+#if defined(CONFIG_BLK_CGROUP) || defined(CONFIG_BLK_CGROUP_MODULE)
+
+#ifndef CONFIG_BLK_CGROUP
+/* When blk-cgroup is a module, its subsys_id isn't a compile-time constant */
+extern struct cgroup_subsys blkio_subsys;
+#define blkio_subsys_id blkio_subsys.subsys_id
+#endif
+
+enum stat_type {
+ /* Total time spent (in ns) between request dispatch to the driver and
+ * request completion for IOs doen by this cgroup. This may not be
+ * accurate when NCQ is turned on. */
+ BLKIO_STAT_SERVICE_TIME = 0,
+ /* Total bytes transferred */
+ BLKIO_STAT_SERVICE_BYTES,
+ /* Total IOs serviced, post merge */
+ BLKIO_STAT_SERVICED,
+ /* Total time spent waiting in scheduler queue in ns */
+ BLKIO_STAT_WAIT_TIME,
+ /* Number of IOs merged */
+ BLKIO_STAT_MERGED,
+ /* Number of IOs queued up */
+ BLKIO_STAT_QUEUED,
+ /* All the single valued stats go below this */
+ BLKIO_STAT_TIME,
+ BLKIO_STAT_SECTORS,
+#ifdef CONFIG_DEBUG_BLK_CGROUP
+ BLKIO_STAT_AVG_QUEUE_SIZE,
+ BLKIO_STAT_IDLE_TIME,
+ BLKIO_STAT_EMPTY_TIME,
+ BLKIO_STAT_GROUP_WAIT_TIME,
+ BLKIO_STAT_DEQUEUE
+#endif
+};
+
+enum stat_sub_type {
+ BLKIO_STAT_READ = 0,
+ BLKIO_STAT_WRITE,
+ BLKIO_STAT_SYNC,
+ BLKIO_STAT_ASYNC,
+ BLKIO_STAT_TOTAL
+};
+
+/* blkg state flags */
+enum blkg_state_flags {
+ BLKG_waiting = 0,
+ BLKG_idling,
+ BLKG_empty,
+};