Btrfs: record first logical byte in memory
This'd save us a rbtree search which may become expensive in large filesystem.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 1db8a99..04f98e3 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2130,6 +2130,7 @@
spin_lock_init(&fs_info->block_group_cache_lock);
fs_info->block_group_cache_tree = RB_ROOT;
+ fs_info->first_logical_byte = (u64)-1;
extent_io_tree_init(&fs_info->freed_extents[0],
fs_info->btree_inode->i_mapping);