1 #ifndef _LINUX_BLKDEV_H
2 #define _LINUX_BLKDEV_H
4 #include <linux/sched.h>
8 #include <linux/major.h>
9 #include <linux/genhd.h>
10 #include <linux/list.h>
11 #include <linux/llist.h>
12 #include <linux/timer.h>
13 #include <linux/workqueue.h>
14 #include <linux/pagemap.h>
15 #include <linux/backing-dev-defs.h>
16 #include <linux/wait.h>
17 #include <linux/mempool.h>
18 #include <linux/bio.h>
19 #include <linux/stringify.h>
20 #include <linux/gfp.h>
21 #include <linux/bsg.h>
22 #include <linux/smp.h>
23 #include <linux/rcupdate.h>
24 #include <linux/percpu-refcount.h>
25 #include <linux/scatterlist.h>
28 struct scsi_ioctl_command;
31 struct elevator_queue;
37 struct blk_flush_queue;
39 #define BLKDEV_MIN_RQ 4
40 #define BLKDEV_MAX_RQ 128 /* Default maximum */
43 * Maximum number of blkcg policies allowed to be registered concurrently.
44 * Defined here to simplify include dependency.
46 #define BLKCG_MAX_POLS 2
49 typedef void (rq_end_io_fn)(struct request *, int);
51 #define BLK_RL_SYNCFULL (1U << 0)
52 #define BLK_RL_ASYNCFULL (1U << 1)
55 struct request_queue *q; /* the queue this rl belongs to */
56 #ifdef CONFIG_BLK_CGROUP
57 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
60 * count[], starved[], and wait[] are indexed by
61 * BLK_RW_SYNC/BLK_RW_ASYNC
66 wait_queue_head_t wait[2];
71 * request command types
73 enum rq_cmd_type_bits {
74 REQ_TYPE_FS = 1, /* fs request */
75 REQ_TYPE_BLOCK_PC, /* scsi command */
76 REQ_TYPE_DRV_PRIV, /* driver defined types from here */
79 #define BLK_MAX_CDB 16
82 * Try to put the fields that are referenced together in the same cacheline.
84 * If you modify this structure, make sure to update blk_rq_init() and
85 * especially blk_mq_rq_ctx_init() to take care of the added fields.
88 struct list_head queuelist;
90 struct call_single_data csd;
91 unsigned long fifo_time;
94 struct request_queue *q;
95 struct blk_mq_ctx *mq_ctx;
99 unsigned long atomic_flags;
103 /* the following two fields are internal, NEVER access directly */
104 unsigned int __data_len; /* total data len */
105 sector_t __sector; /* sector cursor */
111 * The hash is used inside the scheduler, and killed once the
112 * request reaches the dispatch list. The ipi_list is only used
113 * to queue the request for softirq completion, which is long
114 * after the request has been unhashed (and even removed from
115 * the dispatch list).
118 struct hlist_node hash; /* merge hash */
119 struct list_head ipi_list;
123 * The rb_node is only used inside the io scheduler, requests
124 * are pruned when moved to the dispatch queue. So let the
125 * completion_data share space with the rb_node.
128 struct rb_node rb_node; /* sort/lookup */
129 void *completion_data;
133 * Three pointers are available for the IO schedulers, if they need
134 * more they have to dynamically allocate it. Flush requests are
135 * never put on the IO scheduler. So let the flush fields share
136 * space with the elevator data.
146 struct list_head list;
147 rq_end_io_fn *saved_end_io;
151 struct gendisk *rq_disk;
152 struct hd_struct *part;
153 unsigned long start_time;
154 #ifdef CONFIG_BLK_CGROUP
155 struct request_list *rl; /* rl this rq is alloced from */
156 unsigned long long start_time_ns;
157 unsigned long long io_start_time_ns; /* when passed to hardware */
159 /* Number of scatter-gather DMA addr+len pairs after
160 * physical address coalescing is performed.
162 unsigned short nr_phys_segments;
163 #if defined(CONFIG_BLK_DEV_INTEGRITY)
164 unsigned short nr_integrity_segments;
167 unsigned short ioprio;
169 void *special; /* opaque pointer available for LLD use */
175 * when request is used as a packet command carrier
177 unsigned char __cmd[BLK_MAX_CDB];
179 unsigned short cmd_len;
181 unsigned int extra_len; /* length of alignment and padding */
182 unsigned int sense_len;
183 unsigned int resid_len; /* residual count */
186 unsigned long deadline;
187 struct list_head timeout_list;
188 unsigned int timeout;
192 * completion callback.
194 rq_end_io_fn *end_io;
198 struct request *next_rq;
201 static inline unsigned short req_get_ioprio(struct request *req)
206 #include <linux/elevator.h>
208 struct blk_queue_ctx;
210 typedef void (request_fn_proc) (struct request_queue *q);
211 typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
212 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
213 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
216 typedef void (softirq_done_fn)(struct request *);
217 typedef int (dma_drain_needed_fn)(struct request *);
218 typedef int (lld_busy_fn) (struct request_queue *q);
219 typedef int (bsg_job_fn) (struct bsg_job *);
221 enum blk_eh_timer_return {
227 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
229 enum blk_queue_state {
234 struct blk_queue_tag {
235 struct request **tag_index; /* map of busy tags */
236 unsigned long *tag_map; /* bit map of free/busy tags */
237 int busy; /* current depth */
238 int max_depth; /* what we will send to device */
239 int real_max_depth; /* what the array can hold */
240 atomic_t refcnt; /* map can be shared */
241 int alloc_policy; /* tag allocation policy */
242 int next_tag; /* next tag */
244 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
245 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
247 #define BLK_SCSI_MAX_CMDS (256)
248 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
250 struct queue_limits {
251 unsigned long bounce_pfn;
252 unsigned long seg_boundary_mask;
253 unsigned long virt_boundary_mask;
255 unsigned int max_hw_sectors;
256 unsigned int chunk_sectors;
257 unsigned int max_sectors;
258 unsigned int max_segment_size;
259 unsigned int physical_block_size;
260 unsigned int alignment_offset;
263 unsigned int max_discard_sectors;
264 unsigned int max_hw_discard_sectors;
265 unsigned int max_write_same_sectors;
266 unsigned int discard_granularity;
267 unsigned int discard_alignment;
269 unsigned short logical_block_size;
270 unsigned short max_segments;
271 unsigned short max_integrity_segments;
273 unsigned char misaligned;
274 unsigned char discard_misaligned;
275 unsigned char cluster;
276 unsigned char discard_zeroes_data;
277 unsigned char raid_partial_stripes_expensive;
280 struct request_queue {
282 * Together with queue_head for cacheline sharing
284 struct list_head queue_head;
285 struct request *last_merge;
286 struct elevator_queue *elevator;
287 int nr_rqs[2]; /* # allocated [a]sync rqs */
288 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
291 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
292 * is used, root blkg allocates from @q->root_rl and all other
293 * blkgs from their own blkg->rl. Which one to use should be
294 * determined using bio_request_list().
296 struct request_list root_rl;
298 request_fn_proc *request_fn;
299 make_request_fn *make_request_fn;
300 prep_rq_fn *prep_rq_fn;
301 unprep_rq_fn *unprep_rq_fn;
302 softirq_done_fn *softirq_done_fn;
303 rq_timed_out_fn *rq_timed_out_fn;
304 dma_drain_needed_fn *dma_drain_needed;
305 lld_busy_fn *lld_busy_fn;
307 struct blk_mq_ops *mq_ops;
309 unsigned int *mq_map;
312 struct blk_mq_ctx __percpu *queue_ctx;
313 unsigned int nr_queues;
315 /* hw dispatch queues */
316 struct blk_mq_hw_ctx **queue_hw_ctx;
317 unsigned int nr_hw_queues;
320 * Dispatch queue sorting
323 struct request *boundary_rq;
326 * Delayed queue handling
328 struct delayed_work delay_work;
330 struct backing_dev_info backing_dev_info;
333 * The queue owner gets to use this for whatever they like.
334 * ll_rw_blk doesn't touch it.
339 * various queue flags, see QUEUE_* below
341 unsigned long queue_flags;
344 * ida allocated id for this queue. Used to index queues from
350 * queue needs bounce pages for pages above this limit
355 * protects queue structures from reentrancy. ->__queue_lock should
356 * _never_ be used directly, it is queue private. always use
359 spinlock_t __queue_lock;
360 spinlock_t *queue_lock;
370 struct kobject mq_kobj;
375 unsigned int nr_pending;
381 unsigned long nr_requests; /* Max # of requests */
382 unsigned int nr_congestion_on;
383 unsigned int nr_congestion_off;
384 unsigned int nr_batching;
386 unsigned int dma_drain_size;
387 void *dma_drain_buffer;
388 unsigned int dma_pad_mask;
389 unsigned int dma_alignment;
391 struct blk_queue_tag *queue_tags;
392 struct list_head tag_busy_list;
394 unsigned int nr_sorted;
395 unsigned int in_flight[2];
397 * Number of active block driver functions for which blk_drain_queue()
398 * must wait. Must be incremented around functions that unlock the
399 * queue_lock internally, e.g. scsi_request_fn().
401 unsigned int request_fn_active;
403 unsigned int rq_timeout;
404 struct timer_list timeout;
405 struct list_head timeout_list;
407 struct list_head icq_list;
408 #ifdef CONFIG_BLK_CGROUP
409 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
410 struct blkcg_gq *root_blkg;
411 struct list_head blkg_list;
414 struct queue_limits limits;
419 unsigned int sg_timeout;
420 unsigned int sg_reserved_size;
422 #ifdef CONFIG_BLK_DEV_IO_TRACE
423 struct blk_trace *blk_trace;
426 * for flush operations
428 unsigned int flush_flags;
429 unsigned int flush_not_queueable:1;
430 struct blk_flush_queue *fq;
432 struct list_head requeue_list;
433 spinlock_t requeue_lock;
434 struct work_struct requeue_work;
436 struct mutex sysfs_lock;
439 atomic_t mq_freeze_depth;
441 #if defined(CONFIG_BLK_DEV_BSG)
442 bsg_job_fn *bsg_job_fn;
444 struct bsg_class_device bsg_dev;
447 #ifdef CONFIG_BLK_DEV_THROTTLING
449 struct throtl_data *td;
451 struct rcu_head rcu_head;
452 wait_queue_head_t mq_freeze_wq;
453 struct percpu_ref mq_usage_counter;
454 struct list_head all_q_node;
456 struct blk_mq_tag_set *tag_set;
457 struct list_head tag_set_list;
458 struct bio_set *bio_split;
460 bool mq_sysfs_init_done;
463 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
464 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
465 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
466 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
467 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
468 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
469 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
470 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
471 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
472 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
473 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
474 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
475 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
476 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
477 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
478 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
479 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
480 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
481 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
482 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
483 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
484 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
486 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
487 (1 << QUEUE_FLAG_STACKABLE) | \
488 (1 << QUEUE_FLAG_SAME_COMP) | \
489 (1 << QUEUE_FLAG_ADD_RANDOM))
491 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
492 (1 << QUEUE_FLAG_STACKABLE) | \
493 (1 << QUEUE_FLAG_SAME_COMP))
495 static inline void queue_lockdep_assert_held(struct request_queue *q)
498 lockdep_assert_held(q->queue_lock);
501 static inline void queue_flag_set_unlocked(unsigned int flag,
502 struct request_queue *q)
504 __set_bit(flag, &q->queue_flags);
507 static inline int queue_flag_test_and_clear(unsigned int flag,
508 struct request_queue *q)
510 queue_lockdep_assert_held(q);
512 if (test_bit(flag, &q->queue_flags)) {
513 __clear_bit(flag, &q->queue_flags);
520 static inline int queue_flag_test_and_set(unsigned int flag,
521 struct request_queue *q)
523 queue_lockdep_assert_held(q);
525 if (!test_bit(flag, &q->queue_flags)) {
526 __set_bit(flag, &q->queue_flags);
533 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
535 queue_lockdep_assert_held(q);
536 __set_bit(flag, &q->queue_flags);
539 static inline void queue_flag_clear_unlocked(unsigned int flag,
540 struct request_queue *q)
542 __clear_bit(flag, &q->queue_flags);
545 static inline int queue_in_flight(struct request_queue *q)
547 return q->in_flight[0] + q->in_flight[1];
550 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
552 queue_lockdep_assert_held(q);
553 __clear_bit(flag, &q->queue_flags);
556 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
557 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
558 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
559 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
560 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
561 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
562 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
563 #define blk_queue_noxmerges(q) \
564 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
565 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
566 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
567 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
568 #define blk_queue_stackable(q) \
569 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
570 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
571 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
572 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
574 #define blk_noretry_request(rq) \
575 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
576 REQ_FAILFAST_DRIVER))
578 #define blk_account_rq(rq) \
579 (((rq)->cmd_flags & REQ_STARTED) && \
580 ((rq)->cmd_type == REQ_TYPE_FS))
582 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
583 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
584 /* rq->queuelist of dequeued request must be list_empty() */
585 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
587 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
589 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1))
592 * Driver can handle struct request, if it either has an old style
593 * request_fn defined, or is blk-mq based.
595 static inline bool queue_is_rq_based(struct request_queue *q)
597 return q->request_fn || q->mq_ops;
600 static inline unsigned int blk_queue_cluster(struct request_queue *q)
602 return q->limits.cluster;
606 * We regard a request as sync, if either a read or a sync write
608 static inline bool rw_is_sync(unsigned int rw_flags)
610 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
613 static inline bool rq_is_sync(struct request *rq)
615 return rw_is_sync(rq->cmd_flags);
618 static inline bool blk_rl_full(struct request_list *rl, bool sync)
620 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
622 return rl->flags & flag;
625 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
627 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
632 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
634 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
639 static inline bool rq_mergeable(struct request *rq)
641 if (rq->cmd_type != REQ_TYPE_FS)
644 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
650 static inline bool blk_check_merge_flags(unsigned int flags1,
653 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
656 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
659 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
665 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
667 if (bio_data(a) == bio_data(b))
674 * q->prep_rq_fn return values
676 #define BLKPREP_OK 0 /* serve it */
677 #define BLKPREP_KILL 1 /* fatal error, kill */
678 #define BLKPREP_DEFER 2 /* leave on queue */
680 extern unsigned long blk_max_low_pfn, blk_max_pfn;
683 * standard bounce addresses:
685 * BLK_BOUNCE_HIGH : bounce all highmem pages
686 * BLK_BOUNCE_ANY : don't bounce anything
687 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
690 #if BITS_PER_LONG == 32
691 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
693 #define BLK_BOUNCE_HIGH -1ULL
695 #define BLK_BOUNCE_ANY (-1ULL)
696 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
699 * default timeout for SG_IO if none specified
701 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
702 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
705 extern int init_emergency_isa_pool(void);
706 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
708 static inline int init_emergency_isa_pool(void)
712 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
715 #endif /* CONFIG_MMU */
721 unsigned long offset;
726 struct req_iterator {
727 struct bvec_iter iter;
731 /* This should not be used directly - use rq_for_each_segment */
732 #define for_each_bio(_bio) \
733 for (; _bio; _bio = _bio->bi_next)
734 #define __rq_for_each_bio(_bio, rq) \
736 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
738 #define rq_for_each_segment(bvl, _rq, _iter) \
739 __rq_for_each_bio(_iter.bio, _rq) \
740 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
742 #define rq_iter_last(bvec, _iter) \
743 (_iter.bio->bi_next == NULL && \
744 bio_iter_last(bvec, _iter.iter))
746 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
747 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
749 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
750 extern void rq_flush_dcache_pages(struct request *rq);
752 static inline void rq_flush_dcache_pages(struct request *rq)
757 extern int blk_register_queue(struct gendisk *disk);
758 extern void blk_unregister_queue(struct gendisk *disk);
759 extern void generic_make_request(struct bio *bio);
760 extern void blk_rq_init(struct request_queue *q, struct request *rq);
761 extern void blk_put_request(struct request *);
762 extern void __blk_put_request(struct request_queue *, struct request *);
763 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
764 extern struct request *blk_make_request(struct request_queue *, struct bio *,
766 extern void blk_rq_set_block_pc(struct request *);
767 extern void blk_requeue_request(struct request_queue *, struct request *);
768 extern void blk_add_request_payload(struct request *rq, struct page *page,
770 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
771 extern int blk_lld_busy(struct request_queue *q);
772 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
773 struct bio_set *bs, gfp_t gfp_mask,
774 int (*bio_ctr)(struct bio *, struct bio *, void *),
776 extern void blk_rq_unprep_clone(struct request *rq);
777 extern int blk_insert_cloned_request(struct request_queue *q,
779 extern void blk_delay_queue(struct request_queue *, unsigned long);
780 extern void blk_queue_split(struct request_queue *, struct bio **,
782 extern void blk_recount_segments(struct request_queue *, struct bio *);
783 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
784 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
785 unsigned int, void __user *);
786 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
787 unsigned int, void __user *);
788 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
789 struct scsi_ioctl_command __user *);
791 extern void blk_start_queue(struct request_queue *q);
792 extern void blk_stop_queue(struct request_queue *q);
793 extern void blk_sync_queue(struct request_queue *q);
794 extern void __blk_stop_queue(struct request_queue *q);
795 extern void __blk_run_queue(struct request_queue *q);
796 extern void __blk_run_queue_uncond(struct request_queue *q);
797 extern void blk_run_queue(struct request_queue *);
798 extern void blk_run_queue_async(struct request_queue *q);
799 extern int blk_rq_map_user(struct request_queue *, struct request *,
800 struct rq_map_data *, void __user *, unsigned long,
802 extern int blk_rq_unmap_user(struct bio *);
803 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
804 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
805 struct rq_map_data *, const struct iov_iter *,
807 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
808 struct request *, int);
809 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
810 struct request *, int, rq_end_io_fn *);
812 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
814 return bdev->bd_disk->queue; /* this is never NULL */
818 * blk_rq_pos() : the current sector
819 * blk_rq_bytes() : bytes left in the entire request
820 * blk_rq_cur_bytes() : bytes left in the current segment
821 * blk_rq_err_bytes() : bytes left till the next error boundary
822 * blk_rq_sectors() : sectors left in the entire request
823 * blk_rq_cur_sectors() : sectors left in the current segment
825 static inline sector_t blk_rq_pos(const struct request *rq)
830 static inline unsigned int blk_rq_bytes(const struct request *rq)
832 return rq->__data_len;
835 static inline int blk_rq_cur_bytes(const struct request *rq)
837 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
840 extern unsigned int blk_rq_err_bytes(const struct request *rq);
842 static inline unsigned int blk_rq_sectors(const struct request *rq)
844 return blk_rq_bytes(rq) >> 9;
847 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
849 return blk_rq_cur_bytes(rq) >> 9;
852 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
853 unsigned int cmd_flags)
855 if (unlikely(cmd_flags & REQ_DISCARD))
856 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
858 if (unlikely(cmd_flags & REQ_WRITE_SAME))
859 return q->limits.max_write_same_sectors;
861 return q->limits.max_sectors;
865 * Return maximum size of a request at given offset. Only valid for
866 * file system requests.
868 static inline unsigned int blk_max_size_offset(struct request_queue *q,
871 if (!q->limits.chunk_sectors)
872 return q->limits.max_sectors;
874 return q->limits.chunk_sectors -
875 (offset & (q->limits.chunk_sectors - 1));
878 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
880 struct request_queue *q = rq->q;
882 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
883 return q->limits.max_hw_sectors;
885 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD))
886 return blk_queue_get_max_sectors(q, rq->cmd_flags);
888 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
889 blk_queue_get_max_sectors(q, rq->cmd_flags));
892 static inline unsigned int blk_rq_count_bios(struct request *rq)
894 unsigned int nr_bios = 0;
897 __rq_for_each_bio(bio, rq)
904 * Request issue related functions.
906 extern struct request *blk_peek_request(struct request_queue *q);
907 extern void blk_start_request(struct request *rq);
908 extern struct request *blk_fetch_request(struct request_queue *q);
911 * Request completion related functions.
913 * blk_update_request() completes given number of bytes and updates
914 * the request without completing it.
916 * blk_end_request() and friends. __blk_end_request() must be called
917 * with the request queue spinlock acquired.
919 * Several drivers define their own end_request and call
920 * blk_end_request() for parts of the original function.
921 * This prevents code duplication in drivers.
923 extern bool blk_update_request(struct request *rq, int error,
924 unsigned int nr_bytes);
925 extern void blk_finish_request(struct request *rq, int error);
926 extern bool blk_end_request(struct request *rq, int error,
927 unsigned int nr_bytes);
928 extern void blk_end_request_all(struct request *rq, int error);
929 extern bool blk_end_request_cur(struct request *rq, int error);
930 extern bool blk_end_request_err(struct request *rq, int error);
931 extern bool __blk_end_request(struct request *rq, int error,
932 unsigned int nr_bytes);
933 extern void __blk_end_request_all(struct request *rq, int error);
934 extern bool __blk_end_request_cur(struct request *rq, int error);
935 extern bool __blk_end_request_err(struct request *rq, int error);
937 extern void blk_complete_request(struct request *);
938 extern void __blk_complete_request(struct request *);
939 extern void blk_abort_request(struct request *);
940 extern void blk_unprep_request(struct request *);
943 * Access functions for manipulating queue properties
945 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
946 spinlock_t *lock, int node_id);
947 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
948 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
949 request_fn_proc *, spinlock_t *);
950 extern void blk_cleanup_queue(struct request_queue *);
951 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
952 extern void blk_queue_bounce_limit(struct request_queue *, u64);
953 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
954 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
955 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
956 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
957 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
958 extern void blk_queue_max_discard_sectors(struct request_queue *q,
959 unsigned int max_discard_sectors);
960 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
961 unsigned int max_write_same_sectors);
962 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
963 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
964 extern void blk_queue_alignment_offset(struct request_queue *q,
965 unsigned int alignment);
966 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
967 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
968 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
969 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
970 extern void blk_set_default_limits(struct queue_limits *lim);
971 extern void blk_set_stacking_limits(struct queue_limits *lim);
972 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
974 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
976 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
978 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
979 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
980 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
981 extern int blk_queue_dma_drain(struct request_queue *q,
982 dma_drain_needed_fn *dma_drain_needed,
983 void *buf, unsigned int size);
984 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
985 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
986 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
987 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
988 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
989 extern void blk_queue_dma_alignment(struct request_queue *, int);
990 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
991 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
992 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
993 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
994 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
995 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
996 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
998 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
999 extern void blk_dump_rq_flags(struct request *, char *);
1000 extern long nr_blockdev_pages(void);
1002 bool __must_check blk_get_queue(struct request_queue *);
1003 struct request_queue *blk_alloc_queue(gfp_t);
1004 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1005 extern void blk_put_queue(struct request_queue *);
1006 extern void blk_set_queue_dying(struct request_queue *);
1009 * block layer runtime pm functions
1012 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1013 extern int blk_pre_runtime_suspend(struct request_queue *q);
1014 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1015 extern void blk_pre_runtime_resume(struct request_queue *q);
1016 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1018 static inline void blk_pm_runtime_init(struct request_queue *q,
1019 struct device *dev) {}
1020 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1024 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1025 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1026 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1030 * blk_plug permits building a queue of related requests by holding the I/O
1031 * fragments for a short period. This allows merging of sequential requests
1032 * into single larger request. As the requests are moved from a per-task list to
1033 * the device's request_queue in a batch, this results in improved scalability
1034 * as the lock contention for request_queue lock is reduced.
1036 * It is ok not to disable preemption when adding the request to the plug list
1037 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1038 * the plug list when the task sleeps by itself. For details, please see
1039 * schedule() where blk_schedule_flush_plug() is called.
1042 struct list_head list; /* requests */
1043 struct list_head mq_list; /* blk-mq requests */
1044 struct list_head cb_list; /* md requires an unplug callback */
1046 #define BLK_MAX_REQUEST_COUNT 16
1049 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1050 struct blk_plug_cb {
1051 struct list_head list;
1052 blk_plug_cb_fn callback;
1055 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1056 void *data, int size);
1057 extern void blk_start_plug(struct blk_plug *);
1058 extern void blk_finish_plug(struct blk_plug *);
1059 extern void blk_flush_plug_list(struct blk_plug *, bool);
1061 static inline void blk_flush_plug(struct task_struct *tsk)
1063 struct blk_plug *plug = tsk->plug;
1066 blk_flush_plug_list(plug, false);
1069 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1071 struct blk_plug *plug = tsk->plug;
1074 blk_flush_plug_list(plug, true);
1077 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1079 struct blk_plug *plug = tsk->plug;
1082 (!list_empty(&plug->list) ||
1083 !list_empty(&plug->mq_list) ||
1084 !list_empty(&plug->cb_list));
1090 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1091 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1092 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1093 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1094 extern void blk_queue_free_tags(struct request_queue *);
1095 extern int blk_queue_resize_tags(struct request_queue *, int);
1096 extern void blk_queue_invalidate_tags(struct request_queue *);
1097 extern struct blk_queue_tag *blk_init_tags(int, int);
1098 extern void blk_free_tags(struct blk_queue_tag *);
1100 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1103 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1105 return bqt->tag_index[tag];
1108 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1110 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1111 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1112 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1113 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1114 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1115 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1116 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1117 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1118 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1120 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1121 nr_blocks << (sb->s_blocksize_bits - 9),
1124 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1125 sector_t nr_blocks, gfp_t gfp_mask)
1127 return blkdev_issue_zeroout(sb->s_bdev,
1128 block << (sb->s_blocksize_bits - 9),
1129 nr_blocks << (sb->s_blocksize_bits - 9),
1133 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1135 enum blk_default_limits {
1136 BLK_MAX_SEGMENTS = 128,
1137 BLK_SAFE_MAX_SECTORS = 255,
1138 BLK_DEF_MAX_SECTORS = 2560,
1139 BLK_MAX_SEGMENT_SIZE = 65536,
1140 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1143 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1145 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1147 return q->limits.bounce_pfn;
1150 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1152 return q->limits.seg_boundary_mask;
1155 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1157 return q->limits.virt_boundary_mask;
1160 static inline unsigned int queue_max_sectors(struct request_queue *q)
1162 return q->limits.max_sectors;
1165 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1167 return q->limits.max_hw_sectors;
1170 static inline unsigned short queue_max_segments(struct request_queue *q)
1172 return q->limits.max_segments;
1175 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1177 return q->limits.max_segment_size;
1180 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1184 if (q && q->limits.logical_block_size)
1185 retval = q->limits.logical_block_size;
1190 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1192 return queue_logical_block_size(bdev_get_queue(bdev));
1195 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1197 return q->limits.physical_block_size;
1200 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1202 return queue_physical_block_size(bdev_get_queue(bdev));
1205 static inline unsigned int queue_io_min(struct request_queue *q)
1207 return q->limits.io_min;
1210 static inline int bdev_io_min(struct block_device *bdev)
1212 return queue_io_min(bdev_get_queue(bdev));
1215 static inline unsigned int queue_io_opt(struct request_queue *q)
1217 return q->limits.io_opt;
1220 static inline int bdev_io_opt(struct block_device *bdev)
1222 return queue_io_opt(bdev_get_queue(bdev));
1225 static inline int queue_alignment_offset(struct request_queue *q)
1227 if (q->limits.misaligned)
1230 return q->limits.alignment_offset;
1233 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1235 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1236 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1238 return (granularity + lim->alignment_offset - alignment) % granularity;
1241 static inline int bdev_alignment_offset(struct block_device *bdev)
1243 struct request_queue *q = bdev_get_queue(bdev);
1245 if (q->limits.misaligned)
1248 if (bdev != bdev->bd_contains)
1249 return bdev->bd_part->alignment_offset;
1251 return q->limits.alignment_offset;
1254 static inline int queue_discard_alignment(struct request_queue *q)
1256 if (q->limits.discard_misaligned)
1259 return q->limits.discard_alignment;
1262 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1264 unsigned int alignment, granularity, offset;
1266 if (!lim->max_discard_sectors)
1269 /* Why are these in bytes, not sectors? */
1270 alignment = lim->discard_alignment >> 9;
1271 granularity = lim->discard_granularity >> 9;
1275 /* Offset of the partition start in 'granularity' sectors */
1276 offset = sector_div(sector, granularity);
1278 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1279 offset = (granularity + alignment - offset) % granularity;
1281 /* Turn it back into bytes, gaah */
1285 static inline int bdev_discard_alignment(struct block_device *bdev)
1287 struct request_queue *q = bdev_get_queue(bdev);
1289 if (bdev != bdev->bd_contains)
1290 return bdev->bd_part->discard_alignment;
1292 return q->limits.discard_alignment;
1295 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1297 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1303 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1305 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1308 static inline unsigned int bdev_write_same(struct block_device *bdev)
1310 struct request_queue *q = bdev_get_queue(bdev);
1313 return q->limits.max_write_same_sectors;
1318 static inline int queue_dma_alignment(struct request_queue *q)
1320 return q ? q->dma_alignment : 511;
1323 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1326 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1327 return !(addr & alignment) && !(len & alignment);
1330 /* assumes size > 256 */
1331 static inline unsigned int blksize_bits(unsigned int size)
1333 unsigned int bits = 8;
1337 } while (size > 256);
1341 static inline unsigned int block_size(struct block_device *bdev)
1343 return bdev->bd_block_size;
1346 static inline bool queue_flush_queueable(struct request_queue *q)
1348 return !q->flush_not_queueable;
1351 typedef struct {struct page *v;} Sector;
1353 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1355 static inline void put_dev_sector(Sector p)
1357 page_cache_release(p.v);
1361 * Check if adding a bio_vec after bprv with offset would create a gap in
1362 * the SG list. Most drivers don't care about this, but some do.
1364 static inline bool bvec_gap_to_prev(struct request_queue *q,
1365 struct bio_vec *bprv, unsigned int offset)
1367 if (!queue_virt_boundary(q))
1370 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1373 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1376 if (!bio_has_data(prev))
1379 return bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1],
1380 next->bi_io_vec[0].bv_offset);
1383 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1385 return bio_will_gap(req->q, req->biotail, bio);
1388 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1390 return bio_will_gap(req->q, bio, req->bio);
1394 int kblockd_schedule_work(struct work_struct *work);
1395 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1396 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1398 #ifdef CONFIG_BLK_CGROUP
1400 * This should not be using sched_clock(). A real patch is in progress
1401 * to fix this up, until that is in place we need to disable preemption
1402 * around sched_clock() in this function and set_io_start_time_ns().
1404 static inline void set_start_time_ns(struct request *req)
1407 req->start_time_ns = sched_clock();
1411 static inline void set_io_start_time_ns(struct request *req)
1414 req->io_start_time_ns = sched_clock();
1418 static inline uint64_t rq_start_time_ns(struct request *req)
1420 return req->start_time_ns;
1423 static inline uint64_t rq_io_start_time_ns(struct request *req)
1425 return req->io_start_time_ns;
1428 static inline void set_start_time_ns(struct request *req) {}
1429 static inline void set_io_start_time_ns(struct request *req) {}
1430 static inline uint64_t rq_start_time_ns(struct request *req)
1434 static inline uint64_t rq_io_start_time_ns(struct request *req)
1440 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1441 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1442 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1443 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1445 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1447 enum blk_integrity_flags {
1448 BLK_INTEGRITY_VERIFY = 1 << 0,
1449 BLK_INTEGRITY_GENERATE = 1 << 1,
1450 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1451 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1454 struct blk_integrity_iter {
1458 unsigned int data_size;
1459 unsigned short interval;
1460 const char *disk_name;
1463 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1465 struct blk_integrity {
1466 integrity_processing_fn *generate_fn;
1467 integrity_processing_fn *verify_fn;
1469 unsigned short flags;
1470 unsigned short tuple_size;
1471 unsigned short interval;
1472 unsigned short tag_size;
1476 struct kobject kobj;
1479 extern bool blk_integrity_is_initialized(struct gendisk *);
1480 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1481 extern void blk_integrity_unregister(struct gendisk *);
1482 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1483 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1484 struct scatterlist *);
1485 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1486 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1488 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1492 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1494 return bdev->bd_disk->integrity;
1497 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1499 return disk->integrity;
1502 static inline bool blk_integrity_rq(struct request *rq)
1504 return rq->cmd_flags & REQ_INTEGRITY;
1507 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1510 q->limits.max_integrity_segments = segs;
1513 static inline unsigned short
1514 queue_max_integrity_segments(struct request_queue *q)
1516 return q->limits.max_integrity_segments;
1519 static inline bool integrity_req_gap_back_merge(struct request *req,
1522 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1523 struct bio_integrity_payload *bip_next = bio_integrity(next);
1525 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1526 bip_next->bip_vec[0].bv_offset);
1529 static inline bool integrity_req_gap_front_merge(struct request *req,
1532 struct bio_integrity_payload *bip = bio_integrity(bio);
1533 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1535 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1536 bip_next->bip_vec[0].bv_offset);
1539 #else /* CONFIG_BLK_DEV_INTEGRITY */
1542 struct block_device;
1544 struct blk_integrity;
1546 static inline int blk_integrity_rq(struct request *rq)
1550 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1555 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1557 struct scatterlist *s)
1561 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1565 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1569 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1573 static inline int blk_integrity_register(struct gendisk *d,
1574 struct blk_integrity *b)
1578 static inline void blk_integrity_unregister(struct gendisk *d)
1581 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1585 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1589 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1595 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1601 static inline bool blk_integrity_is_initialized(struct gendisk *g)
1605 static inline bool integrity_req_gap_back_merge(struct request *req,
1610 static inline bool integrity_req_gap_front_merge(struct request *req,
1616 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1618 struct block_device_operations {
1619 int (*open) (struct block_device *, fmode_t);
1620 void (*release) (struct gendisk *, fmode_t);
1621 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1622 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1623 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1624 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
1625 unsigned long *pfn);
1626 unsigned int (*check_events) (struct gendisk *disk,
1627 unsigned int clearing);
1628 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1629 int (*media_changed) (struct gendisk *);
1630 void (*unlock_native_capacity) (struct gendisk *);
1631 int (*revalidate_disk) (struct gendisk *);
1632 int (*getgeo)(struct block_device *, struct hd_geometry *);
1633 /* this callback is with swap_lock and sometimes page table lock held */
1634 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1635 struct module *owner;
1638 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1640 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1641 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1642 struct writeback_control *);
1643 extern long bdev_direct_access(struct block_device *, sector_t,
1644 void __pmem **addr, unsigned long *pfn, long size);
1645 #else /* CONFIG_BLOCK */
1647 struct block_device;
1650 * stubs for when the block layer is configured out
1652 #define buffer_heads_over_limit 0
1654 static inline long nr_blockdev_pages(void)
1662 static inline void blk_start_plug(struct blk_plug *plug)
1666 static inline void blk_finish_plug(struct blk_plug *plug)
1670 static inline void blk_flush_plug(struct task_struct *task)
1674 static inline void blk_schedule_flush_plug(struct task_struct *task)
1679 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1684 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1685 sector_t *error_sector)
1690 #endif /* CONFIG_BLOCK */