?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
ocfs2: fix locking for res->tracking and dlm->tracking_list
[linux/fpc-iii.git] / fs / btrfs / volumes.c
blobb4d63a9842fac69d3e0854bfbefbc52d80509efb
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 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 btrfs_device_data_ordered_init(dev);
236 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
237 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
238
239 return dev;
240 }
241
242 static noinline struct btrfs_device *__find_device(struct list_head *head,
243 u64 devid, u8 *uuid)
244 {
245 struct btrfs_device *dev;
246
247 list_for_each_entry(dev, head, dev_list) {
248 if (dev->devid == devid &&
249 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
250 return dev;
251 }
252 }
253 return NULL;
254 }
255
256 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
257 {
258 struct btrfs_fs_devices *fs_devices;
259
260 list_for_each_entry(fs_devices, &fs_uuids, list) {
261 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
262 return fs_devices;
263 }
264 return NULL;
265 }
266
267 static int
268 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
269 int flush, struct block_device **bdev,
270 struct buffer_head **bh)
271 {
272 int ret;
273
274 *bdev = blkdev_get_by_path(device_path, flags, holder);
275
276 if (IS_ERR(*bdev)) {
277 ret = PTR_ERR(*bdev);
278 goto error;
279 }
280
281 if (flush)
282 filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
283 ret = set_blocksize(*bdev, 4096);
284 if (ret) {
285 blkdev_put(*bdev, flags);
286 goto error;
287 }
288 invalidate_bdev(*bdev);
289 *bh = btrfs_read_dev_super(*bdev);
290 if (IS_ERR(*bh)) {
291 ret = PTR_ERR(*bh);
292 blkdev_put(*bdev, flags);
293 goto error;
294 }
295
296 return 0;
297
298 error:
299 *bdev = NULL;
300 *bh = NULL;
301 return ret;
302 }
303
304 static void requeue_list(struct btrfs_pending_bios *pending_bios,
305 struct bio *head, struct bio *tail)
306 {
307
308 struct bio *old_head;
309
310 old_head = pending_bios->head;
311 pending_bios->head = head;
312 if (pending_bios->tail)
313 tail->bi_next = old_head;
314 else
315 pending_bios->tail = tail;
316 }
317
318 /*
319 * we try to collect pending bios for a device so we don't get a large
320 * number of procs sending bios down to the same device. This greatly
321 * improves the schedulers ability to collect and merge the bios.
322 *
323 * But, it also turns into a long list of bios to process and that is sure
324 * to eventually make the worker thread block. The solution here is to
325 * make some progress and then put this work struct back at the end of
326 * the list if the block device is congested. This way, multiple devices
327 * can make progress from a single worker thread.
328 */
329 static noinline void run_scheduled_bios(struct btrfs_device *device)
330 {
331 struct bio *pending;
332 struct backing_dev_info *bdi;
333 struct btrfs_fs_info *fs_info;
334 struct btrfs_pending_bios *pending_bios;
335 struct bio *tail;
336 struct bio *cur;
337 int again = 0;
338 unsigned long num_run;
339 unsigned long batch_run = 0;
340 unsigned long limit;
341 unsigned long last_waited = 0;
342 int force_reg = 0;
343 int sync_pending = 0;
344 struct blk_plug plug;
345
346 /*
347 * this function runs all the bios we've collected for
348 * a particular device. We don't want to wander off to
349 * another device without first sending all of these down.
350 * So, setup a plug here and finish it off before we return
351 */
352 blk_start_plug(&plug);
353
354 bdi = blk_get_backing_dev_info(device->bdev);
355 fs_info = device->dev_root->fs_info;
356 limit = btrfs_async_submit_limit(fs_info);
357 limit = limit * 2 / 3;
358
359 loop:
360 spin_lock(&device->io_lock);
361
362 loop_lock:
363 num_run = 0;
364
365 /* take all the bios off the list at once and process them
366 * later on (without the lock held). But, remember the
367 * tail and other pointers so the bios can be properly reinserted
368 * into the list if we hit congestion
369 */
370 if (!force_reg && device->pending_sync_bios.head) {
371 pending_bios = &device->pending_sync_bios;
372 force_reg = 1;
373 } else {
374 pending_bios = &device->pending_bios;
375 force_reg = 0;
376 }
377
378 pending = pending_bios->head;
379 tail = pending_bios->tail;
380 WARN_ON(pending && !tail);
381
382 /*
383 * if pending was null this time around, no bios need processing
384 * at all and we can stop. Otherwise it'll loop back up again
385 * and do an additional check so no bios are missed.
386 *
387 * device->running_pending is used to synchronize with the
388 * schedule_bio code.
389 */
390 if (device->pending_sync_bios.head == NULL &&
391 device->pending_bios.head == NULL) {
392 again = 0;
393 device->running_pending = 0;
394 } else {
395 again = 1;
396 device->running_pending = 1;
397 }
398
399 pending_bios->head = NULL;
400 pending_bios->tail = NULL;
401
402 spin_unlock(&device->io_lock);
403
404 while (pending) {
405
406 rmb();
407 /* we want to work on both lists, but do more bios on the
408 * sync list than the regular list
409 */
410 if ((num_run > 32 &&
411 pending_bios != &device->pending_sync_bios &&
412 device->pending_sync_bios.head) ||
413 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
414 device->pending_bios.head)) {
415 spin_lock(&device->io_lock);
416 requeue_list(pending_bios, pending, tail);
417 goto loop_lock;
418 }
419
420 cur = pending;
421 pending = pending->bi_next;
422 cur->bi_next = NULL;
423
424 /*
425 * atomic_dec_return implies a barrier for waitqueue_active
426 */
427 if (atomic_dec_return(&fs_info->nr_async_bios) < limit &&
428 waitqueue_active(&fs_info->async_submit_wait))
429 wake_up(&fs_info->async_submit_wait);
430
431 BUG_ON(atomic_read(&cur->__bi_cnt) == 0);
432
433 /*
434 * if we're doing the sync list, record that our
435 * plug has some sync requests on it
436 *
437 * If we're doing the regular list and there are
438 * sync requests sitting around, unplug before
439 * we add more
440 */
441 if (pending_bios == &device->pending_sync_bios) {
442 sync_pending = 1;
443 } else if (sync_pending) {
444 blk_finish_plug(&plug);
445 blk_start_plug(&plug);
446 sync_pending = 0;
447 }
448
449 btrfsic_submit_bio(cur->bi_rw, cur);
450 num_run++;
451 batch_run++;
452
453 cond_resched();
454
455 /*
456 * we made progress, there is more work to do and the bdi
457 * is now congested. Back off and let other work structs
458 * run instead
459 */
460 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
461 fs_info->fs_devices->open_devices > 1) {
462 struct io_context *ioc;
463
464 ioc = current->io_context;
465
466 /*
467 * the main goal here is that we don't want to
468 * block if we're going to be able to submit
469 * more requests without blocking.
470 *
471 * This code does two great things, it pokes into
472 * the elevator code from a filesystem _and_
473 * it makes assumptions about how batching works.
474 */
475 if (ioc && ioc->nr_batch_requests > 0 &&
476 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
477 (last_waited == 0 ||
478 ioc->last_waited == last_waited)) {
479 /*
480 * we want to go through our batch of
481 * requests and stop. So, we copy out
482 * the ioc->last_waited time and test
483 * against it before looping
484 */
485 last_waited = ioc->last_waited;
486 cond_resched();
487 continue;
488 }
489 spin_lock(&device->io_lock);
490 requeue_list(pending_bios, pending, tail);
491 device->running_pending = 1;
492
493 spin_unlock(&device->io_lock);
494 btrfs_queue_work(fs_info->submit_workers,
495 &device->work);
496 goto done;
497 }
498 /* unplug every 64 requests just for good measure */
499 if (batch_run % 64 == 0) {
500 blk_finish_plug(&plug);
501 blk_start_plug(&plug);
502 sync_pending = 0;
503 }
504 }
505
506 cond_resched();
507 if (again)
508 goto loop;
509
510 spin_lock(&device->io_lock);
511 if (device->pending_bios.head || device->pending_sync_bios.head)
512 goto loop_lock;
513 spin_unlock(&device->io_lock);
514
515 done:
516 blk_finish_plug(&plug);
517 }
518
519 static void pending_bios_fn(struct btrfs_work *work)
520 {
521 struct btrfs_device *device;
522
523 device = container_of(work, struct btrfs_device, work);
524 run_scheduled_bios(device);
525 }
526
527
528 void btrfs_free_stale_device(struct btrfs_device *cur_dev)
529 {
530 struct btrfs_fs_devices *fs_devs;
531 struct btrfs_device *dev;
532
533 if (!cur_dev->name)
534 return;
535
536 list_for_each_entry(fs_devs, &fs_uuids, list) {
537 int del = 1;
538
539 if (fs_devs->opened)
540 continue;
541 if (fs_devs->seeding)
542 continue;
543
544 list_for_each_entry(dev, &fs_devs->devices, dev_list) {
545
546 if (dev == cur_dev)
547 continue;
548 if (!dev->name)
549 continue;
550
551 /*
552 * Todo: This won't be enough. What if the same device
553 * comes back (with new uuid and) with its mapper path?
554 * But for now, this does help as mostly an admin will
555 * either use mapper or non mapper path throughout.
556 */
557 rcu_read_lock();
558 del = strcmp(rcu_str_deref(dev->name),
559 rcu_str_deref(cur_dev->name));
560 rcu_read_unlock();
561 if (!del)
562 break;
563 }
564
565 if (!del) {
566 /* delete the stale device */
567 if (fs_devs->num_devices == 1) {
568 btrfs_sysfs_remove_fsid(fs_devs);
569 list_del(&fs_devs->list);
570 free_fs_devices(fs_devs);
571 break;
572 } else {
573 fs_devs->num_devices--;
574 list_del(&dev->dev_list);
575 rcu_string_free(dev->name);
576 kfree(dev);
577 }
578 break;
579 }
580 }
581 }
582
583 /*
584 * Add new device to list of registered devices
585 *
586 * Returns:
587 * 1 - first time device is seen
588 * 0 - device already known
589 * < 0 - error
590 */
591 static noinline int device_list_add(const char *path,
592 struct btrfs_super_block *disk_super,
593 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
594 {
595 struct btrfs_device *device;
596 struct btrfs_fs_devices *fs_devices;
597 struct rcu_string *name;
598 int ret = 0;
599 u64 found_transid = btrfs_super_generation(disk_super);
600
601 fs_devices = find_fsid(disk_super->fsid);
602 if (!fs_devices) {
603 fs_devices = alloc_fs_devices(disk_super->fsid);
604 if (IS_ERR(fs_devices))
605 return PTR_ERR(fs_devices);
606
607 list_add(&fs_devices->list, &fs_uuids);
608
609 device = NULL;
610 } else {
611 device = __find_device(&fs_devices->devices, devid,
612 disk_super->dev_item.uuid);
613 }
614
615 if (!device) {
616 if (fs_devices->opened)
617 return -EBUSY;
618
619 device = btrfs_alloc_device(NULL, &devid,
620 disk_super->dev_item.uuid);
621 if (IS_ERR(device)) {
622 /* we can safely leave the fs_devices entry around */
623 return PTR_ERR(device);
624 }
625
626 name = rcu_string_strdup(path, GFP_NOFS);
627 if (!name) {
628 kfree(device);
629 return -ENOMEM;
630 }
631 rcu_assign_pointer(device->name, name);
632
633 mutex_lock(&fs_devices->device_list_mutex);
634 list_add_rcu(&device->dev_list, &fs_devices->devices);
635 fs_devices->num_devices++;
636 mutex_unlock(&fs_devices->device_list_mutex);
637
638 ret = 1;
639 device->fs_devices = fs_devices;
640 } else if (!device->name || strcmp(device->name->str, path)) {
641 /*
642 * When FS is already mounted.
643 * 1. If you are here and if the device->name is NULL that
644 * means this device was missing at time of FS mount.
645 * 2. If you are here and if the device->name is different
646 * from 'path' that means either
647 * a. The same device disappeared and reappeared with
648 * different name. or
649 * b. The missing-disk-which-was-replaced, has
650 * reappeared now.
651 *
652 * We must allow 1 and 2a above. But 2b would be a spurious
653 * and unintentional.
654 *
655 * Further in case of 1 and 2a above, the disk at 'path'
656 * would have missed some transaction when it was away and
657 * in case of 2a the stale bdev has to be updated as well.
658 * 2b must not be allowed at all time.
659 */
660
661 /*
662 * For now, we do allow update to btrfs_fs_device through the
663 * btrfs dev scan cli after FS has been mounted. We're still
664 * tracking a problem where systems fail mount by subvolume id
665 * when we reject replacement on a mounted FS.
666 */
667 if (!fs_devices->opened && found_transid < device->generation) {
668 /*
669 * That is if the FS is _not_ mounted and if you
670 * are here, that means there is more than one
671 * disk with same uuid and devid.We keep the one
672 * with larger generation number or the last-in if
673 * generation are equal.
674 */
675 return -EEXIST;
676 }
677
678 name = rcu_string_strdup(path, GFP_NOFS);
679 if (!name)
680 return -ENOMEM;
681 rcu_string_free(device->name);
682 rcu_assign_pointer(device->name, name);
683 if (device->missing) {
684 fs_devices->missing_devices--;
685 device->missing = 0;
686 }
687 }
688
689 /*
690 * Unmount does not free the btrfs_device struct but would zero
691 * generation along with most of the other members. So just update
692 * it back. We need it to pick the disk with largest generation
693 * (as above).
694 */
695 if (!fs_devices->opened)
696 device->generation = found_transid;
697
698 /*
699 * if there is new btrfs on an already registered device,
700 * then remove the stale device entry.
701 */
702 btrfs_free_stale_device(device);
703
704 *fs_devices_ret = fs_devices;
705
706 return ret;
707 }
708
709 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
710 {
711 struct btrfs_fs_devices *fs_devices;
712 struct btrfs_device *device;
713 struct btrfs_device *orig_dev;
714
715 fs_devices = alloc_fs_devices(orig->fsid);
716 if (IS_ERR(fs_devices))
717 return fs_devices;
718
719 mutex_lock(&orig->device_list_mutex);
720 fs_devices->total_devices = orig->total_devices;
721
722 /* We have held the volume lock, it is safe to get the devices. */
723 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
724 struct rcu_string *name;
725
726 device = btrfs_alloc_device(NULL, &orig_dev->devid,
727 orig_dev->uuid);
728 if (IS_ERR(device))
729 goto error;
730
731 /*
732 * This is ok to do without rcu read locked because we hold the
733 * uuid mutex so nothing we touch in here is going to disappear.
734 */
735 if (orig_dev->name) {
736 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
737 if (!name) {
738 kfree(device);
739 goto error;
740 }
741 rcu_assign_pointer(device->name, name);
742 }
743
744 list_add(&device->dev_list, &fs_devices->devices);
745 device->fs_devices = fs_devices;
746 fs_devices->num_devices++;
747 }
748 mutex_unlock(&orig->device_list_mutex);
749 return fs_devices;
750 error:
751 mutex_unlock(&orig->device_list_mutex);
752 free_fs_devices(fs_devices);
753 return ERR_PTR(-ENOMEM);
754 }
755
756 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step)
757 {
758 struct btrfs_device *device, *next;
759 struct btrfs_device *latest_dev = NULL;
760
761 mutex_lock(&uuid_mutex);
762 again:
763 /* This is the initialized path, it is safe to release the devices. */
764 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
765 if (device->in_fs_metadata) {
766 if (!device->is_tgtdev_for_dev_replace &&
767 (!latest_dev ||
768 device->generation > latest_dev->generation)) {
769 latest_dev = device;
770 }
771 continue;
772 }
773
774 if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
775 /*
776 * In the first step, keep the device which has
777 * the correct fsid and the devid that is used
778 * for the dev_replace procedure.
779 * In the second step, the dev_replace state is
780 * read from the device tree and it is known
781 * whether the procedure is really active or
782 * not, which means whether this device is
783 * used or whether it should be removed.
784 */
785 if (step == 0 || device->is_tgtdev_for_dev_replace) {
786 continue;
787 }
788 }
789 if (device->bdev) {
790 blkdev_put(device->bdev, device->mode);
791 device->bdev = NULL;
792 fs_devices->open_devices--;
793 }
794 if (device->writeable) {
795 list_del_init(&device->dev_alloc_list);
796 device->writeable = 0;
797 if (!device->is_tgtdev_for_dev_replace)
798 fs_devices->rw_devices--;
799 }
800 list_del_init(&device->dev_list);
801 fs_devices->num_devices--;
802 rcu_string_free(device->name);
803 kfree(device);
804 }
805
806 if (fs_devices->seed) {
807 fs_devices = fs_devices->seed;
808 goto again;
809 }
810
811 fs_devices->latest_bdev = latest_dev->bdev;
812
813 mutex_unlock(&uuid_mutex);
814 }
815
816 static void __free_device(struct work_struct *work)
817 {
818 struct btrfs_device *device;
819
820 device = container_of(work, struct btrfs_device, rcu_work);
821
822 if (device->bdev)
823 blkdev_put(device->bdev, device->mode);
824
825 rcu_string_free(device->name);
826 kfree(device);
827 }
828
829 static void free_device(struct rcu_head *head)
830 {
831 struct btrfs_device *device;
832
833 device = container_of(head, struct btrfs_device, rcu);
834
835 INIT_WORK(&device->rcu_work, __free_device);
836 schedule_work(&device->rcu_work);
837 }
838
839 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
840 {
841 struct btrfs_device *device, *tmp;
842
843 if (--fs_devices->opened > 0)
844 return 0;
845
846 mutex_lock(&fs_devices->device_list_mutex);
847 list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list) {
848 btrfs_close_one_device(device);
849 }
850 mutex_unlock(&fs_devices->device_list_mutex);
851
852 WARN_ON(fs_devices->open_devices);
853 WARN_ON(fs_devices->rw_devices);
854 fs_devices->opened = 0;
855 fs_devices->seeding = 0;
856
857 return 0;
858 }
859
860 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
861 {
862 struct btrfs_fs_devices *seed_devices = NULL;
863 int ret;
864
865 mutex_lock(&uuid_mutex);
866 ret = __btrfs_close_devices(fs_devices);
867 if (!fs_devices->opened) {
868 seed_devices = fs_devices->seed;
869 fs_devices->seed = NULL;
870 }
871 mutex_unlock(&uuid_mutex);
872
873 while (seed_devices) {
874 fs_devices = seed_devices;
875 seed_devices = fs_devices->seed;
876 __btrfs_close_devices(fs_devices);
877 free_fs_devices(fs_devices);
878 }
879 /*
880 * Wait for rcu kworkers under __btrfs_close_devices
881 * to finish all blkdev_puts so device is really
882 * free when umount is done.
883 */
884 rcu_barrier();
885 return ret;
886 }
887
888 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
889 fmode_t flags, void *holder)
890 {
891 struct request_queue *q;
892 struct block_device *bdev;
893 struct list_head *head = &fs_devices->devices;
894 struct btrfs_device *device;
895 struct btrfs_device *latest_dev = NULL;
896 struct buffer_head *bh;
897 struct btrfs_super_block *disk_super;
898 u64 devid;
899 int seeding = 1;
900 int ret = 0;
901
902 flags |= FMODE_EXCL;
903
904 list_for_each_entry(device, head, dev_list) {
905 if (device->bdev)
906 continue;
907 if (!device->name)
908 continue;
909
910 /* Just open everything we can; ignore failures here */
911 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
912 &bdev, &bh))
913 continue;
914
915 disk_super = (struct btrfs_super_block *)bh->b_data;
916 devid = btrfs_stack_device_id(&disk_super->dev_item);
917 if (devid != device->devid)
918 goto error_brelse;
919
920 if (memcmp(device->uuid, disk_super->dev_item.uuid,
921 BTRFS_UUID_SIZE))
922 goto error_brelse;
923
924 device->generation = btrfs_super_generation(disk_super);
925 if (!latest_dev ||
926 device->generation > latest_dev->generation)
927 latest_dev = device;
928
929 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
930 device->writeable = 0;
931 } else {
932 device->writeable = !bdev_read_only(bdev);
933 seeding = 0;
934 }
935
936 q = bdev_get_queue(bdev);
937 if (blk_queue_discard(q))
938 device->can_discard = 1;
939
940 device->bdev = bdev;
941 device->in_fs_metadata = 0;
942 device->mode = flags;
943
944 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
945 fs_devices->rotating = 1;
946
947 fs_devices->open_devices++;
948 if (device->writeable &&
949 device->devid != BTRFS_DEV_REPLACE_DEVID) {
950 fs_devices->rw_devices++;
951 list_add(&device->dev_alloc_list,
952 &fs_devices->alloc_list);
953 }
954 brelse(bh);
955 continue;
956
957 error_brelse:
958 brelse(bh);
959 blkdev_put(bdev, flags);
960 continue;
961 }
962 if (fs_devices->open_devices == 0) {
963 ret = -EINVAL;
964 goto out;
965 }
966 fs_devices->seeding = seeding;
967 fs_devices->opened = 1;
968 fs_devices->latest_bdev = latest_dev->bdev;
969 fs_devices->total_rw_bytes = 0;
970 out:
971 return ret;
972 }
973
974 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
975 fmode_t flags, void *holder)
976 {
977 int ret;
978
979 mutex_lock(&uuid_mutex);
980 if (fs_devices->opened) {
981 fs_devices->opened++;
982 ret = 0;
983 } else {
984 ret = __btrfs_open_devices(fs_devices, flags, holder);
985 }
986 mutex_unlock(&uuid_mutex);
987 return ret;
988 }
989
990 /*
991 * Look for a btrfs signature on a device. This may be called out of the mount path
992 * and we are not allowed to call set_blocksize during the scan. The superblock
993 * is read via pagecache
994 */
995 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
996 struct btrfs_fs_devices **fs_devices_ret)
997 {
998 struct btrfs_super_block *disk_super;
999 struct block_device *bdev;
1000 struct page *page;
1001 void *p;
1002 int ret = -EINVAL;
1003 u64 devid;
1004 u64 transid;
1005 u64 total_devices;
1006 u64 bytenr;
1007 pgoff_t index;
1008
1009 /*
1010 * we would like to check all the supers, but that would make
1011 * a btrfs mount succeed after a mkfs from a different FS.
1012 * So, we need to add a special mount option to scan for
1013 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
1014 */
1015 bytenr = btrfs_sb_offset(0);
1016 flags |= FMODE_EXCL;
1017 mutex_lock(&uuid_mutex);
1018
1019 bdev = blkdev_get_by_path(path, flags, holder);
1020
1021 if (IS_ERR(bdev)) {
1022 ret = PTR_ERR(bdev);
1023 goto error;
1024 }
1025
1026 /* make sure our super fits in the device */
1027 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode))
1028 goto error_bdev_put;
1029
1030 /* make sure our super fits in the page */
1031 if (sizeof(*disk_super) > PAGE_CACHE_SIZE)
1032 goto error_bdev_put;
1033
1034 /* make sure our super doesn't straddle pages on disk */
1035 index = bytenr >> PAGE_CACHE_SHIFT;
1036 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index)
1037 goto error_bdev_put;
1038
1039 /* pull in the page with our super */
1040 page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
1041 index, GFP_NOFS);
1042
1043 if (IS_ERR_OR_NULL(page))
1044 goto error_bdev_put;
1045
1046 p = kmap(page);
1047
1048 /* align our pointer to the offset of the super block */
1049 disk_super = p + (bytenr & ~PAGE_CACHE_MASK);
1050
1051 if (btrfs_super_bytenr(disk_super) != bytenr ||
1052 btrfs_super_magic(disk_super) != BTRFS_MAGIC)
1053 goto error_unmap;
1054
1055 devid = btrfs_stack_device_id(&disk_super->dev_item);
1056 transid = btrfs_super_generation(disk_super);
1057 total_devices = btrfs_super_num_devices(disk_super);
1058
1059 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
1060 if (ret > 0) {
1061 if (disk_super->label[0]) {
1062 if (disk_super->label[BTRFS_LABEL_SIZE - 1])
1063 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
1064 printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
1065 } else {
1066 printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
1067 }
1068
1069 printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
1070 ret = 0;
1071 }
1072 if (!ret && fs_devices_ret)
1073 (*fs_devices_ret)->total_devices = total_devices;
1074
1075 error_unmap:
1076 kunmap(page);
1077 page_cache_release(page);
1078
1079 error_bdev_put:
1080 blkdev_put(bdev, flags);
1081 error:
1082 mutex_unlock(&uuid_mutex);
1083 return ret;
1084 }
1085
1086 /* helper to account the used device space in the range */
1087 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
1088 u64 end, u64 *length)
1089 {
1090 struct btrfs_key key;
1091 struct btrfs_root *root = device->dev_root;
1092 struct btrfs_dev_extent *dev_extent;
1093 struct btrfs_path *path;
1094 u64 extent_end;
1095 int ret;
1096 int slot;
1097 struct extent_buffer *l;
1098
1099 *length = 0;
1100
1101 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
1102 return 0;
1103
1104 path = btrfs_alloc_path();
1105 if (!path)
1106 return -ENOMEM;
1107 path->reada = 2;
1108
1109 key.objectid = device->devid;
1110 key.offset = start;
1111 key.type = BTRFS_DEV_EXTENT_KEY;
1112
1113 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1114 if (ret < 0)
1115 goto out;
1116 if (ret > 0) {
1117 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1118 if (ret < 0)
1119 goto out;
1120 }
1121
1122 while (1) {
1123 l = path->nodes[0];
1124 slot = path->slots[0];
1125 if (slot >= btrfs_header_nritems(l)) {
1126 ret = btrfs_next_leaf(root, path);
1127 if (ret == 0)
1128 continue;
1129 if (ret < 0)
1130 goto out;
1131
1132 break;
1133 }
1134 btrfs_item_key_to_cpu(l, &key, slot);
1135
1136 if (key.objectid < device->devid)
1137 goto next;
1138
1139 if (key.objectid > device->devid)
1140 break;
1141
1142 if (key.type != BTRFS_DEV_EXTENT_KEY)
1143 goto next;
1144
1145 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1146 extent_end = key.offset + btrfs_dev_extent_length(l,
1147 dev_extent);
1148 if (key.offset <= start && extent_end > end) {
1149 *length = end - start + 1;
1150 break;
1151 } else if (key.offset <= start && extent_end > start)
1152 *length += extent_end - start;
1153 else if (key.offset > start && extent_end <= end)
1154 *length += extent_end - key.offset;
1155 else if (key.offset > start && key.offset <= end) {
1156 *length += end - key.offset + 1;
1157 break;
1158 } else if (key.offset > end)
1159 break;
1160
1161 next:
1162 path->slots[0]++;
1163 }
1164 ret = 0;
1165 out:
1166 btrfs_free_path(path);
1167 return ret;
1168 }
1169
1170 static int contains_pending_extent(struct btrfs_transaction *transaction,
1171 struct btrfs_device *device,
1172 u64 *start, u64 len)
1173 {
1174 struct btrfs_fs_info *fs_info = device->dev_root->fs_info;
1175 struct extent_map *em;
1176 struct list_head *search_list = &fs_info->pinned_chunks;
1177 int ret = 0;
1178 u64 physical_start = *start;
1179
1180 if (transaction)
1181 search_list = &transaction->pending_chunks;
1182 again:
1183 list_for_each_entry(em, search_list, list) {
1184 struct map_lookup *map;
1185 int i;
1186
1187 map = (struct map_lookup *)em->bdev;
1188 for (i = 0; i < map->num_stripes; i++) {
1189 u64 end;
1190
1191 if (map->stripes[i].dev != device)
1192 continue;
1193 if (map->stripes[i].physical >= physical_start + len ||
1194 map->stripes[i].physical + em->orig_block_len <=
1195 physical_start)
1196 continue;
1197 /*
1198 * Make sure that while processing the pinned list we do
1199 * not override our *start with a lower value, because
1200 * we can have pinned chunks that fall within this
1201 * device hole and that have lower physical addresses
1202 * than the pending chunks we processed before. If we
1203 * do not take this special care we can end up getting
1204 * 2 pending chunks that start at the same physical
1205 * device offsets because the end offset of a pinned
1206 * chunk can be equal to the start offset of some
1207 * pending chunk.
1208 */
1209 end = map->stripes[i].physical + em->orig_block_len;
1210 if (end > *start) {
1211 *start = end;
1212 ret = 1;
1213 }
1214 }
1215 }
1216 if (search_list != &fs_info->pinned_chunks) {
1217 search_list = &fs_info->pinned_chunks;
1218 goto again;
1219 }
1220
1221 return ret;
1222 }
1223
1224
1225 /*
1226 * find_free_dev_extent_start - find free space in the specified device
1227 * @device: the device which we search the free space in
1228 * @num_bytes: the size of the free space that we need
1229 * @search_start: the position from which to begin the search
1230 * @start: store the start of the free space.
1231 * @len: the size of the free space. that we find, or the size
1232 * of the max free space if we don't find suitable free space
1233 *
1234 * this uses a pretty simple search, the expectation is that it is
1235 * called very infrequently and that a given device has a small number
1236 * of extents
1237 *
1238 * @start is used to store the start of the free space if we find. But if we
1239 * don't find suitable free space, it will be used to store the start position
1240 * of the max free space.
1241 *
1242 * @len is used to store the size of the free space that we find.
1243 * But if we don't find suitable free space, it is used to store the size of
1244 * the max free space.
1245 */
1246 int find_free_dev_extent_start(struct btrfs_transaction *transaction,
1247 struct btrfs_device *device, u64 num_bytes,
1248 u64 search_start, u64 *start, u64 *len)
1249 {
1250 struct btrfs_key key;
1251 struct btrfs_root *root = device->dev_root;
1252 struct btrfs_dev_extent *dev_extent;
1253 struct btrfs_path *path;
1254 u64 hole_size;
1255 u64 max_hole_start;
1256 u64 max_hole_size;
1257 u64 extent_end;
1258 u64 search_end = device->total_bytes;
1259 int ret;
1260 int slot;
1261 struct extent_buffer *l;
1262 u64 min_search_start;
1263
1264 /*
1265 * We don't want to overwrite the superblock on the drive nor any area
1266 * used by the boot loader (grub for example), so we make sure to start
1267 * at an offset of at least 1MB.
1268 */
1269 min_search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
1270 search_start = max(search_start, min_search_start);
1271
1272 path = btrfs_alloc_path();
1273 if (!path)
1274 return -ENOMEM;
1275
1276 max_hole_start = search_start;
1277 max_hole_size = 0;
1278
1279 again:
1280 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
1281 ret = -ENOSPC;
1282 goto out;
1283 }
1284
1285 path->reada = 2;
1286 path->search_commit_root = 1;
1287 path->skip_locking = 1;
1288
1289 key.objectid = device->devid;
1290 key.offset = search_start;
1291 key.type = BTRFS_DEV_EXTENT_KEY;
1292
1293 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1294 if (ret < 0)
1295 goto out;
1296 if (ret > 0) {
1297 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1298 if (ret < 0)
1299 goto out;
1300 }
1301
1302 while (1) {
1303 l = path->nodes[0];
1304 slot = path->slots[0];
1305 if (slot >= btrfs_header_nritems(l)) {
1306 ret = btrfs_next_leaf(root, path);
1307 if (ret == 0)
1308 continue;
1309 if (ret < 0)
1310 goto out;
1311
1312 break;
1313 }
1314 btrfs_item_key_to_cpu(l, &key, slot);
1315
1316 if (key.objectid < device->devid)
1317 goto next;
1318
1319 if (key.objectid > device->devid)
1320 break;
1321
1322 if (key.type != BTRFS_DEV_EXTENT_KEY)
1323 goto next;
1324
1325 if (key.offset > search_start) {
1326 hole_size = key.offset - search_start;
1327
1328 /*
1329 * Have to check before we set max_hole_start, otherwise
1330 * we could end up sending back this offset anyway.
1331 */
1332 if (contains_pending_extent(transaction, device,
1333 &search_start,
1334 hole_size)) {
1335 if (key.offset >= search_start) {
1336 hole_size = key.offset - search_start;
1337 } else {
1338 WARN_ON_ONCE(1);
1339 hole_size = 0;
1340 }
1341 }
1342
1343 if (hole_size > max_hole_size) {
1344 max_hole_start = search_start;
1345 max_hole_size = hole_size;
1346 }
1347
1348 /*
1349 * If this free space is greater than which we need,
1350 * it must be the max free space that we have found
1351 * until now, so max_hole_start must point to the start
1352 * of this free space and the length of this free space
1353 * is stored in max_hole_size. Thus, we return
1354 * max_hole_start and max_hole_size and go back to the
1355 * caller.
1356 */
1357 if (hole_size >= num_bytes) {
1358 ret = 0;
1359 goto out;
1360 }
1361 }
1362
1363 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1364 extent_end = key.offset + btrfs_dev_extent_length(l,
1365 dev_extent);
1366 if (extent_end > search_start)
1367 search_start = extent_end;
1368 next:
1369 path->slots[0]++;
1370 cond_resched();
1371 }
1372
1373 /*
1374 * At this point, search_start should be the end of
1375 * allocated dev extents, and when shrinking the device,
1376 * search_end may be smaller than search_start.
1377 */
1378 if (search_end > search_start) {
1379 hole_size = search_end - search_start;
1380
1381 if (contains_pending_extent(transaction, device, &search_start,
1382 hole_size)) {
1383 btrfs_release_path(path);
1384 goto again;
1385 }
1386
1387 if (hole_size > max_hole_size) {
1388 max_hole_start = search_start;
1389 max_hole_size = hole_size;
1390 }
1391 }
1392
1393 /* See above. */
1394 if (max_hole_size < num_bytes)
1395 ret = -ENOSPC;
1396 else
1397 ret = 0;
1398
1399 out:
1400 btrfs_free_path(path);
1401 *start = max_hole_start;
1402 if (len)
1403 *len = max_hole_size;
1404 return ret;
1405 }
1406
1407 int find_free_dev_extent(struct btrfs_trans_handle *trans,
1408 struct btrfs_device *device, u64 num_bytes,
1409 u64 *start, u64 *len)
1410 {
1411 /* FIXME use last free of some kind */
1412 return find_free_dev_extent_start(trans->transaction, device,
1413 num_bytes, 0, start, len);
1414 }
1415
1416 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1417 struct btrfs_device *device,
1418 u64 start, u64 *dev_extent_len)
1419 {
1420 int ret;
1421 struct btrfs_path *path;
1422 struct btrfs_root *root = device->dev_root;
1423 struct btrfs_key key;
1424 struct btrfs_key found_key;
1425 struct extent_buffer *leaf = NULL;
1426 struct btrfs_dev_extent *extent = NULL;
1427
1428 path = btrfs_alloc_path();
1429 if (!path)
1430 return -ENOMEM;
1431
1432 key.objectid = device->devid;
1433 key.offset = start;
1434 key.type = BTRFS_DEV_EXTENT_KEY;
1435 again:
1436 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1437 if (ret > 0) {
1438 ret = btrfs_previous_item(root, path, key.objectid,
1439 BTRFS_DEV_EXTENT_KEY);
1440 if (ret)
1441 goto out;
1442 leaf = path->nodes[0];
1443 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1444 extent = btrfs_item_ptr(leaf, path->slots[0],
1445 struct btrfs_dev_extent);
1446 BUG_ON(found_key.offset > start || found_key.offset +
1447 btrfs_dev_extent_length(leaf, extent) < start);
1448 key = found_key;
1449 btrfs_release_path(path);
1450 goto again;
1451 } else if (ret == 0) {
1452 leaf = path->nodes[0];
1453 extent = btrfs_item_ptr(leaf, path->slots[0],
1454 struct btrfs_dev_extent);
1455 } else {
1456 btrfs_std_error(root->fs_info, ret, "Slot search failed");
1457 goto out;
1458 }
1459
1460 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1461
1462 ret = btrfs_del_item(trans, root, path);
1463 if (ret) {
1464 btrfs_std_error(root->fs_info, ret,
1465 "Failed to remove dev extent item");
1466 } else {
1467 set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
1468 }
1469 out:
1470 btrfs_free_path(path);
1471 return ret;
1472 }
1473
1474 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1475 struct btrfs_device *device,
1476 u64 chunk_tree, u64 chunk_objectid,
1477 u64 chunk_offset, u64 start, u64 num_bytes)
1478 {
1479 int ret;
1480 struct btrfs_path *path;
1481 struct btrfs_root *root = device->dev_root;
1482 struct btrfs_dev_extent *extent;
1483 struct extent_buffer *leaf;
1484 struct btrfs_key key;
1485
1486 WARN_ON(!device->in_fs_metadata);
1487 WARN_ON(device->is_tgtdev_for_dev_replace);
1488 path = btrfs_alloc_path();
1489 if (!path)
1490 return -ENOMEM;
1491
1492 key.objectid = device->devid;
1493 key.offset = start;
1494 key.type = BTRFS_DEV_EXTENT_KEY;
1495 ret = btrfs_insert_empty_item(trans, root, path, &key,
1496 sizeof(*extent));
1497 if (ret)
1498 goto out;
1499
1500 leaf = path->nodes[0];
1501 extent = btrfs_item_ptr(leaf, path->slots[0],
1502 struct btrfs_dev_extent);
1503 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1504 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1505 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1506
1507 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1508 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE);
1509
1510 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1511 btrfs_mark_buffer_dirty(leaf);
1512 out:
1513 btrfs_free_path(path);
1514 return ret;
1515 }
1516
1517 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1518 {
1519 struct extent_map_tree *em_tree;
1520 struct extent_map *em;
1521 struct rb_node *n;
1522 u64 ret = 0;
1523
1524 em_tree = &fs_info->mapping_tree.map_tree;
1525 read_lock(&em_tree->lock);
1526 n = rb_last(&em_tree->map);
1527 if (n) {
1528 em = rb_entry(n, struct extent_map, rb_node);
1529 ret = em->start + em->len;
1530 }
1531 read_unlock(&em_tree->lock);
1532
1533 return ret;
1534 }
1535
1536 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1537 u64 *devid_ret)
1538 {
1539 int ret;
1540 struct btrfs_key key;
1541 struct btrfs_key found_key;
1542 struct btrfs_path *path;
1543
1544 path = btrfs_alloc_path();
1545 if (!path)
1546 return -ENOMEM;
1547
1548 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1549 key.type = BTRFS_DEV_ITEM_KEY;
1550 key.offset = (u64)-1;
1551
1552 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1553 if (ret < 0)
1554 goto error;
1555
1556 BUG_ON(ret == 0); /* Corruption */
1557
1558 ret = btrfs_previous_item(fs_info->chunk_root, path,
1559 BTRFS_DEV_ITEMS_OBJECTID,
1560 BTRFS_DEV_ITEM_KEY);
1561 if (ret) {
1562 *devid_ret = 1;
1563 } else {
1564 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1565 path->slots[0]);
1566 *devid_ret = found_key.offset + 1;
1567 }
1568 ret = 0;
1569 error:
1570 btrfs_free_path(path);
1571 return ret;
1572 }
1573
1574 /*
1575 * the device information is stored in the chunk root
1576 * the btrfs_device struct should be fully filled in
1577 */
1578 static int btrfs_add_device(struct btrfs_trans_handle *trans,
1579 struct btrfs_root *root,
1580 struct btrfs_device *device)
1581 {
1582 int ret;
1583 struct btrfs_path *path;
1584 struct btrfs_dev_item *dev_item;
1585 struct extent_buffer *leaf;
1586 struct btrfs_key key;
1587 unsigned long ptr;
1588
1589 root = root->fs_info->chunk_root;
1590
1591 path = btrfs_alloc_path();
1592 if (!path)
1593 return -ENOMEM;
1594
1595 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1596 key.type = BTRFS_DEV_ITEM_KEY;
1597 key.offset = device->devid;
1598
1599 ret = btrfs_insert_empty_item(trans, root, path, &key,
1600 sizeof(*dev_item));
1601 if (ret)
1602 goto out;
1603
1604 leaf = path->nodes[0];
1605 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1606
1607 btrfs_set_device_id(leaf, dev_item, device->devid);
1608 btrfs_set_device_generation(leaf, dev_item, 0);
1609 btrfs_set_device_type(leaf, dev_item, device->type);
1610 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1611 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1612 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1613 btrfs_set_device_total_bytes(leaf, dev_item,
1614 btrfs_device_get_disk_total_bytes(device));
1615 btrfs_set_device_bytes_used(leaf, dev_item,
1616 btrfs_device_get_bytes_used(device));
1617 btrfs_set_device_group(leaf, dev_item, 0);
1618 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1619 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1620 btrfs_set_device_start_offset(leaf, dev_item, 0);
1621
1622 ptr = btrfs_device_uuid(dev_item);
1623 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1624 ptr = btrfs_device_fsid(dev_item);
1625 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1626 btrfs_mark_buffer_dirty(leaf);
1627
1628 ret = 0;
1629 out:
1630 btrfs_free_path(path);
1631 return ret;
1632 }
1633
1634 /*
1635 * Function to update ctime/mtime for a given device path.
1636 * Mainly used for ctime/mtime based probe like libblkid.
1637 */
1638 static void update_dev_time(char *path_name)
1639 {
1640 struct file *filp;
1641
1642 filp = filp_open(path_name, O_RDWR, 0);
1643 if (IS_ERR(filp))
1644 return;
1645 file_update_time(filp);
1646 filp_close(filp, NULL);
1647 return;
1648 }
1649
1650 static int btrfs_rm_dev_item(struct btrfs_root *root,
1651 struct btrfs_device *device)
1652 {
1653 int ret;
1654 struct btrfs_path *path;
1655 struct btrfs_key key;
1656 struct btrfs_trans_handle *trans;
1657
1658 root = root->fs_info->chunk_root;
1659
1660 path = btrfs_alloc_path();
1661 if (!path)
1662 return -ENOMEM;
1663
1664 trans = btrfs_start_transaction(root, 0);
1665 if (IS_ERR(trans)) {
1666 btrfs_free_path(path);
1667 return PTR_ERR(trans);
1668 }
1669 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1670 key.type = BTRFS_DEV_ITEM_KEY;
1671 key.offset = device->devid;
1672
1673 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1674 if (ret < 0)
1675 goto out;
1676
1677 if (ret > 0) {
1678 ret = -ENOENT;
1679 goto out;
1680 }
1681
1682 ret = btrfs_del_item(trans, root, path);
1683 if (ret)
1684 goto out;
1685 out:
1686 btrfs_free_path(path);
1687 btrfs_commit_transaction(trans, root);
1688 return ret;
1689 }
1690
1691 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1692 {
1693 struct btrfs_device *device;
1694 struct btrfs_device *next_device;
1695 struct block_device *bdev;
1696 struct buffer_head *bh = NULL;
1697 struct btrfs_super_block *disk_super;
1698 struct btrfs_fs_devices *cur_devices;
1699 u64 all_avail;
1700 u64 devid;
1701 u64 num_devices;
1702 u8 *dev_uuid;
1703 unsigned seq;
1704 int ret = 0;
1705 bool clear_super = false;
1706
1707 mutex_lock(&uuid_mutex);
1708
1709 do {
1710 seq = read_seqbegin(&root->fs_info->profiles_lock);
1711
1712 all_avail = root->fs_info->avail_data_alloc_bits |
1713 root->fs_info->avail_system_alloc_bits |
1714 root->fs_info->avail_metadata_alloc_bits;
1715 } while (read_seqretry(&root->fs_info->profiles_lock, seq));
1716
1717 num_devices = root->fs_info->fs_devices->num_devices;
1718 btrfs_dev_replace_lock(&root->fs_info->dev_replace);
1719 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1720 WARN_ON(num_devices < 1);
1721 num_devices--;
1722 }
1723 btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
1724
1725 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
1726 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
1727 goto out;
1728 }
1729
1730 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
1731 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
1732 goto out;
1733 }
1734
1735 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
1736 root->fs_info->fs_devices->rw_devices <= 2) {
1737 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
1738 goto out;
1739 }
1740 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
1741 root->fs_info->fs_devices->rw_devices <= 3) {
1742 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
1743 goto out;
1744 }
1745
1746 if (strcmp(device_path, "missing") == 0) {
1747 struct list_head *devices;
1748 struct btrfs_device *tmp;
1749
1750 device = NULL;
1751 devices = &root->fs_info->fs_devices->devices;
1752 /*
1753 * It is safe to read the devices since the volume_mutex
1754 * is held.
1755 */
1756 list_for_each_entry(tmp, devices, dev_list) {
1757 if (tmp->in_fs_metadata &&
1758 !tmp->is_tgtdev_for_dev_replace &&
1759 !tmp->bdev) {
1760 device = tmp;
1761 break;
1762 }
1763 }
1764 bdev = NULL;
1765 bh = NULL;
1766 disk_super = NULL;
1767 if (!device) {
1768 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
1769 goto out;
1770 }
1771 } else {
1772 ret = btrfs_get_bdev_and_sb(device_path,
1773 FMODE_WRITE | FMODE_EXCL,
1774 root->fs_info->bdev_holder, 0,
1775 &bdev, &bh);
1776 if (ret)
1777 goto out;
1778 disk_super = (struct btrfs_super_block *)bh->b_data;
1779 devid = btrfs_stack_device_id(&disk_super->dev_item);
1780 dev_uuid = disk_super->dev_item.uuid;
1781 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1782 disk_super->fsid);
1783 if (!device) {
1784 ret = -ENOENT;
1785 goto error_brelse;
1786 }
1787 }
1788
1789 if (device->is_tgtdev_for_dev_replace) {
1790 ret = BTRFS_ERROR_DEV_TGT_REPLACE;
1791 goto error_brelse;
1792 }
1793
1794 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1795 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
1796 goto error_brelse;
1797 }
1798
1799 if (device->writeable) {
1800 lock_chunks(root);
1801 list_del_init(&device->dev_alloc_list);
1802 device->fs_devices->rw_devices--;
1803 unlock_chunks(root);
1804 clear_super = true;
1805 }
1806
1807 mutex_unlock(&uuid_mutex);
1808 ret = btrfs_shrink_device(device, 0);
1809 mutex_lock(&uuid_mutex);
1810 if (ret)
1811 goto error_undo;
1812
1813 /*
1814 * TODO: the superblock still includes this device in its num_devices
1815 * counter although write_all_supers() is not locked out. This
1816 * could give a filesystem state which requires a degraded mount.
1817 */
1818 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1819 if (ret)
1820 goto error_undo;
1821
1822 device->in_fs_metadata = 0;
1823 btrfs_scrub_cancel_dev(root->fs_info, device);
1824
1825 /*
1826 * the device list mutex makes sure that we don't change
1827 * the device list while someone else is writing out all
1828 * the device supers. Whoever is writing all supers, should
1829 * lock the device list mutex before getting the number of
1830 * devices in the super block (super_copy). Conversely,
1831 * whoever updates the number of devices in the super block
1832 * (super_copy) should hold the device list mutex.
1833 */
1834
1835 cur_devices = device->fs_devices;
1836 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1837 list_del_rcu(&device->dev_list);
1838
1839 device->fs_devices->num_devices--;
1840 device->fs_devices->total_devices--;
1841
1842 if (device->missing)
1843 device->fs_devices->missing_devices--;
1844
1845 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1846 struct btrfs_device, dev_list);
1847 if (device->bdev == root->fs_info->sb->s_bdev)
1848 root->fs_info->sb->s_bdev = next_device->bdev;
1849 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1850 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1851
1852 if (device->bdev) {
1853 device->fs_devices->open_devices--;
1854 /* remove sysfs entry */
1855 btrfs_sysfs_rm_device_link(root->fs_info->fs_devices, device);
1856 }
1857
1858 call_rcu(&device->rcu, free_device);
1859
1860 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1861 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1862 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1863
1864 if (cur_devices->open_devices == 0) {
1865 struct btrfs_fs_devices *fs_devices;
1866 fs_devices = root->fs_info->fs_devices;
1867 while (fs_devices) {
1868 if (fs_devices->seed == cur_devices) {
1869 fs_devices->seed = cur_devices->seed;
1870 break;
1871 }
1872 fs_devices = fs_devices->seed;
1873 }
1874 cur_devices->seed = NULL;
1875 __btrfs_close_devices(cur_devices);
1876 free_fs_devices(cur_devices);
1877 }
1878
1879 root->fs_info->num_tolerated_disk_barrier_failures =
1880 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1881
1882 /*
1883 * at this point, the device is zero sized. We want to
1884 * remove it from the devices list and zero out the old super
1885 */
1886 if (clear_super && disk_super) {
1887 u64 bytenr;
1888 int i;
1889
1890 /* make sure this device isn't detected as part of
1891 * the FS anymore
1892 */
1893 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1894 set_buffer_dirty(bh);
1895 sync_dirty_buffer(bh);
1896
1897 /* clear the mirror copies of super block on the disk
1898 * being removed, 0th copy is been taken care above and
1899 * the below would take of the rest
1900 */
1901 for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1902 bytenr = btrfs_sb_offset(i);
1903 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
1904 i_size_read(bdev->bd_inode))
1905 break;
1906
1907 brelse(bh);
1908 bh = __bread(bdev, bytenr / 4096,
1909 BTRFS_SUPER_INFO_SIZE);
1910 if (!bh)
1911 continue;
1912
1913 disk_super = (struct btrfs_super_block *)bh->b_data;
1914
1915 if (btrfs_super_bytenr(disk_super) != bytenr ||
1916 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1917 continue;
1918 }
1919 memset(&disk_super->magic, 0,
1920 sizeof(disk_super->magic));
1921 set_buffer_dirty(bh);
1922 sync_dirty_buffer(bh);
1923 }
1924 }
1925
1926 ret = 0;
1927
1928 if (bdev) {
1929 /* Notify udev that device has changed */
1930 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
1931
1932 /* Update ctime/mtime for device path for libblkid */
1933 update_dev_time(device_path);
1934 }
1935
1936 error_brelse:
1937 brelse(bh);
1938 if (bdev)
1939 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1940 out:
1941 mutex_unlock(&uuid_mutex);
1942 return ret;
1943 error_undo:
1944 if (device->writeable) {
1945 lock_chunks(root);
1946 list_add(&device->dev_alloc_list,
1947 &root->fs_info->fs_devices->alloc_list);
1948 device->fs_devices->rw_devices++;
1949 unlock_chunks(root);
1950 }
1951 goto error_brelse;
1952 }
1953
1954 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
1955 struct btrfs_device *srcdev)
1956 {
1957 struct btrfs_fs_devices *fs_devices;
1958
1959 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1960
1961 /*
1962 * in case of fs with no seed, srcdev->fs_devices will point
1963 * to fs_devices of fs_info. However when the dev being replaced is
1964 * a seed dev it will point to the seed's local fs_devices. In short
1965 * srcdev will have its correct fs_devices in both the cases.
1966 */
1967 fs_devices = srcdev->fs_devices;
1968
1969 list_del_rcu(&srcdev->dev_list);
1970 list_del_rcu(&srcdev->dev_alloc_list);
1971 fs_devices->num_devices--;
1972 if (srcdev->missing)
1973 fs_devices->missing_devices--;
1974
1975 if (srcdev->writeable) {
1976 fs_devices->rw_devices--;
1977 /* zero out the old super if it is writable */
1978 btrfs_scratch_superblocks(srcdev->bdev, srcdev->name->str);
1979 }
1980
1981 if (srcdev->bdev)
1982 fs_devices->open_devices--;
1983 }
1984
1985 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
1986 struct btrfs_device *srcdev)
1987 {
1988 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
1989
1990 call_rcu(&srcdev->rcu, free_device);
1991
1992 /*
1993 * unless fs_devices is seed fs, num_devices shouldn't go
1994 * zero
1995 */
1996 BUG_ON(!fs_devices->num_devices && !fs_devices->seeding);
1997
1998 /* if this is no devs we rather delete the fs_devices */
1999 if (!fs_devices->num_devices) {
2000 struct btrfs_fs_devices *tmp_fs_devices;
2001
2002 tmp_fs_devices = fs_info->fs_devices;
2003 while (tmp_fs_devices) {
2004 if (tmp_fs_devices->seed == fs_devices) {
2005 tmp_fs_devices->seed = fs_devices->seed;
2006 break;
2007 }
2008 tmp_fs_devices = tmp_fs_devices->seed;
2009 }
2010 fs_devices->seed = NULL;
2011 __btrfs_close_devices(fs_devices);
2012 free_fs_devices(fs_devices);
2013 }
2014 }
2015
2016 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
2017 struct btrfs_device *tgtdev)
2018 {
2019 struct btrfs_device *next_device;
2020
2021 mutex_lock(&uuid_mutex);
2022 WARN_ON(!tgtdev);
2023 mutex_lock(&fs_info->fs_devices->device_list_mutex);
2024
2025 btrfs_sysfs_rm_device_link(fs_info->fs_devices, tgtdev);
2026
2027 if (tgtdev->bdev) {
2028 btrfs_scratch_superblocks(tgtdev->bdev, tgtdev->name->str);
2029 fs_info->fs_devices->open_devices--;
2030 }
2031 fs_info->fs_devices->num_devices--;
2032
2033 next_device = list_entry(fs_info->fs_devices->devices.next,
2034 struct btrfs_device, dev_list);
2035 if (tgtdev->bdev == fs_info->sb->s_bdev)
2036 fs_info->sb->s_bdev = next_device->bdev;
2037 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
2038 fs_info->fs_devices->latest_bdev = next_device->bdev;
2039 list_del_rcu(&tgtdev->dev_list);
2040
2041 call_rcu(&tgtdev->rcu, free_device);
2042
2043 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2044 mutex_unlock(&uuid_mutex);
2045 }
2046
2047 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
2048 struct btrfs_device **device)
2049 {
2050 int ret = 0;
2051 struct btrfs_super_block *disk_super;
2052 u64 devid;
2053 u8 *dev_uuid;
2054 struct block_device *bdev;
2055 struct buffer_head *bh;
2056
2057 *device = NULL;
2058 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ,
2059 root->fs_info->bdev_holder, 0, &bdev, &bh);
2060 if (ret)
2061 return ret;
2062 disk_super = (struct btrfs_super_block *)bh->b_data;
2063 devid = btrfs_stack_device_id(&disk_super->dev_item);
2064 dev_uuid = disk_super->dev_item.uuid;
2065 *device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2066 disk_super->fsid);
2067 brelse(bh);
2068 if (!*device)
2069 ret = -ENOENT;
2070 blkdev_put(bdev, FMODE_READ);
2071 return ret;
2072 }
2073
2074 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
2075 char *device_path,
2076 struct btrfs_device **device)
2077 {
2078 *device = NULL;
2079 if (strcmp(device_path, "missing") == 0) {
2080 struct list_head *devices;
2081 struct btrfs_device *tmp;
2082
2083 devices = &root->fs_info->fs_devices->devices;
2084 /*
2085 * It is safe to read the devices since the volume_mutex
2086 * is held by the caller.
2087 */
2088 list_for_each_entry(tmp, devices, dev_list) {
2089 if (tmp->in_fs_metadata && !tmp->bdev) {
2090 *device = tmp;
2091 break;
2092 }
2093 }
2094
2095 if (!*device)
2096 return BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
2097
2098 return 0;
2099 } else {
2100 return btrfs_find_device_by_path(root, device_path, device);
2101 }
2102 }
2103
2104 /*
2105 * does all the dirty work required for changing file system's UUID.
2106 */
2107 static int btrfs_prepare_sprout(struct btrfs_root *root)
2108 {
2109 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2110 struct btrfs_fs_devices *old_devices;
2111 struct btrfs_fs_devices *seed_devices;
2112 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
2113 struct btrfs_device *device;
2114 u64 super_flags;
2115
2116 BUG_ON(!mutex_is_locked(&uuid_mutex));
2117 if (!fs_devices->seeding)
2118 return -EINVAL;
2119
2120 seed_devices = __alloc_fs_devices();
2121 if (IS_ERR(seed_devices))
2122 return PTR_ERR(seed_devices);
2123
2124 old_devices = clone_fs_devices(fs_devices);
2125 if (IS_ERR(old_devices)) {
2126 kfree(seed_devices);
2127 return PTR_ERR(old_devices);
2128 }
2129
2130 list_add(&old_devices->list, &fs_uuids);
2131
2132 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
2133 seed_devices->opened = 1;
2134 INIT_LIST_HEAD(&seed_devices->devices);
2135 INIT_LIST_HEAD(&seed_devices->alloc_list);
2136 mutex_init(&seed_devices->device_list_mutex);
2137
2138 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2139 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
2140 synchronize_rcu);
2141 list_for_each_entry(device, &seed_devices->devices, dev_list)
2142 device->fs_devices = seed_devices;
2143
2144 lock_chunks(root);
2145 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
2146 unlock_chunks(root);
2147
2148 fs_devices->seeding = 0;
2149 fs_devices->num_devices = 0;
2150 fs_devices->open_devices = 0;
2151 fs_devices->missing_devices = 0;
2152 fs_devices->rotating = 0;
2153 fs_devices->seed = seed_devices;
2154
2155 generate_random_uuid(fs_devices->fsid);
2156 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2157 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2158 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2159
2160 super_flags = btrfs_super_flags(disk_super) &
2161 ~BTRFS_SUPER_FLAG_SEEDING;
2162 btrfs_set_super_flags(disk_super, super_flags);
2163
2164 return 0;
2165 }
2166
2167 /*
2168 * strore the expected generation for seed devices in device items.
2169 */
2170 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
2171 struct btrfs_root *root)
2172 {
2173 struct btrfs_path *path;
2174 struct extent_buffer *leaf;
2175 struct btrfs_dev_item *dev_item;
2176 struct btrfs_device *device;
2177 struct btrfs_key key;
2178 u8 fs_uuid[BTRFS_UUID_SIZE];
2179 u8 dev_uuid[BTRFS_UUID_SIZE];
2180 u64 devid;
2181 int ret;
2182
2183 path = btrfs_alloc_path();
2184 if (!path)
2185 return -ENOMEM;
2186
2187 root = root->fs_info->chunk_root;
2188 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2189 key.offset = 0;
2190 key.type = BTRFS_DEV_ITEM_KEY;
2191
2192 while (1) {
2193 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2194 if (ret < 0)
2195 goto error;
2196
2197 leaf = path->nodes[0];
2198 next_slot:
2199 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2200 ret = btrfs_next_leaf(root, path);
2201 if (ret > 0)
2202 break;
2203 if (ret < 0)
2204 goto error;
2205 leaf = path->nodes[0];
2206 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2207 btrfs_release_path(path);
2208 continue;
2209 }
2210
2211 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2212 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2213 key.type != BTRFS_DEV_ITEM_KEY)
2214 break;
2215
2216 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2217 struct btrfs_dev_item);
2218 devid = btrfs_device_id(leaf, dev_item);
2219 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2220 BTRFS_UUID_SIZE);
2221 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2222 BTRFS_UUID_SIZE);
2223 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2224 fs_uuid);
2225 BUG_ON(!device); /* Logic error */
2226
2227 if (device->fs_devices->seeding) {
2228 btrfs_set_device_generation(leaf, dev_item,
2229 device->generation);
2230 btrfs_mark_buffer_dirty(leaf);
2231 }
2232
2233 path->slots[0]++;
2234 goto next_slot;
2235 }
2236 ret = 0;
2237 error:
2238 btrfs_free_path(path);
2239 return ret;
2240 }
2241
2242 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
2243 {
2244 struct request_queue *q;
2245 struct btrfs_trans_handle *trans;
2246 struct btrfs_device *device;
2247 struct block_device *bdev;
2248 struct list_head *devices;
2249 struct super_block *sb = root->fs_info->sb;
2250 struct rcu_string *name;
2251 u64 tmp;
2252 int seeding_dev = 0;
2253 int ret = 0;
2254
2255 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
2256 return -EROFS;
2257
2258 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2259 root->fs_info->bdev_holder);
2260 if (IS_ERR(bdev))
2261 return PTR_ERR(bdev);
2262
2263 if (root->fs_info->fs_devices->seeding) {
2264 seeding_dev = 1;
2265 down_write(&sb->s_umount);
2266 mutex_lock(&uuid_mutex);
2267 }
2268
2269 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2270
2271 devices = &root->fs_info->fs_devices->devices;
2272
2273 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2274 list_for_each_entry(device, devices, dev_list) {
2275 if (device->bdev == bdev) {
2276 ret = -EEXIST;
2277 mutex_unlock(
2278 &root->fs_info->fs_devices->device_list_mutex);
2279 goto error;
2280 }
2281 }
2282 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2283
2284 device = btrfs_alloc_device(root->fs_info, NULL, NULL);
2285 if (IS_ERR(device)) {
2286 /* we can safely leave the fs_devices entry around */
2287 ret = PTR_ERR(device);
2288 goto error;
2289 }
2290
2291 name = rcu_string_strdup(device_path, GFP_NOFS);
2292 if (!name) {
2293 kfree(device);
2294 ret = -ENOMEM;
2295 goto error;
2296 }
2297 rcu_assign_pointer(device->name, name);
2298
2299 trans = btrfs_start_transaction(root, 0);
2300 if (IS_ERR(trans)) {
2301 rcu_string_free(device->name);
2302 kfree(device);
2303 ret = PTR_ERR(trans);
2304 goto error;
2305 }
2306
2307 q = bdev_get_queue(bdev);
2308 if (blk_queue_discard(q))
2309 device->can_discard = 1;
2310 device->writeable = 1;
2311 device->generation = trans->transid;
2312 device->io_width = root->sectorsize;
2313 device->io_align = root->sectorsize;
2314 device->sector_size = root->sectorsize;
2315 device->total_bytes = i_size_read(bdev->bd_inode);
2316 device->disk_total_bytes = device->total_bytes;
2317 device->commit_total_bytes = device->total_bytes;
2318 device->dev_root = root->fs_info->dev_root;
2319 device->bdev = bdev;
2320 device->in_fs_metadata = 1;
2321 device->is_tgtdev_for_dev_replace = 0;
2322 device->mode = FMODE_EXCL;
2323 device->dev_stats_valid = 1;
2324 set_blocksize(device->bdev, 4096);
2325
2326 if (seeding_dev) {
2327 sb->s_flags &= ~MS_RDONLY;
2328 ret = btrfs_prepare_sprout(root);
2329 BUG_ON(ret); /* -ENOMEM */
2330 }
2331
2332 device->fs_devices = root->fs_info->fs_devices;
2333
2334 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2335 lock_chunks(root);
2336 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
2337 list_add(&device->dev_alloc_list,
2338 &root->fs_info->fs_devices->alloc_list);
2339 root->fs_info->fs_devices->num_devices++;
2340 root->fs_info->fs_devices->open_devices++;
2341 root->fs_info->fs_devices->rw_devices++;
2342 root->fs_info->fs_devices->total_devices++;
2343 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
2344
2345 spin_lock(&root->fs_info->free_chunk_lock);
2346 root->fs_info->free_chunk_space += device->total_bytes;
2347 spin_unlock(&root->fs_info->free_chunk_lock);
2348
2349 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
2350 root->fs_info->fs_devices->rotating = 1;
2351
2352 tmp = btrfs_super_total_bytes(root->fs_info->super_copy);
2353 btrfs_set_super_total_bytes(root->fs_info->super_copy,
2354 tmp + device->total_bytes);
2355
2356 tmp = btrfs_super_num_devices(root->fs_info->super_copy);
2357 btrfs_set_super_num_devices(root->fs_info->super_copy,
2358 tmp + 1);
2359
2360 /* add sysfs device entry */
2361 btrfs_sysfs_add_device_link(root->fs_info->fs_devices, device);
2362
2363 /*
2364 * we've got more storage, clear any full flags on the space
2365 * infos
2366 */
2367 btrfs_clear_space_info_full(root->fs_info);
2368
2369 unlock_chunks(root);
2370 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2371
2372 if (seeding_dev) {
2373 lock_chunks(root);
2374 ret = init_first_rw_device(trans, root, device);
2375 unlock_chunks(root);
2376 if (ret) {
2377 btrfs_abort_transaction(trans, root, ret);
2378 goto error_trans;
2379 }
2380 }
2381
2382 ret = btrfs_add_device(trans, root, device);
2383 if (ret) {
2384 btrfs_abort_transaction(trans, root, ret);
2385 goto error_trans;
2386 }
2387
2388 if (seeding_dev) {
2389 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2390
2391 ret = btrfs_finish_sprout(trans, root);
2392 if (ret) {
2393 btrfs_abort_transaction(trans, root, ret);
2394 goto error_trans;
2395 }
2396
2397 /* Sprouting would change fsid of the mounted root,
2398 * so rename the fsid on the sysfs
2399 */
2400 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU",
2401 root->fs_info->fsid);
2402 if (kobject_rename(&root->fs_info->fs_devices->fsid_kobj,
2403 fsid_buf))
2404 btrfs_warn(root->fs_info,
2405 "sysfs: failed to create fsid for sprout");
2406 }
2407
2408 root->fs_info->num_tolerated_disk_barrier_failures =
2409 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2410 ret = btrfs_commit_transaction(trans, root);
2411
2412 if (seeding_dev) {
2413 mutex_unlock(&uuid_mutex);
2414 up_write(&sb->s_umount);
2415
2416 if (ret) /* transaction commit */
2417 return ret;
2418
2419 ret = btrfs_relocate_sys_chunks(root);
2420 if (ret < 0)
2421 btrfs_std_error(root->fs_info, ret,
2422 "Failed to relocate sys chunks after "
2423 "device initialization. This can be fixed "
2424 "using the \"btrfs balance\" command.");
2425 trans = btrfs_attach_transaction(root);
2426 if (IS_ERR(trans)) {
2427 if (PTR_ERR(trans) == -ENOENT)
2428 return 0;
2429 return PTR_ERR(trans);
2430 }
2431 ret = btrfs_commit_transaction(trans, root);
2432 }
2433
2434 /* Update ctime/mtime for libblkid */
2435 update_dev_time(device_path);
2436 return ret;
2437
2438 error_trans:
2439 btrfs_end_transaction(trans, root);
2440 rcu_string_free(device->name);
2441 btrfs_sysfs_rm_device_link(root->fs_info->fs_devices, device);
2442 kfree(device);
2443 error:
2444 blkdev_put(bdev, FMODE_EXCL);
2445 if (seeding_dev) {
2446 mutex_unlock(&uuid_mutex);
2447 up_write(&sb->s_umount);
2448 }
2449 return ret;
2450 }
2451
2452 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2453 struct btrfs_device *srcdev,
2454 struct btrfs_device **device_out)
2455 {
2456 struct request_queue *q;
2457 struct btrfs_device *device;
2458 struct block_device *bdev;
2459 struct btrfs_fs_info *fs_info = root->fs_info;
2460 struct list_head *devices;
2461 struct rcu_string *name;
2462 u64 devid = BTRFS_DEV_REPLACE_DEVID;
2463 int ret = 0;
2464
2465 *device_out = NULL;
2466 if (fs_info->fs_devices->seeding) {
2467 btrfs_err(fs_info, "the filesystem is a seed filesystem!");
2468 return -EINVAL;
2469 }
2470
2471 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2472 fs_info->bdev_holder);
2473 if (IS_ERR(bdev)) {
2474 btrfs_err(fs_info, "target device %s is invalid!", device_path);
2475 return PTR_ERR(bdev);
2476 }
2477
2478 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2479
2480 devices = &fs_info->fs_devices->devices;
2481 list_for_each_entry(device, devices, dev_list) {
2482 if (device->bdev == bdev) {
2483 btrfs_err(fs_info, "target device is in the filesystem!");
2484 ret = -EEXIST;
2485 goto error;
2486 }
2487 }
2488
2489
2490 if (i_size_read(bdev->bd_inode) <
2491 btrfs_device_get_total_bytes(srcdev)) {
2492 btrfs_err(fs_info, "target device is smaller than source device!");
2493 ret = -EINVAL;
2494 goto error;
2495 }
2496
2497
2498 device = btrfs_alloc_device(NULL, &devid, NULL);
2499 if (IS_ERR(device)) {
2500 ret = PTR_ERR(device);
2501 goto error;
2502 }
2503
2504 name = rcu_string_strdup(device_path, GFP_NOFS);
2505 if (!name) {
2506 kfree(device);
2507 ret = -ENOMEM;
2508 goto error;
2509 }
2510 rcu_assign_pointer(device->name, name);
2511
2512 q = bdev_get_queue(bdev);
2513 if (blk_queue_discard(q))
2514 device->can_discard = 1;
2515 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2516 device->writeable = 1;
2517 device->generation = 0;
2518 device->io_width = root->sectorsize;
2519 device->io_align = root->sectorsize;
2520 device->sector_size = root->sectorsize;
2521 device->total_bytes = btrfs_device_get_total_bytes(srcdev);
2522 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev);
2523 device->bytes_used = btrfs_device_get_bytes_used(srcdev);
2524 ASSERT(list_empty(&srcdev->resized_list));
2525 device->commit_total_bytes = srcdev->commit_total_bytes;
2526 device->commit_bytes_used = device->bytes_used;
2527 device->dev_root = fs_info->dev_root;
2528 device->bdev = bdev;
2529 device->in_fs_metadata = 1;
2530 device->is_tgtdev_for_dev_replace = 1;
2531 device->mode = FMODE_EXCL;
2532 device->dev_stats_valid = 1;
2533 set_blocksize(device->bdev, 4096);
2534 device->fs_devices = fs_info->fs_devices;
2535 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2536 fs_info->fs_devices->num_devices++;
2537 fs_info->fs_devices->open_devices++;
2538 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2539
2540 *device_out = device;
2541 return ret;
2542
2543 error:
2544 blkdev_put(bdev, FMODE_EXCL);
2545 return ret;
2546 }
2547
2548 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2549 struct btrfs_device *tgtdev)
2550 {
2551 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2552 tgtdev->io_width = fs_info->dev_root->sectorsize;
2553 tgtdev->io_align = fs_info->dev_root->sectorsize;
2554 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2555 tgtdev->dev_root = fs_info->dev_root;
2556 tgtdev->in_fs_metadata = 1;
2557 }
2558
2559 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2560 struct btrfs_device *device)
2561 {
2562 int ret;
2563 struct btrfs_path *path;
2564 struct btrfs_root *root;
2565 struct btrfs_dev_item *dev_item;
2566 struct extent_buffer *leaf;
2567 struct btrfs_key key;
2568
2569 root = device->dev_root->fs_info->chunk_root;
2570
2571 path = btrfs_alloc_path();
2572 if (!path)
2573 return -ENOMEM;
2574
2575 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2576 key.type = BTRFS_DEV_ITEM_KEY;
2577 key.offset = device->devid;
2578
2579 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2580 if (ret < 0)
2581 goto out;
2582
2583 if (ret > 0) {
2584 ret = -ENOENT;
2585 goto out;
2586 }
2587
2588 leaf = path->nodes[0];
2589 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2590
2591 btrfs_set_device_id(leaf, dev_item, device->devid);
2592 btrfs_set_device_type(leaf, dev_item, device->type);
2593 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2594 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2595 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2596 btrfs_set_device_total_bytes(leaf, dev_item,
2597 btrfs_device_get_disk_total_bytes(device));
2598 btrfs_set_device_bytes_used(leaf, dev_item,
2599 btrfs_device_get_bytes_used(device));
2600 btrfs_mark_buffer_dirty(leaf);
2601
2602 out:
2603 btrfs_free_path(path);
2604 return ret;
2605 }
2606
2607 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2608 struct btrfs_device *device, u64 new_size)
2609 {
2610 struct btrfs_super_block *super_copy =
2611 device->dev_root->fs_info->super_copy;
2612 struct btrfs_fs_devices *fs_devices;
2613 u64 old_total;
2614 u64 diff;
2615
2616 if (!device->writeable)
2617 return -EACCES;
2618
2619 lock_chunks(device->dev_root);
2620 old_total = btrfs_super_total_bytes(super_copy);
2621 diff = new_size - device->total_bytes;
2622
2623 if (new_size <= device->total_bytes ||
2624 device->is_tgtdev_for_dev_replace) {
2625 unlock_chunks(device->dev_root);
2626 return -EINVAL;
2627 }
2628
2629 fs_devices = device->dev_root->fs_info->fs_devices;
2630
2631 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2632 device->fs_devices->total_rw_bytes += diff;
2633
2634 btrfs_device_set_total_bytes(device, new_size);
2635 btrfs_device_set_disk_total_bytes(device, new_size);
2636 btrfs_clear_space_info_full(device->dev_root->fs_info);
2637 if (list_empty(&device->resized_list))
2638 list_add_tail(&device->resized_list,
2639 &fs_devices->resized_devices);
2640 unlock_chunks(device->dev_root);
2641
2642 return btrfs_update_device(trans, device);
2643 }
2644
2645 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2646 struct btrfs_root *root, u64 chunk_objectid,
2647 u64 chunk_offset)
2648 {
2649 int ret;
2650 struct btrfs_path *path;
2651 struct btrfs_key key;
2652
2653 root = root->fs_info->chunk_root;
2654 path = btrfs_alloc_path();
2655 if (!path)
2656 return -ENOMEM;
2657
2658 key.objectid = chunk_objectid;
2659 key.offset = chunk_offset;
2660 key.type = BTRFS_CHUNK_ITEM_KEY;
2661
2662 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2663 if (ret < 0)
2664 goto out;
2665 else if (ret > 0) { /* Logic error or corruption */
2666 btrfs_std_error(root->fs_info, -ENOENT,
2667 "Failed lookup while freeing chunk.");
2668 ret = -ENOENT;
2669 goto out;
2670 }
2671
2672 ret = btrfs_del_item(trans, root, path);
2673 if (ret < 0)
2674 btrfs_std_error(root->fs_info, ret,
2675 "Failed to delete chunk item.");
2676 out:
2677 btrfs_free_path(path);
2678 return ret;
2679 }
2680
2681 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2682 chunk_offset)
2683 {
2684 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2685 struct btrfs_disk_key *disk_key;
2686 struct btrfs_chunk *chunk;
2687 u8 *ptr;
2688 int ret = 0;
2689 u32 num_stripes;
2690 u32 array_size;
2691 u32 len = 0;
2692 u32 cur;
2693 struct btrfs_key key;
2694
2695 lock_chunks(root);
2696 array_size = btrfs_super_sys_array_size(super_copy);
2697
2698 ptr = super_copy->sys_chunk_array;
2699 cur = 0;
2700
2701 while (cur < array_size) {
2702 disk_key = (struct btrfs_disk_key *)ptr;
2703 btrfs_disk_key_to_cpu(&key, disk_key);
2704
2705 len = sizeof(*disk_key);
2706
2707 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2708 chunk = (struct btrfs_chunk *)(ptr + len);
2709 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2710 len += btrfs_chunk_item_size(num_stripes);
2711 } else {
2712 ret = -EIO;
2713 break;
2714 }
2715 if (key.objectid == chunk_objectid &&
2716 key.offset == chunk_offset) {
2717 memmove(ptr, ptr + len, array_size - (cur + len));
2718 array_size -= len;
2719 btrfs_set_super_sys_array_size(super_copy, array_size);
2720 } else {
2721 ptr += len;
2722 cur += len;
2723 }
2724 }
2725 unlock_chunks(root);
2726 return ret;
2727 }
2728
2729 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
2730 struct btrfs_root *root, u64 chunk_offset)
2731 {
2732 struct extent_map_tree *em_tree;
2733 struct extent_map *em;
2734 struct btrfs_root *extent_root = root->fs_info->extent_root;
2735 struct map_lookup *map;
2736 u64 dev_extent_len = 0;
2737 u64 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2738 int i, ret = 0;
2739
2740 /* Just in case */
2741 root = root->fs_info->chunk_root;
2742 em_tree = &root->fs_info->mapping_tree.map_tree;
2743
2744 read_lock(&em_tree->lock);
2745 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2746 read_unlock(&em_tree->lock);
2747
2748 if (!em || em->start > chunk_offset ||
2749 em->start + em->len < chunk_offset) {
2750 /*
2751 * This is a logic error, but we don't want to just rely on the
2752 * user having built with ASSERT enabled, so if ASSERT doens't
2753 * do anything we still error out.
2754 */
2755 ASSERT(0);
2756 if (em)
2757 free_extent_map(em);
2758 return -EINVAL;
2759 }
2760 map = (struct map_lookup *)em->bdev;
2761 lock_chunks(root->fs_info->chunk_root);
2762 check_system_chunk(trans, extent_root, map->type);
2763 unlock_chunks(root->fs_info->chunk_root);
2764
2765 for (i = 0; i < map->num_stripes; i++) {
2766 struct btrfs_device *device = map->stripes[i].dev;
2767 ret = btrfs_free_dev_extent(trans, device,
2768 map->stripes[i].physical,
2769 &dev_extent_len);
2770 if (ret) {
2771 btrfs_abort_transaction(trans, root, ret);
2772 goto out;
2773 }
2774
2775 if (device->bytes_used > 0) {
2776 lock_chunks(root);
2777 btrfs_device_set_bytes_used(device,
2778 device->bytes_used - dev_extent_len);
2779 spin_lock(&root->fs_info->free_chunk_lock);
2780 root->fs_info->free_chunk_space += dev_extent_len;
2781 spin_unlock(&root->fs_info->free_chunk_lock);
2782 btrfs_clear_space_info_full(root->fs_info);
2783 unlock_chunks(root);
2784 }
2785
2786 if (map->stripes[i].dev) {
2787 ret = btrfs_update_device(trans, map->stripes[i].dev);
2788 if (ret) {
2789 btrfs_abort_transaction(trans, root, ret);
2790 goto out;
2791 }
2792 }
2793 }
2794 ret = btrfs_free_chunk(trans, root, chunk_objectid, chunk_offset);
2795 if (ret) {
2796 btrfs_abort_transaction(trans, root, ret);
2797 goto out;
2798 }
2799
2800 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2801
2802 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2803 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2804 if (ret) {
2805 btrfs_abort_transaction(trans, root, ret);
2806 goto out;
2807 }
2808 }
2809
2810 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset, em);
2811 if (ret) {
2812 btrfs_abort_transaction(trans, extent_root, ret);
2813 goto out;
2814 }
2815
2816 out:
2817 /* once for us */
2818 free_extent_map(em);
2819 return ret;
2820 }
2821
2822 static int btrfs_relocate_chunk(struct btrfs_root *root, u64 chunk_offset)
2823 {
2824 struct btrfs_root *extent_root;
2825 struct btrfs_trans_handle *trans;
2826 int ret;
2827
2828 root = root->fs_info->chunk_root;
2829 extent_root = root->fs_info->extent_root;
2830
2831 /*
2832 * Prevent races with automatic removal of unused block groups.
2833 * After we relocate and before we remove the chunk with offset
2834 * chunk_offset, automatic removal of the block group can kick in,
2835 * resulting in a failure when calling btrfs_remove_chunk() below.
2836 *
2837 * Make sure to acquire this mutex before doing a tree search (dev
2838 * or chunk trees) to find chunks. Otherwise the cleaner kthread might
2839 * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after
2840 * we release the path used to search the chunk/dev tree and before
2841 * the current task acquires this mutex and calls us.
2842 */
2843 ASSERT(mutex_is_locked(&root->fs_info->delete_unused_bgs_mutex));
2844
2845 ret = btrfs_can_relocate(extent_root, chunk_offset);
2846 if (ret)
2847 return -ENOSPC;
2848
2849 /* step one, relocate all the extents inside this chunk */
2850 btrfs_scrub_pause(root);
2851 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2852 btrfs_scrub_continue(root);
2853 if (ret)
2854 return ret;
2855
2856 trans = btrfs_start_trans_remove_block_group(root->fs_info,
2857 chunk_offset);
2858 if (IS_ERR(trans)) {
2859 ret = PTR_ERR(trans);
2860 btrfs_std_error(root->fs_info, ret, NULL);
2861 return ret;
2862 }
2863
2864 /*
2865 * step two, delete the device extents and the
2866 * chunk tree entries
2867 */
2868 ret = btrfs_remove_chunk(trans, root, chunk_offset);
2869 btrfs_end_transaction(trans, root);
2870 return ret;
2871 }
2872
2873 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2874 {
2875 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2876 struct btrfs_path *path;
2877 struct extent_buffer *leaf;
2878 struct btrfs_chunk *chunk;
2879 struct btrfs_key key;
2880 struct btrfs_key found_key;
2881 u64 chunk_type;
2882 bool retried = false;
2883 int failed = 0;
2884 int ret;
2885
2886 path = btrfs_alloc_path();
2887 if (!path)
2888 return -ENOMEM;
2889
2890 again:
2891 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2892 key.offset = (u64)-1;
2893 key.type = BTRFS_CHUNK_ITEM_KEY;
2894
2895 while (1) {
2896 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
2897 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2898 if (ret < 0) {
2899 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2900 goto error;
2901 }
2902 BUG_ON(ret == 0); /* Corruption */
2903
2904 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2905 key.type);
2906 if (ret)
2907 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2908 if (ret < 0)
2909 goto error;
2910 if (ret > 0)
2911 break;
2912
2913 leaf = path->nodes[0];
2914 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2915
2916 chunk = btrfs_item_ptr(leaf, path->slots[0],
2917 struct btrfs_chunk);
2918 chunk_type = btrfs_chunk_type(leaf, chunk);
2919 btrfs_release_path(path);
2920
2921 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2922 ret = btrfs_relocate_chunk(chunk_root,
2923 found_key.offset);
2924 if (ret == -ENOSPC)
2925 failed++;
2926 else
2927 BUG_ON(ret);
2928 }
2929 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2930
2931 if (found_key.offset == 0)
2932 break;
2933 key.offset = found_key.offset - 1;
2934 }
2935 ret = 0;
2936 if (failed && !retried) {
2937 failed = 0;
2938 retried = true;
2939 goto again;
2940 } else if (WARN_ON(failed && retried)) {
2941 ret = -ENOSPC;
2942 }
2943 error:
2944 btrfs_free_path(path);
2945 return ret;
2946 }
2947
2948 static int insert_balance_item(struct btrfs_root *root,
2949 struct btrfs_balance_control *bctl)
2950 {
2951 struct btrfs_trans_handle *trans;
2952 struct btrfs_balance_item *item;
2953 struct btrfs_disk_balance_args disk_bargs;
2954 struct btrfs_path *path;
2955 struct extent_buffer *leaf;
2956 struct btrfs_key key;
2957 int ret, err;
2958
2959 path = btrfs_alloc_path();
2960 if (!path)
2961 return -ENOMEM;
2962
2963 trans = btrfs_start_transaction(root, 0);
2964 if (IS_ERR(trans)) {
2965 btrfs_free_path(path);
2966 return PTR_ERR(trans);
2967 }
2968
2969 key.objectid = BTRFS_BALANCE_OBJECTID;
2970 key.type = BTRFS_BALANCE_ITEM_KEY;
2971 key.offset = 0;
2972
2973 ret = btrfs_insert_empty_item(trans, root, path, &key,
2974 sizeof(*item));
2975 if (ret)
2976 goto out;
2977
2978 leaf = path->nodes[0];
2979 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2980
2981 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2982
2983 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2984 btrfs_set_balance_data(leaf, item, &disk_bargs);
2985 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2986 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2987 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2988 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2989
2990 btrfs_set_balance_flags(leaf, item, bctl->flags);
2991
2992 btrfs_mark_buffer_dirty(leaf);
2993 out:
2994 btrfs_free_path(path);
2995 err = btrfs_commit_transaction(trans, root);
2996 if (err && !ret)
2997 ret = err;
2998 return ret;
2999 }
3000
3001 static int del_balance_item(struct btrfs_root *root)
3002 {
3003 struct btrfs_trans_handle *trans;
3004 struct btrfs_path *path;
3005 struct btrfs_key key;
3006 int ret, err;
3007
3008 path = btrfs_alloc_path();
3009 if (!path)
3010 return -ENOMEM;
3011
3012 trans = btrfs_start_transaction(root, 0);
3013 if (IS_ERR(trans)) {
3014 btrfs_free_path(path);
3015 return PTR_ERR(trans);
3016 }
3017
3018 key.objectid = BTRFS_BALANCE_OBJECTID;
3019 key.type = BTRFS_BALANCE_ITEM_KEY;
3020 key.offset = 0;
3021
3022 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3023 if (ret < 0)
3024 goto out;
3025 if (ret > 0) {
3026 ret = -ENOENT;
3027 goto out;
3028 }
3029
3030 ret = btrfs_del_item(trans, root, path);
3031 out:
3032 btrfs_free_path(path);
3033 err = btrfs_commit_transaction(trans, root);
3034 if (err && !ret)
3035 ret = err;
3036 return ret;
3037 }
3038
3039 /*
3040 * This is a heuristic used to reduce the number of chunks balanced on
3041 * resume after balance was interrupted.
3042 */
3043 static void update_balance_args(struct btrfs_balance_control *bctl)
3044 {
3045 /*
3046 * Turn on soft mode for chunk types that were being converted.
3047 */
3048 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
3049 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
3050 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
3051 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
3052 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
3053 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
3054
3055 /*
3056 * Turn on usage filter if is not already used. The idea is
3057 * that chunks that we have already balanced should be
3058 * reasonably full. Don't do it for chunks that are being
3059 * converted - that will keep us from relocating unconverted
3060 * (albeit full) chunks.
3061 */
3062 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3063 !(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3064 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3065 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
3066 bctl->data.usage = 90;
3067 }
3068 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3069 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3070 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3071 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
3072 bctl->sys.usage = 90;
3073 }
3074 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3075 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3076 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3077 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
3078 bctl->meta.usage = 90;
3079 }
3080 }
3081
3082 /*
3083 * Should be called with both balance and volume mutexes held to
3084 * serialize other volume operations (add_dev/rm_dev/resize) with
3085 * restriper. Same goes for unset_balance_control.
3086 */
3087 static void set_balance_control(struct btrfs_balance_control *bctl)
3088 {
3089 struct btrfs_fs_info *fs_info = bctl->fs_info;
3090
3091 BUG_ON(fs_info->balance_ctl);
3092
3093 spin_lock(&fs_info->balance_lock);
3094 fs_info->balance_ctl = bctl;
3095 spin_unlock(&fs_info->balance_lock);
3096 }
3097
3098 static void unset_balance_control(struct btrfs_fs_info *fs_info)
3099 {
3100 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3101
3102 BUG_ON(!fs_info->balance_ctl);
3103
3104 spin_lock(&fs_info->balance_lock);
3105 fs_info->balance_ctl = NULL;
3106 spin_unlock(&fs_info->balance_lock);
3107
3108 kfree(bctl);
3109 }
3110
3111 /*
3112 * Balance filters. Return 1 if chunk should be filtered out
3113 * (should not be balanced).
3114 */
3115 static int chunk_profiles_filter(u64 chunk_type,
3116 struct btrfs_balance_args *bargs)
3117 {
3118 chunk_type = chunk_to_extended(chunk_type) &
3119 BTRFS_EXTENDED_PROFILE_MASK;
3120
3121 if (bargs->profiles & chunk_type)
3122 return 0;
3123
3124 return 1;
3125 }
3126
3127 static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
3128 struct btrfs_balance_args *bargs)
3129 {
3130 struct btrfs_block_group_cache *cache;
3131 u64 chunk_used;
3132 u64 user_thresh_min;
3133 u64 user_thresh_max;
3134 int ret = 1;
3135
3136 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3137 chunk_used = btrfs_block_group_used(&cache->item);
3138
3139 if (bargs->usage_min == 0)
3140 user_thresh_min = 0;
3141 else
3142 user_thresh_min = div_factor_fine(cache->key.offset,
3143 bargs->usage_min);
3144
3145 if (bargs->usage_max == 0)
3146 user_thresh_max = 1;
3147 else if (bargs->usage_max > 100)
3148 user_thresh_max = cache->key.offset;
3149 else
3150 user_thresh_max = div_factor_fine(cache->key.offset,
3151 bargs->usage_max);
3152
3153 if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max)
3154 ret = 0;
3155
3156 btrfs_put_block_group(cache);
3157 return ret;
3158 }
3159
3160 static int chunk_usage_filter(struct btrfs_fs_info *fs_info,
3161 u64 chunk_offset, struct btrfs_balance_args *bargs)
3162 {
3163 struct btrfs_block_group_cache *cache;
3164 u64 chunk_used, user_thresh;
3165 int ret = 1;
3166
3167 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3168 chunk_used = btrfs_block_group_used(&cache->item);
3169
3170 if (bargs->usage_min == 0)
3171 user_thresh = 1;
3172 else if (bargs->usage > 100)
3173 user_thresh = cache->key.offset;
3174 else
3175 user_thresh = div_factor_fine(cache->key.offset,
3176 bargs->usage);
3177
3178 if (chunk_used < user_thresh)
3179 ret = 0;
3180
3181 btrfs_put_block_group(cache);
3182 return ret;
3183 }
3184
3185 static int chunk_devid_filter(struct extent_buffer *leaf,
3186 struct btrfs_chunk *chunk,
3187 struct btrfs_balance_args *bargs)
3188 {
3189 struct btrfs_stripe *stripe;
3190 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3191 int i;
3192
3193 for (i = 0; i < num_stripes; i++) {
3194 stripe = btrfs_stripe_nr(chunk, i);
3195 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
3196 return 0;
3197 }
3198
3199 return 1;
3200 }
3201
3202 /* [pstart, pend) */
3203 static int chunk_drange_filter(struct extent_buffer *leaf,
3204 struct btrfs_chunk *chunk,
3205 u64 chunk_offset,
3206 struct btrfs_balance_args *bargs)
3207 {
3208 struct btrfs_stripe *stripe;
3209 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3210 u64 stripe_offset;
3211 u64 stripe_length;
3212 int factor;
3213 int i;
3214
3215 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3216 return 0;
3217
3218 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
3219 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
3220 factor = num_stripes / 2;
3221 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
3222 factor = num_stripes - 1;
3223 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
3224 factor = num_stripes - 2;
3225 } else {
3226 factor = num_stripes;
3227 }
3228
3229 for (i = 0; i < num_stripes; i++) {
3230 stripe = btrfs_stripe_nr(chunk, i);
3231 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3232 continue;
3233
3234 stripe_offset = btrfs_stripe_offset(leaf, stripe);
3235 stripe_length = btrfs_chunk_length(leaf, chunk);
3236 stripe_length = div_u64(stripe_length, factor);
3237
3238 if (stripe_offset < bargs->pend &&
3239 stripe_offset + stripe_length > bargs->pstart)
3240 return 0;
3241 }
3242
3243 return 1;
3244 }
3245
3246 /* [vstart, vend) */
3247 static int chunk_vrange_filter(struct extent_buffer *leaf,
3248 struct btrfs_chunk *chunk,
3249 u64 chunk_offset,
3250 struct btrfs_balance_args *bargs)
3251 {
3252 if (chunk_offset < bargs->vend &&
3253 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
3254 /* at least part of the chunk is inside this vrange */
3255 return 0;
3256
3257 return 1;
3258 }
3259
3260 static int chunk_stripes_range_filter(struct extent_buffer *leaf,
3261 struct btrfs_chunk *chunk,
3262 struct btrfs_balance_args *bargs)
3263 {
3264 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3265
3266 if (bargs->stripes_min <= num_stripes
3267 && num_stripes <= bargs->stripes_max)
3268 return 0;
3269
3270 return 1;
3271 }
3272
3273 static int chunk_soft_convert_filter(u64 chunk_type,
3274 struct btrfs_balance_args *bargs)
3275 {
3276 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
3277 return 0;
3278
3279 chunk_type = chunk_to_extended(chunk_type) &
3280 BTRFS_EXTENDED_PROFILE_MASK;
3281
3282 if (bargs->target == chunk_type)
3283 return 1;
3284
3285 return 0;
3286 }
3287
3288 static int should_balance_chunk(struct btrfs_root *root,
3289 struct extent_buffer *leaf,
3290 struct btrfs_chunk *chunk, u64 chunk_offset)
3291 {
3292 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
3293 struct btrfs_balance_args *bargs = NULL;
3294 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
3295
3296 /* type filter */
3297 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
3298 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
3299 return 0;
3300 }
3301
3302 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3303 bargs = &bctl->data;
3304 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3305 bargs = &bctl->sys;
3306 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3307 bargs = &bctl->meta;
3308
3309 /* profiles filter */
3310 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
3311 chunk_profiles_filter(chunk_type, bargs)) {
3312 return 0;
3313 }
3314
3315 /* usage filter */
3316 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
3317 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
3318 return 0;
3319 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3320 chunk_usage_range_filter(bctl->fs_info, chunk_offset, bargs)) {
3321 return 0;
3322 }
3323
3324 /* devid filter */
3325 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
3326 chunk_devid_filter(leaf, chunk, bargs)) {
3327 return 0;
3328 }
3329
3330 /* drange filter, makes sense only with devid filter */
3331 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
3332 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
3333 return 0;
3334 }
3335
3336 /* vrange filter */
3337 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
3338 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
3339 return 0;
3340 }
3341
3342 /* stripes filter */
3343 if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) &&
3344 chunk_stripes_range_filter(leaf, chunk, bargs)) {
3345 return 0;
3346 }
3347
3348 /* soft profile changing mode */
3349 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
3350 chunk_soft_convert_filter(chunk_type, bargs)) {
3351 return 0;
3352 }
3353
3354 /*
3355 * limited by count, must be the last filter
3356 */
3357 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
3358 if (bargs->limit == 0)
3359 return 0;
3360 else
3361 bargs->limit--;
3362 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) {
3363 /*
3364 * Same logic as the 'limit' filter; the minimum cannot be
3365 * determined here because we do not have the global informatoin
3366 * about the count of all chunks that satisfy the filters.
3367 */
3368 if (bargs->limit_max == 0)
3369 return 0;
3370 else
3371 bargs->limit_max--;
3372 }
3373
3374 return 1;
3375 }
3376
3377 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
3378 {
3379 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3380 struct btrfs_root *chunk_root = fs_info->chunk_root;
3381 struct btrfs_root *dev_root = fs_info->dev_root;
3382 struct list_head *devices;
3383 struct btrfs_device *device;
3384 u64 old_size;
3385 u64 size_to_free;
3386 u64 chunk_type;
3387 struct btrfs_chunk *chunk;
3388 struct btrfs_path *path;
3389 struct btrfs_key key;
3390 struct btrfs_key found_key;
3391 struct btrfs_trans_handle *trans;
3392 struct extent_buffer *leaf;
3393 int slot;
3394 int ret;
3395 int enospc_errors = 0;
3396 bool counting = true;
3397 /* The single value limit and min/max limits use the same bytes in the */
3398 u64 limit_data = bctl->data.limit;
3399 u64 limit_meta = bctl->meta.limit;
3400 u64 limit_sys = bctl->sys.limit;
3401 u32 count_data = 0;
3402 u32 count_meta = 0;
3403 u32 count_sys = 0;
3404 int chunk_reserved = 0;
3405
3406 /* step one make some room on all the devices */
3407 devices = &fs_info->fs_devices->devices;
3408 list_for_each_entry(device, devices, dev_list) {
3409 old_size = btrfs_device_get_total_bytes(device);
3410 size_to_free = div_factor(old_size, 1);
3411 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
3412 if (!device->writeable ||
3413 btrfs_device_get_total_bytes(device) -
3414 btrfs_device_get_bytes_used(device) > size_to_free ||
3415 device->is_tgtdev_for_dev_replace)
3416 continue;
3417
3418 ret = btrfs_shrink_device(device, old_size - size_to_free);
3419 if (ret == -ENOSPC)
3420 break;
3421 BUG_ON(ret);
3422
3423 trans = btrfs_start_transaction(dev_root, 0);
3424 BUG_ON(IS_ERR(trans));
3425
3426 ret = btrfs_grow_device(trans, device, old_size);
3427 BUG_ON(ret);
3428
3429 btrfs_end_transaction(trans, dev_root);
3430 }
3431
3432 /* step two, relocate all the chunks */
3433 path = btrfs_alloc_path();
3434 if (!path) {
3435 ret = -ENOMEM;
3436 goto error;
3437 }
3438
3439 /* zero out stat counters */
3440 spin_lock(&fs_info->balance_lock);
3441 memset(&bctl->stat, 0, sizeof(bctl->stat));
3442 spin_unlock(&fs_info->balance_lock);
3443 again:
3444 if (!counting) {
3445 /*
3446 * The single value limit and min/max limits use the same bytes
3447 * in the
3448 */
3449 bctl->data.limit = limit_data;
3450 bctl->meta.limit = limit_meta;
3451 bctl->sys.limit = limit_sys;
3452 }
3453 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3454 key.offset = (u64)-1;
3455 key.type = BTRFS_CHUNK_ITEM_KEY;
3456
3457 while (1) {
3458 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
3459 atomic_read(&fs_info->balance_cancel_req)) {
3460 ret = -ECANCELED;
3461 goto error;
3462 }
3463
3464 mutex_lock(&fs_info->delete_unused_bgs_mutex);
3465 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3466 if (ret < 0) {
3467 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3468 goto error;
3469 }
3470
3471 /*
3472 * this shouldn't happen, it means the last relocate
3473 * failed
3474 */
3475 if (ret == 0)
3476 BUG(); /* FIXME break ? */
3477
3478 ret = btrfs_previous_item(chunk_root, path, 0,
3479 BTRFS_CHUNK_ITEM_KEY);
3480 if (ret) {
3481 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3482 ret = 0;
3483 break;
3484 }
3485
3486 leaf = path->nodes[0];
3487 slot = path->slots[0];
3488 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3489
3490 if (found_key.objectid != key.objectid) {
3491 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3492 break;
3493 }
3494
3495 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3496 chunk_type = btrfs_chunk_type(leaf, chunk);
3497
3498 if (!counting) {
3499 spin_lock(&fs_info->balance_lock);
3500 bctl->stat.considered++;
3501 spin_unlock(&fs_info->balance_lock);
3502 }
3503
3504 ret = should_balance_chunk(chunk_root, leaf, chunk,
3505 found_key.offset);
3506
3507 btrfs_release_path(path);
3508 if (!ret) {
3509 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3510 goto loop;
3511 }
3512
3513 if (counting) {
3514 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3515 spin_lock(&fs_info->balance_lock);
3516 bctl->stat.expected++;
3517 spin_unlock(&fs_info->balance_lock);
3518
3519 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3520 count_data++;
3521 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3522 count_sys++;
3523 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3524 count_meta++;
3525
3526 goto loop;
3527 }
3528
3529 /*
3530 * Apply limit_min filter, no need to check if the LIMITS
3531 * filter is used, limit_min is 0 by default
3532 */
3533 if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
3534 count_data < bctl->data.limit_min)
3535 || ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) &&
3536 count_meta < bctl->meta.limit_min)
3537 || ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) &&
3538 count_sys < bctl->sys.limit_min)) {
3539 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3540 goto loop;
3541 }
3542
3543 if ((chunk_type & BTRFS_BLOCK_GROUP_DATA) && !chunk_reserved) {
3544 trans = btrfs_start_transaction(chunk_root, 0);
3545 if (IS_ERR(trans)) {
3546 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3547 ret = PTR_ERR(trans);
3548 goto error;
3549 }
3550
3551 ret = btrfs_force_chunk_alloc(trans, chunk_root,
3552 BTRFS_BLOCK_GROUP_DATA);
3553 btrfs_end_transaction(trans, chunk_root);
3554 if (ret < 0) {
3555 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3556 goto error;
3557 }
3558 chunk_reserved = 1;
3559 }
3560
3561 ret = btrfs_relocate_chunk(chunk_root,
3562 found_key.offset);
3563 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3564 if (ret && ret != -ENOSPC)
3565 goto error;
3566 if (ret == -ENOSPC) {
3567 enospc_errors++;
3568 } else {
3569 spin_lock(&fs_info->balance_lock);
3570 bctl->stat.completed++;
3571 spin_unlock(&fs_info->balance_lock);
3572 }
3573 loop:
3574 if (found_key.offset == 0)
3575 break;
3576 key.offset = found_key.offset - 1;
3577 }
3578
3579 if (counting) {
3580 btrfs_release_path(path);
3581 counting = false;
3582 goto again;
3583 }
3584 error:
3585 btrfs_free_path(path);
3586 if (enospc_errors) {
3587 btrfs_info(fs_info, "%d enospc errors during balance",
3588 enospc_errors);
3589 if (!ret)
3590 ret = -ENOSPC;
3591 }
3592
3593 return ret;
3594 }
3595
3596 /**
3597 * alloc_profile_is_valid - see if a given profile is valid and reduced
3598 * @flags: profile to validate
3599 * @extended: if true @flags is treated as an extended profile
3600 */
3601 static int alloc_profile_is_valid(u64 flags, int extended)
3602 {
3603 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
3604 BTRFS_BLOCK_GROUP_PROFILE_MASK);
3605
3606 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
3607
3608 /* 1) check that all other bits are zeroed */
3609 if (flags & ~mask)
3610 return 0;
3611
3612 /* 2) see if profile is reduced */
3613 if (flags == 0)
3614 return !extended; /* "0" is valid for usual profiles */
3615
3616 /* true if exactly one bit set */
3617 return (flags & (flags - 1)) == 0;
3618 }
3619
3620 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
3621 {
3622 /* cancel requested || normal exit path */
3623 return atomic_read(&fs_info->balance_cancel_req) ||
3624 (atomic_read(&fs_info->balance_pause_req) == 0 &&
3625 atomic_read(&fs_info->balance_cancel_req) == 0);
3626 }
3627
3628 static void __cancel_balance(struct btrfs_fs_info *fs_info)
3629 {
3630 int ret;
3631
3632 unset_balance_control(fs_info);
3633 ret = del_balance_item(fs_info->tree_root);
3634 if (ret)
3635 btrfs_std_error(fs_info, ret, NULL);
3636
3637 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3638 }
3639
3640 /* Non-zero return value signifies invalidity */
3641 static inline int validate_convert_profile(struct btrfs_balance_args *bctl_arg,
3642 u64 allowed)
3643 {
3644 return ((bctl_arg->flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3645 (!alloc_profile_is_valid(bctl_arg->target, 1) ||
3646 (bctl_arg->target & ~allowed)));
3647 }
3648
3649 /*
3650 * Should be called with both balance and volume mutexes held
3651 */
3652 int btrfs_balance(struct btrfs_balance_control *bctl,
3653 struct btrfs_ioctl_balance_args *bargs)
3654 {
3655 struct btrfs_fs_info *fs_info = bctl->fs_info;
3656 u64 allowed;
3657 int mixed = 0;
3658 int ret;
3659 u64 num_devices;
3660 unsigned seq;
3661
3662 if (btrfs_fs_closing(fs_info) ||
3663 atomic_read(&fs_info->balance_pause_req) ||
3664 atomic_read(&fs_info->balance_cancel_req)) {
3665 ret = -EINVAL;
3666 goto out;
3667 }
3668
3669 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3670 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3671 mixed = 1;
3672
3673 /*
3674 * In case of mixed groups both data and meta should be picked,
3675 * and identical options should be given for both of them.
3676 */
3677 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3678 if (mixed && (bctl->flags & allowed)) {
3679 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3680 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3681 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3682 btrfs_err(fs_info, "with mixed groups data and "
3683 "metadata balance options must be the same");
3684 ret = -EINVAL;
3685 goto out;
3686 }
3687 }
3688
3689 num_devices = fs_info->fs_devices->num_devices;
3690 btrfs_dev_replace_lock(&fs_info->dev_replace);
3691 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3692 BUG_ON(num_devices < 1);
3693 num_devices--;
3694 }
3695 btrfs_dev_replace_unlock(&fs_info->dev_replace);
3696 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3697 if (num_devices == 1)
3698 allowed |= BTRFS_BLOCK_GROUP_DUP;
3699 else if (num_devices > 1)
3700 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3701 if (num_devices > 2)
3702 allowed |= BTRFS_BLOCK_GROUP_RAID5;
3703 if (num_devices > 3)
3704 allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
3705 BTRFS_BLOCK_GROUP_RAID6);
3706 if (validate_convert_profile(&bctl->data, allowed)) {
3707 btrfs_err(fs_info, "unable to start balance with target "
3708 "data profile %llu",
3709 bctl->data.target);
3710 ret = -EINVAL;
3711 goto out;
3712 }
3713 if (validate_convert_profile(&bctl->meta, allowed)) {
3714 btrfs_err(fs_info,
3715 "unable to start balance with target metadata profile %llu",
3716 bctl->meta.target);
3717 ret = -EINVAL;
3718 goto out;
3719 }
3720 if (validate_convert_profile(&bctl->sys, allowed)) {
3721 btrfs_err(fs_info,
3722 "unable to start balance with target system profile %llu",
3723 bctl->sys.target);
3724 ret = -EINVAL;
3725 goto out;
3726 }
3727
3728 /* allow dup'ed data chunks only in mixed mode */
3729 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3730 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
3731 btrfs_err(fs_info, "dup for data is not allowed");
3732 ret = -EINVAL;
3733 goto out;
3734 }
3735
3736 /* allow to reduce meta or sys integrity only if force set */
3737 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3738 BTRFS_BLOCK_GROUP_RAID10 |
3739 BTRFS_BLOCK_GROUP_RAID5 |
3740 BTRFS_BLOCK_GROUP_RAID6;
3741 do {
3742 seq = read_seqbegin(&fs_info->profiles_lock);
3743
3744 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3745 (fs_info->avail_system_alloc_bits & allowed) &&
3746 !(bctl->sys.target & allowed)) ||
3747 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3748 (fs_info->avail_metadata_alloc_bits & allowed) &&
3749 !(bctl->meta.target & allowed))) {
3750 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3751 btrfs_info(fs_info, "force reducing metadata integrity");
3752 } else {
3753 btrfs_err(fs_info, "balance will reduce metadata "
3754 "integrity, use force if you want this");
3755 ret = -EINVAL;
3756 goto out;
3757 }
3758 }
3759 } while (read_seqretry(&fs_info->profiles_lock, seq));
3760
3761 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3762 fs_info->num_tolerated_disk_barrier_failures = min(
3763 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info),
3764 btrfs_get_num_tolerated_disk_barrier_failures(
3765 bctl->sys.target));
3766 }
3767
3768 ret = insert_balance_item(fs_info->tree_root, bctl);
3769 if (ret && ret != -EEXIST)
3770 goto out;
3771
3772 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3773 BUG_ON(ret == -EEXIST);
3774 set_balance_control(bctl);
3775 } else {
3776 BUG_ON(ret != -EEXIST);
3777 spin_lock(&fs_info->balance_lock);
3778 update_balance_args(bctl);
3779 spin_unlock(&fs_info->balance_lock);
3780 }
3781
3782 atomic_inc(&fs_info->balance_running);
3783 mutex_unlock(&fs_info->balance_mutex);
3784
3785 ret = __btrfs_balance(fs_info);
3786
3787 mutex_lock(&fs_info->balance_mutex);
3788 atomic_dec(&fs_info->balance_running);
3789
3790 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3791 fs_info->num_tolerated_disk_barrier_failures =
3792 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3793 }
3794
3795 if (bargs) {
3796 memset(bargs, 0, sizeof(*bargs));
3797 update_ioctl_balance_args(fs_info, 0, bargs);
3798 }
3799
3800 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3801 balance_need_close(fs_info)) {
3802 __cancel_balance(fs_info);
3803 }
3804
3805 wake_up(&fs_info->balance_wait_q);
3806
3807 return ret;
3808 out:
3809 if (bctl->flags & BTRFS_BALANCE_RESUME)
3810 __cancel_balance(fs_info);
3811 else {
3812 kfree(bctl);
3813 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3814 }
3815 return ret;
3816 }
3817
3818 static int balance_kthread(void *data)
3819 {
3820 struct btrfs_fs_info *fs_info = data;
3821 int ret = 0;
3822
3823 mutex_lock(&fs_info->volume_mutex);
3824 mutex_lock(&fs_info->balance_mutex);
3825
3826 if (fs_info->balance_ctl) {
3827 btrfs_info(fs_info, "continuing balance");
3828 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3829 }
3830
3831 mutex_unlock(&fs_info->balance_mutex);
3832 mutex_unlock(&fs_info->volume_mutex);
3833
3834 return ret;
3835 }
3836
3837 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3838 {
3839 struct task_struct *tsk;
3840
3841 spin_lock(&fs_info->balance_lock);
3842 if (!fs_info->balance_ctl) {
3843 spin_unlock(&fs_info->balance_lock);
3844 return 0;
3845 }
3846 spin_unlock(&fs_info->balance_lock);
3847
3848 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3849 btrfs_info(fs_info, "force skipping balance");
3850 return 0;
3851 }
3852
3853 /*
3854 * A ro->rw remount sequence should continue with the paused balance
3855 * regardless of who pauses it, system or the user as of now, so set
3856 * the resume flag.
3857 */
3858 spin_lock(&fs_info->balance_lock);
3859 fs_info->balance_ctl->flags |= BTRFS_BALANCE_RESUME;
3860 spin_unlock(&fs_info->balance_lock);
3861
3862 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3863 return PTR_ERR_OR_ZERO(tsk);
3864 }
3865
3866 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3867 {
3868 struct btrfs_balance_control *bctl;
3869 struct btrfs_balance_item *item;
3870 struct btrfs_disk_balance_args disk_bargs;
3871 struct btrfs_path *path;
3872 struct extent_buffer *leaf;
3873 struct btrfs_key key;
3874 int ret;
3875
3876 path = btrfs_alloc_path();
3877 if (!path)
3878 return -ENOMEM;
3879
3880 key.objectid = BTRFS_BALANCE_OBJECTID;
3881 key.type = BTRFS_BALANCE_ITEM_KEY;
3882 key.offset = 0;
3883
3884 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3885 if (ret < 0)
3886 goto out;
3887 if (ret > 0) { /* ret = -ENOENT; */
3888 ret = 0;
3889 goto out;
3890 }
3891
3892 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3893 if (!bctl) {
3894 ret = -ENOMEM;
3895 goto out;
3896 }
3897
3898 leaf = path->nodes[0];
3899 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3900
3901 bctl->fs_info = fs_info;
3902 bctl->flags = btrfs_balance_flags(leaf, item);
3903 bctl->flags |= BTRFS_BALANCE_RESUME;
3904
3905 btrfs_balance_data(leaf, item, &disk_bargs);
3906 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3907 btrfs_balance_meta(leaf, item, &disk_bargs);
3908 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3909 btrfs_balance_sys(leaf, item, &disk_bargs);
3910 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3911
3912 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3913
3914 mutex_lock(&fs_info->volume_mutex);
3915 mutex_lock(&fs_info->balance_mutex);
3916
3917 set_balance_control(bctl);
3918
3919 mutex_unlock(&fs_info->balance_mutex);
3920 mutex_unlock(&fs_info->volume_mutex);
3921 out:
3922 btrfs_free_path(path);
3923 return ret;
3924 }
3925
3926 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3927 {
3928 int ret = 0;
3929
3930 mutex_lock(&fs_info->balance_mutex);
3931 if (!fs_info->balance_ctl) {
3932 mutex_unlock(&fs_info->balance_mutex);
3933 return -ENOTCONN;
3934 }
3935
3936 if (atomic_read(&fs_info->balance_running)) {
3937 atomic_inc(&fs_info->balance_pause_req);
3938 mutex_unlock(&fs_info->balance_mutex);
3939
3940 wait_event(fs_info->balance_wait_q,
3941 atomic_read(&fs_info->balance_running) == 0);
3942
3943 mutex_lock(&fs_info->balance_mutex);
3944 /* we are good with balance_ctl ripped off from under us */
3945 BUG_ON(atomic_read(&fs_info->balance_running));
3946 atomic_dec(&fs_info->balance_pause_req);
3947 } else {
3948 ret = -ENOTCONN;
3949 }
3950
3951 mutex_unlock(&fs_info->balance_mutex);
3952 return ret;
3953 }
3954
3955 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3956 {
3957 if (fs_info->sb->s_flags & MS_RDONLY)
3958 return -EROFS;
3959
3960 mutex_lock(&fs_info->balance_mutex);
3961 if (!fs_info->balance_ctl) {
3962 mutex_unlock(&fs_info->balance_mutex);
3963 return -ENOTCONN;
3964 }
3965
3966 atomic_inc(&fs_info->balance_cancel_req);
3967 /*
3968 * if we are running just wait and return, balance item is
3969 * deleted in btrfs_balance in this case
3970 */
3971 if (atomic_read(&fs_info->balance_running)) {
3972 mutex_unlock(&fs_info->balance_mutex);
3973 wait_event(fs_info->balance_wait_q,
3974 atomic_read(&fs_info->balance_running) == 0);
3975 mutex_lock(&fs_info->balance_mutex);
3976 } else {
3977 /* __cancel_balance needs volume_mutex */
3978 mutex_unlock(&fs_info->balance_mutex);
3979 mutex_lock(&fs_info->volume_mutex);
3980 mutex_lock(&fs_info->balance_mutex);
3981
3982 if (fs_info->balance_ctl)
3983 __cancel_balance(fs_info);
3984
3985 mutex_unlock(&fs_info->volume_mutex);
3986 }
3987
3988 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
3989 atomic_dec(&fs_info->balance_cancel_req);
3990 mutex_unlock(&fs_info->balance_mutex);
3991 return 0;
3992 }
3993
3994 static int btrfs_uuid_scan_kthread(void *data)
3995 {
3996 struct btrfs_fs_info *fs_info = data;
3997 struct btrfs_root *root = fs_info->tree_root;
3998 struct btrfs_key key;
3999 struct btrfs_key max_key;
4000 struct btrfs_path *path = NULL;
4001 int ret = 0;
4002 struct extent_buffer *eb;
4003 int slot;
4004 struct btrfs_root_item root_item;
4005 u32 item_size;
4006 struct btrfs_trans_handle *trans = NULL;
4007
4008 path = btrfs_alloc_path();
4009 if (!path) {
4010 ret = -ENOMEM;
4011 goto out;
4012 }
4013
4014 key.objectid = 0;
4015 key.type = BTRFS_ROOT_ITEM_KEY;
4016 key.offset = 0;
4017
4018 max_key.objectid = (u64)-1;
4019 max_key.type = BTRFS_ROOT_ITEM_KEY;
4020 max_key.offset = (u64)-1;
4021
4022 while (1) {
4023 ret = btrfs_search_forward(root, &key, path, 0);
4024 if (ret) {
4025 if (ret > 0)
4026 ret = 0;
4027 break;
4028 }
4029
4030 if (key.type != BTRFS_ROOT_ITEM_KEY ||
4031 (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
4032 key.objectid != BTRFS_FS_TREE_OBJECTID) ||
4033 key.objectid > BTRFS_LAST_FREE_OBJECTID)
4034 goto skip;
4035
4036 eb = path->nodes[0];
4037 slot = path->slots[0];
4038 item_size = btrfs_item_size_nr(eb, slot);
4039 if (item_size < sizeof(root_item))
4040 goto skip;
4041
4042 read_extent_buffer(eb, &root_item,
4043 btrfs_item_ptr_offset(eb, slot),
4044 (int)sizeof(root_item));
4045 if (btrfs_root_refs(&root_item) == 0)
4046 goto skip;
4047
4048 if (!btrfs_is_empty_uuid(root_item.uuid) ||
4049 !btrfs_is_empty_uuid(root_item.received_uuid)) {
4050 if (trans)
4051 goto update_tree;
4052
4053 btrfs_release_path(path);
4054 /*
4055 * 1 - subvol uuid item
4056 * 1 - received_subvol uuid item
4057 */
4058 trans = btrfs_start_transaction(fs_info->uuid_root, 2);
4059 if (IS_ERR(trans)) {
4060 ret = PTR_ERR(trans);
4061 break;
4062 }
4063 continue;
4064 } else {
4065 goto skip;
4066 }
4067 update_tree:
4068 if (!btrfs_is_empty_uuid(root_item.uuid)) {
4069 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
4070 root_item.uuid,
4071 BTRFS_UUID_KEY_SUBVOL,
4072 key.objectid);
4073 if (ret < 0) {
4074 btrfs_warn(fs_info, "uuid_tree_add failed %d",
4075 ret);
4076 break;
4077 }
4078 }
4079
4080 if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
4081 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
4082 root_item.received_uuid,
4083 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4084 key.objectid);
4085 if (ret < 0) {
4086 btrfs_warn(fs_info, "uuid_tree_add failed %d",
4087 ret);
4088 break;
4089 }
4090 }
4091
4092 skip:
4093 if (trans) {
4094 ret = btrfs_end_transaction(trans, fs_info->uuid_root);
4095 trans = NULL;
4096 if (ret)
4097 break;
4098 }
4099
4100 btrfs_release_path(path);
4101 if (key.offset < (u64)-1) {
4102 key.offset++;
4103 } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
4104 key.offset = 0;
4105 key.type = BTRFS_ROOT_ITEM_KEY;
4106 } else if (key.objectid < (u64)-1) {
4107 key.offset = 0;
4108 key.type = BTRFS_ROOT_ITEM_KEY;
4109 key.objectid++;
4110 } else {
4111 break;
4112 }
4113 cond_resched();
4114 }
4115
4116 out:
4117 btrfs_free_path(path);
4118 if (trans && !IS_ERR(trans))
4119 btrfs_end_transaction(trans, fs_info->uuid_root);
4120 if (ret)
4121 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
4122 else
4123 fs_info->update_uuid_tree_gen = 1;
4124 up(&fs_info->uuid_tree_rescan_sem);
4125 return 0;
4126 }
4127
4128 /*
4129 * Callback for btrfs_uuid_tree_iterate().
4130 * returns:
4131 * 0 check succeeded, the entry is not outdated.
4132 * < 0 if an error occured.
4133 * > 0 if the check failed, which means the caller shall remove the entry.
4134 */
4135 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
4136 u8 *uuid, u8 type, u64 subid)
4137 {
4138 struct btrfs_key key;
4139 int ret = 0;
4140 struct btrfs_root *subvol_root;
4141
4142 if (type != BTRFS_UUID_KEY_SUBVOL &&
4143 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
4144 goto out;
4145
4146 key.objectid = subid;
4147 key.type = BTRFS_ROOT_ITEM_KEY;
4148 key.offset = (u64)-1;
4149 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
4150 if (IS_ERR(subvol_root)) {
4151 ret = PTR_ERR(subvol_root);
4152 if (ret == -ENOENT)
4153 ret = 1;
4154 goto out;
4155 }
4156
4157 switch (type) {
4158 case BTRFS_UUID_KEY_SUBVOL:
4159 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
4160 ret = 1;
4161 break;
4162 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
4163 if (memcmp(uuid, subvol_root->root_item.received_uuid,
4164 BTRFS_UUID_SIZE))
4165 ret = 1;
4166 break;
4167 }
4168
4169 out:
4170 return ret;
4171 }
4172
4173 static int btrfs_uuid_rescan_kthread(void *data)
4174 {
4175 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
4176 int ret;
4177
4178 /*
4179 * 1st step is to iterate through the existing UUID tree and
4180 * to delete all entries that contain outdated data.
4181 * 2nd step is to add all missing entries to the UUID tree.
4182 */
4183 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
4184 if (ret < 0) {
4185 btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
4186 up(&fs_info->uuid_tree_rescan_sem);
4187 return ret;
4188 }
4189 return btrfs_uuid_scan_kthread(data);
4190 }
4191
4192 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
4193 {
4194 struct btrfs_trans_handle *trans;
4195 struct btrfs_root *tree_root = fs_info->tree_root;
4196 struct btrfs_root *uuid_root;
4197 struct task_struct *task;
4198 int ret;
4199
4200 /*
4201 * 1 - root node
4202 * 1 - root item
4203 */
4204 trans = btrfs_start_transaction(tree_root, 2);
4205 if (IS_ERR(trans))
4206 return PTR_ERR(trans);
4207
4208 uuid_root = btrfs_create_tree(trans, fs_info,
4209 BTRFS_UUID_TREE_OBJECTID);
4210 if (IS_ERR(uuid_root)) {
4211 ret = PTR_ERR(uuid_root);
4212 btrfs_abort_transaction(trans, tree_root, ret);
4213 return ret;
4214 }
4215
4216 fs_info->uuid_root = uuid_root;
4217
4218 ret = btrfs_commit_transaction(trans, tree_root);
4219 if (ret)
4220 return ret;
4221
4222 down(&fs_info->uuid_tree_rescan_sem);
4223 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
4224 if (IS_ERR(task)) {
4225 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
4226 btrfs_warn(fs_info, "failed to start uuid_scan task");
4227 up(&fs_info->uuid_tree_rescan_sem);
4228 return PTR_ERR(task);
4229 }
4230
4231 return 0;
4232 }
4233
4234 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
4235 {
4236 struct task_struct *task;
4237
4238 down(&fs_info->uuid_tree_rescan_sem);
4239 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
4240 if (IS_ERR(task)) {
4241 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
4242 btrfs_warn(fs_info, "failed to start uuid_rescan task");
4243 up(&fs_info->uuid_tree_rescan_sem);
4244 return PTR_ERR(task);
4245 }
4246
4247 return 0;
4248 }
4249
4250 /*
4251 * shrinking a device means finding all of the device extents past
4252 * the new size, and then following the back refs to the chunks.
4253 * The chunk relocation code actually frees the device extent
4254 */
4255 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
4256 {
4257 struct btrfs_trans_handle *trans;
4258 struct btrfs_root *root = device->dev_root;
4259 struct btrfs_dev_extent *dev_extent = NULL;
4260 struct btrfs_path *path;
4261 u64 length;
4262 u64 chunk_offset;
4263 int ret;
4264 int slot;
4265 int failed = 0;
4266 bool retried = false;
4267 bool checked_pending_chunks = false;
4268 struct extent_buffer *l;
4269 struct btrfs_key key;
4270 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4271 u64 old_total = btrfs_super_total_bytes(super_copy);
4272 u64 old_size = btrfs_device_get_total_bytes(device);
4273 u64 diff = old_size - new_size;
4274
4275 if (device->is_tgtdev_for_dev_replace)
4276 return -EINVAL;
4277
4278 path = btrfs_alloc_path();
4279 if (!path)
4280 return -ENOMEM;
4281
4282 path->reada = 2;
4283
4284 lock_chunks(root);
4285
4286 btrfs_device_set_total_bytes(device, new_size);
4287 if (device->writeable) {
4288 device->fs_devices->total_rw_bytes -= diff;
4289 spin_lock(&root->fs_info->free_chunk_lock);
4290 root->fs_info->free_chunk_space -= diff;
4291 spin_unlock(&root->fs_info->free_chunk_lock);
4292 }
4293 unlock_chunks(root);
4294
4295 again:
4296 key.objectid = device->devid;
4297 key.offset = (u64)-1;
4298 key.type = BTRFS_DEV_EXTENT_KEY;
4299
4300 do {
4301 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
4302 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4303 if (ret < 0) {
4304 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4305 goto done;
4306 }
4307
4308 ret = btrfs_previous_item(root, path, 0, key.type);
4309 if (ret)
4310 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4311 if (ret < 0)
4312 goto done;
4313 if (ret) {
4314 ret = 0;
4315 btrfs_release_path(path);
4316 break;
4317 }
4318
4319 l = path->nodes[0];
4320 slot = path->slots[0];
4321 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
4322
4323 if (key.objectid != device->devid) {
4324 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4325 btrfs_release_path(path);
4326 break;
4327 }
4328
4329 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
4330 length = btrfs_dev_extent_length(l, dev_extent);
4331
4332 if (key.offset + length <= new_size) {
4333 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4334 btrfs_release_path(path);
4335 break;
4336 }
4337
4338 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
4339 btrfs_release_path(path);
4340
4341 ret = btrfs_relocate_chunk(root, chunk_offset);
4342 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4343 if (ret && ret != -ENOSPC)
4344 goto done;
4345 if (ret == -ENOSPC)
4346 failed++;
4347 } while (key.offset-- > 0);
4348
4349 if (failed && !retried) {
4350 failed = 0;
4351 retried = true;
4352 goto again;
4353 } else if (failed && retried) {
4354 ret = -ENOSPC;
4355 goto done;
4356 }
4357
4358 /* Shrinking succeeded, else we would be at "done". */
4359 trans = btrfs_start_transaction(root, 0);
4360 if (IS_ERR(trans)) {
4361 ret = PTR_ERR(trans);
4362 goto done;
4363 }
4364
4365 lock_chunks(root);
4366
4367 /*
4368 * We checked in the above loop all device extents that were already in
4369 * the device tree. However before we have updated the device's
4370 * total_bytes to the new size, we might have had chunk allocations that
4371 * have not complete yet (new block groups attached to transaction
4372 * handles), and therefore their device extents were not yet in the
4373 * device tree and we missed them in the loop above. So if we have any
4374 * pending chunk using a device extent that overlaps the device range
4375 * that we can not use anymore, commit the current transaction and
4376 * repeat the search on the device tree - this way we guarantee we will
4377 * not have chunks using device extents that end beyond 'new_size'.
4378 */
4379 if (!checked_pending_chunks) {
4380 u64 start = new_size;
4381 u64 len = old_size - new_size;
4382
4383 if (contains_pending_extent(trans->transaction, device,
4384 &start, len)) {
4385 unlock_chunks(root);
4386 checked_pending_chunks = true;
4387 failed = 0;
4388 retried = false;
4389 ret = btrfs_commit_transaction(trans, root);
4390 if (ret)
4391 goto done;
4392 goto again;
4393 }
4394 }
4395
4396 btrfs_device_set_disk_total_bytes(device, new_size);
4397 if (list_empty(&device->resized_list))
4398 list_add_tail(&device->resized_list,
4399 &root->fs_info->fs_devices->resized_devices);
4400
4401 WARN_ON(diff > old_total);
4402 btrfs_set_super_total_bytes(super_copy, old_total - diff);
4403 unlock_chunks(root);
4404
4405 /* Now btrfs_update_device() will change the on-disk size. */
4406 ret = btrfs_update_device(trans, device);
4407 btrfs_end_transaction(trans, root);
4408 done:
4409 btrfs_free_path(path);
4410 if (ret) {
4411 lock_chunks(root);
4412 btrfs_device_set_total_bytes(device, old_size);
4413 if (device->writeable)
4414 device->fs_devices->total_rw_bytes += diff;
4415 spin_lock(&root->fs_info->free_chunk_lock);
4416 root->fs_info->free_chunk_space += diff;
4417 spin_unlock(&root->fs_info->free_chunk_lock);
4418 unlock_chunks(root);
4419 }
4420 return ret;
4421 }
4422
4423 static int btrfs_add_system_chunk(struct btrfs_root *root,
4424 struct btrfs_key *key,
4425 struct btrfs_chunk *chunk, int item_size)
4426 {
4427 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4428 struct btrfs_disk_key disk_key;
4429 u32 array_size;
4430 u8 *ptr;
4431
4432 lock_chunks(root);
4433 array_size = btrfs_super_sys_array_size(super_copy);
4434 if (array_size + item_size + sizeof(disk_key)
4435 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
4436 unlock_chunks(root);
4437 return -EFBIG;
4438 }
4439
4440 ptr = super_copy->sys_chunk_array + array_size;
4441 btrfs_cpu_key_to_disk(&disk_key, key);
4442 memcpy(ptr, &disk_key, sizeof(disk_key));
4443 ptr += sizeof(disk_key);
4444 memcpy(ptr, chunk, item_size);
4445 item_size += sizeof(disk_key);
4446 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
4447 unlock_chunks(root);
4448
4449 return 0;
4450 }
4451
4452 /*
4453 * sort the devices in descending order by max_avail, total_avail
4454 */
4455 static int btrfs_cmp_device_info(const void *a, const void *b)
4456 {
4457 const struct btrfs_device_info *di_a = a;
4458 const struct btrfs_device_info *di_b = b;
4459
4460 if (di_a->max_avail > di_b->max_avail)
4461 return -1;
4462 if (di_a->max_avail < di_b->max_avail)
4463 return 1;
4464 if (di_a->total_avail > di_b->total_avail)
4465 return -1;
4466 if (di_a->total_avail < di_b->total_avail)
4467 return 1;
4468 return 0;
4469 }
4470
4471 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
4472 {
4473 /* TODO allow them to set a preferred stripe size */
4474 return 64 * 1024;
4475 }
4476
4477 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
4478 {
4479 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
4480 return;
4481
4482 btrfs_set_fs_incompat(info, RAID56);
4483 }
4484
4485 #define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \
4486 - sizeof(struct btrfs_item) \
4487 - sizeof(struct btrfs_chunk)) \
4488 / sizeof(struct btrfs_stripe) + 1)
4489
4490 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
4491 - 2 * sizeof(struct btrfs_disk_key) \
4492 - 2 * sizeof(struct btrfs_chunk)) \
4493 / sizeof(struct btrfs_stripe) + 1)
4494
4495 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4496 struct btrfs_root *extent_root, u64 start,
4497 u64 type)
4498 {
4499 struct btrfs_fs_info *info = extent_root->fs_info;
4500 struct btrfs_fs_devices *fs_devices = info->fs_devices;
4501 struct list_head *cur;
4502 struct map_lookup *map = NULL;
4503 struct extent_map_tree *em_tree;
4504 struct extent_map *em;
4505 struct btrfs_device_info *devices_info = NULL;
4506 u64 total_avail;
4507 int num_stripes; /* total number of stripes to allocate */
4508 int data_stripes; /* number of stripes that count for
4509 block group size */
4510 int sub_stripes; /* sub_stripes info for map */
4511 int dev_stripes; /* stripes per dev */
4512 int devs_max; /* max devs to use */
4513 int devs_min; /* min devs needed */
4514 int devs_increment; /* ndevs has to be a multiple of this */
4515 int ncopies; /* how many copies to data has */
4516 int ret;
4517 u64 max_stripe_size;
4518 u64 max_chunk_size;
4519 u64 stripe_size;
4520 u64 num_bytes;
4521 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
4522 int ndevs;
4523 int i;
4524 int j;
4525 int index;
4526
4527 BUG_ON(!alloc_profile_is_valid(type, 0));
4528
4529 if (list_empty(&fs_devices->alloc_list))
4530 return -ENOSPC;
4531
4532 index = __get_raid_index(type);
4533
4534 sub_stripes = btrfs_raid_array[index].sub_stripes;
4535 dev_stripes = btrfs_raid_array[index].dev_stripes;
4536 devs_max = btrfs_raid_array[index].devs_max;
4537 devs_min = btrfs_raid_array[index].devs_min;
4538 devs_increment = btrfs_raid_array[index].devs_increment;
4539 ncopies = btrfs_raid_array[index].ncopies;
4540
4541 if (type & BTRFS_BLOCK_GROUP_DATA) {
4542 max_stripe_size = 1024 * 1024 * 1024;
4543 max_chunk_size = 10 * max_stripe_size;
4544 if (!devs_max)
4545 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4546 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
4547 /* for larger filesystems, use larger metadata chunks */
4548 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
4549 max_stripe_size = 1024 * 1024 * 1024;
4550 else
4551 max_stripe_size = 256 * 1024 * 1024;
4552 max_chunk_size = max_stripe_size;
4553 if (!devs_max)
4554 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4555 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
4556 max_stripe_size = 32 * 1024 * 1024;
4557 max_chunk_size = 2 * max_stripe_size;
4558 if (!devs_max)
4559 devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
4560 } else {
4561 btrfs_err(info, "invalid chunk type 0x%llx requested",
4562 type);
4563 BUG_ON(1);
4564 }
4565
4566 /* we don't want a chunk larger than 10% of writeable space */
4567 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
4568 max_chunk_size);
4569
4570 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
4571 GFP_NOFS);
4572 if (!devices_info)
4573 return -ENOMEM;
4574
4575 cur = fs_devices->alloc_list.next;
4576
4577 /*
4578 * in the first pass through the devices list, we gather information
4579 * about the available holes on each device.
4580 */
4581 ndevs = 0;
4582 while (cur != &fs_devices->alloc_list) {
4583 struct btrfs_device *device;
4584 u64 max_avail;
4585 u64 dev_offset;
4586
4587 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
4588
4589 cur = cur->next;
4590
4591 if (!device->writeable) {
4592 WARN(1, KERN_ERR
4593 "BTRFS: read-only device in alloc_list\n");
4594 continue;
4595 }
4596
4597 if (!device->in_fs_metadata ||
4598 device->is_tgtdev_for_dev_replace)
4599 continue;
4600
4601 if (device->total_bytes > device->bytes_used)
4602 total_avail = device->total_bytes - device->bytes_used;
4603 else
4604 total_avail = 0;
4605
4606 /* If there is no space on this device, skip it. */
4607 if (total_avail == 0)
4608 continue;
4609
4610 ret = find_free_dev_extent(trans, device,
4611 max_stripe_size * dev_stripes,
4612 &dev_offset, &max_avail);
4613 if (ret && ret != -ENOSPC)
4614 goto error;
4615
4616 if (ret == 0)
4617 max_avail = max_stripe_size * dev_stripes;
4618
4619 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
4620 continue;
4621
4622 if (ndevs == fs_devices->rw_devices) {
4623 WARN(1, "%s: found more than %llu devices\n",
4624 __func__, fs_devices->rw_devices);
4625 break;
4626 }
4627 devices_info[ndevs].dev_offset = dev_offset;
4628 devices_info[ndevs].max_avail = max_avail;
4629 devices_info[ndevs].total_avail = total_avail;
4630 devices_info[ndevs].dev = device;
4631 ++ndevs;
4632 }
4633
4634 /*
4635 * now sort the devices by hole size / available space
4636 */
4637 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
4638 btrfs_cmp_device_info, NULL);
4639
4640 /* round down to number of usable stripes */
4641 ndevs -= ndevs % devs_increment;
4642
4643 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
4644 ret = -ENOSPC;
4645 goto error;
4646 }
4647
4648 if (devs_max && ndevs > devs_max)
4649 ndevs = devs_max;
4650 /*
4651 * The primary goal is to maximize the number of stripes, so use as
4652 * many devices as possible, even if the stripes are not maximum sized.
4653 *
4654 * The DUP profile stores more than one stripe per device, the
4655 * max_avail is the total size so we have to adjust.
4656 */
4657 stripe_size = div_u64(devices_info[ndevs - 1].max_avail, dev_stripes);
4658 num_stripes = ndevs * dev_stripes;
4659
4660 /*
4661 * this will have to be fixed for RAID1 and RAID10 over
4662 * more drives
4663 */
4664 data_stripes = num_stripes / ncopies;
4665
4666 if (type & BTRFS_BLOCK_GROUP_RAID5) {
4667 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
4668 btrfs_super_stripesize(info->super_copy));
4669 data_stripes = num_stripes - 1;
4670 }
4671 if (type & BTRFS_BLOCK_GROUP_RAID6) {
4672 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
4673 btrfs_super_stripesize(info->super_copy));
4674 data_stripes = num_stripes - 2;
4675 }
4676
4677 /*
4678 * Use the number of data stripes to figure out how big this chunk
4679 * is really going to be in terms of logical address space,
4680 * and compare that answer with the max chunk size
4681 */
4682 if (stripe_size * data_stripes > max_chunk_size) {
4683 u64 mask = (1ULL << 24) - 1;
4684
4685 stripe_size = div_u64(max_chunk_size, data_stripes);
4686
4687 /* bump the answer up to a 16MB boundary */
4688 stripe_size = (stripe_size + mask) & ~mask;
4689
4690 /* but don't go higher than the limits we found
4691 * while searching for free extents
4692 */
4693 if (stripe_size > devices_info[ndevs-1].max_avail)
4694 stripe_size = devices_info[ndevs-1].max_avail;
4695 }
4696
4697 /* align to BTRFS_STRIPE_LEN */
4698 stripe_size = div_u64(stripe_size, raid_stripe_len);
4699 stripe_size *= raid_stripe_len;
4700
4701 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4702 if (!map) {
4703 ret = -ENOMEM;
4704 goto error;
4705 }
4706 map->num_stripes = num_stripes;
4707
4708 for (i = 0; i < ndevs; ++i) {
4709 for (j = 0; j < dev_stripes; ++j) {
4710 int s = i * dev_stripes + j;
4711 map->stripes[s].dev = devices_info[i].dev;
4712 map->stripes[s].physical = devices_info[i].dev_offset +
4713 j * stripe_size;
4714 }
4715 }
4716 map->sector_size = extent_root->sectorsize;
4717 map->stripe_len = raid_stripe_len;
4718 map->io_align = raid_stripe_len;
4719 map->io_width = raid_stripe_len;
4720 map->type = type;
4721 map->sub_stripes = sub_stripes;
4722
4723 num_bytes = stripe_size * data_stripes;
4724
4725 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
4726
4727 em = alloc_extent_map();
4728 if (!em) {
4729 kfree(map);
4730 ret = -ENOMEM;
4731 goto error;
4732 }
4733 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
4734 em->bdev = (struct block_device *)map;
4735 em->start = start;
4736 em->len = num_bytes;
4737 em->block_start = 0;
4738 em->block_len = em->len;
4739 em->orig_block_len = stripe_size;
4740
4741 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4742 write_lock(&em_tree->lock);
4743 ret = add_extent_mapping(em_tree, em, 0);
4744 if (!ret) {
4745 list_add_tail(&em->list, &trans->transaction->pending_chunks);
4746 atomic_inc(&em->refs);
4747 }
4748 write_unlock(&em_tree->lock);
4749 if (ret) {
4750 free_extent_map(em);
4751 goto error;
4752 }
4753
4754 ret = btrfs_make_block_group(trans, extent_root, 0, type,
4755 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4756 start, num_bytes);
4757 if (ret)
4758 goto error_del_extent;
4759
4760 for (i = 0; i < map->num_stripes; i++) {
4761 num_bytes = map->stripes[i].dev->bytes_used + stripe_size;
4762 btrfs_device_set_bytes_used(map->stripes[i].dev, num_bytes);
4763 }
4764
4765 spin_lock(&extent_root->fs_info->free_chunk_lock);
4766 extent_root->fs_info->free_chunk_space -= (stripe_size *
4767 map->num_stripes);
4768 spin_unlock(&extent_root->fs_info->free_chunk_lock);
4769
4770 free_extent_map(em);
4771 check_raid56_incompat_flag(extent_root->fs_info, type);
4772
4773 kfree(devices_info);
4774 return 0;
4775
4776 error_del_extent:
4777 write_lock(&em_tree->lock);
4778 remove_extent_mapping(em_tree, em);
4779 write_unlock(&em_tree->lock);
4780
4781 /* One for our allocation */
4782 free_extent_map(em);
4783 /* One for the tree reference */
4784 free_extent_map(em);
4785 /* One for the pending_chunks list reference */
4786 free_extent_map(em);
4787 error:
4788 kfree(devices_info);
4789 return ret;
4790 }
4791
4792 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
4793 struct btrfs_root *extent_root,
4794 u64 chunk_offset, u64 chunk_size)
4795 {
4796 struct btrfs_key key;
4797 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
4798 struct btrfs_device *device;
4799 struct btrfs_chunk *chunk;
4800 struct btrfs_stripe *stripe;
4801 struct extent_map_tree *em_tree;
4802 struct extent_map *em;
4803 struct map_lookup *map;
4804 size_t item_size;
4805 u64 dev_offset;
4806 u64 stripe_size;
4807 int i = 0;
4808 int ret;
4809
4810 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4811 read_lock(&em_tree->lock);
4812 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
4813 read_unlock(&em_tree->lock);
4814
4815 if (!em) {
4816 btrfs_crit(extent_root->fs_info, "unable to find logical "
4817 "%Lu len %Lu", chunk_offset, chunk_size);
4818 return -EINVAL;
4819 }
4820
4821 if (em->start != chunk_offset || em->len != chunk_size) {
4822 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted"
4823 " %Lu-%Lu, found %Lu-%Lu", chunk_offset,
4824 chunk_size, em->start, em->len);
4825 free_extent_map(em);
4826 return -EINVAL;
4827 }
4828
4829 map = (struct map_lookup *)em->bdev;
4830 item_size = btrfs_chunk_item_size(map->num_stripes);
4831 stripe_size = em->orig_block_len;
4832
4833 chunk = kzalloc(item_size, GFP_NOFS);
4834 if (!chunk) {
4835 ret = -ENOMEM;
4836 goto out;
4837 }
4838
4839 for (i = 0; i < map->num_stripes; i++) {
4840 device = map->stripes[i].dev;
4841 dev_offset = map->stripes[i].physical;
4842
4843 ret = btrfs_update_device(trans, device);
4844 if (ret)
4845 goto out;
4846 ret = btrfs_alloc_dev_extent(trans, device,
4847 chunk_root->root_key.objectid,
4848 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4849 chunk_offset, dev_offset,
4850 stripe_size);
4851 if (ret)
4852 goto out;
4853 }
4854
4855 stripe = &chunk->stripe;
4856 for (i = 0; i < map->num_stripes; i++) {
4857 device = map->stripes[i].dev;
4858 dev_offset = map->stripes[i].physical;
4859
4860 btrfs_set_stack_stripe_devid(stripe, device->devid);
4861 btrfs_set_stack_stripe_offset(stripe, dev_offset);
4862 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
4863 stripe++;
4864 }
4865
4866 btrfs_set_stack_chunk_length(chunk, chunk_size);
4867 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
4868 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
4869 btrfs_set_stack_chunk_type(chunk, map->type);
4870 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
4871 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
4872 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
4873 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
4874 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
4875
4876 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4877 key.type = BTRFS_CHUNK_ITEM_KEY;
4878 key.offset = chunk_offset;
4879
4880 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
4881 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
4882 /*
4883 * TODO: Cleanup of inserted chunk root in case of
4884 * failure.
4885 */
4886 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
4887 item_size);
4888 }
4889
4890 out:
4891 kfree(chunk);
4892 free_extent_map(em);
4893 return ret;
4894 }
4895
4896 /*
4897 * Chunk allocation falls into two parts. The first part does works
4898 * that make the new allocated chunk useable, but not do any operation
4899 * that modifies the chunk tree. The second part does the works that
4900 * require modifying the chunk tree. This division is important for the
4901 * bootstrap process of adding storage to a seed btrfs.
4902 */
4903 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4904 struct btrfs_root *extent_root, u64 type)
4905 {
4906 u64 chunk_offset;
4907
4908 ASSERT(mutex_is_locked(&extent_root->fs_info->chunk_mutex));
4909 chunk_offset = find_next_chunk(extent_root->fs_info);
4910 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type);
4911 }
4912
4913 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
4914 struct btrfs_root *root,
4915 struct btrfs_device *device)
4916 {
4917 u64 chunk_offset;
4918 u64 sys_chunk_offset;
4919 u64 alloc_profile;
4920 struct btrfs_fs_info *fs_info = root->fs_info;
4921 struct btrfs_root *extent_root = fs_info->extent_root;
4922 int ret;
4923
4924 chunk_offset = find_next_chunk(fs_info);
4925 alloc_profile = btrfs_get_alloc_profile(extent_root, 0);
4926 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset,
4927 alloc_profile);
4928 if (ret)
4929 return ret;
4930
4931 sys_chunk_offset = find_next_chunk(root->fs_info);
4932 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
4933 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset,
4934 alloc_profile);
4935 return ret;
4936 }
4937
4938 static inline int btrfs_chunk_max_errors(struct map_lookup *map)
4939 {
4940 int max_errors;
4941
4942 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
4943 BTRFS_BLOCK_GROUP_RAID10 |
4944 BTRFS_BLOCK_GROUP_RAID5 |
4945 BTRFS_BLOCK_GROUP_DUP)) {
4946 max_errors = 1;
4947 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
4948 max_errors = 2;
4949 } else {
4950 max_errors = 0;
4951 }
4952
4953 return max_errors;
4954 }
4955
4956 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
4957 {
4958 struct extent_map *em;
4959 struct map_lookup *map;
4960 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4961 int readonly = 0;
4962 int miss_ndevs = 0;
4963 int i;
4964
4965 read_lock(&map_tree->map_tree.lock);
4966 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
4967 read_unlock(&map_tree->map_tree.lock);
4968 if (!em)
4969 return 1;
4970
4971 map = (struct map_lookup *)em->bdev;
4972 for (i = 0; i < map->num_stripes; i++) {
4973 if (map->stripes[i].dev->missing) {
4974 miss_ndevs++;
4975 continue;
4976 }
4977
4978 if (!map->stripes[i].dev->writeable) {
4979 readonly = 1;
4980 goto end;
4981 }
4982 }
4983
4984 /*
4985 * If the number of missing devices is larger than max errors,
4986 * we can not write the data into that chunk successfully, so
4987 * set it readonly.
4988 */
4989 if (miss_ndevs > btrfs_chunk_max_errors(map))
4990 readonly = 1;
4991 end:
4992 free_extent_map(em);
4993 return readonly;
4994 }
4995
4996 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
4997 {
4998 extent_map_tree_init(&tree->map_tree);
4999 }
5000
5001 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
5002 {
5003 struct extent_map *em;
5004
5005 while (1) {
5006 write_lock(&tree->map_tree.lock);
5007 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
5008 if (em)
5009 remove_extent_mapping(&tree->map_tree, em);
5010 write_unlock(&tree->map_tree.lock);
5011 if (!em)
5012 break;
5013 /* once for us */
5014 free_extent_map(em);
5015 /* once for the tree */
5016 free_extent_map(em);
5017 }
5018 }
5019
5020 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
5021 {
5022 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
5023 struct extent_map *em;
5024 struct map_lookup *map;
5025 struct extent_map_tree *em_tree = &map_tree->map_tree;
5026 int ret;
5027
5028 read_lock(&em_tree->lock);
5029 em = lookup_extent_mapping(em_tree, logical, len);
5030 read_unlock(&em_tree->lock);
5031
5032 /*
5033 * We could return errors for these cases, but that could get ugly and
5034 * we'd probably do the same thing which is just not do anything else
5035 * and exit, so return 1 so the callers don't try to use other copies.
5036 */
5037 if (!em) {
5038 btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
5039 logical+len);
5040 return 1;
5041 }
5042
5043 if (em->start > logical || em->start + em->len < logical) {
5044 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got "
5045 "%Lu-%Lu", logical, logical+len, em->start,
5046 em->start + em->len);
5047 free_extent_map(em);
5048 return 1;
5049 }
5050
5051 map = (struct map_lookup *)em->bdev;
5052 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
5053 ret = map->num_stripes;
5054 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5055 ret = map->sub_stripes;
5056 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
5057 ret = 2;
5058 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5059 /*
5060 * There could be two corrupted data stripes, we need
5061 * to loop retry in order to rebuild the correct data.
5062 *
5063 * Fail a stripe at a time on every retry except the
5064 * stripe under reconstruction.
5065 */
5066 ret = map->num_stripes;
5067 else
5068 ret = 1;
5069 free_extent_map(em);
5070
5071 btrfs_dev_replace_lock(&fs_info->dev_replace);
5072 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
5073 ret++;
5074 btrfs_dev_replace_unlock(&fs_info->dev_replace);
5075
5076 return ret;
5077 }
5078
5079 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
5080 struct btrfs_mapping_tree *map_tree,
5081 u64 logical)
5082 {
5083 struct extent_map *em;
5084 struct map_lookup *map;
5085 struct extent_map_tree *em_tree = &map_tree->map_tree;
5086 unsigned long len = root->sectorsize;
5087
5088 read_lock(&em_tree->lock);
5089 em = lookup_extent_mapping(em_tree, logical, len);
5090 read_unlock(&em_tree->lock);
5091 BUG_ON(!em);
5092
5093 BUG_ON(em->start > logical || em->start + em->len < logical);
5094 map = (struct map_lookup *)em->bdev;
5095 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
5096 len = map->stripe_len * nr_data_stripes(map);
5097 free_extent_map(em);
5098 return len;
5099 }
5100
5101 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
5102 u64 logical, u64 len, int mirror_num)
5103 {
5104 struct extent_map *em;
5105 struct map_lookup *map;
5106 struct extent_map_tree *em_tree = &map_tree->map_tree;
5107 int ret = 0;
5108
5109 read_lock(&em_tree->lock);
5110 em = lookup_extent_mapping(em_tree, logical, len);
5111 read_unlock(&em_tree->lock);
5112 BUG_ON(!em);
5113
5114 BUG_ON(em->start > logical || em->start + em->len < logical);
5115 map = (struct map_lookup *)em->bdev;
5116 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
5117 ret = 1;
5118 free_extent_map(em);
5119 return ret;
5120 }
5121
5122 static int find_live_mirror(struct btrfs_fs_info *fs_info,
5123 struct map_lookup *map, int first, int num,
5124 int optimal, int dev_replace_is_ongoing)
5125 {
5126 int i;
5127 int tolerance;
5128 struct btrfs_device *srcdev;
5129
5130 if (dev_replace_is_ongoing &&
5131 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
5132 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
5133 srcdev = fs_info->dev_replace.srcdev;
5134 else
5135 srcdev = NULL;
5136
5137 /*
5138 * try to avoid the drive that is the source drive for a
5139 * dev-replace procedure, only choose it if no other non-missing
5140 * mirror is available
5141 */
5142 for (tolerance = 0; tolerance < 2; tolerance++) {
5143 if (map->stripes[optimal].dev->bdev &&
5144 (tolerance || map->stripes[optimal].dev != srcdev))
5145 return optimal;
5146 for (i = first; i < first + num; i++) {
5147 if (map->stripes[i].dev->bdev &&
5148 (tolerance || map->stripes[i].dev != srcdev))
5149 return i;
5150 }
5151 }
5152
5153 /* we couldn't find one that doesn't fail. Just return something
5154 * and the io error handling code will clean up eventually
5155 */
5156 return optimal;
5157 }
5158
5159 static inline int parity_smaller(u64 a, u64 b)
5160 {
5161 return a > b;
5162 }
5163
5164 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
5165 static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes)
5166 {
5167 struct btrfs_bio_stripe s;
5168 int i;
5169 u64 l;
5170 int again = 1;
5171
5172 while (again) {
5173 again = 0;
5174 for (i = 0; i < num_stripes - 1; i++) {
5175 if (parity_smaller(bbio->raid_map[i],
5176 bbio->raid_map[i+1])) {
5177 s = bbio->stripes[i];
5178 l = bbio->raid_map[i];
5179 bbio->stripes[i] = bbio->stripes[i+1];
5180 bbio->raid_map[i] = bbio->raid_map[i+1];
5181 bbio->stripes[i+1] = s;
5182 bbio->raid_map[i+1] = l;
5183
5184 again = 1;
5185 }
5186 }
5187 }
5188 }
5189
5190 static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
5191 {
5192 struct btrfs_bio *bbio = kzalloc(
5193 /* the size of the btrfs_bio */
5194 sizeof(struct btrfs_bio) +
5195 /* plus the variable array for the stripes */
5196 sizeof(struct btrfs_bio_stripe) * (total_stripes) +
5197 /* plus the variable array for the tgt dev */
5198 sizeof(int) * (real_stripes) +
5199 /*
5200 * plus the raid_map, which includes both the tgt dev
5201 * and the stripes
5202 */
5203 sizeof(u64) * (total_stripes),
5204 GFP_NOFS|__GFP_NOFAIL);
5205
5206 atomic_set(&bbio->error, 0);
5207 atomic_set(&bbio->refs, 1);
5208
5209 return bbio;
5210 }
5211
5212 void btrfs_get_bbio(struct btrfs_bio *bbio)
5213 {
5214 WARN_ON(!atomic_read(&bbio->refs));
5215 atomic_inc(&bbio->refs);
5216 }
5217
5218 void btrfs_put_bbio(struct btrfs_bio *bbio)
5219 {
5220 if (!bbio)
5221 return;
5222 if (atomic_dec_and_test(&bbio->refs))
5223 kfree(bbio);
5224 }
5225
5226 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5227 u64 logical, u64 *length,
5228 struct btrfs_bio **bbio_ret,
5229 int mirror_num, int need_raid_map)
5230 {
5231 struct extent_map *em;
5232 struct map_lookup *map;
5233 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
5234 struct extent_map_tree *em_tree = &map_tree->map_tree;
5235 u64 offset;
5236 u64 stripe_offset;
5237 u64 stripe_end_offset;
5238 u64 stripe_nr;
5239 u64 stripe_nr_orig;
5240 u64 stripe_nr_end;
5241 u64 stripe_len;
5242 u32 stripe_index;
5243 int i;
5244 int ret = 0;
5245 int num_stripes;
5246 int max_errors = 0;
5247 int tgtdev_indexes = 0;
5248 struct btrfs_bio *bbio = NULL;
5249 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
5250 int dev_replace_is_ongoing = 0;
5251 int num_alloc_stripes;
5252 int patch_the_first_stripe_for_dev_replace = 0;
5253 u64 physical_to_patch_in_first_stripe = 0;
5254 u64 raid56_full_stripe_start = (u64)-1;
5255
5256 read_lock(&em_tree->lock);
5257 em = lookup_extent_mapping(em_tree, logical, *length);
5258 read_unlock(&em_tree->lock);
5259
5260 if (!em) {
5261 btrfs_crit(fs_info, "unable to find logical %llu len %llu",
5262 logical, *length);
5263 return -EINVAL;
5264 }
5265
5266 if (em->start > logical || em->start + em->len < logical) {
5267 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, "
5268 "found %Lu-%Lu", logical, em->start,
5269 em->start + em->len);
5270 free_extent_map(em);
5271 return -EINVAL;
5272 }
5273
5274 map = (struct map_lookup *)em->bdev;
5275 offset = logical - em->start;
5276
5277 stripe_len = map->stripe_len;
5278 stripe_nr = offset;
5279 /*
5280 * stripe_nr counts the total number of stripes we have to stride
5281 * to get to this block
5282 */
5283 stripe_nr = div64_u64(stripe_nr, stripe_len);
5284
5285 stripe_offset = stripe_nr * stripe_len;
5286 BUG_ON(offset < stripe_offset);
5287
5288 /* stripe_offset is the offset of this block in its stripe*/
5289 stripe_offset = offset - stripe_offset;
5290
5291 /* if we're here for raid56, we need to know the stripe aligned start */
5292 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5293 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
5294 raid56_full_stripe_start = offset;
5295
5296 /* allow a write of a full stripe, but make sure we don't
5297 * allow straddling of stripes
5298 */
5299 raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
5300 full_stripe_len);
5301 raid56_full_stripe_start *= full_stripe_len;
5302 }
5303
5304 if (rw & REQ_DISCARD) {
5305 /* we don't discard raid56 yet */
5306 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5307 ret = -EOPNOTSUPP;
5308 goto out;
5309 }
5310 *length = min_t(u64, em->len - offset, *length);
5311 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
5312 u64 max_len;
5313 /* For writes to RAID[56], allow a full stripeset across all disks.
5314 For other RAID types and for RAID[56] reads, just allow a single
5315 stripe (on a single disk). */
5316 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
5317 (rw & REQ_WRITE)) {
5318 max_len = stripe_len * nr_data_stripes(map) -
5319 (offset - raid56_full_stripe_start);
5320 } else {
5321 /* we limit the length of each bio to what fits in a stripe */
5322 max_len = stripe_len - stripe_offset;
5323 }
5324 *length = min_t(u64, em->len - offset, max_len);
5325 } else {
5326 *length = em->len - offset;
5327 }
5328
5329 /* This is for when we're called from btrfs_merge_bio_hook() and all
5330 it cares about is the length */
5331 if (!bbio_ret)
5332 goto out;
5333
5334 btrfs_dev_replace_lock(dev_replace);
5335 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
5336 if (!dev_replace_is_ongoing)
5337 btrfs_dev_replace_unlock(dev_replace);
5338
5339 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
5340 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
5341 dev_replace->tgtdev != NULL) {
5342 /*
5343 * in dev-replace case, for repair case (that's the only
5344 * case where the mirror is selected explicitly when
5345 * calling btrfs_map_block), blocks left of the left cursor
5346 * can also be read from the target drive.
5347 * For REQ_GET_READ_MIRRORS, the target drive is added as
5348 * the last one to the array of stripes. For READ, it also
5349 * needs to be supported using the same mirror number.
5350 * If the requested block is not left of the left cursor,
5351 * EIO is returned. This can happen because btrfs_num_copies()
5352 * returns one more in the dev-replace case.
5353 */
5354 u64 tmp_length = *length;
5355 struct btrfs_bio *tmp_bbio = NULL;
5356 int tmp_num_stripes;
5357 u64 srcdev_devid = dev_replace->srcdev->devid;
5358 int index_srcdev = 0;
5359 int found = 0;
5360 u64 physical_of_found = 0;
5361
5362 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
5363 logical, &tmp_length, &tmp_bbio, 0, 0);
5364 if (ret) {
5365 WARN_ON(tmp_bbio != NULL);
5366 goto out;
5367 }
5368
5369 tmp_num_stripes = tmp_bbio->num_stripes;
5370 if (mirror_num > tmp_num_stripes) {
5371 /*
5372 * REQ_GET_READ_MIRRORS does not contain this
5373 * mirror, that means that the requested area
5374 * is not left of the left cursor
5375 */
5376 ret = -EIO;
5377 btrfs_put_bbio(tmp_bbio);
5378 goto out;
5379 }
5380
5381 /*
5382 * process the rest of the function using the mirror_num
5383 * of the source drive. Therefore look it up first.
5384 * At the end, patch the device pointer to the one of the
5385 * target drive.
5386 */
5387 for (i = 0; i < tmp_num_stripes; i++) {
5388 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) {
5389 /*
5390 * In case of DUP, in order to keep it
5391 * simple, only add the mirror with the
5392 * lowest physical address
5393 */
5394 if (found &&
5395 physical_of_found <=
5396 tmp_bbio->stripes[i].physical)
5397 continue;
5398 index_srcdev = i;
5399 found = 1;
5400 physical_of_found =
5401 tmp_bbio->stripes[i].physical;
5402 }
5403 }
5404
5405 if (found) {
5406 mirror_num = index_srcdev + 1;
5407 patch_the_first_stripe_for_dev_replace = 1;
5408 physical_to_patch_in_first_stripe = physical_of_found;
5409 } else {
5410 WARN_ON(1);
5411 ret = -EIO;
5412 btrfs_put_bbio(tmp_bbio);
5413 goto out;
5414 }
5415
5416 btrfs_put_bbio(tmp_bbio);
5417 } else if (mirror_num > map->num_stripes) {
5418 mirror_num = 0;
5419 }
5420
5421 num_stripes = 1;
5422 stripe_index = 0;
5423 stripe_nr_orig = stripe_nr;
5424 stripe_nr_end = ALIGN(offset + *length, map->stripe_len);
5425 stripe_nr_end = div_u64(stripe_nr_end, map->stripe_len);
5426 stripe_end_offset = stripe_nr_end * map->stripe_len -
5427 (offset + *length);
5428
5429 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5430 if (rw & REQ_DISCARD)
5431 num_stripes = min_t(u64, map->num_stripes,
5432 stripe_nr_end - stripe_nr_orig);
5433 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5434 &stripe_index);
5435 if (!(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)))
5436 mirror_num = 1;
5437 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
5438 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
5439 num_stripes = map->num_stripes;
5440 else if (mirror_num)
5441 stripe_index = mirror_num - 1;
5442 else {
5443 stripe_index = find_live_mirror(fs_info, map, 0,
5444 map->num_stripes,
5445 current->pid % map->num_stripes,
5446 dev_replace_is_ongoing);
5447 mirror_num = stripe_index + 1;
5448 }
5449
5450 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
5451 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
5452 num_stripes = map->num_stripes;
5453 } else if (mirror_num) {
5454 stripe_index = mirror_num - 1;
5455 } else {
5456 mirror_num = 1;
5457 }
5458
5459 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5460 u32 factor = map->num_stripes / map->sub_stripes;
5461
5462 stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
5463 stripe_index *= map->sub_stripes;
5464
5465 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5466 num_stripes = map->sub_stripes;
5467 else if (rw & REQ_DISCARD)
5468 num_stripes = min_t(u64, map->sub_stripes *
5469 (stripe_nr_end - stripe_nr_orig),
5470 map->num_stripes);
5471 else if (mirror_num)
5472 stripe_index += mirror_num - 1;
5473 else {
5474 int old_stripe_index = stripe_index;
5475 stripe_index = find_live_mirror(fs_info, map,
5476 stripe_index,
5477 map->sub_stripes, stripe_index +
5478 current->pid % map->sub_stripes,
5479 dev_replace_is_ongoing);
5480 mirror_num = stripe_index - old_stripe_index + 1;
5481 }
5482
5483 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5484 if (need_raid_map &&
5485 ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5486 mirror_num > 1)) {
5487 /* push stripe_nr back to the start of the full stripe */
5488 stripe_nr = div_u64(raid56_full_stripe_start,
5489 stripe_len * nr_data_stripes(map));
5490
5491 /* RAID[56] write or recovery. Return all stripes */
5492 num_stripes = map->num_stripes;
5493 max_errors = nr_parity_stripes(map);
5494
5495 *length = map->stripe_len;
5496 stripe_index = 0;
5497 stripe_offset = 0;
5498 } else {
5499 /*
5500 * Mirror #0 or #1 means the original data block.
5501 * Mirror #2 is RAID5 parity block.
5502 * Mirror #3 is RAID6 Q block.
5503 */
5504 stripe_nr = div_u64_rem(stripe_nr,
5505 nr_data_stripes(map), &stripe_index);
5506 if (mirror_num > 1)
5507 stripe_index = nr_data_stripes(map) +
5508 mirror_num - 2;
5509
5510 /* We distribute the parity blocks across stripes */
5511 div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
5512 &stripe_index);
5513 if (!(rw & (REQ_WRITE | REQ_DISCARD |
5514 REQ_GET_READ_MIRRORS)) && mirror_num <= 1)
5515 mirror_num = 1;
5516 }
5517 } else {
5518 /*
5519 * after this, stripe_nr is the number of stripes on this
5520 * device we have to walk to find the data, and stripe_index is
5521 * the number of our device in the stripe array
5522 */
5523 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5524 &stripe_index);
5525 mirror_num = stripe_index + 1;
5526 }
5527 BUG_ON(stripe_index >= map->num_stripes);
5528
5529 num_alloc_stripes = num_stripes;
5530 if (dev_replace_is_ongoing) {
5531 if (rw & (REQ_WRITE | REQ_DISCARD))
5532 num_alloc_stripes <<= 1;
5533 if (rw & REQ_GET_READ_MIRRORS)
5534 num_alloc_stripes++;
5535 tgtdev_indexes = num_stripes;
5536 }
5537
5538 bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes);
5539 if (!bbio) {
5540 ret = -ENOMEM;
5541 goto out;
5542 }
5543 if (dev_replace_is_ongoing)
5544 bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes);
5545
5546 /* build raid_map */
5547 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
5548 need_raid_map && ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5549 mirror_num > 1)) {
5550 u64 tmp;
5551 unsigned rot;
5552
5553 bbio->raid_map = (u64 *)((void *)bbio->stripes +
5554 sizeof(struct btrfs_bio_stripe) *
5555 num_alloc_stripes +
5556 sizeof(int) * tgtdev_indexes);
5557
5558 /* Work out the disk rotation on this stripe-set */
5559 div_u64_rem(stripe_nr, num_stripes, &rot);
5560
5561 /* Fill in the logical address of each stripe */
5562 tmp = stripe_nr * nr_data_stripes(map);
5563 for (i = 0; i < nr_data_stripes(map); i++)
5564 bbio->raid_map[(i+rot) % num_stripes] =
5565 em->start + (tmp + i) * map->stripe_len;
5566
5567 bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
5568 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5569 bbio->raid_map[(i+rot+1) % num_stripes] =
5570 RAID6_Q_STRIPE;
5571 }
5572
5573 if (rw & REQ_DISCARD) {
5574 u32 factor = 0;
5575 u32 sub_stripes = 0;
5576 u64 stripes_per_dev = 0;
5577 u32 remaining_stripes = 0;
5578 u32 last_stripe = 0;
5579
5580 if (map->type &
5581 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
5582 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5583 sub_stripes = 1;
5584 else
5585 sub_stripes = map->sub_stripes;
5586
5587 factor = map->num_stripes / sub_stripes;
5588 stripes_per_dev = div_u64_rem(stripe_nr_end -
5589 stripe_nr_orig,
5590 factor,
5591 &remaining_stripes);
5592 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
5593 last_stripe *= sub_stripes;
5594 }
5595
5596 for (i = 0; i < num_stripes; i++) {
5597 bbio->stripes[i].physical =
5598 map->stripes[stripe_index].physical +
5599 stripe_offset + stripe_nr * map->stripe_len;
5600 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
5601
5602 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
5603 BTRFS_BLOCK_GROUP_RAID10)) {
5604 bbio->stripes[i].length = stripes_per_dev *
5605 map->stripe_len;
5606
5607 if (i / sub_stripes < remaining_stripes)
5608 bbio->stripes[i].length +=
5609 map->stripe_len;
5610
5611 /*
5612 * Special for the first stripe and
5613 * the last stripe:
5614 *
5615 * |-------|...|-------|
5616 * |----------|
5617 * off end_off
5618 */
5619 if (i < sub_stripes)
5620 bbio->stripes[i].length -=
5621 stripe_offset;
5622
5623 if (stripe_index >= last_stripe &&
5624 stripe_index <= (last_stripe +
5625 sub_stripes - 1))
5626 bbio->stripes[i].length -=
5627 stripe_end_offset;
5628
5629 if (i == sub_stripes - 1)
5630 stripe_offset = 0;
5631 } else
5632 bbio->stripes[i].length = *length;
5633
5634 stripe_index++;
5635 if (stripe_index == map->num_stripes) {
5636 /* This could only happen for RAID0/10 */
5637 stripe_index = 0;
5638 stripe_nr++;
5639 }
5640 }
5641 } else {
5642 for (i = 0; i < num_stripes; i++) {
5643 bbio->stripes[i].physical =
5644 map->stripes[stripe_index].physical +
5645 stripe_offset +
5646 stripe_nr * map->stripe_len;
5647 bbio->stripes[i].dev =
5648 map->stripes[stripe_index].dev;
5649 stripe_index++;
5650 }
5651 }
5652
5653 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5654 max_errors = btrfs_chunk_max_errors(map);
5655
5656 if (bbio->raid_map)
5657 sort_parity_stripes(bbio, num_stripes);
5658
5659 tgtdev_indexes = 0;
5660 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
5661 dev_replace->tgtdev != NULL) {
5662 int index_where_to_add;
5663 u64 srcdev_devid = dev_replace->srcdev->devid;
5664
5665 /*
5666 * duplicate the write operations while the dev replace
5667 * procedure is running. Since the copying of the old disk
5668 * to the new disk takes place at run time while the
5669 * filesystem is mounted writable, the regular write
5670 * operations to the old disk have to be duplicated to go
5671 * to the new disk as well.
5672 * Note that device->missing is handled by the caller, and
5673 * that the write to the old disk is already set up in the
5674 * stripes array.
5675 */
5676 index_where_to_add = num_stripes;
5677 for (i = 0; i < num_stripes; i++) {
5678 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5679 /* write to new disk, too */
5680 struct btrfs_bio_stripe *new =
5681 bbio->stripes + index_where_to_add;
5682 struct btrfs_bio_stripe *old =
5683 bbio->stripes + i;
5684
5685 new->physical = old->physical;
5686 new->length = old->length;
5687 new->dev = dev_replace->tgtdev;
5688 bbio->tgtdev_map[i] = index_where_to_add;
5689 index_where_to_add++;
5690 max_errors++;
5691 tgtdev_indexes++;
5692 }
5693 }
5694 num_stripes = index_where_to_add;
5695 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
5696 dev_replace->tgtdev != NULL) {
5697 u64 srcdev_devid = dev_replace->srcdev->devid;
5698 int index_srcdev = 0;
5699 int found = 0;
5700 u64 physical_of_found = 0;
5701
5702 /*
5703 * During the dev-replace procedure, the target drive can
5704 * also be used to read data in case it is needed to repair
5705 * a corrupt block elsewhere. This is possible if the
5706 * requested area is left of the left cursor. In this area,
5707 * the target drive is a full copy of the source drive.
5708 */
5709 for (i = 0; i < num_stripes; i++) {
5710 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5711 /*
5712 * In case of DUP, in order to keep it
5713 * simple, only add the mirror with the
5714 * lowest physical address
5715 */
5716 if (found &&
5717 physical_of_found <=
5718 bbio->stripes[i].physical)
5719 continue;
5720 index_srcdev = i;
5721 found = 1;
5722 physical_of_found = bbio->stripes[i].physical;
5723 }
5724 }
5725 if (found) {
5726 if (physical_of_found + map->stripe_len <=
5727 dev_replace->cursor_left) {
5728 struct btrfs_bio_stripe *tgtdev_stripe =
5729 bbio->stripes + num_stripes;
5730
5731 tgtdev_stripe->physical = physical_of_found;
5732 tgtdev_stripe->length =
5733 bbio->stripes[index_srcdev].length;
5734 tgtdev_stripe->dev = dev_replace->tgtdev;
5735 bbio->tgtdev_map[index_srcdev] = num_stripes;
5736
5737 tgtdev_indexes++;
5738 num_stripes++;
5739 }
5740 }
5741 }
5742
5743 *bbio_ret = bbio;
5744 bbio->map_type = map->type;
5745 bbio->num_stripes = num_stripes;
5746 bbio->max_errors = max_errors;
5747 bbio->mirror_num = mirror_num;
5748 bbio->num_tgtdevs = tgtdev_indexes;
5749
5750 /*
5751 * this is the case that REQ_READ && dev_replace_is_ongoing &&
5752 * mirror_num == num_stripes + 1 && dev_replace target drive is
5753 * available as a mirror
5754 */
5755 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
5756 WARN_ON(num_stripes > 1);
5757 bbio->stripes[0].dev = dev_replace->tgtdev;
5758 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
5759 bbio->mirror_num = map->num_stripes + 1;
5760 }
5761 out:
5762 if (dev_replace_is_ongoing)
5763 btrfs_dev_replace_unlock(dev_replace);
5764 free_extent_map(em);
5765 return ret;
5766 }
5767
5768 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5769 u64 logical, u64 *length,
5770 struct btrfs_bio **bbio_ret, int mirror_num)
5771 {
5772 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5773 mirror_num, 0);
5774 }
5775
5776 /* For Scrub/replace */
5777 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
5778 u64 logical, u64 *length,
5779 struct btrfs_bio **bbio_ret, int mirror_num,
5780 int need_raid_map)
5781 {
5782 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5783 mirror_num, need_raid_map);
5784 }
5785
5786 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
5787 u64 chunk_start, u64 physical, u64 devid,
5788 u64 **logical, int *naddrs, int *stripe_len)
5789 {
5790 struct extent_map_tree *em_tree = &map_tree->map_tree;
5791 struct extent_map *em;
5792 struct map_lookup *map;
5793 u64 *buf;
5794 u64 bytenr;
5795 u64 length;
5796 u64 stripe_nr;
5797 u64 rmap_len;
5798 int i, j, nr = 0;
5799
5800 read_lock(&em_tree->lock);
5801 em = lookup_extent_mapping(em_tree, chunk_start, 1);
5802 read_unlock(&em_tree->lock);
5803
5804 if (!em) {
5805 printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
5806 chunk_start);
5807 return -EIO;
5808 }
5809
5810 if (em->start != chunk_start) {
5811 printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
5812 em->start, chunk_start);
5813 free_extent_map(em);
5814 return -EIO;
5815 }
5816 map = (struct map_lookup *)em->bdev;
5817
5818 length = em->len;
5819 rmap_len = map->stripe_len;
5820
5821 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5822 length = div_u64(length, map->num_stripes / map->sub_stripes);
5823 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5824 length = div_u64(length, map->num_stripes);
5825 else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5826 length = div_u64(length, nr_data_stripes(map));
5827 rmap_len = map->stripe_len * nr_data_stripes(map);
5828 }
5829
5830 buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
5831 BUG_ON(!buf); /* -ENOMEM */
5832
5833 for (i = 0; i < map->num_stripes; i++) {
5834 if (devid && map->stripes[i].dev->devid != devid)
5835 continue;
5836 if (map->stripes[i].physical > physical ||
5837 map->stripes[i].physical + length <= physical)
5838 continue;
5839
5840 stripe_nr = physical - map->stripes[i].physical;
5841 stripe_nr = div_u64(stripe_nr, map->stripe_len);
5842
5843 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5844 stripe_nr = stripe_nr * map->num_stripes + i;
5845 stripe_nr = div_u64(stripe_nr, map->sub_stripes);
5846 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5847 stripe_nr = stripe_nr * map->num_stripes + i;
5848 } /* else if RAID[56], multiply by nr_data_stripes().
5849 * Alternatively, just use rmap_len below instead of
5850 * map->stripe_len */
5851
5852 bytenr = chunk_start + stripe_nr * rmap_len;
5853 WARN_ON(nr >= map->num_stripes);
5854 for (j = 0; j < nr; j++) {
5855 if (buf[j] == bytenr)
5856 break;
5857 }
5858 if (j == nr) {
5859 WARN_ON(nr >= map->num_stripes);
5860 buf[nr++] = bytenr;
5861 }
5862 }
5863
5864 *logical = buf;
5865 *naddrs = nr;
5866 *stripe_len = rmap_len;
5867
5868 free_extent_map(em);
5869 return 0;
5870 }
5871
5872 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio)
5873 {
5874 bio->bi_private = bbio->private;
5875 bio->bi_end_io = bbio->end_io;
5876 bio_endio(bio);
5877
5878 btrfs_put_bbio(bbio);
5879 }
5880
5881 static void btrfs_end_bio(struct bio *bio)
5882 {
5883 struct btrfs_bio *bbio = bio->bi_private;
5884 int is_orig_bio = 0;
5885
5886 if (bio->bi_error) {
5887 atomic_inc(&bbio->error);
5888 if (bio->bi_error == -EIO || bio->bi_error == -EREMOTEIO) {
5889 unsigned int stripe_index =
5890 btrfs_io_bio(bio)->stripe_index;
5891 struct btrfs_device *dev;
5892
5893 BUG_ON(stripe_index >= bbio->num_stripes);
5894 dev = bbio->stripes[stripe_index].dev;
5895 if (dev->bdev) {
5896 if (bio->bi_rw & WRITE)
5897 btrfs_dev_stat_inc(dev,
5898 BTRFS_DEV_STAT_WRITE_ERRS);
5899 else
5900 btrfs_dev_stat_inc(dev,
5901 BTRFS_DEV_STAT_READ_ERRS);
5902 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
5903 btrfs_dev_stat_inc(dev,
5904 BTRFS_DEV_STAT_FLUSH_ERRS);
5905 btrfs_dev_stat_print_on_error(dev);
5906 }
5907 }
5908 }
5909
5910 if (bio == bbio->orig_bio)
5911 is_orig_bio = 1;
5912
5913 btrfs_bio_counter_dec(bbio->fs_info);
5914
5915 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5916 if (!is_orig_bio) {
5917 bio_put(bio);
5918 bio = bbio->orig_bio;
5919 }
5920
5921 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5922 /* only send an error to the higher layers if it is
5923 * beyond the tolerance of the btrfs bio
5924 */
5925 if (atomic_read(&bbio->error) > bbio->max_errors) {
5926 bio->bi_error = -EIO;
5927 } else {
5928 /*
5929 * this bio is actually up to date, we didn't
5930 * go over the max number of errors
5931 */
5932 bio->bi_error = 0;
5933 }
5934
5935 btrfs_end_bbio(bbio, bio);
5936 } else if (!is_orig_bio) {
5937 bio_put(bio);
5938 }
5939 }
5940
5941 /*
5942 * see run_scheduled_bios for a description of why bios are collected for
5943 * async submit.
5944 *
5945 * This will add one bio to the pending list for a device and make sure
5946 * the work struct is scheduled.
5947 */
5948 static noinline void btrfs_schedule_bio(struct btrfs_root *root,
5949 struct btrfs_device *device,
5950 int rw, struct bio *bio)
5951 {
5952 int should_queue = 1;
5953 struct btrfs_pending_bios *pending_bios;
5954
5955 if (device->missing || !device->bdev) {
5956 bio_io_error(bio);
5957 return;
5958 }
5959
5960 /* don't bother with additional async steps for reads, right now */
5961 if (!(rw & REQ_WRITE)) {
5962 bio_get(bio);
5963 btrfsic_submit_bio(rw, bio);
5964 bio_put(bio);
5965 return;
5966 }
5967
5968 /*
5969 * nr_async_bios allows us to reliably return congestion to the
5970 * higher layers. Otherwise, the async bio makes it appear we have
5971 * made progress against dirty pages when we've really just put it
5972 * on a queue for later
5973 */
5974 atomic_inc(&root->fs_info->nr_async_bios);
5975 WARN_ON(bio->bi_next);
5976 bio->bi_next = NULL;
5977 bio->bi_rw |= rw;
5978
5979 spin_lock(&device->io_lock);
5980 if (bio->bi_rw & REQ_SYNC)
5981 pending_bios = &device->pending_sync_bios;
5982 else
5983 pending_bios = &device->pending_bios;
5984
5985 if (pending_bios->tail)
5986 pending_bios->tail->bi_next = bio;
5987
5988 pending_bios->tail = bio;
5989 if (!pending_bios->head)
5990 pending_bios->head = bio;
5991 if (device->running_pending)
5992 should_queue = 0;
5993
5994 spin_unlock(&device->io_lock);
5995
5996 if (should_queue)
5997 btrfs_queue_work(root->fs_info->submit_workers,
5998 &device->work);
5999 }
6000
6001 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
6002 struct bio *bio, u64 physical, int dev_nr,
6003 int rw, int async)
6004 {
6005 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
6006
6007 bio->bi_private = bbio;
6008 btrfs_io_bio(bio)->stripe_index = dev_nr;
6009 bio->bi_end_io = btrfs_end_bio;
6010 bio->bi_iter.bi_sector = physical >> 9;
6011 #ifdef DEBUG
6012 {
6013 struct rcu_string *name;
6014
6015 rcu_read_lock();
6016 name = rcu_dereference(dev->name);
6017 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
6018 "(%s id %llu), size=%u\n", rw,
6019 (u64)bio->bi_iter.bi_sector, (u_long)dev->bdev->bd_dev,
6020 name->str, dev->devid, bio->bi_iter.bi_size);
6021 rcu_read_unlock();
6022 }
6023 #endif
6024 bio->bi_bdev = dev->bdev;
6025
6026 btrfs_bio_counter_inc_noblocked(root->fs_info);
6027
6028 if (async)
6029 btrfs_schedule_bio(root, dev, rw, bio);
6030 else
6031 btrfsic_submit_bio(rw, bio);
6032 }
6033
6034 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
6035 {
6036 atomic_inc(&bbio->error);
6037 if (atomic_dec_and_test(&bbio->stripes_pending)) {
6038 /* Shoud be the original bio. */
6039 WARN_ON(bio != bbio->orig_bio);
6040
6041 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
6042 bio->bi_iter.bi_sector = logical >> 9;
6043 bio->bi_error = -EIO;
6044 btrfs_end_bbio(bbio, bio);
6045 }
6046 }
6047
6048 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
6049 int mirror_num, int async_submit)
6050 {
6051 struct btrfs_device *dev;
6052 struct bio *first_bio = bio;
6053 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
6054 u64 length = 0;
6055 u64 map_length;
6056 int ret;
6057 int dev_nr;
6058 int total_devs;
6059 struct btrfs_bio *bbio = NULL;
6060
6061 length = bio->bi_iter.bi_size;
6062 map_length = length;
6063
6064 btrfs_bio_counter_inc_blocked(root->fs_info);
6065 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
6066 mirror_num, 1);
6067 if (ret) {
6068 btrfs_bio_counter_dec(root->fs_info);
6069 return ret;
6070 }
6071
6072 total_devs = bbio->num_stripes;
6073 bbio->orig_bio = first_bio;
6074 bbio->private = first_bio->bi_private;
6075 bbio->end_io = first_bio->bi_end_io;
6076 bbio->fs_info = root->fs_info;
6077 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
6078
6079 if (bbio->raid_map) {
6080 /* In this case, map_length has been set to the length of
6081 a single stripe; not the whole write */
6082 if (rw & WRITE) {
6083 ret = raid56_parity_write(root, bio, bbio, map_length);
6084 } else {
6085 ret = raid56_parity_recover(root, bio, bbio, map_length,
6086 mirror_num, 1);
6087 }
6088
6089 btrfs_bio_counter_dec(root->fs_info);
6090 return ret;
6091 }
6092
6093 if (map_length < length) {
6094 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
6095 logical, length, map_length);
6096 BUG();
6097 }
6098
6099 for (dev_nr = 0; dev_nr < total_devs; dev_nr++) {
6100 dev = bbio->stripes[dev_nr].dev;
6101 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
6102 bbio_error(bbio, first_bio, logical);
6103 continue;
6104 }
6105
6106 if (dev_nr < total_devs - 1) {
6107 bio = btrfs_bio_clone(first_bio, GFP_NOFS);
6108 BUG_ON(!bio); /* -ENOMEM */
6109 } else
6110 bio = first_bio;
6111
6112 submit_stripe_bio(root, bbio, bio,
6113 bbio->stripes[dev_nr].physical, dev_nr, rw,
6114 async_submit);
6115 }
6116 btrfs_bio_counter_dec(root->fs_info);
6117 return 0;
6118 }
6119
6120 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
6121 u8 *uuid, u8 *fsid)
6122 {
6123 struct btrfs_device *device;
6124 struct btrfs_fs_devices *cur_devices;
6125
6126 cur_devices = fs_info->fs_devices;
6127 while (cur_devices) {
6128 if (!fsid ||
6129 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
6130 device = __find_device(&cur_devices->devices,
6131 devid, uuid);
6132 if (device)
6133 return device;
6134 }
6135 cur_devices = cur_devices->seed;
6136 }
6137 return NULL;
6138 }
6139
6140 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
6141 struct btrfs_fs_devices *fs_devices,
6142 u64 devid, u8 *dev_uuid)
6143 {
6144 struct btrfs_device *device;
6145
6146 device = btrfs_alloc_device(NULL, &devid, dev_uuid);
6147 if (IS_ERR(device))
6148 return NULL;
6149
6150 list_add(&device->dev_list, &fs_devices->devices);
6151 device->fs_devices = fs_devices;
6152 fs_devices->num_devices++;
6153
6154 device->missing = 1;
6155 fs_devices->missing_devices++;
6156
6157 return device;
6158 }
6159
6160 /**
6161 * btrfs_alloc_device - allocate struct btrfs_device
6162 * @fs_info: used only for generating a new devid, can be NULL if
6163 * devid is provided (i.e. @devid != NULL).
6164 * @devid: a pointer to devid for this device. If NULL a new devid
6165 * is generated.
6166 * @uuid: a pointer to UUID for this device. If NULL a new UUID
6167 * is generated.
6168 *
6169 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
6170 * on error. Returned struct is not linked onto any lists and can be
6171 * destroyed with kfree() right away.
6172 */
6173 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
6174 const u64 *devid,
6175 const u8 *uuid)
6176 {
6177 struct btrfs_device *dev;
6178 u64 tmp;
6179
6180 if (WARN_ON(!devid && !fs_info))
6181 return ERR_PTR(-EINVAL);
6182
6183 dev = __alloc_device();
6184 if (IS_ERR(dev))
6185 return dev;
6186
6187 if (devid)
6188 tmp = *devid;
6189 else {
6190 int ret;
6191
6192 ret = find_next_devid(fs_info, &tmp);
6193 if (ret) {
6194 kfree(dev);
6195 return ERR_PTR(ret);
6196 }
6197 }
6198 dev->devid = tmp;
6199
6200 if (uuid)
6201 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
6202 else
6203 generate_random_uuid(dev->uuid);
6204
6205 btrfs_init_work(&dev->work, btrfs_submit_helper,
6206 pending_bios_fn, NULL, NULL);
6207
6208 return dev;
6209 }
6210
6211 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
6212 struct extent_buffer *leaf,
6213 struct btrfs_chunk *chunk)
6214 {
6215 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
6216 struct map_lookup *map;
6217 struct extent_map *em;
6218 u64 logical;
6219 u64 length;
6220 u64 devid;
6221 u8 uuid[BTRFS_UUID_SIZE];
6222 int num_stripes;
6223 int ret;
6224 int i;
6225
6226 logical = key->offset;
6227 length = btrfs_chunk_length(leaf, chunk);
6228
6229 read_lock(&map_tree->map_tree.lock);
6230 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
6231 read_unlock(&map_tree->map_tree.lock);
6232
6233 /* already mapped? */
6234 if (em && em->start <= logical && em->start + em->len > logical) {
6235 free_extent_map(em);
6236 return 0;
6237 } else if (em) {
6238 free_extent_map(em);
6239 }
6240
6241 em = alloc_extent_map();
6242 if (!em)
6243 return -ENOMEM;
6244 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
6245 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
6246 if (!map) {
6247 free_extent_map(em);
6248 return -ENOMEM;
6249 }
6250
6251 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
6252 em->bdev = (struct block_device *)map;
6253 em->start = logical;
6254 em->len = length;
6255 em->orig_start = 0;
6256 em->block_start = 0;
6257 em->block_len = em->len;
6258
6259 map->num_stripes = num_stripes;
6260 map->io_width = btrfs_chunk_io_width(leaf, chunk);
6261 map->io_align = btrfs_chunk_io_align(leaf, chunk);
6262 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
6263 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6264 map->type = btrfs_chunk_type(leaf, chunk);
6265 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
6266 for (i = 0; i < num_stripes; i++) {
6267 map->stripes[i].physical =
6268 btrfs_stripe_offset_nr(leaf, chunk, i);
6269 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
6270 read_extent_buffer(leaf, uuid, (unsigned long)
6271 btrfs_stripe_dev_uuid_nr(chunk, i),
6272 BTRFS_UUID_SIZE);
6273 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
6274 uuid, NULL);
6275 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
6276 free_extent_map(em);
6277 return -EIO;
6278 }
6279 if (!map->stripes[i].dev) {
6280 map->stripes[i].dev =
6281 add_missing_dev(root, root->fs_info->fs_devices,
6282 devid, uuid);
6283 if (!map->stripes[i].dev) {
6284 free_extent_map(em);
6285 return -EIO;
6286 }
6287 btrfs_warn(root->fs_info, "devid %llu uuid %pU is missing",
6288 devid, uuid);
6289 }
6290 map->stripes[i].dev->in_fs_metadata = 1;
6291 }
6292
6293 write_lock(&map_tree->map_tree.lock);
6294 ret = add_extent_mapping(&map_tree->map_tree, em, 0);
6295 write_unlock(&map_tree->map_tree.lock);
6296 BUG_ON(ret); /* Tree corruption */
6297 free_extent_map(em);
6298
6299 return 0;
6300 }
6301
6302 static void fill_device_from_item(struct extent_buffer *leaf,
6303 struct btrfs_dev_item *dev_item,
6304 struct btrfs_device *device)
6305 {
6306 unsigned long ptr;
6307
6308 device->devid = btrfs_device_id(leaf, dev_item);
6309 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
6310 device->total_bytes = device->disk_total_bytes;
6311 device->commit_total_bytes = device->disk_total_bytes;
6312 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
6313 device->commit_bytes_used = device->bytes_used;
6314 device->type = btrfs_device_type(leaf, dev_item);
6315 device->io_align = btrfs_device_io_align(leaf, dev_item);
6316 device->io_width = btrfs_device_io_width(leaf, dev_item);
6317 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
6318 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
6319 device->is_tgtdev_for_dev_replace = 0;
6320
6321 ptr = btrfs_device_uuid(dev_item);
6322 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
6323 }
6324
6325 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_root *root,
6326 u8 *fsid)
6327 {
6328 struct btrfs_fs_devices *fs_devices;
6329 int ret;
6330
6331 BUG_ON(!mutex_is_locked(&uuid_mutex));
6332
6333 fs_devices = root->fs_info->fs_devices->seed;
6334 while (fs_devices) {
6335 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE))
6336 return fs_devices;
6337
6338 fs_devices = fs_devices->seed;
6339 }
6340
6341 fs_devices = find_fsid(fsid);
6342 if (!fs_devices) {
6343 if (!btrfs_test_opt(root, DEGRADED))
6344 return ERR_PTR(-ENOENT);
6345
6346 fs_devices = alloc_fs_devices(fsid);
6347 if (IS_ERR(fs_devices))
6348 return fs_devices;
6349
6350 fs_devices->seeding = 1;
6351 fs_devices->opened = 1;
6352 return fs_devices;
6353 }
6354
6355 fs_devices = clone_fs_devices(fs_devices);
6356 if (IS_ERR(fs_devices))
6357 return fs_devices;
6358
6359 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
6360 root->fs_info->bdev_holder);
6361 if (ret) {
6362 free_fs_devices(fs_devices);
6363 fs_devices = ERR_PTR(ret);
6364 goto out;
6365 }
6366
6367 if (!fs_devices->seeding) {
6368 __btrfs_close_devices(fs_devices);
6369 free_fs_devices(fs_devices);
6370 fs_devices = ERR_PTR(-EINVAL);
6371 goto out;
6372 }
6373
6374 fs_devices->seed = root->fs_info->fs_devices->seed;
6375 root->fs_info->fs_devices->seed = fs_devices;
6376 out:
6377 return fs_devices;
6378 }
6379
6380 static int read_one_dev(struct btrfs_root *root,
6381 struct extent_buffer *leaf,
6382 struct btrfs_dev_item *dev_item)
6383 {
6384 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6385 struct btrfs_device *device;
6386 u64 devid;
6387 int ret;
6388 u8 fs_uuid[BTRFS_UUID_SIZE];
6389 u8 dev_uuid[BTRFS_UUID_SIZE];
6390
6391 devid = btrfs_device_id(leaf, dev_item);
6392 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
6393 BTRFS_UUID_SIZE);
6394 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
6395 BTRFS_UUID_SIZE);
6396
6397 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
6398 fs_devices = open_seed_devices(root, fs_uuid);
6399 if (IS_ERR(fs_devices))
6400 return PTR_ERR(fs_devices);
6401 }
6402
6403 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
6404 if (!device) {
6405 if (!btrfs_test_opt(root, DEGRADED))
6406 return -EIO;
6407
6408 device = add_missing_dev(root, fs_devices, devid, dev_uuid);
6409 if (!device)
6410 return -ENOMEM;
6411 btrfs_warn(root->fs_info, "devid %llu uuid %pU missing",
6412 devid, dev_uuid);
6413 } else {
6414 if (!device->bdev && !btrfs_test_opt(root, DEGRADED))
6415 return -EIO;
6416
6417 if(!device->bdev && !device->missing) {
6418 /*
6419 * this happens when a device that was properly setup
6420 * in the device info lists suddenly goes bad.
6421 * device->bdev is NULL, and so we have to set
6422 * device->missing to one here
6423 */
6424 device->fs_devices->missing_devices++;
6425 device->missing = 1;
6426 }
6427
6428 /* Move the device to its own fs_devices */
6429 if (device->fs_devices != fs_devices) {
6430 ASSERT(device->missing);
6431
6432 list_move(&device->dev_list, &fs_devices->devices);
6433 device->fs_devices->num_devices--;
6434 fs_devices->num_devices++;
6435
6436 device->fs_devices->missing_devices--;
6437 fs_devices->missing_devices++;
6438
6439 device->fs_devices = fs_devices;
6440 }
6441 }
6442
6443 if (device->fs_devices != root->fs_info->fs_devices) {
6444 BUG_ON(device->writeable);
6445 if (device->generation !=
6446 btrfs_device_generation(leaf, dev_item))
6447 return -EINVAL;
6448 }
6449
6450 fill_device_from_item(leaf, dev_item, device);
6451 device->in_fs_metadata = 1;
6452 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
6453 device->fs_devices->total_rw_bytes += device->total_bytes;
6454 spin_lock(&root->fs_info->free_chunk_lock);
6455 root->fs_info->free_chunk_space += device->total_bytes -
6456 device->bytes_used;
6457 spin_unlock(&root->fs_info->free_chunk_lock);
6458 }
6459 ret = 0;
6460 return ret;
6461 }
6462
6463 int btrfs_read_sys_array(struct btrfs_root *root)
6464 {
6465 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
6466 struct extent_buffer *sb;
6467 struct btrfs_disk_key *disk_key;
6468 struct btrfs_chunk *chunk;
6469 u8 *array_ptr;
6470 unsigned long sb_array_offset;
6471 int ret = 0;
6472 u32 num_stripes;
6473 u32 array_size;
6474 u32 len = 0;
6475 u32 cur_offset;
6476 struct btrfs_key key;
6477
6478 ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
6479 /*
6480 * This will create extent buffer of nodesize, superblock size is
6481 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
6482 * overallocate but we can keep it as-is, only the first page is used.
6483 */
6484 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
6485 if (!sb)
6486 return -ENOMEM;
6487 btrfs_set_buffer_uptodate(sb);
6488 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
6489 /*
6490 * The sb extent buffer is artifical and just used to read the system array.
6491 * btrfs_set_buffer_uptodate() call does not properly mark all it's
6492 * pages up-to-date when the page is larger: extent does not cover the
6493 * whole page and consequently check_page_uptodate does not find all
6494 * the page's extents up-to-date (the hole beyond sb),
6495 * write_extent_buffer then triggers a WARN_ON.
6496 *
6497 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
6498 * but sb spans only this function. Add an explicit SetPageUptodate call
6499 * to silence the warning eg. on PowerPC 64.
6500 */
6501 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
6502 SetPageUptodate(sb->pages[0]);
6503
6504 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
6505 array_size = btrfs_super_sys_array_size(super_copy);
6506
6507 array_ptr = super_copy->sys_chunk_array;
6508 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
6509 cur_offset = 0;
6510
6511 while (cur_offset < array_size) {
6512 disk_key = (struct btrfs_disk_key *)array_ptr;
6513 len = sizeof(*disk_key);
6514 if (cur_offset + len > array_size)
6515 goto out_short_read;
6516
6517 btrfs_disk_key_to_cpu(&key, disk_key);
6518
6519 array_ptr += len;
6520 sb_array_offset += len;
6521 cur_offset += len;
6522
6523 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6524 chunk = (struct btrfs_chunk *)sb_array_offset;
6525 /*
6526 * At least one btrfs_chunk with one stripe must be
6527 * present, exact stripe count check comes afterwards
6528 */
6529 len = btrfs_chunk_item_size(1);
6530 if (cur_offset + len > array_size)
6531 goto out_short_read;
6532
6533 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
6534 if (!num_stripes) {
6535 printk(KERN_ERR
6536 "BTRFS: invalid number of stripes %u in sys_array at offset %u\n",
6537 num_stripes, cur_offset);
6538 ret = -EIO;
6539 break;
6540 }
6541
6542 len = btrfs_chunk_item_size(num_stripes);
6543 if (cur_offset + len > array_size)
6544 goto out_short_read;
6545
6546 ret = read_one_chunk(root, &key, sb, chunk);
6547 if (ret)
6548 break;
6549 } else {
6550 ret = -EIO;
6551 break;
6552 }
6553 array_ptr += len;
6554 sb_array_offset += len;
6555 cur_offset += len;
6556 }
6557 free_extent_buffer(sb);
6558 return ret;
6559
6560 out_short_read:
6561 printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
6562 len, cur_offset);
6563 free_extent_buffer(sb);
6564 return -EIO;
6565 }
6566
6567 int btrfs_read_chunk_tree(struct btrfs_root *root)
6568 {
6569 struct btrfs_path *path;
6570 struct extent_buffer *leaf;
6571 struct btrfs_key key;
6572 struct btrfs_key found_key;
6573 int ret;
6574 int slot;
6575
6576 root = root->fs_info->chunk_root;
6577
6578 path = btrfs_alloc_path();
6579 if (!path)
6580 return -ENOMEM;
6581
6582 mutex_lock(&uuid_mutex);
6583 lock_chunks(root);
6584
6585 /*
6586 * Read all device items, and then all the chunk items. All
6587 * device items are found before any chunk item (their object id
6588 * is smaller than the lowest possible object id for a chunk
6589 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
6590 */
6591 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
6592 key.offset = 0;
6593 key.type = 0;
6594 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6595 if (ret < 0)
6596 goto error;
6597 while (1) {
6598 leaf = path->nodes[0];
6599 slot = path->slots[0];
6600 if (slot >= btrfs_header_nritems(leaf)) {
6601 ret = btrfs_next_leaf(root, path);
6602 if (ret == 0)
6603 continue;
6604 if (ret < 0)
6605 goto error;
6606 break;
6607 }
6608 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6609 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
6610 struct btrfs_dev_item *dev_item;
6611 dev_item = btrfs_item_ptr(leaf, slot,
6612 struct btrfs_dev_item);
6613 ret = read_one_dev(root, leaf, dev_item);
6614 if (ret)
6615 goto error;
6616 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
6617 struct btrfs_chunk *chunk;
6618 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
6619 ret = read_one_chunk(root, &found_key, leaf, chunk);
6620 if (ret)
6621 goto error;
6622 }
6623 path->slots[0]++;
6624 }
6625 ret = 0;
6626 error:
6627 unlock_chunks(root);
6628 mutex_unlock(&uuid_mutex);
6629
6630 btrfs_free_path(path);
6631 return ret;
6632 }
6633
6634 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
6635 {
6636 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6637 struct btrfs_device *device;
6638
6639 while (fs_devices) {
6640 mutex_lock(&fs_devices->device_list_mutex);
6641 list_for_each_entry(device, &fs_devices->devices, dev_list)
6642 device->dev_root = fs_info->dev_root;
6643 mutex_unlock(&fs_devices->device_list_mutex);
6644
6645 fs_devices = fs_devices->seed;
6646 }
6647 }
6648
6649 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
6650 {
6651 int i;
6652
6653 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6654 btrfs_dev_stat_reset(dev, i);
6655 }
6656
6657 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
6658 {
6659 struct btrfs_key key;
6660 struct btrfs_key found_key;
6661 struct btrfs_root *dev_root = fs_info->dev_root;
6662 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6663 struct extent_buffer *eb;
6664 int slot;
6665 int ret = 0;
6666 struct btrfs_device *device;
6667 struct btrfs_path *path = NULL;
6668 int i;
6669
6670 path = btrfs_alloc_path();
6671 if (!path) {
6672 ret = -ENOMEM;
6673 goto out;
6674 }
6675
6676 mutex_lock(&fs_devices->device_list_mutex);
6677 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6678 int item_size;
6679 struct btrfs_dev_stats_item *ptr;
6680
6681 key.objectid = 0;
6682 key.type = BTRFS_DEV_STATS_KEY;
6683 key.offset = device->devid;
6684 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
6685 if (ret) {
6686 __btrfs_reset_dev_stats(device);
6687 device->dev_stats_valid = 1;
6688 btrfs_release_path(path);
6689 continue;
6690 }
6691 slot = path->slots[0];
6692 eb = path->nodes[0];
6693 btrfs_item_key_to_cpu(eb, &found_key, slot);
6694 item_size = btrfs_item_size_nr(eb, slot);
6695
6696 ptr = btrfs_item_ptr(eb, slot,
6697 struct btrfs_dev_stats_item);
6698
6699 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6700 if (item_size >= (1 + i) * sizeof(__le64))
6701 btrfs_dev_stat_set(device, i,
6702 btrfs_dev_stats_value(eb, ptr, i));
6703 else
6704 btrfs_dev_stat_reset(device, i);
6705 }
6706
6707 device->dev_stats_valid = 1;
6708 btrfs_dev_stat_print_on_load(device);
6709 btrfs_release_path(path);
6710 }
6711 mutex_unlock(&fs_devices->device_list_mutex);
6712
6713 out:
6714 btrfs_free_path(path);
6715 return ret < 0 ? ret : 0;
6716 }
6717
6718 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
6719 struct btrfs_root *dev_root,
6720 struct btrfs_device *device)
6721 {
6722 struct btrfs_path *path;
6723 struct btrfs_key key;
6724 struct extent_buffer *eb;
6725 struct btrfs_dev_stats_item *ptr;
6726 int ret;
6727 int i;
6728
6729 key.objectid = 0;
6730 key.type = BTRFS_DEV_STATS_KEY;
6731 key.offset = device->devid;
6732
6733 path = btrfs_alloc_path();
6734 BUG_ON(!path);
6735 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
6736 if (ret < 0) {
6737 btrfs_warn_in_rcu(dev_root->fs_info,
6738 "error %d while searching for dev_stats item for device %s",
6739 ret, rcu_str_deref(device->name));
6740 goto out;
6741 }
6742
6743 if (ret == 0 &&
6744 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
6745 /* need to delete old one and insert a new one */
6746 ret = btrfs_del_item(trans, dev_root, path);
6747 if (ret != 0) {
6748 btrfs_warn_in_rcu(dev_root->fs_info,
6749 "delete too small dev_stats item for device %s failed %d",
6750 rcu_str_deref(device->name), ret);
6751 goto out;
6752 }
6753 ret = 1;
6754 }
6755
6756 if (ret == 1) {
6757 /* need to insert a new item */
6758 btrfs_release_path(path);
6759 ret = btrfs_insert_empty_item(trans, dev_root, path,
6760 &key, sizeof(*ptr));
6761 if (ret < 0) {
6762 btrfs_warn_in_rcu(dev_root->fs_info,
6763 "insert dev_stats item for device %s failed %d",
6764 rcu_str_deref(device->name), ret);
6765 goto out;
6766 }
6767 }
6768
6769 eb = path->nodes[0];
6770 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
6771 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6772 btrfs_set_dev_stats_value(eb, ptr, i,
6773 btrfs_dev_stat_read(device, i));
6774 btrfs_mark_buffer_dirty(eb);
6775
6776 out:
6777 btrfs_free_path(path);
6778 return ret;
6779 }
6780
6781 /*
6782 * called from commit_transaction. Writes all changed device stats to disk.
6783 */
6784 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
6785 struct btrfs_fs_info *fs_info)
6786 {
6787 struct btrfs_root *dev_root = fs_info->dev_root;
6788 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6789 struct btrfs_device *device;
6790 int stats_cnt;
6791 int ret = 0;
6792
6793 mutex_lock(&fs_devices->device_list_mutex);
6794 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6795 if (!device->dev_stats_valid || !btrfs_dev_stats_dirty(device))
6796 continue;
6797
6798 stats_cnt = atomic_read(&device->dev_stats_ccnt);
6799 ret = update_dev_stat_item(trans, dev_root, device);
6800 if (!ret)
6801 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
6802 }
6803 mutex_unlock(&fs_devices->device_list_mutex);
6804
6805 return ret;
6806 }
6807
6808 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
6809 {
6810 btrfs_dev_stat_inc(dev, index);
6811 btrfs_dev_stat_print_on_error(dev);
6812 }
6813
6814 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
6815 {
6816 if (!dev->dev_stats_valid)
6817 return;
6818 btrfs_err_rl_in_rcu(dev->dev_root->fs_info,
6819 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
6820 rcu_str_deref(dev->name),
6821 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6822 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6823 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6824 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6825 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6826 }
6827
6828 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
6829 {
6830 int i;
6831
6832 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6833 if (btrfs_dev_stat_read(dev, i) != 0)
6834 break;
6835 if (i == BTRFS_DEV_STAT_VALUES_MAX)
6836 return; /* all values == 0, suppress message */
6837
6838 btrfs_info_in_rcu(dev->dev_root->fs_info,
6839 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
6840 rcu_str_deref(dev->name),
6841 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6842 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6843 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6844 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6845 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6846 }
6847
6848 int btrfs_get_dev_stats(struct btrfs_root *root,
6849 struct btrfs_ioctl_get_dev_stats *stats)
6850 {
6851 struct btrfs_device *dev;
6852 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6853 int i;
6854
6855 mutex_lock(&fs_devices->device_list_mutex);
6856 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
6857 mutex_unlock(&fs_devices->device_list_mutex);
6858
6859 if (!dev) {
6860 btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
6861 return -ENODEV;
6862 } else if (!dev->dev_stats_valid) {
6863 btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
6864 return -ENODEV;
6865 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
6866 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6867 if (stats->nr_items > i)
6868 stats->values[i] =
6869 btrfs_dev_stat_read_and_reset(dev, i);
6870 else
6871 btrfs_dev_stat_reset(dev, i);
6872 }
6873 } else {
6874 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6875 if (stats->nr_items > i)
6876 stats->values[i] = btrfs_dev_stat_read(dev, i);
6877 }
6878 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
6879 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
6880 return 0;
6881 }
6882
6883 void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path)
6884 {
6885 struct buffer_head *bh;
6886 struct btrfs_super_block *disk_super;
6887 int copy_num;
6888
6889 if (!bdev)
6890 return;
6891
6892 for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX;
6893 copy_num++) {
6894
6895 if (btrfs_read_dev_one_super(bdev, copy_num, &bh))
6896 continue;
6897
6898 disk_super = (struct btrfs_super_block *)bh->b_data;
6899
6900 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
6901 set_buffer_dirty(bh);
6902 sync_dirty_buffer(bh);
6903 brelse(bh);
6904 }
6905
6906 /* Notify udev that device has changed */
6907 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
6908
6909 /* Update ctime/mtime for device path for libblkid */
6910 update_dev_time(device_path);
6911 }
6912
6913 /*
6914 * Update the size of all devices, which is used for writing out the
6915 * super blocks.
6916 */
6917 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info)
6918 {
6919 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6920 struct btrfs_device *curr, *next;
6921
6922 if (list_empty(&fs_devices->resized_devices))
6923 return;
6924
6925 mutex_lock(&fs_devices->device_list_mutex);
6926 lock_chunks(fs_info->dev_root);
6927 list_for_each_entry_safe(curr, next, &fs_devices->resized_devices,
6928 resized_list) {
6929 list_del_init(&curr->resized_list);
6930 curr->commit_total_bytes = curr->disk_total_bytes;
6931 }
6932 unlock_chunks(fs_info->dev_root);
6933 mutex_unlock(&fs_devices->device_list_mutex);
6934 }
6935
6936 /* Must be invoked during the transaction commit */
6937 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
6938 struct btrfs_transaction *transaction)
6939 {
6940 struct extent_map *em;
6941 struct map_lookup *map;
6942 struct btrfs_device *dev;
6943 int i;
6944
6945 if (list_empty(&transaction->pending_chunks))
6946 return;
6947
6948 /* In order to kick the device replace finish process */
6949 lock_chunks(root);
6950 list_for_each_entry(em, &transaction->pending_chunks, list) {
6951 map = (struct map_lookup *)em->bdev;
6952
6953 for (i = 0; i < map->num_stripes; i++) {
6954 dev = map->stripes[i].dev;
6955 dev->commit_bytes_used = dev->bytes_used;
6956 }
6957 }
6958 unlock_chunks(root);
6959 }
6960
6961 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info)
6962 {
6963 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6964 while (fs_devices) {
6965 fs_devices->fs_info = fs_info;
6966 fs_devices = fs_devices->seed;
6967 }
6968 }
6969
6970 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info)
6971 {
6972 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6973 while (fs_devices) {
6974 fs_devices->fs_info = NULL;
6975 fs_devices = fs_devices->seed;
6976 }
6977 }
6978
6979 void btrfs_close_one_device(struct btrfs_device *device)
6980 {
6981 struct btrfs_fs_devices *fs_devices = device->fs_devices;
6982 struct btrfs_device *new_device;
6983 struct rcu_string *name;
6984
6985 if (device->bdev)
6986 fs_devices->open_devices--;
6987
6988 if (device->writeable &&
6989 device->devid != BTRFS_DEV_REPLACE_DEVID) {
6990 list_del_init(&device->dev_alloc_list);
6991 fs_devices->rw_devices--;
6992 }
6993
6994 if (device->missing)
6995 fs_devices->missing_devices--;
6996
6997 new_device = btrfs_alloc_device(NULL, &device->devid,
6998 device->uuid);
6999 BUG_ON(IS_ERR(new_device)); /* -ENOMEM */
7000
7001 /* Safe because we are under uuid_mutex */
7002 if (device->name) {
7003 name = rcu_string_strdup(device->name->str, GFP_NOFS);
7004 BUG_ON(!name); /* -ENOMEM */
7005 rcu_assign_pointer(new_device->name, name);
7006 }
7007
7008 list_replace_rcu(&device->dev_list, &new_device->dev_list);
7009 new_device->fs_devices = device->fs_devices;
7010
7011 call_rcu(&device->rcu, free_device);
7012 }
Linux with added FPC-III support