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 static inline int blk_validate_block_size(unsigned int bsize)
54 if (bsize < 512 || bsize > PAGE_SIZE || !is_power_of_2(bsize))
60 #define BLK_RL_SYNCFULL (1U << 0)
61 #define BLK_RL_ASYNCFULL (1U << 1)
64 struct request_queue *q; /* the queue this rl belongs to */
65 #ifdef CONFIG_BLK_CGROUP
66 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
69 * count[], starved[], and wait[] are indexed by
70 * BLK_RW_SYNC/BLK_RW_ASYNC
75 wait_queue_head_t wait[2];
80 * request command types
82 enum rq_cmd_type_bits {
83 REQ_TYPE_FS = 1, /* fs request */
84 REQ_TYPE_BLOCK_PC, /* scsi command */
85 REQ_TYPE_DRV_PRIV, /* driver defined types from here */
88 #define BLK_MAX_CDB 16
91 * Try to put the fields that are referenced together in the same cacheline.
93 * If you modify this structure, make sure to update blk_rq_init() and
94 * especially blk_mq_rq_ctx_init() to take care of the added fields.
97 struct list_head queuelist;
99 struct call_single_data csd;
103 struct request_queue *q;
104 struct blk_mq_ctx *mq_ctx;
109 unsigned long atomic_flags;
111 /* the following two fields are internal, NEVER access directly */
112 unsigned int __data_len; /* total data len */
113 sector_t __sector; /* sector cursor */
119 * The hash is used inside the scheduler, and killed once the
120 * request reaches the dispatch list. The ipi_list is only used
121 * to queue the request for softirq completion, which is long
122 * after the request has been unhashed (and even removed from
123 * the dispatch list).
126 struct hlist_node hash; /* merge hash */
127 struct list_head ipi_list;
131 * The rb_node is only used inside the io scheduler, requests
132 * are pruned when moved to the dispatch queue. So let the
133 * completion_data share space with the rb_node.
136 struct rb_node rb_node; /* sort/lookup */
137 void *completion_data;
141 * Three pointers are available for the IO schedulers, if they need
142 * more they have to dynamically allocate it. Flush requests are
143 * never put on the IO scheduler. So let the flush fields share
144 * space with the elevator data.
154 struct list_head list;
155 rq_end_io_fn *saved_end_io;
159 struct gendisk *rq_disk;
160 struct hd_struct *part;
161 unsigned long start_time;
162 #ifdef CONFIG_BLK_CGROUP
163 struct request_list *rl; /* rl this rq is alloced from */
164 unsigned long long start_time_ns;
165 unsigned long long io_start_time_ns; /* when passed to hardware */
167 /* Number of scatter-gather DMA addr+len pairs after
168 * physical address coalescing is performed.
170 unsigned short nr_phys_segments;
171 #if defined(CONFIG_BLK_DEV_INTEGRITY)
172 unsigned short nr_integrity_segments;
175 unsigned short ioprio;
177 void *special; /* opaque pointer available for LLD use */
183 * when request is used as a packet command carrier
185 unsigned char __cmd[BLK_MAX_CDB];
187 unsigned short cmd_len;
189 unsigned int extra_len; /* length of alignment and padding */
190 unsigned int sense_len;
191 unsigned int resid_len; /* residual count */
194 unsigned long deadline;
195 struct list_head timeout_list;
196 unsigned int timeout;
200 * completion callback.
202 rq_end_io_fn *end_io;
206 struct request *next_rq;
209 #define REQ_OP_SHIFT (8 * sizeof(u64) - REQ_OP_BITS)
210 #define req_op(req) ((req)->cmd_flags >> REQ_OP_SHIFT)
212 #define req_set_op(req, op) do { \
213 WARN_ON(op >= (1 << REQ_OP_BITS)); \
214 (req)->cmd_flags &= ((1ULL << REQ_OP_SHIFT) - 1); \
215 (req)->cmd_flags |= ((u64) (op) << REQ_OP_SHIFT); \
218 #define req_set_op_attrs(req, op, flags) do { \
219 req_set_op(req, op); \
220 (req)->cmd_flags |= flags; \
223 static inline bool blk_rq_is_passthrough(struct request *rq)
225 return rq->cmd_type != REQ_TYPE_FS;
228 static inline unsigned short req_get_ioprio(struct request *req)
233 #include <linux/elevator.h>
235 struct blk_queue_ctx;
237 typedef void (request_fn_proc) (struct request_queue *q);
238 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
239 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
240 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
243 typedef void (softirq_done_fn)(struct request *);
244 typedef int (dma_drain_needed_fn)(struct request *);
245 typedef int (lld_busy_fn) (struct request_queue *q);
246 typedef int (bsg_job_fn) (struct bsg_job *);
248 enum blk_eh_timer_return {
254 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
256 enum blk_queue_state {
261 struct blk_queue_tag {
262 struct request **tag_index; /* map of busy tags */
263 unsigned long *tag_map; /* bit map of free/busy tags */
264 int busy; /* current depth */
265 int max_depth; /* what we will send to device */
266 int real_max_depth; /* what the array can hold */
267 atomic_t refcnt; /* map can be shared */
268 int alloc_policy; /* tag allocation policy */
269 int next_tag; /* next tag */
271 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
272 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
274 #define BLK_SCSI_MAX_CMDS (256)
275 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
277 struct queue_limits {
278 unsigned long bounce_pfn;
279 unsigned long seg_boundary_mask;
280 unsigned long virt_boundary_mask;
282 unsigned int max_hw_sectors;
283 unsigned int max_dev_sectors;
284 unsigned int chunk_sectors;
285 unsigned int max_sectors;
286 unsigned int max_segment_size;
287 unsigned int physical_block_size;
288 unsigned int logical_block_size;
289 unsigned int alignment_offset;
292 unsigned int max_discard_sectors;
293 unsigned int max_hw_discard_sectors;
294 unsigned int max_write_same_sectors;
295 unsigned int discard_granularity;
296 unsigned int discard_alignment;
298 unsigned short max_segments;
299 unsigned short max_integrity_segments;
301 unsigned char misaligned;
302 unsigned char discard_misaligned;
303 unsigned char cluster;
304 unsigned char discard_zeroes_data;
305 unsigned char raid_partial_stripes_expensive;
308 struct request_queue {
310 * Together with queue_head for cacheline sharing
312 struct list_head queue_head;
313 struct request *last_merge;
314 struct elevator_queue *elevator;
315 int nr_rqs[2]; /* # allocated [a]sync rqs */
316 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
319 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
320 * is used, root blkg allocates from @q->root_rl and all other
321 * blkgs from their own blkg->rl. Which one to use should be
322 * determined using bio_request_list().
324 struct request_list root_rl;
326 request_fn_proc *request_fn;
327 make_request_fn *make_request_fn;
328 prep_rq_fn *prep_rq_fn;
329 unprep_rq_fn *unprep_rq_fn;
330 softirq_done_fn *softirq_done_fn;
331 rq_timed_out_fn *rq_timed_out_fn;
332 dma_drain_needed_fn *dma_drain_needed;
333 lld_busy_fn *lld_busy_fn;
335 struct blk_mq_ops *mq_ops;
337 unsigned int *mq_map;
340 struct blk_mq_ctx __percpu *queue_ctx;
341 unsigned int nr_queues;
343 /* hw dispatch queues */
344 struct blk_mq_hw_ctx **queue_hw_ctx;
345 unsigned int nr_hw_queues;
348 * Dispatch queue sorting
351 struct request *boundary_rq;
354 * Delayed queue handling
356 struct delayed_work delay_work;
358 struct backing_dev_info backing_dev_info;
361 * The queue owner gets to use this for whatever they like.
362 * ll_rw_blk doesn't touch it.
367 * various queue flags, see QUEUE_* below
369 unsigned long queue_flags;
372 * ida allocated id for this queue. Used to index queues from
378 * queue needs bounce pages for pages above this limit
383 * protects queue structures from reentrancy. ->__queue_lock should
384 * _never_ be used directly, it is queue private. always use
387 spinlock_t __queue_lock;
388 spinlock_t *queue_lock;
398 struct kobject mq_kobj;
400 #ifdef CONFIG_BLK_DEV_INTEGRITY
401 struct blk_integrity integrity;
402 #endif /* CONFIG_BLK_DEV_INTEGRITY */
407 unsigned int nr_pending;
413 unsigned long nr_requests; /* Max # of requests */
414 unsigned int nr_congestion_on;
415 unsigned int nr_congestion_off;
416 unsigned int nr_batching;
418 unsigned int dma_drain_size;
419 void *dma_drain_buffer;
420 unsigned int dma_pad_mask;
421 unsigned int dma_alignment;
423 struct blk_queue_tag *queue_tags;
424 struct list_head tag_busy_list;
426 unsigned int nr_sorted;
427 unsigned int in_flight[2];
429 * Number of active block driver functions for which blk_drain_queue()
430 * must wait. Must be incremented around functions that unlock the
431 * queue_lock internally, e.g. scsi_request_fn().
433 unsigned int request_fn_active;
435 unsigned int rq_timeout;
436 struct timer_list timeout;
437 struct work_struct timeout_work;
438 struct list_head timeout_list;
440 struct list_head icq_list;
441 #ifdef CONFIG_BLK_CGROUP
442 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
443 struct blkcg_gq *root_blkg;
444 struct list_head blkg_list;
447 struct queue_limits limits;
452 unsigned int sg_timeout;
453 unsigned int sg_reserved_size;
455 #ifdef CONFIG_BLK_DEV_IO_TRACE
456 struct blk_trace __rcu *blk_trace;
457 struct mutex blk_trace_mutex;
460 * for flush operations
462 struct blk_flush_queue *fq;
464 struct list_head requeue_list;
465 spinlock_t requeue_lock;
466 struct delayed_work requeue_work;
468 struct mutex sysfs_lock;
471 atomic_t mq_freeze_depth;
473 #if defined(CONFIG_BLK_DEV_BSG)
474 bsg_job_fn *bsg_job_fn;
476 struct bsg_class_device bsg_dev;
479 #ifdef CONFIG_BLK_DEV_THROTTLING
481 struct throtl_data *td;
483 struct rcu_head rcu_head;
484 wait_queue_head_t mq_freeze_wq;
485 struct percpu_ref q_usage_counter;
486 struct list_head all_q_node;
488 struct blk_mq_tag_set *tag_set;
489 struct list_head tag_set_list;
490 struct bio_set *bio_split;
492 bool mq_sysfs_init_done;
495 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
496 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
497 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
498 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
499 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
500 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
501 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
502 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
503 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
504 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
505 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
506 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
507 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
508 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
509 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
510 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
511 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
512 #define QUEUE_FLAG_SECERASE 17 /* supports secure erase */
513 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
514 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
515 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
516 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
517 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
518 #define QUEUE_FLAG_WC 23 /* Write back caching */
519 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
520 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
521 #define QUEUE_FLAG_DAX 26 /* device supports DAX */
523 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
524 (1 << QUEUE_FLAG_STACKABLE) | \
525 (1 << QUEUE_FLAG_SAME_COMP) | \
526 (1 << QUEUE_FLAG_ADD_RANDOM))
528 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
529 (1 << QUEUE_FLAG_STACKABLE) | \
530 (1 << QUEUE_FLAG_SAME_COMP) | \
531 (1 << QUEUE_FLAG_POLL))
533 static inline void queue_lockdep_assert_held(struct request_queue *q)
536 lockdep_assert_held(q->queue_lock);
539 static inline void queue_flag_set_unlocked(unsigned int flag,
540 struct request_queue *q)
542 __set_bit(flag, &q->queue_flags);
545 static inline int queue_flag_test_and_clear(unsigned int flag,
546 struct request_queue *q)
548 queue_lockdep_assert_held(q);
550 if (test_bit(flag, &q->queue_flags)) {
551 __clear_bit(flag, &q->queue_flags);
558 static inline int queue_flag_test_and_set(unsigned int flag,
559 struct request_queue *q)
561 queue_lockdep_assert_held(q);
563 if (!test_bit(flag, &q->queue_flags)) {
564 __set_bit(flag, &q->queue_flags);
571 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
573 queue_lockdep_assert_held(q);
574 __set_bit(flag, &q->queue_flags);
577 static inline void queue_flag_clear_unlocked(unsigned int flag,
578 struct request_queue *q)
580 __clear_bit(flag, &q->queue_flags);
583 static inline int queue_in_flight(struct request_queue *q)
585 return q->in_flight[0] + q->in_flight[1];
588 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
590 queue_lockdep_assert_held(q);
591 __clear_bit(flag, &q->queue_flags);
594 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
595 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
596 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
597 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
598 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
599 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
600 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
601 #define blk_queue_noxmerges(q) \
602 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
603 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
604 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
605 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
606 #define blk_queue_stackable(q) \
607 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
608 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
609 #define blk_queue_secure_erase(q) \
610 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
611 #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
613 #define blk_noretry_request(rq) \
614 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
615 REQ_FAILFAST_DRIVER))
617 #define blk_account_rq(rq) \
618 (((rq)->cmd_flags & REQ_STARTED) && \
619 ((rq)->cmd_type == REQ_TYPE_FS))
621 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
622 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
623 /* rq->queuelist of dequeued request must be list_empty() */
624 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
626 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
628 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
631 * Driver can handle struct request, if it either has an old style
632 * request_fn defined, or is blk-mq based.
634 static inline bool queue_is_rq_based(struct request_queue *q)
636 return q->request_fn || q->mq_ops;
639 static inline unsigned int blk_queue_cluster(struct request_queue *q)
641 return q->limits.cluster;
645 * We regard a request as sync, if either a read or a sync write
647 static inline bool rw_is_sync(int op, unsigned int rw_flags)
649 return op == REQ_OP_READ || (rw_flags & REQ_SYNC);
652 static inline bool rq_is_sync(struct request *rq)
654 return rw_is_sync(req_op(rq), rq->cmd_flags);
657 static inline bool blk_rl_full(struct request_list *rl, bool sync)
659 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
661 return rl->flags & flag;
664 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
666 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
671 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
673 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
678 static inline bool rq_mergeable(struct request *rq)
680 if (blk_rq_is_passthrough(rq))
683 if (req_op(rq) == REQ_OP_FLUSH)
686 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
692 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
694 if (bio_data(a) == bio_data(b))
701 * q->prep_rq_fn return values
704 BLKPREP_OK, /* serve it */
705 BLKPREP_KILL, /* fatal error, kill, return -EIO */
706 BLKPREP_DEFER, /* leave on queue */
707 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */
710 extern unsigned long blk_max_low_pfn, blk_max_pfn;
713 * standard bounce addresses:
715 * BLK_BOUNCE_HIGH : bounce all highmem pages
716 * BLK_BOUNCE_ANY : don't bounce anything
717 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
720 #if BITS_PER_LONG == 32
721 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
723 #define BLK_BOUNCE_HIGH -1ULL
725 #define BLK_BOUNCE_ANY (-1ULL)
726 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
729 * default timeout for SG_IO if none specified
731 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
732 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
735 extern int init_emergency_isa_pool(void);
736 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
738 static inline int init_emergency_isa_pool(void)
742 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
745 #endif /* CONFIG_MMU */
751 unsigned long offset;
756 struct req_iterator {
757 struct bvec_iter iter;
761 /* This should not be used directly - use rq_for_each_segment */
762 #define for_each_bio(_bio) \
763 for (; _bio; _bio = _bio->bi_next)
764 #define __rq_for_each_bio(_bio, rq) \
766 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
768 #define rq_for_each_segment(bvl, _rq, _iter) \
769 __rq_for_each_bio(_iter.bio, _rq) \
770 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
772 #define rq_iter_last(bvec, _iter) \
773 (_iter.bio->bi_next == NULL && \
774 bio_iter_last(bvec, _iter.iter))
776 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
777 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
779 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
780 extern void rq_flush_dcache_pages(struct request *rq);
782 static inline void rq_flush_dcache_pages(struct request *rq)
788 #define vfs_msg(sb, level, fmt, ...) \
789 __vfs_msg(sb, level, fmt, ##__VA_ARGS__)
791 #define vfs_msg(sb, level, fmt, ...) \
793 no_printk(fmt, ##__VA_ARGS__); \
794 __vfs_msg(sb, "", " "); \
798 extern int blk_register_queue(struct gendisk *disk);
799 extern void blk_unregister_queue(struct gendisk *disk);
800 extern blk_qc_t generic_make_request(struct bio *bio);
801 extern void blk_rq_init(struct request_queue *q, struct request *rq);
802 extern void blk_put_request(struct request *);
803 extern void __blk_put_request(struct request_queue *, struct request *);
804 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
805 extern void blk_rq_set_block_pc(struct request *);
806 extern void blk_requeue_request(struct request_queue *, struct request *);
807 extern void blk_add_request_payload(struct request *rq, struct page *page,
808 int offset, unsigned int len);
809 extern int blk_lld_busy(struct request_queue *q);
810 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
811 struct bio_set *bs, gfp_t gfp_mask,
812 int (*bio_ctr)(struct bio *, struct bio *, void *),
814 extern void blk_rq_unprep_clone(struct request *rq);
815 extern int blk_insert_cloned_request(struct request_queue *q,
817 extern int blk_rq_append_bio(struct request *rq, struct bio *bio);
818 extern void blk_delay_queue(struct request_queue *, unsigned long);
819 extern void blk_queue_split(struct request_queue *, struct bio **,
821 extern void blk_recount_segments(struct request_queue *, struct bio *);
822 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
823 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
824 unsigned int, void __user *);
825 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
826 unsigned int, void __user *);
827 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
828 struct scsi_ioctl_command __user *);
830 extern int blk_queue_enter(struct request_queue *q, bool nowait);
831 extern void blk_queue_exit(struct request_queue *q);
832 extern void blk_start_queue(struct request_queue *q);
833 extern void blk_start_queue_async(struct request_queue *q);
834 extern void blk_stop_queue(struct request_queue *q);
835 extern void blk_sync_queue(struct request_queue *q);
836 extern void __blk_stop_queue(struct request_queue *q);
837 extern void __blk_run_queue(struct request_queue *q);
838 extern void __blk_run_queue_uncond(struct request_queue *q);
839 extern void blk_run_queue(struct request_queue *);
840 extern void blk_run_queue_async(struct request_queue *q);
841 extern int blk_rq_map_user(struct request_queue *, struct request *,
842 struct rq_map_data *, void __user *, unsigned long,
844 extern int blk_rq_unmap_user(struct bio *);
845 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
846 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
847 struct rq_map_data *, const struct iov_iter *,
849 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
850 struct request *, int);
851 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
852 struct request *, int, rq_end_io_fn *);
854 bool blk_poll(struct request_queue *q, blk_qc_t cookie);
856 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
858 return bdev->bd_disk->queue; /* this is never NULL */
862 * The basic unit of block I/O is a sector. It is used in a number of contexts
863 * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
864 * bytes. Variables of type sector_t represent an offset or size that is a
865 * multiple of 512 bytes. Hence these two constants.
868 #define SECTOR_SHIFT 9
871 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
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) >> SECTOR_SHIFT;
904 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
906 return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
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,
914 UINT_MAX >> SECTOR_SHIFT);
916 if (unlikely(op == REQ_OP_WRITE_SAME))
917 return q->limits.max_write_same_sectors;
919 return q->limits.max_sectors;
923 * Return maximum size of a request at given offset. Only valid for
924 * file system requests.
926 static inline unsigned int blk_max_size_offset(struct request_queue *q,
929 if (!q->limits.chunk_sectors)
930 return q->limits.max_sectors;
932 return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
933 (offset & (q->limits.chunk_sectors - 1))));
936 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
939 struct request_queue *q = rq->q;
941 if (blk_rq_is_passthrough(rq))
942 return q->limits.max_hw_sectors;
944 if (!q->limits.chunk_sectors ||
945 req_op(rq) == REQ_OP_DISCARD ||
946 req_op(rq) == REQ_OP_SECURE_ERASE)
947 return blk_queue_get_max_sectors(q, req_op(rq));
949 return min(blk_max_size_offset(q, offset),
950 blk_queue_get_max_sectors(q, req_op(rq)));
953 static inline unsigned int blk_rq_count_bios(struct request *rq)
955 unsigned int nr_bios = 0;
958 __rq_for_each_bio(bio, rq)
965 * Request issue related functions.
967 extern struct request *blk_peek_request(struct request_queue *q);
968 extern void blk_start_request(struct request *rq);
969 extern struct request *blk_fetch_request(struct request_queue *q);
972 * Request completion related functions.
974 * blk_update_request() completes given number of bytes and updates
975 * the request without completing it.
977 * blk_end_request() and friends. __blk_end_request() must be called
978 * with the request queue spinlock acquired.
980 * Several drivers define their own end_request and call
981 * blk_end_request() for parts of the original function.
982 * This prevents code duplication in drivers.
984 extern bool blk_update_request(struct request *rq, int error,
985 unsigned int nr_bytes);
986 extern void blk_finish_request(struct request *rq, int error);
987 extern bool blk_end_request(struct request *rq, int error,
988 unsigned int nr_bytes);
989 extern void blk_end_request_all(struct request *rq, int error);
990 extern bool blk_end_request_cur(struct request *rq, int error);
991 extern bool blk_end_request_err(struct request *rq, int error);
992 extern bool __blk_end_request(struct request *rq, int error,
993 unsigned int nr_bytes);
994 extern void __blk_end_request_all(struct request *rq, int error);
995 extern bool __blk_end_request_cur(struct request *rq, int error);
996 extern bool __blk_end_request_err(struct request *rq, int error);
998 extern void blk_complete_request(struct request *);
999 extern void __blk_complete_request(struct request *);
1000 extern void blk_abort_request(struct request *);
1001 extern void blk_unprep_request(struct request *);
1004 * Access functions for manipulating queue properties
1006 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
1007 spinlock_t *lock, int node_id);
1008 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
1009 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
1010 request_fn_proc *, spinlock_t *);
1011 extern void blk_cleanup_queue(struct request_queue *);
1012 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1013 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1014 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1015 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1016 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1017 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1018 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1019 unsigned int max_discard_sectors);
1020 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1021 unsigned int max_write_same_sectors);
1022 extern void blk_queue_logical_block_size(struct request_queue *, unsigned int);
1023 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1024 extern void blk_queue_alignment_offset(struct request_queue *q,
1025 unsigned int alignment);
1026 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1027 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1028 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1029 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1030 extern void blk_set_default_limits(struct queue_limits *lim);
1031 extern void blk_set_stacking_limits(struct queue_limits *lim);
1032 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1034 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1036 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1038 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1039 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1040 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1041 extern int blk_queue_dma_drain(struct request_queue *q,
1042 dma_drain_needed_fn *dma_drain_needed,
1043 void *buf, unsigned int size);
1044 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1045 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1046 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1047 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1048 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1049 extern void blk_queue_dma_alignment(struct request_queue *, int);
1050 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1051 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1052 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1053 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1054 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1055 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1056 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1058 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1059 extern void blk_dump_rq_flags(struct request *, char *);
1060 extern long nr_blockdev_pages(void);
1062 bool __must_check blk_get_queue(struct request_queue *);
1063 struct request_queue *blk_alloc_queue(gfp_t);
1064 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1065 extern void blk_put_queue(struct request_queue *);
1066 extern void blk_set_queue_dying(struct request_queue *);
1069 * block layer runtime pm functions
1072 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1073 extern int blk_pre_runtime_suspend(struct request_queue *q);
1074 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1075 extern void blk_pre_runtime_resume(struct request_queue *q);
1076 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1077 extern void blk_set_runtime_active(struct request_queue *q);
1079 static inline void blk_pm_runtime_init(struct request_queue *q,
1080 struct device *dev) {}
1081 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1085 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1086 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1087 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1088 static inline void blk_set_runtime_active(struct request_queue *q) {}
1092 * blk_plug permits building a queue of related requests by holding the I/O
1093 * fragments for a short period. This allows merging of sequential requests
1094 * into single larger request. As the requests are moved from a per-task list to
1095 * the device's request_queue in a batch, this results in improved scalability
1096 * as the lock contention for request_queue lock is reduced.
1098 * It is ok not to disable preemption when adding the request to the plug list
1099 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1100 * the plug list when the task sleeps by itself. For details, please see
1101 * schedule() where blk_schedule_flush_plug() is called.
1104 struct list_head list; /* requests */
1105 struct list_head mq_list; /* blk-mq requests */
1106 struct list_head cb_list; /* md requires an unplug callback */
1108 #define BLK_MAX_REQUEST_COUNT 16
1111 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1112 struct blk_plug_cb {
1113 struct list_head list;
1114 blk_plug_cb_fn callback;
1117 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1118 void *data, int size);
1119 extern void blk_start_plug(struct blk_plug *);
1120 extern void blk_finish_plug(struct blk_plug *);
1121 extern void blk_flush_plug_list(struct blk_plug *, bool);
1123 static inline void blk_flush_plug(struct task_struct *tsk)
1125 struct blk_plug *plug = tsk->plug;
1128 blk_flush_plug_list(plug, false);
1131 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1133 struct blk_plug *plug = tsk->plug;
1136 blk_flush_plug_list(plug, true);
1139 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1141 struct blk_plug *plug = tsk->plug;
1144 (!list_empty(&plug->list) ||
1145 !list_empty(&plug->mq_list) ||
1146 !list_empty(&plug->cb_list));
1152 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1153 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1154 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1155 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1156 extern void blk_queue_free_tags(struct request_queue *);
1157 extern int blk_queue_resize_tags(struct request_queue *, int);
1158 extern void blk_queue_invalidate_tags(struct request_queue *);
1159 extern struct blk_queue_tag *blk_init_tags(int, int);
1160 extern void blk_free_tags(struct blk_queue_tag *);
1162 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1165 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1167 return bqt->tag_index[tag];
1171 #define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */
1172 #define BLKDEV_DISCARD_ZERO (1 << 1) /* must reliably zero data */
1174 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1175 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1176 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1177 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1178 sector_t nr_sects, gfp_t gfp_mask, int flags,
1180 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1181 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1182 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1183 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1184 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1185 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1187 return blkdev_issue_discard(sb->s_bdev,
1188 block << (sb->s_blocksize_bits -
1190 nr_blocks << (sb->s_blocksize_bits -
1194 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1195 sector_t nr_blocks, gfp_t gfp_mask)
1197 return blkdev_issue_zeroout(sb->s_bdev,
1198 block << (sb->s_blocksize_bits -
1200 nr_blocks << (sb->s_blocksize_bits -
1205 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1207 enum blk_default_limits {
1208 BLK_MAX_SEGMENTS = 128,
1209 BLK_SAFE_MAX_SECTORS = 255,
1210 BLK_DEF_MAX_SECTORS = 2560,
1211 BLK_MAX_SEGMENT_SIZE = 65536,
1212 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1215 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1217 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1219 return q->limits.bounce_pfn;
1222 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1224 return q->limits.seg_boundary_mask;
1227 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1229 return q->limits.virt_boundary_mask;
1232 static inline unsigned int queue_max_sectors(struct request_queue *q)
1234 return q->limits.max_sectors;
1237 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1239 return q->limits.max_hw_sectors;
1242 static inline unsigned short queue_max_segments(struct request_queue *q)
1244 return q->limits.max_segments;
1247 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1249 return q->limits.max_segment_size;
1252 static inline unsigned queue_logical_block_size(struct request_queue *q)
1256 if (q && q->limits.logical_block_size)
1257 retval = q->limits.logical_block_size;
1262 static inline unsigned int bdev_logical_block_size(struct block_device *bdev)
1264 return queue_logical_block_size(bdev_get_queue(bdev));
1267 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1269 return q->limits.physical_block_size;
1272 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1274 return queue_physical_block_size(bdev_get_queue(bdev));
1277 static inline unsigned int queue_io_min(struct request_queue *q)
1279 return q->limits.io_min;
1282 static inline int bdev_io_min(struct block_device *bdev)
1284 return queue_io_min(bdev_get_queue(bdev));
1287 static inline unsigned int queue_io_opt(struct request_queue *q)
1289 return q->limits.io_opt;
1292 static inline int bdev_io_opt(struct block_device *bdev)
1294 return queue_io_opt(bdev_get_queue(bdev));
1297 static inline int queue_alignment_offset(struct request_queue *q)
1299 if (q->limits.misaligned)
1302 return q->limits.alignment_offset;
1305 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1307 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1308 unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1311 return (granularity + lim->alignment_offset - alignment) % granularity;
1314 static inline int bdev_alignment_offset(struct block_device *bdev)
1316 struct request_queue *q = bdev_get_queue(bdev);
1318 if (q->limits.misaligned)
1321 if (bdev != bdev->bd_contains)
1322 return bdev->bd_part->alignment_offset;
1324 return q->limits.alignment_offset;
1327 static inline int queue_discard_alignment(struct request_queue *q)
1329 if (q->limits.discard_misaligned)
1332 return q->limits.discard_alignment;
1335 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1337 unsigned int alignment, granularity, offset;
1339 if (!lim->max_discard_sectors)
1342 /* Why are these in bytes, not sectors? */
1343 alignment = lim->discard_alignment >> SECTOR_SHIFT;
1344 granularity = lim->discard_granularity >> SECTOR_SHIFT;
1348 /* Offset of the partition start in 'granularity' sectors */
1349 offset = sector_div(sector, granularity);
1351 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1352 offset = (granularity + alignment - offset) % granularity;
1354 /* Turn it back into bytes, gaah */
1355 return offset << SECTOR_SHIFT;
1358 static inline int bdev_discard_alignment(struct block_device *bdev)
1360 struct request_queue *q = bdev_get_queue(bdev);
1362 if (bdev != bdev->bd_contains)
1363 return bdev->bd_part->discard_alignment;
1365 return q->limits.discard_alignment;
1368 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1370 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1376 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1378 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1381 static inline unsigned int bdev_write_same(struct block_device *bdev)
1383 struct request_queue *q = bdev_get_queue(bdev);
1386 return q->limits.max_write_same_sectors;
1391 static inline int queue_dma_alignment(struct request_queue *q)
1393 return q ? q->dma_alignment : 511;
1396 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1399 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1400 return !(addr & alignment) && !(len & alignment);
1403 /* assumes size > 256 */
1404 static inline unsigned int blksize_bits(unsigned int size)
1406 unsigned int bits = 8;
1410 } while (size > 256);
1414 static inline unsigned int block_size(struct block_device *bdev)
1416 return bdev->bd_block_size;
1419 static inline bool queue_flush_queueable(struct request_queue *q)
1421 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags);
1424 typedef struct {struct page *v;} Sector;
1426 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1428 static inline void put_dev_sector(Sector p)
1433 static inline bool __bvec_gap_to_prev(struct request_queue *q,
1434 struct bio_vec *bprv, unsigned int offset)
1437 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1441 * Check if adding a bio_vec after bprv with offset would create a gap in
1442 * the SG list. Most drivers don't care about this, but some do.
1444 static inline bool bvec_gap_to_prev(struct request_queue *q,
1445 struct bio_vec *bprv, unsigned int offset)
1447 if (!queue_virt_boundary(q))
1449 return __bvec_gap_to_prev(q, bprv, offset);
1452 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1455 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1456 struct bio_vec pb, nb;
1458 bio_get_last_bvec(prev, &pb);
1459 bio_get_first_bvec(next, &nb);
1461 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1467 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1469 return bio_will_gap(req->q, req->biotail, bio);
1472 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1474 return bio_will_gap(req->q, bio, req->bio);
1477 int kblockd_schedule_work(struct work_struct *work);
1478 int kblockd_schedule_work_on(int cpu, struct work_struct *work);
1479 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1480 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1482 #ifdef CONFIG_BLK_CGROUP
1484 * This should not be using sched_clock(). A real patch is in progress
1485 * to fix this up, until that is in place we need to disable preemption
1486 * around sched_clock() in this function and set_io_start_time_ns().
1488 static inline void set_start_time_ns(struct request *req)
1491 req->start_time_ns = sched_clock();
1495 static inline void set_io_start_time_ns(struct request *req)
1498 req->io_start_time_ns = sched_clock();
1502 static inline uint64_t rq_start_time_ns(struct request *req)
1504 return req->start_time_ns;
1507 static inline uint64_t rq_io_start_time_ns(struct request *req)
1509 return req->io_start_time_ns;
1512 static inline void set_start_time_ns(struct request *req) {}
1513 static inline void set_io_start_time_ns(struct request *req) {}
1514 static inline uint64_t rq_start_time_ns(struct request *req)
1518 static inline uint64_t rq_io_start_time_ns(struct request *req)
1524 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1525 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1526 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1527 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1529 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1531 enum blk_integrity_flags {
1532 BLK_INTEGRITY_VERIFY = 1 << 0,
1533 BLK_INTEGRITY_GENERATE = 1 << 1,
1534 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1535 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1538 struct blk_integrity_iter {
1542 unsigned int data_size;
1543 unsigned short interval;
1544 const char *disk_name;
1547 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1549 struct blk_integrity_profile {
1550 integrity_processing_fn *generate_fn;
1551 integrity_processing_fn *verify_fn;
1555 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1556 extern void blk_integrity_unregister(struct gendisk *);
1557 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1558 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1559 struct scatterlist *);
1560 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1561 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1563 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1566 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1568 struct blk_integrity *bi = &disk->queue->integrity;
1577 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1579 return blk_get_integrity(bdev->bd_disk);
1582 static inline bool blk_integrity_rq(struct request *rq)
1584 return rq->cmd_flags & REQ_INTEGRITY;
1587 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1590 q->limits.max_integrity_segments = segs;
1593 static inline unsigned short
1594 queue_max_integrity_segments(struct request_queue *q)
1596 return q->limits.max_integrity_segments;
1599 static inline bool integrity_req_gap_back_merge(struct request *req,
1602 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1603 struct bio_integrity_payload *bip_next = bio_integrity(next);
1605 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1606 bip_next->bip_vec[0].bv_offset);
1609 static inline bool integrity_req_gap_front_merge(struct request *req,
1612 struct bio_integrity_payload *bip = bio_integrity(bio);
1613 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1615 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1616 bip_next->bip_vec[0].bv_offset);
1619 #else /* CONFIG_BLK_DEV_INTEGRITY */
1622 struct block_device;
1624 struct blk_integrity;
1626 static inline int blk_integrity_rq(struct request *rq)
1630 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1635 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1637 struct scatterlist *s)
1641 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1645 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1649 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1653 static inline void blk_integrity_register(struct gendisk *d,
1654 struct blk_integrity *b)
1657 static inline void blk_integrity_unregister(struct gendisk *d)
1660 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1664 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1668 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1674 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1681 static inline bool integrity_req_gap_back_merge(struct request *req,
1686 static inline bool integrity_req_gap_front_merge(struct request *req,
1692 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1695 * struct blk_dax_ctl - control and output parameters for ->direct_access
1696 * @sector: (input) offset relative to a block_device
1697 * @addr: (output) kernel virtual address for @sector populated by driver
1698 * @pfn: (output) page frame number for @addr populated by driver
1699 * @size: (input) number of bytes requested
1701 struct blk_dax_ctl {
1708 struct block_device_operations {
1709 int (*open) (struct block_device *, fmode_t);
1710 void (*release) (struct gendisk *, fmode_t);
1711 int (*rw_page)(struct block_device *, sector_t, struct page *, bool);
1712 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1713 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1714 long (*direct_access)(struct block_device *, sector_t, void **, pfn_t *,
1716 unsigned int (*check_events) (struct gendisk *disk,
1717 unsigned int clearing);
1718 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1719 int (*media_changed) (struct gendisk *);
1720 void (*unlock_native_capacity) (struct gendisk *);
1721 int (*revalidate_disk) (struct gendisk *);
1722 int (*getgeo)(struct block_device *, struct hd_geometry *);
1723 /* this callback is with swap_lock and sometimes page table lock held */
1724 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1725 struct module *owner;
1726 const struct pr_ops *pr_ops;
1729 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1731 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1732 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1733 struct writeback_control *);
1734 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *);
1735 extern int bdev_dax_supported(struct super_block *, int);
1736 extern bool bdev_dax_capable(struct block_device *);
1737 #else /* CONFIG_BLOCK */
1739 struct block_device;
1742 * stubs for when the block layer is configured out
1744 #define buffer_heads_over_limit 0
1746 static inline long nr_blockdev_pages(void)
1754 static inline void blk_start_plug(struct blk_plug *plug)
1758 static inline void blk_finish_plug(struct blk_plug *plug)
1762 static inline void blk_flush_plug(struct task_struct *task)
1766 static inline void blk_schedule_flush_plug(struct task_struct *task)
1771 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1776 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1777 sector_t *error_sector)
1782 #endif /* CONFIG_BLOCK */