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Btrfs: RAID5 and RAID6
[deliverable/linux.git] / fs / btrfs / volumes.c
1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18 #include <linux/sched.h>
19 #include <linux/bio.h>
20 #include <linux/slab.h>
21 #include <linux/buffer_head.h>
22 #include <linux/blkdev.h>
23 #include <linux/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 <asm/div64.h>
30 #include "compat.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
44 static int init_first_rw_device(struct btrfs_trans_handle *trans,
45 struct btrfs_root *root,
46 struct btrfs_device *device);
47 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
48 static void __btrfs_reset_dev_stats(struct btrfs_device *dev);
49 static void btrfs_dev_stat_print_on_load(struct btrfs_device *device);
50
51 static DEFINE_MUTEX(uuid_mutex);
52 static LIST_HEAD(fs_uuids);
53
54 static void lock_chunks(struct btrfs_root *root)
55 {
56 mutex_lock(&root->fs_info->chunk_mutex);
57 }
58
59 static void unlock_chunks(struct btrfs_root *root)
60 {
61 mutex_unlock(&root->fs_info->chunk_mutex);
62 }
63
64 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
65 {
66 struct btrfs_device *device;
67 WARN_ON(fs_devices->opened);
68 while (!list_empty(&fs_devices->devices)) {
69 device = list_entry(fs_devices->devices.next,
70 struct btrfs_device, dev_list);
71 list_del(&device->dev_list);
72 rcu_string_free(device->name);
73 kfree(device);
74 }
75 kfree(fs_devices);
76 }
77
78 static void btrfs_kobject_uevent(struct block_device *bdev,
79 enum kobject_action action)
80 {
81 int ret;
82
83 ret = kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, action);
84 if (ret)
85 pr_warn("Sending event '%d' to kobject: '%s' (%p): failed\n",
86 action,
87 kobject_name(&disk_to_dev(bdev->bd_disk)->kobj),
88 &disk_to_dev(bdev->bd_disk)->kobj);
89 }
90
91 void btrfs_cleanup_fs_uuids(void)
92 {
93 struct btrfs_fs_devices *fs_devices;
94
95 while (!list_empty(&fs_uuids)) {
96 fs_devices = list_entry(fs_uuids.next,
97 struct btrfs_fs_devices, list);
98 list_del(&fs_devices->list);
99 free_fs_devices(fs_devices);
100 }
101 }
102
103 static noinline struct btrfs_device *__find_device(struct list_head *head,
104 u64 devid, u8 *uuid)
105 {
106 struct btrfs_device *dev;
107
108 list_for_each_entry(dev, head, dev_list) {
109 if (dev->devid == devid &&
110 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
111 return dev;
112 }
113 }
114 return NULL;
115 }
116
117 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
118 {
119 struct btrfs_fs_devices *fs_devices;
120
121 list_for_each_entry(fs_devices, &fs_uuids, list) {
122 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
123 return fs_devices;
124 }
125 return NULL;
126 }
127
128 static int
129 btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
130 int flush, struct block_device **bdev,
131 struct buffer_head **bh)
132 {
133 int ret;
134
135 *bdev = blkdev_get_by_path(device_path, flags, holder);
136
137 if (IS_ERR(*bdev)) {
138 ret = PTR_ERR(*bdev);
139 printk(KERN_INFO "btrfs: open %s failed\n", device_path);
140 goto error;
141 }
142
143 if (flush)
144 filemap_write_and_wait((*bdev)->bd_inode->i_mapping);
145 ret = set_blocksize(*bdev, 4096);
146 if (ret) {
147 blkdev_put(*bdev, flags);
148 goto error;
149 }
150 invalidate_bdev(*bdev);
151 *bh = btrfs_read_dev_super(*bdev);
152 if (!*bh) {
153 ret = -EINVAL;
154 blkdev_put(*bdev, flags);
155 goto error;
156 }
157
158 return 0;
159
160 error:
161 *bdev = NULL;
162 *bh = NULL;
163 return ret;
164 }
165
166 static void requeue_list(struct btrfs_pending_bios *pending_bios,
167 struct bio *head, struct bio *tail)
168 {
169
170 struct bio *old_head;
171
172 old_head = pending_bios->head;
173 pending_bios->head = head;
174 if (pending_bios->tail)
175 tail->bi_next = old_head;
176 else
177 pending_bios->tail = tail;
178 }
179
180 /*
181 * we try to collect pending bios for a device so we don't get a large
182 * number of procs sending bios down to the same device. This greatly
183 * improves the schedulers ability to collect and merge the bios.
184 *
185 * But, it also turns into a long list of bios to process and that is sure
186 * to eventually make the worker thread block. The solution here is to
187 * make some progress and then put this work struct back at the end of
188 * the list if the block device is congested. This way, multiple devices
189 * can make progress from a single worker thread.
190 */
191 static noinline void run_scheduled_bios(struct btrfs_device *device)
192 {
193 struct bio *pending;
194 struct backing_dev_info *bdi;
195 struct btrfs_fs_info *fs_info;
196 struct btrfs_pending_bios *pending_bios;
197 struct bio *tail;
198 struct bio *cur;
199 int again = 0;
200 unsigned long num_run;
201 unsigned long batch_run = 0;
202 unsigned long limit;
203 unsigned long last_waited = 0;
204 int force_reg = 0;
205 int sync_pending = 0;
206 struct blk_plug plug;
207
208 /*
209 * this function runs all the bios we've collected for
210 * a particular device. We don't want to wander off to
211 * another device without first sending all of these down.
212 * So, setup a plug here and finish it off before we return
213 */
214 blk_start_plug(&plug);
215
216 bdi = blk_get_backing_dev_info(device->bdev);
217 fs_info = device->dev_root->fs_info;
218 limit = btrfs_async_submit_limit(fs_info);
219 limit = limit * 2 / 3;
220
221 loop:
222 spin_lock(&device->io_lock);
223
224 loop_lock:
225 num_run = 0;
226
227 /* take all the bios off the list at once and process them
228 * later on (without the lock held). But, remember the
229 * tail and other pointers so the bios can be properly reinserted
230 * into the list if we hit congestion
231 */
232 if (!force_reg && device->pending_sync_bios.head) {
233 pending_bios = &device->pending_sync_bios;
234 force_reg = 1;
235 } else {
236 pending_bios = &device->pending_bios;
237 force_reg = 0;
238 }
239
240 pending = pending_bios->head;
241 tail = pending_bios->tail;
242 WARN_ON(pending && !tail);
243
244 /*
245 * if pending was null this time around, no bios need processing
246 * at all and we can stop. Otherwise it'll loop back up again
247 * and do an additional check so no bios are missed.
248 *
249 * device->running_pending is used to synchronize with the
250 * schedule_bio code.
251 */
252 if (device->pending_sync_bios.head == NULL &&
253 device->pending_bios.head == NULL) {
254 again = 0;
255 device->running_pending = 0;
256 } else {
257 again = 1;
258 device->running_pending = 1;
259 }
260
261 pending_bios->head = NULL;
262 pending_bios->tail = NULL;
263
264 spin_unlock(&device->io_lock);
265
266 while (pending) {
267
268 rmb();
269 /* we want to work on both lists, but do more bios on the
270 * sync list than the regular list
271 */
272 if ((num_run > 32 &&
273 pending_bios != &device->pending_sync_bios &&
274 device->pending_sync_bios.head) ||
275 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
276 device->pending_bios.head)) {
277 spin_lock(&device->io_lock);
278 requeue_list(pending_bios, pending, tail);
279 goto loop_lock;
280 }
281
282 cur = pending;
283 pending = pending->bi_next;
284 cur->bi_next = NULL;
285
286 if (atomic_dec_return(&fs_info->nr_async_bios) < limit &&
287 waitqueue_active(&fs_info->async_submit_wait))
288 wake_up(&fs_info->async_submit_wait);
289
290 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
291
292 /*
293 * if we're doing the sync list, record that our
294 * plug has some sync requests on it
295 *
296 * If we're doing the regular list and there are
297 * sync requests sitting around, unplug before
298 * we add more
299 */
300 if (pending_bios == &device->pending_sync_bios) {
301 sync_pending = 1;
302 } else if (sync_pending) {
303 blk_finish_plug(&plug);
304 blk_start_plug(&plug);
305 sync_pending = 0;
306 }
307
308 btrfsic_submit_bio(cur->bi_rw, cur);
309 num_run++;
310 batch_run++;
311 if (need_resched())
312 cond_resched();
313
314 /*
315 * we made progress, there is more work to do and the bdi
316 * is now congested. Back off and let other work structs
317 * run instead
318 */
319 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
320 fs_info->fs_devices->open_devices > 1) {
321 struct io_context *ioc;
322
323 ioc = current->io_context;
324
325 /*
326 * the main goal here is that we don't want to
327 * block if we're going to be able to submit
328 * more requests without blocking.
329 *
330 * This code does two great things, it pokes into
331 * the elevator code from a filesystem _and_
332 * it makes assumptions about how batching works.
333 */
334 if (ioc && ioc->nr_batch_requests > 0 &&
335 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
336 (last_waited == 0 ||
337 ioc->last_waited == last_waited)) {
338 /*
339 * we want to go through our batch of
340 * requests and stop. So, we copy out
341 * the ioc->last_waited time and test
342 * against it before looping
343 */
344 last_waited = ioc->last_waited;
345 if (need_resched())
346 cond_resched();
347 continue;
348 }
349 spin_lock(&device->io_lock);
350 requeue_list(pending_bios, pending, tail);
351 device->running_pending = 1;
352
353 spin_unlock(&device->io_lock);
354 btrfs_requeue_work(&device->work);
355 goto done;
356 }
357 /* unplug every 64 requests just for good measure */
358 if (batch_run % 64 == 0) {
359 blk_finish_plug(&plug);
360 blk_start_plug(&plug);
361 sync_pending = 0;
362 }
363 }
364
365 cond_resched();
366 if (again)
367 goto loop;
368
369 spin_lock(&device->io_lock);
370 if (device->pending_bios.head || device->pending_sync_bios.head)
371 goto loop_lock;
372 spin_unlock(&device->io_lock);
373
374 done:
375 blk_finish_plug(&plug);
376 }
377
378 static void pending_bios_fn(struct btrfs_work *work)
379 {
380 struct btrfs_device *device;
381
382 device = container_of(work, struct btrfs_device, work);
383 run_scheduled_bios(device);
384 }
385
386 static noinline int device_list_add(const char *path,
387 struct btrfs_super_block *disk_super,
388 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
389 {
390 struct btrfs_device *device;
391 struct btrfs_fs_devices *fs_devices;
392 struct rcu_string *name;
393 u64 found_transid = btrfs_super_generation(disk_super);
394
395 fs_devices = find_fsid(disk_super->fsid);
396 if (!fs_devices) {
397 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
398 if (!fs_devices)
399 return -ENOMEM;
400 INIT_LIST_HEAD(&fs_devices->devices);
401 INIT_LIST_HEAD(&fs_devices->alloc_list);
402 list_add(&fs_devices->list, &fs_uuids);
403 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
404 fs_devices->latest_devid = devid;
405 fs_devices->latest_trans = found_transid;
406 mutex_init(&fs_devices->device_list_mutex);
407 device = NULL;
408 } else {
409 device = __find_device(&fs_devices->devices, devid,
410 disk_super->dev_item.uuid);
411 }
412 if (!device) {
413 if (fs_devices->opened)
414 return -EBUSY;
415
416 device = kzalloc(sizeof(*device), GFP_NOFS);
417 if (!device) {
418 /* we can safely leave the fs_devices entry around */
419 return -ENOMEM;
420 }
421 device->devid = devid;
422 device->dev_stats_valid = 0;
423 device->work.func = pending_bios_fn;
424 memcpy(device->uuid, disk_super->dev_item.uuid,
425 BTRFS_UUID_SIZE);
426 spin_lock_init(&device->io_lock);
427
428 name = rcu_string_strdup(path, GFP_NOFS);
429 if (!name) {
430 kfree(device);
431 return -ENOMEM;
432 }
433 rcu_assign_pointer(device->name, name);
434 INIT_LIST_HEAD(&device->dev_alloc_list);
435
436 /* init readahead state */
437 spin_lock_init(&device->reada_lock);
438 device->reada_curr_zone = NULL;
439 atomic_set(&device->reada_in_flight, 0);
440 device->reada_next = 0;
441 INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT);
442 INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT);
443
444 mutex_lock(&fs_devices->device_list_mutex);
445 list_add_rcu(&device->dev_list, &fs_devices->devices);
446 mutex_unlock(&fs_devices->device_list_mutex);
447
448 device->fs_devices = fs_devices;
449 fs_devices->num_devices++;
450 } else if (!device->name || strcmp(device->name->str, path)) {
451 name = rcu_string_strdup(path, GFP_NOFS);
452 if (!name)
453 return -ENOMEM;
454 rcu_string_free(device->name);
455 rcu_assign_pointer(device->name, name);
456 if (device->missing) {
457 fs_devices->missing_devices--;
458 device->missing = 0;
459 }
460 }
461
462 if (found_transid > fs_devices->latest_trans) {
463 fs_devices->latest_devid = devid;
464 fs_devices->latest_trans = found_transid;
465 }
466 *fs_devices_ret = fs_devices;
467 return 0;
468 }
469
470 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
471 {
472 struct btrfs_fs_devices *fs_devices;
473 struct btrfs_device *device;
474 struct btrfs_device *orig_dev;
475
476 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
477 if (!fs_devices)
478 return ERR_PTR(-ENOMEM);
479
480 INIT_LIST_HEAD(&fs_devices->devices);
481 INIT_LIST_HEAD(&fs_devices->alloc_list);
482 INIT_LIST_HEAD(&fs_devices->list);
483 mutex_init(&fs_devices->device_list_mutex);
484 fs_devices->latest_devid = orig->latest_devid;
485 fs_devices->latest_trans = orig->latest_trans;
486 fs_devices->total_devices = orig->total_devices;
487 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid));
488
489 /* We have held the volume lock, it is safe to get the devices. */
490 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
491 struct rcu_string *name;
492
493 device = kzalloc(sizeof(*device), GFP_NOFS);
494 if (!device)
495 goto error;
496
497 /*
498 * This is ok to do without rcu read locked because we hold the
499 * uuid mutex so nothing we touch in here is going to disappear.
500 */
501 name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
502 if (!name) {
503 kfree(device);
504 goto error;
505 }
506 rcu_assign_pointer(device->name, name);
507
508 device->devid = orig_dev->devid;
509 device->work.func = pending_bios_fn;
510 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid));
511 spin_lock_init(&device->io_lock);
512 INIT_LIST_HEAD(&device->dev_list);
513 INIT_LIST_HEAD(&device->dev_alloc_list);
514
515 list_add(&device->dev_list, &fs_devices->devices);
516 device->fs_devices = fs_devices;
517 fs_devices->num_devices++;
518 }
519 return fs_devices;
520 error:
521 free_fs_devices(fs_devices);
522 return ERR_PTR(-ENOMEM);
523 }
524
525 void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info,
526 struct btrfs_fs_devices *fs_devices, int step)
527 {
528 struct btrfs_device *device, *next;
529
530 struct block_device *latest_bdev = NULL;
531 u64 latest_devid = 0;
532 u64 latest_transid = 0;
533
534 mutex_lock(&uuid_mutex);
535 again:
536 /* This is the initialized path, it is safe to release the devices. */
537 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
538 if (device->in_fs_metadata) {
539 if (!device->is_tgtdev_for_dev_replace &&
540 (!latest_transid ||
541 device->generation > latest_transid)) {
542 latest_devid = device->devid;
543 latest_transid = device->generation;
544 latest_bdev = device->bdev;
545 }
546 continue;
547 }
548
549 if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
550 /*
551 * In the first step, keep the device which has
552 * the correct fsid and the devid that is used
553 * for the dev_replace procedure.
554 * In the second step, the dev_replace state is
555 * read from the device tree and it is known
556 * whether the procedure is really active or
557 * not, which means whether this device is
558 * used or whether it should be removed.
559 */
560 if (step == 0 || device->is_tgtdev_for_dev_replace) {
561 continue;
562 }
563 }
564 if (device->bdev) {
565 blkdev_put(device->bdev, device->mode);
566 device->bdev = NULL;
567 fs_devices->open_devices--;
568 }
569 if (device->writeable) {
570 list_del_init(&device->dev_alloc_list);
571 device->writeable = 0;
572 if (!device->is_tgtdev_for_dev_replace)
573 fs_devices->rw_devices--;
574 }
575 list_del_init(&device->dev_list);
576 fs_devices->num_devices--;
577 rcu_string_free(device->name);
578 kfree(device);
579 }
580
581 if (fs_devices->seed) {
582 fs_devices = fs_devices->seed;
583 goto again;
584 }
585
586 fs_devices->latest_bdev = latest_bdev;
587 fs_devices->latest_devid = latest_devid;
588 fs_devices->latest_trans = latest_transid;
589
590 mutex_unlock(&uuid_mutex);
591 }
592
593 static void __free_device(struct work_struct *work)
594 {
595 struct btrfs_device *device;
596
597 device = container_of(work, struct btrfs_device, rcu_work);
598
599 if (device->bdev)
600 blkdev_put(device->bdev, device->mode);
601
602 rcu_string_free(device->name);
603 kfree(device);
604 }
605
606 static void free_device(struct rcu_head *head)
607 {
608 struct btrfs_device *device;
609
610 device = container_of(head, struct btrfs_device, rcu);
611
612 INIT_WORK(&device->rcu_work, __free_device);
613 schedule_work(&device->rcu_work);
614 }
615
616 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
617 {
618 struct btrfs_device *device;
619
620 if (--fs_devices->opened > 0)
621 return 0;
622
623 mutex_lock(&fs_devices->device_list_mutex);
624 list_for_each_entry(device, &fs_devices->devices, dev_list) {
625 struct btrfs_device *new_device;
626 struct rcu_string *name;
627
628 if (device->bdev)
629 fs_devices->open_devices--;
630
631 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
632 list_del_init(&device->dev_alloc_list);
633 fs_devices->rw_devices--;
634 }
635
636 if (device->can_discard)
637 fs_devices->num_can_discard--;
638
639 new_device = kmalloc(sizeof(*new_device), GFP_NOFS);
640 BUG_ON(!new_device); /* -ENOMEM */
641 memcpy(new_device, device, sizeof(*new_device));
642
643 /* Safe because we are under uuid_mutex */
644 if (device->name) {
645 name = rcu_string_strdup(device->name->str, GFP_NOFS);
646 BUG_ON(device->name && !name); /* -ENOMEM */
647 rcu_assign_pointer(new_device->name, name);
648 }
649 new_device->bdev = NULL;
650 new_device->writeable = 0;
651 new_device->in_fs_metadata = 0;
652 new_device->can_discard = 0;
653 list_replace_rcu(&device->dev_list, &new_device->dev_list);
654
655 call_rcu(&device->rcu, free_device);
656 }
657 mutex_unlock(&fs_devices->device_list_mutex);
658
659 WARN_ON(fs_devices->open_devices);
660 WARN_ON(fs_devices->rw_devices);
661 fs_devices->opened = 0;
662 fs_devices->seeding = 0;
663
664 return 0;
665 }
666
667 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
668 {
669 struct btrfs_fs_devices *seed_devices = NULL;
670 int ret;
671
672 mutex_lock(&uuid_mutex);
673 ret = __btrfs_close_devices(fs_devices);
674 if (!fs_devices->opened) {
675 seed_devices = fs_devices->seed;
676 fs_devices->seed = NULL;
677 }
678 mutex_unlock(&uuid_mutex);
679
680 while (seed_devices) {
681 fs_devices = seed_devices;
682 seed_devices = fs_devices->seed;
683 __btrfs_close_devices(fs_devices);
684 free_fs_devices(fs_devices);
685 }
686 return ret;
687 }
688
689 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
690 fmode_t flags, void *holder)
691 {
692 struct request_queue *q;
693 struct block_device *bdev;
694 struct list_head *head = &fs_devices->devices;
695 struct btrfs_device *device;
696 struct block_device *latest_bdev = NULL;
697 struct buffer_head *bh;
698 struct btrfs_super_block *disk_super;
699 u64 latest_devid = 0;
700 u64 latest_transid = 0;
701 u64 devid;
702 int seeding = 1;
703 int ret = 0;
704
705 flags |= FMODE_EXCL;
706
707 list_for_each_entry(device, head, dev_list) {
708 if (device->bdev)
709 continue;
710 if (!device->name)
711 continue;
712
713 ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
714 &bdev, &bh);
715 if (ret)
716 continue;
717
718 disk_super = (struct btrfs_super_block *)bh->b_data;
719 devid = btrfs_stack_device_id(&disk_super->dev_item);
720 if (devid != device->devid)
721 goto error_brelse;
722
723 if (memcmp(device->uuid, disk_super->dev_item.uuid,
724 BTRFS_UUID_SIZE))
725 goto error_brelse;
726
727 device->generation = btrfs_super_generation(disk_super);
728 if (!latest_transid || device->generation > latest_transid) {
729 latest_devid = devid;
730 latest_transid = device->generation;
731 latest_bdev = bdev;
732 }
733
734 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
735 device->writeable = 0;
736 } else {
737 device->writeable = !bdev_read_only(bdev);
738 seeding = 0;
739 }
740
741 q = bdev_get_queue(bdev);
742 if (blk_queue_discard(q)) {
743 device->can_discard = 1;
744 fs_devices->num_can_discard++;
745 }
746
747 device->bdev = bdev;
748 device->in_fs_metadata = 0;
749 device->mode = flags;
750
751 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
752 fs_devices->rotating = 1;
753
754 fs_devices->open_devices++;
755 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
756 fs_devices->rw_devices++;
757 list_add(&device->dev_alloc_list,
758 &fs_devices->alloc_list);
759 }
760 brelse(bh);
761 continue;
762
763 error_brelse:
764 brelse(bh);
765 blkdev_put(bdev, flags);
766 continue;
767 }
768 if (fs_devices->open_devices == 0) {
769 ret = -EINVAL;
770 goto out;
771 }
772 fs_devices->seeding = seeding;
773 fs_devices->opened = 1;
774 fs_devices->latest_bdev = latest_bdev;
775 fs_devices->latest_devid = latest_devid;
776 fs_devices->latest_trans = latest_transid;
777 fs_devices->total_rw_bytes = 0;
778 out:
779 return ret;
780 }
781
782 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
783 fmode_t flags, void *holder)
784 {
785 int ret;
786
787 mutex_lock(&uuid_mutex);
788 if (fs_devices->opened) {
789 fs_devices->opened++;
790 ret = 0;
791 } else {
792 ret = __btrfs_open_devices(fs_devices, flags, holder);
793 }
794 mutex_unlock(&uuid_mutex);
795 return ret;
796 }
797
798 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
799 struct btrfs_fs_devices **fs_devices_ret)
800 {
801 struct btrfs_super_block *disk_super;
802 struct block_device *bdev;
803 struct buffer_head *bh;
804 int ret;
805 u64 devid;
806 u64 transid;
807 u64 total_devices;
808
809 flags |= FMODE_EXCL;
810 mutex_lock(&uuid_mutex);
811 ret = btrfs_get_bdev_and_sb(path, flags, holder, 0, &bdev, &bh);
812 if (ret)
813 goto error;
814 disk_super = (struct btrfs_super_block *)bh->b_data;
815 devid = btrfs_stack_device_id(&disk_super->dev_item);
816 transid = btrfs_super_generation(disk_super);
817 total_devices = btrfs_super_num_devices(disk_super);
818 if (disk_super->label[0]) {
819 if (disk_super->label[BTRFS_LABEL_SIZE - 1])
820 disk_super->label[BTRFS_LABEL_SIZE - 1] = '\0';
821 printk(KERN_INFO "device label %s ", disk_super->label);
822 } else {
823 printk(KERN_INFO "device fsid %pU ", disk_super->fsid);
824 }
825 printk(KERN_CONT "devid %llu transid %llu %s\n",
826 (unsigned long long)devid, (unsigned long long)transid, path);
827 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
828 if (!ret && fs_devices_ret)
829 (*fs_devices_ret)->total_devices = total_devices;
830 brelse(bh);
831 blkdev_put(bdev, flags);
832 error:
833 mutex_unlock(&uuid_mutex);
834 return ret;
835 }
836
837 /* helper to account the used device space in the range */
838 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
839 u64 end, u64 *length)
840 {
841 struct btrfs_key key;
842 struct btrfs_root *root = device->dev_root;
843 struct btrfs_dev_extent *dev_extent;
844 struct btrfs_path *path;
845 u64 extent_end;
846 int ret;
847 int slot;
848 struct extent_buffer *l;
849
850 *length = 0;
851
852 if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
853 return 0;
854
855 path = btrfs_alloc_path();
856 if (!path)
857 return -ENOMEM;
858 path->reada = 2;
859
860 key.objectid = device->devid;
861 key.offset = start;
862 key.type = BTRFS_DEV_EXTENT_KEY;
863
864 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
865 if (ret < 0)
866 goto out;
867 if (ret > 0) {
868 ret = btrfs_previous_item(root, path, key.objectid, key.type);
869 if (ret < 0)
870 goto out;
871 }
872
873 while (1) {
874 l = path->nodes[0];
875 slot = path->slots[0];
876 if (slot >= btrfs_header_nritems(l)) {
877 ret = btrfs_next_leaf(root, path);
878 if (ret == 0)
879 continue;
880 if (ret < 0)
881 goto out;
882
883 break;
884 }
885 btrfs_item_key_to_cpu(l, &key, slot);
886
887 if (key.objectid < device->devid)
888 goto next;
889
890 if (key.objectid > device->devid)
891 break;
892
893 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
894 goto next;
895
896 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
897 extent_end = key.offset + btrfs_dev_extent_length(l,
898 dev_extent);
899 if (key.offset <= start && extent_end > end) {
900 *length = end - start + 1;
901 break;
902 } else if (key.offset <= start && extent_end > start)
903 *length += extent_end - start;
904 else if (key.offset > start && extent_end <= end)
905 *length += extent_end - key.offset;
906 else if (key.offset > start && key.offset <= end) {
907 *length += end - key.offset + 1;
908 break;
909 } else if (key.offset > end)
910 break;
911
912 next:
913 path->slots[0]++;
914 }
915 ret = 0;
916 out:
917 btrfs_free_path(path);
918 return ret;
919 }
920
921 /*
922 * find_free_dev_extent - find free space in the specified device
923 * @device: the device which we search the free space in
924 * @num_bytes: the size of the free space that we need
925 * @start: store the start of the free space.
926 * @len: the size of the free space. that we find, or the size of the max
927 * free space if we don't find suitable free space
928 *
929 * this uses a pretty simple search, the expectation is that it is
930 * called very infrequently and that a given device has a small number
931 * of extents
932 *
933 * @start is used to store the start of the free space if we find. But if we
934 * don't find suitable free space, it will be used to store the start position
935 * of the max free space.
936 *
937 * @len is used to store the size of the free space that we find.
938 * But if we don't find suitable free space, it is used to store the size of
939 * the max free space.
940 */
941 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
942 u64 *start, u64 *len)
943 {
944 struct btrfs_key key;
945 struct btrfs_root *root = device->dev_root;
946 struct btrfs_dev_extent *dev_extent;
947 struct btrfs_path *path;
948 u64 hole_size;
949 u64 max_hole_start;
950 u64 max_hole_size;
951 u64 extent_end;
952 u64 search_start;
953 u64 search_end = device->total_bytes;
954 int ret;
955 int slot;
956 struct extent_buffer *l;
957
958 /* FIXME use last free of some kind */
959
960 /* we don't want to overwrite the superblock on the drive,
961 * so we make sure to start at an offset of at least 1MB
962 */
963 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
964
965 max_hole_start = search_start;
966 max_hole_size = 0;
967 hole_size = 0;
968
969 if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
970 ret = -ENOSPC;
971 goto error;
972 }
973
974 path = btrfs_alloc_path();
975 if (!path) {
976 ret = -ENOMEM;
977 goto error;
978 }
979 path->reada = 2;
980
981 key.objectid = device->devid;
982 key.offset = search_start;
983 key.type = BTRFS_DEV_EXTENT_KEY;
984
985 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
986 if (ret < 0)
987 goto out;
988 if (ret > 0) {
989 ret = btrfs_previous_item(root, path, key.objectid, key.type);
990 if (ret < 0)
991 goto out;
992 }
993
994 while (1) {
995 l = path->nodes[0];
996 slot = path->slots[0];
997 if (slot >= btrfs_header_nritems(l)) {
998 ret = btrfs_next_leaf(root, path);
999 if (ret == 0)
1000 continue;
1001 if (ret < 0)
1002 goto out;
1003
1004 break;
1005 }
1006 btrfs_item_key_to_cpu(l, &key, slot);
1007
1008 if (key.objectid < device->devid)
1009 goto next;
1010
1011 if (key.objectid > device->devid)
1012 break;
1013
1014 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
1015 goto next;
1016
1017 if (key.offset > search_start) {
1018 hole_size = key.offset - search_start;
1019
1020 if (hole_size > max_hole_size) {
1021 max_hole_start = search_start;
1022 max_hole_size = hole_size;
1023 }
1024
1025 /*
1026 * If this free space is greater than which we need,
1027 * it must be the max free space that we have found
1028 * until now, so max_hole_start must point to the start
1029 * of this free space and the length of this free space
1030 * is stored in max_hole_size. Thus, we return
1031 * max_hole_start and max_hole_size and go back to the
1032 * caller.
1033 */
1034 if (hole_size >= num_bytes) {
1035 ret = 0;
1036 goto out;
1037 }
1038 }
1039
1040 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
1041 extent_end = key.offset + btrfs_dev_extent_length(l,
1042 dev_extent);
1043 if (extent_end > search_start)
1044 search_start = extent_end;
1045 next:
1046 path->slots[0]++;
1047 cond_resched();
1048 }
1049
1050 /*
1051 * At this point, search_start should be the end of
1052 * allocated dev extents, and when shrinking the device,
1053 * search_end may be smaller than search_start.
1054 */
1055 if (search_end > search_start)
1056 hole_size = search_end - search_start;
1057
1058 if (hole_size > max_hole_size) {
1059 max_hole_start = search_start;
1060 max_hole_size = hole_size;
1061 }
1062
1063 /* See above. */
1064 if (hole_size < num_bytes)
1065 ret = -ENOSPC;
1066 else
1067 ret = 0;
1068
1069 out:
1070 btrfs_free_path(path);
1071 error:
1072 *start = max_hole_start;
1073 if (len)
1074 *len = max_hole_size;
1075 return ret;
1076 }
1077
1078 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1079 struct btrfs_device *device,
1080 u64 start)
1081 {
1082 int ret;
1083 struct btrfs_path *path;
1084 struct btrfs_root *root = device->dev_root;
1085 struct btrfs_key key;
1086 struct btrfs_key found_key;
1087 struct extent_buffer *leaf = NULL;
1088 struct btrfs_dev_extent *extent = NULL;
1089
1090 path = btrfs_alloc_path();
1091 if (!path)
1092 return -ENOMEM;
1093
1094 key.objectid = device->devid;
1095 key.offset = start;
1096 key.type = BTRFS_DEV_EXTENT_KEY;
1097 again:
1098 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1099 if (ret > 0) {
1100 ret = btrfs_previous_item(root, path, key.objectid,
1101 BTRFS_DEV_EXTENT_KEY);
1102 if (ret)
1103 goto out;
1104 leaf = path->nodes[0];
1105 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1106 extent = btrfs_item_ptr(leaf, path->slots[0],
1107 struct btrfs_dev_extent);
1108 BUG_ON(found_key.offset > start || found_key.offset +
1109 btrfs_dev_extent_length(leaf, extent) < start);
1110 key = found_key;
1111 btrfs_release_path(path);
1112 goto again;
1113 } else if (ret == 0) {
1114 leaf = path->nodes[0];
1115 extent = btrfs_item_ptr(leaf, path->slots[0],
1116 struct btrfs_dev_extent);
1117 } else {
1118 btrfs_error(root->fs_info, ret, "Slot search failed");
1119 goto out;
1120 }
1121
1122 if (device->bytes_used > 0) {
1123 u64 len = btrfs_dev_extent_length(leaf, extent);
1124 device->bytes_used -= len;
1125 spin_lock(&root->fs_info->free_chunk_lock);
1126 root->fs_info->free_chunk_space += len;
1127 spin_unlock(&root->fs_info->free_chunk_lock);
1128 }
1129 ret = btrfs_del_item(trans, root, path);
1130 if (ret) {
1131 btrfs_error(root->fs_info, ret,
1132 "Failed to remove dev extent item");
1133 }
1134 out:
1135 btrfs_free_path(path);
1136 return ret;
1137 }
1138
1139 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1140 struct btrfs_device *device,
1141 u64 chunk_tree, u64 chunk_objectid,
1142 u64 chunk_offset, u64 start, u64 num_bytes)
1143 {
1144 int ret;
1145 struct btrfs_path *path;
1146 struct btrfs_root *root = device->dev_root;
1147 struct btrfs_dev_extent *extent;
1148 struct extent_buffer *leaf;
1149 struct btrfs_key key;
1150
1151 WARN_ON(!device->in_fs_metadata);
1152 WARN_ON(device->is_tgtdev_for_dev_replace);
1153 path = btrfs_alloc_path();
1154 if (!path)
1155 return -ENOMEM;
1156
1157 key.objectid = device->devid;
1158 key.offset = start;
1159 key.type = BTRFS_DEV_EXTENT_KEY;
1160 ret = btrfs_insert_empty_item(trans, root, path, &key,
1161 sizeof(*extent));
1162 if (ret)
1163 goto out;
1164
1165 leaf = path->nodes[0];
1166 extent = btrfs_item_ptr(leaf, path->slots[0],
1167 struct btrfs_dev_extent);
1168 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1169 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1170 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1171
1172 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1173 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent),
1174 BTRFS_UUID_SIZE);
1175
1176 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1177 btrfs_mark_buffer_dirty(leaf);
1178 out:
1179 btrfs_free_path(path);
1180 return ret;
1181 }
1182
1183 static noinline int find_next_chunk(struct btrfs_root *root,
1184 u64 objectid, u64 *offset)
1185 {
1186 struct btrfs_path *path;
1187 int ret;
1188 struct btrfs_key key;
1189 struct btrfs_chunk *chunk;
1190 struct btrfs_key found_key;
1191
1192 path = btrfs_alloc_path();
1193 if (!path)
1194 return -ENOMEM;
1195
1196 key.objectid = objectid;
1197 key.offset = (u64)-1;
1198 key.type = BTRFS_CHUNK_ITEM_KEY;
1199
1200 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1201 if (ret < 0)
1202 goto error;
1203
1204 BUG_ON(ret == 0); /* Corruption */
1205
1206 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY);
1207 if (ret) {
1208 *offset = 0;
1209 } else {
1210 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1211 path->slots[0]);
1212 if (found_key.objectid != objectid)
1213 *offset = 0;
1214 else {
1215 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
1216 struct btrfs_chunk);
1217 *offset = found_key.offset +
1218 btrfs_chunk_length(path->nodes[0], chunk);
1219 }
1220 }
1221 ret = 0;
1222 error:
1223 btrfs_free_path(path);
1224 return ret;
1225 }
1226
1227 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid)
1228 {
1229 int ret;
1230 struct btrfs_key key;
1231 struct btrfs_key found_key;
1232 struct btrfs_path *path;
1233
1234 root = root->fs_info->chunk_root;
1235
1236 path = btrfs_alloc_path();
1237 if (!path)
1238 return -ENOMEM;
1239
1240 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1241 key.type = BTRFS_DEV_ITEM_KEY;
1242 key.offset = (u64)-1;
1243
1244 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1245 if (ret < 0)
1246 goto error;
1247
1248 BUG_ON(ret == 0); /* Corruption */
1249
1250 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID,
1251 BTRFS_DEV_ITEM_KEY);
1252 if (ret) {
1253 *objectid = 1;
1254 } else {
1255 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1256 path->slots[0]);
1257 *objectid = found_key.offset + 1;
1258 }
1259 ret = 0;
1260 error:
1261 btrfs_free_path(path);
1262 return ret;
1263 }
1264
1265 /*
1266 * the device information is stored in the chunk root
1267 * the btrfs_device struct should be fully filled in
1268 */
1269 int btrfs_add_device(struct btrfs_trans_handle *trans,
1270 struct btrfs_root *root,
1271 struct btrfs_device *device)
1272 {
1273 int ret;
1274 struct btrfs_path *path;
1275 struct btrfs_dev_item *dev_item;
1276 struct extent_buffer *leaf;
1277 struct btrfs_key key;
1278 unsigned long ptr;
1279
1280 root = root->fs_info->chunk_root;
1281
1282 path = btrfs_alloc_path();
1283 if (!path)
1284 return -ENOMEM;
1285
1286 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1287 key.type = BTRFS_DEV_ITEM_KEY;
1288 key.offset = device->devid;
1289
1290 ret = btrfs_insert_empty_item(trans, root, path, &key,
1291 sizeof(*dev_item));
1292 if (ret)
1293 goto out;
1294
1295 leaf = path->nodes[0];
1296 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1297
1298 btrfs_set_device_id(leaf, dev_item, device->devid);
1299 btrfs_set_device_generation(leaf, dev_item, 0);
1300 btrfs_set_device_type(leaf, dev_item, device->type);
1301 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1302 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1303 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1304 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
1305 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1306 btrfs_set_device_group(leaf, dev_item, 0);
1307 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1308 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1309 btrfs_set_device_start_offset(leaf, dev_item, 0);
1310
1311 ptr = (unsigned long)btrfs_device_uuid(dev_item);
1312 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1313 ptr = (unsigned long)btrfs_device_fsid(dev_item);
1314 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1315 btrfs_mark_buffer_dirty(leaf);
1316
1317 ret = 0;
1318 out:
1319 btrfs_free_path(path);
1320 return ret;
1321 }
1322
1323 static int btrfs_rm_dev_item(struct btrfs_root *root,
1324 struct btrfs_device *device)
1325 {
1326 int ret;
1327 struct btrfs_path *path;
1328 struct btrfs_key key;
1329 struct btrfs_trans_handle *trans;
1330
1331 root = root->fs_info->chunk_root;
1332
1333 path = btrfs_alloc_path();
1334 if (!path)
1335 return -ENOMEM;
1336
1337 trans = btrfs_start_transaction(root, 0);
1338 if (IS_ERR(trans)) {
1339 btrfs_free_path(path);
1340 return PTR_ERR(trans);
1341 }
1342 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1343 key.type = BTRFS_DEV_ITEM_KEY;
1344 key.offset = device->devid;
1345 lock_chunks(root);
1346
1347 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1348 if (ret < 0)
1349 goto out;
1350
1351 if (ret > 0) {
1352 ret = -ENOENT;
1353 goto out;
1354 }
1355
1356 ret = btrfs_del_item(trans, root, path);
1357 if (ret)
1358 goto out;
1359 out:
1360 btrfs_free_path(path);
1361 unlock_chunks(root);
1362 btrfs_commit_transaction(trans, root);
1363 return ret;
1364 }
1365
1366 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1367 {
1368 struct btrfs_device *device;
1369 struct btrfs_device *next_device;
1370 struct block_device *bdev;
1371 struct buffer_head *bh = NULL;
1372 struct btrfs_super_block *disk_super;
1373 struct btrfs_fs_devices *cur_devices;
1374 u64 all_avail;
1375 u64 devid;
1376 u64 num_devices;
1377 u8 *dev_uuid;
1378 int ret = 0;
1379 bool clear_super = false;
1380
1381 mutex_lock(&uuid_mutex);
1382
1383 all_avail = root->fs_info->avail_data_alloc_bits |
1384 root->fs_info->avail_system_alloc_bits |
1385 root->fs_info->avail_metadata_alloc_bits;
1386
1387 num_devices = root->fs_info->fs_devices->num_devices;
1388 btrfs_dev_replace_lock(&root->fs_info->dev_replace);
1389 if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
1390 WARN_ON(num_devices < 1);
1391 num_devices--;
1392 }
1393 btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
1394
1395 if ((all_avail & (BTRFS_BLOCK_GROUP_RAID5 |
1396 BTRFS_BLOCK_GROUP_RAID6) && num_devices <= 3)) {
1397 printk(KERN_ERR "btrfs: unable to go below three devices "
1398 "on raid5 or raid6\n");
1399 ret = -EINVAL;
1400 goto out;
1401 }
1402
1403 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
1404 printk(KERN_ERR "btrfs: unable to go below four devices "
1405 "on raid10\n");
1406 ret = -EINVAL;
1407 goto out;
1408 }
1409
1410 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
1411 printk(KERN_ERR "btrfs: unable to go below two "
1412 "devices on raid1\n");
1413 ret = -EINVAL;
1414 goto out;
1415 }
1416
1417 if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
1418 root->fs_info->fs_devices->rw_devices <= 2) {
1419 printk(KERN_ERR "btrfs: unable to go below two "
1420 "devices on raid5\n");
1421 ret = -EINVAL;
1422 goto out;
1423 }
1424 if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
1425 root->fs_info->fs_devices->rw_devices <= 3) {
1426 printk(KERN_ERR "btrfs: unable to go below three "
1427 "devices on raid6\n");
1428 ret = -EINVAL;
1429 goto out;
1430 }
1431
1432 if (strcmp(device_path, "missing") == 0) {
1433 struct list_head *devices;
1434 struct btrfs_device *tmp;
1435
1436 device = NULL;
1437 devices = &root->fs_info->fs_devices->devices;
1438 /*
1439 * It is safe to read the devices since the volume_mutex
1440 * is held.
1441 */
1442 list_for_each_entry(tmp, devices, dev_list) {
1443 if (tmp->in_fs_metadata &&
1444 !tmp->is_tgtdev_for_dev_replace &&
1445 !tmp->bdev) {
1446 device = tmp;
1447 break;
1448 }
1449 }
1450 bdev = NULL;
1451 bh = NULL;
1452 disk_super = NULL;
1453 if (!device) {
1454 printk(KERN_ERR "btrfs: no missing devices found to "
1455 "remove\n");
1456 goto out;
1457 }
1458 } else {
1459 ret = btrfs_get_bdev_and_sb(device_path,
1460 FMODE_READ | FMODE_EXCL,
1461 root->fs_info->bdev_holder, 0,
1462 &bdev, &bh);
1463 if (ret)
1464 goto out;
1465 disk_super = (struct btrfs_super_block *)bh->b_data;
1466 devid = btrfs_stack_device_id(&disk_super->dev_item);
1467 dev_uuid = disk_super->dev_item.uuid;
1468 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1469 disk_super->fsid);
1470 if (!device) {
1471 ret = -ENOENT;
1472 goto error_brelse;
1473 }
1474 }
1475
1476 if (device->is_tgtdev_for_dev_replace) {
1477 pr_err("btrfs: unable to remove the dev_replace target dev\n");
1478 ret = -EINVAL;
1479 goto error_brelse;
1480 }
1481
1482 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1483 printk(KERN_ERR "btrfs: unable to remove the only writeable "
1484 "device\n");
1485 ret = -EINVAL;
1486 goto error_brelse;
1487 }
1488
1489 if (device->writeable) {
1490 lock_chunks(root);
1491 list_del_init(&device->dev_alloc_list);
1492 unlock_chunks(root);
1493 root->fs_info->fs_devices->rw_devices--;
1494 clear_super = true;
1495 }
1496
1497 ret = btrfs_shrink_device(device, 0);
1498 if (ret)
1499 goto error_undo;
1500
1501 /*
1502 * TODO: the superblock still includes this device in its num_devices
1503 * counter although write_all_supers() is not locked out. This
1504 * could give a filesystem state which requires a degraded mount.
1505 */
1506 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1507 if (ret)
1508 goto error_undo;
1509
1510 spin_lock(&root->fs_info->free_chunk_lock);
1511 root->fs_info->free_chunk_space = device->total_bytes -
1512 device->bytes_used;
1513 spin_unlock(&root->fs_info->free_chunk_lock);
1514
1515 device->in_fs_metadata = 0;
1516 btrfs_scrub_cancel_dev(root->fs_info, device);
1517
1518 /*
1519 * the device list mutex makes sure that we don't change
1520 * the device list while someone else is writing out all
1521 * the device supers.
1522 */
1523
1524 cur_devices = device->fs_devices;
1525 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1526 list_del_rcu(&device->dev_list);
1527
1528 device->fs_devices->num_devices--;
1529 device->fs_devices->total_devices--;
1530
1531 if (device->missing)
1532 root->fs_info->fs_devices->missing_devices--;
1533
1534 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1535 struct btrfs_device, dev_list);
1536 if (device->bdev == root->fs_info->sb->s_bdev)
1537 root->fs_info->sb->s_bdev = next_device->bdev;
1538 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1539 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1540
1541 if (device->bdev)
1542 device->fs_devices->open_devices--;
1543
1544 call_rcu(&device->rcu, free_device);
1545 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1546
1547 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1548 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1549
1550 if (cur_devices->open_devices == 0) {
1551 struct btrfs_fs_devices *fs_devices;
1552 fs_devices = root->fs_info->fs_devices;
1553 while (fs_devices) {
1554 if (fs_devices->seed == cur_devices)
1555 break;
1556 fs_devices = fs_devices->seed;
1557 }
1558 fs_devices->seed = cur_devices->seed;
1559 cur_devices->seed = NULL;
1560 lock_chunks(root);
1561 __btrfs_close_devices(cur_devices);
1562 unlock_chunks(root);
1563 free_fs_devices(cur_devices);
1564 }
1565
1566 root->fs_info->num_tolerated_disk_barrier_failures =
1567 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
1568
1569 /*
1570 * at this point, the device is zero sized. We want to
1571 * remove it from the devices list and zero out the old super
1572 */
1573 if (clear_super && disk_super) {
1574 /* make sure this device isn't detected as part of
1575 * the FS anymore
1576 */
1577 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1578 set_buffer_dirty(bh);
1579 sync_dirty_buffer(bh);
1580 }
1581
1582 ret = 0;
1583
1584 /* Notify udev that device has changed */
1585 if (bdev)
1586 btrfs_kobject_uevent(bdev, KOBJ_CHANGE);
1587
1588 error_brelse:
1589 brelse(bh);
1590 if (bdev)
1591 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1592 out:
1593 mutex_unlock(&uuid_mutex);
1594 return ret;
1595 error_undo:
1596 if (device->writeable) {
1597 lock_chunks(root);
1598 list_add(&device->dev_alloc_list,
1599 &root->fs_info->fs_devices->alloc_list);
1600 unlock_chunks(root);
1601 root->fs_info->fs_devices->rw_devices++;
1602 }
1603 goto error_brelse;
1604 }
1605
1606 void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info,
1607 struct btrfs_device *srcdev)
1608 {
1609 WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex));
1610 list_del_rcu(&srcdev->dev_list);
1611 list_del_rcu(&srcdev->dev_alloc_list);
1612 fs_info->fs_devices->num_devices--;
1613 if (srcdev->missing) {
1614 fs_info->fs_devices->missing_devices--;
1615 fs_info->fs_devices->rw_devices++;
1616 }
1617 if (srcdev->can_discard)
1618 fs_info->fs_devices->num_can_discard--;
1619 if (srcdev->bdev)
1620 fs_info->fs_devices->open_devices--;
1621
1622 call_rcu(&srcdev->rcu, free_device);
1623 }
1624
1625 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
1626 struct btrfs_device *tgtdev)
1627 {
1628 struct btrfs_device *next_device;
1629
1630 WARN_ON(!tgtdev);
1631 mutex_lock(&fs_info->fs_devices->device_list_mutex);
1632 if (tgtdev->bdev) {
1633 btrfs_scratch_superblock(tgtdev);
1634 fs_info->fs_devices->open_devices--;
1635 }
1636 fs_info->fs_devices->num_devices--;
1637 if (tgtdev->can_discard)
1638 fs_info->fs_devices->num_can_discard++;
1639
1640 next_device = list_entry(fs_info->fs_devices->devices.next,
1641 struct btrfs_device, dev_list);
1642 if (tgtdev->bdev == fs_info->sb->s_bdev)
1643 fs_info->sb->s_bdev = next_device->bdev;
1644 if (tgtdev->bdev == fs_info->fs_devices->latest_bdev)
1645 fs_info->fs_devices->latest_bdev = next_device->bdev;
1646 list_del_rcu(&tgtdev->dev_list);
1647
1648 call_rcu(&tgtdev->rcu, free_device);
1649
1650 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
1651 }
1652
1653 int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path,
1654 struct btrfs_device **device)
1655 {
1656 int ret = 0;
1657 struct btrfs_super_block *disk_super;
1658 u64 devid;
1659 u8 *dev_uuid;
1660 struct block_device *bdev;
1661 struct buffer_head *bh;
1662
1663 *device = NULL;
1664 ret = btrfs_get_bdev_and_sb(device_path, FMODE_READ,
1665 root->fs_info->bdev_holder, 0, &bdev, &bh);
1666 if (ret)
1667 return ret;
1668 disk_super = (struct btrfs_super_block *)bh->b_data;
1669 devid = btrfs_stack_device_id(&disk_super->dev_item);
1670 dev_uuid = disk_super->dev_item.uuid;
1671 *device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1672 disk_super->fsid);
1673 brelse(bh);
1674 if (!*device)
1675 ret = -ENOENT;
1676 blkdev_put(bdev, FMODE_READ);
1677 return ret;
1678 }
1679
1680 int btrfs_find_device_missing_or_by_path(struct btrfs_root *root,
1681 char *device_path,
1682 struct btrfs_device **device)
1683 {
1684 *device = NULL;
1685 if (strcmp(device_path, "missing") == 0) {
1686 struct list_head *devices;
1687 struct btrfs_device *tmp;
1688
1689 devices = &root->fs_info->fs_devices->devices;
1690 /*
1691 * It is safe to read the devices since the volume_mutex
1692 * is held by the caller.
1693 */
1694 list_for_each_entry(tmp, devices, dev_list) {
1695 if (tmp->in_fs_metadata && !tmp->bdev) {
1696 *device = tmp;
1697 break;
1698 }
1699 }
1700
1701 if (!*device) {
1702 pr_err("btrfs: no missing device found\n");
1703 return -ENOENT;
1704 }
1705
1706 return 0;
1707 } else {
1708 return btrfs_find_device_by_path(root, device_path, device);
1709 }
1710 }
1711
1712 /*
1713 * does all the dirty work required for changing file system's UUID.
1714 */
1715 static int btrfs_prepare_sprout(struct btrfs_root *root)
1716 {
1717 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1718 struct btrfs_fs_devices *old_devices;
1719 struct btrfs_fs_devices *seed_devices;
1720 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
1721 struct btrfs_device *device;
1722 u64 super_flags;
1723
1724 BUG_ON(!mutex_is_locked(&uuid_mutex));
1725 if (!fs_devices->seeding)
1726 return -EINVAL;
1727
1728 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
1729 if (!seed_devices)
1730 return -ENOMEM;
1731
1732 old_devices = clone_fs_devices(fs_devices);
1733 if (IS_ERR(old_devices)) {
1734 kfree(seed_devices);
1735 return PTR_ERR(old_devices);
1736 }
1737
1738 list_add(&old_devices->list, &fs_uuids);
1739
1740 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1741 seed_devices->opened = 1;
1742 INIT_LIST_HEAD(&seed_devices->devices);
1743 INIT_LIST_HEAD(&seed_devices->alloc_list);
1744 mutex_init(&seed_devices->device_list_mutex);
1745
1746 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1747 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
1748 synchronize_rcu);
1749 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1750
1751 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1752 list_for_each_entry(device, &seed_devices->devices, dev_list) {
1753 device->fs_devices = seed_devices;
1754 }
1755
1756 fs_devices->seeding = 0;
1757 fs_devices->num_devices = 0;
1758 fs_devices->open_devices = 0;
1759 fs_devices->total_devices = 0;
1760 fs_devices->seed = seed_devices;
1761
1762 generate_random_uuid(fs_devices->fsid);
1763 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1764 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1765 super_flags = btrfs_super_flags(disk_super) &
1766 ~BTRFS_SUPER_FLAG_SEEDING;
1767 btrfs_set_super_flags(disk_super, super_flags);
1768
1769 return 0;
1770 }
1771
1772 /*
1773 * strore the expected generation for seed devices in device items.
1774 */
1775 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
1776 struct btrfs_root *root)
1777 {
1778 struct btrfs_path *path;
1779 struct extent_buffer *leaf;
1780 struct btrfs_dev_item *dev_item;
1781 struct btrfs_device *device;
1782 struct btrfs_key key;
1783 u8 fs_uuid[BTRFS_UUID_SIZE];
1784 u8 dev_uuid[BTRFS_UUID_SIZE];
1785 u64 devid;
1786 int ret;
1787
1788 path = btrfs_alloc_path();
1789 if (!path)
1790 return -ENOMEM;
1791
1792 root = root->fs_info->chunk_root;
1793 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1794 key.offset = 0;
1795 key.type = BTRFS_DEV_ITEM_KEY;
1796
1797 while (1) {
1798 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1799 if (ret < 0)
1800 goto error;
1801
1802 leaf = path->nodes[0];
1803 next_slot:
1804 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1805 ret = btrfs_next_leaf(root, path);
1806 if (ret > 0)
1807 break;
1808 if (ret < 0)
1809 goto error;
1810 leaf = path->nodes[0];
1811 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1812 btrfs_release_path(path);
1813 continue;
1814 }
1815
1816 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1817 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
1818 key.type != BTRFS_DEV_ITEM_KEY)
1819 break;
1820
1821 dev_item = btrfs_item_ptr(leaf, path->slots[0],
1822 struct btrfs_dev_item);
1823 devid = btrfs_device_id(leaf, dev_item);
1824 read_extent_buffer(leaf, dev_uuid,
1825 (unsigned long)btrfs_device_uuid(dev_item),
1826 BTRFS_UUID_SIZE);
1827 read_extent_buffer(leaf, fs_uuid,
1828 (unsigned long)btrfs_device_fsid(dev_item),
1829 BTRFS_UUID_SIZE);
1830 device = btrfs_find_device(root->fs_info, devid, dev_uuid,
1831 fs_uuid);
1832 BUG_ON(!device); /* Logic error */
1833
1834 if (device->fs_devices->seeding) {
1835 btrfs_set_device_generation(leaf, dev_item,
1836 device->generation);
1837 btrfs_mark_buffer_dirty(leaf);
1838 }
1839
1840 path->slots[0]++;
1841 goto next_slot;
1842 }
1843 ret = 0;
1844 error:
1845 btrfs_free_path(path);
1846 return ret;
1847 }
1848
1849 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
1850 {
1851 struct request_queue *q;
1852 struct btrfs_trans_handle *trans;
1853 struct btrfs_device *device;
1854 struct block_device *bdev;
1855 struct list_head *devices;
1856 struct super_block *sb = root->fs_info->sb;
1857 struct rcu_string *name;
1858 u64 total_bytes;
1859 int seeding_dev = 0;
1860 int ret = 0;
1861
1862 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
1863 return -EROFS;
1864
1865 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
1866 root->fs_info->bdev_holder);
1867 if (IS_ERR(bdev))
1868 return PTR_ERR(bdev);
1869
1870 if (root->fs_info->fs_devices->seeding) {
1871 seeding_dev = 1;
1872 down_write(&sb->s_umount);
1873 mutex_lock(&uuid_mutex);
1874 }
1875
1876 filemap_write_and_wait(bdev->bd_inode->i_mapping);
1877
1878 devices = &root->fs_info->fs_devices->devices;
1879
1880 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1881 list_for_each_entry(device, devices, dev_list) {
1882 if (device->bdev == bdev) {
1883 ret = -EEXIST;
1884 mutex_unlock(
1885 &root->fs_info->fs_devices->device_list_mutex);
1886 goto error;
1887 }
1888 }
1889 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1890
1891 device = kzalloc(sizeof(*device), GFP_NOFS);
1892 if (!device) {
1893 /* we can safely leave the fs_devices entry around */
1894 ret = -ENOMEM;
1895 goto error;
1896 }
1897
1898 name = rcu_string_strdup(device_path, GFP_NOFS);
1899 if (!name) {
1900 kfree(device);
1901 ret = -ENOMEM;
1902 goto error;
1903 }
1904 rcu_assign_pointer(device->name, name);
1905
1906 ret = find_next_devid(root, &device->devid);
1907 if (ret) {
1908 rcu_string_free(device->name);
1909 kfree(device);
1910 goto error;
1911 }
1912
1913 trans = btrfs_start_transaction(root, 0);
1914 if (IS_ERR(trans)) {
1915 rcu_string_free(device->name);
1916 kfree(device);
1917 ret = PTR_ERR(trans);
1918 goto error;
1919 }
1920
1921 lock_chunks(root);
1922
1923 q = bdev_get_queue(bdev);
1924 if (blk_queue_discard(q))
1925 device->can_discard = 1;
1926 device->writeable = 1;
1927 device->work.func = pending_bios_fn;
1928 generate_random_uuid(device->uuid);
1929 spin_lock_init(&device->io_lock);
1930 device->generation = trans->transid;
1931 device->io_width = root->sectorsize;
1932 device->io_align = root->sectorsize;
1933 device->sector_size = root->sectorsize;
1934 device->total_bytes = i_size_read(bdev->bd_inode);
1935 device->disk_total_bytes = device->total_bytes;
1936 device->dev_root = root->fs_info->dev_root;
1937 device->bdev = bdev;
1938 device->in_fs_metadata = 1;
1939 device->is_tgtdev_for_dev_replace = 0;
1940 device->mode = FMODE_EXCL;
1941 set_blocksize(device->bdev, 4096);
1942
1943 if (seeding_dev) {
1944 sb->s_flags &= ~MS_RDONLY;
1945 ret = btrfs_prepare_sprout(root);
1946 BUG_ON(ret); /* -ENOMEM */
1947 }
1948
1949 device->fs_devices = root->fs_info->fs_devices;
1950
1951 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1952 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
1953 list_add(&device->dev_alloc_list,
1954 &root->fs_info->fs_devices->alloc_list);
1955 root->fs_info->fs_devices->num_devices++;
1956 root->fs_info->fs_devices->open_devices++;
1957 root->fs_info->fs_devices->rw_devices++;
1958 root->fs_info->fs_devices->total_devices++;
1959 if (device->can_discard)
1960 root->fs_info->fs_devices->num_can_discard++;
1961 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
1962
1963 spin_lock(&root->fs_info->free_chunk_lock);
1964 root->fs_info->free_chunk_space += device->total_bytes;
1965 spin_unlock(&root->fs_info->free_chunk_lock);
1966
1967 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
1968 root->fs_info->fs_devices->rotating = 1;
1969
1970 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
1971 btrfs_set_super_total_bytes(root->fs_info->super_copy,
1972 total_bytes + device->total_bytes);
1973
1974 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy);
1975 btrfs_set_super_num_devices(root->fs_info->super_copy,
1976 total_bytes + 1);
1977 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1978
1979 if (seeding_dev) {
1980 ret = init_first_rw_device(trans, root, device);
1981 if (ret) {
1982 btrfs_abort_transaction(trans, root, ret);
1983 goto error_trans;
1984 }
1985 ret = btrfs_finish_sprout(trans, root);
1986 if (ret) {
1987 btrfs_abort_transaction(trans, root, ret);
1988 goto error_trans;
1989 }
1990 } else {
1991 ret = btrfs_add_device(trans, root, device);
1992 if (ret) {
1993 btrfs_abort_transaction(trans, root, ret);
1994 goto error_trans;
1995 }
1996 }
1997
1998 /*
1999 * we've got more storage, clear any full flags on the space
2000 * infos
2001 */
2002 btrfs_clear_space_info_full(root->fs_info);
2003
2004 unlock_chunks(root);
2005 root->fs_info->num_tolerated_disk_barrier_failures =
2006 btrfs_calc_num_tolerated_disk_barrier_failures(root->fs_info);
2007 ret = btrfs_commit_transaction(trans, root);
2008
2009 if (seeding_dev) {
2010 mutex_unlock(&uuid_mutex);
2011 up_write(&sb->s_umount);
2012
2013 if (ret) /* transaction commit */
2014 return ret;
2015
2016 ret = btrfs_relocate_sys_chunks(root);
2017 if (ret < 0)
2018 btrfs_error(root->fs_info, ret,
2019 "Failed to relocate sys chunks after "
2020 "device initialization. This can be fixed "
2021 "using the \"btrfs balance\" command.");
2022 trans = btrfs_attach_transaction(root);
2023 if (IS_ERR(trans)) {
2024 if (PTR_ERR(trans) == -ENOENT)
2025 return 0;
2026 return PTR_ERR(trans);
2027 }
2028 ret = btrfs_commit_transaction(trans, root);
2029 }
2030
2031 return ret;
2032
2033 error_trans:
2034 unlock_chunks(root);
2035 btrfs_end_transaction(trans, root);
2036 rcu_string_free(device->name);
2037 kfree(device);
2038 error:
2039 blkdev_put(bdev, FMODE_EXCL);
2040 if (seeding_dev) {
2041 mutex_unlock(&uuid_mutex);
2042 up_write(&sb->s_umount);
2043 }
2044 return ret;
2045 }
2046
2047 int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path,
2048 struct btrfs_device **device_out)
2049 {
2050 struct request_queue *q;
2051 struct btrfs_device *device;
2052 struct block_device *bdev;
2053 struct btrfs_fs_info *fs_info = root->fs_info;
2054 struct list_head *devices;
2055 struct rcu_string *name;
2056 int ret = 0;
2057
2058 *device_out = NULL;
2059 if (fs_info->fs_devices->seeding)
2060 return -EINVAL;
2061
2062 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
2063 fs_info->bdev_holder);
2064 if (IS_ERR(bdev))
2065 return PTR_ERR(bdev);
2066
2067 filemap_write_and_wait(bdev->bd_inode->i_mapping);
2068
2069 devices = &fs_info->fs_devices->devices;
2070 list_for_each_entry(device, devices, dev_list) {
2071 if (device->bdev == bdev) {
2072 ret = -EEXIST;
2073 goto error;
2074 }
2075 }
2076
2077 device = kzalloc(sizeof(*device), GFP_NOFS);
2078 if (!device) {
2079 ret = -ENOMEM;
2080 goto error;
2081 }
2082
2083 name = rcu_string_strdup(device_path, GFP_NOFS);
2084 if (!name) {
2085 kfree(device);
2086 ret = -ENOMEM;
2087 goto error;
2088 }
2089 rcu_assign_pointer(device->name, name);
2090
2091 q = bdev_get_queue(bdev);
2092 if (blk_queue_discard(q))
2093 device->can_discard = 1;
2094 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2095 device->writeable = 1;
2096 device->work.func = pending_bios_fn;
2097 generate_random_uuid(device->uuid);
2098 device->devid = BTRFS_DEV_REPLACE_DEVID;
2099 spin_lock_init(&device->io_lock);
2100 device->generation = 0;
2101 device->io_width = root->sectorsize;
2102 device->io_align = root->sectorsize;
2103 device->sector_size = root->sectorsize;
2104 device->total_bytes = i_size_read(bdev->bd_inode);
2105 device->disk_total_bytes = device->total_bytes;
2106 device->dev_root = fs_info->dev_root;
2107 device->bdev = bdev;
2108 device->in_fs_metadata = 1;
2109 device->is_tgtdev_for_dev_replace = 1;
2110 device->mode = FMODE_EXCL;
2111 set_blocksize(device->bdev, 4096);
2112 device->fs_devices = fs_info->fs_devices;
2113 list_add(&device->dev_list, &fs_info->fs_devices->devices);
2114 fs_info->fs_devices->num_devices++;
2115 fs_info->fs_devices->open_devices++;
2116 if (device->can_discard)
2117 fs_info->fs_devices->num_can_discard++;
2118 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2119
2120 *device_out = device;
2121 return ret;
2122
2123 error:
2124 blkdev_put(bdev, FMODE_EXCL);
2125 return ret;
2126 }
2127
2128 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info,
2129 struct btrfs_device *tgtdev)
2130 {
2131 WARN_ON(fs_info->fs_devices->rw_devices == 0);
2132 tgtdev->io_width = fs_info->dev_root->sectorsize;
2133 tgtdev->io_align = fs_info->dev_root->sectorsize;
2134 tgtdev->sector_size = fs_info->dev_root->sectorsize;
2135 tgtdev->dev_root = fs_info->dev_root;
2136 tgtdev->in_fs_metadata = 1;
2137 }
2138
2139 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
2140 struct btrfs_device *device)
2141 {
2142 int ret;
2143 struct btrfs_path *path;
2144 struct btrfs_root *root;
2145 struct btrfs_dev_item *dev_item;
2146 struct extent_buffer *leaf;
2147 struct btrfs_key key;
2148
2149 root = device->dev_root->fs_info->chunk_root;
2150
2151 path = btrfs_alloc_path();
2152 if (!path)
2153 return -ENOMEM;
2154
2155 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
2156 key.type = BTRFS_DEV_ITEM_KEY;
2157 key.offset = device->devid;
2158
2159 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
2160 if (ret < 0)
2161 goto out;
2162
2163 if (ret > 0) {
2164 ret = -ENOENT;
2165 goto out;
2166 }
2167
2168 leaf = path->nodes[0];
2169 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
2170
2171 btrfs_set_device_id(leaf, dev_item, device->devid);
2172 btrfs_set_device_type(leaf, dev_item, device->type);
2173 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
2174 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
2175 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
2176 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes);
2177 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
2178 btrfs_mark_buffer_dirty(leaf);
2179
2180 out:
2181 btrfs_free_path(path);
2182 return ret;
2183 }
2184
2185 static int __btrfs_grow_device(struct btrfs_trans_handle *trans,
2186 struct btrfs_device *device, u64 new_size)
2187 {
2188 struct btrfs_super_block *super_copy =
2189 device->dev_root->fs_info->super_copy;
2190 u64 old_total = btrfs_super_total_bytes(super_copy);
2191 u64 diff = new_size - device->total_bytes;
2192
2193 if (!device->writeable)
2194 return -EACCES;
2195 if (new_size <= device->total_bytes ||
2196 device->is_tgtdev_for_dev_replace)
2197 return -EINVAL;
2198
2199 btrfs_set_super_total_bytes(super_copy, old_total + diff);
2200 device->fs_devices->total_rw_bytes += diff;
2201
2202 device->total_bytes = new_size;
2203 device->disk_total_bytes = new_size;
2204 btrfs_clear_space_info_full(device->dev_root->fs_info);
2205
2206 return btrfs_update_device(trans, device);
2207 }
2208
2209 int btrfs_grow_device(struct btrfs_trans_handle *trans,
2210 struct btrfs_device *device, u64 new_size)
2211 {
2212 int ret;
2213 lock_chunks(device->dev_root);
2214 ret = __btrfs_grow_device(trans, device, new_size);
2215 unlock_chunks(device->dev_root);
2216 return ret;
2217 }
2218
2219 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
2220 struct btrfs_root *root,
2221 u64 chunk_tree, u64 chunk_objectid,
2222 u64 chunk_offset)
2223 {
2224 int ret;
2225 struct btrfs_path *path;
2226 struct btrfs_key key;
2227
2228 root = root->fs_info->chunk_root;
2229 path = btrfs_alloc_path();
2230 if (!path)
2231 return -ENOMEM;
2232
2233 key.objectid = chunk_objectid;
2234 key.offset = chunk_offset;
2235 key.type = BTRFS_CHUNK_ITEM_KEY;
2236
2237 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2238 if (ret < 0)
2239 goto out;
2240 else if (ret > 0) { /* Logic error or corruption */
2241 btrfs_error(root->fs_info, -ENOENT,
2242 "Failed lookup while freeing chunk.");
2243 ret = -ENOENT;
2244 goto out;
2245 }
2246
2247 ret = btrfs_del_item(trans, root, path);
2248 if (ret < 0)
2249 btrfs_error(root->fs_info, ret,
2250 "Failed to delete chunk item.");
2251 out:
2252 btrfs_free_path(path);
2253 return ret;
2254 }
2255
2256 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
2257 chunk_offset)
2258 {
2259 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2260 struct btrfs_disk_key *disk_key;
2261 struct btrfs_chunk *chunk;
2262 u8 *ptr;
2263 int ret = 0;
2264 u32 num_stripes;
2265 u32 array_size;
2266 u32 len = 0;
2267 u32 cur;
2268 struct btrfs_key key;
2269
2270 array_size = btrfs_super_sys_array_size(super_copy);
2271
2272 ptr = super_copy->sys_chunk_array;
2273 cur = 0;
2274
2275 while (cur < array_size) {
2276 disk_key = (struct btrfs_disk_key *)ptr;
2277 btrfs_disk_key_to_cpu(&key, disk_key);
2278
2279 len = sizeof(*disk_key);
2280
2281 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
2282 chunk = (struct btrfs_chunk *)(ptr + len);
2283 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
2284 len += btrfs_chunk_item_size(num_stripes);
2285 } else {
2286 ret = -EIO;
2287 break;
2288 }
2289 if (key.objectid == chunk_objectid &&
2290 key.offset == chunk_offset) {
2291 memmove(ptr, ptr + len, array_size - (cur + len));
2292 array_size -= len;
2293 btrfs_set_super_sys_array_size(super_copy, array_size);
2294 } else {
2295 ptr += len;
2296 cur += len;
2297 }
2298 }
2299 return ret;
2300 }
2301
2302 static int btrfs_relocate_chunk(struct btrfs_root *root,
2303 u64 chunk_tree, u64 chunk_objectid,
2304 u64 chunk_offset)
2305 {
2306 struct extent_map_tree *em_tree;
2307 struct btrfs_root *extent_root;
2308 struct btrfs_trans_handle *trans;
2309 struct extent_map *em;
2310 struct map_lookup *map;
2311 int ret;
2312 int i;
2313
2314 root = root->fs_info->chunk_root;
2315 extent_root = root->fs_info->extent_root;
2316 em_tree = &root->fs_info->mapping_tree.map_tree;
2317
2318 ret = btrfs_can_relocate(extent_root, chunk_offset);
2319 if (ret)
2320 return -ENOSPC;
2321
2322 /* step one, relocate all the extents inside this chunk */
2323 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
2324 if (ret)
2325 return ret;
2326
2327 trans = btrfs_start_transaction(root, 0);
2328 BUG_ON(IS_ERR(trans));
2329
2330 lock_chunks(root);
2331
2332 /*
2333 * step two, delete the device extents and the
2334 * chunk tree entries
2335 */
2336 read_lock(&em_tree->lock);
2337 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
2338 read_unlock(&em_tree->lock);
2339
2340 BUG_ON(!em || em->start > chunk_offset ||
2341 em->start + em->len < chunk_offset);
2342 map = (struct map_lookup *)em->bdev;
2343
2344 for (i = 0; i < map->num_stripes; i++) {
2345 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev,
2346 map->stripes[i].physical);
2347 BUG_ON(ret);
2348
2349 if (map->stripes[i].dev) {
2350 ret = btrfs_update_device(trans, map->stripes[i].dev);
2351 BUG_ON(ret);
2352 }
2353 }
2354 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
2355 chunk_offset);
2356
2357 BUG_ON(ret);
2358
2359 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
2360
2361 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
2362 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
2363 BUG_ON(ret);
2364 }
2365
2366 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset);
2367 BUG_ON(ret);
2368
2369 write_lock(&em_tree->lock);
2370 remove_extent_mapping(em_tree, em);
2371 write_unlock(&em_tree->lock);
2372
2373 kfree(map);
2374 em->bdev = NULL;
2375
2376 /* once for the tree */
2377 free_extent_map(em);
2378 /* once for us */
2379 free_extent_map(em);
2380
2381 unlock_chunks(root);
2382 btrfs_end_transaction(trans, root);
2383 return 0;
2384 }
2385
2386 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2387 {
2388 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2389 struct btrfs_path *path;
2390 struct extent_buffer *leaf;
2391 struct btrfs_chunk *chunk;
2392 struct btrfs_key key;
2393 struct btrfs_key found_key;
2394 u64 chunk_tree = chunk_root->root_key.objectid;
2395 u64 chunk_type;
2396 bool retried = false;
2397 int failed = 0;
2398 int ret;
2399
2400 path = btrfs_alloc_path();
2401 if (!path)
2402 return -ENOMEM;
2403
2404 again:
2405 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2406 key.offset = (u64)-1;
2407 key.type = BTRFS_CHUNK_ITEM_KEY;
2408
2409 while (1) {
2410 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2411 if (ret < 0)
2412 goto error;
2413 BUG_ON(ret == 0); /* Corruption */
2414
2415 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2416 key.type);
2417 if (ret < 0)
2418 goto error;
2419 if (ret > 0)
2420 break;
2421
2422 leaf = path->nodes[0];
2423 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2424
2425 chunk = btrfs_item_ptr(leaf, path->slots[0],
2426 struct btrfs_chunk);
2427 chunk_type = btrfs_chunk_type(leaf, chunk);
2428 btrfs_release_path(path);
2429
2430 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2431 ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
2432 found_key.objectid,
2433 found_key.offset);
2434 if (ret == -ENOSPC)
2435 failed++;
2436 else if (ret)
2437 BUG();
2438 }
2439
2440 if (found_key.offset == 0)
2441 break;
2442 key.offset = found_key.offset - 1;
2443 }
2444 ret = 0;
2445 if (failed && !retried) {
2446 failed = 0;
2447 retried = true;
2448 goto again;
2449 } else if (failed && retried) {
2450 WARN_ON(1);
2451 ret = -ENOSPC;
2452 }
2453 error:
2454 btrfs_free_path(path);
2455 return ret;
2456 }
2457
2458 static int insert_balance_item(struct btrfs_root *root,
2459 struct btrfs_balance_control *bctl)
2460 {
2461 struct btrfs_trans_handle *trans;
2462 struct btrfs_balance_item *item;
2463 struct btrfs_disk_balance_args disk_bargs;
2464 struct btrfs_path *path;
2465 struct extent_buffer *leaf;
2466 struct btrfs_key key;
2467 int ret, err;
2468
2469 path = btrfs_alloc_path();
2470 if (!path)
2471 return -ENOMEM;
2472
2473 trans = btrfs_start_transaction(root, 0);
2474 if (IS_ERR(trans)) {
2475 btrfs_free_path(path);
2476 return PTR_ERR(trans);
2477 }
2478
2479 key.objectid = BTRFS_BALANCE_OBJECTID;
2480 key.type = BTRFS_BALANCE_ITEM_KEY;
2481 key.offset = 0;
2482
2483 ret = btrfs_insert_empty_item(trans, root, path, &key,
2484 sizeof(*item));
2485 if (ret)
2486 goto out;
2487
2488 leaf = path->nodes[0];
2489 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2490
2491 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2492
2493 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2494 btrfs_set_balance_data(leaf, item, &disk_bargs);
2495 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2496 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2497 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2498 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2499
2500 btrfs_set_balance_flags(leaf, item, bctl->flags);
2501
2502 btrfs_mark_buffer_dirty(leaf);
2503 out:
2504 btrfs_free_path(path);
2505 err = btrfs_commit_transaction(trans, root);
2506 if (err && !ret)
2507 ret = err;
2508 return ret;
2509 }
2510
2511 static int del_balance_item(struct btrfs_root *root)
2512 {
2513 struct btrfs_trans_handle *trans;
2514 struct btrfs_path *path;
2515 struct btrfs_key key;
2516 int ret, err;
2517
2518 path = btrfs_alloc_path();
2519 if (!path)
2520 return -ENOMEM;
2521
2522 trans = btrfs_start_transaction(root, 0);
2523 if (IS_ERR(trans)) {
2524 btrfs_free_path(path);
2525 return PTR_ERR(trans);
2526 }
2527
2528 key.objectid = BTRFS_BALANCE_OBJECTID;
2529 key.type = BTRFS_BALANCE_ITEM_KEY;
2530 key.offset = 0;
2531
2532 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2533 if (ret < 0)
2534 goto out;
2535 if (ret > 0) {
2536 ret = -ENOENT;
2537 goto out;
2538 }
2539
2540 ret = btrfs_del_item(trans, root, path);
2541 out:
2542 btrfs_free_path(path);
2543 err = btrfs_commit_transaction(trans, root);
2544 if (err && !ret)
2545 ret = err;
2546 return ret;
2547 }
2548
2549 /*
2550 * This is a heuristic used to reduce the number of chunks balanced on
2551 * resume after balance was interrupted.
2552 */
2553 static void update_balance_args(struct btrfs_balance_control *bctl)
2554 {
2555 /*
2556 * Turn on soft mode for chunk types that were being converted.
2557 */
2558 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
2559 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
2560 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
2561 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
2562 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
2563 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
2564
2565 /*
2566 * Turn on usage filter if is not already used. The idea is
2567 * that chunks that we have already balanced should be
2568 * reasonably full. Don't do it for chunks that are being
2569 * converted - that will keep us from relocating unconverted
2570 * (albeit full) chunks.
2571 */
2572 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2573 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2574 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
2575 bctl->data.usage = 90;
2576 }
2577 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2578 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2579 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
2580 bctl->sys.usage = 90;
2581 }
2582 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2583 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2584 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
2585 bctl->meta.usage = 90;
2586 }
2587 }
2588
2589 /*
2590 * Should be called with both balance and volume mutexes held to
2591 * serialize other volume operations (add_dev/rm_dev/resize) with
2592 * restriper. Same goes for unset_balance_control.
2593 */
2594 static void set_balance_control(struct btrfs_balance_control *bctl)
2595 {
2596 struct btrfs_fs_info *fs_info = bctl->fs_info;
2597
2598 BUG_ON(fs_info->balance_ctl);
2599
2600 spin_lock(&fs_info->balance_lock);
2601 fs_info->balance_ctl = bctl;
2602 spin_unlock(&fs_info->balance_lock);
2603 }
2604
2605 static void unset_balance_control(struct btrfs_fs_info *fs_info)
2606 {
2607 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
2608
2609 BUG_ON(!fs_info->balance_ctl);
2610
2611 spin_lock(&fs_info->balance_lock);
2612 fs_info->balance_ctl = NULL;
2613 spin_unlock(&fs_info->balance_lock);
2614
2615 kfree(bctl);
2616 }
2617
2618 /*
2619 * Balance filters. Return 1 if chunk should be filtered out
2620 * (should not be balanced).
2621 */
2622 static int chunk_profiles_filter(u64 chunk_type,
2623 struct btrfs_balance_args *bargs)
2624 {
2625 chunk_type = chunk_to_extended(chunk_type) &
2626 BTRFS_EXTENDED_PROFILE_MASK;
2627
2628 if (bargs->profiles & chunk_type)
2629 return 0;
2630
2631 return 1;
2632 }
2633
2634 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
2635 struct btrfs_balance_args *bargs)
2636 {
2637 struct btrfs_block_group_cache *cache;
2638 u64 chunk_used, user_thresh;
2639 int ret = 1;
2640
2641 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2642 chunk_used = btrfs_block_group_used(&cache->item);
2643
2644 user_thresh = div_factor_fine(cache->key.offset, bargs->usage);
2645 if (chunk_used < user_thresh)
2646 ret = 0;
2647
2648 btrfs_put_block_group(cache);
2649 return ret;
2650 }
2651
2652 static int chunk_devid_filter(struct extent_buffer *leaf,
2653 struct btrfs_chunk *chunk,
2654 struct btrfs_balance_args *bargs)
2655 {
2656 struct btrfs_stripe *stripe;
2657 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2658 int i;
2659
2660 for (i = 0; i < num_stripes; i++) {
2661 stripe = btrfs_stripe_nr(chunk, i);
2662 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
2663 return 0;
2664 }
2665
2666 return 1;
2667 }
2668
2669 /* [pstart, pend) */
2670 static int chunk_drange_filter(struct extent_buffer *leaf,
2671 struct btrfs_chunk *chunk,
2672 u64 chunk_offset,
2673 struct btrfs_balance_args *bargs)
2674 {
2675 struct btrfs_stripe *stripe;
2676 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2677 u64 stripe_offset;
2678 u64 stripe_length;
2679 int factor;
2680 int i;
2681
2682 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
2683 return 0;
2684
2685 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
2686 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {
2687 factor = num_stripes / 2;
2688 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {
2689 factor = num_stripes - 1;
2690 } else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {
2691 factor = num_stripes - 2;
2692 } else {
2693 factor = num_stripes;
2694 }
2695
2696 for (i = 0; i < num_stripes; i++) {
2697 stripe = btrfs_stripe_nr(chunk, i);
2698 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
2699 continue;
2700
2701 stripe_offset = btrfs_stripe_offset(leaf, stripe);
2702 stripe_length = btrfs_chunk_length(leaf, chunk);
2703 do_div(stripe_length, factor);
2704
2705 if (stripe_offset < bargs->pend &&
2706 stripe_offset + stripe_length > bargs->pstart)
2707 return 0;
2708 }
2709
2710 return 1;
2711 }
2712
2713 /* [vstart, vend) */
2714 static int chunk_vrange_filter(struct extent_buffer *leaf,
2715 struct btrfs_chunk *chunk,
2716 u64 chunk_offset,
2717 struct btrfs_balance_args *bargs)
2718 {
2719 if (chunk_offset < bargs->vend &&
2720 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
2721 /* at least part of the chunk is inside this vrange */
2722 return 0;
2723
2724 return 1;
2725 }
2726
2727 static int chunk_soft_convert_filter(u64 chunk_type,
2728 struct btrfs_balance_args *bargs)
2729 {
2730 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
2731 return 0;
2732
2733 chunk_type = chunk_to_extended(chunk_type) &
2734 BTRFS_EXTENDED_PROFILE_MASK;
2735
2736 if (bargs->target == chunk_type)
2737 return 1;
2738
2739 return 0;
2740 }
2741
2742 static int should_balance_chunk(struct btrfs_root *root,
2743 struct extent_buffer *leaf,
2744 struct btrfs_chunk *chunk, u64 chunk_offset)
2745 {
2746 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
2747 struct btrfs_balance_args *bargs = NULL;
2748 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
2749
2750 /* type filter */
2751 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
2752 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
2753 return 0;
2754 }
2755
2756 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
2757 bargs = &bctl->data;
2758 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
2759 bargs = &bctl->sys;
2760 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
2761 bargs = &bctl->meta;
2762
2763 /* profiles filter */
2764 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
2765 chunk_profiles_filter(chunk_type, bargs)) {
2766 return 0;
2767 }
2768
2769 /* usage filter */
2770 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
2771 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
2772 return 0;
2773 }
2774
2775 /* devid filter */
2776 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
2777 chunk_devid_filter(leaf, chunk, bargs)) {
2778 return 0;
2779 }
2780
2781 /* drange filter, makes sense only with devid filter */
2782 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
2783 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
2784 return 0;
2785 }
2786
2787 /* vrange filter */
2788 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
2789 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
2790 return 0;
2791 }
2792
2793 /* soft profile changing mode */
2794 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
2795 chunk_soft_convert_filter(chunk_type, bargs)) {
2796 return 0;
2797 }
2798
2799 return 1;
2800 }
2801
2802 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
2803 {
2804 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
2805 struct btrfs_root *chunk_root = fs_info->chunk_root;
2806 struct btrfs_root *dev_root = fs_info->dev_root;
2807 struct list_head *devices;
2808 struct btrfs_device *device;
2809 u64 old_size;
2810 u64 size_to_free;
2811 struct btrfs_chunk *chunk;
2812 struct btrfs_path *path;
2813 struct btrfs_key key;
2814 struct btrfs_key found_key;
2815 struct btrfs_trans_handle *trans;
2816 struct extent_buffer *leaf;
2817 int slot;
2818 int ret;
2819 int enospc_errors = 0;
2820 bool counting = true;
2821
2822 /* step one make some room on all the devices */
2823 devices = &fs_info->fs_devices->devices;
2824 list_for_each_entry(device, devices, dev_list) {
2825 old_size = device->total_bytes;
2826 size_to_free = div_factor(old_size, 1);
2827 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
2828 if (!device->writeable ||
2829 device->total_bytes - device->bytes_used > size_to_free ||
2830 device->is_tgtdev_for_dev_replace)
2831 continue;
2832
2833 ret = btrfs_shrink_device(device, old_size - size_to_free);
2834 if (ret == -ENOSPC)
2835 break;
2836 BUG_ON(ret);
2837
2838 trans = btrfs_start_transaction(dev_root, 0);
2839 BUG_ON(IS_ERR(trans));
2840
2841 ret = btrfs_grow_device(trans, device, old_size);
2842 BUG_ON(ret);
2843
2844 btrfs_end_transaction(trans, dev_root);
2845 }
2846
2847 /* step two, relocate all the chunks */
2848 path = btrfs_alloc_path();
2849 if (!path) {
2850 ret = -ENOMEM;
2851 goto error;
2852 }
2853
2854 /* zero out stat counters */
2855 spin_lock(&fs_info->balance_lock);
2856 memset(&bctl->stat, 0, sizeof(bctl->stat));
2857 spin_unlock(&fs_info->balance_lock);
2858 again:
2859 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2860 key.offset = (u64)-1;
2861 key.type = BTRFS_CHUNK_ITEM_KEY;
2862
2863 while (1) {
2864 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
2865 atomic_read(&fs_info->balance_cancel_req)) {
2866 ret = -ECANCELED;
2867 goto error;
2868 }
2869
2870 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2871 if (ret < 0)
2872 goto error;
2873
2874 /*
2875 * this shouldn't happen, it means the last relocate
2876 * failed
2877 */
2878 if (ret == 0)
2879 BUG(); /* FIXME break ? */
2880
2881 ret = btrfs_previous_item(chunk_root, path, 0,
2882 BTRFS_CHUNK_ITEM_KEY);
2883 if (ret) {
2884 ret = 0;
2885 break;
2886 }
2887
2888 leaf = path->nodes[0];
2889 slot = path->slots[0];
2890 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2891
2892 if (found_key.objectid != key.objectid)
2893 break;
2894
2895 /* chunk zero is special */
2896 if (found_key.offset == 0)
2897 break;
2898
2899 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
2900
2901 if (!counting) {
2902 spin_lock(&fs_info->balance_lock);
2903 bctl->stat.considered++;
2904 spin_unlock(&fs_info->balance_lock);
2905 }
2906
2907 ret = should_balance_chunk(chunk_root, leaf, chunk,
2908 found_key.offset);
2909 btrfs_release_path(path);
2910 if (!ret)
2911 goto loop;
2912
2913 if (counting) {
2914 spin_lock(&fs_info->balance_lock);
2915 bctl->stat.expected++;
2916 spin_unlock(&fs_info->balance_lock);
2917 goto loop;
2918 }
2919
2920 ret = btrfs_relocate_chunk(chunk_root,
2921 chunk_root->root_key.objectid,
2922 found_key.objectid,
2923 found_key.offset);
2924 if (ret && ret != -ENOSPC)
2925 goto error;
2926 if (ret == -ENOSPC) {
2927 enospc_errors++;
2928 } else {
2929 spin_lock(&fs_info->balance_lock);
2930 bctl->stat.completed++;
2931 spin_unlock(&fs_info->balance_lock);
2932 }
2933 loop:
2934 key.offset = found_key.offset - 1;
2935 }
2936
2937 if (counting) {
2938 btrfs_release_path(path);
2939 counting = false;
2940 goto again;
2941 }
2942 error:
2943 btrfs_free_path(path);
2944 if (enospc_errors) {
2945 printk(KERN_INFO "btrfs: %d enospc errors during balance\n",
2946 enospc_errors);
2947 if (!ret)
2948 ret = -ENOSPC;
2949 }
2950
2951 return ret;
2952 }
2953
2954 /**
2955 * alloc_profile_is_valid - see if a given profile is valid and reduced
2956 * @flags: profile to validate
2957 * @extended: if true @flags is treated as an extended profile
2958 */
2959 static int alloc_profile_is_valid(u64 flags, int extended)
2960 {
2961 u64 mask = (extended ? BTRFS_EXTENDED_PROFILE_MASK :
2962 BTRFS_BLOCK_GROUP_PROFILE_MASK);
2963
2964 flags &= ~BTRFS_BLOCK_GROUP_TYPE_MASK;
2965
2966 /* 1) check that all other bits are zeroed */
2967 if (flags & ~mask)
2968 return 0;
2969
2970 /* 2) see if profile is reduced */
2971 if (flags == 0)
2972 return !extended; /* "0" is valid for usual profiles */
2973
2974 /* true if exactly one bit set */
2975 return (flags & (flags - 1)) == 0;
2976 }
2977
2978 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
2979 {
2980 /* cancel requested || normal exit path */
2981 return atomic_read(&fs_info->balance_cancel_req) ||
2982 (atomic_read(&fs_info->balance_pause_req) == 0 &&
2983 atomic_read(&fs_info->balance_cancel_req) == 0);
2984 }
2985
2986 static void __cancel_balance(struct btrfs_fs_info *fs_info)
2987 {
2988 int ret;
2989
2990 unset_balance_control(fs_info);
2991 ret = del_balance_item(fs_info->tree_root);
2992 BUG_ON(ret);
2993 }
2994
2995 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
2996 struct btrfs_ioctl_balance_args *bargs);
2997
2998 /*
2999 * Should be called with both balance and volume mutexes held
3000 */
3001 int btrfs_balance(struct btrfs_balance_control *bctl,
3002 struct btrfs_ioctl_balance_args *bargs)
3003 {
3004 struct btrfs_fs_info *fs_info = bctl->fs_info;
3005 u64 allowed;
3006 int mixed = 0;
3007 int ret;
3008 u64 num_devices;
3009 int cancel = 0;
3010
3011 if (btrfs_fs_closing(fs_info) ||
3012 atomic_read(&fs_info->balance_pause_req) ||
3013 atomic_read(&fs_info->balance_cancel_req)) {
3014 ret = -EINVAL;
3015 goto out;
3016 }
3017
3018 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
3019 if (allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
3020 mixed = 1;
3021
3022 /*
3023 * In case of mixed groups both data and meta should be picked,
3024 * and identical options should be given for both of them.
3025 */
3026 allowed = BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA;
3027 if (mixed && (bctl->flags & allowed)) {
3028 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
3029 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
3030 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
3031 printk(KERN_ERR "btrfs: with mixed groups data and "
3032 "metadata balance options must be the same\n");
3033 ret = -EINVAL;
3034 goto out;
3035 }
3036 }
3037
3038 num_devices = fs_info->fs_devices->num_devices;
3039 btrfs_dev_replace_lock(&fs_info->dev_replace);
3040 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
3041 BUG_ON(num_devices < 1);
3042 num_devices--;
3043 }
3044 btrfs_dev_replace_unlock(&fs_info->dev_replace);
3045 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
3046 if (num_devices == 1)
3047 allowed |= BTRFS_BLOCK_GROUP_DUP;
3048 else if (num_devices < 4)
3049 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
3050 else
3051 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
3052 BTRFS_BLOCK_GROUP_RAID10 |
3053 BTRFS_BLOCK_GROUP_RAID5 |
3054 BTRFS_BLOCK_GROUP_RAID6);
3055
3056 if ((bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3057 (!alloc_profile_is_valid(bctl->data.target, 1) ||
3058 (bctl->data.target & ~allowed))) {
3059 printk(KERN_ERR "btrfs: unable to start balance with target "
3060 "data profile %llu\n",
3061 (unsigned long long)bctl->data.target);
3062 ret = -EINVAL;
3063 goto out;
3064 }
3065 if ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3066 (!alloc_profile_is_valid(bctl->meta.target, 1) ||
3067 (bctl->meta.target & ~allowed))) {
3068 printk(KERN_ERR "btrfs: unable to start balance with target "
3069 "metadata profile %llu\n",
3070 (unsigned long long)bctl->meta.target);
3071 ret = -EINVAL;
3072 goto out;
3073 }
3074 if ((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3075 (!alloc_profile_is_valid(bctl->sys.target, 1) ||
3076 (bctl->sys.target & ~allowed))) {
3077 printk(KERN_ERR "btrfs: unable to start balance with target "
3078 "system profile %llu\n",
3079 (unsigned long long)bctl->sys.target);
3080 ret = -EINVAL;
3081 goto out;
3082 }
3083
3084 /* allow dup'ed data chunks only in mixed mode */
3085 if (!mixed && (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3086 (bctl->data.target & BTRFS_BLOCK_GROUP_DUP)) {
3087 printk(KERN_ERR "btrfs: dup for data is not allowed\n");
3088 ret = -EINVAL;
3089 goto out;
3090 }
3091
3092 /* allow to reduce meta or sys integrity only if force set */
3093 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
3094 BTRFS_BLOCK_GROUP_RAID10 |
3095 BTRFS_BLOCK_GROUP_RAID5 |
3096 BTRFS_BLOCK_GROUP_RAID6;
3097
3098 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3099 (fs_info->avail_system_alloc_bits & allowed) &&
3100 !(bctl->sys.target & allowed)) ||
3101 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
3102 (fs_info->avail_metadata_alloc_bits & allowed) &&
3103 !(bctl->meta.target & allowed))) {
3104 if (bctl->flags & BTRFS_BALANCE_FORCE) {
3105 printk(KERN_INFO "btrfs: force reducing metadata "
3106 "integrity\n");
3107 } else {
3108 printk(KERN_ERR "btrfs: balance will reduce metadata "
3109 "integrity, use force if you want this\n");
3110 ret = -EINVAL;
3111 goto out;
3112 }
3113 }
3114
3115 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3116 int num_tolerated_disk_barrier_failures;
3117 u64 target = bctl->sys.target;
3118
3119 num_tolerated_disk_barrier_failures =
3120 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3121 if (num_tolerated_disk_barrier_failures > 0 &&
3122 (target &
3123 (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID0 |
3124 BTRFS_AVAIL_ALLOC_BIT_SINGLE)))
3125 num_tolerated_disk_barrier_failures = 0;
3126 else if (num_tolerated_disk_barrier_failures > 1 &&
3127 (target &
3128 (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)))
3129 num_tolerated_disk_barrier_failures = 1;
3130
3131 fs_info->num_tolerated_disk_barrier_failures =
3132 num_tolerated_disk_barrier_failures;
3133 }
3134
3135 ret = insert_balance_item(fs_info->tree_root, bctl);
3136 if (ret && ret != -EEXIST)
3137 goto out;
3138
3139 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
3140 BUG_ON(ret == -EEXIST);
3141 set_balance_control(bctl);
3142 } else {
3143 BUG_ON(ret != -EEXIST);
3144 spin_lock(&fs_info->balance_lock);
3145 update_balance_args(bctl);
3146 spin_unlock(&fs_info->balance_lock);
3147 }
3148
3149 atomic_inc(&fs_info->balance_running);
3150 mutex_unlock(&fs_info->balance_mutex);
3151
3152 ret = __btrfs_balance(fs_info);
3153
3154 mutex_lock(&fs_info->balance_mutex);
3155 atomic_dec(&fs_info->balance_running);
3156
3157 if (bargs) {
3158 memset(bargs, 0, sizeof(*bargs));
3159 update_ioctl_balance_args(fs_info, 0, bargs);
3160 }
3161
3162 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
3163 balance_need_close(fs_info))
3164 cancel = 1;
3165
3166 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) {
3167 fs_info->num_tolerated_disk_barrier_failures =
3168 btrfs_calc_num_tolerated_disk_barrier_failures(fs_info);
3169 }
3170
3171 if (cancel)
3172 __cancel_balance(fs_info);
3173
3174 wake_up(&fs_info->balance_wait_q);
3175
3176 return ret;
3177 out:
3178 if (bctl->flags & BTRFS_BALANCE_RESUME)
3179 __cancel_balance(fs_info);
3180 else
3181 kfree(bctl);
3182 return ret;
3183 }
3184
3185 static int balance_kthread(void *data)
3186 {
3187 struct btrfs_fs_info *fs_info = data;
3188 int ret = 0;
3189
3190 mutex_lock(&fs_info->volume_mutex);
3191 mutex_lock(&fs_info->balance_mutex);
3192
3193 if (fs_info->balance_ctl) {
3194 printk(KERN_INFO "btrfs: continuing balance\n");
3195 ret = btrfs_balance(fs_info->balance_ctl, NULL);
3196 }
3197
3198 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3199 mutex_unlock(&fs_info->balance_mutex);
3200 mutex_unlock(&fs_info->volume_mutex);
3201
3202 return ret;
3203 }
3204
3205 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
3206 {
3207 struct task_struct *tsk;
3208
3209 spin_lock(&fs_info->balance_lock);
3210 if (!fs_info->balance_ctl) {
3211 spin_unlock(&fs_info->balance_lock);
3212 return 0;
3213 }
3214 spin_unlock(&fs_info->balance_lock);
3215
3216 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
3217 printk(KERN_INFO "btrfs: force skipping balance\n");
3218 return 0;
3219 }
3220
3221 WARN_ON(atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1));
3222 tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
3223 if (IS_ERR(tsk))
3224 return PTR_ERR(tsk);
3225
3226 return 0;
3227 }
3228
3229 int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
3230 {
3231 struct btrfs_balance_control *bctl;
3232 struct btrfs_balance_item *item;
3233 struct btrfs_disk_balance_args disk_bargs;
3234 struct btrfs_path *path;
3235 struct extent_buffer *leaf;
3236 struct btrfs_key key;
3237 int ret;
3238
3239 path = btrfs_alloc_path();
3240 if (!path)
3241 return -ENOMEM;
3242
3243 key.objectid = BTRFS_BALANCE_OBJECTID;
3244 key.type = BTRFS_BALANCE_ITEM_KEY;
3245 key.offset = 0;
3246
3247 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
3248 if (ret < 0)
3249 goto out;
3250 if (ret > 0) { /* ret = -ENOENT; */
3251 ret = 0;
3252 goto out;
3253 }
3254
3255 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3256 if (!bctl) {
3257 ret = -ENOMEM;
3258 goto out;
3259 }
3260
3261 leaf = path->nodes[0];
3262 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
3263
3264 bctl->fs_info = fs_info;
3265 bctl->flags = btrfs_balance_flags(leaf, item);
3266 bctl->flags |= BTRFS_BALANCE_RESUME;
3267
3268 btrfs_balance_data(leaf, item, &disk_bargs);
3269 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
3270 btrfs_balance_meta(leaf, item, &disk_bargs);
3271 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
3272 btrfs_balance_sys(leaf, item, &disk_bargs);
3273 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
3274
3275 mutex_lock(&fs_info->volume_mutex);
3276 mutex_lock(&fs_info->balance_mutex);
3277
3278 set_balance_control(bctl);
3279
3280 mutex_unlock(&fs_info->balance_mutex);
3281 mutex_unlock(&fs_info->volume_mutex);
3282 out:
3283 btrfs_free_path(path);
3284 return ret;
3285 }
3286
3287 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
3288 {
3289 int ret = 0;
3290
3291 mutex_lock(&fs_info->balance_mutex);
3292 if (!fs_info->balance_ctl) {
3293 mutex_unlock(&fs_info->balance_mutex);
3294 return -ENOTCONN;
3295 }
3296
3297 if (atomic_read(&fs_info->balance_running)) {
3298 atomic_inc(&fs_info->balance_pause_req);
3299 mutex_unlock(&fs_info->balance_mutex);
3300
3301 wait_event(fs_info->balance_wait_q,
3302 atomic_read(&fs_info->balance_running) == 0);
3303
3304 mutex_lock(&fs_info->balance_mutex);
3305 /* we are good with balance_ctl ripped off from under us */
3306 BUG_ON(atomic_read(&fs_info->balance_running));
3307 atomic_dec(&fs_info->balance_pause_req);
3308 } else {
3309 ret = -ENOTCONN;
3310 }
3311
3312 mutex_unlock(&fs_info->balance_mutex);
3313 return ret;
3314 }
3315
3316 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
3317 {
3318 mutex_lock(&fs_info->balance_mutex);
3319 if (!fs_info->balance_ctl) {
3320 mutex_unlock(&fs_info->balance_mutex);
3321 return -ENOTCONN;
3322 }
3323
3324 atomic_inc(&fs_info->balance_cancel_req);
3325 /*
3326 * if we are running just wait and return, balance item is
3327 * deleted in btrfs_balance in this case
3328 */
3329 if (atomic_read(&fs_info->balance_running)) {
3330 mutex_unlock(&fs_info->balance_mutex);
3331 wait_event(fs_info->balance_wait_q,
3332 atomic_read(&fs_info->balance_running) == 0);
3333 mutex_lock(&fs_info->balance_mutex);
3334 } else {
3335 /* __cancel_balance needs volume_mutex */
3336 mutex_unlock(&fs_info->balance_mutex);
3337 mutex_lock(&fs_info->volume_mutex);
3338 mutex_lock(&fs_info->balance_mutex);
3339
3340 if (fs_info->balance_ctl)
3341 __cancel_balance(fs_info);
3342
3343 mutex_unlock(&fs_info->volume_mutex);
3344 }
3345
3346 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
3347 atomic_dec(&fs_info->balance_cancel_req);
3348 mutex_unlock(&fs_info->balance_mutex);
3349 return 0;
3350 }
3351
3352 /*
3353 * shrinking a device means finding all of the device extents past
3354 * the new size, and then following the back refs to the chunks.
3355 * The chunk relocation code actually frees the device extent
3356 */
3357 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
3358 {
3359 struct btrfs_trans_handle *trans;
3360 struct btrfs_root *root = device->dev_root;
3361 struct btrfs_dev_extent *dev_extent = NULL;
3362 struct btrfs_path *path;
3363 u64 length;
3364 u64 chunk_tree;
3365 u64 chunk_objectid;
3366 u64 chunk_offset;
3367 int ret;
3368 int slot;
3369 int failed = 0;
3370 bool retried = false;
3371 struct extent_buffer *l;
3372 struct btrfs_key key;
3373 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3374 u64 old_total = btrfs_super_total_bytes(super_copy);
3375 u64 old_size = device->total_bytes;
3376 u64 diff = device->total_bytes - new_size;
3377
3378 if (device->is_tgtdev_for_dev_replace)
3379 return -EINVAL;
3380
3381 path = btrfs_alloc_path();
3382 if (!path)
3383 return -ENOMEM;
3384
3385 path->reada = 2;
3386
3387 lock_chunks(root);
3388
3389 device->total_bytes = new_size;
3390 if (device->writeable) {
3391 device->fs_devices->total_rw_bytes -= diff;
3392 spin_lock(&root->fs_info->free_chunk_lock);
3393 root->fs_info->free_chunk_space -= diff;
3394 spin_unlock(&root->fs_info->free_chunk_lock);
3395 }
3396 unlock_chunks(root);
3397
3398 again:
3399 key.objectid = device->devid;
3400 key.offset = (u64)-1;
3401 key.type = BTRFS_DEV_EXTENT_KEY;
3402
3403 do {
3404 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3405 if (ret < 0)
3406 goto done;
3407
3408 ret = btrfs_previous_item(root, path, 0, key.type);
3409 if (ret < 0)
3410 goto done;
3411 if (ret) {
3412 ret = 0;
3413 btrfs_release_path(path);
3414 break;
3415 }
3416
3417 l = path->nodes[0];
3418 slot = path->slots[0];
3419 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
3420
3421 if (key.objectid != device->devid) {
3422 btrfs_release_path(path);
3423 break;
3424 }
3425
3426 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
3427 length = btrfs_dev_extent_length(l, dev_extent);
3428
3429 if (key.offset + length <= new_size) {
3430 btrfs_release_path(path);
3431 break;
3432 }
3433
3434 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
3435 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
3436 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
3437 btrfs_release_path(path);
3438
3439 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
3440 chunk_offset);
3441 if (ret && ret != -ENOSPC)
3442 goto done;
3443 if (ret == -ENOSPC)
3444 failed++;
3445 } while (key.offset-- > 0);
3446
3447 if (failed && !retried) {
3448 failed = 0;
3449 retried = true;
3450 goto again;
3451 } else if (failed && retried) {
3452 ret = -ENOSPC;
3453 lock_chunks(root);
3454
3455 device->total_bytes = old_size;
3456 if (device->writeable)
3457 device->fs_devices->total_rw_bytes += diff;
3458 spin_lock(&root->fs_info->free_chunk_lock);
3459 root->fs_info->free_chunk_space += diff;
3460 spin_unlock(&root->fs_info->free_chunk_lock);
3461 unlock_chunks(root);
3462 goto done;
3463 }
3464
3465 /* Shrinking succeeded, else we would be at "done". */
3466 trans = btrfs_start_transaction(root, 0);
3467 if (IS_ERR(trans)) {
3468 ret = PTR_ERR(trans);
3469 goto done;
3470 }
3471
3472 lock_chunks(root);
3473
3474 device->disk_total_bytes = new_size;
3475 /* Now btrfs_update_device() will change the on-disk size. */
3476 ret = btrfs_update_device(trans, device);
3477 if (ret) {
3478 unlock_chunks(root);
3479 btrfs_end_transaction(trans, root);
3480 goto done;
3481 }
3482 WARN_ON(diff > old_total);
3483 btrfs_set_super_total_bytes(super_copy, old_total - diff);
3484 unlock_chunks(root);
3485 btrfs_end_transaction(trans, root);
3486 done:
3487 btrfs_free_path(path);
3488 return ret;
3489 }
3490
3491 static int btrfs_add_system_chunk(struct btrfs_root *root,
3492 struct btrfs_key *key,
3493 struct btrfs_chunk *chunk, int item_size)
3494 {
3495 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3496 struct btrfs_disk_key disk_key;
3497 u32 array_size;
3498 u8 *ptr;
3499
3500 array_size = btrfs_super_sys_array_size(super_copy);
3501 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
3502 return -EFBIG;
3503
3504 ptr = super_copy->sys_chunk_array + array_size;
3505 btrfs_cpu_key_to_disk(&disk_key, key);
3506 memcpy(ptr, &disk_key, sizeof(disk_key));
3507 ptr += sizeof(disk_key);
3508 memcpy(ptr, chunk, item_size);
3509 item_size += sizeof(disk_key);
3510 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
3511 return 0;
3512 }
3513
3514 /*
3515 * sort the devices in descending order by max_avail, total_avail
3516 */
3517 static int btrfs_cmp_device_info(const void *a, const void *b)
3518 {
3519 const struct btrfs_device_info *di_a = a;
3520 const struct btrfs_device_info *di_b = b;
3521
3522 if (di_a->max_avail > di_b->max_avail)
3523 return -1;
3524 if (di_a->max_avail < di_b->max_avail)
3525 return 1;
3526 if (di_a->total_avail > di_b->total_avail)
3527 return -1;
3528 if (di_a->total_avail < di_b->total_avail)
3529 return 1;
3530 return 0;
3531 }
3532
3533 struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = {
3534 /*
3535 * sub_stripes info for map,
3536 * dev_stripes -- stripes per dev, 2 for DUP, 1 other wise
3537 * devs_max -- max devices per stripe, 0 for unlimited
3538 * devs_min -- min devices per stripe
3539 * devs_increment -- ndevs must be a multiple of this
3540 * ncopies -- how many copies of the data we have
3541 */
3542 { 2, 1, 0, 4, 2, 2 /* raid10 */ },
3543 { 1, 1, 2, 2, 2, 2 /* raid1 */ },
3544 { 1, 2, 1, 1, 1, 2 /* dup */ },
3545 { 1, 1, 0, 2, 1, 1 /* raid0 */ },
3546 { 1, 1, 0, 1, 1, 1 /* single */ },
3547 { 1, 1, 0, 2, 1, 2 /* raid5 */ },
3548 { 1, 1, 0, 3, 1, 3 /* raid6 */ },
3549 };
3550
3551 static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
3552 {
3553 /* TODO allow them to set a preferred stripe size */
3554 return 64 * 1024;
3555 }
3556
3557 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
3558 {
3559 u64 features;
3560
3561 if (!(type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)))
3562 return;
3563
3564 features = btrfs_super_incompat_flags(info->super_copy);
3565 if (features & BTRFS_FEATURE_INCOMPAT_RAID56)
3566 return;
3567
3568 features |= BTRFS_FEATURE_INCOMPAT_RAID56;
3569 btrfs_set_super_incompat_flags(info->super_copy, features);
3570 printk(KERN_INFO "btrfs: setting RAID5/6 feature flag\n");
3571 }
3572
3573 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
3574 struct btrfs_root *extent_root,
3575 struct map_lookup **map_ret,
3576 u64 *num_bytes_out, u64 *stripe_size_out,
3577 u64 start, u64 type)
3578 {
3579 struct btrfs_fs_info *info = extent_root->fs_info;
3580 struct btrfs_fs_devices *fs_devices = info->fs_devices;
3581 struct list_head *cur;
3582 struct map_lookup *map = NULL;
3583 struct extent_map_tree *em_tree;
3584 struct extent_map *em;
3585 struct btrfs_device_info *devices_info = NULL;
3586 u64 total_avail;
3587 int num_stripes; /* total number of stripes to allocate */
3588 int data_stripes; /* number of stripes that count for
3589 block group size */
3590 int sub_stripes; /* sub_stripes info for map */
3591 int dev_stripes; /* stripes per dev */
3592 int devs_max; /* max devs to use */
3593 int devs_min; /* min devs needed */
3594 int devs_increment; /* ndevs has to be a multiple of this */
3595 int ncopies; /* how many copies to data has */
3596 int ret;
3597 u64 max_stripe_size;
3598 u64 max_chunk_size;
3599 u64 stripe_size;
3600 u64 num_bytes;
3601 u64 raid_stripe_len = BTRFS_STRIPE_LEN;
3602 int ndevs;
3603 int i;
3604 int j;
3605 int index;
3606
3607 BUG_ON(!alloc_profile_is_valid(type, 0));
3608
3609 if (list_empty(&fs_devices->alloc_list))
3610 return -ENOSPC;
3611
3612 index = __get_raid_index(type);
3613
3614 sub_stripes = btrfs_raid_array[index].sub_stripes;
3615 dev_stripes = btrfs_raid_array[index].dev_stripes;
3616 devs_max = btrfs_raid_array[index].devs_max;
3617 devs_min = btrfs_raid_array[index].devs_min;
3618 devs_increment = btrfs_raid_array[index].devs_increment;
3619 ncopies = btrfs_raid_array[index].ncopies;
3620
3621 if (type & BTRFS_BLOCK_GROUP_DATA) {
3622 max_stripe_size = 1024 * 1024 * 1024;
3623 max_chunk_size = 10 * max_stripe_size;
3624 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
3625 /* for larger filesystems, use larger metadata chunks */
3626 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
3627 max_stripe_size = 1024 * 1024 * 1024;
3628 else
3629 max_stripe_size = 256 * 1024 * 1024;
3630 max_chunk_size = max_stripe_size;
3631 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
3632 max_stripe_size = 32 * 1024 * 1024;
3633 max_chunk_size = 2 * max_stripe_size;
3634 } else {
3635 printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n",
3636 type);
3637 BUG_ON(1);
3638 }
3639
3640 /* we don't want a chunk larger than 10% of writeable space */
3641 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
3642 max_chunk_size);
3643
3644 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices,
3645 GFP_NOFS);
3646 if (!devices_info)
3647 return -ENOMEM;
3648
3649 cur = fs_devices->alloc_list.next;
3650
3651 /*
3652 * in the first pass through the devices list, we gather information
3653 * about the available holes on each device.
3654 */
3655 ndevs = 0;
3656 while (cur != &fs_devices->alloc_list) {
3657 struct btrfs_device *device;
3658 u64 max_avail;
3659 u64 dev_offset;
3660
3661 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
3662
3663 cur = cur->next;
3664
3665 if (!device->writeable) {
3666 WARN(1, KERN_ERR
3667 "btrfs: read-only device in alloc_list\n");
3668 continue;
3669 }
3670
3671 if (!device->in_fs_metadata ||
3672 device->is_tgtdev_for_dev_replace)
3673 continue;
3674
3675 if (device->total_bytes > device->bytes_used)
3676 total_avail = device->total_bytes - device->bytes_used;
3677 else
3678 total_avail = 0;
3679
3680 /* If there is no space on this device, skip it. */
3681 if (total_avail == 0)
3682 continue;
3683
3684 ret = find_free_dev_extent(device,
3685 max_stripe_size * dev_stripes,
3686 &dev_offset, &max_avail);
3687 if (ret && ret != -ENOSPC)
3688 goto error;
3689
3690 if (ret == 0)
3691 max_avail = max_stripe_size * dev_stripes;
3692
3693 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
3694 continue;
3695
3696 devices_info[ndevs].dev_offset = dev_offset;
3697 devices_info[ndevs].max_avail = max_avail;
3698 devices_info[ndevs].total_avail = total_avail;
3699 devices_info[ndevs].dev = device;
3700 ++ndevs;
3701 WARN_ON(ndevs > fs_devices->rw_devices);
3702 }
3703
3704 /*
3705 * now sort the devices by hole size / available space
3706 */
3707 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
3708 btrfs_cmp_device_info, NULL);
3709
3710 /* round down to number of usable stripes */
3711 ndevs -= ndevs % devs_increment;
3712
3713 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
3714 ret = -ENOSPC;
3715 goto error;
3716 }
3717
3718 if (devs_max && ndevs > devs_max)
3719 ndevs = devs_max;
3720 /*
3721 * the primary goal is to maximize the number of stripes, so use as many
3722 * devices as possible, even if the stripes are not maximum sized.
3723 */
3724 stripe_size = devices_info[ndevs-1].max_avail;
3725 num_stripes = ndevs * dev_stripes;
3726
3727 /*
3728 * this will have to be fixed for RAID1 and RAID10 over
3729 * more drives
3730 */
3731 data_stripes = num_stripes / ncopies;
3732
3733 if (stripe_size * ndevs > max_chunk_size * ncopies) {
3734 stripe_size = max_chunk_size * ncopies;
3735 do_div(stripe_size, ndevs);
3736 }
3737 if (type & BTRFS_BLOCK_GROUP_RAID5) {
3738 raid_stripe_len = find_raid56_stripe_len(ndevs - 1,
3739 btrfs_super_stripesize(info->super_copy));
3740 data_stripes = num_stripes - 1;
3741 }
3742 if (type & BTRFS_BLOCK_GROUP_RAID6) {
3743 raid_stripe_len = find_raid56_stripe_len(ndevs - 2,
3744 btrfs_super_stripesize(info->super_copy));
3745 data_stripes = num_stripes - 2;
3746 }
3747 do_div(stripe_size, dev_stripes);
3748
3749 /* align to BTRFS_STRIPE_LEN */
3750 do_div(stripe_size, raid_stripe_len);
3751 stripe_size *= raid_stripe_len;
3752
3753 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
3754 if (!map) {
3755 ret = -ENOMEM;
3756 goto error;
3757 }
3758 map->num_stripes = num_stripes;
3759
3760 for (i = 0; i < ndevs; ++i) {
3761 for (j = 0; j < dev_stripes; ++j) {
3762 int s = i * dev_stripes + j;
3763 map->stripes[s].dev = devices_info[i].dev;
3764 map->stripes[s].physical = devices_info[i].dev_offset +
3765 j * stripe_size;
3766 }
3767 }
3768 map->sector_size = extent_root->sectorsize;
3769 map->stripe_len = raid_stripe_len;
3770 map->io_align = raid_stripe_len;
3771 map->io_width = raid_stripe_len;
3772 map->type = type;
3773 map->sub_stripes = sub_stripes;
3774
3775 *map_ret = map;
3776 num_bytes = stripe_size * data_stripes;
3777
3778 *stripe_size_out = stripe_size;
3779 *num_bytes_out = num_bytes;
3780
3781 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
3782
3783 em = alloc_extent_map();
3784 if (!em) {
3785 ret = -ENOMEM;
3786 goto error;
3787 }
3788 em->bdev = (struct block_device *)map;
3789 em->start = start;
3790 em->len = num_bytes;
3791 em->block_start = 0;
3792 em->block_len = em->len;
3793
3794 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
3795 write_lock(&em_tree->lock);
3796 ret = add_extent_mapping(em_tree, em);
3797 write_unlock(&em_tree->lock);
3798 free_extent_map(em);
3799 if (ret)
3800 goto error;
3801
3802 ret = btrfs_make_block_group(trans, extent_root, 0, type,
3803 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
3804 start, num_bytes);
3805 if (ret)
3806 goto error;
3807
3808 for (i = 0; i < map->num_stripes; ++i) {
3809 struct btrfs_device *device;
3810 u64 dev_offset;
3811
3812 device = map->stripes[i].dev;
3813 dev_offset = map->stripes[i].physical;
3814
3815 ret = btrfs_alloc_dev_extent(trans, device,
3816 info->chunk_root->root_key.objectid,
3817 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
3818 start, dev_offset, stripe_size);
3819 if (ret) {
3820 btrfs_abort_transaction(trans, extent_root, ret);
3821 goto error;
3822 }
3823 }
3824
3825 check_raid56_incompat_flag(extent_root->fs_info, type);
3826
3827 kfree(devices_info);
3828 return 0;
3829
3830 error:
3831 kfree(map);
3832 kfree(devices_info);
3833 return ret;
3834 }
3835
3836 static int __finish_chunk_alloc(struct btrfs_trans_handle *trans,
3837 struct btrfs_root *extent_root,
3838 struct map_lookup *map, u64 chunk_offset,
3839 u64 chunk_size, u64 stripe_size)
3840 {
3841 u64 dev_offset;
3842 struct btrfs_key key;
3843 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
3844 struct btrfs_device *device;
3845 struct btrfs_chunk *chunk;
3846 struct btrfs_stripe *stripe;
3847 size_t item_size = btrfs_chunk_item_size(map->num_stripes);
3848 int index = 0;
3849 int ret;
3850
3851 chunk = kzalloc(item_size, GFP_NOFS);
3852 if (!chunk)
3853 return -ENOMEM;
3854
3855 index = 0;
3856 while (index < map->num_stripes) {
3857 device = map->stripes[index].dev;
3858 device->bytes_used += stripe_size;
3859 ret = btrfs_update_device(trans, device);
3860 if (ret)
3861 goto out_free;
3862 index++;
3863 }
3864
3865 spin_lock(&extent_root->fs_info->free_chunk_lock);
3866 extent_root->fs_info->free_chunk_space -= (stripe_size *
3867 map->num_stripes);
3868 spin_unlock(&extent_root->fs_info->free_chunk_lock);
3869
3870 index = 0;
3871 stripe = &chunk->stripe;
3872 while (index < map->num_stripes) {
3873 device = map->stripes[index].dev;
3874 dev_offset = map->stripes[index].physical;
3875
3876 btrfs_set_stack_stripe_devid(stripe, device->devid);
3877 btrfs_set_stack_stripe_offset(stripe, dev_offset);
3878 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
3879 stripe++;
3880 index++;
3881 }
3882
3883 btrfs_set_stack_chunk_length(chunk, chunk_size);
3884 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
3885 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
3886 btrfs_set_stack_chunk_type(chunk, map->type);
3887 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
3888 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
3889 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
3890 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
3891 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
3892
3893 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3894 key.type = BTRFS_CHUNK_ITEM_KEY;
3895 key.offset = chunk_offset;
3896
3897 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
3898
3899 if (ret == 0 && map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
3900 /*
3901 * TODO: Cleanup of inserted chunk root in case of
3902 * failure.
3903 */
3904 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
3905 item_size);
3906 }
3907
3908 out_free:
3909 kfree(chunk);
3910 return ret;
3911 }
3912
3913 /*
3914 * Chunk allocation falls into two parts. The first part does works
3915 * that make the new allocated chunk useable, but not do any operation
3916 * that modifies the chunk tree. The second part does the works that
3917 * require modifying the chunk tree. This division is important for the
3918 * bootstrap process of adding storage to a seed btrfs.
3919 */
3920 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
3921 struct btrfs_root *extent_root, u64 type)
3922 {
3923 u64 chunk_offset;
3924 u64 chunk_size;
3925 u64 stripe_size;
3926 struct map_lookup *map;
3927 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
3928 int ret;
3929
3930 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
3931 &chunk_offset);
3932 if (ret)
3933 return ret;
3934
3935 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
3936 &stripe_size, chunk_offset, type);
3937 if (ret)
3938 return ret;
3939
3940 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
3941 chunk_size, stripe_size);
3942 if (ret)
3943 return ret;
3944 return 0;
3945 }
3946
3947 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
3948 struct btrfs_root *root,
3949 struct btrfs_device *device)
3950 {
3951 u64 chunk_offset;
3952 u64 sys_chunk_offset;
3953 u64 chunk_size;
3954 u64 sys_chunk_size;
3955 u64 stripe_size;
3956 u64 sys_stripe_size;
3957 u64 alloc_profile;
3958 struct map_lookup *map;
3959 struct map_lookup *sys_map;
3960 struct btrfs_fs_info *fs_info = root->fs_info;
3961 struct btrfs_root *extent_root = fs_info->extent_root;
3962 int ret;
3963
3964 ret = find_next_chunk(fs_info->chunk_root,
3965 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset);
3966 if (ret)
3967 return ret;
3968
3969 alloc_profile = BTRFS_BLOCK_GROUP_METADATA |
3970 fs_info->avail_metadata_alloc_bits;
3971 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
3972
3973 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
3974 &stripe_size, chunk_offset, alloc_profile);
3975 if (ret)
3976 return ret;
3977
3978 sys_chunk_offset = chunk_offset + chunk_size;
3979
3980 alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM |
3981 fs_info->avail_system_alloc_bits;
3982 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
3983
3984 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map,
3985 &sys_chunk_size, &sys_stripe_size,
3986 sys_chunk_offset, alloc_profile);
3987 if (ret) {
3988 btrfs_abort_transaction(trans, root, ret);
3989 goto out;
3990 }
3991
3992 ret = btrfs_add_device(trans, fs_info->chunk_root, device);
3993 if (ret) {
3994 btrfs_abort_transaction(trans, root, ret);
3995 goto out;
3996 }
3997
3998 /*
3999 * Modifying chunk tree needs allocating new blocks from both
4000 * system block group and metadata block group. So we only can
4001 * do operations require modifying the chunk tree after both
4002 * block groups were created.
4003 */
4004 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
4005 chunk_size, stripe_size);
4006 if (ret) {
4007 btrfs_abort_transaction(trans, root, ret);
4008 goto out;
4009 }
4010
4011 ret = __finish_chunk_alloc(trans, extent_root, sys_map,
4012 sys_chunk_offset, sys_chunk_size,
4013 sys_stripe_size);
4014 if (ret)
4015 btrfs_abort_transaction(trans, root, ret);
4016
4017 out:
4018
4019 return ret;
4020 }
4021
4022 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
4023 {
4024 struct extent_map *em;
4025 struct map_lookup *map;
4026 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4027 int readonly = 0;
4028 int i;
4029
4030 read_lock(&map_tree->map_tree.lock);
4031 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
4032 read_unlock(&map_tree->map_tree.lock);
4033 if (!em)
4034 return 1;
4035
4036 if (btrfs_test_opt(root, DEGRADED)) {
4037 free_extent_map(em);
4038 return 0;
4039 }
4040
4041 map = (struct map_lookup *)em->bdev;
4042 for (i = 0; i < map->num_stripes; i++) {
4043 if (!map->stripes[i].dev->writeable) {
4044 readonly = 1;
4045 break;
4046 }
4047 }
4048 free_extent_map(em);
4049 return readonly;
4050 }
4051
4052 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
4053 {
4054 extent_map_tree_init(&tree->map_tree);
4055 }
4056
4057 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
4058 {
4059 struct extent_map *em;
4060
4061 while (1) {
4062 write_lock(&tree->map_tree.lock);
4063 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
4064 if (em)
4065 remove_extent_mapping(&tree->map_tree, em);
4066 write_unlock(&tree->map_tree.lock);
4067 if (!em)
4068 break;
4069 kfree(em->bdev);
4070 /* once for us */
4071 free_extent_map(em);
4072 /* once for the tree */
4073 free_extent_map(em);
4074 }
4075 }
4076
4077 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len)
4078 {
4079 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4080 struct extent_map *em;
4081 struct map_lookup *map;
4082 struct extent_map_tree *em_tree = &map_tree->map_tree;
4083 int ret;
4084
4085 read_lock(&em_tree->lock);
4086 em = lookup_extent_mapping(em_tree, logical, len);
4087 read_unlock(&em_tree->lock);
4088 BUG_ON(!em);
4089
4090 BUG_ON(em->start > logical || em->start + em->len < logical);
4091 map = (struct map_lookup *)em->bdev;
4092 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
4093 ret = map->num_stripes;
4094 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
4095 ret = map->sub_stripes;
4096 else if (map->type & BTRFS_BLOCK_GROUP_RAID5)
4097 ret = 2;
4098 else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
4099 ret = 3;
4100 else
4101 ret = 1;
4102 free_extent_map(em);
4103
4104 btrfs_dev_replace_lock(&fs_info->dev_replace);
4105 if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))
4106 ret++;
4107 btrfs_dev_replace_unlock(&fs_info->dev_replace);
4108
4109 return ret;
4110 }
4111
4112 unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
4113 struct btrfs_mapping_tree *map_tree,
4114 u64 logical)
4115 {
4116 struct extent_map *em;
4117 struct map_lookup *map;
4118 struct extent_map_tree *em_tree = &map_tree->map_tree;
4119 unsigned long len = root->sectorsize;
4120
4121 read_lock(&em_tree->lock);
4122 em = lookup_extent_mapping(em_tree, logical, len);
4123 read_unlock(&em_tree->lock);
4124 BUG_ON(!em);
4125
4126 BUG_ON(em->start > logical || em->start + em->len < logical);
4127 map = (struct map_lookup *)em->bdev;
4128 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
4129 BTRFS_BLOCK_GROUP_RAID6)) {
4130 len = map->stripe_len * nr_data_stripes(map);
4131 }
4132 free_extent_map(em);
4133 return len;
4134 }
4135
4136 int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
4137 u64 logical, u64 len, int mirror_num)
4138 {
4139 struct extent_map *em;
4140 struct map_lookup *map;
4141 struct extent_map_tree *em_tree = &map_tree->map_tree;
4142 int ret = 0;
4143
4144 read_lock(&em_tree->lock);
4145 em = lookup_extent_mapping(em_tree, logical, len);
4146 read_unlock(&em_tree->lock);
4147 BUG_ON(!em);
4148
4149 BUG_ON(em->start > logical || em->start + em->len < logical);
4150 map = (struct map_lookup *)em->bdev;
4151 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
4152 BTRFS_BLOCK_GROUP_RAID6))
4153 ret = 1;
4154 free_extent_map(em);
4155 return ret;
4156 }
4157
4158 static int find_live_mirror(struct btrfs_fs_info *fs_info,
4159 struct map_lookup *map, int first, int num,
4160 int optimal, int dev_replace_is_ongoing)
4161 {
4162 int i;
4163 int tolerance;
4164 struct btrfs_device *srcdev;
4165
4166 if (dev_replace_is_ongoing &&
4167 fs_info->dev_replace.cont_reading_from_srcdev_mode ==
4168 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID)
4169 srcdev = fs_info->dev_replace.srcdev;
4170 else
4171 srcdev = NULL;
4172
4173 /*
4174 * try to avoid the drive that is the source drive for a
4175 * dev-replace procedure, only choose it if no other non-missing
4176 * mirror is available
4177 */
4178 for (tolerance = 0; tolerance < 2; tolerance++) {
4179 if (map->stripes[optimal].dev->bdev &&
4180 (tolerance || map->stripes[optimal].dev != srcdev))
4181 return optimal;
4182 for (i = first; i < first + num; i++) {
4183 if (map->stripes[i].dev->bdev &&
4184 (tolerance || map->stripes[i].dev != srcdev))
4185 return i;
4186 }
4187 }
4188
4189 /* we couldn't find one that doesn't fail. Just return something
4190 * and the io error handling code will clean up eventually
4191 */
4192 return optimal;
4193 }
4194
4195 static inline int parity_smaller(u64 a, u64 b)
4196 {
4197 return a > b;
4198 }
4199
4200 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
4201 static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map)
4202 {
4203 struct btrfs_bio_stripe s;
4204 int i;
4205 u64 l;
4206 int again = 1;
4207
4208 while (again) {
4209 again = 0;
4210 for (i = 0; i < bbio->num_stripes - 1; i++) {
4211 if (parity_smaller(raid_map[i], raid_map[i+1])) {
4212 s = bbio->stripes[i];
4213 l = raid_map[i];
4214 bbio->stripes[i] = bbio->stripes[i+1];
4215 raid_map[i] = raid_map[i+1];
4216 bbio->stripes[i+1] = s;
4217 raid_map[i+1] = l;
4218 again = 1;
4219 }
4220 }
4221 }
4222 }
4223
4224 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
4225 u64 logical, u64 *length,
4226 struct btrfs_bio **bbio_ret,
4227 int mirror_num, u64 **raid_map_ret)
4228 {
4229 struct extent_map *em;
4230 struct map_lookup *map;
4231 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
4232 struct extent_map_tree *em_tree = &map_tree->map_tree;
4233 u64 offset;
4234 u64 stripe_offset;
4235 u64 stripe_end_offset;
4236 u64 stripe_nr;
4237 u64 stripe_nr_orig;
4238 u64 stripe_nr_end;
4239 u64 stripe_len;
4240 u64 *raid_map = NULL;
4241 int stripe_index;
4242 int i;
4243 int ret = 0;
4244 int num_stripes;
4245 int max_errors = 0;
4246 struct btrfs_bio *bbio = NULL;
4247 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
4248 int dev_replace_is_ongoing = 0;
4249 int num_alloc_stripes;
4250 int patch_the_first_stripe_for_dev_replace = 0;
4251 u64 physical_to_patch_in_first_stripe = 0;
4252 u64 raid56_full_stripe_start = (u64)-1;
4253
4254 read_lock(&em_tree->lock);
4255 em = lookup_extent_mapping(em_tree, logical, *length);
4256 read_unlock(&em_tree->lock);
4257
4258 if (!em) {
4259 printk(KERN_CRIT "btrfs: unable to find logical %llu len %llu\n",
4260 (unsigned long long)logical,
4261 (unsigned long long)*length);
4262 BUG();
4263 }
4264
4265 BUG_ON(em->start > logical || em->start + em->len < logical);
4266 map = (struct map_lookup *)em->bdev;
4267 offset = logical - em->start;
4268
4269 if (mirror_num > map->num_stripes)
4270 mirror_num = 0;
4271
4272 stripe_len = map->stripe_len;
4273 stripe_nr = offset;
4274 /*
4275 * stripe_nr counts the total number of stripes we have to stride
4276 * to get to this block
4277 */
4278 do_div(stripe_nr, stripe_len);
4279
4280 stripe_offset = stripe_nr * stripe_len;
4281 BUG_ON(offset < stripe_offset);
4282
4283 /* stripe_offset is the offset of this block in its stripe*/
4284 stripe_offset = offset - stripe_offset;
4285
4286 /* if we're here for raid56, we need to know the stripe aligned start */
4287 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) {
4288 unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
4289 raid56_full_stripe_start = offset;
4290
4291 /* allow a write of a full stripe, but make sure we don't
4292 * allow straddling of stripes
4293 */
4294 do_div(raid56_full_stripe_start, full_stripe_len);
4295 raid56_full_stripe_start *= full_stripe_len;
4296 }
4297
4298 if (rw & REQ_DISCARD) {
4299 /* we don't discard raid56 yet */
4300 if (map->type &
4301 (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) {
4302 ret = -EOPNOTSUPP;
4303 goto out;
4304 }
4305 *length = min_t(u64, em->len - offset, *length);
4306 } else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
4307 u64 max_len;
4308 /* For writes to RAID[56], allow a full stripeset across all disks.
4309 For other RAID types and for RAID[56] reads, just allow a single
4310 stripe (on a single disk). */
4311 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6) &&
4312 (rw & REQ_WRITE)) {
4313 max_len = stripe_len * nr_data_stripes(map) -
4314 (offset - raid56_full_stripe_start);
4315 } else {
4316 /* we limit the length of each bio to what fits in a stripe */
4317 max_len = stripe_len - stripe_offset;
4318 }
4319 *length = min_t(u64, em->len - offset, max_len);
4320 } else {
4321 *length = em->len - offset;
4322 }
4323
4324 /* This is for when we're called from btrfs_merge_bio_hook() and all
4325 it cares about is the length */
4326 if (!bbio_ret)
4327 goto out;
4328
4329 btrfs_dev_replace_lock(dev_replace);
4330 dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
4331 if (!dev_replace_is_ongoing)
4332 btrfs_dev_replace_unlock(dev_replace);
4333
4334 if (dev_replace_is_ongoing && mirror_num == map->num_stripes + 1 &&
4335 !(rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) &&
4336 dev_replace->tgtdev != NULL) {
4337 /*
4338 * in dev-replace case, for repair case (that's the only
4339 * case where the mirror is selected explicitly when
4340 * calling btrfs_map_block), blocks left of the left cursor
4341 * can also be read from the target drive.
4342 * For REQ_GET_READ_MIRRORS, the target drive is added as
4343 * the last one to the array of stripes. For READ, it also
4344 * needs to be supported using the same mirror number.
4345 * If the requested block is not left of the left cursor,
4346 * EIO is returned. This can happen because btrfs_num_copies()
4347 * returns one more in the dev-replace case.
4348 */
4349 u64 tmp_length = *length;
4350 struct btrfs_bio *tmp_bbio = NULL;
4351 int tmp_num_stripes;
4352 u64 srcdev_devid = dev_replace->srcdev->devid;
4353 int index_srcdev = 0;
4354 int found = 0;
4355 u64 physical_of_found = 0;
4356
4357 ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
4358 logical, &tmp_length, &tmp_bbio, 0, NULL);
4359 if (ret) {
4360 WARN_ON(tmp_bbio != NULL);
4361 goto out;
4362 }
4363
4364 tmp_num_stripes = tmp_bbio->num_stripes;
4365 if (mirror_num > tmp_num_stripes) {
4366 /*
4367 * REQ_GET_READ_MIRRORS does not contain this
4368 * mirror, that means that the requested area
4369 * is not left of the left cursor
4370 */
4371 ret = -EIO;
4372 kfree(tmp_bbio);
4373 goto out;
4374 }
4375
4376 /*
4377 * process the rest of the function using the mirror_num
4378 * of the source drive. Therefore look it up first.
4379 * At the end, patch the device pointer to the one of the
4380 * target drive.
4381 */
4382 for (i = 0; i < tmp_num_stripes; i++) {
4383 if (tmp_bbio->stripes[i].dev->devid == srcdev_devid) {
4384 /*
4385 * In case of DUP, in order to keep it
4386 * simple, only add the mirror with the
4387 * lowest physical address
4388 */
4389 if (found &&
4390 physical_of_found <=
4391 tmp_bbio->stripes[i].physical)
4392 continue;
4393 index_srcdev = i;
4394 found = 1;
4395 physical_of_found =
4396 tmp_bbio->stripes[i].physical;
4397 }
4398 }
4399
4400 if (found) {
4401 mirror_num = index_srcdev + 1;
4402 patch_the_first_stripe_for_dev_replace = 1;
4403 physical_to_patch_in_first_stripe = physical_of_found;
4404 } else {
4405 WARN_ON(1);
4406 ret = -EIO;
4407 kfree(tmp_bbio);
4408 goto out;
4409 }
4410
4411 kfree(tmp_bbio);
4412 } else if (mirror_num > map->num_stripes) {
4413 mirror_num = 0;
4414 }
4415
4416 num_stripes = 1;
4417 stripe_index = 0;
4418 stripe_nr_orig = stripe_nr;
4419 stripe_nr_end = (offset + *length + map->stripe_len - 1) &
4420 (~(map->stripe_len - 1));
4421 do_div(stripe_nr_end, map->stripe_len);
4422 stripe_end_offset = stripe_nr_end * map->stripe_len -
4423 (offset + *length);
4424
4425 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
4426 if (rw & REQ_DISCARD)
4427 num_stripes = min_t(u64, map->num_stripes,
4428 stripe_nr_end - stripe_nr_orig);
4429 stripe_index = do_div(stripe_nr, map->num_stripes);
4430 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
4431 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS))
4432 num_stripes = map->num_stripes;
4433 else if (mirror_num)
4434 stripe_index = mirror_num - 1;
4435 else {
4436 stripe_index = find_live_mirror(fs_info, map, 0,
4437 map->num_stripes,
4438 current->pid % map->num_stripes,
4439 dev_replace_is_ongoing);
4440 mirror_num = stripe_index + 1;
4441 }
4442
4443 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
4444 if (rw & (REQ_WRITE | REQ_DISCARD | REQ_GET_READ_MIRRORS)) {
4445 num_stripes = map->num_stripes;
4446 } else if (mirror_num) {
4447 stripe_index = mirror_num - 1;
4448 } else {
4449 mirror_num = 1;
4450 }
4451
4452 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
4453 int factor = map->num_stripes / map->sub_stripes;
4454
4455 stripe_index = do_div(stripe_nr, factor);
4456 stripe_index *= map->sub_stripes;
4457
4458 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
4459 num_stripes = map->sub_stripes;
4460 else if (rw & REQ_DISCARD)
4461 num_stripes = min_t(u64, map->sub_stripes *
4462 (stripe_nr_end - stripe_nr_orig),
4463 map->num_stripes);
4464 else if (mirror_num)
4465 stripe_index += mirror_num - 1;
4466 else {
4467 int old_stripe_index = stripe_index;
4468 stripe_index = find_live_mirror(fs_info, map,
4469 stripe_index,
4470 map->sub_stripes, stripe_index +
4471 current->pid % map->sub_stripes,
4472 dev_replace_is_ongoing);
4473 mirror_num = stripe_index - old_stripe_index + 1;
4474 }
4475
4476 } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
4477 BTRFS_BLOCK_GROUP_RAID6)) {
4478 u64 tmp;
4479
4480 if (bbio_ret && ((rw & REQ_WRITE) || mirror_num > 1)
4481 && raid_map_ret) {
4482 int i, rot;
4483
4484 /* push stripe_nr back to the start of the full stripe */
4485 stripe_nr = raid56_full_stripe_start;
4486 do_div(stripe_nr, stripe_len);
4487
4488 stripe_index = do_div(stripe_nr, nr_data_stripes(map));
4489
4490 /* RAID[56] write or recovery. Return all stripes */
4491 num_stripes = map->num_stripes;
4492 max_errors = nr_parity_stripes(map);
4493
4494 raid_map = kmalloc(sizeof(u64) * num_stripes,
4495 GFP_NOFS);
4496 if (!raid_map) {
4497 ret = -ENOMEM;
4498 goto out;
4499 }
4500
4501 /* Work out the disk rotation on this stripe-set */
4502 tmp = stripe_nr;
4503 rot = do_div(tmp, num_stripes);
4504
4505 /* Fill in the logical address of each stripe */
4506 tmp = stripe_nr * nr_data_stripes(map);
4507 for (i = 0; i < nr_data_stripes(map); i++)
4508 raid_map[(i+rot) % num_stripes] =
4509 em->start + (tmp + i) * map->stripe_len;
4510
4511 raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
4512 if (map->type & BTRFS_BLOCK_GROUP_RAID6)
4513 raid_map[(i+rot+1) % num_stripes] =
4514 RAID6_Q_STRIPE;
4515
4516 *length = map->stripe_len;
4517 stripe_index = 0;
4518 stripe_offset = 0;
4519 } else {
4520 /*
4521 * Mirror #0 or #1 means the original data block.
4522 * Mirror #2 is RAID5 parity block.
4523 * Mirror #3 is RAID6 Q block.
4524 */
4525 stripe_index = do_div(stripe_nr, nr_data_stripes(map));
4526 if (mirror_num > 1)
4527 stripe_index = nr_data_stripes(map) +
4528 mirror_num - 2;
4529
4530 /* We distribute the parity blocks across stripes */
4531 tmp = stripe_nr + stripe_index;
4532 stripe_index = do_div(tmp, map->num_stripes);
4533 }
4534 } else {
4535 /*
4536 * after this do_div call, stripe_nr is the number of stripes
4537 * on this device we have to walk to find the data, and
4538 * stripe_index is the number of our device in the stripe array
4539 */
4540 stripe_index = do_div(stripe_nr, map->num_stripes);
4541 mirror_num = stripe_index + 1;
4542 }
4543 BUG_ON(stripe_index >= map->num_stripes);
4544
4545 num_alloc_stripes = num_stripes;
4546 if (dev_replace_is_ongoing) {
4547 if (rw & (REQ_WRITE | REQ_DISCARD))
4548 num_alloc_stripes <<= 1;
4549 if (rw & REQ_GET_READ_MIRRORS)
4550 num_alloc_stripes++;
4551 }
4552 bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS);
4553 if (!bbio) {
4554 ret = -ENOMEM;
4555 goto out;
4556 }
4557 atomic_set(&bbio->error, 0);
4558
4559 if (rw & REQ_DISCARD) {
4560 int factor = 0;
4561 int sub_stripes = 0;
4562 u64 stripes_per_dev = 0;
4563 u32 remaining_stripes = 0;
4564 u32 last_stripe = 0;
4565
4566 if (map->type &
4567 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
4568 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
4569 sub_stripes = 1;
4570 else
4571 sub_stripes = map->sub_stripes;
4572
4573 factor = map->num_stripes / sub_stripes;
4574 stripes_per_dev = div_u64_rem(stripe_nr_end -
4575 stripe_nr_orig,
4576 factor,
4577 &remaining_stripes);
4578 div_u64_rem(stripe_nr_end - 1, factor, &last_stripe);
4579 last_stripe *= sub_stripes;
4580 }
4581
4582 for (i = 0; i < num_stripes; i++) {
4583 bbio->stripes[i].physical =
4584 map->stripes[stripe_index].physical +
4585 stripe_offset + stripe_nr * map->stripe_len;
4586 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
4587
4588 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
4589 BTRFS_BLOCK_GROUP_RAID10)) {
4590 bbio->stripes[i].length = stripes_per_dev *
4591 map->stripe_len;
4592
4593 if (i / sub_stripes < remaining_stripes)
4594 bbio->stripes[i].length +=
4595 map->stripe_len;
4596
4597 /*
4598 * Special for the first stripe and
4599 * the last stripe:
4600 *
4601 * |-------|...|-------|
4602 * |----------|
4603 * off end_off
4604 */
4605 if (i < sub_stripes)
4606 bbio->stripes[i].length -=
4607 stripe_offset;
4608
4609 if (stripe_index >= last_stripe &&
4610 stripe_index <= (last_stripe +
4611 sub_stripes - 1))
4612 bbio->stripes[i].length -=
4613 stripe_end_offset;
4614
4615 if (i == sub_stripes - 1)
4616 stripe_offset = 0;
4617 } else
4618 bbio->stripes[i].length = *length;
4619
4620 stripe_index++;
4621 if (stripe_index == map->num_stripes) {
4622 /* This could only happen for RAID0/10 */
4623 stripe_index = 0;
4624 stripe_nr++;
4625 }
4626 }
4627 } else {
4628 for (i = 0; i < num_stripes; i++) {
4629 bbio->stripes[i].physical =
4630 map->stripes[stripe_index].physical +
4631 stripe_offset +
4632 stripe_nr * map->stripe_len;
4633 bbio->stripes[i].dev =
4634 map->stripes[stripe_index].dev;
4635 stripe_index++;
4636 }
4637 }
4638
4639 if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) {
4640 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
4641 BTRFS_BLOCK_GROUP_RAID10 |
4642 BTRFS_BLOCK_GROUP_RAID5 |
4643 BTRFS_BLOCK_GROUP_DUP)) {
4644 max_errors = 1;
4645 } else if (map->type & BTRFS_BLOCK_GROUP_RAID6) {
4646 max_errors = 2;
4647 }
4648 }
4649
4650 if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
4651 dev_replace->tgtdev != NULL) {
4652 int index_where_to_add;
4653 u64 srcdev_devid = dev_replace->srcdev->devid;
4654
4655 /*
4656 * duplicate the write operations while the dev replace
4657 * procedure is running. Since the copying of the old disk
4658 * to the new disk takes place at run time while the
4659 * filesystem is mounted writable, the regular write
4660 * operations to the old disk have to be duplicated to go
4661 * to the new disk as well.
4662 * Note that device->missing is handled by the caller, and
4663 * that the write to the old disk is already set up in the
4664 * stripes array.
4665 */
4666 index_where_to_add = num_stripes;
4667 for (i = 0; i < num_stripes; i++) {
4668 if (bbio->stripes[i].dev->devid == srcdev_devid) {
4669 /* write to new disk, too */
4670 struct btrfs_bio_stripe *new =
4671 bbio->stripes + index_where_to_add;
4672 struct btrfs_bio_stripe *old =
4673 bbio->stripes + i;
4674
4675 new->physical = old->physical;
4676 new->length = old->length;
4677 new->dev = dev_replace->tgtdev;
4678 index_where_to_add++;
4679 max_errors++;
4680 }
4681 }
4682 num_stripes = index_where_to_add;
4683 } else if (dev_replace_is_ongoing && (rw & REQ_GET_READ_MIRRORS) &&
4684 dev_replace->tgtdev != NULL) {
4685 u64 srcdev_devid = dev_replace->srcdev->devid;
4686 int index_srcdev = 0;
4687 int found = 0;
4688 u64 physical_of_found = 0;
4689
4690 /*
4691 * During the dev-replace procedure, the target drive can
4692 * also be used to read data in case it is needed to repair
4693 * a corrupt block elsewhere. This is possible if the
4694 * requested area is left of the left cursor. In this area,
4695 * the target drive is a full copy of the source drive.
4696 */
4697 for (i = 0; i < num_stripes; i++) {
4698 if (bbio->stripes[i].dev->devid == srcdev_devid) {
4699 /*
4700 * In case of DUP, in order to keep it
4701 * simple, only add the mirror with the
4702 * lowest physical address
4703 */
4704 if (found &&
4705 physical_of_found <=
4706 bbio->stripes[i].physical)
4707 continue;
4708 index_srcdev = i;
4709 found = 1;
4710 physical_of_found = bbio->stripes[i].physical;
4711 }
4712 }
4713 if (found) {
4714 u64 length = map->stripe_len;
4715
4716 if (physical_of_found + length <=
4717 dev_replace->cursor_left) {
4718 struct btrfs_bio_stripe *tgtdev_stripe =
4719 bbio->stripes + num_stripes;
4720
4721 tgtdev_stripe->physical = physical_of_found;
4722 tgtdev_stripe->length =
4723 bbio->stripes[index_srcdev].length;
4724 tgtdev_stripe->dev = dev_replace->tgtdev;
4725
4726 num_stripes++;
4727 }
4728 }
4729 }
4730
4731 *bbio_ret = bbio;
4732 bbio->num_stripes = num_stripes;
4733 bbio->max_errors = max_errors;
4734 bbio->mirror_num = mirror_num;
4735
4736 /*
4737 * this is the case that REQ_READ && dev_replace_is_ongoing &&
4738 * mirror_num == num_stripes + 1 && dev_replace target drive is
4739 * available as a mirror
4740 */
4741 if (patch_the_first_stripe_for_dev_replace && num_stripes > 0) {
4742 WARN_ON(num_stripes > 1);
4743 bbio->stripes[0].dev = dev_replace->tgtdev;
4744 bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
4745 bbio->mirror_num = map->num_stripes + 1;
4746 }
4747 if (raid_map) {
4748 sort_parity_stripes(bbio, raid_map);
4749 *raid_map_ret = raid_map;
4750 }
4751 out:
4752 if (dev_replace_is_ongoing)
4753 btrfs_dev_replace_unlock(dev_replace);
4754 free_extent_map(em);
4755 return ret;
4756 }
4757
4758 int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
4759 u64 logical, u64 *length,
4760 struct btrfs_bio **bbio_ret, int mirror_num)
4761 {
4762 return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
4763 mirror_num, NULL);
4764 }
4765
4766 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
4767 u64 chunk_start, u64 physical, u64 devid,
4768 u64 **logical, int *naddrs, int *stripe_len)
4769 {
4770 struct extent_map_tree *em_tree = &map_tree->map_tree;
4771 struct extent_map *em;
4772 struct map_lookup *map;
4773 u64 *buf;
4774 u64 bytenr;
4775 u64 length;
4776 u64 stripe_nr;
4777 u64 rmap_len;
4778 int i, j, nr = 0;
4779
4780 read_lock(&em_tree->lock);
4781 em = lookup_extent_mapping(em_tree, chunk_start, 1);
4782 read_unlock(&em_tree->lock);
4783
4784 BUG_ON(!em || em->start != chunk_start);
4785 map = (struct map_lookup *)em->bdev;
4786
4787 length = em->len;
4788 rmap_len = map->stripe_len;
4789
4790 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
4791 do_div(length, map->num_stripes / map->sub_stripes);
4792 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
4793 do_div(length, map->num_stripes);
4794 else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
4795 BTRFS_BLOCK_GROUP_RAID6)) {
4796 do_div(length, nr_data_stripes(map));
4797 rmap_len = map->stripe_len * nr_data_stripes(map);
4798 }
4799
4800 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
4801 BUG_ON(!buf); /* -ENOMEM */
4802
4803 for (i = 0; i < map->num_stripes; i++) {
4804 if (devid && map->stripes[i].dev->devid != devid)
4805 continue;
4806 if (map->stripes[i].physical > physical ||
4807 map->stripes[i].physical + length <= physical)
4808 continue;
4809
4810 stripe_nr = physical - map->stripes[i].physical;
4811 do_div(stripe_nr, map->stripe_len);
4812
4813 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
4814 stripe_nr = stripe_nr * map->num_stripes + i;
4815 do_div(stripe_nr, map->sub_stripes);
4816 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
4817 stripe_nr = stripe_nr * map->num_stripes + i;
4818 } /* else if RAID[56], multiply by nr_data_stripes().
4819 * Alternatively, just use rmap_len below instead of
4820 * map->stripe_len */
4821
4822 bytenr = chunk_start + stripe_nr * rmap_len;
4823 WARN_ON(nr >= map->num_stripes);
4824 for (j = 0; j < nr; j++) {
4825 if (buf[j] == bytenr)
4826 break;
4827 }
4828 if (j == nr) {
4829 WARN_ON(nr >= map->num_stripes);
4830 buf[nr++] = bytenr;
4831 }
4832 }
4833
4834 *logical = buf;
4835 *naddrs = nr;
4836 *stripe_len = rmap_len;
4837
4838 free_extent_map(em);
4839 return 0;
4840 }
4841
4842 static void *merge_stripe_index_into_bio_private(void *bi_private,
4843 unsigned int stripe_index)
4844 {
4845 /*
4846 * with single, dup, RAID0, RAID1 and RAID10, stripe_index is
4847 * at most 1.
4848 * The alternative solution (instead of stealing bits from the
4849 * pointer) would be to allocate an intermediate structure
4850 * that contains the old private pointer plus the stripe_index.
4851 */
4852 BUG_ON((((uintptr_t)bi_private) & 3) != 0);
4853 BUG_ON(stripe_index > 3);
4854 return (void *)(((uintptr_t)bi_private) | stripe_index);
4855 }
4856
4857 static struct btrfs_bio *extract_bbio_from_bio_private(void *bi_private)
4858 {
4859 return (struct btrfs_bio *)(((uintptr_t)bi_private) & ~((uintptr_t)3));
4860 }
4861
4862 static unsigned int extract_stripe_index_from_bio_private(void *bi_private)
4863 {
4864 return (unsigned int)((uintptr_t)bi_private) & 3;
4865 }
4866
4867 static void btrfs_end_bio(struct bio *bio, int err)
4868 {
4869 struct btrfs_bio *bbio = extract_bbio_from_bio_private(bio->bi_private);
4870 int is_orig_bio = 0;
4871
4872 if (err) {
4873 atomic_inc(&bbio->error);
4874 if (err == -EIO || err == -EREMOTEIO) {
4875 unsigned int stripe_index =
4876 extract_stripe_index_from_bio_private(
4877 bio->bi_private);
4878 struct btrfs_device *dev;
4879
4880 BUG_ON(stripe_index >= bbio->num_stripes);
4881 dev = bbio->stripes[stripe_index].dev;
4882 if (dev->bdev) {
4883 if (bio->bi_rw & WRITE)
4884 btrfs_dev_stat_inc(dev,
4885 BTRFS_DEV_STAT_WRITE_ERRS);
4886 else
4887 btrfs_dev_stat_inc(dev,
4888 BTRFS_DEV_STAT_READ_ERRS);
4889 if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH)
4890 btrfs_dev_stat_inc(dev,
4891 BTRFS_DEV_STAT_FLUSH_ERRS);
4892 btrfs_dev_stat_print_on_error(dev);
4893 }
4894 }
4895 }
4896
4897 if (bio == bbio->orig_bio)
4898 is_orig_bio = 1;
4899
4900 if (atomic_dec_and_test(&bbio->stripes_pending)) {
4901 if (!is_orig_bio) {
4902 bio_put(bio);
4903 bio = bbio->orig_bio;
4904 }
4905 bio->bi_private = bbio->private;
4906 bio->bi_end_io = bbio->end_io;
4907 bio->bi_bdev = (struct block_device *)
4908 (unsigned long)bbio->mirror_num;
4909 /* only send an error to the higher layers if it is
4910 * beyond the tolerance of the btrfs bio
4911 */
4912 if (atomic_read(&bbio->error) > bbio->max_errors) {
4913 err = -EIO;
4914 } else {
4915 /*
4916 * this bio is actually up to date, we didn't
4917 * go over the max number of errors
4918 */
4919 set_bit(BIO_UPTODATE, &bio->bi_flags);
4920 err = 0;
4921 }
4922 kfree(bbio);
4923
4924 bio_endio(bio, err);
4925 } else if (!is_orig_bio) {
4926 bio_put(bio);
4927 }
4928 }
4929
4930 struct async_sched {
4931 struct bio *bio;
4932 int rw;
4933 struct btrfs_fs_info *info;
4934 struct btrfs_work work;
4935 };
4936
4937 /*
4938 * see run_scheduled_bios for a description of why bios are collected for
4939 * async submit.
4940 *
4941 * This will add one bio to the pending list for a device and make sure
4942 * the work struct is scheduled.
4943 */
4944 noinline void btrfs_schedule_bio(struct btrfs_root *root,
4945 struct btrfs_device *device,
4946 int rw, struct bio *bio)
4947 {
4948 int should_queue = 1;
4949 struct btrfs_pending_bios *pending_bios;
4950
4951 if (device->missing || !device->bdev) {
4952 bio_endio(bio, -EIO);
4953 return;
4954 }
4955
4956 /* don't bother with additional async steps for reads, right now */
4957 if (!(rw & REQ_WRITE)) {
4958 bio_get(bio);
4959 btrfsic_submit_bio(rw, bio);
4960 bio_put(bio);
4961 return;
4962 }
4963
4964 /*
4965 * nr_async_bios allows us to reliably return congestion to the
4966 * higher layers. Otherwise, the async bio makes it appear we have
4967 * made progress against dirty pages when we've really just put it
4968 * on a queue for later
4969 */
4970 atomic_inc(&root->fs_info->nr_async_bios);
4971 WARN_ON(bio->bi_next);
4972 bio->bi_next = NULL;
4973 bio->bi_rw |= rw;
4974
4975 spin_lock(&device->io_lock);
4976 if (bio->bi_rw & REQ_SYNC)
4977 pending_bios = &device->pending_sync_bios;
4978 else
4979 pending_bios = &device->pending_bios;
4980
4981 if (pending_bios->tail)
4982 pending_bios->tail->bi_next = bio;
4983
4984 pending_bios->tail = bio;
4985 if (!pending_bios->head)
4986 pending_bios->head = bio;
4987 if (device->running_pending)
4988 should_queue = 0;
4989
4990 spin_unlock(&device->io_lock);
4991
4992 if (should_queue)
4993 btrfs_queue_worker(&root->fs_info->submit_workers,
4994 &device->work);
4995 }
4996
4997 static int bio_size_ok(struct block_device *bdev, struct bio *bio,
4998 sector_t sector)
4999 {
5000 struct bio_vec *prev;
5001 struct request_queue *q = bdev_get_queue(bdev);
5002 unsigned short max_sectors = queue_max_sectors(q);
5003 struct bvec_merge_data bvm = {
5004 .bi_bdev = bdev,
5005 .bi_sector = sector,
5006 .bi_rw = bio->bi_rw,
5007 };
5008
5009 if (bio->bi_vcnt == 0) {
5010 WARN_ON(1);
5011 return 1;
5012 }
5013
5014 prev = &bio->bi_io_vec[bio->bi_vcnt - 1];
5015 if ((bio->bi_size >> 9) > max_sectors)
5016 return 0;
5017
5018 if (!q->merge_bvec_fn)
5019 return 1;
5020
5021 bvm.bi_size = bio->bi_size - prev->bv_len;
5022 if (q->merge_bvec_fn(q, &bvm, prev) < prev->bv_len)
5023 return 0;
5024 return 1;
5025 }
5026
5027 static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5028 struct bio *bio, u64 physical, int dev_nr,
5029 int rw, int async)
5030 {
5031 struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
5032
5033 bio->bi_private = bbio;
5034 bio->bi_private = merge_stripe_index_into_bio_private(
5035 bio->bi_private, (unsigned int)dev_nr);
5036 bio->bi_end_io = btrfs_end_bio;
5037 bio->bi_sector = physical >> 9;
5038 #ifdef DEBUG
5039 {
5040 struct rcu_string *name;
5041
5042 rcu_read_lock();
5043 name = rcu_dereference(dev->name);
5044 pr_debug("btrfs_map_bio: rw %d, sector=%llu, dev=%lu "
5045 "(%s id %llu), size=%u\n", rw,
5046 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev,
5047 name->str, dev->devid, bio->bi_size);
5048 rcu_read_unlock();
5049 }
5050 #endif
5051 bio->bi_bdev = dev->bdev;
5052 if (async)
5053 btrfs_schedule_bio(root, dev, rw, bio);
5054 else
5055 btrfsic_submit_bio(rw, bio);
5056 }
5057
5058 static int breakup_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
5059 struct bio *first_bio, struct btrfs_device *dev,
5060 int dev_nr, int rw, int async)
5061 {
5062 struct bio_vec *bvec = first_bio->bi_io_vec;
5063 struct bio *bio;
5064 int nr_vecs = bio_get_nr_vecs(dev->bdev);
5065 u64 physical = bbio->stripes[dev_nr].physical;
5066
5067 again:
5068 bio = btrfs_bio_alloc(dev->bdev, physical >> 9, nr_vecs, GFP_NOFS);
5069 if (!bio)
5070 return -ENOMEM;
5071
5072 while (bvec <= (first_bio->bi_io_vec + first_bio->bi_vcnt - 1)) {
5073 if (bio_add_page(bio, bvec->bv_page, bvec->bv_len,
5074 bvec->bv_offset) < bvec->bv_len) {
5075 u64 len = bio->bi_size;
5076
5077 atomic_inc(&bbio->stripes_pending);
5078 submit_stripe_bio(root, bbio, bio, physical, dev_nr,
5079 rw, async);
5080 physical += len;
5081 goto again;
5082 }
5083 bvec++;
5084 }
5085
5086 submit_stripe_bio(root, bbio, bio, physical, dev_nr, rw, async);
5087 return 0;
5088 }
5089
5090 static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
5091 {
5092 atomic_inc(&bbio->error);
5093 if (atomic_dec_and_test(&bbio->stripes_pending)) {
5094 bio->bi_private = bbio->private;
5095 bio->bi_end_io = bbio->end_io;
5096 bio->bi_bdev = (struct block_device *)
5097 (unsigned long)bbio->mirror_num;
5098 bio->bi_sector = logical >> 9;
5099 kfree(bbio);
5100 bio_endio(bio, -EIO);
5101 }
5102 }
5103
5104 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
5105 int mirror_num, int async_submit)
5106 {
5107 struct btrfs_device *dev;
5108 struct bio *first_bio = bio;
5109 u64 logical = (u64)bio->bi_sector << 9;
5110 u64 length = 0;
5111 u64 map_length;
5112 u64 *raid_map = NULL;
5113 int ret;
5114 int dev_nr = 0;
5115 int total_devs = 1;
5116 struct btrfs_bio *bbio = NULL;
5117
5118 length = bio->bi_size;
5119 map_length = length;
5120
5121 ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
5122 mirror_num, &raid_map);
5123 if (ret) /* -ENOMEM */
5124 return ret;
5125
5126 total_devs = bbio->num_stripes;
5127 bbio->orig_bio = first_bio;
5128 bbio->private = first_bio->bi_private;
5129 bbio->end_io = first_bio->bi_end_io;
5130 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
5131
5132 if (raid_map) {
5133 /* In this case, map_length has been set to the length of
5134 a single stripe; not the whole write */
5135 if (rw & WRITE) {
5136 return raid56_parity_write(root, bio, bbio,
5137 raid_map, map_length);
5138 } else {
5139 return raid56_parity_recover(root, bio, bbio,
5140 raid_map, map_length,
5141 mirror_num);
5142 }
5143 }
5144
5145 if (map_length < length) {
5146 printk(KERN_CRIT "btrfs: mapping failed logical %llu bio len %llu "
5147 "len %llu\n", (unsigned long long)logical,
5148 (unsigned long long)length,
5149 (unsigned long long)map_length);
5150 BUG();
5151 }
5152
5153 while (dev_nr < total_devs) {
5154 dev = bbio->stripes[dev_nr].dev;
5155 if (!dev || !dev->bdev || (rw & WRITE && !dev->writeable)) {
5156 bbio_error(bbio, first_bio, logical);
5157 dev_nr++;
5158 continue;
5159 }
5160
5161 /*
5162 * Check and see if we're ok with this bio based on it's size
5163 * and offset with the given device.
5164 */
5165 if (!bio_size_ok(dev->bdev, first_bio,
5166 bbio->stripes[dev_nr].physical >> 9)) {
5167 ret = breakup_stripe_bio(root, bbio, first_bio, dev,
5168 dev_nr, rw, async_submit);
5169 BUG_ON(ret);
5170 dev_nr++;
5171 continue;
5172 }
5173
5174 if (dev_nr < total_devs - 1) {
5175 bio = bio_clone(first_bio, GFP_NOFS);
5176 BUG_ON(!bio); /* -ENOMEM */
5177 } else {
5178 bio = first_bio;
5179 }
5180
5181 submit_stripe_bio(root, bbio, bio,
5182 bbio->stripes[dev_nr].physical, dev_nr, rw,
5183 async_submit);
5184 dev_nr++;
5185 }
5186 return 0;
5187 }
5188
5189 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid,
5190 u8 *uuid, u8 *fsid)
5191 {
5192 struct btrfs_device *device;
5193 struct btrfs_fs_devices *cur_devices;
5194
5195 cur_devices = fs_info->fs_devices;
5196 while (cur_devices) {
5197 if (!fsid ||
5198 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
5199 device = __find_device(&cur_devices->devices,
5200 devid, uuid);
5201 if (device)
5202 return device;
5203 }
5204 cur_devices = cur_devices->seed;
5205 }
5206 return NULL;
5207 }
5208
5209 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
5210 u64 devid, u8 *dev_uuid)
5211 {
5212 struct btrfs_device *device;
5213 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
5214
5215 device = kzalloc(sizeof(*device), GFP_NOFS);
5216 if (!device)
5217 return NULL;
5218 list_add(&device->dev_list,
5219 &fs_devices->devices);
5220 device->dev_root = root->fs_info->dev_root;
5221 device->devid = devid;
5222 device->work.func = pending_bios_fn;
5223 device->fs_devices = fs_devices;
5224 device->missing = 1;
5225 fs_devices->num_devices++;
5226 fs_devices->missing_devices++;
5227 spin_lock_init(&device->io_lock);
5228 INIT_LIST_HEAD(&device->dev_alloc_list);
5229 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE);
5230 return device;
5231 }
5232
5233 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
5234 struct extent_buffer *leaf,
5235 struct btrfs_chunk *chunk)
5236 {
5237 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
5238 struct map_lookup *map;
5239 struct extent_map *em;
5240 u64 logical;
5241 u64 length;
5242 u64 devid;
5243 u8 uuid[BTRFS_UUID_SIZE];
5244 int num_stripes;
5245 int ret;
5246 int i;
5247
5248 logical = key->offset;
5249 length = btrfs_chunk_length(leaf, chunk);
5250
5251 read_lock(&map_tree->map_tree.lock);
5252 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
5253 read_unlock(&map_tree->map_tree.lock);
5254
5255 /* already mapped? */
5256 if (em && em->start <= logical && em->start + em->len > logical) {
5257 free_extent_map(em);
5258 return 0;
5259 } else if (em) {
5260 free_extent_map(em);
5261 }
5262
5263 em = alloc_extent_map();
5264 if (!em)
5265 return -ENOMEM;
5266 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
5267 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
5268 if (!map) {
5269 free_extent_map(em);
5270 return -ENOMEM;
5271 }
5272
5273 em->bdev = (struct block_device *)map;
5274 em->start = logical;
5275 em->len = length;
5276 em->orig_start = 0;
5277 em->block_start = 0;
5278 em->block_len = em->len;
5279
5280 map->num_stripes = num_stripes;
5281 map->io_width = btrfs_chunk_io_width(leaf, chunk);
5282 map->io_align = btrfs_chunk_io_align(leaf, chunk);
5283 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
5284 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
5285 map->type = btrfs_chunk_type(leaf, chunk);
5286 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
5287 for (i = 0; i < num_stripes; i++) {
5288 map->stripes[i].physical =
5289 btrfs_stripe_offset_nr(leaf, chunk, i);
5290 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
5291 read_extent_buffer(leaf, uuid, (unsigned long)
5292 btrfs_stripe_dev_uuid_nr(chunk, i),
5293 BTRFS_UUID_SIZE);
5294 map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
5295 uuid, NULL);
5296 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
5297 kfree(map);
5298 free_extent_map(em);
5299 return -EIO;
5300 }
5301 if (!map->stripes[i].dev) {
5302 map->stripes[i].dev =
5303 add_missing_dev(root, devid, uuid);
5304 if (!map->stripes[i].dev) {
5305 kfree(map);
5306 free_extent_map(em);
5307 return -EIO;
5308 }
5309 }
5310 map->stripes[i].dev->in_fs_metadata = 1;
5311 }
5312
5313 write_lock(&map_tree->map_tree.lock);
5314 ret = add_extent_mapping(&map_tree->map_tree, em);
5315 write_unlock(&map_tree->map_tree.lock);
5316 BUG_ON(ret); /* Tree corruption */
5317 free_extent_map(em);
5318
5319 return 0;
5320 }
5321
5322 static void fill_device_from_item(struct extent_buffer *leaf,
5323 struct btrfs_dev_item *dev_item,
5324 struct btrfs_device *device)
5325 {
5326 unsigned long ptr;
5327
5328 device->devid = btrfs_device_id(leaf, dev_item);
5329 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
5330 device->total_bytes = device->disk_total_bytes;
5331 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
5332 device->type = btrfs_device_type(leaf, dev_item);
5333 device->io_align = btrfs_device_io_align(leaf, dev_item);
5334 device->io_width = btrfs_device_io_width(leaf, dev_item);
5335 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
5336 WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
5337 device->is_tgtdev_for_dev_replace = 0;
5338
5339 ptr = (unsigned long)btrfs_device_uuid(dev_item);
5340 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
5341 }
5342
5343 static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
5344 {
5345 struct btrfs_fs_devices *fs_devices;
5346 int ret;
5347
5348 BUG_ON(!mutex_is_locked(&uuid_mutex));
5349
5350 fs_devices = root->fs_info->fs_devices->seed;
5351 while (fs_devices) {
5352 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
5353 ret = 0;
5354 goto out;
5355 }
5356 fs_devices = fs_devices->seed;
5357 }
5358
5359 fs_devices = find_fsid(fsid);
5360 if (!fs_devices) {
5361 ret = -ENOENT;
5362 goto out;
5363 }
5364
5365 fs_devices = clone_fs_devices(fs_devices);
5366 if (IS_ERR(fs_devices)) {
5367 ret = PTR_ERR(fs_devices);
5368 goto out;
5369 }
5370
5371 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
5372 root->fs_info->bdev_holder);
5373 if (ret) {
5374 free_fs_devices(fs_devices);
5375 goto out;
5376 }
5377
5378 if (!fs_devices->seeding) {
5379 __btrfs_close_devices(fs_devices);
5380 free_fs_devices(fs_devices);
5381 ret = -EINVAL;
5382 goto out;
5383 }
5384
5385 fs_devices->seed = root->fs_info->fs_devices->seed;
5386 root->fs_info->fs_devices->seed = fs_devices;
5387 out:
5388 return ret;
5389 }
5390
5391 static int read_one_dev(struct btrfs_root *root,
5392 struct extent_buffer *leaf,
5393 struct btrfs_dev_item *dev_item)
5394 {
5395 struct btrfs_device *device;
5396 u64 devid;
5397 int ret;
5398 u8 fs_uuid[BTRFS_UUID_SIZE];
5399 u8 dev_uuid[BTRFS_UUID_SIZE];
5400
5401 devid = btrfs_device_id(leaf, dev_item);
5402 read_extent_buffer(leaf, dev_uuid,
5403 (unsigned long)btrfs_device_uuid(dev_item),
5404 BTRFS_UUID_SIZE);
5405 read_extent_buffer(leaf, fs_uuid,
5406 (unsigned long)btrfs_device_fsid(dev_item),
5407 BTRFS_UUID_SIZE);
5408
5409 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
5410 ret = open_seed_devices(root, fs_uuid);
5411 if (ret && !btrfs_test_opt(root, DEGRADED))
5412 return ret;
5413 }
5414
5415 device = btrfs_find_device(root->fs_info, devid, dev_uuid, fs_uuid);
5416 if (!device || !device->bdev) {
5417 if (!btrfs_test_opt(root, DEGRADED))
5418 return -EIO;
5419
5420 if (!device) {
5421 printk(KERN_WARNING "warning devid %llu missing\n",
5422 (unsigned long long)devid);
5423 device = add_missing_dev(root, devid, dev_uuid);
5424 if (!device)
5425 return -ENOMEM;
5426 } else if (!device->missing) {
5427 /*
5428 * this happens when a device that was properly setup
5429 * in the device info lists suddenly goes bad.
5430 * device->bdev is NULL, and so we have to set
5431 * device->missing to one here
5432 */
5433 root->fs_info->fs_devices->missing_devices++;
5434 device->missing = 1;
5435 }
5436 }
5437
5438 if (device->fs_devices != root->fs_info->fs_devices) {
5439 BUG_ON(device->writeable);
5440 if (device->generation !=
5441 btrfs_device_generation(leaf, dev_item))
5442 return -EINVAL;
5443 }
5444
5445 fill_device_from_item(leaf, dev_item, device);
5446 device->dev_root = root->fs_info->dev_root;
5447 device->in_fs_metadata = 1;
5448 if (device->writeable && !device->is_tgtdev_for_dev_replace) {
5449 device->fs_devices->total_rw_bytes += device->total_bytes;
5450 spin_lock(&root->fs_info->free_chunk_lock);
5451 root->fs_info->free_chunk_space += device->total_bytes -
5452 device->bytes_used;
5453 spin_unlock(&root->fs_info->free_chunk_lock);
5454 }
5455 ret = 0;
5456 return ret;
5457 }
5458
5459 int btrfs_read_sys_array(struct btrfs_root *root)
5460 {
5461 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
5462 struct extent_buffer *sb;
5463 struct btrfs_disk_key *disk_key;
5464 struct btrfs_chunk *chunk;
5465 u8 *ptr;
5466 unsigned long sb_ptr;
5467 int ret = 0;
5468 u32 num_stripes;
5469 u32 array_size;
5470 u32 len = 0;
5471 u32 cur;
5472 struct btrfs_key key;
5473
5474 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
5475 BTRFS_SUPER_INFO_SIZE);
5476 if (!sb)
5477 return -ENOMEM;
5478 btrfs_set_buffer_uptodate(sb);
5479 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
5480 /*
5481 * The sb extent buffer is artifical and just used to read the system array.
5482 * btrfs_set_buffer_uptodate() call does not properly mark all it's
5483 * pages up-to-date when the page is larger: extent does not cover the
5484 * whole page and consequently check_page_uptodate does not find all
5485 * the page's extents up-to-date (the hole beyond sb),
5486 * write_extent_buffer then triggers a WARN_ON.
5487 *
5488 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
5489 * but sb spans only this function. Add an explicit SetPageUptodate call
5490 * to silence the warning eg. on PowerPC 64.
5491 */
5492 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
5493 SetPageUptodate(sb->pages[0]);
5494
5495 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
5496 array_size = btrfs_super_sys_array_size(super_copy);
5497
5498 ptr = super_copy->sys_chunk_array;
5499 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
5500 cur = 0;
5501
5502 while (cur < array_size) {
5503 disk_key = (struct btrfs_disk_key *)ptr;
5504 btrfs_disk_key_to_cpu(&key, disk_key);
5505
5506 len = sizeof(*disk_key); ptr += len;
5507 sb_ptr += len;
5508 cur += len;
5509
5510 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
5511 chunk = (struct btrfs_chunk *)sb_ptr;
5512 ret = read_one_chunk(root, &key, sb, chunk);
5513 if (ret)
5514 break;
5515 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
5516 len = btrfs_chunk_item_size(num_stripes);
5517 } else {
5518 ret = -EIO;
5519 break;
5520 }
5521 ptr += len;
5522 sb_ptr += len;
5523 cur += len;
5524 }
5525 free_extent_buffer(sb);
5526 return ret;
5527 }
5528
5529 int btrfs_read_chunk_tree(struct btrfs_root *root)
5530 {
5531 struct btrfs_path *path;
5532 struct extent_buffer *leaf;
5533 struct btrfs_key key;
5534 struct btrfs_key found_key;
5535 int ret;
5536 int slot;
5537
5538 root = root->fs_info->chunk_root;
5539
5540 path = btrfs_alloc_path();
5541 if (!path)
5542 return -ENOMEM;
5543
5544 mutex_lock(&uuid_mutex);
5545 lock_chunks(root);
5546
5547 /* first we search for all of the device items, and then we
5548 * read in all of the chunk items. This way we can create chunk
5549 * mappings that reference all of the devices that are afound
5550 */
5551 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
5552 key.offset = 0;
5553 key.type = 0;
5554 again:
5555 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
5556 if (ret < 0)
5557 goto error;
5558 while (1) {
5559 leaf = path->nodes[0];
5560 slot = path->slots[0];
5561 if (slot >= btrfs_header_nritems(leaf)) {
5562 ret = btrfs_next_leaf(root, path);
5563 if (ret == 0)
5564 continue;
5565 if (ret < 0)
5566 goto error;
5567 break;
5568 }
5569 btrfs_item_key_to_cpu(leaf, &found_key, slot);
5570 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
5571 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
5572 break;
5573 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
5574 struct btrfs_dev_item *dev_item;
5575 dev_item = btrfs_item_ptr(leaf, slot,
5576 struct btrfs_dev_item);
5577 ret = read_one_dev(root, leaf, dev_item);
5578 if (ret)
5579 goto error;
5580 }
5581 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
5582 struct btrfs_chunk *chunk;
5583 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
5584 ret = read_one_chunk(root, &found_key, leaf, chunk);
5585 if (ret)
5586 goto error;
5587 }
5588 path->slots[0]++;
5589 }
5590 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
5591 key.objectid = 0;
5592 btrfs_release_path(path);
5593 goto again;
5594 }
5595 ret = 0;
5596 error:
5597 unlock_chunks(root);
5598 mutex_unlock(&uuid_mutex);
5599
5600 btrfs_free_path(path);
5601 return ret;
5602 }
5603
5604 static void __btrfs_reset_dev_stats(struct btrfs_device *dev)
5605 {
5606 int i;
5607
5608 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
5609 btrfs_dev_stat_reset(dev, i);
5610 }
5611
5612 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
5613 {
5614 struct btrfs_key key;
5615 struct btrfs_key found_key;
5616 struct btrfs_root *dev_root = fs_info->dev_root;
5617 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
5618 struct extent_buffer *eb;
5619 int slot;
5620 int ret = 0;
5621 struct btrfs_device *device;
5622 struct btrfs_path *path = NULL;
5623 int i;
5624
5625 path = btrfs_alloc_path();
5626 if (!path) {
5627 ret = -ENOMEM;
5628 goto out;
5629 }
5630
5631 mutex_lock(&fs_devices->device_list_mutex);
5632 list_for_each_entry(device, &fs_devices->devices, dev_list) {
5633 int item_size;
5634 struct btrfs_dev_stats_item *ptr;
5635
5636 key.objectid = 0;
5637 key.type = BTRFS_DEV_STATS_KEY;
5638 key.offset = device->devid;
5639 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
5640 if (ret) {
5641 __btrfs_reset_dev_stats(device);
5642 device->dev_stats_valid = 1;
5643 btrfs_release_path(path);
5644 continue;
5645 }
5646 slot = path->slots[0];
5647 eb = path->nodes[0];
5648 btrfs_item_key_to_cpu(eb, &found_key, slot);
5649 item_size = btrfs_item_size_nr(eb, slot);
5650
5651 ptr = btrfs_item_ptr(eb, slot,
5652 struct btrfs_dev_stats_item);
5653
5654 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
5655 if (item_size >= (1 + i) * sizeof(__le64))
5656 btrfs_dev_stat_set(device, i,
5657 btrfs_dev_stats_value(eb, ptr, i));
5658 else
5659 btrfs_dev_stat_reset(device, i);
5660 }
5661
5662 device->dev_stats_valid = 1;
5663 btrfs_dev_stat_print_on_load(device);
5664 btrfs_release_path(path);
5665 }
5666 mutex_unlock(&fs_devices->device_list_mutex);
5667
5668 out:
5669 btrfs_free_path(path);
5670 return ret < 0 ? ret : 0;
5671 }
5672
5673 static int update_dev_stat_item(struct btrfs_trans_handle *trans,
5674 struct btrfs_root *dev_root,
5675 struct btrfs_device *device)
5676 {
5677 struct btrfs_path *path;
5678 struct btrfs_key key;
5679 struct extent_buffer *eb;
5680 struct btrfs_dev_stats_item *ptr;
5681 int ret;
5682 int i;
5683
5684 key.objectid = 0;
5685 key.type = BTRFS_DEV_STATS_KEY;
5686 key.offset = device->devid;
5687
5688 path = btrfs_alloc_path();
5689 BUG_ON(!path);
5690 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
5691 if (ret < 0) {
5692 printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n",
5693 ret, rcu_str_deref(device->name));
5694 goto out;
5695 }
5696
5697 if (ret == 0 &&
5698 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
5699 /* need to delete old one and insert a new one */
5700 ret = btrfs_del_item(trans, dev_root, path);
5701 if (ret != 0) {
5702 printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n",
5703 rcu_str_deref(device->name), ret);
5704 goto out;
5705 }
5706 ret = 1;
5707 }
5708
5709 if (ret == 1) {
5710 /* need to insert a new item */
5711 btrfs_release_path(path);
5712 ret = btrfs_insert_empty_item(trans, dev_root, path,
5713 &key, sizeof(*ptr));
5714 if (ret < 0) {
5715 printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n",
5716 rcu_str_deref(device->name), ret);
5717 goto out;
5718 }
5719 }
5720
5721 eb = path->nodes[0];
5722 ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item);
5723 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
5724 btrfs_set_dev_stats_value(eb, ptr, i,
5725 btrfs_dev_stat_read(device, i));
5726 btrfs_mark_buffer_dirty(eb);
5727
5728 out:
5729 btrfs_free_path(path);
5730 return ret;
5731 }
5732
5733 /*
5734 * called from commit_transaction. Writes all changed device stats to disk.
5735 */
5736 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans,
5737 struct btrfs_fs_info *fs_info)
5738 {
5739 struct btrfs_root *dev_root = fs_info->dev_root;
5740 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
5741 struct btrfs_device *device;
5742 int ret = 0;
5743
5744 mutex_lock(&fs_devices->device_list_mutex);
5745 list_for_each_entry(device, &fs_devices->devices, dev_list) {
5746 if (!device->dev_stats_valid || !device->dev_stats_dirty)
5747 continue;
5748
5749 ret = update_dev_stat_item(trans, dev_root, device);
5750 if (!ret)
5751 device->dev_stats_dirty = 0;
5752 }
5753 mutex_unlock(&fs_devices->device_list_mutex);
5754
5755 return ret;
5756 }
5757
5758 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index)
5759 {
5760 btrfs_dev_stat_inc(dev, index);
5761 btrfs_dev_stat_print_on_error(dev);
5762 }
5763
5764 void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
5765 {
5766 if (!dev->dev_stats_valid)
5767 return;
5768 printk_ratelimited_in_rcu(KERN_ERR
5769 "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
5770 rcu_str_deref(dev->name),
5771 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
5772 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
5773 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
5774 btrfs_dev_stat_read(dev,
5775 BTRFS_DEV_STAT_CORRUPTION_ERRS),
5776 btrfs_dev_stat_read(dev,
5777 BTRFS_DEV_STAT_GENERATION_ERRS));
5778 }
5779
5780 static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
5781 {
5782 int i;
5783
5784 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
5785 if (btrfs_dev_stat_read(dev, i) != 0)
5786 break;
5787 if (i == BTRFS_DEV_STAT_VALUES_MAX)
5788 return; /* all values == 0, suppress message */
5789
5790 printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
5791 rcu_str_deref(dev->name),
5792 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
5793 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
5794 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
5795 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS),
5796 btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS));
5797 }
5798
5799 int btrfs_get_dev_stats(struct btrfs_root *root,
5800 struct btrfs_ioctl_get_dev_stats *stats)
5801 {
5802 struct btrfs_device *dev;
5803 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
5804 int i;
5805
5806 mutex_lock(&fs_devices->device_list_mutex);
5807 dev = btrfs_find_device(root->fs_info, stats->devid, NULL, NULL);
5808 mutex_unlock(&fs_devices->device_list_mutex);
5809
5810 if (!dev) {
5811 printk(KERN_WARNING
5812 "btrfs: get dev_stats failed, device not found\n");
5813 return -ENODEV;
5814 } else if (!dev->dev_stats_valid) {
5815 printk(KERN_WARNING
5816 "btrfs: get dev_stats failed, not yet valid\n");
5817 return -ENODEV;
5818 } else if (stats->flags & BTRFS_DEV_STATS_RESET) {
5819 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) {
5820 if (stats->nr_items > i)
5821 stats->values[i] =
5822 btrfs_dev_stat_read_and_reset(dev, i);
5823 else
5824 btrfs_dev_stat_reset(dev, i);
5825 }
5826 } else {
5827 for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++)
5828 if (stats->nr_items > i)
5829 stats->values[i] = btrfs_dev_stat_read(dev, i);
5830 }
5831 if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX)
5832 stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX;
5833 return 0;
5834 }
5835
5836 int btrfs_scratch_superblock(struct btrfs_device *device)
5837 {
5838 struct buffer_head *bh;
5839 struct btrfs_super_block *disk_super;
5840
5841 bh = btrfs_read_dev_super(device->bdev);
5842 if (!bh)
5843 return -EINVAL;
5844 disk_super = (struct btrfs_super_block *)bh->b_data;
5845
5846 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
5847 set_buffer_dirty(bh);
5848 sync_dirty_buffer(bh);
5849 brelse(bh);
5850
5851 return 0;
5852 }
Linux kernel - Deliverables
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