block/blk.h - third_party/linux - Git at Google

 /* 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;
 	struct lock_class_key	key;
 	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, and
  *	c) it's a file system request
  */
 static inline bool 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;
 }

 /*
  * 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 */
	/* 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;
	struct lock_class_key key;
	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, and
	* c) it's a file system request
	*/
	static inline bool 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;
	}

	/*
	* 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 */