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 bool blk_rq_is_passthrough(struct request *rq)
204 return rq->cmd_type != REQ_TYPE_FS;
207 static inline unsigned short req_get_ioprio(struct request *req)
212 #include <linux/elevator.h>
214 struct blk_queue_ctx;
216 typedef void (request_fn_proc) (struct request_queue *q);
217 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
218 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
219 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
222 typedef void (softirq_done_fn)(struct request *);
223 typedef int (dma_drain_needed_fn)(struct request *);
224 typedef int (lld_busy_fn) (struct request_queue *q);
225 typedef int (bsg_job_fn) (struct bsg_job *);
227 enum blk_eh_timer_return {
233 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
235 enum blk_queue_state {
240 struct blk_queue_tag {
241 struct request **tag_index; /* map of busy tags */
242 unsigned long *tag_map; /* bit map of free/busy tags */
243 int busy; /* current depth */
244 int max_depth; /* what we will send to device */
245 int real_max_depth; /* what the array can hold */
246 atomic_t refcnt; /* map can be shared */
247 int alloc_policy; /* tag allocation policy */
248 int next_tag; /* next tag */
250 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
251 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
253 #define BLK_SCSI_MAX_CMDS (256)
254 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
256 struct queue_limits {
257 unsigned long bounce_pfn;
258 unsigned long seg_boundary_mask;
259 unsigned long virt_boundary_mask;
261 unsigned int max_hw_sectors;
262 unsigned int max_dev_sectors;
263 unsigned int chunk_sectors;
264 unsigned int max_sectors;
265 unsigned int max_segment_size;
266 unsigned int physical_block_size;
267 unsigned int logical_block_size;
268 unsigned int alignment_offset;
271 unsigned int max_discard_sectors;
272 unsigned int max_hw_discard_sectors;
273 unsigned int max_write_same_sectors;
274 unsigned int discard_granularity;
275 unsigned int discard_alignment;
277 unsigned short max_segments;
278 unsigned short max_integrity_segments;
280 unsigned char misaligned;
281 unsigned char discard_misaligned;
282 unsigned char cluster;
283 unsigned char discard_zeroes_data;
284 unsigned char raid_partial_stripes_expensive;
287 struct request_queue {
289 * Together with queue_head for cacheline sharing
291 struct list_head queue_head;
292 struct request *last_merge;
293 struct elevator_queue *elevator;
294 int nr_rqs[2]; /* # allocated [a]sync rqs */
295 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
298 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
299 * is used, root blkg allocates from @q->root_rl and all other
300 * blkgs from their own blkg->rl. Which one to use should be
301 * determined using bio_request_list().
303 struct request_list root_rl;
305 request_fn_proc *request_fn;
306 make_request_fn *make_request_fn;
307 prep_rq_fn *prep_rq_fn;
308 unprep_rq_fn *unprep_rq_fn;
309 softirq_done_fn *softirq_done_fn;
310 rq_timed_out_fn *rq_timed_out_fn;
311 dma_drain_needed_fn *dma_drain_needed;
312 lld_busy_fn *lld_busy_fn;
314 struct blk_mq_ops *mq_ops;
316 unsigned int *mq_map;
319 struct blk_mq_ctx __percpu *queue_ctx;
320 unsigned int nr_queues;
322 /* hw dispatch queues */
323 struct blk_mq_hw_ctx **queue_hw_ctx;
324 unsigned int nr_hw_queues;
327 * Dispatch queue sorting
330 struct request *boundary_rq;
333 * Delayed queue handling
335 struct delayed_work delay_work;
337 struct backing_dev_info backing_dev_info;
340 * The queue owner gets to use this for whatever they like.
341 * ll_rw_blk doesn't touch it.
346 * various queue flags, see QUEUE_* below
348 unsigned long queue_flags;
351 * ida allocated id for this queue. Used to index queues from
357 * queue needs bounce pages for pages above this limit
362 * protects queue structures from reentrancy. ->__queue_lock should
363 * _never_ be used directly, it is queue private. always use
366 spinlock_t __queue_lock;
367 spinlock_t *queue_lock;
377 struct kobject mq_kobj;
379 #ifdef CONFIG_BLK_DEV_INTEGRITY
380 struct blk_integrity integrity;
381 #endif /* CONFIG_BLK_DEV_INTEGRITY */
386 unsigned int nr_pending;
392 unsigned long nr_requests; /* Max # of requests */
393 unsigned int nr_congestion_on;
394 unsigned int nr_congestion_off;
395 unsigned int nr_batching;
397 unsigned int dma_drain_size;
398 void *dma_drain_buffer;
399 unsigned int dma_pad_mask;
400 unsigned int dma_alignment;
402 struct blk_queue_tag *queue_tags;
403 struct list_head tag_busy_list;
405 unsigned int nr_sorted;
406 unsigned int in_flight[2];
408 * Number of active block driver functions for which blk_drain_queue()
409 * must wait. Must be incremented around functions that unlock the
410 * queue_lock internally, e.g. scsi_request_fn().
412 unsigned int request_fn_active;
414 unsigned int rq_timeout;
415 struct timer_list timeout;
416 struct list_head timeout_list;
418 struct list_head icq_list;
419 #ifdef CONFIG_BLK_CGROUP
420 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
421 struct blkcg_gq *root_blkg;
422 struct list_head blkg_list;
425 struct queue_limits limits;
430 unsigned int sg_timeout;
431 unsigned int sg_reserved_size;
433 #ifdef CONFIG_BLK_DEV_IO_TRACE
434 struct blk_trace __rcu *blk_trace;
435 struct mutex blk_trace_mutex;
438 * for flush operations
440 unsigned int flush_flags;
441 unsigned int flush_not_queueable:1;
442 struct blk_flush_queue *fq;
444 struct list_head requeue_list;
445 spinlock_t requeue_lock;
446 struct work_struct requeue_work;
448 struct mutex sysfs_lock;
451 atomic_t mq_freeze_depth;
453 #if defined(CONFIG_BLK_DEV_BSG)
454 bsg_job_fn *bsg_job_fn;
456 struct bsg_class_device bsg_dev;
459 #ifdef CONFIG_BLK_DEV_THROTTLING
461 struct throtl_data *td;
463 struct rcu_head rcu_head;
464 wait_queue_head_t mq_freeze_wq;
465 struct percpu_ref q_usage_counter;
466 struct list_head all_q_node;
468 struct blk_mq_tag_set *tag_set;
469 struct list_head tag_set_list;
470 struct bio_set *bio_split;
472 bool mq_sysfs_init_done;
475 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
476 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
477 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
478 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
479 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
480 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
481 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
482 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
483 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
484 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
485 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
486 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
487 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
488 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
489 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
490 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
491 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
492 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
493 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
494 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
495 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
496 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
497 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
499 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
500 (1 << QUEUE_FLAG_STACKABLE) | \
501 (1 << QUEUE_FLAG_SAME_COMP) | \
502 (1 << QUEUE_FLAG_ADD_RANDOM))
504 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
505 (1 << QUEUE_FLAG_STACKABLE) | \
506 (1 << QUEUE_FLAG_SAME_COMP))
508 static inline void queue_lockdep_assert_held(struct request_queue *q)
511 lockdep_assert_held(q->queue_lock);
514 static inline void queue_flag_set_unlocked(unsigned int flag,
515 struct request_queue *q)
517 __set_bit(flag, &q->queue_flags);
520 static inline int queue_flag_test_and_clear(unsigned int flag,
521 struct request_queue *q)
523 queue_lockdep_assert_held(q);
525 if (test_bit(flag, &q->queue_flags)) {
526 __clear_bit(flag, &q->queue_flags);
533 static inline int queue_flag_test_and_set(unsigned int flag,
534 struct request_queue *q)
536 queue_lockdep_assert_held(q);
538 if (!test_bit(flag, &q->queue_flags)) {
539 __set_bit(flag, &q->queue_flags);
546 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
548 queue_lockdep_assert_held(q);
549 __set_bit(flag, &q->queue_flags);
552 static inline void queue_flag_clear_unlocked(unsigned int flag,
553 struct request_queue *q)
555 __clear_bit(flag, &q->queue_flags);
558 static inline int queue_in_flight(struct request_queue *q)
560 return q->in_flight[0] + q->in_flight[1];
563 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
565 queue_lockdep_assert_held(q);
566 __clear_bit(flag, &q->queue_flags);
569 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
570 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
571 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
572 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
573 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
574 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
575 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
576 #define blk_queue_noxmerges(q) \
577 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
578 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
579 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
580 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
581 #define blk_queue_stackable(q) \
582 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
583 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
584 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
585 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
587 #define blk_noretry_request(rq) \
588 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
589 REQ_FAILFAST_DRIVER))
591 static inline bool blk_account_rq(struct request *rq)
593 return (rq->cmd_flags & REQ_STARTED) && !blk_rq_is_passthrough(rq);
596 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
597 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
598 /* rq->queuelist of dequeued request must be list_empty() */
599 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
601 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
603 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1))
606 * Driver can handle struct request, if it either has an old style
607 * request_fn defined, or is blk-mq based.
609 static inline bool queue_is_rq_based(struct request_queue *q)
611 return q->request_fn || q->mq_ops;
614 static inline unsigned int blk_queue_cluster(struct request_queue *q)
616 return q->limits.cluster;
620 * We regard a request as sync, if either a read or a sync write
622 static inline bool rw_is_sync(unsigned int rw_flags)
624 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
627 static inline bool rq_is_sync(struct request *rq)
629 return rw_is_sync(rq->cmd_flags);
632 static inline bool blk_rl_full(struct request_list *rl, bool sync)
634 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
636 return rl->flags & flag;
639 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
641 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
646 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
648 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
653 static inline bool rq_mergeable(struct request *rq)
655 if (blk_rq_is_passthrough(rq))
658 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
664 static inline bool blk_check_merge_flags(unsigned int flags1,
667 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
670 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
673 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
679 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
681 if (bio_data(a) == bio_data(b))
688 * q->prep_rq_fn return values
690 #define BLKPREP_OK 0 /* serve it */
691 #define BLKPREP_KILL 1 /* fatal error, kill */
692 #define BLKPREP_DEFER 2 /* leave on queue */
694 extern unsigned long blk_max_low_pfn, blk_max_pfn;
697 * standard bounce addresses:
699 * BLK_BOUNCE_HIGH : bounce all highmem pages
700 * BLK_BOUNCE_ANY : don't bounce anything
701 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
704 #if BITS_PER_LONG == 32
705 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
707 #define BLK_BOUNCE_HIGH -1ULL
709 #define BLK_BOUNCE_ANY (-1ULL)
710 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
713 * default timeout for SG_IO if none specified
715 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
716 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
719 extern int init_emergency_isa_pool(void);
720 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
722 static inline int init_emergency_isa_pool(void)
726 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
729 #endif /* CONFIG_MMU */
735 unsigned long offset;
740 struct req_iterator {
741 struct bvec_iter iter;
745 /* This should not be used directly - use rq_for_each_segment */
746 #define for_each_bio(_bio) \
747 for (; _bio; _bio = _bio->bi_next)
748 #define __rq_for_each_bio(_bio, rq) \
750 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
752 #define rq_for_each_segment(bvl, _rq, _iter) \
753 __rq_for_each_bio(_iter.bio, _rq) \
754 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
756 #define rq_iter_last(bvec, _iter) \
757 (_iter.bio->bi_next == NULL && \
758 bio_iter_last(bvec, _iter.iter))
760 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
761 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
763 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
764 extern void rq_flush_dcache_pages(struct request *rq);
766 static inline void rq_flush_dcache_pages(struct request *rq)
771 extern int blk_register_queue(struct gendisk *disk);
772 extern void blk_unregister_queue(struct gendisk *disk);
773 extern blk_qc_t generic_make_request(struct bio *bio);
774 extern void blk_rq_init(struct request_queue *q, struct request *rq);
775 extern void blk_put_request(struct request *);
776 extern void __blk_put_request(struct request_queue *, struct request *);
777 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
778 extern struct request *blk_make_request(struct request_queue *, struct bio *,
780 extern void blk_rq_set_block_pc(struct request *);
781 extern void blk_requeue_request(struct request_queue *, struct request *);
782 extern void blk_add_request_payload(struct request *rq, struct page *page,
784 extern int blk_lld_busy(struct request_queue *q);
785 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
786 struct bio_set *bs, gfp_t gfp_mask,
787 int (*bio_ctr)(struct bio *, struct bio *, void *),
789 extern void blk_rq_unprep_clone(struct request *rq);
790 extern int blk_insert_cloned_request(struct request_queue *q,
792 extern void blk_delay_queue(struct request_queue *, unsigned long);
793 extern void blk_queue_split(struct request_queue *, struct bio **,
795 extern void blk_recount_segments(struct request_queue *, struct bio *);
796 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
797 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
798 unsigned int, void __user *);
799 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
800 unsigned int, void __user *);
801 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
802 struct scsi_ioctl_command __user *);
804 extern int blk_queue_enter(struct request_queue *q, gfp_t gfp);
805 extern void blk_queue_exit(struct request_queue *q);
806 extern void blk_start_queue(struct request_queue *q);
807 extern void blk_start_queue_async(struct request_queue *q);
808 extern void blk_stop_queue(struct request_queue *q);
809 extern void blk_sync_queue(struct request_queue *q);
810 extern void __blk_stop_queue(struct request_queue *q);
811 extern void __blk_run_queue(struct request_queue *q);
812 extern void __blk_run_queue_uncond(struct request_queue *q);
813 extern void blk_run_queue(struct request_queue *);
814 extern void blk_run_queue_async(struct request_queue *q);
815 extern int blk_rq_map_user(struct request_queue *, struct request *,
816 struct rq_map_data *, void __user *, unsigned long,
818 extern int blk_rq_unmap_user(struct bio *);
819 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
820 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
821 struct rq_map_data *, const struct iov_iter *,
823 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
824 struct request *, int);
825 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
826 struct request *, int, rq_end_io_fn *);
828 bool blk_poll(struct request_queue *q, blk_qc_t cookie);
830 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
832 return bdev->bd_disk->queue; /* this is never NULL */
836 * The basic unit of block I/O is a sector. It is used in a number of contexts
837 * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
838 * bytes. Variables of type sector_t represent an offset or size that is a
839 * multiple of 512 bytes. Hence these two constants.
842 #define SECTOR_SHIFT 9
845 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
849 * blk_rq_pos() : the current sector
850 * blk_rq_bytes() : bytes left in the entire request
851 * blk_rq_cur_bytes() : bytes left in the current segment
852 * blk_rq_err_bytes() : bytes left till the next error boundary
853 * blk_rq_sectors() : sectors left in the entire request
854 * blk_rq_cur_sectors() : sectors left in the current segment
856 static inline sector_t blk_rq_pos(const struct request *rq)
861 static inline unsigned int blk_rq_bytes(const struct request *rq)
863 return rq->__data_len;
866 static inline int blk_rq_cur_bytes(const struct request *rq)
868 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
871 extern unsigned int blk_rq_err_bytes(const struct request *rq);
873 static inline unsigned int blk_rq_sectors(const struct request *rq)
875 return blk_rq_bytes(rq) >> SECTOR_SHIFT;
878 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
880 return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
883 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
884 unsigned int cmd_flags)
886 if (unlikely(cmd_flags & REQ_DISCARD))
887 return min(q->limits.max_discard_sectors,
888 UINT_MAX >> SECTOR_SHIFT);
890 if (unlikely(cmd_flags & REQ_WRITE_SAME))
891 return q->limits.max_write_same_sectors;
893 return q->limits.max_sectors;
897 * Return maximum size of a request at given offset. Only valid for
898 * file system requests.
900 static inline unsigned int blk_max_size_offset(struct request_queue *q,
903 if (!q->limits.chunk_sectors)
904 return q->limits.max_sectors;
906 return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
907 (offset & (q->limits.chunk_sectors - 1))));
910 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
912 struct request_queue *q = rq->q;
914 if (blk_rq_is_passthrough(rq))
915 return q->limits.max_hw_sectors;
917 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD))
918 return blk_queue_get_max_sectors(q, rq->cmd_flags);
920 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
921 blk_queue_get_max_sectors(q, rq->cmd_flags));
924 static inline unsigned int blk_rq_count_bios(struct request *rq)
926 unsigned int nr_bios = 0;
929 __rq_for_each_bio(bio, rq)
936 * Request issue related functions.
938 extern struct request *blk_peek_request(struct request_queue *q);
939 extern void blk_start_request(struct request *rq);
940 extern struct request *blk_fetch_request(struct request_queue *q);
943 * Request completion related functions.
945 * blk_update_request() completes given number of bytes and updates
946 * the request without completing it.
948 * blk_end_request() and friends. __blk_end_request() must be called
949 * with the request queue spinlock acquired.
951 * Several drivers define their own end_request and call
952 * blk_end_request() for parts of the original function.
953 * This prevents code duplication in drivers.
955 extern bool blk_update_request(struct request *rq, int error,
956 unsigned int nr_bytes);
957 extern void blk_finish_request(struct request *rq, int error);
958 extern bool blk_end_request(struct request *rq, int error,
959 unsigned int nr_bytes);
960 extern void blk_end_request_all(struct request *rq, int error);
961 extern bool blk_end_request_cur(struct request *rq, int error);
962 extern bool blk_end_request_err(struct request *rq, int error);
963 extern bool __blk_end_request(struct request *rq, int error,
964 unsigned int nr_bytes);
965 extern void __blk_end_request_all(struct request *rq, int error);
966 extern bool __blk_end_request_cur(struct request *rq, int error);
967 extern bool __blk_end_request_err(struct request *rq, int error);
969 extern void blk_complete_request(struct request *);
970 extern void __blk_complete_request(struct request *);
971 extern void blk_abort_request(struct request *);
972 extern void blk_unprep_request(struct request *);
975 * Access functions for manipulating queue properties
977 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
978 spinlock_t *lock, int node_id);
979 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
980 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
981 request_fn_proc *, spinlock_t *);
982 extern void blk_cleanup_queue(struct request_queue *);
983 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
984 extern void blk_queue_bounce_limit(struct request_queue *, u64);
985 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
986 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
987 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
988 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
989 extern void blk_queue_max_discard_sectors(struct request_queue *q,
990 unsigned int max_discard_sectors);
991 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
992 unsigned int max_write_same_sectors);
993 extern void blk_queue_logical_block_size(struct request_queue *, unsigned int);
994 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
995 extern void blk_queue_alignment_offset(struct request_queue *q,
996 unsigned int alignment);
997 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
998 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
999 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1000 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1001 extern void blk_set_default_limits(struct queue_limits *lim);
1002 extern void blk_set_stacking_limits(struct queue_limits *lim);
1003 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1005 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1007 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1009 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1010 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1011 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1012 extern int blk_queue_dma_drain(struct request_queue *q,
1013 dma_drain_needed_fn *dma_drain_needed,
1014 void *buf, unsigned int size);
1015 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1016 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1017 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1018 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1019 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1020 extern void blk_queue_dma_alignment(struct request_queue *, int);
1021 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1022 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1023 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1024 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1025 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
1026 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1027 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1029 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1030 extern void blk_dump_rq_flags(struct request *, char *);
1031 extern long nr_blockdev_pages(void);
1033 bool __must_check blk_get_queue(struct request_queue *);
1034 struct request_queue *blk_alloc_queue(gfp_t);
1035 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1036 extern void blk_put_queue(struct request_queue *);
1037 extern void blk_set_queue_dying(struct request_queue *);
1040 * block layer runtime pm functions
1043 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1044 extern int blk_pre_runtime_suspend(struct request_queue *q);
1045 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1046 extern void blk_pre_runtime_resume(struct request_queue *q);
1047 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1049 static inline void blk_pm_runtime_init(struct request_queue *q,
1050 struct device *dev) {}
1051 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1055 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1056 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1057 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1061 * blk_plug permits building a queue of related requests by holding the I/O
1062 * fragments for a short period. This allows merging of sequential requests
1063 * into single larger request. As the requests are moved from a per-task list to
1064 * the device's request_queue in a batch, this results in improved scalability
1065 * as the lock contention for request_queue lock is reduced.
1067 * It is ok not to disable preemption when adding the request to the plug list
1068 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1069 * the plug list when the task sleeps by itself. For details, please see
1070 * schedule() where blk_schedule_flush_plug() is called.
1073 struct list_head list; /* requests */
1074 struct list_head mq_list; /* blk-mq requests */
1075 struct list_head cb_list; /* md requires an unplug callback */
1077 #define BLK_MAX_REQUEST_COUNT 16
1080 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1081 struct blk_plug_cb {
1082 struct list_head list;
1083 blk_plug_cb_fn callback;
1086 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1087 void *data, int size);
1088 extern void blk_start_plug(struct blk_plug *);
1089 extern void blk_finish_plug(struct blk_plug *);
1090 extern void blk_flush_plug_list(struct blk_plug *, bool);
1092 static inline void blk_flush_plug(struct task_struct *tsk)
1094 struct blk_plug *plug = tsk->plug;
1097 blk_flush_plug_list(plug, false);
1100 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1102 struct blk_plug *plug = tsk->plug;
1105 blk_flush_plug_list(plug, true);
1108 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1110 struct blk_plug *plug = tsk->plug;
1113 (!list_empty(&plug->list) ||
1114 !list_empty(&plug->mq_list) ||
1115 !list_empty(&plug->cb_list));
1121 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1122 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1123 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1124 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1125 extern void blk_queue_free_tags(struct request_queue *);
1126 extern int blk_queue_resize_tags(struct request_queue *, int);
1127 extern void blk_queue_invalidate_tags(struct request_queue *);
1128 extern struct blk_queue_tag *blk_init_tags(int, int);
1129 extern void blk_free_tags(struct blk_queue_tag *);
1131 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1134 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1136 return bqt->tag_index[tag];
1139 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1141 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1142 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1143 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1144 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1145 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1146 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1147 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1148 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1149 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1151 return blkdev_issue_discard(sb->s_bdev,
1152 block << (sb->s_blocksize_bits -
1154 nr_blocks << (sb->s_blocksize_bits -
1158 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1159 sector_t nr_blocks, gfp_t gfp_mask)
1161 return blkdev_issue_zeroout(sb->s_bdev,
1162 block << (sb->s_blocksize_bits -
1164 nr_blocks << (sb->s_blocksize_bits -
1169 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1171 enum blk_default_limits {
1172 BLK_MAX_SEGMENTS = 128,
1173 BLK_SAFE_MAX_SECTORS = 255,
1174 BLK_DEF_MAX_SECTORS = 2560,
1175 BLK_MAX_SEGMENT_SIZE = 65536,
1176 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1179 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1181 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1183 return q->limits.bounce_pfn;
1186 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1188 return q->limits.seg_boundary_mask;
1191 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1193 return q->limits.virt_boundary_mask;
1196 static inline unsigned int queue_max_sectors(struct request_queue *q)
1198 return q->limits.max_sectors;
1201 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1203 return q->limits.max_hw_sectors;
1206 static inline unsigned short queue_max_segments(struct request_queue *q)
1208 return q->limits.max_segments;
1211 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1213 return q->limits.max_segment_size;
1216 static inline unsigned queue_logical_block_size(struct request_queue *q)
1220 if (q && q->limits.logical_block_size)
1221 retval = q->limits.logical_block_size;
1226 static inline unsigned int bdev_logical_block_size(struct block_device *bdev)
1228 return queue_logical_block_size(bdev_get_queue(bdev));
1231 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1233 return q->limits.physical_block_size;
1236 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1238 return queue_physical_block_size(bdev_get_queue(bdev));
1241 static inline unsigned int queue_io_min(struct request_queue *q)
1243 return q->limits.io_min;
1246 static inline int bdev_io_min(struct block_device *bdev)
1248 return queue_io_min(bdev_get_queue(bdev));
1251 static inline unsigned int queue_io_opt(struct request_queue *q)
1253 return q->limits.io_opt;
1256 static inline int bdev_io_opt(struct block_device *bdev)
1258 return queue_io_opt(bdev_get_queue(bdev));
1261 static inline int queue_alignment_offset(struct request_queue *q)
1263 if (q->limits.misaligned)
1266 return q->limits.alignment_offset;
1269 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1271 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1272 unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1275 return (granularity + lim->alignment_offset - alignment) % granularity;
1278 static inline int bdev_alignment_offset(struct block_device *bdev)
1280 struct request_queue *q = bdev_get_queue(bdev);
1282 if (q->limits.misaligned)
1285 if (bdev != bdev->bd_contains)
1286 return bdev->bd_part->alignment_offset;
1288 return q->limits.alignment_offset;
1291 static inline int queue_discard_alignment(struct request_queue *q)
1293 if (q->limits.discard_misaligned)
1296 return q->limits.discard_alignment;
1299 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1301 unsigned int alignment, granularity, offset;
1303 if (!lim->max_discard_sectors)
1306 /* Why are these in bytes, not sectors? */
1307 alignment = lim->discard_alignment >> SECTOR_SHIFT;
1308 granularity = lim->discard_granularity >> SECTOR_SHIFT;
1312 /* Offset of the partition start in 'granularity' sectors */
1313 offset = sector_div(sector, granularity);
1315 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1316 offset = (granularity + alignment - offset) % granularity;
1318 /* Turn it back into bytes, gaah */
1319 return offset << SECTOR_SHIFT;
1322 static inline int bdev_discard_alignment(struct block_device *bdev)
1324 struct request_queue *q = bdev_get_queue(bdev);
1326 if (bdev != bdev->bd_contains)
1327 return bdev->bd_part->discard_alignment;
1329 return q->limits.discard_alignment;
1332 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1334 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1340 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1342 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1345 static inline unsigned int bdev_write_same(struct block_device *bdev)
1347 struct request_queue *q = bdev_get_queue(bdev);
1350 return q->limits.max_write_same_sectors;
1355 static inline int queue_dma_alignment(struct request_queue *q)
1357 return q ? q->dma_alignment : 511;
1360 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1363 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1364 return !(addr & alignment) && !(len & alignment);
1367 /* assumes size > 256 */
1368 static inline unsigned int blksize_bits(unsigned int size)
1370 unsigned int bits = 8;
1374 } while (size > 256);
1378 static inline unsigned int block_size(struct block_device *bdev)
1380 return bdev->bd_block_size;
1383 static inline bool queue_flush_queueable(struct request_queue *q)
1385 return !q->flush_not_queueable;
1388 typedef struct {struct page *v;} Sector;
1390 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1392 static inline void put_dev_sector(Sector p)
1394 page_cache_release(p.v);
1397 static inline bool __bvec_gap_to_prev(struct request_queue *q,
1398 struct bio_vec *bprv, unsigned int offset)
1401 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1405 * Check if adding a bio_vec after bprv with offset would create a gap in
1406 * the SG list. Most drivers don't care about this, but some do.
1408 static inline bool bvec_gap_to_prev(struct request_queue *q,
1409 struct bio_vec *bprv, unsigned int offset)
1411 if (!queue_virt_boundary(q))
1413 return __bvec_gap_to_prev(q, bprv, offset);
1416 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1419 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1420 struct bio_vec pb, nb;
1422 bio_get_last_bvec(prev, &pb);
1423 bio_get_first_bvec(next, &nb);
1425 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1431 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1433 return bio_will_gap(req->q, req->biotail, bio);
1436 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1438 return bio_will_gap(req->q, bio, req->bio);
1442 int kblockd_schedule_work(struct work_struct *work);
1443 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1444 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1446 #ifdef CONFIG_BLK_CGROUP
1448 * This should not be using sched_clock(). A real patch is in progress
1449 * to fix this up, until that is in place we need to disable preemption
1450 * around sched_clock() in this function and set_io_start_time_ns().
1452 static inline void set_start_time_ns(struct request *req)
1455 req->start_time_ns = sched_clock();
1459 static inline void set_io_start_time_ns(struct request *req)
1462 req->io_start_time_ns = sched_clock();
1466 static inline uint64_t rq_start_time_ns(struct request *req)
1468 return req->start_time_ns;
1471 static inline uint64_t rq_io_start_time_ns(struct request *req)
1473 return req->io_start_time_ns;
1476 static inline void set_start_time_ns(struct request *req) {}
1477 static inline void set_io_start_time_ns(struct request *req) {}
1478 static inline uint64_t rq_start_time_ns(struct request *req)
1482 static inline uint64_t rq_io_start_time_ns(struct request *req)
1488 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1489 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1490 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1491 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1493 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1495 enum blk_integrity_flags {
1496 BLK_INTEGRITY_VERIFY = 1 << 0,
1497 BLK_INTEGRITY_GENERATE = 1 << 1,
1498 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1499 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1502 struct blk_integrity_iter {
1506 unsigned int data_size;
1507 unsigned short interval;
1508 const char *disk_name;
1511 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1513 struct blk_integrity_profile {
1514 integrity_processing_fn *generate_fn;
1515 integrity_processing_fn *verify_fn;
1519 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1520 extern void blk_integrity_unregister(struct gendisk *);
1521 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1522 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1523 struct scatterlist *);
1524 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1525 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1527 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1530 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1532 struct blk_integrity *bi = &disk->queue->integrity;
1541 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1543 return blk_get_integrity(bdev->bd_disk);
1546 static inline bool blk_integrity_rq(struct request *rq)
1548 return rq->cmd_flags & REQ_INTEGRITY;
1551 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1554 q->limits.max_integrity_segments = segs;
1557 static inline unsigned short
1558 queue_max_integrity_segments(struct request_queue *q)
1560 return q->limits.max_integrity_segments;
1563 static inline bool integrity_req_gap_back_merge(struct request *req,
1566 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1567 struct bio_integrity_payload *bip_next = bio_integrity(next);
1569 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1570 bip_next->bip_vec[0].bv_offset);
1573 static inline bool integrity_req_gap_front_merge(struct request *req,
1576 struct bio_integrity_payload *bip = bio_integrity(bio);
1577 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1579 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1580 bip_next->bip_vec[0].bv_offset);
1583 #else /* CONFIG_BLK_DEV_INTEGRITY */
1586 struct block_device;
1588 struct blk_integrity;
1590 static inline int blk_integrity_rq(struct request *rq)
1594 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1599 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1601 struct scatterlist *s)
1605 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1609 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1613 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1617 static inline void blk_integrity_register(struct gendisk *d,
1618 struct blk_integrity *b)
1621 static inline void blk_integrity_unregister(struct gendisk *d)
1624 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1628 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1632 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1638 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1645 static inline bool integrity_req_gap_back_merge(struct request *req,
1650 static inline bool integrity_req_gap_front_merge(struct request *req,
1656 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1658 struct block_device_operations {
1659 int (*open) (struct block_device *, fmode_t);
1660 void (*release) (struct gendisk *, fmode_t);
1661 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1662 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1663 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1664 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
1665 unsigned long *pfn);
1666 unsigned int (*check_events) (struct gendisk *disk,
1667 unsigned int clearing);
1668 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1669 int (*media_changed) (struct gendisk *);
1670 void (*unlock_native_capacity) (struct gendisk *);
1671 int (*revalidate_disk) (struct gendisk *);
1672 int (*getgeo)(struct block_device *, struct hd_geometry *);
1673 /* this callback is with swap_lock and sometimes page table lock held */
1674 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1675 struct module *owner;
1676 const struct pr_ops *pr_ops;
1679 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1681 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1682 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1683 struct writeback_control *);
1684 extern long bdev_direct_access(struct block_device *, sector_t,
1685 void __pmem **addr, unsigned long *pfn, long size);
1686 #else /* CONFIG_BLOCK */
1688 struct block_device;
1691 * stubs for when the block layer is configured out
1693 #define buffer_heads_over_limit 0
1695 static inline long nr_blockdev_pages(void)
1703 static inline void blk_start_plug(struct blk_plug *plug)
1707 static inline void blk_finish_plug(struct blk_plug *plug)
1711 static inline void blk_flush_plug(struct task_struct *task)
1715 static inline void blk_schedule_flush_plug(struct task_struct *task)
1720 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1725 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1726 sector_t *error_sector)
1731 #endif /* CONFIG_BLOCK */