diff options
authorLiu Bo <bo.li.liu@oracle.com>2013-03-15 08:46:39 -0600
committerChris Mason <chris.mason@fusionio.com>2013-03-15 21:51:49 -0400
commit3b2775942d6ccb14342f3aae55f22fbbfea8db14 (patch)
parent7c2ec3f0730729f4829d01f7c19538d135f86712 (diff)
Btrfs: fix warning of free_extent_map
Users report that an extent map's list is still linked when it's actually going to be freed from cache. The story is that a) when we're going to drop an extent map and may split this large one into smaller ems, and if this large one is flagged as EXTENT_FLAG_LOGGING which means that it's on the list to be logged, then the smaller ems split from it will also be flagged as EXTENT_FLAG_LOGGING, and this is _not_ expected. b) we'll keep ems from unlinking the list and freeing when they are flagged with EXTENT_FLAG_LOGGING, because the log code holds one reference. The end result is the warning, but the truth is that we set the flag EXTENT_FLAG_LOGGING only during fsync. So clear flag EXTENT_FLAG_LOGGING for extent maps split from a large one. Reported-by: Johannes Hirte <johannes.hirte@fem.tu-ilmenau.de> Reported-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 83c790d84038..7bdb47faa12e 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -591,6 +591,7 @@ void btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
clear_bit(EXTENT_FLAG_PINNED, &em->flags);
+ clear_bit(EXTENT_FLAG_LOGGING, &flags);
remove_extent_mapping(em_tree, em);
if (no_splits)
goto next;