2 * Copyright (C) 2007 Oracle. All rights reserved.
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.
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.
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.
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 <asm/div64.h>
28 #include "extent_map.h"
30 #include "transaction.h"
31 #include "print-tree.h"
33 #include "async-thread.h"
43 struct btrfs_bio_stripe stripes
[];
46 static int init_first_rw_device(struct btrfs_trans_handle
*trans
,
47 struct btrfs_root
*root
,
48 struct btrfs_device
*device
);
49 static int btrfs_relocate_sys_chunks(struct btrfs_root
*root
);
51 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
52 (sizeof(struct btrfs_bio_stripe) * (n)))
54 static DEFINE_MUTEX(uuid_mutex
);
55 static LIST_HEAD(fs_uuids
);
57 void btrfs_lock_volumes(void)
59 mutex_lock(&uuid_mutex
);
62 void btrfs_unlock_volumes(void)
64 mutex_unlock(&uuid_mutex
);
67 static void lock_chunks(struct btrfs_root
*root
)
69 mutex_lock(&root
->fs_info
->chunk_mutex
);
72 static void unlock_chunks(struct btrfs_root
*root
)
74 mutex_unlock(&root
->fs_info
->chunk_mutex
);
77 static void free_fs_devices(struct btrfs_fs_devices
*fs_devices
)
79 struct btrfs_device
*device
;
80 WARN_ON(fs_devices
->opened
);
81 while (!list_empty(&fs_devices
->devices
)) {
82 device
= list_entry(fs_devices
->devices
.next
,
83 struct btrfs_device
, dev_list
);
84 list_del(&device
->dev_list
);
91 int btrfs_cleanup_fs_uuids(void)
93 struct btrfs_fs_devices
*fs_devices
;
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
);
104 static noinline
struct btrfs_device
*__find_device(struct list_head
*head
,
107 struct btrfs_device
*dev
;
109 list_for_each_entry(dev
, head
, dev_list
) {
110 if (dev
->devid
== devid
&&
111 (!uuid
|| !memcmp(dev
->uuid
, uuid
, BTRFS_UUID_SIZE
))) {
118 static noinline
struct btrfs_fs_devices
*find_fsid(u8
*fsid
)
120 struct btrfs_fs_devices
*fs_devices
;
122 list_for_each_entry(fs_devices
, &fs_uuids
, list
) {
123 if (memcmp(fsid
, fs_devices
->fsid
, BTRFS_FSID_SIZE
) == 0)
129 static void requeue_list(struct btrfs_pending_bios
*pending_bios
,
130 struct bio
*head
, struct bio
*tail
)
133 struct bio
*old_head
;
135 old_head
= pending_bios
->head
;
136 pending_bios
->head
= head
;
137 if (pending_bios
->tail
)
138 tail
->bi_next
= old_head
;
140 pending_bios
->tail
= tail
;
144 * we try to collect pending bios for a device so we don't get a large
145 * number of procs sending bios down to the same device. This greatly
146 * improves the schedulers ability to collect and merge the bios.
148 * But, it also turns into a long list of bios to process and that is sure
149 * to eventually make the worker thread block. The solution here is to
150 * make some progress and then put this work struct back at the end of
151 * the list if the block device is congested. This way, multiple devices
152 * can make progress from a single worker thread.
154 static noinline
int run_scheduled_bios(struct btrfs_device
*device
)
157 struct backing_dev_info
*bdi
;
158 struct btrfs_fs_info
*fs_info
;
159 struct btrfs_pending_bios
*pending_bios
;
163 unsigned long num_run
;
164 unsigned long num_sync_run
;
165 unsigned long batch_run
= 0;
167 unsigned long last_waited
= 0;
170 bdi
= blk_get_backing_dev_info(device
->bdev
);
171 fs_info
= device
->dev_root
->fs_info
;
172 limit
= btrfs_async_submit_limit(fs_info
);
173 limit
= limit
* 2 / 3;
175 /* we want to make sure that every time we switch from the sync
176 * list to the normal list, we unplug
181 spin_lock(&device
->io_lock
);
186 /* take all the bios off the list at once and process them
187 * later on (without the lock held). But, remember the
188 * tail and other pointers so the bios can be properly reinserted
189 * into the list if we hit congestion
191 if (!force_reg
&& device
->pending_sync_bios
.head
) {
192 pending_bios
= &device
->pending_sync_bios
;
195 pending_bios
= &device
->pending_bios
;
199 pending
= pending_bios
->head
;
200 tail
= pending_bios
->tail
;
201 WARN_ON(pending
&& !tail
);
204 * if pending was null this time around, no bios need processing
205 * at all and we can stop. Otherwise it'll loop back up again
206 * and do an additional check so no bios are missed.
208 * device->running_pending is used to synchronize with the
211 if (device
->pending_sync_bios
.head
== NULL
&&
212 device
->pending_bios
.head
== NULL
) {
214 device
->running_pending
= 0;
217 device
->running_pending
= 1;
220 pending_bios
->head
= NULL
;
221 pending_bios
->tail
= NULL
;
223 spin_unlock(&device
->io_lock
);
226 * if we're doing the regular priority list, make sure we unplug
227 * for any high prio bios we've sent down
229 if (pending_bios
== &device
->pending_bios
&& num_sync_run
> 0) {
231 blk_run_backing_dev(bdi
, NULL
);
237 /* we want to work on both lists, but do more bios on the
238 * sync list than the regular list
241 pending_bios
!= &device
->pending_sync_bios
&&
242 device
->pending_sync_bios
.head
) ||
243 (num_run
> 64 && pending_bios
== &device
->pending_sync_bios
&&
244 device
->pending_bios
.head
)) {
245 spin_lock(&device
->io_lock
);
246 requeue_list(pending_bios
, pending
, tail
);
251 pending
= pending
->bi_next
;
253 atomic_dec(&fs_info
->nr_async_bios
);
255 if (atomic_read(&fs_info
->nr_async_bios
) < limit
&&
256 waitqueue_active(&fs_info
->async_submit_wait
))
257 wake_up(&fs_info
->async_submit_wait
);
259 BUG_ON(atomic_read(&cur
->bi_cnt
) == 0);
261 if (cur
->bi_rw
& REQ_SYNC
)
264 submit_bio(cur
->bi_rw
, cur
);
267 if (need_resched()) {
269 blk_run_backing_dev(bdi
, NULL
);
276 * we made progress, there is more work to do and the bdi
277 * is now congested. Back off and let other work structs
280 if (pending
&& bdi_write_congested(bdi
) && batch_run
> 8 &&
281 fs_info
->fs_devices
->open_devices
> 1) {
282 struct io_context
*ioc
;
284 ioc
= current
->io_context
;
287 * the main goal here is that we don't want to
288 * block if we're going to be able to submit
289 * more requests without blocking.
291 * This code does two great things, it pokes into
292 * the elevator code from a filesystem _and_
293 * it makes assumptions about how batching works.
295 if (ioc
&& ioc
->nr_batch_requests
> 0 &&
296 time_before(jiffies
, ioc
->last_waited
+ HZ
/50UL) &&
298 ioc
->last_waited
== last_waited
)) {
300 * we want to go through our batch of
301 * requests and stop. So, we copy out
302 * the ioc->last_waited time and test
303 * against it before looping
305 last_waited
= ioc
->last_waited
;
306 if (need_resched()) {
308 blk_run_backing_dev(bdi
, NULL
);
315 spin_lock(&device
->io_lock
);
316 requeue_list(pending_bios
, pending
, tail
);
317 device
->running_pending
= 1;
319 spin_unlock(&device
->io_lock
);
320 btrfs_requeue_work(&device
->work
);
327 blk_run_backing_dev(bdi
, NULL
);
330 * IO has already been through a long path to get here. Checksumming,
331 * async helper threads, perhaps compression. We've done a pretty
332 * good job of collecting a batch of IO and should just unplug
333 * the device right away.
335 * This will help anyone who is waiting on the IO, they might have
336 * already unplugged, but managed to do so before the bio they
337 * cared about found its way down here.
339 blk_run_backing_dev(bdi
, NULL
);
345 spin_lock(&device
->io_lock
);
346 if (device
->pending_bios
.head
|| device
->pending_sync_bios
.head
)
348 spin_unlock(&device
->io_lock
);
354 static void pending_bios_fn(struct btrfs_work
*work
)
356 struct btrfs_device
*device
;
358 device
= container_of(work
, struct btrfs_device
, work
);
359 run_scheduled_bios(device
);
362 static noinline
int device_list_add(const char *path
,
363 struct btrfs_super_block
*disk_super
,
364 u64 devid
, struct btrfs_fs_devices
**fs_devices_ret
)
366 struct btrfs_device
*device
;
367 struct btrfs_fs_devices
*fs_devices
;
368 u64 found_transid
= btrfs_super_generation(disk_super
);
371 fs_devices
= find_fsid(disk_super
->fsid
);
373 fs_devices
= kzalloc(sizeof(*fs_devices
), GFP_NOFS
);
376 INIT_LIST_HEAD(&fs_devices
->devices
);
377 INIT_LIST_HEAD(&fs_devices
->alloc_list
);
378 list_add(&fs_devices
->list
, &fs_uuids
);
379 memcpy(fs_devices
->fsid
, disk_super
->fsid
, BTRFS_FSID_SIZE
);
380 fs_devices
->latest_devid
= devid
;
381 fs_devices
->latest_trans
= found_transid
;
382 mutex_init(&fs_devices
->device_list_mutex
);
385 device
= __find_device(&fs_devices
->devices
, devid
,
386 disk_super
->dev_item
.uuid
);
389 if (fs_devices
->opened
)
392 device
= kzalloc(sizeof(*device
), GFP_NOFS
);
394 /* we can safely leave the fs_devices entry around */
397 device
->devid
= devid
;
398 device
->work
.func
= pending_bios_fn
;
399 memcpy(device
->uuid
, disk_super
->dev_item
.uuid
,
401 spin_lock_init(&device
->io_lock
);
402 device
->name
= kstrdup(path
, GFP_NOFS
);
407 INIT_LIST_HEAD(&device
->dev_alloc_list
);
409 mutex_lock(&fs_devices
->device_list_mutex
);
410 list_add(&device
->dev_list
, &fs_devices
->devices
);
411 mutex_unlock(&fs_devices
->device_list_mutex
);
413 device
->fs_devices
= fs_devices
;
414 fs_devices
->num_devices
++;
415 } else if (!device
->name
|| strcmp(device
->name
, path
)) {
416 name
= kstrdup(path
, GFP_NOFS
);
421 if (device
->missing
) {
422 fs_devices
->missing_devices
--;
427 if (found_transid
> fs_devices
->latest_trans
) {
428 fs_devices
->latest_devid
= devid
;
429 fs_devices
->latest_trans
= found_transid
;
431 *fs_devices_ret
= fs_devices
;
435 static struct btrfs_fs_devices
*clone_fs_devices(struct btrfs_fs_devices
*orig
)
437 struct btrfs_fs_devices
*fs_devices
;
438 struct btrfs_device
*device
;
439 struct btrfs_device
*orig_dev
;
441 fs_devices
= kzalloc(sizeof(*fs_devices
), GFP_NOFS
);
443 return ERR_PTR(-ENOMEM
);
445 INIT_LIST_HEAD(&fs_devices
->devices
);
446 INIT_LIST_HEAD(&fs_devices
->alloc_list
);
447 INIT_LIST_HEAD(&fs_devices
->list
);
448 mutex_init(&fs_devices
->device_list_mutex
);
449 fs_devices
->latest_devid
= orig
->latest_devid
;
450 fs_devices
->latest_trans
= orig
->latest_trans
;
451 memcpy(fs_devices
->fsid
, orig
->fsid
, sizeof(fs_devices
->fsid
));
453 mutex_lock(&orig
->device_list_mutex
);
454 list_for_each_entry(orig_dev
, &orig
->devices
, dev_list
) {
455 device
= kzalloc(sizeof(*device
), GFP_NOFS
);
459 device
->name
= kstrdup(orig_dev
->name
, GFP_NOFS
);
465 device
->devid
= orig_dev
->devid
;
466 device
->work
.func
= pending_bios_fn
;
467 memcpy(device
->uuid
, orig_dev
->uuid
, sizeof(device
->uuid
));
468 spin_lock_init(&device
->io_lock
);
469 INIT_LIST_HEAD(&device
->dev_list
);
470 INIT_LIST_HEAD(&device
->dev_alloc_list
);
472 list_add(&device
->dev_list
, &fs_devices
->devices
);
473 device
->fs_devices
= fs_devices
;
474 fs_devices
->num_devices
++;
476 mutex_unlock(&orig
->device_list_mutex
);
479 mutex_unlock(&orig
->device_list_mutex
);
480 free_fs_devices(fs_devices
);
481 return ERR_PTR(-ENOMEM
);
484 int btrfs_close_extra_devices(struct btrfs_fs_devices
*fs_devices
)
486 struct btrfs_device
*device
, *next
;
488 mutex_lock(&uuid_mutex
);
490 mutex_lock(&fs_devices
->device_list_mutex
);
491 list_for_each_entry_safe(device
, next
, &fs_devices
->devices
, dev_list
) {
492 if (device
->in_fs_metadata
)
496 close_bdev_exclusive(device
->bdev
, device
->mode
);
498 fs_devices
->open_devices
--;
500 if (device
->writeable
) {
501 list_del_init(&device
->dev_alloc_list
);
502 device
->writeable
= 0;
503 fs_devices
->rw_devices
--;
505 list_del_init(&device
->dev_list
);
506 fs_devices
->num_devices
--;
510 mutex_unlock(&fs_devices
->device_list_mutex
);
512 if (fs_devices
->seed
) {
513 fs_devices
= fs_devices
->seed
;
517 mutex_unlock(&uuid_mutex
);
521 static int __btrfs_close_devices(struct btrfs_fs_devices
*fs_devices
)
523 struct btrfs_device
*device
;
525 if (--fs_devices
->opened
> 0)
528 list_for_each_entry(device
, &fs_devices
->devices
, dev_list
) {
530 close_bdev_exclusive(device
->bdev
, device
->mode
);
531 fs_devices
->open_devices
--;
533 if (device
->writeable
) {
534 list_del_init(&device
->dev_alloc_list
);
535 fs_devices
->rw_devices
--;
539 device
->writeable
= 0;
540 device
->in_fs_metadata
= 0;
542 WARN_ON(fs_devices
->open_devices
);
543 WARN_ON(fs_devices
->rw_devices
);
544 fs_devices
->opened
= 0;
545 fs_devices
->seeding
= 0;
550 int btrfs_close_devices(struct btrfs_fs_devices
*fs_devices
)
552 struct btrfs_fs_devices
*seed_devices
= NULL
;
555 mutex_lock(&uuid_mutex
);
556 ret
= __btrfs_close_devices(fs_devices
);
557 if (!fs_devices
->opened
) {
558 seed_devices
= fs_devices
->seed
;
559 fs_devices
->seed
= NULL
;
561 mutex_unlock(&uuid_mutex
);
563 while (seed_devices
) {
564 fs_devices
= seed_devices
;
565 seed_devices
= fs_devices
->seed
;
566 __btrfs_close_devices(fs_devices
);
567 free_fs_devices(fs_devices
);
572 static int __btrfs_open_devices(struct btrfs_fs_devices
*fs_devices
,
573 fmode_t flags
, void *holder
)
575 struct block_device
*bdev
;
576 struct list_head
*head
= &fs_devices
->devices
;
577 struct btrfs_device
*device
;
578 struct block_device
*latest_bdev
= NULL
;
579 struct buffer_head
*bh
;
580 struct btrfs_super_block
*disk_super
;
581 u64 latest_devid
= 0;
582 u64 latest_transid
= 0;
587 list_for_each_entry(device
, head
, dev_list
) {
593 bdev
= open_bdev_exclusive(device
->name
, flags
, holder
);
595 printk(KERN_INFO
"open %s failed\n", device
->name
);
598 set_blocksize(bdev
, 4096);
600 bh
= btrfs_read_dev_super(bdev
);
604 disk_super
= (struct btrfs_super_block
*)bh
->b_data
;
605 devid
= btrfs_stack_device_id(&disk_super
->dev_item
);
606 if (devid
!= device
->devid
)
609 if (memcmp(device
->uuid
, disk_super
->dev_item
.uuid
,
613 device
->generation
= btrfs_super_generation(disk_super
);
614 if (!latest_transid
|| device
->generation
> latest_transid
) {
615 latest_devid
= devid
;
616 latest_transid
= device
->generation
;
620 if (btrfs_super_flags(disk_super
) & BTRFS_SUPER_FLAG_SEEDING
) {
621 device
->writeable
= 0;
623 device
->writeable
= !bdev_read_only(bdev
);
628 device
->in_fs_metadata
= 0;
629 device
->mode
= flags
;
631 if (!blk_queue_nonrot(bdev_get_queue(bdev
)))
632 fs_devices
->rotating
= 1;
634 fs_devices
->open_devices
++;
635 if (device
->writeable
) {
636 fs_devices
->rw_devices
++;
637 list_add(&device
->dev_alloc_list
,
638 &fs_devices
->alloc_list
);
645 close_bdev_exclusive(bdev
, FMODE_READ
);
649 if (fs_devices
->open_devices
== 0) {
653 fs_devices
->seeding
= seeding
;
654 fs_devices
->opened
= 1;
655 fs_devices
->latest_bdev
= latest_bdev
;
656 fs_devices
->latest_devid
= latest_devid
;
657 fs_devices
->latest_trans
= latest_transid
;
658 fs_devices
->total_rw_bytes
= 0;
663 int btrfs_open_devices(struct btrfs_fs_devices
*fs_devices
,
664 fmode_t flags
, void *holder
)
668 mutex_lock(&uuid_mutex
);
669 if (fs_devices
->opened
) {
670 fs_devices
->opened
++;
673 ret
= __btrfs_open_devices(fs_devices
, flags
, holder
);
675 mutex_unlock(&uuid_mutex
);
679 int btrfs_scan_one_device(const char *path
, fmode_t flags
, void *holder
,
680 struct btrfs_fs_devices
**fs_devices_ret
)
682 struct btrfs_super_block
*disk_super
;
683 struct block_device
*bdev
;
684 struct buffer_head
*bh
;
689 mutex_lock(&uuid_mutex
);
691 bdev
= open_bdev_exclusive(path
, flags
, holder
);
698 ret
= set_blocksize(bdev
, 4096);
701 bh
= btrfs_read_dev_super(bdev
);
706 disk_super
= (struct btrfs_super_block
*)bh
->b_data
;
707 devid
= btrfs_stack_device_id(&disk_super
->dev_item
);
708 transid
= btrfs_super_generation(disk_super
);
709 if (disk_super
->label
[0])
710 printk(KERN_INFO
"device label %s ", disk_super
->label
);
712 /* FIXME, make a readl uuid parser */
713 printk(KERN_INFO
"device fsid %llx-%llx ",
714 *(unsigned long long *)disk_super
->fsid
,
715 *(unsigned long long *)(disk_super
->fsid
+ 8));
717 printk(KERN_CONT
"devid %llu transid %llu %s\n",
718 (unsigned long long)devid
, (unsigned long long)transid
, path
);
719 ret
= device_list_add(path
, disk_super
, devid
, fs_devices_ret
);
723 close_bdev_exclusive(bdev
, flags
);
725 mutex_unlock(&uuid_mutex
);
730 * this uses a pretty simple search, the expectation is that it is
731 * called very infrequently and that a given device has a small number
734 int find_free_dev_extent(struct btrfs_trans_handle
*trans
,
735 struct btrfs_device
*device
, u64 num_bytes
,
736 u64
*start
, u64
*max_avail
)
738 struct btrfs_key key
;
739 struct btrfs_root
*root
= device
->dev_root
;
740 struct btrfs_dev_extent
*dev_extent
= NULL
;
741 struct btrfs_path
*path
;
744 u64 search_start
= 0;
745 u64 search_end
= device
->total_bytes
;
749 struct extent_buffer
*l
;
751 path
= btrfs_alloc_path();
757 /* FIXME use last free of some kind */
759 /* we don't want to overwrite the superblock on the drive,
760 * so we make sure to start at an offset of at least 1MB
762 search_start
= max((u64
)1024 * 1024, search_start
);
764 if (root
->fs_info
->alloc_start
+ num_bytes
<= device
->total_bytes
)
765 search_start
= max(root
->fs_info
->alloc_start
, search_start
);
767 key
.objectid
= device
->devid
;
768 key
.offset
= search_start
;
769 key
.type
= BTRFS_DEV_EXTENT_KEY
;
770 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 0);
774 ret
= btrfs_previous_item(root
, path
, key
.objectid
, key
.type
);
781 btrfs_item_key_to_cpu(l
, &key
, path
->slots
[0]);
784 slot
= path
->slots
[0];
785 if (slot
>= btrfs_header_nritems(l
)) {
786 ret
= btrfs_next_leaf(root
, path
);
793 if (search_start
>= search_end
) {
797 *start
= search_start
;
801 *start
= last_byte
> search_start
?
802 last_byte
: search_start
;
803 if (search_end
<= *start
) {
809 btrfs_item_key_to_cpu(l
, &key
, slot
);
811 if (key
.objectid
< device
->devid
)
814 if (key
.objectid
> device
->devid
)
817 if (key
.offset
>= search_start
&& key
.offset
> last_byte
&&
819 if (last_byte
< search_start
)
820 last_byte
= search_start
;
821 hole_size
= key
.offset
- last_byte
;
823 if (hole_size
> *max_avail
)
824 *max_avail
= hole_size
;
826 if (key
.offset
> last_byte
&&
827 hole_size
>= num_bytes
) {
832 if (btrfs_key_type(&key
) != BTRFS_DEV_EXTENT_KEY
)
836 dev_extent
= btrfs_item_ptr(l
, slot
, struct btrfs_dev_extent
);
837 last_byte
= key
.offset
+ btrfs_dev_extent_length(l
, dev_extent
);
843 /* we have to make sure we didn't find an extent that has already
844 * been allocated by the map tree or the original allocation
846 BUG_ON(*start
< search_start
);
848 if (*start
+ num_bytes
> search_end
) {
852 /* check for pending inserts here */
856 btrfs_free_path(path
);
860 static int btrfs_free_dev_extent(struct btrfs_trans_handle
*trans
,
861 struct btrfs_device
*device
,
865 struct btrfs_path
*path
;
866 struct btrfs_root
*root
= device
->dev_root
;
867 struct btrfs_key key
;
868 struct btrfs_key found_key
;
869 struct extent_buffer
*leaf
= NULL
;
870 struct btrfs_dev_extent
*extent
= NULL
;
872 path
= btrfs_alloc_path();
876 key
.objectid
= device
->devid
;
878 key
.type
= BTRFS_DEV_EXTENT_KEY
;
880 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
882 ret
= btrfs_previous_item(root
, path
, key
.objectid
,
883 BTRFS_DEV_EXTENT_KEY
);
885 leaf
= path
->nodes
[0];
886 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
887 extent
= btrfs_item_ptr(leaf
, path
->slots
[0],
888 struct btrfs_dev_extent
);
889 BUG_ON(found_key
.offset
> start
|| found_key
.offset
+
890 btrfs_dev_extent_length(leaf
, extent
) < start
);
892 } else if (ret
== 0) {
893 leaf
= path
->nodes
[0];
894 extent
= btrfs_item_ptr(leaf
, path
->slots
[0],
895 struct btrfs_dev_extent
);
899 if (device
->bytes_used
> 0)
900 device
->bytes_used
-= btrfs_dev_extent_length(leaf
, extent
);
901 ret
= btrfs_del_item(trans
, root
, path
);
904 btrfs_free_path(path
);
908 int btrfs_alloc_dev_extent(struct btrfs_trans_handle
*trans
,
909 struct btrfs_device
*device
,
910 u64 chunk_tree
, u64 chunk_objectid
,
911 u64 chunk_offset
, u64 start
, u64 num_bytes
)
914 struct btrfs_path
*path
;
915 struct btrfs_root
*root
= device
->dev_root
;
916 struct btrfs_dev_extent
*extent
;
917 struct extent_buffer
*leaf
;
918 struct btrfs_key key
;
920 WARN_ON(!device
->in_fs_metadata
);
921 path
= btrfs_alloc_path();
925 key
.objectid
= device
->devid
;
927 key
.type
= BTRFS_DEV_EXTENT_KEY
;
928 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
,
932 leaf
= path
->nodes
[0];
933 extent
= btrfs_item_ptr(leaf
, path
->slots
[0],
934 struct btrfs_dev_extent
);
935 btrfs_set_dev_extent_chunk_tree(leaf
, extent
, chunk_tree
);
936 btrfs_set_dev_extent_chunk_objectid(leaf
, extent
, chunk_objectid
);
937 btrfs_set_dev_extent_chunk_offset(leaf
, extent
, chunk_offset
);
939 write_extent_buffer(leaf
, root
->fs_info
->chunk_tree_uuid
,
940 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent
),
943 btrfs_set_dev_extent_length(leaf
, extent
, num_bytes
);
944 btrfs_mark_buffer_dirty(leaf
);
945 btrfs_free_path(path
);
949 static noinline
int find_next_chunk(struct btrfs_root
*root
,
950 u64 objectid
, u64
*offset
)
952 struct btrfs_path
*path
;
954 struct btrfs_key key
;
955 struct btrfs_chunk
*chunk
;
956 struct btrfs_key found_key
;
958 path
= btrfs_alloc_path();
961 key
.objectid
= objectid
;
962 key
.offset
= (u64
)-1;
963 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
965 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
971 ret
= btrfs_previous_item(root
, path
, 0, BTRFS_CHUNK_ITEM_KEY
);
975 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
977 if (found_key
.objectid
!= objectid
)
980 chunk
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
982 *offset
= found_key
.offset
+
983 btrfs_chunk_length(path
->nodes
[0], chunk
);
988 btrfs_free_path(path
);
992 static noinline
int find_next_devid(struct btrfs_root
*root
, u64
*objectid
)
995 struct btrfs_key key
;
996 struct btrfs_key found_key
;
997 struct btrfs_path
*path
;
999 root
= root
->fs_info
->chunk_root
;
1001 path
= btrfs_alloc_path();
1005 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
1006 key
.type
= BTRFS_DEV_ITEM_KEY
;
1007 key
.offset
= (u64
)-1;
1009 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
1015 ret
= btrfs_previous_item(root
, path
, BTRFS_DEV_ITEMS_OBJECTID
,
1016 BTRFS_DEV_ITEM_KEY
);
1020 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
1022 *objectid
= found_key
.offset
+ 1;
1026 btrfs_free_path(path
);
1031 * the device information is stored in the chunk root
1032 * the btrfs_device struct should be fully filled in
1034 int btrfs_add_device(struct btrfs_trans_handle
*trans
,
1035 struct btrfs_root
*root
,
1036 struct btrfs_device
*device
)
1039 struct btrfs_path
*path
;
1040 struct btrfs_dev_item
*dev_item
;
1041 struct extent_buffer
*leaf
;
1042 struct btrfs_key key
;
1045 root
= root
->fs_info
->chunk_root
;
1047 path
= btrfs_alloc_path();
1051 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
1052 key
.type
= BTRFS_DEV_ITEM_KEY
;
1053 key
.offset
= device
->devid
;
1055 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
,
1060 leaf
= path
->nodes
[0];
1061 dev_item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_dev_item
);
1063 btrfs_set_device_id(leaf
, dev_item
, device
->devid
);
1064 btrfs_set_device_generation(leaf
, dev_item
, 0);
1065 btrfs_set_device_type(leaf
, dev_item
, device
->type
);
1066 btrfs_set_device_io_align(leaf
, dev_item
, device
->io_align
);
1067 btrfs_set_device_io_width(leaf
, dev_item
, device
->io_width
);
1068 btrfs_set_device_sector_size(leaf
, dev_item
, device
->sector_size
);
1069 btrfs_set_device_total_bytes(leaf
, dev_item
, device
->total_bytes
);
1070 btrfs_set_device_bytes_used(leaf
, dev_item
, device
->bytes_used
);
1071 btrfs_set_device_group(leaf
, dev_item
, 0);
1072 btrfs_set_device_seek_speed(leaf
, dev_item
, 0);
1073 btrfs_set_device_bandwidth(leaf
, dev_item
, 0);
1074 btrfs_set_device_start_offset(leaf
, dev_item
, 0);
1076 ptr
= (unsigned long)btrfs_device_uuid(dev_item
);
1077 write_extent_buffer(leaf
, device
->uuid
, ptr
, BTRFS_UUID_SIZE
);
1078 ptr
= (unsigned long)btrfs_device_fsid(dev_item
);
1079 write_extent_buffer(leaf
, root
->fs_info
->fsid
, ptr
, BTRFS_UUID_SIZE
);
1080 btrfs_mark_buffer_dirty(leaf
);
1084 btrfs_free_path(path
);
1088 static int btrfs_rm_dev_item(struct btrfs_root
*root
,
1089 struct btrfs_device
*device
)
1092 struct btrfs_path
*path
;
1093 struct btrfs_key key
;
1094 struct btrfs_trans_handle
*trans
;
1096 root
= root
->fs_info
->chunk_root
;
1098 path
= btrfs_alloc_path();
1102 trans
= btrfs_start_transaction(root
, 0);
1103 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
1104 key
.type
= BTRFS_DEV_ITEM_KEY
;
1105 key
.offset
= device
->devid
;
1108 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1117 ret
= btrfs_del_item(trans
, root
, path
);
1121 btrfs_free_path(path
);
1122 unlock_chunks(root
);
1123 btrfs_commit_transaction(trans
, root
);
1127 int btrfs_rm_device(struct btrfs_root
*root
, char *device_path
)
1129 struct btrfs_device
*device
;
1130 struct btrfs_device
*next_device
;
1131 struct block_device
*bdev
;
1132 struct buffer_head
*bh
= NULL
;
1133 struct btrfs_super_block
*disk_super
;
1140 mutex_lock(&uuid_mutex
);
1141 mutex_lock(&root
->fs_info
->volume_mutex
);
1143 all_avail
= root
->fs_info
->avail_data_alloc_bits
|
1144 root
->fs_info
->avail_system_alloc_bits
|
1145 root
->fs_info
->avail_metadata_alloc_bits
;
1147 if ((all_avail
& BTRFS_BLOCK_GROUP_RAID10
) &&
1148 root
->fs_info
->fs_devices
->num_devices
<= 4) {
1149 printk(KERN_ERR
"btrfs: unable to go below four devices "
1155 if ((all_avail
& BTRFS_BLOCK_GROUP_RAID1
) &&
1156 root
->fs_info
->fs_devices
->num_devices
<= 2) {
1157 printk(KERN_ERR
"btrfs: unable to go below two "
1158 "devices on raid1\n");
1163 if (strcmp(device_path
, "missing") == 0) {
1164 struct list_head
*devices
;
1165 struct btrfs_device
*tmp
;
1168 devices
= &root
->fs_info
->fs_devices
->devices
;
1169 mutex_lock(&root
->fs_info
->fs_devices
->device_list_mutex
);
1170 list_for_each_entry(tmp
, devices
, dev_list
) {
1171 if (tmp
->in_fs_metadata
&& !tmp
->bdev
) {
1176 mutex_unlock(&root
->fs_info
->fs_devices
->device_list_mutex
);
1181 printk(KERN_ERR
"btrfs: no missing devices found to "
1186 bdev
= open_bdev_exclusive(device_path
, FMODE_READ
,
1187 root
->fs_info
->bdev_holder
);
1189 ret
= PTR_ERR(bdev
);
1193 set_blocksize(bdev
, 4096);
1194 bh
= btrfs_read_dev_super(bdev
);
1199 disk_super
= (struct btrfs_super_block
*)bh
->b_data
;
1200 devid
= btrfs_stack_device_id(&disk_super
->dev_item
);
1201 dev_uuid
= disk_super
->dev_item
.uuid
;
1202 device
= btrfs_find_device(root
, devid
, dev_uuid
,
1210 if (device
->writeable
&& root
->fs_info
->fs_devices
->rw_devices
== 1) {
1211 printk(KERN_ERR
"btrfs: unable to remove the only writeable "
1217 if (device
->writeable
) {
1218 list_del_init(&device
->dev_alloc_list
);
1219 root
->fs_info
->fs_devices
->rw_devices
--;
1222 ret
= btrfs_shrink_device(device
, 0);
1226 ret
= btrfs_rm_dev_item(root
->fs_info
->chunk_root
, device
);
1230 device
->in_fs_metadata
= 0;
1233 * the device list mutex makes sure that we don't change
1234 * the device list while someone else is writing out all
1235 * the device supers.
1237 mutex_lock(&root
->fs_info
->fs_devices
->device_list_mutex
);
1238 list_del_init(&device
->dev_list
);
1239 mutex_unlock(&root
->fs_info
->fs_devices
->device_list_mutex
);
1241 device
->fs_devices
->num_devices
--;
1243 if (device
->missing
)
1244 root
->fs_info
->fs_devices
->missing_devices
--;
1246 next_device
= list_entry(root
->fs_info
->fs_devices
->devices
.next
,
1247 struct btrfs_device
, dev_list
);
1248 if (device
->bdev
== root
->fs_info
->sb
->s_bdev
)
1249 root
->fs_info
->sb
->s_bdev
= next_device
->bdev
;
1250 if (device
->bdev
== root
->fs_info
->fs_devices
->latest_bdev
)
1251 root
->fs_info
->fs_devices
->latest_bdev
= next_device
->bdev
;
1254 close_bdev_exclusive(device
->bdev
, device
->mode
);
1255 device
->bdev
= NULL
;
1256 device
->fs_devices
->open_devices
--;
1259 num_devices
= btrfs_super_num_devices(&root
->fs_info
->super_copy
) - 1;
1260 btrfs_set_super_num_devices(&root
->fs_info
->super_copy
, num_devices
);
1262 if (device
->fs_devices
->open_devices
== 0) {
1263 struct btrfs_fs_devices
*fs_devices
;
1264 fs_devices
= root
->fs_info
->fs_devices
;
1265 while (fs_devices
) {
1266 if (fs_devices
->seed
== device
->fs_devices
)
1268 fs_devices
= fs_devices
->seed
;
1270 fs_devices
->seed
= device
->fs_devices
->seed
;
1271 device
->fs_devices
->seed
= NULL
;
1272 __btrfs_close_devices(device
->fs_devices
);
1273 free_fs_devices(device
->fs_devices
);
1277 * at this point, the device is zero sized. We want to
1278 * remove it from the devices list and zero out the old super
1280 if (device
->writeable
) {
1281 /* make sure this device isn't detected as part of
1284 memset(&disk_super
->magic
, 0, sizeof(disk_super
->magic
));
1285 set_buffer_dirty(bh
);
1286 sync_dirty_buffer(bh
);
1289 kfree(device
->name
);
1297 close_bdev_exclusive(bdev
, FMODE_READ
);
1299 mutex_unlock(&root
->fs_info
->volume_mutex
);
1300 mutex_unlock(&uuid_mutex
);
1305 * does all the dirty work required for changing file system's UUID.
1307 static int btrfs_prepare_sprout(struct btrfs_trans_handle
*trans
,
1308 struct btrfs_root
*root
)
1310 struct btrfs_fs_devices
*fs_devices
= root
->fs_info
->fs_devices
;
1311 struct btrfs_fs_devices
*old_devices
;
1312 struct btrfs_fs_devices
*seed_devices
;
1313 struct btrfs_super_block
*disk_super
= &root
->fs_info
->super_copy
;
1314 struct btrfs_device
*device
;
1317 BUG_ON(!mutex_is_locked(&uuid_mutex
));
1318 if (!fs_devices
->seeding
)
1321 seed_devices
= kzalloc(sizeof(*fs_devices
), GFP_NOFS
);
1325 old_devices
= clone_fs_devices(fs_devices
);
1326 if (IS_ERR(old_devices
)) {
1327 kfree(seed_devices
);
1328 return PTR_ERR(old_devices
);
1331 list_add(&old_devices
->list
, &fs_uuids
);
1333 memcpy(seed_devices
, fs_devices
, sizeof(*seed_devices
));
1334 seed_devices
->opened
= 1;
1335 INIT_LIST_HEAD(&seed_devices
->devices
);
1336 INIT_LIST_HEAD(&seed_devices
->alloc_list
);
1337 mutex_init(&seed_devices
->device_list_mutex
);
1338 list_splice_init(&fs_devices
->devices
, &seed_devices
->devices
);
1339 list_splice_init(&fs_devices
->alloc_list
, &seed_devices
->alloc_list
);
1340 list_for_each_entry(device
, &seed_devices
->devices
, dev_list
) {
1341 device
->fs_devices
= seed_devices
;
1344 fs_devices
->seeding
= 0;
1345 fs_devices
->num_devices
= 0;
1346 fs_devices
->open_devices
= 0;
1347 fs_devices
->seed
= seed_devices
;
1349 generate_random_uuid(fs_devices
->fsid
);
1350 memcpy(root
->fs_info
->fsid
, fs_devices
->fsid
, BTRFS_FSID_SIZE
);
1351 memcpy(disk_super
->fsid
, fs_devices
->fsid
, BTRFS_FSID_SIZE
);
1352 super_flags
= btrfs_super_flags(disk_super
) &
1353 ~BTRFS_SUPER_FLAG_SEEDING
;
1354 btrfs_set_super_flags(disk_super
, super_flags
);
1360 * strore the expected generation for seed devices in device items.
1362 static int btrfs_finish_sprout(struct btrfs_trans_handle
*trans
,
1363 struct btrfs_root
*root
)
1365 struct btrfs_path
*path
;
1366 struct extent_buffer
*leaf
;
1367 struct btrfs_dev_item
*dev_item
;
1368 struct btrfs_device
*device
;
1369 struct btrfs_key key
;
1370 u8 fs_uuid
[BTRFS_UUID_SIZE
];
1371 u8 dev_uuid
[BTRFS_UUID_SIZE
];
1375 path
= btrfs_alloc_path();
1379 root
= root
->fs_info
->chunk_root
;
1380 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
1382 key
.type
= BTRFS_DEV_ITEM_KEY
;
1385 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
1389 leaf
= path
->nodes
[0];
1391 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
1392 ret
= btrfs_next_leaf(root
, path
);
1397 leaf
= path
->nodes
[0];
1398 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1399 btrfs_release_path(root
, path
);
1403 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
1404 if (key
.objectid
!= BTRFS_DEV_ITEMS_OBJECTID
||
1405 key
.type
!= BTRFS_DEV_ITEM_KEY
)
1408 dev_item
= btrfs_item_ptr(leaf
, path
->slots
[0],
1409 struct btrfs_dev_item
);
1410 devid
= btrfs_device_id(leaf
, dev_item
);
1411 read_extent_buffer(leaf
, dev_uuid
,
1412 (unsigned long)btrfs_device_uuid(dev_item
),
1414 read_extent_buffer(leaf
, fs_uuid
,
1415 (unsigned long)btrfs_device_fsid(dev_item
),
1417 device
= btrfs_find_device(root
, devid
, dev_uuid
, fs_uuid
);
1420 if (device
->fs_devices
->seeding
) {
1421 btrfs_set_device_generation(leaf
, dev_item
,
1422 device
->generation
);
1423 btrfs_mark_buffer_dirty(leaf
);
1431 btrfs_free_path(path
);
1435 int btrfs_init_new_device(struct btrfs_root
*root
, char *device_path
)
1437 struct btrfs_trans_handle
*trans
;
1438 struct btrfs_device
*device
;
1439 struct block_device
*bdev
;
1440 struct list_head
*devices
;
1441 struct super_block
*sb
= root
->fs_info
->sb
;
1443 int seeding_dev
= 0;
1446 if ((sb
->s_flags
& MS_RDONLY
) && !root
->fs_info
->fs_devices
->seeding
)
1449 bdev
= open_bdev_exclusive(device_path
, 0, root
->fs_info
->bdev_holder
);
1451 return PTR_ERR(bdev
);
1453 if (root
->fs_info
->fs_devices
->seeding
) {
1455 down_write(&sb
->s_umount
);
1456 mutex_lock(&uuid_mutex
);
1459 filemap_write_and_wait(bdev
->bd_inode
->i_mapping
);
1460 mutex_lock(&root
->fs_info
->volume_mutex
);
1462 devices
= &root
->fs_info
->fs_devices
->devices
;
1464 * we have the volume lock, so we don't need the extra
1465 * device list mutex while reading the list here.
1467 list_for_each_entry(device
, devices
, dev_list
) {
1468 if (device
->bdev
== bdev
) {
1474 device
= kzalloc(sizeof(*device
), GFP_NOFS
);
1476 /* we can safely leave the fs_devices entry around */
1481 device
->name
= kstrdup(device_path
, GFP_NOFS
);
1482 if (!device
->name
) {
1488 ret
= find_next_devid(root
, &device
->devid
);
1494 trans
= btrfs_start_transaction(root
, 0);
1497 device
->writeable
= 1;
1498 device
->work
.func
= pending_bios_fn
;
1499 generate_random_uuid(device
->uuid
);
1500 spin_lock_init(&device
->io_lock
);
1501 device
->generation
= trans
->transid
;
1502 device
->io_width
= root
->sectorsize
;
1503 device
->io_align
= root
->sectorsize
;
1504 device
->sector_size
= root
->sectorsize
;
1505 device
->total_bytes
= i_size_read(bdev
->bd_inode
);
1506 device
->disk_total_bytes
= device
->total_bytes
;
1507 device
->dev_root
= root
->fs_info
->dev_root
;
1508 device
->bdev
= bdev
;
1509 device
->in_fs_metadata
= 1;
1511 set_blocksize(device
->bdev
, 4096);
1514 sb
->s_flags
&= ~MS_RDONLY
;
1515 ret
= btrfs_prepare_sprout(trans
, root
);
1519 device
->fs_devices
= root
->fs_info
->fs_devices
;
1522 * we don't want write_supers to jump in here with our device
1525 mutex_lock(&root
->fs_info
->fs_devices
->device_list_mutex
);
1526 list_add(&device
->dev_list
, &root
->fs_info
->fs_devices
->devices
);
1527 list_add(&device
->dev_alloc_list
,
1528 &root
->fs_info
->fs_devices
->alloc_list
);
1529 root
->fs_info
->fs_devices
->num_devices
++;
1530 root
->fs_info
->fs_devices
->open_devices
++;
1531 root
->fs_info
->fs_devices
->rw_devices
++;
1532 root
->fs_info
->fs_devices
->total_rw_bytes
+= device
->total_bytes
;
1534 if (!blk_queue_nonrot(bdev_get_queue(bdev
)))
1535 root
->fs_info
->fs_devices
->rotating
= 1;
1537 total_bytes
= btrfs_super_total_bytes(&root
->fs_info
->super_copy
);
1538 btrfs_set_super_total_bytes(&root
->fs_info
->super_copy
,
1539 total_bytes
+ device
->total_bytes
);
1541 total_bytes
= btrfs_super_num_devices(&root
->fs_info
->super_copy
);
1542 btrfs_set_super_num_devices(&root
->fs_info
->super_copy
,
1544 mutex_unlock(&root
->fs_info
->fs_devices
->device_list_mutex
);
1547 ret
= init_first_rw_device(trans
, root
, device
);
1549 ret
= btrfs_finish_sprout(trans
, root
);
1552 ret
= btrfs_add_device(trans
, root
, device
);
1556 * we've got more storage, clear any full flags on the space
1559 btrfs_clear_space_info_full(root
->fs_info
);
1561 unlock_chunks(root
);
1562 btrfs_commit_transaction(trans
, root
);
1565 mutex_unlock(&uuid_mutex
);
1566 up_write(&sb
->s_umount
);
1568 ret
= btrfs_relocate_sys_chunks(root
);
1572 mutex_unlock(&root
->fs_info
->volume_mutex
);
1575 close_bdev_exclusive(bdev
, 0);
1577 mutex_unlock(&uuid_mutex
);
1578 up_write(&sb
->s_umount
);
1583 static noinline
int btrfs_update_device(struct btrfs_trans_handle
*trans
,
1584 struct btrfs_device
*device
)
1587 struct btrfs_path
*path
;
1588 struct btrfs_root
*root
;
1589 struct btrfs_dev_item
*dev_item
;
1590 struct extent_buffer
*leaf
;
1591 struct btrfs_key key
;
1593 root
= device
->dev_root
->fs_info
->chunk_root
;
1595 path
= btrfs_alloc_path();
1599 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
1600 key
.type
= BTRFS_DEV_ITEM_KEY
;
1601 key
.offset
= device
->devid
;
1603 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
1612 leaf
= path
->nodes
[0];
1613 dev_item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_dev_item
);
1615 btrfs_set_device_id(leaf
, dev_item
, device
->devid
);
1616 btrfs_set_device_type(leaf
, dev_item
, device
->type
);
1617 btrfs_set_device_io_align(leaf
, dev_item
, device
->io_align
);
1618 btrfs_set_device_io_width(leaf
, dev_item
, device
->io_width
);
1619 btrfs_set_device_sector_size(leaf
, dev_item
, device
->sector_size
);
1620 btrfs_set_device_total_bytes(leaf
, dev_item
, device
->disk_total_bytes
);
1621 btrfs_set_device_bytes_used(leaf
, dev_item
, device
->bytes_used
);
1622 btrfs_mark_buffer_dirty(leaf
);
1625 btrfs_free_path(path
);
1629 static int __btrfs_grow_device(struct btrfs_trans_handle
*trans
,
1630 struct btrfs_device
*device
, u64 new_size
)
1632 struct btrfs_super_block
*super_copy
=
1633 &device
->dev_root
->fs_info
->super_copy
;
1634 u64 old_total
= btrfs_super_total_bytes(super_copy
);
1635 u64 diff
= new_size
- device
->total_bytes
;
1637 if (!device
->writeable
)
1639 if (new_size
<= device
->total_bytes
)
1642 btrfs_set_super_total_bytes(super_copy
, old_total
+ diff
);
1643 device
->fs_devices
->total_rw_bytes
+= diff
;
1645 device
->total_bytes
= new_size
;
1646 device
->disk_total_bytes
= new_size
;
1647 btrfs_clear_space_info_full(device
->dev_root
->fs_info
);
1649 return btrfs_update_device(trans
, device
);
1652 int btrfs_grow_device(struct btrfs_trans_handle
*trans
,
1653 struct btrfs_device
*device
, u64 new_size
)
1656 lock_chunks(device
->dev_root
);
1657 ret
= __btrfs_grow_device(trans
, device
, new_size
);
1658 unlock_chunks(device
->dev_root
);
1662 static int btrfs_free_chunk(struct btrfs_trans_handle
*trans
,
1663 struct btrfs_root
*root
,
1664 u64 chunk_tree
, u64 chunk_objectid
,
1668 struct btrfs_path
*path
;
1669 struct btrfs_key key
;
1671 root
= root
->fs_info
->chunk_root
;
1672 path
= btrfs_alloc_path();
1676 key
.objectid
= chunk_objectid
;
1677 key
.offset
= chunk_offset
;
1678 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
1680 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1683 ret
= btrfs_del_item(trans
, root
, path
);
1686 btrfs_free_path(path
);
1690 static int btrfs_del_sys_chunk(struct btrfs_root
*root
, u64 chunk_objectid
, u64
1693 struct btrfs_super_block
*super_copy
= &root
->fs_info
->super_copy
;
1694 struct btrfs_disk_key
*disk_key
;
1695 struct btrfs_chunk
*chunk
;
1702 struct btrfs_key key
;
1704 array_size
= btrfs_super_sys_array_size(super_copy
);
1706 ptr
= super_copy
->sys_chunk_array
;
1709 while (cur
< array_size
) {
1710 disk_key
= (struct btrfs_disk_key
*)ptr
;
1711 btrfs_disk_key_to_cpu(&key
, disk_key
);
1713 len
= sizeof(*disk_key
);
1715 if (key
.type
== BTRFS_CHUNK_ITEM_KEY
) {
1716 chunk
= (struct btrfs_chunk
*)(ptr
+ len
);
1717 num_stripes
= btrfs_stack_chunk_num_stripes(chunk
);
1718 len
+= btrfs_chunk_item_size(num_stripes
);
1723 if (key
.objectid
== chunk_objectid
&&
1724 key
.offset
== chunk_offset
) {
1725 memmove(ptr
, ptr
+ len
, array_size
- (cur
+ len
));
1727 btrfs_set_super_sys_array_size(super_copy
, array_size
);
1736 static int btrfs_relocate_chunk(struct btrfs_root
*root
,
1737 u64 chunk_tree
, u64 chunk_objectid
,
1740 struct extent_map_tree
*em_tree
;
1741 struct btrfs_root
*extent_root
;
1742 struct btrfs_trans_handle
*trans
;
1743 struct extent_map
*em
;
1744 struct map_lookup
*map
;
1748 root
= root
->fs_info
->chunk_root
;
1749 extent_root
= root
->fs_info
->extent_root
;
1750 em_tree
= &root
->fs_info
->mapping_tree
.map_tree
;
1752 ret
= btrfs_can_relocate(extent_root
, chunk_offset
);
1756 /* step one, relocate all the extents inside this chunk */
1757 ret
= btrfs_relocate_block_group(extent_root
, chunk_offset
);
1761 trans
= btrfs_start_transaction(root
, 0);
1767 * step two, delete the device extents and the
1768 * chunk tree entries
1770 read_lock(&em_tree
->lock
);
1771 em
= lookup_extent_mapping(em_tree
, chunk_offset
, 1);
1772 read_unlock(&em_tree
->lock
);
1774 BUG_ON(em
->start
> chunk_offset
||
1775 em
->start
+ em
->len
< chunk_offset
);
1776 map
= (struct map_lookup
*)em
->bdev
;
1778 for (i
= 0; i
< map
->num_stripes
; i
++) {
1779 ret
= btrfs_free_dev_extent(trans
, map
->stripes
[i
].dev
,
1780 map
->stripes
[i
].physical
);
1783 if (map
->stripes
[i
].dev
) {
1784 ret
= btrfs_update_device(trans
, map
->stripes
[i
].dev
);
1788 ret
= btrfs_free_chunk(trans
, root
, chunk_tree
, chunk_objectid
,
1793 if (map
->type
& BTRFS_BLOCK_GROUP_SYSTEM
) {
1794 ret
= btrfs_del_sys_chunk(root
, chunk_objectid
, chunk_offset
);
1798 ret
= btrfs_remove_block_group(trans
, extent_root
, chunk_offset
);
1801 write_lock(&em_tree
->lock
);
1802 remove_extent_mapping(em_tree
, em
);
1803 write_unlock(&em_tree
->lock
);
1808 /* once for the tree */
1809 free_extent_map(em
);
1811 free_extent_map(em
);
1813 unlock_chunks(root
);
1814 btrfs_end_transaction(trans
, root
);
1818 static int btrfs_relocate_sys_chunks(struct btrfs_root
*root
)
1820 struct btrfs_root
*chunk_root
= root
->fs_info
->chunk_root
;
1821 struct btrfs_path
*path
;
1822 struct extent_buffer
*leaf
;
1823 struct btrfs_chunk
*chunk
;
1824 struct btrfs_key key
;
1825 struct btrfs_key found_key
;
1826 u64 chunk_tree
= chunk_root
->root_key
.objectid
;
1828 bool retried
= false;
1832 path
= btrfs_alloc_path();
1837 key
.objectid
= BTRFS_FIRST_CHUNK_TREE_OBJECTID
;
1838 key
.offset
= (u64
)-1;
1839 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
1842 ret
= btrfs_search_slot(NULL
, chunk_root
, &key
, path
, 0, 0);
1847 ret
= btrfs_previous_item(chunk_root
, path
, key
.objectid
,
1854 leaf
= path
->nodes
[0];
1855 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
1857 chunk
= btrfs_item_ptr(leaf
, path
->slots
[0],
1858 struct btrfs_chunk
);
1859 chunk_type
= btrfs_chunk_type(leaf
, chunk
);
1860 btrfs_release_path(chunk_root
, path
);
1862 if (chunk_type
& BTRFS_BLOCK_GROUP_SYSTEM
) {
1863 ret
= btrfs_relocate_chunk(chunk_root
, chunk_tree
,
1872 if (found_key
.offset
== 0)
1874 key
.offset
= found_key
.offset
- 1;
1877 if (failed
&& !retried
) {
1881 } else if (failed
&& retried
) {
1886 btrfs_free_path(path
);
1890 static u64
div_factor(u64 num
, int factor
)
1899 int btrfs_balance(struct btrfs_root
*dev_root
)
1902 struct list_head
*devices
= &dev_root
->fs_info
->fs_devices
->devices
;
1903 struct btrfs_device
*device
;
1906 struct btrfs_path
*path
;
1907 struct btrfs_key key
;
1908 struct btrfs_root
*chunk_root
= dev_root
->fs_info
->chunk_root
;
1909 struct btrfs_trans_handle
*trans
;
1910 struct btrfs_key found_key
;
1912 if (dev_root
->fs_info
->sb
->s_flags
& MS_RDONLY
)
1915 mutex_lock(&dev_root
->fs_info
->volume_mutex
);
1916 dev_root
= dev_root
->fs_info
->dev_root
;
1918 /* step one make some room on all the devices */
1919 list_for_each_entry(device
, devices
, dev_list
) {
1920 old_size
= device
->total_bytes
;
1921 size_to_free
= div_factor(old_size
, 1);
1922 size_to_free
= min(size_to_free
, (u64
)1 * 1024 * 1024);
1923 if (!device
->writeable
||
1924 device
->total_bytes
- device
->bytes_used
> size_to_free
)
1927 ret
= btrfs_shrink_device(device
, old_size
- size_to_free
);
1932 trans
= btrfs_start_transaction(dev_root
, 0);
1935 ret
= btrfs_grow_device(trans
, device
, old_size
);
1938 btrfs_end_transaction(trans
, dev_root
);
1941 /* step two, relocate all the chunks */
1942 path
= btrfs_alloc_path();
1945 key
.objectid
= BTRFS_FIRST_CHUNK_TREE_OBJECTID
;
1946 key
.offset
= (u64
)-1;
1947 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
1950 ret
= btrfs_search_slot(NULL
, chunk_root
, &key
, path
, 0, 0);
1955 * this shouldn't happen, it means the last relocate
1961 ret
= btrfs_previous_item(chunk_root
, path
, 0,
1962 BTRFS_CHUNK_ITEM_KEY
);
1966 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
1968 if (found_key
.objectid
!= key
.objectid
)
1971 /* chunk zero is special */
1972 if (found_key
.offset
== 0)
1975 btrfs_release_path(chunk_root
, path
);
1976 ret
= btrfs_relocate_chunk(chunk_root
,
1977 chunk_root
->root_key
.objectid
,
1980 BUG_ON(ret
&& ret
!= -ENOSPC
);
1981 key
.offset
= found_key
.offset
- 1;
1985 btrfs_free_path(path
);
1986 mutex_unlock(&dev_root
->fs_info
->volume_mutex
);
1991 * shrinking a device means finding all of the device extents past
1992 * the new size, and then following the back refs to the chunks.
1993 * The chunk relocation code actually frees the device extent
1995 int btrfs_shrink_device(struct btrfs_device
*device
, u64 new_size
)
1997 struct btrfs_trans_handle
*trans
;
1998 struct btrfs_root
*root
= device
->dev_root
;
1999 struct btrfs_dev_extent
*dev_extent
= NULL
;
2000 struct btrfs_path
*path
;
2008 bool retried
= false;
2009 struct extent_buffer
*l
;
2010 struct btrfs_key key
;
2011 struct btrfs_super_block
*super_copy
= &root
->fs_info
->super_copy
;
2012 u64 old_total
= btrfs_super_total_bytes(super_copy
);
2013 u64 old_size
= device
->total_bytes
;
2014 u64 diff
= device
->total_bytes
- new_size
;
2016 if (new_size
>= device
->total_bytes
)
2019 path
= btrfs_alloc_path();
2027 device
->total_bytes
= new_size
;
2028 if (device
->writeable
)
2029 device
->fs_devices
->total_rw_bytes
-= diff
;
2030 unlock_chunks(root
);
2033 key
.objectid
= device
->devid
;
2034 key
.offset
= (u64
)-1;
2035 key
.type
= BTRFS_DEV_EXTENT_KEY
;
2038 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
2042 ret
= btrfs_previous_item(root
, path
, 0, key
.type
);
2047 btrfs_release_path(root
, path
);
2052 slot
= path
->slots
[0];
2053 btrfs_item_key_to_cpu(l
, &key
, path
->slots
[0]);
2055 if (key
.objectid
!= device
->devid
) {
2056 btrfs_release_path(root
, path
);
2060 dev_extent
= btrfs_item_ptr(l
, slot
, struct btrfs_dev_extent
);
2061 length
= btrfs_dev_extent_length(l
, dev_extent
);
2063 if (key
.offset
+ length
<= new_size
) {
2064 btrfs_release_path(root
, path
);
2068 chunk_tree
= btrfs_dev_extent_chunk_tree(l
, dev_extent
);
2069 chunk_objectid
= btrfs_dev_extent_chunk_objectid(l
, dev_extent
);
2070 chunk_offset
= btrfs_dev_extent_chunk_offset(l
, dev_extent
);
2071 btrfs_release_path(root
, path
);
2073 ret
= btrfs_relocate_chunk(root
, chunk_tree
, chunk_objectid
,
2075 if (ret
&& ret
!= -ENOSPC
)
2082 if (failed
&& !retried
) {
2086 } else if (failed
&& retried
) {
2090 device
->total_bytes
= old_size
;
2091 if (device
->writeable
)
2092 device
->fs_devices
->total_rw_bytes
+= diff
;
2093 unlock_chunks(root
);
2097 /* Shrinking succeeded, else we would be at "done". */
2098 trans
= btrfs_start_transaction(root
, 0);
2101 device
->disk_total_bytes
= new_size
;
2102 /* Now btrfs_update_device() will change the on-disk size. */
2103 ret
= btrfs_update_device(trans
, device
);
2105 unlock_chunks(root
);
2106 btrfs_end_transaction(trans
, root
);
2109 WARN_ON(diff
> old_total
);
2110 btrfs_set_super_total_bytes(super_copy
, old_total
- diff
);
2111 unlock_chunks(root
);
2112 btrfs_end_transaction(trans
, root
);
2114 btrfs_free_path(path
);
2118 static int btrfs_add_system_chunk(struct btrfs_trans_handle
*trans
,
2119 struct btrfs_root
*root
,
2120 struct btrfs_key
*key
,
2121 struct btrfs_chunk
*chunk
, int item_size
)
2123 struct btrfs_super_block
*super_copy
= &root
->fs_info
->super_copy
;
2124 struct btrfs_disk_key disk_key
;
2128 array_size
= btrfs_super_sys_array_size(super_copy
);
2129 if (array_size
+ item_size
> BTRFS_SYSTEM_CHUNK_ARRAY_SIZE
)
2132 ptr
= super_copy
->sys_chunk_array
+ array_size
;
2133 btrfs_cpu_key_to_disk(&disk_key
, key
);
2134 memcpy(ptr
, &disk_key
, sizeof(disk_key
));
2135 ptr
+= sizeof(disk_key
);
2136 memcpy(ptr
, chunk
, item_size
);
2137 item_size
+= sizeof(disk_key
);
2138 btrfs_set_super_sys_array_size(super_copy
, array_size
+ item_size
);
2142 static noinline u64
chunk_bytes_by_type(u64 type
, u64 calc_size
,
2143 int num_stripes
, int sub_stripes
)
2145 if (type
& (BTRFS_BLOCK_GROUP_RAID1
| BTRFS_BLOCK_GROUP_DUP
))
2147 else if (type
& BTRFS_BLOCK_GROUP_RAID10
)
2148 return calc_size
* (num_stripes
/ sub_stripes
);
2150 return calc_size
* num_stripes
;
2153 static int __btrfs_alloc_chunk(struct btrfs_trans_handle
*trans
,
2154 struct btrfs_root
*extent_root
,
2155 struct map_lookup
**map_ret
,
2156 u64
*num_bytes
, u64
*stripe_size
,
2157 u64 start
, u64 type
)
2159 struct btrfs_fs_info
*info
= extent_root
->fs_info
;
2160 struct btrfs_device
*device
= NULL
;
2161 struct btrfs_fs_devices
*fs_devices
= info
->fs_devices
;
2162 struct list_head
*cur
;
2163 struct map_lookup
*map
= NULL
;
2164 struct extent_map_tree
*em_tree
;
2165 struct extent_map
*em
;
2166 struct list_head private_devs
;
2167 int min_stripe_size
= 1 * 1024 * 1024;
2168 u64 calc_size
= 1024 * 1024 * 1024;
2169 u64 max_chunk_size
= calc_size
;
2174 int num_stripes
= 1;
2175 int min_stripes
= 1;
2176 int sub_stripes
= 0;
2180 int stripe_len
= 64 * 1024;
2182 if ((type
& BTRFS_BLOCK_GROUP_RAID1
) &&
2183 (type
& BTRFS_BLOCK_GROUP_DUP
)) {
2185 type
&= ~BTRFS_BLOCK_GROUP_DUP
;
2187 if (list_empty(&fs_devices
->alloc_list
))
2190 if (type
& (BTRFS_BLOCK_GROUP_RAID0
)) {
2191 num_stripes
= fs_devices
->rw_devices
;
2194 if (type
& (BTRFS_BLOCK_GROUP_DUP
)) {
2198 if (type
& (BTRFS_BLOCK_GROUP_RAID1
)) {
2199 if (fs_devices
->rw_devices
< 2)
2204 if (type
& (BTRFS_BLOCK_GROUP_RAID10
)) {
2205 num_stripes
= fs_devices
->rw_devices
;
2206 if (num_stripes
< 4)
2208 num_stripes
&= ~(u32
)1;
2213 if (type
& BTRFS_BLOCK_GROUP_DATA
) {
2214 max_chunk_size
= 10 * calc_size
;
2215 min_stripe_size
= 64 * 1024 * 1024;
2216 } else if (type
& BTRFS_BLOCK_GROUP_METADATA
) {
2217 max_chunk_size
= 256 * 1024 * 1024;
2218 min_stripe_size
= 32 * 1024 * 1024;
2219 } else if (type
& BTRFS_BLOCK_GROUP_SYSTEM
) {
2220 calc_size
= 8 * 1024 * 1024;
2221 max_chunk_size
= calc_size
* 2;
2222 min_stripe_size
= 1 * 1024 * 1024;
2225 /* we don't want a chunk larger than 10% of writeable space */
2226 max_chunk_size
= min(div_factor(fs_devices
->total_rw_bytes
, 1),
2231 if (!map
|| map
->num_stripes
!= num_stripes
) {
2233 map
= kmalloc(map_lookup_size(num_stripes
), GFP_NOFS
);
2236 map
->num_stripes
= num_stripes
;
2239 if (calc_size
* num_stripes
> max_chunk_size
) {
2240 calc_size
= max_chunk_size
;
2241 do_div(calc_size
, num_stripes
);
2242 do_div(calc_size
, stripe_len
);
2243 calc_size
*= stripe_len
;
2246 /* we don't want tiny stripes */
2248 calc_size
= max_t(u64
, min_stripe_size
, calc_size
);
2251 * we're about to do_div by the stripe_len so lets make sure
2252 * we end up with something bigger than a stripe
2254 calc_size
= max_t(u64
, calc_size
, stripe_len
* 4);
2256 do_div(calc_size
, stripe_len
);
2257 calc_size
*= stripe_len
;
2259 cur
= fs_devices
->alloc_list
.next
;
2262 if (type
& BTRFS_BLOCK_GROUP_DUP
)
2263 min_free
= calc_size
* 2;
2265 min_free
= calc_size
;
2268 * we add 1MB because we never use the first 1MB of the device, unless
2269 * we've looped, then we are likely allocating the maximum amount of
2270 * space left already
2273 min_free
+= 1024 * 1024;
2275 INIT_LIST_HEAD(&private_devs
);
2276 while (index
< num_stripes
) {
2277 device
= list_entry(cur
, struct btrfs_device
, dev_alloc_list
);
2278 BUG_ON(!device
->writeable
);
2279 if (device
->total_bytes
> device
->bytes_used
)
2280 avail
= device
->total_bytes
- device
->bytes_used
;
2285 if (device
->in_fs_metadata
&& avail
>= min_free
) {
2286 ret
= find_free_dev_extent(trans
, device
,
2287 min_free
, &dev_offset
,
2290 list_move_tail(&device
->dev_alloc_list
,
2292 map
->stripes
[index
].dev
= device
;
2293 map
->stripes
[index
].physical
= dev_offset
;
2295 if (type
& BTRFS_BLOCK_GROUP_DUP
) {
2296 map
->stripes
[index
].dev
= device
;
2297 map
->stripes
[index
].physical
=
2298 dev_offset
+ calc_size
;
2302 } else if (device
->in_fs_metadata
&& avail
> max_avail
)
2304 if (cur
== &fs_devices
->alloc_list
)
2307 list_splice(&private_devs
, &fs_devices
->alloc_list
);
2308 if (index
< num_stripes
) {
2309 if (index
>= min_stripes
) {
2310 num_stripes
= index
;
2311 if (type
& (BTRFS_BLOCK_GROUP_RAID10
)) {
2312 num_stripes
/= sub_stripes
;
2313 num_stripes
*= sub_stripes
;
2318 if (!looped
&& max_avail
> 0) {
2320 calc_size
= max_avail
;
2326 map
->sector_size
= extent_root
->sectorsize
;
2327 map
->stripe_len
= stripe_len
;
2328 map
->io_align
= stripe_len
;
2329 map
->io_width
= stripe_len
;
2331 map
->num_stripes
= num_stripes
;
2332 map
->sub_stripes
= sub_stripes
;
2335 *stripe_size
= calc_size
;
2336 *num_bytes
= chunk_bytes_by_type(type
, calc_size
,
2337 num_stripes
, sub_stripes
);
2339 em
= alloc_extent_map(GFP_NOFS
);
2344 em
->bdev
= (struct block_device
*)map
;
2346 em
->len
= *num_bytes
;
2347 em
->block_start
= 0;
2348 em
->block_len
= em
->len
;
2350 em_tree
= &extent_root
->fs_info
->mapping_tree
.map_tree
;
2351 write_lock(&em_tree
->lock
);
2352 ret
= add_extent_mapping(em_tree
, em
);
2353 write_unlock(&em_tree
->lock
);
2355 free_extent_map(em
);
2357 ret
= btrfs_make_block_group(trans
, extent_root
, 0, type
,
2358 BTRFS_FIRST_CHUNK_TREE_OBJECTID
,
2363 while (index
< map
->num_stripes
) {
2364 device
= map
->stripes
[index
].dev
;
2365 dev_offset
= map
->stripes
[index
].physical
;
2367 ret
= btrfs_alloc_dev_extent(trans
, device
,
2368 info
->chunk_root
->root_key
.objectid
,
2369 BTRFS_FIRST_CHUNK_TREE_OBJECTID
,
2370 start
, dev_offset
, calc_size
);
2378 static int __finish_chunk_alloc(struct btrfs_trans_handle
*trans
,
2379 struct btrfs_root
*extent_root
,
2380 struct map_lookup
*map
, u64 chunk_offset
,
2381 u64 chunk_size
, u64 stripe_size
)
2384 struct btrfs_key key
;
2385 struct btrfs_root
*chunk_root
= extent_root
->fs_info
->chunk_root
;
2386 struct btrfs_device
*device
;
2387 struct btrfs_chunk
*chunk
;
2388 struct btrfs_stripe
*stripe
;
2389 size_t item_size
= btrfs_chunk_item_size(map
->num_stripes
);
2393 chunk
= kzalloc(item_size
, GFP_NOFS
);
2398 while (index
< map
->num_stripes
) {
2399 device
= map
->stripes
[index
].dev
;
2400 device
->bytes_used
+= stripe_size
;
2401 ret
= btrfs_update_device(trans
, device
);
2407 stripe
= &chunk
->stripe
;
2408 while (index
< map
->num_stripes
) {
2409 device
= map
->stripes
[index
].dev
;
2410 dev_offset
= map
->stripes
[index
].physical
;
2412 btrfs_set_stack_stripe_devid(stripe
, device
->devid
);
2413 btrfs_set_stack_stripe_offset(stripe
, dev_offset
);
2414 memcpy(stripe
->dev_uuid
, device
->uuid
, BTRFS_UUID_SIZE
);
2419 btrfs_set_stack_chunk_length(chunk
, chunk_size
);
2420 btrfs_set_stack_chunk_owner(chunk
, extent_root
->root_key
.objectid
);
2421 btrfs_set_stack_chunk_stripe_len(chunk
, map
->stripe_len
);
2422 btrfs_set_stack_chunk_type(chunk
, map
->type
);
2423 btrfs_set_stack_chunk_num_stripes(chunk
, map
->num_stripes
);
2424 btrfs_set_stack_chunk_io_align(chunk
, map
->stripe_len
);
2425 btrfs_set_stack_chunk_io_width(chunk
, map
->stripe_len
);
2426 btrfs_set_stack_chunk_sector_size(chunk
, extent_root
->sectorsize
);
2427 btrfs_set_stack_chunk_sub_stripes(chunk
, map
->sub_stripes
);
2429 key
.objectid
= BTRFS_FIRST_CHUNK_TREE_OBJECTID
;
2430 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
2431 key
.offset
= chunk_offset
;
2433 ret
= btrfs_insert_item(trans
, chunk_root
, &key
, chunk
, item_size
);
2436 if (map
->type
& BTRFS_BLOCK_GROUP_SYSTEM
) {
2437 ret
= btrfs_add_system_chunk(trans
, chunk_root
, &key
, chunk
,
2446 * Chunk allocation falls into two parts. The first part does works
2447 * that make the new allocated chunk useable, but not do any operation
2448 * that modifies the chunk tree. The second part does the works that
2449 * require modifying the chunk tree. This division is important for the
2450 * bootstrap process of adding storage to a seed btrfs.
2452 int btrfs_alloc_chunk(struct btrfs_trans_handle
*trans
,
2453 struct btrfs_root
*extent_root
, u64 type
)
2458 struct map_lookup
*map
;
2459 struct btrfs_root
*chunk_root
= extent_root
->fs_info
->chunk_root
;
2462 ret
= find_next_chunk(chunk_root
, BTRFS_FIRST_CHUNK_TREE_OBJECTID
,
2467 ret
= __btrfs_alloc_chunk(trans
, extent_root
, &map
, &chunk_size
,
2468 &stripe_size
, chunk_offset
, type
);
2472 ret
= __finish_chunk_alloc(trans
, extent_root
, map
, chunk_offset
,
2473 chunk_size
, stripe_size
);
2478 static noinline
int init_first_rw_device(struct btrfs_trans_handle
*trans
,
2479 struct btrfs_root
*root
,
2480 struct btrfs_device
*device
)
2483 u64 sys_chunk_offset
;
2487 u64 sys_stripe_size
;
2489 struct map_lookup
*map
;
2490 struct map_lookup
*sys_map
;
2491 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2492 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
2495 ret
= find_next_chunk(fs_info
->chunk_root
,
2496 BTRFS_FIRST_CHUNK_TREE_OBJECTID
, &chunk_offset
);
2499 alloc_profile
= BTRFS_BLOCK_GROUP_METADATA
|
2500 (fs_info
->metadata_alloc_profile
&
2501 fs_info
->avail_metadata_alloc_bits
);
2502 alloc_profile
= btrfs_reduce_alloc_profile(root
, alloc_profile
);
2504 ret
= __btrfs_alloc_chunk(trans
, extent_root
, &map
, &chunk_size
,
2505 &stripe_size
, chunk_offset
, alloc_profile
);
2508 sys_chunk_offset
= chunk_offset
+ chunk_size
;
2510 alloc_profile
= BTRFS_BLOCK_GROUP_SYSTEM
|
2511 (fs_info
->system_alloc_profile
&
2512 fs_info
->avail_system_alloc_bits
);
2513 alloc_profile
= btrfs_reduce_alloc_profile(root
, alloc_profile
);
2515 ret
= __btrfs_alloc_chunk(trans
, extent_root
, &sys_map
,
2516 &sys_chunk_size
, &sys_stripe_size
,
2517 sys_chunk_offset
, alloc_profile
);
2520 ret
= btrfs_add_device(trans
, fs_info
->chunk_root
, device
);
2524 * Modifying chunk tree needs allocating new blocks from both
2525 * system block group and metadata block group. So we only can
2526 * do operations require modifying the chunk tree after both
2527 * block groups were created.
2529 ret
= __finish_chunk_alloc(trans
, extent_root
, map
, chunk_offset
,
2530 chunk_size
, stripe_size
);
2533 ret
= __finish_chunk_alloc(trans
, extent_root
, sys_map
,
2534 sys_chunk_offset
, sys_chunk_size
,
2540 int btrfs_chunk_readonly(struct btrfs_root
*root
, u64 chunk_offset
)
2542 struct extent_map
*em
;
2543 struct map_lookup
*map
;
2544 struct btrfs_mapping_tree
*map_tree
= &root
->fs_info
->mapping_tree
;
2548 read_lock(&map_tree
->map_tree
.lock
);
2549 em
= lookup_extent_mapping(&map_tree
->map_tree
, chunk_offset
, 1);
2550 read_unlock(&map_tree
->map_tree
.lock
);
2554 if (btrfs_test_opt(root
, DEGRADED
)) {
2555 free_extent_map(em
);
2559 map
= (struct map_lookup
*)em
->bdev
;
2560 for (i
= 0; i
< map
->num_stripes
; i
++) {
2561 if (!map
->stripes
[i
].dev
->writeable
) {
2566 free_extent_map(em
);
2570 void btrfs_mapping_init(struct btrfs_mapping_tree
*tree
)
2572 extent_map_tree_init(&tree
->map_tree
, GFP_NOFS
);
2575 void btrfs_mapping_tree_free(struct btrfs_mapping_tree
*tree
)
2577 struct extent_map
*em
;
2580 write_lock(&tree
->map_tree
.lock
);
2581 em
= lookup_extent_mapping(&tree
->map_tree
, 0, (u64
)-1);
2583 remove_extent_mapping(&tree
->map_tree
, em
);
2584 write_unlock(&tree
->map_tree
.lock
);
2589 free_extent_map(em
);
2590 /* once for the tree */
2591 free_extent_map(em
);
2595 int btrfs_num_copies(struct btrfs_mapping_tree
*map_tree
, u64 logical
, u64 len
)
2597 struct extent_map
*em
;
2598 struct map_lookup
*map
;
2599 struct extent_map_tree
*em_tree
= &map_tree
->map_tree
;
2602 read_lock(&em_tree
->lock
);
2603 em
= lookup_extent_mapping(em_tree
, logical
, len
);
2604 read_unlock(&em_tree
->lock
);
2607 BUG_ON(em
->start
> logical
|| em
->start
+ em
->len
< logical
);
2608 map
= (struct map_lookup
*)em
->bdev
;
2609 if (map
->type
& (BTRFS_BLOCK_GROUP_DUP
| BTRFS_BLOCK_GROUP_RAID1
))
2610 ret
= map
->num_stripes
;
2611 else if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
)
2612 ret
= map
->sub_stripes
;
2615 free_extent_map(em
);
2619 static int find_live_mirror(struct map_lookup
*map
, int first
, int num
,
2623 if (map
->stripes
[optimal
].dev
->bdev
)
2625 for (i
= first
; i
< first
+ num
; i
++) {
2626 if (map
->stripes
[i
].dev
->bdev
)
2629 /* we couldn't find one that doesn't fail. Just return something
2630 * and the io error handling code will clean up eventually
2635 static int __btrfs_map_block(struct btrfs_mapping_tree
*map_tree
, int rw
,
2636 u64 logical
, u64
*length
,
2637 struct btrfs_multi_bio
**multi_ret
,
2638 int mirror_num
, struct page
*unplug_page
)
2640 struct extent_map
*em
;
2641 struct map_lookup
*map
;
2642 struct extent_map_tree
*em_tree
= &map_tree
->map_tree
;
2646 int stripes_allocated
= 8;
2647 int stripes_required
= 1;
2652 struct btrfs_multi_bio
*multi
= NULL
;
2654 if (multi_ret
&& !(rw
& REQ_WRITE
))
2655 stripes_allocated
= 1;
2658 multi
= kzalloc(btrfs_multi_bio_size(stripes_allocated
),
2663 atomic_set(&multi
->error
, 0);
2666 read_lock(&em_tree
->lock
);
2667 em
= lookup_extent_mapping(em_tree
, logical
, *length
);
2668 read_unlock(&em_tree
->lock
);
2670 if (!em
&& unplug_page
) {
2676 printk(KERN_CRIT
"unable to find logical %llu len %llu\n",
2677 (unsigned long long)logical
,
2678 (unsigned long long)*length
);
2682 BUG_ON(em
->start
> logical
|| em
->start
+ em
->len
< logical
);
2683 map
= (struct map_lookup
*)em
->bdev
;
2684 offset
= logical
- em
->start
;
2686 if (mirror_num
> map
->num_stripes
)
2689 /* if our multi bio struct is too small, back off and try again */
2690 if (rw
& REQ_WRITE
) {
2691 if (map
->type
& (BTRFS_BLOCK_GROUP_RAID1
|
2692 BTRFS_BLOCK_GROUP_DUP
)) {
2693 stripes_required
= map
->num_stripes
;
2695 } else if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
) {
2696 stripes_required
= map
->sub_stripes
;
2700 if (multi_ret
&& (rw
& REQ_WRITE
) &&
2701 stripes_allocated
< stripes_required
) {
2702 stripes_allocated
= map
->num_stripes
;
2703 free_extent_map(em
);
2709 * stripe_nr counts the total number of stripes we have to stride
2710 * to get to this block
2712 do_div(stripe_nr
, map
->stripe_len
);
2714 stripe_offset
= stripe_nr
* map
->stripe_len
;
2715 BUG_ON(offset
< stripe_offset
);
2717 /* stripe_offset is the offset of this block in its stripe*/
2718 stripe_offset
= offset
- stripe_offset
;
2720 if (map
->type
& (BTRFS_BLOCK_GROUP_RAID0
| BTRFS_BLOCK_GROUP_RAID1
|
2721 BTRFS_BLOCK_GROUP_RAID10
|
2722 BTRFS_BLOCK_GROUP_DUP
)) {
2723 /* we limit the length of each bio to what fits in a stripe */
2724 *length
= min_t(u64
, em
->len
- offset
,
2725 map
->stripe_len
- stripe_offset
);
2727 *length
= em
->len
- offset
;
2730 if (!multi_ret
&& !unplug_page
)
2735 if (map
->type
& BTRFS_BLOCK_GROUP_RAID1
) {
2736 if (unplug_page
|| (rw
& REQ_WRITE
))
2737 num_stripes
= map
->num_stripes
;
2738 else if (mirror_num
)
2739 stripe_index
= mirror_num
- 1;
2741 stripe_index
= find_live_mirror(map
, 0,
2743 current
->pid
% map
->num_stripes
);
2746 } else if (map
->type
& BTRFS_BLOCK_GROUP_DUP
) {
2748 num_stripes
= map
->num_stripes
;
2749 else if (mirror_num
)
2750 stripe_index
= mirror_num
- 1;
2752 } else if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
) {
2753 int factor
= map
->num_stripes
/ map
->sub_stripes
;
2755 stripe_index
= do_div(stripe_nr
, factor
);
2756 stripe_index
*= map
->sub_stripes
;
2758 if (unplug_page
|| (rw
& REQ_WRITE
))
2759 num_stripes
= map
->sub_stripes
;
2760 else if (mirror_num
)
2761 stripe_index
+= mirror_num
- 1;
2763 stripe_index
= find_live_mirror(map
, stripe_index
,
2764 map
->sub_stripes
, stripe_index
+
2765 current
->pid
% map
->sub_stripes
);
2769 * after this do_div call, stripe_nr is the number of stripes
2770 * on this device we have to walk to find the data, and
2771 * stripe_index is the number of our device in the stripe array
2773 stripe_index
= do_div(stripe_nr
, map
->num_stripes
);
2775 BUG_ON(stripe_index
>= map
->num_stripes
);
2777 for (i
= 0; i
< num_stripes
; i
++) {
2779 struct btrfs_device
*device
;
2780 struct backing_dev_info
*bdi
;
2782 device
= map
->stripes
[stripe_index
].dev
;
2784 bdi
= blk_get_backing_dev_info(device
->bdev
);
2785 if (bdi
->unplug_io_fn
)
2786 bdi
->unplug_io_fn(bdi
, unplug_page
);
2789 multi
->stripes
[i
].physical
=
2790 map
->stripes
[stripe_index
].physical
+
2791 stripe_offset
+ stripe_nr
* map
->stripe_len
;
2792 multi
->stripes
[i
].dev
= map
->stripes
[stripe_index
].dev
;
2798 multi
->num_stripes
= num_stripes
;
2799 multi
->max_errors
= max_errors
;
2802 free_extent_map(em
);
2806 int btrfs_map_block(struct btrfs_mapping_tree
*map_tree
, int rw
,
2807 u64 logical
, u64
*length
,
2808 struct btrfs_multi_bio
**multi_ret
, int mirror_num
)
2810 return __btrfs_map_block(map_tree
, rw
, logical
, length
, multi_ret
,
2814 int btrfs_rmap_block(struct btrfs_mapping_tree
*map_tree
,
2815 u64 chunk_start
, u64 physical
, u64 devid
,
2816 u64
**logical
, int *naddrs
, int *stripe_len
)
2818 struct extent_map_tree
*em_tree
= &map_tree
->map_tree
;
2819 struct extent_map
*em
;
2820 struct map_lookup
*map
;
2827 read_lock(&em_tree
->lock
);
2828 em
= lookup_extent_mapping(em_tree
, chunk_start
, 1);
2829 read_unlock(&em_tree
->lock
);
2831 BUG_ON(!em
|| em
->start
!= chunk_start
);
2832 map
= (struct map_lookup
*)em
->bdev
;
2835 if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
)
2836 do_div(length
, map
->num_stripes
/ map
->sub_stripes
);
2837 else if (map
->type
& BTRFS_BLOCK_GROUP_RAID0
)
2838 do_div(length
, map
->num_stripes
);
2840 buf
= kzalloc(sizeof(u64
) * map
->num_stripes
, GFP_NOFS
);
2843 for (i
= 0; i
< map
->num_stripes
; i
++) {
2844 if (devid
&& map
->stripes
[i
].dev
->devid
!= devid
)
2846 if (map
->stripes
[i
].physical
> physical
||
2847 map
->stripes
[i
].physical
+ length
<= physical
)
2850 stripe_nr
= physical
- map
->stripes
[i
].physical
;
2851 do_div(stripe_nr
, map
->stripe_len
);
2853 if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
) {
2854 stripe_nr
= stripe_nr
* map
->num_stripes
+ i
;
2855 do_div(stripe_nr
, map
->sub_stripes
);
2856 } else if (map
->type
& BTRFS_BLOCK_GROUP_RAID0
) {
2857 stripe_nr
= stripe_nr
* map
->num_stripes
+ i
;
2859 bytenr
= chunk_start
+ stripe_nr
* map
->stripe_len
;
2860 WARN_ON(nr
>= map
->num_stripes
);
2861 for (j
= 0; j
< nr
; j
++) {
2862 if (buf
[j
] == bytenr
)
2866 WARN_ON(nr
>= map
->num_stripes
);
2873 *stripe_len
= map
->stripe_len
;
2875 free_extent_map(em
);
2879 int btrfs_unplug_page(struct btrfs_mapping_tree
*map_tree
,
2880 u64 logical
, struct page
*page
)
2882 u64 length
= PAGE_CACHE_SIZE
;
2883 return __btrfs_map_block(map_tree
, READ
, logical
, &length
,
2887 static void end_bio_multi_stripe(struct bio
*bio
, int err
)
2889 struct btrfs_multi_bio
*multi
= bio
->bi_private
;
2890 int is_orig_bio
= 0;
2893 atomic_inc(&multi
->error
);
2895 if (bio
== multi
->orig_bio
)
2898 if (atomic_dec_and_test(&multi
->stripes_pending
)) {
2901 bio
= multi
->orig_bio
;
2903 bio
->bi_private
= multi
->private;
2904 bio
->bi_end_io
= multi
->end_io
;
2905 /* only send an error to the higher layers if it is
2906 * beyond the tolerance of the multi-bio
2908 if (atomic_read(&multi
->error
) > multi
->max_errors
) {
2912 * this bio is actually up to date, we didn't
2913 * go over the max number of errors
2915 set_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2920 bio_endio(bio
, err
);
2921 } else if (!is_orig_bio
) {
2926 struct async_sched
{
2929 struct btrfs_fs_info
*info
;
2930 struct btrfs_work work
;
2934 * see run_scheduled_bios for a description of why bios are collected for
2937 * This will add one bio to the pending list for a device and make sure
2938 * the work struct is scheduled.
2940 static noinline
int schedule_bio(struct btrfs_root
*root
,
2941 struct btrfs_device
*device
,
2942 int rw
, struct bio
*bio
)
2944 int should_queue
= 1;
2945 struct btrfs_pending_bios
*pending_bios
;
2947 /* don't bother with additional async steps for reads, right now */
2948 if (!(rw
& REQ_WRITE
)) {
2950 submit_bio(rw
, bio
);
2956 * nr_async_bios allows us to reliably return congestion to the
2957 * higher layers. Otherwise, the async bio makes it appear we have
2958 * made progress against dirty pages when we've really just put it
2959 * on a queue for later
2961 atomic_inc(&root
->fs_info
->nr_async_bios
);
2962 WARN_ON(bio
->bi_next
);
2963 bio
->bi_next
= NULL
;
2966 spin_lock(&device
->io_lock
);
2967 if (bio
->bi_rw
& REQ_SYNC
)
2968 pending_bios
= &device
->pending_sync_bios
;
2970 pending_bios
= &device
->pending_bios
;
2972 if (pending_bios
->tail
)
2973 pending_bios
->tail
->bi_next
= bio
;
2975 pending_bios
->tail
= bio
;
2976 if (!pending_bios
->head
)
2977 pending_bios
->head
= bio
;
2978 if (device
->running_pending
)
2981 spin_unlock(&device
->io_lock
);
2984 btrfs_queue_worker(&root
->fs_info
->submit_workers
,
2989 int btrfs_map_bio(struct btrfs_root
*root
, int rw
, struct bio
*bio
,
2990 int mirror_num
, int async_submit
)
2992 struct btrfs_mapping_tree
*map_tree
;
2993 struct btrfs_device
*dev
;
2994 struct bio
*first_bio
= bio
;
2995 u64 logical
= (u64
)bio
->bi_sector
<< 9;
2998 struct btrfs_multi_bio
*multi
= NULL
;
3003 length
= bio
->bi_size
;
3004 map_tree
= &root
->fs_info
->mapping_tree
;
3005 map_length
= length
;
3007 ret
= btrfs_map_block(map_tree
, rw
, logical
, &map_length
, &multi
,
3011 total_devs
= multi
->num_stripes
;
3012 if (map_length
< length
) {
3013 printk(KERN_CRIT
"mapping failed logical %llu bio len %llu "
3014 "len %llu\n", (unsigned long long)logical
,
3015 (unsigned long long)length
,
3016 (unsigned long long)map_length
);
3019 multi
->end_io
= first_bio
->bi_end_io
;
3020 multi
->private = first_bio
->bi_private
;
3021 multi
->orig_bio
= first_bio
;
3022 atomic_set(&multi
->stripes_pending
, multi
->num_stripes
);
3024 while (dev_nr
< total_devs
) {
3025 if (total_devs
> 1) {
3026 if (dev_nr
< total_devs
- 1) {
3027 bio
= bio_clone(first_bio
, GFP_NOFS
);
3032 bio
->bi_private
= multi
;
3033 bio
->bi_end_io
= end_bio_multi_stripe
;
3035 bio
->bi_sector
= multi
->stripes
[dev_nr
].physical
>> 9;
3036 dev
= multi
->stripes
[dev_nr
].dev
;
3037 if (dev
&& dev
->bdev
&& (rw
!= WRITE
|| dev
->writeable
)) {
3038 bio
->bi_bdev
= dev
->bdev
;
3040 schedule_bio(root
, dev
, rw
, bio
);
3042 submit_bio(rw
, bio
);
3044 bio
->bi_bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
3045 bio
->bi_sector
= logical
>> 9;
3046 bio_endio(bio
, -EIO
);
3050 if (total_devs
== 1)
3055 struct btrfs_device
*btrfs_find_device(struct btrfs_root
*root
, u64 devid
,
3058 struct btrfs_device
*device
;
3059 struct btrfs_fs_devices
*cur_devices
;
3061 cur_devices
= root
->fs_info
->fs_devices
;
3062 while (cur_devices
) {
3064 !memcmp(cur_devices
->fsid
, fsid
, BTRFS_UUID_SIZE
)) {
3065 device
= __find_device(&cur_devices
->devices
,
3070 cur_devices
= cur_devices
->seed
;
3075 static struct btrfs_device
*add_missing_dev(struct btrfs_root
*root
,
3076 u64 devid
, u8
*dev_uuid
)
3078 struct btrfs_device
*device
;
3079 struct btrfs_fs_devices
*fs_devices
= root
->fs_info
->fs_devices
;
3081 device
= kzalloc(sizeof(*device
), GFP_NOFS
);
3084 list_add(&device
->dev_list
,
3085 &fs_devices
->devices
);
3086 device
->dev_root
= root
->fs_info
->dev_root
;
3087 device
->devid
= devid
;
3088 device
->work
.func
= pending_bios_fn
;
3089 device
->fs_devices
= fs_devices
;
3090 device
->missing
= 1;
3091 fs_devices
->num_devices
++;
3092 fs_devices
->missing_devices
++;
3093 spin_lock_init(&device
->io_lock
);
3094 INIT_LIST_HEAD(&device
->dev_alloc_list
);
3095 memcpy(device
->uuid
, dev_uuid
, BTRFS_UUID_SIZE
);
3099 static int read_one_chunk(struct btrfs_root
*root
, struct btrfs_key
*key
,
3100 struct extent_buffer
*leaf
,
3101 struct btrfs_chunk
*chunk
)
3103 struct btrfs_mapping_tree
*map_tree
= &root
->fs_info
->mapping_tree
;
3104 struct map_lookup
*map
;
3105 struct extent_map
*em
;
3109 u8 uuid
[BTRFS_UUID_SIZE
];
3114 logical
= key
->offset
;
3115 length
= btrfs_chunk_length(leaf
, chunk
);
3117 read_lock(&map_tree
->map_tree
.lock
);
3118 em
= lookup_extent_mapping(&map_tree
->map_tree
, logical
, 1);
3119 read_unlock(&map_tree
->map_tree
.lock
);
3121 /* already mapped? */
3122 if (em
&& em
->start
<= logical
&& em
->start
+ em
->len
> logical
) {
3123 free_extent_map(em
);
3126 free_extent_map(em
);
3129 em
= alloc_extent_map(GFP_NOFS
);
3132 num_stripes
= btrfs_chunk_num_stripes(leaf
, chunk
);
3133 map
= kmalloc(map_lookup_size(num_stripes
), GFP_NOFS
);
3135 free_extent_map(em
);
3139 em
->bdev
= (struct block_device
*)map
;
3140 em
->start
= logical
;
3142 em
->block_start
= 0;
3143 em
->block_len
= em
->len
;
3145 map
->num_stripes
= num_stripes
;
3146 map
->io_width
= btrfs_chunk_io_width(leaf
, chunk
);
3147 map
->io_align
= btrfs_chunk_io_align(leaf
, chunk
);
3148 map
->sector_size
= btrfs_chunk_sector_size(leaf
, chunk
);
3149 map
->stripe_len
= btrfs_chunk_stripe_len(leaf
, chunk
);
3150 map
->type
= btrfs_chunk_type(leaf
, chunk
);
3151 map
->sub_stripes
= btrfs_chunk_sub_stripes(leaf
, chunk
);
3152 for (i
= 0; i
< num_stripes
; i
++) {
3153 map
->stripes
[i
].physical
=
3154 btrfs_stripe_offset_nr(leaf
, chunk
, i
);
3155 devid
= btrfs_stripe_devid_nr(leaf
, chunk
, i
);
3156 read_extent_buffer(leaf
, uuid
, (unsigned long)
3157 btrfs_stripe_dev_uuid_nr(chunk
, i
),
3159 map
->stripes
[i
].dev
= btrfs_find_device(root
, devid
, uuid
,
3161 if (!map
->stripes
[i
].dev
&& !btrfs_test_opt(root
, DEGRADED
)) {
3163 free_extent_map(em
);
3166 if (!map
->stripes
[i
].dev
) {
3167 map
->stripes
[i
].dev
=
3168 add_missing_dev(root
, devid
, uuid
);
3169 if (!map
->stripes
[i
].dev
) {
3171 free_extent_map(em
);
3175 map
->stripes
[i
].dev
->in_fs_metadata
= 1;
3178 write_lock(&map_tree
->map_tree
.lock
);
3179 ret
= add_extent_mapping(&map_tree
->map_tree
, em
);
3180 write_unlock(&map_tree
->map_tree
.lock
);
3182 free_extent_map(em
);
3187 static int fill_device_from_item(struct extent_buffer
*leaf
,
3188 struct btrfs_dev_item
*dev_item
,
3189 struct btrfs_device
*device
)
3193 device
->devid
= btrfs_device_id(leaf
, dev_item
);
3194 device
->disk_total_bytes
= btrfs_device_total_bytes(leaf
, dev_item
);
3195 device
->total_bytes
= device
->disk_total_bytes
;
3196 device
->bytes_used
= btrfs_device_bytes_used(leaf
, dev_item
);
3197 device
->type
= btrfs_device_type(leaf
, dev_item
);
3198 device
->io_align
= btrfs_device_io_align(leaf
, dev_item
);
3199 device
->io_width
= btrfs_device_io_width(leaf
, dev_item
);
3200 device
->sector_size
= btrfs_device_sector_size(leaf
, dev_item
);
3202 ptr
= (unsigned long)btrfs_device_uuid(dev_item
);
3203 read_extent_buffer(leaf
, device
->uuid
, ptr
, BTRFS_UUID_SIZE
);
3208 static int open_seed_devices(struct btrfs_root
*root
, u8
*fsid
)
3210 struct btrfs_fs_devices
*fs_devices
;
3213 mutex_lock(&uuid_mutex
);
3215 fs_devices
= root
->fs_info
->fs_devices
->seed
;
3216 while (fs_devices
) {
3217 if (!memcmp(fs_devices
->fsid
, fsid
, BTRFS_UUID_SIZE
)) {
3221 fs_devices
= fs_devices
->seed
;
3224 fs_devices
= find_fsid(fsid
);
3230 fs_devices
= clone_fs_devices(fs_devices
);
3231 if (IS_ERR(fs_devices
)) {
3232 ret
= PTR_ERR(fs_devices
);
3236 ret
= __btrfs_open_devices(fs_devices
, FMODE_READ
,
3237 root
->fs_info
->bdev_holder
);
3241 if (!fs_devices
->seeding
) {
3242 __btrfs_close_devices(fs_devices
);
3243 free_fs_devices(fs_devices
);
3248 fs_devices
->seed
= root
->fs_info
->fs_devices
->seed
;
3249 root
->fs_info
->fs_devices
->seed
= fs_devices
;
3251 mutex_unlock(&uuid_mutex
);
3255 static int read_one_dev(struct btrfs_root
*root
,
3256 struct extent_buffer
*leaf
,
3257 struct btrfs_dev_item
*dev_item
)
3259 struct btrfs_device
*device
;
3262 u8 fs_uuid
[BTRFS_UUID_SIZE
];
3263 u8 dev_uuid
[BTRFS_UUID_SIZE
];
3265 devid
= btrfs_device_id(leaf
, dev_item
);
3266 read_extent_buffer(leaf
, dev_uuid
,
3267 (unsigned long)btrfs_device_uuid(dev_item
),
3269 read_extent_buffer(leaf
, fs_uuid
,
3270 (unsigned long)btrfs_device_fsid(dev_item
),
3273 if (memcmp(fs_uuid
, root
->fs_info
->fsid
, BTRFS_UUID_SIZE
)) {
3274 ret
= open_seed_devices(root
, fs_uuid
);
3275 if (ret
&& !btrfs_test_opt(root
, DEGRADED
))
3279 device
= btrfs_find_device(root
, devid
, dev_uuid
, fs_uuid
);
3280 if (!device
|| !device
->bdev
) {
3281 if (!btrfs_test_opt(root
, DEGRADED
))
3285 printk(KERN_WARNING
"warning devid %llu missing\n",
3286 (unsigned long long)devid
);
3287 device
= add_missing_dev(root
, devid
, dev_uuid
);
3290 } else if (!device
->missing
) {
3292 * this happens when a device that was properly setup
3293 * in the device info lists suddenly goes bad.
3294 * device->bdev is NULL, and so we have to set
3295 * device->missing to one here
3297 root
->fs_info
->fs_devices
->missing_devices
++;
3298 device
->missing
= 1;
3302 if (device
->fs_devices
!= root
->fs_info
->fs_devices
) {
3303 BUG_ON(device
->writeable
);
3304 if (device
->generation
!=
3305 btrfs_device_generation(leaf
, dev_item
))
3309 fill_device_from_item(leaf
, dev_item
, device
);
3310 device
->dev_root
= root
->fs_info
->dev_root
;
3311 device
->in_fs_metadata
= 1;
3312 if (device
->writeable
)
3313 device
->fs_devices
->total_rw_bytes
+= device
->total_bytes
;
3318 int btrfs_read_super_device(struct btrfs_root
*root
, struct extent_buffer
*buf
)
3320 struct btrfs_dev_item
*dev_item
;
3322 dev_item
= (struct btrfs_dev_item
*)offsetof(struct btrfs_super_block
,
3324 return read_one_dev(root
, buf
, dev_item
);
3327 int btrfs_read_sys_array(struct btrfs_root
*root
)
3329 struct btrfs_super_block
*super_copy
= &root
->fs_info
->super_copy
;
3330 struct extent_buffer
*sb
;
3331 struct btrfs_disk_key
*disk_key
;
3332 struct btrfs_chunk
*chunk
;
3334 unsigned long sb_ptr
;
3340 struct btrfs_key key
;
3342 sb
= btrfs_find_create_tree_block(root
, BTRFS_SUPER_INFO_OFFSET
,
3343 BTRFS_SUPER_INFO_SIZE
);
3346 btrfs_set_buffer_uptodate(sb
);
3347 btrfs_set_buffer_lockdep_class(sb
, 0);
3349 write_extent_buffer(sb
, super_copy
, 0, BTRFS_SUPER_INFO_SIZE
);
3350 array_size
= btrfs_super_sys_array_size(super_copy
);
3352 ptr
= super_copy
->sys_chunk_array
;
3353 sb_ptr
= offsetof(struct btrfs_super_block
, sys_chunk_array
);
3356 while (cur
< array_size
) {
3357 disk_key
= (struct btrfs_disk_key
*)ptr
;
3358 btrfs_disk_key_to_cpu(&key
, disk_key
);
3360 len
= sizeof(*disk_key
); ptr
+= len
;
3364 if (key
.type
== BTRFS_CHUNK_ITEM_KEY
) {
3365 chunk
= (struct btrfs_chunk
*)sb_ptr
;
3366 ret
= read_one_chunk(root
, &key
, sb
, chunk
);
3369 num_stripes
= btrfs_chunk_num_stripes(sb
, chunk
);
3370 len
= btrfs_chunk_item_size(num_stripes
);
3379 free_extent_buffer(sb
);
3383 int btrfs_read_chunk_tree(struct btrfs_root
*root
)
3385 struct btrfs_path
*path
;
3386 struct extent_buffer
*leaf
;
3387 struct btrfs_key key
;
3388 struct btrfs_key found_key
;
3392 root
= root
->fs_info
->chunk_root
;
3394 path
= btrfs_alloc_path();
3398 /* first we search for all of the device items, and then we
3399 * read in all of the chunk items. This way we can create chunk
3400 * mappings that reference all of the devices that are afound
3402 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
3406 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
3410 leaf
= path
->nodes
[0];
3411 slot
= path
->slots
[0];
3412 if (slot
>= btrfs_header_nritems(leaf
)) {
3413 ret
= btrfs_next_leaf(root
, path
);
3420 btrfs_item_key_to_cpu(leaf
, &found_key
, slot
);
3421 if (key
.objectid
== BTRFS_DEV_ITEMS_OBJECTID
) {
3422 if (found_key
.objectid
!= BTRFS_DEV_ITEMS_OBJECTID
)
3424 if (found_key
.type
== BTRFS_DEV_ITEM_KEY
) {
3425 struct btrfs_dev_item
*dev_item
;
3426 dev_item
= btrfs_item_ptr(leaf
, slot
,
3427 struct btrfs_dev_item
);
3428 ret
= read_one_dev(root
, leaf
, dev_item
);
3432 } else if (found_key
.type
== BTRFS_CHUNK_ITEM_KEY
) {
3433 struct btrfs_chunk
*chunk
;
3434 chunk
= btrfs_item_ptr(leaf
, slot
, struct btrfs_chunk
);
3435 ret
= read_one_chunk(root
, &found_key
, leaf
, chunk
);
3441 if (key
.objectid
== BTRFS_DEV_ITEMS_OBJECTID
) {
3443 btrfs_release_path(root
, path
);
3448 btrfs_free_path(path
);