diff options
Diffstat (limited to 'fs/btrfs/extent-tree.c')
-rw-r--r-- | fs/btrfs/extent-tree.c | 45 |
1 files changed, 41 insertions, 4 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 5ace2c33f1aa..9455974dabea 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -1561,12 +1561,21 @@ static int walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root int i; int slot; int ret; + struct btrfs_root_item *root_item = &root->root_item; + for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) { slot = path->slots[i]; if (slot < btrfs_header_nritems( btrfs_buffer_header(path->nodes[i])) - 1) { + struct btrfs_node *node; + node = btrfs_buffer_node(path->nodes[i]); path->slots[i]++; *level = i; + WARN_ON(*level == 0); + memcpy(&root_item->drop_progress, + &node->ptrs[path->slots[i]].key, + sizeof(root_item->drop_progress)); + root_item->drop_level = i; return 0; } else { ret = btrfs_free_extent(trans, root, @@ -1587,7 +1596,7 @@ static int walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root * decremented. */ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root - *root, struct buffer_head *snap) + *root) { int ret = 0; int wret; @@ -1595,14 +1604,33 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root struct btrfs_path *path; int i; int orig_level; + int num_walks = 0; + struct btrfs_root_item *root_item = &root->root_item; path = btrfs_alloc_path(); BUG_ON(!path); - level = btrfs_header_level(btrfs_buffer_header(snap)); + level = btrfs_header_level(btrfs_buffer_header(root->node)); orig_level = level; - path->nodes[level] = snap; - path->slots[level] = 0; + if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { + path->nodes[level] = root->node; + path->slots[level] = 0; + } else { + struct btrfs_key key; + struct btrfs_disk_key *found_key; + struct btrfs_node *node; + btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); + wret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) { + ret = wret; + goto out; + } + level = root_item->drop_level; + node = btrfs_buffer_node(path->nodes[level]); + found_key = &node->ptrs[path->slots[level]].key; + WARN_ON(memcmp(found_key, &root_item->drop_progress, + sizeof(*found_key))); + } while(1) { wret = walk_down_tree(trans, root, path, &level); if (wret > 0) @@ -1615,12 +1643,21 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root break; if (wret < 0) ret = wret; + num_walks++; + if (num_walks > 10) { + struct btrfs_key key; + btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); + ret = -EAGAIN; + get_bh(root->node); + break; + } } for (i = 0; i <= orig_level; i++) { if (path->nodes[i]) { btrfs_block_release(root, path->nodes[i]); } } +out: btrfs_free_path(path); return ret; } |