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 <linux/capability.h>
26 #include <linux/kthread.h>
27 #include <asm/div64.h>
30 #include "extent_map.h"
32 #include "transaction.h"
33 #include "print-tree.h"
35 #include "async-thread.h"
36 #include "check-integrity.h"
38 static int init_first_rw_device(struct btrfs_trans_handle *trans,
39 struct btrfs_root *root,
40 struct btrfs_device *device);
41 static int btrfs_relocate_sys_chunks(struct btrfs_root *root);
43 static DEFINE_MUTEX(uuid_mutex);
44 static LIST_HEAD(fs_uuids);
46 static void lock_chunks(struct btrfs_root *root)
48 mutex_lock(&root->fs_info->chunk_mutex);
51 static void unlock_chunks(struct btrfs_root *root)
53 mutex_unlock(&root->fs_info->chunk_mutex);
56 static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
58 struct btrfs_device *device;
59 WARN_ON(fs_devices->opened);
60 while (!list_empty(&fs_devices->devices)) {
61 device = list_entry(fs_devices->devices.next,
62 struct btrfs_device, dev_list);
63 list_del(&device->dev_list);
70 int btrfs_cleanup_fs_uuids(void)
72 struct btrfs_fs_devices *fs_devices;
74 while (!list_empty(&fs_uuids)) {
75 fs_devices = list_entry(fs_uuids.next,
76 struct btrfs_fs_devices, list);
77 list_del(&fs_devices->list);
78 free_fs_devices(fs_devices);
83 static noinline struct btrfs_device *__find_device(struct list_head *head,
86 struct btrfs_device *dev;
88 list_for_each_entry(dev, head, dev_list) {
89 if (dev->devid == devid &&
90 (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) {
97 static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
99 struct btrfs_fs_devices *fs_devices;
101 list_for_each_entry(fs_devices, &fs_uuids, list) {
102 if (memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE) == 0)
108 static void requeue_list(struct btrfs_pending_bios *pending_bios,
109 struct bio *head, struct bio *tail)
112 struct bio *old_head;
114 old_head = pending_bios->head;
115 pending_bios->head = head;
116 if (pending_bios->tail)
117 tail->bi_next = old_head;
119 pending_bios->tail = tail;
123 * we try to collect pending bios for a device so we don't get a large
124 * number of procs sending bios down to the same device. This greatly
125 * improves the schedulers ability to collect and merge the bios.
127 * But, it also turns into a long list of bios to process and that is sure
128 * to eventually make the worker thread block. The solution here is to
129 * make some progress and then put this work struct back at the end of
130 * the list if the block device is congested. This way, multiple devices
131 * can make progress from a single worker thread.
133 static noinline int run_scheduled_bios(struct btrfs_device *device)
136 struct backing_dev_info *bdi;
137 struct btrfs_fs_info *fs_info;
138 struct btrfs_pending_bios *pending_bios;
142 unsigned long num_run;
143 unsigned long batch_run = 0;
145 unsigned long last_waited = 0;
147 int sync_pending = 0;
148 struct blk_plug plug;
151 * this function runs all the bios we've collected for
152 * a particular device. We don't want to wander off to
153 * another device without first sending all of these down.
154 * So, setup a plug here and finish it off before we return
156 blk_start_plug(&plug);
158 bdi = blk_get_backing_dev_info(device->bdev);
159 fs_info = device->dev_root->fs_info;
160 limit = btrfs_async_submit_limit(fs_info);
161 limit = limit * 2 / 3;
164 spin_lock(&device->io_lock);
169 /* take all the bios off the list at once and process them
170 * later on (without the lock held). But, remember the
171 * tail and other pointers so the bios can be properly reinserted
172 * into the list if we hit congestion
174 if (!force_reg && device->pending_sync_bios.head) {
175 pending_bios = &device->pending_sync_bios;
178 pending_bios = &device->pending_bios;
182 pending = pending_bios->head;
183 tail = pending_bios->tail;
184 WARN_ON(pending && !tail);
187 * if pending was null this time around, no bios need processing
188 * at all and we can stop. Otherwise it'll loop back up again
189 * and do an additional check so no bios are missed.
191 * device->running_pending is used to synchronize with the
194 if (device->pending_sync_bios.head == NULL &&
195 device->pending_bios.head == NULL) {
197 device->running_pending = 0;
200 device->running_pending = 1;
203 pending_bios->head = NULL;
204 pending_bios->tail = NULL;
206 spin_unlock(&device->io_lock);
211 /* we want to work on both lists, but do more bios on the
212 * sync list than the regular list
215 pending_bios != &device->pending_sync_bios &&
216 device->pending_sync_bios.head) ||
217 (num_run > 64 && pending_bios == &device->pending_sync_bios &&
218 device->pending_bios.head)) {
219 spin_lock(&device->io_lock);
220 requeue_list(pending_bios, pending, tail);
225 pending = pending->bi_next;
227 atomic_dec(&fs_info->nr_async_bios);
229 if (atomic_read(&fs_info->nr_async_bios) < limit &&
230 waitqueue_active(&fs_info->async_submit_wait))
231 wake_up(&fs_info->async_submit_wait);
233 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
236 * if we're doing the sync list, record that our
237 * plug has some sync requests on it
239 * If we're doing the regular list and there are
240 * sync requests sitting around, unplug before
243 if (pending_bios == &device->pending_sync_bios) {
245 } else if (sync_pending) {
246 blk_finish_plug(&plug);
247 blk_start_plug(&plug);
251 btrfsic_submit_bio(cur->bi_rw, cur);
258 * we made progress, there is more work to do and the bdi
259 * is now congested. Back off and let other work structs
262 if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
263 fs_info->fs_devices->open_devices > 1) {
264 struct io_context *ioc;
266 ioc = current->io_context;
269 * the main goal here is that we don't want to
270 * block if we're going to be able to submit
271 * more requests without blocking.
273 * This code does two great things, it pokes into
274 * the elevator code from a filesystem _and_
275 * it makes assumptions about how batching works.
277 if (ioc && ioc->nr_batch_requests > 0 &&
278 time_before(jiffies, ioc->last_waited + HZ/50UL) &&
280 ioc->last_waited == last_waited)) {
282 * we want to go through our batch of
283 * requests and stop. So, we copy out
284 * the ioc->last_waited time and test
285 * against it before looping
287 last_waited = ioc->last_waited;
292 spin_lock(&device->io_lock);
293 requeue_list(pending_bios, pending, tail);
294 device->running_pending = 1;
296 spin_unlock(&device->io_lock);
297 btrfs_requeue_work(&device->work);
300 /* unplug every 64 requests just for good measure */
301 if (batch_run % 64 == 0) {
302 blk_finish_plug(&plug);
303 blk_start_plug(&plug);
312 spin_lock(&device->io_lock);
313 if (device->pending_bios.head || device->pending_sync_bios.head)
315 spin_unlock(&device->io_lock);
318 blk_finish_plug(&plug);
322 static void pending_bios_fn(struct btrfs_work *work)
324 struct btrfs_device *device;
326 device = container_of(work, struct btrfs_device, work);
327 run_scheduled_bios(device);
330 static noinline int device_list_add(const char *path,
331 struct btrfs_super_block *disk_super,
332 u64 devid, struct btrfs_fs_devices **fs_devices_ret)
334 struct btrfs_device *device;
335 struct btrfs_fs_devices *fs_devices;
336 u64 found_transid = btrfs_super_generation(disk_super);
339 fs_devices = find_fsid(disk_super->fsid);
341 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
344 INIT_LIST_HEAD(&fs_devices->devices);
345 INIT_LIST_HEAD(&fs_devices->alloc_list);
346 list_add(&fs_devices->list, &fs_uuids);
347 memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
348 fs_devices->latest_devid = devid;
349 fs_devices->latest_trans = found_transid;
350 mutex_init(&fs_devices->device_list_mutex);
353 device = __find_device(&fs_devices->devices, devid,
354 disk_super->dev_item.uuid);
357 if (fs_devices->opened)
360 device = kzalloc(sizeof(*device), GFP_NOFS);
362 /* we can safely leave the fs_devices entry around */
365 device->devid = devid;
366 device->work.func = pending_bios_fn;
367 memcpy(device->uuid, disk_super->dev_item.uuid,
369 spin_lock_init(&device->io_lock);
370 device->name = kstrdup(path, GFP_NOFS);
375 INIT_LIST_HEAD(&device->dev_alloc_list);
377 /* init readahead state */
378 spin_lock_init(&device->reada_lock);
379 device->reada_curr_zone = NULL;
380 atomic_set(&device->reada_in_flight, 0);
381 device->reada_next = 0;
382 INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT);
383 INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT);
385 mutex_lock(&fs_devices->device_list_mutex);
386 list_add_rcu(&device->dev_list, &fs_devices->devices);
387 mutex_unlock(&fs_devices->device_list_mutex);
389 device->fs_devices = fs_devices;
390 fs_devices->num_devices++;
391 } else if (!device->name || strcmp(device->name, path)) {
392 name = kstrdup(path, GFP_NOFS);
397 if (device->missing) {
398 fs_devices->missing_devices--;
403 if (found_transid > fs_devices->latest_trans) {
404 fs_devices->latest_devid = devid;
405 fs_devices->latest_trans = found_transid;
407 *fs_devices_ret = fs_devices;
411 static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
413 struct btrfs_fs_devices *fs_devices;
414 struct btrfs_device *device;
415 struct btrfs_device *orig_dev;
417 fs_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
419 return ERR_PTR(-ENOMEM);
421 INIT_LIST_HEAD(&fs_devices->devices);
422 INIT_LIST_HEAD(&fs_devices->alloc_list);
423 INIT_LIST_HEAD(&fs_devices->list);
424 mutex_init(&fs_devices->device_list_mutex);
425 fs_devices->latest_devid = orig->latest_devid;
426 fs_devices->latest_trans = orig->latest_trans;
427 memcpy(fs_devices->fsid, orig->fsid, sizeof(fs_devices->fsid));
429 /* We have held the volume lock, it is safe to get the devices. */
430 list_for_each_entry(orig_dev, &orig->devices, dev_list) {
431 device = kzalloc(sizeof(*device), GFP_NOFS);
435 device->name = kstrdup(orig_dev->name, GFP_NOFS);
441 device->devid = orig_dev->devid;
442 device->work.func = pending_bios_fn;
443 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid));
444 spin_lock_init(&device->io_lock);
445 INIT_LIST_HEAD(&device->dev_list);
446 INIT_LIST_HEAD(&device->dev_alloc_list);
448 list_add(&device->dev_list, &fs_devices->devices);
449 device->fs_devices = fs_devices;
450 fs_devices->num_devices++;
454 free_fs_devices(fs_devices);
455 return ERR_PTR(-ENOMEM);
458 int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
460 struct btrfs_device *device, *next;
462 struct block_device *latest_bdev = NULL;
463 u64 latest_devid = 0;
464 u64 latest_transid = 0;
466 mutex_lock(&uuid_mutex);
468 /* This is the initialized path, it is safe to release the devices. */
469 list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
470 if (device->in_fs_metadata) {
471 if (!latest_transid ||
472 device->generation > latest_transid) {
473 latest_devid = device->devid;
474 latest_transid = device->generation;
475 latest_bdev = device->bdev;
481 blkdev_put(device->bdev, device->mode);
483 fs_devices->open_devices--;
485 if (device->writeable) {
486 list_del_init(&device->dev_alloc_list);
487 device->writeable = 0;
488 fs_devices->rw_devices--;
490 list_del_init(&device->dev_list);
491 fs_devices->num_devices--;
496 if (fs_devices->seed) {
497 fs_devices = fs_devices->seed;
501 fs_devices->latest_bdev = latest_bdev;
502 fs_devices->latest_devid = latest_devid;
503 fs_devices->latest_trans = latest_transid;
505 mutex_unlock(&uuid_mutex);
509 static void __free_device(struct work_struct *work)
511 struct btrfs_device *device;
513 device = container_of(work, struct btrfs_device, rcu_work);
516 blkdev_put(device->bdev, device->mode);
522 static void free_device(struct rcu_head *head)
524 struct btrfs_device *device;
526 device = container_of(head, struct btrfs_device, rcu);
528 INIT_WORK(&device->rcu_work, __free_device);
529 schedule_work(&device->rcu_work);
532 static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
534 struct btrfs_device *device;
536 if (--fs_devices->opened > 0)
539 mutex_lock(&fs_devices->device_list_mutex);
540 list_for_each_entry(device, &fs_devices->devices, dev_list) {
541 struct btrfs_device *new_device;
544 fs_devices->open_devices--;
546 if (device->writeable) {
547 list_del_init(&device->dev_alloc_list);
548 fs_devices->rw_devices--;
551 if (device->can_discard)
552 fs_devices->num_can_discard--;
554 new_device = kmalloc(sizeof(*new_device), GFP_NOFS);
556 memcpy(new_device, device, sizeof(*new_device));
557 new_device->name = kstrdup(device->name, GFP_NOFS);
558 BUG_ON(device->name && !new_device->name);
559 new_device->bdev = NULL;
560 new_device->writeable = 0;
561 new_device->in_fs_metadata = 0;
562 new_device->can_discard = 0;
563 list_replace_rcu(&device->dev_list, &new_device->dev_list);
565 call_rcu(&device->rcu, free_device);
567 mutex_unlock(&fs_devices->device_list_mutex);
569 WARN_ON(fs_devices->open_devices);
570 WARN_ON(fs_devices->rw_devices);
571 fs_devices->opened = 0;
572 fs_devices->seeding = 0;
577 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
579 struct btrfs_fs_devices *seed_devices = NULL;
582 mutex_lock(&uuid_mutex);
583 ret = __btrfs_close_devices(fs_devices);
584 if (!fs_devices->opened) {
585 seed_devices = fs_devices->seed;
586 fs_devices->seed = NULL;
588 mutex_unlock(&uuid_mutex);
590 while (seed_devices) {
591 fs_devices = seed_devices;
592 seed_devices = fs_devices->seed;
593 __btrfs_close_devices(fs_devices);
594 free_fs_devices(fs_devices);
599 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
600 fmode_t flags, void *holder)
602 struct request_queue *q;
603 struct block_device *bdev;
604 struct list_head *head = &fs_devices->devices;
605 struct btrfs_device *device;
606 struct block_device *latest_bdev = NULL;
607 struct buffer_head *bh;
608 struct btrfs_super_block *disk_super;
609 u64 latest_devid = 0;
610 u64 latest_transid = 0;
617 list_for_each_entry(device, head, dev_list) {
623 bdev = blkdev_get_by_path(device->name, flags, holder);
625 printk(KERN_INFO "open %s failed\n", device->name);
628 set_blocksize(bdev, 4096);
630 bh = btrfs_read_dev_super(bdev);
634 disk_super = (struct btrfs_super_block *)bh->b_data;
635 devid = btrfs_stack_device_id(&disk_super->dev_item);
636 if (devid != device->devid)
639 if (memcmp(device->uuid, disk_super->dev_item.uuid,
643 device->generation = btrfs_super_generation(disk_super);
644 if (!latest_transid || device->generation > latest_transid) {
645 latest_devid = devid;
646 latest_transid = device->generation;
650 if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) {
651 device->writeable = 0;
653 device->writeable = !bdev_read_only(bdev);
657 q = bdev_get_queue(bdev);
658 if (blk_queue_discard(q)) {
659 device->can_discard = 1;
660 fs_devices->num_can_discard++;
664 device->in_fs_metadata = 0;
665 device->mode = flags;
667 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
668 fs_devices->rotating = 1;
670 fs_devices->open_devices++;
671 if (device->writeable) {
672 fs_devices->rw_devices++;
673 list_add(&device->dev_alloc_list,
674 &fs_devices->alloc_list);
682 blkdev_put(bdev, flags);
686 if (fs_devices->open_devices == 0) {
690 fs_devices->seeding = seeding;
691 fs_devices->opened = 1;
692 fs_devices->latest_bdev = latest_bdev;
693 fs_devices->latest_devid = latest_devid;
694 fs_devices->latest_trans = latest_transid;
695 fs_devices->total_rw_bytes = 0;
700 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
701 fmode_t flags, void *holder)
705 mutex_lock(&uuid_mutex);
706 if (fs_devices->opened) {
707 fs_devices->opened++;
710 ret = __btrfs_open_devices(fs_devices, flags, holder);
712 mutex_unlock(&uuid_mutex);
716 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder,
717 struct btrfs_fs_devices **fs_devices_ret)
719 struct btrfs_super_block *disk_super;
720 struct block_device *bdev;
721 struct buffer_head *bh;
727 bdev = blkdev_get_by_path(path, flags, holder);
734 mutex_lock(&uuid_mutex);
735 ret = set_blocksize(bdev, 4096);
738 bh = btrfs_read_dev_super(bdev);
743 disk_super = (struct btrfs_super_block *)bh->b_data;
744 devid = btrfs_stack_device_id(&disk_super->dev_item);
745 transid = btrfs_super_generation(disk_super);
746 if (disk_super->label[0])
747 printk(KERN_INFO "device label %s ", disk_super->label);
749 printk(KERN_INFO "device fsid %pU ", disk_super->fsid);
750 printk(KERN_CONT "devid %llu transid %llu %s\n",
751 (unsigned long long)devid, (unsigned long long)transid, path);
752 ret = device_list_add(path, disk_super, devid, fs_devices_ret);
756 mutex_unlock(&uuid_mutex);
757 blkdev_put(bdev, flags);
762 /* helper to account the used device space in the range */
763 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start,
764 u64 end, u64 *length)
766 struct btrfs_key key;
767 struct btrfs_root *root = device->dev_root;
768 struct btrfs_dev_extent *dev_extent;
769 struct btrfs_path *path;
773 struct extent_buffer *l;
777 if (start >= device->total_bytes)
780 path = btrfs_alloc_path();
785 key.objectid = device->devid;
787 key.type = BTRFS_DEV_EXTENT_KEY;
789 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
793 ret = btrfs_previous_item(root, path, key.objectid, key.type);
800 slot = path->slots[0];
801 if (slot >= btrfs_header_nritems(l)) {
802 ret = btrfs_next_leaf(root, path);
810 btrfs_item_key_to_cpu(l, &key, slot);
812 if (key.objectid < device->devid)
815 if (key.objectid > device->devid)
818 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
821 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
822 extent_end = key.offset + btrfs_dev_extent_length(l,
824 if (key.offset <= start && extent_end > end) {
825 *length = end - start + 1;
827 } else if (key.offset <= start && extent_end > start)
828 *length += extent_end - start;
829 else if (key.offset > start && extent_end <= end)
830 *length += extent_end - key.offset;
831 else if (key.offset > start && key.offset <= end) {
832 *length += end - key.offset + 1;
834 } else if (key.offset > end)
842 btrfs_free_path(path);
847 * find_free_dev_extent - find free space in the specified device
848 * @device: the device which we search the free space in
849 * @num_bytes: the size of the free space that we need
850 * @start: store the start of the free space.
851 * @len: the size of the free space. that we find, or the size of the max
852 * free space if we don't find suitable free space
854 * this uses a pretty simple search, the expectation is that it is
855 * called very infrequently and that a given device has a small number
858 * @start is used to store the start of the free space if we find. But if we
859 * don't find suitable free space, it will be used to store the start position
860 * of the max free space.
862 * @len is used to store the size of the free space that we find.
863 * But if we don't find suitable free space, it is used to store the size of
864 * the max free space.
866 int find_free_dev_extent(struct btrfs_device *device, u64 num_bytes,
867 u64 *start, u64 *len)
869 struct btrfs_key key;
870 struct btrfs_root *root = device->dev_root;
871 struct btrfs_dev_extent *dev_extent;
872 struct btrfs_path *path;
878 u64 search_end = device->total_bytes;
881 struct extent_buffer *l;
883 /* FIXME use last free of some kind */
885 /* we don't want to overwrite the superblock on the drive,
886 * so we make sure to start at an offset of at least 1MB
888 search_start = max(root->fs_info->alloc_start, 1024ull * 1024);
890 max_hole_start = search_start;
894 if (search_start >= search_end) {
899 path = btrfs_alloc_path();
906 key.objectid = device->devid;
907 key.offset = search_start;
908 key.type = BTRFS_DEV_EXTENT_KEY;
910 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
914 ret = btrfs_previous_item(root, path, key.objectid, key.type);
921 slot = path->slots[0];
922 if (slot >= btrfs_header_nritems(l)) {
923 ret = btrfs_next_leaf(root, path);
931 btrfs_item_key_to_cpu(l, &key, slot);
933 if (key.objectid < device->devid)
936 if (key.objectid > device->devid)
939 if (btrfs_key_type(&key) != BTRFS_DEV_EXTENT_KEY)
942 if (key.offset > search_start) {
943 hole_size = key.offset - search_start;
945 if (hole_size > max_hole_size) {
946 max_hole_start = search_start;
947 max_hole_size = hole_size;
951 * If this free space is greater than which we need,
952 * it must be the max free space that we have found
953 * until now, so max_hole_start must point to the start
954 * of this free space and the length of this free space
955 * is stored in max_hole_size. Thus, we return
956 * max_hole_start and max_hole_size and go back to the
959 if (hole_size >= num_bytes) {
965 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
966 extent_end = key.offset + btrfs_dev_extent_length(l,
968 if (extent_end > search_start)
969 search_start = extent_end;
976 * At this point, search_start should be the end of
977 * allocated dev extents, and when shrinking the device,
978 * search_end may be smaller than search_start.
980 if (search_end > search_start)
981 hole_size = search_end - search_start;
983 if (hole_size > max_hole_size) {
984 max_hole_start = search_start;
985 max_hole_size = hole_size;
989 if (hole_size < num_bytes)
995 btrfs_free_path(path);
997 *start = max_hole_start;
999 *len = max_hole_size;
1003 static int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
1004 struct btrfs_device *device,
1008 struct btrfs_path *path;
1009 struct btrfs_root *root = device->dev_root;
1010 struct btrfs_key key;
1011 struct btrfs_key found_key;
1012 struct extent_buffer *leaf = NULL;
1013 struct btrfs_dev_extent *extent = NULL;
1015 path = btrfs_alloc_path();
1019 key.objectid = device->devid;
1021 key.type = BTRFS_DEV_EXTENT_KEY;
1023 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1025 ret = btrfs_previous_item(root, path, key.objectid,
1026 BTRFS_DEV_EXTENT_KEY);
1029 leaf = path->nodes[0];
1030 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1031 extent = btrfs_item_ptr(leaf, path->slots[0],
1032 struct btrfs_dev_extent);
1033 BUG_ON(found_key.offset > start || found_key.offset +
1034 btrfs_dev_extent_length(leaf, extent) < start);
1036 btrfs_release_path(path);
1038 } else if (ret == 0) {
1039 leaf = path->nodes[0];
1040 extent = btrfs_item_ptr(leaf, path->slots[0],
1041 struct btrfs_dev_extent);
1045 if (device->bytes_used > 0) {
1046 u64 len = btrfs_dev_extent_length(leaf, extent);
1047 device->bytes_used -= len;
1048 spin_lock(&root->fs_info->free_chunk_lock);
1049 root->fs_info->free_chunk_space += len;
1050 spin_unlock(&root->fs_info->free_chunk_lock);
1052 ret = btrfs_del_item(trans, root, path);
1055 btrfs_free_path(path);
1059 int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
1060 struct btrfs_device *device,
1061 u64 chunk_tree, u64 chunk_objectid,
1062 u64 chunk_offset, u64 start, u64 num_bytes)
1065 struct btrfs_path *path;
1066 struct btrfs_root *root = device->dev_root;
1067 struct btrfs_dev_extent *extent;
1068 struct extent_buffer *leaf;
1069 struct btrfs_key key;
1071 WARN_ON(!device->in_fs_metadata);
1072 path = btrfs_alloc_path();
1076 key.objectid = device->devid;
1078 key.type = BTRFS_DEV_EXTENT_KEY;
1079 ret = btrfs_insert_empty_item(trans, root, path, &key,
1083 leaf = path->nodes[0];
1084 extent = btrfs_item_ptr(leaf, path->slots[0],
1085 struct btrfs_dev_extent);
1086 btrfs_set_dev_extent_chunk_tree(leaf, extent, chunk_tree);
1087 btrfs_set_dev_extent_chunk_objectid(leaf, extent, chunk_objectid);
1088 btrfs_set_dev_extent_chunk_offset(leaf, extent, chunk_offset);
1090 write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
1091 (unsigned long)btrfs_dev_extent_chunk_tree_uuid(extent),
1094 btrfs_set_dev_extent_length(leaf, extent, num_bytes);
1095 btrfs_mark_buffer_dirty(leaf);
1096 btrfs_free_path(path);
1100 static noinline int find_next_chunk(struct btrfs_root *root,
1101 u64 objectid, u64 *offset)
1103 struct btrfs_path *path;
1105 struct btrfs_key key;
1106 struct btrfs_chunk *chunk;
1107 struct btrfs_key found_key;
1109 path = btrfs_alloc_path();
1113 key.objectid = objectid;
1114 key.offset = (u64)-1;
1115 key.type = BTRFS_CHUNK_ITEM_KEY;
1117 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1123 ret = btrfs_previous_item(root, path, 0, BTRFS_CHUNK_ITEM_KEY);
1127 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1129 if (found_key.objectid != objectid)
1132 chunk = btrfs_item_ptr(path->nodes[0], path->slots[0],
1133 struct btrfs_chunk);
1134 *offset = found_key.offset +
1135 btrfs_chunk_length(path->nodes[0], chunk);
1140 btrfs_free_path(path);
1144 static noinline int find_next_devid(struct btrfs_root *root, u64 *objectid)
1147 struct btrfs_key key;
1148 struct btrfs_key found_key;
1149 struct btrfs_path *path;
1151 root = root->fs_info->chunk_root;
1153 path = btrfs_alloc_path();
1157 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1158 key.type = BTRFS_DEV_ITEM_KEY;
1159 key.offset = (u64)-1;
1161 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1167 ret = btrfs_previous_item(root, path, BTRFS_DEV_ITEMS_OBJECTID,
1168 BTRFS_DEV_ITEM_KEY);
1172 btrfs_item_key_to_cpu(path->nodes[0], &found_key,
1174 *objectid = found_key.offset + 1;
1178 btrfs_free_path(path);
1183 * the device information is stored in the chunk root
1184 * the btrfs_device struct should be fully filled in
1186 int btrfs_add_device(struct btrfs_trans_handle *trans,
1187 struct btrfs_root *root,
1188 struct btrfs_device *device)
1191 struct btrfs_path *path;
1192 struct btrfs_dev_item *dev_item;
1193 struct extent_buffer *leaf;
1194 struct btrfs_key key;
1197 root = root->fs_info->chunk_root;
1199 path = btrfs_alloc_path();
1203 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1204 key.type = BTRFS_DEV_ITEM_KEY;
1205 key.offset = device->devid;
1207 ret = btrfs_insert_empty_item(trans, root, path, &key,
1212 leaf = path->nodes[0];
1213 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1215 btrfs_set_device_id(leaf, dev_item, device->devid);
1216 btrfs_set_device_generation(leaf, dev_item, 0);
1217 btrfs_set_device_type(leaf, dev_item, device->type);
1218 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1219 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1220 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1221 btrfs_set_device_total_bytes(leaf, dev_item, device->total_bytes);
1222 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1223 btrfs_set_device_group(leaf, dev_item, 0);
1224 btrfs_set_device_seek_speed(leaf, dev_item, 0);
1225 btrfs_set_device_bandwidth(leaf, dev_item, 0);
1226 btrfs_set_device_start_offset(leaf, dev_item, 0);
1228 ptr = (unsigned long)btrfs_device_uuid(dev_item);
1229 write_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
1230 ptr = (unsigned long)btrfs_device_fsid(dev_item);
1231 write_extent_buffer(leaf, root->fs_info->fsid, ptr, BTRFS_UUID_SIZE);
1232 btrfs_mark_buffer_dirty(leaf);
1236 btrfs_free_path(path);
1240 static int btrfs_rm_dev_item(struct btrfs_root *root,
1241 struct btrfs_device *device)
1244 struct btrfs_path *path;
1245 struct btrfs_key key;
1246 struct btrfs_trans_handle *trans;
1248 root = root->fs_info->chunk_root;
1250 path = btrfs_alloc_path();
1254 trans = btrfs_start_transaction(root, 0);
1255 if (IS_ERR(trans)) {
1256 btrfs_free_path(path);
1257 return PTR_ERR(trans);
1259 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1260 key.type = BTRFS_DEV_ITEM_KEY;
1261 key.offset = device->devid;
1264 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1273 ret = btrfs_del_item(trans, root, path);
1277 btrfs_free_path(path);
1278 unlock_chunks(root);
1279 btrfs_commit_transaction(trans, root);
1283 int btrfs_rm_device(struct btrfs_root *root, char *device_path)
1285 struct btrfs_device *device;
1286 struct btrfs_device *next_device;
1287 struct block_device *bdev;
1288 struct buffer_head *bh = NULL;
1289 struct btrfs_super_block *disk_super;
1290 struct btrfs_fs_devices *cur_devices;
1296 bool clear_super = false;
1298 mutex_lock(&uuid_mutex);
1300 all_avail = root->fs_info->avail_data_alloc_bits |
1301 root->fs_info->avail_system_alloc_bits |
1302 root->fs_info->avail_metadata_alloc_bits;
1304 if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) &&
1305 root->fs_info->fs_devices->num_devices <= 4) {
1306 printk(KERN_ERR "btrfs: unable to go below four devices "
1312 if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) &&
1313 root->fs_info->fs_devices->num_devices <= 2) {
1314 printk(KERN_ERR "btrfs: unable to go below two "
1315 "devices on raid1\n");
1320 if (strcmp(device_path, "missing") == 0) {
1321 struct list_head *devices;
1322 struct btrfs_device *tmp;
1325 devices = &root->fs_info->fs_devices->devices;
1327 * It is safe to read the devices since the volume_mutex
1330 list_for_each_entry(tmp, devices, dev_list) {
1331 if (tmp->in_fs_metadata && !tmp->bdev) {
1340 printk(KERN_ERR "btrfs: no missing devices found to "
1345 bdev = blkdev_get_by_path(device_path, FMODE_READ | FMODE_EXCL,
1346 root->fs_info->bdev_holder);
1348 ret = PTR_ERR(bdev);
1352 set_blocksize(bdev, 4096);
1353 bh = btrfs_read_dev_super(bdev);
1358 disk_super = (struct btrfs_super_block *)bh->b_data;
1359 devid = btrfs_stack_device_id(&disk_super->dev_item);
1360 dev_uuid = disk_super->dev_item.uuid;
1361 device = btrfs_find_device(root, devid, dev_uuid,
1369 if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
1370 printk(KERN_ERR "btrfs: unable to remove the only writeable "
1376 if (device->writeable) {
1378 list_del_init(&device->dev_alloc_list);
1379 unlock_chunks(root);
1380 root->fs_info->fs_devices->rw_devices--;
1384 ret = btrfs_shrink_device(device, 0);
1388 ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
1392 spin_lock(&root->fs_info->free_chunk_lock);
1393 root->fs_info->free_chunk_space = device->total_bytes -
1395 spin_unlock(&root->fs_info->free_chunk_lock);
1397 device->in_fs_metadata = 0;
1398 btrfs_scrub_cancel_dev(root, device);
1401 * the device list mutex makes sure that we don't change
1402 * the device list while someone else is writing out all
1403 * the device supers.
1406 cur_devices = device->fs_devices;
1407 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1408 list_del_rcu(&device->dev_list);
1410 device->fs_devices->num_devices--;
1412 if (device->missing)
1413 root->fs_info->fs_devices->missing_devices--;
1415 next_device = list_entry(root->fs_info->fs_devices->devices.next,
1416 struct btrfs_device, dev_list);
1417 if (device->bdev == root->fs_info->sb->s_bdev)
1418 root->fs_info->sb->s_bdev = next_device->bdev;
1419 if (device->bdev == root->fs_info->fs_devices->latest_bdev)
1420 root->fs_info->fs_devices->latest_bdev = next_device->bdev;
1423 device->fs_devices->open_devices--;
1425 call_rcu(&device->rcu, free_device);
1426 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1428 num_devices = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
1429 btrfs_set_super_num_devices(root->fs_info->super_copy, num_devices);
1431 if (cur_devices->open_devices == 0) {
1432 struct btrfs_fs_devices *fs_devices;
1433 fs_devices = root->fs_info->fs_devices;
1434 while (fs_devices) {
1435 if (fs_devices->seed == cur_devices)
1437 fs_devices = fs_devices->seed;
1439 fs_devices->seed = cur_devices->seed;
1440 cur_devices->seed = NULL;
1442 __btrfs_close_devices(cur_devices);
1443 unlock_chunks(root);
1444 free_fs_devices(cur_devices);
1448 * at this point, the device is zero sized. We want to
1449 * remove it from the devices list and zero out the old super
1452 /* make sure this device isn't detected as part of
1455 memset(&disk_super->magic, 0, sizeof(disk_super->magic));
1456 set_buffer_dirty(bh);
1457 sync_dirty_buffer(bh);
1466 blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
1468 mutex_unlock(&uuid_mutex);
1471 if (device->writeable) {
1473 list_add(&device->dev_alloc_list,
1474 &root->fs_info->fs_devices->alloc_list);
1475 unlock_chunks(root);
1476 root->fs_info->fs_devices->rw_devices++;
1482 * does all the dirty work required for changing file system's UUID.
1484 static int btrfs_prepare_sprout(struct btrfs_root *root)
1486 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
1487 struct btrfs_fs_devices *old_devices;
1488 struct btrfs_fs_devices *seed_devices;
1489 struct btrfs_super_block *disk_super = root->fs_info->super_copy;
1490 struct btrfs_device *device;
1493 BUG_ON(!mutex_is_locked(&uuid_mutex));
1494 if (!fs_devices->seeding)
1497 seed_devices = kzalloc(sizeof(*fs_devices), GFP_NOFS);
1501 old_devices = clone_fs_devices(fs_devices);
1502 if (IS_ERR(old_devices)) {
1503 kfree(seed_devices);
1504 return PTR_ERR(old_devices);
1507 list_add(&old_devices->list, &fs_uuids);
1509 memcpy(seed_devices, fs_devices, sizeof(*seed_devices));
1510 seed_devices->opened = 1;
1511 INIT_LIST_HEAD(&seed_devices->devices);
1512 INIT_LIST_HEAD(&seed_devices->alloc_list);
1513 mutex_init(&seed_devices->device_list_mutex);
1515 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1516 list_splice_init_rcu(&fs_devices->devices, &seed_devices->devices,
1518 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1520 list_splice_init(&fs_devices->alloc_list, &seed_devices->alloc_list);
1521 list_for_each_entry(device, &seed_devices->devices, dev_list) {
1522 device->fs_devices = seed_devices;
1525 fs_devices->seeding = 0;
1526 fs_devices->num_devices = 0;
1527 fs_devices->open_devices = 0;
1528 fs_devices->seed = seed_devices;
1530 generate_random_uuid(fs_devices->fsid);
1531 memcpy(root->fs_info->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1532 memcpy(disk_super->fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1533 super_flags = btrfs_super_flags(disk_super) &
1534 ~BTRFS_SUPER_FLAG_SEEDING;
1535 btrfs_set_super_flags(disk_super, super_flags);
1541 * strore the expected generation for seed devices in device items.
1543 static int btrfs_finish_sprout(struct btrfs_trans_handle *trans,
1544 struct btrfs_root *root)
1546 struct btrfs_path *path;
1547 struct extent_buffer *leaf;
1548 struct btrfs_dev_item *dev_item;
1549 struct btrfs_device *device;
1550 struct btrfs_key key;
1551 u8 fs_uuid[BTRFS_UUID_SIZE];
1552 u8 dev_uuid[BTRFS_UUID_SIZE];
1556 path = btrfs_alloc_path();
1560 root = root->fs_info->chunk_root;
1561 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1563 key.type = BTRFS_DEV_ITEM_KEY;
1566 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1570 leaf = path->nodes[0];
1572 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
1573 ret = btrfs_next_leaf(root, path);
1578 leaf = path->nodes[0];
1579 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1580 btrfs_release_path(path);
1584 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
1585 if (key.objectid != BTRFS_DEV_ITEMS_OBJECTID ||
1586 key.type != BTRFS_DEV_ITEM_KEY)
1589 dev_item = btrfs_item_ptr(leaf, path->slots[0],
1590 struct btrfs_dev_item);
1591 devid = btrfs_device_id(leaf, dev_item);
1592 read_extent_buffer(leaf, dev_uuid,
1593 (unsigned long)btrfs_device_uuid(dev_item),
1595 read_extent_buffer(leaf, fs_uuid,
1596 (unsigned long)btrfs_device_fsid(dev_item),
1598 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
1601 if (device->fs_devices->seeding) {
1602 btrfs_set_device_generation(leaf, dev_item,
1603 device->generation);
1604 btrfs_mark_buffer_dirty(leaf);
1612 btrfs_free_path(path);
1616 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
1618 struct request_queue *q;
1619 struct btrfs_trans_handle *trans;
1620 struct btrfs_device *device;
1621 struct block_device *bdev;
1622 struct list_head *devices;
1623 struct super_block *sb = root->fs_info->sb;
1625 int seeding_dev = 0;
1628 if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding)
1631 bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
1632 root->fs_info->bdev_holder);
1634 return PTR_ERR(bdev);
1636 if (root->fs_info->fs_devices->seeding) {
1638 down_write(&sb->s_umount);
1639 mutex_lock(&uuid_mutex);
1642 filemap_write_and_wait(bdev->bd_inode->i_mapping);
1644 devices = &root->fs_info->fs_devices->devices;
1646 * we have the volume lock, so we don't need the extra
1647 * device list mutex while reading the list here.
1649 list_for_each_entry(device, devices, dev_list) {
1650 if (device->bdev == bdev) {
1656 device = kzalloc(sizeof(*device), GFP_NOFS);
1658 /* we can safely leave the fs_devices entry around */
1663 device->name = kstrdup(device_path, GFP_NOFS);
1664 if (!device->name) {
1670 ret = find_next_devid(root, &device->devid);
1672 kfree(device->name);
1677 trans = btrfs_start_transaction(root, 0);
1678 if (IS_ERR(trans)) {
1679 kfree(device->name);
1681 ret = PTR_ERR(trans);
1687 q = bdev_get_queue(bdev);
1688 if (blk_queue_discard(q))
1689 device->can_discard = 1;
1690 device->writeable = 1;
1691 device->work.func = pending_bios_fn;
1692 generate_random_uuid(device->uuid);
1693 spin_lock_init(&device->io_lock);
1694 device->generation = trans->transid;
1695 device->io_width = root->sectorsize;
1696 device->io_align = root->sectorsize;
1697 device->sector_size = root->sectorsize;
1698 device->total_bytes = i_size_read(bdev->bd_inode);
1699 device->disk_total_bytes = device->total_bytes;
1700 device->dev_root = root->fs_info->dev_root;
1701 device->bdev = bdev;
1702 device->in_fs_metadata = 1;
1703 device->mode = FMODE_EXCL;
1704 set_blocksize(device->bdev, 4096);
1707 sb->s_flags &= ~MS_RDONLY;
1708 ret = btrfs_prepare_sprout(root);
1712 device->fs_devices = root->fs_info->fs_devices;
1715 * we don't want write_supers to jump in here with our device
1718 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
1719 list_add_rcu(&device->dev_list, &root->fs_info->fs_devices->devices);
1720 list_add(&device->dev_alloc_list,
1721 &root->fs_info->fs_devices->alloc_list);
1722 root->fs_info->fs_devices->num_devices++;
1723 root->fs_info->fs_devices->open_devices++;
1724 root->fs_info->fs_devices->rw_devices++;
1725 if (device->can_discard)
1726 root->fs_info->fs_devices->num_can_discard++;
1727 root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
1729 spin_lock(&root->fs_info->free_chunk_lock);
1730 root->fs_info->free_chunk_space += device->total_bytes;
1731 spin_unlock(&root->fs_info->free_chunk_lock);
1733 if (!blk_queue_nonrot(bdev_get_queue(bdev)))
1734 root->fs_info->fs_devices->rotating = 1;
1736 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
1737 btrfs_set_super_total_bytes(root->fs_info->super_copy,
1738 total_bytes + device->total_bytes);
1740 total_bytes = btrfs_super_num_devices(root->fs_info->super_copy);
1741 btrfs_set_super_num_devices(root->fs_info->super_copy,
1743 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
1746 ret = init_first_rw_device(trans, root, device);
1748 ret = btrfs_finish_sprout(trans, root);
1751 ret = btrfs_add_device(trans, root, device);
1755 * we've got more storage, clear any full flags on the space
1758 btrfs_clear_space_info_full(root->fs_info);
1760 unlock_chunks(root);
1761 btrfs_commit_transaction(trans, root);
1764 mutex_unlock(&uuid_mutex);
1765 up_write(&sb->s_umount);
1767 ret = btrfs_relocate_sys_chunks(root);
1773 blkdev_put(bdev, FMODE_EXCL);
1775 mutex_unlock(&uuid_mutex);
1776 up_write(&sb->s_umount);
1781 static noinline int btrfs_update_device(struct btrfs_trans_handle *trans,
1782 struct btrfs_device *device)
1785 struct btrfs_path *path;
1786 struct btrfs_root *root;
1787 struct btrfs_dev_item *dev_item;
1788 struct extent_buffer *leaf;
1789 struct btrfs_key key;
1791 root = device->dev_root->fs_info->chunk_root;
1793 path = btrfs_alloc_path();
1797 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
1798 key.type = BTRFS_DEV_ITEM_KEY;
1799 key.offset = device->devid;
1801 ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
1810 leaf = path->nodes[0];
1811 dev_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_item);
1813 btrfs_set_device_id(leaf, dev_item, device->devid);
1814 btrfs_set_device_type(leaf, dev_item, device->type);
1815 btrfs_set_device_io_align(leaf, dev_item, device->io_align);
1816 btrfs_set_device_io_width(leaf, dev_item, device->io_width);
1817 btrfs_set_device_sector_size(leaf, dev_item, device->sector_size);
1818 btrfs_set_device_total_bytes(leaf, dev_item, device->disk_total_bytes);
1819 btrfs_set_device_bytes_used(leaf, dev_item, device->bytes_used);
1820 btrfs_mark_buffer_dirty(leaf);
1823 btrfs_free_path(path);
1827 static int __btrfs_grow_device(struct btrfs_trans_handle *trans,
1828 struct btrfs_device *device, u64 new_size)
1830 struct btrfs_super_block *super_copy =
1831 device->dev_root->fs_info->super_copy;
1832 u64 old_total = btrfs_super_total_bytes(super_copy);
1833 u64 diff = new_size - device->total_bytes;
1835 if (!device->writeable)
1837 if (new_size <= device->total_bytes)
1840 btrfs_set_super_total_bytes(super_copy, old_total + diff);
1841 device->fs_devices->total_rw_bytes += diff;
1843 device->total_bytes = new_size;
1844 device->disk_total_bytes = new_size;
1845 btrfs_clear_space_info_full(device->dev_root->fs_info);
1847 return btrfs_update_device(trans, device);
1850 int btrfs_grow_device(struct btrfs_trans_handle *trans,
1851 struct btrfs_device *device, u64 new_size)
1854 lock_chunks(device->dev_root);
1855 ret = __btrfs_grow_device(trans, device, new_size);
1856 unlock_chunks(device->dev_root);
1860 static int btrfs_free_chunk(struct btrfs_trans_handle *trans,
1861 struct btrfs_root *root,
1862 u64 chunk_tree, u64 chunk_objectid,
1866 struct btrfs_path *path;
1867 struct btrfs_key key;
1869 root = root->fs_info->chunk_root;
1870 path = btrfs_alloc_path();
1874 key.objectid = chunk_objectid;
1875 key.offset = chunk_offset;
1876 key.type = BTRFS_CHUNK_ITEM_KEY;
1878 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1881 ret = btrfs_del_item(trans, root, path);
1883 btrfs_free_path(path);
1887 static int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64
1890 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
1891 struct btrfs_disk_key *disk_key;
1892 struct btrfs_chunk *chunk;
1899 struct btrfs_key key;
1901 array_size = btrfs_super_sys_array_size(super_copy);
1903 ptr = super_copy->sys_chunk_array;
1906 while (cur < array_size) {
1907 disk_key = (struct btrfs_disk_key *)ptr;
1908 btrfs_disk_key_to_cpu(&key, disk_key);
1910 len = sizeof(*disk_key);
1912 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
1913 chunk = (struct btrfs_chunk *)(ptr + len);
1914 num_stripes = btrfs_stack_chunk_num_stripes(chunk);
1915 len += btrfs_chunk_item_size(num_stripes);
1920 if (key.objectid == chunk_objectid &&
1921 key.offset == chunk_offset) {
1922 memmove(ptr, ptr + len, array_size - (cur + len));
1924 btrfs_set_super_sys_array_size(super_copy, array_size);
1933 static int btrfs_relocate_chunk(struct btrfs_root *root,
1934 u64 chunk_tree, u64 chunk_objectid,
1937 struct extent_map_tree *em_tree;
1938 struct btrfs_root *extent_root;
1939 struct btrfs_trans_handle *trans;
1940 struct extent_map *em;
1941 struct map_lookup *map;
1945 root = root->fs_info->chunk_root;
1946 extent_root = root->fs_info->extent_root;
1947 em_tree = &root->fs_info->mapping_tree.map_tree;
1949 ret = btrfs_can_relocate(extent_root, chunk_offset);
1953 /* step one, relocate all the extents inside this chunk */
1954 ret = btrfs_relocate_block_group(extent_root, chunk_offset);
1958 trans = btrfs_start_transaction(root, 0);
1959 BUG_ON(IS_ERR(trans));
1964 * step two, delete the device extents and the
1965 * chunk tree entries
1967 read_lock(&em_tree->lock);
1968 em = lookup_extent_mapping(em_tree, chunk_offset, 1);
1969 read_unlock(&em_tree->lock);
1971 BUG_ON(!em || em->start > chunk_offset ||
1972 em->start + em->len < chunk_offset);
1973 map = (struct map_lookup *)em->bdev;
1975 for (i = 0; i < map->num_stripes; i++) {
1976 ret = btrfs_free_dev_extent(trans, map->stripes[i].dev,
1977 map->stripes[i].physical);
1980 if (map->stripes[i].dev) {
1981 ret = btrfs_update_device(trans, map->stripes[i].dev);
1985 ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
1990 trace_btrfs_chunk_free(root, map, chunk_offset, em->len);
1992 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
1993 ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset);
1997 ret = btrfs_remove_block_group(trans, extent_root, chunk_offset);
2000 write_lock(&em_tree->lock);
2001 remove_extent_mapping(em_tree, em);
2002 write_unlock(&em_tree->lock);
2007 /* once for the tree */
2008 free_extent_map(em);
2010 free_extent_map(em);
2012 unlock_chunks(root);
2013 btrfs_end_transaction(trans, root);
2017 static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
2019 struct btrfs_root *chunk_root = root->fs_info->chunk_root;
2020 struct btrfs_path *path;
2021 struct extent_buffer *leaf;
2022 struct btrfs_chunk *chunk;
2023 struct btrfs_key key;
2024 struct btrfs_key found_key;
2025 u64 chunk_tree = chunk_root->root_key.objectid;
2027 bool retried = false;
2031 path = btrfs_alloc_path();
2036 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2037 key.offset = (u64)-1;
2038 key.type = BTRFS_CHUNK_ITEM_KEY;
2041 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2046 ret = btrfs_previous_item(chunk_root, path, key.objectid,
2053 leaf = path->nodes[0];
2054 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2056 chunk = btrfs_item_ptr(leaf, path->slots[0],
2057 struct btrfs_chunk);
2058 chunk_type = btrfs_chunk_type(leaf, chunk);
2059 btrfs_release_path(path);
2061 if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM) {
2062 ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
2071 if (found_key.offset == 0)
2073 key.offset = found_key.offset - 1;
2076 if (failed && !retried) {
2080 } else if (failed && retried) {
2085 btrfs_free_path(path);
2089 static int insert_balance_item(struct btrfs_root *root,
2090 struct btrfs_balance_control *bctl)
2092 struct btrfs_trans_handle *trans;
2093 struct btrfs_balance_item *item;
2094 struct btrfs_disk_balance_args disk_bargs;
2095 struct btrfs_path *path;
2096 struct extent_buffer *leaf;
2097 struct btrfs_key key;
2100 path = btrfs_alloc_path();
2104 trans = btrfs_start_transaction(root, 0);
2105 if (IS_ERR(trans)) {
2106 btrfs_free_path(path);
2107 return PTR_ERR(trans);
2110 key.objectid = BTRFS_BALANCE_OBJECTID;
2111 key.type = BTRFS_BALANCE_ITEM_KEY;
2114 ret = btrfs_insert_empty_item(trans, root, path, &key,
2119 leaf = path->nodes[0];
2120 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2122 memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
2124 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->data);
2125 btrfs_set_balance_data(leaf, item, &disk_bargs);
2126 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->meta);
2127 btrfs_set_balance_meta(leaf, item, &disk_bargs);
2128 btrfs_cpu_balance_args_to_disk(&disk_bargs, &bctl->sys);
2129 btrfs_set_balance_sys(leaf, item, &disk_bargs);
2131 btrfs_set_balance_flags(leaf, item, bctl->flags);
2133 btrfs_mark_buffer_dirty(leaf);
2135 btrfs_free_path(path);
2136 err = btrfs_commit_transaction(trans, root);
2142 static int del_balance_item(struct btrfs_root *root)
2144 struct btrfs_trans_handle *trans;
2145 struct btrfs_path *path;
2146 struct btrfs_key key;
2149 path = btrfs_alloc_path();
2153 trans = btrfs_start_transaction(root, 0);
2154 if (IS_ERR(trans)) {
2155 btrfs_free_path(path);
2156 return PTR_ERR(trans);
2159 key.objectid = BTRFS_BALANCE_OBJECTID;
2160 key.type = BTRFS_BALANCE_ITEM_KEY;
2163 ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
2171 ret = btrfs_del_item(trans, root, path);
2173 btrfs_free_path(path);
2174 err = btrfs_commit_transaction(trans, root);
2181 * This is a heuristic used to reduce the number of chunks balanced on
2182 * resume after balance was interrupted.
2184 static void update_balance_args(struct btrfs_balance_control *bctl)
2187 * Turn on soft mode for chunk types that were being converted.
2189 if (bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)
2190 bctl->data.flags |= BTRFS_BALANCE_ARGS_SOFT;
2191 if (bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)
2192 bctl->sys.flags |= BTRFS_BALANCE_ARGS_SOFT;
2193 if (bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)
2194 bctl->meta.flags |= BTRFS_BALANCE_ARGS_SOFT;
2197 * Turn on usage filter if is not already used. The idea is
2198 * that chunks that we have already balanced should be
2199 * reasonably full. Don't do it for chunks that are being
2200 * converted - that will keep us from relocating unconverted
2201 * (albeit full) chunks.
2203 if (!(bctl->data.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2204 !(bctl->data.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2205 bctl->data.flags |= BTRFS_BALANCE_ARGS_USAGE;
2206 bctl->data.usage = 90;
2208 if (!(bctl->sys.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2209 !(bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2210 bctl->sys.flags |= BTRFS_BALANCE_ARGS_USAGE;
2211 bctl->sys.usage = 90;
2213 if (!(bctl->meta.flags & BTRFS_BALANCE_ARGS_USAGE) &&
2214 !(bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT)) {
2215 bctl->meta.flags |= BTRFS_BALANCE_ARGS_USAGE;
2216 bctl->meta.usage = 90;
2221 * Should be called with both balance and volume mutexes held to
2222 * serialize other volume operations (add_dev/rm_dev/resize) with
2223 * restriper. Same goes for unset_balance_control.
2225 static void set_balance_control(struct btrfs_balance_control *bctl)
2227 struct btrfs_fs_info *fs_info = bctl->fs_info;
2229 BUG_ON(fs_info->balance_ctl);
2231 spin_lock(&fs_info->balance_lock);
2232 fs_info->balance_ctl = bctl;
2233 spin_unlock(&fs_info->balance_lock);
2236 static void unset_balance_control(struct btrfs_fs_info *fs_info)
2238 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
2240 BUG_ON(!fs_info->balance_ctl);
2242 spin_lock(&fs_info->balance_lock);
2243 fs_info->balance_ctl = NULL;
2244 spin_unlock(&fs_info->balance_lock);
2250 * Balance filters. Return 1 if chunk should be filtered out
2251 * (should not be balanced).
2253 static int chunk_profiles_filter(u64 chunk_type,
2254 struct btrfs_balance_args *bargs)
2256 chunk_type = chunk_to_extended(chunk_type) &
2257 BTRFS_EXTENDED_PROFILE_MASK;
2259 if (bargs->profiles & chunk_type)
2265 static u64 div_factor_fine(u64 num, int factor)
2277 static int chunk_usage_filter(struct btrfs_fs_info *fs_info, u64 chunk_offset,
2278 struct btrfs_balance_args *bargs)
2280 struct btrfs_block_group_cache *cache;
2281 u64 chunk_used, user_thresh;
2284 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2285 chunk_used = btrfs_block_group_used(&cache->item);
2287 user_thresh = div_factor_fine(cache->key.offset, bargs->usage);
2288 if (chunk_used < user_thresh)
2291 btrfs_put_block_group(cache);
2295 static int chunk_devid_filter(struct extent_buffer *leaf,
2296 struct btrfs_chunk *chunk,
2297 struct btrfs_balance_args *bargs)
2299 struct btrfs_stripe *stripe;
2300 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2303 for (i = 0; i < num_stripes; i++) {
2304 stripe = btrfs_stripe_nr(chunk, i);
2305 if (btrfs_stripe_devid(leaf, stripe) == bargs->devid)
2312 /* [pstart, pend) */
2313 static int chunk_drange_filter(struct extent_buffer *leaf,
2314 struct btrfs_chunk *chunk,
2316 struct btrfs_balance_args *bargs)
2318 struct btrfs_stripe *stripe;
2319 int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
2325 if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))
2328 if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |
2329 BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10))
2333 factor = num_stripes / factor;
2335 for (i = 0; i < num_stripes; i++) {
2336 stripe = btrfs_stripe_nr(chunk, i);
2337 if (btrfs_stripe_devid(leaf, stripe) != bargs->devid)
2340 stripe_offset = btrfs_stripe_offset(leaf, stripe);
2341 stripe_length = btrfs_chunk_length(leaf, chunk);
2342 do_div(stripe_length, factor);
2344 if (stripe_offset < bargs->pend &&
2345 stripe_offset + stripe_length > bargs->pstart)
2352 /* [vstart, vend) */
2353 static int chunk_vrange_filter(struct extent_buffer *leaf,
2354 struct btrfs_chunk *chunk,
2356 struct btrfs_balance_args *bargs)
2358 if (chunk_offset < bargs->vend &&
2359 chunk_offset + btrfs_chunk_length(leaf, chunk) > bargs->vstart)
2360 /* at least part of the chunk is inside this vrange */
2366 static int chunk_soft_convert_filter(u64 chunk_type,
2367 struct btrfs_balance_args *bargs)
2369 if (!(bargs->flags & BTRFS_BALANCE_ARGS_CONVERT))
2372 chunk_type = chunk_to_extended(chunk_type) &
2373 BTRFS_EXTENDED_PROFILE_MASK;
2375 if (bargs->target == chunk_type)
2381 static int should_balance_chunk(struct btrfs_root *root,
2382 struct extent_buffer *leaf,
2383 struct btrfs_chunk *chunk, u64 chunk_offset)
2385 struct btrfs_balance_control *bctl = root->fs_info->balance_ctl;
2386 struct btrfs_balance_args *bargs = NULL;
2387 u64 chunk_type = btrfs_chunk_type(leaf, chunk);
2390 if (!((chunk_type & BTRFS_BLOCK_GROUP_TYPE_MASK) &
2391 (bctl->flags & BTRFS_BALANCE_TYPE_MASK))) {
2395 if (chunk_type & BTRFS_BLOCK_GROUP_DATA)
2396 bargs = &bctl->data;
2397 else if (chunk_type & BTRFS_BLOCK_GROUP_SYSTEM)
2399 else if (chunk_type & BTRFS_BLOCK_GROUP_METADATA)
2400 bargs = &bctl->meta;
2402 /* profiles filter */
2403 if ((bargs->flags & BTRFS_BALANCE_ARGS_PROFILES) &&
2404 chunk_profiles_filter(chunk_type, bargs)) {
2409 if ((bargs->flags & BTRFS_BALANCE_ARGS_USAGE) &&
2410 chunk_usage_filter(bctl->fs_info, chunk_offset, bargs)) {
2415 if ((bargs->flags & BTRFS_BALANCE_ARGS_DEVID) &&
2416 chunk_devid_filter(leaf, chunk, bargs)) {
2420 /* drange filter, makes sense only with devid filter */
2421 if ((bargs->flags & BTRFS_BALANCE_ARGS_DRANGE) &&
2422 chunk_drange_filter(leaf, chunk, chunk_offset, bargs)) {
2427 if ((bargs->flags & BTRFS_BALANCE_ARGS_VRANGE) &&
2428 chunk_vrange_filter(leaf, chunk, chunk_offset, bargs)) {
2432 /* soft profile changing mode */
2433 if ((bargs->flags & BTRFS_BALANCE_ARGS_SOFT) &&
2434 chunk_soft_convert_filter(chunk_type, bargs)) {
2441 static u64 div_factor(u64 num, int factor)
2450 static int __btrfs_balance(struct btrfs_fs_info *fs_info)
2452 struct btrfs_balance_control *bctl = fs_info->balance_ctl;
2453 struct btrfs_root *chunk_root = fs_info->chunk_root;
2454 struct btrfs_root *dev_root = fs_info->dev_root;
2455 struct list_head *devices;
2456 struct btrfs_device *device;
2459 struct btrfs_chunk *chunk;
2460 struct btrfs_path *path;
2461 struct btrfs_key key;
2462 struct btrfs_key found_key;
2463 struct btrfs_trans_handle *trans;
2464 struct extent_buffer *leaf;
2467 int enospc_errors = 0;
2468 bool counting = true;
2470 /* step one make some room on all the devices */
2471 devices = &fs_info->fs_devices->devices;
2472 list_for_each_entry(device, devices, dev_list) {
2473 old_size = device->total_bytes;
2474 size_to_free = div_factor(old_size, 1);
2475 size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
2476 if (!device->writeable ||
2477 device->total_bytes - device->bytes_used > size_to_free)
2480 ret = btrfs_shrink_device(device, old_size - size_to_free);
2485 trans = btrfs_start_transaction(dev_root, 0);
2486 BUG_ON(IS_ERR(trans));
2488 ret = btrfs_grow_device(trans, device, old_size);
2491 btrfs_end_transaction(trans, dev_root);
2494 /* step two, relocate all the chunks */
2495 path = btrfs_alloc_path();
2501 /* zero out stat counters */
2502 spin_lock(&fs_info->balance_lock);
2503 memset(&bctl->stat, 0, sizeof(bctl->stat));
2504 spin_unlock(&fs_info->balance_lock);
2506 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
2507 key.offset = (u64)-1;
2508 key.type = BTRFS_CHUNK_ITEM_KEY;
2511 if ((!counting && atomic_read(&fs_info->balance_pause_req)) ||
2512 atomic_read(&fs_info->balance_cancel_req)) {
2517 ret = btrfs_search_slot(NULL, chunk_root, &key, path, 0, 0);
2522 * this shouldn't happen, it means the last relocate
2526 BUG(); /* FIXME break ? */
2528 ret = btrfs_previous_item(chunk_root, path, 0,
2529 BTRFS_CHUNK_ITEM_KEY);
2535 leaf = path->nodes[0];
2536 slot = path->slots[0];
2537 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2539 if (found_key.objectid != key.objectid)
2542 /* chunk zero is special */
2543 if (found_key.offset == 0)
2546 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
2549 spin_lock(&fs_info->balance_lock);
2550 bctl->stat.considered++;
2551 spin_unlock(&fs_info->balance_lock);
2554 ret = should_balance_chunk(chunk_root, leaf, chunk,
2556 btrfs_release_path(path);
2561 spin_lock(&fs_info->balance_lock);
2562 bctl->stat.expected++;
2563 spin_unlock(&fs_info->balance_lock);
2567 ret = btrfs_relocate_chunk(chunk_root,
2568 chunk_root->root_key.objectid,
2571 if (ret && ret != -ENOSPC)
2573 if (ret == -ENOSPC) {
2576 spin_lock(&fs_info->balance_lock);
2577 bctl->stat.completed++;
2578 spin_unlock(&fs_info->balance_lock);
2581 key.offset = found_key.offset - 1;
2585 btrfs_release_path(path);
2590 btrfs_free_path(path);
2591 if (enospc_errors) {
2592 printk(KERN_INFO "btrfs: %d enospc errors during balance\n",
2601 static inline int balance_need_close(struct btrfs_fs_info *fs_info)
2603 /* cancel requested || normal exit path */
2604 return atomic_read(&fs_info->balance_cancel_req) ||
2605 (atomic_read(&fs_info->balance_pause_req) == 0 &&
2606 atomic_read(&fs_info->balance_cancel_req) == 0);
2609 static void __cancel_balance(struct btrfs_fs_info *fs_info)
2613 unset_balance_control(fs_info);
2614 ret = del_balance_item(fs_info->tree_root);
2618 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
2619 struct btrfs_ioctl_balance_args *bargs);
2622 * Should be called with both balance and volume mutexes held
2624 int btrfs_balance(struct btrfs_balance_control *bctl,
2625 struct btrfs_ioctl_balance_args *bargs)
2627 struct btrfs_fs_info *fs_info = bctl->fs_info;
2631 if (btrfs_fs_closing(fs_info) ||
2632 atomic_read(&fs_info->balance_pause_req) ||
2633 atomic_read(&fs_info->balance_cancel_req)) {
2639 * In case of mixed groups both data and meta should be picked,
2640 * and identical options should be given for both of them.
2642 allowed = btrfs_super_incompat_flags(fs_info->super_copy);
2643 if ((allowed & BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS) &&
2644 (bctl->flags & (BTRFS_BALANCE_DATA | BTRFS_BALANCE_METADATA))) {
2645 if (!(bctl->flags & BTRFS_BALANCE_DATA) ||
2646 !(bctl->flags & BTRFS_BALANCE_METADATA) ||
2647 memcmp(&bctl->data, &bctl->meta, sizeof(bctl->data))) {
2648 printk(KERN_ERR "btrfs: with mixed groups data and "
2649 "metadata balance options must be the same\n");
2656 * Profile changing sanity checks. Skip them if a simple
2657 * balance is requested.
2659 if (!((bctl->data.flags | bctl->sys.flags | bctl->meta.flags) &
2660 BTRFS_BALANCE_ARGS_CONVERT))
2663 allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
2664 if (fs_info->fs_devices->num_devices == 1)
2665 allowed |= BTRFS_BLOCK_GROUP_DUP;
2666 else if (fs_info->fs_devices->num_devices < 4)
2667 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
2669 allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
2670 BTRFS_BLOCK_GROUP_RAID10);
2672 if (!alloc_profile_is_valid(bctl->data.target, 1) ||
2673 bctl->data.target & ~allowed) {
2674 printk(KERN_ERR "btrfs: unable to start balance with target "
2675 "data profile %llu\n",
2676 (unsigned long long)bctl->data.target);
2680 if (!alloc_profile_is_valid(bctl->meta.target, 1) ||
2681 bctl->meta.target & ~allowed) {
2682 printk(KERN_ERR "btrfs: unable to start balance with target "
2683 "metadata profile %llu\n",
2684 (unsigned long long)bctl->meta.target);
2688 if (!alloc_profile_is_valid(bctl->sys.target, 1) ||
2689 bctl->sys.target & ~allowed) {
2690 printk(KERN_ERR "btrfs: unable to start balance with target "
2691 "system profile %llu\n",
2692 (unsigned long long)bctl->sys.target);
2697 if (bctl->data.target & BTRFS_BLOCK_GROUP_DUP) {
2698 printk(KERN_ERR "btrfs: dup for data is not allowed\n");
2703 /* allow to reduce meta or sys integrity only if force set */
2704 allowed = BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1 |
2705 BTRFS_BLOCK_GROUP_RAID10;
2706 if (((bctl->sys.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
2707 (fs_info->avail_system_alloc_bits & allowed) &&
2708 !(bctl->sys.target & allowed)) ||
2709 ((bctl->meta.flags & BTRFS_BALANCE_ARGS_CONVERT) &&
2710 (fs_info->avail_metadata_alloc_bits & allowed) &&
2711 !(bctl->meta.target & allowed))) {
2712 if (bctl->flags & BTRFS_BALANCE_FORCE) {
2713 printk(KERN_INFO "btrfs: force reducing metadata "
2716 printk(KERN_ERR "btrfs: balance will reduce metadata "
2717 "integrity, use force if you want this\n");
2724 ret = insert_balance_item(fs_info->tree_root, bctl);
2725 if (ret && ret != -EEXIST)
2728 if (!(bctl->flags & BTRFS_BALANCE_RESUME)) {
2729 BUG_ON(ret == -EEXIST);
2730 set_balance_control(bctl);
2732 BUG_ON(ret != -EEXIST);
2733 spin_lock(&fs_info->balance_lock);
2734 update_balance_args(bctl);
2735 spin_unlock(&fs_info->balance_lock);
2738 atomic_inc(&fs_info->balance_running);
2739 mutex_unlock(&fs_info->balance_mutex);
2741 ret = __btrfs_balance(fs_info);
2743 mutex_lock(&fs_info->balance_mutex);
2744 atomic_dec(&fs_info->balance_running);
2747 memset(bargs, 0, sizeof(*bargs));
2748 update_ioctl_balance_args(fs_info, 0, bargs);
2751 if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
2752 balance_need_close(fs_info)) {
2753 __cancel_balance(fs_info);
2756 wake_up(&fs_info->balance_wait_q);
2760 if (bctl->flags & BTRFS_BALANCE_RESUME)
2761 __cancel_balance(fs_info);
2767 static int balance_kthread(void *data)
2769 struct btrfs_balance_control *bctl =
2770 (struct btrfs_balance_control *)data;
2771 struct btrfs_fs_info *fs_info = bctl->fs_info;
2774 mutex_lock(&fs_info->volume_mutex);
2775 mutex_lock(&fs_info->balance_mutex);
2777 set_balance_control(bctl);
2779 if (btrfs_test_opt(fs_info->tree_root, SKIP_BALANCE)) {
2780 printk(KERN_INFO "btrfs: force skipping balance\n");
2782 printk(KERN_INFO "btrfs: continuing balance\n");
2783 ret = btrfs_balance(bctl, NULL);
2786 mutex_unlock(&fs_info->balance_mutex);
2787 mutex_unlock(&fs_info->volume_mutex);
2791 int btrfs_recover_balance(struct btrfs_root *tree_root)
2793 struct task_struct *tsk;
2794 struct btrfs_balance_control *bctl;
2795 struct btrfs_balance_item *item;
2796 struct btrfs_disk_balance_args disk_bargs;
2797 struct btrfs_path *path;
2798 struct extent_buffer *leaf;
2799 struct btrfs_key key;
2802 path = btrfs_alloc_path();
2806 bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
2812 key.objectid = BTRFS_BALANCE_OBJECTID;
2813 key.type = BTRFS_BALANCE_ITEM_KEY;
2816 ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
2819 if (ret > 0) { /* ret = -ENOENT; */
2824 leaf = path->nodes[0];
2825 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_balance_item);
2827 bctl->fs_info = tree_root->fs_info;
2828 bctl->flags = btrfs_balance_flags(leaf, item) | BTRFS_BALANCE_RESUME;
2830 btrfs_balance_data(leaf, item, &disk_bargs);
2831 btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
2832 btrfs_balance_meta(leaf, item, &disk_bargs);
2833 btrfs_disk_balance_args_to_cpu(&bctl->meta, &disk_bargs);
2834 btrfs_balance_sys(leaf, item, &disk_bargs);
2835 btrfs_disk_balance_args_to_cpu(&bctl->sys, &disk_bargs);
2837 tsk = kthread_run(balance_kthread, bctl, "btrfs-balance");
2846 btrfs_free_path(path);
2850 int btrfs_pause_balance(struct btrfs_fs_info *fs_info)
2854 mutex_lock(&fs_info->balance_mutex);
2855 if (!fs_info->balance_ctl) {
2856 mutex_unlock(&fs_info->balance_mutex);
2860 if (atomic_read(&fs_info->balance_running)) {
2861 atomic_inc(&fs_info->balance_pause_req);
2862 mutex_unlock(&fs_info->balance_mutex);
2864 wait_event(fs_info->balance_wait_q,
2865 atomic_read(&fs_info->balance_running) == 0);
2867 mutex_lock(&fs_info->balance_mutex);
2868 /* we are good with balance_ctl ripped off from under us */
2869 BUG_ON(atomic_read(&fs_info->balance_running));
2870 atomic_dec(&fs_info->balance_pause_req);
2875 mutex_unlock(&fs_info->balance_mutex);
2879 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info)
2881 mutex_lock(&fs_info->balance_mutex);
2882 if (!fs_info->balance_ctl) {
2883 mutex_unlock(&fs_info->balance_mutex);
2887 atomic_inc(&fs_info->balance_cancel_req);
2889 * if we are running just wait and return, balance item is
2890 * deleted in btrfs_balance in this case
2892 if (atomic_read(&fs_info->balance_running)) {
2893 mutex_unlock(&fs_info->balance_mutex);
2894 wait_event(fs_info->balance_wait_q,
2895 atomic_read(&fs_info->balance_running) == 0);
2896 mutex_lock(&fs_info->balance_mutex);
2898 /* __cancel_balance needs volume_mutex */
2899 mutex_unlock(&fs_info->balance_mutex);
2900 mutex_lock(&fs_info->volume_mutex);
2901 mutex_lock(&fs_info->balance_mutex);
2903 if (fs_info->balance_ctl)
2904 __cancel_balance(fs_info);
2906 mutex_unlock(&fs_info->volume_mutex);
2909 BUG_ON(fs_info->balance_ctl || atomic_read(&fs_info->balance_running));
2910 atomic_dec(&fs_info->balance_cancel_req);
2911 mutex_unlock(&fs_info->balance_mutex);
2916 * shrinking a device means finding all of the device extents past
2917 * the new size, and then following the back refs to the chunks.
2918 * The chunk relocation code actually frees the device extent
2920 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
2922 struct btrfs_trans_handle *trans;
2923 struct btrfs_root *root = device->dev_root;
2924 struct btrfs_dev_extent *dev_extent = NULL;
2925 struct btrfs_path *path;
2933 bool retried = false;
2934 struct extent_buffer *l;
2935 struct btrfs_key key;
2936 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
2937 u64 old_total = btrfs_super_total_bytes(super_copy);
2938 u64 old_size = device->total_bytes;
2939 u64 diff = device->total_bytes - new_size;
2941 if (new_size >= device->total_bytes)
2944 path = btrfs_alloc_path();
2952 device->total_bytes = new_size;
2953 if (device->writeable) {
2954 device->fs_devices->total_rw_bytes -= diff;
2955 spin_lock(&root->fs_info->free_chunk_lock);
2956 root->fs_info->free_chunk_space -= diff;
2957 spin_unlock(&root->fs_info->free_chunk_lock);
2959 unlock_chunks(root);
2962 key.objectid = device->devid;
2963 key.offset = (u64)-1;
2964 key.type = BTRFS_DEV_EXTENT_KEY;
2967 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2971 ret = btrfs_previous_item(root, path, 0, key.type);
2976 btrfs_release_path(path);
2981 slot = path->slots[0];
2982 btrfs_item_key_to_cpu(l, &key, path->slots[0]);
2984 if (key.objectid != device->devid) {
2985 btrfs_release_path(path);
2989 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
2990 length = btrfs_dev_extent_length(l, dev_extent);
2992 if (key.offset + length <= new_size) {
2993 btrfs_release_path(path);
2997 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
2998 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
2999 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
3000 btrfs_release_path(path);
3002 ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
3004 if (ret && ret != -ENOSPC)
3011 if (failed && !retried) {
3015 } else if (failed && retried) {
3019 device->total_bytes = old_size;
3020 if (device->writeable)
3021 device->fs_devices->total_rw_bytes += diff;
3022 spin_lock(&root->fs_info->free_chunk_lock);
3023 root->fs_info->free_chunk_space += diff;
3024 spin_unlock(&root->fs_info->free_chunk_lock);
3025 unlock_chunks(root);
3029 /* Shrinking succeeded, else we would be at "done". */
3030 trans = btrfs_start_transaction(root, 0);
3031 if (IS_ERR(trans)) {
3032 ret = PTR_ERR(trans);
3038 device->disk_total_bytes = new_size;
3039 /* Now btrfs_update_device() will change the on-disk size. */
3040 ret = btrfs_update_device(trans, device);
3042 unlock_chunks(root);
3043 btrfs_end_transaction(trans, root);
3046 WARN_ON(diff > old_total);
3047 btrfs_set_super_total_bytes(super_copy, old_total - diff);
3048 unlock_chunks(root);
3049 btrfs_end_transaction(trans, root);
3051 btrfs_free_path(path);
3055 static int btrfs_add_system_chunk(struct btrfs_root *root,
3056 struct btrfs_key *key,
3057 struct btrfs_chunk *chunk, int item_size)
3059 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
3060 struct btrfs_disk_key disk_key;
3064 array_size = btrfs_super_sys_array_size(super_copy);
3065 if (array_size + item_size > BTRFS_SYSTEM_CHUNK_ARRAY_SIZE)
3068 ptr = super_copy->sys_chunk_array + array_size;
3069 btrfs_cpu_key_to_disk(&disk_key, key);
3070 memcpy(ptr, &disk_key, sizeof(disk_key));
3071 ptr += sizeof(disk_key);
3072 memcpy(ptr, chunk, item_size);
3073 item_size += sizeof(disk_key);
3074 btrfs_set_super_sys_array_size(super_copy, array_size + item_size);
3079 * sort the devices in descending order by max_avail, total_avail
3081 static int btrfs_cmp_device_info(const void *a, const void *b)
3083 const struct btrfs_device_info *di_a = a;
3084 const struct btrfs_device_info *di_b = b;
3086 if (di_a->max_avail > di_b->max_avail)
3088 if (di_a->max_avail < di_b->max_avail)
3090 if (di_a->total_avail > di_b->total_avail)
3092 if (di_a->total_avail < di_b->total_avail)
3097 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
3098 struct btrfs_root *extent_root,
3099 struct map_lookup **map_ret,
3100 u64 *num_bytes_out, u64 *stripe_size_out,
3101 u64 start, u64 type)
3103 struct btrfs_fs_info *info = extent_root->fs_info;
3104 struct btrfs_fs_devices *fs_devices = info->fs_devices;
3105 struct list_head *cur;
3106 struct map_lookup *map = NULL;
3107 struct extent_map_tree *em_tree;
3108 struct extent_map *em;
3109 struct btrfs_device_info *devices_info = NULL;
3111 int num_stripes; /* total number of stripes to allocate */
3112 int sub_stripes; /* sub_stripes info for map */
3113 int dev_stripes; /* stripes per dev */
3114 int devs_max; /* max devs to use */
3115 int devs_min; /* min devs needed */
3116 int devs_increment; /* ndevs has to be a multiple of this */
3117 int ncopies; /* how many copies to data has */
3119 u64 max_stripe_size;
3127 if ((type & BTRFS_BLOCK_GROUP_RAID1) &&
3128 (type & BTRFS_BLOCK_GROUP_DUP)) {
3130 type &= ~BTRFS_BLOCK_GROUP_DUP;
3133 if (list_empty(&fs_devices->alloc_list))
3140 devs_max = 0; /* 0 == as many as possible */
3144 * define the properties of each RAID type.
3145 * FIXME: move this to a global table and use it in all RAID
3148 if (type & (BTRFS_BLOCK_GROUP_DUP)) {
3152 } else if (type & (BTRFS_BLOCK_GROUP_RAID0)) {
3154 } else if (type & (BTRFS_BLOCK_GROUP_RAID1)) {
3159 } else if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
3168 if (type & BTRFS_BLOCK_GROUP_DATA) {
3169 max_stripe_size = 1024 * 1024 * 1024;
3170 max_chunk_size = 10 * max_stripe_size;
3171 } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
3172 /* for larger filesystems, use larger metadata chunks */
3173 if (fs_devices->total_rw_bytes > 50ULL * 1024 * 1024 * 1024)
3174 max_stripe_size = 1024 * 1024 * 1024;
3176 max_stripe_size = 256 * 1024 * 1024;
3177 max_chunk_size = max_stripe_size;
3178 } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
3179 max_stripe_size = 32 * 1024 * 1024;
3180 max_chunk_size = 2 * max_stripe_size;
3182 printk(KERN_ERR "btrfs: invalid chunk type 0x%llx requested\n",
3187 /* we don't want a chunk larger than 10% of writeable space */
3188 max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
3191 devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices,
3196 cur = fs_devices->alloc_list.next;
3199 * in the first pass through the devices list, we gather information
3200 * about the available holes on each device.
3203 while (cur != &fs_devices->alloc_list) {
3204 struct btrfs_device *device;
3208 device = list_entry(cur, struct btrfs_device, dev_alloc_list);
3212 if (!device->writeable) {
3214 "btrfs: read-only device in alloc_list\n");
3219 if (!device->in_fs_metadata)
3222 if (device->total_bytes > device->bytes_used)
3223 total_avail = device->total_bytes - device->bytes_used;
3227 /* If there is no space on this device, skip it. */
3228 if (total_avail == 0)
3231 ret = find_free_dev_extent(device,
3232 max_stripe_size * dev_stripes,
3233 &dev_offset, &max_avail);
3234 if (ret && ret != -ENOSPC)
3238 max_avail = max_stripe_size * dev_stripes;
3240 if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
3243 devices_info[ndevs].dev_offset = dev_offset;
3244 devices_info[ndevs].max_avail = max_avail;
3245 devices_info[ndevs].total_avail = total_avail;
3246 devices_info[ndevs].dev = device;
3251 * now sort the devices by hole size / available space
3253 sort(devices_info, ndevs, sizeof(struct btrfs_device_info),
3254 btrfs_cmp_device_info, NULL);
3256 /* round down to number of usable stripes */
3257 ndevs -= ndevs % devs_increment;
3259 if (ndevs < devs_increment * sub_stripes || ndevs < devs_min) {
3264 if (devs_max && ndevs > devs_max)
3267 * the primary goal is to maximize the number of stripes, so use as many
3268 * devices as possible, even if the stripes are not maximum sized.
3270 stripe_size = devices_info[ndevs-1].max_avail;
3271 num_stripes = ndevs * dev_stripes;
3273 if (stripe_size * num_stripes > max_chunk_size * ncopies) {
3274 stripe_size = max_chunk_size * ncopies;
3275 do_div(stripe_size, num_stripes);
3278 do_div(stripe_size, dev_stripes);
3279 do_div(stripe_size, BTRFS_STRIPE_LEN);
3280 stripe_size *= BTRFS_STRIPE_LEN;
3282 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
3287 map->num_stripes = num_stripes;
3289 for (i = 0; i < ndevs; ++i) {
3290 for (j = 0; j < dev_stripes; ++j) {
3291 int s = i * dev_stripes + j;
3292 map->stripes[s].dev = devices_info[i].dev;
3293 map->stripes[s].physical = devices_info[i].dev_offset +
3297 map->sector_size = extent_root->sectorsize;
3298 map->stripe_len = BTRFS_STRIPE_LEN;
3299 map->io_align = BTRFS_STRIPE_LEN;
3300 map->io_width = BTRFS_STRIPE_LEN;
3302 map->sub_stripes = sub_stripes;
3305 num_bytes = stripe_size * (num_stripes / ncopies);
3307 *stripe_size_out = stripe_size;
3308 *num_bytes_out = num_bytes;
3310 trace_btrfs_chunk_alloc(info->chunk_root, map, start, num_bytes);
3312 em = alloc_extent_map();
3317 em->bdev = (struct block_device *)map;
3319 em->len = num_bytes;
3320 em->block_start = 0;
3321 em->block_len = em->len;
3323 em_tree = &extent_root->fs_info->mapping_tree.map_tree;
3324 write_lock(&em_tree->lock);
3325 ret = add_extent_mapping(em_tree, em);
3326 write_unlock(&em_tree->lock);
3328 free_extent_map(em);
3330 ret = btrfs_make_block_group(trans, extent_root, 0, type,
3331 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
3335 for (i = 0; i < map->num_stripes; ++i) {
3336 struct btrfs_device *device;
3339 device = map->stripes[i].dev;
3340 dev_offset = map->stripes[i].physical;
3342 ret = btrfs_alloc_dev_extent(trans, device,
3343 info->chunk_root->root_key.objectid,
3344 BTRFS_FIRST_CHUNK_TREE_OBJECTID,
3345 start, dev_offset, stripe_size);
3349 kfree(devices_info);
3354 kfree(devices_info);
3358 static int __finish_chunk_alloc(struct btrfs_trans_handle *trans,
3359 struct btrfs_root *extent_root,
3360 struct map_lookup *map, u64 chunk_offset,
3361 u64 chunk_size, u64 stripe_size)
3364 struct btrfs_key key;
3365 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
3366 struct btrfs_device *device;
3367 struct btrfs_chunk *chunk;
3368 struct btrfs_stripe *stripe;
3369 size_t item_size = btrfs_chunk_item_size(map->num_stripes);
3373 chunk = kzalloc(item_size, GFP_NOFS);
3378 while (index < map->num_stripes) {
3379 device = map->stripes[index].dev;
3380 device->bytes_used += stripe_size;
3381 ret = btrfs_update_device(trans, device);
3386 spin_lock(&extent_root->fs_info->free_chunk_lock);
3387 extent_root->fs_info->free_chunk_space -= (stripe_size *
3389 spin_unlock(&extent_root->fs_info->free_chunk_lock);
3392 stripe = &chunk->stripe;
3393 while (index < map->num_stripes) {
3394 device = map->stripes[index].dev;
3395 dev_offset = map->stripes[index].physical;
3397 btrfs_set_stack_stripe_devid(stripe, device->devid);
3398 btrfs_set_stack_stripe_offset(stripe, dev_offset);
3399 memcpy(stripe->dev_uuid, device->uuid, BTRFS_UUID_SIZE);
3404 btrfs_set_stack_chunk_length(chunk, chunk_size);
3405 btrfs_set_stack_chunk_owner(chunk, extent_root->root_key.objectid);
3406 btrfs_set_stack_chunk_stripe_len(chunk, map->stripe_len);
3407 btrfs_set_stack_chunk_type(chunk, map->type);
3408 btrfs_set_stack_chunk_num_stripes(chunk, map->num_stripes);
3409 btrfs_set_stack_chunk_io_align(chunk, map->stripe_len);
3410 btrfs_set_stack_chunk_io_width(chunk, map->stripe_len);
3411 btrfs_set_stack_chunk_sector_size(chunk, extent_root->sectorsize);
3412 btrfs_set_stack_chunk_sub_stripes(chunk, map->sub_stripes);
3414 key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
3415 key.type = BTRFS_CHUNK_ITEM_KEY;
3416 key.offset = chunk_offset;
3418 ret = btrfs_insert_item(trans, chunk_root, &key, chunk, item_size);
3421 if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) {
3422 ret = btrfs_add_system_chunk(chunk_root, &key, chunk,
3432 * Chunk allocation falls into two parts. The first part does works
3433 * that make the new allocated chunk useable, but not do any operation
3434 * that modifies the chunk tree. The second part does the works that
3435 * require modifying the chunk tree. This division is important for the
3436 * bootstrap process of adding storage to a seed btrfs.
3438 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
3439 struct btrfs_root *extent_root, u64 type)
3444 struct map_lookup *map;
3445 struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
3448 ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID,
3453 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
3454 &stripe_size, chunk_offset, type);
3458 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
3459 chunk_size, stripe_size);
3464 static noinline int init_first_rw_device(struct btrfs_trans_handle *trans,
3465 struct btrfs_root *root,
3466 struct btrfs_device *device)
3469 u64 sys_chunk_offset;
3473 u64 sys_stripe_size;
3475 struct map_lookup *map;
3476 struct map_lookup *sys_map;
3477 struct btrfs_fs_info *fs_info = root->fs_info;
3478 struct btrfs_root *extent_root = fs_info->extent_root;
3481 ret = find_next_chunk(fs_info->chunk_root,
3482 BTRFS_FIRST_CHUNK_TREE_OBJECTID, &chunk_offset);
3486 alloc_profile = BTRFS_BLOCK_GROUP_METADATA |
3487 fs_info->avail_metadata_alloc_bits;
3488 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
3490 ret = __btrfs_alloc_chunk(trans, extent_root, &map, &chunk_size,
3491 &stripe_size, chunk_offset, alloc_profile);
3494 sys_chunk_offset = chunk_offset + chunk_size;
3496 alloc_profile = BTRFS_BLOCK_GROUP_SYSTEM |
3497 fs_info->avail_system_alloc_bits;
3498 alloc_profile = btrfs_reduce_alloc_profile(root, alloc_profile);
3500 ret = __btrfs_alloc_chunk(trans, extent_root, &sys_map,
3501 &sys_chunk_size, &sys_stripe_size,
3502 sys_chunk_offset, alloc_profile);
3505 ret = btrfs_add_device(trans, fs_info->chunk_root, device);
3509 * Modifying chunk tree needs allocating new blocks from both
3510 * system block group and metadata block group. So we only can
3511 * do operations require modifying the chunk tree after both
3512 * block groups were created.
3514 ret = __finish_chunk_alloc(trans, extent_root, map, chunk_offset,
3515 chunk_size, stripe_size);
3518 ret = __finish_chunk_alloc(trans, extent_root, sys_map,
3519 sys_chunk_offset, sys_chunk_size,
3525 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
3527 struct extent_map *em;
3528 struct map_lookup *map;
3529 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
3533 read_lock(&map_tree->map_tree.lock);
3534 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
3535 read_unlock(&map_tree->map_tree.lock);
3539 if (btrfs_test_opt(root, DEGRADED)) {
3540 free_extent_map(em);
3544 map = (struct map_lookup *)em->bdev;
3545 for (i = 0; i < map->num_stripes; i++) {
3546 if (!map->stripes[i].dev->writeable) {
3551 free_extent_map(em);
3555 void btrfs_mapping_init(struct btrfs_mapping_tree *tree)
3557 extent_map_tree_init(&tree->map_tree);
3560 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
3562 struct extent_map *em;
3565 write_lock(&tree->map_tree.lock);
3566 em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
3568 remove_extent_mapping(&tree->map_tree, em);
3569 write_unlock(&tree->map_tree.lock);
3574 free_extent_map(em);
3575 /* once for the tree */
3576 free_extent_map(em);
3580 int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
3582 struct extent_map *em;
3583 struct map_lookup *map;
3584 struct extent_map_tree *em_tree = &map_tree->map_tree;
3587 read_lock(&em_tree->lock);
3588 em = lookup_extent_mapping(em_tree, logical, len);
3589 read_unlock(&em_tree->lock);
3592 BUG_ON(em->start > logical || em->start + em->len < logical);
3593 map = (struct map_lookup *)em->bdev;
3594 if (map->type & (BTRFS_BLOCK_GROUP_DUP | BTRFS_BLOCK_GROUP_RAID1))
3595 ret = map->num_stripes;
3596 else if (map->type & BTRFS_BLOCK_GROUP_RAID10)
3597 ret = map->sub_stripes;
3600 free_extent_map(em);
3604 static int find_live_mirror(struct map_lookup *map, int first, int num,
3608 if (map->stripes[optimal].dev->bdev)
3610 for (i = first; i < first + num; i++) {
3611 if (map->stripes[i].dev->bdev)
3614 /* we couldn't find one that doesn't fail. Just return something
3615 * and the io error handling code will clean up eventually
3620 static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
3621 u64 logical, u64 *length,
3622 struct btrfs_bio **bbio_ret,
3625 struct extent_map *em;
3626 struct map_lookup *map;
3627 struct extent_map_tree *em_tree = &map_tree->map_tree;
3630 u64 stripe_end_offset;
3639 struct btrfs_bio *bbio = NULL;
3641 read_lock(&em_tree->lock);
3642 em = lookup_extent_mapping(em_tree, logical, *length);
3643 read_unlock(&em_tree->lock);
3646 printk(KERN_CRIT "unable to find logical %llu len %llu\n",
3647 (unsigned long long)logical,
3648 (unsigned long long)*length);
3652 BUG_ON(em->start > logical || em->start + em->len < logical);
3653 map = (struct map_lookup *)em->bdev;
3654 offset = logical - em->start;
3656 if (mirror_num > map->num_stripes)
3661 * stripe_nr counts the total number of stripes we have to stride
3662 * to get to this block
3664 do_div(stripe_nr, map->stripe_len);
3666 stripe_offset = stripe_nr * map->stripe_len;
3667 BUG_ON(offset < stripe_offset);
3669 /* stripe_offset is the offset of this block in its stripe*/
3670 stripe_offset = offset - stripe_offset;
3672 if (rw & REQ_DISCARD)
3673 *length = min_t(u64, em->len - offset, *length);
3674 else if (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
3675 /* we limit the length of each bio to what fits in a stripe */
3676 *length = min_t(u64, em->len - offset,
3677 map->stripe_len - stripe_offset);
3679 *length = em->len - offset;
3687 stripe_nr_orig = stripe_nr;
3688 stripe_nr_end = (offset + *length + map->stripe_len - 1) &
3689 (~(map->stripe_len - 1));
3690 do_div(stripe_nr_end, map->stripe_len);
3691 stripe_end_offset = stripe_nr_end * map->stripe_len -
3693 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
3694 if (rw & REQ_DISCARD)
3695 num_stripes = min_t(u64, map->num_stripes,
3696 stripe_nr_end - stripe_nr_orig);
3697 stripe_index = do_div(stripe_nr, map->num_stripes);
3698 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
3699 if (rw & (REQ_WRITE | REQ_DISCARD))
3700 num_stripes = map->num_stripes;
3701 else if (mirror_num)
3702 stripe_index = mirror_num - 1;
3704 stripe_index = find_live_mirror(map, 0,
3706 current->pid % map->num_stripes);
3707 mirror_num = stripe_index + 1;
3710 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
3711 if (rw & (REQ_WRITE | REQ_DISCARD)) {
3712 num_stripes = map->num_stripes;
3713 } else if (mirror_num) {
3714 stripe_index = mirror_num - 1;
3719 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
3720 int factor = map->num_stripes / map->sub_stripes;
3722 stripe_index = do_div(stripe_nr, factor);
3723 stripe_index *= map->sub_stripes;
3726 num_stripes = map->sub_stripes;
3727 else if (rw & REQ_DISCARD)
3728 num_stripes = min_t(u64, map->sub_stripes *
3729 (stripe_nr_end - stripe_nr_orig),
3731 else if (mirror_num)
3732 stripe_index += mirror_num - 1;
3734 stripe_index = find_live_mirror(map, stripe_index,
3735 map->sub_stripes, stripe_index +
3736 current->pid % map->sub_stripes);
3737 mirror_num = stripe_index + 1;
3741 * after this do_div call, stripe_nr is the number of stripes
3742 * on this device we have to walk to find the data, and
3743 * stripe_index is the number of our device in the stripe array
3745 stripe_index = do_div(stripe_nr, map->num_stripes);
3746 mirror_num = stripe_index + 1;
3748 BUG_ON(stripe_index >= map->num_stripes);
3750 bbio = kzalloc(btrfs_bio_size(num_stripes), GFP_NOFS);
3755 atomic_set(&bbio->error, 0);
3757 if (rw & REQ_DISCARD) {
3759 int sub_stripes = 0;
3760 u64 stripes_per_dev = 0;
3761 u32 remaining_stripes = 0;
3764 (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
3765 if (map->type & BTRFS_BLOCK_GROUP_RAID0)
3768 sub_stripes = map->sub_stripes;
3770 factor = map->num_stripes / sub_stripes;
3771 stripes_per_dev = div_u64_rem(stripe_nr_end -
3774 &remaining_stripes);
3777 for (i = 0; i < num_stripes; i++) {
3778 bbio->stripes[i].physical =
3779 map->stripes[stripe_index].physical +
3780 stripe_offset + stripe_nr * map->stripe_len;
3781 bbio->stripes[i].dev = map->stripes[stripe_index].dev;
3783 if (map->type & (BTRFS_BLOCK_GROUP_RAID0 |
3784 BTRFS_BLOCK_GROUP_RAID10)) {
3785 bbio->stripes[i].length = stripes_per_dev *
3787 if (i / sub_stripes < remaining_stripes)
3788 bbio->stripes[i].length +=
3790 if (i < sub_stripes)
3791 bbio->stripes[i].length -=
3793 if ((i / sub_stripes + 1) %
3794 sub_stripes == remaining_stripes)
3795 bbio->stripes[i].length -=
3797 if (i == sub_stripes - 1)
3800 bbio->stripes[i].length = *length;
3803 if (stripe_index == map->num_stripes) {
3804 /* This could only happen for RAID0/10 */
3810 for (i = 0; i < num_stripes; i++) {
3811 bbio->stripes[i].physical =
3812 map->stripes[stripe_index].physical +
3814 stripe_nr * map->stripe_len;
3815 bbio->stripes[i].dev =
3816 map->stripes[stripe_index].dev;
3821 if (rw & REQ_WRITE) {
3822 if (map->type & (BTRFS_BLOCK_GROUP_RAID1 |
3823 BTRFS_BLOCK_GROUP_RAID10 |
3824 BTRFS_BLOCK_GROUP_DUP)) {
3830 bbio->num_stripes = num_stripes;
3831 bbio->max_errors = max_errors;
3832 bbio->mirror_num = mirror_num;
3834 free_extent_map(em);
3838 int btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
3839 u64 logical, u64 *length,
3840 struct btrfs_bio **bbio_ret, int mirror_num)
3842 return __btrfs_map_block(map_tree, rw, logical, length, bbio_ret,
3846 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
3847 u64 chunk_start, u64 physical, u64 devid,
3848 u64 **logical, int *naddrs, int *stripe_len)
3850 struct extent_map_tree *em_tree = &map_tree->map_tree;
3851 struct extent_map *em;
3852 struct map_lookup *map;
3859 read_lock(&em_tree->lock);
3860 em = lookup_extent_mapping(em_tree, chunk_start, 1);
3861 read_unlock(&em_tree->lock);
3863 BUG_ON(!em || em->start != chunk_start);
3864 map = (struct map_lookup *)em->bdev;
3867 if (map->type & BTRFS_BLOCK_GROUP_RAID10)
3868 do_div(length, map->num_stripes / map->sub_stripes);
3869 else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
3870 do_div(length, map->num_stripes);
3872 buf = kzalloc(sizeof(u64) * map->num_stripes, GFP_NOFS);
3875 for (i = 0; i < map->num_stripes; i++) {
3876 if (devid && map->stripes[i].dev->devid != devid)
3878 if (map->stripes[i].physical > physical ||
3879 map->stripes[i].physical + length <= physical)
3882 stripe_nr = physical - map->stripes[i].physical;
3883 do_div(stripe_nr, map->stripe_len);
3885 if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
3886 stripe_nr = stripe_nr * map->num_stripes + i;
3887 do_div(stripe_nr, map->sub_stripes);
3888 } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
3889 stripe_nr = stripe_nr * map->num_stripes + i;
3891 bytenr = chunk_start + stripe_nr * map->stripe_len;
3892 WARN_ON(nr >= map->num_stripes);
3893 for (j = 0; j < nr; j++) {
3894 if (buf[j] == bytenr)
3898 WARN_ON(nr >= map->num_stripes);
3905 *stripe_len = map->stripe_len;
3907 free_extent_map(em);
3911 static void btrfs_end_bio(struct bio *bio, int err)
3913 struct btrfs_bio *bbio = bio->bi_private;
3914 int is_orig_bio = 0;
3917 atomic_inc(&bbio->error);
3919 if (bio == bbio->orig_bio)
3922 if (atomic_dec_and_test(&bbio->stripes_pending)) {
3925 bio = bbio->orig_bio;
3927 bio->bi_private = bbio->private;
3928 bio->bi_end_io = bbio->end_io;
3929 bio->bi_bdev = (struct block_device *)
3930 (unsigned long)bbio->mirror_num;
3931 /* only send an error to the higher layers if it is
3932 * beyond the tolerance of the multi-bio
3934 if (atomic_read(&bbio->error) > bbio->max_errors) {
3938 * this bio is actually up to date, we didn't
3939 * go over the max number of errors
3941 set_bit(BIO_UPTODATE, &bio->bi_flags);
3946 bio_endio(bio, err);
3947 } else if (!is_orig_bio) {
3952 struct async_sched {
3955 struct btrfs_fs_info *info;
3956 struct btrfs_work work;
3960 * see run_scheduled_bios for a description of why bios are collected for
3963 * This will add one bio to the pending list for a device and make sure
3964 * the work struct is scheduled.
3966 static noinline int schedule_bio(struct btrfs_root *root,
3967 struct btrfs_device *device,
3968 int rw, struct bio *bio)
3970 int should_queue = 1;
3971 struct btrfs_pending_bios *pending_bios;
3973 /* don't bother with additional async steps for reads, right now */
3974 if (!(rw & REQ_WRITE)) {
3976 btrfsic_submit_bio(rw, bio);
3982 * nr_async_bios allows us to reliably return congestion to the
3983 * higher layers. Otherwise, the async bio makes it appear we have
3984 * made progress against dirty pages when we've really just put it
3985 * on a queue for later
3987 atomic_inc(&root->fs_info->nr_async_bios);
3988 WARN_ON(bio->bi_next);
3989 bio->bi_next = NULL;
3992 spin_lock(&device->io_lock);
3993 if (bio->bi_rw & REQ_SYNC)
3994 pending_bios = &device->pending_sync_bios;
3996 pending_bios = &device->pending_bios;
3998 if (pending_bios->tail)
3999 pending_bios->tail->bi_next = bio;
4001 pending_bios->tail = bio;
4002 if (!pending_bios->head)
4003 pending_bios->head = bio;
4004 if (device->running_pending)
4007 spin_unlock(&device->io_lock);
4010 btrfs_queue_worker(&root->fs_info->submit_workers,
4015 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
4016 int mirror_num, int async_submit)
4018 struct btrfs_mapping_tree *map_tree;
4019 struct btrfs_device *dev;
4020 struct bio *first_bio = bio;
4021 u64 logical = (u64)bio->bi_sector << 9;
4027 struct btrfs_bio *bbio = NULL;
4029 length = bio->bi_size;
4030 map_tree = &root->fs_info->mapping_tree;
4031 map_length = length;
4033 ret = btrfs_map_block(map_tree, rw, logical, &map_length, &bbio,
4037 total_devs = bbio->num_stripes;
4038 if (map_length < length) {
4039 printk(KERN_CRIT "mapping failed logical %llu bio len %llu "
4040 "len %llu\n", (unsigned long long)logical,
4041 (unsigned long long)length,
4042 (unsigned long long)map_length);
4046 bbio->orig_bio = first_bio;
4047 bbio->private = first_bio->bi_private;
4048 bbio->end_io = first_bio->bi_end_io;
4049 atomic_set(&bbio->stripes_pending, bbio->num_stripes);
4051 while (dev_nr < total_devs) {
4052 if (dev_nr < total_devs - 1) {
4053 bio = bio_clone(first_bio, GFP_NOFS);
4058 bio->bi_private = bbio;
4059 bio->bi_end_io = btrfs_end_bio;
4060 bio->bi_sector = bbio->stripes[dev_nr].physical >> 9;
4061 dev = bbio->stripes[dev_nr].dev;
4062 if (dev && dev->bdev && (rw != WRITE || dev->writeable)) {
4063 pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu "
4064 "(%s id %llu), size=%u\n", rw,
4065 (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev,
4066 dev->name, dev->devid, bio->bi_size);
4067 bio->bi_bdev = dev->bdev;
4069 schedule_bio(root, dev, rw, bio);
4071 btrfsic_submit_bio(rw, bio);
4073 bio->bi_bdev = root->fs_info->fs_devices->latest_bdev;
4074 bio->bi_sector = logical >> 9;
4075 bio_endio(bio, -EIO);
4082 struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
4085 struct btrfs_device *device;
4086 struct btrfs_fs_devices *cur_devices;
4088 cur_devices = root->fs_info->fs_devices;
4089 while (cur_devices) {
4091 !memcmp(cur_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
4092 device = __find_device(&cur_devices->devices,
4097 cur_devices = cur_devices->seed;
4102 static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
4103 u64 devid, u8 *dev_uuid)
4105 struct btrfs_device *device;
4106 struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
4108 device = kzalloc(sizeof(*device), GFP_NOFS);
4111 list_add(&device->dev_list,
4112 &fs_devices->devices);
4113 device->dev_root = root->fs_info->dev_root;
4114 device->devid = devid;
4115 device->work.func = pending_bios_fn;
4116 device->fs_devices = fs_devices;
4117 device->missing = 1;
4118 fs_devices->num_devices++;
4119 fs_devices->missing_devices++;
4120 spin_lock_init(&device->io_lock);
4121 INIT_LIST_HEAD(&device->dev_alloc_list);
4122 memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE);
4126 static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
4127 struct extent_buffer *leaf,
4128 struct btrfs_chunk *chunk)
4130 struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
4131 struct map_lookup *map;
4132 struct extent_map *em;
4136 u8 uuid[BTRFS_UUID_SIZE];
4141 logical = key->offset;
4142 length = btrfs_chunk_length(leaf, chunk);
4144 read_lock(&map_tree->map_tree.lock);
4145 em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
4146 read_unlock(&map_tree->map_tree.lock);
4148 /* already mapped? */
4149 if (em && em->start <= logical && em->start + em->len > logical) {
4150 free_extent_map(em);
4153 free_extent_map(em);
4156 em = alloc_extent_map();
4159 num_stripes = btrfs_chunk_num_stripes(leaf, chunk);
4160 map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
4162 free_extent_map(em);
4166 em->bdev = (struct block_device *)map;
4167 em->start = logical;
4169 em->block_start = 0;
4170 em->block_len = em->len;
4172 map->num_stripes = num_stripes;
4173 map->io_width = btrfs_chunk_io_width(leaf, chunk);
4174 map->io_align = btrfs_chunk_io_align(leaf, chunk);
4175 map->sector_size = btrfs_chunk_sector_size(leaf, chunk);
4176 map->stripe_len = btrfs_chunk_stripe_len(leaf, chunk);
4177 map->type = btrfs_chunk_type(leaf, chunk);
4178 map->sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk);
4179 for (i = 0; i < num_stripes; i++) {
4180 map->stripes[i].physical =
4181 btrfs_stripe_offset_nr(leaf, chunk, i);
4182 devid = btrfs_stripe_devid_nr(leaf, chunk, i);
4183 read_extent_buffer(leaf, uuid, (unsigned long)
4184 btrfs_stripe_dev_uuid_nr(chunk, i),
4186 map->stripes[i].dev = btrfs_find_device(root, devid, uuid,
4188 if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
4190 free_extent_map(em);
4193 if (!map->stripes[i].dev) {
4194 map->stripes[i].dev =
4195 add_missing_dev(root, devid, uuid);
4196 if (!map->stripes[i].dev) {
4198 free_extent_map(em);
4202 map->stripes[i].dev->in_fs_metadata = 1;
4205 write_lock(&map_tree->map_tree.lock);
4206 ret = add_extent_mapping(&map_tree->map_tree, em);
4207 write_unlock(&map_tree->map_tree.lock);
4209 free_extent_map(em);
4214 static int fill_device_from_item(struct extent_buffer *leaf,
4215 struct btrfs_dev_item *dev_item,
4216 struct btrfs_device *device)
4220 device->devid = btrfs_device_id(leaf, dev_item);
4221 device->disk_total_bytes = btrfs_device_total_bytes(leaf, dev_item);
4222 device->total_bytes = device->disk_total_bytes;
4223 device->bytes_used = btrfs_device_bytes_used(leaf, dev_item);
4224 device->type = btrfs_device_type(leaf, dev_item);
4225 device->io_align = btrfs_device_io_align(leaf, dev_item);
4226 device->io_width = btrfs_device_io_width(leaf, dev_item);
4227 device->sector_size = btrfs_device_sector_size(leaf, dev_item);
4229 ptr = (unsigned long)btrfs_device_uuid(dev_item);
4230 read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
4235 static int open_seed_devices(struct btrfs_root *root, u8 *fsid)
4237 struct btrfs_fs_devices *fs_devices;
4240 BUG_ON(!mutex_is_locked(&uuid_mutex));
4242 fs_devices = root->fs_info->fs_devices->seed;
4243 while (fs_devices) {
4244 if (!memcmp(fs_devices->fsid, fsid, BTRFS_UUID_SIZE)) {
4248 fs_devices = fs_devices->seed;
4251 fs_devices = find_fsid(fsid);
4257 fs_devices = clone_fs_devices(fs_devices);
4258 if (IS_ERR(fs_devices)) {
4259 ret = PTR_ERR(fs_devices);
4263 ret = __btrfs_open_devices(fs_devices, FMODE_READ,
4264 root->fs_info->bdev_holder);
4268 if (!fs_devices->seeding) {
4269 __btrfs_close_devices(fs_devices);
4270 free_fs_devices(fs_devices);
4275 fs_devices->seed = root->fs_info->fs_devices->seed;
4276 root->fs_info->fs_devices->seed = fs_devices;
4281 static int read_one_dev(struct btrfs_root *root,
4282 struct extent_buffer *leaf,
4283 struct btrfs_dev_item *dev_item)
4285 struct btrfs_device *device;
4288 u8 fs_uuid[BTRFS_UUID_SIZE];
4289 u8 dev_uuid[BTRFS_UUID_SIZE];
4291 devid = btrfs_device_id(leaf, dev_item);
4292 read_extent_buffer(leaf, dev_uuid,
4293 (unsigned long)btrfs_device_uuid(dev_item),
4295 read_extent_buffer(leaf, fs_uuid,
4296 (unsigned long)btrfs_device_fsid(dev_item),
4299 if (memcmp(fs_uuid, root->fs_info->fsid, BTRFS_UUID_SIZE)) {
4300 ret = open_seed_devices(root, fs_uuid);
4301 if (ret && !btrfs_test_opt(root, DEGRADED))
4305 device = btrfs_find_device(root, devid, dev_uuid, fs_uuid);
4306 if (!device || !device->bdev) {
4307 if (!btrfs_test_opt(root, DEGRADED))
4311 printk(KERN_WARNING "warning devid %llu missing\n",
4312 (unsigned long long)devid);
4313 device = add_missing_dev(root, devid, dev_uuid);
4316 } else if (!device->missing) {
4318 * this happens when a device that was properly setup
4319 * in the device info lists suddenly goes bad.
4320 * device->bdev is NULL, and so we have to set
4321 * device->missing to one here
4323 root->fs_info->fs_devices->missing_devices++;
4324 device->missing = 1;
4328 if (device->fs_devices != root->fs_info->fs_devices) {
4329 BUG_ON(device->writeable);
4330 if (device->generation !=
4331 btrfs_device_generation(leaf, dev_item))
4335 fill_device_from_item(leaf, dev_item, device);
4336 device->dev_root = root->fs_info->dev_root;
4337 device->in_fs_metadata = 1;
4338 if (device->writeable) {
4339 device->fs_devices->total_rw_bytes += device->total_bytes;
4340 spin_lock(&root->fs_info->free_chunk_lock);
4341 root->fs_info->free_chunk_space += device->total_bytes -
4343 spin_unlock(&root->fs_info->free_chunk_lock);
4349 int btrfs_read_sys_array(struct btrfs_root *root)
4351 struct btrfs_super_block *super_copy = root->fs_info->super_copy;
4352 struct extent_buffer *sb;
4353 struct btrfs_disk_key *disk_key;
4354 struct btrfs_chunk *chunk;
4356 unsigned long sb_ptr;
4362 struct btrfs_key key;
4364 sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
4365 BTRFS_SUPER_INFO_SIZE);
4368 btrfs_set_buffer_uptodate(sb);
4369 btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0);
4371 * The sb extent buffer is artifical and just used to read the system array.
4372 * btrfs_set_buffer_uptodate() call does not properly mark all it's
4373 * pages up-to-date when the page is larger: extent does not cover the
4374 * whole page and consequently check_page_uptodate does not find all
4375 * the page's extents up-to-date (the hole beyond sb),
4376 * write_extent_buffer then triggers a WARN_ON.
4378 * Regular short extents go through mark_extent_buffer_dirty/writeback cycle,
4379 * but sb spans only this function. Add an explicit SetPageUptodate call
4380 * to silence the warning eg. on PowerPC 64.
4382 if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE)
4383 SetPageUptodate(sb->pages[0]);
4385 write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
4386 array_size = btrfs_super_sys_array_size(super_copy);
4388 ptr = super_copy->sys_chunk_array;
4389 sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
4392 while (cur < array_size) {
4393 disk_key = (struct btrfs_disk_key *)ptr;
4394 btrfs_disk_key_to_cpu(&key, disk_key);
4396 len = sizeof(*disk_key); ptr += len;
4400 if (key.type == BTRFS_CHUNK_ITEM_KEY) {
4401 chunk = (struct btrfs_chunk *)sb_ptr;
4402 ret = read_one_chunk(root, &key, sb, chunk);
4405 num_stripes = btrfs_chunk_num_stripes(sb, chunk);
4406 len = btrfs_chunk_item_size(num_stripes);
4415 free_extent_buffer(sb);
4419 int btrfs_read_chunk_tree(struct btrfs_root *root)
4421 struct btrfs_path *path;
4422 struct extent_buffer *leaf;
4423 struct btrfs_key key;
4424 struct btrfs_key found_key;
4428 root = root->fs_info->chunk_root;
4430 path = btrfs_alloc_path();
4434 mutex_lock(&uuid_mutex);
4437 /* first we search for all of the device items, and then we
4438 * read in all of the chunk items. This way we can create chunk
4439 * mappings that reference all of the devices that are afound
4441 key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
4445 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
4449 leaf = path->nodes[0];
4450 slot = path->slots[0];
4451 if (slot >= btrfs_header_nritems(leaf)) {
4452 ret = btrfs_next_leaf(root, path);
4459 btrfs_item_key_to_cpu(leaf, &found_key, slot);
4460 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
4461 if (found_key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
4463 if (found_key.type == BTRFS_DEV_ITEM_KEY) {
4464 struct btrfs_dev_item *dev_item;
4465 dev_item = btrfs_item_ptr(leaf, slot,
4466 struct btrfs_dev_item);
4467 ret = read_one_dev(root, leaf, dev_item);
4471 } else if (found_key.type == BTRFS_CHUNK_ITEM_KEY) {
4472 struct btrfs_chunk *chunk;
4473 chunk = btrfs_item_ptr(leaf, slot, struct btrfs_chunk);
4474 ret = read_one_chunk(root, &found_key, leaf, chunk);
4480 if (key.objectid == BTRFS_DEV_ITEMS_OBJECTID) {
4482 btrfs_release_path(path);
4487 unlock_chunks(root);
4488 mutex_unlock(&uuid_mutex);
4490 btrfs_free_path(path);