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;
201 ktime_t lat_hist_io_start;
202 int lat_hist_enabled;
205 static inline bool blk_rq_is_passthrough(struct request *rq)
207 return rq->cmd_type != REQ_TYPE_FS;
210 static inline unsigned short req_get_ioprio(struct request *req)
215 #include <linux/elevator.h>
217 struct blk_queue_ctx;
219 typedef void (request_fn_proc) (struct request_queue *q);
220 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
221 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
222 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
225 typedef void (softirq_done_fn)(struct request *);
226 typedef int (dma_drain_needed_fn)(struct request *);
227 typedef int (lld_busy_fn) (struct request_queue *q);
228 typedef int (bsg_job_fn) (struct bsg_job *);
230 enum blk_eh_timer_return {
236 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
238 enum blk_queue_state {
243 struct blk_queue_tag {
244 struct request **tag_index; /* map of busy tags */
245 unsigned long *tag_map; /* bit map of free/busy tags */
246 int busy; /* current depth */
247 int max_depth; /* what we will send to device */
248 int real_max_depth; /* what the array can hold */
249 atomic_t refcnt; /* map can be shared */
250 int alloc_policy; /* tag allocation policy */
251 int next_tag; /* next tag */
253 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
254 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
256 #define BLK_SCSI_MAX_CMDS (256)
257 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
259 struct queue_limits {
260 unsigned long bounce_pfn;
261 unsigned long seg_boundary_mask;
262 unsigned long virt_boundary_mask;
264 unsigned int max_hw_sectors;
265 unsigned int max_dev_sectors;
266 unsigned int chunk_sectors;
267 unsigned int max_sectors;
268 unsigned int max_segment_size;
269 unsigned int physical_block_size;
270 unsigned int alignment_offset;
273 unsigned int max_discard_sectors;
274 unsigned int max_hw_discard_sectors;
275 unsigned int max_write_same_sectors;
276 unsigned int discard_granularity;
277 unsigned int discard_alignment;
279 unsigned short logical_block_size;
280 unsigned short max_segments;
281 unsigned short max_integrity_segments;
283 unsigned char misaligned;
284 unsigned char discard_misaligned;
285 unsigned char cluster;
286 unsigned char discard_zeroes_data;
287 unsigned char raid_partial_stripes_expensive;
290 struct request_queue {
292 * Together with queue_head for cacheline sharing
294 struct list_head queue_head;
295 struct request *last_merge;
296 struct elevator_queue *elevator;
297 int nr_rqs[2]; /* # allocated [a]sync rqs */
298 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
301 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
302 * is used, root blkg allocates from @q->root_rl and all other
303 * blkgs from their own blkg->rl. Which one to use should be
304 * determined using bio_request_list().
306 struct request_list root_rl;
308 request_fn_proc *request_fn;
309 make_request_fn *make_request_fn;
310 prep_rq_fn *prep_rq_fn;
311 unprep_rq_fn *unprep_rq_fn;
312 softirq_done_fn *softirq_done_fn;
313 rq_timed_out_fn *rq_timed_out_fn;
314 dma_drain_needed_fn *dma_drain_needed;
315 lld_busy_fn *lld_busy_fn;
317 struct blk_mq_ops *mq_ops;
319 unsigned int *mq_map;
322 struct blk_mq_ctx __percpu *queue_ctx;
323 unsigned int nr_queues;
325 /* hw dispatch queues */
326 struct blk_mq_hw_ctx **queue_hw_ctx;
327 unsigned int nr_hw_queues;
330 * Dispatch queue sorting
333 struct request *boundary_rq;
336 * Delayed queue handling
338 struct delayed_work delay_work;
340 struct backing_dev_info *backing_dev_info;
343 * The queue owner gets to use this for whatever they like.
344 * ll_rw_blk doesn't touch it.
349 * various queue flags, see QUEUE_* below
351 unsigned long queue_flags;
354 * ida allocated id for this queue. Used to index queues from
360 * queue needs bounce pages for pages above this limit
365 * protects queue structures from reentrancy. ->__queue_lock should
366 * _never_ be used directly, it is queue private. always use
369 spinlock_t __queue_lock;
370 spinlock_t *queue_lock;
380 struct kobject mq_kobj;
382 #ifdef CONFIG_BLK_DEV_INTEGRITY
383 struct blk_integrity integrity;
384 #endif /* CONFIG_BLK_DEV_INTEGRITY */
389 unsigned int nr_pending;
395 unsigned long nr_requests; /* Max # of requests */
396 unsigned int nr_congestion_on;
397 unsigned int nr_congestion_off;
398 unsigned int nr_batching;
400 unsigned int dma_drain_size;
401 void *dma_drain_buffer;
402 unsigned int dma_pad_mask;
403 unsigned int dma_alignment;
405 struct blk_queue_tag *queue_tags;
406 struct list_head tag_busy_list;
408 unsigned int nr_sorted;
409 unsigned int in_flight[2];
411 * Number of active block driver functions for which blk_drain_queue()
412 * must wait. Must be incremented around functions that unlock the
413 * queue_lock internally, e.g. scsi_request_fn().
415 unsigned int request_fn_active;
417 unsigned int rq_timeout;
418 struct timer_list timeout;
419 struct list_head timeout_list;
421 struct list_head icq_list;
422 #ifdef CONFIG_BLK_CGROUP
423 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
424 struct blkcg_gq *root_blkg;
425 struct list_head blkg_list;
428 struct queue_limits limits;
433 unsigned int sg_timeout;
434 unsigned int sg_reserved_size;
436 #ifdef CONFIG_BLK_DEV_IO_TRACE
437 struct blk_trace *blk_trace;
440 * for flush operations
442 unsigned int flush_flags;
443 unsigned int flush_not_queueable:1;
444 struct blk_flush_queue *fq;
446 struct list_head requeue_list;
447 spinlock_t requeue_lock;
448 struct work_struct requeue_work;
450 struct mutex sysfs_lock;
453 atomic_t mq_freeze_depth;
455 #if defined(CONFIG_BLK_DEV_BSG)
456 bsg_job_fn *bsg_job_fn;
458 struct bsg_class_device bsg_dev;
461 #ifdef CONFIG_BLK_DEV_THROTTLING
463 struct throtl_data *td;
465 struct rcu_head rcu_head;
466 wait_queue_head_t mq_freeze_wq;
467 struct percpu_ref q_usage_counter;
468 struct list_head all_q_node;
470 struct blk_mq_tag_set *tag_set;
471 struct list_head tag_set_list;
472 struct bio_set *bio_split;
474 bool mq_sysfs_init_done;
477 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
478 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
479 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
480 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
481 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
482 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
483 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
484 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
485 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
486 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
487 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
488 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
489 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
490 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
491 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
492 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
493 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
494 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
495 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
496 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
497 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
498 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
499 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
500 #define QUEUE_FLAG_FAST 23 /* fast block device (e.g. ram based) */
502 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_STACKABLE) | \
503 (1 << QUEUE_FLAG_SAME_COMP))
505 #define QUEUE_FLAG_MQ_DEFAULT ((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))
586 #define blk_queue_fast(q) test_bit(QUEUE_FLAG_FAST, &(q)->queue_flags)
588 #define blk_noretry_request(rq) \
589 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
590 REQ_FAILFAST_DRIVER))
592 static inline bool blk_account_rq(struct request *rq)
594 return (rq->cmd_flags & REQ_STARTED) && !blk_rq_is_passthrough(rq);
597 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
598 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
599 /* rq->queuelist of dequeued request must be list_empty() */
600 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
602 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
604 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1))
607 * Driver can handle struct request, if it either has an old style
608 * request_fn defined, or is blk-mq based.
610 static inline bool queue_is_rq_based(struct request_queue *q)
612 return q->request_fn || q->mq_ops;
615 static inline unsigned int blk_queue_cluster(struct request_queue *q)
617 return q->limits.cluster;
621 * We regard a request as sync, if either a read or a sync write
623 static inline bool rw_is_sync(unsigned int rw_flags)
625 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
628 static inline bool rq_is_sync(struct request *rq)
630 return rw_is_sync(rq->cmd_flags);
633 static inline bool blk_rl_full(struct request_list *rl, bool sync)
635 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
637 return rl->flags & flag;
640 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
642 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
647 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
649 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
654 static inline bool rq_mergeable(struct request *rq)
656 if (blk_rq_is_passthrough(rq))
659 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
665 static inline bool blk_check_merge_flags(unsigned int flags1,
668 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
671 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
674 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
680 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
682 if (bio_data(a) == bio_data(b))
689 * q->prep_rq_fn return values
691 #define BLKPREP_OK 0 /* serve it */
692 #define BLKPREP_KILL 1 /* fatal error, kill */
693 #define BLKPREP_DEFER 2 /* leave on queue */
695 extern unsigned long blk_max_low_pfn, blk_max_pfn;
698 * standard bounce addresses:
700 * BLK_BOUNCE_HIGH : bounce all highmem pages
701 * BLK_BOUNCE_ANY : don't bounce anything
702 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
705 #if BITS_PER_LONG == 32
706 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
708 #define BLK_BOUNCE_HIGH -1ULL
710 #define BLK_BOUNCE_ANY (-1ULL)
711 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
714 * default timeout for SG_IO if none specified
716 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
717 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
720 extern int init_emergency_isa_pool(void);
721 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
723 static inline int init_emergency_isa_pool(void)
727 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
730 #endif /* CONFIG_MMU */
736 unsigned long offset;
741 struct req_iterator {
742 struct bvec_iter iter;
746 /* This should not be used directly - use rq_for_each_segment */
747 #define for_each_bio(_bio) \
748 for (; _bio; _bio = _bio->bi_next)
749 #define __rq_for_each_bio(_bio, rq) \
751 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
753 #define rq_for_each_segment(bvl, _rq, _iter) \
754 __rq_for_each_bio(_iter.bio, _rq) \
755 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
757 #define rq_iter_last(bvec, _iter) \
758 (_iter.bio->bi_next == NULL && \
759 bio_iter_last(bvec, _iter.iter))
761 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
762 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
764 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
765 extern void rq_flush_dcache_pages(struct request *rq);
767 static inline void rq_flush_dcache_pages(struct request *rq)
772 extern int blk_register_queue(struct gendisk *disk);
773 extern void blk_unregister_queue(struct gendisk *disk);
774 extern blk_qc_t generic_make_request(struct bio *bio);
775 extern void blk_rq_init(struct request_queue *q, struct request *rq);
776 extern void blk_put_request(struct request *);
777 extern void __blk_put_request(struct request_queue *, struct request *);
778 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
779 extern struct request *blk_make_request(struct request_queue *, struct bio *,
781 extern void blk_rq_set_block_pc(struct request *);
782 extern void blk_requeue_request(struct request_queue *, struct request *);
783 extern void blk_add_request_payload(struct request *rq, struct page *page,
785 extern int blk_lld_busy(struct request_queue *q);
786 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
787 struct bio_set *bs, gfp_t gfp_mask,
788 int (*bio_ctr)(struct bio *, struct bio *, void *),
790 extern void blk_rq_unprep_clone(struct request *rq);
791 extern int blk_insert_cloned_request(struct request_queue *q,
793 extern void blk_delay_queue(struct request_queue *, unsigned long);
794 extern void blk_queue_split(struct request_queue *, struct bio **,
796 extern void blk_recount_segments(struct request_queue *, struct bio *);
797 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
798 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
799 unsigned int, void __user *);
800 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
801 unsigned int, void __user *);
802 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
803 struct scsi_ioctl_command __user *);
805 extern void blk_recalc_rq_segments(struct request *rq);
806 extern int blk_queue_enter(struct request_queue *q, gfp_t gfp);
807 extern void blk_queue_exit(struct request_queue *q);
808 extern void blk_start_queue(struct request_queue *q);
809 extern void blk_start_queue_async(struct request_queue *q);
810 extern void blk_stop_queue(struct request_queue *q);
811 extern void blk_sync_queue(struct request_queue *q);
812 extern void __blk_stop_queue(struct request_queue *q);
813 extern void __blk_run_queue(struct request_queue *q);
814 extern void __blk_run_queue_uncond(struct request_queue *q);
815 extern void blk_run_queue(struct request_queue *);
816 extern void blk_run_queue_async(struct request_queue *q);
817 extern int blk_rq_map_user(struct request_queue *, struct request *,
818 struct rq_map_data *, void __user *, unsigned long,
820 extern int blk_rq_unmap_user(struct bio *);
821 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
822 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
823 struct rq_map_data *, const struct iov_iter *,
825 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
826 struct request *, int);
827 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
828 struct request *, int, rq_end_io_fn *);
830 bool blk_poll(struct request_queue *q, blk_qc_t cookie);
832 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
834 return bdev->bd_disk->queue; /* this is never NULL */
838 * blk_rq_pos() : the current sector
839 * blk_rq_bytes() : bytes left in the entire request
840 * blk_rq_cur_bytes() : bytes left in the current segment
841 * blk_rq_err_bytes() : bytes left till the next error boundary
842 * blk_rq_sectors() : sectors left in the entire request
843 * blk_rq_cur_sectors() : sectors left in the current segment
845 static inline sector_t blk_rq_pos(const struct request *rq)
850 static inline unsigned int blk_rq_bytes(const struct request *rq)
852 return rq->__data_len;
855 static inline int blk_rq_cur_bytes(const struct request *rq)
857 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
860 extern unsigned int blk_rq_err_bytes(const struct request *rq);
862 static inline unsigned int blk_rq_sectors(const struct request *rq)
864 return blk_rq_bytes(rq) >> 9;
867 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
869 return blk_rq_cur_bytes(rq) >> 9;
872 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
873 unsigned int cmd_flags)
875 if (unlikely(cmd_flags & REQ_DISCARD))
876 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
878 if (unlikely(cmd_flags & REQ_WRITE_SAME))
879 return q->limits.max_write_same_sectors;
881 return q->limits.max_sectors;
885 * Return maximum size of a request at given offset. Only valid for
886 * file system requests.
888 static inline unsigned int blk_max_size_offset(struct request_queue *q,
891 if (!q->limits.chunk_sectors)
892 return q->limits.max_sectors;
894 return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
895 (offset & (q->limits.chunk_sectors - 1))));
898 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
900 struct request_queue *q = rq->q;
902 if (blk_rq_is_passthrough(rq))
903 return q->limits.max_hw_sectors;
905 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD))
906 return blk_queue_get_max_sectors(q, rq->cmd_flags);
908 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
909 blk_queue_get_max_sectors(q, rq->cmd_flags));
912 static inline unsigned int blk_rq_count_bios(struct request *rq)
914 unsigned int nr_bios = 0;
917 __rq_for_each_bio(bio, rq)
924 * Request issue related functions.
926 extern struct request *blk_peek_request(struct request_queue *q);
927 extern void blk_start_request(struct request *rq);
928 extern struct request *blk_fetch_request(struct request_queue *q);
931 * Request completion related functions.
933 * blk_update_request() completes given number of bytes and updates
934 * the request without completing it.
936 * blk_end_request() and friends. __blk_end_request() must be called
937 * with the request queue spinlock acquired.
939 * Several drivers define their own end_request and call
940 * blk_end_request() for parts of the original function.
941 * This prevents code duplication in drivers.
943 extern bool blk_update_request(struct request *rq, int error,
944 unsigned int nr_bytes);
945 extern void blk_finish_request(struct request *rq, int error);
946 extern bool blk_end_request(struct request *rq, int error,
947 unsigned int nr_bytes);
948 extern void blk_end_request_all(struct request *rq, int error);
949 extern bool blk_end_request_cur(struct request *rq, int error);
950 extern bool blk_end_request_err(struct request *rq, int error);
951 extern bool __blk_end_request(struct request *rq, int error,
952 unsigned int nr_bytes);
953 extern void __blk_end_request_all(struct request *rq, int error);
954 extern bool __blk_end_request_cur(struct request *rq, int error);
955 extern bool __blk_end_request_err(struct request *rq, int error);
957 extern void blk_complete_request(struct request *);
958 extern void __blk_complete_request(struct request *);
959 extern void blk_abort_request(struct request *);
960 extern void blk_unprep_request(struct request *);
963 * Access functions for manipulating queue properties
965 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
966 spinlock_t *lock, int node_id);
967 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
968 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
969 request_fn_proc *, spinlock_t *);
970 extern void blk_cleanup_queue(struct request_queue *);
971 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
972 extern void blk_queue_bounce_limit(struct request_queue *, u64);
973 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
974 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
975 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
976 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
977 extern void blk_queue_max_discard_sectors(struct request_queue *q,
978 unsigned int max_discard_sectors);
979 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
980 unsigned int max_write_same_sectors);
981 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
982 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
983 extern void blk_queue_alignment_offset(struct request_queue *q,
984 unsigned int alignment);
985 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
986 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
987 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
988 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
989 extern void blk_set_default_limits(struct queue_limits *lim);
990 extern void blk_set_stacking_limits(struct queue_limits *lim);
991 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
993 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
995 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
997 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
998 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
999 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1000 extern int blk_queue_dma_drain(struct request_queue *q,
1001 dma_drain_needed_fn *dma_drain_needed,
1002 void *buf, unsigned int size);
1003 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1004 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1005 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1006 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1007 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1008 extern void blk_queue_dma_alignment(struct request_queue *, int);
1009 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1010 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1011 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1012 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1013 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
1014 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1015 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1017 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1018 extern int blk_rq_map_sg_no_cluster
1019 (struct request_queue *, struct request *, struct scatterlist *);
1020 extern void blk_dump_rq_flags(struct request *, char *);
1021 extern long nr_blockdev_pages(void);
1023 bool __must_check blk_get_queue(struct request_queue *);
1024 struct request_queue *blk_alloc_queue(gfp_t);
1025 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1026 extern void blk_put_queue(struct request_queue *);
1027 extern void blk_set_queue_dying(struct request_queue *);
1030 * block layer runtime pm functions
1033 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1034 extern int blk_pre_runtime_suspend(struct request_queue *q);
1035 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1036 extern void blk_pre_runtime_resume(struct request_queue *q);
1037 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1039 static inline void blk_pm_runtime_init(struct request_queue *q,
1040 struct device *dev) {}
1041 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1045 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1046 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1047 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1051 * blk_plug permits building a queue of related requests by holding the I/O
1052 * fragments for a short period. This allows merging of sequential requests
1053 * into single larger request. As the requests are moved from a per-task list to
1054 * the device's request_queue in a batch, this results in improved scalability
1055 * as the lock contention for request_queue lock is reduced.
1057 * It is ok not to disable preemption when adding the request to the plug list
1058 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1059 * the plug list when the task sleeps by itself. For details, please see
1060 * schedule() where blk_schedule_flush_plug() is called.
1063 struct list_head list; /* requests */
1064 struct list_head mq_list; /* blk-mq requests */
1065 struct list_head cb_list; /* md requires an unplug callback */
1067 #define BLK_MAX_REQUEST_COUNT 16
1070 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1071 struct blk_plug_cb {
1072 struct list_head list;
1073 blk_plug_cb_fn callback;
1076 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1077 void *data, int size);
1078 extern void blk_start_plug(struct blk_plug *);
1079 extern void blk_finish_plug(struct blk_plug *);
1080 extern void blk_flush_plug_list(struct blk_plug *, bool);
1082 static inline void blk_flush_plug(struct task_struct *tsk)
1084 struct blk_plug *plug = tsk->plug;
1087 blk_flush_plug_list(plug, false);
1090 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1092 struct blk_plug *plug = tsk->plug;
1095 blk_flush_plug_list(plug, true);
1098 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1100 struct blk_plug *plug = tsk->plug;
1103 (!list_empty(&plug->list) ||
1104 !list_empty(&plug->mq_list) ||
1105 !list_empty(&plug->cb_list));
1111 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1112 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1113 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1114 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1115 extern void blk_queue_free_tags(struct request_queue *);
1116 extern int blk_queue_resize_tags(struct request_queue *, int);
1117 extern void blk_queue_invalidate_tags(struct request_queue *);
1118 extern struct blk_queue_tag *blk_init_tags(int, int);
1119 extern void blk_free_tags(struct blk_queue_tag *);
1121 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1124 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1126 return bqt->tag_index[tag];
1129 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1131 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1132 extern int blkdev_issue_barrier(struct block_device *, gfp_t, sector_t *);
1133 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1134 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1135 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1136 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1137 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1138 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1139 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1140 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1142 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1143 nr_blocks << (sb->s_blocksize_bits - 9),
1146 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1147 sector_t nr_blocks, gfp_t gfp_mask)
1149 return blkdev_issue_zeroout(sb->s_bdev,
1150 block << (sb->s_blocksize_bits - 9),
1151 nr_blocks << (sb->s_blocksize_bits - 9),
1155 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1157 enum blk_default_limits {
1158 BLK_MAX_SEGMENTS = 128,
1159 BLK_SAFE_MAX_SECTORS = 255,
1160 BLK_DEF_MAX_SECTORS = 2560,
1161 BLK_MAX_SEGMENT_SIZE = 65536,
1162 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1165 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1167 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1169 return q->limits.bounce_pfn;
1172 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1174 return q->limits.seg_boundary_mask;
1177 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1179 return q->limits.virt_boundary_mask;
1182 static inline unsigned int queue_max_sectors(struct request_queue *q)
1184 return q->limits.max_sectors;
1187 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1189 return q->limits.max_hw_sectors;
1192 static inline unsigned short queue_max_segments(struct request_queue *q)
1194 return q->limits.max_segments;
1197 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1199 return q->limits.max_segment_size;
1202 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1206 if (q && q->limits.logical_block_size)
1207 retval = q->limits.logical_block_size;
1212 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1214 return queue_logical_block_size(bdev_get_queue(bdev));
1217 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1219 return q->limits.physical_block_size;
1222 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1224 return queue_physical_block_size(bdev_get_queue(bdev));
1227 static inline unsigned int queue_io_min(struct request_queue *q)
1229 return q->limits.io_min;
1232 static inline int bdev_io_min(struct block_device *bdev)
1234 return queue_io_min(bdev_get_queue(bdev));
1237 static inline unsigned int queue_io_opt(struct request_queue *q)
1239 return q->limits.io_opt;
1242 static inline int bdev_io_opt(struct block_device *bdev)
1244 return queue_io_opt(bdev_get_queue(bdev));
1247 static inline int queue_alignment_offset(struct request_queue *q)
1249 if (q->limits.misaligned)
1252 return q->limits.alignment_offset;
1255 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1257 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1258 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1260 return (granularity + lim->alignment_offset - alignment) % granularity;
1263 static inline int bdev_alignment_offset(struct block_device *bdev)
1265 struct request_queue *q = bdev_get_queue(bdev);
1267 if (q->limits.misaligned)
1270 if (bdev != bdev->bd_contains)
1271 return bdev->bd_part->alignment_offset;
1273 return q->limits.alignment_offset;
1276 static inline int queue_discard_alignment(struct request_queue *q)
1278 if (q->limits.discard_misaligned)
1281 return q->limits.discard_alignment;
1284 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1286 unsigned int alignment, granularity, offset;
1288 if (!lim->max_discard_sectors)
1291 /* Why are these in bytes, not sectors? */
1292 alignment = lim->discard_alignment >> 9;
1293 granularity = lim->discard_granularity >> 9;
1297 /* Offset of the partition start in 'granularity' sectors */
1298 offset = sector_div(sector, granularity);
1300 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1301 offset = (granularity + alignment - offset) % granularity;
1303 /* Turn it back into bytes, gaah */
1307 static inline int bdev_discard_alignment(struct block_device *bdev)
1309 struct request_queue *q = bdev_get_queue(bdev);
1311 if (bdev != bdev->bd_contains)
1312 return bdev->bd_part->discard_alignment;
1314 return q->limits.discard_alignment;
1317 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1319 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1325 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1327 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1330 static inline unsigned int bdev_write_same(struct block_device *bdev)
1332 struct request_queue *q = bdev_get_queue(bdev);
1335 return q->limits.max_write_same_sectors;
1340 static inline int queue_dma_alignment(struct request_queue *q)
1342 return q ? q->dma_alignment : 511;
1345 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1348 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1349 return !(addr & alignment) && !(len & alignment);
1352 /* assumes size > 256 */
1353 static inline unsigned int blksize_bits(unsigned int size)
1355 unsigned int bits = 8;
1359 } while (size > 256);
1363 static inline unsigned int block_size(struct block_device *bdev)
1365 return bdev->bd_block_size;
1368 static inline bool queue_flush_queueable(struct request_queue *q)
1370 return !q->flush_not_queueable;
1373 typedef struct {struct page *v;} Sector;
1375 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1377 static inline void put_dev_sector(Sector p)
1379 page_cache_release(p.v);
1382 static inline bool __bvec_gap_to_prev(struct request_queue *q,
1383 struct bio_vec *bprv, unsigned int offset)
1386 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1390 * Check if adding a bio_vec after bprv with offset would create a gap in
1391 * the SG list. Most drivers don't care about this, but some do.
1393 static inline bool bvec_gap_to_prev(struct request_queue *q,
1394 struct bio_vec *bprv, unsigned int offset)
1396 if (!queue_virt_boundary(q))
1398 return __bvec_gap_to_prev(q, bprv, offset);
1401 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1404 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1405 struct bio_vec pb, nb;
1407 bio_get_last_bvec(prev, &pb);
1408 bio_get_first_bvec(next, &nb);
1410 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1416 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1418 return bio_will_gap(req->q, req->biotail, bio);
1421 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1423 return bio_will_gap(req->q, bio, req->bio);
1427 int kblockd_schedule_work(struct work_struct *work);
1428 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1429 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1431 #ifdef CONFIG_BLK_CGROUP
1433 * This should not be using sched_clock(). A real patch is in progress
1434 * to fix this up, until that is in place we need to disable preemption
1435 * around sched_clock() in this function and set_io_start_time_ns().
1437 static inline void set_start_time_ns(struct request *req)
1440 req->start_time_ns = sched_clock();
1444 static inline void set_io_start_time_ns(struct request *req)
1447 req->io_start_time_ns = sched_clock();
1451 static inline uint64_t rq_start_time_ns(struct request *req)
1453 return req->start_time_ns;
1456 static inline uint64_t rq_io_start_time_ns(struct request *req)
1458 return req->io_start_time_ns;
1461 static inline void set_start_time_ns(struct request *req) {}
1462 static inline void set_io_start_time_ns(struct request *req) {}
1463 static inline uint64_t rq_start_time_ns(struct request *req)
1467 static inline uint64_t rq_io_start_time_ns(struct request *req)
1473 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1474 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1475 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1476 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1478 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1480 enum blk_integrity_flags {
1481 BLK_INTEGRITY_VERIFY = 1 << 0,
1482 BLK_INTEGRITY_GENERATE = 1 << 1,
1483 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1484 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1487 struct blk_integrity_iter {
1491 unsigned int data_size;
1492 unsigned short interval;
1493 const char *disk_name;
1496 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1498 struct blk_integrity_profile {
1499 integrity_processing_fn *generate_fn;
1500 integrity_processing_fn *verify_fn;
1504 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1505 extern void blk_integrity_unregister(struct gendisk *);
1506 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1507 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1508 struct scatterlist *);
1509 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1510 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1512 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1515 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1517 struct blk_integrity *bi = &disk->queue->integrity;
1526 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1528 return blk_get_integrity(bdev->bd_disk);
1531 static inline bool blk_integrity_rq(struct request *rq)
1533 return rq->cmd_flags & REQ_INTEGRITY;
1536 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1539 q->limits.max_integrity_segments = segs;
1542 static inline unsigned short
1543 queue_max_integrity_segments(struct request_queue *q)
1545 return q->limits.max_integrity_segments;
1548 static inline bool integrity_req_gap_back_merge(struct request *req,
1551 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1552 struct bio_integrity_payload *bip_next = bio_integrity(next);
1554 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1555 bip_next->bip_vec[0].bv_offset);
1558 static inline bool integrity_req_gap_front_merge(struct request *req,
1561 struct bio_integrity_payload *bip = bio_integrity(bio);
1562 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1564 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1565 bip_next->bip_vec[0].bv_offset);
1568 #else /* CONFIG_BLK_DEV_INTEGRITY */
1571 struct block_device;
1573 struct blk_integrity;
1575 static inline int blk_integrity_rq(struct request *rq)
1579 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1584 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1586 struct scatterlist *s)
1590 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1594 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1598 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1602 static inline void blk_integrity_register(struct gendisk *d,
1603 struct blk_integrity *b)
1606 static inline void blk_integrity_unregister(struct gendisk *d)
1609 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1613 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1617 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1623 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1630 static inline bool integrity_req_gap_back_merge(struct request *req,
1635 static inline bool integrity_req_gap_front_merge(struct request *req,
1641 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1643 struct block_device_operations {
1644 int (*open) (struct block_device *, fmode_t);
1645 void (*release) (struct gendisk *, fmode_t);
1646 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1647 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1648 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1649 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
1650 unsigned long *pfn);
1651 unsigned int (*check_events) (struct gendisk *disk,
1652 unsigned int clearing);
1653 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1654 int (*media_changed) (struct gendisk *);
1655 void (*unlock_native_capacity) (struct gendisk *);
1656 int (*revalidate_disk) (struct gendisk *);
1657 int (*getgeo)(struct block_device *, struct hd_geometry *);
1658 /* this callback is with swap_lock and sometimes page table lock held */
1659 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1660 struct module *owner;
1661 const struct pr_ops *pr_ops;
1664 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1666 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1667 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1668 struct writeback_control *);
1669 extern long bdev_direct_access(struct block_device *, sector_t,
1670 void __pmem **addr, unsigned long *pfn, long size);
1673 * X-axis for IO latency histogram support.
1675 static const u_int64_t latency_x_axis_us[] = {
1701 #define BLK_IO_LAT_HIST_DISABLE 0
1702 #define BLK_IO_LAT_HIST_ENABLE 1
1703 #define BLK_IO_LAT_HIST_ZERO 2
1705 struct io_latency_state {
1706 u_int64_t latency_y_axis[ARRAY_SIZE(latency_x_axis_us) + 1];
1707 u_int64_t latency_elems;
1708 u_int64_t latency_sum;
1712 blk_update_latency_hist(struct io_latency_state *s, u_int64_t delta_us)
1716 for (i = 0; i < ARRAY_SIZE(latency_x_axis_us); i++)
1717 if (delta_us < (u_int64_t)latency_x_axis_us[i])
1719 s->latency_y_axis[i]++;
1721 s->latency_sum += delta_us;
1724 ssize_t blk_latency_hist_show(char* name, struct io_latency_state *s,
1725 char *buf, int buf_size);
1727 #else /* CONFIG_BLOCK */
1729 struct block_device;
1732 * stubs for when the block layer is configured out
1734 #define buffer_heads_over_limit 0
1736 static inline long nr_blockdev_pages(void)
1744 static inline void blk_start_plug(struct blk_plug *plug)
1748 static inline void blk_finish_plug(struct blk_plug *plug)
1752 static inline void blk_flush_plug(struct task_struct *task)
1756 static inline void blk_schedule_flush_plug(struct task_struct *task)
1761 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1766 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1767 sector_t *error_sector)
1772 #endif /* CONFIG_BLOCK */