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/buffer_head.h>
21 #include <linux/blkdev.h>
22 #include <linux/random.h>
23 #include <asm/div64.h>
25 #include "extent_map.h"
27 #include "transaction.h"
28 #include "print-tree.h"
30 #include "async-thread.h"
40 struct btrfs_bio_stripe stripes
[];
43 #define map_lookup_size(n) (sizeof(struct map_lookup) + \
44 (sizeof(struct btrfs_bio_stripe) * (n)))
46 static DEFINE_MUTEX(uuid_mutex
);
47 static LIST_HEAD(fs_uuids
);
49 void btrfs_lock_volumes(void)
51 mutex_lock(&uuid_mutex
);
54 void btrfs_unlock_volumes(void)
56 mutex_unlock(&uuid_mutex
);
59 int btrfs_cleanup_fs_uuids(void)
61 struct btrfs_fs_devices
*fs_devices
;
62 struct list_head
*uuid_cur
;
63 struct list_head
*devices_cur
;
64 struct btrfs_device
*dev
;
66 list_for_each(uuid_cur
, &fs_uuids
) {
67 fs_devices
= list_entry(uuid_cur
, struct btrfs_fs_devices
,
69 while(!list_empty(&fs_devices
->devices
)) {
70 devices_cur
= fs_devices
->devices
.next
;
71 dev
= list_entry(devices_cur
, struct btrfs_device
,
74 close_bdev_excl(dev
->bdev
);
75 fs_devices
->open_devices
--;
77 list_del(&dev
->dev_list
);
85 static struct btrfs_device
*__find_device(struct list_head
*head
, u64 devid
,
88 struct btrfs_device
*dev
;
89 struct list_head
*cur
;
91 list_for_each(cur
, head
) {
92 dev
= list_entry(cur
, struct btrfs_device
, dev_list
);
93 if (dev
->devid
== devid
&&
94 (!uuid
|| !memcmp(dev
->uuid
, uuid
, BTRFS_UUID_SIZE
))) {
101 static struct btrfs_fs_devices
*find_fsid(u8
*fsid
)
103 struct list_head
*cur
;
104 struct btrfs_fs_devices
*fs_devices
;
106 list_for_each(cur
, &fs_uuids
) {
107 fs_devices
= list_entry(cur
, struct btrfs_fs_devices
, list
);
108 if (memcmp(fsid
, fs_devices
->fsid
, BTRFS_FSID_SIZE
) == 0)
115 * we try to collect pending bios for a device so we don't get a large
116 * number of procs sending bios down to the same device. This greatly
117 * improves the schedulers ability to collect and merge the bios.
119 * But, it also turns into a long list of bios to process and that is sure
120 * to eventually make the worker thread block. The solution here is to
121 * make some progress and then put this work struct back at the end of
122 * the list if the block device is congested. This way, multiple devices
123 * can make progress from a single worker thread.
125 int run_scheduled_bios(struct btrfs_device
*device
)
128 struct backing_dev_info
*bdi
;
132 unsigned long num_run
= 0;
134 bdi
= device
->bdev
->bd_inode
->i_mapping
->backing_dev_info
;
136 spin_lock(&device
->io_lock
);
138 /* take all the bios off the list at once and process them
139 * later on (without the lock held). But, remember the
140 * tail and other pointers so the bios can be properly reinserted
141 * into the list if we hit congestion
143 pending
= device
->pending_bios
;
144 tail
= device
->pending_bio_tail
;
145 WARN_ON(pending
&& !tail
);
146 device
->pending_bios
= NULL
;
147 device
->pending_bio_tail
= NULL
;
150 * if pending was null this time around, no bios need processing
151 * at all and we can stop. Otherwise it'll loop back up again
152 * and do an additional check so no bios are missed.
154 * device->running_pending is used to synchronize with the
159 device
->running_pending
= 1;
162 device
->running_pending
= 0;
164 spin_unlock(&device
->io_lock
);
168 pending
= pending
->bi_next
;
170 atomic_dec(&device
->dev_root
->fs_info
->nr_async_submits
);
171 submit_bio(cur
->bi_rw
, cur
);
175 * we made progress, there is more work to do and the bdi
176 * is now congested. Back off and let other work structs
179 if (pending
&& num_run
&& bdi_write_congested(bdi
)) {
180 struct bio
*old_head
;
182 spin_lock(&device
->io_lock
);
183 old_head
= device
->pending_bios
;
184 device
->pending_bios
= pending
;
185 if (device
->pending_bio_tail
)
186 tail
->bi_next
= old_head
;
188 device
->pending_bio_tail
= tail
;
190 spin_unlock(&device
->io_lock
);
191 btrfs_requeue_work(&device
->work
);
201 void pending_bios_fn(struct btrfs_work
*work
)
203 struct btrfs_device
*device
;
205 device
= container_of(work
, struct btrfs_device
, work
);
206 run_scheduled_bios(device
);
209 static int device_list_add(const char *path
,
210 struct btrfs_super_block
*disk_super
,
211 u64 devid
, struct btrfs_fs_devices
**fs_devices_ret
)
213 struct btrfs_device
*device
;
214 struct btrfs_fs_devices
*fs_devices
;
215 u64 found_transid
= btrfs_super_generation(disk_super
);
217 fs_devices
= find_fsid(disk_super
->fsid
);
219 fs_devices
= kzalloc(sizeof(*fs_devices
), GFP_NOFS
);
222 INIT_LIST_HEAD(&fs_devices
->devices
);
223 INIT_LIST_HEAD(&fs_devices
->alloc_list
);
224 list_add(&fs_devices
->list
, &fs_uuids
);
225 memcpy(fs_devices
->fsid
, disk_super
->fsid
, BTRFS_FSID_SIZE
);
226 fs_devices
->latest_devid
= devid
;
227 fs_devices
->latest_trans
= found_transid
;
230 device
= __find_device(&fs_devices
->devices
, devid
,
231 disk_super
->dev_item
.uuid
);
234 device
= kzalloc(sizeof(*device
), GFP_NOFS
);
236 /* we can safely leave the fs_devices entry around */
239 device
->devid
= devid
;
240 device
->work
.func
= pending_bios_fn
;
241 memcpy(device
->uuid
, disk_super
->dev_item
.uuid
,
243 device
->barriers
= 1;
244 spin_lock_init(&device
->io_lock
);
245 device
->name
= kstrdup(path
, GFP_NOFS
);
250 list_add(&device
->dev_list
, &fs_devices
->devices
);
251 list_add(&device
->dev_alloc_list
, &fs_devices
->alloc_list
);
252 fs_devices
->num_devices
++;
255 if (found_transid
> fs_devices
->latest_trans
) {
256 fs_devices
->latest_devid
= devid
;
257 fs_devices
->latest_trans
= found_transid
;
259 *fs_devices_ret
= fs_devices
;
263 int btrfs_close_extra_devices(struct btrfs_fs_devices
*fs_devices
)
265 struct list_head
*head
= &fs_devices
->devices
;
266 struct list_head
*cur
;
267 struct btrfs_device
*device
;
269 mutex_lock(&uuid_mutex
);
271 list_for_each(cur
, head
) {
272 device
= list_entry(cur
, struct btrfs_device
, dev_list
);
273 if (!device
->in_fs_metadata
) {
274 struct block_device
*bdev
;
275 list_del(&device
->dev_list
);
276 list_del(&device
->dev_alloc_list
);
277 fs_devices
->num_devices
--;
280 fs_devices
->open_devices
--;
281 mutex_unlock(&uuid_mutex
);
282 close_bdev_excl(bdev
);
283 mutex_lock(&uuid_mutex
);
290 mutex_unlock(&uuid_mutex
);
294 int btrfs_close_devices(struct btrfs_fs_devices
*fs_devices
)
296 struct list_head
*head
= &fs_devices
->devices
;
297 struct list_head
*cur
;
298 struct btrfs_device
*device
;
300 mutex_lock(&uuid_mutex
);
301 list_for_each(cur
, head
) {
302 device
= list_entry(cur
, struct btrfs_device
, dev_list
);
304 close_bdev_excl(device
->bdev
);
305 fs_devices
->open_devices
--;
308 device
->in_fs_metadata
= 0;
310 fs_devices
->mounted
= 0;
311 mutex_unlock(&uuid_mutex
);
315 int btrfs_open_devices(struct btrfs_fs_devices
*fs_devices
,
316 int flags
, void *holder
)
318 struct block_device
*bdev
;
319 struct list_head
*head
= &fs_devices
->devices
;
320 struct list_head
*cur
;
321 struct btrfs_device
*device
;
322 struct block_device
*latest_bdev
= NULL
;
323 struct buffer_head
*bh
;
324 struct btrfs_super_block
*disk_super
;
325 u64 latest_devid
= 0;
326 u64 latest_transid
= 0;
331 mutex_lock(&uuid_mutex
);
332 if (fs_devices
->mounted
)
335 list_for_each(cur
, head
) {
336 device
= list_entry(cur
, struct btrfs_device
, dev_list
);
343 bdev
= open_bdev_excl(device
->name
, flags
, holder
);
346 printk("open %s failed\n", device
->name
);
349 set_blocksize(bdev
, 4096);
351 bh
= __bread(bdev
, BTRFS_SUPER_INFO_OFFSET
/ 4096, 4096);
355 disk_super
= (struct btrfs_super_block
*)bh
->b_data
;
356 if (strncmp((char *)(&disk_super
->magic
), BTRFS_MAGIC
,
357 sizeof(disk_super
->magic
)))
360 devid
= le64_to_cpu(disk_super
->dev_item
.devid
);
361 if (devid
!= device
->devid
)
364 transid
= btrfs_super_generation(disk_super
);
365 if (!latest_transid
|| transid
> latest_transid
) {
366 latest_devid
= devid
;
367 latest_transid
= transid
;
372 device
->in_fs_metadata
= 0;
373 fs_devices
->open_devices
++;
379 close_bdev_excl(bdev
);
383 if (fs_devices
->open_devices
== 0) {
387 fs_devices
->mounted
= 1;
388 fs_devices
->latest_bdev
= latest_bdev
;
389 fs_devices
->latest_devid
= latest_devid
;
390 fs_devices
->latest_trans
= latest_transid
;
392 mutex_unlock(&uuid_mutex
);
396 int btrfs_scan_one_device(const char *path
, int flags
, void *holder
,
397 struct btrfs_fs_devices
**fs_devices_ret
)
399 struct btrfs_super_block
*disk_super
;
400 struct block_device
*bdev
;
401 struct buffer_head
*bh
;
406 mutex_lock(&uuid_mutex
);
408 bdev
= open_bdev_excl(path
, flags
, holder
);
415 ret
= set_blocksize(bdev
, 4096);
418 bh
= __bread(bdev
, BTRFS_SUPER_INFO_OFFSET
/ 4096, 4096);
423 disk_super
= (struct btrfs_super_block
*)bh
->b_data
;
424 if (strncmp((char *)(&disk_super
->magic
), BTRFS_MAGIC
,
425 sizeof(disk_super
->magic
))) {
429 devid
= le64_to_cpu(disk_super
->dev_item
.devid
);
430 transid
= btrfs_super_generation(disk_super
);
431 if (disk_super
->label
[0])
432 printk("device label %s ", disk_super
->label
);
434 /* FIXME, make a readl uuid parser */
435 printk("device fsid %llx-%llx ",
436 *(unsigned long long *)disk_super
->fsid
,
437 *(unsigned long long *)(disk_super
->fsid
+ 8));
439 printk("devid %Lu transid %Lu %s\n", devid
, transid
, path
);
440 ret
= device_list_add(path
, disk_super
, devid
, fs_devices_ret
);
445 close_bdev_excl(bdev
);
447 mutex_unlock(&uuid_mutex
);
452 * this uses a pretty simple search, the expectation is that it is
453 * called very infrequently and that a given device has a small number
456 static int find_free_dev_extent(struct btrfs_trans_handle
*trans
,
457 struct btrfs_device
*device
,
458 struct btrfs_path
*path
,
459 u64 num_bytes
, u64
*start
)
461 struct btrfs_key key
;
462 struct btrfs_root
*root
= device
->dev_root
;
463 struct btrfs_dev_extent
*dev_extent
= NULL
;
466 u64 search_start
= 0;
467 u64 search_end
= device
->total_bytes
;
471 struct extent_buffer
*l
;
476 /* FIXME use last free of some kind */
478 /* we don't want to overwrite the superblock on the drive,
479 * so we make sure to start at an offset of at least 1MB
481 search_start
= max((u64
)1024 * 1024, search_start
);
483 if (root
->fs_info
->alloc_start
+ num_bytes
<= device
->total_bytes
)
484 search_start
= max(root
->fs_info
->alloc_start
, search_start
);
486 key
.objectid
= device
->devid
;
487 key
.offset
= search_start
;
488 key
.type
= BTRFS_DEV_EXTENT_KEY
;
489 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 0);
492 ret
= btrfs_previous_item(root
, path
, 0, key
.type
);
496 btrfs_item_key_to_cpu(l
, &key
, path
->slots
[0]);
499 slot
= path
->slots
[0];
500 if (slot
>= btrfs_header_nritems(l
)) {
501 ret
= btrfs_next_leaf(root
, path
);
508 if (search_start
>= search_end
) {
512 *start
= search_start
;
516 *start
= last_byte
> search_start
?
517 last_byte
: search_start
;
518 if (search_end
<= *start
) {
524 btrfs_item_key_to_cpu(l
, &key
, slot
);
526 if (key
.objectid
< device
->devid
)
529 if (key
.objectid
> device
->devid
)
532 if (key
.offset
>= search_start
&& key
.offset
> last_byte
&&
534 if (last_byte
< search_start
)
535 last_byte
= search_start
;
536 hole_size
= key
.offset
- last_byte
;
537 if (key
.offset
> last_byte
&&
538 hole_size
>= num_bytes
) {
543 if (btrfs_key_type(&key
) != BTRFS_DEV_EXTENT_KEY
) {
548 dev_extent
= btrfs_item_ptr(l
, slot
, struct btrfs_dev_extent
);
549 last_byte
= key
.offset
+ btrfs_dev_extent_length(l
, dev_extent
);
555 /* we have to make sure we didn't find an extent that has already
556 * been allocated by the map tree or the original allocation
558 btrfs_release_path(root
, path
);
559 BUG_ON(*start
< search_start
);
561 if (*start
+ num_bytes
> search_end
) {
565 /* check for pending inserts here */
569 btrfs_release_path(root
, path
);
573 int btrfs_free_dev_extent(struct btrfs_trans_handle
*trans
,
574 struct btrfs_device
*device
,
578 struct btrfs_path
*path
;
579 struct btrfs_root
*root
= device
->dev_root
;
580 struct btrfs_key key
;
581 struct btrfs_key found_key
;
582 struct extent_buffer
*leaf
= NULL
;
583 struct btrfs_dev_extent
*extent
= NULL
;
585 path
= btrfs_alloc_path();
589 key
.objectid
= device
->devid
;
591 key
.type
= BTRFS_DEV_EXTENT_KEY
;
593 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
595 ret
= btrfs_previous_item(root
, path
, key
.objectid
,
596 BTRFS_DEV_EXTENT_KEY
);
598 leaf
= path
->nodes
[0];
599 btrfs_item_key_to_cpu(leaf
, &found_key
, path
->slots
[0]);
600 extent
= btrfs_item_ptr(leaf
, path
->slots
[0],
601 struct btrfs_dev_extent
);
602 BUG_ON(found_key
.offset
> start
|| found_key
.offset
+
603 btrfs_dev_extent_length(leaf
, extent
) < start
);
605 } else if (ret
== 0) {
606 leaf
= path
->nodes
[0];
607 extent
= btrfs_item_ptr(leaf
, path
->slots
[0],
608 struct btrfs_dev_extent
);
612 if (device
->bytes_used
> 0)
613 device
->bytes_used
-= btrfs_dev_extent_length(leaf
, extent
);
614 ret
= btrfs_del_item(trans
, root
, path
);
617 btrfs_free_path(path
);
621 int btrfs_alloc_dev_extent(struct btrfs_trans_handle
*trans
,
622 struct btrfs_device
*device
,
623 u64 chunk_tree
, u64 chunk_objectid
,
625 u64 num_bytes
, u64
*start
)
628 struct btrfs_path
*path
;
629 struct btrfs_root
*root
= device
->dev_root
;
630 struct btrfs_dev_extent
*extent
;
631 struct extent_buffer
*leaf
;
632 struct btrfs_key key
;
634 WARN_ON(!device
->in_fs_metadata
);
635 path
= btrfs_alloc_path();
639 ret
= find_free_dev_extent(trans
, device
, path
, num_bytes
, start
);
644 key
.objectid
= device
->devid
;
646 key
.type
= BTRFS_DEV_EXTENT_KEY
;
647 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
,
651 leaf
= path
->nodes
[0];
652 extent
= btrfs_item_ptr(leaf
, path
->slots
[0],
653 struct btrfs_dev_extent
);
654 btrfs_set_dev_extent_chunk_tree(leaf
, extent
, chunk_tree
);
655 btrfs_set_dev_extent_chunk_objectid(leaf
, extent
, chunk_objectid
);
656 btrfs_set_dev_extent_chunk_offset(leaf
, extent
, chunk_offset
);
658 write_extent_buffer(leaf
, root
->fs_info
->chunk_tree_uuid
,
659 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent
),
662 btrfs_set_dev_extent_length(leaf
, extent
, num_bytes
);
663 btrfs_mark_buffer_dirty(leaf
);
665 btrfs_free_path(path
);
669 static int find_next_chunk(struct btrfs_root
*root
, u64 objectid
, u64
*offset
)
671 struct btrfs_path
*path
;
673 struct btrfs_key key
;
674 struct btrfs_chunk
*chunk
;
675 struct btrfs_key found_key
;
677 path
= btrfs_alloc_path();
680 key
.objectid
= objectid
;
681 key
.offset
= (u64
)-1;
682 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
684 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
690 ret
= btrfs_previous_item(root
, path
, 0, BTRFS_CHUNK_ITEM_KEY
);
694 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
696 if (found_key
.objectid
!= objectid
)
699 chunk
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
701 *offset
= found_key
.offset
+
702 btrfs_chunk_length(path
->nodes
[0], chunk
);
707 btrfs_free_path(path
);
711 static int find_next_devid(struct btrfs_root
*root
, struct btrfs_path
*path
,
715 struct btrfs_key key
;
716 struct btrfs_key found_key
;
718 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
719 key
.type
= BTRFS_DEV_ITEM_KEY
;
720 key
.offset
= (u64
)-1;
722 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
728 ret
= btrfs_previous_item(root
, path
, BTRFS_DEV_ITEMS_OBJECTID
,
733 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
735 *objectid
= found_key
.offset
+ 1;
739 btrfs_release_path(root
, path
);
744 * the device information is stored in the chunk root
745 * the btrfs_device struct should be fully filled in
747 int btrfs_add_device(struct btrfs_trans_handle
*trans
,
748 struct btrfs_root
*root
,
749 struct btrfs_device
*device
)
752 struct btrfs_path
*path
;
753 struct btrfs_dev_item
*dev_item
;
754 struct extent_buffer
*leaf
;
755 struct btrfs_key key
;
759 root
= root
->fs_info
->chunk_root
;
761 path
= btrfs_alloc_path();
765 ret
= find_next_devid(root
, path
, &free_devid
);
769 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
770 key
.type
= BTRFS_DEV_ITEM_KEY
;
771 key
.offset
= free_devid
;
773 ret
= btrfs_insert_empty_item(trans
, root
, path
, &key
,
778 leaf
= path
->nodes
[0];
779 dev_item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_dev_item
);
781 device
->devid
= free_devid
;
782 btrfs_set_device_id(leaf
, dev_item
, device
->devid
);
783 btrfs_set_device_type(leaf
, dev_item
, device
->type
);
784 btrfs_set_device_io_align(leaf
, dev_item
, device
->io_align
);
785 btrfs_set_device_io_width(leaf
, dev_item
, device
->io_width
);
786 btrfs_set_device_sector_size(leaf
, dev_item
, device
->sector_size
);
787 btrfs_set_device_total_bytes(leaf
, dev_item
, device
->total_bytes
);
788 btrfs_set_device_bytes_used(leaf
, dev_item
, device
->bytes_used
);
789 btrfs_set_device_group(leaf
, dev_item
, 0);
790 btrfs_set_device_seek_speed(leaf
, dev_item
, 0);
791 btrfs_set_device_bandwidth(leaf
, dev_item
, 0);
793 ptr
= (unsigned long)btrfs_device_uuid(dev_item
);
794 write_extent_buffer(leaf
, device
->uuid
, ptr
, BTRFS_UUID_SIZE
);
795 btrfs_mark_buffer_dirty(leaf
);
799 btrfs_free_path(path
);
803 static int btrfs_rm_dev_item(struct btrfs_root
*root
,
804 struct btrfs_device
*device
)
807 struct btrfs_path
*path
;
808 struct block_device
*bdev
= device
->bdev
;
809 struct btrfs_device
*next_dev
;
810 struct btrfs_key key
;
812 struct btrfs_fs_devices
*fs_devices
;
813 struct btrfs_trans_handle
*trans
;
815 root
= root
->fs_info
->chunk_root
;
817 path
= btrfs_alloc_path();
821 trans
= btrfs_start_transaction(root
, 1);
822 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
823 key
.type
= BTRFS_DEV_ITEM_KEY
;
824 key
.offset
= device
->devid
;
826 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
835 ret
= btrfs_del_item(trans
, root
, path
);
840 * at this point, the device is zero sized. We want to
841 * remove it from the devices list and zero out the old super
843 list_del_init(&device
->dev_list
);
844 list_del_init(&device
->dev_alloc_list
);
845 fs_devices
= root
->fs_info
->fs_devices
;
847 next_dev
= list_entry(fs_devices
->devices
.next
, struct btrfs_device
,
849 if (bdev
== root
->fs_info
->sb
->s_bdev
)
850 root
->fs_info
->sb
->s_bdev
= next_dev
->bdev
;
851 if (bdev
== fs_devices
->latest_bdev
)
852 fs_devices
->latest_bdev
= next_dev
->bdev
;
854 total_bytes
= btrfs_super_num_devices(&root
->fs_info
->super_copy
);
855 btrfs_set_super_num_devices(&root
->fs_info
->super_copy
,
858 btrfs_free_path(path
);
859 btrfs_commit_transaction(trans
, root
);
863 int btrfs_rm_device(struct btrfs_root
*root
, char *device_path
)
865 struct btrfs_device
*device
;
866 struct block_device
*bdev
;
867 struct buffer_head
*bh
= NULL
;
868 struct btrfs_super_block
*disk_super
;
873 mutex_lock(&root
->fs_info
->alloc_mutex
);
874 mutex_lock(&root
->fs_info
->chunk_mutex
);
875 mutex_lock(&uuid_mutex
);
877 all_avail
= root
->fs_info
->avail_data_alloc_bits
|
878 root
->fs_info
->avail_system_alloc_bits
|
879 root
->fs_info
->avail_metadata_alloc_bits
;
881 if ((all_avail
& BTRFS_BLOCK_GROUP_RAID10
) &&
882 btrfs_super_num_devices(&root
->fs_info
->super_copy
) <= 4) {
883 printk("btrfs: unable to go below four devices on raid10\n");
888 if ((all_avail
& BTRFS_BLOCK_GROUP_RAID1
) &&
889 btrfs_super_num_devices(&root
->fs_info
->super_copy
) <= 2) {
890 printk("btrfs: unable to go below two devices on raid1\n");
895 if (strcmp(device_path
, "missing") == 0) {
896 struct list_head
*cur
;
897 struct list_head
*devices
;
898 struct btrfs_device
*tmp
;
901 devices
= &root
->fs_info
->fs_devices
->devices
;
902 list_for_each(cur
, devices
) {
903 tmp
= list_entry(cur
, struct btrfs_device
, dev_list
);
904 if (tmp
->in_fs_metadata
&& !tmp
->bdev
) {
913 printk("btrfs: no missing devices found to remove\n");
918 bdev
= open_bdev_excl(device_path
, 0,
919 root
->fs_info
->bdev_holder
);
925 bh
= __bread(bdev
, BTRFS_SUPER_INFO_OFFSET
/ 4096, 4096);
930 disk_super
= (struct btrfs_super_block
*)bh
->b_data
;
931 if (strncmp((char *)(&disk_super
->magic
), BTRFS_MAGIC
,
932 sizeof(disk_super
->magic
))) {
936 if (memcmp(disk_super
->fsid
, root
->fs_info
->fsid
,
941 devid
= le64_to_cpu(disk_super
->dev_item
.devid
);
942 device
= btrfs_find_device(root
, devid
, NULL
);
949 root
->fs_info
->fs_devices
->num_devices
--;
950 root
->fs_info
->fs_devices
->open_devices
--;
952 ret
= btrfs_shrink_device(device
, 0);
957 ret
= btrfs_rm_dev_item(root
->fs_info
->chunk_root
, device
);
962 /* make sure this device isn't detected as part of
965 memset(&disk_super
->magic
, 0, sizeof(disk_super
->magic
));
966 set_buffer_dirty(bh
);
967 sync_dirty_buffer(bh
);
973 /* one close for the device struct or super_block */
974 close_bdev_excl(device
->bdev
);
977 /* one close for us */
978 close_bdev_excl(bdev
);
989 close_bdev_excl(bdev
);
991 mutex_unlock(&uuid_mutex
);
992 mutex_unlock(&root
->fs_info
->chunk_mutex
);
993 mutex_unlock(&root
->fs_info
->alloc_mutex
);
997 int btrfs_init_new_device(struct btrfs_root
*root
, char *device_path
)
999 struct btrfs_trans_handle
*trans
;
1000 struct btrfs_device
*device
;
1001 struct block_device
*bdev
;
1002 struct list_head
*cur
;
1003 struct list_head
*devices
;
1008 bdev
= open_bdev_excl(device_path
, 0, root
->fs_info
->bdev_holder
);
1013 mutex_lock(&root
->fs_info
->alloc_mutex
);
1014 mutex_lock(&root
->fs_info
->chunk_mutex
);
1016 trans
= btrfs_start_transaction(root
, 1);
1017 devices
= &root
->fs_info
->fs_devices
->devices
;
1018 list_for_each(cur
, devices
) {
1019 device
= list_entry(cur
, struct btrfs_device
, dev_list
);
1020 if (device
->bdev
== bdev
) {
1026 device
= kzalloc(sizeof(*device
), GFP_NOFS
);
1028 /* we can safely leave the fs_devices entry around */
1030 goto out_close_bdev
;
1033 device
->barriers
= 1;
1034 device
->work
.func
= pending_bios_fn
;
1035 generate_random_uuid(device
->uuid
);
1036 spin_lock_init(&device
->io_lock
);
1037 device
->name
= kstrdup(device_path
, GFP_NOFS
);
1038 if (!device
->name
) {
1040 goto out_close_bdev
;
1042 device
->io_width
= root
->sectorsize
;
1043 device
->io_align
= root
->sectorsize
;
1044 device
->sector_size
= root
->sectorsize
;
1045 device
->total_bytes
= i_size_read(bdev
->bd_inode
);
1046 device
->dev_root
= root
->fs_info
->dev_root
;
1047 device
->bdev
= bdev
;
1048 device
->in_fs_metadata
= 1;
1050 ret
= btrfs_add_device(trans
, root
, device
);
1052 goto out_close_bdev
;
1054 total_bytes
= btrfs_super_total_bytes(&root
->fs_info
->super_copy
);
1055 btrfs_set_super_total_bytes(&root
->fs_info
->super_copy
,
1056 total_bytes
+ device
->total_bytes
);
1058 total_bytes
= btrfs_super_num_devices(&root
->fs_info
->super_copy
);
1059 btrfs_set_super_num_devices(&root
->fs_info
->super_copy
,
1062 list_add(&device
->dev_list
, &root
->fs_info
->fs_devices
->devices
);
1063 list_add(&device
->dev_alloc_list
,
1064 &root
->fs_info
->fs_devices
->alloc_list
);
1065 root
->fs_info
->fs_devices
->num_devices
++;
1066 root
->fs_info
->fs_devices
->open_devices
++;
1068 btrfs_end_transaction(trans
, root
);
1069 mutex_unlock(&root
->fs_info
->chunk_mutex
);
1070 mutex_unlock(&root
->fs_info
->alloc_mutex
);
1075 close_bdev_excl(bdev
);
1079 int btrfs_update_device(struct btrfs_trans_handle
*trans
,
1080 struct btrfs_device
*device
)
1083 struct btrfs_path
*path
;
1084 struct btrfs_root
*root
;
1085 struct btrfs_dev_item
*dev_item
;
1086 struct extent_buffer
*leaf
;
1087 struct btrfs_key key
;
1089 root
= device
->dev_root
->fs_info
->chunk_root
;
1091 path
= btrfs_alloc_path();
1095 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
1096 key
.type
= BTRFS_DEV_ITEM_KEY
;
1097 key
.offset
= device
->devid
;
1099 ret
= btrfs_search_slot(trans
, root
, &key
, path
, 0, 1);
1108 leaf
= path
->nodes
[0];
1109 dev_item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_dev_item
);
1111 btrfs_set_device_id(leaf
, dev_item
, device
->devid
);
1112 btrfs_set_device_type(leaf
, dev_item
, device
->type
);
1113 btrfs_set_device_io_align(leaf
, dev_item
, device
->io_align
);
1114 btrfs_set_device_io_width(leaf
, dev_item
, device
->io_width
);
1115 btrfs_set_device_sector_size(leaf
, dev_item
, device
->sector_size
);
1116 btrfs_set_device_total_bytes(leaf
, dev_item
, device
->total_bytes
);
1117 btrfs_set_device_bytes_used(leaf
, dev_item
, device
->bytes_used
);
1118 btrfs_mark_buffer_dirty(leaf
);
1121 btrfs_free_path(path
);
1125 int btrfs_grow_device(struct btrfs_trans_handle
*trans
,
1126 struct btrfs_device
*device
, u64 new_size
)
1128 struct btrfs_super_block
*super_copy
=
1129 &device
->dev_root
->fs_info
->super_copy
;
1130 u64 old_total
= btrfs_super_total_bytes(super_copy
);
1131 u64 diff
= new_size
- device
->total_bytes
;
1133 btrfs_set_super_total_bytes(super_copy
, old_total
+ diff
);
1134 return btrfs_update_device(trans
, device
);
1137 static int btrfs_free_chunk(struct btrfs_trans_handle
*trans
,
1138 struct btrfs_root
*root
,
1139 u64 chunk_tree
, u64 chunk_objectid
,
1143 struct btrfs_path
*path
;
1144 struct btrfs_key key
;
1146 root
= root
->fs_info
->chunk_root
;
1147 path
= btrfs_alloc_path();
1151 key
.objectid
= chunk_objectid
;
1152 key
.offset
= chunk_offset
;
1153 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
1155 ret
= btrfs_search_slot(trans
, root
, &key
, path
, -1, 1);
1158 ret
= btrfs_del_item(trans
, root
, path
);
1161 btrfs_free_path(path
);
1165 int btrfs_del_sys_chunk(struct btrfs_root
*root
, u64 chunk_objectid
, u64
1168 struct btrfs_super_block
*super_copy
= &root
->fs_info
->super_copy
;
1169 struct btrfs_disk_key
*disk_key
;
1170 struct btrfs_chunk
*chunk
;
1177 struct btrfs_key key
;
1179 array_size
= btrfs_super_sys_array_size(super_copy
);
1181 ptr
= super_copy
->sys_chunk_array
;
1184 while (cur
< array_size
) {
1185 disk_key
= (struct btrfs_disk_key
*)ptr
;
1186 btrfs_disk_key_to_cpu(&key
, disk_key
);
1188 len
= sizeof(*disk_key
);
1190 if (key
.type
== BTRFS_CHUNK_ITEM_KEY
) {
1191 chunk
= (struct btrfs_chunk
*)(ptr
+ len
);
1192 num_stripes
= btrfs_stack_chunk_num_stripes(chunk
);
1193 len
+= btrfs_chunk_item_size(num_stripes
);
1198 if (key
.objectid
== chunk_objectid
&&
1199 key
.offset
== chunk_offset
) {
1200 memmove(ptr
, ptr
+ len
, array_size
- (cur
+ len
));
1202 btrfs_set_super_sys_array_size(super_copy
, array_size
);
1212 int btrfs_relocate_chunk(struct btrfs_root
*root
,
1213 u64 chunk_tree
, u64 chunk_objectid
,
1216 struct extent_map_tree
*em_tree
;
1217 struct btrfs_root
*extent_root
;
1218 struct btrfs_trans_handle
*trans
;
1219 struct extent_map
*em
;
1220 struct map_lookup
*map
;
1224 printk("btrfs relocating chunk %llu\n",
1225 (unsigned long long)chunk_offset
);
1226 root
= root
->fs_info
->chunk_root
;
1227 extent_root
= root
->fs_info
->extent_root
;
1228 em_tree
= &root
->fs_info
->mapping_tree
.map_tree
;
1230 /* step one, relocate all the extents inside this chunk */
1231 ret
= btrfs_shrink_extent_tree(extent_root
, chunk_offset
);
1234 trans
= btrfs_start_transaction(root
, 1);
1238 * step two, delete the device extents and the
1239 * chunk tree entries
1241 spin_lock(&em_tree
->lock
);
1242 em
= lookup_extent_mapping(em_tree
, chunk_offset
, 1);
1243 spin_unlock(&em_tree
->lock
);
1245 BUG_ON(em
->start
> chunk_offset
||
1246 em
->start
+ em
->len
< chunk_offset
);
1247 map
= (struct map_lookup
*)em
->bdev
;
1249 for (i
= 0; i
< map
->num_stripes
; i
++) {
1250 ret
= btrfs_free_dev_extent(trans
, map
->stripes
[i
].dev
,
1251 map
->stripes
[i
].physical
);
1254 if (map
->stripes
[i
].dev
) {
1255 ret
= btrfs_update_device(trans
, map
->stripes
[i
].dev
);
1259 ret
= btrfs_free_chunk(trans
, root
, chunk_tree
, chunk_objectid
,
1264 if (map
->type
& BTRFS_BLOCK_GROUP_SYSTEM
) {
1265 ret
= btrfs_del_sys_chunk(root
, chunk_objectid
, chunk_offset
);
1269 spin_lock(&em_tree
->lock
);
1270 remove_extent_mapping(em_tree
, em
);
1274 /* once for the tree */
1275 free_extent_map(em
);
1276 spin_unlock(&em_tree
->lock
);
1279 free_extent_map(em
);
1281 btrfs_end_transaction(trans
, root
);
1285 static u64
div_factor(u64 num
, int factor
)
1295 int btrfs_balance(struct btrfs_root
*dev_root
)
1298 struct list_head
*cur
;
1299 struct list_head
*devices
= &dev_root
->fs_info
->fs_devices
->devices
;
1300 struct btrfs_device
*device
;
1303 struct btrfs_path
*path
;
1304 struct btrfs_key key
;
1305 struct btrfs_chunk
*chunk
;
1306 struct btrfs_root
*chunk_root
= dev_root
->fs_info
->chunk_root
;
1307 struct btrfs_trans_handle
*trans
;
1308 struct btrfs_key found_key
;
1311 BUG(); /* FIXME, needs locking */
1313 dev_root
= dev_root
->fs_info
->dev_root
;
1315 /* step one make some room on all the devices */
1316 list_for_each(cur
, devices
) {
1317 device
= list_entry(cur
, struct btrfs_device
, dev_list
);
1318 old_size
= device
->total_bytes
;
1319 size_to_free
= div_factor(old_size
, 1);
1320 size_to_free
= min(size_to_free
, (u64
)1 * 1024 * 1024);
1321 if (device
->total_bytes
- device
->bytes_used
> size_to_free
)
1324 ret
= btrfs_shrink_device(device
, old_size
- size_to_free
);
1327 trans
= btrfs_start_transaction(dev_root
, 1);
1330 ret
= btrfs_grow_device(trans
, device
, old_size
);
1333 btrfs_end_transaction(trans
, dev_root
);
1336 /* step two, relocate all the chunks */
1337 path
= btrfs_alloc_path();
1340 key
.objectid
= BTRFS_FIRST_CHUNK_TREE_OBJECTID
;
1341 key
.offset
= (u64
)-1;
1342 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
1345 ret
= btrfs_search_slot(NULL
, chunk_root
, &key
, path
, 0, 0);
1350 * this shouldn't happen, it means the last relocate
1356 ret
= btrfs_previous_item(chunk_root
, path
, 0,
1357 BTRFS_CHUNK_ITEM_KEY
);
1361 btrfs_item_key_to_cpu(path
->nodes
[0], &found_key
,
1363 if (found_key
.objectid
!= key
.objectid
)
1365 chunk
= btrfs_item_ptr(path
->nodes
[0],
1367 struct btrfs_chunk
);
1368 key
.offset
= found_key
.offset
;
1369 /* chunk zero is special */
1370 if (key
.offset
== 0)
1373 ret
= btrfs_relocate_chunk(chunk_root
,
1374 chunk_root
->root_key
.objectid
,
1378 btrfs_release_path(chunk_root
, path
);
1382 btrfs_free_path(path
);
1387 * shrinking a device means finding all of the device extents past
1388 * the new size, and then following the back refs to the chunks.
1389 * The chunk relocation code actually frees the device extent
1391 int btrfs_shrink_device(struct btrfs_device
*device
, u64 new_size
)
1393 struct btrfs_trans_handle
*trans
;
1394 struct btrfs_root
*root
= device
->dev_root
;
1395 struct btrfs_dev_extent
*dev_extent
= NULL
;
1396 struct btrfs_path
*path
;
1403 struct extent_buffer
*l
;
1404 struct btrfs_key key
;
1405 struct btrfs_super_block
*super_copy
= &root
->fs_info
->super_copy
;
1406 u64 old_total
= btrfs_super_total_bytes(super_copy
);
1407 u64 diff
= device
->total_bytes
- new_size
;
1410 path
= btrfs_alloc_path();
1414 trans
= btrfs_start_transaction(root
, 1);
1422 device
->total_bytes
= new_size
;
1423 ret
= btrfs_update_device(trans
, device
);
1425 btrfs_end_transaction(trans
, root
);
1428 WARN_ON(diff
> old_total
);
1429 btrfs_set_super_total_bytes(super_copy
, old_total
- diff
);
1430 btrfs_end_transaction(trans
, root
);
1432 key
.objectid
= device
->devid
;
1433 key
.offset
= (u64
)-1;
1434 key
.type
= BTRFS_DEV_EXTENT_KEY
;
1437 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
1441 ret
= btrfs_previous_item(root
, path
, 0, key
.type
);
1450 slot
= path
->slots
[0];
1451 btrfs_item_key_to_cpu(l
, &key
, path
->slots
[0]);
1453 if (key
.objectid
!= device
->devid
)
1456 dev_extent
= btrfs_item_ptr(l
, slot
, struct btrfs_dev_extent
);
1457 length
= btrfs_dev_extent_length(l
, dev_extent
);
1459 if (key
.offset
+ length
<= new_size
)
1462 chunk_tree
= btrfs_dev_extent_chunk_tree(l
, dev_extent
);
1463 chunk_objectid
= btrfs_dev_extent_chunk_objectid(l
, dev_extent
);
1464 chunk_offset
= btrfs_dev_extent_chunk_offset(l
, dev_extent
);
1465 btrfs_release_path(root
, path
);
1467 ret
= btrfs_relocate_chunk(root
, chunk_tree
, chunk_objectid
,
1474 btrfs_free_path(path
);
1478 int btrfs_add_system_chunk(struct btrfs_trans_handle
*trans
,
1479 struct btrfs_root
*root
,
1480 struct btrfs_key
*key
,
1481 struct btrfs_chunk
*chunk
, int item_size
)
1483 struct btrfs_super_block
*super_copy
= &root
->fs_info
->super_copy
;
1484 struct btrfs_disk_key disk_key
;
1488 array_size
= btrfs_super_sys_array_size(super_copy
);
1489 if (array_size
+ item_size
> BTRFS_SYSTEM_CHUNK_ARRAY_SIZE
)
1492 ptr
= super_copy
->sys_chunk_array
+ array_size
;
1493 btrfs_cpu_key_to_disk(&disk_key
, key
);
1494 memcpy(ptr
, &disk_key
, sizeof(disk_key
));
1495 ptr
+= sizeof(disk_key
);
1496 memcpy(ptr
, chunk
, item_size
);
1497 item_size
+= sizeof(disk_key
);
1498 btrfs_set_super_sys_array_size(super_copy
, array_size
+ item_size
);
1502 static u64
chunk_bytes_by_type(u64 type
, u64 calc_size
, int num_stripes
,
1505 if (type
& (BTRFS_BLOCK_GROUP_RAID1
| BTRFS_BLOCK_GROUP_DUP
))
1507 else if (type
& BTRFS_BLOCK_GROUP_RAID10
)
1508 return calc_size
* (num_stripes
/ sub_stripes
);
1510 return calc_size
* num_stripes
;
1514 int btrfs_alloc_chunk(struct btrfs_trans_handle
*trans
,
1515 struct btrfs_root
*extent_root
, u64
*start
,
1516 u64
*num_bytes
, u64 type
)
1519 struct btrfs_fs_info
*info
= extent_root
->fs_info
;
1520 struct btrfs_root
*chunk_root
= extent_root
->fs_info
->chunk_root
;
1521 struct btrfs_path
*path
;
1522 struct btrfs_stripe
*stripes
;
1523 struct btrfs_device
*device
= NULL
;
1524 struct btrfs_chunk
*chunk
;
1525 struct list_head private_devs
;
1526 struct list_head
*dev_list
;
1527 struct list_head
*cur
;
1528 struct extent_map_tree
*em_tree
;
1529 struct map_lookup
*map
;
1530 struct extent_map
*em
;
1531 int min_stripe_size
= 1 * 1024 * 1024;
1533 u64 calc_size
= 1024 * 1024 * 1024;
1534 u64 max_chunk_size
= calc_size
;
1539 int num_stripes
= 1;
1540 int min_stripes
= 1;
1541 int sub_stripes
= 0;
1545 int stripe_len
= 64 * 1024;
1546 struct btrfs_key key
;
1548 if ((type
& BTRFS_BLOCK_GROUP_RAID1
) &&
1549 (type
& BTRFS_BLOCK_GROUP_DUP
)) {
1551 type
&= ~BTRFS_BLOCK_GROUP_DUP
;
1553 dev_list
= &extent_root
->fs_info
->fs_devices
->alloc_list
;
1554 if (list_empty(dev_list
))
1557 if (type
& (BTRFS_BLOCK_GROUP_RAID0
)) {
1558 num_stripes
= extent_root
->fs_info
->fs_devices
->open_devices
;
1561 if (type
& (BTRFS_BLOCK_GROUP_DUP
)) {
1565 if (type
& (BTRFS_BLOCK_GROUP_RAID1
)) {
1566 num_stripes
= min_t(u64
, 2,
1567 extent_root
->fs_info
->fs_devices
->open_devices
);
1568 if (num_stripes
< 2)
1572 if (type
& (BTRFS_BLOCK_GROUP_RAID10
)) {
1573 num_stripes
= extent_root
->fs_info
->fs_devices
->open_devices
;
1574 if (num_stripes
< 4)
1576 num_stripes
&= ~(u32
)1;
1581 if (type
& BTRFS_BLOCK_GROUP_DATA
) {
1582 max_chunk_size
= 10 * calc_size
;
1583 min_stripe_size
= 64 * 1024 * 1024;
1584 } else if (type
& BTRFS_BLOCK_GROUP_METADATA
) {
1585 max_chunk_size
= 4 * calc_size
;
1586 min_stripe_size
= 32 * 1024 * 1024;
1587 } else if (type
& BTRFS_BLOCK_GROUP_SYSTEM
) {
1588 calc_size
= 8 * 1024 * 1024;
1589 max_chunk_size
= calc_size
* 2;
1590 min_stripe_size
= 1 * 1024 * 1024;
1593 path
= btrfs_alloc_path();
1597 /* we don't want a chunk larger than 10% of the FS */
1598 percent_max
= div_factor(btrfs_super_total_bytes(&info
->super_copy
), 1);
1599 max_chunk_size
= min(percent_max
, max_chunk_size
);
1602 if (calc_size
* num_stripes
> max_chunk_size
) {
1603 calc_size
= max_chunk_size
;
1604 do_div(calc_size
, num_stripes
);
1605 do_div(calc_size
, stripe_len
);
1606 calc_size
*= stripe_len
;
1608 /* we don't want tiny stripes */
1609 calc_size
= max_t(u64
, min_stripe_size
, calc_size
);
1611 do_div(calc_size
, stripe_len
);
1612 calc_size
*= stripe_len
;
1614 INIT_LIST_HEAD(&private_devs
);
1615 cur
= dev_list
->next
;
1618 if (type
& BTRFS_BLOCK_GROUP_DUP
)
1619 min_free
= calc_size
* 2;
1621 min_free
= calc_size
;
1623 /* we add 1MB because we never use the first 1MB of the device */
1624 min_free
+= 1024 * 1024;
1626 /* build a private list of devices we will allocate from */
1627 while(index
< num_stripes
) {
1628 device
= list_entry(cur
, struct btrfs_device
, dev_alloc_list
);
1630 if (device
->total_bytes
> device
->bytes_used
)
1631 avail
= device
->total_bytes
- device
->bytes_used
;
1636 if (device
->in_fs_metadata
&& avail
>= min_free
) {
1637 u64 ignored_start
= 0;
1638 ret
= find_free_dev_extent(trans
, device
, path
,
1642 list_move_tail(&device
->dev_alloc_list
,
1645 if (type
& BTRFS_BLOCK_GROUP_DUP
)
1648 } else if (device
->in_fs_metadata
&& avail
> max_avail
)
1650 if (cur
== dev_list
)
1653 if (index
< num_stripes
) {
1654 list_splice(&private_devs
, dev_list
);
1655 if (index
>= min_stripes
) {
1656 num_stripes
= index
;
1657 if (type
& (BTRFS_BLOCK_GROUP_RAID10
)) {
1658 num_stripes
/= sub_stripes
;
1659 num_stripes
*= sub_stripes
;
1664 if (!looped
&& max_avail
> 0) {
1666 calc_size
= max_avail
;
1669 btrfs_free_path(path
);
1672 key
.objectid
= BTRFS_FIRST_CHUNK_TREE_OBJECTID
;
1673 key
.type
= BTRFS_CHUNK_ITEM_KEY
;
1674 ret
= find_next_chunk(chunk_root
, BTRFS_FIRST_CHUNK_TREE_OBJECTID
,
1677 btrfs_free_path(path
);
1681 chunk
= kmalloc(btrfs_chunk_item_size(num_stripes
), GFP_NOFS
);
1683 btrfs_free_path(path
);
1687 map
= kmalloc(map_lookup_size(num_stripes
), GFP_NOFS
);
1690 btrfs_free_path(path
);
1693 btrfs_free_path(path
);
1696 stripes
= &chunk
->stripe
;
1697 *num_bytes
= chunk_bytes_by_type(type
, calc_size
,
1698 num_stripes
, sub_stripes
);
1701 while(index
< num_stripes
) {
1702 struct btrfs_stripe
*stripe
;
1703 BUG_ON(list_empty(&private_devs
));
1704 cur
= private_devs
.next
;
1705 device
= list_entry(cur
, struct btrfs_device
, dev_alloc_list
);
1707 /* loop over this device again if we're doing a dup group */
1708 if (!(type
& BTRFS_BLOCK_GROUP_DUP
) ||
1709 (index
== num_stripes
- 1))
1710 list_move_tail(&device
->dev_alloc_list
, dev_list
);
1712 ret
= btrfs_alloc_dev_extent(trans
, device
,
1713 info
->chunk_root
->root_key
.objectid
,
1714 BTRFS_FIRST_CHUNK_TREE_OBJECTID
, key
.offset
,
1715 calc_size
, &dev_offset
);
1717 device
->bytes_used
+= calc_size
;
1718 ret
= btrfs_update_device(trans
, device
);
1721 map
->stripes
[index
].dev
= device
;
1722 map
->stripes
[index
].physical
= dev_offset
;
1723 stripe
= stripes
+ index
;
1724 btrfs_set_stack_stripe_devid(stripe
, device
->devid
);
1725 btrfs_set_stack_stripe_offset(stripe
, dev_offset
);
1726 memcpy(stripe
->dev_uuid
, device
->uuid
, BTRFS_UUID_SIZE
);
1727 physical
= dev_offset
;
1730 BUG_ON(!list_empty(&private_devs
));
1732 /* key was set above */
1733 btrfs_set_stack_chunk_length(chunk
, *num_bytes
);
1734 btrfs_set_stack_chunk_owner(chunk
, extent_root
->root_key
.objectid
);
1735 btrfs_set_stack_chunk_stripe_len(chunk
, stripe_len
);
1736 btrfs_set_stack_chunk_type(chunk
, type
);
1737 btrfs_set_stack_chunk_num_stripes(chunk
, num_stripes
);
1738 btrfs_set_stack_chunk_io_align(chunk
, stripe_len
);
1739 btrfs_set_stack_chunk_io_width(chunk
, stripe_len
);
1740 btrfs_set_stack_chunk_sector_size(chunk
, extent_root
->sectorsize
);
1741 btrfs_set_stack_chunk_sub_stripes(chunk
, sub_stripes
);
1742 map
->sector_size
= extent_root
->sectorsize
;
1743 map
->stripe_len
= stripe_len
;
1744 map
->io_align
= stripe_len
;
1745 map
->io_width
= stripe_len
;
1747 map
->num_stripes
= num_stripes
;
1748 map
->sub_stripes
= sub_stripes
;
1750 ret
= btrfs_insert_item(trans
, chunk_root
, &key
, chunk
,
1751 btrfs_chunk_item_size(num_stripes
));
1753 *start
= key
.offset
;;
1755 em
= alloc_extent_map(GFP_NOFS
);
1758 em
->bdev
= (struct block_device
*)map
;
1759 em
->start
= key
.offset
;
1760 em
->len
= *num_bytes
;
1761 em
->block_start
= 0;
1763 if (type
& BTRFS_BLOCK_GROUP_SYSTEM
) {
1764 ret
= btrfs_add_system_chunk(trans
, chunk_root
, &key
,
1765 chunk
, btrfs_chunk_item_size(num_stripes
));
1770 em_tree
= &extent_root
->fs_info
->mapping_tree
.map_tree
;
1771 spin_lock(&em_tree
->lock
);
1772 ret
= add_extent_mapping(em_tree
, em
);
1773 spin_unlock(&em_tree
->lock
);
1775 free_extent_map(em
);
1779 void btrfs_mapping_init(struct btrfs_mapping_tree
*tree
)
1781 extent_map_tree_init(&tree
->map_tree
, GFP_NOFS
);
1784 void btrfs_mapping_tree_free(struct btrfs_mapping_tree
*tree
)
1786 struct extent_map
*em
;
1789 spin_lock(&tree
->map_tree
.lock
);
1790 em
= lookup_extent_mapping(&tree
->map_tree
, 0, (u64
)-1);
1792 remove_extent_mapping(&tree
->map_tree
, em
);
1793 spin_unlock(&tree
->map_tree
.lock
);
1798 free_extent_map(em
);
1799 /* once for the tree */
1800 free_extent_map(em
);
1804 int btrfs_num_copies(struct btrfs_mapping_tree
*map_tree
, u64 logical
, u64 len
)
1806 struct extent_map
*em
;
1807 struct map_lookup
*map
;
1808 struct extent_map_tree
*em_tree
= &map_tree
->map_tree
;
1811 spin_lock(&em_tree
->lock
);
1812 em
= lookup_extent_mapping(em_tree
, logical
, len
);
1813 spin_unlock(&em_tree
->lock
);
1816 BUG_ON(em
->start
> logical
|| em
->start
+ em
->len
< logical
);
1817 map
= (struct map_lookup
*)em
->bdev
;
1818 if (map
->type
& (BTRFS_BLOCK_GROUP_DUP
| BTRFS_BLOCK_GROUP_RAID1
))
1819 ret
= map
->num_stripes
;
1820 else if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
)
1821 ret
= map
->sub_stripes
;
1824 free_extent_map(em
);
1828 static int find_live_mirror(struct map_lookup
*map
, int first
, int num
,
1832 if (map
->stripes
[optimal
].dev
->bdev
)
1834 for (i
= first
; i
< first
+ num
; i
++) {
1835 if (map
->stripes
[i
].dev
->bdev
)
1838 /* we couldn't find one that doesn't fail. Just return something
1839 * and the io error handling code will clean up eventually
1844 static int __btrfs_map_block(struct btrfs_mapping_tree
*map_tree
, int rw
,
1845 u64 logical
, u64
*length
,
1846 struct btrfs_multi_bio
**multi_ret
,
1847 int mirror_num
, struct page
*unplug_page
)
1849 struct extent_map
*em
;
1850 struct map_lookup
*map
;
1851 struct extent_map_tree
*em_tree
= &map_tree
->map_tree
;
1855 int stripes_allocated
= 8;
1856 int stripes_required
= 1;
1861 struct btrfs_multi_bio
*multi
= NULL
;
1863 if (multi_ret
&& !(rw
& (1 << BIO_RW
))) {
1864 stripes_allocated
= 1;
1868 multi
= kzalloc(btrfs_multi_bio_size(stripes_allocated
),
1873 atomic_set(&multi
->error
, 0);
1876 spin_lock(&em_tree
->lock
);
1877 em
= lookup_extent_mapping(em_tree
, logical
, *length
);
1878 spin_unlock(&em_tree
->lock
);
1880 if (!em
&& unplug_page
)
1884 printk("unable to find logical %Lu len %Lu\n", logical
, *length
);
1888 BUG_ON(em
->start
> logical
|| em
->start
+ em
->len
< logical
);
1889 map
= (struct map_lookup
*)em
->bdev
;
1890 offset
= logical
- em
->start
;
1892 if (mirror_num
> map
->num_stripes
)
1895 /* if our multi bio struct is too small, back off and try again */
1896 if (rw
& (1 << BIO_RW
)) {
1897 if (map
->type
& (BTRFS_BLOCK_GROUP_RAID1
|
1898 BTRFS_BLOCK_GROUP_DUP
)) {
1899 stripes_required
= map
->num_stripes
;
1901 } else if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
) {
1902 stripes_required
= map
->sub_stripes
;
1906 if (multi_ret
&& rw
== WRITE
&&
1907 stripes_allocated
< stripes_required
) {
1908 stripes_allocated
= map
->num_stripes
;
1909 free_extent_map(em
);
1915 * stripe_nr counts the total number of stripes we have to stride
1916 * to get to this block
1918 do_div(stripe_nr
, map
->stripe_len
);
1920 stripe_offset
= stripe_nr
* map
->stripe_len
;
1921 BUG_ON(offset
< stripe_offset
);
1923 /* stripe_offset is the offset of this block in its stripe*/
1924 stripe_offset
= offset
- stripe_offset
;
1926 if (map
->type
& (BTRFS_BLOCK_GROUP_RAID0
| BTRFS_BLOCK_GROUP_RAID1
|
1927 BTRFS_BLOCK_GROUP_RAID10
|
1928 BTRFS_BLOCK_GROUP_DUP
)) {
1929 /* we limit the length of each bio to what fits in a stripe */
1930 *length
= min_t(u64
, em
->len
- offset
,
1931 map
->stripe_len
- stripe_offset
);
1933 *length
= em
->len
- offset
;
1936 if (!multi_ret
&& !unplug_page
)
1941 if (map
->type
& BTRFS_BLOCK_GROUP_RAID1
) {
1942 if (unplug_page
|| (rw
& (1 << BIO_RW
)))
1943 num_stripes
= map
->num_stripes
;
1944 else if (mirror_num
)
1945 stripe_index
= mirror_num
- 1;
1947 stripe_index
= find_live_mirror(map
, 0,
1949 current
->pid
% map
->num_stripes
);
1952 } else if (map
->type
& BTRFS_BLOCK_GROUP_DUP
) {
1953 if (rw
& (1 << BIO_RW
))
1954 num_stripes
= map
->num_stripes
;
1955 else if (mirror_num
)
1956 stripe_index
= mirror_num
- 1;
1958 } else if (map
->type
& BTRFS_BLOCK_GROUP_RAID10
) {
1959 int factor
= map
->num_stripes
/ map
->sub_stripes
;
1961 stripe_index
= do_div(stripe_nr
, factor
);
1962 stripe_index
*= map
->sub_stripes
;
1964 if (unplug_page
|| (rw
& (1 << BIO_RW
)))
1965 num_stripes
= map
->sub_stripes
;
1966 else if (mirror_num
)
1967 stripe_index
+= mirror_num
- 1;
1969 stripe_index
= find_live_mirror(map
, stripe_index
,
1970 map
->sub_stripes
, stripe_index
+
1971 current
->pid
% map
->sub_stripes
);
1975 * after this do_div call, stripe_nr is the number of stripes
1976 * on this device we have to walk to find the data, and
1977 * stripe_index is the number of our device in the stripe array
1979 stripe_index
= do_div(stripe_nr
, map
->num_stripes
);
1981 BUG_ON(stripe_index
>= map
->num_stripes
);
1983 for (i
= 0; i
< num_stripes
; i
++) {
1985 struct btrfs_device
*device
;
1986 struct backing_dev_info
*bdi
;
1988 device
= map
->stripes
[stripe_index
].dev
;
1990 bdi
= blk_get_backing_dev_info(device
->bdev
);
1991 if (bdi
->unplug_io_fn
) {
1992 bdi
->unplug_io_fn(bdi
, unplug_page
);
1996 multi
->stripes
[i
].physical
=
1997 map
->stripes
[stripe_index
].physical
+
1998 stripe_offset
+ stripe_nr
* map
->stripe_len
;
1999 multi
->stripes
[i
].dev
= map
->stripes
[stripe_index
].dev
;
2005 multi
->num_stripes
= num_stripes
;
2006 multi
->max_errors
= max_errors
;
2009 free_extent_map(em
);
2013 int btrfs_map_block(struct btrfs_mapping_tree
*map_tree
, int rw
,
2014 u64 logical
, u64
*length
,
2015 struct btrfs_multi_bio
**multi_ret
, int mirror_num
)
2017 return __btrfs_map_block(map_tree
, rw
, logical
, length
, multi_ret
,
2021 int btrfs_unplug_page(struct btrfs_mapping_tree
*map_tree
,
2022 u64 logical
, struct page
*page
)
2024 u64 length
= PAGE_CACHE_SIZE
;
2025 return __btrfs_map_block(map_tree
, READ
, logical
, &length
,
2030 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
2031 static void end_bio_multi_stripe(struct bio
*bio
, int err
)
2033 static int end_bio_multi_stripe(struct bio
*bio
,
2034 unsigned int bytes_done
, int err
)
2037 struct btrfs_multi_bio
*multi
= bio
->bi_private
;
2039 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
2044 atomic_inc(&multi
->error
);
2046 if (atomic_dec_and_test(&multi
->stripes_pending
)) {
2047 bio
->bi_private
= multi
->private;
2048 bio
->bi_end_io
= multi
->end_io
;
2049 /* only send an error to the higher layers if it is
2050 * beyond the tolerance of the multi-bio
2052 if (atomic_read(&multi
->error
) > multi
->max_errors
) {
2056 * this bio is actually up to date, we didn't
2057 * go over the max number of errors
2059 set_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2064 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
2065 bio_endio(bio
, bio
->bi_size
, err
);
2067 bio_endio(bio
, err
);
2072 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
2077 struct async_sched
{
2080 struct btrfs_fs_info
*info
;
2081 struct btrfs_work work
;
2085 * see run_scheduled_bios for a description of why bios are collected for
2088 * This will add one bio to the pending list for a device and make sure
2089 * the work struct is scheduled.
2091 int schedule_bio(struct btrfs_root
*root
, struct btrfs_device
*device
,
2092 int rw
, struct bio
*bio
)
2094 int should_queue
= 1;
2096 /* don't bother with additional async steps for reads, right now */
2097 if (!(rw
& (1 << BIO_RW
))) {
2098 submit_bio(rw
, bio
);
2103 * nr_async_sumbits allows us to reliably return congestion to the
2104 * higher layers. Otherwise, the async bio makes it appear we have
2105 * made progress against dirty pages when we've really just put it
2106 * on a queue for later
2108 atomic_inc(&root
->fs_info
->nr_async_submits
);
2109 bio
->bi_next
= NULL
;
2112 spin_lock(&device
->io_lock
);
2114 if (device
->pending_bio_tail
)
2115 device
->pending_bio_tail
->bi_next
= bio
;
2117 device
->pending_bio_tail
= bio
;
2118 if (!device
->pending_bios
)
2119 device
->pending_bios
= bio
;
2120 if (device
->running_pending
)
2123 spin_unlock(&device
->io_lock
);
2126 btrfs_queue_worker(&root
->fs_info
->submit_workers
,
2131 int btrfs_map_bio(struct btrfs_root
*root
, int rw
, struct bio
*bio
,
2132 int mirror_num
, int async_submit
)
2134 struct btrfs_mapping_tree
*map_tree
;
2135 struct btrfs_device
*dev
;
2136 struct bio
*first_bio
= bio
;
2137 u64 logical
= bio
->bi_sector
<< 9;
2140 struct btrfs_multi_bio
*multi
= NULL
;
2145 length
= bio
->bi_size
;
2146 map_tree
= &root
->fs_info
->mapping_tree
;
2147 map_length
= length
;
2149 ret
= btrfs_map_block(map_tree
, rw
, logical
, &map_length
, &multi
,
2153 total_devs
= multi
->num_stripes
;
2154 if (map_length
< length
) {
2155 printk("mapping failed logical %Lu bio len %Lu "
2156 "len %Lu\n", logical
, length
, map_length
);
2159 multi
->end_io
= first_bio
->bi_end_io
;
2160 multi
->private = first_bio
->bi_private
;
2161 atomic_set(&multi
->stripes_pending
, multi
->num_stripes
);
2163 while(dev_nr
< total_devs
) {
2164 if (total_devs
> 1) {
2165 if (dev_nr
< total_devs
- 1) {
2166 bio
= bio_clone(first_bio
, GFP_NOFS
);
2171 bio
->bi_private
= multi
;
2172 bio
->bi_end_io
= end_bio_multi_stripe
;
2174 bio
->bi_sector
= multi
->stripes
[dev_nr
].physical
>> 9;
2175 dev
= multi
->stripes
[dev_nr
].dev
;
2176 if (dev
&& dev
->bdev
) {
2177 bio
->bi_bdev
= dev
->bdev
;
2179 schedule_bio(root
, dev
, rw
, bio
);
2181 submit_bio(rw
, bio
);
2183 bio
->bi_bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
2184 bio
->bi_sector
= logical
>> 9;
2185 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
2186 bio_endio(bio
, bio
->bi_size
, -EIO
);
2188 bio_endio(bio
, -EIO
);
2193 if (total_devs
== 1)
2198 struct btrfs_device
*btrfs_find_device(struct btrfs_root
*root
, u64 devid
,
2201 struct list_head
*head
= &root
->fs_info
->fs_devices
->devices
;
2203 return __find_device(head
, devid
, uuid
);
2206 static struct btrfs_device
*add_missing_dev(struct btrfs_root
*root
,
2207 u64 devid
, u8
*dev_uuid
)
2209 struct btrfs_device
*device
;
2210 struct btrfs_fs_devices
*fs_devices
= root
->fs_info
->fs_devices
;
2212 device
= kzalloc(sizeof(*device
), GFP_NOFS
);
2213 list_add(&device
->dev_list
,
2214 &fs_devices
->devices
);
2215 list_add(&device
->dev_alloc_list
,
2216 &fs_devices
->alloc_list
);
2217 device
->barriers
= 1;
2218 device
->dev_root
= root
->fs_info
->dev_root
;
2219 device
->devid
= devid
;
2220 device
->work
.func
= pending_bios_fn
;
2221 fs_devices
->num_devices
++;
2222 spin_lock_init(&device
->io_lock
);
2223 memcpy(device
->uuid
, dev_uuid
, BTRFS_UUID_SIZE
);
2228 static int read_one_chunk(struct btrfs_root
*root
, struct btrfs_key
*key
,
2229 struct extent_buffer
*leaf
,
2230 struct btrfs_chunk
*chunk
)
2232 struct btrfs_mapping_tree
*map_tree
= &root
->fs_info
->mapping_tree
;
2233 struct map_lookup
*map
;
2234 struct extent_map
*em
;
2238 u8 uuid
[BTRFS_UUID_SIZE
];
2243 logical
= key
->offset
;
2244 length
= btrfs_chunk_length(leaf
, chunk
);
2246 spin_lock(&map_tree
->map_tree
.lock
);
2247 em
= lookup_extent_mapping(&map_tree
->map_tree
, logical
, 1);
2248 spin_unlock(&map_tree
->map_tree
.lock
);
2250 /* already mapped? */
2251 if (em
&& em
->start
<= logical
&& em
->start
+ em
->len
> logical
) {
2252 free_extent_map(em
);
2255 free_extent_map(em
);
2258 map
= kzalloc(sizeof(*map
), GFP_NOFS
);
2262 em
= alloc_extent_map(GFP_NOFS
);
2265 num_stripes
= btrfs_chunk_num_stripes(leaf
, chunk
);
2266 map
= kmalloc(map_lookup_size(num_stripes
), GFP_NOFS
);
2268 free_extent_map(em
);
2272 em
->bdev
= (struct block_device
*)map
;
2273 em
->start
= logical
;
2275 em
->block_start
= 0;
2277 map
->num_stripes
= num_stripes
;
2278 map
->io_width
= btrfs_chunk_io_width(leaf
, chunk
);
2279 map
->io_align
= btrfs_chunk_io_align(leaf
, chunk
);
2280 map
->sector_size
= btrfs_chunk_sector_size(leaf
, chunk
);
2281 map
->stripe_len
= btrfs_chunk_stripe_len(leaf
, chunk
);
2282 map
->type
= btrfs_chunk_type(leaf
, chunk
);
2283 map
->sub_stripes
= btrfs_chunk_sub_stripes(leaf
, chunk
);
2284 for (i
= 0; i
< num_stripes
; i
++) {
2285 map
->stripes
[i
].physical
=
2286 btrfs_stripe_offset_nr(leaf
, chunk
, i
);
2287 devid
= btrfs_stripe_devid_nr(leaf
, chunk
, i
);
2288 read_extent_buffer(leaf
, uuid
, (unsigned long)
2289 btrfs_stripe_dev_uuid_nr(chunk
, i
),
2291 map
->stripes
[i
].dev
= btrfs_find_device(root
, devid
, uuid
);
2293 if (!map
->stripes
[i
].dev
&& !btrfs_test_opt(root
, DEGRADED
)) {
2295 free_extent_map(em
);
2298 if (!map
->stripes
[i
].dev
) {
2299 map
->stripes
[i
].dev
=
2300 add_missing_dev(root
, devid
, uuid
);
2301 if (!map
->stripes
[i
].dev
) {
2303 free_extent_map(em
);
2307 map
->stripes
[i
].dev
->in_fs_metadata
= 1;
2310 spin_lock(&map_tree
->map_tree
.lock
);
2311 ret
= add_extent_mapping(&map_tree
->map_tree
, em
);
2312 spin_unlock(&map_tree
->map_tree
.lock
);
2314 free_extent_map(em
);
2319 static int fill_device_from_item(struct extent_buffer
*leaf
,
2320 struct btrfs_dev_item
*dev_item
,
2321 struct btrfs_device
*device
)
2325 device
->devid
= btrfs_device_id(leaf
, dev_item
);
2326 device
->total_bytes
= btrfs_device_total_bytes(leaf
, dev_item
);
2327 device
->bytes_used
= btrfs_device_bytes_used(leaf
, dev_item
);
2328 device
->type
= btrfs_device_type(leaf
, dev_item
);
2329 device
->io_align
= btrfs_device_io_align(leaf
, dev_item
);
2330 device
->io_width
= btrfs_device_io_width(leaf
, dev_item
);
2331 device
->sector_size
= btrfs_device_sector_size(leaf
, dev_item
);
2333 ptr
= (unsigned long)btrfs_device_uuid(dev_item
);
2334 read_extent_buffer(leaf
, device
->uuid
, ptr
, BTRFS_UUID_SIZE
);
2339 static int read_one_dev(struct btrfs_root
*root
,
2340 struct extent_buffer
*leaf
,
2341 struct btrfs_dev_item
*dev_item
)
2343 struct btrfs_device
*device
;
2346 u8 dev_uuid
[BTRFS_UUID_SIZE
];
2348 devid
= btrfs_device_id(leaf
, dev_item
);
2349 read_extent_buffer(leaf
, dev_uuid
,
2350 (unsigned long)btrfs_device_uuid(dev_item
),
2352 device
= btrfs_find_device(root
, devid
, dev_uuid
);
2354 printk("warning devid %Lu missing\n", devid
);
2355 device
= add_missing_dev(root
, devid
, dev_uuid
);
2360 fill_device_from_item(leaf
, dev_item
, device
);
2361 device
->dev_root
= root
->fs_info
->dev_root
;
2362 device
->in_fs_metadata
= 1;
2365 ret
= btrfs_open_device(device
);
2373 int btrfs_read_super_device(struct btrfs_root
*root
, struct extent_buffer
*buf
)
2375 struct btrfs_dev_item
*dev_item
;
2377 dev_item
= (struct btrfs_dev_item
*)offsetof(struct btrfs_super_block
,
2379 return read_one_dev(root
, buf
, dev_item
);
2382 int btrfs_read_sys_array(struct btrfs_root
*root
)
2384 struct btrfs_super_block
*super_copy
= &root
->fs_info
->super_copy
;
2385 struct extent_buffer
*sb
;
2386 struct btrfs_disk_key
*disk_key
;
2387 struct btrfs_chunk
*chunk
;
2389 unsigned long sb_ptr
;
2395 struct btrfs_key key
;
2397 sb
= btrfs_find_create_tree_block(root
, BTRFS_SUPER_INFO_OFFSET
,
2398 BTRFS_SUPER_INFO_SIZE
);
2401 btrfs_set_buffer_uptodate(sb
);
2402 write_extent_buffer(sb
, super_copy
, 0, BTRFS_SUPER_INFO_SIZE
);
2403 array_size
= btrfs_super_sys_array_size(super_copy
);
2405 ptr
= super_copy
->sys_chunk_array
;
2406 sb_ptr
= offsetof(struct btrfs_super_block
, sys_chunk_array
);
2409 while (cur
< array_size
) {
2410 disk_key
= (struct btrfs_disk_key
*)ptr
;
2411 btrfs_disk_key_to_cpu(&key
, disk_key
);
2413 len
= sizeof(*disk_key
); ptr
+= len
;
2417 if (key
.type
== BTRFS_CHUNK_ITEM_KEY
) {
2418 chunk
= (struct btrfs_chunk
*)sb_ptr
;
2419 ret
= read_one_chunk(root
, &key
, sb
, chunk
);
2422 num_stripes
= btrfs_chunk_num_stripes(sb
, chunk
);
2423 len
= btrfs_chunk_item_size(num_stripes
);
2432 free_extent_buffer(sb
);
2436 int btrfs_read_chunk_tree(struct btrfs_root
*root
)
2438 struct btrfs_path
*path
;
2439 struct extent_buffer
*leaf
;
2440 struct btrfs_key key
;
2441 struct btrfs_key found_key
;
2445 root
= root
->fs_info
->chunk_root
;
2447 path
= btrfs_alloc_path();
2451 /* first we search for all of the device items, and then we
2452 * read in all of the chunk items. This way we can create chunk
2453 * mappings that reference all of the devices that are afound
2455 key
.objectid
= BTRFS_DEV_ITEMS_OBJECTID
;
2459 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
2461 leaf
= path
->nodes
[0];
2462 slot
= path
->slots
[0];
2463 if (slot
>= btrfs_header_nritems(leaf
)) {
2464 ret
= btrfs_next_leaf(root
, path
);
2471 btrfs_item_key_to_cpu(leaf
, &found_key
, slot
);
2472 if (key
.objectid
== BTRFS_DEV_ITEMS_OBJECTID
) {
2473 if (found_key
.objectid
!= BTRFS_DEV_ITEMS_OBJECTID
)
2475 if (found_key
.type
== BTRFS_DEV_ITEM_KEY
) {
2476 struct btrfs_dev_item
*dev_item
;
2477 dev_item
= btrfs_item_ptr(leaf
, slot
,
2478 struct btrfs_dev_item
);
2479 ret
= read_one_dev(root
, leaf
, dev_item
);
2482 } else if (found_key
.type
== BTRFS_CHUNK_ITEM_KEY
) {
2483 struct btrfs_chunk
*chunk
;
2484 chunk
= btrfs_item_ptr(leaf
, slot
, struct btrfs_chunk
);
2485 ret
= read_one_chunk(root
, &found_key
, leaf
, chunk
);
2489 if (key
.objectid
== BTRFS_DEV_ITEMS_OBJECTID
) {
2491 btrfs_release_path(root
, path
);
2495 btrfs_free_path(path
);