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_error(struct btrfs_device *dev); 50 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); 51 52 static DEFINE_MUTEX(uuid_mutex); 53 static LIST_HEAD(fs_uuids); 54 55 static void lock_chunks(struct btrfs_root *root) 56 { 57 mutex_lock(&root->fs_info->chunk_mutex); 58 } 59 60 static void unlock_chunks(struct btrfs_root *root) 61 { 62 mutex_unlock(&root->fs_info->chunk_mutex); 63 } 64 65 static void free_fs_devices(struct btrfs_fs_devices *fs_devices) 66 { 67 struct btrfs_device *device; 68 WARN_ON(fs_devices->opened); 69 while (!list_empty(&fs_devices->devices)) { 70 device = list_entry(fs_devices->devices.next, 71 struct btrfs_device, dev_list); 72 list_del(&device->dev_list); 73 rcu_string_free(device->name); 74 kfree(device); 75 } 76 kfree(fs_devices); 77 } 78 79 static void btrfs_kobject_uevent(struct block_device *bdev, 80 enum kobject_action action) 81 { 82 int ret; 83 84 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 85 if (ret) 86 pr_warn("Sending event '%d' to kobject: '%s' (%p): failed\n", 87 action, 88 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 89 &disk_to_dev(bdev->bd_disk)->kobj); 90 } 91 92 void btrfs_cleanup_fs_uuids(void) 93 { 94 struct btrfs_fs_devices *fs_devices; 95 96 while (!list_empty(&fs_uuids)) { 97 fs_devices = list_entry(fs_uuids.next, 98 struct btrfs_fs_devices, list); 99 list_del(&fs_devices->list); 100 free_fs_devices(fs_devices); 101 } 102 } 103 104 static noinline struct btrfs_device *__find_device(struct list_head *head, 105 u64 devid, u8 *uuid) 106 { 107 struct btrfs_device *dev; 108 109 list_for_each_entry(dev, head, dev_list) { 110 if (dev->devid == devid && 111 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { 112 return dev; 113 } 114 } 115 return NULL; 116 } 117 118 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid) 119 { 120 struct btrfs_fs_devices *fs_devices; 121 122 list_for_each_entry(fs_devices, &fs_uuids, list) { 123 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) 124 return fs_devices; 125 } 126 return NULL; 127 } 128 129 static int 130 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder, 131 int flush, struct block_device **bdev, 132 struct buffer_head **bh) 133 { 134 int ret; 135 136 *bdev = blkdev_get_by_path(device_path, flags, holder); 137 138 if (IS_ERR(*bdev)) { 139 ret = PTR_ERR(*bdev); 140 printk(KERN_INFO "btrfs: open %s failed\n", device_path); 141 goto error; 142 } 143 144 if (flush) 145 filemap_write_and_wait((*bdev)->bd_inode->i_mapping); 146 ret = set_blocksize(*bdev, 4096); 147 if (ret) { 148 blkdev_put(*bdev, flags); 149 goto error; 150 } 151 invalidate_bdev(*bdev); 152 *bh = btrfs_read_dev_super(*bdev); 153 if (!*bh) { 154 ret = -EINVAL; 155 blkdev_put(*bdev, flags); 156 goto error; 157 } 158 159 return 0; 160 161 error: 162 *bdev = NULL; 163 *bh = NULL; 164 return ret; 165 } 166 167 static void requeue_list(struct btrfs_pending_bios *pending_bios, 168 struct bio *head, struct bio *tail) 169 { 170 171 struct bio *old_head; 172 173 old_head = pending_bios->head; 174 pending_bios->head = head; 175 if (pending_bios->tail) 176 tail->bi_next = old_head; 177 else 178 pending_bios->tail = tail; 179 } 180 181 /* 182 * we try to collect pending bios for a device so we don't get a large 183 * number of procs sending bios down to the same device. This greatly 184 * improves the schedulers ability to collect and merge the bios. 185 * 186 * But, it also turns into a long list of bios to process and that is sure 187 * to eventually make the worker thread block. The solution here is to 188 * make some progress and then put this work struct back at the end of 189 * the list if the block device is congested. This way, multiple devices 190 * can make progress from a single worker thread. 191 */ 192 static noinline void run_scheduled_bios(struct btrfs_device *device) 193 { 194 struct bio *pending; 195 struct backing_dev_info *bdi; 196 struct btrfs_fs_info *fs_info; 197 struct btrfs_pending_bios *pending_bios; 198 struct bio *tail; 199 struct bio *cur; 200 int again = 0; 201 unsigned long num_run; 202 unsigned long batch_run = 0; 203 unsigned long limit; 204 unsigned long last_waited = 0; 205 int force_reg = 0; 206 int sync_pending = 0; 207 struct blk_plug plug; 208 209 /* 210 * this function runs all the bios we've collected for 211 * a particular device. We don't want to wander off to 212 * another device without first sending all of these down. 213 * So, setup a plug here and finish it off before we return 214 */ 215 blk_start_plug(&plug); 216 217 bdi = blk_get_backing_dev_info(device->bdev); 218 fs_info = device->dev_root->fs_info; 219 limit = btrfs_async_submit_limit(fs_info); 220 limit = limit * 2 / 3; 221 222 loop: 223 spin_lock(&device->io_lock); 224 225 loop_lock: 226 num_run = 0; 227 228 /* take all the bios off the list at once and process them 229 * later on (without the lock held). But, remember the 230 * tail and other pointers so the bios can be properly reinserted 231 * into the list if we hit congestion 232 */ 233 if (!force_reg && device->pending_sync_bios.head) { 234 pending_bios = &device->pending_sync_bios; 235 force_reg = 1; 236 } else { 237 pending_bios = &device->pending_bios; 238 force_reg = 0; 239 } 240 241 pending = pending_bios->head; 242 tail = pending_bios->tail; 243 WARN_ON(pending && !tail); 244 245 /* 246 * if pending was null this time around, no bios need processing 247 * at all and we can stop. Otherwise it'll loop back up again 248 * and do an additional check so no bios are missed. 249 * 250 * device->running_pending is used to synchronize with the 251 * schedule_bio code. 252 */ 253 if (device->pending_sync_bios.head == NULL && 254 device->pending_bios.head == NULL) { 255 again = 0; 256 device->running_pending = 0; 257 } else { 258 again = 1; 259 device->running_pending = 1; 260 } 261 262 pending_bios->head = NULL; 263 pending_bios->tail = NULL; 264 265 spin_unlock(&device->io_lock); 266 267 while (pending) { 268 269 rmb(); 270 /* we want to work on both lists, but do more bios on the 271 * sync list than the regular list 272 */ 273 if ((num_run > 32 && 274 pending_bios != &device->pending_sync_bios && 275 device->pending_sync_bios.head) || 276 (num_run > 64 && pending_bios == &device->pending_sync_bios && 277 device->pending_bios.head)) { 278 spin_lock(&device->io_lock); 279 requeue_list(pending_bios, pending, tail); 280 goto loop_lock; 281 } 282 283 cur = pending; 284 pending = pending->bi_next; 285 cur->bi_next = NULL; 286 287 if (atomic_dec_return(&fs_info->nr_async_bios) < limit && 288 waitqueue_active(&fs_info->async_submit_wait)) 289 wake_up(&fs_info->async_submit_wait); 290 291 BUG_ON(atomic_read(&cur->bi_cnt) == 0); 292 293 /* 294 * if we're doing the sync list, record that our 295 * plug has some sync requests on it 296 * 297 * If we're doing the regular list and there are 298 * sync requests sitting around, unplug before 299 * we add more 300 */ 301 if (pending_bios == &device->pending_sync_bios) { 302 sync_pending = 1; 303 } else if (sync_pending) { 304 blk_finish_plug(&plug); 305 blk_start_plug(&plug); 306 sync_pending = 0; 307 } 308 309 btrfsic_submit_bio(cur->bi_rw, cur); 310 num_run++; 311 batch_run++; 312 if (need_resched()) 313 cond_resched(); 314 315 /* 316 * we made progress, there is more work to do and the bdi 317 * is now congested. Back off and let other work structs 318 * run instead 319 */ 320 if (pending && bdi_write_congested(bdi) && batch_run > 8 && 321 fs_info->fs_devices->open_devices > 1) { 322 struct io_context *ioc; 323 324 ioc = current->io_context; 325 326 /* 327 * the main goal here is that we don't want to 328 * block if we're going to be able to submit 329 * more requests without blocking. 330 * 331 * This code does two great things, it pokes into 332 * the elevator code from a filesystem _and_ 333 * it makes assumptions about how batching works. 334 */ 335 if (ioc && ioc->nr_batch_requests > 0 && 336 time_before(jiffies, ioc->last_waited + HZ/50UL) && 337 (last_waited == 0 || 338 ioc->last_waited == last_waited)) { 339 /* 340 * we want to go through our batch of 341 * requests and stop. So, we copy out 342 * the ioc->last_waited time and test 343 * against it before looping 344 */ 345 last_waited = ioc->last_waited; 346 if (need_resched()) 347 cond_resched(); 348 continue; 349 } 350 spin_lock(&device->io_lock); 351 requeue_list(pending_bios, pending, tail); 352 device->running_pending = 1; 353 354 spin_unlock(&device->io_lock); 355 btrfs_requeue_work(&device->work); 356 goto done; 357 } 358 /* unplug every 64 requests just for good measure */ 359 if (batch_run % 64 == 0) { 360 blk_finish_plug(&plug); 361 blk_start_plug(&plug); 362 sync_pending = 0; 363 } 364 } 365 366 cond_resched(); 367 if (again) 368 goto loop; 369 370 spin_lock(&device->io_lock); 371 if (device->pending_bios.head || device->pending_sync_bios.head) 372 goto loop_lock; 373 spin_unlock(&device->io_lock); 374 375 done: 376 blk_finish_plug(&plug); 377 } 378 379 static void pending_bios_fn(struct btrfs_work *work) 380 { 381 struct btrfs_device *device; 382 383 device = container_of(work, struct btrfs_device, work); 384 run_scheduled_bios(device); 385 } 386 387 static noinline int device_list_add(const char *path, 388 struct btrfs_super_block *disk_super, 389 u64 devid, struct btrfs_fs_devices **fs_devices_ret) 390 { 391 struct btrfs_device *device; 392 struct btrfs_fs_devices *fs_devices; 393 struct rcu_string *name; 394 u64 found_transid = btrfs_super_generation(disk_super); 395 396 fs_devices = find_fsid(disk_super->fsid); 397 if (!fs_devices) { 398 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 399 if (!fs_devices) 400 return -ENOMEM; 401 INIT_LIST_HEAD(&fs_devices->devices); 402 INIT_LIST_HEAD(&fs_devices->alloc_list); 403 list_add(&fs_devices->list, &fs_uuids); 404 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE); 405 fs_devices->latest_devid = devid; 406 fs_devices->latest_trans = found_transid; 407 mutex_init(&fs_devices->device_list_mutex); 408 device = NULL; 409 } else { 410 device = __find_device(&fs_devices->devices, devid, 411 disk_super->dev_item.uuid); 412 } 413 if (!device) { 414 if (fs_devices->opened) 415 return -EBUSY; 416 417 device = kzalloc(sizeof(*device), GFP_NOFS); 418 if (!device) { 419 /* we can safely leave the fs_devices entry around */ 420 return -ENOMEM; 421 } 422 device->devid = devid; 423 device->dev_stats_valid = 0; 424 device->work.func = pending_bios_fn; 425 memcpy(device->uuid, disk_super->dev_item.uuid, 426 BTRFS_UUID_SIZE); 427 spin_lock_init(&device->io_lock); 428 429 name = rcu_string_strdup(path, GFP_NOFS); 430 if (!name) { 431 kfree(device); 432 return -ENOMEM; 433 } 434 rcu_assign_pointer(device->name, name); 435 INIT_LIST_HEAD(&device->dev_alloc_list); 436 437 /* init readahead state */ 438 spin_lock_init(&device->reada_lock); 439 device->reada_curr_zone = NULL; 440 atomic_set(&device->reada_in_flight, 0); 441 device->reada_next = 0; 442 INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT); 443 INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT); 444 445 mutex_lock(&fs_devices->device_list_mutex); 446 list_add_rcu(&device->dev_list, &fs_devices->devices); 447 mutex_unlock(&fs_devices->device_list_mutex); 448 449 device->fs_devices = fs_devices; 450 fs_devices->num_devices++; 451 } else if (!device->name || strcmp(device->name->str, path)) { 452 name = rcu_string_strdup(path, GFP_NOFS); 453 if (!name) 454 return -ENOMEM; 455 rcu_string_free(device->name); 456 rcu_assign_pointer(device->name, name); 457 if (device->missing) { 458 fs_devices->missing_devices--; 459 device->missing = 0; 460 } 461 } 462 463 if (found_transid > fs_devices->latest_trans) { 464 fs_devices->latest_devid = devid; 465 fs_devices->latest_trans = found_transid; 466 } 467 *fs_devices_ret = fs_devices; 468 return 0; 469 } 470 471 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) 472 { 473 struct btrfs_fs_devices *fs_devices; 474 struct btrfs_device *device; 475 struct btrfs_device *orig_dev; 476 477 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 478 if (!fs_devices) 479 return ERR_PTR(-ENOMEM); 480 481 INIT_LIST_HEAD(&fs_devices->devices); 482 INIT_LIST_HEAD(&fs_devices->alloc_list); 483 INIT_LIST_HEAD(&fs_devices->list); 484 mutex_init(&fs_devices->device_list_mutex); 485 fs_devices->latest_devid = orig->latest_devid; 486 fs_devices->latest_trans = orig->latest_trans; 487 fs_devices->total_devices = orig->total_devices; 488 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid)); 489 490 /* We have held the volume lock, it is safe to get the devices. */ 491 list_for_each_entry(orig_dev, &orig->devices, dev_list) { 492 struct rcu_string *name; 493 494 device = kzalloc(sizeof(*device), GFP_NOFS); 495 if (!device) 496 goto error; 497 498 /* 499 * This is ok to do without rcu read locked because we hold the 500 * uuid mutex so nothing we touch in here is going to disappear. 501 */ 502 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS); 503 if (!name) { 504 kfree(device); 505 goto error; 506 } 507 rcu_assign_pointer(device->name, name); 508 509 device->devid = orig_dev->devid; 510 device->work.func = pending_bios_fn; 511 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid)); 512 spin_lock_init(&device->io_lock); 513 INIT_LIST_HEAD(&device->dev_list); 514 INIT_LIST_HEAD(&device->dev_alloc_list); 515 516 list_add(&device->dev_list, &fs_devices->devices); 517 device->fs_devices = fs_devices; 518 fs_devices->num_devices++; 519 } 520 return fs_devices; 521 error: 522 free_fs_devices(fs_devices); 523 return ERR_PTR(-ENOMEM); 524 } 525 526 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info, 527 struct btrfs_fs_devices *fs_devices, int step) 528 { 529 struct btrfs_device *device, *next; 530 531 struct block_device *latest_bdev = NULL; 532 u64 latest_devid = 0; 533 u64 latest_transid = 0; 534 535 mutex_lock(&uuid_mutex); 536 again: 537 /* This is the initialized path, it is safe to release the devices. */ 538 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 539 if (device->in_fs_metadata) { 540 if (!device->is_tgtdev_for_dev_replace && 541 (!latest_transid || 542 device->generation > latest_transid)) { 543 latest_devid = device->devid; 544 latest_transid = device->generation; 545 latest_bdev = device->bdev; 546 } 547 continue; 548 } 549 550 if (device->devid == BTRFS_DEV_REPLACE_DEVID) { 551 /* 552 * In the first step, keep the device which has 553 * the correct fsid and the devid that is used 554 * for the dev_replace procedure. 555 * In the second step, the dev_replace state is 556 * read from the device tree and it is known 557 * whether the procedure is really active or 558 * not, which means whether this device is 559 * used or whether it should be removed. 560 */ 561 if (step == 0 || device->is_tgtdev_for_dev_replace) { 562 continue; 563 } 564 } 565 if (device->bdev) { 566 blkdev_put(device->bdev, device->mode); 567 device->bdev = NULL; 568 fs_devices->open_devices--; 569 } 570 if (device->writeable) { 571 list_del_init(&device->dev_alloc_list); 572 device->writeable = 0; 573 if (!device->is_tgtdev_for_dev_replace) 574 fs_devices->rw_devices--; 575 } 576 list_del_init(&device->dev_list); 577 fs_devices->num_devices--; 578 rcu_string_free(device->name); 579 kfree(device); 580 } 581 582 if (fs_devices->seed) { 583 fs_devices = fs_devices->seed; 584 goto again; 585 } 586 587 fs_devices->latest_bdev = latest_bdev; 588 fs_devices->latest_devid = latest_devid; 589 fs_devices->latest_trans = latest_transid; 590 591 mutex_unlock(&uuid_mutex); 592 } 593 594 static void __free_device(struct work_struct *work) 595 { 596 struct btrfs_device *device; 597 598 device = container_of(work, struct btrfs_device, rcu_work); 599 600 if (device->bdev) 601 blkdev_put(device->bdev, device->mode); 602 603 rcu_string_free(device->name); 604 kfree(device); 605 } 606 607 static void free_device(struct rcu_head *head) 608 { 609 struct btrfs_device *device; 610 611 device = container_of(head, struct btrfs_device, rcu); 612 613 INIT_WORK(&device->rcu_work, __free_device); 614 schedule_work(&device->rcu_work); 615 } 616 617 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 618 { 619 struct btrfs_device *device; 620 621 if (--fs_devices->opened > 0) 622 return 0; 623 624 mutex_lock(&fs_devices->device_list_mutex); 625 list_for_each_entry(device, &fs_devices->devices, dev_list) { 626 struct btrfs_device *new_device; 627 struct rcu_string *name; 628 629 if (device->bdev) 630 fs_devices->open_devices--; 631 632 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 633 list_del_init(&device->dev_alloc_list); 634 fs_devices->rw_devices--; 635 } 636 637 if (device->can_discard) 638 fs_devices->num_can_discard--; 639 640 new_device = kmalloc(sizeof(*new_device), GFP_NOFS); 641 BUG_ON(!new_device); /* -ENOMEM */ 642 memcpy(new_device, device, sizeof(*new_device)); 643 644 /* Safe because we are under uuid_mutex */ 645 if (device->name) { 646 name = rcu_string_strdup(device->name->str, GFP_NOFS); 647 BUG_ON(device->name && !name); /* -ENOMEM */ 648 rcu_assign_pointer(new_device->name, name); 649 } 650 new_device->bdev = NULL; 651 new_device->writeable = 0; 652 new_device->in_fs_metadata = 0; 653 new_device->can_discard = 0; 654 spin_lock_init(&new_device->io_lock); 655 list_replace_rcu(&device->dev_list, &new_device->dev_list); 656 657 call_rcu(&device->rcu, free_device); 658 } 659 mutex_unlock(&fs_devices->device_list_mutex); 660 661 WARN_ON(fs_devices->open_devices); 662 WARN_ON(fs_devices->rw_devices); 663 fs_devices->opened = 0; 664 fs_devices->seeding = 0; 665 666 return 0; 667 } 668 669 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 670 { 671 struct btrfs_fs_devices *seed_devices = NULL; 672 int ret; 673 674 mutex_lock(&uuid_mutex); 675 ret = __btrfs_close_devices(fs_devices); 676 if (!fs_devices->opened) { 677 seed_devices = fs_devices->seed; 678 fs_devices->seed = NULL; 679 } 680 mutex_unlock(&uuid_mutex); 681 682 while (seed_devices) { 683 fs_devices = seed_devices; 684 seed_devices = fs_devices->seed; 685 __btrfs_close_devices(fs_devices); 686 free_fs_devices(fs_devices); 687 } 688 /* 689 * Wait for rcu kworkers under __btrfs_close_devices 690 * to finish all blkdev_puts so device is really 691 * free when umount is done. 692 */ 693 rcu_barrier(); 694 return ret; 695 } 696 697 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 698 fmode_t flags, void *holder) 699 { 700 struct request_queue *q; 701 struct block_device *bdev; 702 struct list_head *head = &fs_devices->devices; 703 struct btrfs_device *device; 704 struct block_device *latest_bdev = NULL; 705 struct buffer_head *bh; 706 struct btrfs_super_block *disk_super; 707 u64 latest_devid = 0; 708 u64 latest_transid = 0; 709 u64 devid; 710 int seeding = 1; 711 int ret = 0; 712 713 flags |= FMODE_EXCL; 714 715 list_for_each_entry(device, head, dev_list) { 716 if (device->bdev) 717 continue; 718 if (!device->name) 719 continue; 720 721 /* Just open everything we can; ignore failures here */ 722 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, 723 &bdev, &bh)) 724 continue; 725 726 disk_super = (struct btrfs_super_block *)bh->b_data; 727 devid = btrfs_stack_device_id(&disk_super->dev_item); 728 if (devid != device->devid) 729 goto error_brelse; 730 731 if (memcmp(device->uuid, disk_super->dev_item.uuid, 732 BTRFS_UUID_SIZE)) 733 goto error_brelse; 734 735 device->generation = btrfs_super_generation(disk_super); 736 if (!latest_transid || device->generation > latest_transid) { 737 latest_devid = devid; 738 latest_transid = device->generation; 739 latest_bdev = bdev; 740 } 741 742 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { 743 device->writeable = 0; 744 } else { 745 device->writeable = !bdev_read_only(bdev); 746 seeding = 0; 747 } 748 749 q = bdev_get_queue(bdev); 750 if (blk_queue_discard(q)) { 751 device->can_discard = 1; 752 fs_devices->num_can_discard++; 753 } 754 755 device->bdev = bdev; 756 device->in_fs_metadata = 0; 757 device->mode = flags; 758 759 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 760 fs_devices->rotating = 1; 761 762 fs_devices->open_devices++; 763 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 764 fs_devices->rw_devices++; 765 list_add(&device->dev_alloc_list, 766 &fs_devices->alloc_list); 767 } 768 brelse(bh); 769 continue; 770 771 error_brelse: 772 brelse(bh); 773 blkdev_put(bdev, flags); 774 continue; 775 } 776 if (fs_devices->open_devices == 0) { 777 ret = -EINVAL; 778 goto out; 779 } 780 fs_devices->seeding = seeding; 781 fs_devices->opened = 1; 782 fs_devices->latest_bdev = latest_bdev; 783 fs_devices->latest_devid = latest_devid; 784 fs_devices->latest_trans = latest_transid; 785 fs_devices->total_rw_bytes = 0; 786 out: 787 return ret; 788 } 789 790 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 791 fmode_t flags, void *holder) 792 { 793 int ret; 794 795 mutex_lock(&uuid_mutex); 796 if (fs_devices->opened) { 797 fs_devices->opened++; 798 ret = 0; 799 } else { 800 ret = __btrfs_open_devices(fs_devices, flags, holder); 801 } 802 mutex_unlock(&uuid_mutex); 803 return ret; 804 } 805 806 /* 807 * Look for a btrfs signature on a device. This may be called out of the mount path 808 * and we are not allowed to call set_blocksize during the scan. The superblock 809 * is read via pagecache 810 */ 811 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, 812 struct btrfs_fs_devices **fs_devices_ret) 813 { 814 struct btrfs_super_block *disk_super; 815 struct block_device *bdev; 816 struct page *page; 817 void *p; 818 int ret = -EINVAL; 819 u64 devid; 820 u64 transid; 821 u64 total_devices; 822 u64 bytenr; 823 pgoff_t index; 824 825 /* 826 * we would like to check all the supers, but that would make 827 * a btrfs mount succeed after a mkfs from a different FS. 828 * So, we need to add a special mount option to scan for 829 * later supers, using BTRFS_SUPER_MIRROR_MAX instead 830 */ 831 bytenr = btrfs_sb_offset(0); 832 flags |= FMODE_EXCL; 833 mutex_lock(&uuid_mutex); 834 835 bdev = blkdev_get_by_path(path, flags, holder); 836 837 if (IS_ERR(bdev)) { 838 ret = PTR_ERR(bdev); 839 goto error; 840 } 841 842 /* make sure our super fits in the device */ 843 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode)) 844 goto error_bdev_put; 845 846 /* make sure our super fits in the page */ 847 if (sizeof(*disk_super) > PAGE_CACHE_SIZE) 848 goto error_bdev_put; 849 850 /* make sure our super doesn't straddle pages on disk */ 851 index = bytenr >> PAGE_CACHE_SHIFT; 852 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index) 853 goto error_bdev_put; 854 855 /* pull in the page with our super */ 856 page = read_cache_page_gfp(bdev->bd_inode->i_mapping, 857 index, GFP_NOFS); 858 859 if (IS_ERR_OR_NULL(page)) 860 goto error_bdev_put; 861 862 p = kmap(page); 863 864 /* align our pointer to the offset of the super block */ 865 disk_super = p + (bytenr & ~PAGE_CACHE_MASK); 866 867 if (btrfs_super_bytenr(disk_super) != bytenr || 868 disk_super->magic != cpu_to_le64(BTRFS_MAGIC)) 869 goto error_unmap; 870 871 devid = btrfs_stack_device_id(&disk_super->dev_item); 872 transid = btrfs_super_generation(disk_super); 873 total_devices = btrfs_super_num_devices(disk_super); 874 875 if (disk_super->label[0]) { 876 if (disk_super->label[BTRFS_LABEL_SIZE - 1]) 877 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0'; 878 printk(KERN_INFO "device label %s ", disk_super->label); 879 } else { 880 printk(KERN_INFO "device fsid %pU ", disk_super->fsid); 881 } 882 883 printk(KERN_CONT "devid %llu transid %llu %s\n", 884 (unsigned long long)devid, (unsigned long long)transid, path); 885 886 ret = device_list_add(path, disk_super, devid, fs_devices_ret); 887 if (!ret && fs_devices_ret) 888 (*fs_devices_ret)->total_devices = total_devices; 889 890 error_unmap: 891 kunmap(page); 892 page_cache_release(page); 893 894 error_bdev_put: 895 blkdev_put(bdev, flags); 896 error: 897 mutex_unlock(&uuid_mutex); 898 return ret; 899 } 900 901 /* helper to account the used device space in the range */ 902 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, 903 u64 end, u64 *length) 904 { 905 struct btrfs_key key; 906 struct btrfs_root *root = device->dev_root; 907 struct btrfs_dev_extent *dev_extent; 908 struct btrfs_path *path; 909 u64 extent_end; 910 int ret; 911 int slot; 912 struct extent_buffer *l; 913 914 *length = 0; 915 916 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace) 917 return 0; 918 919 path = btrfs_alloc_path(); 920 if (!path) 921 return -ENOMEM; 922 path->reada = 2; 923 924 key.objectid = device->devid; 925 key.offset = start; 926 key.type = BTRFS_DEV_EXTENT_KEY; 927 928 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 929 if (ret < 0) 930 goto out; 931 if (ret > 0) { 932 ret = btrfs_previous_item(root, path, key.objectid, key.type); 933 if (ret < 0) 934 goto out; 935 } 936 937 while (1) { 938 l = path->nodes[0]; 939 slot = path->slots[0]; 940 if (slot >= btrfs_header_nritems(l)) { 941 ret = btrfs_next_leaf(root, path); 942 if (ret == 0) 943 continue; 944 if (ret < 0) 945 goto out; 946 947 break; 948 } 949 btrfs_item_key_to_cpu(l, &key, slot); 950 951 if (key.objectid < device->devid) 952 goto next; 953 954 if (key.objectid > device->devid) 955 break; 956 957 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 958 goto next; 959 960 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 961 extent_end = key.offset + btrfs_dev_extent_length(l, 962 dev_extent); 963 if (key.offset <= start && extent_end > end) { 964 *length = end - start + 1; 965 break; 966 } else if (key.offset <= start && extent_end > start) 967 *length += extent_end - start; 968 else if (key.offset > start && extent_end <= end) 969 *length += extent_end - key.offset; 970 else if (key.offset > start && key.offset <= end) { 971 *length += end - key.offset + 1; 972 break; 973 } else if (key.offset > end) 974 break; 975 976 next: 977 path->slots[0]++; 978 } 979 ret = 0; 980 out: 981 btrfs_free_path(path); 982 return ret; 983 } 984 985 static int contains_pending_extent(struct btrfs_trans_handle *trans, 986 struct btrfs_device *device, 987 u64 *start, u64 len) 988 { 989 struct extent_map *em; 990 int ret = 0; 991 992 list_for_each_entry(em, &trans->transaction->pending_chunks, list) { 993 struct map_lookup *map; 994 int i; 995 996 map = (struct map_lookup *)em->bdev; 997 for (i = 0; i < map->num_stripes; i++) { 998 if (map->stripes[i].dev != device) 999 continue; 1000 if (map->stripes[i].physical >= *start + len || 1001 map->stripes[i].physical + em->orig_block_len <= 1002 *start) 1003 continue; 1004 *start = map->stripes[i].physical + 1005 em->orig_block_len; 1006 ret = 1; 1007 } 1008 } 1009 1010 return ret; 1011 } 1012 1013 1014 /* 1015 * find_free_dev_extent - find free space in the specified device 1016 * @device: the device which we search the free space in 1017 * @num_bytes: the size of the free space that we need 1018 * @start: store the start of the free space. 1019 * @len: the size of the free space. that we find, or the size of the max 1020 * free space if we don't find suitable free space 1021 * 1022 * this uses a pretty simple search, the expectation is that it is 1023 * called very infrequently and that a given device has a small number 1024 * of extents 1025 * 1026 * @start is used to store the start of the free space if we find. But if we 1027 * don't find suitable free space, it will be used to store the start position 1028 * of the max free space. 1029 * 1030 * @len is used to store the size of the free space that we find. 1031 * But if we don't find suitable free space, it is used to store the size of 1032 * the max free space. 1033 */ 1034 int find_free_dev_extent(struct btrfs_trans_handle *trans, 1035 struct btrfs_device *device, u64 num_bytes, 1036 u64 *start, u64 *len) 1037 { 1038 struct btrfs_key key; 1039 struct btrfs_root *root = device->dev_root; 1040 struct btrfs_dev_extent *dev_extent; 1041 struct btrfs_path *path; 1042 u64 hole_size; 1043 u64 max_hole_start; 1044 u64 max_hole_size; 1045 u64 extent_end; 1046 u64 search_start; 1047 u64 search_end = device->total_bytes; 1048 int ret; 1049 int slot; 1050 struct extent_buffer *l; 1051 1052 /* FIXME use last free of some kind */ 1053 1054 /* we don't want to overwrite the superblock on the drive, 1055 * so we make sure to start at an offset of at least 1MB 1056 */ 1057 search_start = max(root->fs_info->alloc_start, 1024ull * 1024); 1058 1059 path = btrfs_alloc_path(); 1060 if (!path) 1061 return -ENOMEM; 1062 again: 1063 max_hole_start = search_start; 1064 max_hole_size = 0; 1065 hole_size = 0; 1066 1067 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) { 1068 ret = -ENOSPC; 1069 goto out; 1070 } 1071 1072 path->reada = 2; 1073 path->search_commit_root = 1; 1074 path->skip_locking = 1; 1075 1076 key.objectid = device->devid; 1077 key.offset = search_start; 1078 key.type = BTRFS_DEV_EXTENT_KEY; 1079 1080 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1081 if (ret < 0) 1082 goto out; 1083 if (ret > 0) { 1084 ret = btrfs_previous_item(root, path, key.objectid, key.type); 1085 if (ret < 0) 1086 goto out; 1087 } 1088 1089 while (1) { 1090 l = path->nodes[0]; 1091 slot = path->slots[0]; 1092 if (slot >= btrfs_header_nritems(l)) { 1093 ret = btrfs_next_leaf(root, path); 1094 if (ret == 0) 1095 continue; 1096 if (ret < 0) 1097 goto out; 1098 1099 break; 1100 } 1101 btrfs_item_key_to_cpu(l, &key, slot); 1102 1103 if (key.objectid < device->devid) 1104 goto next; 1105 1106 if (key.objectid > device->devid) 1107 break; 1108 1109 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 1110 goto next; 1111 1112 if (key.offset > search_start) { 1113 hole_size = key.offset - search_start; 1114 1115 /* 1116 * Have to check before we set max_hole_start, otherwise 1117 * we could end up sending back this offset anyway. 1118 */ 1119 if (contains_pending_extent(trans, device, 1120 &search_start, 1121 hole_size)) 1122 hole_size = 0; 1123 1124 if (hole_size > max_hole_size) { 1125 max_hole_start = search_start; 1126 max_hole_size = hole_size; 1127 } 1128 1129 /* 1130 * If this free space is greater than which we need, 1131 * it must be the max free space that we have found 1132 * until now, so max_hole_start must point to the start 1133 * of this free space and the length of this free space 1134 * is stored in max_hole_size. Thus, we return 1135 * max_hole_start and max_hole_size and go back to the 1136 * caller. 1137 */ 1138 if (hole_size >= num_bytes) { 1139 ret = 0; 1140 goto out; 1141 } 1142 } 1143 1144 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 1145 extent_end = key.offset + btrfs_dev_extent_length(l, 1146 dev_extent); 1147 if (extent_end > search_start) 1148 search_start = extent_end; 1149 next: 1150 path->slots[0]++; 1151 cond_resched(); 1152 } 1153 1154 /* 1155 * At this point, search_start should be the end of 1156 * allocated dev extents, and when shrinking the device, 1157 * search_end may be smaller than search_start. 1158 */ 1159 if (search_end > search_start) 1160 hole_size = search_end - search_start; 1161 1162 if (hole_size > max_hole_size) { 1163 max_hole_start = search_start; 1164 max_hole_size = hole_size; 1165 } 1166 1167 if (contains_pending_extent(trans, device, &search_start, hole_size)) { 1168 btrfs_release_path(path); 1169 goto again; 1170 } 1171 1172 /* See above. */ 1173 if (hole_size < num_bytes) 1174 ret = -ENOSPC; 1175 else 1176 ret = 0; 1177 1178 out: 1179 btrfs_free_path(path); 1180 *start = max_hole_start; 1181 if (len) 1182 *len = max_hole_size; 1183 return ret; 1184 } 1185 1186 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, 1187 struct btrfs_device *device, 1188 u64 start) 1189 { 1190 int ret; 1191 struct btrfs_path *path; 1192 struct btrfs_root *root = device->dev_root; 1193 struct btrfs_key key; 1194 struct btrfs_key found_key; 1195 struct extent_buffer *leaf = NULL; 1196 struct btrfs_dev_extent *extent = NULL; 1197 1198 path = btrfs_alloc_path(); 1199 if (!path) 1200 return -ENOMEM; 1201 1202 key.objectid = device->devid; 1203 key.offset = start; 1204 key.type = BTRFS_DEV_EXTENT_KEY; 1205 again: 1206 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1207 if (ret > 0) { 1208 ret = btrfs_previous_item(root, path, key.objectid, 1209 BTRFS_DEV_EXTENT_KEY); 1210 if (ret) 1211 goto out; 1212 leaf = path->nodes[0]; 1213 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1214 extent = btrfs_item_ptr(leaf, path->slots[0], 1215 struct btrfs_dev_extent); 1216 BUG_ON(found_key.offset > start || found_key.offset + 1217 btrfs_dev_extent_length(leaf, extent) < start); 1218 key = found_key; 1219 btrfs_release_path(path); 1220 goto again; 1221 } else if (ret == 0) { 1222 leaf = path->nodes[0]; 1223 extent = btrfs_item_ptr(leaf, path->slots[0], 1224 struct btrfs_dev_extent); 1225 } else { 1226 btrfs_error(root->fs_info, ret, "Slot search failed"); 1227 goto out; 1228 } 1229 1230 if (device->bytes_used > 0) { 1231 u64 len = btrfs_dev_extent_length(leaf, extent); 1232 device->bytes_used -= len; 1233 spin_lock(&root->fs_info->free_chunk_lock); 1234 root->fs_info->free_chunk_space += len; 1235 spin_unlock(&root->fs_info->free_chunk_lock); 1236 } 1237 ret = btrfs_del_item(trans, root, path); 1238 if (ret) { 1239 btrfs_error(root->fs_info, ret, 1240 "Failed to remove dev extent item"); 1241 } 1242 out: 1243 btrfs_free_path(path); 1244 return ret; 1245 } 1246 1247 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, 1248 struct btrfs_device *device, 1249 u64 chunk_tree, u64 chunk_objectid, 1250 u64 chunk_offset, u64 start, u64 num_bytes) 1251 { 1252 int ret; 1253 struct btrfs_path *path; 1254 struct btrfs_root *root = device->dev_root; 1255 struct btrfs_dev_extent *extent; 1256 struct extent_buffer *leaf; 1257 struct btrfs_key key; 1258 1259 WARN_ON(!device->in_fs_metadata); 1260 WARN_ON(device->is_tgtdev_for_dev_replace); 1261 path = btrfs_alloc_path(); 1262 if (!path) 1263 return -ENOMEM; 1264 1265 key.objectid = device->devid; 1266 key.offset = start; 1267 key.type = BTRFS_DEV_EXTENT_KEY; 1268 ret = btrfs_insert_empty_item(trans, root, path, &key, 1269 sizeof(*extent)); 1270 if (ret) 1271 goto out; 1272 1273 leaf = path->nodes[0]; 1274 extent = btrfs_item_ptr(leaf, path->slots[0], 1275 struct btrfs_dev_extent); 1276 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree); 1277 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid); 1278 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); 1279 1280 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 1281 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent), 1282 BTRFS_UUID_SIZE); 1283 1284 btrfs_set_dev_extent_length(leaf, extent, num_bytes); 1285 btrfs_mark_buffer_dirty(leaf); 1286 out: 1287 btrfs_free_path(path); 1288 return ret; 1289 } 1290 1291 static u64 find_next_chunk(struct btrfs_fs_info *fs_info) 1292 { 1293 struct extent_map_tree *em_tree; 1294 struct extent_map *em; 1295 struct rb_node *n; 1296 u64 ret = 0; 1297 1298 em_tree = &fs_info->mapping_tree.map_tree; 1299 read_lock(&em_tree->lock); 1300 n = rb_last(&em_tree->map); 1301 if (n) { 1302 em = rb_entry(n, struct extent_map, rb_node); 1303 ret = em->start + em->len; 1304 } 1305 read_unlock(&em_tree->lock); 1306 1307 return ret; 1308 } 1309 1310 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid) 1311 { 1312 int ret; 1313 struct btrfs_key key; 1314 struct btrfs_key found_key; 1315 struct btrfs_path *path; 1316 1317 root = root->fs_info->chunk_root; 1318 1319 path = btrfs_alloc_path(); 1320 if (!path) 1321 return -ENOMEM; 1322 1323 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1324 key.type = BTRFS_DEV_ITEM_KEY; 1325 key.offset = (u64)-1; 1326 1327 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1328 if (ret < 0) 1329 goto error; 1330 1331 BUG_ON(ret == 0); /* Corruption */ 1332 1333 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID, 1334 BTRFS_DEV_ITEM_KEY); 1335 if (ret) { 1336 *objectid = 1; 1337 } else { 1338 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1339 path->slots[0]); 1340 *objectid = found_key.offset + 1; 1341 } 1342 ret = 0; 1343 error: 1344 btrfs_free_path(path); 1345 return ret; 1346 } 1347 1348 /* 1349 * the device information is stored in the chunk root 1350 * the btrfs_device struct should be fully filled in 1351 */ 1352 static int btrfs_add_device(struct btrfs_trans_handle *trans, 1353 struct btrfs_root *root, 1354 struct btrfs_device *device) 1355 { 1356 int ret; 1357 struct btrfs_path *path; 1358 struct btrfs_dev_item *dev_item; 1359 struct extent_buffer *leaf; 1360 struct btrfs_key key; 1361 unsigned long ptr; 1362 1363 root = root->fs_info->chunk_root; 1364 1365 path = btrfs_alloc_path(); 1366 if (!path) 1367 return -ENOMEM; 1368 1369 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1370 key.type = BTRFS_DEV_ITEM_KEY; 1371 key.offset = device->devid; 1372 1373 ret = btrfs_insert_empty_item(trans, root, path, &key, 1374 sizeof(*dev_item)); 1375 if (ret) 1376 goto out; 1377 1378 leaf = path->nodes[0]; 1379 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 1380 1381 btrfs_set_device_id(leaf, dev_item, device->devid); 1382 btrfs_set_device_generation(leaf, dev_item, 0); 1383 btrfs_set_device_type(leaf, dev_item, device->type); 1384 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 1385 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 1386 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 1387 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); 1388 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 1389 btrfs_set_device_group(leaf, dev_item, 0); 1390 btrfs_set_device_seek_speed(leaf, dev_item, 0); 1391 btrfs_set_device_bandwidth(leaf, dev_item, 0); 1392 btrfs_set_device_start_offset(leaf, dev_item, 0); 1393 1394 ptr = (unsigned long)btrfs_device_uuid(dev_item); 1395 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 1396 ptr = (unsigned long)btrfs_device_fsid(dev_item); 1397 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE); 1398 btrfs_mark_buffer_dirty(leaf); 1399 1400 ret = 0; 1401 out: 1402 btrfs_free_path(path); 1403 return ret; 1404 } 1405 1406 static int btrfs_rm_dev_item(struct btrfs_root *root, 1407 struct btrfs_device *device) 1408 { 1409 int ret; 1410 struct btrfs_path *path; 1411 struct btrfs_key key; 1412 struct btrfs_trans_handle *trans; 1413 1414 root = root->fs_info->chunk_root; 1415 1416 path = btrfs_alloc_path(); 1417 if (!path) 1418 return -ENOMEM; 1419 1420 trans = btrfs_start_transaction(root, 0); 1421 if (IS_ERR(trans)) { 1422 btrfs_free_path(path); 1423 return PTR_ERR(trans); 1424 } 1425 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1426 key.type = BTRFS_DEV_ITEM_KEY; 1427 key.offset = device->devid; 1428 lock_chunks(root); 1429 1430 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1431 if (ret < 0) 1432 goto out; 1433 1434 if (ret > 0) { 1435 ret = -ENOENT; 1436 goto out; 1437 } 1438 1439 ret = btrfs_del_item(trans, root, path); 1440 if (ret) 1441 goto out; 1442 out: 1443 btrfs_free_path(path); 1444 unlock_chunks(root); 1445 btrfs_commit_transaction(trans, root); 1446 return ret; 1447 } 1448 1449 int btrfs_rm_device(struct btrfs_root *root, char *device_path) 1450 { 1451 struct btrfs_device *device; 1452 struct btrfs_device *next_device; 1453 struct block_device *bdev; 1454 struct buffer_head *bh = NULL; 1455 struct btrfs_super_block *disk_super; 1456 struct btrfs_fs_devices *cur_devices; 1457 u64 all_avail; 1458 u64 devid; 1459 u64 num_devices; 1460 u8 *dev_uuid; 1461 unsigned seq; 1462 int ret = 0; 1463 bool clear_super = false; 1464 1465 mutex_lock(&uuid_mutex); 1466 1467 do { 1468 seq = read_seqbegin(&root->fs_info->profiles_lock); 1469 1470 all_avail = root->fs_info->avail_data_alloc_bits | 1471 root->fs_info->avail_system_alloc_bits | 1472 root->fs_info->avail_metadata_alloc_bits; 1473 } while (read_seqretry(&root->fs_info->profiles_lock, seq)); 1474 1475 num_devices = root->fs_info->fs_devices->num_devices; 1476 btrfs_dev_replace_lock(&root->fs_info->dev_replace); 1477 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) { 1478 WARN_ON(num_devices < 1); 1479 num_devices--; 1480 } 1481 btrfs_dev_replace_unlock(&root->fs_info->dev_replace); 1482 1483 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) { 1484 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET; 1485 goto out; 1486 } 1487 1488 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) { 1489 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET; 1490 goto out; 1491 } 1492 1493 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) && 1494 root->fs_info->fs_devices->rw_devices <= 2) { 1495 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET; 1496 goto out; 1497 } 1498 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) && 1499 root->fs_info->fs_devices->rw_devices <= 3) { 1500 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET; 1501 goto out; 1502 } 1503 1504 if (strcmp(device_path, "missing") == 0) { 1505 struct list_head *devices; 1506 struct btrfs_device *tmp; 1507 1508 device = NULL; 1509 devices = &root->fs_info->fs_devices->devices; 1510 /* 1511 * It is safe to read the devices since the volume_mutex 1512 * is held. 1513 */ 1514 list_for_each_entry(tmp, devices, dev_list) { 1515 if (tmp->in_fs_metadata && 1516 !tmp->is_tgtdev_for_dev_replace && 1517 !tmp->bdev) { 1518 device = tmp; 1519 break; 1520 } 1521 } 1522 bdev = NULL; 1523 bh = NULL; 1524 disk_super = NULL; 1525 if (!device) { 1526 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND; 1527 goto out; 1528 } 1529 } else { 1530 ret = btrfs_get_bdev_and_sb(device_path, 1531 FMODE_WRITE | FMODE_EXCL, 1532 root->fs_info->bdev_holder, 0, 1533 &bdev, &bh); 1534 if (ret) 1535 goto out; 1536 disk_super = (struct btrfs_super_block *)bh->b_data; 1537 devid = btrfs_stack_device_id(&disk_super->dev_item); 1538 dev_uuid = disk_super->dev_item.uuid; 1539 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1540 disk_super->fsid); 1541 if (!device) { 1542 ret = -ENOENT; 1543 goto error_brelse; 1544 } 1545 } 1546 1547 if (device->is_tgtdev_for_dev_replace) { 1548 ret = BTRFS_ERROR_DEV_TGT_REPLACE; 1549 goto error_brelse; 1550 } 1551 1552 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) { 1553 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE; 1554 goto error_brelse; 1555 } 1556 1557 if (device->writeable) { 1558 lock_chunks(root); 1559 list_del_init(&device->dev_alloc_list); 1560 unlock_chunks(root); 1561 root->fs_info->fs_devices->rw_devices--; 1562 clear_super = true; 1563 } 1564 1565 ret = btrfs_shrink_device(device, 0); 1566 if (ret) 1567 goto error_undo; 1568 1569 /* 1570 * TODO: the superblock still includes this device in its num_devices 1571 * counter although write_all_supers() is not locked out. This 1572 * could give a filesystem state which requires a degraded mount. 1573 */ 1574 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); 1575 if (ret) 1576 goto error_undo; 1577 1578 spin_lock(&root->fs_info->free_chunk_lock); 1579 root->fs_info->free_chunk_space = device->total_bytes - 1580 device->bytes_used; 1581 spin_unlock(&root->fs_info->free_chunk_lock); 1582 1583 device->in_fs_metadata = 0; 1584 btrfs_scrub_cancel_dev(root->fs_info, device); 1585 1586 /* 1587 * the device list mutex makes sure that we don't change 1588 * the device list while someone else is writing out all 1589 * the device supers. 1590 */ 1591 1592 cur_devices = device->fs_devices; 1593 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1594 list_del_rcu(&device->dev_list); 1595 1596 device->fs_devices->num_devices--; 1597 device->fs_devices->total_devices--; 1598 1599 if (device->missing) 1600 root->fs_info->fs_devices->missing_devices--; 1601 1602 next_device = list_entry(root->fs_info->fs_devices->devices.next, 1603 struct btrfs_device, dev_list); 1604 if (device->bdev == root->fs_info->sb->s_bdev) 1605 root->fs_info->sb->s_bdev = next_device->bdev; 1606 if (device->bdev == root->fs_info->fs_devices->latest_bdev) 1607 root->fs_info->fs_devices->latest_bdev = next_device->bdev; 1608 1609 if (device->bdev) 1610 device->fs_devices->open_devices--; 1611 1612 call_rcu(&device->rcu, free_device); 1613 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1614 1615 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1; 1616 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices); 1617 1618 if (cur_devices->open_devices == 0) { 1619 struct btrfs_fs_devices *fs_devices; 1620 fs_devices = root->fs_info->fs_devices; 1621 while (fs_devices) { 1622 if (fs_devices->seed == cur_devices) 1623 break; 1624 fs_devices = fs_devices->seed; 1625 } 1626 fs_devices->seed = cur_devices->seed; 1627 cur_devices->seed = NULL; 1628 lock_chunks(root); 1629 __btrfs_close_devices(cur_devices); 1630 unlock_chunks(root); 1631 free_fs_devices(cur_devices); 1632 } 1633 1634 root->fs_info->num_tolerated_disk_barrier_failures = 1635 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 1636 1637 /* 1638 * at this point, the device is zero sized. We want to 1639 * remove it from the devices list and zero out the old super 1640 */ 1641 if (clear_super && disk_super) { 1642 /* make sure this device isn't detected as part of 1643 * the FS anymore 1644 */ 1645 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 1646 set_buffer_dirty(bh); 1647 sync_dirty_buffer(bh); 1648 } 1649 1650 ret = 0; 1651 1652 /* Notify udev that device has changed */ 1653 if (bdev) 1654 btrfs_kobject_uevent(bdev, KOBJ_CHANGE); 1655 1656 error_brelse: 1657 brelse(bh); 1658 if (bdev) 1659 blkdev_put(bdev, FMODE_READ | FMODE_EXCL); 1660 out: 1661 mutex_unlock(&uuid_mutex); 1662 return ret; 1663 error_undo: 1664 if (device->writeable) { 1665 lock_chunks(root); 1666 list_add(&device->dev_alloc_list, 1667 &root->fs_info->fs_devices->alloc_list); 1668 unlock_chunks(root); 1669 root->fs_info->fs_devices->rw_devices++; 1670 } 1671 goto error_brelse; 1672 } 1673 1674 void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info, 1675 struct btrfs_device *srcdev) 1676 { 1677 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex)); 1678 list_del_rcu(&srcdev->dev_list); 1679 list_del_rcu(&srcdev->dev_alloc_list); 1680 fs_info->fs_devices->num_devices--; 1681 if (srcdev->missing) { 1682 fs_info->fs_devices->missing_devices--; 1683 fs_info->fs_devices->rw_devices++; 1684 } 1685 if (srcdev->can_discard) 1686 fs_info->fs_devices->num_can_discard--; 1687 if (srcdev->bdev) 1688 fs_info->fs_devices->open_devices--; 1689 1690 call_rcu(&srcdev->rcu, free_device); 1691 } 1692 1693 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 1694 struct btrfs_device *tgtdev) 1695 { 1696 struct btrfs_device *next_device; 1697 1698 WARN_ON(!tgtdev); 1699 mutex_lock(&fs_info->fs_devices->device_list_mutex); 1700 if (tgtdev->bdev) { 1701 btrfs_scratch_superblock(tgtdev); 1702 fs_info->fs_devices->open_devices--; 1703 } 1704 fs_info->fs_devices->num_devices--; 1705 if (tgtdev->can_discard) 1706 fs_info->fs_devices->num_can_discard++; 1707 1708 next_device = list_entry(fs_info->fs_devices->devices.next, 1709 struct btrfs_device, dev_list); 1710 if (tgtdev->bdev == fs_info->sb->s_bdev) 1711 fs_info->sb->s_bdev = next_device->bdev; 1712 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev) 1713 fs_info->fs_devices->latest_bdev = next_device->bdev; 1714 list_del_rcu(&tgtdev->dev_list); 1715 1716 call_rcu(&tgtdev->rcu, free_device); 1717 1718 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 1719 } 1720 1721 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path, 1722 struct btrfs_device **device) 1723 { 1724 int ret = 0; 1725 struct btrfs_super_block *disk_super; 1726 u64 devid; 1727 u8 *dev_uuid; 1728 struct block_device *bdev; 1729 struct buffer_head *bh; 1730 1731 *device = NULL; 1732 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ, 1733 root->fs_info->bdev_holder, 0, &bdev, &bh); 1734 if (ret) 1735 return ret; 1736 disk_super = (struct btrfs_super_block *)bh->b_data; 1737 devid = btrfs_stack_device_id(&disk_super->dev_item); 1738 dev_uuid = disk_super->dev_item.uuid; 1739 *device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1740 disk_super->fsid); 1741 brelse(bh); 1742 if (!*device) 1743 ret = -ENOENT; 1744 blkdev_put(bdev, FMODE_READ); 1745 return ret; 1746 } 1747 1748 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root, 1749 char *device_path, 1750 struct btrfs_device **device) 1751 { 1752 *device = NULL; 1753 if (strcmp(device_path, "missing") == 0) { 1754 struct list_head *devices; 1755 struct btrfs_device *tmp; 1756 1757 devices = &root->fs_info->fs_devices->devices; 1758 /* 1759 * It is safe to read the devices since the volume_mutex 1760 * is held by the caller. 1761 */ 1762 list_for_each_entry(tmp, devices, dev_list) { 1763 if (tmp->in_fs_metadata && !tmp->bdev) { 1764 *device = tmp; 1765 break; 1766 } 1767 } 1768 1769 if (!*device) { 1770 pr_err("btrfs: no missing device found\n"); 1771 return -ENOENT; 1772 } 1773 1774 return 0; 1775 } else { 1776 return btrfs_find_device_by_path(root, device_path, device); 1777 } 1778 } 1779 1780 /* 1781 * does all the dirty work required for changing file system's UUID. 1782 */ 1783 static int btrfs_prepare_sprout(struct btrfs_root *root) 1784 { 1785 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 1786 struct btrfs_fs_devices *old_devices; 1787 struct btrfs_fs_devices *seed_devices; 1788 struct btrfs_super_block *disk_super = root->fs_info->super_copy; 1789 struct btrfs_device *device; 1790 u64 super_flags; 1791 1792 BUG_ON(!mutex_is_locked(&uuid_mutex)); 1793 if (!fs_devices->seeding) 1794 return -EINVAL; 1795 1796 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 1797 if (!seed_devices) 1798 return -ENOMEM; 1799 1800 old_devices = clone_fs_devices(fs_devices); 1801 if (IS_ERR(old_devices)) { 1802 kfree(seed_devices); 1803 return PTR_ERR(old_devices); 1804 } 1805 1806 list_add(&old_devices->list, &fs_uuids); 1807 1808 memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); 1809 seed_devices->opened = 1; 1810 INIT_LIST_HEAD(&seed_devices->devices); 1811 INIT_LIST_HEAD(&seed_devices->alloc_list); 1812 mutex_init(&seed_devices->device_list_mutex); 1813 1814 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1815 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, 1816 synchronize_rcu); 1817 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1818 1819 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); 1820 list_for_each_entry(device, &seed_devices->devices, dev_list) { 1821 device->fs_devices = seed_devices; 1822 } 1823 1824 fs_devices->seeding = 0; 1825 fs_devices->num_devices = 0; 1826 fs_devices->open_devices = 0; 1827 fs_devices->total_devices = 0; 1828 fs_devices->seed = seed_devices; 1829 1830 generate_random_uuid(fs_devices->fsid); 1831 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1832 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1833 super_flags = btrfs_super_flags(disk_super) & 1834 ~BTRFS_SUPER_FLAG_SEEDING; 1835 btrfs_set_super_flags(disk_super, super_flags); 1836 1837 return 0; 1838 } 1839 1840 /* 1841 * strore the expected generation for seed devices in device items. 1842 */ 1843 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans, 1844 struct btrfs_root *root) 1845 { 1846 struct btrfs_path *path; 1847 struct extent_buffer *leaf; 1848 struct btrfs_dev_item *dev_item; 1849 struct btrfs_device *device; 1850 struct btrfs_key key; 1851 u8 fs_uuid[BTRFS_UUID_SIZE]; 1852 u8 dev_uuid[BTRFS_UUID_SIZE]; 1853 u64 devid; 1854 int ret; 1855 1856 path = btrfs_alloc_path(); 1857 if (!path) 1858 return -ENOMEM; 1859 1860 root = root->fs_info->chunk_root; 1861 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1862 key.offset = 0; 1863 key.type = BTRFS_DEV_ITEM_KEY; 1864 1865 while (1) { 1866 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 1867 if (ret < 0) 1868 goto error; 1869 1870 leaf = path->nodes[0]; 1871 next_slot: 1872 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1873 ret = btrfs_next_leaf(root, path); 1874 if (ret > 0) 1875 break; 1876 if (ret < 0) 1877 goto error; 1878 leaf = path->nodes[0]; 1879 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1880 btrfs_release_path(path); 1881 continue; 1882 } 1883 1884 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1885 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || 1886 key.type != BTRFS_DEV_ITEM_KEY) 1887 break; 1888 1889 dev_item = btrfs_item_ptr(leaf, path->slots[0], 1890 struct btrfs_dev_item); 1891 devid = btrfs_device_id(leaf, dev_item); 1892 read_extent_buffer(leaf, dev_uuid, 1893 (unsigned long)btrfs_device_uuid(dev_item), 1894 BTRFS_UUID_SIZE); 1895 read_extent_buffer(leaf, fs_uuid, 1896 (unsigned long)btrfs_device_fsid(dev_item), 1897 BTRFS_UUID_SIZE); 1898 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1899 fs_uuid); 1900 BUG_ON(!device); /* Logic error */ 1901 1902 if (device->fs_devices->seeding) { 1903 btrfs_set_device_generation(leaf, dev_item, 1904 device->generation); 1905 btrfs_mark_buffer_dirty(leaf); 1906 } 1907 1908 path->slots[0]++; 1909 goto next_slot; 1910 } 1911 ret = 0; 1912 error: 1913 btrfs_free_path(path); 1914 return ret; 1915 } 1916 1917 int btrfs_init_new_device(struct btrfs_root *root, char *device_path) 1918 { 1919 struct request_queue *q; 1920 struct btrfs_trans_handle *trans; 1921 struct btrfs_device *device; 1922 struct block_device *bdev; 1923 struct list_head *devices; 1924 struct super_block *sb = root->fs_info->sb; 1925 struct rcu_string *name; 1926 u64 total_bytes; 1927 int seeding_dev = 0; 1928 int ret = 0; 1929 1930 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) 1931 return -EROFS; 1932 1933 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 1934 root->fs_info->bdev_holder); 1935 if (IS_ERR(bdev)) 1936 return PTR_ERR(bdev); 1937 1938 if (root->fs_info->fs_devices->seeding) { 1939 seeding_dev = 1; 1940 down_write(&sb->s_umount); 1941 mutex_lock(&uuid_mutex); 1942 } 1943 1944 filemap_write_and_wait(bdev->bd_inode->i_mapping); 1945 1946 devices = &root->fs_info->fs_devices->devices; 1947 1948 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1949 list_for_each_entry(device, devices, dev_list) { 1950 if (device->bdev == bdev) { 1951 ret = -EEXIST; 1952 mutex_unlock( 1953 &root->fs_info->fs_devices->device_list_mutex); 1954 goto error; 1955 } 1956 } 1957 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1958 1959 device = kzalloc(sizeof(*device), GFP_NOFS); 1960 if (!device) { 1961 /* we can safely leave the fs_devices entry around */ 1962 ret = -ENOMEM; 1963 goto error; 1964 } 1965 1966 name = rcu_string_strdup(device_path, GFP_NOFS); 1967 if (!name) { 1968 kfree(device); 1969 ret = -ENOMEM; 1970 goto error; 1971 } 1972 rcu_assign_pointer(device->name, name); 1973 1974 ret = find_next_devid(root, &device->devid); 1975 if (ret) { 1976 rcu_string_free(device->name); 1977 kfree(device); 1978 goto error; 1979 } 1980 1981 trans = btrfs_start_transaction(root, 0); 1982 if (IS_ERR(trans)) { 1983 rcu_string_free(device->name); 1984 kfree(device); 1985 ret = PTR_ERR(trans); 1986 goto error; 1987 } 1988 1989 lock_chunks(root); 1990 1991 q = bdev_get_queue(bdev); 1992 if (blk_queue_discard(q)) 1993 device->can_discard = 1; 1994 device->writeable = 1; 1995 device->work.func = pending_bios_fn; 1996 generate_random_uuid(device->uuid); 1997 spin_lock_init(&device->io_lock); 1998 device->generation = trans->transid; 1999 device->io_width = root->sectorsize; 2000 device->io_align = root->sectorsize; 2001 device->sector_size = root->sectorsize; 2002 device->total_bytes = i_size_read(bdev->bd_inode); 2003 device->disk_total_bytes = device->total_bytes; 2004 device->dev_root = root->fs_info->dev_root; 2005 device->bdev = bdev; 2006 device->in_fs_metadata = 1; 2007 device->is_tgtdev_for_dev_replace = 0; 2008 device->mode = FMODE_EXCL; 2009 set_blocksize(device->bdev, 4096); 2010 2011 if (seeding_dev) { 2012 sb->s_flags &= ~MS_RDONLY; 2013 ret = btrfs_prepare_sprout(root); 2014 BUG_ON(ret); /* -ENOMEM */ 2015 } 2016 2017 device->fs_devices = root->fs_info->fs_devices; 2018 2019 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2020 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices); 2021 list_add(&device->dev_alloc_list, 2022 &root->fs_info->fs_devices->alloc_list); 2023 root->fs_info->fs_devices->num_devices++; 2024 root->fs_info->fs_devices->open_devices++; 2025 root->fs_info->fs_devices->rw_devices++; 2026 root->fs_info->fs_devices->total_devices++; 2027 if (device->can_discard) 2028 root->fs_info->fs_devices->num_can_discard++; 2029 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes; 2030 2031 spin_lock(&root->fs_info->free_chunk_lock); 2032 root->fs_info->free_chunk_space += device->total_bytes; 2033 spin_unlock(&root->fs_info->free_chunk_lock); 2034 2035 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 2036 root->fs_info->fs_devices->rotating = 1; 2037 2038 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); 2039 btrfs_set_super_total_bytes(root->fs_info->super_copy, 2040 total_bytes + device->total_bytes); 2041 2042 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy); 2043 btrfs_set_super_num_devices(root->fs_info->super_copy, 2044 total_bytes + 1); 2045 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2046 2047 if (seeding_dev) { 2048 ret = init_first_rw_device(trans, root, device); 2049 if (ret) { 2050 btrfs_abort_transaction(trans, root, ret); 2051 goto error_trans; 2052 } 2053 ret = btrfs_finish_sprout(trans, root); 2054 if (ret) { 2055 btrfs_abort_transaction(trans, root, ret); 2056 goto error_trans; 2057 } 2058 } else { 2059 ret = btrfs_add_device(trans, root, device); 2060 if (ret) { 2061 btrfs_abort_transaction(trans, root, ret); 2062 goto error_trans; 2063 } 2064 } 2065 2066 /* 2067 * we've got more storage, clear any full flags on the space 2068 * infos 2069 */ 2070 btrfs_clear_space_info_full(root->fs_info); 2071 2072 unlock_chunks(root); 2073 root->fs_info->num_tolerated_disk_barrier_failures = 2074 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 2075 ret = btrfs_commit_transaction(trans, root); 2076 2077 if (seeding_dev) { 2078 mutex_unlock(&uuid_mutex); 2079 up_write(&sb->s_umount); 2080 2081 if (ret) /* transaction commit */ 2082 return ret; 2083 2084 ret = btrfs_relocate_sys_chunks(root); 2085 if (ret < 0) 2086 btrfs_error(root->fs_info, ret, 2087 "Failed to relocate sys chunks after " 2088 "device initialization. This can be fixed " 2089 "using the \"btrfs balance\" command."); 2090 trans = btrfs_attach_transaction(root); 2091 if (IS_ERR(trans)) { 2092 if (PTR_ERR(trans) == -ENOENT) 2093 return 0; 2094 return PTR_ERR(trans); 2095 } 2096 ret = btrfs_commit_transaction(trans, root); 2097 } 2098 2099 return ret; 2100 2101 error_trans: 2102 unlock_chunks(root); 2103 btrfs_end_transaction(trans, root); 2104 rcu_string_free(device->name); 2105 kfree(device); 2106 error: 2107 blkdev_put(bdev, FMODE_EXCL); 2108 if (seeding_dev) { 2109 mutex_unlock(&uuid_mutex); 2110 up_write(&sb->s_umount); 2111 } 2112 return ret; 2113 } 2114 2115 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path, 2116 struct btrfs_device **device_out) 2117 { 2118 struct request_queue *q; 2119 struct btrfs_device *device; 2120 struct block_device *bdev; 2121 struct btrfs_fs_info *fs_info = root->fs_info; 2122 struct list_head *devices; 2123 struct rcu_string *name; 2124 int ret = 0; 2125 2126 *device_out = NULL; 2127 if (fs_info->fs_devices->seeding) 2128 return -EINVAL; 2129 2130 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 2131 fs_info->bdev_holder); 2132 if (IS_ERR(bdev)) 2133 return PTR_ERR(bdev); 2134 2135 filemap_write_and_wait(bdev->bd_inode->i_mapping); 2136 2137 devices = &fs_info->fs_devices->devices; 2138 list_for_each_entry(device, devices, dev_list) { 2139 if (device->bdev == bdev) { 2140 ret = -EEXIST; 2141 goto error; 2142 } 2143 } 2144 2145 device = kzalloc(sizeof(*device), GFP_NOFS); 2146 if (!device) { 2147 ret = -ENOMEM; 2148 goto error; 2149 } 2150 2151 name = rcu_string_strdup(device_path, GFP_NOFS); 2152 if (!name) { 2153 kfree(device); 2154 ret = -ENOMEM; 2155 goto error; 2156 } 2157 rcu_assign_pointer(device->name, name); 2158 2159 q = bdev_get_queue(bdev); 2160 if (blk_queue_discard(q)) 2161 device->can_discard = 1; 2162 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2163 device->writeable = 1; 2164 device->work.func = pending_bios_fn; 2165 generate_random_uuid(device->uuid); 2166 device->devid = BTRFS_DEV_REPLACE_DEVID; 2167 spin_lock_init(&device->io_lock); 2168 device->generation = 0; 2169 device->io_width = root->sectorsize; 2170 device->io_align = root->sectorsize; 2171 device->sector_size = root->sectorsize; 2172 device->total_bytes = i_size_read(bdev->bd_inode); 2173 device->disk_total_bytes = device->total_bytes; 2174 device->dev_root = fs_info->dev_root; 2175 device->bdev = bdev; 2176 device->in_fs_metadata = 1; 2177 device->is_tgtdev_for_dev_replace = 1; 2178 device->mode = FMODE_EXCL; 2179 set_blocksize(device->bdev, 4096); 2180 device->fs_devices = fs_info->fs_devices; 2181 list_add(&device->dev_list, &fs_info->fs_devices->devices); 2182 fs_info->fs_devices->num_devices++; 2183 fs_info->fs_devices->open_devices++; 2184 if (device->can_discard) 2185 fs_info->fs_devices->num_can_discard++; 2186 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2187 2188 *device_out = device; 2189 return ret; 2190 2191 error: 2192 blkdev_put(bdev, FMODE_EXCL); 2193 return ret; 2194 } 2195 2196 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, 2197 struct btrfs_device *tgtdev) 2198 { 2199 WARN_ON(fs_info->fs_devices->rw_devices == 0); 2200 tgtdev->io_width = fs_info->dev_root->sectorsize; 2201 tgtdev->io_align = fs_info->dev_root->sectorsize; 2202 tgtdev->sector_size = fs_info->dev_root->sectorsize; 2203 tgtdev->dev_root = fs_info->dev_root; 2204 tgtdev->in_fs_metadata = 1; 2205 } 2206 2207 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, 2208 struct btrfs_device *device) 2209 { 2210 int ret; 2211 struct btrfs_path *path; 2212 struct btrfs_root *root; 2213 struct btrfs_dev_item *dev_item; 2214 struct extent_buffer *leaf; 2215 struct btrfs_key key; 2216 2217 root = device->dev_root->fs_info->chunk_root; 2218 2219 path = btrfs_alloc_path(); 2220 if (!path) 2221 return -ENOMEM; 2222 2223 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 2224 key.type = BTRFS_DEV_ITEM_KEY; 2225 key.offset = device->devid; 2226 2227 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2228 if (ret < 0) 2229 goto out; 2230 2231 if (ret > 0) { 2232 ret = -ENOENT; 2233 goto out; 2234 } 2235 2236 leaf = path->nodes[0]; 2237 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 2238 2239 btrfs_set_device_id(leaf, dev_item, device->devid); 2240 btrfs_set_device_type(leaf, dev_item, device->type); 2241 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 2242 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 2243 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 2244 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes); 2245 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 2246 btrfs_mark_buffer_dirty(leaf); 2247 2248 out: 2249 btrfs_free_path(path); 2250 return ret; 2251 } 2252 2253 static int __btrfs_grow_device(struct btrfs_trans_handle *trans, 2254 struct btrfs_device *device, u64 new_size) 2255 { 2256 struct btrfs_super_block *super_copy = 2257 device->dev_root->fs_info->super_copy; 2258 u64 old_total = btrfs_super_total_bytes(super_copy); 2259 u64 diff = new_size - device->total_bytes; 2260 2261 if (!device->writeable) 2262 return -EACCES; 2263 if (new_size <= device->total_bytes || 2264 device->is_tgtdev_for_dev_replace) 2265 return -EINVAL; 2266 2267 btrfs_set_super_total_bytes(super_copy, old_total + diff); 2268 device->fs_devices->total_rw_bytes += diff; 2269 2270 device->total_bytes = new_size; 2271 device->disk_total_bytes = new_size; 2272 btrfs_clear_space_info_full(device->dev_root->fs_info); 2273 2274 return btrfs_update_device(trans, device); 2275 } 2276 2277 int btrfs_grow_device(struct btrfs_trans_handle *trans, 2278 struct btrfs_device *device, u64 new_size) 2279 { 2280 int ret; 2281 lock_chunks(device->dev_root); 2282 ret = __btrfs_grow_device(trans, device, new_size); 2283 unlock_chunks(device->dev_root); 2284 return ret; 2285 } 2286 2287 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, 2288 struct btrfs_root *root, 2289 u64 chunk_tree, u64 chunk_objectid, 2290 u64 chunk_offset) 2291 { 2292 int ret; 2293 struct btrfs_path *path; 2294 struct btrfs_key key; 2295 2296 root = root->fs_info->chunk_root; 2297 path = btrfs_alloc_path(); 2298 if (!path) 2299 return -ENOMEM; 2300 2301 key.objectid = chunk_objectid; 2302 key.offset = chunk_offset; 2303 key.type = BTRFS_CHUNK_ITEM_KEY; 2304 2305 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2306 if (ret < 0) 2307 goto out; 2308 else if (ret > 0) { /* Logic error or corruption */ 2309 btrfs_error(root->fs_info, -ENOENT, 2310 "Failed lookup while freeing chunk."); 2311 ret = -ENOENT; 2312 goto out; 2313 } 2314 2315 ret = btrfs_del_item(trans, root, path); 2316 if (ret < 0) 2317 btrfs_error(root->fs_info, ret, 2318 "Failed to delete chunk item."); 2319 out: 2320 btrfs_free_path(path); 2321 return ret; 2322 } 2323 2324 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 2325 chunk_offset) 2326 { 2327 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 2328 struct btrfs_disk_key *disk_key; 2329 struct btrfs_chunk *chunk; 2330 u8 *ptr; 2331 int ret = 0; 2332 u32 num_stripes; 2333 u32 array_size; 2334 u32 len = 0; 2335 u32 cur; 2336 struct btrfs_key key; 2337 2338 array_size = btrfs_super_sys_array_size(super_copy); 2339 2340 ptr = super_copy->sys_chunk_array; 2341 cur = 0; 2342 2343 while (cur < array_size) { 2344 disk_key = (struct btrfs_disk_key *)ptr; 2345 btrfs_disk_key_to_cpu(&key, disk_key); 2346 2347 len = sizeof(*disk_key); 2348 2349 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 2350 chunk = (struct btrfs_chunk *)(ptr + len); 2351 num_stripes = btrfs_stack_chunk_num_stripes(chunk); 2352 len += btrfs_chunk_item_size(num_stripes); 2353 } else { 2354 ret = -EIO; 2355 break; 2356 } 2357 if (key.objectid == chunk_objectid && 2358 key.offset == chunk_offset) { 2359 memmove(ptr, ptr + len, array_size - (cur + len)); 2360 array_size -= len; 2361 btrfs_set_super_sys_array_size(super_copy, array_size); 2362 } else { 2363 ptr += len; 2364 cur += len; 2365 } 2366 } 2367 return ret; 2368 } 2369 2370 static int btrfs_relocate_chunk(struct btrfs_root *root, 2371 u64 chunk_tree, u64 chunk_objectid, 2372 u64 chunk_offset) 2373 { 2374 struct extent_map_tree *em_tree; 2375 struct btrfs_root *extent_root; 2376 struct btrfs_trans_handle *trans; 2377 struct extent_map *em; 2378 struct map_lookup *map; 2379 int ret; 2380 int i; 2381 2382 root = root->fs_info->chunk_root; 2383 extent_root = root->fs_info->extent_root; 2384 em_tree = &root->fs_info->mapping_tree.map_tree; 2385 2386 ret = btrfs_can_relocate(extent_root, chunk_offset); 2387 if (ret) 2388 return -ENOSPC; 2389 2390 /* step one, relocate all the extents inside this chunk */ 2391 ret = btrfs_relocate_block_group(extent_root, chunk_offset); 2392 if (ret) 2393 return ret; 2394 2395 trans = btrfs_start_transaction(root, 0); 2396 if (IS_ERR(trans)) { 2397 ret = PTR_ERR(trans); 2398 btrfs_std_error(root->fs_info, ret); 2399 return ret; 2400 } 2401 2402 lock_chunks(root); 2403 2404 /* 2405 * step two, delete the device extents and the 2406 * chunk tree entries 2407 */ 2408 read_lock(&em_tree->lock); 2409 em = lookup_extent_mapping(em_tree, chunk_offset, 1); 2410 read_unlock(&em_tree->lock); 2411 2412 BUG_ON(!em || em->start > chunk_offset || 2413 em->start + em->len < chunk_offset); 2414 map = (struct map_lookup *)em->bdev; 2415 2416 for (i = 0; i < map->num_stripes; i++) { 2417 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, 2418 map->stripes[i].physical); 2419 BUG_ON(ret); 2420 2421 if (map->stripes[i].dev) { 2422 ret = btrfs_update_device(trans, map->stripes[i].dev); 2423 BUG_ON(ret); 2424 } 2425 } 2426 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, 2427 chunk_offset); 2428 2429 BUG_ON(ret); 2430 2431 trace_btrfs_chunk_free(root, map, chunk_offset, em->len); 2432 2433 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 2434 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); 2435 BUG_ON(ret); 2436 } 2437 2438 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset); 2439 BUG_ON(ret); 2440 2441 write_lock(&em_tree->lock); 2442 remove_extent_mapping(em_tree, em); 2443 write_unlock(&em_tree->lock); 2444 2445 kfree(map); 2446 em->bdev = NULL; 2447 2448 /* once for the tree */ 2449 free_extent_map(em); 2450 /* once for us */ 2451 free_extent_map(em); 2452 2453 unlock_chunks(root); 2454 btrfs_end_transaction(trans, root); 2455 return 0; 2456 } 2457 2458 static int btrfs_relocate_sys_chunks(struct btrfs_root *root) 2459 { 2460 struct btrfs_root *chunk_root = root->fs_info->chunk_root; 2461 struct btrfs_path *path; 2462 struct extent_buffer *leaf; 2463 struct btrfs_chunk *chunk; 2464 struct btrfs_key key; 2465 struct btrfs_key found_key; 2466 u64 chunk_tree = chunk_root->root_key.objectid; 2467 u64 chunk_type; 2468 bool retried = false; 2469 int failed = 0; 2470 int ret; 2471 2472 path = btrfs_alloc_path(); 2473 if (!path) 2474 return -ENOMEM; 2475 2476 again: 2477 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2478 key.offset = (u64)-1; 2479 key.type = BTRFS_CHUNK_ITEM_KEY; 2480 2481 while (1) { 2482 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2483 if (ret < 0) 2484 goto error; 2485 BUG_ON(ret == 0); /* Corruption */ 2486 2487 ret = btrfs_previous_item(chunk_root, path, key.objectid, 2488 key.type); 2489 if (ret < 0) 2490 goto error; 2491 if (ret > 0) 2492 break; 2493 2494 leaf = path->nodes[0]; 2495 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2496 2497 chunk = btrfs_item_ptr(leaf, path->slots[0], 2498 struct btrfs_chunk); 2499 chunk_type = btrfs_chunk_type(leaf, chunk); 2500 btrfs_release_path(path); 2501 2502 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { 2503 ret = btrfs_relocate_chunk(chunk_root, chunk_tree, 2504 found_key.objectid, 2505 found_key.offset); 2506 if (ret == -ENOSPC) 2507 failed++; 2508 else if (ret) 2509 BUG(); 2510 } 2511 2512 if (found_key.offset == 0) 2513 break; 2514 key.offset = found_key.offset - 1; 2515 } 2516 ret = 0; 2517 if (failed && !retried) { 2518 failed = 0; 2519 retried = true; 2520 goto again; 2521 } else if (failed && retried) { 2522 WARN_ON(1); 2523 ret = -ENOSPC; 2524 } 2525 error: 2526 btrfs_free_path(path); 2527 return ret; 2528 } 2529 2530 static int insert_balance_item(struct btrfs_root *root, 2531 struct btrfs_balance_control *bctl) 2532 { 2533 struct btrfs_trans_handle *trans; 2534 struct btrfs_balance_item *item; 2535 struct btrfs_disk_balance_args disk_bargs; 2536 struct btrfs_path *path; 2537 struct extent_buffer *leaf; 2538 struct btrfs_key key; 2539 int ret, err; 2540 2541 path = btrfs_alloc_path(); 2542 if (!path) 2543 return -ENOMEM; 2544 2545 trans = btrfs_start_transaction(root, 0); 2546 if (IS_ERR(trans)) { 2547 btrfs_free_path(path); 2548 return PTR_ERR(trans); 2549 } 2550 2551 key.objectid = BTRFS_BALANCE_OBJECTID; 2552 key.type = BTRFS_BALANCE_ITEM_KEY; 2553 key.offset = 0; 2554 2555 ret = btrfs_insert_empty_item(trans, root, path, &key, 2556 sizeof(*item)); 2557 if (ret) 2558 goto out; 2559 2560 leaf = path->nodes[0]; 2561 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 2562 2563 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); 2564 2565 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); 2566 btrfs_set_balance_data(leaf, item, &disk_bargs); 2567 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); 2568 btrfs_set_balance_meta(leaf, item, &disk_bargs); 2569 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); 2570 btrfs_set_balance_sys(leaf, item, &disk_bargs); 2571 2572 btrfs_set_balance_flags(leaf, item, bctl->flags); 2573 2574 btrfs_mark_buffer_dirty(leaf); 2575 out: 2576 btrfs_free_path(path); 2577 err = btrfs_commit_transaction(trans, root); 2578 if (err && !ret) 2579 ret = err; 2580 return ret; 2581 } 2582 2583 static int del_balance_item(struct btrfs_root *root) 2584 { 2585 struct btrfs_trans_handle *trans; 2586 struct btrfs_path *path; 2587 struct btrfs_key key; 2588 int ret, err; 2589 2590 path = btrfs_alloc_path(); 2591 if (!path) 2592 return -ENOMEM; 2593 2594 trans = btrfs_start_transaction(root, 0); 2595 if (IS_ERR(trans)) { 2596 btrfs_free_path(path); 2597 return PTR_ERR(trans); 2598 } 2599 2600 key.objectid = BTRFS_BALANCE_OBJECTID; 2601 key.type = BTRFS_BALANCE_ITEM_KEY; 2602 key.offset = 0; 2603 2604 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2605 if (ret < 0) 2606 goto out; 2607 if (ret > 0) { 2608 ret = -ENOENT; 2609 goto out; 2610 } 2611 2612 ret = btrfs_del_item(trans, root, path); 2613 out: 2614 btrfs_free_path(path); 2615 err = btrfs_commit_transaction(trans, root); 2616 if (err && !ret) 2617 ret = err; 2618 return ret; 2619 } 2620 2621 /* 2622 * This is a heuristic used to reduce the number of chunks balanced on 2623 * resume after balance was interrupted. 2624 */ 2625 static void update_balance_args(struct btrfs_balance_control *bctl) 2626 { 2627 /* 2628 * Turn on soft mode for chunk types that were being converted. 2629 */ 2630 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) 2631 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; 2632 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) 2633 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; 2634 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) 2635 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; 2636 2637 /* 2638 * Turn on usage filter if is not already used. The idea is 2639 * that chunks that we have already balanced should be 2640 * reasonably full. Don't do it for chunks that are being 2641 * converted - that will keep us from relocating unconverted 2642 * (albeit full) chunks. 2643 */ 2644 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && 2645 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2646 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; 2647 bctl->data.usage = 90; 2648 } 2649 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && 2650 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2651 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; 2652 bctl->sys.usage = 90; 2653 } 2654 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && 2655 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2656 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; 2657 bctl->meta.usage = 90; 2658 } 2659 } 2660 2661 /* 2662 * Should be called with both balance and volume mutexes held to 2663 * serialize other volume operations (add_dev/rm_dev/resize) with 2664 * restriper. Same goes for unset_balance_control. 2665 */ 2666 static void set_balance_control(struct btrfs_balance_control *bctl) 2667 { 2668 struct btrfs_fs_info *fs_info = bctl->fs_info; 2669 2670 BUG_ON(fs_info->balance_ctl); 2671 2672 spin_lock(&fs_info->balance_lock); 2673 fs_info->balance_ctl = bctl; 2674 spin_unlock(&fs_info->balance_lock); 2675 } 2676 2677 static void unset_balance_control(struct btrfs_fs_info *fs_info) 2678 { 2679 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2680 2681 BUG_ON(!fs_info->balance_ctl); 2682 2683 spin_lock(&fs_info->balance_lock); 2684 fs_info->balance_ctl = NULL; 2685 spin_unlock(&fs_info->balance_lock); 2686 2687 kfree(bctl); 2688 } 2689 2690 /* 2691 * Balance filters. Return 1 if chunk should be filtered out 2692 * (should not be balanced). 2693 */ 2694 static int chunk_profiles_filter(u64 chunk_type, 2695 struct btrfs_balance_args *bargs) 2696 { 2697 chunk_type = chunk_to_extended(chunk_type) & 2698 BTRFS_EXTENDED_PROFILE_MASK; 2699 2700 if (bargs->profiles & chunk_type) 2701 return 0; 2702 2703 return 1; 2704 } 2705 2706 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, 2707 struct btrfs_balance_args *bargs) 2708 { 2709 struct btrfs_block_group_cache *cache; 2710 u64 chunk_used, user_thresh; 2711 int ret = 1; 2712 2713 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 2714 chunk_used = btrfs_block_group_used(&cache->item); 2715 2716 if (bargs->usage == 0) 2717 user_thresh = 1; 2718 else if (bargs->usage > 100) 2719 user_thresh = cache->key.offset; 2720 else 2721 user_thresh = div_factor_fine(cache->key.offset, 2722 bargs->usage); 2723 2724 if (chunk_used < user_thresh) 2725 ret = 0; 2726 2727 btrfs_put_block_group(cache); 2728 return ret; 2729 } 2730 2731 static int chunk_devid_filter(struct extent_buffer *leaf, 2732 struct btrfs_chunk *chunk, 2733 struct btrfs_balance_args *bargs) 2734 { 2735 struct btrfs_stripe *stripe; 2736 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2737 int i; 2738 2739 for (i = 0; i < num_stripes; i++) { 2740 stripe = btrfs_stripe_nr(chunk, i); 2741 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) 2742 return 0; 2743 } 2744 2745 return 1; 2746 } 2747 2748 /* [pstart, pend) */ 2749 static int chunk_drange_filter(struct extent_buffer *leaf, 2750 struct btrfs_chunk *chunk, 2751 u64 chunk_offset, 2752 struct btrfs_balance_args *bargs) 2753 { 2754 struct btrfs_stripe *stripe; 2755 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2756 u64 stripe_offset; 2757 u64 stripe_length; 2758 int factor; 2759 int i; 2760 2761 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) 2762 return 0; 2763 2764 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP | 2765 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) { 2766 factor = num_stripes / 2; 2767 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) { 2768 factor = num_stripes - 1; 2769 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) { 2770 factor = num_stripes - 2; 2771 } else { 2772 factor = num_stripes; 2773 } 2774 2775 for (i = 0; i < num_stripes; i++) { 2776 stripe = btrfs_stripe_nr(chunk, i); 2777 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) 2778 continue; 2779 2780 stripe_offset = btrfs_stripe_offset(leaf, stripe); 2781 stripe_length = btrfs_chunk_length(leaf, chunk); 2782 do_div(stripe_length, factor); 2783 2784 if (stripe_offset < bargs->pend && 2785 stripe_offset + stripe_length > bargs->pstart) 2786 return 0; 2787 } 2788 2789 return 1; 2790 } 2791 2792 /* [vstart, vend) */ 2793 static int chunk_vrange_filter(struct extent_buffer *leaf, 2794 struct btrfs_chunk *chunk, 2795 u64 chunk_offset, 2796 struct btrfs_balance_args *bargs) 2797 { 2798 if (chunk_offset < bargs->vend && 2799 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) 2800 /* at least part of the chunk is inside this vrange */ 2801 return 0; 2802 2803 return 1; 2804 } 2805 2806 static int chunk_soft_convert_filter(u64 chunk_type, 2807 struct btrfs_balance_args *bargs) 2808 { 2809 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) 2810 return 0; 2811 2812 chunk_type = chunk_to_extended(chunk_type) & 2813 BTRFS_EXTENDED_PROFILE_MASK; 2814 2815 if (bargs->target == chunk_type) 2816 return 1; 2817 2818 return 0; 2819 } 2820 2821 static int should_balance_chunk(struct btrfs_root *root, 2822 struct extent_buffer *leaf, 2823 struct btrfs_chunk *chunk, u64 chunk_offset) 2824 { 2825 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl; 2826 struct btrfs_balance_args *bargs = NULL; 2827 u64 chunk_type = btrfs_chunk_type(leaf, chunk); 2828 2829 /* type filter */ 2830 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & 2831 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { 2832 return 0; 2833 } 2834 2835 if (chunk_type & BTRFS_BLOCK_GROUP_DATA) 2836 bargs = &bctl->data; 2837 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) 2838 bargs = &bctl->sys; 2839 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) 2840 bargs = &bctl->meta; 2841 2842 /* profiles filter */ 2843 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && 2844 chunk_profiles_filter(chunk_type, bargs)) { 2845 return 0; 2846 } 2847 2848 /* usage filter */ 2849 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && 2850 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) { 2851 return 0; 2852 } 2853 2854 /* devid filter */ 2855 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && 2856 chunk_devid_filter(leaf, chunk, bargs)) { 2857 return 0; 2858 } 2859 2860 /* drange filter, makes sense only with devid filter */ 2861 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && 2862 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) { 2863 return 0; 2864 } 2865 2866 /* vrange filter */ 2867 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && 2868 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { 2869 return 0; 2870 } 2871 2872 /* soft profile changing mode */ 2873 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && 2874 chunk_soft_convert_filter(chunk_type, bargs)) { 2875 return 0; 2876 } 2877 2878 return 1; 2879 } 2880 2881 static int __btrfs_balance(struct btrfs_fs_info *fs_info) 2882 { 2883 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2884 struct btrfs_root *chunk_root = fs_info->chunk_root; 2885 struct btrfs_root *dev_root = fs_info->dev_root; 2886 struct list_head *devices; 2887 struct btrfs_device *device; 2888 u64 old_size; 2889 u64 size_to_free; 2890 struct btrfs_chunk *chunk; 2891 struct btrfs_path *path; 2892 struct btrfs_key key; 2893 struct btrfs_key found_key; 2894 struct btrfs_trans_handle *trans; 2895 struct extent_buffer *leaf; 2896 int slot; 2897 int ret; 2898 int enospc_errors = 0; 2899 bool counting = true; 2900 2901 /* step one make some room on all the devices */ 2902 devices = &fs_info->fs_devices->devices; 2903 list_for_each_entry(device, devices, dev_list) { 2904 old_size = device->total_bytes; 2905 size_to_free = div_factor(old_size, 1); 2906 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024); 2907 if (!device->writeable || 2908 device->total_bytes - device->bytes_used > size_to_free || 2909 device->is_tgtdev_for_dev_replace) 2910 continue; 2911 2912 ret = btrfs_shrink_device(device, old_size - size_to_free); 2913 if (ret == -ENOSPC) 2914 break; 2915 BUG_ON(ret); 2916 2917 trans = btrfs_start_transaction(dev_root, 0); 2918 BUG_ON(IS_ERR(trans)); 2919 2920 ret = btrfs_grow_device(trans, device, old_size); 2921 BUG_ON(ret); 2922 2923 btrfs_end_transaction(trans, dev_root); 2924 } 2925 2926 /* step two, relocate all the chunks */ 2927 path = btrfs_alloc_path(); 2928 if (!path) { 2929 ret = -ENOMEM; 2930 goto error; 2931 } 2932 2933 /* zero out stat counters */ 2934 spin_lock(&fs_info->balance_lock); 2935 memset(&bctl->stat, 0, sizeof(bctl->stat)); 2936 spin_unlock(&fs_info->balance_lock); 2937 again: 2938 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2939 key.offset = (u64)-1; 2940 key.type = BTRFS_CHUNK_ITEM_KEY; 2941 2942 while (1) { 2943 if ((!counting && atomic_read(&fs_info->balance_pause_req)) || 2944 atomic_read(&fs_info->balance_cancel_req)) { 2945 ret = -ECANCELED; 2946 goto error; 2947 } 2948 2949 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2950 if (ret < 0) 2951 goto error; 2952 2953 /* 2954 * this shouldn't happen, it means the last relocate 2955 * failed 2956 */ 2957 if (ret == 0) 2958 BUG(); /* FIXME break ? */ 2959 2960 ret = btrfs_previous_item(chunk_root, path, 0, 2961 BTRFS_CHUNK_ITEM_KEY); 2962 if (ret) { 2963 ret = 0; 2964 break; 2965 } 2966 2967 leaf = path->nodes[0]; 2968 slot = path->slots[0]; 2969 btrfs_item_key_to_cpu(leaf, &found_key, slot); 2970 2971 if (found_key.objectid != key.objectid) 2972 break; 2973 2974 /* chunk zero is special */ 2975 if (found_key.offset == 0) 2976 break; 2977 2978 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 2979 2980 if (!counting) { 2981 spin_lock(&fs_info->balance_lock); 2982 bctl->stat.considered++; 2983 spin_unlock(&fs_info->balance_lock); 2984 } 2985 2986 ret = should_balance_chunk(chunk_root, leaf, chunk, 2987 found_key.offset); 2988 btrfs_release_path(path); 2989 if (!ret) 2990 goto loop; 2991 2992 if (counting) { 2993 spin_lock(&fs_info->balance_lock); 2994 bctl->stat.expected++; 2995 spin_unlock(&fs_info->balance_lock); 2996 goto loop; 2997 } 2998 2999 ret = btrfs_relocate_chunk(chunk_root, 3000 chunk_root->root_key.objectid, 3001 found_key.objectid, 3002 found_key.offset); 3003 if (ret && ret != -ENOSPC) 3004 goto error; 3005 if (ret == -ENOSPC) { 3006 enospc_errors++; 3007 } else { 3008 spin_lock(&fs_info->balance_lock); 3009 bctl->stat.completed++; 3010 spin_unlock(&fs_info->balance_lock); 3011 } 3012 loop: 3013 key.offset = found_key.offset - 1; 3014 } 3015 3016 if (counting) { 3017 btrfs_release_path(path); 3018 counting = false; 3019 goto again; 3020 } 3021 error: 3022 btrfs_free_path(path); 3023 if (enospc_errors) { 3024 printk(KERN_INFO "btrfs: %d enospc errors during balance\n", 3025 enospc_errors); 3026 if (!ret) 3027 ret = -ENOSPC; 3028 } 3029 3030 return ret; 3031 } 3032 3033 /** 3034 * alloc_profile_is_valid - see if a given profile is valid and reduced 3035 * @flags: profile to validate 3036 * @extended: if true @flags is treated as an extended profile 3037 */ 3038 static int alloc_profile_is_valid(u64 flags, int extended) 3039 { 3040 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK : 3041 BTRFS_BLOCK_GROUP_PROFILE_MASK); 3042 3043 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK; 3044 3045 /* 1) check that all other bits are zeroed */ 3046 if (flags & ~mask) 3047 return 0; 3048 3049 /* 2) see if profile is reduced */ 3050 if (flags == 0) 3051 return !extended; /* "0" is valid for usual profiles */ 3052 3053 /* true if exactly one bit set */ 3054 return (flags & (flags - 1)) == 0; 3055 } 3056 3057 static inline int balance_need_close(struct btrfs_fs_info *fs_info) 3058 { 3059 /* cancel requested || normal exit path */ 3060 return atomic_read(&fs_info->balance_cancel_req) || 3061 (atomic_read(&fs_info->balance_pause_req) == 0 && 3062 atomic_read(&fs_info->balance_cancel_req) == 0); 3063 } 3064 3065 static void __cancel_balance(struct btrfs_fs_info *fs_info) 3066 { 3067 int ret; 3068 3069 unset_balance_control(fs_info); 3070 ret = del_balance_item(fs_info->tree_root); 3071 if (ret) 3072 btrfs_std_error(fs_info, ret); 3073 3074 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3075 } 3076 3077 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3078 struct btrfs_ioctl_balance_args *bargs); 3079 3080 /* 3081 * Should be called with both balance and volume mutexes held 3082 */ 3083 int btrfs_balance(struct btrfs_balance_control *bctl, 3084 struct btrfs_ioctl_balance_args *bargs) 3085 { 3086 struct btrfs_fs_info *fs_info = bctl->fs_info; 3087 u64 allowed; 3088 int mixed = 0; 3089 int ret; 3090 u64 num_devices; 3091 unsigned seq; 3092 3093 if (btrfs_fs_closing(fs_info) || 3094 atomic_read(&fs_info->balance_pause_req) || 3095 atomic_read(&fs_info->balance_cancel_req)) { 3096 ret = -EINVAL; 3097 goto out; 3098 } 3099 3100 allowed = btrfs_super_incompat_flags(fs_info->super_copy); 3101 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) 3102 mixed = 1; 3103 3104 /* 3105 * In case of mixed groups both data and meta should be picked, 3106 * and identical options should be given for both of them. 3107 */ 3108 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA; 3109 if (mixed && (bctl->flags & allowed)) { 3110 if (!(bctl->flags & BTRFS_BALANCE_DATA) || 3111 !(bctl->flags & BTRFS_BALANCE_METADATA) || 3112 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { 3113 printk(KERN_ERR "btrfs: with mixed groups data and " 3114 "metadata balance options must be the same\n"); 3115 ret = -EINVAL; 3116 goto out; 3117 } 3118 } 3119 3120 num_devices = fs_info->fs_devices->num_devices; 3121 btrfs_dev_replace_lock(&fs_info->dev_replace); 3122 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { 3123 BUG_ON(num_devices < 1); 3124 num_devices--; 3125 } 3126 btrfs_dev_replace_unlock(&fs_info->dev_replace); 3127 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; 3128 if (num_devices == 1) 3129 allowed |= BTRFS_BLOCK_GROUP_DUP; 3130 else if (num_devices > 1) 3131 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1); 3132 if (num_devices > 2) 3133 allowed |= BTRFS_BLOCK_GROUP_RAID5; 3134 if (num_devices > 3) 3135 allowed |= (BTRFS_BLOCK_GROUP_RAID10 | 3136 BTRFS_BLOCK_GROUP_RAID6); 3137 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3138 (!alloc_profile_is_valid(bctl->data.target, 1) || 3139 (bctl->data.target & ~allowed))) { 3140 printk(KERN_ERR "btrfs: unable to start balance with target " 3141 "data profile %llu\n", 3142 (unsigned long long)bctl->data.target); 3143 ret = -EINVAL; 3144 goto out; 3145 } 3146 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3147 (!alloc_profile_is_valid(bctl->meta.target, 1) || 3148 (bctl->meta.target & ~allowed))) { 3149 printk(KERN_ERR "btrfs: unable to start balance with target " 3150 "metadata profile %llu\n", 3151 (unsigned long long)bctl->meta.target); 3152 ret = -EINVAL; 3153 goto out; 3154 } 3155 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3156 (!alloc_profile_is_valid(bctl->sys.target, 1) || 3157 (bctl->sys.target & ~allowed))) { 3158 printk(KERN_ERR "btrfs: unable to start balance with target " 3159 "system profile %llu\n", 3160 (unsigned long long)bctl->sys.target); 3161 ret = -EINVAL; 3162 goto out; 3163 } 3164 3165 /* allow dup'ed data chunks only in mixed mode */ 3166 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3167 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) { 3168 printk(KERN_ERR "btrfs: dup for data is not allowed\n"); 3169 ret = -EINVAL; 3170 goto out; 3171 } 3172 3173 /* allow to reduce meta or sys integrity only if force set */ 3174 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | 3175 BTRFS_BLOCK_GROUP_RAID10 | 3176 BTRFS_BLOCK_GROUP_RAID5 | 3177 BTRFS_BLOCK_GROUP_RAID6; 3178 do { 3179 seq = read_seqbegin(&fs_info->profiles_lock); 3180 3181 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3182 (fs_info->avail_system_alloc_bits & allowed) && 3183 !(bctl->sys.target & allowed)) || 3184 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3185 (fs_info->avail_metadata_alloc_bits & allowed) && 3186 !(bctl->meta.target & allowed))) { 3187 if (bctl->flags & BTRFS_BALANCE_FORCE) { 3188 printk(KERN_INFO "btrfs: force reducing metadata " 3189 "integrity\n"); 3190 } else { 3191 printk(KERN_ERR "btrfs: balance will reduce metadata " 3192 "integrity, use force if you want this\n"); 3193 ret = -EINVAL; 3194 goto out; 3195 } 3196 } 3197 } while (read_seqretry(&fs_info->profiles_lock, seq)); 3198 3199 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3200 int num_tolerated_disk_barrier_failures; 3201 u64 target = bctl->sys.target; 3202 3203 num_tolerated_disk_barrier_failures = 3204 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3205 if (num_tolerated_disk_barrier_failures > 0 && 3206 (target & 3207 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 | 3208 BTRFS_AVAIL_ALLOC_BIT_SINGLE))) 3209 num_tolerated_disk_barrier_failures = 0; 3210 else if (num_tolerated_disk_barrier_failures > 1 && 3211 (target & 3212 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10))) 3213 num_tolerated_disk_barrier_failures = 1; 3214 3215 fs_info->num_tolerated_disk_barrier_failures = 3216 num_tolerated_disk_barrier_failures; 3217 } 3218 3219 ret = insert_balance_item(fs_info->tree_root, bctl); 3220 if (ret && ret != -EEXIST) 3221 goto out; 3222 3223 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { 3224 BUG_ON(ret == -EEXIST); 3225 set_balance_control(bctl); 3226 } else { 3227 BUG_ON(ret != -EEXIST); 3228 spin_lock(&fs_info->balance_lock); 3229 update_balance_args(bctl); 3230 spin_unlock(&fs_info->balance_lock); 3231 } 3232 3233 atomic_inc(&fs_info->balance_running); 3234 mutex_unlock(&fs_info->balance_mutex); 3235 3236 ret = __btrfs_balance(fs_info); 3237 3238 mutex_lock(&fs_info->balance_mutex); 3239 atomic_dec(&fs_info->balance_running); 3240 3241 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3242 fs_info->num_tolerated_disk_barrier_failures = 3243 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3244 } 3245 3246 if (bargs) { 3247 memset(bargs, 0, sizeof(*bargs)); 3248 update_ioctl_balance_args(fs_info, 0, bargs); 3249 } 3250 3251 if ((ret && ret != -ECANCELED && ret != -ENOSPC) || 3252 balance_need_close(fs_info)) { 3253 __cancel_balance(fs_info); 3254 } 3255 3256 wake_up(&fs_info->balance_wait_q); 3257 3258 return ret; 3259 out: 3260 if (bctl->flags & BTRFS_BALANCE_RESUME) 3261 __cancel_balance(fs_info); 3262 else { 3263 kfree(bctl); 3264 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3265 } 3266 return ret; 3267 } 3268 3269 static int balance_kthread(void *data) 3270 { 3271 struct btrfs_fs_info *fs_info = data; 3272 int ret = 0; 3273 3274 mutex_lock(&fs_info->volume_mutex); 3275 mutex_lock(&fs_info->balance_mutex); 3276 3277 if (fs_info->balance_ctl) { 3278 printk(KERN_INFO "btrfs: continuing balance\n"); 3279 ret = btrfs_balance(fs_info->balance_ctl, NULL); 3280 } 3281 3282 mutex_unlock(&fs_info->balance_mutex); 3283 mutex_unlock(&fs_info->volume_mutex); 3284 3285 return ret; 3286 } 3287 3288 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info) 3289 { 3290 struct task_struct *tsk; 3291 3292 spin_lock(&fs_info->balance_lock); 3293 if (!fs_info->balance_ctl) { 3294 spin_unlock(&fs_info->balance_lock); 3295 return 0; 3296 } 3297 spin_unlock(&fs_info->balance_lock); 3298 3299 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) { 3300 printk(KERN_INFO "btrfs: force skipping balance\n"); 3301 return 0; 3302 } 3303 3304 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance"); 3305 return PTR_RET(tsk); 3306 } 3307 3308 int btrfs_recover_balance(struct btrfs_fs_info *fs_info) 3309 { 3310 struct btrfs_balance_control *bctl; 3311 struct btrfs_balance_item *item; 3312 struct btrfs_disk_balance_args disk_bargs; 3313 struct btrfs_path *path; 3314 struct extent_buffer *leaf; 3315 struct btrfs_key key; 3316 int ret; 3317 3318 path = btrfs_alloc_path(); 3319 if (!path) 3320 return -ENOMEM; 3321 3322 key.objectid = BTRFS_BALANCE_OBJECTID; 3323 key.type = BTRFS_BALANCE_ITEM_KEY; 3324 key.offset = 0; 3325 3326 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 3327 if (ret < 0) 3328 goto out; 3329 if (ret > 0) { /* ret = -ENOENT; */ 3330 ret = 0; 3331 goto out; 3332 } 3333 3334 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3335 if (!bctl) { 3336 ret = -ENOMEM; 3337 goto out; 3338 } 3339 3340 leaf = path->nodes[0]; 3341 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 3342 3343 bctl->fs_info = fs_info; 3344 bctl->flags = btrfs_balance_flags(leaf, item); 3345 bctl->flags |= BTRFS_BALANCE_RESUME; 3346 3347 btrfs_balance_data(leaf, item, &disk_bargs); 3348 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); 3349 btrfs_balance_meta(leaf, item, &disk_bargs); 3350 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); 3351 btrfs_balance_sys(leaf, item, &disk_bargs); 3352 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); 3353 3354 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)); 3355 3356 mutex_lock(&fs_info->volume_mutex); 3357 mutex_lock(&fs_info->balance_mutex); 3358 3359 set_balance_control(bctl); 3360 3361 mutex_unlock(&fs_info->balance_mutex); 3362 mutex_unlock(&fs_info->volume_mutex); 3363 out: 3364 btrfs_free_path(path); 3365 return ret; 3366 } 3367 3368 int btrfs_pause_balance(struct btrfs_fs_info *fs_info) 3369 { 3370 int ret = 0; 3371 3372 mutex_lock(&fs_info->balance_mutex); 3373 if (!fs_info->balance_ctl) { 3374 mutex_unlock(&fs_info->balance_mutex); 3375 return -ENOTCONN; 3376 } 3377 3378 if (atomic_read(&fs_info->balance_running)) { 3379 atomic_inc(&fs_info->balance_pause_req); 3380 mutex_unlock(&fs_info->balance_mutex); 3381 3382 wait_event(fs_info->balance_wait_q, 3383 atomic_read(&fs_info->balance_running) == 0); 3384 3385 mutex_lock(&fs_info->balance_mutex); 3386 /* we are good with balance_ctl ripped off from under us */ 3387 BUG_ON(atomic_read(&fs_info->balance_running)); 3388 atomic_dec(&fs_info->balance_pause_req); 3389 } else { 3390 ret = -ENOTCONN; 3391 } 3392 3393 mutex_unlock(&fs_info->balance_mutex); 3394 return ret; 3395 } 3396 3397 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) 3398 { 3399 mutex_lock(&fs_info->balance_mutex); 3400 if (!fs_info->balance_ctl) { 3401 mutex_unlock(&fs_info->balance_mutex); 3402 return -ENOTCONN; 3403 } 3404 3405 atomic_inc(&fs_info->balance_cancel_req); 3406 /* 3407 * if we are running just wait and return, balance item is 3408 * deleted in btrfs_balance in this case 3409 */ 3410 if (atomic_read(&fs_info->balance_running)) { 3411 mutex_unlock(&fs_info->balance_mutex); 3412 wait_event(fs_info->balance_wait_q, 3413 atomic_read(&fs_info->balance_running) == 0); 3414 mutex_lock(&fs_info->balance_mutex); 3415 } else { 3416 /* __cancel_balance needs volume_mutex */ 3417 mutex_unlock(&fs_info->balance_mutex); 3418 mutex_lock(&fs_info->volume_mutex); 3419 mutex_lock(&fs_info->balance_mutex); 3420 3421 if (fs_info->balance_ctl) 3422 __cancel_balance(fs_info); 3423 3424 mutex_unlock(&fs_info->volume_mutex); 3425 } 3426 3427 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running)); 3428 atomic_dec(&fs_info->balance_cancel_req); 3429 mutex_unlock(&fs_info->balance_mutex); 3430 return 0; 3431 } 3432 3433 /* 3434 * shrinking a device means finding all of the device extents past 3435 * the new size, and then following the back refs to the chunks. 3436 * The chunk relocation code actually frees the device extent 3437 */ 3438 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 3439 { 3440 struct btrfs_trans_handle *trans; 3441 struct btrfs_root *root = device->dev_root; 3442 struct btrfs_dev_extent *dev_extent = NULL; 3443 struct btrfs_path *path; 3444 u64 length; 3445 u64 chunk_tree; 3446 u64 chunk_objectid; 3447 u64 chunk_offset; 3448 int ret; 3449 int slot; 3450 int failed = 0; 3451 bool retried = false; 3452 struct extent_buffer *l; 3453 struct btrfs_key key; 3454 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3455 u64 old_total = btrfs_super_total_bytes(super_copy); 3456 u64 old_size = device->total_bytes; 3457 u64 diff = device->total_bytes - new_size; 3458 3459 if (device->is_tgtdev_for_dev_replace) 3460 return -EINVAL; 3461 3462 path = btrfs_alloc_path(); 3463 if (!path) 3464 return -ENOMEM; 3465 3466 path->reada = 2; 3467 3468 lock_chunks(root); 3469 3470 device->total_bytes = new_size; 3471 if (device->writeable) { 3472 device->fs_devices->total_rw_bytes -= diff; 3473 spin_lock(&root->fs_info->free_chunk_lock); 3474 root->fs_info->free_chunk_space -= diff; 3475 spin_unlock(&root->fs_info->free_chunk_lock); 3476 } 3477 unlock_chunks(root); 3478 3479 again: 3480 key.objectid = device->devid; 3481 key.offset = (u64)-1; 3482 key.type = BTRFS_DEV_EXTENT_KEY; 3483 3484 do { 3485 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3486 if (ret < 0) 3487 goto done; 3488 3489 ret = btrfs_previous_item(root, path, 0, key.type); 3490 if (ret < 0) 3491 goto done; 3492 if (ret) { 3493 ret = 0; 3494 btrfs_release_path(path); 3495 break; 3496 } 3497 3498 l = path->nodes[0]; 3499 slot = path->slots[0]; 3500 btrfs_item_key_to_cpu(l, &key, path->slots[0]); 3501 3502 if (key.objectid != device->devid) { 3503 btrfs_release_path(path); 3504 break; 3505 } 3506 3507 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 3508 length = btrfs_dev_extent_length(l, dev_extent); 3509 3510 if (key.offset + length <= new_size) { 3511 btrfs_release_path(path); 3512 break; 3513 } 3514 3515 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); 3516 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); 3517 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); 3518 btrfs_release_path(path); 3519 3520 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, 3521 chunk_offset); 3522 if (ret && ret != -ENOSPC) 3523 goto done; 3524 if (ret == -ENOSPC) 3525 failed++; 3526 } while (key.offset-- > 0); 3527 3528 if (failed && !retried) { 3529 failed = 0; 3530 retried = true; 3531 goto again; 3532 } else if (failed && retried) { 3533 ret = -ENOSPC; 3534 lock_chunks(root); 3535 3536 device->total_bytes = old_size; 3537 if (device->writeable) 3538 device->fs_devices->total_rw_bytes += diff; 3539 spin_lock(&root->fs_info->free_chunk_lock); 3540 root->fs_info->free_chunk_space += diff; 3541 spin_unlock(&root->fs_info->free_chunk_lock); 3542 unlock_chunks(root); 3543 goto done; 3544 } 3545 3546 /* Shrinking succeeded, else we would be at "done". */ 3547 trans = btrfs_start_transaction(root, 0); 3548 if (IS_ERR(trans)) { 3549 ret = PTR_ERR(trans); 3550 goto done; 3551 } 3552 3553 lock_chunks(root); 3554 3555 device->disk_total_bytes = new_size; 3556 /* Now btrfs_update_device() will change the on-disk size. */ 3557 ret = btrfs_update_device(trans, device); 3558 if (ret) { 3559 unlock_chunks(root); 3560 btrfs_end_transaction(trans, root); 3561 goto done; 3562 } 3563 WARN_ON(diff > old_total); 3564 btrfs_set_super_total_bytes(super_copy, old_total - diff); 3565 unlock_chunks(root); 3566 btrfs_end_transaction(trans, root); 3567 done: 3568 btrfs_free_path(path); 3569 return ret; 3570 } 3571 3572 static int btrfs_add_system_chunk(struct btrfs_root *root, 3573 struct btrfs_key *key, 3574 struct btrfs_chunk *chunk, int item_size) 3575 { 3576 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3577 struct btrfs_disk_key disk_key; 3578 u32 array_size; 3579 u8 *ptr; 3580 3581 array_size = btrfs_super_sys_array_size(super_copy); 3582 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) 3583 return -EFBIG; 3584 3585 ptr = super_copy->sys_chunk_array + array_size; 3586 btrfs_cpu_key_to_disk(&disk_key, key); 3587 memcpy(ptr, &disk_key, sizeof(disk_key)); 3588 ptr += sizeof(disk_key); 3589 memcpy(ptr, chunk, item_size); 3590 item_size += sizeof(disk_key); 3591 btrfs_set_super_sys_array_size(super_copy, array_size + item_size); 3592 return 0; 3593 } 3594 3595 /* 3596 * sort the devices in descending order by max_avail, total_avail 3597 */ 3598 static int btrfs_cmp_device_info(const void *a, const void *b) 3599 { 3600 const struct btrfs_device_info *di_a = a; 3601 const struct btrfs_device_info *di_b = b; 3602 3603 if (di_a->max_avail > di_b->max_avail) 3604 return -1; 3605 if (di_a->max_avail < di_b->max_avail) 3606 return 1; 3607 if (di_a->total_avail > di_b->total_avail) 3608 return -1; 3609 if (di_a->total_avail < di_b->total_avail) 3610 return 1; 3611 return 0; 3612 } 3613 3614 static struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { 3615 [BTRFS_RAID_RAID10] = { 3616 .sub_stripes = 2, 3617 .dev_stripes = 1, 3618 .devs_max = 0, /* 0 == as many as possible */ 3619 .devs_min = 4, 3620 .devs_increment = 2, 3621 .ncopies = 2, 3622 }, 3623 [BTRFS_RAID_RAID1] = { 3624 .sub_stripes = 1, 3625 .dev_stripes = 1, 3626 .devs_max = 2, 3627 .devs_min = 2, 3628 .devs_increment = 2, 3629 .ncopies = 2, 3630 }, 3631 [BTRFS_RAID_DUP] = { 3632 .sub_stripes = 1, 3633 .dev_stripes = 2, 3634 .devs_max = 1, 3635 .devs_min = 1, 3636 .devs_increment = 1, 3637 .ncopies = 2, 3638 }, 3639 [BTRFS_RAID_RAID0] = { 3640 .sub_stripes = 1, 3641 .dev_stripes = 1, 3642 .devs_max = 0, 3643 .devs_min = 2, 3644 .devs_increment = 1, 3645 .ncopies = 1, 3646 }, 3647 [BTRFS_RAID_SINGLE] = { 3648 .sub_stripes = 1, 3649 .dev_stripes = 1, 3650 .devs_max = 1, 3651 .devs_min = 1, 3652 .devs_increment = 1, 3653 .ncopies = 1, 3654 }, 3655 [BTRFS_RAID_RAID5] = { 3656 .sub_stripes = 1, 3657 .dev_stripes = 1, 3658 .devs_max = 0, 3659 .devs_min = 2, 3660 .devs_increment = 1, 3661 .ncopies = 2, 3662 }, 3663 [BTRFS_RAID_RAID6] = { 3664 .sub_stripes = 1, 3665 .dev_stripes = 1, 3666 .devs_max = 0, 3667 .devs_min = 3, 3668 .devs_increment = 1, 3669 .ncopies = 3, 3670 }, 3671 }; 3672 3673 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target) 3674 { 3675 /* TODO allow them to set a preferred stripe size */ 3676 return 64 * 1024; 3677 } 3678 3679 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type) 3680 { 3681 if (!(type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))) 3682 return; 3683 3684 btrfs_set_fs_incompat(info, RAID56); 3685 } 3686 3687 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 3688 struct btrfs_root *extent_root, u64 start, 3689 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(trans, 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 num_bytes = stripe_size * data_stripes; 3909 3910 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes); 3911 3912 em = alloc_extent_map(); 3913 if (!em) { 3914 ret = -ENOMEM; 3915 goto error; 3916 } 3917 em->bdev = (struct block_device *)map; 3918 em->start = start; 3919 em->len = num_bytes; 3920 em->block_start = 0; 3921 em->block_len = em->len; 3922 em->orig_block_len = stripe_size; 3923 3924 em_tree = &extent_root->fs_info->mapping_tree.map_tree; 3925 write_lock(&em_tree->lock); 3926 ret = add_extent_mapping(em_tree, em, 0); 3927 if (!ret) { 3928 list_add_tail(&em->list, &trans->transaction->pending_chunks); 3929 atomic_inc(&em->refs); 3930 } 3931 write_unlock(&em_tree->lock); 3932 if (ret) { 3933 free_extent_map(em); 3934 goto error; 3935 } 3936 3937 ret = btrfs_make_block_group(trans, extent_root, 0, type, 3938 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3939 start, num_bytes); 3940 if (ret) 3941 goto error_del_extent; 3942 3943 free_extent_map(em); 3944 check_raid56_incompat_flag(extent_root->fs_info, type); 3945 3946 kfree(devices_info); 3947 return 0; 3948 3949 error_del_extent: 3950 write_lock(&em_tree->lock); 3951 remove_extent_mapping(em_tree, em); 3952 write_unlock(&em_tree->lock); 3953 3954 /* One for our allocation */ 3955 free_extent_map(em); 3956 /* One for the tree reference */ 3957 free_extent_map(em); 3958 error: 3959 kfree(map); 3960 kfree(devices_info); 3961 return ret; 3962 } 3963 3964 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans, 3965 struct btrfs_root *extent_root, 3966 u64 chunk_offset, u64 chunk_size) 3967 { 3968 struct btrfs_key key; 3969 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 3970 struct btrfs_device *device; 3971 struct btrfs_chunk *chunk; 3972 struct btrfs_stripe *stripe; 3973 struct extent_map_tree *em_tree; 3974 struct extent_map *em; 3975 struct map_lookup *map; 3976 size_t item_size; 3977 u64 dev_offset; 3978 u64 stripe_size; 3979 int i = 0; 3980 int ret; 3981 3982 em_tree = &extent_root->fs_info->mapping_tree.map_tree; 3983 read_lock(&em_tree->lock); 3984 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size); 3985 read_unlock(&em_tree->lock); 3986 3987 if (!em) { 3988 btrfs_crit(extent_root->fs_info, "unable to find logical " 3989 "%Lu len %Lu", chunk_offset, chunk_size); 3990 return -EINVAL; 3991 } 3992 3993 if (em->start != chunk_offset || em->len != chunk_size) { 3994 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted" 3995 " %Lu-%Lu, found %Lu-%Lu\n", chunk_offset, 3996 chunk_size, em->start, em->len); 3997 free_extent_map(em); 3998 return -EINVAL; 3999 } 4000 4001 map = (struct map_lookup *)em->bdev; 4002 item_size = btrfs_chunk_item_size(map->num_stripes); 4003 stripe_size = em->orig_block_len; 4004 4005 chunk = kzalloc(item_size, GFP_NOFS); 4006 if (!chunk) { 4007 ret = -ENOMEM; 4008 goto out; 4009 } 4010 4011 for (i = 0; i < map->num_stripes; i++) { 4012 device = map->stripes[i].dev; 4013 dev_offset = map->stripes[i].physical; 4014 4015 device->bytes_used += stripe_size; 4016 ret = btrfs_update_device(trans, device); 4017 if (ret) 4018 goto out; 4019 ret = btrfs_alloc_dev_extent(trans, device, 4020 chunk_root->root_key.objectid, 4021 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 4022 chunk_offset, dev_offset, 4023 stripe_size); 4024 if (ret) 4025 goto out; 4026 } 4027 4028 spin_lock(&extent_root->fs_info->free_chunk_lock); 4029 extent_root->fs_info->free_chunk_space -= (stripe_size * 4030 map->num_stripes); 4031 spin_unlock(&extent_root->fs_info->free_chunk_lock); 4032 4033 stripe = &chunk->stripe; 4034 for (i = 0; i < map->num_stripes; i++) { 4035 device = map->stripes[i].dev; 4036 dev_offset = map->stripes[i].physical; 4037 4038 btrfs_set_stack_stripe_devid(stripe, device->devid); 4039 btrfs_set_stack_stripe_offset(stripe, dev_offset); 4040 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); 4041 stripe++; 4042 } 4043 4044 btrfs_set_stack_chunk_length(chunk, chunk_size); 4045 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); 4046 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); 4047 btrfs_set_stack_chunk_type(chunk, map->type); 4048 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); 4049 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); 4050 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); 4051 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); 4052 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); 4053 4054 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 4055 key.type = BTRFS_CHUNK_ITEM_KEY; 4056 key.offset = chunk_offset; 4057 4058 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); 4059 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 4060 /* 4061 * TODO: Cleanup of inserted chunk root in case of 4062 * failure. 4063 */ 4064 ret = btrfs_add_system_chunk(chunk_root, &key, chunk, 4065 item_size); 4066 } 4067 4068 out: 4069 kfree(chunk); 4070 free_extent_map(em); 4071 return ret; 4072 } 4073 4074 /* 4075 * Chunk allocation falls into two parts. The first part does works 4076 * that make the new allocated chunk useable, but not do any operation 4077 * that modifies the chunk tree. The second part does the works that 4078 * require modifying the chunk tree. This division is important for the 4079 * bootstrap process of adding storage to a seed btrfs. 4080 */ 4081 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 4082 struct btrfs_root *extent_root, u64 type) 4083 { 4084 u64 chunk_offset; 4085 4086 chunk_offset = find_next_chunk(extent_root->fs_info); 4087 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type); 4088 } 4089 4090 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans, 4091 struct btrfs_root *root, 4092 struct btrfs_device *device) 4093 { 4094 u64 chunk_offset; 4095 u64 sys_chunk_offset; 4096 u64 alloc_profile; 4097 struct btrfs_fs_info *fs_info = root->fs_info; 4098 struct btrfs_root *extent_root = fs_info->extent_root; 4099 int ret; 4100 4101 chunk_offset = find_next_chunk(fs_info); 4102 alloc_profile = btrfs_get_alloc_profile(extent_root, 0); 4103 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset, 4104 alloc_profile); 4105 if (ret) 4106 return ret; 4107 4108 sys_chunk_offset = find_next_chunk(root->fs_info); 4109 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0); 4110 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset, 4111 alloc_profile); 4112 if (ret) { 4113 btrfs_abort_transaction(trans, root, ret); 4114 goto out; 4115 } 4116 4117 ret = btrfs_add_device(trans, fs_info->chunk_root, device); 4118 if (ret) 4119 btrfs_abort_transaction(trans, root, ret); 4120 out: 4121 return ret; 4122 } 4123 4124 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) 4125 { 4126 struct extent_map *em; 4127 struct map_lookup *map; 4128 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 4129 int readonly = 0; 4130 int i; 4131 4132 read_lock(&map_tree->map_tree.lock); 4133 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); 4134 read_unlock(&map_tree->map_tree.lock); 4135 if (!em) 4136 return 1; 4137 4138 if (btrfs_test_opt(root, DEGRADED)) { 4139 free_extent_map(em); 4140 return 0; 4141 } 4142 4143 map = (struct map_lookup *)em->bdev; 4144 for (i = 0; i < map->num_stripes; i++) { 4145 if (!map->stripes[i].dev->writeable) { 4146 readonly = 1; 4147 break; 4148 } 4149 } 4150 free_extent_map(em); 4151 return readonly; 4152 } 4153 4154 void btrfs_mapping_init(struct btrfs_mapping_tree *tree) 4155 { 4156 extent_map_tree_init(&tree->map_tree); 4157 } 4158 4159 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree) 4160 { 4161 struct extent_map *em; 4162 4163 while (1) { 4164 write_lock(&tree->map_tree.lock); 4165 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1); 4166 if (em) 4167 remove_extent_mapping(&tree->map_tree, em); 4168 write_unlock(&tree->map_tree.lock); 4169 if (!em) 4170 break; 4171 kfree(em->bdev); 4172 /* once for us */ 4173 free_extent_map(em); 4174 /* once for the tree */ 4175 free_extent_map(em); 4176 } 4177 } 4178 4179 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) 4180 { 4181 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4182 struct extent_map *em; 4183 struct map_lookup *map; 4184 struct extent_map_tree *em_tree = &map_tree->map_tree; 4185 int ret; 4186 4187 read_lock(&em_tree->lock); 4188 em = lookup_extent_mapping(em_tree, logical, len); 4189 read_unlock(&em_tree->lock); 4190 4191 /* 4192 * We could return errors for these cases, but that could get ugly and 4193 * we'd probably do the same thing which is just not do anything else 4194 * and exit, so return 1 so the callers don't try to use other copies. 4195 */ 4196 if (!em) { 4197 btrfs_emerg(fs_info, "No mapping for %Lu-%Lu\n", logical, 4198 logical+len); 4199 return 1; 4200 } 4201 4202 if (em->start > logical || em->start + em->len < logical) { 4203 btrfs_emerg(fs_info, "Invalid mapping for %Lu-%Lu, got " 4204 "%Lu-%Lu\n", logical, logical+len, em->start, 4205 em->start + em->len); 4206 return 1; 4207 } 4208 4209 map = (struct map_lookup *)em->bdev; 4210 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1)) 4211 ret = map->num_stripes; 4212 else if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4213 ret = map->sub_stripes; 4214 else if (map->type & BTRFS_BLOCK_GROUP_RAID5) 4215 ret = 2; 4216 else if (map->type & BTRFS_BLOCK_GROUP_RAID6) 4217 ret = 3; 4218 else 4219 ret = 1; 4220 free_extent_map(em); 4221 4222 btrfs_dev_replace_lock(&fs_info->dev_replace); 4223 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) 4224 ret++; 4225 btrfs_dev_replace_unlock(&fs_info->dev_replace); 4226 4227 return ret; 4228 } 4229 4230 unsigned long btrfs_full_stripe_len(struct btrfs_root *root, 4231 struct btrfs_mapping_tree *map_tree, 4232 u64 logical) 4233 { 4234 struct extent_map *em; 4235 struct map_lookup *map; 4236 struct extent_map_tree *em_tree = &map_tree->map_tree; 4237 unsigned long len = root->sectorsize; 4238 4239 read_lock(&em_tree->lock); 4240 em = lookup_extent_mapping(em_tree, logical, len); 4241 read_unlock(&em_tree->lock); 4242 BUG_ON(!em); 4243 4244 BUG_ON(em->start > logical || em->start + em->len < logical); 4245 map = (struct map_lookup *)em->bdev; 4246 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4247 BTRFS_BLOCK_GROUP_RAID6)) { 4248 len = map->stripe_len * nr_data_stripes(map); 4249 } 4250 free_extent_map(em); 4251 return len; 4252 } 4253 4254 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree, 4255 u64 logical, u64 len, int mirror_num) 4256 { 4257 struct extent_map *em; 4258 struct map_lookup *map; 4259 struct extent_map_tree *em_tree = &map_tree->map_tree; 4260 int ret = 0; 4261 4262 read_lock(&em_tree->lock); 4263 em = lookup_extent_mapping(em_tree, logical, len); 4264 read_unlock(&em_tree->lock); 4265 BUG_ON(!em); 4266 4267 BUG_ON(em->start > logical || em->start + em->len < logical); 4268 map = (struct map_lookup *)em->bdev; 4269 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4270 BTRFS_BLOCK_GROUP_RAID6)) 4271 ret = 1; 4272 free_extent_map(em); 4273 return ret; 4274 } 4275 4276 static int find_live_mirror(struct btrfs_fs_info *fs_info, 4277 struct map_lookup *map, int first, int num, 4278 int optimal, int dev_replace_is_ongoing) 4279 { 4280 int i; 4281 int tolerance; 4282 struct btrfs_device *srcdev; 4283 4284 if (dev_replace_is_ongoing && 4285 fs_info->dev_replace.cont_reading_from_srcdev_mode == 4286 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID) 4287 srcdev = fs_info->dev_replace.srcdev; 4288 else 4289 srcdev = NULL; 4290 4291 /* 4292 * try to avoid the drive that is the source drive for a 4293 * dev-replace procedure, only choose it if no other non-missing 4294 * mirror is available 4295 */ 4296 for (tolerance = 0; tolerance < 2; tolerance++) { 4297 if (map->stripes[optimal].dev->bdev && 4298 (tolerance || map->stripes[optimal].dev != srcdev)) 4299 return optimal; 4300 for (i = first; i < first + num; i++) { 4301 if (map->stripes[i].dev->bdev && 4302 (tolerance || map->stripes[i].dev != srcdev)) 4303 return i; 4304 } 4305 } 4306 4307 /* we couldn't find one that doesn't fail. Just return something 4308 * and the io error handling code will clean up eventually 4309 */ 4310 return optimal; 4311 } 4312 4313 static inline int parity_smaller(u64 a, u64 b) 4314 { 4315 return a > b; 4316 } 4317 4318 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */ 4319 static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map) 4320 { 4321 struct btrfs_bio_stripe s; 4322 int i; 4323 u64 l; 4324 int again = 1; 4325 4326 while (again) { 4327 again = 0; 4328 for (i = 0; i < bbio->num_stripes - 1; i++) { 4329 if (parity_smaller(raid_map[i], raid_map[i+1])) { 4330 s = bbio->stripes[i]; 4331 l = raid_map[i]; 4332 bbio->stripes[i] = bbio->stripes[i+1]; 4333 raid_map[i] = raid_map[i+1]; 4334 bbio->stripes[i+1] = s; 4335 raid_map[i+1] = l; 4336 again = 1; 4337 } 4338 } 4339 } 4340 } 4341 4342 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4343 u64 logical, u64 *length, 4344 struct btrfs_bio **bbio_ret, 4345 int mirror_num, u64 **raid_map_ret) 4346 { 4347 struct extent_map *em; 4348 struct map_lookup *map; 4349 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4350 struct extent_map_tree *em_tree = &map_tree->map_tree; 4351 u64 offset; 4352 u64 stripe_offset; 4353 u64 stripe_end_offset; 4354 u64 stripe_nr; 4355 u64 stripe_nr_orig; 4356 u64 stripe_nr_end; 4357 u64 stripe_len; 4358 u64 *raid_map = NULL; 4359 int stripe_index; 4360 int i; 4361 int ret = 0; 4362 int num_stripes; 4363 int max_errors = 0; 4364 struct btrfs_bio *bbio = NULL; 4365 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 4366 int dev_replace_is_ongoing = 0; 4367 int num_alloc_stripes; 4368 int patch_the_first_stripe_for_dev_replace = 0; 4369 u64 physical_to_patch_in_first_stripe = 0; 4370 u64 raid56_full_stripe_start = (u64)-1; 4371 4372 read_lock(&em_tree->lock); 4373 em = lookup_extent_mapping(em_tree, logical, *length); 4374 read_unlock(&em_tree->lock); 4375 4376 if (!em) { 4377 btrfs_crit(fs_info, "unable to find logical %llu len %llu", 4378 (unsigned long long)logical, 4379 (unsigned long long)*length); 4380 return -EINVAL; 4381 } 4382 4383 if (em->start > logical || em->start + em->len < logical) { 4384 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, " 4385 "found %Lu-%Lu\n", logical, em->start, 4386 em->start + em->len); 4387 return -EINVAL; 4388 } 4389 4390 map = (struct map_lookup *)em->bdev; 4391 offset = logical - em->start; 4392 4393 stripe_len = map->stripe_len; 4394 stripe_nr = offset; 4395 /* 4396 * stripe_nr counts the total number of stripes we have to stride 4397 * to get to this block 4398 */ 4399 do_div(stripe_nr, stripe_len); 4400 4401 stripe_offset = stripe_nr * stripe_len; 4402 BUG_ON(offset < stripe_offset); 4403 4404 /* stripe_offset is the offset of this block in its stripe*/ 4405 stripe_offset = offset - stripe_offset; 4406 4407 /* if we're here for raid56, we need to know the stripe aligned start */ 4408 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { 4409 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map); 4410 raid56_full_stripe_start = offset; 4411 4412 /* allow a write of a full stripe, but make sure we don't 4413 * allow straddling of stripes 4414 */ 4415 do_div(raid56_full_stripe_start, full_stripe_len); 4416 raid56_full_stripe_start *= full_stripe_len; 4417 } 4418 4419 if (rw & REQ_DISCARD) { 4420 /* we don't discard raid56 yet */ 4421 if (map->type & 4422 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { 4423 ret = -EOPNOTSUPP; 4424 goto out; 4425 } 4426 *length = min_t(u64, em->len - offset, *length); 4427 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { 4428 u64 max_len; 4429 /* For writes to RAID[56], allow a full stripeset across all disks. 4430 For other RAID types and for RAID[56] reads, just allow a single 4431 stripe (on a single disk). */ 4432 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6) && 4433 (rw & REQ_WRITE)) { 4434 max_len = stripe_len * nr_data_stripes(map) - 4435 (offset - raid56_full_stripe_start); 4436 } else { 4437 /* we limit the length of each bio to what fits in a stripe */ 4438 max_len = stripe_len - stripe_offset; 4439 } 4440 *length = min_t(u64, em->len - offset, max_len); 4441 } else { 4442 *length = em->len - offset; 4443 } 4444 4445 /* This is for when we're called from btrfs_merge_bio_hook() and all 4446 it cares about is the length */ 4447 if (!bbio_ret) 4448 goto out; 4449 4450 btrfs_dev_replace_lock(dev_replace); 4451 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace); 4452 if (!dev_replace_is_ongoing) 4453 btrfs_dev_replace_unlock(dev_replace); 4454 4455 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 && 4456 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) && 4457 dev_replace->tgtdev != NULL) { 4458 /* 4459 * in dev-replace case, for repair case (that's the only 4460 * case where the mirror is selected explicitly when 4461 * calling btrfs_map_block), blocks left of the left cursor 4462 * can also be read from the target drive. 4463 * For REQ_GET_READ_MIRRORS, the target drive is added as 4464 * the last one to the array of stripes. For READ, it also 4465 * needs to be supported using the same mirror number. 4466 * If the requested block is not left of the left cursor, 4467 * EIO is returned. This can happen because btrfs_num_copies() 4468 * returns one more in the dev-replace case. 4469 */ 4470 u64 tmp_length = *length; 4471 struct btrfs_bio *tmp_bbio = NULL; 4472 int tmp_num_stripes; 4473 u64 srcdev_devid = dev_replace->srcdev->devid; 4474 int index_srcdev = 0; 4475 int found = 0; 4476 u64 physical_of_found = 0; 4477 4478 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, 4479 logical, &tmp_length, &tmp_bbio, 0, NULL); 4480 if (ret) { 4481 WARN_ON(tmp_bbio != NULL); 4482 goto out; 4483 } 4484 4485 tmp_num_stripes = tmp_bbio->num_stripes; 4486 if (mirror_num > tmp_num_stripes) { 4487 /* 4488 * REQ_GET_READ_MIRRORS does not contain this 4489 * mirror, that means that the requested area 4490 * is not left of the left cursor 4491 */ 4492 ret = -EIO; 4493 kfree(tmp_bbio); 4494 goto out; 4495 } 4496 4497 /* 4498 * process the rest of the function using the mirror_num 4499 * of the source drive. Therefore look it up first. 4500 * At the end, patch the device pointer to the one of the 4501 * target drive. 4502 */ 4503 for (i = 0; i < tmp_num_stripes; i++) { 4504 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) { 4505 /* 4506 * In case of DUP, in order to keep it 4507 * simple, only add the mirror with the 4508 * lowest physical address 4509 */ 4510 if (found && 4511 physical_of_found <= 4512 tmp_bbio->stripes[i].physical) 4513 continue; 4514 index_srcdev = i; 4515 found = 1; 4516 physical_of_found = 4517 tmp_bbio->stripes[i].physical; 4518 } 4519 } 4520 4521 if (found) { 4522 mirror_num = index_srcdev + 1; 4523 patch_the_first_stripe_for_dev_replace = 1; 4524 physical_to_patch_in_first_stripe = physical_of_found; 4525 } else { 4526 WARN_ON(1); 4527 ret = -EIO; 4528 kfree(tmp_bbio); 4529 goto out; 4530 } 4531 4532 kfree(tmp_bbio); 4533 } else if (mirror_num > map->num_stripes) { 4534 mirror_num = 0; 4535 } 4536 4537 num_stripes = 1; 4538 stripe_index = 0; 4539 stripe_nr_orig = stripe_nr; 4540 stripe_nr_end = ALIGN(offset + *length, map->stripe_len); 4541 do_div(stripe_nr_end, map->stripe_len); 4542 stripe_end_offset = stripe_nr_end * map->stripe_len - 4543 (offset + *length); 4544 4545 if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4546 if (rw & REQ_DISCARD) 4547 num_stripes = min_t(u64, map->num_stripes, 4548 stripe_nr_end - stripe_nr_orig); 4549 stripe_index = do_div(stripe_nr, map->num_stripes); 4550 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { 4551 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) 4552 num_stripes = map->num_stripes; 4553 else if (mirror_num) 4554 stripe_index = mirror_num - 1; 4555 else { 4556 stripe_index = find_live_mirror(fs_info, map, 0, 4557 map->num_stripes, 4558 current->pid % map->num_stripes, 4559 dev_replace_is_ongoing); 4560 mirror_num = stripe_index + 1; 4561 } 4562 4563 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { 4564 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) { 4565 num_stripes = map->num_stripes; 4566 } else if (mirror_num) { 4567 stripe_index = mirror_num - 1; 4568 } else { 4569 mirror_num = 1; 4570 } 4571 4572 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4573 int factor = map->num_stripes / map->sub_stripes; 4574 4575 stripe_index = do_div(stripe_nr, factor); 4576 stripe_index *= map->sub_stripes; 4577 4578 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) 4579 num_stripes = map->sub_stripes; 4580 else if (rw & REQ_DISCARD) 4581 num_stripes = min_t(u64, map->sub_stripes * 4582 (stripe_nr_end - stripe_nr_orig), 4583 map->num_stripes); 4584 else if (mirror_num) 4585 stripe_index += mirror_num - 1; 4586 else { 4587 int old_stripe_index = stripe_index; 4588 stripe_index = find_live_mirror(fs_info, map, 4589 stripe_index, 4590 map->sub_stripes, stripe_index + 4591 current->pid % map->sub_stripes, 4592 dev_replace_is_ongoing); 4593 mirror_num = stripe_index - old_stripe_index + 1; 4594 } 4595 4596 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4597 BTRFS_BLOCK_GROUP_RAID6)) { 4598 u64 tmp; 4599 4600 if (bbio_ret && ((rw & REQ_WRITE) || mirror_num > 1) 4601 && raid_map_ret) { 4602 int i, rot; 4603 4604 /* push stripe_nr back to the start of the full stripe */ 4605 stripe_nr = raid56_full_stripe_start; 4606 do_div(stripe_nr, stripe_len); 4607 4608 stripe_index = do_div(stripe_nr, nr_data_stripes(map)); 4609 4610 /* RAID[56] write or recovery. Return all stripes */ 4611 num_stripes = map->num_stripes; 4612 max_errors = nr_parity_stripes(map); 4613 4614 raid_map = kmalloc(sizeof(u64) * num_stripes, 4615 GFP_NOFS); 4616 if (!raid_map) { 4617 ret = -ENOMEM; 4618 goto out; 4619 } 4620 4621 /* Work out the disk rotation on this stripe-set */ 4622 tmp = stripe_nr; 4623 rot = do_div(tmp, num_stripes); 4624 4625 /* Fill in the logical address of each stripe */ 4626 tmp = stripe_nr * nr_data_stripes(map); 4627 for (i = 0; i < nr_data_stripes(map); i++) 4628 raid_map[(i+rot) % num_stripes] = 4629 em->start + (tmp + i) * map->stripe_len; 4630 4631 raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE; 4632 if (map->type & BTRFS_BLOCK_GROUP_RAID6) 4633 raid_map[(i+rot+1) % num_stripes] = 4634 RAID6_Q_STRIPE; 4635 4636 *length = map->stripe_len; 4637 stripe_index = 0; 4638 stripe_offset = 0; 4639 } else { 4640 /* 4641 * Mirror #0 or #1 means the original data block. 4642 * Mirror #2 is RAID5 parity block. 4643 * Mirror #3 is RAID6 Q block. 4644 */ 4645 stripe_index = do_div(stripe_nr, nr_data_stripes(map)); 4646 if (mirror_num > 1) 4647 stripe_index = nr_data_stripes(map) + 4648 mirror_num - 2; 4649 4650 /* We distribute the parity blocks across stripes */ 4651 tmp = stripe_nr + stripe_index; 4652 stripe_index = do_div(tmp, map->num_stripes); 4653 } 4654 } else { 4655 /* 4656 * after this do_div call, stripe_nr is the number of stripes 4657 * on this device we have to walk to find the data, and 4658 * stripe_index is the number of our device in the stripe array 4659 */ 4660 stripe_index = do_div(stripe_nr, map->num_stripes); 4661 mirror_num = stripe_index + 1; 4662 } 4663 BUG_ON(stripe_index >= map->num_stripes); 4664 4665 num_alloc_stripes = num_stripes; 4666 if (dev_replace_is_ongoing) { 4667 if (rw & (REQ_WRITE | REQ_DISCARD)) 4668 num_alloc_stripes <<= 1; 4669 if (rw & REQ_GET_READ_MIRRORS) 4670 num_alloc_stripes++; 4671 } 4672 bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS); 4673 if (!bbio) { 4674 ret = -ENOMEM; 4675 goto out; 4676 } 4677 atomic_set(&bbio->error, 0); 4678 4679 if (rw & REQ_DISCARD) { 4680 int factor = 0; 4681 int sub_stripes = 0; 4682 u64 stripes_per_dev = 0; 4683 u32 remaining_stripes = 0; 4684 u32 last_stripe = 0; 4685 4686 if (map->type & 4687 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { 4688 if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4689 sub_stripes = 1; 4690 else 4691 sub_stripes = map->sub_stripes; 4692 4693 factor = map->num_stripes / sub_stripes; 4694 stripes_per_dev = div_u64_rem(stripe_nr_end - 4695 stripe_nr_orig, 4696 factor, 4697 &remaining_stripes); 4698 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe); 4699 last_stripe *= sub_stripes; 4700 } 4701 4702 for (i = 0; i < num_stripes; i++) { 4703 bbio->stripes[i].physical = 4704 map->stripes[stripe_index].physical + 4705 stripe_offset + stripe_nr * map->stripe_len; 4706 bbio->stripes[i].dev = map->stripes[stripe_index].dev; 4707 4708 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | 4709 BTRFS_BLOCK_GROUP_RAID10)) { 4710 bbio->stripes[i].length = stripes_per_dev * 4711 map->stripe_len; 4712 4713 if (i / sub_stripes < remaining_stripes) 4714 bbio->stripes[i].length += 4715 map->stripe_len; 4716 4717 /* 4718 * Special for the first stripe and 4719 * the last stripe: 4720 * 4721 * |-------|...|-------| 4722 * |----------| 4723 * off end_off 4724 */ 4725 if (i < sub_stripes) 4726 bbio->stripes[i].length -= 4727 stripe_offset; 4728 4729 if (stripe_index >= last_stripe && 4730 stripe_index <= (last_stripe + 4731 sub_stripes - 1)) 4732 bbio->stripes[i].length -= 4733 stripe_end_offset; 4734 4735 if (i == sub_stripes - 1) 4736 stripe_offset = 0; 4737 } else 4738 bbio->stripes[i].length = *length; 4739 4740 stripe_index++; 4741 if (stripe_index == map->num_stripes) { 4742 /* This could only happen for RAID0/10 */ 4743 stripe_index = 0; 4744 stripe_nr++; 4745 } 4746 } 4747 } else { 4748 for (i = 0; i < num_stripes; i++) { 4749 bbio->stripes[i].physical = 4750 map->stripes[stripe_index].physical + 4751 stripe_offset + 4752 stripe_nr * map->stripe_len; 4753 bbio->stripes[i].dev = 4754 map->stripes[stripe_index].dev; 4755 stripe_index++; 4756 } 4757 } 4758 4759 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) { 4760 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | 4761 BTRFS_BLOCK_GROUP_RAID10 | 4762 BTRFS_BLOCK_GROUP_RAID5 | 4763 BTRFS_BLOCK_GROUP_DUP)) { 4764 max_errors = 1; 4765 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) { 4766 max_errors = 2; 4767 } 4768 } 4769 4770 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) && 4771 dev_replace->tgtdev != NULL) { 4772 int index_where_to_add; 4773 u64 srcdev_devid = dev_replace->srcdev->devid; 4774 4775 /* 4776 * duplicate the write operations while the dev replace 4777 * procedure is running. Since the copying of the old disk 4778 * to the new disk takes place at run time while the 4779 * filesystem is mounted writable, the regular write 4780 * operations to the old disk have to be duplicated to go 4781 * to the new disk as well. 4782 * Note that device->missing is handled by the caller, and 4783 * that the write to the old disk is already set up in the 4784 * stripes array. 4785 */ 4786 index_where_to_add = num_stripes; 4787 for (i = 0; i < num_stripes; i++) { 4788 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4789 /* write to new disk, too */ 4790 struct btrfs_bio_stripe *new = 4791 bbio->stripes + index_where_to_add; 4792 struct btrfs_bio_stripe *old = 4793 bbio->stripes + i; 4794 4795 new->physical = old->physical; 4796 new->length = old->length; 4797 new->dev = dev_replace->tgtdev; 4798 index_where_to_add++; 4799 max_errors++; 4800 } 4801 } 4802 num_stripes = index_where_to_add; 4803 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) && 4804 dev_replace->tgtdev != NULL) { 4805 u64 srcdev_devid = dev_replace->srcdev->devid; 4806 int index_srcdev = 0; 4807 int found = 0; 4808 u64 physical_of_found = 0; 4809 4810 /* 4811 * During the dev-replace procedure, the target drive can 4812 * also be used to read data in case it is needed to repair 4813 * a corrupt block elsewhere. This is possible if the 4814 * requested area is left of the left cursor. In this area, 4815 * the target drive is a full copy of the source drive. 4816 */ 4817 for (i = 0; i < num_stripes; i++) { 4818 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4819 /* 4820 * In case of DUP, in order to keep it 4821 * simple, only add the mirror with the 4822 * lowest physical address 4823 */ 4824 if (found && 4825 physical_of_found <= 4826 bbio->stripes[i].physical) 4827 continue; 4828 index_srcdev = i; 4829 found = 1; 4830 physical_of_found = bbio->stripes[i].physical; 4831 } 4832 } 4833 if (found) { 4834 u64 length = map->stripe_len; 4835 4836 if (physical_of_found + length <= 4837 dev_replace->cursor_left) { 4838 struct btrfs_bio_stripe *tgtdev_stripe = 4839 bbio->stripes + num_stripes; 4840 4841 tgtdev_stripe->physical = physical_of_found; 4842 tgtdev_stripe->length = 4843 bbio->stripes[index_srcdev].length; 4844 tgtdev_stripe->dev = dev_replace->tgtdev; 4845 4846 num_stripes++; 4847 } 4848 } 4849 } 4850 4851 *bbio_ret = bbio; 4852 bbio->num_stripes = num_stripes; 4853 bbio->max_errors = max_errors; 4854 bbio->mirror_num = mirror_num; 4855 4856 /* 4857 * this is the case that REQ_READ && dev_replace_is_ongoing && 4858 * mirror_num == num_stripes + 1 && dev_replace target drive is 4859 * available as a mirror 4860 */ 4861 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) { 4862 WARN_ON(num_stripes > 1); 4863 bbio->stripes[0].dev = dev_replace->tgtdev; 4864 bbio->stripes[0].physical = physical_to_patch_in_first_stripe; 4865 bbio->mirror_num = map->num_stripes + 1; 4866 } 4867 if (raid_map) { 4868 sort_parity_stripes(bbio, raid_map); 4869 *raid_map_ret = raid_map; 4870 } 4871 out: 4872 if (dev_replace_is_ongoing) 4873 btrfs_dev_replace_unlock(dev_replace); 4874 free_extent_map(em); 4875 return ret; 4876 } 4877 4878 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4879 u64 logical, u64 *length, 4880 struct btrfs_bio **bbio_ret, int mirror_num) 4881 { 4882 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret, 4883 mirror_num, NULL); 4884 } 4885 4886 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, 4887 u64 chunk_start, u64 physical, u64 devid, 4888 u64 **logical, int *naddrs, int *stripe_len) 4889 { 4890 struct extent_map_tree *em_tree = &map_tree->map_tree; 4891 struct extent_map *em; 4892 struct map_lookup *map; 4893 u64 *buf; 4894 u64 bytenr; 4895 u64 length; 4896 u64 stripe_nr; 4897 u64 rmap_len; 4898 int i, j, nr = 0; 4899 4900 read_lock(&em_tree->lock); 4901 em = lookup_extent_mapping(em_tree, chunk_start, 1); 4902 read_unlock(&em_tree->lock); 4903 4904 if (!em) { 4905 printk(KERN_ERR "btrfs: couldn't find em for chunk %Lu\n", 4906 chunk_start); 4907 return -EIO; 4908 } 4909 4910 if (em->start != chunk_start) { 4911 printk(KERN_ERR "btrfs: bad chunk start, em=%Lu, wanted=%Lu\n", 4912 em->start, chunk_start); 4913 free_extent_map(em); 4914 return -EIO; 4915 } 4916 map = (struct map_lookup *)em->bdev; 4917 4918 length = em->len; 4919 rmap_len = map->stripe_len; 4920 4921 if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4922 do_div(length, map->num_stripes / map->sub_stripes); 4923 else if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4924 do_div(length, map->num_stripes); 4925 else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4926 BTRFS_BLOCK_GROUP_RAID6)) { 4927 do_div(length, nr_data_stripes(map)); 4928 rmap_len = map->stripe_len * nr_data_stripes(map); 4929 } 4930 4931 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); 4932 BUG_ON(!buf); /* -ENOMEM */ 4933 4934 for (i = 0; i < map->num_stripes; i++) { 4935 if (devid && map->stripes[i].dev->devid != devid) 4936 continue; 4937 if (map->stripes[i].physical > physical || 4938 map->stripes[i].physical + length <= physical) 4939 continue; 4940 4941 stripe_nr = physical - map->stripes[i].physical; 4942 do_div(stripe_nr, map->stripe_len); 4943 4944 if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4945 stripe_nr = stripe_nr * map->num_stripes + i; 4946 do_div(stripe_nr, map->sub_stripes); 4947 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4948 stripe_nr = stripe_nr * map->num_stripes + i; 4949 } /* else if RAID[56], multiply by nr_data_stripes(). 4950 * Alternatively, just use rmap_len below instead of 4951 * map->stripe_len */ 4952 4953 bytenr = chunk_start + stripe_nr * rmap_len; 4954 WARN_ON(nr >= map->num_stripes); 4955 for (j = 0; j < nr; j++) { 4956 if (buf[j] == bytenr) 4957 break; 4958 } 4959 if (j == nr) { 4960 WARN_ON(nr >= map->num_stripes); 4961 buf[nr++] = bytenr; 4962 } 4963 } 4964 4965 *logical = buf; 4966 *naddrs = nr; 4967 *stripe_len = rmap_len; 4968 4969 free_extent_map(em); 4970 return 0; 4971 } 4972 4973 static void btrfs_end_bio(struct bio *bio, int err) 4974 { 4975 struct btrfs_bio *bbio = bio->bi_private; 4976 int is_orig_bio = 0; 4977 4978 if (err) { 4979 atomic_inc(&bbio->error); 4980 if (err == -EIO || err == -EREMOTEIO) { 4981 unsigned int stripe_index = 4982 btrfs_io_bio(bio)->stripe_index; 4983 struct btrfs_device *dev; 4984 4985 BUG_ON(stripe_index >= bbio->num_stripes); 4986 dev = bbio->stripes[stripe_index].dev; 4987 if (dev->bdev) { 4988 if (bio->bi_rw & WRITE) 4989 btrfs_dev_stat_inc(dev, 4990 BTRFS_DEV_STAT_WRITE_ERRS); 4991 else 4992 btrfs_dev_stat_inc(dev, 4993 BTRFS_DEV_STAT_READ_ERRS); 4994 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH) 4995 btrfs_dev_stat_inc(dev, 4996 BTRFS_DEV_STAT_FLUSH_ERRS); 4997 btrfs_dev_stat_print_on_error(dev); 4998 } 4999 } 5000 } 5001 5002 if (bio == bbio->orig_bio) 5003 is_orig_bio = 1; 5004 5005 if (atomic_dec_and_test(&bbio->stripes_pending)) { 5006 if (!is_orig_bio) { 5007 bio_put(bio); 5008 bio = bbio->orig_bio; 5009 } 5010 bio->bi_private = bbio->private; 5011 bio->bi_end_io = bbio->end_io; 5012 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num; 5013 /* only send an error to the higher layers if it is 5014 * beyond the tolerance of the btrfs bio 5015 */ 5016 if (atomic_read(&bbio->error) > bbio->max_errors) { 5017 err = -EIO; 5018 } else { 5019 /* 5020 * this bio is actually up to date, we didn't 5021 * go over the max number of errors 5022 */ 5023 set_bit(BIO_UPTODATE, &bio->bi_flags); 5024 err = 0; 5025 } 5026 kfree(bbio); 5027 5028 bio_endio(bio, err); 5029 } else if (!is_orig_bio) { 5030 bio_put(bio); 5031 } 5032 } 5033 5034 struct async_sched { 5035 struct bio *bio; 5036 int rw; 5037 struct btrfs_fs_info *info; 5038 struct btrfs_work work; 5039 }; 5040 5041 /* 5042 * see run_scheduled_bios for a description of why bios are collected for 5043 * async submit. 5044 * 5045 * This will add one bio to the pending list for a device and make sure 5046 * the work struct is scheduled. 5047 */ 5048 static noinline void btrfs_schedule_bio(struct btrfs_root *root, 5049 struct btrfs_device *device, 5050 int rw, struct bio *bio) 5051 { 5052 int should_queue = 1; 5053 struct btrfs_pending_bios *pending_bios; 5054 5055 if (device->missing || !device->bdev) { 5056 bio_endio(bio, -EIO); 5057 return; 5058 } 5059 5060 /* don't bother with additional async steps for reads, right now */ 5061 if (!(rw & REQ_WRITE)) { 5062 bio_get(bio); 5063 btrfsic_submit_bio(rw, bio); 5064 bio_put(bio); 5065 return; 5066 } 5067 5068 /* 5069 * nr_async_bios allows us to reliably return congestion to the 5070 * higher layers. Otherwise, the async bio makes it appear we have 5071 * made progress against dirty pages when we've really just put it 5072 * on a queue for later 5073 */ 5074 atomic_inc(&root->fs_info->nr_async_bios); 5075 WARN_ON(bio->bi_next); 5076 bio->bi_next = NULL; 5077 bio->bi_rw |= rw; 5078 5079 spin_lock(&device->io_lock); 5080 if (bio->bi_rw & REQ_SYNC) 5081 pending_bios = &device->pending_sync_bios; 5082 else 5083 pending_bios = &device->pending_bios; 5084 5085 if (pending_bios->tail) 5086 pending_bios->tail->bi_next = bio; 5087 5088 pending_bios->tail = bio; 5089 if (!pending_bios->head) 5090 pending_bios->head = bio; 5091 if (device->running_pending) 5092 should_queue = 0; 5093 5094 spin_unlock(&device->io_lock); 5095 5096 if (should_queue) 5097 btrfs_queue_worker(&root->fs_info->submit_workers, 5098 &device->work); 5099 } 5100 5101 static int bio_size_ok(struct block_device *bdev, struct bio *bio, 5102 sector_t sector) 5103 { 5104 struct bio_vec *prev; 5105 struct request_queue *q = bdev_get_queue(bdev); 5106 unsigned short max_sectors = queue_max_sectors(q); 5107 struct bvec_merge_data bvm = { 5108 .bi_bdev = bdev, 5109 .bi_sector = sector, 5110 .bi_rw = bio->bi_rw, 5111 }; 5112 5113 if (bio->bi_vcnt == 0) { 5114 WARN_ON(1); 5115 return 1; 5116 } 5117 5118 prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; 5119 if (bio_sectors(bio) > max_sectors) 5120 return 0; 5121 5122 if (!q->merge_bvec_fn) 5123 return 1; 5124 5125 bvm.bi_size = bio->bi_size - prev->bv_len; 5126 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) 5127 return 0; 5128 return 1; 5129 } 5130 5131 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 5132 struct bio *bio, u64 physical, int dev_nr, 5133 int rw, int async) 5134 { 5135 struct btrfs_device *dev = bbio->stripes[dev_nr].dev; 5136 5137 bio->bi_private = bbio; 5138 btrfs_io_bio(bio)->stripe_index = dev_nr; 5139 bio->bi_end_io = btrfs_end_bio; 5140 bio->bi_sector = physical >> 9; 5141 #ifdef DEBUG 5142 { 5143 struct rcu_string *name; 5144 5145 rcu_read_lock(); 5146 name = rcu_dereference(dev->name); 5147 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu " 5148 "(%s id %llu), size=%u\n", rw, 5149 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, 5150 name->str, dev->devid, bio->bi_size); 5151 rcu_read_unlock(); 5152 } 5153 #endif 5154 bio->bi_bdev = dev->bdev; 5155 if (async) 5156 btrfs_schedule_bio(root, dev, rw, bio); 5157 else 5158 btrfsic_submit_bio(rw, bio); 5159 } 5160 5161 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 5162 struct bio *first_bio, struct btrfs_device *dev, 5163 int dev_nr, int rw, int async) 5164 { 5165 struct bio_vec *bvec = first_bio->bi_io_vec; 5166 struct bio *bio; 5167 int nr_vecs = bio_get_nr_vecs(dev->bdev); 5168 u64 physical = bbio->stripes[dev_nr].physical; 5169 5170 again: 5171 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS); 5172 if (!bio) 5173 return -ENOMEM; 5174 5175 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) { 5176 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len, 5177 bvec->bv_offset) < bvec->bv_len) { 5178 u64 len = bio->bi_size; 5179 5180 atomic_inc(&bbio->stripes_pending); 5181 submit_stripe_bio(root, bbio, bio, physical, dev_nr, 5182 rw, async); 5183 physical += len; 5184 goto again; 5185 } 5186 bvec++; 5187 } 5188 5189 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async); 5190 return 0; 5191 } 5192 5193 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) 5194 { 5195 atomic_inc(&bbio->error); 5196 if (atomic_dec_and_test(&bbio->stripes_pending)) { 5197 bio->bi_private = bbio->private; 5198 bio->bi_end_io = bbio->end_io; 5199 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num; 5200 bio->bi_sector = logical >> 9; 5201 kfree(bbio); 5202 bio_endio(bio, -EIO); 5203 } 5204 } 5205 5206 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, 5207 int mirror_num, int async_submit) 5208 { 5209 struct btrfs_device *dev; 5210 struct bio *first_bio = bio; 5211 u64 logical = (u64)bio->bi_sector << 9; 5212 u64 length = 0; 5213 u64 map_length; 5214 u64 *raid_map = NULL; 5215 int ret; 5216 int dev_nr = 0; 5217 int total_devs = 1; 5218 struct btrfs_bio *bbio = NULL; 5219 5220 length = bio->bi_size; 5221 map_length = length; 5222 5223 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio, 5224 mirror_num, &raid_map); 5225 if (ret) /* -ENOMEM */ 5226 return ret; 5227 5228 total_devs = bbio->num_stripes; 5229 bbio->orig_bio = first_bio; 5230 bbio->private = first_bio->bi_private; 5231 bbio->end_io = first_bio->bi_end_io; 5232 atomic_set(&bbio->stripes_pending, bbio->num_stripes); 5233 5234 if (raid_map) { 5235 /* In this case, map_length has been set to the length of 5236 a single stripe; not the whole write */ 5237 if (rw & WRITE) { 5238 return raid56_parity_write(root, bio, bbio, 5239 raid_map, map_length); 5240 } else { 5241 return raid56_parity_recover(root, bio, bbio, 5242 raid_map, map_length, 5243 mirror_num); 5244 } 5245 } 5246 5247 if (map_length < length) { 5248 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu", 5249 (unsigned long long)logical, 5250 (unsigned long long)length, 5251 (unsigned long long)map_length); 5252 BUG(); 5253 } 5254 5255 while (dev_nr < total_devs) { 5256 dev = bbio->stripes[dev_nr].dev; 5257 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) { 5258 bbio_error(bbio, first_bio, logical); 5259 dev_nr++; 5260 continue; 5261 } 5262 5263 /* 5264 * Check and see if we're ok with this bio based on it's size 5265 * and offset with the given device. 5266 */ 5267 if (!bio_size_ok(dev->bdev, first_bio, 5268 bbio->stripes[dev_nr].physical >> 9)) { 5269 ret = breakup_stripe_bio(root, bbio, first_bio, dev, 5270 dev_nr, rw, async_submit); 5271 BUG_ON(ret); 5272 dev_nr++; 5273 continue; 5274 } 5275 5276 if (dev_nr < total_devs - 1) { 5277 bio = btrfs_bio_clone(first_bio, GFP_NOFS); 5278 BUG_ON(!bio); /* -ENOMEM */ 5279 } else { 5280 bio = first_bio; 5281 } 5282 5283 submit_stripe_bio(root, bbio, bio, 5284 bbio->stripes[dev_nr].physical, dev_nr, rw, 5285 async_submit); 5286 dev_nr++; 5287 } 5288 return 0; 5289 } 5290 5291 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, 5292 u8 *uuid, u8 *fsid) 5293 { 5294 struct btrfs_device *device; 5295 struct btrfs_fs_devices *cur_devices; 5296 5297 cur_devices = fs_info->fs_devices; 5298 while (cur_devices) { 5299 if (!fsid || 5300 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5301 device = __find_device(&cur_devices->devices, 5302 devid, uuid); 5303 if (device) 5304 return device; 5305 } 5306 cur_devices = cur_devices->seed; 5307 } 5308 return NULL; 5309 } 5310 5311 static struct btrfs_device *add_missing_dev(struct btrfs_root *root, 5312 u64 devid, u8 *dev_uuid) 5313 { 5314 struct btrfs_device *device; 5315 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5316 5317 device = kzalloc(sizeof(*device), GFP_NOFS); 5318 if (!device) 5319 return NULL; 5320 list_add(&device->dev_list, 5321 &fs_devices->devices); 5322 device->devid = devid; 5323 device->work.func = pending_bios_fn; 5324 device->fs_devices = fs_devices; 5325 device->missing = 1; 5326 fs_devices->num_devices++; 5327 fs_devices->missing_devices++; 5328 spin_lock_init(&device->io_lock); 5329 INIT_LIST_HEAD(&device->dev_alloc_list); 5330 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE); 5331 return device; 5332 } 5333 5334 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, 5335 struct extent_buffer *leaf, 5336 struct btrfs_chunk *chunk) 5337 { 5338 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 5339 struct map_lookup *map; 5340 struct extent_map *em; 5341 u64 logical; 5342 u64 length; 5343 u64 devid; 5344 u8 uuid[BTRFS_UUID_SIZE]; 5345 int num_stripes; 5346 int ret; 5347 int i; 5348 5349 logical = key->offset; 5350 length = btrfs_chunk_length(leaf, chunk); 5351 5352 read_lock(&map_tree->map_tree.lock); 5353 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1); 5354 read_unlock(&map_tree->map_tree.lock); 5355 5356 /* already mapped? */ 5357 if (em && em->start <= logical && em->start + em->len > logical) { 5358 free_extent_map(em); 5359 return 0; 5360 } else if (em) { 5361 free_extent_map(em); 5362 } 5363 5364 em = alloc_extent_map(); 5365 if (!em) 5366 return -ENOMEM; 5367 num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 5368 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 5369 if (!map) { 5370 free_extent_map(em); 5371 return -ENOMEM; 5372 } 5373 5374 em->bdev = (struct block_device *)map; 5375 em->start = logical; 5376 em->len = length; 5377 em->orig_start = 0; 5378 em->block_start = 0; 5379 em->block_len = em->len; 5380 5381 map->num_stripes = num_stripes; 5382 map->io_width = btrfs_chunk_io_width(leaf, chunk); 5383 map->io_align = btrfs_chunk_io_align(leaf, chunk); 5384 map->sector_size = btrfs_chunk_sector_size(leaf, chunk); 5385 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); 5386 map->type = btrfs_chunk_type(leaf, chunk); 5387 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); 5388 for (i = 0; i < num_stripes; i++) { 5389 map->stripes[i].physical = 5390 btrfs_stripe_offset_nr(leaf, chunk, i); 5391 devid = btrfs_stripe_devid_nr(leaf, chunk, i); 5392 read_extent_buffer(leaf, uuid, (unsigned long) 5393 btrfs_stripe_dev_uuid_nr(chunk, i), 5394 BTRFS_UUID_SIZE); 5395 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid, 5396 uuid, NULL); 5397 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) { 5398 kfree(map); 5399 free_extent_map(em); 5400 return -EIO; 5401 } 5402 if (!map->stripes[i].dev) { 5403 map->stripes[i].dev = 5404 add_missing_dev(root, devid, uuid); 5405 if (!map->stripes[i].dev) { 5406 kfree(map); 5407 free_extent_map(em); 5408 return -EIO; 5409 } 5410 } 5411 map->stripes[i].dev->in_fs_metadata = 1; 5412 } 5413 5414 write_lock(&map_tree->map_tree.lock); 5415 ret = add_extent_mapping(&map_tree->map_tree, em, 0); 5416 write_unlock(&map_tree->map_tree.lock); 5417 BUG_ON(ret); /* Tree corruption */ 5418 free_extent_map(em); 5419 5420 return 0; 5421 } 5422 5423 static void fill_device_from_item(struct extent_buffer *leaf, 5424 struct btrfs_dev_item *dev_item, 5425 struct btrfs_device *device) 5426 { 5427 unsigned long ptr; 5428 5429 device->devid = btrfs_device_id(leaf, dev_item); 5430 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); 5431 device->total_bytes = device->disk_total_bytes; 5432 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); 5433 device->type = btrfs_device_type(leaf, dev_item); 5434 device->io_align = btrfs_device_io_align(leaf, dev_item); 5435 device->io_width = btrfs_device_io_width(leaf, dev_item); 5436 device->sector_size = btrfs_device_sector_size(leaf, dev_item); 5437 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); 5438 device->is_tgtdev_for_dev_replace = 0; 5439 5440 ptr = (unsigned long)btrfs_device_uuid(dev_item); 5441 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 5442 } 5443 5444 static int open_seed_devices(struct btrfs_root *root, u8 *fsid) 5445 { 5446 struct btrfs_fs_devices *fs_devices; 5447 int ret; 5448 5449 BUG_ON(!mutex_is_locked(&uuid_mutex)); 5450 5451 fs_devices = root->fs_info->fs_devices->seed; 5452 while (fs_devices) { 5453 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5454 ret = 0; 5455 goto out; 5456 } 5457 fs_devices = fs_devices->seed; 5458 } 5459 5460 fs_devices = find_fsid(fsid); 5461 if (!fs_devices) { 5462 ret = -ENOENT; 5463 goto out; 5464 } 5465 5466 fs_devices = clone_fs_devices(fs_devices); 5467 if (IS_ERR(fs_devices)) { 5468 ret = PTR_ERR(fs_devices); 5469 goto out; 5470 } 5471 5472 ret = __btrfs_open_devices(fs_devices, FMODE_READ, 5473 root->fs_info->bdev_holder); 5474 if (ret) { 5475 free_fs_devices(fs_devices); 5476 goto out; 5477 } 5478 5479 if (!fs_devices->seeding) { 5480 __btrfs_close_devices(fs_devices); 5481 free_fs_devices(fs_devices); 5482 ret = -EINVAL; 5483 goto out; 5484 } 5485 5486 fs_devices->seed = root->fs_info->fs_devices->seed; 5487 root->fs_info->fs_devices->seed = fs_devices; 5488 out: 5489 return ret; 5490 } 5491 5492 static int read_one_dev(struct btrfs_root *root, 5493 struct extent_buffer *leaf, 5494 struct btrfs_dev_item *dev_item) 5495 { 5496 struct btrfs_device *device; 5497 u64 devid; 5498 int ret; 5499 u8 fs_uuid[BTRFS_UUID_SIZE]; 5500 u8 dev_uuid[BTRFS_UUID_SIZE]; 5501 5502 devid = btrfs_device_id(leaf, dev_item); 5503 read_extent_buffer(leaf, dev_uuid, 5504 (unsigned long)btrfs_device_uuid(dev_item), 5505 BTRFS_UUID_SIZE); 5506 read_extent_buffer(leaf, fs_uuid, 5507 (unsigned long)btrfs_device_fsid(dev_item), 5508 BTRFS_UUID_SIZE); 5509 5510 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) { 5511 ret = open_seed_devices(root, fs_uuid); 5512 if (ret && !btrfs_test_opt(root, DEGRADED)) 5513 return ret; 5514 } 5515 5516 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid); 5517 if (!device || !device->bdev) { 5518 if (!btrfs_test_opt(root, DEGRADED)) 5519 return -EIO; 5520 5521 if (!device) { 5522 btrfs_warn(root->fs_info, "devid %llu missing", 5523 (unsigned long long)devid); 5524 device = add_missing_dev(root, devid, dev_uuid); 5525 if (!device) 5526 return -ENOMEM; 5527 } else if (!device->missing) { 5528 /* 5529 * this happens when a device that was properly setup 5530 * in the device info lists suddenly goes bad. 5531 * device->bdev is NULL, and so we have to set 5532 * device->missing to one here 5533 */ 5534 root->fs_info->fs_devices->missing_devices++; 5535 device->missing = 1; 5536 } 5537 } 5538 5539 if (device->fs_devices != root->fs_info->fs_devices) { 5540 BUG_ON(device->writeable); 5541 if (device->generation != 5542 btrfs_device_generation(leaf, dev_item)) 5543 return -EINVAL; 5544 } 5545 5546 fill_device_from_item(leaf, dev_item, device); 5547 device->in_fs_metadata = 1; 5548 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 5549 device->fs_devices->total_rw_bytes += device->total_bytes; 5550 spin_lock(&root->fs_info->free_chunk_lock); 5551 root->fs_info->free_chunk_space += device->total_bytes - 5552 device->bytes_used; 5553 spin_unlock(&root->fs_info->free_chunk_lock); 5554 } 5555 ret = 0; 5556 return ret; 5557 } 5558 5559 int btrfs_read_sys_array(struct btrfs_root *root) 5560 { 5561 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 5562 struct extent_buffer *sb; 5563 struct btrfs_disk_key *disk_key; 5564 struct btrfs_chunk *chunk; 5565 u8 *ptr; 5566 unsigned long sb_ptr; 5567 int ret = 0; 5568 u32 num_stripes; 5569 u32 array_size; 5570 u32 len = 0; 5571 u32 cur; 5572 struct btrfs_key key; 5573 5574 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET, 5575 BTRFS_SUPER_INFO_SIZE); 5576 if (!sb) 5577 return -ENOMEM; 5578 btrfs_set_buffer_uptodate(sb); 5579 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); 5580 /* 5581 * The sb extent buffer is artifical and just used to read the system array. 5582 * btrfs_set_buffer_uptodate() call does not properly mark all it's 5583 * pages up-to-date when the page is larger: extent does not cover the 5584 * whole page and consequently check_page_uptodate does not find all 5585 * the page's extents up-to-date (the hole beyond sb), 5586 * write_extent_buffer then triggers a WARN_ON. 5587 * 5588 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle, 5589 * but sb spans only this function. Add an explicit SetPageUptodate call 5590 * to silence the warning eg. on PowerPC 64. 5591 */ 5592 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE) 5593 SetPageUptodate(sb->pages[0]); 5594 5595 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); 5596 array_size = btrfs_super_sys_array_size(super_copy); 5597 5598 ptr = super_copy->sys_chunk_array; 5599 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array); 5600 cur = 0; 5601 5602 while (cur < array_size) { 5603 disk_key = (struct btrfs_disk_key *)ptr; 5604 btrfs_disk_key_to_cpu(&key, disk_key); 5605 5606 len = sizeof(*disk_key); ptr += len; 5607 sb_ptr += len; 5608 cur += len; 5609 5610 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 5611 chunk = (struct btrfs_chunk *)sb_ptr; 5612 ret = read_one_chunk(root, &key, sb, chunk); 5613 if (ret) 5614 break; 5615 num_stripes = btrfs_chunk_num_stripes(sb, chunk); 5616 len = btrfs_chunk_item_size(num_stripes); 5617 } else { 5618 ret = -EIO; 5619 break; 5620 } 5621 ptr += len; 5622 sb_ptr += len; 5623 cur += len; 5624 } 5625 free_extent_buffer(sb); 5626 return ret; 5627 } 5628 5629 int btrfs_read_chunk_tree(struct btrfs_root *root) 5630 { 5631 struct btrfs_path *path; 5632 struct extent_buffer *leaf; 5633 struct btrfs_key key; 5634 struct btrfs_key found_key; 5635 int ret; 5636 int slot; 5637 5638 root = root->fs_info->chunk_root; 5639 5640 path = btrfs_alloc_path(); 5641 if (!path) 5642 return -ENOMEM; 5643 5644 mutex_lock(&uuid_mutex); 5645 lock_chunks(root); 5646 5647 /* first we search for all of the device items, and then we 5648 * read in all of the chunk items. This way we can create chunk 5649 * mappings that reference all of the devices that are afound 5650 */ 5651 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 5652 key.offset = 0; 5653 key.type = 0; 5654 again: 5655 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5656 if (ret < 0) 5657 goto error; 5658 while (1) { 5659 leaf = path->nodes[0]; 5660 slot = path->slots[0]; 5661 if (slot >= btrfs_header_nritems(leaf)) { 5662 ret = btrfs_next_leaf(root, path); 5663 if (ret == 0) 5664 continue; 5665 if (ret < 0) 5666 goto error; 5667 break; 5668 } 5669 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5670 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5671 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID) 5672 break; 5673 if (found_key.type == BTRFS_DEV_ITEM_KEY) { 5674 struct btrfs_dev_item *dev_item; 5675 dev_item = btrfs_item_ptr(leaf, slot, 5676 struct btrfs_dev_item); 5677 ret = read_one_dev(root, leaf, dev_item); 5678 if (ret) 5679 goto error; 5680 } 5681 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { 5682 struct btrfs_chunk *chunk; 5683 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 5684 ret = read_one_chunk(root, &found_key, leaf, chunk); 5685 if (ret) 5686 goto error; 5687 } 5688 path->slots[0]++; 5689 } 5690 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5691 key.objectid = 0; 5692 btrfs_release_path(path); 5693 goto again; 5694 } 5695 ret = 0; 5696 error: 5697 unlock_chunks(root); 5698 mutex_unlock(&uuid_mutex); 5699 5700 btrfs_free_path(path); 5701 return ret; 5702 } 5703 5704 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info) 5705 { 5706 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5707 struct btrfs_device *device; 5708 5709 mutex_lock(&fs_devices->device_list_mutex); 5710 list_for_each_entry(device, &fs_devices->devices, dev_list) 5711 device->dev_root = fs_info->dev_root; 5712 mutex_unlock(&fs_devices->device_list_mutex); 5713 } 5714 5715 static void __btrfs_reset_dev_stats(struct btrfs_device *dev) 5716 { 5717 int i; 5718 5719 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5720 btrfs_dev_stat_reset(dev, i); 5721 } 5722 5723 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) 5724 { 5725 struct btrfs_key key; 5726 struct btrfs_key found_key; 5727 struct btrfs_root *dev_root = fs_info->dev_root; 5728 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5729 struct extent_buffer *eb; 5730 int slot; 5731 int ret = 0; 5732 struct btrfs_device *device; 5733 struct btrfs_path *path = NULL; 5734 int i; 5735 5736 path = btrfs_alloc_path(); 5737 if (!path) { 5738 ret = -ENOMEM; 5739 goto out; 5740 } 5741 5742 mutex_lock(&fs_devices->device_list_mutex); 5743 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5744 int item_size; 5745 struct btrfs_dev_stats_item *ptr; 5746 5747 key.objectid = 0; 5748 key.type = BTRFS_DEV_STATS_KEY; 5749 key.offset = device->devid; 5750 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 5751 if (ret) { 5752 __btrfs_reset_dev_stats(device); 5753 device->dev_stats_valid = 1; 5754 btrfs_release_path(path); 5755 continue; 5756 } 5757 slot = path->slots[0]; 5758 eb = path->nodes[0]; 5759 btrfs_item_key_to_cpu(eb, &found_key, slot); 5760 item_size = btrfs_item_size_nr(eb, slot); 5761 5762 ptr = btrfs_item_ptr(eb, slot, 5763 struct btrfs_dev_stats_item); 5764 5765 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5766 if (item_size >= (1 + i) * sizeof(__le64)) 5767 btrfs_dev_stat_set(device, i, 5768 btrfs_dev_stats_value(eb, ptr, i)); 5769 else 5770 btrfs_dev_stat_reset(device, i); 5771 } 5772 5773 device->dev_stats_valid = 1; 5774 btrfs_dev_stat_print_on_load(device); 5775 btrfs_release_path(path); 5776 } 5777 mutex_unlock(&fs_devices->device_list_mutex); 5778 5779 out: 5780 btrfs_free_path(path); 5781 return ret < 0 ? ret : 0; 5782 } 5783 5784 static int update_dev_stat_item(struct btrfs_trans_handle *trans, 5785 struct btrfs_root *dev_root, 5786 struct btrfs_device *device) 5787 { 5788 struct btrfs_path *path; 5789 struct btrfs_key key; 5790 struct extent_buffer *eb; 5791 struct btrfs_dev_stats_item *ptr; 5792 int ret; 5793 int i; 5794 5795 key.objectid = 0; 5796 key.type = BTRFS_DEV_STATS_KEY; 5797 key.offset = device->devid; 5798 5799 path = btrfs_alloc_path(); 5800 BUG_ON(!path); 5801 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 5802 if (ret < 0) { 5803 printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n", 5804 ret, rcu_str_deref(device->name)); 5805 goto out; 5806 } 5807 5808 if (ret == 0 && 5809 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 5810 /* need to delete old one and insert a new one */ 5811 ret = btrfs_del_item(trans, dev_root, path); 5812 if (ret != 0) { 5813 printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n", 5814 rcu_str_deref(device->name), ret); 5815 goto out; 5816 } 5817 ret = 1; 5818 } 5819 5820 if (ret == 1) { 5821 /* need to insert a new item */ 5822 btrfs_release_path(path); 5823 ret = btrfs_insert_empty_item(trans, dev_root, path, 5824 &key, sizeof(*ptr)); 5825 if (ret < 0) { 5826 printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n", 5827 rcu_str_deref(device->name), ret); 5828 goto out; 5829 } 5830 } 5831 5832 eb = path->nodes[0]; 5833 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); 5834 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5835 btrfs_set_dev_stats_value(eb, ptr, i, 5836 btrfs_dev_stat_read(device, i)); 5837 btrfs_mark_buffer_dirty(eb); 5838 5839 out: 5840 btrfs_free_path(path); 5841 return ret; 5842 } 5843 5844 /* 5845 * called from commit_transaction. Writes all changed device stats to disk. 5846 */ 5847 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, 5848 struct btrfs_fs_info *fs_info) 5849 { 5850 struct btrfs_root *dev_root = fs_info->dev_root; 5851 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5852 struct btrfs_device *device; 5853 int ret = 0; 5854 5855 mutex_lock(&fs_devices->device_list_mutex); 5856 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5857 if (!device->dev_stats_valid || !device->dev_stats_dirty) 5858 continue; 5859 5860 ret = update_dev_stat_item(trans, dev_root, device); 5861 if (!ret) 5862 device->dev_stats_dirty = 0; 5863 } 5864 mutex_unlock(&fs_devices->device_list_mutex); 5865 5866 return ret; 5867 } 5868 5869 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) 5870 { 5871 btrfs_dev_stat_inc(dev, index); 5872 btrfs_dev_stat_print_on_error(dev); 5873 } 5874 5875 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev) 5876 { 5877 if (!dev->dev_stats_valid) 5878 return; 5879 printk_ratelimited_in_rcu(KERN_ERR 5880 "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5881 rcu_str_deref(dev->name), 5882 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5883 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5884 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5885 btrfs_dev_stat_read(dev, 5886 BTRFS_DEV_STAT_CORRUPTION_ERRS), 5887 btrfs_dev_stat_read(dev, 5888 BTRFS_DEV_STAT_GENERATION_ERRS)); 5889 } 5890 5891 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) 5892 { 5893 int i; 5894 5895 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5896 if (btrfs_dev_stat_read(dev, i) != 0) 5897 break; 5898 if (i == BTRFS_DEV_STAT_VALUES_MAX) 5899 return; /* all values == 0, suppress message */ 5900 5901 printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5902 rcu_str_deref(dev->name), 5903 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5904 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5905 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5906 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), 5907 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); 5908 } 5909 5910 int btrfs_get_dev_stats(struct btrfs_root *root, 5911 struct btrfs_ioctl_get_dev_stats *stats) 5912 { 5913 struct btrfs_device *dev; 5914 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5915 int i; 5916 5917 mutex_lock(&fs_devices->device_list_mutex); 5918 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL); 5919 mutex_unlock(&fs_devices->device_list_mutex); 5920 5921 if (!dev) { 5922 printk(KERN_WARNING 5923 "btrfs: get dev_stats failed, device not found\n"); 5924 return -ENODEV; 5925 } else if (!dev->dev_stats_valid) { 5926 printk(KERN_WARNING 5927 "btrfs: get dev_stats failed, not yet valid\n"); 5928 return -ENODEV; 5929 } else if (stats->flags & BTRFS_DEV_STATS_RESET) { 5930 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5931 if (stats->nr_items > i) 5932 stats->values[i] = 5933 btrfs_dev_stat_read_and_reset(dev, i); 5934 else 5935 btrfs_dev_stat_reset(dev, i); 5936 } 5937 } else { 5938 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5939 if (stats->nr_items > i) 5940 stats->values[i] = btrfs_dev_stat_read(dev, i); 5941 } 5942 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) 5943 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; 5944 return 0; 5945 } 5946 5947 int btrfs_scratch_superblock(struct btrfs_device *device) 5948 { 5949 struct buffer_head *bh; 5950 struct btrfs_super_block *disk_super; 5951 5952 bh = btrfs_read_dev_super(device->bdev); 5953 if (!bh) 5954 return -EINVAL; 5955 disk_super = (struct btrfs_super_block *)bh->b_data; 5956 5957 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 5958 set_buffer_dirty(bh); 5959 sync_dirty_buffer(bh); 5960 brelse(bh); 5961 5962 return 0; 5963 } 5964