btrfs-progs: switch dev stats item to the permanent item key

[ kernel patch 242e2956e4afde7727fffe21adc0a7b198b77f96 ]
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/ctree.h b/ctree.h
index 255ebad..eb6e36b 100644 (file)
--- a/ctree.h
+++ b/ctree.h
@@ -85,6 +85,9 @@ struct btrfs_free_space_ctl;
 /* tracks free space in block groups. */
 #define BTRFS_FREE_SPACE_TREE_OBJECTID 10ULL
 
+/* device stats in the device tree */
+#define BTRFS_DEV_STATS_OBJECTID 0ULL
+
 /* for storing balance parameters in the root tree */
 #define BTRFS_BALANCE_OBJECTID -4ULL
 
@@ -1244,7 +1247,7 @@ struct btrfs_root {
  *
  * - device statistics, store IO stats in the device tree, one key for all
  *   stats
- *   (0, BTRFS_DEV_STATS_KEY, 0)
+ *   (BTRFS_DEV_STATS_OBJECTID, BTRFS_DEV_STATS_KEY, 0)
  */
 #define BTRFS_PERSISTENT_ITEM_KEY      249