Btrfs: comment for loop in tree_mod_log_insert_move

Emphasis the way tree_mod_log_insert_move avoids adding
MOD_LOG_KEY_REMOVE_WHILE_MOVING operations, depending on the direction of
the move operation.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
This commit is contained in:
Jan Schmidt 2012-10-23 15:02:12 +02:00
parent d638108484
commit 01763a2e37

View File

@ -596,6 +596,11 @@ tree_mod_log_insert_move(struct btrfs_fs_info *fs_info,
if (tree_mod_dont_log(fs_info, eb))
return 0;
/*
* When we override something during the move, we log these removals.
* This can only happen when we move towards the beginning of the
* buffer, i.e. dst_slot < src_slot.
*/
for (i = 0; i + dst_slot < src_slot && i < nr_items; i++) {
ret = tree_mod_log_insert_key_locked(fs_info, eb, i + dst_slot,
MOD_LOG_KEY_REMOVE_WHILE_MOVING);