[linux-block.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 <xen/xen.h>
#include "blk-mq.h"
#include "blk-mq-sched.h"

/* 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;
	blk_status_t 		rq_status;
	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 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)
{
	return blk_mq_map_queue(q, REQ_OP_FLUSH, ctx)->fq;
}

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

static inline bool
is_flush_rq(struct request *req, struct blk_mq_hw_ctx *hctx)
{
	return hctx->fq->flush_rq == req;
}

struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q,
		int node, int cmd_size, gfp_t flags);
void blk_free_flush_queue(struct blk_flush_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);
}

static inline bool biovec_phys_mergeable(struct request_queue *q,
		struct bio_vec *vec1, struct bio_vec *vec2)
{
	unsigned long mask = queue_segment_boundary(q);
	phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
	phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;

	if (addr1 + vec1->bv_len != addr2)
		return false;
	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
		return false;
	if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
		return false;
	return true;
}

static inline bool __bvec_gap_to_prev(struct request_queue *q,
		struct bio_vec *bprv, unsigned int offset)
{
	return (offset & queue_virt_boundary(q)) ||
		((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
}

/*
 * Check if adding a bio_vec after bprv with offset would create a gap in
 * the SG list. Most drivers don't care about this, but some do.
 */
static inline bool bvec_gap_to_prev(struct request_queue *q,
		struct bio_vec *bprv, unsigned int offset)
{
	if (!queue_virt_boundary(q))
		return false;
	return __bvec_gap_to_prev(q, bprv, offset);
}

static inline void blk_rq_bio_prep(struct request *rq, struct bio *bio,
		unsigned int nr_segs)
{
	rq->nr_phys_segments = nr_segs;
	rq->__data_len = bio->bi_iter.bi_size;
	rq->bio = rq->biotail = bio;
	rq->ioprio = bio_prio(bio);

	if (bio->bi_disk)
		rq->rq_disk = bio->bi_disk;
}

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

static inline bool integrity_req_gap_back_merge(struct request *req,
		struct bio *next)
{
	struct bio_integrity_payload *bip = bio_integrity(req->bio);
	struct bio_integrity_payload *bip_next = bio_integrity(next);

	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
				bip_next->bip_vec[0].bv_offset);
}

static inline bool integrity_req_gap_front_merge(struct request *req,
		struct bio *bio)
{
	struct bio_integrity_payload *bip = bio_integrity(bio);
	struct bio_integrity_payload *bip_next = bio_integrity(req->bio);

	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
				bip_next->bip_vec[0].bv_offset);
}
#else /* CONFIG_BLK_DEV_INTEGRITY */
static inline bool integrity_req_gap_back_merge(struct request *req,
		struct bio *next)
{
	return false;
}
static inline bool integrity_req_gap_front_merge(struct request *req,
		struct bio *bio)
{
	return false;
}

static inline void blk_flush_integrity(void)
{
}
static inline bool bio_integrity_endio(struct bio *bio)
{
	return true;
}
static inline void bio_integrity_free(struct bio *bio)
{
}
#endif /* CONFIG_BLK_DEV_INTEGRITY */

unsigned long blk_rq_timeout(unsigned long timeout);
void blk_add_timer(struct request *req);

bool bio_attempt_front_merge(struct request *req, struct bio *bio,
		unsigned int nr_segs);
bool bio_attempt_back_merge(struct request *req, struct bio *bio,
		unsigned int nr_segs);
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 nr_segs, struct request **same_queue_rq);

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, u64 now);

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

void blk_insert_flush(struct request *rq);

void elevator_init_mq(struct request_queue *q);
int elevator_switch_mq(struct request_queue *q,
			      struct elevator_type *new_e);
void __elevator_exit(struct request_queue *, struct elevator_queue *);
int elv_register_queue(struct request_queue *q, bool uevent);
void elv_unregister_queue(struct request_queue *q);

static inline void elevator_exit(struct request_queue *q,
		struct elevator_queue *e)
{
	lockdep_assert_held(&q->sysfs_lock);

	blk_mq_sched_free_requests(q);
	__elevator_exit(q, e);
}

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

void __blk_queue_split(struct request_queue *q, struct bio **bio,
		unsigned int *nr_segs);
int ll_back_merge_fn(struct request *req, struct bio *bio,
		unsigned int nr_segs);
int ll_front_merge_fn(struct request *req,  struct bio *bio,
		unsigned int nr_segs);
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);
unsigned int 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);

int blk_dev_init(void);

/*
 * 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
 */
static inline bool blk_do_io_stat(struct request *rq)
{
	return rq->rq_disk && (rq->rq_flags & RQF_IO_STAT);
}

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;
}

/*
 * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
 * is defined as 'unsigned int', meantime it has to aligned to with logical
 * block size which is the minimum accepted unit by hardware.
 */
static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
{
	return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
}

/*
 * 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)
{
	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 */

#ifdef CONFIG_BLK_CGROUP_IOLATENCY
extern int blk_iolatency_init(struct request_queue *q);
#else
static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
#endif

struct bio *blk_next_bio(struct bio *bio, unsigned int nr_pages, gfp_t gfp);

#ifdef CONFIG_BLK_DEV_ZONED
void blk_queue_free_zone_bitmaps(struct request_queue *q);
#else
static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
#endif

#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	6	#include <linux/blk-mq.h>
c39ae60d	7	#include <xen/xen.h>
f70ced09	8	#include "blk-mq.h"
c3e22192	9	#include "blk-mq-sched.h"
a73f730d	10
0d2602ca JA	11	/* Max future timer expiry for timeouts */
	12	#define BLK_MAX_TIMEOUT (5 * HZ)
	13
18fbda91 OS	14	#ifdef CONFIG_DEBUG_FS
	15	extern struct dentry *blk_debugfs_root;
	16	#endif
	17
7c94e1c1 ML	18	struct blk_flush_queue {
	19	unsigned int flush_queue_delayed:1;
	20	unsigned int flush_pending_idx:1;
	21	unsigned int flush_running_idx:1;
8d699663	22	blk_status_t rq_status;
7c94e1c1 ML	23	unsigned long flush_pending_since;
	24	struct list_head flush_queue[2];
	25	struct list_head flush_data_in_flight;
	26	struct request *flush_rq;
0048b483 ML	27
	28	/*
	29	* flush_rq shares tag with this rq, both can't be active
	30	* at the same time
	31	*/
	32	struct request *orig_rq;
7c94e1c1 ML	33	spinlock_t mq_flush_lock;
	34	};
	35
8324aa91 JA	36	extern struct kmem_cache *blk_requestq_cachep;
8324aa91 JA	37	extern struct kobj_type blk_queue_ktype;
a73f730d	38	extern struct ida blk_queue_ida;
8324aa91	39
f9afca4d JA	40	static inline struct blk_flush_queue *
f9afca4d JA	41	blk_get_flush_queue(struct request_queue q, struct blk_mq_ctx ctx)
7c94e1c1	42	{
8ccdf4a3	43	return blk_mq_map_queue(q, REQ_OP_FLUSH, ctx)->fq;
7c94e1c1 ML	44	}
7c94e1c1 ML	45
09ac46c4 TH	46	static inline void __blk_get_queue(struct request_queue *q)
	47	{
	48	kobject_get(&q->kobj);
	49	}
	50
8d699663 YY	51	static inline bool
	52	is_flush_rq(struct request req, struct blk_mq_hw_ctx hctx)
	53	{
	54	return hctx->fq->flush_rq == req;
	55	}
	56
f70ced09	57	struct blk_flush_queue blk_alloc_flush_queue(struct request_queue q,
5b202853	58	int node, int cmd_size, gfp_t flags);
f70ced09	59	void blk_free_flush_queue(struct blk_flush_queue *q);
f3552655	60
3ef28e83 DW	61	void blk_freeze_queue(struct request_queue *q);
	62
	63	static inline void blk_queue_enter_live(struct request_queue *q)
	64	{
	65	/*
	66	* Given that running in generic_make_request() context
	67	* guarantees that a live reference against q_usage_counter has
	68	* been established, further references under that same context
	69	* need not check that the queue has been frozen (marked dead).
	70	*/
	71	percpu_ref_get(&q->q_usage_counter);
	72	}
8324aa91	73
3dccdae5 CH	74	static inline bool biovec_phys_mergeable(struct request_queue *q,
3dccdae5 CH	75	struct bio_vec vec1, struct bio_vec vec2)
6a9f5f24	76	{
3dccdae5	77	unsigned long mask = queue_segment_boundary(q);
6e768461 CH	78	phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
6e768461 CH	79	phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
3dccdae5 CH	80
3dccdae5 CH	81	if (addr1 + vec1->bv_len != addr2)
6a9f5f24	82	return false;
0383ad43	83	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
6a9f5f24	84	return false;
3dccdae5 CH	85	if ((addr1 \| mask) != ((addr2 + vec2->bv_len - 1) \| mask))
3dccdae5 CH	86	return false;
6a9f5f24 CH	87	return true;
	88	}
	89
27ca1d4e CH	90	static inline bool __bvec_gap_to_prev(struct request_queue *q,
	91	struct bio_vec *bprv, unsigned int offset)
	92	{
df376b2e	93	return (offset & queue_virt_boundary(q)) \|\|
27ca1d4e CH	94	((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
	95	}
	96
	97	/*
	98	* Check if adding a bio_vec after bprv with offset would create a gap in
	99	* the SG list. Most drivers don't care about this, but some do.
	100	*/
	101	static inline bool bvec_gap_to_prev(struct request_queue *q,
	102	struct bio_vec *bprv, unsigned int offset)
	103	{
	104	if (!queue_virt_boundary(q))
	105	return false;
	106	return __bvec_gap_to_prev(q, bprv, offset);
	107	}
	108
1aa0a133 CH	109	static inline void blk_rq_bio_prep(struct request rq, struct bio bio,
	110	unsigned int nr_segs)
	111	{
	112	rq->nr_phys_segments = nr_segs;
	113	rq->__data_len = bio->bi_iter.bi_size;
	114	rq->bio = rq->biotail = bio;
	115	rq->ioprio = bio_prio(bio);
	116
	117	if (bio->bi_disk)
	118	rq->rq_disk = bio->bi_disk;
	119	}
	120
5a48fc14 DW	121	#ifdef CONFIG_BLK_DEV_INTEGRITY
5a48fc14 DW	122	void blk_flush_integrity(void);
7c20f116	123	bool __bio_integrity_endio(struct bio *);
ece841ab	124	void bio_integrity_free(struct bio *bio);
7c20f116 CH	125	static inline bool bio_integrity_endio(struct bio *bio)
	126	{
	127	if (bio_integrity(bio))
	128	return __bio_integrity_endio(bio);
	129	return true;
	130	}
43b729bf CH	131
	132	static inline bool integrity_req_gap_back_merge(struct request *req,
	133	struct bio *next)
	134	{
	135	struct bio_integrity_payload *bip = bio_integrity(req->bio);
	136	struct bio_integrity_payload *bip_next = bio_integrity(next);
	137
	138	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
	139	bip_next->bip_vec[0].bv_offset);
	140	}
	141
	142	static inline bool integrity_req_gap_front_merge(struct request *req,
	143	struct bio *bio)
	144	{
	145	struct bio_integrity_payload *bip = bio_integrity(bio);
	146	struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
	147
	148	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
	149	bip_next->bip_vec[0].bv_offset);
	150	}
	151	#else /* CONFIG_BLK_DEV_INTEGRITY */
	152	static inline bool integrity_req_gap_back_merge(struct request *req,
	153	struct bio *next)
	154	{
	155	return false;
	156	}
	157	static inline bool integrity_req_gap_front_merge(struct request *req,
	158	struct bio *bio)
	159	{
	160	return false;
	161	}
	162
5a48fc14 DW	163	static inline void blk_flush_integrity(void)
	164	{
	165	}
7c20f116 CH	166	static inline bool bio_integrity_endio(struct bio *bio)
	167	{
	168	return true;
	169	}
ece841ab JT	170	static inline void bio_integrity_free(struct bio *bio)
	171	{
	172	}
43b729bf	173	#endif /* CONFIG_BLK_DEV_INTEGRITY */
8324aa91	174
0d2602ca	175	unsigned long blk_rq_timeout(unsigned long timeout);
87ee7b11	176	void blk_add_timer(struct request *req);
320ae51f	177
14ccb66b CH	178	bool bio_attempt_front_merge(struct request req, struct bio bio,
	179	unsigned int nr_segs);
	180	bool bio_attempt_back_merge(struct request req, struct bio bio,
	181	unsigned int nr_segs);
1e739730 CH	182	bool bio_attempt_discard_merge(struct request_queue q, struct request req,
1e739730 CH	183	struct bio *bio);
320ae51f	184	bool blk_attempt_plug_merge(struct request_queue q, struct bio bio,
14ccb66b	185	unsigned int nr_segs, struct request **same_queue_rq);
320ae51f JA	186
	187	void blk_account_io_start(struct request *req, bool new_io);
	188	void blk_account_io_completion(struct request *req, unsigned int bytes);
522a7775	189	void blk_account_io_done(struct request *req, u64 now);
320ae51f	190
158dbda0 TH	191	/*
	192	* Internal elevator interface
	193	*/
e8064021	194	#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
158dbda0	195
ae1b1539	196	void blk_insert_flush(struct request *rq);
dd831006	197
954b4a5c	198	void elevator_init_mq(struct request_queue *q);
d48ece20 JW	199	int elevator_switch_mq(struct request_queue *q,
d48ece20 JW	200	struct elevator_type *new_e);
c3e22192	201	void __elevator_exit(struct request_queue , struct elevator_queue );
cecf5d87	202	int elv_register_queue(struct request_queue *q, bool uevent);
83d016ac BVA	203	void elv_unregister_queue(struct request_queue *q);
83d016ac BVA	204
c3e22192 ML	205	static inline void elevator_exit(struct request_queue *q,
	206	struct elevator_queue *e)
	207	{
284b94be ML	208	lockdep_assert_held(&q->sysfs_lock);
284b94be ML	209
c3e22192 ML	210	blk_mq_sched_free_requests(q);
	211	__elevator_exit(q, e);
	212	}
	213
807d4af2 CH	214	struct hd_struct __disk_get_part(struct gendisk disk, int partno);
807d4af2 CH	215
581d4e28 JA	216	#ifdef CONFIG_FAIL_IO_TIMEOUT
	217	int blk_should_fake_timeout(struct request_queue *);
	218	ssize_t part_timeout_show(struct device , struct device_attribute , char *);
	219	ssize_t part_timeout_store(struct device , struct device_attribute ,
	220	const char *, size_t);
	221	#else
	222	static inline int blk_should_fake_timeout(struct request_queue *q)
	223	{
	224	return 0;
	225	}
	226	#endif
	227
14ccb66b CH	228	void __blk_queue_split(struct request_queue q, struct bio *bio,
	229	unsigned int *nr_segs);
	230	int ll_back_merge_fn(struct request req, struct bio bio,
	231	unsigned int nr_segs);
	232	int ll_front_merge_fn(struct request req, struct bio bio,
	233	unsigned int nr_segs);
b973cb7e JA	234	struct request attempt_back_merge(struct request_queue q, struct request *rq);
b973cb7e JA	235	struct request attempt_front_merge(struct request_queue q, struct request *rq);
5e84ea3a JA	236	int blk_attempt_req_merge(struct request_queue q, struct request rq,
5e84ea3a JA	237	struct request *next);
e9cd19c0	238	unsigned int blk_recalc_rq_segments(struct request *rq);
80a761fd	239	void blk_rq_set_mixed_merge(struct request *rq);
050c8ea8	240	bool blk_rq_merge_ok(struct request rq, struct bio bio);
34fe7c05	241	enum elv_merge blk_try_merge(struct request rq, struct bio bio);
d6d48196	242
ff88972c AB	243	int blk_dev_init(void);
ff88972c AB	244
c2553b58 JA	245	/*
	246	* Contribute to IO statistics IFF:
	247	*
	248	* a) it's attached to a gendisk, and
48d9b0d4	249	* b) the queue had IO stats enabled when this request was started
c2553b58	250	*/
599d067d	251	static inline bool blk_do_io_stat(struct request *rq)
fb8ec18c	252	{
48d9b0d4	253	return rq->rq_disk && (rq->rq_flags & RQF_IO_STAT);
fb8ec18c JA	254	}
fb8ec18c JA	255
6cf7677f CH	256	static inline void req_set_nomerge(struct request_queue q, struct request req)
	257	{
	258	req->cmd_flags \|= REQ_NOMERGE;
	259	if (req == q->last_merge)
	260	q->last_merge = NULL;
	261	}
	262
1adfc5e4 ML	263	/*
	264	* The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
	265	* is defined as 'unsigned int', meantime it has to aligned to with logical
	266	* block size which is the minimum accepted unit by hardware.
	267	*/
	268	static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
	269	{
	270	return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
	271	}
	272
f2dbd76a TH	273	/*
	274	* Internal io_context interface
	275	*/
	276	void get_io_context(struct io_context *ioc);
47fdd4ca	277	struct io_cq ioc_lookup_icq(struct io_context ioc, struct request_queue *q);
24acfc34 TH	278	struct io_cq ioc_create_icq(struct io_context ioc, struct request_queue *q,
24acfc34 TH	279	gfp_t gfp_mask);
7e5a8794	280	void ioc_clear_queue(struct request_queue *q);
f2dbd76a	281
24acfc34	282	int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
f2dbd76a TH	283
	284	/**
	285	* create_io_context - try to create task->io_context
f2dbd76a TH	286	* @gfp_mask: allocation mask
	287	* @node: allocation node
	288	*
24acfc34 TH	289	* If %current->io_context is %NULL, allocate a new io_context and install
	290	* it. Returns the current %current->io_context which may be %NULL if
	291	* allocation failed.
f2dbd76a TH	292	*
f2dbd76a TH	293	* Note that this function can't be called with IRQ disabled because
24acfc34	294	* task_lock which protects %current->io_context is IRQ-unsafe.
f2dbd76a	295	*/
24acfc34	296	static inline struct io_context *create_io_context(gfp_t gfp_mask, int node)
f2dbd76a TH	297	{
f2dbd76a TH	298	WARN_ON_ONCE(irqs_disabled());
24acfc34 TH	299	if (unlikely(!current->io_context))
	300	create_task_io_context(current, gfp_mask, node);
	301	return current->io_context;
f2dbd76a TH	302	}
	303
	304	/*
	305	* Internal throttling interface
	306	*/
bc9fcbf9	307	#ifdef CONFIG_BLK_DEV_THROTTLING
c9a929dd	308	extern void blk_throtl_drain(struct request_queue *q);
bc9fcbf9 TH	309	extern int blk_throtl_init(struct request_queue *q);
bc9fcbf9 TH	310	extern void blk_throtl_exit(struct request_queue *q);
d61fcfa4	311	extern void blk_throtl_register_queue(struct request_queue *q);
bc9fcbf9	312	#else /* CONFIG_BLK_DEV_THROTTLING */
c9a929dd	313	static inline void blk_throtl_drain(struct request_queue *q) { }
bc9fcbf9 TH	314	static inline int blk_throtl_init(struct request_queue *q) { return 0; }
bc9fcbf9 TH	315	static inline void blk_throtl_exit(struct request_queue *q) { }
d61fcfa4	316	static inline void blk_throtl_register_queue(struct request_queue *q) { }
bc9fcbf9	317	#endif /* CONFIG_BLK_DEV_THROTTLING */
297e3d85 SL	318	#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
	319	extern ssize_t blk_throtl_sample_time_show(struct request_queue q, char page);
	320	extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
	321	const char *page, size_t count);
9e234eea	322	extern void blk_throtl_bio_endio(struct bio *bio);
b9147dd1	323	extern void blk_throtl_stat_add(struct request *rq, u64 time);
9e234eea SL	324	#else
9e234eea SL	325	static inline void blk_throtl_bio_endio(struct bio *bio) { }
b9147dd1	326	static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
297e3d85	327	#endif
bc9fcbf9	328
3bce016a CH	329	#ifdef CONFIG_BOUNCE
	330	extern int init_emergency_isa_pool(void);
	331	extern void blk_queue_bounce(struct request_queue q, struct bio *bio);
	332	#else
	333	static inline int init_emergency_isa_pool(void)
	334	{
	335	return 0;
	336	}
	337	static inline void blk_queue_bounce(struct request_queue q, struct bio *bio)
	338	{
	339	}
	340	#endif /* CONFIG_BOUNCE */
	341
d7067512 JB	342	#ifdef CONFIG_BLK_CGROUP_IOLATENCY
	343	extern int blk_iolatency_init(struct request_queue *q);
	344	#else
	345	static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
	346	#endif
	347
a2d6b3a2 DLM	348	struct bio blk_next_bio(struct bio bio, unsigned int nr_pages, gfp_t gfp);
a2d6b3a2 DLM	349
bf505456 DLM	350	#ifdef CONFIG_BLK_DEV_ZONED
	351	void blk_queue_free_zone_bitmaps(struct request_queue *q);
	352	#else
	353	static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
	354	#endif
	355
bc9fcbf9	356	#endif /* BLK_INTERNAL_H */