projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Merge tag 'iwlwifi-for-kalle-2015-04-28' of https://git.kernel.org/pub/scm/linux...
[deliverable/linux.git] / fs / btrfs / volumes.c
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 <linux/semaphore.h>
30 #include <asm/div64.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 #include "sysfs.h"
44
45 static int init_first_rw_device(struct btrfs_trans_handle *trans,
46 struct btrfs_root *root,
47 struct btrfs_device *device);
48 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
49 static void __btrfs_reset_dev_stats(struct btrfs_device *dev);
50 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev);
51 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
52
53 DEFINE_MUTEX(uuid_mutex);
54 static LIST_HEAD(fs_uuids);
55
56 static struct btrfs_fs_devices *__alloc_fs_devices(void)
57 {
58 struct btrfs_fs_devices *fs_devs;
59
60 fs_devs = kzalloc(sizeof(*fs_devs), GFP_NOFS);
61 if (!fs_devs)
62 return ERR_PTR(-ENOMEM);
63
64 mutex_init(&fs_devs->device_list_mutex);
65
66 INIT_LIST_HEAD(&fs_devs->devices);
67 INIT_LIST_HEAD(&fs_devs->resized_devices);
68 INIT_LIST_HEAD(&fs_devs->alloc_list);
69 INIT_LIST_HEAD(&fs_devs->list);
70
71 return fs_devs;
72 }
73
74 /**
75 * alloc_fs_devices - allocate struct btrfs_fs_devices
76 * @fsid: a pointer to UUID for this FS. If NULL a new UUID is
77 * generated.
78 *
79 * Return: a pointer to a new &struct btrfs_fs_devices on success;
80 * ERR_PTR() on error. Returned struct is not linked onto any lists and
81 * can be destroyed with kfree() right away.
82 */
83 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
84 {
85 struct btrfs_fs_devices *fs_devs;
86
87 fs_devs = __alloc_fs_devices();
88 if (IS_ERR(fs_devs))
89 return fs_devs;
90
91 if (fsid)
92 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
93 else
94 generate_random_uuid(fs_devs->fsid);
95
96 return fs_devs;
97 }
98
99 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
100 {
101 struct btrfs_device *device;
102 WARN_ON(fs_devices->opened);
103 while (!list_empty(&fs_devices->devices)) {
104 device = list_entry(fs_devices->devices.next,
105 struct btrfs_device, dev_list);
106 list_del(&device->dev_list);
107 rcu_string_free(device->name);
108 kfree(device);
109 }
110 kfree(fs_devices);
111 }
112
113 static void btrfs_kobject_uevent(struct block_device *bdev,
114 enum kobject_action action)
115 {
116 int ret;
117
118 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
119 if (ret)
120 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
121 action,
122 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
123 &disk_to_dev(bdev->bd_disk)->kobj);
124 }
125
126 void btrfs_cleanup_fs_uuids(void)
127 {
128 struct btrfs_fs_devices *fs_devices;
129
130 while (!list_empty(&fs_uuids)) {
131 fs_devices = list_entry(fs_uuids.next,
132 struct btrfs_fs_devices, list);
133 list_del(&fs_devices->list);
134 free_fs_devices(fs_devices);
135 }
136 }
137
138 static struct btrfs_device *__alloc_device(void)
139 {
140 struct btrfs_device *dev;
141
142 dev = kzalloc(sizeof(*dev), GFP_NOFS);
143 if (!dev)
144 return ERR_PTR(-ENOMEM);
145
146 INIT_LIST_HEAD(&dev->dev_list);
147 INIT_LIST_HEAD(&dev->dev_alloc_list);
148 INIT_LIST_HEAD(&dev->resized_list);
149
150 spin_lock_init(&dev->io_lock);
151
152 spin_lock_init(&dev->reada_lock);
153 atomic_set(&dev->reada_in_flight, 0);
154 atomic_set(&dev->dev_stats_ccnt, 0);
155 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_WAIT);
156 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_WAIT);
157
158 return dev;
159 }
160
161 static noinline struct btrfs_device *__find_device(struct list_head *head,
162 u64 devid, u8 *uuid)
163 {
164 struct btrfs_device *dev;
165
166 list_for_each_entry(dev, head, dev_list) {
167 if (dev->devid == devid &&
168 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
169 return dev;
170 }
171 }
172 return NULL;
173 }
174
175 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
176 {
177 struct btrfs_fs_devices *fs_devices;
178
179 list_for_each_entry(fs_devices, &fs_uuids, list) {
180 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
181 return fs_devices;
182 }
183 return NULL;
184 }
185
186 static int
187 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
188 int flush, struct block_device **bdev,
189 struct buffer_head **bh)
190 {
191 int ret;
192
193 *bdev = blkdev_get_by_path(device_path, flags, holder);
194
195 if (IS_ERR(*bdev)) {
196 ret = PTR_ERR(*bdev);
197 printk(KERN_INFO "BTRFS: open %s failed\n", device_path);
198 goto error;
199 }
200
201 if (flush)
202 filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
203 ret = set_blocksize(*bdev, 4096);
204 if (ret) {
205 blkdev_put(*bdev, flags);
206 goto error;
207 }
208 invalidate_bdev(*bdev);
209 *bh = btrfs_read_dev_super(*bdev);
210 if (!*bh) {
211 ret = -EINVAL;
212 blkdev_put(*bdev, flags);
213 goto error;
214 }
215
216 return 0;
217
218 error:
219 *bdev = NULL;
220 *bh = NULL;
221 return ret;
222 }
223
224 static void requeue_list(struct btrfs_pending_bios *pending_bios,
225 struct bio *head, struct bio *tail)
226 {
227
228 struct bio *old_head;
229
230 old_head = pending_bios->head;
231 pending_bios->head = head;
232 if (pending_bios->tail)
233 tail->bi_next = old_head;
234 else
235 pending_bios->tail = tail;
236 }
237
238 /*
239 * we try to collect pending bios for a device so we don't get a large
240 * number of procs sending bios down to the same device. This greatly
241 * improves the schedulers ability to collect and merge the bios.
242 *
243 * But, it also turns into a long list of bios to process and that is sure
244 * to eventually make the worker thread block. The solution here is to
245 * make some progress and then put this work struct back at the end of
246 * the list if the block device is congested. This way, multiple devices
247 * can make progress from a single worker thread.
248 */
249 static noinline void run_scheduled_bios(struct btrfs_device *device)
250 {
251 struct bio *pending;
252 struct backing_dev_info *bdi;
253 struct btrfs_fs_info *fs_info;
254 struct btrfs_pending_bios *pending_bios;
255 struct bio *tail;
256 struct bio *cur;
257 int again = 0;
258 unsigned long num_run;
259 unsigned long batch_run = 0;
260 unsigned long limit;
261 unsigned long last_waited = 0;
262 int force_reg = 0;
263 int sync_pending = 0;
264 struct blk_plug plug;
265
266 /*
267 * this function runs all the bios we've collected for
268 * a particular device. We don't want to wander off to
269 * another device without first sending all of these down.
270 * So, setup a plug here and finish it off before we return
271 */
272 blk_start_plug(&plug);
273
274 bdi = blk_get_backing_dev_info(device->bdev);
275 fs_info = device->dev_root->fs_info;
276 limit = btrfs_async_submit_limit(fs_info);
277 limit = limit * 2 / 3;
278
279 loop:
280 spin_lock(&device->io_lock);
281
282 loop_lock:
283 num_run = 0;
284
285 /* take all the bios off the list at once and process them
286 * later on (without the lock held). But, remember the
287 * tail and other pointers so the bios can be properly reinserted
288 * into the list if we hit congestion
289 */
290 if (!force_reg && device->pending_sync_bios.head) {
291 pending_bios = &device->pending_sync_bios;
292 force_reg = 1;
293 } else {
294 pending_bios = &device->pending_bios;
295 force_reg = 0;
296 }
297
298 pending = pending_bios->head;
299 tail = pending_bios->tail;
300 WARN_ON(pending && !tail);
301
302 /*
303 * if pending was null this time around, no bios need processing
304 * at all and we can stop. Otherwise it'll loop back up again
305 * and do an additional check so no bios are missed.
306 *
307 * device->running_pending is used to synchronize with the
308 * schedule_bio code.
309 */
310 if (device->pending_sync_bios.head == NULL &&
311 device->pending_bios.head == NULL) {
312 again = 0;
313 device->running_pending = 0;
314 } else {
315 again = 1;
316 device->running_pending = 1;
317 }
318
319 pending_bios->head = NULL;
320 pending_bios->tail = NULL;
321
322 spin_unlock(&device->io_lock);
323
324 while (pending) {
325
326 rmb();
327 /* we want to work on both lists, but do more bios on the
328 * sync list than the regular list
329 */
330 if ((num_run > 32 &&
331 pending_bios != &device->pending_sync_bios &&
332 device->pending_sync_bios.head) ||
333 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
334 device->pending_bios.head)) {
335 spin_lock(&device->io_lock);
336 requeue_list(pending_bios, pending, tail);
337 goto loop_lock;
338 }
339
340 cur = pending;
341 pending = pending->bi_next;
342 cur->bi_next = NULL;
343
344 if (atomic_dec_return(&fs_info->nr_async_bios) < limit &&
345 waitqueue_active(&fs_info->async_submit_wait))
346 wake_up(&fs_info->async_submit_wait);
347
348 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
349
350 /*
351 * if we're doing the sync list, record that our
352 * plug has some sync requests on it
353 *
354 * If we're doing the regular list and there are
355 * sync requests sitting around, unplug before
356 * we add more
357 */
358 if (pending_bios == &device->pending_sync_bios) {
359 sync_pending = 1;
360 } else if (sync_pending) {
361 blk_finish_plug(&plug);
362 blk_start_plug(&plug);
363 sync_pending = 0;
364 }
365
366 btrfsic_submit_bio(cur->bi_rw, cur);
367 num_run++;
368 batch_run++;
369
370 cond_resched();
371
372 /*
373 * we made progress, there is more work to do and the bdi
374 * is now congested. Back off and let other work structs
375 * run instead
376 */
377 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
378 fs_info->fs_devices->open_devices > 1) {
379 struct io_context *ioc;
380
381 ioc = current->io_context;
382
383 /*
384 * the main goal here is that we don't want to
385 * block if we're going to be able to submit
386 * more requests without blocking.
387 *
388 * This code does two great things, it pokes into
389 * the elevator code from a filesystem _and_
390 * it makes assumptions about how batching works.
391 */
392 if (ioc && ioc->nr_batch_requests > 0 &&
393 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
394 (last_waited == 0 ||
395 ioc->last_waited == last_waited)) {
396 /*
397 * we want to go through our batch of
398 * requests and stop. So, we copy out
399 * the ioc->last_waited time and test
400 * against it before looping
401 */
402 last_waited = ioc->last_waited;
403 cond_resched();
404 continue;
405 }
406 spin_lock(&device->io_lock);
407 requeue_list(pending_bios, pending, tail);
408 device->running_pending = 1;
409
410 spin_unlock(&device->io_lock);
411 btrfs_queue_work(fs_info->submit_workers,
412 &device->work);
413 goto done;
414 }
415 /* unplug every 64 requests just for good measure */
416 if (batch_run % 64 == 0) {
417 blk_finish_plug(&plug);
418 blk_start_plug(&plug);
419 sync_pending = 0;
420 }
421 }
422
423 cond_resched();
424 if (again)
425 goto loop;
426
427 spin_lock(&device->io_lock);
428 if (device->pending_bios.head || device->pending_sync_bios.head)
429 goto loop_lock;
430 spin_unlock(&device->io_lock);
431
432 done:
433 blk_finish_plug(&plug);
434 }
435
436 static void pending_bios_fn(struct btrfs_work *work)
437 {
438 struct btrfs_device *device;
439
440 device = container_of(work, struct btrfs_device, work);
441 run_scheduled_bios(device);
442 }
443
444 /*
445 * Add new device to list of registered devices
446 *
447 * Returns:
448 * 1 - first time device is seen
449 * 0 - device already known
450 * < 0 - error
451 */
452 static noinline int device_list_add(const char *path,
453 struct btrfs_super_block *disk_super,
454 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
455 {
456 struct btrfs_device *device;
457 struct btrfs_fs_devices *fs_devices;
458 struct rcu_string *name;
459 int ret = 0;
460 u64 found_transid = btrfs_super_generation(disk_super);
461
462 fs_devices = find_fsid(disk_super->fsid);
463 if (!fs_devices) {
464 fs_devices = alloc_fs_devices(disk_super->fsid);
465 if (IS_ERR(fs_devices))
466 return PTR_ERR(fs_devices);
467
468 list_add(&fs_devices->list, &fs_uuids);
469
470 device = NULL;
471 } else {
472 device = __find_device(&fs_devices->devices, devid,
473 disk_super->dev_item.uuid);
474 }
475
476 if (!device) {
477 if (fs_devices->opened)
478 return -EBUSY;
479
480 device = btrfs_alloc_device(NULL, &devid,
481 disk_super->dev_item.uuid);
482 if (IS_ERR(device)) {
483 /* we can safely leave the fs_devices entry around */
484 return PTR_ERR(device);
485 }
486
487 name = rcu_string_strdup(path, GFP_NOFS);
488 if (!name) {
489 kfree(device);
490 return -ENOMEM;
491 }
492 rcu_assign_pointer(device->name, name);
493
494 mutex_lock(&fs_devices->device_list_mutex);
495 list_add_rcu(&device->dev_list, &fs_devices->devices);
496 fs_devices->num_devices++;
497 mutex_unlock(&fs_devices->device_list_mutex);
498
499 ret = 1;
500 device->fs_devices = fs_devices;
501 } else if (!device->name || strcmp(device->name->str, path)) {
502 /*
503 * When FS is already mounted.
504 * 1. If you are here and if the device->name is NULL that
505 * means this device was missing at time of FS mount.
506 * 2. If you are here and if the device->name is different
507 * from 'path' that means either
508 * a. The same device disappeared and reappeared with
509 * different name. or
510 * b. The missing-disk-which-was-replaced, has
511 * reappeared now.
512 *
513 * We must allow 1 and 2a above. But 2b would be a spurious
514 * and unintentional.
515 *
516 * Further in case of 1 and 2a above, the disk at 'path'
517 * would have missed some transaction when it was away and
518 * in case of 2a the stale bdev has to be updated as well.
519 * 2b must not be allowed at all time.
520 */
521
522 /*
523 * For now, we do allow update to btrfs_fs_device through the
524 * btrfs dev scan cli after FS has been mounted. We're still
525 * tracking a problem where systems fail mount by subvolume id
526 * when we reject replacement on a mounted FS.
527 */
528 if (!fs_devices->opened && found_transid < device->generation) {
529 /*
530 * That is if the FS is _not_ mounted and if you
531 * are here, that means there is more than one
532 * disk with same uuid and devid.We keep the one
533 * with larger generation number or the last-in if
534 * generation are equal.
535 */
536 return -EEXIST;
537 }
538
539 name = rcu_string_strdup(path, GFP_NOFS);
540 if (!name)
541 return -ENOMEM;
542 rcu_string_free(device->name);
543 rcu_assign_pointer(device->name, name);
544 if (device->missing) {
545 fs_devices->missing_devices--;
546 device->missing = 0;
547 }
548 }
549
550 /*
551 * Unmount does not free the btrfs_device struct but would zero
552 * generation along with most of the other members. So just update
553 * it back. We need it to pick the disk with largest generation
554 * (as above).
555 */
556 if (!fs_devices->opened)
557 device->generation = found_transid;
558
559 *fs_devices_ret = fs_devices;
560
561 return ret;
562 }
563
564 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
565 {
566 struct btrfs_fs_devices *fs_devices;
567 struct btrfs_device *device;
568 struct btrfs_device *orig_dev;
569
570 fs_devices = alloc_fs_devices(orig->fsid);
571 if (IS_ERR(fs_devices))
572 return fs_devices;
573
574 mutex_lock(&orig->device_list_mutex);
575 fs_devices->total_devices = orig->total_devices;
576
577 /* We have held the volume lock, it is safe to get the devices. */
578 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
579 struct rcu_string *name;
580
581 device = btrfs_alloc_device(NULL, &orig_dev->devid,
582 orig_dev->uuid);
583 if (IS_ERR(device))
584 goto error;
585
586 /*
587 * This is ok to do without rcu read locked because we hold the
588 * uuid mutex so nothing we touch in here is going to disappear.
589 */
590 if (orig_dev->name) {
591 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
592 if (!name) {
593 kfree(device);
594 goto error;
595 }
596 rcu_assign_pointer(device->name, name);
597 }
598
599 list_add(&device->dev_list, &fs_devices->devices);
600 device->fs_devices = fs_devices;
601 fs_devices->num_devices++;
602 }
603 mutex_unlock(&orig->device_list_mutex);
604 return fs_devices;
605 error:
606 mutex_unlock(&orig->device_list_mutex);
607 free_fs_devices(fs_devices);
608 return ERR_PTR(-ENOMEM);
609 }
610
611 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step)
612 {
613 struct btrfs_device *device, *next;
614 struct btrfs_device *latest_dev = NULL;
615
616 mutex_lock(&uuid_mutex);
617 again:
618 /* This is the initialized path, it is safe to release the devices. */
619 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
620 if (device->in_fs_metadata) {
621 if (!device->is_tgtdev_for_dev_replace &&
622 (!latest_dev ||
623 device->generation > latest_dev->generation)) {
624 latest_dev = device;
625 }
626 continue;
627 }
628
629 if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
630 /*
631 * In the first step, keep the device which has
632 * the correct fsid and the devid that is used
633 * for the dev_replace procedure.
634 * In the second step, the dev_replace state is
635 * read from the device tree and it is known
636 * whether the procedure is really active or
637 * not, which means whether this device is
638 * used or whether it should be removed.
639 */
640 if (step == 0 || device->is_tgtdev_for_dev_replace) {
641 continue;
642 }
643 }
644 if (device->bdev) {
645 blkdev_put(device->bdev, device->mode);
646 device->bdev = NULL;
647 fs_devices->open_devices--;
648 }
649 if (device->writeable) {
650 list_del_init(&device->dev_alloc_list);
651 device->writeable = 0;
652 if (!device->is_tgtdev_for_dev_replace)
653 fs_devices->rw_devices--;
654 }
655 list_del_init(&device->dev_list);
656 fs_devices->num_devices--;
657 rcu_string_free(device->name);
658 kfree(device);
659 }
660
661 if (fs_devices->seed) {
662 fs_devices = fs_devices->seed;
663 goto again;
664 }
665
666 fs_devices->latest_bdev = latest_dev->bdev;
667
668 mutex_unlock(&uuid_mutex);
669 }
670
671 static void __free_device(struct work_struct *work)
672 {
673 struct btrfs_device *device;
674
675 device = container_of(work, struct btrfs_device, rcu_work);
676
677 if (device->bdev)
678 blkdev_put(device->bdev, device->mode);
679
680 rcu_string_free(device->name);
681 kfree(device);
682 }
683
684 static void free_device(struct rcu_head *head)
685 {
686 struct btrfs_device *device;
687
688 device = container_of(head, struct btrfs_device, rcu);
689
690 INIT_WORK(&device->rcu_work, __free_device);
691 schedule_work(&device->rcu_work);
692 }
693
694 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
695 {
696 struct btrfs_device *device;
697
698 if (--fs_devices->opened > 0)
699 return 0;
700
701 mutex_lock(&fs_devices->device_list_mutex);
702 list_for_each_entry(device, &fs_devices->devices, dev_list) {
703 struct btrfs_device *new_device;
704 struct rcu_string *name;
705
706 if (device->bdev)
707 fs_devices->open_devices--;
708
709 if (device->writeable &&
710 device->devid != BTRFS_DEV_REPLACE_DEVID) {
711 list_del_init(&device->dev_alloc_list);
712 fs_devices->rw_devices--;
713 }
714
715 if (device->missing)
716 fs_devices->missing_devices--;
717
718 new_device = btrfs_alloc_device(NULL, &device->devid,
719 device->uuid);
720 BUG_ON(IS_ERR(new_device)); /* -ENOMEM */
721
722 /* Safe because we are under uuid_mutex */
723 if (device->name) {
724 name = rcu_string_strdup(device->name->str, GFP_NOFS);
725 BUG_ON(!name); /* -ENOMEM */
726 rcu_assign_pointer(new_device->name, name);
727 }
728
729 list_replace_rcu(&device->dev_list, &new_device->dev_list);
730 new_device->fs_devices = device->fs_devices;
731
732 call_rcu(&device->rcu, free_device);
733 }
734 mutex_unlock(&fs_devices->device_list_mutex);
735
736 WARN_ON(fs_devices->open_devices);
737 WARN_ON(fs_devices->rw_devices);
738 fs_devices->opened = 0;
739 fs_devices->seeding = 0;
740
741 return 0;
742 }
743
744 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
745 {
746 struct btrfs_fs_devices *seed_devices = NULL;
747 int ret;
748
749 mutex_lock(&uuid_mutex);
750 ret = __btrfs_close_devices(fs_devices);
751 if (!fs_devices->opened) {
752 seed_devices = fs_devices->seed;
753 fs_devices->seed = NULL;
754 }
755 mutex_unlock(&uuid_mutex);
756
757 while (seed_devices) {
758 fs_devices = seed_devices;
759 seed_devices = fs_devices->seed;
760 __btrfs_close_devices(fs_devices);
761 free_fs_devices(fs_devices);
762 }
763 /*
764 * Wait for rcu kworkers under __btrfs_close_devices
765 * to finish all blkdev_puts so device is really
766 * free when umount is done.
767 */
768 rcu_barrier();
769 return ret;
770 }
771
772 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
773 fmode_t flags, void *holder)
774 {
775 struct request_queue *q;
776 struct block_device *bdev;
777 struct list_head *head = &fs_devices->devices;
778 struct btrfs_device *device;
779 struct btrfs_device *latest_dev = NULL;
780 struct buffer_head *bh;
781 struct btrfs_super_block *disk_super;
782 u64 devid;
783 int seeding = 1;
784 int ret = 0;
785
786 flags |= FMODE_EXCL;
787
788 list_for_each_entry(device, head, dev_list) {
789 if (device->bdev)
790 continue;
791 if (!device->name)
792 continue;
793
794 /* Just open everything we can; ignore failures here */
795 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
796 &bdev, &bh))
797 continue;
798
799 disk_super = (struct btrfs_super_block *)bh->b_data;
800 devid = btrfs_stack_device_id(&disk_super->dev_item);
801 if (devid != device->devid)
802 goto error_brelse;
803
804 if (memcmp(device->uuid, disk_super->dev_item.uuid,
805 BTRFS_UUID_SIZE))
806 goto error_brelse;
807
808 device->generation = btrfs_super_generation(disk_super);
809 if (!latest_dev ||
810 device->generation > latest_dev->generation)
811 latest_dev = device;
812
813 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
814 device->writeable = 0;
815 } else {
816 device->writeable = !bdev_read_only(bdev);
817 seeding = 0;
818 }
819
820 q = bdev_get_queue(bdev);
821 if (blk_queue_discard(q))
822 device->can_discard = 1;
823
824 device->bdev = bdev;
825 device->in_fs_metadata = 0;
826 device->mode = flags;
827
828 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
829 fs_devices->rotating = 1;
830
831 fs_devices->open_devices++;
832 if (device->writeable &&
833 device->devid != BTRFS_DEV_REPLACE_DEVID) {
834 fs_devices->rw_devices++;
835 list_add(&device->dev_alloc_list,
836 &fs_devices->alloc_list);
837 }
838 brelse(bh);
839 continue;
840
841 error_brelse:
842 brelse(bh);
843 blkdev_put(bdev, flags);
844 continue;
845 }
846 if (fs_devices->open_devices == 0) {
847 ret = -EINVAL;
848 goto out;
849 }
850 fs_devices->seeding = seeding;
851 fs_devices->opened = 1;
852 fs_devices->latest_bdev = latest_dev->bdev;
853 fs_devices->total_rw_bytes = 0;
854 out:
855 return ret;
856 }
857
858 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
859 fmode_t flags, void *holder)
860 {
861 int ret;
862
863 mutex_lock(&uuid_mutex);
864 if (fs_devices->opened) {
865 fs_devices->opened++;
866 ret = 0;
867 } else {
868 ret = __btrfs_open_devices(fs_devices, flags, holder);
869 }
870 mutex_unlock(&uuid_mutex);
871 return ret;
872 }
873
874 /*
875 * Look for a btrfs signature on a device. This may be called out of the mount path
876 * and we are not allowed to call set_blocksize during the scan. The superblock
877 * is read via pagecache
878 */
879 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
880 struct btrfs_fs_devices **fs_devices_ret)
881 {
882 struct btrfs_super_block *disk_super;
883 struct block_device *bdev;
884 struct page *page;
885 void *p;
886 int ret = -EINVAL;
887 u64 devid;
888 u64 transid;
889 u64 total_devices;
890 u64 bytenr;
891 pgoff_t index;
892
893 /*
894 * we would like to check all the supers, but that would make
895 * a btrfs mount succeed after a mkfs from a different FS.
896 * So, we need to add a special mount option to scan for
897 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
898 */
899 bytenr = btrfs_sb_offset(0);
900 flags |= FMODE_EXCL;
901 mutex_lock(&uuid_mutex);
902
903 bdev = blkdev_get_by_path(path, flags, holder);
904
905 if (IS_ERR(bdev)) {
906 ret = PTR_ERR(bdev);
907 goto error;
908 }
909
910 /* make sure our super fits in the device */
911 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode))
912 goto error_bdev_put;
913
914 /* make sure our super fits in the page */
915 if (sizeof(*disk_super) > PAGE_CACHE_SIZE)
916 goto error_bdev_put;
917
918 /* make sure our super doesn't straddle pages on disk */
919 index = bytenr >> PAGE_CACHE_SHIFT;
920 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index)
921 goto error_bdev_put;
922
923 /* pull in the page with our super */
924 page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
925 index, GFP_NOFS);
926
927 if (IS_ERR_OR_NULL(page))
928 goto error_bdev_put;
929
930 p = kmap(page);
931
932 /* align our pointer to the offset of the super block */
933 disk_super = p + (bytenr & ~PAGE_CACHE_MASK);
934
935 if (btrfs_super_bytenr(disk_super) != bytenr ||
936 btrfs_super_magic(disk_super) != BTRFS_MAGIC)
937 goto error_unmap;
938
939 devid = btrfs_stack_device_id(&disk_super->dev_item);
940 transid = btrfs_super_generation(disk_super);
941 total_devices = btrfs_super_num_devices(disk_super);
942
943 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
944 if (ret > 0) {
945 if (disk_super->label[0]) {
946 if (disk_super->label[BTRFS_LABEL_SIZE - 1])
947 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
948 printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
949 } else {
950 printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
951 }
952
953 printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
954 ret = 0;
955 }
956 if (!ret && fs_devices_ret)
957 (*fs_devices_ret)->total_devices = total_devices;
958
959 error_unmap:
960 kunmap(page);
961 page_cache_release(page);
962
963 error_bdev_put:
964 blkdev_put(bdev, flags);
965 error:
966 mutex_unlock(&uuid_mutex);
967 return ret;
968 }
969
970 /* helper to account the used device space in the range */
971 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
972 u64 end, u64 *length)
973 {
974 struct btrfs_key key;
975 struct btrfs_root *root = device->dev_root;
976 struct btrfs_dev_extent *dev_extent;
977 struct btrfs_path *path;
978 u64 extent_end;
979 int ret;
980 int slot;
981 struct extent_buffer *l;
982
983 *length = 0;
984
985 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
986 return 0;
987
988 path = btrfs_alloc_path();
989 if (!path)
990 return -ENOMEM;
991 path->reada = 2;
992
993 key.objectid = device->devid;
994 key.offset = start;
995 key.type = BTRFS_DEV_EXTENT_KEY;
996
997 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
998 if (ret < 0)
999 goto out;
1000 if (ret > 0) {
1001 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1002 if (ret < 0)
1003 goto out;
1004 }
1005
1006 while (1) {
1007 l = path->nodes[0];
1008 slot = path->slots[0];
1009 if (slot >= btrfs_header_nritems(l)) {
1010 ret = btrfs_next_leaf(root, path);
1011 if (ret == 0)
1012 continue;
1013 if (ret < 0)
1014 goto out;
1015
1016 break;
1017 }
1018 btrfs_item_key_to_cpu(l, &key, slot);
1019
1020 if (key.objectid < device->devid)
1021 goto next;
1022
1023 if (key.objectid > device->devid)
1024 break;
1025
1026 if (key.type != BTRFS_DEV_EXTENT_KEY)
1027 goto next;
1028
1029 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1030 extent_end = key.offset + btrfs_dev_extent_length(l,
1031 dev_extent);
1032 if (key.offset <= start && extent_end > end) {
1033 *length = end - start + 1;
1034 break;
1035 } else if (key.offset <= start && extent_end > start)
1036 *length += extent_end - start;
1037 else if (key.offset > start && extent_end <= end)
1038 *length += extent_end - key.offset;
1039 else if (key.offset > start && key.offset <= end) {
1040 *length += end - key.offset + 1;
1041 break;
1042 } else if (key.offset > end)
1043 break;
1044
1045 next:
1046 path->slots[0]++;
1047 }
1048 ret = 0;
1049 out:
1050 btrfs_free_path(path);
1051 return ret;
1052 }
1053
1054 static int contains_pending_extent(struct btrfs_trans_handle *trans,
1055 struct btrfs_device *device,
1056 u64 *start, u64 len)
1057 {
1058 struct extent_map *em;
1059 struct list_head *search_list = &trans->transaction->pending_chunks;
1060 int ret = 0;
1061
1062 again:
1063 list_for_each_entry(em, search_list, list) {
1064 struct map_lookup *map;
1065 int i;
1066
1067 map = (struct map_lookup *)em->bdev;
1068 for (i = 0; i < map->num_stripes; i++) {
1069 if (map->stripes[i].dev != device)
1070 continue;
1071 if (map->stripes[i].physical >= *start + len ||
1072 map->stripes[i].physical + em->orig_block_len <=
1073 *start)
1074 continue;
1075 *start = map->stripes[i].physical +
1076 em->orig_block_len;
1077 ret = 1;
1078 }
1079 }
1080 if (search_list == &trans->transaction->pending_chunks) {
1081 search_list = &trans->root->fs_info->pinned_chunks;
1082 goto again;
1083 }
1084
1085 return ret;
1086 }
1087
1088
1089 /*
1090 * find_free_dev_extent - find free space in the specified device
1091 * @device: the device which we search the free space in
1092 * @num_bytes: the size of the free space that we need
1093 * @start: store the start of the free space.
1094 * @len: the size of the free space. that we find, or the size of the max
1095 * free space if we don't find suitable free space
1096 *
1097 * this uses a pretty simple search, the expectation is that it is
1098 * called very infrequently and that a given device has a small number
1099 * of extents
1100 *
1101 * @start is used to store the start of the free space if we find. But if we
1102 * don't find suitable free space, it will be used to store the start position
1103 * of the max free space.
1104 *
1105 * @len is used to store the size of the free space that we find.
1106 * But if we don't find suitable free space, it is used to store the size of
1107 * the max free space.
1108 */
1109 int find_free_dev_extent(struct btrfs_trans_handle *trans,
1110 struct btrfs_device *device, u64 num_bytes,
1111 u64 *start, u64 *len)
1112 {
1113 struct btrfs_key key;
1114 struct btrfs_root *root = device->dev_root;
1115 struct btrfs_dev_extent *dev_extent;
1116 struct btrfs_path *path;
1117 u64 hole_size;
1118 u64 max_hole_start;
1119 u64 max_hole_size;
1120 u64 extent_end;
1121 u64 search_start;
1122 u64 search_end = device->total_bytes;
1123 int ret;
1124 int slot;
1125 struct extent_buffer *l;
1126
1127 /* FIXME use last free of some kind */
1128
1129 /* we don't want to overwrite the superblock on the drive,
1130 * so we make sure to start at an offset of at least 1MB
1131 */
1132 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
1133
1134 path = btrfs_alloc_path();
1135 if (!path)
1136 return -ENOMEM;
1137
1138 max_hole_start = search_start;
1139 max_hole_size = 0;
1140
1141 again:
1142 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
1143 ret = -ENOSPC;
1144 goto out;
1145 }
1146
1147 path->reada = 2;
1148 path->search_commit_root = 1;
1149 path->skip_locking = 1;
1150
1151 key.objectid = device->devid;
1152 key.offset = search_start;
1153 key.type = BTRFS_DEV_EXTENT_KEY;
1154
1155 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1156 if (ret < 0)
1157 goto out;
1158 if (ret > 0) {
1159 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1160 if (ret < 0)
1161 goto out;
1162 }
1163
1164 while (1) {
1165 l = path->nodes[0];
1166 slot = path->slots[0];
1167 if (slot >= btrfs_header_nritems(l)) {
1168 ret = btrfs_next_leaf(root, path);
1169 if (ret == 0)
1170 continue;
1171 if (ret < 0)
1172 goto out;
1173
1174 break;
1175 }
1176 btrfs_item_key_to_cpu(l, &key, slot);
1177
1178 if (key.objectid < device->devid)
1179 goto next;
1180
1181 if (key.objectid > device->devid)
1182 break;
1183
1184 if (key.type != BTRFS_DEV_EXTENT_KEY)
1185 goto next;
1186
1187 if (key.offset > search_start) {
1188 hole_size = key.offset - search_start;
1189
1190 /*
1191 * Have to check before we set max_hole_start, otherwise
1192 * we could end up sending back this offset anyway.
1193 */
1194 if (contains_pending_extent(trans, device,
1195 &search_start,
1196 hole_size))
1197 hole_size = 0;
1198
1199 if (hole_size > max_hole_size) {
1200 max_hole_start = search_start;
1201 max_hole_size = hole_size;
1202 }
1203
1204 /*
1205 * If this free space is greater than which we need,
1206 * it must be the max free space that we have found
1207 * until now, so max_hole_start must point to the start
1208 * of this free space and the length of this free space
1209 * is stored in max_hole_size. Thus, we return
1210 * max_hole_start and max_hole_size and go back to the
1211 * caller.
1212 */
1213 if (hole_size >= num_bytes) {
1214 ret = 0;
1215 goto out;
1216 }
1217 }
1218
1219 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1220 extent_end = key.offset + btrfs_dev_extent_length(l,
1221 dev_extent);
1222 if (extent_end > search_start)
1223 search_start = extent_end;
1224 next:
1225 path->slots[0]++;
1226 cond_resched();
1227 }
1228
1229 /*
1230 * At this point, search_start should be the end of
1231 * allocated dev extents, and when shrinking the device,
1232 * search_end may be smaller than search_start.
1233 */
1234 if (search_end > search_start) {
1235 hole_size = search_end - search_start;
1236
1237 if (contains_pending_extent(trans, device, &search_start,
1238 hole_size)) {
1239 btrfs_release_path(path);
1240 goto again;
1241 }
1242
1243 if (hole_size > max_hole_size) {
1244 max_hole_start = search_start;
1245 max_hole_size = hole_size;
1246 }
1247 }
1248
1249 /* See above. */
1250 if (max_hole_size < num_bytes)
1251 ret = -ENOSPC;
1252 else
1253 ret = 0;
1254
1255 out:
1256 btrfs_free_path(path);
1257 *start = max_hole_start;
1258 if (len)
1259 *len = max_hole_size;
1260 return ret;
1261 }
1262
1263 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1264 struct btrfs_device *device,
1265 u64 start, u64 *dev_extent_len)
1266 {
1267 int ret;
1268 struct btrfs_path *path;
1269 struct btrfs_root *root = device->dev_root;
1270 struct btrfs_key key;
1271 struct btrfs_key found_key;
1272 struct extent_buffer *leaf = NULL;
1273 struct btrfs_dev_extent *extent = NULL;
1274
1275 path = btrfs_alloc_path();
1276 if (!path)
1277 return -ENOMEM;
1278
1279 key.objectid = device->devid;
1280 key.offset = start;
1281 key.type = BTRFS_DEV_EXTENT_KEY;
1282 again:
1283 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1284 if (ret > 0) {
1285 ret = btrfs_previous_item(root, path, key.objectid,
1286 BTRFS_DEV_EXTENT_KEY);
1287 if (ret)
1288 goto out;
1289 leaf = path->nodes[0];
1290 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1291 extent = btrfs_item_ptr(leaf, path->slots[0],
1292 struct btrfs_dev_extent);
1293 BUG_ON(found_key.offset > start || found_key.offset +
1294 btrfs_dev_extent_length(leaf, extent) < start);
1295 key = found_key;
1296 btrfs_release_path(path);
1297 goto again;
1298 } else if (ret == 0) {
1299 leaf = path->nodes[0];
1300 extent = btrfs_item_ptr(leaf, path->slots[0],
1301 struct btrfs_dev_extent);
1302 } else {
1303 btrfs_error(root->fs_info, ret, "Slot search failed");
1304 goto out;
1305 }
1306
1307 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1308
1309 ret = btrfs_del_item(trans, root, path);
1310 if (ret) {
1311 btrfs_error(root->fs_info, ret,
1312 "Failed to remove dev extent item");
1313 } else {
1314 trans->transaction->have_free_bgs = 1;
1315 }
1316 out:
1317 btrfs_free_path(path);
1318 return ret;
1319 }
1320
1321 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1322 struct btrfs_device *device,
1323 u64 chunk_tree, u64 chunk_objectid,
1324 u64 chunk_offset, u64 start, u64 num_bytes)
1325 {
1326 int ret;
1327 struct btrfs_path *path;
1328 struct btrfs_root *root = device->dev_root;
1329 struct btrfs_dev_extent *extent;
1330 struct extent_buffer *leaf;
1331 struct btrfs_key key;
1332
1333 WARN_ON(!device->in_fs_metadata);
1334 WARN_ON(device->is_tgtdev_for_dev_replace);
1335 path = btrfs_alloc_path();
1336 if (!path)
1337 return -ENOMEM;
1338
1339 key.objectid = device->devid;
1340 key.offset = start;
1341 key.type = BTRFS_DEV_EXTENT_KEY;
1342 ret = btrfs_insert_empty_item(trans, root, path, &key,
1343 sizeof(*extent));
1344 if (ret)
1345 goto out;
1346
1347 leaf = path->nodes[0];
1348 extent = btrfs_item_ptr(leaf, path->slots[0],
1349 struct btrfs_dev_extent);
1350 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1351 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1352 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1353
1354 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1355 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE);
1356
1357 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1358 btrfs_mark_buffer_dirty(leaf);
1359 out:
1360 btrfs_free_path(path);
1361 return ret;
1362 }
1363
1364 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1365 {
1366 struct extent_map_tree *em_tree;
1367 struct extent_map *em;
1368 struct rb_node *n;
1369 u64 ret = 0;
1370
1371 em_tree = &fs_info->mapping_tree.map_tree;
1372 read_lock(&em_tree->lock);
1373 n = rb_last(&em_tree->map);
1374 if (n) {
1375 em = rb_entry(n, struct extent_map, rb_node);
1376 ret = em->start + em->len;
1377 }
1378 read_unlock(&em_tree->lock);
1379
1380 return ret;
1381 }
1382
1383 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1384 u64 *devid_ret)
1385 {
1386 int ret;
1387 struct btrfs_key key;
1388 struct btrfs_key found_key;
1389 struct btrfs_path *path;
1390
1391 path = btrfs_alloc_path();
1392 if (!path)
1393 return -ENOMEM;
1394
1395 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1396 key.type = BTRFS_DEV_ITEM_KEY;
1397 key.offset = (u64)-1;
1398
1399 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1400 if (ret < 0)
1401 goto error;
1402
1403 BUG_ON(ret == 0); /* Corruption */
1404
1405 ret = btrfs_previous_item(fs_info->chunk_root, path,
1406 BTRFS_DEV_ITEMS_OBJECTID,
1407 BTRFS_DEV_ITEM_KEY);
1408 if (ret) {
1409 *devid_ret = 1;
1410 } else {
1411 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1412 path->slots[0]);
1413 *devid_ret = found_key.offset + 1;
1414 }
1415 ret = 0;
1416 error:
1417 btrfs_free_path(path);
1418 return ret;
1419 }
1420
1421 /*
1422 * the device information is stored in the chunk root
1423 * the btrfs_device struct should be fully filled in
1424 */
1425 static int btrfs_add_device(struct btrfs_trans_handle *trans,
1426 struct btrfs_root *root,
1427 struct btrfs_device *device)
1428 {
1429 int ret;
1430 struct btrfs_path *path;
1431 struct btrfs_dev_item *dev_item;
1432 struct extent_buffer *leaf;
1433 struct btrfs_key key;
1434 unsigned long ptr;
1435
1436 root = root->fs_info->chunk_root;
1437
1438 path = btrfs_alloc_path();
1439 if (!path)
1440 return -ENOMEM;
1441
1442 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1443 key.type = BTRFS_DEV_ITEM_KEY;
1444 key.offset = device->devid;
1445
1446 ret = btrfs_insert_empty_item(trans, root, path, &key,
1447 sizeof(*dev_item));
1448 if (ret)
1449 goto out;
1450
1451 leaf = path->nodes[0];
1452 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1453
1454 btrfs_set_device_id(leaf, dev_item, device->devid);
1455 btrfs_set_device_generation(leaf, dev_item, 0);
1456 btrfs_set_device_type(leaf, dev_item, device->type);
1457 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1458 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1459 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1460 btrfs_set_device_total_bytes(leaf, dev_item,
1461 btrfs_device_get_disk_total_bytes(device));
1462 btrfs_set_device_bytes_used(leaf, dev_item,
1463 btrfs_device_get_bytes_used(device));
1464 btrfs_set_device_group(leaf, dev_item, 0);
1465 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1466 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1467 btrfs_set_device_start_offset(leaf, dev_item, 0);
1468
1469 ptr = btrfs_device_uuid(dev_item);
1470 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1471 ptr = btrfs_device_fsid(dev_item);
1472 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1473 btrfs_mark_buffer_dirty(leaf);
1474
1475 ret = 0;
1476 out:
1477 btrfs_free_path(path);
1478 return ret;
1479 }
1480
1481 /*
1482 * Function to update ctime/mtime for a given device path.
1483 * Mainly used for ctime/mtime based probe like libblkid.
1484 */
1485 static void update_dev_time(char *path_name)
1486 {
1487 struct file *filp;
1488
1489 filp = filp_open(path_name, O_RDWR, 0);
1490 if (IS_ERR(filp))
1491 return;
1492 file_update_time(filp);
1493 filp_close(filp, NULL);
1494 return;
1495 }
1496
1497 static int btrfs_rm_dev_item(struct btrfs_root *root,
1498 struct btrfs_device *device)
1499 {
1500 int ret;
1501 struct btrfs_path *path;
1502 struct btrfs_key key;
1503 struct btrfs_trans_handle *trans;
1504
1505 root = root->fs_info->chunk_root;
1506
1507 path = btrfs_alloc_path();
1508 if (!path)
1509 return -ENOMEM;
1510
1511 trans = btrfs_start_transaction(root, 0);
1512 if (IS_ERR(trans)) {
1513 btrfs_free_path(path);
1514 return PTR_ERR(trans);
1515 }
1516 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1517 key.type = BTRFS_DEV_ITEM_KEY;
1518 key.offset = device->devid;
1519
1520 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1521 if (ret < 0)
1522 goto out;
1523
1524 if (ret > 0) {
1525 ret = -ENOENT;
1526 goto out;
1527 }
1528
1529 ret = btrfs_del_item(trans, root, path);
1530 if (ret)
1531 goto out;
1532 out:
1533 btrfs_free_path(path);
1534 btrfs_commit_transaction(trans, root);
1535 return ret;
1536 }
1537
1538 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1539 {
1540 struct btrfs_device *device;
1541 struct btrfs_device *next_device;
1542 struct block_device *bdev;
1543 struct buffer_head *bh = NULL;
1544 struct btrfs_super_block *disk_super;
1545 struct btrfs_fs_devices *cur_devices;
1546 u64 all_avail;
1547 u64 devid;
1548 u64 num_devices;
1549 u8 *dev_uuid;
1550 unsigned seq;
1551 int ret = 0;
1552 bool clear_super = false;
1553
1554 mutex_lock(&uuid_mutex);
1555
1556 do {
1557 seq = read_seqbegin(&root->fs_info->profiles_lock);
1558
1559 all_avail = root->fs_info->avail_data_alloc_bits |
1560 root->fs_info->avail_system_alloc_bits |
1561 root->fs_info->avail_metadata_alloc_bits;
1562 } while (read_seqretry(&root->fs_info->profiles_lock, seq));
1563
1564 num_devices = root->fs_info->fs_devices->num_devices;
1565 btrfs_dev_replace_lock(&root->fs_info->dev_replace);
1566 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1567 WARN_ON(num_devices < 1);
1568 num_devices--;
1569 }
1570 btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
1571
1572 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
1573 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
1574 goto out;
1575 }
1576
1577 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
1578 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
1579 goto out;
1580 }
1581
1582 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
1583 root->fs_info->fs_devices->rw_devices <= 2) {
1584 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
1585 goto out;
1586 }
1587 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
1588 root->fs_info->fs_devices->rw_devices <= 3) {
1589 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
1590 goto out;
1591 }
1592
1593 if (strcmp(device_path, "missing") == 0) {
1594 struct list_head *devices;
1595 struct btrfs_device *tmp;
1596
1597 device = NULL;
1598 devices = &root->fs_info->fs_devices->devices;
1599 /*
1600 * It is safe to read the devices since the volume_mutex
1601 * is held.
1602 */
1603 list_for_each_entry(tmp, devices, dev_list) {
1604 if (tmp->in_fs_metadata &&
1605 !tmp->is_tgtdev_for_dev_replace &&
1606 !tmp->bdev) {
1607 device = tmp;
1608 break;
1609 }
1610 }
1611 bdev = NULL;
1612 bh = NULL;
1613 disk_super = NULL;
1614 if (!device) {
1615 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
1616 goto out;
1617 }
1618 } else {
1619 ret = btrfs_get_bdev_and_sb(device_path,
1620 FMODE_WRITE | FMODE_EXCL,
1621 root->fs_info->bdev_holder, 0,
1622 &bdev, &bh);
1623 if (ret)
1624 goto out;
1625 disk_super = (struct btrfs_super_block *)bh->b_data;
1626 devid = btrfs_stack_device_id(&disk_super->dev_item);
1627 dev_uuid = disk_super->dev_item.uuid;
1628 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1629 disk_super->fsid);
1630 if (!device) {
1631 ret = -ENOENT;
1632 goto error_brelse;
1633 }
1634 }
1635
1636 if (device->is_tgtdev_for_dev_replace) {
1637 ret = BTRFS_ERROR_DEV_TGT_REPLACE;
1638 goto error_brelse;
1639 }
1640
1641 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1642 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
1643 goto error_brelse;
1644 }
1645
1646 if (device->writeable) {
1647 lock_chunks(root);
1648 list_del_init(&device->dev_alloc_list);
1649 device->fs_devices->rw_devices--;
1650 unlock_chunks(root);
1651 clear_super = true;
1652 }
1653
1654 mutex_unlock(&uuid_mutex);
1655 ret = btrfs_shrink_device(device, 0);
1656 mutex_lock(&uuid_mutex);
1657 if (ret)
1658 goto error_undo;
1659
1660 /*
1661 * TODO: the superblock still includes this device in its num_devices
1662 * counter although write_all_supers() is not locked out. This
1663 * could give a filesystem state which requires a degraded mount.
1664 */
1665 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1666 if (ret)
1667 goto error_undo;
1668
1669 device->in_fs_metadata = 0;
1670 btrfs_scrub_cancel_dev(root->fs_info, device);
1671
1672 /*
1673 * the device list mutex makes sure that we don't change
1674 * the device list while someone else is writing out all
1675 * the device supers. Whoever is writing all supers, should
1676 * lock the device list mutex before getting the number of
1677 * devices in the super block (super_copy). Conversely,
1678 * whoever updates the number of devices in the super block
1679 * (super_copy) should hold the device list mutex.
1680 */
1681
1682 cur_devices = device->fs_devices;
1683 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1684 list_del_rcu(&device->dev_list);
1685
1686 device->fs_devices->num_devices--;
1687 device->fs_devices->total_devices--;
1688
1689 if (device->missing)
1690 device->fs_devices->missing_devices--;
1691
1692 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1693 struct btrfs_device, dev_list);
1694 if (device->bdev == root->fs_info->sb->s_bdev)
1695 root->fs_info->sb->s_bdev = next_device->bdev;
1696 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1697 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1698
1699 if (device->bdev) {
1700 device->fs_devices->open_devices--;
1701 /* remove sysfs entry */
1702 btrfs_kobj_rm_device(root->fs_info, device);
1703 }
1704
1705 call_rcu(&device->rcu, free_device);
1706
1707 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1708 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1709 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1710
1711 if (cur_devices->open_devices == 0) {
1712 struct btrfs_fs_devices *fs_devices;
1713 fs_devices = root->fs_info->fs_devices;
1714 while (fs_devices) {
1715 if (fs_devices->seed == cur_devices) {
1716 fs_devices->seed = cur_devices->seed;
1717 break;
1718 }
1719 fs_devices = fs_devices->seed;
1720 }
1721 cur_devices->seed = NULL;
1722 __btrfs_close_devices(cur_devices);
1723 free_fs_devices(cur_devices);
1724 }
1725
1726 root->fs_info->num_tolerated_disk_barrier_failures =
1727 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1728
1729 /*
1730 * at this point, the device is zero sized. We want to
1731 * remove it from the devices list and zero out the old super
1732 */
1733 if (clear_super && disk_super) {
1734 u64 bytenr;
1735 int i;
1736
1737 /* make sure this device isn't detected as part of
1738 * the FS anymore
1739 */
1740 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1741 set_buffer_dirty(bh);
1742 sync_dirty_buffer(bh);
1743
1744 /* clear the mirror copies of super block on the disk
1745 * being removed, 0th copy is been taken care above and
1746 * the below would take of the rest
1747 */
1748 for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1749 bytenr = btrfs_sb_offset(i);
1750 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
1751 i_size_read(bdev->bd_inode))
1752 break;
1753
1754 brelse(bh);
1755 bh = __bread(bdev, bytenr / 4096,
1756 BTRFS_SUPER_INFO_SIZE);
1757 if (!bh)
1758 continue;
1759
1760 disk_super = (struct btrfs_super_block *)bh->b_data;
1761
1762 if (btrfs_super_bytenr(disk_super) != bytenr ||
1763 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1764 continue;
1765 }
1766 memset(&disk_super->magic, 0,
1767 sizeof(disk_super->magic));
1768 set_buffer_dirty(bh);
1769 sync_dirty_buffer(bh);
1770 }
1771 }
1772
1773 ret = 0;
1774
1775 if (bdev) {
1776 /* Notify udev that device has changed */
1777 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
1778
1779 /* Update ctime/mtime for device path for libblkid */
1780 update_dev_time(device_path);
1781 }
1782
1783 error_brelse:
1784 brelse(bh);
1785 if (bdev)
1786 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1787 out:
1788 mutex_unlock(&uuid_mutex);
1789 return ret;
1790 error_undo:
1791 if (device->writeable) {
1792 lock_chunks(root);
1793 list_add(&device->dev_alloc_list,
1794 &root->fs_info->fs_devices->alloc_list);
1795 device->fs_devices->rw_devices++;
1796 unlock_chunks(root);
1797 }
1798 goto error_brelse;
1799 }
1800
1801 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
1802 struct btrfs_device *srcdev)
1803 {
1804 struct btrfs_fs_devices *fs_devices;
1805
1806 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1807
1808 /*
1809 * in case of fs with no seed, srcdev->fs_devices will point
1810 * to fs_devices of fs_info. However when the dev being replaced is
1811 * a seed dev it will point to the seed's local fs_devices. In short
1812 * srcdev will have its correct fs_devices in both the cases.
1813 */
1814 fs_devices = srcdev->fs_devices;
1815
1816 list_del_rcu(&srcdev->dev_list);
1817 list_del_rcu(&srcdev->dev_alloc_list);
1818 fs_devices->num_devices--;
1819 if (srcdev->missing)
1820 fs_devices->missing_devices--;
1821
1822 if (srcdev->writeable) {
1823 fs_devices->rw_devices--;
1824 /* zero out the old super if it is writable */
1825 btrfs_scratch_superblock(srcdev);
1826 }
1827
1828 if (srcdev->bdev)
1829 fs_devices->open_devices--;
1830 }
1831
1832 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
1833 struct btrfs_device *srcdev)
1834 {
1835 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
1836
1837 call_rcu(&srcdev->rcu, free_device);
1838
1839 /*
1840 * unless fs_devices is seed fs, num_devices shouldn't go
1841 * zero
1842 */
1843 BUG_ON(!fs_devices->num_devices && !fs_devices->seeding);
1844
1845 /* if this is no devs we rather delete the fs_devices */
1846 if (!fs_devices->num_devices) {
1847 struct btrfs_fs_devices *tmp_fs_devices;
1848
1849 tmp_fs_devices = fs_info->fs_devices;
1850 while (tmp_fs_devices) {
1851 if (tmp_fs_devices->seed == fs_devices) {
1852 tmp_fs_devices->seed = fs_devices->seed;
1853 break;
1854 }
1855 tmp_fs_devices = tmp_fs_devices->seed;
1856 }
1857 fs_devices->seed = NULL;
1858 __btrfs_close_devices(fs_devices);
1859 free_fs_devices(fs_devices);
1860 }
1861 }
1862
1863 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
1864 struct btrfs_device *tgtdev)
1865 {
1866 struct btrfs_device *next_device;
1867
1868 mutex_lock(&uuid_mutex);
1869 WARN_ON(!tgtdev);
1870 mutex_lock(&fs_info->fs_devices->device_list_mutex);
1871 if (tgtdev->bdev) {
1872 btrfs_scratch_superblock(tgtdev);
1873 fs_info->fs_devices->open_devices--;
1874 }
1875 fs_info->fs_devices->num_devices--;
1876
1877 next_device = list_entry(fs_info->fs_devices->devices.next,
1878 struct btrfs_device, dev_list);
1879 if (tgtdev->bdev == fs_info->sb->s_bdev)
1880 fs_info->sb->s_bdev = next_device->bdev;
1881 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
1882 fs_info->fs_devices->latest_bdev = next_device->bdev;
1883 list_del_rcu(&tgtdev->dev_list);
1884
1885 call_rcu(&tgtdev->rcu, free_device);
1886
1887 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
1888 mutex_unlock(&uuid_mutex);
1889 }
1890
1891 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
1892 struct btrfs_device **device)
1893 {
1894 int ret = 0;
1895 struct btrfs_super_block *disk_super;
1896 u64 devid;
1897 u8 *dev_uuid;
1898 struct block_device *bdev;
1899 struct buffer_head *bh;
1900
1901 *device = NULL;
1902 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ,
1903 root->fs_info->bdev_holder, 0, &bdev, &bh);
1904 if (ret)
1905 return ret;
1906 disk_super = (struct btrfs_super_block *)bh->b_data;
1907 devid = btrfs_stack_device_id(&disk_super->dev_item);
1908 dev_uuid = disk_super->dev_item.uuid;
1909 *device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1910 disk_super->fsid);
1911 brelse(bh);
1912 if (!*device)
1913 ret = -ENOENT;
1914 blkdev_put(bdev, FMODE_READ);
1915 return ret;
1916 }
1917
1918 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
1919 char *device_path,
1920 struct btrfs_device **device)
1921 {
1922 *device = NULL;
1923 if (strcmp(device_path, "missing") == 0) {
1924 struct list_head *devices;
1925 struct btrfs_device *tmp;
1926
1927 devices = &root->fs_info->fs_devices->devices;
1928 /*
1929 * It is safe to read the devices since the volume_mutex
1930 * is held by the caller.
1931 */
1932 list_for_each_entry(tmp, devices, dev_list) {
1933 if (tmp->in_fs_metadata && !tmp->bdev) {
1934 *device = tmp;
1935 break;
1936 }
1937 }
1938
1939 if (!*device) {
1940 btrfs_err(root->fs_info, "no missing device found");
1941 return -ENOENT;
1942 }
1943
1944 return 0;
1945 } else {
1946 return btrfs_find_device_by_path(root, device_path, device);
1947 }
1948 }
1949
1950 /*
1951 * does all the dirty work required for changing file system's UUID.
1952 */
1953 static int btrfs_prepare_sprout(struct btrfs_root *root)
1954 {
1955 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1956 struct btrfs_fs_devices *old_devices;
1957 struct btrfs_fs_devices *seed_devices;
1958 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
1959 struct btrfs_device *device;
1960 u64 super_flags;
1961
1962 BUG_ON(!mutex_is_locked(&uuid_mutex));
1963 if (!fs_devices->seeding)
1964 return -EINVAL;
1965
1966 seed_devices = __alloc_fs_devices();
1967 if (IS_ERR(seed_devices))
1968 return PTR_ERR(seed_devices);
1969
1970 old_devices = clone_fs_devices(fs_devices);
1971 if (IS_ERR(old_devices)) {
1972 kfree(seed_devices);
1973 return PTR_ERR(old_devices);
1974 }
1975
1976 list_add(&old_devices->list, &fs_uuids);
1977
1978 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1979 seed_devices->opened = 1;
1980 INIT_LIST_HEAD(&seed_devices->devices);
1981 INIT_LIST_HEAD(&seed_devices->alloc_list);
1982 mutex_init(&seed_devices->device_list_mutex);
1983
1984 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1985 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
1986 synchronize_rcu);
1987 list_for_each_entry(device, &seed_devices->devices, dev_list)
1988 device->fs_devices = seed_devices;
1989
1990 lock_chunks(root);
1991 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1992 unlock_chunks(root);
1993
1994 fs_devices->seeding = 0;
1995 fs_devices->num_devices = 0;
1996 fs_devices->open_devices = 0;
1997 fs_devices->missing_devices = 0;
1998 fs_devices->rotating = 0;
1999 fs_devices->seed = seed_devices;
2000
2001 generate_random_uuid(fs_devices->fsid);
2002 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2003 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2004 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2005
2006 super_flags = btrfs_super_flags(disk_super) &
2007 ~BTRFS_SUPER_FLAG_SEEDING;
2008 btrfs_set_super_flags(disk_super, super_flags);
2009
2010 return 0;
2011 }
2012
2013 /*
2014 * strore the expected generation for seed devices in device items.
2015 */
2016 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
2017 struct btrfs_root *root)
2018 {
2019 struct btrfs_path *path;
2020 struct extent_buffer *leaf;
2021 struct btrfs_dev_item *dev_item;
2022 struct btrfs_device *device;
2023 struct btrfs_key key;
2024 u8 fs_uuid[BTRFS_UUID_SIZE];
2025 u8 dev_uuid[BTRFS_UUID_SIZE];
2026 u64 devid;
2027 int ret;
2028
2029 path = btrfs_alloc_path();
2030 if (!path)
2031 return -ENOMEM;
2032
2033 root = root->fs_info->chunk_root;
2034 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2035 key.offset = 0;
2036 key.type = BTRFS_DEV_ITEM_KEY;
2037
2038 while (1) {
2039 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2040 if (ret < 0)
2041 goto error;
2042
2043 leaf = path->nodes[0];
2044 next_slot:
2045 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2046 ret = btrfs_next_leaf(root, path);
2047 if (ret > 0)
2048 break;
2049 if (ret < 0)
2050 goto error;
2051 leaf = path->nodes[0];
2052 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2053 btrfs_release_path(path);
2054 continue;
2055 }
2056
2057 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2058 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2059 key.type != BTRFS_DEV_ITEM_KEY)
2060 break;
2061
2062 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2063 struct btrfs_dev_item);
2064 devid = btrfs_device_id(leaf, dev_item);
2065 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2066 BTRFS_UUID_SIZE);
2067 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2068 BTRFS_UUID_SIZE);
2069 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2070 fs_uuid);
2071 BUG_ON(!device); /* Logic error */
2072
2073 if (device->fs_devices->seeding) {
2074 btrfs_set_device_generation(leaf, dev_item,
2075 device->generation);
2076 btrfs_mark_buffer_dirty(leaf);
2077 }
2078
2079 path->slots[0]++;
2080 goto next_slot;
2081 }
2082 ret = 0;
2083 error:
2084 btrfs_free_path(path);
2085 return ret;
2086 }
2087
2088 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
2089 {
2090 struct request_queue *q;
2091 struct btrfs_trans_handle *trans;
2092 struct btrfs_device *device;
2093 struct block_device *bdev;
2094 struct list_head *devices;
2095 struct super_block *sb = root->fs_info->sb;
2096 struct rcu_string *name;
2097 u64 tmp;
2098 int seeding_dev = 0;
2099 int ret = 0;
2100
2101 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
2102 return -EROFS;
2103
2104 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2105 root->fs_info->bdev_holder);
2106 if (IS_ERR(bdev))
2107 return PTR_ERR(bdev);
2108
2109 if (root->fs_info->fs_devices->seeding) {
2110 seeding_dev = 1;
2111 down_write(&sb->s_umount);
2112 mutex_lock(&uuid_mutex);
2113 }
2114
2115 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2116
2117 devices = &root->fs_info->fs_devices->devices;
2118
2119 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2120 list_for_each_entry(device, devices, dev_list) {
2121 if (device->bdev == bdev) {
2122 ret = -EEXIST;
2123 mutex_unlock(
2124 &root->fs_info->fs_devices->device_list_mutex);
2125 goto error;
2126 }
2127 }
2128 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2129
2130 device = btrfs_alloc_device(root->fs_info, NULL, NULL);
2131 if (IS_ERR(device)) {
2132 /* we can safely leave the fs_devices entry around */
2133 ret = PTR_ERR(device);
2134 goto error;
2135 }
2136
2137 name = rcu_string_strdup(device_path, GFP_NOFS);
2138 if (!name) {
2139 kfree(device);
2140 ret = -ENOMEM;
2141 goto error;
2142 }
2143 rcu_assign_pointer(device->name, name);
2144
2145 trans = btrfs_start_transaction(root, 0);
2146 if (IS_ERR(trans)) {
2147 rcu_string_free(device->name);
2148 kfree(device);
2149 ret = PTR_ERR(trans);
2150 goto error;
2151 }
2152
2153 q = bdev_get_queue(bdev);
2154 if (blk_queue_discard(q))
2155 device->can_discard = 1;
2156 device->writeable = 1;
2157 device->generation = trans->transid;
2158 device->io_width = root->sectorsize;
2159 device->io_align = root->sectorsize;
2160 device->sector_size = root->sectorsize;
2161 device->total_bytes = i_size_read(bdev->bd_inode);
2162 device->disk_total_bytes = device->total_bytes;
2163 device->commit_total_bytes = device->total_bytes;
2164 device->dev_root = root->fs_info->dev_root;
2165 device->bdev = bdev;
2166 device->in_fs_metadata = 1;
2167 device->is_tgtdev_for_dev_replace = 0;
2168 device->mode = FMODE_EXCL;
2169 device->dev_stats_valid = 1;
2170 set_blocksize(device->bdev, 4096);
2171
2172 if (seeding_dev) {
2173 sb->s_flags &= ~MS_RDONLY;
2174 ret = btrfs_prepare_sprout(root);
2175 BUG_ON(ret); /* -ENOMEM */
2176 }
2177
2178 device->fs_devices = root->fs_info->fs_devices;
2179
2180 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2181 lock_chunks(root);
2182 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
2183 list_add(&device->dev_alloc_list,
2184 &root->fs_info->fs_devices->alloc_list);
2185 root->fs_info->fs_devices->num_devices++;
2186 root->fs_info->fs_devices->open_devices++;
2187 root->fs_info->fs_devices->rw_devices++;
2188 root->fs_info->fs_devices->total_devices++;
2189 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
2190
2191 spin_lock(&root->fs_info->free_chunk_lock);
2192 root->fs_info->free_chunk_space += device->total_bytes;
2193 spin_unlock(&root->fs_info->free_chunk_lock);
2194
2195 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
2196 root->fs_info->fs_devices->rotating = 1;
2197
2198 tmp = btrfs_super_total_bytes(root->fs_info->super_copy);
2199 btrfs_set_super_total_bytes(root->fs_info->super_copy,
2200 tmp + device->total_bytes);
2201
2202 tmp = btrfs_super_num_devices(root->fs_info->super_copy);
2203 btrfs_set_super_num_devices(root->fs_info->super_copy,
2204 tmp + 1);
2205
2206 /* add sysfs device entry */
2207 btrfs_kobj_add_device(root->fs_info, device);
2208
2209 /*
2210 * we've got more storage, clear any full flags on the space
2211 * infos
2212 */
2213 btrfs_clear_space_info_full(root->fs_info);
2214
2215 unlock_chunks(root);
2216 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2217
2218 if (seeding_dev) {
2219 lock_chunks(root);
2220 ret = init_first_rw_device(trans, root, device);
2221 unlock_chunks(root);
2222 if (ret) {
2223 btrfs_abort_transaction(trans, root, ret);
2224 goto error_trans;
2225 }
2226 }
2227
2228 ret = btrfs_add_device(trans, root, device);
2229 if (ret) {
2230 btrfs_abort_transaction(trans, root, ret);
2231 goto error_trans;
2232 }
2233
2234 if (seeding_dev) {
2235 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2236
2237 ret = btrfs_finish_sprout(trans, root);
2238 if (ret) {
2239 btrfs_abort_transaction(trans, root, ret);
2240 goto error_trans;
2241 }
2242
2243 /* Sprouting would change fsid of the mounted root,
2244 * so rename the fsid on the sysfs
2245 */
2246 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU",
2247 root->fs_info->fsid);
2248 if (kobject_rename(&root->fs_info->super_kobj, fsid_buf))
2249 goto error_trans;
2250 }
2251
2252 root->fs_info->num_tolerated_disk_barrier_failures =
2253 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2254 ret = btrfs_commit_transaction(trans, root);
2255
2256 if (seeding_dev) {
2257 mutex_unlock(&uuid_mutex);
2258 up_write(&sb->s_umount);
2259
2260 if (ret) /* transaction commit */
2261 return ret;
2262
2263 ret = btrfs_relocate_sys_chunks(root);
2264 if (ret < 0)
2265 btrfs_error(root->fs_info, ret,
2266 "Failed to relocate sys chunks after "
2267 "device initialization. This can be fixed "
2268 "using the \"btrfs balance\" command.");
2269 trans = btrfs_attach_transaction(root);
2270 if (IS_ERR(trans)) {
2271 if (PTR_ERR(trans) == -ENOENT)
2272 return 0;
2273 return PTR_ERR(trans);
2274 }
2275 ret = btrfs_commit_transaction(trans, root);
2276 }
2277
2278 /* Update ctime/mtime for libblkid */
2279 update_dev_time(device_path);
2280 return ret;
2281
2282 error_trans:
2283 btrfs_end_transaction(trans, root);
2284 rcu_string_free(device->name);
2285 btrfs_kobj_rm_device(root->fs_info, device);
2286 kfree(device);
2287 error:
2288 blkdev_put(bdev, FMODE_EXCL);
2289 if (seeding_dev) {
2290 mutex_unlock(&uuid_mutex);
2291 up_write(&sb->s_umount);
2292 }
2293 return ret;
2294 }
2295
2296 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2297 struct btrfs_device *srcdev,
2298 struct btrfs_device **device_out)
2299 {
2300 struct request_queue *q;
2301 struct btrfs_device *device;
2302 struct block_device *bdev;
2303 struct btrfs_fs_info *fs_info = root->fs_info;
2304 struct list_head *devices;
2305 struct rcu_string *name;
2306 u64 devid = BTRFS_DEV_REPLACE_DEVID;
2307 int ret = 0;
2308
2309 *device_out = NULL;
2310 if (fs_info->fs_devices->seeding) {
2311 btrfs_err(fs_info, "the filesystem is a seed filesystem!");
2312 return -EINVAL;
2313 }
2314
2315 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2316 fs_info->bdev_holder);
2317 if (IS_ERR(bdev)) {
2318 btrfs_err(fs_info, "target device %s is invalid!", device_path);
2319 return PTR_ERR(bdev);
2320 }
2321
2322 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2323
2324 devices = &fs_info->fs_devices->devices;
2325 list_for_each_entry(device, devices, dev_list) {
2326 if (device->bdev == bdev) {
2327 btrfs_err(fs_info, "target device is in the filesystem!");
2328 ret = -EEXIST;
2329 goto error;
2330 }
2331 }
2332
2333
2334 if (i_size_read(bdev->bd_inode) <
2335 btrfs_device_get_total_bytes(srcdev)) {
2336 btrfs_err(fs_info, "target device is smaller than source device!");
2337 ret = -EINVAL;
2338 goto error;
2339 }
2340
2341
2342 device = btrfs_alloc_device(NULL, &devid, NULL);
2343 if (IS_ERR(device)) {
2344 ret = PTR_ERR(device);
2345 goto error;
2346 }
2347
2348 name = rcu_string_strdup(device_path, GFP_NOFS);
2349 if (!name) {
2350 kfree(device);
2351 ret = -ENOMEM;
2352 goto error;
2353 }
2354 rcu_assign_pointer(device->name, name);
2355
2356 q = bdev_get_queue(bdev);
2357 if (blk_queue_discard(q))
2358 device->can_discard = 1;
2359 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2360 device->writeable = 1;
2361 device->generation = 0;
2362 device->io_width = root->sectorsize;
2363 device->io_align = root->sectorsize;
2364 device->sector_size = root->sectorsize;
2365 device->total_bytes = btrfs_device_get_total_bytes(srcdev);
2366 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev);
2367 device->bytes_used = btrfs_device_get_bytes_used(srcdev);
2368 ASSERT(list_empty(&srcdev->resized_list));
2369 device->commit_total_bytes = srcdev->commit_total_bytes;
2370 device->commit_bytes_used = device->bytes_used;
2371 device->dev_root = fs_info->dev_root;
2372 device->bdev = bdev;
2373 device->in_fs_metadata = 1;
2374 device->is_tgtdev_for_dev_replace = 1;
2375 device->mode = FMODE_EXCL;
2376 device->dev_stats_valid = 1;
2377 set_blocksize(device->bdev, 4096);
2378 device->fs_devices = fs_info->fs_devices;
2379 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2380 fs_info->fs_devices->num_devices++;
2381 fs_info->fs_devices->open_devices++;
2382 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2383
2384 *device_out = device;
2385 return ret;
2386
2387 error:
2388 blkdev_put(bdev, FMODE_EXCL);
2389 return ret;
2390 }
2391
2392 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2393 struct btrfs_device *tgtdev)
2394 {
2395 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2396 tgtdev->io_width = fs_info->dev_root->sectorsize;
2397 tgtdev->io_align = fs_info->dev_root->sectorsize;
2398 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2399 tgtdev->dev_root = fs_info->dev_root;
2400 tgtdev->in_fs_metadata = 1;
2401 }
2402
2403 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2404 struct btrfs_device *device)
2405 {
2406 int ret;
2407 struct btrfs_path *path;
2408 struct btrfs_root *root;
2409 struct btrfs_dev_item *dev_item;
2410 struct extent_buffer *leaf;
2411 struct btrfs_key key;
2412
2413 root = device->dev_root->fs_info->chunk_root;
2414
2415 path = btrfs_alloc_path();
2416 if (!path)
2417 return -ENOMEM;
2418
2419 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2420 key.type = BTRFS_DEV_ITEM_KEY;
2421 key.offset = device->devid;
2422
2423 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2424 if (ret < 0)
2425 goto out;
2426
2427 if (ret > 0) {
2428 ret = -ENOENT;
2429 goto out;
2430 }
2431
2432 leaf = path->nodes[0];
2433 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2434
2435 btrfs_set_device_id(leaf, dev_item, device->devid);
2436 btrfs_set_device_type(leaf, dev_item, device->type);
2437 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2438 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2439 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2440 btrfs_set_device_total_bytes(leaf, dev_item,
2441 btrfs_device_get_disk_total_bytes(device));
2442 btrfs_set_device_bytes_used(leaf, dev_item,
2443 btrfs_device_get_bytes_used(device));
2444 btrfs_mark_buffer_dirty(leaf);
2445
2446 out:
2447 btrfs_free_path(path);
2448 return ret;
2449 }
2450
2451 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2452 struct btrfs_device *device, u64 new_size)
2453 {
2454 struct btrfs_super_block *super_copy =
2455 device->dev_root->fs_info->super_copy;
2456 struct btrfs_fs_devices *fs_devices;
2457 u64 old_total;
2458 u64 diff;
2459
2460 if (!device->writeable)
2461 return -EACCES;
2462
2463 lock_chunks(device->dev_root);
2464 old_total = btrfs_super_total_bytes(super_copy);
2465 diff = new_size - device->total_bytes;
2466
2467 if (new_size <= device->total_bytes ||
2468 device->is_tgtdev_for_dev_replace) {
2469 unlock_chunks(device->dev_root);
2470 return -EINVAL;
2471 }
2472
2473 fs_devices = device->dev_root->fs_info->fs_devices;
2474
2475 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2476 device->fs_devices->total_rw_bytes += diff;
2477
2478 btrfs_device_set_total_bytes(device, new_size);
2479 btrfs_device_set_disk_total_bytes(device, new_size);
2480 btrfs_clear_space_info_full(device->dev_root->fs_info);
2481 if (list_empty(&device->resized_list))
2482 list_add_tail(&device->resized_list,
2483 &fs_devices->resized_devices);
2484 unlock_chunks(device->dev_root);
2485
2486 return btrfs_update_device(trans, device);
2487 }
2488
2489 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2490 struct btrfs_root *root, u64 chunk_objectid,
2491 u64 chunk_offset)
2492 {
2493 int ret;
2494 struct btrfs_path *path;
2495 struct btrfs_key key;
2496
2497 root = root->fs_info->chunk_root;
2498 path = btrfs_alloc_path();
2499 if (!path)
2500 return -ENOMEM;
2501
2502 key.objectid = chunk_objectid;
2503 key.offset = chunk_offset;
2504 key.type = BTRFS_CHUNK_ITEM_KEY;
2505
2506 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2507 if (ret < 0)
2508 goto out;
2509 else if (ret > 0) { /* Logic error or corruption */
2510 btrfs_error(root->fs_info, -ENOENT,
2511 "Failed lookup while freeing chunk.");
2512 ret = -ENOENT;
2513 goto out;
2514 }
2515
2516 ret = btrfs_del_item(trans, root, path);
2517 if (ret < 0)
2518 btrfs_error(root->fs_info, ret,
2519 "Failed to delete chunk item.");
2520 out:
2521 btrfs_free_path(path);
2522 return ret;
2523 }
2524
2525 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2526 chunk_offset)
2527 {
2528 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2529 struct btrfs_disk_key *disk_key;
2530 struct btrfs_chunk *chunk;
2531 u8 *ptr;
2532 int ret = 0;
2533 u32 num_stripes;
2534 u32 array_size;
2535 u32 len = 0;
2536 u32 cur;
2537 struct btrfs_key key;
2538
2539 lock_chunks(root);
2540 array_size = btrfs_super_sys_array_size(super_copy);
2541
2542 ptr = super_copy->sys_chunk_array;
2543 cur = 0;
2544
2545 while (cur < array_size) {
2546 disk_key = (struct btrfs_disk_key *)ptr;
2547 btrfs_disk_key_to_cpu(&key, disk_key);
2548
2549 len = sizeof(*disk_key);
2550
2551 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2552 chunk = (struct btrfs_chunk *)(ptr + len);
2553 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2554 len += btrfs_chunk_item_size(num_stripes);
2555 } else {
2556 ret = -EIO;
2557 break;
2558 }
2559 if (key.objectid == chunk_objectid &&
2560 key.offset == chunk_offset) {
2561 memmove(ptr, ptr + len, array_size - (cur + len));
2562 array_size -= len;
2563 btrfs_set_super_sys_array_size(super_copy, array_size);
2564 } else {
2565 ptr += len;
2566 cur += len;
2567 }
2568 }
2569 unlock_chunks(root);
2570 return ret;
2571 }
2572
2573 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
2574 struct btrfs_root *root, u64 chunk_offset)
2575 {
2576 struct extent_map_tree *em_tree;
2577 struct extent_map *em;
2578 struct btrfs_root *extent_root = root->fs_info->extent_root;
2579 struct map_lookup *map;
2580 u64 dev_extent_len = 0;
2581 u64 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2582 int i, ret = 0;
2583
2584 /* Just in case */
2585 root = root->fs_info->chunk_root;
2586 em_tree = &root->fs_info->mapping_tree.map_tree;
2587
2588 read_lock(&em_tree->lock);
2589 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2590 read_unlock(&em_tree->lock);
2591
2592 if (!em || em->start > chunk_offset ||
2593 em->start + em->len < chunk_offset) {
2594 /*
2595 * This is a logic error, but we don't want to just rely on the
2596 * user having built with ASSERT enabled, so if ASSERT doens't
2597 * do anything we still error out.
2598 */
2599 ASSERT(0);
2600 if (em)
2601 free_extent_map(em);
2602 return -EINVAL;
2603 }
2604 map = (struct map_lookup *)em->bdev;
2605
2606 for (i = 0; i < map->num_stripes; i++) {
2607 struct btrfs_device *device = map->stripes[i].dev;
2608 ret = btrfs_free_dev_extent(trans, device,
2609 map->stripes[i].physical,
2610 &dev_extent_len);
2611 if (ret) {
2612 btrfs_abort_transaction(trans, root, ret);
2613 goto out;
2614 }
2615
2616 if (device->bytes_used > 0) {
2617 lock_chunks(root);
2618 btrfs_device_set_bytes_used(device,
2619 device->bytes_used - dev_extent_len);
2620 spin_lock(&root->fs_info->free_chunk_lock);
2621 root->fs_info->free_chunk_space += dev_extent_len;
2622 spin_unlock(&root->fs_info->free_chunk_lock);
2623 btrfs_clear_space_info_full(root->fs_info);
2624 unlock_chunks(root);
2625 }
2626
2627 if (map->stripes[i].dev) {
2628 ret = btrfs_update_device(trans, map->stripes[i].dev);
2629 if (ret) {
2630 btrfs_abort_transaction(trans, root, ret);
2631 goto out;
2632 }
2633 }
2634 }
2635 ret = btrfs_free_chunk(trans, root, chunk_objectid, chunk_offset);
2636 if (ret) {
2637 btrfs_abort_transaction(trans, root, ret);
2638 goto out;
2639 }
2640
2641 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2642
2643 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2644 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2645 if (ret) {
2646 btrfs_abort_transaction(trans, root, ret);
2647 goto out;
2648 }
2649 }
2650
2651 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset, em);
2652 if (ret) {
2653 btrfs_abort_transaction(trans, extent_root, ret);
2654 goto out;
2655 }
2656
2657 out:
2658 /* once for us */
2659 free_extent_map(em);
2660 return ret;
2661 }
2662
2663 static int btrfs_relocate_chunk(struct btrfs_root *root,
2664 u64 chunk_objectid,
2665 u64 chunk_offset)
2666 {
2667 struct btrfs_root *extent_root;
2668 struct btrfs_trans_handle *trans;
2669 int ret;
2670
2671 root = root->fs_info->chunk_root;
2672 extent_root = root->fs_info->extent_root;
2673
2674 ret = btrfs_can_relocate(extent_root, chunk_offset);
2675 if (ret)
2676 return -ENOSPC;
2677
2678 /* step one, relocate all the extents inside this chunk */
2679 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2680 if (ret)
2681 return ret;
2682
2683 trans = btrfs_start_transaction(root, 0);
2684 if (IS_ERR(trans)) {
2685 ret = PTR_ERR(trans);
2686 btrfs_std_error(root->fs_info, ret);
2687 return ret;
2688 }
2689
2690 /*
2691 * step two, delete the device extents and the
2692 * chunk tree entries
2693 */
2694 ret = btrfs_remove_chunk(trans, root, chunk_offset);
2695 btrfs_end_transaction(trans, root);
2696 return ret;
2697 }
2698
2699 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2700 {
2701 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2702 struct btrfs_path *path;
2703 struct extent_buffer *leaf;
2704 struct btrfs_chunk *chunk;
2705 struct btrfs_key key;
2706 struct btrfs_key found_key;
2707 u64 chunk_type;
2708 bool retried = false;
2709 int failed = 0;
2710 int ret;
2711
2712 path = btrfs_alloc_path();
2713 if (!path)
2714 return -ENOMEM;
2715
2716 again:
2717 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2718 key.offset = (u64)-1;
2719 key.type = BTRFS_CHUNK_ITEM_KEY;
2720
2721 while (1) {
2722 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2723 if (ret < 0)
2724 goto error;
2725 BUG_ON(ret == 0); /* Corruption */
2726
2727 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2728 key.type);
2729 if (ret < 0)
2730 goto error;
2731 if (ret > 0)
2732 break;
2733
2734 leaf = path->nodes[0];
2735 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2736
2737 chunk = btrfs_item_ptr(leaf, path->slots[0],
2738 struct btrfs_chunk);
2739 chunk_type = btrfs_chunk_type(leaf, chunk);
2740 btrfs_release_path(path);
2741
2742 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2743 ret = btrfs_relocate_chunk(chunk_root,
2744 found_key.objectid,
2745 found_key.offset);
2746 if (ret == -ENOSPC)
2747 failed++;
2748 else
2749 BUG_ON(ret);
2750 }
2751
2752 if (found_key.offset == 0)
2753 break;
2754 key.offset = found_key.offset - 1;
2755 }
2756 ret = 0;
2757 if (failed && !retried) {
2758 failed = 0;
2759 retried = true;
2760 goto again;
2761 } else if (WARN_ON(failed && retried)) {
2762 ret = -ENOSPC;
2763 }
2764 error:
2765 btrfs_free_path(path);
2766 return ret;
2767 }
2768
2769 static int insert_balance_item(struct btrfs_root *root,
2770 struct btrfs_balance_control *bctl)
2771 {
2772 struct btrfs_trans_handle *trans;
2773 struct btrfs_balance_item *item;
2774 struct btrfs_disk_balance_args disk_bargs;
2775 struct btrfs_path *path;
2776 struct extent_buffer *leaf;
2777 struct btrfs_key key;
2778 int ret, err;
2779
2780 path = btrfs_alloc_path();
2781 if (!path)
2782 return -ENOMEM;
2783
2784 trans = btrfs_start_transaction(root, 0);
2785 if (IS_ERR(trans)) {
2786 btrfs_free_path(path);
2787 return PTR_ERR(trans);
2788 }
2789
2790 key.objectid = BTRFS_BALANCE_OBJECTID;
2791 key.type = BTRFS_BALANCE_ITEM_KEY;
2792 key.offset = 0;
2793
2794 ret = btrfs_insert_empty_item(trans, root, path, &key,
2795 sizeof(*item));
2796 if (ret)
2797 goto out;
2798
2799 leaf = path->nodes[0];
2800 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2801
2802 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2803
2804 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2805 btrfs_set_balance_data(leaf, item, &disk_bargs);
2806 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2807 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2808 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2809 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2810
2811 btrfs_set_balance_flags(leaf, item, bctl->flags);
2812
2813 btrfs_mark_buffer_dirty(leaf);
2814 out:
2815 btrfs_free_path(path);
2816 err = btrfs_commit_transaction(trans, root);
2817 if (err && !ret)
2818 ret = err;
2819 return ret;
2820 }
2821
2822 static int del_balance_item(struct btrfs_root *root)
2823 {
2824 struct btrfs_trans_handle *trans;
2825 struct btrfs_path *path;
2826 struct btrfs_key key;
2827 int ret, err;
2828
2829 path = btrfs_alloc_path();
2830 if (!path)
2831 return -ENOMEM;
2832
2833 trans = btrfs_start_transaction(root, 0);
2834 if (IS_ERR(trans)) {
2835 btrfs_free_path(path);
2836 return PTR_ERR(trans);
2837 }
2838
2839 key.objectid = BTRFS_BALANCE_OBJECTID;
2840 key.type = BTRFS_BALANCE_ITEM_KEY;
2841 key.offset = 0;
2842
2843 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2844 if (ret < 0)
2845 goto out;
2846 if (ret > 0) {
2847 ret = -ENOENT;
2848 goto out;
2849 }
2850
2851 ret = btrfs_del_item(trans, root, path);
2852 out:
2853 btrfs_free_path(path);
2854 err = btrfs_commit_transaction(trans, root);
2855 if (err && !ret)
2856 ret = err;
2857 return ret;
2858 }
2859
2860 /*
2861 * This is a heuristic used to reduce the number of chunks balanced on
2862 * resume after balance was interrupted.
2863 */
2864 static void update_balance_args(struct btrfs_balance_control *bctl)
2865 {
2866 /*
2867 * Turn on soft mode for chunk types that were being converted.
2868 */
2869 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
2870 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
2871 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
2872 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
2873 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
2874 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
2875
2876 /*
2877 * Turn on usage filter if is not already used. The idea is
2878 * that chunks that we have already balanced should be
2879 * reasonably full. Don't do it for chunks that are being
2880 * converted - that will keep us from relocating unconverted
2881 * (albeit full) chunks.
2882 */
2883 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2884 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2885 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
2886 bctl->data.usage = 90;
2887 }
2888 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2889 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2890 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
2891 bctl->sys.usage = 90;
2892 }
2893 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2894 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2895 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
2896 bctl->meta.usage = 90;
2897 }
2898 }
2899
2900 /*
2901 * Should be called with both balance and volume mutexes held to
2902 * serialize other volume operations (add_dev/rm_dev/resize) with
2903 * restriper. Same goes for unset_balance_control.
2904 */
2905 static void set_balance_control(struct btrfs_balance_control *bctl)
2906 {
2907 struct btrfs_fs_info *fs_info = bctl->fs_info;
2908
2909 BUG_ON(fs_info->balance_ctl);
2910
2911 spin_lock(&fs_info->balance_lock);
2912 fs_info->balance_ctl = bctl;
2913 spin_unlock(&fs_info->balance_lock);
2914 }
2915
2916 static void unset_balance_control(struct btrfs_fs_info *fs_info)
2917 {
2918 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
2919
2920 BUG_ON(!fs_info->balance_ctl);
2921
2922 spin_lock(&fs_info->balance_lock);
2923 fs_info->balance_ctl = NULL;
2924 spin_unlock(&fs_info->balance_lock);
2925
2926 kfree(bctl);
2927 }
2928
2929 /*
2930 * Balance filters. Return 1 if chunk should be filtered out
2931 * (should not be balanced).
2932 */
2933 static int chunk_profiles_filter(u64 chunk_type,
2934 struct btrfs_balance_args *bargs)
2935 {
2936 chunk_type = chunk_to_extended(chunk_type) &
2937 BTRFS_EXTENDED_PROFILE_MASK;
2938
2939 if (bargs->profiles & chunk_type)
2940 return 0;
2941
2942 return 1;
2943 }
2944
2945 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
2946 struct btrfs_balance_args *bargs)
2947 {
2948 struct btrfs_block_group_cache *cache;
2949 u64 chunk_used, user_thresh;
2950 int ret = 1;
2951
2952 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2953 chunk_used = btrfs_block_group_used(&cache->item);
2954
2955 if (bargs->usage == 0)
2956 user_thresh = 1;
2957 else if (bargs->usage > 100)
2958 user_thresh = cache->key.offset;
2959 else
2960 user_thresh = div_factor_fine(cache->key.offset,
2961 bargs->usage);
2962
2963 if (chunk_used < user_thresh)
2964 ret = 0;
2965
2966 btrfs_put_block_group(cache);
2967 return ret;
2968 }
2969
2970 static int chunk_devid_filter(struct extent_buffer *leaf,
2971 struct btrfs_chunk *chunk,
2972 struct btrfs_balance_args *bargs)
2973 {
2974 struct btrfs_stripe *stripe;
2975 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2976 int i;
2977
2978 for (i = 0; i < num_stripes; i++) {
2979 stripe = btrfs_stripe_nr(chunk, i);
2980 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
2981 return 0;
2982 }
2983
2984 return 1;
2985 }
2986
2987 /* [pstart, pend) */
2988 static int chunk_drange_filter(struct extent_buffer *leaf,
2989 struct btrfs_chunk *chunk,
2990 u64 chunk_offset,
2991 struct btrfs_balance_args *bargs)
2992 {
2993 struct btrfs_stripe *stripe;
2994 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2995 u64 stripe_offset;
2996 u64 stripe_length;
2997 int factor;
2998 int i;
2999
3000 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3001 return 0;
3002
3003 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
3004 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
3005 factor = num_stripes / 2;
3006 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
3007 factor = num_stripes - 1;
3008 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
3009 factor = num_stripes - 2;
3010 } else {
3011 factor = num_stripes;
3012 }
3013
3014 for (i = 0; i < num_stripes; i++) {
3015 stripe = btrfs_stripe_nr(chunk, i);
3016 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3017 continue;
3018
3019 stripe_offset = btrfs_stripe_offset(leaf, stripe);
3020 stripe_length = btrfs_chunk_length(leaf, chunk);
3021 stripe_length = div_u64(stripe_length, factor);
3022
3023 if (stripe_offset < bargs->pend &&
3024 stripe_offset + stripe_length > bargs->pstart)
3025 return 0;
3026 }
3027
3028 return 1;
3029 }
3030
3031 /* [vstart, vend) */
3032 static int chunk_vrange_filter(struct extent_buffer *leaf,
3033 struct btrfs_chunk *chunk,
3034 u64 chunk_offset,
3035 struct btrfs_balance_args *bargs)
3036 {
3037 if (chunk_offset < bargs->vend &&
3038 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
3039 /* at least part of the chunk is inside this vrange */
3040 return 0;
3041
3042 return 1;
3043 }
3044
3045 static int chunk_soft_convert_filter(u64 chunk_type,
3046 struct btrfs_balance_args *bargs)
3047 {
3048 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
3049 return 0;
3050
3051 chunk_type = chunk_to_extended(chunk_type) &
3052 BTRFS_EXTENDED_PROFILE_MASK;
3053
3054 if (bargs->target == chunk_type)
3055 return 1;
3056
3057 return 0;
3058 }
3059
3060 static int should_balance_chunk(struct btrfs_root *root,
3061 struct extent_buffer *leaf,
3062 struct btrfs_chunk *chunk, u64 chunk_offset)
3063 {
3064 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
3065 struct btrfs_balance_args *bargs = NULL;
3066 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
3067
3068 /* type filter */
3069 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
3070 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
3071 return 0;
3072 }
3073
3074 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3075 bargs = &bctl->data;
3076 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3077 bargs = &bctl->sys;
3078 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3079 bargs = &bctl->meta;
3080
3081 /* profiles filter */
3082 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
3083 chunk_profiles_filter(chunk_type, bargs)) {
3084 return 0;
3085 }
3086
3087 /* usage filter */
3088 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
3089 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
3090 return 0;
3091 }
3092
3093 /* devid filter */
3094 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
3095 chunk_devid_filter(leaf, chunk, bargs)) {
3096 return 0;
3097 }
3098
3099 /* drange filter, makes sense only with devid filter */
3100 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
3101 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
3102 return 0;
3103 }
3104
3105 /* vrange filter */
3106 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
3107 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
3108 return 0;
3109 }
3110
3111 /* soft profile changing mode */
3112 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
3113 chunk_soft_convert_filter(chunk_type, bargs)) {
3114 return 0;
3115 }
3116
3117 /*
3118 * limited by count, must be the last filter
3119 */
3120 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
3121 if (bargs->limit == 0)
3122 return 0;
3123 else
3124 bargs->limit--;
3125 }
3126
3127 return 1;
3128 }
3129
3130 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
3131 {
3132 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3133 struct btrfs_root *chunk_root = fs_info->chunk_root;
3134 struct btrfs_root *dev_root = fs_info->dev_root;
3135 struct list_head *devices;
3136 struct btrfs_device *device;
3137 u64 old_size;
3138 u64 size_to_free;
3139 struct btrfs_chunk *chunk;
3140 struct btrfs_path *path;
3141 struct btrfs_key key;
3142 struct btrfs_key found_key;
3143 struct btrfs_trans_handle *trans;
3144 struct extent_buffer *leaf;
3145 int slot;
3146 int ret;
3147 int enospc_errors = 0;
3148 bool counting = true;
3149 u64 limit_data = bctl->data.limit;
3150 u64 limit_meta = bctl->meta.limit;
3151 u64 limit_sys = bctl->sys.limit;
3152
3153 /* step one make some room on all the devices */
3154 devices = &fs_info->fs_devices->devices;
3155 list_for_each_entry(device, devices, dev_list) {
3156 old_size = btrfs_device_get_total_bytes(device);
3157 size_to_free = div_factor(old_size, 1);
3158 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
3159 if (!device->writeable ||
3160 btrfs_device_get_total_bytes(device) -
3161 btrfs_device_get_bytes_used(device) > size_to_free ||
3162 device->is_tgtdev_for_dev_replace)
3163 continue;
3164
3165 ret = btrfs_shrink_device(device, old_size - size_to_free);
3166 if (ret == -ENOSPC)
3167 break;
3168 BUG_ON(ret);
3169
3170 trans = btrfs_start_transaction(dev_root, 0);
3171 BUG_ON(IS_ERR(trans));
3172
3173 ret = btrfs_grow_device(trans, device, old_size);
3174 BUG_ON(ret);
3175
3176 btrfs_end_transaction(trans, dev_root);
3177 }
3178
3179 /* step two, relocate all the chunks */
3180 path = btrfs_alloc_path();
3181 if (!path) {
3182 ret = -ENOMEM;
3183 goto error;
3184 }
3185
3186 /* zero out stat counters */
3187 spin_lock(&fs_info->balance_lock);
3188 memset(&bctl->stat, 0, sizeof(bctl->stat));
3189 spin_unlock(&fs_info->balance_lock);
3190 again:
3191 if (!counting) {
3192 bctl->data.limit = limit_data;
3193 bctl->meta.limit = limit_meta;
3194 bctl->sys.limit = limit_sys;
3195 }
3196 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3197 key.offset = (u64)-1;
3198 key.type = BTRFS_CHUNK_ITEM_KEY;
3199
3200 while (1) {
3201 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
3202 atomic_read(&fs_info->balance_cancel_req)) {
3203 ret = -ECANCELED;
3204 goto error;
3205 }
3206
3207 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3208 if (ret < 0)
3209 goto error;
3210
3211 /*
3212 * this shouldn't happen, it means the last relocate
3213 * failed
3214 */
3215 if (ret == 0)
3216 BUG(); /* FIXME break ? */
3217
3218 ret = btrfs_previous_item(chunk_root, path, 0,
3219 BTRFS_CHUNK_ITEM_KEY);
3220 if (ret) {
3221 ret = 0;
3222 break;
3223 }
3224
3225 leaf = path->nodes[0];
3226 slot = path->slots[0];
3227 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3228
3229 if (found_key.objectid != key.objectid)
3230 break;
3231
3232 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3233
3234 if (!counting) {
3235 spin_lock(&fs_info->balance_lock);
3236 bctl->stat.considered++;
3237 spin_unlock(&fs_info->balance_lock);
3238 }
3239
3240 ret = should_balance_chunk(chunk_root, leaf, chunk,
3241 found_key.offset);
3242 btrfs_release_path(path);
3243 if (!ret)
3244 goto loop;
3245
3246 if (counting) {
3247 spin_lock(&fs_info->balance_lock);
3248 bctl->stat.expected++;
3249 spin_unlock(&fs_info->balance_lock);
3250 goto loop;
3251 }
3252
3253 ret = btrfs_relocate_chunk(chunk_root,
3254 found_key.objectid,
3255 found_key.offset);
3256 if (ret && ret != -ENOSPC)
3257 goto error;
3258 if (ret == -ENOSPC) {
3259 enospc_errors++;
3260 } else {
3261 spin_lock(&fs_info->balance_lock);
3262 bctl->stat.completed++;
3263 spin_unlock(&fs_info->balance_lock);
3264 }
3265 loop:
3266 if (found_key.offset == 0)
3267 break;
3268 key.offset = found_key.offset - 1;
3269 }
3270
3271 if (counting) {
3272 btrfs_release_path(path);
3273 counting = false;
3274 goto again;
3275 }
3276 error:
3277 btrfs_free_path(path);
3278 if (enospc_errors) {
3279 btrfs_info(fs_info, "%d enospc errors during balance",
3280 enospc_errors);
3281 if (!ret)
3282 ret = -ENOSPC;
3283 }
3284
3285 return ret;
3286 }
3287
3288 /**
3289 * alloc_profile_is_valid - see if a given profile is valid and reduced
3290 * @flags: profile to validate
3291 * @extended: if true @flags is treated as an extended profile
3292 */
3293 static int alloc_profile_is_valid(u64 flags, int extended)
3294 {
3295 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
3296 BTRFS_BLOCK_GROUP_PROFILE_MASK);
3297
3298 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
3299
3300 /* 1) check that all other bits are zeroed */
3301 if (flags & ~mask)
3302 return 0;
3303
3304 /* 2) see if profile is reduced */
3305 if (flags == 0)
3306 return !extended; /* "0" is valid for usual profiles */
3307
3308 /* true if exactly one bit set */
3309 return (flags & (flags - 1)) == 0;
3310 }
3311
3312 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
3313 {
3314 /* cancel requested || normal exit path */
3315 return atomic_read(&fs_info->balance_cancel_req) ||
3316 (atomic_read(&fs_info->balance_pause_req) == 0 &&
3317 atomic_read(&fs_info->balance_cancel_req) == 0);
3318 }
3319
3320 static void __cancel_balance(struct btrfs_fs_info *fs_info)
3321 {
3322 int ret;
3323
3324 unset_balance_control(fs_info);
3325 ret = del_balance_item(fs_info->tree_root);
3326 if (ret)
3327 btrfs_std_error(fs_info, ret);
3328
3329 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3330 }
3331
3332 /*
3333 * Should be called with both balance and volume mutexes held
3334 */
3335 int btrfs_balance(struct btrfs_balance_control *bctl,
3336 struct btrfs_ioctl_balance_args *bargs)
3337 {
3338 struct btrfs_fs_info *fs_info = bctl->fs_info;
3339 u64 allowed;
3340 int mixed = 0;
3341 int ret;
3342 u64 num_devices;
3343 unsigned seq;
3344
3345 if (btrfs_fs_closing(fs_info) ||
3346 atomic_read(&fs_info->balance_pause_req) ||
3347 atomic_read(&fs_info->balance_cancel_req)) {
3348 ret = -EINVAL;
3349 goto out;
3350 }
3351
3352 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3353 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3354 mixed = 1;
3355
3356 /*
3357 * In case of mixed groups both data and meta should be picked,
3358 * and identical options should be given for both of them.
3359 */
3360 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3361 if (mixed && (bctl->flags & allowed)) {
3362 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3363 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3364 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3365 btrfs_err(fs_info, "with mixed groups data and "
3366 "metadata balance options must be the same");
3367 ret = -EINVAL;
3368 goto out;
3369 }
3370 }
3371
3372 num_devices = fs_info->fs_devices->num_devices;
3373 btrfs_dev_replace_lock(&fs_info->dev_replace);
3374 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3375 BUG_ON(num_devices < 1);
3376 num_devices--;
3377 }
3378 btrfs_dev_replace_unlock(&fs_info->dev_replace);
3379 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3380 if (num_devices == 1)
3381 allowed |= BTRFS_BLOCK_GROUP_DUP;
3382 else if (num_devices > 1)
3383 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3384 if (num_devices > 2)
3385 allowed |= BTRFS_BLOCK_GROUP_RAID5;
3386 if (num_devices > 3)
3387 allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
3388 BTRFS_BLOCK_GROUP_RAID6);
3389 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3390 (!alloc_profile_is_valid(bctl->data.target, 1) ||
3391 (bctl->data.target & ~allowed))) {
3392 btrfs_err(fs_info, "unable to start balance with target "
3393 "data profile %llu",
3394 bctl->data.target);
3395 ret = -EINVAL;
3396 goto out;
3397 }
3398 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3399 (!alloc_profile_is_valid(bctl->meta.target, 1) ||
3400 (bctl->meta.target & ~allowed))) {
3401 btrfs_err(fs_info,
3402 "unable to start balance with target metadata profile %llu",
3403 bctl->meta.target);
3404 ret = -EINVAL;
3405 goto out;
3406 }
3407 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3408 (!alloc_profile_is_valid(bctl->sys.target, 1) ||
3409 (bctl->sys.target & ~allowed))) {
3410 btrfs_err(fs_info,
3411 "unable to start balance with target system profile %llu",
3412 bctl->sys.target);
3413 ret = -EINVAL;
3414 goto out;
3415 }
3416
3417 /* allow dup'ed data chunks only in mixed mode */
3418 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3419 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
3420 btrfs_err(fs_info, "dup for data is not allowed");
3421 ret = -EINVAL;
3422 goto out;
3423 }
3424
3425 /* allow to reduce meta or sys integrity only if force set */
3426 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3427 BTRFS_BLOCK_GROUP_RAID10 |
3428 BTRFS_BLOCK_GROUP_RAID5 |
3429 BTRFS_BLOCK_GROUP_RAID6;
3430 do {
3431 seq = read_seqbegin(&fs_info->profiles_lock);
3432
3433 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3434 (fs_info->avail_system_alloc_bits & allowed) &&
3435 !(bctl->sys.target & allowed)) ||
3436 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3437 (fs_info->avail_metadata_alloc_bits & allowed) &&
3438 !(bctl->meta.target & allowed))) {
3439 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3440 btrfs_info(fs_info, "force reducing metadata integrity");
3441 } else {
3442 btrfs_err(fs_info, "balance will reduce metadata "
3443 "integrity, use force if you want this");
3444 ret = -EINVAL;
3445 goto out;
3446 }
3447 }
3448 } while (read_seqretry(&fs_info->profiles_lock, seq));
3449
3450 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3451 int num_tolerated_disk_barrier_failures;
3452 u64 target = bctl->sys.target;
3453
3454 num_tolerated_disk_barrier_failures =
3455 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3456 if (num_tolerated_disk_barrier_failures > 0 &&
3457 (target &
3458 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 |
3459 BTRFS_AVAIL_ALLOC_BIT_SINGLE)))
3460 num_tolerated_disk_barrier_failures = 0;
3461 else if (num_tolerated_disk_barrier_failures > 1 &&
3462 (target &
3463 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)))
3464 num_tolerated_disk_barrier_failures = 1;
3465
3466 fs_info->num_tolerated_disk_barrier_failures =
3467 num_tolerated_disk_barrier_failures;
3468 }
3469
3470 ret = insert_balance_item(fs_info->tree_root, bctl);
3471 if (ret && ret != -EEXIST)
3472 goto out;
3473
3474 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3475 BUG_ON(ret == -EEXIST);
3476 set_balance_control(bctl);
3477 } else {
3478 BUG_ON(ret != -EEXIST);
3479 spin_lock(&fs_info->balance_lock);
3480 update_balance_args(bctl);
3481 spin_unlock(&fs_info->balance_lock);
3482 }
3483
3484 atomic_inc(&fs_info->balance_running);
3485 mutex_unlock(&fs_info->balance_mutex);
3486
3487 ret = __btrfs_balance(fs_info);
3488
3489 mutex_lock(&fs_info->balance_mutex);
3490 atomic_dec(&fs_info->balance_running);
3491
3492 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3493 fs_info->num_tolerated_disk_barrier_failures =
3494 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3495 }
3496
3497 if (bargs) {
3498 memset(bargs, 0, sizeof(*bargs));
3499 update_ioctl_balance_args(fs_info, 0, bargs);
3500 }
3501
3502 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3503 balance_need_close(fs_info)) {
3504 __cancel_balance(fs_info);
3505 }
3506
3507 wake_up(&fs_info->balance_wait_q);
3508
3509 return ret;
3510 out:
3511 if (bctl->flags & BTRFS_BALANCE_RESUME)
3512 __cancel_balance(fs_info);
3513 else {
3514 kfree(bctl);
3515 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3516 }
3517 return ret;
3518 }
3519
3520 static int balance_kthread(void *data)
3521 {
3522 struct btrfs_fs_info *fs_info = data;
3523 int ret = 0;
3524
3525 mutex_lock(&fs_info->volume_mutex);
3526 mutex_lock(&fs_info->balance_mutex);
3527
3528 if (fs_info->balance_ctl) {
3529 btrfs_info(fs_info, "continuing balance");
3530 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3531 }
3532
3533 mutex_unlock(&fs_info->balance_mutex);
3534 mutex_unlock(&fs_info->volume_mutex);
3535
3536 return ret;
3537 }
3538
3539 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3540 {
3541 struct task_struct *tsk;
3542
3543 spin_lock(&fs_info->balance_lock);
3544 if (!fs_info->balance_ctl) {
3545 spin_unlock(&fs_info->balance_lock);
3546 return 0;
3547 }
3548 spin_unlock(&fs_info->balance_lock);
3549
3550 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3551 btrfs_info(fs_info, "force skipping balance");
3552 return 0;
3553 }
3554
3555 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3556 return PTR_ERR_OR_ZERO(tsk);
3557 }
3558
3559 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3560 {
3561 struct btrfs_balance_control *bctl;
3562 struct btrfs_balance_item *item;
3563 struct btrfs_disk_balance_args disk_bargs;
3564 struct btrfs_path *path;
3565 struct extent_buffer *leaf;
3566 struct btrfs_key key;
3567 int ret;
3568
3569 path = btrfs_alloc_path();
3570 if (!path)
3571 return -ENOMEM;
3572
3573 key.objectid = BTRFS_BALANCE_OBJECTID;
3574 key.type = BTRFS_BALANCE_ITEM_KEY;
3575 key.offset = 0;
3576
3577 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3578 if (ret < 0)
3579 goto out;
3580 if (ret > 0) { /* ret = -ENOENT; */
3581 ret = 0;
3582 goto out;
3583 }
3584
3585 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3586 if (!bctl) {
3587 ret = -ENOMEM;
3588 goto out;
3589 }
3590
3591 leaf = path->nodes[0];
3592 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3593
3594 bctl->fs_info = fs_info;
3595 bctl->flags = btrfs_balance_flags(leaf, item);
3596 bctl->flags |= BTRFS_BALANCE_RESUME;
3597
3598 btrfs_balance_data(leaf, item, &disk_bargs);
3599 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3600 btrfs_balance_meta(leaf, item, &disk_bargs);
3601 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3602 btrfs_balance_sys(leaf, item, &disk_bargs);
3603 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3604
3605 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3606
3607 mutex_lock(&fs_info->volume_mutex);
3608 mutex_lock(&fs_info->balance_mutex);
3609
3610 set_balance_control(bctl);
3611
3612 mutex_unlock(&fs_info->balance_mutex);
3613 mutex_unlock(&fs_info->volume_mutex);
3614 out:
3615 btrfs_free_path(path);
3616 return ret;
3617 }
3618
3619 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3620 {
3621 int ret = 0;
3622
3623 mutex_lock(&fs_info->balance_mutex);
3624 if (!fs_info->balance_ctl) {
3625 mutex_unlock(&fs_info->balance_mutex);
3626 return -ENOTCONN;
3627 }
3628
3629 if (atomic_read(&fs_info->balance_running)) {
3630 atomic_inc(&fs_info->balance_pause_req);
3631 mutex_unlock(&fs_info->balance_mutex);
3632
3633 wait_event(fs_info->balance_wait_q,
3634 atomic_read(&fs_info->balance_running) == 0);
3635
3636 mutex_lock(&fs_info->balance_mutex);
3637 /* we are good with balance_ctl ripped off from under us */
3638 BUG_ON(atomic_read(&fs_info->balance_running));
3639 atomic_dec(&fs_info->balance_pause_req);
3640 } else {
3641 ret = -ENOTCONN;
3642 }
3643
3644 mutex_unlock(&fs_info->balance_mutex);
3645 return ret;
3646 }
3647
3648 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3649 {
3650 if (fs_info->sb->s_flags & MS_RDONLY)
3651 return -EROFS;
3652
3653 mutex_lock(&fs_info->balance_mutex);
3654 if (!fs_info->balance_ctl) {
3655 mutex_unlock(&fs_info->balance_mutex);
3656 return -ENOTCONN;
3657 }
3658
3659 atomic_inc(&fs_info->balance_cancel_req);
3660 /*
3661 * if we are running just wait and return, balance item is
3662 * deleted in btrfs_balance in this case
3663 */
3664 if (atomic_read(&fs_info->balance_running)) {
3665 mutex_unlock(&fs_info->balance_mutex);
3666 wait_event(fs_info->balance_wait_q,
3667 atomic_read(&fs_info->balance_running) == 0);
3668 mutex_lock(&fs_info->balance_mutex);
3669 } else {
3670 /* __cancel_balance needs volume_mutex */
3671 mutex_unlock(&fs_info->balance_mutex);
3672 mutex_lock(&fs_info->volume_mutex);
3673 mutex_lock(&fs_info->balance_mutex);
3674
3675 if (fs_info->balance_ctl)
3676 __cancel_balance(fs_info);
3677
3678 mutex_unlock(&fs_info->volume_mutex);
3679 }
3680
3681 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
3682 atomic_dec(&fs_info->balance_cancel_req);
3683 mutex_unlock(&fs_info->balance_mutex);
3684 return 0;
3685 }
3686
3687 static int btrfs_uuid_scan_kthread(void *data)
3688 {
3689 struct btrfs_fs_info *fs_info = data;
3690 struct btrfs_root *root = fs_info->tree_root;
3691 struct btrfs_key key;
3692 struct btrfs_key max_key;
3693 struct btrfs_path *path = NULL;
3694 int ret = 0;
3695 struct extent_buffer *eb;
3696 int slot;
3697 struct btrfs_root_item root_item;
3698 u32 item_size;
3699 struct btrfs_trans_handle *trans = NULL;
3700
3701 path = btrfs_alloc_path();
3702 if (!path) {
3703 ret = -ENOMEM;
3704 goto out;
3705 }
3706
3707 key.objectid = 0;
3708 key.type = BTRFS_ROOT_ITEM_KEY;
3709 key.offset = 0;
3710
3711 max_key.objectid = (u64)-1;
3712 max_key.type = BTRFS_ROOT_ITEM_KEY;
3713 max_key.offset = (u64)-1;
3714
3715 while (1) {
3716 ret = btrfs_search_forward(root, &key, path, 0);
3717 if (ret) {
3718 if (ret > 0)
3719 ret = 0;
3720 break;
3721 }
3722
3723 if (key.type != BTRFS_ROOT_ITEM_KEY ||
3724 (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
3725 key.objectid != BTRFS_FS_TREE_OBJECTID) ||
3726 key.objectid > BTRFS_LAST_FREE_OBJECTID)
3727 goto skip;
3728
3729 eb = path->nodes[0];
3730 slot = path->slots[0];
3731 item_size = btrfs_item_size_nr(eb, slot);
3732 if (item_size < sizeof(root_item))
3733 goto skip;
3734
3735 read_extent_buffer(eb, &root_item,
3736 btrfs_item_ptr_offset(eb, slot),
3737 (int)sizeof(root_item));
3738 if (btrfs_root_refs(&root_item) == 0)
3739 goto skip;
3740
3741 if (!btrfs_is_empty_uuid(root_item.uuid) ||
3742 !btrfs_is_empty_uuid(root_item.received_uuid)) {
3743 if (trans)
3744 goto update_tree;
3745
3746 btrfs_release_path(path);
3747 /*
3748 * 1 - subvol uuid item
3749 * 1 - received_subvol uuid item
3750 */
3751 trans = btrfs_start_transaction(fs_info->uuid_root, 2);
3752 if (IS_ERR(trans)) {
3753 ret = PTR_ERR(trans);
3754 break;
3755 }
3756 continue;
3757 } else {
3758 goto skip;
3759 }
3760 update_tree:
3761 if (!btrfs_is_empty_uuid(root_item.uuid)) {
3762 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3763 root_item.uuid,
3764 BTRFS_UUID_KEY_SUBVOL,
3765 key.objectid);
3766 if (ret < 0) {
3767 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3768 ret);
3769 break;
3770 }
3771 }
3772
3773 if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
3774 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3775 root_item.received_uuid,
3776 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
3777 key.objectid);
3778 if (ret < 0) {
3779 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3780 ret);
3781 break;
3782 }
3783 }
3784
3785 skip:
3786 if (trans) {
3787 ret = btrfs_end_transaction(trans, fs_info->uuid_root);
3788 trans = NULL;
3789 if (ret)
3790 break;
3791 }
3792
3793 btrfs_release_path(path);
3794 if (key.offset < (u64)-1) {
3795 key.offset++;
3796 } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
3797 key.offset = 0;
3798 key.type = BTRFS_ROOT_ITEM_KEY;
3799 } else if (key.objectid < (u64)-1) {
3800 key.offset = 0;
3801 key.type = BTRFS_ROOT_ITEM_KEY;
3802 key.objectid++;
3803 } else {
3804 break;
3805 }
3806 cond_resched();
3807 }
3808
3809 out:
3810 btrfs_free_path(path);
3811 if (trans && !IS_ERR(trans))
3812 btrfs_end_transaction(trans, fs_info->uuid_root);
3813 if (ret)
3814 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
3815 else
3816 fs_info->update_uuid_tree_gen = 1;
3817 up(&fs_info->uuid_tree_rescan_sem);
3818 return 0;
3819 }
3820
3821 /*
3822 * Callback for btrfs_uuid_tree_iterate().
3823 * returns:
3824 * 0 check succeeded, the entry is not outdated.
3825 * < 0 if an error occured.
3826 * > 0 if the check failed, which means the caller shall remove the entry.
3827 */
3828 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
3829 u8 *uuid, u8 type, u64 subid)
3830 {
3831 struct btrfs_key key;
3832 int ret = 0;
3833 struct btrfs_root *subvol_root;
3834
3835 if (type != BTRFS_UUID_KEY_SUBVOL &&
3836 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
3837 goto out;
3838
3839 key.objectid = subid;
3840 key.type = BTRFS_ROOT_ITEM_KEY;
3841 key.offset = (u64)-1;
3842 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
3843 if (IS_ERR(subvol_root)) {
3844 ret = PTR_ERR(subvol_root);
3845 if (ret == -ENOENT)
3846 ret = 1;
3847 goto out;
3848 }
3849
3850 switch (type) {
3851 case BTRFS_UUID_KEY_SUBVOL:
3852 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
3853 ret = 1;
3854 break;
3855 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
3856 if (memcmp(uuid, subvol_root->root_item.received_uuid,
3857 BTRFS_UUID_SIZE))
3858 ret = 1;
3859 break;
3860 }
3861
3862 out:
3863 return ret;
3864 }
3865
3866 static int btrfs_uuid_rescan_kthread(void *data)
3867 {
3868 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
3869 int ret;
3870
3871 /*
3872 * 1st step is to iterate through the existing UUID tree and
3873 * to delete all entries that contain outdated data.
3874 * 2nd step is to add all missing entries to the UUID tree.
3875 */
3876 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
3877 if (ret < 0) {
3878 btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
3879 up(&fs_info->uuid_tree_rescan_sem);
3880 return ret;
3881 }
3882 return btrfs_uuid_scan_kthread(data);
3883 }
3884
3885 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
3886 {
3887 struct btrfs_trans_handle *trans;
3888 struct btrfs_root *tree_root = fs_info->tree_root;
3889 struct btrfs_root *uuid_root;
3890 struct task_struct *task;
3891 int ret;
3892
3893 /*
3894 * 1 - root node
3895 * 1 - root item
3896 */
3897 trans = btrfs_start_transaction(tree_root, 2);
3898 if (IS_ERR(trans))
3899 return PTR_ERR(trans);
3900
3901 uuid_root = btrfs_create_tree(trans, fs_info,
3902 BTRFS_UUID_TREE_OBJECTID);
3903 if (IS_ERR(uuid_root)) {
3904 btrfs_abort_transaction(trans, tree_root,
3905 PTR_ERR(uuid_root));
3906 return PTR_ERR(uuid_root);
3907 }
3908
3909 fs_info->uuid_root = uuid_root;
3910
3911 ret = btrfs_commit_transaction(trans, tree_root);
3912 if (ret)
3913 return ret;
3914
3915 down(&fs_info->uuid_tree_rescan_sem);
3916 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
3917 if (IS_ERR(task)) {
3918 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3919 btrfs_warn(fs_info, "failed to start uuid_scan task");
3920 up(&fs_info->uuid_tree_rescan_sem);
3921 return PTR_ERR(task);
3922 }
3923
3924 return 0;
3925 }
3926
3927 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
3928 {
3929 struct task_struct *task;
3930
3931 down(&fs_info->uuid_tree_rescan_sem);
3932 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
3933 if (IS_ERR(task)) {
3934 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3935 btrfs_warn(fs_info, "failed to start uuid_rescan task");
3936 up(&fs_info->uuid_tree_rescan_sem);
3937 return PTR_ERR(task);
3938 }
3939
3940 return 0;
3941 }
3942
3943 /*
3944 * shrinking a device means finding all of the device extents past
3945 * the new size, and then following the back refs to the chunks.
3946 * The chunk relocation code actually frees the device extent
3947 */
3948 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
3949 {
3950 struct btrfs_trans_handle *trans;
3951 struct btrfs_root *root = device->dev_root;
3952 struct btrfs_dev_extent *dev_extent = NULL;
3953 struct btrfs_path *path;
3954 u64 length;
3955 u64 chunk_objectid;
3956 u64 chunk_offset;
3957 int ret;
3958 int slot;
3959 int failed = 0;
3960 bool retried = false;
3961 struct extent_buffer *l;
3962 struct btrfs_key key;
3963 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3964 u64 old_total = btrfs_super_total_bytes(super_copy);
3965 u64 old_size = btrfs_device_get_total_bytes(device);
3966 u64 diff = old_size - new_size;
3967
3968 if (device->is_tgtdev_for_dev_replace)
3969 return -EINVAL;
3970
3971 path = btrfs_alloc_path();
3972 if (!path)
3973 return -ENOMEM;
3974
3975 path->reada = 2;
3976
3977 lock_chunks(root);
3978
3979 btrfs_device_set_total_bytes(device, new_size);
3980 if (device->writeable) {
3981 device->fs_devices->total_rw_bytes -= diff;
3982 spin_lock(&root->fs_info->free_chunk_lock);
3983 root->fs_info->free_chunk_space -= diff;
3984 spin_unlock(&root->fs_info->free_chunk_lock);
3985 }
3986 unlock_chunks(root);
3987
3988 again:
3989 key.objectid = device->devid;
3990 key.offset = (u64)-1;
3991 key.type = BTRFS_DEV_EXTENT_KEY;
3992
3993 do {
3994 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3995 if (ret < 0)
3996 goto done;
3997
3998 ret = btrfs_previous_item(root, path, 0, key.type);
3999 if (ret < 0)
4000 goto done;
4001 if (ret) {
4002 ret = 0;
4003 btrfs_release_path(path);
4004 break;
4005 }
4006
4007 l = path->nodes[0];
4008 slot = path->slots[0];
4009 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
4010
4011 if (key.objectid != device->devid) {
4012 btrfs_release_path(path);
4013 break;
4014 }
4015
4016 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
4017 length = btrfs_dev_extent_length(l, dev_extent);
4018
4019 if (key.offset + length <= new_size) {
4020 btrfs_release_path(path);
4021 break;
4022 }
4023
4024 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
4025 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
4026 btrfs_release_path(path);
4027
4028 ret = btrfs_relocate_chunk(root, chunk_objectid, chunk_offset);
4029 if (ret && ret != -ENOSPC)
4030 goto done;
4031 if (ret == -ENOSPC)
4032 failed++;
4033 } while (key.offset-- > 0);
4034
4035 if (failed && !retried) {
4036 failed = 0;
4037 retried = true;
4038 goto again;
4039 } else if (failed && retried) {
4040 ret = -ENOSPC;
4041 lock_chunks(root);
4042
4043 btrfs_device_set_total_bytes(device, old_size);
4044 if (device->writeable)
4045 device->fs_devices->total_rw_bytes += diff;
4046 spin_lock(&root->fs_info->free_chunk_lock);
4047 root->fs_info->free_chunk_space += diff;
4048 spin_unlock(&root->fs_info->free_chunk_lock);
4049 unlock_chunks(root);
4050 goto done;
4051 }
4052
4053 /* Shrinking succeeded, else we would be at "done". */
4054 trans = btrfs_start_transaction(root, 0);
4055 if (IS_ERR(trans)) {
4056 ret = PTR_ERR(trans);
4057 goto done;
4058 }
4059
4060 lock_chunks(root);
4061 btrfs_device_set_disk_total_bytes(device, new_size);
4062 if (list_empty(&device->resized_list))
4063 list_add_tail(&device->resized_list,
4064 &root->fs_info->fs_devices->resized_devices);
4065
4066 WARN_ON(diff > old_total);
4067 btrfs_set_super_total_bytes(super_copy, old_total - diff);
4068 unlock_chunks(root);
4069
4070 /* Now btrfs_update_device() will change the on-disk size. */
4071 ret = btrfs_update_device(trans, device);
4072 btrfs_end_transaction(trans, root);
4073 done:
4074 btrfs_free_path(path);
4075 return ret;
4076 }
4077
4078 static int btrfs_add_system_chunk(struct btrfs_root *root,
4079 struct btrfs_key *key,
4080 struct btrfs_chunk *chunk, int item_size)
4081 {
4082 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4083 struct btrfs_disk_key disk_key;
4084 u32 array_size;
4085 u8 *ptr;
4086
4087 lock_chunks(root);
4088 array_size = btrfs_super_sys_array_size(super_copy);
4089 if (array_size + item_size + sizeof(disk_key)
4090 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
4091 unlock_chunks(root);
4092 return -EFBIG;
4093 }
4094
4095 ptr = super_copy->sys_chunk_array + array_size;
4096 btrfs_cpu_key_to_disk(&disk_key, key);
4097 memcpy(ptr, &disk_key, sizeof(disk_key));
4098 ptr += sizeof(disk_key);
4099 memcpy(ptr, chunk, item_size);
4100 item_size += sizeof(disk_key);
4101 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
4102 unlock_chunks(root);
4103
4104 return 0;
4105 }
4106
4107 /*
4108 * sort the devices in descending order by max_avail, total_avail
4109 */
4110 static int btrfs_cmp_device_info(const void *a, const void *b)
4111 {
4112 const struct btrfs_device_info *di_a = a;
4113 const struct btrfs_device_info *di_b = b;
4114
4115 if (di_a->max_avail > di_b->max_avail)
4116 return -1;
4117 if (di_a->max_avail < di_b->max_avail)
4118 return 1;
4119 if (di_a->total_avail > di_b->total_avail)
4120 return -1;
4121 if (di_a->total_avail < di_b->total_avail)
4122 return 1;
4123 return 0;
4124 }
4125
4126 static const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
4127 [BTRFS_RAID_RAID10] = {
4128 .sub_stripes = 2,
4129 .dev_stripes = 1,
4130 .devs_max = 0, /* 0 == as many as possible */
4131 .devs_min = 4,
4132 .devs_increment = 2,
4133 .ncopies = 2,
4134 },
4135 [BTRFS_RAID_RAID1] = {
4136 .sub_stripes = 1,
4137 .dev_stripes = 1,
4138 .devs_max = 2,
4139 .devs_min = 2,
4140 .devs_increment = 2,
4141 .ncopies = 2,
4142 },
4143 [BTRFS_RAID_DUP] = {
4144 .sub_stripes = 1,
4145 .dev_stripes = 2,
4146 .devs_max = 1,
4147 .devs_min = 1,
4148 .devs_increment = 1,
4149 .ncopies = 2,
4150 },
4151 [BTRFS_RAID_RAID0] = {
4152 .sub_stripes = 1,
4153 .dev_stripes = 1,
4154 .devs_max = 0,
4155 .devs_min = 2,
4156 .devs_increment = 1,
4157 .ncopies = 1,
4158 },
4159 [BTRFS_RAID_SINGLE] = {
4160 .sub_stripes = 1,
4161 .dev_stripes = 1,
4162 .devs_max = 1,
4163 .devs_min = 1,
4164 .devs_increment = 1,
4165 .ncopies = 1,
4166 },
4167 [BTRFS_RAID_RAID5] = {
4168 .sub_stripes = 1,
4169 .dev_stripes = 1,
4170 .devs_max = 0,
4171 .devs_min = 2,
4172 .devs_increment = 1,
4173 .ncopies = 2,
4174 },
4175 [BTRFS_RAID_RAID6] = {
4176 .sub_stripes = 1,
4177 .dev_stripes = 1,
4178 .devs_max = 0,
4179 .devs_min = 3,
4180 .devs_increment = 1,
4181 .ncopies = 3,
4182 },
4183 };
4184
4185 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
4186 {
4187 /* TODO allow them to set a preferred stripe size */
4188 return 64 * 1024;
4189 }
4190
4191 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
4192 {
4193 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
4194 return;
4195
4196 btrfs_set_fs_incompat(info, RAID56);
4197 }
4198
4199 #define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \
4200 - sizeof(struct btrfs_item) \
4201 - sizeof(struct btrfs_chunk)) \
4202 / sizeof(struct btrfs_stripe) + 1)
4203
4204 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
4205 - 2 * sizeof(struct btrfs_disk_key) \
4206 - 2 * sizeof(struct btrfs_chunk)) \
4207 / sizeof(struct btrfs_stripe) + 1)
4208
4209 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4210 struct btrfs_root *extent_root, u64 start,
4211 u64 type)
4212 {
4213 struct btrfs_fs_info *info = extent_root->fs_info;
4214 struct btrfs_fs_devices *fs_devices = info->fs_devices;
4215 struct list_head *cur;
4216 struct map_lookup *map = NULL;
4217 struct extent_map_tree *em_tree;
4218 struct extent_map *em;
4219 struct btrfs_device_info *devices_info = NULL;
4220 u64 total_avail;
4221 int num_stripes; /* total number of stripes to allocate */
4222 int data_stripes; /* number of stripes that count for
4223 block group size */
4224 int sub_stripes; /* sub_stripes info for map */
4225 int dev_stripes; /* stripes per dev */
4226 int devs_max; /* max devs to use */
4227 int devs_min; /* min devs needed */
4228 int devs_increment; /* ndevs has to be a multiple of this */
4229 int ncopies; /* how many copies to data has */
4230 int ret;
4231 u64 max_stripe_size;
4232 u64 max_chunk_size;
4233 u64 stripe_size;
4234 u64 num_bytes;
4235 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
4236 int ndevs;
4237 int i;
4238 int j;
4239 int index;
4240
4241 BUG_ON(!alloc_profile_is_valid(type, 0));
4242
4243 if (list_empty(&fs_devices->alloc_list))
4244 return -ENOSPC;
4245
4246 index = __get_raid_index(type);
4247
4248 sub_stripes = btrfs_raid_array[index].sub_stripes;
4249 dev_stripes = btrfs_raid_array[index].dev_stripes;
4250 devs_max = btrfs_raid_array[index].devs_max;
4251 devs_min = btrfs_raid_array[index].devs_min;
4252 devs_increment = btrfs_raid_array[index].devs_increment;
4253 ncopies = btrfs_raid_array[index].ncopies;
4254
4255 if (type & BTRFS_BLOCK_GROUP_DATA) {
4256 max_stripe_size = 1024 * 1024 * 1024;
4257 max_chunk_size = 10 * max_stripe_size;
4258 if (!devs_max)
4259 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4260 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
4261 /* for larger filesystems, use larger metadata chunks */
4262 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
4263 max_stripe_size = 1024 * 1024 * 1024;
4264 else
4265 max_stripe_size = 256 * 1024 * 1024;
4266 max_chunk_size = max_stripe_size;
4267 if (!devs_max)
4268 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4269 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
4270 max_stripe_size = 32 * 1024 * 1024;
4271 max_chunk_size = 2 * max_stripe_size;
4272 if (!devs_max)
4273 devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
4274 } else {
4275 btrfs_err(info, "invalid chunk type 0x%llx requested",
4276 type);
4277 BUG_ON(1);
4278 }
4279
4280 /* we don't want a chunk larger than 10% of writeable space */
4281 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
4282 max_chunk_size);
4283
4284 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
4285 GFP_NOFS);
4286 if (!devices_info)
4287 return -ENOMEM;
4288
4289 cur = fs_devices->alloc_list.next;
4290
4291 /*
4292 * in the first pass through the devices list, we gather information
4293 * about the available holes on each device.
4294 */
4295 ndevs = 0;
4296 while (cur != &fs_devices->alloc_list) {
4297 struct btrfs_device *device;
4298 u64 max_avail;
4299 u64 dev_offset;
4300
4301 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
4302
4303 cur = cur->next;
4304
4305 if (!device->writeable) {
4306 WARN(1, KERN_ERR
4307 "BTRFS: read-only device in alloc_list\n");
4308 continue;
4309 }
4310
4311 if (!device->in_fs_metadata ||
4312 device->is_tgtdev_for_dev_replace)
4313 continue;
4314
4315 if (device->total_bytes > device->bytes_used)
4316 total_avail = device->total_bytes - device->bytes_used;
4317 else
4318 total_avail = 0;
4319
4320 /* If there is no space on this device, skip it. */
4321 if (total_avail == 0)
4322 continue;
4323
4324 ret = find_free_dev_extent(trans, device,
4325 max_stripe_size * dev_stripes,
4326 &dev_offset, &max_avail);
4327 if (ret && ret != -ENOSPC)
4328 goto error;
4329
4330 if (ret == 0)
4331 max_avail = max_stripe_size * dev_stripes;
4332
4333 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
4334 continue;
4335
4336 if (ndevs == fs_devices->rw_devices) {
4337 WARN(1, "%s: found more than %llu devices\n",
4338 __func__, fs_devices->rw_devices);
4339 break;
4340 }
4341 devices_info[ndevs].dev_offset = dev_offset;
4342 devices_info[ndevs].max_avail = max_avail;
4343 devices_info[ndevs].total_avail = total_avail;
4344 devices_info[ndevs].dev = device;
4345 ++ndevs;
4346 }
4347
4348 /*
4349 * now sort the devices by hole size / available space
4350 */
4351 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
4352 btrfs_cmp_device_info, NULL);
4353
4354 /* round down to number of usable stripes */
4355 ndevs -= ndevs % devs_increment;
4356
4357 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
4358 ret = -ENOSPC;
4359 goto error;
4360 }
4361
4362 if (devs_max && ndevs > devs_max)
4363 ndevs = devs_max;
4364 /*
4365 * the primary goal is to maximize the number of stripes, so use as many
4366 * devices as possible, even if the stripes are not maximum sized.
4367 */
4368 stripe_size = devices_info[ndevs-1].max_avail;
4369 num_stripes = ndevs * dev_stripes;
4370
4371 /*
4372 * this will have to be fixed for RAID1 and RAID10 over
4373 * more drives
4374 */
4375 data_stripes = num_stripes / ncopies;
4376
4377 if (type & BTRFS_BLOCK_GROUP_RAID5) {
4378 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
4379 btrfs_super_stripesize(info->super_copy));
4380 data_stripes = num_stripes - 1;
4381 }
4382 if (type & BTRFS_BLOCK_GROUP_RAID6) {
4383 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
4384 btrfs_super_stripesize(info->super_copy));
4385 data_stripes = num_stripes - 2;
4386 }
4387
4388 /*
4389 * Use the number of data stripes to figure out how big this chunk
4390 * is really going to be in terms of logical address space,
4391 * and compare that answer with the max chunk size
4392 */
4393 if (stripe_size * data_stripes > max_chunk_size) {
4394 u64 mask = (1ULL << 24) - 1;
4395
4396 stripe_size = div_u64(max_chunk_size, data_stripes);
4397
4398 /* bump the answer up to a 16MB boundary */
4399 stripe_size = (stripe_size + mask) & ~mask;
4400
4401 /* but don't go higher than the limits we found
4402 * while searching for free extents
4403 */
4404 if (stripe_size > devices_info[ndevs-1].max_avail)
4405 stripe_size = devices_info[ndevs-1].max_avail;
4406 }
4407
4408 stripe_size = div_u64(stripe_size, dev_stripes);
4409
4410 /* align to BTRFS_STRIPE_LEN */
4411 stripe_size = div_u64(stripe_size, raid_stripe_len);
4412 stripe_size *= raid_stripe_len;
4413
4414 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4415 if (!map) {
4416 ret = -ENOMEM;
4417 goto error;
4418 }
4419 map->num_stripes = num_stripes;
4420
4421 for (i = 0; i < ndevs; ++i) {
4422 for (j = 0; j < dev_stripes; ++j) {
4423 int s = i * dev_stripes + j;
4424 map->stripes[s].dev = devices_info[i].dev;
4425 map->stripes[s].physical = devices_info[i].dev_offset +
4426 j * stripe_size;
4427 }
4428 }
4429 map->sector_size = extent_root->sectorsize;
4430 map->stripe_len = raid_stripe_len;
4431 map->io_align = raid_stripe_len;
4432 map->io_width = raid_stripe_len;
4433 map->type = type;
4434 map->sub_stripes = sub_stripes;
4435
4436 num_bytes = stripe_size * data_stripes;
4437
4438 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
4439
4440 em = alloc_extent_map();
4441 if (!em) {
4442 kfree(map);
4443 ret = -ENOMEM;
4444 goto error;
4445 }
4446 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
4447 em->bdev = (struct block_device *)map;
4448 em->start = start;
4449 em->len = num_bytes;
4450 em->block_start = 0;
4451 em->block_len = em->len;
4452 em->orig_block_len = stripe_size;
4453
4454 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4455 write_lock(&em_tree->lock);
4456 ret = add_extent_mapping(em_tree, em, 0);
4457 if (!ret) {
4458 list_add_tail(&em->list, &trans->transaction->pending_chunks);
4459 atomic_inc(&em->refs);
4460 }
4461 write_unlock(&em_tree->lock);
4462 if (ret) {
4463 free_extent_map(em);
4464 goto error;
4465 }
4466
4467 ret = btrfs_make_block_group(trans, extent_root, 0, type,
4468 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4469 start, num_bytes);
4470 if (ret)
4471 goto error_del_extent;
4472
4473 for (i = 0; i < map->num_stripes; i++) {
4474 num_bytes = map->stripes[i].dev->bytes_used + stripe_size;
4475 btrfs_device_set_bytes_used(map->stripes[i].dev, num_bytes);
4476 }
4477
4478 spin_lock(&extent_root->fs_info->free_chunk_lock);
4479 extent_root->fs_info->free_chunk_space -= (stripe_size *
4480 map->num_stripes);
4481 spin_unlock(&extent_root->fs_info->free_chunk_lock);
4482
4483 free_extent_map(em);
4484 check_raid56_incompat_flag(extent_root->fs_info, type);
4485
4486 kfree(devices_info);
4487 return 0;
4488
4489 error_del_extent:
4490 write_lock(&em_tree->lock);
4491 remove_extent_mapping(em_tree, em);
4492 write_unlock(&em_tree->lock);
4493
4494 /* One for our allocation */
4495 free_extent_map(em);
4496 /* One for the tree reference */
4497 free_extent_map(em);
4498 /* One for the pending_chunks list reference */
4499 free_extent_map(em);
4500 error:
4501 kfree(devices_info);
4502 return ret;
4503 }
4504
4505 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
4506 struct btrfs_root *extent_root,
4507 u64 chunk_offset, u64 chunk_size)
4508 {
4509 struct btrfs_key key;
4510 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
4511 struct btrfs_device *device;
4512 struct btrfs_chunk *chunk;
4513 struct btrfs_stripe *stripe;
4514 struct extent_map_tree *em_tree;
4515 struct extent_map *em;
4516 struct map_lookup *map;
4517 size_t item_size;
4518 u64 dev_offset;
4519 u64 stripe_size;
4520 int i = 0;
4521 int ret;
4522
4523 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4524 read_lock(&em_tree->lock);
4525 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
4526 read_unlock(&em_tree->lock);
4527
4528 if (!em) {
4529 btrfs_crit(extent_root->fs_info, "unable to find logical "
4530 "%Lu len %Lu", chunk_offset, chunk_size);
4531 return -EINVAL;
4532 }
4533
4534 if (em->start != chunk_offset || em->len != chunk_size) {
4535 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted"
4536 " %Lu-%Lu, found %Lu-%Lu", chunk_offset,
4537 chunk_size, em->start, em->len);
4538 free_extent_map(em);
4539 return -EINVAL;
4540 }
4541
4542 map = (struct map_lookup *)em->bdev;
4543 item_size = btrfs_chunk_item_size(map->num_stripes);
4544 stripe_size = em->orig_block_len;
4545
4546 chunk = kzalloc(item_size, GFP_NOFS);
4547 if (!chunk) {
4548 ret = -ENOMEM;
4549 goto out;
4550 }
4551
4552 for (i = 0; i < map->num_stripes; i++) {
4553 device = map->stripes[i].dev;
4554 dev_offset = map->stripes[i].physical;
4555
4556 ret = btrfs_update_device(trans, device);
4557 if (ret)
4558 goto out;
4559 ret = btrfs_alloc_dev_extent(trans, device,
4560 chunk_root->root_key.objectid,
4561 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4562 chunk_offset, dev_offset,
4563 stripe_size);
4564 if (ret)
4565 goto out;
4566 }
4567
4568 stripe = &chunk->stripe;
4569 for (i = 0; i < map->num_stripes; i++) {
4570 device = map->stripes[i].dev;
4571 dev_offset = map->stripes[i].physical;
4572
4573 btrfs_set_stack_stripe_devid(stripe, device->devid);
4574 btrfs_set_stack_stripe_offset(stripe, dev_offset);
4575 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
4576 stripe++;
4577 }
4578
4579 btrfs_set_stack_chunk_length(chunk, chunk_size);
4580 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
4581 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
4582 btrfs_set_stack_chunk_type(chunk, map->type);
4583 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
4584 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
4585 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
4586 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
4587 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
4588
4589 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4590 key.type = BTRFS_CHUNK_ITEM_KEY;
4591 key.offset = chunk_offset;
4592
4593 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
4594 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
4595 /*
4596 * TODO: Cleanup of inserted chunk root in case of
4597 * failure.
4598 */
4599 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
4600 item_size);
4601 }
4602
4603 out:
4604 kfree(chunk);
4605 free_extent_map(em);
4606 return ret;
4607 }
4608
4609 /*
4610 * Chunk allocation falls into two parts. The first part does works
4611 * that make the new allocated chunk useable, but not do any operation
4612 * that modifies the chunk tree. The second part does the works that
4613 * require modifying the chunk tree. This division is important for the
4614 * bootstrap process of adding storage to a seed btrfs.
4615 */
4616 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4617 struct btrfs_root *extent_root, u64 type)
4618 {
4619 u64 chunk_offset;
4620
4621 chunk_offset = find_next_chunk(extent_root->fs_info);
4622 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type);
4623 }
4624
4625 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
4626 struct btrfs_root *root,
4627 struct btrfs_device *device)
4628 {
4629 u64 chunk_offset;
4630 u64 sys_chunk_offset;
4631 u64 alloc_profile;
4632 struct btrfs_fs_info *fs_info = root->fs_info;
4633 struct btrfs_root *extent_root = fs_info->extent_root;
4634 int ret;
4635
4636 chunk_offset = find_next_chunk(fs_info);
4637 alloc_profile = btrfs_get_alloc_profile(extent_root, 0);
4638 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset,
4639 alloc_profile);
4640 if (ret)
4641 return ret;
4642
4643 sys_chunk_offset = find_next_chunk(root->fs_info);
4644 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
4645 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset,
4646 alloc_profile);
4647 return ret;
4648 }
4649
4650 static inline int btrfs_chunk_max_errors(struct map_lookup *map)
4651 {
4652 int max_errors;
4653
4654 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
4655 BTRFS_BLOCK_GROUP_RAID10 |
4656 BTRFS_BLOCK_GROUP_RAID5 |
4657 BTRFS_BLOCK_GROUP_DUP)) {
4658 max_errors = 1;
4659 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
4660 max_errors = 2;
4661 } else {
4662 max_errors = 0;
4663 }
4664
4665 return max_errors;
4666 }
4667
4668 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
4669 {
4670 struct extent_map *em;
4671 struct map_lookup *map;
4672 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4673 int readonly = 0;
4674 int miss_ndevs = 0;
4675 int i;
4676
4677 read_lock(&map_tree->map_tree.lock);
4678 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
4679 read_unlock(&map_tree->map_tree.lock);
4680 if (!em)
4681 return 1;
4682
4683 map = (struct map_lookup *)em->bdev;
4684 for (i = 0; i < map->num_stripes; i++) {
4685 if (map->stripes[i].dev->missing) {
4686 miss_ndevs++;
4687 continue;
4688 }
4689
4690 if (!map->stripes[i].dev->writeable) {
4691 readonly = 1;
4692 goto end;
4693 }
4694 }
4695
4696 /*
4697 * If the number of missing devices is larger than max errors,
4698 * we can not write the data into that chunk successfully, so
4699 * set it readonly.
4700 */
4701 if (miss_ndevs > btrfs_chunk_max_errors(map))
4702 readonly = 1;
4703 end:
4704 free_extent_map(em);
4705 return readonly;
4706 }
4707
4708 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
4709 {
4710 extent_map_tree_init(&tree->map_tree);
4711 }
4712
4713 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
4714 {
4715 struct extent_map *em;
4716
4717 while (1) {
4718 write_lock(&tree->map_tree.lock);
4719 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
4720 if (em)
4721 remove_extent_mapping(&tree->map_tree, em);
4722 write_unlock(&tree->map_tree.lock);
4723 if (!em)
4724 break;
4725 /* once for us */
4726 free_extent_map(em);
4727 /* once for the tree */
4728 free_extent_map(em);
4729 }
4730 }
4731
4732 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
4733 {
4734 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4735 struct extent_map *em;
4736 struct map_lookup *map;
4737 struct extent_map_tree *em_tree = &map_tree->map_tree;
4738 int ret;
4739
4740 read_lock(&em_tree->lock);
4741 em = lookup_extent_mapping(em_tree, logical, len);
4742 read_unlock(&em_tree->lock);
4743
4744 /*
4745 * We could return errors for these cases, but that could get ugly and
4746 * we'd probably do the same thing which is just not do anything else
4747 * and exit, so return 1 so the callers don't try to use other copies.
4748 */
4749 if (!em) {
4750 btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
4751 logical+len);
4752 return 1;
4753 }
4754
4755 if (em->start > logical || em->start + em->len < logical) {
4756 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got "
4757 "%Lu-%Lu", logical, logical+len, em->start,
4758 em->start + em->len);
4759 free_extent_map(em);
4760 return 1;
4761 }
4762
4763 map = (struct map_lookup *)em->bdev;
4764 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
4765 ret = map->num_stripes;
4766 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
4767 ret = map->sub_stripes;
4768 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
4769 ret = 2;
4770 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
4771 ret = 3;
4772 else
4773 ret = 1;
4774 free_extent_map(em);
4775
4776 btrfs_dev_replace_lock(&fs_info->dev_replace);
4777 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
4778 ret++;
4779 btrfs_dev_replace_unlock(&fs_info->dev_replace);
4780
4781 return ret;
4782 }
4783
4784 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
4785 struct btrfs_mapping_tree *map_tree,
4786 u64 logical)
4787 {
4788 struct extent_map *em;
4789 struct map_lookup *map;
4790 struct extent_map_tree *em_tree = &map_tree->map_tree;
4791 unsigned long len = root->sectorsize;
4792
4793 read_lock(&em_tree->lock);
4794 em = lookup_extent_mapping(em_tree, logical, len);
4795 read_unlock(&em_tree->lock);
4796 BUG_ON(!em);
4797
4798 BUG_ON(em->start > logical || em->start + em->len < logical);
4799 map = (struct map_lookup *)em->bdev;
4800 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
4801 len = map->stripe_len * nr_data_stripes(map);
4802 free_extent_map(em);
4803 return len;
4804 }
4805
4806 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
4807 u64 logical, u64 len, int mirror_num)
4808 {
4809 struct extent_map *em;
4810 struct map_lookup *map;
4811 struct extent_map_tree *em_tree = &map_tree->map_tree;
4812 int ret = 0;
4813
4814 read_lock(&em_tree->lock);
4815 em = lookup_extent_mapping(em_tree, logical, len);
4816 read_unlock(&em_tree->lock);
4817 BUG_ON(!em);
4818
4819 BUG_ON(em->start > logical || em->start + em->len < logical);
4820 map = (struct map_lookup *)em->bdev;
4821 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
4822 ret = 1;
4823 free_extent_map(em);
4824 return ret;
4825 }
4826
4827 static int find_live_mirror(struct btrfs_fs_info *fs_info,
4828 struct map_lookup *map, int first, int num,
4829 int optimal, int dev_replace_is_ongoing)
4830 {
4831 int i;
4832 int tolerance;
4833 struct btrfs_device *srcdev;
4834
4835 if (dev_replace_is_ongoing &&
4836 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
4837 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
4838 srcdev = fs_info->dev_replace.srcdev;
4839 else
4840 srcdev = NULL;
4841
4842 /*
4843 * try to avoid the drive that is the source drive for a
4844 * dev-replace procedure, only choose it if no other non-missing
4845 * mirror is available
4846 */
4847 for (tolerance = 0; tolerance < 2; tolerance++) {
4848 if (map->stripes[optimal].dev->bdev &&
4849 (tolerance || map->stripes[optimal].dev != srcdev))
4850 return optimal;
4851 for (i = first; i < first + num; i++) {
4852 if (map->stripes[i].dev->bdev &&
4853 (tolerance || map->stripes[i].dev != srcdev))
4854 return i;
4855 }
4856 }
4857
4858 /* we couldn't find one that doesn't fail. Just return something
4859 * and the io error handling code will clean up eventually
4860 */
4861 return optimal;
4862 }
4863
4864 static inline int parity_smaller(u64 a, u64 b)
4865 {
4866 return a > b;
4867 }
4868
4869 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
4870 static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes)
4871 {
4872 struct btrfs_bio_stripe s;
4873 int i;
4874 u64 l;
4875 int again = 1;
4876
4877 while (again) {
4878 again = 0;
4879 for (i = 0; i < num_stripes - 1; i++) {
4880 if (parity_smaller(bbio->raid_map[i],
4881 bbio->raid_map[i+1])) {
4882 s = bbio->stripes[i];
4883 l = bbio->raid_map[i];
4884 bbio->stripes[i] = bbio->stripes[i+1];
4885 bbio->raid_map[i] = bbio->raid_map[i+1];
4886 bbio->stripes[i+1] = s;
4887 bbio->raid_map[i+1] = l;
4888
4889 again = 1;
4890 }
4891 }
4892 }
4893 }
4894
4895 static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
4896 {
4897 struct btrfs_bio *bbio = kzalloc(
4898 /* the size of the btrfs_bio */
4899 sizeof(struct btrfs_bio) +
4900 /* plus the variable array for the stripes */
4901 sizeof(struct btrfs_bio_stripe) * (total_stripes) +
4902 /* plus the variable array for the tgt dev */
4903 sizeof(int) * (real_stripes) +
4904 /*
4905 * plus the raid_map, which includes both the tgt dev
4906 * and the stripes
4907 */
4908 sizeof(u64) * (total_stripes),
4909 GFP_NOFS);
4910 if (!bbio)
4911 return NULL;
4912
4913 atomic_set(&bbio->error, 0);
4914 atomic_set(&bbio->refs, 1);
4915
4916 return bbio;
4917 }
4918
4919 void btrfs_get_bbio(struct btrfs_bio *bbio)
4920 {
4921 WARN_ON(!atomic_read(&bbio->refs));
4922 atomic_inc(&bbio->refs);
4923 }
4924
4925 void btrfs_put_bbio(struct btrfs_bio *bbio)
4926 {
4927 if (!bbio)
4928 return;
4929 if (atomic_dec_and_test(&bbio->refs))
4930 kfree(bbio);
4931 }
4932
4933 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
4934 u64 logical, u64 *length,
4935 struct btrfs_bio **bbio_ret,
4936 int mirror_num, int need_raid_map)
4937 {
4938 struct extent_map *em;
4939 struct map_lookup *map;
4940 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4941 struct extent_map_tree *em_tree = &map_tree->map_tree;
4942 u64 offset;
4943 u64 stripe_offset;
4944 u64 stripe_end_offset;
4945 u64 stripe_nr;
4946 u64 stripe_nr_orig;
4947 u64 stripe_nr_end;
4948 u64 stripe_len;
4949 u32 stripe_index;
4950 int i;
4951 int ret = 0;
4952 int num_stripes;
4953 int max_errors = 0;
4954 int tgtdev_indexes = 0;
4955 struct btrfs_bio *bbio = NULL;
4956 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
4957 int dev_replace_is_ongoing = 0;
4958 int num_alloc_stripes;
4959 int patch_the_first_stripe_for_dev_replace = 0;
4960 u64 physical_to_patch_in_first_stripe = 0;
4961 u64 raid56_full_stripe_start = (u64)-1;
4962
4963 read_lock(&em_tree->lock);
4964 em = lookup_extent_mapping(em_tree, logical, *length);
4965 read_unlock(&em_tree->lock);
4966
4967 if (!em) {
4968 btrfs_crit(fs_info, "unable to find logical %llu len %llu",
4969 logical, *length);
4970 return -EINVAL;
4971 }
4972
4973 if (em->start > logical || em->start + em->len < logical) {
4974 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, "
4975 "found %Lu-%Lu", logical, em->start,
4976 em->start + em->len);
4977 free_extent_map(em);
4978 return -EINVAL;
4979 }
4980
4981 map = (struct map_lookup *)em->bdev;
4982 offset = logical - em->start;
4983
4984 stripe_len = map->stripe_len;
4985 stripe_nr = offset;
4986 /*
4987 * stripe_nr counts the total number of stripes we have to stride
4988 * to get to this block
4989 */
4990 stripe_nr = div64_u64(stripe_nr, stripe_len);
4991
4992 stripe_offset = stripe_nr * stripe_len;
4993 BUG_ON(offset < stripe_offset);
4994
4995 /* stripe_offset is the offset of this block in its stripe*/
4996 stripe_offset = offset - stripe_offset;
4997
4998 /* if we're here for raid56, we need to know the stripe aligned start */
4999 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5000 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
5001 raid56_full_stripe_start = offset;
5002
5003 /* allow a write of a full stripe, but make sure we don't
5004 * allow straddling of stripes
5005 */
5006 raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
5007 full_stripe_len);
5008 raid56_full_stripe_start *= full_stripe_len;
5009 }
5010
5011 if (rw & REQ_DISCARD) {
5012 /* we don't discard raid56 yet */
5013 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5014 ret = -EOPNOTSUPP;
5015 goto out;
5016 }
5017 *length = min_t(u64, em->len - offset, *length);
5018 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
5019 u64 max_len;
5020 /* For writes to RAID[56], allow a full stripeset across all disks.
5021 For other RAID types and for RAID[56] reads, just allow a single
5022 stripe (on a single disk). */
5023 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
5024 (rw & REQ_WRITE)) {
5025 max_len = stripe_len * nr_data_stripes(map) -
5026 (offset - raid56_full_stripe_start);
5027 } else {
5028 /* we limit the length of each bio to what fits in a stripe */
5029 max_len = stripe_len - stripe_offset;
5030 }
5031 *length = min_t(u64, em->len - offset, max_len);
5032 } else {
5033 *length = em->len - offset;
5034 }
5035
5036 /* This is for when we're called from btrfs_merge_bio_hook() and all
5037 it cares about is the length */
5038 if (!bbio_ret)
5039 goto out;
5040
5041 btrfs_dev_replace_lock(dev_replace);
5042 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
5043 if (!dev_replace_is_ongoing)
5044 btrfs_dev_replace_unlock(dev_replace);
5045
5046 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
5047 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
5048 dev_replace->tgtdev != NULL) {
5049 /*
5050 * in dev-replace case, for repair case (that's the only
5051 * case where the mirror is selected explicitly when
5052 * calling btrfs_map_block), blocks left of the left cursor
5053 * can also be read from the target drive.
5054 * For REQ_GET_READ_MIRRORS, the target drive is added as
5055 * the last one to the array of stripes. For READ, it also
5056 * needs to be supported using the same mirror number.
5057 * If the requested block is not left of the left cursor,
5058 * EIO is returned. This can happen because btrfs_num_copies()
5059 * returns one more in the dev-replace case.
5060 */
5061 u64 tmp_length = *length;
5062 struct btrfs_bio *tmp_bbio = NULL;
5063 int tmp_num_stripes;
5064 u64 srcdev_devid = dev_replace->srcdev->devid;
5065 int index_srcdev = 0;
5066 int found = 0;
5067 u64 physical_of_found = 0;
5068
5069 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
5070 logical, &tmp_length, &tmp_bbio, 0, 0);
5071 if (ret) {
5072 WARN_ON(tmp_bbio != NULL);
5073 goto out;
5074 }
5075
5076 tmp_num_stripes = tmp_bbio->num_stripes;
5077 if (mirror_num > tmp_num_stripes) {
5078 /*
5079 * REQ_GET_READ_MIRRORS does not contain this
5080 * mirror, that means that the requested area
5081 * is not left of the left cursor
5082 */
5083 ret = -EIO;
5084 btrfs_put_bbio(tmp_bbio);
5085 goto out;
5086 }
5087
5088 /*
5089 * process the rest of the function using the mirror_num
5090 * of the source drive. Therefore look it up first.
5091 * At the end, patch the device pointer to the one of the
5092 * target drive.
5093 */
5094 for (i = 0; i < tmp_num_stripes; i++) {
5095 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) {
5096 /*
5097 * In case of DUP, in order to keep it
5098 * simple, only add the mirror with the
5099 * lowest physical address
5100 */
5101 if (found &&
5102 physical_of_found <=
5103 tmp_bbio->stripes[i].physical)
5104 continue;
5105 index_srcdev = i;
5106 found = 1;
5107 physical_of_found =
5108 tmp_bbio->stripes[i].physical;
5109 }
5110 }
5111
5112 if (found) {
5113 mirror_num = index_srcdev + 1;
5114 patch_the_first_stripe_for_dev_replace = 1;
5115 physical_to_patch_in_first_stripe = physical_of_found;
5116 } else {
5117 WARN_ON(1);
5118 ret = -EIO;
5119 btrfs_put_bbio(tmp_bbio);
5120 goto out;
5121 }
5122
5123 btrfs_put_bbio(tmp_bbio);
5124 } else if (mirror_num > map->num_stripes) {
5125 mirror_num = 0;
5126 }
5127
5128 num_stripes = 1;
5129 stripe_index = 0;
5130 stripe_nr_orig = stripe_nr;
5131 stripe_nr_end = ALIGN(offset + *length, map->stripe_len);
5132 stripe_nr_end = div_u64(stripe_nr_end, map->stripe_len);
5133 stripe_end_offset = stripe_nr_end * map->stripe_len -
5134 (offset + *length);
5135
5136 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5137 if (rw & REQ_DISCARD)
5138 num_stripes = min_t(u64, map->num_stripes,
5139 stripe_nr_end - stripe_nr_orig);
5140 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5141 &stripe_index);
5142 if (!(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)))
5143 mirror_num = 1;
5144 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
5145 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
5146 num_stripes = map->num_stripes;
5147 else if (mirror_num)
5148 stripe_index = mirror_num - 1;
5149 else {
5150 stripe_index = find_live_mirror(fs_info, map, 0,
5151 map->num_stripes,
5152 current->pid % map->num_stripes,
5153 dev_replace_is_ongoing);
5154 mirror_num = stripe_index + 1;
5155 }
5156
5157 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
5158 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
5159 num_stripes = map->num_stripes;
5160 } else if (mirror_num) {
5161 stripe_index = mirror_num - 1;
5162 } else {
5163 mirror_num = 1;
5164 }
5165
5166 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5167 u32 factor = map->num_stripes / map->sub_stripes;
5168
5169 stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
5170 stripe_index *= map->sub_stripes;
5171
5172 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5173 num_stripes = map->sub_stripes;
5174 else if (rw & REQ_DISCARD)
5175 num_stripes = min_t(u64, map->sub_stripes *
5176 (stripe_nr_end - stripe_nr_orig),
5177 map->num_stripes);
5178 else if (mirror_num)
5179 stripe_index += mirror_num - 1;
5180 else {
5181 int old_stripe_index = stripe_index;
5182 stripe_index = find_live_mirror(fs_info, map,
5183 stripe_index,
5184 map->sub_stripes, stripe_index +
5185 current->pid % map->sub_stripes,
5186 dev_replace_is_ongoing);
5187 mirror_num = stripe_index - old_stripe_index + 1;
5188 }
5189
5190 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5191 if (need_raid_map &&
5192 ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5193 mirror_num > 1)) {
5194 /* push stripe_nr back to the start of the full stripe */
5195 stripe_nr = div_u64(raid56_full_stripe_start,
5196 stripe_len * nr_data_stripes(map));
5197
5198 /* RAID[56] write or recovery. Return all stripes */
5199 num_stripes = map->num_stripes;
5200 max_errors = nr_parity_stripes(map);
5201
5202 *length = map->stripe_len;
5203 stripe_index = 0;
5204 stripe_offset = 0;
5205 } else {
5206 /*
5207 * Mirror #0 or #1 means the original data block.
5208 * Mirror #2 is RAID5 parity block.
5209 * Mirror #3 is RAID6 Q block.
5210 */
5211 stripe_nr = div_u64_rem(stripe_nr,
5212 nr_data_stripes(map), &stripe_index);
5213 if (mirror_num > 1)
5214 stripe_index = nr_data_stripes(map) +
5215 mirror_num - 2;
5216
5217 /* We distribute the parity blocks across stripes */
5218 div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
5219 &stripe_index);
5220 if (!(rw & (REQ_WRITE | REQ_DISCARD |
5221 REQ_GET_READ_MIRRORS)) && mirror_num <= 1)
5222 mirror_num = 1;
5223 }
5224 } else {
5225 /*
5226 * after this, stripe_nr is the number of stripes on this
5227 * device we have to walk to find the data, and stripe_index is
5228 * the number of our device in the stripe array
5229 */
5230 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5231 &stripe_index);
5232 mirror_num = stripe_index + 1;
5233 }
5234 BUG_ON(stripe_index >= map->num_stripes);
5235
5236 num_alloc_stripes = num_stripes;
5237 if (dev_replace_is_ongoing) {
5238 if (rw & (REQ_WRITE | REQ_DISCARD))
5239 num_alloc_stripes <<= 1;
5240 if (rw & REQ_GET_READ_MIRRORS)
5241 num_alloc_stripes++;
5242 tgtdev_indexes = num_stripes;
5243 }
5244
5245 bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes);
5246 if (!bbio) {
5247 ret = -ENOMEM;
5248 goto out;
5249 }
5250 if (dev_replace_is_ongoing)
5251 bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes);
5252
5253 /* build raid_map */
5254 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
5255 need_raid_map && ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5256 mirror_num > 1)) {
5257 u64 tmp;
5258 unsigned rot;
5259
5260 bbio->raid_map = (u64 *)((void *)bbio->stripes +
5261 sizeof(struct btrfs_bio_stripe) *
5262 num_alloc_stripes +
5263 sizeof(int) * tgtdev_indexes);
5264
5265 /* Work out the disk rotation on this stripe-set */
5266 div_u64_rem(stripe_nr, num_stripes, &rot);
5267
5268 /* Fill in the logical address of each stripe */
5269 tmp = stripe_nr * nr_data_stripes(map);
5270 for (i = 0; i < nr_data_stripes(map); i++)
5271 bbio->raid_map[(i+rot) % num_stripes] =
5272 em->start + (tmp + i) * map->stripe_len;
5273
5274 bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
5275 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5276 bbio->raid_map[(i+rot+1) % num_stripes] =
5277 RAID6_Q_STRIPE;
5278 }
5279
5280 if (rw & REQ_DISCARD) {
5281 u32 factor = 0;
5282 u32 sub_stripes = 0;
5283 u64 stripes_per_dev = 0;
5284 u32 remaining_stripes = 0;
5285 u32 last_stripe = 0;
5286
5287 if (map->type &
5288 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
5289 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5290 sub_stripes = 1;
5291 else
5292 sub_stripes = map->sub_stripes;
5293
5294 factor = map->num_stripes / sub_stripes;
5295 stripes_per_dev = div_u64_rem(stripe_nr_end -
5296 stripe_nr_orig,
5297 factor,
5298 &remaining_stripes);
5299 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
5300 last_stripe *= sub_stripes;
5301 }
5302
5303 for (i = 0; i < num_stripes; i++) {
5304 bbio->stripes[i].physical =
5305 map->stripes[stripe_index].physical +
5306 stripe_offset + stripe_nr * map->stripe_len;
5307 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
5308
5309 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
5310 BTRFS_BLOCK_GROUP_RAID10)) {
5311 bbio->stripes[i].length = stripes_per_dev *
5312 map->stripe_len;
5313
5314 if (i / sub_stripes < remaining_stripes)
5315 bbio->stripes[i].length +=
5316 map->stripe_len;
5317
5318 /*
5319 * Special for the first stripe and
5320 * the last stripe:
5321 *
5322 * |-------|...|-------|
5323 * |----------|
5324 * off end_off
5325 */
5326 if (i < sub_stripes)
5327 bbio->stripes[i].length -=
5328 stripe_offset;
5329
5330 if (stripe_index >= last_stripe &&
5331 stripe_index <= (last_stripe +
5332 sub_stripes - 1))
5333 bbio->stripes[i].length -=
5334 stripe_end_offset;
5335
5336 if (i == sub_stripes - 1)
5337 stripe_offset = 0;
5338 } else
5339 bbio->stripes[i].length = *length;
5340
5341 stripe_index++;
5342 if (stripe_index == map->num_stripes) {
5343 /* This could only happen for RAID0/10 */
5344 stripe_index = 0;
5345 stripe_nr++;
5346 }
5347 }
5348 } else {
5349 for (i = 0; i < num_stripes; i++) {
5350 bbio->stripes[i].physical =
5351 map->stripes[stripe_index].physical +
5352 stripe_offset +
5353 stripe_nr * map->stripe_len;
5354 bbio->stripes[i].dev =
5355 map->stripes[stripe_index].dev;
5356 stripe_index++;
5357 }
5358 }
5359
5360 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5361 max_errors = btrfs_chunk_max_errors(map);
5362
5363 if (bbio->raid_map)
5364 sort_parity_stripes(bbio, num_stripes);
5365
5366 tgtdev_indexes = 0;
5367 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
5368 dev_replace->tgtdev != NULL) {
5369 int index_where_to_add;
5370 u64 srcdev_devid = dev_replace->srcdev->devid;
5371
5372 /*
5373 * duplicate the write operations while the dev replace
5374 * procedure is running. Since the copying of the old disk
5375 * to the new disk takes place at run time while the
5376 * filesystem is mounted writable, the regular write
5377 * operations to the old disk have to be duplicated to go
5378 * to the new disk as well.
5379 * Note that device->missing is handled by the caller, and
5380 * that the write to the old disk is already set up in the
5381 * stripes array.
5382 */
5383 index_where_to_add = num_stripes;
5384 for (i = 0; i < num_stripes; i++) {
5385 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5386 /* write to new disk, too */
5387 struct btrfs_bio_stripe *new =
5388 bbio->stripes + index_where_to_add;
5389 struct btrfs_bio_stripe *old =
5390 bbio->stripes + i;
5391
5392 new->physical = old->physical;
5393 new->length = old->length;
5394 new->dev = dev_replace->tgtdev;
5395 bbio->tgtdev_map[i] = index_where_to_add;
5396 index_where_to_add++;
5397 max_errors++;
5398 tgtdev_indexes++;
5399 }
5400 }
5401 num_stripes = index_where_to_add;
5402 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
5403 dev_replace->tgtdev != NULL) {
5404 u64 srcdev_devid = dev_replace->srcdev->devid;
5405 int index_srcdev = 0;
5406 int found = 0;
5407 u64 physical_of_found = 0;
5408
5409 /*
5410 * During the dev-replace procedure, the target drive can
5411 * also be used to read data in case it is needed to repair
5412 * a corrupt block elsewhere. This is possible if the
5413 * requested area is left of the left cursor. In this area,
5414 * the target drive is a full copy of the source drive.
5415 */
5416 for (i = 0; i < num_stripes; i++) {
5417 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5418 /*
5419 * In case of DUP, in order to keep it
5420 * simple, only add the mirror with the
5421 * lowest physical address
5422 */
5423 if (found &&
5424 physical_of_found <=
5425 bbio->stripes[i].physical)
5426 continue;
5427 index_srcdev = i;
5428 found = 1;
5429 physical_of_found = bbio->stripes[i].physical;
5430 }
5431 }
5432 if (found) {
5433 if (physical_of_found + map->stripe_len <=
5434 dev_replace->cursor_left) {
5435 struct btrfs_bio_stripe *tgtdev_stripe =
5436 bbio->stripes + num_stripes;
5437
5438 tgtdev_stripe->physical = physical_of_found;
5439 tgtdev_stripe->length =
5440 bbio->stripes[index_srcdev].length;
5441 tgtdev_stripe->dev = dev_replace->tgtdev;
5442 bbio->tgtdev_map[index_srcdev] = num_stripes;
5443
5444 tgtdev_indexes++;
5445 num_stripes++;
5446 }
5447 }
5448 }
5449
5450 *bbio_ret = bbio;
5451 bbio->map_type = map->type;
5452 bbio->num_stripes = num_stripes;
5453 bbio->max_errors = max_errors;
5454 bbio->mirror_num = mirror_num;
5455 bbio->num_tgtdevs = tgtdev_indexes;
5456
5457 /*
5458 * this is the case that REQ_READ && dev_replace_is_ongoing &&
5459 * mirror_num == num_stripes + 1 && dev_replace target drive is
5460 * available as a mirror
5461 */
5462 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
5463 WARN_ON(num_stripes > 1);
5464 bbio->stripes[0].dev = dev_replace->tgtdev;
5465 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
5466 bbio->mirror_num = map->num_stripes + 1;
5467 }
5468 out:
5469 if (dev_replace_is_ongoing)
5470 btrfs_dev_replace_unlock(dev_replace);
5471 free_extent_map(em);
5472 return ret;
5473 }
5474
5475 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5476 u64 logical, u64 *length,
5477 struct btrfs_bio **bbio_ret, int mirror_num)
5478 {
5479 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5480 mirror_num, 0);
5481 }
5482
5483 /* For Scrub/replace */
5484 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
5485 u64 logical, u64 *length,
5486 struct btrfs_bio **bbio_ret, int mirror_num,
5487 int need_raid_map)
5488 {
5489 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5490 mirror_num, need_raid_map);
5491 }
5492
5493 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
5494 u64 chunk_start, u64 physical, u64 devid,
5495 u64 **logical, int *naddrs, int *stripe_len)
5496 {
5497 struct extent_map_tree *em_tree = &map_tree->map_tree;
5498 struct extent_map *em;
5499 struct map_lookup *map;
5500 u64 *buf;
5501 u64 bytenr;
5502 u64 length;
5503 u64 stripe_nr;
5504 u64 rmap_len;
5505 int i, j, nr = 0;
5506
5507 read_lock(&em_tree->lock);
5508 em = lookup_extent_mapping(em_tree, chunk_start, 1);
5509 read_unlock(&em_tree->lock);
5510
5511 if (!em) {
5512 printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
5513 chunk_start);
5514 return -EIO;
5515 }
5516
5517 if (em->start != chunk_start) {
5518 printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
5519 em->start, chunk_start);
5520 free_extent_map(em);
5521 return -EIO;
5522 }
5523 map = (struct map_lookup *)em->bdev;
5524
5525 length = em->len;
5526 rmap_len = map->stripe_len;
5527
5528 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5529 length = div_u64(length, map->num_stripes / map->sub_stripes);
5530 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5531 length = div_u64(length, map->num_stripes);
5532 else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5533 length = div_u64(length, nr_data_stripes(map));
5534 rmap_len = map->stripe_len * nr_data_stripes(map);
5535 }
5536
5537 buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
5538 BUG_ON(!buf); /* -ENOMEM */
5539
5540 for (i = 0; i < map->num_stripes; i++) {
5541 if (devid && map->stripes[i].dev->devid != devid)
5542 continue;
5543 if (map->stripes[i].physical > physical ||
5544 map->stripes[i].physical + length <= physical)
5545 continue;
5546
5547 stripe_nr = physical - map->stripes[i].physical;
5548 stripe_nr = div_u64(stripe_nr, map->stripe_len);
5549
5550 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5551 stripe_nr = stripe_nr * map->num_stripes + i;
5552 stripe_nr = div_u64(stripe_nr, map->sub_stripes);
5553 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5554 stripe_nr = stripe_nr * map->num_stripes + i;
5555 } /* else if RAID[56], multiply by nr_data_stripes().
5556 * Alternatively, just use rmap_len below instead of
5557 * map->stripe_len */
5558
5559 bytenr = chunk_start + stripe_nr * rmap_len;
5560 WARN_ON(nr >= map->num_stripes);
5561 for (j = 0; j < nr; j++) {
5562 if (buf[j] == bytenr)
5563 break;
5564 }
5565 if (j == nr) {
5566 WARN_ON(nr >= map->num_stripes);
5567 buf[nr++] = bytenr;
5568 }
5569 }
5570
5571 *logical = buf;
5572 *naddrs = nr;
5573 *stripe_len = rmap_len;
5574
5575 free_extent_map(em);
5576 return 0;
5577 }
5578
5579 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio, int err)
5580 {
5581 if (likely(bbio->flags & BTRFS_BIO_ORIG_BIO_SUBMITTED))
5582 bio_endio_nodec(bio, err);
5583 else
5584 bio_endio(bio, err);
5585 btrfs_put_bbio(bbio);
5586 }
5587
5588 static void btrfs_end_bio(struct bio *bio, int err)
5589 {
5590 struct btrfs_bio *bbio = bio->bi_private;
5591 struct btrfs_device *dev = bbio->stripes[0].dev;
5592 int is_orig_bio = 0;
5593
5594 if (err) {
5595 atomic_inc(&bbio->error);
5596 if (err == -EIO || err == -EREMOTEIO) {
5597 unsigned int stripe_index =
5598 btrfs_io_bio(bio)->stripe_index;
5599
5600 BUG_ON(stripe_index >= bbio->num_stripes);
5601 dev = bbio->stripes[stripe_index].dev;
5602 if (dev->bdev) {
5603 if (bio->bi_rw & WRITE)
5604 btrfs_dev_stat_inc(dev,
5605 BTRFS_DEV_STAT_WRITE_ERRS);
5606 else
5607 btrfs_dev_stat_inc(dev,
5608 BTRFS_DEV_STAT_READ_ERRS);
5609 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
5610 btrfs_dev_stat_inc(dev,
5611 BTRFS_DEV_STAT_FLUSH_ERRS);
5612 btrfs_dev_stat_print_on_error(dev);
5613 }
5614 }
5615 }
5616
5617 if (bio == bbio->orig_bio)
5618 is_orig_bio = 1;
5619
5620 btrfs_bio_counter_dec(bbio->fs_info);
5621
5622 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5623 if (!is_orig_bio) {
5624 bio_put(bio);
5625 bio = bbio->orig_bio;
5626 }
5627
5628 bio->bi_private = bbio->private;
5629 bio->bi_end_io = bbio->end_io;
5630 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5631 /* only send an error to the higher layers if it is
5632 * beyond the tolerance of the btrfs bio
5633 */
5634 if (atomic_read(&bbio->error) > bbio->max_errors) {
5635 err = -EIO;
5636 } else {
5637 /*
5638 * this bio is actually up to date, we didn't
5639 * go over the max number of errors
5640 */
5641 set_bit(BIO_UPTODATE, &bio->bi_flags);
5642 err = 0;
5643 }
5644
5645 btrfs_end_bbio(bbio, bio, err);
5646 } else if (!is_orig_bio) {
5647 bio_put(bio);
5648 }
5649 }
5650
5651 /*
5652 * see run_scheduled_bios for a description of why bios are collected for
5653 * async submit.
5654 *
5655 * This will add one bio to the pending list for a device and make sure
5656 * the work struct is scheduled.
5657 */
5658 static noinline void btrfs_schedule_bio(struct btrfs_root *root,
5659 struct btrfs_device *device,
5660 int rw, struct bio *bio)
5661 {
5662 int should_queue = 1;
5663 struct btrfs_pending_bios *pending_bios;
5664
5665 if (device->missing || !device->bdev) {
5666 bio_endio(bio, -EIO);
5667 return;
5668 }
5669
5670 /* don't bother with additional async steps for reads, right now */
5671 if (!(rw & REQ_WRITE)) {
5672 bio_get(bio);
5673 btrfsic_submit_bio(rw, bio);
5674 bio_put(bio);
5675 return;
5676 }
5677
5678 /*
5679 * nr_async_bios allows us to reliably return congestion to the
5680 * higher layers. Otherwise, the async bio makes it appear we have
5681 * made progress against dirty pages when we've really just put it
5682 * on a queue for later
5683 */
5684 atomic_inc(&root->fs_info->nr_async_bios);
5685 WARN_ON(bio->bi_next);
5686 bio->bi_next = NULL;
5687 bio->bi_rw |= rw;
5688
5689 spin_lock(&device->io_lock);
5690 if (bio->bi_rw & REQ_SYNC)
5691 pending_bios = &device->pending_sync_bios;
5692 else
5693 pending_bios = &device->pending_bios;
5694
5695 if (pending_bios->tail)
5696 pending_bios->tail->bi_next = bio;
5697
5698 pending_bios->tail = bio;
5699 if (!pending_bios->head)
5700 pending_bios->head = bio;
5701 if (device->running_pending)
5702 should_queue = 0;
5703
5704 spin_unlock(&device->io_lock);
5705
5706 if (should_queue)
5707 btrfs_queue_work(root->fs_info->submit_workers,
5708 &device->work);
5709 }
5710
5711 static int bio_size_ok(struct block_device *bdev, struct bio *bio,
5712 sector_t sector)
5713 {
5714 struct bio_vec *prev;
5715 struct request_queue *q = bdev_get_queue(bdev);
5716 unsigned int max_sectors = queue_max_sectors(q);
5717 struct bvec_merge_data bvm = {
5718 .bi_bdev = bdev,
5719 .bi_sector = sector,
5720 .bi_rw = bio->bi_rw,
5721 };
5722
5723 if (WARN_ON(bio->bi_vcnt == 0))
5724 return 1;
5725
5726 prev = &bio->bi_io_vec[bio->bi_vcnt - 1];
5727 if (bio_sectors(bio) > max_sectors)
5728 return 0;
5729
5730 if (!q->merge_bvec_fn)
5731 return 1;
5732
5733 bvm.bi_size = bio->bi_iter.bi_size - prev->bv_len;
5734 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len)
5735 return 0;
5736 return 1;
5737 }
5738
5739 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5740 struct bio *bio, u64 physical, int dev_nr,
5741 int rw, int async)
5742 {
5743 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
5744
5745 bio->bi_private = bbio;
5746 btrfs_io_bio(bio)->stripe_index = dev_nr;
5747 bio->bi_end_io = btrfs_end_bio;
5748 bio->bi_iter.bi_sector = physical >> 9;
5749 #ifdef DEBUG
5750 {
5751 struct rcu_string *name;
5752
5753 rcu_read_lock();
5754 name = rcu_dereference(dev->name);
5755 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
5756 "(%s id %llu), size=%u\n", rw,
5757 (u64)bio->bi_iter.bi_sector, (u_long)dev->bdev->bd_dev,
5758 name->str, dev->devid, bio->bi_iter.bi_size);
5759 rcu_read_unlock();
5760 }
5761 #endif
5762 bio->bi_bdev = dev->bdev;
5763
5764 btrfs_bio_counter_inc_noblocked(root->fs_info);
5765
5766 if (async)
5767 btrfs_schedule_bio(root, dev, rw, bio);
5768 else
5769 btrfsic_submit_bio(rw, bio);
5770 }
5771
5772 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5773 struct bio *first_bio, struct btrfs_device *dev,
5774 int dev_nr, int rw, int async)
5775 {
5776 struct bio_vec *bvec = first_bio->bi_io_vec;
5777 struct bio *bio;
5778 int nr_vecs = bio_get_nr_vecs(dev->bdev);
5779 u64 physical = bbio->stripes[dev_nr].physical;
5780
5781 again:
5782 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS);
5783 if (!bio)
5784 return -ENOMEM;
5785
5786 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) {
5787 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5788 bvec->bv_offset) < bvec->bv_len) {
5789 u64 len = bio->bi_iter.bi_size;
5790
5791 atomic_inc(&bbio->stripes_pending);
5792 submit_stripe_bio(root, bbio, bio, physical, dev_nr,
5793 rw, async);
5794 physical += len;
5795 goto again;
5796 }
5797 bvec++;
5798 }
5799
5800 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async);
5801 return 0;
5802 }
5803
5804 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
5805 {
5806 atomic_inc(&bbio->error);
5807 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5808 /* Shoud be the original bio. */
5809 WARN_ON(bio != bbio->orig_bio);
5810
5811 bio->bi_private = bbio->private;
5812 bio->bi_end_io = bbio->end_io;
5813 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5814 bio->bi_iter.bi_sector = logical >> 9;
5815
5816 btrfs_end_bbio(bbio, bio, -EIO);
5817 }
5818 }
5819
5820 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
5821 int mirror_num, int async_submit)
5822 {
5823 struct btrfs_device *dev;
5824 struct bio *first_bio = bio;
5825 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
5826 u64 length = 0;
5827 u64 map_length;
5828 int ret;
5829 int dev_nr;
5830 int total_devs;
5831 struct btrfs_bio *bbio = NULL;
5832
5833 length = bio->bi_iter.bi_size;
5834 map_length = length;
5835
5836 btrfs_bio_counter_inc_blocked(root->fs_info);
5837 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
5838 mirror_num, 1);
5839 if (ret) {
5840 btrfs_bio_counter_dec(root->fs_info);
5841 return ret;
5842 }
5843
5844 total_devs = bbio->num_stripes;
5845 bbio->orig_bio = first_bio;
5846 bbio->private = first_bio->bi_private;
5847 bbio->end_io = first_bio->bi_end_io;
5848 bbio->fs_info = root->fs_info;
5849 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
5850
5851 if (bbio->raid_map) {
5852 /* In this case, map_length has been set to the length of
5853 a single stripe; not the whole write */
5854 if (rw & WRITE) {
5855 ret = raid56_parity_write(root, bio, bbio, map_length);
5856 } else {
5857 ret = raid56_parity_recover(root, bio, bbio, map_length,
5858 mirror_num, 1);
5859 }
5860
5861 btrfs_bio_counter_dec(root->fs_info);
5862 return ret;
5863 }
5864
5865 if (map_length < length) {
5866 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
5867 logical, length, map_length);
5868 BUG();
5869 }
5870
5871 for (dev_nr = 0; dev_nr < total_devs; dev_nr++) {
5872 dev = bbio->stripes[dev_nr].dev;
5873 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
5874 bbio_error(bbio, first_bio, logical);
5875 continue;
5876 }
5877
5878 /*
5879 * Check and see if we're ok with this bio based on it's size
5880 * and offset with the given device.
5881 */
5882 if (!bio_size_ok(dev->bdev, first_bio,
5883 bbio->stripes[dev_nr].physical >> 9)) {
5884 ret = breakup_stripe_bio(root, bbio, first_bio, dev,
5885 dev_nr, rw, async_submit);
5886 BUG_ON(ret);
5887 continue;
5888 }
5889
5890 if (dev_nr < total_devs - 1) {
5891 bio = btrfs_bio_clone(first_bio, GFP_NOFS);
5892 BUG_ON(!bio); /* -ENOMEM */
5893 } else {
5894 bio = first_bio;
5895 bbio->flags |= BTRFS_BIO_ORIG_BIO_SUBMITTED;
5896 }
5897
5898 submit_stripe_bio(root, bbio, bio,
5899 bbio->stripes[dev_nr].physical, dev_nr, rw,
5900 async_submit);
5901 }
5902 btrfs_bio_counter_dec(root->fs_info);
5903 return 0;
5904 }
5905
5906 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
5907 u8 *uuid, u8 *fsid)
5908 {
5909 struct btrfs_device *device;
5910 struct btrfs_fs_devices *cur_devices;
5911
5912 cur_devices = fs_info->fs_devices;
5913 while (cur_devices) {
5914 if (!fsid ||
5915 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
5916 device = __find_device(&cur_devices->devices,
5917 devid, uuid);
5918 if (device)
5919 return device;
5920 }
5921 cur_devices = cur_devices->seed;
5922 }
5923 return NULL;
5924 }
5925
5926 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
5927 struct btrfs_fs_devices *fs_devices,
5928 u64 devid, u8 *dev_uuid)
5929 {
5930 struct btrfs_device *device;
5931
5932 device = btrfs_alloc_device(NULL, &devid, dev_uuid);
5933 if (IS_ERR(device))
5934 return NULL;
5935
5936 list_add(&device->dev_list, &fs_devices->devices);
5937 device->fs_devices = fs_devices;
5938 fs_devices->num_devices++;
5939
5940 device->missing = 1;
5941 fs_devices->missing_devices++;
5942
5943 return device;
5944 }
5945
5946 /**
5947 * btrfs_alloc_device - allocate struct btrfs_device
5948 * @fs_info: used only for generating a new devid, can be NULL if
5949 * devid is provided (i.e. @devid != NULL).
5950 * @devid: a pointer to devid for this device. If NULL a new devid
5951 * is generated.
5952 * @uuid: a pointer to UUID for this device. If NULL a new UUID
5953 * is generated.
5954 *
5955 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
5956 * on error. Returned struct is not linked onto any lists and can be
5957 * destroyed with kfree() right away.
5958 */
5959 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
5960 const u64 *devid,
5961 const u8 *uuid)
5962 {
5963 struct btrfs_device *dev;
5964 u64 tmp;
5965
5966 if (WARN_ON(!devid && !fs_info))
5967 return ERR_PTR(-EINVAL);
5968
5969 dev = __alloc_device();
5970 if (IS_ERR(dev))
5971 return dev;
5972
5973 if (devid)
5974 tmp = *devid;
5975 else {
5976 int ret;
5977
5978 ret = find_next_devid(fs_info, &tmp);
5979 if (ret) {
5980 kfree(dev);
5981 return ERR_PTR(ret);
5982 }
5983 }
5984 dev->devid = tmp;
5985
5986 if (uuid)
5987 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
5988 else
5989 generate_random_uuid(dev->uuid);
5990
5991 btrfs_init_work(&dev->work, btrfs_submit_helper,
5992 pending_bios_fn, NULL, NULL);
5993
5994 return dev;
5995 }
5996
5997 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
5998 struct extent_buffer *leaf,
5999 struct btrfs_chunk *chunk)
6000 {
6001 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
6002 struct map_lookup *map;
6003 struct extent_map *em;
6004 u64 logical;
6005 u64 length;
6006 u64 devid;
6007 u8 uuid[BTRFS_UUID_SIZE];
6008 int num_stripes;
6009 int ret;
6010 int i;
6011
6012 logical = key->offset;
6013 length = btrfs_chunk_length(leaf, chunk);
6014
6015 read_lock(&map_tree->map_tree.lock);
6016 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
6017 read_unlock(&map_tree->map_tree.lock);
6018
6019 /* already mapped? */
6020 if (em && em->start <= logical && em->start + em->len > logical) {
6021 free_extent_map(em);
6022 return 0;
6023 } else if (em) {
6024 free_extent_map(em);
6025 }
6026
6027 em = alloc_extent_map();
6028 if (!em)
6029 return -ENOMEM;
6030 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
6031 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
6032 if (!map) {
6033 free_extent_map(em);
6034 return -ENOMEM;
6035 }
6036
6037 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
6038 em->bdev = (struct block_device *)map;
6039 em->start = logical;
6040 em->len = length;
6041 em->orig_start = 0;
6042 em->block_start = 0;
6043 em->block_len = em->len;
6044
6045 map->num_stripes = num_stripes;
6046 map->io_width = btrfs_chunk_io_width(leaf, chunk);
6047 map->io_align = btrfs_chunk_io_align(leaf, chunk);
6048 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
6049 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6050 map->type = btrfs_chunk_type(leaf, chunk);
6051 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
6052 for (i = 0; i < num_stripes; i++) {
6053 map->stripes[i].physical =
6054 btrfs_stripe_offset_nr(leaf, chunk, i);
6055 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
6056 read_extent_buffer(leaf, uuid, (unsigned long)
6057 btrfs_stripe_dev_uuid_nr(chunk, i),
6058 BTRFS_UUID_SIZE);
6059 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
6060 uuid, NULL);
6061 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
6062 free_extent_map(em);
6063 return -EIO;
6064 }
6065 if (!map->stripes[i].dev) {
6066 map->stripes[i].dev =
6067 add_missing_dev(root, root->fs_info->fs_devices,
6068 devid, uuid);
6069 if (!map->stripes[i].dev) {
6070 free_extent_map(em);
6071 return -EIO;
6072 }
6073 }
6074 map->stripes[i].dev->in_fs_metadata = 1;
6075 }
6076
6077 write_lock(&map_tree->map_tree.lock);
6078 ret = add_extent_mapping(&map_tree->map_tree, em, 0);
6079 write_unlock(&map_tree->map_tree.lock);
6080 BUG_ON(ret); /* Tree corruption */
6081 free_extent_map(em);
6082
6083 return 0;
6084 }
6085
6086 static void fill_device_from_item(struct extent_buffer *leaf,
6087 struct btrfs_dev_item *dev_item,
6088 struct btrfs_device *device)
6089 {
6090 unsigned long ptr;
6091
6092 device->devid = btrfs_device_id(leaf, dev_item);
6093 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
6094 device->total_bytes = device->disk_total_bytes;
6095 device->commit_total_bytes = device->disk_total_bytes;
6096 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
6097 device->commit_bytes_used = device->bytes_used;
6098 device->type = btrfs_device_type(leaf, dev_item);
6099 device->io_align = btrfs_device_io_align(leaf, dev_item);
6100 device->io_width = btrfs_device_io_width(leaf, dev_item);
6101 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
6102 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
6103 device->is_tgtdev_for_dev_replace = 0;
6104
6105 ptr = btrfs_device_uuid(dev_item);
6106 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
6107 }
6108
6109 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_root *root,
6110 u8 *fsid)
6111 {
6112 struct btrfs_fs_devices *fs_devices;
6113 int ret;
6114
6115 BUG_ON(!mutex_is_locked(&uuid_mutex));
6116
6117 fs_devices = root->fs_info->fs_devices->seed;
6118 while (fs_devices) {
6119 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE))
6120 return fs_devices;
6121
6122 fs_devices = fs_devices->seed;
6123 }
6124
6125 fs_devices = find_fsid(fsid);
6126 if (!fs_devices) {
6127 if (!btrfs_test_opt(root, DEGRADED))
6128 return ERR_PTR(-ENOENT);
6129
6130 fs_devices = alloc_fs_devices(fsid);
6131 if (IS_ERR(fs_devices))
6132 return fs_devices;
6133
6134 fs_devices->seeding = 1;
6135 fs_devices->opened = 1;
6136 return fs_devices;
6137 }
6138
6139 fs_devices = clone_fs_devices(fs_devices);
6140 if (IS_ERR(fs_devices))
6141 return fs_devices;
6142
6143 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
6144 root->fs_info->bdev_holder);
6145 if (ret) {
6146 free_fs_devices(fs_devices);
6147 fs_devices = ERR_PTR(ret);
6148 goto out;
6149 }
6150
6151 if (!fs_devices->seeding) {
6152 __btrfs_close_devices(fs_devices);
6153 free_fs_devices(fs_devices);
6154 fs_devices = ERR_PTR(-EINVAL);
6155 goto out;
6156 }
6157
6158 fs_devices->seed = root->fs_info->fs_devices->seed;
6159 root->fs_info->fs_devices->seed = fs_devices;
6160 out:
6161 return fs_devices;
6162 }
6163
6164 static int read_one_dev(struct btrfs_root *root,
6165 struct extent_buffer *leaf,
6166 struct btrfs_dev_item *dev_item)
6167 {
6168 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6169 struct btrfs_device *device;
6170 u64 devid;
6171 int ret;
6172 u8 fs_uuid[BTRFS_UUID_SIZE];
6173 u8 dev_uuid[BTRFS_UUID_SIZE];
6174
6175 devid = btrfs_device_id(leaf, dev_item);
6176 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
6177 BTRFS_UUID_SIZE);
6178 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
6179 BTRFS_UUID_SIZE);
6180
6181 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
6182 fs_devices = open_seed_devices(root, fs_uuid);
6183 if (IS_ERR(fs_devices))
6184 return PTR_ERR(fs_devices);
6185 }
6186
6187 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
6188 if (!device) {
6189 if (!btrfs_test_opt(root, DEGRADED))
6190 return -EIO;
6191
6192 btrfs_warn(root->fs_info, "devid %llu missing", devid);
6193 device = add_missing_dev(root, fs_devices, devid, dev_uuid);
6194 if (!device)
6195 return -ENOMEM;
6196 } else {
6197 if (!device->bdev && !btrfs_test_opt(root, DEGRADED))
6198 return -EIO;
6199
6200 if(!device->bdev && !device->missing) {
6201 /*
6202 * this happens when a device that was properly setup
6203 * in the device info lists suddenly goes bad.
6204 * device->bdev is NULL, and so we have to set
6205 * device->missing to one here
6206 */
6207 device->fs_devices->missing_devices++;
6208 device->missing = 1;
6209 }
6210
6211 /* Move the device to its own fs_devices */
6212 if (device->fs_devices != fs_devices) {
6213 ASSERT(device->missing);
6214
6215 list_move(&device->dev_list, &fs_devices->devices);
6216 device->fs_devices->num_devices--;
6217 fs_devices->num_devices++;
6218
6219 device->fs_devices->missing_devices--;
6220 fs_devices->missing_devices++;
6221
6222 device->fs_devices = fs_devices;
6223 }
6224 }
6225
6226 if (device->fs_devices != root->fs_info->fs_devices) {
6227 BUG_ON(device->writeable);
6228 if (device->generation !=
6229 btrfs_device_generation(leaf, dev_item))
6230 return -EINVAL;
6231 }
6232
6233 fill_device_from_item(leaf, dev_item, device);
6234 device->in_fs_metadata = 1;
6235 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
6236 device->fs_devices->total_rw_bytes += device->total_bytes;
6237 spin_lock(&root->fs_info->free_chunk_lock);
6238 root->fs_info->free_chunk_space += device->total_bytes -
6239 device->bytes_used;
6240 spin_unlock(&root->fs_info->free_chunk_lock);
6241 }
6242 ret = 0;
6243 return ret;
6244 }
6245
6246 int btrfs_read_sys_array(struct btrfs_root *root)
6247 {
6248 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
6249 struct extent_buffer *sb;
6250 struct btrfs_disk_key *disk_key;
6251 struct btrfs_chunk *chunk;
6252 u8 *array_ptr;
6253 unsigned long sb_array_offset;
6254 int ret = 0;
6255 u32 num_stripes;
6256 u32 array_size;
6257 u32 len = 0;
6258 u32 cur_offset;
6259 struct btrfs_key key;
6260
6261 ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
6262 /*
6263 * This will create extent buffer of nodesize, superblock size is
6264 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
6265 * overallocate but we can keep it as-is, only the first page is used.
6266 */
6267 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
6268 if (!sb)
6269 return -ENOMEM;
6270 btrfs_set_buffer_uptodate(sb);
6271 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
6272 /*
6273 * The sb extent buffer is artifical and just used to read the system array.
6274 * btrfs_set_buffer_uptodate() call does not properly mark all it's
6275 * pages up-to-date when the page is larger: extent does not cover the
6276 * whole page and consequently check_page_uptodate does not find all
6277 * the page's extents up-to-date (the hole beyond sb),
6278 * write_extent_buffer then triggers a WARN_ON.
6279 *
6280 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
6281 * but sb spans only this function. Add an explicit SetPageUptodate call
6282 * to silence the warning eg. on PowerPC 64.
6283 */
6284 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
6285 SetPageUptodate(sb->pages[0]);
6286
6287 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
6288 array_size = btrfs_super_sys_array_size(super_copy);
6289
6290 array_ptr = super_copy->sys_chunk_array;
6291 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
6292 cur_offset = 0;
6293
6294 while (cur_offset < array_size) {
6295 disk_key = (struct btrfs_disk_key *)array_ptr;
6296 len = sizeof(*disk_key);
6297 if (cur_offset + len > array_size)
6298 goto out_short_read;
6299
6300 btrfs_disk_key_to_cpu(&key, disk_key);
6301
6302 array_ptr += len;
6303 sb_array_offset += len;
6304 cur_offset += len;
6305
6306 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6307 chunk = (struct btrfs_chunk *)sb_array_offset;
6308 /*
6309 * At least one btrfs_chunk with one stripe must be
6310 * present, exact stripe count check comes afterwards
6311 */
6312 len = btrfs_chunk_item_size(1);
6313 if (cur_offset + len > array_size)
6314 goto out_short_read;
6315
6316 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
6317 len = btrfs_chunk_item_size(num_stripes);
6318 if (cur_offset + len > array_size)
6319 goto out_short_read;
6320
6321 ret = read_one_chunk(root, &key, sb, chunk);
6322 if (ret)
6323 break;
6324 } else {
6325 ret = -EIO;
6326 break;
6327 }
6328 array_ptr += len;
6329 sb_array_offset += len;
6330 cur_offset += len;
6331 }
6332 free_extent_buffer(sb);
6333 return ret;
6334
6335 out_short_read:
6336 printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
6337 len, cur_offset);
6338 free_extent_buffer(sb);
6339 return -EIO;
6340 }
6341
6342 int btrfs_read_chunk_tree(struct btrfs_root *root)
6343 {
6344 struct btrfs_path *path;
6345 struct extent_buffer *leaf;
6346 struct btrfs_key key;
6347 struct btrfs_key found_key;
6348 int ret;
6349 int slot;
6350
6351 root = root->fs_info->chunk_root;
6352
6353 path = btrfs_alloc_path();
6354 if (!path)
6355 return -ENOMEM;
6356
6357 mutex_lock(&uuid_mutex);
6358 lock_chunks(root);
6359
6360 /*
6361 * Read all device items, and then all the chunk items. All
6362 * device items are found before any chunk item (their object id
6363 * is smaller than the lowest possible object id for a chunk
6364 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
6365 */
6366 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
6367 key.offset = 0;
6368 key.type = 0;
6369 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6370 if (ret < 0)
6371 goto error;
6372 while (1) {
6373 leaf = path->nodes[0];
6374 slot = path->slots[0];
6375 if (slot >= btrfs_header_nritems(leaf)) {
6376 ret = btrfs_next_leaf(root, path);
6377 if (ret == 0)
6378 continue;
6379 if (ret < 0)
6380 goto error;
6381 break;
6382 }
6383 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6384 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
6385 struct btrfs_dev_item *dev_item;
6386 dev_item = btrfs_item_ptr(leaf, slot,
6387 struct btrfs_dev_item);
6388 ret = read_one_dev(root, leaf, dev_item);
6389 if (ret)
6390 goto error;
6391 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
6392 struct btrfs_chunk *chunk;
6393 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
6394 ret = read_one_chunk(root, &found_key, leaf, chunk);
6395 if (ret)
6396 goto error;
6397 }
6398 path->slots[0]++;
6399 }
6400 ret = 0;
6401 error:
6402 unlock_chunks(root);
6403 mutex_unlock(&uuid_mutex);
6404
6405 btrfs_free_path(path);
6406 return ret;
6407 }
6408
6409 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
6410 {
6411 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6412 struct btrfs_device *device;
6413
6414 while (fs_devices) {
6415 mutex_lock(&fs_devices->device_list_mutex);
6416 list_for_each_entry(device, &fs_devices->devices, dev_list)
6417 device->dev_root = fs_info->dev_root;
6418 mutex_unlock(&fs_devices->device_list_mutex);
6419
6420 fs_devices = fs_devices->seed;
6421 }
6422 }
6423
6424 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
6425 {
6426 int i;
6427
6428 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6429 btrfs_dev_stat_reset(dev, i);
6430 }
6431
6432 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
6433 {
6434 struct btrfs_key key;
6435 struct btrfs_key found_key;
6436 struct btrfs_root *dev_root = fs_info->dev_root;
6437 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6438 struct extent_buffer *eb;
6439 int slot;
6440 int ret = 0;
6441 struct btrfs_device *device;
6442 struct btrfs_path *path = NULL;
6443 int i;
6444
6445 path = btrfs_alloc_path();
6446 if (!path) {
6447 ret = -ENOMEM;
6448 goto out;
6449 }
6450
6451 mutex_lock(&fs_devices->device_list_mutex);
6452 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6453 int item_size;
6454 struct btrfs_dev_stats_item *ptr;
6455
6456 key.objectid = 0;
6457 key.type = BTRFS_DEV_STATS_KEY;
6458 key.offset = device->devid;
6459 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
6460 if (ret) {
6461 __btrfs_reset_dev_stats(device);
6462 device->dev_stats_valid = 1;
6463 btrfs_release_path(path);
6464 continue;
6465 }
6466 slot = path->slots[0];
6467 eb = path->nodes[0];
6468 btrfs_item_key_to_cpu(eb, &found_key, slot);
6469 item_size = btrfs_item_size_nr(eb, slot);
6470
6471 ptr = btrfs_item_ptr(eb, slot,
6472 struct btrfs_dev_stats_item);
6473
6474 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6475 if (item_size >= (1 + i) * sizeof(__le64))
6476 btrfs_dev_stat_set(device, i,
6477 btrfs_dev_stats_value(eb, ptr, i));
6478 else
6479 btrfs_dev_stat_reset(device, i);
6480 }
6481
6482 device->dev_stats_valid = 1;
6483 btrfs_dev_stat_print_on_load(device);
6484 btrfs_release_path(path);
6485 }
6486 mutex_unlock(&fs_devices->device_list_mutex);
6487
6488 out:
6489 btrfs_free_path(path);
6490 return ret < 0 ? ret : 0;
6491 }
6492
6493 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
6494 struct btrfs_root *dev_root,
6495 struct btrfs_device *device)
6496 {
6497 struct btrfs_path *path;
6498 struct btrfs_key key;
6499 struct extent_buffer *eb;
6500 struct btrfs_dev_stats_item *ptr;
6501 int ret;
6502 int i;
6503
6504 key.objectid = 0;
6505 key.type = BTRFS_DEV_STATS_KEY;
6506 key.offset = device->devid;
6507
6508 path = btrfs_alloc_path();
6509 BUG_ON(!path);
6510 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
6511 if (ret < 0) {
6512 printk_in_rcu(KERN_WARNING "BTRFS: "
6513 "error %d while searching for dev_stats item for device %s!\n",
6514 ret, rcu_str_deref(device->name));
6515 goto out;
6516 }
6517
6518 if (ret == 0 &&
6519 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
6520 /* need to delete old one and insert a new one */
6521 ret = btrfs_del_item(trans, dev_root, path);
6522 if (ret != 0) {
6523 printk_in_rcu(KERN_WARNING "BTRFS: "
6524 "delete too small dev_stats item for device %s failed %d!\n",
6525 rcu_str_deref(device->name), ret);
6526 goto out;
6527 }
6528 ret = 1;
6529 }
6530
6531 if (ret == 1) {
6532 /* need to insert a new item */
6533 btrfs_release_path(path);
6534 ret = btrfs_insert_empty_item(trans, dev_root, path,
6535 &key, sizeof(*ptr));
6536 if (ret < 0) {
6537 printk_in_rcu(KERN_WARNING "BTRFS: "
6538 "insert dev_stats item for device %s failed %d!\n",
6539 rcu_str_deref(device->name), ret);
6540 goto out;
6541 }
6542 }
6543
6544 eb = path->nodes[0];
6545 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
6546 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6547 btrfs_set_dev_stats_value(eb, ptr, i,
6548 btrfs_dev_stat_read(device, i));
6549 btrfs_mark_buffer_dirty(eb);
6550
6551 out:
6552 btrfs_free_path(path);
6553 return ret;
6554 }
6555
6556 /*
6557 * called from commit_transaction. Writes all changed device stats to disk.
6558 */
6559 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
6560 struct btrfs_fs_info *fs_info)
6561 {
6562 struct btrfs_root *dev_root = fs_info->dev_root;
6563 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6564 struct btrfs_device *device;
6565 int stats_cnt;
6566 int ret = 0;
6567
6568 mutex_lock(&fs_devices->device_list_mutex);
6569 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6570 if (!device->dev_stats_valid || !btrfs_dev_stats_dirty(device))
6571 continue;
6572
6573 stats_cnt = atomic_read(&device->dev_stats_ccnt);
6574 ret = update_dev_stat_item(trans, dev_root, device);
6575 if (!ret)
6576 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
6577 }
6578 mutex_unlock(&fs_devices->device_list_mutex);
6579
6580 return ret;
6581 }
6582
6583 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
6584 {
6585 btrfs_dev_stat_inc(dev, index);
6586 btrfs_dev_stat_print_on_error(dev);
6587 }
6588
6589 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
6590 {
6591 if (!dev->dev_stats_valid)
6592 return;
6593 printk_ratelimited_in_rcu(KERN_ERR "BTRFS: "
6594 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6595 rcu_str_deref(dev->name),
6596 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6597 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6598 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6599 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6600 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6601 }
6602
6603 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
6604 {
6605 int i;
6606
6607 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6608 if (btrfs_dev_stat_read(dev, i) != 0)
6609 break;
6610 if (i == BTRFS_DEV_STAT_VALUES_MAX)
6611 return; /* all values == 0, suppress message */
6612
6613 printk_in_rcu(KERN_INFO "BTRFS: "
6614 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6615 rcu_str_deref(dev->name),
6616 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6617 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6618 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6619 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6620 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6621 }
6622
6623 int btrfs_get_dev_stats(struct btrfs_root *root,
6624 struct btrfs_ioctl_get_dev_stats *stats)
6625 {
6626 struct btrfs_device *dev;
6627 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6628 int i;
6629
6630 mutex_lock(&fs_devices->device_list_mutex);
6631 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
6632 mutex_unlock(&fs_devices->device_list_mutex);
6633
6634 if (!dev) {
6635 btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
6636 return -ENODEV;
6637 } else if (!dev->dev_stats_valid) {
6638 btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
6639 return -ENODEV;
6640 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
6641 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6642 if (stats->nr_items > i)
6643 stats->values[i] =
6644 btrfs_dev_stat_read_and_reset(dev, i);
6645 else
6646 btrfs_dev_stat_reset(dev, i);
6647 }
6648 } else {
6649 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6650 if (stats->nr_items > i)
6651 stats->values[i] = btrfs_dev_stat_read(dev, i);
6652 }
6653 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
6654 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
6655 return 0;
6656 }
6657
6658 int btrfs_scratch_superblock(struct btrfs_device *device)
6659 {
6660 struct buffer_head *bh;
6661 struct btrfs_super_block *disk_super;
6662
6663 bh = btrfs_read_dev_super(device->bdev);
6664 if (!bh)
6665 return -EINVAL;
6666 disk_super = (struct btrfs_super_block *)bh->b_data;
6667
6668 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
6669 set_buffer_dirty(bh);
6670 sync_dirty_buffer(bh);
6671 brelse(bh);
6672
6673 return 0;
6674 }
6675
6676 /*
6677 * Update the size of all devices, which is used for writing out the
6678 * super blocks.
6679 */
6680 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info)
6681 {
6682 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6683 struct btrfs_device *curr, *next;
6684
6685 if (list_empty(&fs_devices->resized_devices))
6686 return;
6687
6688 mutex_lock(&fs_devices->device_list_mutex);
6689 lock_chunks(fs_info->dev_root);
6690 list_for_each_entry_safe(curr, next, &fs_devices->resized_devices,
6691 resized_list) {
6692 list_del_init(&curr->resized_list);
6693 curr->commit_total_bytes = curr->disk_total_bytes;
6694 }
6695 unlock_chunks(fs_info->dev_root);
6696 mutex_unlock(&fs_devices->device_list_mutex);
6697 }
6698
6699 /* Must be invoked during the transaction commit */
6700 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
6701 struct btrfs_transaction *transaction)
6702 {
6703 struct extent_map *em;
6704 struct map_lookup *map;
6705 struct btrfs_device *dev;
6706 int i;
6707
6708 if (list_empty(&transaction->pending_chunks))
6709 return;
6710
6711 /* In order to kick the device replace finish process */
6712 lock_chunks(root);
6713 list_for_each_entry(em, &transaction->pending_chunks, list) {
6714 map = (struct map_lookup *)em->bdev;
6715
6716 for (i = 0; i < map->num_stripes; i++) {
6717 dev = map->stripes[i].dev;
6718 dev->commit_bytes_used = dev->bytes_used;
6719 }
6720 }
6721 unlock_chunks(root);
6722 }
Linux kernel - Deliverables
This page took 0.789764 seconds and 6 git commands to generate.