEY); 2948 if (ret) { 2949 ret = 0; 2950 break; 2951 } 2952 2953 leaf = path->nodes[0]; 2954 slot = path->slots[0]; 2955 btrfs_item_key_to_cpu(leaf, &found_key, slot); 2956 2957 if (found_key.objectid != key.objectid) 2958 break; 2959 2960 /* chunk zero is special */ 2961 if (found_key.offset == 0) 2962 break; 2963 2964 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 2965 2966 if (!counting) { 2967 spin_lock(&fs_info->balance_lock); 2968 bctl->stat.considered++; 2969 spin_unlock(&fs_info->balance_lock); 2970 } 2971 2972 ret = should_balance_chunk(chunk_root, leaf, chunk, 2973 found_key.offset); 2974 btrfs_release_path(path); 2975 if (!ret) 2976 goto loop; 2977 2978 if (counting) { 2979 spin_lock(&fs_info->balance_lock); 2980 bctl->stat.expected++; 2981 spin_unlock(&fs_info->balance_lock); 2982 goto loop; 2983 } 2984 2985 ret = btrfs_relocate_chunk(chunk_root, 2986 chunk_root->root_key.objectid, 2987 found_key.objectid, 2988 found_key.offset); 2989 if (ret && ret != -ENOSPC) 2990 goto error; 2991 if (ret == -ENOSPC) { 2992 enospc_errors++; 2993 } else { 2994 spin_lock(&fs_info->balance_lock); 2995 bctl->stat.completed++; 2996 spin_unlock(&fs_info->balance_lock); 2997 } 2998 loop: 2999 key.offset = found_key.offset - 1; 3000 } 3001 3002 if (counting) { 3003 btrfs_release_path(path); 3004 counting = false; 3005 goto again; 3006 } 3007 error: 3008 btrfs_free_path(path); 3009 if (enospc_errors) { 3010 printk(KERN_INFO "btrfs: %d enospc errors during balance\n", 3011 enospc_errors); 3012 if (!ret) 3013 ret = -ENOSPC; 3014 } 3015 3016 return ret; 3017 } 3018 3019 /** 3020 * alloc_profile_is_valid - see if a given profile is valid and reduced 3021 * @flags: profile to validate 3022 * @extended: if true @flags is treated as an extended profile 3023 */ 3024 static int alloc_profile_is_valid(u64 flags, int extended) 3025 { 3026 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK : 3027 BTRFS_BLOCK_GROUP_PROFILE_MASK); 3028 3029 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK; 3030 3031 /* 1) check that all other bits are zeroed */ 3032 if (flags & ~mask) 3033 return 0; 3034 3035 /* 2) see if profile is reduced */ 3036 if (flags == 0) 3037 return !extended; /* "0" is valid for usual profiles */ 3038 3039 /* true if exactly one bit set */ 3040 return (flags & (flags - 1)) == 0; 3041 } 3042 3043 static inline int balance_need_close(struct btrfs_fs_info *fs_info) 3044 { 3045 /* cancel requested || normal exit path */ 3046 return atomic_read(&fs_info->balance_cancel_req) || 3047 (atomic_read(&fs_info->balance_pause_req) == 0 && 3048 atomic_read(&fs_info->balance_cancel_req) == 0); 3049 } 3050 3051 static void __cancel_balance(struct btrfs_fs_info *fs_info) 3052 { 3053 int ret; 3054 3055 unset_balance_control(fs_info); 3056 ret = del_balance_item(fs_info->tree_root); 3057 if (ret) 3058 btrfs_std_error(fs_info, ret); 3059 3060 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3061 } 3062 3063 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3064 struct btrfs_ioctl_balance_args *bargs); 3065 3066 /* 3067 * Should be called with both balance and volume mutexes held 3068 */ 3069 int btrfs_balance(struct btrfs_balance_control *bctl, 3070 struct btrfs_ioctl_balance_args *bargs) 3071 { 3072 struct btrfs_fs_info *fs_info = bctl->fs_info; 3073 u64 allowed; 3074 int mixed = 0; 3075 int ret; 3076 u64 num_devices; 3077 unsigned seq; 3078 3079 if (btrfs_fs_closing(fs_info) || 3080 atomic_read(&fs_info->balance_pause_req) || 3081 atomic_read(&fs_info->balance_cancel_req)) { 3082 ret = -EINVAL; 3083 goto out; 3084 } 3085 3086 allowed = btrfs_super_incompat_flags(fs_info->super_copy); 3087 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) 3088 mixed = 1; 3089 3090 /* 3091 * In case of mixed groups both data and meta should be picked, 3092 * and identical options should be given for both of them. 3093 */ 3094 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA; 3095 if (mixed && (bctl->flags & allowed)) { 3096 if (!(bctl->flags & BTRFS_BALANCE_DATA) || 3097 !(bctl->flags & BTRFS_BALANCE_METADATA) || 3098 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { 3099 printk(KERN_ERR "btrfs: with mixed groups data and " 3100 "metadata balance options must be the same\n"); 3101 ret = -EINVAL; 3102 goto out; 3103 } 3104 } 3105 3106 num_devices = fs_info->fs_devices->num_devices; 3107 btrfs_dev_replace_lock(&fs_info->dev_replace); 3108 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { 3109 BUG_ON(num_devices < 1); 3110 num_devices--; 3111 } 3112 btrfs_dev_replace_unlock(&fs_info->dev_replace); 3113 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; 3114 if (num_devices == 1) 3115 allowed |= BTRFS_BLOCK_GROUP_DUP; 3116 else if (num_devices < 4) 3117 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1); 3118 else 3119 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | 3120 BTRFS_BLOCK_GROUP_RAID10 | 3121 BTRFS_BLOCK_GROUP_RAID5 | 3122 BTRFS_BLOCK_GROUP_RAID6); 3123 3124 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3125 (!alloc_profile_is_valid(bctl->data.target, 1) || 3126 (bctl->data.target & ~allowed))) { 3127 printk(KERN_ERR "btrfs: unable to start balance with target " 3128 "data profile %llu\n", 3129 (unsigned long long)bctl->data.target); 3130 ret = -EINVAL; 3131 goto out; 3132 } 3133 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3134 (!alloc_profile_is_valid(bctl->meta.target, 1) || 3135 (bctl->meta.target & ~allowed))) { 3136 printk(KERN_ERR "btrfs: unable to start balance with target " 3137 "metadata profile %llu\n", 3138 (unsigned long long)bctl->meta.target); 3139 ret = -EINVAL; 3140 goto out; 3141 } 3142 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3143 (!alloc_profile_is_valid(bctl->sys.target, 1) || 3144 (bctl->sys.target & ~allowed))) { 3145 printk(KERN_ERR "btrfs: unable to start balance with target " 3146 "system profile %llu\n", 3147 (unsigned long long)bctl->sys.target); 3148 ret = -EINVAL; 3149 goto out; 3150 } 3151 3152 /* allow dup'ed data chunks only in mixed mode */ 3153 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3154 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) { 3155 printk(KERN_ERR "btrfs: dup for data is not allowed\n"); 3156 ret = -EINVAL; 3157 goto out; 3158 } 3159 3160 /* allow to reduce meta or sys integrity only if force set */ 3161 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | 3162 BTRFS_BLOCK_GROUP_RAID10 | 3163 BTRFS_BLOCK_GROUP_RAID5 | 3164 BTRFS_BLOCK_GROUP_RAID6; 3165 do { 3166 seq = read_seqbegin(&fs_info->profiles_lock); 3167 3168 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3169 (fs_info->avail_system_alloc_bits & allowed) && 3170 !(bctl->sys.target & allowed)) || 3171 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3172 (fs_info->avail_metadata_alloc_bits & allowed) && 3173 !(bctl->meta.target & allowed))) { 3174 if (bctl->flags & BTRFS_BALANCE_FORCE) { 3175 printk(KERN_INFO "btrfs: force reducing metadata " 3176 "integrity\n"); 3177 } else { 3178 printk(KERN_ERR "btrfs: balance will reduce metadata " 3179 "integrity, use force if you want this\n"); 3180 ret = -EINVAL; 3181 goto out; 3182 } 3183 } 3184 } while (read_seqretry(&fs_info->profiles_lock, seq)); 3185 3186 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3187 int num_tolerated_disk_barrier_failures; 3188 u64 target = bctl->sys.target; 3189 3190 num_tolerated_disk_barrier_failures = 3191 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3192 if (num_tolerated_disk_barrier_failures > 0 && 3193 (target & 3194 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 | 3195 BTRFS_AVAIL_ALLOC_BIT_SINGLE))) 3196 num_tolerated_disk_barrier_failures = 0; 3197 else if (num_tolerated_disk_barrier_failures > 1 && 3198 (target & 3199 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10))) 3200 num_tolerated_disk_barrier_failures = 1; 3201 3202 fs_info->num_tolerated_disk_barrier_failures = 3203 num_tolerated_disk_barrier_failures; 3204 } 3205 3206 ret = insert_balance_item(fs_info->tree_root, bctl); 3207 if (ret && ret != -EEXIST) 3208 goto out; 3209 3210 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { 3211 BUG_ON(ret == -EEXIST); 3212 set_balance_control(bctl); 3213 } else { 3214 BUG_ON(ret != -EEXIST); 3215 spin_lock(&fs_info->balance_lock); 3216 update_balance_args(bctl); 3217 spin_unlock(&fs_info->balance_lock); 3218 } 3219 3220 atomic_inc(&fs_info->balance_running); 3221 mutex_unlock(&fs_info->balance_mutex); 3222 3223 ret = __btrfs_balance(fs_info); 3224 3225 mutex_lock(&fs_info->balance_mutex); 3226 atomic_dec(&fs_info->balance_running); 3227 3228 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3229 fs_info->num_tolerated_disk_barrier_failures = 3230 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3231 } 3232 3233 if (bargs) { 3234 memset(bargs, 0, sizeof(*bargs)); 3235 update_ioctl_balance_args(fs_info, 0, bargs); 3236 } 3237 3238 if ((ret && ret != -ECANCELED && ret != -ENOSPC) || 3239 balance_need_close(fs_info)) { 3240 __cancel_balance(fs_info); 3241 } 3242 3243 wake_up(&fs_info->balance_wait_q); 3244 3245 return ret; 3246 out: 3247 if (bctl->flags & BTRFS_BALANCE_RESUME) 3248 __cancel_balance(fs_info); 3249 else { 3250 kfree(bctl); 3251 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3252 } 3253 return ret; 3254 } 3255 3256 static int balance_kthread(void *data) 3257 { 3258 struct btrfs_fs_info *fs_info = data; 3259 int ret = 0; 3260 3261 mutex_lock(&fs_info->volume_mutex); 3262 mutex_lock(&fs_info->balance_mutex); 3263 3264 if (fs_info->balance_ctl) { 3265 printk(KERN_INFO "btrfs: continuing balance\n"); 3266 ret = btrfs_balance(fs_info->balance_ctl, NULL); 3267 } 3268 3269 mutex_unlock(&fs_info->balance_mutex); 3270 mutex_unlock(&fs_info->volume_mutex); 3271 3272 return ret; 3273 } 3274 3275 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info) 3276 { 3277 struct task_struct *tsk; 3278 3279 spin_lock(&fs_info->balance_lock); 3280 if (!fs_info->balance_ctl) { 3281 spin_unlock(&fs_info->balance_lock); 3282 return 0; 3283 } 3284 spin_unlock(&fs_info->balance_lock); 3285 3286 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) { 3287 printk(KERN_INFO "btrfs: force skipping balance\n"); 3288 return 0; 3289 } 3290 3291 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance"); 3292 if (IS_ERR(tsk)) 3293 return PTR_ERR(tsk); 3294 3295 return 0; 3296 } 3297 3298 int btrfs_recover_balance(struct btrfs_fs_info *fs_info) 3299 { 3300 struct btrfs_balance_control *bctl; 3301 struct btrfs_balance_item *item; 3302 struct btrfs_disk_balance_args disk_bargs; 3303 struct btrfs_path *path; 3304 struct extent_buffer *leaf; 3305 struct btrfs_key key; 3306 int ret; 3307 3308 path = btrfs_alloc_path(); 3309 if (!path) 3310 return -ENOMEM; 3311 3312 key.objectid = BTRFS_BALANCE_OBJECTID; 3313 key.type = BTRFS_BALANCE_ITEM_KEY; 3314 key.offset = 0; 3315 3316 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 3317 if (ret < 0) 3318 goto out; 3319 if (ret > 0) { /* ret = -ENOENT; */ 3320 ret = 0; 3321 goto out; 3322 } 3323 3324 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3325 if (!bctl) { 3326 ret = -ENOMEM; 3327 goto out; 3328 } 3329 3330 leaf = path->nodes[0]; 3331 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 3332 3333 bctl->fs_info = fs_info; 3334 bctl->flags = btrfs_balance_flags(leaf, item); 3335 bctl->flags |= BTRFS_BALANCE_RESUME; 3336 3337 btrfs_balance_data(leaf, item, &disk_bargs); 3338 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); 3339 btrfs_balance_meta(leaf, item, &disk_bargs); 3340 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); 3341 btrfs_balance_sys(leaf, item, &disk_bargs); 3342 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); 3343 3344 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)); 3345 3346 mutex_lock(&fs_info->volume_mutex); 3347 mutex_lock(&fs_info->balance_mutex); 3348 3349 set_balance_control(bctl); 3350 3351 mutex_unlock(&fs_info->balance_mutex); 3352 mutex_unlock(&fs_info->volume_mutex); 3353 out: 3354 btrfs_free_path(path); 3355 return ret; 3356 } 3357 3358 int btrfs_pause_balance(struct btrfs_fs_info *fs_info) 3359 { 3360 int ret = 0; 3361 3362 mutex_lock(&fs_info->balance_mutex); 3363 if (!fs_info->balance_ctl) { 3364 mutex_unlock(&fs_info->balance_mutex); 3365 return -ENOTCONN; 3366 } 3367 3368 if (atomic_read(&fs_info->balance_running)) { 3369 atomic_inc(&fs_info->balance_pause_req); 3370 mutex_unlock(&fs_info->balance_mutex); 3371 3372 wait_event(fs_info->balance_wait_q, 3373 atomic_read(&fs_info->balance_running) == 0); 3374 3375 mutex_lock(&fs_info->balance_mutex); 3376 /* we are good with balance_ctl ripped off from under us */ 3377 BUG_ON(atomic_read(&fs_info->balance_running)); 3378 atomic_dec(&fs_info->balance_pause_req); 3379 } else { 3380 ret = -ENOTCONN; 3381 } 3382 3383 mutex_unlock(&fs_info->balance_mutex); 3384 return ret; 3385 } 3386 3387 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) 3388 { 3389 mutex_lock(&fs_info->balance_mutex); 3390 if (!fs_info->balance_ctl) { 3391 mutex_unlock(&fs_info->balance_mutex); 3392 return -ENOTCONN; 3393 } 3394 3395 atomic_inc(&fs_info->balance_cancel_req); 3396 /* 3397 * if we are running just wait and return, balance item is 3398 * deleted in btrfs_balance in this case 3399 */ 3400 if (atomic_read(&fs_info->balance_running)) { 3401 mutex_unlock(&fs_info->balance_mutex); 3402 wait_event(fs_info->balance_wait_q, 3403 atomic_read(&fs_info->balance_running) == 0); 3404 mutex_lock(&fs_info->balance_mutex); 3405 } else { 3406 /* __cancel_balance needs volume_mutex */ 3407 mutex_unlock(&fs_info->balance_mutex); 3408 mutex_lock(&fs_info->volume_mutex); 3409 mutex_lock(&fs_info->balance_mutex); 3410 3411 if (fs_info->balance_ctl) 3412 __cancel_balance(fs_info); 3413 3414 mutex_unlock(&fs_info->volume_mutex); 3415 } 3416 3417 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running)); 3418 atomic_dec(&fs_info->balance_cancel_req); 3419 mutex_unlock(&fs_info->balance_mutex); 3420 return 0; 3421 } 3422 3423 /* 3424 * shrinking a device means finding all of the device extents past 3425 * the new size, and then following the back refs to the chunks. 3426 * The chunk relocation code actually frees the device extent 3427 */ 3428 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 3429 { 3430 struct btrfs_trans_handle *trans; 3431 struct btrfs_root *root = device->dev_root; 3432 struct btrfs_dev_extent *dev_extent = NULL; 3433 struct btrfs_path *path; 3434 u64 length; 3435 u64 chunk_tree; 3436 u64 chunk_objectid; 3437 u64 chunk_offset; 3438 int ret; 3439 int slot; 3440 int failed = 0; 3441 bool retried = false; 3442 struct extent_buffer *l; 3443 struct btrfs_key key; 3444 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3445 u64 old_total = btrfs_super_total_bytes(super_copy); 3446 u64 old_size = device->total_bytes; 3447 u64 diff = device->total_bytes - new_size; 3448 3449 if (device->is_tgtdev_for_dev_replace) 3450 return -EINVAL; 3451 3452 path = btrfs_alloc_path(); 3453 if (!path) 3454 return -ENOMEM; 3455 3456 path->reada = 2; 3457 3458 lock_chunks(root); 3459 3460 device->total_bytes = new_size; 3461 if (device->writeable) { 3462 device->fs_devices->total_rw_bytes -= diff; 3463 spin_lock(&root->fs_info->free_chunk_lock); 3464 root->fs_info->free_chunk_space -= diff; 3465 spin_unlock(&root->fs_info->free_chunk_lock); 3466 } 3467 unlock_chunks(root); 3468 3469 again: 3470 key.objectid = device->devid; 3471 key.offset = (u64)-1; 3472 key.type = BTRFS_DEV_EXTENT_KEY; 3473 3474 do { 3475 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3476 if (ret < 0) 3477 goto done; 3478 3479 ret = btrfs_previous_item(root, path, 0, key.type); 3480 if (ret < 0) 3481 goto done; 3482 if (ret) { 3483 ret = 0; 3484 btrfs_release_path(path); 3485 break; 3486 } 3487 3488 l = path->nodes[0]; 3489 slot = path->slots[0]; 3490 btrfs_item_key_to_cpu(l, &key, path->slots[0]); 3491 3492 if (key.objectid != device->devid) { 3493 btrfs_release_path(path); 3494 break; 3495 } 3496 3497 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 3498 length = btrfs_dev_extent_length(l, dev_extent); 3499 3500 if (key.offset + length <= new_size) { 3501 btrfs_release_path(path); 3502 break; 3503 } 3504 3505 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); 3506 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); 3507 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); 3508 btrfs_release_path(path); 3509 3510 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, 3511 chunk_offset); 3512 if (ret && ret != -ENOSPC) 3513 goto done; 3514 if (ret == -ENOSPC) 3515 failed++; 3516 } while (key.offset-- > 0); 3517 3518 if (failed && !retried) { 3519 failed = 0; 3520 retried = true; 3521 goto again; 3522 } else if (failed && retried) { 3523 ret = -ENOSPC; 3524 lock_chunks(root); 3525 3526 device->total_bytes = old_size; 3527 if (device->writeable) 3528 device->fs_devices->total_rw_bytes += diff; 3529 spin_lock(&root->fs_info->free_chunk_lock); 3530 root->fs_info->free_chunk_space += diff; 3531 spin_unlock(&root->fs_info->free_chunk_lock); 3532 unlock_chunks(root); 3533 goto done; 3534 } 3535 3536 /* Shrinking succeeded, else we would be at "done". */ 3537 trans = btrfs_start_transaction(root, 0); 3538 if (IS_ERR(trans)) { 3539 ret = PTR_ERR(trans); 3540 goto done; 3541 } 3542 3543 lock_chunks(root); 3544 3545 device->disk_total_bytes = new_size; 3546 /* Now btrfs_update_device() will change the on-disk size. */ 3547 ret = btrfs_update_device(trans, device); 3548 if (ret) { 3549 unlock_chunks(root); 3550 btrfs_end_transaction(trans, root); 3551 goto done; 3552 } 3553 WARN_ON(diff > old_total); 3554 btrfs_set_super_total_bytes(super_copy, old_total - diff); 3555 unlock_chunks(root); 3556 btrfs_end_transaction(trans, root); 3557 done: 3558 btrfs_free_path(path); 3559 return ret; 3560 } 3561 3562 static int btrfs_add_system_chunk(struct btrfs_root *root, 3563 struct btrfs_key *key, 3564 struct btrfs_chunk *chunk, int item_size) 3565 { 3566 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3567 struct btrfs_disk_key disk_key; 3568 u32 array_size; 3569 u8 *ptr; 3570 3571 array_size = btrfs_super_sys_array_size(super_copy); 3572 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) 3573 return -EFBIG; 3574 3575 ptr = super_copy->sys_chunk_array + array_size; 3576 btrfs_cpu_key_to_disk(&disk_key, key); 3577 memcpy(ptr, &disk_key, sizeof(disk_key)); 3578 ptr += sizeof(disk_key); 3579 memcpy(ptr, chunk, item_size); 3580 item_size += sizeof(disk_key); 3581 btrfs_set_super_sys_array_size(super_copy, array_size + item_size); 3582 return 0; 3583 } 3584 3585 /* 3586 * sort the devices in descending order by max_avail, total_avail 3587 */ 3588 static int btrfs_cmp_device_info(const void *a, const void *b) 3589 { 3590 const struct btrfs_device_info *di_a = a; 3591 const struct btrfs_device_info *di_b = b; 3592 3593 if (di_a->max_avail > di_b->max_avail) 3594 return -1; 3595 if (di_a->max_avail < di_b->max_avail) 3596 return 1; 3597 if (di_a->total_avail > di_b->total_avail) 3598 return -1; 3599 if (di_a->total_avail < di_b->total_avail) 3600 return 1; 3601 return 0; 3602 } 3603 3604 struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { 3605 [BTRFS_RAID_RAID10] = { 3606 .sub_stripes = 2, 3607 .dev_stripes = 1, 3608 .devs_max = 0, /* 0 == as many as possible */ 3609 .devs_min = 4, 3610 .devs_increment = 2, 3611 .ncopies = 2, 3612 }, 3613 [BTRFS_RAID_RAID1] = { 3614 .sub_stripes = 1, 3615 .dev_stripes = 1, 3616 .devs_max = 2, 3617 .devs_min = 2, 3618 .devs_increment = 2, 3619 .ncopies = 2, 3620 }, 3621 [BTRFS_RAID_DUP] = { 3622 .sub_stripes = 1, 3623 .dev_stripes = 2, 3624 .devs_max = 1, 3625 .devs_min = 1, 3626 .devs_increment = 1, 3627 .ncopies = 2, 3628 }, 3629 [BTRFS_RAID_RAID0] = { 3630 .sub_stripes = 1, 3631 .dev_stripes = 1, 3632 .devs_max = 0, 3633 .devs_min = 2, 3634 .devs_increment = 1, 3635 .ncopies = 1, 3636 }, 3637 [BTRFS_RAID_SINGLE] = { 3638 .sub_stripes = 1, 3639 .dev_stripes = 1, 3640 .devs_max = 1, 3641 .devs_min = 1, 3642 .devs_increment = 1, 3643 .ncopies = 1, 3644 }, 3645 [BTRFS_RAID_RAID5] = { 3646 .sub_stripes = 1, 3647 .dev_stripes = 1, 3648 .devs_max = 0, 3649 .devs_min = 2, 3650 .devs_increment = 1, 3651 .ncopies = 2, 3652 }, 3653 [BTRFS_RAID_RAID6] = { 3654 .sub_stripes = 1, 3655 .dev_stripes = 1, 3656 .devs_max = 0, 3657 .devs_min = 3, 3658 .devs_increment = 1, 3659 .ncopies = 3, 3660 }, 3661 }; 3662 3663 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target) 3664 { 3665 /* TODO allow them to set a preferred stripe size */ 3666 return 64 * 1024; 3667 } 3668 3669 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type) 3670 { 3671 u64 features; 3672 3673 if (!(type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))) 3674 return; 3675 3676 features = btrfs_super_incompat_flags(info->super_copy); 3677 if (features & BTRFS_FEATURE_INCOMPAT_RAID56) 3678 return; 3679 3680 features |= BTRFS_FEATURE_INCOMPAT_RAID56; 3681 btrfs_set_super_incompat_flags(info->super_copy, features); 3682 printk(KERN_INFO "btrfs: setting RAID5/6 feature flag\n"); 3683 } 3684 3685 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 3686 struct btrfs_root *extent_root, 3687 struct map_lookup **map_ret, 3688 u64 *num_bytes_out, u64 *stripe_size_out, 3689 u64 start, u64 type) 3690 { 3691 struct btrfs_fs_info *info = extent_root->fs_info; 3692 struct btrfs_fs_devices *fs_devices = info->fs_devices; 3693 struct list_head *cur; 3694 struct map_lookup *map = NULL; 3695 struct extent_map_tree *em_tree; 3696 struct extent_map *em; 3697 struct btrfs_device_info *devices_info = NULL; 3698 u64 total_avail; 3699 int num_stripes; /* total number of stripes to allocate */ 3700 int data_stripes; /* number of stripes that count for 3701 block group size */ 3702 int sub_stripes; /* sub_stripes info for map */ 3703 int dev_stripes; /* stripes per dev */ 3704 int devs_max; /* max devs to use */ 3705 int devs_min; /* min devs needed */ 3706 int devs_increment; /* ndevs has to be a multiple of this */ 3707 int ncopies; /* how many copies to data has */ 3708 int ret; 3709 u64 max_stripe_size; 3710 u64 max_chunk_size; 3711 u64 stripe_size; 3712 u64 num_bytes; 3713 u64 raid_stripe_len = BTRFS_STRIPE_LEN; 3714 int ndevs; 3715 int i; 3716 int j; 3717 int index; 3718 3719 BUG_ON(!alloc_profile_is_valid(type, 0)); 3720 3721 if (list_empty(&fs_devices->alloc_list)) 3722 return -ENOSPC; 3723 3724 index = __get_raid_index(type); 3725 3726 sub_stripes = btrfs_raid_array[index].sub_stripes; 3727 dev_stripes = btrfs_raid_array[index].dev_stripes; 3728 devs_max = btrfs_raid_array[index].devs_max; 3729 devs_min = btrfs_raid_array[index].devs_min; 3730 devs_increment = btrfs_raid_array[index].devs_increment; 3731 ncopies = btrfs_raid_array[index].ncopies; 3732 3733 if (type & BTRFS_BLOCK_GROUP_DATA) { 3734 max_stripe_size = 1024 * 1024 * 1024; 3735 max_chunk_size = 10 * max_stripe_size; 3736 } else if (type & BTRFS_BLOCK_GROUP_METADATA) { 3737 /* for larger filesystems, use larger metadata chunks */ 3738 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024) 3739 max_stripe_size = 1024 * 1024 * 1024; 3740 else 3741 max_stripe_size = 256 * 1024 * 1024; 3742 max_chunk_size = max_stripe_size; 3743 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { 3744 max_stripe_size = 32 * 1024 * 1024; 3745 max_chunk_size = 2 * max_stripe_size; 3746 } else { 3747 printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n", 3748 type); 3749 BUG_ON(1); 3750 } 3751 3752 /* we don't want a chunk larger than 10% of writeable space */ 3753 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1), 3754 max_chunk_size); 3755 3756 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices, 3757 GFP_NOFS); 3758 if (!devices_info) 3759 return -ENOMEM; 3760 3761 cur = fs_devices->alloc_list.next; 3762 3763 /* 3764 * in the first pass through the devices list, we gather information 3765 * about the available holes on each device. 3766 */ 3767 ndevs = 0; 3768 while (cur != &fs_devices->alloc_list) { 3769 struct btrfs_device *device; 3770 u64 max_avail; 3771 u64 dev_offset; 3772 3773 device = list_entry(cur, struct btrfs_device, dev_alloc_list); 3774 3775 cur = cur->next; 3776 3777 if (!device->writeable) { 3778 WARN(1, KERN_ERR 3779 "btrfs: read-only device in alloc_list\n"); 3780 continue; 3781 } 3782 3783 if (!device->in_fs_metadata || 3784 device->is_tgtdev_for_dev_replace) 3785 continue; 3786 3787 if (device->total_bytes > device->bytes_used) 3788 total_avail = device->total_bytes - device->bytes_used; 3789 else 3790 total_avail = 0; 3791 3792 /* If there is no space on this device, skip it. */ 3793 if (total_avail == 0) 3794 continue; 3795 3796 ret = find_free_dev_extent(device, 3797 max_stripe_size * dev_stripes, 3798 &dev_offset, &max_avail); 3799 if (ret && ret != -ENOSPC) 3800 goto error; 3801 3802 if (ret == 0) 3803 max_avail = max_stripe_size * dev_stripes; 3804 3805 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes) 3806 continue; 3807 3808 if (ndevs == fs_devices->rw_devices) { 3809 WARN(1, "%s: found more than %llu devices\n", 3810 __func__, fs_devices->rw_devices); 3811 break; 3812 } 3813 devices_info[ndevs].dev_offset = dev_offset; 3814 devices_info[ndevs].max_avail = max_avail; 3815 devices_info[ndevs].total_avail = total_avail; 3816 devices_info[ndevs].dev = device; 3817 ++ndevs; 3818 } 3819 3820 /* 3821 * now sort the devices by hole size / available space 3822 */ 3823 sort(devices_info, ndevs, sizeof(struct btrfs_device_info), 3824 btrfs_cmp_device_info, NULL); 3825 3826 /* round down to number of usable stripes */ 3827 ndevs -= ndevs % devs_increment; 3828 3829 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) { 3830 ret = -ENOSPC; 3831 goto error; 3832 } 3833 3834 if (devs_max && ndevs > devs_max) 3835 ndevs = devs_max; 3836 /* 3837 * the primary goal is to maximize the number of stripes, so use as many 3838 * devices as possible, even if the stripes are not maximum sized. 3839 */ 3840 stripe_size = devices_info[ndevs-1].max_avail; 3841 num_stripes = ndevs * dev_stripes; 3842 3843 /* 3844 * this will have to be fixed for RAID1 and RAID10 over 3845 * more drives 3846 */ 3847 data_stripes = num_stripes / ncopies; 3848 3849 if (type & BTRFS_BLOCK_GROUP_RAID5) { 3850 raid_stripe_len = find_raid56_stripe_len(ndevs - 1, 3851 btrfs_super_stripesize(info->super_copy)); 3852 data_stripes = num_stripes - 1; 3853 } 3854 if (type & BTRFS_BLOCK_GROUP_RAID6) { 3855 raid_stripe_len = find_raid56_stripe_len(ndevs - 2, 3856 btrfs_super_stripesize(info->super_copy)); 3857 data_stripes = num_stripes - 2; 3858 } 3859 3860 /* 3861 * Use the number of data stripes to figure out how big this chunk 3862 * is really going to be in terms of logical address space, 3863 * and compare that answer with the max chunk size 3864 */ 3865 if (stripe_size * data_stripes > max_chunk_size) { 3866 u64 mask = (1ULL << 24) - 1; 3867 stripe_size = max_chunk_size; 3868 do_div(stripe_size, data_stripes); 3869 3870 /* bump the answer up to a 16MB boundary */ 3871 stripe_size = (stripe_size + mask) & ~mask; 3872 3873 /* but don't go higher than the limits we found 3874 * while searching for free extents 3875 */ 3876 if (stripe_size > devices_info[ndevs-1].max_avail) 3877 stripe_size = devices_info[ndevs-1].max_avail; 3878 } 3879 3880 do_div(stripe_size, dev_stripes); 3881 3882 /* align to BTRFS_STRIPE_LEN */ 3883 do_div(stripe_size, raid_stripe_len); 3884 stripe_size *= raid_stripe_len; 3885 3886 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 3887 if (!map) { 3888 ret = -ENOMEM; 3889 goto error; 3890 } 3891 map->num_stripes = num_stripes; 3892 3893 for (i = 0; i < ndevs; ++i) { 3894 for (j = 0; j < dev_stripes; ++j) { 3895 int s = i * dev_stripes + j; 3896 map->stripes[s].dev = devices_info[i].dev; 3897 map->stripes[s].physical = devices_info[i].dev_offset + 3898 j * stripe_size; 3899 } 3900 } 3901 map->sector_size = extent_root->sectorsize; 3902 map->stripe_len = raid_stripe_len; 3903 map->io_align = raid_stripe_len; 3904 map->io_width = raid_stripe_len; 3905 map->type = type; 3906 map->sub_stripes = sub_stripes; 3907 3908 *map_ret = map; 3909 num_bytes = stripe_size * data_stripes; 3910 3911 *stripe_size_out = stripe_size; 3912 *num_bytes_out = num_bytes; 3913 3914 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes); 3915 3916 em = alloc_extent_map(); 3917 if (!em) { 3918 ret = -ENOMEM; 3919 goto error; 3920 } 3921 em->bdev = (struct block_device *)map; 3922 em->start = start; 3923 em->len = num_bytes; 3924 em->block_start = 0; 3925 em->block_len = em->len; 3926 3927 em_tree = &extent_root->fs_info->mapping_tree.map_tree; 3928 write_lock(&em_tree->lock); 3929 ret = add_extent_mapping(em_tree, em); 3930 write_unlock(&em_tree->lock); 3931 if (ret) { 3932 free_extent_map(em); 3933 goto error; 3934 } 3935 3936 for (i = 0; i < map->num_stripes; ++i) { 3937 struct btrfs_device *device; 3938 u64 dev_offset; 3939 3940 device = map->stripes[i].dev; 3941 dev_offset = map->stripes[i].physical; 3942 3943 ret = btrfs_alloc_dev_extent(trans, device, 3944 info->chunk_root->root_key.objectid, 3945 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3946 start, dev_offset, stripe_size); 3947 if (ret) 3948 goto error_dev_extent; 3949 } 3950 3951 ret = btrfs_make_block_group(trans, extent_root, 0, type, 3952 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3953 start, num_bytes); 3954 if (ret) { 3955 i = map->num_stripes - 1; 3956 goto error_dev_extent; 3957 } 3958 3959 free_extent_map(em); 3960 check_raid56_incompat_flag(extent_root->fs_info, type); 3961 3962 kfree(devices_info); 3963 return 0; 3964 3965 error_dev_extent: 3966 for (; i >= 0; i--) { 3967 struct btrfs_device *device; 3968 int err; 3969 3970 device = map->stripes[i].dev; 3971 err = btrfs_free_dev_extent(trans, device, start); 3972 if (err) { 3973 btrfs_abort_transaction(trans, extent_root, err); 3974 break; 3975 } 3976 } 3977 write_lock(&em_tree->lock); 3978 remove_extent_mapping(em_tree, em); 3979 write_unlock(&em_tree->lock); 3980 3981 /* One for our allocation */ 3982 free_extent_map(em); 3983 /* One for the tree reference */ 3984 free_extent_map(em); 3985 error: 3986 kfree(map); 3987 kfree(devices_info); 3988 return ret; 3989 } 3990 3991 static int __finish_chunk_alloc(struct btrfs_trans_handle *trans, 3992 struct btrfs_root *extent_root, 3993 struct map_lookup *map, u64 chunk_offset, 3994 u64 chunk_size, u64 stripe_size) 3995 { 3996 u64 dev_offset; 3997 struct btrfs_key key; 3998 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 3999 struct btrfs_device *device; 4000 struct btrfs_chunk *chunk; 4001 struct btrfs_stripe *stripe; 4002 size_t item_size = btrfs_chunk_item_size(map->num_stripes); 4003 int index = 0; 4004 int ret; 4005 4006 chunk = kzalloc(item_size, GFP_NOFS); 4007 if (!chunk) 4008 return -ENOMEM; 4009 4010 index = 0; 4011 while (index < map->num_stripes) { 4012 device = map->stripes[index].dev; 4013 device->bytes_used += stripe_size; 4014 ret = btrfs_update_device(trans, device); 4015 if (ret) 4016 goto out_free; 4017 index++; 4018 } 4019 4020 spin_lock(&extent_root->fs_info->free_chunk_lock); 4021 extent_root->fs_info->free_chunk_space -= (stripe_size * 4022 map->num_stripes); 4023 spin_unlock(&extent_root->fs_info->free_chunk_lock); 4024 4025 index = 0; 4026 stripe = &chunk->stripe; 4027 while (index < map->num_stripes) { 4028 device = map->stripes[index].dev; 4029 dev_offset = map->stripes[index].physical; 4030 4031 btrfs_set_stack_stripe_devid(stripe, device->devid); 4032 btrfs_set_stack_stripe_offset(stripe, dev_offset); 4033 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); 4034 stripe++; 4035 index++; 4036 } 4037 4038 btrfs_set_stack_chunk_length(chunk, chunk_size); 4039 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); 4040 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); 4041 btrfs_set_stack_chunk_type(chunk, map->type); 4042 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); 4043 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); 4044 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); 4045 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); 4046 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); 4047 4048 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 4049 key.type = BTRFS_CHUNK_ITEM_KEY; 4050 key.offset = chunk_offset; 4051 4052 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); 4053 4054 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 4055 /* 4056 * TODO: Cleanup of inserted chunk root in case of 4057 * failure. 4058 */ 4059 ret = btrfs_add_system_chunk(chunk_root, &key, chunk, 4060 item_size); 4061 } 4062 4063 out_free: 4064 kfree(chunk); 4065 return ret; 4066 } 4067 4068 /* 4069 * Chunk allocation falls into two parts. The first part does works 4070 * that make the new allocated chunk useable, but not do any operation 4071 * that modifies the chunk tree. The second part does the works that 4072 * require modifying the chunk tree. This division is important for the 4073 * bootstrap process of adding storage to a seed btrfs. 4074 */ 4075 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 4076 struct btrfs_root *extent_root, u64 type) 4077 { 4078 u64 chunk_offset; 4079 u64 chunk_size; 4080 u64 stripe_size; 4081 struct map_lookup *map; 4082 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 4083 int ret; 4084 4085 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, 4086 &chunk_offset); 4087 if (ret) 4088 return ret; 4089 4090 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, 4091 &stripe_size, chunk_offset, type); 4092 if (ret) 4093 return ret; 4094 4095 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, 4096 chunk_size, stripe_size); 4097 if (ret) 4098 return ret; 4099 return 0; 4100 } 4101 4102 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans, 4103 struct btrfs_root *root, 4104 struct btrfs_device *device) 4105 { 4106 u64 chunk_offset; 4107 u64 sys_chunk_offset; 4108 u64 chunk_size; 4109 u64 sys_chunk_size; 4110 u64 stripe_size; 4111 u64 sys_stripe_size; 4112 u64 alloc_profile; 4113 struct map_lookup *map; 4114 struct map_lookup *sys_map; 4115 struct btrfs_fs_info *fs_info = root->fs_info; 4116 struct btrfs_root *extent_root = fs_info->extent_root; 4117 int ret; 4118 4119 ret = find_next_chunk(fs_info->chunk_root, 4120 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset); 4121 if (ret) 4122 return ret; 4123 4124 alloc_profile = btrfs_get_alloc_profile(extent_root, 0); 4125 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, 4126 &stripe_size, chunk_offset, alloc_profile); 4127 if (ret) 4128 return ret; 4129 4130 sys_chunk_offset = chunk_offset + chunk_size; 4131 4132 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0); 4133 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map, 4134 &sys_chunk_size, &sys_stripe_size, 4135 sys_chunk_offset, alloc_profile); 4136 if (ret) { 4137 btrfs_abort_transaction(trans, root, ret); 4138 goto out; 4139 } 4140 4141 ret = btrfs_add_device(trans, fs_info->chunk_root, device); 4142 if (ret) { 4143 btrfs_abort_transaction(trans, root, ret); 4144 goto out; 4145 } 4146 4147 /* 4148 * Modifying chunk tree needs allocating new blocks from both 4149 * system block group and metadata block group. So we only can 4150 * do operations require modifying the chunk tree after both 4151 * block groups were created. 4152 */ 4153 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, 4154 chunk_size, stripe_size); 4155 if (ret) { 4156 btrfs_abort_transaction(trans, root, ret); 4157 goto out; 4158 } 4159 4160 ret = __finish_chunk_alloc(trans, extent_root, sys_map, 4161 sys_chunk_offset, sys_chunk_size, 4162 sys_stripe_size); 4163 if (ret) 4164 btrfs_abort_transaction(trans, root, ret); 4165 4166 out: 4167 4168 return ret; 4169 } 4170 4171 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) 4172 { 4173 struct extent_map *em; 4174 struct map_lookup *map; 4175 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 4176 int readonly = 0; 4177 int i; 4178 4179 read_lock(&map_tree->map_tree.lock); 4180 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); 4181 read_unlock(&map_tree->map_tree.lock); 4182 if (!em) 4183 return 1; 4184 4185 if (btrfs_test_opt(root, DEGRADED)) { 4186 free_extent_map(em); 4187 return 0; 4188 } 4189 4190 map = (struct map_lookup *)em->bdev; 4191 for (i = 0; i < map->num_stripes; i++) { 4192 if (!map->stripes[i].dev->writeable) { 4193 readonly = 1; 4194 break; 4195 } 4196 } 4197 free_extent_map(em); 4198 return readonly; 4199 } 4200 4201 void btrfs_mapping_init(struct btrfs_mapping_tree *tree) 4202 { 4203 extent_map_tree_init(&tree->map_tree); 4204 } 4205 4206 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree) 4207 { 4208 struct extent_map *em; 4209 4210 while (1) { 4211 write_lock(&tree->map_tree.lock); 4212 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1); 4213 if (em) 4214 remove_extent_mapping(&tree->map_tree, em); 4215 write_unlock(&tree->map_tree.lock); 4216 if (!em) 4217 break; 4218 kfree(em->bdev); 4219 /* once for us */ 4220 free_extent_map(em); 4221 /* once for the tree */ 4222 free_extent_map(em); 4223 } 4224 } 4225 4226 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) 4227 { 4228 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4229 struct extent_map *em; 4230 struct map_lookup *map; 4231 struct extent_map_tree *em_tree = &map_tree->map_tree; 4232 int ret; 4233 4234 read_lock(&em_tree->lock); 4235 em = lookup_extent_mapping(em_tree, logical, len); 4236 read_unlock(&em_tree->lock); 4237 BUG_ON(!em); 4238 4239 BUG_ON(em->start > logical || em->start + em->len < logical); 4240 map = (struct map_lookup *)em->bdev; 4241 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1)) 4242 ret = map->num_stripes; 4243 else if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4244 ret = map->sub_stripes; 4245 else if (map->type & BTRFS_BLOCK_GROUP_RAID5) 4246 ret = 2; 4247 else if (map->type & BTRFS_BLOCK_GROUP_RAID6) 4248 ret = 3; 4249 else 4250 ret = 1; 4251 free_extent_map(em); 4252 4253 btrfs_dev_replace_lock(&fs_info->dev_replace); 4254 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) 4255 ret++; 4256 btrfs_dev_replace_unlock(&fs_info->dev_replace); 4257 4258 return ret; 4259 } 4260 4261 unsigned long btrfs_full_stripe_len(struct btrfs_root *root, 4262 struct btrfs_mapping_tree *map_tree, 4263 u64 logical) 4264 { 4265 struct extent_map *em; 4266 struct map_lookup *map; 4267 struct extent_map_tree *em_tree = &map_tree->map_tree; 4268 unsigned long len = root->sectorsize; 4269 4270 read_lock(&em_tree->lock); 4271 em = lookup_extent_mapping(em_tree, logical, len); 4272 read_unlock(&em_tree->lock); 4273 BUG_ON(!em); 4274 4275 BUG_ON(em->start > logical || em->start + em->len < logical); 4276 map = (struct map_lookup *)em->bdev; 4277 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4278 BTRFS_BLOCK_GROUP_RAID6)) { 4279 len = map->stripe_len * nr_data_stripes(map); 4280 } 4281 free_extent_map(em); 4282 return len; 4283 } 4284 4285 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree, 4286 u64 logical, u64 len, int mirror_num) 4287 { 4288 struct extent_map *em; 4289 struct map_lookup *map; 4290 struct extent_map_tree *em_tree = &map_tree->map_tree; 4291 int ret = 0; 4292 4293 read_lock(&em_tree->lock); 4294 em = lookup_extent_mapping(em_tree, logical, len); 4295 read_unlock(&em_tree->lock); 4296 BUG_ON(!em); 4297 4298 BUG_ON(em->start > logical || em->start + em->len < logical); 4299 map = (struct map_lookup *)em->bdev; 4300 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4301 BTRFS_BLOCK_GROUP_RAID6)) 4302 ret = 1; 4303 free_extent_map(em); 4304 return ret; 4305 } 4306 4307 static int find_live_mirror(struct btrfs_fs_info *fs_info, 4308 struct map_lookup *map, int first, int num, 4309 int optimal, int dev_replace_is_ongoing) 4310 { 4311 int i; 4312 int tolerance; 4313 struct btrfs_device *srcdev; 4314 4315 if (dev_replace_is_ongoing && 4316 fs_info->dev_replace.cont_reading_from_srcdev_mode == 4317 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID) 4318 srcdev = fs_info->dev_replace.srcdev; 4319 else 4320 srcdev = NULL; 4321 4322 /* 4323 * try to avoid the drive that is the source drive for a 4324 * dev-replace procedure, only choose it if no other non-missing 4325 * mirror is available 4326 */ 4327 for (tolerance = 0; tolerance < 2; tolerance++) { 4328 if (map->stripes[optimal].dev->bdev && 4329 (tolerance || map->stripes[optimal].dev != srcdev)) 4330 return optimal; 4331 for (i = first; i < first + num; i++) { 4332 if (map->stripes[i].dev->bdev && 4333 (tolerance || map->stripes[i].dev != srcdev)) 4334 return i; 4335 } 4336 } 4337 4338 /* we couldn't find one that doesn't fail. Just return something 4339 * and the io error handling code will clean up eventually 4340 */ 4341 return optimal; 4342 } 4343 4344 static inline int parity_smaller(u64 a, u64 b) 4345 { 4346 return a > b; 4347 } 4348 4349 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */ 4350 static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map) 4351 { 4352 struct btrfs_bio_stripe s; 4353 int i; 4354 u64 l; 4355 int again = 1; 4356 4357 while (again) { 4358 again = 0; 4359 for (i = 0; i < bbio->num_stripes - 1; i++) { 4360 if (parity_smaller(raid_map[i], raid_map[i+1])) { 4361 s = bbio->stripes[i]; 4362 l = raid_map[i]; 4363 bbio->stripes[i] = bbio->stripes[i+1]; 4364 raid_map[i] = raid_map[i+1]; 4365 bbio->stripes[i+1] = s; 4366 raid_map[i+1] = l; 4367 again = 1; 4368 } 4369 } 4370 } 4371 } 4372 4373 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4374 u64 logical, u64 *length, 4375 struct btrfs_bio **bbio_ret, 4376 int mirror_num, u64 **raid_map_ret) 4377 { 4378 struct extent_map *em; 4379 struct map_lookup *map; 4380 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4381 struct extent_map_tree *em_tree = &map_tree->map_tree; 4382 u64 offset; 4383 u64 stripe_offset; 4384 u64 stripe_end_offset; 4385 u64 stripe_nr; 4386 u64 stripe_nr_orig; 4387 u64 stripe_nr_end; 4388 u64 stripe_len; 4389 u64 *raid_map = NULL; 4390 int stripe_index; 4391 int i; 4392 int ret = 0; 4393 int num_stripes; 4394 int max_errors = 0; 4395 struct btrfs_bio *bbio = NULL; 4396 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 4397 int dev_replace_is_ongoing = 0; 4398 int num_alloc_stripes; 4399 int patch_the_first_stripe_for_dev_replace = 0; 4400 u64 physical_to_patch_in_first_stripe = 0; 4401 u64 raid56_full_stripe_start = (u64)-1; 4402 4403 read_lock(&em_tree->lock); 4404 em = lookup_extent_mapping(em_tree, logical, *length); 4405 read_unlock(&em_tree->lock); 4406 4407 if (!em) { 4408 printk(KERN_CRIT "btrfs: unable to find logical %llu len %llu\n", 4409 (unsigned long long)logical, 4410 (unsigned long long)*length); 4411 BUG(); 4412 } 4413 4414 BUG_ON(em->start > logical || em->start + em->len < logical); 4415 map = (struct map_lookup *)em->bdev; 4416 offset = logical - em->start; 4417 4418 if (mirror_num > map->num_stripes) 4419 mirror_num = 0; 4420 4421 stripe_len = map->stripe_len; 4422 stripe_nr = offset; 4423 /* 4424 * stripe_nr counts the total number of stripes we have to stride 4425 * to get to this block 4426 */ 4427 do_div(stripe_nr, stripe_len); 4428 4429 stripe_offset = stripe_nr * stripe_len; 4430 BUG_ON(offset < stripe_offset); 4431 4432 /* stripe_offset is the offset of this block in its stripe*/ 4433 stripe_offset = offset - stripe_offset; 4434 4435 /* if we're here for raid56, we need to know the stripe aligned start */ 4436 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { 4437 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map); 4438 raid56_full_stripe_start = offset; 4439 4440 /* allow a write of a full stripe, but make sure we don't 4441 * allow straddling of stripes 4442 */ 4443 do_div(raid56_full_stripe_start, full_stripe_len); 4444 raid56_full_stripe_start *= full_stripe_len; 4445 } 4446 4447 if (rw & REQ_DISCARD) { 4448 /* we don't discard raid56 yet */ 4449 if (map->type & 4450 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { 4451 ret = -EOPNOTSUPP; 4452 goto out; 4453 } 4454 *length = min_t(u64, em->len - offset, *length); 4455 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { 4456 u64 max_len; 4457 /* For writes to RAID[56], allow a full stripeset across all disks. 4458 For other RAID types and for RAID[56] reads, just allow a single 4459 stripe (on a single disk). */ 4460 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6) && 4461 (rw & REQ_WRITE)) { 4462 max_len = stripe_len * nr_data_stripes(map) - 4463 (offset - raid56_full_stripe_start); 4464 } else { 4465 /* we limit the length of each bio to what fits in a stripe */ 4466 max_len = stripe_len - stripe_offset; 4467 } 4468 *length = min_t(u64, em->len - offset, max_len); 4469 } else { 4470 *length = em->len - offset; 4471 } 4472 4473 /* This is for when we're called from btrfs_merge_bio_hook() and all 4474 it cares about is the length */ 4475 if (!bbio_ret) 4476 goto out; 4477 4478 btrfs_dev_replace_lock(dev_replace); 4479 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace); 4480 if (!dev_replace_is_ongoing) 4481 btrfs_dev_replace_unlock(dev_replace); 4482 4483 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 && 4484 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) && 4485 dev_replace->tgtdev != NULL) { 4486 /* 4487 * in dev-replace case, for repair case (that's the only 4488 * case where the mirror is selected explicitly when 4489 * calling btrfs_map_block), blocks left of the left cursor 4490 * can also be read from the target drive. 4491 * For REQ_GET_READ_MIRRORS, the target drive is added as 4492 * the last one to the array of stripes. For READ, it also 4493 * needs to be supported using the same mirror number. 4494 * If the requested block is not left of the left cursor, 4495 * EIO is returned. This can happen because btrfs_num_copies() 4496 * returns one more in the dev-replace case. 4497 */ 4498 u64 tmp_length = *length; 4499 struct btrfs_bio *tmp_bbio = NULL; 4500 int tmp_num_stripes; 4501 u64 srcdev_devid = dev_replace->srcdev->devid; 4502 int index_srcdev = 0; 4503 int found = 0; 4504 u64 physical_of_found = 0; 4505 4506 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, 4507 logical, &tmp_length, &tmp_bbio, 0, NULL); 4508 if (ret) { 4509 WARN_ON(tmp_bbio != NULL); 4510 goto out; 4511 } 4512 4513 tmp_num_stripes = tmp_bbio->num_stripes; 4514 if (mirror_num > tmp_num_stripes) { 4515 /* 4516 * REQ_GET_READ_MIRRORS does not contain this 4517 * mirror, that means that the requested area 4518 * is not left of the left cursor 4519 */ 4520 ret = -EIO; 4521 kfree(tmp_bbio); 4522 goto out; 4523 } 4524 4525 /* 4526 * process the rest of the function using the mirror_num 4527 * of the source drive. Therefore look it up first. 4528 * At the end, patch the device pointer to the one of the 4529 * target drive. 4530 */ 4531 for (i = 0; i < tmp_num_stripes; i++) { 4532 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) { 4533 /* 4534 * In case of DUP, in order to keep it 4535 * simple, only add the mirror with the 4536 * lowest physical address 4537 */ 4538 if (found && 4539 physical_of_found <= 4540 tmp_bbio->stripes[i].physical) 4541 continue; 4542 index_srcdev = i; 4543 found = 1; 4544 physical_of_found = 4545 tmp_bbio->stripes[i].physical; 4546 } 4547 } 4548 4549 if (found) { 4550 mirror_num = index_srcdev + 1; 4551 patch_the_first_stripe_for_dev_replace = 1; 4552 physical_to_patch_in_first_stripe = physical_of_found; 4553 } else { 4554 WARN_ON(1); 4555 ret = -EIO; 4556 kfree(tmp_bbio); 4557 goto out; 4558 } 4559 4560 kfree(tmp_bbio); 4561 } else if (mirror_num > map->num_stripes) { 4562 mirror_num = 0; 4563 } 4564 4565 num_stripes = 1; 4566 stripe_index = 0; 4567 stripe_nr_orig = stripe_nr; 4568 stripe_nr_end = ALIGN(offset + *length, map->stripe_len); 4569 do_div(stripe_nr_end, map->stripe_len); 4570 stripe_end_offset = stripe_nr_end * map->stripe_len - 4571 (offset + *length); 4572 4573 if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4574 if (rw & REQ_DISCARD) 4575 num_stripes = min_t(u64, map->num_stripes, 4576 stripe_nr_end - stripe_nr_orig); 4577 stripe_index = do_div(stripe_nr, map->num_stripes); 4578 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { 4579 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) 4580 num_stripes = map->num_stripes; 4581 else if (mirror_num) 4582 stripe_index = mirror_num - 1; 4583 else { 4584 stripe_index = find_live_mirror(fs_info, map, 0, 4585 map->num_stripes, 4586 current->pid % map->num_stripes, 4587 dev_replace_is_ongoing); 4588 mirror_num = stripe_index + 1; 4589 } 4590 4591 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { 4592 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) { 4593 num_stripes = map->num_stripes; 4594 } else if (mirror_num) { 4595 stripe_index = mirror_num - 1; 4596 } else { 4597 mirror_num = 1; 4598 } 4599 4600 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4601 int factor = map->num_stripes / map->sub_stripes; 4602 4603 stripe_index = do_div(stripe_nr, factor); 4604 stripe_index *= map->sub_stripes; 4605 4606 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) 4607 num_stripes = map->sub_stripes; 4608 else if (rw & REQ_DISCARD) 4609 num_stripes = min_t(u64, map->sub_stripes * 4610 (stripe_nr_end - stripe_nr_orig), 4611 map->num_stripes); 4612 else if (mirror_num) 4613 stripe_index += mirror_num - 1; 4614 else { 4615 int old_stripe_index = stripe_index; 4616 stripe_index = find_live_mirror(fs_info, map, 4617 stripe_index, 4618 map->sub_stripes, stripe_index + 4619 current->pid % map->sub_stripes, 4620 dev_replace_is_ongoing); 4621 mirror_num = stripe_index - old_stripe_index + 1; 4622 } 4623 4624 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4625 BTRFS_BLOCK_GROUP_RAID6)) { 4626 u64 tmp; 4627 4628 if (bbio_ret && ((rw & REQ_WRITE) || mirror_num > 1) 4629 && raid_map_ret) { 4630 int i, rot; 4631 4632 /* push stripe_nr back to the start of the full stripe */ 4633 stripe_nr = raid56_full_stripe_start; 4634 do_div(stripe_nr, stripe_len); 4635 4636 stripe_index = do_div(stripe_nr, nr_data_stripes(map)); 4637 4638 /* RAID[56] write or recovery. Return all stripes */ 4639 num_stripes = map->num_stripes; 4640 max_errors = nr_parity_stripes(map); 4641 4642 raid_map = kmalloc(sizeof(u64) * num_stripes, 4643 GFP_NOFS); 4644 if (!raid_map) { 4645 ret = -ENOMEM; 4646 goto out; 4647 } 4648 4649 /* Work out the disk rotation on this stripe-set */ 4650 tmp = stripe_nr; 4651 rot = do_div(tmp, num_stripes); 4652 4653 /* Fill in the logical address of each stripe */ 4654 tmp = stripe_nr * nr_data_stripes(map); 4655 for (i = 0; i < nr_data_stripes(map); i++) 4656 raid_map[(i+rot) % num_stripes] = 4657 em->start + (tmp + i) * map->stripe_len; 4658 4659 raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE; 4660 if (map->type & BTRFS_BLOCK_GROUP_RAID6) 4661 raid_map[(i+rot+1) % num_stripes] = 4662 RAID6_Q_STRIPE; 4663 4664 *length = map->stripe_len; 4665 stripe_index = 0; 4666 stripe_offset = 0; 4667 } else { 4668 /* 4669 * Mirror #0 or #1 means the original data block. 4670 * Mirror #2 is RAID5 parity block. 4671 * Mirror #3 is RAID6 Q block. 4672 */ 4673 stripe_index = do_div(stripe_nr, nr_data_stripes(map)); 4674 if (mirror_num > 1) 4675 stripe_index = nr_data_stripes(map) + 4676 mirror_num - 2; 4677 4678 /* We distribute the parity blocks across stripes */ 4679 tmp = stripe_nr + stripe_index; 4680 stripe_index = do_div(tmp, map->num_stripes); 4681 } 4682 } else { 4683 /* 4684 * after this do_div call, stripe_nr is the number of stripes 4685 * on this device we have to walk to find the data, and 4686 * stripe_index is the number of our device in the stripe array 4687 */ 4688 stripe_index = do_div(stripe_nr, map->num_stripes); 4689 mirror_num = stripe_index + 1; 4690 } 4691 BUG_ON(stripe_index >= map->num_stripes); 4692 4693 num_alloc_stripes = num_stripes; 4694 if (dev_replace_is_ongoing) { 4695 if (rw & (REQ_WRITE | REQ_DISCARD)) 4696 num_alloc_stripes <<= 1; 4697 if (rw & REQ_GET_READ_MIRRORS) 4698 num_alloc_stripes++; 4699 } 4700 bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS); 4701 if (!bbio) { 4702 ret = -ENOMEM; 4703 goto out; 4704 } 4705 atomic_set(&bbio->error, 0); 4706 4707 if (rw & REQ_DISCARD) { 4708 int factor = 0; 4709 int sub_stripes = 0; 4710 u64 stripes_per_dev = 0; 4711 u32 remaining_stripes = 0; 4712 u32 last_stripe = 0; 4713 4714 if (map->type & 4715 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { 4716 if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4717 sub_stripes = 1; 4718 else 4719 sub_stripes = map->sub_stripes; 4720 4721 factor = map->num_stripes / sub_stripes; 4722 stripes_per_dev = div_u64_rem(stripe_nr_end - 4723 stripe_nr_orig, 4724 factor, 4725 &remaining_stripes); 4726 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe); 4727 last_stripe *= sub_stripes; 4728 } 4729 4730 for (i = 0; i < num_stripes; i++) { 4731 bbio->stripes[i].physical = 4732 map->stripes[stripe_index].physical + 4733 stripe_offset + stripe_nr * map->stripe_len; 4734 bbio->stripes[i].dev = map->stripes[stripe_index].dev; 4735 4736 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | 4737 BTRFS_BLOCK_GROUP_RAID10)) { 4738 bbio->stripes[i].length = stripes_per_dev * 4739 map->stripe_len; 4740 4741 if (i / sub_stripes < remaining_stripes) 4742 bbio->stripes[i].length += 4743 map->stripe_len; 4744 4745 /* 4746 * Special for the first stripe and 4747 * the last stripe: 4748 * 4749 * |-------|...|-------| 4750 * |----------| 4751 * off end_off 4752 */ 4753 if (i < sub_stripes) 4754 bbio->stripes[i].length -= 4755 stripe_offset; 4756 4757 if (stripe_index >= last_stripe && 4758 stripe_index <= (last_stripe + 4759 sub_stripes - 1)) 4760 bbio->stripes[i].length -= 4761 stripe_end_offset; 4762 4763 if (i == sub_stripes - 1) 4764 stripe_offset = 0; 4765 } else 4766 bbio->stripes[i].length = *length; 4767 4768 stripe_index++; 4769 if (stripe_index == map->num_stripes) { 4770 /* This could only happen for RAID0/10 */ 4771 stripe_index = 0; 4772 stripe_nr++; 4773 } 4774 } 4775 } else { 4776 for (i = 0; i < num_stripes; i++) { 4777 bbio->stripes[i].physical = 4778 map->stripes[stripe_index].physical + 4779 stripe_offset + 4780 stripe_nr * map->stripe_len; 4781 bbio->stripes[i].dev = 4782 map->stripes[stripe_index].dev; 4783 stripe_index++; 4784 } 4785 } 4786 4787 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) { 4788 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | 4789 BTRFS_BLOCK_GROUP_RAID10 | 4790 BTRFS_BLOCK_GROUP_RAID5 | 4791 BTRFS_BLOCK_GROUP_DUP)) { 4792 max_errors = 1; 4793 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) { 4794 max_errors = 2; 4795 } 4796 } 4797 4798 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) && 4799 dev_replace->tgtdev != NULL) { 4800 int index_where_to_add; 4801 u64 srcdev_devid = dev_replace->srcdev->devid; 4802 4803 /* 4804 * duplicate the write operations while the dev replace 4805 * procedure is running. Since the copying of the old disk 4806 * to the new disk takes place at run time while the 4807 * filesystem is mounted writable, the regular write 4808 * operations to the old disk have to be duplicated to go 4809 * to the new disk as well. 4810 * Note that device->missing is handled by the caller, and 4811 * that the write to the old disk is already set up in the 4812 * stripes array. 4813 */ 4814 index_where_to_add = num_stripes; 4815 for (i = 0; i < num_stripes; i++) { 4816 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4817 /* write to new disk, too */ 4818 struct btrfs_bio_stripe *new = 4819 bbio->stripes + index_where_to_add; 4820 struct btrfs_bio_stripe *old = 4821 bbio->stripes + i; 4822 4823 new->physical = old->physical; 4824 new->length = old->length; 4825 new->dev = dev_replace->tgtdev; 4826 index_where_to_add++; 4827 max_errors++; 4828 } 4829 } 4830 num_stripes = index_where_to_add; 4831 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) && 4832 dev_replace->tgtdev != NULL) { 4833 u64 srcdev_devid = dev_replace->srcdev->devid; 4834 int index_srcdev = 0; 4835 int found = 0; 4836 u64 physical_of_found = 0; 4837 4838 /* 4839 * During the dev-replace procedure, the target drive can 4840 * also be used to read data in case it is needed to repair 4841 * a corrupt block elsewhere. This is possible if the 4842 * requested area is left of the left cursor. In this area, 4843 * the target drive is a full copy of the source drive. 4844 */ 4845 for (i = 0; i < num_stripes; i++) { 4846 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4847 /* 4848 * In case of DUP, in order to keep it 4849 * simple, only add the mirror with the 4850 * lowest physical address 4851 */ 4852 if (found && 4853 physical_of_found <= 4854 bbio->stripes[i].physical) 4855 continue; 4856 index_srcdev = i; 4857 found = 1; 4858 physical_of_found = bbio->stripes[i].physical; 4859 } 4860 } 4861 if (found) { 4862 u64 length = map->stripe_len; 4863 4864 if (physical_of_found + length <= 4865 dev_replace->cursor_left) { 4866 struct btrfs_bio_stripe *tgtdev_stripe = 4867 bbio->stripes + num_stripes; 4868 4869 tgtdev_stripe->physical = physical_of_found; 4870 tgtdev_stripe->length = 4871 bbio->stripes[index_srcdev].length; 4872 tgtdev_stripe->dev = dev_replace->tgtdev; 4873 4874 num_stripes++; 4875 } 4876 } 4877 } 4878 4879 *bbio_ret = bbio; 4880 bbio->num_stripes = num_stripes; 4881 bbio->max_errors = max_errors; 4882 bbio->mirror_num = mirror_num; 4883 4884 /* 4885 * this is the case that REQ_READ && dev_replace_is_ongoing && 4886 * mirror_num == num_stripes + 1 && dev_replace target drive is 4887 * available as a mirror 4888 */ 4889 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) { 4890 WARN_ON(num_stripes > 1); 4891 bbio->stripes[0].dev = dev_replace->tgtdev; 4892 bbio->stripes[0].physical = physical_to_patch_in_first_stripe; 4893 bbio->mirror_num = map->num_stripes + 1; 4894 } 4895 if (raid_map) { 4896 sort_parity_stripes(bbio, raid_map); 4897 *raid_map_ret = raid_map; 4898 } 4899 out: 4900 if (dev_replace_is_ongoing) 4901 btrfs_dev_replace_unlock(dev_replace); 4902 free_extent_map(em); 4903 return ret; 4904 } 4905 4906 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4907 u64 logical, u64 *length, 4908 struct btrfs_bio **bbio_ret, int mirror_num) 4909 { 4910 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret, 4911 mirror_num, NULL); 4912 } 4913 4914 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, 4915 u64 chunk_start, u64 physical, u64 devid, 4916 u64 **logical, int *naddrs, int *stripe_len) 4917 { 4918 struct extent_map_tree *em_tree = &map_tree->map_tree; 4919 struct extent_map *em; 4920 struct map_lookup *map; 4921 u64 *buf; 4922 u64 bytenr; 4923 u64 length; 4924 u64 stripe_nr; 4925 u64 rmap_len; 4926 int i, j, nr = 0; 4927 4928 read_lock(&em_tree->lock); 4929 em = lookup_extent_mapping(em_tree, chunk_start, 1); 4930 read_unlock(&em_tree->lock); 4931 4932 BUG_ON(!em || em->start != chunk_start); 4933 map = (struct map_lookup *)em->bdev; 4934 4935 length = em->len; 4936 rmap_len = map->stripe_len; 4937 4938 if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4939 do_div(length, map->num_stripes / map->sub_stripes); 4940 else if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4941 do_div(length, map->num_stripes); 4942 else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4943 BTRFS_BLOCK_GROUP_RAID6)) { 4944 do_div(length, nr_data_stripes(map)); 4945 rmap_len = map->stripe_len * nr_data_stripes(map); 4946 } 4947 4948 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); 4949 BUG_ON(!buf); /* -ENOMEM */ 4950 4951 for (i = 0; i < map->num_stripes; i++) { 4952 if (devid && map->stripes[i].dev->devid != devid) 4953 continue; 4954 if (map->stripes[i].physical > physical || 4955 map->stripes[i].physical + length <= physical) 4956 continue; 4957 4958 stripe_nr = physical - map->stripes[i].physical; 4959 do_div(stripe_nr, map->stripe_len); 4960 4961 if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4962 stripe_nr = stripe_nr * map->num_stripes + i; 4963 do_div(stripe_nr, map->sub_stripes); 4964 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4965 stripe_nr = stripe_nr * map->num_stripes + i; 4966 } /* else if RAID[56], multiply by nr_data_stripes(). 4967 * Alternatively, just use rmap_len below instead of 4968 * map->stripe_len */ 4969 4970 bytenr = chunk_start + stripe_nr * rmap_len; 4971 WARN_ON(nr >= map->num_stripes); 4972 for (j = 0; j < nr; j++) { 4973 if (buf[j] == bytenr) 4974 break; 4975 } 4976 if (j == nr) { 4977 WARN_ON(nr >= map->num_stripes); 4978 buf[nr++] = bytenr; 4979 } 4980 } 4981 4982 *logical = buf; 4983 *naddrs = nr; 4984 *stripe_len = rmap_len; 4985 4986 free_extent_map(em); 4987 return 0; 4988 } 4989 4990 static void *merge_stripe_index_into_bio_private(void *bi_private, 4991 unsigned int stripe_index) 4992 { 4993 /* 4994 * with single, dup, RAID0, RAID1 and RAID10, stripe_index is 4995 * at most 1. 4996 * The alternative solution (instead of stealing bits from the 4997 * pointer) would be to allocate an intermediate structure 4998 * that contains the old private pointer plus the stripe_index. 4999 */ 5000 BUG_ON((((uintptr_t)bi_private) & 3) != 0); 5001 BUG_ON(stripe_index > 3); 5002 return (void *)(((uintptr_t)bi_private) | stripe_index); 5003 } 5004 5005 static struct btrfs_bio *extract_bbio_from_bio_private(void *bi_private) 5006 { 5007 return (struct btrfs_bio *)(((uintptr_t)bi_private) & ~((uintptr_t)3)); 5008 } 5009 5010 static unsigned int extract_stripe_index_from_bio_private(void *bi_private) 5011 { 5012 return (unsigned int)((uintptr_t)bi_private) & 3; 5013 } 5014 5015 static void btrfs_end_bio(struct bio *bio, int err) 5016 { 5017 struct btrfs_bio *bbio = extract_bbio_from_bio_private(bio->bi_private); 5018 int is_orig_bio = 0; 5019 5020 if (err) { 5021 atomic_inc(&bbio->error); 5022 if (err == -EIO || err == -EREMOTEIO) { 5023 unsigned int stripe_index = 5024 extract_stripe_index_from_bio_private( 5025 bio->bi_private); 5026 struct btrfs_device *dev; 5027 5028 BUG_ON(stripe_index >= bbio->num_stripes); 5029 dev = bbio->stripes[stripe_index].dev; 5030 if (dev->bdev) { 5031 if (bio->bi_rw & WRITE) 5032 btrfs_dev_stat_inc(dev, 5033 BTRFS_DEV_STAT_WRITE_ERRS); 5034 else 5035 btrfs_dev_stat_inc(dev, 5036 BTRFS_DEV_STAT_READ_ERRS); 5037 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH) 5038 btrfs_dev_stat_inc(dev, 5039 BTRFS_DEV_STAT_FLUSH_ERRS); 5040 btrfs_dev_stat_print_on_error(dev); 5041 } 5042 } 5043 } 5044 5045 if (bio == bbio->orig_bio) 5046 is_orig_bio = 1; 5047 5048 if (atomic_dec_and_test(&bbio->stripes_pending)) { 5049 if (!is_orig_bio) { 5050 bio_put(bio); 5051 bio = bbio->orig_bio; 5052 } 5053 bio->bi_private = bbio->private; 5054 bio->bi_end_io = bbio->end_io; 5055 bio->bi_bdev = (struct block_device *) 5056 (unsigned long)bbio->mirror_num; 5057 /* only send an error to the higher layers if it is 5058 * beyond the tolerance of the btrfs bio 5059 */ 5060 if (atomic_read(&bbio->error) > bbio->max_errors) { 5061 err = -EIO; 5062 } else { 5063 /* 5064 * this bio is actually up to date, we didn't 5065 * go over the max number of errors 5066 */ 5067 set_bit(BIO_UPTODATE, &bio->bi_flags); 5068 err = 0; 5069 } 5070 kfree(bbio); 5071 5072 bio_endio(bio, err); 5073 } else if (!is_orig_bio) { 5074 bio_put(bio); 5075 } 5076 } 5077 5078 struct async_sched { 5079 struct bio *bio; 5080 int rw; 5081 struct btrfs_fs_info *info; 5082 struct btrfs_work work; 5083 }; 5084 5085 /* 5086 * see run_scheduled_bios for a description of why bios are collected for 5087 * async submit. 5088 * 5089 * This will add one bio to the pending list for a device and make sure 5090 * the work struct is scheduled. 5091 */ 5092 noinline void btrfs_schedule_bio(struct btrfs_root *root, 5093 struct btrfs_device *device, 5094 int rw, struct bio *bio) 5095 { 5096 int should_queue = 1; 5097 struct btrfs_pending_bios *pending_bios; 5098 5099 if (device->missing || !device->bdev) { 5100 bio_endio(bio, -EIO); 5101 return; 5102 } 5103 5104 /* don't bother with additional async steps for reads, right now */ 5105 if (!(rw & REQ_WRITE)) { 5106 bio_get(bio); 5107 btrfsic_submit_bio(rw, bio); 5108 bio_put(bio); 5109 return; 5110 } 5111 5112 /* 5113 * nr_async_bios allows us to reliably return congestion to the 5114 * higher layers. Otherwise, the async bio makes it appear we have 5115 * made progress against dirty pages when we've really just put it 5116 * on a queue for later 5117 */ 5118 atomic_inc(&root->fs_info->nr_async_bios); 5119 WARN_ON(bio->bi_next); 5120 bio->bi_next = NULL; 5121 bio->bi_rw |= rw; 5122 5123 spin_lock(&device->io_lock); 5124 if (bio->bi_rw & REQ_SYNC) 5125 pending_bios = &device->pending_sync_bios; 5126 else 5127 pending_bios = &device->pending_bios; 5128 5129 if (pending_bios->tail) 5130 pending_bios->tail->bi_next = bio; 5131 5132 pending_bios->tail = bio; 5133 if (!pending_bios->head) 5134 pending_bios->head = bio; 5135 if (device->running_pending) 5136 should_queue = 0; 5137 5138 spin_unlock(&device->io_lock); 5139 5140 if (should_queue) 5141 btrfs_queue_worker(&root->fs_info->submit_workers, 5142 &device->work); 5143 } 5144 5145 static int bio_size_ok(struct block_device *bdev, struct bio *bio, 5146 sector_t sector) 5147 { 5148 struct bio_vec *prev; 5149 struct request_queue *q = bdev_get_queue(bdev); 5150 unsigned short max_sectors = queue_max_sectors(q); 5151 struct bvec_merge_data bvm = { 5152 .bi_bdev = bdev, 5153 .bi_sector = sector, 5154 .bi_rw = bio->bi_rw, 5155 }; 5156 5157 if (bio->bi_vcnt == 0) { 5158 WARN_ON(1); 5159 return 1; 5160 } 5161 5162 prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; 5163 if ((bio->bi_size >> 9) > max_sectors) 5164 return 0; 5165 5166 if (!q->merge_bvec_fn) 5167 return 1; 5168 5169 bvm.bi_size = bio->bi_size - prev->bv_len; 5170 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) 5171 return 0; 5172 return 1; 5173 } 5174 5175 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 5176 struct bio *bio, u64 physical, int dev_nr, 5177 int rw, int async) 5178 { 5179 struct btrfs_device *dev = bbio->stripes[dev_nr].dev; 5180 5181 bio->bi_private = bbio; 5182 bio->bi_private = merge_stripe_index_into_bio_private( 5183 bio->bi_private, (unsigned int)dev_nr); 5184 bio->bi_end_io = btrfs_end_bio; 5185 bio->bi_sector = physical >> 9; 5186 #ifdef DEBUG 5187 { 5188 struct rcu_string *name; 5189 5190 rcu_read_lock(); 5191 name = rcu_dereference(dev->name); 5192 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu " 5193 "(%s id %llu), size=%u\n", rw, 5194 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, 5195 name->str, dev->devid, bio->bi_size); 5196 rcu_read_unlock(); 5197 } 5198 #endif 5199 bio->bi_bdev = dev->bdev; 5200 if (async) 5201 btrfs_schedule_bio(root, dev, rw, bio); 5202 else 5203 btrfsic_submit_bio(rw, bio); 5204 } 5205 5206 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 5207 struct bio *first_bio, struct btrfs_device *dev, 5208 int dev_nr, int rw, int async) 5209 { 5210 struct bio_vec *bvec = first_bio->bi_io_vec; 5211 struct bio *bio; 5212 int nr_vecs = bio_get_nr_vecs(dev->bdev); 5213 u64 physical = bbio->stripes[dev_nr].physical; 5214 5215 again: 5216 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS); 5217 if (!bio) 5218 return -ENOMEM; 5219 5220 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) { 5221 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len, 5222 bvec->bv_offset) < bvec->bv_len) { 5223 u64 len = bio->bi_size; 5224 5225 atomic_inc(&bbio->stripes_pending); 5226 submit_stripe_bio(root, bbio, bio, physical, dev_nr, 5227 rw, async); 5228 physical += len; 5229 goto again; 5230 } 5231 bvec++; 5232 } 5233 5234 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async); 5235 return 0; 5236 } 5237 5238 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) 5239 { 5240 atomic_inc(&bbio->error); 5241 if (atomic_dec_and_test(&bbio->stripes_pending)) { 5242 bio->bi_private = bbio->private; 5243 bio->bi_end_io = bbio->end_io; 5244 bio->bi_bdev = (struct block_device *) 5245 (unsigned long)bbio->mirror_num; 5246 bio->bi_sector = logical >> 9; 5247 kfree(bbio); 5248 bio_endio(bio, -EIO); 5249 } 5250 } 5251 5252 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, 5253 int mirror_num, int async_submit) 5254 { 5255 struct btrfs_device *dev; 5256 struct bio *first_bio = bio; 5257 u64 logical = (u64)bio->bi_sector << 9; 5258 u64 length = 0; 5259 u64 map_length; 5260 u64 *raid_map = NULL; 5261 int ret; 5262 int dev_nr = 0; 5263 int total_devs = 1; 5264 struct btrfs_bio *bbio = NULL; 5265 5266 length = bio->bi_size; 5267 map_length = length; 5268 5269 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio, 5270 mirror_num, &raid_map); 5271 if (ret) /* -ENOMEM */ 5272 return ret; 5273 5274 total_devs = bbio->num_stripes; 5275 bbio->orig_bio = first_bio; 5276 bbio->private = first_bio->bi_private; 5277 bbio->end_io = first_bio->bi_end_io; 5278 atomic_set(&bbio->stripes_pending, bbio->num_stripes); 5279 5280 if (raid_map) { 5281 /* In this case, map_length has been set to the length of 5282 a single stripe; not the whole write */ 5283 if (rw & WRITE) { 5284 return raid56_parity_write(root, bio, bbio, 5285 raid_map, map_length); 5286 } else { 5287 return raid56_parity_recover(root, bio, bbio, 5288 raid_map, map_length, 5289 mirror_num); 5290 } 5291 } 5292 5293 if (map_length < length) { 5294 printk(KERN_CRIT "btrfs: mapping failed logical %llu bio len %llu " 5295 "len %llu\n", (unsigned long long)logical, 5296 (unsigned long long)length, 5297 (unsigned long long)map_length); 5298 BUG(); 5299 } 5300 5301 while (dev_nr < total_devs) { 5302 dev = bbio->stripes[dev_nr].dev; 5303 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) { 5304 bbio_error(bbio, first_bio, logical); 5305 dev_nr++; 5306 continue; 5307 } 5308 5309 /* 5310 * Check and see if we're ok with this bio based on it's size 5311 * and offset with the given device. 5312 */ 5313 if (!bio_size_ok(dev->bdev, first_bio, 5314 bbio->stripes[dev_nr].physical >> 9)) { 5315 ret = breakup_stripe_bio(root, bbio, first_bio, dev, 5316 dev_nr, rw, async_submit); 5317 BUG_ON(ret); 5318 dev_nr++; 5319 continue; 5320 } 5321 5322 if (dev_nr < total_devs - 1) { 5323 bio = bio_clone(first_bio, GFP_NOFS); 5324 BUG_ON(!bio); /* -ENOMEM */ 5325 } else { 5326 bio = first_bio; 5327 } 5328 5329 submit_stripe_bio(root, bbio, bio, 5330 bbio->stripes[dev_nr].physical, dev_nr, rw, 5331 async_submit); 5332 dev_nr++; 5333 } 5334 return 0; 5335 } 5336 5337 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, 5338 u8 *uuid, u8 *fsid) 5339 { 5340 struct btrfs_device *device; 5341 struct btrfs_fs_devices *cur_devices; 5342 5343 cur_devices = fs_info->fs_devices; 5344 while (cur_devices) { 5345 if (!fsid || 5346 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5347 device = __find_device(&cur_devices->devices, 5348 devid, uuid); 5349 if (device) 5350 return device; 5351 } 5352 cur_devices = cur_devices->seed; 5353 } 5354 return NULL; 5355 } 5356 5357 static struct btrfs_device *add_missing_dev(struct btrfs_root *root, 5358 u64 devid, u8 *dev_uuid) 5359 { 5360 struct btrfs_device *device; 5361 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5362 5363 device = kzalloc(sizeof(*device), GFP_NOFS); 5364 if (!device) 5365 return NULL; 5366 list_add(&device->dev_list, 5367 &fs_devices->devices); 5368 device->dev_root = root->fs_info->dev_root; 5369 device->devid = devid; 5370 device->work.func = pending_bios_fn; 5371 device->fs_devices = fs_devices; 5372 device->missing = 1; 5373 fs_devices->num_devices++; 5374 fs_devices->missing_devices++; 5375 spin_lock_init(&device->io_lock); 5376 INIT_LIST_HEAD(&device->dev_alloc_list); 5377 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE); 5378 return device; 5379 } 5380 5381 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, 5382 struct extent_buffer *leaf, 5383 struct btrfs_chunk *chunk) 5384 { 5385 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 5386 struct map_lookup *map; 5387 struct extent_map *em; 5388 u64 logical; 5389 u64 length; 5390 u64 devid; 5391 u8 uuid[BTRFS_UUID_SIZE]; 5392 int num_stripes; 5393 int ret; 5394 int i; 5395 5396 logical = key->offset; 5397 length = btrfs_chunk_length(leaf, chunk); 5398 5399 read_lock(&map_tree->map_tree.lock); 5400 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1); 5401 read_unlock(&map_tree->map_tree.lock); 5402 5403 /* already mapped? */ 5404 if (em && em->start <= logical && em->start + em->len > logical) { 5405 free_extent_map(em); 5406 return 0; 5407 } else if (em) { 5408 free_extent_map(em); 5409 } 5410 5411 em = alloc_extent_map(); 5412 if (!em) 5413 return -ENOMEM; 5414 num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 5415 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 5416 if (!map) { 5417 free_extent_map(em); 5418 return -ENOMEM; 5419 } 5420 5421 em->bdev = (struct block_device *)map; 5422 em->start = logical; 5423 em->len = length; 5424 em->orig_start = 0; 5425 em->block_start = 0; 5426 em->block_len = em->len; 5427 5428 map->num_stripes = num_stripes; 5429 map->io_width = btrfs_chunk_io_width(leaf, chunk); 5430 map->io_align = btrfs_chunk_io_align(leaf, chunk); 5431 map->sector_size = btrfs_chunk_sector_size(leaf, chunk); 5432 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); 5433 map->type = btrfs_chunk_type(leaf, chunk); 5434 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); 5435 for (i = 0; i < num_stripes; i++) { 5436 map->stripes[i].physical = 5437 btrfs_stripe_offset_nr(leaf, chunk, i); 5438 devid = btrfs_stripe_devid_nr(leaf, chunk, i); 5439 read_extent_buffer(leaf, uuid, (unsigned long) 5440 btrfs_stripe_dev_uuid_nr(chunk, i), 5441 BTRFS_UUID_SIZE); 5442 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid, 5443 uuid, NULL); 5444 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) { 5445 kfree(map); 5446 free_extent_map(em); 5447 return -EIO; 5448 } 5449 if (!map->stripes[i].dev) { 5450 map->stripes[i].dev = 5451 add_missing_dev(root, devid, uuid); 5452 if (!map->stripes[i].dev) { 5453 kfree(map); 5454 free_extent_map(em); 5455 return -EIO; 5456 } 5457 } 5458 map->stripes[i].dev->in_fs_metadata = 1; 5459 } 5460 5461 write_lock(&map_tree->map_tree.lock); 5462 ret = add_extent_mapping(&map_tree->map_tree, em); 5463 write_unlock(&map_tree->map_tree.lock); 5464 BUG_ON(ret); /* Tree corruption */ 5465 free_extent_map(em); 5466 5467 return 0; 5468 } 5469 5470 static void fill_device_from_item(struct extent_buffer *leaf, 5471 struct btrfs_dev_item *dev_item, 5472 struct btrfs_device *device) 5473 { 5474 unsigned long ptr; 5475 5476 device->devid = btrfs_device_id(leaf, dev_item); 5477 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); 5478 device->total_bytes = device->disk_total_bytes; 5479 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); 5480 device->type = btrfs_device_type(leaf, dev_item); 5481 device->io_align = btrfs_device_io_align(leaf, dev_item); 5482 device->io_width = btrfs_device_io_width(leaf, dev_item); 5483 device->sector_size = btrfs_device_sector_size(leaf, dev_item); 5484 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); 5485 device->is_tgtdev_for_dev_replace = 0; 5486 5487 ptr = (unsigned long)btrfs_device_uuid(dev_item); 5488 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 5489 } 5490 5491 static int open_seed_devices(struct btrfs_root *root, u8 *fsid) 5492 { 5493 struct btrfs_fs_devices *fs_devices; 5494 int ret; 5495 5496 BUG_ON(!mutex_is_locked(&uuid_mutex)); 5497 5498 fs_devices = root->fs_info->fs_devices->seed; 5499 while (fs_devices) { 5500 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5501 ret = 0; 5502 goto out; 5503 } 5504 fs_devices = fs_devices->seed; 5505 } 5506 5507 fs_devices = find_fsid(fsid); 5508 if (!fs_devices) { 5509 ret = -ENOENT; 5510 goto out; 5511 } 5512 5513 fs_devices = clone_fs_devices(fs_devices); 5514 if (IS_ERR(fs_devices)) { 5515 ret = PTR_ERR(fs_devices); 5516 goto out; 5517 } 5518 5519 ret = __btrfs_open_devices(fs_devices, FMODE_READ, 5520 root->fs_info->bdev_holder); 5521 if (ret) { 5522 free_fs_devices(fs_devices); 5523 goto out; 5524 } 5525 5526 if (!fs_devices->seeding) { 5527 __btrfs_close_devices(fs_devices); 5528 free_fs_devices(fs_devices); 5529 ret = -EINVAL; 5530 goto out; 5531 } 5532 5533 fs_devices->seed = root->fs_info->fs_devices->seed; 5534 root->fs_info->fs_devices->seed = fs_devices; 5535 out: 5536 return ret; 5537 } 5538 5539 static int read_one_dev(struct btrfs_root *root, 5540 struct extent_buffer *leaf, 5541 struct btrfs_dev_item *dev_item) 5542 { 5543 struct btrfs_device *device; 5544 u64 devid; 5545 int ret; 5546 u8 fs_uuid[BTRFS_UUID_SIZE]; 5547 u8 dev_uuid[BTRFS_UUID_SIZE]; 5548 5549 devid = btrfs_device_id(leaf, dev_item); 5550 read_extent_buffer(leaf, dev_uuid, 5551 (unsigned long)btrfs_device_uuid(dev_item), 5552 BTRFS_UUID_SIZE); 5553 read_extent_buffer(leaf, fs_uuid, 5554 (unsigned long)btrfs_device_fsid(dev_item), 5555 BTRFS_UUID_SIZE); 5556 5557 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) { 5558 ret = open_seed_devices(root, fs_uuid); 5559 if (ret && !btrfs_test_opt(root, DEGRADED)) 5560 return ret; 5561 } 5562 5563 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid); 5564 if (!device || !device->bdev) { 5565 if (!btrfs_test_opt(root, DEGRADED)) 5566 return -EIO; 5567 5568 if (!device) { 5569 printk(KERN_WARNING "warning devid %llu missing\n", 5570 (unsigned long long)devid); 5571 device = add_missing_dev(root, devid, dev_uuid); 5572 if (!device) 5573 return -ENOMEM; 5574 } else if (!device->missing) { 5575 /* 5576 * this happens when a device that was properly setup 5577 * in the device info lists suddenly goes bad. 5578 * device->bdev is NULL, and so we have to set 5579 * device->missing to one here 5580 */ 5581 root->fs_info->fs_devices->missing_devices++; 5582 device->missing = 1; 5583 } 5584 } 5585 5586 if (device->fs_devices != root->fs_info->fs_devices) { 5587 BUG_ON(device->writeable); 5588 if (device->generation != 5589 btrfs_device_generation(leaf, dev_item)) 5590 return -EINVAL; 5591 } 5592 5593 fill_device_from_item(leaf, dev_item, device); 5594 device->dev_root = root->fs_info->dev_root; 5595 device->in_fs_metadata = 1; 5596 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 5597 device->fs_devices->total_rw_bytes += device->total_bytes; 5598 spin_lock(&root->fs_info->free_chunk_lock); 5599 root->fs_info->free_chunk_space += device->total_bytes - 5600 device->bytes_used; 5601 spin_unlock(&root->fs_info->free_chunk_lock); 5602 } 5603 ret = 0; 5604 return ret; 5605 } 5606 5607 int btrfs_read_sys_array(struct btrfs_root *root) 5608 { 5609 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 5610 struct extent_buffer *sb; 5611 struct btrfs_disk_key *disk_key; 5612 struct btrfs_chunk *chunk; 5613 u8 *ptr; 5614 unsigned long sb_ptr; 5615 int ret = 0; 5616 u32 num_stripes; 5617 u32 array_size; 5618 u32 len = 0; 5619 u32 cur; 5620 struct btrfs_key key; 5621 5622 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET, 5623 BTRFS_SUPER_INFO_SIZE); 5624 if (!sb) 5625 return -ENOMEM; 5626 btrfs_set_buffer_uptodate(sb); 5627 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); 5628 /* 5629 * The sb extent buffer is artifical and just used to read the system array. 5630 * btrfs_set_buffer_uptodate() call does not properly mark all it's 5631 * pages up-to-date when the page is larger: extent does not cover the 5632 * whole page and consequently check_page_uptodate does not find all 5633 * the page's extents up-to-date (the hole beyond sb), 5634 * write_extent_buffer then triggers a WARN_ON. 5635 * 5636 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle, 5637 * but sb spans only this function. Add an explicit SetPageUptodate call 5638 * to silence the warning eg. on PowerPC 64. 5639 */ 5640 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE) 5641 SetPageUptodate(sb->pages[0]); 5642 5643 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); 5644 array_size = btrfs_super_sys_array_size(super_copy); 5645 5646 ptr = super_copy->sys_chunk_array; 5647 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array); 5648 cur = 0; 5649 5650 while (cur < array_size) { 5651 disk_key = (struct btrfs_disk_key *)ptr; 5652 btrfs_disk_key_to_cpu(&key, disk_key); 5653 5654 len = sizeof(*disk_key); ptr += len; 5655 sb_ptr += len; 5656 cur += len; 5657 5658 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 5659 chunk = (struct btrfs_chunk *)sb_ptr; 5660 ret = read_one_chunk(root, &key, sb, chunk); 5661 if (ret) 5662 break; 5663 num_stripes = btrfs_chunk_num_stripes(sb, chunk); 5664 len = btrfs_chunk_item_size(num_stripes); 5665 } else { 5666 ret = -EIO; 5667 break; 5668 } 5669 ptr += len; 5670 sb_ptr += len; 5671 cur += len; 5672 } 5673 free_extent_buffer(sb); 5674 return ret; 5675 } 5676 5677 int btrfs_read_chunk_tree(struct btrfs_root *root) 5678 { 5679 struct btrfs_path *path; 5680 struct extent_buffer *leaf; 5681 struct btrfs_key key; 5682 struct btrfs_key found_key; 5683 int ret; 5684 int slot; 5685 5686 root = root->fs_info->chunk_root; 5687 5688 path = btrfs_alloc_path(); 5689 if (!path) 5690 return -ENOMEM; 5691 5692 mutex_lock(&uuid_mutex); 5693 lock_chunks(root); 5694 5695 /* first we search for all of the device items, and then we 5696 * read in all of the chunk items. This way we can create chunk 5697 * mappings that reference all of the devices that are afound 5698 */ 5699 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 5700 key.offset = 0; 5701 key.type = 0; 5702 again: 5703 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5704 if (ret < 0) 5705 goto error; 5706 while (1) { 5707 leaf = path->nodes[0]; 5708 slot = path->slots[0]; 5709 if (slot >= btrfs_header_nritems(leaf)) { 5710 ret = btrfs_next_leaf(root, path); 5711 if (ret == 0) 5712 continue; 5713 if (ret < 0) 5714 goto error; 5715 break; 5716 } 5717 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5718 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5719 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID) 5720 break; 5721 if (found_key.type == BTRFS_DEV_ITEM_KEY) { 5722 struct btrfs_dev_item *dev_item; 5723 dev_item = btrfs_item_ptr(leaf, slot, 5724 struct btrfs_dev_item); 5725 ret = read_one_dev(root, leaf, dev_item); 5726 if (ret) 5727 goto error; 5728 } 5729 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { 5730 struct btrfs_chunk *chunk; 5731 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 5732 ret = read_one_chunk(root, &found_key, leaf, chunk); 5733 if (ret) 5734 goto error; 5735 } 5736 path->slots[0]++; 5737 } 5738 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5739 key.objectid = 0; 5740 btrfs_release_path(path); 5741 goto again; 5742 } 5743 ret = 0; 5744 error: 5745 unlock_chunks(root); 5746 mutex_unlock(&uuid_mutex); 5747 5748 btrfs_free_path(path); 5749 return ret; 5750 } 5751 5752 static void __btrfs_reset_dev_stats(struct btrfs_device *dev) 5753 { 5754 int i; 5755 5756 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5757 btrfs_dev_stat_reset(dev, i); 5758 } 5759 5760 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) 5761 { 5762 struct btrfs_key key; 5763 struct btrfs_key found_key; 5764 struct btrfs_root *dev_root = fs_info->dev_root; 5765 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5766 struct extent_buffer *eb; 5767 int slot; 5768 int ret = 0; 5769 struct btrfs_device *device; 5770 struct btrfs_path *path = NULL; 5771 int i; 5772 5773 path = btrfs_alloc_path(); 5774 if (!path) { 5775 ret = -ENOMEM; 5776 goto out; 5777 } 5778 5779 mutex_lock(&fs_devices->device_list_mutex); 5780 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5781 int item_size; 5782 struct btrfs_dev_stats_item *ptr; 5783 5784 key.objectid = 0; 5785 key.type = BTRFS_DEV_STATS_KEY; 5786 key.offset = device->devid; 5787 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 5788 if (ret) { 5789 __btrfs_reset_dev_stats(device); 5790 device->dev_stats_valid = 1; 5791 btrfs_release_path(path); 5792 continue; 5793 } 5794 slot = path->slots[0]; 5795 eb = path->nodes[0]; 5796 btrfs_item_key_to_cpu(eb, &found_key, slot); 5797 item_size = btrfs_item_size_nr(eb, slot); 5798 5799 ptr = btrfs_item_ptr(eb, slot, 5800 struct btrfs_dev_stats_item); 5801 5802 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5803 if (item_size >= (1 + i) * sizeof(__le64)) 5804 btrfs_dev_stat_set(device, i, 5805 btrfs_dev_stats_value(eb, ptr, i)); 5806 else 5807 btrfs_dev_stat_reset(device, i); 5808 } 5809 5810 device->dev_stats_valid = 1; 5811 btrfs_dev_stat_print_on_load(device); 5812 btrfs_release_path(path); 5813 } 5814 mutex_unlock(&fs_devices->device_list_mutex); 5815 5816 out: 5817 btrfs_free_path(path); 5818 return ret < 0 ? ret : 0; 5819 } 5820 5821 static int update_dev_stat_item(struct btrfs_trans_handle *trans, 5822 struct btrfs_root *dev_root, 5823 struct btrfs_device *device) 5824 { 5825 struct btrfs_path *path; 5826 struct btrfs_key key; 5827 struct extent_buffer *eb; 5828 struct btrfs_dev_stats_item *ptr; 5829 int ret; 5830 int i; 5831 5832 key.objectid = 0; 5833 key.type = BTRFS_DEV_STATS_KEY; 5834 key.offset = device->devid; 5835 5836 path = btrfs_alloc_path(); 5837 BUG_ON(!path); 5838 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 5839 if (ret < 0) { 5840 printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n", 5841 ret, rcu_str_deref(device->name)); 5842 goto out; 5843 } 5844 5845 if (ret == 0 && 5846 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 5847 /* need to delete old one and insert a new one */ 5848 ret = btrfs_del_item(trans, dev_root, path); 5849 if (ret != 0) { 5850 printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n", 5851 rcu_str_deref(device->name), ret); 5852 goto out; 5853 } 5854 ret = 1; 5855 } 5856 5857 if (ret == 1) { 5858 /* need to insert a new item */ 5859 btrfs_release_path(path); 5860 ret = btrfs_insert_empty_item(trans, dev_root, path, 5861 &key, sizeof(*ptr)); 5862 if (ret < 0) { 5863 printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n", 5864 rcu_str_deref(device->name), ret); 5865 goto out; 5866 } 5867 } 5868 5869 eb = path->nodes[0]; 5870 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); 5871 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5872 btrfs_set_dev_stats_value(eb, ptr, i, 5873 btrfs_dev_stat_read(device, i)); 5874 btrfs_mark_buffer_dirty(eb); 5875 5876 out: 5877 btrfs_free_path(path); 5878 return ret; 5879 } 5880 5881 /* 5882 * called from commit_transaction. Writes all changed device stats to disk. 5883 */ 5884 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, 5885 struct btrfs_fs_info *fs_info) 5886 { 5887 struct btrfs_root *dev_root = fs_info->dev_root; 5888 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5889 struct btrfs_device *device; 5890 int ret = 0; 5891 5892 mutex_lock(&fs_devices->device_list_mutex); 5893 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5894 if (!device->dev_stats_valid || !device->dev_stats_dirty) 5895 continue; 5896 5897 ret = update_dev_stat_item(trans, dev_root, device); 5898 if (!ret) 5899 device->dev_stats_dirty = 0; 5900 } 5901 mutex_unlock(&fs_devices->device_list_mutex); 5902 5903 return ret; 5904 } 5905 5906 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) 5907 { 5908 btrfs_dev_stat_inc(dev, index); 5909 btrfs_dev_stat_print_on_error(dev); 5910 } 5911 5912 void btrfs_dev_stat_print_on_error(struct btrfs_device *dev) 5913 { 5914 if (!dev->dev_stats_valid) 5915 return; 5916 printk_ratelimited_in_rcu(KERN_ERR 5917 "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5918 rcu_str_deref(dev->name), 5919 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5920 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5921 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5922 btrfs_dev_stat_read(dev, 5923 BTRFS_DEV_STAT_CORRUPTION_ERRS), 5924 btrfs_dev_stat_read(dev, 5925 BTRFS_DEV_STAT_GENERATION_ERRS)); 5926 } 5927 5928 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) 5929 { 5930 int i; 5931 5932 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5933 if (btrfs_dev_stat_read(dev, i) != 0) 5934 break; 5935 if (i == BTRFS_DEV_STAT_VALUES_MAX) 5936 return; /* all values == 0, suppress message */ 5937 5938 printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5939 rcu_str_deref(dev->name), 5940 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5941 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5942 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5943 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), 5944 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); 5945 } 5946 5947 int btrfs_get_dev_stats(struct btrfs_root *root, 5948 struct btrfs_ioctl_get_dev_stats *stats) 5949 { 5950 struct btrfs_device *dev; 5951 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5952 int i; 5953 5954 mutex_lock(&fs_devices->device_list_mutex); 5955 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL); 5956 mutex_unlock(&fs_devices->device_list_mutex); 5957 5958 if (!dev) { 5959 printk(KERN_WARNING 5960 "btrfs: get dev_stats failed, device not found\n"); 5961 return -ENODEV; 5962 } else if (!dev->dev_stats_valid) { 5963 printk(KERN_WARNING 5964 "btrfs: get dev_stats failed, not yet valid\n"); 5965 return -ENODEV; 5966 } else if (stats->flags & BTRFS_DEV_STATS_RESET) { 5967 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5968 if (stats->nr_items > i) 5969 stats->values[i] = 5970 btrfs_dev_stat_read_and_reset(dev, i); 5971 else 5972 btrfs_dev_stat_reset(dev, i); 5973 } 5974 } else { 5975 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5976 if (stats->nr_items > i) 5977 stats->values[i] = btrfs_dev_stat_read(dev, i); 5978 } 5979 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) 5980 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; 5981 return 0; 5982 } 5983 5984 int btrfs_scratch_superblock(struct btrfs_device *device) 5985 { 5986 struct buffer_head *bh; 5987 struct btrfs_super_block *disk_super; 5988 5989 bh = btrfs_read_dev_super(device->bdev); 5990 if (!bh) 5991 return -EINVAL; 5992 disk_super = (struct btrfs_super_block *)bh->b_data; 5993 5994 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 5995 set_buffer_dirty(bh); 5996 sync_dirty_buffer(bh); 5997 brelse(bh); 5998 5999 return 0; 6000 } 6001