| Message ID | 1350640255-3760-1-git-send-email-bo.li.liu@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index b334362..2858c2f 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1142,13 +1142,13 @@ __tree_mod_log_rewind(struct extent_buffer *eb, u64 time_seq, switch (tm->op) { case MOD_LOG_KEY_REMOVE_WHILE_FREEING: BUG_ON(tm->slot < n); - case MOD_LOG_KEY_REMOVE_WHILE_MOVING: case MOD_LOG_KEY_REMOVE: + n++; + case MOD_LOG_KEY_REMOVE_WHILE_MOVING: btrfs_set_node_key(eb, &tm->key, tm->slot); btrfs_set_node_blockptr(eb, tm->slot, tm->blockptr); btrfs_set_node_ptr_generation(eb, tm->slot, tm->generation); - n++; break; case MOD_LOG_KEY_REPLACE: BUG_ON(tm->slot >= n);
Key MOD_LOG_KEY_REMOVE_WHILE_MOVING means that we're doing memmove inside an extent buffer node, and the node's number of items remains unchanged (unless we are inserting a single pointer, but we have MOD_LOG_KEY_ADD for that). So we don't need to increase node's number of items during rewinding, otherwise we may get an node larger than leafsize and cause general protection errors later. Here is the details, - If we do memory move for inserting a single pointer, we need to add node's nritems by one, and we honor MOD_LOG_KEY_ADD for adding. - If we do memory move for deleting a single pointer, we need to decrease node's nritems by one, and we honor MOD_LOG_KEY_REMOVE for deleting. - If we do memory move for balance left/right, we need to decrease node's nritems, and we honor MOD_LOG_KEY_REMOVE for balaning. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> --- fs/btrfs/ctree.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-)