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;
40 #define BLKDEV_MIN_RQ 4
41 #define BLKDEV_MAX_RQ 128 /* Default maximum */
44 * Maximum number of blkcg policies allowed to be registered concurrently.
45 * Defined here to simplify include dependency.
47 #define BLKCG_MAX_POLS 2
50 typedef void (rq_end_io_fn)(struct request *, int);
52 #define BLK_RL_SYNCFULL (1U << 0)
53 #define BLK_RL_ASYNCFULL (1U << 1)
56 struct request_queue *q; /* the queue this rl belongs to */
57 #ifdef CONFIG_BLK_CGROUP
58 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
61 * count[], starved[], and wait[] are indexed by
62 * BLK_RW_SYNC/BLK_RW_ASYNC
67 wait_queue_head_t wait[2];
72 * request command types
74 enum rq_cmd_type_bits {
75 REQ_TYPE_FS = 1, /* fs request */
76 REQ_TYPE_BLOCK_PC, /* scsi command */
77 REQ_TYPE_DRV_PRIV, /* driver defined types from here */
80 #define BLK_MAX_CDB 16
83 * Try to put the fields that are referenced together in the same cacheline.
85 * If you modify this structure, make sure to update blk_rq_init() and
86 * especially blk_mq_rq_ctx_init() to take care of the added fields.
89 struct list_head queuelist;
91 struct call_single_data csd;
92 unsigned long fifo_time;
95 struct request_queue *q;
96 struct blk_mq_ctx *mq_ctx;
100 unsigned long atomic_flags;
104 /* the following two fields are internal, NEVER access directly */
105 unsigned int __data_len; /* total data len */
106 sector_t __sector; /* sector cursor */
112 * The hash is used inside the scheduler, and killed once the
113 * request reaches the dispatch list. The ipi_list is only used
114 * to queue the request for softirq completion, which is long
115 * after the request has been unhashed (and even removed from
116 * the dispatch list).
119 struct hlist_node hash; /* merge hash */
120 struct list_head ipi_list;
124 * The rb_node is only used inside the io scheduler, requests
125 * are pruned when moved to the dispatch queue. So let the
126 * completion_data share space with the rb_node.
129 struct rb_node rb_node; /* sort/lookup */
130 void *completion_data;
134 * Three pointers are available for the IO schedulers, if they need
135 * more they have to dynamically allocate it. Flush requests are
136 * never put on the IO scheduler. So let the flush fields share
137 * space with the elevator data.
147 struct list_head list;
148 rq_end_io_fn *saved_end_io;
152 struct gendisk *rq_disk;
153 struct hd_struct *part;
154 unsigned long start_time;
155 #ifdef CONFIG_BLK_CGROUP
156 struct request_list *rl; /* rl this rq is alloced from */
157 unsigned long long start_time_ns;
158 unsigned long long io_start_time_ns; /* when passed to hardware */
160 /* Number of scatter-gather DMA addr+len pairs after
161 * physical address coalescing is performed.
163 unsigned short nr_phys_segments;
164 #if defined(CONFIG_BLK_DEV_INTEGRITY)
165 unsigned short nr_integrity_segments;
168 unsigned short ioprio;
170 void *special; /* opaque pointer available for LLD use */
176 * when request is used as a packet command carrier
178 unsigned char __cmd[BLK_MAX_CDB];
180 unsigned short cmd_len;
182 unsigned int extra_len; /* length of alignment and padding */
183 unsigned int sense_len;
184 unsigned int resid_len; /* residual count */
187 unsigned long deadline;
188 struct list_head timeout_list;
189 unsigned int timeout;
193 * completion callback.
195 rq_end_io_fn *end_io;
199 struct request *next_rq;
202 static inline unsigned short req_get_ioprio(struct request *req)
207 #include <linux/elevator.h>
209 struct blk_queue_ctx;
211 typedef void (request_fn_proc) (struct request_queue *q);
212 typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
213 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
214 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
217 typedef void (softirq_done_fn)(struct request *);
218 typedef int (dma_drain_needed_fn)(struct request *);
219 typedef int (lld_busy_fn) (struct request_queue *q);
220 typedef int (bsg_job_fn) (struct bsg_job *);
222 enum blk_eh_timer_return {
228 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
230 enum blk_queue_state {
235 struct blk_queue_tag {
236 struct request **tag_index; /* map of busy tags */
237 unsigned long *tag_map; /* bit map of free/busy tags */
238 int busy; /* current depth */
239 int max_depth; /* what we will send to device */
240 int real_max_depth; /* what the array can hold */
241 atomic_t refcnt; /* map can be shared */
242 int alloc_policy; /* tag allocation policy */
243 int next_tag; /* next tag */
245 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
246 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
248 #define BLK_SCSI_MAX_CMDS (256)
249 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
251 struct queue_limits {
252 unsigned long bounce_pfn;
253 unsigned long seg_boundary_mask;
254 unsigned long virt_boundary_mask;
256 unsigned int max_hw_sectors;
257 unsigned int chunk_sectors;
258 unsigned int max_sectors;
259 unsigned int max_segment_size;
260 unsigned int physical_block_size;
261 unsigned int alignment_offset;
264 unsigned int max_discard_sectors;
265 unsigned int max_hw_discard_sectors;
266 unsigned int max_write_same_sectors;
267 unsigned int discard_granularity;
268 unsigned int discard_alignment;
270 unsigned short logical_block_size;
271 unsigned short max_segments;
272 unsigned short max_integrity_segments;
274 unsigned char misaligned;
275 unsigned char discard_misaligned;
276 unsigned char cluster;
277 unsigned char discard_zeroes_data;
278 unsigned char raid_partial_stripes_expensive;
281 struct request_queue {
283 * Together with queue_head for cacheline sharing
285 struct list_head queue_head;
286 struct request *last_merge;
287 struct elevator_queue *elevator;
288 int nr_rqs[2]; /* # allocated [a]sync rqs */
289 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
292 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
293 * is used, root blkg allocates from @q->root_rl and all other
294 * blkgs from their own blkg->rl. Which one to use should be
295 * determined using bio_request_list().
297 struct request_list root_rl;
299 request_fn_proc *request_fn;
300 make_request_fn *make_request_fn;
301 prep_rq_fn *prep_rq_fn;
302 unprep_rq_fn *unprep_rq_fn;
303 softirq_done_fn *softirq_done_fn;
304 rq_timed_out_fn *rq_timed_out_fn;
305 dma_drain_needed_fn *dma_drain_needed;
306 lld_busy_fn *lld_busy_fn;
308 struct blk_mq_ops *mq_ops;
310 unsigned int *mq_map;
313 struct blk_mq_ctx __percpu *queue_ctx;
314 unsigned int nr_queues;
316 /* hw dispatch queues */
317 struct blk_mq_hw_ctx **queue_hw_ctx;
318 unsigned int nr_hw_queues;
321 * Dispatch queue sorting
324 struct request *boundary_rq;
327 * Delayed queue handling
329 struct delayed_work delay_work;
331 struct backing_dev_info backing_dev_info;
334 * The queue owner gets to use this for whatever they like.
335 * ll_rw_blk doesn't touch it.
340 * various queue flags, see QUEUE_* below
342 unsigned long queue_flags;
345 * ida allocated id for this queue. Used to index queues from
351 * queue needs bounce pages for pages above this limit
356 * protects queue structures from reentrancy. ->__queue_lock should
357 * _never_ be used directly, it is queue private. always use
360 spinlock_t __queue_lock;
361 spinlock_t *queue_lock;
371 struct kobject mq_kobj;
373 #ifdef CONFIG_BLK_DEV_INTEGRITY
374 struct blk_integrity integrity;
375 #endif /* CONFIG_BLK_DEV_INTEGRITY */
380 unsigned int nr_pending;
386 unsigned long nr_requests; /* Max # of requests */
387 unsigned int nr_congestion_on;
388 unsigned int nr_congestion_off;
389 unsigned int nr_batching;
391 unsigned int dma_drain_size;
392 void *dma_drain_buffer;
393 unsigned int dma_pad_mask;
394 unsigned int dma_alignment;
396 struct blk_queue_tag *queue_tags;
397 struct list_head tag_busy_list;
399 unsigned int nr_sorted;
400 unsigned int in_flight[2];
402 * Number of active block driver functions for which blk_drain_queue()
403 * must wait. Must be incremented around functions that unlock the
404 * queue_lock internally, e.g. scsi_request_fn().
406 unsigned int request_fn_active;
408 unsigned int rq_timeout;
409 struct timer_list timeout;
410 struct list_head timeout_list;
412 struct list_head icq_list;
413 #ifdef CONFIG_BLK_CGROUP
414 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
415 struct blkcg_gq *root_blkg;
416 struct list_head blkg_list;
419 struct queue_limits limits;
424 unsigned int sg_timeout;
425 unsigned int sg_reserved_size;
427 #ifdef CONFIG_BLK_DEV_IO_TRACE
428 struct blk_trace *blk_trace;
431 * for flush operations
433 unsigned int flush_flags;
434 unsigned int flush_not_queueable:1;
435 struct blk_flush_queue *fq;
437 struct list_head requeue_list;
438 spinlock_t requeue_lock;
439 struct work_struct requeue_work;
441 struct mutex sysfs_lock;
444 atomic_t mq_freeze_depth;
446 #if defined(CONFIG_BLK_DEV_BSG)
447 bsg_job_fn *bsg_job_fn;
449 struct bsg_class_device bsg_dev;
452 #ifdef CONFIG_BLK_DEV_THROTTLING
454 struct throtl_data *td;
456 struct rcu_head rcu_head;
457 wait_queue_head_t mq_freeze_wq;
458 struct percpu_ref q_usage_counter;
459 struct list_head all_q_node;
461 struct blk_mq_tag_set *tag_set;
462 struct list_head tag_set_list;
463 struct bio_set *bio_split;
465 bool mq_sysfs_init_done;
468 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
469 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
470 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
471 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
472 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
473 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
474 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
475 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
476 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
477 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
478 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
479 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
480 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
481 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
482 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
483 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
484 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
485 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
486 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
487 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
488 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
489 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
491 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
492 (1 << QUEUE_FLAG_STACKABLE) | \
493 (1 << QUEUE_FLAG_SAME_COMP) | \
494 (1 << QUEUE_FLAG_ADD_RANDOM))
496 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
497 (1 << QUEUE_FLAG_STACKABLE) | \
498 (1 << QUEUE_FLAG_SAME_COMP))
500 static inline void queue_lockdep_assert_held(struct request_queue *q)
503 lockdep_assert_held(q->queue_lock);
506 static inline void queue_flag_set_unlocked(unsigned int flag,
507 struct request_queue *q)
509 __set_bit(flag, &q->queue_flags);
512 static inline int queue_flag_test_and_clear(unsigned int flag,
513 struct request_queue *q)
515 queue_lockdep_assert_held(q);
517 if (test_bit(flag, &q->queue_flags)) {
518 __clear_bit(flag, &q->queue_flags);
525 static inline int queue_flag_test_and_set(unsigned int flag,
526 struct request_queue *q)
528 queue_lockdep_assert_held(q);
530 if (!test_bit(flag, &q->queue_flags)) {
531 __set_bit(flag, &q->queue_flags);
538 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
540 queue_lockdep_assert_held(q);
541 __set_bit(flag, &q->queue_flags);
544 static inline void queue_flag_clear_unlocked(unsigned int flag,
545 struct request_queue *q)
547 __clear_bit(flag, &q->queue_flags);
550 static inline int queue_in_flight(struct request_queue *q)
552 return q->in_flight[0] + q->in_flight[1];
555 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
557 queue_lockdep_assert_held(q);
558 __clear_bit(flag, &q->queue_flags);
561 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
562 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
563 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
564 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
565 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
566 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
567 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
568 #define blk_queue_noxmerges(q) \
569 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
570 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
571 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
572 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
573 #define blk_queue_stackable(q) \
574 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
575 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
576 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
577 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
579 #define blk_noretry_request(rq) \
580 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
581 REQ_FAILFAST_DRIVER))
583 #define blk_account_rq(rq) \
584 (((rq)->cmd_flags & REQ_STARTED) && \
585 ((rq)->cmd_type == REQ_TYPE_FS))
587 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
588 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
589 /* rq->queuelist of dequeued request must be list_empty() */
590 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
592 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
594 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1))
597 * Driver can handle struct request, if it either has an old style
598 * request_fn defined, or is blk-mq based.
600 static inline bool queue_is_rq_based(struct request_queue *q)
602 return q->request_fn || q->mq_ops;
605 static inline unsigned int blk_queue_cluster(struct request_queue *q)
607 return q->limits.cluster;
611 * We regard a request as sync, if either a read or a sync write
613 static inline bool rw_is_sync(unsigned int rw_flags)
615 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
618 static inline bool rq_is_sync(struct request *rq)
620 return rw_is_sync(rq->cmd_flags);
623 static inline bool blk_rl_full(struct request_list *rl, bool sync)
625 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
627 return rl->flags & flag;
630 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
632 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
637 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
639 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
644 static inline bool rq_mergeable(struct request *rq)
646 if (rq->cmd_type != REQ_TYPE_FS)
649 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
655 static inline bool blk_check_merge_flags(unsigned int flags1,
658 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
661 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
664 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
670 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
672 if (bio_data(a) == bio_data(b))
679 * q->prep_rq_fn return values
681 #define BLKPREP_OK 0 /* serve it */
682 #define BLKPREP_KILL 1 /* fatal error, kill */
683 #define BLKPREP_DEFER 2 /* leave on queue */
685 extern unsigned long blk_max_low_pfn, blk_max_pfn;
688 * standard bounce addresses:
690 * BLK_BOUNCE_HIGH : bounce all highmem pages
691 * BLK_BOUNCE_ANY : don't bounce anything
692 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
695 #if BITS_PER_LONG == 32
696 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
698 #define BLK_BOUNCE_HIGH -1ULL
700 #define BLK_BOUNCE_ANY (-1ULL)
701 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
704 * default timeout for SG_IO if none specified
706 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
707 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
710 extern int init_emergency_isa_pool(void);
711 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
713 static inline int init_emergency_isa_pool(void)
717 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
720 #endif /* CONFIG_MMU */
726 unsigned long offset;
731 struct req_iterator {
732 struct bvec_iter iter;
736 /* This should not be used directly - use rq_for_each_segment */
737 #define for_each_bio(_bio) \
738 for (; _bio; _bio = _bio->bi_next)
739 #define __rq_for_each_bio(_bio, rq) \
741 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
743 #define rq_for_each_segment(bvl, _rq, _iter) \
744 __rq_for_each_bio(_iter.bio, _rq) \
745 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
747 #define rq_iter_last(bvec, _iter) \
748 (_iter.bio->bi_next == NULL && \
749 bio_iter_last(bvec, _iter.iter))
751 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
752 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
754 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
755 extern void rq_flush_dcache_pages(struct request *rq);
757 static inline void rq_flush_dcache_pages(struct request *rq)
762 extern int blk_register_queue(struct gendisk *disk);
763 extern void blk_unregister_queue(struct gendisk *disk);
764 extern void generic_make_request(struct bio *bio);
765 extern void blk_rq_init(struct request_queue *q, struct request *rq);
766 extern void blk_put_request(struct request *);
767 extern void __blk_put_request(struct request_queue *, struct request *);
768 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
769 extern struct request *blk_make_request(struct request_queue *, struct bio *,
771 extern void blk_rq_set_block_pc(struct request *);
772 extern void blk_requeue_request(struct request_queue *, struct request *);
773 extern void blk_add_request_payload(struct request *rq, struct page *page,
775 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
776 extern int blk_lld_busy(struct request_queue *q);
777 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
778 struct bio_set *bs, gfp_t gfp_mask,
779 int (*bio_ctr)(struct bio *, struct bio *, void *),
781 extern void blk_rq_unprep_clone(struct request *rq);
782 extern int blk_insert_cloned_request(struct request_queue *q,
784 extern void blk_delay_queue(struct request_queue *, unsigned long);
785 extern void blk_queue_split(struct request_queue *, struct bio **,
787 extern void blk_recount_segments(struct request_queue *, struct bio *);
788 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
789 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
790 unsigned int, void __user *);
791 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
792 unsigned int, void __user *);
793 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
794 struct scsi_ioctl_command __user *);
796 extern void blk_start_queue(struct request_queue *q);
797 extern void blk_stop_queue(struct request_queue *q);
798 extern void blk_sync_queue(struct request_queue *q);
799 extern void __blk_stop_queue(struct request_queue *q);
800 extern void __blk_run_queue(struct request_queue *q);
801 extern void __blk_run_queue_uncond(struct request_queue *q);
802 extern void blk_run_queue(struct request_queue *);
803 extern void blk_run_queue_async(struct request_queue *q);
804 extern int blk_rq_map_user(struct request_queue *, struct request *,
805 struct rq_map_data *, void __user *, unsigned long,
807 extern int blk_rq_unmap_user(struct bio *);
808 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
809 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
810 struct rq_map_data *, const struct iov_iter *,
812 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
813 struct request *, int);
814 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
815 struct request *, int, rq_end_io_fn *);
817 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
819 return bdev->bd_disk->queue; /* this is never NULL */
823 * blk_rq_pos() : the current sector
824 * blk_rq_bytes() : bytes left in the entire request
825 * blk_rq_cur_bytes() : bytes left in the current segment
826 * blk_rq_err_bytes() : bytes left till the next error boundary
827 * blk_rq_sectors() : sectors left in the entire request
828 * blk_rq_cur_sectors() : sectors left in the current segment
830 static inline sector_t blk_rq_pos(const struct request *rq)
835 static inline unsigned int blk_rq_bytes(const struct request *rq)
837 return rq->__data_len;
840 static inline int blk_rq_cur_bytes(const struct request *rq)
842 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
845 extern unsigned int blk_rq_err_bytes(const struct request *rq);
847 static inline unsigned int blk_rq_sectors(const struct request *rq)
849 return blk_rq_bytes(rq) >> 9;
852 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
854 return blk_rq_cur_bytes(rq) >> 9;
857 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
858 unsigned int cmd_flags)
860 if (unlikely(cmd_flags & REQ_DISCARD))
861 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
863 if (unlikely(cmd_flags & REQ_WRITE_SAME))
864 return q->limits.max_write_same_sectors;
866 return q->limits.max_sectors;
870 * Return maximum size of a request at given offset. Only valid for
871 * file system requests.
873 static inline unsigned int blk_max_size_offset(struct request_queue *q,
876 if (!q->limits.chunk_sectors)
877 return q->limits.max_sectors;
879 return q->limits.chunk_sectors -
880 (offset & (q->limits.chunk_sectors - 1));
883 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
885 struct request_queue *q = rq->q;
887 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
888 return q->limits.max_hw_sectors;
890 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD))
891 return blk_queue_get_max_sectors(q, rq->cmd_flags);
893 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
894 blk_queue_get_max_sectors(q, rq->cmd_flags));
897 static inline unsigned int blk_rq_count_bios(struct request *rq)
899 unsigned int nr_bios = 0;
902 __rq_for_each_bio(bio, rq)
909 * Request issue related functions.
911 extern struct request *blk_peek_request(struct request_queue *q);
912 extern void blk_start_request(struct request *rq);
913 extern struct request *blk_fetch_request(struct request_queue *q);
916 * Request completion related functions.
918 * blk_update_request() completes given number of bytes and updates
919 * the request without completing it.
921 * blk_end_request() and friends. __blk_end_request() must be called
922 * with the request queue spinlock acquired.
924 * Several drivers define their own end_request and call
925 * blk_end_request() for parts of the original function.
926 * This prevents code duplication in drivers.
928 extern bool blk_update_request(struct request *rq, int error,
929 unsigned int nr_bytes);
930 extern void blk_finish_request(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);
936 extern bool __blk_end_request(struct request *rq, int error,
937 unsigned int nr_bytes);
938 extern void __blk_end_request_all(struct request *rq, int error);
939 extern bool __blk_end_request_cur(struct request *rq, int error);
940 extern bool __blk_end_request_err(struct request *rq, int error);
942 extern void blk_complete_request(struct request *);
943 extern void __blk_complete_request(struct request *);
944 extern void blk_abort_request(struct request *);
945 extern void blk_unprep_request(struct request *);
948 * Access functions for manipulating queue properties
950 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
951 spinlock_t *lock, int node_id);
952 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
953 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
954 request_fn_proc *, spinlock_t *);
955 extern void blk_cleanup_queue(struct request_queue *);
956 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
957 extern void blk_queue_bounce_limit(struct request_queue *, u64);
958 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
959 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
960 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
961 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
962 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
963 extern void blk_queue_max_discard_sectors(struct request_queue *q,
964 unsigned int max_discard_sectors);
965 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
966 unsigned int max_write_same_sectors);
967 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
968 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
969 extern void blk_queue_alignment_offset(struct request_queue *q,
970 unsigned int alignment);
971 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
972 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
973 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
974 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
975 extern void blk_set_default_limits(struct queue_limits *lim);
976 extern void blk_set_stacking_limits(struct queue_limits *lim);
977 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
979 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
981 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
983 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
984 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
985 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
986 extern int blk_queue_dma_drain(struct request_queue *q,
987 dma_drain_needed_fn *dma_drain_needed,
988 void *buf, unsigned int size);
989 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
990 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
991 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
992 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
993 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
994 extern void blk_queue_dma_alignment(struct request_queue *, int);
995 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
996 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
997 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
998 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
999 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
1000 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1001 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1003 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1004 extern void blk_dump_rq_flags(struct request *, char *);
1005 extern long nr_blockdev_pages(void);
1007 bool __must_check blk_get_queue(struct request_queue *);
1008 struct request_queue *blk_alloc_queue(gfp_t);
1009 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1010 extern void blk_put_queue(struct request_queue *);
1011 extern void blk_set_queue_dying(struct request_queue *);
1014 * block layer runtime pm functions
1017 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1018 extern int blk_pre_runtime_suspend(struct request_queue *q);
1019 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1020 extern void blk_pre_runtime_resume(struct request_queue *q);
1021 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1023 static inline void blk_pm_runtime_init(struct request_queue *q,
1024 struct device *dev) {}
1025 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1029 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1030 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1031 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1035 * blk_plug permits building a queue of related requests by holding the I/O
1036 * fragments for a short period. This allows merging of sequential requests
1037 * into single larger request. As the requests are moved from a per-task list to
1038 * the device's request_queue in a batch, this results in improved scalability
1039 * as the lock contention for request_queue lock is reduced.
1041 * It is ok not to disable preemption when adding the request to the plug list
1042 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1043 * the plug list when the task sleeps by itself. For details, please see
1044 * schedule() where blk_schedule_flush_plug() is called.
1047 struct list_head list; /* requests */
1048 struct list_head mq_list; /* blk-mq requests */
1049 struct list_head cb_list; /* md requires an unplug callback */
1051 #define BLK_MAX_REQUEST_COUNT 16
1054 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1055 struct blk_plug_cb {
1056 struct list_head list;
1057 blk_plug_cb_fn callback;
1060 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1061 void *data, int size);
1062 extern void blk_start_plug(struct blk_plug *);
1063 extern void blk_finish_plug(struct blk_plug *);
1064 extern void blk_flush_plug_list(struct blk_plug *, bool);
1066 static inline void blk_flush_plug(struct task_struct *tsk)
1068 struct blk_plug *plug = tsk->plug;
1071 blk_flush_plug_list(plug, false);
1074 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1076 struct blk_plug *plug = tsk->plug;
1079 blk_flush_plug_list(plug, true);
1082 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1084 struct blk_plug *plug = tsk->plug;
1087 (!list_empty(&plug->list) ||
1088 !list_empty(&plug->mq_list) ||
1089 !list_empty(&plug->cb_list));
1095 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1096 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1097 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1098 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1099 extern void blk_queue_free_tags(struct request_queue *);
1100 extern int blk_queue_resize_tags(struct request_queue *, int);
1101 extern void blk_queue_invalidate_tags(struct request_queue *);
1102 extern struct blk_queue_tag *blk_init_tags(int, int);
1103 extern void blk_free_tags(struct blk_queue_tag *);
1105 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1108 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1110 return bqt->tag_index[tag];
1113 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1115 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1116 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1117 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1118 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1119 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1120 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1121 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1122 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1123 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1125 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1126 nr_blocks << (sb->s_blocksize_bits - 9),
1129 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1130 sector_t nr_blocks, gfp_t gfp_mask)
1132 return blkdev_issue_zeroout(sb->s_bdev,
1133 block << (sb->s_blocksize_bits - 9),
1134 nr_blocks << (sb->s_blocksize_bits - 9),
1138 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1140 enum blk_default_limits {
1141 BLK_MAX_SEGMENTS = 128,
1142 BLK_SAFE_MAX_SECTORS = 255,
1143 BLK_DEF_MAX_SECTORS = 2560,
1144 BLK_MAX_SEGMENT_SIZE = 65536,
1145 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1148 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1150 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1152 return q->limits.bounce_pfn;
1155 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1157 return q->limits.seg_boundary_mask;
1160 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1162 return q->limits.virt_boundary_mask;
1165 static inline unsigned int queue_max_sectors(struct request_queue *q)
1167 return q->limits.max_sectors;
1170 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1172 return q->limits.max_hw_sectors;
1175 static inline unsigned short queue_max_segments(struct request_queue *q)
1177 return q->limits.max_segments;
1180 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1182 return q->limits.max_segment_size;
1185 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1189 if (q && q->limits.logical_block_size)
1190 retval = q->limits.logical_block_size;
1195 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1197 return queue_logical_block_size(bdev_get_queue(bdev));
1200 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1202 return q->limits.physical_block_size;
1205 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1207 return queue_physical_block_size(bdev_get_queue(bdev));
1210 static inline unsigned int queue_io_min(struct request_queue *q)
1212 return q->limits.io_min;
1215 static inline int bdev_io_min(struct block_device *bdev)
1217 return queue_io_min(bdev_get_queue(bdev));
1220 static inline unsigned int queue_io_opt(struct request_queue *q)
1222 return q->limits.io_opt;
1225 static inline int bdev_io_opt(struct block_device *bdev)
1227 return queue_io_opt(bdev_get_queue(bdev));
1230 static inline int queue_alignment_offset(struct request_queue *q)
1232 if (q->limits.misaligned)
1235 return q->limits.alignment_offset;
1238 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1240 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1241 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1243 return (granularity + lim->alignment_offset - alignment) % granularity;
1246 static inline int bdev_alignment_offset(struct block_device *bdev)
1248 struct request_queue *q = bdev_get_queue(bdev);
1250 if (q->limits.misaligned)
1253 if (bdev != bdev->bd_contains)
1254 return bdev->bd_part->alignment_offset;
1256 return q->limits.alignment_offset;
1259 static inline int queue_discard_alignment(struct request_queue *q)
1261 if (q->limits.discard_misaligned)
1264 return q->limits.discard_alignment;
1267 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1269 unsigned int alignment, granularity, offset;
1271 if (!lim->max_discard_sectors)
1274 /* Why are these in bytes, not sectors? */
1275 alignment = lim->discard_alignment >> 9;
1276 granularity = lim->discard_granularity >> 9;
1280 /* Offset of the partition start in 'granularity' sectors */
1281 offset = sector_div(sector, granularity);
1283 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1284 offset = (granularity + alignment - offset) % granularity;
1286 /* Turn it back into bytes, gaah */
1290 static inline int bdev_discard_alignment(struct block_device *bdev)
1292 struct request_queue *q = bdev_get_queue(bdev);
1294 if (bdev != bdev->bd_contains)
1295 return bdev->bd_part->discard_alignment;
1297 return q->limits.discard_alignment;
1300 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1302 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1308 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1310 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1313 static inline unsigned int bdev_write_same(struct block_device *bdev)
1315 struct request_queue *q = bdev_get_queue(bdev);
1318 return q->limits.max_write_same_sectors;
1323 static inline int queue_dma_alignment(struct request_queue *q)
1325 return q ? q->dma_alignment : 511;
1328 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1331 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1332 return !(addr & alignment) && !(len & alignment);
1335 /* assumes size > 256 */
1336 static inline unsigned int blksize_bits(unsigned int size)
1338 unsigned int bits = 8;
1342 } while (size > 256);
1346 static inline unsigned int block_size(struct block_device *bdev)
1348 return bdev->bd_block_size;
1351 static inline bool queue_flush_queueable(struct request_queue *q)
1353 return !q->flush_not_queueable;
1356 typedef struct {struct page *v;} Sector;
1358 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1360 static inline void put_dev_sector(Sector p)
1362 page_cache_release(p.v);
1366 * Check if adding a bio_vec after bprv with offset would create a gap in
1367 * the SG list. Most drivers don't care about this, but some do.
1369 static inline bool bvec_gap_to_prev(struct request_queue *q,
1370 struct bio_vec *bprv, unsigned int offset)
1372 if (!queue_virt_boundary(q))
1375 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1378 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1381 if (!bio_has_data(prev))
1384 return bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1],
1385 next->bi_io_vec[0].bv_offset);
1388 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1390 return bio_will_gap(req->q, req->biotail, bio);
1393 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1395 return bio_will_gap(req->q, bio, req->bio);
1399 int kblockd_schedule_work(struct work_struct *work);
1400 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1401 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1403 #ifdef CONFIG_BLK_CGROUP
1405 * This should not be using sched_clock(). A real patch is in progress
1406 * to fix this up, until that is in place we need to disable preemption
1407 * around sched_clock() in this function and set_io_start_time_ns().
1409 static inline void set_start_time_ns(struct request *req)
1412 req->start_time_ns = sched_clock();
1416 static inline void set_io_start_time_ns(struct request *req)
1419 req->io_start_time_ns = sched_clock();
1423 static inline uint64_t rq_start_time_ns(struct request *req)
1425 return req->start_time_ns;
1428 static inline uint64_t rq_io_start_time_ns(struct request *req)
1430 return req->io_start_time_ns;
1433 static inline void set_start_time_ns(struct request *req) {}
1434 static inline void set_io_start_time_ns(struct request *req) {}
1435 static inline uint64_t rq_start_time_ns(struct request *req)
1439 static inline uint64_t rq_io_start_time_ns(struct request *req)
1445 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1446 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1447 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1448 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1450 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1452 enum blk_integrity_flags {
1453 BLK_INTEGRITY_VERIFY = 1 << 0,
1454 BLK_INTEGRITY_GENERATE = 1 << 1,
1455 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1456 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1459 struct blk_integrity_iter {
1463 unsigned int data_size;
1464 unsigned short interval;
1465 const char *disk_name;
1468 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1470 struct blk_integrity_profile {
1471 integrity_processing_fn *generate_fn;
1472 integrity_processing_fn *verify_fn;
1476 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1477 extern void blk_integrity_unregister(struct gendisk *);
1478 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1479 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1480 struct scatterlist *);
1481 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1482 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1484 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1487 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1489 struct blk_integrity *bi = &disk->queue->integrity;
1498 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1500 return blk_get_integrity(bdev->bd_disk);
1503 static inline bool blk_integrity_rq(struct request *rq)
1505 return rq->cmd_flags & REQ_INTEGRITY;
1508 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1511 q->limits.max_integrity_segments = segs;
1514 static inline unsigned short
1515 queue_max_integrity_segments(struct request_queue *q)
1517 return q->limits.max_integrity_segments;
1520 static inline bool integrity_req_gap_back_merge(struct request *req,
1523 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1524 struct bio_integrity_payload *bip_next = bio_integrity(next);
1526 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1527 bip_next->bip_vec[0].bv_offset);
1530 static inline bool integrity_req_gap_front_merge(struct request *req,
1533 struct bio_integrity_payload *bip = bio_integrity(bio);
1534 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1536 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1537 bip_next->bip_vec[0].bv_offset);
1540 #else /* CONFIG_BLK_DEV_INTEGRITY */
1543 struct block_device;
1545 struct blk_integrity;
1547 static inline int blk_integrity_rq(struct request *rq)
1551 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1556 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1558 struct scatterlist *s)
1562 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1566 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1570 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1574 static inline void blk_integrity_register(struct gendisk *d,
1575 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,
1602 static inline bool integrity_req_gap_back_merge(struct request *req,
1607 static inline bool integrity_req_gap_front_merge(struct request *req,
1613 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1615 struct block_device_operations {
1616 int (*open) (struct block_device *, fmode_t);
1617 void (*release) (struct gendisk *, fmode_t);
1618 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1619 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1620 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1621 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
1622 unsigned long *pfn);
1623 unsigned int (*check_events) (struct gendisk *disk,
1624 unsigned int clearing);
1625 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1626 int (*media_changed) (struct gendisk *);
1627 void (*unlock_native_capacity) (struct gendisk *);
1628 int (*revalidate_disk) (struct gendisk *);
1629 int (*getgeo)(struct block_device *, struct hd_geometry *);
1630 /* this callback is with swap_lock and sometimes page table lock held */
1631 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1632 struct module *owner;
1633 const struct pr_ops *pr_ops;
1636 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1638 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1639 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1640 struct writeback_control *);
1641 extern long bdev_direct_access(struct block_device *, sector_t,
1642 void __pmem **addr, unsigned long *pfn, long size);
1643 #else /* CONFIG_BLOCK */
1645 struct block_device;
1648 * stubs for when the block layer is configured out
1650 #define buffer_heads_over_limit 0
1652 static inline long nr_blockdev_pages(void)
1660 static inline void blk_start_plug(struct blk_plug *plug)
1664 static inline void blk_finish_plug(struct blk_plug *plug)
1668 static inline void blk_flush_plug(struct task_struct *task)
1672 static inline void blk_schedule_flush_plug(struct task_struct *task)
1677 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1682 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1683 sector_t *error_sector)
1688 #endif /* CONFIG_BLOCK */