From 95c80bb1f6b24b57058d971ed252b2c1c5121b51 Mon Sep 17 00:00:00 2001 From: Liu Bo Date: Fri, 19 Oct 2012 09:50:52 +0000 Subject: [PATCH] Btrfs: MOD_LOG_KEY_REMOVE_WHILE_MOVING never change node's nritems 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 Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index cdfb4c49a80..b12c0395916 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1140,13 +1140,13 @@ __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);