]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - fs/btrfs/volumes.c
Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdim...
[mirror_ubuntu-bionic-kernel.git] / fs / btrfs / volumes.c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18 #include <linux/sched.h>
19 #include <linux/bio.h>
20 #include <linux/slab.h>
21 #include <linux/buffer_head.h>
22 #include <linux/blkdev.h>
23 #include <linux/iocontext.h>
24 #include <linux/capability.h>
25 #include <linux/ratelimit.h>
26 #include <linux/kthread.h>
27 #include <linux/raid/pq.h>
28 #include <linux/semaphore.h>
29 #include <linux/uuid.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 /*
122 * Table to convert BTRFS_RAID_* to the error code if minimum number of devices
123 * condition is not met. Zero means there's no corresponding
124 * BTRFS_ERROR_DEV_*_NOT_MET value.
125 */
126 const int btrfs_raid_mindev_error[BTRFS_NR_RAID_TYPES] = {
127 [BTRFS_RAID_RAID10] = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET,
128 [BTRFS_RAID_RAID1] = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET,
129 [BTRFS_RAID_DUP] = 0,
130 [BTRFS_RAID_RAID0] = 0,
131 [BTRFS_RAID_SINGLE] = 0,
132 [BTRFS_RAID_RAID5] = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET,
133 [BTRFS_RAID_RAID6] = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET,
134 };
135
136 static int init_first_rw_device(struct btrfs_trans_handle *trans,
137 struct btrfs_root *root,
138 struct btrfs_device *device);
139 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
140 static void __btrfs_reset_dev_stats(struct btrfs_device *dev);
141 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev);
142 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
143 static void btrfs_close_one_device(struct btrfs_device *device);
144
145 DEFINE_MUTEX(uuid_mutex);
146 static LIST_HEAD(fs_uuids);
147 struct list_head *btrfs_get_fs_uuids(void)
148 {
149 return &fs_uuids;
150 }
151
152 static struct btrfs_fs_devices *__alloc_fs_devices(void)
153 {
154 struct btrfs_fs_devices *fs_devs;
155
156 fs_devs = kzalloc(sizeof(*fs_devs), GFP_KERNEL);
157 if (!fs_devs)
158 return ERR_PTR(-ENOMEM);
159
160 mutex_init(&fs_devs->device_list_mutex);
161
162 INIT_LIST_HEAD(&fs_devs->devices);
163 INIT_LIST_HEAD(&fs_devs->resized_devices);
164 INIT_LIST_HEAD(&fs_devs->alloc_list);
165 INIT_LIST_HEAD(&fs_devs->list);
166
167 return fs_devs;
168 }
169
170 /**
171 * alloc_fs_devices - allocate struct btrfs_fs_devices
172 * @fsid: a pointer to UUID for this FS. If NULL a new UUID is
173 * generated.
174 *
175 * Return: a pointer to a new &struct btrfs_fs_devices on success;
176 * ERR_PTR() on error. Returned struct is not linked onto any lists and
177 * can be destroyed with kfree() right away.
178 */
179 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
180 {
181 struct btrfs_fs_devices *fs_devs;
182
183 fs_devs = __alloc_fs_devices();
184 if (IS_ERR(fs_devs))
185 return fs_devs;
186
187 if (fsid)
188 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
189 else
190 generate_random_uuid(fs_devs->fsid);
191
192 return fs_devs;
193 }
194
195 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
196 {
197 struct btrfs_device *device;
198 WARN_ON(fs_devices->opened);
199 while (!list_empty(&fs_devices->devices)) {
200 device = list_entry(fs_devices->devices.next,
201 struct btrfs_device, dev_list);
202 list_del(&device->dev_list);
203 rcu_string_free(device->name);
204 kfree(device);
205 }
206 kfree(fs_devices);
207 }
208
209 static void btrfs_kobject_uevent(struct block_device *bdev,
210 enum kobject_action action)
211 {
212 int ret;
213
214 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
215 if (ret)
216 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
217 action,
218 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
219 &disk_to_dev(bdev->bd_disk)->kobj);
220 }
221
222 void btrfs_cleanup_fs_uuids(void)
223 {
224 struct btrfs_fs_devices *fs_devices;
225
226 while (!list_empty(&fs_uuids)) {
227 fs_devices = list_entry(fs_uuids.next,
228 struct btrfs_fs_devices, list);
229 list_del(&fs_devices->list);
230 free_fs_devices(fs_devices);
231 }
232 }
233
234 static struct btrfs_device *__alloc_device(void)
235 {
236 struct btrfs_device *dev;
237
238 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
239 if (!dev)
240 return ERR_PTR(-ENOMEM);
241
242 INIT_LIST_HEAD(&dev->dev_list);
243 INIT_LIST_HEAD(&dev->dev_alloc_list);
244 INIT_LIST_HEAD(&dev->resized_list);
245
246 spin_lock_init(&dev->io_lock);
247
248 spin_lock_init(&dev->reada_lock);
249 atomic_set(&dev->reada_in_flight, 0);
250 atomic_set(&dev->dev_stats_ccnt, 0);
251 btrfs_device_data_ordered_init(dev);
252 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
253 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_DIRECT_RECLAIM);
254
255 return dev;
256 }
257
258 static noinline struct btrfs_device *__find_device(struct list_head *head,
259 u64 devid, u8 *uuid)
260 {
261 struct btrfs_device *dev;
262
263 list_for_each_entry(dev, head, dev_list) {
264 if (dev->devid == devid &&
265 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
266 return dev;
267 }
268 }
269 return NULL;
270 }
271
272 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
273 {
274 struct btrfs_fs_devices *fs_devices;
275
276 list_for_each_entry(fs_devices, &fs_uuids, list) {
277 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
278 return fs_devices;
279 }
280 return NULL;
281 }
282
283 static int
284 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
285 int flush, struct block_device **bdev,
286 struct buffer_head **bh)
287 {
288 int ret;
289
290 *bdev = blkdev_get_by_path(device_path, flags, holder);
291
292 if (IS_ERR(*bdev)) {
293 ret = PTR_ERR(*bdev);
294 goto error;
295 }
296
297 if (flush)
298 filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
299 ret = set_blocksize(*bdev, 4096);
300 if (ret) {
301 blkdev_put(*bdev, flags);
302 goto error;
303 }
304 invalidate_bdev(*bdev);
305 *bh = btrfs_read_dev_super(*bdev);
306 if (IS_ERR(*bh)) {
307 ret = PTR_ERR(*bh);
308 blkdev_put(*bdev, flags);
309 goto error;
310 }
311
312 return 0;
313
314 error:
315 *bdev = NULL;
316 *bh = NULL;
317 return ret;
318 }
319
320 static void requeue_list(struct btrfs_pending_bios *pending_bios,
321 struct bio *head, struct bio *tail)
322 {
323
324 struct bio *old_head;
325
326 old_head = pending_bios->head;
327 pending_bios->head = head;
328 if (pending_bios->tail)
329 tail->bi_next = old_head;
330 else
331 pending_bios->tail = tail;
332 }
333
334 /*
335 * we try to collect pending bios for a device so we don't get a large
336 * number of procs sending bios down to the same device. This greatly
337 * improves the schedulers ability to collect and merge the bios.
338 *
339 * But, it also turns into a long list of bios to process and that is sure
340 * to eventually make the worker thread block. The solution here is to
341 * make some progress and then put this work struct back at the end of
342 * the list if the block device is congested. This way, multiple devices
343 * can make progress from a single worker thread.
344 */
345 static noinline void run_scheduled_bios(struct btrfs_device *device)
346 {
347 struct bio *pending;
348 struct backing_dev_info *bdi;
349 struct btrfs_fs_info *fs_info;
350 struct btrfs_pending_bios *pending_bios;
351 struct bio *tail;
352 struct bio *cur;
353 int again = 0;
354 unsigned long num_run;
355 unsigned long batch_run = 0;
356 unsigned long limit;
357 unsigned long last_waited = 0;
358 int force_reg = 0;
359 int sync_pending = 0;
360 struct blk_plug plug;
361
362 /*
363 * this function runs all the bios we've collected for
364 * a particular device. We don't want to wander off to
365 * another device without first sending all of these down.
366 * So, setup a plug here and finish it off before we return
367 */
368 blk_start_plug(&plug);
369
370 bdi = blk_get_backing_dev_info(device->bdev);
371 fs_info = device->dev_root->fs_info;
372 limit = btrfs_async_submit_limit(fs_info);
373 limit = limit * 2 / 3;
374
375 loop:
376 spin_lock(&device->io_lock);
377
378 loop_lock:
379 num_run = 0;
380
381 /* take all the bios off the list at once and process them
382 * later on (without the lock held). But, remember the
383 * tail and other pointers so the bios can be properly reinserted
384 * into the list if we hit congestion
385 */
386 if (!force_reg && device->pending_sync_bios.head) {
387 pending_bios = &device->pending_sync_bios;
388 force_reg = 1;
389 } else {
390 pending_bios = &device->pending_bios;
391 force_reg = 0;
392 }
393
394 pending = pending_bios->head;
395 tail = pending_bios->tail;
396 WARN_ON(pending && !tail);
397
398 /*
399 * if pending was null this time around, no bios need processing
400 * at all and we can stop. Otherwise it'll loop back up again
401 * and do an additional check so no bios are missed.
402 *
403 * device->running_pending is used to synchronize with the
404 * schedule_bio code.
405 */
406 if (device->pending_sync_bios.head == NULL &&
407 device->pending_bios.head == NULL) {
408 again = 0;
409 device->running_pending = 0;
410 } else {
411 again = 1;
412 device->running_pending = 1;
413 }
414
415 pending_bios->head = NULL;
416 pending_bios->tail = NULL;
417
418 spin_unlock(&device->io_lock);
419
420 while (pending) {
421
422 rmb();
423 /* we want to work on both lists, but do more bios on the
424 * sync list than the regular list
425 */
426 if ((num_run > 32 &&
427 pending_bios != &device->pending_sync_bios &&
428 device->pending_sync_bios.head) ||
429 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
430 device->pending_bios.head)) {
431 spin_lock(&device->io_lock);
432 requeue_list(pending_bios, pending, tail);
433 goto loop_lock;
434 }
435
436 cur = pending;
437 pending = pending->bi_next;
438 cur->bi_next = NULL;
439
440 /*
441 * atomic_dec_return implies a barrier for waitqueue_active
442 */
443 if (atomic_dec_return(&fs_info->nr_async_bios) < limit &&
444 waitqueue_active(&fs_info->async_submit_wait))
445 wake_up(&fs_info->async_submit_wait);
446
447 BUG_ON(atomic_read(&cur->__bi_cnt) == 0);
448
449 /*
450 * if we're doing the sync list, record that our
451 * plug has some sync requests on it
452 *
453 * If we're doing the regular list and there are
454 * sync requests sitting around, unplug before
455 * we add more
456 */
457 if (pending_bios == &device->pending_sync_bios) {
458 sync_pending = 1;
459 } else if (sync_pending) {
460 blk_finish_plug(&plug);
461 blk_start_plug(&plug);
462 sync_pending = 0;
463 }
464
465 btrfsic_submit_bio(cur->bi_rw, cur);
466 num_run++;
467 batch_run++;
468
469 cond_resched();
470
471 /*
472 * we made progress, there is more work to do and the bdi
473 * is now congested. Back off and let other work structs
474 * run instead
475 */
476 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
477 fs_info->fs_devices->open_devices > 1) {
478 struct io_context *ioc;
479
480 ioc = current->io_context;
481
482 /*
483 * the main goal here is that we don't want to
484 * block if we're going to be able to submit
485 * more requests without blocking.
486 *
487 * This code does two great things, it pokes into
488 * the elevator code from a filesystem _and_
489 * it makes assumptions about how batching works.
490 */
491 if (ioc && ioc->nr_batch_requests > 0 &&
492 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
493 (last_waited == 0 ||
494 ioc->last_waited == last_waited)) {
495 /*
496 * we want to go through our batch of
497 * requests and stop. So, we copy out
498 * the ioc->last_waited time and test
499 * against it before looping
500 */
501 last_waited = ioc->last_waited;
502 cond_resched();
503 continue;
504 }
505 spin_lock(&device->io_lock);
506 requeue_list(pending_bios, pending, tail);
507 device->running_pending = 1;
508
509 spin_unlock(&device->io_lock);
510 btrfs_queue_work(fs_info->submit_workers,
511 &device->work);
512 goto done;
513 }
514 /* unplug every 64 requests just for good measure */
515 if (batch_run % 64 == 0) {
516 blk_finish_plug(&plug);
517 blk_start_plug(&plug);
518 sync_pending = 0;
519 }
520 }
521
522 cond_resched();
523 if (again)
524 goto loop;
525
526 spin_lock(&device->io_lock);
527 if (device->pending_bios.head || device->pending_sync_bios.head)
528 goto loop_lock;
529 spin_unlock(&device->io_lock);
530
531 done:
532 blk_finish_plug(&plug);
533 }
534
535 static void pending_bios_fn(struct btrfs_work *work)
536 {
537 struct btrfs_device *device;
538
539 device = container_of(work, struct btrfs_device, work);
540 run_scheduled_bios(device);
541 }
542
543
544 void btrfs_free_stale_device(struct btrfs_device *cur_dev)
545 {
546 struct btrfs_fs_devices *fs_devs;
547 struct btrfs_device *dev;
548
549 if (!cur_dev->name)
550 return;
551
552 list_for_each_entry(fs_devs, &fs_uuids, list) {
553 int del = 1;
554
555 if (fs_devs->opened)
556 continue;
557 if (fs_devs->seeding)
558 continue;
559
560 list_for_each_entry(dev, &fs_devs->devices, dev_list) {
561
562 if (dev == cur_dev)
563 continue;
564 if (!dev->name)
565 continue;
566
567 /*
568 * Todo: This won't be enough. What if the same device
569 * comes back (with new uuid and) with its mapper path?
570 * But for now, this does help as mostly an admin will
571 * either use mapper or non mapper path throughout.
572 */
573 rcu_read_lock();
574 del = strcmp(rcu_str_deref(dev->name),
575 rcu_str_deref(cur_dev->name));
576 rcu_read_unlock();
577 if (!del)
578 break;
579 }
580
581 if (!del) {
582 /* delete the stale device */
583 if (fs_devs->num_devices == 1) {
584 btrfs_sysfs_remove_fsid(fs_devs);
585 list_del(&fs_devs->list);
586 free_fs_devices(fs_devs);
587 } else {
588 fs_devs->num_devices--;
589 list_del(&dev->dev_list);
590 rcu_string_free(dev->name);
591 kfree(dev);
592 }
593 break;
594 }
595 }
596 }
597
598 /*
599 * Add new device to list of registered devices
600 *
601 * Returns:
602 * 1 - first time device is seen
603 * 0 - device already known
604 * < 0 - error
605 */
606 static noinline int device_list_add(const char *path,
607 struct btrfs_super_block *disk_super,
608 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
609 {
610 struct btrfs_device *device;
611 struct btrfs_fs_devices *fs_devices;
612 struct rcu_string *name;
613 int ret = 0;
614 u64 found_transid = btrfs_super_generation(disk_super);
615
616 fs_devices = find_fsid(disk_super->fsid);
617 if (!fs_devices) {
618 fs_devices = alloc_fs_devices(disk_super->fsid);
619 if (IS_ERR(fs_devices))
620 return PTR_ERR(fs_devices);
621
622 list_add(&fs_devices->list, &fs_uuids);
623
624 device = NULL;
625 } else {
626 device = __find_device(&fs_devices->devices, devid,
627 disk_super->dev_item.uuid);
628 }
629
630 if (!device) {
631 if (fs_devices->opened)
632 return -EBUSY;
633
634 device = btrfs_alloc_device(NULL, &devid,
635 disk_super->dev_item.uuid);
636 if (IS_ERR(device)) {
637 /* we can safely leave the fs_devices entry around */
638 return PTR_ERR(device);
639 }
640
641 name = rcu_string_strdup(path, GFP_NOFS);
642 if (!name) {
643 kfree(device);
644 return -ENOMEM;
645 }
646 rcu_assign_pointer(device->name, name);
647
648 mutex_lock(&fs_devices->device_list_mutex);
649 list_add_rcu(&device->dev_list, &fs_devices->devices);
650 fs_devices->num_devices++;
651 mutex_unlock(&fs_devices->device_list_mutex);
652
653 ret = 1;
654 device->fs_devices = fs_devices;
655 } else if (!device->name || strcmp(device->name->str, path)) {
656 /*
657 * When FS is already mounted.
658 * 1. If you are here and if the device->name is NULL that
659 * means this device was missing at time of FS mount.
660 * 2. If you are here and if the device->name is different
661 * from 'path' that means either
662 * a. The same device disappeared and reappeared with
663 * different name. or
664 * b. The missing-disk-which-was-replaced, has
665 * reappeared now.
666 *
667 * We must allow 1 and 2a above. But 2b would be a spurious
668 * and unintentional.
669 *
670 * Further in case of 1 and 2a above, the disk at 'path'
671 * would have missed some transaction when it was away and
672 * in case of 2a the stale bdev has to be updated as well.
673 * 2b must not be allowed at all time.
674 */
675
676 /*
677 * For now, we do allow update to btrfs_fs_device through the
678 * btrfs dev scan cli after FS has been mounted. We're still
679 * tracking a problem where systems fail mount by subvolume id
680 * when we reject replacement on a mounted FS.
681 */
682 if (!fs_devices->opened && found_transid < device->generation) {
683 /*
684 * That is if the FS is _not_ mounted and if you
685 * are here, that means there is more than one
686 * disk with same uuid and devid.We keep the one
687 * with larger generation number or the last-in if
688 * generation are equal.
689 */
690 return -EEXIST;
691 }
692
693 name = rcu_string_strdup(path, GFP_NOFS);
694 if (!name)
695 return -ENOMEM;
696 rcu_string_free(device->name);
697 rcu_assign_pointer(device->name, name);
698 if (device->missing) {
699 fs_devices->missing_devices--;
700 device->missing = 0;
701 }
702 }
703
704 /*
705 * Unmount does not free the btrfs_device struct but would zero
706 * generation along with most of the other members. So just update
707 * it back. We need it to pick the disk with largest generation
708 * (as above).
709 */
710 if (!fs_devices->opened)
711 device->generation = found_transid;
712
713 /*
714 * if there is new btrfs on an already registered device,
715 * then remove the stale device entry.
716 */
717 if (ret > 0)
718 btrfs_free_stale_device(device);
719
720 *fs_devices_ret = fs_devices;
721
722 return ret;
723 }
724
725 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
726 {
727 struct btrfs_fs_devices *fs_devices;
728 struct btrfs_device *device;
729 struct btrfs_device *orig_dev;
730
731 fs_devices = alloc_fs_devices(orig->fsid);
732 if (IS_ERR(fs_devices))
733 return fs_devices;
734
735 mutex_lock(&orig->device_list_mutex);
736 fs_devices->total_devices = orig->total_devices;
737
738 /* We have held the volume lock, it is safe to get the devices. */
739 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
740 struct rcu_string *name;
741
742 device = btrfs_alloc_device(NULL, &orig_dev->devid,
743 orig_dev->uuid);
744 if (IS_ERR(device))
745 goto error;
746
747 /*
748 * This is ok to do without rcu read locked because we hold the
749 * uuid mutex so nothing we touch in here is going to disappear.
750 */
751 if (orig_dev->name) {
752 name = rcu_string_strdup(orig_dev->name->str,
753 GFP_KERNEL);
754 if (!name) {
755 kfree(device);
756 goto error;
757 }
758 rcu_assign_pointer(device->name, name);
759 }
760
761 list_add(&device->dev_list, &fs_devices->devices);
762 device->fs_devices = fs_devices;
763 fs_devices->num_devices++;
764 }
765 mutex_unlock(&orig->device_list_mutex);
766 return fs_devices;
767 error:
768 mutex_unlock(&orig->device_list_mutex);
769 free_fs_devices(fs_devices);
770 return ERR_PTR(-ENOMEM);
771 }
772
773 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step)
774 {
775 struct btrfs_device *device, *next;
776 struct btrfs_device *latest_dev = NULL;
777
778 mutex_lock(&uuid_mutex);
779 again:
780 /* This is the initialized path, it is safe to release the devices. */
781 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
782 if (device->in_fs_metadata) {
783 if (!device->is_tgtdev_for_dev_replace &&
784 (!latest_dev ||
785 device->generation > latest_dev->generation)) {
786 latest_dev = device;
787 }
788 continue;
789 }
790
791 if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
792 /*
793 * In the first step, keep the device which has
794 * the correct fsid and the devid that is used
795 * for the dev_replace procedure.
796 * In the second step, the dev_replace state is
797 * read from the device tree and it is known
798 * whether the procedure is really active or
799 * not, which means whether this device is
800 * used or whether it should be removed.
801 */
802 if (step == 0 || device->is_tgtdev_for_dev_replace) {
803 continue;
804 }
805 }
806 if (device->bdev) {
807 blkdev_put(device->bdev, device->mode);
808 device->bdev = NULL;
809 fs_devices->open_devices--;
810 }
811 if (device->writeable) {
812 list_del_init(&device->dev_alloc_list);
813 device->writeable = 0;
814 if (!device->is_tgtdev_for_dev_replace)
815 fs_devices->rw_devices--;
816 }
817 list_del_init(&device->dev_list);
818 fs_devices->num_devices--;
819 rcu_string_free(device->name);
820 kfree(device);
821 }
822
823 if (fs_devices->seed) {
824 fs_devices = fs_devices->seed;
825 goto again;
826 }
827
828 fs_devices->latest_bdev = latest_dev->bdev;
829
830 mutex_unlock(&uuid_mutex);
831 }
832
833 static void __free_device(struct work_struct *work)
834 {
835 struct btrfs_device *device;
836
837 device = container_of(work, struct btrfs_device, rcu_work);
838
839 if (device->bdev)
840 blkdev_put(device->bdev, device->mode);
841
842 rcu_string_free(device->name);
843 kfree(device);
844 }
845
846 static void free_device(struct rcu_head *head)
847 {
848 struct btrfs_device *device;
849
850 device = container_of(head, struct btrfs_device, rcu);
851
852 INIT_WORK(&device->rcu_work, __free_device);
853 schedule_work(&device->rcu_work);
854 }
855
856 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
857 {
858 struct btrfs_device *device, *tmp;
859
860 if (--fs_devices->opened > 0)
861 return 0;
862
863 mutex_lock(&fs_devices->device_list_mutex);
864 list_for_each_entry_safe(device, tmp, &fs_devices->devices, dev_list) {
865 btrfs_close_one_device(device);
866 }
867 mutex_unlock(&fs_devices->device_list_mutex);
868
869 WARN_ON(fs_devices->open_devices);
870 WARN_ON(fs_devices->rw_devices);
871 fs_devices->opened = 0;
872 fs_devices->seeding = 0;
873
874 return 0;
875 }
876
877 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
878 {
879 struct btrfs_fs_devices *seed_devices = NULL;
880 int ret;
881
882 mutex_lock(&uuid_mutex);
883 ret = __btrfs_close_devices(fs_devices);
884 if (!fs_devices->opened) {
885 seed_devices = fs_devices->seed;
886 fs_devices->seed = NULL;
887 }
888 mutex_unlock(&uuid_mutex);
889
890 while (seed_devices) {
891 fs_devices = seed_devices;
892 seed_devices = fs_devices->seed;
893 __btrfs_close_devices(fs_devices);
894 free_fs_devices(fs_devices);
895 }
896 /*
897 * Wait for rcu kworkers under __btrfs_close_devices
898 * to finish all blkdev_puts so device is really
899 * free when umount is done.
900 */
901 rcu_barrier();
902 return ret;
903 }
904
905 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
906 fmode_t flags, void *holder)
907 {
908 struct request_queue *q;
909 struct block_device *bdev;
910 struct list_head *head = &fs_devices->devices;
911 struct btrfs_device *device;
912 struct btrfs_device *latest_dev = NULL;
913 struct buffer_head *bh;
914 struct btrfs_super_block *disk_super;
915 u64 devid;
916 int seeding = 1;
917 int ret = 0;
918
919 flags |= FMODE_EXCL;
920
921 list_for_each_entry(device, head, dev_list) {
922 if (device->bdev)
923 continue;
924 if (!device->name)
925 continue;
926
927 /* Just open everything we can; ignore failures here */
928 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
929 &bdev, &bh))
930 continue;
931
932 disk_super = (struct btrfs_super_block *)bh->b_data;
933 devid = btrfs_stack_device_id(&disk_super->dev_item);
934 if (devid != device->devid)
935 goto error_brelse;
936
937 if (memcmp(device->uuid, disk_super->dev_item.uuid,
938 BTRFS_UUID_SIZE))
939 goto error_brelse;
940
941 device->generation = btrfs_super_generation(disk_super);
942 if (!latest_dev ||
943 device->generation > latest_dev->generation)
944 latest_dev = device;
945
946 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
947 device->writeable = 0;
948 } else {
949 device->writeable = !bdev_read_only(bdev);
950 seeding = 0;
951 }
952
953 q = bdev_get_queue(bdev);
954 if (blk_queue_discard(q))
955 device->can_discard = 1;
956
957 device->bdev = bdev;
958 device->in_fs_metadata = 0;
959 device->mode = flags;
960
961 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
962 fs_devices->rotating = 1;
963
964 fs_devices->open_devices++;
965 if (device->writeable &&
966 device->devid != BTRFS_DEV_REPLACE_DEVID) {
967 fs_devices->rw_devices++;
968 list_add(&device->dev_alloc_list,
969 &fs_devices->alloc_list);
970 }
971 brelse(bh);
972 continue;
973
974 error_brelse:
975 brelse(bh);
976 blkdev_put(bdev, flags);
977 continue;
978 }
979 if (fs_devices->open_devices == 0) {
980 ret = -EINVAL;
981 goto out;
982 }
983 fs_devices->seeding = seeding;
984 fs_devices->opened = 1;
985 fs_devices->latest_bdev = latest_dev->bdev;
986 fs_devices->total_rw_bytes = 0;
987 out:
988 return ret;
989 }
990
991 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
992 fmode_t flags, void *holder)
993 {
994 int ret;
995
996 mutex_lock(&uuid_mutex);
997 if (fs_devices->opened) {
998 fs_devices->opened++;
999 ret = 0;
1000 } else {
1001 ret = __btrfs_open_devices(fs_devices, flags, holder);
1002 }
1003 mutex_unlock(&uuid_mutex);
1004 return ret;
1005 }
1006
1007 void btrfs_release_disk_super(struct page *page)
1008 {
1009 kunmap(page);
1010 put_page(page);
1011 }
1012
1013 int btrfs_read_disk_super(struct block_device *bdev, u64 bytenr,
1014 struct page **page, struct btrfs_super_block **disk_super)
1015 {
1016 void *p;
1017 pgoff_t index;
1018
1019 /* make sure our super fits in the device */
1020 if (bytenr + PAGE_SIZE >= i_size_read(bdev->bd_inode))
1021 return 1;
1022
1023 /* make sure our super fits in the page */
1024 if (sizeof(**disk_super) > PAGE_SIZE)
1025 return 1;
1026
1027 /* make sure our super doesn't straddle pages on disk */
1028 index = bytenr >> PAGE_SHIFT;
1029 if ((bytenr + sizeof(**disk_super) - 1) >> PAGE_SHIFT != index)
1030 return 1;
1031
1032 /* pull in the page with our super */
1033 *page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
1034 index, GFP_KERNEL);
1035
1036 if (IS_ERR_OR_NULL(*page))
1037 return 1;
1038
1039 p = kmap(*page);
1040
1041 /* align our pointer to the offset of the super block */
1042 *disk_super = p + (bytenr & ~PAGE_MASK);
1043
1044 if (btrfs_super_bytenr(*disk_super) != bytenr ||
1045 btrfs_super_magic(*disk_super) != BTRFS_MAGIC) {
1046 btrfs_release_disk_super(*page);
1047 return 1;
1048 }
1049
1050 if ((*disk_super)->label[0] &&
1051 (*disk_super)->label[BTRFS_LABEL_SIZE - 1])
1052 (*disk_super)->label[BTRFS_LABEL_SIZE - 1] = '\0';
1053
1054 return 0;
1055 }
1056
1057 /*
1058 * Look for a btrfs signature on a device. This may be called out of the mount path
1059 * and we are not allowed to call set_blocksize during the scan. The superblock
1060 * is read via pagecache
1061 */
1062 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
1063 struct btrfs_fs_devices **fs_devices_ret)
1064 {
1065 struct btrfs_super_block *disk_super;
1066 struct block_device *bdev;
1067 struct page *page;
1068 int ret = -EINVAL;
1069 u64 devid;
1070 u64 transid;
1071 u64 total_devices;
1072 u64 bytenr;
1073
1074 /*
1075 * we would like to check all the supers, but that would make
1076 * a btrfs mount succeed after a mkfs from a different FS.
1077 * So, we need to add a special mount option to scan for
1078 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
1079 */
1080 bytenr = btrfs_sb_offset(0);
1081 flags |= FMODE_EXCL;
1082 mutex_lock(&uuid_mutex);
1083
1084 bdev = blkdev_get_by_path(path, flags, holder);
1085 if (IS_ERR(bdev)) {
1086 ret = PTR_ERR(bdev);
1087 goto error;
1088 }
1089
1090 if (btrfs_read_disk_super(bdev, bytenr, &page, &disk_super))
1091 goto error_bdev_put;
1092
1093 devid = btrfs_stack_device_id(&disk_super->dev_item);
1094 transid = btrfs_super_generation(disk_super);
1095 total_devices = btrfs_super_num_devices(disk_super);
1096
1097 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
1098 if (ret > 0) {
1099 if (disk_super->label[0]) {
1100 printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
1101 } else {
1102 printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
1103 }
1104
1105 printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
1106 ret = 0;
1107 }
1108 if (!ret && fs_devices_ret)
1109 (*fs_devices_ret)->total_devices = total_devices;
1110
1111 btrfs_release_disk_super(page);
1112
1113 error_bdev_put:
1114 blkdev_put(bdev, flags);
1115 error:
1116 mutex_unlock(&uuid_mutex);
1117 return ret;
1118 }
1119
1120 /* helper to account the used device space in the range */
1121 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
1122 u64 end, u64 *length)
1123 {
1124 struct btrfs_key key;
1125 struct btrfs_root *root = device->dev_root;
1126 struct btrfs_dev_extent *dev_extent;
1127 struct btrfs_path *path;
1128 u64 extent_end;
1129 int ret;
1130 int slot;
1131 struct extent_buffer *l;
1132
1133 *length = 0;
1134
1135 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
1136 return 0;
1137
1138 path = btrfs_alloc_path();
1139 if (!path)
1140 return -ENOMEM;
1141 path->reada = READA_FORWARD;
1142
1143 key.objectid = device->devid;
1144 key.offset = start;
1145 key.type = BTRFS_DEV_EXTENT_KEY;
1146
1147 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1148 if (ret < 0)
1149 goto out;
1150 if (ret > 0) {
1151 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1152 if (ret < 0)
1153 goto out;
1154 }
1155
1156 while (1) {
1157 l = path->nodes[0];
1158 slot = path->slots[0];
1159 if (slot >= btrfs_header_nritems(l)) {
1160 ret = btrfs_next_leaf(root, path);
1161 if (ret == 0)
1162 continue;
1163 if (ret < 0)
1164 goto out;
1165
1166 break;
1167 }
1168 btrfs_item_key_to_cpu(l, &key, slot);
1169
1170 if (key.objectid < device->devid)
1171 goto next;
1172
1173 if (key.objectid > device->devid)
1174 break;
1175
1176 if (key.type != BTRFS_DEV_EXTENT_KEY)
1177 goto next;
1178
1179 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1180 extent_end = key.offset + btrfs_dev_extent_length(l,
1181 dev_extent);
1182 if (key.offset <= start && extent_end > end) {
1183 *length = end - start + 1;
1184 break;
1185 } else if (key.offset <= start && extent_end > start)
1186 *length += extent_end - start;
1187 else if (key.offset > start && extent_end <= end)
1188 *length += extent_end - key.offset;
1189 else if (key.offset > start && key.offset <= end) {
1190 *length += end - key.offset + 1;
1191 break;
1192 } else if (key.offset > end)
1193 break;
1194
1195 next:
1196 path->slots[0]++;
1197 }
1198 ret = 0;
1199 out:
1200 btrfs_free_path(path);
1201 return ret;
1202 }
1203
1204 static int contains_pending_extent(struct btrfs_transaction *transaction,
1205 struct btrfs_device *device,
1206 u64 *start, u64 len)
1207 {
1208 struct btrfs_fs_info *fs_info = device->dev_root->fs_info;
1209 struct extent_map *em;
1210 struct list_head *search_list = &fs_info->pinned_chunks;
1211 int ret = 0;
1212 u64 physical_start = *start;
1213
1214 if (transaction)
1215 search_list = &transaction->pending_chunks;
1216 again:
1217 list_for_each_entry(em, search_list, list) {
1218 struct map_lookup *map;
1219 int i;
1220
1221 map = em->map_lookup;
1222 for (i = 0; i < map->num_stripes; i++) {
1223 u64 end;
1224
1225 if (map->stripes[i].dev != device)
1226 continue;
1227 if (map->stripes[i].physical >= physical_start + len ||
1228 map->stripes[i].physical + em->orig_block_len <=
1229 physical_start)
1230 continue;
1231 /*
1232 * Make sure that while processing the pinned list we do
1233 * not override our *start with a lower value, because
1234 * we can have pinned chunks that fall within this
1235 * device hole and that have lower physical addresses
1236 * than the pending chunks we processed before. If we
1237 * do not take this special care we can end up getting
1238 * 2 pending chunks that start at the same physical
1239 * device offsets because the end offset of a pinned
1240 * chunk can be equal to the start offset of some
1241 * pending chunk.
1242 */
1243 end = map->stripes[i].physical + em->orig_block_len;
1244 if (end > *start) {
1245 *start = end;
1246 ret = 1;
1247 }
1248 }
1249 }
1250 if (search_list != &fs_info->pinned_chunks) {
1251 search_list = &fs_info->pinned_chunks;
1252 goto again;
1253 }
1254
1255 return ret;
1256 }
1257
1258
1259 /*
1260 * find_free_dev_extent_start - find free space in the specified device
1261 * @device: the device which we search the free space in
1262 * @num_bytes: the size of the free space that we need
1263 * @search_start: the position from which to begin the search
1264 * @start: store the start of the free space.
1265 * @len: the size of the free space. that we find, or the size
1266 * of the max free space if we don't find suitable free space
1267 *
1268 * this uses a pretty simple search, the expectation is that it is
1269 * called very infrequently and that a given device has a small number
1270 * of extents
1271 *
1272 * @start is used to store the start of the free space if we find. But if we
1273 * don't find suitable free space, it will be used to store the start position
1274 * of the max free space.
1275 *
1276 * @len is used to store the size of the free space that we find.
1277 * But if we don't find suitable free space, it is used to store the size of
1278 * the max free space.
1279 */
1280 int find_free_dev_extent_start(struct btrfs_transaction *transaction,
1281 struct btrfs_device *device, u64 num_bytes,
1282 u64 search_start, u64 *start, u64 *len)
1283 {
1284 struct btrfs_key key;
1285 struct btrfs_root *root = device->dev_root;
1286 struct btrfs_dev_extent *dev_extent;
1287 struct btrfs_path *path;
1288 u64 hole_size;
1289 u64 max_hole_start;
1290 u64 max_hole_size;
1291 u64 extent_end;
1292 u64 search_end = device->total_bytes;
1293 int ret;
1294 int slot;
1295 struct extent_buffer *l;
1296 u64 min_search_start;
1297
1298 /*
1299 * We don't want to overwrite the superblock on the drive nor any area
1300 * used by the boot loader (grub for example), so we make sure to start
1301 * at an offset of at least 1MB.
1302 */
1303 min_search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
1304 search_start = max(search_start, min_search_start);
1305
1306 path = btrfs_alloc_path();
1307 if (!path)
1308 return -ENOMEM;
1309
1310 max_hole_start = search_start;
1311 max_hole_size = 0;
1312
1313 again:
1314 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
1315 ret = -ENOSPC;
1316 goto out;
1317 }
1318
1319 path->reada = READA_FORWARD;
1320 path->search_commit_root = 1;
1321 path->skip_locking = 1;
1322
1323 key.objectid = device->devid;
1324 key.offset = search_start;
1325 key.type = BTRFS_DEV_EXTENT_KEY;
1326
1327 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1328 if (ret < 0)
1329 goto out;
1330 if (ret > 0) {
1331 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1332 if (ret < 0)
1333 goto out;
1334 }
1335
1336 while (1) {
1337 l = path->nodes[0];
1338 slot = path->slots[0];
1339 if (slot >= btrfs_header_nritems(l)) {
1340 ret = btrfs_next_leaf(root, path);
1341 if (ret == 0)
1342 continue;
1343 if (ret < 0)
1344 goto out;
1345
1346 break;
1347 }
1348 btrfs_item_key_to_cpu(l, &key, slot);
1349
1350 if (key.objectid < device->devid)
1351 goto next;
1352
1353 if (key.objectid > device->devid)
1354 break;
1355
1356 if (key.type != BTRFS_DEV_EXTENT_KEY)
1357 goto next;
1358
1359 if (key.offset > search_start) {
1360 hole_size = key.offset - search_start;
1361
1362 /*
1363 * Have to check before we set max_hole_start, otherwise
1364 * we could end up sending back this offset anyway.
1365 */
1366 if (contains_pending_extent(transaction, device,
1367 &search_start,
1368 hole_size)) {
1369 if (key.offset >= search_start) {
1370 hole_size = key.offset - search_start;
1371 } else {
1372 WARN_ON_ONCE(1);
1373 hole_size = 0;
1374 }
1375 }
1376
1377 if (hole_size > max_hole_size) {
1378 max_hole_start = search_start;
1379 max_hole_size = hole_size;
1380 }
1381
1382 /*
1383 * If this free space is greater than which we need,
1384 * it must be the max free space that we have found
1385 * until now, so max_hole_start must point to the start
1386 * of this free space and the length of this free space
1387 * is stored in max_hole_size. Thus, we return
1388 * max_hole_start and max_hole_size and go back to the
1389 * caller.
1390 */
1391 if (hole_size >= num_bytes) {
1392 ret = 0;
1393 goto out;
1394 }
1395 }
1396
1397 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1398 extent_end = key.offset + btrfs_dev_extent_length(l,
1399 dev_extent);
1400 if (extent_end > search_start)
1401 search_start = extent_end;
1402 next:
1403 path->slots[0]++;
1404 cond_resched();
1405 }
1406
1407 /*
1408 * At this point, search_start should be the end of
1409 * allocated dev extents, and when shrinking the device,
1410 * search_end may be smaller than search_start.
1411 */
1412 if (search_end > search_start) {
1413 hole_size = search_end - search_start;
1414
1415 if (contains_pending_extent(transaction, device, &search_start,
1416 hole_size)) {
1417 btrfs_release_path(path);
1418 goto again;
1419 }
1420
1421 if (hole_size > max_hole_size) {
1422 max_hole_start = search_start;
1423 max_hole_size = hole_size;
1424 }
1425 }
1426
1427 /* See above. */
1428 if (max_hole_size < num_bytes)
1429 ret = -ENOSPC;
1430 else
1431 ret = 0;
1432
1433 out:
1434 btrfs_free_path(path);
1435 *start = max_hole_start;
1436 if (len)
1437 *len = max_hole_size;
1438 return ret;
1439 }
1440
1441 int find_free_dev_extent(struct btrfs_trans_handle *trans,
1442 struct btrfs_device *device, u64 num_bytes,
1443 u64 *start, u64 *len)
1444 {
1445 /* FIXME use last free of some kind */
1446 return find_free_dev_extent_start(trans->transaction, device,
1447 num_bytes, 0, start, len);
1448 }
1449
1450 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1451 struct btrfs_device *device,
1452 u64 start, u64 *dev_extent_len)
1453 {
1454 int ret;
1455 struct btrfs_path *path;
1456 struct btrfs_root *root = device->dev_root;
1457 struct btrfs_key key;
1458 struct btrfs_key found_key;
1459 struct extent_buffer *leaf = NULL;
1460 struct btrfs_dev_extent *extent = NULL;
1461
1462 path = btrfs_alloc_path();
1463 if (!path)
1464 return -ENOMEM;
1465
1466 key.objectid = device->devid;
1467 key.offset = start;
1468 key.type = BTRFS_DEV_EXTENT_KEY;
1469 again:
1470 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1471 if (ret > 0) {
1472 ret = btrfs_previous_item(root, path, key.objectid,
1473 BTRFS_DEV_EXTENT_KEY);
1474 if (ret)
1475 goto out;
1476 leaf = path->nodes[0];
1477 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1478 extent = btrfs_item_ptr(leaf, path->slots[0],
1479 struct btrfs_dev_extent);
1480 BUG_ON(found_key.offset > start || found_key.offset +
1481 btrfs_dev_extent_length(leaf, extent) < start);
1482 key = found_key;
1483 btrfs_release_path(path);
1484 goto again;
1485 } else if (ret == 0) {
1486 leaf = path->nodes[0];
1487 extent = btrfs_item_ptr(leaf, path->slots[0],
1488 struct btrfs_dev_extent);
1489 } else {
1490 btrfs_handle_fs_error(root->fs_info, ret, "Slot search failed");
1491 goto out;
1492 }
1493
1494 *dev_extent_len = btrfs_dev_extent_length(leaf, extent);
1495
1496 ret = btrfs_del_item(trans, root, path);
1497 if (ret) {
1498 btrfs_handle_fs_error(root->fs_info, ret,
1499 "Failed to remove dev extent item");
1500 } else {
1501 set_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags);
1502 }
1503 out:
1504 btrfs_free_path(path);
1505 return ret;
1506 }
1507
1508 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1509 struct btrfs_device *device,
1510 u64 chunk_tree, u64 chunk_objectid,
1511 u64 chunk_offset, u64 start, u64 num_bytes)
1512 {
1513 int ret;
1514 struct btrfs_path *path;
1515 struct btrfs_root *root = device->dev_root;
1516 struct btrfs_dev_extent *extent;
1517 struct extent_buffer *leaf;
1518 struct btrfs_key key;
1519
1520 WARN_ON(!device->in_fs_metadata);
1521 WARN_ON(device->is_tgtdev_for_dev_replace);
1522 path = btrfs_alloc_path();
1523 if (!path)
1524 return -ENOMEM;
1525
1526 key.objectid = device->devid;
1527 key.offset = start;
1528 key.type = BTRFS_DEV_EXTENT_KEY;
1529 ret = btrfs_insert_empty_item(trans, root, path, &key,
1530 sizeof(*extent));
1531 if (ret)
1532 goto out;
1533
1534 leaf = path->nodes[0];
1535 extent = btrfs_item_ptr(leaf, path->slots[0],
1536 struct btrfs_dev_extent);
1537 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1538 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1539 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1540
1541 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1542 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE);
1543
1544 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1545 btrfs_mark_buffer_dirty(leaf);
1546 out:
1547 btrfs_free_path(path);
1548 return ret;
1549 }
1550
1551 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1552 {
1553 struct extent_map_tree *em_tree;
1554 struct extent_map *em;
1555 struct rb_node *n;
1556 u64 ret = 0;
1557
1558 em_tree = &fs_info->mapping_tree.map_tree;
1559 read_lock(&em_tree->lock);
1560 n = rb_last(&em_tree->map);
1561 if (n) {
1562 em = rb_entry(n, struct extent_map, rb_node);
1563 ret = em->start + em->len;
1564 }
1565 read_unlock(&em_tree->lock);
1566
1567 return ret;
1568 }
1569
1570 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1571 u64 *devid_ret)
1572 {
1573 int ret;
1574 struct btrfs_key key;
1575 struct btrfs_key found_key;
1576 struct btrfs_path *path;
1577
1578 path = btrfs_alloc_path();
1579 if (!path)
1580 return -ENOMEM;
1581
1582 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1583 key.type = BTRFS_DEV_ITEM_KEY;
1584 key.offset = (u64)-1;
1585
1586 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1587 if (ret < 0)
1588 goto error;
1589
1590 BUG_ON(ret == 0); /* Corruption */
1591
1592 ret = btrfs_previous_item(fs_info->chunk_root, path,
1593 BTRFS_DEV_ITEMS_OBJECTID,
1594 BTRFS_DEV_ITEM_KEY);
1595 if (ret) {
1596 *devid_ret = 1;
1597 } else {
1598 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1599 path->slots[0]);
1600 *devid_ret = found_key.offset + 1;
1601 }
1602 ret = 0;
1603 error:
1604 btrfs_free_path(path);
1605 return ret;
1606 }
1607
1608 /*
1609 * the device information is stored in the chunk root
1610 * the btrfs_device struct should be fully filled in
1611 */
1612 static int btrfs_add_device(struct btrfs_trans_handle *trans,
1613 struct btrfs_root *root,
1614 struct btrfs_device *device)
1615 {
1616 int ret;
1617 struct btrfs_path *path;
1618 struct btrfs_dev_item *dev_item;
1619 struct extent_buffer *leaf;
1620 struct btrfs_key key;
1621 unsigned long ptr;
1622
1623 root = root->fs_info->chunk_root;
1624
1625 path = btrfs_alloc_path();
1626 if (!path)
1627 return -ENOMEM;
1628
1629 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1630 key.type = BTRFS_DEV_ITEM_KEY;
1631 key.offset = device->devid;
1632
1633 ret = btrfs_insert_empty_item(trans, root, path, &key,
1634 sizeof(*dev_item));
1635 if (ret)
1636 goto out;
1637
1638 leaf = path->nodes[0];
1639 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1640
1641 btrfs_set_device_id(leaf, dev_item, device->devid);
1642 btrfs_set_device_generation(leaf, dev_item, 0);
1643 btrfs_set_device_type(leaf, dev_item, device->type);
1644 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1645 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1646 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1647 btrfs_set_device_total_bytes(leaf, dev_item,
1648 btrfs_device_get_disk_total_bytes(device));
1649 btrfs_set_device_bytes_used(leaf, dev_item,
1650 btrfs_device_get_bytes_used(device));
1651 btrfs_set_device_group(leaf, dev_item, 0);
1652 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1653 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1654 btrfs_set_device_start_offset(leaf, dev_item, 0);
1655
1656 ptr = btrfs_device_uuid(dev_item);
1657 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1658 ptr = btrfs_device_fsid(dev_item);
1659 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1660 btrfs_mark_buffer_dirty(leaf);
1661
1662 ret = 0;
1663 out:
1664 btrfs_free_path(path);
1665 return ret;
1666 }
1667
1668 /*
1669 * Function to update ctime/mtime for a given device path.
1670 * Mainly used for ctime/mtime based probe like libblkid.
1671 */
1672 static void update_dev_time(char *path_name)
1673 {
1674 struct file *filp;
1675
1676 filp = filp_open(path_name, O_RDWR, 0);
1677 if (IS_ERR(filp))
1678 return;
1679 file_update_time(filp);
1680 filp_close(filp, NULL);
1681 }
1682
1683 static int btrfs_rm_dev_item(struct btrfs_root *root,
1684 struct btrfs_device *device)
1685 {
1686 int ret;
1687 struct btrfs_path *path;
1688 struct btrfs_key key;
1689 struct btrfs_trans_handle *trans;
1690
1691 root = root->fs_info->chunk_root;
1692
1693 path = btrfs_alloc_path();
1694 if (!path)
1695 return -ENOMEM;
1696
1697 trans = btrfs_start_transaction(root, 0);
1698 if (IS_ERR(trans)) {
1699 btrfs_free_path(path);
1700 return PTR_ERR(trans);
1701 }
1702 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1703 key.type = BTRFS_DEV_ITEM_KEY;
1704 key.offset = device->devid;
1705
1706 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1707 if (ret < 0)
1708 goto out;
1709
1710 if (ret > 0) {
1711 ret = -ENOENT;
1712 goto out;
1713 }
1714
1715 ret = btrfs_del_item(trans, root, path);
1716 if (ret)
1717 goto out;
1718 out:
1719 btrfs_free_path(path);
1720 btrfs_commit_transaction(trans, root);
1721 return ret;
1722 }
1723
1724 /*
1725 * Verify that @num_devices satisfies the RAID profile constraints in the whole
1726 * filesystem. It's up to the caller to adjust that number regarding eg. device
1727 * replace.
1728 */
1729 static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
1730 u64 num_devices)
1731 {
1732 u64 all_avail;
1733 unsigned seq;
1734 int i;
1735
1736 do {
1737 seq = read_seqbegin(&fs_info->profiles_lock);
1738
1739 all_avail = fs_info->avail_data_alloc_bits |
1740 fs_info->avail_system_alloc_bits |
1741 fs_info->avail_metadata_alloc_bits;
1742 } while (read_seqretry(&fs_info->profiles_lock, seq));
1743
1744 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
1745 if (!(all_avail & btrfs_raid_group[i]))
1746 continue;
1747
1748 if (num_devices < btrfs_raid_array[i].devs_min) {
1749 int ret = btrfs_raid_mindev_error[i];
1750
1751 if (ret)
1752 return ret;
1753 }
1754 }
1755
1756 return 0;
1757 }
1758
1759 struct btrfs_device *btrfs_find_next_active_device(struct btrfs_fs_devices *fs_devs,
1760 struct btrfs_device *device)
1761 {
1762 struct btrfs_device *next_device;
1763
1764 list_for_each_entry(next_device, &fs_devs->devices, dev_list) {
1765 if (next_device != device &&
1766 !next_device->missing && next_device->bdev)
1767 return next_device;
1768 }
1769
1770 return NULL;
1771 }
1772
1773 /*
1774 * Helper function to check if the given device is part of s_bdev / latest_bdev
1775 * and replace it with the provided or the next active device, in the context
1776 * where this function called, there should be always be another device (or
1777 * this_dev) which is active.
1778 */
1779 void btrfs_assign_next_active_device(struct btrfs_fs_info *fs_info,
1780 struct btrfs_device *device, struct btrfs_device *this_dev)
1781 {
1782 struct btrfs_device *next_device;
1783
1784 if (this_dev)
1785 next_device = this_dev;
1786 else
1787 next_device = btrfs_find_next_active_device(fs_info->fs_devices,
1788 device);
1789 ASSERT(next_device);
1790
1791 if (fs_info->sb->s_bdev &&
1792 (fs_info->sb->s_bdev == device->bdev))
1793 fs_info->sb->s_bdev = next_device->bdev;
1794
1795 if (fs_info->fs_devices->latest_bdev == device->bdev)
1796 fs_info->fs_devices->latest_bdev = next_device->bdev;
1797 }
1798
1799 int btrfs_rm_device(struct btrfs_root *root, char *device_path, u64 devid)
1800 {
1801 struct btrfs_device *device;
1802 struct btrfs_fs_devices *cur_devices;
1803 u64 num_devices;
1804 int ret = 0;
1805 bool clear_super = false;
1806 char *dev_name = NULL;
1807
1808 mutex_lock(&uuid_mutex);
1809
1810 num_devices = root->fs_info->fs_devices->num_devices;
1811 btrfs_dev_replace_lock(&root->fs_info->dev_replace, 0);
1812 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1813 WARN_ON(num_devices < 1);
1814 num_devices--;
1815 }
1816 btrfs_dev_replace_unlock(&root->fs_info->dev_replace, 0);
1817
1818 ret = btrfs_check_raid_min_devices(root->fs_info, num_devices - 1);
1819 if (ret)
1820 goto out;
1821
1822 ret = btrfs_find_device_by_devspec(root, devid, device_path,
1823 &device);
1824 if (ret)
1825 goto out;
1826
1827 if (device->is_tgtdev_for_dev_replace) {
1828 ret = BTRFS_ERROR_DEV_TGT_REPLACE;
1829 goto out;
1830 }
1831
1832 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1833 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
1834 goto out;
1835 }
1836
1837 if (device->writeable) {
1838 lock_chunks(root);
1839 list_del_init(&device->dev_alloc_list);
1840 device->fs_devices->rw_devices--;
1841 unlock_chunks(root);
1842 dev_name = kstrdup(device->name->str, GFP_KERNEL);
1843 if (!dev_name) {
1844 ret = -ENOMEM;
1845 goto error_undo;
1846 }
1847 clear_super = true;
1848 }
1849
1850 mutex_unlock(&uuid_mutex);
1851 ret = btrfs_shrink_device(device, 0);
1852 mutex_lock(&uuid_mutex);
1853 if (ret)
1854 goto error_undo;
1855
1856 /*
1857 * TODO: the superblock still includes this device in its num_devices
1858 * counter although write_all_supers() is not locked out. This
1859 * could give a filesystem state which requires a degraded mount.
1860 */
1861 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1862 if (ret)
1863 goto error_undo;
1864
1865 device->in_fs_metadata = 0;
1866 btrfs_scrub_cancel_dev(root->fs_info, device);
1867
1868 /*
1869 * the device list mutex makes sure that we don't change
1870 * the device list while someone else is writing out all
1871 * the device supers. Whoever is writing all supers, should
1872 * lock the device list mutex before getting the number of
1873 * devices in the super block (super_copy). Conversely,
1874 * whoever updates the number of devices in the super block
1875 * (super_copy) should hold the device list mutex.
1876 */
1877
1878 cur_devices = device->fs_devices;
1879 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1880 list_del_rcu(&device->dev_list);
1881
1882 device->fs_devices->num_devices--;
1883 device->fs_devices->total_devices--;
1884
1885 if (device->missing)
1886 device->fs_devices->missing_devices--;
1887
1888 btrfs_assign_next_active_device(root->fs_info, device, NULL);
1889
1890 if (device->bdev) {
1891 device->fs_devices->open_devices--;
1892 /* remove sysfs entry */
1893 btrfs_sysfs_rm_device_link(root->fs_info->fs_devices, device);
1894 }
1895
1896 call_rcu(&device->rcu, free_device);
1897
1898 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1899 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1900 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1901
1902 if (cur_devices->open_devices == 0) {
1903 struct btrfs_fs_devices *fs_devices;
1904 fs_devices = root->fs_info->fs_devices;
1905 while (fs_devices) {
1906 if (fs_devices->seed == cur_devices) {
1907 fs_devices->seed = cur_devices->seed;
1908 break;
1909 }
1910 fs_devices = fs_devices->seed;
1911 }
1912 cur_devices->seed = NULL;
1913 __btrfs_close_devices(cur_devices);
1914 free_fs_devices(cur_devices);
1915 }
1916
1917 root->fs_info->num_tolerated_disk_barrier_failures =
1918 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1919
1920 /*
1921 * at this point, the device is zero sized. We want to
1922 * remove it from the devices list and zero out the old super
1923 */
1924 if (clear_super) {
1925 struct block_device *bdev;
1926
1927 bdev = blkdev_get_by_path(dev_name, FMODE_READ | FMODE_EXCL,
1928 root->fs_info->bdev_holder);
1929 if (!IS_ERR(bdev)) {
1930 btrfs_scratch_superblocks(bdev, dev_name);
1931 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1932 }
1933 }
1934
1935 out:
1936 kfree(dev_name);
1937
1938 mutex_unlock(&uuid_mutex);
1939 return ret;
1940
1941 error_undo:
1942 if (device->writeable) {
1943 lock_chunks(root);
1944 list_add(&device->dev_alloc_list,
1945 &root->fs_info->fs_devices->alloc_list);
1946 device->fs_devices->rw_devices++;
1947 unlock_chunks(root);
1948 }
1949 goto out;
1950 }
1951
1952 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info,
1953 struct btrfs_device *srcdev)
1954 {
1955 struct btrfs_fs_devices *fs_devices;
1956
1957 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1958
1959 /*
1960 * in case of fs with no seed, srcdev->fs_devices will point
1961 * to fs_devices of fs_info. However when the dev being replaced is
1962 * a seed dev it will point to the seed's local fs_devices. In short
1963 * srcdev will have its correct fs_devices in both the cases.
1964 */
1965 fs_devices = srcdev->fs_devices;
1966
1967 list_del_rcu(&srcdev->dev_list);
1968 list_del_rcu(&srcdev->dev_alloc_list);
1969 fs_devices->num_devices--;
1970 if (srcdev->missing)
1971 fs_devices->missing_devices--;
1972
1973 if (srcdev->writeable)
1974 fs_devices->rw_devices--;
1975
1976 if (srcdev->bdev)
1977 fs_devices->open_devices--;
1978 }
1979
1980 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info,
1981 struct btrfs_device *srcdev)
1982 {
1983 struct btrfs_fs_devices *fs_devices = srcdev->fs_devices;
1984
1985 if (srcdev->writeable) {
1986 /* zero out the old super if it is writable */
1987 btrfs_scratch_superblocks(srcdev->bdev, srcdev->name->str);
1988 }
1989 call_rcu(&srcdev->rcu, free_device);
1990
1991 /*
1992 * unless fs_devices is seed fs, num_devices shouldn't go
1993 * zero
1994 */
1995 BUG_ON(!fs_devices->num_devices && !fs_devices->seeding);
1996
1997 /* if this is no devs we rather delete the fs_devices */
1998 if (!fs_devices->num_devices) {
1999 struct btrfs_fs_devices *tmp_fs_devices;
2000
2001 tmp_fs_devices = fs_info->fs_devices;
2002 while (tmp_fs_devices) {
2003 if (tmp_fs_devices->seed == fs_devices) {
2004 tmp_fs_devices->seed = fs_devices->seed;
2005 break;
2006 }
2007 tmp_fs_devices = tmp_fs_devices->seed;
2008 }
2009 fs_devices->seed = NULL;
2010 __btrfs_close_devices(fs_devices);
2011 free_fs_devices(fs_devices);
2012 }
2013 }
2014
2015 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
2016 struct btrfs_device *tgtdev)
2017 {
2018 mutex_lock(&uuid_mutex);
2019 WARN_ON(!tgtdev);
2020 mutex_lock(&fs_info->fs_devices->device_list_mutex);
2021
2022 btrfs_sysfs_rm_device_link(fs_info->fs_devices, tgtdev);
2023
2024 if (tgtdev->bdev)
2025 fs_info->fs_devices->open_devices--;
2026
2027 fs_info->fs_devices->num_devices--;
2028
2029 btrfs_assign_next_active_device(fs_info, tgtdev, NULL);
2030
2031 list_del_rcu(&tgtdev->dev_list);
2032
2033 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2034 mutex_unlock(&uuid_mutex);
2035
2036 /*
2037 * The update_dev_time() with in btrfs_scratch_superblocks()
2038 * may lead to a call to btrfs_show_devname() which will try
2039 * to hold device_list_mutex. And here this device
2040 * is already out of device list, so we don't have to hold
2041 * the device_list_mutex lock.
2042 */
2043 btrfs_scratch_superblocks(tgtdev->bdev, tgtdev->name->str);
2044 call_rcu(&tgtdev->rcu, free_device);
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 * Lookup a device given by device id, or the path if the id is 0.
2106 */
2107 int btrfs_find_device_by_devspec(struct btrfs_root *root, u64 devid,
2108 char *devpath,
2109 struct btrfs_device **device)
2110 {
2111 int ret;
2112
2113 if (devid) {
2114 ret = 0;
2115 *device = btrfs_find_device(root->fs_info, devid, NULL,
2116 NULL);
2117 if (!*device)
2118 ret = -ENOENT;
2119 } else {
2120 if (!devpath || !devpath[0])
2121 return -EINVAL;
2122
2123 ret = btrfs_find_device_missing_or_by_path(root, devpath,
2124 device);
2125 }
2126 return ret;
2127 }
2128
2129 /*
2130 * does all the dirty work required for changing file system's UUID.
2131 */
2132 static int btrfs_prepare_sprout(struct btrfs_root *root)
2133 {
2134 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2135 struct btrfs_fs_devices *old_devices;
2136 struct btrfs_fs_devices *seed_devices;
2137 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
2138 struct btrfs_device *device;
2139 u64 super_flags;
2140
2141 BUG_ON(!mutex_is_locked(&uuid_mutex));
2142 if (!fs_devices->seeding)
2143 return -EINVAL;
2144
2145 seed_devices = __alloc_fs_devices();
2146 if (IS_ERR(seed_devices))
2147 return PTR_ERR(seed_devices);
2148
2149 old_devices = clone_fs_devices(fs_devices);
2150 if (IS_ERR(old_devices)) {
2151 kfree(seed_devices);
2152 return PTR_ERR(old_devices);
2153 }
2154
2155 list_add(&old_devices->list, &fs_uuids);
2156
2157 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
2158 seed_devices->opened = 1;
2159 INIT_LIST_HEAD(&seed_devices->devices);
2160 INIT_LIST_HEAD(&seed_devices->alloc_list);
2161 mutex_init(&seed_devices->device_list_mutex);
2162
2163 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2164 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
2165 synchronize_rcu);
2166 list_for_each_entry(device, &seed_devices->devices, dev_list)
2167 device->fs_devices = seed_devices;
2168
2169 lock_chunks(root);
2170 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
2171 unlock_chunks(root);
2172
2173 fs_devices->seeding = 0;
2174 fs_devices->num_devices = 0;
2175 fs_devices->open_devices = 0;
2176 fs_devices->missing_devices = 0;
2177 fs_devices->rotating = 0;
2178 fs_devices->seed = seed_devices;
2179
2180 generate_random_uuid(fs_devices->fsid);
2181 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2182 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
2183 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2184
2185 super_flags = btrfs_super_flags(disk_super) &
2186 ~BTRFS_SUPER_FLAG_SEEDING;
2187 btrfs_set_super_flags(disk_super, super_flags);
2188
2189 return 0;
2190 }
2191
2192 /*
2193 * Store the expected generation for seed devices in device items.
2194 */
2195 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
2196 struct btrfs_root *root)
2197 {
2198 struct btrfs_path *path;
2199 struct extent_buffer *leaf;
2200 struct btrfs_dev_item *dev_item;
2201 struct btrfs_device *device;
2202 struct btrfs_key key;
2203 u8 fs_uuid[BTRFS_UUID_SIZE];
2204 u8 dev_uuid[BTRFS_UUID_SIZE];
2205 u64 devid;
2206 int ret;
2207
2208 path = btrfs_alloc_path();
2209 if (!path)
2210 return -ENOMEM;
2211
2212 root = root->fs_info->chunk_root;
2213 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2214 key.offset = 0;
2215 key.type = BTRFS_DEV_ITEM_KEY;
2216
2217 while (1) {
2218 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2219 if (ret < 0)
2220 goto error;
2221
2222 leaf = path->nodes[0];
2223 next_slot:
2224 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
2225 ret = btrfs_next_leaf(root, path);
2226 if (ret > 0)
2227 break;
2228 if (ret < 0)
2229 goto error;
2230 leaf = path->nodes[0];
2231 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2232 btrfs_release_path(path);
2233 continue;
2234 }
2235
2236 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2237 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2238 key.type != BTRFS_DEV_ITEM_KEY)
2239 break;
2240
2241 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2242 struct btrfs_dev_item);
2243 devid = btrfs_device_id(leaf, dev_item);
2244 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2245 BTRFS_UUID_SIZE);
2246 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2247 BTRFS_UUID_SIZE);
2248 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2249 fs_uuid);
2250 BUG_ON(!device); /* Logic error */
2251
2252 if (device->fs_devices->seeding) {
2253 btrfs_set_device_generation(leaf, dev_item,
2254 device->generation);
2255 btrfs_mark_buffer_dirty(leaf);
2256 }
2257
2258 path->slots[0]++;
2259 goto next_slot;
2260 }
2261 ret = 0;
2262 error:
2263 btrfs_free_path(path);
2264 return ret;
2265 }
2266
2267 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
2268 {
2269 struct request_queue *q;
2270 struct btrfs_trans_handle *trans;
2271 struct btrfs_device *device;
2272 struct block_device *bdev;
2273 struct list_head *devices;
2274 struct super_block *sb = root->fs_info->sb;
2275 struct rcu_string *name;
2276 u64 tmp;
2277 int seeding_dev = 0;
2278 int ret = 0;
2279
2280 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
2281 return -EROFS;
2282
2283 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2284 root->fs_info->bdev_holder);
2285 if (IS_ERR(bdev))
2286 return PTR_ERR(bdev);
2287
2288 if (root->fs_info->fs_devices->seeding) {
2289 seeding_dev = 1;
2290 down_write(&sb->s_umount);
2291 mutex_lock(&uuid_mutex);
2292 }
2293
2294 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2295
2296 devices = &root->fs_info->fs_devices->devices;
2297
2298 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2299 list_for_each_entry(device, devices, dev_list) {
2300 if (device->bdev == bdev) {
2301 ret = -EEXIST;
2302 mutex_unlock(
2303 &root->fs_info->fs_devices->device_list_mutex);
2304 goto error;
2305 }
2306 }
2307 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2308
2309 device = btrfs_alloc_device(root->fs_info, NULL, NULL);
2310 if (IS_ERR(device)) {
2311 /* we can safely leave the fs_devices entry around */
2312 ret = PTR_ERR(device);
2313 goto error;
2314 }
2315
2316 name = rcu_string_strdup(device_path, GFP_KERNEL);
2317 if (!name) {
2318 kfree(device);
2319 ret = -ENOMEM;
2320 goto error;
2321 }
2322 rcu_assign_pointer(device->name, name);
2323
2324 trans = btrfs_start_transaction(root, 0);
2325 if (IS_ERR(trans)) {
2326 rcu_string_free(device->name);
2327 kfree(device);
2328 ret = PTR_ERR(trans);
2329 goto error;
2330 }
2331
2332 q = bdev_get_queue(bdev);
2333 if (blk_queue_discard(q))
2334 device->can_discard = 1;
2335 device->writeable = 1;
2336 device->generation = trans->transid;
2337 device->io_width = root->sectorsize;
2338 device->io_align = root->sectorsize;
2339 device->sector_size = root->sectorsize;
2340 device->total_bytes = i_size_read(bdev->bd_inode);
2341 device->disk_total_bytes = device->total_bytes;
2342 device->commit_total_bytes = device->total_bytes;
2343 device->dev_root = root->fs_info->dev_root;
2344 device->bdev = bdev;
2345 device->in_fs_metadata = 1;
2346 device->is_tgtdev_for_dev_replace = 0;
2347 device->mode = FMODE_EXCL;
2348 device->dev_stats_valid = 1;
2349 set_blocksize(device->bdev, 4096);
2350
2351 if (seeding_dev) {
2352 sb->s_flags &= ~MS_RDONLY;
2353 ret = btrfs_prepare_sprout(root);
2354 BUG_ON(ret); /* -ENOMEM */
2355 }
2356
2357 device->fs_devices = root->fs_info->fs_devices;
2358
2359 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2360 lock_chunks(root);
2361 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
2362 list_add(&device->dev_alloc_list,
2363 &root->fs_info->fs_devices->alloc_list);
2364 root->fs_info->fs_devices->num_devices++;
2365 root->fs_info->fs_devices->open_devices++;
2366 root->fs_info->fs_devices->rw_devices++;
2367 root->fs_info->fs_devices->total_devices++;
2368 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
2369
2370 spin_lock(&root->fs_info->free_chunk_lock);
2371 root->fs_info->free_chunk_space += device->total_bytes;
2372 spin_unlock(&root->fs_info->free_chunk_lock);
2373
2374 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
2375 root->fs_info->fs_devices->rotating = 1;
2376
2377 tmp = btrfs_super_total_bytes(root->fs_info->super_copy);
2378 btrfs_set_super_total_bytes(root->fs_info->super_copy,
2379 tmp + device->total_bytes);
2380
2381 tmp = btrfs_super_num_devices(root->fs_info->super_copy);
2382 btrfs_set_super_num_devices(root->fs_info->super_copy,
2383 tmp + 1);
2384
2385 /* add sysfs device entry */
2386 btrfs_sysfs_add_device_link(root->fs_info->fs_devices, device);
2387
2388 /*
2389 * we've got more storage, clear any full flags on the space
2390 * infos
2391 */
2392 btrfs_clear_space_info_full(root->fs_info);
2393
2394 unlock_chunks(root);
2395 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2396
2397 if (seeding_dev) {
2398 lock_chunks(root);
2399 ret = init_first_rw_device(trans, root, device);
2400 unlock_chunks(root);
2401 if (ret) {
2402 btrfs_abort_transaction(trans, root, ret);
2403 goto error_trans;
2404 }
2405 }
2406
2407 ret = btrfs_add_device(trans, root, device);
2408 if (ret) {
2409 btrfs_abort_transaction(trans, root, ret);
2410 goto error_trans;
2411 }
2412
2413 if (seeding_dev) {
2414 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2415
2416 ret = btrfs_finish_sprout(trans, root);
2417 if (ret) {
2418 btrfs_abort_transaction(trans, root, ret);
2419 goto error_trans;
2420 }
2421
2422 /* Sprouting would change fsid of the mounted root,
2423 * so rename the fsid on the sysfs
2424 */
2425 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU",
2426 root->fs_info->fsid);
2427 if (kobject_rename(&root->fs_info->fs_devices->fsid_kobj,
2428 fsid_buf))
2429 btrfs_warn(root->fs_info,
2430 "sysfs: failed to create fsid for sprout");
2431 }
2432
2433 root->fs_info->num_tolerated_disk_barrier_failures =
2434 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2435 ret = btrfs_commit_transaction(trans, root);
2436
2437 if (seeding_dev) {
2438 mutex_unlock(&uuid_mutex);
2439 up_write(&sb->s_umount);
2440
2441 if (ret) /* transaction commit */
2442 return ret;
2443
2444 ret = btrfs_relocate_sys_chunks(root);
2445 if (ret < 0)
2446 btrfs_handle_fs_error(root->fs_info, ret,
2447 "Failed to relocate sys chunks after "
2448 "device initialization. This can be fixed "
2449 "using the \"btrfs balance\" command.");
2450 trans = btrfs_attach_transaction(root);
2451 if (IS_ERR(trans)) {
2452 if (PTR_ERR(trans) == -ENOENT)
2453 return 0;
2454 return PTR_ERR(trans);
2455 }
2456 ret = btrfs_commit_transaction(trans, root);
2457 }
2458
2459 /* Update ctime/mtime for libblkid */
2460 update_dev_time(device_path);
2461 return ret;
2462
2463 error_trans:
2464 btrfs_end_transaction(trans, root);
2465 rcu_string_free(device->name);
2466 btrfs_sysfs_rm_device_link(root->fs_info->fs_devices, device);
2467 kfree(device);
2468 error:
2469 blkdev_put(bdev, FMODE_EXCL);
2470 if (seeding_dev) {
2471 mutex_unlock(&uuid_mutex);
2472 up_write(&sb->s_umount);
2473 }
2474 return ret;
2475 }
2476
2477 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2478 struct btrfs_device *srcdev,
2479 struct btrfs_device **device_out)
2480 {
2481 struct request_queue *q;
2482 struct btrfs_device *device;
2483 struct block_device *bdev;
2484 struct btrfs_fs_info *fs_info = root->fs_info;
2485 struct list_head *devices;
2486 struct rcu_string *name;
2487 u64 devid = BTRFS_DEV_REPLACE_DEVID;
2488 int ret = 0;
2489
2490 *device_out = NULL;
2491 if (fs_info->fs_devices->seeding) {
2492 btrfs_err(fs_info, "the filesystem is a seed filesystem!");
2493 return -EINVAL;
2494 }
2495
2496 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2497 fs_info->bdev_holder);
2498 if (IS_ERR(bdev)) {
2499 btrfs_err(fs_info, "target device %s is invalid!", device_path);
2500 return PTR_ERR(bdev);
2501 }
2502
2503 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2504
2505 devices = &fs_info->fs_devices->devices;
2506 list_for_each_entry(device, devices, dev_list) {
2507 if (device->bdev == bdev) {
2508 btrfs_err(fs_info, "target device is in the filesystem!");
2509 ret = -EEXIST;
2510 goto error;
2511 }
2512 }
2513
2514
2515 if (i_size_read(bdev->bd_inode) <
2516 btrfs_device_get_total_bytes(srcdev)) {
2517 btrfs_err(fs_info, "target device is smaller than source device!");
2518 ret = -EINVAL;
2519 goto error;
2520 }
2521
2522
2523 device = btrfs_alloc_device(NULL, &devid, NULL);
2524 if (IS_ERR(device)) {
2525 ret = PTR_ERR(device);
2526 goto error;
2527 }
2528
2529 name = rcu_string_strdup(device_path, GFP_NOFS);
2530 if (!name) {
2531 kfree(device);
2532 ret = -ENOMEM;
2533 goto error;
2534 }
2535 rcu_assign_pointer(device->name, name);
2536
2537 q = bdev_get_queue(bdev);
2538 if (blk_queue_discard(q))
2539 device->can_discard = 1;
2540 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2541 device->writeable = 1;
2542 device->generation = 0;
2543 device->io_width = root->sectorsize;
2544 device->io_align = root->sectorsize;
2545 device->sector_size = root->sectorsize;
2546 device->total_bytes = btrfs_device_get_total_bytes(srcdev);
2547 device->disk_total_bytes = btrfs_device_get_disk_total_bytes(srcdev);
2548 device->bytes_used = btrfs_device_get_bytes_used(srcdev);
2549 ASSERT(list_empty(&srcdev->resized_list));
2550 device->commit_total_bytes = srcdev->commit_total_bytes;
2551 device->commit_bytes_used = device->bytes_used;
2552 device->dev_root = fs_info->dev_root;
2553 device->bdev = bdev;
2554 device->in_fs_metadata = 1;
2555 device->is_tgtdev_for_dev_replace = 1;
2556 device->mode = FMODE_EXCL;
2557 device->dev_stats_valid = 1;
2558 set_blocksize(device->bdev, 4096);
2559 device->fs_devices = fs_info->fs_devices;
2560 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2561 fs_info->fs_devices->num_devices++;
2562 fs_info->fs_devices->open_devices++;
2563 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2564
2565 *device_out = device;
2566 return ret;
2567
2568 error:
2569 blkdev_put(bdev, FMODE_EXCL);
2570 return ret;
2571 }
2572
2573 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2574 struct btrfs_device *tgtdev)
2575 {
2576 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2577 tgtdev->io_width = fs_info->dev_root->sectorsize;
2578 tgtdev->io_align = fs_info->dev_root->sectorsize;
2579 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2580 tgtdev->dev_root = fs_info->dev_root;
2581 tgtdev->in_fs_metadata = 1;
2582 }
2583
2584 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2585 struct btrfs_device *device)
2586 {
2587 int ret;
2588 struct btrfs_path *path;
2589 struct btrfs_root *root;
2590 struct btrfs_dev_item *dev_item;
2591 struct extent_buffer *leaf;
2592 struct btrfs_key key;
2593
2594 root = device->dev_root->fs_info->chunk_root;
2595
2596 path = btrfs_alloc_path();
2597 if (!path)
2598 return -ENOMEM;
2599
2600 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2601 key.type = BTRFS_DEV_ITEM_KEY;
2602 key.offset = device->devid;
2603
2604 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2605 if (ret < 0)
2606 goto out;
2607
2608 if (ret > 0) {
2609 ret = -ENOENT;
2610 goto out;
2611 }
2612
2613 leaf = path->nodes[0];
2614 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2615
2616 btrfs_set_device_id(leaf, dev_item, device->devid);
2617 btrfs_set_device_type(leaf, dev_item, device->type);
2618 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2619 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2620 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2621 btrfs_set_device_total_bytes(leaf, dev_item,
2622 btrfs_device_get_disk_total_bytes(device));
2623 btrfs_set_device_bytes_used(leaf, dev_item,
2624 btrfs_device_get_bytes_used(device));
2625 btrfs_mark_buffer_dirty(leaf);
2626
2627 out:
2628 btrfs_free_path(path);
2629 return ret;
2630 }
2631
2632 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2633 struct btrfs_device *device, u64 new_size)
2634 {
2635 struct btrfs_super_block *super_copy =
2636 device->dev_root->fs_info->super_copy;
2637 struct btrfs_fs_devices *fs_devices;
2638 u64 old_total;
2639 u64 diff;
2640
2641 if (!device->writeable)
2642 return -EACCES;
2643
2644 lock_chunks(device->dev_root);
2645 old_total = btrfs_super_total_bytes(super_copy);
2646 diff = new_size - device->total_bytes;
2647
2648 if (new_size <= device->total_bytes ||
2649 device->is_tgtdev_for_dev_replace) {
2650 unlock_chunks(device->dev_root);
2651 return -EINVAL;
2652 }
2653
2654 fs_devices = device->dev_root->fs_info->fs_devices;
2655
2656 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2657 device->fs_devices->total_rw_bytes += diff;
2658
2659 btrfs_device_set_total_bytes(device, new_size);
2660 btrfs_device_set_disk_total_bytes(device, new_size);
2661 btrfs_clear_space_info_full(device->dev_root->fs_info);
2662 if (list_empty(&device->resized_list))
2663 list_add_tail(&device->resized_list,
2664 &fs_devices->resized_devices);
2665 unlock_chunks(device->dev_root);
2666
2667 return btrfs_update_device(trans, device);
2668 }
2669
2670 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2671 struct btrfs_root *root, u64 chunk_objectid,
2672 u64 chunk_offset)
2673 {
2674 int ret;
2675 struct btrfs_path *path;
2676 struct btrfs_key key;
2677
2678 root = root->fs_info->chunk_root;
2679 path = btrfs_alloc_path();
2680 if (!path)
2681 return -ENOMEM;
2682
2683 key.objectid = chunk_objectid;
2684 key.offset = chunk_offset;
2685 key.type = BTRFS_CHUNK_ITEM_KEY;
2686
2687 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2688 if (ret < 0)
2689 goto out;
2690 else if (ret > 0) { /* Logic error or corruption */
2691 btrfs_handle_fs_error(root->fs_info, -ENOENT,
2692 "Failed lookup while freeing chunk.");
2693 ret = -ENOENT;
2694 goto out;
2695 }
2696
2697 ret = btrfs_del_item(trans, root, path);
2698 if (ret < 0)
2699 btrfs_handle_fs_error(root->fs_info, ret,
2700 "Failed to delete chunk item.");
2701 out:
2702 btrfs_free_path(path);
2703 return ret;
2704 }
2705
2706 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2707 chunk_offset)
2708 {
2709 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2710 struct btrfs_disk_key *disk_key;
2711 struct btrfs_chunk *chunk;
2712 u8 *ptr;
2713 int ret = 0;
2714 u32 num_stripes;
2715 u32 array_size;
2716 u32 len = 0;
2717 u32 cur;
2718 struct btrfs_key key;
2719
2720 lock_chunks(root);
2721 array_size = btrfs_super_sys_array_size(super_copy);
2722
2723 ptr = super_copy->sys_chunk_array;
2724 cur = 0;
2725
2726 while (cur < array_size) {
2727 disk_key = (struct btrfs_disk_key *)ptr;
2728 btrfs_disk_key_to_cpu(&key, disk_key);
2729
2730 len = sizeof(*disk_key);
2731
2732 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2733 chunk = (struct btrfs_chunk *)(ptr + len);
2734 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2735 len += btrfs_chunk_item_size(num_stripes);
2736 } else {
2737 ret = -EIO;
2738 break;
2739 }
2740 if (key.objectid == chunk_objectid &&
2741 key.offset == chunk_offset) {
2742 memmove(ptr, ptr + len, array_size - (cur + len));
2743 array_size -= len;
2744 btrfs_set_super_sys_array_size(super_copy, array_size);
2745 } else {
2746 ptr += len;
2747 cur += len;
2748 }
2749 }
2750 unlock_chunks(root);
2751 return ret;
2752 }
2753
2754 int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
2755 struct btrfs_root *root, u64 chunk_offset)
2756 {
2757 struct extent_map_tree *em_tree;
2758 struct extent_map *em;
2759 struct btrfs_root *extent_root = root->fs_info->extent_root;
2760 struct map_lookup *map;
2761 u64 dev_extent_len = 0;
2762 u64 chunk_objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2763 int i, ret = 0;
2764 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2765
2766 /* Just in case */
2767 root = root->fs_info->chunk_root;
2768 em_tree = &root->fs_info->mapping_tree.map_tree;
2769
2770 read_lock(&em_tree->lock);
2771 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2772 read_unlock(&em_tree->lock);
2773
2774 if (!em || em->start > chunk_offset ||
2775 em->start + em->len < chunk_offset) {
2776 /*
2777 * This is a logic error, but we don't want to just rely on the
2778 * user having built with ASSERT enabled, so if ASSERT doesn't
2779 * do anything we still error out.
2780 */
2781 ASSERT(0);
2782 if (em)
2783 free_extent_map(em);
2784 return -EINVAL;
2785 }
2786 map = em->map_lookup;
2787 lock_chunks(root->fs_info->chunk_root);
2788 check_system_chunk(trans, extent_root, map->type);
2789 unlock_chunks(root->fs_info->chunk_root);
2790
2791 /*
2792 * Take the device list mutex to prevent races with the final phase of
2793 * a device replace operation that replaces the device object associated
2794 * with map stripes (dev-replace.c:btrfs_dev_replace_finishing()).
2795 */
2796 mutex_lock(&fs_devices->device_list_mutex);
2797 for (i = 0; i < map->num_stripes; i++) {
2798 struct btrfs_device *device = map->stripes[i].dev;
2799 ret = btrfs_free_dev_extent(trans, device,
2800 map->stripes[i].physical,
2801 &dev_extent_len);
2802 if (ret) {
2803 mutex_unlock(&fs_devices->device_list_mutex);
2804 btrfs_abort_transaction(trans, root, ret);
2805 goto out;
2806 }
2807
2808 if (device->bytes_used > 0) {
2809 lock_chunks(root);
2810 btrfs_device_set_bytes_used(device,
2811 device->bytes_used - dev_extent_len);
2812 spin_lock(&root->fs_info->free_chunk_lock);
2813 root->fs_info->free_chunk_space += dev_extent_len;
2814 spin_unlock(&root->fs_info->free_chunk_lock);
2815 btrfs_clear_space_info_full(root->fs_info);
2816 unlock_chunks(root);
2817 }
2818
2819 if (map->stripes[i].dev) {
2820 ret = btrfs_update_device(trans, map->stripes[i].dev);
2821 if (ret) {
2822 mutex_unlock(&fs_devices->device_list_mutex);
2823 btrfs_abort_transaction(trans, root, ret);
2824 goto out;
2825 }
2826 }
2827 }
2828 mutex_unlock(&fs_devices->device_list_mutex);
2829
2830 ret = btrfs_free_chunk(trans, root, chunk_objectid, chunk_offset);
2831 if (ret) {
2832 btrfs_abort_transaction(trans, root, ret);
2833 goto out;
2834 }
2835
2836 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2837
2838 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2839 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2840 if (ret) {
2841 btrfs_abort_transaction(trans, root, ret);
2842 goto out;
2843 }
2844 }
2845
2846 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset, em);
2847 if (ret) {
2848 btrfs_abort_transaction(trans, extent_root, ret);
2849 goto out;
2850 }
2851
2852 out:
2853 /* once for us */
2854 free_extent_map(em);
2855 return ret;
2856 }
2857
2858 static int btrfs_relocate_chunk(struct btrfs_root *root, u64 chunk_offset)
2859 {
2860 struct btrfs_root *extent_root;
2861 struct btrfs_trans_handle *trans;
2862 int ret;
2863
2864 root = root->fs_info->chunk_root;
2865 extent_root = root->fs_info->extent_root;
2866
2867 /*
2868 * Prevent races with automatic removal of unused block groups.
2869 * After we relocate and before we remove the chunk with offset
2870 * chunk_offset, automatic removal of the block group can kick in,
2871 * resulting in a failure when calling btrfs_remove_chunk() below.
2872 *
2873 * Make sure to acquire this mutex before doing a tree search (dev
2874 * or chunk trees) to find chunks. Otherwise the cleaner kthread might
2875 * call btrfs_remove_chunk() (through btrfs_delete_unused_bgs()) after
2876 * we release the path used to search the chunk/dev tree and before
2877 * the current task acquires this mutex and calls us.
2878 */
2879 ASSERT(mutex_is_locked(&root->fs_info->delete_unused_bgs_mutex));
2880
2881 ret = btrfs_can_relocate(extent_root, chunk_offset);
2882 if (ret)
2883 return -ENOSPC;
2884
2885 /* step one, relocate all the extents inside this chunk */
2886 btrfs_scrub_pause(root);
2887 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2888 btrfs_scrub_continue(root);
2889 if (ret)
2890 return ret;
2891
2892 trans = btrfs_start_trans_remove_block_group(root->fs_info,
2893 chunk_offset);
2894 if (IS_ERR(trans)) {
2895 ret = PTR_ERR(trans);
2896 btrfs_handle_fs_error(root->fs_info, ret, NULL);
2897 return ret;
2898 }
2899
2900 /*
2901 * step two, delete the device extents and the
2902 * chunk tree entries
2903 */
2904 ret = btrfs_remove_chunk(trans, root, chunk_offset);
2905 btrfs_end_transaction(trans, root);
2906 return ret;
2907 }
2908
2909 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2910 {
2911 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2912 struct btrfs_path *path;
2913 struct extent_buffer *leaf;
2914 struct btrfs_chunk *chunk;
2915 struct btrfs_key key;
2916 struct btrfs_key found_key;
2917 u64 chunk_type;
2918 bool retried = false;
2919 int failed = 0;
2920 int ret;
2921
2922 path = btrfs_alloc_path();
2923 if (!path)
2924 return -ENOMEM;
2925
2926 again:
2927 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2928 key.offset = (u64)-1;
2929 key.type = BTRFS_CHUNK_ITEM_KEY;
2930
2931 while (1) {
2932 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
2933 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2934 if (ret < 0) {
2935 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2936 goto error;
2937 }
2938 BUG_ON(ret == 0); /* Corruption */
2939
2940 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2941 key.type);
2942 if (ret)
2943 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2944 if (ret < 0)
2945 goto error;
2946 if (ret > 0)
2947 break;
2948
2949 leaf = path->nodes[0];
2950 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2951
2952 chunk = btrfs_item_ptr(leaf, path->slots[0],
2953 struct btrfs_chunk);
2954 chunk_type = btrfs_chunk_type(leaf, chunk);
2955 btrfs_release_path(path);
2956
2957 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2958 ret = btrfs_relocate_chunk(chunk_root,
2959 found_key.offset);
2960 if (ret == -ENOSPC)
2961 failed++;
2962 else
2963 BUG_ON(ret);
2964 }
2965 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
2966
2967 if (found_key.offset == 0)
2968 break;
2969 key.offset = found_key.offset - 1;
2970 }
2971 ret = 0;
2972 if (failed && !retried) {
2973 failed = 0;
2974 retried = true;
2975 goto again;
2976 } else if (WARN_ON(failed && retried)) {
2977 ret = -ENOSPC;
2978 }
2979 error:
2980 btrfs_free_path(path);
2981 return ret;
2982 }
2983
2984 static int insert_balance_item(struct btrfs_root *root,
2985 struct btrfs_balance_control *bctl)
2986 {
2987 struct btrfs_trans_handle *trans;
2988 struct btrfs_balance_item *item;
2989 struct btrfs_disk_balance_args disk_bargs;
2990 struct btrfs_path *path;
2991 struct extent_buffer *leaf;
2992 struct btrfs_key key;
2993 int ret, err;
2994
2995 path = btrfs_alloc_path();
2996 if (!path)
2997 return -ENOMEM;
2998
2999 trans = btrfs_start_transaction(root, 0);
3000 if (IS_ERR(trans)) {
3001 btrfs_free_path(path);
3002 return PTR_ERR(trans);
3003 }
3004
3005 key.objectid = BTRFS_BALANCE_OBJECTID;
3006 key.type = BTRFS_TEMPORARY_ITEM_KEY;
3007 key.offset = 0;
3008
3009 ret = btrfs_insert_empty_item(trans, root, path, &key,
3010 sizeof(*item));
3011 if (ret)
3012 goto out;
3013
3014 leaf = path->nodes[0];
3015 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3016
3017 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
3018
3019 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
3020 btrfs_set_balance_data(leaf, item, &disk_bargs);
3021 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
3022 btrfs_set_balance_meta(leaf, item, &disk_bargs);
3023 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
3024 btrfs_set_balance_sys(leaf, item, &disk_bargs);
3025
3026 btrfs_set_balance_flags(leaf, item, bctl->flags);
3027
3028 btrfs_mark_buffer_dirty(leaf);
3029 out:
3030 btrfs_free_path(path);
3031 err = btrfs_commit_transaction(trans, root);
3032 if (err && !ret)
3033 ret = err;
3034 return ret;
3035 }
3036
3037 static int del_balance_item(struct btrfs_root *root)
3038 {
3039 struct btrfs_trans_handle *trans;
3040 struct btrfs_path *path;
3041 struct btrfs_key key;
3042 int ret, err;
3043
3044 path = btrfs_alloc_path();
3045 if (!path)
3046 return -ENOMEM;
3047
3048 trans = btrfs_start_transaction(root, 0);
3049 if (IS_ERR(trans)) {
3050 btrfs_free_path(path);
3051 return PTR_ERR(trans);
3052 }
3053
3054 key.objectid = BTRFS_BALANCE_OBJECTID;
3055 key.type = BTRFS_TEMPORARY_ITEM_KEY;
3056 key.offset = 0;
3057
3058 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
3059 if (ret < 0)
3060 goto out;
3061 if (ret > 0) {
3062 ret = -ENOENT;
3063 goto out;
3064 }
3065
3066 ret = btrfs_del_item(trans, root, path);
3067 out:
3068 btrfs_free_path(path);
3069 err = btrfs_commit_transaction(trans, root);
3070 if (err && !ret)
3071 ret = err;
3072 return ret;
3073 }
3074
3075 /*
3076 * This is a heuristic used to reduce the number of chunks balanced on
3077 * resume after balance was interrupted.
3078 */
3079 static void update_balance_args(struct btrfs_balance_control *bctl)
3080 {
3081 /*
3082 * Turn on soft mode for chunk types that were being converted.
3083 */
3084 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
3085 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
3086 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
3087 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
3088 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
3089 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
3090
3091 /*
3092 * Turn on usage filter if is not already used. The idea is
3093 * that chunks that we have already balanced should be
3094 * reasonably full. Don't do it for chunks that are being
3095 * converted - that will keep us from relocating unconverted
3096 * (albeit full) chunks.
3097 */
3098 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3099 !(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3100 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3101 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
3102 bctl->data.usage = 90;
3103 }
3104 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3105 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3106 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3107 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
3108 bctl->sys.usage = 90;
3109 }
3110 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
3111 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3112 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
3113 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
3114 bctl->meta.usage = 90;
3115 }
3116 }
3117
3118 /*
3119 * Should be called with both balance and volume mutexes held to
3120 * serialize other volume operations (add_dev/rm_dev/resize) with
3121 * restriper. Same goes for unset_balance_control.
3122 */
3123 static void set_balance_control(struct btrfs_balance_control *bctl)
3124 {
3125 struct btrfs_fs_info *fs_info = bctl->fs_info;
3126
3127 BUG_ON(fs_info->balance_ctl);
3128
3129 spin_lock(&fs_info->balance_lock);
3130 fs_info->balance_ctl = bctl;
3131 spin_unlock(&fs_info->balance_lock);
3132 }
3133
3134 static void unset_balance_control(struct btrfs_fs_info *fs_info)
3135 {
3136 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3137
3138 BUG_ON(!fs_info->balance_ctl);
3139
3140 spin_lock(&fs_info->balance_lock);
3141 fs_info->balance_ctl = NULL;
3142 spin_unlock(&fs_info->balance_lock);
3143
3144 kfree(bctl);
3145 }
3146
3147 /*
3148 * Balance filters. Return 1 if chunk should be filtered out
3149 * (should not be balanced).
3150 */
3151 static int chunk_profiles_filter(u64 chunk_type,
3152 struct btrfs_balance_args *bargs)
3153 {
3154 chunk_type = chunk_to_extended(chunk_type) &
3155 BTRFS_EXTENDED_PROFILE_MASK;
3156
3157 if (bargs->profiles & chunk_type)
3158 return 0;
3159
3160 return 1;
3161 }
3162
3163 static int chunk_usage_range_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
3164 struct btrfs_balance_args *bargs)
3165 {
3166 struct btrfs_block_group_cache *cache;
3167 u64 chunk_used;
3168 u64 user_thresh_min;
3169 u64 user_thresh_max;
3170 int ret = 1;
3171
3172 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3173 chunk_used = btrfs_block_group_used(&cache->item);
3174
3175 if (bargs->usage_min == 0)
3176 user_thresh_min = 0;
3177 else
3178 user_thresh_min = div_factor_fine(cache->key.offset,
3179 bargs->usage_min);
3180
3181 if (bargs->usage_max == 0)
3182 user_thresh_max = 1;
3183 else if (bargs->usage_max > 100)
3184 user_thresh_max = cache->key.offset;
3185 else
3186 user_thresh_max = div_factor_fine(cache->key.offset,
3187 bargs->usage_max);
3188
3189 if (user_thresh_min <= chunk_used && chunk_used < user_thresh_max)
3190 ret = 0;
3191
3192 btrfs_put_block_group(cache);
3193 return ret;
3194 }
3195
3196 static int chunk_usage_filter(struct btrfs_fs_info *fs_info,
3197 u64 chunk_offset, struct btrfs_balance_args *bargs)
3198 {
3199 struct btrfs_block_group_cache *cache;
3200 u64 chunk_used, user_thresh;
3201 int ret = 1;
3202
3203 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3204 chunk_used = btrfs_block_group_used(&cache->item);
3205
3206 if (bargs->usage_min == 0)
3207 user_thresh = 1;
3208 else if (bargs->usage > 100)
3209 user_thresh = cache->key.offset;
3210 else
3211 user_thresh = div_factor_fine(cache->key.offset,
3212 bargs->usage);
3213
3214 if (chunk_used < user_thresh)
3215 ret = 0;
3216
3217 btrfs_put_block_group(cache);
3218 return ret;
3219 }
3220
3221 static int chunk_devid_filter(struct extent_buffer *leaf,
3222 struct btrfs_chunk *chunk,
3223 struct btrfs_balance_args *bargs)
3224 {
3225 struct btrfs_stripe *stripe;
3226 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3227 int i;
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 return 0;
3233 }
3234
3235 return 1;
3236 }
3237
3238 /* [pstart, pend) */
3239 static int chunk_drange_filter(struct extent_buffer *leaf,
3240 struct btrfs_chunk *chunk,
3241 u64 chunk_offset,
3242 struct btrfs_balance_args *bargs)
3243 {
3244 struct btrfs_stripe *stripe;
3245 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3246 u64 stripe_offset;
3247 u64 stripe_length;
3248 int factor;
3249 int i;
3250
3251 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
3252 return 0;
3253
3254 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
3255 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
3256 factor = num_stripes / 2;
3257 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
3258 factor = num_stripes - 1;
3259 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
3260 factor = num_stripes - 2;
3261 } else {
3262 factor = num_stripes;
3263 }
3264
3265 for (i = 0; i < num_stripes; i++) {
3266 stripe = btrfs_stripe_nr(chunk, i);
3267 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
3268 continue;
3269
3270 stripe_offset = btrfs_stripe_offset(leaf, stripe);
3271 stripe_length = btrfs_chunk_length(leaf, chunk);
3272 stripe_length = div_u64(stripe_length, factor);
3273
3274 if (stripe_offset < bargs->pend &&
3275 stripe_offset + stripe_length > bargs->pstart)
3276 return 0;
3277 }
3278
3279 return 1;
3280 }
3281
3282 /* [vstart, vend) */
3283 static int chunk_vrange_filter(struct extent_buffer *leaf,
3284 struct btrfs_chunk *chunk,
3285 u64 chunk_offset,
3286 struct btrfs_balance_args *bargs)
3287 {
3288 if (chunk_offset < bargs->vend &&
3289 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
3290 /* at least part of the chunk is inside this vrange */
3291 return 0;
3292
3293 return 1;
3294 }
3295
3296 static int chunk_stripes_range_filter(struct extent_buffer *leaf,
3297 struct btrfs_chunk *chunk,
3298 struct btrfs_balance_args *bargs)
3299 {
3300 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
3301
3302 if (bargs->stripes_min <= num_stripes
3303 && num_stripes <= bargs->stripes_max)
3304 return 0;
3305
3306 return 1;
3307 }
3308
3309 static int chunk_soft_convert_filter(u64 chunk_type,
3310 struct btrfs_balance_args *bargs)
3311 {
3312 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
3313 return 0;
3314
3315 chunk_type = chunk_to_extended(chunk_type) &
3316 BTRFS_EXTENDED_PROFILE_MASK;
3317
3318 if (bargs->target == chunk_type)
3319 return 1;
3320
3321 return 0;
3322 }
3323
3324 static int should_balance_chunk(struct btrfs_root *root,
3325 struct extent_buffer *leaf,
3326 struct btrfs_chunk *chunk, u64 chunk_offset)
3327 {
3328 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
3329 struct btrfs_balance_args *bargs = NULL;
3330 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
3331
3332 /* type filter */
3333 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
3334 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
3335 return 0;
3336 }
3337
3338 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3339 bargs = &bctl->data;
3340 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3341 bargs = &bctl->sys;
3342 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3343 bargs = &bctl->meta;
3344
3345 /* profiles filter */
3346 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
3347 chunk_profiles_filter(chunk_type, bargs)) {
3348 return 0;
3349 }
3350
3351 /* usage filter */
3352 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
3353 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
3354 return 0;
3355 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE_RANGE) &&
3356 chunk_usage_range_filter(bctl->fs_info, chunk_offset, bargs)) {
3357 return 0;
3358 }
3359
3360 /* devid filter */
3361 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
3362 chunk_devid_filter(leaf, chunk, bargs)) {
3363 return 0;
3364 }
3365
3366 /* drange filter, makes sense only with devid filter */
3367 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
3368 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
3369 return 0;
3370 }
3371
3372 /* vrange filter */
3373 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
3374 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
3375 return 0;
3376 }
3377
3378 /* stripes filter */
3379 if ((bargs->flags & BTRFS_BALANCE_ARGS_STRIPES_RANGE) &&
3380 chunk_stripes_range_filter(leaf, chunk, bargs)) {
3381 return 0;
3382 }
3383
3384 /* soft profile changing mode */
3385 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
3386 chunk_soft_convert_filter(chunk_type, bargs)) {
3387 return 0;
3388 }
3389
3390 /*
3391 * limited by count, must be the last filter
3392 */
3393 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
3394 if (bargs->limit == 0)
3395 return 0;
3396 else
3397 bargs->limit--;
3398 } else if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT_RANGE)) {
3399 /*
3400 * Same logic as the 'limit' filter; the minimum cannot be
3401 * determined here because we do not have the global information
3402 * about the count of all chunks that satisfy the filters.
3403 */
3404 if (bargs->limit_max == 0)
3405 return 0;
3406 else
3407 bargs->limit_max--;
3408 }
3409
3410 return 1;
3411 }
3412
3413 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
3414 {
3415 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3416 struct btrfs_root *chunk_root = fs_info->chunk_root;
3417 struct btrfs_root *dev_root = fs_info->dev_root;
3418 struct list_head *devices;
3419 struct btrfs_device *device;
3420 u64 old_size;
3421 u64 size_to_free;
3422 u64 chunk_type;
3423 struct btrfs_chunk *chunk;
3424 struct btrfs_path *path;
3425 struct btrfs_key key;
3426 struct btrfs_key found_key;
3427 struct btrfs_trans_handle *trans;
3428 struct extent_buffer *leaf;
3429 int slot;
3430 int ret;
3431 int enospc_errors = 0;
3432 bool counting = true;
3433 /* The single value limit and min/max limits use the same bytes in the */
3434 u64 limit_data = bctl->data.limit;
3435 u64 limit_meta = bctl->meta.limit;
3436 u64 limit_sys = bctl->sys.limit;
3437 u32 count_data = 0;
3438 u32 count_meta = 0;
3439 u32 count_sys = 0;
3440 int chunk_reserved = 0;
3441 u64 bytes_used = 0;
3442
3443 /* step one make some room on all the devices */
3444 devices = &fs_info->fs_devices->devices;
3445 list_for_each_entry(device, devices, dev_list) {
3446 old_size = btrfs_device_get_total_bytes(device);
3447 size_to_free = div_factor(old_size, 1);
3448 size_to_free = min_t(u64, size_to_free, SZ_1M);
3449 if (!device->writeable ||
3450 btrfs_device_get_total_bytes(device) -
3451 btrfs_device_get_bytes_used(device) > size_to_free ||
3452 device->is_tgtdev_for_dev_replace)
3453 continue;
3454
3455 ret = btrfs_shrink_device(device, old_size - size_to_free);
3456 if (ret == -ENOSPC)
3457 break;
3458 BUG_ON(ret);
3459
3460 trans = btrfs_start_transaction(dev_root, 0);
3461 BUG_ON(IS_ERR(trans));
3462
3463 ret = btrfs_grow_device(trans, device, old_size);
3464 BUG_ON(ret);
3465
3466 btrfs_end_transaction(trans, dev_root);
3467 }
3468
3469 /* step two, relocate all the chunks */
3470 path = btrfs_alloc_path();
3471 if (!path) {
3472 ret = -ENOMEM;
3473 goto error;
3474 }
3475
3476 /* zero out stat counters */
3477 spin_lock(&fs_info->balance_lock);
3478 memset(&bctl->stat, 0, sizeof(bctl->stat));
3479 spin_unlock(&fs_info->balance_lock);
3480 again:
3481 if (!counting) {
3482 /*
3483 * The single value limit and min/max limits use the same bytes
3484 * in the
3485 */
3486 bctl->data.limit = limit_data;
3487 bctl->meta.limit = limit_meta;
3488 bctl->sys.limit = limit_sys;
3489 }
3490 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3491 key.offset = (u64)-1;
3492 key.type = BTRFS_CHUNK_ITEM_KEY;
3493
3494 while (1) {
3495 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
3496 atomic_read(&fs_info->balance_cancel_req)) {
3497 ret = -ECANCELED;
3498 goto error;
3499 }
3500
3501 mutex_lock(&fs_info->delete_unused_bgs_mutex);
3502 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3503 if (ret < 0) {
3504 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3505 goto error;
3506 }
3507
3508 /*
3509 * this shouldn't happen, it means the last relocate
3510 * failed
3511 */
3512 if (ret == 0)
3513 BUG(); /* FIXME break ? */
3514
3515 ret = btrfs_previous_item(chunk_root, path, 0,
3516 BTRFS_CHUNK_ITEM_KEY);
3517 if (ret) {
3518 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3519 ret = 0;
3520 break;
3521 }
3522
3523 leaf = path->nodes[0];
3524 slot = path->slots[0];
3525 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3526
3527 if (found_key.objectid != key.objectid) {
3528 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3529 break;
3530 }
3531
3532 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3533 chunk_type = btrfs_chunk_type(leaf, chunk);
3534
3535 if (!counting) {
3536 spin_lock(&fs_info->balance_lock);
3537 bctl->stat.considered++;
3538 spin_unlock(&fs_info->balance_lock);
3539 }
3540
3541 ret = should_balance_chunk(chunk_root, leaf, chunk,
3542 found_key.offset);
3543
3544 btrfs_release_path(path);
3545 if (!ret) {
3546 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3547 goto loop;
3548 }
3549
3550 if (counting) {
3551 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3552 spin_lock(&fs_info->balance_lock);
3553 bctl->stat.expected++;
3554 spin_unlock(&fs_info->balance_lock);
3555
3556 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
3557 count_data++;
3558 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
3559 count_sys++;
3560 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
3561 count_meta++;
3562
3563 goto loop;
3564 }
3565
3566 /*
3567 * Apply limit_min filter, no need to check if the LIMITS
3568 * filter is used, limit_min is 0 by default
3569 */
3570 if (((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
3571 count_data < bctl->data.limit_min)
3572 || ((chunk_type & BTRFS_BLOCK_GROUP_METADATA) &&
3573 count_meta < bctl->meta.limit_min)
3574 || ((chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) &&
3575 count_sys < bctl->sys.limit_min)) {
3576 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3577 goto loop;
3578 }
3579
3580 ASSERT(fs_info->data_sinfo);
3581 spin_lock(&fs_info->data_sinfo->lock);
3582 bytes_used = fs_info->data_sinfo->bytes_used;
3583 spin_unlock(&fs_info->data_sinfo->lock);
3584
3585 if ((chunk_type & BTRFS_BLOCK_GROUP_DATA) &&
3586 !chunk_reserved && !bytes_used) {
3587 trans = btrfs_start_transaction(chunk_root, 0);
3588 if (IS_ERR(trans)) {
3589 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3590 ret = PTR_ERR(trans);
3591 goto error;
3592 }
3593
3594 ret = btrfs_force_chunk_alloc(trans, chunk_root,
3595 BTRFS_BLOCK_GROUP_DATA);
3596 btrfs_end_transaction(trans, chunk_root);
3597 if (ret < 0) {
3598 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3599 goto error;
3600 }
3601 chunk_reserved = 1;
3602 }
3603
3604 ret = btrfs_relocate_chunk(chunk_root,
3605 found_key.offset);
3606 mutex_unlock(&fs_info->delete_unused_bgs_mutex);
3607 if (ret && ret != -ENOSPC)
3608 goto error;
3609 if (ret == -ENOSPC) {
3610 enospc_errors++;
3611 } else {
3612 spin_lock(&fs_info->balance_lock);
3613 bctl->stat.completed++;
3614 spin_unlock(&fs_info->balance_lock);
3615 }
3616 loop:
3617 if (found_key.offset == 0)
3618 break;
3619 key.offset = found_key.offset - 1;
3620 }
3621
3622 if (counting) {
3623 btrfs_release_path(path);
3624 counting = false;
3625 goto again;
3626 }
3627 error:
3628 btrfs_free_path(path);
3629 if (enospc_errors) {
3630 btrfs_info(fs_info, "%d enospc errors during balance",
3631 enospc_errors);
3632 if (!ret)
3633 ret = -ENOSPC;
3634 }
3635
3636 return ret;
3637 }
3638
3639 /**
3640 * alloc_profile_is_valid - see if a given profile is valid and reduced
3641 * @flags: profile to validate
3642 * @extended: if true @flags is treated as an extended profile
3643 */
3644 static int alloc_profile_is_valid(u64 flags, int extended)
3645 {
3646 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
3647 BTRFS_BLOCK_GROUP_PROFILE_MASK);
3648
3649 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
3650
3651 /* 1) check that all other bits are zeroed */
3652 if (flags & ~mask)
3653 return 0;
3654
3655 /* 2) see if profile is reduced */
3656 if (flags == 0)
3657 return !extended; /* "0" is valid for usual profiles */
3658
3659 /* true if exactly one bit set */
3660 return (flags & (flags - 1)) == 0;
3661 }
3662
3663 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
3664 {
3665 /* cancel requested || normal exit path */
3666 return atomic_read(&fs_info->balance_cancel_req) ||
3667 (atomic_read(&fs_info->balance_pause_req) == 0 &&
3668 atomic_read(&fs_info->balance_cancel_req) == 0);
3669 }
3670
3671 static void __cancel_balance(struct btrfs_fs_info *fs_info)
3672 {
3673 int ret;
3674
3675 unset_balance_control(fs_info);
3676 ret = del_balance_item(fs_info->tree_root);
3677 if (ret)
3678 btrfs_handle_fs_error(fs_info, ret, NULL);
3679
3680 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3681 }
3682
3683 /* Non-zero return value signifies invalidity */
3684 static inline int validate_convert_profile(struct btrfs_balance_args *bctl_arg,
3685 u64 allowed)
3686 {
3687 return ((bctl_arg->flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3688 (!alloc_profile_is_valid(bctl_arg->target, 1) ||
3689 (bctl_arg->target & ~allowed)));
3690 }
3691
3692 /*
3693 * Should be called with both balance and volume mutexes held
3694 */
3695 int btrfs_balance(struct btrfs_balance_control *bctl,
3696 struct btrfs_ioctl_balance_args *bargs)
3697 {
3698 struct btrfs_fs_info *fs_info = bctl->fs_info;
3699 u64 allowed;
3700 int mixed = 0;
3701 int ret;
3702 u64 num_devices;
3703 unsigned seq;
3704
3705 if (btrfs_fs_closing(fs_info) ||
3706 atomic_read(&fs_info->balance_pause_req) ||
3707 atomic_read(&fs_info->balance_cancel_req)) {
3708 ret = -EINVAL;
3709 goto out;
3710 }
3711
3712 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3713 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3714 mixed = 1;
3715
3716 /*
3717 * In case of mixed groups both data and meta should be picked,
3718 * and identical options should be given for both of them.
3719 */
3720 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3721 if (mixed && (bctl->flags & allowed)) {
3722 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3723 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3724 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3725 btrfs_err(fs_info, "with mixed groups data and "
3726 "metadata balance options must be the same");
3727 ret = -EINVAL;
3728 goto out;
3729 }
3730 }
3731
3732 num_devices = fs_info->fs_devices->num_devices;
3733 btrfs_dev_replace_lock(&fs_info->dev_replace, 0);
3734 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3735 BUG_ON(num_devices < 1);
3736 num_devices--;
3737 }
3738 btrfs_dev_replace_unlock(&fs_info->dev_replace, 0);
3739 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE | BTRFS_BLOCK_GROUP_DUP;
3740 if (num_devices > 1)
3741 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3742 if (num_devices > 2)
3743 allowed |= BTRFS_BLOCK_GROUP_RAID5;
3744 if (num_devices > 3)
3745 allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
3746 BTRFS_BLOCK_GROUP_RAID6);
3747 if (validate_convert_profile(&bctl->data, allowed)) {
3748 btrfs_err(fs_info, "unable to start balance with target "
3749 "data profile %llu",
3750 bctl->data.target);
3751 ret = -EINVAL;
3752 goto out;
3753 }
3754 if (validate_convert_profile(&bctl->meta, allowed)) {
3755 btrfs_err(fs_info,
3756 "unable to start balance with target metadata profile %llu",
3757 bctl->meta.target);
3758 ret = -EINVAL;
3759 goto out;
3760 }
3761 if (validate_convert_profile(&bctl->sys, allowed)) {
3762 btrfs_err(fs_info,
3763 "unable to start balance with target system profile %llu",
3764 bctl->sys.target);
3765 ret = -EINVAL;
3766 goto out;
3767 }
3768
3769 /* allow to reduce meta or sys integrity only if force set */
3770 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3771 BTRFS_BLOCK_GROUP_RAID10 |
3772 BTRFS_BLOCK_GROUP_RAID5 |
3773 BTRFS_BLOCK_GROUP_RAID6;
3774 do {
3775 seq = read_seqbegin(&fs_info->profiles_lock);
3776
3777 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3778 (fs_info->avail_system_alloc_bits & allowed) &&
3779 !(bctl->sys.target & allowed)) ||
3780 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3781 (fs_info->avail_metadata_alloc_bits & allowed) &&
3782 !(bctl->meta.target & allowed))) {
3783 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3784 btrfs_info(fs_info, "force reducing metadata integrity");
3785 } else {
3786 btrfs_err(fs_info, "balance will reduce metadata "
3787 "integrity, use force if you want this");
3788 ret = -EINVAL;
3789 goto out;
3790 }
3791 }
3792 } while (read_seqretry(&fs_info->profiles_lock, seq));
3793
3794 if (btrfs_get_num_tolerated_disk_barrier_failures(bctl->meta.target) <
3795 btrfs_get_num_tolerated_disk_barrier_failures(bctl->data.target)) {
3796 btrfs_warn(fs_info,
3797 "metadata profile 0x%llx has lower redundancy than data profile 0x%llx",
3798 bctl->meta.target, bctl->data.target);
3799 }
3800
3801 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3802 fs_info->num_tolerated_disk_barrier_failures = min(
3803 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info),
3804 btrfs_get_num_tolerated_disk_barrier_failures(
3805 bctl->sys.target));
3806 }
3807
3808 ret = insert_balance_item(fs_info->tree_root, bctl);
3809 if (ret && ret != -EEXIST)
3810 goto out;
3811
3812 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3813 BUG_ON(ret == -EEXIST);
3814 set_balance_control(bctl);
3815 } else {
3816 BUG_ON(ret != -EEXIST);
3817 spin_lock(&fs_info->balance_lock);
3818 update_balance_args(bctl);
3819 spin_unlock(&fs_info->balance_lock);
3820 }
3821
3822 atomic_inc(&fs_info->balance_running);
3823 mutex_unlock(&fs_info->balance_mutex);
3824
3825 ret = __btrfs_balance(fs_info);
3826
3827 mutex_lock(&fs_info->balance_mutex);
3828 atomic_dec(&fs_info->balance_running);
3829
3830 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3831 fs_info->num_tolerated_disk_barrier_failures =
3832 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3833 }
3834
3835 if (bargs) {
3836 memset(bargs, 0, sizeof(*bargs));
3837 update_ioctl_balance_args(fs_info, 0, bargs);
3838 }
3839
3840 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3841 balance_need_close(fs_info)) {
3842 __cancel_balance(fs_info);
3843 }
3844
3845 wake_up(&fs_info->balance_wait_q);
3846
3847 return ret;
3848 out:
3849 if (bctl->flags & BTRFS_BALANCE_RESUME)
3850 __cancel_balance(fs_info);
3851 else {
3852 kfree(bctl);
3853 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3854 }
3855 return ret;
3856 }
3857
3858 static int balance_kthread(void *data)
3859 {
3860 struct btrfs_fs_info *fs_info = data;
3861 int ret = 0;
3862
3863 mutex_lock(&fs_info->volume_mutex);
3864 mutex_lock(&fs_info->balance_mutex);
3865
3866 if (fs_info->balance_ctl) {
3867 btrfs_info(fs_info, "continuing balance");
3868 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3869 }
3870
3871 mutex_unlock(&fs_info->balance_mutex);
3872 mutex_unlock(&fs_info->volume_mutex);
3873
3874 return ret;
3875 }
3876
3877 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3878 {
3879 struct task_struct *tsk;
3880
3881 spin_lock(&fs_info->balance_lock);
3882 if (!fs_info->balance_ctl) {
3883 spin_unlock(&fs_info->balance_lock);
3884 return 0;
3885 }
3886 spin_unlock(&fs_info->balance_lock);
3887
3888 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3889 btrfs_info(fs_info, "force skipping balance");
3890 return 0;
3891 }
3892
3893 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3894 return PTR_ERR_OR_ZERO(tsk);
3895 }
3896
3897 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3898 {
3899 struct btrfs_balance_control *bctl;
3900 struct btrfs_balance_item *item;
3901 struct btrfs_disk_balance_args disk_bargs;
3902 struct btrfs_path *path;
3903 struct extent_buffer *leaf;
3904 struct btrfs_key key;
3905 int ret;
3906
3907 path = btrfs_alloc_path();
3908 if (!path)
3909 return -ENOMEM;
3910
3911 key.objectid = BTRFS_BALANCE_OBJECTID;
3912 key.type = BTRFS_TEMPORARY_ITEM_KEY;
3913 key.offset = 0;
3914
3915 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3916 if (ret < 0)
3917 goto out;
3918 if (ret > 0) { /* ret = -ENOENT; */
3919 ret = 0;
3920 goto out;
3921 }
3922
3923 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3924 if (!bctl) {
3925 ret = -ENOMEM;
3926 goto out;
3927 }
3928
3929 leaf = path->nodes[0];
3930 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3931
3932 bctl->fs_info = fs_info;
3933 bctl->flags = btrfs_balance_flags(leaf, item);
3934 bctl->flags |= BTRFS_BALANCE_RESUME;
3935
3936 btrfs_balance_data(leaf, item, &disk_bargs);
3937 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3938 btrfs_balance_meta(leaf, item, &disk_bargs);
3939 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3940 btrfs_balance_sys(leaf, item, &disk_bargs);
3941 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3942
3943 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3944
3945 mutex_lock(&fs_info->volume_mutex);
3946 mutex_lock(&fs_info->balance_mutex);
3947
3948 set_balance_control(bctl);
3949
3950 mutex_unlock(&fs_info->balance_mutex);
3951 mutex_unlock(&fs_info->volume_mutex);
3952 out:
3953 btrfs_free_path(path);
3954 return ret;
3955 }
3956
3957 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3958 {
3959 int ret = 0;
3960
3961 mutex_lock(&fs_info->balance_mutex);
3962 if (!fs_info->balance_ctl) {
3963 mutex_unlock(&fs_info->balance_mutex);
3964 return -ENOTCONN;
3965 }
3966
3967 if (atomic_read(&fs_info->balance_running)) {
3968 atomic_inc(&fs_info->balance_pause_req);
3969 mutex_unlock(&fs_info->balance_mutex);
3970
3971 wait_event(fs_info->balance_wait_q,
3972 atomic_read(&fs_info->balance_running) == 0);
3973
3974 mutex_lock(&fs_info->balance_mutex);
3975 /* we are good with balance_ctl ripped off from under us */
3976 BUG_ON(atomic_read(&fs_info->balance_running));
3977 atomic_dec(&fs_info->balance_pause_req);
3978 } else {
3979 ret = -ENOTCONN;
3980 }
3981
3982 mutex_unlock(&fs_info->balance_mutex);
3983 return ret;
3984 }
3985
3986 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3987 {
3988 if (fs_info->sb->s_flags & MS_RDONLY)
3989 return -EROFS;
3990
3991 mutex_lock(&fs_info->balance_mutex);
3992 if (!fs_info->balance_ctl) {
3993 mutex_unlock(&fs_info->balance_mutex);
3994 return -ENOTCONN;
3995 }
3996
3997 atomic_inc(&fs_info->balance_cancel_req);
3998 /*
3999 * if we are running just wait and return, balance item is
4000 * deleted in btrfs_balance in this case
4001 */
4002 if (atomic_read(&fs_info->balance_running)) {
4003 mutex_unlock(&fs_info->balance_mutex);
4004 wait_event(fs_info->balance_wait_q,
4005 atomic_read(&fs_info->balance_running) == 0);
4006 mutex_lock(&fs_info->balance_mutex);
4007 } else {
4008 /* __cancel_balance needs volume_mutex */
4009 mutex_unlock(&fs_info->balance_mutex);
4010 mutex_lock(&fs_info->volume_mutex);
4011 mutex_lock(&fs_info->balance_mutex);
4012
4013 if (fs_info->balance_ctl)
4014 __cancel_balance(fs_info);
4015
4016 mutex_unlock(&fs_info->volume_mutex);
4017 }
4018
4019 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
4020 atomic_dec(&fs_info->balance_cancel_req);
4021 mutex_unlock(&fs_info->balance_mutex);
4022 return 0;
4023 }
4024
4025 static int btrfs_uuid_scan_kthread(void *data)
4026 {
4027 struct btrfs_fs_info *fs_info = data;
4028 struct btrfs_root *root = fs_info->tree_root;
4029 struct btrfs_key key;
4030 struct btrfs_key max_key;
4031 struct btrfs_path *path = NULL;
4032 int ret = 0;
4033 struct extent_buffer *eb;
4034 int slot;
4035 struct btrfs_root_item root_item;
4036 u32 item_size;
4037 struct btrfs_trans_handle *trans = NULL;
4038
4039 path = btrfs_alloc_path();
4040 if (!path) {
4041 ret = -ENOMEM;
4042 goto out;
4043 }
4044
4045 key.objectid = 0;
4046 key.type = BTRFS_ROOT_ITEM_KEY;
4047 key.offset = 0;
4048
4049 max_key.objectid = (u64)-1;
4050 max_key.type = BTRFS_ROOT_ITEM_KEY;
4051 max_key.offset = (u64)-1;
4052
4053 while (1) {
4054 ret = btrfs_search_forward(root, &key, path, 0);
4055 if (ret) {
4056 if (ret > 0)
4057 ret = 0;
4058 break;
4059 }
4060
4061 if (key.type != BTRFS_ROOT_ITEM_KEY ||
4062 (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
4063 key.objectid != BTRFS_FS_TREE_OBJECTID) ||
4064 key.objectid > BTRFS_LAST_FREE_OBJECTID)
4065 goto skip;
4066
4067 eb = path->nodes[0];
4068 slot = path->slots[0];
4069 item_size = btrfs_item_size_nr(eb, slot);
4070 if (item_size < sizeof(root_item))
4071 goto skip;
4072
4073 read_extent_buffer(eb, &root_item,
4074 btrfs_item_ptr_offset(eb, slot),
4075 (int)sizeof(root_item));
4076 if (btrfs_root_refs(&root_item) == 0)
4077 goto skip;
4078
4079 if (!btrfs_is_empty_uuid(root_item.uuid) ||
4080 !btrfs_is_empty_uuid(root_item.received_uuid)) {
4081 if (trans)
4082 goto update_tree;
4083
4084 btrfs_release_path(path);
4085 /*
4086 * 1 - subvol uuid item
4087 * 1 - received_subvol uuid item
4088 */
4089 trans = btrfs_start_transaction(fs_info->uuid_root, 2);
4090 if (IS_ERR(trans)) {
4091 ret = PTR_ERR(trans);
4092 break;
4093 }
4094 continue;
4095 } else {
4096 goto skip;
4097 }
4098 update_tree:
4099 if (!btrfs_is_empty_uuid(root_item.uuid)) {
4100 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
4101 root_item.uuid,
4102 BTRFS_UUID_KEY_SUBVOL,
4103 key.objectid);
4104 if (ret < 0) {
4105 btrfs_warn(fs_info, "uuid_tree_add failed %d",
4106 ret);
4107 break;
4108 }
4109 }
4110
4111 if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
4112 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
4113 root_item.received_uuid,
4114 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4115 key.objectid);
4116 if (ret < 0) {
4117 btrfs_warn(fs_info, "uuid_tree_add failed %d",
4118 ret);
4119 break;
4120 }
4121 }
4122
4123 skip:
4124 if (trans) {
4125 ret = btrfs_end_transaction(trans, fs_info->uuid_root);
4126 trans = NULL;
4127 if (ret)
4128 break;
4129 }
4130
4131 btrfs_release_path(path);
4132 if (key.offset < (u64)-1) {
4133 key.offset++;
4134 } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
4135 key.offset = 0;
4136 key.type = BTRFS_ROOT_ITEM_KEY;
4137 } else if (key.objectid < (u64)-1) {
4138 key.offset = 0;
4139 key.type = BTRFS_ROOT_ITEM_KEY;
4140 key.objectid++;
4141 } else {
4142 break;
4143 }
4144 cond_resched();
4145 }
4146
4147 out:
4148 btrfs_free_path(path);
4149 if (trans && !IS_ERR(trans))
4150 btrfs_end_transaction(trans, fs_info->uuid_root);
4151 if (ret)
4152 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
4153 else
4154 fs_info->update_uuid_tree_gen = 1;
4155 up(&fs_info->uuid_tree_rescan_sem);
4156 return 0;
4157 }
4158
4159 /*
4160 * Callback for btrfs_uuid_tree_iterate().
4161 * returns:
4162 * 0 check succeeded, the entry is not outdated.
4163 * < 0 if an error occurred.
4164 * > 0 if the check failed, which means the caller shall remove the entry.
4165 */
4166 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
4167 u8 *uuid, u8 type, u64 subid)
4168 {
4169 struct btrfs_key key;
4170 int ret = 0;
4171 struct btrfs_root *subvol_root;
4172
4173 if (type != BTRFS_UUID_KEY_SUBVOL &&
4174 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
4175 goto out;
4176
4177 key.objectid = subid;
4178 key.type = BTRFS_ROOT_ITEM_KEY;
4179 key.offset = (u64)-1;
4180 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
4181 if (IS_ERR(subvol_root)) {
4182 ret = PTR_ERR(subvol_root);
4183 if (ret == -ENOENT)
4184 ret = 1;
4185 goto out;
4186 }
4187
4188 switch (type) {
4189 case BTRFS_UUID_KEY_SUBVOL:
4190 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
4191 ret = 1;
4192 break;
4193 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
4194 if (memcmp(uuid, subvol_root->root_item.received_uuid,
4195 BTRFS_UUID_SIZE))
4196 ret = 1;
4197 break;
4198 }
4199
4200 out:
4201 return ret;
4202 }
4203
4204 static int btrfs_uuid_rescan_kthread(void *data)
4205 {
4206 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
4207 int ret;
4208
4209 /*
4210 * 1st step is to iterate through the existing UUID tree and
4211 * to delete all entries that contain outdated data.
4212 * 2nd step is to add all missing entries to the UUID tree.
4213 */
4214 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
4215 if (ret < 0) {
4216 btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
4217 up(&fs_info->uuid_tree_rescan_sem);
4218 return ret;
4219 }
4220 return btrfs_uuid_scan_kthread(data);
4221 }
4222
4223 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
4224 {
4225 struct btrfs_trans_handle *trans;
4226 struct btrfs_root *tree_root = fs_info->tree_root;
4227 struct btrfs_root *uuid_root;
4228 struct task_struct *task;
4229 int ret;
4230
4231 /*
4232 * 1 - root node
4233 * 1 - root item
4234 */
4235 trans = btrfs_start_transaction(tree_root, 2);
4236 if (IS_ERR(trans))
4237 return PTR_ERR(trans);
4238
4239 uuid_root = btrfs_create_tree(trans, fs_info,
4240 BTRFS_UUID_TREE_OBJECTID);
4241 if (IS_ERR(uuid_root)) {
4242 ret = PTR_ERR(uuid_root);
4243 btrfs_abort_transaction(trans, tree_root, ret);
4244 btrfs_end_transaction(trans, tree_root);
4245 return ret;
4246 }
4247
4248 fs_info->uuid_root = uuid_root;
4249
4250 ret = btrfs_commit_transaction(trans, tree_root);
4251 if (ret)
4252 return ret;
4253
4254 down(&fs_info->uuid_tree_rescan_sem);
4255 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
4256 if (IS_ERR(task)) {
4257 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
4258 btrfs_warn(fs_info, "failed to start uuid_scan task");
4259 up(&fs_info->uuid_tree_rescan_sem);
4260 return PTR_ERR(task);
4261 }
4262
4263 return 0;
4264 }
4265
4266 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
4267 {
4268 struct task_struct *task;
4269
4270 down(&fs_info->uuid_tree_rescan_sem);
4271 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
4272 if (IS_ERR(task)) {
4273 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
4274 btrfs_warn(fs_info, "failed to start uuid_rescan task");
4275 up(&fs_info->uuid_tree_rescan_sem);
4276 return PTR_ERR(task);
4277 }
4278
4279 return 0;
4280 }
4281
4282 /*
4283 * shrinking a device means finding all of the device extents past
4284 * the new size, and then following the back refs to the chunks.
4285 * The chunk relocation code actually frees the device extent
4286 */
4287 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
4288 {
4289 struct btrfs_trans_handle *trans;
4290 struct btrfs_root *root = device->dev_root;
4291 struct btrfs_dev_extent *dev_extent = NULL;
4292 struct btrfs_path *path;
4293 u64 length;
4294 u64 chunk_offset;
4295 int ret;
4296 int slot;
4297 int failed = 0;
4298 bool retried = false;
4299 bool checked_pending_chunks = false;
4300 struct extent_buffer *l;
4301 struct btrfs_key key;
4302 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4303 u64 old_total = btrfs_super_total_bytes(super_copy);
4304 u64 old_size = btrfs_device_get_total_bytes(device);
4305 u64 diff = old_size - new_size;
4306
4307 if (device->is_tgtdev_for_dev_replace)
4308 return -EINVAL;
4309
4310 path = btrfs_alloc_path();
4311 if (!path)
4312 return -ENOMEM;
4313
4314 path->reada = READA_FORWARD;
4315
4316 lock_chunks(root);
4317
4318 btrfs_device_set_total_bytes(device, new_size);
4319 if (device->writeable) {
4320 device->fs_devices->total_rw_bytes -= diff;
4321 spin_lock(&root->fs_info->free_chunk_lock);
4322 root->fs_info->free_chunk_space -= diff;
4323 spin_unlock(&root->fs_info->free_chunk_lock);
4324 }
4325 unlock_chunks(root);
4326
4327 again:
4328 key.objectid = device->devid;
4329 key.offset = (u64)-1;
4330 key.type = BTRFS_DEV_EXTENT_KEY;
4331
4332 do {
4333 mutex_lock(&root->fs_info->delete_unused_bgs_mutex);
4334 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4335 if (ret < 0) {
4336 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4337 goto done;
4338 }
4339
4340 ret = btrfs_previous_item(root, path, 0, key.type);
4341 if (ret)
4342 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4343 if (ret < 0)
4344 goto done;
4345 if (ret) {
4346 ret = 0;
4347 btrfs_release_path(path);
4348 break;
4349 }
4350
4351 l = path->nodes[0];
4352 slot = path->slots[0];
4353 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
4354
4355 if (key.objectid != device->devid) {
4356 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4357 btrfs_release_path(path);
4358 break;
4359 }
4360
4361 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
4362 length = btrfs_dev_extent_length(l, dev_extent);
4363
4364 if (key.offset + length <= new_size) {
4365 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4366 btrfs_release_path(path);
4367 break;
4368 }
4369
4370 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
4371 btrfs_release_path(path);
4372
4373 ret = btrfs_relocate_chunk(root, chunk_offset);
4374 mutex_unlock(&root->fs_info->delete_unused_bgs_mutex);
4375 if (ret && ret != -ENOSPC)
4376 goto done;
4377 if (ret == -ENOSPC)
4378 failed++;
4379 } while (key.offset-- > 0);
4380
4381 if (failed && !retried) {
4382 failed = 0;
4383 retried = true;
4384 goto again;
4385 } else if (failed && retried) {
4386 ret = -ENOSPC;
4387 goto done;
4388 }
4389
4390 /* Shrinking succeeded, else we would be at "done". */
4391 trans = btrfs_start_transaction(root, 0);
4392 if (IS_ERR(trans)) {
4393 ret = PTR_ERR(trans);
4394 goto done;
4395 }
4396
4397 lock_chunks(root);
4398
4399 /*
4400 * We checked in the above loop all device extents that were already in
4401 * the device tree. However before we have updated the device's
4402 * total_bytes to the new size, we might have had chunk allocations that
4403 * have not complete yet (new block groups attached to transaction
4404 * handles), and therefore their device extents were not yet in the
4405 * device tree and we missed them in the loop above. So if we have any
4406 * pending chunk using a device extent that overlaps the device range
4407 * that we can not use anymore, commit the current transaction and
4408 * repeat the search on the device tree - this way we guarantee we will
4409 * not have chunks using device extents that end beyond 'new_size'.
4410 */
4411 if (!checked_pending_chunks) {
4412 u64 start = new_size;
4413 u64 len = old_size - new_size;
4414
4415 if (contains_pending_extent(trans->transaction, device,
4416 &start, len)) {
4417 unlock_chunks(root);
4418 checked_pending_chunks = true;
4419 failed = 0;
4420 retried = false;
4421 ret = btrfs_commit_transaction(trans, root);
4422 if (ret)
4423 goto done;
4424 goto again;
4425 }
4426 }
4427
4428 btrfs_device_set_disk_total_bytes(device, new_size);
4429 if (list_empty(&device->resized_list))
4430 list_add_tail(&device->resized_list,
4431 &root->fs_info->fs_devices->resized_devices);
4432
4433 WARN_ON(diff > old_total);
4434 btrfs_set_super_total_bytes(super_copy, old_total - diff);
4435 unlock_chunks(root);
4436
4437 /* Now btrfs_update_device() will change the on-disk size. */
4438 ret = btrfs_update_device(trans, device);
4439 btrfs_end_transaction(trans, root);
4440 done:
4441 btrfs_free_path(path);
4442 if (ret) {
4443 lock_chunks(root);
4444 btrfs_device_set_total_bytes(device, old_size);
4445 if (device->writeable)
4446 device->fs_devices->total_rw_bytes += diff;
4447 spin_lock(&root->fs_info->free_chunk_lock);
4448 root->fs_info->free_chunk_space += diff;
4449 spin_unlock(&root->fs_info->free_chunk_lock);
4450 unlock_chunks(root);
4451 }
4452 return ret;
4453 }
4454
4455 static int btrfs_add_system_chunk(struct btrfs_root *root,
4456 struct btrfs_key *key,
4457 struct btrfs_chunk *chunk, int item_size)
4458 {
4459 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4460 struct btrfs_disk_key disk_key;
4461 u32 array_size;
4462 u8 *ptr;
4463
4464 lock_chunks(root);
4465 array_size = btrfs_super_sys_array_size(super_copy);
4466 if (array_size + item_size + sizeof(disk_key)
4467 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE) {
4468 unlock_chunks(root);
4469 return -EFBIG;
4470 }
4471
4472 ptr = super_copy->sys_chunk_array + array_size;
4473 btrfs_cpu_key_to_disk(&disk_key, key);
4474 memcpy(ptr, &disk_key, sizeof(disk_key));
4475 ptr += sizeof(disk_key);
4476 memcpy(ptr, chunk, item_size);
4477 item_size += sizeof(disk_key);
4478 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
4479 unlock_chunks(root);
4480
4481 return 0;
4482 }
4483
4484 /*
4485 * sort the devices in descending order by max_avail, total_avail
4486 */
4487 static int btrfs_cmp_device_info(const void *a, const void *b)
4488 {
4489 const struct btrfs_device_info *di_a = a;
4490 const struct btrfs_device_info *di_b = b;
4491
4492 if (di_a->max_avail > di_b->max_avail)
4493 return -1;
4494 if (di_a->max_avail < di_b->max_avail)
4495 return 1;
4496 if (di_a->total_avail > di_b->total_avail)
4497 return -1;
4498 if (di_a->total_avail < di_b->total_avail)
4499 return 1;
4500 return 0;
4501 }
4502
4503 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
4504 {
4505 /* TODO allow them to set a preferred stripe size */
4506 return SZ_64K;
4507 }
4508
4509 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
4510 {
4511 if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
4512 return;
4513
4514 btrfs_set_fs_incompat(info, RAID56);
4515 }
4516
4517 #define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \
4518 - sizeof(struct btrfs_item) \
4519 - sizeof(struct btrfs_chunk)) \
4520 / sizeof(struct btrfs_stripe) + 1)
4521
4522 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
4523 - 2 * sizeof(struct btrfs_disk_key) \
4524 - 2 * sizeof(struct btrfs_chunk)) \
4525 / sizeof(struct btrfs_stripe) + 1)
4526
4527 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4528 struct btrfs_root *extent_root, u64 start,
4529 u64 type)
4530 {
4531 struct btrfs_fs_info *info = extent_root->fs_info;
4532 struct btrfs_fs_devices *fs_devices = info->fs_devices;
4533 struct list_head *cur;
4534 struct map_lookup *map = NULL;
4535 struct extent_map_tree *em_tree;
4536 struct extent_map *em;
4537 struct btrfs_device_info *devices_info = NULL;
4538 u64 total_avail;
4539 int num_stripes; /* total number of stripes to allocate */
4540 int data_stripes; /* number of stripes that count for
4541 block group size */
4542 int sub_stripes; /* sub_stripes info for map */
4543 int dev_stripes; /* stripes per dev */
4544 int devs_max; /* max devs to use */
4545 int devs_min; /* min devs needed */
4546 int devs_increment; /* ndevs has to be a multiple of this */
4547 int ncopies; /* how many copies to data has */
4548 int ret;
4549 u64 max_stripe_size;
4550 u64 max_chunk_size;
4551 u64 stripe_size;
4552 u64 num_bytes;
4553 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
4554 int ndevs;
4555 int i;
4556 int j;
4557 int index;
4558
4559 BUG_ON(!alloc_profile_is_valid(type, 0));
4560
4561 if (list_empty(&fs_devices->alloc_list))
4562 return -ENOSPC;
4563
4564 index = __get_raid_index(type);
4565
4566 sub_stripes = btrfs_raid_array[index].sub_stripes;
4567 dev_stripes = btrfs_raid_array[index].dev_stripes;
4568 devs_max = btrfs_raid_array[index].devs_max;
4569 devs_min = btrfs_raid_array[index].devs_min;
4570 devs_increment = btrfs_raid_array[index].devs_increment;
4571 ncopies = btrfs_raid_array[index].ncopies;
4572
4573 if (type & BTRFS_BLOCK_GROUP_DATA) {
4574 max_stripe_size = SZ_1G;
4575 max_chunk_size = 10 * max_stripe_size;
4576 if (!devs_max)
4577 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4578 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
4579 /* for larger filesystems, use larger metadata chunks */
4580 if (fs_devices->total_rw_bytes > 50ULL * SZ_1G)
4581 max_stripe_size = SZ_1G;
4582 else
4583 max_stripe_size = SZ_256M;
4584 max_chunk_size = max_stripe_size;
4585 if (!devs_max)
4586 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4587 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
4588 max_stripe_size = SZ_32M;
4589 max_chunk_size = 2 * max_stripe_size;
4590 if (!devs_max)
4591 devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
4592 } else {
4593 btrfs_err(info, "invalid chunk type 0x%llx requested",
4594 type);
4595 BUG_ON(1);
4596 }
4597
4598 /* we don't want a chunk larger than 10% of writeable space */
4599 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
4600 max_chunk_size);
4601
4602 devices_info = kcalloc(fs_devices->rw_devices, sizeof(*devices_info),
4603 GFP_NOFS);
4604 if (!devices_info)
4605 return -ENOMEM;
4606
4607 cur = fs_devices->alloc_list.next;
4608
4609 /*
4610 * in the first pass through the devices list, we gather information
4611 * about the available holes on each device.
4612 */
4613 ndevs = 0;
4614 while (cur != &fs_devices->alloc_list) {
4615 struct btrfs_device *device;
4616 u64 max_avail;
4617 u64 dev_offset;
4618
4619 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
4620
4621 cur = cur->next;
4622
4623 if (!device->writeable) {
4624 WARN(1, KERN_ERR
4625 "BTRFS: read-only device in alloc_list\n");
4626 continue;
4627 }
4628
4629 if (!device->in_fs_metadata ||
4630 device->is_tgtdev_for_dev_replace)
4631 continue;
4632
4633 if (device->total_bytes > device->bytes_used)
4634 total_avail = device->total_bytes - device->bytes_used;
4635 else
4636 total_avail = 0;
4637
4638 /* If there is no space on this device, skip it. */
4639 if (total_avail == 0)
4640 continue;
4641
4642 ret = find_free_dev_extent(trans, device,
4643 max_stripe_size * dev_stripes,
4644 &dev_offset, &max_avail);
4645 if (ret && ret != -ENOSPC)
4646 goto error;
4647
4648 if (ret == 0)
4649 max_avail = max_stripe_size * dev_stripes;
4650
4651 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
4652 continue;
4653
4654 if (ndevs == fs_devices->rw_devices) {
4655 WARN(1, "%s: found more than %llu devices\n",
4656 __func__, fs_devices->rw_devices);
4657 break;
4658 }
4659 devices_info[ndevs].dev_offset = dev_offset;
4660 devices_info[ndevs].max_avail = max_avail;
4661 devices_info[ndevs].total_avail = total_avail;
4662 devices_info[ndevs].dev = device;
4663 ++ndevs;
4664 }
4665
4666 /*
4667 * now sort the devices by hole size / available space
4668 */
4669 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
4670 btrfs_cmp_device_info, NULL);
4671
4672 /* round down to number of usable stripes */
4673 ndevs -= ndevs % devs_increment;
4674
4675 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
4676 ret = -ENOSPC;
4677 goto error;
4678 }
4679
4680 if (devs_max && ndevs > devs_max)
4681 ndevs = devs_max;
4682 /*
4683 * the primary goal is to maximize the number of stripes, so use as many
4684 * devices as possible, even if the stripes are not maximum sized.
4685 */
4686 stripe_size = devices_info[ndevs-1].max_avail;
4687 num_stripes = ndevs * dev_stripes;
4688
4689 /*
4690 * this will have to be fixed for RAID1 and RAID10 over
4691 * more drives
4692 */
4693 data_stripes = num_stripes / ncopies;
4694
4695 if (type & BTRFS_BLOCK_GROUP_RAID5) {
4696 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
4697 extent_root->stripesize);
4698 data_stripes = num_stripes - 1;
4699 }
4700 if (type & BTRFS_BLOCK_GROUP_RAID6) {
4701 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
4702 extent_root->stripesize);
4703 data_stripes = num_stripes - 2;
4704 }
4705
4706 /*
4707 * Use the number of data stripes to figure out how big this chunk
4708 * is really going to be in terms of logical address space,
4709 * and compare that answer with the max chunk size
4710 */
4711 if (stripe_size * data_stripes > max_chunk_size) {
4712 u64 mask = (1ULL << 24) - 1;
4713
4714 stripe_size = div_u64(max_chunk_size, data_stripes);
4715
4716 /* bump the answer up to a 16MB boundary */
4717 stripe_size = (stripe_size + mask) & ~mask;
4718
4719 /* but don't go higher than the limits we found
4720 * while searching for free extents
4721 */
4722 if (stripe_size > devices_info[ndevs-1].max_avail)
4723 stripe_size = devices_info[ndevs-1].max_avail;
4724 }
4725
4726 stripe_size = div_u64(stripe_size, dev_stripes);
4727
4728 /* align to BTRFS_STRIPE_LEN */
4729 stripe_size = div_u64(stripe_size, raid_stripe_len);
4730 stripe_size *= raid_stripe_len;
4731
4732 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4733 if (!map) {
4734 ret = -ENOMEM;
4735 goto error;
4736 }
4737 map->num_stripes = num_stripes;
4738
4739 for (i = 0; i < ndevs; ++i) {
4740 for (j = 0; j < dev_stripes; ++j) {
4741 int s = i * dev_stripes + j;
4742 map->stripes[s].dev = devices_info[i].dev;
4743 map->stripes[s].physical = devices_info[i].dev_offset +
4744 j * stripe_size;
4745 }
4746 }
4747 map->sector_size = extent_root->sectorsize;
4748 map->stripe_len = raid_stripe_len;
4749 map->io_align = raid_stripe_len;
4750 map->io_width = raid_stripe_len;
4751 map->type = type;
4752 map->sub_stripes = sub_stripes;
4753
4754 num_bytes = stripe_size * data_stripes;
4755
4756 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
4757
4758 em = alloc_extent_map();
4759 if (!em) {
4760 kfree(map);
4761 ret = -ENOMEM;
4762 goto error;
4763 }
4764 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
4765 em->map_lookup = map;
4766 em->start = start;
4767 em->len = num_bytes;
4768 em->block_start = 0;
4769 em->block_len = em->len;
4770 em->orig_block_len = stripe_size;
4771
4772 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4773 write_lock(&em_tree->lock);
4774 ret = add_extent_mapping(em_tree, em, 0);
4775 if (!ret) {
4776 list_add_tail(&em->list, &trans->transaction->pending_chunks);
4777 atomic_inc(&em->refs);
4778 }
4779 write_unlock(&em_tree->lock);
4780 if (ret) {
4781 free_extent_map(em);
4782 goto error;
4783 }
4784
4785 ret = btrfs_make_block_group(trans, extent_root, 0, type,
4786 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4787 start, num_bytes);
4788 if (ret)
4789 goto error_del_extent;
4790
4791 for (i = 0; i < map->num_stripes; i++) {
4792 num_bytes = map->stripes[i].dev->bytes_used + stripe_size;
4793 btrfs_device_set_bytes_used(map->stripes[i].dev, num_bytes);
4794 }
4795
4796 spin_lock(&extent_root->fs_info->free_chunk_lock);
4797 extent_root->fs_info->free_chunk_space -= (stripe_size *
4798 map->num_stripes);
4799 spin_unlock(&extent_root->fs_info->free_chunk_lock);
4800
4801 free_extent_map(em);
4802 check_raid56_incompat_flag(extent_root->fs_info, type);
4803
4804 kfree(devices_info);
4805 return 0;
4806
4807 error_del_extent:
4808 write_lock(&em_tree->lock);
4809 remove_extent_mapping(em_tree, em);
4810 write_unlock(&em_tree->lock);
4811
4812 /* One for our allocation */
4813 free_extent_map(em);
4814 /* One for the tree reference */
4815 free_extent_map(em);
4816 /* One for the pending_chunks list reference */
4817 free_extent_map(em);
4818 error:
4819 kfree(devices_info);
4820 return ret;
4821 }
4822
4823 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
4824 struct btrfs_root *extent_root,
4825 u64 chunk_offset, u64 chunk_size)
4826 {
4827 struct btrfs_key key;
4828 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
4829 struct btrfs_device *device;
4830 struct btrfs_chunk *chunk;
4831 struct btrfs_stripe *stripe;
4832 struct extent_map_tree *em_tree;
4833 struct extent_map *em;
4834 struct map_lookup *map;
4835 size_t item_size;
4836 u64 dev_offset;
4837 u64 stripe_size;
4838 int i = 0;
4839 int ret = 0;
4840
4841 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4842 read_lock(&em_tree->lock);
4843 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
4844 read_unlock(&em_tree->lock);
4845
4846 if (!em) {
4847 btrfs_crit(extent_root->fs_info, "unable to find logical "
4848 "%Lu len %Lu", chunk_offset, chunk_size);
4849 return -EINVAL;
4850 }
4851
4852 if (em->start != chunk_offset || em->len != chunk_size) {
4853 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted"
4854 " %Lu-%Lu, found %Lu-%Lu", chunk_offset,
4855 chunk_size, em->start, em->len);
4856 free_extent_map(em);
4857 return -EINVAL;
4858 }
4859
4860 map = em->map_lookup;
4861 item_size = btrfs_chunk_item_size(map->num_stripes);
4862 stripe_size = em->orig_block_len;
4863
4864 chunk = kzalloc(item_size, GFP_NOFS);
4865 if (!chunk) {
4866 ret = -ENOMEM;
4867 goto out;
4868 }
4869
4870 /*
4871 * Take the device list mutex to prevent races with the final phase of
4872 * a device replace operation that replaces the device object associated
4873 * with the map's stripes, because the device object's id can change
4874 * at any time during that final phase of the device replace operation
4875 * (dev-replace.c:btrfs_dev_replace_finishing()).
4876 */
4877 mutex_lock(&chunk_root->fs_info->fs_devices->device_list_mutex);
4878 for (i = 0; i < map->num_stripes; i++) {
4879 device = map->stripes[i].dev;
4880 dev_offset = map->stripes[i].physical;
4881
4882 ret = btrfs_update_device(trans, device);
4883 if (ret)
4884 break;
4885 ret = btrfs_alloc_dev_extent(trans, device,
4886 chunk_root->root_key.objectid,
4887 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4888 chunk_offset, dev_offset,
4889 stripe_size);
4890 if (ret)
4891 break;
4892 }
4893 if (ret) {
4894 mutex_unlock(&chunk_root->fs_info->fs_devices->device_list_mutex);
4895 goto out;
4896 }
4897
4898 stripe = &chunk->stripe;
4899 for (i = 0; i < map->num_stripes; i++) {
4900 device = map->stripes[i].dev;
4901 dev_offset = map->stripes[i].physical;
4902
4903 btrfs_set_stack_stripe_devid(stripe, device->devid);
4904 btrfs_set_stack_stripe_offset(stripe, dev_offset);
4905 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
4906 stripe++;
4907 }
4908 mutex_unlock(&chunk_root->fs_info->fs_devices->device_list_mutex);
4909
4910 btrfs_set_stack_chunk_length(chunk, chunk_size);
4911 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
4912 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
4913 btrfs_set_stack_chunk_type(chunk, map->type);
4914 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
4915 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
4916 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
4917 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
4918 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
4919
4920 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4921 key.type = BTRFS_CHUNK_ITEM_KEY;
4922 key.offset = chunk_offset;
4923
4924 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
4925 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
4926 /*
4927 * TODO: Cleanup of inserted chunk root in case of
4928 * failure.
4929 */
4930 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
4931 item_size);
4932 }
4933
4934 out:
4935 kfree(chunk);
4936 free_extent_map(em);
4937 return ret;
4938 }
4939
4940 /*
4941 * Chunk allocation falls into two parts. The first part does works
4942 * that make the new allocated chunk useable, but not do any operation
4943 * that modifies the chunk tree. The second part does the works that
4944 * require modifying the chunk tree. This division is important for the
4945 * bootstrap process of adding storage to a seed btrfs.
4946 */
4947 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4948 struct btrfs_root *extent_root, u64 type)
4949 {
4950 u64 chunk_offset;
4951
4952 ASSERT(mutex_is_locked(&extent_root->fs_info->chunk_mutex));
4953 chunk_offset = find_next_chunk(extent_root->fs_info);
4954 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type);
4955 }
4956
4957 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
4958 struct btrfs_root *root,
4959 struct btrfs_device *device)
4960 {
4961 u64 chunk_offset;
4962 u64 sys_chunk_offset;
4963 u64 alloc_profile;
4964 struct btrfs_fs_info *fs_info = root->fs_info;
4965 struct btrfs_root *extent_root = fs_info->extent_root;
4966 int ret;
4967
4968 chunk_offset = find_next_chunk(fs_info);
4969 alloc_profile = btrfs_get_alloc_profile(extent_root, 0);
4970 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset,
4971 alloc_profile);
4972 if (ret)
4973 return ret;
4974
4975 sys_chunk_offset = find_next_chunk(root->fs_info);
4976 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
4977 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset,
4978 alloc_profile);
4979 return ret;
4980 }
4981
4982 static inline int btrfs_chunk_max_errors(struct map_lookup *map)
4983 {
4984 int max_errors;
4985
4986 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
4987 BTRFS_BLOCK_GROUP_RAID10 |
4988 BTRFS_BLOCK_GROUP_RAID5 |
4989 BTRFS_BLOCK_GROUP_DUP)) {
4990 max_errors = 1;
4991 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
4992 max_errors = 2;
4993 } else {
4994 max_errors = 0;
4995 }
4996
4997 return max_errors;
4998 }
4999
5000 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
5001 {
5002 struct extent_map *em;
5003 struct map_lookup *map;
5004 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
5005 int readonly = 0;
5006 int miss_ndevs = 0;
5007 int i;
5008
5009 read_lock(&map_tree->map_tree.lock);
5010 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
5011 read_unlock(&map_tree->map_tree.lock);
5012 if (!em)
5013 return 1;
5014
5015 map = em->map_lookup;
5016 for (i = 0; i < map->num_stripes; i++) {
5017 if (map->stripes[i].dev->missing) {
5018 miss_ndevs++;
5019 continue;
5020 }
5021
5022 if (!map->stripes[i].dev->writeable) {
5023 readonly = 1;
5024 goto end;
5025 }
5026 }
5027
5028 /*
5029 * If the number of missing devices is larger than max errors,
5030 * we can not write the data into that chunk successfully, so
5031 * set it readonly.
5032 */
5033 if (miss_ndevs > btrfs_chunk_max_errors(map))
5034 readonly = 1;
5035 end:
5036 free_extent_map(em);
5037 return readonly;
5038 }
5039
5040 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
5041 {
5042 extent_map_tree_init(&tree->map_tree);
5043 }
5044
5045 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
5046 {
5047 struct extent_map *em;
5048
5049 while (1) {
5050 write_lock(&tree->map_tree.lock);
5051 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
5052 if (em)
5053 remove_extent_mapping(&tree->map_tree, em);
5054 write_unlock(&tree->map_tree.lock);
5055 if (!em)
5056 break;
5057 /* once for us */
5058 free_extent_map(em);
5059 /* once for the tree */
5060 free_extent_map(em);
5061 }
5062 }
5063
5064 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
5065 {
5066 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
5067 struct extent_map *em;
5068 struct map_lookup *map;
5069 struct extent_map_tree *em_tree = &map_tree->map_tree;
5070 int ret;
5071
5072 read_lock(&em_tree->lock);
5073 em = lookup_extent_mapping(em_tree, logical, len);
5074 read_unlock(&em_tree->lock);
5075
5076 /*
5077 * We could return errors for these cases, but that could get ugly and
5078 * we'd probably do the same thing which is just not do anything else
5079 * and exit, so return 1 so the callers don't try to use other copies.
5080 */
5081 if (!em) {
5082 btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
5083 logical+len);
5084 return 1;
5085 }
5086
5087 if (em->start > logical || em->start + em->len < logical) {
5088 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got "
5089 "%Lu-%Lu", logical, logical+len, em->start,
5090 em->start + em->len);
5091 free_extent_map(em);
5092 return 1;
5093 }
5094
5095 map = em->map_lookup;
5096 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
5097 ret = map->num_stripes;
5098 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5099 ret = map->sub_stripes;
5100 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
5101 ret = 2;
5102 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5103 ret = 3;
5104 else
5105 ret = 1;
5106 free_extent_map(em);
5107
5108 btrfs_dev_replace_lock(&fs_info->dev_replace, 0);
5109 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
5110 ret++;
5111 btrfs_dev_replace_unlock(&fs_info->dev_replace, 0);
5112
5113 return ret;
5114 }
5115
5116 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
5117 struct btrfs_mapping_tree *map_tree,
5118 u64 logical)
5119 {
5120 struct extent_map *em;
5121 struct map_lookup *map;
5122 struct extent_map_tree *em_tree = &map_tree->map_tree;
5123 unsigned long len = root->sectorsize;
5124
5125 read_lock(&em_tree->lock);
5126 em = lookup_extent_mapping(em_tree, logical, len);
5127 read_unlock(&em_tree->lock);
5128 BUG_ON(!em);
5129
5130 BUG_ON(em->start > logical || em->start + em->len < logical);
5131 map = em->map_lookup;
5132 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
5133 len = map->stripe_len * nr_data_stripes(map);
5134 free_extent_map(em);
5135 return len;
5136 }
5137
5138 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
5139 u64 logical, u64 len, int mirror_num)
5140 {
5141 struct extent_map *em;
5142 struct map_lookup *map;
5143 struct extent_map_tree *em_tree = &map_tree->map_tree;
5144 int ret = 0;
5145
5146 read_lock(&em_tree->lock);
5147 em = lookup_extent_mapping(em_tree, logical, len);
5148 read_unlock(&em_tree->lock);
5149 BUG_ON(!em);
5150
5151 BUG_ON(em->start > logical || em->start + em->len < logical);
5152 map = em->map_lookup;
5153 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
5154 ret = 1;
5155 free_extent_map(em);
5156 return ret;
5157 }
5158
5159 static int find_live_mirror(struct btrfs_fs_info *fs_info,
5160 struct map_lookup *map, int first, int num,
5161 int optimal, int dev_replace_is_ongoing)
5162 {
5163 int i;
5164 int tolerance;
5165 struct btrfs_device *srcdev;
5166
5167 if (dev_replace_is_ongoing &&
5168 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
5169 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
5170 srcdev = fs_info->dev_replace.srcdev;
5171 else
5172 srcdev = NULL;
5173
5174 /*
5175 * try to avoid the drive that is the source drive for a
5176 * dev-replace procedure, only choose it if no other non-missing
5177 * mirror is available
5178 */
5179 for (tolerance = 0; tolerance < 2; tolerance++) {
5180 if (map->stripes[optimal].dev->bdev &&
5181 (tolerance || map->stripes[optimal].dev != srcdev))
5182 return optimal;
5183 for (i = first; i < first + num; i++) {
5184 if (map->stripes[i].dev->bdev &&
5185 (tolerance || map->stripes[i].dev != srcdev))
5186 return i;
5187 }
5188 }
5189
5190 /* we couldn't find one that doesn't fail. Just return something
5191 * and the io error handling code will clean up eventually
5192 */
5193 return optimal;
5194 }
5195
5196 static inline int parity_smaller(u64 a, u64 b)
5197 {
5198 return a > b;
5199 }
5200
5201 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
5202 static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes)
5203 {
5204 struct btrfs_bio_stripe s;
5205 int i;
5206 u64 l;
5207 int again = 1;
5208
5209 while (again) {
5210 again = 0;
5211 for (i = 0; i < num_stripes - 1; i++) {
5212 if (parity_smaller(bbio->raid_map[i],
5213 bbio->raid_map[i+1])) {
5214 s = bbio->stripes[i];
5215 l = bbio->raid_map[i];
5216 bbio->stripes[i] = bbio->stripes[i+1];
5217 bbio->raid_map[i] = bbio->raid_map[i+1];
5218 bbio->stripes[i+1] = s;
5219 bbio->raid_map[i+1] = l;
5220
5221 again = 1;
5222 }
5223 }
5224 }
5225 }
5226
5227 static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
5228 {
5229 struct btrfs_bio *bbio = kzalloc(
5230 /* the size of the btrfs_bio */
5231 sizeof(struct btrfs_bio) +
5232 /* plus the variable array for the stripes */
5233 sizeof(struct btrfs_bio_stripe) * (total_stripes) +
5234 /* plus the variable array for the tgt dev */
5235 sizeof(int) * (real_stripes) +
5236 /*
5237 * plus the raid_map, which includes both the tgt dev
5238 * and the stripes
5239 */
5240 sizeof(u64) * (total_stripes),
5241 GFP_NOFS|__GFP_NOFAIL);
5242
5243 atomic_set(&bbio->error, 0);
5244 atomic_set(&bbio->refs, 1);
5245
5246 return bbio;
5247 }
5248
5249 void btrfs_get_bbio(struct btrfs_bio *bbio)
5250 {
5251 WARN_ON(!atomic_read(&bbio->refs));
5252 atomic_inc(&bbio->refs);
5253 }
5254
5255 void btrfs_put_bbio(struct btrfs_bio *bbio)
5256 {
5257 if (!bbio)
5258 return;
5259 if (atomic_dec_and_test(&bbio->refs))
5260 kfree(bbio);
5261 }
5262
5263 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5264 u64 logical, u64 *length,
5265 struct btrfs_bio **bbio_ret,
5266 int mirror_num, int need_raid_map)
5267 {
5268 struct extent_map *em;
5269 struct map_lookup *map;
5270 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
5271 struct extent_map_tree *em_tree = &map_tree->map_tree;
5272 u64 offset;
5273 u64 stripe_offset;
5274 u64 stripe_end_offset;
5275 u64 stripe_nr;
5276 u64 stripe_nr_orig;
5277 u64 stripe_nr_end;
5278 u64 stripe_len;
5279 u32 stripe_index;
5280 int i;
5281 int ret = 0;
5282 int num_stripes;
5283 int max_errors = 0;
5284 int tgtdev_indexes = 0;
5285 struct btrfs_bio *bbio = NULL;
5286 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
5287 int dev_replace_is_ongoing = 0;
5288 int num_alloc_stripes;
5289 int patch_the_first_stripe_for_dev_replace = 0;
5290 u64 physical_to_patch_in_first_stripe = 0;
5291 u64 raid56_full_stripe_start = (u64)-1;
5292
5293 read_lock(&em_tree->lock);
5294 em = lookup_extent_mapping(em_tree, logical, *length);
5295 read_unlock(&em_tree->lock);
5296
5297 if (!em) {
5298 btrfs_crit(fs_info, "unable to find logical %llu len %llu",
5299 logical, *length);
5300 return -EINVAL;
5301 }
5302
5303 if (em->start > logical || em->start + em->len < logical) {
5304 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, "
5305 "found %Lu-%Lu", logical, em->start,
5306 em->start + em->len);
5307 free_extent_map(em);
5308 return -EINVAL;
5309 }
5310
5311 map = em->map_lookup;
5312 offset = logical - em->start;
5313
5314 stripe_len = map->stripe_len;
5315 stripe_nr = offset;
5316 /*
5317 * stripe_nr counts the total number of stripes we have to stride
5318 * to get to this block
5319 */
5320 stripe_nr = div64_u64(stripe_nr, stripe_len);
5321
5322 stripe_offset = stripe_nr * stripe_len;
5323 if (offset < stripe_offset) {
5324 btrfs_crit(fs_info, "stripe math has gone wrong, "
5325 "stripe_offset=%llu, offset=%llu, start=%llu, "
5326 "logical=%llu, stripe_len=%llu",
5327 stripe_offset, offset, em->start, logical,
5328 stripe_len);
5329 free_extent_map(em);
5330 return -EINVAL;
5331 }
5332
5333 /* stripe_offset is the offset of this block in its stripe*/
5334 stripe_offset = offset - stripe_offset;
5335
5336 /* if we're here for raid56, we need to know the stripe aligned start */
5337 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5338 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
5339 raid56_full_stripe_start = offset;
5340
5341 /* allow a write of a full stripe, but make sure we don't
5342 * allow straddling of stripes
5343 */
5344 raid56_full_stripe_start = div64_u64(raid56_full_stripe_start,
5345 full_stripe_len);
5346 raid56_full_stripe_start *= full_stripe_len;
5347 }
5348
5349 if (rw & REQ_DISCARD) {
5350 /* we don't discard raid56 yet */
5351 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5352 ret = -EOPNOTSUPP;
5353 goto out;
5354 }
5355 *length = min_t(u64, em->len - offset, *length);
5356 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
5357 u64 max_len;
5358 /* For writes to RAID[56], allow a full stripeset across all disks.
5359 For other RAID types and for RAID[56] reads, just allow a single
5360 stripe (on a single disk). */
5361 if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
5362 (rw & REQ_WRITE)) {
5363 max_len = stripe_len * nr_data_stripes(map) -
5364 (offset - raid56_full_stripe_start);
5365 } else {
5366 /* we limit the length of each bio to what fits in a stripe */
5367 max_len = stripe_len - stripe_offset;
5368 }
5369 *length = min_t(u64, em->len - offset, max_len);
5370 } else {
5371 *length = em->len - offset;
5372 }
5373
5374 /* This is for when we're called from btrfs_merge_bio_hook() and all
5375 it cares about is the length */
5376 if (!bbio_ret)
5377 goto out;
5378
5379 btrfs_dev_replace_lock(dev_replace, 0);
5380 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
5381 if (!dev_replace_is_ongoing)
5382 btrfs_dev_replace_unlock(dev_replace, 0);
5383 else
5384 btrfs_dev_replace_set_lock_blocking(dev_replace);
5385
5386 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
5387 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
5388 dev_replace->tgtdev != NULL) {
5389 /*
5390 * in dev-replace case, for repair case (that's the only
5391 * case where the mirror is selected explicitly when
5392 * calling btrfs_map_block), blocks left of the left cursor
5393 * can also be read from the target drive.
5394 * For REQ_GET_READ_MIRRORS, the target drive is added as
5395 * the last one to the array of stripes. For READ, it also
5396 * needs to be supported using the same mirror number.
5397 * If the requested block is not left of the left cursor,
5398 * EIO is returned. This can happen because btrfs_num_copies()
5399 * returns one more in the dev-replace case.
5400 */
5401 u64 tmp_length = *length;
5402 struct btrfs_bio *tmp_bbio = NULL;
5403 int tmp_num_stripes;
5404 u64 srcdev_devid = dev_replace->srcdev->devid;
5405 int index_srcdev = 0;
5406 int found = 0;
5407 u64 physical_of_found = 0;
5408
5409 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
5410 logical, &tmp_length, &tmp_bbio, 0, 0);
5411 if (ret) {
5412 WARN_ON(tmp_bbio != NULL);
5413 goto out;
5414 }
5415
5416 tmp_num_stripes = tmp_bbio->num_stripes;
5417 if (mirror_num > tmp_num_stripes) {
5418 /*
5419 * REQ_GET_READ_MIRRORS does not contain this
5420 * mirror, that means that the requested area
5421 * is not left of the left cursor
5422 */
5423 ret = -EIO;
5424 btrfs_put_bbio(tmp_bbio);
5425 goto out;
5426 }
5427
5428 /*
5429 * process the rest of the function using the mirror_num
5430 * of the source drive. Therefore look it up first.
5431 * At the end, patch the device pointer to the one of the
5432 * target drive.
5433 */
5434 for (i = 0; i < tmp_num_stripes; i++) {
5435 if (tmp_bbio->stripes[i].dev->devid != srcdev_devid)
5436 continue;
5437
5438 /*
5439 * In case of DUP, in order to keep it simple, only add
5440 * the mirror with the lowest physical address
5441 */
5442 if (found &&
5443 physical_of_found <= tmp_bbio->stripes[i].physical)
5444 continue;
5445
5446 index_srcdev = i;
5447 found = 1;
5448 physical_of_found = tmp_bbio->stripes[i].physical;
5449 }
5450
5451 btrfs_put_bbio(tmp_bbio);
5452
5453 if (!found) {
5454 WARN_ON(1);
5455 ret = -EIO;
5456 goto out;
5457 }
5458
5459 mirror_num = index_srcdev + 1;
5460 patch_the_first_stripe_for_dev_replace = 1;
5461 physical_to_patch_in_first_stripe = physical_of_found;
5462 } else if (mirror_num > map->num_stripes) {
5463 mirror_num = 0;
5464 }
5465
5466 num_stripes = 1;
5467 stripe_index = 0;
5468 stripe_nr_orig = stripe_nr;
5469 stripe_nr_end = ALIGN(offset + *length, map->stripe_len);
5470 stripe_nr_end = div_u64(stripe_nr_end, map->stripe_len);
5471 stripe_end_offset = stripe_nr_end * map->stripe_len -
5472 (offset + *length);
5473
5474 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5475 if (rw & REQ_DISCARD)
5476 num_stripes = min_t(u64, map->num_stripes,
5477 stripe_nr_end - stripe_nr_orig);
5478 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5479 &stripe_index);
5480 if (!(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)))
5481 mirror_num = 1;
5482 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
5483 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
5484 num_stripes = map->num_stripes;
5485 else if (mirror_num)
5486 stripe_index = mirror_num - 1;
5487 else {
5488 stripe_index = find_live_mirror(fs_info, map, 0,
5489 map->num_stripes,
5490 current->pid % map->num_stripes,
5491 dev_replace_is_ongoing);
5492 mirror_num = stripe_index + 1;
5493 }
5494
5495 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
5496 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
5497 num_stripes = map->num_stripes;
5498 } else if (mirror_num) {
5499 stripe_index = mirror_num - 1;
5500 } else {
5501 mirror_num = 1;
5502 }
5503
5504 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5505 u32 factor = map->num_stripes / map->sub_stripes;
5506
5507 stripe_nr = div_u64_rem(stripe_nr, factor, &stripe_index);
5508 stripe_index *= map->sub_stripes;
5509
5510 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5511 num_stripes = map->sub_stripes;
5512 else if (rw & REQ_DISCARD)
5513 num_stripes = min_t(u64, map->sub_stripes *
5514 (stripe_nr_end - stripe_nr_orig),
5515 map->num_stripes);
5516 else if (mirror_num)
5517 stripe_index += mirror_num - 1;
5518 else {
5519 int old_stripe_index = stripe_index;
5520 stripe_index = find_live_mirror(fs_info, map,
5521 stripe_index,
5522 map->sub_stripes, stripe_index +
5523 current->pid % map->sub_stripes,
5524 dev_replace_is_ongoing);
5525 mirror_num = stripe_index - old_stripe_index + 1;
5526 }
5527
5528 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5529 if (need_raid_map &&
5530 ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5531 mirror_num > 1)) {
5532 /* push stripe_nr back to the start of the full stripe */
5533 stripe_nr = div_u64(raid56_full_stripe_start,
5534 stripe_len * nr_data_stripes(map));
5535
5536 /* RAID[56] write or recovery. Return all stripes */
5537 num_stripes = map->num_stripes;
5538 max_errors = nr_parity_stripes(map);
5539
5540 *length = map->stripe_len;
5541 stripe_index = 0;
5542 stripe_offset = 0;
5543 } else {
5544 /*
5545 * Mirror #0 or #1 means the original data block.
5546 * Mirror #2 is RAID5 parity block.
5547 * Mirror #3 is RAID6 Q block.
5548 */
5549 stripe_nr = div_u64_rem(stripe_nr,
5550 nr_data_stripes(map), &stripe_index);
5551 if (mirror_num > 1)
5552 stripe_index = nr_data_stripes(map) +
5553 mirror_num - 2;
5554
5555 /* We distribute the parity blocks across stripes */
5556 div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
5557 &stripe_index);
5558 if (!(rw & (REQ_WRITE | REQ_DISCARD |
5559 REQ_GET_READ_MIRRORS)) && mirror_num <= 1)
5560 mirror_num = 1;
5561 }
5562 } else {
5563 /*
5564 * after this, stripe_nr is the number of stripes on this
5565 * device we have to walk to find the data, and stripe_index is
5566 * the number of our device in the stripe array
5567 */
5568 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes,
5569 &stripe_index);
5570 mirror_num = stripe_index + 1;
5571 }
5572 if (stripe_index >= map->num_stripes) {
5573 btrfs_crit(fs_info, "stripe index math went horribly wrong, "
5574 "got stripe_index=%u, num_stripes=%u",
5575 stripe_index, map->num_stripes);
5576 ret = -EINVAL;
5577 goto out;
5578 }
5579
5580 num_alloc_stripes = num_stripes;
5581 if (dev_replace_is_ongoing) {
5582 if (rw & (REQ_WRITE | REQ_DISCARD))
5583 num_alloc_stripes <<= 1;
5584 if (rw & REQ_GET_READ_MIRRORS)
5585 num_alloc_stripes++;
5586 tgtdev_indexes = num_stripes;
5587 }
5588
5589 bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes);
5590 if (!bbio) {
5591 ret = -ENOMEM;
5592 goto out;
5593 }
5594 if (dev_replace_is_ongoing)
5595 bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes);
5596
5597 /* build raid_map */
5598 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
5599 need_raid_map && ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
5600 mirror_num > 1)) {
5601 u64 tmp;
5602 unsigned rot;
5603
5604 bbio->raid_map = (u64 *)((void *)bbio->stripes +
5605 sizeof(struct btrfs_bio_stripe) *
5606 num_alloc_stripes +
5607 sizeof(int) * tgtdev_indexes);
5608
5609 /* Work out the disk rotation on this stripe-set */
5610 div_u64_rem(stripe_nr, num_stripes, &rot);
5611
5612 /* Fill in the logical address of each stripe */
5613 tmp = stripe_nr * nr_data_stripes(map);
5614 for (i = 0; i < nr_data_stripes(map); i++)
5615 bbio->raid_map[(i+rot) % num_stripes] =
5616 em->start + (tmp + i) * map->stripe_len;
5617
5618 bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
5619 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5620 bbio->raid_map[(i+rot+1) % num_stripes] =
5621 RAID6_Q_STRIPE;
5622 }
5623
5624 if (rw & REQ_DISCARD) {
5625 u32 factor = 0;
5626 u32 sub_stripes = 0;
5627 u64 stripes_per_dev = 0;
5628 u32 remaining_stripes = 0;
5629 u32 last_stripe = 0;
5630
5631 if (map->type &
5632 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
5633 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5634 sub_stripes = 1;
5635 else
5636 sub_stripes = map->sub_stripes;
5637
5638 factor = map->num_stripes / sub_stripes;
5639 stripes_per_dev = div_u64_rem(stripe_nr_end -
5640 stripe_nr_orig,
5641 factor,
5642 &remaining_stripes);
5643 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
5644 last_stripe *= sub_stripes;
5645 }
5646
5647 for (i = 0; i < num_stripes; i++) {
5648 bbio->stripes[i].physical =
5649 map->stripes[stripe_index].physical +
5650 stripe_offset + stripe_nr * map->stripe_len;
5651 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
5652
5653 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
5654 BTRFS_BLOCK_GROUP_RAID10)) {
5655 bbio->stripes[i].length = stripes_per_dev *
5656 map->stripe_len;
5657
5658 if (i / sub_stripes < remaining_stripes)
5659 bbio->stripes[i].length +=
5660 map->stripe_len;
5661
5662 /*
5663 * Special for the first stripe and
5664 * the last stripe:
5665 *
5666 * |-------|...|-------|
5667 * |----------|
5668 * off end_off
5669 */
5670 if (i < sub_stripes)
5671 bbio->stripes[i].length -=
5672 stripe_offset;
5673
5674 if (stripe_index >= last_stripe &&
5675 stripe_index <= (last_stripe +
5676 sub_stripes - 1))
5677 bbio->stripes[i].length -=
5678 stripe_end_offset;
5679
5680 if (i == sub_stripes - 1)
5681 stripe_offset = 0;
5682 } else
5683 bbio->stripes[i].length = *length;
5684
5685 stripe_index++;
5686 if (stripe_index == map->num_stripes) {
5687 /* This could only happen for RAID0/10 */
5688 stripe_index = 0;
5689 stripe_nr++;
5690 }
5691 }
5692 } else {
5693 for (i = 0; i < num_stripes; i++) {
5694 bbio->stripes[i].physical =
5695 map->stripes[stripe_index].physical +
5696 stripe_offset +
5697 stripe_nr * map->stripe_len;
5698 bbio->stripes[i].dev =
5699 map->stripes[stripe_index].dev;
5700 stripe_index++;
5701 }
5702 }
5703
5704 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
5705 max_errors = btrfs_chunk_max_errors(map);
5706
5707 if (bbio->raid_map)
5708 sort_parity_stripes(bbio, num_stripes);
5709
5710 tgtdev_indexes = 0;
5711 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
5712 dev_replace->tgtdev != NULL) {
5713 int index_where_to_add;
5714 u64 srcdev_devid = dev_replace->srcdev->devid;
5715
5716 /*
5717 * duplicate the write operations while the dev replace
5718 * procedure is running. Since the copying of the old disk
5719 * to the new disk takes place at run time while the
5720 * filesystem is mounted writable, the regular write
5721 * operations to the old disk have to be duplicated to go
5722 * to the new disk as well.
5723 * Note that device->missing is handled by the caller, and
5724 * that the write to the old disk is already set up in the
5725 * stripes array.
5726 */
5727 index_where_to_add = num_stripes;
5728 for (i = 0; i < num_stripes; i++) {
5729 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5730 /* write to new disk, too */
5731 struct btrfs_bio_stripe *new =
5732 bbio->stripes + index_where_to_add;
5733 struct btrfs_bio_stripe *old =
5734 bbio->stripes + i;
5735
5736 new->physical = old->physical;
5737 new->length = old->length;
5738 new->dev = dev_replace->tgtdev;
5739 bbio->tgtdev_map[i] = index_where_to_add;
5740 index_where_to_add++;
5741 max_errors++;
5742 tgtdev_indexes++;
5743 }
5744 }
5745 num_stripes = index_where_to_add;
5746 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
5747 dev_replace->tgtdev != NULL) {
5748 u64 srcdev_devid = dev_replace->srcdev->devid;
5749 int index_srcdev = 0;
5750 int found = 0;
5751 u64 physical_of_found = 0;
5752
5753 /*
5754 * During the dev-replace procedure, the target drive can
5755 * also be used to read data in case it is needed to repair
5756 * a corrupt block elsewhere. This is possible if the
5757 * requested area is left of the left cursor. In this area,
5758 * the target drive is a full copy of the source drive.
5759 */
5760 for (i = 0; i < num_stripes; i++) {
5761 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5762 /*
5763 * In case of DUP, in order to keep it
5764 * simple, only add the mirror with the
5765 * lowest physical address
5766 */
5767 if (found &&
5768 physical_of_found <=
5769 bbio->stripes[i].physical)
5770 continue;
5771 index_srcdev = i;
5772 found = 1;
5773 physical_of_found = bbio->stripes[i].physical;
5774 }
5775 }
5776 if (found) {
5777 struct btrfs_bio_stripe *tgtdev_stripe =
5778 bbio->stripes + num_stripes;
5779
5780 tgtdev_stripe->physical = physical_of_found;
5781 tgtdev_stripe->length =
5782 bbio->stripes[index_srcdev].length;
5783 tgtdev_stripe->dev = dev_replace->tgtdev;
5784 bbio->tgtdev_map[index_srcdev] = num_stripes;
5785
5786 tgtdev_indexes++;
5787 num_stripes++;
5788 }
5789 }
5790
5791 *bbio_ret = bbio;
5792 bbio->map_type = map->type;
5793 bbio->num_stripes = num_stripes;
5794 bbio->max_errors = max_errors;
5795 bbio->mirror_num = mirror_num;
5796 bbio->num_tgtdevs = tgtdev_indexes;
5797
5798 /*
5799 * this is the case that REQ_READ && dev_replace_is_ongoing &&
5800 * mirror_num == num_stripes + 1 && dev_replace target drive is
5801 * available as a mirror
5802 */
5803 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
5804 WARN_ON(num_stripes > 1);
5805 bbio->stripes[0].dev = dev_replace->tgtdev;
5806 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
5807 bbio->mirror_num = map->num_stripes + 1;
5808 }
5809 out:
5810 if (dev_replace_is_ongoing) {
5811 btrfs_dev_replace_clear_lock_blocking(dev_replace);
5812 btrfs_dev_replace_unlock(dev_replace, 0);
5813 }
5814 free_extent_map(em);
5815 return ret;
5816 }
5817
5818 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5819 u64 logical, u64 *length,
5820 struct btrfs_bio **bbio_ret, int mirror_num)
5821 {
5822 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5823 mirror_num, 0);
5824 }
5825
5826 /* For Scrub/replace */
5827 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
5828 u64 logical, u64 *length,
5829 struct btrfs_bio **bbio_ret, int mirror_num,
5830 int need_raid_map)
5831 {
5832 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5833 mirror_num, need_raid_map);
5834 }
5835
5836 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
5837 u64 chunk_start, u64 physical, u64 devid,
5838 u64 **logical, int *naddrs, int *stripe_len)
5839 {
5840 struct extent_map_tree *em_tree = &map_tree->map_tree;
5841 struct extent_map *em;
5842 struct map_lookup *map;
5843 u64 *buf;
5844 u64 bytenr;
5845 u64 length;
5846 u64 stripe_nr;
5847 u64 rmap_len;
5848 int i, j, nr = 0;
5849
5850 read_lock(&em_tree->lock);
5851 em = lookup_extent_mapping(em_tree, chunk_start, 1);
5852 read_unlock(&em_tree->lock);
5853
5854 if (!em) {
5855 printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
5856 chunk_start);
5857 return -EIO;
5858 }
5859
5860 if (em->start != chunk_start) {
5861 printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
5862 em->start, chunk_start);
5863 free_extent_map(em);
5864 return -EIO;
5865 }
5866 map = em->map_lookup;
5867
5868 length = em->len;
5869 rmap_len = map->stripe_len;
5870
5871 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5872 length = div_u64(length, map->num_stripes / map->sub_stripes);
5873 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5874 length = div_u64(length, map->num_stripes);
5875 else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
5876 length = div_u64(length, nr_data_stripes(map));
5877 rmap_len = map->stripe_len * nr_data_stripes(map);
5878 }
5879
5880 buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
5881 BUG_ON(!buf); /* -ENOMEM */
5882
5883 for (i = 0; i < map->num_stripes; i++) {
5884 if (devid && map->stripes[i].dev->devid != devid)
5885 continue;
5886 if (map->stripes[i].physical > physical ||
5887 map->stripes[i].physical + length <= physical)
5888 continue;
5889
5890 stripe_nr = physical - map->stripes[i].physical;
5891 stripe_nr = div_u64(stripe_nr, map->stripe_len);
5892
5893 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5894 stripe_nr = stripe_nr * map->num_stripes + i;
5895 stripe_nr = div_u64(stripe_nr, map->sub_stripes);
5896 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5897 stripe_nr = stripe_nr * map->num_stripes + i;
5898 } /* else if RAID[56], multiply by nr_data_stripes().
5899 * Alternatively, just use rmap_len below instead of
5900 * map->stripe_len */
5901
5902 bytenr = chunk_start + stripe_nr * rmap_len;
5903 WARN_ON(nr >= map->num_stripes);
5904 for (j = 0; j < nr; j++) {
5905 if (buf[j] == bytenr)
5906 break;
5907 }
5908 if (j == nr) {
5909 WARN_ON(nr >= map->num_stripes);
5910 buf[nr++] = bytenr;
5911 }
5912 }
5913
5914 *logical = buf;
5915 *naddrs = nr;
5916 *stripe_len = rmap_len;
5917
5918 free_extent_map(em);
5919 return 0;
5920 }
5921
5922 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio)
5923 {
5924 bio->bi_private = bbio->private;
5925 bio->bi_end_io = bbio->end_io;
5926 bio_endio(bio);
5927
5928 btrfs_put_bbio(bbio);
5929 }
5930
5931 static void btrfs_end_bio(struct bio *bio)
5932 {
5933 struct btrfs_bio *bbio = bio->bi_private;
5934 int is_orig_bio = 0;
5935
5936 if (bio->bi_error) {
5937 atomic_inc(&bbio->error);
5938 if (bio->bi_error == -EIO || bio->bi_error == -EREMOTEIO) {
5939 unsigned int stripe_index =
5940 btrfs_io_bio(bio)->stripe_index;
5941 struct btrfs_device *dev;
5942
5943 BUG_ON(stripe_index >= bbio->num_stripes);
5944 dev = bbio->stripes[stripe_index].dev;
5945 if (dev->bdev) {
5946 if (bio->bi_rw & WRITE)
5947 btrfs_dev_stat_inc(dev,
5948 BTRFS_DEV_STAT_WRITE_ERRS);
5949 else
5950 btrfs_dev_stat_inc(dev,
5951 BTRFS_DEV_STAT_READ_ERRS);
5952 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
5953 btrfs_dev_stat_inc(dev,
5954 BTRFS_DEV_STAT_FLUSH_ERRS);
5955 btrfs_dev_stat_print_on_error(dev);
5956 }
5957 }
5958 }
5959
5960 if (bio == bbio->orig_bio)
5961 is_orig_bio = 1;
5962
5963 btrfs_bio_counter_dec(bbio->fs_info);
5964
5965 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5966 if (!is_orig_bio) {
5967 bio_put(bio);
5968 bio = bbio->orig_bio;
5969 }
5970
5971 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5972 /* only send an error to the higher layers if it is
5973 * beyond the tolerance of the btrfs bio
5974 */
5975 if (atomic_read(&bbio->error) > bbio->max_errors) {
5976 bio->bi_error = -EIO;
5977 } else {
5978 /*
5979 * this bio is actually up to date, we didn't
5980 * go over the max number of errors
5981 */
5982 bio->bi_error = 0;
5983 }
5984
5985 btrfs_end_bbio(bbio, bio);
5986 } else if (!is_orig_bio) {
5987 bio_put(bio);
5988 }
5989 }
5990
5991 /*
5992 * see run_scheduled_bios for a description of why bios are collected for
5993 * async submit.
5994 *
5995 * This will add one bio to the pending list for a device and make sure
5996 * the work struct is scheduled.
5997 */
5998 static noinline void btrfs_schedule_bio(struct btrfs_root *root,
5999 struct btrfs_device *device,
6000 int rw, struct bio *bio)
6001 {
6002 int should_queue = 1;
6003 struct btrfs_pending_bios *pending_bios;
6004
6005 if (device->missing || !device->bdev) {
6006 bio_io_error(bio);
6007 return;
6008 }
6009
6010 /* don't bother with additional async steps for reads, right now */
6011 if (!(rw & REQ_WRITE)) {
6012 bio_get(bio);
6013 btrfsic_submit_bio(rw, bio);
6014 bio_put(bio);
6015 return;
6016 }
6017
6018 /*
6019 * nr_async_bios allows us to reliably return congestion to the
6020 * higher layers. Otherwise, the async bio makes it appear we have
6021 * made progress against dirty pages when we've really just put it
6022 * on a queue for later
6023 */
6024 atomic_inc(&root->fs_info->nr_async_bios);
6025 WARN_ON(bio->bi_next);
6026 bio->bi_next = NULL;
6027 bio->bi_rw |= rw;
6028
6029 spin_lock(&device->io_lock);
6030 if (bio->bi_rw & REQ_SYNC)
6031 pending_bios = &device->pending_sync_bios;
6032 else
6033 pending_bios = &device->pending_bios;
6034
6035 if (pending_bios->tail)
6036 pending_bios->tail->bi_next = bio;
6037
6038 pending_bios->tail = bio;
6039 if (!pending_bios->head)
6040 pending_bios->head = bio;
6041 if (device->running_pending)
6042 should_queue = 0;
6043
6044 spin_unlock(&device->io_lock);
6045
6046 if (should_queue)
6047 btrfs_queue_work(root->fs_info->submit_workers,
6048 &device->work);
6049 }
6050
6051 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
6052 struct bio *bio, u64 physical, int dev_nr,
6053 int rw, int async)
6054 {
6055 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
6056
6057 bio->bi_private = bbio;
6058 btrfs_io_bio(bio)->stripe_index = dev_nr;
6059 bio->bi_end_io = btrfs_end_bio;
6060 bio->bi_iter.bi_sector = physical >> 9;
6061 #ifdef DEBUG
6062 {
6063 struct rcu_string *name;
6064
6065 rcu_read_lock();
6066 name = rcu_dereference(dev->name);
6067 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
6068 "(%s id %llu), size=%u\n", rw,
6069 (u64)bio->bi_iter.bi_sector, (u_long)dev->bdev->bd_dev,
6070 name->str, dev->devid, bio->bi_iter.bi_size);
6071 rcu_read_unlock();
6072 }
6073 #endif
6074 bio->bi_bdev = dev->bdev;
6075
6076 btrfs_bio_counter_inc_noblocked(root->fs_info);
6077
6078 if (async)
6079 btrfs_schedule_bio(root, dev, rw, bio);
6080 else
6081 btrfsic_submit_bio(rw, bio);
6082 }
6083
6084 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
6085 {
6086 atomic_inc(&bbio->error);
6087 if (atomic_dec_and_test(&bbio->stripes_pending)) {
6088 /* Should be the original bio. */
6089 WARN_ON(bio != bbio->orig_bio);
6090
6091 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
6092 bio->bi_iter.bi_sector = logical >> 9;
6093 bio->bi_error = -EIO;
6094 btrfs_end_bbio(bbio, bio);
6095 }
6096 }
6097
6098 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
6099 int mirror_num, int async_submit)
6100 {
6101 struct btrfs_device *dev;
6102 struct bio *first_bio = bio;
6103 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
6104 u64 length = 0;
6105 u64 map_length;
6106 int ret;
6107 int dev_nr;
6108 int total_devs;
6109 struct btrfs_bio *bbio = NULL;
6110
6111 length = bio->bi_iter.bi_size;
6112 map_length = length;
6113
6114 btrfs_bio_counter_inc_blocked(root->fs_info);
6115 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
6116 mirror_num, 1);
6117 if (ret) {
6118 btrfs_bio_counter_dec(root->fs_info);
6119 return ret;
6120 }
6121
6122 total_devs = bbio->num_stripes;
6123 bbio->orig_bio = first_bio;
6124 bbio->private = first_bio->bi_private;
6125 bbio->end_io = first_bio->bi_end_io;
6126 bbio->fs_info = root->fs_info;
6127 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
6128
6129 if ((bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
6130 ((rw & WRITE) || (mirror_num > 1))) {
6131 /* In this case, map_length has been set to the length of
6132 a single stripe; not the whole write */
6133 if (rw & WRITE) {
6134 ret = raid56_parity_write(root, bio, bbio, map_length);
6135 } else {
6136 ret = raid56_parity_recover(root, bio, bbio, map_length,
6137 mirror_num, 1);
6138 }
6139
6140 btrfs_bio_counter_dec(root->fs_info);
6141 return ret;
6142 }
6143
6144 if (map_length < length) {
6145 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
6146 logical, length, map_length);
6147 BUG();
6148 }
6149
6150 for (dev_nr = 0; dev_nr < total_devs; dev_nr++) {
6151 dev = bbio->stripes[dev_nr].dev;
6152 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
6153 bbio_error(bbio, first_bio, logical);
6154 continue;
6155 }
6156
6157 if (dev_nr < total_devs - 1) {
6158 bio = btrfs_bio_clone(first_bio, GFP_NOFS);
6159 BUG_ON(!bio); /* -ENOMEM */
6160 } else
6161 bio = first_bio;
6162
6163 submit_stripe_bio(root, bbio, bio,
6164 bbio->stripes[dev_nr].physical, dev_nr, rw,
6165 async_submit);
6166 }
6167 btrfs_bio_counter_dec(root->fs_info);
6168 return 0;
6169 }
6170
6171 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
6172 u8 *uuid, u8 *fsid)
6173 {
6174 struct btrfs_device *device;
6175 struct btrfs_fs_devices *cur_devices;
6176
6177 cur_devices = fs_info->fs_devices;
6178 while (cur_devices) {
6179 if (!fsid ||
6180 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
6181 device = __find_device(&cur_devices->devices,
6182 devid, uuid);
6183 if (device)
6184 return device;
6185 }
6186 cur_devices = cur_devices->seed;
6187 }
6188 return NULL;
6189 }
6190
6191 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
6192 struct btrfs_fs_devices *fs_devices,
6193 u64 devid, u8 *dev_uuid)
6194 {
6195 struct btrfs_device *device;
6196
6197 device = btrfs_alloc_device(NULL, &devid, dev_uuid);
6198 if (IS_ERR(device))
6199 return NULL;
6200
6201 list_add(&device->dev_list, &fs_devices->devices);
6202 device->fs_devices = fs_devices;
6203 fs_devices->num_devices++;
6204
6205 device->missing = 1;
6206 fs_devices->missing_devices++;
6207
6208 return device;
6209 }
6210
6211 /**
6212 * btrfs_alloc_device - allocate struct btrfs_device
6213 * @fs_info: used only for generating a new devid, can be NULL if
6214 * devid is provided (i.e. @devid != NULL).
6215 * @devid: a pointer to devid for this device. If NULL a new devid
6216 * is generated.
6217 * @uuid: a pointer to UUID for this device. If NULL a new UUID
6218 * is generated.
6219 *
6220 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
6221 * on error. Returned struct is not linked onto any lists and can be
6222 * destroyed with kfree() right away.
6223 */
6224 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
6225 const u64 *devid,
6226 const u8 *uuid)
6227 {
6228 struct btrfs_device *dev;
6229 u64 tmp;
6230
6231 if (WARN_ON(!devid && !fs_info))
6232 return ERR_PTR(-EINVAL);
6233
6234 dev = __alloc_device();
6235 if (IS_ERR(dev))
6236 return dev;
6237
6238 if (devid)
6239 tmp = *devid;
6240 else {
6241 int ret;
6242
6243 ret = find_next_devid(fs_info, &tmp);
6244 if (ret) {
6245 kfree(dev);
6246 return ERR_PTR(ret);
6247 }
6248 }
6249 dev->devid = tmp;
6250
6251 if (uuid)
6252 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
6253 else
6254 generate_random_uuid(dev->uuid);
6255
6256 btrfs_init_work(&dev->work, btrfs_submit_helper,
6257 pending_bios_fn, NULL, NULL);
6258
6259 return dev;
6260 }
6261
6262 /* Return -EIO if any error, otherwise return 0. */
6263 static int btrfs_check_chunk_valid(struct btrfs_root *root,
6264 struct extent_buffer *leaf,
6265 struct btrfs_chunk *chunk, u64 logical)
6266 {
6267 u64 length;
6268 u64 stripe_len;
6269 u16 num_stripes;
6270 u16 sub_stripes;
6271 u64 type;
6272
6273 length = btrfs_chunk_length(leaf, chunk);
6274 stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6275 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
6276 sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
6277 type = btrfs_chunk_type(leaf, chunk);
6278
6279 if (!num_stripes) {
6280 btrfs_err(root->fs_info, "invalid chunk num_stripes: %u",
6281 num_stripes);
6282 return -EIO;
6283 }
6284 if (!IS_ALIGNED(logical, root->sectorsize)) {
6285 btrfs_err(root->fs_info,
6286 "invalid chunk logical %llu", logical);
6287 return -EIO;
6288 }
6289 if (btrfs_chunk_sector_size(leaf, chunk) != root->sectorsize) {
6290 btrfs_err(root->fs_info, "invalid chunk sectorsize %u",
6291 btrfs_chunk_sector_size(leaf, chunk));
6292 return -EIO;
6293 }
6294 if (!length || !IS_ALIGNED(length, root->sectorsize)) {
6295 btrfs_err(root->fs_info,
6296 "invalid chunk length %llu", length);
6297 return -EIO;
6298 }
6299 if (!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN) {
6300 btrfs_err(root->fs_info, "invalid chunk stripe length: %llu",
6301 stripe_len);
6302 return -EIO;
6303 }
6304 if (~(BTRFS_BLOCK_GROUP_TYPE_MASK | BTRFS_BLOCK_GROUP_PROFILE_MASK) &
6305 type) {
6306 btrfs_err(root->fs_info, "unrecognized chunk type: %llu",
6307 ~(BTRFS_BLOCK_GROUP_TYPE_MASK |
6308 BTRFS_BLOCK_GROUP_PROFILE_MASK) &
6309 btrfs_chunk_type(leaf, chunk));
6310 return -EIO;
6311 }
6312 if ((type & BTRFS_BLOCK_GROUP_RAID10 && sub_stripes != 2) ||
6313 (type & BTRFS_BLOCK_GROUP_RAID1 && num_stripes < 1) ||
6314 (type & BTRFS_BLOCK_GROUP_RAID5 && num_stripes < 2) ||
6315 (type & BTRFS_BLOCK_GROUP_RAID6 && num_stripes < 3) ||
6316 (type & BTRFS_BLOCK_GROUP_DUP && num_stripes > 2) ||
6317 ((type & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0 &&
6318 num_stripes != 1)) {
6319 btrfs_err(root->fs_info,
6320 "invalid num_stripes:sub_stripes %u:%u for profile %llu",
6321 num_stripes, sub_stripes,
6322 type & BTRFS_BLOCK_GROUP_PROFILE_MASK);
6323 return -EIO;
6324 }
6325
6326 return 0;
6327 }
6328
6329 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
6330 struct extent_buffer *leaf,
6331 struct btrfs_chunk *chunk)
6332 {
6333 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
6334 struct map_lookup *map;
6335 struct extent_map *em;
6336 u64 logical;
6337 u64 length;
6338 u64 stripe_len;
6339 u64 devid;
6340 u8 uuid[BTRFS_UUID_SIZE];
6341 int num_stripes;
6342 int ret;
6343 int i;
6344
6345 logical = key->offset;
6346 length = btrfs_chunk_length(leaf, chunk);
6347 stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6348 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
6349
6350 ret = btrfs_check_chunk_valid(root, leaf, chunk, logical);
6351 if (ret)
6352 return ret;
6353
6354 read_lock(&map_tree->map_tree.lock);
6355 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
6356 read_unlock(&map_tree->map_tree.lock);
6357
6358 /* already mapped? */
6359 if (em && em->start <= logical && em->start + em->len > logical) {
6360 free_extent_map(em);
6361 return 0;
6362 } else if (em) {
6363 free_extent_map(em);
6364 }
6365
6366 em = alloc_extent_map();
6367 if (!em)
6368 return -ENOMEM;
6369 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
6370 if (!map) {
6371 free_extent_map(em);
6372 return -ENOMEM;
6373 }
6374
6375 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
6376 em->map_lookup = map;
6377 em->start = logical;
6378 em->len = length;
6379 em->orig_start = 0;
6380 em->block_start = 0;
6381 em->block_len = em->len;
6382
6383 map->num_stripes = num_stripes;
6384 map->io_width = btrfs_chunk_io_width(leaf, chunk);
6385 map->io_align = btrfs_chunk_io_align(leaf, chunk);
6386 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
6387 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
6388 map->type = btrfs_chunk_type(leaf, chunk);
6389 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
6390 for (i = 0; i < num_stripes; i++) {
6391 map->stripes[i].physical =
6392 btrfs_stripe_offset_nr(leaf, chunk, i);
6393 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
6394 read_extent_buffer(leaf, uuid, (unsigned long)
6395 btrfs_stripe_dev_uuid_nr(chunk, i),
6396 BTRFS_UUID_SIZE);
6397 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
6398 uuid, NULL);
6399 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
6400 free_extent_map(em);
6401 return -EIO;
6402 }
6403 if (!map->stripes[i].dev) {
6404 map->stripes[i].dev =
6405 add_missing_dev(root, root->fs_info->fs_devices,
6406 devid, uuid);
6407 if (!map->stripes[i].dev) {
6408 free_extent_map(em);
6409 return -EIO;
6410 }
6411 btrfs_warn(root->fs_info, "devid %llu uuid %pU is missing",
6412 devid, uuid);
6413 }
6414 map->stripes[i].dev->in_fs_metadata = 1;
6415 }
6416
6417 write_lock(&map_tree->map_tree.lock);
6418 ret = add_extent_mapping(&map_tree->map_tree, em, 0);
6419 write_unlock(&map_tree->map_tree.lock);
6420 BUG_ON(ret); /* Tree corruption */
6421 free_extent_map(em);
6422
6423 return 0;
6424 }
6425
6426 static void fill_device_from_item(struct extent_buffer *leaf,
6427 struct btrfs_dev_item *dev_item,
6428 struct btrfs_device *device)
6429 {
6430 unsigned long ptr;
6431
6432 device->devid = btrfs_device_id(leaf, dev_item);
6433 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
6434 device->total_bytes = device->disk_total_bytes;
6435 device->commit_total_bytes = device->disk_total_bytes;
6436 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
6437 device->commit_bytes_used = device->bytes_used;
6438 device->type = btrfs_device_type(leaf, dev_item);
6439 device->io_align = btrfs_device_io_align(leaf, dev_item);
6440 device->io_width = btrfs_device_io_width(leaf, dev_item);
6441 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
6442 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
6443 device->is_tgtdev_for_dev_replace = 0;
6444
6445 ptr = btrfs_device_uuid(dev_item);
6446 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
6447 }
6448
6449 static struct btrfs_fs_devices *open_seed_devices(struct btrfs_root *root,
6450 u8 *fsid)
6451 {
6452 struct btrfs_fs_devices *fs_devices;
6453 int ret;
6454
6455 BUG_ON(!mutex_is_locked(&uuid_mutex));
6456
6457 fs_devices = root->fs_info->fs_devices->seed;
6458 while (fs_devices) {
6459 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE))
6460 return fs_devices;
6461
6462 fs_devices = fs_devices->seed;
6463 }
6464
6465 fs_devices = find_fsid(fsid);
6466 if (!fs_devices) {
6467 if (!btrfs_test_opt(root, DEGRADED))
6468 return ERR_PTR(-ENOENT);
6469
6470 fs_devices = alloc_fs_devices(fsid);
6471 if (IS_ERR(fs_devices))
6472 return fs_devices;
6473
6474 fs_devices->seeding = 1;
6475 fs_devices->opened = 1;
6476 return fs_devices;
6477 }
6478
6479 fs_devices = clone_fs_devices(fs_devices);
6480 if (IS_ERR(fs_devices))
6481 return fs_devices;
6482
6483 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
6484 root->fs_info->bdev_holder);
6485 if (ret) {
6486 free_fs_devices(fs_devices);
6487 fs_devices = ERR_PTR(ret);
6488 goto out;
6489 }
6490
6491 if (!fs_devices->seeding) {
6492 __btrfs_close_devices(fs_devices);
6493 free_fs_devices(fs_devices);
6494 fs_devices = ERR_PTR(-EINVAL);
6495 goto out;
6496 }
6497
6498 fs_devices->seed = root->fs_info->fs_devices->seed;
6499 root->fs_info->fs_devices->seed = fs_devices;
6500 out:
6501 return fs_devices;
6502 }
6503
6504 static int read_one_dev(struct btrfs_root *root,
6505 struct extent_buffer *leaf,
6506 struct btrfs_dev_item *dev_item)
6507 {
6508 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6509 struct btrfs_device *device;
6510 u64 devid;
6511 int ret;
6512 u8 fs_uuid[BTRFS_UUID_SIZE];
6513 u8 dev_uuid[BTRFS_UUID_SIZE];
6514
6515 devid = btrfs_device_id(leaf, dev_item);
6516 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
6517 BTRFS_UUID_SIZE);
6518 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
6519 BTRFS_UUID_SIZE);
6520
6521 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
6522 fs_devices = open_seed_devices(root, fs_uuid);
6523 if (IS_ERR(fs_devices))
6524 return PTR_ERR(fs_devices);
6525 }
6526
6527 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
6528 if (!device) {
6529 if (!btrfs_test_opt(root, DEGRADED))
6530 return -EIO;
6531
6532 device = add_missing_dev(root, fs_devices, devid, dev_uuid);
6533 if (!device)
6534 return -ENOMEM;
6535 btrfs_warn(root->fs_info, "devid %llu uuid %pU missing",
6536 devid, dev_uuid);
6537 } else {
6538 if (!device->bdev && !btrfs_test_opt(root, DEGRADED))
6539 return -EIO;
6540
6541 if(!device->bdev && !device->missing) {
6542 /*
6543 * this happens when a device that was properly setup
6544 * in the device info lists suddenly goes bad.
6545 * device->bdev is NULL, and so we have to set
6546 * device->missing to one here
6547 */
6548 device->fs_devices->missing_devices++;
6549 device->missing = 1;
6550 }
6551
6552 /* Move the device to its own fs_devices */
6553 if (device->fs_devices != fs_devices) {
6554 ASSERT(device->missing);
6555
6556 list_move(&device->dev_list, &fs_devices->devices);
6557 device->fs_devices->num_devices--;
6558 fs_devices->num_devices++;
6559
6560 device->fs_devices->missing_devices--;
6561 fs_devices->missing_devices++;
6562
6563 device->fs_devices = fs_devices;
6564 }
6565 }
6566
6567 if (device->fs_devices != root->fs_info->fs_devices) {
6568 BUG_ON(device->writeable);
6569 if (device->generation !=
6570 btrfs_device_generation(leaf, dev_item))
6571 return -EINVAL;
6572 }
6573
6574 fill_device_from_item(leaf, dev_item, device);
6575 device->in_fs_metadata = 1;
6576 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
6577 device->fs_devices->total_rw_bytes += device->total_bytes;
6578 spin_lock(&root->fs_info->free_chunk_lock);
6579 root->fs_info->free_chunk_space += device->total_bytes -
6580 device->bytes_used;
6581 spin_unlock(&root->fs_info->free_chunk_lock);
6582 }
6583 ret = 0;
6584 return ret;
6585 }
6586
6587 int btrfs_read_sys_array(struct btrfs_root *root)
6588 {
6589 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
6590 struct extent_buffer *sb;
6591 struct btrfs_disk_key *disk_key;
6592 struct btrfs_chunk *chunk;
6593 u8 *array_ptr;
6594 unsigned long sb_array_offset;
6595 int ret = 0;
6596 u32 num_stripes;
6597 u32 array_size;
6598 u32 len = 0;
6599 u32 cur_offset;
6600 u64 type;
6601 struct btrfs_key key;
6602
6603 ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
6604 /*
6605 * This will create extent buffer of nodesize, superblock size is
6606 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
6607 * overallocate but we can keep it as-is, only the first page is used.
6608 */
6609 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
6610 if (IS_ERR(sb))
6611 return PTR_ERR(sb);
6612 set_extent_buffer_uptodate(sb);
6613 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
6614 /*
6615 * The sb extent buffer is artificial and just used to read the system array.
6616 * set_extent_buffer_uptodate() call does not properly mark all it's
6617 * pages up-to-date when the page is larger: extent does not cover the
6618 * whole page and consequently check_page_uptodate does not find all
6619 * the page's extents up-to-date (the hole beyond sb),
6620 * write_extent_buffer then triggers a WARN_ON.
6621 *
6622 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
6623 * but sb spans only this function. Add an explicit SetPageUptodate call
6624 * to silence the warning eg. on PowerPC 64.
6625 */
6626 if (PAGE_SIZE > BTRFS_SUPER_INFO_SIZE)
6627 SetPageUptodate(sb->pages[0]);
6628
6629 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
6630 array_size = btrfs_super_sys_array_size(super_copy);
6631
6632 array_ptr = super_copy->sys_chunk_array;
6633 sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
6634 cur_offset = 0;
6635
6636 while (cur_offset < array_size) {
6637 disk_key = (struct btrfs_disk_key *)array_ptr;
6638 len = sizeof(*disk_key);
6639 if (cur_offset + len > array_size)
6640 goto out_short_read;
6641
6642 btrfs_disk_key_to_cpu(&key, disk_key);
6643
6644 array_ptr += len;
6645 sb_array_offset += len;
6646 cur_offset += len;
6647
6648 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6649 chunk = (struct btrfs_chunk *)sb_array_offset;
6650 /*
6651 * At least one btrfs_chunk with one stripe must be
6652 * present, exact stripe count check comes afterwards
6653 */
6654 len = btrfs_chunk_item_size(1);
6655 if (cur_offset + len > array_size)
6656 goto out_short_read;
6657
6658 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
6659 if (!num_stripes) {
6660 printk(KERN_ERR
6661 "BTRFS: invalid number of stripes %u in sys_array at offset %u\n",
6662 num_stripes, cur_offset);
6663 ret = -EIO;
6664 break;
6665 }
6666
6667 type = btrfs_chunk_type(sb, chunk);
6668 if ((type & BTRFS_BLOCK_GROUP_SYSTEM) == 0) {
6669 btrfs_err(root->fs_info,
6670 "invalid chunk type %llu in sys_array at offset %u",
6671 type, cur_offset);
6672 ret = -EIO;
6673 break;
6674 }
6675
6676 len = btrfs_chunk_item_size(num_stripes);
6677 if (cur_offset + len > array_size)
6678 goto out_short_read;
6679
6680 ret = read_one_chunk(root, &key, sb, chunk);
6681 if (ret)
6682 break;
6683 } else {
6684 printk(KERN_ERR
6685 "BTRFS: unexpected item type %u in sys_array at offset %u\n",
6686 (u32)key.type, cur_offset);
6687 ret = -EIO;
6688 break;
6689 }
6690 array_ptr += len;
6691 sb_array_offset += len;
6692 cur_offset += len;
6693 }
6694 clear_extent_buffer_uptodate(sb);
6695 free_extent_buffer_stale(sb);
6696 return ret;
6697
6698 out_short_read:
6699 printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
6700 len, cur_offset);
6701 clear_extent_buffer_uptodate(sb);
6702 free_extent_buffer_stale(sb);
6703 return -EIO;
6704 }
6705
6706 int btrfs_read_chunk_tree(struct btrfs_root *root)
6707 {
6708 struct btrfs_path *path;
6709 struct extent_buffer *leaf;
6710 struct btrfs_key key;
6711 struct btrfs_key found_key;
6712 int ret;
6713 int slot;
6714 u64 total_dev = 0;
6715
6716 root = root->fs_info->chunk_root;
6717
6718 path = btrfs_alloc_path();
6719 if (!path)
6720 return -ENOMEM;
6721
6722 mutex_lock(&uuid_mutex);
6723 lock_chunks(root);
6724
6725 /*
6726 * Read all device items, and then all the chunk items. All
6727 * device items are found before any chunk item (their object id
6728 * is smaller than the lowest possible object id for a chunk
6729 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
6730 */
6731 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
6732 key.offset = 0;
6733 key.type = 0;
6734 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6735 if (ret < 0)
6736 goto error;
6737 while (1) {
6738 leaf = path->nodes[0];
6739 slot = path->slots[0];
6740 if (slot >= btrfs_header_nritems(leaf)) {
6741 ret = btrfs_next_leaf(root, path);
6742 if (ret == 0)
6743 continue;
6744 if (ret < 0)
6745 goto error;
6746 break;
6747 }
6748 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6749 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
6750 struct btrfs_dev_item *dev_item;
6751 dev_item = btrfs_item_ptr(leaf, slot,
6752 struct btrfs_dev_item);
6753 ret = read_one_dev(root, leaf, dev_item);
6754 if (ret)
6755 goto error;
6756 total_dev++;
6757 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
6758 struct btrfs_chunk *chunk;
6759 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
6760 ret = read_one_chunk(root, &found_key, leaf, chunk);
6761 if (ret)
6762 goto error;
6763 }
6764 path->slots[0]++;
6765 }
6766
6767 /*
6768 * After loading chunk tree, we've got all device information,
6769 * do another round of validation checks.
6770 */
6771 if (total_dev != root->fs_info->fs_devices->total_devices) {
6772 btrfs_err(root->fs_info,
6773 "super_num_devices %llu mismatch with num_devices %llu found here",
6774 btrfs_super_num_devices(root->fs_info->super_copy),
6775 total_dev);
6776 ret = -EINVAL;
6777 goto error;
6778 }
6779 if (btrfs_super_total_bytes(root->fs_info->super_copy) <
6780 root->fs_info->fs_devices->total_rw_bytes) {
6781 btrfs_err(root->fs_info,
6782 "super_total_bytes %llu mismatch with fs_devices total_rw_bytes %llu",
6783 btrfs_super_total_bytes(root->fs_info->super_copy),
6784 root->fs_info->fs_devices->total_rw_bytes);
6785 ret = -EINVAL;
6786 goto error;
6787 }
6788 ret = 0;
6789 error:
6790 unlock_chunks(root);
6791 mutex_unlock(&uuid_mutex);
6792
6793 btrfs_free_path(path);
6794 return ret;
6795 }
6796
6797 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
6798 {
6799 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6800 struct btrfs_device *device;
6801
6802 while (fs_devices) {
6803 mutex_lock(&fs_devices->device_list_mutex);
6804 list_for_each_entry(device, &fs_devices->devices, dev_list)
6805 device->dev_root = fs_info->dev_root;
6806 mutex_unlock(&fs_devices->device_list_mutex);
6807
6808 fs_devices = fs_devices->seed;
6809 }
6810 }
6811
6812 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
6813 {
6814 int i;
6815
6816 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6817 btrfs_dev_stat_reset(dev, i);
6818 }
6819
6820 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
6821 {
6822 struct btrfs_key key;
6823 struct btrfs_key found_key;
6824 struct btrfs_root *dev_root = fs_info->dev_root;
6825 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6826 struct extent_buffer *eb;
6827 int slot;
6828 int ret = 0;
6829 struct btrfs_device *device;
6830 struct btrfs_path *path = NULL;
6831 int i;
6832
6833 path = btrfs_alloc_path();
6834 if (!path) {
6835 ret = -ENOMEM;
6836 goto out;
6837 }
6838
6839 mutex_lock(&fs_devices->device_list_mutex);
6840 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6841 int item_size;
6842 struct btrfs_dev_stats_item *ptr;
6843
6844 key.objectid = BTRFS_DEV_STATS_OBJECTID;
6845 key.type = BTRFS_PERSISTENT_ITEM_KEY;
6846 key.offset = device->devid;
6847 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
6848 if (ret) {
6849 __btrfs_reset_dev_stats(device);
6850 device->dev_stats_valid = 1;
6851 btrfs_release_path(path);
6852 continue;
6853 }
6854 slot = path->slots[0];
6855 eb = path->nodes[0];
6856 btrfs_item_key_to_cpu(eb, &found_key, slot);
6857 item_size = btrfs_item_size_nr(eb, slot);
6858
6859 ptr = btrfs_item_ptr(eb, slot,
6860 struct btrfs_dev_stats_item);
6861
6862 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6863 if (item_size >= (1 + i) * sizeof(__le64))
6864 btrfs_dev_stat_set(device, i,
6865 btrfs_dev_stats_value(eb, ptr, i));
6866 else
6867 btrfs_dev_stat_reset(device, i);
6868 }
6869
6870 device->dev_stats_valid = 1;
6871 btrfs_dev_stat_print_on_load(device);
6872 btrfs_release_path(path);
6873 }
6874 mutex_unlock(&fs_devices->device_list_mutex);
6875
6876 out:
6877 btrfs_free_path(path);
6878 return ret < 0 ? ret : 0;
6879 }
6880
6881 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
6882 struct btrfs_root *dev_root,
6883 struct btrfs_device *device)
6884 {
6885 struct btrfs_path *path;
6886 struct btrfs_key key;
6887 struct extent_buffer *eb;
6888 struct btrfs_dev_stats_item *ptr;
6889 int ret;
6890 int i;
6891
6892 key.objectid = BTRFS_DEV_STATS_OBJECTID;
6893 key.type = BTRFS_PERSISTENT_ITEM_KEY;
6894 key.offset = device->devid;
6895
6896 path = btrfs_alloc_path();
6897 BUG_ON(!path);
6898 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
6899 if (ret < 0) {
6900 btrfs_warn_in_rcu(dev_root->fs_info,
6901 "error %d while searching for dev_stats item for device %s",
6902 ret, rcu_str_deref(device->name));
6903 goto out;
6904 }
6905
6906 if (ret == 0 &&
6907 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
6908 /* need to delete old one and insert a new one */
6909 ret = btrfs_del_item(trans, dev_root, path);
6910 if (ret != 0) {
6911 btrfs_warn_in_rcu(dev_root->fs_info,
6912 "delete too small dev_stats item for device %s failed %d",
6913 rcu_str_deref(device->name), ret);
6914 goto out;
6915 }
6916 ret = 1;
6917 }
6918
6919 if (ret == 1) {
6920 /* need to insert a new item */
6921 btrfs_release_path(path);
6922 ret = btrfs_insert_empty_item(trans, dev_root, path,
6923 &key, sizeof(*ptr));
6924 if (ret < 0) {
6925 btrfs_warn_in_rcu(dev_root->fs_info,
6926 "insert dev_stats item for device %s failed %d",
6927 rcu_str_deref(device->name), ret);
6928 goto out;
6929 }
6930 }
6931
6932 eb = path->nodes[0];
6933 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
6934 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6935 btrfs_set_dev_stats_value(eb, ptr, i,
6936 btrfs_dev_stat_read(device, i));
6937 btrfs_mark_buffer_dirty(eb);
6938
6939 out:
6940 btrfs_free_path(path);
6941 return ret;
6942 }
6943
6944 /*
6945 * called from commit_transaction. Writes all changed device stats to disk.
6946 */
6947 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
6948 struct btrfs_fs_info *fs_info)
6949 {
6950 struct btrfs_root *dev_root = fs_info->dev_root;
6951 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6952 struct btrfs_device *device;
6953 int stats_cnt;
6954 int ret = 0;
6955
6956 mutex_lock(&fs_devices->device_list_mutex);
6957 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6958 if (!device->dev_stats_valid || !btrfs_dev_stats_dirty(device))
6959 continue;
6960
6961 stats_cnt = atomic_read(&device->dev_stats_ccnt);
6962 ret = update_dev_stat_item(trans, dev_root, device);
6963 if (!ret)
6964 atomic_sub(stats_cnt, &device->dev_stats_ccnt);
6965 }
6966 mutex_unlock(&fs_devices->device_list_mutex);
6967
6968 return ret;
6969 }
6970
6971 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
6972 {
6973 btrfs_dev_stat_inc(dev, index);
6974 btrfs_dev_stat_print_on_error(dev);
6975 }
6976
6977 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
6978 {
6979 if (!dev->dev_stats_valid)
6980 return;
6981 btrfs_err_rl_in_rcu(dev->dev_root->fs_info,
6982 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
6983 rcu_str_deref(dev->name),
6984 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6985 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6986 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6987 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6988 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6989 }
6990
6991 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
6992 {
6993 int i;
6994
6995 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6996 if (btrfs_dev_stat_read(dev, i) != 0)
6997 break;
6998 if (i == BTRFS_DEV_STAT_VALUES_MAX)
6999 return; /* all values == 0, suppress message */
7000
7001 btrfs_info_in_rcu(dev->dev_root->fs_info,
7002 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u",
7003 rcu_str_deref(dev->name),
7004 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
7005 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
7006 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
7007 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
7008 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
7009 }
7010
7011 int btrfs_get_dev_stats(struct btrfs_root *root,
7012 struct btrfs_ioctl_get_dev_stats *stats)
7013 {
7014 struct btrfs_device *dev;
7015 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
7016 int i;
7017
7018 mutex_lock(&fs_devices->device_list_mutex);
7019 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
7020 mutex_unlock(&fs_devices->device_list_mutex);
7021
7022 if (!dev) {
7023 btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
7024 return -ENODEV;
7025 } else if (!dev->dev_stats_valid) {
7026 btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
7027 return -ENODEV;
7028 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
7029 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
7030 if (stats->nr_items > i)
7031 stats->values[i] =
7032 btrfs_dev_stat_read_and_reset(dev, i);
7033 else
7034 btrfs_dev_stat_reset(dev, i);
7035 }
7036 } else {
7037 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
7038 if (stats->nr_items > i)
7039 stats->values[i] = btrfs_dev_stat_read(dev, i);
7040 }
7041 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
7042 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
7043 return 0;
7044 }
7045
7046 void btrfs_scratch_superblocks(struct block_device *bdev, char *device_path)
7047 {
7048 struct buffer_head *bh;
7049 struct btrfs_super_block *disk_super;
7050 int copy_num;
7051
7052 if (!bdev)
7053 return;
7054
7055 for (copy_num = 0; copy_num < BTRFS_SUPER_MIRROR_MAX;
7056 copy_num++) {
7057
7058 if (btrfs_read_dev_one_super(bdev, copy_num, &bh))
7059 continue;
7060
7061 disk_super = (struct btrfs_super_block *)bh->b_data;
7062
7063 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
7064 set_buffer_dirty(bh);
7065 sync_dirty_buffer(bh);
7066 brelse(bh);
7067 }
7068
7069 /* Notify udev that device has changed */
7070 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
7071
7072 /* Update ctime/mtime for device path for libblkid */
7073 update_dev_time(device_path);
7074 }
7075
7076 /*
7077 * Update the size of all devices, which is used for writing out the
7078 * super blocks.
7079 */
7080 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info)
7081 {
7082 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7083 struct btrfs_device *curr, *next;
7084
7085 if (list_empty(&fs_devices->resized_devices))
7086 return;
7087
7088 mutex_lock(&fs_devices->device_list_mutex);
7089 lock_chunks(fs_info->dev_root);
7090 list_for_each_entry_safe(curr, next, &fs_devices->resized_devices,
7091 resized_list) {
7092 list_del_init(&curr->resized_list);
7093 curr->commit_total_bytes = curr->disk_total_bytes;
7094 }
7095 unlock_chunks(fs_info->dev_root);
7096 mutex_unlock(&fs_devices->device_list_mutex);
7097 }
7098
7099 /* Must be invoked during the transaction commit */
7100 void btrfs_update_commit_device_bytes_used(struct btrfs_root *root,
7101 struct btrfs_transaction *transaction)
7102 {
7103 struct extent_map *em;
7104 struct map_lookup *map;
7105 struct btrfs_device *dev;
7106 int i;
7107
7108 if (list_empty(&transaction->pending_chunks))
7109 return;
7110
7111 /* In order to kick the device replace finish process */
7112 lock_chunks(root);
7113 list_for_each_entry(em, &transaction->pending_chunks, list) {
7114 map = em->map_lookup;
7115
7116 for (i = 0; i < map->num_stripes; i++) {
7117 dev = map->stripes[i].dev;
7118 dev->commit_bytes_used = dev->bytes_used;
7119 }
7120 }
7121 unlock_chunks(root);
7122 }
7123
7124 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info)
7125 {
7126 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7127 while (fs_devices) {
7128 fs_devices->fs_info = fs_info;
7129 fs_devices = fs_devices->seed;
7130 }
7131 }
7132
7133 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info)
7134 {
7135 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
7136 while (fs_devices) {
7137 fs_devices->fs_info = NULL;
7138 fs_devices = fs_devices->seed;
7139 }
7140 }
7141
7142 static void btrfs_close_one_device(struct btrfs_device *device)
7143 {
7144 struct btrfs_fs_devices *fs_devices = device->fs_devices;
7145 struct btrfs_device *new_device;
7146 struct rcu_string *name;
7147
7148 if (device->bdev)
7149 fs_devices->open_devices--;
7150
7151 if (device->writeable &&
7152 device->devid != BTRFS_DEV_REPLACE_DEVID) {
7153 list_del_init(&device->dev_alloc_list);
7154 fs_devices->rw_devices--;
7155 }
7156
7157 if (device->missing)
7158 fs_devices->missing_devices--;
7159
7160 new_device = btrfs_alloc_device(NULL, &device->devid,
7161 device->uuid);
7162 BUG_ON(IS_ERR(new_device)); /* -ENOMEM */
7163
7164 /* Safe because we are under uuid_mutex */
7165 if (device->name) {
7166 name = rcu_string_strdup(device->name->str, GFP_NOFS);
7167 BUG_ON(!name); /* -ENOMEM */
7168 rcu_assign_pointer(new_device->name, name);
7169 }
7170
7171 list_replace_rcu(&device->dev_list, &new_device->dev_list);
7172 new_device->fs_devices = device->fs_devices;
7173
7174 call_rcu(&device->rcu, free_device);
7175 }