[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 <linux/part_stat.h>
#include <linux/blk-crypto.h>
#include <xen/xen.h>
#include "blk-crypto-internal.h"
#include "blk-mq.h"
#include "blk-mq-sched.h"

/* Max future timer expiry for timeouts */
#define BLK_MAX_TIMEOUT		(5 * HZ)

extern struct dentry *blk_debugfs_root;

struct blk_flush_queue {
	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;

	struct lock_class_key	key;
	spinlock_t		mq_flush_lock;
};

enum bio_merge_status {
	BIO_MERGE_OK,
	BIO_MERGE_NONE,
	BIO_MERGE_FAILED,
};

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(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 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;
}

bool blk_integrity_merge_rq(struct request_queue *, struct request *,
		struct request *);

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);
}

void blk_integrity_add(struct gendisk *);
void blk_integrity_del(struct gendisk *);
#else /* CONFIG_BLK_DEV_INTEGRITY */
static inline bool blk_integrity_merge_rq(struct request_queue *rq,
		struct request *r1, struct request *r2)
{
	return true;
}
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)
{
}
static inline void blk_integrity_add(struct gendisk *disk)
{
}
static inline void blk_integrity_del(struct gendisk *disk)
{
}
#endif /* CONFIG_BLK_DEV_INTEGRITY */

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

enum bio_merge_status bio_attempt_front_merge(struct request *req,
					      struct bio *bio,
					      unsigned int nr_segs);
enum bio_merge_status bio_attempt_back_merge(struct request *req,
					     struct bio *bio,
					     unsigned int nr_segs);
enum bio_merge_status 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);
bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
			struct bio *bio, unsigned int nr_segs);

void blk_account_io_start(struct request *req);
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);

ssize_t part_size_show(struct device *dev, struct device_attribute *attr,
		char *buf);
ssize_t part_stat_show(struct device *dev, struct device_attribute *attr,
		char *buf);
ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
		char *buf);
ssize_t part_fail_show(struct device *dev, struct device_attribute *attr,
		char *buf);
ssize_t part_fail_store(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count);
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);

void __blk_queue_split(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;
}

/*
 * The max bio size which is aligned to q->limits.discard_granularity. This
 * is a hint to split large discard bio in generic block layer, then if device
 * driver needs to split the discard bio into smaller ones, their bi_size can
 * be very probably and easily aligned to discard_granularity of the device's
 * queue.
 */
static inline unsigned int bio_aligned_discard_max_sectors(
					struct request_queue *q)
{
	return round_down(UINT_MAX, q->limits.discard_granularity) >>
			SECTOR_SHIFT;
}

/*
 * 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);

/*
 * Internal throttling interface
 */
#ifdef CONFIG_BLK_DEV_THROTTLING
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);
bool blk_throtl_bio(struct bio *bio);
#else /* CONFIG_BLK_DEV_THROTTLING */
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) { }
static inline bool blk_throtl_bio(struct bio *bio) { return false; }
#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

struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector);

int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
void blk_free_devt(dev_t devt);
void blk_invalidate_devt(dev_t devt);
char *disk_name(struct gendisk *hd, int partno, char *buf);
#define ADDPART_FLAG_NONE	0
#define ADDPART_FLAG_RAID	1
#define ADDPART_FLAG_WHOLEDISK	2
void delete_partition(struct hd_struct *part);
int bdev_add_partition(struct block_device *bdev, int partno,
		sector_t start, sector_t length);
int bdev_del_partition(struct block_device *bdev, int partno);
int bdev_resize_partition(struct block_device *bdev, int partno,
		sector_t start, sector_t length);
int disk_expand_part_tbl(struct gendisk *disk, int target);
int hd_ref_init(struct hd_struct *part);

/* no need to get/put refcount of part0 */
static inline int hd_struct_try_get(struct hd_struct *part)
{
	if (part->partno)
		return percpu_ref_tryget_live(&part->ref);
	return 1;
}

static inline void hd_struct_put(struct hd_struct *part)
{
	if (part->partno)
		percpu_ref_put(&part->ref);
}

static inline void hd_free_part(struct hd_struct *part)
{
	free_percpu(part->dkstats);
	kfree(part->info);
	percpu_ref_exit(&part->ref);
}

/*
 * Any access of part->nr_sects which is not protected by partition
 * bd_mutex or gendisk bdev bd_mutex, should be done using this
 * accessor function.
 *
 * Code written along the lines of i_size_read() and i_size_write().
 * CONFIG_PREEMPTION case optimizes the case of UP kernel with preemption
 * on.
 */
static inline sector_t part_nr_sects_read(struct hd_struct *part)
{
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
	sector_t nr_sects;
	unsigned seq;
	do {
		seq = read_seqcount_begin(&part->nr_sects_seq);
		nr_sects = part->nr_sects;
	} while (read_seqcount_retry(&part->nr_sects_seq, seq));
	return nr_sects;
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
	sector_t nr_sects;

	preempt_disable();
	nr_sects = part->nr_sects;
	preempt_enable();
	return nr_sects;
#else
	return part->nr_sects;
#endif
}

/*
 * Should be called with mutex lock held (typically bd_mutex) of partition
 * to provide mutual exlusion among writers otherwise seqcount might be
 * left in wrong state leaving the readers spinning infinitely.
 */
static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
{
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
	preempt_disable();
	write_seqcount_begin(&part->nr_sects_seq);
	part->nr_sects = size;
	write_seqcount_end(&part->nr_sects_seq);
	preempt_enable();
#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
	preempt_disable();
	part->nr_sects = size;
	preempt_enable();
#else
	part->nr_sects = size;
#endif
}

int bio_add_hw_page(struct request_queue *q, struct bio *bio,
		struct page *page, unsigned int len, unsigned int offset,
		unsigned int max_sectors, bool *same_page);

#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>
c6a564ff	7	#include <linux/part_stat.h>
a892c8d5	8	#include <linux/blk-crypto.h>
c39ae60d	9	#include <xen/xen.h>
a892c8d5	10	#include "blk-crypto-internal.h"
f70ced09	11	#include "blk-mq.h"
c3e22192	12	#include "blk-mq-sched.h"
a73f730d	13
0d2602ca JA	14	/* Max future timer expiry for timeouts */
	15	#define BLK_MAX_TIMEOUT (5 * HZ)
	16
18fbda91	17	extern struct dentry *blk_debugfs_root;
18fbda91	18
7c94e1c1	19	struct blk_flush_queue {
7c94e1c1 ML	20	unsigned int flush_pending_idx:1;
7c94e1c1 ML	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	27
b3c6a599	28	struct lock_class_key key;
7c94e1c1 ML	29	spinlock_t mq_flush_lock;
	30	};
	31
7d7ca7c5 BW	32	enum bio_merge_status {
	33	BIO_MERGE_OK,
	34	BIO_MERGE_NONE,
	35	BIO_MERGE_FAILED,
	36	};
	37
8324aa91 JA	38	extern struct kmem_cache *blk_requestq_cachep;
8324aa91 JA	39	extern struct kobj_type blk_queue_ktype;
a73f730d	40	extern struct ida blk_queue_ida;
8324aa91	41
f9afca4d JA	42	static inline struct blk_flush_queue *
f9afca4d JA	43	blk_get_flush_queue(struct request_queue q, struct blk_mq_ctx ctx)
7c94e1c1	44	{
8ccdf4a3	45	return blk_mq_map_queue(q, REQ_OP_FLUSH, ctx)->fq;
7c94e1c1 ML	46	}
7c94e1c1 ML	47
09ac46c4 TH	48	static inline void __blk_get_queue(struct request_queue *q)
	49	{
	50	kobject_get(&q->kobj);
	51	}
	52
8d699663 YY	53	static inline bool
	54	is_flush_rq(struct request req, struct blk_mq_hw_ctx hctx)
	55	{
	56	return hctx->fq->flush_rq == req;
	57	}
	58
754a1572 GJ	59	struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size,
754a1572 GJ	60	gfp_t flags);
f70ced09	61	void blk_free_flush_queue(struct blk_flush_queue *q);
f3552655	62
3ef28e83 DW	63	void blk_freeze_queue(struct request_queue *q);
3ef28e83 DW	64
3dccdae5 CH	65	static inline bool biovec_phys_mergeable(struct request_queue *q,
3dccdae5 CH	66	struct bio_vec vec1, struct bio_vec vec2)
6a9f5f24	67	{
3dccdae5	68	unsigned long mask = queue_segment_boundary(q);
6e768461 CH	69	phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
6e768461 CH	70	phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
3dccdae5 CH	71
3dccdae5 CH	72	if (addr1 + vec1->bv_len != addr2)
6a9f5f24	73	return false;
0383ad43	74	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
6a9f5f24	75	return false;
3dccdae5 CH	76	if ((addr1 \| mask) != ((addr2 + vec2->bv_len - 1) \| mask))
3dccdae5 CH	77	return false;
6a9f5f24 CH	78	return true;
	79	}
	80
27ca1d4e CH	81	static inline bool __bvec_gap_to_prev(struct request_queue *q,
	82	struct bio_vec *bprv, unsigned int offset)
	83	{
df376b2e	84	return (offset & queue_virt_boundary(q)) \|\|
27ca1d4e CH	85	((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
	86	}
	87
	88	/*
	89	* Check if adding a bio_vec after bprv with offset would create a gap in
	90	* the SG list. Most drivers don't care about this, but some do.
	91	*/
	92	static inline bool bvec_gap_to_prev(struct request_queue *q,
	93	struct bio_vec *bprv, unsigned int offset)
	94	{
	95	if (!queue_virt_boundary(q))
	96	return false;
	97	return __bvec_gap_to_prev(q, bprv, offset);
	98	}
	99
1aa0a133 CH	100	static inline void blk_rq_bio_prep(struct request rq, struct bio bio,
	101	unsigned int nr_segs)
	102	{
	103	rq->nr_phys_segments = nr_segs;
	104	rq->__data_len = bio->bi_iter.bi_size;
	105	rq->bio = rq->biotail = bio;
	106	rq->ioprio = bio_prio(bio);
	107
	108	if (bio->bi_disk)
	109	rq->rq_disk = bio->bi_disk;
	110	}
	111
5a48fc14 DW	112	#ifdef CONFIG_BLK_DEV_INTEGRITY
5a48fc14 DW	113	void blk_flush_integrity(void);
7c20f116	114	bool __bio_integrity_endio(struct bio *);
ece841ab	115	void bio_integrity_free(struct bio *bio);
7c20f116 CH	116	static inline bool bio_integrity_endio(struct bio *bio)
	117	{
	118	if (bio_integrity(bio))
	119	return __bio_integrity_endio(bio);
	120	return true;
	121	}
43b729bf	122
92cf2fd1 CH	123	bool blk_integrity_merge_rq(struct request_queue , struct request ,
	124	struct request *);
	125
43b729bf CH	126	static inline bool integrity_req_gap_back_merge(struct request *req,
	127	struct bio *next)
	128	{
	129	struct bio_integrity_payload *bip = bio_integrity(req->bio);
	130	struct bio_integrity_payload *bip_next = bio_integrity(next);
	131
	132	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
	133	bip_next->bip_vec[0].bv_offset);
	134	}
	135
	136	static inline bool integrity_req_gap_front_merge(struct request *req,
	137	struct bio *bio)
	138	{
	139	struct bio_integrity_payload *bip = bio_integrity(bio);
	140	struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
	141
	142	return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
	143	bip_next->bip_vec[0].bv_offset);
	144	}
581e2600 CH	145
	146	void blk_integrity_add(struct gendisk *);
	147	void blk_integrity_del(struct gendisk *);
43b729bf	148	#else /* CONFIG_BLK_DEV_INTEGRITY */
92cf2fd1 CH	149	static inline bool blk_integrity_merge_rq(struct request_queue *rq,
	150	struct request r1, struct request r2)
	151	{
	152	return true;
	153	}
43b729bf CH	154	static inline bool integrity_req_gap_back_merge(struct request *req,
	155	struct bio *next)
	156	{
	157	return false;
	158	}
	159	static inline bool integrity_req_gap_front_merge(struct request *req,
	160	struct bio *bio)
	161	{
	162	return false;
	163	}
	164
5a48fc14 DW	165	static inline void blk_flush_integrity(void)
	166	{
	167	}
7c20f116 CH	168	static inline bool bio_integrity_endio(struct bio *bio)
	169	{
	170	return true;
	171	}
ece841ab JT	172	static inline void bio_integrity_free(struct bio *bio)
	173	{
	174	}
581e2600 CH	175	static inline void blk_integrity_add(struct gendisk *disk)
	176	{
	177	}
	178	static inline void blk_integrity_del(struct gendisk *disk)
	179	{
	180	}
43b729bf	181	#endif /* CONFIG_BLK_DEV_INTEGRITY */
8324aa91	182
0d2602ca	183	unsigned long blk_rq_timeout(unsigned long timeout);
87ee7b11	184	void blk_add_timer(struct request *req);
320ae51f	185
7d7ca7c5 BW	186	enum bio_merge_status bio_attempt_front_merge(struct request *req,
	187	struct bio *bio,
	188	unsigned int nr_segs);
	189	enum bio_merge_status bio_attempt_back_merge(struct request *req,
	190	struct bio *bio,
	191	unsigned int nr_segs);
	192	enum bio_merge_status bio_attempt_discard_merge(struct request_queue *q,
	193	struct request *req,
	194	struct bio *bio);
320ae51f	195	bool blk_attempt_plug_merge(struct request_queue q, struct bio bio,
14ccb66b	196	unsigned int nr_segs, struct request **same_queue_rq);
bdc6a287 BW	197	bool blk_bio_list_merge(struct request_queue q, struct list_head list,
bdc6a287 BW	198	struct bio *bio, unsigned int nr_segs);
320ae51f	199
b5af37ab	200	void blk_account_io_start(struct request *req);
522a7775	201	void blk_account_io_done(struct request *req, u64 now);
320ae51f	202
158dbda0 TH	203	/*
	204	* Internal elevator interface
	205	*/
e8064021	206	#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
158dbda0	207
ae1b1539	208	void blk_insert_flush(struct request *rq);
dd831006	209
954b4a5c	210	void elevator_init_mq(struct request_queue *q);
d48ece20 JW	211	int elevator_switch_mq(struct request_queue *q,
d48ece20 JW	212	struct elevator_type *new_e);
c3e22192	213	void __elevator_exit(struct request_queue , struct elevator_queue );
cecf5d87	214	int elv_register_queue(struct request_queue *q, bool uevent);
83d016ac BVA	215	void elv_unregister_queue(struct request_queue *q);
83d016ac BVA	216
c3e22192 ML	217	static inline void elevator_exit(struct request_queue *q,
	218	struct elevator_queue *e)
	219	{
284b94be ML	220	lockdep_assert_held(&q->sysfs_lock);
284b94be ML	221
c3e22192 ML	222	blk_mq_sched_free_requests(q);
	223	__elevator_exit(q, e);
	224	}
	225
807d4af2 CH	226	struct hd_struct __disk_get_part(struct gendisk disk, int partno);
807d4af2 CH	227
3ad5cee5 CH	228	ssize_t part_size_show(struct device dev, struct device_attribute attr,
	229	char *buf);
	230	ssize_t part_stat_show(struct device dev, struct device_attribute attr,
	231	char *buf);
	232	ssize_t part_inflight_show(struct device dev, struct device_attribute attr,
	233	char *buf);
	234	ssize_t part_fail_show(struct device dev, struct device_attribute attr,
	235	char *buf);
	236	ssize_t part_fail_store(struct device dev, struct device_attribute attr,
	237	const char *buf, size_t count);
581d4e28 JA	238	ssize_t part_timeout_show(struct device , struct device_attribute , char *);
	239	ssize_t part_timeout_store(struct device , struct device_attribute ,
	240	const char *, size_t);
581d4e28	241
f695ca38	242	void __blk_queue_split(struct bio *bio, unsigned int nr_segs);
14ccb66b CH	243	int ll_back_merge_fn(struct request req, struct bio bio,
	244	unsigned int nr_segs);
	245	int ll_front_merge_fn(struct request req, struct bio bio,
	246	unsigned int nr_segs);
b973cb7e JA	247	struct request attempt_back_merge(struct request_queue q, struct request *rq);
b973cb7e JA	248	struct request attempt_front_merge(struct request_queue q, struct request *rq);
5e84ea3a JA	249	int blk_attempt_req_merge(struct request_queue q, struct request rq,
5e84ea3a JA	250	struct request *next);
e9cd19c0	251	unsigned int blk_recalc_rq_segments(struct request *rq);
80a761fd	252	void blk_rq_set_mixed_merge(struct request *rq);
050c8ea8	253	bool blk_rq_merge_ok(struct request rq, struct bio bio);
34fe7c05	254	enum elv_merge blk_try_merge(struct request rq, struct bio bio);
d6d48196	255
ff88972c AB	256	int blk_dev_init(void);
ff88972c AB	257
c2553b58 JA	258	/*
	259	* Contribute to IO statistics IFF:
	260	*
	261	* a) it's attached to a gendisk, and
48d9b0d4	262	* b) the queue had IO stats enabled when this request was started
c2553b58	263	*/
599d067d	264	static inline bool blk_do_io_stat(struct request *rq)
fb8ec18c	265	{
48d9b0d4	266	return rq->rq_disk && (rq->rq_flags & RQF_IO_STAT);
fb8ec18c JA	267	}
fb8ec18c JA	268
6cf7677f CH	269	static inline void req_set_nomerge(struct request_queue q, struct request req)
	270	{
	271	req->cmd_flags \|= REQ_NOMERGE;
	272	if (req == q->last_merge)
	273	q->last_merge = NULL;
	274	}
	275
1adfc5e4 ML	276	/*
	277	* The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size
	278	* is defined as 'unsigned int', meantime it has to aligned to with logical
	279	* block size which is the minimum accepted unit by hardware.
	280	*/
	281	static inline unsigned int bio_allowed_max_sectors(struct request_queue *q)
	282	{
	283	return round_down(UINT_MAX, queue_logical_block_size(q)) >> 9;
	284	}
	285
9b15d109 CL	286	/*
	287	* The max bio size which is aligned to q->limits.discard_granularity. This
	288	* is a hint to split large discard bio in generic block layer, then if device
	289	* driver needs to split the discard bio into smaller ones, their bi_size can
	290	* be very probably and easily aligned to discard_granularity of the device's
	291	* queue.
	292	*/
	293	static inline unsigned int bio_aligned_discard_max_sectors(
	294	struct request_queue *q)
	295	{
	296	return round_down(UINT_MAX, q->limits.discard_granularity) >>
	297	SECTOR_SHIFT;
	298	}
	299
f2dbd76a TH	300	/*
	301	* Internal io_context interface
	302	*/
	303	void get_io_context(struct io_context *ioc);
47fdd4ca	304	struct io_cq ioc_lookup_icq(struct io_context ioc, struct request_queue *q);
24acfc34 TH	305	struct io_cq ioc_create_icq(struct io_context ioc, struct request_queue *q,
24acfc34 TH	306	gfp_t gfp_mask);
7e5a8794	307	void ioc_clear_queue(struct request_queue *q);
f2dbd76a	308
24acfc34	309	int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
f2dbd76a	310
f2dbd76a TH	311	/*
	312	* Internal throttling interface
	313	*/
bc9fcbf9	314	#ifdef CONFIG_BLK_DEV_THROTTLING
bc9fcbf9 TH	315	extern int blk_throtl_init(struct request_queue *q);
bc9fcbf9 TH	316	extern void blk_throtl_exit(struct request_queue *q);
d61fcfa4	317	extern void blk_throtl_register_queue(struct request_queue *q);
db18a53e	318	bool blk_throtl_bio(struct bio *bio);
bc9fcbf9	319	#else /* CONFIG_BLK_DEV_THROTTLING */
bc9fcbf9 TH	320	static inline int blk_throtl_init(struct request_queue *q) { return 0; }
bc9fcbf9 TH	321	static inline void blk_throtl_exit(struct request_queue *q) { }
d61fcfa4	322	static inline void blk_throtl_register_queue(struct request_queue *q) { }
db18a53e	323	static inline bool blk_throtl_bio(struct bio *bio) { return false; }
bc9fcbf9	324	#endif /* CONFIG_BLK_DEV_THROTTLING */
297e3d85 SL	325	#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
	326	extern ssize_t blk_throtl_sample_time_show(struct request_queue q, char page);
	327	extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
	328	const char *page, size_t count);
9e234eea	329	extern void blk_throtl_bio_endio(struct bio *bio);
b9147dd1	330	extern void blk_throtl_stat_add(struct request *rq, u64 time);
9e234eea SL	331	#else
9e234eea SL	332	static inline void blk_throtl_bio_endio(struct bio *bio) { }
b9147dd1	333	static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
297e3d85	334	#endif
bc9fcbf9	335
3bce016a CH	336	#ifdef CONFIG_BOUNCE
	337	extern int init_emergency_isa_pool(void);
	338	extern void blk_queue_bounce(struct request_queue q, struct bio *bio);
	339	#else
	340	static inline int init_emergency_isa_pool(void)
	341	{
	342	return 0;
	343	}
	344	static inline void blk_queue_bounce(struct request_queue q, struct bio *bio)
	345	{
	346	}
	347	#endif /* CONFIG_BOUNCE */
	348
d7067512 JB	349	#ifdef CONFIG_BLK_CGROUP_IOLATENCY
	350	extern int blk_iolatency_init(struct request_queue *q);
	351	#else
	352	static inline int blk_iolatency_init(struct request_queue *q) { return 0; }
	353	#endif
	354
a2d6b3a2 DLM	355	struct bio blk_next_bio(struct bio bio, unsigned int nr_pages, gfp_t gfp);
a2d6b3a2 DLM	356
bf505456 DLM	357	#ifdef CONFIG_BLK_DEV_ZONED
	358	void blk_queue_free_zone_bitmaps(struct request_queue *q);
	359	#else
	360	static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
	361	#endif
	362
581e2600 CH	363	struct hd_struct disk_map_sector_rcu(struct gendisk disk, sector_t sector);
	364
	365	int blk_alloc_devt(struct hd_struct part, dev_t devt);
	366	void blk_free_devt(dev_t devt);
	367	void blk_invalidate_devt(dev_t devt);
	368	char disk_name(struct gendisk hd, int partno, char *buf);
	369	#define ADDPART_FLAG_NONE 0
	370	#define ADDPART_FLAG_RAID 1
	371	#define ADDPART_FLAG_WHOLEDISK 2
8328eb28	372	void delete_partition(struct hd_struct *part);
fa9156ae CH	373	int bdev_add_partition(struct block_device *bdev, int partno,
	374	sector_t start, sector_t length);
	375	int bdev_del_partition(struct block_device *bdev, int partno);
	376	int bdev_resize_partition(struct block_device *bdev, int partno,
	377	sector_t start, sector_t length);
581e2600	378	int disk_expand_part_tbl(struct gendisk *disk, int target);
8da2892e	379	int hd_ref_init(struct hd_struct *part);
581e2600	380
27eb3af9	381	/* no need to get/put refcount of part0 */
581e2600 CH	382	static inline int hd_struct_try_get(struct hd_struct *part)
581e2600 CH	383	{
27eb3af9 ML	384	if (part->partno)
	385	return percpu_ref_tryget_live(&part->ref);
	386	return 1;
581e2600 CH	387	}
	388
	389	static inline void hd_struct_put(struct hd_struct *part)
	390	{
27eb3af9 ML	391	if (part->partno)
27eb3af9 ML	392	percpu_ref_put(&part->ref);
581e2600 CH	393	}
581e2600 CH	394
581e2600 CH	395	static inline void hd_free_part(struct hd_struct *part)
581e2600 CH	396	{
58d4f14f	397	free_percpu(part->dkstats);
581e2600 CH	398	kfree(part->info);
	399	percpu_ref_exit(&part->ref);
	400	}
	401
	402	/*
	403	* Any access of part->nr_sects which is not protected by partition
	404	* bd_mutex or gendisk bdev bd_mutex, should be done using this
	405	* accessor function.
	406	*
	407	* Code written along the lines of i_size_read() and i_size_write().
	408	* CONFIG_PREEMPTION case optimizes the case of UP kernel with preemption
	409	* on.
	410	*/
	411	static inline sector_t part_nr_sects_read(struct hd_struct *part)
	412	{
	413	#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
	414	sector_t nr_sects;
	415	unsigned seq;
	416	do {
	417	seq = read_seqcount_begin(&part->nr_sects_seq);
	418	nr_sects = part->nr_sects;
	419	} while (read_seqcount_retry(&part->nr_sects_seq, seq));
	420	return nr_sects;
	421	#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
	422	sector_t nr_sects;
	423
	424	preempt_disable();
	425	nr_sects = part->nr_sects;
	426	preempt_enable();
	427	return nr_sects;
	428	#else
	429	return part->nr_sects;
	430	#endif
	431	}
	432
	433	/*
	434	* Should be called with mutex lock held (typically bd_mutex) of partition
	435	* to provide mutual exlusion among writers otherwise seqcount might be
	436	* left in wrong state leaving the readers spinning infinitely.
	437	*/
	438	static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
	439	{
	440	#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
15b81ce5	441	preempt_disable();
581e2600 CH	442	write_seqcount_begin(&part->nr_sects_seq);
	443	part->nr_sects = size;
	444	write_seqcount_end(&part->nr_sects_seq);
15b81ce5	445	preempt_enable();
581e2600 CH	446	#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
	447	preempt_disable();
	448	part->nr_sects = size;
	449	preempt_enable();
	450	#else
	451	part->nr_sects = size;
	452	#endif
	453	}
	454
e4581105	455	int bio_add_hw_page(struct request_queue q, struct bio bio,
130879f1	456	struct page *page, unsigned int len, unsigned int offset,
e4581105	457	unsigned int max_sectors, bool *same_page);
130879f1	458
bc9fcbf9	459	#endif /* BLK_INTERNAL_H */