[linux.git] / block / blk.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef BLK_INTERNAL_H
#define BLK_INTERNAL_H

#include <linux/idr.h>
#include <linux/blk-mq.h>
#include "blk-mq.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)

#ifdef CONFIG_DEBUG_FS
extern struct dentry *blk_debugfs_root;
#endif

struct blk_flush_queue {
	unsigned int		flush_queue_delayed:1;
	unsigned int		flush_pending_idx:1;
	unsigned int		flush_running_idx:1;
	unsigned long		flush_pending_since;
	struct list_head	flush_queue[2];
	struct list_head	flush_data_in_flight;
	struct request		*flush_rq;

	/*
	 * flush_rq shares tag with this rq, both can't be active
	 * at the same time
	 */
	struct request		*orig_rq;
	spinlock_t		mq_flush_lock;
};

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 struct blk_flush_queue *blk_get_flush_queue(
		struct request_queue *q, struct blk_mq_ctx *ctx)
{
	if (q->mq_ops)
		return blk_mq_map_queue(q, ctx->cpu)->fq;
	return q->fq;
}

static inline void __blk_get_queue(struct request_queue *q)
{
	kobject_get(&q->kobj);
}

struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q,
		int node, int cmd_size);
void blk_free_flush_queue(struct blk_flush_queue *q);

int blk_init_rl(struct request_list *rl, struct request_queue *q,
		gfp_t gfp_mask);
void blk_exit_rl(struct request_queue *q, struct request_list *rl);
void blk_rq_bio_prep(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_queue_free_tags(struct request_queue *q);
void blk_freeze_queue(struct request_queue *q);

static inline void blk_queue_enter_live(struct request_queue *q)
{
	/*
	 * Given that running in generic_make_request() context
	 * guarantees that a live reference against q_usage_counter has
	 * been established, further references under that same context
	 * need not check that the queue has been frozen (marked dead).
	 */
	percpu_ref_get(&q->q_usage_counter);
}

#ifdef CONFIG_BLK_DEV_INTEGRITY
void blk_flush_integrity(void);
bool __bio_integrity_endio(struct bio *);
static inline bool bio_integrity_endio(struct bio *bio)
{
	if (bio_integrity(bio))
		return __bio_integrity_endio(bio);
	return true;
}
#else
static inline void blk_flush_integrity(void)
{
}
static inline bool bio_integrity_endio(struct bio *bio)
{
	return true;
}
#endif

void blk_timeout_work(struct work_struct *work);
unsigned long blk_rq_timeout(unsigned long timeout);
void blk_add_timer(struct request *req);
void blk_delete_timer(struct request *);


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 bio_attempt_discard_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,
			    struct request **same_queue_rq);
unsigned int blk_plug_queued_count(struct request_queue *q);

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);

/*
 * EH timer and IO completion will both attempt to 'grab' the request, make
 * sure that only one of them succeeds. Steal the bottom bit of the
 * __deadline field for this.
 */
static inline int blk_mark_rq_complete(struct request *rq)
{
	return test_and_set_bit(0, &rq->__deadline);
}

static inline void blk_clear_rq_complete(struct request *rq)
{
	clear_bit(0, &rq->__deadline);
}

static inline bool blk_rq_is_complete(struct request *rq)
{
	return test_bit(0, &rq->__deadline);
}

/*
 * Internal elevator interface
 */
#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)

void blk_insert_flush(struct request *rq);

static inline void elv_activate_rq(struct request_queue *q, struct request *rq)
{
	struct elevator_queue *e = q->elevator;

	if (e->type->ops.sq.elevator_activate_req_fn)
		e->type->ops.sq.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.sq.elevator_deactivate_req_fn)
		e->type->ops.sq.elevator_deactivate_req_fn(q, rq);
}

int elv_register_queue(struct request_queue *q);
void elv_unregister_queue(struct request_queue *q);

struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);

#ifdef CONFIG_FAIL_IO_TIMEOUT
int blk_should_fake_timeout(struct request_queue *);
ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
ssize_t part_timeout_store(struct device *, struct device_attribute *,
				const char *, size_t);
#else
static inline int blk_should_fake_timeout(struct request_queue *q)
{
	return 0;
}
#endif

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);
struct request *attempt_back_merge(struct request_queue *q, struct request *rq);
struct request *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_rq_set_mixed_merge(struct request *rq);
bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);

void blk_queue_congestion_threshold(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
 * 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;
}

extern int blk_update_nr_requests(struct request_queue *, unsigned int);

/*
 * 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)
{
	return rq->rq_disk &&
	       (rq->rq_flags & RQF_IO_STAT) &&
		!blk_rq_is_passthrough(rq);
}

static inline void req_set_nomerge(struct request_queue *q, struct request *req)
{
	req->cmd_flags |= REQ_NOMERGE;
	if (req == q->last_merge)
		q->last_merge = NULL;
}

/*
 * Steal a bit from this field for legacy IO path atomic IO marking. Note that
 * setting the deadline clears the bottom bit, potentially clearing the
 * completed bit. The user has to be OK with this (current ones are fine).
 */
static inline void blk_rq_set_deadline(struct request *rq, unsigned long time)
{
	rq->__deadline = time & ~0x1UL;
}

static inline unsigned long blk_rq_deadline(struct request *rq)
{
	return rq->__deadline & ~0x1UL;
}

/*
 * 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);

/**
 * rq_ioc - determine io_context for request allocation
 * @bio: request being allocated is for this bio (can be %NULL)
 *
 * Determine io_context to use for request allocation for @bio.  May return
 * %NULL if %current->io_context doesn't exist.
 */
static inline struct io_context *rq_ioc(struct bio *bio)
{
#ifdef CONFIG_BLK_CGROUP
	if (bio && bio->bi_ioc)
		return bio->bi_ioc;
#endif
	return current->io_context;
}

/**
 * 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)
{
	WARN_ON_ONCE(irqs_disabled());
	if (unlikely(!current->io_context))
		create_task_io_context(current, gfp_mask, node);
	return current->io_context;
}

/*
 * Internal throttling interface
 */
#ifdef CONFIG_BLK_DEV_THROTTLING
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);
extern void blk_throtl_register_queue(struct request_queue *q);
#else /* CONFIG_BLK_DEV_THROTTLING */
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) { }
static inline void blk_throtl_register_queue(struct request_queue *q) { }
#endif /* CONFIG_BLK_DEV_THROTTLING */
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page);
extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
	const char *page, size_t count);
extern void blk_throtl_bio_endio(struct bio *bio);
extern void blk_throtl_stat_add(struct request *rq, u64 time);
#else
static inline void blk_throtl_bio_endio(struct bio *bio) { }
static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
#endif

#ifdef CONFIG_BOUNCE
extern int init_emergency_isa_pool(void);
extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
#else
static inline int init_emergency_isa_pool(void)
{
	return 0;
}
static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
{
}
#endif /* CONFIG_BOUNCE */

extern void blk_drain_queue(struct request_queue *q);

#endif /* BLK_INTERNAL_H */
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
8324aa91 JA	2	#ifndef BLK_INTERNAL_H
	3	#define BLK_INTERNAL_H
	4
a73f730d	5	#include <linux/idr.h>
f70ced09 ML	6	#include <linux/blk-mq.h>
f70ced09 ML	7	#include "blk-mq.h"
a73f730d	8
86db1e29 JA	9	/* Amount of time in which a process may batch requests */
	10	#define BLK_BATCH_TIME (HZ/50UL)
	11
	12	/* Number of requests a "batching" process may submit */
	13	#define BLK_BATCH_REQ 32
	14
0d2602ca JA	15	/* Max future timer expiry for timeouts */
	16	#define BLK_MAX_TIMEOUT (5 * HZ)
	17
18fbda91 OS	18	#ifdef CONFIG_DEBUG_FS
	19	extern struct dentry *blk_debugfs_root;
	20	#endif
	21
7c94e1c1 ML	22	struct blk_flush_queue {
	23	unsigned int flush_queue_delayed:1;
	24	unsigned int flush_pending_idx:1;
	25	unsigned int flush_running_idx:1;
	26	unsigned long flush_pending_since;
	27	struct list_head flush_queue[2];
	28	struct list_head flush_data_in_flight;
	29	struct request *flush_rq;
0048b483 ML	30
	31	/*
	32	* flush_rq shares tag with this rq, both can't be active
	33	* at the same time
	34	*/
	35	struct request *orig_rq;
7c94e1c1 ML	36	spinlock_t mq_flush_lock;
	37	};
	38
8324aa91	39	extern struct kmem_cache *blk_requestq_cachep;
320ae51f	40	extern struct kmem_cache *request_cachep;
8324aa91	41	extern struct kobj_type blk_queue_ktype;
a73f730d	42	extern struct ida blk_queue_ida;
8324aa91	43
7c94e1c1	44	static inline struct blk_flush_queue *blk_get_flush_queue(
e97c293c	45	struct request_queue q, struct blk_mq_ctx ctx)
7c94e1c1	46	{
7d7e0f90 CH	47	if (q->mq_ops)
	48	return blk_mq_map_queue(q, ctx->cpu)->fq;
	49	return q->fq;
7c94e1c1 ML	50	}
7c94e1c1 ML	51
09ac46c4 TH	52	static inline void __blk_get_queue(struct request_queue *q)
	53	{
	54	kobject_get(&q->kobj);
	55	}
	56
f70ced09 ML	57	struct blk_flush_queue blk_alloc_flush_queue(struct request_queue q,
	58	int node, int cmd_size);
	59	void blk_free_flush_queue(struct blk_flush_queue *q);
f3552655	60
5b788ce3 TH	61	int blk_init_rl(struct request_list rl, struct request_queue q,
5b788ce3 TH	62	gfp_t gfp_mask);
b425e504	63	void blk_exit_rl(struct request_queue q, struct request_list rl);
86db1e29 JA	64	void blk_rq_bio_prep(struct request_queue q, struct request rq,
86db1e29 JA	65	struct bio *bio);
d732580b TH	66	void blk_queue_bypass_start(struct request_queue *q);
d732580b TH	67	void blk_queue_bypass_end(struct request_queue *q);
8324aa91	68	void __blk_queue_free_tags(struct request_queue *q);
3ef28e83 DW	69	void blk_freeze_queue(struct request_queue *q);
	70
	71	static inline void blk_queue_enter_live(struct request_queue *q)
	72	{
	73	/*
	74	* Given that running in generic_make_request() context
	75	* guarantees that a live reference against q_usage_counter has
	76	* been established, further references under that same context
	77	* need not check that the queue has been frozen (marked dead).
	78	*/
	79	percpu_ref_get(&q->q_usage_counter);
	80	}
8324aa91	81
5a48fc14 DW	82	#ifdef CONFIG_BLK_DEV_INTEGRITY
5a48fc14 DW	83	void blk_flush_integrity(void);
7c20f116 CH	84	bool __bio_integrity_endio(struct bio *);
	85	static inline bool bio_integrity_endio(struct bio *bio)
	86	{
	87	if (bio_integrity(bio))
	88	return __bio_integrity_endio(bio);
	89	return true;
	90	}
5a48fc14 DW	91	#else
	92	static inline void blk_flush_integrity(void)
	93	{
	94	}
7c20f116 CH	95	static inline bool bio_integrity_endio(struct bio *bio)
	96	{
	97	return true;
	98	}
5a48fc14	99	#endif
8324aa91	100
287922eb	101	void blk_timeout_work(struct work_struct *work);
0d2602ca	102	unsigned long blk_rq_timeout(unsigned long timeout);
87ee7b11	103	void blk_add_timer(struct request *req);
242f9dcb	104	void blk_delete_timer(struct request *);
242f9dcb	105
320ae51f JA	106
	107	bool bio_attempt_front_merge(struct request_queue q, struct request req,
	108	struct bio *bio);
	109	bool bio_attempt_back_merge(struct request_queue q, struct request req,
	110	struct bio *bio);
1e739730 CH	111	bool bio_attempt_discard_merge(struct request_queue q, struct request req,
1e739730 CH	112	struct bio *bio);
320ae51f	113	bool blk_attempt_plug_merge(struct request_queue q, struct bio bio,
5b3f341f SL	114	unsigned int *request_count,
5b3f341f SL	115	struct request **same_queue_rq);
0809e3ac	116	unsigned int blk_plug_queued_count(struct request_queue *q);
320ae51f JA	117
	118	void blk_account_io_start(struct request *req, bool new_io);
	119	void blk_account_io_completion(struct request *req, unsigned int bytes);
	120	void blk_account_io_done(struct request *req);
	121
242f9dcb JA	122	/*
242f9dcb JA	123	* EH timer and IO completion will both attempt to 'grab' the request, make
e14575b3 JA	124	* sure that only one of them succeeds. Steal the bottom bit of the
e14575b3 JA	125	* __deadline field for this.
242f9dcb JA	126	*/
	127	static inline int blk_mark_rq_complete(struct request *rq)
	128	{
e14575b3	129	return test_and_set_bit(0, &rq->__deadline);
242f9dcb JA	130	}
	131
	132	static inline void blk_clear_rq_complete(struct request *rq)
	133	{
e14575b3 JA	134	clear_bit(0, &rq->__deadline);
	135	}
	136
	137	static inline bool blk_rq_is_complete(struct request *rq)
	138	{
	139	return test_bit(0, &rq->__deadline);
242f9dcb	140	}
86db1e29	141
158dbda0 TH	142	/*
	143	* Internal elevator interface
	144	*/
e8064021	145	#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
158dbda0	146
ae1b1539	147	void blk_insert_flush(struct request *rq);
dd831006	148
158dbda0 TH	149	static inline void elv_activate_rq(struct request_queue q, struct request rq)
	150	{
	151	struct elevator_queue *e = q->elevator;
	152
c51ca6cf JA	153	if (e->type->ops.sq.elevator_activate_req_fn)
c51ca6cf JA	154	e->type->ops.sq.elevator_activate_req_fn(q, rq);
158dbda0 TH	155	}
	156
	157	static inline void elv_deactivate_rq(struct request_queue q, struct request rq)
	158	{
	159	struct elevator_queue *e = q->elevator;
	160
c51ca6cf JA	161	if (e->type->ops.sq.elevator_deactivate_req_fn)
c51ca6cf JA	162	e->type->ops.sq.elevator_deactivate_req_fn(q, rq);
158dbda0 TH	163	}
158dbda0 TH	164
83d016ac BVA	165	int elv_register_queue(struct request_queue *q);
	166	void elv_unregister_queue(struct request_queue *q);
	167
807d4af2 CH	168	struct hd_struct __disk_get_part(struct gendisk disk, int partno);
807d4af2 CH	169
581d4e28 JA	170	#ifdef CONFIG_FAIL_IO_TIMEOUT
	171	int blk_should_fake_timeout(struct request_queue *);
	172	ssize_t part_timeout_show(struct device , struct device_attribute , char *);
	173	ssize_t part_timeout_store(struct device , struct device_attribute ,
	174	const char *, size_t);
	175	#else
	176	static inline int blk_should_fake_timeout(struct request_queue *q)
	177	{
	178	return 0;
	179	}
	180	#endif
	181
d6d48196 JA	182	int ll_back_merge_fn(struct request_queue q, struct request req,
	183	struct bio *bio);
	184	int ll_front_merge_fn(struct request_queue q, struct request req,
	185	struct bio *bio);
b973cb7e JA	186	struct request attempt_back_merge(struct request_queue q, struct request *rq);
b973cb7e JA	187	struct request attempt_front_merge(struct request_queue q, struct request *rq);
5e84ea3a JA	188	int blk_attempt_req_merge(struct request_queue q, struct request rq,
5e84ea3a JA	189	struct request *next);
d6d48196	190	void blk_recalc_rq_segments(struct request *rq);
80a761fd	191	void blk_rq_set_mixed_merge(struct request *rq);
050c8ea8	192	bool blk_rq_merge_ok(struct request rq, struct bio bio);
34fe7c05	193	enum elv_merge blk_try_merge(struct request rq, struct bio bio);
d6d48196	194
8324aa91 JA	195	void blk_queue_congestion_threshold(struct request_queue *q);
8324aa91 JA	196
ff88972c AB	197	int blk_dev_init(void);
ff88972c AB	198
f253b86b	199
8324aa91 JA	200	/*
	201	* Return the threshold (number of used requests) at which the queue is
	202	* considered to be congested. It include a little hysteresis to keep the
	203	* context switch rate down.
	204	*/
	205	static inline int queue_congestion_on_threshold(struct request_queue *q)
	206	{
	207	return q->nr_congestion_on;
	208	}
	209
	210	/*
	211	* The threshold at which a queue is considered to be uncongested
	212	*/
	213	static inline int queue_congestion_off_threshold(struct request_queue *q)
	214	{
	215	return q->nr_congestion_off;
	216	}
	217
e3a2b3f9 JA	218	extern int blk_update_nr_requests(struct request_queue *, unsigned int);
e3a2b3f9 JA	219
c2553b58 JA	220	/*
	221	* Contribute to IO statistics IFF:
	222	*
	223	* a) it's attached to a gendisk, and
	224	* b) the queue had IO stats enabled when this request was started, and
e2a60da7	225	* c) it's a file system request
c2553b58	226	*/
26308eab	227	static inline int blk_do_io_stat(struct request *rq)
fb8ec18c	228	{
33659ebb	229	return rq->rq_disk &&
e8064021	230	(rq->rq_flags & RQF_IO_STAT) &&
57292b58	231	!blk_rq_is_passthrough(rq);
fb8ec18c JA	232	}
fb8ec18c JA	233
6cf7677f CH	234	static inline void req_set_nomerge(struct request_queue q, struct request req)
	235	{
	236	req->cmd_flags \|= REQ_NOMERGE;
	237	if (req == q->last_merge)
	238	q->last_merge = NULL;
	239	}
	240
0a72e7f4 JA	241	/*
	242	* Steal a bit from this field for legacy IO path atomic IO marking. Note that
	243	* setting the deadline clears the bottom bit, potentially clearing the
	244	* completed bit. The user has to be OK with this (current ones are fine).
	245	*/
	246	static inline void blk_rq_set_deadline(struct request *rq, unsigned long time)
	247	{
	248	rq->__deadline = time & ~0x1UL;
	249	}
	250
	251	static inline unsigned long blk_rq_deadline(struct request *rq)
	252	{
	253	return rq->__deadline & ~0x1UL;
	254	}
	255
f2dbd76a TH	256	/*
	257	* Internal io_context interface
	258	*/
	259	void get_io_context(struct io_context *ioc);
47fdd4ca	260	struct io_cq ioc_lookup_icq(struct io_context ioc, struct request_queue *q);
24acfc34 TH	261	struct io_cq ioc_create_icq(struct io_context ioc, struct request_queue *q,
24acfc34 TH	262	gfp_t gfp_mask);
7e5a8794	263	void ioc_clear_queue(struct request_queue *q);
f2dbd76a	264
24acfc34	265	int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
f2dbd76a	266
c23ecb42 JA	267	/**
	268	* rq_ioc - determine io_context for request allocation
	269	* @bio: request being allocated is for this bio (can be %NULL)
	270	*
	271	* Determine io_context to use for request allocation for @bio. May return
	272	* %NULL if %current->io_context doesn't exist.
	273	*/
	274	static inline struct io_context rq_ioc(struct bio bio)
	275	{
	276	#ifdef CONFIG_BLK_CGROUP
	277	if (bio && bio->bi_ioc)
	278	return bio->bi_ioc;
	279	#endif
	280	return current->io_context;
	281	}
	282
f2dbd76a TH	283	/**
f2dbd76a TH	284	* create_io_context - try to create task->io_context
f2dbd76a TH	285	* @gfp_mask: allocation mask
	286	* @node: allocation node
	287	*
24acfc34 TH	288	* If %current->io_context is %NULL, allocate a new io_context and install
	289	* it. Returns the current %current->io_context which may be %NULL if
	290	* allocation failed.
f2dbd76a TH	291	*
f2dbd76a TH	292	* Note that this function can't be called with IRQ disabled because
24acfc34	293	* task_lock which protects %current->io_context is IRQ-unsafe.
f2dbd76a	294	*/
24acfc34	295	static inline struct io_context *create_io_context(gfp_t gfp_mask, int node)
f2dbd76a TH	296	{
f2dbd76a TH	297	WARN_ON_ONCE(irqs_disabled());
24acfc34 TH	298	if (unlikely(!current->io_context))
	299	create_task_io_context(current, gfp_mask, node);
	300	return current->io_context;
f2dbd76a TH	301	}
	302
	303	/*
	304	* Internal throttling interface
	305	*/
bc9fcbf9	306	#ifdef CONFIG_BLK_DEV_THROTTLING
c9a929dd	307	extern void blk_throtl_drain(struct request_queue *q);
bc9fcbf9 TH	308	extern int blk_throtl_init(struct request_queue *q);
bc9fcbf9 TH	309	extern void blk_throtl_exit(struct request_queue *q);
d61fcfa4	310	extern void blk_throtl_register_queue(struct request_queue *q);
bc9fcbf9	311	#else /* CONFIG_BLK_DEV_THROTTLING */
c9a929dd	312	static inline void blk_throtl_drain(struct request_queue *q) { }
bc9fcbf9 TH	313	static inline int blk_throtl_init(struct request_queue *q) { return 0; }
bc9fcbf9 TH	314	static inline void blk_throtl_exit(struct request_queue *q) { }
d61fcfa4	315	static inline void blk_throtl_register_queue(struct request_queue *q) { }
bc9fcbf9	316	#endif /* CONFIG_BLK_DEV_THROTTLING */
297e3d85 SL	317	#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
	318	extern ssize_t blk_throtl_sample_time_show(struct request_queue q, char page);
	319	extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
	320	const char *page, size_t count);
9e234eea	321	extern void blk_throtl_bio_endio(struct bio *bio);
b9147dd1	322	extern void blk_throtl_stat_add(struct request *rq, u64 time);
9e234eea SL	323	#else
9e234eea SL	324	static inline void blk_throtl_bio_endio(struct bio *bio) { }
b9147dd1	325	static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
297e3d85	326	#endif
bc9fcbf9	327
3bce016a CH	328	#ifdef CONFIG_BOUNCE
	329	extern int init_emergency_isa_pool(void);
	330	extern void blk_queue_bounce(struct request_queue q, struct bio *bio);
	331	#else
	332	static inline int init_emergency_isa_pool(void)
	333	{
	334	return 0;
	335	}
	336	static inline void blk_queue_bounce(struct request_queue q, struct bio *bio)
	337	{
	338	}
	339	#endif /* CONFIG_BOUNCE */
	340
454be724 ML	341	extern void blk_drain_queue(struct request_queue *q);
454be724 ML	342
bc9fcbf9	343	#endif /* BLK_INTERNAL_H */