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
51 typedef void (rq_end_io_fn
)(struct request
*, int);
53 #define BLK_RL_SYNCFULL (1U << 0)
54 #define BLK_RL_ASYNCFULL (1U << 1)
57 struct request_queue
*q
; /* the queue this rl belongs to */
58 #ifdef CONFIG_BLK_CGROUP
59 struct blkcg_gq
*blkg
; /* blkg this request pool belongs to */
62 * count[], starved[], and wait[] are indexed by
63 * BLK_RW_SYNC/BLK_RW_ASYNC
68 wait_queue_head_t wait
[2];
73 * request command types
75 enum rq_cmd_type_bits
{
76 REQ_TYPE_FS
= 1, /* fs request */
77 REQ_TYPE_BLOCK_PC
, /* scsi command */
78 REQ_TYPE_DRV_PRIV
, /* driver defined types from here */
81 #define BLK_MAX_CDB 16
84 * Try to put the fields that are referenced together in the same cacheline.
86 * If you modify this structure, make sure to update blk_rq_init() and
87 * especially blk_mq_rq_ctx_init() to take care of the added fields.
90 struct list_head queuelist
;
92 struct call_single_data csd
;
93 unsigned long fifo_time
;
96 struct request_queue
*q
;
97 struct blk_mq_ctx
*mq_ctx
;
101 unsigned long atomic_flags
;
105 /* the following two fields are internal, NEVER access directly */
106 unsigned int __data_len
; /* total data len */
107 sector_t __sector
; /* sector cursor */
113 * The hash is used inside the scheduler, and killed once the
114 * request reaches the dispatch list. The ipi_list is only used
115 * to queue the request for softirq completion, which is long
116 * after the request has been unhashed (and even removed from
117 * the dispatch list).
120 struct hlist_node hash
; /* merge hash */
121 struct list_head ipi_list
;
125 * The rb_node is only used inside the io scheduler, requests
126 * are pruned when moved to the dispatch queue. So let the
127 * completion_data share space with the rb_node.
130 struct rb_node rb_node
; /* sort/lookup */
131 void *completion_data
;
135 * Three pointers are available for the IO schedulers, if they need
136 * more they have to dynamically allocate it. Flush requests are
137 * never put on the IO scheduler. So let the flush fields share
138 * space with the elevator data.
148 struct list_head list
;
149 rq_end_io_fn
*saved_end_io
;
153 struct gendisk
*rq_disk
;
154 struct hd_struct
*part
;
155 unsigned long start_time
;
156 #ifdef CONFIG_BLK_CGROUP
157 struct request_list
*rl
; /* rl this rq is alloced from */
158 unsigned long long start_time_ns
;
159 unsigned long long io_start_time_ns
; /* when passed to hardware */
161 /* Number of scatter-gather DMA addr+len pairs after
162 * physical address coalescing is performed.
164 unsigned short nr_phys_segments
;
165 #if defined(CONFIG_BLK_DEV_INTEGRITY)
166 unsigned short nr_integrity_segments
;
169 unsigned short ioprio
;
171 void *special
; /* opaque pointer available for LLD use */
177 * when request is used as a packet command carrier
179 unsigned char __cmd
[BLK_MAX_CDB
];
181 unsigned short cmd_len
;
183 unsigned int extra_len
; /* length of alignment and padding */
184 unsigned int sense_len
;
185 unsigned int resid_len
; /* residual count */
188 unsigned long deadline
;
189 struct list_head timeout_list
;
190 unsigned int timeout
;
194 * completion callback.
196 rq_end_io_fn
*end_io
;
200 struct request
*next_rq
;
203 static inline unsigned short req_get_ioprio(struct request
*req
)
208 #include <linux/elevator.h>
210 struct blk_queue_ctx
;
212 typedef void (request_fn_proc
) (struct request_queue
*q
);
213 typedef blk_qc_t (make_request_fn
) (struct request_queue
*q
, struct bio
*bio
);
214 typedef int (prep_rq_fn
) (struct request_queue
*, struct request
*);
215 typedef void (unprep_rq_fn
) (struct request_queue
*, struct request
*);
218 typedef void (softirq_done_fn
)(struct request
*);
219 typedef int (dma_drain_needed_fn
)(struct request
*);
220 typedef int (lld_busy_fn
) (struct request_queue
*q
);
221 typedef int (bsg_job_fn
) (struct bsg_job
*);
223 enum blk_eh_timer_return
{
229 typedef enum blk_eh_timer_return (rq_timed_out_fn
)(struct request
*);
231 enum blk_queue_state
{
236 struct blk_queue_tag
{
237 struct request
**tag_index
; /* map of busy tags */
238 unsigned long *tag_map
; /* bit map of free/busy tags */
239 int busy
; /* current depth */
240 int max_depth
; /* what we will send to device */
241 int real_max_depth
; /* what the array can hold */
242 atomic_t refcnt
; /* map can be shared */
243 int alloc_policy
; /* tag allocation policy */
244 int next_tag
; /* next tag */
246 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
247 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
249 #define BLK_SCSI_MAX_CMDS (256)
250 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
252 struct queue_limits
{
253 unsigned long bounce_pfn
;
254 unsigned long seg_boundary_mask
;
255 unsigned long virt_boundary_mask
;
257 unsigned int max_hw_sectors
;
258 unsigned int max_dev_sectors
;
259 unsigned int chunk_sectors
;
260 unsigned int max_sectors
;
261 unsigned int max_segment_size
;
262 unsigned int physical_block_size
;
263 unsigned int alignment_offset
;
266 unsigned int max_discard_sectors
;
267 unsigned int max_hw_discard_sectors
;
268 unsigned int max_write_same_sectors
;
269 unsigned int discard_granularity
;
270 unsigned int discard_alignment
;
272 unsigned short logical_block_size
;
273 unsigned short max_segments
;
274 unsigned short max_integrity_segments
;
276 unsigned char misaligned
;
277 unsigned char discard_misaligned
;
278 unsigned char cluster
;
279 unsigned char discard_zeroes_data
;
280 unsigned char raid_partial_stripes_expensive
;
283 struct request_queue
{
285 * Together with queue_head for cacheline sharing
287 struct list_head queue_head
;
288 struct request
*last_merge
;
289 struct elevator_queue
*elevator
;
290 int nr_rqs
[2]; /* # allocated [a]sync rqs */
291 int nr_rqs_elvpriv
; /* # allocated rqs w/ elvpriv */
294 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
295 * is used, root blkg allocates from @q->root_rl and all other
296 * blkgs from their own blkg->rl. Which one to use should be
297 * determined using bio_request_list().
299 struct request_list root_rl
;
301 request_fn_proc
*request_fn
;
302 make_request_fn
*make_request_fn
;
303 prep_rq_fn
*prep_rq_fn
;
304 unprep_rq_fn
*unprep_rq_fn
;
305 softirq_done_fn
*softirq_done_fn
;
306 rq_timed_out_fn
*rq_timed_out_fn
;
307 dma_drain_needed_fn
*dma_drain_needed
;
308 lld_busy_fn
*lld_busy_fn
;
310 struct blk_mq_ops
*mq_ops
;
312 unsigned int *mq_map
;
315 struct blk_mq_ctx __percpu
*queue_ctx
;
316 unsigned int nr_queues
;
318 /* hw dispatch queues */
319 struct blk_mq_hw_ctx
**queue_hw_ctx
;
320 unsigned int nr_hw_queues
;
323 * Dispatch queue sorting
326 struct request
*boundary_rq
;
329 * Delayed queue handling
331 struct delayed_work delay_work
;
333 struct backing_dev_info backing_dev_info
;
336 * The queue owner gets to use this for whatever they like.
337 * ll_rw_blk doesn't touch it.
342 * various queue flags, see QUEUE_* below
344 unsigned long queue_flags
;
347 * ida allocated id for this queue. Used to index queues from
353 * queue needs bounce pages for pages above this limit
358 * protects queue structures from reentrancy. ->__queue_lock should
359 * _never_ be used directly, it is queue private. always use
362 spinlock_t __queue_lock
;
363 spinlock_t
*queue_lock
;
373 struct kobject mq_kobj
;
375 #ifdef CONFIG_BLK_DEV_INTEGRITY
376 struct blk_integrity integrity
;
377 #endif /* CONFIG_BLK_DEV_INTEGRITY */
382 unsigned int nr_pending
;
388 unsigned long nr_requests
; /* Max # of requests */
389 unsigned int nr_congestion_on
;
390 unsigned int nr_congestion_off
;
391 unsigned int nr_batching
;
393 unsigned int dma_drain_size
;
394 void *dma_drain_buffer
;
395 unsigned int dma_pad_mask
;
396 unsigned int dma_alignment
;
398 struct blk_queue_tag
*queue_tags
;
399 struct list_head tag_busy_list
;
401 unsigned int nr_sorted
;
402 unsigned int in_flight
[2];
404 * Number of active block driver functions for which blk_drain_queue()
405 * must wait. Must be incremented around functions that unlock the
406 * queue_lock internally, e.g. scsi_request_fn().
408 unsigned int request_fn_active
;
410 unsigned int rq_timeout
;
411 struct timer_list timeout
;
412 struct work_struct timeout_work
;
413 struct list_head timeout_list
;
415 struct list_head icq_list
;
416 #ifdef CONFIG_BLK_CGROUP
417 DECLARE_BITMAP (blkcg_pols
, BLKCG_MAX_POLS
);
418 struct blkcg_gq
*root_blkg
;
419 struct list_head blkg_list
;
422 struct queue_limits limits
;
427 unsigned int sg_timeout
;
428 unsigned int sg_reserved_size
;
430 #ifdef CONFIG_BLK_DEV_IO_TRACE
431 struct blk_trace
*blk_trace
;
434 * for flush operations
436 struct blk_flush_queue
*fq
;
438 struct list_head requeue_list
;
439 spinlock_t requeue_lock
;
440 struct work_struct requeue_work
;
442 struct mutex sysfs_lock
;
445 atomic_t mq_freeze_depth
;
447 #if defined(CONFIG_BLK_DEV_BSG)
448 bsg_job_fn
*bsg_job_fn
;
450 struct bsg_class_device bsg_dev
;
453 #ifdef CONFIG_BLK_DEV_THROTTLING
455 struct throtl_data
*td
;
457 struct rcu_head rcu_head
;
458 wait_queue_head_t mq_freeze_wq
;
459 struct percpu_ref q_usage_counter
;
460 struct list_head all_q_node
;
462 struct blk_mq_tag_set
*tag_set
;
463 struct list_head tag_set_list
;
464 struct bio_set
*bio_split
;
466 bool mq_sysfs_init_done
;
469 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
470 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
471 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
472 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
473 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
474 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
475 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
476 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
477 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
478 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
479 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
480 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
481 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
482 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
483 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
484 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
485 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
486 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
487 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
488 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
489 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
490 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
491 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
492 #define QUEUE_FLAG_WC 23 /* Write back caching */
493 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
494 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
496 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
497 (1 << QUEUE_FLAG_STACKABLE) | \
498 (1 << QUEUE_FLAG_SAME_COMP) | \
499 (1 << QUEUE_FLAG_ADD_RANDOM))
501 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
502 (1 << QUEUE_FLAG_STACKABLE) | \
503 (1 << QUEUE_FLAG_SAME_COMP) | \
504 (1 << QUEUE_FLAG_POLL))
506 static inline void queue_lockdep_assert_held(struct request_queue
*q
)
509 lockdep_assert_held(q
->queue_lock
);
512 static inline void queue_flag_set_unlocked(unsigned int flag
,
513 struct request_queue
*q
)
515 __set_bit(flag
, &q
->queue_flags
);
518 static inline int queue_flag_test_and_clear(unsigned int flag
,
519 struct request_queue
*q
)
521 queue_lockdep_assert_held(q
);
523 if (test_bit(flag
, &q
->queue_flags
)) {
524 __clear_bit(flag
, &q
->queue_flags
);
531 static inline int queue_flag_test_and_set(unsigned int flag
,
532 struct request_queue
*q
)
534 queue_lockdep_assert_held(q
);
536 if (!test_bit(flag
, &q
->queue_flags
)) {
537 __set_bit(flag
, &q
->queue_flags
);
544 static inline void queue_flag_set(unsigned int flag
, struct request_queue
*q
)
546 queue_lockdep_assert_held(q
);
547 __set_bit(flag
, &q
->queue_flags
);
550 static inline void queue_flag_clear_unlocked(unsigned int flag
,
551 struct request_queue
*q
)
553 __clear_bit(flag
, &q
->queue_flags
);
556 static inline int queue_in_flight(struct request_queue
*q
)
558 return q
->in_flight
[0] + q
->in_flight
[1];
561 static inline void queue_flag_clear(unsigned int flag
, struct request_queue
*q
)
563 queue_lockdep_assert_held(q
);
564 __clear_bit(flag
, &q
->queue_flags
);
567 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
568 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
569 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
570 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
571 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
572 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
573 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
574 #define blk_queue_noxmerges(q) \
575 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
576 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
577 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
578 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
579 #define blk_queue_stackable(q) \
580 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
581 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
582 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
583 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
585 #define blk_noretry_request(rq) \
586 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
587 REQ_FAILFAST_DRIVER))
589 #define blk_account_rq(rq) \
590 (((rq)->cmd_flags & REQ_STARTED) && \
591 ((rq)->cmd_type == REQ_TYPE_FS))
593 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
594 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
595 /* rq->queuelist of dequeued request must be list_empty() */
596 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
598 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
600 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1))
603 * Driver can handle struct request, if it either has an old style
604 * request_fn defined, or is blk-mq based.
606 static inline bool queue_is_rq_based(struct request_queue
*q
)
608 return q
->request_fn
|| q
->mq_ops
;
611 static inline unsigned int blk_queue_cluster(struct request_queue
*q
)
613 return q
->limits
.cluster
;
617 * We regard a request as sync, if either a read or a sync write
619 static inline bool rw_is_sync(unsigned int rw_flags
)
621 return !(rw_flags
& REQ_WRITE
) || (rw_flags
& REQ_SYNC
);
624 static inline bool rq_is_sync(struct request
*rq
)
626 return rw_is_sync(rq
->cmd_flags
);
629 static inline bool blk_rl_full(struct request_list
*rl
, bool sync
)
631 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
633 return rl
->flags
& flag
;
636 static inline void blk_set_rl_full(struct request_list
*rl
, bool sync
)
638 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
643 static inline void blk_clear_rl_full(struct request_list
*rl
, bool sync
)
645 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
650 static inline bool rq_mergeable(struct request
*rq
)
652 if (rq
->cmd_type
!= REQ_TYPE_FS
)
655 if (rq
->cmd_flags
& REQ_NOMERGE_FLAGS
)
661 static inline bool blk_check_merge_flags(unsigned int flags1
,
664 if ((flags1
& REQ_DISCARD
) != (flags2
& REQ_DISCARD
))
667 if ((flags1
& REQ_SECURE
) != (flags2
& REQ_SECURE
))
670 if ((flags1
& REQ_WRITE_SAME
) != (flags2
& REQ_WRITE_SAME
))
676 static inline bool blk_write_same_mergeable(struct bio
*a
, struct bio
*b
)
678 if (bio_data(a
) == bio_data(b
))
685 * q->prep_rq_fn return values
688 BLKPREP_OK
, /* serve it */
689 BLKPREP_KILL
, /* fatal error, kill, return -EIO */
690 BLKPREP_DEFER
, /* leave on queue */
691 BLKPREP_INVALID
, /* invalid command, kill, return -EREMOTEIO */
694 extern unsigned long blk_max_low_pfn
, blk_max_pfn
;
697 * standard bounce addresses:
699 * BLK_BOUNCE_HIGH : bounce all highmem pages
700 * BLK_BOUNCE_ANY : don't bounce anything
701 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
704 #if BITS_PER_LONG == 32
705 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
707 #define BLK_BOUNCE_HIGH -1ULL
709 #define BLK_BOUNCE_ANY (-1ULL)
710 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
713 * default timeout for SG_IO if none specified
715 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
716 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
719 extern int init_emergency_isa_pool(void);
720 extern void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
);
722 static inline int init_emergency_isa_pool(void)
726 static inline void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
)
729 #endif /* CONFIG_MMU */
735 unsigned long offset
;
740 struct req_iterator
{
741 struct bvec_iter iter
;
745 /* This should not be used directly - use rq_for_each_segment */
746 #define for_each_bio(_bio) \
747 for (; _bio; _bio = _bio->bi_next)
748 #define __rq_for_each_bio(_bio, rq) \
750 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
752 #define rq_for_each_segment(bvl, _rq, _iter) \
753 __rq_for_each_bio(_iter.bio, _rq) \
754 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
756 #define rq_iter_last(bvec, _iter) \
757 (_iter.bio->bi_next == NULL && \
758 bio_iter_last(bvec, _iter.iter))
760 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
761 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
763 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
764 extern void rq_flush_dcache_pages(struct request
*rq
);
766 static inline void rq_flush_dcache_pages(struct request
*rq
)
771 extern int blk_register_queue(struct gendisk
*disk
);
772 extern void blk_unregister_queue(struct gendisk
*disk
);
773 extern blk_qc_t
generic_make_request(struct bio
*bio
);
774 extern void blk_rq_init(struct request_queue
*q
, struct request
*rq
);
775 extern void blk_put_request(struct request
*);
776 extern void __blk_put_request(struct request_queue
*, struct request
*);
777 extern struct request
*blk_get_request(struct request_queue
*, int, gfp_t
);
778 extern struct request
*blk_make_request(struct request_queue
*, struct bio
*,
780 extern void blk_rq_set_block_pc(struct request
*);
781 extern void blk_requeue_request(struct request_queue
*, struct request
*);
782 extern void blk_add_request_payload(struct request
*rq
, struct page
*page
,
783 int offset
, unsigned int len
);
784 extern int blk_lld_busy(struct request_queue
*q
);
785 extern int blk_rq_prep_clone(struct request
*rq
, struct request
*rq_src
,
786 struct bio_set
*bs
, gfp_t gfp_mask
,
787 int (*bio_ctr
)(struct bio
*, struct bio
*, void *),
789 extern void blk_rq_unprep_clone(struct request
*rq
);
790 extern int blk_insert_cloned_request(struct request_queue
*q
,
792 extern void blk_delay_queue(struct request_queue
*, unsigned long);
793 extern void blk_queue_split(struct request_queue
*, struct bio
**,
795 extern void blk_recount_segments(struct request_queue
*, struct bio
*);
796 extern int scsi_verify_blk_ioctl(struct block_device
*, unsigned int);
797 extern int scsi_cmd_blk_ioctl(struct block_device
*, fmode_t
,
798 unsigned int, void __user
*);
799 extern int scsi_cmd_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
800 unsigned int, void __user
*);
801 extern int sg_scsi_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
802 struct scsi_ioctl_command __user
*);
804 extern int blk_queue_enter(struct request_queue
*q
, bool nowait
);
805 extern void blk_queue_exit(struct request_queue
*q
);
806 extern void blk_start_queue(struct request_queue
*q
);
807 extern void blk_start_queue_async(struct request_queue
*q
);
808 extern void blk_stop_queue(struct request_queue
*q
);
809 extern void blk_sync_queue(struct request_queue
*q
);
810 extern void __blk_stop_queue(struct request_queue
*q
);
811 extern void __blk_run_queue(struct request_queue
*q
);
812 extern void __blk_run_queue_uncond(struct request_queue
*q
);
813 extern void blk_run_queue(struct request_queue
*);
814 extern void blk_run_queue_async(struct request_queue
*q
);
815 extern int blk_rq_map_user(struct request_queue
*, struct request
*,
816 struct rq_map_data
*, void __user
*, unsigned long,
818 extern int blk_rq_unmap_user(struct bio
*);
819 extern int blk_rq_map_kern(struct request_queue
*, struct request
*, void *, unsigned int, gfp_t
);
820 extern int blk_rq_map_user_iov(struct request_queue
*, struct request
*,
821 struct rq_map_data
*, const struct iov_iter
*,
823 extern int blk_execute_rq(struct request_queue
*, struct gendisk
*,
824 struct request
*, int);
825 extern void blk_execute_rq_nowait(struct request_queue
*, struct gendisk
*,
826 struct request
*, int, rq_end_io_fn
*);
828 bool blk_poll(struct request_queue
*q
, blk_qc_t cookie
);
830 static inline struct request_queue
*bdev_get_queue(struct block_device
*bdev
)
832 return bdev
->bd_disk
->queue
; /* this is never NULL */
836 * blk_rq_pos() : the current sector
837 * blk_rq_bytes() : bytes left in the entire request
838 * blk_rq_cur_bytes() : bytes left in the current segment
839 * blk_rq_err_bytes() : bytes left till the next error boundary
840 * blk_rq_sectors() : sectors left in the entire request
841 * blk_rq_cur_sectors() : sectors left in the current segment
843 static inline sector_t
blk_rq_pos(const struct request
*rq
)
848 static inline unsigned int blk_rq_bytes(const struct request
*rq
)
850 return rq
->__data_len
;
853 static inline int blk_rq_cur_bytes(const struct request
*rq
)
855 return rq
->bio
? bio_cur_bytes(rq
->bio
) : 0;
858 extern unsigned int blk_rq_err_bytes(const struct request
*rq
);
860 static inline unsigned int blk_rq_sectors(const struct request
*rq
)
862 return blk_rq_bytes(rq
) >> 9;
865 static inline unsigned int blk_rq_cur_sectors(const struct request
*rq
)
867 return blk_rq_cur_bytes(rq
) >> 9;
870 static inline unsigned int blk_queue_get_max_sectors(struct request_queue
*q
,
871 unsigned int cmd_flags
)
873 if (unlikely(cmd_flags
& REQ_DISCARD
))
874 return min(q
->limits
.max_discard_sectors
, UINT_MAX
>> 9);
876 if (unlikely(cmd_flags
& REQ_WRITE_SAME
))
877 return q
->limits
.max_write_same_sectors
;
879 return q
->limits
.max_sectors
;
883 * Return maximum size of a request at given offset. Only valid for
884 * file system requests.
886 static inline unsigned int blk_max_size_offset(struct request_queue
*q
,
889 if (!q
->limits
.chunk_sectors
)
890 return q
->limits
.max_sectors
;
892 return q
->limits
.chunk_sectors
-
893 (offset
& (q
->limits
.chunk_sectors
- 1));
896 static inline unsigned int blk_rq_get_max_sectors(struct request
*rq
)
898 struct request_queue
*q
= rq
->q
;
900 if (unlikely(rq
->cmd_type
!= REQ_TYPE_FS
))
901 return q
->limits
.max_hw_sectors
;
903 if (!q
->limits
.chunk_sectors
|| (rq
->cmd_flags
& REQ_DISCARD
))
904 return blk_queue_get_max_sectors(q
, rq
->cmd_flags
);
906 return min(blk_max_size_offset(q
, blk_rq_pos(rq
)),
907 blk_queue_get_max_sectors(q
, rq
->cmd_flags
));
910 static inline unsigned int blk_rq_count_bios(struct request
*rq
)
912 unsigned int nr_bios
= 0;
915 __rq_for_each_bio(bio
, rq
)
922 * Request issue related functions.
924 extern struct request
*blk_peek_request(struct request_queue
*q
);
925 extern void blk_start_request(struct request
*rq
);
926 extern struct request
*blk_fetch_request(struct request_queue
*q
);
929 * Request completion related functions.
931 * blk_update_request() completes given number of bytes and updates
932 * the request without completing it.
934 * blk_end_request() and friends. __blk_end_request() must be called
935 * with the request queue spinlock acquired.
937 * Several drivers define their own end_request and call
938 * blk_end_request() for parts of the original function.
939 * This prevents code duplication in drivers.
941 extern bool blk_update_request(struct request
*rq
, int error
,
942 unsigned int nr_bytes
);
943 extern void blk_finish_request(struct request
*rq
, int error
);
944 extern bool blk_end_request(struct request
*rq
, int error
,
945 unsigned int nr_bytes
);
946 extern void blk_end_request_all(struct request
*rq
, int error
);
947 extern bool blk_end_request_cur(struct request
*rq
, int error
);
948 extern bool blk_end_request_err(struct request
*rq
, int error
);
949 extern bool __blk_end_request(struct request
*rq
, int error
,
950 unsigned int nr_bytes
);
951 extern void __blk_end_request_all(struct request
*rq
, int error
);
952 extern bool __blk_end_request_cur(struct request
*rq
, int error
);
953 extern bool __blk_end_request_err(struct request
*rq
, int error
);
955 extern void blk_complete_request(struct request
*);
956 extern void __blk_complete_request(struct request
*);
957 extern void blk_abort_request(struct request
*);
958 extern void blk_unprep_request(struct request
*);
961 * Access functions for manipulating queue properties
963 extern struct request_queue
*blk_init_queue_node(request_fn_proc
*rfn
,
964 spinlock_t
*lock
, int node_id
);
965 extern struct request_queue
*blk_init_queue(request_fn_proc
*, spinlock_t
*);
966 extern struct request_queue
*blk_init_allocated_queue(struct request_queue
*,
967 request_fn_proc
*, spinlock_t
*);
968 extern void blk_cleanup_queue(struct request_queue
*);
969 extern void blk_queue_make_request(struct request_queue
*, make_request_fn
*);
970 extern void blk_queue_bounce_limit(struct request_queue
*, u64
);
971 extern void blk_queue_max_hw_sectors(struct request_queue
*, unsigned int);
972 extern void blk_queue_chunk_sectors(struct request_queue
*, unsigned int);
973 extern void blk_queue_max_segments(struct request_queue
*, unsigned short);
974 extern void blk_queue_max_segment_size(struct request_queue
*, unsigned int);
975 extern void blk_queue_max_discard_sectors(struct request_queue
*q
,
976 unsigned int max_discard_sectors
);
977 extern void blk_queue_max_write_same_sectors(struct request_queue
*q
,
978 unsigned int max_write_same_sectors
);
979 extern void blk_queue_logical_block_size(struct request_queue
*, unsigned short);
980 extern void blk_queue_physical_block_size(struct request_queue
*, unsigned int);
981 extern void blk_queue_alignment_offset(struct request_queue
*q
,
982 unsigned int alignment
);
983 extern void blk_limits_io_min(struct queue_limits
*limits
, unsigned int min
);
984 extern void blk_queue_io_min(struct request_queue
*q
, unsigned int min
);
985 extern void blk_limits_io_opt(struct queue_limits
*limits
, unsigned int opt
);
986 extern void blk_queue_io_opt(struct request_queue
*q
, unsigned int opt
);
987 extern void blk_set_default_limits(struct queue_limits
*lim
);
988 extern void blk_set_stacking_limits(struct queue_limits
*lim
);
989 extern int blk_stack_limits(struct queue_limits
*t
, struct queue_limits
*b
,
991 extern int bdev_stack_limits(struct queue_limits
*t
, struct block_device
*bdev
,
993 extern void disk_stack_limits(struct gendisk
*disk
, struct block_device
*bdev
,
995 extern void blk_queue_stack_limits(struct request_queue
*t
, struct request_queue
*b
);
996 extern void blk_queue_dma_pad(struct request_queue
*, unsigned int);
997 extern void blk_queue_update_dma_pad(struct request_queue
*, unsigned int);
998 extern int blk_queue_dma_drain(struct request_queue
*q
,
999 dma_drain_needed_fn
*dma_drain_needed
,
1000 void *buf
, unsigned int size
);
1001 extern void blk_queue_lld_busy(struct request_queue
*q
, lld_busy_fn
*fn
);
1002 extern void blk_queue_segment_boundary(struct request_queue
*, unsigned long);
1003 extern void blk_queue_virt_boundary(struct request_queue
*, unsigned long);
1004 extern void blk_queue_prep_rq(struct request_queue
*, prep_rq_fn
*pfn
);
1005 extern void blk_queue_unprep_rq(struct request_queue
*, unprep_rq_fn
*ufn
);
1006 extern void blk_queue_dma_alignment(struct request_queue
*, int);
1007 extern void blk_queue_update_dma_alignment(struct request_queue
*, int);
1008 extern void blk_queue_softirq_done(struct request_queue
*, softirq_done_fn
*);
1009 extern void blk_queue_rq_timed_out(struct request_queue
*, rq_timed_out_fn
*);
1010 extern void blk_queue_rq_timeout(struct request_queue
*, unsigned int);
1011 extern void blk_queue_flush_queueable(struct request_queue
*q
, bool queueable
);
1012 extern void blk_queue_write_cache(struct request_queue
*q
, bool enabled
, bool fua
);
1013 extern struct backing_dev_info
*blk_get_backing_dev_info(struct block_device
*bdev
);
1015 extern int blk_rq_map_sg(struct request_queue
*, struct request
*, struct scatterlist
*);
1016 extern void blk_dump_rq_flags(struct request
*, char *);
1017 extern long nr_blockdev_pages(void);
1019 bool __must_check
blk_get_queue(struct request_queue
*);
1020 struct request_queue
*blk_alloc_queue(gfp_t
);
1021 struct request_queue
*blk_alloc_queue_node(gfp_t
, int);
1022 extern void blk_put_queue(struct request_queue
*);
1023 extern void blk_set_queue_dying(struct request_queue
*);
1026 * block layer runtime pm functions
1029 extern void blk_pm_runtime_init(struct request_queue
*q
, struct device
*dev
);
1030 extern int blk_pre_runtime_suspend(struct request_queue
*q
);
1031 extern void blk_post_runtime_suspend(struct request_queue
*q
, int err
);
1032 extern void blk_pre_runtime_resume(struct request_queue
*q
);
1033 extern void blk_post_runtime_resume(struct request_queue
*q
, int err
);
1034 extern void blk_set_runtime_active(struct request_queue
*q
);
1036 static inline void blk_pm_runtime_init(struct request_queue
*q
,
1037 struct device
*dev
) {}
1038 static inline int blk_pre_runtime_suspend(struct request_queue
*q
)
1042 static inline void blk_post_runtime_suspend(struct request_queue
*q
, int err
) {}
1043 static inline void blk_pre_runtime_resume(struct request_queue
*q
) {}
1044 static inline void blk_post_runtime_resume(struct request_queue
*q
, int err
) {}
1045 extern inline void blk_set_runtime_active(struct request_queue
*q
) {}
1049 * blk_plug permits building a queue of related requests by holding the I/O
1050 * fragments for a short period. This allows merging of sequential requests
1051 * into single larger request. As the requests are moved from a per-task list to
1052 * the device's request_queue in a batch, this results in improved scalability
1053 * as the lock contention for request_queue lock is reduced.
1055 * It is ok not to disable preemption when adding the request to the plug list
1056 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1057 * the plug list when the task sleeps by itself. For details, please see
1058 * schedule() where blk_schedule_flush_plug() is called.
1061 struct list_head list
; /* requests */
1062 struct list_head mq_list
; /* blk-mq requests */
1063 struct list_head cb_list
; /* md requires an unplug callback */
1065 #define BLK_MAX_REQUEST_COUNT 16
1068 typedef void (*blk_plug_cb_fn
)(struct blk_plug_cb
*, bool);
1069 struct blk_plug_cb
{
1070 struct list_head list
;
1071 blk_plug_cb_fn callback
;
1074 extern struct blk_plug_cb
*blk_check_plugged(blk_plug_cb_fn unplug
,
1075 void *data
, int size
);
1076 extern void blk_start_plug(struct blk_plug
*);
1077 extern void blk_finish_plug(struct blk_plug
*);
1078 extern void blk_flush_plug_list(struct blk_plug
*, bool);
1080 static inline void blk_flush_plug(struct task_struct
*tsk
)
1082 struct blk_plug
*plug
= tsk
->plug
;
1085 blk_flush_plug_list(plug
, false);
1088 static inline void blk_schedule_flush_plug(struct task_struct
*tsk
)
1090 struct blk_plug
*plug
= tsk
->plug
;
1093 blk_flush_plug_list(plug
, true);
1096 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1098 struct blk_plug
*plug
= tsk
->plug
;
1101 (!list_empty(&plug
->list
) ||
1102 !list_empty(&plug
->mq_list
) ||
1103 !list_empty(&plug
->cb_list
));
1109 extern int blk_queue_start_tag(struct request_queue
*, struct request
*);
1110 extern struct request
*blk_queue_find_tag(struct request_queue
*, int);
1111 extern void blk_queue_end_tag(struct request_queue
*, struct request
*);
1112 extern int blk_queue_init_tags(struct request_queue
*, int, struct blk_queue_tag
*, int);
1113 extern void blk_queue_free_tags(struct request_queue
*);
1114 extern int blk_queue_resize_tags(struct request_queue
*, int);
1115 extern void blk_queue_invalidate_tags(struct request_queue
*);
1116 extern struct blk_queue_tag
*blk_init_tags(int, int);
1117 extern void blk_free_tags(struct blk_queue_tag
*);
1119 static inline struct request
*blk_map_queue_find_tag(struct blk_queue_tag
*bqt
,
1122 if (unlikely(bqt
== NULL
|| tag
>= bqt
->real_max_depth
))
1124 return bqt
->tag_index
[tag
];
1127 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1129 extern int blkdev_issue_flush(struct block_device
*, gfp_t
, sector_t
*);
1130 extern int blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
1131 sector_t nr_sects
, gfp_t gfp_mask
, unsigned long flags
);
1132 extern int blkdev_issue_write_same(struct block_device
*bdev
, sector_t sector
,
1133 sector_t nr_sects
, gfp_t gfp_mask
, struct page
*page
);
1134 extern int blkdev_issue_zeroout(struct block_device
*bdev
, sector_t sector
,
1135 sector_t nr_sects
, gfp_t gfp_mask
, bool discard
);
1136 static inline int sb_issue_discard(struct super_block
*sb
, sector_t block
,
1137 sector_t nr_blocks
, gfp_t gfp_mask
, unsigned long flags
)
1139 return blkdev_issue_discard(sb
->s_bdev
, block
<< (sb
->s_blocksize_bits
- 9),
1140 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1143 static inline int sb_issue_zeroout(struct super_block
*sb
, sector_t block
,
1144 sector_t nr_blocks
, gfp_t gfp_mask
)
1146 return blkdev_issue_zeroout(sb
->s_bdev
,
1147 block
<< (sb
->s_blocksize_bits
- 9),
1148 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1152 extern int blk_verify_command(unsigned char *cmd
, fmode_t has_write_perm
);
1154 enum blk_default_limits
{
1155 BLK_MAX_SEGMENTS
= 128,
1156 BLK_SAFE_MAX_SECTORS
= 255,
1157 BLK_DEF_MAX_SECTORS
= 2560,
1158 BLK_MAX_SEGMENT_SIZE
= 65536,
1159 BLK_SEG_BOUNDARY_MASK
= 0xFFFFFFFFUL
,
1162 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1164 static inline unsigned long queue_bounce_pfn(struct request_queue
*q
)
1166 return q
->limits
.bounce_pfn
;
1169 static inline unsigned long queue_segment_boundary(struct request_queue
*q
)
1171 return q
->limits
.seg_boundary_mask
;
1174 static inline unsigned long queue_virt_boundary(struct request_queue
*q
)
1176 return q
->limits
.virt_boundary_mask
;
1179 static inline unsigned int queue_max_sectors(struct request_queue
*q
)
1181 return q
->limits
.max_sectors
;
1184 static inline unsigned int queue_max_hw_sectors(struct request_queue
*q
)
1186 return q
->limits
.max_hw_sectors
;
1189 static inline unsigned short queue_max_segments(struct request_queue
*q
)
1191 return q
->limits
.max_segments
;
1194 static inline unsigned int queue_max_segment_size(struct request_queue
*q
)
1196 return q
->limits
.max_segment_size
;
1199 static inline unsigned short queue_logical_block_size(struct request_queue
*q
)
1203 if (q
&& q
->limits
.logical_block_size
)
1204 retval
= q
->limits
.logical_block_size
;
1209 static inline unsigned short bdev_logical_block_size(struct block_device
*bdev
)
1211 return queue_logical_block_size(bdev_get_queue(bdev
));
1214 static inline unsigned int queue_physical_block_size(struct request_queue
*q
)
1216 return q
->limits
.physical_block_size
;
1219 static inline unsigned int bdev_physical_block_size(struct block_device
*bdev
)
1221 return queue_physical_block_size(bdev_get_queue(bdev
));
1224 static inline unsigned int queue_io_min(struct request_queue
*q
)
1226 return q
->limits
.io_min
;
1229 static inline int bdev_io_min(struct block_device
*bdev
)
1231 return queue_io_min(bdev_get_queue(bdev
));
1234 static inline unsigned int queue_io_opt(struct request_queue
*q
)
1236 return q
->limits
.io_opt
;
1239 static inline int bdev_io_opt(struct block_device
*bdev
)
1241 return queue_io_opt(bdev_get_queue(bdev
));
1244 static inline int queue_alignment_offset(struct request_queue
*q
)
1246 if (q
->limits
.misaligned
)
1249 return q
->limits
.alignment_offset
;
1252 static inline int queue_limit_alignment_offset(struct queue_limits
*lim
, sector_t sector
)
1254 unsigned int granularity
= max(lim
->physical_block_size
, lim
->io_min
);
1255 unsigned int alignment
= sector_div(sector
, granularity
>> 9) << 9;
1257 return (granularity
+ lim
->alignment_offset
- alignment
) % granularity
;
1260 static inline int bdev_alignment_offset(struct block_device
*bdev
)
1262 struct request_queue
*q
= bdev_get_queue(bdev
);
1264 if (q
->limits
.misaligned
)
1267 if (bdev
!= bdev
->bd_contains
)
1268 return bdev
->bd_part
->alignment_offset
;
1270 return q
->limits
.alignment_offset
;
1273 static inline int queue_discard_alignment(struct request_queue
*q
)
1275 if (q
->limits
.discard_misaligned
)
1278 return q
->limits
.discard_alignment
;
1281 static inline int queue_limit_discard_alignment(struct queue_limits
*lim
, sector_t sector
)
1283 unsigned int alignment
, granularity
, offset
;
1285 if (!lim
->max_discard_sectors
)
1288 /* Why are these in bytes, not sectors? */
1289 alignment
= lim
->discard_alignment
>> 9;
1290 granularity
= lim
->discard_granularity
>> 9;
1294 /* Offset of the partition start in 'granularity' sectors */
1295 offset
= sector_div(sector
, granularity
);
1297 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1298 offset
= (granularity
+ alignment
- offset
) % granularity
;
1300 /* Turn it back into bytes, gaah */
1304 static inline int bdev_discard_alignment(struct block_device
*bdev
)
1306 struct request_queue
*q
= bdev_get_queue(bdev
);
1308 if (bdev
!= bdev
->bd_contains
)
1309 return bdev
->bd_part
->discard_alignment
;
1311 return q
->limits
.discard_alignment
;
1314 static inline unsigned int queue_discard_zeroes_data(struct request_queue
*q
)
1316 if (q
->limits
.max_discard_sectors
&& q
->limits
.discard_zeroes_data
== 1)
1322 static inline unsigned int bdev_discard_zeroes_data(struct block_device
*bdev
)
1324 return queue_discard_zeroes_data(bdev_get_queue(bdev
));
1327 static inline unsigned int bdev_write_same(struct block_device
*bdev
)
1329 struct request_queue
*q
= bdev_get_queue(bdev
);
1332 return q
->limits
.max_write_same_sectors
;
1337 static inline int queue_dma_alignment(struct request_queue
*q
)
1339 return q
? q
->dma_alignment
: 511;
1342 static inline int blk_rq_aligned(struct request_queue
*q
, unsigned long addr
,
1345 unsigned int alignment
= queue_dma_alignment(q
) | q
->dma_pad_mask
;
1346 return !(addr
& alignment
) && !(len
& alignment
);
1349 /* assumes size > 256 */
1350 static inline unsigned int blksize_bits(unsigned int size
)
1352 unsigned int bits
= 8;
1356 } while (size
> 256);
1360 static inline unsigned int block_size(struct block_device
*bdev
)
1362 return bdev
->bd_block_size
;
1365 static inline bool queue_flush_queueable(struct request_queue
*q
)
1367 return !test_bit(QUEUE_FLAG_FLUSH_NQ
, &q
->queue_flags
);
1370 typedef struct {struct page
*v
;} Sector
;
1372 unsigned char *read_dev_sector(struct block_device
*, sector_t
, Sector
*);
1374 static inline void put_dev_sector(Sector p
)
1379 static inline bool __bvec_gap_to_prev(struct request_queue
*q
,
1380 struct bio_vec
*bprv
, unsigned int offset
)
1383 ((bprv
->bv_offset
+ bprv
->bv_len
) & queue_virt_boundary(q
));
1387 * Check if adding a bio_vec after bprv with offset would create a gap in
1388 * the SG list. Most drivers don't care about this, but some do.
1390 static inline bool bvec_gap_to_prev(struct request_queue
*q
,
1391 struct bio_vec
*bprv
, unsigned int offset
)
1393 if (!queue_virt_boundary(q
))
1395 return __bvec_gap_to_prev(q
, bprv
, offset
);
1398 static inline bool bio_will_gap(struct request_queue
*q
, struct bio
*prev
,
1401 if (bio_has_data(prev
) && queue_virt_boundary(q
)) {
1402 struct bio_vec pb
, nb
;
1404 bio_get_last_bvec(prev
, &pb
);
1405 bio_get_first_bvec(next
, &nb
);
1407 return __bvec_gap_to_prev(q
, &pb
, nb
.bv_offset
);
1413 static inline bool req_gap_back_merge(struct request
*req
, struct bio
*bio
)
1415 return bio_will_gap(req
->q
, req
->biotail
, bio
);
1418 static inline bool req_gap_front_merge(struct request
*req
, struct bio
*bio
)
1420 return bio_will_gap(req
->q
, bio
, req
->bio
);
1424 int kblockd_schedule_work(struct work_struct
*work
);
1425 int kblockd_schedule_delayed_work(struct delayed_work
*dwork
, unsigned long delay
);
1426 int kblockd_schedule_delayed_work_on(int cpu
, struct delayed_work
*dwork
, unsigned long delay
);
1428 #ifdef CONFIG_BLK_CGROUP
1430 * This should not be using sched_clock(). A real patch is in progress
1431 * to fix this up, until that is in place we need to disable preemption
1432 * around sched_clock() in this function and set_io_start_time_ns().
1434 static inline void set_start_time_ns(struct request
*req
)
1437 req
->start_time_ns
= sched_clock();
1441 static inline void set_io_start_time_ns(struct request
*req
)
1444 req
->io_start_time_ns
= sched_clock();
1448 static inline uint64_t rq_start_time_ns(struct request
*req
)
1450 return req
->start_time_ns
;
1453 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1455 return req
->io_start_time_ns
;
1458 static inline void set_start_time_ns(struct request
*req
) {}
1459 static inline void set_io_start_time_ns(struct request
*req
) {}
1460 static inline uint64_t rq_start_time_ns(struct request
*req
)
1464 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1470 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1471 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1472 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1473 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1475 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1477 enum blk_integrity_flags
{
1478 BLK_INTEGRITY_VERIFY
= 1 << 0,
1479 BLK_INTEGRITY_GENERATE
= 1 << 1,
1480 BLK_INTEGRITY_DEVICE_CAPABLE
= 1 << 2,
1481 BLK_INTEGRITY_IP_CHECKSUM
= 1 << 3,
1484 struct blk_integrity_iter
{
1488 unsigned int data_size
;
1489 unsigned short interval
;
1490 const char *disk_name
;
1493 typedef int (integrity_processing_fn
) (struct blk_integrity_iter
*);
1495 struct blk_integrity_profile
{
1496 integrity_processing_fn
*generate_fn
;
1497 integrity_processing_fn
*verify_fn
;
1501 extern void blk_integrity_register(struct gendisk
*, struct blk_integrity
*);
1502 extern void blk_integrity_unregister(struct gendisk
*);
1503 extern int blk_integrity_compare(struct gendisk
*, struct gendisk
*);
1504 extern int blk_rq_map_integrity_sg(struct request_queue
*, struct bio
*,
1505 struct scatterlist
*);
1506 extern int blk_rq_count_integrity_sg(struct request_queue
*, struct bio
*);
1507 extern bool blk_integrity_merge_rq(struct request_queue
*, struct request
*,
1509 extern bool blk_integrity_merge_bio(struct request_queue
*, struct request
*,
1512 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1514 struct blk_integrity
*bi
= &disk
->queue
->integrity
;
1523 struct blk_integrity
*bdev_get_integrity(struct block_device
*bdev
)
1525 return blk_get_integrity(bdev
->bd_disk
);
1528 static inline bool blk_integrity_rq(struct request
*rq
)
1530 return rq
->cmd_flags
& REQ_INTEGRITY
;
1533 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1536 q
->limits
.max_integrity_segments
= segs
;
1539 static inline unsigned short
1540 queue_max_integrity_segments(struct request_queue
*q
)
1542 return q
->limits
.max_integrity_segments
;
1545 static inline bool integrity_req_gap_back_merge(struct request
*req
,
1548 struct bio_integrity_payload
*bip
= bio_integrity(req
->bio
);
1549 struct bio_integrity_payload
*bip_next
= bio_integrity(next
);
1551 return bvec_gap_to_prev(req
->q
, &bip
->bip_vec
[bip
->bip_vcnt
- 1],
1552 bip_next
->bip_vec
[0].bv_offset
);
1555 static inline bool integrity_req_gap_front_merge(struct request
*req
,
1558 struct bio_integrity_payload
*bip
= bio_integrity(bio
);
1559 struct bio_integrity_payload
*bip_next
= bio_integrity(req
->bio
);
1561 return bvec_gap_to_prev(req
->q
, &bip
->bip_vec
[bip
->bip_vcnt
- 1],
1562 bip_next
->bip_vec
[0].bv_offset
);
1565 #else /* CONFIG_BLK_DEV_INTEGRITY */
1568 struct block_device
;
1570 struct blk_integrity
;
1572 static inline int blk_integrity_rq(struct request
*rq
)
1576 static inline int blk_rq_count_integrity_sg(struct request_queue
*q
,
1581 static inline int blk_rq_map_integrity_sg(struct request_queue
*q
,
1583 struct scatterlist
*s
)
1587 static inline struct blk_integrity
*bdev_get_integrity(struct block_device
*b
)
1591 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1595 static inline int blk_integrity_compare(struct gendisk
*a
, struct gendisk
*b
)
1599 static inline void blk_integrity_register(struct gendisk
*d
,
1600 struct blk_integrity
*b
)
1603 static inline void blk_integrity_unregister(struct gendisk
*d
)
1606 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1610 static inline unsigned short queue_max_integrity_segments(struct request_queue
*q
)
1614 static inline bool blk_integrity_merge_rq(struct request_queue
*rq
,
1620 static inline bool blk_integrity_merge_bio(struct request_queue
*rq
,
1627 static inline bool integrity_req_gap_back_merge(struct request
*req
,
1632 static inline bool integrity_req_gap_front_merge(struct request
*req
,
1638 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1641 * struct blk_dax_ctl - control and output parameters for ->direct_access
1642 * @sector: (input) offset relative to a block_device
1643 * @addr: (output) kernel virtual address for @sector populated by driver
1644 * @pfn: (output) page frame number for @addr populated by driver
1645 * @size: (input) number of bytes requested
1647 struct blk_dax_ctl
{
1654 struct block_device_operations
{
1655 int (*open
) (struct block_device
*, fmode_t
);
1656 void (*release
) (struct gendisk
*, fmode_t
);
1657 int (*rw_page
)(struct block_device
*, sector_t
, struct page
*, int rw
);
1658 int (*ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1659 int (*compat_ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1660 long (*direct_access
)(struct block_device
*, sector_t
, void __pmem
**,
1662 unsigned int (*check_events
) (struct gendisk
*disk
,
1663 unsigned int clearing
);
1664 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1665 int (*media_changed
) (struct gendisk
*);
1666 void (*unlock_native_capacity
) (struct gendisk
*);
1667 int (*revalidate_disk
) (struct gendisk
*);
1668 int (*getgeo
)(struct block_device
*, struct hd_geometry
*);
1669 /* this callback is with swap_lock and sometimes page table lock held */
1670 void (*swap_slot_free_notify
) (struct block_device
*, unsigned long);
1671 struct module
*owner
;
1672 const struct pr_ops
*pr_ops
;
1675 extern int __blkdev_driver_ioctl(struct block_device
*, fmode_t
, unsigned int,
1677 extern int bdev_read_page(struct block_device
*, sector_t
, struct page
*);
1678 extern int bdev_write_page(struct block_device
*, sector_t
, struct page
*,
1679 struct writeback_control
*);
1680 extern long bdev_direct_access(struct block_device
*, struct blk_dax_ctl
*);
1681 #else /* CONFIG_BLOCK */
1683 struct block_device
;
1686 * stubs for when the block layer is configured out
1688 #define buffer_heads_over_limit 0
1690 static inline long nr_blockdev_pages(void)
1698 static inline void blk_start_plug(struct blk_plug
*plug
)
1702 static inline void blk_finish_plug(struct blk_plug
*plug
)
1706 static inline void blk_flush_plug(struct task_struct
*task
)
1710 static inline void blk_schedule_flush_plug(struct task_struct
*task
)
1715 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1720 static inline int blkdev_issue_flush(struct block_device
*bdev
, gfp_t gfp_mask
,
1721 sector_t
*error_sector
)
1726 #endif /* CONFIG_BLOCK */