Btrfs: introduce per-subvolume ordered extent list

The reason we introduce per-subvolume ordered extent list is the same
as the per-subvolume delalloc inode list.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

1 files changed, 20 insertions, 5 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 43c073533940..905f7c6c82f3 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1437,17 +1437,18 @@ struct btrfs_fs_info {
         atomic_t open_ioctl_trans;
 
         /*
-         * this is used by the balancing code to wait for all the pending
-         * ordered extents
+         * this is used to protect the following list -- ordered_roots.
          */
-        spinlock_t ordered_extent_lock;
+        spinlock_t ordered_root_lock;
 
         /*
-         * all of the data=ordered extents pending writeback
+         * all fs/file tree roots in which there are data=ordered extents
+         * pending writeback are added into this list.
+         *
          * these can span multiple transactions and basically include
          * every dirty data page that isn't from nodatacow
          */
-        struct list_head ordered_extents;
+        struct list_head ordered_roots;
 
         spinlock_t delalloc_root_lock;
         /* all fs/file tree roots that have delalloc inodes. */
@@ -1753,6 +1754,20 @@ struct btrfs_root {
         struct list_head delalloc_inodes;
         struct list_head delalloc_root;
         u64 nr_delalloc_inodes;
+        /*
+         * this is used by the balancing code to wait for all the pending
+         * ordered extents
+         */
+        spinlock_t ordered_extent_lock;
+
+        /*
+         * all of the data=ordered extents pending writeback
+         * these can span multiple transactions and basically include
+         * every dirty data page that isn't from nodatacow
+         */
+        struct list_head ordered_extents;
+        struct list_head ordered_root;
+        u64 nr_ordered_extents;
 };
 
 struct btrfs_ioctl_defrag_range_args {