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Merge tag 'mvebu-dt-4.2-3' of git://git.infradead.org/linux-mvebu into next/late
[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 u64 physical_start = *start;
1062
1063 again:
1064 list_for_each_entry(em, search_list, list) {
1065 struct map_lookup *map;
1066 int i;
1067
1068 map = (struct map_lookup *)em->bdev;
1069 for (i = 0; i < map->num_stripes; i++) {
1070 if (map->stripes[i].dev != device)
1071 continue;
1072 if (map->stripes[i].physical >= physical_start + len ||
1073 map->stripes[i].physical + em->orig_block_len <=
1074 physical_start)
1075 continue;
1076 *start = map->stripes[i].physical +
1077 em->orig_block_len;
1078 ret = 1;
1079 }
1080 }
1081 if (search_list == &trans->transaction->pending_chunks) {
1082 search_list = &trans->root->fs_info->pinned_chunks;
1083 goto again;
1084 }
1085
1086 return ret;
1087 }
1088
1089
1090 /*
1091 * find_free_dev_extent - find free space in the specified device
1092 * @device: the device which we search the free space in
1093 * @num_bytes: the size of the free space that we need
1094 * @start: store the start of the free space.
1095 * @len: the size of the free space. that we find, or the size of the max
1096 * free space if we don't find suitable free space
1097 *
1098 * this uses a pretty simple search, the expectation is that it is
1099 * called very infrequently and that a given device has a small number
1100 * of extents
1101 *
1102 * @start is used to store the start of the free space if we find. But if we
1103 * don't find suitable free space, it will be used to store the start position
1104 * of the max free space.
1105 *
1106 * @len is used to store the size of the free space that we find.
1107 * But if we don't find suitable free space, it is used to store the size of
1108 * the max free space.
1109 */
1110 int find_free_dev_extent(struct btrfs_trans_handle *trans,
1111 struct btrfs_device *device, u64 num_bytes,
1112 u64 *start, u64 *len)
1113 {
1114 struct btrfs_key key;
1115 struct btrfs_root *root = device->dev_root;
1116 struct btrfs_dev_extent *dev_extent;
1117 struct btrfs_path *path;
1118 u64 hole_size;
1119 u64 max_hole_start;
1120 u64 max_hole_size;
1121 u64 extent_end;
1122 u64 search_start;
1123 u64 search_end = device->total_bytes;
1124 int ret;
1125 int slot;
1126 struct extent_buffer *l;
1127
1128 /* FIXME use last free of some kind */
1129
1130 /* we don't want to overwrite the superblock on the drive,
1131 * so we make sure to start at an offset of at least 1MB
1132 */
1133 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
1134
1135 path = btrfs_alloc_path();
1136 if (!path)
1137 return -ENOMEM;
1138
1139 max_hole_start = search_start;
1140 max_hole_size = 0;
1141
1142 again:
1143 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
1144 ret = -ENOSPC;
1145 goto out;
1146 }
1147
1148 path->reada = 2;
1149 path->search_commit_root = 1;
1150 path->skip_locking = 1;
1151
1152 key.objectid = device->devid;
1153 key.offset = search_start;
1154 key.type = BTRFS_DEV_EXTENT_KEY;
1155
1156 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1157 if (ret < 0)
1158 goto out;
1159 if (ret > 0) {
1160 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1161 if (ret < 0)
1162 goto out;
1163 }
1164
1165 while (1) {
1166 l = path->nodes[0];
1167 slot = path->slots[0];
1168 if (slot >= btrfs_header_nritems(l)) {
1169 ret = btrfs_next_leaf(root, path);
1170 if (ret == 0)
1171 continue;
1172 if (ret < 0)
1173 goto out;
1174
1175 break;
1176 }
1177 btrfs_item_key_to_cpu(l, &key, slot);
1178
1179 if (key.objectid < device->devid)
1180 goto next;
1181
1182 if (key.objectid > device->devid)
1183 break;
1184
1185 if (key.type != BTRFS_DEV_EXTENT_KEY)
1186 goto next;
1187
1188 if (key.offset > search_start) {
1189 hole_size = key.offset - search_start;
1190
1191 /*
1192 * Have to check before we set max_hole_start, otherwise
1193 * we could end up sending back this offset anyway.
1194 */
1195 if (contains_pending_extent(trans, device,
1196 &search_start,
1197 hole_size)) {
1198 if (key.offset >= search_start) {
1199 hole_size = key.offset - search_start;
1200 } else {
1201 WARN_ON_ONCE(1);
1202 hole_size = 0;
1203 }
1204 }
1205
1206 if (hole_size > max_hole_size) {
1207 max_hole_start = search_start;
1208 max_hole_size = hole_size;
1209 }
1210
1211 /*
1212 * If this free space is greater than which we need,
1213 * it must be the max free space that we have found
1214 * until now, so max_hole_start must point to the start
1215 * of this free space and the length of this free space
1216 * is stored in max_hole_size. Thus, we return
1217 * max_hole_start and max_hole_size and go back to the
1218 * caller.
1219 */
1220 if (hole_size >= num_bytes) {
1221 ret = 0;
1222 goto out;
1223 }
1224 }
1225
1226 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1227 extent_end = key.offset + btrfs_dev_extent_length(l,
1228 dev_extent);
1229 if (extent_end > search_start)
1230 search_start = extent_end;
1231 next:
1232 path->slots[0]++;
1233 cond_resched();
1234 }
1235
1236 /*
1237 * At this point, search_start should be the end of
1238 * allocated dev extents, and when shrinking the device,
1239 * search_end may be smaller than search_start.
1240 */
1241 if (search_end > search_start) {
1242 hole_size = search_end - search_start;
1243
1244 if (contains_pending_extent(trans, device, &search_start,
1245 hole_size)) {
1246 btrfs_release_path(path);
1247 goto again;
1248 }
1249
1250 if (hole_size > max_hole_size) {
1251 max_hole_start = search_start;
1252 max_hole_size = hole_size;
1253 }
1254 }
1255
1256 /* See above. */
1257 if (max_hole_size < num_bytes)
1258 ret = -ENOSPC;
1259 else
1260 ret = 0;
1261
1262 out:
1263 btrfs_free_path(path);
1264 *start = max_hole_start;
1265 if (len)
1266 *len = max_hole_size;
1267 return ret;
1268 }
1269
1270 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1271 struct btrfs_device *device,
1272 u64 start, u64 *dev_extent_len)
1273 {
1274 int ret;
1275 struct btrfs_path *path;
1276 struct btrfs_root *root = device->dev_root;
1277 struct btrfs_key key;
1278 struct btrfs_key found_key;
1279 struct extent_buffer *leaf = NULL;
1280 struct btrfs_dev_extent *extent = NULL;
1281
1282 path = btrfs_alloc_path();
1283 if (!path)
1284 return -ENOMEM;
1285
1286 key.objectid = device->devid;
1287 key.offset = start;
1288 key.type = BTRFS_DEV_EXTENT_KEY;
1289 again:
1290 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1291 if (ret > 0) {
1292 ret = btrfs_previous_item(root, path, key.objectid,
1293 BTRFS_DEV_EXTENT_KEY);
1294 if (ret)
1295 goto out;
1296 leaf = path->nodes[0];
1297 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1298 extent = btrfs_item_ptr(leaf, path->slots[0],
1299 struct btrfs_dev_extent);
1300 BUG_ON(found_key.offset > start || found_key.offset +
1301 btrfs_dev_extent_length(leaf, extent) < start);
1302 key = found_key;
1303 btrfs_release_path(path);
1304 goto again;
1305 } else if (ret == 0) {
1306 leaf = path->nodes[0];
1307 extent = btrfs_item_ptr(leaf, path->slots[0],
1308 struct btrfs_dev_extent);
1309 } else {
1310 btrfs_error(root->fs_info, ret, "Slot search failed");
1311 goto out;
1312 }
1313
1314 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1315
1316 ret = btrfs_del_item(trans, root, path);
1317 if (ret) {
1318 btrfs_error(root->fs_info, ret,
1319 "Failed to remove dev extent item");
1320 } else {
1321 trans->transaction->have_free_bgs = 1;
1322 }
1323 out:
1324 btrfs_free_path(path);
1325 return ret;
1326 }
1327
1328 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1329 struct btrfs_device *device,
1330 u64 chunk_tree, u64 chunk_objectid,
1331 u64 chunk_offset, u64 start, u64 num_bytes)
1332 {
1333 int ret;
1334 struct btrfs_path *path;
1335 struct btrfs_root *root = device->dev_root;
1336 struct btrfs_dev_extent *extent;
1337 struct extent_buffer *leaf;
1338 struct btrfs_key key;
1339
1340 WARN_ON(!device->in_fs_metadata);
1341 WARN_ON(device->is_tgtdev_for_dev_replace);
1342 path = btrfs_alloc_path();
1343 if (!path)
1344 return -ENOMEM;
1345
1346 key.objectid = device->devid;
1347 key.offset = start;
1348 key.type = BTRFS_DEV_EXTENT_KEY;
1349 ret = btrfs_insert_empty_item(trans, root, path, &key,
1350 sizeof(*extent));
1351 if (ret)
1352 goto out;
1353
1354 leaf = path->nodes[0];
1355 extent = btrfs_item_ptr(leaf, path->slots[0],
1356 struct btrfs_dev_extent);
1357 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1358 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1359 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1360
1361 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1362 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE);
1363
1364 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1365 btrfs_mark_buffer_dirty(leaf);
1366 out:
1367 btrfs_free_path(path);
1368 return ret;
1369 }
1370
1371 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1372 {
1373 struct extent_map_tree *em_tree;
1374 struct extent_map *em;
1375 struct rb_node *n;
1376 u64 ret = 0;
1377
1378 em_tree = &fs_info->mapping_tree.map_tree;
1379 read_lock(&em_tree->lock);
1380 n = rb_last(&em_tree->map);
1381 if (n) {
1382 em = rb_entry(n, struct extent_map, rb_node);
1383 ret = em->start + em->len;
1384 }
1385 read_unlock(&em_tree->lock);
1386
1387 return ret;
1388 }
1389
1390 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1391 u64 *devid_ret)
1392 {
1393 int ret;
1394 struct btrfs_key key;
1395 struct btrfs_key found_key;
1396 struct btrfs_path *path;
1397
1398 path = btrfs_alloc_path();
1399 if (!path)
1400 return -ENOMEM;
1401
1402 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1403 key.type = BTRFS_DEV_ITEM_KEY;
1404 key.offset = (u64)-1;
1405
1406 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1407 if (ret < 0)
1408 goto error;
1409
1410 BUG_ON(ret == 0); /* Corruption */
1411
1412 ret = btrfs_previous_item(fs_info->chunk_root, path,
1413 BTRFS_DEV_ITEMS_OBJECTID,
1414 BTRFS_DEV_ITEM_KEY);
1415 if (ret) {
1416 *devid_ret = 1;
1417 } else {
1418 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1419 path->slots[0]);
1420 *devid_ret = found_key.offset + 1;
1421 }
1422 ret = 0;
1423 error:
1424 btrfs_free_path(path);
1425 return ret;
1426 }
1427
1428 /*
1429 * the device information is stored in the chunk root
1430 * the btrfs_device struct should be fully filled in
1431 */
1432 static int btrfs_add_device(struct btrfs_trans_handle *trans,
1433 struct btrfs_root *root,
1434 struct btrfs_device *device)
1435 {
1436 int ret;
1437 struct btrfs_path *path;
1438 struct btrfs_dev_item *dev_item;
1439 struct extent_buffer *leaf;
1440 struct btrfs_key key;
1441 unsigned long ptr;
1442
1443 root = root->fs_info->chunk_root;
1444
1445 path = btrfs_alloc_path();
1446 if (!path)
1447 return -ENOMEM;
1448
1449 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1450 key.type = BTRFS_DEV_ITEM_KEY;
1451 key.offset = device->devid;
1452
1453 ret = btrfs_insert_empty_item(trans, root, path, &key,
1454 sizeof(*dev_item));
1455 if (ret)
1456 goto out;
1457
1458 leaf = path->nodes[0];
1459 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1460
1461 btrfs_set_device_id(leaf, dev_item, device->devid);
1462 btrfs_set_device_generation(leaf, dev_item, 0);
1463 btrfs_set_device_type(leaf, dev_item, device->type);
1464 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1465 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1466 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1467 btrfs_set_device_total_bytes(leaf, dev_item,
1468 btrfs_device_get_disk_total_bytes(device));
1469 btrfs_set_device_bytes_used(leaf, dev_item,
1470 btrfs_device_get_bytes_used(device));
1471 btrfs_set_device_group(leaf, dev_item, 0);
1472 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1473 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1474 btrfs_set_device_start_offset(leaf, dev_item, 0);
1475
1476 ptr = btrfs_device_uuid(dev_item);
1477 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1478 ptr = btrfs_device_fsid(dev_item);
1479 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1480 btrfs_mark_buffer_dirty(leaf);
1481
1482 ret = 0;
1483 out:
1484 btrfs_free_path(path);
1485 return ret;
1486 }
1487
1488 /*
1489 * Function to update ctime/mtime for a given device path.
1490 * Mainly used for ctime/mtime based probe like libblkid.
1491 */
1492 static void update_dev_time(char *path_name)
1493 {
1494 struct file *filp;
1495
1496 filp = filp_open(path_name, O_RDWR, 0);
1497 if (IS_ERR(filp))
1498 return;
1499 file_update_time(filp);
1500 filp_close(filp, NULL);
1501 return;
1502 }
1503
1504 static int btrfs_rm_dev_item(struct btrfs_root *root,
1505 struct btrfs_device *device)
1506 {
1507 int ret;
1508 struct btrfs_path *path;
1509 struct btrfs_key key;
1510 struct btrfs_trans_handle *trans;
1511
1512 root = root->fs_info->chunk_root;
1513
1514 path = btrfs_alloc_path();
1515 if (!path)
1516 return -ENOMEM;
1517
1518 trans = btrfs_start_transaction(root, 0);
1519 if (IS_ERR(trans)) {
1520 btrfs_free_path(path);
1521 return PTR_ERR(trans);
1522 }
1523 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1524 key.type = BTRFS_DEV_ITEM_KEY;
1525 key.offset = device->devid;
1526
1527 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1528 if (ret < 0)
1529 goto out;
1530
1531 if (ret > 0) {
1532 ret = -ENOENT;
1533 goto out;
1534 }
1535
1536 ret = btrfs_del_item(trans, root, path);
1537 if (ret)
1538 goto out;
1539 out:
1540 btrfs_free_path(path);
1541 btrfs_commit_transaction(trans, root);
1542 return ret;
1543 }
1544
1545 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1546 {
1547 struct btrfs_device *device;
1548 struct btrfs_device *next_device;
1549 struct block_device *bdev;
1550 struct buffer_head *bh = NULL;
1551 struct btrfs_super_block *disk_super;
1552 struct btrfs_fs_devices *cur_devices;
1553 u64 all_avail;
1554 u64 devid;
1555 u64 num_devices;
1556 u8 *dev_uuid;
1557 unsigned seq;
1558 int ret = 0;
1559 bool clear_super = false;
1560
1561 mutex_lock(&uuid_mutex);
1562
1563 do {
1564 seq = read_seqbegin(&root->fs_info->profiles_lock);
1565
1566 all_avail = root->fs_info->avail_data_alloc_bits |
1567 root->fs_info->avail_system_alloc_bits |
1568 root->fs_info->avail_metadata_alloc_bits;
1569 } while (read_seqretry(&root->fs_info->profiles_lock, seq));
1570
1571 num_devices = root->fs_info->fs_devices->num_devices;
1572 btrfs_dev_replace_lock(&root->fs_info->dev_replace);
1573 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1574 WARN_ON(num_devices < 1);
1575 num_devices--;
1576 }
1577 btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
1578
1579 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
1580 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
1581 goto out;
1582 }
1583
1584 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
1585 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
1586 goto out;
1587 }
1588
1589 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
1590 root->fs_info->fs_devices->rw_devices <= 2) {
1591 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
1592 goto out;
1593 }
1594 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
1595 root->fs_info->fs_devices->rw_devices <= 3) {
1596 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
1597 goto out;
1598 }
1599
1600 if (strcmp(device_path, "missing") == 0) {
1601 struct list_head *devices;
1602 struct btrfs_device *tmp;
1603
1604 device = NULL;
1605 devices = &root->fs_info->fs_devices->devices;
1606 /*
1607 * It is safe to read the devices since the volume_mutex
1608 * is held.
1609 */
1610 list_for_each_entry(tmp, devices, dev_list) {
1611 if (tmp->in_fs_metadata &&
1612 !tmp->is_tgtdev_for_dev_replace &&
1613 !tmp->bdev) {
1614 device = tmp;
1615 break;
1616 }
1617 }
1618 bdev = NULL;
1619 bh = NULL;
1620 disk_super = NULL;
1621 if (!device) {
1622 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
1623 goto out;
1624 }
1625 } else {
1626 ret = btrfs_get_bdev_and_sb(device_path,
1627 FMODE_WRITE | FMODE_EXCL,
1628 root->fs_info->bdev_holder, 0,
1629 &bdev, &bh);
1630 if (ret)
1631 goto out;
1632 disk_super = (struct btrfs_super_block *)bh->b_data;
1633 devid = btrfs_stack_device_id(&disk_super->dev_item);
1634 dev_uuid = disk_super->dev_item.uuid;
1635 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1636 disk_super->fsid);
1637 if (!device) {
1638 ret = -ENOENT;
1639 goto error_brelse;
1640 }
1641 }
1642
1643 if (device->is_tgtdev_for_dev_replace) {
1644 ret = BTRFS_ERROR_DEV_TGT_REPLACE;
1645 goto error_brelse;
1646 }
1647
1648 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1649 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
1650 goto error_brelse;
1651 }
1652
1653 if (device->writeable) {
1654 lock_chunks(root);
1655 list_del_init(&device->dev_alloc_list);
1656 device->fs_devices->rw_devices--;
1657 unlock_chunks(root);
1658 clear_super = true;
1659 }
1660
1661 mutex_unlock(&uuid_mutex);
1662 ret = btrfs_shrink_device(device, 0);
1663 mutex_lock(&uuid_mutex);
1664 if (ret)
1665 goto error_undo;
1666
1667 /*
1668 * TODO: the superblock still includes this device in its num_devices
1669 * counter although write_all_supers() is not locked out. This
1670 * could give a filesystem state which requires a degraded mount.
1671 */
1672 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1673 if (ret)
1674 goto error_undo;
1675
1676 device->in_fs_metadata = 0;
1677 btrfs_scrub_cancel_dev(root->fs_info, device);
1678
1679 /*
1680 * the device list mutex makes sure that we don't change
1681 * the device list while someone else is writing out all
1682 * the device supers. Whoever is writing all supers, should
1683 * lock the device list mutex before getting the number of
1684 * devices in the super block (super_copy). Conversely,
1685 * whoever updates the number of devices in the super block
1686 * (super_copy) should hold the device list mutex.
1687 */
1688
1689 cur_devices = device->fs_devices;
1690 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1691 list_del_rcu(&device->dev_list);
1692
1693 device->fs_devices->num_devices--;
1694 device->fs_devices->total_devices--;
1695
1696 if (device->missing)
1697 device->fs_devices->missing_devices--;
1698
1699 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1700 struct btrfs_device, dev_list);
1701 if (device->bdev == root->fs_info->sb->s_bdev)
1702 root->fs_info->sb->s_bdev = next_device->bdev;
1703 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1704 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1705
1706 if (device->bdev) {
1707 device->fs_devices->open_devices--;
1708 /* remove sysfs entry */
1709 btrfs_kobj_rm_device(root->fs_info, device);
1710 }
1711
1712 call_rcu(&device->rcu, free_device);
1713
1714 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1715 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1716 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1717
1718 if (cur_devices->open_devices == 0) {
1719 struct btrfs_fs_devices *fs_devices;
1720 fs_devices = root->fs_info->fs_devices;
1721 while (fs_devices) {
1722 if (fs_devices->seed == cur_devices) {
1723 fs_devices->seed = cur_devices->seed;
1724 break;
1725 }
1726 fs_devices = fs_devices->seed;
1727 }
1728 cur_devices->seed = NULL;
1729 __btrfs_close_devices(cur_devices);
1730 free_fs_devices(cur_devices);
1731 }
1732
1733 root->fs_info->num_tolerated_disk_barrier_failures =
1734 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1735
1736 /*
1737 * at this point, the device is zero sized. We want to
1738 * remove it from the devices list and zero out the old super
1739 */
1740 if (clear_super && disk_super) {
1741 u64 bytenr;
1742 int i;
1743
1744 /* make sure this device isn't detected as part of
1745 * the FS anymore
1746 */
1747 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1748 set_buffer_dirty(bh);
1749 sync_dirty_buffer(bh);
1750
1751 /* clear the mirror copies of super block on the disk
1752 * being removed, 0th copy is been taken care above and
1753 * the below would take of the rest
1754 */
1755 for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1756 bytenr = btrfs_sb_offset(i);
1757 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
1758 i_size_read(bdev->bd_inode))
1759 break;
1760
1761 brelse(bh);
1762 bh = __bread(bdev, bytenr / 4096,
1763 BTRFS_SUPER_INFO_SIZE);
1764 if (!bh)
1765 continue;
1766
1767 disk_super = (struct btrfs_super_block *)bh->b_data;
1768
1769 if (btrfs_super_bytenr(disk_super) != bytenr ||
1770 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1771 continue;
1772 }
1773 memset(&disk_super->magic, 0,
1774 sizeof(disk_super->magic));
1775 set_buffer_dirty(bh);
1776 sync_dirty_buffer(bh);
1777 }
1778 }
1779
1780 ret = 0;
1781
1782 if (bdev) {
1783 /* Notify udev that device has changed */
1784 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
1785
1786 /* Update ctime/mtime for device path for libblkid */
1787 update_dev_time(device_path);
1788 }
1789
1790 error_brelse:
1791 brelse(bh);
1792 if (bdev)
1793 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1794 out:
1795 mutex_unlock(&uuid_mutex);
1796 return ret;
1797 error_undo:
1798 if (device->writeable) {
1799 lock_chunks(root);
1800 list_add(&device->dev_alloc_list,
1801 &root->fs_info->fs_devices->alloc_list);
1802 device->fs_devices->rw_devices++;
1803 unlock_chunks(root);
1804 }
1805 goto error_brelse;
1806 }
1807
1808 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
1809 struct btrfs_device *srcdev)
1810 {
1811 struct btrfs_fs_devices *fs_devices;
1812
1813 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1814
1815 /*
1816 * in case of fs with no seed, srcdev->fs_devices will point
1817 * to fs_devices of fs_info. However when the dev being replaced is
1818 * a seed dev it will point to the seed's local fs_devices. In short
1819 * srcdev will have its correct fs_devices in both the cases.
1820 */
1821 fs_devices = srcdev->fs_devices;
1822
1823 list_del_rcu(&srcdev->dev_list);
1824 list_del_rcu(&srcdev->dev_alloc_list);
1825 fs_devices->num_devices--;
1826 if (srcdev->missing)
1827 fs_devices->missing_devices--;
1828
1829 if (srcdev->writeable) {
1830 fs_devices->rw_devices--;
1831 /* zero out the old super if it is writable */
1832 btrfs_scratch_superblock(srcdev);
1833 }
1834
1835 if (srcdev->bdev)
1836 fs_devices->open_devices--;
1837 }
1838
1839 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
1840 struct btrfs_device *srcdev)
1841 {
1842 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
1843
1844 call_rcu(&srcdev->rcu, free_device);
1845
1846 /*
1847 * unless fs_devices is seed fs, num_devices shouldn't go
1848 * zero
1849 */
1850 BUG_ON(!fs_devices->num_devices && !fs_devices->seeding);
1851
1852 /* if this is no devs we rather delete the fs_devices */
1853 if (!fs_devices->num_devices) {
1854 struct btrfs_fs_devices *tmp_fs_devices;
1855
1856 tmp_fs_devices = fs_info->fs_devices;
1857 while (tmp_fs_devices) {
1858 if (tmp_fs_devices->seed == fs_devices) {
1859 tmp_fs_devices->seed = fs_devices->seed;
1860 break;
1861 }
1862 tmp_fs_devices = tmp_fs_devices->seed;
1863 }
1864 fs_devices->seed = NULL;
1865 __btrfs_close_devices(fs_devices);
1866 free_fs_devices(fs_devices);
1867 }
1868 }
1869
1870 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
1871 struct btrfs_device *tgtdev)
1872 {
1873 struct btrfs_device *next_device;
1874
1875 mutex_lock(&uuid_mutex);
1876 WARN_ON(!tgtdev);
1877 mutex_lock(&fs_info->fs_devices->device_list_mutex);
1878 if (tgtdev->bdev) {
1879 btrfs_scratch_superblock(tgtdev);
1880 fs_info->fs_devices->open_devices--;
1881 }
1882 fs_info->fs_devices->num_devices--;
1883
1884 next_device = list_entry(fs_info->fs_devices->devices.next,
1885 struct btrfs_device, dev_list);
1886 if (tgtdev->bdev == fs_info->sb->s_bdev)
1887 fs_info->sb->s_bdev = next_device->bdev;
1888 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
1889 fs_info->fs_devices->latest_bdev = next_device->bdev;
1890 list_del_rcu(&tgtdev->dev_list);
1891
1892 call_rcu(&tgtdev->rcu, free_device);
1893
1894 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
1895 mutex_unlock(&uuid_mutex);
1896 }
1897
1898 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
1899 struct btrfs_device **device)
1900 {
1901 int ret = 0;
1902 struct btrfs_super_block *disk_super;
1903 u64 devid;
1904 u8 *dev_uuid;
1905 struct block_device *bdev;
1906 struct buffer_head *bh;
1907
1908 *device = NULL;
1909 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ,
1910 root->fs_info->bdev_holder, 0, &bdev, &bh);
1911 if (ret)
1912 return ret;
1913 disk_super = (struct btrfs_super_block *)bh->b_data;
1914 devid = btrfs_stack_device_id(&disk_super->dev_item);
1915 dev_uuid = disk_super->dev_item.uuid;
1916 *device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1917 disk_super->fsid);
1918 brelse(bh);
1919 if (!*device)
1920 ret = -ENOENT;
1921 blkdev_put(bdev, FMODE_READ);
1922 return ret;
1923 }
1924
1925 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
1926 char *device_path,
1927 struct btrfs_device **device)
1928 {
1929 *device = NULL;
1930 if (strcmp(device_path, "missing") == 0) {
1931 struct list_head *devices;
1932 struct btrfs_device *tmp;
1933
1934 devices = &root->fs_info->fs_devices->devices;
1935 /*
1936 * It is safe to read the devices since the volume_mutex
1937 * is held by the caller.
1938 */
1939 list_for_each_entry(tmp, devices, dev_list) {
1940 if (tmp->in_fs_metadata && !tmp->bdev) {
1941 *device = tmp;
1942 break;
1943 }
1944 }
1945
1946 if (!*device) {
1947 btrfs_err(root->fs_info, "no missing device found");
1948 return -ENOENT;
1949 }
1950
1951 return 0;
1952 } else {
1953 return btrfs_find_device_by_path(root, device_path, device);
1954 }
1955 }
1956
1957 /*
1958 * does all the dirty work required for changing file system's UUID.
1959 */
1960 static int btrfs_prepare_sprout(struct btrfs_root *root)
1961 {
1962 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1963 struct btrfs_fs_devices *old_devices;
1964 struct btrfs_fs_devices *seed_devices;
1965 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
1966 struct btrfs_device *device;
1967 u64 super_flags;
1968
1969 BUG_ON(!mutex_is_locked(&uuid_mutex));
1970 if (!fs_devices->seeding)
1971 return -EINVAL;
1972
1973 seed_devices = __alloc_fs_devices();
1974 if (IS_ERR(seed_devices))
1975 return PTR_ERR(seed_devices);
1976
1977 old_devices = clone_fs_devices(fs_devices);
1978 if (IS_ERR(old_devices)) {
1979 kfree(seed_devices);
1980 return PTR_ERR(old_devices);
1981 }
1982
1983 list_add(&old_devices->list, &fs_uuids);
1984
1985 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1986 seed_devices->opened = 1;
1987 INIT_LIST_HEAD(&seed_devices->devices);
1988 INIT_LIST_HEAD(&seed_devices->alloc_list);
1989 mutex_init(&seed_devices->device_list_mutex);
1990
1991 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1992 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
1993 synchronize_rcu);
1994 list_for_each_entry(device, &seed_devices->devices, dev_list)
1995 device->fs_devices = seed_devices;
1996
1997 lock_chunks(root);
1998 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1999 unlock_chunks(root);
2000
2001 fs_devices->seeding = 0;
2002 fs_devices->num_devices = 0;
2003 fs_devices->open_devices = 0;
2004 fs_devices->missing_devices = 0;
2005 fs_devices->rotating = 0;
2006 fs_devices->seed = seed_devices;
2007
2008 generate_random_uuid(fs_devices->fsid);
2009 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2010 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2011 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2012
2013 super_flags = btrfs_super_flags(disk_super) &
2014 ~BTRFS_SUPER_FLAG_SEEDING;
2015 btrfs_set_super_flags(disk_super, super_flags);
2016
2017 return 0;
2018 }
2019
2020 /*
2021 * strore the expected generation for seed devices in device items.
2022 */
2023 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
2024 struct btrfs_root *root)
2025 {
2026 struct btrfs_path *path;
2027 struct extent_buffer *leaf;
2028 struct btrfs_dev_item *dev_item;
2029 struct btrfs_device *device;
2030 struct btrfs_key key;
2031 u8 fs_uuid[BTRFS_UUID_SIZE];
2032 u8 dev_uuid[BTRFS_UUID_SIZE];
2033 u64 devid;
2034 int ret;
2035
2036 path = btrfs_alloc_path();
2037 if (!path)
2038 return -ENOMEM;
2039
2040 root = root->fs_info->chunk_root;
2041 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2042 key.offset = 0;
2043 key.type = BTRFS_DEV_ITEM_KEY;
2044
2045 while (1) {
2046 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2047 if (ret < 0)
2048 goto error;
2049
2050 leaf = path->nodes[0];
2051 next_slot:
2052 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2053 ret = btrfs_next_leaf(root, path);
2054 if (ret > 0)
2055 break;
2056 if (ret < 0)
2057 goto error;
2058 leaf = path->nodes[0];
2059 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2060 btrfs_release_path(path);
2061 continue;
2062 }
2063
2064 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2065 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2066 key.type != BTRFS_DEV_ITEM_KEY)
2067 break;
2068
2069 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2070 struct btrfs_dev_item);
2071 devid = btrfs_device_id(leaf, dev_item);
2072 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2073 BTRFS_UUID_SIZE);
2074 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2075 BTRFS_UUID_SIZE);
2076 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2077 fs_uuid);
2078 BUG_ON(!device); /* Logic error */
2079
2080 if (device->fs_devices->seeding) {
2081 btrfs_set_device_generation(leaf, dev_item,
2082 device->generation);
2083 btrfs_mark_buffer_dirty(leaf);
2084 }
2085
2086 path->slots[0]++;
2087 goto next_slot;
2088 }
2089 ret = 0;
2090 error:
2091 btrfs_free_path(path);
2092 return ret;
2093 }
2094
2095 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
2096 {
2097 struct request_queue *q;
2098 struct btrfs_trans_handle *trans;
2099 struct btrfs_device *device;
2100 struct block_device *bdev;
2101 struct list_head *devices;
2102 struct super_block *sb = root->fs_info->sb;
2103 struct rcu_string *name;
2104 u64 tmp;
2105 int seeding_dev = 0;
2106 int ret = 0;
2107
2108 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
2109 return -EROFS;
2110
2111 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2112 root->fs_info->bdev_holder);
2113 if (IS_ERR(bdev))
2114 return PTR_ERR(bdev);
2115
2116 if (root->fs_info->fs_devices->seeding) {
2117 seeding_dev = 1;
2118 down_write(&sb->s_umount);
2119 mutex_lock(&uuid_mutex);
2120 }
2121
2122 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2123
2124 devices = &root->fs_info->fs_devices->devices;
2125
2126 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2127 list_for_each_entry(device, devices, dev_list) {
2128 if (device->bdev == bdev) {
2129 ret = -EEXIST;
2130 mutex_unlock(
2131 &root->fs_info->fs_devices->device_list_mutex);
2132 goto error;
2133 }
2134 }
2135 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2136
2137 device = btrfs_alloc_device(root->fs_info, NULL, NULL);
2138 if (IS_ERR(device)) {
2139 /* we can safely leave the fs_devices entry around */
2140 ret = PTR_ERR(device);
2141 goto error;
2142 }
2143
2144 name = rcu_string_strdup(device_path, GFP_NOFS);
2145 if (!name) {
2146 kfree(device);
2147 ret = -ENOMEM;
2148 goto error;
2149 }
2150 rcu_assign_pointer(device->name, name);
2151
2152 trans = btrfs_start_transaction(root, 0);
2153 if (IS_ERR(trans)) {
2154 rcu_string_free(device->name);
2155 kfree(device);
2156 ret = PTR_ERR(trans);
2157 goto error;
2158 }
2159
2160 q = bdev_get_queue(bdev);
2161 if (blk_queue_discard(q))
2162 device->can_discard = 1;
2163 device->writeable = 1;
2164 device->generation = trans->transid;
2165 device->io_width = root->sectorsize;
2166 device->io_align = root->sectorsize;
2167 device->sector_size = root->sectorsize;
2168 device->total_bytes = i_size_read(bdev->bd_inode);
2169 device->disk_total_bytes = device->total_bytes;
2170 device->commit_total_bytes = device->total_bytes;
2171 device->dev_root = root->fs_info->dev_root;
2172 device->bdev = bdev;
2173 device->in_fs_metadata = 1;
2174 device->is_tgtdev_for_dev_replace = 0;
2175 device->mode = FMODE_EXCL;
2176 device->dev_stats_valid = 1;
2177 set_blocksize(device->bdev, 4096);
2178
2179 if (seeding_dev) {
2180 sb->s_flags &= ~MS_RDONLY;
2181 ret = btrfs_prepare_sprout(root);
2182 BUG_ON(ret); /* -ENOMEM */
2183 }
2184
2185 device->fs_devices = root->fs_info->fs_devices;
2186
2187 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2188 lock_chunks(root);
2189 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
2190 list_add(&device->dev_alloc_list,
2191 &root->fs_info->fs_devices->alloc_list);
2192 root->fs_info->fs_devices->num_devices++;
2193 root->fs_info->fs_devices->open_devices++;
2194 root->fs_info->fs_devices->rw_devices++;
2195 root->fs_info->fs_devices->total_devices++;
2196 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
2197
2198 spin_lock(&root->fs_info->free_chunk_lock);
2199 root->fs_info->free_chunk_space += device->total_bytes;
2200 spin_unlock(&root->fs_info->free_chunk_lock);
2201
2202 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
2203 root->fs_info->fs_devices->rotating = 1;
2204
2205 tmp = btrfs_super_total_bytes(root->fs_info->super_copy);
2206 btrfs_set_super_total_bytes(root->fs_info->super_copy,
2207 tmp + device->total_bytes);
2208
2209 tmp = btrfs_super_num_devices(root->fs_info->super_copy);
2210 btrfs_set_super_num_devices(root->fs_info->super_copy,
2211 tmp + 1);
2212
2213 /* add sysfs device entry */
2214 btrfs_kobj_add_device(root->fs_info, device);
2215
2216 /*
2217 * we've got more storage, clear any full flags on the space
2218 * infos
2219 */
2220 btrfs_clear_space_info_full(root->fs_info);
2221
2222 unlock_chunks(root);
2223 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2224
2225 if (seeding_dev) {
2226 lock_chunks(root);
2227 ret = init_first_rw_device(trans, root, device);
2228 unlock_chunks(root);
2229 if (ret) {
2230 btrfs_abort_transaction(trans, root, ret);
2231 goto error_trans;
2232 }
2233 }
2234
2235 ret = btrfs_add_device(trans, root, device);
2236 if (ret) {
2237 btrfs_abort_transaction(trans, root, ret);
2238 goto error_trans;
2239 }
2240
2241 if (seeding_dev) {
2242 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2243
2244 ret = btrfs_finish_sprout(trans, root);
2245 if (ret) {
2246 btrfs_abort_transaction(trans, root, ret);
2247 goto error_trans;
2248 }
2249
2250 /* Sprouting would change fsid of the mounted root,
2251 * so rename the fsid on the sysfs
2252 */
2253 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU",
2254 root->fs_info->fsid);
2255 if (kobject_rename(&root->fs_info->super_kobj, fsid_buf))
2256 goto error_trans;
2257 }
2258
2259 root->fs_info->num_tolerated_disk_barrier_failures =
2260 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2261 ret = btrfs_commit_transaction(trans, root);
2262
2263 if (seeding_dev) {
2264 mutex_unlock(&uuid_mutex);
2265 up_write(&sb->s_umount);
2266
2267 if (ret) /* transaction commit */
2268 return ret;
2269
2270 ret = btrfs_relocate_sys_chunks(root);
2271 if (ret < 0)
2272 btrfs_error(root->fs_info, ret,
2273 "Failed to relocate sys chunks after "
2274 "device initialization. This can be fixed "
2275 "using the \"btrfs balance\" command.");
2276 trans = btrfs_attach_transaction(root);
2277 if (IS_ERR(trans)) {
2278 if (PTR_ERR(trans) == -ENOENT)
2279 return 0;
2280 return PTR_ERR(trans);
2281 }
2282 ret = btrfs_commit_transaction(trans, root);
2283 }
2284
2285 /* Update ctime/mtime for libblkid */
2286 update_dev_time(device_path);
2287 return ret;
2288
2289 error_trans:
2290 btrfs_end_transaction(trans, root);
2291 rcu_string_free(device->name);
2292 btrfs_kobj_rm_device(root->fs_info, device);
2293 kfree(device);
2294 error:
2295 blkdev_put(bdev, FMODE_EXCL);
2296 if (seeding_dev) {
2297 mutex_unlock(&uuid_mutex);
2298 up_write(&sb->s_umount);
2299 }
2300 return ret;
2301 }
2302
2303 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2304 struct btrfs_device *srcdev,
2305 struct btrfs_device **device_out)
2306 {
2307 struct request_queue *q;
2308 struct btrfs_device *device;
2309 struct block_device *bdev;
2310 struct btrfs_fs_info *fs_info = root->fs_info;
2311 struct list_head *devices;
2312 struct rcu_string *name;
2313 u64 devid = BTRFS_DEV_REPLACE_DEVID;
2314 int ret = 0;
2315
2316 *device_out = NULL;
2317 if (fs_info->fs_devices->seeding) {
2318 btrfs_err(fs_info, "the filesystem is a seed filesystem!");
2319 return -EINVAL;
2320 }
2321
2322 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2323 fs_info->bdev_holder);
2324 if (IS_ERR(bdev)) {
2325 btrfs_err(fs_info, "target device %s is invalid!", device_path);
2326 return PTR_ERR(bdev);
2327 }
2328
2329 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2330
2331 devices = &fs_info->fs_devices->devices;
2332 list_for_each_entry(device, devices, dev_list) {
2333 if (device->bdev == bdev) {
2334 btrfs_err(fs_info, "target device is in the filesystem!");
2335 ret = -EEXIST;
2336 goto error;
2337 }
2338 }
2339
2340
2341 if (i_size_read(bdev->bd_inode) <
2342 btrfs_device_get_total_bytes(srcdev)) {
2343 btrfs_err(fs_info, "target device is smaller than source device!");
2344 ret = -EINVAL;
2345 goto error;
2346 }
2347
2348
2349 device = btrfs_alloc_device(NULL, &devid, NULL);
2350 if (IS_ERR(device)) {
2351 ret = PTR_ERR(device);
2352 goto error;
2353 }
2354
2355 name = rcu_string_strdup(device_path, GFP_NOFS);
2356 if (!name) {
2357 kfree(device);
2358 ret = -ENOMEM;
2359 goto error;
2360 }
2361 rcu_assign_pointer(device->name, name);
2362
2363 q = bdev_get_queue(bdev);
2364 if (blk_queue_discard(q))
2365 device->can_discard = 1;
2366 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2367 device->writeable = 1;
2368 device->generation = 0;
2369 device->io_width = root->sectorsize;
2370 device->io_align = root->sectorsize;
2371 device->sector_size = root->sectorsize;
2372 device->total_bytes = btrfs_device_get_total_bytes(srcdev);
2373 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev);
2374 device->bytes_used = btrfs_device_get_bytes_used(srcdev);
2375 ASSERT(list_empty(&srcdev->resized_list));
2376 device->commit_total_bytes = srcdev->commit_total_bytes;
2377 device->commit_bytes_used = device->bytes_used;
2378 device->dev_root = fs_info->dev_root;
2379 device->bdev = bdev;
2380 device->in_fs_metadata = 1;
2381 device->is_tgtdev_for_dev_replace = 1;
2382 device->mode = FMODE_EXCL;
2383 device->dev_stats_valid = 1;
2384 set_blocksize(device->bdev, 4096);
2385 device->fs_devices = fs_info->fs_devices;
2386 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2387 fs_info->fs_devices->num_devices++;
2388 fs_info->fs_devices->open_devices++;
2389 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2390
2391 *device_out = device;
2392 return ret;
2393
2394 error:
2395 blkdev_put(bdev, FMODE_EXCL);
2396 return ret;
2397 }
2398
2399 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2400 struct btrfs_device *tgtdev)
2401 {
2402 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2403 tgtdev->io_width = fs_info->dev_root->sectorsize;
2404 tgtdev->io_align = fs_info->dev_root->sectorsize;
2405 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2406 tgtdev->dev_root = fs_info->dev_root;
2407 tgtdev->in_fs_metadata = 1;
2408 }
2409
2410 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2411 struct btrfs_device *device)
2412 {
2413 int ret;
2414 struct btrfs_path *path;
2415 struct btrfs_root *root;
2416 struct btrfs_dev_item *dev_item;
2417 struct extent_buffer *leaf;
2418 struct btrfs_key key;
2419
2420 root = device->dev_root->fs_info->chunk_root;
2421
2422 path = btrfs_alloc_path();
2423 if (!path)
2424 return -ENOMEM;
2425
2426 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2427 key.type = BTRFS_DEV_ITEM_KEY;
2428 key.offset = device->devid;
2429
2430 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2431 if (ret < 0)
2432 goto out;
2433
2434 if (ret > 0) {
2435 ret = -ENOENT;
2436 goto out;
2437 }
2438
2439 leaf = path->nodes[0];
2440 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2441
2442 btrfs_set_device_id(leaf, dev_item, device->devid);
2443 btrfs_set_device_type(leaf, dev_item, device->type);
2444 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2445 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2446 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2447 btrfs_set_device_total_bytes(leaf, dev_item,
2448 btrfs_device_get_disk_total_bytes(device));
2449 btrfs_set_device_bytes_used(leaf, dev_item,
2450 btrfs_device_get_bytes_used(device));
2451 btrfs_mark_buffer_dirty(leaf);
2452
2453 out:
2454 btrfs_free_path(path);
2455 return ret;
2456 }
2457
2458 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2459 struct btrfs_device *device, u64 new_size)
2460 {
2461 struct btrfs_super_block *super_copy =
2462 device->dev_root->fs_info->super_copy;
2463 struct btrfs_fs_devices *fs_devices;
2464 u64 old_total;
2465 u64 diff;
2466
2467 if (!device->writeable)
2468 return -EACCES;
2469
2470 lock_chunks(device->dev_root);
2471 old_total = btrfs_super_total_bytes(super_copy);
2472 diff = new_size - device->total_bytes;
2473
2474 if (new_size <= device->total_bytes ||
2475 device->is_tgtdev_for_dev_replace) {
2476 unlock_chunks(device->dev_root);
2477 return -EINVAL;
2478 }
2479
2480 fs_devices = device->dev_root->fs_info->fs_devices;
2481
2482 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2483 device->fs_devices->total_rw_bytes += diff;
2484
2485 btrfs_device_set_total_bytes(device, new_size);
2486 btrfs_device_set_disk_total_bytes(device, new_size);
2487 btrfs_clear_space_info_full(device->dev_root->fs_info);
2488 if (list_empty(&device->resized_list))
2489 list_add_tail(&device->resized_list,
2490 &fs_devices->resized_devices);
2491 unlock_chunks(device->dev_root);
2492
2493 return btrfs_update_device(trans, device);
2494 }
2495
2496 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2497 struct btrfs_root *root, u64 chunk_objectid,
2498 u64 chunk_offset)
2499 {
2500 int ret;
2501 struct btrfs_path *path;
2502 struct btrfs_key key;
2503
2504 root = root->fs_info->chunk_root;
2505 path = btrfs_alloc_path();
2506 if (!path)
2507 return -ENOMEM;
2508
2509 key.objectid = chunk_objectid;
2510 key.offset = chunk_offset;
2511 key.type = BTRFS_CHUNK_ITEM_KEY;
2512
2513 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2514 if (ret < 0)
2515 goto out;
2516 else if (ret > 0) { /* Logic error or corruption */
2517 btrfs_error(root->fs_info, -ENOENT,
2518 "Failed lookup while freeing chunk.");
2519 ret = -ENOENT;
2520 goto out;
2521 }
2522
2523 ret = btrfs_del_item(trans, root, path);
2524 if (ret < 0)
2525 btrfs_error(root->fs_info, ret,
2526 "Failed to delete chunk item.");
2527 out:
2528 btrfs_free_path(path);
2529 return ret;
2530 }
2531
2532 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2533 chunk_offset)
2534 {
2535 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2536 struct btrfs_disk_key *disk_key;
2537 struct btrfs_chunk *chunk;
2538 u8 *ptr;
2539 int ret = 0;
2540 u32 num_stripes;
2541 u32 array_size;
2542 u32 len = 0;
2543 u32 cur;
2544 struct btrfs_key key;
2545
2546 lock_chunks(root);
2547 array_size = btrfs_super_sys_array_size(super_copy);
2548
2549 ptr = super_copy->sys_chunk_array;
2550 cur = 0;
2551
2552 while (cur < array_size) {
2553 disk_key = (struct btrfs_disk_key *)ptr;
2554 btrfs_disk_key_to_cpu(&key, disk_key);
2555
2556 len = sizeof(*disk_key);
2557
2558 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2559 chunk = (struct btrfs_chunk *)(ptr + len);
2560 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2561 len += btrfs_chunk_item_size(num_stripes);
2562 } else {
2563 ret = -EIO;
2564 break;
2565 }
2566 if (key.objectid == chunk_objectid &&
2567 key.offset == chunk_offset) {
2568 memmove(ptr, ptr + len, array_size - (cur + len));
2569 array_size -= len;
2570 btrfs_set_super_sys_array_size(super_copy, array_size);
2571 } else {
2572 ptr += len;
2573 cur += len;
2574 }
2575 }
2576 unlock_chunks(root);
2577 return ret;
2578 }
2579
2580 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
2581 struct btrfs_root *root, u64 chunk_offset)
2582 {
2583 struct extent_map_tree *em_tree;
2584 struct extent_map *em;
2585 struct btrfs_root *extent_root = root->fs_info->extent_root;
2586 struct map_lookup *map;
2587 u64 dev_extent_len = 0;
2588 u64 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2589 int i, ret = 0;
2590
2591 /* Just in case */
2592 root = root->fs_info->chunk_root;
2593 em_tree = &root->fs_info->mapping_tree.map_tree;
2594
2595 read_lock(&em_tree->lock);
2596 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2597 read_unlock(&em_tree->lock);
2598
2599 if (!em || em->start > chunk_offset ||
2600 em->start + em->len < chunk_offset) {
2601 /*
2602 * This is a logic error, but we don't want to just rely on the
2603 * user having built with ASSERT enabled, so if ASSERT doens't
2604 * do anything we still error out.
2605 */
2606 ASSERT(0);
2607 if (em)
2608 free_extent_map(em);
2609 return -EINVAL;
2610 }
2611 map = (struct map_lookup *)em->bdev;
2612
2613 for (i = 0; i < map->num_stripes; i++) {
2614 struct btrfs_device *device = map->stripes[i].dev;
2615 ret = btrfs_free_dev_extent(trans, device,
2616 map->stripes[i].physical,
2617 &dev_extent_len);
2618 if (ret) {
2619 btrfs_abort_transaction(trans, root, ret);
2620 goto out;
2621 }
2622
2623 if (device->bytes_used > 0) {
2624 lock_chunks(root);
2625 btrfs_device_set_bytes_used(device,
2626 device->bytes_used - dev_extent_len);
2627 spin_lock(&root->fs_info->free_chunk_lock);
2628 root->fs_info->free_chunk_space += dev_extent_len;
2629 spin_unlock(&root->fs_info->free_chunk_lock);
2630 btrfs_clear_space_info_full(root->fs_info);
2631 unlock_chunks(root);
2632 }
2633
2634 if (map->stripes[i].dev) {
2635 ret = btrfs_update_device(trans, map->stripes[i].dev);
2636 if (ret) {
2637 btrfs_abort_transaction(trans, root, ret);
2638 goto out;
2639 }
2640 }
2641 }
2642 ret = btrfs_free_chunk(trans, root, chunk_objectid, chunk_offset);
2643 if (ret) {
2644 btrfs_abort_transaction(trans, root, ret);
2645 goto out;
2646 }
2647
2648 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2649
2650 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2651 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2652 if (ret) {
2653 btrfs_abort_transaction(trans, root, ret);
2654 goto out;
2655 }
2656 }
2657
2658 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset, em);
2659 if (ret) {
2660 btrfs_abort_transaction(trans, extent_root, ret);
2661 goto out;
2662 }
2663
2664 out:
2665 /* once for us */
2666 free_extent_map(em);
2667 return ret;
2668 }
2669
2670 static int btrfs_relocate_chunk(struct btrfs_root *root,
2671 u64 chunk_objectid,
2672 u64 chunk_offset)
2673 {
2674 struct btrfs_root *extent_root;
2675 struct btrfs_trans_handle *trans;
2676 int ret;
2677
2678 root = root->fs_info->chunk_root;
2679 extent_root = root->fs_info->extent_root;
2680
2681 ret = btrfs_can_relocate(extent_root, chunk_offset);
2682 if (ret)
2683 return -ENOSPC;
2684
2685 /* step one, relocate all the extents inside this chunk */
2686 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2687 if (ret)
2688 return ret;
2689
2690 trans = btrfs_start_transaction(root, 0);
2691 if (IS_ERR(trans)) {
2692 ret = PTR_ERR(trans);
2693 btrfs_std_error(root->fs_info, ret);
2694 return ret;
2695 }
2696
2697 /*
2698 * step two, delete the device extents and the
2699 * chunk tree entries
2700 */
2701 ret = btrfs_remove_chunk(trans, root, chunk_offset);
2702 btrfs_end_transaction(trans, root);
2703 return ret;
2704 }
2705
2706 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2707 {
2708 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2709 struct btrfs_path *path;
2710 struct extent_buffer *leaf;
2711 struct btrfs_chunk *chunk;
2712 struct btrfs_key key;
2713 struct btrfs_key found_key;
2714 u64 chunk_type;
2715 bool retried = false;
2716 int failed = 0;
2717 int ret;
2718
2719 path = btrfs_alloc_path();
2720 if (!path)
2721 return -ENOMEM;
2722
2723 again:
2724 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2725 key.offset = (u64)-1;
2726 key.type = BTRFS_CHUNK_ITEM_KEY;
2727
2728 while (1) {
2729 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2730 if (ret < 0)
2731 goto error;
2732 BUG_ON(ret == 0); /* Corruption */
2733
2734 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2735 key.type);
2736 if (ret < 0)
2737 goto error;
2738 if (ret > 0)
2739 break;
2740
2741 leaf = path->nodes[0];
2742 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2743
2744 chunk = btrfs_item_ptr(leaf, path->slots[0],
2745 struct btrfs_chunk);
2746 chunk_type = btrfs_chunk_type(leaf, chunk);
2747 btrfs_release_path(path);
2748
2749 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2750 ret = btrfs_relocate_chunk(chunk_root,
2751 found_key.objectid,
2752 found_key.offset);
2753 if (ret == -ENOSPC)
2754 failed++;
2755 else
2756 BUG_ON(ret);
2757 }
2758
2759 if (found_key.offset == 0)
2760 break;
2761 key.offset = found_key.offset - 1;
2762 }
2763 ret = 0;
2764 if (failed && !retried) {
2765 failed = 0;
2766 retried = true;
2767 goto again;
2768 } else if (WARN_ON(failed && retried)) {
2769 ret = -ENOSPC;
2770 }
2771 error:
2772 btrfs_free_path(path);
2773 return ret;
2774 }
2775
2776 static int insert_balance_item(struct btrfs_root *root,
2777 struct btrfs_balance_control *bctl)
2778 {
2779 struct btrfs_trans_handle *trans;
2780 struct btrfs_balance_item *item;
2781 struct btrfs_disk_balance_args disk_bargs;
2782 struct btrfs_path *path;
2783 struct extent_buffer *leaf;
2784 struct btrfs_key key;
2785 int ret, err;
2786
2787 path = btrfs_alloc_path();
2788 if (!path)
2789 return -ENOMEM;
2790
2791 trans = btrfs_start_transaction(root, 0);
2792 if (IS_ERR(trans)) {
2793 btrfs_free_path(path);
2794 return PTR_ERR(trans);
2795 }
2796
2797 key.objectid = BTRFS_BALANCE_OBJECTID;
2798 key.type = BTRFS_BALANCE_ITEM_KEY;
2799 key.offset = 0;
2800
2801 ret = btrfs_insert_empty_item(trans, root, path, &key,
2802 sizeof(*item));
2803 if (ret)
2804 goto out;
2805
2806 leaf = path->nodes[0];
2807 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2808
2809 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2810
2811 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2812 btrfs_set_balance_data(leaf, item, &disk_bargs);
2813 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2814 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2815 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2816 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2817
2818 btrfs_set_balance_flags(leaf, item, bctl->flags);
2819
2820 btrfs_mark_buffer_dirty(leaf);
2821 out:
2822 btrfs_free_path(path);
2823 err = btrfs_commit_transaction(trans, root);
2824 if (err && !ret)
2825 ret = err;
2826 return ret;
2827 }
2828
2829 static int del_balance_item(struct btrfs_root *root)
2830 {
2831 struct btrfs_trans_handle *trans;
2832 struct btrfs_path *path;
2833 struct btrfs_key key;
2834 int ret, err;
2835
2836 path = btrfs_alloc_path();
2837 if (!path)
2838 return -ENOMEM;
2839
2840 trans = btrfs_start_transaction(root, 0);
2841 if (IS_ERR(trans)) {
2842 btrfs_free_path(path);
2843 return PTR_ERR(trans);
2844 }
2845
2846 key.objectid = BTRFS_BALANCE_OBJECTID;
2847 key.type = BTRFS_BALANCE_ITEM_KEY;
2848 key.offset = 0;
2849
2850 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2851 if (ret < 0)
2852 goto out;
2853 if (ret > 0) {
2854 ret = -ENOENT;
2855 goto out;
2856 }
2857
2858 ret = btrfs_del_item(trans, root, path);
2859 out:
2860 btrfs_free_path(path);
2861 err = btrfs_commit_transaction(trans, root);
2862 if (err && !ret)
2863 ret = err;
2864 return ret;
2865 }
2866
2867 /*
2868 * This is a heuristic used to reduce the number of chunks balanced on
2869 * resume after balance was interrupted.
2870 */
2871 static void update_balance_args(struct btrfs_balance_control *bctl)
2872 {
2873 /*
2874 * Turn on soft mode for chunk types that were being converted.
2875 */
2876 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
2877 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
2878 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
2879 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
2880 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
2881 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
2882
2883 /*
2884 * Turn on usage filter if is not already used. The idea is
2885 * that chunks that we have already balanced should be
2886 * reasonably full. Don't do it for chunks that are being
2887 * converted - that will keep us from relocating unconverted
2888 * (albeit full) chunks.
2889 */
2890 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2891 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2892 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
2893 bctl->data.usage = 90;
2894 }
2895 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2896 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2897 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
2898 bctl->sys.usage = 90;
2899 }
2900 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2901 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2902 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
2903 bctl->meta.usage = 90;
2904 }
2905 }
2906
2907 /*
2908 * Should be called with both balance and volume mutexes held to
2909 * serialize other volume operations (add_dev/rm_dev/resize) with
2910 * restriper. Same goes for unset_balance_control.
2911 */
2912 static void set_balance_control(struct btrfs_balance_control *bctl)
2913 {
2914 struct btrfs_fs_info *fs_info = bctl->fs_info;
2915
2916 BUG_ON(fs_info->balance_ctl);
2917
2918 spin_lock(&fs_info->balance_lock);
2919 fs_info->balance_ctl = bctl;
2920 spin_unlock(&fs_info->balance_lock);
2921 }
2922
2923 static void unset_balance_control(struct btrfs_fs_info *fs_info)
2924 {
2925 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
2926
2927 BUG_ON(!fs_info->balance_ctl);
2928
2929 spin_lock(&fs_info->balance_lock);
2930 fs_info->balance_ctl = NULL;
2931 spin_unlock(&fs_info->balance_lock);
2932
2933 kfree(bctl);
2934 }
2935
2936 /*
2937 * Balance filters. Return 1 if chunk should be filtered out
2938 * (should not be balanced).
2939 */
2940 static int chunk_profiles_filter(u64 chunk_type,
2941 struct btrfs_balance_args *bargs)
2942 {
2943 chunk_type = chunk_to_extended(chunk_type) &
2944 BTRFS_EXTENDED_PROFILE_MASK;
2945
2946 if (bargs->profiles & chunk_type)
2947 return 0;
2948
2949 return 1;
2950 }
2951
2952 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
2953 struct btrfs_balance_args *bargs)
2954 {
2955 struct btrfs_block_group_cache *cache;
2956 u64 chunk_used, user_thresh;
2957 int ret = 1;
2958
2959 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2960 chunk_used = btrfs_block_group_used(&cache->item);
2961
2962 if (bargs->usage == 0)
2963 user_thresh = 1;
2964 else if (bargs->usage > 100)
2965 user_thresh = cache->key.offset;
2966 else
2967 user_thresh = div_factor_fine(cache->key.offset,
2968 bargs->usage);
2969
2970 if (chunk_used < user_thresh)
2971 ret = 0;
2972
2973 btrfs_put_block_group(cache);
2974 return ret;
2975 }
2976
2977 static int chunk_devid_filter(struct extent_buffer *leaf,
2978 struct btrfs_chunk *chunk,
2979 struct btrfs_balance_args *bargs)
2980 {
2981 struct btrfs_stripe *stripe;
2982 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2983 int i;
2984
2985 for (i = 0; i < num_stripes; i++) {
2986 stripe = btrfs_stripe_nr(chunk, i);
2987 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
2988 return 0;
2989 }
2990
2991 return 1;
2992 }
2993
2994 /* [pstart, pend) */
2995 static int chunk_drange_filter(struct extent_buffer *leaf,
2996 struct btrfs_chunk *chunk,
2997 u64 chunk_offset,
2998 struct btrfs_balance_args *bargs)
2999 {
3000 struct btrfs_stripe *stripe;
3001 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3002 u64 stripe_offset;
3003 u64 stripe_length;
3004 int factor;
3005 int i;
3006
3007 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3008 return 0;
3009
3010 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
3011 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
3012 factor = num_stripes / 2;
3013 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
3014 factor = num_stripes - 1;
3015 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
3016 factor = num_stripes - 2;
3017 } else {
3018 factor = num_stripes;
3019 }
3020
3021 for (i = 0; i < num_stripes; i++) {
3022 stripe = btrfs_stripe_nr(chunk, i);
3023 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3024 continue;
3025
3026 stripe_offset = btrfs_stripe_offset(leaf, stripe);
3027 stripe_length = btrfs_chunk_length(leaf, chunk);
3028 stripe_length = div_u64(stripe_length, factor);
3029
3030 if (stripe_offset < bargs->pend &&
3031 stripe_offset + stripe_length > bargs->pstart)
3032 return 0;
3033 }
3034
3035 return 1;
3036 }
3037
3038 /* [vstart, vend) */
3039 static int chunk_vrange_filter(struct extent_buffer *leaf,
3040 struct btrfs_chunk *chunk,
3041 u64 chunk_offset,
3042 struct btrfs_balance_args *bargs)
3043 {
3044 if (chunk_offset < bargs->vend &&
3045 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
3046 /* at least part of the chunk is inside this vrange */
3047 return 0;
3048
3049 return 1;
3050 }
3051
3052 static int chunk_soft_convert_filter(u64 chunk_type,
3053 struct btrfs_balance_args *bargs)
3054 {
3055 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
3056 return 0;
3057
3058 chunk_type = chunk_to_extended(chunk_type) &
3059 BTRFS_EXTENDED_PROFILE_MASK;
3060
3061 if (bargs->target == chunk_type)
3062 return 1;
3063
3064 return 0;
3065 }
3066
3067 static int should_balance_chunk(struct btrfs_root *root,
3068 struct extent_buffer *leaf,
3069 struct btrfs_chunk *chunk, u64 chunk_offset)
3070 {
3071 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
3072 struct btrfs_balance_args *bargs = NULL;
3073 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
3074
3075 /* type filter */
3076 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
3077 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
3078 return 0;
3079 }
3080
3081 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3082 bargs = &bctl->data;
3083 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3084 bargs = &bctl->sys;
3085 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3086 bargs = &bctl->meta;
3087
3088 /* profiles filter */
3089 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
3090 chunk_profiles_filter(chunk_type, bargs)) {
3091 return 0;
3092 }
3093
3094 /* usage filter */
3095 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
3096 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
3097 return 0;
3098 }
3099
3100 /* devid filter */
3101 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
3102 chunk_devid_filter(leaf, chunk, bargs)) {
3103 return 0;
3104 }
3105
3106 /* drange filter, makes sense only with devid filter */
3107 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
3108 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
3109 return 0;
3110 }
3111
3112 /* vrange filter */
3113 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
3114 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
3115 return 0;
3116 }
3117
3118 /* soft profile changing mode */
3119 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
3120 chunk_soft_convert_filter(chunk_type, bargs)) {
3121 return 0;
3122 }
3123
3124 /*
3125 * limited by count, must be the last filter
3126 */
3127 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
3128 if (bargs->limit == 0)
3129 return 0;
3130 else
3131 bargs->limit--;
3132 }
3133
3134 return 1;
3135 }
3136
3137 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
3138 {
3139 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3140 struct btrfs_root *chunk_root = fs_info->chunk_root;
3141 struct btrfs_root *dev_root = fs_info->dev_root;
3142 struct list_head *devices;
3143 struct btrfs_device *device;
3144 u64 old_size;
3145 u64 size_to_free;
3146 struct btrfs_chunk *chunk;
3147 struct btrfs_path *path;
3148 struct btrfs_key key;
3149 struct btrfs_key found_key;
3150 struct btrfs_trans_handle *trans;
3151 struct extent_buffer *leaf;
3152 int slot;
3153 int ret;
3154 int enospc_errors = 0;
3155 bool counting = true;
3156 u64 limit_data = bctl->data.limit;
3157 u64 limit_meta = bctl->meta.limit;
3158 u64 limit_sys = bctl->sys.limit;
3159
3160 /* step one make some room on all the devices */
3161 devices = &fs_info->fs_devices->devices;
3162 list_for_each_entry(device, devices, dev_list) {
3163 old_size = btrfs_device_get_total_bytes(device);
3164 size_to_free = div_factor(old_size, 1);
3165 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
3166 if (!device->writeable ||
3167 btrfs_device_get_total_bytes(device) -
3168 btrfs_device_get_bytes_used(device) > size_to_free ||
3169 device->is_tgtdev_for_dev_replace)
3170 continue;
3171
3172 ret = btrfs_shrink_device(device, old_size - size_to_free);
3173 if (ret == -ENOSPC)
3174 break;
3175 BUG_ON(ret);
3176
3177 trans = btrfs_start_transaction(dev_root, 0);
3178 BUG_ON(IS_ERR(trans));
3179
3180 ret = btrfs_grow_device(trans, device, old_size);
3181 BUG_ON(ret);
3182
3183 btrfs_end_transaction(trans, dev_root);
3184 }
3185
3186 /* step two, relocate all the chunks */
3187 path = btrfs_alloc_path();
3188 if (!path) {
3189 ret = -ENOMEM;
3190 goto error;
3191 }
3192
3193 /* zero out stat counters */
3194 spin_lock(&fs_info->balance_lock);
3195 memset(&bctl->stat, 0, sizeof(bctl->stat));
3196 spin_unlock(&fs_info->balance_lock);
3197 again:
3198 if (!counting) {
3199 bctl->data.limit = limit_data;
3200 bctl->meta.limit = limit_meta;
3201 bctl->sys.limit = limit_sys;
3202 }
3203 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3204 key.offset = (u64)-1;
3205 key.type = BTRFS_CHUNK_ITEM_KEY;
3206
3207 while (1) {
3208 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
3209 atomic_read(&fs_info->balance_cancel_req)) {
3210 ret = -ECANCELED;
3211 goto error;
3212 }
3213
3214 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3215 if (ret < 0)
3216 goto error;
3217
3218 /*
3219 * this shouldn't happen, it means the last relocate
3220 * failed
3221 */
3222 if (ret == 0)
3223 BUG(); /* FIXME break ? */
3224
3225 ret = btrfs_previous_item(chunk_root, path, 0,
3226 BTRFS_CHUNK_ITEM_KEY);
3227 if (ret) {
3228 ret = 0;
3229 break;
3230 }
3231
3232 leaf = path->nodes[0];
3233 slot = path->slots[0];
3234 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3235
3236 if (found_key.objectid != key.objectid)
3237 break;
3238
3239 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3240
3241 if (!counting) {
3242 spin_lock(&fs_info->balance_lock);
3243 bctl->stat.considered++;
3244 spin_unlock(&fs_info->balance_lock);
3245 }
3246
3247 ret = should_balance_chunk(chunk_root, leaf, chunk,
3248 found_key.offset);
3249 btrfs_release_path(path);
3250 if (!ret)
3251 goto loop;
3252
3253 if (counting) {
3254 spin_lock(&fs_info->balance_lock);
3255 bctl->stat.expected++;
3256 spin_unlock(&fs_info->balance_lock);
3257 goto loop;
3258 }
3259
3260 ret = btrfs_relocate_chunk(chunk_root,
3261 found_key.objectid,
3262 found_key.offset);
3263 if (ret && ret != -ENOSPC)
3264 goto error;
3265 if (ret == -ENOSPC) {
3266 enospc_errors++;
3267 } else {
3268 spin_lock(&fs_info->balance_lock);
3269 bctl->stat.completed++;
3270 spin_unlock(&fs_info->balance_lock);
3271 }
3272 loop:
3273 if (found_key.offset == 0)
3274 break;
3275 key.offset = found_key.offset - 1;
3276 }
3277
3278 if (counting) {
3279 btrfs_release_path(path);
3280 counting = false;
3281 goto again;
3282 }
3283 error:
3284 btrfs_free_path(path);
3285 if (enospc_errors) {
3286 btrfs_info(fs_info, "%d enospc errors during balance",
3287 enospc_errors);
3288 if (!ret)
3289 ret = -ENOSPC;
3290 }
3291
3292 return ret;
3293 }
3294
3295 /**
3296 * alloc_profile_is_valid - see if a given profile is valid and reduced
3297 * @flags: profile to validate
3298 * @extended: if true @flags is treated as an extended profile
3299 */
3300 static int alloc_profile_is_valid(u64 flags, int extended)
3301 {
3302 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
3303 BTRFS_BLOCK_GROUP_PROFILE_MASK);
3304
3305 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
3306
3307 /* 1) check that all other bits are zeroed */
3308 if (flags & ~mask)
3309 return 0;
3310
3311 /* 2) see if profile is reduced */
3312 if (flags == 0)
3313 return !extended; /* "0" is valid for usual profiles */
3314
3315 /* true if exactly one bit set */
3316 return (flags & (flags - 1)) == 0;
3317 }
3318
3319 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
3320 {
3321 /* cancel requested || normal exit path */
3322 return atomic_read(&fs_info->balance_cancel_req) ||
3323 (atomic_read(&fs_info->balance_pause_req) == 0 &&
3324 atomic_read(&fs_info->balance_cancel_req) == 0);
3325 }
3326
3327 static void __cancel_balance(struct btrfs_fs_info *fs_info)
3328 {
3329 int ret;
3330
3331 unset_balance_control(fs_info);
3332 ret = del_balance_item(fs_info->tree_root);
3333 if (ret)
3334 btrfs_std_error(fs_info, ret);
3335
3336 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3337 }
3338
3339 /*
3340 * Should be called with both balance and volume mutexes held
3341 */
3342 int btrfs_balance(struct btrfs_balance_control *bctl,
3343 struct btrfs_ioctl_balance_args *bargs)
3344 {
3345 struct btrfs_fs_info *fs_info = bctl->fs_info;
3346 u64 allowed;
3347 int mixed = 0;
3348 int ret;
3349 u64 num_devices;
3350 unsigned seq;
3351
3352 if (btrfs_fs_closing(fs_info) ||
3353 atomic_read(&fs_info->balance_pause_req) ||
3354 atomic_read(&fs_info->balance_cancel_req)) {
3355 ret = -EINVAL;
3356 goto out;
3357 }
3358
3359 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3360 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3361 mixed = 1;
3362
3363 /*
3364 * In case of mixed groups both data and meta should be picked,
3365 * and identical options should be given for both of them.
3366 */
3367 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3368 if (mixed && (bctl->flags & allowed)) {
3369 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3370 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3371 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3372 btrfs_err(fs_info, "with mixed groups data and "
3373 "metadata balance options must be the same");
3374 ret = -EINVAL;
3375 goto out;
3376 }
3377 }
3378
3379 num_devices = fs_info->fs_devices->num_devices;
3380 btrfs_dev_replace_lock(&fs_info->dev_replace);
3381 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3382 BUG_ON(num_devices < 1);
3383 num_devices--;
3384 }
3385 btrfs_dev_replace_unlock(&fs_info->dev_replace);
3386 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3387 if (num_devices == 1)
3388 allowed |= BTRFS_BLOCK_GROUP_DUP;
3389 else if (num_devices > 1)
3390 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3391 if (num_devices > 2)
3392 allowed |= BTRFS_BLOCK_GROUP_RAID5;
3393 if (num_devices > 3)
3394 allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
3395 BTRFS_BLOCK_GROUP_RAID6);
3396 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3397 (!alloc_profile_is_valid(bctl->data.target, 1) ||
3398 (bctl->data.target & ~allowed))) {
3399 btrfs_err(fs_info, "unable to start balance with target "
3400 "data profile %llu",
3401 bctl->data.target);
3402 ret = -EINVAL;
3403 goto out;
3404 }
3405 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3406 (!alloc_profile_is_valid(bctl->meta.target, 1) ||
3407 (bctl->meta.target & ~allowed))) {
3408 btrfs_err(fs_info,
3409 "unable to start balance with target metadata profile %llu",
3410 bctl->meta.target);
3411 ret = -EINVAL;
3412 goto out;
3413 }
3414 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3415 (!alloc_profile_is_valid(bctl->sys.target, 1) ||
3416 (bctl->sys.target & ~allowed))) {
3417 btrfs_err(fs_info,
3418 "unable to start balance with target system profile %llu",
3419 bctl->sys.target);
3420 ret = -EINVAL;
3421 goto out;
3422 }
3423
3424 /* allow dup'ed data chunks only in mixed mode */
3425 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3426 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
3427 btrfs_err(fs_info, "dup for data is not allowed");
3428 ret = -EINVAL;
3429 goto out;
3430 }
3431
3432 /* allow to reduce meta or sys integrity only if force set */
3433 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3434 BTRFS_BLOCK_GROUP_RAID10 |
3435 BTRFS_BLOCK_GROUP_RAID5 |
3436 BTRFS_BLOCK_GROUP_RAID6;
3437 do {
3438 seq = read_seqbegin(&fs_info->profiles_lock);
3439
3440 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3441 (fs_info->avail_system_alloc_bits & allowed) &&
3442 !(bctl->sys.target & allowed)) ||
3443 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3444 (fs_info->avail_metadata_alloc_bits & allowed) &&
3445 !(bctl->meta.target & allowed))) {
3446 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3447 btrfs_info(fs_info, "force reducing metadata integrity");
3448 } else {
3449 btrfs_err(fs_info, "balance will reduce metadata "
3450 "integrity, use force if you want this");
3451 ret = -EINVAL;
3452 goto out;
3453 }
3454 }
3455 } while (read_seqretry(&fs_info->profiles_lock, seq));
3456
3457 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3458 int num_tolerated_disk_barrier_failures;
3459 u64 target = bctl->sys.target;
3460
3461 num_tolerated_disk_barrier_failures =
3462 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3463 if (num_tolerated_disk_barrier_failures > 0 &&
3464 (target &
3465 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 |
3466 BTRFS_AVAIL_ALLOC_BIT_SINGLE)))
3467 num_tolerated_disk_barrier_failures = 0;
3468 else if (num_tolerated_disk_barrier_failures > 1 &&
3469 (target &
3470 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)))
3471 num_tolerated_disk_barrier_failures = 1;
3472
3473 fs_info->num_tolerated_disk_barrier_failures =
3474 num_tolerated_disk_barrier_failures;
3475 }
3476
3477 ret = insert_balance_item(fs_info->tree_root, bctl);
3478 if (ret && ret != -EEXIST)
3479 goto out;
3480
3481 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3482 BUG_ON(ret == -EEXIST);
3483 set_balance_control(bctl);
3484 } else {
3485 BUG_ON(ret != -EEXIST);
3486 spin_lock(&fs_info->balance_lock);
3487 update_balance_args(bctl);
3488 spin_unlock(&fs_info->balance_lock);
3489 }
3490
3491 atomic_inc(&fs_info->balance_running);
3492 mutex_unlock(&fs_info->balance_mutex);
3493
3494 ret = __btrfs_balance(fs_info);
3495
3496 mutex_lock(&fs_info->balance_mutex);
3497 atomic_dec(&fs_info->balance_running);
3498
3499 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3500 fs_info->num_tolerated_disk_barrier_failures =
3501 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3502 }
3503
3504 if (bargs) {
3505 memset(bargs, 0, sizeof(*bargs));
3506 update_ioctl_balance_args(fs_info, 0, bargs);
3507 }
3508
3509 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3510 balance_need_close(fs_info)) {
3511 __cancel_balance(fs_info);
3512 }
3513
3514 wake_up(&fs_info->balance_wait_q);
3515
3516 return ret;
3517 out:
3518 if (bctl->flags & BTRFS_BALANCE_RESUME)
3519 __cancel_balance(fs_info);
3520 else {
3521 kfree(bctl);
3522 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3523 }
3524 return ret;
3525 }
3526
3527 static int balance_kthread(void *data)
3528 {
3529 struct btrfs_fs_info *fs_info = data;
3530 int ret = 0;
3531
3532 mutex_lock(&fs_info->volume_mutex);
3533 mutex_lock(&fs_info->balance_mutex);
3534
3535 if (fs_info->balance_ctl) {
3536 btrfs_info(fs_info, "continuing balance");
3537 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3538 }
3539
3540 mutex_unlock(&fs_info->balance_mutex);
3541 mutex_unlock(&fs_info->volume_mutex);
3542
3543 return ret;
3544 }
3545
3546 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3547 {
3548 struct task_struct *tsk;
3549
3550 spin_lock(&fs_info->balance_lock);
3551 if (!fs_info->balance_ctl) {
3552 spin_unlock(&fs_info->balance_lock);
3553 return 0;
3554 }
3555 spin_unlock(&fs_info->balance_lock);
3556
3557 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3558 btrfs_info(fs_info, "force skipping balance");
3559 return 0;
3560 }
3561
3562 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3563 return PTR_ERR_OR_ZERO(tsk);
3564 }
3565
3566 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3567 {
3568 struct btrfs_balance_control *bctl;
3569 struct btrfs_balance_item *item;
3570 struct btrfs_disk_balance_args disk_bargs;
3571 struct btrfs_path *path;
3572 struct extent_buffer *leaf;
3573 struct btrfs_key key;
3574 int ret;
3575
3576 path = btrfs_alloc_path();
3577 if (!path)
3578 return -ENOMEM;
3579
3580 key.objectid = BTRFS_BALANCE_OBJECTID;
3581 key.type = BTRFS_BALANCE_ITEM_KEY;
3582 key.offset = 0;
3583
3584 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3585 if (ret < 0)
3586 goto out;
3587 if (ret > 0) { /* ret = -ENOENT; */
3588 ret = 0;
3589 goto out;
3590 }
3591
3592 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3593 if (!bctl) {
3594 ret = -ENOMEM;
3595 goto out;
3596 }
3597
3598 leaf = path->nodes[0];
3599 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3600
3601 bctl->fs_info = fs_info;
3602 bctl->flags = btrfs_balance_flags(leaf, item);
3603 bctl->flags |= BTRFS_BALANCE_RESUME;
3604
3605 btrfs_balance_data(leaf, item, &disk_bargs);
3606 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3607 btrfs_balance_meta(leaf, item, &disk_bargs);
3608 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3609 btrfs_balance_sys(leaf, item, &disk_bargs);
3610 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3611
3612 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3613
3614 mutex_lock(&fs_info->volume_mutex);
3615 mutex_lock(&fs_info->balance_mutex);
3616
3617 set_balance_control(bctl);
3618
3619 mutex_unlock(&fs_info->balance_mutex);
3620 mutex_unlock(&fs_info->volume_mutex);
3621 out:
3622 btrfs_free_path(path);
3623 return ret;
3624 }
3625
3626 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3627 {
3628 int ret = 0;
3629
3630 mutex_lock(&fs_info->balance_mutex);
3631 if (!fs_info->balance_ctl) {
3632 mutex_unlock(&fs_info->balance_mutex);
3633 return -ENOTCONN;
3634 }
3635
3636 if (atomic_read(&fs_info->balance_running)) {
3637 atomic_inc(&fs_info->balance_pause_req);
3638 mutex_unlock(&fs_info->balance_mutex);
3639
3640 wait_event(fs_info->balance_wait_q,
3641 atomic_read(&fs_info->balance_running) == 0);
3642
3643 mutex_lock(&fs_info->balance_mutex);
3644 /* we are good with balance_ctl ripped off from under us */
3645 BUG_ON(atomic_read(&fs_info->balance_running));
3646 atomic_dec(&fs_info->balance_pause_req);
3647 } else {
3648 ret = -ENOTCONN;
3649 }
3650
3651 mutex_unlock(&fs_info->balance_mutex);
3652 return ret;
3653 }
3654
3655 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3656 {
3657 if (fs_info->sb->s_flags & MS_RDONLY)
3658 return -EROFS;
3659
3660 mutex_lock(&fs_info->balance_mutex);
3661 if (!fs_info->balance_ctl) {
3662 mutex_unlock(&fs_info->balance_mutex);
3663 return -ENOTCONN;
3664 }
3665
3666 atomic_inc(&fs_info->balance_cancel_req);
3667 /*
3668 * if we are running just wait and return, balance item is
3669 * deleted in btrfs_balance in this case
3670 */
3671 if (atomic_read(&fs_info->balance_running)) {
3672 mutex_unlock(&fs_info->balance_mutex);
3673 wait_event(fs_info->balance_wait_q,
3674 atomic_read(&fs_info->balance_running) == 0);
3675 mutex_lock(&fs_info->balance_mutex);
3676 } else {
3677 /* __cancel_balance needs volume_mutex */
3678 mutex_unlock(&fs_info->balance_mutex);
3679 mutex_lock(&fs_info->volume_mutex);
3680 mutex_lock(&fs_info->balance_mutex);
3681
3682 if (fs_info->balance_ctl)
3683 __cancel_balance(fs_info);
3684
3685 mutex_unlock(&fs_info->volume_mutex);
3686 }
3687
3688 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
3689 atomic_dec(&fs_info->balance_cancel_req);
3690 mutex_unlock(&fs_info->balance_mutex);
3691 return 0;
3692 }
3693
3694 static int btrfs_uuid_scan_kthread(void *data)
3695 {
3696 struct btrfs_fs_info *fs_info = data;
3697 struct btrfs_root *root = fs_info->tree_root;
3698 struct btrfs_key key;
3699 struct btrfs_key max_key;
3700 struct btrfs_path *path = NULL;
3701 int ret = 0;
3702 struct extent_buffer *eb;
3703 int slot;
3704 struct btrfs_root_item root_item;
3705 u32 item_size;
3706 struct btrfs_trans_handle *trans = NULL;
3707
3708 path = btrfs_alloc_path();
3709 if (!path) {
3710 ret = -ENOMEM;
3711 goto out;
3712 }
3713
3714 key.objectid = 0;
3715 key.type = BTRFS_ROOT_ITEM_KEY;
3716 key.offset = 0;
3717
3718 max_key.objectid = (u64)-1;
3719 max_key.type = BTRFS_ROOT_ITEM_KEY;
3720 max_key.offset = (u64)-1;
3721
3722 while (1) {
3723 ret = btrfs_search_forward(root, &key, path, 0);
3724 if (ret) {
3725 if (ret > 0)
3726 ret = 0;
3727 break;
3728 }
3729
3730 if (key.type != BTRFS_ROOT_ITEM_KEY ||
3731 (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
3732 key.objectid != BTRFS_FS_TREE_OBJECTID) ||
3733 key.objectid > BTRFS_LAST_FREE_OBJECTID)
3734 goto skip;
3735
3736 eb = path->nodes[0];
3737 slot = path->slots[0];
3738 item_size = btrfs_item_size_nr(eb, slot);
3739 if (item_size < sizeof(root_item))
3740 goto skip;
3741
3742 read_extent_buffer(eb, &root_item,
3743 btrfs_item_ptr_offset(eb, slot),
3744 (int)sizeof(root_item));
3745 if (btrfs_root_refs(&root_item) == 0)
3746 goto skip;
3747
3748 if (!btrfs_is_empty_uuid(root_item.uuid) ||
3749 !btrfs_is_empty_uuid(root_item.received_uuid)) {
3750 if (trans)
3751 goto update_tree;
3752
3753 btrfs_release_path(path);
3754 /*
3755 * 1 - subvol uuid item
3756 * 1 - received_subvol uuid item
3757 */
3758 trans = btrfs_start_transaction(fs_info->uuid_root, 2);
3759 if (IS_ERR(trans)) {
3760 ret = PTR_ERR(trans);
3761 break;
3762 }
3763 continue;
3764 } else {
3765 goto skip;
3766 }
3767 update_tree:
3768 if (!btrfs_is_empty_uuid(root_item.uuid)) {
3769 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3770 root_item.uuid,
3771 BTRFS_UUID_KEY_SUBVOL,
3772 key.objectid);
3773 if (ret < 0) {
3774 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3775 ret);
3776 break;
3777 }
3778 }
3779
3780 if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
3781 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3782 root_item.received_uuid,
3783 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
3784 key.objectid);
3785 if (ret < 0) {
3786 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3787 ret);
3788 break;
3789 }
3790 }
3791
3792 skip:
3793 if (trans) {
3794 ret = btrfs_end_transaction(trans, fs_info->uuid_root);
3795 trans = NULL;
3796 if (ret)
3797 break;
3798 }
3799
3800 btrfs_release_path(path);
3801 if (key.offset < (u64)-1) {
3802 key.offset++;
3803 } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
3804 key.offset = 0;
3805 key.type = BTRFS_ROOT_ITEM_KEY;
3806 } else if (key.objectid < (u64)-1) {
3807 key.offset = 0;
3808 key.type = BTRFS_ROOT_ITEM_KEY;
3809 key.objectid++;
3810 } else {
3811 break;
3812 }
3813 cond_resched();
3814 }
3815
3816 out:
3817 btrfs_free_path(path);
3818 if (trans && !IS_ERR(trans))
3819 btrfs_end_transaction(trans, fs_info->uuid_root);
3820 if (ret)
3821 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
3822 else
3823 fs_info->update_uuid_tree_gen = 1;
3824 up(&fs_info->uuid_tree_rescan_sem);
3825 return 0;
3826 }
3827
3828 /*
3829 * Callback for btrfs_uuid_tree_iterate().
3830 * returns:
3831 * 0 check succeeded, the entry is not outdated.
3832 * < 0 if an error occured.
3833 * > 0 if the check failed, which means the caller shall remove the entry.
3834 */
3835 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
3836 u8 *uuid, u8 type, u64 subid)
3837 {
3838 struct btrfs_key key;
3839 int ret = 0;
3840 struct btrfs_root *subvol_root;
3841
3842 if (type != BTRFS_UUID_KEY_SUBVOL &&
3843 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
3844 goto out;
3845
3846 key.objectid = subid;
3847 key.type = BTRFS_ROOT_ITEM_KEY;
3848 key.offset = (u64)-1;
3849 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
3850 if (IS_ERR(subvol_root)) {
3851 ret = PTR_ERR(subvol_root);
3852 if (ret == -ENOENT)
3853 ret = 1;
3854 goto out;
3855 }
3856
3857 switch (type) {
3858 case BTRFS_UUID_KEY_SUBVOL:
3859 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
3860 ret = 1;
3861 break;
3862 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
3863 if (memcmp(uuid, subvol_root->root_item.received_uuid,
3864 BTRFS_UUID_SIZE))
3865 ret = 1;
3866 break;
3867 }
3868
3869 out:
3870 return ret;
3871 }
3872
3873 static int btrfs_uuid_rescan_kthread(void *data)
3874 {
3875 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
3876 int ret;
3877
3878 /*
3879 * 1st step is to iterate through the existing UUID tree and
3880 * to delete all entries that contain outdated data.
3881 * 2nd step is to add all missing entries to the UUID tree.
3882 */
3883 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
3884 if (ret < 0) {
3885 btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
3886 up(&fs_info->uuid_tree_rescan_sem);
3887 return ret;
3888 }
3889 return btrfs_uuid_scan_kthread(data);
3890 }
3891
3892 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
3893 {
3894 struct btrfs_trans_handle *trans;
3895 struct btrfs_root *tree_root = fs_info->tree_root;
3896 struct btrfs_root *uuid_root;
3897 struct task_struct *task;
3898 int ret;
3899
3900 /*
3901 * 1 - root node
3902 * 1 - root item
3903 */
3904 trans = btrfs_start_transaction(tree_root, 2);
3905 if (IS_ERR(trans))
3906 return PTR_ERR(trans);
3907
3908 uuid_root = btrfs_create_tree(trans, fs_info,
3909 BTRFS_UUID_TREE_OBJECTID);
3910 if (IS_ERR(uuid_root)) {
3911 btrfs_abort_transaction(trans, tree_root,
3912 PTR_ERR(uuid_root));
3913 return PTR_ERR(uuid_root);
3914 }
3915
3916 fs_info->uuid_root = uuid_root;
3917
3918 ret = btrfs_commit_transaction(trans, tree_root);
3919 if (ret)
3920 return ret;
3921
3922 down(&fs_info->uuid_tree_rescan_sem);
3923 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
3924 if (IS_ERR(task)) {
3925 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3926 btrfs_warn(fs_info, "failed to start uuid_scan task");
3927 up(&fs_info->uuid_tree_rescan_sem);
3928 return PTR_ERR(task);
3929 }
3930
3931 return 0;
3932 }
3933
3934 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
3935 {
3936 struct task_struct *task;
3937
3938 down(&fs_info->uuid_tree_rescan_sem);
3939 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
3940 if (IS_ERR(task)) {
3941 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3942 btrfs_warn(fs_info, "failed to start uuid_rescan task");
3943 up(&fs_info->uuid_tree_rescan_sem);
3944 return PTR_ERR(task);
3945 }
3946
3947 return 0;
3948 }
3949
3950 /*
3951 * shrinking a device means finding all of the device extents past
3952 * the new size, and then following the back refs to the chunks.
3953 * The chunk relocation code actually frees the device extent
3954 */
3955 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
3956 {
3957 struct btrfs_trans_handle *trans;
3958 struct btrfs_root *root = device->dev_root;
3959 struct btrfs_dev_extent *dev_extent = NULL;
3960 struct btrfs_path *path;
3961 u64 length;
3962 u64 chunk_objectid;
3963 u64 chunk_offset;
3964 int ret;
3965 int slot;
3966 int failed = 0;
3967 bool retried = false;
3968 struct extent_buffer *l;
3969 struct btrfs_key key;
3970 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3971 u64 old_total = btrfs_super_total_bytes(super_copy);
3972 u64 old_size = btrfs_device_get_total_bytes(device);
3973 u64 diff = old_size - new_size;
3974
3975 if (device->is_tgtdev_for_dev_replace)
3976 return -EINVAL;
3977
3978 path = btrfs_alloc_path();
3979 if (!path)
3980 return -ENOMEM;
3981
3982 path->reada = 2;
3983
3984 lock_chunks(root);
3985
3986 btrfs_device_set_total_bytes(device, new_size);
3987 if (device->writeable) {
3988 device->fs_devices->total_rw_bytes -= diff;
3989 spin_lock(&root->fs_info->free_chunk_lock);
3990 root->fs_info->free_chunk_space -= diff;
3991 spin_unlock(&root->fs_info->free_chunk_lock);
3992 }
3993 unlock_chunks(root);
3994
3995 again:
3996 key.objectid = device->devid;
3997 key.offset = (u64)-1;
3998 key.type = BTRFS_DEV_EXTENT_KEY;
3999
4000 do {
4001 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4002 if (ret < 0)
4003 goto done;
4004
4005 ret = btrfs_previous_item(root, path, 0, key.type);
4006 if (ret < 0)
4007 goto done;
4008 if (ret) {
4009 ret = 0;
4010 btrfs_release_path(path);
4011 break;
4012 }
4013
4014 l = path->nodes[0];
4015 slot = path->slots[0];
4016 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
4017
4018 if (key.objectid != device->devid) {
4019 btrfs_release_path(path);
4020 break;
4021 }
4022
4023 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
4024 length = btrfs_dev_extent_length(l, dev_extent);
4025
4026 if (key.offset + length <= new_size) {
4027 btrfs_release_path(path);
4028 break;
4029 }
4030
4031 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
4032 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
4033 btrfs_release_path(path);
4034
4035 ret = btrfs_relocate_chunk(root, chunk_objectid, chunk_offset);
4036 if (ret && ret != -ENOSPC)
4037 goto done;
4038 if (ret == -ENOSPC)
4039 failed++;
4040 } while (key.offset-- > 0);
4041
4042 if (failed && !retried) {
4043 failed = 0;
4044 retried = true;
4045 goto again;
4046 } else if (failed && retried) {
4047 ret = -ENOSPC;
4048 lock_chunks(root);
4049
4050 btrfs_device_set_total_bytes(device, old_size);
4051 if (device->writeable)
4052 device->fs_devices->total_rw_bytes += diff;
4053 spin_lock(&root->fs_info->free_chunk_lock);
4054 root->fs_info->free_chunk_space += diff;
4055 spin_unlock(&root->fs_info->free_chunk_lock);
4056 unlock_chunks(root);
4057 goto done;
4058 }
4059
4060 /* Shrinking succeeded, else we would be at "done". */
4061 trans = btrfs_start_transaction(root, 0);
4062 if (IS_ERR(trans)) {
4063 ret = PTR_ERR(trans);
4064 goto done;
4065 }
4066
4067 lock_chunks(root);
4068 btrfs_device_set_disk_total_bytes(device, new_size);
4069 if (list_empty(&device->resized_list))
4070 list_add_tail(&device->resized_list,
4071 &root->fs_info->fs_devices->resized_devices);
4072
4073 WARN_ON(diff > old_total);
4074 btrfs_set_super_total_bytes(super_copy, old_total - diff);
4075 unlock_chunks(root);
4076
4077 /* Now btrfs_update_device() will change the on-disk size. */
4078 ret = btrfs_update_device(trans, device);
4079 btrfs_end_transaction(trans, root);
4080 done:
4081 btrfs_free_path(path);
4082 return ret;
4083 }
4084
4085 static int btrfs_add_system_chunk(struct btrfs_root *root,
4086 struct btrfs_key *key,
4087 struct btrfs_chunk *chunk, int item_size)
4088 {
4089 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4090 struct btrfs_disk_key disk_key;
4091 u32 array_size;
4092 u8 *ptr;
4093
4094 lock_chunks(root);
4095 array_size = btrfs_super_sys_array_size(super_copy);
4096 if (array_size + item_size + sizeof(disk_key)
4097 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
4098 unlock_chunks(root);
4099 return -EFBIG;
4100 }
4101
4102 ptr = super_copy->sys_chunk_array + array_size;
4103 btrfs_cpu_key_to_disk(&disk_key, key);
4104 memcpy(ptr, &disk_key, sizeof(disk_key));
4105 ptr += sizeof(disk_key);
4106 memcpy(ptr, chunk, item_size);
4107 item_size += sizeof(disk_key);
4108 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
4109 unlock_chunks(root);
4110
4111 return 0;
4112 }
4113
4114 /*
4115 * sort the devices in descending order by max_avail, total_avail
4116 */
4117 static int btrfs_cmp_device_info(const void *a, const void *b)
4118 {
4119 const struct btrfs_device_info *di_a = a;
4120 const struct btrfs_device_info *di_b = b;
4121
4122 if (di_a->max_avail > di_b->max_avail)
4123 return -1;
4124 if (di_a->max_avail < di_b->max_avail)
4125 return 1;
4126 if (di_a->total_avail > di_b->total_avail)
4127 return -1;
4128 if (di_a->total_avail < di_b->total_avail)
4129 return 1;
4130 return 0;
4131 }
4132
4133 static const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
4134 [BTRFS_RAID_RAID10] = {
4135 .sub_stripes = 2,
4136 .dev_stripes = 1,
4137 .devs_max = 0, /* 0 == as many as possible */
4138 .devs_min = 4,
4139 .devs_increment = 2,
4140 .ncopies = 2,
4141 },
4142 [BTRFS_RAID_RAID1] = {
4143 .sub_stripes = 1,
4144 .dev_stripes = 1,
4145 .devs_max = 2,
4146 .devs_min = 2,
4147 .devs_increment = 2,
4148 .ncopies = 2,
4149 },
4150 [BTRFS_RAID_DUP] = {
4151 .sub_stripes = 1,
4152 .dev_stripes = 2,
4153 .devs_max = 1,
4154 .devs_min = 1,
4155 .devs_increment = 1,
4156 .ncopies = 2,
4157 },
4158 [BTRFS_RAID_RAID0] = {
4159 .sub_stripes = 1,
4160 .dev_stripes = 1,
4161 .devs_max = 0,
4162 .devs_min = 2,
4163 .devs_increment = 1,
4164 .ncopies = 1,
4165 },
4166 [BTRFS_RAID_SINGLE] = {
4167 .sub_stripes = 1,
4168 .dev_stripes = 1,
4169 .devs_max = 1,
4170 .devs_min = 1,
4171 .devs_increment = 1,
4172 .ncopies = 1,
4173 },
4174 [BTRFS_RAID_RAID5] = {
4175 .sub_stripes = 1,
4176 .dev_stripes = 1,
4177 .devs_max = 0,
4178 .devs_min = 2,
4179 .devs_increment = 1,
4180 .ncopies = 2,
4181 },
4182 [BTRFS_RAID_RAID6] = {
4183 .sub_stripes = 1,
4184 .dev_stripes = 1,
4185 .devs_max = 0,
4186 .devs_min = 3,
4187 .devs_increment = 1,
4188 .ncopies = 3,
4189 },
4190 };
4191
4192 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
4193 {
4194 /* TODO allow them to set a preferred stripe size */
4195 return 64 * 1024;
4196 }
4197
4198 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
4199 {
4200 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
4201 return;
4202
4203 btrfs_set_fs_incompat(info, RAID56);
4204 }
4205
4206 #define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \
4207 - sizeof(struct btrfs_item) \
4208 - sizeof(struct btrfs_chunk)) \
4209 / sizeof(struct btrfs_stripe) + 1)
4210
4211 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
4212 - 2 * sizeof(struct btrfs_disk_key) \
4213 - 2 * sizeof(struct btrfs_chunk)) \
4214 / sizeof(struct btrfs_stripe) + 1)
4215
4216 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4217 struct btrfs_root *extent_root, u64 start,
4218 u64 type)
4219 {
4220 struct btrfs_fs_info *info = extent_root->fs_info;
4221 struct btrfs_fs_devices *fs_devices = info->fs_devices;
4222 struct list_head *cur;
4223 struct map_lookup *map = NULL;
4224 struct extent_map_tree *em_tree;
4225 struct extent_map *em;
4226 struct btrfs_device_info *devices_info = NULL;
4227 u64 total_avail;
4228 int num_stripes; /* total number of stripes to allocate */
4229 int data_stripes; /* number of stripes that count for
4230 block group size */
4231 int sub_stripes; /* sub_stripes info for map */
4232 int dev_stripes; /* stripes per dev */
4233 int devs_max; /* max devs to use */
4234 int devs_min; /* min devs needed */
4235 int devs_increment; /* ndevs has to be a multiple of this */
4236 int ncopies; /* how many copies to data has */
4237 int ret;
4238 u64 max_stripe_size;
4239 u64 max_chunk_size;
4240 u64 stripe_size;
4241 u64 num_bytes;
4242 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
4243 int ndevs;
4244 int i;
4245 int j;
4246 int index;
4247
4248 BUG_ON(!alloc_profile_is_valid(type, 0));
4249
4250 if (list_empty(&fs_devices->alloc_list))
4251 return -ENOSPC;
4252
4253 index = __get_raid_index(type);
4254
4255 sub_stripes = btrfs_raid_array[index].sub_stripes;
4256 dev_stripes = btrfs_raid_array[index].dev_stripes;
4257 devs_max = btrfs_raid_array[index].devs_max;
4258 devs_min = btrfs_raid_array[index].devs_min;
4259 devs_increment = btrfs_raid_array[index].devs_increment;
4260 ncopies = btrfs_raid_array[index].ncopies;
4261
4262 if (type & BTRFS_BLOCK_GROUP_DATA) {
4263 max_stripe_size = 1024 * 1024 * 1024;
4264 max_chunk_size = 10 * max_stripe_size;
4265 if (!devs_max)
4266 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4267 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
4268 /* for larger filesystems, use larger metadata chunks */
4269 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
4270 max_stripe_size = 1024 * 1024 * 1024;
4271 else
4272 max_stripe_size = 256 * 1024 * 1024;
4273 max_chunk_size = max_stripe_size;
4274 if (!devs_max)
4275 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4276 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
4277 max_stripe_size = 32 * 1024 * 1024;
4278 max_chunk_size = 2 * max_stripe_size;
4279 if (!devs_max)
4280 devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
4281 } else {
4282 btrfs_err(info, "invalid chunk type 0x%llx requested",
4283 type);
4284 BUG_ON(1);
4285 }
4286
4287 /* we don't want a chunk larger than 10% of writeable space */
4288 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
4289 max_chunk_size);
4290
4291 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
4292 GFP_NOFS);
4293 if (!devices_info)
4294 return -ENOMEM;
4295
4296 cur = fs_devices->alloc_list.next;
4297
4298 /*
4299 * in the first pass through the devices list, we gather information
4300 * about the available holes on each device.
4301 */
4302 ndevs = 0;
4303 while (cur != &fs_devices->alloc_list) {
4304 struct btrfs_device *device;
4305 u64 max_avail;
4306 u64 dev_offset;
4307
4308 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
4309
4310 cur = cur->next;
4311
4312 if (!device->writeable) {
4313 WARN(1, KERN_ERR
4314 "BTRFS: read-only device in alloc_list\n");
4315 continue;
4316 }
4317
4318 if (!device->in_fs_metadata ||
4319 device->is_tgtdev_for_dev_replace)
4320 continue;
4321
4322 if (device->total_bytes > device->bytes_used)
4323 total_avail = device->total_bytes - device->bytes_used;
4324 else
4325 total_avail = 0;
4326
4327 /* If there is no space on this device, skip it. */
4328 if (total_avail == 0)
4329 continue;
4330
4331 ret = find_free_dev_extent(trans, device,
4332 max_stripe_size * dev_stripes,
4333 &dev_offset, &max_avail);
4334 if (ret && ret != -ENOSPC)
4335 goto error;
4336
4337 if (ret == 0)
4338 max_avail = max_stripe_size * dev_stripes;
4339
4340 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
4341 continue;
4342
4343 if (ndevs == fs_devices->rw_devices) {
4344 WARN(1, "%s: found more than %llu devices\n",
4345 __func__, fs_devices->rw_devices);
4346 break;
4347 }
4348 devices_info[ndevs].dev_offset = dev_offset;
4349 devices_info[ndevs].max_avail = max_avail;
4350 devices_info[ndevs].total_avail = total_avail;
4351 devices_info[ndevs].dev = device;
4352 ++ndevs;
4353 }
4354
4355 /*
4356 * now sort the devices by hole size / available space
4357 */
4358 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
4359 btrfs_cmp_device_info, NULL);
4360
4361 /* round down to number of usable stripes */
4362 ndevs -= ndevs % devs_increment;
4363
4364 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
4365 ret = -ENOSPC;
4366 goto error;
4367 }
4368
4369 if (devs_max && ndevs > devs_max)
4370 ndevs = devs_max;
4371 /*
4372 * the primary goal is to maximize the number of stripes, so use as many
4373 * devices as possible, even if the stripes are not maximum sized.
4374 */
4375 stripe_size = devices_info[ndevs-1].max_avail;
4376 num_stripes = ndevs * dev_stripes;
4377
4378 /*
4379 * this will have to be fixed for RAID1 and RAID10 over
4380 * more drives
4381 */
4382 data_stripes = num_stripes / ncopies;
4383
4384 if (type & BTRFS_BLOCK_GROUP_RAID5) {
4385 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
4386 btrfs_super_stripesize(info->super_copy));
4387 data_stripes = num_stripes - 1;
4388 }
4389 if (type & BTRFS_BLOCK_GROUP_RAID6) {
4390 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
4391 btrfs_super_stripesize(info->super_copy));
4392 data_stripes = num_stripes - 2;
4393 }
4394
4395 /*
4396 * Use the number of data stripes to figure out how big this chunk
4397 * is really going to be in terms of logical address space,
4398 * and compare that answer with the max chunk size
4399 */
4400 if (stripe_size * data_stripes > max_chunk_size) {
4401 u64 mask = (1ULL << 24) - 1;
4402
4403 stripe_size = div_u64(max_chunk_size, data_stripes);
4404
4405 /* bump the answer up to a 16MB boundary */
4406 stripe_size = (stripe_size + mask) & ~mask;
4407
4408 /* but don't go higher than the limits we found
4409 * while searching for free extents
4410 */
4411 if (stripe_size > devices_info[ndevs-1].max_avail)
4412 stripe_size = devices_info[ndevs-1].max_avail;
4413 }
4414
4415 stripe_size = div_u64(stripe_size, dev_stripes);
4416
4417 /* align to BTRFS_STRIPE_LEN */
4418 stripe_size = div_u64(stripe_size, raid_stripe_len);
4419 stripe_size *= raid_stripe_len;
4420
4421 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4422 if (!map) {
4423 ret = -ENOMEM;
4424 goto error;
4425 }
4426 map->num_stripes = num_stripes;
4427
4428 for (i = 0; i < ndevs; ++i) {
4429 for (j = 0; j < dev_stripes; ++j) {
4430 int s = i * dev_stripes + j;
4431 map->stripes[s].dev = devices_info[i].dev;
4432 map->stripes[s].physical = devices_info[i].dev_offset +
4433 j * stripe_size;
4434 }
4435 }
4436 map->sector_size = extent_root->sectorsize;
4437 map->stripe_len = raid_stripe_len;
4438 map->io_align = raid_stripe_len;
4439 map->io_width = raid_stripe_len;
4440 map->type = type;
4441 map->sub_stripes = sub_stripes;
4442
4443 num_bytes = stripe_size * data_stripes;
4444
4445 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
4446
4447 em = alloc_extent_map();
4448 if (!em) {
4449 kfree(map);
4450 ret = -ENOMEM;
4451 goto error;
4452 }
4453 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
4454 em->bdev = (struct block_device *)map;
4455 em->start = start;
4456 em->len = num_bytes;
4457 em->block_start = 0;
4458 em->block_len = em->len;
4459 em->orig_block_len = stripe_size;
4460
4461 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4462 write_lock(&em_tree->lock);
4463 ret = add_extent_mapping(em_tree, em, 0);
4464 if (!ret) {
4465 list_add_tail(&em->list, &trans->transaction->pending_chunks);
4466 atomic_inc(&em->refs);
4467 }
4468 write_unlock(&em_tree->lock);
4469 if (ret) {
4470 free_extent_map(em);
4471 goto error;
4472 }
4473
4474 ret = btrfs_make_block_group(trans, extent_root, 0, type,
4475 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4476 start, num_bytes);
4477 if (ret)
4478 goto error_del_extent;
4479
4480 for (i = 0; i < map->num_stripes; i++) {
4481 num_bytes = map->stripes[i].dev->bytes_used + stripe_size;
4482 btrfs_device_set_bytes_used(map->stripes[i].dev, num_bytes);
4483 }
4484
4485 spin_lock(&extent_root->fs_info->free_chunk_lock);
4486 extent_root->fs_info->free_chunk_space -= (stripe_size *
4487 map->num_stripes);
4488 spin_unlock(&extent_root->fs_info->free_chunk_lock);
4489
4490 free_extent_map(em);
4491 check_raid56_incompat_flag(extent_root->fs_info, type);
4492
4493 kfree(devices_info);
4494 return 0;
4495
4496 error_del_extent:
4497 write_lock(&em_tree->lock);
4498 remove_extent_mapping(em_tree, em);
4499 write_unlock(&em_tree->lock);
4500
4501 /* One for our allocation */
4502 free_extent_map(em);
4503 /* One for the tree reference */
4504 free_extent_map(em);
4505 /* One for the pending_chunks list reference */
4506 free_extent_map(em);
4507 error:
4508 kfree(devices_info);
4509 return ret;
4510 }
4511
4512 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
4513 struct btrfs_root *extent_root,
4514 u64 chunk_offset, u64 chunk_size)
4515 {
4516 struct btrfs_key key;
4517 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
4518 struct btrfs_device *device;
4519 struct btrfs_chunk *chunk;
4520 struct btrfs_stripe *stripe;
4521 struct extent_map_tree *em_tree;
4522 struct extent_map *em;
4523 struct map_lookup *map;
4524 size_t item_size;
4525 u64 dev_offset;
4526 u64 stripe_size;
4527 int i = 0;
4528 int ret;
4529
4530 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4531 read_lock(&em_tree->lock);
4532 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
4533 read_unlock(&em_tree->lock);
4534
4535 if (!em) {
4536 btrfs_crit(extent_root->fs_info, "unable to find logical "
4537 "%Lu len %Lu", chunk_offset, chunk_size);
4538 return -EINVAL;
4539 }
4540
4541 if (em->start != chunk_offset || em->len != chunk_size) {
4542 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted"
4543 " %Lu-%Lu, found %Lu-%Lu", chunk_offset,
4544 chunk_size, em->start, em->len);
4545 free_extent_map(em);
4546 return -EINVAL;
4547 }
4548
4549 map = (struct map_lookup *)em->bdev;
4550 item_size = btrfs_chunk_item_size(map->num_stripes);
4551 stripe_size = em->orig_block_len;
4552
4553 chunk = kzalloc(item_size, GFP_NOFS);
4554 if (!chunk) {
4555 ret = -ENOMEM;
4556 goto out;
4557 }
4558
4559 for (i = 0; i < map->num_stripes; i++) {
4560 device = map->stripes[i].dev;
4561 dev_offset = map->stripes[i].physical;
4562
4563 ret = btrfs_update_device(trans, device);
4564 if (ret)
4565 goto out;
4566 ret = btrfs_alloc_dev_extent(trans, device,
4567 chunk_root->root_key.objectid,
4568 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4569 chunk_offset, dev_offset,
4570 stripe_size);
4571 if (ret)
4572 goto out;
4573 }
4574
4575 stripe = &chunk->stripe;
4576 for (i = 0; i < map->num_stripes; i++) {
4577 device = map->stripes[i].dev;
4578 dev_offset = map->stripes[i].physical;
4579
4580 btrfs_set_stack_stripe_devid(stripe, device->devid);
4581 btrfs_set_stack_stripe_offset(stripe, dev_offset);
4582 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
4583 stripe++;
4584 }
4585
4586 btrfs_set_stack_chunk_length(chunk, chunk_size);
4587 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
4588 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
4589 btrfs_set_stack_chunk_type(chunk, map->type);
4590 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
4591 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
4592 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
4593 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
4594 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
4595
4596 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4597 key.type = BTRFS_CHUNK_ITEM_KEY;
4598 key.offset = chunk_offset;
4599
4600 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
4601 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
4602 /*
4603 * TODO: Cleanup of inserted chunk root in case of
4604 * failure.
4605 */
4606 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
4607 item_size);
4608 }
4609
4610 out:
4611 kfree(chunk);
4612 free_extent_map(em);
4613 return ret;
4614 }
4615
4616 /*
4617 * Chunk allocation falls into two parts. The first part does works
4618 * that make the new allocated chunk useable, but not do any operation
4619 * that modifies the chunk tree. The second part does the works that
4620 * require modifying the chunk tree. This division is important for the
4621 * bootstrap process of adding storage to a seed btrfs.
4622 */
4623 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4624 struct btrfs_root *extent_root, u64 type)
4625 {
4626 u64 chunk_offset;
4627
4628 ASSERT(mutex_is_locked(&extent_root->fs_info->chunk_mutex));
4629 chunk_offset = find_next_chunk(extent_root->fs_info);
4630 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type);
4631 }
4632
4633 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
4634 struct btrfs_root *root,
4635 struct btrfs_device *device)
4636 {
4637 u64 chunk_offset;
4638 u64 sys_chunk_offset;
4639 u64 alloc_profile;
4640 struct btrfs_fs_info *fs_info = root->fs_info;
4641 struct btrfs_root *extent_root = fs_info->extent_root;
4642 int ret;
4643
4644 chunk_offset = find_next_chunk(fs_info);
4645 alloc_profile = btrfs_get_alloc_profile(extent_root, 0);
4646 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset,
4647 alloc_profile);
4648 if (ret)
4649 return ret;
4650
4651 sys_chunk_offset = find_next_chunk(root->fs_info);
4652 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
4653 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset,
4654 alloc_profile);
4655 return ret;
4656 }
4657
4658 static inline int btrfs_chunk_max_errors(struct map_lookup *map)
4659 {
4660 int max_errors;
4661
4662 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
4663 BTRFS_BLOCK_GROUP_RAID10 |
4664 BTRFS_BLOCK_GROUP_RAID5 |
4665 BTRFS_BLOCK_GROUP_DUP)) {
4666 max_errors = 1;
4667 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
4668 max_errors = 2;
4669 } else {
4670 max_errors = 0;
4671 }
4672
4673 return max_errors;
4674 }
4675
4676 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
4677 {
4678 struct extent_map *em;
4679 struct map_lookup *map;
4680 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4681 int readonly = 0;
4682 int miss_ndevs = 0;
4683 int i;
4684
4685 read_lock(&map_tree->map_tree.lock);
4686 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
4687 read_unlock(&map_tree->map_tree.lock);
4688 if (!em)
4689 return 1;
4690
4691 map = (struct map_lookup *)em->bdev;
4692 for (i = 0; i < map->num_stripes; i++) {
4693 if (map->stripes[i].dev->missing) {
4694 miss_ndevs++;
4695 continue;
4696 }
4697
4698 if (!map->stripes[i].dev->writeable) {
4699 readonly = 1;
4700 goto end;
4701 }
4702 }
4703
4704 /*
4705 * If the number of missing devices is larger than max errors,
4706 * we can not write the data into that chunk successfully, so
4707 * set it readonly.
4708 */
4709 if (miss_ndevs > btrfs_chunk_max_errors(map))
4710 readonly = 1;
4711 end:
4712 free_extent_map(em);
4713 return readonly;
4714 }
4715
4716 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
4717 {
4718 extent_map_tree_init(&tree->map_tree);
4719 }
4720
4721 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
4722 {
4723 struct extent_map *em;
4724
4725 while (1) {
4726 write_lock(&tree->map_tree.lock);
4727 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
4728 if (em)
4729 remove_extent_mapping(&tree->map_tree, em);
4730 write_unlock(&tree->map_tree.lock);
4731 if (!em)
4732 break;
4733 /* once for us */
4734 free_extent_map(em);
4735 /* once for the tree */
4736 free_extent_map(em);
4737 }
4738 }
4739
4740 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
4741 {
4742 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4743 struct extent_map *em;
4744 struct map_lookup *map;
4745 struct extent_map_tree *em_tree = &map_tree->map_tree;
4746 int ret;
4747
4748 read_lock(&em_tree->lock);
4749 em = lookup_extent_mapping(em_tree, logical, len);
4750 read_unlock(&em_tree->lock);
4751
4752 /*
4753 * We could return errors for these cases, but that could get ugly and
4754 * we'd probably do the same thing which is just not do anything else
4755 * and exit, so return 1 so the callers don't try to use other copies.
4756 */
4757 if (!em) {
4758 btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
4759 logical+len);
4760 return 1;
4761 }
4762
4763 if (em->start > logical || em->start + em->len < logical) {
4764 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got "
4765 "%Lu-%Lu", logical, logical+len, em->start,
4766 em->start + em->len);
4767 free_extent_map(em);
4768 return 1;
4769 }
4770
4771 map = (struct map_lookup *)em->bdev;
4772 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
4773 ret = map->num_stripes;
4774 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
4775 ret = map->sub_stripes;
4776 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
4777 ret = 2;
4778 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
4779 ret = 3;
4780 else
4781 ret = 1;
4782 free_extent_map(em);
4783
4784 btrfs_dev_replace_lock(&fs_info->dev_replace);
4785 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
4786 ret++;
4787 btrfs_dev_replace_unlock(&fs_info->dev_replace);
4788
4789 return ret;
4790 }
4791
4792 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
4793 struct btrfs_mapping_tree *map_tree,
4794 u64 logical)
4795 {
4796 struct extent_map *em;
4797 struct map_lookup *map;
4798 struct extent_map_tree *em_tree = &map_tree->map_tree;
4799 unsigned long len = root->sectorsize;
4800
4801 read_lock(&em_tree->lock);
4802 em = lookup_extent_mapping(em_tree, logical, len);
4803 read_unlock(&em_tree->lock);
4804 BUG_ON(!em);
4805
4806 BUG_ON(em->start > logical || em->start + em->len < logical);
4807 map = (struct map_lookup *)em->bdev;
4808 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
4809 len = map->stripe_len * nr_data_stripes(map);
4810 free_extent_map(em);
4811 return len;
4812 }
4813
4814 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
4815 u64 logical, u64 len, int mirror_num)
4816 {
4817 struct extent_map *em;
4818 struct map_lookup *map;
4819 struct extent_map_tree *em_tree = &map_tree->map_tree;
4820 int ret = 0;
4821
4822 read_lock(&em_tree->lock);
4823 em = lookup_extent_mapping(em_tree, logical, len);
4824 read_unlock(&em_tree->lock);
4825 BUG_ON(!em);
4826
4827 BUG_ON(em->start > logical || em->start + em->len < logical);
4828 map = (struct map_lookup *)em->bdev;
4829 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
4830 ret = 1;
4831 free_extent_map(em);
4832 return ret;
4833 }
4834
4835 static int find_live_mirror(struct btrfs_fs_info *fs_info,
4836 struct map_lookup *map, int first, int num,
4837 int optimal, int dev_replace_is_ongoing)
4838 {
4839 int i;
4840 int tolerance;
4841 struct btrfs_device *srcdev;
4842
4843 if (dev_replace_is_ongoing &&
4844 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
4845 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
4846 srcdev = fs_info->dev_replace.srcdev;
4847 else
4848 srcdev = NULL;
4849
4850 /*
4851 * try to avoid the drive that is the source drive for a
4852 * dev-replace procedure, only choose it if no other non-missing
4853 * mirror is available
4854 */
4855 for (tolerance = 0; tolerance < 2; tolerance++) {
4856 if (map->stripes[optimal].dev->bdev &&
4857 (tolerance || map->stripes[optimal].dev != srcdev))
4858 return optimal;
4859 for (i = first; i < first + num; i++) {
4860 if (map->stripes[i].dev->bdev &&
4861 (tolerance || map->stripes[i].dev != srcdev))
4862 return i;
4863 }
4864 }
4865
4866 /* we couldn't find one that doesn't fail. Just return something
4867 * and the io error handling code will clean up eventually
4868 */
4869 return optimal;
4870 }
4871
4872 static inline int parity_smaller(u64 a, u64 b)
4873 {
4874 return a > b;
4875 }
4876
4877 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
4878 static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes)
4879 {
4880 struct btrfs_bio_stripe s;
4881 int i;
4882 u64 l;
4883 int again = 1;
4884
4885 while (again) {
4886 again = 0;
4887 for (i = 0; i < num_stripes - 1; i++) {
4888 if (parity_smaller(bbio->raid_map[i],
4889 bbio->raid_map[i+1])) {
4890 s = bbio->stripes[i];
4891 l = bbio->raid_map[i];
4892 bbio->stripes[i] = bbio->stripes[i+1];
4893 bbio->raid_map[i] = bbio->raid_map[i+1];
4894 bbio->stripes[i+1] = s;
4895 bbio->raid_map[i+1] = l;
4896
4897 again = 1;
4898 }
4899 }
4900 }
4901 }
4902
4903 static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
4904 {
4905 struct btrfs_bio *bbio = kzalloc(
4906 /* the size of the btrfs_bio */
4907 sizeof(struct btrfs_bio) +
4908 /* plus the variable array for the stripes */
4909 sizeof(struct btrfs_bio_stripe) * (total_stripes) +
4910 /* plus the variable array for the tgt dev */
4911 sizeof(int) * (real_stripes) +
4912 /*
4913 * plus the raid_map, which includes both the tgt dev
4914 * and the stripes
4915 */
4916 sizeof(u64) * (total_stripes),
4917 GFP_NOFS);
4918 if (!bbio)
4919 return NULL;
4920
4921 atomic_set(&bbio->error, 0);
4922 atomic_set(&bbio->refs, 1);
4923
4924 return bbio;
4925 }
4926
4927 void btrfs_get_bbio(struct btrfs_bio *bbio)
4928 {
4929 WARN_ON(!atomic_read(&bbio->refs));
4930 atomic_inc(&bbio->refs);
4931 }
4932
4933 void btrfs_put_bbio(struct btrfs_bio *bbio)
4934 {
4935 if (!bbio)
4936 return;
4937 if (atomic_dec_and_test(&bbio->refs))
4938 kfree(bbio);
4939 }
4940
4941 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
4942 u64 logical, u64 *length,
4943 struct btrfs_bio **bbio_ret,
4944 int mirror_num, int need_raid_map)
4945 {
4946 struct extent_map *em;
4947 struct map_lookup *map;
4948 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4949 struct extent_map_tree *em_tree = &map_tree->map_tree;
4950 u64 offset;
4951 u64 stripe_offset;
4952 u64 stripe_end_offset;
4953 u64 stripe_nr;
4954 u64 stripe_nr_orig;
4955 u64 stripe_nr_end;
4956 u64 stripe_len;
4957 u32 stripe_index;
4958 int i;
4959 int ret = 0;
4960 int num_stripes;
4961 int max_errors = 0;
4962 int tgtdev_indexes = 0;
4963 struct btrfs_bio *bbio = NULL;
4964 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
4965 int dev_replace_is_ongoing = 0;
4966 int num_alloc_stripes;
4967 int patch_the_first_stripe_for_dev_replace = 0;
4968 u64 physical_to_patch_in_first_stripe = 0;
4969 u64 raid56_full_stripe_start = (u64)-1;
4970
4971 read_lock(&em_tree->lock);
4972 em = lookup_extent_mapping(em_tree, logical, *length);
4973 read_unlock(&em_tree->lock);
4974
4975 if (!em) {
4976 btrfs_crit(fs_info, "unable to find logical %llu len %llu",
4977 logical, *length);
4978 return -EINVAL;
4979 }
4980
4981 if (em->start > logical || em->start + em->len < logical) {
4982 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, "
4983 "found %Lu-%Lu", logical, em->start,
4984 em->start + em->len);
4985 free_extent_map(em);
4986 return -EINVAL;
4987 }
4988
4989 map = (struct map_lookup *)em->bdev;
4990 offset = logical - em->start;
4991
4992 stripe_len = map->stripe_len;
4993 stripe_nr = offset;
4994 /*
4995 * stripe_nr counts the total number of stripes we have to stride
4996 * to get to this block
4997 */
4998 stripe_nr = div64_u64(stripe_nr, stripe_len);
4999
5000 stripe_offset = stripe_nr * stripe_len;
5001 BUG_ON(offset < stripe_offset);
5002
5003 /* stripe_offset is the offset of this block in its stripe*/
5004 stripe_offset = offset - stripe_offset;
5005
5006 /* if we're here for raid56, we need to know the stripe aligned start */
5007 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5008 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
5009 raid56_full_stripe_start = offset;
5010
5011 /* allow a write of a full stripe, but make sure we don't
5012 * allow straddling of stripes
5013 */
5014 raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
5015 full_stripe_len);
5016 raid56_full_stripe_start *= full_stripe_len;
5017 }
5018
5019 if (rw & REQ_DISCARD) {
5020 /* we don't discard raid56 yet */
5021 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5022 ret = -EOPNOTSUPP;
5023 goto out;
5024 }
5025 *length = min_t(u64, em->len - offset, *length);
5026 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
5027 u64 max_len;
5028 /* For writes to RAID[56], allow a full stripeset across all disks.
5029 For other RAID types and for RAID[56] reads, just allow a single
5030 stripe (on a single disk). */
5031 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
5032 (rw & REQ_WRITE)) {
5033 max_len = stripe_len * nr_data_stripes(map) -
5034 (offset - raid56_full_stripe_start);
5035 } else {
5036 /* we limit the length of each bio to what fits in a stripe */
5037 max_len = stripe_len - stripe_offset;
5038 }
5039 *length = min_t(u64, em->len - offset, max_len);
5040 } else {
5041 *length = em->len - offset;
5042 }
5043
5044 /* This is for when we're called from btrfs_merge_bio_hook() and all
5045 it cares about is the length */
5046 if (!bbio_ret)
5047 goto out;
5048
5049 btrfs_dev_replace_lock(dev_replace);
5050 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
5051 if (!dev_replace_is_ongoing)
5052 btrfs_dev_replace_unlock(dev_replace);
5053
5054 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
5055 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
5056 dev_replace->tgtdev != NULL) {
5057 /*
5058 * in dev-replace case, for repair case (that's the only
5059 * case where the mirror is selected explicitly when
5060 * calling btrfs_map_block), blocks left of the left cursor
5061 * can also be read from the target drive.
5062 * For REQ_GET_READ_MIRRORS, the target drive is added as
5063 * the last one to the array of stripes. For READ, it also
5064 * needs to be supported using the same mirror number.
5065 * If the requested block is not left of the left cursor,
5066 * EIO is returned. This can happen because btrfs_num_copies()
5067 * returns one more in the dev-replace case.
5068 */
5069 u64 tmp_length = *length;
5070 struct btrfs_bio *tmp_bbio = NULL;
5071 int tmp_num_stripes;
5072 u64 srcdev_devid = dev_replace->srcdev->devid;
5073 int index_srcdev = 0;
5074 int found = 0;
5075 u64 physical_of_found = 0;
5076
5077 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
5078 logical, &tmp_length, &tmp_bbio, 0, 0);
5079 if (ret) {
5080 WARN_ON(tmp_bbio != NULL);
5081 goto out;
5082 }
5083
5084 tmp_num_stripes = tmp_bbio->num_stripes;
5085 if (mirror_num > tmp_num_stripes) {
5086 /*
5087 * REQ_GET_READ_MIRRORS does not contain this
5088 * mirror, that means that the requested area
5089 * is not left of the left cursor
5090 */
5091 ret = -EIO;
5092 btrfs_put_bbio(tmp_bbio);
5093 goto out;
5094 }
5095
5096 /*
5097 * process the rest of the function using the mirror_num
5098 * of the source drive. Therefore look it up first.
5099 * At the end, patch the device pointer to the one of the
5100 * target drive.
5101 */
5102 for (i = 0; i < tmp_num_stripes; i++) {
5103 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) {
5104 /*
5105 * In case of DUP, in order to keep it
5106 * simple, only add the mirror with the
5107 * lowest physical address
5108 */
5109 if (found &&
5110 physical_of_found <=
5111 tmp_bbio->stripes[i].physical)
5112 continue;
5113 index_srcdev = i;
5114 found = 1;
5115 physical_of_found =
5116 tmp_bbio->stripes[i].physical;
5117 }
5118 }
5119
5120 if (found) {
5121 mirror_num = index_srcdev + 1;
5122 patch_the_first_stripe_for_dev_replace = 1;
5123 physical_to_patch_in_first_stripe = physical_of_found;
5124 } else {
5125 WARN_ON(1);
5126 ret = -EIO;
5127 btrfs_put_bbio(tmp_bbio);
5128 goto out;
5129 }
5130
5131 btrfs_put_bbio(tmp_bbio);
5132 } else if (mirror_num > map->num_stripes) {
5133 mirror_num = 0;
5134 }
5135
5136 num_stripes = 1;
5137 stripe_index = 0;
5138 stripe_nr_orig = stripe_nr;
5139 stripe_nr_end = ALIGN(offset + *length, map->stripe_len);
5140 stripe_nr_end = div_u64(stripe_nr_end, map->stripe_len);
5141 stripe_end_offset = stripe_nr_end * map->stripe_len -
5142 (offset + *length);
5143
5144 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5145 if (rw & REQ_DISCARD)
5146 num_stripes = min_t(u64, map->num_stripes,
5147 stripe_nr_end - stripe_nr_orig);
5148 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5149 &stripe_index);
5150 if (!(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)))
5151 mirror_num = 1;
5152 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
5153 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
5154 num_stripes = map->num_stripes;
5155 else if (mirror_num)
5156 stripe_index = mirror_num - 1;
5157 else {
5158 stripe_index = find_live_mirror(fs_info, map, 0,
5159 map->num_stripes,
5160 current->pid % map->num_stripes,
5161 dev_replace_is_ongoing);
5162 mirror_num = stripe_index + 1;
5163 }
5164
5165 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
5166 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
5167 num_stripes = map->num_stripes;
5168 } else if (mirror_num) {
5169 stripe_index = mirror_num - 1;
5170 } else {
5171 mirror_num = 1;
5172 }
5173
5174 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5175 u32 factor = map->num_stripes / map->sub_stripes;
5176
5177 stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
5178 stripe_index *= map->sub_stripes;
5179
5180 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5181 num_stripes = map->sub_stripes;
5182 else if (rw & REQ_DISCARD)
5183 num_stripes = min_t(u64, map->sub_stripes *
5184 (stripe_nr_end - stripe_nr_orig),
5185 map->num_stripes);
5186 else if (mirror_num)
5187 stripe_index += mirror_num - 1;
5188 else {
5189 int old_stripe_index = stripe_index;
5190 stripe_index = find_live_mirror(fs_info, map,
5191 stripe_index,
5192 map->sub_stripes, stripe_index +
5193 current->pid % map->sub_stripes,
5194 dev_replace_is_ongoing);
5195 mirror_num = stripe_index - old_stripe_index + 1;
5196 }
5197
5198 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5199 if (need_raid_map &&
5200 ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5201 mirror_num > 1)) {
5202 /* push stripe_nr back to the start of the full stripe */
5203 stripe_nr = div_u64(raid56_full_stripe_start,
5204 stripe_len * nr_data_stripes(map));
5205
5206 /* RAID[56] write or recovery. Return all stripes */
5207 num_stripes = map->num_stripes;
5208 max_errors = nr_parity_stripes(map);
5209
5210 *length = map->stripe_len;
5211 stripe_index = 0;
5212 stripe_offset = 0;
5213 } else {
5214 /*
5215 * Mirror #0 or #1 means the original data block.
5216 * Mirror #2 is RAID5 parity block.
5217 * Mirror #3 is RAID6 Q block.
5218 */
5219 stripe_nr = div_u64_rem(stripe_nr,
5220 nr_data_stripes(map), &stripe_index);
5221 if (mirror_num > 1)
5222 stripe_index = nr_data_stripes(map) +
5223 mirror_num - 2;
5224
5225 /* We distribute the parity blocks across stripes */
5226 div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
5227 &stripe_index);
5228 if (!(rw & (REQ_WRITE | REQ_DISCARD |
5229 REQ_GET_READ_MIRRORS)) && mirror_num <= 1)
5230 mirror_num = 1;
5231 }
5232 } else {
5233 /*
5234 * after this, stripe_nr is the number of stripes on this
5235 * device we have to walk to find the data, and stripe_index is
5236 * the number of our device in the stripe array
5237 */
5238 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5239 &stripe_index);
5240 mirror_num = stripe_index + 1;
5241 }
5242 BUG_ON(stripe_index >= map->num_stripes);
5243
5244 num_alloc_stripes = num_stripes;
5245 if (dev_replace_is_ongoing) {
5246 if (rw & (REQ_WRITE | REQ_DISCARD))
5247 num_alloc_stripes <<= 1;
5248 if (rw & REQ_GET_READ_MIRRORS)
5249 num_alloc_stripes++;
5250 tgtdev_indexes = num_stripes;
5251 }
5252
5253 bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes);
5254 if (!bbio) {
5255 ret = -ENOMEM;
5256 goto out;
5257 }
5258 if (dev_replace_is_ongoing)
5259 bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes);
5260
5261 /* build raid_map */
5262 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
5263 need_raid_map && ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5264 mirror_num > 1)) {
5265 u64 tmp;
5266 unsigned rot;
5267
5268 bbio->raid_map = (u64 *)((void *)bbio->stripes +
5269 sizeof(struct btrfs_bio_stripe) *
5270 num_alloc_stripes +
5271 sizeof(int) * tgtdev_indexes);
5272
5273 /* Work out the disk rotation on this stripe-set */
5274 div_u64_rem(stripe_nr, num_stripes, &rot);
5275
5276 /* Fill in the logical address of each stripe */
5277 tmp = stripe_nr * nr_data_stripes(map);
5278 for (i = 0; i < nr_data_stripes(map); i++)
5279 bbio->raid_map[(i+rot) % num_stripes] =
5280 em->start + (tmp + i) * map->stripe_len;
5281
5282 bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
5283 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5284 bbio->raid_map[(i+rot+1) % num_stripes] =
5285 RAID6_Q_STRIPE;
5286 }
5287
5288 if (rw & REQ_DISCARD) {
5289 u32 factor = 0;
5290 u32 sub_stripes = 0;
5291 u64 stripes_per_dev = 0;
5292 u32 remaining_stripes = 0;
5293 u32 last_stripe = 0;
5294
5295 if (map->type &
5296 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
5297 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5298 sub_stripes = 1;
5299 else
5300 sub_stripes = map->sub_stripes;
5301
5302 factor = map->num_stripes / sub_stripes;
5303 stripes_per_dev = div_u64_rem(stripe_nr_end -
5304 stripe_nr_orig,
5305 factor,
5306 &remaining_stripes);
5307 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
5308 last_stripe *= sub_stripes;
5309 }
5310
5311 for (i = 0; i < num_stripes; i++) {
5312 bbio->stripes[i].physical =
5313 map->stripes[stripe_index].physical +
5314 stripe_offset + stripe_nr * map->stripe_len;
5315 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
5316
5317 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
5318 BTRFS_BLOCK_GROUP_RAID10)) {
5319 bbio->stripes[i].length = stripes_per_dev *
5320 map->stripe_len;
5321
5322 if (i / sub_stripes < remaining_stripes)
5323 bbio->stripes[i].length +=
5324 map->stripe_len;
5325
5326 /*
5327 * Special for the first stripe and
5328 * the last stripe:
5329 *
5330 * |-------|...|-------|
5331 * |----------|
5332 * off end_off
5333 */
5334 if (i < sub_stripes)
5335 bbio->stripes[i].length -=
5336 stripe_offset;
5337
5338 if (stripe_index >= last_stripe &&
5339 stripe_index <= (last_stripe +
5340 sub_stripes - 1))
5341 bbio->stripes[i].length -=
5342 stripe_end_offset;
5343
5344 if (i == sub_stripes - 1)
5345 stripe_offset = 0;
5346 } else
5347 bbio->stripes[i].length = *length;
5348
5349 stripe_index++;
5350 if (stripe_index == map->num_stripes) {
5351 /* This could only happen for RAID0/10 */
5352 stripe_index = 0;
5353 stripe_nr++;
5354 }
5355 }
5356 } else {
5357 for (i = 0; i < num_stripes; i++) {
5358 bbio->stripes[i].physical =
5359 map->stripes[stripe_index].physical +
5360 stripe_offset +
5361 stripe_nr * map->stripe_len;
5362 bbio->stripes[i].dev =
5363 map->stripes[stripe_index].dev;
5364 stripe_index++;
5365 }
5366 }
5367
5368 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5369 max_errors = btrfs_chunk_max_errors(map);
5370
5371 if (bbio->raid_map)
5372 sort_parity_stripes(bbio, num_stripes);
5373
5374 tgtdev_indexes = 0;
5375 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
5376 dev_replace->tgtdev != NULL) {
5377 int index_where_to_add;
5378 u64 srcdev_devid = dev_replace->srcdev->devid;
5379
5380 /*
5381 * duplicate the write operations while the dev replace
5382 * procedure is running. Since the copying of the old disk
5383 * to the new disk takes place at run time while the
5384 * filesystem is mounted writable, the regular write
5385 * operations to the old disk have to be duplicated to go
5386 * to the new disk as well.
5387 * Note that device->missing is handled by the caller, and
5388 * that the write to the old disk is already set up in the
5389 * stripes array.
5390 */
5391 index_where_to_add = num_stripes;
5392 for (i = 0; i < num_stripes; i++) {
5393 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5394 /* write to new disk, too */
5395 struct btrfs_bio_stripe *new =
5396 bbio->stripes + index_where_to_add;
5397 struct btrfs_bio_stripe *old =
5398 bbio->stripes + i;
5399
5400 new->physical = old->physical;
5401 new->length = old->length;
5402 new->dev = dev_replace->tgtdev;
5403 bbio->tgtdev_map[i] = index_where_to_add;
5404 index_where_to_add++;
5405 max_errors++;
5406 tgtdev_indexes++;
5407 }
5408 }
5409 num_stripes = index_where_to_add;
5410 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
5411 dev_replace->tgtdev != NULL) {
5412 u64 srcdev_devid = dev_replace->srcdev->devid;
5413 int index_srcdev = 0;
5414 int found = 0;
5415 u64 physical_of_found = 0;
5416
5417 /*
5418 * During the dev-replace procedure, the target drive can
5419 * also be used to read data in case it is needed to repair
5420 * a corrupt block elsewhere. This is possible if the
5421 * requested area is left of the left cursor. In this area,
5422 * the target drive is a full copy of the source drive.
5423 */
5424 for (i = 0; i < num_stripes; i++) {
5425 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5426 /*
5427 * In case of DUP, in order to keep it
5428 * simple, only add the mirror with the
5429 * lowest physical address
5430 */
5431 if (found &&
5432 physical_of_found <=
5433 bbio->stripes[i].physical)
5434 continue;
5435 index_srcdev = i;
5436 found = 1;
5437 physical_of_found = bbio->stripes[i].physical;
5438 }
5439 }
5440 if (found) {
5441 if (physical_of_found + map->stripe_len <=
5442 dev_replace->cursor_left) {
5443 struct btrfs_bio_stripe *tgtdev_stripe =
5444 bbio->stripes + num_stripes;
5445
5446 tgtdev_stripe->physical = physical_of_found;
5447 tgtdev_stripe->length =
5448 bbio->stripes[index_srcdev].length;
5449 tgtdev_stripe->dev = dev_replace->tgtdev;
5450 bbio->tgtdev_map[index_srcdev] = num_stripes;
5451
5452 tgtdev_indexes++;
5453 num_stripes++;
5454 }
5455 }
5456 }
5457
5458 *bbio_ret = bbio;
5459 bbio->map_type = map->type;
5460 bbio->num_stripes = num_stripes;
5461 bbio->max_errors = max_errors;
5462 bbio->mirror_num = mirror_num;
5463 bbio->num_tgtdevs = tgtdev_indexes;
5464
5465 /*
5466 * this is the case that REQ_READ && dev_replace_is_ongoing &&
5467 * mirror_num == num_stripes + 1 && dev_replace target drive is
5468 * available as a mirror
5469 */
5470 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
5471 WARN_ON(num_stripes > 1);
5472 bbio->stripes[0].dev = dev_replace->tgtdev;
5473 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
5474 bbio->mirror_num = map->num_stripes + 1;
5475 }
5476 out:
5477 if (dev_replace_is_ongoing)
5478 btrfs_dev_replace_unlock(dev_replace);
5479 free_extent_map(em);
5480 return ret;
5481 }
5482
5483 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5484 u64 logical, u64 *length,
5485 struct btrfs_bio **bbio_ret, int mirror_num)
5486 {
5487 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5488 mirror_num, 0);
5489 }
5490
5491 /* For Scrub/replace */
5492 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
5493 u64 logical, u64 *length,
5494 struct btrfs_bio **bbio_ret, int mirror_num,
5495 int need_raid_map)
5496 {
5497 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5498 mirror_num, need_raid_map);
5499 }
5500
5501 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
5502 u64 chunk_start, u64 physical, u64 devid,
5503 u64 **logical, int *naddrs, int *stripe_len)
5504 {
5505 struct extent_map_tree *em_tree = &map_tree->map_tree;
5506 struct extent_map *em;
5507 struct map_lookup *map;
5508 u64 *buf;
5509 u64 bytenr;
5510 u64 length;
5511 u64 stripe_nr;
5512 u64 rmap_len;
5513 int i, j, nr = 0;
5514
5515 read_lock(&em_tree->lock);
5516 em = lookup_extent_mapping(em_tree, chunk_start, 1);
5517 read_unlock(&em_tree->lock);
5518
5519 if (!em) {
5520 printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
5521 chunk_start);
5522 return -EIO;
5523 }
5524
5525 if (em->start != chunk_start) {
5526 printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
5527 em->start, chunk_start);
5528 free_extent_map(em);
5529 return -EIO;
5530 }
5531 map = (struct map_lookup *)em->bdev;
5532
5533 length = em->len;
5534 rmap_len = map->stripe_len;
5535
5536 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5537 length = div_u64(length, map->num_stripes / map->sub_stripes);
5538 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5539 length = div_u64(length, map->num_stripes);
5540 else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5541 length = div_u64(length, nr_data_stripes(map));
5542 rmap_len = map->stripe_len * nr_data_stripes(map);
5543 }
5544
5545 buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
5546 BUG_ON(!buf); /* -ENOMEM */
5547
5548 for (i = 0; i < map->num_stripes; i++) {
5549 if (devid && map->stripes[i].dev->devid != devid)
5550 continue;
5551 if (map->stripes[i].physical > physical ||
5552 map->stripes[i].physical + length <= physical)
5553 continue;
5554
5555 stripe_nr = physical - map->stripes[i].physical;
5556 stripe_nr = div_u64(stripe_nr, map->stripe_len);
5557
5558 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5559 stripe_nr = stripe_nr * map->num_stripes + i;
5560 stripe_nr = div_u64(stripe_nr, map->sub_stripes);
5561 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5562 stripe_nr = stripe_nr * map->num_stripes + i;
5563 } /* else if RAID[56], multiply by nr_data_stripes().
5564 * Alternatively, just use rmap_len below instead of
5565 * map->stripe_len */
5566
5567 bytenr = chunk_start + stripe_nr * rmap_len;
5568 WARN_ON(nr >= map->num_stripes);
5569 for (j = 0; j < nr; j++) {
5570 if (buf[j] == bytenr)
5571 break;
5572 }
5573 if (j == nr) {
5574 WARN_ON(nr >= map->num_stripes);
5575 buf[nr++] = bytenr;
5576 }
5577 }
5578
5579 *logical = buf;
5580 *naddrs = nr;
5581 *stripe_len = rmap_len;
5582
5583 free_extent_map(em);
5584 return 0;
5585 }
5586
5587 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio, int err)
5588 {
5589 if (likely(bbio->flags & BTRFS_BIO_ORIG_BIO_SUBMITTED))
5590 bio_endio_nodec(bio, err);
5591 else
5592 bio_endio(bio, err);
5593 btrfs_put_bbio(bbio);
5594 }
5595
5596 static void btrfs_end_bio(struct bio *bio, int err)
5597 {
5598 struct btrfs_bio *bbio = bio->bi_private;
5599 struct btrfs_device *dev = bbio->stripes[0].dev;
5600 int is_orig_bio = 0;
5601
5602 if (err) {
5603 atomic_inc(&bbio->error);
5604 if (err == -EIO || err == -EREMOTEIO) {
5605 unsigned int stripe_index =
5606 btrfs_io_bio(bio)->stripe_index;
5607
5608 BUG_ON(stripe_index >= bbio->num_stripes);
5609 dev = bbio->stripes[stripe_index].dev;
5610 if (dev->bdev) {
5611 if (bio->bi_rw & WRITE)
5612 btrfs_dev_stat_inc(dev,
5613 BTRFS_DEV_STAT_WRITE_ERRS);
5614 else
5615 btrfs_dev_stat_inc(dev,
5616 BTRFS_DEV_STAT_READ_ERRS);
5617 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
5618 btrfs_dev_stat_inc(dev,
5619 BTRFS_DEV_STAT_FLUSH_ERRS);
5620 btrfs_dev_stat_print_on_error(dev);
5621 }
5622 }
5623 }
5624
5625 if (bio == bbio->orig_bio)
5626 is_orig_bio = 1;
5627
5628 btrfs_bio_counter_dec(bbio->fs_info);
5629
5630 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5631 if (!is_orig_bio) {
5632 bio_put(bio);
5633 bio = bbio->orig_bio;
5634 }
5635
5636 bio->bi_private = bbio->private;
5637 bio->bi_end_io = bbio->end_io;
5638 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5639 /* only send an error to the higher layers if it is
5640 * beyond the tolerance of the btrfs bio
5641 */
5642 if (atomic_read(&bbio->error) > bbio->max_errors) {
5643 err = -EIO;
5644 } else {
5645 /*
5646 * this bio is actually up to date, we didn't
5647 * go over the max number of errors
5648 */
5649 set_bit(BIO_UPTODATE, &bio->bi_flags);
5650 err = 0;
5651 }
5652
5653 btrfs_end_bbio(bbio, bio, err);
5654 } else if (!is_orig_bio) {
5655 bio_put(bio);
5656 }
5657 }
5658
5659 /*
5660 * see run_scheduled_bios for a description of why bios are collected for
5661 * async submit.
5662 *
5663 * This will add one bio to the pending list for a device and make sure
5664 * the work struct is scheduled.
5665 */
5666 static noinline void btrfs_schedule_bio(struct btrfs_root *root,
5667 struct btrfs_device *device,
5668 int rw, struct bio *bio)
5669 {
5670 int should_queue = 1;
5671 struct btrfs_pending_bios *pending_bios;
5672
5673 if (device->missing || !device->bdev) {
5674 bio_endio(bio, -EIO);
5675 return;
5676 }
5677
5678 /* don't bother with additional async steps for reads, right now */
5679 if (!(rw & REQ_WRITE)) {
5680 bio_get(bio);
5681 btrfsic_submit_bio(rw, bio);
5682 bio_put(bio);
5683 return;
5684 }
5685
5686 /*
5687 * nr_async_bios allows us to reliably return congestion to the
5688 * higher layers. Otherwise, the async bio makes it appear we have
5689 * made progress against dirty pages when we've really just put it
5690 * on a queue for later
5691 */
5692 atomic_inc(&root->fs_info->nr_async_bios);
5693 WARN_ON(bio->bi_next);
5694 bio->bi_next = NULL;
5695 bio->bi_rw |= rw;
5696
5697 spin_lock(&device->io_lock);
5698 if (bio->bi_rw & REQ_SYNC)
5699 pending_bios = &device->pending_sync_bios;
5700 else
5701 pending_bios = &device->pending_bios;
5702
5703 if (pending_bios->tail)
5704 pending_bios->tail->bi_next = bio;
5705
5706 pending_bios->tail = bio;
5707 if (!pending_bios->head)
5708 pending_bios->head = bio;
5709 if (device->running_pending)
5710 should_queue = 0;
5711
5712 spin_unlock(&device->io_lock);
5713
5714 if (should_queue)
5715 btrfs_queue_work(root->fs_info->submit_workers,
5716 &device->work);
5717 }
5718
5719 static int bio_size_ok(struct block_device *bdev, struct bio *bio,
5720 sector_t sector)
5721 {
5722 struct bio_vec *prev;
5723 struct request_queue *q = bdev_get_queue(bdev);
5724 unsigned int max_sectors = queue_max_sectors(q);
5725 struct bvec_merge_data bvm = {
5726 .bi_bdev = bdev,
5727 .bi_sector = sector,
5728 .bi_rw = bio->bi_rw,
5729 };
5730
5731 if (WARN_ON(bio->bi_vcnt == 0))
5732 return 1;
5733
5734 prev = &bio->bi_io_vec[bio->bi_vcnt - 1];
5735 if (bio_sectors(bio) > max_sectors)
5736 return 0;
5737
5738 if (!q->merge_bvec_fn)
5739 return 1;
5740
5741 bvm.bi_size = bio->bi_iter.bi_size - prev->bv_len;
5742 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len)
5743 return 0;
5744 return 1;
5745 }
5746
5747 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5748 struct bio *bio, u64 physical, int dev_nr,
5749 int rw, int async)
5750 {
5751 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
5752
5753 bio->bi_private = bbio;
5754 btrfs_io_bio(bio)->stripe_index = dev_nr;
5755 bio->bi_end_io = btrfs_end_bio;
5756 bio->bi_iter.bi_sector = physical >> 9;
5757 #ifdef DEBUG
5758 {
5759 struct rcu_string *name;
5760
5761 rcu_read_lock();
5762 name = rcu_dereference(dev->name);
5763 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
5764 "(%s id %llu), size=%u\n", rw,
5765 (u64)bio->bi_iter.bi_sector, (u_long)dev->bdev->bd_dev,
5766 name->str, dev->devid, bio->bi_iter.bi_size);
5767 rcu_read_unlock();
5768 }
5769 #endif
5770 bio->bi_bdev = dev->bdev;
5771
5772 btrfs_bio_counter_inc_noblocked(root->fs_info);
5773
5774 if (async)
5775 btrfs_schedule_bio(root, dev, rw, bio);
5776 else
5777 btrfsic_submit_bio(rw, bio);
5778 }
5779
5780 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5781 struct bio *first_bio, struct btrfs_device *dev,
5782 int dev_nr, int rw, int async)
5783 {
5784 struct bio_vec *bvec = first_bio->bi_io_vec;
5785 struct bio *bio;
5786 int nr_vecs = bio_get_nr_vecs(dev->bdev);
5787 u64 physical = bbio->stripes[dev_nr].physical;
5788
5789 again:
5790 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS);
5791 if (!bio)
5792 return -ENOMEM;
5793
5794 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) {
5795 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5796 bvec->bv_offset) < bvec->bv_len) {
5797 u64 len = bio->bi_iter.bi_size;
5798
5799 atomic_inc(&bbio->stripes_pending);
5800 submit_stripe_bio(root, bbio, bio, physical, dev_nr,
5801 rw, async);
5802 physical += len;
5803 goto again;
5804 }
5805 bvec++;
5806 }
5807
5808 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async);
5809 return 0;
5810 }
5811
5812 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
5813 {
5814 atomic_inc(&bbio->error);
5815 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5816 /* Shoud be the original bio. */
5817 WARN_ON(bio != bbio->orig_bio);
5818
5819 bio->bi_private = bbio->private;
5820 bio->bi_end_io = bbio->end_io;
5821 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5822 bio->bi_iter.bi_sector = logical >> 9;
5823
5824 btrfs_end_bbio(bbio, bio, -EIO);
5825 }
5826 }
5827
5828 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
5829 int mirror_num, int async_submit)
5830 {
5831 struct btrfs_device *dev;
5832 struct bio *first_bio = bio;
5833 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
5834 u64 length = 0;
5835 u64 map_length;
5836 int ret;
5837 int dev_nr;
5838 int total_devs;
5839 struct btrfs_bio *bbio = NULL;
5840
5841 length = bio->bi_iter.bi_size;
5842 map_length = length;
5843
5844 btrfs_bio_counter_inc_blocked(root->fs_info);
5845 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
5846 mirror_num, 1);
5847 if (ret) {
5848 btrfs_bio_counter_dec(root->fs_info);
5849 return ret;
5850 }
5851
5852 total_devs = bbio->num_stripes;
5853 bbio->orig_bio = first_bio;
5854 bbio->private = first_bio->bi_private;
5855 bbio->end_io = first_bio->bi_end_io;
5856 bbio->fs_info = root->fs_info;
5857 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
5858
5859 if (bbio->raid_map) {
5860 /* In this case, map_length has been set to the length of
5861 a single stripe; not the whole write */
5862 if (rw & WRITE) {
5863 ret = raid56_parity_write(root, bio, bbio, map_length);
5864 } else {
5865 ret = raid56_parity_recover(root, bio, bbio, map_length,
5866 mirror_num, 1);
5867 }
5868
5869 btrfs_bio_counter_dec(root->fs_info);
5870 return ret;
5871 }
5872
5873 if (map_length < length) {
5874 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
5875 logical, length, map_length);
5876 BUG();
5877 }
5878
5879 for (dev_nr = 0; dev_nr < total_devs; dev_nr++) {
5880 dev = bbio->stripes[dev_nr].dev;
5881 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
5882 bbio_error(bbio, first_bio, logical);
5883 continue;
5884 }
5885
5886 /*
5887 * Check and see if we're ok with this bio based on it's size
5888 * and offset with the given device.
5889 */
5890 if (!bio_size_ok(dev->bdev, first_bio,
5891 bbio->stripes[dev_nr].physical >> 9)) {
5892 ret = breakup_stripe_bio(root, bbio, first_bio, dev,
5893 dev_nr, rw, async_submit);
5894 BUG_ON(ret);
5895 continue;
5896 }
5897
5898 if (dev_nr < total_devs - 1) {
5899 bio = btrfs_bio_clone(first_bio, GFP_NOFS);
5900 BUG_ON(!bio); /* -ENOMEM */
5901 } else {
5902 bio = first_bio;
5903 bbio->flags |= BTRFS_BIO_ORIG_BIO_SUBMITTED;
5904 }
5905
5906 submit_stripe_bio(root, bbio, bio,
5907 bbio->stripes[dev_nr].physical, dev_nr, rw,
5908 async_submit);
5909 }
5910 btrfs_bio_counter_dec(root->fs_info);
5911 return 0;
5912 }
5913
5914 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
5915 u8 *uuid, u8 *fsid)
5916 {
5917 struct btrfs_device *device;
5918 struct btrfs_fs_devices *cur_devices;
5919
5920 cur_devices = fs_info->fs_devices;
5921 while (cur_devices) {
5922 if (!fsid ||
5923 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
5924 device = __find_device(&cur_devices->devices,
5925 devid, uuid);
5926 if (device)
5927 return device;
5928 }
5929 cur_devices = cur_devices->seed;
5930 }
5931 return NULL;
5932 }
5933
5934 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
5935 struct btrfs_fs_devices *fs_devices,
5936 u64 devid, u8 *dev_uuid)
5937 {
5938 struct btrfs_device *device;
5939
5940 device = btrfs_alloc_device(NULL, &devid, dev_uuid);
5941 if (IS_ERR(device))
5942 return NULL;
5943
5944 list_add(&device->dev_list, &fs_devices->devices);
5945 device->fs_devices = fs_devices;
5946 fs_devices->num_devices++;
5947
5948 device->missing = 1;
5949 fs_devices->missing_devices++;
5950
5951 return device;
5952 }
5953
5954 /**
5955 * btrfs_alloc_device - allocate struct btrfs_device
5956 * @fs_info: used only for generating a new devid, can be NULL if
5957 * devid is provided (i.e. @devid != NULL).
5958 * @devid: a pointer to devid for this device. If NULL a new devid
5959 * is generated.
5960 * @uuid: a pointer to UUID for this device. If NULL a new UUID
5961 * is generated.
5962 *
5963 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
5964 * on error. Returned struct is not linked onto any lists and can be
5965 * destroyed with kfree() right away.
5966 */
5967 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
5968 const u64 *devid,
5969 const u8 *uuid)
5970 {
5971 struct btrfs_device *dev;
5972 u64 tmp;
5973
5974 if (WARN_ON(!devid && !fs_info))
5975 return ERR_PTR(-EINVAL);
5976
5977 dev = __alloc_device();
5978 if (IS_ERR(dev))
5979 return dev;
5980
5981 if (devid)
5982 tmp = *devid;
5983 else {
5984 int ret;
5985
5986 ret = find_next_devid(fs_info, &tmp);
5987 if (ret) {
5988 kfree(dev);
5989 return ERR_PTR(ret);
5990 }
5991 }
5992 dev->devid = tmp;
5993
5994 if (uuid)
5995 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
5996 else
5997 generate_random_uuid(dev->uuid);
5998
5999 btrfs_init_work(&dev->work, btrfs_submit_helper,
6000 pending_bios_fn, NULL, NULL);
6001
6002 return dev;
6003 }
6004
6005 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
6006 struct extent_buffer *leaf,
6007 struct btrfs_chunk *chunk)
6008 {
6009 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
6010 struct map_lookup *map;
6011 struct extent_map *em;
6012 u64 logical;
6013 u64 length;
6014 u64 devid;
6015 u8 uuid[BTRFS_UUID_SIZE];
6016 int num_stripes;
6017 int ret;
6018 int i;
6019
6020 logical = key->offset;
6021 length = btrfs_chunk_length(leaf, chunk);
6022
6023 read_lock(&map_tree->map_tree.lock);
6024 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
6025 read_unlock(&map_tree->map_tree.lock);
6026
6027 /* already mapped? */
6028 if (em && em->start <= logical && em->start + em->len > logical) {
6029 free_extent_map(em);
6030 return 0;
6031 } else if (em) {
6032 free_extent_map(em);
6033 }
6034
6035 em = alloc_extent_map();
6036 if (!em)
6037 return -ENOMEM;
6038 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
6039 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
6040 if (!map) {
6041 free_extent_map(em);
6042 return -ENOMEM;
6043 }
6044
6045 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
6046 em->bdev = (struct block_device *)map;
6047 em->start = logical;
6048 em->len = length;
6049 em->orig_start = 0;
6050 em->block_start = 0;
6051 em->block_len = em->len;
6052
6053 map->num_stripes = num_stripes;
6054 map->io_width = btrfs_chunk_io_width(leaf, chunk);
6055 map->io_align = btrfs_chunk_io_align(leaf, chunk);
6056 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
6057 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6058 map->type = btrfs_chunk_type(leaf, chunk);
6059 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
6060 for (i = 0; i < num_stripes; i++) {
6061 map->stripes[i].physical =
6062 btrfs_stripe_offset_nr(leaf, chunk, i);
6063 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
6064 read_extent_buffer(leaf, uuid, (unsigned long)
6065 btrfs_stripe_dev_uuid_nr(chunk, i),
6066 BTRFS_UUID_SIZE);
6067 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
6068 uuid, NULL);
6069 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
6070 free_extent_map(em);
6071 return -EIO;
6072 }
6073 if (!map->stripes[i].dev) {
6074 map->stripes[i].dev =
6075 add_missing_dev(root, root->fs_info->fs_devices,
6076 devid, uuid);
6077 if (!map->stripes[i].dev) {
6078 free_extent_map(em);
6079 return -EIO;
6080 }
6081 }
6082 map->stripes[i].dev->in_fs_metadata = 1;
6083 }
6084
6085 write_lock(&map_tree->map_tree.lock);
6086 ret = add_extent_mapping(&map_tree->map_tree, em, 0);
6087 write_unlock(&map_tree->map_tree.lock);
6088 BUG_ON(ret); /* Tree corruption */
6089 free_extent_map(em);
6090
6091 return 0;
6092 }
6093
6094 static void fill_device_from_item(struct extent_buffer *leaf,
6095 struct btrfs_dev_item *dev_item,
6096 struct btrfs_device *device)
6097 {
6098 unsigned long ptr;
6099
6100 device->devid = btrfs_device_id(leaf, dev_item);
6101 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
6102 device->total_bytes = device->disk_total_bytes;
6103 device->commit_total_bytes = device->disk_total_bytes;
6104 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
6105 device->commit_bytes_used = device->bytes_used;
6106 device->type = btrfs_device_type(leaf, dev_item);
6107 device->io_align = btrfs_device_io_align(leaf, dev_item);
6108 device->io_width = btrfs_device_io_width(leaf, dev_item);
6109 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
6110 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
6111 device->is_tgtdev_for_dev_replace = 0;
6112
6113 ptr = btrfs_device_uuid(dev_item);
6114 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
6115 }
6116
6117 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_root *root,
6118 u8 *fsid)
6119 {
6120 struct btrfs_fs_devices *fs_devices;
6121 int ret;
6122
6123 BUG_ON(!mutex_is_locked(&uuid_mutex));
6124
6125 fs_devices = root->fs_info->fs_devices->seed;
6126 while (fs_devices) {
6127 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE))
6128 return fs_devices;
6129
6130 fs_devices = fs_devices->seed;
6131 }
6132
6133 fs_devices = find_fsid(fsid);
6134 if (!fs_devices) {
6135 if (!btrfs_test_opt(root, DEGRADED))
6136 return ERR_PTR(-ENOENT);
6137
6138 fs_devices = alloc_fs_devices(fsid);
6139 if (IS_ERR(fs_devices))
6140 return fs_devices;
6141
6142 fs_devices->seeding = 1;
6143 fs_devices->opened = 1;
6144 return fs_devices;
6145 }
6146
6147 fs_devices = clone_fs_devices(fs_devices);
6148 if (IS_ERR(fs_devices))
6149 return fs_devices;
6150
6151 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
6152 root->fs_info->bdev_holder);
6153 if (ret) {
6154 free_fs_devices(fs_devices);
6155 fs_devices = ERR_PTR(ret);
6156 goto out;
6157 }
6158
6159 if (!fs_devices->seeding) {
6160 __btrfs_close_devices(fs_devices);
6161 free_fs_devices(fs_devices);
6162 fs_devices = ERR_PTR(-EINVAL);
6163 goto out;
6164 }
6165
6166 fs_devices->seed = root->fs_info->fs_devices->seed;
6167 root->fs_info->fs_devices->seed = fs_devices;
6168 out:
6169 return fs_devices;
6170 }
6171
6172 static int read_one_dev(struct btrfs_root *root,
6173 struct extent_buffer *leaf,
6174 struct btrfs_dev_item *dev_item)
6175 {
6176 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6177 struct btrfs_device *device;
6178 u64 devid;
6179 int ret;
6180 u8 fs_uuid[BTRFS_UUID_SIZE];
6181 u8 dev_uuid[BTRFS_UUID_SIZE];
6182
6183 devid = btrfs_device_id(leaf, dev_item);
6184 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
6185 BTRFS_UUID_SIZE);
6186 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
6187 BTRFS_UUID_SIZE);
6188
6189 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
6190 fs_devices = open_seed_devices(root, fs_uuid);
6191 if (IS_ERR(fs_devices))
6192 return PTR_ERR(fs_devices);
6193 }
6194
6195 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
6196 if (!device) {
6197 if (!btrfs_test_opt(root, DEGRADED))
6198 return -EIO;
6199
6200 btrfs_warn(root->fs_info, "devid %llu missing", devid);
6201 device = add_missing_dev(root, fs_devices, devid, dev_uuid);
6202 if (!device)
6203 return -ENOMEM;
6204 } else {
6205 if (!device->bdev && !btrfs_test_opt(root, DEGRADED))
6206 return -EIO;
6207
6208 if(!device->bdev && !device->missing) {
6209 /*
6210 * this happens when a device that was properly setup
6211 * in the device info lists suddenly goes bad.
6212 * device->bdev is NULL, and so we have to set
6213 * device->missing to one here
6214 */
6215 device->fs_devices->missing_devices++;
6216 device->missing = 1;
6217 }
6218
6219 /* Move the device to its own fs_devices */
6220 if (device->fs_devices != fs_devices) {
6221 ASSERT(device->missing);
6222
6223 list_move(&device->dev_list, &fs_devices->devices);
6224 device->fs_devices->num_devices--;
6225 fs_devices->num_devices++;
6226
6227 device->fs_devices->missing_devices--;
6228 fs_devices->missing_devices++;
6229
6230 device->fs_devices = fs_devices;
6231 }
6232 }
6233
6234 if (device->fs_devices != root->fs_info->fs_devices) {
6235 BUG_ON(device->writeable);
6236 if (device->generation !=
6237 btrfs_device_generation(leaf, dev_item))
6238 return -EINVAL;
6239 }
6240
6241 fill_device_from_item(leaf, dev_item, device);
6242 device->in_fs_metadata = 1;
6243 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
6244 device->fs_devices->total_rw_bytes += device->total_bytes;
6245 spin_lock(&root->fs_info->free_chunk_lock);
6246 root->fs_info->free_chunk_space += device->total_bytes -
6247 device->bytes_used;
6248 spin_unlock(&root->fs_info->free_chunk_lock);
6249 }
6250 ret = 0;
6251 return ret;
6252 }
6253
6254 int btrfs_read_sys_array(struct btrfs_root *root)
6255 {
6256 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
6257 struct extent_buffer *sb;
6258 struct btrfs_disk_key *disk_key;
6259 struct btrfs_chunk *chunk;
6260 u8 *array_ptr;
6261 unsigned long sb_array_offset;
6262 int ret = 0;
6263 u32 num_stripes;
6264 u32 array_size;
6265 u32 len = 0;
6266 u32 cur_offset;
6267 struct btrfs_key key;
6268
6269 ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
6270 /*
6271 * This will create extent buffer of nodesize, superblock size is
6272 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
6273 * overallocate but we can keep it as-is, only the first page is used.
6274 */
6275 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
6276 if (!sb)
6277 return -ENOMEM;
6278 btrfs_set_buffer_uptodate(sb);
6279 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
6280 /*
6281 * The sb extent buffer is artifical and just used to read the system array.
6282 * btrfs_set_buffer_uptodate() call does not properly mark all it's
6283 * pages up-to-date when the page is larger: extent does not cover the
6284 * whole page and consequently check_page_uptodate does not find all
6285 * the page's extents up-to-date (the hole beyond sb),
6286 * write_extent_buffer then triggers a WARN_ON.
6287 *
6288 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
6289 * but sb spans only this function. Add an explicit SetPageUptodate call
6290 * to silence the warning eg. on PowerPC 64.
6291 */
6292 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
6293 SetPageUptodate(sb->pages[0]);
6294
6295 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
6296 array_size = btrfs_super_sys_array_size(super_copy);
6297
6298 array_ptr = super_copy->sys_chunk_array;
6299 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
6300 cur_offset = 0;
6301
6302 while (cur_offset < array_size) {
6303 disk_key = (struct btrfs_disk_key *)array_ptr;
6304 len = sizeof(*disk_key);
6305 if (cur_offset + len > array_size)
6306 goto out_short_read;
6307
6308 btrfs_disk_key_to_cpu(&key, disk_key);
6309
6310 array_ptr += len;
6311 sb_array_offset += len;
6312 cur_offset += len;
6313
6314 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6315 chunk = (struct btrfs_chunk *)sb_array_offset;
6316 /*
6317 * At least one btrfs_chunk with one stripe must be
6318 * present, exact stripe count check comes afterwards
6319 */
6320 len = btrfs_chunk_item_size(1);
6321 if (cur_offset + len > array_size)
6322 goto out_short_read;
6323
6324 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
6325 len = btrfs_chunk_item_size(num_stripes);
6326 if (cur_offset + len > array_size)
6327 goto out_short_read;
6328
6329 ret = read_one_chunk(root, &key, sb, chunk);
6330 if (ret)
6331 break;
6332 } else {
6333 ret = -EIO;
6334 break;
6335 }
6336 array_ptr += len;
6337 sb_array_offset += len;
6338 cur_offset += len;
6339 }
6340 free_extent_buffer(sb);
6341 return ret;
6342
6343 out_short_read:
6344 printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
6345 len, cur_offset);
6346 free_extent_buffer(sb);
6347 return -EIO;
6348 }
6349
6350 int btrfs_read_chunk_tree(struct btrfs_root *root)
6351 {
6352 struct btrfs_path *path;
6353 struct extent_buffer *leaf;
6354 struct btrfs_key key;
6355 struct btrfs_key found_key;
6356 int ret;
6357 int slot;
6358
6359 root = root->fs_info->chunk_root;
6360
6361 path = btrfs_alloc_path();
6362 if (!path)
6363 return -ENOMEM;
6364
6365 mutex_lock(&uuid_mutex);
6366 lock_chunks(root);
6367
6368 /*
6369 * Read all device items, and then all the chunk items. All
6370 * device items are found before any chunk item (their object id
6371 * is smaller than the lowest possible object id for a chunk
6372 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
6373 */
6374 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
6375 key.offset = 0;
6376 key.type = 0;
6377 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6378 if (ret < 0)
6379 goto error;
6380 while (1) {
6381 leaf = path->nodes[0];
6382 slot = path->slots[0];
6383 if (slot >= btrfs_header_nritems(leaf)) {
6384 ret = btrfs_next_leaf(root, path);
6385 if (ret == 0)
6386 continue;
6387 if (ret < 0)
6388 goto error;
6389 break;
6390 }
6391 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6392 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
6393 struct btrfs_dev_item *dev_item;
6394 dev_item = btrfs_item_ptr(leaf, slot,
6395 struct btrfs_dev_item);
6396 ret = read_one_dev(root, leaf, dev_item);
6397 if (ret)
6398 goto error;
6399 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
6400 struct btrfs_chunk *chunk;
6401 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
6402 ret = read_one_chunk(root, &found_key, leaf, chunk);
6403 if (ret)
6404 goto error;
6405 }
6406 path->slots[0]++;
6407 }
6408 ret = 0;
6409 error:
6410 unlock_chunks(root);
6411 mutex_unlock(&uuid_mutex);
6412
6413 btrfs_free_path(path);
6414 return ret;
6415 }
6416
6417 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
6418 {
6419 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6420 struct btrfs_device *device;
6421
6422 while (fs_devices) {
6423 mutex_lock(&fs_devices->device_list_mutex);
6424 list_for_each_entry(device, &fs_devices->devices, dev_list)
6425 device->dev_root = fs_info->dev_root;
6426 mutex_unlock(&fs_devices->device_list_mutex);
6427
6428 fs_devices = fs_devices->seed;
6429 }
6430 }
6431
6432 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
6433 {
6434 int i;
6435
6436 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6437 btrfs_dev_stat_reset(dev, i);
6438 }
6439
6440 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
6441 {
6442 struct btrfs_key key;
6443 struct btrfs_key found_key;
6444 struct btrfs_root *dev_root = fs_info->dev_root;
6445 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6446 struct extent_buffer *eb;
6447 int slot;
6448 int ret = 0;
6449 struct btrfs_device *device;
6450 struct btrfs_path *path = NULL;
6451 int i;
6452
6453 path = btrfs_alloc_path();
6454 if (!path) {
6455 ret = -ENOMEM;
6456 goto out;
6457 }
6458
6459 mutex_lock(&fs_devices->device_list_mutex);
6460 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6461 int item_size;
6462 struct btrfs_dev_stats_item *ptr;
6463
6464 key.objectid = 0;
6465 key.type = BTRFS_DEV_STATS_KEY;
6466 key.offset = device->devid;
6467 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
6468 if (ret) {
6469 __btrfs_reset_dev_stats(device);
6470 device->dev_stats_valid = 1;
6471 btrfs_release_path(path);
6472 continue;
6473 }
6474 slot = path->slots[0];
6475 eb = path->nodes[0];
6476 btrfs_item_key_to_cpu(eb, &found_key, slot);
6477 item_size = btrfs_item_size_nr(eb, slot);
6478
6479 ptr = btrfs_item_ptr(eb, slot,
6480 struct btrfs_dev_stats_item);
6481
6482 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6483 if (item_size >= (1 + i) * sizeof(__le64))
6484 btrfs_dev_stat_set(device, i,
6485 btrfs_dev_stats_value(eb, ptr, i));
6486 else
6487 btrfs_dev_stat_reset(device, i);
6488 }
6489
6490 device->dev_stats_valid = 1;
6491 btrfs_dev_stat_print_on_load(device);
6492 btrfs_release_path(path);
6493 }
6494 mutex_unlock(&fs_devices->device_list_mutex);
6495
6496 out:
6497 btrfs_free_path(path);
6498 return ret < 0 ? ret : 0;
6499 }
6500
6501 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
6502 struct btrfs_root *dev_root,
6503 struct btrfs_device *device)
6504 {
6505 struct btrfs_path *path;
6506 struct btrfs_key key;
6507 struct extent_buffer *eb;
6508 struct btrfs_dev_stats_item *ptr;
6509 int ret;
6510 int i;
6511
6512 key.objectid = 0;
6513 key.type = BTRFS_DEV_STATS_KEY;
6514 key.offset = device->devid;
6515
6516 path = btrfs_alloc_path();
6517 BUG_ON(!path);
6518 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
6519 if (ret < 0) {
6520 printk_in_rcu(KERN_WARNING "BTRFS: "
6521 "error %d while searching for dev_stats item for device %s!\n",
6522 ret, rcu_str_deref(device->name));
6523 goto out;
6524 }
6525
6526 if (ret == 0 &&
6527 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
6528 /* need to delete old one and insert a new one */
6529 ret = btrfs_del_item(trans, dev_root, path);
6530 if (ret != 0) {
6531 printk_in_rcu(KERN_WARNING "BTRFS: "
6532 "delete too small dev_stats item for device %s failed %d!\n",
6533 rcu_str_deref(device->name), ret);
6534 goto out;
6535 }
6536 ret = 1;
6537 }
6538
6539 if (ret == 1) {
6540 /* need to insert a new item */
6541 btrfs_release_path(path);
6542 ret = btrfs_insert_empty_item(trans, dev_root, path,
6543 &key, sizeof(*ptr));
6544 if (ret < 0) {
6545 printk_in_rcu(KERN_WARNING "BTRFS: "
6546 "insert dev_stats item for device %s failed %d!\n",
6547 rcu_str_deref(device->name), ret);
6548 goto out;
6549 }
6550 }
6551
6552 eb = path->nodes[0];
6553 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
6554 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6555 btrfs_set_dev_stats_value(eb, ptr, i,
6556 btrfs_dev_stat_read(device, i));
6557 btrfs_mark_buffer_dirty(eb);
6558
6559 out:
6560 btrfs_free_path(path);
6561 return ret;
6562 }
6563
6564 /*
6565 * called from commit_transaction. Writes all changed device stats to disk.
6566 */
6567 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
6568 struct btrfs_fs_info *fs_info)
6569 {
6570 struct btrfs_root *dev_root = fs_info->dev_root;
6571 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6572 struct btrfs_device *device;
6573 int stats_cnt;
6574 int ret = 0;
6575
6576 mutex_lock(&fs_devices->device_list_mutex);
6577 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6578 if (!device->dev_stats_valid || !btrfs_dev_stats_dirty(device))
6579 continue;
6580
6581 stats_cnt = atomic_read(&device->dev_stats_ccnt);
6582 ret = update_dev_stat_item(trans, dev_root, device);
6583 if (!ret)
6584 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
6585 }
6586 mutex_unlock(&fs_devices->device_list_mutex);
6587
6588 return ret;
6589 }
6590
6591 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
6592 {
6593 btrfs_dev_stat_inc(dev, index);
6594 btrfs_dev_stat_print_on_error(dev);
6595 }
6596
6597 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
6598 {
6599 if (!dev->dev_stats_valid)
6600 return;
6601 printk_ratelimited_in_rcu(KERN_ERR "BTRFS: "
6602 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6603 rcu_str_deref(dev->name),
6604 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6605 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6606 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6607 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6608 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6609 }
6610
6611 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
6612 {
6613 int i;
6614
6615 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6616 if (btrfs_dev_stat_read(dev, i) != 0)
6617 break;
6618 if (i == BTRFS_DEV_STAT_VALUES_MAX)
6619 return; /* all values == 0, suppress message */
6620
6621 printk_in_rcu(KERN_INFO "BTRFS: "
6622 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6623 rcu_str_deref(dev->name),
6624 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6625 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6626 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6627 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6628 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6629 }
6630
6631 int btrfs_get_dev_stats(struct btrfs_root *root,
6632 struct btrfs_ioctl_get_dev_stats *stats)
6633 {
6634 struct btrfs_device *dev;
6635 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6636 int i;
6637
6638 mutex_lock(&fs_devices->device_list_mutex);
6639 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
6640 mutex_unlock(&fs_devices->device_list_mutex);
6641
6642 if (!dev) {
6643 btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
6644 return -ENODEV;
6645 } else if (!dev->dev_stats_valid) {
6646 btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
6647 return -ENODEV;
6648 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
6649 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6650 if (stats->nr_items > i)
6651 stats->values[i] =
6652 btrfs_dev_stat_read_and_reset(dev, i);
6653 else
6654 btrfs_dev_stat_reset(dev, i);
6655 }
6656 } else {
6657 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6658 if (stats->nr_items > i)
6659 stats->values[i] = btrfs_dev_stat_read(dev, i);
6660 }
6661 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
6662 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
6663 return 0;
6664 }
6665
6666 int btrfs_scratch_superblock(struct btrfs_device *device)
6667 {
6668 struct buffer_head *bh;
6669 struct btrfs_super_block *disk_super;
6670
6671 bh = btrfs_read_dev_super(device->bdev);
6672 if (!bh)
6673 return -EINVAL;
6674 disk_super = (struct btrfs_super_block *)bh->b_data;
6675
6676 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
6677 set_buffer_dirty(bh);
6678 sync_dirty_buffer(bh);
6679 brelse(bh);
6680
6681 return 0;
6682 }
6683
6684 /*
6685 * Update the size of all devices, which is used for writing out the
6686 * super blocks.
6687 */
6688 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info)
6689 {
6690 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6691 struct btrfs_device *curr, *next;
6692
6693 if (list_empty(&fs_devices->resized_devices))
6694 return;
6695
6696 mutex_lock(&fs_devices->device_list_mutex);
6697 lock_chunks(fs_info->dev_root);
6698 list_for_each_entry_safe(curr, next, &fs_devices->resized_devices,
6699 resized_list) {
6700 list_del_init(&curr->resized_list);
6701 curr->commit_total_bytes = curr->disk_total_bytes;
6702 }
6703 unlock_chunks(fs_info->dev_root);
6704 mutex_unlock(&fs_devices->device_list_mutex);
6705 }
6706
6707 /* Must be invoked during the transaction commit */
6708 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
6709 struct btrfs_transaction *transaction)
6710 {
6711 struct extent_map *em;
6712 struct map_lookup *map;
6713 struct btrfs_device *dev;
6714 int i;
6715
6716 if (list_empty(&transaction->pending_chunks))
6717 return;
6718
6719 /* In order to kick the device replace finish process */
6720 lock_chunks(root);
6721 list_for_each_entry(em, &transaction->pending_chunks, list) {
6722 map = (struct map_lookup *)em->bdev;
6723
6724 for (i = 0; i < map->num_stripes; i++) {
6725 dev = map->stripes[i].dev;
6726 dev->commit_bytes_used = dev->bytes_used;
6727 }
6728 }
6729 unlock_chunks(root);
6730 }
Linux kernel - Deliverables
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