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;
376 unsigned int nr_pending;
382 unsigned long nr_requests; /* Max # of requests */
383 unsigned int nr_congestion_on;
384 unsigned int nr_congestion_off;
385 unsigned int nr_batching;
387 unsigned int dma_drain_size;
388 void *dma_drain_buffer;
389 unsigned int dma_pad_mask;
390 unsigned int dma_alignment;
392 struct blk_queue_tag *queue_tags;
393 struct list_head tag_busy_list;
395 unsigned int nr_sorted;
396 unsigned int in_flight[2];
398 * Number of active block driver functions for which blk_drain_queue()
399 * must wait. Must be incremented around functions that unlock the
400 * queue_lock internally, e.g. scsi_request_fn().
402 unsigned int request_fn_active;
404 unsigned int rq_timeout;
405 struct timer_list timeout;
406 struct list_head timeout_list;
408 struct list_head icq_list;
409 #ifdef CONFIG_BLK_CGROUP
410 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
411 struct blkcg_gq *root_blkg;
412 struct list_head blkg_list;
415 struct queue_limits limits;
420 unsigned int sg_timeout;
421 unsigned int sg_reserved_size;
423 #ifdef CONFIG_BLK_DEV_IO_TRACE
424 struct blk_trace *blk_trace;
427 * for flush operations
429 unsigned int flush_flags;
430 unsigned int flush_not_queueable:1;
431 struct blk_flush_queue *fq;
433 struct list_head requeue_list;
434 spinlock_t requeue_lock;
435 struct work_struct requeue_work;
437 struct mutex sysfs_lock;
440 atomic_t mq_freeze_depth;
442 #if defined(CONFIG_BLK_DEV_BSG)
443 bsg_job_fn *bsg_job_fn;
445 struct bsg_class_device bsg_dev;
448 #ifdef CONFIG_BLK_DEV_THROTTLING
450 struct throtl_data *td;
452 struct rcu_head rcu_head;
453 wait_queue_head_t mq_freeze_wq;
454 struct percpu_ref mq_usage_counter;
455 struct list_head all_q_node;
457 struct blk_mq_tag_set *tag_set;
458 struct list_head tag_set_list;
459 struct bio_set *bio_split;
461 bool mq_sysfs_init_done;
464 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
465 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
466 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
467 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
468 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
469 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
470 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
471 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
472 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
473 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
474 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
475 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
476 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
477 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
478 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
479 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
480 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
481 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
482 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
483 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
484 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
485 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
487 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
488 (1 << QUEUE_FLAG_STACKABLE) | \
489 (1 << QUEUE_FLAG_SAME_COMP) | \
490 (1 << QUEUE_FLAG_ADD_RANDOM))
492 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
493 (1 << QUEUE_FLAG_STACKABLE) | \
494 (1 << QUEUE_FLAG_SAME_COMP))
496 static inline void queue_lockdep_assert_held(struct request_queue *q)
499 lockdep_assert_held(q->queue_lock);
502 static inline void queue_flag_set_unlocked(unsigned int flag,
503 struct request_queue *q)
505 __set_bit(flag, &q->queue_flags);
508 static inline int queue_flag_test_and_clear(unsigned int flag,
509 struct request_queue *q)
511 queue_lockdep_assert_held(q);
513 if (test_bit(flag, &q->queue_flags)) {
514 __clear_bit(flag, &q->queue_flags);
521 static inline int queue_flag_test_and_set(unsigned int flag,
522 struct request_queue *q)
524 queue_lockdep_assert_held(q);
526 if (!test_bit(flag, &q->queue_flags)) {
527 __set_bit(flag, &q->queue_flags);
534 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
536 queue_lockdep_assert_held(q);
537 __set_bit(flag, &q->queue_flags);
540 static inline void queue_flag_clear_unlocked(unsigned int flag,
541 struct request_queue *q)
543 __clear_bit(flag, &q->queue_flags);
546 static inline int queue_in_flight(struct request_queue *q)
548 return q->in_flight[0] + q->in_flight[1];
551 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
553 queue_lockdep_assert_held(q);
554 __clear_bit(flag, &q->queue_flags);
557 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
558 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
559 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
560 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
561 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
562 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
563 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
564 #define blk_queue_noxmerges(q) \
565 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
566 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
567 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
568 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
569 #define blk_queue_stackable(q) \
570 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
571 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
572 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
573 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
575 #define blk_noretry_request(rq) \
576 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
577 REQ_FAILFAST_DRIVER))
579 #define blk_account_rq(rq) \
580 (((rq)->cmd_flags & REQ_STARTED) && \
581 ((rq)->cmd_type == REQ_TYPE_FS))
583 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
584 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
585 /* rq->queuelist of dequeued request must be list_empty() */
586 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
588 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
590 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1))
593 * Driver can handle struct request, if it either has an old style
594 * request_fn defined, or is blk-mq based.
596 static inline bool queue_is_rq_based(struct request_queue *q)
598 return q->request_fn || q->mq_ops;
601 static inline unsigned int blk_queue_cluster(struct request_queue *q)
603 return q->limits.cluster;
607 * We regard a request as sync, if either a read or a sync write
609 static inline bool rw_is_sync(unsigned int rw_flags)
611 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
614 static inline bool rq_is_sync(struct request *rq)
616 return rw_is_sync(rq->cmd_flags);
619 static inline bool blk_rl_full(struct request_list *rl, bool sync)
621 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
623 return rl->flags & flag;
626 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
628 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
633 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
635 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
640 static inline bool rq_mergeable(struct request *rq)
642 if (rq->cmd_type != REQ_TYPE_FS)
645 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
651 static inline bool blk_check_merge_flags(unsigned int flags1,
654 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
657 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
660 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
666 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
668 if (bio_data(a) == bio_data(b))
675 * q->prep_rq_fn return values
677 #define BLKPREP_OK 0 /* serve it */
678 #define BLKPREP_KILL 1 /* fatal error, kill */
679 #define BLKPREP_DEFER 2 /* leave on queue */
681 extern unsigned long blk_max_low_pfn, blk_max_pfn;
684 * standard bounce addresses:
686 * BLK_BOUNCE_HIGH : bounce all highmem pages
687 * BLK_BOUNCE_ANY : don't bounce anything
688 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
691 #if BITS_PER_LONG == 32
692 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
694 #define BLK_BOUNCE_HIGH -1ULL
696 #define BLK_BOUNCE_ANY (-1ULL)
697 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
700 * default timeout for SG_IO if none specified
702 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
703 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
706 extern int init_emergency_isa_pool(void);
707 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
709 static inline int init_emergency_isa_pool(void)
713 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
716 #endif /* CONFIG_MMU */
722 unsigned long offset;
727 struct req_iterator {
728 struct bvec_iter iter;
732 /* This should not be used directly - use rq_for_each_segment */
733 #define for_each_bio(_bio) \
734 for (; _bio; _bio = _bio->bi_next)
735 #define __rq_for_each_bio(_bio, rq) \
737 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
739 #define rq_for_each_segment(bvl, _rq, _iter) \
740 __rq_for_each_bio(_iter.bio, _rq) \
741 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
743 #define rq_iter_last(bvec, _iter) \
744 (_iter.bio->bi_next == NULL && \
745 bio_iter_last(bvec, _iter.iter))
747 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
748 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
750 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
751 extern void rq_flush_dcache_pages(struct request *rq);
753 static inline void rq_flush_dcache_pages(struct request *rq)
758 extern int blk_register_queue(struct gendisk *disk);
759 extern void blk_unregister_queue(struct gendisk *disk);
760 extern void generic_make_request(struct bio *bio);
761 extern void blk_rq_init(struct request_queue *q, struct request *rq);
762 extern void blk_put_request(struct request *);
763 extern void __blk_put_request(struct request_queue *, struct request *);
764 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
765 extern struct request *blk_make_request(struct request_queue *, struct bio *,
767 extern void blk_rq_set_block_pc(struct request *);
768 extern void blk_requeue_request(struct request_queue *, struct request *);
769 extern void blk_add_request_payload(struct request *rq, struct page *page,
771 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
772 extern int blk_lld_busy(struct request_queue *q);
773 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
774 struct bio_set *bs, gfp_t gfp_mask,
775 int (*bio_ctr)(struct bio *, struct bio *, void *),
777 extern void blk_rq_unprep_clone(struct request *rq);
778 extern int blk_insert_cloned_request(struct request_queue *q,
780 extern void blk_delay_queue(struct request_queue *, unsigned long);
781 extern void blk_queue_split(struct request_queue *, struct bio **,
783 extern void blk_recount_segments(struct request_queue *, struct bio *);
784 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
785 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
786 unsigned int, void __user *);
787 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
788 unsigned int, void __user *);
789 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
790 struct scsi_ioctl_command __user *);
792 extern void blk_start_queue(struct request_queue *q);
793 extern void blk_stop_queue(struct request_queue *q);
794 extern void blk_sync_queue(struct request_queue *q);
795 extern void __blk_stop_queue(struct request_queue *q);
796 extern void __blk_run_queue(struct request_queue *q);
797 extern void __blk_run_queue_uncond(struct request_queue *q);
798 extern void blk_run_queue(struct request_queue *);
799 extern void blk_run_queue_async(struct request_queue *q);
800 extern int blk_rq_map_user(struct request_queue *, struct request *,
801 struct rq_map_data *, void __user *, unsigned long,
803 extern int blk_rq_unmap_user(struct bio *);
804 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
805 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
806 struct rq_map_data *, const struct iov_iter *,
808 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
809 struct request *, int);
810 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
811 struct request *, int, rq_end_io_fn *);
813 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
815 return bdev->bd_disk->queue; /* this is never NULL */
819 * blk_rq_pos() : the current sector
820 * blk_rq_bytes() : bytes left in the entire request
821 * blk_rq_cur_bytes() : bytes left in the current segment
822 * blk_rq_err_bytes() : bytes left till the next error boundary
823 * blk_rq_sectors() : sectors left in the entire request
824 * blk_rq_cur_sectors() : sectors left in the current segment
826 static inline sector_t blk_rq_pos(const struct request *rq)
831 static inline unsigned int blk_rq_bytes(const struct request *rq)
833 return rq->__data_len;
836 static inline int blk_rq_cur_bytes(const struct request *rq)
838 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
841 extern unsigned int blk_rq_err_bytes(const struct request *rq);
843 static inline unsigned int blk_rq_sectors(const struct request *rq)
845 return blk_rq_bytes(rq) >> 9;
848 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
850 return blk_rq_cur_bytes(rq) >> 9;
853 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
854 unsigned int cmd_flags)
856 if (unlikely(cmd_flags & REQ_DISCARD))
857 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
859 if (unlikely(cmd_flags & REQ_WRITE_SAME))
860 return q->limits.max_write_same_sectors;
862 return q->limits.max_sectors;
866 * Return maximum size of a request at given offset. Only valid for
867 * file system requests.
869 static inline unsigned int blk_max_size_offset(struct request_queue *q,
872 if (!q->limits.chunk_sectors)
873 return q->limits.max_sectors;
875 return q->limits.chunk_sectors -
876 (offset & (q->limits.chunk_sectors - 1));
879 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
881 struct request_queue *q = rq->q;
883 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
884 return q->limits.max_hw_sectors;
886 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD))
887 return blk_queue_get_max_sectors(q, rq->cmd_flags);
889 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
890 blk_queue_get_max_sectors(q, rq->cmd_flags));
893 static inline unsigned int blk_rq_count_bios(struct request *rq)
895 unsigned int nr_bios = 0;
898 __rq_for_each_bio(bio, rq)
905 * Request issue related functions.
907 extern struct request *blk_peek_request(struct request_queue *q);
908 extern void blk_start_request(struct request *rq);
909 extern struct request *blk_fetch_request(struct request_queue *q);
912 * Request completion related functions.
914 * blk_update_request() completes given number of bytes and updates
915 * the request without completing it.
917 * blk_end_request() and friends. __blk_end_request() must be called
918 * with the request queue spinlock acquired.
920 * Several drivers define their own end_request and call
921 * blk_end_request() for parts of the original function.
922 * This prevents code duplication in drivers.
924 extern bool blk_update_request(struct request *rq, int error,
925 unsigned int nr_bytes);
926 extern void blk_finish_request(struct request *rq, int error);
927 extern bool blk_end_request(struct request *rq, int error,
928 unsigned int nr_bytes);
929 extern void blk_end_request_all(struct request *rq, int error);
930 extern bool blk_end_request_cur(struct request *rq, int error);
931 extern bool blk_end_request_err(struct request *rq, int error);
932 extern bool __blk_end_request(struct request *rq, int error,
933 unsigned int nr_bytes);
934 extern void __blk_end_request_all(struct request *rq, int error);
935 extern bool __blk_end_request_cur(struct request *rq, int error);
936 extern bool __blk_end_request_err(struct request *rq, int error);
938 extern void blk_complete_request(struct request *);
939 extern void __blk_complete_request(struct request *);
940 extern void blk_abort_request(struct request *);
941 extern void blk_unprep_request(struct request *);
944 * Access functions for manipulating queue properties
946 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
947 spinlock_t *lock, int node_id);
948 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
949 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
950 request_fn_proc *, spinlock_t *);
951 extern void blk_cleanup_queue(struct request_queue *);
952 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
953 extern void blk_queue_bounce_limit(struct request_queue *, u64);
954 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
955 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
956 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
957 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
958 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
959 extern void blk_queue_max_discard_sectors(struct request_queue *q,
960 unsigned int max_discard_sectors);
961 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
962 unsigned int max_write_same_sectors);
963 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
964 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
965 extern void blk_queue_alignment_offset(struct request_queue *q,
966 unsigned int alignment);
967 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
968 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
969 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
970 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
971 extern void blk_set_default_limits(struct queue_limits *lim);
972 extern void blk_set_stacking_limits(struct queue_limits *lim);
973 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
975 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
977 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
979 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
980 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
981 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
982 extern int blk_queue_dma_drain(struct request_queue *q,
983 dma_drain_needed_fn *dma_drain_needed,
984 void *buf, unsigned int size);
985 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
986 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
987 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
988 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
989 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
990 extern void blk_queue_dma_alignment(struct request_queue *, int);
991 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
992 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
993 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
994 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
995 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
996 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
997 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
999 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1000 extern void blk_dump_rq_flags(struct request *, char *);
1001 extern long nr_blockdev_pages(void);
1003 bool __must_check blk_get_queue(struct request_queue *);
1004 struct request_queue *blk_alloc_queue(gfp_t);
1005 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1006 extern void blk_put_queue(struct request_queue *);
1007 extern void blk_set_queue_dying(struct request_queue *);
1010 * block layer runtime pm functions
1013 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1014 extern int blk_pre_runtime_suspend(struct request_queue *q);
1015 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1016 extern void blk_pre_runtime_resume(struct request_queue *q);
1017 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1019 static inline void blk_pm_runtime_init(struct request_queue *q,
1020 struct device *dev) {}
1021 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1025 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1026 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1027 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1031 * blk_plug permits building a queue of related requests by holding the I/O
1032 * fragments for a short period. This allows merging of sequential requests
1033 * into single larger request. As the requests are moved from a per-task list to
1034 * the device's request_queue in a batch, this results in improved scalability
1035 * as the lock contention for request_queue lock is reduced.
1037 * It is ok not to disable preemption when adding the request to the plug list
1038 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1039 * the plug list when the task sleeps by itself. For details, please see
1040 * schedule() where blk_schedule_flush_plug() is called.
1043 struct list_head list; /* requests */
1044 struct list_head mq_list; /* blk-mq requests */
1045 struct list_head cb_list; /* md requires an unplug callback */
1047 #define BLK_MAX_REQUEST_COUNT 16
1050 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1051 struct blk_plug_cb {
1052 struct list_head list;
1053 blk_plug_cb_fn callback;
1056 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1057 void *data, int size);
1058 extern void blk_start_plug(struct blk_plug *);
1059 extern void blk_finish_plug(struct blk_plug *);
1060 extern void blk_flush_plug_list(struct blk_plug *, bool);
1062 static inline void blk_flush_plug(struct task_struct *tsk)
1064 struct blk_plug *plug = tsk->plug;
1067 blk_flush_plug_list(plug, false);
1070 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1072 struct blk_plug *plug = tsk->plug;
1075 blk_flush_plug_list(plug, true);
1078 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1080 struct blk_plug *plug = tsk->plug;
1083 (!list_empty(&plug->list) ||
1084 !list_empty(&plug->mq_list) ||
1085 !list_empty(&plug->cb_list));
1091 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1092 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1093 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1094 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1095 extern void blk_queue_free_tags(struct request_queue *);
1096 extern int blk_queue_resize_tags(struct request_queue *, int);
1097 extern void blk_queue_invalidate_tags(struct request_queue *);
1098 extern struct blk_queue_tag *blk_init_tags(int, int);
1099 extern void blk_free_tags(struct blk_queue_tag *);
1101 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1104 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1106 return bqt->tag_index[tag];
1109 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1111 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1112 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1113 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1114 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1115 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1116 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1117 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1118 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1119 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1121 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1122 nr_blocks << (sb->s_blocksize_bits - 9),
1125 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1126 sector_t nr_blocks, gfp_t gfp_mask)
1128 return blkdev_issue_zeroout(sb->s_bdev,
1129 block << (sb->s_blocksize_bits - 9),
1130 nr_blocks << (sb->s_blocksize_bits - 9),
1134 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1136 enum blk_default_limits {
1137 BLK_MAX_SEGMENTS = 128,
1138 BLK_SAFE_MAX_SECTORS = 255,
1139 BLK_DEF_MAX_SECTORS = 2560,
1140 BLK_MAX_SEGMENT_SIZE = 65536,
1141 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1144 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1146 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1148 return q->limits.bounce_pfn;
1151 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1153 return q->limits.seg_boundary_mask;
1156 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1158 return q->limits.virt_boundary_mask;
1161 static inline unsigned int queue_max_sectors(struct request_queue *q)
1163 return q->limits.max_sectors;
1166 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1168 return q->limits.max_hw_sectors;
1171 static inline unsigned short queue_max_segments(struct request_queue *q)
1173 return q->limits.max_segments;
1176 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1178 return q->limits.max_segment_size;
1181 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1185 if (q && q->limits.logical_block_size)
1186 retval = q->limits.logical_block_size;
1191 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1193 return queue_logical_block_size(bdev_get_queue(bdev));
1196 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1198 return q->limits.physical_block_size;
1201 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1203 return queue_physical_block_size(bdev_get_queue(bdev));
1206 static inline unsigned int queue_io_min(struct request_queue *q)
1208 return q->limits.io_min;
1211 static inline int bdev_io_min(struct block_device *bdev)
1213 return queue_io_min(bdev_get_queue(bdev));
1216 static inline unsigned int queue_io_opt(struct request_queue *q)
1218 return q->limits.io_opt;
1221 static inline int bdev_io_opt(struct block_device *bdev)
1223 return queue_io_opt(bdev_get_queue(bdev));
1226 static inline int queue_alignment_offset(struct request_queue *q)
1228 if (q->limits.misaligned)
1231 return q->limits.alignment_offset;
1234 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1236 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1237 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1239 return (granularity + lim->alignment_offset - alignment) % granularity;
1242 static inline int bdev_alignment_offset(struct block_device *bdev)
1244 struct request_queue *q = bdev_get_queue(bdev);
1246 if (q->limits.misaligned)
1249 if (bdev != bdev->bd_contains)
1250 return bdev->bd_part->alignment_offset;
1252 return q->limits.alignment_offset;
1255 static inline int queue_discard_alignment(struct request_queue *q)
1257 if (q->limits.discard_misaligned)
1260 return q->limits.discard_alignment;
1263 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1265 unsigned int alignment, granularity, offset;
1267 if (!lim->max_discard_sectors)
1270 /* Why are these in bytes, not sectors? */
1271 alignment = lim->discard_alignment >> 9;
1272 granularity = lim->discard_granularity >> 9;
1276 /* Offset of the partition start in 'granularity' sectors */
1277 offset = sector_div(sector, granularity);
1279 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1280 offset = (granularity + alignment - offset) % granularity;
1282 /* Turn it back into bytes, gaah */
1286 static inline int bdev_discard_alignment(struct block_device *bdev)
1288 struct request_queue *q = bdev_get_queue(bdev);
1290 if (bdev != bdev->bd_contains)
1291 return bdev->bd_part->discard_alignment;
1293 return q->limits.discard_alignment;
1296 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1298 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1304 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1306 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1309 static inline unsigned int bdev_write_same(struct block_device *bdev)
1311 struct request_queue *q = bdev_get_queue(bdev);
1314 return q->limits.max_write_same_sectors;
1319 static inline int queue_dma_alignment(struct request_queue *q)
1321 return q ? q->dma_alignment : 511;
1324 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1327 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1328 return !(addr & alignment) && !(len & alignment);
1331 /* assumes size > 256 */
1332 static inline unsigned int blksize_bits(unsigned int size)
1334 unsigned int bits = 8;
1338 } while (size > 256);
1342 static inline unsigned int block_size(struct block_device *bdev)
1344 return bdev->bd_block_size;
1347 static inline bool queue_flush_queueable(struct request_queue *q)
1349 return !q->flush_not_queueable;
1352 typedef struct {struct page *v;} Sector;
1354 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1356 static inline void put_dev_sector(Sector p)
1358 page_cache_release(p.v);
1362 * Check if adding a bio_vec after bprv with offset would create a gap in
1363 * the SG list. Most drivers don't care about this, but some do.
1365 static inline bool bvec_gap_to_prev(struct request_queue *q,
1366 struct bio_vec *bprv, unsigned int offset)
1368 if (!queue_virt_boundary(q))
1371 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1374 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1377 if (!bio_has_data(prev))
1380 return bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1],
1381 next->bi_io_vec[0].bv_offset);
1384 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1386 return bio_will_gap(req->q, req->biotail, bio);
1389 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1391 return bio_will_gap(req->q, bio, req->bio);
1395 int kblockd_schedule_work(struct work_struct *work);
1396 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1397 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1399 #ifdef CONFIG_BLK_CGROUP
1401 * This should not be using sched_clock(). A real patch is in progress
1402 * to fix this up, until that is in place we need to disable preemption
1403 * around sched_clock() in this function and set_io_start_time_ns().
1405 static inline void set_start_time_ns(struct request *req)
1408 req->start_time_ns = sched_clock();
1412 static inline void set_io_start_time_ns(struct request *req)
1415 req->io_start_time_ns = sched_clock();
1419 static inline uint64_t rq_start_time_ns(struct request *req)
1421 return req->start_time_ns;
1424 static inline uint64_t rq_io_start_time_ns(struct request *req)
1426 return req->io_start_time_ns;
1429 static inline void set_start_time_ns(struct request *req) {}
1430 static inline void set_io_start_time_ns(struct request *req) {}
1431 static inline uint64_t rq_start_time_ns(struct request *req)
1435 static inline uint64_t rq_io_start_time_ns(struct request *req)
1441 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1442 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1443 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1444 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1446 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1448 enum blk_integrity_flags {
1449 BLK_INTEGRITY_VERIFY = 1 << 0,
1450 BLK_INTEGRITY_GENERATE = 1 << 1,
1451 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1452 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1455 struct blk_integrity_iter {
1459 unsigned int data_size;
1460 unsigned short interval;
1461 const char *disk_name;
1464 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1466 struct blk_integrity {
1467 integrity_processing_fn *generate_fn;
1468 integrity_processing_fn *verify_fn;
1470 unsigned short flags;
1471 unsigned short tuple_size;
1472 unsigned short interval;
1473 unsigned short tag_size;
1477 struct kobject kobj;
1480 extern bool blk_integrity_is_initialized(struct gendisk *);
1481 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1482 extern void blk_integrity_unregister(struct gendisk *);
1483 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1484 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1485 struct scatterlist *);
1486 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1487 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1489 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1493 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1495 return bdev->bd_disk->integrity;
1498 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1500 return disk->integrity;
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 int blk_integrity_register(struct gendisk *d,
1575 struct blk_integrity *b)
1579 static inline void blk_integrity_unregister(struct gendisk *d)
1582 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1586 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1590 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1596 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1602 static inline bool blk_integrity_is_initialized(struct gendisk *g)
1606 static inline bool integrity_req_gap_back_merge(struct request *req,
1611 static inline bool integrity_req_gap_front_merge(struct request *req,
1617 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1619 struct block_device_operations {
1620 int (*open) (struct block_device *, fmode_t);
1621 void (*release) (struct gendisk *, fmode_t);
1622 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1623 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1624 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1625 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
1626 unsigned long *pfn);
1627 unsigned int (*check_events) (struct gendisk *disk,
1628 unsigned int clearing);
1629 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1630 int (*media_changed) (struct gendisk *);
1631 void (*unlock_native_capacity) (struct gendisk *);
1632 int (*revalidate_disk) (struct gendisk *);
1633 int (*getgeo)(struct block_device *, struct hd_geometry *);
1634 /* this callback is with swap_lock and sometimes page table lock held */
1635 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1636 struct module *owner;
1637 const struct pr_ops *pr_ops;
1640 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1642 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1643 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1644 struct writeback_control *);
1645 extern long bdev_direct_access(struct block_device *, sector_t,
1646 void __pmem **addr, unsigned long *pfn, long size);
1647 #else /* CONFIG_BLOCK */
1649 struct block_device;
1652 * stubs for when the block layer is configured out
1654 #define buffer_heads_over_limit 0
1656 static inline long nr_blockdev_pages(void)
1664 static inline void blk_start_plug(struct blk_plug *plug)
1668 static inline void blk_finish_plug(struct blk_plug *plug)
1672 static inline void blk_flush_plug(struct task_struct *task)
1676 static inline void blk_schedule_flush_plug(struct task_struct *task)
1681 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1686 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1687 sector_t *error_sector)
1692 #endif /* CONFIG_BLOCK */