blk-mq: new multi-queue block IO queueing mechanism

[linux-2.6-block.git] / include / linux / blkdev.h

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 0a8da96274c3541a46d886b5946233b768fe831e..f26ec20f635476a88c8879baad16a5a908433fa7 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -8,6 +8,7 @@
 #include <linux/major.h>
 #include <linux/genhd.h>
 #include <linux/list.h>
+#include <linux/llist.h>
 #include <linux/timer.h>
 #include <linux/workqueue.h>
 #include <linux/pagemap.h>
@@ -94,10 +95,17 @@ enum rq_cmd_type_bits {
  * as well!
  */
 struct request {
-       struct list_head queuelist;
-       struct call_single_data csd;
+       union {
+               struct list_head queuelist;
+               struct llist_node ll_list;
+       };
+       union {
+               struct call_single_data csd;
+               struct work_struct mq_flush_data;
+       };
 
        struct request_queue *q;
+       struct blk_mq_ctx *mq_ctx;
 
        u64 cmd_flags;
        enum rq_cmd_type_bits cmd_type;
@@ -213,6 +221,8 @@ struct request_pm_state
 
 #include <linux/elevator.h>
 
+struct blk_queue_ctx;
+
 typedef void (request_fn_proc) (struct request_queue *q);
 typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
@@ -311,6 +321,18 @@ struct request_queue {
        dma_drain_needed_fn     *dma_drain_needed;
        lld_busy_fn             *lld_busy_fn;
 
+       struct blk_mq_ops       *mq_ops;
+
+       unsigned int            *mq_map;
+
+       /* sw queues */
+       struct blk_mq_ctx       *queue_ctx;
+       unsigned int            nr_queues;
+
+       /* hw dispatch queues */
+       struct blk_mq_hw_ctx    **queue_hw_ctx;
+       unsigned int            nr_hw_queues;
+
        /*
         * Dispatch queue sorting
         */
@@ -359,6 +381,11 @@ struct request_queue {
         */
        struct kobject kobj;
 
+       /*
+        * mq queue kobject
+        */
+       struct kobject mq_kobj;
+
 #ifdef CONFIG_PM_RUNTIME
        struct device           *dev;
        int                     rpm_status;
@@ -423,7 +450,13 @@ struct request_queue {
        unsigned long           flush_pending_since;
        struct list_head        flush_queue[2];
        struct list_head        flush_data_in_flight;
-       struct request          flush_rq;
+       union {
+               struct request  flush_rq;
+               struct {
+                       spinlock_t mq_flush_lock;
+                       struct work_struct mq_flush_work;
+               };
+       };
 
        struct mutex            sysfs_lock;
 
@@ -435,14 +468,14 @@ struct request_queue {
        struct bsg_class_device bsg_dev;
 #endif
 
-#ifdef CONFIG_BLK_CGROUP
-       struct list_head        all_q_node;
-#endif
 #ifdef CONFIG_BLK_DEV_THROTTLING
        /* Throttle data */
        struct throtl_data *td;
 #endif
        struct rcu_head         rcu_head;
+       wait_queue_head_t       mq_freeze_wq;
+       struct percpu_counter   mq_usage_counter;
+       struct list_head        all_q_node;
 };
 
 #define QUEUE_FLAG_QUEUED      1       /* uses generic tag queueing */
@@ -465,6 +498,7 @@ struct request_queue {
 #define QUEUE_FLAG_SECDISCARD  17      /* supports SECDISCARD */
 #define QUEUE_FLAG_SAME_FORCE  18      /* force complete on same CPU */
 #define QUEUE_FLAG_DEAD        19      /* queue tear-down finished */
+#define QUEUE_FLAG_INIT_DONE   20      /* queue is initialized */
 
 #define QUEUE_FLAG_DEFAULT     ((1 << QUEUE_FLAG_IO_STAT) |            \
                                 (1 << QUEUE_FLAG_STACKABLE)    |       \
@@ -537,6 +571,7 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
 #define blk_queue_dying(q)     test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
 #define blk_queue_dead(q)      test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
 #define blk_queue_bypass(q)    test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
+#define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
 #define blk_queue_nomerges(q)  test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
 #define blk_queue_noxmerges(q) \
        test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
@@ -1011,6 +1046,7 @@ static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
 struct blk_plug {
        unsigned long magic; /* detect uninitialized use-cases */
        struct list_head list; /* requests */
+       struct list_head mq_list; /* blk-mq requests */
        struct list_head cb_list; /* md requires an unplug callback */
 };
 #define BLK_MAX_REQUEST_COUNT 16
@@ -1048,7 +1084,10 @@ static inline bool blk_needs_flush_plug(struct task_struct *tsk)
 {
        struct blk_plug *plug = tsk->plug;
 
-       return plug && (!list_empty(&plug->list) || !list_empty(&plug->cb_list));
+       return plug &&
+               (!list_empty(&plug->list) ||
+                !list_empty(&plug->mq_list) ||
+                !list_empty(&plug->cb_list));
 }
 
 /*
@@ -1323,6 +1362,7 @@ static inline void put_dev_sector(Sector p)
 
 struct work_struct;
 int kblockd_schedule_work(struct request_queue *q, struct work_struct *work);
+int kblockd_schedule_delayed_work(struct request_queue *q, struct delayed_work *dwork, unsigned long delay);
 
 #ifdef CONFIG_BLK_CGROUP
 /*