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/pfn.h>
19 #include <linux/bio.h>
20 #include <linux/stringify.h>
21 #include <linux/gfp.h>
22 #include <linux/bsg.h>
23 #include <linux/smp.h>
24 #include <linux/rcupdate.h>
25 #include <linux/percpu-refcount.h>
26 #include <linux/scatterlist.h>
29 struct scsi_ioctl_command;
32 struct elevator_queue;
38 struct blk_flush_queue;
41 #define BLKDEV_MIN_RQ 4
42 #define BLKDEV_MAX_RQ 128 /* Default maximum */
45 * Maximum number of blkcg policies allowed to be registered concurrently.
46 * Defined here to simplify include dependency.
48 #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;
95 struct request_queue *q;
96 struct blk_mq_ctx *mq_ctx;
101 unsigned long atomic_flags;
103 /* the following two fields are internal, NEVER access directly */
104 unsigned int __data_len; /* total data len */
105 sector_t __sector; /* sector cursor */
111 * The hash is used inside the scheduler, and killed once the
112 * request reaches the dispatch list. The ipi_list is only used
113 * to queue the request for softirq completion, which is long
114 * after the request has been unhashed (and even removed from
115 * the dispatch list).
118 struct hlist_node hash; /* merge hash */
119 struct list_head ipi_list;
123 * The rb_node is only used inside the io scheduler, requests
124 * are pruned when moved to the dispatch queue. So let the
125 * completion_data share space with the rb_node.
128 struct rb_node rb_node; /* sort/lookup */
129 void *completion_data;
133 * Three pointers are available for the IO schedulers, if they need
134 * more they have to dynamically allocate it. Flush requests are
135 * never put on the IO scheduler. So let the flush fields share
136 * space with the elevator data.
146 struct list_head list;
147 rq_end_io_fn *saved_end_io;
151 struct gendisk *rq_disk;
152 struct hd_struct *part;
153 unsigned long start_time;
154 #ifdef CONFIG_BLK_CGROUP
155 struct request_list *rl; /* rl this rq is alloced from */
156 unsigned long long start_time_ns;
157 unsigned long long io_start_time_ns; /* when passed to hardware */
159 /* Number of scatter-gather DMA addr+len pairs after
160 * physical address coalescing is performed.
162 unsigned short nr_phys_segments;
163 #if defined(CONFIG_BLK_DEV_INTEGRITY)
164 unsigned short nr_integrity_segments;
167 unsigned short ioprio;
169 void *special; /* opaque pointer available for LLD use */
175 * when request is used as a packet command carrier
177 unsigned char __cmd[BLK_MAX_CDB];
179 unsigned short cmd_len;
181 unsigned int extra_len; /* length of alignment and padding */
182 unsigned int sense_len;
183 unsigned int resid_len; /* residual count */
186 unsigned long deadline;
187 struct list_head timeout_list;
188 unsigned int timeout;
192 * completion callback.
194 rq_end_io_fn *end_io;
198 struct request *next_rq;
201 #define REQ_OP_SHIFT (8 * sizeof(u64) - REQ_OP_BITS)
202 #define req_op(req) ((req)->cmd_flags >> REQ_OP_SHIFT)
204 #define req_set_op(req, op) do { \
205 WARN_ON(op >= (1 << REQ_OP_BITS)); \
206 (req)->cmd_flags &= ((1ULL << REQ_OP_SHIFT) - 1); \
207 (req)->cmd_flags |= ((u64) (op) << REQ_OP_SHIFT); \
210 #define req_set_op_attrs(req, op, flags) do { \
211 req_set_op(req, op); \
212 (req)->cmd_flags |= flags; \
215 static inline unsigned short req_get_ioprio(struct request *req)
220 #include <linux/elevator.h>
222 struct blk_queue_ctx;
224 typedef void (request_fn_proc) (struct request_queue *q);
225 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
226 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
227 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
230 typedef void (softirq_done_fn)(struct request *);
231 typedef int (dma_drain_needed_fn)(struct request *);
232 typedef int (lld_busy_fn) (struct request_queue *q);
233 typedef int (bsg_job_fn) (struct bsg_job *);
235 enum blk_eh_timer_return {
241 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
243 enum blk_queue_state {
248 struct blk_queue_tag {
249 struct request **tag_index; /* map of busy tags */
250 unsigned long *tag_map; /* bit map of free/busy tags */
251 int busy; /* current depth */
252 int max_depth; /* what we will send to device */
253 int real_max_depth; /* what the array can hold */
254 atomic_t refcnt; /* map can be shared */
255 int alloc_policy; /* tag allocation policy */
256 int next_tag; /* next tag */
258 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
259 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
261 #define BLK_SCSI_MAX_CMDS (256)
262 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
265 * Zoned block device models (zoned limit).
267 enum blk_zoned_model {
268 BLK_ZONED_NONE, /* Regular block device */
269 BLK_ZONED_HA, /* Host-aware zoned block device */
270 BLK_ZONED_HM, /* Host-managed zoned block device */
273 struct queue_limits {
274 unsigned long bounce_pfn;
275 unsigned long seg_boundary_mask;
276 unsigned long virt_boundary_mask;
278 unsigned int max_hw_sectors;
279 unsigned int max_dev_sectors;
280 unsigned int chunk_sectors;
281 unsigned int max_sectors;
282 unsigned int max_segment_size;
283 unsigned int physical_block_size;
284 unsigned int alignment_offset;
287 unsigned int max_discard_sectors;
288 unsigned int max_hw_discard_sectors;
289 unsigned int max_write_same_sectors;
290 unsigned int discard_granularity;
291 unsigned int discard_alignment;
293 unsigned short logical_block_size;
294 unsigned short max_segments;
295 unsigned short max_integrity_segments;
297 unsigned char misaligned;
298 unsigned char discard_misaligned;
299 unsigned char cluster;
300 unsigned char discard_zeroes_data;
301 unsigned char raid_partial_stripes_expensive;
302 enum blk_zoned_model zoned;
305 struct request_queue {
307 * Together with queue_head for cacheline sharing
309 struct list_head queue_head;
310 struct request *last_merge;
311 struct elevator_queue *elevator;
312 int nr_rqs[2]; /* # allocated [a]sync rqs */
313 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
316 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
317 * is used, root blkg allocates from @q->root_rl and all other
318 * blkgs from their own blkg->rl. Which one to use should be
319 * determined using bio_request_list().
321 struct request_list root_rl;
323 request_fn_proc *request_fn;
324 make_request_fn *make_request_fn;
325 prep_rq_fn *prep_rq_fn;
326 unprep_rq_fn *unprep_rq_fn;
327 softirq_done_fn *softirq_done_fn;
328 rq_timed_out_fn *rq_timed_out_fn;
329 dma_drain_needed_fn *dma_drain_needed;
330 lld_busy_fn *lld_busy_fn;
332 struct blk_mq_ops *mq_ops;
334 unsigned int *mq_map;
337 struct blk_mq_ctx __percpu *queue_ctx;
338 unsigned int nr_queues;
340 /* hw dispatch queues */
341 struct blk_mq_hw_ctx **queue_hw_ctx;
342 unsigned int nr_hw_queues;
345 * Dispatch queue sorting
348 struct request *boundary_rq;
351 * Delayed queue handling
353 struct delayed_work delay_work;
355 struct backing_dev_info backing_dev_info;
358 * The queue owner gets to use this for whatever they like.
359 * ll_rw_blk doesn't touch it.
364 * various queue flags, see QUEUE_* below
366 unsigned long queue_flags;
369 * ida allocated id for this queue. Used to index queues from
375 * queue needs bounce pages for pages above this limit
380 * protects queue structures from reentrancy. ->__queue_lock should
381 * _never_ be used directly, it is queue private. always use
384 spinlock_t __queue_lock;
385 spinlock_t *queue_lock;
395 struct kobject mq_kobj;
397 #ifdef CONFIG_BLK_DEV_INTEGRITY
398 struct blk_integrity integrity;
399 #endif /* CONFIG_BLK_DEV_INTEGRITY */
404 unsigned int nr_pending;
410 unsigned long nr_requests; /* Max # of requests */
411 unsigned int nr_congestion_on;
412 unsigned int nr_congestion_off;
413 unsigned int nr_batching;
415 unsigned int dma_drain_size;
416 void *dma_drain_buffer;
417 unsigned int dma_pad_mask;
418 unsigned int dma_alignment;
420 struct blk_queue_tag *queue_tags;
421 struct list_head tag_busy_list;
423 unsigned int nr_sorted;
424 unsigned int in_flight[2];
426 * Number of active block driver functions for which blk_drain_queue()
427 * must wait. Must be incremented around functions that unlock the
428 * queue_lock internally, e.g. scsi_request_fn().
430 unsigned int request_fn_active;
432 unsigned int rq_timeout;
433 struct timer_list timeout;
434 struct work_struct timeout_work;
435 struct list_head timeout_list;
437 struct list_head icq_list;
438 #ifdef CONFIG_BLK_CGROUP
439 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
440 struct blkcg_gq *root_blkg;
441 struct list_head blkg_list;
444 struct queue_limits limits;
449 unsigned int sg_timeout;
450 unsigned int sg_reserved_size;
452 #ifdef CONFIG_BLK_DEV_IO_TRACE
453 struct blk_trace *blk_trace;
456 * for flush operations
458 struct blk_flush_queue *fq;
460 struct list_head requeue_list;
461 spinlock_t requeue_lock;
462 struct delayed_work requeue_work;
464 struct mutex sysfs_lock;
467 atomic_t mq_freeze_depth;
469 #if defined(CONFIG_BLK_DEV_BSG)
470 bsg_job_fn *bsg_job_fn;
472 struct bsg_class_device bsg_dev;
475 #ifdef CONFIG_BLK_DEV_THROTTLING
477 struct throtl_data *td;
479 struct rcu_head rcu_head;
480 wait_queue_head_t mq_freeze_wq;
481 struct percpu_ref q_usage_counter;
482 struct list_head all_q_node;
484 struct blk_mq_tag_set *tag_set;
485 struct list_head tag_set_list;
486 struct bio_set *bio_split;
488 bool mq_sysfs_init_done;
491 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
492 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
493 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
494 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
495 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
496 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
497 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
498 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
499 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
500 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
501 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
502 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
503 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
504 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
505 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
506 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
507 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
508 #define QUEUE_FLAG_SECERASE 17 /* supports secure erase */
509 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
510 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
511 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
512 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
513 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
514 #define QUEUE_FLAG_WC 23 /* Write back caching */
515 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
516 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
517 #define QUEUE_FLAG_DAX 26 /* device supports DAX */
519 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
520 (1 << QUEUE_FLAG_STACKABLE) | \
521 (1 << QUEUE_FLAG_SAME_COMP) | \
522 (1 << QUEUE_FLAG_ADD_RANDOM))
524 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
525 (1 << QUEUE_FLAG_STACKABLE) | \
526 (1 << QUEUE_FLAG_SAME_COMP) | \
527 (1 << QUEUE_FLAG_POLL))
529 static inline void queue_lockdep_assert_held(struct request_queue *q)
532 lockdep_assert_held(q->queue_lock);
535 static inline void queue_flag_set_unlocked(unsigned int flag,
536 struct request_queue *q)
538 __set_bit(flag, &q->queue_flags);
541 static inline int queue_flag_test_and_clear(unsigned int flag,
542 struct request_queue *q)
544 queue_lockdep_assert_held(q);
546 if (test_bit(flag, &q->queue_flags)) {
547 __clear_bit(flag, &q->queue_flags);
554 static inline int queue_flag_test_and_set(unsigned int flag,
555 struct request_queue *q)
557 queue_lockdep_assert_held(q);
559 if (!test_bit(flag, &q->queue_flags)) {
560 __set_bit(flag, &q->queue_flags);
567 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
569 queue_lockdep_assert_held(q);
570 __set_bit(flag, &q->queue_flags);
573 static inline void queue_flag_clear_unlocked(unsigned int flag,
574 struct request_queue *q)
576 __clear_bit(flag, &q->queue_flags);
579 static inline int queue_in_flight(struct request_queue *q)
581 return q->in_flight[0] + q->in_flight[1];
584 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
586 queue_lockdep_assert_held(q);
587 __clear_bit(flag, &q->queue_flags);
590 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
591 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
592 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
593 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
594 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
595 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
596 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
597 #define blk_queue_noxmerges(q) \
598 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
599 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
600 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
601 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
602 #define blk_queue_stackable(q) \
603 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
604 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
605 #define blk_queue_secure_erase(q) \
606 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
607 #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
609 #define blk_noretry_request(rq) \
610 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
611 REQ_FAILFAST_DRIVER))
613 #define blk_account_rq(rq) \
614 (((rq)->cmd_flags & REQ_STARTED) && \
615 ((rq)->cmd_type == REQ_TYPE_FS))
617 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
618 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
619 /* rq->queuelist of dequeued request must be list_empty() */
620 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
622 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
624 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
627 * Driver can handle struct request, if it either has an old style
628 * request_fn defined, or is blk-mq based.
630 static inline bool queue_is_rq_based(struct request_queue *q)
632 return q->request_fn || q->mq_ops;
635 static inline unsigned int blk_queue_cluster(struct request_queue *q)
637 return q->limits.cluster;
640 static inline enum blk_zoned_model
641 blk_queue_zoned_model(struct request_queue *q)
643 return q->limits.zoned;
646 static inline bool blk_queue_is_zoned(struct request_queue *q)
648 switch (blk_queue_zoned_model(q)) {
658 * We regard a request as sync, if either a read or a sync write
660 static inline bool rw_is_sync(int op, unsigned int rw_flags)
662 return op == REQ_OP_READ || (rw_flags & REQ_SYNC);
665 static inline bool rq_is_sync(struct request *rq)
667 return rw_is_sync(req_op(rq), rq->cmd_flags);
670 static inline bool blk_rl_full(struct request_list *rl, bool sync)
672 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
674 return rl->flags & flag;
677 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
679 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
684 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
686 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
691 static inline bool rq_mergeable(struct request *rq)
693 if (rq->cmd_type != REQ_TYPE_FS)
696 if (req_op(rq) == REQ_OP_FLUSH)
699 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
705 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
707 if (bio_data(a) == bio_data(b))
714 * q->prep_rq_fn return values
717 BLKPREP_OK, /* serve it */
718 BLKPREP_KILL, /* fatal error, kill, return -EIO */
719 BLKPREP_DEFER, /* leave on queue */
720 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */
723 extern unsigned long blk_max_low_pfn, blk_max_pfn;
726 * standard bounce addresses:
728 * BLK_BOUNCE_HIGH : bounce all highmem pages
729 * BLK_BOUNCE_ANY : don't bounce anything
730 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
733 #if BITS_PER_LONG == 32
734 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
736 #define BLK_BOUNCE_HIGH -1ULL
738 #define BLK_BOUNCE_ANY (-1ULL)
739 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
742 * default timeout for SG_IO if none specified
744 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
745 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
748 extern int init_emergency_isa_pool(void);
749 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
751 static inline int init_emergency_isa_pool(void)
755 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
758 #endif /* CONFIG_MMU */
764 unsigned long offset;
769 struct req_iterator {
770 struct bvec_iter iter;
774 /* This should not be used directly - use rq_for_each_segment */
775 #define for_each_bio(_bio) \
776 for (; _bio; _bio = _bio->bi_next)
777 #define __rq_for_each_bio(_bio, rq) \
779 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
781 #define rq_for_each_segment(bvl, _rq, _iter) \
782 __rq_for_each_bio(_iter.bio, _rq) \
783 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
785 #define rq_iter_last(bvec, _iter) \
786 (_iter.bio->bi_next == NULL && \
787 bio_iter_last(bvec, _iter.iter))
789 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
790 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
792 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
793 extern void rq_flush_dcache_pages(struct request *rq);
795 static inline void rq_flush_dcache_pages(struct request *rq)
801 #define vfs_msg(sb, level, fmt, ...) \
802 __vfs_msg(sb, level, fmt, ##__VA_ARGS__)
804 #define vfs_msg(sb, level, fmt, ...) \
806 no_printk(fmt, ##__VA_ARGS__); \
807 __vfs_msg(sb, "", " "); \
811 extern int blk_register_queue(struct gendisk *disk);
812 extern void blk_unregister_queue(struct gendisk *disk);
813 extern blk_qc_t generic_make_request(struct bio *bio);
814 extern void blk_rq_init(struct request_queue *q, struct request *rq);
815 extern void blk_put_request(struct request *);
816 extern void __blk_put_request(struct request_queue *, struct request *);
817 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
818 extern void blk_rq_set_block_pc(struct request *);
819 extern void blk_requeue_request(struct request_queue *, struct request *);
820 extern void blk_add_request_payload(struct request *rq, struct page *page,
821 int offset, unsigned int len);
822 extern int blk_lld_busy(struct request_queue *q);
823 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
824 struct bio_set *bs, gfp_t gfp_mask,
825 int (*bio_ctr)(struct bio *, struct bio *, void *),
827 extern void blk_rq_unprep_clone(struct request *rq);
828 extern int blk_insert_cloned_request(struct request_queue *q,
830 extern int blk_rq_append_bio(struct request *rq, struct bio *bio);
831 extern void blk_delay_queue(struct request_queue *, unsigned long);
832 extern void blk_queue_split(struct request_queue *, struct bio **,
834 extern void blk_recount_segments(struct request_queue *, struct bio *);
835 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
836 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
837 unsigned int, void __user *);
838 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
839 unsigned int, void __user *);
840 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
841 struct scsi_ioctl_command __user *);
843 extern int blk_queue_enter(struct request_queue *q, bool nowait);
844 extern void blk_queue_exit(struct request_queue *q);
845 extern void blk_start_queue(struct request_queue *q);
846 extern void blk_start_queue_async(struct request_queue *q);
847 extern void blk_stop_queue(struct request_queue *q);
848 extern void blk_sync_queue(struct request_queue *q);
849 extern void __blk_stop_queue(struct request_queue *q);
850 extern void __blk_run_queue(struct request_queue *q);
851 extern void __blk_run_queue_uncond(struct request_queue *q);
852 extern void blk_run_queue(struct request_queue *);
853 extern void blk_run_queue_async(struct request_queue *q);
854 extern int blk_rq_map_user(struct request_queue *, struct request *,
855 struct rq_map_data *, void __user *, unsigned long,
857 extern int blk_rq_unmap_user(struct bio *);
858 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
859 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
860 struct rq_map_data *, const struct iov_iter *,
862 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
863 struct request *, int);
864 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
865 struct request *, int, rq_end_io_fn *);
867 bool blk_poll(struct request_queue *q, blk_qc_t cookie);
869 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
871 return bdev->bd_disk->queue; /* this is never NULL */
875 * blk_rq_pos() : the current sector
876 * blk_rq_bytes() : bytes left in the entire request
877 * blk_rq_cur_bytes() : bytes left in the current segment
878 * blk_rq_err_bytes() : bytes left till the next error boundary
879 * blk_rq_sectors() : sectors left in the entire request
880 * blk_rq_cur_sectors() : sectors left in the current segment
882 static inline sector_t blk_rq_pos(const struct request *rq)
887 static inline unsigned int blk_rq_bytes(const struct request *rq)
889 return rq->__data_len;
892 static inline int blk_rq_cur_bytes(const struct request *rq)
894 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
897 extern unsigned int blk_rq_err_bytes(const struct request *rq);
899 static inline unsigned int blk_rq_sectors(const struct request *rq)
901 return blk_rq_bytes(rq) >> 9;
904 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
906 return blk_rq_cur_bytes(rq) >> 9;
909 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
912 if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
913 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
915 if (unlikely(op == REQ_OP_WRITE_SAME))
916 return q->limits.max_write_same_sectors;
918 return q->limits.max_sectors;
922 * Return maximum size of a request at given offset. Only valid for
923 * file system requests.
925 static inline unsigned int blk_max_size_offset(struct request_queue *q,
928 if (!q->limits.chunk_sectors)
929 return q->limits.max_sectors;
931 return q->limits.chunk_sectors -
932 (offset & (q->limits.chunk_sectors - 1));
935 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
938 struct request_queue *q = rq->q;
940 if (unlikely(rq->cmd_type != REQ_TYPE_FS))
941 return q->limits.max_hw_sectors;
943 if (!q->limits.chunk_sectors ||
944 req_op(rq) == REQ_OP_DISCARD ||
945 req_op(rq) == REQ_OP_SECURE_ERASE)
946 return blk_queue_get_max_sectors(q, req_op(rq));
948 return min(blk_max_size_offset(q, offset),
949 blk_queue_get_max_sectors(q, req_op(rq)));
952 static inline unsigned int blk_rq_count_bios(struct request *rq)
954 unsigned int nr_bios = 0;
957 __rq_for_each_bio(bio, rq)
964 * Request issue related functions.
966 extern struct request *blk_peek_request(struct request_queue *q);
967 extern void blk_start_request(struct request *rq);
968 extern struct request *blk_fetch_request(struct request_queue *q);
971 * Request completion related functions.
973 * blk_update_request() completes given number of bytes and updates
974 * the request without completing it.
976 * blk_end_request() and friends. __blk_end_request() must be called
977 * with the request queue spinlock acquired.
979 * Several drivers define their own end_request and call
980 * blk_end_request() for parts of the original function.
981 * This prevents code duplication in drivers.
983 extern bool blk_update_request(struct request *rq, int error,
984 unsigned int nr_bytes);
985 extern void blk_finish_request(struct request *rq, int error);
986 extern bool blk_end_request(struct request *rq, int error,
987 unsigned int nr_bytes);
988 extern void blk_end_request_all(struct request *rq, int error);
989 extern bool blk_end_request_cur(struct request *rq, int error);
990 extern bool blk_end_request_err(struct request *rq, int error);
991 extern bool __blk_end_request(struct request *rq, int error,
992 unsigned int nr_bytes);
993 extern void __blk_end_request_all(struct request *rq, int error);
994 extern bool __blk_end_request_cur(struct request *rq, int error);
995 extern bool __blk_end_request_err(struct request *rq, int error);
997 extern void blk_complete_request(struct request *);
998 extern void __blk_complete_request(struct request *);
999 extern void blk_abort_request(struct request *);
1000 extern void blk_unprep_request(struct request *);
1003 * Access functions for manipulating queue properties
1005 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
1006 spinlock_t *lock, int node_id);
1007 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
1008 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
1009 request_fn_proc *, spinlock_t *);
1010 extern void blk_cleanup_queue(struct request_queue *);
1011 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1012 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1013 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1014 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1015 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1016 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1017 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1018 unsigned int max_discard_sectors);
1019 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1020 unsigned int max_write_same_sectors);
1021 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
1022 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1023 extern void blk_queue_alignment_offset(struct request_queue *q,
1024 unsigned int alignment);
1025 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1026 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1027 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1028 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1029 extern void blk_set_default_limits(struct queue_limits *lim);
1030 extern void blk_set_stacking_limits(struct queue_limits *lim);
1031 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1033 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1035 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1037 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1038 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1039 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1040 extern int blk_queue_dma_drain(struct request_queue *q,
1041 dma_drain_needed_fn *dma_drain_needed,
1042 void *buf, unsigned int size);
1043 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1044 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1045 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1046 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1047 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1048 extern void blk_queue_dma_alignment(struct request_queue *, int);
1049 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1050 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1051 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1052 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1053 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1054 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1055 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1057 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1058 extern void blk_dump_rq_flags(struct request *, char *);
1059 extern long nr_blockdev_pages(void);
1061 bool __must_check blk_get_queue(struct request_queue *);
1062 struct request_queue *blk_alloc_queue(gfp_t);
1063 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1064 extern void blk_put_queue(struct request_queue *);
1065 extern void blk_set_queue_dying(struct request_queue *);
1068 * block layer runtime pm functions
1071 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1072 extern int blk_pre_runtime_suspend(struct request_queue *q);
1073 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1074 extern void blk_pre_runtime_resume(struct request_queue *q);
1075 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1076 extern void blk_set_runtime_active(struct request_queue *q);
1078 static inline void blk_pm_runtime_init(struct request_queue *q,
1079 struct device *dev) {}
1080 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1084 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1085 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1086 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1087 extern inline void blk_set_runtime_active(struct request_queue *q) {}
1091 * blk_plug permits building a queue of related requests by holding the I/O
1092 * fragments for a short period. This allows merging of sequential requests
1093 * into single larger request. As the requests are moved from a per-task list to
1094 * the device's request_queue in a batch, this results in improved scalability
1095 * as the lock contention for request_queue lock is reduced.
1097 * It is ok not to disable preemption when adding the request to the plug list
1098 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1099 * the plug list when the task sleeps by itself. For details, please see
1100 * schedule() where blk_schedule_flush_plug() is called.
1103 struct list_head list; /* requests */
1104 struct list_head mq_list; /* blk-mq requests */
1105 struct list_head cb_list; /* md requires an unplug callback */
1107 #define BLK_MAX_REQUEST_COUNT 16
1110 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1111 struct blk_plug_cb {
1112 struct list_head list;
1113 blk_plug_cb_fn callback;
1116 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1117 void *data, int size);
1118 extern void blk_start_plug(struct blk_plug *);
1119 extern void blk_finish_plug(struct blk_plug *);
1120 extern void blk_flush_plug_list(struct blk_plug *, bool);
1122 static inline void blk_flush_plug(struct task_struct *tsk)
1124 struct blk_plug *plug = tsk->plug;
1127 blk_flush_plug_list(plug, false);
1130 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1132 struct blk_plug *plug = tsk->plug;
1135 blk_flush_plug_list(plug, true);
1138 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1140 struct blk_plug *plug = tsk->plug;
1143 (!list_empty(&plug->list) ||
1144 !list_empty(&plug->mq_list) ||
1145 !list_empty(&plug->cb_list));
1151 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1152 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1153 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1154 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1155 extern void blk_queue_free_tags(struct request_queue *);
1156 extern int blk_queue_resize_tags(struct request_queue *, int);
1157 extern void blk_queue_invalidate_tags(struct request_queue *);
1158 extern struct blk_queue_tag *blk_init_tags(int, int);
1159 extern void blk_free_tags(struct blk_queue_tag *);
1161 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1164 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1166 return bqt->tag_index[tag];
1170 #define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */
1171 #define BLKDEV_DISCARD_ZERO (1 << 1) /* must reliably zero data */
1173 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1174 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1175 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1176 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1177 sector_t nr_sects, gfp_t gfp_mask, int flags,
1179 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1180 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1181 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1182 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1183 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1184 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1186 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1187 nr_blocks << (sb->s_blocksize_bits - 9),
1190 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1191 sector_t nr_blocks, gfp_t gfp_mask)
1193 return blkdev_issue_zeroout(sb->s_bdev,
1194 block << (sb->s_blocksize_bits - 9),
1195 nr_blocks << (sb->s_blocksize_bits - 9),
1199 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1201 enum blk_default_limits {
1202 BLK_MAX_SEGMENTS = 128,
1203 BLK_SAFE_MAX_SECTORS = 255,
1204 BLK_DEF_MAX_SECTORS = 2560,
1205 BLK_MAX_SEGMENT_SIZE = 65536,
1206 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1209 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1211 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1213 return q->limits.bounce_pfn;
1216 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1218 return q->limits.seg_boundary_mask;
1221 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1223 return q->limits.virt_boundary_mask;
1226 static inline unsigned int queue_max_sectors(struct request_queue *q)
1228 return q->limits.max_sectors;
1231 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1233 return q->limits.max_hw_sectors;
1236 static inline unsigned short queue_max_segments(struct request_queue *q)
1238 return q->limits.max_segments;
1241 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1243 return q->limits.max_segment_size;
1246 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1250 if (q && q->limits.logical_block_size)
1251 retval = q->limits.logical_block_size;
1256 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1258 return queue_logical_block_size(bdev_get_queue(bdev));
1261 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1263 return q->limits.physical_block_size;
1266 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1268 return queue_physical_block_size(bdev_get_queue(bdev));
1271 static inline unsigned int queue_io_min(struct request_queue *q)
1273 return q->limits.io_min;
1276 static inline int bdev_io_min(struct block_device *bdev)
1278 return queue_io_min(bdev_get_queue(bdev));
1281 static inline unsigned int queue_io_opt(struct request_queue *q)
1283 return q->limits.io_opt;
1286 static inline int bdev_io_opt(struct block_device *bdev)
1288 return queue_io_opt(bdev_get_queue(bdev));
1291 static inline int queue_alignment_offset(struct request_queue *q)
1293 if (q->limits.misaligned)
1296 return q->limits.alignment_offset;
1299 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1301 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1302 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1304 return (granularity + lim->alignment_offset - alignment) % granularity;
1307 static inline int bdev_alignment_offset(struct block_device *bdev)
1309 struct request_queue *q = bdev_get_queue(bdev);
1311 if (q->limits.misaligned)
1314 if (bdev != bdev->bd_contains)
1315 return bdev->bd_part->alignment_offset;
1317 return q->limits.alignment_offset;
1320 static inline int queue_discard_alignment(struct request_queue *q)
1322 if (q->limits.discard_misaligned)
1325 return q->limits.discard_alignment;
1328 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1330 unsigned int alignment, granularity, offset;
1332 if (!lim->max_discard_sectors)
1335 /* Why are these in bytes, not sectors? */
1336 alignment = lim->discard_alignment >> 9;
1337 granularity = lim->discard_granularity >> 9;
1341 /* Offset of the partition start in 'granularity' sectors */
1342 offset = sector_div(sector, granularity);
1344 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1345 offset = (granularity + alignment - offset) % granularity;
1347 /* Turn it back into bytes, gaah */
1351 static inline int bdev_discard_alignment(struct block_device *bdev)
1353 struct request_queue *q = bdev_get_queue(bdev);
1355 if (bdev != bdev->bd_contains)
1356 return bdev->bd_part->discard_alignment;
1358 return q->limits.discard_alignment;
1361 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1363 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1369 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1371 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1374 static inline unsigned int bdev_write_same(struct block_device *bdev)
1376 struct request_queue *q = bdev_get_queue(bdev);
1379 return q->limits.max_write_same_sectors;
1384 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
1386 struct request_queue *q = bdev_get_queue(bdev);
1389 return blk_queue_zoned_model(q);
1391 return BLK_ZONED_NONE;
1394 static inline bool bdev_is_zoned(struct block_device *bdev)
1396 struct request_queue *q = bdev_get_queue(bdev);
1399 return blk_queue_is_zoned(q);
1404 static inline int queue_dma_alignment(struct request_queue *q)
1406 return q ? q->dma_alignment : 511;
1409 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1412 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1413 return !(addr & alignment) && !(len & alignment);
1416 /* assumes size > 256 */
1417 static inline unsigned int blksize_bits(unsigned int size)
1419 unsigned int bits = 8;
1423 } while (size > 256);
1427 static inline unsigned int block_size(struct block_device *bdev)
1429 return bdev->bd_block_size;
1432 static inline bool queue_flush_queueable(struct request_queue *q)
1434 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags);
1437 typedef struct {struct page *v;} Sector;
1439 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1441 static inline void put_dev_sector(Sector p)
1446 static inline bool __bvec_gap_to_prev(struct request_queue *q,
1447 struct bio_vec *bprv, unsigned int offset)
1450 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1454 * Check if adding a bio_vec after bprv with offset would create a gap in
1455 * the SG list. Most drivers don't care about this, but some do.
1457 static inline bool bvec_gap_to_prev(struct request_queue *q,
1458 struct bio_vec *bprv, unsigned int offset)
1460 if (!queue_virt_boundary(q))
1462 return __bvec_gap_to_prev(q, bprv, offset);
1465 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1468 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1469 struct bio_vec pb, nb;
1471 bio_get_last_bvec(prev, &pb);
1472 bio_get_first_bvec(next, &nb);
1474 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1480 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1482 return bio_will_gap(req->q, req->biotail, bio);
1485 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1487 return bio_will_gap(req->q, bio, req->bio);
1490 int kblockd_schedule_work(struct work_struct *work);
1491 int kblockd_schedule_work_on(int cpu, struct work_struct *work);
1492 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1493 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1495 #ifdef CONFIG_BLK_CGROUP
1497 * This should not be using sched_clock(). A real patch is in progress
1498 * to fix this up, until that is in place we need to disable preemption
1499 * around sched_clock() in this function and set_io_start_time_ns().
1501 static inline void set_start_time_ns(struct request *req)
1504 req->start_time_ns = sched_clock();
1508 static inline void set_io_start_time_ns(struct request *req)
1511 req->io_start_time_ns = sched_clock();
1515 static inline uint64_t rq_start_time_ns(struct request *req)
1517 return req->start_time_ns;
1520 static inline uint64_t rq_io_start_time_ns(struct request *req)
1522 return req->io_start_time_ns;
1525 static inline void set_start_time_ns(struct request *req) {}
1526 static inline void set_io_start_time_ns(struct request *req) {}
1527 static inline uint64_t rq_start_time_ns(struct request *req)
1531 static inline uint64_t rq_io_start_time_ns(struct request *req)
1537 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1538 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1539 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1540 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1542 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1544 enum blk_integrity_flags {
1545 BLK_INTEGRITY_VERIFY = 1 << 0,
1546 BLK_INTEGRITY_GENERATE = 1 << 1,
1547 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1548 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1551 struct blk_integrity_iter {
1555 unsigned int data_size;
1556 unsigned short interval;
1557 const char *disk_name;
1560 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1562 struct blk_integrity_profile {
1563 integrity_processing_fn *generate_fn;
1564 integrity_processing_fn *verify_fn;
1568 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1569 extern void blk_integrity_unregister(struct gendisk *);
1570 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1571 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1572 struct scatterlist *);
1573 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1574 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1576 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1579 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1581 struct blk_integrity *bi = &disk->queue->integrity;
1590 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1592 return blk_get_integrity(bdev->bd_disk);
1595 static inline bool blk_integrity_rq(struct request *rq)
1597 return rq->cmd_flags & REQ_INTEGRITY;
1600 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1603 q->limits.max_integrity_segments = segs;
1606 static inline unsigned short
1607 queue_max_integrity_segments(struct request_queue *q)
1609 return q->limits.max_integrity_segments;
1612 static inline bool integrity_req_gap_back_merge(struct request *req,
1615 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1616 struct bio_integrity_payload *bip_next = bio_integrity(next);
1618 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1619 bip_next->bip_vec[0].bv_offset);
1622 static inline bool integrity_req_gap_front_merge(struct request *req,
1625 struct bio_integrity_payload *bip = bio_integrity(bio);
1626 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1628 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1629 bip_next->bip_vec[0].bv_offset);
1632 #else /* CONFIG_BLK_DEV_INTEGRITY */
1635 struct block_device;
1637 struct blk_integrity;
1639 static inline int blk_integrity_rq(struct request *rq)
1643 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1648 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1650 struct scatterlist *s)
1654 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1658 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1662 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1666 static inline void blk_integrity_register(struct gendisk *d,
1667 struct blk_integrity *b)
1670 static inline void blk_integrity_unregister(struct gendisk *d)
1673 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1677 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1681 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1687 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1694 static inline bool integrity_req_gap_back_merge(struct request *req,
1699 static inline bool integrity_req_gap_front_merge(struct request *req,
1705 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1708 * struct blk_dax_ctl - control and output parameters for ->direct_access
1709 * @sector: (input) offset relative to a block_device
1710 * @addr: (output) kernel virtual address for @sector populated by driver
1711 * @pfn: (output) page frame number for @addr populated by driver
1712 * @size: (input) number of bytes requested
1714 struct blk_dax_ctl {
1721 struct block_device_operations {
1722 int (*open) (struct block_device *, fmode_t);
1723 void (*release) (struct gendisk *, fmode_t);
1724 int (*rw_page)(struct block_device *, sector_t, struct page *, bool);
1725 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1726 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1727 long (*direct_access)(struct block_device *, sector_t, void **, pfn_t *,
1729 unsigned int (*check_events) (struct gendisk *disk,
1730 unsigned int clearing);
1731 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1732 int (*media_changed) (struct gendisk *);
1733 void (*unlock_native_capacity) (struct gendisk *);
1734 int (*revalidate_disk) (struct gendisk *);
1735 int (*getgeo)(struct block_device *, struct hd_geometry *);
1736 /* this callback is with swap_lock and sometimes page table lock held */
1737 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1738 struct module *owner;
1739 const struct pr_ops *pr_ops;
1742 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1744 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1745 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1746 struct writeback_control *);
1747 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *);
1748 extern int bdev_dax_supported(struct super_block *, int);
1749 extern bool bdev_dax_capable(struct block_device *);
1750 #else /* CONFIG_BLOCK */
1752 struct block_device;
1755 * stubs for when the block layer is configured out
1757 #define buffer_heads_over_limit 0
1759 static inline long nr_blockdev_pages(void)
1767 static inline void blk_start_plug(struct blk_plug *plug)
1771 static inline void blk_finish_plug(struct blk_plug *plug)
1775 static inline void blk_flush_plug(struct task_struct *task)
1779 static inline void blk_schedule_flush_plug(struct task_struct *task)
1784 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1789 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1790 sector_t *error_sector)
1795 #endif /* CONFIG_BLOCK */