struct btrfs_caching_control *ctl;
spin_lock(&cache->lock);
- if (cache->cached != BTRFS_CACHE_STARTED) {
- spin_unlock(&cache->lock);
- return NULL;
- }
-
- /* We're loading it the fast way, so we don't have a caching_ctl. */
if (!cache->caching_ctl) {
spin_unlock(&cache->lock);
return NULL;
spin_unlock(&cache->lock);
if (fs_info->mount_opt & BTRFS_MOUNT_SPACE_CACHE) {
+ mutex_lock(&caching_ctl->mutex);
ret = load_free_space_cache(fs_info, cache);
spin_lock(&cache->lock);
cache->caching_ctl = NULL;
cache->cached = BTRFS_CACHE_FINISHED;
cache->last_byte_to_unpin = (u64)-1;
+ caching_ctl->progress = (u64)-1;
} else {
if (load_cache_only) {
cache->caching_ctl = NULL;
cache->cached = BTRFS_CACHE_NO;
} else {
cache->cached = BTRFS_CACHE_STARTED;
+ cache->has_caching_ctl = 1;
}
}
spin_unlock(&cache->lock);
+ mutex_unlock(&caching_ctl->mutex);
+
wake_up(&caching_ctl->wait);
if (ret == 1) {
put_caching_control(caching_ctl);
cache->cached = BTRFS_CACHE_NO;
} else {
cache->cached = BTRFS_CACHE_STARTED;
+ cache->has_caching_ctl = 1;
}
spin_unlock(&cache->lock);
wake_up(&caching_ctl->wait);
struct btrfs_block_group_cache *cache)
{
struct rb_node *node;
+
spin_lock(&root->fs_info->block_group_cache_lock);
+
+ /* If our block group was removed, we need a full search. */
+ if (RB_EMPTY_NODE(&cache->cache_node)) {
+ const u64 next_bytenr = cache->key.objectid + cache->key.offset;
+
+ spin_unlock(&root->fs_info->block_group_cache_lock);
+ btrfs_put_block_group(cache);
+ cache = btrfs_lookup_first_block_group(root->fs_info,
+ next_bytenr);
+ return cache;
+ }
node = rb_next(&cache->cache_node);
btrfs_put_block_group(cache);
if (node) {
found->chunk_alloc = 0;
found->flush = 0;
init_waitqueue_head(&found->wait);
+ INIT_LIST_HEAD(&found->ro_bgs);
ret = kobject_init_and_add(&found->kobj, &space_info_ktype,
info->space_info_kobj, "%s",
spin_unlock(&cache->space_info->lock);
} else {
old_val -= num_bytes;
+ btrfs_set_block_group_used(&cache->item, old_val);
+ cache->pinned += num_bytes;
+ cache->space_info->bytes_pinned += num_bytes;
+ cache->space_info->bytes_used -= num_bytes;
+ cache->space_info->disk_used -= num_bytes * factor;
+ spin_unlock(&cache->lock);
+ spin_unlock(&cache->space_info->lock);
+ set_extent_dirty(info->pinned_extents,
+ bytenr, bytenr + num_bytes - 1,
+ GFP_NOFS | __GFP_NOFAIL);
/*
* No longer have used bytes in this block group, queue
* it for deletion.
}
spin_unlock(&info->unused_bgs_lock);
}
- btrfs_set_block_group_used(&cache->item, old_val);
- cache->pinned += num_bytes;
- cache->space_info->bytes_pinned += num_bytes;
- cache->space_info->bytes_used -= num_bytes;
- cache->space_info->disk_used -= num_bytes * factor;
- spin_unlock(&cache->lock);
- spin_unlock(&cache->space_info->lock);
-
- set_extent_dirty(info->pinned_extents,
- bytenr, bytenr + num_bytes - 1,
- GFP_NOFS | __GFP_NOFAIL);
}
btrfs_put_block_group(cache);
total -= num_bytes;
min_allocable_bytes <= sinfo->total_bytes) {
sinfo->bytes_readonly += num_bytes;
cache->ro = 1;
+ list_add_tail(&cache->ro_list, &sinfo->ro_bgs);
ret = 0;
}
out:
/*
* helper to account the unused space of all the readonly block group in the
- * list. takes mirrors into account.
+ * space_info. takes mirrors into account.
*/
-static u64 __btrfs_get_ro_block_group_free_space(struct list_head *groups_list)
+u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
{
struct btrfs_block_group_cache *block_group;
u64 free_bytes = 0;
int factor;
- list_for_each_entry(block_group, groups_list, list) {
+ /* It's df, we don't care if it's racey */
+ if (list_empty(&sinfo->ro_bgs))
+ return 0;
+
+ spin_lock(&sinfo->lock);
+ list_for_each_entry(block_group, &sinfo->ro_bgs, ro_list) {
spin_lock(&block_group->lock);
if (!block_group->ro) {
spin_unlock(&block_group->lock);
}
-
- return free_bytes;
-}
-
-/*
- * helper to account the unused space of all the readonly block group in the
- * space_info. takes mirrors into account.
- */
-u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo)
-{
- int i;
- u64 free_bytes = 0;
-
- spin_lock(&sinfo->lock);
-
- for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
- if (!list_empty(&sinfo->block_groups[i]))
- free_bytes += __btrfs_get_ro_block_group_free_space(
- &sinfo->block_groups[i]);
-
spin_unlock(&sinfo->lock);
return free_bytes;
cache->bytes_super - btrfs_block_group_used(&cache->item);
sinfo->bytes_readonly -= num_bytes;
cache->ro = 0;
+ list_del_init(&cache->ro_list);
spin_unlock(&cache->lock);
spin_unlock(&sinfo->lock);
}
INIT_LIST_HEAD(&cache->list);
INIT_LIST_HEAD(&cache->cluster_list);
INIT_LIST_HEAD(&cache->bg_list);
+ INIT_LIST_HEAD(&cache->ro_list);
btrfs_init_free_space_ctl(cache);
+ atomic_set(&cache->trimming, 0);
return cache;
}
int ret = 0;
list_for_each_entry_safe(block_group, tmp, &trans->new_bgs, bg_list) {
- list_del_init(&block_group->bg_list);
if (ret)
- continue;
+ goto next;
spin_lock(&block_group->lock);
memcpy(&item, &block_group->item, sizeof(item));
key.objectid, key.offset);
if (ret)
btrfs_abort_transaction(trans, extent_root, ret);
+next:
+ list_del_init(&block_group->bg_list);
}
}
}
int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 group_start)
+ struct btrfs_root *root, u64 group_start,
+ struct extent_map *em)
{
struct btrfs_path *path;
struct btrfs_block_group_cache *block_group;
int ret;
int index;
int factor;
+ struct btrfs_caching_control *caching_ctl = NULL;
+ bool remove_em;
root = root->fs_info->extent_root;
spin_lock(&root->fs_info->block_group_cache_lock);
rb_erase(&block_group->cache_node,
&root->fs_info->block_group_cache_tree);
+ RB_CLEAR_NODE(&block_group->cache_node);
if (root->fs_info->first_logical_byte == block_group->key.objectid)
root->fs_info->first_logical_byte = (u64)-1;
* are still on the list after taking the semaphore
*/
list_del_init(&block_group->list);
+ list_del_init(&block_group->ro_list);
if (list_empty(&block_group->space_info->block_groups[index])) {
kobj = block_group->space_info->block_group_kobjs[index];
block_group->space_info->block_group_kobjs[index] = NULL;
kobject_put(kobj);
}
+ if (block_group->has_caching_ctl)
+ caching_ctl = get_caching_control(block_group);
if (block_group->cached == BTRFS_CACHE_STARTED)
wait_block_group_cache_done(block_group);
+ if (block_group->has_caching_ctl) {
+ down_write(&root->fs_info->commit_root_sem);
+ if (!caching_ctl) {
+ struct btrfs_caching_control *ctl;
+
+ list_for_each_entry(ctl,
+ &root->fs_info->caching_block_groups, list)
+ if (ctl->block_group == block_group) {
+ caching_ctl = ctl;
+ atomic_inc(&caching_ctl->count);
+ break;
+ }
+ }
+ if (caching_ctl)
+ list_del_init(&caching_ctl->list);
+ up_write(&root->fs_info->commit_root_sem);
+ if (caching_ctl) {
+ /* Once for the caching bgs list and once for us. */
+ put_caching_control(caching_ctl);
+ put_caching_control(caching_ctl);
+ }
+ }
btrfs_remove_free_space_cache(block_group);
memcpy(&key, &block_group->key, sizeof(key));
+ lock_chunks(root);
+ if (!list_empty(&em->list)) {
+ /* We're in the transaction->pending_chunks list. */
+ free_extent_map(em);
+ }
+ spin_lock(&block_group->lock);
+ block_group->removed = 1;
+ /*
+ * At this point trimming can't start on this block group, because we
+ * removed the block group from the tree fs_info->block_group_cache_tree
+ * so no one can't find it anymore and even if someone already got this
+ * block group before we removed it from the rbtree, they have already
+ * incremented block_group->trimming - if they didn't, they won't find
+ * any free space entries because we already removed them all when we
+ * called btrfs_remove_free_space_cache().
+ *
+ * And we must not remove the extent map from the fs_info->mapping_tree
+ * to prevent the same logical address range and physical device space
+ * ranges from being reused for a new block group. This is because our
+ * fs trim operation (btrfs_trim_fs() / btrfs_ioctl_fitrim()) is
+ * completely transactionless, so while it is trimming a range the
+ * currently running transaction might finish and a new one start,
+ * allowing for new block groups to be created that can reuse the same
+ * physical device locations unless we take this special care.
+ */
+ remove_em = (atomic_read(&block_group->trimming) == 0);
+ /*
+ * Make sure a trimmer task always sees the em in the pinned_chunks list
+ * if it sees block_group->removed == 1 (needs to lock block_group->lock
+ * before checking block_group->removed).
+ */
+ if (!remove_em) {
+ /*
+ * Our em might be in trans->transaction->pending_chunks which
+ * is protected by fs_info->chunk_mutex ([lock|unlock]_chunks),
+ * and so is the fs_info->pinned_chunks list.
+ *
+ * So at this point we must be holding the chunk_mutex to avoid
+ * any races with chunk allocation (more specifically at
+ * volumes.c:contains_pending_extent()), to ensure it always
+ * sees the em, either in the pending_chunks list or in the
+ * pinned_chunks list.
+ */
+ list_move_tail(&em->list, &root->fs_info->pinned_chunks);
+ }
+ spin_unlock(&block_group->lock);
+
+ if (remove_em) {
+ struct extent_map_tree *em_tree;
+
+ em_tree = &root->fs_info->mapping_tree.map_tree;
+ write_lock(&em_tree->lock);
+ /*
+ * The em might be in the pending_chunks list, so make sure the
+ * chunk mutex is locked, since remove_extent_mapping() will
+ * delete us from that list.
+ */
+ remove_extent_mapping(em_tree, em);
+ write_unlock(&em_tree->lock);
+ /* once for the tree */
+ free_extent_map(em);
+ }
+
+ unlock_chunks(root);
+
btrfs_put_block_group(block_group);
btrfs_put_block_group(block_group);
*/
start = block_group->key.objectid;
end = start + block_group->key.offset - 1;
- clear_extent_bits(&fs_info->freed_extents[0], start, end,
+ ret = clear_extent_bits(&fs_info->freed_extents[0], start, end,
EXTENT_DIRTY, GFP_NOFS);
- clear_extent_bits(&fs_info->freed_extents[1], start, end,
+ if (ret) {
+ btrfs_set_block_group_rw(root, block_group);
+ goto end_trans;
+ }
+ ret = clear_extent_bits(&fs_info->freed_extents[1], start, end,
EXTENT_DIRTY, GFP_NOFS);
+ if (ret) {
+ btrfs_set_block_group_rw(root, block_group);
+ goto end_trans;
+ }
/* Reset pinned so btrfs_put_block_group doesn't complain */
block_group->pinned = 0;
*/
ret = btrfs_remove_chunk(trans, root,
block_group->key.objectid);
+end_trans:
btrfs_end_transaction(trans, root);
next:
btrfs_put_block_group(block_group);
}
/*
- * btrfs_{start,end}_write() is similar to mnt_{want, drop}_write(),
- * they are used to prevent the some tasks writing data into the page cache
- * by nocow before the subvolume is snapshoted, but flush the data into
- * the disk after the snapshot creation.
+ * btrfs_{start,end}_write_no_snapshoting() are similar to
+ * mnt_{want,drop}_write(), they are used to prevent some tasks from writing
+ * data into the page cache through nocow before the subvolume is snapshoted,
+ * but flush the data into disk after the snapshot creation, or to prevent
+ * operations while snapshoting is ongoing and that cause the snapshot to be
+ * inconsistent (writes followed by expanding truncates for example).
*/
-void btrfs_end_nocow_write(struct btrfs_root *root)
+void btrfs_end_write_no_snapshoting(struct btrfs_root *root)
{
percpu_counter_dec(&root->subv_writers->counter);
/*
wake_up(&root->subv_writers->wait);
}
-int btrfs_start_nocow_write(struct btrfs_root *root)
+int btrfs_start_write_no_snapshoting(struct btrfs_root *root)
{
if (atomic_read(&root->will_be_snapshoted))
return 0;
*/
smp_mb();
if (atomic_read(&root->will_be_snapshoted)) {
- btrfs_end_nocow_write(root);
+ btrfs_end_write_no_snapshoting(root);
return 0;
}
return 1;
projects / cascardo / linux.git / blobdiff