1 files changed, 165 insertions, 29 deletions

diff --git a/block/blk.h b/block/blk.h
index 0dce92c3749..6748c4f8d7a 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -1,37 +1,72 @@
 #ifndef BLK_INTERNAL_H
 #define BLK_INTERNAL_H
 
+#include <linux/idr.h>
+
 /* Amount of time in which a process may batch requests */
 #define BLK_BATCH_TIME	(HZ/50UL)
 
 /* Number of requests a "batching" process may submit */
 #define BLK_BATCH_REQ	32
 
+/* Max future timer expiry for timeouts */
+#define BLK_MAX_TIMEOUT		(5 * HZ)
+
 extern struct kmem_cache *blk_requestq_cachep;
+extern struct kmem_cache *request_cachep;
 extern struct kobj_type blk_queue_ktype;
+extern struct ida blk_queue_ida;
+
+static inline void __blk_get_queue(struct request_queue *q)
+{
+	kobject_get(&q->kobj);
+}
 
+int blk_init_rl(struct request_list *rl, struct request_queue *q,
+		gfp_t gfp_mask);
+void blk_exit_rl(struct request_list *rl);
 void init_request_from_bio(struct request *req, struct bio *bio);
 void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
 			struct bio *bio);
+int blk_rq_append_bio(struct request_queue *q, struct request *rq,
+		      struct bio *bio);
+void blk_queue_bypass_start(struct request_queue *q);
+void blk_queue_bypass_end(struct request_queue *q);
+void blk_dequeue_request(struct request *rq);
 void __blk_queue_free_tags(struct request_queue *q);
+bool __blk_end_bidi_request(struct request *rq, int error,
+			    unsigned int nr_bytes, unsigned int bidi_bytes);
 
-void blk_unplug_work(struct work_struct *work);
-void blk_unplug_timeout(unsigned long data);
 void blk_rq_timed_out_timer(unsigned long data);
+void blk_rq_check_expired(struct request *rq, unsigned long *next_timeout,
+			  unsigned int *next_set);
+unsigned long blk_rq_timeout(unsigned long timeout);
+void blk_add_timer(struct request *req);
 void blk_delete_timer(struct request *);
-void blk_add_timer(struct request *);
-void __generic_unplug_device(struct request_queue *);
+
+
+bool bio_attempt_front_merge(struct request_queue *q, struct request *req,
+			     struct bio *bio);
+bool bio_attempt_back_merge(struct request_queue *q, struct request *req,
+			    struct bio *bio);
+bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
+			    unsigned int *request_count);
+
+void blk_account_io_start(struct request *req, bool new_io);
+void blk_account_io_completion(struct request *req, unsigned int bytes);
+void blk_account_io_done(struct request *req);
 
 /*
  * Internal atomic flags for request handling
  */
 enum rq_atomic_flags {
 	REQ_ATOM_COMPLETE = 0,
+	REQ_ATOM_STARTED,
 };
 
 /*
  * EH timer and IO completion will both attempt to 'grab' the request, make
- * sure that only one of them suceeds
+ * sure that only one of them succeeds
  */
 static inline int blk_mark_rq_complete(struct request *rq)
 {
@@ -43,6 +78,65 @@ static inline void blk_clear_rq_complete(struct request *rq)
 	clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
 }
 
+/*
+ * Internal elevator interface
+ */
+#define ELV_ON_HASH(rq) ((rq)->cmd_flags & REQ_HASHED)
+
+void blk_insert_flush(struct request *rq);
+
+static inline struct request *__elv_next_request(struct request_queue *q)
+{
+	struct request *rq;
+
+	while (1) {
+		if (!list_empty(&q->queue_head)) {
+			rq = list_entry_rq(q->queue_head.next);
+			return rq;
+		}
+
+		/*
+		 * Flush request is running and flush request isn't queueable
+		 * in the drive, we can hold the queue till flush request is
+		 * finished. Even we don't do this, driver can't dispatch next
+		 * requests and will requeue them. And this can improve
+		 * throughput too. For example, we have request flush1, write1,
+		 * flush 2. flush1 is dispatched, then queue is hold, write1
+		 * isn't inserted to queue. After flush1 is finished, flush2
+		 * will be dispatched. Since disk cache is already clean,
+		 * flush2 will be finished very soon, so looks like flush2 is
+		 * folded to flush1.
+		 * Since the queue is hold, a flag is set to indicate the queue
+		 * should be restarted later. Please see flush_end_io() for
+		 * details.
+		 */
+		if (q->flush_pending_idx != q->flush_running_idx &&
+				!queue_flush_queueable(q)) {
+			q->flush_queue_delayed = 1;
+			return NULL;
+		}
+		if (unlikely(blk_queue_bypass(q)) ||
+		    !q->elevator->type->ops.elevator_dispatch_fn(q, 0))
+			return NULL;
+	}
+}
+
+static inline void elv_activate_rq(struct request_queue *q, struct request *rq)
+{
+	struct elevator_queue *e = q->elevator;
+
+	if (e->type->ops.elevator_activate_req_fn)
+		e->type->ops.elevator_activate_req_fn(q, rq);
+}
+
+static inline void elv_deactivate_rq(struct request_queue *q, struct request *rq)
+{
+	struct elevator_queue *e = q->elevator;
+
+	if (e->type->ops.elevator_deactivate_req_fn)
+		e->type->ops.elevator_deactivate_req_fn(q, rq);
+}
+
 #ifdef CONFIG_FAIL_IO_TIMEOUT
 int blk_should_fake_timeout(struct request_queue *);
 ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
@@ -55,21 +149,26 @@ static inline int blk_should_fake_timeout(struct request_queue *q)
 }
 #endif
 
-struct io_context *current_io_context(gfp_t gfp_flags, int node);
-
 int ll_back_merge_fn(struct request_queue *q, struct request *req,
 		     struct bio *bio);
 int ll_front_merge_fn(struct request_queue *q, struct request *req, 
 		      struct bio *bio);
 int attempt_back_merge(struct request_queue *q, struct request *rq);
 int attempt_front_merge(struct request_queue *q, struct request *rq);
+int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
+				struct request *next);
 void blk_recalc_rq_segments(struct request *rq);
-void blk_recalc_rq_sectors(struct request *rq, int nsect);
+void blk_rq_set_mixed_merge(struct request *rq);
+bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
+int blk_try_merge(struct request *rq, struct bio *bio);
 
 void blk_queue_congestion_threshold(struct request_queue *q);
 
+void __blk_run_queue_uncond(struct request_queue *q);
+
 int blk_dev_init(void);
 
+
 /*
  * Return the threshold (number of used requests) at which the queue is
  * considered to be congested.  It include a little hysteresis to keep the
@@ -88,32 +187,69 @@ static inline int queue_congestion_off_threshold(struct request_queue *q)
 	return q->nr_congestion_off;
 }
 
-#if defined(CONFIG_BLK_DEV_INTEGRITY)
+extern int blk_update_nr_requests(struct request_queue *, unsigned int);
 
-#define rq_for_each_integrity_segment(bvl, _rq, _iter)		\
-	__rq_for_each_bio(_iter.bio, _rq)			\
-		bip_for_each_vec(bvl, _iter.bio->bi_integrity, _iter.i)
-
-#endif /* BLK_DEV_INTEGRITY */
-
-static inline int blk_cpu_to_group(int cpu)
+/*
+ * Contribute to IO statistics IFF:
+ *
+ *	a) it's attached to a gendisk, and
+ *	b) the queue had IO stats enabled when this request was started, and
+ *	c) it's a file system request
+ */
+static inline int blk_do_io_stat(struct request *rq)
 {
-#ifdef CONFIG_SCHED_MC
-	const struct cpumask *mask = cpu_coregroup_mask(cpu);
-	return cpumask_first(mask);
-#elif defined(CONFIG_SCHED_SMT)
-	return first_cpu(per_cpu(cpu_sibling_map, cpu));
-#else
-	return cpu;
-#endif
+	return rq->rq_disk &&
+	       (rq->cmd_flags & REQ_IO_STAT) &&
+		(rq->cmd_type == REQ_TYPE_FS);
 }
 
-static inline int blk_do_io_stat(struct request_queue *q)
+/*
+ * Internal io_context interface
+ */
+void get_io_context(struct io_context *ioc);
+struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q);
+struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
+			     gfp_t gfp_mask);
+void ioc_clear_queue(struct request_queue *q);
+
+int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
+
+/**
+ * create_io_context - try to create task->io_context
+ * @gfp_mask: allocation mask
+ * @node: allocation node
+ *
+ * If %current->io_context is %NULL, allocate a new io_context and install
+ * it.  Returns the current %current->io_context which may be %NULL if
+ * allocation failed.
+ *
+ * Note that this function can't be called with IRQ disabled because
+ * task_lock which protects %current->io_context is IRQ-unsafe.
+ */
+static inline struct io_context *create_io_context(gfp_t gfp_mask, int node)
 {
-	if (q)
-		return blk_queue_io_stat(q);
+	WARN_ON_ONCE(irqs_disabled());
+	if (unlikely(!current->io_context))
+		create_task_io_context(current, gfp_mask, node);
+	return current->io_context;
+}
 
-	return 0;
+/*
+ * Internal throttling interface
+ */
+#ifdef CONFIG_BLK_DEV_THROTTLING
+extern bool blk_throtl_bio(struct request_queue *q, struct bio *bio);
+extern void blk_throtl_drain(struct request_queue *q);
+extern int blk_throtl_init(struct request_queue *q);
+extern void blk_throtl_exit(struct request_queue *q);
+#else /* CONFIG_BLK_DEV_THROTTLING */
+static inline bool blk_throtl_bio(struct request_queue *q, struct bio *bio)
+{
+	return false;
 }
+static inline void blk_throtl_drain(struct request_queue *q) { }
+static inline int blk_throtl_init(struct request_queue *q) { return 0; }
+static inline void blk_throtl_exit(struct request_queue *q) { }
+#endif /* CONFIG_BLK_DEV_THROTTLING */
 
-#endif
+#endif /* BLK_INTERNAL_H */