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Merge tag 'fbdev-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux
[deliverable/linux.git] / fs / btrfs / volumes.c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18 #include <linux/sched.h>
19 #include <linux/bio.h>
20 #include <linux/slab.h>
21 #include <linux/buffer_head.h>
22 #include <linux/blkdev.h>
23 #include <linux/random.h>
24 #include <linux/iocontext.h>
25 #include <linux/capability.h>
26 #include <linux/ratelimit.h>
27 #include <linux/kthread.h>
28 #include <linux/raid/pq.h>
29 #include <linux/semaphore.h>
30 #include <asm/div64.h>
31 #include "ctree.h"
32 #include "extent_map.h"
33 #include "disk-io.h"
34 #include "transaction.h"
35 #include "print-tree.h"
36 #include "volumes.h"
37 #include "raid56.h"
38 #include "async-thread.h"
39 #include "check-integrity.h"
40 #include "rcu-string.h"
41 #include "math.h"
42 #include "dev-replace.h"
43 #include "sysfs.h"
44
45 static int init_first_rw_device(struct btrfs_trans_handle *trans,
46 struct btrfs_root *root,
47 struct btrfs_device *device);
48 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
49 static void __btrfs_reset_dev_stats(struct btrfs_device *dev);
50 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev);
51 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
52
53 DEFINE_MUTEX(uuid_mutex);
54 static LIST_HEAD(fs_uuids);
55 struct list_head *btrfs_get_fs_uuids(void)
56 {
57 return &fs_uuids;
58 }
59
60 static struct btrfs_fs_devices *__alloc_fs_devices(void)
61 {
62 struct btrfs_fs_devices *fs_devs;
63
64 fs_devs = kzalloc(sizeof(*fs_devs), GFP_NOFS);
65 if (!fs_devs)
66 return ERR_PTR(-ENOMEM);
67
68 mutex_init(&fs_devs->device_list_mutex);
69
70 INIT_LIST_HEAD(&fs_devs->devices);
71 INIT_LIST_HEAD(&fs_devs->resized_devices);
72 INIT_LIST_HEAD(&fs_devs->alloc_list);
73 INIT_LIST_HEAD(&fs_devs->list);
74
75 return fs_devs;
76 }
77
78 /**
79 * alloc_fs_devices - allocate struct btrfs_fs_devices
80 * @fsid: a pointer to UUID for this FS. If NULL a new UUID is
81 * generated.
82 *
83 * Return: a pointer to a new &struct btrfs_fs_devices on success;
84 * ERR_PTR() on error. Returned struct is not linked onto any lists and
85 * can be destroyed with kfree() right away.
86 */
87 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
88 {
89 struct btrfs_fs_devices *fs_devs;
90
91 fs_devs = __alloc_fs_devices();
92 if (IS_ERR(fs_devs))
93 return fs_devs;
94
95 if (fsid)
96 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
97 else
98 generate_random_uuid(fs_devs->fsid);
99
100 return fs_devs;
101 }
102
103 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
104 {
105 struct btrfs_device *device;
106 WARN_ON(fs_devices->opened);
107 while (!list_empty(&fs_devices->devices)) {
108 device = list_entry(fs_devices->devices.next,
109 struct btrfs_device, dev_list);
110 list_del(&device->dev_list);
111 rcu_string_free(device->name);
112 kfree(device);
113 }
114 kfree(fs_devices);
115 }
116
117 static void btrfs_kobject_uevent(struct block_device *bdev,
118 enum kobject_action action)
119 {
120 int ret;
121
122 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
123 if (ret)
124 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
125 action,
126 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
127 &disk_to_dev(bdev->bd_disk)->kobj);
128 }
129
130 void btrfs_cleanup_fs_uuids(void)
131 {
132 struct btrfs_fs_devices *fs_devices;
133
134 while (!list_empty(&fs_uuids)) {
135 fs_devices = list_entry(fs_uuids.next,
136 struct btrfs_fs_devices, list);
137 list_del(&fs_devices->list);
138 free_fs_devices(fs_devices);
139 }
140 }
141
142 static struct btrfs_device *__alloc_device(void)
143 {
144 struct btrfs_device *dev;
145
146 dev = kzalloc(sizeof(*dev), GFP_NOFS);
147 if (!dev)
148 return ERR_PTR(-ENOMEM);
149
150 INIT_LIST_HEAD(&dev->dev_list);
151 INIT_LIST_HEAD(&dev->dev_alloc_list);
152 INIT_LIST_HEAD(&dev->resized_list);
153
154 spin_lock_init(&dev->io_lock);
155
156 spin_lock_init(&dev->reada_lock);
157 atomic_set(&dev->reada_in_flight, 0);
158 atomic_set(&dev->dev_stats_ccnt, 0);
159 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_WAIT);
160 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_WAIT);
161
162 return dev;
163 }
164
165 static noinline struct btrfs_device *__find_device(struct list_head *head,
166 u64 devid, u8 *uuid)
167 {
168 struct btrfs_device *dev;
169
170 list_for_each_entry(dev, head, dev_list) {
171 if (dev->devid == devid &&
172 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
173 return dev;
174 }
175 }
176 return NULL;
177 }
178
179 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
180 {
181 struct btrfs_fs_devices *fs_devices;
182
183 list_for_each_entry(fs_devices, &fs_uuids, list) {
184 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
185 return fs_devices;
186 }
187 return NULL;
188 }
189
190 static int
191 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
192 int flush, struct block_device **bdev,
193 struct buffer_head **bh)
194 {
195 int ret;
196
197 *bdev = blkdev_get_by_path(device_path, flags, holder);
198
199 if (IS_ERR(*bdev)) {
200 ret = PTR_ERR(*bdev);
201 printk(KERN_INFO "BTRFS: open %s failed\n", device_path);
202 goto error;
203 }
204
205 if (flush)
206 filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
207 ret = set_blocksize(*bdev, 4096);
208 if (ret) {
209 blkdev_put(*bdev, flags);
210 goto error;
211 }
212 invalidate_bdev(*bdev);
213 *bh = btrfs_read_dev_super(*bdev);
214 if (!*bh) {
215 ret = -EINVAL;
216 blkdev_put(*bdev, flags);
217 goto error;
218 }
219
220 return 0;
221
222 error:
223 *bdev = NULL;
224 *bh = NULL;
225 return ret;
226 }
227
228 static void requeue_list(struct btrfs_pending_bios *pending_bios,
229 struct bio *head, struct bio *tail)
230 {
231
232 struct bio *old_head;
233
234 old_head = pending_bios->head;
235 pending_bios->head = head;
236 if (pending_bios->tail)
237 tail->bi_next = old_head;
238 else
239 pending_bios->tail = tail;
240 }
241
242 /*
243 * we try to collect pending bios for a device so we don't get a large
244 * number of procs sending bios down to the same device. This greatly
245 * improves the schedulers ability to collect and merge the bios.
246 *
247 * But, it also turns into a long list of bios to process and that is sure
248 * to eventually make the worker thread block. The solution here is to
249 * make some progress and then put this work struct back at the end of
250 * the list if the block device is congested. This way, multiple devices
251 * can make progress from a single worker thread.
252 */
253 static noinline void run_scheduled_bios(struct btrfs_device *device)
254 {
255 struct bio *pending;
256 struct backing_dev_info *bdi;
257 struct btrfs_fs_info *fs_info;
258 struct btrfs_pending_bios *pending_bios;
259 struct bio *tail;
260 struct bio *cur;
261 int again = 0;
262 unsigned long num_run;
263 unsigned long batch_run = 0;
264 unsigned long limit;
265 unsigned long last_waited = 0;
266 int force_reg = 0;
267 int sync_pending = 0;
268 struct blk_plug plug;
269
270 /*
271 * this function runs all the bios we've collected for
272 * a particular device. We don't want to wander off to
273 * another device without first sending all of these down.
274 * So, setup a plug here and finish it off before we return
275 */
276 blk_start_plug(&plug);
277
278 bdi = blk_get_backing_dev_info(device->bdev);
279 fs_info = device->dev_root->fs_info;
280 limit = btrfs_async_submit_limit(fs_info);
281 limit = limit * 2 / 3;
282
283 loop:
284 spin_lock(&device->io_lock);
285
286 loop_lock:
287 num_run = 0;
288
289 /* take all the bios off the list at once and process them
290 * later on (without the lock held). But, remember the
291 * tail and other pointers so the bios can be properly reinserted
292 * into the list if we hit congestion
293 */
294 if (!force_reg && device->pending_sync_bios.head) {
295 pending_bios = &device->pending_sync_bios;
296 force_reg = 1;
297 } else {
298 pending_bios = &device->pending_bios;
299 force_reg = 0;
300 }
301
302 pending = pending_bios->head;
303 tail = pending_bios->tail;
304 WARN_ON(pending && !tail);
305
306 /*
307 * if pending was null this time around, no bios need processing
308 * at all and we can stop. Otherwise it'll loop back up again
309 * and do an additional check so no bios are missed.
310 *
311 * device->running_pending is used to synchronize with the
312 * schedule_bio code.
313 */
314 if (device->pending_sync_bios.head == NULL &&
315 device->pending_bios.head == NULL) {
316 again = 0;
317 device->running_pending = 0;
318 } else {
319 again = 1;
320 device->running_pending = 1;
321 }
322
323 pending_bios->head = NULL;
324 pending_bios->tail = NULL;
325
326 spin_unlock(&device->io_lock);
327
328 while (pending) {
329
330 rmb();
331 /* we want to work on both lists, but do more bios on the
332 * sync list than the regular list
333 */
334 if ((num_run > 32 &&
335 pending_bios != &device->pending_sync_bios &&
336 device->pending_sync_bios.head) ||
337 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
338 device->pending_bios.head)) {
339 spin_lock(&device->io_lock);
340 requeue_list(pending_bios, pending, tail);
341 goto loop_lock;
342 }
343
344 cur = pending;
345 pending = pending->bi_next;
346 cur->bi_next = NULL;
347
348 if (atomic_dec_return(&fs_info->nr_async_bios) < limit &&
349 waitqueue_active(&fs_info->async_submit_wait))
350 wake_up(&fs_info->async_submit_wait);
351
352 BUG_ON(atomic_read(&cur->__bi_cnt) == 0);
353
354 /*
355 * if we're doing the sync list, record that our
356 * plug has some sync requests on it
357 *
358 * If we're doing the regular list and there are
359 * sync requests sitting around, unplug before
360 * we add more
361 */
362 if (pending_bios == &device->pending_sync_bios) {
363 sync_pending = 1;
364 } else if (sync_pending) {
365 blk_finish_plug(&plug);
366 blk_start_plug(&plug);
367 sync_pending = 0;
368 }
369
370 btrfsic_submit_bio(cur->bi_rw, cur);
371 num_run++;
372 batch_run++;
373
374 cond_resched();
375
376 /*
377 * we made progress, there is more work to do and the bdi
378 * is now congested. Back off and let other work structs
379 * run instead
380 */
381 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
382 fs_info->fs_devices->open_devices > 1) {
383 struct io_context *ioc;
384
385 ioc = current->io_context;
386
387 /*
388 * the main goal here is that we don't want to
389 * block if we're going to be able to submit
390 * more requests without blocking.
391 *
392 * This code does two great things, it pokes into
393 * the elevator code from a filesystem _and_
394 * it makes assumptions about how batching works.
395 */
396 if (ioc && ioc->nr_batch_requests > 0 &&
397 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
398 (last_waited == 0 ||
399 ioc->last_waited == last_waited)) {
400 /*
401 * we want to go through our batch of
402 * requests and stop. So, we copy out
403 * the ioc->last_waited time and test
404 * against it before looping
405 */
406 last_waited = ioc->last_waited;
407 cond_resched();
408 continue;
409 }
410 spin_lock(&device->io_lock);
411 requeue_list(pending_bios, pending, tail);
412 device->running_pending = 1;
413
414 spin_unlock(&device->io_lock);
415 btrfs_queue_work(fs_info->submit_workers,
416 &device->work);
417 goto done;
418 }
419 /* unplug every 64 requests just for good measure */
420 if (batch_run % 64 == 0) {
421 blk_finish_plug(&plug);
422 blk_start_plug(&plug);
423 sync_pending = 0;
424 }
425 }
426
427 cond_resched();
428 if (again)
429 goto loop;
430
431 spin_lock(&device->io_lock);
432 if (device->pending_bios.head || device->pending_sync_bios.head)
433 goto loop_lock;
434 spin_unlock(&device->io_lock);
435
436 done:
437 blk_finish_plug(&plug);
438 }
439
440 static void pending_bios_fn(struct btrfs_work *work)
441 {
442 struct btrfs_device *device;
443
444 device = container_of(work, struct btrfs_device, work);
445 run_scheduled_bios(device);
446 }
447
448
449 void btrfs_free_stale_device(struct btrfs_device *cur_dev)
450 {
451 struct btrfs_fs_devices *fs_devs;
452 struct btrfs_device *dev;
453
454 if (!cur_dev->name)
455 return;
456
457 list_for_each_entry(fs_devs, &fs_uuids, list) {
458 int del = 1;
459
460 if (fs_devs->opened)
461 continue;
462 if (fs_devs->seeding)
463 continue;
464
465 list_for_each_entry(dev, &fs_devs->devices, dev_list) {
466
467 if (dev == cur_dev)
468 continue;
469 if (!dev->name)
470 continue;
471
472 /*
473 * Todo: This won't be enough. What if the same device
474 * comes back (with new uuid and) with its mapper path?
475 * But for now, this does help as mostly an admin will
476 * either use mapper or non mapper path throughout.
477 */
478 rcu_read_lock();
479 del = strcmp(rcu_str_deref(dev->name),
480 rcu_str_deref(cur_dev->name));
481 rcu_read_unlock();
482 if (!del)
483 break;
484 }
485
486 if (!del) {
487 /* delete the stale device */
488 if (fs_devs->num_devices == 1) {
489 btrfs_sysfs_remove_fsid(fs_devs);
490 list_del(&fs_devs->list);
491 free_fs_devices(fs_devs);
492 } else {
493 fs_devs->num_devices--;
494 list_del(&dev->dev_list);
495 rcu_string_free(dev->name);
496 kfree(dev);
497 }
498 break;
499 }
500 }
501 }
502
503 /*
504 * Add new device to list of registered devices
505 *
506 * Returns:
507 * 1 - first time device is seen
508 * 0 - device already known
509 * < 0 - error
510 */
511 static noinline int device_list_add(const char *path,
512 struct btrfs_super_block *disk_super,
513 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
514 {
515 struct btrfs_device *device;
516 struct btrfs_fs_devices *fs_devices;
517 struct rcu_string *name;
518 int ret = 0;
519 u64 found_transid = btrfs_super_generation(disk_super);
520
521 fs_devices = find_fsid(disk_super->fsid);
522 if (!fs_devices) {
523 fs_devices = alloc_fs_devices(disk_super->fsid);
524 if (IS_ERR(fs_devices))
525 return PTR_ERR(fs_devices);
526
527 list_add(&fs_devices->list, &fs_uuids);
528
529 device = NULL;
530 } else {
531 device = __find_device(&fs_devices->devices, devid,
532 disk_super->dev_item.uuid);
533 }
534
535 if (!device) {
536 if (fs_devices->opened)
537 return -EBUSY;
538
539 device = btrfs_alloc_device(NULL, &devid,
540 disk_super->dev_item.uuid);
541 if (IS_ERR(device)) {
542 /* we can safely leave the fs_devices entry around */
543 return PTR_ERR(device);
544 }
545
546 name = rcu_string_strdup(path, GFP_NOFS);
547 if (!name) {
548 kfree(device);
549 return -ENOMEM;
550 }
551 rcu_assign_pointer(device->name, name);
552
553 mutex_lock(&fs_devices->device_list_mutex);
554 list_add_rcu(&device->dev_list, &fs_devices->devices);
555 fs_devices->num_devices++;
556 mutex_unlock(&fs_devices->device_list_mutex);
557
558 ret = 1;
559 device->fs_devices = fs_devices;
560 } else if (!device->name || strcmp(device->name->str, path)) {
561 /*
562 * When FS is already mounted.
563 * 1. If you are here and if the device->name is NULL that
564 * means this device was missing at time of FS mount.
565 * 2. If you are here and if the device->name is different
566 * from 'path' that means either
567 * a. The same device disappeared and reappeared with
568 * different name. or
569 * b. The missing-disk-which-was-replaced, has
570 * reappeared now.
571 *
572 * We must allow 1 and 2a above. But 2b would be a spurious
573 * and unintentional.
574 *
575 * Further in case of 1 and 2a above, the disk at 'path'
576 * would have missed some transaction when it was away and
577 * in case of 2a the stale bdev has to be updated as well.
578 * 2b must not be allowed at all time.
579 */
580
581 /*
582 * For now, we do allow update to btrfs_fs_device through the
583 * btrfs dev scan cli after FS has been mounted. We're still
584 * tracking a problem where systems fail mount by subvolume id
585 * when we reject replacement on a mounted FS.
586 */
587 if (!fs_devices->opened && found_transid < device->generation) {
588 /*
589 * That is if the FS is _not_ mounted and if you
590 * are here, that means there is more than one
591 * disk with same uuid and devid.We keep the one
592 * with larger generation number or the last-in if
593 * generation are equal.
594 */
595 return -EEXIST;
596 }
597
598 name = rcu_string_strdup(path, GFP_NOFS);
599 if (!name)
600 return -ENOMEM;
601 rcu_string_free(device->name);
602 rcu_assign_pointer(device->name, name);
603 if (device->missing) {
604 fs_devices->missing_devices--;
605 device->missing = 0;
606 }
607 }
608
609 /*
610 * Unmount does not free the btrfs_device struct but would zero
611 * generation along with most of the other members. So just update
612 * it back. We need it to pick the disk with largest generation
613 * (as above).
614 */
615 if (!fs_devices->opened)
616 device->generation = found_transid;
617
618 /*
619 * if there is new btrfs on an already registered device,
620 * then remove the stale device entry.
621 */
622 btrfs_free_stale_device(device);
623
624 *fs_devices_ret = fs_devices;
625
626 return ret;
627 }
628
629 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
630 {
631 struct btrfs_fs_devices *fs_devices;
632 struct btrfs_device *device;
633 struct btrfs_device *orig_dev;
634
635 fs_devices = alloc_fs_devices(orig->fsid);
636 if (IS_ERR(fs_devices))
637 return fs_devices;
638
639 mutex_lock(&orig->device_list_mutex);
640 fs_devices->total_devices = orig->total_devices;
641
642 /* We have held the volume lock, it is safe to get the devices. */
643 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
644 struct rcu_string *name;
645
646 device = btrfs_alloc_device(NULL, &orig_dev->devid,
647 orig_dev->uuid);
648 if (IS_ERR(device))
649 goto error;
650
651 /*
652 * This is ok to do without rcu read locked because we hold the
653 * uuid mutex so nothing we touch in here is going to disappear.
654 */
655 if (orig_dev->name) {
656 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
657 if (!name) {
658 kfree(device);
659 goto error;
660 }
661 rcu_assign_pointer(device->name, name);
662 }
663
664 list_add(&device->dev_list, &fs_devices->devices);
665 device->fs_devices = fs_devices;
666 fs_devices->num_devices++;
667 }
668 mutex_unlock(&orig->device_list_mutex);
669 return fs_devices;
670 error:
671 mutex_unlock(&orig->device_list_mutex);
672 free_fs_devices(fs_devices);
673 return ERR_PTR(-ENOMEM);
674 }
675
676 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step)
677 {
678 struct btrfs_device *device, *next;
679 struct btrfs_device *latest_dev = NULL;
680
681 mutex_lock(&uuid_mutex);
682 again:
683 /* This is the initialized path, it is safe to release the devices. */
684 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
685 if (device->in_fs_metadata) {
686 if (!device->is_tgtdev_for_dev_replace &&
687 (!latest_dev ||
688 device->generation > latest_dev->generation)) {
689 latest_dev = device;
690 }
691 continue;
692 }
693
694 if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
695 /*
696 * In the first step, keep the device which has
697 * the correct fsid and the devid that is used
698 * for the dev_replace procedure.
699 * In the second step, the dev_replace state is
700 * read from the device tree and it is known
701 * whether the procedure is really active or
702 * not, which means whether this device is
703 * used or whether it should be removed.
704 */
705 if (step == 0 || device->is_tgtdev_for_dev_replace) {
706 continue;
707 }
708 }
709 if (device->bdev) {
710 blkdev_put(device->bdev, device->mode);
711 device->bdev = NULL;
712 fs_devices->open_devices--;
713 }
714 if (device->writeable) {
715 list_del_init(&device->dev_alloc_list);
716 device->writeable = 0;
717 if (!device->is_tgtdev_for_dev_replace)
718 fs_devices->rw_devices--;
719 }
720 list_del_init(&device->dev_list);
721 fs_devices->num_devices--;
722 rcu_string_free(device->name);
723 kfree(device);
724 }
725
726 if (fs_devices->seed) {
727 fs_devices = fs_devices->seed;
728 goto again;
729 }
730
731 fs_devices->latest_bdev = latest_dev->bdev;
732
733 mutex_unlock(&uuid_mutex);
734 }
735
736 static void __free_device(struct work_struct *work)
737 {
738 struct btrfs_device *device;
739
740 device = container_of(work, struct btrfs_device, rcu_work);
741
742 if (device->bdev)
743 blkdev_put(device->bdev, device->mode);
744
745 rcu_string_free(device->name);
746 kfree(device);
747 }
748
749 static void free_device(struct rcu_head *head)
750 {
751 struct btrfs_device *device;
752
753 device = container_of(head, struct btrfs_device, rcu);
754
755 INIT_WORK(&device->rcu_work, __free_device);
756 schedule_work(&device->rcu_work);
757 }
758
759 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
760 {
761 struct btrfs_device *device, *tmp;
762
763 if (--fs_devices->opened > 0)
764 return 0;
765
766 mutex_lock(&fs_devices->device_list_mutex);
767 list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list) {
768 struct btrfs_device *new_device;
769 struct rcu_string *name;
770
771 if (device->bdev)
772 fs_devices->open_devices--;
773
774 if (device->writeable &&
775 device->devid != BTRFS_DEV_REPLACE_DEVID) {
776 list_del_init(&device->dev_alloc_list);
777 fs_devices->rw_devices--;
778 }
779
780 if (device->missing)
781 fs_devices->missing_devices--;
782
783 new_device = btrfs_alloc_device(NULL, &device->devid,
784 device->uuid);
785 BUG_ON(IS_ERR(new_device)); /* -ENOMEM */
786
787 /* Safe because we are under uuid_mutex */
788 if (device->name) {
789 name = rcu_string_strdup(device->name->str, GFP_NOFS);
790 BUG_ON(!name); /* -ENOMEM */
791 rcu_assign_pointer(new_device->name, name);
792 }
793
794 list_replace_rcu(&device->dev_list, &new_device->dev_list);
795 new_device->fs_devices = device->fs_devices;
796
797 call_rcu(&device->rcu, free_device);
798 }
799 mutex_unlock(&fs_devices->device_list_mutex);
800
801 WARN_ON(fs_devices->open_devices);
802 WARN_ON(fs_devices->rw_devices);
803 fs_devices->opened = 0;
804 fs_devices->seeding = 0;
805
806 return 0;
807 }
808
809 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
810 {
811 struct btrfs_fs_devices *seed_devices = NULL;
812 int ret;
813
814 mutex_lock(&uuid_mutex);
815 ret = __btrfs_close_devices(fs_devices);
816 if (!fs_devices->opened) {
817 seed_devices = fs_devices->seed;
818 fs_devices->seed = NULL;
819 }
820 mutex_unlock(&uuid_mutex);
821
822 while (seed_devices) {
823 fs_devices = seed_devices;
824 seed_devices = fs_devices->seed;
825 __btrfs_close_devices(fs_devices);
826 free_fs_devices(fs_devices);
827 }
828 /*
829 * Wait for rcu kworkers under __btrfs_close_devices
830 * to finish all blkdev_puts so device is really
831 * free when umount is done.
832 */
833 rcu_barrier();
834 return ret;
835 }
836
837 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
838 fmode_t flags, void *holder)
839 {
840 struct request_queue *q;
841 struct block_device *bdev;
842 struct list_head *head = &fs_devices->devices;
843 struct btrfs_device *device;
844 struct btrfs_device *latest_dev = NULL;
845 struct buffer_head *bh;
846 struct btrfs_super_block *disk_super;
847 u64 devid;
848 int seeding = 1;
849 int ret = 0;
850
851 flags |= FMODE_EXCL;
852
853 list_for_each_entry(device, head, dev_list) {
854 if (device->bdev)
855 continue;
856 if (!device->name)
857 continue;
858
859 /* Just open everything we can; ignore failures here */
860 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
861 &bdev, &bh))
862 continue;
863
864 disk_super = (struct btrfs_super_block *)bh->b_data;
865 devid = btrfs_stack_device_id(&disk_super->dev_item);
866 if (devid != device->devid)
867 goto error_brelse;
868
869 if (memcmp(device->uuid, disk_super->dev_item.uuid,
870 BTRFS_UUID_SIZE))
871 goto error_brelse;
872
873 device->generation = btrfs_super_generation(disk_super);
874 if (!latest_dev ||
875 device->generation > latest_dev->generation)
876 latest_dev = device;
877
878 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
879 device->writeable = 0;
880 } else {
881 device->writeable = !bdev_read_only(bdev);
882 seeding = 0;
883 }
884
885 q = bdev_get_queue(bdev);
886 if (blk_queue_discard(q))
887 device->can_discard = 1;
888
889 device->bdev = bdev;
890 device->in_fs_metadata = 0;
891 device->mode = flags;
892
893 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
894 fs_devices->rotating = 1;
895
896 fs_devices->open_devices++;
897 if (device->writeable &&
898 device->devid != BTRFS_DEV_REPLACE_DEVID) {
899 fs_devices->rw_devices++;
900 list_add(&device->dev_alloc_list,
901 &fs_devices->alloc_list);
902 }
903 brelse(bh);
904 continue;
905
906 error_brelse:
907 brelse(bh);
908 blkdev_put(bdev, flags);
909 continue;
910 }
911 if (fs_devices->open_devices == 0) {
912 ret = -EINVAL;
913 goto out;
914 }
915 fs_devices->seeding = seeding;
916 fs_devices->opened = 1;
917 fs_devices->latest_bdev = latest_dev->bdev;
918 fs_devices->total_rw_bytes = 0;
919 out:
920 return ret;
921 }
922
923 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
924 fmode_t flags, void *holder)
925 {
926 int ret;
927
928 mutex_lock(&uuid_mutex);
929 if (fs_devices->opened) {
930 fs_devices->opened++;
931 ret = 0;
932 } else {
933 ret = __btrfs_open_devices(fs_devices, flags, holder);
934 }
935 mutex_unlock(&uuid_mutex);
936 return ret;
937 }
938
939 /*
940 * Look for a btrfs signature on a device. This may be called out of the mount path
941 * and we are not allowed to call set_blocksize during the scan. The superblock
942 * is read via pagecache
943 */
944 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
945 struct btrfs_fs_devices **fs_devices_ret)
946 {
947 struct btrfs_super_block *disk_super;
948 struct block_device *bdev;
949 struct page *page;
950 void *p;
951 int ret = -EINVAL;
952 u64 devid;
953 u64 transid;
954 u64 total_devices;
955 u64 bytenr;
956 pgoff_t index;
957
958 /*
959 * we would like to check all the supers, but that would make
960 * a btrfs mount succeed after a mkfs from a different FS.
961 * So, we need to add a special mount option to scan for
962 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
963 */
964 bytenr = btrfs_sb_offset(0);
965 flags |= FMODE_EXCL;
966 mutex_lock(&uuid_mutex);
967
968 bdev = blkdev_get_by_path(path, flags, holder);
969
970 if (IS_ERR(bdev)) {
971 ret = PTR_ERR(bdev);
972 goto error;
973 }
974
975 /* make sure our super fits in the device */
976 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode))
977 goto error_bdev_put;
978
979 /* make sure our super fits in the page */
980 if (sizeof(*disk_super) > PAGE_CACHE_SIZE)
981 goto error_bdev_put;
982
983 /* make sure our super doesn't straddle pages on disk */
984 index = bytenr >> PAGE_CACHE_SHIFT;
985 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index)
986 goto error_bdev_put;
987
988 /* pull in the page with our super */
989 page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
990 index, GFP_NOFS);
991
992 if (IS_ERR_OR_NULL(page))
993 goto error_bdev_put;
994
995 p = kmap(page);
996
997 /* align our pointer to the offset of the super block */
998 disk_super = p + (bytenr & ~PAGE_CACHE_MASK);
999
1000 if (btrfs_super_bytenr(disk_super) != bytenr ||
1001 btrfs_super_magic(disk_super) != BTRFS_MAGIC)
1002 goto error_unmap;
1003
1004 devid = btrfs_stack_device_id(&disk_super->dev_item);
1005 transid = btrfs_super_generation(disk_super);
1006 total_devices = btrfs_super_num_devices(disk_super);
1007
1008 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
1009 if (ret > 0) {
1010 if (disk_super->label[0]) {
1011 if (disk_super->label[BTRFS_LABEL_SIZE - 1])
1012 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
1013 printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
1014 } else {
1015 printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
1016 }
1017
1018 printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
1019 ret = 0;
1020 }
1021 if (!ret && fs_devices_ret)
1022 (*fs_devices_ret)->total_devices = total_devices;
1023
1024 error_unmap:
1025 kunmap(page);
1026 page_cache_release(page);
1027
1028 error_bdev_put:
1029 blkdev_put(bdev, flags);
1030 error:
1031 mutex_unlock(&uuid_mutex);
1032 return ret;
1033 }
1034
1035 /* helper to account the used device space in the range */
1036 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
1037 u64 end, u64 *length)
1038 {
1039 struct btrfs_key key;
1040 struct btrfs_root *root = device->dev_root;
1041 struct btrfs_dev_extent *dev_extent;
1042 struct btrfs_path *path;
1043 u64 extent_end;
1044 int ret;
1045 int slot;
1046 struct extent_buffer *l;
1047
1048 *length = 0;
1049
1050 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
1051 return 0;
1052
1053 path = btrfs_alloc_path();
1054 if (!path)
1055 return -ENOMEM;
1056 path->reada = 2;
1057
1058 key.objectid = device->devid;
1059 key.offset = start;
1060 key.type = BTRFS_DEV_EXTENT_KEY;
1061
1062 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1063 if (ret < 0)
1064 goto out;
1065 if (ret > 0) {
1066 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1067 if (ret < 0)
1068 goto out;
1069 }
1070
1071 while (1) {
1072 l = path->nodes[0];
1073 slot = path->slots[0];
1074 if (slot >= btrfs_header_nritems(l)) {
1075 ret = btrfs_next_leaf(root, path);
1076 if (ret == 0)
1077 continue;
1078 if (ret < 0)
1079 goto out;
1080
1081 break;
1082 }
1083 btrfs_item_key_to_cpu(l, &key, slot);
1084
1085 if (key.objectid < device->devid)
1086 goto next;
1087
1088 if (key.objectid > device->devid)
1089 break;
1090
1091 if (key.type != BTRFS_DEV_EXTENT_KEY)
1092 goto next;
1093
1094 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1095 extent_end = key.offset + btrfs_dev_extent_length(l,
1096 dev_extent);
1097 if (key.offset <= start && extent_end > end) {
1098 *length = end - start + 1;
1099 break;
1100 } else if (key.offset <= start && extent_end > start)
1101 *length += extent_end - start;
1102 else if (key.offset > start && extent_end <= end)
1103 *length += extent_end - key.offset;
1104 else if (key.offset > start && key.offset <= end) {
1105 *length += end - key.offset + 1;
1106 break;
1107 } else if (key.offset > end)
1108 break;
1109
1110 next:
1111 path->slots[0]++;
1112 }
1113 ret = 0;
1114 out:
1115 btrfs_free_path(path);
1116 return ret;
1117 }
1118
1119 static int contains_pending_extent(struct btrfs_transaction *transaction,
1120 struct btrfs_device *device,
1121 u64 *start, u64 len)
1122 {
1123 struct btrfs_fs_info *fs_info = device->dev_root->fs_info;
1124 struct extent_map *em;
1125 struct list_head *search_list = &fs_info->pinned_chunks;
1126 int ret = 0;
1127 u64 physical_start = *start;
1128
1129 if (transaction)
1130 search_list = &transaction->pending_chunks;
1131 again:
1132 list_for_each_entry(em, search_list, list) {
1133 struct map_lookup *map;
1134 int i;
1135
1136 map = (struct map_lookup *)em->bdev;
1137 for (i = 0; i < map->num_stripes; i++) {
1138 u64 end;
1139
1140 if (map->stripes[i].dev != device)
1141 continue;
1142 if (map->stripes[i].physical >= physical_start + len ||
1143 map->stripes[i].physical + em->orig_block_len <=
1144 physical_start)
1145 continue;
1146 /*
1147 * Make sure that while processing the pinned list we do
1148 * not override our *start with a lower value, because
1149 * we can have pinned chunks that fall within this
1150 * device hole and that have lower physical addresses
1151 * than the pending chunks we processed before. If we
1152 * do not take this special care we can end up getting
1153 * 2 pending chunks that start at the same physical
1154 * device offsets because the end offset of a pinned
1155 * chunk can be equal to the start offset of some
1156 * pending chunk.
1157 */
1158 end = map->stripes[i].physical + em->orig_block_len;
1159 if (end > *start) {
1160 *start = end;
1161 ret = 1;
1162 }
1163 }
1164 }
1165 if (search_list != &fs_info->pinned_chunks) {
1166 search_list = &fs_info->pinned_chunks;
1167 goto again;
1168 }
1169
1170 return ret;
1171 }
1172
1173
1174 /*
1175 * find_free_dev_extent_start - find free space in the specified device
1176 * @device: the device which we search the free space in
1177 * @num_bytes: the size of the free space that we need
1178 * @search_start: the position from which to begin the search
1179 * @start: store the start of the free space.
1180 * @len: the size of the free space. that we find, or the size
1181 * of the max free space if we don't find suitable free space
1182 *
1183 * this uses a pretty simple search, the expectation is that it is
1184 * called very infrequently and that a given device has a small number
1185 * of extents
1186 *
1187 * @start is used to store the start of the free space if we find. But if we
1188 * don't find suitable free space, it will be used to store the start position
1189 * of the max free space.
1190 *
1191 * @len is used to store the size of the free space that we find.
1192 * But if we don't find suitable free space, it is used to store the size of
1193 * the max free space.
1194 */
1195 int find_free_dev_extent_start(struct btrfs_transaction *transaction,
1196 struct btrfs_device *device, u64 num_bytes,
1197 u64 search_start, u64 *start, u64 *len)
1198 {
1199 struct btrfs_key key;
1200 struct btrfs_root *root = device->dev_root;
1201 struct btrfs_dev_extent *dev_extent;
1202 struct btrfs_path *path;
1203 u64 hole_size;
1204 u64 max_hole_start;
1205 u64 max_hole_size;
1206 u64 extent_end;
1207 u64 search_end = device->total_bytes;
1208 int ret;
1209 int slot;
1210 struct extent_buffer *l;
1211
1212 path = btrfs_alloc_path();
1213 if (!path)
1214 return -ENOMEM;
1215
1216 max_hole_start = search_start;
1217 max_hole_size = 0;
1218
1219 again:
1220 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
1221 ret = -ENOSPC;
1222 goto out;
1223 }
1224
1225 path->reada = 2;
1226 path->search_commit_root = 1;
1227 path->skip_locking = 1;
1228
1229 key.objectid = device->devid;
1230 key.offset = search_start;
1231 key.type = BTRFS_DEV_EXTENT_KEY;
1232
1233 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1234 if (ret < 0)
1235 goto out;
1236 if (ret > 0) {
1237 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1238 if (ret < 0)
1239 goto out;
1240 }
1241
1242 while (1) {
1243 l = path->nodes[0];
1244 slot = path->slots[0];
1245 if (slot >= btrfs_header_nritems(l)) {
1246 ret = btrfs_next_leaf(root, path);
1247 if (ret == 0)
1248 continue;
1249 if (ret < 0)
1250 goto out;
1251
1252 break;
1253 }
1254 btrfs_item_key_to_cpu(l, &key, slot);
1255
1256 if (key.objectid < device->devid)
1257 goto next;
1258
1259 if (key.objectid > device->devid)
1260 break;
1261
1262 if (key.type != BTRFS_DEV_EXTENT_KEY)
1263 goto next;
1264
1265 if (key.offset > search_start) {
1266 hole_size = key.offset - search_start;
1267
1268 /*
1269 * Have to check before we set max_hole_start, otherwise
1270 * we could end up sending back this offset anyway.
1271 */
1272 if (contains_pending_extent(transaction, device,
1273 &search_start,
1274 hole_size)) {
1275 if (key.offset >= search_start) {
1276 hole_size = key.offset - search_start;
1277 } else {
1278 WARN_ON_ONCE(1);
1279 hole_size = 0;
1280 }
1281 }
1282
1283 if (hole_size > max_hole_size) {
1284 max_hole_start = search_start;
1285 max_hole_size = hole_size;
1286 }
1287
1288 /*
1289 * If this free space is greater than which we need,
1290 * it must be the max free space that we have found
1291 * until now, so max_hole_start must point to the start
1292 * of this free space and the length of this free space
1293 * is stored in max_hole_size. Thus, we return
1294 * max_hole_start and max_hole_size and go back to the
1295 * caller.
1296 */
1297 if (hole_size >= num_bytes) {
1298 ret = 0;
1299 goto out;
1300 }
1301 }
1302
1303 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1304 extent_end = key.offset + btrfs_dev_extent_length(l,
1305 dev_extent);
1306 if (extent_end > search_start)
1307 search_start = extent_end;
1308 next:
1309 path->slots[0]++;
1310 cond_resched();
1311 }
1312
1313 /*
1314 * At this point, search_start should be the end of
1315 * allocated dev extents, and when shrinking the device,
1316 * search_end may be smaller than search_start.
1317 */
1318 if (search_end > search_start) {
1319 hole_size = search_end - search_start;
1320
1321 if (contains_pending_extent(transaction, device, &search_start,
1322 hole_size)) {
1323 btrfs_release_path(path);
1324 goto again;
1325 }
1326
1327 if (hole_size > max_hole_size) {
1328 max_hole_start = search_start;
1329 max_hole_size = hole_size;
1330 }
1331 }
1332
1333 /* See above. */
1334 if (max_hole_size < num_bytes)
1335 ret = -ENOSPC;
1336 else
1337 ret = 0;
1338
1339 out:
1340 btrfs_free_path(path);
1341 *start = max_hole_start;
1342 if (len)
1343 *len = max_hole_size;
1344 return ret;
1345 }
1346
1347 int find_free_dev_extent(struct btrfs_trans_handle *trans,
1348 struct btrfs_device *device, u64 num_bytes,
1349 u64 *start, u64 *len)
1350 {
1351 struct btrfs_root *root = device->dev_root;
1352 u64 search_start;
1353
1354 /* FIXME use last free of some kind */
1355
1356 /*
1357 * we don't want to overwrite the superblock on the drive,
1358 * so we make sure to start at an offset of at least 1MB
1359 */
1360 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
1361 return find_free_dev_extent_start(trans->transaction, device,
1362 num_bytes, search_start, start, len);
1363 }
1364
1365 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1366 struct btrfs_device *device,
1367 u64 start, u64 *dev_extent_len)
1368 {
1369 int ret;
1370 struct btrfs_path *path;
1371 struct btrfs_root *root = device->dev_root;
1372 struct btrfs_key key;
1373 struct btrfs_key found_key;
1374 struct extent_buffer *leaf = NULL;
1375 struct btrfs_dev_extent *extent = NULL;
1376
1377 path = btrfs_alloc_path();
1378 if (!path)
1379 return -ENOMEM;
1380
1381 key.objectid = device->devid;
1382 key.offset = start;
1383 key.type = BTRFS_DEV_EXTENT_KEY;
1384 again:
1385 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1386 if (ret > 0) {
1387 ret = btrfs_previous_item(root, path, key.objectid,
1388 BTRFS_DEV_EXTENT_KEY);
1389 if (ret)
1390 goto out;
1391 leaf = path->nodes[0];
1392 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1393 extent = btrfs_item_ptr(leaf, path->slots[0],
1394 struct btrfs_dev_extent);
1395 BUG_ON(found_key.offset > start || found_key.offset +
1396 btrfs_dev_extent_length(leaf, extent) < start);
1397 key = found_key;
1398 btrfs_release_path(path);
1399 goto again;
1400 } else if (ret == 0) {
1401 leaf = path->nodes[0];
1402 extent = btrfs_item_ptr(leaf, path->slots[0],
1403 struct btrfs_dev_extent);
1404 } else {
1405 btrfs_error(root->fs_info, ret, "Slot search failed");
1406 goto out;
1407 }
1408
1409 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1410
1411 ret = btrfs_del_item(trans, root, path);
1412 if (ret) {
1413 btrfs_error(root->fs_info, ret,
1414 "Failed to remove dev extent item");
1415 } else {
1416 trans->transaction->have_free_bgs = 1;
1417 }
1418 out:
1419 btrfs_free_path(path);
1420 return ret;
1421 }
1422
1423 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1424 struct btrfs_device *device,
1425 u64 chunk_tree, u64 chunk_objectid,
1426 u64 chunk_offset, u64 start, u64 num_bytes)
1427 {
1428 int ret;
1429 struct btrfs_path *path;
1430 struct btrfs_root *root = device->dev_root;
1431 struct btrfs_dev_extent *extent;
1432 struct extent_buffer *leaf;
1433 struct btrfs_key key;
1434
1435 WARN_ON(!device->in_fs_metadata);
1436 WARN_ON(device->is_tgtdev_for_dev_replace);
1437 path = btrfs_alloc_path();
1438 if (!path)
1439 return -ENOMEM;
1440
1441 key.objectid = device->devid;
1442 key.offset = start;
1443 key.type = BTRFS_DEV_EXTENT_KEY;
1444 ret = btrfs_insert_empty_item(trans, root, path, &key,
1445 sizeof(*extent));
1446 if (ret)
1447 goto out;
1448
1449 leaf = path->nodes[0];
1450 extent = btrfs_item_ptr(leaf, path->slots[0],
1451 struct btrfs_dev_extent);
1452 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1453 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1454 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1455
1456 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1457 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE);
1458
1459 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1460 btrfs_mark_buffer_dirty(leaf);
1461 out:
1462 btrfs_free_path(path);
1463 return ret;
1464 }
1465
1466 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1467 {
1468 struct extent_map_tree *em_tree;
1469 struct extent_map *em;
1470 struct rb_node *n;
1471 u64 ret = 0;
1472
1473 em_tree = &fs_info->mapping_tree.map_tree;
1474 read_lock(&em_tree->lock);
1475 n = rb_last(&em_tree->map);
1476 if (n) {
1477 em = rb_entry(n, struct extent_map, rb_node);
1478 ret = em->start + em->len;
1479 }
1480 read_unlock(&em_tree->lock);
1481
1482 return ret;
1483 }
1484
1485 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1486 u64 *devid_ret)
1487 {
1488 int ret;
1489 struct btrfs_key key;
1490 struct btrfs_key found_key;
1491 struct btrfs_path *path;
1492
1493 path = btrfs_alloc_path();
1494 if (!path)
1495 return -ENOMEM;
1496
1497 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1498 key.type = BTRFS_DEV_ITEM_KEY;
1499 key.offset = (u64)-1;
1500
1501 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1502 if (ret < 0)
1503 goto error;
1504
1505 BUG_ON(ret == 0); /* Corruption */
1506
1507 ret = btrfs_previous_item(fs_info->chunk_root, path,
1508 BTRFS_DEV_ITEMS_OBJECTID,
1509 BTRFS_DEV_ITEM_KEY);
1510 if (ret) {
1511 *devid_ret = 1;
1512 } else {
1513 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1514 path->slots[0]);
1515 *devid_ret = found_key.offset + 1;
1516 }
1517 ret = 0;
1518 error:
1519 btrfs_free_path(path);
1520 return ret;
1521 }
1522
1523 /*
1524 * the device information is stored in the chunk root
1525 * the btrfs_device struct should be fully filled in
1526 */
1527 static int btrfs_add_device(struct btrfs_trans_handle *trans,
1528 struct btrfs_root *root,
1529 struct btrfs_device *device)
1530 {
1531 int ret;
1532 struct btrfs_path *path;
1533 struct btrfs_dev_item *dev_item;
1534 struct extent_buffer *leaf;
1535 struct btrfs_key key;
1536 unsigned long ptr;
1537
1538 root = root->fs_info->chunk_root;
1539
1540 path = btrfs_alloc_path();
1541 if (!path)
1542 return -ENOMEM;
1543
1544 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1545 key.type = BTRFS_DEV_ITEM_KEY;
1546 key.offset = device->devid;
1547
1548 ret = btrfs_insert_empty_item(trans, root, path, &key,
1549 sizeof(*dev_item));
1550 if (ret)
1551 goto out;
1552
1553 leaf = path->nodes[0];
1554 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1555
1556 btrfs_set_device_id(leaf, dev_item, device->devid);
1557 btrfs_set_device_generation(leaf, dev_item, 0);
1558 btrfs_set_device_type(leaf, dev_item, device->type);
1559 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1560 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1561 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1562 btrfs_set_device_total_bytes(leaf, dev_item,
1563 btrfs_device_get_disk_total_bytes(device));
1564 btrfs_set_device_bytes_used(leaf, dev_item,
1565 btrfs_device_get_bytes_used(device));
1566 btrfs_set_device_group(leaf, dev_item, 0);
1567 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1568 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1569 btrfs_set_device_start_offset(leaf, dev_item, 0);
1570
1571 ptr = btrfs_device_uuid(dev_item);
1572 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1573 ptr = btrfs_device_fsid(dev_item);
1574 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1575 btrfs_mark_buffer_dirty(leaf);
1576
1577 ret = 0;
1578 out:
1579 btrfs_free_path(path);
1580 return ret;
1581 }
1582
1583 /*
1584 * Function to update ctime/mtime for a given device path.
1585 * Mainly used for ctime/mtime based probe like libblkid.
1586 */
1587 static void update_dev_time(char *path_name)
1588 {
1589 struct file *filp;
1590
1591 filp = filp_open(path_name, O_RDWR, 0);
1592 if (IS_ERR(filp))
1593 return;
1594 file_update_time(filp);
1595 filp_close(filp, NULL);
1596 return;
1597 }
1598
1599 static int btrfs_rm_dev_item(struct btrfs_root *root,
1600 struct btrfs_device *device)
1601 {
1602 int ret;
1603 struct btrfs_path *path;
1604 struct btrfs_key key;
1605 struct btrfs_trans_handle *trans;
1606
1607 root = root->fs_info->chunk_root;
1608
1609 path = btrfs_alloc_path();
1610 if (!path)
1611 return -ENOMEM;
1612
1613 trans = btrfs_start_transaction(root, 0);
1614 if (IS_ERR(trans)) {
1615 btrfs_free_path(path);
1616 return PTR_ERR(trans);
1617 }
1618 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1619 key.type = BTRFS_DEV_ITEM_KEY;
1620 key.offset = device->devid;
1621
1622 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1623 if (ret < 0)
1624 goto out;
1625
1626 if (ret > 0) {
1627 ret = -ENOENT;
1628 goto out;
1629 }
1630
1631 ret = btrfs_del_item(trans, root, path);
1632 if (ret)
1633 goto out;
1634 out:
1635 btrfs_free_path(path);
1636 btrfs_commit_transaction(trans, root);
1637 return ret;
1638 }
1639
1640 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1641 {
1642 struct btrfs_device *device;
1643 struct btrfs_device *next_device;
1644 struct block_device *bdev;
1645 struct buffer_head *bh = NULL;
1646 struct btrfs_super_block *disk_super;
1647 struct btrfs_fs_devices *cur_devices;
1648 u64 all_avail;
1649 u64 devid;
1650 u64 num_devices;
1651 u8 *dev_uuid;
1652 unsigned seq;
1653 int ret = 0;
1654 bool clear_super = false;
1655
1656 mutex_lock(&uuid_mutex);
1657
1658 do {
1659 seq = read_seqbegin(&root->fs_info->profiles_lock);
1660
1661 all_avail = root->fs_info->avail_data_alloc_bits |
1662 root->fs_info->avail_system_alloc_bits |
1663 root->fs_info->avail_metadata_alloc_bits;
1664 } while (read_seqretry(&root->fs_info->profiles_lock, seq));
1665
1666 num_devices = root->fs_info->fs_devices->num_devices;
1667 btrfs_dev_replace_lock(&root->fs_info->dev_replace);
1668 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1669 WARN_ON(num_devices < 1);
1670 num_devices--;
1671 }
1672 btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
1673
1674 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
1675 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
1676 goto out;
1677 }
1678
1679 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
1680 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
1681 goto out;
1682 }
1683
1684 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
1685 root->fs_info->fs_devices->rw_devices <= 2) {
1686 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
1687 goto out;
1688 }
1689 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
1690 root->fs_info->fs_devices->rw_devices <= 3) {
1691 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
1692 goto out;
1693 }
1694
1695 if (strcmp(device_path, "missing") == 0) {
1696 struct list_head *devices;
1697 struct btrfs_device *tmp;
1698
1699 device = NULL;
1700 devices = &root->fs_info->fs_devices->devices;
1701 /*
1702 * It is safe to read the devices since the volume_mutex
1703 * is held.
1704 */
1705 list_for_each_entry(tmp, devices, dev_list) {
1706 if (tmp->in_fs_metadata &&
1707 !tmp->is_tgtdev_for_dev_replace &&
1708 !tmp->bdev) {
1709 device = tmp;
1710 break;
1711 }
1712 }
1713 bdev = NULL;
1714 bh = NULL;
1715 disk_super = NULL;
1716 if (!device) {
1717 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
1718 goto out;
1719 }
1720 } else {
1721 ret = btrfs_get_bdev_and_sb(device_path,
1722 FMODE_WRITE | FMODE_EXCL,
1723 root->fs_info->bdev_holder, 0,
1724 &bdev, &bh);
1725 if (ret)
1726 goto out;
1727 disk_super = (struct btrfs_super_block *)bh->b_data;
1728 devid = btrfs_stack_device_id(&disk_super->dev_item);
1729 dev_uuid = disk_super->dev_item.uuid;
1730 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1731 disk_super->fsid);
1732 if (!device) {
1733 ret = -ENOENT;
1734 goto error_brelse;
1735 }
1736 }
1737
1738 if (device->is_tgtdev_for_dev_replace) {
1739 ret = BTRFS_ERROR_DEV_TGT_REPLACE;
1740 goto error_brelse;
1741 }
1742
1743 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1744 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
1745 goto error_brelse;
1746 }
1747
1748 if (device->writeable) {
1749 lock_chunks(root);
1750 list_del_init(&device->dev_alloc_list);
1751 device->fs_devices->rw_devices--;
1752 unlock_chunks(root);
1753 clear_super = true;
1754 }
1755
1756 mutex_unlock(&uuid_mutex);
1757 ret = btrfs_shrink_device(device, 0);
1758 mutex_lock(&uuid_mutex);
1759 if (ret)
1760 goto error_undo;
1761
1762 /*
1763 * TODO: the superblock still includes this device in its num_devices
1764 * counter although write_all_supers() is not locked out. This
1765 * could give a filesystem state which requires a degraded mount.
1766 */
1767 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1768 if (ret)
1769 goto error_undo;
1770
1771 device->in_fs_metadata = 0;
1772 btrfs_scrub_cancel_dev(root->fs_info, device);
1773
1774 /*
1775 * the device list mutex makes sure that we don't change
1776 * the device list while someone else is writing out all
1777 * the device supers. Whoever is writing all supers, should
1778 * lock the device list mutex before getting the number of
1779 * devices in the super block (super_copy). Conversely,
1780 * whoever updates the number of devices in the super block
1781 * (super_copy) should hold the device list mutex.
1782 */
1783
1784 cur_devices = device->fs_devices;
1785 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1786 list_del_rcu(&device->dev_list);
1787
1788 device->fs_devices->num_devices--;
1789 device->fs_devices->total_devices--;
1790
1791 if (device->missing)
1792 device->fs_devices->missing_devices--;
1793
1794 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1795 struct btrfs_device, dev_list);
1796 if (device->bdev == root->fs_info->sb->s_bdev)
1797 root->fs_info->sb->s_bdev = next_device->bdev;
1798 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1799 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1800
1801 if (device->bdev) {
1802 device->fs_devices->open_devices--;
1803 /* remove sysfs entry */
1804 btrfs_kobj_rm_device(root->fs_info->fs_devices, device);
1805 }
1806
1807 call_rcu(&device->rcu, free_device);
1808
1809 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1810 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1811 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1812
1813 if (cur_devices->open_devices == 0) {
1814 struct btrfs_fs_devices *fs_devices;
1815 fs_devices = root->fs_info->fs_devices;
1816 while (fs_devices) {
1817 if (fs_devices->seed == cur_devices) {
1818 fs_devices->seed = cur_devices->seed;
1819 break;
1820 }
1821 fs_devices = fs_devices->seed;
1822 }
1823 cur_devices->seed = NULL;
1824 __btrfs_close_devices(cur_devices);
1825 free_fs_devices(cur_devices);
1826 }
1827
1828 root->fs_info->num_tolerated_disk_barrier_failures =
1829 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1830
1831 /*
1832 * at this point, the device is zero sized. We want to
1833 * remove it from the devices list and zero out the old super
1834 */
1835 if (clear_super && disk_super) {
1836 u64 bytenr;
1837 int i;
1838
1839 /* make sure this device isn't detected as part of
1840 * the FS anymore
1841 */
1842 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1843 set_buffer_dirty(bh);
1844 sync_dirty_buffer(bh);
1845
1846 /* clear the mirror copies of super block on the disk
1847 * being removed, 0th copy is been taken care above and
1848 * the below would take of the rest
1849 */
1850 for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1851 bytenr = btrfs_sb_offset(i);
1852 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
1853 i_size_read(bdev->bd_inode))
1854 break;
1855
1856 brelse(bh);
1857 bh = __bread(bdev, bytenr / 4096,
1858 BTRFS_SUPER_INFO_SIZE);
1859 if (!bh)
1860 continue;
1861
1862 disk_super = (struct btrfs_super_block *)bh->b_data;
1863
1864 if (btrfs_super_bytenr(disk_super) != bytenr ||
1865 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1866 continue;
1867 }
1868 memset(&disk_super->magic, 0,
1869 sizeof(disk_super->magic));
1870 set_buffer_dirty(bh);
1871 sync_dirty_buffer(bh);
1872 }
1873 }
1874
1875 ret = 0;
1876
1877 if (bdev) {
1878 /* Notify udev that device has changed */
1879 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
1880
1881 /* Update ctime/mtime for device path for libblkid */
1882 update_dev_time(device_path);
1883 }
1884
1885 error_brelse:
1886 brelse(bh);
1887 if (bdev)
1888 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1889 out:
1890 mutex_unlock(&uuid_mutex);
1891 return ret;
1892 error_undo:
1893 if (device->writeable) {
1894 lock_chunks(root);
1895 list_add(&device->dev_alloc_list,
1896 &root->fs_info->fs_devices->alloc_list);
1897 device->fs_devices->rw_devices++;
1898 unlock_chunks(root);
1899 }
1900 goto error_brelse;
1901 }
1902
1903 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
1904 struct btrfs_device *srcdev)
1905 {
1906 struct btrfs_fs_devices *fs_devices;
1907
1908 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1909
1910 /*
1911 * in case of fs with no seed, srcdev->fs_devices will point
1912 * to fs_devices of fs_info. However when the dev being replaced is
1913 * a seed dev it will point to the seed's local fs_devices. In short
1914 * srcdev will have its correct fs_devices in both the cases.
1915 */
1916 fs_devices = srcdev->fs_devices;
1917
1918 list_del_rcu(&srcdev->dev_list);
1919 list_del_rcu(&srcdev->dev_alloc_list);
1920 fs_devices->num_devices--;
1921 if (srcdev->missing)
1922 fs_devices->missing_devices--;
1923
1924 if (srcdev->writeable) {
1925 fs_devices->rw_devices--;
1926 /* zero out the old super if it is writable */
1927 btrfs_scratch_superblock(srcdev);
1928 }
1929
1930 if (srcdev->bdev)
1931 fs_devices->open_devices--;
1932 }
1933
1934 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
1935 struct btrfs_device *srcdev)
1936 {
1937 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
1938
1939 call_rcu(&srcdev->rcu, free_device);
1940
1941 /*
1942 * unless fs_devices is seed fs, num_devices shouldn't go
1943 * zero
1944 */
1945 BUG_ON(!fs_devices->num_devices && !fs_devices->seeding);
1946
1947 /* if this is no devs we rather delete the fs_devices */
1948 if (!fs_devices->num_devices) {
1949 struct btrfs_fs_devices *tmp_fs_devices;
1950
1951 tmp_fs_devices = fs_info->fs_devices;
1952 while (tmp_fs_devices) {
1953 if (tmp_fs_devices->seed == fs_devices) {
1954 tmp_fs_devices->seed = fs_devices->seed;
1955 break;
1956 }
1957 tmp_fs_devices = tmp_fs_devices->seed;
1958 }
1959 fs_devices->seed = NULL;
1960 __btrfs_close_devices(fs_devices);
1961 free_fs_devices(fs_devices);
1962 }
1963 }
1964
1965 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
1966 struct btrfs_device *tgtdev)
1967 {
1968 struct btrfs_device *next_device;
1969
1970 mutex_lock(&uuid_mutex);
1971 WARN_ON(!tgtdev);
1972 mutex_lock(&fs_info->fs_devices->device_list_mutex);
1973
1974 btrfs_kobj_rm_device(fs_info->fs_devices, tgtdev);
1975
1976 if (tgtdev->bdev) {
1977 btrfs_scratch_superblock(tgtdev);
1978 fs_info->fs_devices->open_devices--;
1979 }
1980 fs_info->fs_devices->num_devices--;
1981
1982 next_device = list_entry(fs_info->fs_devices->devices.next,
1983 struct btrfs_device, dev_list);
1984 if (tgtdev->bdev == fs_info->sb->s_bdev)
1985 fs_info->sb->s_bdev = next_device->bdev;
1986 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
1987 fs_info->fs_devices->latest_bdev = next_device->bdev;
1988 list_del_rcu(&tgtdev->dev_list);
1989
1990 call_rcu(&tgtdev->rcu, free_device);
1991
1992 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
1993 mutex_unlock(&uuid_mutex);
1994 }
1995
1996 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
1997 struct btrfs_device **device)
1998 {
1999 int ret = 0;
2000 struct btrfs_super_block *disk_super;
2001 u64 devid;
2002 u8 *dev_uuid;
2003 struct block_device *bdev;
2004 struct buffer_head *bh;
2005
2006 *device = NULL;
2007 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ,
2008 root->fs_info->bdev_holder, 0, &bdev, &bh);
2009 if (ret)
2010 return ret;
2011 disk_super = (struct btrfs_super_block *)bh->b_data;
2012 devid = btrfs_stack_device_id(&disk_super->dev_item);
2013 dev_uuid = disk_super->dev_item.uuid;
2014 *device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2015 disk_super->fsid);
2016 brelse(bh);
2017 if (!*device)
2018 ret = -ENOENT;
2019 blkdev_put(bdev, FMODE_READ);
2020 return ret;
2021 }
2022
2023 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
2024 char *device_path,
2025 struct btrfs_device **device)
2026 {
2027 *device = NULL;
2028 if (strcmp(device_path, "missing") == 0) {
2029 struct list_head *devices;
2030 struct btrfs_device *tmp;
2031
2032 devices = &root->fs_info->fs_devices->devices;
2033 /*
2034 * It is safe to read the devices since the volume_mutex
2035 * is held by the caller.
2036 */
2037 list_for_each_entry(tmp, devices, dev_list) {
2038 if (tmp->in_fs_metadata && !tmp->bdev) {
2039 *device = tmp;
2040 break;
2041 }
2042 }
2043
2044 if (!*device) {
2045 btrfs_err(root->fs_info, "no missing device found");
2046 return -ENOENT;
2047 }
2048
2049 return 0;
2050 } else {
2051 return btrfs_find_device_by_path(root, device_path, device);
2052 }
2053 }
2054
2055 /*
2056 * does all the dirty work required for changing file system's UUID.
2057 */
2058 static int btrfs_prepare_sprout(struct btrfs_root *root)
2059 {
2060 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2061 struct btrfs_fs_devices *old_devices;
2062 struct btrfs_fs_devices *seed_devices;
2063 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
2064 struct btrfs_device *device;
2065 u64 super_flags;
2066
2067 BUG_ON(!mutex_is_locked(&uuid_mutex));
2068 if (!fs_devices->seeding)
2069 return -EINVAL;
2070
2071 seed_devices = __alloc_fs_devices();
2072 if (IS_ERR(seed_devices))
2073 return PTR_ERR(seed_devices);
2074
2075 old_devices = clone_fs_devices(fs_devices);
2076 if (IS_ERR(old_devices)) {
2077 kfree(seed_devices);
2078 return PTR_ERR(old_devices);
2079 }
2080
2081 list_add(&old_devices->list, &fs_uuids);
2082
2083 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
2084 seed_devices->opened = 1;
2085 INIT_LIST_HEAD(&seed_devices->devices);
2086 INIT_LIST_HEAD(&seed_devices->alloc_list);
2087 mutex_init(&seed_devices->device_list_mutex);
2088
2089 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2090 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
2091 synchronize_rcu);
2092 list_for_each_entry(device, &seed_devices->devices, dev_list)
2093 device->fs_devices = seed_devices;
2094
2095 lock_chunks(root);
2096 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
2097 unlock_chunks(root);
2098
2099 fs_devices->seeding = 0;
2100 fs_devices->num_devices = 0;
2101 fs_devices->open_devices = 0;
2102 fs_devices->missing_devices = 0;
2103 fs_devices->rotating = 0;
2104 fs_devices->seed = seed_devices;
2105
2106 generate_random_uuid(fs_devices->fsid);
2107 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2108 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2109 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2110
2111 super_flags = btrfs_super_flags(disk_super) &
2112 ~BTRFS_SUPER_FLAG_SEEDING;
2113 btrfs_set_super_flags(disk_super, super_flags);
2114
2115 return 0;
2116 }
2117
2118 /*
2119 * strore the expected generation for seed devices in device items.
2120 */
2121 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
2122 struct btrfs_root *root)
2123 {
2124 struct btrfs_path *path;
2125 struct extent_buffer *leaf;
2126 struct btrfs_dev_item *dev_item;
2127 struct btrfs_device *device;
2128 struct btrfs_key key;
2129 u8 fs_uuid[BTRFS_UUID_SIZE];
2130 u8 dev_uuid[BTRFS_UUID_SIZE];
2131 u64 devid;
2132 int ret;
2133
2134 path = btrfs_alloc_path();
2135 if (!path)
2136 return -ENOMEM;
2137
2138 root = root->fs_info->chunk_root;
2139 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2140 key.offset = 0;
2141 key.type = BTRFS_DEV_ITEM_KEY;
2142
2143 while (1) {
2144 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2145 if (ret < 0)
2146 goto error;
2147
2148 leaf = path->nodes[0];
2149 next_slot:
2150 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2151 ret = btrfs_next_leaf(root, path);
2152 if (ret > 0)
2153 break;
2154 if (ret < 0)
2155 goto error;
2156 leaf = path->nodes[0];
2157 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2158 btrfs_release_path(path);
2159 continue;
2160 }
2161
2162 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2163 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2164 key.type != BTRFS_DEV_ITEM_KEY)
2165 break;
2166
2167 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2168 struct btrfs_dev_item);
2169 devid = btrfs_device_id(leaf, dev_item);
2170 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2171 BTRFS_UUID_SIZE);
2172 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2173 BTRFS_UUID_SIZE);
2174 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2175 fs_uuid);
2176 BUG_ON(!device); /* Logic error */
2177
2178 if (device->fs_devices->seeding) {
2179 btrfs_set_device_generation(leaf, dev_item,
2180 device->generation);
2181 btrfs_mark_buffer_dirty(leaf);
2182 }
2183
2184 path->slots[0]++;
2185 goto next_slot;
2186 }
2187 ret = 0;
2188 error:
2189 btrfs_free_path(path);
2190 return ret;
2191 }
2192
2193 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
2194 {
2195 struct request_queue *q;
2196 struct btrfs_trans_handle *trans;
2197 struct btrfs_device *device;
2198 struct block_device *bdev;
2199 struct list_head *devices;
2200 struct super_block *sb = root->fs_info->sb;
2201 struct rcu_string *name;
2202 u64 tmp;
2203 int seeding_dev = 0;
2204 int ret = 0;
2205
2206 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
2207 return -EROFS;
2208
2209 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2210 root->fs_info->bdev_holder);
2211 if (IS_ERR(bdev))
2212 return PTR_ERR(bdev);
2213
2214 if (root->fs_info->fs_devices->seeding) {
2215 seeding_dev = 1;
2216 down_write(&sb->s_umount);
2217 mutex_lock(&uuid_mutex);
2218 }
2219
2220 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2221
2222 devices = &root->fs_info->fs_devices->devices;
2223
2224 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2225 list_for_each_entry(device, devices, dev_list) {
2226 if (device->bdev == bdev) {
2227 ret = -EEXIST;
2228 mutex_unlock(
2229 &root->fs_info->fs_devices->device_list_mutex);
2230 goto error;
2231 }
2232 }
2233 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2234
2235 device = btrfs_alloc_device(root->fs_info, NULL, NULL);
2236 if (IS_ERR(device)) {
2237 /* we can safely leave the fs_devices entry around */
2238 ret = PTR_ERR(device);
2239 goto error;
2240 }
2241
2242 name = rcu_string_strdup(device_path, GFP_NOFS);
2243 if (!name) {
2244 kfree(device);
2245 ret = -ENOMEM;
2246 goto error;
2247 }
2248 rcu_assign_pointer(device->name, name);
2249
2250 trans = btrfs_start_transaction(root, 0);
2251 if (IS_ERR(trans)) {
2252 rcu_string_free(device->name);
2253 kfree(device);
2254 ret = PTR_ERR(trans);
2255 goto error;
2256 }
2257
2258 q = bdev_get_queue(bdev);
2259 if (blk_queue_discard(q))
2260 device->can_discard = 1;
2261 device->writeable = 1;
2262 device->generation = trans->transid;
2263 device->io_width = root->sectorsize;
2264 device->io_align = root->sectorsize;
2265 device->sector_size = root->sectorsize;
2266 device->total_bytes = i_size_read(bdev->bd_inode);
2267 device->disk_total_bytes = device->total_bytes;
2268 device->commit_total_bytes = device->total_bytes;
2269 device->dev_root = root->fs_info->dev_root;
2270 device->bdev = bdev;
2271 device->in_fs_metadata = 1;
2272 device->is_tgtdev_for_dev_replace = 0;
2273 device->mode = FMODE_EXCL;
2274 device->dev_stats_valid = 1;
2275 set_blocksize(device->bdev, 4096);
2276
2277 if (seeding_dev) {
2278 sb->s_flags &= ~MS_RDONLY;
2279 ret = btrfs_prepare_sprout(root);
2280 BUG_ON(ret); /* -ENOMEM */
2281 }
2282
2283 device->fs_devices = root->fs_info->fs_devices;
2284
2285 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2286 lock_chunks(root);
2287 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
2288 list_add(&device->dev_alloc_list,
2289 &root->fs_info->fs_devices->alloc_list);
2290 root->fs_info->fs_devices->num_devices++;
2291 root->fs_info->fs_devices->open_devices++;
2292 root->fs_info->fs_devices->rw_devices++;
2293 root->fs_info->fs_devices->total_devices++;
2294 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
2295
2296 spin_lock(&root->fs_info->free_chunk_lock);
2297 root->fs_info->free_chunk_space += device->total_bytes;
2298 spin_unlock(&root->fs_info->free_chunk_lock);
2299
2300 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
2301 root->fs_info->fs_devices->rotating = 1;
2302
2303 tmp = btrfs_super_total_bytes(root->fs_info->super_copy);
2304 btrfs_set_super_total_bytes(root->fs_info->super_copy,
2305 tmp + device->total_bytes);
2306
2307 tmp = btrfs_super_num_devices(root->fs_info->super_copy);
2308 btrfs_set_super_num_devices(root->fs_info->super_copy,
2309 tmp + 1);
2310
2311 /* add sysfs device entry */
2312 btrfs_kobj_add_device(root->fs_info->fs_devices, device);
2313
2314 /*
2315 * we've got more storage, clear any full flags on the space
2316 * infos
2317 */
2318 btrfs_clear_space_info_full(root->fs_info);
2319
2320 unlock_chunks(root);
2321 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2322
2323 if (seeding_dev) {
2324 lock_chunks(root);
2325 ret = init_first_rw_device(trans, root, device);
2326 unlock_chunks(root);
2327 if (ret) {
2328 btrfs_abort_transaction(trans, root, ret);
2329 goto error_trans;
2330 }
2331 }
2332
2333 ret = btrfs_add_device(trans, root, device);
2334 if (ret) {
2335 btrfs_abort_transaction(trans, root, ret);
2336 goto error_trans;
2337 }
2338
2339 if (seeding_dev) {
2340 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2341
2342 ret = btrfs_finish_sprout(trans, root);
2343 if (ret) {
2344 btrfs_abort_transaction(trans, root, ret);
2345 goto error_trans;
2346 }
2347
2348 /* Sprouting would change fsid of the mounted root,
2349 * so rename the fsid on the sysfs
2350 */
2351 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU",
2352 root->fs_info->fsid);
2353 if (kobject_rename(&root->fs_info->fs_devices->super_kobj,
2354 fsid_buf))
2355 pr_warn("BTRFS: sysfs: failed to create fsid for sprout\n");
2356 }
2357
2358 root->fs_info->num_tolerated_disk_barrier_failures =
2359 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2360 ret = btrfs_commit_transaction(trans, root);
2361
2362 if (seeding_dev) {
2363 mutex_unlock(&uuid_mutex);
2364 up_write(&sb->s_umount);
2365
2366 if (ret) /* transaction commit */
2367 return ret;
2368
2369 ret = btrfs_relocate_sys_chunks(root);
2370 if (ret < 0)
2371 btrfs_error(root->fs_info, ret,
2372 "Failed to relocate sys chunks after "
2373 "device initialization. This can be fixed "
2374 "using the \"btrfs balance\" command.");
2375 trans = btrfs_attach_transaction(root);
2376 if (IS_ERR(trans)) {
2377 if (PTR_ERR(trans) == -ENOENT)
2378 return 0;
2379 return PTR_ERR(trans);
2380 }
2381 ret = btrfs_commit_transaction(trans, root);
2382 }
2383
2384 /* Update ctime/mtime for libblkid */
2385 update_dev_time(device_path);
2386 return ret;
2387
2388 error_trans:
2389 btrfs_end_transaction(trans, root);
2390 rcu_string_free(device->name);
2391 btrfs_kobj_rm_device(root->fs_info->fs_devices, device);
2392 kfree(device);
2393 error:
2394 blkdev_put(bdev, FMODE_EXCL);
2395 if (seeding_dev) {
2396 mutex_unlock(&uuid_mutex);
2397 up_write(&sb->s_umount);
2398 }
2399 return ret;
2400 }
2401
2402 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2403 struct btrfs_device *srcdev,
2404 struct btrfs_device **device_out)
2405 {
2406 struct request_queue *q;
2407 struct btrfs_device *device;
2408 struct block_device *bdev;
2409 struct btrfs_fs_info *fs_info = root->fs_info;
2410 struct list_head *devices;
2411 struct rcu_string *name;
2412 u64 devid = BTRFS_DEV_REPLACE_DEVID;
2413 int ret = 0;
2414
2415 *device_out = NULL;
2416 if (fs_info->fs_devices->seeding) {
2417 btrfs_err(fs_info, "the filesystem is a seed filesystem!");
2418 return -EINVAL;
2419 }
2420
2421 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2422 fs_info->bdev_holder);
2423 if (IS_ERR(bdev)) {
2424 btrfs_err(fs_info, "target device %s is invalid!", device_path);
2425 return PTR_ERR(bdev);
2426 }
2427
2428 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2429
2430 devices = &fs_info->fs_devices->devices;
2431 list_for_each_entry(device, devices, dev_list) {
2432 if (device->bdev == bdev) {
2433 btrfs_err(fs_info, "target device is in the filesystem!");
2434 ret = -EEXIST;
2435 goto error;
2436 }
2437 }
2438
2439
2440 if (i_size_read(bdev->bd_inode) <
2441 btrfs_device_get_total_bytes(srcdev)) {
2442 btrfs_err(fs_info, "target device is smaller than source device!");
2443 ret = -EINVAL;
2444 goto error;
2445 }
2446
2447
2448 device = btrfs_alloc_device(NULL, &devid, NULL);
2449 if (IS_ERR(device)) {
2450 ret = PTR_ERR(device);
2451 goto error;
2452 }
2453
2454 name = rcu_string_strdup(device_path, GFP_NOFS);
2455 if (!name) {
2456 kfree(device);
2457 ret = -ENOMEM;
2458 goto error;
2459 }
2460 rcu_assign_pointer(device->name, name);
2461
2462 q = bdev_get_queue(bdev);
2463 if (blk_queue_discard(q))
2464 device->can_discard = 1;
2465 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2466 device->writeable = 1;
2467 device->generation = 0;
2468 device->io_width = root->sectorsize;
2469 device->io_align = root->sectorsize;
2470 device->sector_size = root->sectorsize;
2471 device->total_bytes = btrfs_device_get_total_bytes(srcdev);
2472 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev);
2473 device->bytes_used = btrfs_device_get_bytes_used(srcdev);
2474 ASSERT(list_empty(&srcdev->resized_list));
2475 device->commit_total_bytes = srcdev->commit_total_bytes;
2476 device->commit_bytes_used = device->bytes_used;
2477 device->dev_root = fs_info->dev_root;
2478 device->bdev = bdev;
2479 device->in_fs_metadata = 1;
2480 device->is_tgtdev_for_dev_replace = 1;
2481 device->mode = FMODE_EXCL;
2482 device->dev_stats_valid = 1;
2483 set_blocksize(device->bdev, 4096);
2484 device->fs_devices = fs_info->fs_devices;
2485 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2486 fs_info->fs_devices->num_devices++;
2487 fs_info->fs_devices->open_devices++;
2488 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2489
2490 *device_out = device;
2491 return ret;
2492
2493 error:
2494 blkdev_put(bdev, FMODE_EXCL);
2495 return ret;
2496 }
2497
2498 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2499 struct btrfs_device *tgtdev)
2500 {
2501 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2502 tgtdev->io_width = fs_info->dev_root->sectorsize;
2503 tgtdev->io_align = fs_info->dev_root->sectorsize;
2504 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2505 tgtdev->dev_root = fs_info->dev_root;
2506 tgtdev->in_fs_metadata = 1;
2507 }
2508
2509 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2510 struct btrfs_device *device)
2511 {
2512 int ret;
2513 struct btrfs_path *path;
2514 struct btrfs_root *root;
2515 struct btrfs_dev_item *dev_item;
2516 struct extent_buffer *leaf;
2517 struct btrfs_key key;
2518
2519 root = device->dev_root->fs_info->chunk_root;
2520
2521 path = btrfs_alloc_path();
2522 if (!path)
2523 return -ENOMEM;
2524
2525 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2526 key.type = BTRFS_DEV_ITEM_KEY;
2527 key.offset = device->devid;
2528
2529 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2530 if (ret < 0)
2531 goto out;
2532
2533 if (ret > 0) {
2534 ret = -ENOENT;
2535 goto out;
2536 }
2537
2538 leaf = path->nodes[0];
2539 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2540
2541 btrfs_set_device_id(leaf, dev_item, device->devid);
2542 btrfs_set_device_type(leaf, dev_item, device->type);
2543 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2544 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2545 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2546 btrfs_set_device_total_bytes(leaf, dev_item,
2547 btrfs_device_get_disk_total_bytes(device));
2548 btrfs_set_device_bytes_used(leaf, dev_item,
2549 btrfs_device_get_bytes_used(device));
2550 btrfs_mark_buffer_dirty(leaf);
2551
2552 out:
2553 btrfs_free_path(path);
2554 return ret;
2555 }
2556
2557 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2558 struct btrfs_device *device, u64 new_size)
2559 {
2560 struct btrfs_super_block *super_copy =
2561 device->dev_root->fs_info->super_copy;
2562 struct btrfs_fs_devices *fs_devices;
2563 u64 old_total;
2564 u64 diff;
2565
2566 if (!device->writeable)
2567 return -EACCES;
2568
2569 lock_chunks(device->dev_root);
2570 old_total = btrfs_super_total_bytes(super_copy);
2571 diff = new_size - device->total_bytes;
2572
2573 if (new_size <= device->total_bytes ||
2574 device->is_tgtdev_for_dev_replace) {
2575 unlock_chunks(device->dev_root);
2576 return -EINVAL;
2577 }
2578
2579 fs_devices = device->dev_root->fs_info->fs_devices;
2580
2581 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2582 device->fs_devices->total_rw_bytes += diff;
2583
2584 btrfs_device_set_total_bytes(device, new_size);
2585 btrfs_device_set_disk_total_bytes(device, new_size);
2586 btrfs_clear_space_info_full(device->dev_root->fs_info);
2587 if (list_empty(&device->resized_list))
2588 list_add_tail(&device->resized_list,
2589 &fs_devices->resized_devices);
2590 unlock_chunks(device->dev_root);
2591
2592 return btrfs_update_device(trans, device);
2593 }
2594
2595 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2596 struct btrfs_root *root, u64 chunk_objectid,
2597 u64 chunk_offset)
2598 {
2599 int ret;
2600 struct btrfs_path *path;
2601 struct btrfs_key key;
2602
2603 root = root->fs_info->chunk_root;
2604 path = btrfs_alloc_path();
2605 if (!path)
2606 return -ENOMEM;
2607
2608 key.objectid = chunk_objectid;
2609 key.offset = chunk_offset;
2610 key.type = BTRFS_CHUNK_ITEM_KEY;
2611
2612 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2613 if (ret < 0)
2614 goto out;
2615 else if (ret > 0) { /* Logic error or corruption */
2616 btrfs_error(root->fs_info, -ENOENT,
2617 "Failed lookup while freeing chunk.");
2618 ret = -ENOENT;
2619 goto out;
2620 }
2621
2622 ret = btrfs_del_item(trans, root, path);
2623 if (ret < 0)
2624 btrfs_error(root->fs_info, ret,
2625 "Failed to delete chunk item.");
2626 out:
2627 btrfs_free_path(path);
2628 return ret;
2629 }
2630
2631 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2632 chunk_offset)
2633 {
2634 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2635 struct btrfs_disk_key *disk_key;
2636 struct btrfs_chunk *chunk;
2637 u8 *ptr;
2638 int ret = 0;
2639 u32 num_stripes;
2640 u32 array_size;
2641 u32 len = 0;
2642 u32 cur;
2643 struct btrfs_key key;
2644
2645 lock_chunks(root);
2646 array_size = btrfs_super_sys_array_size(super_copy);
2647
2648 ptr = super_copy->sys_chunk_array;
2649 cur = 0;
2650
2651 while (cur < array_size) {
2652 disk_key = (struct btrfs_disk_key *)ptr;
2653 btrfs_disk_key_to_cpu(&key, disk_key);
2654
2655 len = sizeof(*disk_key);
2656
2657 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2658 chunk = (struct btrfs_chunk *)(ptr + len);
2659 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2660 len += btrfs_chunk_item_size(num_stripes);
2661 } else {
2662 ret = -EIO;
2663 break;
2664 }
2665 if (key.objectid == chunk_objectid &&
2666 key.offset == chunk_offset) {
2667 memmove(ptr, ptr + len, array_size - (cur + len));
2668 array_size -= len;
2669 btrfs_set_super_sys_array_size(super_copy, array_size);
2670 } else {
2671 ptr += len;
2672 cur += len;
2673 }
2674 }
2675 unlock_chunks(root);
2676 return ret;
2677 }
2678
2679 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
2680 struct btrfs_root *root, u64 chunk_offset)
2681 {
2682 struct extent_map_tree *em_tree;
2683 struct extent_map *em;
2684 struct btrfs_root *extent_root = root->fs_info->extent_root;
2685 struct map_lookup *map;
2686 u64 dev_extent_len = 0;
2687 u64 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2688 int i, ret = 0;
2689
2690 /* Just in case */
2691 root = root->fs_info->chunk_root;
2692 em_tree = &root->fs_info->mapping_tree.map_tree;
2693
2694 read_lock(&em_tree->lock);
2695 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2696 read_unlock(&em_tree->lock);
2697
2698 if (!em || em->start > chunk_offset ||
2699 em->start + em->len < chunk_offset) {
2700 /*
2701 * This is a logic error, but we don't want to just rely on the
2702 * user having built with ASSERT enabled, so if ASSERT doens't
2703 * do anything we still error out.
2704 */
2705 ASSERT(0);
2706 if (em)
2707 free_extent_map(em);
2708 return -EINVAL;
2709 }
2710 map = (struct map_lookup *)em->bdev;
2711 lock_chunks(root->fs_info->chunk_root);
2712 check_system_chunk(trans, extent_root, map->type);
2713 unlock_chunks(root->fs_info->chunk_root);
2714
2715 for (i = 0; i < map->num_stripes; i++) {
2716 struct btrfs_device *device = map->stripes[i].dev;
2717 ret = btrfs_free_dev_extent(trans, device,
2718 map->stripes[i].physical,
2719 &dev_extent_len);
2720 if (ret) {
2721 btrfs_abort_transaction(trans, root, ret);
2722 goto out;
2723 }
2724
2725 if (device->bytes_used > 0) {
2726 lock_chunks(root);
2727 btrfs_device_set_bytes_used(device,
2728 device->bytes_used - dev_extent_len);
2729 spin_lock(&root->fs_info->free_chunk_lock);
2730 root->fs_info->free_chunk_space += dev_extent_len;
2731 spin_unlock(&root->fs_info->free_chunk_lock);
2732 btrfs_clear_space_info_full(root->fs_info);
2733 unlock_chunks(root);
2734 }
2735
2736 if (map->stripes[i].dev) {
2737 ret = btrfs_update_device(trans, map->stripes[i].dev);
2738 if (ret) {
2739 btrfs_abort_transaction(trans, root, ret);
2740 goto out;
2741 }
2742 }
2743 }
2744 ret = btrfs_free_chunk(trans, root, chunk_objectid, chunk_offset);
2745 if (ret) {
2746 btrfs_abort_transaction(trans, root, ret);
2747 goto out;
2748 }
2749
2750 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2751
2752 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2753 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2754 if (ret) {
2755 btrfs_abort_transaction(trans, root, ret);
2756 goto out;
2757 }
2758 }
2759
2760 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset, em);
2761 if (ret) {
2762 btrfs_abort_transaction(trans, extent_root, ret);
2763 goto out;
2764 }
2765
2766 out:
2767 /* once for us */
2768 free_extent_map(em);
2769 return ret;
2770 }
2771
2772 static int btrfs_relocate_chunk(struct btrfs_root *root, u64 chunk_offset)
2773 {
2774 struct btrfs_root *extent_root;
2775 struct btrfs_trans_handle *trans;
2776 int ret;
2777
2778 root = root->fs_info->chunk_root;
2779 extent_root = root->fs_info->extent_root;
2780
2781 /*
2782 * Prevent races with automatic removal of unused block groups.
2783 * After we relocate and before we remove the chunk with offset
2784 * chunk_offset, automatic removal of the block group can kick in,
2785 * resulting in a failure when calling btrfs_remove_chunk() below.
2786 *
2787 * Make sure to acquire this mutex before doing a tree search (dev
2788 * or chunk trees) to find chunks. Otherwise the cleaner kthread might
2789 * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after
2790 * we release the path used to search the chunk/dev tree and before
2791 * the current task acquires this mutex and calls us.
2792 */
2793 ASSERT(mutex_is_locked(&root->fs_info->delete_unused_bgs_mutex));
2794
2795 ret = btrfs_can_relocate(extent_root, chunk_offset);
2796 if (ret)
2797 return -ENOSPC;
2798
2799 /* step one, relocate all the extents inside this chunk */
2800 btrfs_scrub_pause(root);
2801 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2802 btrfs_scrub_continue(root);
2803 if (ret)
2804 return ret;
2805
2806 trans = btrfs_start_transaction(root, 0);
2807 if (IS_ERR(trans)) {
2808 ret = PTR_ERR(trans);
2809 btrfs_std_error(root->fs_info, ret);
2810 return ret;
2811 }
2812
2813 /*
2814 * step two, delete the device extents and the
2815 * chunk tree entries
2816 */
2817 ret = btrfs_remove_chunk(trans, root, chunk_offset);
2818 btrfs_end_transaction(trans, root);
2819 return ret;
2820 }
2821
2822 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2823 {
2824 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2825 struct btrfs_path *path;
2826 struct extent_buffer *leaf;
2827 struct btrfs_chunk *chunk;
2828 struct btrfs_key key;
2829 struct btrfs_key found_key;
2830 u64 chunk_type;
2831 bool retried = false;
2832 int failed = 0;
2833 int ret;
2834
2835 path = btrfs_alloc_path();
2836 if (!path)
2837 return -ENOMEM;
2838
2839 again:
2840 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2841 key.offset = (u64)-1;
2842 key.type = BTRFS_CHUNK_ITEM_KEY;
2843
2844 while (1) {
2845 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
2846 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2847 if (ret < 0) {
2848 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2849 goto error;
2850 }
2851 BUG_ON(ret == 0); /* Corruption */
2852
2853 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2854 key.type);
2855 if (ret)
2856 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2857 if (ret < 0)
2858 goto error;
2859 if (ret > 0)
2860 break;
2861
2862 leaf = path->nodes[0];
2863 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2864
2865 chunk = btrfs_item_ptr(leaf, path->slots[0],
2866 struct btrfs_chunk);
2867 chunk_type = btrfs_chunk_type(leaf, chunk);
2868 btrfs_release_path(path);
2869
2870 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2871 ret = btrfs_relocate_chunk(chunk_root,
2872 found_key.offset);
2873 if (ret == -ENOSPC)
2874 failed++;
2875 else
2876 BUG_ON(ret);
2877 }
2878 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2879
2880 if (found_key.offset == 0)
2881 break;
2882 key.offset = found_key.offset - 1;
2883 }
2884 ret = 0;
2885 if (failed && !retried) {
2886 failed = 0;
2887 retried = true;
2888 goto again;
2889 } else if (WARN_ON(failed && retried)) {
2890 ret = -ENOSPC;
2891 }
2892 error:
2893 btrfs_free_path(path);
2894 return ret;
2895 }
2896
2897 static int insert_balance_item(struct btrfs_root *root,
2898 struct btrfs_balance_control *bctl)
2899 {
2900 struct btrfs_trans_handle *trans;
2901 struct btrfs_balance_item *item;
2902 struct btrfs_disk_balance_args disk_bargs;
2903 struct btrfs_path *path;
2904 struct extent_buffer *leaf;
2905 struct btrfs_key key;
2906 int ret, err;
2907
2908 path = btrfs_alloc_path();
2909 if (!path)
2910 return -ENOMEM;
2911
2912 trans = btrfs_start_transaction(root, 0);
2913 if (IS_ERR(trans)) {
2914 btrfs_free_path(path);
2915 return PTR_ERR(trans);
2916 }
2917
2918 key.objectid = BTRFS_BALANCE_OBJECTID;
2919 key.type = BTRFS_BALANCE_ITEM_KEY;
2920 key.offset = 0;
2921
2922 ret = btrfs_insert_empty_item(trans, root, path, &key,
2923 sizeof(*item));
2924 if (ret)
2925 goto out;
2926
2927 leaf = path->nodes[0];
2928 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2929
2930 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2931
2932 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2933 btrfs_set_balance_data(leaf, item, &disk_bargs);
2934 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2935 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2936 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2937 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2938
2939 btrfs_set_balance_flags(leaf, item, bctl->flags);
2940
2941 btrfs_mark_buffer_dirty(leaf);
2942 out:
2943 btrfs_free_path(path);
2944 err = btrfs_commit_transaction(trans, root);
2945 if (err && !ret)
2946 ret = err;
2947 return ret;
2948 }
2949
2950 static int del_balance_item(struct btrfs_root *root)
2951 {
2952 struct btrfs_trans_handle *trans;
2953 struct btrfs_path *path;
2954 struct btrfs_key key;
2955 int ret, err;
2956
2957 path = btrfs_alloc_path();
2958 if (!path)
2959 return -ENOMEM;
2960
2961 trans = btrfs_start_transaction(root, 0);
2962 if (IS_ERR(trans)) {
2963 btrfs_free_path(path);
2964 return PTR_ERR(trans);
2965 }
2966
2967 key.objectid = BTRFS_BALANCE_OBJECTID;
2968 key.type = BTRFS_BALANCE_ITEM_KEY;
2969 key.offset = 0;
2970
2971 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2972 if (ret < 0)
2973 goto out;
2974 if (ret > 0) {
2975 ret = -ENOENT;
2976 goto out;
2977 }
2978
2979 ret = btrfs_del_item(trans, root, path);
2980 out:
2981 btrfs_free_path(path);
2982 err = btrfs_commit_transaction(trans, root);
2983 if (err && !ret)
2984 ret = err;
2985 return ret;
2986 }
2987
2988 /*
2989 * This is a heuristic used to reduce the number of chunks balanced on
2990 * resume after balance was interrupted.
2991 */
2992 static void update_balance_args(struct btrfs_balance_control *bctl)
2993 {
2994 /*
2995 * Turn on soft mode for chunk types that were being converted.
2996 */
2997 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
2998 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
2999 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
3000 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
3001 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
3002 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
3003
3004 /*
3005 * Turn on usage filter if is not already used. The idea is
3006 * that chunks that we have already balanced should be
3007 * reasonably full. Don't do it for chunks that are being
3008 * converted - that will keep us from relocating unconverted
3009 * (albeit full) chunks.
3010 */
3011 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3012 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3013 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
3014 bctl->data.usage = 90;
3015 }
3016 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3017 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3018 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
3019 bctl->sys.usage = 90;
3020 }
3021 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3022 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3023 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
3024 bctl->meta.usage = 90;
3025 }
3026 }
3027
3028 /*
3029 * Should be called with both balance and volume mutexes held to
3030 * serialize other volume operations (add_dev/rm_dev/resize) with
3031 * restriper. Same goes for unset_balance_control.
3032 */
3033 static void set_balance_control(struct btrfs_balance_control *bctl)
3034 {
3035 struct btrfs_fs_info *fs_info = bctl->fs_info;
3036
3037 BUG_ON(fs_info->balance_ctl);
3038
3039 spin_lock(&fs_info->balance_lock);
3040 fs_info->balance_ctl = bctl;
3041 spin_unlock(&fs_info->balance_lock);
3042 }
3043
3044 static void unset_balance_control(struct btrfs_fs_info *fs_info)
3045 {
3046 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3047
3048 BUG_ON(!fs_info->balance_ctl);
3049
3050 spin_lock(&fs_info->balance_lock);
3051 fs_info->balance_ctl = NULL;
3052 spin_unlock(&fs_info->balance_lock);
3053
3054 kfree(bctl);
3055 }
3056
3057 /*
3058 * Balance filters. Return 1 if chunk should be filtered out
3059 * (should not be balanced).
3060 */
3061 static int chunk_profiles_filter(u64 chunk_type,
3062 struct btrfs_balance_args *bargs)
3063 {
3064 chunk_type = chunk_to_extended(chunk_type) &
3065 BTRFS_EXTENDED_PROFILE_MASK;
3066
3067 if (bargs->profiles & chunk_type)
3068 return 0;
3069
3070 return 1;
3071 }
3072
3073 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
3074 struct btrfs_balance_args *bargs)
3075 {
3076 struct btrfs_block_group_cache *cache;
3077 u64 chunk_used, user_thresh;
3078 int ret = 1;
3079
3080 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3081 chunk_used = btrfs_block_group_used(&cache->item);
3082
3083 if (bargs->usage == 0)
3084 user_thresh = 1;
3085 else if (bargs->usage > 100)
3086 user_thresh = cache->key.offset;
3087 else
3088 user_thresh = div_factor_fine(cache->key.offset,
3089 bargs->usage);
3090
3091 if (chunk_used < user_thresh)
3092 ret = 0;
3093
3094 btrfs_put_block_group(cache);
3095 return ret;
3096 }
3097
3098 static int chunk_devid_filter(struct extent_buffer *leaf,
3099 struct btrfs_chunk *chunk,
3100 struct btrfs_balance_args *bargs)
3101 {
3102 struct btrfs_stripe *stripe;
3103 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3104 int i;
3105
3106 for (i = 0; i < num_stripes; i++) {
3107 stripe = btrfs_stripe_nr(chunk, i);
3108 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
3109 return 0;
3110 }
3111
3112 return 1;
3113 }
3114
3115 /* [pstart, pend) */
3116 static int chunk_drange_filter(struct extent_buffer *leaf,
3117 struct btrfs_chunk *chunk,
3118 u64 chunk_offset,
3119 struct btrfs_balance_args *bargs)
3120 {
3121 struct btrfs_stripe *stripe;
3122 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3123 u64 stripe_offset;
3124 u64 stripe_length;
3125 int factor;
3126 int i;
3127
3128 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3129 return 0;
3130
3131 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
3132 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
3133 factor = num_stripes / 2;
3134 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
3135 factor = num_stripes - 1;
3136 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
3137 factor = num_stripes - 2;
3138 } else {
3139 factor = num_stripes;
3140 }
3141
3142 for (i = 0; i < num_stripes; i++) {
3143 stripe = btrfs_stripe_nr(chunk, i);
3144 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3145 continue;
3146
3147 stripe_offset = btrfs_stripe_offset(leaf, stripe);
3148 stripe_length = btrfs_chunk_length(leaf, chunk);
3149 stripe_length = div_u64(stripe_length, factor);
3150
3151 if (stripe_offset < bargs->pend &&
3152 stripe_offset + stripe_length > bargs->pstart)
3153 return 0;
3154 }
3155
3156 return 1;
3157 }
3158
3159 /* [vstart, vend) */
3160 static int chunk_vrange_filter(struct extent_buffer *leaf,
3161 struct btrfs_chunk *chunk,
3162 u64 chunk_offset,
3163 struct btrfs_balance_args *bargs)
3164 {
3165 if (chunk_offset < bargs->vend &&
3166 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
3167 /* at least part of the chunk is inside this vrange */
3168 return 0;
3169
3170 return 1;
3171 }
3172
3173 static int chunk_soft_convert_filter(u64 chunk_type,
3174 struct btrfs_balance_args *bargs)
3175 {
3176 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
3177 return 0;
3178
3179 chunk_type = chunk_to_extended(chunk_type) &
3180 BTRFS_EXTENDED_PROFILE_MASK;
3181
3182 if (bargs->target == chunk_type)
3183 return 1;
3184
3185 return 0;
3186 }
3187
3188 static int should_balance_chunk(struct btrfs_root *root,
3189 struct extent_buffer *leaf,
3190 struct btrfs_chunk *chunk, u64 chunk_offset)
3191 {
3192 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
3193 struct btrfs_balance_args *bargs = NULL;
3194 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
3195
3196 /* type filter */
3197 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
3198 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
3199 return 0;
3200 }
3201
3202 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3203 bargs = &bctl->data;
3204 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3205 bargs = &bctl->sys;
3206 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3207 bargs = &bctl->meta;
3208
3209 /* profiles filter */
3210 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
3211 chunk_profiles_filter(chunk_type, bargs)) {
3212 return 0;
3213 }
3214
3215 /* usage filter */
3216 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
3217 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
3218 return 0;
3219 }
3220
3221 /* devid filter */
3222 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
3223 chunk_devid_filter(leaf, chunk, bargs)) {
3224 return 0;
3225 }
3226
3227 /* drange filter, makes sense only with devid filter */
3228 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
3229 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
3230 return 0;
3231 }
3232
3233 /* vrange filter */
3234 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
3235 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
3236 return 0;
3237 }
3238
3239 /* soft profile changing mode */
3240 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
3241 chunk_soft_convert_filter(chunk_type, bargs)) {
3242 return 0;
3243 }
3244
3245 /*
3246 * limited by count, must be the last filter
3247 */
3248 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
3249 if (bargs->limit == 0)
3250 return 0;
3251 else
3252 bargs->limit--;
3253 }
3254
3255 return 1;
3256 }
3257
3258 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
3259 {
3260 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3261 struct btrfs_root *chunk_root = fs_info->chunk_root;
3262 struct btrfs_root *dev_root = fs_info->dev_root;
3263 struct list_head *devices;
3264 struct btrfs_device *device;
3265 u64 old_size;
3266 u64 size_to_free;
3267 struct btrfs_chunk *chunk;
3268 struct btrfs_path *path;
3269 struct btrfs_key key;
3270 struct btrfs_key found_key;
3271 struct btrfs_trans_handle *trans;
3272 struct extent_buffer *leaf;
3273 int slot;
3274 int ret;
3275 int enospc_errors = 0;
3276 bool counting = true;
3277 u64 limit_data = bctl->data.limit;
3278 u64 limit_meta = bctl->meta.limit;
3279 u64 limit_sys = bctl->sys.limit;
3280
3281 /* step one make some room on all the devices */
3282 devices = &fs_info->fs_devices->devices;
3283 list_for_each_entry(device, devices, dev_list) {
3284 old_size = btrfs_device_get_total_bytes(device);
3285 size_to_free = div_factor(old_size, 1);
3286 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
3287 if (!device->writeable ||
3288 btrfs_device_get_total_bytes(device) -
3289 btrfs_device_get_bytes_used(device) > size_to_free ||
3290 device->is_tgtdev_for_dev_replace)
3291 continue;
3292
3293 ret = btrfs_shrink_device(device, old_size - size_to_free);
3294 if (ret == -ENOSPC)
3295 break;
3296 BUG_ON(ret);
3297
3298 trans = btrfs_start_transaction(dev_root, 0);
3299 BUG_ON(IS_ERR(trans));
3300
3301 ret = btrfs_grow_device(trans, device, old_size);
3302 BUG_ON(ret);
3303
3304 btrfs_end_transaction(trans, dev_root);
3305 }
3306
3307 /* step two, relocate all the chunks */
3308 path = btrfs_alloc_path();
3309 if (!path) {
3310 ret = -ENOMEM;
3311 goto error;
3312 }
3313
3314 /* zero out stat counters */
3315 spin_lock(&fs_info->balance_lock);
3316 memset(&bctl->stat, 0, sizeof(bctl->stat));
3317 spin_unlock(&fs_info->balance_lock);
3318 again:
3319 if (!counting) {
3320 bctl->data.limit = limit_data;
3321 bctl->meta.limit = limit_meta;
3322 bctl->sys.limit = limit_sys;
3323 }
3324 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3325 key.offset = (u64)-1;
3326 key.type = BTRFS_CHUNK_ITEM_KEY;
3327
3328 while (1) {
3329 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
3330 atomic_read(&fs_info->balance_cancel_req)) {
3331 ret = -ECANCELED;
3332 goto error;
3333 }
3334
3335 mutex_lock(&fs_info->delete_unused_bgs_mutex);
3336 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3337 if (ret < 0) {
3338 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3339 goto error;
3340 }
3341
3342 /*
3343 * this shouldn't happen, it means the last relocate
3344 * failed
3345 */
3346 if (ret == 0)
3347 BUG(); /* FIXME break ? */
3348
3349 ret = btrfs_previous_item(chunk_root, path, 0,
3350 BTRFS_CHUNK_ITEM_KEY);
3351 if (ret) {
3352 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3353 ret = 0;
3354 break;
3355 }
3356
3357 leaf = path->nodes[0];
3358 slot = path->slots[0];
3359 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3360
3361 if (found_key.objectid != key.objectid) {
3362 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3363 break;
3364 }
3365
3366 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3367
3368 if (!counting) {
3369 spin_lock(&fs_info->balance_lock);
3370 bctl->stat.considered++;
3371 spin_unlock(&fs_info->balance_lock);
3372 }
3373
3374 ret = should_balance_chunk(chunk_root, leaf, chunk,
3375 found_key.offset);
3376 btrfs_release_path(path);
3377 if (!ret) {
3378 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3379 goto loop;
3380 }
3381
3382 if (counting) {
3383 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3384 spin_lock(&fs_info->balance_lock);
3385 bctl->stat.expected++;
3386 spin_unlock(&fs_info->balance_lock);
3387 goto loop;
3388 }
3389
3390 ret = btrfs_relocate_chunk(chunk_root,
3391 found_key.offset);
3392 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3393 if (ret && ret != -ENOSPC)
3394 goto error;
3395 if (ret == -ENOSPC) {
3396 enospc_errors++;
3397 } else {
3398 spin_lock(&fs_info->balance_lock);
3399 bctl->stat.completed++;
3400 spin_unlock(&fs_info->balance_lock);
3401 }
3402 loop:
3403 if (found_key.offset == 0)
3404 break;
3405 key.offset = found_key.offset - 1;
3406 }
3407
3408 if (counting) {
3409 btrfs_release_path(path);
3410 counting = false;
3411 goto again;
3412 }
3413 error:
3414 btrfs_free_path(path);
3415 if (enospc_errors) {
3416 btrfs_info(fs_info, "%d enospc errors during balance",
3417 enospc_errors);
3418 if (!ret)
3419 ret = -ENOSPC;
3420 }
3421
3422 return ret;
3423 }
3424
3425 /**
3426 * alloc_profile_is_valid - see if a given profile is valid and reduced
3427 * @flags: profile to validate
3428 * @extended: if true @flags is treated as an extended profile
3429 */
3430 static int alloc_profile_is_valid(u64 flags, int extended)
3431 {
3432 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
3433 BTRFS_BLOCK_GROUP_PROFILE_MASK);
3434
3435 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
3436
3437 /* 1) check that all other bits are zeroed */
3438 if (flags & ~mask)
3439 return 0;
3440
3441 /* 2) see if profile is reduced */
3442 if (flags == 0)
3443 return !extended; /* "0" is valid for usual profiles */
3444
3445 /* true if exactly one bit set */
3446 return (flags & (flags - 1)) == 0;
3447 }
3448
3449 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
3450 {
3451 /* cancel requested || normal exit path */
3452 return atomic_read(&fs_info->balance_cancel_req) ||
3453 (atomic_read(&fs_info->balance_pause_req) == 0 &&
3454 atomic_read(&fs_info->balance_cancel_req) == 0);
3455 }
3456
3457 static void __cancel_balance(struct btrfs_fs_info *fs_info)
3458 {
3459 int ret;
3460
3461 unset_balance_control(fs_info);
3462 ret = del_balance_item(fs_info->tree_root);
3463 if (ret)
3464 btrfs_std_error(fs_info, ret);
3465
3466 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3467 }
3468
3469 /*
3470 * Should be called with both balance and volume mutexes held
3471 */
3472 int btrfs_balance(struct btrfs_balance_control *bctl,
3473 struct btrfs_ioctl_balance_args *bargs)
3474 {
3475 struct btrfs_fs_info *fs_info = bctl->fs_info;
3476 u64 allowed;
3477 int mixed = 0;
3478 int ret;
3479 u64 num_devices;
3480 unsigned seq;
3481
3482 if (btrfs_fs_closing(fs_info) ||
3483 atomic_read(&fs_info->balance_pause_req) ||
3484 atomic_read(&fs_info->balance_cancel_req)) {
3485 ret = -EINVAL;
3486 goto out;
3487 }
3488
3489 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3490 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3491 mixed = 1;
3492
3493 /*
3494 * In case of mixed groups both data and meta should be picked,
3495 * and identical options should be given for both of them.
3496 */
3497 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3498 if (mixed && (bctl->flags & allowed)) {
3499 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3500 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3501 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3502 btrfs_err(fs_info, "with mixed groups data and "
3503 "metadata balance options must be the same");
3504 ret = -EINVAL;
3505 goto out;
3506 }
3507 }
3508
3509 num_devices = fs_info->fs_devices->num_devices;
3510 btrfs_dev_replace_lock(&fs_info->dev_replace);
3511 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3512 BUG_ON(num_devices < 1);
3513 num_devices--;
3514 }
3515 btrfs_dev_replace_unlock(&fs_info->dev_replace);
3516 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3517 if (num_devices == 1)
3518 allowed |= BTRFS_BLOCK_GROUP_DUP;
3519 else if (num_devices > 1)
3520 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3521 if (num_devices > 2)
3522 allowed |= BTRFS_BLOCK_GROUP_RAID5;
3523 if (num_devices > 3)
3524 allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
3525 BTRFS_BLOCK_GROUP_RAID6);
3526 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3527 (!alloc_profile_is_valid(bctl->data.target, 1) ||
3528 (bctl->data.target & ~allowed))) {
3529 btrfs_err(fs_info, "unable to start balance with target "
3530 "data profile %llu",
3531 bctl->data.target);
3532 ret = -EINVAL;
3533 goto out;
3534 }
3535 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3536 (!alloc_profile_is_valid(bctl->meta.target, 1) ||
3537 (bctl->meta.target & ~allowed))) {
3538 btrfs_err(fs_info,
3539 "unable to start balance with target metadata profile %llu",
3540 bctl->meta.target);
3541 ret = -EINVAL;
3542 goto out;
3543 }
3544 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3545 (!alloc_profile_is_valid(bctl->sys.target, 1) ||
3546 (bctl->sys.target & ~allowed))) {
3547 btrfs_err(fs_info,
3548 "unable to start balance with target system profile %llu",
3549 bctl->sys.target);
3550 ret = -EINVAL;
3551 goto out;
3552 }
3553
3554 /* allow dup'ed data chunks only in mixed mode */
3555 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3556 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
3557 btrfs_err(fs_info, "dup for data is not allowed");
3558 ret = -EINVAL;
3559 goto out;
3560 }
3561
3562 /* allow to reduce meta or sys integrity only if force set */
3563 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3564 BTRFS_BLOCK_GROUP_RAID10 |
3565 BTRFS_BLOCK_GROUP_RAID5 |
3566 BTRFS_BLOCK_GROUP_RAID6;
3567 do {
3568 seq = read_seqbegin(&fs_info->profiles_lock);
3569
3570 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3571 (fs_info->avail_system_alloc_bits & allowed) &&
3572 !(bctl->sys.target & allowed)) ||
3573 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3574 (fs_info->avail_metadata_alloc_bits & allowed) &&
3575 !(bctl->meta.target & allowed))) {
3576 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3577 btrfs_info(fs_info, "force reducing metadata integrity");
3578 } else {
3579 btrfs_err(fs_info, "balance will reduce metadata "
3580 "integrity, use force if you want this");
3581 ret = -EINVAL;
3582 goto out;
3583 }
3584 }
3585 } while (read_seqretry(&fs_info->profiles_lock, seq));
3586
3587 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3588 int num_tolerated_disk_barrier_failures;
3589 u64 target = bctl->sys.target;
3590
3591 num_tolerated_disk_barrier_failures =
3592 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3593 if (num_tolerated_disk_barrier_failures > 0 &&
3594 (target &
3595 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 |
3596 BTRFS_AVAIL_ALLOC_BIT_SINGLE)))
3597 num_tolerated_disk_barrier_failures = 0;
3598 else if (num_tolerated_disk_barrier_failures > 1 &&
3599 (target &
3600 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)))
3601 num_tolerated_disk_barrier_failures = 1;
3602
3603 fs_info->num_tolerated_disk_barrier_failures =
3604 num_tolerated_disk_barrier_failures;
3605 }
3606
3607 ret = insert_balance_item(fs_info->tree_root, bctl);
3608 if (ret && ret != -EEXIST)
3609 goto out;
3610
3611 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3612 BUG_ON(ret == -EEXIST);
3613 set_balance_control(bctl);
3614 } else {
3615 BUG_ON(ret != -EEXIST);
3616 spin_lock(&fs_info->balance_lock);
3617 update_balance_args(bctl);
3618 spin_unlock(&fs_info->balance_lock);
3619 }
3620
3621 atomic_inc(&fs_info->balance_running);
3622 mutex_unlock(&fs_info->balance_mutex);
3623
3624 ret = __btrfs_balance(fs_info);
3625
3626 mutex_lock(&fs_info->balance_mutex);
3627 atomic_dec(&fs_info->balance_running);
3628
3629 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3630 fs_info->num_tolerated_disk_barrier_failures =
3631 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3632 }
3633
3634 if (bargs) {
3635 memset(bargs, 0, sizeof(*bargs));
3636 update_ioctl_balance_args(fs_info, 0, bargs);
3637 }
3638
3639 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3640 balance_need_close(fs_info)) {
3641 __cancel_balance(fs_info);
3642 }
3643
3644 wake_up(&fs_info->balance_wait_q);
3645
3646 return ret;
3647 out:
3648 if (bctl->flags & BTRFS_BALANCE_RESUME)
3649 __cancel_balance(fs_info);
3650 else {
3651 kfree(bctl);
3652 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3653 }
3654 return ret;
3655 }
3656
3657 static int balance_kthread(void *data)
3658 {
3659 struct btrfs_fs_info *fs_info = data;
3660 int ret = 0;
3661
3662 mutex_lock(&fs_info->volume_mutex);
3663 mutex_lock(&fs_info->balance_mutex);
3664
3665 if (fs_info->balance_ctl) {
3666 btrfs_info(fs_info, "continuing balance");
3667 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3668 }
3669
3670 mutex_unlock(&fs_info->balance_mutex);
3671 mutex_unlock(&fs_info->volume_mutex);
3672
3673 return ret;
3674 }
3675
3676 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3677 {
3678 struct task_struct *tsk;
3679
3680 spin_lock(&fs_info->balance_lock);
3681 if (!fs_info->balance_ctl) {
3682 spin_unlock(&fs_info->balance_lock);
3683 return 0;
3684 }
3685 spin_unlock(&fs_info->balance_lock);
3686
3687 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3688 btrfs_info(fs_info, "force skipping balance");
3689 return 0;
3690 }
3691
3692 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3693 return PTR_ERR_OR_ZERO(tsk);
3694 }
3695
3696 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3697 {
3698 struct btrfs_balance_control *bctl;
3699 struct btrfs_balance_item *item;
3700 struct btrfs_disk_balance_args disk_bargs;
3701 struct btrfs_path *path;
3702 struct extent_buffer *leaf;
3703 struct btrfs_key key;
3704 int ret;
3705
3706 path = btrfs_alloc_path();
3707 if (!path)
3708 return -ENOMEM;
3709
3710 key.objectid = BTRFS_BALANCE_OBJECTID;
3711 key.type = BTRFS_BALANCE_ITEM_KEY;
3712 key.offset = 0;
3713
3714 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3715 if (ret < 0)
3716 goto out;
3717 if (ret > 0) { /* ret = -ENOENT; */
3718 ret = 0;
3719 goto out;
3720 }
3721
3722 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3723 if (!bctl) {
3724 ret = -ENOMEM;
3725 goto out;
3726 }
3727
3728 leaf = path->nodes[0];
3729 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3730
3731 bctl->fs_info = fs_info;
3732 bctl->flags = btrfs_balance_flags(leaf, item);
3733 bctl->flags |= BTRFS_BALANCE_RESUME;
3734
3735 btrfs_balance_data(leaf, item, &disk_bargs);
3736 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3737 btrfs_balance_meta(leaf, item, &disk_bargs);
3738 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3739 btrfs_balance_sys(leaf, item, &disk_bargs);
3740 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3741
3742 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3743
3744 mutex_lock(&fs_info->volume_mutex);
3745 mutex_lock(&fs_info->balance_mutex);
3746
3747 set_balance_control(bctl);
3748
3749 mutex_unlock(&fs_info->balance_mutex);
3750 mutex_unlock(&fs_info->volume_mutex);
3751 out:
3752 btrfs_free_path(path);
3753 return ret;
3754 }
3755
3756 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3757 {
3758 int ret = 0;
3759
3760 mutex_lock(&fs_info->balance_mutex);
3761 if (!fs_info->balance_ctl) {
3762 mutex_unlock(&fs_info->balance_mutex);
3763 return -ENOTCONN;
3764 }
3765
3766 if (atomic_read(&fs_info->balance_running)) {
3767 atomic_inc(&fs_info->balance_pause_req);
3768 mutex_unlock(&fs_info->balance_mutex);
3769
3770 wait_event(fs_info->balance_wait_q,
3771 atomic_read(&fs_info->balance_running) == 0);
3772
3773 mutex_lock(&fs_info->balance_mutex);
3774 /* we are good with balance_ctl ripped off from under us */
3775 BUG_ON(atomic_read(&fs_info->balance_running));
3776 atomic_dec(&fs_info->balance_pause_req);
3777 } else {
3778 ret = -ENOTCONN;
3779 }
3780
3781 mutex_unlock(&fs_info->balance_mutex);
3782 return ret;
3783 }
3784
3785 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3786 {
3787 if (fs_info->sb->s_flags & MS_RDONLY)
3788 return -EROFS;
3789
3790 mutex_lock(&fs_info->balance_mutex);
3791 if (!fs_info->balance_ctl) {
3792 mutex_unlock(&fs_info->balance_mutex);
3793 return -ENOTCONN;
3794 }
3795
3796 atomic_inc(&fs_info->balance_cancel_req);
3797 /*
3798 * if we are running just wait and return, balance item is
3799 * deleted in btrfs_balance in this case
3800 */
3801 if (atomic_read(&fs_info->balance_running)) {
3802 mutex_unlock(&fs_info->balance_mutex);
3803 wait_event(fs_info->balance_wait_q,
3804 atomic_read(&fs_info->balance_running) == 0);
3805 mutex_lock(&fs_info->balance_mutex);
3806 } else {
3807 /* __cancel_balance needs volume_mutex */
3808 mutex_unlock(&fs_info->balance_mutex);
3809 mutex_lock(&fs_info->volume_mutex);
3810 mutex_lock(&fs_info->balance_mutex);
3811
3812 if (fs_info->balance_ctl)
3813 __cancel_balance(fs_info);
3814
3815 mutex_unlock(&fs_info->volume_mutex);
3816 }
3817
3818 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
3819 atomic_dec(&fs_info->balance_cancel_req);
3820 mutex_unlock(&fs_info->balance_mutex);
3821 return 0;
3822 }
3823
3824 static int btrfs_uuid_scan_kthread(void *data)
3825 {
3826 struct btrfs_fs_info *fs_info = data;
3827 struct btrfs_root *root = fs_info->tree_root;
3828 struct btrfs_key key;
3829 struct btrfs_key max_key;
3830 struct btrfs_path *path = NULL;
3831 int ret = 0;
3832 struct extent_buffer *eb;
3833 int slot;
3834 struct btrfs_root_item root_item;
3835 u32 item_size;
3836 struct btrfs_trans_handle *trans = NULL;
3837
3838 path = btrfs_alloc_path();
3839 if (!path) {
3840 ret = -ENOMEM;
3841 goto out;
3842 }
3843
3844 key.objectid = 0;
3845 key.type = BTRFS_ROOT_ITEM_KEY;
3846 key.offset = 0;
3847
3848 max_key.objectid = (u64)-1;
3849 max_key.type = BTRFS_ROOT_ITEM_KEY;
3850 max_key.offset = (u64)-1;
3851
3852 while (1) {
3853 ret = btrfs_search_forward(root, &key, path, 0);
3854 if (ret) {
3855 if (ret > 0)
3856 ret = 0;
3857 break;
3858 }
3859
3860 if (key.type != BTRFS_ROOT_ITEM_KEY ||
3861 (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
3862 key.objectid != BTRFS_FS_TREE_OBJECTID) ||
3863 key.objectid > BTRFS_LAST_FREE_OBJECTID)
3864 goto skip;
3865
3866 eb = path->nodes[0];
3867 slot = path->slots[0];
3868 item_size = btrfs_item_size_nr(eb, slot);
3869 if (item_size < sizeof(root_item))
3870 goto skip;
3871
3872 read_extent_buffer(eb, &root_item,
3873 btrfs_item_ptr_offset(eb, slot),
3874 (int)sizeof(root_item));
3875 if (btrfs_root_refs(&root_item) == 0)
3876 goto skip;
3877
3878 if (!btrfs_is_empty_uuid(root_item.uuid) ||
3879 !btrfs_is_empty_uuid(root_item.received_uuid)) {
3880 if (trans)
3881 goto update_tree;
3882
3883 btrfs_release_path(path);
3884 /*
3885 * 1 - subvol uuid item
3886 * 1 - received_subvol uuid item
3887 */
3888 trans = btrfs_start_transaction(fs_info->uuid_root, 2);
3889 if (IS_ERR(trans)) {
3890 ret = PTR_ERR(trans);
3891 break;
3892 }
3893 continue;
3894 } else {
3895 goto skip;
3896 }
3897 update_tree:
3898 if (!btrfs_is_empty_uuid(root_item.uuid)) {
3899 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3900 root_item.uuid,
3901 BTRFS_UUID_KEY_SUBVOL,
3902 key.objectid);
3903 if (ret < 0) {
3904 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3905 ret);
3906 break;
3907 }
3908 }
3909
3910 if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
3911 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3912 root_item.received_uuid,
3913 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
3914 key.objectid);
3915 if (ret < 0) {
3916 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3917 ret);
3918 break;
3919 }
3920 }
3921
3922 skip:
3923 if (trans) {
3924 ret = btrfs_end_transaction(trans, fs_info->uuid_root);
3925 trans = NULL;
3926 if (ret)
3927 break;
3928 }
3929
3930 btrfs_release_path(path);
3931 if (key.offset < (u64)-1) {
3932 key.offset++;
3933 } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
3934 key.offset = 0;
3935 key.type = BTRFS_ROOT_ITEM_KEY;
3936 } else if (key.objectid < (u64)-1) {
3937 key.offset = 0;
3938 key.type = BTRFS_ROOT_ITEM_KEY;
3939 key.objectid++;
3940 } else {
3941 break;
3942 }
3943 cond_resched();
3944 }
3945
3946 out:
3947 btrfs_free_path(path);
3948 if (trans && !IS_ERR(trans))
3949 btrfs_end_transaction(trans, fs_info->uuid_root);
3950 if (ret)
3951 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
3952 else
3953 fs_info->update_uuid_tree_gen = 1;
3954 up(&fs_info->uuid_tree_rescan_sem);
3955 return 0;
3956 }
3957
3958 /*
3959 * Callback for btrfs_uuid_tree_iterate().
3960 * returns:
3961 * 0 check succeeded, the entry is not outdated.
3962 * < 0 if an error occured.
3963 * > 0 if the check failed, which means the caller shall remove the entry.
3964 */
3965 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
3966 u8 *uuid, u8 type, u64 subid)
3967 {
3968 struct btrfs_key key;
3969 int ret = 0;
3970 struct btrfs_root *subvol_root;
3971
3972 if (type != BTRFS_UUID_KEY_SUBVOL &&
3973 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
3974 goto out;
3975
3976 key.objectid = subid;
3977 key.type = BTRFS_ROOT_ITEM_KEY;
3978 key.offset = (u64)-1;
3979 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
3980 if (IS_ERR(subvol_root)) {
3981 ret = PTR_ERR(subvol_root);
3982 if (ret == -ENOENT)
3983 ret = 1;
3984 goto out;
3985 }
3986
3987 switch (type) {
3988 case BTRFS_UUID_KEY_SUBVOL:
3989 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
3990 ret = 1;
3991 break;
3992 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
3993 if (memcmp(uuid, subvol_root->root_item.received_uuid,
3994 BTRFS_UUID_SIZE))
3995 ret = 1;
3996 break;
3997 }
3998
3999 out:
4000 return ret;
4001 }
4002
4003 static int btrfs_uuid_rescan_kthread(void *data)
4004 {
4005 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
4006 int ret;
4007
4008 /*
4009 * 1st step is to iterate through the existing UUID tree and
4010 * to delete all entries that contain outdated data.
4011 * 2nd step is to add all missing entries to the UUID tree.
4012 */
4013 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
4014 if (ret < 0) {
4015 btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
4016 up(&fs_info->uuid_tree_rescan_sem);
4017 return ret;
4018 }
4019 return btrfs_uuid_scan_kthread(data);
4020 }
4021
4022 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
4023 {
4024 struct btrfs_trans_handle *trans;
4025 struct btrfs_root *tree_root = fs_info->tree_root;
4026 struct btrfs_root *uuid_root;
4027 struct task_struct *task;
4028 int ret;
4029
4030 /*
4031 * 1 - root node
4032 * 1 - root item
4033 */
4034 trans = btrfs_start_transaction(tree_root, 2);
4035 if (IS_ERR(trans))
4036 return PTR_ERR(trans);
4037
4038 uuid_root = btrfs_create_tree(trans, fs_info,
4039 BTRFS_UUID_TREE_OBJECTID);
4040 if (IS_ERR(uuid_root)) {
4041 ret = PTR_ERR(uuid_root);
4042 btrfs_abort_transaction(trans, tree_root, ret);
4043 return ret;
4044 }
4045
4046 fs_info->uuid_root = uuid_root;
4047
4048 ret = btrfs_commit_transaction(trans, tree_root);
4049 if (ret)
4050 return ret;
4051
4052 down(&fs_info->uuid_tree_rescan_sem);
4053 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
4054 if (IS_ERR(task)) {
4055 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
4056 btrfs_warn(fs_info, "failed to start uuid_scan task");
4057 up(&fs_info->uuid_tree_rescan_sem);
4058 return PTR_ERR(task);
4059 }
4060
4061 return 0;
4062 }
4063
4064 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
4065 {
4066 struct task_struct *task;
4067
4068 down(&fs_info->uuid_tree_rescan_sem);
4069 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
4070 if (IS_ERR(task)) {
4071 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
4072 btrfs_warn(fs_info, "failed to start uuid_rescan task");
4073 up(&fs_info->uuid_tree_rescan_sem);
4074 return PTR_ERR(task);
4075 }
4076
4077 return 0;
4078 }
4079
4080 /*
4081 * shrinking a device means finding all of the device extents past
4082 * the new size, and then following the back refs to the chunks.
4083 * The chunk relocation code actually frees the device extent
4084 */
4085 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
4086 {
4087 struct btrfs_trans_handle *trans;
4088 struct btrfs_root *root = device->dev_root;
4089 struct btrfs_dev_extent *dev_extent = NULL;
4090 struct btrfs_path *path;
4091 u64 length;
4092 u64 chunk_offset;
4093 int ret;
4094 int slot;
4095 int failed = 0;
4096 bool retried = false;
4097 bool checked_pending_chunks = false;
4098 struct extent_buffer *l;
4099 struct btrfs_key key;
4100 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4101 u64 old_total = btrfs_super_total_bytes(super_copy);
4102 u64 old_size = btrfs_device_get_total_bytes(device);
4103 u64 diff = old_size - new_size;
4104
4105 if (device->is_tgtdev_for_dev_replace)
4106 return -EINVAL;
4107
4108 path = btrfs_alloc_path();
4109 if (!path)
4110 return -ENOMEM;
4111
4112 path->reada = 2;
4113
4114 lock_chunks(root);
4115
4116 btrfs_device_set_total_bytes(device, new_size);
4117 if (device->writeable) {
4118 device->fs_devices->total_rw_bytes -= diff;
4119 spin_lock(&root->fs_info->free_chunk_lock);
4120 root->fs_info->free_chunk_space -= diff;
4121 spin_unlock(&root->fs_info->free_chunk_lock);
4122 }
4123 unlock_chunks(root);
4124
4125 again:
4126 key.objectid = device->devid;
4127 key.offset = (u64)-1;
4128 key.type = BTRFS_DEV_EXTENT_KEY;
4129
4130 do {
4131 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
4132 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4133 if (ret < 0) {
4134 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4135 goto done;
4136 }
4137
4138 ret = btrfs_previous_item(root, path, 0, key.type);
4139 if (ret)
4140 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4141 if (ret < 0)
4142 goto done;
4143 if (ret) {
4144 ret = 0;
4145 btrfs_release_path(path);
4146 break;
4147 }
4148
4149 l = path->nodes[0];
4150 slot = path->slots[0];
4151 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
4152
4153 if (key.objectid != device->devid) {
4154 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4155 btrfs_release_path(path);
4156 break;
4157 }
4158
4159 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
4160 length = btrfs_dev_extent_length(l, dev_extent);
4161
4162 if (key.offset + length <= new_size) {
4163 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4164 btrfs_release_path(path);
4165 break;
4166 }
4167
4168 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
4169 btrfs_release_path(path);
4170
4171 ret = btrfs_relocate_chunk(root, chunk_offset);
4172 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4173 if (ret && ret != -ENOSPC)
4174 goto done;
4175 if (ret == -ENOSPC)
4176 failed++;
4177 } while (key.offset-- > 0);
4178
4179 if (failed && !retried) {
4180 failed = 0;
4181 retried = true;
4182 goto again;
4183 } else if (failed && retried) {
4184 ret = -ENOSPC;
4185 goto done;
4186 }
4187
4188 /* Shrinking succeeded, else we would be at "done". */
4189 trans = btrfs_start_transaction(root, 0);
4190 if (IS_ERR(trans)) {
4191 ret = PTR_ERR(trans);
4192 goto done;
4193 }
4194
4195 lock_chunks(root);
4196
4197 /*
4198 * We checked in the above loop all device extents that were already in
4199 * the device tree. However before we have updated the device's
4200 * total_bytes to the new size, we might have had chunk allocations that
4201 * have not complete yet (new block groups attached to transaction
4202 * handles), and therefore their device extents were not yet in the
4203 * device tree and we missed them in the loop above. So if we have any
4204 * pending chunk using a device extent that overlaps the device range
4205 * that we can not use anymore, commit the current transaction and
4206 * repeat the search on the device tree - this way we guarantee we will
4207 * not have chunks using device extents that end beyond 'new_size'.
4208 */
4209 if (!checked_pending_chunks) {
4210 u64 start = new_size;
4211 u64 len = old_size - new_size;
4212
4213 if (contains_pending_extent(trans->transaction, device,
4214 &start, len)) {
4215 unlock_chunks(root);
4216 checked_pending_chunks = true;
4217 failed = 0;
4218 retried = false;
4219 ret = btrfs_commit_transaction(trans, root);
4220 if (ret)
4221 goto done;
4222 goto again;
4223 }
4224 }
4225
4226 btrfs_device_set_disk_total_bytes(device, new_size);
4227 if (list_empty(&device->resized_list))
4228 list_add_tail(&device->resized_list,
4229 &root->fs_info->fs_devices->resized_devices);
4230
4231 WARN_ON(diff > old_total);
4232 btrfs_set_super_total_bytes(super_copy, old_total - diff);
4233 unlock_chunks(root);
4234
4235 /* Now btrfs_update_device() will change the on-disk size. */
4236 ret = btrfs_update_device(trans, device);
4237 btrfs_end_transaction(trans, root);
4238 done:
4239 btrfs_free_path(path);
4240 if (ret) {
4241 lock_chunks(root);
4242 btrfs_device_set_total_bytes(device, old_size);
4243 if (device->writeable)
4244 device->fs_devices->total_rw_bytes += diff;
4245 spin_lock(&root->fs_info->free_chunk_lock);
4246 root->fs_info->free_chunk_space += diff;
4247 spin_unlock(&root->fs_info->free_chunk_lock);
4248 unlock_chunks(root);
4249 }
4250 return ret;
4251 }
4252
4253 static int btrfs_add_system_chunk(struct btrfs_root *root,
4254 struct btrfs_key *key,
4255 struct btrfs_chunk *chunk, int item_size)
4256 {
4257 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4258 struct btrfs_disk_key disk_key;
4259 u32 array_size;
4260 u8 *ptr;
4261
4262 lock_chunks(root);
4263 array_size = btrfs_super_sys_array_size(super_copy);
4264 if (array_size + item_size + sizeof(disk_key)
4265 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
4266 unlock_chunks(root);
4267 return -EFBIG;
4268 }
4269
4270 ptr = super_copy->sys_chunk_array + array_size;
4271 btrfs_cpu_key_to_disk(&disk_key, key);
4272 memcpy(ptr, &disk_key, sizeof(disk_key));
4273 ptr += sizeof(disk_key);
4274 memcpy(ptr, chunk, item_size);
4275 item_size += sizeof(disk_key);
4276 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
4277 unlock_chunks(root);
4278
4279 return 0;
4280 }
4281
4282 /*
4283 * sort the devices in descending order by max_avail, total_avail
4284 */
4285 static int btrfs_cmp_device_info(const void *a, const void *b)
4286 {
4287 const struct btrfs_device_info *di_a = a;
4288 const struct btrfs_device_info *di_b = b;
4289
4290 if (di_a->max_avail > di_b->max_avail)
4291 return -1;
4292 if (di_a->max_avail < di_b->max_avail)
4293 return 1;
4294 if (di_a->total_avail > di_b->total_avail)
4295 return -1;
4296 if (di_a->total_avail < di_b->total_avail)
4297 return 1;
4298 return 0;
4299 }
4300
4301 static const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
4302 [BTRFS_RAID_RAID10] = {
4303 .sub_stripes = 2,
4304 .dev_stripes = 1,
4305 .devs_max = 0, /* 0 == as many as possible */
4306 .devs_min = 4,
4307 .devs_increment = 2,
4308 .ncopies = 2,
4309 },
4310 [BTRFS_RAID_RAID1] = {
4311 .sub_stripes = 1,
4312 .dev_stripes = 1,
4313 .devs_max = 2,
4314 .devs_min = 2,
4315 .devs_increment = 2,
4316 .ncopies = 2,
4317 },
4318 [BTRFS_RAID_DUP] = {
4319 .sub_stripes = 1,
4320 .dev_stripes = 2,
4321 .devs_max = 1,
4322 .devs_min = 1,
4323 .devs_increment = 1,
4324 .ncopies = 2,
4325 },
4326 [BTRFS_RAID_RAID0] = {
4327 .sub_stripes = 1,
4328 .dev_stripes = 1,
4329 .devs_max = 0,
4330 .devs_min = 2,
4331 .devs_increment = 1,
4332 .ncopies = 1,
4333 },
4334 [BTRFS_RAID_SINGLE] = {
4335 .sub_stripes = 1,
4336 .dev_stripes = 1,
4337 .devs_max = 1,
4338 .devs_min = 1,
4339 .devs_increment = 1,
4340 .ncopies = 1,
4341 },
4342 [BTRFS_RAID_RAID5] = {
4343 .sub_stripes = 1,
4344 .dev_stripes = 1,
4345 .devs_max = 0,
4346 .devs_min = 2,
4347 .devs_increment = 1,
4348 .ncopies = 2,
4349 },
4350 [BTRFS_RAID_RAID6] = {
4351 .sub_stripes = 1,
4352 .dev_stripes = 1,
4353 .devs_max = 0,
4354 .devs_min = 3,
4355 .devs_increment = 1,
4356 .ncopies = 3,
4357 },
4358 };
4359
4360 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
4361 {
4362 /* TODO allow them to set a preferred stripe size */
4363 return 64 * 1024;
4364 }
4365
4366 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
4367 {
4368 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
4369 return;
4370
4371 btrfs_set_fs_incompat(info, RAID56);
4372 }
4373
4374 #define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \
4375 - sizeof(struct btrfs_item) \
4376 - sizeof(struct btrfs_chunk)) \
4377 / sizeof(struct btrfs_stripe) + 1)
4378
4379 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
4380 - 2 * sizeof(struct btrfs_disk_key) \
4381 - 2 * sizeof(struct btrfs_chunk)) \
4382 / sizeof(struct btrfs_stripe) + 1)
4383
4384 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4385 struct btrfs_root *extent_root, u64 start,
4386 u64 type)
4387 {
4388 struct btrfs_fs_info *info = extent_root->fs_info;
4389 struct btrfs_fs_devices *fs_devices = info->fs_devices;
4390 struct list_head *cur;
4391 struct map_lookup *map = NULL;
4392 struct extent_map_tree *em_tree;
4393 struct extent_map *em;
4394 struct btrfs_device_info *devices_info = NULL;
4395 u64 total_avail;
4396 int num_stripes; /* total number of stripes to allocate */
4397 int data_stripes; /* number of stripes that count for
4398 block group size */
4399 int sub_stripes; /* sub_stripes info for map */
4400 int dev_stripes; /* stripes per dev */
4401 int devs_max; /* max devs to use */
4402 int devs_min; /* min devs needed */
4403 int devs_increment; /* ndevs has to be a multiple of this */
4404 int ncopies; /* how many copies to data has */
4405 int ret;
4406 u64 max_stripe_size;
4407 u64 max_chunk_size;
4408 u64 stripe_size;
4409 u64 num_bytes;
4410 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
4411 int ndevs;
4412 int i;
4413 int j;
4414 int index;
4415
4416 BUG_ON(!alloc_profile_is_valid(type, 0));
4417
4418 if (list_empty(&fs_devices->alloc_list))
4419 return -ENOSPC;
4420
4421 index = __get_raid_index(type);
4422
4423 sub_stripes = btrfs_raid_array[index].sub_stripes;
4424 dev_stripes = btrfs_raid_array[index].dev_stripes;
4425 devs_max = btrfs_raid_array[index].devs_max;
4426 devs_min = btrfs_raid_array[index].devs_min;
4427 devs_increment = btrfs_raid_array[index].devs_increment;
4428 ncopies = btrfs_raid_array[index].ncopies;
4429
4430 if (type & BTRFS_BLOCK_GROUP_DATA) {
4431 max_stripe_size = 1024 * 1024 * 1024;
4432 max_chunk_size = 10 * max_stripe_size;
4433 if (!devs_max)
4434 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4435 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
4436 /* for larger filesystems, use larger metadata chunks */
4437 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
4438 max_stripe_size = 1024 * 1024 * 1024;
4439 else
4440 max_stripe_size = 256 * 1024 * 1024;
4441 max_chunk_size = max_stripe_size;
4442 if (!devs_max)
4443 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4444 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
4445 max_stripe_size = 32 * 1024 * 1024;
4446 max_chunk_size = 2 * max_stripe_size;
4447 if (!devs_max)
4448 devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
4449 } else {
4450 btrfs_err(info, "invalid chunk type 0x%llx requested",
4451 type);
4452 BUG_ON(1);
4453 }
4454
4455 /* we don't want a chunk larger than 10% of writeable space */
4456 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
4457 max_chunk_size);
4458
4459 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
4460 GFP_NOFS);
4461 if (!devices_info)
4462 return -ENOMEM;
4463
4464 cur = fs_devices->alloc_list.next;
4465
4466 /*
4467 * in the first pass through the devices list, we gather information
4468 * about the available holes on each device.
4469 */
4470 ndevs = 0;
4471 while (cur != &fs_devices->alloc_list) {
4472 struct btrfs_device *device;
4473 u64 max_avail;
4474 u64 dev_offset;
4475
4476 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
4477
4478 cur = cur->next;
4479
4480 if (!device->writeable) {
4481 WARN(1, KERN_ERR
4482 "BTRFS: read-only device in alloc_list\n");
4483 continue;
4484 }
4485
4486 if (!device->in_fs_metadata ||
4487 device->is_tgtdev_for_dev_replace)
4488 continue;
4489
4490 if (device->total_bytes > device->bytes_used)
4491 total_avail = device->total_bytes - device->bytes_used;
4492 else
4493 total_avail = 0;
4494
4495 /* If there is no space on this device, skip it. */
4496 if (total_avail == 0)
4497 continue;
4498
4499 ret = find_free_dev_extent(trans, device,
4500 max_stripe_size * dev_stripes,
4501 &dev_offset, &max_avail);
4502 if (ret && ret != -ENOSPC)
4503 goto error;
4504
4505 if (ret == 0)
4506 max_avail = max_stripe_size * dev_stripes;
4507
4508 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
4509 continue;
4510
4511 if (ndevs == fs_devices->rw_devices) {
4512 WARN(1, "%s: found more than %llu devices\n",
4513 __func__, fs_devices->rw_devices);
4514 break;
4515 }
4516 devices_info[ndevs].dev_offset = dev_offset;
4517 devices_info[ndevs].max_avail = max_avail;
4518 devices_info[ndevs].total_avail = total_avail;
4519 devices_info[ndevs].dev = device;
4520 ++ndevs;
4521 }
4522
4523 /*
4524 * now sort the devices by hole size / available space
4525 */
4526 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
4527 btrfs_cmp_device_info, NULL);
4528
4529 /* round down to number of usable stripes */
4530 ndevs -= ndevs % devs_increment;
4531
4532 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
4533 ret = -ENOSPC;
4534 goto error;
4535 }
4536
4537 if (devs_max && ndevs > devs_max)
4538 ndevs = devs_max;
4539 /*
4540 * the primary goal is to maximize the number of stripes, so use as many
4541 * devices as possible, even if the stripes are not maximum sized.
4542 */
4543 stripe_size = devices_info[ndevs-1].max_avail;
4544 num_stripes = ndevs * dev_stripes;
4545
4546 /*
4547 * this will have to be fixed for RAID1 and RAID10 over
4548 * more drives
4549 */
4550 data_stripes = num_stripes / ncopies;
4551
4552 if (type & BTRFS_BLOCK_GROUP_RAID5) {
4553 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
4554 btrfs_super_stripesize(info->super_copy));
4555 data_stripes = num_stripes - 1;
4556 }
4557 if (type & BTRFS_BLOCK_GROUP_RAID6) {
4558 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
4559 btrfs_super_stripesize(info->super_copy));
4560 data_stripes = num_stripes - 2;
4561 }
4562
4563 /*
4564 * Use the number of data stripes to figure out how big this chunk
4565 * is really going to be in terms of logical address space,
4566 * and compare that answer with the max chunk size
4567 */
4568 if (stripe_size * data_stripes > max_chunk_size) {
4569 u64 mask = (1ULL << 24) - 1;
4570
4571 stripe_size = div_u64(max_chunk_size, data_stripes);
4572
4573 /* bump the answer up to a 16MB boundary */
4574 stripe_size = (stripe_size + mask) & ~mask;
4575
4576 /* but don't go higher than the limits we found
4577 * while searching for free extents
4578 */
4579 if (stripe_size > devices_info[ndevs-1].max_avail)
4580 stripe_size = devices_info[ndevs-1].max_avail;
4581 }
4582
4583 stripe_size = div_u64(stripe_size, dev_stripes);
4584
4585 /* align to BTRFS_STRIPE_LEN */
4586 stripe_size = div_u64(stripe_size, raid_stripe_len);
4587 stripe_size *= raid_stripe_len;
4588
4589 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4590 if (!map) {
4591 ret = -ENOMEM;
4592 goto error;
4593 }
4594 map->num_stripes = num_stripes;
4595
4596 for (i = 0; i < ndevs; ++i) {
4597 for (j = 0; j < dev_stripes; ++j) {
4598 int s = i * dev_stripes + j;
4599 map->stripes[s].dev = devices_info[i].dev;
4600 map->stripes[s].physical = devices_info[i].dev_offset +
4601 j * stripe_size;
4602 }
4603 }
4604 map->sector_size = extent_root->sectorsize;
4605 map->stripe_len = raid_stripe_len;
4606 map->io_align = raid_stripe_len;
4607 map->io_width = raid_stripe_len;
4608 map->type = type;
4609 map->sub_stripes = sub_stripes;
4610
4611 num_bytes = stripe_size * data_stripes;
4612
4613 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
4614
4615 em = alloc_extent_map();
4616 if (!em) {
4617 kfree(map);
4618 ret = -ENOMEM;
4619 goto error;
4620 }
4621 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
4622 em->bdev = (struct block_device *)map;
4623 em->start = start;
4624 em->len = num_bytes;
4625 em->block_start = 0;
4626 em->block_len = em->len;
4627 em->orig_block_len = stripe_size;
4628
4629 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4630 write_lock(&em_tree->lock);
4631 ret = add_extent_mapping(em_tree, em, 0);
4632 if (!ret) {
4633 list_add_tail(&em->list, &trans->transaction->pending_chunks);
4634 atomic_inc(&em->refs);
4635 }
4636 write_unlock(&em_tree->lock);
4637 if (ret) {
4638 free_extent_map(em);
4639 goto error;
4640 }
4641
4642 ret = btrfs_make_block_group(trans, extent_root, 0, type,
4643 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4644 start, num_bytes);
4645 if (ret)
4646 goto error_del_extent;
4647
4648 for (i = 0; i < map->num_stripes; i++) {
4649 num_bytes = map->stripes[i].dev->bytes_used + stripe_size;
4650 btrfs_device_set_bytes_used(map->stripes[i].dev, num_bytes);
4651 }
4652
4653 spin_lock(&extent_root->fs_info->free_chunk_lock);
4654 extent_root->fs_info->free_chunk_space -= (stripe_size *
4655 map->num_stripes);
4656 spin_unlock(&extent_root->fs_info->free_chunk_lock);
4657
4658 free_extent_map(em);
4659 check_raid56_incompat_flag(extent_root->fs_info, type);
4660
4661 kfree(devices_info);
4662 return 0;
4663
4664 error_del_extent:
4665 write_lock(&em_tree->lock);
4666 remove_extent_mapping(em_tree, em);
4667 write_unlock(&em_tree->lock);
4668
4669 /* One for our allocation */
4670 free_extent_map(em);
4671 /* One for the tree reference */
4672 free_extent_map(em);
4673 /* One for the pending_chunks list reference */
4674 free_extent_map(em);
4675 error:
4676 kfree(devices_info);
4677 return ret;
4678 }
4679
4680 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
4681 struct btrfs_root *extent_root,
4682 u64 chunk_offset, u64 chunk_size)
4683 {
4684 struct btrfs_key key;
4685 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
4686 struct btrfs_device *device;
4687 struct btrfs_chunk *chunk;
4688 struct btrfs_stripe *stripe;
4689 struct extent_map_tree *em_tree;
4690 struct extent_map *em;
4691 struct map_lookup *map;
4692 size_t item_size;
4693 u64 dev_offset;
4694 u64 stripe_size;
4695 int i = 0;
4696 int ret;
4697
4698 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4699 read_lock(&em_tree->lock);
4700 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
4701 read_unlock(&em_tree->lock);
4702
4703 if (!em) {
4704 btrfs_crit(extent_root->fs_info, "unable to find logical "
4705 "%Lu len %Lu", chunk_offset, chunk_size);
4706 return -EINVAL;
4707 }
4708
4709 if (em->start != chunk_offset || em->len != chunk_size) {
4710 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted"
4711 " %Lu-%Lu, found %Lu-%Lu", chunk_offset,
4712 chunk_size, em->start, em->len);
4713 free_extent_map(em);
4714 return -EINVAL;
4715 }
4716
4717 map = (struct map_lookup *)em->bdev;
4718 item_size = btrfs_chunk_item_size(map->num_stripes);
4719 stripe_size = em->orig_block_len;
4720
4721 chunk = kzalloc(item_size, GFP_NOFS);
4722 if (!chunk) {
4723 ret = -ENOMEM;
4724 goto out;
4725 }
4726
4727 for (i = 0; i < map->num_stripes; i++) {
4728 device = map->stripes[i].dev;
4729 dev_offset = map->stripes[i].physical;
4730
4731 ret = btrfs_update_device(trans, device);
4732 if (ret)
4733 goto out;
4734 ret = btrfs_alloc_dev_extent(trans, device,
4735 chunk_root->root_key.objectid,
4736 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4737 chunk_offset, dev_offset,
4738 stripe_size);
4739 if (ret)
4740 goto out;
4741 }
4742
4743 stripe = &chunk->stripe;
4744 for (i = 0; i < map->num_stripes; i++) {
4745 device = map->stripes[i].dev;
4746 dev_offset = map->stripes[i].physical;
4747
4748 btrfs_set_stack_stripe_devid(stripe, device->devid);
4749 btrfs_set_stack_stripe_offset(stripe, dev_offset);
4750 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
4751 stripe++;
4752 }
4753
4754 btrfs_set_stack_chunk_length(chunk, chunk_size);
4755 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
4756 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
4757 btrfs_set_stack_chunk_type(chunk, map->type);
4758 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
4759 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
4760 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
4761 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
4762 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
4763
4764 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4765 key.type = BTRFS_CHUNK_ITEM_KEY;
4766 key.offset = chunk_offset;
4767
4768 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
4769 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
4770 /*
4771 * TODO: Cleanup of inserted chunk root in case of
4772 * failure.
4773 */
4774 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
4775 item_size);
4776 }
4777
4778 out:
4779 kfree(chunk);
4780 free_extent_map(em);
4781 return ret;
4782 }
4783
4784 /*
4785 * Chunk allocation falls into two parts. The first part does works
4786 * that make the new allocated chunk useable, but not do any operation
4787 * that modifies the chunk tree. The second part does the works that
4788 * require modifying the chunk tree. This division is important for the
4789 * bootstrap process of adding storage to a seed btrfs.
4790 */
4791 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4792 struct btrfs_root *extent_root, u64 type)
4793 {
4794 u64 chunk_offset;
4795
4796 ASSERT(mutex_is_locked(&extent_root->fs_info->chunk_mutex));
4797 chunk_offset = find_next_chunk(extent_root->fs_info);
4798 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type);
4799 }
4800
4801 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
4802 struct btrfs_root *root,
4803 struct btrfs_device *device)
4804 {
4805 u64 chunk_offset;
4806 u64 sys_chunk_offset;
4807 u64 alloc_profile;
4808 struct btrfs_fs_info *fs_info = root->fs_info;
4809 struct btrfs_root *extent_root = fs_info->extent_root;
4810 int ret;
4811
4812 chunk_offset = find_next_chunk(fs_info);
4813 alloc_profile = btrfs_get_alloc_profile(extent_root, 0);
4814 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset,
4815 alloc_profile);
4816 if (ret)
4817 return ret;
4818
4819 sys_chunk_offset = find_next_chunk(root->fs_info);
4820 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
4821 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset,
4822 alloc_profile);
4823 return ret;
4824 }
4825
4826 static inline int btrfs_chunk_max_errors(struct map_lookup *map)
4827 {
4828 int max_errors;
4829
4830 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
4831 BTRFS_BLOCK_GROUP_RAID10 |
4832 BTRFS_BLOCK_GROUP_RAID5 |
4833 BTRFS_BLOCK_GROUP_DUP)) {
4834 max_errors = 1;
4835 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
4836 max_errors = 2;
4837 } else {
4838 max_errors = 0;
4839 }
4840
4841 return max_errors;
4842 }
4843
4844 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
4845 {
4846 struct extent_map *em;
4847 struct map_lookup *map;
4848 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4849 int readonly = 0;
4850 int miss_ndevs = 0;
4851 int i;
4852
4853 read_lock(&map_tree->map_tree.lock);
4854 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
4855 read_unlock(&map_tree->map_tree.lock);
4856 if (!em)
4857 return 1;
4858
4859 map = (struct map_lookup *)em->bdev;
4860 for (i = 0; i < map->num_stripes; i++) {
4861 if (map->stripes[i].dev->missing) {
4862 miss_ndevs++;
4863 continue;
4864 }
4865
4866 if (!map->stripes[i].dev->writeable) {
4867 readonly = 1;
4868 goto end;
4869 }
4870 }
4871
4872 /*
4873 * If the number of missing devices is larger than max errors,
4874 * we can not write the data into that chunk successfully, so
4875 * set it readonly.
4876 */
4877 if (miss_ndevs > btrfs_chunk_max_errors(map))
4878 readonly = 1;
4879 end:
4880 free_extent_map(em);
4881 return readonly;
4882 }
4883
4884 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
4885 {
4886 extent_map_tree_init(&tree->map_tree);
4887 }
4888
4889 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
4890 {
4891 struct extent_map *em;
4892
4893 while (1) {
4894 write_lock(&tree->map_tree.lock);
4895 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
4896 if (em)
4897 remove_extent_mapping(&tree->map_tree, em);
4898 write_unlock(&tree->map_tree.lock);
4899 if (!em)
4900 break;
4901 /* once for us */
4902 free_extent_map(em);
4903 /* once for the tree */
4904 free_extent_map(em);
4905 }
4906 }
4907
4908 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
4909 {
4910 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4911 struct extent_map *em;
4912 struct map_lookup *map;
4913 struct extent_map_tree *em_tree = &map_tree->map_tree;
4914 int ret;
4915
4916 read_lock(&em_tree->lock);
4917 em = lookup_extent_mapping(em_tree, logical, len);
4918 read_unlock(&em_tree->lock);
4919
4920 /*
4921 * We could return errors for these cases, but that could get ugly and
4922 * we'd probably do the same thing which is just not do anything else
4923 * and exit, so return 1 so the callers don't try to use other copies.
4924 */
4925 if (!em) {
4926 btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
4927 logical+len);
4928 return 1;
4929 }
4930
4931 if (em->start > logical || em->start + em->len < logical) {
4932 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got "
4933 "%Lu-%Lu", logical, logical+len, em->start,
4934 em->start + em->len);
4935 free_extent_map(em);
4936 return 1;
4937 }
4938
4939 map = (struct map_lookup *)em->bdev;
4940 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
4941 ret = map->num_stripes;
4942 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
4943 ret = map->sub_stripes;
4944 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
4945 ret = 2;
4946 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
4947 ret = 3;
4948 else
4949 ret = 1;
4950 free_extent_map(em);
4951
4952 btrfs_dev_replace_lock(&fs_info->dev_replace);
4953 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
4954 ret++;
4955 btrfs_dev_replace_unlock(&fs_info->dev_replace);
4956
4957 return ret;
4958 }
4959
4960 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
4961 struct btrfs_mapping_tree *map_tree,
4962 u64 logical)
4963 {
4964 struct extent_map *em;
4965 struct map_lookup *map;
4966 struct extent_map_tree *em_tree = &map_tree->map_tree;
4967 unsigned long len = root->sectorsize;
4968
4969 read_lock(&em_tree->lock);
4970 em = lookup_extent_mapping(em_tree, logical, len);
4971 read_unlock(&em_tree->lock);
4972 BUG_ON(!em);
4973
4974 BUG_ON(em->start > logical || em->start + em->len < logical);
4975 map = (struct map_lookup *)em->bdev;
4976 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
4977 len = map->stripe_len * nr_data_stripes(map);
4978 free_extent_map(em);
4979 return len;
4980 }
4981
4982 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
4983 u64 logical, u64 len, int mirror_num)
4984 {
4985 struct extent_map *em;
4986 struct map_lookup *map;
4987 struct extent_map_tree *em_tree = &map_tree->map_tree;
4988 int ret = 0;
4989
4990 read_lock(&em_tree->lock);
4991 em = lookup_extent_mapping(em_tree, logical, len);
4992 read_unlock(&em_tree->lock);
4993 BUG_ON(!em);
4994
4995 BUG_ON(em->start > logical || em->start + em->len < logical);
4996 map = (struct map_lookup *)em->bdev;
4997 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
4998 ret = 1;
4999 free_extent_map(em);
5000 return ret;
5001 }
5002
5003 static int find_live_mirror(struct btrfs_fs_info *fs_info,
5004 struct map_lookup *map, int first, int num,
5005 int optimal, int dev_replace_is_ongoing)
5006 {
5007 int i;
5008 int tolerance;
5009 struct btrfs_device *srcdev;
5010
5011 if (dev_replace_is_ongoing &&
5012 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
5013 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
5014 srcdev = fs_info->dev_replace.srcdev;
5015 else
5016 srcdev = NULL;
5017
5018 /*
5019 * try to avoid the drive that is the source drive for a
5020 * dev-replace procedure, only choose it if no other non-missing
5021 * mirror is available
5022 */
5023 for (tolerance = 0; tolerance < 2; tolerance++) {
5024 if (map->stripes[optimal].dev->bdev &&
5025 (tolerance || map->stripes[optimal].dev != srcdev))
5026 return optimal;
5027 for (i = first; i < first + num; i++) {
5028 if (map->stripes[i].dev->bdev &&
5029 (tolerance || map->stripes[i].dev != srcdev))
5030 return i;
5031 }
5032 }
5033
5034 /* we couldn't find one that doesn't fail. Just return something
5035 * and the io error handling code will clean up eventually
5036 */
5037 return optimal;
5038 }
5039
5040 static inline int parity_smaller(u64 a, u64 b)
5041 {
5042 return a > b;
5043 }
5044
5045 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
5046 static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes)
5047 {
5048 struct btrfs_bio_stripe s;
5049 int i;
5050 u64 l;
5051 int again = 1;
5052
5053 while (again) {
5054 again = 0;
5055 for (i = 0; i < num_stripes - 1; i++) {
5056 if (parity_smaller(bbio->raid_map[i],
5057 bbio->raid_map[i+1])) {
5058 s = bbio->stripes[i];
5059 l = bbio->raid_map[i];
5060 bbio->stripes[i] = bbio->stripes[i+1];
5061 bbio->raid_map[i] = bbio->raid_map[i+1];
5062 bbio->stripes[i+1] = s;
5063 bbio->raid_map[i+1] = l;
5064
5065 again = 1;
5066 }
5067 }
5068 }
5069 }
5070
5071 static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
5072 {
5073 struct btrfs_bio *bbio = kzalloc(
5074 /* the size of the btrfs_bio */
5075 sizeof(struct btrfs_bio) +
5076 /* plus the variable array for the stripes */
5077 sizeof(struct btrfs_bio_stripe) * (total_stripes) +
5078 /* plus the variable array for the tgt dev */
5079 sizeof(int) * (real_stripes) +
5080 /*
5081 * plus the raid_map, which includes both the tgt dev
5082 * and the stripes
5083 */
5084 sizeof(u64) * (total_stripes),
5085 GFP_NOFS|__GFP_NOFAIL);
5086
5087 atomic_set(&bbio->error, 0);
5088 atomic_set(&bbio->refs, 1);
5089
5090 return bbio;
5091 }
5092
5093 void btrfs_get_bbio(struct btrfs_bio *bbio)
5094 {
5095 WARN_ON(!atomic_read(&bbio->refs));
5096 atomic_inc(&bbio->refs);
5097 }
5098
5099 void btrfs_put_bbio(struct btrfs_bio *bbio)
5100 {
5101 if (!bbio)
5102 return;
5103 if (atomic_dec_and_test(&bbio->refs))
5104 kfree(bbio);
5105 }
5106
5107 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5108 u64 logical, u64 *length,
5109 struct btrfs_bio **bbio_ret,
5110 int mirror_num, int need_raid_map)
5111 {
5112 struct extent_map *em;
5113 struct map_lookup *map;
5114 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
5115 struct extent_map_tree *em_tree = &map_tree->map_tree;
5116 u64 offset;
5117 u64 stripe_offset;
5118 u64 stripe_end_offset;
5119 u64 stripe_nr;
5120 u64 stripe_nr_orig;
5121 u64 stripe_nr_end;
5122 u64 stripe_len;
5123 u32 stripe_index;
5124 int i;
5125 int ret = 0;
5126 int num_stripes;
5127 int max_errors = 0;
5128 int tgtdev_indexes = 0;
5129 struct btrfs_bio *bbio = NULL;
5130 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
5131 int dev_replace_is_ongoing = 0;
5132 int num_alloc_stripes;
5133 int patch_the_first_stripe_for_dev_replace = 0;
5134 u64 physical_to_patch_in_first_stripe = 0;
5135 u64 raid56_full_stripe_start = (u64)-1;
5136
5137 read_lock(&em_tree->lock);
5138 em = lookup_extent_mapping(em_tree, logical, *length);
5139 read_unlock(&em_tree->lock);
5140
5141 if (!em) {
5142 btrfs_crit(fs_info, "unable to find logical %llu len %llu",
5143 logical, *length);
5144 return -EINVAL;
5145 }
5146
5147 if (em->start > logical || em->start + em->len < logical) {
5148 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, "
5149 "found %Lu-%Lu", logical, em->start,
5150 em->start + em->len);
5151 free_extent_map(em);
5152 return -EINVAL;
5153 }
5154
5155 map = (struct map_lookup *)em->bdev;
5156 offset = logical - em->start;
5157
5158 stripe_len = map->stripe_len;
5159 stripe_nr = offset;
5160 /*
5161 * stripe_nr counts the total number of stripes we have to stride
5162 * to get to this block
5163 */
5164 stripe_nr = div64_u64(stripe_nr, stripe_len);
5165
5166 stripe_offset = stripe_nr * stripe_len;
5167 BUG_ON(offset < stripe_offset);
5168
5169 /* stripe_offset is the offset of this block in its stripe*/
5170 stripe_offset = offset - stripe_offset;
5171
5172 /* if we're here for raid56, we need to know the stripe aligned start */
5173 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5174 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
5175 raid56_full_stripe_start = offset;
5176
5177 /* allow a write of a full stripe, but make sure we don't
5178 * allow straddling of stripes
5179 */
5180 raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
5181 full_stripe_len);
5182 raid56_full_stripe_start *= full_stripe_len;
5183 }
5184
5185 if (rw & REQ_DISCARD) {
5186 /* we don't discard raid56 yet */
5187 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5188 ret = -EOPNOTSUPP;
5189 goto out;
5190 }
5191 *length = min_t(u64, em->len - offset, *length);
5192 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
5193 u64 max_len;
5194 /* For writes to RAID[56], allow a full stripeset across all disks.
5195 For other RAID types and for RAID[56] reads, just allow a single
5196 stripe (on a single disk). */
5197 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
5198 (rw & REQ_WRITE)) {
5199 max_len = stripe_len * nr_data_stripes(map) -
5200 (offset - raid56_full_stripe_start);
5201 } else {
5202 /* we limit the length of each bio to what fits in a stripe */
5203 max_len = stripe_len - stripe_offset;
5204 }
5205 *length = min_t(u64, em->len - offset, max_len);
5206 } else {
5207 *length = em->len - offset;
5208 }
5209
5210 /* This is for when we're called from btrfs_merge_bio_hook() and all
5211 it cares about is the length */
5212 if (!bbio_ret)
5213 goto out;
5214
5215 btrfs_dev_replace_lock(dev_replace);
5216 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
5217 if (!dev_replace_is_ongoing)
5218 btrfs_dev_replace_unlock(dev_replace);
5219
5220 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
5221 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
5222 dev_replace->tgtdev != NULL) {
5223 /*
5224 * in dev-replace case, for repair case (that's the only
5225 * case where the mirror is selected explicitly when
5226 * calling btrfs_map_block), blocks left of the left cursor
5227 * can also be read from the target drive.
5228 * For REQ_GET_READ_MIRRORS, the target drive is added as
5229 * the last one to the array of stripes. For READ, it also
5230 * needs to be supported using the same mirror number.
5231 * If the requested block is not left of the left cursor,
5232 * EIO is returned. This can happen because btrfs_num_copies()
5233 * returns one more in the dev-replace case.
5234 */
5235 u64 tmp_length = *length;
5236 struct btrfs_bio *tmp_bbio = NULL;
5237 int tmp_num_stripes;
5238 u64 srcdev_devid = dev_replace->srcdev->devid;
5239 int index_srcdev = 0;
5240 int found = 0;
5241 u64 physical_of_found = 0;
5242
5243 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
5244 logical, &tmp_length, &tmp_bbio, 0, 0);
5245 if (ret) {
5246 WARN_ON(tmp_bbio != NULL);
5247 goto out;
5248 }
5249
5250 tmp_num_stripes = tmp_bbio->num_stripes;
5251 if (mirror_num > tmp_num_stripes) {
5252 /*
5253 * REQ_GET_READ_MIRRORS does not contain this
5254 * mirror, that means that the requested area
5255 * is not left of the left cursor
5256 */
5257 ret = -EIO;
5258 btrfs_put_bbio(tmp_bbio);
5259 goto out;
5260 }
5261
5262 /*
5263 * process the rest of the function using the mirror_num
5264 * of the source drive. Therefore look it up first.
5265 * At the end, patch the device pointer to the one of the
5266 * target drive.
5267 */
5268 for (i = 0; i < tmp_num_stripes; i++) {
5269 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) {
5270 /*
5271 * In case of DUP, in order to keep it
5272 * simple, only add the mirror with the
5273 * lowest physical address
5274 */
5275 if (found &&
5276 physical_of_found <=
5277 tmp_bbio->stripes[i].physical)
5278 continue;
5279 index_srcdev = i;
5280 found = 1;
5281 physical_of_found =
5282 tmp_bbio->stripes[i].physical;
5283 }
5284 }
5285
5286 if (found) {
5287 mirror_num = index_srcdev + 1;
5288 patch_the_first_stripe_for_dev_replace = 1;
5289 physical_to_patch_in_first_stripe = physical_of_found;
5290 } else {
5291 WARN_ON(1);
5292 ret = -EIO;
5293 btrfs_put_bbio(tmp_bbio);
5294 goto out;
5295 }
5296
5297 btrfs_put_bbio(tmp_bbio);
5298 } else if (mirror_num > map->num_stripes) {
5299 mirror_num = 0;
5300 }
5301
5302 num_stripes = 1;
5303 stripe_index = 0;
5304 stripe_nr_orig = stripe_nr;
5305 stripe_nr_end = ALIGN(offset + *length, map->stripe_len);
5306 stripe_nr_end = div_u64(stripe_nr_end, map->stripe_len);
5307 stripe_end_offset = stripe_nr_end * map->stripe_len -
5308 (offset + *length);
5309
5310 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5311 if (rw & REQ_DISCARD)
5312 num_stripes = min_t(u64, map->num_stripes,
5313 stripe_nr_end - stripe_nr_orig);
5314 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5315 &stripe_index);
5316 if (!(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)))
5317 mirror_num = 1;
5318 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
5319 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
5320 num_stripes = map->num_stripes;
5321 else if (mirror_num)
5322 stripe_index = mirror_num - 1;
5323 else {
5324 stripe_index = find_live_mirror(fs_info, map, 0,
5325 map->num_stripes,
5326 current->pid % map->num_stripes,
5327 dev_replace_is_ongoing);
5328 mirror_num = stripe_index + 1;
5329 }
5330
5331 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
5332 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
5333 num_stripes = map->num_stripes;
5334 } else if (mirror_num) {
5335 stripe_index = mirror_num - 1;
5336 } else {
5337 mirror_num = 1;
5338 }
5339
5340 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5341 u32 factor = map->num_stripes / map->sub_stripes;
5342
5343 stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
5344 stripe_index *= map->sub_stripes;
5345
5346 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5347 num_stripes = map->sub_stripes;
5348 else if (rw & REQ_DISCARD)
5349 num_stripes = min_t(u64, map->sub_stripes *
5350 (stripe_nr_end - stripe_nr_orig),
5351 map->num_stripes);
5352 else if (mirror_num)
5353 stripe_index += mirror_num - 1;
5354 else {
5355 int old_stripe_index = stripe_index;
5356 stripe_index = find_live_mirror(fs_info, map,
5357 stripe_index,
5358 map->sub_stripes, stripe_index +
5359 current->pid % map->sub_stripes,
5360 dev_replace_is_ongoing);
5361 mirror_num = stripe_index - old_stripe_index + 1;
5362 }
5363
5364 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5365 if (need_raid_map &&
5366 ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5367 mirror_num > 1)) {
5368 /* push stripe_nr back to the start of the full stripe */
5369 stripe_nr = div_u64(raid56_full_stripe_start,
5370 stripe_len * nr_data_stripes(map));
5371
5372 /* RAID[56] write or recovery. Return all stripes */
5373 num_stripes = map->num_stripes;
5374 max_errors = nr_parity_stripes(map);
5375
5376 *length = map->stripe_len;
5377 stripe_index = 0;
5378 stripe_offset = 0;
5379 } else {
5380 /*
5381 * Mirror #0 or #1 means the original data block.
5382 * Mirror #2 is RAID5 parity block.
5383 * Mirror #3 is RAID6 Q block.
5384 */
5385 stripe_nr = div_u64_rem(stripe_nr,
5386 nr_data_stripes(map), &stripe_index);
5387 if (mirror_num > 1)
5388 stripe_index = nr_data_stripes(map) +
5389 mirror_num - 2;
5390
5391 /* We distribute the parity blocks across stripes */
5392 div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
5393 &stripe_index);
5394 if (!(rw & (REQ_WRITE | REQ_DISCARD |
5395 REQ_GET_READ_MIRRORS)) && mirror_num <= 1)
5396 mirror_num = 1;
5397 }
5398 } else {
5399 /*
5400 * after this, stripe_nr is the number of stripes on this
5401 * device we have to walk to find the data, and stripe_index is
5402 * the number of our device in the stripe array
5403 */
5404 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5405 &stripe_index);
5406 mirror_num = stripe_index + 1;
5407 }
5408 BUG_ON(stripe_index >= map->num_stripes);
5409
5410 num_alloc_stripes = num_stripes;
5411 if (dev_replace_is_ongoing) {
5412 if (rw & (REQ_WRITE | REQ_DISCARD))
5413 num_alloc_stripes <<= 1;
5414 if (rw & REQ_GET_READ_MIRRORS)
5415 num_alloc_stripes++;
5416 tgtdev_indexes = num_stripes;
5417 }
5418
5419 bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes);
5420 if (!bbio) {
5421 ret = -ENOMEM;
5422 goto out;
5423 }
5424 if (dev_replace_is_ongoing)
5425 bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes);
5426
5427 /* build raid_map */
5428 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
5429 need_raid_map && ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5430 mirror_num > 1)) {
5431 u64 tmp;
5432 unsigned rot;
5433
5434 bbio->raid_map = (u64 *)((void *)bbio->stripes +
5435 sizeof(struct btrfs_bio_stripe) *
5436 num_alloc_stripes +
5437 sizeof(int) * tgtdev_indexes);
5438
5439 /* Work out the disk rotation on this stripe-set */
5440 div_u64_rem(stripe_nr, num_stripes, &rot);
5441
5442 /* Fill in the logical address of each stripe */
5443 tmp = stripe_nr * nr_data_stripes(map);
5444 for (i = 0; i < nr_data_stripes(map); i++)
5445 bbio->raid_map[(i+rot) % num_stripes] =
5446 em->start + (tmp + i) * map->stripe_len;
5447
5448 bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
5449 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5450 bbio->raid_map[(i+rot+1) % num_stripes] =
5451 RAID6_Q_STRIPE;
5452 }
5453
5454 if (rw & REQ_DISCARD) {
5455 u32 factor = 0;
5456 u32 sub_stripes = 0;
5457 u64 stripes_per_dev = 0;
5458 u32 remaining_stripes = 0;
5459 u32 last_stripe = 0;
5460
5461 if (map->type &
5462 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
5463 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5464 sub_stripes = 1;
5465 else
5466 sub_stripes = map->sub_stripes;
5467
5468 factor = map->num_stripes / sub_stripes;
5469 stripes_per_dev = div_u64_rem(stripe_nr_end -
5470 stripe_nr_orig,
5471 factor,
5472 &remaining_stripes);
5473 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
5474 last_stripe *= sub_stripes;
5475 }
5476
5477 for (i = 0; i < num_stripes; i++) {
5478 bbio->stripes[i].physical =
5479 map->stripes[stripe_index].physical +
5480 stripe_offset + stripe_nr * map->stripe_len;
5481 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
5482
5483 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
5484 BTRFS_BLOCK_GROUP_RAID10)) {
5485 bbio->stripes[i].length = stripes_per_dev *
5486 map->stripe_len;
5487
5488 if (i / sub_stripes < remaining_stripes)
5489 bbio->stripes[i].length +=
5490 map->stripe_len;
5491
5492 /*
5493 * Special for the first stripe and
5494 * the last stripe:
5495 *
5496 * |-------|...|-------|
5497 * |----------|
5498 * off end_off
5499 */
5500 if (i < sub_stripes)
5501 bbio->stripes[i].length -=
5502 stripe_offset;
5503
5504 if (stripe_index >= last_stripe &&
5505 stripe_index <= (last_stripe +
5506 sub_stripes - 1))
5507 bbio->stripes[i].length -=
5508 stripe_end_offset;
5509
5510 if (i == sub_stripes - 1)
5511 stripe_offset = 0;
5512 } else
5513 bbio->stripes[i].length = *length;
5514
5515 stripe_index++;
5516 if (stripe_index == map->num_stripes) {
5517 /* This could only happen for RAID0/10 */
5518 stripe_index = 0;
5519 stripe_nr++;
5520 }
5521 }
5522 } else {
5523 for (i = 0; i < num_stripes; i++) {
5524 bbio->stripes[i].physical =
5525 map->stripes[stripe_index].physical +
5526 stripe_offset +
5527 stripe_nr * map->stripe_len;
5528 bbio->stripes[i].dev =
5529 map->stripes[stripe_index].dev;
5530 stripe_index++;
5531 }
5532 }
5533
5534 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5535 max_errors = btrfs_chunk_max_errors(map);
5536
5537 if (bbio->raid_map)
5538 sort_parity_stripes(bbio, num_stripes);
5539
5540 tgtdev_indexes = 0;
5541 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
5542 dev_replace->tgtdev != NULL) {
5543 int index_where_to_add;
5544 u64 srcdev_devid = dev_replace->srcdev->devid;
5545
5546 /*
5547 * duplicate the write operations while the dev replace
5548 * procedure is running. Since the copying of the old disk
5549 * to the new disk takes place at run time while the
5550 * filesystem is mounted writable, the regular write
5551 * operations to the old disk have to be duplicated to go
5552 * to the new disk as well.
5553 * Note that device->missing is handled by the caller, and
5554 * that the write to the old disk is already set up in the
5555 * stripes array.
5556 */
5557 index_where_to_add = num_stripes;
5558 for (i = 0; i < num_stripes; i++) {
5559 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5560 /* write to new disk, too */
5561 struct btrfs_bio_stripe *new =
5562 bbio->stripes + index_where_to_add;
5563 struct btrfs_bio_stripe *old =
5564 bbio->stripes + i;
5565
5566 new->physical = old->physical;
5567 new->length = old->length;
5568 new->dev = dev_replace->tgtdev;
5569 bbio->tgtdev_map[i] = index_where_to_add;
5570 index_where_to_add++;
5571 max_errors++;
5572 tgtdev_indexes++;
5573 }
5574 }
5575 num_stripes = index_where_to_add;
5576 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
5577 dev_replace->tgtdev != NULL) {
5578 u64 srcdev_devid = dev_replace->srcdev->devid;
5579 int index_srcdev = 0;
5580 int found = 0;
5581 u64 physical_of_found = 0;
5582
5583 /*
5584 * During the dev-replace procedure, the target drive can
5585 * also be used to read data in case it is needed to repair
5586 * a corrupt block elsewhere. This is possible if the
5587 * requested area is left of the left cursor. In this area,
5588 * the target drive is a full copy of the source drive.
5589 */
5590 for (i = 0; i < num_stripes; i++) {
5591 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5592 /*
5593 * In case of DUP, in order to keep it
5594 * simple, only add the mirror with the
5595 * lowest physical address
5596 */
5597 if (found &&
5598 physical_of_found <=
5599 bbio->stripes[i].physical)
5600 continue;
5601 index_srcdev = i;
5602 found = 1;
5603 physical_of_found = bbio->stripes[i].physical;
5604 }
5605 }
5606 if (found) {
5607 if (physical_of_found + map->stripe_len <=
5608 dev_replace->cursor_left) {
5609 struct btrfs_bio_stripe *tgtdev_stripe =
5610 bbio->stripes + num_stripes;
5611
5612 tgtdev_stripe->physical = physical_of_found;
5613 tgtdev_stripe->length =
5614 bbio->stripes[index_srcdev].length;
5615 tgtdev_stripe->dev = dev_replace->tgtdev;
5616 bbio->tgtdev_map[index_srcdev] = num_stripes;
5617
5618 tgtdev_indexes++;
5619 num_stripes++;
5620 }
5621 }
5622 }
5623
5624 *bbio_ret = bbio;
5625 bbio->map_type = map->type;
5626 bbio->num_stripes = num_stripes;
5627 bbio->max_errors = max_errors;
5628 bbio->mirror_num = mirror_num;
5629 bbio->num_tgtdevs = tgtdev_indexes;
5630
5631 /*
5632 * this is the case that REQ_READ && dev_replace_is_ongoing &&
5633 * mirror_num == num_stripes + 1 && dev_replace target drive is
5634 * available as a mirror
5635 */
5636 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
5637 WARN_ON(num_stripes > 1);
5638 bbio->stripes[0].dev = dev_replace->tgtdev;
5639 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
5640 bbio->mirror_num = map->num_stripes + 1;
5641 }
5642 out:
5643 if (dev_replace_is_ongoing)
5644 btrfs_dev_replace_unlock(dev_replace);
5645 free_extent_map(em);
5646 return ret;
5647 }
5648
5649 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5650 u64 logical, u64 *length,
5651 struct btrfs_bio **bbio_ret, int mirror_num)
5652 {
5653 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5654 mirror_num, 0);
5655 }
5656
5657 /* For Scrub/replace */
5658 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
5659 u64 logical, u64 *length,
5660 struct btrfs_bio **bbio_ret, int mirror_num,
5661 int need_raid_map)
5662 {
5663 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5664 mirror_num, need_raid_map);
5665 }
5666
5667 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
5668 u64 chunk_start, u64 physical, u64 devid,
5669 u64 **logical, int *naddrs, int *stripe_len)
5670 {
5671 struct extent_map_tree *em_tree = &map_tree->map_tree;
5672 struct extent_map *em;
5673 struct map_lookup *map;
5674 u64 *buf;
5675 u64 bytenr;
5676 u64 length;
5677 u64 stripe_nr;
5678 u64 rmap_len;
5679 int i, j, nr = 0;
5680
5681 read_lock(&em_tree->lock);
5682 em = lookup_extent_mapping(em_tree, chunk_start, 1);
5683 read_unlock(&em_tree->lock);
5684
5685 if (!em) {
5686 printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
5687 chunk_start);
5688 return -EIO;
5689 }
5690
5691 if (em->start != chunk_start) {
5692 printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
5693 em->start, chunk_start);
5694 free_extent_map(em);
5695 return -EIO;
5696 }
5697 map = (struct map_lookup *)em->bdev;
5698
5699 length = em->len;
5700 rmap_len = map->stripe_len;
5701
5702 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5703 length = div_u64(length, map->num_stripes / map->sub_stripes);
5704 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5705 length = div_u64(length, map->num_stripes);
5706 else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5707 length = div_u64(length, nr_data_stripes(map));
5708 rmap_len = map->stripe_len * nr_data_stripes(map);
5709 }
5710
5711 buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
5712 BUG_ON(!buf); /* -ENOMEM */
5713
5714 for (i = 0; i < map->num_stripes; i++) {
5715 if (devid && map->stripes[i].dev->devid != devid)
5716 continue;
5717 if (map->stripes[i].physical > physical ||
5718 map->stripes[i].physical + length <= physical)
5719 continue;
5720
5721 stripe_nr = physical - map->stripes[i].physical;
5722 stripe_nr = div_u64(stripe_nr, map->stripe_len);
5723
5724 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5725 stripe_nr = stripe_nr * map->num_stripes + i;
5726 stripe_nr = div_u64(stripe_nr, map->sub_stripes);
5727 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5728 stripe_nr = stripe_nr * map->num_stripes + i;
5729 } /* else if RAID[56], multiply by nr_data_stripes().
5730 * Alternatively, just use rmap_len below instead of
5731 * map->stripe_len */
5732
5733 bytenr = chunk_start + stripe_nr * rmap_len;
5734 WARN_ON(nr >= map->num_stripes);
5735 for (j = 0; j < nr; j++) {
5736 if (buf[j] == bytenr)
5737 break;
5738 }
5739 if (j == nr) {
5740 WARN_ON(nr >= map->num_stripes);
5741 buf[nr++] = bytenr;
5742 }
5743 }
5744
5745 *logical = buf;
5746 *naddrs = nr;
5747 *stripe_len = rmap_len;
5748
5749 free_extent_map(em);
5750 return 0;
5751 }
5752
5753 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio)
5754 {
5755 bio->bi_private = bbio->private;
5756 bio->bi_end_io = bbio->end_io;
5757 bio_endio(bio);
5758
5759 btrfs_put_bbio(bbio);
5760 }
5761
5762 static void btrfs_end_bio(struct bio *bio)
5763 {
5764 struct btrfs_bio *bbio = bio->bi_private;
5765 int is_orig_bio = 0;
5766
5767 if (bio->bi_error) {
5768 atomic_inc(&bbio->error);
5769 if (bio->bi_error == -EIO || bio->bi_error == -EREMOTEIO) {
5770 unsigned int stripe_index =
5771 btrfs_io_bio(bio)->stripe_index;
5772 struct btrfs_device *dev;
5773
5774 BUG_ON(stripe_index >= bbio->num_stripes);
5775 dev = bbio->stripes[stripe_index].dev;
5776 if (dev->bdev) {
5777 if (bio->bi_rw & WRITE)
5778 btrfs_dev_stat_inc(dev,
5779 BTRFS_DEV_STAT_WRITE_ERRS);
5780 else
5781 btrfs_dev_stat_inc(dev,
5782 BTRFS_DEV_STAT_READ_ERRS);
5783 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
5784 btrfs_dev_stat_inc(dev,
5785 BTRFS_DEV_STAT_FLUSH_ERRS);
5786 btrfs_dev_stat_print_on_error(dev);
5787 }
5788 }
5789 }
5790
5791 if (bio == bbio->orig_bio)
5792 is_orig_bio = 1;
5793
5794 btrfs_bio_counter_dec(bbio->fs_info);
5795
5796 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5797 if (!is_orig_bio) {
5798 bio_put(bio);
5799 bio = bbio->orig_bio;
5800 }
5801
5802 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5803 /* only send an error to the higher layers if it is
5804 * beyond the tolerance of the btrfs bio
5805 */
5806 if (atomic_read(&bbio->error) > bbio->max_errors) {
5807 bio->bi_error = -EIO;
5808 } else {
5809 /*
5810 * this bio is actually up to date, we didn't
5811 * go over the max number of errors
5812 */
5813 bio->bi_error = 0;
5814 }
5815
5816 btrfs_end_bbio(bbio, bio);
5817 } else if (!is_orig_bio) {
5818 bio_put(bio);
5819 }
5820 }
5821
5822 /*
5823 * see run_scheduled_bios for a description of why bios are collected for
5824 * async submit.
5825 *
5826 * This will add one bio to the pending list for a device and make sure
5827 * the work struct is scheduled.
5828 */
5829 static noinline void btrfs_schedule_bio(struct btrfs_root *root,
5830 struct btrfs_device *device,
5831 int rw, struct bio *bio)
5832 {
5833 int should_queue = 1;
5834 struct btrfs_pending_bios *pending_bios;
5835
5836 if (device->missing || !device->bdev) {
5837 bio_io_error(bio);
5838 return;
5839 }
5840
5841 /* don't bother with additional async steps for reads, right now */
5842 if (!(rw & REQ_WRITE)) {
5843 bio_get(bio);
5844 btrfsic_submit_bio(rw, bio);
5845 bio_put(bio);
5846 return;
5847 }
5848
5849 /*
5850 * nr_async_bios allows us to reliably return congestion to the
5851 * higher layers. Otherwise, the async bio makes it appear we have
5852 * made progress against dirty pages when we've really just put it
5853 * on a queue for later
5854 */
5855 atomic_inc(&root->fs_info->nr_async_bios);
5856 WARN_ON(bio->bi_next);
5857 bio->bi_next = NULL;
5858 bio->bi_rw |= rw;
5859
5860 spin_lock(&device->io_lock);
5861 if (bio->bi_rw & REQ_SYNC)
5862 pending_bios = &device->pending_sync_bios;
5863 else
5864 pending_bios = &device->pending_bios;
5865
5866 if (pending_bios->tail)
5867 pending_bios->tail->bi_next = bio;
5868
5869 pending_bios->tail = bio;
5870 if (!pending_bios->head)
5871 pending_bios->head = bio;
5872 if (device->running_pending)
5873 should_queue = 0;
5874
5875 spin_unlock(&device->io_lock);
5876
5877 if (should_queue)
5878 btrfs_queue_work(root->fs_info->submit_workers,
5879 &device->work);
5880 }
5881
5882 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5883 struct bio *bio, u64 physical, int dev_nr,
5884 int rw, int async)
5885 {
5886 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
5887
5888 bio->bi_private = bbio;
5889 btrfs_io_bio(bio)->stripe_index = dev_nr;
5890 bio->bi_end_io = btrfs_end_bio;
5891 bio->bi_iter.bi_sector = physical >> 9;
5892 #ifdef DEBUG
5893 {
5894 struct rcu_string *name;
5895
5896 rcu_read_lock();
5897 name = rcu_dereference(dev->name);
5898 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
5899 "(%s id %llu), size=%u\n", rw,
5900 (u64)bio->bi_iter.bi_sector, (u_long)dev->bdev->bd_dev,
5901 name->str, dev->devid, bio->bi_iter.bi_size);
5902 rcu_read_unlock();
5903 }
5904 #endif
5905 bio->bi_bdev = dev->bdev;
5906
5907 btrfs_bio_counter_inc_noblocked(root->fs_info);
5908
5909 if (async)
5910 btrfs_schedule_bio(root, dev, rw, bio);
5911 else
5912 btrfsic_submit_bio(rw, bio);
5913 }
5914
5915 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
5916 {
5917 atomic_inc(&bbio->error);
5918 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5919 /* Shoud be the original bio. */
5920 WARN_ON(bio != bbio->orig_bio);
5921
5922 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5923 bio->bi_iter.bi_sector = logical >> 9;
5924 bio->bi_error = -EIO;
5925 btrfs_end_bbio(bbio, bio);
5926 }
5927 }
5928
5929 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
5930 int mirror_num, int async_submit)
5931 {
5932 struct btrfs_device *dev;
5933 struct bio *first_bio = bio;
5934 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
5935 u64 length = 0;
5936 u64 map_length;
5937 int ret;
5938 int dev_nr;
5939 int total_devs;
5940 struct btrfs_bio *bbio = NULL;
5941
5942 length = bio->bi_iter.bi_size;
5943 map_length = length;
5944
5945 btrfs_bio_counter_inc_blocked(root->fs_info);
5946 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
5947 mirror_num, 1);
5948 if (ret) {
5949 btrfs_bio_counter_dec(root->fs_info);
5950 return ret;
5951 }
5952
5953 total_devs = bbio->num_stripes;
5954 bbio->orig_bio = first_bio;
5955 bbio->private = first_bio->bi_private;
5956 bbio->end_io = first_bio->bi_end_io;
5957 bbio->fs_info = root->fs_info;
5958 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
5959
5960 if (bbio->raid_map) {
5961 /* In this case, map_length has been set to the length of
5962 a single stripe; not the whole write */
5963 if (rw & WRITE) {
5964 ret = raid56_parity_write(root, bio, bbio, map_length);
5965 } else {
5966 ret = raid56_parity_recover(root, bio, bbio, map_length,
5967 mirror_num, 1);
5968 }
5969
5970 btrfs_bio_counter_dec(root->fs_info);
5971 return ret;
5972 }
5973
5974 if (map_length < length) {
5975 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
5976 logical, length, map_length);
5977 BUG();
5978 }
5979
5980 for (dev_nr = 0; dev_nr < total_devs; dev_nr++) {
5981 dev = bbio->stripes[dev_nr].dev;
5982 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
5983 bbio_error(bbio, first_bio, logical);
5984 continue;
5985 }
5986
5987 if (dev_nr < total_devs - 1) {
5988 bio = btrfs_bio_clone(first_bio, GFP_NOFS);
5989 BUG_ON(!bio); /* -ENOMEM */
5990 } else
5991 bio = first_bio;
5992
5993 submit_stripe_bio(root, bbio, bio,
5994 bbio->stripes[dev_nr].physical, dev_nr, rw,
5995 async_submit);
5996 }
5997 btrfs_bio_counter_dec(root->fs_info);
5998 return 0;
5999 }
6000
6001 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
6002 u8 *uuid, u8 *fsid)
6003 {
6004 struct btrfs_device *device;
6005 struct btrfs_fs_devices *cur_devices;
6006
6007 cur_devices = fs_info->fs_devices;
6008 while (cur_devices) {
6009 if (!fsid ||
6010 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
6011 device = __find_device(&cur_devices->devices,
6012 devid, uuid);
6013 if (device)
6014 return device;
6015 }
6016 cur_devices = cur_devices->seed;
6017 }
6018 return NULL;
6019 }
6020
6021 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
6022 struct btrfs_fs_devices *fs_devices,
6023 u64 devid, u8 *dev_uuid)
6024 {
6025 struct btrfs_device *device;
6026
6027 device = btrfs_alloc_device(NULL, &devid, dev_uuid);
6028 if (IS_ERR(device))
6029 return NULL;
6030
6031 list_add(&device->dev_list, &fs_devices->devices);
6032 device->fs_devices = fs_devices;
6033 fs_devices->num_devices++;
6034
6035 device->missing = 1;
6036 fs_devices->missing_devices++;
6037
6038 return device;
6039 }
6040
6041 /**
6042 * btrfs_alloc_device - allocate struct btrfs_device
6043 * @fs_info: used only for generating a new devid, can be NULL if
6044 * devid is provided (i.e. @devid != NULL).
6045 * @devid: a pointer to devid for this device. If NULL a new devid
6046 * is generated.
6047 * @uuid: a pointer to UUID for this device. If NULL a new UUID
6048 * is generated.
6049 *
6050 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
6051 * on error. Returned struct is not linked onto any lists and can be
6052 * destroyed with kfree() right away.
6053 */
6054 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
6055 const u64 *devid,
6056 const u8 *uuid)
6057 {
6058 struct btrfs_device *dev;
6059 u64 tmp;
6060
6061 if (WARN_ON(!devid && !fs_info))
6062 return ERR_PTR(-EINVAL);
6063
6064 dev = __alloc_device();
6065 if (IS_ERR(dev))
6066 return dev;
6067
6068 if (devid)
6069 tmp = *devid;
6070 else {
6071 int ret;
6072
6073 ret = find_next_devid(fs_info, &tmp);
6074 if (ret) {
6075 kfree(dev);
6076 return ERR_PTR(ret);
6077 }
6078 }
6079 dev->devid = tmp;
6080
6081 if (uuid)
6082 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
6083 else
6084 generate_random_uuid(dev->uuid);
6085
6086 btrfs_init_work(&dev->work, btrfs_submit_helper,
6087 pending_bios_fn, NULL, NULL);
6088
6089 return dev;
6090 }
6091
6092 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
6093 struct extent_buffer *leaf,
6094 struct btrfs_chunk *chunk)
6095 {
6096 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
6097 struct map_lookup *map;
6098 struct extent_map *em;
6099 u64 logical;
6100 u64 length;
6101 u64 devid;
6102 u8 uuid[BTRFS_UUID_SIZE];
6103 int num_stripes;
6104 int ret;
6105 int i;
6106
6107 logical = key->offset;
6108 length = btrfs_chunk_length(leaf, chunk);
6109
6110 read_lock(&map_tree->map_tree.lock);
6111 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
6112 read_unlock(&map_tree->map_tree.lock);
6113
6114 /* already mapped? */
6115 if (em && em->start <= logical && em->start + em->len > logical) {
6116 free_extent_map(em);
6117 return 0;
6118 } else if (em) {
6119 free_extent_map(em);
6120 }
6121
6122 em = alloc_extent_map();
6123 if (!em)
6124 return -ENOMEM;
6125 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
6126 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
6127 if (!map) {
6128 free_extent_map(em);
6129 return -ENOMEM;
6130 }
6131
6132 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
6133 em->bdev = (struct block_device *)map;
6134 em->start = logical;
6135 em->len = length;
6136 em->orig_start = 0;
6137 em->block_start = 0;
6138 em->block_len = em->len;
6139
6140 map->num_stripes = num_stripes;
6141 map->io_width = btrfs_chunk_io_width(leaf, chunk);
6142 map->io_align = btrfs_chunk_io_align(leaf, chunk);
6143 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
6144 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6145 map->type = btrfs_chunk_type(leaf, chunk);
6146 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
6147 for (i = 0; i < num_stripes; i++) {
6148 map->stripes[i].physical =
6149 btrfs_stripe_offset_nr(leaf, chunk, i);
6150 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
6151 read_extent_buffer(leaf, uuid, (unsigned long)
6152 btrfs_stripe_dev_uuid_nr(chunk, i),
6153 BTRFS_UUID_SIZE);
6154 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
6155 uuid, NULL);
6156 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
6157 free_extent_map(em);
6158 return -EIO;
6159 }
6160 if (!map->stripes[i].dev) {
6161 map->stripes[i].dev =
6162 add_missing_dev(root, root->fs_info->fs_devices,
6163 devid, uuid);
6164 if (!map->stripes[i].dev) {
6165 free_extent_map(em);
6166 return -EIO;
6167 }
6168 btrfs_warn(root->fs_info, "devid %llu uuid %pU is missing",
6169 devid, uuid);
6170 }
6171 map->stripes[i].dev->in_fs_metadata = 1;
6172 }
6173
6174 write_lock(&map_tree->map_tree.lock);
6175 ret = add_extent_mapping(&map_tree->map_tree, em, 0);
6176 write_unlock(&map_tree->map_tree.lock);
6177 BUG_ON(ret); /* Tree corruption */
6178 free_extent_map(em);
6179
6180 return 0;
6181 }
6182
6183 static void fill_device_from_item(struct extent_buffer *leaf,
6184 struct btrfs_dev_item *dev_item,
6185 struct btrfs_device *device)
6186 {
6187 unsigned long ptr;
6188
6189 device->devid = btrfs_device_id(leaf, dev_item);
6190 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
6191 device->total_bytes = device->disk_total_bytes;
6192 device->commit_total_bytes = device->disk_total_bytes;
6193 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
6194 device->commit_bytes_used = device->bytes_used;
6195 device->type = btrfs_device_type(leaf, dev_item);
6196 device->io_align = btrfs_device_io_align(leaf, dev_item);
6197 device->io_width = btrfs_device_io_width(leaf, dev_item);
6198 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
6199 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
6200 device->is_tgtdev_for_dev_replace = 0;
6201
6202 ptr = btrfs_device_uuid(dev_item);
6203 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
6204 }
6205
6206 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_root *root,
6207 u8 *fsid)
6208 {
6209 struct btrfs_fs_devices *fs_devices;
6210 int ret;
6211
6212 BUG_ON(!mutex_is_locked(&uuid_mutex));
6213
6214 fs_devices = root->fs_info->fs_devices->seed;
6215 while (fs_devices) {
6216 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE))
6217 return fs_devices;
6218
6219 fs_devices = fs_devices->seed;
6220 }
6221
6222 fs_devices = find_fsid(fsid);
6223 if (!fs_devices) {
6224 if (!btrfs_test_opt(root, DEGRADED))
6225 return ERR_PTR(-ENOENT);
6226
6227 fs_devices = alloc_fs_devices(fsid);
6228 if (IS_ERR(fs_devices))
6229 return fs_devices;
6230
6231 fs_devices->seeding = 1;
6232 fs_devices->opened = 1;
6233 return fs_devices;
6234 }
6235
6236 fs_devices = clone_fs_devices(fs_devices);
6237 if (IS_ERR(fs_devices))
6238 return fs_devices;
6239
6240 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
6241 root->fs_info->bdev_holder);
6242 if (ret) {
6243 free_fs_devices(fs_devices);
6244 fs_devices = ERR_PTR(ret);
6245 goto out;
6246 }
6247
6248 if (!fs_devices->seeding) {
6249 __btrfs_close_devices(fs_devices);
6250 free_fs_devices(fs_devices);
6251 fs_devices = ERR_PTR(-EINVAL);
6252 goto out;
6253 }
6254
6255 fs_devices->seed = root->fs_info->fs_devices->seed;
6256 root->fs_info->fs_devices->seed = fs_devices;
6257 out:
6258 return fs_devices;
6259 }
6260
6261 static int read_one_dev(struct btrfs_root *root,
6262 struct extent_buffer *leaf,
6263 struct btrfs_dev_item *dev_item)
6264 {
6265 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6266 struct btrfs_device *device;
6267 u64 devid;
6268 int ret;
6269 u8 fs_uuid[BTRFS_UUID_SIZE];
6270 u8 dev_uuid[BTRFS_UUID_SIZE];
6271
6272 devid = btrfs_device_id(leaf, dev_item);
6273 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
6274 BTRFS_UUID_SIZE);
6275 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
6276 BTRFS_UUID_SIZE);
6277
6278 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
6279 fs_devices = open_seed_devices(root, fs_uuid);
6280 if (IS_ERR(fs_devices))
6281 return PTR_ERR(fs_devices);
6282 }
6283
6284 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
6285 if (!device) {
6286 if (!btrfs_test_opt(root, DEGRADED))
6287 return -EIO;
6288
6289 device = add_missing_dev(root, fs_devices, devid, dev_uuid);
6290 if (!device)
6291 return -ENOMEM;
6292 btrfs_warn(root->fs_info, "devid %llu uuid %pU missing",
6293 devid, dev_uuid);
6294 } else {
6295 if (!device->bdev && !btrfs_test_opt(root, DEGRADED))
6296 return -EIO;
6297
6298 if(!device->bdev && !device->missing) {
6299 /*
6300 * this happens when a device that was properly setup
6301 * in the device info lists suddenly goes bad.
6302 * device->bdev is NULL, and so we have to set
6303 * device->missing to one here
6304 */
6305 device->fs_devices->missing_devices++;
6306 device->missing = 1;
6307 }
6308
6309 /* Move the device to its own fs_devices */
6310 if (device->fs_devices != fs_devices) {
6311 ASSERT(device->missing);
6312
6313 list_move(&device->dev_list, &fs_devices->devices);
6314 device->fs_devices->num_devices--;
6315 fs_devices->num_devices++;
6316
6317 device->fs_devices->missing_devices--;
6318 fs_devices->missing_devices++;
6319
6320 device->fs_devices = fs_devices;
6321 }
6322 }
6323
6324 if (device->fs_devices != root->fs_info->fs_devices) {
6325 BUG_ON(device->writeable);
6326 if (device->generation !=
6327 btrfs_device_generation(leaf, dev_item))
6328 return -EINVAL;
6329 }
6330
6331 fill_device_from_item(leaf, dev_item, device);
6332 device->in_fs_metadata = 1;
6333 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
6334 device->fs_devices->total_rw_bytes += device->total_bytes;
6335 spin_lock(&root->fs_info->free_chunk_lock);
6336 root->fs_info->free_chunk_space += device->total_bytes -
6337 device->bytes_used;
6338 spin_unlock(&root->fs_info->free_chunk_lock);
6339 }
6340 ret = 0;
6341 return ret;
6342 }
6343
6344 int btrfs_read_sys_array(struct btrfs_root *root)
6345 {
6346 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
6347 struct extent_buffer *sb;
6348 struct btrfs_disk_key *disk_key;
6349 struct btrfs_chunk *chunk;
6350 u8 *array_ptr;
6351 unsigned long sb_array_offset;
6352 int ret = 0;
6353 u32 num_stripes;
6354 u32 array_size;
6355 u32 len = 0;
6356 u32 cur_offset;
6357 struct btrfs_key key;
6358
6359 ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
6360 /*
6361 * This will create extent buffer of nodesize, superblock size is
6362 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
6363 * overallocate but we can keep it as-is, only the first page is used.
6364 */
6365 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
6366 if (!sb)
6367 return -ENOMEM;
6368 btrfs_set_buffer_uptodate(sb);
6369 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
6370 /*
6371 * The sb extent buffer is artifical and just used to read the system array.
6372 * btrfs_set_buffer_uptodate() call does not properly mark all it's
6373 * pages up-to-date when the page is larger: extent does not cover the
6374 * whole page and consequently check_page_uptodate does not find all
6375 * the page's extents up-to-date (the hole beyond sb),
6376 * write_extent_buffer then triggers a WARN_ON.
6377 *
6378 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
6379 * but sb spans only this function. Add an explicit SetPageUptodate call
6380 * to silence the warning eg. on PowerPC 64.
6381 */
6382 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
6383 SetPageUptodate(sb->pages[0]);
6384
6385 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
6386 array_size = btrfs_super_sys_array_size(super_copy);
6387
6388 array_ptr = super_copy->sys_chunk_array;
6389 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
6390 cur_offset = 0;
6391
6392 while (cur_offset < array_size) {
6393 disk_key = (struct btrfs_disk_key *)array_ptr;
6394 len = sizeof(*disk_key);
6395 if (cur_offset + len > array_size)
6396 goto out_short_read;
6397
6398 btrfs_disk_key_to_cpu(&key, disk_key);
6399
6400 array_ptr += len;
6401 sb_array_offset += len;
6402 cur_offset += len;
6403
6404 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6405 chunk = (struct btrfs_chunk *)sb_array_offset;
6406 /*
6407 * At least one btrfs_chunk with one stripe must be
6408 * present, exact stripe count check comes afterwards
6409 */
6410 len = btrfs_chunk_item_size(1);
6411 if (cur_offset + len > array_size)
6412 goto out_short_read;
6413
6414 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
6415 len = btrfs_chunk_item_size(num_stripes);
6416 if (cur_offset + len > array_size)
6417 goto out_short_read;
6418
6419 ret = read_one_chunk(root, &key, sb, chunk);
6420 if (ret)
6421 break;
6422 } else {
6423 ret = -EIO;
6424 break;
6425 }
6426 array_ptr += len;
6427 sb_array_offset += len;
6428 cur_offset += len;
6429 }
6430 free_extent_buffer(sb);
6431 return ret;
6432
6433 out_short_read:
6434 printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
6435 len, cur_offset);
6436 free_extent_buffer(sb);
6437 return -EIO;
6438 }
6439
6440 int btrfs_read_chunk_tree(struct btrfs_root *root)
6441 {
6442 struct btrfs_path *path;
6443 struct extent_buffer *leaf;
6444 struct btrfs_key key;
6445 struct btrfs_key found_key;
6446 int ret;
6447 int slot;
6448
6449 root = root->fs_info->chunk_root;
6450
6451 path = btrfs_alloc_path();
6452 if (!path)
6453 return -ENOMEM;
6454
6455 mutex_lock(&uuid_mutex);
6456 lock_chunks(root);
6457
6458 /*
6459 * Read all device items, and then all the chunk items. All
6460 * device items are found before any chunk item (their object id
6461 * is smaller than the lowest possible object id for a chunk
6462 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
6463 */
6464 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
6465 key.offset = 0;
6466 key.type = 0;
6467 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6468 if (ret < 0)
6469 goto error;
6470 while (1) {
6471 leaf = path->nodes[0];
6472 slot = path->slots[0];
6473 if (slot >= btrfs_header_nritems(leaf)) {
6474 ret = btrfs_next_leaf(root, path);
6475 if (ret == 0)
6476 continue;
6477 if (ret < 0)
6478 goto error;
6479 break;
6480 }
6481 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6482 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
6483 struct btrfs_dev_item *dev_item;
6484 dev_item = btrfs_item_ptr(leaf, slot,
6485 struct btrfs_dev_item);
6486 ret = read_one_dev(root, leaf, dev_item);
6487 if (ret)
6488 goto error;
6489 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
6490 struct btrfs_chunk *chunk;
6491 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
6492 ret = read_one_chunk(root, &found_key, leaf, chunk);
6493 if (ret)
6494 goto error;
6495 }
6496 path->slots[0]++;
6497 }
6498 ret = 0;
6499 error:
6500 unlock_chunks(root);
6501 mutex_unlock(&uuid_mutex);
6502
6503 btrfs_free_path(path);
6504 return ret;
6505 }
6506
6507 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
6508 {
6509 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6510 struct btrfs_device *device;
6511
6512 while (fs_devices) {
6513 mutex_lock(&fs_devices->device_list_mutex);
6514 list_for_each_entry(device, &fs_devices->devices, dev_list)
6515 device->dev_root = fs_info->dev_root;
6516 mutex_unlock(&fs_devices->device_list_mutex);
6517
6518 fs_devices = fs_devices->seed;
6519 }
6520 }
6521
6522 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
6523 {
6524 int i;
6525
6526 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6527 btrfs_dev_stat_reset(dev, i);
6528 }
6529
6530 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
6531 {
6532 struct btrfs_key key;
6533 struct btrfs_key found_key;
6534 struct btrfs_root *dev_root = fs_info->dev_root;
6535 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6536 struct extent_buffer *eb;
6537 int slot;
6538 int ret = 0;
6539 struct btrfs_device *device;
6540 struct btrfs_path *path = NULL;
6541 int i;
6542
6543 path = btrfs_alloc_path();
6544 if (!path) {
6545 ret = -ENOMEM;
6546 goto out;
6547 }
6548
6549 mutex_lock(&fs_devices->device_list_mutex);
6550 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6551 int item_size;
6552 struct btrfs_dev_stats_item *ptr;
6553
6554 key.objectid = 0;
6555 key.type = BTRFS_DEV_STATS_KEY;
6556 key.offset = device->devid;
6557 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
6558 if (ret) {
6559 __btrfs_reset_dev_stats(device);
6560 device->dev_stats_valid = 1;
6561 btrfs_release_path(path);
6562 continue;
6563 }
6564 slot = path->slots[0];
6565 eb = path->nodes[0];
6566 btrfs_item_key_to_cpu(eb, &found_key, slot);
6567 item_size = btrfs_item_size_nr(eb, slot);
6568
6569 ptr = btrfs_item_ptr(eb, slot,
6570 struct btrfs_dev_stats_item);
6571
6572 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6573 if (item_size >= (1 + i) * sizeof(__le64))
6574 btrfs_dev_stat_set(device, i,
6575 btrfs_dev_stats_value(eb, ptr, i));
6576 else
6577 btrfs_dev_stat_reset(device, i);
6578 }
6579
6580 device->dev_stats_valid = 1;
6581 btrfs_dev_stat_print_on_load(device);
6582 btrfs_release_path(path);
6583 }
6584 mutex_unlock(&fs_devices->device_list_mutex);
6585
6586 out:
6587 btrfs_free_path(path);
6588 return ret < 0 ? ret : 0;
6589 }
6590
6591 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
6592 struct btrfs_root *dev_root,
6593 struct btrfs_device *device)
6594 {
6595 struct btrfs_path *path;
6596 struct btrfs_key key;
6597 struct extent_buffer *eb;
6598 struct btrfs_dev_stats_item *ptr;
6599 int ret;
6600 int i;
6601
6602 key.objectid = 0;
6603 key.type = BTRFS_DEV_STATS_KEY;
6604 key.offset = device->devid;
6605
6606 path = btrfs_alloc_path();
6607 BUG_ON(!path);
6608 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
6609 if (ret < 0) {
6610 printk_in_rcu(KERN_WARNING "BTRFS: "
6611 "error %d while searching for dev_stats item for device %s!\n",
6612 ret, rcu_str_deref(device->name));
6613 goto out;
6614 }
6615
6616 if (ret == 0 &&
6617 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
6618 /* need to delete old one and insert a new one */
6619 ret = btrfs_del_item(trans, dev_root, path);
6620 if (ret != 0) {
6621 printk_in_rcu(KERN_WARNING "BTRFS: "
6622 "delete too small dev_stats item for device %s failed %d!\n",
6623 rcu_str_deref(device->name), ret);
6624 goto out;
6625 }
6626 ret = 1;
6627 }
6628
6629 if (ret == 1) {
6630 /* need to insert a new item */
6631 btrfs_release_path(path);
6632 ret = btrfs_insert_empty_item(trans, dev_root, path,
6633 &key, sizeof(*ptr));
6634 if (ret < 0) {
6635 printk_in_rcu(KERN_WARNING "BTRFS: "
6636 "insert dev_stats item for device %s failed %d!\n",
6637 rcu_str_deref(device->name), ret);
6638 goto out;
6639 }
6640 }
6641
6642 eb = path->nodes[0];
6643 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
6644 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6645 btrfs_set_dev_stats_value(eb, ptr, i,
6646 btrfs_dev_stat_read(device, i));
6647 btrfs_mark_buffer_dirty(eb);
6648
6649 out:
6650 btrfs_free_path(path);
6651 return ret;
6652 }
6653
6654 /*
6655 * called from commit_transaction. Writes all changed device stats to disk.
6656 */
6657 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
6658 struct btrfs_fs_info *fs_info)
6659 {
6660 struct btrfs_root *dev_root = fs_info->dev_root;
6661 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6662 struct btrfs_device *device;
6663 int stats_cnt;
6664 int ret = 0;
6665
6666 mutex_lock(&fs_devices->device_list_mutex);
6667 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6668 if (!device->dev_stats_valid || !btrfs_dev_stats_dirty(device))
6669 continue;
6670
6671 stats_cnt = atomic_read(&device->dev_stats_ccnt);
6672 ret = update_dev_stat_item(trans, dev_root, device);
6673 if (!ret)
6674 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
6675 }
6676 mutex_unlock(&fs_devices->device_list_mutex);
6677
6678 return ret;
6679 }
6680
6681 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
6682 {
6683 btrfs_dev_stat_inc(dev, index);
6684 btrfs_dev_stat_print_on_error(dev);
6685 }
6686
6687 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
6688 {
6689 if (!dev->dev_stats_valid)
6690 return;
6691 printk_ratelimited_in_rcu(KERN_ERR "BTRFS: "
6692 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6693 rcu_str_deref(dev->name),
6694 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6695 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6696 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6697 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6698 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6699 }
6700
6701 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
6702 {
6703 int i;
6704
6705 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6706 if (btrfs_dev_stat_read(dev, i) != 0)
6707 break;
6708 if (i == BTRFS_DEV_STAT_VALUES_MAX)
6709 return; /* all values == 0, suppress message */
6710
6711 printk_in_rcu(KERN_INFO "BTRFS: "
6712 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6713 rcu_str_deref(dev->name),
6714 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6715 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6716 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6717 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6718 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6719 }
6720
6721 int btrfs_get_dev_stats(struct btrfs_root *root,
6722 struct btrfs_ioctl_get_dev_stats *stats)
6723 {
6724 struct btrfs_device *dev;
6725 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6726 int i;
6727
6728 mutex_lock(&fs_devices->device_list_mutex);
6729 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
6730 mutex_unlock(&fs_devices->device_list_mutex);
6731
6732 if (!dev) {
6733 btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
6734 return -ENODEV;
6735 } else if (!dev->dev_stats_valid) {
6736 btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
6737 return -ENODEV;
6738 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
6739 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6740 if (stats->nr_items > i)
6741 stats->values[i] =
6742 btrfs_dev_stat_read_and_reset(dev, i);
6743 else
6744 btrfs_dev_stat_reset(dev, i);
6745 }
6746 } else {
6747 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6748 if (stats->nr_items > i)
6749 stats->values[i] = btrfs_dev_stat_read(dev, i);
6750 }
6751 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
6752 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
6753 return 0;
6754 }
6755
6756 int btrfs_scratch_superblock(struct btrfs_device *device)
6757 {
6758 struct buffer_head *bh;
6759 struct btrfs_super_block *disk_super;
6760
6761 bh = btrfs_read_dev_super(device->bdev);
6762 if (!bh)
6763 return -EINVAL;
6764 disk_super = (struct btrfs_super_block *)bh->b_data;
6765
6766 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
6767 set_buffer_dirty(bh);
6768 sync_dirty_buffer(bh);
6769 brelse(bh);
6770
6771 return 0;
6772 }
6773
6774 /*
6775 * Update the size of all devices, which is used for writing out the
6776 * super blocks.
6777 */
6778 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info)
6779 {
6780 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6781 struct btrfs_device *curr, *next;
6782
6783 if (list_empty(&fs_devices->resized_devices))
6784 return;
6785
6786 mutex_lock(&fs_devices->device_list_mutex);
6787 lock_chunks(fs_info->dev_root);
6788 list_for_each_entry_safe(curr, next, &fs_devices->resized_devices,
6789 resized_list) {
6790 list_del_init(&curr->resized_list);
6791 curr->commit_total_bytes = curr->disk_total_bytes;
6792 }
6793 unlock_chunks(fs_info->dev_root);
6794 mutex_unlock(&fs_devices->device_list_mutex);
6795 }
6796
6797 /* Must be invoked during the transaction commit */
6798 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
6799 struct btrfs_transaction *transaction)
6800 {
6801 struct extent_map *em;
6802 struct map_lookup *map;
6803 struct btrfs_device *dev;
6804 int i;
6805
6806 if (list_empty(&transaction->pending_chunks))
6807 return;
6808
6809 /* In order to kick the device replace finish process */
6810 lock_chunks(root);
6811 list_for_each_entry(em, &transaction->pending_chunks, list) {
6812 map = (struct map_lookup *)em->bdev;
6813
6814 for (i = 0; i < map->num_stripes; i++) {
6815 dev = map->stripes[i].dev;
6816 dev->commit_bytes_used = dev->bytes_used;
6817 }
6818 }
6819 unlock_chunks(root);
6820 }
6821
6822 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info)
6823 {
6824 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6825 while (fs_devices) {
6826 fs_devices->fs_info = fs_info;
6827 fs_devices = fs_devices->seed;
6828 }
6829 }
6830
6831 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info)
6832 {
6833 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6834 while (fs_devices) {
6835 fs_devices->fs_info = NULL;
6836 fs_devices = fs_devices->seed;
6837 }
6838 }
Linux kernel - Deliverables
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