[mirror_ubuntu-artful-kernel.git] / block / blk.h

#ifndef BLK_INTERNAL_H
#define BLK_INTERNAL_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

extern struct kmem_cache *blk_requestq_cachep;
extern struct kobj_type blk_queue_ktype;

void rq_init(struct request_queue *q, struct request *rq);
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 ll_back_merge_fn(struct request_queue *q, struct request *req,
		     struct bio *bio);
void __blk_queue_free_tags(struct request_queue *q);

void blk_unplug_work(struct work_struct *work);
void blk_unplug_timeout(unsigned long data);

struct io_context *current_io_context(gfp_t gfp_flags, int node);

void blk_queue_congestion_threshold(struct request_queue *q);

/*
 * Return the threshold (number of used requests) at which the queue is
 * considered to be congested.  It include a little hysteresis to keep the
 * context switch rate down.
 */
static inline int queue_congestion_on_threshold(struct request_queue *q)
{
	return q->nr_congestion_on;
}

/*
 * The threshold at which a queue is considered to be uncongested
 */
static inline int queue_congestion_off_threshold(struct request_queue *q)
{
	return q->nr_congestion_off;
}

#endif
Commit	Line	Data
8324aa91 JA	1	#ifndef BLK_INTERNAL_H
	2	#define BLK_INTERNAL_H
	3
86db1e29 JA	4	/* Amount of time in which a process may batch requests */
	5	#define BLK_BATCH_TIME (HZ/50UL)
	6
	7	/* Number of requests a "batching" process may submit */
	8	#define BLK_BATCH_REQ 32
	9
8324aa91 JA	10	extern struct kmem_cache *blk_requestq_cachep;
	11	extern struct kobj_type blk_queue_ktype;
	12
86db1e29 JA	13	void rq_init(struct request_queue q, struct request rq);
	14	void init_request_from_bio(struct request req, struct bio bio);
	15	void blk_rq_bio_prep(struct request_queue q, struct request rq,
	16	struct bio *bio);
	17	int ll_back_merge_fn(struct request_queue q, struct request req,
	18	struct bio *bio);
8324aa91 JA	19	void __blk_queue_free_tags(struct request_queue *q);
8324aa91 JA	20
86db1e29 JA	21	void blk_unplug_work(struct work_struct *work);
	22	void blk_unplug_timeout(unsigned long data);
	23
	24	struct io_context *current_io_context(gfp_t gfp_flags, int node);
	25
8324aa91 JA	26	void blk_queue_congestion_threshold(struct request_queue *q);
	27
	28	/*
	29	* Return the threshold (number of used requests) at which the queue is
	30	* considered to be congested. It include a little hysteresis to keep the
	31	* context switch rate down.
	32	*/
	33	static inline int queue_congestion_on_threshold(struct request_queue *q)
	34	{
	35	return q->nr_congestion_on;
	36	}
	37
	38	/*
	39	* The threshold at which a queue is considered to be uncongested
	40	*/
	41	static inline int queue_congestion_off_threshold(struct request_queue *q)
	42	{
	43	return q->nr_congestion_off;
	44	}
	45
	46	#endif