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ARM: pmu: add support for interrupt-affinity property
[linux/fpc-iii.git] / fs / btrfs / volumes.c
blob8222f6f74147972ba1b654c12b013c55a3b60825
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18 #include <linux/sched.h>
19 #include <linux/bio.h>
20 #include <linux/slab.h>
21 #include <linux/buffer_head.h>
22 #include <linux/blkdev.h>
23 #include <linux/random.h>
24 #include <linux/iocontext.h>
25 #include <linux/capability.h>
26 #include <linux/ratelimit.h>
27 #include <linux/kthread.h>
28 #include <linux/raid/pq.h>
29 #include <linux/semaphore.h>
30 #include <asm/div64.h>
31 #include "ctree.h"
32 #include "extent_map.h"
33 #include "disk-io.h"
34 #include "transaction.h"
35 #include "print-tree.h"
36 #include "volumes.h"
37 #include "raid56.h"
38 #include "async-thread.h"
39 #include "check-integrity.h"
40 #include "rcu-string.h"
41 #include "math.h"
42 #include "dev-replace.h"
43 #include "sysfs.h"
44
45 static int init_first_rw_device(struct btrfs_trans_handle *trans,
46 struct btrfs_root *root,
47 struct btrfs_device *device);
48 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
49 static void __btrfs_reset_dev_stats(struct btrfs_device *dev);
50 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev);
51 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
52
53 DEFINE_MUTEX(uuid_mutex);
54 static LIST_HEAD(fs_uuids);
55
56 static struct btrfs_fs_devices *__alloc_fs_devices(void)
57 {
58 struct btrfs_fs_devices *fs_devs;
59
60 fs_devs = kzalloc(sizeof(*fs_devs), GFP_NOFS);
61 if (!fs_devs)
62 return ERR_PTR(-ENOMEM);
63
64 mutex_init(&fs_devs->device_list_mutex);
65
66 INIT_LIST_HEAD(&fs_devs->devices);
67 INIT_LIST_HEAD(&fs_devs->resized_devices);
68 INIT_LIST_HEAD(&fs_devs->alloc_list);
69 INIT_LIST_HEAD(&fs_devs->list);
70
71 return fs_devs;
72 }
73
74 /**
75 * alloc_fs_devices - allocate struct btrfs_fs_devices
76 * @fsid: a pointer to UUID for this FS. If NULL a new UUID is
77 * generated.
78 *
79 * Return: a pointer to a new &struct btrfs_fs_devices on success;
80 * ERR_PTR() on error. Returned struct is not linked onto any lists and
81 * can be destroyed with kfree() right away.
82 */
83 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
84 {
85 struct btrfs_fs_devices *fs_devs;
86
87 fs_devs = __alloc_fs_devices();
88 if (IS_ERR(fs_devs))
89 return fs_devs;
90
91 if (fsid)
92 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
93 else
94 generate_random_uuid(fs_devs->fsid);
95
96 return fs_devs;
97 }
98
99 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
100 {
101 struct btrfs_device *device;
102 WARN_ON(fs_devices->opened);
103 while (!list_empty(&fs_devices->devices)) {
104 device = list_entry(fs_devices->devices.next,
105 struct btrfs_device, dev_list);
106 list_del(&device->dev_list);
107 rcu_string_free(device->name);
108 kfree(device);
109 }
110 kfree(fs_devices);
111 }
112
113 static void btrfs_kobject_uevent(struct block_device *bdev,
114 enum kobject_action action)
115 {
116 int ret;
117
118 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
119 if (ret)
120 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
121 action,
122 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
123 &disk_to_dev(bdev->bd_disk)->kobj);
124 }
125
126 void btrfs_cleanup_fs_uuids(void)
127 {
128 struct btrfs_fs_devices *fs_devices;
129
130 while (!list_empty(&fs_uuids)) {
131 fs_devices = list_entry(fs_uuids.next,
132 struct btrfs_fs_devices, list);
133 list_del(&fs_devices->list);
134 free_fs_devices(fs_devices);
135 }
136 }
137
138 static struct btrfs_device *__alloc_device(void)
139 {
140 struct btrfs_device *dev;
141
142 dev = kzalloc(sizeof(*dev), GFP_NOFS);
143 if (!dev)
144 return ERR_PTR(-ENOMEM);
145
146 INIT_LIST_HEAD(&dev->dev_list);
147 INIT_LIST_HEAD(&dev->dev_alloc_list);
148 INIT_LIST_HEAD(&dev->resized_list);
149
150 spin_lock_init(&dev->io_lock);
151
152 spin_lock_init(&dev->reada_lock);
153 atomic_set(&dev->reada_in_flight, 0);
154 atomic_set(&dev->dev_stats_ccnt, 0);
155 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_WAIT);
156 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_WAIT);
157
158 return dev;
159 }
160
161 static noinline struct btrfs_device *__find_device(struct list_head *head,
162 u64 devid, u8 *uuid)
163 {
164 struct btrfs_device *dev;
165
166 list_for_each_entry(dev, head, dev_list) {
167 if (dev->devid == devid &&
168 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
169 return dev;
170 }
171 }
172 return NULL;
173 }
174
175 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
176 {
177 struct btrfs_fs_devices *fs_devices;
178
179 list_for_each_entry(fs_devices, &fs_uuids, list) {
180 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
181 return fs_devices;
182 }
183 return NULL;
184 }
185
186 static int
187 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
188 int flush, struct block_device **bdev,
189 struct buffer_head **bh)
190 {
191 int ret;
192
193 *bdev = blkdev_get_by_path(device_path, flags, holder);
194
195 if (IS_ERR(*bdev)) {
196 ret = PTR_ERR(*bdev);
197 printk(KERN_INFO "BTRFS: open %s failed\n", device_path);
198 goto error;
199 }
200
201 if (flush)
202 filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
203 ret = set_blocksize(*bdev, 4096);
204 if (ret) {
205 blkdev_put(*bdev, flags);
206 goto error;
207 }
208 invalidate_bdev(*bdev);
209 *bh = btrfs_read_dev_super(*bdev);
210 if (!*bh) {
211 ret = -EINVAL;
212 blkdev_put(*bdev, flags);
213 goto error;
214 }
215
216 return 0;
217
218 error:
219 *bdev = NULL;
220 *bh = NULL;
221 return ret;
222 }
223
224 static void requeue_list(struct btrfs_pending_bios *pending_bios,
225 struct bio *head, struct bio *tail)
226 {
227
228 struct bio *old_head;
229
230 old_head = pending_bios->head;
231 pending_bios->head = head;
232 if (pending_bios->tail)
233 tail->bi_next = old_head;
234 else
235 pending_bios->tail = tail;
236 }
237
238 /*
239 * we try to collect pending bios for a device so we don't get a large
240 * number of procs sending bios down to the same device. This greatly
241 * improves the schedulers ability to collect and merge the bios.
242 *
243 * But, it also turns into a long list of bios to process and that is sure
244 * to eventually make the worker thread block. The solution here is to
245 * make some progress and then put this work struct back at the end of
246 * the list if the block device is congested. This way, multiple devices
247 * can make progress from a single worker thread.
248 */
249 static noinline void run_scheduled_bios(struct btrfs_device *device)
250 {
251 struct bio *pending;
252 struct backing_dev_info *bdi;
253 struct btrfs_fs_info *fs_info;
254 struct btrfs_pending_bios *pending_bios;
255 struct bio *tail;
256 struct bio *cur;
257 int again = 0;
258 unsigned long num_run;
259 unsigned long batch_run = 0;
260 unsigned long limit;
261 unsigned long last_waited = 0;
262 int force_reg = 0;
263 int sync_pending = 0;
264 struct blk_plug plug;
265
266 /*
267 * this function runs all the bios we've collected for
268 * a particular device. We don't want to wander off to
269 * another device without first sending all of these down.
270 * So, setup a plug here and finish it off before we return
271 */
272 blk_start_plug(&plug);
273
274 bdi = blk_get_backing_dev_info(device->bdev);
275 fs_info = device->dev_root->fs_info;
276 limit = btrfs_async_submit_limit(fs_info);
277 limit = limit * 2 / 3;
278
279 loop:
280 spin_lock(&device->io_lock);
281
282 loop_lock:
283 num_run = 0;
284
285 /* take all the bios off the list at once and process them
286 * later on (without the lock held). But, remember the
287 * tail and other pointers so the bios can be properly reinserted
288 * into the list if we hit congestion
289 */
290 if (!force_reg && device->pending_sync_bios.head) {
291 pending_bios = &device->pending_sync_bios;
292 force_reg = 1;
293 } else {
294 pending_bios = &device->pending_bios;
295 force_reg = 0;
296 }
297
298 pending = pending_bios->head;
299 tail = pending_bios->tail;
300 WARN_ON(pending && !tail);
301
302 /*
303 * if pending was null this time around, no bios need processing
304 * at all and we can stop. Otherwise it'll loop back up again
305 * and do an additional check so no bios are missed.
306 *
307 * device->running_pending is used to synchronize with the
308 * schedule_bio code.
309 */
310 if (device->pending_sync_bios.head == NULL &&
311 device->pending_bios.head == NULL) {
312 again = 0;
313 device->running_pending = 0;
314 } else {
315 again = 1;
316 device->running_pending = 1;
317 }
318
319 pending_bios->head = NULL;
320 pending_bios->tail = NULL;
321
322 spin_unlock(&device->io_lock);
323
324 while (pending) {
325
326 rmb();
327 /* we want to work on both lists, but do more bios on the
328 * sync list than the regular list
329 */
330 if ((num_run > 32 &&
331 pending_bios != &device->pending_sync_bios &&
332 device->pending_sync_bios.head) ||
333 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
334 device->pending_bios.head)) {
335 spin_lock(&device->io_lock);
336 requeue_list(pending_bios, pending, tail);
337 goto loop_lock;
338 }
339
340 cur = pending;
341 pending = pending->bi_next;
342 cur->bi_next = NULL;
343
344 if (atomic_dec_return(&fs_info->nr_async_bios) < limit &&
345 waitqueue_active(&fs_info->async_submit_wait))
346 wake_up(&fs_info->async_submit_wait);
347
348 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
349
350 /*
351 * if we're doing the sync list, record that our
352 * plug has some sync requests on it
353 *
354 * If we're doing the regular list and there are
355 * sync requests sitting around, unplug before
356 * we add more
357 */
358 if (pending_bios == &device->pending_sync_bios) {
359 sync_pending = 1;
360 } else if (sync_pending) {
361 blk_finish_plug(&plug);
362 blk_start_plug(&plug);
363 sync_pending = 0;
364 }
365
366 btrfsic_submit_bio(cur->bi_rw, cur);
367 num_run++;
368 batch_run++;
369 if (need_resched())
370 cond_resched();
371
372 /*
373 * we made progress, there is more work to do and the bdi
374 * is now congested. Back off and let other work structs
375 * run instead
376 */
377 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
378 fs_info->fs_devices->open_devices > 1) {
379 struct io_context *ioc;
380
381 ioc = current->io_context;
382
383 /*
384 * the main goal here is that we don't want to
385 * block if we're going to be able to submit
386 * more requests without blocking.
387 *
388 * This code does two great things, it pokes into
389 * the elevator code from a filesystem _and_
390 * it makes assumptions about how batching works.
391 */
392 if (ioc && ioc->nr_batch_requests > 0 &&
393 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
394 (last_waited == 0 ||
395 ioc->last_waited == last_waited)) {
396 /*
397 * we want to go through our batch of
398 * requests and stop. So, we copy out
399 * the ioc->last_waited time and test
400 * against it before looping
401 */
402 last_waited = ioc->last_waited;
403 if (need_resched())
404 cond_resched();
405 continue;
406 }
407 spin_lock(&device->io_lock);
408 requeue_list(pending_bios, pending, tail);
409 device->running_pending = 1;
410
411 spin_unlock(&device->io_lock);
412 btrfs_queue_work(fs_info->submit_workers,
413 &device->work);
414 goto done;
415 }
416 /* unplug every 64 requests just for good measure */
417 if (batch_run % 64 == 0) {
418 blk_finish_plug(&plug);
419 blk_start_plug(&plug);
420 sync_pending = 0;
421 }
422 }
423
424 cond_resched();
425 if (again)
426 goto loop;
427
428 spin_lock(&device->io_lock);
429 if (device->pending_bios.head || device->pending_sync_bios.head)
430 goto loop_lock;
431 spin_unlock(&device->io_lock);
432
433 done:
434 blk_finish_plug(&plug);
435 }
436
437 static void pending_bios_fn(struct btrfs_work *work)
438 {
439 struct btrfs_device *device;
440
441 device = container_of(work, struct btrfs_device, work);
442 run_scheduled_bios(device);
443 }
444
445 /*
446 * Add new device to list of registered devices
447 *
448 * Returns:
449 * 1 - first time device is seen
450 * 0 - device already known
451 * < 0 - error
452 */
453 static noinline int device_list_add(const char *path,
454 struct btrfs_super_block *disk_super,
455 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
456 {
457 struct btrfs_device *device;
458 struct btrfs_fs_devices *fs_devices;
459 struct rcu_string *name;
460 int ret = 0;
461 u64 found_transid = btrfs_super_generation(disk_super);
462
463 fs_devices = find_fsid(disk_super->fsid);
464 if (!fs_devices) {
465 fs_devices = alloc_fs_devices(disk_super->fsid);
466 if (IS_ERR(fs_devices))
467 return PTR_ERR(fs_devices);
468
469 list_add(&fs_devices->list, &fs_uuids);
470
471 device = NULL;
472 } else {
473 device = __find_device(&fs_devices->devices, devid,
474 disk_super->dev_item.uuid);
475 }
476
477 if (!device) {
478 if (fs_devices->opened)
479 return -EBUSY;
480
481 device = btrfs_alloc_device(NULL, &devid,
482 disk_super->dev_item.uuid);
483 if (IS_ERR(device)) {
484 /* we can safely leave the fs_devices entry around */
485 return PTR_ERR(device);
486 }
487
488 name = rcu_string_strdup(path, GFP_NOFS);
489 if (!name) {
490 kfree(device);
491 return -ENOMEM;
492 }
493 rcu_assign_pointer(device->name, name);
494
495 mutex_lock(&fs_devices->device_list_mutex);
496 list_add_rcu(&device->dev_list, &fs_devices->devices);
497 fs_devices->num_devices++;
498 mutex_unlock(&fs_devices->device_list_mutex);
499
500 ret = 1;
501 device->fs_devices = fs_devices;
502 } else if (!device->name || strcmp(device->name->str, path)) {
503 /*
504 * When FS is already mounted.
505 * 1. If you are here and if the device->name is NULL that
506 * means this device was missing at time of FS mount.
507 * 2. If you are here and if the device->name is different
508 * from 'path' that means either
509 * a. The same device disappeared and reappeared with
510 * different name. or
511 * b. The missing-disk-which-was-replaced, has
512 * reappeared now.
513 *
514 * We must allow 1 and 2a above. But 2b would be a spurious
515 * and unintentional.
516 *
517 * Further in case of 1 and 2a above, the disk at 'path'
518 * would have missed some transaction when it was away and
519 * in case of 2a the stale bdev has to be updated as well.
520 * 2b must not be allowed at all time.
521 */
522
523 /*
524 * For now, we do allow update to btrfs_fs_device through the
525 * btrfs dev scan cli after FS has been mounted. We're still
526 * tracking a problem where systems fail mount by subvolume id
527 * when we reject replacement on a mounted FS.
528 */
529 if (!fs_devices->opened && found_transid < device->generation) {
530 /*
531 * That is if the FS is _not_ mounted and if you
532 * are here, that means there is more than one
533 * disk with same uuid and devid.We keep the one
534 * with larger generation number or the last-in if
535 * generation are equal.
536 */
537 return -EEXIST;
538 }
539
540 name = rcu_string_strdup(path, GFP_NOFS);
541 if (!name)
542 return -ENOMEM;
543 rcu_string_free(device->name);
544 rcu_assign_pointer(device->name, name);
545 if (device->missing) {
546 fs_devices->missing_devices--;
547 device->missing = 0;
548 }
549 }
550
551 /*
552 * Unmount does not free the btrfs_device struct but would zero
553 * generation along with most of the other members. So just update
554 * it back. We need it to pick the disk with largest generation
555 * (as above).
556 */
557 if (!fs_devices->opened)
558 device->generation = found_transid;
559
560 *fs_devices_ret = fs_devices;
561
562 return ret;
563 }
564
565 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
566 {
567 struct btrfs_fs_devices *fs_devices;
568 struct btrfs_device *device;
569 struct btrfs_device *orig_dev;
570
571 fs_devices = alloc_fs_devices(orig->fsid);
572 if (IS_ERR(fs_devices))
573 return fs_devices;
574
575 mutex_lock(&orig->device_list_mutex);
576 fs_devices->total_devices = orig->total_devices;
577
578 /* We have held the volume lock, it is safe to get the devices. */
579 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
580 struct rcu_string *name;
581
582 device = btrfs_alloc_device(NULL, &orig_dev->devid,
583 orig_dev->uuid);
584 if (IS_ERR(device))
585 goto error;
586
587 /*
588 * This is ok to do without rcu read locked because we hold the
589 * uuid mutex so nothing we touch in here is going to disappear.
590 */
591 if (orig_dev->name) {
592 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
593 if (!name) {
594 kfree(device);
595 goto error;
596 }
597 rcu_assign_pointer(device->name, name);
598 }
599
600 list_add(&device->dev_list, &fs_devices->devices);
601 device->fs_devices = fs_devices;
602 fs_devices->num_devices++;
603 }
604 mutex_unlock(&orig->device_list_mutex);
605 return fs_devices;
606 error:
607 mutex_unlock(&orig->device_list_mutex);
608 free_fs_devices(fs_devices);
609 return ERR_PTR(-ENOMEM);
610 }
611
612 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info,
613 struct btrfs_fs_devices *fs_devices, int step)
614 {
615 struct btrfs_device *device, *next;
616 struct btrfs_device *latest_dev = NULL;
617
618 mutex_lock(&uuid_mutex);
619 again:
620 /* This is the initialized path, it is safe to release the devices. */
621 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
622 if (device->in_fs_metadata) {
623 if (!device->is_tgtdev_for_dev_replace &&
624 (!latest_dev ||
625 device->generation > latest_dev->generation)) {
626 latest_dev = device;
627 }
628 continue;
629 }
630
631 if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
632 /*
633 * In the first step, keep the device which has
634 * the correct fsid and the devid that is used
635 * for the dev_replace procedure.
636 * In the second step, the dev_replace state is
637 * read from the device tree and it is known
638 * whether the procedure is really active or
639 * not, which means whether this device is
640 * used or whether it should be removed.
641 */
642 if (step == 0 || device->is_tgtdev_for_dev_replace) {
643 continue;
644 }
645 }
646 if (device->bdev) {
647 blkdev_put(device->bdev, device->mode);
648 device->bdev = NULL;
649 fs_devices->open_devices--;
650 }
651 if (device->writeable) {
652 list_del_init(&device->dev_alloc_list);
653 device->writeable = 0;
654 if (!device->is_tgtdev_for_dev_replace)
655 fs_devices->rw_devices--;
656 }
657 list_del_init(&device->dev_list);
658 fs_devices->num_devices--;
659 rcu_string_free(device->name);
660 kfree(device);
661 }
662
663 if (fs_devices->seed) {
664 fs_devices = fs_devices->seed;
665 goto again;
666 }
667
668 fs_devices->latest_bdev = latest_dev->bdev;
669
670 mutex_unlock(&uuid_mutex);
671 }
672
673 static void __free_device(struct work_struct *work)
674 {
675 struct btrfs_device *device;
676
677 device = container_of(work, struct btrfs_device, rcu_work);
678
679 if (device->bdev)
680 blkdev_put(device->bdev, device->mode);
681
682 rcu_string_free(device->name);
683 kfree(device);
684 }
685
686 static void free_device(struct rcu_head *head)
687 {
688 struct btrfs_device *device;
689
690 device = container_of(head, struct btrfs_device, rcu);
691
692 INIT_WORK(&device->rcu_work, __free_device);
693 schedule_work(&device->rcu_work);
694 }
695
696 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
697 {
698 struct btrfs_device *device;
699
700 if (--fs_devices->opened > 0)
701 return 0;
702
703 mutex_lock(&fs_devices->device_list_mutex);
704 list_for_each_entry(device, &fs_devices->devices, dev_list) {
705 struct btrfs_device *new_device;
706 struct rcu_string *name;
707
708 if (device->bdev)
709 fs_devices->open_devices--;
710
711 if (device->writeable &&
712 device->devid != BTRFS_DEV_REPLACE_DEVID) {
713 list_del_init(&device->dev_alloc_list);
714 fs_devices->rw_devices--;
715 }
716
717 if (device->missing)
718 fs_devices->missing_devices--;
719
720 new_device = btrfs_alloc_device(NULL, &device->devid,
721 device->uuid);
722 BUG_ON(IS_ERR(new_device)); /* -ENOMEM */
723
724 /* Safe because we are under uuid_mutex */
725 if (device->name) {
726 name = rcu_string_strdup(device->name->str, GFP_NOFS);
727 BUG_ON(!name); /* -ENOMEM */
728 rcu_assign_pointer(new_device->name, name);
729 }
730
731 list_replace_rcu(&device->dev_list, &new_device->dev_list);
732 new_device->fs_devices = device->fs_devices;
733
734 call_rcu(&device->rcu, free_device);
735 }
736 mutex_unlock(&fs_devices->device_list_mutex);
737
738 WARN_ON(fs_devices->open_devices);
739 WARN_ON(fs_devices->rw_devices);
740 fs_devices->opened = 0;
741 fs_devices->seeding = 0;
742
743 return 0;
744 }
745
746 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
747 {
748 struct btrfs_fs_devices *seed_devices = NULL;
749 int ret;
750
751 mutex_lock(&uuid_mutex);
752 ret = __btrfs_close_devices(fs_devices);
753 if (!fs_devices->opened) {
754 seed_devices = fs_devices->seed;
755 fs_devices->seed = NULL;
756 }
757 mutex_unlock(&uuid_mutex);
758
759 while (seed_devices) {
760 fs_devices = seed_devices;
761 seed_devices = fs_devices->seed;
762 __btrfs_close_devices(fs_devices);
763 free_fs_devices(fs_devices);
764 }
765 /*
766 * Wait for rcu kworkers under __btrfs_close_devices
767 * to finish all blkdev_puts so device is really
768 * free when umount is done.
769 */
770 rcu_barrier();
771 return ret;
772 }
773
774 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
775 fmode_t flags, void *holder)
776 {
777 struct request_queue *q;
778 struct block_device *bdev;
779 struct list_head *head = &fs_devices->devices;
780 struct btrfs_device *device;
781 struct btrfs_device *latest_dev = NULL;
782 struct buffer_head *bh;
783 struct btrfs_super_block *disk_super;
784 u64 devid;
785 int seeding = 1;
786 int ret = 0;
787
788 flags |= FMODE_EXCL;
789
790 list_for_each_entry(device, head, dev_list) {
791 if (device->bdev)
792 continue;
793 if (!device->name)
794 continue;
795
796 /* Just open everything we can; ignore failures here */
797 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
798 &bdev, &bh))
799 continue;
800
801 disk_super = (struct btrfs_super_block *)bh->b_data;
802 devid = btrfs_stack_device_id(&disk_super->dev_item);
803 if (devid != device->devid)
804 goto error_brelse;
805
806 if (memcmp(device->uuid, disk_super->dev_item.uuid,
807 BTRFS_UUID_SIZE))
808 goto error_brelse;
809
810 device->generation = btrfs_super_generation(disk_super);
811 if (!latest_dev ||
812 device->generation > latest_dev->generation)
813 latest_dev = device;
814
815 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
816 device->writeable = 0;
817 } else {
818 device->writeable = !bdev_read_only(bdev);
819 seeding = 0;
820 }
821
822 q = bdev_get_queue(bdev);
823 if (blk_queue_discard(q))
824 device->can_discard = 1;
825
826 device->bdev = bdev;
827 device->in_fs_metadata = 0;
828 device->mode = flags;
829
830 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
831 fs_devices->rotating = 1;
832
833 fs_devices->open_devices++;
834 if (device->writeable &&
835 device->devid != BTRFS_DEV_REPLACE_DEVID) {
836 fs_devices->rw_devices++;
837 list_add(&device->dev_alloc_list,
838 &fs_devices->alloc_list);
839 }
840 brelse(bh);
841 continue;
842
843 error_brelse:
844 brelse(bh);
845 blkdev_put(bdev, flags);
846 continue;
847 }
848 if (fs_devices->open_devices == 0) {
849 ret = -EINVAL;
850 goto out;
851 }
852 fs_devices->seeding = seeding;
853 fs_devices->opened = 1;
854 fs_devices->latest_bdev = latest_dev->bdev;
855 fs_devices->total_rw_bytes = 0;
856 out:
857 return ret;
858 }
859
860 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
861 fmode_t flags, void *holder)
862 {
863 int ret;
864
865 mutex_lock(&uuid_mutex);
866 if (fs_devices->opened) {
867 fs_devices->opened++;
868 ret = 0;
869 } else {
870 ret = __btrfs_open_devices(fs_devices, flags, holder);
871 }
872 mutex_unlock(&uuid_mutex);
873 return ret;
874 }
875
876 /*
877 * Look for a btrfs signature on a device. This may be called out of the mount path
878 * and we are not allowed to call set_blocksize during the scan. The superblock
879 * is read via pagecache
880 */
881 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
882 struct btrfs_fs_devices **fs_devices_ret)
883 {
884 struct btrfs_super_block *disk_super;
885 struct block_device *bdev;
886 struct page *page;
887 void *p;
888 int ret = -EINVAL;
889 u64 devid;
890 u64 transid;
891 u64 total_devices;
892 u64 bytenr;
893 pgoff_t index;
894
895 /*
896 * we would like to check all the supers, but that would make
897 * a btrfs mount succeed after a mkfs from a different FS.
898 * So, we need to add a special mount option to scan for
899 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
900 */
901 bytenr = btrfs_sb_offset(0);
902 flags |= FMODE_EXCL;
903 mutex_lock(&uuid_mutex);
904
905 bdev = blkdev_get_by_path(path, flags, holder);
906
907 if (IS_ERR(bdev)) {
908 ret = PTR_ERR(bdev);
909 goto error;
910 }
911
912 /* make sure our super fits in the device */
913 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode))
914 goto error_bdev_put;
915
916 /* make sure our super fits in the page */
917 if (sizeof(*disk_super) > PAGE_CACHE_SIZE)
918 goto error_bdev_put;
919
920 /* make sure our super doesn't straddle pages on disk */
921 index = bytenr >> PAGE_CACHE_SHIFT;
922 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index)
923 goto error_bdev_put;
924
925 /* pull in the page with our super */
926 page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
927 index, GFP_NOFS);
928
929 if (IS_ERR_OR_NULL(page))
930 goto error_bdev_put;
931
932 p = kmap(page);
933
934 /* align our pointer to the offset of the super block */
935 disk_super = p + (bytenr & ~PAGE_CACHE_MASK);
936
937 if (btrfs_super_bytenr(disk_super) != bytenr ||
938 btrfs_super_magic(disk_super) != BTRFS_MAGIC)
939 goto error_unmap;
940
941 devid = btrfs_stack_device_id(&disk_super->dev_item);
942 transid = btrfs_super_generation(disk_super);
943 total_devices = btrfs_super_num_devices(disk_super);
944
945 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
946 if (ret > 0) {
947 if (disk_super->label[0]) {
948 if (disk_super->label[BTRFS_LABEL_SIZE - 1])
949 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
950 printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
951 } else {
952 printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
953 }
954
955 printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
956 ret = 0;
957 }
958 if (!ret && fs_devices_ret)
959 (*fs_devices_ret)->total_devices = total_devices;
960
961 error_unmap:
962 kunmap(page);
963 page_cache_release(page);
964
965 error_bdev_put:
966 blkdev_put(bdev, flags);
967 error:
968 mutex_unlock(&uuid_mutex);
969 return ret;
970 }
971
972 /* helper to account the used device space in the range */
973 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
974 u64 end, u64 *length)
975 {
976 struct btrfs_key key;
977 struct btrfs_root *root = device->dev_root;
978 struct btrfs_dev_extent *dev_extent;
979 struct btrfs_path *path;
980 u64 extent_end;
981 int ret;
982 int slot;
983 struct extent_buffer *l;
984
985 *length = 0;
986
987 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
988 return 0;
989
990 path = btrfs_alloc_path();
991 if (!path)
992 return -ENOMEM;
993 path->reada = 2;
994
995 key.objectid = device->devid;
996 key.offset = start;
997 key.type = BTRFS_DEV_EXTENT_KEY;
998
999 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1000 if (ret < 0)
1001 goto out;
1002 if (ret > 0) {
1003 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1004 if (ret < 0)
1005 goto out;
1006 }
1007
1008 while (1) {
1009 l = path->nodes[0];
1010 slot = path->slots[0];
1011 if (slot >= btrfs_header_nritems(l)) {
1012 ret = btrfs_next_leaf(root, path);
1013 if (ret == 0)
1014 continue;
1015 if (ret < 0)
1016 goto out;
1017
1018 break;
1019 }
1020 btrfs_item_key_to_cpu(l, &key, slot);
1021
1022 if (key.objectid < device->devid)
1023 goto next;
1024
1025 if (key.objectid > device->devid)
1026 break;
1027
1028 if (key.type != BTRFS_DEV_EXTENT_KEY)
1029 goto next;
1030
1031 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1032 extent_end = key.offset + btrfs_dev_extent_length(l,
1033 dev_extent);
1034 if (key.offset <= start && extent_end > end) {
1035 *length = end - start + 1;
1036 break;
1037 } else if (key.offset <= start && extent_end > start)
1038 *length += extent_end - start;
1039 else if (key.offset > start && extent_end <= end)
1040 *length += extent_end - key.offset;
1041 else if (key.offset > start && key.offset <= end) {
1042 *length += end - key.offset + 1;
1043 break;
1044 } else if (key.offset > end)
1045 break;
1046
1047 next:
1048 path->slots[0]++;
1049 }
1050 ret = 0;
1051 out:
1052 btrfs_free_path(path);
1053 return ret;
1054 }
1055
1056 static int contains_pending_extent(struct btrfs_trans_handle *trans,
1057 struct btrfs_device *device,
1058 u64 *start, u64 len)
1059 {
1060 struct extent_map *em;
1061 struct list_head *search_list = &trans->transaction->pending_chunks;
1062 int ret = 0;
1063
1064 again:
1065 list_for_each_entry(em, search_list, list) {
1066 struct map_lookup *map;
1067 int i;
1068
1069 map = (struct map_lookup *)em->bdev;
1070 for (i = 0; i < map->num_stripes; i++) {
1071 if (map->stripes[i].dev != device)
1072 continue;
1073 if (map->stripes[i].physical >= *start + len ||
1074 map->stripes[i].physical + em->orig_block_len <=
1075 *start)
1076 continue;
1077 *start = map->stripes[i].physical +
1078 em->orig_block_len;
1079 ret = 1;
1080 }
1081 }
1082 if (search_list == &trans->transaction->pending_chunks) {
1083 search_list = &trans->root->fs_info->pinned_chunks;
1084 goto again;
1085 }
1086
1087 return ret;
1088 }
1089
1090
1091 /*
1092 * find_free_dev_extent - find free space in the specified device
1093 * @device: the device which we search the free space in
1094 * @num_bytes: the size of the free space that we need
1095 * @start: store the start of the free space.
1096 * @len: the size of the free space. that we find, or the size of the max
1097 * free space if we don't find suitable free space
1098 *
1099 * this uses a pretty simple search, the expectation is that it is
1100 * called very infrequently and that a given device has a small number
1101 * of extents
1102 *
1103 * @start is used to store the start of the free space if we find. But if we
1104 * don't find suitable free space, it will be used to store the start position
1105 * of the max free space.
1106 *
1107 * @len is used to store the size of the free space that we find.
1108 * But if we don't find suitable free space, it is used to store the size of
1109 * the max free space.
1110 */
1111 int find_free_dev_extent(struct btrfs_trans_handle *trans,
1112 struct btrfs_device *device, u64 num_bytes,
1113 u64 *start, u64 *len)
1114 {
1115 struct btrfs_key key;
1116 struct btrfs_root *root = device->dev_root;
1117 struct btrfs_dev_extent *dev_extent;
1118 struct btrfs_path *path;
1119 u64 hole_size;
1120 u64 max_hole_start;
1121 u64 max_hole_size;
1122 u64 extent_end;
1123 u64 search_start;
1124 u64 search_end = device->total_bytes;
1125 int ret;
1126 int slot;
1127 struct extent_buffer *l;
1128
1129 /* FIXME use last free of some kind */
1130
1131 /* we don't want to overwrite the superblock on the drive,
1132 * so we make sure to start at an offset of at least 1MB
1133 */
1134 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
1135
1136 path = btrfs_alloc_path();
1137 if (!path)
1138 return -ENOMEM;
1139 again:
1140 max_hole_start = search_start;
1141 max_hole_size = 0;
1142 hole_size = 0;
1143
1144 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
1145 ret = -ENOSPC;
1146 goto out;
1147 }
1148
1149 path->reada = 2;
1150 path->search_commit_root = 1;
1151 path->skip_locking = 1;
1152
1153 key.objectid = device->devid;
1154 key.offset = search_start;
1155 key.type = BTRFS_DEV_EXTENT_KEY;
1156
1157 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1158 if (ret < 0)
1159 goto out;
1160 if (ret > 0) {
1161 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1162 if (ret < 0)
1163 goto out;
1164 }
1165
1166 while (1) {
1167 l = path->nodes[0];
1168 slot = path->slots[0];
1169 if (slot >= btrfs_header_nritems(l)) {
1170 ret = btrfs_next_leaf(root, path);
1171 if (ret == 0)
1172 continue;
1173 if (ret < 0)
1174 goto out;
1175
1176 break;
1177 }
1178 btrfs_item_key_to_cpu(l, &key, slot);
1179
1180 if (key.objectid < device->devid)
1181 goto next;
1182
1183 if (key.objectid > device->devid)
1184 break;
1185
1186 if (key.type != BTRFS_DEV_EXTENT_KEY)
1187 goto next;
1188
1189 if (key.offset > search_start) {
1190 hole_size = key.offset - search_start;
1191
1192 /*
1193 * Have to check before we set max_hole_start, otherwise
1194 * we could end up sending back this offset anyway.
1195 */
1196 if (contains_pending_extent(trans, device,
1197 &search_start,
1198 hole_size))
1199 hole_size = 0;
1200
1201 if (hole_size > max_hole_size) {
1202 max_hole_start = search_start;
1203 max_hole_size = hole_size;
1204 }
1205
1206 /*
1207 * If this free space is greater than which we need,
1208 * it must be the max free space that we have found
1209 * until now, so max_hole_start must point to the start
1210 * of this free space and the length of this free space
1211 * is stored in max_hole_size. Thus, we return
1212 * max_hole_start and max_hole_size and go back to the
1213 * caller.
1214 */
1215 if (hole_size >= num_bytes) {
1216 ret = 0;
1217 goto out;
1218 }
1219 }
1220
1221 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1222 extent_end = key.offset + btrfs_dev_extent_length(l,
1223 dev_extent);
1224 if (extent_end > search_start)
1225 search_start = extent_end;
1226 next:
1227 path->slots[0]++;
1228 cond_resched();
1229 }
1230
1231 /*
1232 * At this point, search_start should be the end of
1233 * allocated dev extents, and when shrinking the device,
1234 * search_end may be smaller than search_start.
1235 */
1236 if (search_end > search_start)
1237 hole_size = search_end - search_start;
1238
1239 if (hole_size > max_hole_size) {
1240 max_hole_start = search_start;
1241 max_hole_size = hole_size;
1242 }
1243
1244 if (contains_pending_extent(trans, device, &search_start, hole_size)) {
1245 btrfs_release_path(path);
1246 goto again;
1247 }
1248
1249 /* See above. */
1250 if (hole_size < num_bytes)
1251 ret = -ENOSPC;
1252 else
1253 ret = 0;
1254
1255 out:
1256 btrfs_free_path(path);
1257 *start = max_hole_start;
1258 if (len)
1259 *len = max_hole_size;
1260 return ret;
1261 }
1262
1263 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1264 struct btrfs_device *device,
1265 u64 start, u64 *dev_extent_len)
1266 {
1267 int ret;
1268 struct btrfs_path *path;
1269 struct btrfs_root *root = device->dev_root;
1270 struct btrfs_key key;
1271 struct btrfs_key found_key;
1272 struct extent_buffer *leaf = NULL;
1273 struct btrfs_dev_extent *extent = NULL;
1274
1275 path = btrfs_alloc_path();
1276 if (!path)
1277 return -ENOMEM;
1278
1279 key.objectid = device->devid;
1280 key.offset = start;
1281 key.type = BTRFS_DEV_EXTENT_KEY;
1282 again:
1283 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1284 if (ret > 0) {
1285 ret = btrfs_previous_item(root, path, key.objectid,
1286 BTRFS_DEV_EXTENT_KEY);
1287 if (ret)
1288 goto out;
1289 leaf = path->nodes[0];
1290 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1291 extent = btrfs_item_ptr(leaf, path->slots[0],
1292 struct btrfs_dev_extent);
1293 BUG_ON(found_key.offset > start || found_key.offset +
1294 btrfs_dev_extent_length(leaf, extent) < start);
1295 key = found_key;
1296 btrfs_release_path(path);
1297 goto again;
1298 } else if (ret == 0) {
1299 leaf = path->nodes[0];
1300 extent = btrfs_item_ptr(leaf, path->slots[0],
1301 struct btrfs_dev_extent);
1302 } else {
1303 btrfs_error(root->fs_info, ret, "Slot search failed");
1304 goto out;
1305 }
1306
1307 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1308
1309 ret = btrfs_del_item(trans, root, path);
1310 if (ret) {
1311 btrfs_error(root->fs_info, ret,
1312 "Failed to remove dev extent item");
1313 } else {
1314 trans->transaction->have_free_bgs = 1;
1315 }
1316 out:
1317 btrfs_free_path(path);
1318 return ret;
1319 }
1320
1321 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1322 struct btrfs_device *device,
1323 u64 chunk_tree, u64 chunk_objectid,
1324 u64 chunk_offset, u64 start, u64 num_bytes)
1325 {
1326 int ret;
1327 struct btrfs_path *path;
1328 struct btrfs_root *root = device->dev_root;
1329 struct btrfs_dev_extent *extent;
1330 struct extent_buffer *leaf;
1331 struct btrfs_key key;
1332
1333 WARN_ON(!device->in_fs_metadata);
1334 WARN_ON(device->is_tgtdev_for_dev_replace);
1335 path = btrfs_alloc_path();
1336 if (!path)
1337 return -ENOMEM;
1338
1339 key.objectid = device->devid;
1340 key.offset = start;
1341 key.type = BTRFS_DEV_EXTENT_KEY;
1342 ret = btrfs_insert_empty_item(trans, root, path, &key,
1343 sizeof(*extent));
1344 if (ret)
1345 goto out;
1346
1347 leaf = path->nodes[0];
1348 extent = btrfs_item_ptr(leaf, path->slots[0],
1349 struct btrfs_dev_extent);
1350 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1351 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1352 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1353
1354 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1355 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE);
1356
1357 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1358 btrfs_mark_buffer_dirty(leaf);
1359 out:
1360 btrfs_free_path(path);
1361 return ret;
1362 }
1363
1364 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1365 {
1366 struct extent_map_tree *em_tree;
1367 struct extent_map *em;
1368 struct rb_node *n;
1369 u64 ret = 0;
1370
1371 em_tree = &fs_info->mapping_tree.map_tree;
1372 read_lock(&em_tree->lock);
1373 n = rb_last(&em_tree->map);
1374 if (n) {
1375 em = rb_entry(n, struct extent_map, rb_node);
1376 ret = em->start + em->len;
1377 }
1378 read_unlock(&em_tree->lock);
1379
1380 return ret;
1381 }
1382
1383 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1384 u64 *devid_ret)
1385 {
1386 int ret;
1387 struct btrfs_key key;
1388 struct btrfs_key found_key;
1389 struct btrfs_path *path;
1390
1391 path = btrfs_alloc_path();
1392 if (!path)
1393 return -ENOMEM;
1394
1395 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1396 key.type = BTRFS_DEV_ITEM_KEY;
1397 key.offset = (u64)-1;
1398
1399 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1400 if (ret < 0)
1401 goto error;
1402
1403 BUG_ON(ret == 0); /* Corruption */
1404
1405 ret = btrfs_previous_item(fs_info->chunk_root, path,
1406 BTRFS_DEV_ITEMS_OBJECTID,
1407 BTRFS_DEV_ITEM_KEY);
1408 if (ret) {
1409 *devid_ret = 1;
1410 } else {
1411 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1412 path->slots[0]);
1413 *devid_ret = found_key.offset + 1;
1414 }
1415 ret = 0;
1416 error:
1417 btrfs_free_path(path);
1418 return ret;
1419 }
1420
1421 /*
1422 * the device information is stored in the chunk root
1423 * the btrfs_device struct should be fully filled in
1424 */
1425 static int btrfs_add_device(struct btrfs_trans_handle *trans,
1426 struct btrfs_root *root,
1427 struct btrfs_device *device)
1428 {
1429 int ret;
1430 struct btrfs_path *path;
1431 struct btrfs_dev_item *dev_item;
1432 struct extent_buffer *leaf;
1433 struct btrfs_key key;
1434 unsigned long ptr;
1435
1436 root = root->fs_info->chunk_root;
1437
1438 path = btrfs_alloc_path();
1439 if (!path)
1440 return -ENOMEM;
1441
1442 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1443 key.type = BTRFS_DEV_ITEM_KEY;
1444 key.offset = device->devid;
1445
1446 ret = btrfs_insert_empty_item(trans, root, path, &key,
1447 sizeof(*dev_item));
1448 if (ret)
1449 goto out;
1450
1451 leaf = path->nodes[0];
1452 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1453
1454 btrfs_set_device_id(leaf, dev_item, device->devid);
1455 btrfs_set_device_generation(leaf, dev_item, 0);
1456 btrfs_set_device_type(leaf, dev_item, device->type);
1457 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1458 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1459 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1460 btrfs_set_device_total_bytes(leaf, dev_item,
1461 btrfs_device_get_disk_total_bytes(device));
1462 btrfs_set_device_bytes_used(leaf, dev_item,
1463 btrfs_device_get_bytes_used(device));
1464 btrfs_set_device_group(leaf, dev_item, 0);
1465 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1466 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1467 btrfs_set_device_start_offset(leaf, dev_item, 0);
1468
1469 ptr = btrfs_device_uuid(dev_item);
1470 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1471 ptr = btrfs_device_fsid(dev_item);
1472 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1473 btrfs_mark_buffer_dirty(leaf);
1474
1475 ret = 0;
1476 out:
1477 btrfs_free_path(path);
1478 return ret;
1479 }
1480
1481 /*
1482 * Function to update ctime/mtime for a given device path.
1483 * Mainly used for ctime/mtime based probe like libblkid.
1484 */
1485 static void update_dev_time(char *path_name)
1486 {
1487 struct file *filp;
1488
1489 filp = filp_open(path_name, O_RDWR, 0);
1490 if (IS_ERR(filp))
1491 return;
1492 file_update_time(filp);
1493 filp_close(filp, NULL);
1494 return;
1495 }
1496
1497 static int btrfs_rm_dev_item(struct btrfs_root *root,
1498 struct btrfs_device *device)
1499 {
1500 int ret;
1501 struct btrfs_path *path;
1502 struct btrfs_key key;
1503 struct btrfs_trans_handle *trans;
1504
1505 root = root->fs_info->chunk_root;
1506
1507 path = btrfs_alloc_path();
1508 if (!path)
1509 return -ENOMEM;
1510
1511 trans = btrfs_start_transaction(root, 0);
1512 if (IS_ERR(trans)) {
1513 btrfs_free_path(path);
1514 return PTR_ERR(trans);
1515 }
1516 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1517 key.type = BTRFS_DEV_ITEM_KEY;
1518 key.offset = device->devid;
1519
1520 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1521 if (ret < 0)
1522 goto out;
1523
1524 if (ret > 0) {
1525 ret = -ENOENT;
1526 goto out;
1527 }
1528
1529 ret = btrfs_del_item(trans, root, path);
1530 if (ret)
1531 goto out;
1532 out:
1533 btrfs_free_path(path);
1534 btrfs_commit_transaction(trans, root);
1535 return ret;
1536 }
1537
1538 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1539 {
1540 struct btrfs_device *device;
1541 struct btrfs_device *next_device;
1542 struct block_device *bdev;
1543 struct buffer_head *bh = NULL;
1544 struct btrfs_super_block *disk_super;
1545 struct btrfs_fs_devices *cur_devices;
1546 u64 all_avail;
1547 u64 devid;
1548 u64 num_devices;
1549 u8 *dev_uuid;
1550 unsigned seq;
1551 int ret = 0;
1552 bool clear_super = false;
1553
1554 mutex_lock(&uuid_mutex);
1555
1556 do {
1557 seq = read_seqbegin(&root->fs_info->profiles_lock);
1558
1559 all_avail = root->fs_info->avail_data_alloc_bits |
1560 root->fs_info->avail_system_alloc_bits |
1561 root->fs_info->avail_metadata_alloc_bits;
1562 } while (read_seqretry(&root->fs_info->profiles_lock, seq));
1563
1564 num_devices = root->fs_info->fs_devices->num_devices;
1565 btrfs_dev_replace_lock(&root->fs_info->dev_replace);
1566 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1567 WARN_ON(num_devices < 1);
1568 num_devices--;
1569 }
1570 btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
1571
1572 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
1573 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
1574 goto out;
1575 }
1576
1577 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
1578 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
1579 goto out;
1580 }
1581
1582 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
1583 root->fs_info->fs_devices->rw_devices <= 2) {
1584 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
1585 goto out;
1586 }
1587 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
1588 root->fs_info->fs_devices->rw_devices <= 3) {
1589 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
1590 goto out;
1591 }
1592
1593 if (strcmp(device_path, "missing") == 0) {
1594 struct list_head *devices;
1595 struct btrfs_device *tmp;
1596
1597 device = NULL;
1598 devices = &root->fs_info->fs_devices->devices;
1599 /*
1600 * It is safe to read the devices since the volume_mutex
1601 * is held.
1602 */
1603 list_for_each_entry(tmp, devices, dev_list) {
1604 if (tmp->in_fs_metadata &&
1605 !tmp->is_tgtdev_for_dev_replace &&
1606 !tmp->bdev) {
1607 device = tmp;
1608 break;
1609 }
1610 }
1611 bdev = NULL;
1612 bh = NULL;
1613 disk_super = NULL;
1614 if (!device) {
1615 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
1616 goto out;
1617 }
1618 } else {
1619 ret = btrfs_get_bdev_and_sb(device_path,
1620 FMODE_WRITE | FMODE_EXCL,
1621 root->fs_info->bdev_holder, 0,
1622 &bdev, &bh);
1623 if (ret)
1624 goto out;
1625 disk_super = (struct btrfs_super_block *)bh->b_data;
1626 devid = btrfs_stack_device_id(&disk_super->dev_item);
1627 dev_uuid = disk_super->dev_item.uuid;
1628 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1629 disk_super->fsid);
1630 if (!device) {
1631 ret = -ENOENT;
1632 goto error_brelse;
1633 }
1634 }
1635
1636 if (device->is_tgtdev_for_dev_replace) {
1637 ret = BTRFS_ERROR_DEV_TGT_REPLACE;
1638 goto error_brelse;
1639 }
1640
1641 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1642 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
1643 goto error_brelse;
1644 }
1645
1646 if (device->writeable) {
1647 lock_chunks(root);
1648 list_del_init(&device->dev_alloc_list);
1649 device->fs_devices->rw_devices--;
1650 unlock_chunks(root);
1651 clear_super = true;
1652 }
1653
1654 mutex_unlock(&uuid_mutex);
1655 ret = btrfs_shrink_device(device, 0);
1656 mutex_lock(&uuid_mutex);
1657 if (ret)
1658 goto error_undo;
1659
1660 /*
1661 * TODO: the superblock still includes this device in its num_devices
1662 * counter although write_all_supers() is not locked out. This
1663 * could give a filesystem state which requires a degraded mount.
1664 */
1665 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1666 if (ret)
1667 goto error_undo;
1668
1669 device->in_fs_metadata = 0;
1670 btrfs_scrub_cancel_dev(root->fs_info, device);
1671
1672 /*
1673 * the device list mutex makes sure that we don't change
1674 * the device list while someone else is writing out all
1675 * the device supers. Whoever is writing all supers, should
1676 * lock the device list mutex before getting the number of
1677 * devices in the super block (super_copy). Conversely,
1678 * whoever updates the number of devices in the super block
1679 * (super_copy) should hold the device list mutex.
1680 */
1681
1682 cur_devices = device->fs_devices;
1683 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1684 list_del_rcu(&device->dev_list);
1685
1686 device->fs_devices->num_devices--;
1687 device->fs_devices->total_devices--;
1688
1689 if (device->missing)
1690 device->fs_devices->missing_devices--;
1691
1692 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1693 struct btrfs_device, dev_list);
1694 if (device->bdev == root->fs_info->sb->s_bdev)
1695 root->fs_info->sb->s_bdev = next_device->bdev;
1696 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1697 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1698
1699 if (device->bdev) {
1700 device->fs_devices->open_devices--;
1701 /* remove sysfs entry */
1702 btrfs_kobj_rm_device(root->fs_info, device);
1703 }
1704
1705 call_rcu(&device->rcu, free_device);
1706
1707 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1708 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1709 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1710
1711 if (cur_devices->open_devices == 0) {
1712 struct btrfs_fs_devices *fs_devices;
1713 fs_devices = root->fs_info->fs_devices;
1714 while (fs_devices) {
1715 if (fs_devices->seed == cur_devices) {
1716 fs_devices->seed = cur_devices->seed;
1717 break;
1718 }
1719 fs_devices = fs_devices->seed;
1720 }
1721 cur_devices->seed = NULL;
1722 __btrfs_close_devices(cur_devices);
1723 free_fs_devices(cur_devices);
1724 }
1725
1726 root->fs_info->num_tolerated_disk_barrier_failures =
1727 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1728
1729 /*
1730 * at this point, the device is zero sized. We want to
1731 * remove it from the devices list and zero out the old super
1732 */
1733 if (clear_super && disk_super) {
1734 u64 bytenr;
1735 int i;
1736
1737 /* make sure this device isn't detected as part of
1738 * the FS anymore
1739 */
1740 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1741 set_buffer_dirty(bh);
1742 sync_dirty_buffer(bh);
1743
1744 /* clear the mirror copies of super block on the disk
1745 * being removed, 0th copy is been taken care above and
1746 * the below would take of the rest
1747 */
1748 for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1749 bytenr = btrfs_sb_offset(i);
1750 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
1751 i_size_read(bdev->bd_inode))
1752 break;
1753
1754 brelse(bh);
1755 bh = __bread(bdev, bytenr / 4096,
1756 BTRFS_SUPER_INFO_SIZE);
1757 if (!bh)
1758 continue;
1759
1760 disk_super = (struct btrfs_super_block *)bh->b_data;
1761
1762 if (btrfs_super_bytenr(disk_super) != bytenr ||
1763 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1764 continue;
1765 }
1766 memset(&disk_super->magic, 0,
1767 sizeof(disk_super->magic));
1768 set_buffer_dirty(bh);
1769 sync_dirty_buffer(bh);
1770 }
1771 }
1772
1773 ret = 0;
1774
1775 if (bdev) {
1776 /* Notify udev that device has changed */
1777 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
1778
1779 /* Update ctime/mtime for device path for libblkid */
1780 update_dev_time(device_path);
1781 }
1782
1783 error_brelse:
1784 brelse(bh);
1785 if (bdev)
1786 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1787 out:
1788 mutex_unlock(&uuid_mutex);
1789 return ret;
1790 error_undo:
1791 if (device->writeable) {
1792 lock_chunks(root);
1793 list_add(&device->dev_alloc_list,
1794 &root->fs_info->fs_devices->alloc_list);
1795 device->fs_devices->rw_devices++;
1796 unlock_chunks(root);
1797 }
1798 goto error_brelse;
1799 }
1800
1801 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
1802 struct btrfs_device *srcdev)
1803 {
1804 struct btrfs_fs_devices *fs_devices;
1805
1806 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1807
1808 /*
1809 * in case of fs with no seed, srcdev->fs_devices will point
1810 * to fs_devices of fs_info. However when the dev being replaced is
1811 * a seed dev it will point to the seed's local fs_devices. In short
1812 * srcdev will have its correct fs_devices in both the cases.
1813 */
1814 fs_devices = srcdev->fs_devices;
1815
1816 list_del_rcu(&srcdev->dev_list);
1817 list_del_rcu(&srcdev->dev_alloc_list);
1818 fs_devices->num_devices--;
1819 if (srcdev->missing)
1820 fs_devices->missing_devices--;
1821
1822 if (srcdev->writeable) {
1823 fs_devices->rw_devices--;
1824 /* zero out the old super if it is writable */
1825 btrfs_scratch_superblock(srcdev);
1826 }
1827
1828 if (srcdev->bdev)
1829 fs_devices->open_devices--;
1830 }
1831
1832 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
1833 struct btrfs_device *srcdev)
1834 {
1835 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
1836
1837 call_rcu(&srcdev->rcu, free_device);
1838
1839 /*
1840 * unless fs_devices is seed fs, num_devices shouldn't go
1841 * zero
1842 */
1843 BUG_ON(!fs_devices->num_devices && !fs_devices->seeding);
1844
1845 /* if this is no devs we rather delete the fs_devices */
1846 if (!fs_devices->num_devices) {
1847 struct btrfs_fs_devices *tmp_fs_devices;
1848
1849 tmp_fs_devices = fs_info->fs_devices;
1850 while (tmp_fs_devices) {
1851 if (tmp_fs_devices->seed == fs_devices) {
1852 tmp_fs_devices->seed = fs_devices->seed;
1853 break;
1854 }
1855 tmp_fs_devices = tmp_fs_devices->seed;
1856 }
1857 fs_devices->seed = NULL;
1858 __btrfs_close_devices(fs_devices);
1859 free_fs_devices(fs_devices);
1860 }
1861 }
1862
1863 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
1864 struct btrfs_device *tgtdev)
1865 {
1866 struct btrfs_device *next_device;
1867
1868 mutex_lock(&uuid_mutex);
1869 WARN_ON(!tgtdev);
1870 mutex_lock(&fs_info->fs_devices->device_list_mutex);
1871 if (tgtdev->bdev) {
1872 btrfs_scratch_superblock(tgtdev);
1873 fs_info->fs_devices->open_devices--;
1874 }
1875 fs_info->fs_devices->num_devices--;
1876
1877 next_device = list_entry(fs_info->fs_devices->devices.next,
1878 struct btrfs_device, dev_list);
1879 if (tgtdev->bdev == fs_info->sb->s_bdev)
1880 fs_info->sb->s_bdev = next_device->bdev;
1881 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
1882 fs_info->fs_devices->latest_bdev = next_device->bdev;
1883 list_del_rcu(&tgtdev->dev_list);
1884
1885 call_rcu(&tgtdev->rcu, free_device);
1886
1887 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
1888 mutex_unlock(&uuid_mutex);
1889 }
1890
1891 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
1892 struct btrfs_device **device)
1893 {
1894 int ret = 0;
1895 struct btrfs_super_block *disk_super;
1896 u64 devid;
1897 u8 *dev_uuid;
1898 struct block_device *bdev;
1899 struct buffer_head *bh;
1900
1901 *device = NULL;
1902 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ,
1903 root->fs_info->bdev_holder, 0, &bdev, &bh);
1904 if (ret)
1905 return ret;
1906 disk_super = (struct btrfs_super_block *)bh->b_data;
1907 devid = btrfs_stack_device_id(&disk_super->dev_item);
1908 dev_uuid = disk_super->dev_item.uuid;
1909 *device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1910 disk_super->fsid);
1911 brelse(bh);
1912 if (!*device)
1913 ret = -ENOENT;
1914 blkdev_put(bdev, FMODE_READ);
1915 return ret;
1916 }
1917
1918 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
1919 char *device_path,
1920 struct btrfs_device **device)
1921 {
1922 *device = NULL;
1923 if (strcmp(device_path, "missing") == 0) {
1924 struct list_head *devices;
1925 struct btrfs_device *tmp;
1926
1927 devices = &root->fs_info->fs_devices->devices;
1928 /*
1929 * It is safe to read the devices since the volume_mutex
1930 * is held by the caller.
1931 */
1932 list_for_each_entry(tmp, devices, dev_list) {
1933 if (tmp->in_fs_metadata && !tmp->bdev) {
1934 *device = tmp;
1935 break;
1936 }
1937 }
1938
1939 if (!*device) {
1940 btrfs_err(root->fs_info, "no missing device found");
1941 return -ENOENT;
1942 }
1943
1944 return 0;
1945 } else {
1946 return btrfs_find_device_by_path(root, device_path, device);
1947 }
1948 }
1949
1950 /*
1951 * does all the dirty work required for changing file system's UUID.
1952 */
1953 static int btrfs_prepare_sprout(struct btrfs_root *root)
1954 {
1955 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1956 struct btrfs_fs_devices *old_devices;
1957 struct btrfs_fs_devices *seed_devices;
1958 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
1959 struct btrfs_device *device;
1960 u64 super_flags;
1961
1962 BUG_ON(!mutex_is_locked(&uuid_mutex));
1963 if (!fs_devices->seeding)
1964 return -EINVAL;
1965
1966 seed_devices = __alloc_fs_devices();
1967 if (IS_ERR(seed_devices))
1968 return PTR_ERR(seed_devices);
1969
1970 old_devices = clone_fs_devices(fs_devices);
1971 if (IS_ERR(old_devices)) {
1972 kfree(seed_devices);
1973 return PTR_ERR(old_devices);
1974 }
1975
1976 list_add(&old_devices->list, &fs_uuids);
1977
1978 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1979 seed_devices->opened = 1;
1980 INIT_LIST_HEAD(&seed_devices->devices);
1981 INIT_LIST_HEAD(&seed_devices->alloc_list);
1982 mutex_init(&seed_devices->device_list_mutex);
1983
1984 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1985 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
1986 synchronize_rcu);
1987 list_for_each_entry(device, &seed_devices->devices, dev_list)
1988 device->fs_devices = seed_devices;
1989
1990 lock_chunks(root);
1991 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1992 unlock_chunks(root);
1993
1994 fs_devices->seeding = 0;
1995 fs_devices->num_devices = 0;
1996 fs_devices->open_devices = 0;
1997 fs_devices->missing_devices = 0;
1998 fs_devices->rotating = 0;
1999 fs_devices->seed = seed_devices;
2000
2001 generate_random_uuid(fs_devices->fsid);
2002 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2003 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2004 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2005
2006 super_flags = btrfs_super_flags(disk_super) &
2007 ~BTRFS_SUPER_FLAG_SEEDING;
2008 btrfs_set_super_flags(disk_super, super_flags);
2009
2010 return 0;
2011 }
2012
2013 /*
2014 * strore the expected generation for seed devices in device items.
2015 */
2016 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
2017 struct btrfs_root *root)
2018 {
2019 struct btrfs_path *path;
2020 struct extent_buffer *leaf;
2021 struct btrfs_dev_item *dev_item;
2022 struct btrfs_device *device;
2023 struct btrfs_key key;
2024 u8 fs_uuid[BTRFS_UUID_SIZE];
2025 u8 dev_uuid[BTRFS_UUID_SIZE];
2026 u64 devid;
2027 int ret;
2028
2029 path = btrfs_alloc_path();
2030 if (!path)
2031 return -ENOMEM;
2032
2033 root = root->fs_info->chunk_root;
2034 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2035 key.offset = 0;
2036 key.type = BTRFS_DEV_ITEM_KEY;
2037
2038 while (1) {
2039 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2040 if (ret < 0)
2041 goto error;
2042
2043 leaf = path->nodes[0];
2044 next_slot:
2045 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2046 ret = btrfs_next_leaf(root, path);
2047 if (ret > 0)
2048 break;
2049 if (ret < 0)
2050 goto error;
2051 leaf = path->nodes[0];
2052 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2053 btrfs_release_path(path);
2054 continue;
2055 }
2056
2057 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2058 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2059 key.type != BTRFS_DEV_ITEM_KEY)
2060 break;
2061
2062 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2063 struct btrfs_dev_item);
2064 devid = btrfs_device_id(leaf, dev_item);
2065 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2066 BTRFS_UUID_SIZE);
2067 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2068 BTRFS_UUID_SIZE);
2069 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2070 fs_uuid);
2071 BUG_ON(!device); /* Logic error */
2072
2073 if (device->fs_devices->seeding) {
2074 btrfs_set_device_generation(leaf, dev_item,
2075 device->generation);
2076 btrfs_mark_buffer_dirty(leaf);
2077 }
2078
2079 path->slots[0]++;
2080 goto next_slot;
2081 }
2082 ret = 0;
2083 error:
2084 btrfs_free_path(path);
2085 return ret;
2086 }
2087
2088 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
2089 {
2090 struct request_queue *q;
2091 struct btrfs_trans_handle *trans;
2092 struct btrfs_device *device;
2093 struct block_device *bdev;
2094 struct list_head *devices;
2095 struct super_block *sb = root->fs_info->sb;
2096 struct rcu_string *name;
2097 u64 tmp;
2098 int seeding_dev = 0;
2099 int ret = 0;
2100
2101 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
2102 return -EROFS;
2103
2104 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2105 root->fs_info->bdev_holder);
2106 if (IS_ERR(bdev))
2107 return PTR_ERR(bdev);
2108
2109 if (root->fs_info->fs_devices->seeding) {
2110 seeding_dev = 1;
2111 down_write(&sb->s_umount);
2112 mutex_lock(&uuid_mutex);
2113 }
2114
2115 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2116
2117 devices = &root->fs_info->fs_devices->devices;
2118
2119 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2120 list_for_each_entry(device, devices, dev_list) {
2121 if (device->bdev == bdev) {
2122 ret = -EEXIST;
2123 mutex_unlock(
2124 &root->fs_info->fs_devices->device_list_mutex);
2125 goto error;
2126 }
2127 }
2128 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2129
2130 device = btrfs_alloc_device(root->fs_info, NULL, NULL);
2131 if (IS_ERR(device)) {
2132 /* we can safely leave the fs_devices entry around */
2133 ret = PTR_ERR(device);
2134 goto error;
2135 }
2136
2137 name = rcu_string_strdup(device_path, GFP_NOFS);
2138 if (!name) {
2139 kfree(device);
2140 ret = -ENOMEM;
2141 goto error;
2142 }
2143 rcu_assign_pointer(device->name, name);
2144
2145 trans = btrfs_start_transaction(root, 0);
2146 if (IS_ERR(trans)) {
2147 rcu_string_free(device->name);
2148 kfree(device);
2149 ret = PTR_ERR(trans);
2150 goto error;
2151 }
2152
2153 q = bdev_get_queue(bdev);
2154 if (blk_queue_discard(q))
2155 device->can_discard = 1;
2156 device->writeable = 1;
2157 device->generation = trans->transid;
2158 device->io_width = root->sectorsize;
2159 device->io_align = root->sectorsize;
2160 device->sector_size = root->sectorsize;
2161 device->total_bytes = i_size_read(bdev->bd_inode);
2162 device->disk_total_bytes = device->total_bytes;
2163 device->commit_total_bytes = device->total_bytes;
2164 device->dev_root = root->fs_info->dev_root;
2165 device->bdev = bdev;
2166 device->in_fs_metadata = 1;
2167 device->is_tgtdev_for_dev_replace = 0;
2168 device->mode = FMODE_EXCL;
2169 device->dev_stats_valid = 1;
2170 set_blocksize(device->bdev, 4096);
2171
2172 if (seeding_dev) {
2173 sb->s_flags &= ~MS_RDONLY;
2174 ret = btrfs_prepare_sprout(root);
2175 BUG_ON(ret); /* -ENOMEM */
2176 }
2177
2178 device->fs_devices = root->fs_info->fs_devices;
2179
2180 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2181 lock_chunks(root);
2182 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
2183 list_add(&device->dev_alloc_list,
2184 &root->fs_info->fs_devices->alloc_list);
2185 root->fs_info->fs_devices->num_devices++;
2186 root->fs_info->fs_devices->open_devices++;
2187 root->fs_info->fs_devices->rw_devices++;
2188 root->fs_info->fs_devices->total_devices++;
2189 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
2190
2191 spin_lock(&root->fs_info->free_chunk_lock);
2192 root->fs_info->free_chunk_space += device->total_bytes;
2193 spin_unlock(&root->fs_info->free_chunk_lock);
2194
2195 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
2196 root->fs_info->fs_devices->rotating = 1;
2197
2198 tmp = btrfs_super_total_bytes(root->fs_info->super_copy);
2199 btrfs_set_super_total_bytes(root->fs_info->super_copy,
2200 tmp + device->total_bytes);
2201
2202 tmp = btrfs_super_num_devices(root->fs_info->super_copy);
2203 btrfs_set_super_num_devices(root->fs_info->super_copy,
2204 tmp + 1);
2205
2206 /* add sysfs device entry */
2207 btrfs_kobj_add_device(root->fs_info, device);
2208
2209 /*
2210 * we've got more storage, clear any full flags on the space
2211 * infos
2212 */
2213 btrfs_clear_space_info_full(root->fs_info);
2214
2215 unlock_chunks(root);
2216 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2217
2218 if (seeding_dev) {
2219 lock_chunks(root);
2220 ret = init_first_rw_device(trans, root, device);
2221 unlock_chunks(root);
2222 if (ret) {
2223 btrfs_abort_transaction(trans, root, ret);
2224 goto error_trans;
2225 }
2226 }
2227
2228 ret = btrfs_add_device(trans, root, device);
2229 if (ret) {
2230 btrfs_abort_transaction(trans, root, ret);
2231 goto error_trans;
2232 }
2233
2234 if (seeding_dev) {
2235 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2236
2237 ret = btrfs_finish_sprout(trans, root);
2238 if (ret) {
2239 btrfs_abort_transaction(trans, root, ret);
2240 goto error_trans;
2241 }
2242
2243 /* Sprouting would change fsid of the mounted root,
2244 * so rename the fsid on the sysfs
2245 */
2246 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU",
2247 root->fs_info->fsid);
2248 if (kobject_rename(&root->fs_info->super_kobj, fsid_buf))
2249 goto error_trans;
2250 }
2251
2252 root->fs_info->num_tolerated_disk_barrier_failures =
2253 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2254 ret = btrfs_commit_transaction(trans, root);
2255
2256 if (seeding_dev) {
2257 mutex_unlock(&uuid_mutex);
2258 up_write(&sb->s_umount);
2259
2260 if (ret) /* transaction commit */
2261 return ret;
2262
2263 ret = btrfs_relocate_sys_chunks(root);
2264 if (ret < 0)
2265 btrfs_error(root->fs_info, ret,
2266 "Failed to relocate sys chunks after "
2267 "device initialization. This can be fixed "
2268 "using the \"btrfs balance\" command.");
2269 trans = btrfs_attach_transaction(root);
2270 if (IS_ERR(trans)) {
2271 if (PTR_ERR(trans) == -ENOENT)
2272 return 0;
2273 return PTR_ERR(trans);
2274 }
2275 ret = btrfs_commit_transaction(trans, root);
2276 }
2277
2278 /* Update ctime/mtime for libblkid */
2279 update_dev_time(device_path);
2280 return ret;
2281
2282 error_trans:
2283 btrfs_end_transaction(trans, root);
2284 rcu_string_free(device->name);
2285 btrfs_kobj_rm_device(root->fs_info, device);
2286 kfree(device);
2287 error:
2288 blkdev_put(bdev, FMODE_EXCL);
2289 if (seeding_dev) {
2290 mutex_unlock(&uuid_mutex);
2291 up_write(&sb->s_umount);
2292 }
2293 return ret;
2294 }
2295
2296 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2297 struct btrfs_device *srcdev,
2298 struct btrfs_device **device_out)
2299 {
2300 struct request_queue *q;
2301 struct btrfs_device *device;
2302 struct block_device *bdev;
2303 struct btrfs_fs_info *fs_info = root->fs_info;
2304 struct list_head *devices;
2305 struct rcu_string *name;
2306 u64 devid = BTRFS_DEV_REPLACE_DEVID;
2307 int ret = 0;
2308
2309 *device_out = NULL;
2310 if (fs_info->fs_devices->seeding) {
2311 btrfs_err(fs_info, "the filesystem is a seed filesystem!");
2312 return -EINVAL;
2313 }
2314
2315 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2316 fs_info->bdev_holder);
2317 if (IS_ERR(bdev)) {
2318 btrfs_err(fs_info, "target device %s is invalid!", device_path);
2319 return PTR_ERR(bdev);
2320 }
2321
2322 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2323
2324 devices = &fs_info->fs_devices->devices;
2325 list_for_each_entry(device, devices, dev_list) {
2326 if (device->bdev == bdev) {
2327 btrfs_err(fs_info, "target device is in the filesystem!");
2328 ret = -EEXIST;
2329 goto error;
2330 }
2331 }
2332
2333
2334 if (i_size_read(bdev->bd_inode) <
2335 btrfs_device_get_total_bytes(srcdev)) {
2336 btrfs_err(fs_info, "target device is smaller than source device!");
2337 ret = -EINVAL;
2338 goto error;
2339 }
2340
2341
2342 device = btrfs_alloc_device(NULL, &devid, NULL);
2343 if (IS_ERR(device)) {
2344 ret = PTR_ERR(device);
2345 goto error;
2346 }
2347
2348 name = rcu_string_strdup(device_path, GFP_NOFS);
2349 if (!name) {
2350 kfree(device);
2351 ret = -ENOMEM;
2352 goto error;
2353 }
2354 rcu_assign_pointer(device->name, name);
2355
2356 q = bdev_get_queue(bdev);
2357 if (blk_queue_discard(q))
2358 device->can_discard = 1;
2359 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2360 device->writeable = 1;
2361 device->generation = 0;
2362 device->io_width = root->sectorsize;
2363 device->io_align = root->sectorsize;
2364 device->sector_size = root->sectorsize;
2365 device->total_bytes = btrfs_device_get_total_bytes(srcdev);
2366 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev);
2367 device->bytes_used = btrfs_device_get_bytes_used(srcdev);
2368 ASSERT(list_empty(&srcdev->resized_list));
2369 device->commit_total_bytes = srcdev->commit_total_bytes;
2370 device->commit_bytes_used = device->bytes_used;
2371 device->dev_root = fs_info->dev_root;
2372 device->bdev = bdev;
2373 device->in_fs_metadata = 1;
2374 device->is_tgtdev_for_dev_replace = 1;
2375 device->mode = FMODE_EXCL;
2376 device->dev_stats_valid = 1;
2377 set_blocksize(device->bdev, 4096);
2378 device->fs_devices = fs_info->fs_devices;
2379 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2380 fs_info->fs_devices->num_devices++;
2381 fs_info->fs_devices->open_devices++;
2382 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2383
2384 *device_out = device;
2385 return ret;
2386
2387 error:
2388 blkdev_put(bdev, FMODE_EXCL);
2389 return ret;
2390 }
2391
2392 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2393 struct btrfs_device *tgtdev)
2394 {
2395 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2396 tgtdev->io_width = fs_info->dev_root->sectorsize;
2397 tgtdev->io_align = fs_info->dev_root->sectorsize;
2398 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2399 tgtdev->dev_root = fs_info->dev_root;
2400 tgtdev->in_fs_metadata = 1;
2401 }
2402
2403 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2404 struct btrfs_device *device)
2405 {
2406 int ret;
2407 struct btrfs_path *path;
2408 struct btrfs_root *root;
2409 struct btrfs_dev_item *dev_item;
2410 struct extent_buffer *leaf;
2411 struct btrfs_key key;
2412
2413 root = device->dev_root->fs_info->chunk_root;
2414
2415 path = btrfs_alloc_path();
2416 if (!path)
2417 return -ENOMEM;
2418
2419 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2420 key.type = BTRFS_DEV_ITEM_KEY;
2421 key.offset = device->devid;
2422
2423 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2424 if (ret < 0)
2425 goto out;
2426
2427 if (ret > 0) {
2428 ret = -ENOENT;
2429 goto out;
2430 }
2431
2432 leaf = path->nodes[0];
2433 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2434
2435 btrfs_set_device_id(leaf, dev_item, device->devid);
2436 btrfs_set_device_type(leaf, dev_item, device->type);
2437 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2438 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2439 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2440 btrfs_set_device_total_bytes(leaf, dev_item,
2441 btrfs_device_get_disk_total_bytes(device));
2442 btrfs_set_device_bytes_used(leaf, dev_item,
2443 btrfs_device_get_bytes_used(device));
2444 btrfs_mark_buffer_dirty(leaf);
2445
2446 out:
2447 btrfs_free_path(path);
2448 return ret;
2449 }
2450
2451 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2452 struct btrfs_device *device, u64 new_size)
2453 {
2454 struct btrfs_super_block *super_copy =
2455 device->dev_root->fs_info->super_copy;
2456 struct btrfs_fs_devices *fs_devices;
2457 u64 old_total;
2458 u64 diff;
2459
2460 if (!device->writeable)
2461 return -EACCES;
2462
2463 lock_chunks(device->dev_root);
2464 old_total = btrfs_super_total_bytes(super_copy);
2465 diff = new_size - device->total_bytes;
2466
2467 if (new_size <= device->total_bytes ||
2468 device->is_tgtdev_for_dev_replace) {
2469 unlock_chunks(device->dev_root);
2470 return -EINVAL;
2471 }
2472
2473 fs_devices = device->dev_root->fs_info->fs_devices;
2474
2475 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2476 device->fs_devices->total_rw_bytes += diff;
2477
2478 btrfs_device_set_total_bytes(device, new_size);
2479 btrfs_device_set_disk_total_bytes(device, new_size);
2480 btrfs_clear_space_info_full(device->dev_root->fs_info);
2481 if (list_empty(&device->resized_list))
2482 list_add_tail(&device->resized_list,
2483 &fs_devices->resized_devices);
2484 unlock_chunks(device->dev_root);
2485
2486 return btrfs_update_device(trans, device);
2487 }
2488
2489 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2490 struct btrfs_root *root,
2491 u64 chunk_tree, u64 chunk_objectid,
2492 u64 chunk_offset)
2493 {
2494 int ret;
2495 struct btrfs_path *path;
2496 struct btrfs_key key;
2497
2498 root = root->fs_info->chunk_root;
2499 path = btrfs_alloc_path();
2500 if (!path)
2501 return -ENOMEM;
2502
2503 key.objectid = chunk_objectid;
2504 key.offset = chunk_offset;
2505 key.type = BTRFS_CHUNK_ITEM_KEY;
2506
2507 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2508 if (ret < 0)
2509 goto out;
2510 else if (ret > 0) { /* Logic error or corruption */
2511 btrfs_error(root->fs_info, -ENOENT,
2512 "Failed lookup while freeing chunk.");
2513 ret = -ENOENT;
2514 goto out;
2515 }
2516
2517 ret = btrfs_del_item(trans, root, path);
2518 if (ret < 0)
2519 btrfs_error(root->fs_info, ret,
2520 "Failed to delete chunk item.");
2521 out:
2522 btrfs_free_path(path);
2523 return ret;
2524 }
2525
2526 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2527 chunk_offset)
2528 {
2529 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2530 struct btrfs_disk_key *disk_key;
2531 struct btrfs_chunk *chunk;
2532 u8 *ptr;
2533 int ret = 0;
2534 u32 num_stripes;
2535 u32 array_size;
2536 u32 len = 0;
2537 u32 cur;
2538 struct btrfs_key key;
2539
2540 lock_chunks(root);
2541 array_size = btrfs_super_sys_array_size(super_copy);
2542
2543 ptr = super_copy->sys_chunk_array;
2544 cur = 0;
2545
2546 while (cur < array_size) {
2547 disk_key = (struct btrfs_disk_key *)ptr;
2548 btrfs_disk_key_to_cpu(&key, disk_key);
2549
2550 len = sizeof(*disk_key);
2551
2552 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2553 chunk = (struct btrfs_chunk *)(ptr + len);
2554 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2555 len += btrfs_chunk_item_size(num_stripes);
2556 } else {
2557 ret = -EIO;
2558 break;
2559 }
2560 if (key.objectid == chunk_objectid &&
2561 key.offset == chunk_offset) {
2562 memmove(ptr, ptr + len, array_size - (cur + len));
2563 array_size -= len;
2564 btrfs_set_super_sys_array_size(super_copy, array_size);
2565 } else {
2566 ptr += len;
2567 cur += len;
2568 }
2569 }
2570 unlock_chunks(root);
2571 return ret;
2572 }
2573
2574 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
2575 struct btrfs_root *root, u64 chunk_offset)
2576 {
2577 struct extent_map_tree *em_tree;
2578 struct extent_map *em;
2579 struct btrfs_root *extent_root = root->fs_info->extent_root;
2580 struct map_lookup *map;
2581 u64 dev_extent_len = 0;
2582 u64 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2583 u64 chunk_tree = root->fs_info->chunk_root->objectid;
2584 int i, ret = 0;
2585
2586 /* Just in case */
2587 root = root->fs_info->chunk_root;
2588 em_tree = &root->fs_info->mapping_tree.map_tree;
2589
2590 read_lock(&em_tree->lock);
2591 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2592 read_unlock(&em_tree->lock);
2593
2594 if (!em || em->start > chunk_offset ||
2595 em->start + em->len < chunk_offset) {
2596 /*
2597 * This is a logic error, but we don't want to just rely on the
2598 * user having built with ASSERT enabled, so if ASSERT doens't
2599 * do anything we still error out.
2600 */
2601 ASSERT(0);
2602 if (em)
2603 free_extent_map(em);
2604 return -EINVAL;
2605 }
2606 map = (struct map_lookup *)em->bdev;
2607
2608 for (i = 0; i < map->num_stripes; i++) {
2609 struct btrfs_device *device = map->stripes[i].dev;
2610 ret = btrfs_free_dev_extent(trans, device,
2611 map->stripes[i].physical,
2612 &dev_extent_len);
2613 if (ret) {
2614 btrfs_abort_transaction(trans, root, ret);
2615 goto out;
2616 }
2617
2618 if (device->bytes_used > 0) {
2619 lock_chunks(root);
2620 btrfs_device_set_bytes_used(device,
2621 device->bytes_used - dev_extent_len);
2622 spin_lock(&root->fs_info->free_chunk_lock);
2623 root->fs_info->free_chunk_space += dev_extent_len;
2624 spin_unlock(&root->fs_info->free_chunk_lock);
2625 btrfs_clear_space_info_full(root->fs_info);
2626 unlock_chunks(root);
2627 }
2628
2629 if (map->stripes[i].dev) {
2630 ret = btrfs_update_device(trans, map->stripes[i].dev);
2631 if (ret) {
2632 btrfs_abort_transaction(trans, root, ret);
2633 goto out;
2634 }
2635 }
2636 }
2637 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
2638 chunk_offset);
2639 if (ret) {
2640 btrfs_abort_transaction(trans, root, ret);
2641 goto out;
2642 }
2643
2644 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2645
2646 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2647 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2648 if (ret) {
2649 btrfs_abort_transaction(trans, root, ret);
2650 goto out;
2651 }
2652 }
2653
2654 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset, em);
2655 if (ret) {
2656 btrfs_abort_transaction(trans, extent_root, ret);
2657 goto out;
2658 }
2659
2660 out:
2661 /* once for us */
2662 free_extent_map(em);
2663 return ret;
2664 }
2665
2666 static int btrfs_relocate_chunk(struct btrfs_root *root,
2667 u64 chunk_tree, u64 chunk_objectid,
2668 u64 chunk_offset)
2669 {
2670 struct btrfs_root *extent_root;
2671 struct btrfs_trans_handle *trans;
2672 int ret;
2673
2674 root = root->fs_info->chunk_root;
2675 extent_root = root->fs_info->extent_root;
2676
2677 ret = btrfs_can_relocate(extent_root, chunk_offset);
2678 if (ret)
2679 return -ENOSPC;
2680
2681 /* step one, relocate all the extents inside this chunk */
2682 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2683 if (ret)
2684 return ret;
2685
2686 trans = btrfs_start_transaction(root, 0);
2687 if (IS_ERR(trans)) {
2688 ret = PTR_ERR(trans);
2689 btrfs_std_error(root->fs_info, ret);
2690 return ret;
2691 }
2692
2693 /*
2694 * step two, delete the device extents and the
2695 * chunk tree entries
2696 */
2697 ret = btrfs_remove_chunk(trans, root, chunk_offset);
2698 btrfs_end_transaction(trans, root);
2699 return ret;
2700 }
2701
2702 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2703 {
2704 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2705 struct btrfs_path *path;
2706 struct extent_buffer *leaf;
2707 struct btrfs_chunk *chunk;
2708 struct btrfs_key key;
2709 struct btrfs_key found_key;
2710 u64 chunk_tree = chunk_root->root_key.objectid;
2711 u64 chunk_type;
2712 bool retried = false;
2713 int failed = 0;
2714 int ret;
2715
2716 path = btrfs_alloc_path();
2717 if (!path)
2718 return -ENOMEM;
2719
2720 again:
2721 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2722 key.offset = (u64)-1;
2723 key.type = BTRFS_CHUNK_ITEM_KEY;
2724
2725 while (1) {
2726 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2727 if (ret < 0)
2728 goto error;
2729 BUG_ON(ret == 0); /* Corruption */
2730
2731 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2732 key.type);
2733 if (ret < 0)
2734 goto error;
2735 if (ret > 0)
2736 break;
2737
2738 leaf = path->nodes[0];
2739 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2740
2741 chunk = btrfs_item_ptr(leaf, path->slots[0],
2742 struct btrfs_chunk);
2743 chunk_type = btrfs_chunk_type(leaf, chunk);
2744 btrfs_release_path(path);
2745
2746 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2747 ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
2748 found_key.objectid,
2749 found_key.offset);
2750 if (ret == -ENOSPC)
2751 failed++;
2752 else
2753 BUG_ON(ret);
2754 }
2755
2756 if (found_key.offset == 0)
2757 break;
2758 key.offset = found_key.offset - 1;
2759 }
2760 ret = 0;
2761 if (failed && !retried) {
2762 failed = 0;
2763 retried = true;
2764 goto again;
2765 } else if (WARN_ON(failed && retried)) {
2766 ret = -ENOSPC;
2767 }
2768 error:
2769 btrfs_free_path(path);
2770 return ret;
2771 }
2772
2773 static int insert_balance_item(struct btrfs_root *root,
2774 struct btrfs_balance_control *bctl)
2775 {
2776 struct btrfs_trans_handle *trans;
2777 struct btrfs_balance_item *item;
2778 struct btrfs_disk_balance_args disk_bargs;
2779 struct btrfs_path *path;
2780 struct extent_buffer *leaf;
2781 struct btrfs_key key;
2782 int ret, err;
2783
2784 path = btrfs_alloc_path();
2785 if (!path)
2786 return -ENOMEM;
2787
2788 trans = btrfs_start_transaction(root, 0);
2789 if (IS_ERR(trans)) {
2790 btrfs_free_path(path);
2791 return PTR_ERR(trans);
2792 }
2793
2794 key.objectid = BTRFS_BALANCE_OBJECTID;
2795 key.type = BTRFS_BALANCE_ITEM_KEY;
2796 key.offset = 0;
2797
2798 ret = btrfs_insert_empty_item(trans, root, path, &key,
2799 sizeof(*item));
2800 if (ret)
2801 goto out;
2802
2803 leaf = path->nodes[0];
2804 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2805
2806 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2807
2808 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2809 btrfs_set_balance_data(leaf, item, &disk_bargs);
2810 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2811 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2812 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2813 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2814
2815 btrfs_set_balance_flags(leaf, item, bctl->flags);
2816
2817 btrfs_mark_buffer_dirty(leaf);
2818 out:
2819 btrfs_free_path(path);
2820 err = btrfs_commit_transaction(trans, root);
2821 if (err && !ret)
2822 ret = err;
2823 return ret;
2824 }
2825
2826 static int del_balance_item(struct btrfs_root *root)
2827 {
2828 struct btrfs_trans_handle *trans;
2829 struct btrfs_path *path;
2830 struct btrfs_key key;
2831 int ret, err;
2832
2833 path = btrfs_alloc_path();
2834 if (!path)
2835 return -ENOMEM;
2836
2837 trans = btrfs_start_transaction(root, 0);
2838 if (IS_ERR(trans)) {
2839 btrfs_free_path(path);
2840 return PTR_ERR(trans);
2841 }
2842
2843 key.objectid = BTRFS_BALANCE_OBJECTID;
2844 key.type = BTRFS_BALANCE_ITEM_KEY;
2845 key.offset = 0;
2846
2847 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2848 if (ret < 0)
2849 goto out;
2850 if (ret > 0) {
2851 ret = -ENOENT;
2852 goto out;
2853 }
2854
2855 ret = btrfs_del_item(trans, root, path);
2856 out:
2857 btrfs_free_path(path);
2858 err = btrfs_commit_transaction(trans, root);
2859 if (err && !ret)
2860 ret = err;
2861 return ret;
2862 }
2863
2864 /*
2865 * This is a heuristic used to reduce the number of chunks balanced on
2866 * resume after balance was interrupted.
2867 */
2868 static void update_balance_args(struct btrfs_balance_control *bctl)
2869 {
2870 /*
2871 * Turn on soft mode for chunk types that were being converted.
2872 */
2873 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
2874 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
2875 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
2876 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
2877 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
2878 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
2879
2880 /*
2881 * Turn on usage filter if is not already used. The idea is
2882 * that chunks that we have already balanced should be
2883 * reasonably full. Don't do it for chunks that are being
2884 * converted - that will keep us from relocating unconverted
2885 * (albeit full) chunks.
2886 */
2887 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2888 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2889 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
2890 bctl->data.usage = 90;
2891 }
2892 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2893 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2894 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
2895 bctl->sys.usage = 90;
2896 }
2897 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2898 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2899 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
2900 bctl->meta.usage = 90;
2901 }
2902 }
2903
2904 /*
2905 * Should be called with both balance and volume mutexes held to
2906 * serialize other volume operations (add_dev/rm_dev/resize) with
2907 * restriper. Same goes for unset_balance_control.
2908 */
2909 static void set_balance_control(struct btrfs_balance_control *bctl)
2910 {
2911 struct btrfs_fs_info *fs_info = bctl->fs_info;
2912
2913 BUG_ON(fs_info->balance_ctl);
2914
2915 spin_lock(&fs_info->balance_lock);
2916 fs_info->balance_ctl = bctl;
2917 spin_unlock(&fs_info->balance_lock);
2918 }
2919
2920 static void unset_balance_control(struct btrfs_fs_info *fs_info)
2921 {
2922 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
2923
2924 BUG_ON(!fs_info->balance_ctl);
2925
2926 spin_lock(&fs_info->balance_lock);
2927 fs_info->balance_ctl = NULL;
2928 spin_unlock(&fs_info->balance_lock);
2929
2930 kfree(bctl);
2931 }
2932
2933 /*
2934 * Balance filters. Return 1 if chunk should be filtered out
2935 * (should not be balanced).
2936 */
2937 static int chunk_profiles_filter(u64 chunk_type,
2938 struct btrfs_balance_args *bargs)
2939 {
2940 chunk_type = chunk_to_extended(chunk_type) &
2941 BTRFS_EXTENDED_PROFILE_MASK;
2942
2943 if (bargs->profiles & chunk_type)
2944 return 0;
2945
2946 return 1;
2947 }
2948
2949 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
2950 struct btrfs_balance_args *bargs)
2951 {
2952 struct btrfs_block_group_cache *cache;
2953 u64 chunk_used, user_thresh;
2954 int ret = 1;
2955
2956 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2957 chunk_used = btrfs_block_group_used(&cache->item);
2958
2959 if (bargs->usage == 0)
2960 user_thresh = 1;
2961 else if (bargs->usage > 100)
2962 user_thresh = cache->key.offset;
2963 else
2964 user_thresh = div_factor_fine(cache->key.offset,
2965 bargs->usage);
2966
2967 if (chunk_used < user_thresh)
2968 ret = 0;
2969
2970 btrfs_put_block_group(cache);
2971 return ret;
2972 }
2973
2974 static int chunk_devid_filter(struct extent_buffer *leaf,
2975 struct btrfs_chunk *chunk,
2976 struct btrfs_balance_args *bargs)
2977 {
2978 struct btrfs_stripe *stripe;
2979 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2980 int i;
2981
2982 for (i = 0; i < num_stripes; i++) {
2983 stripe = btrfs_stripe_nr(chunk, i);
2984 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
2985 return 0;
2986 }
2987
2988 return 1;
2989 }
2990
2991 /* [pstart, pend) */
2992 static int chunk_drange_filter(struct extent_buffer *leaf,
2993 struct btrfs_chunk *chunk,
2994 u64 chunk_offset,
2995 struct btrfs_balance_args *bargs)
2996 {
2997 struct btrfs_stripe *stripe;
2998 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2999 u64 stripe_offset;
3000 u64 stripe_length;
3001 int factor;
3002 int i;
3003
3004 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3005 return 0;
3006
3007 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
3008 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
3009 factor = num_stripes / 2;
3010 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
3011 factor = num_stripes - 1;
3012 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
3013 factor = num_stripes - 2;
3014 } else {
3015 factor = num_stripes;
3016 }
3017
3018 for (i = 0; i < num_stripes; i++) {
3019 stripe = btrfs_stripe_nr(chunk, i);
3020 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3021 continue;
3022
3023 stripe_offset = btrfs_stripe_offset(leaf, stripe);
3024 stripe_length = btrfs_chunk_length(leaf, chunk);
3025 do_div(stripe_length, factor);
3026
3027 if (stripe_offset < bargs->pend &&
3028 stripe_offset + stripe_length > bargs->pstart)
3029 return 0;
3030 }
3031
3032 return 1;
3033 }
3034
3035 /* [vstart, vend) */
3036 static int chunk_vrange_filter(struct extent_buffer *leaf,
3037 struct btrfs_chunk *chunk,
3038 u64 chunk_offset,
3039 struct btrfs_balance_args *bargs)
3040 {
3041 if (chunk_offset < bargs->vend &&
3042 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
3043 /* at least part of the chunk is inside this vrange */
3044 return 0;
3045
3046 return 1;
3047 }
3048
3049 static int chunk_soft_convert_filter(u64 chunk_type,
3050 struct btrfs_balance_args *bargs)
3051 {
3052 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
3053 return 0;
3054
3055 chunk_type = chunk_to_extended(chunk_type) &
3056 BTRFS_EXTENDED_PROFILE_MASK;
3057
3058 if (bargs->target == chunk_type)
3059 return 1;
3060
3061 return 0;
3062 }
3063
3064 static int should_balance_chunk(struct btrfs_root *root,
3065 struct extent_buffer *leaf,
3066 struct btrfs_chunk *chunk, u64 chunk_offset)
3067 {
3068 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
3069 struct btrfs_balance_args *bargs = NULL;
3070 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
3071
3072 /* type filter */
3073 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
3074 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
3075 return 0;
3076 }
3077
3078 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3079 bargs = &bctl->data;
3080 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3081 bargs = &bctl->sys;
3082 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3083 bargs = &bctl->meta;
3084
3085 /* profiles filter */
3086 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
3087 chunk_profiles_filter(chunk_type, bargs)) {
3088 return 0;
3089 }
3090
3091 /* usage filter */
3092 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
3093 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
3094 return 0;
3095 }
3096
3097 /* devid filter */
3098 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
3099 chunk_devid_filter(leaf, chunk, bargs)) {
3100 return 0;
3101 }
3102
3103 /* drange filter, makes sense only with devid filter */
3104 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
3105 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
3106 return 0;
3107 }
3108
3109 /* vrange filter */
3110 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
3111 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
3112 return 0;
3113 }
3114
3115 /* soft profile changing mode */
3116 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
3117 chunk_soft_convert_filter(chunk_type, bargs)) {
3118 return 0;
3119 }
3120
3121 /*
3122 * limited by count, must be the last filter
3123 */
3124 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
3125 if (bargs->limit == 0)
3126 return 0;
3127 else
3128 bargs->limit--;
3129 }
3130
3131 return 1;
3132 }
3133
3134 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
3135 {
3136 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3137 struct btrfs_root *chunk_root = fs_info->chunk_root;
3138 struct btrfs_root *dev_root = fs_info->dev_root;
3139 struct list_head *devices;
3140 struct btrfs_device *device;
3141 u64 old_size;
3142 u64 size_to_free;
3143 struct btrfs_chunk *chunk;
3144 struct btrfs_path *path;
3145 struct btrfs_key key;
3146 struct btrfs_key found_key;
3147 struct btrfs_trans_handle *trans;
3148 struct extent_buffer *leaf;
3149 int slot;
3150 int ret;
3151 int enospc_errors = 0;
3152 bool counting = true;
3153 u64 limit_data = bctl->data.limit;
3154 u64 limit_meta = bctl->meta.limit;
3155 u64 limit_sys = bctl->sys.limit;
3156
3157 /* step one make some room on all the devices */
3158 devices = &fs_info->fs_devices->devices;
3159 list_for_each_entry(device, devices, dev_list) {
3160 old_size = btrfs_device_get_total_bytes(device);
3161 size_to_free = div_factor(old_size, 1);
3162 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
3163 if (!device->writeable ||
3164 btrfs_device_get_total_bytes(device) -
3165 btrfs_device_get_bytes_used(device) > size_to_free ||
3166 device->is_tgtdev_for_dev_replace)
3167 continue;
3168
3169 ret = btrfs_shrink_device(device, old_size - size_to_free);
3170 if (ret == -ENOSPC)
3171 break;
3172 BUG_ON(ret);
3173
3174 trans = btrfs_start_transaction(dev_root, 0);
3175 BUG_ON(IS_ERR(trans));
3176
3177 ret = btrfs_grow_device(trans, device, old_size);
3178 BUG_ON(ret);
3179
3180 btrfs_end_transaction(trans, dev_root);
3181 }
3182
3183 /* step two, relocate all the chunks */
3184 path = btrfs_alloc_path();
3185 if (!path) {
3186 ret = -ENOMEM;
3187 goto error;
3188 }
3189
3190 /* zero out stat counters */
3191 spin_lock(&fs_info->balance_lock);
3192 memset(&bctl->stat, 0, sizeof(bctl->stat));
3193 spin_unlock(&fs_info->balance_lock);
3194 again:
3195 if (!counting) {
3196 bctl->data.limit = limit_data;
3197 bctl->meta.limit = limit_meta;
3198 bctl->sys.limit = limit_sys;
3199 }
3200 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3201 key.offset = (u64)-1;
3202 key.type = BTRFS_CHUNK_ITEM_KEY;
3203
3204 while (1) {
3205 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
3206 atomic_read(&fs_info->balance_cancel_req)) {
3207 ret = -ECANCELED;
3208 goto error;
3209 }
3210
3211 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3212 if (ret < 0)
3213 goto error;
3214
3215 /*
3216 * this shouldn't happen, it means the last relocate
3217 * failed
3218 */
3219 if (ret == 0)
3220 BUG(); /* FIXME break ? */
3221
3222 ret = btrfs_previous_item(chunk_root, path, 0,
3223 BTRFS_CHUNK_ITEM_KEY);
3224 if (ret) {
3225 ret = 0;
3226 break;
3227 }
3228
3229 leaf = path->nodes[0];
3230 slot = path->slots[0];
3231 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3232
3233 if (found_key.objectid != key.objectid)
3234 break;
3235
3236 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3237
3238 if (!counting) {
3239 spin_lock(&fs_info->balance_lock);
3240 bctl->stat.considered++;
3241 spin_unlock(&fs_info->balance_lock);
3242 }
3243
3244 ret = should_balance_chunk(chunk_root, leaf, chunk,
3245 found_key.offset);
3246 btrfs_release_path(path);
3247 if (!ret)
3248 goto loop;
3249
3250 if (counting) {
3251 spin_lock(&fs_info->balance_lock);
3252 bctl->stat.expected++;
3253 spin_unlock(&fs_info->balance_lock);
3254 goto loop;
3255 }
3256
3257 ret = btrfs_relocate_chunk(chunk_root,
3258 chunk_root->root_key.objectid,
3259 found_key.objectid,
3260 found_key.offset);
3261 if (ret && ret != -ENOSPC)
3262 goto error;
3263 if (ret == -ENOSPC) {
3264 enospc_errors++;
3265 } else {
3266 spin_lock(&fs_info->balance_lock);
3267 bctl->stat.completed++;
3268 spin_unlock(&fs_info->balance_lock);
3269 }
3270 loop:
3271 if (found_key.offset == 0)
3272 break;
3273 key.offset = found_key.offset - 1;
3274 }
3275
3276 if (counting) {
3277 btrfs_release_path(path);
3278 counting = false;
3279 goto again;
3280 }
3281 error:
3282 btrfs_free_path(path);
3283 if (enospc_errors) {
3284 btrfs_info(fs_info, "%d enospc errors during balance",
3285 enospc_errors);
3286 if (!ret)
3287 ret = -ENOSPC;
3288 }
3289
3290 return ret;
3291 }
3292
3293 /**
3294 * alloc_profile_is_valid - see if a given profile is valid and reduced
3295 * @flags: profile to validate
3296 * @extended: if true @flags is treated as an extended profile
3297 */
3298 static int alloc_profile_is_valid(u64 flags, int extended)
3299 {
3300 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
3301 BTRFS_BLOCK_GROUP_PROFILE_MASK);
3302
3303 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
3304
3305 /* 1) check that all other bits are zeroed */
3306 if (flags & ~mask)
3307 return 0;
3308
3309 /* 2) see if profile is reduced */
3310 if (flags == 0)
3311 return !extended; /* "0" is valid for usual profiles */
3312
3313 /* true if exactly one bit set */
3314 return (flags & (flags - 1)) == 0;
3315 }
3316
3317 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
3318 {
3319 /* cancel requested || normal exit path */
3320 return atomic_read(&fs_info->balance_cancel_req) ||
3321 (atomic_read(&fs_info->balance_pause_req) == 0 &&
3322 atomic_read(&fs_info->balance_cancel_req) == 0);
3323 }
3324
3325 static void __cancel_balance(struct btrfs_fs_info *fs_info)
3326 {
3327 int ret;
3328
3329 unset_balance_control(fs_info);
3330 ret = del_balance_item(fs_info->tree_root);
3331 if (ret)
3332 btrfs_std_error(fs_info, ret);
3333
3334 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3335 }
3336
3337 /*
3338 * Should be called with both balance and volume mutexes held
3339 */
3340 int btrfs_balance(struct btrfs_balance_control *bctl,
3341 struct btrfs_ioctl_balance_args *bargs)
3342 {
3343 struct btrfs_fs_info *fs_info = bctl->fs_info;
3344 u64 allowed;
3345 int mixed = 0;
3346 int ret;
3347 u64 num_devices;
3348 unsigned seq;
3349
3350 if (btrfs_fs_closing(fs_info) ||
3351 atomic_read(&fs_info->balance_pause_req) ||
3352 atomic_read(&fs_info->balance_cancel_req)) {
3353 ret = -EINVAL;
3354 goto out;
3355 }
3356
3357 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3358 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3359 mixed = 1;
3360
3361 /*
3362 * In case of mixed groups both data and meta should be picked,
3363 * and identical options should be given for both of them.
3364 */
3365 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3366 if (mixed && (bctl->flags & allowed)) {
3367 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3368 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3369 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3370 btrfs_err(fs_info, "with mixed groups data and "
3371 "metadata balance options must be the same");
3372 ret = -EINVAL;
3373 goto out;
3374 }
3375 }
3376
3377 num_devices = fs_info->fs_devices->num_devices;
3378 btrfs_dev_replace_lock(&fs_info->dev_replace);
3379 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3380 BUG_ON(num_devices < 1);
3381 num_devices--;
3382 }
3383 btrfs_dev_replace_unlock(&fs_info->dev_replace);
3384 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3385 if (num_devices == 1)
3386 allowed |= BTRFS_BLOCK_GROUP_DUP;
3387 else if (num_devices > 1)
3388 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3389 if (num_devices > 2)
3390 allowed |= BTRFS_BLOCK_GROUP_RAID5;
3391 if (num_devices > 3)
3392 allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
3393 BTRFS_BLOCK_GROUP_RAID6);
3394 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3395 (!alloc_profile_is_valid(bctl->data.target, 1) ||
3396 (bctl->data.target & ~allowed))) {
3397 btrfs_err(fs_info, "unable to start balance with target "
3398 "data profile %llu",
3399 bctl->data.target);
3400 ret = -EINVAL;
3401 goto out;
3402 }
3403 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3404 (!alloc_profile_is_valid(bctl->meta.target, 1) ||
3405 (bctl->meta.target & ~allowed))) {
3406 btrfs_err(fs_info,
3407 "unable to start balance with target metadata profile %llu",
3408 bctl->meta.target);
3409 ret = -EINVAL;
3410 goto out;
3411 }
3412 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3413 (!alloc_profile_is_valid(bctl->sys.target, 1) ||
3414 (bctl->sys.target & ~allowed))) {
3415 btrfs_err(fs_info,
3416 "unable to start balance with target system profile %llu",
3417 bctl->sys.target);
3418 ret = -EINVAL;
3419 goto out;
3420 }
3421
3422 /* allow dup'ed data chunks only in mixed mode */
3423 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3424 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
3425 btrfs_err(fs_info, "dup for data is not allowed");
3426 ret = -EINVAL;
3427 goto out;
3428 }
3429
3430 /* allow to reduce meta or sys integrity only if force set */
3431 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3432 BTRFS_BLOCK_GROUP_RAID10 |
3433 BTRFS_BLOCK_GROUP_RAID5 |
3434 BTRFS_BLOCK_GROUP_RAID6;
3435 do {
3436 seq = read_seqbegin(&fs_info->profiles_lock);
3437
3438 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3439 (fs_info->avail_system_alloc_bits & allowed) &&
3440 !(bctl->sys.target & allowed)) ||
3441 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3442 (fs_info->avail_metadata_alloc_bits & allowed) &&
3443 !(bctl->meta.target & allowed))) {
3444 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3445 btrfs_info(fs_info, "force reducing metadata integrity");
3446 } else {
3447 btrfs_err(fs_info, "balance will reduce metadata "
3448 "integrity, use force if you want this");
3449 ret = -EINVAL;
3450 goto out;
3451 }
3452 }
3453 } while (read_seqretry(&fs_info->profiles_lock, seq));
3454
3455 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3456 int num_tolerated_disk_barrier_failures;
3457 u64 target = bctl->sys.target;
3458
3459 num_tolerated_disk_barrier_failures =
3460 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3461 if (num_tolerated_disk_barrier_failures > 0 &&
3462 (target &
3463 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 |
3464 BTRFS_AVAIL_ALLOC_BIT_SINGLE)))
3465 num_tolerated_disk_barrier_failures = 0;
3466 else if (num_tolerated_disk_barrier_failures > 1 &&
3467 (target &
3468 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)))
3469 num_tolerated_disk_barrier_failures = 1;
3470
3471 fs_info->num_tolerated_disk_barrier_failures =
3472 num_tolerated_disk_barrier_failures;
3473 }
3474
3475 ret = insert_balance_item(fs_info->tree_root, bctl);
3476 if (ret && ret != -EEXIST)
3477 goto out;
3478
3479 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3480 BUG_ON(ret == -EEXIST);
3481 set_balance_control(bctl);
3482 } else {
3483 BUG_ON(ret != -EEXIST);
3484 spin_lock(&fs_info->balance_lock);
3485 update_balance_args(bctl);
3486 spin_unlock(&fs_info->balance_lock);
3487 }
3488
3489 atomic_inc(&fs_info->balance_running);
3490 mutex_unlock(&fs_info->balance_mutex);
3491
3492 ret = __btrfs_balance(fs_info);
3493
3494 mutex_lock(&fs_info->balance_mutex);
3495 atomic_dec(&fs_info->balance_running);
3496
3497 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3498 fs_info->num_tolerated_disk_barrier_failures =
3499 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3500 }
3501
3502 if (bargs) {
3503 memset(bargs, 0, sizeof(*bargs));
3504 update_ioctl_balance_args(fs_info, 0, bargs);
3505 }
3506
3507 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3508 balance_need_close(fs_info)) {
3509 __cancel_balance(fs_info);
3510 }
3511
3512 wake_up(&fs_info->balance_wait_q);
3513
3514 return ret;
3515 out:
3516 if (bctl->flags & BTRFS_BALANCE_RESUME)
3517 __cancel_balance(fs_info);
3518 else {
3519 kfree(bctl);
3520 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3521 }
3522 return ret;
3523 }
3524
3525 static int balance_kthread(void *data)
3526 {
3527 struct btrfs_fs_info *fs_info = data;
3528 int ret = 0;
3529
3530 mutex_lock(&fs_info->volume_mutex);
3531 mutex_lock(&fs_info->balance_mutex);
3532
3533 if (fs_info->balance_ctl) {
3534 btrfs_info(fs_info, "continuing balance");
3535 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3536 }
3537
3538 mutex_unlock(&fs_info->balance_mutex);
3539 mutex_unlock(&fs_info->volume_mutex);
3540
3541 return ret;
3542 }
3543
3544 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3545 {
3546 struct task_struct *tsk;
3547
3548 spin_lock(&fs_info->balance_lock);
3549 if (!fs_info->balance_ctl) {
3550 spin_unlock(&fs_info->balance_lock);
3551 return 0;
3552 }
3553 spin_unlock(&fs_info->balance_lock);
3554
3555 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3556 btrfs_info(fs_info, "force skipping balance");
3557 return 0;
3558 }
3559
3560 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3561 return PTR_ERR_OR_ZERO(tsk);
3562 }
3563
3564 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3565 {
3566 struct btrfs_balance_control *bctl;
3567 struct btrfs_balance_item *item;
3568 struct btrfs_disk_balance_args disk_bargs;
3569 struct btrfs_path *path;
3570 struct extent_buffer *leaf;
3571 struct btrfs_key key;
3572 int ret;
3573
3574 path = btrfs_alloc_path();
3575 if (!path)
3576 return -ENOMEM;
3577
3578 key.objectid = BTRFS_BALANCE_OBJECTID;
3579 key.type = BTRFS_BALANCE_ITEM_KEY;
3580 key.offset = 0;
3581
3582 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3583 if (ret < 0)
3584 goto out;
3585 if (ret > 0) { /* ret = -ENOENT; */
3586 ret = 0;
3587 goto out;
3588 }
3589
3590 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3591 if (!bctl) {
3592 ret = -ENOMEM;
3593 goto out;
3594 }
3595
3596 leaf = path->nodes[0];
3597 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3598
3599 bctl->fs_info = fs_info;
3600 bctl->flags = btrfs_balance_flags(leaf, item);
3601 bctl->flags |= BTRFS_BALANCE_RESUME;
3602
3603 btrfs_balance_data(leaf, item, &disk_bargs);
3604 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3605 btrfs_balance_meta(leaf, item, &disk_bargs);
3606 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3607 btrfs_balance_sys(leaf, item, &disk_bargs);
3608 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3609
3610 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3611
3612 mutex_lock(&fs_info->volume_mutex);
3613 mutex_lock(&fs_info->balance_mutex);
3614
3615 set_balance_control(bctl);
3616
3617 mutex_unlock(&fs_info->balance_mutex);
3618 mutex_unlock(&fs_info->volume_mutex);
3619 out:
3620 btrfs_free_path(path);
3621 return ret;
3622 }
3623
3624 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3625 {
3626 int ret = 0;
3627
3628 mutex_lock(&fs_info->balance_mutex);
3629 if (!fs_info->balance_ctl) {
3630 mutex_unlock(&fs_info->balance_mutex);
3631 return -ENOTCONN;
3632 }
3633
3634 if (atomic_read(&fs_info->balance_running)) {
3635 atomic_inc(&fs_info->balance_pause_req);
3636 mutex_unlock(&fs_info->balance_mutex);
3637
3638 wait_event(fs_info->balance_wait_q,
3639 atomic_read(&fs_info->balance_running) == 0);
3640
3641 mutex_lock(&fs_info->balance_mutex);
3642 /* we are good with balance_ctl ripped off from under us */
3643 BUG_ON(atomic_read(&fs_info->balance_running));
3644 atomic_dec(&fs_info->balance_pause_req);
3645 } else {
3646 ret = -ENOTCONN;
3647 }
3648
3649 mutex_unlock(&fs_info->balance_mutex);
3650 return ret;
3651 }
3652
3653 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3654 {
3655 if (fs_info->sb->s_flags & MS_RDONLY)
3656 return -EROFS;
3657
3658 mutex_lock(&fs_info->balance_mutex);
3659 if (!fs_info->balance_ctl) {
3660 mutex_unlock(&fs_info->balance_mutex);
3661 return -ENOTCONN;
3662 }
3663
3664 atomic_inc(&fs_info->balance_cancel_req);
3665 /*
3666 * if we are running just wait and return, balance item is
3667 * deleted in btrfs_balance in this case
3668 */
3669 if (atomic_read(&fs_info->balance_running)) {
3670 mutex_unlock(&fs_info->balance_mutex);
3671 wait_event(fs_info->balance_wait_q,
3672 atomic_read(&fs_info->balance_running) == 0);
3673 mutex_lock(&fs_info->balance_mutex);
3674 } else {
3675 /* __cancel_balance needs volume_mutex */
3676 mutex_unlock(&fs_info->balance_mutex);
3677 mutex_lock(&fs_info->volume_mutex);
3678 mutex_lock(&fs_info->balance_mutex);
3679
3680 if (fs_info->balance_ctl)
3681 __cancel_balance(fs_info);
3682
3683 mutex_unlock(&fs_info->volume_mutex);
3684 }
3685
3686 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
3687 atomic_dec(&fs_info->balance_cancel_req);
3688 mutex_unlock(&fs_info->balance_mutex);
3689 return 0;
3690 }
3691
3692 static int btrfs_uuid_scan_kthread(void *data)
3693 {
3694 struct btrfs_fs_info *fs_info = data;
3695 struct btrfs_root *root = fs_info->tree_root;
3696 struct btrfs_key key;
3697 struct btrfs_key max_key;
3698 struct btrfs_path *path = NULL;
3699 int ret = 0;
3700 struct extent_buffer *eb;
3701 int slot;
3702 struct btrfs_root_item root_item;
3703 u32 item_size;
3704 struct btrfs_trans_handle *trans = NULL;
3705
3706 path = btrfs_alloc_path();
3707 if (!path) {
3708 ret = -ENOMEM;
3709 goto out;
3710 }
3711
3712 key.objectid = 0;
3713 key.type = BTRFS_ROOT_ITEM_KEY;
3714 key.offset = 0;
3715
3716 max_key.objectid = (u64)-1;
3717 max_key.type = BTRFS_ROOT_ITEM_KEY;
3718 max_key.offset = (u64)-1;
3719
3720 while (1) {
3721 ret = btrfs_search_forward(root, &key, path, 0);
3722 if (ret) {
3723 if (ret > 0)
3724 ret = 0;
3725 break;
3726 }
3727
3728 if (key.type != BTRFS_ROOT_ITEM_KEY ||
3729 (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
3730 key.objectid != BTRFS_FS_TREE_OBJECTID) ||
3731 key.objectid > BTRFS_LAST_FREE_OBJECTID)
3732 goto skip;
3733
3734 eb = path->nodes[0];
3735 slot = path->slots[0];
3736 item_size = btrfs_item_size_nr(eb, slot);
3737 if (item_size < sizeof(root_item))
3738 goto skip;
3739
3740 read_extent_buffer(eb, &root_item,
3741 btrfs_item_ptr_offset(eb, slot),
3742 (int)sizeof(root_item));
3743 if (btrfs_root_refs(&root_item) == 0)
3744 goto skip;
3745
3746 if (!btrfs_is_empty_uuid(root_item.uuid) ||
3747 !btrfs_is_empty_uuid(root_item.received_uuid)) {
3748 if (trans)
3749 goto update_tree;
3750
3751 btrfs_release_path(path);
3752 /*
3753 * 1 - subvol uuid item
3754 * 1 - received_subvol uuid item
3755 */
3756 trans = btrfs_start_transaction(fs_info->uuid_root, 2);
3757 if (IS_ERR(trans)) {
3758 ret = PTR_ERR(trans);
3759 break;
3760 }
3761 continue;
3762 } else {
3763 goto skip;
3764 }
3765 update_tree:
3766 if (!btrfs_is_empty_uuid(root_item.uuid)) {
3767 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3768 root_item.uuid,
3769 BTRFS_UUID_KEY_SUBVOL,
3770 key.objectid);
3771 if (ret < 0) {
3772 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3773 ret);
3774 break;
3775 }
3776 }
3777
3778 if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
3779 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3780 root_item.received_uuid,
3781 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
3782 key.objectid);
3783 if (ret < 0) {
3784 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3785 ret);
3786 break;
3787 }
3788 }
3789
3790 skip:
3791 if (trans) {
3792 ret = btrfs_end_transaction(trans, fs_info->uuid_root);
3793 trans = NULL;
3794 if (ret)
3795 break;
3796 }
3797
3798 btrfs_release_path(path);
3799 if (key.offset < (u64)-1) {
3800 key.offset++;
3801 } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
3802 key.offset = 0;
3803 key.type = BTRFS_ROOT_ITEM_KEY;
3804 } else if (key.objectid < (u64)-1) {
3805 key.offset = 0;
3806 key.type = BTRFS_ROOT_ITEM_KEY;
3807 key.objectid++;
3808 } else {
3809 break;
3810 }
3811 cond_resched();
3812 }
3813
3814 out:
3815 btrfs_free_path(path);
3816 if (trans && !IS_ERR(trans))
3817 btrfs_end_transaction(trans, fs_info->uuid_root);
3818 if (ret)
3819 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
3820 else
3821 fs_info->update_uuid_tree_gen = 1;
3822 up(&fs_info->uuid_tree_rescan_sem);
3823 return 0;
3824 }
3825
3826 /*
3827 * Callback for btrfs_uuid_tree_iterate().
3828 * returns:
3829 * 0 check succeeded, the entry is not outdated.
3830 * < 0 if an error occured.
3831 * > 0 if the check failed, which means the caller shall remove the entry.
3832 */
3833 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
3834 u8 *uuid, u8 type, u64 subid)
3835 {
3836 struct btrfs_key key;
3837 int ret = 0;
3838 struct btrfs_root *subvol_root;
3839
3840 if (type != BTRFS_UUID_KEY_SUBVOL &&
3841 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
3842 goto out;
3843
3844 key.objectid = subid;
3845 key.type = BTRFS_ROOT_ITEM_KEY;
3846 key.offset = (u64)-1;
3847 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
3848 if (IS_ERR(subvol_root)) {
3849 ret = PTR_ERR(subvol_root);
3850 if (ret == -ENOENT)
3851 ret = 1;
3852 goto out;
3853 }
3854
3855 switch (type) {
3856 case BTRFS_UUID_KEY_SUBVOL:
3857 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
3858 ret = 1;
3859 break;
3860 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
3861 if (memcmp(uuid, subvol_root->root_item.received_uuid,
3862 BTRFS_UUID_SIZE))
3863 ret = 1;
3864 break;
3865 }
3866
3867 out:
3868 return ret;
3869 }
3870
3871 static int btrfs_uuid_rescan_kthread(void *data)
3872 {
3873 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
3874 int ret;
3875
3876 /*
3877 * 1st step is to iterate through the existing UUID tree and
3878 * to delete all entries that contain outdated data.
3879 * 2nd step is to add all missing entries to the UUID tree.
3880 */
3881 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
3882 if (ret < 0) {
3883 btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
3884 up(&fs_info->uuid_tree_rescan_sem);
3885 return ret;
3886 }
3887 return btrfs_uuid_scan_kthread(data);
3888 }
3889
3890 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
3891 {
3892 struct btrfs_trans_handle *trans;
3893 struct btrfs_root *tree_root = fs_info->tree_root;
3894 struct btrfs_root *uuid_root;
3895 struct task_struct *task;
3896 int ret;
3897
3898 /*
3899 * 1 - root node
3900 * 1 - root item
3901 */
3902 trans = btrfs_start_transaction(tree_root, 2);
3903 if (IS_ERR(trans))
3904 return PTR_ERR(trans);
3905
3906 uuid_root = btrfs_create_tree(trans, fs_info,
3907 BTRFS_UUID_TREE_OBJECTID);
3908 if (IS_ERR(uuid_root)) {
3909 btrfs_abort_transaction(trans, tree_root,
3910 PTR_ERR(uuid_root));
3911 return PTR_ERR(uuid_root);
3912 }
3913
3914 fs_info->uuid_root = uuid_root;
3915
3916 ret = btrfs_commit_transaction(trans, tree_root);
3917 if (ret)
3918 return ret;
3919
3920 down(&fs_info->uuid_tree_rescan_sem);
3921 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
3922 if (IS_ERR(task)) {
3923 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3924 btrfs_warn(fs_info, "failed to start uuid_scan task");
3925 up(&fs_info->uuid_tree_rescan_sem);
3926 return PTR_ERR(task);
3927 }
3928
3929 return 0;
3930 }
3931
3932 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
3933 {
3934 struct task_struct *task;
3935
3936 down(&fs_info->uuid_tree_rescan_sem);
3937 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
3938 if (IS_ERR(task)) {
3939 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3940 btrfs_warn(fs_info, "failed to start uuid_rescan task");
3941 up(&fs_info->uuid_tree_rescan_sem);
3942 return PTR_ERR(task);
3943 }
3944
3945 return 0;
3946 }
3947
3948 /*
3949 * shrinking a device means finding all of the device extents past
3950 * the new size, and then following the back refs to the chunks.
3951 * The chunk relocation code actually frees the device extent
3952 */
3953 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
3954 {
3955 struct btrfs_trans_handle *trans;
3956 struct btrfs_root *root = device->dev_root;
3957 struct btrfs_dev_extent *dev_extent = NULL;
3958 struct btrfs_path *path;
3959 u64 length;
3960 u64 chunk_tree;
3961 u64 chunk_objectid;
3962 u64 chunk_offset;
3963 int ret;
3964 int slot;
3965 int failed = 0;
3966 bool retried = false;
3967 struct extent_buffer *l;
3968 struct btrfs_key key;
3969 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3970 u64 old_total = btrfs_super_total_bytes(super_copy);
3971 u64 old_size = btrfs_device_get_total_bytes(device);
3972 u64 diff = old_size - new_size;
3973
3974 if (device->is_tgtdev_for_dev_replace)
3975 return -EINVAL;
3976
3977 path = btrfs_alloc_path();
3978 if (!path)
3979 return -ENOMEM;
3980
3981 path->reada = 2;
3982
3983 lock_chunks(root);
3984
3985 btrfs_device_set_total_bytes(device, new_size);
3986 if (device->writeable) {
3987 device->fs_devices->total_rw_bytes -= diff;
3988 spin_lock(&root->fs_info->free_chunk_lock);
3989 root->fs_info->free_chunk_space -= diff;
3990 spin_unlock(&root->fs_info->free_chunk_lock);
3991 }
3992 unlock_chunks(root);
3993
3994 again:
3995 key.objectid = device->devid;
3996 key.offset = (u64)-1;
3997 key.type = BTRFS_DEV_EXTENT_KEY;
3998
3999 do {
4000 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4001 if (ret < 0)
4002 goto done;
4003
4004 ret = btrfs_previous_item(root, path, 0, key.type);
4005 if (ret < 0)
4006 goto done;
4007 if (ret) {
4008 ret = 0;
4009 btrfs_release_path(path);
4010 break;
4011 }
4012
4013 l = path->nodes[0];
4014 slot = path->slots[0];
4015 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
4016
4017 if (key.objectid != device->devid) {
4018 btrfs_release_path(path);
4019 break;
4020 }
4021
4022 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
4023 length = btrfs_dev_extent_length(l, dev_extent);
4024
4025 if (key.offset + length <= new_size) {
4026 btrfs_release_path(path);
4027 break;
4028 }
4029
4030 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
4031 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
4032 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
4033 btrfs_release_path(path);
4034
4035 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
4036 chunk_offset);
4037 if (ret && ret != -ENOSPC)
4038 goto done;
4039 if (ret == -ENOSPC)
4040 failed++;
4041 } while (key.offset-- > 0);
4042
4043 if (failed && !retried) {
4044 failed = 0;
4045 retried = true;
4046 goto again;
4047 } else if (failed && retried) {
4048 ret = -ENOSPC;
4049 lock_chunks(root);
4050
4051 btrfs_device_set_total_bytes(device, old_size);
4052 if (device->writeable)
4053 device->fs_devices->total_rw_bytes += diff;
4054 spin_lock(&root->fs_info->free_chunk_lock);
4055 root->fs_info->free_chunk_space += diff;
4056 spin_unlock(&root->fs_info->free_chunk_lock);
4057 unlock_chunks(root);
4058 goto done;
4059 }
4060
4061 /* Shrinking succeeded, else we would be at "done". */
4062 trans = btrfs_start_transaction(root, 0);
4063 if (IS_ERR(trans)) {
4064 ret = PTR_ERR(trans);
4065 goto done;
4066 }
4067
4068 lock_chunks(root);
4069 btrfs_device_set_disk_total_bytes(device, new_size);
4070 if (list_empty(&device->resized_list))
4071 list_add_tail(&device->resized_list,
4072 &root->fs_info->fs_devices->resized_devices);
4073
4074 WARN_ON(diff > old_total);
4075 btrfs_set_super_total_bytes(super_copy, old_total - diff);
4076 unlock_chunks(root);
4077
4078 /* Now btrfs_update_device() will change the on-disk size. */
4079 ret = btrfs_update_device(trans, device);
4080 btrfs_end_transaction(trans, root);
4081 done:
4082 btrfs_free_path(path);
4083 return ret;
4084 }
4085
4086 static int btrfs_add_system_chunk(struct btrfs_root *root,
4087 struct btrfs_key *key,
4088 struct btrfs_chunk *chunk, int item_size)
4089 {
4090 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4091 struct btrfs_disk_key disk_key;
4092 u32 array_size;
4093 u8 *ptr;
4094
4095 lock_chunks(root);
4096 array_size = btrfs_super_sys_array_size(super_copy);
4097 if (array_size + item_size + sizeof(disk_key)
4098 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
4099 unlock_chunks(root);
4100 return -EFBIG;
4101 }
4102
4103 ptr = super_copy->sys_chunk_array + array_size;
4104 btrfs_cpu_key_to_disk(&disk_key, key);
4105 memcpy(ptr, &disk_key, sizeof(disk_key));
4106 ptr += sizeof(disk_key);
4107 memcpy(ptr, chunk, item_size);
4108 item_size += sizeof(disk_key);
4109 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
4110 unlock_chunks(root);
4111
4112 return 0;
4113 }
4114
4115 /*
4116 * sort the devices in descending order by max_avail, total_avail
4117 */
4118 static int btrfs_cmp_device_info(const void *a, const void *b)
4119 {
4120 const struct btrfs_device_info *di_a = a;
4121 const struct btrfs_device_info *di_b = b;
4122
4123 if (di_a->max_avail > di_b->max_avail)
4124 return -1;
4125 if (di_a->max_avail < di_b->max_avail)
4126 return 1;
4127 if (di_a->total_avail > di_b->total_avail)
4128 return -1;
4129 if (di_a->total_avail < di_b->total_avail)
4130 return 1;
4131 return 0;
4132 }
4133
4134 static struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
4135 [BTRFS_RAID_RAID10] = {
4136 .sub_stripes = 2,
4137 .dev_stripes = 1,
4138 .devs_max = 0, /* 0 == as many as possible */
4139 .devs_min = 4,
4140 .devs_increment = 2,
4141 .ncopies = 2,
4142 },
4143 [BTRFS_RAID_RAID1] = {
4144 .sub_stripes = 1,
4145 .dev_stripes = 1,
4146 .devs_max = 2,
4147 .devs_min = 2,
4148 .devs_increment = 2,
4149 .ncopies = 2,
4150 },
4151 [BTRFS_RAID_DUP] = {
4152 .sub_stripes = 1,
4153 .dev_stripes = 2,
4154 .devs_max = 1,
4155 .devs_min = 1,
4156 .devs_increment = 1,
4157 .ncopies = 2,
4158 },
4159 [BTRFS_RAID_RAID0] = {
4160 .sub_stripes = 1,
4161 .dev_stripes = 1,
4162 .devs_max = 0,
4163 .devs_min = 2,
4164 .devs_increment = 1,
4165 .ncopies = 1,
4166 },
4167 [BTRFS_RAID_SINGLE] = {
4168 .sub_stripes = 1,
4169 .dev_stripes = 1,
4170 .devs_max = 1,
4171 .devs_min = 1,
4172 .devs_increment = 1,
4173 .ncopies = 1,
4174 },
4175 [BTRFS_RAID_RAID5] = {
4176 .sub_stripes = 1,
4177 .dev_stripes = 1,
4178 .devs_max = 0,
4179 .devs_min = 2,
4180 .devs_increment = 1,
4181 .ncopies = 2,
4182 },
4183 [BTRFS_RAID_RAID6] = {
4184 .sub_stripes = 1,
4185 .dev_stripes = 1,
4186 .devs_max = 0,
4187 .devs_min = 3,
4188 .devs_increment = 1,
4189 .ncopies = 3,
4190 },
4191 };
4192
4193 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
4194 {
4195 /* TODO allow them to set a preferred stripe size */
4196 return 64 * 1024;
4197 }
4198
4199 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
4200 {
4201 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
4202 return;
4203
4204 btrfs_set_fs_incompat(info, RAID56);
4205 }
4206
4207 #define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \
4208 - sizeof(struct btrfs_item) \
4209 - sizeof(struct btrfs_chunk)) \
4210 / sizeof(struct btrfs_stripe) + 1)
4211
4212 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
4213 - 2 * sizeof(struct btrfs_disk_key) \
4214 - 2 * sizeof(struct btrfs_chunk)) \
4215 / sizeof(struct btrfs_stripe) + 1)
4216
4217 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4218 struct btrfs_root *extent_root, u64 start,
4219 u64 type)
4220 {
4221 struct btrfs_fs_info *info = extent_root->fs_info;
4222 struct btrfs_fs_devices *fs_devices = info->fs_devices;
4223 struct list_head *cur;
4224 struct map_lookup *map = NULL;
4225 struct extent_map_tree *em_tree;
4226 struct extent_map *em;
4227 struct btrfs_device_info *devices_info = NULL;
4228 u64 total_avail;
4229 int num_stripes; /* total number of stripes to allocate */
4230 int data_stripes; /* number of stripes that count for
4231 block group size */
4232 int sub_stripes; /* sub_stripes info for map */
4233 int dev_stripes; /* stripes per dev */
4234 int devs_max; /* max devs to use */
4235 int devs_min; /* min devs needed */
4236 int devs_increment; /* ndevs has to be a multiple of this */
4237 int ncopies; /* how many copies to data has */
4238 int ret;
4239 u64 max_stripe_size;
4240 u64 max_chunk_size;
4241 u64 stripe_size;
4242 u64 num_bytes;
4243 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
4244 int ndevs;
4245 int i;
4246 int j;
4247 int index;
4248
4249 BUG_ON(!alloc_profile_is_valid(type, 0));
4250
4251 if (list_empty(&fs_devices->alloc_list))
4252 return -ENOSPC;
4253
4254 index = __get_raid_index(type);
4255
4256 sub_stripes = btrfs_raid_array[index].sub_stripes;
4257 dev_stripes = btrfs_raid_array[index].dev_stripes;
4258 devs_max = btrfs_raid_array[index].devs_max;
4259 devs_min = btrfs_raid_array[index].devs_min;
4260 devs_increment = btrfs_raid_array[index].devs_increment;
4261 ncopies = btrfs_raid_array[index].ncopies;
4262
4263 if (type & BTRFS_BLOCK_GROUP_DATA) {
4264 max_stripe_size = 1024 * 1024 * 1024;
4265 max_chunk_size = 10 * max_stripe_size;
4266 if (!devs_max)
4267 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4268 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
4269 /* for larger filesystems, use larger metadata chunks */
4270 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
4271 max_stripe_size = 1024 * 1024 * 1024;
4272 else
4273 max_stripe_size = 256 * 1024 * 1024;
4274 max_chunk_size = max_stripe_size;
4275 if (!devs_max)
4276 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4277 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
4278 max_stripe_size = 32 * 1024 * 1024;
4279 max_chunk_size = 2 * max_stripe_size;
4280 if (!devs_max)
4281 devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
4282 } else {
4283 btrfs_err(info, "invalid chunk type 0x%llx requested",
4284 type);
4285 BUG_ON(1);
4286 }
4287
4288 /* we don't want a chunk larger than 10% of writeable space */
4289 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
4290 max_chunk_size);
4291
4292 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices,
4293 GFP_NOFS);
4294 if (!devices_info)
4295 return -ENOMEM;
4296
4297 cur = fs_devices->alloc_list.next;
4298
4299 /*
4300 * in the first pass through the devices list, we gather information
4301 * about the available holes on each device.
4302 */
4303 ndevs = 0;
4304 while (cur != &fs_devices->alloc_list) {
4305 struct btrfs_device *device;
4306 u64 max_avail;
4307 u64 dev_offset;
4308
4309 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
4310
4311 cur = cur->next;
4312
4313 if (!device->writeable) {
4314 WARN(1, KERN_ERR
4315 "BTRFS: read-only device in alloc_list\n");
4316 continue;
4317 }
4318
4319 if (!device->in_fs_metadata ||
4320 device->is_tgtdev_for_dev_replace)
4321 continue;
4322
4323 if (device->total_bytes > device->bytes_used)
4324 total_avail = device->total_bytes - device->bytes_used;
4325 else
4326 total_avail = 0;
4327
4328 /* If there is no space on this device, skip it. */
4329 if (total_avail == 0)
4330 continue;
4331
4332 ret = find_free_dev_extent(trans, device,
4333 max_stripe_size * dev_stripes,
4334 &dev_offset, &max_avail);
4335 if (ret && ret != -ENOSPC)
4336 goto error;
4337
4338 if (ret == 0)
4339 max_avail = max_stripe_size * dev_stripes;
4340
4341 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
4342 continue;
4343
4344 if (ndevs == fs_devices->rw_devices) {
4345 WARN(1, "%s: found more than %llu devices\n",
4346 __func__, fs_devices->rw_devices);
4347 break;
4348 }
4349 devices_info[ndevs].dev_offset = dev_offset;
4350 devices_info[ndevs].max_avail = max_avail;
4351 devices_info[ndevs].total_avail = total_avail;
4352 devices_info[ndevs].dev = device;
4353 ++ndevs;
4354 }
4355
4356 /*
4357 * now sort the devices by hole size / available space
4358 */
4359 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
4360 btrfs_cmp_device_info, NULL);
4361
4362 /* round down to number of usable stripes */
4363 ndevs -= ndevs % devs_increment;
4364
4365 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
4366 ret = -ENOSPC;
4367 goto error;
4368 }
4369
4370 if (devs_max && ndevs > devs_max)
4371 ndevs = devs_max;
4372 /*
4373 * the primary goal is to maximize the number of stripes, so use as many
4374 * devices as possible, even if the stripes are not maximum sized.
4375 */
4376 stripe_size = devices_info[ndevs-1].max_avail;
4377 num_stripes = ndevs * dev_stripes;
4378
4379 /*
4380 * this will have to be fixed for RAID1 and RAID10 over
4381 * more drives
4382 */
4383 data_stripes = num_stripes / ncopies;
4384
4385 if (type & BTRFS_BLOCK_GROUP_RAID5) {
4386 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
4387 btrfs_super_stripesize(info->super_copy));
4388 data_stripes = num_stripes - 1;
4389 }
4390 if (type & BTRFS_BLOCK_GROUP_RAID6) {
4391 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
4392 btrfs_super_stripesize(info->super_copy));
4393 data_stripes = num_stripes - 2;
4394 }
4395
4396 /*
4397 * Use the number of data stripes to figure out how big this chunk
4398 * is really going to be in terms of logical address space,
4399 * and compare that answer with the max chunk size
4400 */
4401 if (stripe_size * data_stripes > max_chunk_size) {
4402 u64 mask = (1ULL << 24) - 1;
4403 stripe_size = max_chunk_size;
4404 do_div(stripe_size, data_stripes);
4405
4406 /* bump the answer up to a 16MB boundary */
4407 stripe_size = (stripe_size + mask) & ~mask;
4408
4409 /* but don't go higher than the limits we found
4410 * while searching for free extents
4411 */
4412 if (stripe_size > devices_info[ndevs-1].max_avail)
4413 stripe_size = devices_info[ndevs-1].max_avail;
4414 }
4415
4416 do_div(stripe_size, dev_stripes);
4417
4418 /* align to BTRFS_STRIPE_LEN */
4419 do_div(stripe_size, raid_stripe_len);
4420 stripe_size *= raid_stripe_len;
4421
4422 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4423 if (!map) {
4424 ret = -ENOMEM;
4425 goto error;
4426 }
4427 map->num_stripes = num_stripes;
4428
4429 for (i = 0; i < ndevs; ++i) {
4430 for (j = 0; j < dev_stripes; ++j) {
4431 int s = i * dev_stripes + j;
4432 map->stripes[s].dev = devices_info[i].dev;
4433 map->stripes[s].physical = devices_info[i].dev_offset +
4434 j * stripe_size;
4435 }
4436 }
4437 map->sector_size = extent_root->sectorsize;
4438 map->stripe_len = raid_stripe_len;
4439 map->io_align = raid_stripe_len;
4440 map->io_width = raid_stripe_len;
4441 map->type = type;
4442 map->sub_stripes = sub_stripes;
4443
4444 num_bytes = stripe_size * data_stripes;
4445
4446 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
4447
4448 em = alloc_extent_map();
4449 if (!em) {
4450 kfree(map);
4451 ret = -ENOMEM;
4452 goto error;
4453 }
4454 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
4455 em->bdev = (struct block_device *)map;
4456 em->start = start;
4457 em->len = num_bytes;
4458 em->block_start = 0;
4459 em->block_len = em->len;
4460 em->orig_block_len = stripe_size;
4461
4462 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4463 write_lock(&em_tree->lock);
4464 ret = add_extent_mapping(em_tree, em, 0);
4465 if (!ret) {
4466 list_add_tail(&em->list, &trans->transaction->pending_chunks);
4467 atomic_inc(&em->refs);
4468 }
4469 write_unlock(&em_tree->lock);
4470 if (ret) {
4471 free_extent_map(em);
4472 goto error;
4473 }
4474
4475 ret = btrfs_make_block_group(trans, extent_root, 0, type,
4476 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4477 start, num_bytes);
4478 if (ret)
4479 goto error_del_extent;
4480
4481 for (i = 0; i < map->num_stripes; i++) {
4482 num_bytes = map->stripes[i].dev->bytes_used + stripe_size;
4483 btrfs_device_set_bytes_used(map->stripes[i].dev, num_bytes);
4484 }
4485
4486 spin_lock(&extent_root->fs_info->free_chunk_lock);
4487 extent_root->fs_info->free_chunk_space -= (stripe_size *
4488 map->num_stripes);
4489 spin_unlock(&extent_root->fs_info->free_chunk_lock);
4490
4491 free_extent_map(em);
4492 check_raid56_incompat_flag(extent_root->fs_info, type);
4493
4494 kfree(devices_info);
4495 return 0;
4496
4497 error_del_extent:
4498 write_lock(&em_tree->lock);
4499 remove_extent_mapping(em_tree, em);
4500 write_unlock(&em_tree->lock);
4501
4502 /* One for our allocation */
4503 free_extent_map(em);
4504 /* One for the tree reference */
4505 free_extent_map(em);
4506 /* One for the pending_chunks list reference */
4507 free_extent_map(em);
4508 error:
4509 kfree(devices_info);
4510 return ret;
4511 }
4512
4513 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
4514 struct btrfs_root *extent_root,
4515 u64 chunk_offset, u64 chunk_size)
4516 {
4517 struct btrfs_key key;
4518 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
4519 struct btrfs_device *device;
4520 struct btrfs_chunk *chunk;
4521 struct btrfs_stripe *stripe;
4522 struct extent_map_tree *em_tree;
4523 struct extent_map *em;
4524 struct map_lookup *map;
4525 size_t item_size;
4526 u64 dev_offset;
4527 u64 stripe_size;
4528 int i = 0;
4529 int ret;
4530
4531 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4532 read_lock(&em_tree->lock);
4533 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
4534 read_unlock(&em_tree->lock);
4535
4536 if (!em) {
4537 btrfs_crit(extent_root->fs_info, "unable to find logical "
4538 "%Lu len %Lu", chunk_offset, chunk_size);
4539 return -EINVAL;
4540 }
4541
4542 if (em->start != chunk_offset || em->len != chunk_size) {
4543 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted"
4544 " %Lu-%Lu, found %Lu-%Lu", chunk_offset,
4545 chunk_size, em->start, em->len);
4546 free_extent_map(em);
4547 return -EINVAL;
4548 }
4549
4550 map = (struct map_lookup *)em->bdev;
4551 item_size = btrfs_chunk_item_size(map->num_stripes);
4552 stripe_size = em->orig_block_len;
4553
4554 chunk = kzalloc(item_size, GFP_NOFS);
4555 if (!chunk) {
4556 ret = -ENOMEM;
4557 goto out;
4558 }
4559
4560 for (i = 0; i < map->num_stripes; i++) {
4561 device = map->stripes[i].dev;
4562 dev_offset = map->stripes[i].physical;
4563
4564 ret = btrfs_update_device(trans, device);
4565 if (ret)
4566 goto out;
4567 ret = btrfs_alloc_dev_extent(trans, device,
4568 chunk_root->root_key.objectid,
4569 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4570 chunk_offset, dev_offset,
4571 stripe_size);
4572 if (ret)
4573 goto out;
4574 }
4575
4576 stripe = &chunk->stripe;
4577 for (i = 0; i < map->num_stripes; i++) {
4578 device = map->stripes[i].dev;
4579 dev_offset = map->stripes[i].physical;
4580
4581 btrfs_set_stack_stripe_devid(stripe, device->devid);
4582 btrfs_set_stack_stripe_offset(stripe, dev_offset);
4583 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
4584 stripe++;
4585 }
4586
4587 btrfs_set_stack_chunk_length(chunk, chunk_size);
4588 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
4589 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
4590 btrfs_set_stack_chunk_type(chunk, map->type);
4591 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
4592 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
4593 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
4594 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
4595 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
4596
4597 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4598 key.type = BTRFS_CHUNK_ITEM_KEY;
4599 key.offset = chunk_offset;
4600
4601 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
4602 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
4603 /*
4604 * TODO: Cleanup of inserted chunk root in case of
4605 * failure.
4606 */
4607 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
4608 item_size);
4609 }
4610
4611 out:
4612 kfree(chunk);
4613 free_extent_map(em);
4614 return ret;
4615 }
4616
4617 /*
4618 * Chunk allocation falls into two parts. The first part does works
4619 * that make the new allocated chunk useable, but not do any operation
4620 * that modifies the chunk tree. The second part does the works that
4621 * require modifying the chunk tree. This division is important for the
4622 * bootstrap process of adding storage to a seed btrfs.
4623 */
4624 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4625 struct btrfs_root *extent_root, u64 type)
4626 {
4627 u64 chunk_offset;
4628
4629 chunk_offset = find_next_chunk(extent_root->fs_info);
4630 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type);
4631 }
4632
4633 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
4634 struct btrfs_root *root,
4635 struct btrfs_device *device)
4636 {
4637 u64 chunk_offset;
4638 u64 sys_chunk_offset;
4639 u64 alloc_profile;
4640 struct btrfs_fs_info *fs_info = root->fs_info;
4641 struct btrfs_root *extent_root = fs_info->extent_root;
4642 int ret;
4643
4644 chunk_offset = find_next_chunk(fs_info);
4645 alloc_profile = btrfs_get_alloc_profile(extent_root, 0);
4646 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset,
4647 alloc_profile);
4648 if (ret)
4649 return ret;
4650
4651 sys_chunk_offset = find_next_chunk(root->fs_info);
4652 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
4653 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset,
4654 alloc_profile);
4655 return ret;
4656 }
4657
4658 static inline int btrfs_chunk_max_errors(struct map_lookup *map)
4659 {
4660 int max_errors;
4661
4662 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
4663 BTRFS_BLOCK_GROUP_RAID10 |
4664 BTRFS_BLOCK_GROUP_RAID5 |
4665 BTRFS_BLOCK_GROUP_DUP)) {
4666 max_errors = 1;
4667 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
4668 max_errors = 2;
4669 } else {
4670 max_errors = 0;
4671 }
4672
4673 return max_errors;
4674 }
4675
4676 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
4677 {
4678 struct extent_map *em;
4679 struct map_lookup *map;
4680 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4681 int readonly = 0;
4682 int miss_ndevs = 0;
4683 int i;
4684
4685 read_lock(&map_tree->map_tree.lock);
4686 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
4687 read_unlock(&map_tree->map_tree.lock);
4688 if (!em)
4689 return 1;
4690
4691 map = (struct map_lookup *)em->bdev;
4692 for (i = 0; i < map->num_stripes; i++) {
4693 if (map->stripes[i].dev->missing) {
4694 miss_ndevs++;
4695 continue;
4696 }
4697
4698 if (!map->stripes[i].dev->writeable) {
4699 readonly = 1;
4700 goto end;
4701 }
4702 }
4703
4704 /*
4705 * If the number of missing devices is larger than max errors,
4706 * we can not write the data into that chunk successfully, so
4707 * set it readonly.
4708 */
4709 if (miss_ndevs > btrfs_chunk_max_errors(map))
4710 readonly = 1;
4711 end:
4712 free_extent_map(em);
4713 return readonly;
4714 }
4715
4716 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
4717 {
4718 extent_map_tree_init(&tree->map_tree);
4719 }
4720
4721 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
4722 {
4723 struct extent_map *em;
4724
4725 while (1) {
4726 write_lock(&tree->map_tree.lock);
4727 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
4728 if (em)
4729 remove_extent_mapping(&tree->map_tree, em);
4730 write_unlock(&tree->map_tree.lock);
4731 if (!em)
4732 break;
4733 /* once for us */
4734 free_extent_map(em);
4735 /* once for the tree */
4736 free_extent_map(em);
4737 }
4738 }
4739
4740 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
4741 {
4742 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4743 struct extent_map *em;
4744 struct map_lookup *map;
4745 struct extent_map_tree *em_tree = &map_tree->map_tree;
4746 int ret;
4747
4748 read_lock(&em_tree->lock);
4749 em = lookup_extent_mapping(em_tree, logical, len);
4750 read_unlock(&em_tree->lock);
4751
4752 /*
4753 * We could return errors for these cases, but that could get ugly and
4754 * we'd probably do the same thing which is just not do anything else
4755 * and exit, so return 1 so the callers don't try to use other copies.
4756 */
4757 if (!em) {
4758 btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
4759 logical+len);
4760 return 1;
4761 }
4762
4763 if (em->start > logical || em->start + em->len < logical) {
4764 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got "
4765 "%Lu-%Lu", logical, logical+len, em->start,
4766 em->start + em->len);
4767 free_extent_map(em);
4768 return 1;
4769 }
4770
4771 map = (struct map_lookup *)em->bdev;
4772 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
4773 ret = map->num_stripes;
4774 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
4775 ret = map->sub_stripes;
4776 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
4777 ret = 2;
4778 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
4779 ret = 3;
4780 else
4781 ret = 1;
4782 free_extent_map(em);
4783
4784 btrfs_dev_replace_lock(&fs_info->dev_replace);
4785 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
4786 ret++;
4787 btrfs_dev_replace_unlock(&fs_info->dev_replace);
4788
4789 return ret;
4790 }
4791
4792 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
4793 struct btrfs_mapping_tree *map_tree,
4794 u64 logical)
4795 {
4796 struct extent_map *em;
4797 struct map_lookup *map;
4798 struct extent_map_tree *em_tree = &map_tree->map_tree;
4799 unsigned long len = root->sectorsize;
4800
4801 read_lock(&em_tree->lock);
4802 em = lookup_extent_mapping(em_tree, logical, len);
4803 read_unlock(&em_tree->lock);
4804 BUG_ON(!em);
4805
4806 BUG_ON(em->start > logical || em->start + em->len < logical);
4807 map = (struct map_lookup *)em->bdev;
4808 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
4809 len = map->stripe_len * nr_data_stripes(map);
4810 free_extent_map(em);
4811 return len;
4812 }
4813
4814 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
4815 u64 logical, u64 len, int mirror_num)
4816 {
4817 struct extent_map *em;
4818 struct map_lookup *map;
4819 struct extent_map_tree *em_tree = &map_tree->map_tree;
4820 int ret = 0;
4821
4822 read_lock(&em_tree->lock);
4823 em = lookup_extent_mapping(em_tree, logical, len);
4824 read_unlock(&em_tree->lock);
4825 BUG_ON(!em);
4826
4827 BUG_ON(em->start > logical || em->start + em->len < logical);
4828 map = (struct map_lookup *)em->bdev;
4829 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
4830 ret = 1;
4831 free_extent_map(em);
4832 return ret;
4833 }
4834
4835 static int find_live_mirror(struct btrfs_fs_info *fs_info,
4836 struct map_lookup *map, int first, int num,
4837 int optimal, int dev_replace_is_ongoing)
4838 {
4839 int i;
4840 int tolerance;
4841 struct btrfs_device *srcdev;
4842
4843 if (dev_replace_is_ongoing &&
4844 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
4845 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
4846 srcdev = fs_info->dev_replace.srcdev;
4847 else
4848 srcdev = NULL;
4849
4850 /*
4851 * try to avoid the drive that is the source drive for a
4852 * dev-replace procedure, only choose it if no other non-missing
4853 * mirror is available
4854 */
4855 for (tolerance = 0; tolerance < 2; tolerance++) {
4856 if (map->stripes[optimal].dev->bdev &&
4857 (tolerance || map->stripes[optimal].dev != srcdev))
4858 return optimal;
4859 for (i = first; i < first + num; i++) {
4860 if (map->stripes[i].dev->bdev &&
4861 (tolerance || map->stripes[i].dev != srcdev))
4862 return i;
4863 }
4864 }
4865
4866 /* we couldn't find one that doesn't fail. Just return something
4867 * and the io error handling code will clean up eventually
4868 */
4869 return optimal;
4870 }
4871
4872 static inline int parity_smaller(u64 a, u64 b)
4873 {
4874 return a > b;
4875 }
4876
4877 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
4878 static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes)
4879 {
4880 struct btrfs_bio_stripe s;
4881 int i;
4882 u64 l;
4883 int again = 1;
4884
4885 while (again) {
4886 again = 0;
4887 for (i = 0; i < num_stripes - 1; i++) {
4888 if (parity_smaller(bbio->raid_map[i],
4889 bbio->raid_map[i+1])) {
4890 s = bbio->stripes[i];
4891 l = bbio->raid_map[i];
4892 bbio->stripes[i] = bbio->stripes[i+1];
4893 bbio->raid_map[i] = bbio->raid_map[i+1];
4894 bbio->stripes[i+1] = s;
4895 bbio->raid_map[i+1] = l;
4896
4897 again = 1;
4898 }
4899 }
4900 }
4901 }
4902
4903 static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
4904 {
4905 struct btrfs_bio *bbio = kzalloc(
4906 /* the size of the btrfs_bio */
4907 sizeof(struct btrfs_bio) +
4908 /* plus the variable array for the stripes */
4909 sizeof(struct btrfs_bio_stripe) * (total_stripes) +
4910 /* plus the variable array for the tgt dev */
4911 sizeof(int) * (real_stripes) +
4912 /*
4913 * plus the raid_map, which includes both the tgt dev
4914 * and the stripes
4915 */
4916 sizeof(u64) * (total_stripes),
4917 GFP_NOFS);
4918 if (!bbio)
4919 return NULL;
4920
4921 atomic_set(&bbio->error, 0);
4922 atomic_set(&bbio->refs, 1);
4923
4924 return bbio;
4925 }
4926
4927 void btrfs_get_bbio(struct btrfs_bio *bbio)
4928 {
4929 WARN_ON(!atomic_read(&bbio->refs));
4930 atomic_inc(&bbio->refs);
4931 }
4932
4933 void btrfs_put_bbio(struct btrfs_bio *bbio)
4934 {
4935 if (!bbio)
4936 return;
4937 if (atomic_dec_and_test(&bbio->refs))
4938 kfree(bbio);
4939 }
4940
4941 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
4942 u64 logical, u64 *length,
4943 struct btrfs_bio **bbio_ret,
4944 int mirror_num, int need_raid_map)
4945 {
4946 struct extent_map *em;
4947 struct map_lookup *map;
4948 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4949 struct extent_map_tree *em_tree = &map_tree->map_tree;
4950 u64 offset;
4951 u64 stripe_offset;
4952 u64 stripe_end_offset;
4953 u64 stripe_nr;
4954 u64 stripe_nr_orig;
4955 u64 stripe_nr_end;
4956 u64 stripe_len;
4957 int stripe_index;
4958 int i;
4959 int ret = 0;
4960 int num_stripes;
4961 int max_errors = 0;
4962 int tgtdev_indexes = 0;
4963 struct btrfs_bio *bbio = NULL;
4964 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
4965 int dev_replace_is_ongoing = 0;
4966 int num_alloc_stripes;
4967 int patch_the_first_stripe_for_dev_replace = 0;
4968 u64 physical_to_patch_in_first_stripe = 0;
4969 u64 raid56_full_stripe_start = (u64)-1;
4970
4971 read_lock(&em_tree->lock);
4972 em = lookup_extent_mapping(em_tree, logical, *length);
4973 read_unlock(&em_tree->lock);
4974
4975 if (!em) {
4976 btrfs_crit(fs_info, "unable to find logical %llu len %llu",
4977 logical, *length);
4978 return -EINVAL;
4979 }
4980
4981 if (em->start > logical || em->start + em->len < logical) {
4982 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, "
4983 "found %Lu-%Lu", logical, em->start,
4984 em->start + em->len);
4985 free_extent_map(em);
4986 return -EINVAL;
4987 }
4988
4989 map = (struct map_lookup *)em->bdev;
4990 offset = logical - em->start;
4991
4992 stripe_len = map->stripe_len;
4993 stripe_nr = offset;
4994 /*
4995 * stripe_nr counts the total number of stripes we have to stride
4996 * to get to this block
4997 */
4998 do_div(stripe_nr, stripe_len);
4999
5000 stripe_offset = stripe_nr * stripe_len;
5001 BUG_ON(offset < stripe_offset);
5002
5003 /* stripe_offset is the offset of this block in its stripe*/
5004 stripe_offset = offset - stripe_offset;
5005
5006 /* if we're here for raid56, we need to know the stripe aligned start */
5007 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5008 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
5009 raid56_full_stripe_start = offset;
5010
5011 /* allow a write of a full stripe, but make sure we don't
5012 * allow straddling of stripes
5013 */
5014 do_div(raid56_full_stripe_start, full_stripe_len);
5015 raid56_full_stripe_start *= full_stripe_len;
5016 }
5017
5018 if (rw & REQ_DISCARD) {
5019 /* we don't discard raid56 yet */
5020 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5021 ret = -EOPNOTSUPP;
5022 goto out;
5023 }
5024 *length = min_t(u64, em->len - offset, *length);
5025 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
5026 u64 max_len;
5027 /* For writes to RAID[56], allow a full stripeset across all disks.
5028 For other RAID types and for RAID[56] reads, just allow a single
5029 stripe (on a single disk). */
5030 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
5031 (rw & REQ_WRITE)) {
5032 max_len = stripe_len * nr_data_stripes(map) -
5033 (offset - raid56_full_stripe_start);
5034 } else {
5035 /* we limit the length of each bio to what fits in a stripe */
5036 max_len = stripe_len - stripe_offset;
5037 }
5038 *length = min_t(u64, em->len - offset, max_len);
5039 } else {
5040 *length = em->len - offset;
5041 }
5042
5043 /* This is for when we're called from btrfs_merge_bio_hook() and all
5044 it cares about is the length */
5045 if (!bbio_ret)
5046 goto out;
5047
5048 btrfs_dev_replace_lock(dev_replace);
5049 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
5050 if (!dev_replace_is_ongoing)
5051 btrfs_dev_replace_unlock(dev_replace);
5052
5053 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
5054 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
5055 dev_replace->tgtdev != NULL) {
5056 /*
5057 * in dev-replace case, for repair case (that's the only
5058 * case where the mirror is selected explicitly when
5059 * calling btrfs_map_block), blocks left of the left cursor
5060 * can also be read from the target drive.
5061 * For REQ_GET_READ_MIRRORS, the target drive is added as
5062 * the last one to the array of stripes. For READ, it also
5063 * needs to be supported using the same mirror number.
5064 * If the requested block is not left of the left cursor,
5065 * EIO is returned. This can happen because btrfs_num_copies()
5066 * returns one more in the dev-replace case.
5067 */
5068 u64 tmp_length = *length;
5069 struct btrfs_bio *tmp_bbio = NULL;
5070 int tmp_num_stripes;
5071 u64 srcdev_devid = dev_replace->srcdev->devid;
5072 int index_srcdev = 0;
5073 int found = 0;
5074 u64 physical_of_found = 0;
5075
5076 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
5077 logical, &tmp_length, &tmp_bbio, 0, 0);
5078 if (ret) {
5079 WARN_ON(tmp_bbio != NULL);
5080 goto out;
5081 }
5082
5083 tmp_num_stripes = tmp_bbio->num_stripes;
5084 if (mirror_num > tmp_num_stripes) {
5085 /*
5086 * REQ_GET_READ_MIRRORS does not contain this
5087 * mirror, that means that the requested area
5088 * is not left of the left cursor
5089 */
5090 ret = -EIO;
5091 btrfs_put_bbio(tmp_bbio);
5092 goto out;
5093 }
5094
5095 /*
5096 * process the rest of the function using the mirror_num
5097 * of the source drive. Therefore look it up first.
5098 * At the end, patch the device pointer to the one of the
5099 * target drive.
5100 */
5101 for (i = 0; i < tmp_num_stripes; i++) {
5102 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) {
5103 /*
5104 * In case of DUP, in order to keep it
5105 * simple, only add the mirror with the
5106 * lowest physical address
5107 */
5108 if (found &&
5109 physical_of_found <=
5110 tmp_bbio->stripes[i].physical)
5111 continue;
5112 index_srcdev = i;
5113 found = 1;
5114 physical_of_found =
5115 tmp_bbio->stripes[i].physical;
5116 }
5117 }
5118
5119 if (found) {
5120 mirror_num = index_srcdev + 1;
5121 patch_the_first_stripe_for_dev_replace = 1;
5122 physical_to_patch_in_first_stripe = physical_of_found;
5123 } else {
5124 WARN_ON(1);
5125 ret = -EIO;
5126 btrfs_put_bbio(tmp_bbio);
5127 goto out;
5128 }
5129
5130 btrfs_put_bbio(tmp_bbio);
5131 } else if (mirror_num > map->num_stripes) {
5132 mirror_num = 0;
5133 }
5134
5135 num_stripes = 1;
5136 stripe_index = 0;
5137 stripe_nr_orig = stripe_nr;
5138 stripe_nr_end = ALIGN(offset + *length, map->stripe_len);
5139 do_div(stripe_nr_end, map->stripe_len);
5140 stripe_end_offset = stripe_nr_end * map->stripe_len -
5141 (offset + *length);
5142
5143 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5144 if (rw & REQ_DISCARD)
5145 num_stripes = min_t(u64, map->num_stripes,
5146 stripe_nr_end - stripe_nr_orig);
5147 stripe_index = do_div(stripe_nr, map->num_stripes);
5148 if (!(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)))
5149 mirror_num = 1;
5150 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
5151 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
5152 num_stripes = map->num_stripes;
5153 else if (mirror_num)
5154 stripe_index = mirror_num - 1;
5155 else {
5156 stripe_index = find_live_mirror(fs_info, map, 0,
5157 map->num_stripes,
5158 current->pid % map->num_stripes,
5159 dev_replace_is_ongoing);
5160 mirror_num = stripe_index + 1;
5161 }
5162
5163 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
5164 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
5165 num_stripes = map->num_stripes;
5166 } else if (mirror_num) {
5167 stripe_index = mirror_num - 1;
5168 } else {
5169 mirror_num = 1;
5170 }
5171
5172 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5173 int factor = map->num_stripes / map->sub_stripes;
5174
5175 stripe_index = do_div(stripe_nr, factor);
5176 stripe_index *= map->sub_stripes;
5177
5178 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5179 num_stripes = map->sub_stripes;
5180 else if (rw & REQ_DISCARD)
5181 num_stripes = min_t(u64, map->sub_stripes *
5182 (stripe_nr_end - stripe_nr_orig),
5183 map->num_stripes);
5184 else if (mirror_num)
5185 stripe_index += mirror_num - 1;
5186 else {
5187 int old_stripe_index = stripe_index;
5188 stripe_index = find_live_mirror(fs_info, map,
5189 stripe_index,
5190 map->sub_stripes, stripe_index +
5191 current->pid % map->sub_stripes,
5192 dev_replace_is_ongoing);
5193 mirror_num = stripe_index - old_stripe_index + 1;
5194 }
5195
5196 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5197 if (need_raid_map &&
5198 ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5199 mirror_num > 1)) {
5200 /* push stripe_nr back to the start of the full stripe */
5201 stripe_nr = raid56_full_stripe_start;
5202 do_div(stripe_nr, stripe_len * nr_data_stripes(map));
5203
5204 /* RAID[56] write or recovery. Return all stripes */
5205 num_stripes = map->num_stripes;
5206 max_errors = nr_parity_stripes(map);
5207
5208 *length = map->stripe_len;
5209 stripe_index = 0;
5210 stripe_offset = 0;
5211 } else {
5212 u64 tmp;
5213
5214 /*
5215 * Mirror #0 or #1 means the original data block.
5216 * Mirror #2 is RAID5 parity block.
5217 * Mirror #3 is RAID6 Q block.
5218 */
5219 stripe_index = do_div(stripe_nr, nr_data_stripes(map));
5220 if (mirror_num > 1)
5221 stripe_index = nr_data_stripes(map) +
5222 mirror_num - 2;
5223
5224 /* We distribute the parity blocks across stripes */
5225 tmp = stripe_nr + stripe_index;
5226 stripe_index = do_div(tmp, map->num_stripes);
5227 if (!(rw & (REQ_WRITE | REQ_DISCARD |
5228 REQ_GET_READ_MIRRORS)) && mirror_num <= 1)
5229 mirror_num = 1;
5230 }
5231 } else {
5232 /*
5233 * after this do_div call, stripe_nr is the number of stripes
5234 * on this device we have to walk to find the data, and
5235 * stripe_index is the number of our device in the stripe array
5236 */
5237 stripe_index = do_div(stripe_nr, map->num_stripes);
5238 mirror_num = stripe_index + 1;
5239 }
5240 BUG_ON(stripe_index >= map->num_stripes);
5241
5242 num_alloc_stripes = num_stripes;
5243 if (dev_replace_is_ongoing) {
5244 if (rw & (REQ_WRITE | REQ_DISCARD))
5245 num_alloc_stripes <<= 1;
5246 if (rw & REQ_GET_READ_MIRRORS)
5247 num_alloc_stripes++;
5248 tgtdev_indexes = num_stripes;
5249 }
5250
5251 bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes);
5252 if (!bbio) {
5253 ret = -ENOMEM;
5254 goto out;
5255 }
5256 if (dev_replace_is_ongoing)
5257 bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes);
5258
5259 /* build raid_map */
5260 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
5261 need_raid_map && ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5262 mirror_num > 1)) {
5263 u64 tmp;
5264 int i, rot;
5265
5266 bbio->raid_map = (u64 *)((void *)bbio->stripes +
5267 sizeof(struct btrfs_bio_stripe) *
5268 num_alloc_stripes +
5269 sizeof(int) * tgtdev_indexes);
5270
5271 /* Work out the disk rotation on this stripe-set */
5272 tmp = stripe_nr;
5273 rot = do_div(tmp, num_stripes);
5274
5275 /* Fill in the logical address of each stripe */
5276 tmp = stripe_nr * nr_data_stripes(map);
5277 for (i = 0; i < nr_data_stripes(map); i++)
5278 bbio->raid_map[(i+rot) % num_stripes] =
5279 em->start + (tmp + i) * map->stripe_len;
5280
5281 bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
5282 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5283 bbio->raid_map[(i+rot+1) % num_stripes] =
5284 RAID6_Q_STRIPE;
5285 }
5286
5287 if (rw & REQ_DISCARD) {
5288 int factor = 0;
5289 int sub_stripes = 0;
5290 u64 stripes_per_dev = 0;
5291 u32 remaining_stripes = 0;
5292 u32 last_stripe = 0;
5293
5294 if (map->type &
5295 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
5296 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5297 sub_stripes = 1;
5298 else
5299 sub_stripes = map->sub_stripes;
5300
5301 factor = map->num_stripes / sub_stripes;
5302 stripes_per_dev = div_u64_rem(stripe_nr_end -
5303 stripe_nr_orig,
5304 factor,
5305 &remaining_stripes);
5306 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
5307 last_stripe *= sub_stripes;
5308 }
5309
5310 for (i = 0; i < num_stripes; i++) {
5311 bbio->stripes[i].physical =
5312 map->stripes[stripe_index].physical +
5313 stripe_offset + stripe_nr * map->stripe_len;
5314 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
5315
5316 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
5317 BTRFS_BLOCK_GROUP_RAID10)) {
5318 bbio->stripes[i].length = stripes_per_dev *
5319 map->stripe_len;
5320
5321 if (i / sub_stripes < remaining_stripes)
5322 bbio->stripes[i].length +=
5323 map->stripe_len;
5324
5325 /*
5326 * Special for the first stripe and
5327 * the last stripe:
5328 *
5329 * |-------|...|-------|
5330 * |----------|
5331 * off end_off
5332 */
5333 if (i < sub_stripes)
5334 bbio->stripes[i].length -=
5335 stripe_offset;
5336
5337 if (stripe_index >= last_stripe &&
5338 stripe_index <= (last_stripe +
5339 sub_stripes - 1))
5340 bbio->stripes[i].length -=
5341 stripe_end_offset;
5342
5343 if (i == sub_stripes - 1)
5344 stripe_offset = 0;
5345 } else
5346 bbio->stripes[i].length = *length;
5347
5348 stripe_index++;
5349 if (stripe_index == map->num_stripes) {
5350 /* This could only happen for RAID0/10 */
5351 stripe_index = 0;
5352 stripe_nr++;
5353 }
5354 }
5355 } else {
5356 for (i = 0; i < num_stripes; i++) {
5357 bbio->stripes[i].physical =
5358 map->stripes[stripe_index].physical +
5359 stripe_offset +
5360 stripe_nr * map->stripe_len;
5361 bbio->stripes[i].dev =
5362 map->stripes[stripe_index].dev;
5363 stripe_index++;
5364 }
5365 }
5366
5367 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5368 max_errors = btrfs_chunk_max_errors(map);
5369
5370 if (bbio->raid_map)
5371 sort_parity_stripes(bbio, num_stripes);
5372
5373 tgtdev_indexes = 0;
5374 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
5375 dev_replace->tgtdev != NULL) {
5376 int index_where_to_add;
5377 u64 srcdev_devid = dev_replace->srcdev->devid;
5378
5379 /*
5380 * duplicate the write operations while the dev replace
5381 * procedure is running. Since the copying of the old disk
5382 * to the new disk takes place at run time while the
5383 * filesystem is mounted writable, the regular write
5384 * operations to the old disk have to be duplicated to go
5385 * to the new disk as well.
5386 * Note that device->missing is handled by the caller, and
5387 * that the write to the old disk is already set up in the
5388 * stripes array.
5389 */
5390 index_where_to_add = num_stripes;
5391 for (i = 0; i < num_stripes; i++) {
5392 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5393 /* write to new disk, too */
5394 struct btrfs_bio_stripe *new =
5395 bbio->stripes + index_where_to_add;
5396 struct btrfs_bio_stripe *old =
5397 bbio->stripes + i;
5398
5399 new->physical = old->physical;
5400 new->length = old->length;
5401 new->dev = dev_replace->tgtdev;
5402 bbio->tgtdev_map[i] = index_where_to_add;
5403 index_where_to_add++;
5404 max_errors++;
5405 tgtdev_indexes++;
5406 }
5407 }
5408 num_stripes = index_where_to_add;
5409 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
5410 dev_replace->tgtdev != NULL) {
5411 u64 srcdev_devid = dev_replace->srcdev->devid;
5412 int index_srcdev = 0;
5413 int found = 0;
5414 u64 physical_of_found = 0;
5415
5416 /*
5417 * During the dev-replace procedure, the target drive can
5418 * also be used to read data in case it is needed to repair
5419 * a corrupt block elsewhere. This is possible if the
5420 * requested area is left of the left cursor. In this area,
5421 * the target drive is a full copy of the source drive.
5422 */
5423 for (i = 0; i < num_stripes; i++) {
5424 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5425 /*
5426 * In case of DUP, in order to keep it
5427 * simple, only add the mirror with the
5428 * lowest physical address
5429 */
5430 if (found &&
5431 physical_of_found <=
5432 bbio->stripes[i].physical)
5433 continue;
5434 index_srcdev = i;
5435 found = 1;
5436 physical_of_found = bbio->stripes[i].physical;
5437 }
5438 }
5439 if (found) {
5440 u64 length = map->stripe_len;
5441
5442 if (physical_of_found + length <=
5443 dev_replace->cursor_left) {
5444 struct btrfs_bio_stripe *tgtdev_stripe =
5445 bbio->stripes + num_stripes;
5446
5447 tgtdev_stripe->physical = physical_of_found;
5448 tgtdev_stripe->length =
5449 bbio->stripes[index_srcdev].length;
5450 tgtdev_stripe->dev = dev_replace->tgtdev;
5451 bbio->tgtdev_map[index_srcdev] = num_stripes;
5452
5453 tgtdev_indexes++;
5454 num_stripes++;
5455 }
5456 }
5457 }
5458
5459 *bbio_ret = bbio;
5460 bbio->map_type = map->type;
5461 bbio->num_stripes = num_stripes;
5462 bbio->max_errors = max_errors;
5463 bbio->mirror_num = mirror_num;
5464 bbio->num_tgtdevs = tgtdev_indexes;
5465
5466 /*
5467 * this is the case that REQ_READ && dev_replace_is_ongoing &&
5468 * mirror_num == num_stripes + 1 && dev_replace target drive is
5469 * available as a mirror
5470 */
5471 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
5472 WARN_ON(num_stripes > 1);
5473 bbio->stripes[0].dev = dev_replace->tgtdev;
5474 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
5475 bbio->mirror_num = map->num_stripes + 1;
5476 }
5477 out:
5478 if (dev_replace_is_ongoing)
5479 btrfs_dev_replace_unlock(dev_replace);
5480 free_extent_map(em);
5481 return ret;
5482 }
5483
5484 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5485 u64 logical, u64 *length,
5486 struct btrfs_bio **bbio_ret, int mirror_num)
5487 {
5488 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5489 mirror_num, 0);
5490 }
5491
5492 /* For Scrub/replace */
5493 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
5494 u64 logical, u64 *length,
5495 struct btrfs_bio **bbio_ret, int mirror_num,
5496 int need_raid_map)
5497 {
5498 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5499 mirror_num, need_raid_map);
5500 }
5501
5502 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
5503 u64 chunk_start, u64 physical, u64 devid,
5504 u64 **logical, int *naddrs, int *stripe_len)
5505 {
5506 struct extent_map_tree *em_tree = &map_tree->map_tree;
5507 struct extent_map *em;
5508 struct map_lookup *map;
5509 u64 *buf;
5510 u64 bytenr;
5511 u64 length;
5512 u64 stripe_nr;
5513 u64 rmap_len;
5514 int i, j, nr = 0;
5515
5516 read_lock(&em_tree->lock);
5517 em = lookup_extent_mapping(em_tree, chunk_start, 1);
5518 read_unlock(&em_tree->lock);
5519
5520 if (!em) {
5521 printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
5522 chunk_start);
5523 return -EIO;
5524 }
5525
5526 if (em->start != chunk_start) {
5527 printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
5528 em->start, chunk_start);
5529 free_extent_map(em);
5530 return -EIO;
5531 }
5532 map = (struct map_lookup *)em->bdev;
5533
5534 length = em->len;
5535 rmap_len = map->stripe_len;
5536
5537 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5538 do_div(length, map->num_stripes / map->sub_stripes);
5539 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5540 do_div(length, map->num_stripes);
5541 else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5542 do_div(length, nr_data_stripes(map));
5543 rmap_len = map->stripe_len * nr_data_stripes(map);
5544 }
5545
5546 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
5547 BUG_ON(!buf); /* -ENOMEM */
5548
5549 for (i = 0; i < map->num_stripes; i++) {
5550 if (devid && map->stripes[i].dev->devid != devid)
5551 continue;
5552 if (map->stripes[i].physical > physical ||
5553 map->stripes[i].physical + length <= physical)
5554 continue;
5555
5556 stripe_nr = physical - map->stripes[i].physical;
5557 do_div(stripe_nr, map->stripe_len);
5558
5559 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5560 stripe_nr = stripe_nr * map->num_stripes + i;
5561 do_div(stripe_nr, map->sub_stripes);
5562 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5563 stripe_nr = stripe_nr * map->num_stripes + i;
5564 } /* else if RAID[56], multiply by nr_data_stripes().
5565 * Alternatively, just use rmap_len below instead of
5566 * map->stripe_len */
5567
5568 bytenr = chunk_start + stripe_nr * rmap_len;
5569 WARN_ON(nr >= map->num_stripes);
5570 for (j = 0; j < nr; j++) {
5571 if (buf[j] == bytenr)
5572 break;
5573 }
5574 if (j == nr) {
5575 WARN_ON(nr >= map->num_stripes);
5576 buf[nr++] = bytenr;
5577 }
5578 }
5579
5580 *logical = buf;
5581 *naddrs = nr;
5582 *stripe_len = rmap_len;
5583
5584 free_extent_map(em);
5585 return 0;
5586 }
5587
5588 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio, int err)
5589 {
5590 if (likely(bbio->flags & BTRFS_BIO_ORIG_BIO_SUBMITTED))
5591 bio_endio_nodec(bio, err);
5592 else
5593 bio_endio(bio, err);
5594 btrfs_put_bbio(bbio);
5595 }
5596
5597 static void btrfs_end_bio(struct bio *bio, int err)
5598 {
5599 struct btrfs_bio *bbio = bio->bi_private;
5600 struct btrfs_device *dev = bbio->stripes[0].dev;
5601 int is_orig_bio = 0;
5602
5603 if (err) {
5604 atomic_inc(&bbio->error);
5605 if (err == -EIO || err == -EREMOTEIO) {
5606 unsigned int stripe_index =
5607 btrfs_io_bio(bio)->stripe_index;
5608
5609 BUG_ON(stripe_index >= bbio->num_stripes);
5610 dev = bbio->stripes[stripe_index].dev;
5611 if (dev->bdev) {
5612 if (bio->bi_rw & WRITE)
5613 btrfs_dev_stat_inc(dev,
5614 BTRFS_DEV_STAT_WRITE_ERRS);
5615 else
5616 btrfs_dev_stat_inc(dev,
5617 BTRFS_DEV_STAT_READ_ERRS);
5618 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
5619 btrfs_dev_stat_inc(dev,
5620 BTRFS_DEV_STAT_FLUSH_ERRS);
5621 btrfs_dev_stat_print_on_error(dev);
5622 }
5623 }
5624 }
5625
5626 if (bio == bbio->orig_bio)
5627 is_orig_bio = 1;
5628
5629 btrfs_bio_counter_dec(bbio->fs_info);
5630
5631 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5632 if (!is_orig_bio) {
5633 bio_put(bio);
5634 bio = bbio->orig_bio;
5635 }
5636
5637 bio->bi_private = bbio->private;
5638 bio->bi_end_io = bbio->end_io;
5639 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5640 /* only send an error to the higher layers if it is
5641 * beyond the tolerance of the btrfs bio
5642 */
5643 if (atomic_read(&bbio->error) > bbio->max_errors) {
5644 err = -EIO;
5645 } else {
5646 /*
5647 * this bio is actually up to date, we didn't
5648 * go over the max number of errors
5649 */
5650 set_bit(BIO_UPTODATE, &bio->bi_flags);
5651 err = 0;
5652 }
5653
5654 btrfs_end_bbio(bbio, bio, err);
5655 } else if (!is_orig_bio) {
5656 bio_put(bio);
5657 }
5658 }
5659
5660 /*
5661 * see run_scheduled_bios for a description of why bios are collected for
5662 * async submit.
5663 *
5664 * This will add one bio to the pending list for a device and make sure
5665 * the work struct is scheduled.
5666 */
5667 static noinline void btrfs_schedule_bio(struct btrfs_root *root,
5668 struct btrfs_device *device,
5669 int rw, struct bio *bio)
5670 {
5671 int should_queue = 1;
5672 struct btrfs_pending_bios *pending_bios;
5673
5674 if (device->missing || !device->bdev) {
5675 bio_endio(bio, -EIO);
5676 return;
5677 }
5678
5679 /* don't bother with additional async steps for reads, right now */
5680 if (!(rw & REQ_WRITE)) {
5681 bio_get(bio);
5682 btrfsic_submit_bio(rw, bio);
5683 bio_put(bio);
5684 return;
5685 }
5686
5687 /*
5688 * nr_async_bios allows us to reliably return congestion to the
5689 * higher layers. Otherwise, the async bio makes it appear we have
5690 * made progress against dirty pages when we've really just put it
5691 * on a queue for later
5692 */
5693 atomic_inc(&root->fs_info->nr_async_bios);
5694 WARN_ON(bio->bi_next);
5695 bio->bi_next = NULL;
5696 bio->bi_rw |= rw;
5697
5698 spin_lock(&device->io_lock);
5699 if (bio->bi_rw & REQ_SYNC)
5700 pending_bios = &device->pending_sync_bios;
5701 else
5702 pending_bios = &device->pending_bios;
5703
5704 if (pending_bios->tail)
5705 pending_bios->tail->bi_next = bio;
5706
5707 pending_bios->tail = bio;
5708 if (!pending_bios->head)
5709 pending_bios->head = bio;
5710 if (device->running_pending)
5711 should_queue = 0;
5712
5713 spin_unlock(&device->io_lock);
5714
5715 if (should_queue)
5716 btrfs_queue_work(root->fs_info->submit_workers,
5717 &device->work);
5718 }
5719
5720 static int bio_size_ok(struct block_device *bdev, struct bio *bio,
5721 sector_t sector)
5722 {
5723 struct bio_vec *prev;
5724 struct request_queue *q = bdev_get_queue(bdev);
5725 unsigned int max_sectors = queue_max_sectors(q);
5726 struct bvec_merge_data bvm = {
5727 .bi_bdev = bdev,
5728 .bi_sector = sector,
5729 .bi_rw = bio->bi_rw,
5730 };
5731
5732 if (WARN_ON(bio->bi_vcnt == 0))
5733 return 1;
5734
5735 prev = &bio->bi_io_vec[bio->bi_vcnt - 1];
5736 if (bio_sectors(bio) > max_sectors)
5737 return 0;
5738
5739 if (!q->merge_bvec_fn)
5740 return 1;
5741
5742 bvm.bi_size = bio->bi_iter.bi_size - prev->bv_len;
5743 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len)
5744 return 0;
5745 return 1;
5746 }
5747
5748 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5749 struct bio *bio, u64 physical, int dev_nr,
5750 int rw, int async)
5751 {
5752 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
5753
5754 bio->bi_private = bbio;
5755 btrfs_io_bio(bio)->stripe_index = dev_nr;
5756 bio->bi_end_io = btrfs_end_bio;
5757 bio->bi_iter.bi_sector = physical >> 9;
5758 #ifdef DEBUG
5759 {
5760 struct rcu_string *name;
5761
5762 rcu_read_lock();
5763 name = rcu_dereference(dev->name);
5764 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
5765 "(%s id %llu), size=%u\n", rw,
5766 (u64)bio->bi_iter.bi_sector, (u_long)dev->bdev->bd_dev,
5767 name->str, dev->devid, bio->bi_iter.bi_size);
5768 rcu_read_unlock();
5769 }
5770 #endif
5771 bio->bi_bdev = dev->bdev;
5772
5773 btrfs_bio_counter_inc_noblocked(root->fs_info);
5774
5775 if (async)
5776 btrfs_schedule_bio(root, dev, rw, bio);
5777 else
5778 btrfsic_submit_bio(rw, bio);
5779 }
5780
5781 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5782 struct bio *first_bio, struct btrfs_device *dev,
5783 int dev_nr, int rw, int async)
5784 {
5785 struct bio_vec *bvec = first_bio->bi_io_vec;
5786 struct bio *bio;
5787 int nr_vecs = bio_get_nr_vecs(dev->bdev);
5788 u64 physical = bbio->stripes[dev_nr].physical;
5789
5790 again:
5791 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS);
5792 if (!bio)
5793 return -ENOMEM;
5794
5795 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) {
5796 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5797 bvec->bv_offset) < bvec->bv_len) {
5798 u64 len = bio->bi_iter.bi_size;
5799
5800 atomic_inc(&bbio->stripes_pending);
5801 submit_stripe_bio(root, bbio, bio, physical, dev_nr,
5802 rw, async);
5803 physical += len;
5804 goto again;
5805 }
5806 bvec++;
5807 }
5808
5809 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async);
5810 return 0;
5811 }
5812
5813 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
5814 {
5815 atomic_inc(&bbio->error);
5816 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5817 /* Shoud be the original bio. */
5818 WARN_ON(bio != bbio->orig_bio);
5819
5820 bio->bi_private = bbio->private;
5821 bio->bi_end_io = bbio->end_io;
5822 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5823 bio->bi_iter.bi_sector = logical >> 9;
5824
5825 btrfs_end_bbio(bbio, bio, -EIO);
5826 }
5827 }
5828
5829 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
5830 int mirror_num, int async_submit)
5831 {
5832 struct btrfs_device *dev;
5833 struct bio *first_bio = bio;
5834 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
5835 u64 length = 0;
5836 u64 map_length;
5837 int ret;
5838 int dev_nr = 0;
5839 int total_devs = 1;
5840 struct btrfs_bio *bbio = NULL;
5841
5842 length = bio->bi_iter.bi_size;
5843 map_length = length;
5844
5845 btrfs_bio_counter_inc_blocked(root->fs_info);
5846 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
5847 mirror_num, 1);
5848 if (ret) {
5849 btrfs_bio_counter_dec(root->fs_info);
5850 return ret;
5851 }
5852
5853 total_devs = bbio->num_stripes;
5854 bbio->orig_bio = first_bio;
5855 bbio->private = first_bio->bi_private;
5856 bbio->end_io = first_bio->bi_end_io;
5857 bbio->fs_info = root->fs_info;
5858 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
5859
5860 if (bbio->raid_map) {
5861 /* In this case, map_length has been set to the length of
5862 a single stripe; not the whole write */
5863 if (rw & WRITE) {
5864 ret = raid56_parity_write(root, bio, bbio, map_length);
5865 } else {
5866 ret = raid56_parity_recover(root, bio, bbio, map_length,
5867 mirror_num, 1);
5868 }
5869
5870 btrfs_bio_counter_dec(root->fs_info);
5871 return ret;
5872 }
5873
5874 if (map_length < length) {
5875 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
5876 logical, length, map_length);
5877 BUG();
5878 }
5879
5880 while (dev_nr < total_devs) {
5881 dev = bbio->stripes[dev_nr].dev;
5882 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
5883 bbio_error(bbio, first_bio, logical);
5884 dev_nr++;
5885 continue;
5886 }
5887
5888 /*
5889 * Check and see if we're ok with this bio based on it's size
5890 * and offset with the given device.
5891 */
5892 if (!bio_size_ok(dev->bdev, first_bio,
5893 bbio->stripes[dev_nr].physical >> 9)) {
5894 ret = breakup_stripe_bio(root, bbio, first_bio, dev,
5895 dev_nr, rw, async_submit);
5896 BUG_ON(ret);
5897 dev_nr++;
5898 continue;
5899 }
5900
5901 if (dev_nr < total_devs - 1) {
5902 bio = btrfs_bio_clone(first_bio, GFP_NOFS);
5903 BUG_ON(!bio); /* -ENOMEM */
5904 } else {
5905 bio = first_bio;
5906 bbio->flags |= BTRFS_BIO_ORIG_BIO_SUBMITTED;
5907 }
5908
5909 submit_stripe_bio(root, bbio, bio,
5910 bbio->stripes[dev_nr].physical, dev_nr, rw,
5911 async_submit);
5912 dev_nr++;
5913 }
5914 btrfs_bio_counter_dec(root->fs_info);
5915 return 0;
5916 }
5917
5918 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
5919 u8 *uuid, u8 *fsid)
5920 {
5921 struct btrfs_device *device;
5922 struct btrfs_fs_devices *cur_devices;
5923
5924 cur_devices = fs_info->fs_devices;
5925 while (cur_devices) {
5926 if (!fsid ||
5927 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
5928 device = __find_device(&cur_devices->devices,
5929 devid, uuid);
5930 if (device)
5931 return device;
5932 }
5933 cur_devices = cur_devices->seed;
5934 }
5935 return NULL;
5936 }
5937
5938 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
5939 struct btrfs_fs_devices *fs_devices,
5940 u64 devid, u8 *dev_uuid)
5941 {
5942 struct btrfs_device *device;
5943
5944 device = btrfs_alloc_device(NULL, &devid, dev_uuid);
5945 if (IS_ERR(device))
5946 return NULL;
5947
5948 list_add(&device->dev_list, &fs_devices->devices);
5949 device->fs_devices = fs_devices;
5950 fs_devices->num_devices++;
5951
5952 device->missing = 1;
5953 fs_devices->missing_devices++;
5954
5955 return device;
5956 }
5957
5958 /**
5959 * btrfs_alloc_device - allocate struct btrfs_device
5960 * @fs_info: used only for generating a new devid, can be NULL if
5961 * devid is provided (i.e. @devid != NULL).
5962 * @devid: a pointer to devid for this device. If NULL a new devid
5963 * is generated.
5964 * @uuid: a pointer to UUID for this device. If NULL a new UUID
5965 * is generated.
5966 *
5967 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
5968 * on error. Returned struct is not linked onto any lists and can be
5969 * destroyed with kfree() right away.
5970 */
5971 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
5972 const u64 *devid,
5973 const u8 *uuid)
5974 {
5975 struct btrfs_device *dev;
5976 u64 tmp;
5977
5978 if (WARN_ON(!devid && !fs_info))
5979 return ERR_PTR(-EINVAL);
5980
5981 dev = __alloc_device();
5982 if (IS_ERR(dev))
5983 return dev;
5984
5985 if (devid)
5986 tmp = *devid;
5987 else {
5988 int ret;
5989
5990 ret = find_next_devid(fs_info, &tmp);
5991 if (ret) {
5992 kfree(dev);
5993 return ERR_PTR(ret);
5994 }
5995 }
5996 dev->devid = tmp;
5997
5998 if (uuid)
5999 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
6000 else
6001 generate_random_uuid(dev->uuid);
6002
6003 btrfs_init_work(&dev->work, btrfs_submit_helper,
6004 pending_bios_fn, NULL, NULL);
6005
6006 return dev;
6007 }
6008
6009 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
6010 struct extent_buffer *leaf,
6011 struct btrfs_chunk *chunk)
6012 {
6013 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
6014 struct map_lookup *map;
6015 struct extent_map *em;
6016 u64 logical;
6017 u64 length;
6018 u64 devid;
6019 u8 uuid[BTRFS_UUID_SIZE];
6020 int num_stripes;
6021 int ret;
6022 int i;
6023
6024 logical = key->offset;
6025 length = btrfs_chunk_length(leaf, chunk);
6026
6027 read_lock(&map_tree->map_tree.lock);
6028 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
6029 read_unlock(&map_tree->map_tree.lock);
6030
6031 /* already mapped? */
6032 if (em && em->start <= logical && em->start + em->len > logical) {
6033 free_extent_map(em);
6034 return 0;
6035 } else if (em) {
6036 free_extent_map(em);
6037 }
6038
6039 em = alloc_extent_map();
6040 if (!em)
6041 return -ENOMEM;
6042 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
6043 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
6044 if (!map) {
6045 free_extent_map(em);
6046 return -ENOMEM;
6047 }
6048
6049 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
6050 em->bdev = (struct block_device *)map;
6051 em->start = logical;
6052 em->len = length;
6053 em->orig_start = 0;
6054 em->block_start = 0;
6055 em->block_len = em->len;
6056
6057 map->num_stripes = num_stripes;
6058 map->io_width = btrfs_chunk_io_width(leaf, chunk);
6059 map->io_align = btrfs_chunk_io_align(leaf, chunk);
6060 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
6061 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6062 map->type = btrfs_chunk_type(leaf, chunk);
6063 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
6064 for (i = 0; i < num_stripes; i++) {
6065 map->stripes[i].physical =
6066 btrfs_stripe_offset_nr(leaf, chunk, i);
6067 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
6068 read_extent_buffer(leaf, uuid, (unsigned long)
6069 btrfs_stripe_dev_uuid_nr(chunk, i),
6070 BTRFS_UUID_SIZE);
6071 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
6072 uuid, NULL);
6073 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
6074 free_extent_map(em);
6075 return -EIO;
6076 }
6077 if (!map->stripes[i].dev) {
6078 map->stripes[i].dev =
6079 add_missing_dev(root, root->fs_info->fs_devices,
6080 devid, uuid);
6081 if (!map->stripes[i].dev) {
6082 free_extent_map(em);
6083 return -EIO;
6084 }
6085 }
6086 map->stripes[i].dev->in_fs_metadata = 1;
6087 }
6088
6089 write_lock(&map_tree->map_tree.lock);
6090 ret = add_extent_mapping(&map_tree->map_tree, em, 0);
6091 write_unlock(&map_tree->map_tree.lock);
6092 BUG_ON(ret); /* Tree corruption */
6093 free_extent_map(em);
6094
6095 return 0;
6096 }
6097
6098 static void fill_device_from_item(struct extent_buffer *leaf,
6099 struct btrfs_dev_item *dev_item,
6100 struct btrfs_device *device)
6101 {
6102 unsigned long ptr;
6103
6104 device->devid = btrfs_device_id(leaf, dev_item);
6105 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
6106 device->total_bytes = device->disk_total_bytes;
6107 device->commit_total_bytes = device->disk_total_bytes;
6108 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
6109 device->commit_bytes_used = device->bytes_used;
6110 device->type = btrfs_device_type(leaf, dev_item);
6111 device->io_align = btrfs_device_io_align(leaf, dev_item);
6112 device->io_width = btrfs_device_io_width(leaf, dev_item);
6113 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
6114 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
6115 device->is_tgtdev_for_dev_replace = 0;
6116
6117 ptr = btrfs_device_uuid(dev_item);
6118 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
6119 }
6120
6121 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_root *root,
6122 u8 *fsid)
6123 {
6124 struct btrfs_fs_devices *fs_devices;
6125 int ret;
6126
6127 BUG_ON(!mutex_is_locked(&uuid_mutex));
6128
6129 fs_devices = root->fs_info->fs_devices->seed;
6130 while (fs_devices) {
6131 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE))
6132 return fs_devices;
6133
6134 fs_devices = fs_devices->seed;
6135 }
6136
6137 fs_devices = find_fsid(fsid);
6138 if (!fs_devices) {
6139 if (!btrfs_test_opt(root, DEGRADED))
6140 return ERR_PTR(-ENOENT);
6141
6142 fs_devices = alloc_fs_devices(fsid);
6143 if (IS_ERR(fs_devices))
6144 return fs_devices;
6145
6146 fs_devices->seeding = 1;
6147 fs_devices->opened = 1;
6148 return fs_devices;
6149 }
6150
6151 fs_devices = clone_fs_devices(fs_devices);
6152 if (IS_ERR(fs_devices))
6153 return fs_devices;
6154
6155 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
6156 root->fs_info->bdev_holder);
6157 if (ret) {
6158 free_fs_devices(fs_devices);
6159 fs_devices = ERR_PTR(ret);
6160 goto out;
6161 }
6162
6163 if (!fs_devices->seeding) {
6164 __btrfs_close_devices(fs_devices);
6165 free_fs_devices(fs_devices);
6166 fs_devices = ERR_PTR(-EINVAL);
6167 goto out;
6168 }
6169
6170 fs_devices->seed = root->fs_info->fs_devices->seed;
6171 root->fs_info->fs_devices->seed = fs_devices;
6172 out:
6173 return fs_devices;
6174 }
6175
6176 static int read_one_dev(struct btrfs_root *root,
6177 struct extent_buffer *leaf,
6178 struct btrfs_dev_item *dev_item)
6179 {
6180 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6181 struct btrfs_device *device;
6182 u64 devid;
6183 int ret;
6184 u8 fs_uuid[BTRFS_UUID_SIZE];
6185 u8 dev_uuid[BTRFS_UUID_SIZE];
6186
6187 devid = btrfs_device_id(leaf, dev_item);
6188 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
6189 BTRFS_UUID_SIZE);
6190 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
6191 BTRFS_UUID_SIZE);
6192
6193 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
6194 fs_devices = open_seed_devices(root, fs_uuid);
6195 if (IS_ERR(fs_devices))
6196 return PTR_ERR(fs_devices);
6197 }
6198
6199 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
6200 if (!device) {
6201 if (!btrfs_test_opt(root, DEGRADED))
6202 return -EIO;
6203
6204 btrfs_warn(root->fs_info, "devid %llu missing", devid);
6205 device = add_missing_dev(root, fs_devices, devid, dev_uuid);
6206 if (!device)
6207 return -ENOMEM;
6208 } else {
6209 if (!device->bdev && !btrfs_test_opt(root, DEGRADED))
6210 return -EIO;
6211
6212 if(!device->bdev && !device->missing) {
6213 /*
6214 * this happens when a device that was properly setup
6215 * in the device info lists suddenly goes bad.
6216 * device->bdev is NULL, and so we have to set
6217 * device->missing to one here
6218 */
6219 device->fs_devices->missing_devices++;
6220 device->missing = 1;
6221 }
6222
6223 /* Move the device to its own fs_devices */
6224 if (device->fs_devices != fs_devices) {
6225 ASSERT(device->missing);
6226
6227 list_move(&device->dev_list, &fs_devices->devices);
6228 device->fs_devices->num_devices--;
6229 fs_devices->num_devices++;
6230
6231 device->fs_devices->missing_devices--;
6232 fs_devices->missing_devices++;
6233
6234 device->fs_devices = fs_devices;
6235 }
6236 }
6237
6238 if (device->fs_devices != root->fs_info->fs_devices) {
6239 BUG_ON(device->writeable);
6240 if (device->generation !=
6241 btrfs_device_generation(leaf, dev_item))
6242 return -EINVAL;
6243 }
6244
6245 fill_device_from_item(leaf, dev_item, device);
6246 device->in_fs_metadata = 1;
6247 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
6248 device->fs_devices->total_rw_bytes += device->total_bytes;
6249 spin_lock(&root->fs_info->free_chunk_lock);
6250 root->fs_info->free_chunk_space += device->total_bytes -
6251 device->bytes_used;
6252 spin_unlock(&root->fs_info->free_chunk_lock);
6253 }
6254 ret = 0;
6255 return ret;
6256 }
6257
6258 int btrfs_read_sys_array(struct btrfs_root *root)
6259 {
6260 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
6261 struct extent_buffer *sb;
6262 struct btrfs_disk_key *disk_key;
6263 struct btrfs_chunk *chunk;
6264 u8 *array_ptr;
6265 unsigned long sb_array_offset;
6266 int ret = 0;
6267 u32 num_stripes;
6268 u32 array_size;
6269 u32 len = 0;
6270 u32 cur_offset;
6271 struct btrfs_key key;
6272
6273 ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
6274 /*
6275 * This will create extent buffer of nodesize, superblock size is
6276 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
6277 * overallocate but we can keep it as-is, only the first page is used.
6278 */
6279 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
6280 if (!sb)
6281 return -ENOMEM;
6282 btrfs_set_buffer_uptodate(sb);
6283 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
6284 /*
6285 * The sb extent buffer is artifical and just used to read the system array.
6286 * btrfs_set_buffer_uptodate() call does not properly mark all it's
6287 * pages up-to-date when the page is larger: extent does not cover the
6288 * whole page and consequently check_page_uptodate does not find all
6289 * the page's extents up-to-date (the hole beyond sb),
6290 * write_extent_buffer then triggers a WARN_ON.
6291 *
6292 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
6293 * but sb spans only this function. Add an explicit SetPageUptodate call
6294 * to silence the warning eg. on PowerPC 64.
6295 */
6296 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
6297 SetPageUptodate(sb->pages[0]);
6298
6299 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
6300 array_size = btrfs_super_sys_array_size(super_copy);
6301
6302 array_ptr = super_copy->sys_chunk_array;
6303 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
6304 cur_offset = 0;
6305
6306 while (cur_offset < array_size) {
6307 disk_key = (struct btrfs_disk_key *)array_ptr;
6308 len = sizeof(*disk_key);
6309 if (cur_offset + len > array_size)
6310 goto out_short_read;
6311
6312 btrfs_disk_key_to_cpu(&key, disk_key);
6313
6314 array_ptr += len;
6315 sb_array_offset += len;
6316 cur_offset += len;
6317
6318 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6319 chunk = (struct btrfs_chunk *)sb_array_offset;
6320 /*
6321 * At least one btrfs_chunk with one stripe must be
6322 * present, exact stripe count check comes afterwards
6323 */
6324 len = btrfs_chunk_item_size(1);
6325 if (cur_offset + len > array_size)
6326 goto out_short_read;
6327
6328 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
6329 len = btrfs_chunk_item_size(num_stripes);
6330 if (cur_offset + len > array_size)
6331 goto out_short_read;
6332
6333 ret = read_one_chunk(root, &key, sb, chunk);
6334 if (ret)
6335 break;
6336 } else {
6337 ret = -EIO;
6338 break;
6339 }
6340 array_ptr += len;
6341 sb_array_offset += len;
6342 cur_offset += len;
6343 }
6344 free_extent_buffer(sb);
6345 return ret;
6346
6347 out_short_read:
6348 printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
6349 len, cur_offset);
6350 free_extent_buffer(sb);
6351 return -EIO;
6352 }
6353
6354 int btrfs_read_chunk_tree(struct btrfs_root *root)
6355 {
6356 struct btrfs_path *path;
6357 struct extent_buffer *leaf;
6358 struct btrfs_key key;
6359 struct btrfs_key found_key;
6360 int ret;
6361 int slot;
6362
6363 root = root->fs_info->chunk_root;
6364
6365 path = btrfs_alloc_path();
6366 if (!path)
6367 return -ENOMEM;
6368
6369 mutex_lock(&uuid_mutex);
6370 lock_chunks(root);
6371
6372 /*
6373 * Read all device items, and then all the chunk items. All
6374 * device items are found before any chunk item (their object id
6375 * is smaller than the lowest possible object id for a chunk
6376 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
6377 */
6378 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
6379 key.offset = 0;
6380 key.type = 0;
6381 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6382 if (ret < 0)
6383 goto error;
6384 while (1) {
6385 leaf = path->nodes[0];
6386 slot = path->slots[0];
6387 if (slot >= btrfs_header_nritems(leaf)) {
6388 ret = btrfs_next_leaf(root, path);
6389 if (ret == 0)
6390 continue;
6391 if (ret < 0)
6392 goto error;
6393 break;
6394 }
6395 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6396 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
6397 struct btrfs_dev_item *dev_item;
6398 dev_item = btrfs_item_ptr(leaf, slot,
6399 struct btrfs_dev_item);
6400 ret = read_one_dev(root, leaf, dev_item);
6401 if (ret)
6402 goto error;
6403 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
6404 struct btrfs_chunk *chunk;
6405 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
6406 ret = read_one_chunk(root, &found_key, leaf, chunk);
6407 if (ret)
6408 goto error;
6409 }
6410 path->slots[0]++;
6411 }
6412 ret = 0;
6413 error:
6414 unlock_chunks(root);
6415 mutex_unlock(&uuid_mutex);
6416
6417 btrfs_free_path(path);
6418 return ret;
6419 }
6420
6421 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
6422 {
6423 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6424 struct btrfs_device *device;
6425
6426 while (fs_devices) {
6427 mutex_lock(&fs_devices->device_list_mutex);
6428 list_for_each_entry(device, &fs_devices->devices, dev_list)
6429 device->dev_root = fs_info->dev_root;
6430 mutex_unlock(&fs_devices->device_list_mutex);
6431
6432 fs_devices = fs_devices->seed;
6433 }
6434 }
6435
6436 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
6437 {
6438 int i;
6439
6440 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6441 btrfs_dev_stat_reset(dev, i);
6442 }
6443
6444 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
6445 {
6446 struct btrfs_key key;
6447 struct btrfs_key found_key;
6448 struct btrfs_root *dev_root = fs_info->dev_root;
6449 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6450 struct extent_buffer *eb;
6451 int slot;
6452 int ret = 0;
6453 struct btrfs_device *device;
6454 struct btrfs_path *path = NULL;
6455 int i;
6456
6457 path = btrfs_alloc_path();
6458 if (!path) {
6459 ret = -ENOMEM;
6460 goto out;
6461 }
6462
6463 mutex_lock(&fs_devices->device_list_mutex);
6464 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6465 int item_size;
6466 struct btrfs_dev_stats_item *ptr;
6467
6468 key.objectid = 0;
6469 key.type = BTRFS_DEV_STATS_KEY;
6470 key.offset = device->devid;
6471 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
6472 if (ret) {
6473 __btrfs_reset_dev_stats(device);
6474 device->dev_stats_valid = 1;
6475 btrfs_release_path(path);
6476 continue;
6477 }
6478 slot = path->slots[0];
6479 eb = path->nodes[0];
6480 btrfs_item_key_to_cpu(eb, &found_key, slot);
6481 item_size = btrfs_item_size_nr(eb, slot);
6482
6483 ptr = btrfs_item_ptr(eb, slot,
6484 struct btrfs_dev_stats_item);
6485
6486 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6487 if (item_size >= (1 + i) * sizeof(__le64))
6488 btrfs_dev_stat_set(device, i,
6489 btrfs_dev_stats_value(eb, ptr, i));
6490 else
6491 btrfs_dev_stat_reset(device, i);
6492 }
6493
6494 device->dev_stats_valid = 1;
6495 btrfs_dev_stat_print_on_load(device);
6496 btrfs_release_path(path);
6497 }
6498 mutex_unlock(&fs_devices->device_list_mutex);
6499
6500 out:
6501 btrfs_free_path(path);
6502 return ret < 0 ? ret : 0;
6503 }
6504
6505 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
6506 struct btrfs_root *dev_root,
6507 struct btrfs_device *device)
6508 {
6509 struct btrfs_path *path;
6510 struct btrfs_key key;
6511 struct extent_buffer *eb;
6512 struct btrfs_dev_stats_item *ptr;
6513 int ret;
6514 int i;
6515
6516 key.objectid = 0;
6517 key.type = BTRFS_DEV_STATS_KEY;
6518 key.offset = device->devid;
6519
6520 path = btrfs_alloc_path();
6521 BUG_ON(!path);
6522 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
6523 if (ret < 0) {
6524 printk_in_rcu(KERN_WARNING "BTRFS: "
6525 "error %d while searching for dev_stats item for device %s!\n",
6526 ret, rcu_str_deref(device->name));
6527 goto out;
6528 }
6529
6530 if (ret == 0 &&
6531 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
6532 /* need to delete old one and insert a new one */
6533 ret = btrfs_del_item(trans, dev_root, path);
6534 if (ret != 0) {
6535 printk_in_rcu(KERN_WARNING "BTRFS: "
6536 "delete too small dev_stats item for device %s failed %d!\n",
6537 rcu_str_deref(device->name), ret);
6538 goto out;
6539 }
6540 ret = 1;
6541 }
6542
6543 if (ret == 1) {
6544 /* need to insert a new item */
6545 btrfs_release_path(path);
6546 ret = btrfs_insert_empty_item(trans, dev_root, path,
6547 &key, sizeof(*ptr));
6548 if (ret < 0) {
6549 printk_in_rcu(KERN_WARNING "BTRFS: "
6550 "insert dev_stats item for device %s failed %d!\n",
6551 rcu_str_deref(device->name), ret);
6552 goto out;
6553 }
6554 }
6555
6556 eb = path->nodes[0];
6557 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
6558 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6559 btrfs_set_dev_stats_value(eb, ptr, i,
6560 btrfs_dev_stat_read(device, i));
6561 btrfs_mark_buffer_dirty(eb);
6562
6563 out:
6564 btrfs_free_path(path);
6565 return ret;
6566 }
6567
6568 /*
6569 * called from commit_transaction. Writes all changed device stats to disk.
6570 */
6571 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
6572 struct btrfs_fs_info *fs_info)
6573 {
6574 struct btrfs_root *dev_root = fs_info->dev_root;
6575 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6576 struct btrfs_device *device;
6577 int stats_cnt;
6578 int ret = 0;
6579
6580 mutex_lock(&fs_devices->device_list_mutex);
6581 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6582 if (!device->dev_stats_valid || !btrfs_dev_stats_dirty(device))
6583 continue;
6584
6585 stats_cnt = atomic_read(&device->dev_stats_ccnt);
6586 ret = update_dev_stat_item(trans, dev_root, device);
6587 if (!ret)
6588 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
6589 }
6590 mutex_unlock(&fs_devices->device_list_mutex);
6591
6592 return ret;
6593 }
6594
6595 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
6596 {
6597 btrfs_dev_stat_inc(dev, index);
6598 btrfs_dev_stat_print_on_error(dev);
6599 }
6600
6601 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
6602 {
6603 if (!dev->dev_stats_valid)
6604 return;
6605 printk_ratelimited_in_rcu(KERN_ERR "BTRFS: "
6606 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6607 rcu_str_deref(dev->name),
6608 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6609 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6610 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6611 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6612 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6613 }
6614
6615 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
6616 {
6617 int i;
6618
6619 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6620 if (btrfs_dev_stat_read(dev, i) != 0)
6621 break;
6622 if (i == BTRFS_DEV_STAT_VALUES_MAX)
6623 return; /* all values == 0, suppress message */
6624
6625 printk_in_rcu(KERN_INFO "BTRFS: "
6626 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6627 rcu_str_deref(dev->name),
6628 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6629 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6630 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6631 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6632 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6633 }
6634
6635 int btrfs_get_dev_stats(struct btrfs_root *root,
6636 struct btrfs_ioctl_get_dev_stats *stats)
6637 {
6638 struct btrfs_device *dev;
6639 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6640 int i;
6641
6642 mutex_lock(&fs_devices->device_list_mutex);
6643 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
6644 mutex_unlock(&fs_devices->device_list_mutex);
6645
6646 if (!dev) {
6647 btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
6648 return -ENODEV;
6649 } else if (!dev->dev_stats_valid) {
6650 btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
6651 return -ENODEV;
6652 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
6653 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6654 if (stats->nr_items > i)
6655 stats->values[i] =
6656 btrfs_dev_stat_read_and_reset(dev, i);
6657 else
6658 btrfs_dev_stat_reset(dev, i);
6659 }
6660 } else {
6661 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6662 if (stats->nr_items > i)
6663 stats->values[i] = btrfs_dev_stat_read(dev, i);
6664 }
6665 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
6666 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
6667 return 0;
6668 }
6669
6670 int btrfs_scratch_superblock(struct btrfs_device *device)
6671 {
6672 struct buffer_head *bh;
6673 struct btrfs_super_block *disk_super;
6674
6675 bh = btrfs_read_dev_super(device->bdev);
6676 if (!bh)
6677 return -EINVAL;
6678 disk_super = (struct btrfs_super_block *)bh->b_data;
6679
6680 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
6681 set_buffer_dirty(bh);
6682 sync_dirty_buffer(bh);
6683 brelse(bh);
6684
6685 return 0;
6686 }
6687
6688 /*
6689 * Update the size of all devices, which is used for writing out the
6690 * super blocks.
6691 */
6692 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info)
6693 {
6694 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6695 struct btrfs_device *curr, *next;
6696
6697 if (list_empty(&fs_devices->resized_devices))
6698 return;
6699
6700 mutex_lock(&fs_devices->device_list_mutex);
6701 lock_chunks(fs_info->dev_root);
6702 list_for_each_entry_safe(curr, next, &fs_devices->resized_devices,
6703 resized_list) {
6704 list_del_init(&curr->resized_list);
6705 curr->commit_total_bytes = curr->disk_total_bytes;
6706 }
6707 unlock_chunks(fs_info->dev_root);
6708 mutex_unlock(&fs_devices->device_list_mutex);
6709 }
6710
6711 /* Must be invoked during the transaction commit */
6712 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
6713 struct btrfs_transaction *transaction)
6714 {
6715 struct extent_map *em;
6716 struct map_lookup *map;
6717 struct btrfs_device *dev;
6718 int i;
6719
6720 if (list_empty(&transaction->pending_chunks))
6721 return;
6722
6723 /* In order to kick the device replace finish process */
6724 lock_chunks(root);
6725 list_for_each_entry(em, &transaction->pending_chunks, list) {
6726 map = (struct map_lookup *)em->bdev;
6727
6728 for (i = 0; i < map->num_stripes; i++) {
6729 dev = map->stripes[i].dev;
6730 dev->commit_bytes_used = dev->bytes_used;
6731 }
6732 }
6733 unlock_chunks(root);
6734 }
Linux with added FPC-III support