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irqchip/zevio: Use irq_data_get_chip_type() helper
[linux/fpc-iii.git] / fs / btrfs / volumes.c
blob45645220660996773b1f76cd1d526d4aeae33dac
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 const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
46 [BTRFS_RAID_RAID10] = {
47 .sub_stripes = 2,
48 .dev_stripes = 1,
49 .devs_max = 0, /* 0 == as many as possible */
50 .devs_min = 4,
51 .tolerated_failures = 1,
52 .devs_increment = 2,
53 .ncopies = 2,
54 },
55 [BTRFS_RAID_RAID1] = {
56 .sub_stripes = 1,
57 .dev_stripes = 1,
58 .devs_max = 2,
59 .devs_min = 2,
60 .tolerated_failures = 1,
61 .devs_increment = 2,
62 .ncopies = 2,
63 },
64 [BTRFS_RAID_DUP] = {
65 .sub_stripes = 1,
66 .dev_stripes = 2,
67 .devs_max = 1,
68 .devs_min = 1,
69 .tolerated_failures = 0,
70 .devs_increment = 1,
71 .ncopies = 2,
72 },
73 [BTRFS_RAID_RAID0] = {
74 .sub_stripes = 1,
75 .dev_stripes = 1,
76 .devs_max = 0,
77 .devs_min = 2,
78 .tolerated_failures = 0,
79 .devs_increment = 1,
80 .ncopies = 1,
81 },
82 [BTRFS_RAID_SINGLE] = {
83 .sub_stripes = 1,
84 .dev_stripes = 1,
85 .devs_max = 1,
86 .devs_min = 1,
87 .tolerated_failures = 0,
88 .devs_increment = 1,
89 .ncopies = 1,
90 },
91 [BTRFS_RAID_RAID5] = {
92 .sub_stripes = 1,
93 .dev_stripes = 1,
94 .devs_max = 0,
95 .devs_min = 2,
96 .tolerated_failures = 1,
97 .devs_increment = 1,
98 .ncopies = 2,
99 },
100 [BTRFS_RAID_RAID6] = {
101 .sub_stripes = 1,
102 .dev_stripes = 1,
103 .devs_max = 0,
104 .devs_min = 3,
105 .tolerated_failures = 2,
106 .devs_increment = 1,
107 .ncopies = 3,
108 },
109 };
110
111 const u64 const btrfs_raid_group[BTRFS_NR_RAID_TYPES] = {
112 [BTRFS_RAID_RAID10] = BTRFS_BLOCK_GROUP_RAID10,
113 [BTRFS_RAID_RAID1] = BTRFS_BLOCK_GROUP_RAID1,
114 [BTRFS_RAID_DUP] = BTRFS_BLOCK_GROUP_DUP,
115 [BTRFS_RAID_RAID0] = BTRFS_BLOCK_GROUP_RAID0,
116 [BTRFS_RAID_SINGLE] = 0,
117 [BTRFS_RAID_RAID5] = BTRFS_BLOCK_GROUP_RAID5,
118 [BTRFS_RAID_RAID6] = BTRFS_BLOCK_GROUP_RAID6,
119 };
120
121 static int init_first_rw_device(struct btrfs_trans_handle *trans,
122 struct btrfs_root *root,
123 struct btrfs_device *device);
124 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
125 static void __btrfs_reset_dev_stats(struct btrfs_device *dev);
126 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev);
127 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
128
129 DEFINE_MUTEX(uuid_mutex);
130 static LIST_HEAD(fs_uuids);
131 struct list_head *btrfs_get_fs_uuids(void)
132 {
133 return &fs_uuids;
134 }
135
136 static struct btrfs_fs_devices *__alloc_fs_devices(void)
137 {
138 struct btrfs_fs_devices *fs_devs;
139
140 fs_devs = kzalloc(sizeof(*fs_devs), GFP_NOFS);
141 if (!fs_devs)
142 return ERR_PTR(-ENOMEM);
143
144 mutex_init(&fs_devs->device_list_mutex);
145
146 INIT_LIST_HEAD(&fs_devs->devices);
147 INIT_LIST_HEAD(&fs_devs->resized_devices);
148 INIT_LIST_HEAD(&fs_devs->alloc_list);
149 INIT_LIST_HEAD(&fs_devs->list);
150
151 return fs_devs;
152 }
153
154 /**
155 * alloc_fs_devices - allocate struct btrfs_fs_devices
156 * @fsid: a pointer to UUID for this FS. If NULL a new UUID is
157 * generated.
158 *
159 * Return: a pointer to a new &struct btrfs_fs_devices on success;
160 * ERR_PTR() on error. Returned struct is not linked onto any lists and
161 * can be destroyed with kfree() right away.
162 */
163 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
164 {
165 struct btrfs_fs_devices *fs_devs;
166
167 fs_devs = __alloc_fs_devices();
168 if (IS_ERR(fs_devs))
169 return fs_devs;
170
171 if (fsid)
172 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
173 else
174 generate_random_uuid(fs_devs->fsid);
175
176 return fs_devs;
177 }
178
179 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
180 {
181 struct btrfs_device *device;
182 WARN_ON(fs_devices->opened);
183 while (!list_empty(&fs_devices->devices)) {
184 device = list_entry(fs_devices->devices.next,
185 struct btrfs_device, dev_list);
186 list_del(&device->dev_list);
187 rcu_string_free(device->name);
188 kfree(device);
189 }
190 kfree(fs_devices);
191 }
192
193 static void btrfs_kobject_uevent(struct block_device *bdev,
194 enum kobject_action action)
195 {
196 int ret;
197
198 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
199 if (ret)
200 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
201 action,
202 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
203 &disk_to_dev(bdev->bd_disk)->kobj);
204 }
205
206 void btrfs_cleanup_fs_uuids(void)
207 {
208 struct btrfs_fs_devices *fs_devices;
209
210 while (!list_empty(&fs_uuids)) {
211 fs_devices = list_entry(fs_uuids.next,
212 struct btrfs_fs_devices, list);
213 list_del(&fs_devices->list);
214 free_fs_devices(fs_devices);
215 }
216 }
217
218 static struct btrfs_device *__alloc_device(void)
219 {
220 struct btrfs_device *dev;
221
222 dev = kzalloc(sizeof(*dev), GFP_NOFS);
223 if (!dev)
224 return ERR_PTR(-ENOMEM);
225
226 INIT_LIST_HEAD(&dev->dev_list);
227 INIT_LIST_HEAD(&dev->dev_alloc_list);
228 INIT_LIST_HEAD(&dev->resized_list);
229
230 spin_lock_init(&dev->io_lock);
231
232 spin_lock_init(&dev->reada_lock);
233 atomic_set(&dev->reada_in_flight, 0);
234 atomic_set(&dev->dev_stats_ccnt, 0);
235 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
236 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
237
238 return dev;
239 }
240
241 static noinline struct btrfs_device *__find_device(struct list_head *head,
242 u64 devid, u8 *uuid)
243 {
244 struct btrfs_device *dev;
245
246 list_for_each_entry(dev, head, dev_list) {
247 if (dev->devid == devid &&
248 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
249 return dev;
250 }
251 }
252 return NULL;
253 }
254
255 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
256 {
257 struct btrfs_fs_devices *fs_devices;
258
259 list_for_each_entry(fs_devices, &fs_uuids, list) {
260 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
261 return fs_devices;
262 }
263 return NULL;
264 }
265
266 static int
267 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
268 int flush, struct block_device **bdev,
269 struct buffer_head **bh)
270 {
271 int ret;
272
273 *bdev = blkdev_get_by_path(device_path, flags, holder);
274
275 if (IS_ERR(*bdev)) {
276 ret = PTR_ERR(*bdev);
277 goto error;
278 }
279
280 if (flush)
281 filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
282 ret = set_blocksize(*bdev, 4096);
283 if (ret) {
284 blkdev_put(*bdev, flags);
285 goto error;
286 }
287 invalidate_bdev(*bdev);
288 *bh = btrfs_read_dev_super(*bdev);
289 if (IS_ERR(*bh)) {
290 ret = PTR_ERR(*bh);
291 blkdev_put(*bdev, flags);
292 goto error;
293 }
294
295 return 0;
296
297 error:
298 *bdev = NULL;
299 *bh = NULL;
300 return ret;
301 }
302
303 static void requeue_list(struct btrfs_pending_bios *pending_bios,
304 struct bio *head, struct bio *tail)
305 {
306
307 struct bio *old_head;
308
309 old_head = pending_bios->head;
310 pending_bios->head = head;
311 if (pending_bios->tail)
312 tail->bi_next = old_head;
313 else
314 pending_bios->tail = tail;
315 }
316
317 /*
318 * we try to collect pending bios for a device so we don't get a large
319 * number of procs sending bios down to the same device. This greatly
320 * improves the schedulers ability to collect and merge the bios.
321 *
322 * But, it also turns into a long list of bios to process and that is sure
323 * to eventually make the worker thread block. The solution here is to
324 * make some progress and then put this work struct back at the end of
325 * the list if the block device is congested. This way, multiple devices
326 * can make progress from a single worker thread.
327 */
328 static noinline void run_scheduled_bios(struct btrfs_device *device)
329 {
330 struct bio *pending;
331 struct backing_dev_info *bdi;
332 struct btrfs_fs_info *fs_info;
333 struct btrfs_pending_bios *pending_bios;
334 struct bio *tail;
335 struct bio *cur;
336 int again = 0;
337 unsigned long num_run;
338 unsigned long batch_run = 0;
339 unsigned long limit;
340 unsigned long last_waited = 0;
341 int force_reg = 0;
342 int sync_pending = 0;
343 struct blk_plug plug;
344
345 /*
346 * this function runs all the bios we've collected for
347 * a particular device. We don't want to wander off to
348 * another device without first sending all of these down.
349 * So, setup a plug here and finish it off before we return
350 */
351 blk_start_plug(&plug);
352
353 bdi = blk_get_backing_dev_info(device->bdev);
354 fs_info = device->dev_root->fs_info;
355 limit = btrfs_async_submit_limit(fs_info);
356 limit = limit * 2 / 3;
357
358 loop:
359 spin_lock(&device->io_lock);
360
361 loop_lock:
362 num_run = 0;
363
364 /* take all the bios off the list at once and process them
365 * later on (without the lock held). But, remember the
366 * tail and other pointers so the bios can be properly reinserted
367 * into the list if we hit congestion
368 */
369 if (!force_reg && device->pending_sync_bios.head) {
370 pending_bios = &device->pending_sync_bios;
371 force_reg = 1;
372 } else {
373 pending_bios = &device->pending_bios;
374 force_reg = 0;
375 }
376
377 pending = pending_bios->head;
378 tail = pending_bios->tail;
379 WARN_ON(pending && !tail);
380
381 /*
382 * if pending was null this time around, no bios need processing
383 * at all and we can stop. Otherwise it'll loop back up again
384 * and do an additional check so no bios are missed.
385 *
386 * device->running_pending is used to synchronize with the
387 * schedule_bio code.
388 */
389 if (device->pending_sync_bios.head == NULL &&
390 device->pending_bios.head == NULL) {
391 again = 0;
392 device->running_pending = 0;
393 } else {
394 again = 1;
395 device->running_pending = 1;
396 }
397
398 pending_bios->head = NULL;
399 pending_bios->tail = NULL;
400
401 spin_unlock(&device->io_lock);
402
403 while (pending) {
404
405 rmb();
406 /* we want to work on both lists, but do more bios on the
407 * sync list than the regular list
408 */
409 if ((num_run > 32 &&
410 pending_bios != &device->pending_sync_bios &&
411 device->pending_sync_bios.head) ||
412 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
413 device->pending_bios.head)) {
414 spin_lock(&device->io_lock);
415 requeue_list(pending_bios, pending, tail);
416 goto loop_lock;
417 }
418
419 cur = pending;
420 pending = pending->bi_next;
421 cur->bi_next = NULL;
422
423 /*
424 * atomic_dec_return implies a barrier for waitqueue_active
425 */
426 if (atomic_dec_return(&fs_info->nr_async_bios) < limit &&
427 waitqueue_active(&fs_info->async_submit_wait))
428 wake_up(&fs_info->async_submit_wait);
429
430 BUG_ON(atomic_read(&cur->__bi_cnt) == 0);
431
432 /*
433 * if we're doing the sync list, record that our
434 * plug has some sync requests on it
435 *
436 * If we're doing the regular list and there are
437 * sync requests sitting around, unplug before
438 * we add more
439 */
440 if (pending_bios == &device->pending_sync_bios) {
441 sync_pending = 1;
442 } else if (sync_pending) {
443 blk_finish_plug(&plug);
444 blk_start_plug(&plug);
445 sync_pending = 0;
446 }
447
448 btrfsic_submit_bio(cur->bi_rw, cur);
449 num_run++;
450 batch_run++;
451
452 cond_resched();
453
454 /*
455 * we made progress, there is more work to do and the bdi
456 * is now congested. Back off and let other work structs
457 * run instead
458 */
459 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
460 fs_info->fs_devices->open_devices > 1) {
461 struct io_context *ioc;
462
463 ioc = current->io_context;
464
465 /*
466 * the main goal here is that we don't want to
467 * block if we're going to be able to submit
468 * more requests without blocking.
469 *
470 * This code does two great things, it pokes into
471 * the elevator code from a filesystem _and_
472 * it makes assumptions about how batching works.
473 */
474 if (ioc && ioc->nr_batch_requests > 0 &&
475 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
476 (last_waited == 0 ||
477 ioc->last_waited == last_waited)) {
478 /*
479 * we want to go through our batch of
480 * requests and stop. So, we copy out
481 * the ioc->last_waited time and test
482 * against it before looping
483 */
484 last_waited = ioc->last_waited;
485 cond_resched();
486 continue;
487 }
488 spin_lock(&device->io_lock);
489 requeue_list(pending_bios, pending, tail);
490 device->running_pending = 1;
491
492 spin_unlock(&device->io_lock);
493 btrfs_queue_work(fs_info->submit_workers,
494 &device->work);
495 goto done;
496 }
497 /* unplug every 64 requests just for good measure */
498 if (batch_run % 64 == 0) {
499 blk_finish_plug(&plug);
500 blk_start_plug(&plug);
501 sync_pending = 0;
502 }
503 }
504
505 cond_resched();
506 if (again)
507 goto loop;
508
509 spin_lock(&device->io_lock);
510 if (device->pending_bios.head || device->pending_sync_bios.head)
511 goto loop_lock;
512 spin_unlock(&device->io_lock);
513
514 done:
515 blk_finish_plug(&plug);
516 }
517
518 static void pending_bios_fn(struct btrfs_work *work)
519 {
520 struct btrfs_device *device;
521
522 device = container_of(work, struct btrfs_device, work);
523 run_scheduled_bios(device);
524 }
525
526
527 void btrfs_free_stale_device(struct btrfs_device *cur_dev)
528 {
529 struct btrfs_fs_devices *fs_devs;
530 struct btrfs_device *dev;
531
532 if (!cur_dev->name)
533 return;
534
535 list_for_each_entry(fs_devs, &fs_uuids, list) {
536 int del = 1;
537
538 if (fs_devs->opened)
539 continue;
540 if (fs_devs->seeding)
541 continue;
542
543 list_for_each_entry(dev, &fs_devs->devices, dev_list) {
544
545 if (dev == cur_dev)
546 continue;
547 if (!dev->name)
548 continue;
549
550 /*
551 * Todo: This won't be enough. What if the same device
552 * comes back (with new uuid and) with its mapper path?
553 * But for now, this does help as mostly an admin will
554 * either use mapper or non mapper path throughout.
555 */
556 rcu_read_lock();
557 del = strcmp(rcu_str_deref(dev->name),
558 rcu_str_deref(cur_dev->name));
559 rcu_read_unlock();
560 if (!del)
561 break;
562 }
563
564 if (!del) {
565 /* delete the stale device */
566 if (fs_devs->num_devices == 1) {
567 btrfs_sysfs_remove_fsid(fs_devs);
568 list_del(&fs_devs->list);
569 free_fs_devices(fs_devs);
570 } else {
571 fs_devs->num_devices--;
572 list_del(&dev->dev_list);
573 rcu_string_free(dev->name);
574 kfree(dev);
575 }
576 break;
577 }
578 }
579 }
580
581 /*
582 * Add new device to list of registered devices
583 *
584 * Returns:
585 * 1 - first time device is seen
586 * 0 - device already known
587 * < 0 - error
588 */
589 static noinline int device_list_add(const char *path,
590 struct btrfs_super_block *disk_super,
591 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
592 {
593 struct btrfs_device *device;
594 struct btrfs_fs_devices *fs_devices;
595 struct rcu_string *name;
596 int ret = 0;
597 u64 found_transid = btrfs_super_generation(disk_super);
598
599 fs_devices = find_fsid(disk_super->fsid);
600 if (!fs_devices) {
601 fs_devices = alloc_fs_devices(disk_super->fsid);
602 if (IS_ERR(fs_devices))
603 return PTR_ERR(fs_devices);
604
605 list_add(&fs_devices->list, &fs_uuids);
606
607 device = NULL;
608 } else {
609 device = __find_device(&fs_devices->devices, devid,
610 disk_super->dev_item.uuid);
611 }
612
613 if (!device) {
614 if (fs_devices->opened)
615 return -EBUSY;
616
617 device = btrfs_alloc_device(NULL, &devid,
618 disk_super->dev_item.uuid);
619 if (IS_ERR(device)) {
620 /* we can safely leave the fs_devices entry around */
621 return PTR_ERR(device);
622 }
623
624 name = rcu_string_strdup(path, GFP_NOFS);
625 if (!name) {
626 kfree(device);
627 return -ENOMEM;
628 }
629 rcu_assign_pointer(device->name, name);
630
631 mutex_lock(&fs_devices->device_list_mutex);
632 list_add_rcu(&device->dev_list, &fs_devices->devices);
633 fs_devices->num_devices++;
634 mutex_unlock(&fs_devices->device_list_mutex);
635
636 ret = 1;
637 device->fs_devices = fs_devices;
638 } else if (!device->name || strcmp(device->name->str, path)) {
639 /*
640 * When FS is already mounted.
641 * 1. If you are here and if the device->name is NULL that
642 * means this device was missing at time of FS mount.
643 * 2. If you are here and if the device->name is different
644 * from 'path' that means either
645 * a. The same device disappeared and reappeared with
646 * different name. or
647 * b. The missing-disk-which-was-replaced, has
648 * reappeared now.
649 *
650 * We must allow 1 and 2a above. But 2b would be a spurious
651 * and unintentional.
652 *
653 * Further in case of 1 and 2a above, the disk at 'path'
654 * would have missed some transaction when it was away and
655 * in case of 2a the stale bdev has to be updated as well.
656 * 2b must not be allowed at all time.
657 */
658
659 /*
660 * For now, we do allow update to btrfs_fs_device through the
661 * btrfs dev scan cli after FS has been mounted. We're still
662 * tracking a problem where systems fail mount by subvolume id
663 * when we reject replacement on a mounted FS.
664 */
665 if (!fs_devices->opened && found_transid < device->generation) {
666 /*
667 * That is if the FS is _not_ mounted and if you
668 * are here, that means there is more than one
669 * disk with same uuid and devid.We keep the one
670 * with larger generation number or the last-in if
671 * generation are equal.
672 */
673 return -EEXIST;
674 }
675
676 name = rcu_string_strdup(path, GFP_NOFS);
677 if (!name)
678 return -ENOMEM;
679 rcu_string_free(device->name);
680 rcu_assign_pointer(device->name, name);
681 if (device->missing) {
682 fs_devices->missing_devices--;
683 device->missing = 0;
684 }
685 }
686
687 /*
688 * Unmount does not free the btrfs_device struct but would zero
689 * generation along with most of the other members. So just update
690 * it back. We need it to pick the disk with largest generation
691 * (as above).
692 */
693 if (!fs_devices->opened)
694 device->generation = found_transid;
695
696 /*
697 * if there is new btrfs on an already registered device,
698 * then remove the stale device entry.
699 */
700 btrfs_free_stale_device(device);
701
702 *fs_devices_ret = fs_devices;
703
704 return ret;
705 }
706
707 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
708 {
709 struct btrfs_fs_devices *fs_devices;
710 struct btrfs_device *device;
711 struct btrfs_device *orig_dev;
712
713 fs_devices = alloc_fs_devices(orig->fsid);
714 if (IS_ERR(fs_devices))
715 return fs_devices;
716
717 mutex_lock(&orig->device_list_mutex);
718 fs_devices->total_devices = orig->total_devices;
719
720 /* We have held the volume lock, it is safe to get the devices. */
721 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
722 struct rcu_string *name;
723
724 device = btrfs_alloc_device(NULL, &orig_dev->devid,
725 orig_dev->uuid);
726 if (IS_ERR(device))
727 goto error;
728
729 /*
730 * This is ok to do without rcu read locked because we hold the
731 * uuid mutex so nothing we touch in here is going to disappear.
732 */
733 if (orig_dev->name) {
734 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
735 if (!name) {
736 kfree(device);
737 goto error;
738 }
739 rcu_assign_pointer(device->name, name);
740 }
741
742 list_add(&device->dev_list, &fs_devices->devices);
743 device->fs_devices = fs_devices;
744 fs_devices->num_devices++;
745 }
746 mutex_unlock(&orig->device_list_mutex);
747 return fs_devices;
748 error:
749 mutex_unlock(&orig->device_list_mutex);
750 free_fs_devices(fs_devices);
751 return ERR_PTR(-ENOMEM);
752 }
753
754 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step)
755 {
756 struct btrfs_device *device, *next;
757 struct btrfs_device *latest_dev = NULL;
758
759 mutex_lock(&uuid_mutex);
760 again:
761 /* This is the initialized path, it is safe to release the devices. */
762 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
763 if (device->in_fs_metadata) {
764 if (!device->is_tgtdev_for_dev_replace &&
765 (!latest_dev ||
766 device->generation > latest_dev->generation)) {
767 latest_dev = device;
768 }
769 continue;
770 }
771
772 if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
773 /*
774 * In the first step, keep the device which has
775 * the correct fsid and the devid that is used
776 * for the dev_replace procedure.
777 * In the second step, the dev_replace state is
778 * read from the device tree and it is known
779 * whether the procedure is really active or
780 * not, which means whether this device is
781 * used or whether it should be removed.
782 */
783 if (step == 0 || device->is_tgtdev_for_dev_replace) {
784 continue;
785 }
786 }
787 if (device->bdev) {
788 blkdev_put(device->bdev, device->mode);
789 device->bdev = NULL;
790 fs_devices->open_devices--;
791 }
792 if (device->writeable) {
793 list_del_init(&device->dev_alloc_list);
794 device->writeable = 0;
795 if (!device->is_tgtdev_for_dev_replace)
796 fs_devices->rw_devices--;
797 }
798 list_del_init(&device->dev_list);
799 fs_devices->num_devices--;
800 rcu_string_free(device->name);
801 kfree(device);
802 }
803
804 if (fs_devices->seed) {
805 fs_devices = fs_devices->seed;
806 goto again;
807 }
808
809 fs_devices->latest_bdev = latest_dev->bdev;
810
811 mutex_unlock(&uuid_mutex);
812 }
813
814 static void __free_device(struct work_struct *work)
815 {
816 struct btrfs_device *device;
817
818 device = container_of(work, struct btrfs_device, rcu_work);
819
820 if (device->bdev)
821 blkdev_put(device->bdev, device->mode);
822
823 rcu_string_free(device->name);
824 kfree(device);
825 }
826
827 static void free_device(struct rcu_head *head)
828 {
829 struct btrfs_device *device;
830
831 device = container_of(head, struct btrfs_device, rcu);
832
833 INIT_WORK(&device->rcu_work, __free_device);
834 schedule_work(&device->rcu_work);
835 }
836
837 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
838 {
839 struct btrfs_device *device, *tmp;
840
841 if (--fs_devices->opened > 0)
842 return 0;
843
844 mutex_lock(&fs_devices->device_list_mutex);
845 list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list) {
846 btrfs_close_one_device(device);
847 }
848 mutex_unlock(&fs_devices->device_list_mutex);
849
850 WARN_ON(fs_devices->open_devices);
851 WARN_ON(fs_devices->rw_devices);
852 fs_devices->opened = 0;
853 fs_devices->seeding = 0;
854
855 return 0;
856 }
857
858 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
859 {
860 struct btrfs_fs_devices *seed_devices = NULL;
861 int ret;
862
863 mutex_lock(&uuid_mutex);
864 ret = __btrfs_close_devices(fs_devices);
865 if (!fs_devices->opened) {
866 seed_devices = fs_devices->seed;
867 fs_devices->seed = NULL;
868 }
869 mutex_unlock(&uuid_mutex);
870
871 while (seed_devices) {
872 fs_devices = seed_devices;
873 seed_devices = fs_devices->seed;
874 __btrfs_close_devices(fs_devices);
875 free_fs_devices(fs_devices);
876 }
877 /*
878 * Wait for rcu kworkers under __btrfs_close_devices
879 * to finish all blkdev_puts so device is really
880 * free when umount is done.
881 */
882 rcu_barrier();
883 return ret;
884 }
885
886 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
887 fmode_t flags, void *holder)
888 {
889 struct request_queue *q;
890 struct block_device *bdev;
891 struct list_head *head = &fs_devices->devices;
892 struct btrfs_device *device;
893 struct btrfs_device *latest_dev = NULL;
894 struct buffer_head *bh;
895 struct btrfs_super_block *disk_super;
896 u64 devid;
897 int seeding = 1;
898 int ret = 0;
899
900 flags |= FMODE_EXCL;
901
902 list_for_each_entry(device, head, dev_list) {
903 if (device->bdev)
904 continue;
905 if (!device->name)
906 continue;
907
908 /* Just open everything we can; ignore failures here */
909 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
910 &bdev, &bh))
911 continue;
912
913 disk_super = (struct btrfs_super_block *)bh->b_data;
914 devid = btrfs_stack_device_id(&disk_super->dev_item);
915 if (devid != device->devid)
916 goto error_brelse;
917
918 if (memcmp(device->uuid, disk_super->dev_item.uuid,
919 BTRFS_UUID_SIZE))
920 goto error_brelse;
921
922 device->generation = btrfs_super_generation(disk_super);
923 if (!latest_dev ||
924 device->generation > latest_dev->generation)
925 latest_dev = device;
926
927 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
928 device->writeable = 0;
929 } else {
930 device->writeable = !bdev_read_only(bdev);
931 seeding = 0;
932 }
933
934 q = bdev_get_queue(bdev);
935 if (blk_queue_discard(q))
936 device->can_discard = 1;
937
938 device->bdev = bdev;
939 device->in_fs_metadata = 0;
940 device->mode = flags;
941
942 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
943 fs_devices->rotating = 1;
944
945 fs_devices->open_devices++;
946 if (device->writeable &&
947 device->devid != BTRFS_DEV_REPLACE_DEVID) {
948 fs_devices->rw_devices++;
949 list_add(&device->dev_alloc_list,
950 &fs_devices->alloc_list);
951 }
952 brelse(bh);
953 continue;
954
955 error_brelse:
956 brelse(bh);
957 blkdev_put(bdev, flags);
958 continue;
959 }
960 if (fs_devices->open_devices == 0) {
961 ret = -EINVAL;
962 goto out;
963 }
964 fs_devices->seeding = seeding;
965 fs_devices->opened = 1;
966 fs_devices->latest_bdev = latest_dev->bdev;
967 fs_devices->total_rw_bytes = 0;
968 out:
969 return ret;
970 }
971
972 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
973 fmode_t flags, void *holder)
974 {
975 int ret;
976
977 mutex_lock(&uuid_mutex);
978 if (fs_devices->opened) {
979 fs_devices->opened++;
980 ret = 0;
981 } else {
982 ret = __btrfs_open_devices(fs_devices, flags, holder);
983 }
984 mutex_unlock(&uuid_mutex);
985 return ret;
986 }
987
988 /*
989 * Look for a btrfs signature on a device. This may be called out of the mount path
990 * and we are not allowed to call set_blocksize during the scan. The superblock
991 * is read via pagecache
992 */
993 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
994 struct btrfs_fs_devices **fs_devices_ret)
995 {
996 struct btrfs_super_block *disk_super;
997 struct block_device *bdev;
998 struct page *page;
999 void *p;
1000 int ret = -EINVAL;
1001 u64 devid;
1002 u64 transid;
1003 u64 total_devices;
1004 u64 bytenr;
1005 pgoff_t index;
1006
1007 /*
1008 * we would like to check all the supers, but that would make
1009 * a btrfs mount succeed after a mkfs from a different FS.
1010 * So, we need to add a special mount option to scan for
1011 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
1012 */
1013 bytenr = btrfs_sb_offset(0);
1014 flags |= FMODE_EXCL;
1015 mutex_lock(&uuid_mutex);
1016
1017 bdev = blkdev_get_by_path(path, flags, holder);
1018
1019 if (IS_ERR(bdev)) {
1020 ret = PTR_ERR(bdev);
1021 goto error;
1022 }
1023
1024 /* make sure our super fits in the device */
1025 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode))
1026 goto error_bdev_put;
1027
1028 /* make sure our super fits in the page */
1029 if (sizeof(*disk_super) > PAGE_CACHE_SIZE)
1030 goto error_bdev_put;
1031
1032 /* make sure our super doesn't straddle pages on disk */
1033 index = bytenr >> PAGE_CACHE_SHIFT;
1034 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index)
1035 goto error_bdev_put;
1036
1037 /* pull in the page with our super */
1038 page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
1039 index, GFP_NOFS);
1040
1041 if (IS_ERR_OR_NULL(page))
1042 goto error_bdev_put;
1043
1044 p = kmap(page);
1045
1046 /* align our pointer to the offset of the super block */
1047 disk_super = p + (bytenr & ~PAGE_CACHE_MASK);
1048
1049 if (btrfs_super_bytenr(disk_super) != bytenr ||
1050 btrfs_super_magic(disk_super) != BTRFS_MAGIC)
1051 goto error_unmap;
1052
1053 devid = btrfs_stack_device_id(&disk_super->dev_item);
1054 transid = btrfs_super_generation(disk_super);
1055 total_devices = btrfs_super_num_devices(disk_super);
1056
1057 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
1058 if (ret > 0) {
1059 if (disk_super->label[0]) {
1060 if (disk_super->label[BTRFS_LABEL_SIZE - 1])
1061 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
1062 printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
1063 } else {
1064 printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
1065 }
1066
1067 printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
1068 ret = 0;
1069 }
1070 if (!ret && fs_devices_ret)
1071 (*fs_devices_ret)->total_devices = total_devices;
1072
1073 error_unmap:
1074 kunmap(page);
1075 page_cache_release(page);
1076
1077 error_bdev_put:
1078 blkdev_put(bdev, flags);
1079 error:
1080 mutex_unlock(&uuid_mutex);
1081 return ret;
1082 }
1083
1084 /* helper to account the used device space in the range */
1085 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
1086 u64 end, u64 *length)
1087 {
1088 struct btrfs_key key;
1089 struct btrfs_root *root = device->dev_root;
1090 struct btrfs_dev_extent *dev_extent;
1091 struct btrfs_path *path;
1092 u64 extent_end;
1093 int ret;
1094 int slot;
1095 struct extent_buffer *l;
1096
1097 *length = 0;
1098
1099 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
1100 return 0;
1101
1102 path = btrfs_alloc_path();
1103 if (!path)
1104 return -ENOMEM;
1105 path->reada = 2;
1106
1107 key.objectid = device->devid;
1108 key.offset = start;
1109 key.type = BTRFS_DEV_EXTENT_KEY;
1110
1111 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1112 if (ret < 0)
1113 goto out;
1114 if (ret > 0) {
1115 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1116 if (ret < 0)
1117 goto out;
1118 }
1119
1120 while (1) {
1121 l = path->nodes[0];
1122 slot = path->slots[0];
1123 if (slot >= btrfs_header_nritems(l)) {
1124 ret = btrfs_next_leaf(root, path);
1125 if (ret == 0)
1126 continue;
1127 if (ret < 0)
1128 goto out;
1129
1130 break;
1131 }
1132 btrfs_item_key_to_cpu(l, &key, slot);
1133
1134 if (key.objectid < device->devid)
1135 goto next;
1136
1137 if (key.objectid > device->devid)
1138 break;
1139
1140 if (key.type != BTRFS_DEV_EXTENT_KEY)
1141 goto next;
1142
1143 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1144 extent_end = key.offset + btrfs_dev_extent_length(l,
1145 dev_extent);
1146 if (key.offset <= start && extent_end > end) {
1147 *length = end - start + 1;
1148 break;
1149 } else if (key.offset <= start && extent_end > start)
1150 *length += extent_end - start;
1151 else if (key.offset > start && extent_end <= end)
1152 *length += extent_end - key.offset;
1153 else if (key.offset > start && key.offset <= end) {
1154 *length += end - key.offset + 1;
1155 break;
1156 } else if (key.offset > end)
1157 break;
1158
1159 next:
1160 path->slots[0]++;
1161 }
1162 ret = 0;
1163 out:
1164 btrfs_free_path(path);
1165 return ret;
1166 }
1167
1168 static int contains_pending_extent(struct btrfs_transaction *transaction,
1169 struct btrfs_device *device,
1170 u64 *start, u64 len)
1171 {
1172 struct btrfs_fs_info *fs_info = device->dev_root->fs_info;
1173 struct extent_map *em;
1174 struct list_head *search_list = &fs_info->pinned_chunks;
1175 int ret = 0;
1176 u64 physical_start = *start;
1177
1178 if (transaction)
1179 search_list = &transaction->pending_chunks;
1180 again:
1181 list_for_each_entry(em, search_list, list) {
1182 struct map_lookup *map;
1183 int i;
1184
1185 map = (struct map_lookup *)em->bdev;
1186 for (i = 0; i < map->num_stripes; i++) {
1187 u64 end;
1188
1189 if (map->stripes[i].dev != device)
1190 continue;
1191 if (map->stripes[i].physical >= physical_start + len ||
1192 map->stripes[i].physical + em->orig_block_len <=
1193 physical_start)
1194 continue;
1195 /*
1196 * Make sure that while processing the pinned list we do
1197 * not override our *start with a lower value, because
1198 * we can have pinned chunks that fall within this
1199 * device hole and that have lower physical addresses
1200 * than the pending chunks we processed before. If we
1201 * do not take this special care we can end up getting
1202 * 2 pending chunks that start at the same physical
1203 * device offsets because the end offset of a pinned
1204 * chunk can be equal to the start offset of some
1205 * pending chunk.
1206 */
1207 end = map->stripes[i].physical + em->orig_block_len;
1208 if (end > *start) {
1209 *start = end;
1210 ret = 1;
1211 }
1212 }
1213 }
1214 if (search_list != &fs_info->pinned_chunks) {
1215 search_list = &fs_info->pinned_chunks;
1216 goto again;
1217 }
1218
1219 return ret;
1220 }
1221
1222
1223 /*
1224 * find_free_dev_extent_start - find free space in the specified device
1225 * @device: the device which we search the free space in
1226 * @num_bytes: the size of the free space that we need
1227 * @search_start: the position from which to begin the search
1228 * @start: store the start of the free space.
1229 * @len: the size of the free space. that we find, or the size
1230 * of the max free space if we don't find suitable free space
1231 *
1232 * this uses a pretty simple search, the expectation is that it is
1233 * called very infrequently and that a given device has a small number
1234 * of extents
1235 *
1236 * @start is used to store the start of the free space if we find. But if we
1237 * don't find suitable free space, it will be used to store the start position
1238 * of the max free space.
1239 *
1240 * @len is used to store the size of the free space that we find.
1241 * But if we don't find suitable free space, it is used to store the size of
1242 * the max free space.
1243 */
1244 int find_free_dev_extent_start(struct btrfs_transaction *transaction,
1245 struct btrfs_device *device, u64 num_bytes,
1246 u64 search_start, u64 *start, u64 *len)
1247 {
1248 struct btrfs_key key;
1249 struct btrfs_root *root = device->dev_root;
1250 struct btrfs_dev_extent *dev_extent;
1251 struct btrfs_path *path;
1252 u64 hole_size;
1253 u64 max_hole_start;
1254 u64 max_hole_size;
1255 u64 extent_end;
1256 u64 search_end = device->total_bytes;
1257 int ret;
1258 int slot;
1259 struct extent_buffer *l;
1260
1261 path = btrfs_alloc_path();
1262 if (!path)
1263 return -ENOMEM;
1264
1265 max_hole_start = search_start;
1266 max_hole_size = 0;
1267
1268 again:
1269 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
1270 ret = -ENOSPC;
1271 goto out;
1272 }
1273
1274 path->reada = 2;
1275 path->search_commit_root = 1;
1276 path->skip_locking = 1;
1277
1278 key.objectid = device->devid;
1279 key.offset = search_start;
1280 key.type = BTRFS_DEV_EXTENT_KEY;
1281
1282 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1283 if (ret < 0)
1284 goto out;
1285 if (ret > 0) {
1286 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1287 if (ret < 0)
1288 goto out;
1289 }
1290
1291 while (1) {
1292 l = path->nodes[0];
1293 slot = path->slots[0];
1294 if (slot >= btrfs_header_nritems(l)) {
1295 ret = btrfs_next_leaf(root, path);
1296 if (ret == 0)
1297 continue;
1298 if (ret < 0)
1299 goto out;
1300
1301 break;
1302 }
1303 btrfs_item_key_to_cpu(l, &key, slot);
1304
1305 if (key.objectid < device->devid)
1306 goto next;
1307
1308 if (key.objectid > device->devid)
1309 break;
1310
1311 if (key.type != BTRFS_DEV_EXTENT_KEY)
1312 goto next;
1313
1314 if (key.offset > search_start) {
1315 hole_size = key.offset - search_start;
1316
1317 /*
1318 * Have to check before we set max_hole_start, otherwise
1319 * we could end up sending back this offset anyway.
1320 */
1321 if (contains_pending_extent(transaction, device,
1322 &search_start,
1323 hole_size)) {
1324 if (key.offset >= search_start) {
1325 hole_size = key.offset - search_start;
1326 } else {
1327 WARN_ON_ONCE(1);
1328 hole_size = 0;
1329 }
1330 }
1331
1332 if (hole_size > max_hole_size) {
1333 max_hole_start = search_start;
1334 max_hole_size = hole_size;
1335 }
1336
1337 /*
1338 * If this free space is greater than which we need,
1339 * it must be the max free space that we have found
1340 * until now, so max_hole_start must point to the start
1341 * of this free space and the length of this free space
1342 * is stored in max_hole_size. Thus, we return
1343 * max_hole_start and max_hole_size and go back to the
1344 * caller.
1345 */
1346 if (hole_size >= num_bytes) {
1347 ret = 0;
1348 goto out;
1349 }
1350 }
1351
1352 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1353 extent_end = key.offset + btrfs_dev_extent_length(l,
1354 dev_extent);
1355 if (extent_end > search_start)
1356 search_start = extent_end;
1357 next:
1358 path->slots[0]++;
1359 cond_resched();
1360 }
1361
1362 /*
1363 * At this point, search_start should be the end of
1364 * allocated dev extents, and when shrinking the device,
1365 * search_end may be smaller than search_start.
1366 */
1367 if (search_end > search_start) {
1368 hole_size = search_end - search_start;
1369
1370 if (contains_pending_extent(transaction, device, &search_start,
1371 hole_size)) {
1372 btrfs_release_path(path);
1373 goto again;
1374 }
1375
1376 if (hole_size > max_hole_size) {
1377 max_hole_start = search_start;
1378 max_hole_size = hole_size;
1379 }
1380 }
1381
1382 /* See above. */
1383 if (max_hole_size < num_bytes)
1384 ret = -ENOSPC;
1385 else
1386 ret = 0;
1387
1388 out:
1389 btrfs_free_path(path);
1390 *start = max_hole_start;
1391 if (len)
1392 *len = max_hole_size;
1393 return ret;
1394 }
1395
1396 int find_free_dev_extent(struct btrfs_trans_handle *trans,
1397 struct btrfs_device *device, u64 num_bytes,
1398 u64 *start, u64 *len)
1399 {
1400 struct btrfs_root *root = device->dev_root;
1401 u64 search_start;
1402
1403 /* FIXME use last free of some kind */
1404
1405 /*
1406 * we don't want to overwrite the superblock on the drive,
1407 * so we make sure to start at an offset of at least 1MB
1408 */
1409 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
1410 return find_free_dev_extent_start(trans->transaction, device,
1411 num_bytes, search_start, start, len);
1412 }
1413
1414 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1415 struct btrfs_device *device,
1416 u64 start, u64 *dev_extent_len)
1417 {
1418 int ret;
1419 struct btrfs_path *path;
1420 struct btrfs_root *root = device->dev_root;
1421 struct btrfs_key key;
1422 struct btrfs_key found_key;
1423 struct extent_buffer *leaf = NULL;
1424 struct btrfs_dev_extent *extent = NULL;
1425
1426 path = btrfs_alloc_path();
1427 if (!path)
1428 return -ENOMEM;
1429
1430 key.objectid = device->devid;
1431 key.offset = start;
1432 key.type = BTRFS_DEV_EXTENT_KEY;
1433 again:
1434 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1435 if (ret > 0) {
1436 ret = btrfs_previous_item(root, path, key.objectid,
1437 BTRFS_DEV_EXTENT_KEY);
1438 if (ret)
1439 goto out;
1440 leaf = path->nodes[0];
1441 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1442 extent = btrfs_item_ptr(leaf, path->slots[0],
1443 struct btrfs_dev_extent);
1444 BUG_ON(found_key.offset > start || found_key.offset +
1445 btrfs_dev_extent_length(leaf, extent) < start);
1446 key = found_key;
1447 btrfs_release_path(path);
1448 goto again;
1449 } else if (ret == 0) {
1450 leaf = path->nodes[0];
1451 extent = btrfs_item_ptr(leaf, path->slots[0],
1452 struct btrfs_dev_extent);
1453 } else {
1454 btrfs_std_error(root->fs_info, ret, "Slot search failed");
1455 goto out;
1456 }
1457
1458 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1459
1460 ret = btrfs_del_item(trans, root, path);
1461 if (ret) {
1462 btrfs_std_error(root->fs_info, ret,
1463 "Failed to remove dev extent item");
1464 } else {
1465 set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
1466 }
1467 out:
1468 btrfs_free_path(path);
1469 return ret;
1470 }
1471
1472 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1473 struct btrfs_device *device,
1474 u64 chunk_tree, u64 chunk_objectid,
1475 u64 chunk_offset, u64 start, u64 num_bytes)
1476 {
1477 int ret;
1478 struct btrfs_path *path;
1479 struct btrfs_root *root = device->dev_root;
1480 struct btrfs_dev_extent *extent;
1481 struct extent_buffer *leaf;
1482 struct btrfs_key key;
1483
1484 WARN_ON(!device->in_fs_metadata);
1485 WARN_ON(device->is_tgtdev_for_dev_replace);
1486 path = btrfs_alloc_path();
1487 if (!path)
1488 return -ENOMEM;
1489
1490 key.objectid = device->devid;
1491 key.offset = start;
1492 key.type = BTRFS_DEV_EXTENT_KEY;
1493 ret = btrfs_insert_empty_item(trans, root, path, &key,
1494 sizeof(*extent));
1495 if (ret)
1496 goto out;
1497
1498 leaf = path->nodes[0];
1499 extent = btrfs_item_ptr(leaf, path->slots[0],
1500 struct btrfs_dev_extent);
1501 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1502 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1503 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1504
1505 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1506 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE);
1507
1508 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1509 btrfs_mark_buffer_dirty(leaf);
1510 out:
1511 btrfs_free_path(path);
1512 return ret;
1513 }
1514
1515 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1516 {
1517 struct extent_map_tree *em_tree;
1518 struct extent_map *em;
1519 struct rb_node *n;
1520 u64 ret = 0;
1521
1522 em_tree = &fs_info->mapping_tree.map_tree;
1523 read_lock(&em_tree->lock);
1524 n = rb_last(&em_tree->map);
1525 if (n) {
1526 em = rb_entry(n, struct extent_map, rb_node);
1527 ret = em->start + em->len;
1528 }
1529 read_unlock(&em_tree->lock);
1530
1531 return ret;
1532 }
1533
1534 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1535 u64 *devid_ret)
1536 {
1537 int ret;
1538 struct btrfs_key key;
1539 struct btrfs_key found_key;
1540 struct btrfs_path *path;
1541
1542 path = btrfs_alloc_path();
1543 if (!path)
1544 return -ENOMEM;
1545
1546 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1547 key.type = BTRFS_DEV_ITEM_KEY;
1548 key.offset = (u64)-1;
1549
1550 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1551 if (ret < 0)
1552 goto error;
1553
1554 BUG_ON(ret == 0); /* Corruption */
1555
1556 ret = btrfs_previous_item(fs_info->chunk_root, path,
1557 BTRFS_DEV_ITEMS_OBJECTID,
1558 BTRFS_DEV_ITEM_KEY);
1559 if (ret) {
1560 *devid_ret = 1;
1561 } else {
1562 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1563 path->slots[0]);
1564 *devid_ret = found_key.offset + 1;
1565 }
1566 ret = 0;
1567 error:
1568 btrfs_free_path(path);
1569 return ret;
1570 }
1571
1572 /*
1573 * the device information is stored in the chunk root
1574 * the btrfs_device struct should be fully filled in
1575 */
1576 static int btrfs_add_device(struct btrfs_trans_handle *trans,
1577 struct btrfs_root *root,
1578 struct btrfs_device *device)
1579 {
1580 int ret;
1581 struct btrfs_path *path;
1582 struct btrfs_dev_item *dev_item;
1583 struct extent_buffer *leaf;
1584 struct btrfs_key key;
1585 unsigned long ptr;
1586
1587 root = root->fs_info->chunk_root;
1588
1589 path = btrfs_alloc_path();
1590 if (!path)
1591 return -ENOMEM;
1592
1593 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1594 key.type = BTRFS_DEV_ITEM_KEY;
1595 key.offset = device->devid;
1596
1597 ret = btrfs_insert_empty_item(trans, root, path, &key,
1598 sizeof(*dev_item));
1599 if (ret)
1600 goto out;
1601
1602 leaf = path->nodes[0];
1603 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1604
1605 btrfs_set_device_id(leaf, dev_item, device->devid);
1606 btrfs_set_device_generation(leaf, dev_item, 0);
1607 btrfs_set_device_type(leaf, dev_item, device->type);
1608 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1609 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1610 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1611 btrfs_set_device_total_bytes(leaf, dev_item,
1612 btrfs_device_get_disk_total_bytes(device));
1613 btrfs_set_device_bytes_used(leaf, dev_item,
1614 btrfs_device_get_bytes_used(device));
1615 btrfs_set_device_group(leaf, dev_item, 0);
1616 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1617 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1618 btrfs_set_device_start_offset(leaf, dev_item, 0);
1619
1620 ptr = btrfs_device_uuid(dev_item);
1621 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1622 ptr = btrfs_device_fsid(dev_item);
1623 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1624 btrfs_mark_buffer_dirty(leaf);
1625
1626 ret = 0;
1627 out:
1628 btrfs_free_path(path);
1629 return ret;
1630 }
1631
1632 /*
1633 * Function to update ctime/mtime for a given device path.
1634 * Mainly used for ctime/mtime based probe like libblkid.
1635 */
1636 static void update_dev_time(char *path_name)
1637 {
1638 struct file *filp;
1639
1640 filp = filp_open(path_name, O_RDWR, 0);
1641 if (IS_ERR(filp))
1642 return;
1643 file_update_time(filp);
1644 filp_close(filp, NULL);
1645 return;
1646 }
1647
1648 static int btrfs_rm_dev_item(struct btrfs_root *root,
1649 struct btrfs_device *device)
1650 {
1651 int ret;
1652 struct btrfs_path *path;
1653 struct btrfs_key key;
1654 struct btrfs_trans_handle *trans;
1655
1656 root = root->fs_info->chunk_root;
1657
1658 path = btrfs_alloc_path();
1659 if (!path)
1660 return -ENOMEM;
1661
1662 trans = btrfs_start_transaction(root, 0);
1663 if (IS_ERR(trans)) {
1664 btrfs_free_path(path);
1665 return PTR_ERR(trans);
1666 }
1667 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1668 key.type = BTRFS_DEV_ITEM_KEY;
1669 key.offset = device->devid;
1670
1671 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1672 if (ret < 0)
1673 goto out;
1674
1675 if (ret > 0) {
1676 ret = -ENOENT;
1677 goto out;
1678 }
1679
1680 ret = btrfs_del_item(trans, root, path);
1681 if (ret)
1682 goto out;
1683 out:
1684 btrfs_free_path(path);
1685 btrfs_commit_transaction(trans, root);
1686 return ret;
1687 }
1688
1689 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1690 {
1691 struct btrfs_device *device;
1692 struct btrfs_device *next_device;
1693 struct block_device *bdev;
1694 struct buffer_head *bh = NULL;
1695 struct btrfs_super_block *disk_super;
1696 struct btrfs_fs_devices *cur_devices;
1697 u64 all_avail;
1698 u64 devid;
1699 u64 num_devices;
1700 u8 *dev_uuid;
1701 unsigned seq;
1702 int ret = 0;
1703 bool clear_super = false;
1704
1705 mutex_lock(&uuid_mutex);
1706
1707 do {
1708 seq = read_seqbegin(&root->fs_info->profiles_lock);
1709
1710 all_avail = root->fs_info->avail_data_alloc_bits |
1711 root->fs_info->avail_system_alloc_bits |
1712 root->fs_info->avail_metadata_alloc_bits;
1713 } while (read_seqretry(&root->fs_info->profiles_lock, seq));
1714
1715 num_devices = root->fs_info->fs_devices->num_devices;
1716 btrfs_dev_replace_lock(&root->fs_info->dev_replace);
1717 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1718 WARN_ON(num_devices < 1);
1719 num_devices--;
1720 }
1721 btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
1722
1723 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
1724 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
1725 goto out;
1726 }
1727
1728 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
1729 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
1730 goto out;
1731 }
1732
1733 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
1734 root->fs_info->fs_devices->rw_devices <= 2) {
1735 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
1736 goto out;
1737 }
1738 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
1739 root->fs_info->fs_devices->rw_devices <= 3) {
1740 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
1741 goto out;
1742 }
1743
1744 if (strcmp(device_path, "missing") == 0) {
1745 struct list_head *devices;
1746 struct btrfs_device *tmp;
1747
1748 device = NULL;
1749 devices = &root->fs_info->fs_devices->devices;
1750 /*
1751 * It is safe to read the devices since the volume_mutex
1752 * is held.
1753 */
1754 list_for_each_entry(tmp, devices, dev_list) {
1755 if (tmp->in_fs_metadata &&
1756 !tmp->is_tgtdev_for_dev_replace &&
1757 !tmp->bdev) {
1758 device = tmp;
1759 break;
1760 }
1761 }
1762 bdev = NULL;
1763 bh = NULL;
1764 disk_super = NULL;
1765 if (!device) {
1766 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
1767 goto out;
1768 }
1769 } else {
1770 ret = btrfs_get_bdev_and_sb(device_path,
1771 FMODE_WRITE | FMODE_EXCL,
1772 root->fs_info->bdev_holder, 0,
1773 &bdev, &bh);
1774 if (ret)
1775 goto out;
1776 disk_super = (struct btrfs_super_block *)bh->b_data;
1777 devid = btrfs_stack_device_id(&disk_super->dev_item);
1778 dev_uuid = disk_super->dev_item.uuid;
1779 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1780 disk_super->fsid);
1781 if (!device) {
1782 ret = -ENOENT;
1783 goto error_brelse;
1784 }
1785 }
1786
1787 if (device->is_tgtdev_for_dev_replace) {
1788 ret = BTRFS_ERROR_DEV_TGT_REPLACE;
1789 goto error_brelse;
1790 }
1791
1792 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1793 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
1794 goto error_brelse;
1795 }
1796
1797 if (device->writeable) {
1798 lock_chunks(root);
1799 list_del_init(&device->dev_alloc_list);
1800 device->fs_devices->rw_devices--;
1801 unlock_chunks(root);
1802 clear_super = true;
1803 }
1804
1805 mutex_unlock(&uuid_mutex);
1806 ret = btrfs_shrink_device(device, 0);
1807 mutex_lock(&uuid_mutex);
1808 if (ret)
1809 goto error_undo;
1810
1811 /*
1812 * TODO: the superblock still includes this device in its num_devices
1813 * counter although write_all_supers() is not locked out. This
1814 * could give a filesystem state which requires a degraded mount.
1815 */
1816 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1817 if (ret)
1818 goto error_undo;
1819
1820 device->in_fs_metadata = 0;
1821 btrfs_scrub_cancel_dev(root->fs_info, device);
1822
1823 /*
1824 * the device list mutex makes sure that we don't change
1825 * the device list while someone else is writing out all
1826 * the device supers. Whoever is writing all supers, should
1827 * lock the device list mutex before getting the number of
1828 * devices in the super block (super_copy). Conversely,
1829 * whoever updates the number of devices in the super block
1830 * (super_copy) should hold the device list mutex.
1831 */
1832
1833 cur_devices = device->fs_devices;
1834 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1835 list_del_rcu(&device->dev_list);
1836
1837 device->fs_devices->num_devices--;
1838 device->fs_devices->total_devices--;
1839
1840 if (device->missing)
1841 device->fs_devices->missing_devices--;
1842
1843 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1844 struct btrfs_device, dev_list);
1845 if (device->bdev == root->fs_info->sb->s_bdev)
1846 root->fs_info->sb->s_bdev = next_device->bdev;
1847 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1848 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1849
1850 if (device->bdev) {
1851 device->fs_devices->open_devices--;
1852 /* remove sysfs entry */
1853 btrfs_sysfs_rm_device_link(root->fs_info->fs_devices, device);
1854 }
1855
1856 call_rcu(&device->rcu, free_device);
1857
1858 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1859 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1860 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1861
1862 if (cur_devices->open_devices == 0) {
1863 struct btrfs_fs_devices *fs_devices;
1864 fs_devices = root->fs_info->fs_devices;
1865 while (fs_devices) {
1866 if (fs_devices->seed == cur_devices) {
1867 fs_devices->seed = cur_devices->seed;
1868 break;
1869 }
1870 fs_devices = fs_devices->seed;
1871 }
1872 cur_devices->seed = NULL;
1873 __btrfs_close_devices(cur_devices);
1874 free_fs_devices(cur_devices);
1875 }
1876
1877 root->fs_info->num_tolerated_disk_barrier_failures =
1878 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1879
1880 /*
1881 * at this point, the device is zero sized. We want to
1882 * remove it from the devices list and zero out the old super
1883 */
1884 if (clear_super && disk_super) {
1885 u64 bytenr;
1886 int i;
1887
1888 /* make sure this device isn't detected as part of
1889 * the FS anymore
1890 */
1891 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1892 set_buffer_dirty(bh);
1893 sync_dirty_buffer(bh);
1894
1895 /* clear the mirror copies of super block on the disk
1896 * being removed, 0th copy is been taken care above and
1897 * the below would take of the rest
1898 */
1899 for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1900 bytenr = btrfs_sb_offset(i);
1901 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
1902 i_size_read(bdev->bd_inode))
1903 break;
1904
1905 brelse(bh);
1906 bh = __bread(bdev, bytenr / 4096,
1907 BTRFS_SUPER_INFO_SIZE);
1908 if (!bh)
1909 continue;
1910
1911 disk_super = (struct btrfs_super_block *)bh->b_data;
1912
1913 if (btrfs_super_bytenr(disk_super) != bytenr ||
1914 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1915 continue;
1916 }
1917 memset(&disk_super->magic, 0,
1918 sizeof(disk_super->magic));
1919 set_buffer_dirty(bh);
1920 sync_dirty_buffer(bh);
1921 }
1922 }
1923
1924 ret = 0;
1925
1926 if (bdev) {
1927 /* Notify udev that device has changed */
1928 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
1929
1930 /* Update ctime/mtime for device path for libblkid */
1931 update_dev_time(device_path);
1932 }
1933
1934 error_brelse:
1935 brelse(bh);
1936 if (bdev)
1937 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1938 out:
1939 mutex_unlock(&uuid_mutex);
1940 return ret;
1941 error_undo:
1942 if (device->writeable) {
1943 lock_chunks(root);
1944 list_add(&device->dev_alloc_list,
1945 &root->fs_info->fs_devices->alloc_list);
1946 device->fs_devices->rw_devices++;
1947 unlock_chunks(root);
1948 }
1949 goto error_brelse;
1950 }
1951
1952 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
1953 struct btrfs_device *srcdev)
1954 {
1955 struct btrfs_fs_devices *fs_devices;
1956
1957 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1958
1959 /*
1960 * in case of fs with no seed, srcdev->fs_devices will point
1961 * to fs_devices of fs_info. However when the dev being replaced is
1962 * a seed dev it will point to the seed's local fs_devices. In short
1963 * srcdev will have its correct fs_devices in both the cases.
1964 */
1965 fs_devices = srcdev->fs_devices;
1966
1967 list_del_rcu(&srcdev->dev_list);
1968 list_del_rcu(&srcdev->dev_alloc_list);
1969 fs_devices->num_devices--;
1970 if (srcdev->missing)
1971 fs_devices->missing_devices--;
1972
1973 if (srcdev->writeable) {
1974 fs_devices->rw_devices--;
1975 /* zero out the old super if it is writable */
1976 btrfs_scratch_superblocks(srcdev->bdev, srcdev->name->str);
1977 }
1978
1979 if (srcdev->bdev)
1980 fs_devices->open_devices--;
1981 }
1982
1983 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
1984 struct btrfs_device *srcdev)
1985 {
1986 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
1987
1988 call_rcu(&srcdev->rcu, free_device);
1989
1990 /*
1991 * unless fs_devices is seed fs, num_devices shouldn't go
1992 * zero
1993 */
1994 BUG_ON(!fs_devices->num_devices && !fs_devices->seeding);
1995
1996 /* if this is no devs we rather delete the fs_devices */
1997 if (!fs_devices->num_devices) {
1998 struct btrfs_fs_devices *tmp_fs_devices;
1999
2000 tmp_fs_devices = fs_info->fs_devices;
2001 while (tmp_fs_devices) {
2002 if (tmp_fs_devices->seed == fs_devices) {
2003 tmp_fs_devices->seed = fs_devices->seed;
2004 break;
2005 }
2006 tmp_fs_devices = tmp_fs_devices->seed;
2007 }
2008 fs_devices->seed = NULL;
2009 __btrfs_close_devices(fs_devices);
2010 free_fs_devices(fs_devices);
2011 }
2012 }
2013
2014 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
2015 struct btrfs_device *tgtdev)
2016 {
2017 struct btrfs_device *next_device;
2018
2019 mutex_lock(&uuid_mutex);
2020 WARN_ON(!tgtdev);
2021 mutex_lock(&fs_info->fs_devices->device_list_mutex);
2022
2023 btrfs_sysfs_rm_device_link(fs_info->fs_devices, tgtdev);
2024
2025 if (tgtdev->bdev) {
2026 btrfs_scratch_superblocks(tgtdev->bdev, tgtdev->name->str);
2027 fs_info->fs_devices->open_devices--;
2028 }
2029 fs_info->fs_devices->num_devices--;
2030
2031 next_device = list_entry(fs_info->fs_devices->devices.next,
2032 struct btrfs_device, dev_list);
2033 if (tgtdev->bdev == fs_info->sb->s_bdev)
2034 fs_info->sb->s_bdev = next_device->bdev;
2035 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
2036 fs_info->fs_devices->latest_bdev = next_device->bdev;
2037 list_del_rcu(&tgtdev->dev_list);
2038
2039 call_rcu(&tgtdev->rcu, free_device);
2040
2041 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2042 mutex_unlock(&uuid_mutex);
2043 }
2044
2045 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
2046 struct btrfs_device **device)
2047 {
2048 int ret = 0;
2049 struct btrfs_super_block *disk_super;
2050 u64 devid;
2051 u8 *dev_uuid;
2052 struct block_device *bdev;
2053 struct buffer_head *bh;
2054
2055 *device = NULL;
2056 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ,
2057 root->fs_info->bdev_holder, 0, &bdev, &bh);
2058 if (ret)
2059 return ret;
2060 disk_super = (struct btrfs_super_block *)bh->b_data;
2061 devid = btrfs_stack_device_id(&disk_super->dev_item);
2062 dev_uuid = disk_super->dev_item.uuid;
2063 *device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2064 disk_super->fsid);
2065 brelse(bh);
2066 if (!*device)
2067 ret = -ENOENT;
2068 blkdev_put(bdev, FMODE_READ);
2069 return ret;
2070 }
2071
2072 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
2073 char *device_path,
2074 struct btrfs_device **device)
2075 {
2076 *device = NULL;
2077 if (strcmp(device_path, "missing") == 0) {
2078 struct list_head *devices;
2079 struct btrfs_device *tmp;
2080
2081 devices = &root->fs_info->fs_devices->devices;
2082 /*
2083 * It is safe to read the devices since the volume_mutex
2084 * is held by the caller.
2085 */
2086 list_for_each_entry(tmp, devices, dev_list) {
2087 if (tmp->in_fs_metadata && !tmp->bdev) {
2088 *device = tmp;
2089 break;
2090 }
2091 }
2092
2093 if (!*device)
2094 return BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
2095
2096 return 0;
2097 } else {
2098 return btrfs_find_device_by_path(root, device_path, device);
2099 }
2100 }
2101
2102 /*
2103 * does all the dirty work required for changing file system's UUID.
2104 */
2105 static int btrfs_prepare_sprout(struct btrfs_root *root)
2106 {
2107 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2108 struct btrfs_fs_devices *old_devices;
2109 struct btrfs_fs_devices *seed_devices;
2110 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
2111 struct btrfs_device *device;
2112 u64 super_flags;
2113
2114 BUG_ON(!mutex_is_locked(&uuid_mutex));
2115 if (!fs_devices->seeding)
2116 return -EINVAL;
2117
2118 seed_devices = __alloc_fs_devices();
2119 if (IS_ERR(seed_devices))
2120 return PTR_ERR(seed_devices);
2121
2122 old_devices = clone_fs_devices(fs_devices);
2123 if (IS_ERR(old_devices)) {
2124 kfree(seed_devices);
2125 return PTR_ERR(old_devices);
2126 }
2127
2128 list_add(&old_devices->list, &fs_uuids);
2129
2130 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
2131 seed_devices->opened = 1;
2132 INIT_LIST_HEAD(&seed_devices->devices);
2133 INIT_LIST_HEAD(&seed_devices->alloc_list);
2134 mutex_init(&seed_devices->device_list_mutex);
2135
2136 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2137 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
2138 synchronize_rcu);
2139 list_for_each_entry(device, &seed_devices->devices, dev_list)
2140 device->fs_devices = seed_devices;
2141
2142 lock_chunks(root);
2143 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
2144 unlock_chunks(root);
2145
2146 fs_devices->seeding = 0;
2147 fs_devices->num_devices = 0;
2148 fs_devices->open_devices = 0;
2149 fs_devices->missing_devices = 0;
2150 fs_devices->rotating = 0;
2151 fs_devices->seed = seed_devices;
2152
2153 generate_random_uuid(fs_devices->fsid);
2154 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2155 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2156 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2157
2158 super_flags = btrfs_super_flags(disk_super) &
2159 ~BTRFS_SUPER_FLAG_SEEDING;
2160 btrfs_set_super_flags(disk_super, super_flags);
2161
2162 return 0;
2163 }
2164
2165 /*
2166 * strore the expected generation for seed devices in device items.
2167 */
2168 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
2169 struct btrfs_root *root)
2170 {
2171 struct btrfs_path *path;
2172 struct extent_buffer *leaf;
2173 struct btrfs_dev_item *dev_item;
2174 struct btrfs_device *device;
2175 struct btrfs_key key;
2176 u8 fs_uuid[BTRFS_UUID_SIZE];
2177 u8 dev_uuid[BTRFS_UUID_SIZE];
2178 u64 devid;
2179 int ret;
2180
2181 path = btrfs_alloc_path();
2182 if (!path)
2183 return -ENOMEM;
2184
2185 root = root->fs_info->chunk_root;
2186 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2187 key.offset = 0;
2188 key.type = BTRFS_DEV_ITEM_KEY;
2189
2190 while (1) {
2191 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2192 if (ret < 0)
2193 goto error;
2194
2195 leaf = path->nodes[0];
2196 next_slot:
2197 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2198 ret = btrfs_next_leaf(root, path);
2199 if (ret > 0)
2200 break;
2201 if (ret < 0)
2202 goto error;
2203 leaf = path->nodes[0];
2204 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2205 btrfs_release_path(path);
2206 continue;
2207 }
2208
2209 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2210 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2211 key.type != BTRFS_DEV_ITEM_KEY)
2212 break;
2213
2214 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2215 struct btrfs_dev_item);
2216 devid = btrfs_device_id(leaf, dev_item);
2217 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2218 BTRFS_UUID_SIZE);
2219 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2220 BTRFS_UUID_SIZE);
2221 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2222 fs_uuid);
2223 BUG_ON(!device); /* Logic error */
2224
2225 if (device->fs_devices->seeding) {
2226 btrfs_set_device_generation(leaf, dev_item,
2227 device->generation);
2228 btrfs_mark_buffer_dirty(leaf);
2229 }
2230
2231 path->slots[0]++;
2232 goto next_slot;
2233 }
2234 ret = 0;
2235 error:
2236 btrfs_free_path(path);
2237 return ret;
2238 }
2239
2240 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
2241 {
2242 struct request_queue *q;
2243 struct btrfs_trans_handle *trans;
2244 struct btrfs_device *device;
2245 struct block_device *bdev;
2246 struct list_head *devices;
2247 struct super_block *sb = root->fs_info->sb;
2248 struct rcu_string *name;
2249 u64 tmp;
2250 int seeding_dev = 0;
2251 int ret = 0;
2252
2253 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
2254 return -EROFS;
2255
2256 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2257 root->fs_info->bdev_holder);
2258 if (IS_ERR(bdev))
2259 return PTR_ERR(bdev);
2260
2261 if (root->fs_info->fs_devices->seeding) {
2262 seeding_dev = 1;
2263 down_write(&sb->s_umount);
2264 mutex_lock(&uuid_mutex);
2265 }
2266
2267 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2268
2269 devices = &root->fs_info->fs_devices->devices;
2270
2271 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2272 list_for_each_entry(device, devices, dev_list) {
2273 if (device->bdev == bdev) {
2274 ret = -EEXIST;
2275 mutex_unlock(
2276 &root->fs_info->fs_devices->device_list_mutex);
2277 goto error;
2278 }
2279 }
2280 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2281
2282 device = btrfs_alloc_device(root->fs_info, NULL, NULL);
2283 if (IS_ERR(device)) {
2284 /* we can safely leave the fs_devices entry around */
2285 ret = PTR_ERR(device);
2286 goto error;
2287 }
2288
2289 name = rcu_string_strdup(device_path, GFP_NOFS);
2290 if (!name) {
2291 kfree(device);
2292 ret = -ENOMEM;
2293 goto error;
2294 }
2295 rcu_assign_pointer(device->name, name);
2296
2297 trans = btrfs_start_transaction(root, 0);
2298 if (IS_ERR(trans)) {
2299 rcu_string_free(device->name);
2300 kfree(device);
2301 ret = PTR_ERR(trans);
2302 goto error;
2303 }
2304
2305 q = bdev_get_queue(bdev);
2306 if (blk_queue_discard(q))
2307 device->can_discard = 1;
2308 device->writeable = 1;
2309 device->generation = trans->transid;
2310 device->io_width = root->sectorsize;
2311 device->io_align = root->sectorsize;
2312 device->sector_size = root->sectorsize;
2313 device->total_bytes = i_size_read(bdev->bd_inode);
2314 device->disk_total_bytes = device->total_bytes;
2315 device->commit_total_bytes = device->total_bytes;
2316 device->dev_root = root->fs_info->dev_root;
2317 device->bdev = bdev;
2318 device->in_fs_metadata = 1;
2319 device->is_tgtdev_for_dev_replace = 0;
2320 device->mode = FMODE_EXCL;
2321 device->dev_stats_valid = 1;
2322 set_blocksize(device->bdev, 4096);
2323
2324 if (seeding_dev) {
2325 sb->s_flags &= ~MS_RDONLY;
2326 ret = btrfs_prepare_sprout(root);
2327 BUG_ON(ret); /* -ENOMEM */
2328 }
2329
2330 device->fs_devices = root->fs_info->fs_devices;
2331
2332 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2333 lock_chunks(root);
2334 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
2335 list_add(&device->dev_alloc_list,
2336 &root->fs_info->fs_devices->alloc_list);
2337 root->fs_info->fs_devices->num_devices++;
2338 root->fs_info->fs_devices->open_devices++;
2339 root->fs_info->fs_devices->rw_devices++;
2340 root->fs_info->fs_devices->total_devices++;
2341 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
2342
2343 spin_lock(&root->fs_info->free_chunk_lock);
2344 root->fs_info->free_chunk_space += device->total_bytes;
2345 spin_unlock(&root->fs_info->free_chunk_lock);
2346
2347 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
2348 root->fs_info->fs_devices->rotating = 1;
2349
2350 tmp = btrfs_super_total_bytes(root->fs_info->super_copy);
2351 btrfs_set_super_total_bytes(root->fs_info->super_copy,
2352 tmp + device->total_bytes);
2353
2354 tmp = btrfs_super_num_devices(root->fs_info->super_copy);
2355 btrfs_set_super_num_devices(root->fs_info->super_copy,
2356 tmp + 1);
2357
2358 /* add sysfs device entry */
2359 btrfs_sysfs_add_device_link(root->fs_info->fs_devices, device);
2360
2361 /*
2362 * we've got more storage, clear any full flags on the space
2363 * infos
2364 */
2365 btrfs_clear_space_info_full(root->fs_info);
2366
2367 unlock_chunks(root);
2368 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2369
2370 if (seeding_dev) {
2371 lock_chunks(root);
2372 ret = init_first_rw_device(trans, root, device);
2373 unlock_chunks(root);
2374 if (ret) {
2375 btrfs_abort_transaction(trans, root, ret);
2376 goto error_trans;
2377 }
2378 }
2379
2380 ret = btrfs_add_device(trans, root, device);
2381 if (ret) {
2382 btrfs_abort_transaction(trans, root, ret);
2383 goto error_trans;
2384 }
2385
2386 if (seeding_dev) {
2387 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2388
2389 ret = btrfs_finish_sprout(trans, root);
2390 if (ret) {
2391 btrfs_abort_transaction(trans, root, ret);
2392 goto error_trans;
2393 }
2394
2395 /* Sprouting would change fsid of the mounted root,
2396 * so rename the fsid on the sysfs
2397 */
2398 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU",
2399 root->fs_info->fsid);
2400 if (kobject_rename(&root->fs_info->fs_devices->fsid_kobj,
2401 fsid_buf))
2402 btrfs_warn(root->fs_info,
2403 "sysfs: failed to create fsid for sprout");
2404 }
2405
2406 root->fs_info->num_tolerated_disk_barrier_failures =
2407 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2408 ret = btrfs_commit_transaction(trans, root);
2409
2410 if (seeding_dev) {
2411 mutex_unlock(&uuid_mutex);
2412 up_write(&sb->s_umount);
2413
2414 if (ret) /* transaction commit */
2415 return ret;
2416
2417 ret = btrfs_relocate_sys_chunks(root);
2418 if (ret < 0)
2419 btrfs_std_error(root->fs_info, ret,
2420 "Failed to relocate sys chunks after "
2421 "device initialization. This can be fixed "
2422 "using the \"btrfs balance\" command.");
2423 trans = btrfs_attach_transaction(root);
2424 if (IS_ERR(trans)) {
2425 if (PTR_ERR(trans) == -ENOENT)
2426 return 0;
2427 return PTR_ERR(trans);
2428 }
2429 ret = btrfs_commit_transaction(trans, root);
2430 }
2431
2432 /* Update ctime/mtime for libblkid */
2433 update_dev_time(device_path);
2434 return ret;
2435
2436 error_trans:
2437 btrfs_end_transaction(trans, root);
2438 rcu_string_free(device->name);
2439 btrfs_sysfs_rm_device_link(root->fs_info->fs_devices, device);
2440 kfree(device);
2441 error:
2442 blkdev_put(bdev, FMODE_EXCL);
2443 if (seeding_dev) {
2444 mutex_unlock(&uuid_mutex);
2445 up_write(&sb->s_umount);
2446 }
2447 return ret;
2448 }
2449
2450 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2451 struct btrfs_device *srcdev,
2452 struct btrfs_device **device_out)
2453 {
2454 struct request_queue *q;
2455 struct btrfs_device *device;
2456 struct block_device *bdev;
2457 struct btrfs_fs_info *fs_info = root->fs_info;
2458 struct list_head *devices;
2459 struct rcu_string *name;
2460 u64 devid = BTRFS_DEV_REPLACE_DEVID;
2461 int ret = 0;
2462
2463 *device_out = NULL;
2464 if (fs_info->fs_devices->seeding) {
2465 btrfs_err(fs_info, "the filesystem is a seed filesystem!");
2466 return -EINVAL;
2467 }
2468
2469 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2470 fs_info->bdev_holder);
2471 if (IS_ERR(bdev)) {
2472 btrfs_err(fs_info, "target device %s is invalid!", device_path);
2473 return PTR_ERR(bdev);
2474 }
2475
2476 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2477
2478 devices = &fs_info->fs_devices->devices;
2479 list_for_each_entry(device, devices, dev_list) {
2480 if (device->bdev == bdev) {
2481 btrfs_err(fs_info, "target device is in the filesystem!");
2482 ret = -EEXIST;
2483 goto error;
2484 }
2485 }
2486
2487
2488 if (i_size_read(bdev->bd_inode) <
2489 btrfs_device_get_total_bytes(srcdev)) {
2490 btrfs_err(fs_info, "target device is smaller than source device!");
2491 ret = -EINVAL;
2492 goto error;
2493 }
2494
2495
2496 device = btrfs_alloc_device(NULL, &devid, NULL);
2497 if (IS_ERR(device)) {
2498 ret = PTR_ERR(device);
2499 goto error;
2500 }
2501
2502 name = rcu_string_strdup(device_path, GFP_NOFS);
2503 if (!name) {
2504 kfree(device);
2505 ret = -ENOMEM;
2506 goto error;
2507 }
2508 rcu_assign_pointer(device->name, name);
2509
2510 q = bdev_get_queue(bdev);
2511 if (blk_queue_discard(q))
2512 device->can_discard = 1;
2513 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2514 device->writeable = 1;
2515 device->generation = 0;
2516 device->io_width = root->sectorsize;
2517 device->io_align = root->sectorsize;
2518 device->sector_size = root->sectorsize;
2519 device->total_bytes = btrfs_device_get_total_bytes(srcdev);
2520 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev);
2521 device->bytes_used = btrfs_device_get_bytes_used(srcdev);
2522 ASSERT(list_empty(&srcdev->resized_list));
2523 device->commit_total_bytes = srcdev->commit_total_bytes;
2524 device->commit_bytes_used = device->bytes_used;
2525 device->dev_root = fs_info->dev_root;
2526 device->bdev = bdev;
2527 device->in_fs_metadata = 1;
2528 device->is_tgtdev_for_dev_replace = 1;
2529 device->mode = FMODE_EXCL;
2530 device->dev_stats_valid = 1;
2531 set_blocksize(device->bdev, 4096);
2532 device->fs_devices = fs_info->fs_devices;
2533 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2534 fs_info->fs_devices->num_devices++;
2535 fs_info->fs_devices->open_devices++;
2536 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2537
2538 *device_out = device;
2539 return ret;
2540
2541 error:
2542 blkdev_put(bdev, FMODE_EXCL);
2543 return ret;
2544 }
2545
2546 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2547 struct btrfs_device *tgtdev)
2548 {
2549 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2550 tgtdev->io_width = fs_info->dev_root->sectorsize;
2551 tgtdev->io_align = fs_info->dev_root->sectorsize;
2552 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2553 tgtdev->dev_root = fs_info->dev_root;
2554 tgtdev->in_fs_metadata = 1;
2555 }
2556
2557 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2558 struct btrfs_device *device)
2559 {
2560 int ret;
2561 struct btrfs_path *path;
2562 struct btrfs_root *root;
2563 struct btrfs_dev_item *dev_item;
2564 struct extent_buffer *leaf;
2565 struct btrfs_key key;
2566
2567 root = device->dev_root->fs_info->chunk_root;
2568
2569 path = btrfs_alloc_path();
2570 if (!path)
2571 return -ENOMEM;
2572
2573 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2574 key.type = BTRFS_DEV_ITEM_KEY;
2575 key.offset = device->devid;
2576
2577 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2578 if (ret < 0)
2579 goto out;
2580
2581 if (ret > 0) {
2582 ret = -ENOENT;
2583 goto out;
2584 }
2585
2586 leaf = path->nodes[0];
2587 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2588
2589 btrfs_set_device_id(leaf, dev_item, device->devid);
2590 btrfs_set_device_type(leaf, dev_item, device->type);
2591 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2592 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2593 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2594 btrfs_set_device_total_bytes(leaf, dev_item,
2595 btrfs_device_get_disk_total_bytes(device));
2596 btrfs_set_device_bytes_used(leaf, dev_item,
2597 btrfs_device_get_bytes_used(device));
2598 btrfs_mark_buffer_dirty(leaf);
2599
2600 out:
2601 btrfs_free_path(path);
2602 return ret;
2603 }
2604
2605 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2606 struct btrfs_device *device, u64 new_size)
2607 {
2608 struct btrfs_super_block *super_copy =
2609 device->dev_root->fs_info->super_copy;
2610 struct btrfs_fs_devices *fs_devices;
2611 u64 old_total;
2612 u64 diff;
2613
2614 if (!device->writeable)
2615 return -EACCES;
2616
2617 lock_chunks(device->dev_root);
2618 old_total = btrfs_super_total_bytes(super_copy);
2619 diff = new_size - device->total_bytes;
2620
2621 if (new_size <= device->total_bytes ||
2622 device->is_tgtdev_for_dev_replace) {
2623 unlock_chunks(device->dev_root);
2624 return -EINVAL;
2625 }
2626
2627 fs_devices = device->dev_root->fs_info->fs_devices;
2628
2629 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2630 device->fs_devices->total_rw_bytes += diff;
2631
2632 btrfs_device_set_total_bytes(device, new_size);
2633 btrfs_device_set_disk_total_bytes(device, new_size);
2634 btrfs_clear_space_info_full(device->dev_root->fs_info);
2635 if (list_empty(&device->resized_list))
2636 list_add_tail(&device->resized_list,
2637 &fs_devices->resized_devices);
2638 unlock_chunks(device->dev_root);
2639
2640 return btrfs_update_device(trans, device);
2641 }
2642
2643 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2644 struct btrfs_root *root, u64 chunk_objectid,
2645 u64 chunk_offset)
2646 {
2647 int ret;
2648 struct btrfs_path *path;
2649 struct btrfs_key key;
2650
2651 root = root->fs_info->chunk_root;
2652 path = btrfs_alloc_path();
2653 if (!path)
2654 return -ENOMEM;
2655
2656 key.objectid = chunk_objectid;
2657 key.offset = chunk_offset;
2658 key.type = BTRFS_CHUNK_ITEM_KEY;
2659
2660 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2661 if (ret < 0)
2662 goto out;
2663 else if (ret > 0) { /* Logic error or corruption */
2664 btrfs_std_error(root->fs_info, -ENOENT,
2665 "Failed lookup while freeing chunk.");
2666 ret = -ENOENT;
2667 goto out;
2668 }
2669
2670 ret = btrfs_del_item(trans, root, path);
2671 if (ret < 0)
2672 btrfs_std_error(root->fs_info, ret,
2673 "Failed to delete chunk item.");
2674 out:
2675 btrfs_free_path(path);
2676 return ret;
2677 }
2678
2679 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2680 chunk_offset)
2681 {
2682 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2683 struct btrfs_disk_key *disk_key;
2684 struct btrfs_chunk *chunk;
2685 u8 *ptr;
2686 int ret = 0;
2687 u32 num_stripes;
2688 u32 array_size;
2689 u32 len = 0;
2690 u32 cur;
2691 struct btrfs_key key;
2692
2693 lock_chunks(root);
2694 array_size = btrfs_super_sys_array_size(super_copy);
2695
2696 ptr = super_copy->sys_chunk_array;
2697 cur = 0;
2698
2699 while (cur < array_size) {
2700 disk_key = (struct btrfs_disk_key *)ptr;
2701 btrfs_disk_key_to_cpu(&key, disk_key);
2702
2703 len = sizeof(*disk_key);
2704
2705 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2706 chunk = (struct btrfs_chunk *)(ptr + len);
2707 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2708 len += btrfs_chunk_item_size(num_stripes);
2709 } else {
2710 ret = -EIO;
2711 break;
2712 }
2713 if (key.objectid == chunk_objectid &&
2714 key.offset == chunk_offset) {
2715 memmove(ptr, ptr + len, array_size - (cur + len));
2716 array_size -= len;
2717 btrfs_set_super_sys_array_size(super_copy, array_size);
2718 } else {
2719 ptr += len;
2720 cur += len;
2721 }
2722 }
2723 unlock_chunks(root);
2724 return ret;
2725 }
2726
2727 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
2728 struct btrfs_root *root, u64 chunk_offset)
2729 {
2730 struct extent_map_tree *em_tree;
2731 struct extent_map *em;
2732 struct btrfs_root *extent_root = root->fs_info->extent_root;
2733 struct map_lookup *map;
2734 u64 dev_extent_len = 0;
2735 u64 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2736 int i, ret = 0;
2737
2738 /* Just in case */
2739 root = root->fs_info->chunk_root;
2740 em_tree = &root->fs_info->mapping_tree.map_tree;
2741
2742 read_lock(&em_tree->lock);
2743 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2744 read_unlock(&em_tree->lock);
2745
2746 if (!em || em->start > chunk_offset ||
2747 em->start + em->len < chunk_offset) {
2748 /*
2749 * This is a logic error, but we don't want to just rely on the
2750 * user having built with ASSERT enabled, so if ASSERT doens't
2751 * do anything we still error out.
2752 */
2753 ASSERT(0);
2754 if (em)
2755 free_extent_map(em);
2756 return -EINVAL;
2757 }
2758 map = (struct map_lookup *)em->bdev;
2759 lock_chunks(root->fs_info->chunk_root);
2760 check_system_chunk(trans, extent_root, map->type);
2761 unlock_chunks(root->fs_info->chunk_root);
2762
2763 for (i = 0; i < map->num_stripes; i++) {
2764 struct btrfs_device *device = map->stripes[i].dev;
2765 ret = btrfs_free_dev_extent(trans, device,
2766 map->stripes[i].physical,
2767 &dev_extent_len);
2768 if (ret) {
2769 btrfs_abort_transaction(trans, root, ret);
2770 goto out;
2771 }
2772
2773 if (device->bytes_used > 0) {
2774 lock_chunks(root);
2775 btrfs_device_set_bytes_used(device,
2776 device->bytes_used - dev_extent_len);
2777 spin_lock(&root->fs_info->free_chunk_lock);
2778 root->fs_info->free_chunk_space += dev_extent_len;
2779 spin_unlock(&root->fs_info->free_chunk_lock);
2780 btrfs_clear_space_info_full(root->fs_info);
2781 unlock_chunks(root);
2782 }
2783
2784 if (map->stripes[i].dev) {
2785 ret = btrfs_update_device(trans, map->stripes[i].dev);
2786 if (ret) {
2787 btrfs_abort_transaction(trans, root, ret);
2788 goto out;
2789 }
2790 }
2791 }
2792 ret = btrfs_free_chunk(trans, root, chunk_objectid, chunk_offset);
2793 if (ret) {
2794 btrfs_abort_transaction(trans, root, ret);
2795 goto out;
2796 }
2797
2798 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2799
2800 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2801 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2802 if (ret) {
2803 btrfs_abort_transaction(trans, root, ret);
2804 goto out;
2805 }
2806 }
2807
2808 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset, em);
2809 if (ret) {
2810 btrfs_abort_transaction(trans, extent_root, ret);
2811 goto out;
2812 }
2813
2814 out:
2815 /* once for us */
2816 free_extent_map(em);
2817 return ret;
2818 }
2819
2820 static int btrfs_relocate_chunk(struct btrfs_root *root, u64 chunk_offset)
2821 {
2822 struct btrfs_root *extent_root;
2823 struct btrfs_trans_handle *trans;
2824 int ret;
2825
2826 root = root->fs_info->chunk_root;
2827 extent_root = root->fs_info->extent_root;
2828
2829 /*
2830 * Prevent races with automatic removal of unused block groups.
2831 * After we relocate and before we remove the chunk with offset
2832 * chunk_offset, automatic removal of the block group can kick in,
2833 * resulting in a failure when calling btrfs_remove_chunk() below.
2834 *
2835 * Make sure to acquire this mutex before doing a tree search (dev
2836 * or chunk trees) to find chunks. Otherwise the cleaner kthread might
2837 * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after
2838 * we release the path used to search the chunk/dev tree and before
2839 * the current task acquires this mutex and calls us.
2840 */
2841 ASSERT(mutex_is_locked(&root->fs_info->delete_unused_bgs_mutex));
2842
2843 ret = btrfs_can_relocate(extent_root, chunk_offset);
2844 if (ret)
2845 return -ENOSPC;
2846
2847 /* step one, relocate all the extents inside this chunk */
2848 btrfs_scrub_pause(root);
2849 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2850 btrfs_scrub_continue(root);
2851 if (ret)
2852 return ret;
2853
2854 trans = btrfs_start_trans_remove_block_group(root->fs_info,
2855 chunk_offset);
2856 if (IS_ERR(trans)) {
2857 ret = PTR_ERR(trans);
2858 btrfs_std_error(root->fs_info, ret, NULL);
2859 return ret;
2860 }
2861
2862 /*
2863 * step two, delete the device extents and the
2864 * chunk tree entries
2865 */
2866 ret = btrfs_remove_chunk(trans, root, chunk_offset);
2867 btrfs_end_transaction(trans, root);
2868 return ret;
2869 }
2870
2871 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2872 {
2873 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2874 struct btrfs_path *path;
2875 struct extent_buffer *leaf;
2876 struct btrfs_chunk *chunk;
2877 struct btrfs_key key;
2878 struct btrfs_key found_key;
2879 u64 chunk_type;
2880 bool retried = false;
2881 int failed = 0;
2882 int ret;
2883
2884 path = btrfs_alloc_path();
2885 if (!path)
2886 return -ENOMEM;
2887
2888 again:
2889 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2890 key.offset = (u64)-1;
2891 key.type = BTRFS_CHUNK_ITEM_KEY;
2892
2893 while (1) {
2894 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
2895 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2896 if (ret < 0) {
2897 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2898 goto error;
2899 }
2900 BUG_ON(ret == 0); /* Corruption */
2901
2902 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2903 key.type);
2904 if (ret)
2905 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2906 if (ret < 0)
2907 goto error;
2908 if (ret > 0)
2909 break;
2910
2911 leaf = path->nodes[0];
2912 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2913
2914 chunk = btrfs_item_ptr(leaf, path->slots[0],
2915 struct btrfs_chunk);
2916 chunk_type = btrfs_chunk_type(leaf, chunk);
2917 btrfs_release_path(path);
2918
2919 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2920 ret = btrfs_relocate_chunk(chunk_root,
2921 found_key.offset);
2922 if (ret == -ENOSPC)
2923 failed++;
2924 else
2925 BUG_ON(ret);
2926 }
2927 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2928
2929 if (found_key.offset == 0)
2930 break;
2931 key.offset = found_key.offset - 1;
2932 }
2933 ret = 0;
2934 if (failed && !retried) {
2935 failed = 0;
2936 retried = true;
2937 goto again;
2938 } else if (WARN_ON(failed && retried)) {
2939 ret = -ENOSPC;
2940 }
2941 error:
2942 btrfs_free_path(path);
2943 return ret;
2944 }
2945
2946 static int insert_balance_item(struct btrfs_root *root,
2947 struct btrfs_balance_control *bctl)
2948 {
2949 struct btrfs_trans_handle *trans;
2950 struct btrfs_balance_item *item;
2951 struct btrfs_disk_balance_args disk_bargs;
2952 struct btrfs_path *path;
2953 struct extent_buffer *leaf;
2954 struct btrfs_key key;
2955 int ret, err;
2956
2957 path = btrfs_alloc_path();
2958 if (!path)
2959 return -ENOMEM;
2960
2961 trans = btrfs_start_transaction(root, 0);
2962 if (IS_ERR(trans)) {
2963 btrfs_free_path(path);
2964 return PTR_ERR(trans);
2965 }
2966
2967 key.objectid = BTRFS_BALANCE_OBJECTID;
2968 key.type = BTRFS_BALANCE_ITEM_KEY;
2969 key.offset = 0;
2970
2971 ret = btrfs_insert_empty_item(trans, root, path, &key,
2972 sizeof(*item));
2973 if (ret)
2974 goto out;
2975
2976 leaf = path->nodes[0];
2977 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2978
2979 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2980
2981 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2982 btrfs_set_balance_data(leaf, item, &disk_bargs);
2983 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2984 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2985 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2986 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2987
2988 btrfs_set_balance_flags(leaf, item, bctl->flags);
2989
2990 btrfs_mark_buffer_dirty(leaf);
2991 out:
2992 btrfs_free_path(path);
2993 err = btrfs_commit_transaction(trans, root);
2994 if (err && !ret)
2995 ret = err;
2996 return ret;
2997 }
2998
2999 static int del_balance_item(struct btrfs_root *root)
3000 {
3001 struct btrfs_trans_handle *trans;
3002 struct btrfs_path *path;
3003 struct btrfs_key key;
3004 int ret, err;
3005
3006 path = btrfs_alloc_path();
3007 if (!path)
3008 return -ENOMEM;
3009
3010 trans = btrfs_start_transaction(root, 0);
3011 if (IS_ERR(trans)) {
3012 btrfs_free_path(path);
3013 return PTR_ERR(trans);
3014 }
3015
3016 key.objectid = BTRFS_BALANCE_OBJECTID;
3017 key.type = BTRFS_BALANCE_ITEM_KEY;
3018 key.offset = 0;
3019
3020 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3021 if (ret < 0)
3022 goto out;
3023 if (ret > 0) {
3024 ret = -ENOENT;
3025 goto out;
3026 }
3027
3028 ret = btrfs_del_item(trans, root, path);
3029 out:
3030 btrfs_free_path(path);
3031 err = btrfs_commit_transaction(trans, root);
3032 if (err && !ret)
3033 ret = err;
3034 return ret;
3035 }
3036
3037 /*
3038 * This is a heuristic used to reduce the number of chunks balanced on
3039 * resume after balance was interrupted.
3040 */
3041 static void update_balance_args(struct btrfs_balance_control *bctl)
3042 {
3043 /*
3044 * Turn on soft mode for chunk types that were being converted.
3045 */
3046 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
3047 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
3048 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
3049 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
3050 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
3051 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
3052
3053 /*
3054 * Turn on usage filter if is not already used. The idea is
3055 * that chunks that we have already balanced should be
3056 * reasonably full. Don't do it for chunks that are being
3057 * converted - that will keep us from relocating unconverted
3058 * (albeit full) chunks.
3059 */
3060 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3061 !(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3062 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3063 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
3064 bctl->data.usage = 90;
3065 }
3066 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3067 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3068 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3069 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
3070 bctl->sys.usage = 90;
3071 }
3072 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3073 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3074 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3075 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
3076 bctl->meta.usage = 90;
3077 }
3078 }
3079
3080 /*
3081 * Should be called with both balance and volume mutexes held to
3082 * serialize other volume operations (add_dev/rm_dev/resize) with
3083 * restriper. Same goes for unset_balance_control.
3084 */
3085 static void set_balance_control(struct btrfs_balance_control *bctl)
3086 {
3087 struct btrfs_fs_info *fs_info = bctl->fs_info;
3088
3089 BUG_ON(fs_info->balance_ctl);
3090
3091 spin_lock(&fs_info->balance_lock);
3092 fs_info->balance_ctl = bctl;
3093 spin_unlock(&fs_info->balance_lock);
3094 }
3095
3096 static void unset_balance_control(struct btrfs_fs_info *fs_info)
3097 {
3098 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3099
3100 BUG_ON(!fs_info->balance_ctl);
3101
3102 spin_lock(&fs_info->balance_lock);
3103 fs_info->balance_ctl = NULL;
3104 spin_unlock(&fs_info->balance_lock);
3105
3106 kfree(bctl);
3107 }
3108
3109 /*
3110 * Balance filters. Return 1 if chunk should be filtered out
3111 * (should not be balanced).
3112 */
3113 static int chunk_profiles_filter(u64 chunk_type,
3114 struct btrfs_balance_args *bargs)
3115 {
3116 chunk_type = chunk_to_extended(chunk_type) &
3117 BTRFS_EXTENDED_PROFILE_MASK;
3118
3119 if (bargs->profiles & chunk_type)
3120 return 0;
3121
3122 return 1;
3123 }
3124
3125 static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
3126 struct btrfs_balance_args *bargs)
3127 {
3128 struct btrfs_block_group_cache *cache;
3129 u64 chunk_used;
3130 u64 user_thresh_min;
3131 u64 user_thresh_max;
3132 int ret = 1;
3133
3134 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3135 chunk_used = btrfs_block_group_used(&cache->item);
3136
3137 if (bargs->usage_min == 0)
3138 user_thresh_min = 0;
3139 else
3140 user_thresh_min = div_factor_fine(cache->key.offset,
3141 bargs->usage_min);
3142
3143 if (bargs->usage_max == 0)
3144 user_thresh_max = 1;
3145 else if (bargs->usage_max > 100)
3146 user_thresh_max = cache->key.offset;
3147 else
3148 user_thresh_max = div_factor_fine(cache->key.offset,
3149 bargs->usage_max);
3150
3151 if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max)
3152 ret = 0;
3153
3154 btrfs_put_block_group(cache);
3155 return ret;
3156 }
3157
3158 static int chunk_usage_filter(struct btrfs_fs_info *fs_info,
3159 u64 chunk_offset, struct btrfs_balance_args *bargs)
3160 {
3161 struct btrfs_block_group_cache *cache;
3162 u64 chunk_used, user_thresh;
3163 int ret = 1;
3164
3165 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3166 chunk_used = btrfs_block_group_used(&cache->item);
3167
3168 if (bargs->usage_min == 0)
3169 user_thresh = 1;
3170 else if (bargs->usage > 100)
3171 user_thresh = cache->key.offset;
3172 else
3173 user_thresh = div_factor_fine(cache->key.offset,
3174 bargs->usage);
3175
3176 if (chunk_used < user_thresh)
3177 ret = 0;
3178
3179 btrfs_put_block_group(cache);
3180 return ret;
3181 }
3182
3183 static int chunk_devid_filter(struct extent_buffer *leaf,
3184 struct btrfs_chunk *chunk,
3185 struct btrfs_balance_args *bargs)
3186 {
3187 struct btrfs_stripe *stripe;
3188 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3189 int i;
3190
3191 for (i = 0; i < num_stripes; i++) {
3192 stripe = btrfs_stripe_nr(chunk, i);
3193 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
3194 return 0;
3195 }
3196
3197 return 1;
3198 }
3199
3200 /* [pstart, pend) */
3201 static int chunk_drange_filter(struct extent_buffer *leaf,
3202 struct btrfs_chunk *chunk,
3203 u64 chunk_offset,
3204 struct btrfs_balance_args *bargs)
3205 {
3206 struct btrfs_stripe *stripe;
3207 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3208 u64 stripe_offset;
3209 u64 stripe_length;
3210 int factor;
3211 int i;
3212
3213 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3214 return 0;
3215
3216 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
3217 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
3218 factor = num_stripes / 2;
3219 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
3220 factor = num_stripes - 1;
3221 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
3222 factor = num_stripes - 2;
3223 } else {
3224 factor = num_stripes;
3225 }
3226
3227 for (i = 0; i < num_stripes; i++) {
3228 stripe = btrfs_stripe_nr(chunk, i);
3229 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3230 continue;
3231
3232 stripe_offset = btrfs_stripe_offset(leaf, stripe);
3233 stripe_length = btrfs_chunk_length(leaf, chunk);
3234 stripe_length = div_u64(stripe_length, factor);
3235
3236 if (stripe_offset < bargs->pend &&
3237 stripe_offset + stripe_length > bargs->pstart)
3238 return 0;
3239 }
3240
3241 return 1;
3242 }
3243
3244 /* [vstart, vend) */
3245 static int chunk_vrange_filter(struct extent_buffer *leaf,
3246 struct btrfs_chunk *chunk,
3247 u64 chunk_offset,
3248 struct btrfs_balance_args *bargs)
3249 {
3250 if (chunk_offset < bargs->vend &&
3251 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
3252 /* at least part of the chunk is inside this vrange */
3253 return 0;
3254
3255 return 1;
3256 }
3257
3258 static int chunk_stripes_range_filter(struct extent_buffer *leaf,
3259 struct btrfs_chunk *chunk,
3260 struct btrfs_balance_args *bargs)
3261 {
3262 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3263
3264 if (bargs->stripes_min <= num_stripes
3265 && num_stripes <= bargs->stripes_max)
3266 return 0;
3267
3268 return 1;
3269 }
3270
3271 static int chunk_soft_convert_filter(u64 chunk_type,
3272 struct btrfs_balance_args *bargs)
3273 {
3274 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
3275 return 0;
3276
3277 chunk_type = chunk_to_extended(chunk_type) &
3278 BTRFS_EXTENDED_PROFILE_MASK;
3279
3280 if (bargs->target == chunk_type)
3281 return 1;
3282
3283 return 0;
3284 }
3285
3286 static int should_balance_chunk(struct btrfs_root *root,
3287 struct extent_buffer *leaf,
3288 struct btrfs_chunk *chunk, u64 chunk_offset)
3289 {
3290 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
3291 struct btrfs_balance_args *bargs = NULL;
3292 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
3293
3294 /* type filter */
3295 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
3296 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
3297 return 0;
3298 }
3299
3300 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3301 bargs = &bctl->data;
3302 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3303 bargs = &bctl->sys;
3304 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3305 bargs = &bctl->meta;
3306
3307 /* profiles filter */
3308 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
3309 chunk_profiles_filter(chunk_type, bargs)) {
3310 return 0;
3311 }
3312
3313 /* usage filter */
3314 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
3315 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
3316 return 0;
3317 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3318 chunk_usage_range_filter(bctl->fs_info, chunk_offset, bargs)) {
3319 return 0;
3320 }
3321
3322 /* devid filter */
3323 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
3324 chunk_devid_filter(leaf, chunk, bargs)) {
3325 return 0;
3326 }
3327
3328 /* drange filter, makes sense only with devid filter */
3329 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
3330 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
3331 return 0;
3332 }
3333
3334 /* vrange filter */
3335 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
3336 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
3337 return 0;
3338 }
3339
3340 /* stripes filter */
3341 if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) &&
3342 chunk_stripes_range_filter(leaf, chunk, bargs)) {
3343 return 0;
3344 }
3345
3346 /* soft profile changing mode */
3347 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
3348 chunk_soft_convert_filter(chunk_type, bargs)) {
3349 return 0;
3350 }
3351
3352 /*
3353 * limited by count, must be the last filter
3354 */
3355 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
3356 if (bargs->limit == 0)
3357 return 0;
3358 else
3359 bargs->limit--;
3360 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) {
3361 /*
3362 * Same logic as the 'limit' filter; the minimum cannot be
3363 * determined here because we do not have the global informatoin
3364 * about the count of all chunks that satisfy the filters.
3365 */
3366 if (bargs->limit_max == 0)
3367 return 0;
3368 else
3369 bargs->limit_max--;
3370 }
3371
3372 return 1;
3373 }
3374
3375 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
3376 {
3377 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3378 struct btrfs_root *chunk_root = fs_info->chunk_root;
3379 struct btrfs_root *dev_root = fs_info->dev_root;
3380 struct list_head *devices;
3381 struct btrfs_device *device;
3382 u64 old_size;
3383 u64 size_to_free;
3384 u64 chunk_type;
3385 struct btrfs_chunk *chunk;
3386 struct btrfs_path *path;
3387 struct btrfs_key key;
3388 struct btrfs_key found_key;
3389 struct btrfs_trans_handle *trans;
3390 struct extent_buffer *leaf;
3391 int slot;
3392 int ret;
3393 int enospc_errors = 0;
3394 bool counting = true;
3395 /* The single value limit and min/max limits use the same bytes in the */
3396 u64 limit_data = bctl->data.limit;
3397 u64 limit_meta = bctl->meta.limit;
3398 u64 limit_sys = bctl->sys.limit;
3399 u32 count_data = 0;
3400 u32 count_meta = 0;
3401 u32 count_sys = 0;
3402 int chunk_reserved = 0;
3403
3404 /* step one make some room on all the devices */
3405 devices = &fs_info->fs_devices->devices;
3406 list_for_each_entry(device, devices, dev_list) {
3407 old_size = btrfs_device_get_total_bytes(device);
3408 size_to_free = div_factor(old_size, 1);
3409 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
3410 if (!device->writeable ||
3411 btrfs_device_get_total_bytes(device) -
3412 btrfs_device_get_bytes_used(device) > size_to_free ||
3413 device->is_tgtdev_for_dev_replace)
3414 continue;
3415
3416 ret = btrfs_shrink_device(device, old_size - size_to_free);
3417 if (ret == -ENOSPC)
3418 break;
3419 BUG_ON(ret);
3420
3421 trans = btrfs_start_transaction(dev_root, 0);
3422 BUG_ON(IS_ERR(trans));
3423
3424 ret = btrfs_grow_device(trans, device, old_size);
3425 BUG_ON(ret);
3426
3427 btrfs_end_transaction(trans, dev_root);
3428 }
3429
3430 /* step two, relocate all the chunks */
3431 path = btrfs_alloc_path();
3432 if (!path) {
3433 ret = -ENOMEM;
3434 goto error;
3435 }
3436
3437 /* zero out stat counters */
3438 spin_lock(&fs_info->balance_lock);
3439 memset(&bctl->stat, 0, sizeof(bctl->stat));
3440 spin_unlock(&fs_info->balance_lock);
3441 again:
3442 if (!counting) {
3443 /*
3444 * The single value limit and min/max limits use the same bytes
3445 * in the
3446 */
3447 bctl->data.limit = limit_data;
3448 bctl->meta.limit = limit_meta;
3449 bctl->sys.limit = limit_sys;
3450 }
3451 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3452 key.offset = (u64)-1;
3453 key.type = BTRFS_CHUNK_ITEM_KEY;
3454
3455 while (1) {
3456 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
3457 atomic_read(&fs_info->balance_cancel_req)) {
3458 ret = -ECANCELED;
3459 goto error;
3460 }
3461
3462 mutex_lock(&fs_info->delete_unused_bgs_mutex);
3463 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3464 if (ret < 0) {
3465 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3466 goto error;
3467 }
3468
3469 /*
3470 * this shouldn't happen, it means the last relocate
3471 * failed
3472 */
3473 if (ret == 0)
3474 BUG(); /* FIXME break ? */
3475
3476 ret = btrfs_previous_item(chunk_root, path, 0,
3477 BTRFS_CHUNK_ITEM_KEY);
3478 if (ret) {
3479 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3480 ret = 0;
3481 break;
3482 }
3483
3484 leaf = path->nodes[0];
3485 slot = path->slots[0];
3486 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3487
3488 if (found_key.objectid != key.objectid) {
3489 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3490 break;
3491 }
3492
3493 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3494 chunk_type = btrfs_chunk_type(leaf, chunk);
3495
3496 if (!counting) {
3497 spin_lock(&fs_info->balance_lock);
3498 bctl->stat.considered++;
3499 spin_unlock(&fs_info->balance_lock);
3500 }
3501
3502 ret = should_balance_chunk(chunk_root, leaf, chunk,
3503 found_key.offset);
3504
3505 btrfs_release_path(path);
3506 if (!ret) {
3507 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3508 goto loop;
3509 }
3510
3511 if (counting) {
3512 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3513 spin_lock(&fs_info->balance_lock);
3514 bctl->stat.expected++;
3515 spin_unlock(&fs_info->balance_lock);
3516
3517 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3518 count_data++;
3519 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3520 count_sys++;
3521 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3522 count_meta++;
3523
3524 goto loop;
3525 }
3526
3527 /*
3528 * Apply limit_min filter, no need to check if the LIMITS
3529 * filter is used, limit_min is 0 by default
3530 */
3531 if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
3532 count_data < bctl->data.limit_min)
3533 || ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) &&
3534 count_meta < bctl->meta.limit_min)
3535 || ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) &&
3536 count_sys < bctl->sys.limit_min)) {
3537 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3538 goto loop;
3539 }
3540
3541 if ((chunk_type & BTRFS_BLOCK_GROUP_DATA) && !chunk_reserved) {
3542 trans = btrfs_start_transaction(chunk_root, 0);
3543 if (IS_ERR(trans)) {
3544 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3545 ret = PTR_ERR(trans);
3546 goto error;
3547 }
3548
3549 ret = btrfs_force_chunk_alloc(trans, chunk_root,
3550 BTRFS_BLOCK_GROUP_DATA);
3551 if (ret < 0) {
3552 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3553 goto error;
3554 }
3555
3556 btrfs_end_transaction(trans, chunk_root);
3557 chunk_reserved = 1;
3558 }
3559
3560 ret = btrfs_relocate_chunk(chunk_root,
3561 found_key.offset);
3562 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3563 if (ret && ret != -ENOSPC)
3564 goto error;
3565 if (ret == -ENOSPC) {
3566 enospc_errors++;
3567 } else {
3568 spin_lock(&fs_info->balance_lock);
3569 bctl->stat.completed++;
3570 spin_unlock(&fs_info->balance_lock);
3571 }
3572 loop:
3573 if (found_key.offset == 0)
3574 break;
3575 key.offset = found_key.offset - 1;
3576 }
3577
3578 if (counting) {
3579 btrfs_release_path(path);
3580 counting = false;
3581 goto again;
3582 }
3583 error:
3584 btrfs_free_path(path);
3585 if (enospc_errors) {
3586 btrfs_info(fs_info, "%d enospc errors during balance",
3587 enospc_errors);
3588 if (!ret)
3589 ret = -ENOSPC;
3590 }
3591
3592 return ret;
3593 }
3594
3595 /**
3596 * alloc_profile_is_valid - see if a given profile is valid and reduced
3597 * @flags: profile to validate
3598 * @extended: if true @flags is treated as an extended profile
3599 */
3600 static int alloc_profile_is_valid(u64 flags, int extended)
3601 {
3602 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
3603 BTRFS_BLOCK_GROUP_PROFILE_MASK);
3604
3605 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
3606
3607 /* 1) check that all other bits are zeroed */
3608 if (flags & ~mask)
3609 return 0;
3610
3611 /* 2) see if profile is reduced */
3612 if (flags == 0)
3613 return !extended; /* "0" is valid for usual profiles */
3614
3615 /* true if exactly one bit set */
3616 return (flags & (flags - 1)) == 0;
3617 }
3618
3619 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
3620 {
3621 /* cancel requested || normal exit path */
3622 return atomic_read(&fs_info->balance_cancel_req) ||
3623 (atomic_read(&fs_info->balance_pause_req) == 0 &&
3624 atomic_read(&fs_info->balance_cancel_req) == 0);
3625 }
3626
3627 static void __cancel_balance(struct btrfs_fs_info *fs_info)
3628 {
3629 int ret;
3630
3631 unset_balance_control(fs_info);
3632 ret = del_balance_item(fs_info->tree_root);
3633 if (ret)
3634 btrfs_std_error(fs_info, ret, NULL);
3635
3636 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3637 }
3638
3639 /* Non-zero return value signifies invalidity */
3640 static inline int validate_convert_profile(struct btrfs_balance_args *bctl_arg,
3641 u64 allowed)
3642 {
3643 return ((bctl_arg->flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3644 (!alloc_profile_is_valid(bctl_arg->target, 1) ||
3645 (bctl_arg->target & ~allowed)));
3646 }
3647
3648 /*
3649 * Should be called with both balance and volume mutexes held
3650 */
3651 int btrfs_balance(struct btrfs_balance_control *bctl,
3652 struct btrfs_ioctl_balance_args *bargs)
3653 {
3654 struct btrfs_fs_info *fs_info = bctl->fs_info;
3655 u64 allowed;
3656 int mixed = 0;
3657 int ret;
3658 u64 num_devices;
3659 unsigned seq;
3660
3661 if (btrfs_fs_closing(fs_info) ||
3662 atomic_read(&fs_info->balance_pause_req) ||
3663 atomic_read(&fs_info->balance_cancel_req)) {
3664 ret = -EINVAL;
3665 goto out;
3666 }
3667
3668 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3669 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3670 mixed = 1;
3671
3672 /*
3673 * In case of mixed groups both data and meta should be picked,
3674 * and identical options should be given for both of them.
3675 */
3676 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3677 if (mixed && (bctl->flags & allowed)) {
3678 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3679 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3680 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3681 btrfs_err(fs_info, "with mixed groups data and "
3682 "metadata balance options must be the same");
3683 ret = -EINVAL;
3684 goto out;
3685 }
3686 }
3687
3688 num_devices = fs_info->fs_devices->num_devices;
3689 btrfs_dev_replace_lock(&fs_info->dev_replace);
3690 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3691 BUG_ON(num_devices < 1);
3692 num_devices--;
3693 }
3694 btrfs_dev_replace_unlock(&fs_info->dev_replace);
3695 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3696 if (num_devices == 1)
3697 allowed |= BTRFS_BLOCK_GROUP_DUP;
3698 else if (num_devices > 1)
3699 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3700 if (num_devices > 2)
3701 allowed |= BTRFS_BLOCK_GROUP_RAID5;
3702 if (num_devices > 3)
3703 allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
3704 BTRFS_BLOCK_GROUP_RAID6);
3705 if (validate_convert_profile(&bctl->data, allowed)) {
3706 btrfs_err(fs_info, "unable to start balance with target "
3707 "data profile %llu",
3708 bctl->data.target);
3709 ret = -EINVAL;
3710 goto out;
3711 }
3712 if (validate_convert_profile(&bctl->meta, allowed)) {
3713 btrfs_err(fs_info,
3714 "unable to start balance with target metadata profile %llu",
3715 bctl->meta.target);
3716 ret = -EINVAL;
3717 goto out;
3718 }
3719 if (validate_convert_profile(&bctl->sys, allowed)) {
3720 btrfs_err(fs_info,
3721 "unable to start balance with target system profile %llu",
3722 bctl->sys.target);
3723 ret = -EINVAL;
3724 goto out;
3725 }
3726
3727 /* allow dup'ed data chunks only in mixed mode */
3728 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3729 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
3730 btrfs_err(fs_info, "dup for data is not allowed");
3731 ret = -EINVAL;
3732 goto out;
3733 }
3734
3735 /* allow to reduce meta or sys integrity only if force set */
3736 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3737 BTRFS_BLOCK_GROUP_RAID10 |
3738 BTRFS_BLOCK_GROUP_RAID5 |
3739 BTRFS_BLOCK_GROUP_RAID6;
3740 do {
3741 seq = read_seqbegin(&fs_info->profiles_lock);
3742
3743 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3744 (fs_info->avail_system_alloc_bits & allowed) &&
3745 !(bctl->sys.target & allowed)) ||
3746 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3747 (fs_info->avail_metadata_alloc_bits & allowed) &&
3748 !(bctl->meta.target & allowed))) {
3749 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3750 btrfs_info(fs_info, "force reducing metadata integrity");
3751 } else {
3752 btrfs_err(fs_info, "balance will reduce metadata "
3753 "integrity, use force if you want this");
3754 ret = -EINVAL;
3755 goto out;
3756 }
3757 }
3758 } while (read_seqretry(&fs_info->profiles_lock, seq));
3759
3760 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3761 fs_info->num_tolerated_disk_barrier_failures = min(
3762 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info),
3763 btrfs_get_num_tolerated_disk_barrier_failures(
3764 bctl->sys.target));
3765 }
3766
3767 ret = insert_balance_item(fs_info->tree_root, bctl);
3768 if (ret && ret != -EEXIST)
3769 goto out;
3770
3771 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3772 BUG_ON(ret == -EEXIST);
3773 set_balance_control(bctl);
3774 } else {
3775 BUG_ON(ret != -EEXIST);
3776 spin_lock(&fs_info->balance_lock);
3777 update_balance_args(bctl);
3778 spin_unlock(&fs_info->balance_lock);
3779 }
3780
3781 atomic_inc(&fs_info->balance_running);
3782 mutex_unlock(&fs_info->balance_mutex);
3783
3784 ret = __btrfs_balance(fs_info);
3785
3786 mutex_lock(&fs_info->balance_mutex);
3787 atomic_dec(&fs_info->balance_running);
3788
3789 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3790 fs_info->num_tolerated_disk_barrier_failures =
3791 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3792 }
3793
3794 if (bargs) {
3795 memset(bargs, 0, sizeof(*bargs));
3796 update_ioctl_balance_args(fs_info, 0, bargs);
3797 }
3798
3799 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3800 balance_need_close(fs_info)) {
3801 __cancel_balance(fs_info);
3802 }
3803
3804 wake_up(&fs_info->balance_wait_q);
3805
3806 return ret;
3807 out:
3808 if (bctl->flags & BTRFS_BALANCE_RESUME)
3809 __cancel_balance(fs_info);
3810 else {
3811 kfree(bctl);
3812 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3813 }
3814 return ret;
3815 }
3816
3817 static int balance_kthread(void *data)
3818 {
3819 struct btrfs_fs_info *fs_info = data;
3820 int ret = 0;
3821
3822 mutex_lock(&fs_info->volume_mutex);
3823 mutex_lock(&fs_info->balance_mutex);
3824
3825 if (fs_info->balance_ctl) {
3826 btrfs_info(fs_info, "continuing balance");
3827 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3828 }
3829
3830 mutex_unlock(&fs_info->balance_mutex);
3831 mutex_unlock(&fs_info->volume_mutex);
3832
3833 return ret;
3834 }
3835
3836 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3837 {
3838 struct task_struct *tsk;
3839
3840 spin_lock(&fs_info->balance_lock);
3841 if (!fs_info->balance_ctl) {
3842 spin_unlock(&fs_info->balance_lock);
3843 return 0;
3844 }
3845 spin_unlock(&fs_info->balance_lock);
3846
3847 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3848 btrfs_info(fs_info, "force skipping balance");
3849 return 0;
3850 }
3851
3852 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3853 return PTR_ERR_OR_ZERO(tsk);
3854 }
3855
3856 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3857 {
3858 struct btrfs_balance_control *bctl;
3859 struct btrfs_balance_item *item;
3860 struct btrfs_disk_balance_args disk_bargs;
3861 struct btrfs_path *path;
3862 struct extent_buffer *leaf;
3863 struct btrfs_key key;
3864 int ret;
3865
3866 path = btrfs_alloc_path();
3867 if (!path)
3868 return -ENOMEM;
3869
3870 key.objectid = BTRFS_BALANCE_OBJECTID;
3871 key.type = BTRFS_BALANCE_ITEM_KEY;
3872 key.offset = 0;
3873
3874 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3875 if (ret < 0)
3876 goto out;
3877 if (ret > 0) { /* ret = -ENOENT; */
3878 ret = 0;
3879 goto out;
3880 }
3881
3882 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3883 if (!bctl) {
3884 ret = -ENOMEM;
3885 goto out;
3886 }
3887
3888 leaf = path->nodes[0];
3889 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3890
3891 bctl->fs_info = fs_info;
3892 bctl->flags = btrfs_balance_flags(leaf, item);
3893 bctl->flags |= BTRFS_BALANCE_RESUME;
3894
3895 btrfs_balance_data(leaf, item, &disk_bargs);
3896 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3897 btrfs_balance_meta(leaf, item, &disk_bargs);
3898 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3899 btrfs_balance_sys(leaf, item, &disk_bargs);
3900 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3901
3902 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3903
3904 mutex_lock(&fs_info->volume_mutex);
3905 mutex_lock(&fs_info->balance_mutex);
3906
3907 set_balance_control(bctl);
3908
3909 mutex_unlock(&fs_info->balance_mutex);
3910 mutex_unlock(&fs_info->volume_mutex);
3911 out:
3912 btrfs_free_path(path);
3913 return ret;
3914 }
3915
3916 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3917 {
3918 int ret = 0;
3919
3920 mutex_lock(&fs_info->balance_mutex);
3921 if (!fs_info->balance_ctl) {
3922 mutex_unlock(&fs_info->balance_mutex);
3923 return -ENOTCONN;
3924 }
3925
3926 if (atomic_read(&fs_info->balance_running)) {
3927 atomic_inc(&fs_info->balance_pause_req);
3928 mutex_unlock(&fs_info->balance_mutex);
3929
3930 wait_event(fs_info->balance_wait_q,
3931 atomic_read(&fs_info->balance_running) == 0);
3932
3933 mutex_lock(&fs_info->balance_mutex);
3934 /* we are good with balance_ctl ripped off from under us */
3935 BUG_ON(atomic_read(&fs_info->balance_running));
3936 atomic_dec(&fs_info->balance_pause_req);
3937 } else {
3938 ret = -ENOTCONN;
3939 }
3940
3941 mutex_unlock(&fs_info->balance_mutex);
3942 return ret;
3943 }
3944
3945 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3946 {
3947 if (fs_info->sb->s_flags & MS_RDONLY)
3948 return -EROFS;
3949
3950 mutex_lock(&fs_info->balance_mutex);
3951 if (!fs_info->balance_ctl) {
3952 mutex_unlock(&fs_info->balance_mutex);
3953 return -ENOTCONN;
3954 }
3955
3956 atomic_inc(&fs_info->balance_cancel_req);
3957 /*
3958 * if we are running just wait and return, balance item is
3959 * deleted in btrfs_balance in this case
3960 */
3961 if (atomic_read(&fs_info->balance_running)) {
3962 mutex_unlock(&fs_info->balance_mutex);
3963 wait_event(fs_info->balance_wait_q,
3964 atomic_read(&fs_info->balance_running) == 0);
3965 mutex_lock(&fs_info->balance_mutex);
3966 } else {
3967 /* __cancel_balance needs volume_mutex */
3968 mutex_unlock(&fs_info->balance_mutex);
3969 mutex_lock(&fs_info->volume_mutex);
3970 mutex_lock(&fs_info->balance_mutex);
3971
3972 if (fs_info->balance_ctl)
3973 __cancel_balance(fs_info);
3974
3975 mutex_unlock(&fs_info->volume_mutex);
3976 }
3977
3978 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
3979 atomic_dec(&fs_info->balance_cancel_req);
3980 mutex_unlock(&fs_info->balance_mutex);
3981 return 0;
3982 }
3983
3984 static int btrfs_uuid_scan_kthread(void *data)
3985 {
3986 struct btrfs_fs_info *fs_info = data;
3987 struct btrfs_root *root = fs_info->tree_root;
3988 struct btrfs_key key;
3989 struct btrfs_key max_key;
3990 struct btrfs_path *path = NULL;
3991 int ret = 0;
3992 struct extent_buffer *eb;
3993 int slot;
3994 struct btrfs_root_item root_item;
3995 u32 item_size;
3996 struct btrfs_trans_handle *trans = NULL;
3997
3998 path = btrfs_alloc_path();
3999 if (!path) {
4000 ret = -ENOMEM;
4001 goto out;
4002 }
4003
4004 key.objectid = 0;
4005 key.type = BTRFS_ROOT_ITEM_KEY;
4006 key.offset = 0;
4007
4008 max_key.objectid = (u64)-1;
4009 max_key.type = BTRFS_ROOT_ITEM_KEY;
4010 max_key.offset = (u64)-1;
4011
4012 while (1) {
4013 ret = btrfs_search_forward(root, &key, path, 0);
4014 if (ret) {
4015 if (ret > 0)
4016 ret = 0;
4017 break;
4018 }
4019
4020 if (key.type != BTRFS_ROOT_ITEM_KEY ||
4021 (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
4022 key.objectid != BTRFS_FS_TREE_OBJECTID) ||
4023 key.objectid > BTRFS_LAST_FREE_OBJECTID)
4024 goto skip;
4025
4026 eb = path->nodes[0];
4027 slot = path->slots[0];
4028 item_size = btrfs_item_size_nr(eb, slot);
4029 if (item_size < sizeof(root_item))
4030 goto skip;
4031
4032 read_extent_buffer(eb, &root_item,
4033 btrfs_item_ptr_offset(eb, slot),
4034 (int)sizeof(root_item));
4035 if (btrfs_root_refs(&root_item) == 0)
4036 goto skip;
4037
4038 if (!btrfs_is_empty_uuid(root_item.uuid) ||
4039 !btrfs_is_empty_uuid(root_item.received_uuid)) {
4040 if (trans)
4041 goto update_tree;
4042
4043 btrfs_release_path(path);
4044 /*
4045 * 1 - subvol uuid item
4046 * 1 - received_subvol uuid item
4047 */
4048 trans = btrfs_start_transaction(fs_info->uuid_root, 2);
4049 if (IS_ERR(trans)) {
4050 ret = PTR_ERR(trans);
4051 break;
4052 }
4053 continue;
4054 } else {
4055 goto skip;
4056 }
4057 update_tree:
4058 if (!btrfs_is_empty_uuid(root_item.uuid)) {
4059 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
4060 root_item.uuid,
4061 BTRFS_UUID_KEY_SUBVOL,
4062 key.objectid);
4063 if (ret < 0) {
4064 btrfs_warn(fs_info, "uuid_tree_add failed %d",
4065 ret);
4066 break;
4067 }
4068 }
4069
4070 if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
4071 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
4072 root_item.received_uuid,
4073 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4074 key.objectid);
4075 if (ret < 0) {
4076 btrfs_warn(fs_info, "uuid_tree_add failed %d",
4077 ret);
4078 break;
4079 }
4080 }
4081
4082 skip:
4083 if (trans) {
4084 ret = btrfs_end_transaction(trans, fs_info->uuid_root);
4085 trans = NULL;
4086 if (ret)
4087 break;
4088 }
4089
4090 btrfs_release_path(path);
4091 if (key.offset < (u64)-1) {
4092 key.offset++;
4093 } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
4094 key.offset = 0;
4095 key.type = BTRFS_ROOT_ITEM_KEY;
4096 } else if (key.objectid < (u64)-1) {
4097 key.offset = 0;
4098 key.type = BTRFS_ROOT_ITEM_KEY;
4099 key.objectid++;
4100 } else {
4101 break;
4102 }
4103 cond_resched();
4104 }
4105
4106 out:
4107 btrfs_free_path(path);
4108 if (trans && !IS_ERR(trans))
4109 btrfs_end_transaction(trans, fs_info->uuid_root);
4110 if (ret)
4111 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
4112 else
4113 fs_info->update_uuid_tree_gen = 1;
4114 up(&fs_info->uuid_tree_rescan_sem);
4115 return 0;
4116 }
4117
4118 /*
4119 * Callback for btrfs_uuid_tree_iterate().
4120 * returns:
4121 * 0 check succeeded, the entry is not outdated.
4122 * < 0 if an error occured.
4123 * > 0 if the check failed, which means the caller shall remove the entry.
4124 */
4125 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
4126 u8 *uuid, u8 type, u64 subid)
4127 {
4128 struct btrfs_key key;
4129 int ret = 0;
4130 struct btrfs_root *subvol_root;
4131
4132 if (type != BTRFS_UUID_KEY_SUBVOL &&
4133 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
4134 goto out;
4135
4136 key.objectid = subid;
4137 key.type = BTRFS_ROOT_ITEM_KEY;
4138 key.offset = (u64)-1;
4139 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
4140 if (IS_ERR(subvol_root)) {
4141 ret = PTR_ERR(subvol_root);
4142 if (ret == -ENOENT)
4143 ret = 1;
4144 goto out;
4145 }
4146
4147 switch (type) {
4148 case BTRFS_UUID_KEY_SUBVOL:
4149 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
4150 ret = 1;
4151 break;
4152 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
4153 if (memcmp(uuid, subvol_root->root_item.received_uuid,
4154 BTRFS_UUID_SIZE))
4155 ret = 1;
4156 break;
4157 }
4158
4159 out:
4160 return ret;
4161 }
4162
4163 static int btrfs_uuid_rescan_kthread(void *data)
4164 {
4165 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
4166 int ret;
4167
4168 /*
4169 * 1st step is to iterate through the existing UUID tree and
4170 * to delete all entries that contain outdated data.
4171 * 2nd step is to add all missing entries to the UUID tree.
4172 */
4173 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
4174 if (ret < 0) {
4175 btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
4176 up(&fs_info->uuid_tree_rescan_sem);
4177 return ret;
4178 }
4179 return btrfs_uuid_scan_kthread(data);
4180 }
4181
4182 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
4183 {
4184 struct btrfs_trans_handle *trans;
4185 struct btrfs_root *tree_root = fs_info->tree_root;
4186 struct btrfs_root *uuid_root;
4187 struct task_struct *task;
4188 int ret;
4189
4190 /*
4191 * 1 - root node
4192 * 1 - root item
4193 */
4194 trans = btrfs_start_transaction(tree_root, 2);
4195 if (IS_ERR(trans))
4196 return PTR_ERR(trans);
4197
4198 uuid_root = btrfs_create_tree(trans, fs_info,
4199 BTRFS_UUID_TREE_OBJECTID);
4200 if (IS_ERR(uuid_root)) {
4201 ret = PTR_ERR(uuid_root);
4202 btrfs_abort_transaction(trans, tree_root, ret);
4203 return ret;
4204 }
4205
4206 fs_info->uuid_root = uuid_root;
4207
4208 ret = btrfs_commit_transaction(trans, tree_root);
4209 if (ret)
4210 return ret;
4211
4212 down(&fs_info->uuid_tree_rescan_sem);
4213 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
4214 if (IS_ERR(task)) {
4215 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
4216 btrfs_warn(fs_info, "failed to start uuid_scan task");
4217 up(&fs_info->uuid_tree_rescan_sem);
4218 return PTR_ERR(task);
4219 }
4220
4221 return 0;
4222 }
4223
4224 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
4225 {
4226 struct task_struct *task;
4227
4228 down(&fs_info->uuid_tree_rescan_sem);
4229 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
4230 if (IS_ERR(task)) {
4231 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
4232 btrfs_warn(fs_info, "failed to start uuid_rescan task");
4233 up(&fs_info->uuid_tree_rescan_sem);
4234 return PTR_ERR(task);
4235 }
4236
4237 return 0;
4238 }
4239
4240 /*
4241 * shrinking a device means finding all of the device extents past
4242 * the new size, and then following the back refs to the chunks.
4243 * The chunk relocation code actually frees the device extent
4244 */
4245 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
4246 {
4247 struct btrfs_trans_handle *trans;
4248 struct btrfs_root *root = device->dev_root;
4249 struct btrfs_dev_extent *dev_extent = NULL;
4250 struct btrfs_path *path;
4251 u64 length;
4252 u64 chunk_offset;
4253 int ret;
4254 int slot;
4255 int failed = 0;
4256 bool retried = false;
4257 bool checked_pending_chunks = false;
4258 struct extent_buffer *l;
4259 struct btrfs_key key;
4260 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4261 u64 old_total = btrfs_super_total_bytes(super_copy);
4262 u64 old_size = btrfs_device_get_total_bytes(device);
4263 u64 diff = old_size - new_size;
4264
4265 if (device->is_tgtdev_for_dev_replace)
4266 return -EINVAL;
4267
4268 path = btrfs_alloc_path();
4269 if (!path)
4270 return -ENOMEM;
4271
4272 path->reada = 2;
4273
4274 lock_chunks(root);
4275
4276 btrfs_device_set_total_bytes(device, new_size);
4277 if (device->writeable) {
4278 device->fs_devices->total_rw_bytes -= diff;
4279 spin_lock(&root->fs_info->free_chunk_lock);
4280 root->fs_info->free_chunk_space -= diff;
4281 spin_unlock(&root->fs_info->free_chunk_lock);
4282 }
4283 unlock_chunks(root);
4284
4285 again:
4286 key.objectid = device->devid;
4287 key.offset = (u64)-1;
4288 key.type = BTRFS_DEV_EXTENT_KEY;
4289
4290 do {
4291 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
4292 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4293 if (ret < 0) {
4294 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4295 goto done;
4296 }
4297
4298 ret = btrfs_previous_item(root, path, 0, key.type);
4299 if (ret)
4300 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4301 if (ret < 0)
4302 goto done;
4303 if (ret) {
4304 ret = 0;
4305 btrfs_release_path(path);
4306 break;
4307 }
4308
4309 l = path->nodes[0];
4310 slot = path->slots[0];
4311 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
4312
4313 if (key.objectid != device->devid) {
4314 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4315 btrfs_release_path(path);
4316 break;
4317 }
4318
4319 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
4320 length = btrfs_dev_extent_length(l, dev_extent);
4321
4322 if (key.offset + length <= new_size) {
4323 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4324 btrfs_release_path(path);
4325 break;
4326 }
4327
4328 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
4329 btrfs_release_path(path);
4330
4331 ret = btrfs_relocate_chunk(root, chunk_offset);
4332 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4333 if (ret && ret != -ENOSPC)
4334 goto done;
4335 if (ret == -ENOSPC)
4336 failed++;
4337 } while (key.offset-- > 0);
4338
4339 if (failed && !retried) {
4340 failed = 0;
4341 retried = true;
4342 goto again;
4343 } else if (failed && retried) {
4344 ret = -ENOSPC;
4345 goto done;
4346 }
4347
4348 /* Shrinking succeeded, else we would be at "done". */
4349 trans = btrfs_start_transaction(root, 0);
4350 if (IS_ERR(trans)) {
4351 ret = PTR_ERR(trans);
4352 goto done;
4353 }
4354
4355 lock_chunks(root);
4356
4357 /*
4358 * We checked in the above loop all device extents that were already in
4359 * the device tree. However before we have updated the device's
4360 * total_bytes to the new size, we might have had chunk allocations that
4361 * have not complete yet (new block groups attached to transaction
4362 * handles), and therefore their device extents were not yet in the
4363 * device tree and we missed them in the loop above. So if we have any
4364 * pending chunk using a device extent that overlaps the device range
4365 * that we can not use anymore, commit the current transaction and
4366 * repeat the search on the device tree - this way we guarantee we will
4367 * not have chunks using device extents that end beyond 'new_size'.
4368 */
4369 if (!checked_pending_chunks) {
4370 u64 start = new_size;
4371 u64 len = old_size - new_size;
4372
4373 if (contains_pending_extent(trans->transaction, device,
4374 &start, len)) {
4375 unlock_chunks(root);
4376 checked_pending_chunks = true;
4377 failed = 0;
4378 retried = false;
4379 ret = btrfs_commit_transaction(trans, root);
4380 if (ret)
4381 goto done;
4382 goto again;
4383 }
4384 }
4385
4386 btrfs_device_set_disk_total_bytes(device, new_size);
4387 if (list_empty(&device->resized_list))
4388 list_add_tail(&device->resized_list,
4389 &root->fs_info->fs_devices->resized_devices);
4390
4391 WARN_ON(diff > old_total);
4392 btrfs_set_super_total_bytes(super_copy, old_total - diff);
4393 unlock_chunks(root);
4394
4395 /* Now btrfs_update_device() will change the on-disk size. */
4396 ret = btrfs_update_device(trans, device);
4397 btrfs_end_transaction(trans, root);
4398 done:
4399 btrfs_free_path(path);
4400 if (ret) {
4401 lock_chunks(root);
4402 btrfs_device_set_total_bytes(device, old_size);
4403 if (device->writeable)
4404 device->fs_devices->total_rw_bytes += diff;
4405 spin_lock(&root->fs_info->free_chunk_lock);
4406 root->fs_info->free_chunk_space += diff;
4407 spin_unlock(&root->fs_info->free_chunk_lock);
4408 unlock_chunks(root);
4409 }
4410 return ret;
4411 }
4412
4413 static int btrfs_add_system_chunk(struct btrfs_root *root,
4414 struct btrfs_key *key,
4415 struct btrfs_chunk *chunk, int item_size)
4416 {
4417 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4418 struct btrfs_disk_key disk_key;
4419 u32 array_size;
4420 u8 *ptr;
4421
4422 lock_chunks(root);
4423 array_size = btrfs_super_sys_array_size(super_copy);
4424 if (array_size + item_size + sizeof(disk_key)
4425 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
4426 unlock_chunks(root);
4427 return -EFBIG;
4428 }
4429
4430 ptr = super_copy->sys_chunk_array + array_size;
4431 btrfs_cpu_key_to_disk(&disk_key, key);
4432 memcpy(ptr, &disk_key, sizeof(disk_key));
4433 ptr += sizeof(disk_key);
4434 memcpy(ptr, chunk, item_size);
4435 item_size += sizeof(disk_key);
4436 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
4437 unlock_chunks(root);
4438
4439 return 0;
4440 }
4441
4442 /*
4443 * sort the devices in descending order by max_avail, total_avail
4444 */
4445 static int btrfs_cmp_device_info(const void *a, const void *b)
4446 {
4447 const struct btrfs_device_info *di_a = a;
4448 const struct btrfs_device_info *di_b = b;
4449
4450 if (di_a->max_avail > di_b->max_avail)
4451 return -1;
4452 if (di_a->max_avail < di_b->max_avail)
4453 return 1;
4454 if (di_a->total_avail > di_b->total_avail)
4455 return -1;
4456 if (di_a->total_avail < di_b->total_avail)
4457 return 1;
4458 return 0;
4459 }
4460
4461 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
4462 {
4463 /* TODO allow them to set a preferred stripe size */
4464 return 64 * 1024;
4465 }
4466
4467 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
4468 {
4469 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
4470 return;
4471
4472 btrfs_set_fs_incompat(info, RAID56);
4473 }
4474
4475 #define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \
4476 - sizeof(struct btrfs_item) \
4477 - sizeof(struct btrfs_chunk)) \
4478 / sizeof(struct btrfs_stripe) + 1)
4479
4480 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
4481 - 2 * sizeof(struct btrfs_disk_key) \
4482 - 2 * sizeof(struct btrfs_chunk)) \
4483 / sizeof(struct btrfs_stripe) + 1)
4484
4485 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4486 struct btrfs_root *extent_root, u64 start,
4487 u64 type)
4488 {
4489 struct btrfs_fs_info *info = extent_root->fs_info;
4490 struct btrfs_fs_devices *fs_devices = info->fs_devices;
4491 struct list_head *cur;
4492 struct map_lookup *map = NULL;
4493 struct extent_map_tree *em_tree;
4494 struct extent_map *em;
4495 struct btrfs_device_info *devices_info = NULL;
4496 u64 total_avail;
4497 int num_stripes; /* total number of stripes to allocate */
4498 int data_stripes; /* number of stripes that count for
4499 block group size */
4500 int sub_stripes; /* sub_stripes info for map */
4501 int dev_stripes; /* stripes per dev */
4502 int devs_max; /* max devs to use */
4503 int devs_min; /* min devs needed */
4504 int devs_increment; /* ndevs has to be a multiple of this */
4505 int ncopies; /* how many copies to data has */
4506 int ret;
4507 u64 max_stripe_size;
4508 u64 max_chunk_size;
4509 u64 stripe_size;
4510 u64 num_bytes;
4511 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
4512 int ndevs;
4513 int i;
4514 int j;
4515 int index;
4516
4517 BUG_ON(!alloc_profile_is_valid(type, 0));
4518
4519 if (list_empty(&fs_devices->alloc_list))
4520 return -ENOSPC;
4521
4522 index = __get_raid_index(type);
4523
4524 sub_stripes = btrfs_raid_array[index].sub_stripes;
4525 dev_stripes = btrfs_raid_array[index].dev_stripes;
4526 devs_max = btrfs_raid_array[index].devs_max;
4527 devs_min = btrfs_raid_array[index].devs_min;
4528 devs_increment = btrfs_raid_array[index].devs_increment;
4529 ncopies = btrfs_raid_array[index].ncopies;
4530
4531 if (type & BTRFS_BLOCK_GROUP_DATA) {
4532 max_stripe_size = 1024 * 1024 * 1024;
4533 max_chunk_size = 10 * max_stripe_size;
4534 if (!devs_max)
4535 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4536 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
4537 /* for larger filesystems, use larger metadata chunks */
4538 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
4539 max_stripe_size = 1024 * 1024 * 1024;
4540 else
4541 max_stripe_size = 256 * 1024 * 1024;
4542 max_chunk_size = max_stripe_size;
4543 if (!devs_max)
4544 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4545 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
4546 max_stripe_size = 32 * 1024 * 1024;
4547 max_chunk_size = 2 * max_stripe_size;
4548 if (!devs_max)
4549 devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
4550 } else {
4551 btrfs_err(info, "invalid chunk type 0x%llx requested",
4552 type);
4553 BUG_ON(1);
4554 }
4555
4556 /* we don't want a chunk larger than 10% of writeable space */
4557 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
4558 max_chunk_size);
4559
4560 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
4561 GFP_NOFS);
4562 if (!devices_info)
4563 return -ENOMEM;
4564
4565 cur = fs_devices->alloc_list.next;
4566
4567 /*
4568 * in the first pass through the devices list, we gather information
4569 * about the available holes on each device.
4570 */
4571 ndevs = 0;
4572 while (cur != &fs_devices->alloc_list) {
4573 struct btrfs_device *device;
4574 u64 max_avail;
4575 u64 dev_offset;
4576
4577 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
4578
4579 cur = cur->next;
4580
4581 if (!device->writeable) {
4582 WARN(1, KERN_ERR
4583 "BTRFS: read-only device in alloc_list\n");
4584 continue;
4585 }
4586
4587 if (!device->in_fs_metadata ||
4588 device->is_tgtdev_for_dev_replace)
4589 continue;
4590
4591 if (device->total_bytes > device->bytes_used)
4592 total_avail = device->total_bytes - device->bytes_used;
4593 else
4594 total_avail = 0;
4595
4596 /* If there is no space on this device, skip it. */
4597 if (total_avail == 0)
4598 continue;
4599
4600 ret = find_free_dev_extent(trans, device,
4601 max_stripe_size * dev_stripes,
4602 &dev_offset, &max_avail);
4603 if (ret && ret != -ENOSPC)
4604 goto error;
4605
4606 if (ret == 0)
4607 max_avail = max_stripe_size * dev_stripes;
4608
4609 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
4610 continue;
4611
4612 if (ndevs == fs_devices->rw_devices) {
4613 WARN(1, "%s: found more than %llu devices\n",
4614 __func__, fs_devices->rw_devices);
4615 break;
4616 }
4617 devices_info[ndevs].dev_offset = dev_offset;
4618 devices_info[ndevs].max_avail = max_avail;
4619 devices_info[ndevs].total_avail = total_avail;
4620 devices_info[ndevs].dev = device;
4621 ++ndevs;
4622 }
4623
4624 /*
4625 * now sort the devices by hole size / available space
4626 */
4627 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
4628 btrfs_cmp_device_info, NULL);
4629
4630 /* round down to number of usable stripes */
4631 ndevs -= ndevs % devs_increment;
4632
4633 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
4634 ret = -ENOSPC;
4635 goto error;
4636 }
4637
4638 if (devs_max && ndevs > devs_max)
4639 ndevs = devs_max;
4640 /*
4641 * the primary goal is to maximize the number of stripes, so use as many
4642 * devices as possible, even if the stripes are not maximum sized.
4643 */
4644 stripe_size = devices_info[ndevs-1].max_avail;
4645 num_stripes = ndevs * dev_stripes;
4646
4647 /*
4648 * this will have to be fixed for RAID1 and RAID10 over
4649 * more drives
4650 */
4651 data_stripes = num_stripes / ncopies;
4652
4653 if (type & BTRFS_BLOCK_GROUP_RAID5) {
4654 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
4655 btrfs_super_stripesize(info->super_copy));
4656 data_stripes = num_stripes - 1;
4657 }
4658 if (type & BTRFS_BLOCK_GROUP_RAID6) {
4659 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
4660 btrfs_super_stripesize(info->super_copy));
4661 data_stripes = num_stripes - 2;
4662 }
4663
4664 /*
4665 * Use the number of data stripes to figure out how big this chunk
4666 * is really going to be in terms of logical address space,
4667 * and compare that answer with the max chunk size
4668 */
4669 if (stripe_size * data_stripes > max_chunk_size) {
4670 u64 mask = (1ULL << 24) - 1;
4671
4672 stripe_size = div_u64(max_chunk_size, data_stripes);
4673
4674 /* bump the answer up to a 16MB boundary */
4675 stripe_size = (stripe_size + mask) & ~mask;
4676
4677 /* but don't go higher than the limits we found
4678 * while searching for free extents
4679 */
4680 if (stripe_size > devices_info[ndevs-1].max_avail)
4681 stripe_size = devices_info[ndevs-1].max_avail;
4682 }
4683
4684 stripe_size = div_u64(stripe_size, dev_stripes);
4685
4686 /* align to BTRFS_STRIPE_LEN */
4687 stripe_size = div_u64(stripe_size, raid_stripe_len);
4688 stripe_size *= raid_stripe_len;
4689
4690 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4691 if (!map) {
4692 ret = -ENOMEM;
4693 goto error;
4694 }
4695 map->num_stripes = num_stripes;
4696
4697 for (i = 0; i < ndevs; ++i) {
4698 for (j = 0; j < dev_stripes; ++j) {
4699 int s = i * dev_stripes + j;
4700 map->stripes[s].dev = devices_info[i].dev;
4701 map->stripes[s].physical = devices_info[i].dev_offset +
4702 j * stripe_size;
4703 }
4704 }
4705 map->sector_size = extent_root->sectorsize;
4706 map->stripe_len = raid_stripe_len;
4707 map->io_align = raid_stripe_len;
4708 map->io_width = raid_stripe_len;
4709 map->type = type;
4710 map->sub_stripes = sub_stripes;
4711
4712 num_bytes = stripe_size * data_stripes;
4713
4714 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
4715
4716 em = alloc_extent_map();
4717 if (!em) {
4718 kfree(map);
4719 ret = -ENOMEM;
4720 goto error;
4721 }
4722 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
4723 em->bdev = (struct block_device *)map;
4724 em->start = start;
4725 em->len = num_bytes;
4726 em->block_start = 0;
4727 em->block_len = em->len;
4728 em->orig_block_len = stripe_size;
4729
4730 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4731 write_lock(&em_tree->lock);
4732 ret = add_extent_mapping(em_tree, em, 0);
4733 if (!ret) {
4734 list_add_tail(&em->list, &trans->transaction->pending_chunks);
4735 atomic_inc(&em->refs);
4736 }
4737 write_unlock(&em_tree->lock);
4738 if (ret) {
4739 free_extent_map(em);
4740 goto error;
4741 }
4742
4743 ret = btrfs_make_block_group(trans, extent_root, 0, type,
4744 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4745 start, num_bytes);
4746 if (ret)
4747 goto error_del_extent;
4748
4749 for (i = 0; i < map->num_stripes; i++) {
4750 num_bytes = map->stripes[i].dev->bytes_used + stripe_size;
4751 btrfs_device_set_bytes_used(map->stripes[i].dev, num_bytes);
4752 }
4753
4754 spin_lock(&extent_root->fs_info->free_chunk_lock);
4755 extent_root->fs_info->free_chunk_space -= (stripe_size *
4756 map->num_stripes);
4757 spin_unlock(&extent_root->fs_info->free_chunk_lock);
4758
4759 free_extent_map(em);
4760 check_raid56_incompat_flag(extent_root->fs_info, type);
4761
4762 kfree(devices_info);
4763 return 0;
4764
4765 error_del_extent:
4766 write_lock(&em_tree->lock);
4767 remove_extent_mapping(em_tree, em);
4768 write_unlock(&em_tree->lock);
4769
4770 /* One for our allocation */
4771 free_extent_map(em);
4772 /* One for the tree reference */
4773 free_extent_map(em);
4774 /* One for the pending_chunks list reference */
4775 free_extent_map(em);
4776 error:
4777 kfree(devices_info);
4778 return ret;
4779 }
4780
4781 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
4782 struct btrfs_root *extent_root,
4783 u64 chunk_offset, u64 chunk_size)
4784 {
4785 struct btrfs_key key;
4786 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
4787 struct btrfs_device *device;
4788 struct btrfs_chunk *chunk;
4789 struct btrfs_stripe *stripe;
4790 struct extent_map_tree *em_tree;
4791 struct extent_map *em;
4792 struct map_lookup *map;
4793 size_t item_size;
4794 u64 dev_offset;
4795 u64 stripe_size;
4796 int i = 0;
4797 int ret;
4798
4799 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4800 read_lock(&em_tree->lock);
4801 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
4802 read_unlock(&em_tree->lock);
4803
4804 if (!em) {
4805 btrfs_crit(extent_root->fs_info, "unable to find logical "
4806 "%Lu len %Lu", chunk_offset, chunk_size);
4807 return -EINVAL;
4808 }
4809
4810 if (em->start != chunk_offset || em->len != chunk_size) {
4811 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted"
4812 " %Lu-%Lu, found %Lu-%Lu", chunk_offset,
4813 chunk_size, em->start, em->len);
4814 free_extent_map(em);
4815 return -EINVAL;
4816 }
4817
4818 map = (struct map_lookup *)em->bdev;
4819 item_size = btrfs_chunk_item_size(map->num_stripes);
4820 stripe_size = em->orig_block_len;
4821
4822 chunk = kzalloc(item_size, GFP_NOFS);
4823 if (!chunk) {
4824 ret = -ENOMEM;
4825 goto out;
4826 }
4827
4828 for (i = 0; i < map->num_stripes; i++) {
4829 device = map->stripes[i].dev;
4830 dev_offset = map->stripes[i].physical;
4831
4832 ret = btrfs_update_device(trans, device);
4833 if (ret)
4834 goto out;
4835 ret = btrfs_alloc_dev_extent(trans, device,
4836 chunk_root->root_key.objectid,
4837 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4838 chunk_offset, dev_offset,
4839 stripe_size);
4840 if (ret)
4841 goto out;
4842 }
4843
4844 stripe = &chunk->stripe;
4845 for (i = 0; i < map->num_stripes; i++) {
4846 device = map->stripes[i].dev;
4847 dev_offset = map->stripes[i].physical;
4848
4849 btrfs_set_stack_stripe_devid(stripe, device->devid);
4850 btrfs_set_stack_stripe_offset(stripe, dev_offset);
4851 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
4852 stripe++;
4853 }
4854
4855 btrfs_set_stack_chunk_length(chunk, chunk_size);
4856 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
4857 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
4858 btrfs_set_stack_chunk_type(chunk, map->type);
4859 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
4860 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
4861 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
4862 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
4863 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
4864
4865 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4866 key.type = BTRFS_CHUNK_ITEM_KEY;
4867 key.offset = chunk_offset;
4868
4869 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
4870 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
4871 /*
4872 * TODO: Cleanup of inserted chunk root in case of
4873 * failure.
4874 */
4875 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
4876 item_size);
4877 }
4878
4879 out:
4880 kfree(chunk);
4881 free_extent_map(em);
4882 return ret;
4883 }
4884
4885 /*
4886 * Chunk allocation falls into two parts. The first part does works
4887 * that make the new allocated chunk useable, but not do any operation
4888 * that modifies the chunk tree. The second part does the works that
4889 * require modifying the chunk tree. This division is important for the
4890 * bootstrap process of adding storage to a seed btrfs.
4891 */
4892 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4893 struct btrfs_root *extent_root, u64 type)
4894 {
4895 u64 chunk_offset;
4896
4897 ASSERT(mutex_is_locked(&extent_root->fs_info->chunk_mutex));
4898 chunk_offset = find_next_chunk(extent_root->fs_info);
4899 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type);
4900 }
4901
4902 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
4903 struct btrfs_root *root,
4904 struct btrfs_device *device)
4905 {
4906 u64 chunk_offset;
4907 u64 sys_chunk_offset;
4908 u64 alloc_profile;
4909 struct btrfs_fs_info *fs_info = root->fs_info;
4910 struct btrfs_root *extent_root = fs_info->extent_root;
4911 int ret;
4912
4913 chunk_offset = find_next_chunk(fs_info);
4914 alloc_profile = btrfs_get_alloc_profile(extent_root, 0);
4915 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset,
4916 alloc_profile);
4917 if (ret)
4918 return ret;
4919
4920 sys_chunk_offset = find_next_chunk(root->fs_info);
4921 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
4922 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset,
4923 alloc_profile);
4924 return ret;
4925 }
4926
4927 static inline int btrfs_chunk_max_errors(struct map_lookup *map)
4928 {
4929 int max_errors;
4930
4931 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
4932 BTRFS_BLOCK_GROUP_RAID10 |
4933 BTRFS_BLOCK_GROUP_RAID5 |
4934 BTRFS_BLOCK_GROUP_DUP)) {
4935 max_errors = 1;
4936 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
4937 max_errors = 2;
4938 } else {
4939 max_errors = 0;
4940 }
4941
4942 return max_errors;
4943 }
4944
4945 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
4946 {
4947 struct extent_map *em;
4948 struct map_lookup *map;
4949 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4950 int readonly = 0;
4951 int miss_ndevs = 0;
4952 int i;
4953
4954 read_lock(&map_tree->map_tree.lock);
4955 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
4956 read_unlock(&map_tree->map_tree.lock);
4957 if (!em)
4958 return 1;
4959
4960 map = (struct map_lookup *)em->bdev;
4961 for (i = 0; i < map->num_stripes; i++) {
4962 if (map->stripes[i].dev->missing) {
4963 miss_ndevs++;
4964 continue;
4965 }
4966
4967 if (!map->stripes[i].dev->writeable) {
4968 readonly = 1;
4969 goto end;
4970 }
4971 }
4972
4973 /*
4974 * If the number of missing devices is larger than max errors,
4975 * we can not write the data into that chunk successfully, so
4976 * set it readonly.
4977 */
4978 if (miss_ndevs > btrfs_chunk_max_errors(map))
4979 readonly = 1;
4980 end:
4981 free_extent_map(em);
4982 return readonly;
4983 }
4984
4985 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
4986 {
4987 extent_map_tree_init(&tree->map_tree);
4988 }
4989
4990 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
4991 {
4992 struct extent_map *em;
4993
4994 while (1) {
4995 write_lock(&tree->map_tree.lock);
4996 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
4997 if (em)
4998 remove_extent_mapping(&tree->map_tree, em);
4999 write_unlock(&tree->map_tree.lock);
5000 if (!em)
5001 break;
5002 /* once for us */
5003 free_extent_map(em);
5004 /* once for the tree */
5005 free_extent_map(em);
5006 }
5007 }
5008
5009 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
5010 {
5011 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
5012 struct extent_map *em;
5013 struct map_lookup *map;
5014 struct extent_map_tree *em_tree = &map_tree->map_tree;
5015 int ret;
5016
5017 read_lock(&em_tree->lock);
5018 em = lookup_extent_mapping(em_tree, logical, len);
5019 read_unlock(&em_tree->lock);
5020
5021 /*
5022 * We could return errors for these cases, but that could get ugly and
5023 * we'd probably do the same thing which is just not do anything else
5024 * and exit, so return 1 so the callers don't try to use other copies.
5025 */
5026 if (!em) {
5027 btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
5028 logical+len);
5029 return 1;
5030 }
5031
5032 if (em->start > logical || em->start + em->len < logical) {
5033 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got "
5034 "%Lu-%Lu", logical, logical+len, em->start,
5035 em->start + em->len);
5036 free_extent_map(em);
5037 return 1;
5038 }
5039
5040 map = (struct map_lookup *)em->bdev;
5041 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
5042 ret = map->num_stripes;
5043 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5044 ret = map->sub_stripes;
5045 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
5046 ret = 2;
5047 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5048 ret = 3;
5049 else
5050 ret = 1;
5051 free_extent_map(em);
5052
5053 btrfs_dev_replace_lock(&fs_info->dev_replace);
5054 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
5055 ret++;
5056 btrfs_dev_replace_unlock(&fs_info->dev_replace);
5057
5058 return ret;
5059 }
5060
5061 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
5062 struct btrfs_mapping_tree *map_tree,
5063 u64 logical)
5064 {
5065 struct extent_map *em;
5066 struct map_lookup *map;
5067 struct extent_map_tree *em_tree = &map_tree->map_tree;
5068 unsigned long len = root->sectorsize;
5069
5070 read_lock(&em_tree->lock);
5071 em = lookup_extent_mapping(em_tree, logical, len);
5072 read_unlock(&em_tree->lock);
5073 BUG_ON(!em);
5074
5075 BUG_ON(em->start > logical || em->start + em->len < logical);
5076 map = (struct map_lookup *)em->bdev;
5077 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
5078 len = map->stripe_len * nr_data_stripes(map);
5079 free_extent_map(em);
5080 return len;
5081 }
5082
5083 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
5084 u64 logical, u64 len, int mirror_num)
5085 {
5086 struct extent_map *em;
5087 struct map_lookup *map;
5088 struct extent_map_tree *em_tree = &map_tree->map_tree;
5089 int ret = 0;
5090
5091 read_lock(&em_tree->lock);
5092 em = lookup_extent_mapping(em_tree, logical, len);
5093 read_unlock(&em_tree->lock);
5094 BUG_ON(!em);
5095
5096 BUG_ON(em->start > logical || em->start + em->len < logical);
5097 map = (struct map_lookup *)em->bdev;
5098 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
5099 ret = 1;
5100 free_extent_map(em);
5101 return ret;
5102 }
5103
5104 static int find_live_mirror(struct btrfs_fs_info *fs_info,
5105 struct map_lookup *map, int first, int num,
5106 int optimal, int dev_replace_is_ongoing)
5107 {
5108 int i;
5109 int tolerance;
5110 struct btrfs_device *srcdev;
5111
5112 if (dev_replace_is_ongoing &&
5113 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
5114 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
5115 srcdev = fs_info->dev_replace.srcdev;
5116 else
5117 srcdev = NULL;
5118
5119 /*
5120 * try to avoid the drive that is the source drive for a
5121 * dev-replace procedure, only choose it if no other non-missing
5122 * mirror is available
5123 */
5124 for (tolerance = 0; tolerance < 2; tolerance++) {
5125 if (map->stripes[optimal].dev->bdev &&
5126 (tolerance || map->stripes[optimal].dev != srcdev))
5127 return optimal;
5128 for (i = first; i < first + num; i++) {
5129 if (map->stripes[i].dev->bdev &&
5130 (tolerance || map->stripes[i].dev != srcdev))
5131 return i;
5132 }
5133 }
5134
5135 /* we couldn't find one that doesn't fail. Just return something
5136 * and the io error handling code will clean up eventually
5137 */
5138 return optimal;
5139 }
5140
5141 static inline int parity_smaller(u64 a, u64 b)
5142 {
5143 return a > b;
5144 }
5145
5146 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
5147 static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes)
5148 {
5149 struct btrfs_bio_stripe s;
5150 int i;
5151 u64 l;
5152 int again = 1;
5153
5154 while (again) {
5155 again = 0;
5156 for (i = 0; i < num_stripes - 1; i++) {
5157 if (parity_smaller(bbio->raid_map[i],
5158 bbio->raid_map[i+1])) {
5159 s = bbio->stripes[i];
5160 l = bbio->raid_map[i];
5161 bbio->stripes[i] = bbio->stripes[i+1];
5162 bbio->raid_map[i] = bbio->raid_map[i+1];
5163 bbio->stripes[i+1] = s;
5164 bbio->raid_map[i+1] = l;
5165
5166 again = 1;
5167 }
5168 }
5169 }
5170 }
5171
5172 static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
5173 {
5174 struct btrfs_bio *bbio = kzalloc(
5175 /* the size of the btrfs_bio */
5176 sizeof(struct btrfs_bio) +
5177 /* plus the variable array for the stripes */
5178 sizeof(struct btrfs_bio_stripe) * (total_stripes) +
5179 /* plus the variable array for the tgt dev */
5180 sizeof(int) * (real_stripes) +
5181 /*
5182 * plus the raid_map, which includes both the tgt dev
5183 * and the stripes
5184 */
5185 sizeof(u64) * (total_stripes),
5186 GFP_NOFS|__GFP_NOFAIL);
5187
5188 atomic_set(&bbio->error, 0);
5189 atomic_set(&bbio->refs, 1);
5190
5191 return bbio;
5192 }
5193
5194 void btrfs_get_bbio(struct btrfs_bio *bbio)
5195 {
5196 WARN_ON(!atomic_read(&bbio->refs));
5197 atomic_inc(&bbio->refs);
5198 }
5199
5200 void btrfs_put_bbio(struct btrfs_bio *bbio)
5201 {
5202 if (!bbio)
5203 return;
5204 if (atomic_dec_and_test(&bbio->refs))
5205 kfree(bbio);
5206 }
5207
5208 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5209 u64 logical, u64 *length,
5210 struct btrfs_bio **bbio_ret,
5211 int mirror_num, int need_raid_map)
5212 {
5213 struct extent_map *em;
5214 struct map_lookup *map;
5215 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
5216 struct extent_map_tree *em_tree = &map_tree->map_tree;
5217 u64 offset;
5218 u64 stripe_offset;
5219 u64 stripe_end_offset;
5220 u64 stripe_nr;
5221 u64 stripe_nr_orig;
5222 u64 stripe_nr_end;
5223 u64 stripe_len;
5224 u32 stripe_index;
5225 int i;
5226 int ret = 0;
5227 int num_stripes;
5228 int max_errors = 0;
5229 int tgtdev_indexes = 0;
5230 struct btrfs_bio *bbio = NULL;
5231 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
5232 int dev_replace_is_ongoing = 0;
5233 int num_alloc_stripes;
5234 int patch_the_first_stripe_for_dev_replace = 0;
5235 u64 physical_to_patch_in_first_stripe = 0;
5236 u64 raid56_full_stripe_start = (u64)-1;
5237
5238 read_lock(&em_tree->lock);
5239 em = lookup_extent_mapping(em_tree, logical, *length);
5240 read_unlock(&em_tree->lock);
5241
5242 if (!em) {
5243 btrfs_crit(fs_info, "unable to find logical %llu len %llu",
5244 logical, *length);
5245 return -EINVAL;
5246 }
5247
5248 if (em->start > logical || em->start + em->len < logical) {
5249 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, "
5250 "found %Lu-%Lu", logical, em->start,
5251 em->start + em->len);
5252 free_extent_map(em);
5253 return -EINVAL;
5254 }
5255
5256 map = (struct map_lookup *)em->bdev;
5257 offset = logical - em->start;
5258
5259 stripe_len = map->stripe_len;
5260 stripe_nr = offset;
5261 /*
5262 * stripe_nr counts the total number of stripes we have to stride
5263 * to get to this block
5264 */
5265 stripe_nr = div64_u64(stripe_nr, stripe_len);
5266
5267 stripe_offset = stripe_nr * stripe_len;
5268 BUG_ON(offset < stripe_offset);
5269
5270 /* stripe_offset is the offset of this block in its stripe*/
5271 stripe_offset = offset - stripe_offset;
5272
5273 /* if we're here for raid56, we need to know the stripe aligned start */
5274 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5275 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
5276 raid56_full_stripe_start = offset;
5277
5278 /* allow a write of a full stripe, but make sure we don't
5279 * allow straddling of stripes
5280 */
5281 raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
5282 full_stripe_len);
5283 raid56_full_stripe_start *= full_stripe_len;
5284 }
5285
5286 if (rw & REQ_DISCARD) {
5287 /* we don't discard raid56 yet */
5288 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5289 ret = -EOPNOTSUPP;
5290 goto out;
5291 }
5292 *length = min_t(u64, em->len - offset, *length);
5293 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
5294 u64 max_len;
5295 /* For writes to RAID[56], allow a full stripeset across all disks.
5296 For other RAID types and for RAID[56] reads, just allow a single
5297 stripe (on a single disk). */
5298 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
5299 (rw & REQ_WRITE)) {
5300 max_len = stripe_len * nr_data_stripes(map) -
5301 (offset - raid56_full_stripe_start);
5302 } else {
5303 /* we limit the length of each bio to what fits in a stripe */
5304 max_len = stripe_len - stripe_offset;
5305 }
5306 *length = min_t(u64, em->len - offset, max_len);
5307 } else {
5308 *length = em->len - offset;
5309 }
5310
5311 /* This is for when we're called from btrfs_merge_bio_hook() and all
5312 it cares about is the length */
5313 if (!bbio_ret)
5314 goto out;
5315
5316 btrfs_dev_replace_lock(dev_replace);
5317 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
5318 if (!dev_replace_is_ongoing)
5319 btrfs_dev_replace_unlock(dev_replace);
5320
5321 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
5322 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
5323 dev_replace->tgtdev != NULL) {
5324 /*
5325 * in dev-replace case, for repair case (that's the only
5326 * case where the mirror is selected explicitly when
5327 * calling btrfs_map_block), blocks left of the left cursor
5328 * can also be read from the target drive.
5329 * For REQ_GET_READ_MIRRORS, the target drive is added as
5330 * the last one to the array of stripes. For READ, it also
5331 * needs to be supported using the same mirror number.
5332 * If the requested block is not left of the left cursor,
5333 * EIO is returned. This can happen because btrfs_num_copies()
5334 * returns one more in the dev-replace case.
5335 */
5336 u64 tmp_length = *length;
5337 struct btrfs_bio *tmp_bbio = NULL;
5338 int tmp_num_stripes;
5339 u64 srcdev_devid = dev_replace->srcdev->devid;
5340 int index_srcdev = 0;
5341 int found = 0;
5342 u64 physical_of_found = 0;
5343
5344 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
5345 logical, &tmp_length, &tmp_bbio, 0, 0);
5346 if (ret) {
5347 WARN_ON(tmp_bbio != NULL);
5348 goto out;
5349 }
5350
5351 tmp_num_stripes = tmp_bbio->num_stripes;
5352 if (mirror_num > tmp_num_stripes) {
5353 /*
5354 * REQ_GET_READ_MIRRORS does not contain this
5355 * mirror, that means that the requested area
5356 * is not left of the left cursor
5357 */
5358 ret = -EIO;
5359 btrfs_put_bbio(tmp_bbio);
5360 goto out;
5361 }
5362
5363 /*
5364 * process the rest of the function using the mirror_num
5365 * of the source drive. Therefore look it up first.
5366 * At the end, patch the device pointer to the one of the
5367 * target drive.
5368 */
5369 for (i = 0; i < tmp_num_stripes; i++) {
5370 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) {
5371 /*
5372 * In case of DUP, in order to keep it
5373 * simple, only add the mirror with the
5374 * lowest physical address
5375 */
5376 if (found &&
5377 physical_of_found <=
5378 tmp_bbio->stripes[i].physical)
5379 continue;
5380 index_srcdev = i;
5381 found = 1;
5382 physical_of_found =
5383 tmp_bbio->stripes[i].physical;
5384 }
5385 }
5386
5387 if (found) {
5388 mirror_num = index_srcdev + 1;
5389 patch_the_first_stripe_for_dev_replace = 1;
5390 physical_to_patch_in_first_stripe = physical_of_found;
5391 } else {
5392 WARN_ON(1);
5393 ret = -EIO;
5394 btrfs_put_bbio(tmp_bbio);
5395 goto out;
5396 }
5397
5398 btrfs_put_bbio(tmp_bbio);
5399 } else if (mirror_num > map->num_stripes) {
5400 mirror_num = 0;
5401 }
5402
5403 num_stripes = 1;
5404 stripe_index = 0;
5405 stripe_nr_orig = stripe_nr;
5406 stripe_nr_end = ALIGN(offset + *length, map->stripe_len);
5407 stripe_nr_end = div_u64(stripe_nr_end, map->stripe_len);
5408 stripe_end_offset = stripe_nr_end * map->stripe_len -
5409 (offset + *length);
5410
5411 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5412 if (rw & REQ_DISCARD)
5413 num_stripes = min_t(u64, map->num_stripes,
5414 stripe_nr_end - stripe_nr_orig);
5415 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5416 &stripe_index);
5417 if (!(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)))
5418 mirror_num = 1;
5419 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
5420 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
5421 num_stripes = map->num_stripes;
5422 else if (mirror_num)
5423 stripe_index = mirror_num - 1;
5424 else {
5425 stripe_index = find_live_mirror(fs_info, map, 0,
5426 map->num_stripes,
5427 current->pid % map->num_stripes,
5428 dev_replace_is_ongoing);
5429 mirror_num = stripe_index + 1;
5430 }
5431
5432 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
5433 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
5434 num_stripes = map->num_stripes;
5435 } else if (mirror_num) {
5436 stripe_index = mirror_num - 1;
5437 } else {
5438 mirror_num = 1;
5439 }
5440
5441 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5442 u32 factor = map->num_stripes / map->sub_stripes;
5443
5444 stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
5445 stripe_index *= map->sub_stripes;
5446
5447 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5448 num_stripes = map->sub_stripes;
5449 else if (rw & REQ_DISCARD)
5450 num_stripes = min_t(u64, map->sub_stripes *
5451 (stripe_nr_end - stripe_nr_orig),
5452 map->num_stripes);
5453 else if (mirror_num)
5454 stripe_index += mirror_num - 1;
5455 else {
5456 int old_stripe_index = stripe_index;
5457 stripe_index = find_live_mirror(fs_info, map,
5458 stripe_index,
5459 map->sub_stripes, stripe_index +
5460 current->pid % map->sub_stripes,
5461 dev_replace_is_ongoing);
5462 mirror_num = stripe_index - old_stripe_index + 1;
5463 }
5464
5465 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5466 if (need_raid_map &&
5467 ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5468 mirror_num > 1)) {
5469 /* push stripe_nr back to the start of the full stripe */
5470 stripe_nr = div_u64(raid56_full_stripe_start,
5471 stripe_len * nr_data_stripes(map));
5472
5473 /* RAID[56] write or recovery. Return all stripes */
5474 num_stripes = map->num_stripes;
5475 max_errors = nr_parity_stripes(map);
5476
5477 *length = map->stripe_len;
5478 stripe_index = 0;
5479 stripe_offset = 0;
5480 } else {
5481 /*
5482 * Mirror #0 or #1 means the original data block.
5483 * Mirror #2 is RAID5 parity block.
5484 * Mirror #3 is RAID6 Q block.
5485 */
5486 stripe_nr = div_u64_rem(stripe_nr,
5487 nr_data_stripes(map), &stripe_index);
5488 if (mirror_num > 1)
5489 stripe_index = nr_data_stripes(map) +
5490 mirror_num - 2;
5491
5492 /* We distribute the parity blocks across stripes */
5493 div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
5494 &stripe_index);
5495 if (!(rw & (REQ_WRITE | REQ_DISCARD |
5496 REQ_GET_READ_MIRRORS)) && mirror_num <= 1)
5497 mirror_num = 1;
5498 }
5499 } else {
5500 /*
5501 * after this, stripe_nr is the number of stripes on this
5502 * device we have to walk to find the data, and stripe_index is
5503 * the number of our device in the stripe array
5504 */
5505 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5506 &stripe_index);
5507 mirror_num = stripe_index + 1;
5508 }
5509 BUG_ON(stripe_index >= map->num_stripes);
5510
5511 num_alloc_stripes = num_stripes;
5512 if (dev_replace_is_ongoing) {
5513 if (rw & (REQ_WRITE | REQ_DISCARD))
5514 num_alloc_stripes <<= 1;
5515 if (rw & REQ_GET_READ_MIRRORS)
5516 num_alloc_stripes++;
5517 tgtdev_indexes = num_stripes;
5518 }
5519
5520 bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes);
5521 if (!bbio) {
5522 ret = -ENOMEM;
5523 goto out;
5524 }
5525 if (dev_replace_is_ongoing)
5526 bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes);
5527
5528 /* build raid_map */
5529 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
5530 need_raid_map && ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5531 mirror_num > 1)) {
5532 u64 tmp;
5533 unsigned rot;
5534
5535 bbio->raid_map = (u64 *)((void *)bbio->stripes +
5536 sizeof(struct btrfs_bio_stripe) *
5537 num_alloc_stripes +
5538 sizeof(int) * tgtdev_indexes);
5539
5540 /* Work out the disk rotation on this stripe-set */
5541 div_u64_rem(stripe_nr, num_stripes, &rot);
5542
5543 /* Fill in the logical address of each stripe */
5544 tmp = stripe_nr * nr_data_stripes(map);
5545 for (i = 0; i < nr_data_stripes(map); i++)
5546 bbio->raid_map[(i+rot) % num_stripes] =
5547 em->start + (tmp + i) * map->stripe_len;
5548
5549 bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
5550 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5551 bbio->raid_map[(i+rot+1) % num_stripes] =
5552 RAID6_Q_STRIPE;
5553 }
5554
5555 if (rw & REQ_DISCARD) {
5556 u32 factor = 0;
5557 u32 sub_stripes = 0;
5558 u64 stripes_per_dev = 0;
5559 u32 remaining_stripes = 0;
5560 u32 last_stripe = 0;
5561
5562 if (map->type &
5563 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
5564 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5565 sub_stripes = 1;
5566 else
5567 sub_stripes = map->sub_stripes;
5568
5569 factor = map->num_stripes / sub_stripes;
5570 stripes_per_dev = div_u64_rem(stripe_nr_end -
5571 stripe_nr_orig,
5572 factor,
5573 &remaining_stripes);
5574 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
5575 last_stripe *= sub_stripes;
5576 }
5577
5578 for (i = 0; i < num_stripes; i++) {
5579 bbio->stripes[i].physical =
5580 map->stripes[stripe_index].physical +
5581 stripe_offset + stripe_nr * map->stripe_len;
5582 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
5583
5584 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
5585 BTRFS_BLOCK_GROUP_RAID10)) {
5586 bbio->stripes[i].length = stripes_per_dev *
5587 map->stripe_len;
5588
5589 if (i / sub_stripes < remaining_stripes)
5590 bbio->stripes[i].length +=
5591 map->stripe_len;
5592
5593 /*
5594 * Special for the first stripe and
5595 * the last stripe:
5596 *
5597 * |-------|...|-------|
5598 * |----------|
5599 * off end_off
5600 */
5601 if (i < sub_stripes)
5602 bbio->stripes[i].length -=
5603 stripe_offset;
5604
5605 if (stripe_index >= last_stripe &&
5606 stripe_index <= (last_stripe +
5607 sub_stripes - 1))
5608 bbio->stripes[i].length -=
5609 stripe_end_offset;
5610
5611 if (i == sub_stripes - 1)
5612 stripe_offset = 0;
5613 } else
5614 bbio->stripes[i].length = *length;
5615
5616 stripe_index++;
5617 if (stripe_index == map->num_stripes) {
5618 /* This could only happen for RAID0/10 */
5619 stripe_index = 0;
5620 stripe_nr++;
5621 }
5622 }
5623 } else {
5624 for (i = 0; i < num_stripes; i++) {
5625 bbio->stripes[i].physical =
5626 map->stripes[stripe_index].physical +
5627 stripe_offset +
5628 stripe_nr * map->stripe_len;
5629 bbio->stripes[i].dev =
5630 map->stripes[stripe_index].dev;
5631 stripe_index++;
5632 }
5633 }
5634
5635 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5636 max_errors = btrfs_chunk_max_errors(map);
5637
5638 if (bbio->raid_map)
5639 sort_parity_stripes(bbio, num_stripes);
5640
5641 tgtdev_indexes = 0;
5642 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
5643 dev_replace->tgtdev != NULL) {
5644 int index_where_to_add;
5645 u64 srcdev_devid = dev_replace->srcdev->devid;
5646
5647 /*
5648 * duplicate the write operations while the dev replace
5649 * procedure is running. Since the copying of the old disk
5650 * to the new disk takes place at run time while the
5651 * filesystem is mounted writable, the regular write
5652 * operations to the old disk have to be duplicated to go
5653 * to the new disk as well.
5654 * Note that device->missing is handled by the caller, and
5655 * that the write to the old disk is already set up in the
5656 * stripes array.
5657 */
5658 index_where_to_add = num_stripes;
5659 for (i = 0; i < num_stripes; i++) {
5660 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5661 /* write to new disk, too */
5662 struct btrfs_bio_stripe *new =
5663 bbio->stripes + index_where_to_add;
5664 struct btrfs_bio_stripe *old =
5665 bbio->stripes + i;
5666
5667 new->physical = old->physical;
5668 new->length = old->length;
5669 new->dev = dev_replace->tgtdev;
5670 bbio->tgtdev_map[i] = index_where_to_add;
5671 index_where_to_add++;
5672 max_errors++;
5673 tgtdev_indexes++;
5674 }
5675 }
5676 num_stripes = index_where_to_add;
5677 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
5678 dev_replace->tgtdev != NULL) {
5679 u64 srcdev_devid = dev_replace->srcdev->devid;
5680 int index_srcdev = 0;
5681 int found = 0;
5682 u64 physical_of_found = 0;
5683
5684 /*
5685 * During the dev-replace procedure, the target drive can
5686 * also be used to read data in case it is needed to repair
5687 * a corrupt block elsewhere. This is possible if the
5688 * requested area is left of the left cursor. In this area,
5689 * the target drive is a full copy of the source drive.
5690 */
5691 for (i = 0; i < num_stripes; i++) {
5692 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5693 /*
5694 * In case of DUP, in order to keep it
5695 * simple, only add the mirror with the
5696 * lowest physical address
5697 */
5698 if (found &&
5699 physical_of_found <=
5700 bbio->stripes[i].physical)
5701 continue;
5702 index_srcdev = i;
5703 found = 1;
5704 physical_of_found = bbio->stripes[i].physical;
5705 }
5706 }
5707 if (found) {
5708 if (physical_of_found + map->stripe_len <=
5709 dev_replace->cursor_left) {
5710 struct btrfs_bio_stripe *tgtdev_stripe =
5711 bbio->stripes + num_stripes;
5712
5713 tgtdev_stripe->physical = physical_of_found;
5714 tgtdev_stripe->length =
5715 bbio->stripes[index_srcdev].length;
5716 tgtdev_stripe->dev = dev_replace->tgtdev;
5717 bbio->tgtdev_map[index_srcdev] = num_stripes;
5718
5719 tgtdev_indexes++;
5720 num_stripes++;
5721 }
5722 }
5723 }
5724
5725 *bbio_ret = bbio;
5726 bbio->map_type = map->type;
5727 bbio->num_stripes = num_stripes;
5728 bbio->max_errors = max_errors;
5729 bbio->mirror_num = mirror_num;
5730 bbio->num_tgtdevs = tgtdev_indexes;
5731
5732 /*
5733 * this is the case that REQ_READ && dev_replace_is_ongoing &&
5734 * mirror_num == num_stripes + 1 && dev_replace target drive is
5735 * available as a mirror
5736 */
5737 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
5738 WARN_ON(num_stripes > 1);
5739 bbio->stripes[0].dev = dev_replace->tgtdev;
5740 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
5741 bbio->mirror_num = map->num_stripes + 1;
5742 }
5743 out:
5744 if (dev_replace_is_ongoing)
5745 btrfs_dev_replace_unlock(dev_replace);
5746 free_extent_map(em);
5747 return ret;
5748 }
5749
5750 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5751 u64 logical, u64 *length,
5752 struct btrfs_bio **bbio_ret, int mirror_num)
5753 {
5754 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5755 mirror_num, 0);
5756 }
5757
5758 /* For Scrub/replace */
5759 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
5760 u64 logical, u64 *length,
5761 struct btrfs_bio **bbio_ret, int mirror_num,
5762 int need_raid_map)
5763 {
5764 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5765 mirror_num, need_raid_map);
5766 }
5767
5768 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
5769 u64 chunk_start, u64 physical, u64 devid,
5770 u64 **logical, int *naddrs, int *stripe_len)
5771 {
5772 struct extent_map_tree *em_tree = &map_tree->map_tree;
5773 struct extent_map *em;
5774 struct map_lookup *map;
5775 u64 *buf;
5776 u64 bytenr;
5777 u64 length;
5778 u64 stripe_nr;
5779 u64 rmap_len;
5780 int i, j, nr = 0;
5781
5782 read_lock(&em_tree->lock);
5783 em = lookup_extent_mapping(em_tree, chunk_start, 1);
5784 read_unlock(&em_tree->lock);
5785
5786 if (!em) {
5787 printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
5788 chunk_start);
5789 return -EIO;
5790 }
5791
5792 if (em->start != chunk_start) {
5793 printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
5794 em->start, chunk_start);
5795 free_extent_map(em);
5796 return -EIO;
5797 }
5798 map = (struct map_lookup *)em->bdev;
5799
5800 length = em->len;
5801 rmap_len = map->stripe_len;
5802
5803 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5804 length = div_u64(length, map->num_stripes / map->sub_stripes);
5805 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5806 length = div_u64(length, map->num_stripes);
5807 else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5808 length = div_u64(length, nr_data_stripes(map));
5809 rmap_len = map->stripe_len * nr_data_stripes(map);
5810 }
5811
5812 buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
5813 BUG_ON(!buf); /* -ENOMEM */
5814
5815 for (i = 0; i < map->num_stripes; i++) {
5816 if (devid && map->stripes[i].dev->devid != devid)
5817 continue;
5818 if (map->stripes[i].physical > physical ||
5819 map->stripes[i].physical + length <= physical)
5820 continue;
5821
5822 stripe_nr = physical - map->stripes[i].physical;
5823 stripe_nr = div_u64(stripe_nr, map->stripe_len);
5824
5825 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5826 stripe_nr = stripe_nr * map->num_stripes + i;
5827 stripe_nr = div_u64(stripe_nr, map->sub_stripes);
5828 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5829 stripe_nr = stripe_nr * map->num_stripes + i;
5830 } /* else if RAID[56], multiply by nr_data_stripes().
5831 * Alternatively, just use rmap_len below instead of
5832 * map->stripe_len */
5833
5834 bytenr = chunk_start + stripe_nr * rmap_len;
5835 WARN_ON(nr >= map->num_stripes);
5836 for (j = 0; j < nr; j++) {
5837 if (buf[j] == bytenr)
5838 break;
5839 }
5840 if (j == nr) {
5841 WARN_ON(nr >= map->num_stripes);
5842 buf[nr++] = bytenr;
5843 }
5844 }
5845
5846 *logical = buf;
5847 *naddrs = nr;
5848 *stripe_len = rmap_len;
5849
5850 free_extent_map(em);
5851 return 0;
5852 }
5853
5854 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio)
5855 {
5856 bio->bi_private = bbio->private;
5857 bio->bi_end_io = bbio->end_io;
5858 bio_endio(bio);
5859
5860 btrfs_put_bbio(bbio);
5861 }
5862
5863 static void btrfs_end_bio(struct bio *bio)
5864 {
5865 struct btrfs_bio *bbio = bio->bi_private;
5866 int is_orig_bio = 0;
5867
5868 if (bio->bi_error) {
5869 atomic_inc(&bbio->error);
5870 if (bio->bi_error == -EIO || bio->bi_error == -EREMOTEIO) {
5871 unsigned int stripe_index =
5872 btrfs_io_bio(bio)->stripe_index;
5873 struct btrfs_device *dev;
5874
5875 BUG_ON(stripe_index >= bbio->num_stripes);
5876 dev = bbio->stripes[stripe_index].dev;
5877 if (dev->bdev) {
5878 if (bio->bi_rw & WRITE)
5879 btrfs_dev_stat_inc(dev,
5880 BTRFS_DEV_STAT_WRITE_ERRS);
5881 else
5882 btrfs_dev_stat_inc(dev,
5883 BTRFS_DEV_STAT_READ_ERRS);
5884 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
5885 btrfs_dev_stat_inc(dev,
5886 BTRFS_DEV_STAT_FLUSH_ERRS);
5887 btrfs_dev_stat_print_on_error(dev);
5888 }
5889 }
5890 }
5891
5892 if (bio == bbio->orig_bio)
5893 is_orig_bio = 1;
5894
5895 btrfs_bio_counter_dec(bbio->fs_info);
5896
5897 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5898 if (!is_orig_bio) {
5899 bio_put(bio);
5900 bio = bbio->orig_bio;
5901 }
5902
5903 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5904 /* only send an error to the higher layers if it is
5905 * beyond the tolerance of the btrfs bio
5906 */
5907 if (atomic_read(&bbio->error) > bbio->max_errors) {
5908 bio->bi_error = -EIO;
5909 } else {
5910 /*
5911 * this bio is actually up to date, we didn't
5912 * go over the max number of errors
5913 */
5914 bio->bi_error = 0;
5915 }
5916
5917 btrfs_end_bbio(bbio, bio);
5918 } else if (!is_orig_bio) {
5919 bio_put(bio);
5920 }
5921 }
5922
5923 /*
5924 * see run_scheduled_bios for a description of why bios are collected for
5925 * async submit.
5926 *
5927 * This will add one bio to the pending list for a device and make sure
5928 * the work struct is scheduled.
5929 */
5930 static noinline void btrfs_schedule_bio(struct btrfs_root *root,
5931 struct btrfs_device *device,
5932 int rw, struct bio *bio)
5933 {
5934 int should_queue = 1;
5935 struct btrfs_pending_bios *pending_bios;
5936
5937 if (device->missing || !device->bdev) {
5938 bio_io_error(bio);
5939 return;
5940 }
5941
5942 /* don't bother with additional async steps for reads, right now */
5943 if (!(rw & REQ_WRITE)) {
5944 bio_get(bio);
5945 btrfsic_submit_bio(rw, bio);
5946 bio_put(bio);
5947 return;
5948 }
5949
5950 /*
5951 * nr_async_bios allows us to reliably return congestion to the
5952 * higher layers. Otherwise, the async bio makes it appear we have
5953 * made progress against dirty pages when we've really just put it
5954 * on a queue for later
5955 */
5956 atomic_inc(&root->fs_info->nr_async_bios);
5957 WARN_ON(bio->bi_next);
5958 bio->bi_next = NULL;
5959 bio->bi_rw |= rw;
5960
5961 spin_lock(&device->io_lock);
5962 if (bio->bi_rw & REQ_SYNC)
5963 pending_bios = &device->pending_sync_bios;
5964 else
5965 pending_bios = &device->pending_bios;
5966
5967 if (pending_bios->tail)
5968 pending_bios->tail->bi_next = bio;
5969
5970 pending_bios->tail = bio;
5971 if (!pending_bios->head)
5972 pending_bios->head = bio;
5973 if (device->running_pending)
5974 should_queue = 0;
5975
5976 spin_unlock(&device->io_lock);
5977
5978 if (should_queue)
5979 btrfs_queue_work(root->fs_info->submit_workers,
5980 &device->work);
5981 }
5982
5983 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5984 struct bio *bio, u64 physical, int dev_nr,
5985 int rw, int async)
5986 {
5987 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
5988
5989 bio->bi_private = bbio;
5990 btrfs_io_bio(bio)->stripe_index = dev_nr;
5991 bio->bi_end_io = btrfs_end_bio;
5992 bio->bi_iter.bi_sector = physical >> 9;
5993 #ifdef DEBUG
5994 {
5995 struct rcu_string *name;
5996
5997 rcu_read_lock();
5998 name = rcu_dereference(dev->name);
5999 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
6000 "(%s id %llu), size=%u\n", rw,
6001 (u64)bio->bi_iter.bi_sector, (u_long)dev->bdev->bd_dev,
6002 name->str, dev->devid, bio->bi_iter.bi_size);
6003 rcu_read_unlock();
6004 }
6005 #endif
6006 bio->bi_bdev = dev->bdev;
6007
6008 btrfs_bio_counter_inc_noblocked(root->fs_info);
6009
6010 if (async)
6011 btrfs_schedule_bio(root, dev, rw, bio);
6012 else
6013 btrfsic_submit_bio(rw, bio);
6014 }
6015
6016 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
6017 {
6018 atomic_inc(&bbio->error);
6019 if (atomic_dec_and_test(&bbio->stripes_pending)) {
6020 /* Shoud be the original bio. */
6021 WARN_ON(bio != bbio->orig_bio);
6022
6023 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
6024 bio->bi_iter.bi_sector = logical >> 9;
6025 bio->bi_error = -EIO;
6026 btrfs_end_bbio(bbio, bio);
6027 }
6028 }
6029
6030 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
6031 int mirror_num, int async_submit)
6032 {
6033 struct btrfs_device *dev;
6034 struct bio *first_bio = bio;
6035 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
6036 u64 length = 0;
6037 u64 map_length;
6038 int ret;
6039 int dev_nr;
6040 int total_devs;
6041 struct btrfs_bio *bbio = NULL;
6042
6043 length = bio->bi_iter.bi_size;
6044 map_length = length;
6045
6046 btrfs_bio_counter_inc_blocked(root->fs_info);
6047 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
6048 mirror_num, 1);
6049 if (ret) {
6050 btrfs_bio_counter_dec(root->fs_info);
6051 return ret;
6052 }
6053
6054 total_devs = bbio->num_stripes;
6055 bbio->orig_bio = first_bio;
6056 bbio->private = first_bio->bi_private;
6057 bbio->end_io = first_bio->bi_end_io;
6058 bbio->fs_info = root->fs_info;
6059 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
6060
6061 if (bbio->raid_map) {
6062 /* In this case, map_length has been set to the length of
6063 a single stripe; not the whole write */
6064 if (rw & WRITE) {
6065 ret = raid56_parity_write(root, bio, bbio, map_length);
6066 } else {
6067 ret = raid56_parity_recover(root, bio, bbio, map_length,
6068 mirror_num, 1);
6069 }
6070
6071 btrfs_bio_counter_dec(root->fs_info);
6072 return ret;
6073 }
6074
6075 if (map_length < length) {
6076 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
6077 logical, length, map_length);
6078 BUG();
6079 }
6080
6081 for (dev_nr = 0; dev_nr < total_devs; dev_nr++) {
6082 dev = bbio->stripes[dev_nr].dev;
6083 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
6084 bbio_error(bbio, first_bio, logical);
6085 continue;
6086 }
6087
6088 if (dev_nr < total_devs - 1) {
6089 bio = btrfs_bio_clone(first_bio, GFP_NOFS);
6090 BUG_ON(!bio); /* -ENOMEM */
6091 } else
6092 bio = first_bio;
6093
6094 submit_stripe_bio(root, bbio, bio,
6095 bbio->stripes[dev_nr].physical, dev_nr, rw,
6096 async_submit);
6097 }
6098 btrfs_bio_counter_dec(root->fs_info);
6099 return 0;
6100 }
6101
6102 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
6103 u8 *uuid, u8 *fsid)
6104 {
6105 struct btrfs_device *device;
6106 struct btrfs_fs_devices *cur_devices;
6107
6108 cur_devices = fs_info->fs_devices;
6109 while (cur_devices) {
6110 if (!fsid ||
6111 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
6112 device = __find_device(&cur_devices->devices,
6113 devid, uuid);
6114 if (device)
6115 return device;
6116 }
6117 cur_devices = cur_devices->seed;
6118 }
6119 return NULL;
6120 }
6121
6122 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
6123 struct btrfs_fs_devices *fs_devices,
6124 u64 devid, u8 *dev_uuid)
6125 {
6126 struct btrfs_device *device;
6127
6128 device = btrfs_alloc_device(NULL, &devid, dev_uuid);
6129 if (IS_ERR(device))
6130 return NULL;
6131
6132 list_add(&device->dev_list, &fs_devices->devices);
6133 device->fs_devices = fs_devices;
6134 fs_devices->num_devices++;
6135
6136 device->missing = 1;
6137 fs_devices->missing_devices++;
6138
6139 return device;
6140 }
6141
6142 /**
6143 * btrfs_alloc_device - allocate struct btrfs_device
6144 * @fs_info: used only for generating a new devid, can be NULL if
6145 * devid is provided (i.e. @devid != NULL).
6146 * @devid: a pointer to devid for this device. If NULL a new devid
6147 * is generated.
6148 * @uuid: a pointer to UUID for this device. If NULL a new UUID
6149 * is generated.
6150 *
6151 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
6152 * on error. Returned struct is not linked onto any lists and can be
6153 * destroyed with kfree() right away.
6154 */
6155 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
6156 const u64 *devid,
6157 const u8 *uuid)
6158 {
6159 struct btrfs_device *dev;
6160 u64 tmp;
6161
6162 if (WARN_ON(!devid && !fs_info))
6163 return ERR_PTR(-EINVAL);
6164
6165 dev = __alloc_device();
6166 if (IS_ERR(dev))
6167 return dev;
6168
6169 if (devid)
6170 tmp = *devid;
6171 else {
6172 int ret;
6173
6174 ret = find_next_devid(fs_info, &tmp);
6175 if (ret) {
6176 kfree(dev);
6177 return ERR_PTR(ret);
6178 }
6179 }
6180 dev->devid = tmp;
6181
6182 if (uuid)
6183 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
6184 else
6185 generate_random_uuid(dev->uuid);
6186
6187 btrfs_init_work(&dev->work, btrfs_submit_helper,
6188 pending_bios_fn, NULL, NULL);
6189
6190 return dev;
6191 }
6192
6193 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
6194 struct extent_buffer *leaf,
6195 struct btrfs_chunk *chunk)
6196 {
6197 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
6198 struct map_lookup *map;
6199 struct extent_map *em;
6200 u64 logical;
6201 u64 length;
6202 u64 devid;
6203 u8 uuid[BTRFS_UUID_SIZE];
6204 int num_stripes;
6205 int ret;
6206 int i;
6207
6208 logical = key->offset;
6209 length = btrfs_chunk_length(leaf, chunk);
6210
6211 read_lock(&map_tree->map_tree.lock);
6212 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
6213 read_unlock(&map_tree->map_tree.lock);
6214
6215 /* already mapped? */
6216 if (em && em->start <= logical && em->start + em->len > logical) {
6217 free_extent_map(em);
6218 return 0;
6219 } else if (em) {
6220 free_extent_map(em);
6221 }
6222
6223 em = alloc_extent_map();
6224 if (!em)
6225 return -ENOMEM;
6226 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
6227 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
6228 if (!map) {
6229 free_extent_map(em);
6230 return -ENOMEM;
6231 }
6232
6233 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
6234 em->bdev = (struct block_device *)map;
6235 em->start = logical;
6236 em->len = length;
6237 em->orig_start = 0;
6238 em->block_start = 0;
6239 em->block_len = em->len;
6240
6241 map->num_stripes = num_stripes;
6242 map->io_width = btrfs_chunk_io_width(leaf, chunk);
6243 map->io_align = btrfs_chunk_io_align(leaf, chunk);
6244 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
6245 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6246 map->type = btrfs_chunk_type(leaf, chunk);
6247 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
6248 for (i = 0; i < num_stripes; i++) {
6249 map->stripes[i].physical =
6250 btrfs_stripe_offset_nr(leaf, chunk, i);
6251 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
6252 read_extent_buffer(leaf, uuid, (unsigned long)
6253 btrfs_stripe_dev_uuid_nr(chunk, i),
6254 BTRFS_UUID_SIZE);
6255 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
6256 uuid, NULL);
6257 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
6258 free_extent_map(em);
6259 return -EIO;
6260 }
6261 if (!map->stripes[i].dev) {
6262 map->stripes[i].dev =
6263 add_missing_dev(root, root->fs_info->fs_devices,
6264 devid, uuid);
6265 if (!map->stripes[i].dev) {
6266 free_extent_map(em);
6267 return -EIO;
6268 }
6269 btrfs_warn(root->fs_info, "devid %llu uuid %pU is missing",
6270 devid, uuid);
6271 }
6272 map->stripes[i].dev->in_fs_metadata = 1;
6273 }
6274
6275 write_lock(&map_tree->map_tree.lock);
6276 ret = add_extent_mapping(&map_tree->map_tree, em, 0);
6277 write_unlock(&map_tree->map_tree.lock);
6278 BUG_ON(ret); /* Tree corruption */
6279 free_extent_map(em);
6280
6281 return 0;
6282 }
6283
6284 static void fill_device_from_item(struct extent_buffer *leaf,
6285 struct btrfs_dev_item *dev_item,
6286 struct btrfs_device *device)
6287 {
6288 unsigned long ptr;
6289
6290 device->devid = btrfs_device_id(leaf, dev_item);
6291 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
6292 device->total_bytes = device->disk_total_bytes;
6293 device->commit_total_bytes = device->disk_total_bytes;
6294 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
6295 device->commit_bytes_used = device->bytes_used;
6296 device->type = btrfs_device_type(leaf, dev_item);
6297 device->io_align = btrfs_device_io_align(leaf, dev_item);
6298 device->io_width = btrfs_device_io_width(leaf, dev_item);
6299 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
6300 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
6301 device->is_tgtdev_for_dev_replace = 0;
6302
6303 ptr = btrfs_device_uuid(dev_item);
6304 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
6305 }
6306
6307 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_root *root,
6308 u8 *fsid)
6309 {
6310 struct btrfs_fs_devices *fs_devices;
6311 int ret;
6312
6313 BUG_ON(!mutex_is_locked(&uuid_mutex));
6314
6315 fs_devices = root->fs_info->fs_devices->seed;
6316 while (fs_devices) {
6317 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE))
6318 return fs_devices;
6319
6320 fs_devices = fs_devices->seed;
6321 }
6322
6323 fs_devices = find_fsid(fsid);
6324 if (!fs_devices) {
6325 if (!btrfs_test_opt(root, DEGRADED))
6326 return ERR_PTR(-ENOENT);
6327
6328 fs_devices = alloc_fs_devices(fsid);
6329 if (IS_ERR(fs_devices))
6330 return fs_devices;
6331
6332 fs_devices->seeding = 1;
6333 fs_devices->opened = 1;
6334 return fs_devices;
6335 }
6336
6337 fs_devices = clone_fs_devices(fs_devices);
6338 if (IS_ERR(fs_devices))
6339 return fs_devices;
6340
6341 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
6342 root->fs_info->bdev_holder);
6343 if (ret) {
6344 free_fs_devices(fs_devices);
6345 fs_devices = ERR_PTR(ret);
6346 goto out;
6347 }
6348
6349 if (!fs_devices->seeding) {
6350 __btrfs_close_devices(fs_devices);
6351 free_fs_devices(fs_devices);
6352 fs_devices = ERR_PTR(-EINVAL);
6353 goto out;
6354 }
6355
6356 fs_devices->seed = root->fs_info->fs_devices->seed;
6357 root->fs_info->fs_devices->seed = fs_devices;
6358 out:
6359 return fs_devices;
6360 }
6361
6362 static int read_one_dev(struct btrfs_root *root,
6363 struct extent_buffer *leaf,
6364 struct btrfs_dev_item *dev_item)
6365 {
6366 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6367 struct btrfs_device *device;
6368 u64 devid;
6369 int ret;
6370 u8 fs_uuid[BTRFS_UUID_SIZE];
6371 u8 dev_uuid[BTRFS_UUID_SIZE];
6372
6373 devid = btrfs_device_id(leaf, dev_item);
6374 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
6375 BTRFS_UUID_SIZE);
6376 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
6377 BTRFS_UUID_SIZE);
6378
6379 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
6380 fs_devices = open_seed_devices(root, fs_uuid);
6381 if (IS_ERR(fs_devices))
6382 return PTR_ERR(fs_devices);
6383 }
6384
6385 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
6386 if (!device) {
6387 if (!btrfs_test_opt(root, DEGRADED))
6388 return -EIO;
6389
6390 device = add_missing_dev(root, fs_devices, devid, dev_uuid);
6391 if (!device)
6392 return -ENOMEM;
6393 btrfs_warn(root->fs_info, "devid %llu uuid %pU missing",
6394 devid, dev_uuid);
6395 } else {
6396 if (!device->bdev && !btrfs_test_opt(root, DEGRADED))
6397 return -EIO;
6398
6399 if(!device->bdev && !device->missing) {
6400 /*
6401 * this happens when a device that was properly setup
6402 * in the device info lists suddenly goes bad.
6403 * device->bdev is NULL, and so we have to set
6404 * device->missing to one here
6405 */
6406 device->fs_devices->missing_devices++;
6407 device->missing = 1;
6408 }
6409
6410 /* Move the device to its own fs_devices */
6411 if (device->fs_devices != fs_devices) {
6412 ASSERT(device->missing);
6413
6414 list_move(&device->dev_list, &fs_devices->devices);
6415 device->fs_devices->num_devices--;
6416 fs_devices->num_devices++;
6417
6418 device->fs_devices->missing_devices--;
6419 fs_devices->missing_devices++;
6420
6421 device->fs_devices = fs_devices;
6422 }
6423 }
6424
6425 if (device->fs_devices != root->fs_info->fs_devices) {
6426 BUG_ON(device->writeable);
6427 if (device->generation !=
6428 btrfs_device_generation(leaf, dev_item))
6429 return -EINVAL;
6430 }
6431
6432 fill_device_from_item(leaf, dev_item, device);
6433 device->in_fs_metadata = 1;
6434 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
6435 device->fs_devices->total_rw_bytes += device->total_bytes;
6436 spin_lock(&root->fs_info->free_chunk_lock);
6437 root->fs_info->free_chunk_space += device->total_bytes -
6438 device->bytes_used;
6439 spin_unlock(&root->fs_info->free_chunk_lock);
6440 }
6441 ret = 0;
6442 return ret;
6443 }
6444
6445 int btrfs_read_sys_array(struct btrfs_root *root)
6446 {
6447 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
6448 struct extent_buffer *sb;
6449 struct btrfs_disk_key *disk_key;
6450 struct btrfs_chunk *chunk;
6451 u8 *array_ptr;
6452 unsigned long sb_array_offset;
6453 int ret = 0;
6454 u32 num_stripes;
6455 u32 array_size;
6456 u32 len = 0;
6457 u32 cur_offset;
6458 struct btrfs_key key;
6459
6460 ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
6461 /*
6462 * This will create extent buffer of nodesize, superblock size is
6463 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
6464 * overallocate but we can keep it as-is, only the first page is used.
6465 */
6466 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
6467 if (!sb)
6468 return -ENOMEM;
6469 btrfs_set_buffer_uptodate(sb);
6470 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
6471 /*
6472 * The sb extent buffer is artifical and just used to read the system array.
6473 * btrfs_set_buffer_uptodate() call does not properly mark all it's
6474 * pages up-to-date when the page is larger: extent does not cover the
6475 * whole page and consequently check_page_uptodate does not find all
6476 * the page's extents up-to-date (the hole beyond sb),
6477 * write_extent_buffer then triggers a WARN_ON.
6478 *
6479 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
6480 * but sb spans only this function. Add an explicit SetPageUptodate call
6481 * to silence the warning eg. on PowerPC 64.
6482 */
6483 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
6484 SetPageUptodate(sb->pages[0]);
6485
6486 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
6487 array_size = btrfs_super_sys_array_size(super_copy);
6488
6489 array_ptr = super_copy->sys_chunk_array;
6490 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
6491 cur_offset = 0;
6492
6493 while (cur_offset < array_size) {
6494 disk_key = (struct btrfs_disk_key *)array_ptr;
6495 len = sizeof(*disk_key);
6496 if (cur_offset + len > array_size)
6497 goto out_short_read;
6498
6499 btrfs_disk_key_to_cpu(&key, disk_key);
6500
6501 array_ptr += len;
6502 sb_array_offset += len;
6503 cur_offset += len;
6504
6505 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6506 chunk = (struct btrfs_chunk *)sb_array_offset;
6507 /*
6508 * At least one btrfs_chunk with one stripe must be
6509 * present, exact stripe count check comes afterwards
6510 */
6511 len = btrfs_chunk_item_size(1);
6512 if (cur_offset + len > array_size)
6513 goto out_short_read;
6514
6515 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
6516 len = btrfs_chunk_item_size(num_stripes);
6517 if (cur_offset + len > array_size)
6518 goto out_short_read;
6519
6520 ret = read_one_chunk(root, &key, sb, chunk);
6521 if (ret)
6522 break;
6523 } else {
6524 ret = -EIO;
6525 break;
6526 }
6527 array_ptr += len;
6528 sb_array_offset += len;
6529 cur_offset += len;
6530 }
6531 free_extent_buffer(sb);
6532 return ret;
6533
6534 out_short_read:
6535 printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
6536 len, cur_offset);
6537 free_extent_buffer(sb);
6538 return -EIO;
6539 }
6540
6541 int btrfs_read_chunk_tree(struct btrfs_root *root)
6542 {
6543 struct btrfs_path *path;
6544 struct extent_buffer *leaf;
6545 struct btrfs_key key;
6546 struct btrfs_key found_key;
6547 int ret;
6548 int slot;
6549
6550 root = root->fs_info->chunk_root;
6551
6552 path = btrfs_alloc_path();
6553 if (!path)
6554 return -ENOMEM;
6555
6556 mutex_lock(&uuid_mutex);
6557 lock_chunks(root);
6558
6559 /*
6560 * Read all device items, and then all the chunk items. All
6561 * device items are found before any chunk item (their object id
6562 * is smaller than the lowest possible object id for a chunk
6563 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
6564 */
6565 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
6566 key.offset = 0;
6567 key.type = 0;
6568 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6569 if (ret < 0)
6570 goto error;
6571 while (1) {
6572 leaf = path->nodes[0];
6573 slot = path->slots[0];
6574 if (slot >= btrfs_header_nritems(leaf)) {
6575 ret = btrfs_next_leaf(root, path);
6576 if (ret == 0)
6577 continue;
6578 if (ret < 0)
6579 goto error;
6580 break;
6581 }
6582 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6583 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
6584 struct btrfs_dev_item *dev_item;
6585 dev_item = btrfs_item_ptr(leaf, slot,
6586 struct btrfs_dev_item);
6587 ret = read_one_dev(root, leaf, dev_item);
6588 if (ret)
6589 goto error;
6590 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
6591 struct btrfs_chunk *chunk;
6592 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
6593 ret = read_one_chunk(root, &found_key, leaf, chunk);
6594 if (ret)
6595 goto error;
6596 }
6597 path->slots[0]++;
6598 }
6599 ret = 0;
6600 error:
6601 unlock_chunks(root);
6602 mutex_unlock(&uuid_mutex);
6603
6604 btrfs_free_path(path);
6605 return ret;
6606 }
6607
6608 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
6609 {
6610 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6611 struct btrfs_device *device;
6612
6613 while (fs_devices) {
6614 mutex_lock(&fs_devices->device_list_mutex);
6615 list_for_each_entry(device, &fs_devices->devices, dev_list)
6616 device->dev_root = fs_info->dev_root;
6617 mutex_unlock(&fs_devices->device_list_mutex);
6618
6619 fs_devices = fs_devices->seed;
6620 }
6621 }
6622
6623 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
6624 {
6625 int i;
6626
6627 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6628 btrfs_dev_stat_reset(dev, i);
6629 }
6630
6631 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
6632 {
6633 struct btrfs_key key;
6634 struct btrfs_key found_key;
6635 struct btrfs_root *dev_root = fs_info->dev_root;
6636 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6637 struct extent_buffer *eb;
6638 int slot;
6639 int ret = 0;
6640 struct btrfs_device *device;
6641 struct btrfs_path *path = NULL;
6642 int i;
6643
6644 path = btrfs_alloc_path();
6645 if (!path) {
6646 ret = -ENOMEM;
6647 goto out;
6648 }
6649
6650 mutex_lock(&fs_devices->device_list_mutex);
6651 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6652 int item_size;
6653 struct btrfs_dev_stats_item *ptr;
6654
6655 key.objectid = 0;
6656 key.type = BTRFS_DEV_STATS_KEY;
6657 key.offset = device->devid;
6658 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
6659 if (ret) {
6660 __btrfs_reset_dev_stats(device);
6661 device->dev_stats_valid = 1;
6662 btrfs_release_path(path);
6663 continue;
6664 }
6665 slot = path->slots[0];
6666 eb = path->nodes[0];
6667 btrfs_item_key_to_cpu(eb, &found_key, slot);
6668 item_size = btrfs_item_size_nr(eb, slot);
6669
6670 ptr = btrfs_item_ptr(eb, slot,
6671 struct btrfs_dev_stats_item);
6672
6673 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6674 if (item_size >= (1 + i) * sizeof(__le64))
6675 btrfs_dev_stat_set(device, i,
6676 btrfs_dev_stats_value(eb, ptr, i));
6677 else
6678 btrfs_dev_stat_reset(device, i);
6679 }
6680
6681 device->dev_stats_valid = 1;
6682 btrfs_dev_stat_print_on_load(device);
6683 btrfs_release_path(path);
6684 }
6685 mutex_unlock(&fs_devices->device_list_mutex);
6686
6687 out:
6688 btrfs_free_path(path);
6689 return ret < 0 ? ret : 0;
6690 }
6691
6692 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
6693 struct btrfs_root *dev_root,
6694 struct btrfs_device *device)
6695 {
6696 struct btrfs_path *path;
6697 struct btrfs_key key;
6698 struct extent_buffer *eb;
6699 struct btrfs_dev_stats_item *ptr;
6700 int ret;
6701 int i;
6702
6703 key.objectid = 0;
6704 key.type = BTRFS_DEV_STATS_KEY;
6705 key.offset = device->devid;
6706
6707 path = btrfs_alloc_path();
6708 BUG_ON(!path);
6709 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
6710 if (ret < 0) {
6711 btrfs_warn_in_rcu(dev_root->fs_info,
6712 "error %d while searching for dev_stats item for device %s",
6713 ret, rcu_str_deref(device->name));
6714 goto out;
6715 }
6716
6717 if (ret == 0 &&
6718 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
6719 /* need to delete old one and insert a new one */
6720 ret = btrfs_del_item(trans, dev_root, path);
6721 if (ret != 0) {
6722 btrfs_warn_in_rcu(dev_root->fs_info,
6723 "delete too small dev_stats item for device %s failed %d",
6724 rcu_str_deref(device->name), ret);
6725 goto out;
6726 }
6727 ret = 1;
6728 }
6729
6730 if (ret == 1) {
6731 /* need to insert a new item */
6732 btrfs_release_path(path);
6733 ret = btrfs_insert_empty_item(trans, dev_root, path,
6734 &key, sizeof(*ptr));
6735 if (ret < 0) {
6736 btrfs_warn_in_rcu(dev_root->fs_info,
6737 "insert dev_stats item for device %s failed %d",
6738 rcu_str_deref(device->name), ret);
6739 goto out;
6740 }
6741 }
6742
6743 eb = path->nodes[0];
6744 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
6745 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6746 btrfs_set_dev_stats_value(eb, ptr, i,
6747 btrfs_dev_stat_read(device, i));
6748 btrfs_mark_buffer_dirty(eb);
6749
6750 out:
6751 btrfs_free_path(path);
6752 return ret;
6753 }
6754
6755 /*
6756 * called from commit_transaction. Writes all changed device stats to disk.
6757 */
6758 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
6759 struct btrfs_fs_info *fs_info)
6760 {
6761 struct btrfs_root *dev_root = fs_info->dev_root;
6762 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6763 struct btrfs_device *device;
6764 int stats_cnt;
6765 int ret = 0;
6766
6767 mutex_lock(&fs_devices->device_list_mutex);
6768 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6769 if (!device->dev_stats_valid || !btrfs_dev_stats_dirty(device))
6770 continue;
6771
6772 stats_cnt = atomic_read(&device->dev_stats_ccnt);
6773 ret = update_dev_stat_item(trans, dev_root, device);
6774 if (!ret)
6775 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
6776 }
6777 mutex_unlock(&fs_devices->device_list_mutex);
6778
6779 return ret;
6780 }
6781
6782 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
6783 {
6784 btrfs_dev_stat_inc(dev, index);
6785 btrfs_dev_stat_print_on_error(dev);
6786 }
6787
6788 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
6789 {
6790 if (!dev->dev_stats_valid)
6791 return;
6792 btrfs_err_rl_in_rcu(dev->dev_root->fs_info,
6793 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
6794 rcu_str_deref(dev->name),
6795 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6796 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6797 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6798 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6799 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6800 }
6801
6802 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
6803 {
6804 int i;
6805
6806 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6807 if (btrfs_dev_stat_read(dev, i) != 0)
6808 break;
6809 if (i == BTRFS_DEV_STAT_VALUES_MAX)
6810 return; /* all values == 0, suppress message */
6811
6812 btrfs_info_in_rcu(dev->dev_root->fs_info,
6813 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
6814 rcu_str_deref(dev->name),
6815 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6816 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6817 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6818 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6819 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6820 }
6821
6822 int btrfs_get_dev_stats(struct btrfs_root *root,
6823 struct btrfs_ioctl_get_dev_stats *stats)
6824 {
6825 struct btrfs_device *dev;
6826 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6827 int i;
6828
6829 mutex_lock(&fs_devices->device_list_mutex);
6830 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
6831 mutex_unlock(&fs_devices->device_list_mutex);
6832
6833 if (!dev) {
6834 btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
6835 return -ENODEV;
6836 } else if (!dev->dev_stats_valid) {
6837 btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
6838 return -ENODEV;
6839 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
6840 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6841 if (stats->nr_items > i)
6842 stats->values[i] =
6843 btrfs_dev_stat_read_and_reset(dev, i);
6844 else
6845 btrfs_dev_stat_reset(dev, i);
6846 }
6847 } else {
6848 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6849 if (stats->nr_items > i)
6850 stats->values[i] = btrfs_dev_stat_read(dev, i);
6851 }
6852 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
6853 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
6854 return 0;
6855 }
6856
6857 void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path)
6858 {
6859 struct buffer_head *bh;
6860 struct btrfs_super_block *disk_super;
6861 int copy_num;
6862
6863 if (!bdev)
6864 return;
6865
6866 for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX;
6867 copy_num++) {
6868
6869 if (btrfs_read_dev_one_super(bdev, copy_num, &bh))
6870 continue;
6871
6872 disk_super = (struct btrfs_super_block *)bh->b_data;
6873
6874 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
6875 set_buffer_dirty(bh);
6876 sync_dirty_buffer(bh);
6877 brelse(bh);
6878 }
6879
6880 /* Notify udev that device has changed */
6881 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
6882
6883 /* Update ctime/mtime for device path for libblkid */
6884 update_dev_time(device_path);
6885 }
6886
6887 /*
6888 * Update the size of all devices, which is used for writing out the
6889 * super blocks.
6890 */
6891 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info)
6892 {
6893 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6894 struct btrfs_device *curr, *next;
6895
6896 if (list_empty(&fs_devices->resized_devices))
6897 return;
6898
6899 mutex_lock(&fs_devices->device_list_mutex);
6900 lock_chunks(fs_info->dev_root);
6901 list_for_each_entry_safe(curr, next, &fs_devices->resized_devices,
6902 resized_list) {
6903 list_del_init(&curr->resized_list);
6904 curr->commit_total_bytes = curr->disk_total_bytes;
6905 }
6906 unlock_chunks(fs_info->dev_root);
6907 mutex_unlock(&fs_devices->device_list_mutex);
6908 }
6909
6910 /* Must be invoked during the transaction commit */
6911 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
6912 struct btrfs_transaction *transaction)
6913 {
6914 struct extent_map *em;
6915 struct map_lookup *map;
6916 struct btrfs_device *dev;
6917 int i;
6918
6919 if (list_empty(&transaction->pending_chunks))
6920 return;
6921
6922 /* In order to kick the device replace finish process */
6923 lock_chunks(root);
6924 list_for_each_entry(em, &transaction->pending_chunks, list) {
6925 map = (struct map_lookup *)em->bdev;
6926
6927 for (i = 0; i < map->num_stripes; i++) {
6928 dev = map->stripes[i].dev;
6929 dev->commit_bytes_used = dev->bytes_used;
6930 }
6931 }
6932 unlock_chunks(root);
6933 }
6934
6935 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info)
6936 {
6937 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6938 while (fs_devices) {
6939 fs_devices->fs_info = fs_info;
6940 fs_devices = fs_devices->seed;
6941 }
6942 }
6943
6944 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info)
6945 {
6946 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6947 while (fs_devices) {
6948 fs_devices->fs_info = NULL;
6949 fs_devices = fs_devices->seed;
6950 }
6951 }
6952
6953 void btrfs_close_one_device(struct btrfs_device *device)
6954 {
6955 struct btrfs_fs_devices *fs_devices = device->fs_devices;
6956 struct btrfs_device *new_device;
6957 struct rcu_string *name;
6958
6959 if (device->bdev)
6960 fs_devices->open_devices--;
6961
6962 if (device->writeable &&
6963 device->devid != BTRFS_DEV_REPLACE_DEVID) {
6964 list_del_init(&device->dev_alloc_list);
6965 fs_devices->rw_devices--;
6966 }
6967
6968 if (device->missing)
6969 fs_devices->missing_devices--;
6970
6971 new_device = btrfs_alloc_device(NULL, &device->devid,
6972 device->uuid);
6973 BUG_ON(IS_ERR(new_device)); /* -ENOMEM */
6974
6975 /* Safe because we are under uuid_mutex */
6976 if (device->name) {
6977 name = rcu_string_strdup(device->name->str, GFP_NOFS);
6978 BUG_ON(!name); /* -ENOMEM */
6979 rcu_assign_pointer(new_device->name, name);
6980 }
6981
6982 list_replace_rcu(&device->dev_list, &new_device->dev_list);
6983 new_device->fs_devices = device->fs_devices;
6984
6985 call_rcu(&device->rcu, free_device);
6986 }
Linux with added FPC-III support