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authorDavid Sterba <dsterba@suse.com>2016-02-26 14:38:29 (GMT)
committerDavid Sterba <dsterba@suse.com>2016-02-26 14:38:29 (GMT)
commit67d605fec1d406f6a0272be39686801d389f59c9 (patch)
tree4b8e7a25138db7369f5a6e0882d591984861d303 /fs/btrfs/ctree.h
parente22b3d1fbe596c7feba6782dab2e11c7b99f1d90 (diff)
parent9f07e1d76eaeeddedcf9651395b4a8f870df31f0 (diff)
downloadlinux-67d605fec1d406f6a0272be39686801d389f59c9.tar.xz
Merge branch 'dev/rename-keys' into for-chris-4.6
Diffstat (limited to 'fs/btrfs/ctree.h')
-rw-r--r--fs/btrfs/ctree.h39
1 files changed, 36 insertions, 3 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 5f5c4fb..3fb3b78 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -100,6 +100,9 @@ struct btrfs_ordered_sum;
/* 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
@@ -2185,13 +2188,43 @@ struct btrfs_ioctl_defrag_range_args {
*/
#define BTRFS_QGROUP_RELATION_KEY 246
+/*
+ * Obsolete name, see BTRFS_TEMPORARY_ITEM_KEY.
+ */
#define BTRFS_BALANCE_ITEM_KEY 248
/*
- * Persistantly stores the io stats in the device tree.
- * One key for all stats, (0, BTRFS_DEV_STATS_KEY, devid).
+ * The key type for tree items that are stored persistently, but do not need to
+ * exist for extended period of time. The items can exist in any tree.
+ *
+ * [subtype, BTRFS_TEMPORARY_ITEM_KEY, data]
+ *
+ * Existing items:
+ *
+ * - balance status item
+ * (BTRFS_BALANCE_OBJECTID, BTRFS_TEMPORARY_ITEM_KEY, 0)
+ */
+#define BTRFS_TEMPORARY_ITEM_KEY 248
+
+/*
+ * Obsolete name, see BTRFS_PERSISTENT_ITEM_KEY
+ */
+#define BTRFS_DEV_STATS_KEY 249
+
+/*
+ * The key type for tree items that are stored persistently and usually exist
+ * for a long period, eg. filesystem lifetime. The item kinds can be status
+ * information, stats or preference values. The item can exist in any tree.
+ *
+ * [subtype, BTRFS_PERSISTENT_ITEM_KEY, data]
+ *
+ * Existing items:
+ *
+ * - device statistics, store IO stats in the device tree, one key for all
+ * stats
+ * (BTRFS_DEV_STATS_OBJECTID, BTRFS_DEV_STATS_KEY, 0)
*/
-#define BTRFS_DEV_STATS_KEY 249
+#define BTRFS_PERSISTENT_ITEM_KEY 249
/*
* Persistantly stores the device replace state in the device tree.