Btrfs: use flag EXTENT_DEFRAG for snapshot-aware defrag
We're going to use this flag EXTENT_DEFRAG to indicate which range
belongs to defragment so that we can implement snapshow-aware defrag:
We set the EXTENT_DEFRAG flag when dirtying the extents that need
defragmented, so later on writeback thread can differentiate between
normal writeback and writeback started by defragmentation.
Original-Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index c56daa3..de886ac 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1023,8 +1023,8 @@
page_start, page_end - 1, 0, &cached_state);
clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
- EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
- GFP_NOFS);
+ EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
+ &cached_state, GFP_NOFS);
if (i_done != page_cnt) {
spin_lock(&BTRFS_I(inode)->lock);
@@ -1035,8 +1035,8 @@
}
- btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
- &cached_state);
+ set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
+ &cached_state, GFP_NOFS);
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
page_start, page_end - 1, &cached_state,