Btrfs: Add BH_Defrag to mark buffers that are in need of defragging

This allows the tree walking code to defrag only the newly allocated
buffers, it seems to be a good balance between perfect defragging and the
performance hit of repeatedly reallocating blocks.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index 9e2c261b41ae..81fd18cbd824 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -25,8 +25,10 @@
 
 enum btrfs_bh_state_bits {
         BH_Checked = BH_PrivateStart,
+        BH_Defrag,
 };
 BUFFER_FNS(Checked, checked);
+BUFFER_FNS(Defrag, defrag);
 
 static inline struct btrfs_node *btrfs_buffer_node(struct buffer_head *bh)
 {