Btrfs: make defragment work with nodatacow option
Btrfs defragment will utilize COW feature, which means this
did not work for nodatacow option, this problem was detected
by xfstests generic/018 with nodatacow mount option.
Fix this problem by forcing cow for a extent with state
@EXTETN_DEFRAG setting.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index 43527fd..fd87941 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -121,6 +121,12 @@
u64 delalloc_bytes;
/*
+ * total number of bytes pending defrag, used by stat to check whether
+ * it needs COW.
+ */
+ u64 defrag_bytes;
+
+ /*
* the size of the file stored in the metadata on disk. data=ordered
* means the in-memory i_size might be larger than the size on disk
* because not all the blocks are written yet.