1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 #include <linux/sched.h> 19 #include <linux/bio.h> 20 #include <linux/slab.h> 21 #include <linux/buffer_head.h> 22 #include <linux/blkdev.h> 23 #include <linux/random.h> 24 #include <linux/iocontext.h> 25 #include <linux/capability.h> 26 #include <linux/ratelimit.h> 27 #include <linux/kthread.h> 28 #include "compat.h" 29 #include "ctree.h" 30 #include "extent_map.h" 31 #include "disk-io.h" 32 #include "transaction.h" 33 #include "print-tree.h" 34 #include "volumes.h" 35 #include "async-thread.h" 36 #include "check-integrity.h" 37 #include "rcu-string.h" 38 #include "math.h" 39 #include "dev-replace.h" 40 41 static int init_first_rw_device(struct btrfs_trans_handle *trans, 42 struct btrfs_root *root, 43 struct btrfs_device *device); 44 static int btrfs_relocate_sys_chunks(struct btrfs_root *root); 45 static void __btrfs_reset_dev_stats(struct btrfs_device *dev); 46 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); 47 48 static DEFINE_MUTEX(uuid_mutex); 49 static LIST_HEAD(fs_uuids); 50 51 static void lock_chunks(struct btrfs_root *root) 52 { 53 mutex_lock(&root->fs_info->chunk_mutex); 54 } 55 56 static void unlock_chunks(struct btrfs_root *root) 57 { 58 mutex_unlock(&root->fs_info->chunk_mutex); 59 } 60 61 static void free_fs_devices(struct btrfs_fs_devices *fs_devices) 62 { 63 struct btrfs_device *device; 64 WARN_ON(fs_devices->opened); 65 while (!list_empty(&fs_devices->devices)) { 66 device = list_entry(fs_devices->devices.next, 67 struct btrfs_device, dev_list); 68 list_del(&device->dev_list); 69 rcu_string_free(device->name); 70 kfree(device); 71 } 72 kfree(fs_devices); 73 } 74 75 static void btrfs_kobject_uevent(struct block_device *bdev, 76 enum kobject_action action) 77 { 78 int ret; 79 80 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 81 if (ret) 82 pr_warn("Sending event '%d' to kobject: '%s' (%p): failed\n", 83 action, 84 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 85 &disk_to_dev(bdev->bd_disk)->kobj); 86 } 87 88 void btrfs_cleanup_fs_uuids(void) 89 { 90 struct btrfs_fs_devices *fs_devices; 91 92 while (!list_empty(&fs_uuids)) { 93 fs_devices = list_entry(fs_uuids.next, 94 struct btrfs_fs_devices, list); 95 list_del(&fs_devices->list); 96 free_fs_devices(fs_devices); 97 } 98 } 99 100 static noinline struct btrfs_device *__find_device(struct list_head *head, 101 u64 devid, u8 *uuid) 102 { 103 struct btrfs_device *dev; 104 105 list_for_each_entry(dev, head, dev_list) { 106 if (dev->devid == devid && 107 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { 108 return dev; 109 } 110 } 111 return NULL; 112 } 113 114 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid) 115 { 116 struct btrfs_fs_devices *fs_devices; 117 118 list_for_each_entry(fs_devices, &fs_uuids, list) { 119 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) 120 return fs_devices; 121 } 122 return NULL; 123 } 124 125 static int 126 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder, 127 int flush, struct block_device **bdev, 128 struct buffer_head **bh) 129 { 130 int ret; 131 132 *bdev = blkdev_get_by_path(device_path, flags, holder); 133 134 if (IS_ERR(*bdev)) { 135 ret = PTR_ERR(*bdev); 136 printk(KERN_INFO "btrfs: open %s failed\n", device_path); 137 goto error; 138 } 139 140 if (flush) 141 filemap_write_and_wait((*bdev)->bd_inode->i_mapping); 142 ret = set_blocksize(*bdev, 4096); 143 if (ret) { 144 blkdev_put(*bdev, flags); 145 goto error; 146 } 147 invalidate_bdev(*bdev); 148 *bh = btrfs_read_dev_super(*bdev); 149 if (!*bh) { 150 ret = -EINVAL; 151 blkdev_put(*bdev, flags); 152 goto error; 153 } 154 155 return 0; 156 157 error: 158 *bdev = NULL; 159 *bh = NULL; 160 return ret; 161 } 162 163 static void requeue_list(struct btrfs_pending_bios *pending_bios, 164 struct bio *head, struct bio *tail) 165 { 166 167 struct bio *old_head; 168 169 old_head = pending_bios->head; 170 pending_bios->head = head; 171 if (pending_bios->tail) 172 tail->bi_next = old_head; 173 else 174 pending_bios->tail = tail; 175 } 176 177 /* 178 * we try to collect pending bios for a device so we don't get a large 179 * number of procs sending bios down to the same device. This greatly 180 * improves the schedulers ability to collect and merge the bios. 181 * 182 * But, it also turns into a long list of bios to process and that is sure 183 * to eventually make the worker thread block. The solution here is to 184 * make some progress and then put this work struct back at the end of 185 * the list if the block device is congested. This way, multiple devices 186 * can make progress from a single worker thread. 187 */ 188 static noinline void run_scheduled_bios(struct btrfs_device *device) 189 { 190 struct bio *pending; 191 struct backing_dev_info *bdi; 192 struct btrfs_fs_info *fs_info; 193 struct btrfs_pending_bios *pending_bios; 194 struct bio *tail; 195 struct bio *cur; 196 int again = 0; 197 unsigned long num_run; 198 unsigned long batch_run = 0; 199 unsigned long limit; 200 unsigned long last_waited = 0; 201 int force_reg = 0; 202 int sync_pending = 0; 203 struct blk_plug plug; 204 205 /* 206 * this function runs all the bios we've collected for 207 * a particular device. We don't want to wander off to 208 * another device without first sending all of these down. 209 * So, setup a plug here and finish it off before we return 210 */ 211 blk_start_plug(&plug); 212 213 bdi = blk_get_backing_dev_info(device->bdev); 214 fs_info = device->dev_root->fs_info; 215 limit = btrfs_async_submit_limit(fs_info); 216 limit = limit * 2 / 3; 217 218 loop: 219 spin_lock(&device->io_lock); 220 221 loop_lock: 222 num_run = 0; 223 224 /* take all the bios off the list at once and process them 225 * later on (without the lock held). But, remember the 226 * tail and other pointers so the bios can be properly reinserted 227 * into the list if we hit congestion 228 */ 229 if (!force_reg && device->pending_sync_bios.head) { 230 pending_bios = &device->pending_sync_bios; 231 force_reg = 1; 232 } else { 233 pending_bios = &device->pending_bios; 234 force_reg = 0; 235 } 236 237 pending = pending_bios->head; 238 tail = pending_bios->tail; 239 WARN_ON(pending && !tail); 240 241 /* 242 * if pending was null this time around, no bios need processing 243 * at all and we can stop. Otherwise it'll loop back up again 244 * and do an additional check so no bios are missed. 245 * 246 * device->running_pending is used to synchronize with the 247 * schedule_bio code. 248 */ 249 if (device->pending_sync_bios.head == NULL && 250 device->pending_bios.head == NULL) { 251 again = 0; 252 device->running_pending = 0; 253 } else { 254 again = 1; 255 device->running_pending = 1; 256 } 257 258 pending_bios->head = NULL; 259 pending_bios->tail = NULL; 260 261 spin_unlock(&device->io_lock); 262 263 while (pending) { 264 265 rmb(); 266 /* we want to work on both lists, but do more bios on the 267 * sync list than the regular list 268 */ 269 if ((num_run > 32 && 270 pending_bios != &device->pending_sync_bios && 271 device->pending_sync_bios.head) || 272 (num_run > 64 && pending_bios == &device->pending_sync_bios && 273 device->pending_bios.head)) { 274 spin_lock(&device->io_lock); 275 requeue_list(pending_bios, pending, tail); 276 goto loop_lock; 277 } 278 279 cur = pending; 280 pending = pending->bi_next; 281 cur->bi_next = NULL; 282 283 if (atomic_dec_return(&fs_info->nr_async_bios) < limit && 284 waitqueue_active(&fs_info->async_submit_wait)) 285 wake_up(&fs_info->async_submit_wait); 286 287 BUG_ON(atomic_read(&cur->bi_cnt) == 0); 288 289 /* 290 * if we're doing the sync list, record that our 291 * plug has some sync requests on it 292 * 293 * If we're doing the regular list and there are 294 * sync requests sitting around, unplug before 295 * we add more 296 */ 297 if (pending_bios == &device->pending_sync_bios) { 298 sync_pending = 1; 299 } else if (sync_pending) { 300 blk_finish_plug(&plug); 301 blk_start_plug(&plug); 302 sync_pending = 0; 303 } 304 305 btrfsic_submit_bio(cur->bi_rw, cur); 306 num_run++; 307 batch_run++; 308 if (need_resched()) 309 cond_resched(); 310 311 /* 312 * we made progress, there is more work to do and the bdi 313 * is now congested. Back off and let other work structs 314 * run instead 315 */ 316 if (pending && bdi_write_congested(bdi) && batch_run > 8 && 317 fs_info->fs_devices->open_devices > 1) { 318 struct io_context *ioc; 319 320 ioc = current->io_context; 321 322 /* 323 * the main goal here is that we don't want to 324 * block if we're going to be able to submit 325 * more requests without blocking. 326 * 327 * This code does two great things, it pokes into 328 * the elevator code from a filesystem _and_ 329 * it makes assumptions about how batching works. 330 */ 331 if (ioc && ioc->nr_batch_requests > 0 && 332 time_before(jiffies, ioc->last_waited + HZ/50UL) && 333 (last_waited == 0 || 334 ioc->last_waited == last_waited)) { 335 /* 336 * we want to go through our batch of 337 * requests and stop. So, we copy out 338 * the ioc->last_waited time and test 339 * against it before looping 340 */ 341 last_waited = ioc->last_waited; 342 if (need_resched()) 343 cond_resched(); 344 continue; 345 } 346 spin_lock(&device->io_lock); 347 requeue_list(pending_bios, pending, tail); 348 device->running_pending = 1; 349 350 spin_unlock(&device->io_lock); 351 btrfs_requeue_work(&device->work); 352 goto done; 353 } 354 /* unplug every 64 requests just for good measure */ 355 if (batch_run % 64 == 0) { 356 blk_finish_plug(&plug); 357 blk_start_plug(&plug); 358 sync_pending = 0; 359 } 360 } 361 362 cond_resched(); 363 if (again) 364 goto loop; 365 366 spin_lock(&device->io_lock); 367 if (device->pending_bios.head || device->pending_sync_bios.head) 368 goto loop_lock; 369 spin_unlock(&device->io_lock); 370 371 done: 372 blk_finish_plug(&plug); 373 } 374 375 static void pending_bios_fn(struct btrfs_work *work) 376 { 377 struct btrfs_device *device; 378 379 device = container_of(work, struct btrfs_device, work); 380 run_scheduled_bios(device); 381 } 382 383 static noinline int device_list_add(const char *path, 384 struct btrfs_super_block *disk_super, 385 u64 devid, struct btrfs_fs_devices **fs_devices_ret) 386 { 387 struct btrfs_device *device; 388 struct btrfs_fs_devices *fs_devices; 389 struct rcu_string *name; 390 u64 found_transid = btrfs_super_generation(disk_super); 391 392 fs_devices = find_fsid(disk_super->fsid); 393 if (!fs_devices) { 394 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 395 if (!fs_devices) 396 return -ENOMEM; 397 INIT_LIST_HEAD(&fs_devices->devices); 398 INIT_LIST_HEAD(&fs_devices->alloc_list); 399 list_add(&fs_devices->list, &fs_uuids); 400 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE); 401 fs_devices->latest_devid = devid; 402 fs_devices->latest_trans = found_transid; 403 mutex_init(&fs_devices->device_list_mutex); 404 device = NULL; 405 } else { 406 device = __find_device(&fs_devices->devices, devid, 407 disk_super->dev_item.uuid); 408 } 409 if (!device) { 410 if (fs_devices->opened) 411 return -EBUSY; 412 413 device = kzalloc(sizeof(*device), GFP_NOFS); 414 if (!device) { 415 /* we can safely leave the fs_devices entry around */ 416 return -ENOMEM; 417 } 418 device->devid = devid; 419 device->dev_stats_valid = 0; 420 device->work.func = pending_bios_fn; 421 memcpy(device->uuid, disk_super->dev_item.uuid, 422 BTRFS_UUID_SIZE); 423 spin_lock_init(&device->io_lock); 424 425 name = rcu_string_strdup(path, GFP_NOFS); 426 if (!name) { 427 kfree(device); 428 return -ENOMEM; 429 } 430 rcu_assign_pointer(device->name, name); 431 INIT_LIST_HEAD(&device->dev_alloc_list); 432 433 /* init readahead state */ 434 spin_lock_init(&device->reada_lock); 435 device->reada_curr_zone = NULL; 436 atomic_set(&device->reada_in_flight, 0); 437 device->reada_next = 0; 438 INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT); 439 INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT); 440 441 mutex_lock(&fs_devices->device_list_mutex); 442 list_add_rcu(&device->dev_list, &fs_devices->devices); 443 mutex_unlock(&fs_devices->device_list_mutex); 444 445 device->fs_devices = fs_devices; 446 fs_devices->num_devices++; 447 } else if (!device->name || strcmp(device->name->str, path)) { 448 name = rcu_string_strdup(path, GFP_NOFS); 449 if (!name) 450 return -ENOMEM; 451 rcu_string_free(device->name); 452 rcu_assign_pointer(device->name, name); 453 if (device->missing) { 454 fs_devices->missing_devices--; 455 device->missing = 0; 456 } 457 } 458 459 if (found_transid > fs_devices->latest_trans) { 460 fs_devices->latest_devid = devid; 461 fs_devices->latest_trans = found_transid; 462 } 463 *fs_devices_ret = fs_devices; 464 return 0; 465 } 466 467 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) 468 { 469 struct btrfs_fs_devices *fs_devices; 470 struct btrfs_device *device; 471 struct btrfs_device *orig_dev; 472 473 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 474 if (!fs_devices) 475 return ERR_PTR(-ENOMEM); 476 477 INIT_LIST_HEAD(&fs_devices->devices); 478 INIT_LIST_HEAD(&fs_devices->alloc_list); 479 INIT_LIST_HEAD(&fs_devices->list); 480 mutex_init(&fs_devices->device_list_mutex); 481 fs_devices->latest_devid = orig->latest_devid; 482 fs_devices->latest_trans = orig->latest_trans; 483 fs_devices->total_devices = orig->total_devices; 484 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid)); 485 486 /* We have held the volume lock, it is safe to get the devices. */ 487 list_for_each_entry(orig_dev, &orig->devices, dev_list) { 488 struct rcu_string *name; 489 490 device = kzalloc(sizeof(*device), GFP_NOFS); 491 if (!device) 492 goto error; 493 494 /* 495 * This is ok to do without rcu read locked because we hold the 496 * uuid mutex so nothing we touch in here is going to disappear. 497 */ 498 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS); 499 if (!name) { 500 kfree(device); 501 goto error; 502 } 503 rcu_assign_pointer(device->name, name); 504 505 device->devid = orig_dev->devid; 506 device->work.func = pending_bios_fn; 507 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid)); 508 spin_lock_init(&device->io_lock); 509 INIT_LIST_HEAD(&device->dev_list); 510 INIT_LIST_HEAD(&device->dev_alloc_list); 511 512 list_add(&device->dev_list, &fs_devices->devices); 513 device->fs_devices = fs_devices; 514 fs_devices->num_devices++; 515 } 516 return fs_devices; 517 error: 518 free_fs_devices(fs_devices); 519 return ERR_PTR(-ENOMEM); 520 } 521 522 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info, 523 struct btrfs_fs_devices *fs_devices, int step) 524 { 525 struct btrfs_device *device, *next; 526 527 struct block_device *latest_bdev = NULL; 528 u64 latest_devid = 0; 529 u64 latest_transid = 0; 530 531 mutex_lock(&uuid_mutex); 532 again: 533 /* This is the initialized path, it is safe to release the devices. */ 534 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 535 if (device->in_fs_metadata) { 536 if (!device->is_tgtdev_for_dev_replace && 537 (!latest_transid || 538 device->generation > latest_transid)) { 539 latest_devid = device->devid; 540 latest_transid = device->generation; 541 latest_bdev = device->bdev; 542 } 543 continue; 544 } 545 546 if (device->devid == BTRFS_DEV_REPLACE_DEVID) { 547 /* 548 * In the first step, keep the device which has 549 * the correct fsid and the devid that is used 550 * for the dev_replace procedure. 551 * In the second step, the dev_replace state is 552 * read from the device tree and it is known 553 * whether the procedure is really active or 554 * not, which means whether this device is 555 * used or whether it should be removed. 556 */ 557 if (step == 0 || device->is_tgtdev_for_dev_replace) { 558 continue; 559 } 560 } 561 if (device->bdev) { 562 blkdev_put(device->bdev, device->mode); 563 device->bdev = NULL; 564 fs_devices->open_devices--; 565 } 566 if (device->writeable) { 567 list_del_init(&device->dev_alloc_list); 568 device->writeable = 0; 569 if (!device->is_tgtdev_for_dev_replace) 570 fs_devices->rw_devices--; 571 } 572 list_del_init(&device->dev_list); 573 fs_devices->num_devices--; 574 rcu_string_free(device->name); 575 kfree(device); 576 } 577 578 if (fs_devices->seed) { 579 fs_devices = fs_devices->seed; 580 goto again; 581 } 582 583 fs_devices->latest_bdev = latest_bdev; 584 fs_devices->latest_devid = latest_devid; 585 fs_devices->latest_trans = latest_transid; 586 587 mutex_unlock(&uuid_mutex); 588 } 589 590 static void __free_device(struct work_struct *work) 591 { 592 struct btrfs_device *device; 593 594 device = container_of(work, struct btrfs_device, rcu_work); 595 596 if (device->bdev) 597 blkdev_put(device->bdev, device->mode); 598 599 rcu_string_free(device->name); 600 kfree(device); 601 } 602 603 static void free_device(struct rcu_head *head) 604 { 605 struct btrfs_device *device; 606 607 device = container_of(head, struct btrfs_device, rcu); 608 609 INIT_WORK(&device->rcu_work, __free_device); 610 schedule_work(&device->rcu_work); 611 } 612 613 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 614 { 615 struct btrfs_device *device; 616 617 if (--fs_devices->opened > 0) 618 return 0; 619 620 mutex_lock(&fs_devices->device_list_mutex); 621 list_for_each_entry(device, &fs_devices->devices, dev_list) { 622 struct btrfs_device *new_device; 623 struct rcu_string *name; 624 625 if (device->bdev) 626 fs_devices->open_devices--; 627 628 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 629 list_del_init(&device->dev_alloc_list); 630 fs_devices->rw_devices--; 631 } 632 633 if (device->can_discard) 634 fs_devices->num_can_discard--; 635 636 new_device = kmalloc(sizeof(*new_device), GFP_NOFS); 637 BUG_ON(!new_device); /* -ENOMEM */ 638 memcpy(new_device, device, sizeof(*new_device)); 639 640 /* Safe because we are under uuid_mutex */ 641 if (device->name) { 642 name = rcu_string_strdup(device->name->str, GFP_NOFS); 643 BUG_ON(device->name && !name); /* -ENOMEM */ 644 rcu_assign_pointer(new_device->name, name); 645 } 646 new_device->bdev = NULL; 647 new_device->writeable = 0; 648 new_device->in_fs_metadata = 0; 649 new_device->can_discard = 0; 650 list_replace_rcu(&device->dev_list, &new_device->dev_list); 651 652 call_rcu(&device->rcu, free_device); 653 } 654 mutex_unlock(&fs_devices->device_list_mutex); 655 656 WARN_ON(fs_devices->open_devices); 657 WARN_ON(fs_devices->rw_devices); 658 fs_devices->opened = 0; 659 fs_devices->seeding = 0; 660 661 return 0; 662 } 663 664 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 665 { 666 struct btrfs_fs_devices *seed_devices = NULL; 667 int ret; 668 669 mutex_lock(&uuid_mutex); 670 ret = __btrfs_close_devices(fs_devices); 671 if (!fs_devices->opened) { 672 seed_devices = fs_devices->seed; 673 fs_devices->seed = NULL; 674 } 675 mutex_unlock(&uuid_mutex); 676 677 while (seed_devices) { 678 fs_devices = seed_devices; 679 seed_devices = fs_devices->seed; 680 __btrfs_close_devices(fs_devices); 681 free_fs_devices(fs_devices); 682 } 683 return ret; 684 } 685 686 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 687 fmode_t flags, void *holder) 688 { 689 struct request_queue *q; 690 struct block_device *bdev; 691 struct list_head *head = &fs_devices->devices; 692 struct btrfs_device *device; 693 struct block_device *latest_bdev = NULL; 694 struct buffer_head *bh; 695 struct btrfs_super_block *disk_super; 696 u64 latest_devid = 0; 697 u64 latest_transid = 0; 698 u64 devid; 699 int seeding = 1; 700 int ret = 0; 701 702 flags |= FMODE_EXCL; 703 704 list_for_each_entry(device, head, dev_list) { 705 if (device->bdev) 706 continue; 707 if (!device->name) 708 continue; 709 710 ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, 711 &bdev, &bh); 712 if (ret) 713 continue; 714 715 disk_super = (struct btrfs_super_block *)bh->b_data; 716 devid = btrfs_stack_device_id(&disk_super->dev_item); 717 if (devid != device->devid) 718 goto error_brelse; 719 720 if (memcmp(device->uuid, disk_super->dev_item.uuid, 721 BTRFS_UUID_SIZE)) 722 goto error_brelse; 723 724 device->generation = btrfs_super_generation(disk_super); 725 if (!latest_transid || device->generation > latest_transid) { 726 latest_devid = devid; 727 latest_transid = device->generation; 728 latest_bdev = bdev; 729 } 730 731 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { 732 device->writeable = 0; 733 } else { 734 device->writeable = !bdev_read_only(bdev); 735 seeding = 0; 736 } 737 738 q = bdev_get_queue(bdev); 739 if (blk_queue_discard(q)) { 740 device->can_discard = 1; 741 fs_devices->num_can_discard++; 742 } 743 744 device->bdev = bdev; 745 device->in_fs_metadata = 0; 746 device->mode = flags; 747 748 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 749 fs_devices->rotating = 1; 750 751 fs_devices->open_devices++; 752 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 753 fs_devices->rw_devices++; 754 list_add(&device->dev_alloc_list, 755 &fs_devices->alloc_list); 756 } 757 brelse(bh); 758 continue; 759 760 error_brelse: 761 brelse(bh); 762 blkdev_put(bdev, flags); 763 continue; 764 } 765 if (fs_devices->open_devices == 0) { 766 ret = -EINVAL; 767 goto out; 768 } 769 fs_devices->seeding = seeding; 770 fs_devices->opened = 1; 771 fs_devices->latest_bdev = latest_bdev; 772 fs_devices->latest_devid = latest_devid; 773 fs_devices->latest_trans = latest_transid; 774 fs_devices->total_rw_bytes = 0; 775 out: 776 return ret; 777 } 778 779 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 780 fmode_t flags, void *holder) 781 { 782 int ret; 783 784 mutex_lock(&uuid_mutex); 785 if (fs_devices->opened) { 786 fs_devices->opened++; 787 ret = 0; 788 } else { 789 ret = __btrfs_open_devices(fs_devices, flags, holder); 790 } 791 mutex_unlock(&uuid_mutex); 792 return ret; 793 } 794 795 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, 796 struct btrfs_fs_devices **fs_devices_ret) 797 { 798 struct btrfs_super_block *disk_super; 799 struct block_device *bdev; 800 struct buffer_head *bh; 801 int ret; 802 u64 devid; 803 u64 transid; 804 u64 total_devices; 805 806 flags |= FMODE_EXCL; 807 mutex_lock(&uuid_mutex); 808 ret = btrfs_get_bdev_and_sb(path, flags, holder, 0, &bdev, &bh); 809 if (ret) 810 goto error; 811 disk_super = (struct btrfs_super_block *)bh->b_data; 812 devid = btrfs_stack_device_id(&disk_super->dev_item); 813 transid = btrfs_super_generation(disk_super); 814 total_devices = btrfs_super_num_devices(disk_super); 815 if (disk_super->label[0]) { 816 if (disk_super->label[BTRFS_LABEL_SIZE - 1]) 817 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0'; 818 printk(KERN_INFO "device label %s ", disk_super->label); 819 } else { 820 printk(KERN_INFO "device fsid %pU ", disk_super->fsid); 821 } 822 printk(KERN_CONT "devid %llu transid %llu %s\n", 823 (unsigned long long)devid, (unsigned long long)transid, path); 824 ret = device_list_add(path, disk_super, devid, fs_devices_ret); 825 if (!ret && fs_devices_ret) 826 (*fs_devices_ret)->total_devices = total_devices; 827 brelse(bh); 828 blkdev_put(bdev, flags); 829 error: 830 mutex_unlock(&uuid_mutex); 831 return ret; 832 } 833 834 /* helper to account the used device space in the range */ 835 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, 836 u64 end, u64 *length) 837 { 838 struct btrfs_key key; 839 struct btrfs_root *root = device->dev_root; 840 struct btrfs_dev_extent *dev_extent; 841 struct btrfs_path *path; 842 u64 extent_end; 843 int ret; 844 int slot; 845 struct extent_buffer *l; 846 847 *length = 0; 848 849 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace) 850 return 0; 851 852 path = btrfs_alloc_path(); 853 if (!path) 854 return -ENOMEM; 855 path->reada = 2; 856 857 key.objectid = device->devid; 858 key.offset = start; 859 key.type = BTRFS_DEV_EXTENT_KEY; 860 861 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 862 if (ret < 0) 863 goto out; 864 if (ret > 0) { 865 ret = btrfs_previous_item(root, path, key.objectid, key.type); 866 if (ret < 0) 867 goto out; 868 } 869 870 while (1) { 871 l = path->nodes[0]; 872 slot = path->slots[0]; 873 if (slot >= btrfs_header_nritems(l)) { 874 ret = btrfs_next_leaf(root, path); 875 if (ret == 0) 876 continue; 877 if (ret < 0) 878 goto out; 879 880 break; 881 } 882 btrfs_item_key_to_cpu(l, &key, slot); 883 884 if (key.objectid < device->devid) 885 goto next; 886 887 if (key.objectid > device->devid) 888 break; 889 890 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 891 goto next; 892 893 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 894 extent_end = key.offset + btrfs_dev_extent_length(l, 895 dev_extent); 896 if (key.offset <= start && extent_end > end) { 897 *length = end - start + 1; 898 break; 899 } else if (key.offset <= start && extent_end > start) 900 *length += extent_end - start; 901 else if (key.offset > start && extent_end <= end) 902 *length += extent_end - key.offset; 903 else if (key.offset > start && key.offset <= end) { 904 *length += end - key.offset + 1; 905 break; 906 } else if (key.offset > end) 907 break; 908 909 next: 910 path->slots[0]++; 911 } 912 ret = 0; 913 out: 914 btrfs_free_path(path); 915 return ret; 916 } 917 918 /* 919 * find_free_dev_extent - find free space in the specified device 920 * @device: the device which we search the free space in 921 * @num_bytes: the size of the free space that we need 922 * @start: store the start of the free space. 923 * @len: the size of the free space. that we find, or the size of the max 924 * free space if we don't find suitable free space 925 * 926 * this uses a pretty simple search, the expectation is that it is 927 * called very infrequently and that a given device has a small number 928 * of extents 929 * 930 * @start is used to store the start of the free space if we find. But if we 931 * don't find suitable free space, it will be used to store the start position 932 * of the max free space. 933 * 934 * @len is used to store the size of the free space that we find. 935 * But if we don't find suitable free space, it is used to store the size of 936 * the max free space. 937 */ 938 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes, 939 u64 *start, u64 *len) 940 { 941 struct btrfs_key key; 942 struct btrfs_root *root = device->dev_root; 943 struct btrfs_dev_extent *dev_extent; 944 struct btrfs_path *path; 945 u64 hole_size; 946 u64 max_hole_start; 947 u64 max_hole_size; 948 u64 extent_end; 949 u64 search_start; 950 u64 search_end = device->total_bytes; 951 int ret; 952 int slot; 953 struct extent_buffer *l; 954 955 /* FIXME use last free of some kind */ 956 957 /* we don't want to overwrite the superblock on the drive, 958 * so we make sure to start at an offset of at least 1MB 959 */ 960 search_start = max(root->fs_info->alloc_start, 1024ull * 1024); 961 962 max_hole_start = search_start; 963 max_hole_size = 0; 964 hole_size = 0; 965 966 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) { 967 ret = -ENOSPC; 968 goto error; 969 } 970 971 path = btrfs_alloc_path(); 972 if (!path) { 973 ret = -ENOMEM; 974 goto error; 975 } 976 path->reada = 2; 977 978 key.objectid = device->devid; 979 key.offset = search_start; 980 key.type = BTRFS_DEV_EXTENT_KEY; 981 982 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 983 if (ret < 0) 984 goto out; 985 if (ret > 0) { 986 ret = btrfs_previous_item(root, path, key.objectid, key.type); 987 if (ret < 0) 988 goto out; 989 } 990 991 while (1) { 992 l = path->nodes[0]; 993 slot = path->slots[0]; 994 if (slot >= btrfs_header_nritems(l)) { 995 ret = btrfs_next_leaf(root, path); 996 if (ret == 0) 997 continue; 998 if (ret < 0) 999 goto out; 1000 1001 break; 1002 } 1003 btrfs_item_key_to_cpu(l, &key, slot); 1004 1005 if (key.objectid < device->devid) 1006 goto next; 1007 1008 if (key.objectid > device->devid) 1009 break; 1010 1011 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 1012 goto next; 1013 1014 if (key.offset > search_start) { 1015 hole_size = key.offset - search_start; 1016 1017 if (hole_size > max_hole_size) { 1018 max_hole_start = search_start; 1019 max_hole_size = hole_size; 1020 } 1021 1022 /* 1023 * If this free space is greater than which we need, 1024 * it must be the max free space that we have found 1025 * until now, so max_hole_start must point to the start 1026 * of this free space and the length of this free space 1027 * is stored in max_hole_size. Thus, we return 1028 * max_hole_start and max_hole_size and go back to the 1029 * caller. 1030 */ 1031 if (hole_size >= num_bytes) { 1032 ret = 0; 1033 goto out; 1034 } 1035 } 1036 1037 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 1038 extent_end = key.offset + btrfs_dev_extent_length(l, 1039 dev_extent); 1040 if (extent_end > search_start) 1041 search_start = extent_end; 1042 next: 1043 path->slots[0]++; 1044 cond_resched(); 1045 } 1046 1047 /* 1048 * At this point, search_start should be the end of 1049 * allocated dev extents, and when shrinking the device, 1050 * search_end may be smaller than search_start. 1051 */ 1052 if (search_end > search_start) 1053 hole_size = search_end - search_start; 1054 1055 if (hole_size > max_hole_size) { 1056 max_hole_start = search_start; 1057 max_hole_size = hole_size; 1058 } 1059 1060 /* See above. */ 1061 if (hole_size < num_bytes) 1062 ret = -ENOSPC; 1063 else 1064 ret = 0; 1065 1066 out: 1067 btrfs_free_path(path); 1068 error: 1069 *start = max_hole_start; 1070 if (len) 1071 *len = max_hole_size; 1072 return ret; 1073 } 1074 1075 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, 1076 struct btrfs_device *device, 1077 u64 start) 1078 { 1079 int ret; 1080 struct btrfs_path *path; 1081 struct btrfs_root *root = device->dev_root; 1082 struct btrfs_key key; 1083 struct btrfs_key found_key; 1084 struct extent_buffer *leaf = NULL; 1085 struct btrfs_dev_extent *extent = NULL; 1086 1087 path = btrfs_alloc_path(); 1088 if (!path) 1089 return -ENOMEM; 1090 1091 key.objectid = device->devid; 1092 key.offset = start; 1093 key.type = BTRFS_DEV_EXTENT_KEY; 1094 again: 1095 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1096 if (ret > 0) { 1097 ret = btrfs_previous_item(root, path, key.objectid, 1098 BTRFS_DEV_EXTENT_KEY); 1099 if (ret) 1100 goto out; 1101 leaf = path->nodes[0]; 1102 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1103 extent = btrfs_item_ptr(leaf, path->slots[0], 1104 struct btrfs_dev_extent); 1105 BUG_ON(found_key.offset > start || found_key.offset + 1106 btrfs_dev_extent_length(leaf, extent) < start); 1107 key = found_key; 1108 btrfs_release_path(path); 1109 goto again; 1110 } else if (ret == 0) { 1111 leaf = path->nodes[0]; 1112 extent = btrfs_item_ptr(leaf, path->slots[0], 1113 struct btrfs_dev_extent); 1114 } else { 1115 btrfs_error(root->fs_info, ret, "Slot search failed"); 1116 goto out; 1117 } 1118 1119 if (device->bytes_used > 0) { 1120 u64 len = btrfs_dev_extent_length(leaf, extent); 1121 device->bytes_used -= len; 1122 spin_lock(&root->fs_info->free_chunk_lock); 1123 root->fs_info->free_chunk_space += len; 1124 spin_unlock(&root->fs_info->free_chunk_lock); 1125 } 1126 ret = btrfs_del_item(trans, root, path); 1127 if (ret) { 1128 btrfs_error(root->fs_info, ret, 1129 "Failed to remove dev extent item"); 1130 } 1131 out: 1132 btrfs_free_path(path); 1133 return ret; 1134 } 1135 1136 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, 1137 struct btrfs_device *device, 1138 u64 chunk_tree, u64 chunk_objectid, 1139 u64 chunk_offset, u64 start, u64 num_bytes) 1140 { 1141 int ret; 1142 struct btrfs_path *path; 1143 struct btrfs_root *root = device->dev_root; 1144 struct btrfs_dev_extent *extent; 1145 struct extent_buffer *leaf; 1146 struct btrfs_key key; 1147 1148 WARN_ON(!device->in_fs_metadata); 1149 WARN_ON(device->is_tgtdev_for_dev_replace); 1150 path = btrfs_alloc_path(); 1151 if (!path) 1152 return -ENOMEM; 1153 1154 key.objectid = device->devid; 1155 key.offset = start; 1156 key.type = BTRFS_DEV_EXTENT_KEY; 1157 ret = btrfs_insert_empty_item(trans, root, path, &key, 1158 sizeof(*extent)); 1159 if (ret) 1160 goto out; 1161 1162 leaf = path->nodes[0]; 1163 extent = btrfs_item_ptr(leaf, path->slots[0], 1164 struct btrfs_dev_extent); 1165 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree); 1166 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid); 1167 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); 1168 1169 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 1170 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent), 1171 BTRFS_UUID_SIZE); 1172 1173 btrfs_set_dev_extent_length(leaf, extent, num_bytes); 1174 btrfs_mark_buffer_dirty(leaf); 1175 out: 1176 btrfs_free_path(path); 1177 return ret; 1178 } 1179 1180 static noinline int find_next_chunk(struct btrfs_root *root, 1181 u64 objectid, u64 *offset) 1182 { 1183 struct btrfs_path *path; 1184 int ret; 1185 struct btrfs_key key; 1186 struct btrfs_chunk *chunk; 1187 struct btrfs_key found_key; 1188 1189 path = btrfs_alloc_path(); 1190 if (!path) 1191 return -ENOMEM; 1192 1193 key.objectid = objectid; 1194 key.offset = (u64)-1; 1195 key.type = BTRFS_CHUNK_ITEM_KEY; 1196 1197 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1198 if (ret < 0) 1199 goto error; 1200 1201 BUG_ON(ret == 0); /* Corruption */ 1202 1203 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY); 1204 if (ret) { 1205 *offset = 0; 1206 } else { 1207 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1208 path->slots[0]); 1209 if (found_key.objectid != objectid) 1210 *offset = 0; 1211 else { 1212 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], 1213 struct btrfs_chunk); 1214 *offset = found_key.offset + 1215 btrfs_chunk_length(path->nodes[0], chunk); 1216 } 1217 } 1218 ret = 0; 1219 error: 1220 btrfs_free_path(path); 1221 return ret; 1222 } 1223 1224 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid) 1225 { 1226 int ret; 1227 struct btrfs_key key; 1228 struct btrfs_key found_key; 1229 struct btrfs_path *path; 1230 1231 root = root->fs_info->chunk_root; 1232 1233 path = btrfs_alloc_path(); 1234 if (!path) 1235 return -ENOMEM; 1236 1237 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1238 key.type = BTRFS_DEV_ITEM_KEY; 1239 key.offset = (u64)-1; 1240 1241 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1242 if (ret < 0) 1243 goto error; 1244 1245 BUG_ON(ret == 0); /* Corruption */ 1246 1247 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID, 1248 BTRFS_DEV_ITEM_KEY); 1249 if (ret) { 1250 *objectid = 1; 1251 } else { 1252 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1253 path->slots[0]); 1254 *objectid = found_key.offset + 1; 1255 } 1256 ret = 0; 1257 error: 1258 btrfs_free_path(path); 1259 return ret; 1260 } 1261 1262 /* 1263 * the device information is stored in the chunk root 1264 * the btrfs_device struct should be fully filled in 1265 */ 1266 int btrfs_add_device(struct btrfs_trans_handle *trans, 1267 struct btrfs_root *root, 1268 struct btrfs_device *device) 1269 { 1270 int ret; 1271 struct btrfs_path *path; 1272 struct btrfs_dev_item *dev_item; 1273 struct extent_buffer *leaf; 1274 struct btrfs_key key; 1275 unsigned long ptr; 1276 1277 root = root->fs_info->chunk_root; 1278 1279 path = btrfs_alloc_path(); 1280 if (!path) 1281 return -ENOMEM; 1282 1283 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1284 key.type = BTRFS_DEV_ITEM_KEY; 1285 key.offset = device->devid; 1286 1287 ret = btrfs_insert_empty_item(trans, root, path, &key, 1288 sizeof(*dev_item)); 1289 if (ret) 1290 goto out; 1291 1292 leaf = path->nodes[0]; 1293 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 1294 1295 btrfs_set_device_id(leaf, dev_item, device->devid); 1296 btrfs_set_device_generation(leaf, dev_item, 0); 1297 btrfs_set_device_type(leaf, dev_item, device->type); 1298 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 1299 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 1300 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 1301 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); 1302 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 1303 btrfs_set_device_group(leaf, dev_item, 0); 1304 btrfs_set_device_seek_speed(leaf, dev_item, 0); 1305 btrfs_set_device_bandwidth(leaf, dev_item, 0); 1306 btrfs_set_device_start_offset(leaf, dev_item, 0); 1307 1308 ptr = (unsigned long)btrfs_device_uuid(dev_item); 1309 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 1310 ptr = (unsigned long)btrfs_device_fsid(dev_item); 1311 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE); 1312 btrfs_mark_buffer_dirty(leaf); 1313 1314 ret = 0; 1315 out: 1316 btrfs_free_path(path); 1317 return ret; 1318 } 1319 1320 static int btrfs_rm_dev_item(struct btrfs_root *root, 1321 struct btrfs_device *device) 1322 { 1323 int ret; 1324 struct btrfs_path *path; 1325 struct btrfs_key key; 1326 struct btrfs_trans_handle *trans; 1327 1328 root = root->fs_info->chunk_root; 1329 1330 path = btrfs_alloc_path(); 1331 if (!path) 1332 return -ENOMEM; 1333 1334 trans = btrfs_start_transaction(root, 0); 1335 if (IS_ERR(trans)) { 1336 btrfs_free_path(path); 1337 return PTR_ERR(trans); 1338 } 1339 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1340 key.type = BTRFS_DEV_ITEM_KEY; 1341 key.offset = device->devid; 1342 lock_chunks(root); 1343 1344 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1345 if (ret < 0) 1346 goto out; 1347 1348 if (ret > 0) { 1349 ret = -ENOENT; 1350 goto out; 1351 } 1352 1353 ret = btrfs_del_item(trans, root, path); 1354 if (ret) 1355 goto out; 1356 out: 1357 btrfs_free_path(path); 1358 unlock_chunks(root); 1359 btrfs_commit_transaction(trans, root); 1360 return ret; 1361 } 1362 1363 int btrfs_rm_device(struct btrfs_root *root, char *device_path) 1364 { 1365 struct btrfs_device *device; 1366 struct btrfs_device *next_device; 1367 struct block_device *bdev; 1368 struct buffer_head *bh = NULL; 1369 struct btrfs_super_block *disk_super; 1370 struct btrfs_fs_devices *cur_devices; 1371 u64 all_avail; 1372 u64 devid; 1373 u64 num_devices; 1374 u8 *dev_uuid; 1375 int ret = 0; 1376 bool clear_super = false; 1377 1378 mutex_lock(&uuid_mutex); 1379 1380 all_avail = root->fs_info->avail_data_alloc_bits | 1381 root->fs_info->avail_system_alloc_bits | 1382 root->fs_info->avail_metadata_alloc_bits; 1383 1384 num_devices = root->fs_info->fs_devices->num_devices; 1385 btrfs_dev_replace_lock(&root->fs_info->dev_replace); 1386 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) { 1387 WARN_ON(num_devices < 1); 1388 num_devices--; 1389 } 1390 btrfs_dev_replace_unlock(&root->fs_info->dev_replace); 1391 1392 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) { 1393 printk(KERN_ERR "btrfs: unable to go below four devices " 1394 "on raid10\n"); 1395 ret = -EINVAL; 1396 goto out; 1397 } 1398 1399 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) { 1400 printk(KERN_ERR "btrfs: unable to go below two " 1401 "devices on raid1\n"); 1402 ret = -EINVAL; 1403 goto out; 1404 } 1405 1406 if (strcmp(device_path, "missing") == 0) { 1407 struct list_head *devices; 1408 struct btrfs_device *tmp; 1409 1410 device = NULL; 1411 devices = &root->fs_info->fs_devices->devices; 1412 /* 1413 * It is safe to read the devices since the volume_mutex 1414 * is held. 1415 */ 1416 list_for_each_entry(tmp, devices, dev_list) { 1417 if (tmp->in_fs_metadata && 1418 !tmp->is_tgtdev_for_dev_replace && 1419 !tmp->bdev) { 1420 device = tmp; 1421 break; 1422 } 1423 } 1424 bdev = NULL; 1425 bh = NULL; 1426 disk_super = NULL; 1427 if (!device) { 1428 printk(KERN_ERR "btrfs: no missing devices found to " 1429 "remove\n"); 1430 goto out; 1431 } 1432 } else { 1433 ret = btrfs_get_bdev_and_sb(device_path, 1434 FMODE_READ | FMODE_EXCL, 1435 root->fs_info->bdev_holder, 0, 1436 &bdev, &bh); 1437 if (ret) 1438 goto out; 1439 disk_super = (struct btrfs_super_block *)bh->b_data; 1440 devid = btrfs_stack_device_id(&disk_super->dev_item); 1441 dev_uuid = disk_super->dev_item.uuid; 1442 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1443 disk_super->fsid); 1444 if (!device) { 1445 ret = -ENOENT; 1446 goto error_brelse; 1447 } 1448 } 1449 1450 if (device->is_tgtdev_for_dev_replace) { 1451 pr_err("btrfs: unable to remove the dev_replace target dev\n"); 1452 ret = -EINVAL; 1453 goto error_brelse; 1454 } 1455 1456 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) { 1457 printk(KERN_ERR "btrfs: unable to remove the only writeable " 1458 "device\n"); 1459 ret = -EINVAL; 1460 goto error_brelse; 1461 } 1462 1463 if (device->writeable) { 1464 lock_chunks(root); 1465 list_del_init(&device->dev_alloc_list); 1466 unlock_chunks(root); 1467 root->fs_info->fs_devices->rw_devices--; 1468 clear_super = true; 1469 } 1470 1471 ret = btrfs_shrink_device(device, 0); 1472 if (ret) 1473 goto error_undo; 1474 1475 /* 1476 * TODO: the superblock still includes this device in its num_devices 1477 * counter although write_all_supers() is not locked out. This 1478 * could give a filesystem state which requires a degraded mount. 1479 */ 1480 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); 1481 if (ret) 1482 goto error_undo; 1483 1484 spin_lock(&root->fs_info->free_chunk_lock); 1485 root->fs_info->free_chunk_space = device->total_bytes - 1486 device->bytes_used; 1487 spin_unlock(&root->fs_info->free_chunk_lock); 1488 1489 device->in_fs_metadata = 0; 1490 btrfs_scrub_cancel_dev(root->fs_info, device); 1491 1492 /* 1493 * the device list mutex makes sure that we don't change 1494 * the device list while someone else is writing out all 1495 * the device supers. 1496 */ 1497 1498 cur_devices = device->fs_devices; 1499 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1500 list_del_rcu(&device->dev_list); 1501 1502 device->fs_devices->num_devices--; 1503 device->fs_devices->total_devices--; 1504 1505 if (device->missing) 1506 root->fs_info->fs_devices->missing_devices--; 1507 1508 next_device = list_entry(root->fs_info->fs_devices->devices.next, 1509 struct btrfs_device, dev_list); 1510 if (device->bdev == root->fs_info->sb->s_bdev) 1511 root->fs_info->sb->s_bdev = next_device->bdev; 1512 if (device->bdev == root->fs_info->fs_devices->latest_bdev) 1513 root->fs_info->fs_devices->latest_bdev = next_device->bdev; 1514 1515 if (device->bdev) 1516 device->fs_devices->open_devices--; 1517 1518 call_rcu(&device->rcu, free_device); 1519 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1520 1521 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1; 1522 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices); 1523 1524 if (cur_devices->open_devices == 0) { 1525 struct btrfs_fs_devices *fs_devices; 1526 fs_devices = root->fs_info->fs_devices; 1527 while (fs_devices) { 1528 if (fs_devices->seed == cur_devices) 1529 break; 1530 fs_devices = fs_devices->seed; 1531 } 1532 fs_devices->seed = cur_devices->seed; 1533 cur_devices->seed = NULL; 1534 lock_chunks(root); 1535 __btrfs_close_devices(cur_devices); 1536 unlock_chunks(root); 1537 free_fs_devices(cur_devices); 1538 } 1539 1540 root->fs_info->num_tolerated_disk_barrier_failures = 1541 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 1542 1543 /* 1544 * at this point, the device is zero sized. We want to 1545 * remove it from the devices list and zero out the old super 1546 */ 1547 if (clear_super && disk_super) { 1548 /* make sure this device isn't detected as part of 1549 * the FS anymore 1550 */ 1551 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 1552 set_buffer_dirty(bh); 1553 sync_dirty_buffer(bh); 1554 } 1555 1556 ret = 0; 1557 1558 /* Notify udev that device has changed */ 1559 btrfs_kobject_uevent(bdev, KOBJ_CHANGE); 1560 1561 error_brelse: 1562 brelse(bh); 1563 if (bdev) 1564 blkdev_put(bdev, FMODE_READ | FMODE_EXCL); 1565 out: 1566 mutex_unlock(&uuid_mutex); 1567 return ret; 1568 error_undo: 1569 if (device->writeable) { 1570 lock_chunks(root); 1571 list_add(&device->dev_alloc_list, 1572 &root->fs_info->fs_devices->alloc_list); 1573 unlock_chunks(root); 1574 root->fs_info->fs_devices->rw_devices++; 1575 } 1576 goto error_brelse; 1577 } 1578 1579 void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info, 1580 struct btrfs_device *srcdev) 1581 { 1582 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex)); 1583 list_del_rcu(&srcdev->dev_list); 1584 list_del_rcu(&srcdev->dev_alloc_list); 1585 fs_info->fs_devices->num_devices--; 1586 if (srcdev->missing) { 1587 fs_info->fs_devices->missing_devices--; 1588 fs_info->fs_devices->rw_devices++; 1589 } 1590 if (srcdev->can_discard) 1591 fs_info->fs_devices->num_can_discard--; 1592 if (srcdev->bdev) 1593 fs_info->fs_devices->open_devices--; 1594 1595 call_rcu(&srcdev->rcu, free_device); 1596 } 1597 1598 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 1599 struct btrfs_device *tgtdev) 1600 { 1601 struct btrfs_device *next_device; 1602 1603 WARN_ON(!tgtdev); 1604 mutex_lock(&fs_info->fs_devices->device_list_mutex); 1605 if (tgtdev->bdev) { 1606 btrfs_scratch_superblock(tgtdev); 1607 fs_info->fs_devices->open_devices--; 1608 } 1609 fs_info->fs_devices->num_devices--; 1610 if (tgtdev->can_discard) 1611 fs_info->fs_devices->num_can_discard++; 1612 1613 next_device = list_entry(fs_info->fs_devices->devices.next, 1614 struct btrfs_device, dev_list); 1615 if (tgtdev->bdev == fs_info->sb->s_bdev) 1616 fs_info->sb->s_bdev = next_device->bdev; 1617 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev) 1618 fs_info->fs_devices->latest_bdev = next_device->bdev; 1619 list_del_rcu(&tgtdev->dev_list); 1620 1621 call_rcu(&tgtdev->rcu, free_device); 1622 1623 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 1624 } 1625 1626 int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path, 1627 struct btrfs_device **device) 1628 { 1629 int ret = 0; 1630 struct btrfs_super_block *disk_super; 1631 u64 devid; 1632 u8 *dev_uuid; 1633 struct block_device *bdev; 1634 struct buffer_head *bh; 1635 1636 *device = NULL; 1637 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ, 1638 root->fs_info->bdev_holder, 0, &bdev, &bh); 1639 if (ret) 1640 return ret; 1641 disk_super = (struct btrfs_super_block *)bh->b_data; 1642 devid = btrfs_stack_device_id(&disk_super->dev_item); 1643 dev_uuid = disk_super->dev_item.uuid; 1644 *device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1645 disk_super->fsid); 1646 brelse(bh); 1647 if (!*device) 1648 ret = -ENOENT; 1649 blkdev_put(bdev, FMODE_READ); 1650 return ret; 1651 } 1652 1653 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root, 1654 char *device_path, 1655 struct btrfs_device **device) 1656 { 1657 *device = NULL; 1658 if (strcmp(device_path, "missing") == 0) { 1659 struct list_head *devices; 1660 struct btrfs_device *tmp; 1661 1662 devices = &root->fs_info->fs_devices->devices; 1663 /* 1664 * It is safe to read the devices since the volume_mutex 1665 * is held by the caller. 1666 */ 1667 list_for_each_entry(tmp, devices, dev_list) { 1668 if (tmp->in_fs_metadata && !tmp->bdev) { 1669 *device = tmp; 1670 break; 1671 } 1672 } 1673 1674 if (!*device) { 1675 pr_err("btrfs: no missing device found\n"); 1676 return -ENOENT; 1677 } 1678 1679 return 0; 1680 } else { 1681 return btrfs_find_device_by_path(root, device_path, device); 1682 } 1683 } 1684 1685 /* 1686 * does all the dirty work required for changing file system's UUID. 1687 */ 1688 static int btrfs_prepare_sprout(struct btrfs_root *root) 1689 { 1690 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 1691 struct btrfs_fs_devices *old_devices; 1692 struct btrfs_fs_devices *seed_devices; 1693 struct btrfs_super_block *disk_super = root->fs_info->super_copy; 1694 struct btrfs_device *device; 1695 u64 super_flags; 1696 1697 BUG_ON(!mutex_is_locked(&uuid_mutex)); 1698 if (!fs_devices->seeding) 1699 return -EINVAL; 1700 1701 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 1702 if (!seed_devices) 1703 return -ENOMEM; 1704 1705 old_devices = clone_fs_devices(fs_devices); 1706 if (IS_ERR(old_devices)) { 1707 kfree(seed_devices); 1708 return PTR_ERR(old_devices); 1709 } 1710 1711 list_add(&old_devices->list, &fs_uuids); 1712 1713 memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); 1714 seed_devices->opened = 1; 1715 INIT_LIST_HEAD(&seed_devices->devices); 1716 INIT_LIST_HEAD(&seed_devices->alloc_list); 1717 mutex_init(&seed_devices->device_list_mutex); 1718 1719 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1720 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, 1721 synchronize_rcu); 1722 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1723 1724 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); 1725 list_for_each_entry(device, &seed_devices->devices, dev_list) { 1726 device->fs_devices = seed_devices; 1727 } 1728 1729 fs_devices->seeding = 0; 1730 fs_devices->num_devices = 0; 1731 fs_devices->open_devices = 0; 1732 fs_devices->total_devices = 0; 1733 fs_devices->seed = seed_devices; 1734 1735 generate_random_uuid(fs_devices->fsid); 1736 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1737 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1738 super_flags = btrfs_super_flags(disk_super) & 1739 ~BTRFS_SUPER_FLAG_SEEDING; 1740 btrfs_set_super_flags(disk_super, super_flags); 1741 1742 return 0; 1743 } 1744 1745 /* 1746 * strore the expected generation for seed devices in device items. 1747 */ 1748 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans, 1749 struct btrfs_root *root) 1750 { 1751 struct btrfs_path *path; 1752 struct extent_buffer *leaf; 1753 struct btrfs_dev_item *dev_item; 1754 struct btrfs_device *device; 1755 struct btrfs_key key; 1756 u8 fs_uuid[BTRFS_UUID_SIZE]; 1757 u8 dev_uuid[BTRFS_UUID_SIZE]; 1758 u64 devid; 1759 int ret; 1760 1761 path = btrfs_alloc_path(); 1762 if (!path) 1763 return -ENOMEM; 1764 1765 root = root->fs_info->chunk_root; 1766 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1767 key.offset = 0; 1768 key.type = BTRFS_DEV_ITEM_KEY; 1769 1770 while (1) { 1771 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 1772 if (ret < 0) 1773 goto error; 1774 1775 leaf = path->nodes[0]; 1776 next_slot: 1777 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1778 ret = btrfs_next_leaf(root, path); 1779 if (ret > 0) 1780 break; 1781 if (ret < 0) 1782 goto error; 1783 leaf = path->nodes[0]; 1784 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1785 btrfs_release_path(path); 1786 continue; 1787 } 1788 1789 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1790 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || 1791 key.type != BTRFS_DEV_ITEM_KEY) 1792 break; 1793 1794 dev_item = btrfs_item_ptr(leaf, path->slots[0], 1795 struct btrfs_dev_item); 1796 devid = btrfs_device_id(leaf, dev_item); 1797 read_extent_buffer(leaf, dev_uuid, 1798 (unsigned long)btrfs_device_uuid(dev_item), 1799 BTRFS_UUID_SIZE); 1800 read_extent_buffer(leaf, fs_uuid, 1801 (unsigned long)btrfs_device_fsid(dev_item), 1802 BTRFS_UUID_SIZE); 1803 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1804 fs_uuid); 1805 BUG_ON(!device); /* Logic error */ 1806 1807 if (device->fs_devices->seeding) { 1808 btrfs_set_device_generation(leaf, dev_item, 1809 device->generation); 1810 btrfs_mark_buffer_dirty(leaf); 1811 } 1812 1813 path->slots[0]++; 1814 goto next_slot; 1815 } 1816 ret = 0; 1817 error: 1818 btrfs_free_path(path); 1819 return ret; 1820 } 1821 1822 int btrfs_init_new_device(struct btrfs_root *root, char *device_path) 1823 { 1824 struct request_queue *q; 1825 struct btrfs_trans_handle *trans; 1826 struct btrfs_device *device; 1827 struct block_device *bdev; 1828 struct list_head *devices; 1829 struct super_block *sb = root->fs_info->sb; 1830 struct rcu_string *name; 1831 u64 total_bytes; 1832 int seeding_dev = 0; 1833 int ret = 0; 1834 1835 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) 1836 return -EROFS; 1837 1838 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 1839 root->fs_info->bdev_holder); 1840 if (IS_ERR(bdev)) 1841 return PTR_ERR(bdev); 1842 1843 if (root->fs_info->fs_devices->seeding) { 1844 seeding_dev = 1; 1845 down_write(&sb->s_umount); 1846 mutex_lock(&uuid_mutex); 1847 } 1848 1849 filemap_write_and_wait(bdev->bd_inode->i_mapping); 1850 1851 devices = &root->fs_info->fs_devices->devices; 1852 1853 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1854 list_for_each_entry(device, devices, dev_list) { 1855 if (device->bdev == bdev) { 1856 ret = -EEXIST; 1857 mutex_unlock( 1858 &root->fs_info->fs_devices->device_list_mutex); 1859 goto error; 1860 } 1861 } 1862 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1863 1864 device = kzalloc(sizeof(*device), GFP_NOFS); 1865 if (!device) { 1866 /* we can safely leave the fs_devices entry around */ 1867 ret = -ENOMEM; 1868 goto error; 1869 } 1870 1871 name = rcu_string_strdup(device_path, GFP_NOFS); 1872 if (!name) { 1873 kfree(device); 1874 ret = -ENOMEM; 1875 goto error; 1876 } 1877 rcu_assign_pointer(device->name, name); 1878 1879 ret = find_next_devid(root, &device->devid); 1880 if (ret) { 1881 rcu_string_free(device->name); 1882 kfree(device); 1883 goto error; 1884 } 1885 1886 trans = btrfs_start_transaction(root, 0); 1887 if (IS_ERR(trans)) { 1888 rcu_string_free(device->name); 1889 kfree(device); 1890 ret = PTR_ERR(trans); 1891 goto error; 1892 } 1893 1894 lock_chunks(root); 1895 1896 q = bdev_get_queue(bdev); 1897 if (blk_queue_discard(q)) 1898 device->can_discard = 1; 1899 device->writeable = 1; 1900 device->work.func = pending_bios_fn; 1901 generate_random_uuid(device->uuid); 1902 spin_lock_init(&device->io_lock); 1903 device->generation = trans->transid; 1904 device->io_width = root->sectorsize; 1905 device->io_align = root->sectorsize; 1906 device->sector_size = root->sectorsize; 1907 device->total_bytes = i_size_read(bdev->bd_inode); 1908 device->disk_total_bytes = device->total_bytes; 1909 device->dev_root = root->fs_info->dev_root; 1910 device->bdev = bdev; 1911 device->in_fs_metadata = 1; 1912 device->is_tgtdev_for_dev_replace = 0; 1913 device->mode = FMODE_EXCL; 1914 set_blocksize(device->bdev, 4096); 1915 1916 if (seeding_dev) { 1917 sb->s_flags &= ~MS_RDONLY; 1918 ret = btrfs_prepare_sprout(root); 1919 BUG_ON(ret); /* -ENOMEM */ 1920 } 1921 1922 device->fs_devices = root->fs_info->fs_devices; 1923 1924 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1925 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices); 1926 list_add(&device->dev_alloc_list, 1927 &root->fs_info->fs_devices->alloc_list); 1928 root->fs_info->fs_devices->num_devices++; 1929 root->fs_info->fs_devices->open_devices++; 1930 root->fs_info->fs_devices->rw_devices++; 1931 root->fs_info->fs_devices->total_devices++; 1932 if (device->can_discard) 1933 root->fs_info->fs_devices->num_can_discard++; 1934 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes; 1935 1936 spin_lock(&root->fs_info->free_chunk_lock); 1937 root->fs_info->free_chunk_space += device->total_bytes; 1938 spin_unlock(&root->fs_info->free_chunk_lock); 1939 1940 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 1941 root->fs_info->fs_devices->rotating = 1; 1942 1943 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); 1944 btrfs_set_super_total_bytes(root->fs_info->super_copy, 1945 total_bytes + device->total_bytes); 1946 1947 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy); 1948 btrfs_set_super_num_devices(root->fs_info->super_copy, 1949 total_bytes + 1); 1950 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1951 1952 if (seeding_dev) { 1953 ret = init_first_rw_device(trans, root, device); 1954 if (ret) { 1955 btrfs_abort_transaction(trans, root, ret); 1956 goto error_trans; 1957 } 1958 ret = btrfs_finish_sprout(trans, root); 1959 if (ret) { 1960 btrfs_abort_transaction(trans, root, ret); 1961 goto error_trans; 1962 } 1963 } else { 1964 ret = btrfs_add_device(trans, root, device); 1965 if (ret) { 1966 btrfs_abort_transaction(trans, root, ret); 1967 goto error_trans; 1968 } 1969 } 1970 1971 /* 1972 * we've got more storage, clear any full flags on the space 1973 * infos 1974 */ 1975 btrfs_clear_space_info_full(root->fs_info); 1976 1977 unlock_chunks(root); 1978 root->fs_info->num_tolerated_disk_barrier_failures = 1979 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 1980 ret = btrfs_commit_transaction(trans, root); 1981 1982 if (seeding_dev) { 1983 mutex_unlock(&uuid_mutex); 1984 up_write(&sb->s_umount); 1985 1986 if (ret) /* transaction commit */ 1987 return ret; 1988 1989 ret = btrfs_relocate_sys_chunks(root); 1990 if (ret < 0) 1991 btrfs_error(root->fs_info, ret, 1992 "Failed to relocate sys chunks after " 1993 "device initialization. This can be fixed " 1994 "using the \"btrfs balance\" command."); 1995 trans = btrfs_attach_transaction(root); 1996 if (IS_ERR(trans)) { 1997 if (PTR_ERR(trans) == -ENOENT) 1998 return 0; 1999 return PTR_ERR(trans); 2000 } 2001 ret = btrfs_commit_transaction(trans, root); 2002 } 2003 2004 return ret; 2005 2006 error_trans: 2007 unlock_chunks(root); 2008 btrfs_end_transaction(trans, root); 2009 rcu_string_free(device->name); 2010 kfree(device); 2011 error: 2012 blkdev_put(bdev, FMODE_EXCL); 2013 if (seeding_dev) { 2014 mutex_unlock(&uuid_mutex); 2015 up_write(&sb->s_umount); 2016 } 2017 return ret; 2018 } 2019 2020 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path, 2021 struct btrfs_device **device_out) 2022 { 2023 struct request_queue *q; 2024 struct btrfs_device *device; 2025 struct block_device *bdev; 2026 struct btrfs_fs_info *fs_info = root->fs_info; 2027 struct list_head *devices; 2028 struct rcu_string *name; 2029 int ret = 0; 2030 2031 *device_out = NULL; 2032 if (fs_info->fs_devices->seeding) 2033 return -EINVAL; 2034 2035 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 2036 fs_info->bdev_holder); 2037 if (IS_ERR(bdev)) 2038 return PTR_ERR(bdev); 2039 2040 filemap_write_and_wait(bdev->bd_inode->i_mapping); 2041 2042 devices = &fs_info->fs_devices->devices; 2043 list_for_each_entry(device, devices, dev_list) { 2044 if (device->bdev == bdev) { 2045 ret = -EEXIST; 2046 goto error; 2047 } 2048 } 2049 2050 device = kzalloc(sizeof(*device), GFP_NOFS); 2051 if (!device) { 2052 ret = -ENOMEM; 2053 goto error; 2054 } 2055 2056 name = rcu_string_strdup(device_path, GFP_NOFS); 2057 if (!name) { 2058 kfree(device); 2059 ret = -ENOMEM; 2060 goto error; 2061 } 2062 rcu_assign_pointer(device->name, name); 2063 2064 q = bdev_get_queue(bdev); 2065 if (blk_queue_discard(q)) 2066 device->can_discard = 1; 2067 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2068 device->writeable = 1; 2069 device->work.func = pending_bios_fn; 2070 generate_random_uuid(device->uuid); 2071 device->devid = BTRFS_DEV_REPLACE_DEVID; 2072 spin_lock_init(&device->io_lock); 2073 device->generation = 0; 2074 device->io_width = root->sectorsize; 2075 device->io_align = root->sectorsize; 2076 device->sector_size = root->sectorsize; 2077 device->total_bytes = i_size_read(bdev->bd_inode); 2078 device->disk_total_bytes = device->total_bytes; 2079 device->dev_root = fs_info->dev_root; 2080 device->bdev = bdev; 2081 device->in_fs_metadata = 1; 2082 device->is_tgtdev_for_dev_replace = 1; 2083 device->mode = FMODE_EXCL; 2084 set_blocksize(device->bdev, 4096); 2085 device->fs_devices = fs_info->fs_devices; 2086 list_add(&device->dev_list, &fs_info->fs_devices->devices); 2087 fs_info->fs_devices->num_devices++; 2088 fs_info->fs_devices->open_devices++; 2089 if (device->can_discard) 2090 fs_info->fs_devices->num_can_discard++; 2091 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2092 2093 *device_out = device; 2094 return ret; 2095 2096 error: 2097 blkdev_put(bdev, FMODE_EXCL); 2098 return ret; 2099 } 2100 2101 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, 2102 struct btrfs_device *tgtdev) 2103 { 2104 WARN_ON(fs_info->fs_devices->rw_devices == 0); 2105 tgtdev->io_width = fs_info->dev_root->sectorsize; 2106 tgtdev->io_align = fs_info->dev_root->sectorsize; 2107 tgtdev->sector_size = fs_info->dev_root->sectorsize; 2108 tgtdev->dev_root = fs_info->dev_root; 2109 tgtdev->in_fs_metadata = 1; 2110 } 2111 2112 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, 2113 struct btrfs_device *device) 2114 { 2115 int ret; 2116 struct btrfs_path *path; 2117 struct btrfs_root *root; 2118 struct btrfs_dev_item *dev_item; 2119 struct extent_buffer *leaf; 2120 struct btrfs_key key; 2121 2122 root = device->dev_root->fs_info->chunk_root; 2123 2124 path = btrfs_alloc_path(); 2125 if (!path) 2126 return -ENOMEM; 2127 2128 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 2129 key.type = BTRFS_DEV_ITEM_KEY; 2130 key.offset = device->devid; 2131 2132 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2133 if (ret < 0) 2134 goto out; 2135 2136 if (ret > 0) { 2137 ret = -ENOENT; 2138 goto out; 2139 } 2140 2141 leaf = path->nodes[0]; 2142 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 2143 2144 btrfs_set_device_id(leaf, dev_item, device->devid); 2145 btrfs_set_device_type(leaf, dev_item, device->type); 2146 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 2147 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 2148 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 2149 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes); 2150 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 2151 btrfs_mark_buffer_dirty(leaf); 2152 2153 out: 2154 btrfs_free_path(path); 2155 return ret; 2156 } 2157 2158 static int __btrfs_grow_device(struct btrfs_trans_handle *trans, 2159 struct btrfs_device *device, u64 new_size) 2160 { 2161 struct btrfs_super_block *super_copy = 2162 device->dev_root->fs_info->super_copy; 2163 u64 old_total = btrfs_super_total_bytes(super_copy); 2164 u64 diff = new_size - device->total_bytes; 2165 2166 if (!device->writeable) 2167 return -EACCES; 2168 if (new_size <= device->total_bytes || 2169 device->is_tgtdev_for_dev_replace) 2170 return -EINVAL; 2171 2172 btrfs_set_super_total_bytes(super_copy, old_total + diff); 2173 device->fs_devices->total_rw_bytes += diff; 2174 2175 device->total_bytes = new_size; 2176 device->disk_total_bytes = new_size; 2177 btrfs_clear_space_info_full(device->dev_root->fs_info); 2178 2179 return btrfs_update_device(trans, device); 2180 } 2181 2182 int btrfs_grow_device(struct btrfs_trans_handle *trans, 2183 struct btrfs_device *device, u64 new_size) 2184 { 2185 int ret; 2186 lock_chunks(device->dev_root); 2187 ret = __btrfs_grow_device(trans, device, new_size); 2188 unlock_chunks(device->dev_root); 2189 return ret; 2190 } 2191 2192 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, 2193 struct btrfs_root *root, 2194 u64 chunk_tree, u64 chunk_objectid, 2195 u64 chunk_offset) 2196 { 2197 int ret; 2198 struct btrfs_path *path; 2199 struct btrfs_key key; 2200 2201 root = root->fs_info->chunk_root; 2202 path = btrfs_alloc_path(); 2203 if (!path) 2204 return -ENOMEM; 2205 2206 key.objectid = chunk_objectid; 2207 key.offset = chunk_offset; 2208 key.type = BTRFS_CHUNK_ITEM_KEY; 2209 2210 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2211 if (ret < 0) 2212 goto out; 2213 else if (ret > 0) { /* Logic error or corruption */ 2214 btrfs_error(root->fs_info, -ENOENT, 2215 "Failed lookup while freeing chunk."); 2216 ret = -ENOENT; 2217 goto out; 2218 } 2219 2220 ret = btrfs_del_item(trans, root, path); 2221 if (ret < 0) 2222 btrfs_error(root->fs_info, ret, 2223 "Failed to delete chunk item."); 2224 out: 2225 btrfs_free_path(path); 2226 return ret; 2227 } 2228 2229 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 2230 chunk_offset) 2231 { 2232 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 2233 struct btrfs_disk_key *disk_key; 2234 struct btrfs_chunk *chunk; 2235 u8 *ptr; 2236 int ret = 0; 2237 u32 num_stripes; 2238 u32 array_size; 2239 u32 len = 0; 2240 u32 cur; 2241 struct btrfs_key key; 2242 2243 array_size = btrfs_super_sys_array_size(super_copy); 2244 2245 ptr = super_copy->sys_chunk_array; 2246 cur = 0; 2247 2248 while (cur < array_size) { 2249 disk_key = (struct btrfs_disk_key *)ptr; 2250 btrfs_disk_key_to_cpu(&key, disk_key); 2251 2252 len = sizeof(*disk_key); 2253 2254 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 2255 chunk = (struct btrfs_chunk *)(ptr + len); 2256 num_stripes = btrfs_stack_chunk_num_stripes(chunk); 2257 len += btrfs_chunk_item_size(num_stripes); 2258 } else { 2259 ret = -EIO; 2260 break; 2261 } 2262 if (key.objectid == chunk_objectid && 2263 key.offset == chunk_offset) { 2264 memmove(ptr, ptr + len, array_size - (cur + len)); 2265 array_size -= len; 2266 btrfs_set_super_sys_array_size(super_copy, array_size); 2267 } else { 2268 ptr += len; 2269 cur += len; 2270 } 2271 } 2272 return ret; 2273 } 2274 2275 static int btrfs_relocate_chunk(struct btrfs_root *root, 2276 u64 chunk_tree, u64 chunk_objectid, 2277 u64 chunk_offset) 2278 { 2279 struct extent_map_tree *em_tree; 2280 struct btrfs_root *extent_root; 2281 struct btrfs_trans_handle *trans; 2282 struct extent_map *em; 2283 struct map_lookup *map; 2284 int ret; 2285 int i; 2286 2287 root = root->fs_info->chunk_root; 2288 extent_root = root->fs_info->extent_root; 2289 em_tree = &root->fs_info->mapping_tree.map_tree; 2290 2291 ret = btrfs_can_relocate(extent_root, chunk_offset); 2292 if (ret) 2293 return -ENOSPC; 2294 2295 /* step one, relocate all the extents inside this chunk */ 2296 ret = btrfs_relocate_block_group(extent_root, chunk_offset); 2297 if (ret) 2298 return ret; 2299 2300 trans = btrfs_start_transaction(root, 0); 2301 BUG_ON(IS_ERR(trans)); 2302 2303 lock_chunks(root); 2304 2305 /* 2306 * step two, delete the device extents and the 2307 * chunk tree entries 2308 */ 2309 read_lock(&em_tree->lock); 2310 em = lookup_extent_mapping(em_tree, chunk_offset, 1); 2311 read_unlock(&em_tree->lock); 2312 2313 BUG_ON(!em || em->start > chunk_offset || 2314 em->start + em->len < chunk_offset); 2315 map = (struct map_lookup *)em->bdev; 2316 2317 for (i = 0; i < map->num_stripes; i++) { 2318 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, 2319 map->stripes[i].physical); 2320 BUG_ON(ret); 2321 2322 if (map->stripes[i].dev) { 2323 ret = btrfs_update_device(trans, map->stripes[i].dev); 2324 BUG_ON(ret); 2325 } 2326 } 2327 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, 2328 chunk_offset); 2329 2330 BUG_ON(ret); 2331 2332 trace_btrfs_chunk_free(root, map, chunk_offset, em->len); 2333 2334 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 2335 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); 2336 BUG_ON(ret); 2337 } 2338 2339 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset); 2340 BUG_ON(ret); 2341 2342 write_lock(&em_tree->lock); 2343 remove_extent_mapping(em_tree, em); 2344 write_unlock(&em_tree->lock); 2345 2346 kfree(map); 2347 em->bdev = NULL; 2348 2349 /* once for the tree */ 2350 free_extent_map(em); 2351 /* once for us */ 2352 free_extent_map(em); 2353 2354 unlock_chunks(root); 2355 btrfs_end_transaction(trans, root); 2356 return 0; 2357 } 2358 2359 static int btrfs_relocate_sys_chunks(struct btrfs_root *root) 2360 { 2361 struct btrfs_root *chunk_root = root->fs_info->chunk_root; 2362 struct btrfs_path *path; 2363 struct extent_buffer *leaf; 2364 struct btrfs_chunk *chunk; 2365 struct btrfs_key key; 2366 struct btrfs_key found_key; 2367 u64 chunk_tree = chunk_root->root_key.objectid; 2368 u64 chunk_type; 2369 bool retried = false; 2370 int failed = 0; 2371 int ret; 2372 2373 path = btrfs_alloc_path(); 2374 if (!path) 2375 return -ENOMEM; 2376 2377 again: 2378 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2379 key.offset = (u64)-1; 2380 key.type = BTRFS_CHUNK_ITEM_KEY; 2381 2382 while (1) { 2383 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2384 if (ret < 0) 2385 goto error; 2386 BUG_ON(ret == 0); /* Corruption */ 2387 2388 ret = btrfs_previous_item(chunk_root, path, key.objectid, 2389 key.type); 2390 if (ret < 0) 2391 goto error; 2392 if (ret > 0) 2393 break; 2394 2395 leaf = path->nodes[0]; 2396 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2397 2398 chunk = btrfs_item_ptr(leaf, path->slots[0], 2399 struct btrfs_chunk); 2400 chunk_type = btrfs_chunk_type(leaf, chunk); 2401 btrfs_release_path(path); 2402 2403 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { 2404 ret = btrfs_relocate_chunk(chunk_root, chunk_tree, 2405 found_key.objectid, 2406 found_key.offset); 2407 if (ret == -ENOSPC) 2408 failed++; 2409 else if (ret) 2410 BUG(); 2411 } 2412 2413 if (found_key.offset == 0) 2414 break; 2415 key.offset = found_key.offset - 1; 2416 } 2417 ret = 0; 2418 if (failed && !retried) { 2419 failed = 0; 2420 retried = true; 2421 goto again; 2422 } else if (failed && retried) { 2423 WARN_ON(1); 2424 ret = -ENOSPC; 2425 } 2426 error: 2427 btrfs_free_path(path); 2428 return ret; 2429 } 2430 2431 static int insert_balance_item(struct btrfs_root *root, 2432 struct btrfs_balance_control *bctl) 2433 { 2434 struct btrfs_trans_handle *trans; 2435 struct btrfs_balance_item *item; 2436 struct btrfs_disk_balance_args disk_bargs; 2437 struct btrfs_path *path; 2438 struct extent_buffer *leaf; 2439 struct btrfs_key key; 2440 int ret, err; 2441 2442 path = btrfs_alloc_path(); 2443 if (!path) 2444 return -ENOMEM; 2445 2446 trans = btrfs_start_transaction(root, 0); 2447 if (IS_ERR(trans)) { 2448 btrfs_free_path(path); 2449 return PTR_ERR(trans); 2450 } 2451 2452 key.objectid = BTRFS_BALANCE_OBJECTID; 2453 key.type = BTRFS_BALANCE_ITEM_KEY; 2454 key.offset = 0; 2455 2456 ret = btrfs_insert_empty_item(trans, root, path, &key, 2457 sizeof(*item)); 2458 if (ret) 2459 goto out; 2460 2461 leaf = path->nodes[0]; 2462 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 2463 2464 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); 2465 2466 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); 2467 btrfs_set_balance_data(leaf, item, &disk_bargs); 2468 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); 2469 btrfs_set_balance_meta(leaf, item, &disk_bargs); 2470 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); 2471 btrfs_set_balance_sys(leaf, item, &disk_bargs); 2472 2473 btrfs_set_balance_flags(leaf, item, bctl->flags); 2474 2475 btrfs_mark_buffer_dirty(leaf); 2476 out: 2477 btrfs_free_path(path); 2478 err = btrfs_commit_transaction(trans, root); 2479 if (err && !ret) 2480 ret = err; 2481 return ret; 2482 } 2483 2484 static int del_balance_item(struct btrfs_root *root) 2485 { 2486 struct btrfs_trans_handle *trans; 2487 struct btrfs_path *path; 2488 struct btrfs_key key; 2489 int ret, err; 2490 2491 path = btrfs_alloc_path(); 2492 if (!path) 2493 return -ENOMEM; 2494 2495 trans = btrfs_start_transaction(root, 0); 2496 if (IS_ERR(trans)) { 2497 btrfs_free_path(path); 2498 return PTR_ERR(trans); 2499 } 2500 2501 key.objectid = BTRFS_BALANCE_OBJECTID; 2502 key.type = BTRFS_BALANCE_ITEM_KEY; 2503 key.offset = 0; 2504 2505 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2506 if (ret < 0) 2507 goto out; 2508 if (ret > 0) { 2509 ret = -ENOENT; 2510 goto out; 2511 } 2512 2513 ret = btrfs_del_item(trans, root, path); 2514 out: 2515 btrfs_free_path(path); 2516 err = btrfs_commit_transaction(trans, root); 2517 if (err && !ret) 2518 ret = err; 2519 return ret; 2520 } 2521 2522 /* 2523 * This is a heuristic used to reduce the number of chunks balanced on 2524 * resume after balance was interrupted. 2525 */ 2526 static void update_balance_args(struct btrfs_balance_control *bctl) 2527 { 2528 /* 2529 * Turn on soft mode for chunk types that were being converted. 2530 */ 2531 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) 2532 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; 2533 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) 2534 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; 2535 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) 2536 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; 2537 2538 /* 2539 * Turn on usage filter if is not already used. The idea is 2540 * that chunks that we have already balanced should be 2541 * reasonably full. Don't do it for chunks that are being 2542 * converted - that will keep us from relocating unconverted 2543 * (albeit full) chunks. 2544 */ 2545 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && 2546 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2547 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; 2548 bctl->data.usage = 90; 2549 } 2550 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && 2551 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2552 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; 2553 bctl->sys.usage = 90; 2554 } 2555 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && 2556 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2557 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; 2558 bctl->meta.usage = 90; 2559 } 2560 } 2561 2562 /* 2563 * Should be called with both balance and volume mutexes held to 2564 * serialize other volume operations (add_dev/rm_dev/resize) with 2565 * restriper. Same goes for unset_balance_control. 2566 */ 2567 static void set_balance_control(struct btrfs_balance_control *bctl) 2568 { 2569 struct btrfs_fs_info *fs_info = bctl->fs_info; 2570 2571 BUG_ON(fs_info->balance_ctl); 2572 2573 spin_lock(&fs_info->balance_lock); 2574 fs_info->balance_ctl = bctl; 2575 spin_unlock(&fs_info->balance_lock); 2576 } 2577 2578 static void unset_balance_control(struct btrfs_fs_info *fs_info) 2579 { 2580 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2581 2582 BUG_ON(!fs_info->balance_ctl); 2583 2584 spin_lock(&fs_info->balance_lock); 2585 fs_info->balance_ctl = NULL; 2586 spin_unlock(&fs_info->balance_lock); 2587 2588 kfree(bctl); 2589 } 2590 2591 /* 2592 * Balance filters. Return 1 if chunk should be filtered out 2593 * (should not be balanced). 2594 */ 2595 static int chunk_profiles_filter(u64 chunk_type, 2596 struct btrfs_balance_args *bargs) 2597 { 2598 chunk_type = chunk_to_extended(chunk_type) & 2599 BTRFS_EXTENDED_PROFILE_MASK; 2600 2601 if (bargs->profiles & chunk_type) 2602 return 0; 2603 2604 return 1; 2605 } 2606 2607 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, 2608 struct btrfs_balance_args *bargs) 2609 { 2610 struct btrfs_block_group_cache *cache; 2611 u64 chunk_used, user_thresh; 2612 int ret = 1; 2613 2614 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 2615 chunk_used = btrfs_block_group_used(&cache->item); 2616 2617 user_thresh = div_factor_fine(cache->key.offset, bargs->usage); 2618 if (chunk_used < user_thresh) 2619 ret = 0; 2620 2621 btrfs_put_block_group(cache); 2622 return ret; 2623 } 2624 2625 static int chunk_devid_filter(struct extent_buffer *leaf, 2626 struct btrfs_chunk *chunk, 2627 struct btrfs_balance_args *bargs) 2628 { 2629 struct btrfs_stripe *stripe; 2630 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2631 int i; 2632 2633 for (i = 0; i < num_stripes; i++) { 2634 stripe = btrfs_stripe_nr(chunk, i); 2635 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) 2636 return 0; 2637 } 2638 2639 return 1; 2640 } 2641 2642 /* [pstart, pend) */ 2643 static int chunk_drange_filter(struct extent_buffer *leaf, 2644 struct btrfs_chunk *chunk, 2645 u64 chunk_offset, 2646 struct btrfs_balance_args *bargs) 2647 { 2648 struct btrfs_stripe *stripe; 2649 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2650 u64 stripe_offset; 2651 u64 stripe_length; 2652 int factor; 2653 int i; 2654 2655 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) 2656 return 0; 2657 2658 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP | 2659 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) 2660 factor = 2; 2661 else 2662 factor = 1; 2663 factor = num_stripes / factor; 2664 2665 for (i = 0; i < num_stripes; i++) { 2666 stripe = btrfs_stripe_nr(chunk, i); 2667 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) 2668 continue; 2669 2670 stripe_offset = btrfs_stripe_offset(leaf, stripe); 2671 stripe_length = btrfs_chunk_length(leaf, chunk); 2672 do_div(stripe_length, factor); 2673 2674 if (stripe_offset < bargs->pend && 2675 stripe_offset + stripe_length > bargs->pstart) 2676 return 0; 2677 } 2678 2679 return 1; 2680 } 2681 2682 /* [vstart, vend) */ 2683 static int chunk_vrange_filter(struct extent_buffer *leaf, 2684 struct btrfs_chunk *chunk, 2685 u64 chunk_offset, 2686 struct btrfs_balance_args *bargs) 2687 { 2688 if (chunk_offset < bargs->vend && 2689 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) 2690 /* at least part of the chunk is inside this vrange */ 2691 return 0; 2692 2693 return 1; 2694 } 2695 2696 static int chunk_soft_convert_filter(u64 chunk_type, 2697 struct btrfs_balance_args *bargs) 2698 { 2699 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) 2700 return 0; 2701 2702 chunk_type = chunk_to_extended(chunk_type) & 2703 BTRFS_EXTENDED_PROFILE_MASK; 2704 2705 if (bargs->target == chunk_type) 2706 return 1; 2707 2708 return 0; 2709 } 2710 2711 static int should_balance_chunk(struct btrfs_root *root, 2712 struct extent_buffer *leaf, 2713 struct btrfs_chunk *chunk, u64 chunk_offset) 2714 { 2715 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl; 2716 struct btrfs_balance_args *bargs = NULL; 2717 u64 chunk_type = btrfs_chunk_type(leaf, chunk); 2718 2719 /* type filter */ 2720 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & 2721 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { 2722 return 0; 2723 } 2724 2725 if (chunk_type & BTRFS_BLOCK_GROUP_DATA) 2726 bargs = &bctl->data; 2727 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) 2728 bargs = &bctl->sys; 2729 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) 2730 bargs = &bctl->meta; 2731 2732 /* profiles filter */ 2733 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && 2734 chunk_profiles_filter(chunk_type, bargs)) { 2735 return 0; 2736 } 2737 2738 /* usage filter */ 2739 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && 2740 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) { 2741 return 0; 2742 } 2743 2744 /* devid filter */ 2745 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && 2746 chunk_devid_filter(leaf, chunk, bargs)) { 2747 return 0; 2748 } 2749 2750 /* drange filter, makes sense only with devid filter */ 2751 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && 2752 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) { 2753 return 0; 2754 } 2755 2756 /* vrange filter */ 2757 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && 2758 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { 2759 return 0; 2760 } 2761 2762 /* soft profile changing mode */ 2763 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && 2764 chunk_soft_convert_filter(chunk_type, bargs)) { 2765 return 0; 2766 } 2767 2768 return 1; 2769 } 2770 2771 static int __btrfs_balance(struct btrfs_fs_info *fs_info) 2772 { 2773 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2774 struct btrfs_root *chunk_root = fs_info->chunk_root; 2775 struct btrfs_root *dev_root = fs_info->dev_root; 2776 struct list_head *devices; 2777 struct btrfs_device *device; 2778 u64 old_size; 2779 u64 size_to_free; 2780 struct btrfs_chunk *chunk; 2781 struct btrfs_path *path; 2782 struct btrfs_key key; 2783 struct btrfs_key found_key; 2784 struct btrfs_trans_handle *trans; 2785 struct extent_buffer *leaf; 2786 int slot; 2787 int ret; 2788 int enospc_errors = 0; 2789 bool counting = true; 2790 2791 /* step one make some room on all the devices */ 2792 devices = &fs_info->fs_devices->devices; 2793 list_for_each_entry(device, devices, dev_list) { 2794 old_size = device->total_bytes; 2795 size_to_free = div_factor(old_size, 1); 2796 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024); 2797 if (!device->writeable || 2798 device->total_bytes - device->bytes_used > size_to_free || 2799 device->is_tgtdev_for_dev_replace) 2800 continue; 2801 2802 ret = btrfs_shrink_device(device, old_size - size_to_free); 2803 if (ret == -ENOSPC) 2804 break; 2805 BUG_ON(ret); 2806 2807 trans = btrfs_start_transaction(dev_root, 0); 2808 BUG_ON(IS_ERR(trans)); 2809 2810 ret = btrfs_grow_device(trans, device, old_size); 2811 BUG_ON(ret); 2812 2813 btrfs_end_transaction(trans, dev_root); 2814 } 2815 2816 /* step two, relocate all the chunks */ 2817 path = btrfs_alloc_path(); 2818 if (!path) { 2819 ret = -ENOMEM; 2820 goto error; 2821 } 2822 2823 /* zero out stat counters */ 2824 spin_lock(&fs_info->balance_lock); 2825 memset(&bctl->stat, 0, sizeof(bctl->stat)); 2826 spin_unlock(&fs_info->balance_lock); 2827 again: 2828 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2829 key.offset = (u64)-1; 2830 key.type = BTRFS_CHUNK_ITEM_KEY; 2831 2832 while (1) { 2833 if ((!counting && atomic_read(&fs_info->balance_pause_req)) || 2834 atomic_read(&fs_info->balance_cancel_req)) { 2835 ret = -ECANCELED; 2836 goto error; 2837 } 2838 2839 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2840 if (ret < 0) 2841 goto error; 2842 2843 /* 2844 * this shouldn't happen, it means the last relocate 2845 * failed 2846 */ 2847 if (ret == 0) 2848 BUG(); /* FIXME break ? */ 2849 2850 ret = btrfs_previous_item(chunk_root, path, 0, 2851 BTRFS_CHUNK_ITEM_KEY); 2852 if (ret) { 2853 ret = 0; 2854 break; 2855 } 2856 2857 leaf = path->nodes[0]; 2858 slot = path->slots[0]; 2859 btrfs_item_key_to_cpu(leaf, &found_key, slot); 2860 2861 if (found_key.objectid != key.objectid) 2862 break; 2863 2864 /* chunk zero is special */ 2865 if (found_key.offset == 0) 2866 break; 2867 2868 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 2869 2870 if (!counting) { 2871 spin_lock(&fs_info->balance_lock); 2872 bctl->stat.considered++; 2873 spin_unlock(&fs_info->balance_lock); 2874 } 2875 2876 ret = should_balance_chunk(chunk_root, leaf, chunk, 2877 found_key.offset); 2878 btrfs_release_path(path); 2879 if (!ret) 2880 goto loop; 2881 2882 if (counting) { 2883 spin_lock(&fs_info->balance_lock); 2884 bctl->stat.expected++; 2885 spin_unlock(&fs_info->balance_lock); 2886 goto loop; 2887 } 2888 2889 ret = btrfs_relocate_chunk(chunk_root, 2890 chunk_root->root_key.objectid, 2891 found_key.objectid, 2892 found_key.offset); 2893 if (ret && ret != -ENOSPC) 2894 goto error; 2895 if (ret == -ENOSPC) { 2896 enospc_errors++; 2897 } else { 2898 spin_lock(&fs_info->balance_lock); 2899 bctl->stat.completed++; 2900 spin_unlock(&fs_info->balance_lock); 2901 } 2902 loop: 2903 key.offset = found_key.offset - 1; 2904 } 2905 2906 if (counting) { 2907 btrfs_release_path(path); 2908 counting = false; 2909 goto again; 2910 } 2911 error: 2912 btrfs_free_path(path); 2913 if (enospc_errors) { 2914 printk(KERN_INFO "btrfs: %d enospc errors during balance\n", 2915 enospc_errors); 2916 if (!ret) 2917 ret = -ENOSPC; 2918 } 2919 2920 return ret; 2921 } 2922 2923 /** 2924 * alloc_profile_is_valid - see if a given profile is valid and reduced 2925 * @flags: profile to validate 2926 * @extended: if true @flags is treated as an extended profile 2927 */ 2928 static int alloc_profile_is_valid(u64 flags, int extended) 2929 { 2930 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK : 2931 BTRFS_BLOCK_GROUP_PROFILE_MASK); 2932 2933 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK; 2934 2935 /* 1) check that all other bits are zeroed */ 2936 if (flags & ~mask) 2937 return 0; 2938 2939 /* 2) see if profile is reduced */ 2940 if (flags == 0) 2941 return !extended; /* "0" is valid for usual profiles */ 2942 2943 /* true if exactly one bit set */ 2944 return (flags & (flags - 1)) == 0; 2945 } 2946 2947 static inline int balance_need_close(struct btrfs_fs_info *fs_info) 2948 { 2949 /* cancel requested || normal exit path */ 2950 return atomic_read(&fs_info->balance_cancel_req) || 2951 (atomic_read(&fs_info->balance_pause_req) == 0 && 2952 atomic_read(&fs_info->balance_cancel_req) == 0); 2953 } 2954 2955 static void __cancel_balance(struct btrfs_fs_info *fs_info) 2956 { 2957 int ret; 2958 2959 unset_balance_control(fs_info); 2960 ret = del_balance_item(fs_info->tree_root); 2961 BUG_ON(ret); 2962 } 2963 2964 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 2965 struct btrfs_ioctl_balance_args *bargs); 2966 2967 /* 2968 * Should be called with both balance and volume mutexes held 2969 */ 2970 int btrfs_balance(struct btrfs_balance_control *bctl, 2971 struct btrfs_ioctl_balance_args *bargs) 2972 { 2973 struct btrfs_fs_info *fs_info = bctl->fs_info; 2974 u64 allowed; 2975 int mixed = 0; 2976 int ret; 2977 u64 num_devices; 2978 2979 if (btrfs_fs_closing(fs_info) || 2980 atomic_read(&fs_info->balance_pause_req) || 2981 atomic_read(&fs_info->balance_cancel_req)) { 2982 ret = -EINVAL; 2983 goto out; 2984 } 2985 2986 allowed = btrfs_super_incompat_flags(fs_info->super_copy); 2987 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) 2988 mixed = 1; 2989 2990 /* 2991 * In case of mixed groups both data and meta should be picked, 2992 * and identical options should be given for both of them. 2993 */ 2994 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA; 2995 if (mixed && (bctl->flags & allowed)) { 2996 if (!(bctl->flags & BTRFS_BALANCE_DATA) || 2997 !(bctl->flags & BTRFS_BALANCE_METADATA) || 2998 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { 2999 printk(KERN_ERR "btrfs: with mixed groups data and " 3000 "metadata balance options must be the same\n"); 3001 ret = -EINVAL; 3002 goto out; 3003 } 3004 } 3005 3006 num_devices = fs_info->fs_devices->num_devices; 3007 btrfs_dev_replace_lock(&fs_info->dev_replace); 3008 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { 3009 BUG_ON(num_devices < 1); 3010 num_devices--; 3011 } 3012 btrfs_dev_replace_unlock(&fs_info->dev_replace); 3013 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; 3014 if (num_devices == 1) 3015 allowed |= BTRFS_BLOCK_GROUP_DUP; 3016 else if (num_devices < 4) 3017 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1); 3018 else 3019 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | 3020 BTRFS_BLOCK_GROUP_RAID10); 3021 3022 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3023 (!alloc_profile_is_valid(bctl->data.target, 1) || 3024 (bctl->data.target & ~allowed))) { 3025 printk(KERN_ERR "btrfs: unable to start balance with target " 3026 "data profile %llu\n", 3027 (unsigned long long)bctl->data.target); 3028 ret = -EINVAL; 3029 goto out; 3030 } 3031 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3032 (!alloc_profile_is_valid(bctl->meta.target, 1) || 3033 (bctl->meta.target & ~allowed))) { 3034 printk(KERN_ERR "btrfs: unable to start balance with target " 3035 "metadata profile %llu\n", 3036 (unsigned long long)bctl->meta.target); 3037 ret = -EINVAL; 3038 goto out; 3039 } 3040 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3041 (!alloc_profile_is_valid(bctl->sys.target, 1) || 3042 (bctl->sys.target & ~allowed))) { 3043 printk(KERN_ERR "btrfs: unable to start balance with target " 3044 "system profile %llu\n", 3045 (unsigned long long)bctl->sys.target); 3046 ret = -EINVAL; 3047 goto out; 3048 } 3049 3050 /* allow dup'ed data chunks only in mixed mode */ 3051 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3052 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) { 3053 printk(KERN_ERR "btrfs: dup for data is not allowed\n"); 3054 ret = -EINVAL; 3055 goto out; 3056 } 3057 3058 /* allow to reduce meta or sys integrity only if force set */ 3059 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | 3060 BTRFS_BLOCK_GROUP_RAID10; 3061 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3062 (fs_info->avail_system_alloc_bits & allowed) && 3063 !(bctl->sys.target & allowed)) || 3064 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3065 (fs_info->avail_metadata_alloc_bits & allowed) && 3066 !(bctl->meta.target & allowed))) { 3067 if (bctl->flags & BTRFS_BALANCE_FORCE) { 3068 printk(KERN_INFO "btrfs: force reducing metadata " 3069 "integrity\n"); 3070 } else { 3071 printk(KERN_ERR "btrfs: balance will reduce metadata " 3072 "integrity, use force if you want this\n"); 3073 ret = -EINVAL; 3074 goto out; 3075 } 3076 } 3077 3078 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3079 int num_tolerated_disk_barrier_failures; 3080 u64 target = bctl->sys.target; 3081 3082 num_tolerated_disk_barrier_failures = 3083 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3084 if (num_tolerated_disk_barrier_failures > 0 && 3085 (target & 3086 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 | 3087 BTRFS_AVAIL_ALLOC_BIT_SINGLE))) 3088 num_tolerated_disk_barrier_failures = 0; 3089 else if (num_tolerated_disk_barrier_failures > 1 && 3090 (target & 3091 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10))) 3092 num_tolerated_disk_barrier_failures = 1; 3093 3094 fs_info->num_tolerated_disk_barrier_failures = 3095 num_tolerated_disk_barrier_failures; 3096 } 3097 3098 ret = insert_balance_item(fs_info->tree_root, bctl); 3099 if (ret && ret != -EEXIST) 3100 goto out; 3101 3102 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { 3103 BUG_ON(ret == -EEXIST); 3104 set_balance_control(bctl); 3105 } else { 3106 BUG_ON(ret != -EEXIST); 3107 spin_lock(&fs_info->balance_lock); 3108 update_balance_args(bctl); 3109 spin_unlock(&fs_info->balance_lock); 3110 } 3111 3112 atomic_inc(&fs_info->balance_running); 3113 mutex_unlock(&fs_info->balance_mutex); 3114 3115 ret = __btrfs_balance(fs_info); 3116 3117 mutex_lock(&fs_info->balance_mutex); 3118 atomic_dec(&fs_info->balance_running); 3119 3120 if (bargs) { 3121 memset(bargs, 0, sizeof(*bargs)); 3122 update_ioctl_balance_args(fs_info, 0, bargs); 3123 } 3124 3125 if ((ret && ret != -ECANCELED && ret != -ENOSPC) || 3126 balance_need_close(fs_info)) { 3127 __cancel_balance(fs_info); 3128 } 3129 3130 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3131 fs_info->num_tolerated_disk_barrier_failures = 3132 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3133 } 3134 3135 wake_up(&fs_info->balance_wait_q); 3136 3137 return ret; 3138 out: 3139 if (bctl->flags & BTRFS_BALANCE_RESUME) 3140 __cancel_balance(fs_info); 3141 else 3142 kfree(bctl); 3143 return ret; 3144 } 3145 3146 static int balance_kthread(void *data) 3147 { 3148 struct btrfs_fs_info *fs_info = data; 3149 int ret = 0; 3150 3151 mutex_lock(&fs_info->volume_mutex); 3152 mutex_lock(&fs_info->balance_mutex); 3153 3154 if (fs_info->balance_ctl) { 3155 printk(KERN_INFO "btrfs: continuing balance\n"); 3156 ret = btrfs_balance(fs_info->balance_ctl, NULL); 3157 } 3158 3159 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3160 mutex_unlock(&fs_info->balance_mutex); 3161 mutex_unlock(&fs_info->volume_mutex); 3162 3163 return ret; 3164 } 3165 3166 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info) 3167 { 3168 struct task_struct *tsk; 3169 3170 spin_lock(&fs_info->balance_lock); 3171 if (!fs_info->balance_ctl) { 3172 spin_unlock(&fs_info->balance_lock); 3173 return 0; 3174 } 3175 spin_unlock(&fs_info->balance_lock); 3176 3177 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) { 3178 printk(KERN_INFO "btrfs: force skipping balance\n"); 3179 return 0; 3180 } 3181 3182 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)); 3183 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance"); 3184 if (IS_ERR(tsk)) 3185 return PTR_ERR(tsk); 3186 3187 return 0; 3188 } 3189 3190 int btrfs_recover_balance(struct btrfs_fs_info *fs_info) 3191 { 3192 struct btrfs_balance_control *bctl; 3193 struct btrfs_balance_item *item; 3194 struct btrfs_disk_balance_args disk_bargs; 3195 struct btrfs_path *path; 3196 struct extent_buffer *leaf; 3197 struct btrfs_key key; 3198 int ret; 3199 3200 path = btrfs_alloc_path(); 3201 if (!path) 3202 return -ENOMEM; 3203 3204 key.objectid = BTRFS_BALANCE_OBJECTID; 3205 key.type = BTRFS_BALANCE_ITEM_KEY; 3206 key.offset = 0; 3207 3208 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 3209 if (ret < 0) 3210 goto out; 3211 if (ret > 0) { /* ret = -ENOENT; */ 3212 ret = 0; 3213 goto out; 3214 } 3215 3216 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3217 if (!bctl) { 3218 ret = -ENOMEM; 3219 goto out; 3220 } 3221 3222 leaf = path->nodes[0]; 3223 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 3224 3225 bctl->fs_info = fs_info; 3226 bctl->flags = btrfs_balance_flags(leaf, item); 3227 bctl->flags |= BTRFS_BALANCE_RESUME; 3228 3229 btrfs_balance_data(leaf, item, &disk_bargs); 3230 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); 3231 btrfs_balance_meta(leaf, item, &disk_bargs); 3232 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); 3233 btrfs_balance_sys(leaf, item, &disk_bargs); 3234 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); 3235 3236 mutex_lock(&fs_info->volume_mutex); 3237 mutex_lock(&fs_info->balance_mutex); 3238 3239 set_balance_control(bctl); 3240 3241 mutex_unlock(&fs_info->balance_mutex); 3242 mutex_unlock(&fs_info->volume_mutex); 3243 out: 3244 btrfs_free_path(path); 3245 return ret; 3246 } 3247 3248 int btrfs_pause_balance(struct btrfs_fs_info *fs_info) 3249 { 3250 int ret = 0; 3251 3252 mutex_lock(&fs_info->balance_mutex); 3253 if (!fs_info->balance_ctl) { 3254 mutex_unlock(&fs_info->balance_mutex); 3255 return -ENOTCONN; 3256 } 3257 3258 if (atomic_read(&fs_info->balance_running)) { 3259 atomic_inc(&fs_info->balance_pause_req); 3260 mutex_unlock(&fs_info->balance_mutex); 3261 3262 wait_event(fs_info->balance_wait_q, 3263 atomic_read(&fs_info->balance_running) == 0); 3264 3265 mutex_lock(&fs_info->balance_mutex); 3266 /* we are good with balance_ctl ripped off from under us */ 3267 BUG_ON(atomic_read(&fs_info->balance_running)); 3268 atomic_dec(&fs_info->balance_pause_req); 3269 } else { 3270 ret = -ENOTCONN; 3271 } 3272 3273 mutex_unlock(&fs_info->balance_mutex); 3274 return ret; 3275 } 3276 3277 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) 3278 { 3279 mutex_lock(&fs_info->balance_mutex); 3280 if (!fs_info->balance_ctl) { 3281 mutex_unlock(&fs_info->balance_mutex); 3282 return -ENOTCONN; 3283 } 3284 3285 atomic_inc(&fs_info->balance_cancel_req); 3286 /* 3287 * if we are running just wait and return, balance item is 3288 * deleted in btrfs_balance in this case 3289 */ 3290 if (atomic_read(&fs_info->balance_running)) { 3291 mutex_unlock(&fs_info->balance_mutex); 3292 wait_event(fs_info->balance_wait_q, 3293 atomic_read(&fs_info->balance_running) == 0); 3294 mutex_lock(&fs_info->balance_mutex); 3295 } else { 3296 /* __cancel_balance needs volume_mutex */ 3297 mutex_unlock(&fs_info->balance_mutex); 3298 mutex_lock(&fs_info->volume_mutex); 3299 mutex_lock(&fs_info->balance_mutex); 3300 3301 if (fs_info->balance_ctl) 3302 __cancel_balance(fs_info); 3303 3304 mutex_unlock(&fs_info->volume_mutex); 3305 } 3306 3307 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running)); 3308 atomic_dec(&fs_info->balance_cancel_req); 3309 mutex_unlock(&fs_info->balance_mutex); 3310 return 0; 3311 } 3312 3313 /* 3314 * shrinking a device means finding all of the device extents past 3315 * the new size, and then following the back refs to the chunks. 3316 * The chunk relocation code actually frees the device extent 3317 */ 3318 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 3319 { 3320 struct btrfs_trans_handle *trans; 3321 struct btrfs_root *root = device->dev_root; 3322 struct btrfs_dev_extent *dev_extent = NULL; 3323 struct btrfs_path *path; 3324 u64 length; 3325 u64 chunk_tree; 3326 u64 chunk_objectid; 3327 u64 chunk_offset; 3328 int ret; 3329 int slot; 3330 int failed = 0; 3331 bool retried = false; 3332 struct extent_buffer *l; 3333 struct btrfs_key key; 3334 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3335 u64 old_total = btrfs_super_total_bytes(super_copy); 3336 u64 old_size = device->total_bytes; 3337 u64 diff = device->total_bytes - new_size; 3338 3339 if (device->is_tgtdev_for_dev_replace) 3340 return -EINVAL; 3341 3342 path = btrfs_alloc_path(); 3343 if (!path) 3344 return -ENOMEM; 3345 3346 path->reada = 2; 3347 3348 lock_chunks(root); 3349 3350 device->total_bytes = new_size; 3351 if (device->writeable) { 3352 device->fs_devices->total_rw_bytes -= diff; 3353 spin_lock(&root->fs_info->free_chunk_lock); 3354 root->fs_info->free_chunk_space -= diff; 3355 spin_unlock(&root->fs_info->free_chunk_lock); 3356 } 3357 unlock_chunks(root); 3358 3359 again: 3360 key.objectid = device->devid; 3361 key.offset = (u64)-1; 3362 key.type = BTRFS_DEV_EXTENT_KEY; 3363 3364 do { 3365 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3366 if (ret < 0) 3367 goto done; 3368 3369 ret = btrfs_previous_item(root, path, 0, key.type); 3370 if (ret < 0) 3371 goto done; 3372 if (ret) { 3373 ret = 0; 3374 btrfs_release_path(path); 3375 break; 3376 } 3377 3378 l = path->nodes[0]; 3379 slot = path->slots[0]; 3380 btrfs_item_key_to_cpu(l, &key, path->slots[0]); 3381 3382 if (key.objectid != device->devid) { 3383 btrfs_release_path(path); 3384 break; 3385 } 3386 3387 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 3388 length = btrfs_dev_extent_length(l, dev_extent); 3389 3390 if (key.offset + length <= new_size) { 3391 btrfs_release_path(path); 3392 break; 3393 } 3394 3395 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); 3396 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); 3397 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); 3398 btrfs_release_path(path); 3399 3400 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, 3401 chunk_offset); 3402 if (ret && ret != -ENOSPC) 3403 goto done; 3404 if (ret == -ENOSPC) 3405 failed++; 3406 } while (key.offset-- > 0); 3407 3408 if (failed && !retried) { 3409 failed = 0; 3410 retried = true; 3411 goto again; 3412 } else if (failed && retried) { 3413 ret = -ENOSPC; 3414 lock_chunks(root); 3415 3416 device->total_bytes = old_size; 3417 if (device->writeable) 3418 device->fs_devices->total_rw_bytes += diff; 3419 spin_lock(&root->fs_info->free_chunk_lock); 3420 root->fs_info->free_chunk_space += diff; 3421 spin_unlock(&root->fs_info->free_chunk_lock); 3422 unlock_chunks(root); 3423 goto done; 3424 } 3425 3426 /* Shrinking succeeded, else we would be at "done". */ 3427 trans = btrfs_start_transaction(root, 0); 3428 if (IS_ERR(trans)) { 3429 ret = PTR_ERR(trans); 3430 goto done; 3431 } 3432 3433 lock_chunks(root); 3434 3435 device->disk_total_bytes = new_size; 3436 /* Now btrfs_update_device() will change the on-disk size. */ 3437 ret = btrfs_update_device(trans, device); 3438 if (ret) { 3439 unlock_chunks(root); 3440 btrfs_end_transaction(trans, root); 3441 goto done; 3442 } 3443 WARN_ON(diff > old_total); 3444 btrfs_set_super_total_bytes(super_copy, old_total - diff); 3445 unlock_chunks(root); 3446 btrfs_end_transaction(trans, root); 3447 done: 3448 btrfs_free_path(path); 3449 return ret; 3450 } 3451 3452 static int btrfs_add_system_chunk(struct btrfs_root *root, 3453 struct btrfs_key *key, 3454 struct btrfs_chunk *chunk, int item_size) 3455 { 3456 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3457 struct btrfs_disk_key disk_key; 3458 u32 array_size; 3459 u8 *ptr; 3460 3461 array_size = btrfs_super_sys_array_size(super_copy); 3462 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) 3463 return -EFBIG; 3464 3465 ptr = super_copy->sys_chunk_array + array_size; 3466 btrfs_cpu_key_to_disk(&disk_key, key); 3467 memcpy(ptr, &disk_key, sizeof(disk_key)); 3468 ptr += sizeof(disk_key); 3469 memcpy(ptr, chunk, item_size); 3470 item_size += sizeof(disk_key); 3471 btrfs_set_super_sys_array_size(super_copy, array_size + item_size); 3472 return 0; 3473 } 3474 3475 /* 3476 * sort the devices in descending order by max_avail, total_avail 3477 */ 3478 static int btrfs_cmp_device_info(const void *a, const void *b) 3479 { 3480 const struct btrfs_device_info *di_a = a; 3481 const struct btrfs_device_info *di_b = b; 3482 3483 if (di_a->max_avail > di_b->max_avail) 3484 return -1; 3485 if (di_a->max_avail < di_b->max_avail) 3486 return 1; 3487 if (di_a->total_avail > di_b->total_avail) 3488 return -1; 3489 if (di_a->total_avail < di_b->total_avail) 3490 return 1; 3491 return 0; 3492 } 3493 3494 struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { 3495 { 2, 1, 0, 4, 2, 2 /* raid10 */ }, 3496 { 1, 1, 2, 2, 2, 2 /* raid1 */ }, 3497 { 1, 2, 1, 1, 1, 2 /* dup */ }, 3498 { 1, 1, 0, 2, 1, 1 /* raid0 */ }, 3499 { 1, 1, 0, 1, 1, 1 /* single */ }, 3500 }; 3501 3502 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 3503 struct btrfs_root *extent_root, 3504 struct map_lookup **map_ret, 3505 u64 *num_bytes_out, u64 *stripe_size_out, 3506 u64 start, u64 type) 3507 { 3508 struct btrfs_fs_info *info = extent_root->fs_info; 3509 struct btrfs_fs_devices *fs_devices = info->fs_devices; 3510 struct list_head *cur; 3511 struct map_lookup *map = NULL; 3512 struct extent_map_tree *em_tree; 3513 struct extent_map *em; 3514 struct btrfs_device_info *devices_info = NULL; 3515 u64 total_avail; 3516 int num_stripes; /* total number of stripes to allocate */ 3517 int sub_stripes; /* sub_stripes info for map */ 3518 int dev_stripes; /* stripes per dev */ 3519 int devs_max; /* max devs to use */ 3520 int devs_min; /* min devs needed */ 3521 int devs_increment; /* ndevs has to be a multiple of this */ 3522 int ncopies; /* how many copies to data has */ 3523 int ret; 3524 u64 max_stripe_size; 3525 u64 max_chunk_size; 3526 u64 stripe_size; 3527 u64 num_bytes; 3528 int ndevs; 3529 int i; 3530 int j; 3531 int index; 3532 3533 BUG_ON(!alloc_profile_is_valid(type, 0)); 3534 3535 if (list_empty(&fs_devices->alloc_list)) 3536 return -ENOSPC; 3537 3538 index = __get_raid_index(type); 3539 3540 sub_stripes = btrfs_raid_array[index].sub_stripes; 3541 dev_stripes = btrfs_raid_array[index].dev_stripes; 3542 devs_max = btrfs_raid_array[index].devs_max; 3543 devs_min = btrfs_raid_array[index].devs_min; 3544 devs_increment = btrfs_raid_array[index].devs_increment; 3545 ncopies = btrfs_raid_array[index].ncopies; 3546 3547 if (type & BTRFS_BLOCK_GROUP_DATA) { 3548 max_stripe_size = 1024 * 1024 * 1024; 3549 max_chunk_size = 10 * max_stripe_size; 3550 } else if (type & BTRFS_BLOCK_GROUP_METADATA) { 3551 /* for larger filesystems, use larger metadata chunks */ 3552 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024) 3553 max_stripe_size = 1024 * 1024 * 1024; 3554 else 3555 max_stripe_size = 256 * 1024 * 1024; 3556 max_chunk_size = max_stripe_size; 3557 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { 3558 max_stripe_size = 32 * 1024 * 1024; 3559 max_chunk_size = 2 * max_stripe_size; 3560 } else { 3561 printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n", 3562 type); 3563 BUG_ON(1); 3564 } 3565 3566 /* we don't want a chunk larger than 10% of writeable space */ 3567 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1), 3568 max_chunk_size); 3569 3570 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices, 3571 GFP_NOFS); 3572 if (!devices_info) 3573 return -ENOMEM; 3574 3575 cur = fs_devices->alloc_list.next; 3576 3577 /* 3578 * in the first pass through the devices list, we gather information 3579 * about the available holes on each device. 3580 */ 3581 ndevs = 0; 3582 while (cur != &fs_devices->alloc_list) { 3583 struct btrfs_device *device; 3584 u64 max_avail; 3585 u64 dev_offset; 3586 3587 device = list_entry(cur, struct btrfs_device, dev_alloc_list); 3588 3589 cur = cur->next; 3590 3591 if (!device->writeable) { 3592 WARN(1, KERN_ERR 3593 "btrfs: read-only device in alloc_list\n"); 3594 continue; 3595 } 3596 3597 if (!device->in_fs_metadata || 3598 device->is_tgtdev_for_dev_replace) 3599 continue; 3600 3601 if (device->total_bytes > device->bytes_used) 3602 total_avail = device->total_bytes - device->bytes_used; 3603 else 3604 total_avail = 0; 3605 3606 /* If there is no space on this device, skip it. */ 3607 if (total_avail == 0) 3608 continue; 3609 3610 ret = find_free_dev_extent(device, 3611 max_stripe_size * dev_stripes, 3612 &dev_offset, &max_avail); 3613 if (ret && ret != -ENOSPC) 3614 goto error; 3615 3616 if (ret == 0) 3617 max_avail = max_stripe_size * dev_stripes; 3618 3619 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes) 3620 continue; 3621 3622 devices_info[ndevs].dev_offset = dev_offset; 3623 devices_info[ndevs].max_avail = max_avail; 3624 devices_info[ndevs].total_avail = total_avail; 3625 devices_info[ndevs].dev = device; 3626 ++ndevs; 3627 WARN_ON(ndevs > fs_devices->rw_devices); 3628 } 3629 3630 /* 3631 * now sort the devices by hole size / available space 3632 */ 3633 sort(devices_info, ndevs, sizeof(struct btrfs_device_info), 3634 btrfs_cmp_device_info, NULL); 3635 3636 /* round down to number of usable stripes */ 3637 ndevs -= ndevs % devs_increment; 3638 3639 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) { 3640 ret = -ENOSPC; 3641 goto error; 3642 } 3643 3644 if (devs_max && ndevs > devs_max) 3645 ndevs = devs_max; 3646 /* 3647 * the primary goal is to maximize the number of stripes, so use as many 3648 * devices as possible, even if the stripes are not maximum sized. 3649 */ 3650 stripe_size = devices_info[ndevs-1].max_avail; 3651 num_stripes = ndevs * dev_stripes; 3652 3653 if (stripe_size * ndevs > max_chunk_size * ncopies) { 3654 stripe_size = max_chunk_size * ncopies; 3655 do_div(stripe_size, ndevs); 3656 } 3657 3658 do_div(stripe_size, dev_stripes); 3659 3660 /* align to BTRFS_STRIPE_LEN */ 3661 do_div(stripe_size, BTRFS_STRIPE_LEN); 3662 stripe_size *= BTRFS_STRIPE_LEN; 3663 3664 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 3665 if (!map) { 3666 ret = -ENOMEM; 3667 goto error; 3668 } 3669 map->num_stripes = num_stripes; 3670 3671 for (i = 0; i < ndevs; ++i) { 3672 for (j = 0; j < dev_stripes; ++j) { 3673 int s = i * dev_stripes + j; 3674 map->stripes[s].dev = devices_info[i].dev; 3675 map->stripes[s].physical = devices_info[i].dev_offset + 3676 j * stripe_size; 3677 } 3678 } 3679 map->sector_size = extent_root->sectorsize; 3680 map->stripe_len = BTRFS_STRIPE_LEN; 3681 map->io_align = BTRFS_STRIPE_LEN; 3682 map->io_width = BTRFS_STRIPE_LEN; 3683 map->type = type; 3684 map->sub_stripes = sub_stripes; 3685 3686 *map_ret = map; 3687 num_bytes = stripe_size * (num_stripes / ncopies); 3688 3689 *stripe_size_out = stripe_size; 3690 *num_bytes_out = num_bytes; 3691 3692 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes); 3693 3694 em = alloc_extent_map(); 3695 if (!em) { 3696 ret = -ENOMEM; 3697 goto error; 3698 } 3699 em->bdev = (struct block_device *)map; 3700 em->start = start; 3701 em->len = num_bytes; 3702 em->block_start = 0; 3703 em->block_len = em->len; 3704 3705 em_tree = &extent_root->fs_info->mapping_tree.map_tree; 3706 write_lock(&em_tree->lock); 3707 ret = add_extent_mapping(em_tree, em); 3708 write_unlock(&em_tree->lock); 3709 free_extent_map(em); 3710 if (ret) 3711 goto error; 3712 3713 ret = btrfs_make_block_group(trans, extent_root, 0, type, 3714 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3715 start, num_bytes); 3716 if (ret) 3717 goto error; 3718 3719 for (i = 0; i < map->num_stripes; ++i) { 3720 struct btrfs_device *device; 3721 u64 dev_offset; 3722 3723 device = map->stripes[i].dev; 3724 dev_offset = map->stripes[i].physical; 3725 3726 ret = btrfs_alloc_dev_extent(trans, device, 3727 info->chunk_root->root_key.objectid, 3728 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3729 start, dev_offset, stripe_size); 3730 if (ret) { 3731 btrfs_abort_transaction(trans, extent_root, ret); 3732 goto error; 3733 } 3734 } 3735 3736 kfree(devices_info); 3737 return 0; 3738 3739 error: 3740 kfree(map); 3741 kfree(devices_info); 3742 return ret; 3743 } 3744 3745 static int __finish_chunk_alloc(struct btrfs_trans_handle *trans, 3746 struct btrfs_root *extent_root, 3747 struct map_lookup *map, u64 chunk_offset, 3748 u64 chunk_size, u64 stripe_size) 3749 { 3750 u64 dev_offset; 3751 struct btrfs_key key; 3752 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 3753 struct btrfs_device *device; 3754 struct btrfs_chunk *chunk; 3755 struct btrfs_stripe *stripe; 3756 size_t item_size = btrfs_chunk_item_size(map->num_stripes); 3757 int index = 0; 3758 int ret; 3759 3760 chunk = kzalloc(item_size, GFP_NOFS); 3761 if (!chunk) 3762 return -ENOMEM; 3763 3764 index = 0; 3765 while (index < map->num_stripes) { 3766 device = map->stripes[index].dev; 3767 device->bytes_used += stripe_size; 3768 ret = btrfs_update_device(trans, device); 3769 if (ret) 3770 goto out_free; 3771 index++; 3772 } 3773 3774 spin_lock(&extent_root->fs_info->free_chunk_lock); 3775 extent_root->fs_info->free_chunk_space -= (stripe_size * 3776 map->num_stripes); 3777 spin_unlock(&extent_root->fs_info->free_chunk_lock); 3778 3779 index = 0; 3780 stripe = &chunk->stripe; 3781 while (index < map->num_stripes) { 3782 device = map->stripes[index].dev; 3783 dev_offset = map->stripes[index].physical; 3784 3785 btrfs_set_stack_stripe_devid(stripe, device->devid); 3786 btrfs_set_stack_stripe_offset(stripe, dev_offset); 3787 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); 3788 stripe++; 3789 index++; 3790 } 3791 3792 btrfs_set_stack_chunk_length(chunk, chunk_size); 3793 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); 3794 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); 3795 btrfs_set_stack_chunk_type(chunk, map->type); 3796 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); 3797 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); 3798 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); 3799 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); 3800 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); 3801 3802 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 3803 key.type = BTRFS_CHUNK_ITEM_KEY; 3804 key.offset = chunk_offset; 3805 3806 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); 3807 3808 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 3809 /* 3810 * TODO: Cleanup of inserted chunk root in case of 3811 * failure. 3812 */ 3813 ret = btrfs_add_system_chunk(chunk_root, &key, chunk, 3814 item_size); 3815 } 3816 3817 out_free: 3818 kfree(chunk); 3819 return ret; 3820 } 3821 3822 /* 3823 * Chunk allocation falls into two parts. The first part does works 3824 * that make the new allocated chunk useable, but not do any operation 3825 * that modifies the chunk tree. The second part does the works that 3826 * require modifying the chunk tree. This division is important for the 3827 * bootstrap process of adding storage to a seed btrfs. 3828 */ 3829 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 3830 struct btrfs_root *extent_root, u64 type) 3831 { 3832 u64 chunk_offset; 3833 u64 chunk_size; 3834 u64 stripe_size; 3835 struct map_lookup *map; 3836 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 3837 int ret; 3838 3839 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3840 &chunk_offset); 3841 if (ret) 3842 return ret; 3843 3844 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, 3845 &stripe_size, chunk_offset, type); 3846 if (ret) 3847 return ret; 3848 3849 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, 3850 chunk_size, stripe_size); 3851 if (ret) 3852 return ret; 3853 return 0; 3854 } 3855 3856 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans, 3857 struct btrfs_root *root, 3858 struct btrfs_device *device) 3859 { 3860 u64 chunk_offset; 3861 u64 sys_chunk_offset; 3862 u64 chunk_size; 3863 u64 sys_chunk_size; 3864 u64 stripe_size; 3865 u64 sys_stripe_size; 3866 u64 alloc_profile; 3867 struct map_lookup *map; 3868 struct map_lookup *sys_map; 3869 struct btrfs_fs_info *fs_info = root->fs_info; 3870 struct btrfs_root *extent_root = fs_info->extent_root; 3871 int ret; 3872 3873 ret = find_next_chunk(fs_info->chunk_root, 3874 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset); 3875 if (ret) 3876 return ret; 3877 3878 alloc_profile = BTRFS_BLOCK_GROUP_METADATA | 3879 fs_info->avail_metadata_alloc_bits; 3880 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile); 3881 3882 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, 3883 &stripe_size, chunk_offset, alloc_profile); 3884 if (ret) 3885 return ret; 3886 3887 sys_chunk_offset = chunk_offset + chunk_size; 3888 3889 alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM | 3890 fs_info->avail_system_alloc_bits; 3891 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile); 3892 3893 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map, 3894 &sys_chunk_size, &sys_stripe_size, 3895 sys_chunk_offset, alloc_profile); 3896 if (ret) { 3897 btrfs_abort_transaction(trans, root, ret); 3898 goto out; 3899 } 3900 3901 ret = btrfs_add_device(trans, fs_info->chunk_root, device); 3902 if (ret) { 3903 btrfs_abort_transaction(trans, root, ret); 3904 goto out; 3905 } 3906 3907 /* 3908 * Modifying chunk tree needs allocating new blocks from both 3909 * system block group and metadata block group. So we only can 3910 * do operations require modifying the chunk tree after both 3911 * block groups were created. 3912 */ 3913 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, 3914 chunk_size, stripe_size); 3915 if (ret) { 3916 btrfs_abort_transaction(trans, root, ret); 3917 goto out; 3918 } 3919 3920 ret = __finish_chunk_alloc(trans, extent_root, sys_map, 3921 sys_chunk_offset, sys_chunk_size, 3922 sys_stripe_size); 3923 if (ret) 3924 btrfs_abort_transaction(trans, root, ret); 3925 3926 out: 3927 3928 return ret; 3929 } 3930 3931 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) 3932 { 3933 struct extent_map *em; 3934 struct map_lookup *map; 3935 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 3936 int readonly = 0; 3937 int i; 3938 3939 read_lock(&map_tree->map_tree.lock); 3940 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); 3941 read_unlock(&map_tree->map_tree.lock); 3942 if (!em) 3943 return 1; 3944 3945 if (btrfs_test_opt(root, DEGRADED)) { 3946 free_extent_map(em); 3947 return 0; 3948 } 3949 3950 map = (struct map_lookup *)em->bdev; 3951 for (i = 0; i < map->num_stripes; i++) { 3952 if (!map->stripes[i].dev->writeable) { 3953 readonly = 1; 3954 break; 3955 } 3956 } 3957 free_extent_map(em); 3958 return readonly; 3959 } 3960 3961 void btrfs_mapping_init(struct btrfs_mapping_tree *tree) 3962 { 3963 extent_map_tree_init(&tree->map_tree); 3964 } 3965 3966 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree) 3967 { 3968 struct extent_map *em; 3969 3970 while (1) { 3971 write_lock(&tree->map_tree.lock); 3972 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1); 3973 if (em) 3974 remove_extent_mapping(&tree->map_tree, em); 3975 write_unlock(&tree->map_tree.lock); 3976 if (!em) 3977 break; 3978 kfree(em->bdev); 3979 /* once for us */ 3980 free_extent_map(em); 3981 /* once for the tree */ 3982 free_extent_map(em); 3983 } 3984 } 3985 3986 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) 3987 { 3988 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 3989 struct extent_map *em; 3990 struct map_lookup *map; 3991 struct extent_map_tree *em_tree = &map_tree->map_tree; 3992 int ret; 3993 3994 read_lock(&em_tree->lock); 3995 em = lookup_extent_mapping(em_tree, logical, len); 3996 read_unlock(&em_tree->lock); 3997 BUG_ON(!em); 3998 3999 BUG_ON(em->start > logical || em->start + em->len < logical); 4000 map = (struct map_lookup *)em->bdev; 4001 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1)) 4002 ret = map->num_stripes; 4003 else if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4004 ret = map->sub_stripes; 4005 else 4006 ret = 1; 4007 free_extent_map(em); 4008 4009 btrfs_dev_replace_lock(&fs_info->dev_replace); 4010 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) 4011 ret++; 4012 btrfs_dev_replace_unlock(&fs_info->dev_replace); 4013 4014 return ret; 4015 } 4016 4017 static int find_live_mirror(struct btrfs_fs_info *fs_info, 4018 struct map_lookup *map, int first, int num, 4019 int optimal, int dev_replace_is_ongoing) 4020 { 4021 int i; 4022 int tolerance; 4023 struct btrfs_device *srcdev; 4024 4025 if (dev_replace_is_ongoing && 4026 fs_info->dev_replace.cont_reading_from_srcdev_mode == 4027 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID) 4028 srcdev = fs_info->dev_replace.srcdev; 4029 else 4030 srcdev = NULL; 4031 4032 /* 4033 * try to avoid the drive that is the source drive for a 4034 * dev-replace procedure, only choose it if no other non-missing 4035 * mirror is available 4036 */ 4037 for (tolerance = 0; tolerance < 2; tolerance++) { 4038 if (map->stripes[optimal].dev->bdev && 4039 (tolerance || map->stripes[optimal].dev != srcdev)) 4040 return optimal; 4041 for (i = first; i < first + num; i++) { 4042 if (map->stripes[i].dev->bdev && 4043 (tolerance || map->stripes[i].dev != srcdev)) 4044 return i; 4045 } 4046 } 4047 4048 /* we couldn't find one that doesn't fail. Just return something 4049 * and the io error handling code will clean up eventually 4050 */ 4051 return optimal; 4052 } 4053 4054 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4055 u64 logical, u64 *length, 4056 struct btrfs_bio **bbio_ret, 4057 int mirror_num) 4058 { 4059 struct extent_map *em; 4060 struct map_lookup *map; 4061 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4062 struct extent_map_tree *em_tree = &map_tree->map_tree; 4063 u64 offset; 4064 u64 stripe_offset; 4065 u64 stripe_end_offset; 4066 u64 stripe_nr; 4067 u64 stripe_nr_orig; 4068 u64 stripe_nr_end; 4069 int stripe_index; 4070 int i; 4071 int ret = 0; 4072 int num_stripes; 4073 int max_errors = 0; 4074 struct btrfs_bio *bbio = NULL; 4075 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 4076 int dev_replace_is_ongoing = 0; 4077 int num_alloc_stripes; 4078 int patch_the_first_stripe_for_dev_replace = 0; 4079 u64 physical_to_patch_in_first_stripe = 0; 4080 4081 read_lock(&em_tree->lock); 4082 em = lookup_extent_mapping(em_tree, logical, *length); 4083 read_unlock(&em_tree->lock); 4084 4085 if (!em) { 4086 printk(KERN_CRIT "btrfs: unable to find logical %llu len %llu\n", 4087 (unsigned long long)logical, 4088 (unsigned long long)*length); 4089 BUG(); 4090 } 4091 4092 BUG_ON(em->start > logical || em->start + em->len < logical); 4093 map = (struct map_lookup *)em->bdev; 4094 offset = logical - em->start; 4095 4096 stripe_nr = offset; 4097 /* 4098 * stripe_nr counts the total number of stripes we have to stride 4099 * to get to this block 4100 */ 4101 do_div(stripe_nr, map->stripe_len); 4102 4103 stripe_offset = stripe_nr * map->stripe_len; 4104 BUG_ON(offset < stripe_offset); 4105 4106 /* stripe_offset is the offset of this block in its stripe*/ 4107 stripe_offset = offset - stripe_offset; 4108 4109 if (rw & REQ_DISCARD) 4110 *length = min_t(u64, em->len - offset, *length); 4111 else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { 4112 /* we limit the length of each bio to what fits in a stripe */ 4113 *length = min_t(u64, em->len - offset, 4114 map->stripe_len - stripe_offset); 4115 } else { 4116 *length = em->len - offset; 4117 } 4118 4119 if (!bbio_ret) 4120 goto out; 4121 4122 btrfs_dev_replace_lock(dev_replace); 4123 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace); 4124 if (!dev_replace_is_ongoing) 4125 btrfs_dev_replace_unlock(dev_replace); 4126 4127 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 && 4128 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) && 4129 dev_replace->tgtdev != NULL) { 4130 /* 4131 * in dev-replace case, for repair case (that's the only 4132 * case where the mirror is selected explicitly when 4133 * calling btrfs_map_block), blocks left of the left cursor 4134 * can also be read from the target drive. 4135 * For REQ_GET_READ_MIRRORS, the target drive is added as 4136 * the last one to the array of stripes. For READ, it also 4137 * needs to be supported using the same mirror number. 4138 * If the requested block is not left of the left cursor, 4139 * EIO is returned. This can happen because btrfs_num_copies() 4140 * returns one more in the dev-replace case. 4141 */ 4142 u64 tmp_length = *length; 4143 struct btrfs_bio *tmp_bbio = NULL; 4144 int tmp_num_stripes; 4145 u64 srcdev_devid = dev_replace->srcdev->devid; 4146 int index_srcdev = 0; 4147 int found = 0; 4148 u64 physical_of_found = 0; 4149 4150 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, 4151 logical, &tmp_length, &tmp_bbio, 0); 4152 if (ret) { 4153 WARN_ON(tmp_bbio != NULL); 4154 goto out; 4155 } 4156 4157 tmp_num_stripes = tmp_bbio->num_stripes; 4158 if (mirror_num > tmp_num_stripes) { 4159 /* 4160 * REQ_GET_READ_MIRRORS does not contain this 4161 * mirror, that means that the requested area 4162 * is not left of the left cursor 4163 */ 4164 ret = -EIO; 4165 kfree(tmp_bbio); 4166 goto out; 4167 } 4168 4169 /* 4170 * process the rest of the function using the mirror_num 4171 * of the source drive. Therefore look it up first. 4172 * At the end, patch the device pointer to the one of the 4173 * target drive. 4174 */ 4175 for (i = 0; i < tmp_num_stripes; i++) { 4176 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) { 4177 /* 4178 * In case of DUP, in order to keep it 4179 * simple, only add the mirror with the 4180 * lowest physical address 4181 */ 4182 if (found && 4183 physical_of_found <= 4184 tmp_bbio->stripes[i].physical) 4185 continue; 4186 index_srcdev = i; 4187 found = 1; 4188 physical_of_found = 4189 tmp_bbio->stripes[i].physical; 4190 } 4191 } 4192 4193 if (found) { 4194 mirror_num = index_srcdev + 1; 4195 patch_the_first_stripe_for_dev_replace = 1; 4196 physical_to_patch_in_first_stripe = physical_of_found; 4197 } else { 4198 WARN_ON(1); 4199 ret = -EIO; 4200 kfree(tmp_bbio); 4201 goto out; 4202 } 4203 4204 kfree(tmp_bbio); 4205 } else if (mirror_num > map->num_stripes) { 4206 mirror_num = 0; 4207 } 4208 4209 num_stripes = 1; 4210 stripe_index = 0; 4211 stripe_nr_orig = stripe_nr; 4212 stripe_nr_end = (offset + *length + map->stripe_len - 1) & 4213 (~(map->stripe_len - 1)); 4214 do_div(stripe_nr_end, map->stripe_len); 4215 stripe_end_offset = stripe_nr_end * map->stripe_len - 4216 (offset + *length); 4217 if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4218 if (rw & REQ_DISCARD) 4219 num_stripes = min_t(u64, map->num_stripes, 4220 stripe_nr_end - stripe_nr_orig); 4221 stripe_index = do_div(stripe_nr, map->num_stripes); 4222 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { 4223 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) 4224 num_stripes = map->num_stripes; 4225 else if (mirror_num) 4226 stripe_index = mirror_num - 1; 4227 else { 4228 stripe_index = find_live_mirror(fs_info, map, 0, 4229 map->num_stripes, 4230 current->pid % map->num_stripes, 4231 dev_replace_is_ongoing); 4232 mirror_num = stripe_index + 1; 4233 } 4234 4235 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { 4236 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) { 4237 num_stripes = map->num_stripes; 4238 } else if (mirror_num) { 4239 stripe_index = mirror_num - 1; 4240 } else { 4241 mirror_num = 1; 4242 } 4243 4244 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4245 int factor = map->num_stripes / map->sub_stripes; 4246 4247 stripe_index = do_div(stripe_nr, factor); 4248 stripe_index *= map->sub_stripes; 4249 4250 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) 4251 num_stripes = map->sub_stripes; 4252 else if (rw & REQ_DISCARD) 4253 num_stripes = min_t(u64, map->sub_stripes * 4254 (stripe_nr_end - stripe_nr_orig), 4255 map->num_stripes); 4256 else if (mirror_num) 4257 stripe_index += mirror_num - 1; 4258 else { 4259 int old_stripe_index = stripe_index; 4260 stripe_index = find_live_mirror(fs_info, map, 4261 stripe_index, 4262 map->sub_stripes, stripe_index + 4263 current->pid % map->sub_stripes, 4264 dev_replace_is_ongoing); 4265 mirror_num = stripe_index - old_stripe_index + 1; 4266 } 4267 } else { 4268 /* 4269 * after this do_div call, stripe_nr is the number of stripes 4270 * on this device we have to walk to find the data, and 4271 * stripe_index is the number of our device in the stripe array 4272 */ 4273 stripe_index = do_div(stripe_nr, map->num_stripes); 4274 mirror_num = stripe_index + 1; 4275 } 4276 BUG_ON(stripe_index >= map->num_stripes); 4277 4278 num_alloc_stripes = num_stripes; 4279 if (dev_replace_is_ongoing) { 4280 if (rw & (REQ_WRITE | REQ_DISCARD)) 4281 num_alloc_stripes <<= 1; 4282 if (rw & REQ_GET_READ_MIRRORS) 4283 num_alloc_stripes++; 4284 } 4285 bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS); 4286 if (!bbio) { 4287 ret = -ENOMEM; 4288 goto out; 4289 } 4290 atomic_set(&bbio->error, 0); 4291 4292 if (rw & REQ_DISCARD) { 4293 int factor = 0; 4294 int sub_stripes = 0; 4295 u64 stripes_per_dev = 0; 4296 u32 remaining_stripes = 0; 4297 u32 last_stripe = 0; 4298 4299 if (map->type & 4300 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { 4301 if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4302 sub_stripes = 1; 4303 else 4304 sub_stripes = map->sub_stripes; 4305 4306 factor = map->num_stripes / sub_stripes; 4307 stripes_per_dev = div_u64_rem(stripe_nr_end - 4308 stripe_nr_orig, 4309 factor, 4310 &remaining_stripes); 4311 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe); 4312 last_stripe *= sub_stripes; 4313 } 4314 4315 for (i = 0; i < num_stripes; i++) { 4316 bbio->stripes[i].physical = 4317 map->stripes[stripe_index].physical + 4318 stripe_offset + stripe_nr * map->stripe_len; 4319 bbio->stripes[i].dev = map->stripes[stripe_index].dev; 4320 4321 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | 4322 BTRFS_BLOCK_GROUP_RAID10)) { 4323 bbio->stripes[i].length = stripes_per_dev * 4324 map->stripe_len; 4325 4326 if (i / sub_stripes < remaining_stripes) 4327 bbio->stripes[i].length += 4328 map->stripe_len; 4329 4330 /* 4331 * Special for the first stripe and 4332 * the last stripe: 4333 * 4334 * |-------|...|-------| 4335 * |----------| 4336 * off end_off 4337 */ 4338 if (i < sub_stripes) 4339 bbio->stripes[i].length -= 4340 stripe_offset; 4341 4342 if (stripe_index >= last_stripe && 4343 stripe_index <= (last_stripe + 4344 sub_stripes - 1)) 4345 bbio->stripes[i].length -= 4346 stripe_end_offset; 4347 4348 if (i == sub_stripes - 1) 4349 stripe_offset = 0; 4350 } else 4351 bbio->stripes[i].length = *length; 4352 4353 stripe_index++; 4354 if (stripe_index == map->num_stripes) { 4355 /* This could only happen for RAID0/10 */ 4356 stripe_index = 0; 4357 stripe_nr++; 4358 } 4359 } 4360 } else { 4361 for (i = 0; i < num_stripes; i++) { 4362 bbio->stripes[i].physical = 4363 map->stripes[stripe_index].physical + 4364 stripe_offset + 4365 stripe_nr * map->stripe_len; 4366 bbio->stripes[i].dev = 4367 map->stripes[stripe_index].dev; 4368 stripe_index++; 4369 } 4370 } 4371 4372 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) { 4373 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | 4374 BTRFS_BLOCK_GROUP_RAID10 | 4375 BTRFS_BLOCK_GROUP_DUP)) { 4376 max_errors = 1; 4377 } 4378 } 4379 4380 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) && 4381 dev_replace->tgtdev != NULL) { 4382 int index_where_to_add; 4383 u64 srcdev_devid = dev_replace->srcdev->devid; 4384 4385 /* 4386 * duplicate the write operations while the dev replace 4387 * procedure is running. Since the copying of the old disk 4388 * to the new disk takes place at run time while the 4389 * filesystem is mounted writable, the regular write 4390 * operations to the old disk have to be duplicated to go 4391 * to the new disk as well. 4392 * Note that device->missing is handled by the caller, and 4393 * that the write to the old disk is already set up in the 4394 * stripes array. 4395 */ 4396 index_where_to_add = num_stripes; 4397 for (i = 0; i < num_stripes; i++) { 4398 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4399 /* write to new disk, too */ 4400 struct btrfs_bio_stripe *new = 4401 bbio->stripes + index_where_to_add; 4402 struct btrfs_bio_stripe *old = 4403 bbio->stripes + i; 4404 4405 new->physical = old->physical; 4406 new->length = old->length; 4407 new->dev = dev_replace->tgtdev; 4408 index_where_to_add++; 4409 max_errors++; 4410 } 4411 } 4412 num_stripes = index_where_to_add; 4413 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) && 4414 dev_replace->tgtdev != NULL) { 4415 u64 srcdev_devid = dev_replace->srcdev->devid; 4416 int index_srcdev = 0; 4417 int found = 0; 4418 u64 physical_of_found = 0; 4419 4420 /* 4421 * During the dev-replace procedure, the target drive can 4422 * also be used to read data in case it is needed to repair 4423 * a corrupt block elsewhere. This is possible if the 4424 * requested area is left of the left cursor. In this area, 4425 * the target drive is a full copy of the source drive. 4426 */ 4427 for (i = 0; i < num_stripes; i++) { 4428 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4429 /* 4430 * In case of DUP, in order to keep it 4431 * simple, only add the mirror with the 4432 * lowest physical address 4433 */ 4434 if (found && 4435 physical_of_found <= 4436 bbio->stripes[i].physical) 4437 continue; 4438 index_srcdev = i; 4439 found = 1; 4440 physical_of_found = bbio->stripes[i].physical; 4441 } 4442 } 4443 if (found) { 4444 u64 length = map->stripe_len; 4445 4446 if (physical_of_found + length <= 4447 dev_replace->cursor_left) { 4448 struct btrfs_bio_stripe *tgtdev_stripe = 4449 bbio->stripes + num_stripes; 4450 4451 tgtdev_stripe->physical = physical_of_found; 4452 tgtdev_stripe->length = 4453 bbio->stripes[index_srcdev].length; 4454 tgtdev_stripe->dev = dev_replace->tgtdev; 4455 4456 num_stripes++; 4457 } 4458 } 4459 } 4460 4461 *bbio_ret = bbio; 4462 bbio->num_stripes = num_stripes; 4463 bbio->max_errors = max_errors; 4464 bbio->mirror_num = mirror_num; 4465 4466 /* 4467 * this is the case that REQ_READ && dev_replace_is_ongoing && 4468 * mirror_num == num_stripes + 1 && dev_replace target drive is 4469 * available as a mirror 4470 */ 4471 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) { 4472 WARN_ON(num_stripes > 1); 4473 bbio->stripes[0].dev = dev_replace->tgtdev; 4474 bbio->stripes[0].physical = physical_to_patch_in_first_stripe; 4475 bbio->mirror_num = map->num_stripes + 1; 4476 } 4477 out: 4478 if (dev_replace_is_ongoing) 4479 btrfs_dev_replace_unlock(dev_replace); 4480 free_extent_map(em); 4481 return ret; 4482 } 4483 4484 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4485 u64 logical, u64 *length, 4486 struct btrfs_bio **bbio_ret, int mirror_num) 4487 { 4488 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret, 4489 mirror_num); 4490 } 4491 4492 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, 4493 u64 chunk_start, u64 physical, u64 devid, 4494 u64 **logical, int *naddrs, int *stripe_len) 4495 { 4496 struct extent_map_tree *em_tree = &map_tree->map_tree; 4497 struct extent_map *em; 4498 struct map_lookup *map; 4499 u64 *buf; 4500 u64 bytenr; 4501 u64 length; 4502 u64 stripe_nr; 4503 int i, j, nr = 0; 4504 4505 read_lock(&em_tree->lock); 4506 em = lookup_extent_mapping(em_tree, chunk_start, 1); 4507 read_unlock(&em_tree->lock); 4508 4509 BUG_ON(!em || em->start != chunk_start); 4510 map = (struct map_lookup *)em->bdev; 4511 4512 length = em->len; 4513 if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4514 do_div(length, map->num_stripes / map->sub_stripes); 4515 else if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4516 do_div(length, map->num_stripes); 4517 4518 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); 4519 BUG_ON(!buf); /* -ENOMEM */ 4520 4521 for (i = 0; i < map->num_stripes; i++) { 4522 if (devid && map->stripes[i].dev->devid != devid) 4523 continue; 4524 if (map->stripes[i].physical > physical || 4525 map->stripes[i].physical + length <= physical) 4526 continue; 4527 4528 stripe_nr = physical - map->stripes[i].physical; 4529 do_div(stripe_nr, map->stripe_len); 4530 4531 if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4532 stripe_nr = stripe_nr * map->num_stripes + i; 4533 do_div(stripe_nr, map->sub_stripes); 4534 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4535 stripe_nr = stripe_nr * map->num_stripes + i; 4536 } 4537 bytenr = chunk_start + stripe_nr * map->stripe_len; 4538 WARN_ON(nr >= map->num_stripes); 4539 for (j = 0; j < nr; j++) { 4540 if (buf[j] == bytenr) 4541 break; 4542 } 4543 if (j == nr) { 4544 WARN_ON(nr >= map->num_stripes); 4545 buf[nr++] = bytenr; 4546 } 4547 } 4548 4549 *logical = buf; 4550 *naddrs = nr; 4551 *stripe_len = map->stripe_len; 4552 4553 free_extent_map(em); 4554 return 0; 4555 } 4556 4557 static void *merge_stripe_index_into_bio_private(void *bi_private, 4558 unsigned int stripe_index) 4559 { 4560 /* 4561 * with single, dup, RAID0, RAID1 and RAID10, stripe_index is 4562 * at most 1. 4563 * The alternative solution (instead of stealing bits from the 4564 * pointer) would be to allocate an intermediate structure 4565 * that contains the old private pointer plus the stripe_index. 4566 */ 4567 BUG_ON((((uintptr_t)bi_private) & 3) != 0); 4568 BUG_ON(stripe_index > 3); 4569 return (void *)(((uintptr_t)bi_private) | stripe_index); 4570 } 4571 4572 static struct btrfs_bio *extract_bbio_from_bio_private(void *bi_private) 4573 { 4574 return (struct btrfs_bio *)(((uintptr_t)bi_private) & ~((uintptr_t)3)); 4575 } 4576 4577 static unsigned int extract_stripe_index_from_bio_private(void *bi_private) 4578 { 4579 return (unsigned int)((uintptr_t)bi_private) & 3; 4580 } 4581 4582 static void btrfs_end_bio(struct bio *bio, int err) 4583 { 4584 struct btrfs_bio *bbio = extract_bbio_from_bio_private(bio->bi_private); 4585 int is_orig_bio = 0; 4586 4587 if (err) { 4588 atomic_inc(&bbio->error); 4589 if (err == -EIO || err == -EREMOTEIO) { 4590 unsigned int stripe_index = 4591 extract_stripe_index_from_bio_private( 4592 bio->bi_private); 4593 struct btrfs_device *dev; 4594 4595 BUG_ON(stripe_index >= bbio->num_stripes); 4596 dev = bbio->stripes[stripe_index].dev; 4597 if (dev->bdev) { 4598 if (bio->bi_rw & WRITE) 4599 btrfs_dev_stat_inc(dev, 4600 BTRFS_DEV_STAT_WRITE_ERRS); 4601 else 4602 btrfs_dev_stat_inc(dev, 4603 BTRFS_DEV_STAT_READ_ERRS); 4604 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH) 4605 btrfs_dev_stat_inc(dev, 4606 BTRFS_DEV_STAT_FLUSH_ERRS); 4607 btrfs_dev_stat_print_on_error(dev); 4608 } 4609 } 4610 } 4611 4612 if (bio == bbio->orig_bio) 4613 is_orig_bio = 1; 4614 4615 if (atomic_dec_and_test(&bbio->stripes_pending)) { 4616 if (!is_orig_bio) { 4617 bio_put(bio); 4618 bio = bbio->orig_bio; 4619 } 4620 bio->bi_private = bbio->private; 4621 bio->bi_end_io = bbio->end_io; 4622 bio->bi_bdev = (struct block_device *) 4623 (unsigned long)bbio->mirror_num; 4624 /* only send an error to the higher layers if it is 4625 * beyond the tolerance of the multi-bio 4626 */ 4627 if (atomic_read(&bbio->error) > bbio->max_errors) { 4628 err = -EIO; 4629 } else { 4630 /* 4631 * this bio is actually up to date, we didn't 4632 * go over the max number of errors 4633 */ 4634 set_bit(BIO_UPTODATE, &bio->bi_flags); 4635 err = 0; 4636 } 4637 kfree(bbio); 4638 4639 bio_endio(bio, err); 4640 } else if (!is_orig_bio) { 4641 bio_put(bio); 4642 } 4643 } 4644 4645 struct async_sched { 4646 struct bio *bio; 4647 int rw; 4648 struct btrfs_fs_info *info; 4649 struct btrfs_work work; 4650 }; 4651 4652 /* 4653 * see run_scheduled_bios for a description of why bios are collected for 4654 * async submit. 4655 * 4656 * This will add one bio to the pending list for a device and make sure 4657 * the work struct is scheduled. 4658 */ 4659 static noinline void schedule_bio(struct btrfs_root *root, 4660 struct btrfs_device *device, 4661 int rw, struct bio *bio) 4662 { 4663 int should_queue = 1; 4664 struct btrfs_pending_bios *pending_bios; 4665 4666 /* don't bother with additional async steps for reads, right now */ 4667 if (!(rw & REQ_WRITE)) { 4668 bio_get(bio); 4669 btrfsic_submit_bio(rw, bio); 4670 bio_put(bio); 4671 return; 4672 } 4673 4674 /* 4675 * nr_async_bios allows us to reliably return congestion to the 4676 * higher layers. Otherwise, the async bio makes it appear we have 4677 * made progress against dirty pages when we've really just put it 4678 * on a queue for later 4679 */ 4680 atomic_inc(&root->fs_info->nr_async_bios); 4681 WARN_ON(bio->bi_next); 4682 bio->bi_next = NULL; 4683 bio->bi_rw |= rw; 4684 4685 spin_lock(&device->io_lock); 4686 if (bio->bi_rw & REQ_SYNC) 4687 pending_bios = &device->pending_sync_bios; 4688 else 4689 pending_bios = &device->pending_bios; 4690 4691 if (pending_bios->tail) 4692 pending_bios->tail->bi_next = bio; 4693 4694 pending_bios->tail = bio; 4695 if (!pending_bios->head) 4696 pending_bios->head = bio; 4697 if (device->running_pending) 4698 should_queue = 0; 4699 4700 spin_unlock(&device->io_lock); 4701 4702 if (should_queue) 4703 btrfs_queue_worker(&root->fs_info->submit_workers, 4704 &device->work); 4705 } 4706 4707 static int bio_size_ok(struct block_device *bdev, struct bio *bio, 4708 sector_t sector) 4709 { 4710 struct bio_vec *prev; 4711 struct request_queue *q = bdev_get_queue(bdev); 4712 unsigned short max_sectors = queue_max_sectors(q); 4713 struct bvec_merge_data bvm = { 4714 .bi_bdev = bdev, 4715 .bi_sector = sector, 4716 .bi_rw = bio->bi_rw, 4717 }; 4718 4719 if (bio->bi_vcnt == 0) { 4720 WARN_ON(1); 4721 return 1; 4722 } 4723 4724 prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; 4725 if ((bio->bi_size >> 9) > max_sectors) 4726 return 0; 4727 4728 if (!q->merge_bvec_fn) 4729 return 1; 4730 4731 bvm.bi_size = bio->bi_size - prev->bv_len; 4732 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) 4733 return 0; 4734 return 1; 4735 } 4736 4737 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 4738 struct bio *bio, u64 physical, int dev_nr, 4739 int rw, int async) 4740 { 4741 struct btrfs_device *dev = bbio->stripes[dev_nr].dev; 4742 4743 bio->bi_private = bbio; 4744 bio->bi_private = merge_stripe_index_into_bio_private( 4745 bio->bi_private, (unsigned int)dev_nr); 4746 bio->bi_end_io = btrfs_end_bio; 4747 bio->bi_sector = physical >> 9; 4748 #ifdef DEBUG 4749 { 4750 struct rcu_string *name; 4751 4752 rcu_read_lock(); 4753 name = rcu_dereference(dev->name); 4754 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu " 4755 "(%s id %llu), size=%u\n", rw, 4756 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, 4757 name->str, dev->devid, bio->bi_size); 4758 rcu_read_unlock(); 4759 } 4760 #endif 4761 bio->bi_bdev = dev->bdev; 4762 if (async) 4763 schedule_bio(root, dev, rw, bio); 4764 else 4765 btrfsic_submit_bio(rw, bio); 4766 } 4767 4768 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 4769 struct bio *first_bio, struct btrfs_device *dev, 4770 int dev_nr, int rw, int async) 4771 { 4772 struct bio_vec *bvec = first_bio->bi_io_vec; 4773 struct bio *bio; 4774 int nr_vecs = bio_get_nr_vecs(dev->bdev); 4775 u64 physical = bbio->stripes[dev_nr].physical; 4776 4777 again: 4778 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS); 4779 if (!bio) 4780 return -ENOMEM; 4781 4782 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) { 4783 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len, 4784 bvec->bv_offset) < bvec->bv_len) { 4785 u64 len = bio->bi_size; 4786 4787 atomic_inc(&bbio->stripes_pending); 4788 submit_stripe_bio(root, bbio, bio, physical, dev_nr, 4789 rw, async); 4790 physical += len; 4791 goto again; 4792 } 4793 bvec++; 4794 } 4795 4796 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async); 4797 return 0; 4798 } 4799 4800 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) 4801 { 4802 atomic_inc(&bbio->error); 4803 if (atomic_dec_and_test(&bbio->stripes_pending)) { 4804 bio->bi_private = bbio->private; 4805 bio->bi_end_io = bbio->end_io; 4806 bio->bi_bdev = (struct block_device *) 4807 (unsigned long)bbio->mirror_num; 4808 bio->bi_sector = logical >> 9; 4809 kfree(bbio); 4810 bio_endio(bio, -EIO); 4811 } 4812 } 4813 4814 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, 4815 int mirror_num, int async_submit) 4816 { 4817 struct btrfs_device *dev; 4818 struct bio *first_bio = bio; 4819 u64 logical = (u64)bio->bi_sector << 9; 4820 u64 length = 0; 4821 u64 map_length; 4822 int ret; 4823 int dev_nr = 0; 4824 int total_devs = 1; 4825 struct btrfs_bio *bbio = NULL; 4826 4827 length = bio->bi_size; 4828 map_length = length; 4829 4830 ret = btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio, 4831 mirror_num); 4832 if (ret) 4833 return ret; 4834 4835 total_devs = bbio->num_stripes; 4836 if (map_length < length) { 4837 printk(KERN_CRIT "btrfs: mapping failed logical %llu bio len %llu " 4838 "len %llu\n", (unsigned long long)logical, 4839 (unsigned long long)length, 4840 (unsigned long long)map_length); 4841 BUG(); 4842 } 4843 4844 bbio->orig_bio = first_bio; 4845 bbio->private = first_bio->bi_private; 4846 bbio->end_io = first_bio->bi_end_io; 4847 atomic_set(&bbio->stripes_pending, bbio->num_stripes); 4848 4849 while (dev_nr < total_devs) { 4850 dev = bbio->stripes[dev_nr].dev; 4851 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) { 4852 bbio_error(bbio, first_bio, logical); 4853 dev_nr++; 4854 continue; 4855 } 4856 4857 /* 4858 * Check and see if we're ok with this bio based on it's size 4859 * and offset with the given device. 4860 */ 4861 if (!bio_size_ok(dev->bdev, first_bio, 4862 bbio->stripes[dev_nr].physical >> 9)) { 4863 ret = breakup_stripe_bio(root, bbio, first_bio, dev, 4864 dev_nr, rw, async_submit); 4865 BUG_ON(ret); 4866 dev_nr++; 4867 continue; 4868 } 4869 4870 if (dev_nr < total_devs - 1) { 4871 bio = bio_clone(first_bio, GFP_NOFS); 4872 BUG_ON(!bio); /* -ENOMEM */ 4873 } else { 4874 bio = first_bio; 4875 } 4876 4877 submit_stripe_bio(root, bbio, bio, 4878 bbio->stripes[dev_nr].physical, dev_nr, rw, 4879 async_submit); 4880 dev_nr++; 4881 } 4882 return 0; 4883 } 4884 4885 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, 4886 u8 *uuid, u8 *fsid) 4887 { 4888 struct btrfs_device *device; 4889 struct btrfs_fs_devices *cur_devices; 4890 4891 cur_devices = fs_info->fs_devices; 4892 while (cur_devices) { 4893 if (!fsid || 4894 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 4895 device = __find_device(&cur_devices->devices, 4896 devid, uuid); 4897 if (device) 4898 return device; 4899 } 4900 cur_devices = cur_devices->seed; 4901 } 4902 return NULL; 4903 } 4904 4905 static struct btrfs_device *add_missing_dev(struct btrfs_root *root, 4906 u64 devid, u8 *dev_uuid) 4907 { 4908 struct btrfs_device *device; 4909 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 4910 4911 device = kzalloc(sizeof(*device), GFP_NOFS); 4912 if (!device) 4913 return NULL; 4914 list_add(&device->dev_list, 4915 &fs_devices->devices); 4916 device->dev_root = root->fs_info->dev_root; 4917 device->devid = devid; 4918 device->work.func = pending_bios_fn; 4919 device->fs_devices = fs_devices; 4920 device->missing = 1; 4921 fs_devices->num_devices++; 4922 fs_devices->missing_devices++; 4923 spin_lock_init(&device->io_lock); 4924 INIT_LIST_HEAD(&device->dev_alloc_list); 4925 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE); 4926 return device; 4927 } 4928 4929 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, 4930 struct extent_buffer *leaf, 4931 struct btrfs_chunk *chunk) 4932 { 4933 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 4934 struct map_lookup *map; 4935 struct extent_map *em; 4936 u64 logical; 4937 u64 length; 4938 u64 devid; 4939 u8 uuid[BTRFS_UUID_SIZE]; 4940 int num_stripes; 4941 int ret; 4942 int i; 4943 4944 logical = key->offset; 4945 length = btrfs_chunk_length(leaf, chunk); 4946 4947 read_lock(&map_tree->map_tree.lock); 4948 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1); 4949 read_unlock(&map_tree->map_tree.lock); 4950 4951 /* already mapped? */ 4952 if (em && em->start <= logical && em->start + em->len > logical) { 4953 free_extent_map(em); 4954 return 0; 4955 } else if (em) { 4956 free_extent_map(em); 4957 } 4958 4959 em = alloc_extent_map(); 4960 if (!em) 4961 return -ENOMEM; 4962 num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 4963 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 4964 if (!map) { 4965 free_extent_map(em); 4966 return -ENOMEM; 4967 } 4968 4969 em->bdev = (struct block_device *)map; 4970 em->start = logical; 4971 em->len = length; 4972 em->orig_start = 0; 4973 em->block_start = 0; 4974 em->block_len = em->len; 4975 4976 map->num_stripes = num_stripes; 4977 map->io_width = btrfs_chunk_io_width(leaf, chunk); 4978 map->io_align = btrfs_chunk_io_align(leaf, chunk); 4979 map->sector_size = btrfs_chunk_sector_size(leaf, chunk); 4980 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); 4981 map->type = btrfs_chunk_type(leaf, chunk); 4982 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); 4983 for (i = 0; i < num_stripes; i++) { 4984 map->stripes[i].physical = 4985 btrfs_stripe_offset_nr(leaf, chunk, i); 4986 devid = btrfs_stripe_devid_nr(leaf, chunk, i); 4987 read_extent_buffer(leaf, uuid, (unsigned long) 4988 btrfs_stripe_dev_uuid_nr(chunk, i), 4989 BTRFS_UUID_SIZE); 4990 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid, 4991 uuid, NULL); 4992 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) { 4993 kfree(map); 4994 free_extent_map(em); 4995 return -EIO; 4996 } 4997 if (!map->stripes[i].dev) { 4998 map->stripes[i].dev = 4999 add_missing_dev(root, devid, uuid); 5000 if (!map->stripes[i].dev) { 5001 kfree(map); 5002 free_extent_map(em); 5003 return -EIO; 5004 } 5005 } 5006 map->stripes[i].dev->in_fs_metadata = 1; 5007 } 5008 5009 write_lock(&map_tree->map_tree.lock); 5010 ret = add_extent_mapping(&map_tree->map_tree, em); 5011 write_unlock(&map_tree->map_tree.lock); 5012 BUG_ON(ret); /* Tree corruption */ 5013 free_extent_map(em); 5014 5015 return 0; 5016 } 5017 5018 static void fill_device_from_item(struct extent_buffer *leaf, 5019 struct btrfs_dev_item *dev_item, 5020 struct btrfs_device *device) 5021 { 5022 unsigned long ptr; 5023 5024 device->devid = btrfs_device_id(leaf, dev_item); 5025 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); 5026 device->total_bytes = device->disk_total_bytes; 5027 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); 5028 device->type = btrfs_device_type(leaf, dev_item); 5029 device->io_align = btrfs_device_io_align(leaf, dev_item); 5030 device->io_width = btrfs_device_io_width(leaf, dev_item); 5031 device->sector_size = btrfs_device_sector_size(leaf, dev_item); 5032 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); 5033 device->is_tgtdev_for_dev_replace = 0; 5034 5035 ptr = (unsigned long)btrfs_device_uuid(dev_item); 5036 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 5037 } 5038 5039 static int open_seed_devices(struct btrfs_root *root, u8 *fsid) 5040 { 5041 struct btrfs_fs_devices *fs_devices; 5042 int ret; 5043 5044 BUG_ON(!mutex_is_locked(&uuid_mutex)); 5045 5046 fs_devices = root->fs_info->fs_devices->seed; 5047 while (fs_devices) { 5048 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5049 ret = 0; 5050 goto out; 5051 } 5052 fs_devices = fs_devices->seed; 5053 } 5054 5055 fs_devices = find_fsid(fsid); 5056 if (!fs_devices) { 5057 ret = -ENOENT; 5058 goto out; 5059 } 5060 5061 fs_devices = clone_fs_devices(fs_devices); 5062 if (IS_ERR(fs_devices)) { 5063 ret = PTR_ERR(fs_devices); 5064 goto out; 5065 } 5066 5067 ret = __btrfs_open_devices(fs_devices, FMODE_READ, 5068 root->fs_info->bdev_holder); 5069 if (ret) { 5070 free_fs_devices(fs_devices); 5071 goto out; 5072 } 5073 5074 if (!fs_devices->seeding) { 5075 __btrfs_close_devices(fs_devices); 5076 free_fs_devices(fs_devices); 5077 ret = -EINVAL; 5078 goto out; 5079 } 5080 5081 fs_devices->seed = root->fs_info->fs_devices->seed; 5082 root->fs_info->fs_devices->seed = fs_devices; 5083 out: 5084 return ret; 5085 } 5086 5087 static int read_one_dev(struct btrfs_root *root, 5088 struct extent_buffer *leaf, 5089 struct btrfs_dev_item *dev_item) 5090 { 5091 struct btrfs_device *device; 5092 u64 devid; 5093 int ret; 5094 u8 fs_uuid[BTRFS_UUID_SIZE]; 5095 u8 dev_uuid[BTRFS_UUID_SIZE]; 5096 5097 devid = btrfs_device_id(leaf, dev_item); 5098 read_extent_buffer(leaf, dev_uuid, 5099 (unsigned long)btrfs_device_uuid(dev_item), 5100 BTRFS_UUID_SIZE); 5101 read_extent_buffer(leaf, fs_uuid, 5102 (unsigned long)btrfs_device_fsid(dev_item), 5103 BTRFS_UUID_SIZE); 5104 5105 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) { 5106 ret = open_seed_devices(root, fs_uuid); 5107 if (ret && !btrfs_test_opt(root, DEGRADED)) 5108 return ret; 5109 } 5110 5111 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid); 5112 if (!device || !device->bdev) { 5113 if (!btrfs_test_opt(root, DEGRADED)) 5114 return -EIO; 5115 5116 if (!device) { 5117 printk(KERN_WARNING "warning devid %llu missing\n", 5118 (unsigned long long)devid); 5119 device = add_missing_dev(root, devid, dev_uuid); 5120 if (!device) 5121 return -ENOMEM; 5122 } else if (!device->missing) { 5123 /* 5124 * this happens when a device that was properly setup 5125 * in the device info lists suddenly goes bad. 5126 * device->bdev is NULL, and so we have to set 5127 * device->missing to one here 5128 */ 5129 root->fs_info->fs_devices->missing_devices++; 5130 device->missing = 1; 5131 } 5132 } 5133 5134 if (device->fs_devices != root->fs_info->fs_devices) { 5135 BUG_ON(device->writeable); 5136 if (device->generation != 5137 btrfs_device_generation(leaf, dev_item)) 5138 return -EINVAL; 5139 } 5140 5141 fill_device_from_item(leaf, dev_item, device); 5142 device->dev_root = root->fs_info->dev_root; 5143 device->in_fs_metadata = 1; 5144 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 5145 device->fs_devices->total_rw_bytes += device->total_bytes; 5146 spin_lock(&root->fs_info->free_chunk_lock); 5147 root->fs_info->free_chunk_space += device->total_bytes - 5148 device->bytes_used; 5149 spin_unlock(&root->fs_info->free_chunk_lock); 5150 } 5151 ret = 0; 5152 return ret; 5153 } 5154 5155 int btrfs_read_sys_array(struct btrfs_root *root) 5156 { 5157 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 5158 struct extent_buffer *sb; 5159 struct btrfs_disk_key *disk_key; 5160 struct btrfs_chunk *chunk; 5161 u8 *ptr; 5162 unsigned long sb_ptr; 5163 int ret = 0; 5164 u32 num_stripes; 5165 u32 array_size; 5166 u32 len = 0; 5167 u32 cur; 5168 struct btrfs_key key; 5169 5170 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET, 5171 BTRFS_SUPER_INFO_SIZE); 5172 if (!sb) 5173 return -ENOMEM; 5174 btrfs_set_buffer_uptodate(sb); 5175 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); 5176 /* 5177 * The sb extent buffer is artifical and just used to read the system array. 5178 * btrfs_set_buffer_uptodate() call does not properly mark all it's 5179 * pages up-to-date when the page is larger: extent does not cover the 5180 * whole page and consequently check_page_uptodate does not find all 5181 * the page's extents up-to-date (the hole beyond sb), 5182 * write_extent_buffer then triggers a WARN_ON. 5183 * 5184 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle, 5185 * but sb spans only this function. Add an explicit SetPageUptodate call 5186 * to silence the warning eg. on PowerPC 64. 5187 */ 5188 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE) 5189 SetPageUptodate(sb->pages[0]); 5190 5191 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); 5192 array_size = btrfs_super_sys_array_size(super_copy); 5193 5194 ptr = super_copy->sys_chunk_array; 5195 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array); 5196 cur = 0; 5197 5198 while (cur < array_size) { 5199 disk_key = (struct btrfs_disk_key *)ptr; 5200 btrfs_disk_key_to_cpu(&key, disk_key); 5201 5202 len = sizeof(*disk_key); ptr += len; 5203 sb_ptr += len; 5204 cur += len; 5205 5206 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 5207 chunk = (struct btrfs_chunk *)sb_ptr; 5208 ret = read_one_chunk(root, &key, sb, chunk); 5209 if (ret) 5210 break; 5211 num_stripes = btrfs_chunk_num_stripes(sb, chunk); 5212 len = btrfs_chunk_item_size(num_stripes); 5213 } else { 5214 ret = -EIO; 5215 break; 5216 } 5217 ptr += len; 5218 sb_ptr += len; 5219 cur += len; 5220 } 5221 free_extent_buffer(sb); 5222 return ret; 5223 } 5224 5225 int btrfs_read_chunk_tree(struct btrfs_root *root) 5226 { 5227 struct btrfs_path *path; 5228 struct extent_buffer *leaf; 5229 struct btrfs_key key; 5230 struct btrfs_key found_key; 5231 int ret; 5232 int slot; 5233 5234 root = root->fs_info->chunk_root; 5235 5236 path = btrfs_alloc_path(); 5237 if (!path) 5238 return -ENOMEM; 5239 5240 mutex_lock(&uuid_mutex); 5241 lock_chunks(root); 5242 5243 /* first we search for all of the device items, and then we 5244 * read in all of the chunk items. This way we can create chunk 5245 * mappings that reference all of the devices that are afound 5246 */ 5247 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 5248 key.offset = 0; 5249 key.type = 0; 5250 again: 5251 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5252 if (ret < 0) 5253 goto error; 5254 while (1) { 5255 leaf = path->nodes[0]; 5256 slot = path->slots[0]; 5257 if (slot >= btrfs_header_nritems(leaf)) { 5258 ret = btrfs_next_leaf(root, path); 5259 if (ret == 0) 5260 continue; 5261 if (ret < 0) 5262 goto error; 5263 break; 5264 } 5265 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5266 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5267 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID) 5268 break; 5269 if (found_key.type == BTRFS_DEV_ITEM_KEY) { 5270 struct btrfs_dev_item *dev_item; 5271 dev_item = btrfs_item_ptr(leaf, slot, 5272 struct btrfs_dev_item); 5273 ret = read_one_dev(root, leaf, dev_item); 5274 if (ret) 5275 goto error; 5276 } 5277 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { 5278 struct btrfs_chunk *chunk; 5279 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 5280 ret = read_one_chunk(root, &found_key, leaf, chunk); 5281 if (ret) 5282 goto error; 5283 } 5284 path->slots[0]++; 5285 } 5286 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5287 key.objectid = 0; 5288 btrfs_release_path(path); 5289 goto again; 5290 } 5291 ret = 0; 5292 error: 5293 unlock_chunks(root); 5294 mutex_unlock(&uuid_mutex); 5295 5296 btrfs_free_path(path); 5297 return ret; 5298 } 5299 5300 static void __btrfs_reset_dev_stats(struct btrfs_device *dev) 5301 { 5302 int i; 5303 5304 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5305 btrfs_dev_stat_reset(dev, i); 5306 } 5307 5308 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) 5309 { 5310 struct btrfs_key key; 5311 struct btrfs_key found_key; 5312 struct btrfs_root *dev_root = fs_info->dev_root; 5313 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5314 struct extent_buffer *eb; 5315 int slot; 5316 int ret = 0; 5317 struct btrfs_device *device; 5318 struct btrfs_path *path = NULL; 5319 int i; 5320 5321 path = btrfs_alloc_path(); 5322 if (!path) { 5323 ret = -ENOMEM; 5324 goto out; 5325 } 5326 5327 mutex_lock(&fs_devices->device_list_mutex); 5328 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5329 int item_size; 5330 struct btrfs_dev_stats_item *ptr; 5331 5332 key.objectid = 0; 5333 key.type = BTRFS_DEV_STATS_KEY; 5334 key.offset = device->devid; 5335 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 5336 if (ret) { 5337 __btrfs_reset_dev_stats(device); 5338 device->dev_stats_valid = 1; 5339 btrfs_release_path(path); 5340 continue; 5341 } 5342 slot = path->slots[0]; 5343 eb = path->nodes[0]; 5344 btrfs_item_key_to_cpu(eb, &found_key, slot); 5345 item_size = btrfs_item_size_nr(eb, slot); 5346 5347 ptr = btrfs_item_ptr(eb, slot, 5348 struct btrfs_dev_stats_item); 5349 5350 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5351 if (item_size >= (1 + i) * sizeof(__le64)) 5352 btrfs_dev_stat_set(device, i, 5353 btrfs_dev_stats_value(eb, ptr, i)); 5354 else 5355 btrfs_dev_stat_reset(device, i); 5356 } 5357 5358 device->dev_stats_valid = 1; 5359 btrfs_dev_stat_print_on_load(device); 5360 btrfs_release_path(path); 5361 } 5362 mutex_unlock(&fs_devices->device_list_mutex); 5363 5364 out: 5365 btrfs_free_path(path); 5366 return ret < 0 ? ret : 0; 5367 } 5368 5369 static int update_dev_stat_item(struct btrfs_trans_handle *trans, 5370 struct btrfs_root *dev_root, 5371 struct btrfs_device *device) 5372 { 5373 struct btrfs_path *path; 5374 struct btrfs_key key; 5375 struct extent_buffer *eb; 5376 struct btrfs_dev_stats_item *ptr; 5377 int ret; 5378 int i; 5379 5380 key.objectid = 0; 5381 key.type = BTRFS_DEV_STATS_KEY; 5382 key.offset = device->devid; 5383 5384 path = btrfs_alloc_path(); 5385 BUG_ON(!path); 5386 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 5387 if (ret < 0) { 5388 printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n", 5389 ret, rcu_str_deref(device->name)); 5390 goto out; 5391 } 5392 5393 if (ret == 0 && 5394 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 5395 /* need to delete old one and insert a new one */ 5396 ret = btrfs_del_item(trans, dev_root, path); 5397 if (ret != 0) { 5398 printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n", 5399 rcu_str_deref(device->name), ret); 5400 goto out; 5401 } 5402 ret = 1; 5403 } 5404 5405 if (ret == 1) { 5406 /* need to insert a new item */ 5407 btrfs_release_path(path); 5408 ret = btrfs_insert_empty_item(trans, dev_root, path, 5409 &key, sizeof(*ptr)); 5410 if (ret < 0) { 5411 printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n", 5412 rcu_str_deref(device->name), ret); 5413 goto out; 5414 } 5415 } 5416 5417 eb = path->nodes[0]; 5418 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); 5419 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5420 btrfs_set_dev_stats_value(eb, ptr, i, 5421 btrfs_dev_stat_read(device, i)); 5422 btrfs_mark_buffer_dirty(eb); 5423 5424 out: 5425 btrfs_free_path(path); 5426 return ret; 5427 } 5428 5429 /* 5430 * called from commit_transaction. Writes all changed device stats to disk. 5431 */ 5432 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, 5433 struct btrfs_fs_info *fs_info) 5434 { 5435 struct btrfs_root *dev_root = fs_info->dev_root; 5436 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5437 struct btrfs_device *device; 5438 int ret = 0; 5439 5440 mutex_lock(&fs_devices->device_list_mutex); 5441 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5442 if (!device->dev_stats_valid || !device->dev_stats_dirty) 5443 continue; 5444 5445 ret = update_dev_stat_item(trans, dev_root, device); 5446 if (!ret) 5447 device->dev_stats_dirty = 0; 5448 } 5449 mutex_unlock(&fs_devices->device_list_mutex); 5450 5451 return ret; 5452 } 5453 5454 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) 5455 { 5456 btrfs_dev_stat_inc(dev, index); 5457 btrfs_dev_stat_print_on_error(dev); 5458 } 5459 5460 void btrfs_dev_stat_print_on_error(struct btrfs_device *dev) 5461 { 5462 if (!dev->dev_stats_valid) 5463 return; 5464 printk_ratelimited_in_rcu(KERN_ERR 5465 "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5466 rcu_str_deref(dev->name), 5467 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5468 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5469 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5470 btrfs_dev_stat_read(dev, 5471 BTRFS_DEV_STAT_CORRUPTION_ERRS), 5472 btrfs_dev_stat_read(dev, 5473 BTRFS_DEV_STAT_GENERATION_ERRS)); 5474 } 5475 5476 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) 5477 { 5478 int i; 5479 5480 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5481 if (btrfs_dev_stat_read(dev, i) != 0) 5482 break; 5483 if (i == BTRFS_DEV_STAT_VALUES_MAX) 5484 return; /* all values == 0, suppress message */ 5485 5486 printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5487 rcu_str_deref(dev->name), 5488 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5489 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5490 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5491 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), 5492 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); 5493 } 5494 5495 int btrfs_get_dev_stats(struct btrfs_root *root, 5496 struct btrfs_ioctl_get_dev_stats *stats) 5497 { 5498 struct btrfs_device *dev; 5499 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5500 int i; 5501 5502 mutex_lock(&fs_devices->device_list_mutex); 5503 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL); 5504 mutex_unlock(&fs_devices->device_list_mutex); 5505 5506 if (!dev) { 5507 printk(KERN_WARNING 5508 "btrfs: get dev_stats failed, device not found\n"); 5509 return -ENODEV; 5510 } else if (!dev->dev_stats_valid) { 5511 printk(KERN_WARNING 5512 "btrfs: get dev_stats failed, not yet valid\n"); 5513 return -ENODEV; 5514 } else if (stats->flags & BTRFS_DEV_STATS_RESET) { 5515 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5516 if (stats->nr_items > i) 5517 stats->values[i] = 5518 btrfs_dev_stat_read_and_reset(dev, i); 5519 else 5520 btrfs_dev_stat_reset(dev, i); 5521 } 5522 } else { 5523 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5524 if (stats->nr_items > i) 5525 stats->values[i] = btrfs_dev_stat_read(dev, i); 5526 } 5527 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) 5528 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; 5529 return 0; 5530 } 5531 5532 int btrfs_scratch_superblock(struct btrfs_device *device) 5533 { 5534 struct buffer_head *bh; 5535 struct btrfs_super_block *disk_super; 5536 5537 bh = btrfs_read_dev_super(device->bdev); 5538 if (!bh) 5539 return -EINVAL; 5540 disk_super = (struct btrfs_super_block *)bh->b_data; 5541 5542 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 5543 set_buffer_dirty(bh); 5544 sync_dirty_buffer(bh); 5545 brelse(bh); 5546 5547 return 0; 5548 } 5549