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qmi_wwan: add Sierra Wireless EM74xx device ID
[linux/fpc-iii.git] / fs / btrfs / volumes.c
blob81bec9fd8f199a061d070750179fdb9ec4f39b56
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18 #include <linux/sched.h>
19 #include <linux/bio.h>
20 #include <linux/slab.h>
21 #include <linux/buffer_head.h>
22 #include <linux/blkdev.h>
23 #include <linux/random.h>
24 #include <linux/iocontext.h>
25 #include <linux/capability.h>
26 #include <linux/ratelimit.h>
27 #include <linux/kthread.h>
28 #include <linux/raid/pq.h>
29 #include <linux/semaphore.h>
30 #include <asm/div64.h>
31 #include "ctree.h"
32 #include "extent_map.h"
33 #include "disk-io.h"
34 #include "transaction.h"
35 #include "print-tree.h"
36 #include "volumes.h"
37 #include "raid56.h"
38 #include "async-thread.h"
39 #include "check-integrity.h"
40 #include "rcu-string.h"
41 #include "math.h"
42 #include "dev-replace.h"
43 #include "sysfs.h"
44
45 static int init_first_rw_device(struct btrfs_trans_handle *trans,
46 struct btrfs_root *root,
47 struct btrfs_device *device);
48 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
49 static void __btrfs_reset_dev_stats(struct btrfs_device *dev);
50 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev);
51 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
52
53 static DEFINE_MUTEX(uuid_mutex);
54 static LIST_HEAD(fs_uuids);
55
56 static void lock_chunks(struct btrfs_root *root)
57 {
58 mutex_lock(&root->fs_info->chunk_mutex);
59 }
60
61 static void unlock_chunks(struct btrfs_root *root)
62 {
63 mutex_unlock(&root->fs_info->chunk_mutex);
64 }
65
66 static struct btrfs_fs_devices *__alloc_fs_devices(void)
67 {
68 struct btrfs_fs_devices *fs_devs;
69
70 fs_devs = kzalloc(sizeof(*fs_devs), GFP_NOFS);
71 if (!fs_devs)
72 return ERR_PTR(-ENOMEM);
73
74 mutex_init(&fs_devs->device_list_mutex);
75
76 INIT_LIST_HEAD(&fs_devs->devices);
77 INIT_LIST_HEAD(&fs_devs->alloc_list);
78 INIT_LIST_HEAD(&fs_devs->list);
79
80 return fs_devs;
81 }
82
83 /**
84 * alloc_fs_devices - allocate struct btrfs_fs_devices
85 * @fsid: a pointer to UUID for this FS. If NULL a new UUID is
86 * generated.
87 *
88 * Return: a pointer to a new &struct btrfs_fs_devices on success;
89 * ERR_PTR() on error. Returned struct is not linked onto any lists and
90 * can be destroyed with kfree() right away.
91 */
92 static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid)
93 {
94 struct btrfs_fs_devices *fs_devs;
95
96 fs_devs = __alloc_fs_devices();
97 if (IS_ERR(fs_devs))
98 return fs_devs;
99
100 if (fsid)
101 memcpy(fs_devs->fsid, fsid, BTRFS_FSID_SIZE);
102 else
103 generate_random_uuid(fs_devs->fsid);
104
105 return fs_devs;
106 }
107
108 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
109 {
110 struct btrfs_device *device;
111 WARN_ON(fs_devices->opened);
112 while (!list_empty(&fs_devices->devices)) {
113 device = list_entry(fs_devices->devices.next,
114 struct btrfs_device, dev_list);
115 list_del(&device->dev_list);
116 rcu_string_free(device->name);
117 kfree(device);
118 }
119 kfree(fs_devices);
120 }
121
122 static void btrfs_kobject_uevent(struct block_device *bdev,
123 enum kobject_action action)
124 {
125 int ret;
126
127 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
128 if (ret)
129 pr_warn("BTRFS: Sending event '%d' to kobject: '%s' (%p): failed\n",
130 action,
131 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
132 &disk_to_dev(bdev->bd_disk)->kobj);
133 }
134
135 void btrfs_cleanup_fs_uuids(void)
136 {
137 struct btrfs_fs_devices *fs_devices;
138
139 while (!list_empty(&fs_uuids)) {
140 fs_devices = list_entry(fs_uuids.next,
141 struct btrfs_fs_devices, list);
142 list_del(&fs_devices->list);
143 free_fs_devices(fs_devices);
144 }
145 }
146
147 static struct btrfs_device *__alloc_device(void)
148 {
149 struct btrfs_device *dev;
150
151 dev = kzalloc(sizeof(*dev), GFP_NOFS);
152 if (!dev)
153 return ERR_PTR(-ENOMEM);
154
155 INIT_LIST_HEAD(&dev->dev_list);
156 INIT_LIST_HEAD(&dev->dev_alloc_list);
157
158 spin_lock_init(&dev->io_lock);
159
160 spin_lock_init(&dev->reada_lock);
161 atomic_set(&dev->reada_in_flight, 0);
162 INIT_RADIX_TREE(&dev->reada_zones, GFP_NOFS & ~__GFP_WAIT);
163 INIT_RADIX_TREE(&dev->reada_extents, GFP_NOFS & ~__GFP_WAIT);
164
165 return dev;
166 }
167
168 static noinline struct btrfs_device *__find_device(struct list_head *head,
169 u64 devid, u8 *uuid)
170 {
171 struct btrfs_device *dev;
172
173 list_for_each_entry(dev, head, dev_list) {
174 if (dev->devid == devid &&
175 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
176 return dev;
177 }
178 }
179 return NULL;
180 }
181
182 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
183 {
184 struct btrfs_fs_devices *fs_devices;
185
186 list_for_each_entry(fs_devices, &fs_uuids, list) {
187 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
188 return fs_devices;
189 }
190 return NULL;
191 }
192
193 static int
194 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
195 int flush, struct block_device **bdev,
196 struct buffer_head **bh)
197 {
198 int ret;
199
200 *bdev = blkdev_get_by_path(device_path, flags, holder);
201
202 if (IS_ERR(*bdev)) {
203 ret = PTR_ERR(*bdev);
204 printk(KERN_INFO "BTRFS: open %s failed\n", device_path);
205 goto error;
206 }
207
208 if (flush)
209 filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
210 ret = set_blocksize(*bdev, 4096);
211 if (ret) {
212 blkdev_put(*bdev, flags);
213 goto error;
214 }
215 invalidate_bdev(*bdev);
216 *bh = btrfs_read_dev_super(*bdev);
217 if (!*bh) {
218 ret = -EINVAL;
219 blkdev_put(*bdev, flags);
220 goto error;
221 }
222
223 return 0;
224
225 error:
226 *bdev = NULL;
227 *bh = NULL;
228 return ret;
229 }
230
231 static void requeue_list(struct btrfs_pending_bios *pending_bios,
232 struct bio *head, struct bio *tail)
233 {
234
235 struct bio *old_head;
236
237 old_head = pending_bios->head;
238 pending_bios->head = head;
239 if (pending_bios->tail)
240 tail->bi_next = old_head;
241 else
242 pending_bios->tail = tail;
243 }
244
245 /*
246 * we try to collect pending bios for a device so we don't get a large
247 * number of procs sending bios down to the same device. This greatly
248 * improves the schedulers ability to collect and merge the bios.
249 *
250 * But, it also turns into a long list of bios to process and that is sure
251 * to eventually make the worker thread block. The solution here is to
252 * make some progress and then put this work struct back at the end of
253 * the list if the block device is congested. This way, multiple devices
254 * can make progress from a single worker thread.
255 */
256 static noinline void run_scheduled_bios(struct btrfs_device *device)
257 {
258 struct bio *pending;
259 struct backing_dev_info *bdi;
260 struct btrfs_fs_info *fs_info;
261 struct btrfs_pending_bios *pending_bios;
262 struct bio *tail;
263 struct bio *cur;
264 int again = 0;
265 unsigned long num_run;
266 unsigned long batch_run = 0;
267 unsigned long limit;
268 unsigned long last_waited = 0;
269 int force_reg = 0;
270 int sync_pending = 0;
271 struct blk_plug plug;
272
273 /*
274 * this function runs all the bios we've collected for
275 * a particular device. We don't want to wander off to
276 * another device without first sending all of these down.
277 * So, setup a plug here and finish it off before we return
278 */
279 blk_start_plug(&plug);
280
281 bdi = blk_get_backing_dev_info(device->bdev);
282 fs_info = device->dev_root->fs_info;
283 limit = btrfs_async_submit_limit(fs_info);
284 limit = limit * 2 / 3;
285
286 loop:
287 spin_lock(&device->io_lock);
288
289 loop_lock:
290 num_run = 0;
291
292 /* take all the bios off the list at once and process them
293 * later on (without the lock held). But, remember the
294 * tail and other pointers so the bios can be properly reinserted
295 * into the list if we hit congestion
296 */
297 if (!force_reg && device->pending_sync_bios.head) {
298 pending_bios = &device->pending_sync_bios;
299 force_reg = 1;
300 } else {
301 pending_bios = &device->pending_bios;
302 force_reg = 0;
303 }
304
305 pending = pending_bios->head;
306 tail = pending_bios->tail;
307 WARN_ON(pending && !tail);
308
309 /*
310 * if pending was null this time around, no bios need processing
311 * at all and we can stop. Otherwise it'll loop back up again
312 * and do an additional check so no bios are missed.
313 *
314 * device->running_pending is used to synchronize with the
315 * schedule_bio code.
316 */
317 if (device->pending_sync_bios.head == NULL &&
318 device->pending_bios.head == NULL) {
319 again = 0;
320 device->running_pending = 0;
321 } else {
322 again = 1;
323 device->running_pending = 1;
324 }
325
326 pending_bios->head = NULL;
327 pending_bios->tail = NULL;
328
329 spin_unlock(&device->io_lock);
330
331 while (pending) {
332
333 rmb();
334 /* we want to work on both lists, but do more bios on the
335 * sync list than the regular list
336 */
337 if ((num_run > 32 &&
338 pending_bios != &device->pending_sync_bios &&
339 device->pending_sync_bios.head) ||
340 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
341 device->pending_bios.head)) {
342 spin_lock(&device->io_lock);
343 requeue_list(pending_bios, pending, tail);
344 goto loop_lock;
345 }
346
347 cur = pending;
348 pending = pending->bi_next;
349 cur->bi_next = NULL;
350
351 if (atomic_dec_return(&fs_info->nr_async_bios) < limit &&
352 waitqueue_active(&fs_info->async_submit_wait))
353 wake_up(&fs_info->async_submit_wait);
354
355 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
356
357 /*
358 * if we're doing the sync list, record that our
359 * plug has some sync requests on it
360 *
361 * If we're doing the regular list and there are
362 * sync requests sitting around, unplug before
363 * we add more
364 */
365 if (pending_bios == &device->pending_sync_bios) {
366 sync_pending = 1;
367 } else if (sync_pending) {
368 blk_finish_plug(&plug);
369 blk_start_plug(&plug);
370 sync_pending = 0;
371 }
372
373 btrfsic_submit_bio(cur->bi_rw, cur);
374 num_run++;
375 batch_run++;
376 if (need_resched())
377 cond_resched();
378
379 /*
380 * we made progress, there is more work to do and the bdi
381 * is now congested. Back off and let other work structs
382 * run instead
383 */
384 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
385 fs_info->fs_devices->open_devices > 1) {
386 struct io_context *ioc;
387
388 ioc = current->io_context;
389
390 /*
391 * the main goal here is that we don't want to
392 * block if we're going to be able to submit
393 * more requests without blocking.
394 *
395 * This code does two great things, it pokes into
396 * the elevator code from a filesystem _and_
397 * it makes assumptions about how batching works.
398 */
399 if (ioc && ioc->nr_batch_requests > 0 &&
400 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
401 (last_waited == 0 ||
402 ioc->last_waited == last_waited)) {
403 /*
404 * we want to go through our batch of
405 * requests and stop. So, we copy out
406 * the ioc->last_waited time and test
407 * against it before looping
408 */
409 last_waited = ioc->last_waited;
410 if (need_resched())
411 cond_resched();
412 continue;
413 }
414 spin_lock(&device->io_lock);
415 requeue_list(pending_bios, pending, tail);
416 device->running_pending = 1;
417
418 spin_unlock(&device->io_lock);
419 btrfs_queue_work(fs_info->submit_workers,
420 &device->work);
421 goto done;
422 }
423 /* unplug every 64 requests just for good measure */
424 if (batch_run % 64 == 0) {
425 blk_finish_plug(&plug);
426 blk_start_plug(&plug);
427 sync_pending = 0;
428 }
429 }
430
431 cond_resched();
432 if (again)
433 goto loop;
434
435 spin_lock(&device->io_lock);
436 if (device->pending_bios.head || device->pending_sync_bios.head)
437 goto loop_lock;
438 spin_unlock(&device->io_lock);
439
440 done:
441 blk_finish_plug(&plug);
442 }
443
444 static void pending_bios_fn(struct btrfs_work *work)
445 {
446 struct btrfs_device *device;
447
448 device = container_of(work, struct btrfs_device, work);
449 run_scheduled_bios(device);
450 }
451
452 /*
453 * Add new device to list of registered devices
454 *
455 * Returns:
456 * 1 - first time device is seen
457 * 0 - device already known
458 * < 0 - error
459 */
460 static noinline int device_list_add(const char *path,
461 struct btrfs_super_block *disk_super,
462 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
463 {
464 struct btrfs_device *device;
465 struct btrfs_fs_devices *fs_devices;
466 struct rcu_string *name;
467 int ret = 0;
468 u64 found_transid = btrfs_super_generation(disk_super);
469
470 fs_devices = find_fsid(disk_super->fsid);
471 if (!fs_devices) {
472 fs_devices = alloc_fs_devices(disk_super->fsid);
473 if (IS_ERR(fs_devices))
474 return PTR_ERR(fs_devices);
475
476 list_add(&fs_devices->list, &fs_uuids);
477 fs_devices->latest_devid = devid;
478 fs_devices->latest_trans = found_transid;
479
480 device = NULL;
481 } else {
482 device = __find_device(&fs_devices->devices, devid,
483 disk_super->dev_item.uuid);
484 }
485 if (!device) {
486 if (fs_devices->opened)
487 return -EBUSY;
488
489 device = btrfs_alloc_device(NULL, &devid,
490 disk_super->dev_item.uuid);
491 if (IS_ERR(device)) {
492 /* we can safely leave the fs_devices entry around */
493 return PTR_ERR(device);
494 }
495
496 name = rcu_string_strdup(path, GFP_NOFS);
497 if (!name) {
498 kfree(device);
499 return -ENOMEM;
500 }
501 rcu_assign_pointer(device->name, name);
502
503 mutex_lock(&fs_devices->device_list_mutex);
504 list_add_rcu(&device->dev_list, &fs_devices->devices);
505 fs_devices->num_devices++;
506 mutex_unlock(&fs_devices->device_list_mutex);
507
508 ret = 1;
509 device->fs_devices = fs_devices;
510 } else if (!device->name || strcmp(device->name->str, path)) {
511 name = rcu_string_strdup(path, GFP_NOFS);
512 if (!name)
513 return -ENOMEM;
514 rcu_string_free(device->name);
515 rcu_assign_pointer(device->name, name);
516 if (device->missing) {
517 fs_devices->missing_devices--;
518 device->missing = 0;
519 }
520 }
521
522 if (found_transid > fs_devices->latest_trans) {
523 fs_devices->latest_devid = devid;
524 fs_devices->latest_trans = found_transid;
525 }
526 *fs_devices_ret = fs_devices;
527
528 return ret;
529 }
530
531 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
532 {
533 struct btrfs_fs_devices *fs_devices;
534 struct btrfs_device *device;
535 struct btrfs_device *orig_dev;
536
537 fs_devices = alloc_fs_devices(orig->fsid);
538 if (IS_ERR(fs_devices))
539 return fs_devices;
540
541 fs_devices->latest_devid = orig->latest_devid;
542 fs_devices->latest_trans = orig->latest_trans;
543 fs_devices->total_devices = orig->total_devices;
544
545 /* We have held the volume lock, it is safe to get the devices. */
546 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
547 struct rcu_string *name;
548
549 device = btrfs_alloc_device(NULL, &orig_dev->devid,
550 orig_dev->uuid);
551 if (IS_ERR(device))
552 goto error;
553
554 /*
555 * This is ok to do without rcu read locked because we hold the
556 * uuid mutex so nothing we touch in here is going to disappear.
557 */
558 if (orig_dev->name) {
559 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
560 if (!name) {
561 kfree(device);
562 goto error;
563 }
564 rcu_assign_pointer(device->name, name);
565 }
566
567 list_add(&device->dev_list, &fs_devices->devices);
568 device->fs_devices = fs_devices;
569 fs_devices->num_devices++;
570 }
571 return fs_devices;
572 error:
573 free_fs_devices(fs_devices);
574 return ERR_PTR(-ENOMEM);
575 }
576
577 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info,
578 struct btrfs_fs_devices *fs_devices, int step)
579 {
580 struct btrfs_device *device, *next;
581
582 struct block_device *latest_bdev = NULL;
583 u64 latest_devid = 0;
584 u64 latest_transid = 0;
585
586 mutex_lock(&uuid_mutex);
587 again:
588 /* This is the initialized path, it is safe to release the devices. */
589 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
590 if (device->in_fs_metadata) {
591 if (!device->is_tgtdev_for_dev_replace &&
592 (!latest_transid ||
593 device->generation > latest_transid)) {
594 latest_devid = device->devid;
595 latest_transid = device->generation;
596 latest_bdev = device->bdev;
597 }
598 continue;
599 }
600
601 if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
602 /*
603 * In the first step, keep the device which has
604 * the correct fsid and the devid that is used
605 * for the dev_replace procedure.
606 * In the second step, the dev_replace state is
607 * read from the device tree and it is known
608 * whether the procedure is really active or
609 * not, which means whether this device is
610 * used or whether it should be removed.
611 */
612 if (step == 0 || device->is_tgtdev_for_dev_replace) {
613 continue;
614 }
615 }
616 if (device->bdev) {
617 blkdev_put(device->bdev, device->mode);
618 device->bdev = NULL;
619 fs_devices->open_devices--;
620 }
621 if (device->writeable) {
622 list_del_init(&device->dev_alloc_list);
623 device->writeable = 0;
624 if (!device->is_tgtdev_for_dev_replace)
625 fs_devices->rw_devices--;
626 }
627 list_del_init(&device->dev_list);
628 fs_devices->num_devices--;
629 rcu_string_free(device->name);
630 kfree(device);
631 }
632
633 if (fs_devices->seed) {
634 fs_devices = fs_devices->seed;
635 goto again;
636 }
637
638 fs_devices->latest_bdev = latest_bdev;
639 fs_devices->latest_devid = latest_devid;
640 fs_devices->latest_trans = latest_transid;
641
642 mutex_unlock(&uuid_mutex);
643 }
644
645 static void __free_device(struct work_struct *work)
646 {
647 struct btrfs_device *device;
648
649 device = container_of(work, struct btrfs_device, rcu_work);
650
651 if (device->bdev)
652 blkdev_put(device->bdev, device->mode);
653
654 rcu_string_free(device->name);
655 kfree(device);
656 }
657
658 static void free_device(struct rcu_head *head)
659 {
660 struct btrfs_device *device;
661
662 device = container_of(head, struct btrfs_device, rcu);
663
664 INIT_WORK(&device->rcu_work, __free_device);
665 schedule_work(&device->rcu_work);
666 }
667
668 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
669 {
670 struct btrfs_device *device;
671
672 if (--fs_devices->opened > 0)
673 return 0;
674
675 mutex_lock(&fs_devices->device_list_mutex);
676 list_for_each_entry(device, &fs_devices->devices, dev_list) {
677 struct btrfs_device *new_device;
678 struct rcu_string *name;
679
680 if (device->bdev)
681 fs_devices->open_devices--;
682
683 if (device->writeable &&
684 device->devid != BTRFS_DEV_REPLACE_DEVID) {
685 list_del_init(&device->dev_alloc_list);
686 fs_devices->rw_devices--;
687 }
688
689 if (device->can_discard)
690 fs_devices->num_can_discard--;
691 if (device->missing)
692 fs_devices->missing_devices--;
693
694 new_device = btrfs_alloc_device(NULL, &device->devid,
695 device->uuid);
696 BUG_ON(IS_ERR(new_device)); /* -ENOMEM */
697
698 /* Safe because we are under uuid_mutex */
699 if (device->name) {
700 name = rcu_string_strdup(device->name->str, GFP_NOFS);
701 BUG_ON(!name); /* -ENOMEM */
702 rcu_assign_pointer(new_device->name, name);
703 }
704
705 list_replace_rcu(&device->dev_list, &new_device->dev_list);
706 new_device->fs_devices = device->fs_devices;
707
708 call_rcu(&device->rcu, free_device);
709 }
710 mutex_unlock(&fs_devices->device_list_mutex);
711
712 WARN_ON(fs_devices->open_devices);
713 WARN_ON(fs_devices->rw_devices);
714 fs_devices->opened = 0;
715 fs_devices->seeding = 0;
716
717 return 0;
718 }
719
720 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
721 {
722 struct btrfs_fs_devices *seed_devices = NULL;
723 int ret;
724
725 mutex_lock(&uuid_mutex);
726 ret = __btrfs_close_devices(fs_devices);
727 if (!fs_devices->opened) {
728 seed_devices = fs_devices->seed;
729 fs_devices->seed = NULL;
730 }
731 mutex_unlock(&uuid_mutex);
732
733 while (seed_devices) {
734 fs_devices = seed_devices;
735 seed_devices = fs_devices->seed;
736 __btrfs_close_devices(fs_devices);
737 free_fs_devices(fs_devices);
738 }
739 /*
740 * Wait for rcu kworkers under __btrfs_close_devices
741 * to finish all blkdev_puts so device is really
742 * free when umount is done.
743 */
744 rcu_barrier();
745 return ret;
746 }
747
748 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
749 fmode_t flags, void *holder)
750 {
751 struct request_queue *q;
752 struct block_device *bdev;
753 struct list_head *head = &fs_devices->devices;
754 struct btrfs_device *device;
755 struct block_device *latest_bdev = NULL;
756 struct buffer_head *bh;
757 struct btrfs_super_block *disk_super;
758 u64 latest_devid = 0;
759 u64 latest_transid = 0;
760 u64 devid;
761 int seeding = 1;
762 int ret = 0;
763
764 flags |= FMODE_EXCL;
765
766 list_for_each_entry(device, head, dev_list) {
767 if (device->bdev)
768 continue;
769 if (!device->name)
770 continue;
771
772 /* Just open everything we can; ignore failures here */
773 if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
774 &bdev, &bh))
775 continue;
776
777 disk_super = (struct btrfs_super_block *)bh->b_data;
778 devid = btrfs_stack_device_id(&disk_super->dev_item);
779 if (devid != device->devid)
780 goto error_brelse;
781
782 if (memcmp(device->uuid, disk_super->dev_item.uuid,
783 BTRFS_UUID_SIZE))
784 goto error_brelse;
785
786 device->generation = btrfs_super_generation(disk_super);
787 if (!latest_transid || device->generation > latest_transid) {
788 latest_devid = devid;
789 latest_transid = device->generation;
790 latest_bdev = bdev;
791 }
792
793 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
794 device->writeable = 0;
795 } else {
796 device->writeable = !bdev_read_only(bdev);
797 seeding = 0;
798 }
799
800 q = bdev_get_queue(bdev);
801 if (blk_queue_discard(q)) {
802 device->can_discard = 1;
803 fs_devices->num_can_discard++;
804 }
805
806 device->bdev = bdev;
807 device->in_fs_metadata = 0;
808 device->mode = flags;
809
810 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
811 fs_devices->rotating = 1;
812
813 fs_devices->open_devices++;
814 if (device->writeable &&
815 device->devid != BTRFS_DEV_REPLACE_DEVID) {
816 fs_devices->rw_devices++;
817 list_add(&device->dev_alloc_list,
818 &fs_devices->alloc_list);
819 }
820 brelse(bh);
821 continue;
822
823 error_brelse:
824 brelse(bh);
825 blkdev_put(bdev, flags);
826 continue;
827 }
828 if (fs_devices->open_devices == 0) {
829 ret = -EINVAL;
830 goto out;
831 }
832 fs_devices->seeding = seeding;
833 fs_devices->opened = 1;
834 fs_devices->latest_bdev = latest_bdev;
835 fs_devices->latest_devid = latest_devid;
836 fs_devices->latest_trans = latest_transid;
837 fs_devices->total_rw_bytes = 0;
838 out:
839 return ret;
840 }
841
842 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
843 fmode_t flags, void *holder)
844 {
845 int ret;
846
847 mutex_lock(&uuid_mutex);
848 if (fs_devices->opened) {
849 fs_devices->opened++;
850 ret = 0;
851 } else {
852 ret = __btrfs_open_devices(fs_devices, flags, holder);
853 }
854 mutex_unlock(&uuid_mutex);
855 return ret;
856 }
857
858 /*
859 * Look for a btrfs signature on a device. This may be called out of the mount path
860 * and we are not allowed to call set_blocksize during the scan. The superblock
861 * is read via pagecache
862 */
863 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
864 struct btrfs_fs_devices **fs_devices_ret)
865 {
866 struct btrfs_super_block *disk_super;
867 struct block_device *bdev;
868 struct page *page;
869 void *p;
870 int ret = -EINVAL;
871 u64 devid;
872 u64 transid;
873 u64 total_devices;
874 u64 bytenr;
875 pgoff_t index;
876
877 /*
878 * we would like to check all the supers, but that would make
879 * a btrfs mount succeed after a mkfs from a different FS.
880 * So, we need to add a special mount option to scan for
881 * later supers, using BTRFS_SUPER_MIRROR_MAX instead
882 */
883 bytenr = btrfs_sb_offset(0);
884 flags |= FMODE_EXCL;
885 mutex_lock(&uuid_mutex);
886
887 bdev = blkdev_get_by_path(path, flags, holder);
888
889 if (IS_ERR(bdev)) {
890 ret = PTR_ERR(bdev);
891 goto error;
892 }
893
894 /* make sure our super fits in the device */
895 if (bytenr + PAGE_CACHE_SIZE >= i_size_read(bdev->bd_inode))
896 goto error_bdev_put;
897
898 /* make sure our super fits in the page */
899 if (sizeof(*disk_super) > PAGE_CACHE_SIZE)
900 goto error_bdev_put;
901
902 /* make sure our super doesn't straddle pages on disk */
903 index = bytenr >> PAGE_CACHE_SHIFT;
904 if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_CACHE_SHIFT != index)
905 goto error_bdev_put;
906
907 /* pull in the page with our super */
908 page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
909 index, GFP_NOFS);
910
911 if (IS_ERR_OR_NULL(page))
912 goto error_bdev_put;
913
914 p = kmap(page);
915
916 /* align our pointer to the offset of the super block */
917 disk_super = p + (bytenr & ~PAGE_CACHE_MASK);
918
919 if (btrfs_super_bytenr(disk_super) != bytenr ||
920 btrfs_super_magic(disk_super) != BTRFS_MAGIC)
921 goto error_unmap;
922
923 devid = btrfs_stack_device_id(&disk_super->dev_item);
924 transid = btrfs_super_generation(disk_super);
925 total_devices = btrfs_super_num_devices(disk_super);
926
927 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
928 if (ret > 0) {
929 if (disk_super->label[0]) {
930 if (disk_super->label[BTRFS_LABEL_SIZE - 1])
931 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
932 printk(KERN_INFO "BTRFS: device label %s ", disk_super->label);
933 } else {
934 printk(KERN_INFO "BTRFS: device fsid %pU ", disk_super->fsid);
935 }
936
937 printk(KERN_CONT "devid %llu transid %llu %s\n", devid, transid, path);
938 ret = 0;
939 }
940 if (!ret && fs_devices_ret)
941 (*fs_devices_ret)->total_devices = total_devices;
942
943 error_unmap:
944 kunmap(page);
945 page_cache_release(page);
946
947 error_bdev_put:
948 blkdev_put(bdev, flags);
949 error:
950 mutex_unlock(&uuid_mutex);
951 return ret;
952 }
953
954 /* helper to account the used device space in the range */
955 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
956 u64 end, u64 *length)
957 {
958 struct btrfs_key key;
959 struct btrfs_root *root = device->dev_root;
960 struct btrfs_dev_extent *dev_extent;
961 struct btrfs_path *path;
962 u64 extent_end;
963 int ret;
964 int slot;
965 struct extent_buffer *l;
966
967 *length = 0;
968
969 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
970 return 0;
971
972 path = btrfs_alloc_path();
973 if (!path)
974 return -ENOMEM;
975 path->reada = 2;
976
977 key.objectid = device->devid;
978 key.offset = start;
979 key.type = BTRFS_DEV_EXTENT_KEY;
980
981 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
982 if (ret < 0)
983 goto out;
984 if (ret > 0) {
985 ret = btrfs_previous_item(root, path, key.objectid, key.type);
986 if (ret < 0)
987 goto out;
988 }
989
990 while (1) {
991 l = path->nodes[0];
992 slot = path->slots[0];
993 if (slot >= btrfs_header_nritems(l)) {
994 ret = btrfs_next_leaf(root, path);
995 if (ret == 0)
996 continue;
997 if (ret < 0)
998 goto out;
999
1000 break;
1001 }
1002 btrfs_item_key_to_cpu(l, &key, slot);
1003
1004 if (key.objectid < device->devid)
1005 goto next;
1006
1007 if (key.objectid > device->devid)
1008 break;
1009
1010 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
1011 goto next;
1012
1013 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1014 extent_end = key.offset + btrfs_dev_extent_length(l,
1015 dev_extent);
1016 if (key.offset <= start && extent_end > end) {
1017 *length = end - start + 1;
1018 break;
1019 } else if (key.offset <= start && extent_end > start)
1020 *length += extent_end - start;
1021 else if (key.offset > start && extent_end <= end)
1022 *length += extent_end - key.offset;
1023 else if (key.offset > start && key.offset <= end) {
1024 *length += end - key.offset + 1;
1025 break;
1026 } else if (key.offset > end)
1027 break;
1028
1029 next:
1030 path->slots[0]++;
1031 }
1032 ret = 0;
1033 out:
1034 btrfs_free_path(path);
1035 return ret;
1036 }
1037
1038 static int contains_pending_extent(struct btrfs_trans_handle *trans,
1039 struct btrfs_device *device,
1040 u64 *start, u64 len)
1041 {
1042 struct extent_map *em;
1043 int ret = 0;
1044
1045 list_for_each_entry(em, &trans->transaction->pending_chunks, list) {
1046 struct map_lookup *map;
1047 int i;
1048
1049 map = (struct map_lookup *)em->bdev;
1050 for (i = 0; i < map->num_stripes; i++) {
1051 if (map->stripes[i].dev != device)
1052 continue;
1053 if (map->stripes[i].physical >= *start + len ||
1054 map->stripes[i].physical + em->orig_block_len <=
1055 *start)
1056 continue;
1057 *start = map->stripes[i].physical +
1058 em->orig_block_len;
1059 ret = 1;
1060 }
1061 }
1062
1063 return ret;
1064 }
1065
1066
1067 /*
1068 * find_free_dev_extent - find free space in the specified device
1069 * @device: the device which we search the free space in
1070 * @num_bytes: the size of the free space that we need
1071 * @start: store the start of the free space.
1072 * @len: the size of the free space. that we find, or the size of the max
1073 * free space if we don't find suitable free space
1074 *
1075 * this uses a pretty simple search, the expectation is that it is
1076 * called very infrequently and that a given device has a small number
1077 * of extents
1078 *
1079 * @start is used to store the start of the free space if we find. But if we
1080 * don't find suitable free space, it will be used to store the start position
1081 * of the max free space.
1082 *
1083 * @len is used to store the size of the free space that we find.
1084 * But if we don't find suitable free space, it is used to store the size of
1085 * the max free space.
1086 */
1087 int find_free_dev_extent(struct btrfs_trans_handle *trans,
1088 struct btrfs_device *device, u64 num_bytes,
1089 u64 *start, u64 *len)
1090 {
1091 struct btrfs_key key;
1092 struct btrfs_root *root = device->dev_root;
1093 struct btrfs_dev_extent *dev_extent;
1094 struct btrfs_path *path;
1095 u64 hole_size;
1096 u64 max_hole_start;
1097 u64 max_hole_size;
1098 u64 extent_end;
1099 u64 search_start;
1100 u64 search_end = device->total_bytes;
1101 int ret;
1102 int slot;
1103 struct extent_buffer *l;
1104
1105 /* FIXME use last free of some kind */
1106
1107 /* we don't want to overwrite the superblock on the drive,
1108 * so we make sure to start at an offset of at least 1MB
1109 */
1110 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
1111
1112 path = btrfs_alloc_path();
1113 if (!path)
1114 return -ENOMEM;
1115 again:
1116 max_hole_start = search_start;
1117 max_hole_size = 0;
1118 hole_size = 0;
1119
1120 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
1121 ret = -ENOSPC;
1122 goto out;
1123 }
1124
1125 path->reada = 2;
1126 path->search_commit_root = 1;
1127 path->skip_locking = 1;
1128
1129 key.objectid = device->devid;
1130 key.offset = search_start;
1131 key.type = BTRFS_DEV_EXTENT_KEY;
1132
1133 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1134 if (ret < 0)
1135 goto out;
1136 if (ret > 0) {
1137 ret = btrfs_previous_item(root, path, key.objectid, key.type);
1138 if (ret < 0)
1139 goto out;
1140 }
1141
1142 while (1) {
1143 l = path->nodes[0];
1144 slot = path->slots[0];
1145 if (slot >= btrfs_header_nritems(l)) {
1146 ret = btrfs_next_leaf(root, path);
1147 if (ret == 0)
1148 continue;
1149 if (ret < 0)
1150 goto out;
1151
1152 break;
1153 }
1154 btrfs_item_key_to_cpu(l, &key, slot);
1155
1156 if (key.objectid < device->devid)
1157 goto next;
1158
1159 if (key.objectid > device->devid)
1160 break;
1161
1162 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
1163 goto next;
1164
1165 if (key.offset > search_start) {
1166 hole_size = key.offset - search_start;
1167
1168 /*
1169 * Have to check before we set max_hole_start, otherwise
1170 * we could end up sending back this offset anyway.
1171 */
1172 if (contains_pending_extent(trans, device,
1173 &search_start,
1174 hole_size))
1175 hole_size = 0;
1176
1177 if (hole_size > max_hole_size) {
1178 max_hole_start = search_start;
1179 max_hole_size = hole_size;
1180 }
1181
1182 /*
1183 * If this free space is greater than which we need,
1184 * it must be the max free space that we have found
1185 * until now, so max_hole_start must point to the start
1186 * of this free space and the length of this free space
1187 * is stored in max_hole_size. Thus, we return
1188 * max_hole_start and max_hole_size and go back to the
1189 * caller.
1190 */
1191 if (hole_size >= num_bytes) {
1192 ret = 0;
1193 goto out;
1194 }
1195 }
1196
1197 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1198 extent_end = key.offset + btrfs_dev_extent_length(l,
1199 dev_extent);
1200 if (extent_end > search_start)
1201 search_start = extent_end;
1202 next:
1203 path->slots[0]++;
1204 cond_resched();
1205 }
1206
1207 /*
1208 * At this point, search_start should be the end of
1209 * allocated dev extents, and when shrinking the device,
1210 * search_end may be smaller than search_start.
1211 */
1212 if (search_end > search_start)
1213 hole_size = search_end - search_start;
1214
1215 if (hole_size > max_hole_size) {
1216 max_hole_start = search_start;
1217 max_hole_size = hole_size;
1218 }
1219
1220 if (contains_pending_extent(trans, device, &search_start, hole_size)) {
1221 btrfs_release_path(path);
1222 goto again;
1223 }
1224
1225 /* See above. */
1226 if (hole_size < num_bytes)
1227 ret = -ENOSPC;
1228 else
1229 ret = 0;
1230
1231 out:
1232 btrfs_free_path(path);
1233 *start = max_hole_start;
1234 if (len)
1235 *len = max_hole_size;
1236 return ret;
1237 }
1238
1239 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1240 struct btrfs_device *device,
1241 u64 start)
1242 {
1243 int ret;
1244 struct btrfs_path *path;
1245 struct btrfs_root *root = device->dev_root;
1246 struct btrfs_key key;
1247 struct btrfs_key found_key;
1248 struct extent_buffer *leaf = NULL;
1249 struct btrfs_dev_extent *extent = NULL;
1250
1251 path = btrfs_alloc_path();
1252 if (!path)
1253 return -ENOMEM;
1254
1255 key.objectid = device->devid;
1256 key.offset = start;
1257 key.type = BTRFS_DEV_EXTENT_KEY;
1258 again:
1259 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1260 if (ret > 0) {
1261 ret = btrfs_previous_item(root, path, key.objectid,
1262 BTRFS_DEV_EXTENT_KEY);
1263 if (ret)
1264 goto out;
1265 leaf = path->nodes[0];
1266 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1267 extent = btrfs_item_ptr(leaf, path->slots[0],
1268 struct btrfs_dev_extent);
1269 BUG_ON(found_key.offset > start || found_key.offset +
1270 btrfs_dev_extent_length(leaf, extent) < start);
1271 key = found_key;
1272 btrfs_release_path(path);
1273 goto again;
1274 } else if (ret == 0) {
1275 leaf = path->nodes[0];
1276 extent = btrfs_item_ptr(leaf, path->slots[0],
1277 struct btrfs_dev_extent);
1278 } else {
1279 btrfs_error(root->fs_info, ret, "Slot search failed");
1280 goto out;
1281 }
1282
1283 if (device->bytes_used > 0) {
1284 u64 len = btrfs_dev_extent_length(leaf, extent);
1285 device->bytes_used -= len;
1286 spin_lock(&root->fs_info->free_chunk_lock);
1287 root->fs_info->free_chunk_space += len;
1288 spin_unlock(&root->fs_info->free_chunk_lock);
1289 }
1290 ret = btrfs_del_item(trans, root, path);
1291 if (ret) {
1292 btrfs_error(root->fs_info, ret,
1293 "Failed to remove dev extent item");
1294 }
1295 out:
1296 btrfs_free_path(path);
1297 return ret;
1298 }
1299
1300 static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1301 struct btrfs_device *device,
1302 u64 chunk_tree, u64 chunk_objectid,
1303 u64 chunk_offset, u64 start, u64 num_bytes)
1304 {
1305 int ret;
1306 struct btrfs_path *path;
1307 struct btrfs_root *root = device->dev_root;
1308 struct btrfs_dev_extent *extent;
1309 struct extent_buffer *leaf;
1310 struct btrfs_key key;
1311
1312 WARN_ON(!device->in_fs_metadata);
1313 WARN_ON(device->is_tgtdev_for_dev_replace);
1314 path = btrfs_alloc_path();
1315 if (!path)
1316 return -ENOMEM;
1317
1318 key.objectid = device->devid;
1319 key.offset = start;
1320 key.type = BTRFS_DEV_EXTENT_KEY;
1321 ret = btrfs_insert_empty_item(trans, root, path, &key,
1322 sizeof(*extent));
1323 if (ret)
1324 goto out;
1325
1326 leaf = path->nodes[0];
1327 extent = btrfs_item_ptr(leaf, path->slots[0],
1328 struct btrfs_dev_extent);
1329 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1330 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1331 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1332
1333 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1334 btrfs_dev_extent_chunk_tree_uuid(extent), BTRFS_UUID_SIZE);
1335
1336 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1337 btrfs_mark_buffer_dirty(leaf);
1338 out:
1339 btrfs_free_path(path);
1340 return ret;
1341 }
1342
1343 static u64 find_next_chunk(struct btrfs_fs_info *fs_info)
1344 {
1345 struct extent_map_tree *em_tree;
1346 struct extent_map *em;
1347 struct rb_node *n;
1348 u64 ret = 0;
1349
1350 em_tree = &fs_info->mapping_tree.map_tree;
1351 read_lock(&em_tree->lock);
1352 n = rb_last(&em_tree->map);
1353 if (n) {
1354 em = rb_entry(n, struct extent_map, rb_node);
1355 ret = em->start + em->len;
1356 }
1357 read_unlock(&em_tree->lock);
1358
1359 return ret;
1360 }
1361
1362 static noinline int find_next_devid(struct btrfs_fs_info *fs_info,
1363 u64 *devid_ret)
1364 {
1365 int ret;
1366 struct btrfs_key key;
1367 struct btrfs_key found_key;
1368 struct btrfs_path *path;
1369
1370 path = btrfs_alloc_path();
1371 if (!path)
1372 return -ENOMEM;
1373
1374 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1375 key.type = BTRFS_DEV_ITEM_KEY;
1376 key.offset = (u64)-1;
1377
1378 ret = btrfs_search_slot(NULL, fs_info->chunk_root, &key, path, 0, 0);
1379 if (ret < 0)
1380 goto error;
1381
1382 BUG_ON(ret == 0); /* Corruption */
1383
1384 ret = btrfs_previous_item(fs_info->chunk_root, path,
1385 BTRFS_DEV_ITEMS_OBJECTID,
1386 BTRFS_DEV_ITEM_KEY);
1387 if (ret) {
1388 *devid_ret = 1;
1389 } else {
1390 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1391 path->slots[0]);
1392 *devid_ret = found_key.offset + 1;
1393 }
1394 ret = 0;
1395 error:
1396 btrfs_free_path(path);
1397 return ret;
1398 }
1399
1400 /*
1401 * the device information is stored in the chunk root
1402 * the btrfs_device struct should be fully filled in
1403 */
1404 static int btrfs_add_device(struct btrfs_trans_handle *trans,
1405 struct btrfs_root *root,
1406 struct btrfs_device *device)
1407 {
1408 int ret;
1409 struct btrfs_path *path;
1410 struct btrfs_dev_item *dev_item;
1411 struct extent_buffer *leaf;
1412 struct btrfs_key key;
1413 unsigned long ptr;
1414
1415 root = root->fs_info->chunk_root;
1416
1417 path = btrfs_alloc_path();
1418 if (!path)
1419 return -ENOMEM;
1420
1421 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1422 key.type = BTRFS_DEV_ITEM_KEY;
1423 key.offset = device->devid;
1424
1425 ret = btrfs_insert_empty_item(trans, root, path, &key,
1426 sizeof(*dev_item));
1427 if (ret)
1428 goto out;
1429
1430 leaf = path->nodes[0];
1431 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1432
1433 btrfs_set_device_id(leaf, dev_item, device->devid);
1434 btrfs_set_device_generation(leaf, dev_item, 0);
1435 btrfs_set_device_type(leaf, dev_item, device->type);
1436 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1437 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1438 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1439 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
1440 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1441 btrfs_set_device_group(leaf, dev_item, 0);
1442 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1443 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1444 btrfs_set_device_start_offset(leaf, dev_item, 0);
1445
1446 ptr = btrfs_device_uuid(dev_item);
1447 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1448 ptr = btrfs_device_fsid(dev_item);
1449 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1450 btrfs_mark_buffer_dirty(leaf);
1451
1452 ret = 0;
1453 out:
1454 btrfs_free_path(path);
1455 return ret;
1456 }
1457
1458 /*
1459 * Function to update ctime/mtime for a given device path.
1460 * Mainly used for ctime/mtime based probe like libblkid.
1461 */
1462 static void update_dev_time(char *path_name)
1463 {
1464 struct file *filp;
1465
1466 filp = filp_open(path_name, O_RDWR, 0);
1467 if (!filp)
1468 return;
1469 file_update_time(filp);
1470 filp_close(filp, NULL);
1471 return;
1472 }
1473
1474 static int btrfs_rm_dev_item(struct btrfs_root *root,
1475 struct btrfs_device *device)
1476 {
1477 int ret;
1478 struct btrfs_path *path;
1479 struct btrfs_key key;
1480 struct btrfs_trans_handle *trans;
1481
1482 root = root->fs_info->chunk_root;
1483
1484 path = btrfs_alloc_path();
1485 if (!path)
1486 return -ENOMEM;
1487
1488 trans = btrfs_start_transaction(root, 0);
1489 if (IS_ERR(trans)) {
1490 btrfs_free_path(path);
1491 return PTR_ERR(trans);
1492 }
1493 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1494 key.type = BTRFS_DEV_ITEM_KEY;
1495 key.offset = device->devid;
1496 lock_chunks(root);
1497
1498 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1499 if (ret < 0)
1500 goto out;
1501
1502 if (ret > 0) {
1503 ret = -ENOENT;
1504 goto out;
1505 }
1506
1507 ret = btrfs_del_item(trans, root, path);
1508 if (ret)
1509 goto out;
1510 out:
1511 btrfs_free_path(path);
1512 unlock_chunks(root);
1513 btrfs_commit_transaction(trans, root);
1514 return ret;
1515 }
1516
1517 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1518 {
1519 struct btrfs_device *device;
1520 struct btrfs_device *next_device;
1521 struct block_device *bdev;
1522 struct buffer_head *bh = NULL;
1523 struct btrfs_super_block *disk_super;
1524 struct btrfs_fs_devices *cur_devices;
1525 u64 all_avail;
1526 u64 devid;
1527 u64 num_devices;
1528 u8 *dev_uuid;
1529 unsigned seq;
1530 int ret = 0;
1531 bool clear_super = false;
1532
1533 mutex_lock(&uuid_mutex);
1534
1535 do {
1536 seq = read_seqbegin(&root->fs_info->profiles_lock);
1537
1538 all_avail = root->fs_info->avail_data_alloc_bits |
1539 root->fs_info->avail_system_alloc_bits |
1540 root->fs_info->avail_metadata_alloc_bits;
1541 } while (read_seqretry(&root->fs_info->profiles_lock, seq));
1542
1543 num_devices = root->fs_info->fs_devices->num_devices;
1544 btrfs_dev_replace_lock(&root->fs_info->dev_replace);
1545 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1546 WARN_ON(num_devices < 1);
1547 num_devices--;
1548 }
1549 btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
1550
1551 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
1552 ret = BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
1553 goto out;
1554 }
1555
1556 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
1557 ret = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
1558 goto out;
1559 }
1560
1561 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
1562 root->fs_info->fs_devices->rw_devices <= 2) {
1563 ret = BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
1564 goto out;
1565 }
1566 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
1567 root->fs_info->fs_devices->rw_devices <= 3) {
1568 ret = BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
1569 goto out;
1570 }
1571
1572 if (strcmp(device_path, "missing") == 0) {
1573 struct list_head *devices;
1574 struct btrfs_device *tmp;
1575
1576 device = NULL;
1577 devices = &root->fs_info->fs_devices->devices;
1578 /*
1579 * It is safe to read the devices since the volume_mutex
1580 * is held.
1581 */
1582 list_for_each_entry(tmp, devices, dev_list) {
1583 if (tmp->in_fs_metadata &&
1584 !tmp->is_tgtdev_for_dev_replace &&
1585 !tmp->bdev) {
1586 device = tmp;
1587 break;
1588 }
1589 }
1590 bdev = NULL;
1591 bh = NULL;
1592 disk_super = NULL;
1593 if (!device) {
1594 ret = BTRFS_ERROR_DEV_MISSING_NOT_FOUND;
1595 goto out;
1596 }
1597 } else {
1598 ret = btrfs_get_bdev_and_sb(device_path,
1599 FMODE_WRITE | FMODE_EXCL,
1600 root->fs_info->bdev_holder, 0,
1601 &bdev, &bh);
1602 if (ret)
1603 goto out;
1604 disk_super = (struct btrfs_super_block *)bh->b_data;
1605 devid = btrfs_stack_device_id(&disk_super->dev_item);
1606 dev_uuid = disk_super->dev_item.uuid;
1607 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1608 disk_super->fsid);
1609 if (!device) {
1610 ret = -ENOENT;
1611 goto error_brelse;
1612 }
1613 }
1614
1615 if (device->is_tgtdev_for_dev_replace) {
1616 ret = BTRFS_ERROR_DEV_TGT_REPLACE;
1617 goto error_brelse;
1618 }
1619
1620 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1621 ret = BTRFS_ERROR_DEV_ONLY_WRITABLE;
1622 goto error_brelse;
1623 }
1624
1625 if (device->writeable) {
1626 lock_chunks(root);
1627 list_del_init(&device->dev_alloc_list);
1628 unlock_chunks(root);
1629 root->fs_info->fs_devices->rw_devices--;
1630 clear_super = true;
1631 }
1632
1633 mutex_unlock(&uuid_mutex);
1634 ret = btrfs_shrink_device(device, 0);
1635 mutex_lock(&uuid_mutex);
1636 if (ret)
1637 goto error_undo;
1638
1639 /*
1640 * TODO: the superblock still includes this device in its num_devices
1641 * counter although write_all_supers() is not locked out. This
1642 * could give a filesystem state which requires a degraded mount.
1643 */
1644 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1645 if (ret)
1646 goto error_undo;
1647
1648 spin_lock(&root->fs_info->free_chunk_lock);
1649 root->fs_info->free_chunk_space = device->total_bytes -
1650 device->bytes_used;
1651 spin_unlock(&root->fs_info->free_chunk_lock);
1652
1653 device->in_fs_metadata = 0;
1654 btrfs_scrub_cancel_dev(root->fs_info, device);
1655
1656 /*
1657 * the device list mutex makes sure that we don't change
1658 * the device list while someone else is writing out all
1659 * the device supers. Whoever is writing all supers, should
1660 * lock the device list mutex before getting the number of
1661 * devices in the super block (super_copy). Conversely,
1662 * whoever updates the number of devices in the super block
1663 * (super_copy) should hold the device list mutex.
1664 */
1665
1666 cur_devices = device->fs_devices;
1667 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1668 list_del_rcu(&device->dev_list);
1669
1670 device->fs_devices->num_devices--;
1671 device->fs_devices->total_devices--;
1672
1673 if (device->missing)
1674 root->fs_info->fs_devices->missing_devices--;
1675
1676 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1677 struct btrfs_device, dev_list);
1678 if (device->bdev == root->fs_info->sb->s_bdev)
1679 root->fs_info->sb->s_bdev = next_device->bdev;
1680 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1681 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1682
1683 if (device->bdev) {
1684 device->fs_devices->open_devices--;
1685 /* remove sysfs entry */
1686 btrfs_kobj_rm_device(root->fs_info, device);
1687 }
1688
1689 call_rcu(&device->rcu, free_device);
1690
1691 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1692 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1693 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1694
1695 if (cur_devices->open_devices == 0) {
1696 struct btrfs_fs_devices *fs_devices;
1697 fs_devices = root->fs_info->fs_devices;
1698 while (fs_devices) {
1699 if (fs_devices->seed == cur_devices) {
1700 fs_devices->seed = cur_devices->seed;
1701 break;
1702 }
1703 fs_devices = fs_devices->seed;
1704 }
1705 cur_devices->seed = NULL;
1706 lock_chunks(root);
1707 __btrfs_close_devices(cur_devices);
1708 unlock_chunks(root);
1709 free_fs_devices(cur_devices);
1710 }
1711
1712 root->fs_info->num_tolerated_disk_barrier_failures =
1713 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1714
1715 /*
1716 * at this point, the device is zero sized. We want to
1717 * remove it from the devices list and zero out the old super
1718 */
1719 if (clear_super && disk_super) {
1720 u64 bytenr;
1721 int i;
1722
1723 /* make sure this device isn't detected as part of
1724 * the FS anymore
1725 */
1726 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1727 set_buffer_dirty(bh);
1728 sync_dirty_buffer(bh);
1729
1730 /* clear the mirror copies of super block on the disk
1731 * being removed, 0th copy is been taken care above and
1732 * the below would take of the rest
1733 */
1734 for (i = 1; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1735 bytenr = btrfs_sb_offset(i);
1736 if (bytenr + BTRFS_SUPER_INFO_SIZE >=
1737 i_size_read(bdev->bd_inode))
1738 break;
1739
1740 brelse(bh);
1741 bh = __bread(bdev, bytenr / 4096,
1742 BTRFS_SUPER_INFO_SIZE);
1743 if (!bh)
1744 continue;
1745
1746 disk_super = (struct btrfs_super_block *)bh->b_data;
1747
1748 if (btrfs_super_bytenr(disk_super) != bytenr ||
1749 btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
1750 continue;
1751 }
1752 memset(&disk_super->magic, 0,
1753 sizeof(disk_super->magic));
1754 set_buffer_dirty(bh);
1755 sync_dirty_buffer(bh);
1756 }
1757 }
1758
1759 ret = 0;
1760
1761 if (bdev) {
1762 /* Notify udev that device has changed */
1763 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
1764
1765 /* Update ctime/mtime for device path for libblkid */
1766 update_dev_time(device_path);
1767 }
1768
1769 error_brelse:
1770 brelse(bh);
1771 if (bdev)
1772 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1773 out:
1774 mutex_unlock(&uuid_mutex);
1775 return ret;
1776 error_undo:
1777 if (device->writeable) {
1778 lock_chunks(root);
1779 list_add(&device->dev_alloc_list,
1780 &root->fs_info->fs_devices->alloc_list);
1781 unlock_chunks(root);
1782 root->fs_info->fs_devices->rw_devices++;
1783 }
1784 goto error_brelse;
1785 }
1786
1787 void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info,
1788 struct btrfs_device *srcdev)
1789 {
1790 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1791
1792 list_del_rcu(&srcdev->dev_list);
1793 list_del_rcu(&srcdev->dev_alloc_list);
1794 fs_info->fs_devices->num_devices--;
1795 if (srcdev->missing) {
1796 fs_info->fs_devices->missing_devices--;
1797 fs_info->fs_devices->rw_devices++;
1798 }
1799 if (srcdev->can_discard)
1800 fs_info->fs_devices->num_can_discard--;
1801 if (srcdev->bdev) {
1802 fs_info->fs_devices->open_devices--;
1803
1804 /* zero out the old super */
1805 btrfs_scratch_superblock(srcdev);
1806 }
1807
1808 call_rcu(&srcdev->rcu, free_device);
1809 }
1810
1811 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
1812 struct btrfs_device *tgtdev)
1813 {
1814 struct btrfs_device *next_device;
1815
1816 WARN_ON(!tgtdev);
1817 mutex_lock(&fs_info->fs_devices->device_list_mutex);
1818 if (tgtdev->bdev) {
1819 btrfs_scratch_superblock(tgtdev);
1820 fs_info->fs_devices->open_devices--;
1821 }
1822 fs_info->fs_devices->num_devices--;
1823 if (tgtdev->can_discard)
1824 fs_info->fs_devices->num_can_discard++;
1825
1826 next_device = list_entry(fs_info->fs_devices->devices.next,
1827 struct btrfs_device, dev_list);
1828 if (tgtdev->bdev == fs_info->sb->s_bdev)
1829 fs_info->sb->s_bdev = next_device->bdev;
1830 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
1831 fs_info->fs_devices->latest_bdev = next_device->bdev;
1832 list_del_rcu(&tgtdev->dev_list);
1833
1834 call_rcu(&tgtdev->rcu, free_device);
1835
1836 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
1837 }
1838
1839 static int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
1840 struct btrfs_device **device)
1841 {
1842 int ret = 0;
1843 struct btrfs_super_block *disk_super;
1844 u64 devid;
1845 u8 *dev_uuid;
1846 struct block_device *bdev;
1847 struct buffer_head *bh;
1848
1849 *device = NULL;
1850 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ,
1851 root->fs_info->bdev_holder, 0, &bdev, &bh);
1852 if (ret)
1853 return ret;
1854 disk_super = (struct btrfs_super_block *)bh->b_data;
1855 devid = btrfs_stack_device_id(&disk_super->dev_item);
1856 dev_uuid = disk_super->dev_item.uuid;
1857 *device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1858 disk_super->fsid);
1859 brelse(bh);
1860 if (!*device)
1861 ret = -ENOENT;
1862 blkdev_put(bdev, FMODE_READ);
1863 return ret;
1864 }
1865
1866 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
1867 char *device_path,
1868 struct btrfs_device **device)
1869 {
1870 *device = NULL;
1871 if (strcmp(device_path, "missing") == 0) {
1872 struct list_head *devices;
1873 struct btrfs_device *tmp;
1874
1875 devices = &root->fs_info->fs_devices->devices;
1876 /*
1877 * It is safe to read the devices since the volume_mutex
1878 * is held by the caller.
1879 */
1880 list_for_each_entry(tmp, devices, dev_list) {
1881 if (tmp->in_fs_metadata && !tmp->bdev) {
1882 *device = tmp;
1883 break;
1884 }
1885 }
1886
1887 if (!*device) {
1888 btrfs_err(root->fs_info, "no missing device found");
1889 return -ENOENT;
1890 }
1891
1892 return 0;
1893 } else {
1894 return btrfs_find_device_by_path(root, device_path, device);
1895 }
1896 }
1897
1898 /*
1899 * does all the dirty work required for changing file system's UUID.
1900 */
1901 static int btrfs_prepare_sprout(struct btrfs_root *root)
1902 {
1903 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1904 struct btrfs_fs_devices *old_devices;
1905 struct btrfs_fs_devices *seed_devices;
1906 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
1907 struct btrfs_device *device;
1908 u64 super_flags;
1909
1910 BUG_ON(!mutex_is_locked(&uuid_mutex));
1911 if (!fs_devices->seeding)
1912 return -EINVAL;
1913
1914 seed_devices = __alloc_fs_devices();
1915 if (IS_ERR(seed_devices))
1916 return PTR_ERR(seed_devices);
1917
1918 old_devices = clone_fs_devices(fs_devices);
1919 if (IS_ERR(old_devices)) {
1920 kfree(seed_devices);
1921 return PTR_ERR(old_devices);
1922 }
1923
1924 list_add(&old_devices->list, &fs_uuids);
1925
1926 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1927 seed_devices->opened = 1;
1928 INIT_LIST_HEAD(&seed_devices->devices);
1929 INIT_LIST_HEAD(&seed_devices->alloc_list);
1930 mutex_init(&seed_devices->device_list_mutex);
1931
1932 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1933 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
1934 synchronize_rcu);
1935
1936 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1937 list_for_each_entry(device, &seed_devices->devices, dev_list) {
1938 device->fs_devices = seed_devices;
1939 }
1940
1941 fs_devices->seeding = 0;
1942 fs_devices->num_devices = 0;
1943 fs_devices->open_devices = 0;
1944 fs_devices->seed = seed_devices;
1945
1946 generate_random_uuid(fs_devices->fsid);
1947 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1948 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1949 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1950
1951 super_flags = btrfs_super_flags(disk_super) &
1952 ~BTRFS_SUPER_FLAG_SEEDING;
1953 btrfs_set_super_flags(disk_super, super_flags);
1954
1955 return 0;
1956 }
1957
1958 /*
1959 * strore the expected generation for seed devices in device items.
1960 */
1961 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
1962 struct btrfs_root *root)
1963 {
1964 struct btrfs_path *path;
1965 struct extent_buffer *leaf;
1966 struct btrfs_dev_item *dev_item;
1967 struct btrfs_device *device;
1968 struct btrfs_key key;
1969 u8 fs_uuid[BTRFS_UUID_SIZE];
1970 u8 dev_uuid[BTRFS_UUID_SIZE];
1971 u64 devid;
1972 int ret;
1973
1974 path = btrfs_alloc_path();
1975 if (!path)
1976 return -ENOMEM;
1977
1978 root = root->fs_info->chunk_root;
1979 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1980 key.offset = 0;
1981 key.type = BTRFS_DEV_ITEM_KEY;
1982
1983 while (1) {
1984 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1985 if (ret < 0)
1986 goto error;
1987
1988 leaf = path->nodes[0];
1989 next_slot:
1990 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1991 ret = btrfs_next_leaf(root, path);
1992 if (ret > 0)
1993 break;
1994 if (ret < 0)
1995 goto error;
1996 leaf = path->nodes[0];
1997 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1998 btrfs_release_path(path);
1999 continue;
2000 }
2001
2002 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
2003 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
2004 key.type != BTRFS_DEV_ITEM_KEY)
2005 break;
2006
2007 dev_item = btrfs_item_ptr(leaf, path->slots[0],
2008 struct btrfs_dev_item);
2009 devid = btrfs_device_id(leaf, dev_item);
2010 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
2011 BTRFS_UUID_SIZE);
2012 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
2013 BTRFS_UUID_SIZE);
2014 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
2015 fs_uuid);
2016 BUG_ON(!device); /* Logic error */
2017
2018 if (device->fs_devices->seeding) {
2019 btrfs_set_device_generation(leaf, dev_item,
2020 device->generation);
2021 btrfs_mark_buffer_dirty(leaf);
2022 }
2023
2024 path->slots[0]++;
2025 goto next_slot;
2026 }
2027 ret = 0;
2028 error:
2029 btrfs_free_path(path);
2030 return ret;
2031 }
2032
2033 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
2034 {
2035 struct request_queue *q;
2036 struct btrfs_trans_handle *trans;
2037 struct btrfs_device *device;
2038 struct block_device *bdev;
2039 struct list_head *devices;
2040 struct super_block *sb = root->fs_info->sb;
2041 struct rcu_string *name;
2042 u64 total_bytes;
2043 int seeding_dev = 0;
2044 int ret = 0;
2045
2046 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
2047 return -EROFS;
2048
2049 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2050 root->fs_info->bdev_holder);
2051 if (IS_ERR(bdev))
2052 return PTR_ERR(bdev);
2053
2054 if (root->fs_info->fs_devices->seeding) {
2055 seeding_dev = 1;
2056 down_write(&sb->s_umount);
2057 mutex_lock(&uuid_mutex);
2058 }
2059
2060 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2061
2062 devices = &root->fs_info->fs_devices->devices;
2063
2064 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2065 list_for_each_entry(device, devices, dev_list) {
2066 if (device->bdev == bdev) {
2067 ret = -EEXIST;
2068 mutex_unlock(
2069 &root->fs_info->fs_devices->device_list_mutex);
2070 goto error;
2071 }
2072 }
2073 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2074
2075 device = btrfs_alloc_device(root->fs_info, NULL, NULL);
2076 if (IS_ERR(device)) {
2077 /* we can safely leave the fs_devices entry around */
2078 ret = PTR_ERR(device);
2079 goto error;
2080 }
2081
2082 name = rcu_string_strdup(device_path, GFP_NOFS);
2083 if (!name) {
2084 kfree(device);
2085 ret = -ENOMEM;
2086 goto error;
2087 }
2088 rcu_assign_pointer(device->name, name);
2089
2090 trans = btrfs_start_transaction(root, 0);
2091 if (IS_ERR(trans)) {
2092 rcu_string_free(device->name);
2093 kfree(device);
2094 ret = PTR_ERR(trans);
2095 goto error;
2096 }
2097
2098 lock_chunks(root);
2099
2100 q = bdev_get_queue(bdev);
2101 if (blk_queue_discard(q))
2102 device->can_discard = 1;
2103 device->writeable = 1;
2104 device->generation = trans->transid;
2105 device->io_width = root->sectorsize;
2106 device->io_align = root->sectorsize;
2107 device->sector_size = root->sectorsize;
2108 device->total_bytes = i_size_read(bdev->bd_inode);
2109 device->disk_total_bytes = device->total_bytes;
2110 device->dev_root = root->fs_info->dev_root;
2111 device->bdev = bdev;
2112 device->in_fs_metadata = 1;
2113 device->is_tgtdev_for_dev_replace = 0;
2114 device->mode = FMODE_EXCL;
2115 device->dev_stats_valid = 1;
2116 set_blocksize(device->bdev, 4096);
2117
2118 if (seeding_dev) {
2119 sb->s_flags &= ~MS_RDONLY;
2120 ret = btrfs_prepare_sprout(root);
2121 BUG_ON(ret); /* -ENOMEM */
2122 }
2123
2124 device->fs_devices = root->fs_info->fs_devices;
2125
2126 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2127 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
2128 list_add(&device->dev_alloc_list,
2129 &root->fs_info->fs_devices->alloc_list);
2130 root->fs_info->fs_devices->num_devices++;
2131 root->fs_info->fs_devices->open_devices++;
2132 root->fs_info->fs_devices->rw_devices++;
2133 root->fs_info->fs_devices->total_devices++;
2134 if (device->can_discard)
2135 root->fs_info->fs_devices->num_can_discard++;
2136 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
2137
2138 spin_lock(&root->fs_info->free_chunk_lock);
2139 root->fs_info->free_chunk_space += device->total_bytes;
2140 spin_unlock(&root->fs_info->free_chunk_lock);
2141
2142 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
2143 root->fs_info->fs_devices->rotating = 1;
2144
2145 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
2146 btrfs_set_super_total_bytes(root->fs_info->super_copy,
2147 total_bytes + device->total_bytes);
2148
2149 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy);
2150 btrfs_set_super_num_devices(root->fs_info->super_copy,
2151 total_bytes + 1);
2152
2153 /* add sysfs device entry */
2154 btrfs_kobj_add_device(root->fs_info, device);
2155
2156 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2157
2158 if (seeding_dev) {
2159 char fsid_buf[BTRFS_UUID_UNPARSED_SIZE];
2160 ret = init_first_rw_device(trans, root, device);
2161 if (ret) {
2162 btrfs_abort_transaction(trans, root, ret);
2163 goto error_trans;
2164 }
2165 ret = btrfs_finish_sprout(trans, root);
2166 if (ret) {
2167 btrfs_abort_transaction(trans, root, ret);
2168 goto error_trans;
2169 }
2170
2171 /* Sprouting would change fsid of the mounted root,
2172 * so rename the fsid on the sysfs
2173 */
2174 snprintf(fsid_buf, BTRFS_UUID_UNPARSED_SIZE, "%pU",
2175 root->fs_info->fsid);
2176 if (kobject_rename(&root->fs_info->super_kobj, fsid_buf))
2177 goto error_trans;
2178 } else {
2179 ret = btrfs_add_device(trans, root, device);
2180 if (ret) {
2181 btrfs_abort_transaction(trans, root, ret);
2182 goto error_trans;
2183 }
2184 }
2185
2186 /*
2187 * we've got more storage, clear any full flags on the space
2188 * infos
2189 */
2190 btrfs_clear_space_info_full(root->fs_info);
2191
2192 unlock_chunks(root);
2193 root->fs_info->num_tolerated_disk_barrier_failures =
2194 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2195 ret = btrfs_commit_transaction(trans, root);
2196
2197 if (seeding_dev) {
2198 mutex_unlock(&uuid_mutex);
2199 up_write(&sb->s_umount);
2200
2201 if (ret) /* transaction commit */
2202 return ret;
2203
2204 ret = btrfs_relocate_sys_chunks(root);
2205 if (ret < 0)
2206 btrfs_error(root->fs_info, ret,
2207 "Failed to relocate sys chunks after "
2208 "device initialization. This can be fixed "
2209 "using the \"btrfs balance\" command.");
2210 trans = btrfs_attach_transaction(root);
2211 if (IS_ERR(trans)) {
2212 if (PTR_ERR(trans) == -ENOENT)
2213 return 0;
2214 return PTR_ERR(trans);
2215 }
2216 ret = btrfs_commit_transaction(trans, root);
2217 }
2218
2219 /* Update ctime/mtime for libblkid */
2220 update_dev_time(device_path);
2221 return ret;
2222
2223 error_trans:
2224 unlock_chunks(root);
2225 btrfs_end_transaction(trans, root);
2226 rcu_string_free(device->name);
2227 btrfs_kobj_rm_device(root->fs_info, device);
2228 kfree(device);
2229 error:
2230 blkdev_put(bdev, FMODE_EXCL);
2231 if (seeding_dev) {
2232 mutex_unlock(&uuid_mutex);
2233 up_write(&sb->s_umount);
2234 }
2235 return ret;
2236 }
2237
2238 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2239 struct btrfs_device **device_out)
2240 {
2241 struct request_queue *q;
2242 struct btrfs_device *device;
2243 struct block_device *bdev;
2244 struct btrfs_fs_info *fs_info = root->fs_info;
2245 struct list_head *devices;
2246 struct rcu_string *name;
2247 u64 devid = BTRFS_DEV_REPLACE_DEVID;
2248 int ret = 0;
2249
2250 *device_out = NULL;
2251 if (fs_info->fs_devices->seeding)
2252 return -EINVAL;
2253
2254 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2255 fs_info->bdev_holder);
2256 if (IS_ERR(bdev))
2257 return PTR_ERR(bdev);
2258
2259 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2260
2261 devices = &fs_info->fs_devices->devices;
2262 list_for_each_entry(device, devices, dev_list) {
2263 if (device->bdev == bdev) {
2264 ret = -EEXIST;
2265 goto error;
2266 }
2267 }
2268
2269 device = btrfs_alloc_device(NULL, &devid, NULL);
2270 if (IS_ERR(device)) {
2271 ret = PTR_ERR(device);
2272 goto error;
2273 }
2274
2275 name = rcu_string_strdup(device_path, GFP_NOFS);
2276 if (!name) {
2277 kfree(device);
2278 ret = -ENOMEM;
2279 goto error;
2280 }
2281 rcu_assign_pointer(device->name, name);
2282
2283 q = bdev_get_queue(bdev);
2284 if (blk_queue_discard(q))
2285 device->can_discard = 1;
2286 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2287 device->writeable = 1;
2288 device->generation = 0;
2289 device->io_width = root->sectorsize;
2290 device->io_align = root->sectorsize;
2291 device->sector_size = root->sectorsize;
2292 device->total_bytes = i_size_read(bdev->bd_inode);
2293 device->disk_total_bytes = device->total_bytes;
2294 device->dev_root = fs_info->dev_root;
2295 device->bdev = bdev;
2296 device->in_fs_metadata = 1;
2297 device->is_tgtdev_for_dev_replace = 1;
2298 device->mode = FMODE_EXCL;
2299 device->dev_stats_valid = 1;
2300 set_blocksize(device->bdev, 4096);
2301 device->fs_devices = fs_info->fs_devices;
2302 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2303 fs_info->fs_devices->num_devices++;
2304 fs_info->fs_devices->open_devices++;
2305 if (device->can_discard)
2306 fs_info->fs_devices->num_can_discard++;
2307 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2308
2309 *device_out = device;
2310 return ret;
2311
2312 error:
2313 blkdev_put(bdev, FMODE_EXCL);
2314 return ret;
2315 }
2316
2317 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2318 struct btrfs_device *tgtdev)
2319 {
2320 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2321 tgtdev->io_width = fs_info->dev_root->sectorsize;
2322 tgtdev->io_align = fs_info->dev_root->sectorsize;
2323 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2324 tgtdev->dev_root = fs_info->dev_root;
2325 tgtdev->in_fs_metadata = 1;
2326 }
2327
2328 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2329 struct btrfs_device *device)
2330 {
2331 int ret;
2332 struct btrfs_path *path;
2333 struct btrfs_root *root;
2334 struct btrfs_dev_item *dev_item;
2335 struct extent_buffer *leaf;
2336 struct btrfs_key key;
2337
2338 root = device->dev_root->fs_info->chunk_root;
2339
2340 path = btrfs_alloc_path();
2341 if (!path)
2342 return -ENOMEM;
2343
2344 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2345 key.type = BTRFS_DEV_ITEM_KEY;
2346 key.offset = device->devid;
2347
2348 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2349 if (ret < 0)
2350 goto out;
2351
2352 if (ret > 0) {
2353 ret = -ENOENT;
2354 goto out;
2355 }
2356
2357 leaf = path->nodes[0];
2358 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2359
2360 btrfs_set_device_id(leaf, dev_item, device->devid);
2361 btrfs_set_device_type(leaf, dev_item, device->type);
2362 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2363 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2364 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2365 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes);
2366 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
2367 btrfs_mark_buffer_dirty(leaf);
2368
2369 out:
2370 btrfs_free_path(path);
2371 return ret;
2372 }
2373
2374 static int __btrfs_grow_device(struct btrfs_trans_handle *trans,
2375 struct btrfs_device *device, u64 new_size)
2376 {
2377 struct btrfs_super_block *super_copy =
2378 device->dev_root->fs_info->super_copy;
2379 u64 old_total = btrfs_super_total_bytes(super_copy);
2380 u64 diff = new_size - device->total_bytes;
2381
2382 if (!device->writeable)
2383 return -EACCES;
2384 if (new_size <= device->total_bytes ||
2385 device->is_tgtdev_for_dev_replace)
2386 return -EINVAL;
2387
2388 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2389 device->fs_devices->total_rw_bytes += diff;
2390
2391 device->total_bytes = new_size;
2392 device->disk_total_bytes = new_size;
2393 btrfs_clear_space_info_full(device->dev_root->fs_info);
2394
2395 return btrfs_update_device(trans, device);
2396 }
2397
2398 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2399 struct btrfs_device *device, u64 new_size)
2400 {
2401 int ret;
2402 lock_chunks(device->dev_root);
2403 ret = __btrfs_grow_device(trans, device, new_size);
2404 unlock_chunks(device->dev_root);
2405 return ret;
2406 }
2407
2408 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2409 struct btrfs_root *root,
2410 u64 chunk_tree, u64 chunk_objectid,
2411 u64 chunk_offset)
2412 {
2413 int ret;
2414 struct btrfs_path *path;
2415 struct btrfs_key key;
2416
2417 root = root->fs_info->chunk_root;
2418 path = btrfs_alloc_path();
2419 if (!path)
2420 return -ENOMEM;
2421
2422 key.objectid = chunk_objectid;
2423 key.offset = chunk_offset;
2424 key.type = BTRFS_CHUNK_ITEM_KEY;
2425
2426 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2427 if (ret < 0)
2428 goto out;
2429 else if (ret > 0) { /* Logic error or corruption */
2430 btrfs_error(root->fs_info, -ENOENT,
2431 "Failed lookup while freeing chunk.");
2432 ret = -ENOENT;
2433 goto out;
2434 }
2435
2436 ret = btrfs_del_item(trans, root, path);
2437 if (ret < 0)
2438 btrfs_error(root->fs_info, ret,
2439 "Failed to delete chunk item.");
2440 out:
2441 btrfs_free_path(path);
2442 return ret;
2443 }
2444
2445 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2446 chunk_offset)
2447 {
2448 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2449 struct btrfs_disk_key *disk_key;
2450 struct btrfs_chunk *chunk;
2451 u8 *ptr;
2452 int ret = 0;
2453 u32 num_stripes;
2454 u32 array_size;
2455 u32 len = 0;
2456 u32 cur;
2457 struct btrfs_key key;
2458
2459 array_size = btrfs_super_sys_array_size(super_copy);
2460
2461 ptr = super_copy->sys_chunk_array;
2462 cur = 0;
2463
2464 while (cur < array_size) {
2465 disk_key = (struct btrfs_disk_key *)ptr;
2466 btrfs_disk_key_to_cpu(&key, disk_key);
2467
2468 len = sizeof(*disk_key);
2469
2470 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2471 chunk = (struct btrfs_chunk *)(ptr + len);
2472 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2473 len += btrfs_chunk_item_size(num_stripes);
2474 } else {
2475 ret = -EIO;
2476 break;
2477 }
2478 if (key.objectid == chunk_objectid &&
2479 key.offset == chunk_offset) {
2480 memmove(ptr, ptr + len, array_size - (cur + len));
2481 array_size -= len;
2482 btrfs_set_super_sys_array_size(super_copy, array_size);
2483 } else {
2484 ptr += len;
2485 cur += len;
2486 }
2487 }
2488 return ret;
2489 }
2490
2491 static int btrfs_relocate_chunk(struct btrfs_root *root,
2492 u64 chunk_tree, u64 chunk_objectid,
2493 u64 chunk_offset)
2494 {
2495 struct extent_map_tree *em_tree;
2496 struct btrfs_root *extent_root;
2497 struct btrfs_trans_handle *trans;
2498 struct extent_map *em;
2499 struct map_lookup *map;
2500 int ret;
2501 int i;
2502
2503 root = root->fs_info->chunk_root;
2504 extent_root = root->fs_info->extent_root;
2505 em_tree = &root->fs_info->mapping_tree.map_tree;
2506
2507 ret = btrfs_can_relocate(extent_root, chunk_offset);
2508 if (ret)
2509 return -ENOSPC;
2510
2511 /* step one, relocate all the extents inside this chunk */
2512 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2513 if (ret)
2514 return ret;
2515
2516 trans = btrfs_start_transaction(root, 0);
2517 if (IS_ERR(trans)) {
2518 ret = PTR_ERR(trans);
2519 btrfs_std_error(root->fs_info, ret);
2520 return ret;
2521 }
2522
2523 lock_chunks(root);
2524
2525 /*
2526 * step two, delete the device extents and the
2527 * chunk tree entries
2528 */
2529 read_lock(&em_tree->lock);
2530 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2531 read_unlock(&em_tree->lock);
2532
2533 BUG_ON(!em || em->start > chunk_offset ||
2534 em->start + em->len < chunk_offset);
2535 map = (struct map_lookup *)em->bdev;
2536
2537 for (i = 0; i < map->num_stripes; i++) {
2538 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev,
2539 map->stripes[i].physical);
2540 BUG_ON(ret);
2541
2542 if (map->stripes[i].dev) {
2543 ret = btrfs_update_device(trans, map->stripes[i].dev);
2544 BUG_ON(ret);
2545 }
2546 }
2547 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
2548 chunk_offset);
2549
2550 BUG_ON(ret);
2551
2552 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2553
2554 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2555 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2556 BUG_ON(ret);
2557 }
2558
2559 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset);
2560 BUG_ON(ret);
2561
2562 write_lock(&em_tree->lock);
2563 remove_extent_mapping(em_tree, em);
2564 write_unlock(&em_tree->lock);
2565
2566 /* once for the tree */
2567 free_extent_map(em);
2568 /* once for us */
2569 free_extent_map(em);
2570
2571 unlock_chunks(root);
2572 btrfs_end_transaction(trans, root);
2573 return 0;
2574 }
2575
2576 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2577 {
2578 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2579 struct btrfs_path *path;
2580 struct extent_buffer *leaf;
2581 struct btrfs_chunk *chunk;
2582 struct btrfs_key key;
2583 struct btrfs_key found_key;
2584 u64 chunk_tree = chunk_root->root_key.objectid;
2585 u64 chunk_type;
2586 bool retried = false;
2587 int failed = 0;
2588 int ret;
2589
2590 path = btrfs_alloc_path();
2591 if (!path)
2592 return -ENOMEM;
2593
2594 again:
2595 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2596 key.offset = (u64)-1;
2597 key.type = BTRFS_CHUNK_ITEM_KEY;
2598
2599 while (1) {
2600 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2601 if (ret < 0)
2602 goto error;
2603 BUG_ON(ret == 0); /* Corruption */
2604
2605 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2606 key.type);
2607 if (ret < 0)
2608 goto error;
2609 if (ret > 0)
2610 break;
2611
2612 leaf = path->nodes[0];
2613 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2614
2615 chunk = btrfs_item_ptr(leaf, path->slots[0],
2616 struct btrfs_chunk);
2617 chunk_type = btrfs_chunk_type(leaf, chunk);
2618 btrfs_release_path(path);
2619
2620 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2621 ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
2622 found_key.objectid,
2623 found_key.offset);
2624 if (ret == -ENOSPC)
2625 failed++;
2626 else if (ret)
2627 BUG();
2628 }
2629
2630 if (found_key.offset == 0)
2631 break;
2632 key.offset = found_key.offset - 1;
2633 }
2634 ret = 0;
2635 if (failed && !retried) {
2636 failed = 0;
2637 retried = true;
2638 goto again;
2639 } else if (WARN_ON(failed && retried)) {
2640 ret = -ENOSPC;
2641 }
2642 error:
2643 btrfs_free_path(path);
2644 return ret;
2645 }
2646
2647 static int insert_balance_item(struct btrfs_root *root,
2648 struct btrfs_balance_control *bctl)
2649 {
2650 struct btrfs_trans_handle *trans;
2651 struct btrfs_balance_item *item;
2652 struct btrfs_disk_balance_args disk_bargs;
2653 struct btrfs_path *path;
2654 struct extent_buffer *leaf;
2655 struct btrfs_key key;
2656 int ret, err;
2657
2658 path = btrfs_alloc_path();
2659 if (!path)
2660 return -ENOMEM;
2661
2662 trans = btrfs_start_transaction(root, 0);
2663 if (IS_ERR(trans)) {
2664 btrfs_free_path(path);
2665 return PTR_ERR(trans);
2666 }
2667
2668 key.objectid = BTRFS_BALANCE_OBJECTID;
2669 key.type = BTRFS_BALANCE_ITEM_KEY;
2670 key.offset = 0;
2671
2672 ret = btrfs_insert_empty_item(trans, root, path, &key,
2673 sizeof(*item));
2674 if (ret)
2675 goto out;
2676
2677 leaf = path->nodes[0];
2678 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2679
2680 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2681
2682 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2683 btrfs_set_balance_data(leaf, item, &disk_bargs);
2684 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2685 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2686 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2687 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2688
2689 btrfs_set_balance_flags(leaf, item, bctl->flags);
2690
2691 btrfs_mark_buffer_dirty(leaf);
2692 out:
2693 btrfs_free_path(path);
2694 err = btrfs_commit_transaction(trans, root);
2695 if (err && !ret)
2696 ret = err;
2697 return ret;
2698 }
2699
2700 static int del_balance_item(struct btrfs_root *root)
2701 {
2702 struct btrfs_trans_handle *trans;
2703 struct btrfs_path *path;
2704 struct btrfs_key key;
2705 int ret, err;
2706
2707 path = btrfs_alloc_path();
2708 if (!path)
2709 return -ENOMEM;
2710
2711 trans = btrfs_start_transaction(root, 0);
2712 if (IS_ERR(trans)) {
2713 btrfs_free_path(path);
2714 return PTR_ERR(trans);
2715 }
2716
2717 key.objectid = BTRFS_BALANCE_OBJECTID;
2718 key.type = BTRFS_BALANCE_ITEM_KEY;
2719 key.offset = 0;
2720
2721 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2722 if (ret < 0)
2723 goto out;
2724 if (ret > 0) {
2725 ret = -ENOENT;
2726 goto out;
2727 }
2728
2729 ret = btrfs_del_item(trans, root, path);
2730 out:
2731 btrfs_free_path(path);
2732 err = btrfs_commit_transaction(trans, root);
2733 if (err && !ret)
2734 ret = err;
2735 return ret;
2736 }
2737
2738 /*
2739 * This is a heuristic used to reduce the number of chunks balanced on
2740 * resume after balance was interrupted.
2741 */
2742 static void update_balance_args(struct btrfs_balance_control *bctl)
2743 {
2744 /*
2745 * Turn on soft mode for chunk types that were being converted.
2746 */
2747 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
2748 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
2749 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
2750 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
2751 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
2752 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
2753
2754 /*
2755 * Turn on usage filter if is not already used. The idea is
2756 * that chunks that we have already balanced should be
2757 * reasonably full. Don't do it for chunks that are being
2758 * converted - that will keep us from relocating unconverted
2759 * (albeit full) chunks.
2760 */
2761 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2762 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2763 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
2764 bctl->data.usage = 90;
2765 }
2766 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2767 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2768 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
2769 bctl->sys.usage = 90;
2770 }
2771 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2772 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2773 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
2774 bctl->meta.usage = 90;
2775 }
2776 }
2777
2778 /*
2779 * Should be called with both balance and volume mutexes held to
2780 * serialize other volume operations (add_dev/rm_dev/resize) with
2781 * restriper. Same goes for unset_balance_control.
2782 */
2783 static void set_balance_control(struct btrfs_balance_control *bctl)
2784 {
2785 struct btrfs_fs_info *fs_info = bctl->fs_info;
2786
2787 BUG_ON(fs_info->balance_ctl);
2788
2789 spin_lock(&fs_info->balance_lock);
2790 fs_info->balance_ctl = bctl;
2791 spin_unlock(&fs_info->balance_lock);
2792 }
2793
2794 static void unset_balance_control(struct btrfs_fs_info *fs_info)
2795 {
2796 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
2797
2798 BUG_ON(!fs_info->balance_ctl);
2799
2800 spin_lock(&fs_info->balance_lock);
2801 fs_info->balance_ctl = NULL;
2802 spin_unlock(&fs_info->balance_lock);
2803
2804 kfree(bctl);
2805 }
2806
2807 /*
2808 * Balance filters. Return 1 if chunk should be filtered out
2809 * (should not be balanced).
2810 */
2811 static int chunk_profiles_filter(u64 chunk_type,
2812 struct btrfs_balance_args *bargs)
2813 {
2814 chunk_type = chunk_to_extended(chunk_type) &
2815 BTRFS_EXTENDED_PROFILE_MASK;
2816
2817 if (bargs->profiles & chunk_type)
2818 return 0;
2819
2820 return 1;
2821 }
2822
2823 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
2824 struct btrfs_balance_args *bargs)
2825 {
2826 struct btrfs_block_group_cache *cache;
2827 u64 chunk_used, user_thresh;
2828 int ret = 1;
2829
2830 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2831 chunk_used = btrfs_block_group_used(&cache->item);
2832
2833 if (bargs->usage == 0)
2834 user_thresh = 1;
2835 else if (bargs->usage > 100)
2836 user_thresh = cache->key.offset;
2837 else
2838 user_thresh = div_factor_fine(cache->key.offset,
2839 bargs->usage);
2840
2841 if (chunk_used < user_thresh)
2842 ret = 0;
2843
2844 btrfs_put_block_group(cache);
2845 return ret;
2846 }
2847
2848 static int chunk_devid_filter(struct extent_buffer *leaf,
2849 struct btrfs_chunk *chunk,
2850 struct btrfs_balance_args *bargs)
2851 {
2852 struct btrfs_stripe *stripe;
2853 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2854 int i;
2855
2856 for (i = 0; i < num_stripes; i++) {
2857 stripe = btrfs_stripe_nr(chunk, i);
2858 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
2859 return 0;
2860 }
2861
2862 return 1;
2863 }
2864
2865 /* [pstart, pend) */
2866 static int chunk_drange_filter(struct extent_buffer *leaf,
2867 struct btrfs_chunk *chunk,
2868 u64 chunk_offset,
2869 struct btrfs_balance_args *bargs)
2870 {
2871 struct btrfs_stripe *stripe;
2872 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2873 u64 stripe_offset;
2874 u64 stripe_length;
2875 int factor;
2876 int i;
2877
2878 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
2879 return 0;
2880
2881 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
2882 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
2883 factor = num_stripes / 2;
2884 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
2885 factor = num_stripes - 1;
2886 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
2887 factor = num_stripes - 2;
2888 } else {
2889 factor = num_stripes;
2890 }
2891
2892 for (i = 0; i < num_stripes; i++) {
2893 stripe = btrfs_stripe_nr(chunk, i);
2894 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
2895 continue;
2896
2897 stripe_offset = btrfs_stripe_offset(leaf, stripe);
2898 stripe_length = btrfs_chunk_length(leaf, chunk);
2899 do_div(stripe_length, factor);
2900
2901 if (stripe_offset < bargs->pend &&
2902 stripe_offset + stripe_length > bargs->pstart)
2903 return 0;
2904 }
2905
2906 return 1;
2907 }
2908
2909 /* [vstart, vend) */
2910 static int chunk_vrange_filter(struct extent_buffer *leaf,
2911 struct btrfs_chunk *chunk,
2912 u64 chunk_offset,
2913 struct btrfs_balance_args *bargs)
2914 {
2915 if (chunk_offset < bargs->vend &&
2916 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
2917 /* at least part of the chunk is inside this vrange */
2918 return 0;
2919
2920 return 1;
2921 }
2922
2923 static int chunk_soft_convert_filter(u64 chunk_type,
2924 struct btrfs_balance_args *bargs)
2925 {
2926 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
2927 return 0;
2928
2929 chunk_type = chunk_to_extended(chunk_type) &
2930 BTRFS_EXTENDED_PROFILE_MASK;
2931
2932 if (bargs->target == chunk_type)
2933 return 1;
2934
2935 return 0;
2936 }
2937
2938 static int should_balance_chunk(struct btrfs_root *root,
2939 struct extent_buffer *leaf,
2940 struct btrfs_chunk *chunk, u64 chunk_offset)
2941 {
2942 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
2943 struct btrfs_balance_args *bargs = NULL;
2944 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
2945
2946 /* type filter */
2947 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
2948 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
2949 return 0;
2950 }
2951
2952 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
2953 bargs = &bctl->data;
2954 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
2955 bargs = &bctl->sys;
2956 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
2957 bargs = &bctl->meta;
2958
2959 /* profiles filter */
2960 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
2961 chunk_profiles_filter(chunk_type, bargs)) {
2962 return 0;
2963 }
2964
2965 /* usage filter */
2966 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
2967 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
2968 return 0;
2969 }
2970
2971 /* devid filter */
2972 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
2973 chunk_devid_filter(leaf, chunk, bargs)) {
2974 return 0;
2975 }
2976
2977 /* drange filter, makes sense only with devid filter */
2978 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
2979 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
2980 return 0;
2981 }
2982
2983 /* vrange filter */
2984 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
2985 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
2986 return 0;
2987 }
2988
2989 /* soft profile changing mode */
2990 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
2991 chunk_soft_convert_filter(chunk_type, bargs)) {
2992 return 0;
2993 }
2994
2995 /*
2996 * limited by count, must be the last filter
2997 */
2998 if ((bargs->flags & BTRFS_BALANCE_ARGS_LIMIT)) {
2999 if (bargs->limit == 0)
3000 return 0;
3001 else
3002 bargs->limit--;
3003 }
3004
3005 return 1;
3006 }
3007
3008 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
3009 {
3010 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3011 struct btrfs_root *chunk_root = fs_info->chunk_root;
3012 struct btrfs_root *dev_root = fs_info->dev_root;
3013 struct list_head *devices;
3014 struct btrfs_device *device;
3015 u64 old_size;
3016 u64 size_to_free;
3017 struct btrfs_chunk *chunk;
3018 struct btrfs_path *path;
3019 struct btrfs_key key;
3020 struct btrfs_key found_key;
3021 struct btrfs_trans_handle *trans;
3022 struct extent_buffer *leaf;
3023 int slot;
3024 int ret;
3025 int enospc_errors = 0;
3026 bool counting = true;
3027 u64 limit_data = bctl->data.limit;
3028 u64 limit_meta = bctl->meta.limit;
3029 u64 limit_sys = bctl->sys.limit;
3030
3031 /* step one make some room on all the devices */
3032 devices = &fs_info->fs_devices->devices;
3033 list_for_each_entry(device, devices, dev_list) {
3034 old_size = device->total_bytes;
3035 size_to_free = div_factor(old_size, 1);
3036 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
3037 if (!device->writeable ||
3038 device->total_bytes - device->bytes_used > size_to_free ||
3039 device->is_tgtdev_for_dev_replace)
3040 continue;
3041
3042 ret = btrfs_shrink_device(device, old_size - size_to_free);
3043 if (ret == -ENOSPC)
3044 break;
3045 BUG_ON(ret);
3046
3047 trans = btrfs_start_transaction(dev_root, 0);
3048 BUG_ON(IS_ERR(trans));
3049
3050 ret = btrfs_grow_device(trans, device, old_size);
3051 BUG_ON(ret);
3052
3053 btrfs_end_transaction(trans, dev_root);
3054 }
3055
3056 /* step two, relocate all the chunks */
3057 path = btrfs_alloc_path();
3058 if (!path) {
3059 ret = -ENOMEM;
3060 goto error;
3061 }
3062
3063 /* zero out stat counters */
3064 spin_lock(&fs_info->balance_lock);
3065 memset(&bctl->stat, 0, sizeof(bctl->stat));
3066 spin_unlock(&fs_info->balance_lock);
3067 again:
3068 if (!counting) {
3069 bctl->data.limit = limit_data;
3070 bctl->meta.limit = limit_meta;
3071 bctl->sys.limit = limit_sys;
3072 }
3073 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3074 key.offset = (u64)-1;
3075 key.type = BTRFS_CHUNK_ITEM_KEY;
3076
3077 while (1) {
3078 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
3079 atomic_read(&fs_info->balance_cancel_req)) {
3080 ret = -ECANCELED;
3081 goto error;
3082 }
3083
3084 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
3085 if (ret < 0)
3086 goto error;
3087
3088 /*
3089 * this shouldn't happen, it means the last relocate
3090 * failed
3091 */
3092 if (ret == 0)
3093 BUG(); /* FIXME break ? */
3094
3095 ret = btrfs_previous_item(chunk_root, path, 0,
3096 BTRFS_CHUNK_ITEM_KEY);
3097 if (ret) {
3098 ret = 0;
3099 break;
3100 }
3101
3102 leaf = path->nodes[0];
3103 slot = path->slots[0];
3104 btrfs_item_key_to_cpu(leaf, &found_key, slot);
3105
3106 if (found_key.objectid != key.objectid)
3107 break;
3108
3109 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
3110
3111 if (!counting) {
3112 spin_lock(&fs_info->balance_lock);
3113 bctl->stat.considered++;
3114 spin_unlock(&fs_info->balance_lock);
3115 }
3116
3117 ret = should_balance_chunk(chunk_root, leaf, chunk,
3118 found_key.offset);
3119 btrfs_release_path(path);
3120 if (!ret)
3121 goto loop;
3122
3123 if (counting) {
3124 spin_lock(&fs_info->balance_lock);
3125 bctl->stat.expected++;
3126 spin_unlock(&fs_info->balance_lock);
3127 goto loop;
3128 }
3129
3130 ret = btrfs_relocate_chunk(chunk_root,
3131 chunk_root->root_key.objectid,
3132 found_key.objectid,
3133 found_key.offset);
3134 if (ret && ret != -ENOSPC)
3135 goto error;
3136 if (ret == -ENOSPC) {
3137 enospc_errors++;
3138 } else {
3139 spin_lock(&fs_info->balance_lock);
3140 bctl->stat.completed++;
3141 spin_unlock(&fs_info->balance_lock);
3142 }
3143 loop:
3144 if (found_key.offset == 0)
3145 break;
3146 key.offset = found_key.offset - 1;
3147 }
3148
3149 if (counting) {
3150 btrfs_release_path(path);
3151 counting = false;
3152 goto again;
3153 }
3154 error:
3155 btrfs_free_path(path);
3156 if (enospc_errors) {
3157 btrfs_info(fs_info, "%d enospc errors during balance",
3158 enospc_errors);
3159 if (!ret)
3160 ret = -ENOSPC;
3161 }
3162
3163 return ret;
3164 }
3165
3166 /**
3167 * alloc_profile_is_valid - see if a given profile is valid and reduced
3168 * @flags: profile to validate
3169 * @extended: if true @flags is treated as an extended profile
3170 */
3171 static int alloc_profile_is_valid(u64 flags, int extended)
3172 {
3173 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
3174 BTRFS_BLOCK_GROUP_PROFILE_MASK);
3175
3176 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
3177
3178 /* 1) check that all other bits are zeroed */
3179 if (flags & ~mask)
3180 return 0;
3181
3182 /* 2) see if profile is reduced */
3183 if (flags == 0)
3184 return !extended; /* "0" is valid for usual profiles */
3185
3186 /* true if exactly one bit set */
3187 return (flags & (flags - 1)) == 0;
3188 }
3189
3190 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
3191 {
3192 /* cancel requested || normal exit path */
3193 return atomic_read(&fs_info->balance_cancel_req) ||
3194 (atomic_read(&fs_info->balance_pause_req) == 0 &&
3195 atomic_read(&fs_info->balance_cancel_req) == 0);
3196 }
3197
3198 static void __cancel_balance(struct btrfs_fs_info *fs_info)
3199 {
3200 int ret;
3201
3202 unset_balance_control(fs_info);
3203 ret = del_balance_item(fs_info->tree_root);
3204 if (ret)
3205 btrfs_std_error(fs_info, ret);
3206
3207 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3208 }
3209
3210 /*
3211 * Should be called with both balance and volume mutexes held
3212 */
3213 int btrfs_balance(struct btrfs_balance_control *bctl,
3214 struct btrfs_ioctl_balance_args *bargs)
3215 {
3216 struct btrfs_fs_info *fs_info = bctl->fs_info;
3217 u64 allowed;
3218 int mixed = 0;
3219 int ret;
3220 u64 num_devices;
3221 unsigned seq;
3222
3223 if (btrfs_fs_closing(fs_info) ||
3224 atomic_read(&fs_info->balance_pause_req) ||
3225 atomic_read(&fs_info->balance_cancel_req)) {
3226 ret = -EINVAL;
3227 goto out;
3228 }
3229
3230 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3231 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3232 mixed = 1;
3233
3234 /*
3235 * In case of mixed groups both data and meta should be picked,
3236 * and identical options should be given for both of them.
3237 */
3238 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3239 if (mixed && (bctl->flags & allowed)) {
3240 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3241 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3242 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3243 btrfs_err(fs_info, "with mixed groups data and "
3244 "metadata balance options must be the same");
3245 ret = -EINVAL;
3246 goto out;
3247 }
3248 }
3249
3250 num_devices = fs_info->fs_devices->num_devices;
3251 btrfs_dev_replace_lock(&fs_info->dev_replace);
3252 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3253 BUG_ON(num_devices < 1);
3254 num_devices--;
3255 }
3256 btrfs_dev_replace_unlock(&fs_info->dev_replace);
3257 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3258 if (num_devices == 1)
3259 allowed |= BTRFS_BLOCK_GROUP_DUP;
3260 else if (num_devices > 1)
3261 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3262 if (num_devices > 2)
3263 allowed |= BTRFS_BLOCK_GROUP_RAID5;
3264 if (num_devices > 3)
3265 allowed |= (BTRFS_BLOCK_GROUP_RAID10 |
3266 BTRFS_BLOCK_GROUP_RAID6);
3267 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3268 (!alloc_profile_is_valid(bctl->data.target, 1) ||
3269 (bctl->data.target & ~allowed))) {
3270 btrfs_err(fs_info, "unable to start balance with target "
3271 "data profile %llu",
3272 bctl->data.target);
3273 ret = -EINVAL;
3274 goto out;
3275 }
3276 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3277 (!alloc_profile_is_valid(bctl->meta.target, 1) ||
3278 (bctl->meta.target & ~allowed))) {
3279 btrfs_err(fs_info,
3280 "unable to start balance with target metadata profile %llu",
3281 bctl->meta.target);
3282 ret = -EINVAL;
3283 goto out;
3284 }
3285 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3286 (!alloc_profile_is_valid(bctl->sys.target, 1) ||
3287 (bctl->sys.target & ~allowed))) {
3288 btrfs_err(fs_info,
3289 "unable to start balance with target system profile %llu",
3290 bctl->sys.target);
3291 ret = -EINVAL;
3292 goto out;
3293 }
3294
3295 /* allow dup'ed data chunks only in mixed mode */
3296 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3297 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
3298 btrfs_err(fs_info, "dup for data is not allowed");
3299 ret = -EINVAL;
3300 goto out;
3301 }
3302
3303 /* allow to reduce meta or sys integrity only if force set */
3304 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3305 BTRFS_BLOCK_GROUP_RAID10 |
3306 BTRFS_BLOCK_GROUP_RAID5 |
3307 BTRFS_BLOCK_GROUP_RAID6;
3308 do {
3309 seq = read_seqbegin(&fs_info->profiles_lock);
3310
3311 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3312 (fs_info->avail_system_alloc_bits & allowed) &&
3313 !(bctl->sys.target & allowed)) ||
3314 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3315 (fs_info->avail_metadata_alloc_bits & allowed) &&
3316 !(bctl->meta.target & allowed))) {
3317 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3318 btrfs_info(fs_info, "force reducing metadata integrity");
3319 } else {
3320 btrfs_err(fs_info, "balance will reduce metadata "
3321 "integrity, use force if you want this");
3322 ret = -EINVAL;
3323 goto out;
3324 }
3325 }
3326 } while (read_seqretry(&fs_info->profiles_lock, seq));
3327
3328 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3329 int num_tolerated_disk_barrier_failures;
3330 u64 target = bctl->sys.target;
3331
3332 num_tolerated_disk_barrier_failures =
3333 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3334 if (num_tolerated_disk_barrier_failures > 0 &&
3335 (target &
3336 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 |
3337 BTRFS_AVAIL_ALLOC_BIT_SINGLE)))
3338 num_tolerated_disk_barrier_failures = 0;
3339 else if (num_tolerated_disk_barrier_failures > 1 &&
3340 (target &
3341 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)))
3342 num_tolerated_disk_barrier_failures = 1;
3343
3344 fs_info->num_tolerated_disk_barrier_failures =
3345 num_tolerated_disk_barrier_failures;
3346 }
3347
3348 ret = insert_balance_item(fs_info->tree_root, bctl);
3349 if (ret && ret != -EEXIST)
3350 goto out;
3351
3352 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3353 BUG_ON(ret == -EEXIST);
3354 set_balance_control(bctl);
3355 } else {
3356 BUG_ON(ret != -EEXIST);
3357 spin_lock(&fs_info->balance_lock);
3358 update_balance_args(bctl);
3359 spin_unlock(&fs_info->balance_lock);
3360 }
3361
3362 atomic_inc(&fs_info->balance_running);
3363 mutex_unlock(&fs_info->balance_mutex);
3364
3365 ret = __btrfs_balance(fs_info);
3366
3367 mutex_lock(&fs_info->balance_mutex);
3368 atomic_dec(&fs_info->balance_running);
3369
3370 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3371 fs_info->num_tolerated_disk_barrier_failures =
3372 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3373 }
3374
3375 if (bargs) {
3376 memset(bargs, 0, sizeof(*bargs));
3377 update_ioctl_balance_args(fs_info, 0, bargs);
3378 }
3379
3380 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3381 balance_need_close(fs_info)) {
3382 __cancel_balance(fs_info);
3383 }
3384
3385 wake_up(&fs_info->balance_wait_q);
3386
3387 return ret;
3388 out:
3389 if (bctl->flags & BTRFS_BALANCE_RESUME)
3390 __cancel_balance(fs_info);
3391 else {
3392 kfree(bctl);
3393 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3394 }
3395 return ret;
3396 }
3397
3398 static int balance_kthread(void *data)
3399 {
3400 struct btrfs_fs_info *fs_info = data;
3401 int ret = 0;
3402
3403 mutex_lock(&fs_info->volume_mutex);
3404 mutex_lock(&fs_info->balance_mutex);
3405
3406 if (fs_info->balance_ctl) {
3407 btrfs_info(fs_info, "continuing balance");
3408 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3409 }
3410
3411 mutex_unlock(&fs_info->balance_mutex);
3412 mutex_unlock(&fs_info->volume_mutex);
3413
3414 return ret;
3415 }
3416
3417 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3418 {
3419 struct task_struct *tsk;
3420
3421 spin_lock(&fs_info->balance_lock);
3422 if (!fs_info->balance_ctl) {
3423 spin_unlock(&fs_info->balance_lock);
3424 return 0;
3425 }
3426 spin_unlock(&fs_info->balance_lock);
3427
3428 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3429 btrfs_info(fs_info, "force skipping balance");
3430 return 0;
3431 }
3432
3433 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3434 return PTR_ERR_OR_ZERO(tsk);
3435 }
3436
3437 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3438 {
3439 struct btrfs_balance_control *bctl;
3440 struct btrfs_balance_item *item;
3441 struct btrfs_disk_balance_args disk_bargs;
3442 struct btrfs_path *path;
3443 struct extent_buffer *leaf;
3444 struct btrfs_key key;
3445 int ret;
3446
3447 path = btrfs_alloc_path();
3448 if (!path)
3449 return -ENOMEM;
3450
3451 key.objectid = BTRFS_BALANCE_OBJECTID;
3452 key.type = BTRFS_BALANCE_ITEM_KEY;
3453 key.offset = 0;
3454
3455 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3456 if (ret < 0)
3457 goto out;
3458 if (ret > 0) { /* ret = -ENOENT; */
3459 ret = 0;
3460 goto out;
3461 }
3462
3463 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3464 if (!bctl) {
3465 ret = -ENOMEM;
3466 goto out;
3467 }
3468
3469 leaf = path->nodes[0];
3470 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3471
3472 bctl->fs_info = fs_info;
3473 bctl->flags = btrfs_balance_flags(leaf, item);
3474 bctl->flags |= BTRFS_BALANCE_RESUME;
3475
3476 btrfs_balance_data(leaf, item, &disk_bargs);
3477 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3478 btrfs_balance_meta(leaf, item, &disk_bargs);
3479 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3480 btrfs_balance_sys(leaf, item, &disk_bargs);
3481 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3482
3483 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3484
3485 mutex_lock(&fs_info->volume_mutex);
3486 mutex_lock(&fs_info->balance_mutex);
3487
3488 set_balance_control(bctl);
3489
3490 mutex_unlock(&fs_info->balance_mutex);
3491 mutex_unlock(&fs_info->volume_mutex);
3492 out:
3493 btrfs_free_path(path);
3494 return ret;
3495 }
3496
3497 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3498 {
3499 int ret = 0;
3500
3501 mutex_lock(&fs_info->balance_mutex);
3502 if (!fs_info->balance_ctl) {
3503 mutex_unlock(&fs_info->balance_mutex);
3504 return -ENOTCONN;
3505 }
3506
3507 if (atomic_read(&fs_info->balance_running)) {
3508 atomic_inc(&fs_info->balance_pause_req);
3509 mutex_unlock(&fs_info->balance_mutex);
3510
3511 wait_event(fs_info->balance_wait_q,
3512 atomic_read(&fs_info->balance_running) == 0);
3513
3514 mutex_lock(&fs_info->balance_mutex);
3515 /* we are good with balance_ctl ripped off from under us */
3516 BUG_ON(atomic_read(&fs_info->balance_running));
3517 atomic_dec(&fs_info->balance_pause_req);
3518 } else {
3519 ret = -ENOTCONN;
3520 }
3521
3522 mutex_unlock(&fs_info->balance_mutex);
3523 return ret;
3524 }
3525
3526 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3527 {
3528 if (fs_info->sb->s_flags & MS_RDONLY)
3529 return -EROFS;
3530
3531 mutex_lock(&fs_info->balance_mutex);
3532 if (!fs_info->balance_ctl) {
3533 mutex_unlock(&fs_info->balance_mutex);
3534 return -ENOTCONN;
3535 }
3536
3537 atomic_inc(&fs_info->balance_cancel_req);
3538 /*
3539 * if we are running just wait and return, balance item is
3540 * deleted in btrfs_balance in this case
3541 */
3542 if (atomic_read(&fs_info->balance_running)) {
3543 mutex_unlock(&fs_info->balance_mutex);
3544 wait_event(fs_info->balance_wait_q,
3545 atomic_read(&fs_info->balance_running) == 0);
3546 mutex_lock(&fs_info->balance_mutex);
3547 } else {
3548 /* __cancel_balance needs volume_mutex */
3549 mutex_unlock(&fs_info->balance_mutex);
3550 mutex_lock(&fs_info->volume_mutex);
3551 mutex_lock(&fs_info->balance_mutex);
3552
3553 if (fs_info->balance_ctl)
3554 __cancel_balance(fs_info);
3555
3556 mutex_unlock(&fs_info->volume_mutex);
3557 }
3558
3559 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
3560 atomic_dec(&fs_info->balance_cancel_req);
3561 mutex_unlock(&fs_info->balance_mutex);
3562 return 0;
3563 }
3564
3565 static int btrfs_uuid_scan_kthread(void *data)
3566 {
3567 struct btrfs_fs_info *fs_info = data;
3568 struct btrfs_root *root = fs_info->tree_root;
3569 struct btrfs_key key;
3570 struct btrfs_key max_key;
3571 struct btrfs_path *path = NULL;
3572 int ret = 0;
3573 struct extent_buffer *eb;
3574 int slot;
3575 struct btrfs_root_item root_item;
3576 u32 item_size;
3577 struct btrfs_trans_handle *trans = NULL;
3578
3579 path = btrfs_alloc_path();
3580 if (!path) {
3581 ret = -ENOMEM;
3582 goto out;
3583 }
3584
3585 key.objectid = 0;
3586 key.type = BTRFS_ROOT_ITEM_KEY;
3587 key.offset = 0;
3588
3589 max_key.objectid = (u64)-1;
3590 max_key.type = BTRFS_ROOT_ITEM_KEY;
3591 max_key.offset = (u64)-1;
3592
3593 path->keep_locks = 1;
3594
3595 while (1) {
3596 ret = btrfs_search_forward(root, &key, path, 0);
3597 if (ret) {
3598 if (ret > 0)
3599 ret = 0;
3600 break;
3601 }
3602
3603 if (key.type != BTRFS_ROOT_ITEM_KEY ||
3604 (key.objectid < BTRFS_FIRST_FREE_OBJECTID &&
3605 key.objectid != BTRFS_FS_TREE_OBJECTID) ||
3606 key.objectid > BTRFS_LAST_FREE_OBJECTID)
3607 goto skip;
3608
3609 eb = path->nodes[0];
3610 slot = path->slots[0];
3611 item_size = btrfs_item_size_nr(eb, slot);
3612 if (item_size < sizeof(root_item))
3613 goto skip;
3614
3615 read_extent_buffer(eb, &root_item,
3616 btrfs_item_ptr_offset(eb, slot),
3617 (int)sizeof(root_item));
3618 if (btrfs_root_refs(&root_item) == 0)
3619 goto skip;
3620
3621 if (!btrfs_is_empty_uuid(root_item.uuid) ||
3622 !btrfs_is_empty_uuid(root_item.received_uuid)) {
3623 if (trans)
3624 goto update_tree;
3625
3626 btrfs_release_path(path);
3627 /*
3628 * 1 - subvol uuid item
3629 * 1 - received_subvol uuid item
3630 */
3631 trans = btrfs_start_transaction(fs_info->uuid_root, 2);
3632 if (IS_ERR(trans)) {
3633 ret = PTR_ERR(trans);
3634 break;
3635 }
3636 continue;
3637 } else {
3638 goto skip;
3639 }
3640 update_tree:
3641 if (!btrfs_is_empty_uuid(root_item.uuid)) {
3642 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3643 root_item.uuid,
3644 BTRFS_UUID_KEY_SUBVOL,
3645 key.objectid);
3646 if (ret < 0) {
3647 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3648 ret);
3649 break;
3650 }
3651 }
3652
3653 if (!btrfs_is_empty_uuid(root_item.received_uuid)) {
3654 ret = btrfs_uuid_tree_add(trans, fs_info->uuid_root,
3655 root_item.received_uuid,
3656 BTRFS_UUID_KEY_RECEIVED_SUBVOL,
3657 key.objectid);
3658 if (ret < 0) {
3659 btrfs_warn(fs_info, "uuid_tree_add failed %d",
3660 ret);
3661 break;
3662 }
3663 }
3664
3665 skip:
3666 if (trans) {
3667 ret = btrfs_end_transaction(trans, fs_info->uuid_root);
3668 trans = NULL;
3669 if (ret)
3670 break;
3671 }
3672
3673 btrfs_release_path(path);
3674 if (key.offset < (u64)-1) {
3675 key.offset++;
3676 } else if (key.type < BTRFS_ROOT_ITEM_KEY) {
3677 key.offset = 0;
3678 key.type = BTRFS_ROOT_ITEM_KEY;
3679 } else if (key.objectid < (u64)-1) {
3680 key.offset = 0;
3681 key.type = BTRFS_ROOT_ITEM_KEY;
3682 key.objectid++;
3683 } else {
3684 break;
3685 }
3686 cond_resched();
3687 }
3688
3689 out:
3690 btrfs_free_path(path);
3691 if (trans && !IS_ERR(trans))
3692 btrfs_end_transaction(trans, fs_info->uuid_root);
3693 if (ret)
3694 btrfs_warn(fs_info, "btrfs_uuid_scan_kthread failed %d", ret);
3695 else
3696 fs_info->update_uuid_tree_gen = 1;
3697 up(&fs_info->uuid_tree_rescan_sem);
3698 return 0;
3699 }
3700
3701 /*
3702 * Callback for btrfs_uuid_tree_iterate().
3703 * returns:
3704 * 0 check succeeded, the entry is not outdated.
3705 * < 0 if an error occured.
3706 * > 0 if the check failed, which means the caller shall remove the entry.
3707 */
3708 static int btrfs_check_uuid_tree_entry(struct btrfs_fs_info *fs_info,
3709 u8 *uuid, u8 type, u64 subid)
3710 {
3711 struct btrfs_key key;
3712 int ret = 0;
3713 struct btrfs_root *subvol_root;
3714
3715 if (type != BTRFS_UUID_KEY_SUBVOL &&
3716 type != BTRFS_UUID_KEY_RECEIVED_SUBVOL)
3717 goto out;
3718
3719 key.objectid = subid;
3720 key.type = BTRFS_ROOT_ITEM_KEY;
3721 key.offset = (u64)-1;
3722 subvol_root = btrfs_read_fs_root_no_name(fs_info, &key);
3723 if (IS_ERR(subvol_root)) {
3724 ret = PTR_ERR(subvol_root);
3725 if (ret == -ENOENT)
3726 ret = 1;
3727 goto out;
3728 }
3729
3730 switch (type) {
3731 case BTRFS_UUID_KEY_SUBVOL:
3732 if (memcmp(uuid, subvol_root->root_item.uuid, BTRFS_UUID_SIZE))
3733 ret = 1;
3734 break;
3735 case BTRFS_UUID_KEY_RECEIVED_SUBVOL:
3736 if (memcmp(uuid, subvol_root->root_item.received_uuid,
3737 BTRFS_UUID_SIZE))
3738 ret = 1;
3739 break;
3740 }
3741
3742 out:
3743 return ret;
3744 }
3745
3746 static int btrfs_uuid_rescan_kthread(void *data)
3747 {
3748 struct btrfs_fs_info *fs_info = (struct btrfs_fs_info *)data;
3749 int ret;
3750
3751 /*
3752 * 1st step is to iterate through the existing UUID tree and
3753 * to delete all entries that contain outdated data.
3754 * 2nd step is to add all missing entries to the UUID tree.
3755 */
3756 ret = btrfs_uuid_tree_iterate(fs_info, btrfs_check_uuid_tree_entry);
3757 if (ret < 0) {
3758 btrfs_warn(fs_info, "iterating uuid_tree failed %d", ret);
3759 up(&fs_info->uuid_tree_rescan_sem);
3760 return ret;
3761 }
3762 return btrfs_uuid_scan_kthread(data);
3763 }
3764
3765 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info)
3766 {
3767 struct btrfs_trans_handle *trans;
3768 struct btrfs_root *tree_root = fs_info->tree_root;
3769 struct btrfs_root *uuid_root;
3770 struct task_struct *task;
3771 int ret;
3772
3773 /*
3774 * 1 - root node
3775 * 1 - root item
3776 */
3777 trans = btrfs_start_transaction(tree_root, 2);
3778 if (IS_ERR(trans))
3779 return PTR_ERR(trans);
3780
3781 uuid_root = btrfs_create_tree(trans, fs_info,
3782 BTRFS_UUID_TREE_OBJECTID);
3783 if (IS_ERR(uuid_root)) {
3784 btrfs_abort_transaction(trans, tree_root,
3785 PTR_ERR(uuid_root));
3786 return PTR_ERR(uuid_root);
3787 }
3788
3789 fs_info->uuid_root = uuid_root;
3790
3791 ret = btrfs_commit_transaction(trans, tree_root);
3792 if (ret)
3793 return ret;
3794
3795 down(&fs_info->uuid_tree_rescan_sem);
3796 task = kthread_run(btrfs_uuid_scan_kthread, fs_info, "btrfs-uuid");
3797 if (IS_ERR(task)) {
3798 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3799 btrfs_warn(fs_info, "failed to start uuid_scan task");
3800 up(&fs_info->uuid_tree_rescan_sem);
3801 return PTR_ERR(task);
3802 }
3803
3804 return 0;
3805 }
3806
3807 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info)
3808 {
3809 struct task_struct *task;
3810
3811 down(&fs_info->uuid_tree_rescan_sem);
3812 task = kthread_run(btrfs_uuid_rescan_kthread, fs_info, "btrfs-uuid");
3813 if (IS_ERR(task)) {
3814 /* fs_info->update_uuid_tree_gen remains 0 in all error case */
3815 btrfs_warn(fs_info, "failed to start uuid_rescan task");
3816 up(&fs_info->uuid_tree_rescan_sem);
3817 return PTR_ERR(task);
3818 }
3819
3820 return 0;
3821 }
3822
3823 /*
3824 * shrinking a device means finding all of the device extents past
3825 * the new size, and then following the back refs to the chunks.
3826 * The chunk relocation code actually frees the device extent
3827 */
3828 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
3829 {
3830 struct btrfs_trans_handle *trans;
3831 struct btrfs_root *root = device->dev_root;
3832 struct btrfs_dev_extent *dev_extent = NULL;
3833 struct btrfs_path *path;
3834 u64 length;
3835 u64 chunk_tree;
3836 u64 chunk_objectid;
3837 u64 chunk_offset;
3838 int ret;
3839 int slot;
3840 int failed = 0;
3841 bool retried = false;
3842 struct extent_buffer *l;
3843 struct btrfs_key key;
3844 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3845 u64 old_total = btrfs_super_total_bytes(super_copy);
3846 u64 old_size = device->total_bytes;
3847 u64 diff = device->total_bytes - new_size;
3848
3849 if (device->is_tgtdev_for_dev_replace)
3850 return -EINVAL;
3851
3852 path = btrfs_alloc_path();
3853 if (!path)
3854 return -ENOMEM;
3855
3856 path->reada = 2;
3857
3858 lock_chunks(root);
3859
3860 device->total_bytes = new_size;
3861 if (device->writeable) {
3862 device->fs_devices->total_rw_bytes -= diff;
3863 spin_lock(&root->fs_info->free_chunk_lock);
3864 root->fs_info->free_chunk_space -= diff;
3865 spin_unlock(&root->fs_info->free_chunk_lock);
3866 }
3867 unlock_chunks(root);
3868
3869 again:
3870 key.objectid = device->devid;
3871 key.offset = (u64)-1;
3872 key.type = BTRFS_DEV_EXTENT_KEY;
3873
3874 do {
3875 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3876 if (ret < 0)
3877 goto done;
3878
3879 ret = btrfs_previous_item(root, path, 0, key.type);
3880 if (ret < 0)
3881 goto done;
3882 if (ret) {
3883 ret = 0;
3884 btrfs_release_path(path);
3885 break;
3886 }
3887
3888 l = path->nodes[0];
3889 slot = path->slots[0];
3890 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
3891
3892 if (key.objectid != device->devid) {
3893 btrfs_release_path(path);
3894 break;
3895 }
3896
3897 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
3898 length = btrfs_dev_extent_length(l, dev_extent);
3899
3900 if (key.offset + length <= new_size) {
3901 btrfs_release_path(path);
3902 break;
3903 }
3904
3905 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
3906 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
3907 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
3908 btrfs_release_path(path);
3909
3910 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
3911 chunk_offset);
3912 if (ret && ret != -ENOSPC)
3913 goto done;
3914 if (ret == -ENOSPC)
3915 failed++;
3916 } while (key.offset-- > 0);
3917
3918 if (failed && !retried) {
3919 failed = 0;
3920 retried = true;
3921 goto again;
3922 } else if (failed && retried) {
3923 ret = -ENOSPC;
3924 lock_chunks(root);
3925
3926 device->total_bytes = old_size;
3927 if (device->writeable)
3928 device->fs_devices->total_rw_bytes += diff;
3929 spin_lock(&root->fs_info->free_chunk_lock);
3930 root->fs_info->free_chunk_space += diff;
3931 spin_unlock(&root->fs_info->free_chunk_lock);
3932 unlock_chunks(root);
3933 goto done;
3934 }
3935
3936 /* Shrinking succeeded, else we would be at "done". */
3937 trans = btrfs_start_transaction(root, 0);
3938 if (IS_ERR(trans)) {
3939 ret = PTR_ERR(trans);
3940 goto done;
3941 }
3942
3943 lock_chunks(root);
3944
3945 device->disk_total_bytes = new_size;
3946 /* Now btrfs_update_device() will change the on-disk size. */
3947 ret = btrfs_update_device(trans, device);
3948 if (ret) {
3949 unlock_chunks(root);
3950 btrfs_end_transaction(trans, root);
3951 goto done;
3952 }
3953 WARN_ON(diff > old_total);
3954 btrfs_set_super_total_bytes(super_copy, old_total - diff);
3955 unlock_chunks(root);
3956 btrfs_end_transaction(trans, root);
3957 done:
3958 btrfs_free_path(path);
3959 return ret;
3960 }
3961
3962 static int btrfs_add_system_chunk(struct btrfs_root *root,
3963 struct btrfs_key *key,
3964 struct btrfs_chunk *chunk, int item_size)
3965 {
3966 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3967 struct btrfs_disk_key disk_key;
3968 u32 array_size;
3969 u8 *ptr;
3970
3971 array_size = btrfs_super_sys_array_size(super_copy);
3972 if (array_size + item_size + sizeof(disk_key)
3973 > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
3974 return -EFBIG;
3975
3976 ptr = super_copy->sys_chunk_array + array_size;
3977 btrfs_cpu_key_to_disk(&disk_key, key);
3978 memcpy(ptr, &disk_key, sizeof(disk_key));
3979 ptr += sizeof(disk_key);
3980 memcpy(ptr, chunk, item_size);
3981 item_size += sizeof(disk_key);
3982 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
3983 return 0;
3984 }
3985
3986 /*
3987 * sort the devices in descending order by max_avail, total_avail
3988 */
3989 static int btrfs_cmp_device_info(const void *a, const void *b)
3990 {
3991 const struct btrfs_device_info *di_a = a;
3992 const struct btrfs_device_info *di_b = b;
3993
3994 if (di_a->max_avail > di_b->max_avail)
3995 return -1;
3996 if (di_a->max_avail < di_b->max_avail)
3997 return 1;
3998 if (di_a->total_avail > di_b->total_avail)
3999 return -1;
4000 if (di_a->total_avail < di_b->total_avail)
4001 return 1;
4002 return 0;
4003 }
4004
4005 static struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
4006 [BTRFS_RAID_RAID10] = {
4007 .sub_stripes = 2,
4008 .dev_stripes = 1,
4009 .devs_max = 0, /* 0 == as many as possible */
4010 .devs_min = 4,
4011 .devs_increment = 2,
4012 .ncopies = 2,
4013 },
4014 [BTRFS_RAID_RAID1] = {
4015 .sub_stripes = 1,
4016 .dev_stripes = 1,
4017 .devs_max = 2,
4018 .devs_min = 2,
4019 .devs_increment = 2,
4020 .ncopies = 2,
4021 },
4022 [BTRFS_RAID_DUP] = {
4023 .sub_stripes = 1,
4024 .dev_stripes = 2,
4025 .devs_max = 1,
4026 .devs_min = 1,
4027 .devs_increment = 1,
4028 .ncopies = 2,
4029 },
4030 [BTRFS_RAID_RAID0] = {
4031 .sub_stripes = 1,
4032 .dev_stripes = 1,
4033 .devs_max = 0,
4034 .devs_min = 2,
4035 .devs_increment = 1,
4036 .ncopies = 1,
4037 },
4038 [BTRFS_RAID_SINGLE] = {
4039 .sub_stripes = 1,
4040 .dev_stripes = 1,
4041 .devs_max = 1,
4042 .devs_min = 1,
4043 .devs_increment = 1,
4044 .ncopies = 1,
4045 },
4046 [BTRFS_RAID_RAID5] = {
4047 .sub_stripes = 1,
4048 .dev_stripes = 1,
4049 .devs_max = 0,
4050 .devs_min = 2,
4051 .devs_increment = 1,
4052 .ncopies = 2,
4053 },
4054 [BTRFS_RAID_RAID6] = {
4055 .sub_stripes = 1,
4056 .dev_stripes = 1,
4057 .devs_max = 0,
4058 .devs_min = 3,
4059 .devs_increment = 1,
4060 .ncopies = 3,
4061 },
4062 };
4063
4064 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
4065 {
4066 /* TODO allow them to set a preferred stripe size */
4067 return 64 * 1024;
4068 }
4069
4070 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
4071 {
4072 if (!(type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)))
4073 return;
4074
4075 btrfs_set_fs_incompat(info, RAID56);
4076 }
4077
4078 #define BTRFS_MAX_DEVS(r) ((BTRFS_LEAF_DATA_SIZE(r) \
4079 - sizeof(struct btrfs_item) \
4080 - sizeof(struct btrfs_chunk)) \
4081 / sizeof(struct btrfs_stripe) + 1)
4082
4083 #define BTRFS_MAX_DEVS_SYS_CHUNK ((BTRFS_SYSTEM_CHUNK_ARRAY_SIZE \
4084 - 2 * sizeof(struct btrfs_disk_key) \
4085 - 2 * sizeof(struct btrfs_chunk)) \
4086 / sizeof(struct btrfs_stripe) + 1)
4087
4088 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4089 struct btrfs_root *extent_root, u64 start,
4090 u64 type)
4091 {
4092 struct btrfs_fs_info *info = extent_root->fs_info;
4093 struct btrfs_fs_devices *fs_devices = info->fs_devices;
4094 struct list_head *cur;
4095 struct map_lookup *map = NULL;
4096 struct extent_map_tree *em_tree;
4097 struct extent_map *em;
4098 struct btrfs_device_info *devices_info = NULL;
4099 u64 total_avail;
4100 int num_stripes; /* total number of stripes to allocate */
4101 int data_stripes; /* number of stripes that count for
4102 block group size */
4103 int sub_stripes; /* sub_stripes info for map */
4104 int dev_stripes; /* stripes per dev */
4105 int devs_max; /* max devs to use */
4106 int devs_min; /* min devs needed */
4107 int devs_increment; /* ndevs has to be a multiple of this */
4108 int ncopies; /* how many copies to data has */
4109 int ret;
4110 u64 max_stripe_size;
4111 u64 max_chunk_size;
4112 u64 stripe_size;
4113 u64 num_bytes;
4114 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
4115 int ndevs;
4116 int i;
4117 int j;
4118 int index;
4119
4120 BUG_ON(!alloc_profile_is_valid(type, 0));
4121
4122 if (list_empty(&fs_devices->alloc_list))
4123 return -ENOSPC;
4124
4125 index = __get_raid_index(type);
4126
4127 sub_stripes = btrfs_raid_array[index].sub_stripes;
4128 dev_stripes = btrfs_raid_array[index].dev_stripes;
4129 devs_max = btrfs_raid_array[index].devs_max;
4130 devs_min = btrfs_raid_array[index].devs_min;
4131 devs_increment = btrfs_raid_array[index].devs_increment;
4132 ncopies = btrfs_raid_array[index].ncopies;
4133
4134 if (type & BTRFS_BLOCK_GROUP_DATA) {
4135 max_stripe_size = 1024 * 1024 * 1024;
4136 max_chunk_size = 10 * max_stripe_size;
4137 if (!devs_max)
4138 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4139 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
4140 /* for larger filesystems, use larger metadata chunks */
4141 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
4142 max_stripe_size = 1024 * 1024 * 1024;
4143 else
4144 max_stripe_size = 256 * 1024 * 1024;
4145 max_chunk_size = max_stripe_size;
4146 if (!devs_max)
4147 devs_max = BTRFS_MAX_DEVS(info->chunk_root);
4148 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
4149 max_stripe_size = 32 * 1024 * 1024;
4150 max_chunk_size = 2 * max_stripe_size;
4151 if (!devs_max)
4152 devs_max = BTRFS_MAX_DEVS_SYS_CHUNK;
4153 } else {
4154 btrfs_err(info, "invalid chunk type 0x%llx requested",
4155 type);
4156 BUG_ON(1);
4157 }
4158
4159 /* we don't want a chunk larger than 10% of writeable space */
4160 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
4161 max_chunk_size);
4162
4163 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices,
4164 GFP_NOFS);
4165 if (!devices_info)
4166 return -ENOMEM;
4167
4168 cur = fs_devices->alloc_list.next;
4169
4170 /*
4171 * in the first pass through the devices list, we gather information
4172 * about the available holes on each device.
4173 */
4174 ndevs = 0;
4175 while (cur != &fs_devices->alloc_list) {
4176 struct btrfs_device *device;
4177 u64 max_avail;
4178 u64 dev_offset;
4179
4180 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
4181
4182 cur = cur->next;
4183
4184 if (!device->writeable) {
4185 WARN(1, KERN_ERR
4186 "BTRFS: read-only device in alloc_list\n");
4187 continue;
4188 }
4189
4190 if (!device->in_fs_metadata ||
4191 device->is_tgtdev_for_dev_replace)
4192 continue;
4193
4194 if (device->total_bytes > device->bytes_used)
4195 total_avail = device->total_bytes - device->bytes_used;
4196 else
4197 total_avail = 0;
4198
4199 /* If there is no space on this device, skip it. */
4200 if (total_avail == 0)
4201 continue;
4202
4203 ret = find_free_dev_extent(trans, device,
4204 max_stripe_size * dev_stripes,
4205 &dev_offset, &max_avail);
4206 if (ret && ret != -ENOSPC)
4207 goto error;
4208
4209 if (ret == 0)
4210 max_avail = max_stripe_size * dev_stripes;
4211
4212 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
4213 continue;
4214
4215 if (ndevs == fs_devices->rw_devices) {
4216 WARN(1, "%s: found more than %llu devices\n",
4217 __func__, fs_devices->rw_devices);
4218 break;
4219 }
4220 devices_info[ndevs].dev_offset = dev_offset;
4221 devices_info[ndevs].max_avail = max_avail;
4222 devices_info[ndevs].total_avail = total_avail;
4223 devices_info[ndevs].dev = device;
4224 ++ndevs;
4225 }
4226
4227 /*
4228 * now sort the devices by hole size / available space
4229 */
4230 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
4231 btrfs_cmp_device_info, NULL);
4232
4233 /* round down to number of usable stripes */
4234 ndevs -= ndevs % devs_increment;
4235
4236 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
4237 ret = -ENOSPC;
4238 goto error;
4239 }
4240
4241 if (devs_max && ndevs > devs_max)
4242 ndevs = devs_max;
4243 /*
4244 * the primary goal is to maximize the number of stripes, so use as many
4245 * devices as possible, even if the stripes are not maximum sized.
4246 */
4247 stripe_size = devices_info[ndevs-1].max_avail;
4248 num_stripes = ndevs * dev_stripes;
4249
4250 /*
4251 * this will have to be fixed for RAID1 and RAID10 over
4252 * more drives
4253 */
4254 data_stripes = num_stripes / ncopies;
4255
4256 if (type & BTRFS_BLOCK_GROUP_RAID5) {
4257 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
4258 btrfs_super_stripesize(info->super_copy));
4259 data_stripes = num_stripes - 1;
4260 }
4261 if (type & BTRFS_BLOCK_GROUP_RAID6) {
4262 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
4263 btrfs_super_stripesize(info->super_copy));
4264 data_stripes = num_stripes - 2;
4265 }
4266
4267 /*
4268 * Use the number of data stripes to figure out how big this chunk
4269 * is really going to be in terms of logical address space,
4270 * and compare that answer with the max chunk size
4271 */
4272 if (stripe_size * data_stripes > max_chunk_size) {
4273 u64 mask = (1ULL << 24) - 1;
4274 stripe_size = max_chunk_size;
4275 do_div(stripe_size, data_stripes);
4276
4277 /* bump the answer up to a 16MB boundary */
4278 stripe_size = (stripe_size + mask) & ~mask;
4279
4280 /* but don't go higher than the limits we found
4281 * while searching for free extents
4282 */
4283 if (stripe_size > devices_info[ndevs-1].max_avail)
4284 stripe_size = devices_info[ndevs-1].max_avail;
4285 }
4286
4287 do_div(stripe_size, dev_stripes);
4288
4289 /* align to BTRFS_STRIPE_LEN */
4290 do_div(stripe_size, raid_stripe_len);
4291 stripe_size *= raid_stripe_len;
4292
4293 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4294 if (!map) {
4295 ret = -ENOMEM;
4296 goto error;
4297 }
4298 map->num_stripes = num_stripes;
4299
4300 for (i = 0; i < ndevs; ++i) {
4301 for (j = 0; j < dev_stripes; ++j) {
4302 int s = i * dev_stripes + j;
4303 map->stripes[s].dev = devices_info[i].dev;
4304 map->stripes[s].physical = devices_info[i].dev_offset +
4305 j * stripe_size;
4306 }
4307 }
4308 map->sector_size = extent_root->sectorsize;
4309 map->stripe_len = raid_stripe_len;
4310 map->io_align = raid_stripe_len;
4311 map->io_width = raid_stripe_len;
4312 map->type = type;
4313 map->sub_stripes = sub_stripes;
4314
4315 num_bytes = stripe_size * data_stripes;
4316
4317 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
4318
4319 em = alloc_extent_map();
4320 if (!em) {
4321 kfree(map);
4322 ret = -ENOMEM;
4323 goto error;
4324 }
4325 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
4326 em->bdev = (struct block_device *)map;
4327 em->start = start;
4328 em->len = num_bytes;
4329 em->block_start = 0;
4330 em->block_len = em->len;
4331 em->orig_block_len = stripe_size;
4332
4333 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4334 write_lock(&em_tree->lock);
4335 ret = add_extent_mapping(em_tree, em, 0);
4336 if (!ret) {
4337 list_add_tail(&em->list, &trans->transaction->pending_chunks);
4338 atomic_inc(&em->refs);
4339 }
4340 write_unlock(&em_tree->lock);
4341 if (ret) {
4342 free_extent_map(em);
4343 goto error;
4344 }
4345
4346 ret = btrfs_make_block_group(trans, extent_root, 0, type,
4347 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4348 start, num_bytes);
4349 if (ret)
4350 goto error_del_extent;
4351
4352 free_extent_map(em);
4353 check_raid56_incompat_flag(extent_root->fs_info, type);
4354
4355 kfree(devices_info);
4356 return 0;
4357
4358 error_del_extent:
4359 write_lock(&em_tree->lock);
4360 remove_extent_mapping(em_tree, em);
4361 write_unlock(&em_tree->lock);
4362
4363 /* One for our allocation */
4364 free_extent_map(em);
4365 /* One for the tree reference */
4366 free_extent_map(em);
4367 error:
4368 kfree(devices_info);
4369 return ret;
4370 }
4371
4372 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans,
4373 struct btrfs_root *extent_root,
4374 u64 chunk_offset, u64 chunk_size)
4375 {
4376 struct btrfs_key key;
4377 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
4378 struct btrfs_device *device;
4379 struct btrfs_chunk *chunk;
4380 struct btrfs_stripe *stripe;
4381 struct extent_map_tree *em_tree;
4382 struct extent_map *em;
4383 struct map_lookup *map;
4384 size_t item_size;
4385 u64 dev_offset;
4386 u64 stripe_size;
4387 int i = 0;
4388 int ret;
4389
4390 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
4391 read_lock(&em_tree->lock);
4392 em = lookup_extent_mapping(em_tree, chunk_offset, chunk_size);
4393 read_unlock(&em_tree->lock);
4394
4395 if (!em) {
4396 btrfs_crit(extent_root->fs_info, "unable to find logical "
4397 "%Lu len %Lu", chunk_offset, chunk_size);
4398 return -EINVAL;
4399 }
4400
4401 if (em->start != chunk_offset || em->len != chunk_size) {
4402 btrfs_crit(extent_root->fs_info, "found a bad mapping, wanted"
4403 " %Lu-%Lu, found %Lu-%Lu", chunk_offset,
4404 chunk_size, em->start, em->len);
4405 free_extent_map(em);
4406 return -EINVAL;
4407 }
4408
4409 map = (struct map_lookup *)em->bdev;
4410 item_size = btrfs_chunk_item_size(map->num_stripes);
4411 stripe_size = em->orig_block_len;
4412
4413 chunk = kzalloc(item_size, GFP_NOFS);
4414 if (!chunk) {
4415 ret = -ENOMEM;
4416 goto out;
4417 }
4418
4419 for (i = 0; i < map->num_stripes; i++) {
4420 device = map->stripes[i].dev;
4421 dev_offset = map->stripes[i].physical;
4422
4423 device->bytes_used += stripe_size;
4424 ret = btrfs_update_device(trans, device);
4425 if (ret)
4426 goto out;
4427 ret = btrfs_alloc_dev_extent(trans, device,
4428 chunk_root->root_key.objectid,
4429 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
4430 chunk_offset, dev_offset,
4431 stripe_size);
4432 if (ret)
4433 goto out;
4434 }
4435
4436 spin_lock(&extent_root->fs_info->free_chunk_lock);
4437 extent_root->fs_info->free_chunk_space -= (stripe_size *
4438 map->num_stripes);
4439 spin_unlock(&extent_root->fs_info->free_chunk_lock);
4440
4441 stripe = &chunk->stripe;
4442 for (i = 0; i < map->num_stripes; i++) {
4443 device = map->stripes[i].dev;
4444 dev_offset = map->stripes[i].physical;
4445
4446 btrfs_set_stack_stripe_devid(stripe, device->devid);
4447 btrfs_set_stack_stripe_offset(stripe, dev_offset);
4448 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
4449 stripe++;
4450 }
4451
4452 btrfs_set_stack_chunk_length(chunk, chunk_size);
4453 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
4454 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
4455 btrfs_set_stack_chunk_type(chunk, map->type);
4456 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
4457 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
4458 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
4459 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
4460 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
4461
4462 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
4463 key.type = BTRFS_CHUNK_ITEM_KEY;
4464 key.offset = chunk_offset;
4465
4466 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
4467 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
4468 /*
4469 * TODO: Cleanup of inserted chunk root in case of
4470 * failure.
4471 */
4472 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
4473 item_size);
4474 }
4475
4476 out:
4477 kfree(chunk);
4478 free_extent_map(em);
4479 return ret;
4480 }
4481
4482 /*
4483 * Chunk allocation falls into two parts. The first part does works
4484 * that make the new allocated chunk useable, but not do any operation
4485 * that modifies the chunk tree. The second part does the works that
4486 * require modifying the chunk tree. This division is important for the
4487 * bootstrap process of adding storage to a seed btrfs.
4488 */
4489 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
4490 struct btrfs_root *extent_root, u64 type)
4491 {
4492 u64 chunk_offset;
4493
4494 chunk_offset = find_next_chunk(extent_root->fs_info);
4495 return __btrfs_alloc_chunk(trans, extent_root, chunk_offset, type);
4496 }
4497
4498 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
4499 struct btrfs_root *root,
4500 struct btrfs_device *device)
4501 {
4502 u64 chunk_offset;
4503 u64 sys_chunk_offset;
4504 u64 alloc_profile;
4505 struct btrfs_fs_info *fs_info = root->fs_info;
4506 struct btrfs_root *extent_root = fs_info->extent_root;
4507 int ret;
4508
4509 chunk_offset = find_next_chunk(fs_info);
4510 alloc_profile = btrfs_get_alloc_profile(extent_root, 0);
4511 ret = __btrfs_alloc_chunk(trans, extent_root, chunk_offset,
4512 alloc_profile);
4513 if (ret)
4514 return ret;
4515
4516 sys_chunk_offset = find_next_chunk(root->fs_info);
4517 alloc_profile = btrfs_get_alloc_profile(fs_info->chunk_root, 0);
4518 ret = __btrfs_alloc_chunk(trans, extent_root, sys_chunk_offset,
4519 alloc_profile);
4520 if (ret) {
4521 btrfs_abort_transaction(trans, root, ret);
4522 goto out;
4523 }
4524
4525 ret = btrfs_add_device(trans, fs_info->chunk_root, device);
4526 if (ret)
4527 btrfs_abort_transaction(trans, root, ret);
4528 out:
4529 return ret;
4530 }
4531
4532 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
4533 {
4534 struct extent_map *em;
4535 struct map_lookup *map;
4536 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4537 int readonly = 0;
4538 int i;
4539
4540 read_lock(&map_tree->map_tree.lock);
4541 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
4542 read_unlock(&map_tree->map_tree.lock);
4543 if (!em)
4544 return 1;
4545
4546 if (btrfs_test_opt(root, DEGRADED)) {
4547 free_extent_map(em);
4548 return 0;
4549 }
4550
4551 map = (struct map_lookup *)em->bdev;
4552 for (i = 0; i < map->num_stripes; i++) {
4553 if (!map->stripes[i].dev->writeable) {
4554 readonly = 1;
4555 break;
4556 }
4557 }
4558 free_extent_map(em);
4559 return readonly;
4560 }
4561
4562 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
4563 {
4564 extent_map_tree_init(&tree->map_tree);
4565 }
4566
4567 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
4568 {
4569 struct extent_map *em;
4570
4571 while (1) {
4572 write_lock(&tree->map_tree.lock);
4573 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
4574 if (em)
4575 remove_extent_mapping(&tree->map_tree, em);
4576 write_unlock(&tree->map_tree.lock);
4577 if (!em)
4578 break;
4579 /* once for us */
4580 free_extent_map(em);
4581 /* once for the tree */
4582 free_extent_map(em);
4583 }
4584 }
4585
4586 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
4587 {
4588 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4589 struct extent_map *em;
4590 struct map_lookup *map;
4591 struct extent_map_tree *em_tree = &map_tree->map_tree;
4592 int ret;
4593
4594 read_lock(&em_tree->lock);
4595 em = lookup_extent_mapping(em_tree, logical, len);
4596 read_unlock(&em_tree->lock);
4597
4598 /*
4599 * We could return errors for these cases, but that could get ugly and
4600 * we'd probably do the same thing which is just not do anything else
4601 * and exit, so return 1 so the callers don't try to use other copies.
4602 */
4603 if (!em) {
4604 btrfs_crit(fs_info, "No mapping for %Lu-%Lu", logical,
4605 logical+len);
4606 return 1;
4607 }
4608
4609 if (em->start > logical || em->start + em->len < logical) {
4610 btrfs_crit(fs_info, "Invalid mapping for %Lu-%Lu, got "
4611 "%Lu-%Lu", logical, logical+len, em->start,
4612 em->start + em->len);
4613 free_extent_map(em);
4614 return 1;
4615 }
4616
4617 map = (struct map_lookup *)em->bdev;
4618 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
4619 ret = map->num_stripes;
4620 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
4621 ret = map->sub_stripes;
4622 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
4623 ret = 2;
4624 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
4625 ret = 3;
4626 else
4627 ret = 1;
4628 free_extent_map(em);
4629
4630 btrfs_dev_replace_lock(&fs_info->dev_replace);
4631 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
4632 ret++;
4633 btrfs_dev_replace_unlock(&fs_info->dev_replace);
4634
4635 return ret;
4636 }
4637
4638 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
4639 struct btrfs_mapping_tree *map_tree,
4640 u64 logical)
4641 {
4642 struct extent_map *em;
4643 struct map_lookup *map;
4644 struct extent_map_tree *em_tree = &map_tree->map_tree;
4645 unsigned long len = root->sectorsize;
4646
4647 read_lock(&em_tree->lock);
4648 em = lookup_extent_mapping(em_tree, logical, len);
4649 read_unlock(&em_tree->lock);
4650 BUG_ON(!em);
4651
4652 BUG_ON(em->start > logical || em->start + em->len < logical);
4653 map = (struct map_lookup *)em->bdev;
4654 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
4655 BTRFS_BLOCK_GROUP_RAID6)) {
4656 len = map->stripe_len * nr_data_stripes(map);
4657 }
4658 free_extent_map(em);
4659 return len;
4660 }
4661
4662 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
4663 u64 logical, u64 len, int mirror_num)
4664 {
4665 struct extent_map *em;
4666 struct map_lookup *map;
4667 struct extent_map_tree *em_tree = &map_tree->map_tree;
4668 int ret = 0;
4669
4670 read_lock(&em_tree->lock);
4671 em = lookup_extent_mapping(em_tree, logical, len);
4672 read_unlock(&em_tree->lock);
4673 BUG_ON(!em);
4674
4675 BUG_ON(em->start > logical || em->start + em->len < logical);
4676 map = (struct map_lookup *)em->bdev;
4677 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
4678 BTRFS_BLOCK_GROUP_RAID6))
4679 ret = 1;
4680 free_extent_map(em);
4681 return ret;
4682 }
4683
4684 static int find_live_mirror(struct btrfs_fs_info *fs_info,
4685 struct map_lookup *map, int first, int num,
4686 int optimal, int dev_replace_is_ongoing)
4687 {
4688 int i;
4689 int tolerance;
4690 struct btrfs_device *srcdev;
4691
4692 if (dev_replace_is_ongoing &&
4693 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
4694 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
4695 srcdev = fs_info->dev_replace.srcdev;
4696 else
4697 srcdev = NULL;
4698
4699 /*
4700 * try to avoid the drive that is the source drive for a
4701 * dev-replace procedure, only choose it if no other non-missing
4702 * mirror is available
4703 */
4704 for (tolerance = 0; tolerance < 2; tolerance++) {
4705 if (map->stripes[optimal].dev->bdev &&
4706 (tolerance || map->stripes[optimal].dev != srcdev))
4707 return optimal;
4708 for (i = first; i < first + num; i++) {
4709 if (map->stripes[i].dev->bdev &&
4710 (tolerance || map->stripes[i].dev != srcdev))
4711 return i;
4712 }
4713 }
4714
4715 /* we couldn't find one that doesn't fail. Just return something
4716 * and the io error handling code will clean up eventually
4717 */
4718 return optimal;
4719 }
4720
4721 static inline int parity_smaller(u64 a, u64 b)
4722 {
4723 return a > b;
4724 }
4725
4726 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
4727 static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map)
4728 {
4729 struct btrfs_bio_stripe s;
4730 int i;
4731 u64 l;
4732 int again = 1;
4733
4734 while (again) {
4735 again = 0;
4736 for (i = 0; i < bbio->num_stripes - 1; i++) {
4737 if (parity_smaller(raid_map[i], raid_map[i+1])) {
4738 s = bbio->stripes[i];
4739 l = raid_map[i];
4740 bbio->stripes[i] = bbio->stripes[i+1];
4741 raid_map[i] = raid_map[i+1];
4742 bbio->stripes[i+1] = s;
4743 raid_map[i+1] = l;
4744 again = 1;
4745 }
4746 }
4747 }
4748 }
4749
4750 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
4751 u64 logical, u64 *length,
4752 struct btrfs_bio **bbio_ret,
4753 int mirror_num, u64 **raid_map_ret)
4754 {
4755 struct extent_map *em;
4756 struct map_lookup *map;
4757 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4758 struct extent_map_tree *em_tree = &map_tree->map_tree;
4759 u64 offset;
4760 u64 stripe_offset;
4761 u64 stripe_end_offset;
4762 u64 stripe_nr;
4763 u64 stripe_nr_orig;
4764 u64 stripe_nr_end;
4765 u64 stripe_len;
4766 u64 *raid_map = NULL;
4767 int stripe_index;
4768 int i;
4769 int ret = 0;
4770 int num_stripes;
4771 int max_errors = 0;
4772 struct btrfs_bio *bbio = NULL;
4773 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
4774 int dev_replace_is_ongoing = 0;
4775 int num_alloc_stripes;
4776 int patch_the_first_stripe_for_dev_replace = 0;
4777 u64 physical_to_patch_in_first_stripe = 0;
4778 u64 raid56_full_stripe_start = (u64)-1;
4779
4780 read_lock(&em_tree->lock);
4781 em = lookup_extent_mapping(em_tree, logical, *length);
4782 read_unlock(&em_tree->lock);
4783
4784 if (!em) {
4785 btrfs_crit(fs_info, "unable to find logical %llu len %llu",
4786 logical, *length);
4787 return -EINVAL;
4788 }
4789
4790 if (em->start > logical || em->start + em->len < logical) {
4791 btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, "
4792 "found %Lu-%Lu", logical, em->start,
4793 em->start + em->len);
4794 free_extent_map(em);
4795 return -EINVAL;
4796 }
4797
4798 map = (struct map_lookup *)em->bdev;
4799 offset = logical - em->start;
4800
4801 stripe_len = map->stripe_len;
4802 stripe_nr = offset;
4803 /*
4804 * stripe_nr counts the total number of stripes we have to stride
4805 * to get to this block
4806 */
4807 do_div(stripe_nr, stripe_len);
4808
4809 stripe_offset = stripe_nr * stripe_len;
4810 BUG_ON(offset < stripe_offset);
4811
4812 /* stripe_offset is the offset of this block in its stripe*/
4813 stripe_offset = offset - stripe_offset;
4814
4815 /* if we're here for raid56, we need to know the stripe aligned start */
4816 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) {
4817 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
4818 raid56_full_stripe_start = offset;
4819
4820 /* allow a write of a full stripe, but make sure we don't
4821 * allow straddling of stripes
4822 */
4823 do_div(raid56_full_stripe_start, full_stripe_len);
4824 raid56_full_stripe_start *= full_stripe_len;
4825 }
4826
4827 if (rw & REQ_DISCARD) {
4828 /* we don't discard raid56 yet */
4829 if (map->type &
4830 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) {
4831 ret = -EOPNOTSUPP;
4832 goto out;
4833 }
4834 *length = min_t(u64, em->len - offset, *length);
4835 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
4836 u64 max_len;
4837 /* For writes to RAID[56], allow a full stripeset across all disks.
4838 For other RAID types and for RAID[56] reads, just allow a single
4839 stripe (on a single disk). */
4840 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6) &&
4841 (rw & REQ_WRITE)) {
4842 max_len = stripe_len * nr_data_stripes(map) -
4843 (offset - raid56_full_stripe_start);
4844 } else {
4845 /* we limit the length of each bio to what fits in a stripe */
4846 max_len = stripe_len - stripe_offset;
4847 }
4848 *length = min_t(u64, em->len - offset, max_len);
4849 } else {
4850 *length = em->len - offset;
4851 }
4852
4853 /* This is for when we're called from btrfs_merge_bio_hook() and all
4854 it cares about is the length */
4855 if (!bbio_ret)
4856 goto out;
4857
4858 btrfs_dev_replace_lock(dev_replace);
4859 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
4860 if (!dev_replace_is_ongoing)
4861 btrfs_dev_replace_unlock(dev_replace);
4862
4863 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
4864 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
4865 dev_replace->tgtdev != NULL) {
4866 /*
4867 * in dev-replace case, for repair case (that's the only
4868 * case where the mirror is selected explicitly when
4869 * calling btrfs_map_block), blocks left of the left cursor
4870 * can also be read from the target drive.
4871 * For REQ_GET_READ_MIRRORS, the target drive is added as
4872 * the last one to the array of stripes. For READ, it also
4873 * needs to be supported using the same mirror number.
4874 * If the requested block is not left of the left cursor,
4875 * EIO is returned. This can happen because btrfs_num_copies()
4876 * returns one more in the dev-replace case.
4877 */
4878 u64 tmp_length = *length;
4879 struct btrfs_bio *tmp_bbio = NULL;
4880 int tmp_num_stripes;
4881 u64 srcdev_devid = dev_replace->srcdev->devid;
4882 int index_srcdev = 0;
4883 int found = 0;
4884 u64 physical_of_found = 0;
4885
4886 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
4887 logical, &tmp_length, &tmp_bbio, 0, NULL);
4888 if (ret) {
4889 WARN_ON(tmp_bbio != NULL);
4890 goto out;
4891 }
4892
4893 tmp_num_stripes = tmp_bbio->num_stripes;
4894 if (mirror_num > tmp_num_stripes) {
4895 /*
4896 * REQ_GET_READ_MIRRORS does not contain this
4897 * mirror, that means that the requested area
4898 * is not left of the left cursor
4899 */
4900 ret = -EIO;
4901 kfree(tmp_bbio);
4902 goto out;
4903 }
4904
4905 /*
4906 * process the rest of the function using the mirror_num
4907 * of the source drive. Therefore look it up first.
4908 * At the end, patch the device pointer to the one of the
4909 * target drive.
4910 */
4911 for (i = 0; i < tmp_num_stripes; i++) {
4912 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) {
4913 /*
4914 * In case of DUP, in order to keep it
4915 * simple, only add the mirror with the
4916 * lowest physical address
4917 */
4918 if (found &&
4919 physical_of_found <=
4920 tmp_bbio->stripes[i].physical)
4921 continue;
4922 index_srcdev = i;
4923 found = 1;
4924 physical_of_found =
4925 tmp_bbio->stripes[i].physical;
4926 }
4927 }
4928
4929 if (found) {
4930 mirror_num = index_srcdev + 1;
4931 patch_the_first_stripe_for_dev_replace = 1;
4932 physical_to_patch_in_first_stripe = physical_of_found;
4933 } else {
4934 WARN_ON(1);
4935 ret = -EIO;
4936 kfree(tmp_bbio);
4937 goto out;
4938 }
4939
4940 kfree(tmp_bbio);
4941 } else if (mirror_num > map->num_stripes) {
4942 mirror_num = 0;
4943 }
4944
4945 num_stripes = 1;
4946 stripe_index = 0;
4947 stripe_nr_orig = stripe_nr;
4948 stripe_nr_end = ALIGN(offset + *length, map->stripe_len);
4949 do_div(stripe_nr_end, map->stripe_len);
4950 stripe_end_offset = stripe_nr_end * map->stripe_len -
4951 (offset + *length);
4952
4953 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
4954 if (rw & REQ_DISCARD)
4955 num_stripes = min_t(u64, map->num_stripes,
4956 stripe_nr_end - stripe_nr_orig);
4957 stripe_index = do_div(stripe_nr, map->num_stripes);
4958 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
4959 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
4960 num_stripes = map->num_stripes;
4961 else if (mirror_num)
4962 stripe_index = mirror_num - 1;
4963 else {
4964 stripe_index = find_live_mirror(fs_info, map, 0,
4965 map->num_stripes,
4966 current->pid % map->num_stripes,
4967 dev_replace_is_ongoing);
4968 mirror_num = stripe_index + 1;
4969 }
4970
4971 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
4972 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
4973 num_stripes = map->num_stripes;
4974 } else if (mirror_num) {
4975 stripe_index = mirror_num - 1;
4976 } else {
4977 mirror_num = 1;
4978 }
4979
4980 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
4981 int factor = map->num_stripes / map->sub_stripes;
4982
4983 stripe_index = do_div(stripe_nr, factor);
4984 stripe_index *= map->sub_stripes;
4985
4986 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
4987 num_stripes = map->sub_stripes;
4988 else if (rw & REQ_DISCARD)
4989 num_stripes = min_t(u64, map->sub_stripes *
4990 (stripe_nr_end - stripe_nr_orig),
4991 map->num_stripes);
4992 else if (mirror_num)
4993 stripe_index += mirror_num - 1;
4994 else {
4995 int old_stripe_index = stripe_index;
4996 stripe_index = find_live_mirror(fs_info, map,
4997 stripe_index,
4998 map->sub_stripes, stripe_index +
4999 current->pid % map->sub_stripes,
5000 dev_replace_is_ongoing);
5001 mirror_num = stripe_index - old_stripe_index + 1;
5002 }
5003
5004 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
5005 BTRFS_BLOCK_GROUP_RAID6)) {
5006 u64 tmp;
5007
5008 if (bbio_ret && ((rw & REQ_WRITE) || mirror_num > 1)
5009 && raid_map_ret) {
5010 int i, rot;
5011
5012 /* push stripe_nr back to the start of the full stripe */
5013 stripe_nr = raid56_full_stripe_start;
5014 do_div(stripe_nr, stripe_len);
5015
5016 stripe_index = do_div(stripe_nr, nr_data_stripes(map));
5017
5018 /* RAID[56] write or recovery. Return all stripes */
5019 num_stripes = map->num_stripes;
5020 max_errors = nr_parity_stripes(map);
5021
5022 raid_map = kmalloc_array(num_stripes, sizeof(u64),
5023 GFP_NOFS);
5024 if (!raid_map) {
5025 ret = -ENOMEM;
5026 goto out;
5027 }
5028
5029 /* Work out the disk rotation on this stripe-set */
5030 tmp = stripe_nr;
5031 rot = do_div(tmp, num_stripes);
5032
5033 /* Fill in the logical address of each stripe */
5034 tmp = stripe_nr * nr_data_stripes(map);
5035 for (i = 0; i < nr_data_stripes(map); i++)
5036 raid_map[(i+rot) % num_stripes] =
5037 em->start + (tmp + i) * map->stripe_len;
5038
5039 raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
5040 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
5041 raid_map[(i+rot+1) % num_stripes] =
5042 RAID6_Q_STRIPE;
5043
5044 *length = map->stripe_len;
5045 stripe_index = 0;
5046 stripe_offset = 0;
5047 } else {
5048 /*
5049 * Mirror #0 or #1 means the original data block.
5050 * Mirror #2 is RAID5 parity block.
5051 * Mirror #3 is RAID6 Q block.
5052 */
5053 stripe_index = do_div(stripe_nr, nr_data_stripes(map));
5054 if (mirror_num > 1)
5055 stripe_index = nr_data_stripes(map) +
5056 mirror_num - 2;
5057
5058 /* We distribute the parity blocks across stripes */
5059 tmp = stripe_nr + stripe_index;
5060 stripe_index = do_div(tmp, map->num_stripes);
5061 }
5062 } else {
5063 /*
5064 * after this do_div call, stripe_nr is the number of stripes
5065 * on this device we have to walk to find the data, and
5066 * stripe_index is the number of our device in the stripe array
5067 */
5068 stripe_index = do_div(stripe_nr, map->num_stripes);
5069 mirror_num = stripe_index + 1;
5070 }
5071 BUG_ON(stripe_index >= map->num_stripes);
5072
5073 num_alloc_stripes = num_stripes;
5074 if (dev_replace_is_ongoing) {
5075 if (rw & (REQ_WRITE | REQ_DISCARD))
5076 num_alloc_stripes <<= 1;
5077 if (rw & REQ_GET_READ_MIRRORS)
5078 num_alloc_stripes++;
5079 }
5080 bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS);
5081 if (!bbio) {
5082 kfree(raid_map);
5083 ret = -ENOMEM;
5084 goto out;
5085 }
5086 atomic_set(&bbio->error, 0);
5087
5088 if (rw & REQ_DISCARD) {
5089 int factor = 0;
5090 int sub_stripes = 0;
5091 u64 stripes_per_dev = 0;
5092 u32 remaining_stripes = 0;
5093 u32 last_stripe = 0;
5094
5095 if (map->type &
5096 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
5097 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5098 sub_stripes = 1;
5099 else
5100 sub_stripes = map->sub_stripes;
5101
5102 factor = map->num_stripes / sub_stripes;
5103 stripes_per_dev = div_u64_rem(stripe_nr_end -
5104 stripe_nr_orig,
5105 factor,
5106 &remaining_stripes);
5107 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
5108 last_stripe *= sub_stripes;
5109 }
5110
5111 for (i = 0; i < num_stripes; i++) {
5112 bbio->stripes[i].physical =
5113 map->stripes[stripe_index].physical +
5114 stripe_offset + stripe_nr * map->stripe_len;
5115 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
5116
5117 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
5118 BTRFS_BLOCK_GROUP_RAID10)) {
5119 bbio->stripes[i].length = stripes_per_dev *
5120 map->stripe_len;
5121
5122 if (i / sub_stripes < remaining_stripes)
5123 bbio->stripes[i].length +=
5124 map->stripe_len;
5125
5126 /*
5127 * Special for the first stripe and
5128 * the last stripe:
5129 *
5130 * |-------|...|-------|
5131 * |----------|
5132 * off end_off
5133 */
5134 if (i < sub_stripes)
5135 bbio->stripes[i].length -=
5136 stripe_offset;
5137
5138 if (stripe_index >= last_stripe &&
5139 stripe_index <= (last_stripe +
5140 sub_stripes - 1))
5141 bbio->stripes[i].length -=
5142 stripe_end_offset;
5143
5144 if (i == sub_stripes - 1)
5145 stripe_offset = 0;
5146 } else
5147 bbio->stripes[i].length = *length;
5148
5149 stripe_index++;
5150 if (stripe_index == map->num_stripes) {
5151 /* This could only happen for RAID0/10 */
5152 stripe_index = 0;
5153 stripe_nr++;
5154 }
5155 }
5156 } else {
5157 for (i = 0; i < num_stripes; i++) {
5158 bbio->stripes[i].physical =
5159 map->stripes[stripe_index].physical +
5160 stripe_offset +
5161 stripe_nr * map->stripe_len;
5162 bbio->stripes[i].dev =
5163 map->stripes[stripe_index].dev;
5164 stripe_index++;
5165 }
5166 }
5167
5168 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) {
5169 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
5170 BTRFS_BLOCK_GROUP_RAID10 |
5171 BTRFS_BLOCK_GROUP_RAID5 |
5172 BTRFS_BLOCK_GROUP_DUP)) {
5173 max_errors = 1;
5174 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
5175 max_errors = 2;
5176 }
5177 }
5178
5179 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
5180 dev_replace->tgtdev != NULL) {
5181 int index_where_to_add;
5182 u64 srcdev_devid = dev_replace->srcdev->devid;
5183
5184 /*
5185 * duplicate the write operations while the dev replace
5186 * procedure is running. Since the copying of the old disk
5187 * to the new disk takes place at run time while the
5188 * filesystem is mounted writable, the regular write
5189 * operations to the old disk have to be duplicated to go
5190 * to the new disk as well.
5191 * Note that device->missing is handled by the caller, and
5192 * that the write to the old disk is already set up in the
5193 * stripes array.
5194 */
5195 index_where_to_add = num_stripes;
5196 for (i = 0; i < num_stripes; i++) {
5197 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5198 /* write to new disk, too */
5199 struct btrfs_bio_stripe *new =
5200 bbio->stripes + index_where_to_add;
5201 struct btrfs_bio_stripe *old =
5202 bbio->stripes + i;
5203
5204 new->physical = old->physical;
5205 new->length = old->length;
5206 new->dev = dev_replace->tgtdev;
5207 index_where_to_add++;
5208 max_errors++;
5209 }
5210 }
5211 num_stripes = index_where_to_add;
5212 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
5213 dev_replace->tgtdev != NULL) {
5214 u64 srcdev_devid = dev_replace->srcdev->devid;
5215 int index_srcdev = 0;
5216 int found = 0;
5217 u64 physical_of_found = 0;
5218
5219 /*
5220 * During the dev-replace procedure, the target drive can
5221 * also be used to read data in case it is needed to repair
5222 * a corrupt block elsewhere. This is possible if the
5223 * requested area is left of the left cursor. In this area,
5224 * the target drive is a full copy of the source drive.
5225 */
5226 for (i = 0; i < num_stripes; i++) {
5227 if (bbio->stripes[i].dev->devid == srcdev_devid) {
5228 /*
5229 * In case of DUP, in order to keep it
5230 * simple, only add the mirror with the
5231 * lowest physical address
5232 */
5233 if (found &&
5234 physical_of_found <=
5235 bbio->stripes[i].physical)
5236 continue;
5237 index_srcdev = i;
5238 found = 1;
5239 physical_of_found = bbio->stripes[i].physical;
5240 }
5241 }
5242 if (found) {
5243 u64 length = map->stripe_len;
5244
5245 if (physical_of_found + length <=
5246 dev_replace->cursor_left) {
5247 struct btrfs_bio_stripe *tgtdev_stripe =
5248 bbio->stripes + num_stripes;
5249
5250 tgtdev_stripe->physical = physical_of_found;
5251 tgtdev_stripe->length =
5252 bbio->stripes[index_srcdev].length;
5253 tgtdev_stripe->dev = dev_replace->tgtdev;
5254
5255 num_stripes++;
5256 }
5257 }
5258 }
5259
5260 *bbio_ret = bbio;
5261 bbio->num_stripes = num_stripes;
5262 bbio->max_errors = max_errors;
5263 bbio->mirror_num = mirror_num;
5264
5265 /*
5266 * this is the case that REQ_READ && dev_replace_is_ongoing &&
5267 * mirror_num == num_stripes + 1 && dev_replace target drive is
5268 * available as a mirror
5269 */
5270 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
5271 WARN_ON(num_stripes > 1);
5272 bbio->stripes[0].dev = dev_replace->tgtdev;
5273 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
5274 bbio->mirror_num = map->num_stripes + 1;
5275 }
5276 if (raid_map) {
5277 sort_parity_stripes(bbio, raid_map);
5278 *raid_map_ret = raid_map;
5279 }
5280 out:
5281 if (dev_replace_is_ongoing)
5282 btrfs_dev_replace_unlock(dev_replace);
5283 free_extent_map(em);
5284 return ret;
5285 }
5286
5287 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
5288 u64 logical, u64 *length,
5289 struct btrfs_bio **bbio_ret, int mirror_num)
5290 {
5291 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
5292 mirror_num, NULL);
5293 }
5294
5295 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
5296 u64 chunk_start, u64 physical, u64 devid,
5297 u64 **logical, int *naddrs, int *stripe_len)
5298 {
5299 struct extent_map_tree *em_tree = &map_tree->map_tree;
5300 struct extent_map *em;
5301 struct map_lookup *map;
5302 u64 *buf;
5303 u64 bytenr;
5304 u64 length;
5305 u64 stripe_nr;
5306 u64 rmap_len;
5307 int i, j, nr = 0;
5308
5309 read_lock(&em_tree->lock);
5310 em = lookup_extent_mapping(em_tree, chunk_start, 1);
5311 read_unlock(&em_tree->lock);
5312
5313 if (!em) {
5314 printk(KERN_ERR "BTRFS: couldn't find em for chunk %Lu\n",
5315 chunk_start);
5316 return -EIO;
5317 }
5318
5319 if (em->start != chunk_start) {
5320 printk(KERN_ERR "BTRFS: bad chunk start, em=%Lu, wanted=%Lu\n",
5321 em->start, chunk_start);
5322 free_extent_map(em);
5323 return -EIO;
5324 }
5325 map = (struct map_lookup *)em->bdev;
5326
5327 length = em->len;
5328 rmap_len = map->stripe_len;
5329
5330 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
5331 do_div(length, map->num_stripes / map->sub_stripes);
5332 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
5333 do_div(length, map->num_stripes);
5334 else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
5335 BTRFS_BLOCK_GROUP_RAID6)) {
5336 do_div(length, nr_data_stripes(map));
5337 rmap_len = map->stripe_len * nr_data_stripes(map);
5338 }
5339
5340 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
5341 BUG_ON(!buf); /* -ENOMEM */
5342
5343 for (i = 0; i < map->num_stripes; i++) {
5344 if (devid && map->stripes[i].dev->devid != devid)
5345 continue;
5346 if (map->stripes[i].physical > physical ||
5347 map->stripes[i].physical + length <= physical)
5348 continue;
5349
5350 stripe_nr = physical - map->stripes[i].physical;
5351 do_div(stripe_nr, map->stripe_len);
5352
5353 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
5354 stripe_nr = stripe_nr * map->num_stripes + i;
5355 do_div(stripe_nr, map->sub_stripes);
5356 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
5357 stripe_nr = stripe_nr * map->num_stripes + i;
5358 } /* else if RAID[56], multiply by nr_data_stripes().
5359 * Alternatively, just use rmap_len below instead of
5360 * map->stripe_len */
5361
5362 bytenr = chunk_start + stripe_nr * rmap_len;
5363 WARN_ON(nr >= map->num_stripes);
5364 for (j = 0; j < nr; j++) {
5365 if (buf[j] == bytenr)
5366 break;
5367 }
5368 if (j == nr) {
5369 WARN_ON(nr >= map->num_stripes);
5370 buf[nr++] = bytenr;
5371 }
5372 }
5373
5374 *logical = buf;
5375 *naddrs = nr;
5376 *stripe_len = rmap_len;
5377
5378 free_extent_map(em);
5379 return 0;
5380 }
5381
5382 static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio, int err)
5383 {
5384 if (likely(bbio->flags & BTRFS_BIO_ORIG_BIO_SUBMITTED))
5385 bio_endio_nodec(bio, err);
5386 else
5387 bio_endio(bio, err);
5388 kfree(bbio);
5389 }
5390
5391 static void btrfs_end_bio(struct bio *bio, int err)
5392 {
5393 struct btrfs_bio *bbio = bio->bi_private;
5394 struct btrfs_device *dev = bbio->stripes[0].dev;
5395 int is_orig_bio = 0;
5396
5397 if (err) {
5398 atomic_inc(&bbio->error);
5399 if (err == -EIO || err == -EREMOTEIO) {
5400 unsigned int stripe_index =
5401 btrfs_io_bio(bio)->stripe_index;
5402
5403 BUG_ON(stripe_index >= bbio->num_stripes);
5404 dev = bbio->stripes[stripe_index].dev;
5405 if (dev->bdev) {
5406 if (bio->bi_rw & WRITE)
5407 btrfs_dev_stat_inc(dev,
5408 BTRFS_DEV_STAT_WRITE_ERRS);
5409 else
5410 btrfs_dev_stat_inc(dev,
5411 BTRFS_DEV_STAT_READ_ERRS);
5412 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
5413 btrfs_dev_stat_inc(dev,
5414 BTRFS_DEV_STAT_FLUSH_ERRS);
5415 btrfs_dev_stat_print_on_error(dev);
5416 }
5417 }
5418 }
5419
5420 if (bio == bbio->orig_bio)
5421 is_orig_bio = 1;
5422
5423 btrfs_bio_counter_dec(bbio->fs_info);
5424
5425 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5426 if (!is_orig_bio) {
5427 bio_put(bio);
5428 bio = bbio->orig_bio;
5429 }
5430
5431 bio->bi_private = bbio->private;
5432 bio->bi_end_io = bbio->end_io;
5433 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5434 /* only send an error to the higher layers if it is
5435 * beyond the tolerance of the btrfs bio
5436 */
5437 if (atomic_read(&bbio->error) > bbio->max_errors) {
5438 err = -EIO;
5439 } else {
5440 /*
5441 * this bio is actually up to date, we didn't
5442 * go over the max number of errors
5443 */
5444 set_bit(BIO_UPTODATE, &bio->bi_flags);
5445 err = 0;
5446 }
5447
5448 btrfs_end_bbio(bbio, bio, err);
5449 } else if (!is_orig_bio) {
5450 bio_put(bio);
5451 }
5452 }
5453
5454 /*
5455 * see run_scheduled_bios for a description of why bios are collected for
5456 * async submit.
5457 *
5458 * This will add one bio to the pending list for a device and make sure
5459 * the work struct is scheduled.
5460 */
5461 static noinline void btrfs_schedule_bio(struct btrfs_root *root,
5462 struct btrfs_device *device,
5463 int rw, struct bio *bio)
5464 {
5465 int should_queue = 1;
5466 struct btrfs_pending_bios *pending_bios;
5467
5468 if (device->missing || !device->bdev) {
5469 bio_endio(bio, -EIO);
5470 return;
5471 }
5472
5473 /* don't bother with additional async steps for reads, right now */
5474 if (!(rw & REQ_WRITE)) {
5475 bio_get(bio);
5476 btrfsic_submit_bio(rw, bio);
5477 bio_put(bio);
5478 return;
5479 }
5480
5481 /*
5482 * nr_async_bios allows us to reliably return congestion to the
5483 * higher layers. Otherwise, the async bio makes it appear we have
5484 * made progress against dirty pages when we've really just put it
5485 * on a queue for later
5486 */
5487 atomic_inc(&root->fs_info->nr_async_bios);
5488 WARN_ON(bio->bi_next);
5489 bio->bi_next = NULL;
5490 bio->bi_rw |= rw;
5491
5492 spin_lock(&device->io_lock);
5493 if (bio->bi_rw & REQ_SYNC)
5494 pending_bios = &device->pending_sync_bios;
5495 else
5496 pending_bios = &device->pending_bios;
5497
5498 if (pending_bios->tail)
5499 pending_bios->tail->bi_next = bio;
5500
5501 pending_bios->tail = bio;
5502 if (!pending_bios->head)
5503 pending_bios->head = bio;
5504 if (device->running_pending)
5505 should_queue = 0;
5506
5507 spin_unlock(&device->io_lock);
5508
5509 if (should_queue)
5510 btrfs_queue_work(root->fs_info->submit_workers,
5511 &device->work);
5512 }
5513
5514 static int bio_size_ok(struct block_device *bdev, struct bio *bio,
5515 sector_t sector)
5516 {
5517 struct bio_vec *prev;
5518 struct request_queue *q = bdev_get_queue(bdev);
5519 unsigned int max_sectors = queue_max_sectors(q);
5520 struct bvec_merge_data bvm = {
5521 .bi_bdev = bdev,
5522 .bi_sector = sector,
5523 .bi_rw = bio->bi_rw,
5524 };
5525
5526 if (WARN_ON(bio->bi_vcnt == 0))
5527 return 1;
5528
5529 prev = &bio->bi_io_vec[bio->bi_vcnt - 1];
5530 if (bio_sectors(bio) > max_sectors)
5531 return 0;
5532
5533 if (!q->merge_bvec_fn)
5534 return 1;
5535
5536 bvm.bi_size = bio->bi_iter.bi_size - prev->bv_len;
5537 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len)
5538 return 0;
5539 return 1;
5540 }
5541
5542 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5543 struct bio *bio, u64 physical, int dev_nr,
5544 int rw, int async)
5545 {
5546 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
5547
5548 bio->bi_private = bbio;
5549 btrfs_io_bio(bio)->stripe_index = dev_nr;
5550 bio->bi_end_io = btrfs_end_bio;
5551 bio->bi_iter.bi_sector = physical >> 9;
5552 #ifdef DEBUG
5553 {
5554 struct rcu_string *name;
5555
5556 rcu_read_lock();
5557 name = rcu_dereference(dev->name);
5558 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
5559 "(%s id %llu), size=%u\n", rw,
5560 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev,
5561 name->str, dev->devid, bio->bi_size);
5562 rcu_read_unlock();
5563 }
5564 #endif
5565 bio->bi_bdev = dev->bdev;
5566
5567 btrfs_bio_counter_inc_noblocked(root->fs_info);
5568
5569 if (async)
5570 btrfs_schedule_bio(root, dev, rw, bio);
5571 else
5572 btrfsic_submit_bio(rw, bio);
5573 }
5574
5575 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5576 struct bio *first_bio, struct btrfs_device *dev,
5577 int dev_nr, int rw, int async)
5578 {
5579 struct bio_vec *bvec = first_bio->bi_io_vec;
5580 struct bio *bio;
5581 int nr_vecs = bio_get_nr_vecs(dev->bdev);
5582 u64 physical = bbio->stripes[dev_nr].physical;
5583
5584 again:
5585 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS);
5586 if (!bio)
5587 return -ENOMEM;
5588
5589 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) {
5590 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5591 bvec->bv_offset) < bvec->bv_len) {
5592 u64 len = bio->bi_iter.bi_size;
5593
5594 atomic_inc(&bbio->stripes_pending);
5595 submit_stripe_bio(root, bbio, bio, physical, dev_nr,
5596 rw, async);
5597 physical += len;
5598 goto again;
5599 }
5600 bvec++;
5601 }
5602
5603 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async);
5604 return 0;
5605 }
5606
5607 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
5608 {
5609 atomic_inc(&bbio->error);
5610 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5611 /* Shoud be the original bio. */
5612 WARN_ON(bio != bbio->orig_bio);
5613
5614 bio->bi_private = bbio->private;
5615 bio->bi_end_io = bbio->end_io;
5616 btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
5617 bio->bi_iter.bi_sector = logical >> 9;
5618
5619 btrfs_end_bbio(bbio, bio, -EIO);
5620 }
5621 }
5622
5623 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
5624 int mirror_num, int async_submit)
5625 {
5626 struct btrfs_device *dev;
5627 struct bio *first_bio = bio;
5628 u64 logical = (u64)bio->bi_iter.bi_sector << 9;
5629 u64 length = 0;
5630 u64 map_length;
5631 u64 *raid_map = NULL;
5632 int ret;
5633 int dev_nr = 0;
5634 int total_devs = 1;
5635 struct btrfs_bio *bbio = NULL;
5636
5637 length = bio->bi_iter.bi_size;
5638 map_length = length;
5639
5640 btrfs_bio_counter_inc_blocked(root->fs_info);
5641 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
5642 mirror_num, &raid_map);
5643 if (ret) {
5644 btrfs_bio_counter_dec(root->fs_info);
5645 return ret;
5646 }
5647
5648 total_devs = bbio->num_stripes;
5649 bbio->orig_bio = first_bio;
5650 bbio->private = first_bio->bi_private;
5651 bbio->end_io = first_bio->bi_end_io;
5652 bbio->fs_info = root->fs_info;
5653 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
5654
5655 if (raid_map) {
5656 /* In this case, map_length has been set to the length of
5657 a single stripe; not the whole write */
5658 if (rw & WRITE) {
5659 ret = raid56_parity_write(root, bio, bbio,
5660 raid_map, map_length);
5661 } else {
5662 ret = raid56_parity_recover(root, bio, bbio,
5663 raid_map, map_length,
5664 mirror_num);
5665 }
5666 /*
5667 * FIXME, replace dosen't support raid56 yet, please fix
5668 * it in the future.
5669 */
5670 btrfs_bio_counter_dec(root->fs_info);
5671 return ret;
5672 }
5673
5674 if (map_length < length) {
5675 btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
5676 logical, length, map_length);
5677 BUG();
5678 }
5679
5680 while (dev_nr < total_devs) {
5681 dev = bbio->stripes[dev_nr].dev;
5682 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
5683 bbio_error(bbio, first_bio, logical);
5684 dev_nr++;
5685 continue;
5686 }
5687
5688 /*
5689 * Check and see if we're ok with this bio based on it's size
5690 * and offset with the given device.
5691 */
5692 if (!bio_size_ok(dev->bdev, first_bio,
5693 bbio->stripes[dev_nr].physical >> 9)) {
5694 ret = breakup_stripe_bio(root, bbio, first_bio, dev,
5695 dev_nr, rw, async_submit);
5696 BUG_ON(ret);
5697 dev_nr++;
5698 continue;
5699 }
5700
5701 if (dev_nr < total_devs - 1) {
5702 bio = btrfs_bio_clone(first_bio, GFP_NOFS);
5703 BUG_ON(!bio); /* -ENOMEM */
5704 } else {
5705 bio = first_bio;
5706 bbio->flags |= BTRFS_BIO_ORIG_BIO_SUBMITTED;
5707 }
5708
5709 submit_stripe_bio(root, bbio, bio,
5710 bbio->stripes[dev_nr].physical, dev_nr, rw,
5711 async_submit);
5712 dev_nr++;
5713 }
5714 btrfs_bio_counter_dec(root->fs_info);
5715 return 0;
5716 }
5717
5718 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
5719 u8 *uuid, u8 *fsid)
5720 {
5721 struct btrfs_device *device;
5722 struct btrfs_fs_devices *cur_devices;
5723
5724 cur_devices = fs_info->fs_devices;
5725 while (cur_devices) {
5726 if (!fsid ||
5727 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
5728 device = __find_device(&cur_devices->devices,
5729 devid, uuid);
5730 if (device)
5731 return device;
5732 }
5733 cur_devices = cur_devices->seed;
5734 }
5735 return NULL;
5736 }
5737
5738 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
5739 u64 devid, u8 *dev_uuid)
5740 {
5741 struct btrfs_device *device;
5742 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
5743
5744 device = btrfs_alloc_device(NULL, &devid, dev_uuid);
5745 if (IS_ERR(device))
5746 return NULL;
5747
5748 list_add(&device->dev_list, &fs_devices->devices);
5749 device->fs_devices = fs_devices;
5750 fs_devices->num_devices++;
5751
5752 device->missing = 1;
5753 fs_devices->missing_devices++;
5754
5755 return device;
5756 }
5757
5758 /**
5759 * btrfs_alloc_device - allocate struct btrfs_device
5760 * @fs_info: used only for generating a new devid, can be NULL if
5761 * devid is provided (i.e. @devid != NULL).
5762 * @devid: a pointer to devid for this device. If NULL a new devid
5763 * is generated.
5764 * @uuid: a pointer to UUID for this device. If NULL a new UUID
5765 * is generated.
5766 *
5767 * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR()
5768 * on error. Returned struct is not linked onto any lists and can be
5769 * destroyed with kfree() right away.
5770 */
5771 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
5772 const u64 *devid,
5773 const u8 *uuid)
5774 {
5775 struct btrfs_device *dev;
5776 u64 tmp;
5777
5778 if (WARN_ON(!devid && !fs_info))
5779 return ERR_PTR(-EINVAL);
5780
5781 dev = __alloc_device();
5782 if (IS_ERR(dev))
5783 return dev;
5784
5785 if (devid)
5786 tmp = *devid;
5787 else {
5788 int ret;
5789
5790 ret = find_next_devid(fs_info, &tmp);
5791 if (ret) {
5792 kfree(dev);
5793 return ERR_PTR(ret);
5794 }
5795 }
5796 dev->devid = tmp;
5797
5798 if (uuid)
5799 memcpy(dev->uuid, uuid, BTRFS_UUID_SIZE);
5800 else
5801 generate_random_uuid(dev->uuid);
5802
5803 btrfs_init_work(&dev->work, btrfs_submit_helper,
5804 pending_bios_fn, NULL, NULL);
5805
5806 return dev;
5807 }
5808
5809 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
5810 struct extent_buffer *leaf,
5811 struct btrfs_chunk *chunk)
5812 {
5813 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
5814 struct map_lookup *map;
5815 struct extent_map *em;
5816 u64 logical;
5817 u64 length;
5818 u64 devid;
5819 u8 uuid[BTRFS_UUID_SIZE];
5820 int num_stripes;
5821 int ret;
5822 int i;
5823
5824 logical = key->offset;
5825 length = btrfs_chunk_length(leaf, chunk);
5826
5827 read_lock(&map_tree->map_tree.lock);
5828 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
5829 read_unlock(&map_tree->map_tree.lock);
5830
5831 /* already mapped? */
5832 if (em && em->start <= logical && em->start + em->len > logical) {
5833 free_extent_map(em);
5834 return 0;
5835 } else if (em) {
5836 free_extent_map(em);
5837 }
5838
5839 em = alloc_extent_map();
5840 if (!em)
5841 return -ENOMEM;
5842 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
5843 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
5844 if (!map) {
5845 free_extent_map(em);
5846 return -ENOMEM;
5847 }
5848
5849 set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
5850 em->bdev = (struct block_device *)map;
5851 em->start = logical;
5852 em->len = length;
5853 em->orig_start = 0;
5854 em->block_start = 0;
5855 em->block_len = em->len;
5856
5857 map->num_stripes = num_stripes;
5858 map->io_width = btrfs_chunk_io_width(leaf, chunk);
5859 map->io_align = btrfs_chunk_io_align(leaf, chunk);
5860 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
5861 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
5862 map->type = btrfs_chunk_type(leaf, chunk);
5863 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
5864 for (i = 0; i < num_stripes; i++) {
5865 map->stripes[i].physical =
5866 btrfs_stripe_offset_nr(leaf, chunk, i);
5867 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
5868 read_extent_buffer(leaf, uuid, (unsigned long)
5869 btrfs_stripe_dev_uuid_nr(chunk, i),
5870 BTRFS_UUID_SIZE);
5871 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
5872 uuid, NULL);
5873 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
5874 free_extent_map(em);
5875 return -EIO;
5876 }
5877 if (!map->stripes[i].dev) {
5878 map->stripes[i].dev =
5879 add_missing_dev(root, devid, uuid);
5880 if (!map->stripes[i].dev) {
5881 free_extent_map(em);
5882 return -EIO;
5883 }
5884 }
5885 map->stripes[i].dev->in_fs_metadata = 1;
5886 }
5887
5888 write_lock(&map_tree->map_tree.lock);
5889 ret = add_extent_mapping(&map_tree->map_tree, em, 0);
5890 write_unlock(&map_tree->map_tree.lock);
5891 BUG_ON(ret); /* Tree corruption */
5892 free_extent_map(em);
5893
5894 return 0;
5895 }
5896
5897 static void fill_device_from_item(struct extent_buffer *leaf,
5898 struct btrfs_dev_item *dev_item,
5899 struct btrfs_device *device)
5900 {
5901 unsigned long ptr;
5902
5903 device->devid = btrfs_device_id(leaf, dev_item);
5904 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
5905 device->total_bytes = device->disk_total_bytes;
5906 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
5907 device->type = btrfs_device_type(leaf, dev_item);
5908 device->io_align = btrfs_device_io_align(leaf, dev_item);
5909 device->io_width = btrfs_device_io_width(leaf, dev_item);
5910 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
5911 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
5912 device->is_tgtdev_for_dev_replace = 0;
5913
5914 ptr = btrfs_device_uuid(dev_item);
5915 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
5916 }
5917
5918 static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
5919 {
5920 struct btrfs_fs_devices *fs_devices;
5921 int ret;
5922
5923 BUG_ON(!mutex_is_locked(&uuid_mutex));
5924
5925 fs_devices = root->fs_info->fs_devices->seed;
5926 while (fs_devices) {
5927 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
5928 ret = 0;
5929 goto out;
5930 }
5931 fs_devices = fs_devices->seed;
5932 }
5933
5934 fs_devices = find_fsid(fsid);
5935 if (!fs_devices) {
5936 ret = -ENOENT;
5937 goto out;
5938 }
5939
5940 fs_devices = clone_fs_devices(fs_devices);
5941 if (IS_ERR(fs_devices)) {
5942 ret = PTR_ERR(fs_devices);
5943 goto out;
5944 }
5945
5946 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
5947 root->fs_info->bdev_holder);
5948 if (ret) {
5949 free_fs_devices(fs_devices);
5950 goto out;
5951 }
5952
5953 if (!fs_devices->seeding) {
5954 __btrfs_close_devices(fs_devices);
5955 free_fs_devices(fs_devices);
5956 ret = -EINVAL;
5957 goto out;
5958 }
5959
5960 fs_devices->seed = root->fs_info->fs_devices->seed;
5961 root->fs_info->fs_devices->seed = fs_devices;
5962 out:
5963 return ret;
5964 }
5965
5966 static int read_one_dev(struct btrfs_root *root,
5967 struct extent_buffer *leaf,
5968 struct btrfs_dev_item *dev_item)
5969 {
5970 struct btrfs_device *device;
5971 u64 devid;
5972 int ret;
5973 u8 fs_uuid[BTRFS_UUID_SIZE];
5974 u8 dev_uuid[BTRFS_UUID_SIZE];
5975
5976 devid = btrfs_device_id(leaf, dev_item);
5977 read_extent_buffer(leaf, dev_uuid, btrfs_device_uuid(dev_item),
5978 BTRFS_UUID_SIZE);
5979 read_extent_buffer(leaf, fs_uuid, btrfs_device_fsid(dev_item),
5980 BTRFS_UUID_SIZE);
5981
5982 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
5983 ret = open_seed_devices(root, fs_uuid);
5984 if (ret && !btrfs_test_opt(root, DEGRADED))
5985 return ret;
5986 }
5987
5988 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
5989 if (!device || !device->bdev) {
5990 if (!btrfs_test_opt(root, DEGRADED))
5991 return -EIO;
5992
5993 if (!device) {
5994 btrfs_warn(root->fs_info, "devid %llu missing", devid);
5995 device = add_missing_dev(root, devid, dev_uuid);
5996 if (!device)
5997 return -ENOMEM;
5998 } else if (!device->missing) {
5999 /*
6000 * this happens when a device that was properly setup
6001 * in the device info lists suddenly goes bad.
6002 * device->bdev is NULL, and so we have to set
6003 * device->missing to one here
6004 */
6005 root->fs_info->fs_devices->missing_devices++;
6006 device->missing = 1;
6007 }
6008 }
6009
6010 if (device->fs_devices != root->fs_info->fs_devices) {
6011 BUG_ON(device->writeable);
6012 if (device->generation !=
6013 btrfs_device_generation(leaf, dev_item))
6014 return -EINVAL;
6015 }
6016
6017 fill_device_from_item(leaf, dev_item, device);
6018 device->in_fs_metadata = 1;
6019 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
6020 device->fs_devices->total_rw_bytes += device->total_bytes;
6021 spin_lock(&root->fs_info->free_chunk_lock);
6022 root->fs_info->free_chunk_space += device->total_bytes -
6023 device->bytes_used;
6024 spin_unlock(&root->fs_info->free_chunk_lock);
6025 }
6026 ret = 0;
6027 return ret;
6028 }
6029
6030 int btrfs_read_sys_array(struct btrfs_root *root)
6031 {
6032 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
6033 struct extent_buffer *sb;
6034 struct btrfs_disk_key *disk_key;
6035 struct btrfs_chunk *chunk;
6036 u8 *ptr;
6037 unsigned long sb_ptr;
6038 int ret = 0;
6039 u32 num_stripes;
6040 u32 array_size;
6041 u32 len = 0;
6042 u32 cur;
6043 struct btrfs_key key;
6044
6045 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
6046 BTRFS_SUPER_INFO_SIZE);
6047 if (!sb)
6048 return -ENOMEM;
6049 btrfs_set_buffer_uptodate(sb);
6050 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
6051 /*
6052 * The sb extent buffer is artifical and just used to read the system array.
6053 * btrfs_set_buffer_uptodate() call does not properly mark all it's
6054 * pages up-to-date when the page is larger: extent does not cover the
6055 * whole page and consequently check_page_uptodate does not find all
6056 * the page's extents up-to-date (the hole beyond sb),
6057 * write_extent_buffer then triggers a WARN_ON.
6058 *
6059 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
6060 * but sb spans only this function. Add an explicit SetPageUptodate call
6061 * to silence the warning eg. on PowerPC 64.
6062 */
6063 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
6064 SetPageUptodate(sb->pages[0]);
6065
6066 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
6067 array_size = btrfs_super_sys_array_size(super_copy);
6068
6069 ptr = super_copy->sys_chunk_array;
6070 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
6071 cur = 0;
6072
6073 while (cur < array_size) {
6074 disk_key = (struct btrfs_disk_key *)ptr;
6075 btrfs_disk_key_to_cpu(&key, disk_key);
6076
6077 len = sizeof(*disk_key); ptr += len;
6078 sb_ptr += len;
6079 cur += len;
6080
6081 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
6082 chunk = (struct btrfs_chunk *)sb_ptr;
6083 ret = read_one_chunk(root, &key, sb, chunk);
6084 if (ret)
6085 break;
6086 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
6087 len = btrfs_chunk_item_size(num_stripes);
6088 } else {
6089 ret = -EIO;
6090 break;
6091 }
6092 ptr += len;
6093 sb_ptr += len;
6094 cur += len;
6095 }
6096 free_extent_buffer(sb);
6097 return ret;
6098 }
6099
6100 int btrfs_read_chunk_tree(struct btrfs_root *root)
6101 {
6102 struct btrfs_path *path;
6103 struct extent_buffer *leaf;
6104 struct btrfs_key key;
6105 struct btrfs_key found_key;
6106 int ret;
6107 int slot;
6108
6109 root = root->fs_info->chunk_root;
6110
6111 path = btrfs_alloc_path();
6112 if (!path)
6113 return -ENOMEM;
6114
6115 mutex_lock(&uuid_mutex);
6116 lock_chunks(root);
6117
6118 /*
6119 * Read all device items, and then all the chunk items. All
6120 * device items are found before any chunk item (their object id
6121 * is smaller than the lowest possible object id for a chunk
6122 * item - BTRFS_FIRST_CHUNK_TREE_OBJECTID).
6123 */
6124 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
6125 key.offset = 0;
6126 key.type = 0;
6127 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
6128 if (ret < 0)
6129 goto error;
6130 while (1) {
6131 leaf = path->nodes[0];
6132 slot = path->slots[0];
6133 if (slot >= btrfs_header_nritems(leaf)) {
6134 ret = btrfs_next_leaf(root, path);
6135 if (ret == 0)
6136 continue;
6137 if (ret < 0)
6138 goto error;
6139 break;
6140 }
6141 btrfs_item_key_to_cpu(leaf, &found_key, slot);
6142 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
6143 struct btrfs_dev_item *dev_item;
6144 dev_item = btrfs_item_ptr(leaf, slot,
6145 struct btrfs_dev_item);
6146 ret = read_one_dev(root, leaf, dev_item);
6147 if (ret)
6148 goto error;
6149 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
6150 struct btrfs_chunk *chunk;
6151 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
6152 ret = read_one_chunk(root, &found_key, leaf, chunk);
6153 if (ret)
6154 goto error;
6155 }
6156 path->slots[0]++;
6157 }
6158 ret = 0;
6159 error:
6160 unlock_chunks(root);
6161 mutex_unlock(&uuid_mutex);
6162
6163 btrfs_free_path(path);
6164 return ret;
6165 }
6166
6167 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info)
6168 {
6169 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6170 struct btrfs_device *device;
6171
6172 while (fs_devices) {
6173 mutex_lock(&fs_devices->device_list_mutex);
6174 list_for_each_entry(device, &fs_devices->devices, dev_list)
6175 device->dev_root = fs_info->dev_root;
6176 mutex_unlock(&fs_devices->device_list_mutex);
6177
6178 fs_devices = fs_devices->seed;
6179 }
6180 }
6181
6182 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
6183 {
6184 int i;
6185
6186 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6187 btrfs_dev_stat_reset(dev, i);
6188 }
6189
6190 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
6191 {
6192 struct btrfs_key key;
6193 struct btrfs_key found_key;
6194 struct btrfs_root *dev_root = fs_info->dev_root;
6195 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6196 struct extent_buffer *eb;
6197 int slot;
6198 int ret = 0;
6199 struct btrfs_device *device;
6200 struct btrfs_path *path = NULL;
6201 int i;
6202
6203 path = btrfs_alloc_path();
6204 if (!path) {
6205 ret = -ENOMEM;
6206 goto out;
6207 }
6208
6209 mutex_lock(&fs_devices->device_list_mutex);
6210 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6211 int item_size;
6212 struct btrfs_dev_stats_item *ptr;
6213
6214 key.objectid = 0;
6215 key.type = BTRFS_DEV_STATS_KEY;
6216 key.offset = device->devid;
6217 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
6218 if (ret) {
6219 __btrfs_reset_dev_stats(device);
6220 device->dev_stats_valid = 1;
6221 btrfs_release_path(path);
6222 continue;
6223 }
6224 slot = path->slots[0];
6225 eb = path->nodes[0];
6226 btrfs_item_key_to_cpu(eb, &found_key, slot);
6227 item_size = btrfs_item_size_nr(eb, slot);
6228
6229 ptr = btrfs_item_ptr(eb, slot,
6230 struct btrfs_dev_stats_item);
6231
6232 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6233 if (item_size >= (1 + i) * sizeof(__le64))
6234 btrfs_dev_stat_set(device, i,
6235 btrfs_dev_stats_value(eb, ptr, i));
6236 else
6237 btrfs_dev_stat_reset(device, i);
6238 }
6239
6240 device->dev_stats_valid = 1;
6241 btrfs_dev_stat_print_on_load(device);
6242 btrfs_release_path(path);
6243 }
6244 mutex_unlock(&fs_devices->device_list_mutex);
6245
6246 out:
6247 btrfs_free_path(path);
6248 return ret < 0 ? ret : 0;
6249 }
6250
6251 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
6252 struct btrfs_root *dev_root,
6253 struct btrfs_device *device)
6254 {
6255 struct btrfs_path *path;
6256 struct btrfs_key key;
6257 struct extent_buffer *eb;
6258 struct btrfs_dev_stats_item *ptr;
6259 int ret;
6260 int i;
6261
6262 key.objectid = 0;
6263 key.type = BTRFS_DEV_STATS_KEY;
6264 key.offset = device->devid;
6265
6266 path = btrfs_alloc_path();
6267 BUG_ON(!path);
6268 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
6269 if (ret < 0) {
6270 printk_in_rcu(KERN_WARNING "BTRFS: "
6271 "error %d while searching for dev_stats item for device %s!\n",
6272 ret, rcu_str_deref(device->name));
6273 goto out;
6274 }
6275
6276 if (ret == 0 &&
6277 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
6278 /* need to delete old one and insert a new one */
6279 ret = btrfs_del_item(trans, dev_root, path);
6280 if (ret != 0) {
6281 printk_in_rcu(KERN_WARNING "BTRFS: "
6282 "delete too small dev_stats item for device %s failed %d!\n",
6283 rcu_str_deref(device->name), ret);
6284 goto out;
6285 }
6286 ret = 1;
6287 }
6288
6289 if (ret == 1) {
6290 /* need to insert a new item */
6291 btrfs_release_path(path);
6292 ret = btrfs_insert_empty_item(trans, dev_root, path,
6293 &key, sizeof(*ptr));
6294 if (ret < 0) {
6295 printk_in_rcu(KERN_WARNING "BTRFS: "
6296 "insert dev_stats item for device %s failed %d!\n",
6297 rcu_str_deref(device->name), ret);
6298 goto out;
6299 }
6300 }
6301
6302 eb = path->nodes[0];
6303 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
6304 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6305 btrfs_set_dev_stats_value(eb, ptr, i,
6306 btrfs_dev_stat_read(device, i));
6307 btrfs_mark_buffer_dirty(eb);
6308
6309 out:
6310 btrfs_free_path(path);
6311 return ret;
6312 }
6313
6314 /*
6315 * called from commit_transaction. Writes all changed device stats to disk.
6316 */
6317 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
6318 struct btrfs_fs_info *fs_info)
6319 {
6320 struct btrfs_root *dev_root = fs_info->dev_root;
6321 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
6322 struct btrfs_device *device;
6323 int ret = 0;
6324
6325 mutex_lock(&fs_devices->device_list_mutex);
6326 list_for_each_entry(device, &fs_devices->devices, dev_list) {
6327 if (!device->dev_stats_valid || !device->dev_stats_dirty)
6328 continue;
6329
6330 ret = update_dev_stat_item(trans, dev_root, device);
6331 if (!ret)
6332 device->dev_stats_dirty = 0;
6333 }
6334 mutex_unlock(&fs_devices->device_list_mutex);
6335
6336 return ret;
6337 }
6338
6339 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
6340 {
6341 btrfs_dev_stat_inc(dev, index);
6342 btrfs_dev_stat_print_on_error(dev);
6343 }
6344
6345 static void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
6346 {
6347 if (!dev->dev_stats_valid)
6348 return;
6349 printk_ratelimited_in_rcu(KERN_ERR "BTRFS: "
6350 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6351 rcu_str_deref(dev->name),
6352 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6353 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6354 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6355 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6356 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6357 }
6358
6359 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
6360 {
6361 int i;
6362
6363 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6364 if (btrfs_dev_stat_read(dev, i) != 0)
6365 break;
6366 if (i == BTRFS_DEV_STAT_VALUES_MAX)
6367 return; /* all values == 0, suppress message */
6368
6369 printk_in_rcu(KERN_INFO "BTRFS: "
6370 "bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
6371 rcu_str_deref(dev->name),
6372 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
6373 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
6374 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
6375 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
6376 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
6377 }
6378
6379 int btrfs_get_dev_stats(struct btrfs_root *root,
6380 struct btrfs_ioctl_get_dev_stats *stats)
6381 {
6382 struct btrfs_device *dev;
6383 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
6384 int i;
6385
6386 mutex_lock(&fs_devices->device_list_mutex);
6387 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
6388 mutex_unlock(&fs_devices->device_list_mutex);
6389
6390 if (!dev) {
6391 btrfs_warn(root->fs_info, "get dev_stats failed, device not found");
6392 return -ENODEV;
6393 } else if (!dev->dev_stats_valid) {
6394 btrfs_warn(root->fs_info, "get dev_stats failed, not yet valid");
6395 return -ENODEV;
6396 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
6397 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
6398 if (stats->nr_items > i)
6399 stats->values[i] =
6400 btrfs_dev_stat_read_and_reset(dev, i);
6401 else
6402 btrfs_dev_stat_reset(dev, i);
6403 }
6404 } else {
6405 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
6406 if (stats->nr_items > i)
6407 stats->values[i] = btrfs_dev_stat_read(dev, i);
6408 }
6409 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
6410 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
6411 return 0;
6412 }
6413
6414 int btrfs_scratch_superblock(struct btrfs_device *device)
6415 {
6416 struct buffer_head *bh;
6417 struct btrfs_super_block *disk_super;
6418
6419 bh = btrfs_read_dev_super(device->bdev);
6420 if (!bh)
6421 return -EINVAL;
6422 disk_super = (struct btrfs_super_block *)bh->b_data;
6423
6424 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
6425 set_buffer_dirty(bh);
6426 sync_dirty_buffer(bh);
6427 brelse(bh);
6428
6429 return 0;
6430 }
Linux with added FPC-III support