1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 #include <linux/sched.h> 19 #include <linux/bio.h> 20 #include <linux/slab.h> 21 #include <linux/buffer_head.h> 22 #include <linux/blkdev.h> 23 #include <linux/random.h> 24 #include <linux/iocontext.h> 25 #include <linux/capability.h> 26 #include <linux/ratelimit.h> 27 #include <linux/kthread.h> 28 #include <linux/raid/pq.h> 29 #include <asm/div64.h> 30 #include "compat.h" 31 #include "ctree.h" 32 #include "extent_map.h" 33 #include "disk-io.h" 34 #include "transaction.h" 35 #include "print-tree.h" 36 #include "volumes.h" 37 #include "raid56.h" 38 #include "async-thread.h" 39 #include "check-integrity.h" 40 #include "rcu-string.h" 41 #include "math.h" 42 #include "dev-replace.h" 43 44 static int init_first_rw_device(struct btrfs_trans_handle *trans, 45 struct btrfs_root *root, 46 struct btrfs_device *device); 47 static int btrfs_relocate_sys_chunks(struct btrfs_root *root); 48 static void __btrfs_reset_dev_stats(struct btrfs_device *dev); 49 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev); 50 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); 51 52 static DEFINE_MUTEX(uuid_mutex); 53 static LIST_HEAD(fs_uuids); 54 55 static void lock_chunks(struct btrfs_root *root) 56 { 57 mutex_lock(&root->fs_info->chunk_mutex); 58 } 59 60 static void unlock_chunks(struct btrfs_root *root) 61 { 62 mutex_unlock(&root->fs_info->chunk_mutex); 63 } 64 65 static void free_fs_devices(struct btrfs_fs_devices *fs_devices) 66 { 67 struct btrfs_device *device; 68 WARN_ON(fs_devices->opened); 69 while (!list_empty(&fs_devices->devices)) { 70 device = list_entry(fs_devices->devices.next, 71 struct btrfs_device, dev_list); 72 list_del(&device->dev_list); 73 rcu_string_free(device->name); 74 kfree(device); 75 } 76 kfree(fs_devices); 77 } 78 79 static void btrfs_kobject_uevent(struct block_device *bdev, 80 enum kobject_action action) 81 { 82 int ret; 83 84 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action); 85 if (ret) 86 pr_warn("Sending event '%d' to kobject: '%s' (%p): failed\n", 87 action, 88 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj), 89 &disk_to_dev(bdev->bd_disk)->kobj); 90 } 91 92 void btrfs_cleanup_fs_uuids(void) 93 { 94 struct btrfs_fs_devices *fs_devices; 95 96 while (!list_empty(&fs_uuids)) { 97 fs_devices = list_entry(fs_uuids.next, 98 struct btrfs_fs_devices, list); 99 list_del(&fs_devices->list); 100 free_fs_devices(fs_devices); 101 } 102 } 103 104 static noinline struct btrfs_device *__find_device(struct list_head *head, 105 u64 devid, u8 *uuid) 106 { 107 struct btrfs_device *dev; 108 109 list_for_each_entry(dev, head, dev_list) { 110 if (dev->devid == devid && 111 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { 112 return dev; 113 } 114 } 115 return NULL; 116 } 117 118 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid) 119 { 120 struct btrfs_fs_devices *fs_devices; 121 122 list_for_each_entry(fs_devices, &fs_uuids, list) { 123 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0) 124 return fs_devices; 125 } 126 return NULL; 127 } 128 129 static int 130 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder, 131 int flush, struct block_device **bdev, 132 struct buffer_head **bh) 133 { 134 int ret; 135 136 *bdev = blkdev_get_by_path(device_path, flags, holder); 137 138 if (IS_ERR(*bdev)) { 139 ret = PTR_ERR(*bdev); 140 printk(KERN_INFO "btrfs: open %s failed\n", device_path); 141 goto error; 142 } 143 144 if (flush) 145 filemap_write_and_wait((*bdev)->bd_inode->i_mapping); 146 ret = set_blocksize(*bdev, 4096); 147 if (ret) { 148 blkdev_put(*bdev, flags); 149 goto error; 150 } 151 invalidate_bdev(*bdev); 152 *bh = btrfs_read_dev_super(*bdev); 153 if (!*bh) { 154 ret = -EINVAL; 155 blkdev_put(*bdev, flags); 156 goto error; 157 } 158 159 return 0; 160 161 error: 162 *bdev = NULL; 163 *bh = NULL; 164 return ret; 165 } 166 167 static void requeue_list(struct btrfs_pending_bios *pending_bios, 168 struct bio *head, struct bio *tail) 169 { 170 171 struct bio *old_head; 172 173 old_head = pending_bios->head; 174 pending_bios->head = head; 175 if (pending_bios->tail) 176 tail->bi_next = old_head; 177 else 178 pending_bios->tail = tail; 179 } 180 181 /* 182 * we try to collect pending bios for a device so we don't get a large 183 * number of procs sending bios down to the same device. This greatly 184 * improves the schedulers ability to collect and merge the bios. 185 * 186 * But, it also turns into a long list of bios to process and that is sure 187 * to eventually make the worker thread block. The solution here is to 188 * make some progress and then put this work struct back at the end of 189 * the list if the block device is congested. This way, multiple devices 190 * can make progress from a single worker thread. 191 */ 192 static noinline void run_scheduled_bios(struct btrfs_device *device) 193 { 194 struct bio *pending; 195 struct backing_dev_info *bdi; 196 struct btrfs_fs_info *fs_info; 197 struct btrfs_pending_bios *pending_bios; 198 struct bio *tail; 199 struct bio *cur; 200 int again = 0; 201 unsigned long num_run; 202 unsigned long batch_run = 0; 203 unsigned long limit; 204 unsigned long last_waited = 0; 205 int force_reg = 0; 206 int sync_pending = 0; 207 struct blk_plug plug; 208 209 /* 210 * this function runs all the bios we've collected for 211 * a particular device. We don't want to wander off to 212 * another device without first sending all of these down. 213 * So, setup a plug here and finish it off before we return 214 */ 215 blk_start_plug(&plug); 216 217 bdi = blk_get_backing_dev_info(device->bdev); 218 fs_info = device->dev_root->fs_info; 219 limit = btrfs_async_submit_limit(fs_info); 220 limit = limit * 2 / 3; 221 222 loop: 223 spin_lock(&device->io_lock); 224 225 loop_lock: 226 num_run = 0; 227 228 /* take all the bios off the list at once and process them 229 * later on (without the lock held). But, remember the 230 * tail and other pointers so the bios can be properly reinserted 231 * into the list if we hit congestion 232 */ 233 if (!force_reg && device->pending_sync_bios.head) { 234 pending_bios = &device->pending_sync_bios; 235 force_reg = 1; 236 } else { 237 pending_bios = &device->pending_bios; 238 force_reg = 0; 239 } 240 241 pending = pending_bios->head; 242 tail = pending_bios->tail; 243 WARN_ON(pending && !tail); 244 245 /* 246 * if pending was null this time around, no bios need processing 247 * at all and we can stop. Otherwise it'll loop back up again 248 * and do an additional check so no bios are missed. 249 * 250 * device->running_pending is used to synchronize with the 251 * schedule_bio code. 252 */ 253 if (device->pending_sync_bios.head == NULL && 254 device->pending_bios.head == NULL) { 255 again = 0; 256 device->running_pending = 0; 257 } else { 258 again = 1; 259 device->running_pending = 1; 260 } 261 262 pending_bios->head = NULL; 263 pending_bios->tail = NULL; 264 265 spin_unlock(&device->io_lock); 266 267 while (pending) { 268 269 rmb(); 270 /* we want to work on both lists, but do more bios on the 271 * sync list than the regular list 272 */ 273 if ((num_run > 32 && 274 pending_bios != &device->pending_sync_bios && 275 device->pending_sync_bios.head) || 276 (num_run > 64 && pending_bios == &device->pending_sync_bios && 277 device->pending_bios.head)) { 278 spin_lock(&device->io_lock); 279 requeue_list(pending_bios, pending, tail); 280 goto loop_lock; 281 } 282 283 cur = pending; 284 pending = pending->bi_next; 285 cur->bi_next = NULL; 286 287 if (atomic_dec_return(&fs_info->nr_async_bios) < limit && 288 waitqueue_active(&fs_info->async_submit_wait)) 289 wake_up(&fs_info->async_submit_wait); 290 291 BUG_ON(atomic_read(&cur->bi_cnt) == 0); 292 293 /* 294 * if we're doing the sync list, record that our 295 * plug has some sync requests on it 296 * 297 * If we're doing the regular list and there are 298 * sync requests sitting around, unplug before 299 * we add more 300 */ 301 if (pending_bios == &device->pending_sync_bios) { 302 sync_pending = 1; 303 } else if (sync_pending) { 304 blk_finish_plug(&plug); 305 blk_start_plug(&plug); 306 sync_pending = 0; 307 } 308 309 btrfsic_submit_bio(cur->bi_rw, cur); 310 num_run++; 311 batch_run++; 312 if (need_resched()) 313 cond_resched(); 314 315 /* 316 * we made progress, there is more work to do and the bdi 317 * is now congested. Back off and let other work structs 318 * run instead 319 */ 320 if (pending && bdi_write_congested(bdi) && batch_run > 8 && 321 fs_info->fs_devices->open_devices > 1) { 322 struct io_context *ioc; 323 324 ioc = current->io_context; 325 326 /* 327 * the main goal here is that we don't want to 328 * block if we're going to be able to submit 329 * more requests without blocking. 330 * 331 * This code does two great things, it pokes into 332 * the elevator code from a filesystem _and_ 333 * it makes assumptions about how batching works. 334 */ 335 if (ioc && ioc->nr_batch_requests > 0 && 336 time_before(jiffies, ioc->last_waited + HZ/50UL) && 337 (last_waited == 0 || 338 ioc->last_waited == last_waited)) { 339 /* 340 * we want to go through our batch of 341 * requests and stop. So, we copy out 342 * the ioc->last_waited time and test 343 * against it before looping 344 */ 345 last_waited = ioc->last_waited; 346 if (need_resched()) 347 cond_resched(); 348 continue; 349 } 350 spin_lock(&device->io_lock); 351 requeue_list(pending_bios, pending, tail); 352 device->running_pending = 1; 353 354 spin_unlock(&device->io_lock); 355 btrfs_requeue_work(&device->work); 356 goto done; 357 } 358 /* unplug every 64 requests just for good measure */ 359 if (batch_run % 64 == 0) { 360 blk_finish_plug(&plug); 361 blk_start_plug(&plug); 362 sync_pending = 0; 363 } 364 } 365 366 cond_resched(); 367 if (again) 368 goto loop; 369 370 spin_lock(&device->io_lock); 371 if (device->pending_bios.head || device->pending_sync_bios.head) 372 goto loop_lock; 373 spin_unlock(&device->io_lock); 374 375 done: 376 blk_finish_plug(&plug); 377 } 378 379 static void pending_bios_fn(struct btrfs_work *work) 380 { 381 struct btrfs_device *device; 382 383 device = container_of(work, struct btrfs_device, work); 384 run_scheduled_bios(device); 385 } 386 387 static noinline int device_list_add(const char *path, 388 struct btrfs_super_block *disk_super, 389 u64 devid, struct btrfs_fs_devices **fs_devices_ret) 390 { 391 struct btrfs_device *device; 392 struct btrfs_fs_devices *fs_devices; 393 struct rcu_string *name; 394 u64 found_transid = btrfs_super_generation(disk_super); 395 396 fs_devices = find_fsid(disk_super->fsid); 397 if (!fs_devices) { 398 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 399 if (!fs_devices) 400 return -ENOMEM; 401 INIT_LIST_HEAD(&fs_devices->devices); 402 INIT_LIST_HEAD(&fs_devices->alloc_list); 403 list_add(&fs_devices->list, &fs_uuids); 404 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE); 405 fs_devices->latest_devid = devid; 406 fs_devices->latest_trans = found_transid; 407 mutex_init(&fs_devices->device_list_mutex); 408 device = NULL; 409 } else { 410 device = __find_device(&fs_devices->devices, devid, 411 disk_super->dev_item.uuid); 412 } 413 if (!device) { 414 if (fs_devices->opened) 415 return -EBUSY; 416 417 device = kzalloc(sizeof(*device), GFP_NOFS); 418 if (!device) { 419 /* we can safely leave the fs_devices entry around */ 420 return -ENOMEM; 421 } 422 device->devid = devid; 423 device->dev_stats_valid = 0; 424 device->work.func = pending_bios_fn; 425 memcpy(device->uuid, disk_super->dev_item.uuid, 426 BTRFS_UUID_SIZE); 427 spin_lock_init(&device->io_lock); 428 429 name = rcu_string_strdup(path, GFP_NOFS); 430 if (!name) { 431 kfree(device); 432 return -ENOMEM; 433 } 434 rcu_assign_pointer(device->name, name); 435 INIT_LIST_HEAD(&device->dev_alloc_list); 436 437 /* init readahead state */ 438 spin_lock_init(&device->reada_lock); 439 device->reada_curr_zone = NULL; 440 atomic_set(&device->reada_in_flight, 0); 441 device->reada_next = 0; 442 INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT); 443 INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT); 444 445 mutex_lock(&fs_devices->device_list_mutex); 446 list_add_rcu(&device->dev_list, &fs_devices->devices); 447 mutex_unlock(&fs_devices->device_list_mutex); 448 449 device->fs_devices = fs_devices; 450 fs_devices->num_devices++; 451 } else if (!device->name || strcmp(device->name->str, path)) { 452 name = rcu_string_strdup(path, GFP_NOFS); 453 if (!name) 454 return -ENOMEM; 455 rcu_string_free(device->name); 456 rcu_assign_pointer(device->name, name); 457 if (device->missing) { 458 fs_devices->missing_devices--; 459 device->missing = 0; 460 } 461 } 462 463 if (found_transid > fs_devices->latest_trans) { 464 fs_devices->latest_devid = devid; 465 fs_devices->latest_trans = found_transid; 466 } 467 *fs_devices_ret = fs_devices; 468 return 0; 469 } 470 471 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) 472 { 473 struct btrfs_fs_devices *fs_devices; 474 struct btrfs_device *device; 475 struct btrfs_device *orig_dev; 476 477 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 478 if (!fs_devices) 479 return ERR_PTR(-ENOMEM); 480 481 INIT_LIST_HEAD(&fs_devices->devices); 482 INIT_LIST_HEAD(&fs_devices->alloc_list); 483 INIT_LIST_HEAD(&fs_devices->list); 484 mutex_init(&fs_devices->device_list_mutex); 485 fs_devices->latest_devid = orig->latest_devid; 486 fs_devices->latest_trans = orig->latest_trans; 487 fs_devices->total_devices = orig->total_devices; 488 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid)); 489 490 /* We have held the volume lock, it is safe to get the devices. */ 491 list_for_each_entry(orig_dev, &orig->devices, dev_list) { 492 struct rcu_string *name; 493 494 device = kzalloc(sizeof(*device), GFP_NOFS); 495 if (!device) 496 goto error; 497 498 /* 499 * This is ok to do without rcu read locked because we hold the 500 * uuid mutex so nothing we touch in here is going to disappear. 501 */ 502 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS); 503 if (!name) { 504 kfree(device); 505 goto error; 506 } 507 rcu_assign_pointer(device->name, name); 508 509 device->devid = orig_dev->devid; 510 device->work.func = pending_bios_fn; 511 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid)); 512 spin_lock_init(&device->io_lock); 513 INIT_LIST_HEAD(&device->dev_list); 514 INIT_LIST_HEAD(&device->dev_alloc_list); 515 516 list_add(&device->dev_list, &fs_devices->devices); 517 device->fs_devices = fs_devices; 518 fs_devices->num_devices++; 519 } 520 return fs_devices; 521 error: 522 free_fs_devices(fs_devices); 523 return ERR_PTR(-ENOMEM); 524 } 525 526 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info, 527 struct btrfs_fs_devices *fs_devices, int step) 528 { 529 struct btrfs_device *device, *next; 530 531 struct block_device *latest_bdev = NULL; 532 u64 latest_devid = 0; 533 u64 latest_transid = 0; 534 535 mutex_lock(&uuid_mutex); 536 again: 537 /* This is the initialized path, it is safe to release the devices. */ 538 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { 539 if (device->in_fs_metadata) { 540 if (!device->is_tgtdev_for_dev_replace && 541 (!latest_transid || 542 device->generation > latest_transid)) { 543 latest_devid = device->devid; 544 latest_transid = device->generation; 545 latest_bdev = device->bdev; 546 } 547 continue; 548 } 549 550 if (device->devid == BTRFS_DEV_REPLACE_DEVID) { 551 /* 552 * In the first step, keep the device which has 553 * the correct fsid and the devid that is used 554 * for the dev_replace procedure. 555 * In the second step, the dev_replace state is 556 * read from the device tree and it is known 557 * whether the procedure is really active or 558 * not, which means whether this device is 559 * used or whether it should be removed. 560 */ 561 if (step == 0 || device->is_tgtdev_for_dev_replace) { 562 continue; 563 } 564 } 565 if (device->bdev) { 566 blkdev_put(device->bdev, device->mode); 567 device->bdev = NULL; 568 fs_devices->open_devices--; 569 } 570 if (device->writeable) { 571 list_del_init(&device->dev_alloc_list); 572 device->writeable = 0; 573 if (!device->is_tgtdev_for_dev_replace) 574 fs_devices->rw_devices--; 575 } 576 list_del_init(&device->dev_list); 577 fs_devices->num_devices--; 578 rcu_string_free(device->name); 579 kfree(device); 580 } 581 582 if (fs_devices->seed) { 583 fs_devices = fs_devices->seed; 584 goto again; 585 } 586 587 fs_devices->latest_bdev = latest_bdev; 588 fs_devices->latest_devid = latest_devid; 589 fs_devices->latest_trans = latest_transid; 590 591 mutex_unlock(&uuid_mutex); 592 } 593 594 static void __free_device(struct work_struct *work) 595 { 596 struct btrfs_device *device; 597 598 device = container_of(work, struct btrfs_device, rcu_work); 599 600 if (device->bdev) 601 blkdev_put(device->bdev, device->mode); 602 603 rcu_string_free(device->name); 604 kfree(device); 605 } 606 607 static void free_device(struct rcu_head *head) 608 { 609 struct btrfs_device *device; 610 611 device = container_of(head, struct btrfs_device, rcu); 612 613 INIT_WORK(&device->rcu_work, __free_device); 614 schedule_work(&device->rcu_work); 615 } 616 617 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 618 { 619 struct btrfs_device *device; 620 621 if (--fs_devices->opened > 0) 622 return 0; 623 624 mutex_lock(&fs_devices->device_list_mutex); 625 list_for_each_entry(device, &fs_devices->devices, dev_list) { 626 struct btrfs_device *new_device; 627 struct rcu_string *name; 628 629 if (device->bdev) 630 fs_devices->open_devices--; 631 632 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 633 list_del_init(&device->dev_alloc_list); 634 fs_devices->rw_devices--; 635 } 636 637 if (device->can_discard) 638 fs_devices->num_can_discard--; 639 640 new_device = kmalloc(sizeof(*new_device), GFP_NOFS); 641 BUG_ON(!new_device); /* -ENOMEM */ 642 memcpy(new_device, device, sizeof(*new_device)); 643 644 /* Safe because we are under uuid_mutex */ 645 if (device->name) { 646 name = rcu_string_strdup(device->name->str, GFP_NOFS); 647 BUG_ON(device->name && !name); /* -ENOMEM */ 648 rcu_assign_pointer(new_device->name, name); 649 } 650 new_device->bdev = NULL; 651 new_device->writeable = 0; 652 new_device->in_fs_metadata = 0; 653 new_device->can_discard = 0; 654 spin_lock_init(&new_device->io_lock); 655 list_replace_rcu(&device->dev_list, &new_device->dev_list); 656 657 call_rcu(&device->rcu, free_device); 658 } 659 mutex_unlock(&fs_devices->device_list_mutex); 660 661 WARN_ON(fs_devices->open_devices); 662 WARN_ON(fs_devices->rw_devices); 663 fs_devices->opened = 0; 664 fs_devices->seeding = 0; 665 666 return 0; 667 } 668 669 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) 670 { 671 struct btrfs_fs_devices *seed_devices = NULL; 672 int ret; 673 674 mutex_lock(&uuid_mutex); 675 ret = __btrfs_close_devices(fs_devices); 676 if (!fs_devices->opened) { 677 seed_devices = fs_devices->seed; 678 fs_devices->seed = NULL; 679 } 680 mutex_unlock(&uuid_mutex); 681 682 while (seed_devices) { 683 fs_devices = seed_devices; 684 seed_devices = fs_devices->seed; 685 __btrfs_close_devices(fs_devices); 686 free_fs_devices(fs_devices); 687 } 688 /* 689 * Wait for rcu kworkers under __btrfs_close_devices 690 * to finish all blkdev_puts so device is really 691 * free when umount is done. 692 */ 693 rcu_barrier(); 694 return ret; 695 } 696 697 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 698 fmode_t flags, void *holder) 699 { 700 struct request_queue *q; 701 struct block_device *bdev; 702 struct list_head *head = &fs_devices->devices; 703 struct btrfs_device *device; 704 struct block_device *latest_bdev = NULL; 705 struct buffer_head *bh; 706 struct btrfs_super_block *disk_super; 707 u64 latest_devid = 0; 708 u64 latest_transid = 0; 709 u64 devid; 710 int seeding = 1; 711 int ret = 0; 712 713 flags |= FMODE_EXCL; 714 715 list_for_each_entry(device, head, dev_list) { 716 if (device->bdev) 717 continue; 718 if (!device->name) 719 continue; 720 721 /* Just open everything we can; ignore failures here */ 722 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, 723 &bdev, &bh)) 724 continue; 725 726 disk_super = (struct btrfs_super_block *)bh->b_data; 727 devid = btrfs_stack_device_id(&disk_super->dev_item); 728 if (devid != device->devid) 729 goto error_brelse; 730 731 if (memcmp(device->uuid, disk_super->dev_item.uuid, 732 BTRFS_UUID_SIZE)) 733 goto error_brelse; 734 735 device->generation = btrfs_super_generation(disk_super); 736 if (!latest_transid || device->generation > latest_transid) { 737 latest_devid = devid; 738 latest_transid = device->generation; 739 latest_bdev = bdev; 740 } 741 742 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { 743 device->writeable = 0; 744 } else { 745 device->writeable = !bdev_read_only(bdev); 746 seeding = 0; 747 } 748 749 q = bdev_get_queue(bdev); 750 if (blk_queue_discard(q)) { 751 device->can_discard = 1; 752 fs_devices->num_can_discard++; 753 } 754 755 device->bdev = bdev; 756 device->in_fs_metadata = 0; 757 device->mode = flags; 758 759 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 760 fs_devices->rotating = 1; 761 762 fs_devices->open_devices++; 763 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 764 fs_devices->rw_devices++; 765 list_add(&device->dev_alloc_list, 766 &fs_devices->alloc_list); 767 } 768 brelse(bh); 769 continue; 770 771 error_brelse: 772 brelse(bh); 773 blkdev_put(bdev, flags); 774 continue; 775 } 776 if (fs_devices->open_devices == 0) { 777 ret = -EINVAL; 778 goto out; 779 } 780 fs_devices->seeding = seeding; 781 fs_devices->opened = 1; 782 fs_devices->latest_bdev = latest_bdev; 783 fs_devices->latest_devid = latest_devid; 784 fs_devices->latest_trans = latest_transid; 785 fs_devices->total_rw_bytes = 0; 786 out: 787 return ret; 788 } 789 790 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 791 fmode_t flags, void *holder) 792 { 793 int ret; 794 795 mutex_lock(&uuid_mutex); 796 if (fs_devices->opened) { 797 fs_devices->opened++; 798 ret = 0; 799 } else { 800 ret = __btrfs_open_devices(fs_devices, flags, holder); 801 } 802 mutex_unlock(&uuid_mutex); 803 return ret; 804 } 805 806 /* 807 * Look for a btrfs signature on a device. This may be called out of the mount path 808 * and we are not allowed to call set_blocksize during the scan. The superblock 809 * is read via pagecache 810 */ 811 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, 812 struct btrfs_fs_devices **fs_devices_ret) 813 { 814 struct btrfs_super_block *disk_super; 815 struct block_device *bdev; 816 struct page *page; 817 void *p; 818 int ret = -EINVAL; 819 u64 devid; 820 u64 transid; 821 u64 total_devices; 822 u64 bytenr; 823 pgoff_t index; 824 825 /* 826 * we would like to check all the supers, but that would make 827 * a btrfs mount succeed after a mkfs from a different FS. 828 * So, we need to add a special mount option to scan for 829 * later supers, using BTRFS_SUPER_MIRROR_MAX instead 830 */ 831 bytenr = btrfs_sb_offset(0); 832 flags |= FMODE_EXCL; 833 mutex_lock(&uuid_mutex); 834 835 bdev = blkdev_get_by_path(path, flags, holder); 836 837 if (IS_ERR(bdev)) { 838 ret = PTR_ERR(bdev); 839 goto error; 840 } 841 842 /* make sure our super fits in the device */ 843 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode)) 844 goto error_bdev_put; 845 846 /* make sure our super fits in the page */ 847 if (sizeof(*disk_super) > PAGE_CACHE_SIZE) 848 goto error_bdev_put; 849 850 /* make sure our super doesn't straddle pages on disk */ 851 index = bytenr >> PAGE_CACHE_SHIFT; 852 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index) 853 goto error_bdev_put; 854 855 /* pull in the page with our super */ 856 page = read_cache_page_gfp(bdev->bd_inode->i_mapping, 857 index, GFP_NOFS); 858 859 if (IS_ERR_OR_NULL(page)) 860 goto error_bdev_put; 861 862 p = kmap(page); 863 864 /* align our pointer to the offset of the super block */ 865 disk_super = p + (bytenr & ~PAGE_CACHE_MASK); 866 867 if (btrfs_super_bytenr(disk_super) != bytenr || 868 disk_super->magic != cpu_to_le64(BTRFS_MAGIC)) 869 goto error_unmap; 870 871 devid = btrfs_stack_device_id(&disk_super->dev_item); 872 transid = btrfs_super_generation(disk_super); 873 total_devices = btrfs_super_num_devices(disk_super); 874 875 if (disk_super->label[0]) { 876 if (disk_super->label[BTRFS_LABEL_SIZE - 1]) 877 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0'; 878 printk(KERN_INFO "device label %s ", disk_super->label); 879 } else { 880 printk(KERN_INFO "device fsid %pU ", disk_super->fsid); 881 } 882 883 printk(KERN_CONT "devid %llu transid %llu %s\n", 884 (unsigned long long)devid, (unsigned long long)transid, path); 885 886 ret = device_list_add(path, disk_super, devid, fs_devices_ret); 887 if (!ret && fs_devices_ret) 888 (*fs_devices_ret)->total_devices = total_devices; 889 890 error_unmap: 891 kunmap(page); 892 page_cache_release(page); 893 894 error_bdev_put: 895 blkdev_put(bdev, flags); 896 error: 897 mutex_unlock(&uuid_mutex); 898 return ret; 899 } 900 901 /* helper to account the used device space in the range */ 902 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, 903 u64 end, u64 *length) 904 { 905 struct btrfs_key key; 906 struct btrfs_root *root = device->dev_root; 907 struct btrfs_dev_extent *dev_extent; 908 struct btrfs_path *path; 909 u64 extent_end; 910 int ret; 911 int slot; 912 struct extent_buffer *l; 913 914 *length = 0; 915 916 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace) 917 return 0; 918 919 path = btrfs_alloc_path(); 920 if (!path) 921 return -ENOMEM; 922 path->reada = 2; 923 924 key.objectid = device->devid; 925 key.offset = start; 926 key.type = BTRFS_DEV_EXTENT_KEY; 927 928 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 929 if (ret < 0) 930 goto out; 931 if (ret > 0) { 932 ret = btrfs_previous_item(root, path, key.objectid, key.type); 933 if (ret < 0) 934 goto out; 935 } 936 937 while (1) { 938 l = path->nodes[0]; 939 slot = path->slots[0]; 940 if (slot >= btrfs_header_nritems(l)) { 941 ret = btrfs_next_leaf(root, path); 942 if (ret == 0) 943 continue; 944 if (ret < 0) 945 goto out; 946 947 break; 948 } 949 btrfs_item_key_to_cpu(l, &key, slot); 950 951 if (key.objectid < device->devid) 952 goto next; 953 954 if (key.objectid > device->devid) 955 break; 956 957 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 958 goto next; 959 960 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 961 extent_end = key.offset + btrfs_dev_extent_length(l, 962 dev_extent); 963 if (key.offset <= start && extent_end > end) { 964 *length = end - start + 1; 965 break; 966 } else if (key.offset <= start && extent_end > start) 967 *length += extent_end - start; 968 else if (key.offset > start && extent_end <= end) 969 *length += extent_end - key.offset; 970 else if (key.offset > start && key.offset <= end) { 971 *length += end - key.offset + 1; 972 break; 973 } else if (key.offset > end) 974 break; 975 976 next: 977 path->slots[0]++; 978 } 979 ret = 0; 980 out: 981 btrfs_free_path(path); 982 return ret; 983 } 984 985 /* 986 * find_free_dev_extent - find free space in the specified device 987 * @device: the device which we search the free space in 988 * @num_bytes: the size of the free space that we need 989 * @start: store the start of the free space. 990 * @len: the size of the free space. that we find, or the size of the max 991 * free space if we don't find suitable free space 992 * 993 * this uses a pretty simple search, the expectation is that it is 994 * called very infrequently and that a given device has a small number 995 * of extents 996 * 997 * @start is used to store the start of the free space if we find. But if we 998 * don't find suitable free space, it will be used to store the start position 999 * of the max free space. 1000 * 1001 * @len is used to store the size of the free space that we find. 1002 * But if we don't find suitable free space, it is used to store the size of 1003 * the max free space. 1004 */ 1005 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes, 1006 u64 *start, u64 *len) 1007 { 1008 struct btrfs_key key; 1009 struct btrfs_root *root = device->dev_root; 1010 struct btrfs_dev_extent *dev_extent; 1011 struct btrfs_path *path; 1012 u64 hole_size; 1013 u64 max_hole_start; 1014 u64 max_hole_size; 1015 u64 extent_end; 1016 u64 search_start; 1017 u64 search_end = device->total_bytes; 1018 int ret; 1019 int slot; 1020 struct extent_buffer *l; 1021 1022 /* FIXME use last free of some kind */ 1023 1024 /* we don't want to overwrite the superblock on the drive, 1025 * so we make sure to start at an offset of at least 1MB 1026 */ 1027 search_start = max(root->fs_info->alloc_start, 1024ull * 1024); 1028 1029 max_hole_start = search_start; 1030 max_hole_size = 0; 1031 hole_size = 0; 1032 1033 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) { 1034 ret = -ENOSPC; 1035 goto error; 1036 } 1037 1038 path = btrfs_alloc_path(); 1039 if (!path) { 1040 ret = -ENOMEM; 1041 goto error; 1042 } 1043 path->reada = 2; 1044 1045 key.objectid = device->devid; 1046 key.offset = search_start; 1047 key.type = BTRFS_DEV_EXTENT_KEY; 1048 1049 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1050 if (ret < 0) 1051 goto out; 1052 if (ret > 0) { 1053 ret = btrfs_previous_item(root, path, key.objectid, key.type); 1054 if (ret < 0) 1055 goto out; 1056 } 1057 1058 while (1) { 1059 l = path->nodes[0]; 1060 slot = path->slots[0]; 1061 if (slot >= btrfs_header_nritems(l)) { 1062 ret = btrfs_next_leaf(root, path); 1063 if (ret == 0) 1064 continue; 1065 if (ret < 0) 1066 goto out; 1067 1068 break; 1069 } 1070 btrfs_item_key_to_cpu(l, &key, slot); 1071 1072 if (key.objectid < device->devid) 1073 goto next; 1074 1075 if (key.objectid > device->devid) 1076 break; 1077 1078 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY) 1079 goto next; 1080 1081 if (key.offset > search_start) { 1082 hole_size = key.offset - search_start; 1083 1084 if (hole_size > max_hole_size) { 1085 max_hole_start = search_start; 1086 max_hole_size = hole_size; 1087 } 1088 1089 /* 1090 * If this free space is greater than which we need, 1091 * it must be the max free space that we have found 1092 * until now, so max_hole_start must point to the start 1093 * of this free space and the length of this free space 1094 * is stored in max_hole_size. Thus, we return 1095 * max_hole_start and max_hole_size and go back to the 1096 * caller. 1097 */ 1098 if (hole_size >= num_bytes) { 1099 ret = 0; 1100 goto out; 1101 } 1102 } 1103 1104 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 1105 extent_end = key.offset + btrfs_dev_extent_length(l, 1106 dev_extent); 1107 if (extent_end > search_start) 1108 search_start = extent_end; 1109 next: 1110 path->slots[0]++; 1111 cond_resched(); 1112 } 1113 1114 /* 1115 * At this point, search_start should be the end of 1116 * allocated dev extents, and when shrinking the device, 1117 * search_end may be smaller than search_start. 1118 */ 1119 if (search_end > search_start) 1120 hole_size = search_end - search_start; 1121 1122 if (hole_size > max_hole_size) { 1123 max_hole_start = search_start; 1124 max_hole_size = hole_size; 1125 } 1126 1127 /* See above. */ 1128 if (hole_size < num_bytes) 1129 ret = -ENOSPC; 1130 else 1131 ret = 0; 1132 1133 out: 1134 btrfs_free_path(path); 1135 error: 1136 *start = max_hole_start; 1137 if (len) 1138 *len = max_hole_size; 1139 return ret; 1140 } 1141 1142 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, 1143 struct btrfs_device *device, 1144 u64 start) 1145 { 1146 int ret; 1147 struct btrfs_path *path; 1148 struct btrfs_root *root = device->dev_root; 1149 struct btrfs_key key; 1150 struct btrfs_key found_key; 1151 struct extent_buffer *leaf = NULL; 1152 struct btrfs_dev_extent *extent = NULL; 1153 1154 path = btrfs_alloc_path(); 1155 if (!path) 1156 return -ENOMEM; 1157 1158 key.objectid = device->devid; 1159 key.offset = start; 1160 key.type = BTRFS_DEV_EXTENT_KEY; 1161 again: 1162 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1163 if (ret > 0) { 1164 ret = btrfs_previous_item(root, path, key.objectid, 1165 BTRFS_DEV_EXTENT_KEY); 1166 if (ret) 1167 goto out; 1168 leaf = path->nodes[0]; 1169 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 1170 extent = btrfs_item_ptr(leaf, path->slots[0], 1171 struct btrfs_dev_extent); 1172 BUG_ON(found_key.offset > start || found_key.offset + 1173 btrfs_dev_extent_length(leaf, extent) < start); 1174 key = found_key; 1175 btrfs_release_path(path); 1176 goto again; 1177 } else if (ret == 0) { 1178 leaf = path->nodes[0]; 1179 extent = btrfs_item_ptr(leaf, path->slots[0], 1180 struct btrfs_dev_extent); 1181 } else { 1182 btrfs_error(root->fs_info, ret, "Slot search failed"); 1183 goto out; 1184 } 1185 1186 if (device->bytes_used > 0) { 1187 u64 len = btrfs_dev_extent_length(leaf, extent); 1188 device->bytes_used -= len; 1189 spin_lock(&root->fs_info->free_chunk_lock); 1190 root->fs_info->free_chunk_space += len; 1191 spin_unlock(&root->fs_info->free_chunk_lock); 1192 } 1193 ret = btrfs_del_item(trans, root, path); 1194 if (ret) { 1195 btrfs_error(root->fs_info, ret, 1196 "Failed to remove dev extent item"); 1197 } 1198 out: 1199 btrfs_free_path(path); 1200 return ret; 1201 } 1202 1203 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, 1204 struct btrfs_device *device, 1205 u64 chunk_tree, u64 chunk_objectid, 1206 u64 chunk_offset, u64 start, u64 num_bytes) 1207 { 1208 int ret; 1209 struct btrfs_path *path; 1210 struct btrfs_root *root = device->dev_root; 1211 struct btrfs_dev_extent *extent; 1212 struct extent_buffer *leaf; 1213 struct btrfs_key key; 1214 1215 WARN_ON(!device->in_fs_metadata); 1216 WARN_ON(device->is_tgtdev_for_dev_replace); 1217 path = btrfs_alloc_path(); 1218 if (!path) 1219 return -ENOMEM; 1220 1221 key.objectid = device->devid; 1222 key.offset = start; 1223 key.type = BTRFS_DEV_EXTENT_KEY; 1224 ret = btrfs_insert_empty_item(trans, root, path, &key, 1225 sizeof(*extent)); 1226 if (ret) 1227 goto out; 1228 1229 leaf = path->nodes[0]; 1230 extent = btrfs_item_ptr(leaf, path->slots[0], 1231 struct btrfs_dev_extent); 1232 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree); 1233 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid); 1234 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset); 1235 1236 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid, 1237 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent), 1238 BTRFS_UUID_SIZE); 1239 1240 btrfs_set_dev_extent_length(leaf, extent, num_bytes); 1241 btrfs_mark_buffer_dirty(leaf); 1242 out: 1243 btrfs_free_path(path); 1244 return ret; 1245 } 1246 1247 static noinline int find_next_chunk(struct btrfs_root *root, 1248 u64 objectid, u64 *offset) 1249 { 1250 struct btrfs_path *path; 1251 int ret; 1252 struct btrfs_key key; 1253 struct btrfs_chunk *chunk; 1254 struct btrfs_key found_key; 1255 1256 path = btrfs_alloc_path(); 1257 if (!path) 1258 return -ENOMEM; 1259 1260 key.objectid = objectid; 1261 key.offset = (u64)-1; 1262 key.type = BTRFS_CHUNK_ITEM_KEY; 1263 1264 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1265 if (ret < 0) 1266 goto error; 1267 1268 BUG_ON(ret == 0); /* Corruption */ 1269 1270 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY); 1271 if (ret) { 1272 *offset = 0; 1273 } else { 1274 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1275 path->slots[0]); 1276 if (found_key.objectid != objectid) 1277 *offset = 0; 1278 else { 1279 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], 1280 struct btrfs_chunk); 1281 *offset = found_key.offset + 1282 btrfs_chunk_length(path->nodes[0], chunk); 1283 } 1284 } 1285 ret = 0; 1286 error: 1287 btrfs_free_path(path); 1288 return ret; 1289 } 1290 1291 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid) 1292 { 1293 int ret; 1294 struct btrfs_key key; 1295 struct btrfs_key found_key; 1296 struct btrfs_path *path; 1297 1298 root = root->fs_info->chunk_root; 1299 1300 path = btrfs_alloc_path(); 1301 if (!path) 1302 return -ENOMEM; 1303 1304 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1305 key.type = BTRFS_DEV_ITEM_KEY; 1306 key.offset = (u64)-1; 1307 1308 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 1309 if (ret < 0) 1310 goto error; 1311 1312 BUG_ON(ret == 0); /* Corruption */ 1313 1314 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID, 1315 BTRFS_DEV_ITEM_KEY); 1316 if (ret) { 1317 *objectid = 1; 1318 } else { 1319 btrfs_item_key_to_cpu(path->nodes[0], &found_key, 1320 path->slots[0]); 1321 *objectid = found_key.offset + 1; 1322 } 1323 ret = 0; 1324 error: 1325 btrfs_free_path(path); 1326 return ret; 1327 } 1328 1329 /* 1330 * the device information is stored in the chunk root 1331 * the btrfs_device struct should be fully filled in 1332 */ 1333 static int btrfs_add_device(struct btrfs_trans_handle *trans, 1334 struct btrfs_root *root, 1335 struct btrfs_device *device) 1336 { 1337 int ret; 1338 struct btrfs_path *path; 1339 struct btrfs_dev_item *dev_item; 1340 struct extent_buffer *leaf; 1341 struct btrfs_key key; 1342 unsigned long ptr; 1343 1344 root = root->fs_info->chunk_root; 1345 1346 path = btrfs_alloc_path(); 1347 if (!path) 1348 return -ENOMEM; 1349 1350 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1351 key.type = BTRFS_DEV_ITEM_KEY; 1352 key.offset = device->devid; 1353 1354 ret = btrfs_insert_empty_item(trans, root, path, &key, 1355 sizeof(*dev_item)); 1356 if (ret) 1357 goto out; 1358 1359 leaf = path->nodes[0]; 1360 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 1361 1362 btrfs_set_device_id(leaf, dev_item, device->devid); 1363 btrfs_set_device_generation(leaf, dev_item, 0); 1364 btrfs_set_device_type(leaf, dev_item, device->type); 1365 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 1366 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 1367 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 1368 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes); 1369 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 1370 btrfs_set_device_group(leaf, dev_item, 0); 1371 btrfs_set_device_seek_speed(leaf, dev_item, 0); 1372 btrfs_set_device_bandwidth(leaf, dev_item, 0); 1373 btrfs_set_device_start_offset(leaf, dev_item, 0); 1374 1375 ptr = (unsigned long)btrfs_device_uuid(dev_item); 1376 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 1377 ptr = (unsigned long)btrfs_device_fsid(dev_item); 1378 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE); 1379 btrfs_mark_buffer_dirty(leaf); 1380 1381 ret = 0; 1382 out: 1383 btrfs_free_path(path); 1384 return ret; 1385 } 1386 1387 static int btrfs_rm_dev_item(struct btrfs_root *root, 1388 struct btrfs_device *device) 1389 { 1390 int ret; 1391 struct btrfs_path *path; 1392 struct btrfs_key key; 1393 struct btrfs_trans_handle *trans; 1394 1395 root = root->fs_info->chunk_root; 1396 1397 path = btrfs_alloc_path(); 1398 if (!path) 1399 return -ENOMEM; 1400 1401 trans = btrfs_start_transaction(root, 0); 1402 if (IS_ERR(trans)) { 1403 btrfs_free_path(path); 1404 return PTR_ERR(trans); 1405 } 1406 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1407 key.type = BTRFS_DEV_ITEM_KEY; 1408 key.offset = device->devid; 1409 lock_chunks(root); 1410 1411 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 1412 if (ret < 0) 1413 goto out; 1414 1415 if (ret > 0) { 1416 ret = -ENOENT; 1417 goto out; 1418 } 1419 1420 ret = btrfs_del_item(trans, root, path); 1421 if (ret) 1422 goto out; 1423 out: 1424 btrfs_free_path(path); 1425 unlock_chunks(root); 1426 btrfs_commit_transaction(trans, root); 1427 return ret; 1428 } 1429 1430 int btrfs_rm_device(struct btrfs_root *root, char *device_path) 1431 { 1432 struct btrfs_device *device; 1433 struct btrfs_device *next_device; 1434 struct block_device *bdev; 1435 struct buffer_head *bh = NULL; 1436 struct btrfs_super_block *disk_super; 1437 struct btrfs_fs_devices *cur_devices; 1438 u64 all_avail; 1439 u64 devid; 1440 u64 num_devices; 1441 u8 *dev_uuid; 1442 unsigned seq; 1443 int ret = 0; 1444 bool clear_super = false; 1445 1446 mutex_lock(&uuid_mutex); 1447 1448 do { 1449 seq = read_seqbegin(&root->fs_info->profiles_lock); 1450 1451 all_avail = root->fs_info->avail_data_alloc_bits | 1452 root->fs_info->avail_system_alloc_bits | 1453 root->fs_info->avail_metadata_alloc_bits; 1454 } while (read_seqretry(&root->fs_info->profiles_lock, seq)); 1455 1456 num_devices = root->fs_info->fs_devices->num_devices; 1457 btrfs_dev_replace_lock(&root->fs_info->dev_replace); 1458 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) { 1459 WARN_ON(num_devices < 1); 1460 num_devices--; 1461 } 1462 btrfs_dev_replace_unlock(&root->fs_info->dev_replace); 1463 1464 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) { 1465 printk(KERN_ERR "btrfs: unable to go below four devices " 1466 "on raid10\n"); 1467 ret = -EINVAL; 1468 goto out; 1469 } 1470 1471 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) { 1472 printk(KERN_ERR "btrfs: unable to go below two " 1473 "devices on raid1\n"); 1474 ret = -EINVAL; 1475 goto out; 1476 } 1477 1478 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) && 1479 root->fs_info->fs_devices->rw_devices <= 2) { 1480 printk(KERN_ERR "btrfs: unable to go below two " 1481 "devices on raid5\n"); 1482 ret = -EINVAL; 1483 goto out; 1484 } 1485 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) && 1486 root->fs_info->fs_devices->rw_devices <= 3) { 1487 printk(KERN_ERR "btrfs: unable to go below three " 1488 "devices on raid6\n"); 1489 ret = -EINVAL; 1490 goto out; 1491 } 1492 1493 if (strcmp(device_path, "missing") == 0) { 1494 struct list_head *devices; 1495 struct btrfs_device *tmp; 1496 1497 device = NULL; 1498 devices = &root->fs_info->fs_devices->devices; 1499 /* 1500 * It is safe to read the devices since the volume_mutex 1501 * is held. 1502 */ 1503 list_for_each_entry(tmp, devices, dev_list) { 1504 if (tmp->in_fs_metadata && 1505 !tmp->is_tgtdev_for_dev_replace && 1506 !tmp->bdev) { 1507 device = tmp; 1508 break; 1509 } 1510 } 1511 bdev = NULL; 1512 bh = NULL; 1513 disk_super = NULL; 1514 if (!device) { 1515 printk(KERN_ERR "btrfs: no missing devices found to " 1516 "remove\n"); 1517 goto out; 1518 } 1519 } else { 1520 ret = btrfs_get_bdev_and_sb(device_path, 1521 FMODE_WRITE | FMODE_EXCL, 1522 root->fs_info->bdev_holder, 0, 1523 &bdev, &bh); 1524 if (ret) 1525 goto out; 1526 disk_super = (struct btrfs_super_block *)bh->b_data; 1527 devid = btrfs_stack_device_id(&disk_super->dev_item); 1528 dev_uuid = disk_super->dev_item.uuid; 1529 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1530 disk_super->fsid); 1531 if (!device) { 1532 ret = -ENOENT; 1533 goto error_brelse; 1534 } 1535 } 1536 1537 if (device->is_tgtdev_for_dev_replace) { 1538 pr_err("btrfs: unable to remove the dev_replace target dev\n"); 1539 ret = -EINVAL; 1540 goto error_brelse; 1541 } 1542 1543 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) { 1544 printk(KERN_ERR "btrfs: unable to remove the only writeable " 1545 "device\n"); 1546 ret = -EINVAL; 1547 goto error_brelse; 1548 } 1549 1550 if (device->writeable) { 1551 lock_chunks(root); 1552 list_del_init(&device->dev_alloc_list); 1553 unlock_chunks(root); 1554 root->fs_info->fs_devices->rw_devices--; 1555 clear_super = true; 1556 } 1557 1558 ret = btrfs_shrink_device(device, 0); 1559 if (ret) 1560 goto error_undo; 1561 1562 /* 1563 * TODO: the superblock still includes this device in its num_devices 1564 * counter although write_all_supers() is not locked out. This 1565 * could give a filesystem state which requires a degraded mount. 1566 */ 1567 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device); 1568 if (ret) 1569 goto error_undo; 1570 1571 spin_lock(&root->fs_info->free_chunk_lock); 1572 root->fs_info->free_chunk_space = device->total_bytes - 1573 device->bytes_used; 1574 spin_unlock(&root->fs_info->free_chunk_lock); 1575 1576 device->in_fs_metadata = 0; 1577 btrfs_scrub_cancel_dev(root->fs_info, device); 1578 1579 /* 1580 * the device list mutex makes sure that we don't change 1581 * the device list while someone else is writing out all 1582 * the device supers. 1583 */ 1584 1585 cur_devices = device->fs_devices; 1586 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1587 list_del_rcu(&device->dev_list); 1588 1589 device->fs_devices->num_devices--; 1590 device->fs_devices->total_devices--; 1591 1592 if (device->missing) 1593 root->fs_info->fs_devices->missing_devices--; 1594 1595 next_device = list_entry(root->fs_info->fs_devices->devices.next, 1596 struct btrfs_device, dev_list); 1597 if (device->bdev == root->fs_info->sb->s_bdev) 1598 root->fs_info->sb->s_bdev = next_device->bdev; 1599 if (device->bdev == root->fs_info->fs_devices->latest_bdev) 1600 root->fs_info->fs_devices->latest_bdev = next_device->bdev; 1601 1602 if (device->bdev) 1603 device->fs_devices->open_devices--; 1604 1605 call_rcu(&device->rcu, free_device); 1606 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1607 1608 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1; 1609 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices); 1610 1611 if (cur_devices->open_devices == 0) { 1612 struct btrfs_fs_devices *fs_devices; 1613 fs_devices = root->fs_info->fs_devices; 1614 while (fs_devices) { 1615 if (fs_devices->seed == cur_devices) 1616 break; 1617 fs_devices = fs_devices->seed; 1618 } 1619 fs_devices->seed = cur_devices->seed; 1620 cur_devices->seed = NULL; 1621 lock_chunks(root); 1622 __btrfs_close_devices(cur_devices); 1623 unlock_chunks(root); 1624 free_fs_devices(cur_devices); 1625 } 1626 1627 root->fs_info->num_tolerated_disk_barrier_failures = 1628 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 1629 1630 /* 1631 * at this point, the device is zero sized. We want to 1632 * remove it from the devices list and zero out the old super 1633 */ 1634 if (clear_super && disk_super) { 1635 /* make sure this device isn't detected as part of 1636 * the FS anymore 1637 */ 1638 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 1639 set_buffer_dirty(bh); 1640 sync_dirty_buffer(bh); 1641 } 1642 1643 ret = 0; 1644 1645 /* Notify udev that device has changed */ 1646 if (bdev) 1647 btrfs_kobject_uevent(bdev, KOBJ_CHANGE); 1648 1649 error_brelse: 1650 brelse(bh); 1651 if (bdev) 1652 blkdev_put(bdev, FMODE_READ | FMODE_EXCL); 1653 out: 1654 mutex_unlock(&uuid_mutex); 1655 return ret; 1656 error_undo: 1657 if (device->writeable) { 1658 lock_chunks(root); 1659 list_add(&device->dev_alloc_list, 1660 &root->fs_info->fs_devices->alloc_list); 1661 unlock_chunks(root); 1662 root->fs_info->fs_devices->rw_devices++; 1663 } 1664 goto error_brelse; 1665 } 1666 1667 void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info, 1668 struct btrfs_device *srcdev) 1669 { 1670 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex)); 1671 list_del_rcu(&srcdev->dev_list); 1672 list_del_rcu(&srcdev->dev_alloc_list); 1673 fs_info->fs_devices->num_devices--; 1674 if (srcdev->missing) { 1675 fs_info->fs_devices->missing_devices--; 1676 fs_info->fs_devices->rw_devices++; 1677 } 1678 if (srcdev->can_discard) 1679 fs_info->fs_devices->num_can_discard--; 1680 if (srcdev->bdev) 1681 fs_info->fs_devices->open_devices--; 1682 1683 call_rcu(&srcdev->rcu, free_device); 1684 } 1685 1686 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 1687 struct btrfs_device *tgtdev) 1688 { 1689 struct btrfs_device *next_device; 1690 1691 WARN_ON(!tgtdev); 1692 mutex_lock(&fs_info->fs_devices->device_list_mutex); 1693 if (tgtdev->bdev) { 1694 btrfs_scratch_superblock(tgtdev); 1695 fs_info->fs_devices->open_devices--; 1696 } 1697 fs_info->fs_devices->num_devices--; 1698 if (tgtdev->can_discard) 1699 fs_info->fs_devices->num_can_discard++; 1700 1701 next_device = list_entry(fs_info->fs_devices->devices.next, 1702 struct btrfs_device, dev_list); 1703 if (tgtdev->bdev == fs_info->sb->s_bdev) 1704 fs_info->sb->s_bdev = next_device->bdev; 1705 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev) 1706 fs_info->fs_devices->latest_bdev = next_device->bdev; 1707 list_del_rcu(&tgtdev->dev_list); 1708 1709 call_rcu(&tgtdev->rcu, free_device); 1710 1711 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 1712 } 1713 1714 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path, 1715 struct btrfs_device **device) 1716 { 1717 int ret = 0; 1718 struct btrfs_super_block *disk_super; 1719 u64 devid; 1720 u8 *dev_uuid; 1721 struct block_device *bdev; 1722 struct buffer_head *bh; 1723 1724 *device = NULL; 1725 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ, 1726 root->fs_info->bdev_holder, 0, &bdev, &bh); 1727 if (ret) 1728 return ret; 1729 disk_super = (struct btrfs_super_block *)bh->b_data; 1730 devid = btrfs_stack_device_id(&disk_super->dev_item); 1731 dev_uuid = disk_super->dev_item.uuid; 1732 *device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1733 disk_super->fsid); 1734 brelse(bh); 1735 if (!*device) 1736 ret = -ENOENT; 1737 blkdev_put(bdev, FMODE_READ); 1738 return ret; 1739 } 1740 1741 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root, 1742 char *device_path, 1743 struct btrfs_device **device) 1744 { 1745 *device = NULL; 1746 if (strcmp(device_path, "missing") == 0) { 1747 struct list_head *devices; 1748 struct btrfs_device *tmp; 1749 1750 devices = &root->fs_info->fs_devices->devices; 1751 /* 1752 * It is safe to read the devices since the volume_mutex 1753 * is held by the caller. 1754 */ 1755 list_for_each_entry(tmp, devices, dev_list) { 1756 if (tmp->in_fs_metadata && !tmp->bdev) { 1757 *device = tmp; 1758 break; 1759 } 1760 } 1761 1762 if (!*device) { 1763 pr_err("btrfs: no missing device found\n"); 1764 return -ENOENT; 1765 } 1766 1767 return 0; 1768 } else { 1769 return btrfs_find_device_by_path(root, device_path, device); 1770 } 1771 } 1772 1773 /* 1774 * does all the dirty work required for changing file system's UUID. 1775 */ 1776 static int btrfs_prepare_sprout(struct btrfs_root *root) 1777 { 1778 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 1779 struct btrfs_fs_devices *old_devices; 1780 struct btrfs_fs_devices *seed_devices; 1781 struct btrfs_super_block *disk_super = root->fs_info->super_copy; 1782 struct btrfs_device *device; 1783 u64 super_flags; 1784 1785 BUG_ON(!mutex_is_locked(&uuid_mutex)); 1786 if (!fs_devices->seeding) 1787 return -EINVAL; 1788 1789 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS); 1790 if (!seed_devices) 1791 return -ENOMEM; 1792 1793 old_devices = clone_fs_devices(fs_devices); 1794 if (IS_ERR(old_devices)) { 1795 kfree(seed_devices); 1796 return PTR_ERR(old_devices); 1797 } 1798 1799 list_add(&old_devices->list, &fs_uuids); 1800 1801 memcpy(seed_devices, fs_devices, sizeof(*seed_devices)); 1802 seed_devices->opened = 1; 1803 INIT_LIST_HEAD(&seed_devices->devices); 1804 INIT_LIST_HEAD(&seed_devices->alloc_list); 1805 mutex_init(&seed_devices->device_list_mutex); 1806 1807 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1808 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices, 1809 synchronize_rcu); 1810 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1811 1812 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list); 1813 list_for_each_entry(device, &seed_devices->devices, dev_list) { 1814 device->fs_devices = seed_devices; 1815 } 1816 1817 fs_devices->seeding = 0; 1818 fs_devices->num_devices = 0; 1819 fs_devices->open_devices = 0; 1820 fs_devices->total_devices = 0; 1821 fs_devices->seed = seed_devices; 1822 1823 generate_random_uuid(fs_devices->fsid); 1824 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1825 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1826 super_flags = btrfs_super_flags(disk_super) & 1827 ~BTRFS_SUPER_FLAG_SEEDING; 1828 btrfs_set_super_flags(disk_super, super_flags); 1829 1830 return 0; 1831 } 1832 1833 /* 1834 * strore the expected generation for seed devices in device items. 1835 */ 1836 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans, 1837 struct btrfs_root *root) 1838 { 1839 struct btrfs_path *path; 1840 struct extent_buffer *leaf; 1841 struct btrfs_dev_item *dev_item; 1842 struct btrfs_device *device; 1843 struct btrfs_key key; 1844 u8 fs_uuid[BTRFS_UUID_SIZE]; 1845 u8 dev_uuid[BTRFS_UUID_SIZE]; 1846 u64 devid; 1847 int ret; 1848 1849 path = btrfs_alloc_path(); 1850 if (!path) 1851 return -ENOMEM; 1852 1853 root = root->fs_info->chunk_root; 1854 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 1855 key.offset = 0; 1856 key.type = BTRFS_DEV_ITEM_KEY; 1857 1858 while (1) { 1859 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 1860 if (ret < 0) 1861 goto error; 1862 1863 leaf = path->nodes[0]; 1864 next_slot: 1865 if (path->slots[0] >= btrfs_header_nritems(leaf)) { 1866 ret = btrfs_next_leaf(root, path); 1867 if (ret > 0) 1868 break; 1869 if (ret < 0) 1870 goto error; 1871 leaf = path->nodes[0]; 1872 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1873 btrfs_release_path(path); 1874 continue; 1875 } 1876 1877 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); 1878 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID || 1879 key.type != BTRFS_DEV_ITEM_KEY) 1880 break; 1881 1882 dev_item = btrfs_item_ptr(leaf, path->slots[0], 1883 struct btrfs_dev_item); 1884 devid = btrfs_device_id(leaf, dev_item); 1885 read_extent_buffer(leaf, dev_uuid, 1886 (unsigned long)btrfs_device_uuid(dev_item), 1887 BTRFS_UUID_SIZE); 1888 read_extent_buffer(leaf, fs_uuid, 1889 (unsigned long)btrfs_device_fsid(dev_item), 1890 BTRFS_UUID_SIZE); 1891 device = btrfs_find_device(root->fs_info, devid, dev_uuid, 1892 fs_uuid); 1893 BUG_ON(!device); /* Logic error */ 1894 1895 if (device->fs_devices->seeding) { 1896 btrfs_set_device_generation(leaf, dev_item, 1897 device->generation); 1898 btrfs_mark_buffer_dirty(leaf); 1899 } 1900 1901 path->slots[0]++; 1902 goto next_slot; 1903 } 1904 ret = 0; 1905 error: 1906 btrfs_free_path(path); 1907 return ret; 1908 } 1909 1910 int btrfs_init_new_device(struct btrfs_root *root, char *device_path) 1911 { 1912 struct request_queue *q; 1913 struct btrfs_trans_handle *trans; 1914 struct btrfs_device *device; 1915 struct block_device *bdev; 1916 struct list_head *devices; 1917 struct super_block *sb = root->fs_info->sb; 1918 struct rcu_string *name; 1919 u64 total_bytes; 1920 int seeding_dev = 0; 1921 int ret = 0; 1922 1923 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) 1924 return -EROFS; 1925 1926 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 1927 root->fs_info->bdev_holder); 1928 if (IS_ERR(bdev)) 1929 return PTR_ERR(bdev); 1930 1931 if (root->fs_info->fs_devices->seeding) { 1932 seeding_dev = 1; 1933 down_write(&sb->s_umount); 1934 mutex_lock(&uuid_mutex); 1935 } 1936 1937 filemap_write_and_wait(bdev->bd_inode->i_mapping); 1938 1939 devices = &root->fs_info->fs_devices->devices; 1940 1941 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 1942 list_for_each_entry(device, devices, dev_list) { 1943 if (device->bdev == bdev) { 1944 ret = -EEXIST; 1945 mutex_unlock( 1946 &root->fs_info->fs_devices->device_list_mutex); 1947 goto error; 1948 } 1949 } 1950 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 1951 1952 device = kzalloc(sizeof(*device), GFP_NOFS); 1953 if (!device) { 1954 /* we can safely leave the fs_devices entry around */ 1955 ret = -ENOMEM; 1956 goto error; 1957 } 1958 1959 name = rcu_string_strdup(device_path, GFP_NOFS); 1960 if (!name) { 1961 kfree(device); 1962 ret = -ENOMEM; 1963 goto error; 1964 } 1965 rcu_assign_pointer(device->name, name); 1966 1967 ret = find_next_devid(root, &device->devid); 1968 if (ret) { 1969 rcu_string_free(device->name); 1970 kfree(device); 1971 goto error; 1972 } 1973 1974 trans = btrfs_start_transaction(root, 0); 1975 if (IS_ERR(trans)) { 1976 rcu_string_free(device->name); 1977 kfree(device); 1978 ret = PTR_ERR(trans); 1979 goto error; 1980 } 1981 1982 lock_chunks(root); 1983 1984 q = bdev_get_queue(bdev); 1985 if (blk_queue_discard(q)) 1986 device->can_discard = 1; 1987 device->writeable = 1; 1988 device->work.func = pending_bios_fn; 1989 generate_random_uuid(device->uuid); 1990 spin_lock_init(&device->io_lock); 1991 device->generation = trans->transid; 1992 device->io_width = root->sectorsize; 1993 device->io_align = root->sectorsize; 1994 device->sector_size = root->sectorsize; 1995 device->total_bytes = i_size_read(bdev->bd_inode); 1996 device->disk_total_bytes = device->total_bytes; 1997 device->dev_root = root->fs_info->dev_root; 1998 device->bdev = bdev; 1999 device->in_fs_metadata = 1; 2000 device->is_tgtdev_for_dev_replace = 0; 2001 device->mode = FMODE_EXCL; 2002 set_blocksize(device->bdev, 4096); 2003 2004 if (seeding_dev) { 2005 sb->s_flags &= ~MS_RDONLY; 2006 ret = btrfs_prepare_sprout(root); 2007 BUG_ON(ret); /* -ENOMEM */ 2008 } 2009 2010 device->fs_devices = root->fs_info->fs_devices; 2011 2012 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2013 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices); 2014 list_add(&device->dev_alloc_list, 2015 &root->fs_info->fs_devices->alloc_list); 2016 root->fs_info->fs_devices->num_devices++; 2017 root->fs_info->fs_devices->open_devices++; 2018 root->fs_info->fs_devices->rw_devices++; 2019 root->fs_info->fs_devices->total_devices++; 2020 if (device->can_discard) 2021 root->fs_info->fs_devices->num_can_discard++; 2022 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes; 2023 2024 spin_lock(&root->fs_info->free_chunk_lock); 2025 root->fs_info->free_chunk_space += device->total_bytes; 2026 spin_unlock(&root->fs_info->free_chunk_lock); 2027 2028 if (!blk_queue_nonrot(bdev_get_queue(bdev))) 2029 root->fs_info->fs_devices->rotating = 1; 2030 2031 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy); 2032 btrfs_set_super_total_bytes(root->fs_info->super_copy, 2033 total_bytes + device->total_bytes); 2034 2035 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy); 2036 btrfs_set_super_num_devices(root->fs_info->super_copy, 2037 total_bytes + 1); 2038 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2039 2040 if (seeding_dev) { 2041 ret = init_first_rw_device(trans, root, device); 2042 if (ret) { 2043 btrfs_abort_transaction(trans, root, ret); 2044 goto error_trans; 2045 } 2046 ret = btrfs_finish_sprout(trans, root); 2047 if (ret) { 2048 btrfs_abort_transaction(trans, root, ret); 2049 goto error_trans; 2050 } 2051 } else { 2052 ret = btrfs_add_device(trans, root, device); 2053 if (ret) { 2054 btrfs_abort_transaction(trans, root, ret); 2055 goto error_trans; 2056 } 2057 } 2058 2059 /* 2060 * we've got more storage, clear any full flags on the space 2061 * infos 2062 */ 2063 btrfs_clear_space_info_full(root->fs_info); 2064 2065 unlock_chunks(root); 2066 root->fs_info->num_tolerated_disk_barrier_failures = 2067 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info); 2068 ret = btrfs_commit_transaction(trans, root); 2069 2070 if (seeding_dev) { 2071 mutex_unlock(&uuid_mutex); 2072 up_write(&sb->s_umount); 2073 2074 if (ret) /* transaction commit */ 2075 return ret; 2076 2077 ret = btrfs_relocate_sys_chunks(root); 2078 if (ret < 0) 2079 btrfs_error(root->fs_info, ret, 2080 "Failed to relocate sys chunks after " 2081 "device initialization. This can be fixed " 2082 "using the \"btrfs balance\" command."); 2083 trans = btrfs_attach_transaction(root); 2084 if (IS_ERR(trans)) { 2085 if (PTR_ERR(trans) == -ENOENT) 2086 return 0; 2087 return PTR_ERR(trans); 2088 } 2089 ret = btrfs_commit_transaction(trans, root); 2090 } 2091 2092 return ret; 2093 2094 error_trans: 2095 unlock_chunks(root); 2096 btrfs_end_transaction(trans, root); 2097 rcu_string_free(device->name); 2098 kfree(device); 2099 error: 2100 blkdev_put(bdev, FMODE_EXCL); 2101 if (seeding_dev) { 2102 mutex_unlock(&uuid_mutex); 2103 up_write(&sb->s_umount); 2104 } 2105 return ret; 2106 } 2107 2108 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path, 2109 struct btrfs_device **device_out) 2110 { 2111 struct request_queue *q; 2112 struct btrfs_device *device; 2113 struct block_device *bdev; 2114 struct btrfs_fs_info *fs_info = root->fs_info; 2115 struct list_head *devices; 2116 struct rcu_string *name; 2117 int ret = 0; 2118 2119 *device_out = NULL; 2120 if (fs_info->fs_devices->seeding) 2121 return -EINVAL; 2122 2123 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, 2124 fs_info->bdev_holder); 2125 if (IS_ERR(bdev)) 2126 return PTR_ERR(bdev); 2127 2128 filemap_write_and_wait(bdev->bd_inode->i_mapping); 2129 2130 devices = &fs_info->fs_devices->devices; 2131 list_for_each_entry(device, devices, dev_list) { 2132 if (device->bdev == bdev) { 2133 ret = -EEXIST; 2134 goto error; 2135 } 2136 } 2137 2138 device = kzalloc(sizeof(*device), GFP_NOFS); 2139 if (!device) { 2140 ret = -ENOMEM; 2141 goto error; 2142 } 2143 2144 name = rcu_string_strdup(device_path, GFP_NOFS); 2145 if (!name) { 2146 kfree(device); 2147 ret = -ENOMEM; 2148 goto error; 2149 } 2150 rcu_assign_pointer(device->name, name); 2151 2152 q = bdev_get_queue(bdev); 2153 if (blk_queue_discard(q)) 2154 device->can_discard = 1; 2155 mutex_lock(&root->fs_info->fs_devices->device_list_mutex); 2156 device->writeable = 1; 2157 device->work.func = pending_bios_fn; 2158 generate_random_uuid(device->uuid); 2159 device->devid = BTRFS_DEV_REPLACE_DEVID; 2160 spin_lock_init(&device->io_lock); 2161 device->generation = 0; 2162 device->io_width = root->sectorsize; 2163 device->io_align = root->sectorsize; 2164 device->sector_size = root->sectorsize; 2165 device->total_bytes = i_size_read(bdev->bd_inode); 2166 device->disk_total_bytes = device->total_bytes; 2167 device->dev_root = fs_info->dev_root; 2168 device->bdev = bdev; 2169 device->in_fs_metadata = 1; 2170 device->is_tgtdev_for_dev_replace = 1; 2171 device->mode = FMODE_EXCL; 2172 set_blocksize(device->bdev, 4096); 2173 device->fs_devices = fs_info->fs_devices; 2174 list_add(&device->dev_list, &fs_info->fs_devices->devices); 2175 fs_info->fs_devices->num_devices++; 2176 fs_info->fs_devices->open_devices++; 2177 if (device->can_discard) 2178 fs_info->fs_devices->num_can_discard++; 2179 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); 2180 2181 *device_out = device; 2182 return ret; 2183 2184 error: 2185 blkdev_put(bdev, FMODE_EXCL); 2186 return ret; 2187 } 2188 2189 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, 2190 struct btrfs_device *tgtdev) 2191 { 2192 WARN_ON(fs_info->fs_devices->rw_devices == 0); 2193 tgtdev->io_width = fs_info->dev_root->sectorsize; 2194 tgtdev->io_align = fs_info->dev_root->sectorsize; 2195 tgtdev->sector_size = fs_info->dev_root->sectorsize; 2196 tgtdev->dev_root = fs_info->dev_root; 2197 tgtdev->in_fs_metadata = 1; 2198 } 2199 2200 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, 2201 struct btrfs_device *device) 2202 { 2203 int ret; 2204 struct btrfs_path *path; 2205 struct btrfs_root *root; 2206 struct btrfs_dev_item *dev_item; 2207 struct extent_buffer *leaf; 2208 struct btrfs_key key; 2209 2210 root = device->dev_root->fs_info->chunk_root; 2211 2212 path = btrfs_alloc_path(); 2213 if (!path) 2214 return -ENOMEM; 2215 2216 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 2217 key.type = BTRFS_DEV_ITEM_KEY; 2218 key.offset = device->devid; 2219 2220 ret = btrfs_search_slot(trans, root, &key, path, 0, 1); 2221 if (ret < 0) 2222 goto out; 2223 2224 if (ret > 0) { 2225 ret = -ENOENT; 2226 goto out; 2227 } 2228 2229 leaf = path->nodes[0]; 2230 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item); 2231 2232 btrfs_set_device_id(leaf, dev_item, device->devid); 2233 btrfs_set_device_type(leaf, dev_item, device->type); 2234 btrfs_set_device_io_align(leaf, dev_item, device->io_align); 2235 btrfs_set_device_io_width(leaf, dev_item, device->io_width); 2236 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size); 2237 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes); 2238 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used); 2239 btrfs_mark_buffer_dirty(leaf); 2240 2241 out: 2242 btrfs_free_path(path); 2243 return ret; 2244 } 2245 2246 static int __btrfs_grow_device(struct btrfs_trans_handle *trans, 2247 struct btrfs_device *device, u64 new_size) 2248 { 2249 struct btrfs_super_block *super_copy = 2250 device->dev_root->fs_info->super_copy; 2251 u64 old_total = btrfs_super_total_bytes(super_copy); 2252 u64 diff = new_size - device->total_bytes; 2253 2254 if (!device->writeable) 2255 return -EACCES; 2256 if (new_size <= device->total_bytes || 2257 device->is_tgtdev_for_dev_replace) 2258 return -EINVAL; 2259 2260 btrfs_set_super_total_bytes(super_copy, old_total + diff); 2261 device->fs_devices->total_rw_bytes += diff; 2262 2263 device->total_bytes = new_size; 2264 device->disk_total_bytes = new_size; 2265 btrfs_clear_space_info_full(device->dev_root->fs_info); 2266 2267 return btrfs_update_device(trans, device); 2268 } 2269 2270 int btrfs_grow_device(struct btrfs_trans_handle *trans, 2271 struct btrfs_device *device, u64 new_size) 2272 { 2273 int ret; 2274 lock_chunks(device->dev_root); 2275 ret = __btrfs_grow_device(trans, device, new_size); 2276 unlock_chunks(device->dev_root); 2277 return ret; 2278 } 2279 2280 static int btrfs_free_chunk(struct btrfs_trans_handle *trans, 2281 struct btrfs_root *root, 2282 u64 chunk_tree, u64 chunk_objectid, 2283 u64 chunk_offset) 2284 { 2285 int ret; 2286 struct btrfs_path *path; 2287 struct btrfs_key key; 2288 2289 root = root->fs_info->chunk_root; 2290 path = btrfs_alloc_path(); 2291 if (!path) 2292 return -ENOMEM; 2293 2294 key.objectid = chunk_objectid; 2295 key.offset = chunk_offset; 2296 key.type = BTRFS_CHUNK_ITEM_KEY; 2297 2298 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2299 if (ret < 0) 2300 goto out; 2301 else if (ret > 0) { /* Logic error or corruption */ 2302 btrfs_error(root->fs_info, -ENOENT, 2303 "Failed lookup while freeing chunk."); 2304 ret = -ENOENT; 2305 goto out; 2306 } 2307 2308 ret = btrfs_del_item(trans, root, path); 2309 if (ret < 0) 2310 btrfs_error(root->fs_info, ret, 2311 "Failed to delete chunk item."); 2312 out: 2313 btrfs_free_path(path); 2314 return ret; 2315 } 2316 2317 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 2318 chunk_offset) 2319 { 2320 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 2321 struct btrfs_disk_key *disk_key; 2322 struct btrfs_chunk *chunk; 2323 u8 *ptr; 2324 int ret = 0; 2325 u32 num_stripes; 2326 u32 array_size; 2327 u32 len = 0; 2328 u32 cur; 2329 struct btrfs_key key; 2330 2331 array_size = btrfs_super_sys_array_size(super_copy); 2332 2333 ptr = super_copy->sys_chunk_array; 2334 cur = 0; 2335 2336 while (cur < array_size) { 2337 disk_key = (struct btrfs_disk_key *)ptr; 2338 btrfs_disk_key_to_cpu(&key, disk_key); 2339 2340 len = sizeof(*disk_key); 2341 2342 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 2343 chunk = (struct btrfs_chunk *)(ptr + len); 2344 num_stripes = btrfs_stack_chunk_num_stripes(chunk); 2345 len += btrfs_chunk_item_size(num_stripes); 2346 } else { 2347 ret = -EIO; 2348 break; 2349 } 2350 if (key.objectid == chunk_objectid && 2351 key.offset == chunk_offset) { 2352 memmove(ptr, ptr + len, array_size - (cur + len)); 2353 array_size -= len; 2354 btrfs_set_super_sys_array_size(super_copy, array_size); 2355 } else { 2356 ptr += len; 2357 cur += len; 2358 } 2359 } 2360 return ret; 2361 } 2362 2363 static int btrfs_relocate_chunk(struct btrfs_root *root, 2364 u64 chunk_tree, u64 chunk_objectid, 2365 u64 chunk_offset) 2366 { 2367 struct extent_map_tree *em_tree; 2368 struct btrfs_root *extent_root; 2369 struct btrfs_trans_handle *trans; 2370 struct extent_map *em; 2371 struct map_lookup *map; 2372 int ret; 2373 int i; 2374 2375 root = root->fs_info->chunk_root; 2376 extent_root = root->fs_info->extent_root; 2377 em_tree = &root->fs_info->mapping_tree.map_tree; 2378 2379 ret = btrfs_can_relocate(extent_root, chunk_offset); 2380 if (ret) 2381 return -ENOSPC; 2382 2383 /* step one, relocate all the extents inside this chunk */ 2384 ret = btrfs_relocate_block_group(extent_root, chunk_offset); 2385 if (ret) 2386 return ret; 2387 2388 trans = btrfs_start_transaction(root, 0); 2389 if (IS_ERR(trans)) { 2390 ret = PTR_ERR(trans); 2391 btrfs_std_error(root->fs_info, ret); 2392 return ret; 2393 } 2394 2395 lock_chunks(root); 2396 2397 /* 2398 * step two, delete the device extents and the 2399 * chunk tree entries 2400 */ 2401 read_lock(&em_tree->lock); 2402 em = lookup_extent_mapping(em_tree, chunk_offset, 1); 2403 read_unlock(&em_tree->lock); 2404 2405 BUG_ON(!em || em->start > chunk_offset || 2406 em->start + em->len < chunk_offset); 2407 map = (struct map_lookup *)em->bdev; 2408 2409 for (i = 0; i < map->num_stripes; i++) { 2410 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, 2411 map->stripes[i].physical); 2412 BUG_ON(ret); 2413 2414 if (map->stripes[i].dev) { 2415 ret = btrfs_update_device(trans, map->stripes[i].dev); 2416 BUG_ON(ret); 2417 } 2418 } 2419 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, 2420 chunk_offset); 2421 2422 BUG_ON(ret); 2423 2424 trace_btrfs_chunk_free(root, map, chunk_offset, em->len); 2425 2426 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 2427 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); 2428 BUG_ON(ret); 2429 } 2430 2431 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset); 2432 BUG_ON(ret); 2433 2434 write_lock(&em_tree->lock); 2435 remove_extent_mapping(em_tree, em); 2436 write_unlock(&em_tree->lock); 2437 2438 kfree(map); 2439 em->bdev = NULL; 2440 2441 /* once for the tree */ 2442 free_extent_map(em); 2443 /* once for us */ 2444 free_extent_map(em); 2445 2446 unlock_chunks(root); 2447 btrfs_end_transaction(trans, root); 2448 return 0; 2449 } 2450 2451 static int btrfs_relocate_sys_chunks(struct btrfs_root *root) 2452 { 2453 struct btrfs_root *chunk_root = root->fs_info->chunk_root; 2454 struct btrfs_path *path; 2455 struct extent_buffer *leaf; 2456 struct btrfs_chunk *chunk; 2457 struct btrfs_key key; 2458 struct btrfs_key found_key; 2459 u64 chunk_tree = chunk_root->root_key.objectid; 2460 u64 chunk_type; 2461 bool retried = false; 2462 int failed = 0; 2463 int ret; 2464 2465 path = btrfs_alloc_path(); 2466 if (!path) 2467 return -ENOMEM; 2468 2469 again: 2470 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2471 key.offset = (u64)-1; 2472 key.type = BTRFS_CHUNK_ITEM_KEY; 2473 2474 while (1) { 2475 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2476 if (ret < 0) 2477 goto error; 2478 BUG_ON(ret == 0); /* Corruption */ 2479 2480 ret = btrfs_previous_item(chunk_root, path, key.objectid, 2481 key.type); 2482 if (ret < 0) 2483 goto error; 2484 if (ret > 0) 2485 break; 2486 2487 leaf = path->nodes[0]; 2488 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); 2489 2490 chunk = btrfs_item_ptr(leaf, path->slots[0], 2491 struct btrfs_chunk); 2492 chunk_type = btrfs_chunk_type(leaf, chunk); 2493 btrfs_release_path(path); 2494 2495 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) { 2496 ret = btrfs_relocate_chunk(chunk_root, chunk_tree, 2497 found_key.objectid, 2498 found_key.offset); 2499 if (ret == -ENOSPC) 2500 failed++; 2501 else if (ret) 2502 BUG(); 2503 } 2504 2505 if (found_key.offset == 0) 2506 break; 2507 key.offset = found_key.offset - 1; 2508 } 2509 ret = 0; 2510 if (failed && !retried) { 2511 failed = 0; 2512 retried = true; 2513 goto again; 2514 } else if (failed && retried) { 2515 WARN_ON(1); 2516 ret = -ENOSPC; 2517 } 2518 error: 2519 btrfs_free_path(path); 2520 return ret; 2521 } 2522 2523 static int insert_balance_item(struct btrfs_root *root, 2524 struct btrfs_balance_control *bctl) 2525 { 2526 struct btrfs_trans_handle *trans; 2527 struct btrfs_balance_item *item; 2528 struct btrfs_disk_balance_args disk_bargs; 2529 struct btrfs_path *path; 2530 struct extent_buffer *leaf; 2531 struct btrfs_key key; 2532 int ret, err; 2533 2534 path = btrfs_alloc_path(); 2535 if (!path) 2536 return -ENOMEM; 2537 2538 trans = btrfs_start_transaction(root, 0); 2539 if (IS_ERR(trans)) { 2540 btrfs_free_path(path); 2541 return PTR_ERR(trans); 2542 } 2543 2544 key.objectid = BTRFS_BALANCE_OBJECTID; 2545 key.type = BTRFS_BALANCE_ITEM_KEY; 2546 key.offset = 0; 2547 2548 ret = btrfs_insert_empty_item(trans, root, path, &key, 2549 sizeof(*item)); 2550 if (ret) 2551 goto out; 2552 2553 leaf = path->nodes[0]; 2554 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 2555 2556 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); 2557 2558 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data); 2559 btrfs_set_balance_data(leaf, item, &disk_bargs); 2560 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta); 2561 btrfs_set_balance_meta(leaf, item, &disk_bargs); 2562 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys); 2563 btrfs_set_balance_sys(leaf, item, &disk_bargs); 2564 2565 btrfs_set_balance_flags(leaf, item, bctl->flags); 2566 2567 btrfs_mark_buffer_dirty(leaf); 2568 out: 2569 btrfs_free_path(path); 2570 err = btrfs_commit_transaction(trans, root); 2571 if (err && !ret) 2572 ret = err; 2573 return ret; 2574 } 2575 2576 static int del_balance_item(struct btrfs_root *root) 2577 { 2578 struct btrfs_trans_handle *trans; 2579 struct btrfs_path *path; 2580 struct btrfs_key key; 2581 int ret, err; 2582 2583 path = btrfs_alloc_path(); 2584 if (!path) 2585 return -ENOMEM; 2586 2587 trans = btrfs_start_transaction(root, 0); 2588 if (IS_ERR(trans)) { 2589 btrfs_free_path(path); 2590 return PTR_ERR(trans); 2591 } 2592 2593 key.objectid = BTRFS_BALANCE_OBJECTID; 2594 key.type = BTRFS_BALANCE_ITEM_KEY; 2595 key.offset = 0; 2596 2597 ret = btrfs_search_slot(trans, root, &key, path, -1, 1); 2598 if (ret < 0) 2599 goto out; 2600 if (ret > 0) { 2601 ret = -ENOENT; 2602 goto out; 2603 } 2604 2605 ret = btrfs_del_item(trans, root, path); 2606 out: 2607 btrfs_free_path(path); 2608 err = btrfs_commit_transaction(trans, root); 2609 if (err && !ret) 2610 ret = err; 2611 return ret; 2612 } 2613 2614 /* 2615 * This is a heuristic used to reduce the number of chunks balanced on 2616 * resume after balance was interrupted. 2617 */ 2618 static void update_balance_args(struct btrfs_balance_control *bctl) 2619 { 2620 /* 2621 * Turn on soft mode for chunk types that were being converted. 2622 */ 2623 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) 2624 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT; 2625 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) 2626 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT; 2627 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) 2628 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT; 2629 2630 /* 2631 * Turn on usage filter if is not already used. The idea is 2632 * that chunks that we have already balanced should be 2633 * reasonably full. Don't do it for chunks that are being 2634 * converted - that will keep us from relocating unconverted 2635 * (albeit full) chunks. 2636 */ 2637 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) && 2638 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2639 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE; 2640 bctl->data.usage = 90; 2641 } 2642 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) && 2643 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2644 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE; 2645 bctl->sys.usage = 90; 2646 } 2647 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) && 2648 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) { 2649 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE; 2650 bctl->meta.usage = 90; 2651 } 2652 } 2653 2654 /* 2655 * Should be called with both balance and volume mutexes held to 2656 * serialize other volume operations (add_dev/rm_dev/resize) with 2657 * restriper. Same goes for unset_balance_control. 2658 */ 2659 static void set_balance_control(struct btrfs_balance_control *bctl) 2660 { 2661 struct btrfs_fs_info *fs_info = bctl->fs_info; 2662 2663 BUG_ON(fs_info->balance_ctl); 2664 2665 spin_lock(&fs_info->balance_lock); 2666 fs_info->balance_ctl = bctl; 2667 spin_unlock(&fs_info->balance_lock); 2668 } 2669 2670 static void unset_balance_control(struct btrfs_fs_info *fs_info) 2671 { 2672 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2673 2674 BUG_ON(!fs_info->balance_ctl); 2675 2676 spin_lock(&fs_info->balance_lock); 2677 fs_info->balance_ctl = NULL; 2678 spin_unlock(&fs_info->balance_lock); 2679 2680 kfree(bctl); 2681 } 2682 2683 /* 2684 * Balance filters. Return 1 if chunk should be filtered out 2685 * (should not be balanced). 2686 */ 2687 static int chunk_profiles_filter(u64 chunk_type, 2688 struct btrfs_balance_args *bargs) 2689 { 2690 chunk_type = chunk_to_extended(chunk_type) & 2691 BTRFS_EXTENDED_PROFILE_MASK; 2692 2693 if (bargs->profiles & chunk_type) 2694 return 0; 2695 2696 return 1; 2697 } 2698 2699 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset, 2700 struct btrfs_balance_args *bargs) 2701 { 2702 struct btrfs_block_group_cache *cache; 2703 u64 chunk_used, user_thresh; 2704 int ret = 1; 2705 2706 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 2707 chunk_used = btrfs_block_group_used(&cache->item); 2708 2709 if (bargs->usage == 0) 2710 user_thresh = 1; 2711 else if (bargs->usage > 100) 2712 user_thresh = cache->key.offset; 2713 else 2714 user_thresh = div_factor_fine(cache->key.offset, 2715 bargs->usage); 2716 2717 if (chunk_used < user_thresh) 2718 ret = 0; 2719 2720 btrfs_put_block_group(cache); 2721 return ret; 2722 } 2723 2724 static int chunk_devid_filter(struct extent_buffer *leaf, 2725 struct btrfs_chunk *chunk, 2726 struct btrfs_balance_args *bargs) 2727 { 2728 struct btrfs_stripe *stripe; 2729 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2730 int i; 2731 2732 for (i = 0; i < num_stripes; i++) { 2733 stripe = btrfs_stripe_nr(chunk, i); 2734 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid) 2735 return 0; 2736 } 2737 2738 return 1; 2739 } 2740 2741 /* [pstart, pend) */ 2742 static int chunk_drange_filter(struct extent_buffer *leaf, 2743 struct btrfs_chunk *chunk, 2744 u64 chunk_offset, 2745 struct btrfs_balance_args *bargs) 2746 { 2747 struct btrfs_stripe *stripe; 2748 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 2749 u64 stripe_offset; 2750 u64 stripe_length; 2751 int factor; 2752 int i; 2753 2754 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID)) 2755 return 0; 2756 2757 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP | 2758 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) { 2759 factor = num_stripes / 2; 2760 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) { 2761 factor = num_stripes - 1; 2762 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) { 2763 factor = num_stripes - 2; 2764 } else { 2765 factor = num_stripes; 2766 } 2767 2768 for (i = 0; i < num_stripes; i++) { 2769 stripe = btrfs_stripe_nr(chunk, i); 2770 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid) 2771 continue; 2772 2773 stripe_offset = btrfs_stripe_offset(leaf, stripe); 2774 stripe_length = btrfs_chunk_length(leaf, chunk); 2775 do_div(stripe_length, factor); 2776 2777 if (stripe_offset < bargs->pend && 2778 stripe_offset + stripe_length > bargs->pstart) 2779 return 0; 2780 } 2781 2782 return 1; 2783 } 2784 2785 /* [vstart, vend) */ 2786 static int chunk_vrange_filter(struct extent_buffer *leaf, 2787 struct btrfs_chunk *chunk, 2788 u64 chunk_offset, 2789 struct btrfs_balance_args *bargs) 2790 { 2791 if (chunk_offset < bargs->vend && 2792 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart) 2793 /* at least part of the chunk is inside this vrange */ 2794 return 0; 2795 2796 return 1; 2797 } 2798 2799 static int chunk_soft_convert_filter(u64 chunk_type, 2800 struct btrfs_balance_args *bargs) 2801 { 2802 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT)) 2803 return 0; 2804 2805 chunk_type = chunk_to_extended(chunk_type) & 2806 BTRFS_EXTENDED_PROFILE_MASK; 2807 2808 if (bargs->target == chunk_type) 2809 return 1; 2810 2811 return 0; 2812 } 2813 2814 static int should_balance_chunk(struct btrfs_root *root, 2815 struct extent_buffer *leaf, 2816 struct btrfs_chunk *chunk, u64 chunk_offset) 2817 { 2818 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl; 2819 struct btrfs_balance_args *bargs = NULL; 2820 u64 chunk_type = btrfs_chunk_type(leaf, chunk); 2821 2822 /* type filter */ 2823 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) & 2824 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) { 2825 return 0; 2826 } 2827 2828 if (chunk_type & BTRFS_BLOCK_GROUP_DATA) 2829 bargs = &bctl->data; 2830 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) 2831 bargs = &bctl->sys; 2832 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA) 2833 bargs = &bctl->meta; 2834 2835 /* profiles filter */ 2836 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) && 2837 chunk_profiles_filter(chunk_type, bargs)) { 2838 return 0; 2839 } 2840 2841 /* usage filter */ 2842 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) && 2843 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) { 2844 return 0; 2845 } 2846 2847 /* devid filter */ 2848 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) && 2849 chunk_devid_filter(leaf, chunk, bargs)) { 2850 return 0; 2851 } 2852 2853 /* drange filter, makes sense only with devid filter */ 2854 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) && 2855 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) { 2856 return 0; 2857 } 2858 2859 /* vrange filter */ 2860 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) && 2861 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) { 2862 return 0; 2863 } 2864 2865 /* soft profile changing mode */ 2866 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) && 2867 chunk_soft_convert_filter(chunk_type, bargs)) { 2868 return 0; 2869 } 2870 2871 return 1; 2872 } 2873 2874 static int __btrfs_balance(struct btrfs_fs_info *fs_info) 2875 { 2876 struct btrfs_balance_control *bctl = fs_info->balance_ctl; 2877 struct btrfs_root *chunk_root = fs_info->chunk_root; 2878 struct btrfs_root *dev_root = fs_info->dev_root; 2879 struct list_head *devices; 2880 struct btrfs_device *device; 2881 u64 old_size; 2882 u64 size_to_free; 2883 struct btrfs_chunk *chunk; 2884 struct btrfs_path *path; 2885 struct btrfs_key key; 2886 struct btrfs_key found_key; 2887 struct btrfs_trans_handle *trans; 2888 struct extent_buffer *leaf; 2889 int slot; 2890 int ret; 2891 int enospc_errors = 0; 2892 bool counting = true; 2893 2894 /* step one make some room on all the devices */ 2895 devices = &fs_info->fs_devices->devices; 2896 list_for_each_entry(device, devices, dev_list) { 2897 old_size = device->total_bytes; 2898 size_to_free = div_factor(old_size, 1); 2899 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024); 2900 if (!device->writeable || 2901 device->total_bytes - device->bytes_used > size_to_free || 2902 device->is_tgtdev_for_dev_replace) 2903 continue; 2904 2905 ret = btrfs_shrink_device(device, old_size - size_to_free); 2906 if (ret == -ENOSPC) 2907 break; 2908 BUG_ON(ret); 2909 2910 trans = btrfs_start_transaction(dev_root, 0); 2911 BUG_ON(IS_ERR(trans)); 2912 2913 ret = btrfs_grow_device(trans, device, old_size); 2914 BUG_ON(ret); 2915 2916 btrfs_end_transaction(trans, dev_root); 2917 } 2918 2919 /* step two, relocate all the chunks */ 2920 path = btrfs_alloc_path(); 2921 if (!path) { 2922 ret = -ENOMEM; 2923 goto error; 2924 } 2925 2926 /* zero out stat counters */ 2927 spin_lock(&fs_info->balance_lock); 2928 memset(&bctl->stat, 0, sizeof(bctl->stat)); 2929 spin_unlock(&fs_info->balance_lock); 2930 again: 2931 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 2932 key.offset = (u64)-1; 2933 key.type = BTRFS_CHUNK_ITEM_KEY; 2934 2935 while (1) { 2936 if ((!counting && atomic_read(&fs_info->balance_pause_req)) || 2937 atomic_read(&fs_info->balance_cancel_req)) { 2938 ret = -ECANCELED; 2939 goto error; 2940 } 2941 2942 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0); 2943 if (ret < 0) 2944 goto error; 2945 2946 /* 2947 * this shouldn't happen, it means the last relocate 2948 * failed 2949 */ 2950 if (ret == 0) 2951 BUG(); /* FIXME break ? */ 2952 2953 ret = btrfs_previous_item(chunk_root, path, 0, 2954 BTRFS_CHUNK_ITEM_KEY); 2955 if (ret) { 2956 ret = 0; 2957 break; 2958 } 2959 2960 leaf = path->nodes[0]; 2961 slot = path->slots[0]; 2962 btrfs_item_key_to_cpu(leaf, &found_key, slot); 2963 2964 if (found_key.objectid != key.objectid) 2965 break; 2966 2967 /* chunk zero is special */ 2968 if (found_key.offset == 0) 2969 break; 2970 2971 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 2972 2973 if (!counting) { 2974 spin_lock(&fs_info->balance_lock); 2975 bctl->stat.considered++; 2976 spin_unlock(&fs_info->balance_lock); 2977 } 2978 2979 ret = should_balance_chunk(chunk_root, leaf, chunk, 2980 found_key.offset); 2981 btrfs_release_path(path); 2982 if (!ret) 2983 goto loop; 2984 2985 if (counting) { 2986 spin_lock(&fs_info->balance_lock); 2987 bctl->stat.expected++; 2988 spin_unlock(&fs_info->balance_lock); 2989 goto loop; 2990 } 2991 2992 ret = btrfs_relocate_chunk(chunk_root, 2993 chunk_root->root_key.objectid, 2994 found_key.objectid, 2995 found_key.offset); 2996 if (ret && ret != -ENOSPC) 2997 goto error; 2998 if (ret == -ENOSPC) { 2999 enospc_errors++; 3000 } else { 3001 spin_lock(&fs_info->balance_lock); 3002 bctl->stat.completed++; 3003 spin_unlock(&fs_info->balance_lock); 3004 } 3005 loop: 3006 key.offset = found_key.offset - 1; 3007 } 3008 3009 if (counting) { 3010 btrfs_release_path(path); 3011 counting = false; 3012 goto again; 3013 } 3014 error: 3015 btrfs_free_path(path); 3016 if (enospc_errors) { 3017 printk(KERN_INFO "btrfs: %d enospc errors during balance\n", 3018 enospc_errors); 3019 if (!ret) 3020 ret = -ENOSPC; 3021 } 3022 3023 return ret; 3024 } 3025 3026 /** 3027 * alloc_profile_is_valid - see if a given profile is valid and reduced 3028 * @flags: profile to validate 3029 * @extended: if true @flags is treated as an extended profile 3030 */ 3031 static int alloc_profile_is_valid(u64 flags, int extended) 3032 { 3033 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK : 3034 BTRFS_BLOCK_GROUP_PROFILE_MASK); 3035 3036 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK; 3037 3038 /* 1) check that all other bits are zeroed */ 3039 if (flags & ~mask) 3040 return 0; 3041 3042 /* 2) see if profile is reduced */ 3043 if (flags == 0) 3044 return !extended; /* "0" is valid for usual profiles */ 3045 3046 /* true if exactly one bit set */ 3047 return (flags & (flags - 1)) == 0; 3048 } 3049 3050 static inline int balance_need_close(struct btrfs_fs_info *fs_info) 3051 { 3052 /* cancel requested || normal exit path */ 3053 return atomic_read(&fs_info->balance_cancel_req) || 3054 (atomic_read(&fs_info->balance_pause_req) == 0 && 3055 atomic_read(&fs_info->balance_cancel_req) == 0); 3056 } 3057 3058 static void __cancel_balance(struct btrfs_fs_info *fs_info) 3059 { 3060 int ret; 3061 3062 unset_balance_control(fs_info); 3063 ret = del_balance_item(fs_info->tree_root); 3064 if (ret) 3065 btrfs_std_error(fs_info, ret); 3066 3067 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3068 } 3069 3070 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock, 3071 struct btrfs_ioctl_balance_args *bargs); 3072 3073 /* 3074 * Should be called with both balance and volume mutexes held 3075 */ 3076 int btrfs_balance(struct btrfs_balance_control *bctl, 3077 struct btrfs_ioctl_balance_args *bargs) 3078 { 3079 struct btrfs_fs_info *fs_info = bctl->fs_info; 3080 u64 allowed; 3081 int mixed = 0; 3082 int ret; 3083 u64 num_devices; 3084 unsigned seq; 3085 3086 if (btrfs_fs_closing(fs_info) || 3087 atomic_read(&fs_info->balance_pause_req) || 3088 atomic_read(&fs_info->balance_cancel_req)) { 3089 ret = -EINVAL; 3090 goto out; 3091 } 3092 3093 allowed = btrfs_super_incompat_flags(fs_info->super_copy); 3094 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) 3095 mixed = 1; 3096 3097 /* 3098 * In case of mixed groups both data and meta should be picked, 3099 * and identical options should be given for both of them. 3100 */ 3101 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA; 3102 if (mixed && (bctl->flags & allowed)) { 3103 if (!(bctl->flags & BTRFS_BALANCE_DATA) || 3104 !(bctl->flags & BTRFS_BALANCE_METADATA) || 3105 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) { 3106 printk(KERN_ERR "btrfs: with mixed groups data and " 3107 "metadata balance options must be the same\n"); 3108 ret = -EINVAL; 3109 goto out; 3110 } 3111 } 3112 3113 num_devices = fs_info->fs_devices->num_devices; 3114 btrfs_dev_replace_lock(&fs_info->dev_replace); 3115 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) { 3116 BUG_ON(num_devices < 1); 3117 num_devices--; 3118 } 3119 btrfs_dev_replace_unlock(&fs_info->dev_replace); 3120 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE; 3121 if (num_devices == 1) 3122 allowed |= BTRFS_BLOCK_GROUP_DUP; 3123 else if (num_devices < 4) 3124 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1); 3125 else 3126 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 | 3127 BTRFS_BLOCK_GROUP_RAID10 | 3128 BTRFS_BLOCK_GROUP_RAID5 | 3129 BTRFS_BLOCK_GROUP_RAID6); 3130 3131 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3132 (!alloc_profile_is_valid(bctl->data.target, 1) || 3133 (bctl->data.target & ~allowed))) { 3134 printk(KERN_ERR "btrfs: unable to start balance with target " 3135 "data profile %llu\n", 3136 (unsigned long long)bctl->data.target); 3137 ret = -EINVAL; 3138 goto out; 3139 } 3140 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3141 (!alloc_profile_is_valid(bctl->meta.target, 1) || 3142 (bctl->meta.target & ~allowed))) { 3143 printk(KERN_ERR "btrfs: unable to start balance with target " 3144 "metadata profile %llu\n", 3145 (unsigned long long)bctl->meta.target); 3146 ret = -EINVAL; 3147 goto out; 3148 } 3149 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3150 (!alloc_profile_is_valid(bctl->sys.target, 1) || 3151 (bctl->sys.target & ~allowed))) { 3152 printk(KERN_ERR "btrfs: unable to start balance with target " 3153 "system profile %llu\n", 3154 (unsigned long long)bctl->sys.target); 3155 ret = -EINVAL; 3156 goto out; 3157 } 3158 3159 /* allow dup'ed data chunks only in mixed mode */ 3160 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3161 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) { 3162 printk(KERN_ERR "btrfs: dup for data is not allowed\n"); 3163 ret = -EINVAL; 3164 goto out; 3165 } 3166 3167 /* allow to reduce meta or sys integrity only if force set */ 3168 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 | 3169 BTRFS_BLOCK_GROUP_RAID10 | 3170 BTRFS_BLOCK_GROUP_RAID5 | 3171 BTRFS_BLOCK_GROUP_RAID6; 3172 do { 3173 seq = read_seqbegin(&fs_info->profiles_lock); 3174 3175 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3176 (fs_info->avail_system_alloc_bits & allowed) && 3177 !(bctl->sys.target & allowed)) || 3178 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) && 3179 (fs_info->avail_metadata_alloc_bits & allowed) && 3180 !(bctl->meta.target & allowed))) { 3181 if (bctl->flags & BTRFS_BALANCE_FORCE) { 3182 printk(KERN_INFO "btrfs: force reducing metadata " 3183 "integrity\n"); 3184 } else { 3185 printk(KERN_ERR "btrfs: balance will reduce metadata " 3186 "integrity, use force if you want this\n"); 3187 ret = -EINVAL; 3188 goto out; 3189 } 3190 } 3191 } while (read_seqretry(&fs_info->profiles_lock, seq)); 3192 3193 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3194 int num_tolerated_disk_barrier_failures; 3195 u64 target = bctl->sys.target; 3196 3197 num_tolerated_disk_barrier_failures = 3198 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3199 if (num_tolerated_disk_barrier_failures > 0 && 3200 (target & 3201 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 | 3202 BTRFS_AVAIL_ALLOC_BIT_SINGLE))) 3203 num_tolerated_disk_barrier_failures = 0; 3204 else if (num_tolerated_disk_barrier_failures > 1 && 3205 (target & 3206 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10))) 3207 num_tolerated_disk_barrier_failures = 1; 3208 3209 fs_info->num_tolerated_disk_barrier_failures = 3210 num_tolerated_disk_barrier_failures; 3211 } 3212 3213 ret = insert_balance_item(fs_info->tree_root, bctl); 3214 if (ret && ret != -EEXIST) 3215 goto out; 3216 3217 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) { 3218 BUG_ON(ret == -EEXIST); 3219 set_balance_control(bctl); 3220 } else { 3221 BUG_ON(ret != -EEXIST); 3222 spin_lock(&fs_info->balance_lock); 3223 update_balance_args(bctl); 3224 spin_unlock(&fs_info->balance_lock); 3225 } 3226 3227 atomic_inc(&fs_info->balance_running); 3228 mutex_unlock(&fs_info->balance_mutex); 3229 3230 ret = __btrfs_balance(fs_info); 3231 3232 mutex_lock(&fs_info->balance_mutex); 3233 atomic_dec(&fs_info->balance_running); 3234 3235 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) { 3236 fs_info->num_tolerated_disk_barrier_failures = 3237 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info); 3238 } 3239 3240 if (bargs) { 3241 memset(bargs, 0, sizeof(*bargs)); 3242 update_ioctl_balance_args(fs_info, 0, bargs); 3243 } 3244 3245 if ((ret && ret != -ECANCELED && ret != -ENOSPC) || 3246 balance_need_close(fs_info)) { 3247 __cancel_balance(fs_info); 3248 } 3249 3250 wake_up(&fs_info->balance_wait_q); 3251 3252 return ret; 3253 out: 3254 if (bctl->flags & BTRFS_BALANCE_RESUME) 3255 __cancel_balance(fs_info); 3256 else { 3257 kfree(bctl); 3258 atomic_set(&fs_info->mutually_exclusive_operation_running, 0); 3259 } 3260 return ret; 3261 } 3262 3263 static int balance_kthread(void *data) 3264 { 3265 struct btrfs_fs_info *fs_info = data; 3266 int ret = 0; 3267 3268 mutex_lock(&fs_info->volume_mutex); 3269 mutex_lock(&fs_info->balance_mutex); 3270 3271 if (fs_info->balance_ctl) { 3272 printk(KERN_INFO "btrfs: continuing balance\n"); 3273 ret = btrfs_balance(fs_info->balance_ctl, NULL); 3274 } 3275 3276 mutex_unlock(&fs_info->balance_mutex); 3277 mutex_unlock(&fs_info->volume_mutex); 3278 3279 return ret; 3280 } 3281 3282 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info) 3283 { 3284 struct task_struct *tsk; 3285 3286 spin_lock(&fs_info->balance_lock); 3287 if (!fs_info->balance_ctl) { 3288 spin_unlock(&fs_info->balance_lock); 3289 return 0; 3290 } 3291 spin_unlock(&fs_info->balance_lock); 3292 3293 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) { 3294 printk(KERN_INFO "btrfs: force skipping balance\n"); 3295 return 0; 3296 } 3297 3298 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance"); 3299 if (IS_ERR(tsk)) 3300 return PTR_ERR(tsk); 3301 3302 return 0; 3303 } 3304 3305 int btrfs_recover_balance(struct btrfs_fs_info *fs_info) 3306 { 3307 struct btrfs_balance_control *bctl; 3308 struct btrfs_balance_item *item; 3309 struct btrfs_disk_balance_args disk_bargs; 3310 struct btrfs_path *path; 3311 struct extent_buffer *leaf; 3312 struct btrfs_key key; 3313 int ret; 3314 3315 path = btrfs_alloc_path(); 3316 if (!path) 3317 return -ENOMEM; 3318 3319 key.objectid = BTRFS_BALANCE_OBJECTID; 3320 key.type = BTRFS_BALANCE_ITEM_KEY; 3321 key.offset = 0; 3322 3323 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); 3324 if (ret < 0) 3325 goto out; 3326 if (ret > 0) { /* ret = -ENOENT; */ 3327 ret = 0; 3328 goto out; 3329 } 3330 3331 bctl = kzalloc(sizeof(*bctl), GFP_NOFS); 3332 if (!bctl) { 3333 ret = -ENOMEM; 3334 goto out; 3335 } 3336 3337 leaf = path->nodes[0]; 3338 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item); 3339 3340 bctl->fs_info = fs_info; 3341 bctl->flags = btrfs_balance_flags(leaf, item); 3342 bctl->flags |= BTRFS_BALANCE_RESUME; 3343 3344 btrfs_balance_data(leaf, item, &disk_bargs); 3345 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs); 3346 btrfs_balance_meta(leaf, item, &disk_bargs); 3347 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs); 3348 btrfs_balance_sys(leaf, item, &disk_bargs); 3349 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs); 3350 3351 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)); 3352 3353 mutex_lock(&fs_info->volume_mutex); 3354 mutex_lock(&fs_info->balance_mutex); 3355 3356 set_balance_control(bctl); 3357 3358 mutex_unlock(&fs_info->balance_mutex); 3359 mutex_unlock(&fs_info->volume_mutex); 3360 out: 3361 btrfs_free_path(path); 3362 return ret; 3363 } 3364 3365 int btrfs_pause_balance(struct btrfs_fs_info *fs_info) 3366 { 3367 int ret = 0; 3368 3369 mutex_lock(&fs_info->balance_mutex); 3370 if (!fs_info->balance_ctl) { 3371 mutex_unlock(&fs_info->balance_mutex); 3372 return -ENOTCONN; 3373 } 3374 3375 if (atomic_read(&fs_info->balance_running)) { 3376 atomic_inc(&fs_info->balance_pause_req); 3377 mutex_unlock(&fs_info->balance_mutex); 3378 3379 wait_event(fs_info->balance_wait_q, 3380 atomic_read(&fs_info->balance_running) == 0); 3381 3382 mutex_lock(&fs_info->balance_mutex); 3383 /* we are good with balance_ctl ripped off from under us */ 3384 BUG_ON(atomic_read(&fs_info->balance_running)); 3385 atomic_dec(&fs_info->balance_pause_req); 3386 } else { 3387 ret = -ENOTCONN; 3388 } 3389 3390 mutex_unlock(&fs_info->balance_mutex); 3391 return ret; 3392 } 3393 3394 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info) 3395 { 3396 mutex_lock(&fs_info->balance_mutex); 3397 if (!fs_info->balance_ctl) { 3398 mutex_unlock(&fs_info->balance_mutex); 3399 return -ENOTCONN; 3400 } 3401 3402 atomic_inc(&fs_info->balance_cancel_req); 3403 /* 3404 * if we are running just wait and return, balance item is 3405 * deleted in btrfs_balance in this case 3406 */ 3407 if (atomic_read(&fs_info->balance_running)) { 3408 mutex_unlock(&fs_info->balance_mutex); 3409 wait_event(fs_info->balance_wait_q, 3410 atomic_read(&fs_info->balance_running) == 0); 3411 mutex_lock(&fs_info->balance_mutex); 3412 } else { 3413 /* __cancel_balance needs volume_mutex */ 3414 mutex_unlock(&fs_info->balance_mutex); 3415 mutex_lock(&fs_info->volume_mutex); 3416 mutex_lock(&fs_info->balance_mutex); 3417 3418 if (fs_info->balance_ctl) 3419 __cancel_balance(fs_info); 3420 3421 mutex_unlock(&fs_info->volume_mutex); 3422 } 3423 3424 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running)); 3425 atomic_dec(&fs_info->balance_cancel_req); 3426 mutex_unlock(&fs_info->balance_mutex); 3427 return 0; 3428 } 3429 3430 /* 3431 * shrinking a device means finding all of the device extents past 3432 * the new size, and then following the back refs to the chunks. 3433 * The chunk relocation code actually frees the device extent 3434 */ 3435 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) 3436 { 3437 struct btrfs_trans_handle *trans; 3438 struct btrfs_root *root = device->dev_root; 3439 struct btrfs_dev_extent *dev_extent = NULL; 3440 struct btrfs_path *path; 3441 u64 length; 3442 u64 chunk_tree; 3443 u64 chunk_objectid; 3444 u64 chunk_offset; 3445 int ret; 3446 int slot; 3447 int failed = 0; 3448 bool retried = false; 3449 struct extent_buffer *l; 3450 struct btrfs_key key; 3451 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3452 u64 old_total = btrfs_super_total_bytes(super_copy); 3453 u64 old_size = device->total_bytes; 3454 u64 diff = device->total_bytes - new_size; 3455 3456 if (device->is_tgtdev_for_dev_replace) 3457 return -EINVAL; 3458 3459 path = btrfs_alloc_path(); 3460 if (!path) 3461 return -ENOMEM; 3462 3463 path->reada = 2; 3464 3465 lock_chunks(root); 3466 3467 device->total_bytes = new_size; 3468 if (device->writeable) { 3469 device->fs_devices->total_rw_bytes -= diff; 3470 spin_lock(&root->fs_info->free_chunk_lock); 3471 root->fs_info->free_chunk_space -= diff; 3472 spin_unlock(&root->fs_info->free_chunk_lock); 3473 } 3474 unlock_chunks(root); 3475 3476 again: 3477 key.objectid = device->devid; 3478 key.offset = (u64)-1; 3479 key.type = BTRFS_DEV_EXTENT_KEY; 3480 3481 do { 3482 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3483 if (ret < 0) 3484 goto done; 3485 3486 ret = btrfs_previous_item(root, path, 0, key.type); 3487 if (ret < 0) 3488 goto done; 3489 if (ret) { 3490 ret = 0; 3491 btrfs_release_path(path); 3492 break; 3493 } 3494 3495 l = path->nodes[0]; 3496 slot = path->slots[0]; 3497 btrfs_item_key_to_cpu(l, &key, path->slots[0]); 3498 3499 if (key.objectid != device->devid) { 3500 btrfs_release_path(path); 3501 break; 3502 } 3503 3504 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 3505 length = btrfs_dev_extent_length(l, dev_extent); 3506 3507 if (key.offset + length <= new_size) { 3508 btrfs_release_path(path); 3509 break; 3510 } 3511 3512 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); 3513 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); 3514 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); 3515 btrfs_release_path(path); 3516 3517 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, 3518 chunk_offset); 3519 if (ret && ret != -ENOSPC) 3520 goto done; 3521 if (ret == -ENOSPC) 3522 failed++; 3523 } while (key.offset-- > 0); 3524 3525 if (failed && !retried) { 3526 failed = 0; 3527 retried = true; 3528 goto again; 3529 } else if (failed && retried) { 3530 ret = -ENOSPC; 3531 lock_chunks(root); 3532 3533 device->total_bytes = old_size; 3534 if (device->writeable) 3535 device->fs_devices->total_rw_bytes += diff; 3536 spin_lock(&root->fs_info->free_chunk_lock); 3537 root->fs_info->free_chunk_space += diff; 3538 spin_unlock(&root->fs_info->free_chunk_lock); 3539 unlock_chunks(root); 3540 goto done; 3541 } 3542 3543 /* Shrinking succeeded, else we would be at "done". */ 3544 trans = btrfs_start_transaction(root, 0); 3545 if (IS_ERR(trans)) { 3546 ret = PTR_ERR(trans); 3547 goto done; 3548 } 3549 3550 lock_chunks(root); 3551 3552 device->disk_total_bytes = new_size; 3553 /* Now btrfs_update_device() will change the on-disk size. */ 3554 ret = btrfs_update_device(trans, device); 3555 if (ret) { 3556 unlock_chunks(root); 3557 btrfs_end_transaction(trans, root); 3558 goto done; 3559 } 3560 WARN_ON(diff > old_total); 3561 btrfs_set_super_total_bytes(super_copy, old_total - diff); 3562 unlock_chunks(root); 3563 btrfs_end_transaction(trans, root); 3564 done: 3565 btrfs_free_path(path); 3566 return ret; 3567 } 3568 3569 static int btrfs_add_system_chunk(struct btrfs_root *root, 3570 struct btrfs_key *key, 3571 struct btrfs_chunk *chunk, int item_size) 3572 { 3573 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 3574 struct btrfs_disk_key disk_key; 3575 u32 array_size; 3576 u8 *ptr; 3577 3578 array_size = btrfs_super_sys_array_size(super_copy); 3579 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) 3580 return -EFBIG; 3581 3582 ptr = super_copy->sys_chunk_array + array_size; 3583 btrfs_cpu_key_to_disk(&disk_key, key); 3584 memcpy(ptr, &disk_key, sizeof(disk_key)); 3585 ptr += sizeof(disk_key); 3586 memcpy(ptr, chunk, item_size); 3587 item_size += sizeof(disk_key); 3588 btrfs_set_super_sys_array_size(super_copy, array_size + item_size); 3589 return 0; 3590 } 3591 3592 /* 3593 * sort the devices in descending order by max_avail, total_avail 3594 */ 3595 static int btrfs_cmp_device_info(const void *a, const void *b) 3596 { 3597 const struct btrfs_device_info *di_a = a; 3598 const struct btrfs_device_info *di_b = b; 3599 3600 if (di_a->max_avail > di_b->max_avail) 3601 return -1; 3602 if (di_a->max_avail < di_b->max_avail) 3603 return 1; 3604 if (di_a->total_avail > di_b->total_avail) 3605 return -1; 3606 if (di_a->total_avail < di_b->total_avail) 3607 return 1; 3608 return 0; 3609 } 3610 3611 static struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { 3612 [BTRFS_RAID_RAID10] = { 3613 .sub_stripes = 2, 3614 .dev_stripes = 1, 3615 .devs_max = 0, /* 0 == as many as possible */ 3616 .devs_min = 4, 3617 .devs_increment = 2, 3618 .ncopies = 2, 3619 }, 3620 [BTRFS_RAID_RAID1] = { 3621 .sub_stripes = 1, 3622 .dev_stripes = 1, 3623 .devs_max = 2, 3624 .devs_min = 2, 3625 .devs_increment = 2, 3626 .ncopies = 2, 3627 }, 3628 [BTRFS_RAID_DUP] = { 3629 .sub_stripes = 1, 3630 .dev_stripes = 2, 3631 .devs_max = 1, 3632 .devs_min = 1, 3633 .devs_increment = 1, 3634 .ncopies = 2, 3635 }, 3636 [BTRFS_RAID_RAID0] = { 3637 .sub_stripes = 1, 3638 .dev_stripes = 1, 3639 .devs_max = 0, 3640 .devs_min = 2, 3641 .devs_increment = 1, 3642 .ncopies = 1, 3643 }, 3644 [BTRFS_RAID_SINGLE] = { 3645 .sub_stripes = 1, 3646 .dev_stripes = 1, 3647 .devs_max = 1, 3648 .devs_min = 1, 3649 .devs_increment = 1, 3650 .ncopies = 1, 3651 }, 3652 [BTRFS_RAID_RAID5] = { 3653 .sub_stripes = 1, 3654 .dev_stripes = 1, 3655 .devs_max = 0, 3656 .devs_min = 2, 3657 .devs_increment = 1, 3658 .ncopies = 2, 3659 }, 3660 [BTRFS_RAID_RAID6] = { 3661 .sub_stripes = 1, 3662 .dev_stripes = 1, 3663 .devs_max = 0, 3664 .devs_min = 3, 3665 .devs_increment = 1, 3666 .ncopies = 3, 3667 }, 3668 }; 3669 3670 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target) 3671 { 3672 /* TODO allow them to set a preferred stripe size */ 3673 return 64 * 1024; 3674 } 3675 3676 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type) 3677 { 3678 if (!(type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6))) 3679 return; 3680 3681 btrfs_set_fs_incompat(info, RAID56); 3682 } 3683 3684 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 3685 struct btrfs_root *extent_root, 3686 struct map_lookup **map_ret, 3687 u64 *num_bytes_out, u64 *stripe_size_out, 3688 u64 start, u64 type) 3689 { 3690 struct btrfs_fs_info *info = extent_root->fs_info; 3691 struct btrfs_fs_devices *fs_devices = info->fs_devices; 3692 struct list_head *cur; 3693 struct map_lookup *map = NULL; 3694 struct extent_map_tree *em_tree; 3695 struct extent_map *em; 3696 struct btrfs_device_info *devices_info = NULL; 3697 u64 total_avail; 3698 int num_stripes; /* total number of stripes to allocate */ 3699 int data_stripes; /* number of stripes that count for 3700 block group size */ 3701 int sub_stripes; /* sub_stripes info for map */ 3702 int dev_stripes; /* stripes per dev */ 3703 int devs_max; /* max devs to use */ 3704 int devs_min; /* min devs needed */ 3705 int devs_increment; /* ndevs has to be a multiple of this */ 3706 int ncopies; /* how many copies to data has */ 3707 int ret; 3708 u64 max_stripe_size; 3709 u64 max_chunk_size; 3710 u64 stripe_size; 3711 u64 num_bytes; 3712 u64 raid_stripe_len = BTRFS_STRIPE_LEN; 3713 int ndevs; 3714 int i; 3715 int j; 3716 int index; 3717 3718 BUG_ON(!alloc_profile_is_valid(type, 0)); 3719 3720 if (list_empty(&fs_devices->alloc_list)) 3721 return -ENOSPC; 3722 3723 index = __get_raid_index(type); 3724 3725 sub_stripes = btrfs_raid_array[index].sub_stripes; 3726 dev_stripes = btrfs_raid_array[index].dev_stripes; 3727 devs_max = btrfs_raid_array[index].devs_max; 3728 devs_min = btrfs_raid_array[index].devs_min; 3729 devs_increment = btrfs_raid_array[index].devs_increment; 3730 ncopies = btrfs_raid_array[index].ncopies; 3731 3732 if (type & BTRFS_BLOCK_GROUP_DATA) { 3733 max_stripe_size = 1024 * 1024 * 1024; 3734 max_chunk_size = 10 * max_stripe_size; 3735 } else if (type & BTRFS_BLOCK_GROUP_METADATA) { 3736 /* for larger filesystems, use larger metadata chunks */ 3737 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024) 3738 max_stripe_size = 1024 * 1024 * 1024; 3739 else 3740 max_stripe_size = 256 * 1024 * 1024; 3741 max_chunk_size = max_stripe_size; 3742 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) { 3743 max_stripe_size = 32 * 1024 * 1024; 3744 max_chunk_size = 2 * max_stripe_size; 3745 } else { 3746 printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n", 3747 type); 3748 BUG_ON(1); 3749 } 3750 3751 /* we don't want a chunk larger than 10% of writeable space */ 3752 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1), 3753 max_chunk_size); 3754 3755 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices, 3756 GFP_NOFS); 3757 if (!devices_info) 3758 return -ENOMEM; 3759 3760 cur = fs_devices->alloc_list.next; 3761 3762 /* 3763 * in the first pass through the devices list, we gather information 3764 * about the available holes on each device. 3765 */ 3766 ndevs = 0; 3767 while (cur != &fs_devices->alloc_list) { 3768 struct btrfs_device *device; 3769 u64 max_avail; 3770 u64 dev_offset; 3771 3772 device = list_entry(cur, struct btrfs_device, dev_alloc_list); 3773 3774 cur = cur->next; 3775 3776 if (!device->writeable) { 3777 WARN(1, KERN_ERR 3778 "btrfs: read-only device in alloc_list\n"); 3779 continue; 3780 } 3781 3782 if (!device->in_fs_metadata || 3783 device->is_tgtdev_for_dev_replace) 3784 continue; 3785 3786 if (device->total_bytes > device->bytes_used) 3787 total_avail = device->total_bytes - device->bytes_used; 3788 else 3789 total_avail = 0; 3790 3791 /* If there is no space on this device, skip it. */ 3792 if (total_avail == 0) 3793 continue; 3794 3795 ret = find_free_dev_extent(device, 3796 max_stripe_size * dev_stripes, 3797 &dev_offset, &max_avail); 3798 if (ret && ret != -ENOSPC) 3799 goto error; 3800 3801 if (ret == 0) 3802 max_avail = max_stripe_size * dev_stripes; 3803 3804 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes) 3805 continue; 3806 3807 if (ndevs == fs_devices->rw_devices) { 3808 WARN(1, "%s: found more than %llu devices\n", 3809 __func__, fs_devices->rw_devices); 3810 break; 3811 } 3812 devices_info[ndevs].dev_offset = dev_offset; 3813 devices_info[ndevs].max_avail = max_avail; 3814 devices_info[ndevs].total_avail = total_avail; 3815 devices_info[ndevs].dev = device; 3816 ++ndevs; 3817 } 3818 3819 /* 3820 * now sort the devices by hole size / available space 3821 */ 3822 sort(devices_info, ndevs, sizeof(struct btrfs_device_info), 3823 btrfs_cmp_device_info, NULL); 3824 3825 /* round down to number of usable stripes */ 3826 ndevs -= ndevs % devs_increment; 3827 3828 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) { 3829 ret = -ENOSPC; 3830 goto error; 3831 } 3832 3833 if (devs_max && ndevs > devs_max) 3834 ndevs = devs_max; 3835 /* 3836 * the primary goal is to maximize the number of stripes, so use as many 3837 * devices as possible, even if the stripes are not maximum sized. 3838 */ 3839 stripe_size = devices_info[ndevs-1].max_avail; 3840 num_stripes = ndevs * dev_stripes; 3841 3842 /* 3843 * this will have to be fixed for RAID1 and RAID10 over 3844 * more drives 3845 */ 3846 data_stripes = num_stripes / ncopies; 3847 3848 if (type & BTRFS_BLOCK_GROUP_RAID5) { 3849 raid_stripe_len = find_raid56_stripe_len(ndevs - 1, 3850 btrfs_super_stripesize(info->super_copy)); 3851 data_stripes = num_stripes - 1; 3852 } 3853 if (type & BTRFS_BLOCK_GROUP_RAID6) { 3854 raid_stripe_len = find_raid56_stripe_len(ndevs - 2, 3855 btrfs_super_stripesize(info->super_copy)); 3856 data_stripes = num_stripes - 2; 3857 } 3858 3859 /* 3860 * Use the number of data stripes to figure out how big this chunk 3861 * is really going to be in terms of logical address space, 3862 * and compare that answer with the max chunk size 3863 */ 3864 if (stripe_size * data_stripes > max_chunk_size) { 3865 u64 mask = (1ULL << 24) - 1; 3866 stripe_size = max_chunk_size; 3867 do_div(stripe_size, data_stripes); 3868 3869 /* bump the answer up to a 16MB boundary */ 3870 stripe_size = (stripe_size + mask) & ~mask; 3871 3872 /* but don't go higher than the limits we found 3873 * while searching for free extents 3874 */ 3875 if (stripe_size > devices_info[ndevs-1].max_avail) 3876 stripe_size = devices_info[ndevs-1].max_avail; 3877 } 3878 3879 do_div(stripe_size, dev_stripes); 3880 3881 /* align to BTRFS_STRIPE_LEN */ 3882 do_div(stripe_size, raid_stripe_len); 3883 stripe_size *= raid_stripe_len; 3884 3885 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 3886 if (!map) { 3887 ret = -ENOMEM; 3888 goto error; 3889 } 3890 map->num_stripes = num_stripes; 3891 3892 for (i = 0; i < ndevs; ++i) { 3893 for (j = 0; j < dev_stripes; ++j) { 3894 int s = i * dev_stripes + j; 3895 map->stripes[s].dev = devices_info[i].dev; 3896 map->stripes[s].physical = devices_info[i].dev_offset + 3897 j * stripe_size; 3898 } 3899 } 3900 map->sector_size = extent_root->sectorsize; 3901 map->stripe_len = raid_stripe_len; 3902 map->io_align = raid_stripe_len; 3903 map->io_width = raid_stripe_len; 3904 map->type = type; 3905 map->sub_stripes = sub_stripes; 3906 3907 *map_ret = map; 3908 num_bytes = stripe_size * data_stripes; 3909 3910 *stripe_size_out = stripe_size; 3911 *num_bytes_out = num_bytes; 3912 3913 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes); 3914 3915 em = alloc_extent_map(); 3916 if (!em) { 3917 ret = -ENOMEM; 3918 goto error; 3919 } 3920 em->bdev = (struct block_device *)map; 3921 em->start = start; 3922 em->len = num_bytes; 3923 em->block_start = 0; 3924 em->block_len = em->len; 3925 3926 em_tree = &extent_root->fs_info->mapping_tree.map_tree; 3927 write_lock(&em_tree->lock); 3928 ret = add_extent_mapping(em_tree, em, 0); 3929 write_unlock(&em_tree->lock); 3930 if (ret) { 3931 free_extent_map(em); 3932 goto error; 3933 } 3934 3935 for (i = 0; i < map->num_stripes; ++i) { 3936 struct btrfs_device *device; 3937 u64 dev_offset; 3938 3939 device = map->stripes[i].dev; 3940 dev_offset = map->stripes[i].physical; 3941 3942 ret = btrfs_alloc_dev_extent(trans, device, 3943 info->chunk_root->root_key.objectid, 3944 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3945 start, dev_offset, stripe_size); 3946 if (ret) 3947 goto error_dev_extent; 3948 } 3949 3950 ret = btrfs_make_block_group(trans, extent_root, 0, type, 3951 BTRFS_FIRST_CHUNK_TREE_OBJECTID, 3952 start, num_bytes); 3953 if (ret) { 3954 i = map->num_stripes - 1; 3955 goto error_dev_extent; 3956 } 3957 3958 free_extent_map(em); 3959 check_raid56_incompat_flag(extent_root->fs_info, type); 3960 3961 kfree(devices_info); 3962 return 0; 3963 3964 error_dev_extent: 3965 for (; i >= 0; i--) { 3966 struct btrfs_device *device; 3967 int err; 3968 3969 device = map->stripes[i].dev; 3970 err = btrfs_free_dev_extent(trans, device, start); 3971 if (err) { 3972 btrfs_abort_transaction(trans, extent_root, err); 3973 break; 3974 } 3975 } 3976 write_lock(&em_tree->lock); 3977 remove_extent_mapping(em_tree, em); 3978 write_unlock(&em_tree->lock); 3979 3980 /* One for our allocation */ 3981 free_extent_map(em); 3982 /* One for the tree reference */ 3983 free_extent_map(em); 3984 error: 3985 kfree(map); 3986 kfree(devices_info); 3987 return ret; 3988 } 3989 3990 static int __finish_chunk_alloc(struct btrfs_trans_handle *trans, 3991 struct btrfs_root *extent_root, 3992 struct map_lookup *map, u64 chunk_offset, 3993 u64 chunk_size, u64 stripe_size) 3994 { 3995 u64 dev_offset; 3996 struct btrfs_key key; 3997 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 3998 struct btrfs_device *device; 3999 struct btrfs_chunk *chunk; 4000 struct btrfs_stripe *stripe; 4001 size_t item_size = btrfs_chunk_item_size(map->num_stripes); 4002 int index = 0; 4003 int ret; 4004 4005 chunk = kzalloc(item_size, GFP_NOFS); 4006 if (!chunk) 4007 return -ENOMEM; 4008 4009 index = 0; 4010 while (index < map->num_stripes) { 4011 device = map->stripes[index].dev; 4012 device->bytes_used += stripe_size; 4013 ret = btrfs_update_device(trans, device); 4014 if (ret) 4015 goto out_free; 4016 index++; 4017 } 4018 4019 spin_lock(&extent_root->fs_info->free_chunk_lock); 4020 extent_root->fs_info->free_chunk_space -= (stripe_size * 4021 map->num_stripes); 4022 spin_unlock(&extent_root->fs_info->free_chunk_lock); 4023 4024 index = 0; 4025 stripe = &chunk->stripe; 4026 while (index < map->num_stripes) { 4027 device = map->stripes[index].dev; 4028 dev_offset = map->stripes[index].physical; 4029 4030 btrfs_set_stack_stripe_devid(stripe, device->devid); 4031 btrfs_set_stack_stripe_offset(stripe, dev_offset); 4032 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE); 4033 stripe++; 4034 index++; 4035 } 4036 4037 btrfs_set_stack_chunk_length(chunk, chunk_size); 4038 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid); 4039 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len); 4040 btrfs_set_stack_chunk_type(chunk, map->type); 4041 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes); 4042 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len); 4043 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len); 4044 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize); 4045 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes); 4046 4047 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; 4048 key.type = BTRFS_CHUNK_ITEM_KEY; 4049 key.offset = chunk_offset; 4050 4051 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size); 4052 4053 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) { 4054 /* 4055 * TODO: Cleanup of inserted chunk root in case of 4056 * failure. 4057 */ 4058 ret = btrfs_add_system_chunk(chunk_root, &key, chunk, 4059 item_size); 4060 } 4061 4062 out_free: 4063 kfree(chunk); 4064 return ret; 4065 } 4066 4067 /* 4068 * Chunk allocation falls into two parts. The first part does works 4069 * that make the new allocated chunk useable, but not do any operation 4070 * that modifies the chunk tree. The second part does the works that 4071 * require modifying the chunk tree. This division is important for the 4072 * bootstrap process of adding storage to a seed btrfs. 4073 */ 4074 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 4075 struct btrfs_root *extent_root, u64 type) 4076 { 4077 u64 chunk_offset; 4078 u64 chunk_size; 4079 u64 stripe_size; 4080 struct map_lookup *map; 4081 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; 4082 int ret; 4083 4084 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, 4085 &chunk_offset); 4086 if (ret) 4087 return ret; 4088 4089 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, 4090 &stripe_size, chunk_offset, type); 4091 if (ret) 4092 return ret; 4093 4094 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, 4095 chunk_size, stripe_size); 4096 if (ret) 4097 return ret; 4098 return 0; 4099 } 4100 4101 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans, 4102 struct btrfs_root *root, 4103 struct btrfs_device *device) 4104 { 4105 u64 chunk_offset; 4106 u64 sys_chunk_offset; 4107 u64 chunk_size; 4108 u64 sys_chunk_size; 4109 u64 stripe_size; 4110 u64 sys_stripe_size; 4111 u64 alloc_profile; 4112 struct map_lookup *map; 4113 struct map_lookup *sys_map; 4114 struct btrfs_fs_info *fs_info = root->fs_info; 4115 struct btrfs_root *extent_root = fs_info->extent_root; 4116 int ret; 4117 4118 ret = find_next_chunk(fs_info->chunk_root, 4119 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset); 4120 if (ret) 4121 return ret; 4122 4123 alloc_profile = btrfs_get_alloc_profile(extent_root, 0); 4124 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size, 4125 &stripe_size, chunk_offset, alloc_profile); 4126 if (ret) 4127 return ret; 4128 4129 sys_chunk_offset = chunk_offset + chunk_size; 4130 4131 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0); 4132 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map, 4133 &sys_chunk_size, &sys_stripe_size, 4134 sys_chunk_offset, alloc_profile); 4135 if (ret) { 4136 btrfs_abort_transaction(trans, root, ret); 4137 goto out; 4138 } 4139 4140 ret = btrfs_add_device(trans, fs_info->chunk_root, device); 4141 if (ret) { 4142 btrfs_abort_transaction(trans, root, ret); 4143 goto out; 4144 } 4145 4146 /* 4147 * Modifying chunk tree needs allocating new blocks from both 4148 * system block group and metadata block group. So we only can 4149 * do operations require modifying the chunk tree after both 4150 * block groups were created. 4151 */ 4152 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset, 4153 chunk_size, stripe_size); 4154 if (ret) { 4155 btrfs_abort_transaction(trans, root, ret); 4156 goto out; 4157 } 4158 4159 ret = __finish_chunk_alloc(trans, extent_root, sys_map, 4160 sys_chunk_offset, sys_chunk_size, 4161 sys_stripe_size); 4162 if (ret) 4163 btrfs_abort_transaction(trans, root, ret); 4164 4165 out: 4166 4167 return ret; 4168 } 4169 4170 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset) 4171 { 4172 struct extent_map *em; 4173 struct map_lookup *map; 4174 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 4175 int readonly = 0; 4176 int i; 4177 4178 read_lock(&map_tree->map_tree.lock); 4179 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); 4180 read_unlock(&map_tree->map_tree.lock); 4181 if (!em) 4182 return 1; 4183 4184 if (btrfs_test_opt(root, DEGRADED)) { 4185 free_extent_map(em); 4186 return 0; 4187 } 4188 4189 map = (struct map_lookup *)em->bdev; 4190 for (i = 0; i < map->num_stripes; i++) { 4191 if (!map->stripes[i].dev->writeable) { 4192 readonly = 1; 4193 break; 4194 } 4195 } 4196 free_extent_map(em); 4197 return readonly; 4198 } 4199 4200 void btrfs_mapping_init(struct btrfs_mapping_tree *tree) 4201 { 4202 extent_map_tree_init(&tree->map_tree); 4203 } 4204 4205 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree) 4206 { 4207 struct extent_map *em; 4208 4209 while (1) { 4210 write_lock(&tree->map_tree.lock); 4211 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1); 4212 if (em) 4213 remove_extent_mapping(&tree->map_tree, em); 4214 write_unlock(&tree->map_tree.lock); 4215 if (!em) 4216 break; 4217 kfree(em->bdev); 4218 /* once for us */ 4219 free_extent_map(em); 4220 /* once for the tree */ 4221 free_extent_map(em); 4222 } 4223 } 4224 4225 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) 4226 { 4227 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4228 struct extent_map *em; 4229 struct map_lookup *map; 4230 struct extent_map_tree *em_tree = &map_tree->map_tree; 4231 int ret; 4232 4233 read_lock(&em_tree->lock); 4234 em = lookup_extent_mapping(em_tree, logical, len); 4235 read_unlock(&em_tree->lock); 4236 4237 /* 4238 * We could return errors for these cases, but that could get ugly and 4239 * we'd probably do the same thing which is just not do anything else 4240 * and exit, so return 1 so the callers don't try to use other copies. 4241 */ 4242 if (!em) { 4243 btrfs_emerg(fs_info, "No mapping for %Lu-%Lu\n", logical, 4244 logical+len); 4245 return 1; 4246 } 4247 4248 if (em->start > logical || em->start + em->len < logical) { 4249 btrfs_emerg(fs_info, "Invalid mapping for %Lu-%Lu, got " 4250 "%Lu-%Lu\n", logical, logical+len, em->start, 4251 em->start + em->len); 4252 return 1; 4253 } 4254 4255 map = (struct map_lookup *)em->bdev; 4256 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1)) 4257 ret = map->num_stripes; 4258 else if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4259 ret = map->sub_stripes; 4260 else if (map->type & BTRFS_BLOCK_GROUP_RAID5) 4261 ret = 2; 4262 else if (map->type & BTRFS_BLOCK_GROUP_RAID6) 4263 ret = 3; 4264 else 4265 ret = 1; 4266 free_extent_map(em); 4267 4268 btrfs_dev_replace_lock(&fs_info->dev_replace); 4269 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) 4270 ret++; 4271 btrfs_dev_replace_unlock(&fs_info->dev_replace); 4272 4273 return ret; 4274 } 4275 4276 unsigned long btrfs_full_stripe_len(struct btrfs_root *root, 4277 struct btrfs_mapping_tree *map_tree, 4278 u64 logical) 4279 { 4280 struct extent_map *em; 4281 struct map_lookup *map; 4282 struct extent_map_tree *em_tree = &map_tree->map_tree; 4283 unsigned long len = root->sectorsize; 4284 4285 read_lock(&em_tree->lock); 4286 em = lookup_extent_mapping(em_tree, logical, len); 4287 read_unlock(&em_tree->lock); 4288 BUG_ON(!em); 4289 4290 BUG_ON(em->start > logical || em->start + em->len < logical); 4291 map = (struct map_lookup *)em->bdev; 4292 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4293 BTRFS_BLOCK_GROUP_RAID6)) { 4294 len = map->stripe_len * nr_data_stripes(map); 4295 } 4296 free_extent_map(em); 4297 return len; 4298 } 4299 4300 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree, 4301 u64 logical, u64 len, int mirror_num) 4302 { 4303 struct extent_map *em; 4304 struct map_lookup *map; 4305 struct extent_map_tree *em_tree = &map_tree->map_tree; 4306 int ret = 0; 4307 4308 read_lock(&em_tree->lock); 4309 em = lookup_extent_mapping(em_tree, logical, len); 4310 read_unlock(&em_tree->lock); 4311 BUG_ON(!em); 4312 4313 BUG_ON(em->start > logical || em->start + em->len < logical); 4314 map = (struct map_lookup *)em->bdev; 4315 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4316 BTRFS_BLOCK_GROUP_RAID6)) 4317 ret = 1; 4318 free_extent_map(em); 4319 return ret; 4320 } 4321 4322 static int find_live_mirror(struct btrfs_fs_info *fs_info, 4323 struct map_lookup *map, int first, int num, 4324 int optimal, int dev_replace_is_ongoing) 4325 { 4326 int i; 4327 int tolerance; 4328 struct btrfs_device *srcdev; 4329 4330 if (dev_replace_is_ongoing && 4331 fs_info->dev_replace.cont_reading_from_srcdev_mode == 4332 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID) 4333 srcdev = fs_info->dev_replace.srcdev; 4334 else 4335 srcdev = NULL; 4336 4337 /* 4338 * try to avoid the drive that is the source drive for a 4339 * dev-replace procedure, only choose it if no other non-missing 4340 * mirror is available 4341 */ 4342 for (tolerance = 0; tolerance < 2; tolerance++) { 4343 if (map->stripes[optimal].dev->bdev && 4344 (tolerance || map->stripes[optimal].dev != srcdev)) 4345 return optimal; 4346 for (i = first; i < first + num; i++) { 4347 if (map->stripes[i].dev->bdev && 4348 (tolerance || map->stripes[i].dev != srcdev)) 4349 return i; 4350 } 4351 } 4352 4353 /* we couldn't find one that doesn't fail. Just return something 4354 * and the io error handling code will clean up eventually 4355 */ 4356 return optimal; 4357 } 4358 4359 static inline int parity_smaller(u64 a, u64 b) 4360 { 4361 return a > b; 4362 } 4363 4364 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */ 4365 static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map) 4366 { 4367 struct btrfs_bio_stripe s; 4368 int i; 4369 u64 l; 4370 int again = 1; 4371 4372 while (again) { 4373 again = 0; 4374 for (i = 0; i < bbio->num_stripes - 1; i++) { 4375 if (parity_smaller(raid_map[i], raid_map[i+1])) { 4376 s = bbio->stripes[i]; 4377 l = raid_map[i]; 4378 bbio->stripes[i] = bbio->stripes[i+1]; 4379 raid_map[i] = raid_map[i+1]; 4380 bbio->stripes[i+1] = s; 4381 raid_map[i+1] = l; 4382 again = 1; 4383 } 4384 } 4385 } 4386 } 4387 4388 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4389 u64 logical, u64 *length, 4390 struct btrfs_bio **bbio_ret, 4391 int mirror_num, u64 **raid_map_ret) 4392 { 4393 struct extent_map *em; 4394 struct map_lookup *map; 4395 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; 4396 struct extent_map_tree *em_tree = &map_tree->map_tree; 4397 u64 offset; 4398 u64 stripe_offset; 4399 u64 stripe_end_offset; 4400 u64 stripe_nr; 4401 u64 stripe_nr_orig; 4402 u64 stripe_nr_end; 4403 u64 stripe_len; 4404 u64 *raid_map = NULL; 4405 int stripe_index; 4406 int i; 4407 int ret = 0; 4408 int num_stripes; 4409 int max_errors = 0; 4410 struct btrfs_bio *bbio = NULL; 4411 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 4412 int dev_replace_is_ongoing = 0; 4413 int num_alloc_stripes; 4414 int patch_the_first_stripe_for_dev_replace = 0; 4415 u64 physical_to_patch_in_first_stripe = 0; 4416 u64 raid56_full_stripe_start = (u64)-1; 4417 4418 read_lock(&em_tree->lock); 4419 em = lookup_extent_mapping(em_tree, logical, *length); 4420 read_unlock(&em_tree->lock); 4421 4422 if (!em) { 4423 btrfs_crit(fs_info, "unable to find logical %llu len %llu", 4424 (unsigned long long)logical, 4425 (unsigned long long)*length); 4426 return -EINVAL; 4427 } 4428 4429 if (em->start > logical || em->start + em->len < logical) { 4430 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, " 4431 "found %Lu-%Lu\n", logical, em->start, 4432 em->start + em->len); 4433 return -EINVAL; 4434 } 4435 4436 map = (struct map_lookup *)em->bdev; 4437 offset = logical - em->start; 4438 4439 if (mirror_num > map->num_stripes) 4440 mirror_num = 0; 4441 4442 stripe_len = map->stripe_len; 4443 stripe_nr = offset; 4444 /* 4445 * stripe_nr counts the total number of stripes we have to stride 4446 * to get to this block 4447 */ 4448 do_div(stripe_nr, stripe_len); 4449 4450 stripe_offset = stripe_nr * stripe_len; 4451 BUG_ON(offset < stripe_offset); 4452 4453 /* stripe_offset is the offset of this block in its stripe*/ 4454 stripe_offset = offset - stripe_offset; 4455 4456 /* if we're here for raid56, we need to know the stripe aligned start */ 4457 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { 4458 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map); 4459 raid56_full_stripe_start = offset; 4460 4461 /* allow a write of a full stripe, but make sure we don't 4462 * allow straddling of stripes 4463 */ 4464 do_div(raid56_full_stripe_start, full_stripe_len); 4465 raid56_full_stripe_start *= full_stripe_len; 4466 } 4467 4468 if (rw & REQ_DISCARD) { 4469 /* we don't discard raid56 yet */ 4470 if (map->type & 4471 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) { 4472 ret = -EOPNOTSUPP; 4473 goto out; 4474 } 4475 *length = min_t(u64, em->len - offset, *length); 4476 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) { 4477 u64 max_len; 4478 /* For writes to RAID[56], allow a full stripeset across all disks. 4479 For other RAID types and for RAID[56] reads, just allow a single 4480 stripe (on a single disk). */ 4481 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6) && 4482 (rw & REQ_WRITE)) { 4483 max_len = stripe_len * nr_data_stripes(map) - 4484 (offset - raid56_full_stripe_start); 4485 } else { 4486 /* we limit the length of each bio to what fits in a stripe */ 4487 max_len = stripe_len - stripe_offset; 4488 } 4489 *length = min_t(u64, em->len - offset, max_len); 4490 } else { 4491 *length = em->len - offset; 4492 } 4493 4494 /* This is for when we're called from btrfs_merge_bio_hook() and all 4495 it cares about is the length */ 4496 if (!bbio_ret) 4497 goto out; 4498 4499 btrfs_dev_replace_lock(dev_replace); 4500 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace); 4501 if (!dev_replace_is_ongoing) 4502 btrfs_dev_replace_unlock(dev_replace); 4503 4504 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 && 4505 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) && 4506 dev_replace->tgtdev != NULL) { 4507 /* 4508 * in dev-replace case, for repair case (that's the only 4509 * case where the mirror is selected explicitly when 4510 * calling btrfs_map_block), blocks left of the left cursor 4511 * can also be read from the target drive. 4512 * For REQ_GET_READ_MIRRORS, the target drive is added as 4513 * the last one to the array of stripes. For READ, it also 4514 * needs to be supported using the same mirror number. 4515 * If the requested block is not left of the left cursor, 4516 * EIO is returned. This can happen because btrfs_num_copies() 4517 * returns one more in the dev-replace case. 4518 */ 4519 u64 tmp_length = *length; 4520 struct btrfs_bio *tmp_bbio = NULL; 4521 int tmp_num_stripes; 4522 u64 srcdev_devid = dev_replace->srcdev->devid; 4523 int index_srcdev = 0; 4524 int found = 0; 4525 u64 physical_of_found = 0; 4526 4527 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, 4528 logical, &tmp_length, &tmp_bbio, 0, NULL); 4529 if (ret) { 4530 WARN_ON(tmp_bbio != NULL); 4531 goto out; 4532 } 4533 4534 tmp_num_stripes = tmp_bbio->num_stripes; 4535 if (mirror_num > tmp_num_stripes) { 4536 /* 4537 * REQ_GET_READ_MIRRORS does not contain this 4538 * mirror, that means that the requested area 4539 * is not left of the left cursor 4540 */ 4541 ret = -EIO; 4542 kfree(tmp_bbio); 4543 goto out; 4544 } 4545 4546 /* 4547 * process the rest of the function using the mirror_num 4548 * of the source drive. Therefore look it up first. 4549 * At the end, patch the device pointer to the one of the 4550 * target drive. 4551 */ 4552 for (i = 0; i < tmp_num_stripes; i++) { 4553 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) { 4554 /* 4555 * In case of DUP, in order to keep it 4556 * simple, only add the mirror with the 4557 * lowest physical address 4558 */ 4559 if (found && 4560 physical_of_found <= 4561 tmp_bbio->stripes[i].physical) 4562 continue; 4563 index_srcdev = i; 4564 found = 1; 4565 physical_of_found = 4566 tmp_bbio->stripes[i].physical; 4567 } 4568 } 4569 4570 if (found) { 4571 mirror_num = index_srcdev + 1; 4572 patch_the_first_stripe_for_dev_replace = 1; 4573 physical_to_patch_in_first_stripe = physical_of_found; 4574 } else { 4575 WARN_ON(1); 4576 ret = -EIO; 4577 kfree(tmp_bbio); 4578 goto out; 4579 } 4580 4581 kfree(tmp_bbio); 4582 } else if (mirror_num > map->num_stripes) { 4583 mirror_num = 0; 4584 } 4585 4586 num_stripes = 1; 4587 stripe_index = 0; 4588 stripe_nr_orig = stripe_nr; 4589 stripe_nr_end = ALIGN(offset + *length, map->stripe_len); 4590 do_div(stripe_nr_end, map->stripe_len); 4591 stripe_end_offset = stripe_nr_end * map->stripe_len - 4592 (offset + *length); 4593 4594 if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4595 if (rw & REQ_DISCARD) 4596 num_stripes = min_t(u64, map->num_stripes, 4597 stripe_nr_end - stripe_nr_orig); 4598 stripe_index = do_div(stripe_nr, map->num_stripes); 4599 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { 4600 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) 4601 num_stripes = map->num_stripes; 4602 else if (mirror_num) 4603 stripe_index = mirror_num - 1; 4604 else { 4605 stripe_index = find_live_mirror(fs_info, map, 0, 4606 map->num_stripes, 4607 current->pid % map->num_stripes, 4608 dev_replace_is_ongoing); 4609 mirror_num = stripe_index + 1; 4610 } 4611 4612 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { 4613 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) { 4614 num_stripes = map->num_stripes; 4615 } else if (mirror_num) { 4616 stripe_index = mirror_num - 1; 4617 } else { 4618 mirror_num = 1; 4619 } 4620 4621 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4622 int factor = map->num_stripes / map->sub_stripes; 4623 4624 stripe_index = do_div(stripe_nr, factor); 4625 stripe_index *= map->sub_stripes; 4626 4627 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) 4628 num_stripes = map->sub_stripes; 4629 else if (rw & REQ_DISCARD) 4630 num_stripes = min_t(u64, map->sub_stripes * 4631 (stripe_nr_end - stripe_nr_orig), 4632 map->num_stripes); 4633 else if (mirror_num) 4634 stripe_index += mirror_num - 1; 4635 else { 4636 int old_stripe_index = stripe_index; 4637 stripe_index = find_live_mirror(fs_info, map, 4638 stripe_index, 4639 map->sub_stripes, stripe_index + 4640 current->pid % map->sub_stripes, 4641 dev_replace_is_ongoing); 4642 mirror_num = stripe_index - old_stripe_index + 1; 4643 } 4644 4645 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4646 BTRFS_BLOCK_GROUP_RAID6)) { 4647 u64 tmp; 4648 4649 if (bbio_ret && ((rw & REQ_WRITE) || mirror_num > 1) 4650 && raid_map_ret) { 4651 int i, rot; 4652 4653 /* push stripe_nr back to the start of the full stripe */ 4654 stripe_nr = raid56_full_stripe_start; 4655 do_div(stripe_nr, stripe_len); 4656 4657 stripe_index = do_div(stripe_nr, nr_data_stripes(map)); 4658 4659 /* RAID[56] write or recovery. Return all stripes */ 4660 num_stripes = map->num_stripes; 4661 max_errors = nr_parity_stripes(map); 4662 4663 raid_map = kmalloc(sizeof(u64) * num_stripes, 4664 GFP_NOFS); 4665 if (!raid_map) { 4666 ret = -ENOMEM; 4667 goto out; 4668 } 4669 4670 /* Work out the disk rotation on this stripe-set */ 4671 tmp = stripe_nr; 4672 rot = do_div(tmp, num_stripes); 4673 4674 /* Fill in the logical address of each stripe */ 4675 tmp = stripe_nr * nr_data_stripes(map); 4676 for (i = 0; i < nr_data_stripes(map); i++) 4677 raid_map[(i+rot) % num_stripes] = 4678 em->start + (tmp + i) * map->stripe_len; 4679 4680 raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE; 4681 if (map->type & BTRFS_BLOCK_GROUP_RAID6) 4682 raid_map[(i+rot+1) % num_stripes] = 4683 RAID6_Q_STRIPE; 4684 4685 *length = map->stripe_len; 4686 stripe_index = 0; 4687 stripe_offset = 0; 4688 } else { 4689 /* 4690 * Mirror #0 or #1 means the original data block. 4691 * Mirror #2 is RAID5 parity block. 4692 * Mirror #3 is RAID6 Q block. 4693 */ 4694 stripe_index = do_div(stripe_nr, nr_data_stripes(map)); 4695 if (mirror_num > 1) 4696 stripe_index = nr_data_stripes(map) + 4697 mirror_num - 2; 4698 4699 /* We distribute the parity blocks across stripes */ 4700 tmp = stripe_nr + stripe_index; 4701 stripe_index = do_div(tmp, map->num_stripes); 4702 } 4703 } else { 4704 /* 4705 * after this do_div call, stripe_nr is the number of stripes 4706 * on this device we have to walk to find the data, and 4707 * stripe_index is the number of our device in the stripe array 4708 */ 4709 stripe_index = do_div(stripe_nr, map->num_stripes); 4710 mirror_num = stripe_index + 1; 4711 } 4712 BUG_ON(stripe_index >= map->num_stripes); 4713 4714 num_alloc_stripes = num_stripes; 4715 if (dev_replace_is_ongoing) { 4716 if (rw & (REQ_WRITE | REQ_DISCARD)) 4717 num_alloc_stripes <<= 1; 4718 if (rw & REQ_GET_READ_MIRRORS) 4719 num_alloc_stripes++; 4720 } 4721 bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS); 4722 if (!bbio) { 4723 ret = -ENOMEM; 4724 goto out; 4725 } 4726 atomic_set(&bbio->error, 0); 4727 4728 if (rw & REQ_DISCARD) { 4729 int factor = 0; 4730 int sub_stripes = 0; 4731 u64 stripes_per_dev = 0; 4732 u32 remaining_stripes = 0; 4733 u32 last_stripe = 0; 4734 4735 if (map->type & 4736 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { 4737 if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4738 sub_stripes = 1; 4739 else 4740 sub_stripes = map->sub_stripes; 4741 4742 factor = map->num_stripes / sub_stripes; 4743 stripes_per_dev = div_u64_rem(stripe_nr_end - 4744 stripe_nr_orig, 4745 factor, 4746 &remaining_stripes); 4747 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe); 4748 last_stripe *= sub_stripes; 4749 } 4750 4751 for (i = 0; i < num_stripes; i++) { 4752 bbio->stripes[i].physical = 4753 map->stripes[stripe_index].physical + 4754 stripe_offset + stripe_nr * map->stripe_len; 4755 bbio->stripes[i].dev = map->stripes[stripe_index].dev; 4756 4757 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 | 4758 BTRFS_BLOCK_GROUP_RAID10)) { 4759 bbio->stripes[i].length = stripes_per_dev * 4760 map->stripe_len; 4761 4762 if (i / sub_stripes < remaining_stripes) 4763 bbio->stripes[i].length += 4764 map->stripe_len; 4765 4766 /* 4767 * Special for the first stripe and 4768 * the last stripe: 4769 * 4770 * |-------|...|-------| 4771 * |----------| 4772 * off end_off 4773 */ 4774 if (i < sub_stripes) 4775 bbio->stripes[i].length -= 4776 stripe_offset; 4777 4778 if (stripe_index >= last_stripe && 4779 stripe_index <= (last_stripe + 4780 sub_stripes - 1)) 4781 bbio->stripes[i].length -= 4782 stripe_end_offset; 4783 4784 if (i == sub_stripes - 1) 4785 stripe_offset = 0; 4786 } else 4787 bbio->stripes[i].length = *length; 4788 4789 stripe_index++; 4790 if (stripe_index == map->num_stripes) { 4791 /* This could only happen for RAID0/10 */ 4792 stripe_index = 0; 4793 stripe_nr++; 4794 } 4795 } 4796 } else { 4797 for (i = 0; i < num_stripes; i++) { 4798 bbio->stripes[i].physical = 4799 map->stripes[stripe_index].physical + 4800 stripe_offset + 4801 stripe_nr * map->stripe_len; 4802 bbio->stripes[i].dev = 4803 map->stripes[stripe_index].dev; 4804 stripe_index++; 4805 } 4806 } 4807 4808 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) { 4809 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 | 4810 BTRFS_BLOCK_GROUP_RAID10 | 4811 BTRFS_BLOCK_GROUP_RAID5 | 4812 BTRFS_BLOCK_GROUP_DUP)) { 4813 max_errors = 1; 4814 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) { 4815 max_errors = 2; 4816 } 4817 } 4818 4819 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) && 4820 dev_replace->tgtdev != NULL) { 4821 int index_where_to_add; 4822 u64 srcdev_devid = dev_replace->srcdev->devid; 4823 4824 /* 4825 * duplicate the write operations while the dev replace 4826 * procedure is running. Since the copying of the old disk 4827 * to the new disk takes place at run time while the 4828 * filesystem is mounted writable, the regular write 4829 * operations to the old disk have to be duplicated to go 4830 * to the new disk as well. 4831 * Note that device->missing is handled by the caller, and 4832 * that the write to the old disk is already set up in the 4833 * stripes array. 4834 */ 4835 index_where_to_add = num_stripes; 4836 for (i = 0; i < num_stripes; i++) { 4837 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4838 /* write to new disk, too */ 4839 struct btrfs_bio_stripe *new = 4840 bbio->stripes + index_where_to_add; 4841 struct btrfs_bio_stripe *old = 4842 bbio->stripes + i; 4843 4844 new->physical = old->physical; 4845 new->length = old->length; 4846 new->dev = dev_replace->tgtdev; 4847 index_where_to_add++; 4848 max_errors++; 4849 } 4850 } 4851 num_stripes = index_where_to_add; 4852 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) && 4853 dev_replace->tgtdev != NULL) { 4854 u64 srcdev_devid = dev_replace->srcdev->devid; 4855 int index_srcdev = 0; 4856 int found = 0; 4857 u64 physical_of_found = 0; 4858 4859 /* 4860 * During the dev-replace procedure, the target drive can 4861 * also be used to read data in case it is needed to repair 4862 * a corrupt block elsewhere. This is possible if the 4863 * requested area is left of the left cursor. In this area, 4864 * the target drive is a full copy of the source drive. 4865 */ 4866 for (i = 0; i < num_stripes; i++) { 4867 if (bbio->stripes[i].dev->devid == srcdev_devid) { 4868 /* 4869 * In case of DUP, in order to keep it 4870 * simple, only add the mirror with the 4871 * lowest physical address 4872 */ 4873 if (found && 4874 physical_of_found <= 4875 bbio->stripes[i].physical) 4876 continue; 4877 index_srcdev = i; 4878 found = 1; 4879 physical_of_found = bbio->stripes[i].physical; 4880 } 4881 } 4882 if (found) { 4883 u64 length = map->stripe_len; 4884 4885 if (physical_of_found + length <= 4886 dev_replace->cursor_left) { 4887 struct btrfs_bio_stripe *tgtdev_stripe = 4888 bbio->stripes + num_stripes; 4889 4890 tgtdev_stripe->physical = physical_of_found; 4891 tgtdev_stripe->length = 4892 bbio->stripes[index_srcdev].length; 4893 tgtdev_stripe->dev = dev_replace->tgtdev; 4894 4895 num_stripes++; 4896 } 4897 } 4898 } 4899 4900 *bbio_ret = bbio; 4901 bbio->num_stripes = num_stripes; 4902 bbio->max_errors = max_errors; 4903 bbio->mirror_num = mirror_num; 4904 4905 /* 4906 * this is the case that REQ_READ && dev_replace_is_ongoing && 4907 * mirror_num == num_stripes + 1 && dev_replace target drive is 4908 * available as a mirror 4909 */ 4910 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) { 4911 WARN_ON(num_stripes > 1); 4912 bbio->stripes[0].dev = dev_replace->tgtdev; 4913 bbio->stripes[0].physical = physical_to_patch_in_first_stripe; 4914 bbio->mirror_num = map->num_stripes + 1; 4915 } 4916 if (raid_map) { 4917 sort_parity_stripes(bbio, raid_map); 4918 *raid_map_ret = raid_map; 4919 } 4920 out: 4921 if (dev_replace_is_ongoing) 4922 btrfs_dev_replace_unlock(dev_replace); 4923 free_extent_map(em); 4924 return ret; 4925 } 4926 4927 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, 4928 u64 logical, u64 *length, 4929 struct btrfs_bio **bbio_ret, int mirror_num) 4930 { 4931 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret, 4932 mirror_num, NULL); 4933 } 4934 4935 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, 4936 u64 chunk_start, u64 physical, u64 devid, 4937 u64 **logical, int *naddrs, int *stripe_len) 4938 { 4939 struct extent_map_tree *em_tree = &map_tree->map_tree; 4940 struct extent_map *em; 4941 struct map_lookup *map; 4942 u64 *buf; 4943 u64 bytenr; 4944 u64 length; 4945 u64 stripe_nr; 4946 u64 rmap_len; 4947 int i, j, nr = 0; 4948 4949 read_lock(&em_tree->lock); 4950 em = lookup_extent_mapping(em_tree, chunk_start, 1); 4951 read_unlock(&em_tree->lock); 4952 4953 if (!em) { 4954 printk(KERN_ERR "btrfs: couldn't find em for chunk %Lu\n", 4955 chunk_start); 4956 return -EIO; 4957 } 4958 4959 if (em->start != chunk_start) { 4960 printk(KERN_ERR "btrfs: bad chunk start, em=%Lu, wanted=%Lu\n", 4961 em->start, chunk_start); 4962 free_extent_map(em); 4963 return -EIO; 4964 } 4965 map = (struct map_lookup *)em->bdev; 4966 4967 length = em->len; 4968 rmap_len = map->stripe_len; 4969 4970 if (map->type & BTRFS_BLOCK_GROUP_RAID10) 4971 do_div(length, map->num_stripes / map->sub_stripes); 4972 else if (map->type & BTRFS_BLOCK_GROUP_RAID0) 4973 do_div(length, map->num_stripes); 4974 else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | 4975 BTRFS_BLOCK_GROUP_RAID6)) { 4976 do_div(length, nr_data_stripes(map)); 4977 rmap_len = map->stripe_len * nr_data_stripes(map); 4978 } 4979 4980 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS); 4981 BUG_ON(!buf); /* -ENOMEM */ 4982 4983 for (i = 0; i < map->num_stripes; i++) { 4984 if (devid && map->stripes[i].dev->devid != devid) 4985 continue; 4986 if (map->stripes[i].physical > physical || 4987 map->stripes[i].physical + length <= physical) 4988 continue; 4989 4990 stripe_nr = physical - map->stripes[i].physical; 4991 do_div(stripe_nr, map->stripe_len); 4992 4993 if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 4994 stripe_nr = stripe_nr * map->num_stripes + i; 4995 do_div(stripe_nr, map->sub_stripes); 4996 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 4997 stripe_nr = stripe_nr * map->num_stripes + i; 4998 } /* else if RAID[56], multiply by nr_data_stripes(). 4999 * Alternatively, just use rmap_len below instead of 5000 * map->stripe_len */ 5001 5002 bytenr = chunk_start + stripe_nr * rmap_len; 5003 WARN_ON(nr >= map->num_stripes); 5004 for (j = 0; j < nr; j++) { 5005 if (buf[j] == bytenr) 5006 break; 5007 } 5008 if (j == nr) { 5009 WARN_ON(nr >= map->num_stripes); 5010 buf[nr++] = bytenr; 5011 } 5012 } 5013 5014 *logical = buf; 5015 *naddrs = nr; 5016 *stripe_len = rmap_len; 5017 5018 free_extent_map(em); 5019 return 0; 5020 } 5021 5022 static void *merge_stripe_index_into_bio_private(void *bi_private, 5023 unsigned int stripe_index) 5024 { 5025 /* 5026 * with single, dup, RAID0, RAID1 and RAID10, stripe_index is 5027 * at most 1. 5028 * The alternative solution (instead of stealing bits from the 5029 * pointer) would be to allocate an intermediate structure 5030 * that contains the old private pointer plus the stripe_index. 5031 */ 5032 BUG_ON((((uintptr_t)bi_private) & 3) != 0); 5033 BUG_ON(stripe_index > 3); 5034 return (void *)(((uintptr_t)bi_private) | stripe_index); 5035 } 5036 5037 static struct btrfs_bio *extract_bbio_from_bio_private(void *bi_private) 5038 { 5039 return (struct btrfs_bio *)(((uintptr_t)bi_private) & ~((uintptr_t)3)); 5040 } 5041 5042 static unsigned int extract_stripe_index_from_bio_private(void *bi_private) 5043 { 5044 return (unsigned int)((uintptr_t)bi_private) & 3; 5045 } 5046 5047 static void btrfs_end_bio(struct bio *bio, int err) 5048 { 5049 struct btrfs_bio *bbio = extract_bbio_from_bio_private(bio->bi_private); 5050 int is_orig_bio = 0; 5051 5052 if (err) { 5053 atomic_inc(&bbio->error); 5054 if (err == -EIO || err == -EREMOTEIO) { 5055 unsigned int stripe_index = 5056 extract_stripe_index_from_bio_private( 5057 bio->bi_private); 5058 struct btrfs_device *dev; 5059 5060 BUG_ON(stripe_index >= bbio->num_stripes); 5061 dev = bbio->stripes[stripe_index].dev; 5062 if (dev->bdev) { 5063 if (bio->bi_rw & WRITE) 5064 btrfs_dev_stat_inc(dev, 5065 BTRFS_DEV_STAT_WRITE_ERRS); 5066 else 5067 btrfs_dev_stat_inc(dev, 5068 BTRFS_DEV_STAT_READ_ERRS); 5069 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH) 5070 btrfs_dev_stat_inc(dev, 5071 BTRFS_DEV_STAT_FLUSH_ERRS); 5072 btrfs_dev_stat_print_on_error(dev); 5073 } 5074 } 5075 } 5076 5077 if (bio == bbio->orig_bio) 5078 is_orig_bio = 1; 5079 5080 if (atomic_dec_and_test(&bbio->stripes_pending)) { 5081 if (!is_orig_bio) { 5082 bio_put(bio); 5083 bio = bbio->orig_bio; 5084 } 5085 bio->bi_private = bbio->private; 5086 bio->bi_end_io = bbio->end_io; 5087 bio->bi_bdev = (struct block_device *) 5088 (unsigned long)bbio->mirror_num; 5089 /* only send an error to the higher layers if it is 5090 * beyond the tolerance of the btrfs bio 5091 */ 5092 if (atomic_read(&bbio->error) > bbio->max_errors) { 5093 err = -EIO; 5094 } else { 5095 /* 5096 * this bio is actually up to date, we didn't 5097 * go over the max number of errors 5098 */ 5099 set_bit(BIO_UPTODATE, &bio->bi_flags); 5100 err = 0; 5101 } 5102 kfree(bbio); 5103 5104 bio_endio(bio, err); 5105 } else if (!is_orig_bio) { 5106 bio_put(bio); 5107 } 5108 } 5109 5110 struct async_sched { 5111 struct bio *bio; 5112 int rw; 5113 struct btrfs_fs_info *info; 5114 struct btrfs_work work; 5115 }; 5116 5117 /* 5118 * see run_scheduled_bios for a description of why bios are collected for 5119 * async submit. 5120 * 5121 * This will add one bio to the pending list for a device and make sure 5122 * the work struct is scheduled. 5123 */ 5124 static noinline void btrfs_schedule_bio(struct btrfs_root *root, 5125 struct btrfs_device *device, 5126 int rw, struct bio *bio) 5127 { 5128 int should_queue = 1; 5129 struct btrfs_pending_bios *pending_bios; 5130 5131 if (device->missing || !device->bdev) { 5132 bio_endio(bio, -EIO); 5133 return; 5134 } 5135 5136 /* don't bother with additional async steps for reads, right now */ 5137 if (!(rw & REQ_WRITE)) { 5138 bio_get(bio); 5139 btrfsic_submit_bio(rw, bio); 5140 bio_put(bio); 5141 return; 5142 } 5143 5144 /* 5145 * nr_async_bios allows us to reliably return congestion to the 5146 * higher layers. Otherwise, the async bio makes it appear we have 5147 * made progress against dirty pages when we've really just put it 5148 * on a queue for later 5149 */ 5150 atomic_inc(&root->fs_info->nr_async_bios); 5151 WARN_ON(bio->bi_next); 5152 bio->bi_next = NULL; 5153 bio->bi_rw |= rw; 5154 5155 spin_lock(&device->io_lock); 5156 if (bio->bi_rw & REQ_SYNC) 5157 pending_bios = &device->pending_sync_bios; 5158 else 5159 pending_bios = &device->pending_bios; 5160 5161 if (pending_bios->tail) 5162 pending_bios->tail->bi_next = bio; 5163 5164 pending_bios->tail = bio; 5165 if (!pending_bios->head) 5166 pending_bios->head = bio; 5167 if (device->running_pending) 5168 should_queue = 0; 5169 5170 spin_unlock(&device->io_lock); 5171 5172 if (should_queue) 5173 btrfs_queue_worker(&root->fs_info->submit_workers, 5174 &device->work); 5175 } 5176 5177 static int bio_size_ok(struct block_device *bdev, struct bio *bio, 5178 sector_t sector) 5179 { 5180 struct bio_vec *prev; 5181 struct request_queue *q = bdev_get_queue(bdev); 5182 unsigned short max_sectors = queue_max_sectors(q); 5183 struct bvec_merge_data bvm = { 5184 .bi_bdev = bdev, 5185 .bi_sector = sector, 5186 .bi_rw = bio->bi_rw, 5187 }; 5188 5189 if (bio->bi_vcnt == 0) { 5190 WARN_ON(1); 5191 return 1; 5192 } 5193 5194 prev = &bio->bi_io_vec[bio->bi_vcnt - 1]; 5195 if (bio_sectors(bio) > max_sectors) 5196 return 0; 5197 5198 if (!q->merge_bvec_fn) 5199 return 1; 5200 5201 bvm.bi_size = bio->bi_size - prev->bv_len; 5202 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len) 5203 return 0; 5204 return 1; 5205 } 5206 5207 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 5208 struct bio *bio, u64 physical, int dev_nr, 5209 int rw, int async) 5210 { 5211 struct btrfs_device *dev = bbio->stripes[dev_nr].dev; 5212 5213 bio->bi_private = bbio; 5214 bio->bi_private = merge_stripe_index_into_bio_private( 5215 bio->bi_private, (unsigned int)dev_nr); 5216 bio->bi_end_io = btrfs_end_bio; 5217 bio->bi_sector = physical >> 9; 5218 #ifdef DEBUG 5219 { 5220 struct rcu_string *name; 5221 5222 rcu_read_lock(); 5223 name = rcu_dereference(dev->name); 5224 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu " 5225 "(%s id %llu), size=%u\n", rw, 5226 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, 5227 name->str, dev->devid, bio->bi_size); 5228 rcu_read_unlock(); 5229 } 5230 #endif 5231 bio->bi_bdev = dev->bdev; 5232 if (async) 5233 btrfs_schedule_bio(root, dev, rw, bio); 5234 else 5235 btrfsic_submit_bio(rw, bio); 5236 } 5237 5238 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio, 5239 struct bio *first_bio, struct btrfs_device *dev, 5240 int dev_nr, int rw, int async) 5241 { 5242 struct bio_vec *bvec = first_bio->bi_io_vec; 5243 struct bio *bio; 5244 int nr_vecs = bio_get_nr_vecs(dev->bdev); 5245 u64 physical = bbio->stripes[dev_nr].physical; 5246 5247 again: 5248 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS); 5249 if (!bio) 5250 return -ENOMEM; 5251 5252 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) { 5253 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len, 5254 bvec->bv_offset) < bvec->bv_len) { 5255 u64 len = bio->bi_size; 5256 5257 atomic_inc(&bbio->stripes_pending); 5258 submit_stripe_bio(root, bbio, bio, physical, dev_nr, 5259 rw, async); 5260 physical += len; 5261 goto again; 5262 } 5263 bvec++; 5264 } 5265 5266 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async); 5267 return 0; 5268 } 5269 5270 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical) 5271 { 5272 atomic_inc(&bbio->error); 5273 if (atomic_dec_and_test(&bbio->stripes_pending)) { 5274 bio->bi_private = bbio->private; 5275 bio->bi_end_io = bbio->end_io; 5276 bio->bi_bdev = (struct block_device *) 5277 (unsigned long)bbio->mirror_num; 5278 bio->bi_sector = logical >> 9; 5279 kfree(bbio); 5280 bio_endio(bio, -EIO); 5281 } 5282 } 5283 5284 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, 5285 int mirror_num, int async_submit) 5286 { 5287 struct btrfs_device *dev; 5288 struct bio *first_bio = bio; 5289 u64 logical = (u64)bio->bi_sector << 9; 5290 u64 length = 0; 5291 u64 map_length; 5292 u64 *raid_map = NULL; 5293 int ret; 5294 int dev_nr = 0; 5295 int total_devs = 1; 5296 struct btrfs_bio *bbio = NULL; 5297 5298 length = bio->bi_size; 5299 map_length = length; 5300 5301 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio, 5302 mirror_num, &raid_map); 5303 if (ret) /* -ENOMEM */ 5304 return ret; 5305 5306 total_devs = bbio->num_stripes; 5307 bbio->orig_bio = first_bio; 5308 bbio->private = first_bio->bi_private; 5309 bbio->end_io = first_bio->bi_end_io; 5310 atomic_set(&bbio->stripes_pending, bbio->num_stripes); 5311 5312 if (raid_map) { 5313 /* In this case, map_length has been set to the length of 5314 a single stripe; not the whole write */ 5315 if (rw & WRITE) { 5316 return raid56_parity_write(root, bio, bbio, 5317 raid_map, map_length); 5318 } else { 5319 return raid56_parity_recover(root, bio, bbio, 5320 raid_map, map_length, 5321 mirror_num); 5322 } 5323 } 5324 5325 if (map_length < length) { 5326 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu", 5327 (unsigned long long)logical, 5328 (unsigned long long)length, 5329 (unsigned long long)map_length); 5330 BUG(); 5331 } 5332 5333 while (dev_nr < total_devs) { 5334 dev = bbio->stripes[dev_nr].dev; 5335 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) { 5336 bbio_error(bbio, first_bio, logical); 5337 dev_nr++; 5338 continue; 5339 } 5340 5341 /* 5342 * Check and see if we're ok with this bio based on it's size 5343 * and offset with the given device. 5344 */ 5345 if (!bio_size_ok(dev->bdev, first_bio, 5346 bbio->stripes[dev_nr].physical >> 9)) { 5347 ret = breakup_stripe_bio(root, bbio, first_bio, dev, 5348 dev_nr, rw, async_submit); 5349 BUG_ON(ret); 5350 dev_nr++; 5351 continue; 5352 } 5353 5354 if (dev_nr < total_devs - 1) { 5355 bio = bio_clone(first_bio, GFP_NOFS); 5356 BUG_ON(!bio); /* -ENOMEM */ 5357 } else { 5358 bio = first_bio; 5359 } 5360 5361 submit_stripe_bio(root, bbio, bio, 5362 bbio->stripes[dev_nr].physical, dev_nr, rw, 5363 async_submit); 5364 dev_nr++; 5365 } 5366 return 0; 5367 } 5368 5369 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, 5370 u8 *uuid, u8 *fsid) 5371 { 5372 struct btrfs_device *device; 5373 struct btrfs_fs_devices *cur_devices; 5374 5375 cur_devices = fs_info->fs_devices; 5376 while (cur_devices) { 5377 if (!fsid || 5378 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5379 device = __find_device(&cur_devices->devices, 5380 devid, uuid); 5381 if (device) 5382 return device; 5383 } 5384 cur_devices = cur_devices->seed; 5385 } 5386 return NULL; 5387 } 5388 5389 static struct btrfs_device *add_missing_dev(struct btrfs_root *root, 5390 u64 devid, u8 *dev_uuid) 5391 { 5392 struct btrfs_device *device; 5393 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5394 5395 device = kzalloc(sizeof(*device), GFP_NOFS); 5396 if (!device) 5397 return NULL; 5398 list_add(&device->dev_list, 5399 &fs_devices->devices); 5400 device->dev_root = root->fs_info->dev_root; 5401 device->devid = devid; 5402 device->work.func = pending_bios_fn; 5403 device->fs_devices = fs_devices; 5404 device->missing = 1; 5405 fs_devices->num_devices++; 5406 fs_devices->missing_devices++; 5407 spin_lock_init(&device->io_lock); 5408 INIT_LIST_HEAD(&device->dev_alloc_list); 5409 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE); 5410 return device; 5411 } 5412 5413 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, 5414 struct extent_buffer *leaf, 5415 struct btrfs_chunk *chunk) 5416 { 5417 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; 5418 struct map_lookup *map; 5419 struct extent_map *em; 5420 u64 logical; 5421 u64 length; 5422 u64 devid; 5423 u8 uuid[BTRFS_UUID_SIZE]; 5424 int num_stripes; 5425 int ret; 5426 int i; 5427 5428 logical = key->offset; 5429 length = btrfs_chunk_length(leaf, chunk); 5430 5431 read_lock(&map_tree->map_tree.lock); 5432 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1); 5433 read_unlock(&map_tree->map_tree.lock); 5434 5435 /* already mapped? */ 5436 if (em && em->start <= logical && em->start + em->len > logical) { 5437 free_extent_map(em); 5438 return 0; 5439 } else if (em) { 5440 free_extent_map(em); 5441 } 5442 5443 em = alloc_extent_map(); 5444 if (!em) 5445 return -ENOMEM; 5446 num_stripes = btrfs_chunk_num_stripes(leaf, chunk); 5447 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); 5448 if (!map) { 5449 free_extent_map(em); 5450 return -ENOMEM; 5451 } 5452 5453 em->bdev = (struct block_device *)map; 5454 em->start = logical; 5455 em->len = length; 5456 em->orig_start = 0; 5457 em->block_start = 0; 5458 em->block_len = em->len; 5459 5460 map->num_stripes = num_stripes; 5461 map->io_width = btrfs_chunk_io_width(leaf, chunk); 5462 map->io_align = btrfs_chunk_io_align(leaf, chunk); 5463 map->sector_size = btrfs_chunk_sector_size(leaf, chunk); 5464 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk); 5465 map->type = btrfs_chunk_type(leaf, chunk); 5466 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); 5467 for (i = 0; i < num_stripes; i++) { 5468 map->stripes[i].physical = 5469 btrfs_stripe_offset_nr(leaf, chunk, i); 5470 devid = btrfs_stripe_devid_nr(leaf, chunk, i); 5471 read_extent_buffer(leaf, uuid, (unsigned long) 5472 btrfs_stripe_dev_uuid_nr(chunk, i), 5473 BTRFS_UUID_SIZE); 5474 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid, 5475 uuid, NULL); 5476 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) { 5477 kfree(map); 5478 free_extent_map(em); 5479 return -EIO; 5480 } 5481 if (!map->stripes[i].dev) { 5482 map->stripes[i].dev = 5483 add_missing_dev(root, devid, uuid); 5484 if (!map->stripes[i].dev) { 5485 kfree(map); 5486 free_extent_map(em); 5487 return -EIO; 5488 } 5489 } 5490 map->stripes[i].dev->in_fs_metadata = 1; 5491 } 5492 5493 write_lock(&map_tree->map_tree.lock); 5494 ret = add_extent_mapping(&map_tree->map_tree, em, 0); 5495 write_unlock(&map_tree->map_tree.lock); 5496 BUG_ON(ret); /* Tree corruption */ 5497 free_extent_map(em); 5498 5499 return 0; 5500 } 5501 5502 static void fill_device_from_item(struct extent_buffer *leaf, 5503 struct btrfs_dev_item *dev_item, 5504 struct btrfs_device *device) 5505 { 5506 unsigned long ptr; 5507 5508 device->devid = btrfs_device_id(leaf, dev_item); 5509 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item); 5510 device->total_bytes = device->disk_total_bytes; 5511 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item); 5512 device->type = btrfs_device_type(leaf, dev_item); 5513 device->io_align = btrfs_device_io_align(leaf, dev_item); 5514 device->io_width = btrfs_device_io_width(leaf, dev_item); 5515 device->sector_size = btrfs_device_sector_size(leaf, dev_item); 5516 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); 5517 device->is_tgtdev_for_dev_replace = 0; 5518 5519 ptr = (unsigned long)btrfs_device_uuid(dev_item); 5520 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); 5521 } 5522 5523 static int open_seed_devices(struct btrfs_root *root, u8 *fsid) 5524 { 5525 struct btrfs_fs_devices *fs_devices; 5526 int ret; 5527 5528 BUG_ON(!mutex_is_locked(&uuid_mutex)); 5529 5530 fs_devices = root->fs_info->fs_devices->seed; 5531 while (fs_devices) { 5532 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) { 5533 ret = 0; 5534 goto out; 5535 } 5536 fs_devices = fs_devices->seed; 5537 } 5538 5539 fs_devices = find_fsid(fsid); 5540 if (!fs_devices) { 5541 ret = -ENOENT; 5542 goto out; 5543 } 5544 5545 fs_devices = clone_fs_devices(fs_devices); 5546 if (IS_ERR(fs_devices)) { 5547 ret = PTR_ERR(fs_devices); 5548 goto out; 5549 } 5550 5551 ret = __btrfs_open_devices(fs_devices, FMODE_READ, 5552 root->fs_info->bdev_holder); 5553 if (ret) { 5554 free_fs_devices(fs_devices); 5555 goto out; 5556 } 5557 5558 if (!fs_devices->seeding) { 5559 __btrfs_close_devices(fs_devices); 5560 free_fs_devices(fs_devices); 5561 ret = -EINVAL; 5562 goto out; 5563 } 5564 5565 fs_devices->seed = root->fs_info->fs_devices->seed; 5566 root->fs_info->fs_devices->seed = fs_devices; 5567 out: 5568 return ret; 5569 } 5570 5571 static int read_one_dev(struct btrfs_root *root, 5572 struct extent_buffer *leaf, 5573 struct btrfs_dev_item *dev_item) 5574 { 5575 struct btrfs_device *device; 5576 u64 devid; 5577 int ret; 5578 u8 fs_uuid[BTRFS_UUID_SIZE]; 5579 u8 dev_uuid[BTRFS_UUID_SIZE]; 5580 5581 devid = btrfs_device_id(leaf, dev_item); 5582 read_extent_buffer(leaf, dev_uuid, 5583 (unsigned long)btrfs_device_uuid(dev_item), 5584 BTRFS_UUID_SIZE); 5585 read_extent_buffer(leaf, fs_uuid, 5586 (unsigned long)btrfs_device_fsid(dev_item), 5587 BTRFS_UUID_SIZE); 5588 5589 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) { 5590 ret = open_seed_devices(root, fs_uuid); 5591 if (ret && !btrfs_test_opt(root, DEGRADED)) 5592 return ret; 5593 } 5594 5595 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid); 5596 if (!device || !device->bdev) { 5597 if (!btrfs_test_opt(root, DEGRADED)) 5598 return -EIO; 5599 5600 if (!device) { 5601 btrfs_warn(root->fs_info, "devid %llu missing", 5602 (unsigned long long)devid); 5603 device = add_missing_dev(root, devid, dev_uuid); 5604 if (!device) 5605 return -ENOMEM; 5606 } else if (!device->missing) { 5607 /* 5608 * this happens when a device that was properly setup 5609 * in the device info lists suddenly goes bad. 5610 * device->bdev is NULL, and so we have to set 5611 * device->missing to one here 5612 */ 5613 root->fs_info->fs_devices->missing_devices++; 5614 device->missing = 1; 5615 } 5616 } 5617 5618 if (device->fs_devices != root->fs_info->fs_devices) { 5619 BUG_ON(device->writeable); 5620 if (device->generation != 5621 btrfs_device_generation(leaf, dev_item)) 5622 return -EINVAL; 5623 } 5624 5625 fill_device_from_item(leaf, dev_item, device); 5626 device->dev_root = root->fs_info->dev_root; 5627 device->in_fs_metadata = 1; 5628 if (device->writeable && !device->is_tgtdev_for_dev_replace) { 5629 device->fs_devices->total_rw_bytes += device->total_bytes; 5630 spin_lock(&root->fs_info->free_chunk_lock); 5631 root->fs_info->free_chunk_space += device->total_bytes - 5632 device->bytes_used; 5633 spin_unlock(&root->fs_info->free_chunk_lock); 5634 } 5635 ret = 0; 5636 return ret; 5637 } 5638 5639 int btrfs_read_sys_array(struct btrfs_root *root) 5640 { 5641 struct btrfs_super_block *super_copy = root->fs_info->super_copy; 5642 struct extent_buffer *sb; 5643 struct btrfs_disk_key *disk_key; 5644 struct btrfs_chunk *chunk; 5645 u8 *ptr; 5646 unsigned long sb_ptr; 5647 int ret = 0; 5648 u32 num_stripes; 5649 u32 array_size; 5650 u32 len = 0; 5651 u32 cur; 5652 struct btrfs_key key; 5653 5654 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET, 5655 BTRFS_SUPER_INFO_SIZE); 5656 if (!sb) 5657 return -ENOMEM; 5658 btrfs_set_buffer_uptodate(sb); 5659 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); 5660 /* 5661 * The sb extent buffer is artifical and just used to read the system array. 5662 * btrfs_set_buffer_uptodate() call does not properly mark all it's 5663 * pages up-to-date when the page is larger: extent does not cover the 5664 * whole page and consequently check_page_uptodate does not find all 5665 * the page's extents up-to-date (the hole beyond sb), 5666 * write_extent_buffer then triggers a WARN_ON. 5667 * 5668 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle, 5669 * but sb spans only this function. Add an explicit SetPageUptodate call 5670 * to silence the warning eg. on PowerPC 64. 5671 */ 5672 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE) 5673 SetPageUptodate(sb->pages[0]); 5674 5675 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); 5676 array_size = btrfs_super_sys_array_size(super_copy); 5677 5678 ptr = super_copy->sys_chunk_array; 5679 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array); 5680 cur = 0; 5681 5682 while (cur < array_size) { 5683 disk_key = (struct btrfs_disk_key *)ptr; 5684 btrfs_disk_key_to_cpu(&key, disk_key); 5685 5686 len = sizeof(*disk_key); ptr += len; 5687 sb_ptr += len; 5688 cur += len; 5689 5690 if (key.type == BTRFS_CHUNK_ITEM_KEY) { 5691 chunk = (struct btrfs_chunk *)sb_ptr; 5692 ret = read_one_chunk(root, &key, sb, chunk); 5693 if (ret) 5694 break; 5695 num_stripes = btrfs_chunk_num_stripes(sb, chunk); 5696 len = btrfs_chunk_item_size(num_stripes); 5697 } else { 5698 ret = -EIO; 5699 break; 5700 } 5701 ptr += len; 5702 sb_ptr += len; 5703 cur += len; 5704 } 5705 free_extent_buffer(sb); 5706 return ret; 5707 } 5708 5709 int btrfs_read_chunk_tree(struct btrfs_root *root) 5710 { 5711 struct btrfs_path *path; 5712 struct extent_buffer *leaf; 5713 struct btrfs_key key; 5714 struct btrfs_key found_key; 5715 int ret; 5716 int slot; 5717 5718 root = root->fs_info->chunk_root; 5719 5720 path = btrfs_alloc_path(); 5721 if (!path) 5722 return -ENOMEM; 5723 5724 mutex_lock(&uuid_mutex); 5725 lock_chunks(root); 5726 5727 /* first we search for all of the device items, and then we 5728 * read in all of the chunk items. This way we can create chunk 5729 * mappings that reference all of the devices that are afound 5730 */ 5731 key.objectid = BTRFS_DEV_ITEMS_OBJECTID; 5732 key.offset = 0; 5733 key.type = 0; 5734 again: 5735 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 5736 if (ret < 0) 5737 goto error; 5738 while (1) { 5739 leaf = path->nodes[0]; 5740 slot = path->slots[0]; 5741 if (slot >= btrfs_header_nritems(leaf)) { 5742 ret = btrfs_next_leaf(root, path); 5743 if (ret == 0) 5744 continue; 5745 if (ret < 0) 5746 goto error; 5747 break; 5748 } 5749 btrfs_item_key_to_cpu(leaf, &found_key, slot); 5750 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5751 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID) 5752 break; 5753 if (found_key.type == BTRFS_DEV_ITEM_KEY) { 5754 struct btrfs_dev_item *dev_item; 5755 dev_item = btrfs_item_ptr(leaf, slot, 5756 struct btrfs_dev_item); 5757 ret = read_one_dev(root, leaf, dev_item); 5758 if (ret) 5759 goto error; 5760 } 5761 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) { 5762 struct btrfs_chunk *chunk; 5763 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk); 5764 ret = read_one_chunk(root, &found_key, leaf, chunk); 5765 if (ret) 5766 goto error; 5767 } 5768 path->slots[0]++; 5769 } 5770 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) { 5771 key.objectid = 0; 5772 btrfs_release_path(path); 5773 goto again; 5774 } 5775 ret = 0; 5776 error: 5777 unlock_chunks(root); 5778 mutex_unlock(&uuid_mutex); 5779 5780 btrfs_free_path(path); 5781 return ret; 5782 } 5783 5784 static void __btrfs_reset_dev_stats(struct btrfs_device *dev) 5785 { 5786 int i; 5787 5788 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5789 btrfs_dev_stat_reset(dev, i); 5790 } 5791 5792 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) 5793 { 5794 struct btrfs_key key; 5795 struct btrfs_key found_key; 5796 struct btrfs_root *dev_root = fs_info->dev_root; 5797 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5798 struct extent_buffer *eb; 5799 int slot; 5800 int ret = 0; 5801 struct btrfs_device *device; 5802 struct btrfs_path *path = NULL; 5803 int i; 5804 5805 path = btrfs_alloc_path(); 5806 if (!path) { 5807 ret = -ENOMEM; 5808 goto out; 5809 } 5810 5811 mutex_lock(&fs_devices->device_list_mutex); 5812 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5813 int item_size; 5814 struct btrfs_dev_stats_item *ptr; 5815 5816 key.objectid = 0; 5817 key.type = BTRFS_DEV_STATS_KEY; 5818 key.offset = device->devid; 5819 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); 5820 if (ret) { 5821 __btrfs_reset_dev_stats(device); 5822 device->dev_stats_valid = 1; 5823 btrfs_release_path(path); 5824 continue; 5825 } 5826 slot = path->slots[0]; 5827 eb = path->nodes[0]; 5828 btrfs_item_key_to_cpu(eb, &found_key, slot); 5829 item_size = btrfs_item_size_nr(eb, slot); 5830 5831 ptr = btrfs_item_ptr(eb, slot, 5832 struct btrfs_dev_stats_item); 5833 5834 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 5835 if (item_size >= (1 + i) * sizeof(__le64)) 5836 btrfs_dev_stat_set(device, i, 5837 btrfs_dev_stats_value(eb, ptr, i)); 5838 else 5839 btrfs_dev_stat_reset(device, i); 5840 } 5841 5842 device->dev_stats_valid = 1; 5843 btrfs_dev_stat_print_on_load(device); 5844 btrfs_release_path(path); 5845 } 5846 mutex_unlock(&fs_devices->device_list_mutex); 5847 5848 out: 5849 btrfs_free_path(path); 5850 return ret < 0 ? ret : 0; 5851 } 5852 5853 static int update_dev_stat_item(struct btrfs_trans_handle *trans, 5854 struct btrfs_root *dev_root, 5855 struct btrfs_device *device) 5856 { 5857 struct btrfs_path *path; 5858 struct btrfs_key key; 5859 struct extent_buffer *eb; 5860 struct btrfs_dev_stats_item *ptr; 5861 int ret; 5862 int i; 5863 5864 key.objectid = 0; 5865 key.type = BTRFS_DEV_STATS_KEY; 5866 key.offset = device->devid; 5867 5868 path = btrfs_alloc_path(); 5869 BUG_ON(!path); 5870 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); 5871 if (ret < 0) { 5872 printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n", 5873 ret, rcu_str_deref(device->name)); 5874 goto out; 5875 } 5876 5877 if (ret == 0 && 5878 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { 5879 /* need to delete old one and insert a new one */ 5880 ret = btrfs_del_item(trans, dev_root, path); 5881 if (ret != 0) { 5882 printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n", 5883 rcu_str_deref(device->name), ret); 5884 goto out; 5885 } 5886 ret = 1; 5887 } 5888 5889 if (ret == 1) { 5890 /* need to insert a new item */ 5891 btrfs_release_path(path); 5892 ret = btrfs_insert_empty_item(trans, dev_root, path, 5893 &key, sizeof(*ptr)); 5894 if (ret < 0) { 5895 printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n", 5896 rcu_str_deref(device->name), ret); 5897 goto out; 5898 } 5899 } 5900 5901 eb = path->nodes[0]; 5902 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); 5903 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5904 btrfs_set_dev_stats_value(eb, ptr, i, 5905 btrfs_dev_stat_read(device, i)); 5906 btrfs_mark_buffer_dirty(eb); 5907 5908 out: 5909 btrfs_free_path(path); 5910 return ret; 5911 } 5912 5913 /* 5914 * called from commit_transaction. Writes all changed device stats to disk. 5915 */ 5916 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, 5917 struct btrfs_fs_info *fs_info) 5918 { 5919 struct btrfs_root *dev_root = fs_info->dev_root; 5920 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; 5921 struct btrfs_device *device; 5922 int ret = 0; 5923 5924 mutex_lock(&fs_devices->device_list_mutex); 5925 list_for_each_entry(device, &fs_devices->devices, dev_list) { 5926 if (!device->dev_stats_valid || !device->dev_stats_dirty) 5927 continue; 5928 5929 ret = update_dev_stat_item(trans, dev_root, device); 5930 if (!ret) 5931 device->dev_stats_dirty = 0; 5932 } 5933 mutex_unlock(&fs_devices->device_list_mutex); 5934 5935 return ret; 5936 } 5937 5938 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) 5939 { 5940 btrfs_dev_stat_inc(dev, index); 5941 btrfs_dev_stat_print_on_error(dev); 5942 } 5943 5944 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev) 5945 { 5946 if (!dev->dev_stats_valid) 5947 return; 5948 printk_ratelimited_in_rcu(KERN_ERR 5949 "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5950 rcu_str_deref(dev->name), 5951 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5952 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5953 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5954 btrfs_dev_stat_read(dev, 5955 BTRFS_DEV_STAT_CORRUPTION_ERRS), 5956 btrfs_dev_stat_read(dev, 5957 BTRFS_DEV_STAT_GENERATION_ERRS)); 5958 } 5959 5960 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) 5961 { 5962 int i; 5963 5964 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 5965 if (btrfs_dev_stat_read(dev, i) != 0) 5966 break; 5967 if (i == BTRFS_DEV_STAT_VALUES_MAX) 5968 return; /* all values == 0, suppress message */ 5969 5970 printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", 5971 rcu_str_deref(dev->name), 5972 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), 5973 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), 5974 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), 5975 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), 5976 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); 5977 } 5978 5979 int btrfs_get_dev_stats(struct btrfs_root *root, 5980 struct btrfs_ioctl_get_dev_stats *stats) 5981 { 5982 struct btrfs_device *dev; 5983 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; 5984 int i; 5985 5986 mutex_lock(&fs_devices->device_list_mutex); 5987 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL); 5988 mutex_unlock(&fs_devices->device_list_mutex); 5989 5990 if (!dev) { 5991 printk(KERN_WARNING 5992 "btrfs: get dev_stats failed, device not found\n"); 5993 return -ENODEV; 5994 } else if (!dev->dev_stats_valid) { 5995 printk(KERN_WARNING 5996 "btrfs: get dev_stats failed, not yet valid\n"); 5997 return -ENODEV; 5998 } else if (stats->flags & BTRFS_DEV_STATS_RESET) { 5999 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { 6000 if (stats->nr_items > i) 6001 stats->values[i] = 6002 btrfs_dev_stat_read_and_reset(dev, i); 6003 else 6004 btrfs_dev_stat_reset(dev, i); 6005 } 6006 } else { 6007 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) 6008 if (stats->nr_items > i) 6009 stats->values[i] = btrfs_dev_stat_read(dev, i); 6010 } 6011 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) 6012 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; 6013 return 0; 6014 } 6015 6016 int btrfs_scratch_superblock(struct btrfs_device *device) 6017 { 6018 struct buffer_head *bh; 6019 struct btrfs_super_block *disk_super; 6020 6021 bh = btrfs_read_dev_super(device->bdev); 6022 if (!bh) 6023 return -EINVAL; 6024 disk_super = (struct btrfs_super_block *)bh->b_data; 6025 6026 memset(&disk_super->magic, 0, sizeof(disk_super->magic)); 6027 set_buffer_dirty(bh); 6028 sync_dirty_buffer(bh); 6029 brelse(bh); 6030 6031 return 0; 6032 } 6033