[linux-block.git] / block / blk.h

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

#include <linux/blk-crypto.h>
#include <linux/memblock.h>	/* for max_pfn/max_low_pfn */
#include <xen/xen.h>
#include "blk-crypto-internal.h"

struct elevator_type;

/* 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;

	spinlock_t		mq_flush_lock;
};

bool is_flush_rq(struct request *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);
void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic);
void blk_queue_start_drain(struct request_queue *q);
int __bio_queue_enter(struct request_queue *q, struct bio *bio);
void submit_bio_noacct_nocheck(struct bio *bio);

static inline bool blk_try_enter_queue(struct request_queue *q, bool pm)
{
	rcu_read_lock();
	if (!percpu_ref_tryget_live_rcu(&q->q_usage_counter))
		goto fail;

	/*
	 * The code that increments the pm_only counter must ensure that the
	 * counter is globally visible before the queue is unfrozen.
	 */
	if (blk_queue_pm_only(q) &&
	    (!pm || queue_rpm_status(q) == RPM_SUSPENDED))
		goto fail_put;

	rcu_read_unlock();
	return true;

fail_put:
	blk_queue_exit(q);
fail:
	rcu_read_unlock();
	return false;
}

static inline int bio_queue_enter(struct bio *bio)
{
	struct request_queue *q = bdev_get_queue(bio->bi_bdev);

	if (blk_try_enter_queue(q, false))
		return 0;
	return __bio_queue_enter(q, bio);
}

#define BIO_INLINE_VECS 4
struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs,
		gfp_t gfp_mask);
void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs);

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;

	/*
	 * Merging adjacent physical pages may not work correctly under KMSAN
	 * if their metadata pages aren't adjacent. Just disable merging.
	 */
	if (IS_ENABLED(CONFIG_KMSAN))
		return false;

	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(const struct queue_limits *lim,
		struct bio_vec *bprv, unsigned int offset)
{
	return (offset & lim->virt_boundary_mask) ||
		((bprv->bv_offset + bprv->bv_len) & lim->virt_boundary_mask);
}

/*
 * 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(const struct queue_limits *lim,
		struct bio_vec *bprv, unsigned int offset)
{
	if (!lim->virt_boundary_mask)
		return false;
	return __bvec_gap_to_prev(lim, bprv, offset);
}

static inline bool rq_mergeable(struct request *rq)
{
	if (blk_rq_is_passthrough(rq))
		return false;

	if (req_op(rq) == REQ_OP_FLUSH)
		return false;

	if (req_op(rq) == REQ_OP_WRITE_ZEROES)
		return false;

	if (req_op(rq) == REQ_OP_ZONE_APPEND)
		return false;

	if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
		return false;
	if (rq->rq_flags & RQF_NOMERGE_FLAGS)
		return false;

	return true;
}

/*
 * There are two different ways to handle DISCARD merges:
 *  1) If max_discard_segments > 1, the driver treats every bio as a range and
 *     send the bios to controller together. The ranges don't need to be
 *     contiguous.
 *  2) Otherwise, the request will be normal read/write requests.  The ranges
 *     need to be contiguous.
 */
static inline bool blk_discard_mergable(struct request *req)
{
	if (req_op(req) == REQ_OP_DISCARD &&
	    queue_max_discard_segments(req->q) > 1)
		return true;
	return false;
}

static inline unsigned int blk_rq_get_max_segments(struct request *rq)
{
	if (req_op(rq) == REQ_OP_DISCARD)
		return queue_max_discard_segments(rq->q);
	return queue_max_segments(rq->q);
}

static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
						     enum req_op op)
{
	if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
		return min(q->limits.max_discard_sectors,
			   UINT_MAX >> SECTOR_SHIFT);

	if (unlikely(op == REQ_OP_WRITE_ZEROES))
		return q->limits.max_write_zeroes_sectors;

	return q->limits.max_sectors;
}

#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 *);
bool blk_integrity_merge_bio(struct request_queue *, struct request *,
		struct bio *);

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->limits,
				&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->limits,
				&bip->bip_vec[bip->bip_vcnt - 1],
				bip_next->bip_vec[0].bv_offset);
}

int blk_integrity_add(struct gendisk *disk);
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 blk_integrity_merge_bio(struct request_queue *rq,
		struct request *r, struct bio *b)
{
	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 int blk_integrity_add(struct gendisk *disk)
{
	return 0;
}
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);
const char *blk_status_to_str(blk_status_t status);

bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
		unsigned int nr_segs);
bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
			struct bio *bio, unsigned int nr_segs);

/*
 * Plug flush limits
 */
#define BLK_MAX_REQUEST_COUNT	32
#define BLK_PLUG_FLUSH_SIZE	(128 * 1024)

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

void blk_insert_flush(struct request *rq);

int elevator_switch(struct request_queue *q, struct elevator_type *new_e);
void elevator_disable(struct request_queue *q);
void elevator_exit(struct request_queue *q);
int elv_register_queue(struct request_queue *q, bool uevent);
void elv_unregister_queue(struct request_queue *q);

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);

static inline bool bio_may_exceed_limits(struct bio *bio,
					 const struct queue_limits *lim)
{
	switch (bio_op(bio)) {
	case REQ_OP_DISCARD:
	case REQ_OP_SECURE_ERASE:
	case REQ_OP_WRITE_ZEROES:
		return true; /* non-trivial splitting decisions */
	default:
		break;
	}

	/*
	 * All drivers must accept single-segments bios that are <= PAGE_SIZE.
	 * This is a quick and dirty check that relies on the fact that
	 * bi_io_vec[0] is always valid if a bio has data.  The check might
	 * lead to occasional false negatives when bios are cloned, but compared
	 * to the performance impact of cloned bios themselves the loop below
	 * doesn't matter anyway.
	 */
	return lim->chunk_sectors || bio->bi_vcnt != 1 ||
		bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;
}

struct bio *__bio_split_to_limits(struct bio *bio,
				  const struct queue_limits *lim,
				  unsigned int *nr_segs);
int ll_back_merge_fn(struct request *req, struct bio *bio,
		unsigned int nr_segs);
bool 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);

void blk_set_default_limits(struct queue_limits *lim);
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_flags & RQF_IO_STAT) && !blk_rq_is_passthrough(rq);
}

void update_io_ticks(struct block_device *part, unsigned long now, bool end);

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;
}

/*
 * Internal io_context interface
 */
struct io_cq *ioc_find_get_icq(struct request_queue *q);
struct io_cq *ioc_lookup_icq(struct request_queue *q);
#ifdef CONFIG_BLK_ICQ
void ioc_clear_queue(struct request_queue *q);
#else
static inline void ioc_clear_queue(struct request_queue *q)
{
}
#endif /* CONFIG_BLK_ICQ */

#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

struct bio *__blk_queue_bounce(struct bio *bio, struct request_queue *q);

static inline bool blk_queue_may_bounce(struct request_queue *q)
{
	return IS_ENABLED(CONFIG_BOUNCE) &&
		q->limits.bounce == BLK_BOUNCE_HIGH &&
		max_low_pfn >= max_pfn;
}

static inline struct bio *blk_queue_bounce(struct bio *bio,
		struct request_queue *q)
{
	if (unlikely(blk_queue_may_bounce(q) && bio_has_data(bio)))
		return __blk_queue_bounce(bio, q);
	return bio;
}

#ifdef CONFIG_BLK_DEV_ZONED
void disk_free_zone_bitmaps(struct gendisk *disk);
void disk_clear_zone_settings(struct gendisk *disk);
#else
static inline void disk_free_zone_bitmaps(struct gendisk *disk) {}
static inline void disk_clear_zone_settings(struct gendisk *disk) {}
#endif

int blk_alloc_ext_minor(void);
void blk_free_ext_minor(unsigned int minor);
#define ADDPART_FLAG_NONE	0
#define ADDPART_FLAG_RAID	1
#define ADDPART_FLAG_WHOLEDISK	2
int bdev_add_partition(struct gendisk *disk, int partno, sector_t start,
		sector_t length);
int bdev_del_partition(struct gendisk *disk, int partno);
int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start,
		sector_t length);
void blk_drop_partitions(struct gendisk *disk);

struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
		struct lock_class_key *lkclass);

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);

struct request_queue *blk_alloc_queue(int node_id);

int disk_scan_partitions(struct gendisk *disk, fmode_t mode);

int disk_alloc_events(struct gendisk *disk);
void disk_add_events(struct gendisk *disk);
void disk_del_events(struct gendisk *disk);
void disk_release_events(struct gendisk *disk);
void disk_block_events(struct gendisk *disk);
void disk_unblock_events(struct gendisk *disk);
void disk_flush_events(struct gendisk *disk, unsigned int mask);
extern struct device_attribute dev_attr_events;
extern struct device_attribute dev_attr_events_async;
extern struct device_attribute dev_attr_events_poll_msecs;

extern struct attribute_group blk_trace_attr_group;

long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);

extern const struct address_space_operations def_blk_aops;

int disk_register_independent_access_ranges(struct gendisk *disk);
void disk_unregister_independent_access_ranges(struct gendisk *disk);

#ifdef CONFIG_FAIL_MAKE_REQUEST
bool should_fail_request(struct block_device *part, unsigned int bytes);
#else /* CONFIG_FAIL_MAKE_REQUEST */
static inline bool should_fail_request(struct block_device *part,
					unsigned int bytes)
{
	return false;
}
#endif /* CONFIG_FAIL_MAKE_REQUEST */

/*
 * Optimized request reference counting. Ideally we'd make timeouts be more
 * clever, as that's the only reason we need references at all... But until
 * this happens, this is faster than using refcount_t. Also see:
 *
 * abc54d634334 ("io_uring: switch to atomic_t for io_kiocb reference count")
 */
#define req_ref_zero_or_close_to_overflow(req)	\
	((unsigned int) atomic_read(&(req->ref)) + 127u <= 127u)

static inline bool req_ref_inc_not_zero(struct request *req)
{
	return atomic_inc_not_zero(&req->ref);
}

static inline bool req_ref_put_and_test(struct request *req)
{
	WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
	return atomic_dec_and_test(&req->ref);
}

static inline void req_ref_set(struct request *req, int value)
{
	atomic_set(&req->ref, value);
}

static inline int req_ref_read(struct request *req)
{
	return atomic_read(&req->ref);
}

#endif /* BLK_INTERNAL_H */
Commit	Line	Data
	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef BLK_INTERNAL_H
	3	#define BLK_INTERNAL_H
	4
	5	#include <linux/blk-crypto.h>
	6	#include <linux/memblock.h> /* for max_pfn/max_low_pfn */
	7	#include <xen/xen.h>
	8	#include "blk-crypto-internal.h"
	9
	10	struct elevator_type;
	11
	12	/* Max future timer expiry for timeouts */
	13	#define BLK_MAX_TIMEOUT (5 * HZ)
	14
	15	extern struct dentry *blk_debugfs_root;
	16
	17	struct blk_flush_queue {
	18	unsigned int flush_pending_idx:1;
	19	unsigned int flush_running_idx:1;
	20	blk_status_t rq_status;
	21	unsigned long flush_pending_since;
	22	struct list_head flush_queue[2];
	23	struct list_head flush_data_in_flight;
	24	struct request *flush_rq;
	25
	26	spinlock_t mq_flush_lock;
	27	};
	28
	29	bool is_flush_rq(struct request *req);
	30
	31	struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size,
	32	gfp_t flags);
	33	void blk_free_flush_queue(struct blk_flush_queue *q);
	34
	35	void blk_freeze_queue(struct request_queue *q);
	36	void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic);
	37	void blk_queue_start_drain(struct request_queue *q);
	38	int __bio_queue_enter(struct request_queue q, struct bio bio);
	39	void submit_bio_noacct_nocheck(struct bio *bio);
	40
	41	static inline bool blk_try_enter_queue(struct request_queue *q, bool pm)
	42	{
	43	rcu_read_lock();
	44	if (!percpu_ref_tryget_live_rcu(&q->q_usage_counter))
	45	goto fail;
	46
	47	/*
	48	* The code that increments the pm_only counter must ensure that the
	49	* counter is globally visible before the queue is unfrozen.
	50	*/
	51	if (blk_queue_pm_only(q) &&
	52	(!pm \|\| queue_rpm_status(q) == RPM_SUSPENDED))
	53	goto fail_put;
	54
	55	rcu_read_unlock();
	56	return true;
	57
	58	fail_put:
	59	blk_queue_exit(q);
	60	fail:
	61	rcu_read_unlock();
	62	return false;
	63	}
	64
	65	static inline int bio_queue_enter(struct bio *bio)
	66	{
	67	struct request_queue *q = bdev_get_queue(bio->bi_bdev);
	68
	69	if (blk_try_enter_queue(q, false))
	70	return 0;
	71	return __bio_queue_enter(q, bio);
	72	}
	73
	74	#define BIO_INLINE_VECS 4
	75	struct bio_vec bvec_alloc(mempool_t pool, unsigned short *nr_vecs,
	76	gfp_t gfp_mask);
	77	void bvec_free(mempool_t pool, struct bio_vec bv, unsigned short nr_vecs);
	78
	79	static inline bool biovec_phys_mergeable(struct request_queue *q,
	80	struct bio_vec vec1, struct bio_vec vec2)
	81	{
	82	unsigned long mask = queue_segment_boundary(q);
	83	phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset;
	84	phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset;
	85
	86	/*
	87	* Merging adjacent physical pages may not work correctly under KMSAN
	88	* if their metadata pages aren't adjacent. Just disable merging.
	89	*/
	90	if (IS_ENABLED(CONFIG_KMSAN))
	91	return false;
	92
	93	if (addr1 + vec1->bv_len != addr2)
	94	return false;
	95	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
	96	return false;
	97	if ((addr1 \| mask) != ((addr2 + vec2->bv_len - 1) \| mask))
	98	return false;
	99	return true;
	100	}
	101
	102	static inline bool __bvec_gap_to_prev(const struct queue_limits *lim,
	103	struct bio_vec *bprv, unsigned int offset)
	104	{
	105	return (offset & lim->virt_boundary_mask) \|\|
	106	((bprv->bv_offset + bprv->bv_len) & lim->virt_boundary_mask);
	107	}
	108
	109	/*
	110	* Check if adding a bio_vec after bprv with offset would create a gap in
	111	* the SG list. Most drivers don't care about this, but some do.
	112	*/
	113	static inline bool bvec_gap_to_prev(const struct queue_limits *lim,
	114	struct bio_vec *bprv, unsigned int offset)
	115	{
	116	if (!lim->virt_boundary_mask)
	117	return false;
	118	return __bvec_gap_to_prev(lim, bprv, offset);
	119	}
	120
	121	static inline bool rq_mergeable(struct request *rq)
	122	{
	123	if (blk_rq_is_passthrough(rq))
	124	return false;
	125
	126	if (req_op(rq) == REQ_OP_FLUSH)
	127	return false;
	128
	129	if (req_op(rq) == REQ_OP_WRITE_ZEROES)
	130	return false;
	131
	132	if (req_op(rq) == REQ_OP_ZONE_APPEND)
	133	return false;
	134
	135	if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
	136	return false;
	137	if (rq->rq_flags & RQF_NOMERGE_FLAGS)
	138	return false;
	139
	140	return true;
	141	}
	142
	143	/*
	144	* There are two different ways to handle DISCARD merges:
	145	* 1) If max_discard_segments > 1, the driver treats every bio as a range and
	146	* send the bios to controller together. The ranges don't need to be
	147	* contiguous.
	148	* 2) Otherwise, the request will be normal read/write requests. The ranges
	149	* need to be contiguous.
	150	*/
	151	static inline bool blk_discard_mergable(struct request *req)
	152	{
	153	if (req_op(req) == REQ_OP_DISCARD &&
	154	queue_max_discard_segments(req->q) > 1)
	155	return true;
	156	return false;
	157	}
	158
	159	static inline unsigned int blk_rq_get_max_segments(struct request *rq)
	160	{
	161	if (req_op(rq) == REQ_OP_DISCARD)
	162	return queue_max_discard_segments(rq->q);
	163	return queue_max_segments(rq->q);
	164	}
	165
	166	static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
	167	enum req_op op)
	168	{
	169	if (unlikely(op == REQ_OP_DISCARD \|\| op == REQ_OP_SECURE_ERASE))
	170	return min(q->limits.max_discard_sectors,
	171	UINT_MAX >> SECTOR_SHIFT);
	172
	173	if (unlikely(op == REQ_OP_WRITE_ZEROES))
	174	return q->limits.max_write_zeroes_sectors;
	175
	176	return q->limits.max_sectors;
	177	}
	178
	179	#ifdef CONFIG_BLK_DEV_INTEGRITY
	180	void blk_flush_integrity(void);
	181	bool __bio_integrity_endio(struct bio *);
	182	void bio_integrity_free(struct bio *bio);
	183	static inline bool bio_integrity_endio(struct bio *bio)
	184	{
	185	if (bio_integrity(bio))
	186	return __bio_integrity_endio(bio);
	187	return true;
	188	}
	189
	190	bool blk_integrity_merge_rq(struct request_queue , struct request ,
	191	struct request *);
	192	bool blk_integrity_merge_bio(struct request_queue , struct request ,
	193	struct bio *);
	194
	195	static inline bool integrity_req_gap_back_merge(struct request *req,
	196	struct bio *next)
	197	{
	198	struct bio_integrity_payload *bip = bio_integrity(req->bio);
	199	struct bio_integrity_payload *bip_next = bio_integrity(next);
	200
	201	return bvec_gap_to_prev(&req->q->limits,
	202	&bip->bip_vec[bip->bip_vcnt - 1],
	203	bip_next->bip_vec[0].bv_offset);
	204	}
	205
	206	static inline bool integrity_req_gap_front_merge(struct request *req,
	207	struct bio *bio)
	208	{
	209	struct bio_integrity_payload *bip = bio_integrity(bio);
	210	struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
	211
	212	return bvec_gap_to_prev(&req->q->limits,
	213	&bip->bip_vec[bip->bip_vcnt - 1],
	214	bip_next->bip_vec[0].bv_offset);
	215	}
	216
	217	int blk_integrity_add(struct gendisk *disk);
	218	void blk_integrity_del(struct gendisk *);
	219	#else /* CONFIG_BLK_DEV_INTEGRITY */
	220	static inline bool blk_integrity_merge_rq(struct request_queue *rq,
	221	struct request r1, struct request r2)
	222	{
	223	return true;
	224	}
	225	static inline bool blk_integrity_merge_bio(struct request_queue *rq,
	226	struct request r, struct bio b)
	227	{
	228	return true;
	229	}
	230	static inline bool integrity_req_gap_back_merge(struct request *req,
	231	struct bio *next)
	232	{
	233	return false;
	234	}
	235	static inline bool integrity_req_gap_front_merge(struct request *req,
	236	struct bio *bio)
	237	{
	238	return false;
	239	}
	240
	241	static inline void blk_flush_integrity(void)
	242	{
	243	}
	244	static inline bool bio_integrity_endio(struct bio *bio)
	245	{
	246	return true;
	247	}
	248	static inline void bio_integrity_free(struct bio *bio)
	249	{
	250	}
	251	static inline int blk_integrity_add(struct gendisk *disk)
	252	{
	253	return 0;
	254	}
	255	static inline void blk_integrity_del(struct gendisk *disk)
	256	{
	257	}
	258	#endif /* CONFIG_BLK_DEV_INTEGRITY */
	259
	260	unsigned long blk_rq_timeout(unsigned long timeout);
	261	void blk_add_timer(struct request *req);
	262	const char *blk_status_to_str(blk_status_t status);
	263
	264	bool blk_attempt_plug_merge(struct request_queue q, struct bio bio,
	265	unsigned int nr_segs);
	266	bool blk_bio_list_merge(struct request_queue q, struct list_head list,
	267	struct bio *bio, unsigned int nr_segs);
	268
	269	/*
	270	* Plug flush limits
	271	*/
	272	#define BLK_MAX_REQUEST_COUNT 32
	273	#define BLK_PLUG_FLUSH_SIZE (128 * 1024)
	274
	275	/*
	276	* Internal elevator interface
	277	*/
	278	#define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
	279
	280	void blk_insert_flush(struct request *rq);
	281
	282	int elevator_switch(struct request_queue q, struct elevator_type new_e);
	283	void elevator_disable(struct request_queue *q);
	284	void elevator_exit(struct request_queue *q);
	285	int elv_register_queue(struct request_queue *q, bool uevent);
	286	void elv_unregister_queue(struct request_queue *q);
	287
	288	ssize_t part_size_show(struct device dev, struct device_attribute attr,
	289	char *buf);
	290	ssize_t part_stat_show(struct device dev, struct device_attribute attr,
	291	char *buf);
	292	ssize_t part_inflight_show(struct device dev, struct device_attribute attr,
	293	char *buf);
	294	ssize_t part_fail_show(struct device dev, struct device_attribute attr,
	295	char *buf);
	296	ssize_t part_fail_store(struct device dev, struct device_attribute attr,
	297	const char *buf, size_t count);
	298	ssize_t part_timeout_show(struct device , struct device_attribute , char *);
	299	ssize_t part_timeout_store(struct device , struct device_attribute ,
	300	const char *, size_t);
	301
	302	static inline bool bio_may_exceed_limits(struct bio *bio,
	303	const struct queue_limits *lim)
	304	{
	305	switch (bio_op(bio)) {
	306	case REQ_OP_DISCARD:
	307	case REQ_OP_SECURE_ERASE:
	308	case REQ_OP_WRITE_ZEROES:
	309	return true; /* non-trivial splitting decisions */
	310	default:
	311	break;
	312	}
	313
	314	/*
	315	* All drivers must accept single-segments bios that are <= PAGE_SIZE.
	316	* This is a quick and dirty check that relies on the fact that
	317	* bi_io_vec[0] is always valid if a bio has data. The check might
	318	* lead to occasional false negatives when bios are cloned, but compared
	319	* to the performance impact of cloned bios themselves the loop below
	320	* doesn't matter anyway.
	321	*/
	322	return lim->chunk_sectors \|\| bio->bi_vcnt != 1 \|\|
	323	bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;
	324	}
	325
	326	struct bio __bio_split_to_limits(struct bio bio,
	327	const struct queue_limits *lim,
	328	unsigned int *nr_segs);
	329	int ll_back_merge_fn(struct request req, struct bio bio,
	330	unsigned int nr_segs);
	331	bool blk_attempt_req_merge(struct request_queue q, struct request rq,
	332	struct request *next);
	333	unsigned int blk_recalc_rq_segments(struct request *rq);
	334	void blk_rq_set_mixed_merge(struct request *rq);
	335	bool blk_rq_merge_ok(struct request rq, struct bio bio);
	336	enum elv_merge blk_try_merge(struct request rq, struct bio bio);
	337
	338	void blk_set_default_limits(struct queue_limits *lim);
	339	int blk_dev_init(void);
	340
	341	/*
	342	* Contribute to IO statistics IFF:
	343	*
	344	* a) it's attached to a gendisk, and
	345	* b) the queue had IO stats enabled when this request was started
	346	*/
	347	static inline bool blk_do_io_stat(struct request *rq)
	348	{
	349	return (rq->rq_flags & RQF_IO_STAT) && !blk_rq_is_passthrough(rq);
	350	}
	351
	352	void update_io_ticks(struct block_device *part, unsigned long now, bool end);
	353
	354	static inline void req_set_nomerge(struct request_queue q, struct request req)
	355	{
	356	req->cmd_flags \|= REQ_NOMERGE;
	357	if (req == q->last_merge)
	358	q->last_merge = NULL;
	359	}
	360
	361	/*
	362	* Internal io_context interface
	363	*/
	364	struct io_cq ioc_find_get_icq(struct request_queue q);
	365	struct io_cq ioc_lookup_icq(struct request_queue q);
	366	#ifdef CONFIG_BLK_ICQ
	367	void ioc_clear_queue(struct request_queue *q);
	368	#else
	369	static inline void ioc_clear_queue(struct request_queue *q)
	370	{
	371	}
	372	#endif /* CONFIG_BLK_ICQ */
	373
	374	#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
	375	extern ssize_t blk_throtl_sample_time_show(struct request_queue q, char page);
	376	extern ssize_t blk_throtl_sample_time_store(struct request_queue *q,
	377	const char *page, size_t count);
	378	extern void blk_throtl_bio_endio(struct bio *bio);
	379	extern void blk_throtl_stat_add(struct request *rq, u64 time);
	380	#else
	381	static inline void blk_throtl_bio_endio(struct bio *bio) { }
	382	static inline void blk_throtl_stat_add(struct request *rq, u64 time) { }
	383	#endif
	384
	385	struct bio __blk_queue_bounce(struct bio bio, struct request_queue *q);
	386
	387	static inline bool blk_queue_may_bounce(struct request_queue *q)
	388	{
	389	return IS_ENABLED(CONFIG_BOUNCE) &&
	390	q->limits.bounce == BLK_BOUNCE_HIGH &&
	391	max_low_pfn >= max_pfn;
	392	}
	393
	394	static inline struct bio blk_queue_bounce(struct bio bio,
	395	struct request_queue *q)
	396	{
	397	if (unlikely(blk_queue_may_bounce(q) && bio_has_data(bio)))
	398	return __blk_queue_bounce(bio, q);
	399	return bio;
	400	}
	401
	402	#ifdef CONFIG_BLK_DEV_ZONED
	403	void disk_free_zone_bitmaps(struct gendisk *disk);
	404	void disk_clear_zone_settings(struct gendisk *disk);
	405	#else
	406	static inline void disk_free_zone_bitmaps(struct gendisk *disk) {}
	407	static inline void disk_clear_zone_settings(struct gendisk *disk) {}
	408	#endif
	409
	410	int blk_alloc_ext_minor(void);
	411	void blk_free_ext_minor(unsigned int minor);
	412	#define ADDPART_FLAG_NONE 0
	413	#define ADDPART_FLAG_RAID 1
	414	#define ADDPART_FLAG_WHOLEDISK 2
	415	int bdev_add_partition(struct gendisk *disk, int partno, sector_t start,
	416	sector_t length);
	417	int bdev_del_partition(struct gendisk *disk, int partno);
	418	int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start,
	419	sector_t length);
	420	void blk_drop_partitions(struct gendisk *disk);
	421
	422	struct gendisk __alloc_disk_node(struct request_queue q, int node_id,
	423	struct lock_class_key *lkclass);
	424
	425	int bio_add_hw_page(struct request_queue q, struct bio bio,
	426	struct page *page, unsigned int len, unsigned int offset,
	427	unsigned int max_sectors, bool *same_page);
	428
	429	struct request_queue *blk_alloc_queue(int node_id);
	430
	431	int disk_scan_partitions(struct gendisk *disk, fmode_t mode);
	432
	433	int disk_alloc_events(struct gendisk *disk);
	434	void disk_add_events(struct gendisk *disk);
	435	void disk_del_events(struct gendisk *disk);
	436	void disk_release_events(struct gendisk *disk);
	437	void disk_block_events(struct gendisk *disk);
	438	void disk_unblock_events(struct gendisk *disk);
	439	void disk_flush_events(struct gendisk *disk, unsigned int mask);
	440	extern struct device_attribute dev_attr_events;
	441	extern struct device_attribute dev_attr_events_async;
	442	extern struct device_attribute dev_attr_events_poll_msecs;
	443
	444	extern struct attribute_group blk_trace_attr_group;
	445
	446	long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
	447	long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
	448
	449	extern const struct address_space_operations def_blk_aops;
	450
	451	int disk_register_independent_access_ranges(struct gendisk *disk);
	452	void disk_unregister_independent_access_ranges(struct gendisk *disk);
	453
	454	#ifdef CONFIG_FAIL_MAKE_REQUEST
	455	bool should_fail_request(struct block_device *part, unsigned int bytes);
	456	#else /* CONFIG_FAIL_MAKE_REQUEST */
	457	static inline bool should_fail_request(struct block_device *part,
	458	unsigned int bytes)
	459	{
	460	return false;
	461	}
	462	#endif /* CONFIG_FAIL_MAKE_REQUEST */
	463
	464	/*
	465	* Optimized request reference counting. Ideally we'd make timeouts be more
	466	* clever, as that's the only reason we need references at all... But until
	467	* this happens, this is faster than using refcount_t. Also see:
	468	*
	469	* abc54d634334 ("io_uring: switch to atomic_t for io_kiocb reference count")
	470	*/
	471	#define req_ref_zero_or_close_to_overflow(req) \
	472	((unsigned int) atomic_read(&(req->ref)) + 127u <= 127u)
	473
	474	static inline bool req_ref_inc_not_zero(struct request *req)
	475	{
	476	return atomic_inc_not_zero(&req->ref);
	477	}
	478
	479	static inline bool req_ref_put_and_test(struct request *req)
	480	{
	481	WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
	482	return atomic_dec_and_test(&req->ref);
	483	}
	484
	485	static inline void req_ref_set(struct request *req, int value)
	486	{
	487	atomic_set(&req->ref, value);
	488	}
	489
	490	static inline int req_ref_read(struct request *req)
	491	{
	492	return atomic_read(&req->ref);
	493	}
	494
	495	#endif /* BLK_INTERNAL_H */