Btrfs: check duplicate backrefs for both data and metadata

lookup_inline_extent_backref only checks for duplicate backref for data
extents. It assumes backrefs for tree block never conflict.

This patch makes lookup_inline_extent_backref check for duplicate backrefs
for both data and tree block, so that we can detect potential bug earlier.
This is a safety check, strictly speaking it is not required.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Yan Zheng 2009-06-11 08:51:10 -04:00 committed by Chris Mason
parent fd0fb038d5
commit 85d4198e40

View File

@ -1056,8 +1056,7 @@ int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
want = extent_ref_type(parent, owner);
if (insert) {
extra_size = btrfs_extent_inline_ref_size(want);
if (owner >= BTRFS_FIRST_FREE_OBJECTID)
path->keep_locks = 1;
path->keep_locks = 1;
} else
extra_size = -1;
ret = btrfs_search_slot(trans, root, &key, path, extra_size, 1);
@ -1087,12 +1086,6 @@ int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
#endif
BUG_ON(item_size < sizeof(*ei));
if (owner < BTRFS_FIRST_FREE_OBJECTID && insert &&
item_size + extra_size >= BTRFS_MAX_EXTENT_ITEM_SIZE(root)) {
err = -EAGAIN;
goto out;
}
ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_item);
flags = btrfs_extent_flags(leaf, ei);
@ -1165,15 +1158,15 @@ int lookup_inline_extent_backref(struct btrfs_trans_handle *trans,
* For simplicity, we just do not add new inline back
* ref if there is any kind of item for this block
*/
if (owner >= BTRFS_FIRST_FREE_OBJECTID &&
find_next_key(path, &key) == 0 && key.objectid == bytenr) {
if (find_next_key(path, &key) == 0 && key.objectid == bytenr &&
key.type < BTRFS_BLOCK_GROUP_ITEM_KEY) {
err = -EAGAIN;
goto out;
}
}
*ref_ret = (struct btrfs_extent_inline_ref *)ptr;
out:
if (insert && owner >= BTRFS_FIRST_FREE_OBJECTID) {
if (insert) {
path->keep_locks = 0;
btrfs_unlock_up_safe(path, 1);
}