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.h>
16 #include <linux/wait.h>
17 #include <linux/mempool.h>
18 #include <linux/bio.h>
19 #include <linux/stringify.h>
20 #include <linux/gfp.h>
21 #include <linux/bsg.h>
22 #include <linux/smp.h>
23 #include <linux/rcupdate.h>
25 #include <asm/scatterlist.h>
28 struct scsi_ioctl_command
;
31 struct elevator_queue
;
32 struct request_pm_state
;
39 #define BLKDEV_MIN_RQ 4
40 #define BLKDEV_MAX_RQ 128 /* Default maximum */
43 * Maximum number of blkcg policies allowed to be registered concurrently.
44 * Defined here to simplify include dependency.
46 #define BLKCG_MAX_POLS 2
49 typedef void (rq_end_io_fn
)(struct request
*, int);
51 #define BLK_RL_SYNCFULL (1U << 0)
52 #define BLK_RL_ASYNCFULL (1U << 1)
55 struct request_queue
*q
; /* the queue this rl belongs to */
56 #ifdef CONFIG_BLK_CGROUP
57 struct blkcg_gq
*blkg
; /* blkg this request pool belongs to */
60 * count[], starved[], and wait[] are indexed by
61 * BLK_RW_SYNC/BLK_RW_ASYNC
66 wait_queue_head_t wait
[2];
71 * request command types
73 enum rq_cmd_type_bits
{
74 REQ_TYPE_FS
= 1, /* fs request */
75 REQ_TYPE_BLOCK_PC
, /* scsi command */
76 REQ_TYPE_SENSE
, /* sense request */
77 REQ_TYPE_PM_SUSPEND
, /* suspend request */
78 REQ_TYPE_PM_RESUME
, /* resume request */
79 REQ_TYPE_PM_SHUTDOWN
, /* shutdown request */
80 REQ_TYPE_SPECIAL
, /* driver defined type */
82 * for ATA/ATAPI devices. this really doesn't belong here, ide should
83 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
84 * private REQ_LB opcodes to differentiate what type of request this is
86 REQ_TYPE_ATA_TASKFILE
,
90 #define BLK_MAX_CDB 16
93 * Try to put the fields that are referenced together in the same cacheline.
95 * If you modify this structure, make sure to update blk_rq_init() and
96 * especially blk_mq_rq_ctx_init() to take care of the added fields.
99 struct list_head queuelist
;
101 struct call_single_data csd
;
102 unsigned long fifo_time
;
105 struct request_queue
*q
;
106 struct blk_mq_ctx
*mq_ctx
;
109 enum rq_cmd_type_bits cmd_type
;
110 unsigned long atomic_flags
;
114 /* the following two fields are internal, NEVER access directly */
115 unsigned int __data_len
; /* total data len */
116 sector_t __sector
; /* sector cursor */
122 * The hash is used inside the scheduler, and killed once the
123 * request reaches the dispatch list. The ipi_list is only used
124 * to queue the request for softirq completion, which is long
125 * after the request has been unhashed (and even removed from
126 * the dispatch list).
129 struct hlist_node hash
; /* merge hash */
130 struct list_head ipi_list
;
134 * The rb_node is only used inside the io scheduler, requests
135 * are pruned when moved to the dispatch queue. So let the
136 * completion_data share space with the rb_node.
139 struct rb_node rb_node
; /* sort/lookup */
140 void *completion_data
;
144 * Three pointers are available for the IO schedulers, if they need
145 * more they have to dynamically allocate it. Flush requests are
146 * never put on the IO scheduler. So let the flush fields share
147 * space with the elevator data.
157 struct list_head list
;
158 rq_end_io_fn
*saved_end_io
;
162 struct gendisk
*rq_disk
;
163 struct hd_struct
*part
;
164 unsigned long start_time
;
165 #ifdef CONFIG_BLK_CGROUP
166 struct request_list
*rl
; /* rl this rq is alloced from */
167 unsigned long long start_time_ns
;
168 unsigned long long io_start_time_ns
; /* when passed to hardware */
170 /* Number of scatter-gather DMA addr+len pairs after
171 * physical address coalescing is performed.
173 unsigned short nr_phys_segments
;
174 #if defined(CONFIG_BLK_DEV_INTEGRITY)
175 unsigned short nr_integrity_segments
;
178 unsigned short ioprio
;
180 void *special
; /* opaque pointer available for LLD use */
186 * when request is used as a packet command carrier
188 unsigned char __cmd
[BLK_MAX_CDB
];
190 unsigned short cmd_len
;
192 unsigned int extra_len
; /* length of alignment and padding */
193 unsigned int sense_len
;
194 unsigned int resid_len
; /* residual count */
197 unsigned long deadline
;
198 struct list_head timeout_list
;
199 unsigned int timeout
;
203 * completion callback.
205 rq_end_io_fn
*end_io
;
209 struct request
*next_rq
;
212 static inline unsigned short req_get_ioprio(struct request
*req
)
218 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
219 * requests. Some step values could eventually be made generic.
221 struct request_pm_state
223 /* PM state machine step value, currently driver specific */
225 /* requested PM state value (S1, S2, S3, S4, ...) */
227 void* data
; /* for driver use */
230 #include <linux/elevator.h>
232 struct blk_queue_ctx
;
234 typedef void (request_fn_proc
) (struct request_queue
*q
);
235 typedef void (make_request_fn
) (struct request_queue
*q
, struct bio
*bio
);
236 typedef int (prep_rq_fn
) (struct request_queue
*, struct request
*);
237 typedef void (unprep_rq_fn
) (struct request_queue
*, struct request
*);
240 struct bvec_merge_data
{
241 struct block_device
*bi_bdev
;
246 typedef int (merge_bvec_fn
) (struct request_queue
*, struct bvec_merge_data
*,
248 typedef void (softirq_done_fn
)(struct request
*);
249 typedef int (dma_drain_needed_fn
)(struct request
*);
250 typedef int (lld_busy_fn
) (struct request_queue
*q
);
251 typedef int (bsg_job_fn
) (struct bsg_job
*);
253 enum blk_eh_timer_return
{
259 typedef enum blk_eh_timer_return (rq_timed_out_fn
)(struct request
*);
261 enum blk_queue_state
{
266 struct blk_queue_tag
{
267 struct request
**tag_index
; /* map of busy tags */
268 unsigned long *tag_map
; /* bit map of free/busy tags */
269 int busy
; /* current depth */
270 int max_depth
; /* what we will send to device */
271 int real_max_depth
; /* what the array can hold */
272 atomic_t refcnt
; /* map can be shared */
275 #define BLK_SCSI_MAX_CMDS (256)
276 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
278 struct queue_limits
{
279 unsigned long bounce_pfn
;
280 unsigned long seg_boundary_mask
;
282 unsigned int max_hw_sectors
;
283 unsigned int chunk_sectors
;
284 unsigned int max_sectors
;
285 unsigned int max_segment_size
;
286 unsigned int physical_block_size
;
287 unsigned int alignment_offset
;
290 unsigned int max_discard_sectors
;
291 unsigned int max_write_same_sectors
;
292 unsigned int discard_granularity
;
293 unsigned int discard_alignment
;
295 unsigned short logical_block_size
;
296 unsigned short max_segments
;
297 unsigned short max_integrity_segments
;
299 unsigned char misaligned
;
300 unsigned char discard_misaligned
;
301 unsigned char cluster
;
302 unsigned char discard_zeroes_data
;
303 unsigned char raid_partial_stripes_expensive
;
306 struct request_queue
{
308 * Together with queue_head for cacheline sharing
310 struct list_head queue_head
;
311 struct request
*last_merge
;
312 struct elevator_queue
*elevator
;
313 int nr_rqs
[2]; /* # allocated [a]sync rqs */
314 int nr_rqs_elvpriv
; /* # allocated rqs w/ elvpriv */
317 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
318 * is used, root blkg allocates from @q->root_rl and all other
319 * blkgs from their own blkg->rl. Which one to use should be
320 * determined using bio_request_list().
322 struct request_list root_rl
;
324 request_fn_proc
*request_fn
;
325 make_request_fn
*make_request_fn
;
326 prep_rq_fn
*prep_rq_fn
;
327 unprep_rq_fn
*unprep_rq_fn
;
328 merge_bvec_fn
*merge_bvec_fn
;
329 softirq_done_fn
*softirq_done_fn
;
330 rq_timed_out_fn
*rq_timed_out_fn
;
331 dma_drain_needed_fn
*dma_drain_needed
;
332 lld_busy_fn
*lld_busy_fn
;
334 struct blk_mq_ops
*mq_ops
;
336 unsigned int *mq_map
;
339 struct blk_mq_ctx __percpu
*queue_ctx
;
340 unsigned int nr_queues
;
342 /* hw dispatch queues */
343 struct blk_mq_hw_ctx
**queue_hw_ctx
;
344 unsigned int nr_hw_queues
;
347 * Dispatch queue sorting
350 struct request
*boundary_rq
;
353 * Delayed queue handling
355 struct delayed_work delay_work
;
357 struct backing_dev_info backing_dev_info
;
360 * The queue owner gets to use this for whatever they like.
361 * ll_rw_blk doesn't touch it.
366 * various queue flags, see QUEUE_* below
368 unsigned long queue_flags
;
371 * ida allocated id for this queue. Used to index queues from
377 * queue needs bounce pages for pages above this limit
382 * protects queue structures from reentrancy. ->__queue_lock should
383 * _never_ be used directly, it is queue private. always use
386 spinlock_t __queue_lock
;
387 spinlock_t
*queue_lock
;
397 struct kobject mq_kobj
;
399 #ifdef CONFIG_PM_RUNTIME
402 unsigned int nr_pending
;
408 unsigned long nr_requests
; /* Max # of requests */
409 unsigned int nr_congestion_on
;
410 unsigned int nr_congestion_off
;
411 unsigned int nr_batching
;
413 unsigned int dma_drain_size
;
414 void *dma_drain_buffer
;
415 unsigned int dma_pad_mask
;
416 unsigned int dma_alignment
;
418 struct blk_queue_tag
*queue_tags
;
419 struct list_head tag_busy_list
;
421 unsigned int nr_sorted
;
422 unsigned int in_flight
[2];
424 * Number of active block driver functions for which blk_drain_queue()
425 * must wait. Must be incremented around functions that unlock the
426 * queue_lock internally, e.g. scsi_request_fn().
428 unsigned int request_fn_active
;
430 unsigned int rq_timeout
;
431 struct timer_list timeout
;
432 struct list_head timeout_list
;
434 struct list_head icq_list
;
435 #ifdef CONFIG_BLK_CGROUP
436 DECLARE_BITMAP (blkcg_pols
, BLKCG_MAX_POLS
);
437 struct blkcg_gq
*root_blkg
;
438 struct list_head blkg_list
;
441 struct queue_limits limits
;
446 unsigned int sg_timeout
;
447 unsigned int sg_reserved_size
;
449 #ifdef CONFIG_BLK_DEV_IO_TRACE
450 struct blk_trace
*blk_trace
;
453 * for flush operations
455 unsigned int flush_flags
;
456 unsigned int flush_not_queueable
:1;
457 unsigned int flush_queue_delayed
:1;
458 unsigned int flush_pending_idx
:1;
459 unsigned int flush_running_idx
:1;
460 unsigned long flush_pending_since
;
461 struct list_head flush_queue
[2];
462 struct list_head flush_data_in_flight
;
463 struct request
*flush_rq
;
464 spinlock_t mq_flush_lock
;
466 struct list_head requeue_list
;
467 spinlock_t requeue_lock
;
468 struct work_struct requeue_work
;
470 struct mutex sysfs_lock
;
474 #if defined(CONFIG_BLK_DEV_BSG)
475 bsg_job_fn
*bsg_job_fn
;
477 struct bsg_class_device bsg_dev
;
480 #ifdef CONFIG_BLK_DEV_THROTTLING
482 struct throtl_data
*td
;
484 struct rcu_head rcu_head
;
485 wait_queue_head_t mq_freeze_wq
;
486 struct percpu_counter mq_usage_counter
;
487 struct list_head all_q_node
;
489 struct blk_mq_tag_set
*tag_set
;
490 struct list_head tag_set_list
;
493 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
494 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
495 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
496 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
497 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
498 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
499 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
500 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
501 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
502 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
503 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
504 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
505 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
506 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
507 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
508 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
509 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
510 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
511 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
512 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
513 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
514 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
515 #define QUEUE_FLAG_SG_GAPS 22 /* queue doesn't support SG gaps */
517 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
518 (1 << QUEUE_FLAG_STACKABLE) | \
519 (1 << QUEUE_FLAG_SAME_COMP) | \
520 (1 << QUEUE_FLAG_ADD_RANDOM))
522 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
523 (1 << QUEUE_FLAG_SAME_COMP))
525 static inline void queue_lockdep_assert_held(struct request_queue
*q
)
528 lockdep_assert_held(q
->queue_lock
);
531 static inline void queue_flag_set_unlocked(unsigned int flag
,
532 struct request_queue
*q
)
534 __set_bit(flag
, &q
->queue_flags
);
537 static inline int queue_flag_test_and_clear(unsigned int flag
,
538 struct request_queue
*q
)
540 queue_lockdep_assert_held(q
);
542 if (test_bit(flag
, &q
->queue_flags
)) {
543 __clear_bit(flag
, &q
->queue_flags
);
550 static inline int queue_flag_test_and_set(unsigned int flag
,
551 struct request_queue
*q
)
553 queue_lockdep_assert_held(q
);
555 if (!test_bit(flag
, &q
->queue_flags
)) {
556 __set_bit(flag
, &q
->queue_flags
);
563 static inline void queue_flag_set(unsigned int flag
, struct request_queue
*q
)
565 queue_lockdep_assert_held(q
);
566 __set_bit(flag
, &q
->queue_flags
);
569 static inline void queue_flag_clear_unlocked(unsigned int flag
,
570 struct request_queue
*q
)
572 __clear_bit(flag
, &q
->queue_flags
);
575 static inline int queue_in_flight(struct request_queue
*q
)
577 return q
->in_flight
[0] + q
->in_flight
[1];
580 static inline void queue_flag_clear(unsigned int flag
, struct request_queue
*q
)
582 queue_lockdep_assert_held(q
);
583 __clear_bit(flag
, &q
->queue_flags
);
586 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
587 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
588 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
589 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
590 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
591 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
592 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
593 #define blk_queue_noxmerges(q) \
594 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
595 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
596 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
597 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
598 #define blk_queue_stackable(q) \
599 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
600 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
601 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
602 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
604 #define blk_noretry_request(rq) \
605 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
606 REQ_FAILFAST_DRIVER))
608 #define blk_account_rq(rq) \
609 (((rq)->cmd_flags & REQ_STARTED) && \
610 ((rq)->cmd_type == REQ_TYPE_FS))
612 #define blk_pm_request(rq) \
613 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
614 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
616 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
617 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
618 /* rq->queuelist of dequeued request must be list_empty() */
619 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
621 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
623 #define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
626 * Driver can handle struct request, if it either has an old style
627 * request_fn defined, or is blk-mq based.
629 static inline bool queue_is_rq_based(struct request_queue
*q
)
631 return q
->request_fn
|| q
->mq_ops
;
634 static inline unsigned int blk_queue_cluster(struct request_queue
*q
)
636 return q
->limits
.cluster
;
640 * We regard a request as sync, if either a read or a sync write
642 static inline bool rw_is_sync(unsigned int rw_flags
)
644 return !(rw_flags
& REQ_WRITE
) || (rw_flags
& REQ_SYNC
);
647 static inline bool rq_is_sync(struct request
*rq
)
649 return rw_is_sync(rq
->cmd_flags
);
652 static inline bool blk_rl_full(struct request_list
*rl
, bool sync
)
654 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
656 return rl
->flags
& flag
;
659 static inline void blk_set_rl_full(struct request_list
*rl
, bool sync
)
661 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
666 static inline void blk_clear_rl_full(struct request_list
*rl
, bool sync
)
668 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
673 static inline bool rq_mergeable(struct request
*rq
)
675 if (rq
->cmd_type
!= REQ_TYPE_FS
)
678 if (rq
->cmd_flags
& REQ_NOMERGE_FLAGS
)
684 static inline bool blk_check_merge_flags(unsigned int flags1
,
687 if ((flags1
& REQ_DISCARD
) != (flags2
& REQ_DISCARD
))
690 if ((flags1
& REQ_SECURE
) != (flags2
& REQ_SECURE
))
693 if ((flags1
& REQ_WRITE_SAME
) != (flags2
& REQ_WRITE_SAME
))
699 static inline bool blk_write_same_mergeable(struct bio
*a
, struct bio
*b
)
701 if (bio_data(a
) == bio_data(b
))
708 * q->prep_rq_fn return values
710 #define BLKPREP_OK 0 /* serve it */
711 #define BLKPREP_KILL 1 /* fatal error, kill */
712 #define BLKPREP_DEFER 2 /* leave on queue */
714 extern unsigned long blk_max_low_pfn
, blk_max_pfn
;
717 * standard bounce addresses:
719 * BLK_BOUNCE_HIGH : bounce all highmem pages
720 * BLK_BOUNCE_ANY : don't bounce anything
721 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
724 #if BITS_PER_LONG == 32
725 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
727 #define BLK_BOUNCE_HIGH -1ULL
729 #define BLK_BOUNCE_ANY (-1ULL)
730 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
733 * default timeout for SG_IO if none specified
735 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
736 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
739 extern int init_emergency_isa_pool(void);
740 extern void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
);
742 static inline int init_emergency_isa_pool(void)
746 static inline void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
)
749 #endif /* CONFIG_MMU */
755 unsigned long offset
;
760 struct req_iterator
{
761 struct bvec_iter iter
;
765 /* This should not be used directly - use rq_for_each_segment */
766 #define for_each_bio(_bio) \
767 for (; _bio; _bio = _bio->bi_next)
768 #define __rq_for_each_bio(_bio, rq) \
770 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
772 #define rq_for_each_segment(bvl, _rq, _iter) \
773 __rq_for_each_bio(_iter.bio, _rq) \
774 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
776 #define rq_iter_last(bvec, _iter) \
777 (_iter.bio->bi_next == NULL && \
778 bio_iter_last(bvec, _iter.iter))
780 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
781 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
783 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
784 extern void rq_flush_dcache_pages(struct request
*rq
);
786 static inline void rq_flush_dcache_pages(struct request
*rq
)
791 extern int blk_register_queue(struct gendisk
*disk
);
792 extern void blk_unregister_queue(struct gendisk
*disk
);
793 extern void generic_make_request(struct bio
*bio
);
794 extern void blk_rq_init(struct request_queue
*q
, struct request
*rq
);
795 extern void blk_put_request(struct request
*);
796 extern void __blk_put_request(struct request_queue
*, struct request
*);
797 extern struct request
*blk_get_request(struct request_queue
*, int, gfp_t
);
798 extern struct request
*blk_make_request(struct request_queue
*, struct bio
*,
800 extern void blk_rq_set_block_pc(struct request
*);
801 extern void blk_requeue_request(struct request_queue
*, struct request
*);
802 extern void blk_add_request_payload(struct request
*rq
, struct page
*page
,
804 extern int blk_rq_check_limits(struct request_queue
*q
, struct request
*rq
);
805 extern int blk_lld_busy(struct request_queue
*q
);
806 extern int blk_rq_prep_clone(struct request
*rq
, struct request
*rq_src
,
807 struct bio_set
*bs
, gfp_t gfp_mask
,
808 int (*bio_ctr
)(struct bio
*, struct bio
*, void *),
810 extern void blk_rq_unprep_clone(struct request
*rq
);
811 extern int blk_insert_cloned_request(struct request_queue
*q
,
813 extern void blk_delay_queue(struct request_queue
*, unsigned long);
814 extern void blk_recount_segments(struct request_queue
*, struct bio
*);
815 extern int scsi_verify_blk_ioctl(struct block_device
*, unsigned int);
816 extern int scsi_cmd_blk_ioctl(struct block_device
*, fmode_t
,
817 unsigned int, void __user
*);
818 extern int scsi_cmd_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
819 unsigned int, void __user
*);
820 extern int sg_scsi_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
821 struct scsi_ioctl_command __user
*);
823 extern void blk_queue_bio(struct request_queue
*q
, struct bio
*bio
);
826 * A queue has just exitted congestion. Note this in the global counter of
827 * congested queues, and wake up anyone who was waiting for requests to be
830 static inline void blk_clear_queue_congested(struct request_queue
*q
, int sync
)
832 clear_bdi_congested(&q
->backing_dev_info
, sync
);
836 * A queue has just entered congestion. Flag that in the queue's VM-visible
837 * state flags and increment the global gounter of congested queues.
839 static inline void blk_set_queue_congested(struct request_queue
*q
, int sync
)
841 set_bdi_congested(&q
->backing_dev_info
, sync
);
844 extern void blk_start_queue(struct request_queue
*q
);
845 extern void blk_stop_queue(struct request_queue
*q
);
846 extern void blk_sync_queue(struct request_queue
*q
);
847 extern void __blk_stop_queue(struct request_queue
*q
);
848 extern void __blk_run_queue(struct request_queue
*q
);
849 extern void blk_run_queue(struct request_queue
*);
850 extern void blk_run_queue_async(struct request_queue
*q
);
851 extern int blk_rq_map_user(struct request_queue
*, struct request
*,
852 struct rq_map_data
*, void __user
*, unsigned long,
854 extern int blk_rq_unmap_user(struct bio
*);
855 extern int blk_rq_map_kern(struct request_queue
*, struct request
*, void *, unsigned int, gfp_t
);
856 extern int blk_rq_map_user_iov(struct request_queue
*, struct request
*,
857 struct rq_map_data
*, const struct sg_iovec
*,
858 int, unsigned int, gfp_t
);
859 extern int blk_execute_rq(struct request_queue
*, struct gendisk
*,
860 struct request
*, int);
861 extern void blk_execute_rq_nowait(struct request_queue
*, struct gendisk
*,
862 struct request
*, int, rq_end_io_fn
*);
864 static inline struct request_queue
*bdev_get_queue(struct block_device
*bdev
)
866 return bdev
->bd_disk
->queue
;
870 * blk_rq_pos() : the current sector
871 * blk_rq_bytes() : bytes left in the entire request
872 * blk_rq_cur_bytes() : bytes left in the current segment
873 * blk_rq_err_bytes() : bytes left till the next error boundary
874 * blk_rq_sectors() : sectors left in the entire request
875 * blk_rq_cur_sectors() : sectors left in the current segment
877 static inline sector_t
blk_rq_pos(const struct request
*rq
)
882 static inline unsigned int blk_rq_bytes(const struct request
*rq
)
884 return rq
->__data_len
;
887 static inline int blk_rq_cur_bytes(const struct request
*rq
)
889 return rq
->bio
? bio_cur_bytes(rq
->bio
) : 0;
892 extern unsigned int blk_rq_err_bytes(const struct request
*rq
);
894 static inline unsigned int blk_rq_sectors(const struct request
*rq
)
896 return blk_rq_bytes(rq
) >> 9;
899 static inline unsigned int blk_rq_cur_sectors(const struct request
*rq
)
901 return blk_rq_cur_bytes(rq
) >> 9;
904 static inline unsigned int blk_queue_get_max_sectors(struct request_queue
*q
,
905 unsigned int cmd_flags
)
907 if (unlikely(cmd_flags
& REQ_DISCARD
))
908 return min(q
->limits
.max_discard_sectors
, UINT_MAX
>> 9);
910 if (unlikely(cmd_flags
& REQ_WRITE_SAME
))
911 return q
->limits
.max_write_same_sectors
;
913 return q
->limits
.max_sectors
;
917 * Return maximum size of a request at given offset. Only valid for
918 * file system requests.
920 static inline unsigned int blk_max_size_offset(struct request_queue
*q
,
923 if (!q
->limits
.chunk_sectors
)
924 return q
->limits
.max_sectors
;
926 return q
->limits
.chunk_sectors
-
927 (offset
& (q
->limits
.chunk_sectors
- 1));
930 static inline unsigned int blk_rq_get_max_sectors(struct request
*rq
)
932 struct request_queue
*q
= rq
->q
;
934 if (unlikely(rq
->cmd_type
== REQ_TYPE_BLOCK_PC
))
935 return q
->limits
.max_hw_sectors
;
937 if (!q
->limits
.chunk_sectors
)
938 return blk_queue_get_max_sectors(q
, rq
->cmd_flags
);
940 return min(blk_max_size_offset(q
, blk_rq_pos(rq
)),
941 blk_queue_get_max_sectors(q
, rq
->cmd_flags
));
944 static inline unsigned int blk_rq_count_bios(struct request
*rq
)
946 unsigned int nr_bios
= 0;
949 __rq_for_each_bio(bio
, rq
)
956 * Request issue related functions.
958 extern struct request
*blk_peek_request(struct request_queue
*q
);
959 extern void blk_start_request(struct request
*rq
);
960 extern struct request
*blk_fetch_request(struct request_queue
*q
);
963 * Request completion related functions.
965 * blk_update_request() completes given number of bytes and updates
966 * the request without completing it.
968 * blk_end_request() and friends. __blk_end_request() must be called
969 * with the request queue spinlock acquired.
971 * Several drivers define their own end_request and call
972 * blk_end_request() for parts of the original function.
973 * This prevents code duplication in drivers.
975 extern bool blk_update_request(struct request
*rq
, int error
,
976 unsigned int nr_bytes
);
977 extern void blk_finish_request(struct request
*rq
, int error
);
978 extern bool blk_end_request(struct request
*rq
, int error
,
979 unsigned int nr_bytes
);
980 extern void blk_end_request_all(struct request
*rq
, int error
);
981 extern bool blk_end_request_cur(struct request
*rq
, int error
);
982 extern bool blk_end_request_err(struct request
*rq
, int error
);
983 extern bool __blk_end_request(struct request
*rq
, int error
,
984 unsigned int nr_bytes
);
985 extern void __blk_end_request_all(struct request
*rq
, int error
);
986 extern bool __blk_end_request_cur(struct request
*rq
, int error
);
987 extern bool __blk_end_request_err(struct request
*rq
, int error
);
989 extern void blk_complete_request(struct request
*);
990 extern void __blk_complete_request(struct request
*);
991 extern void blk_abort_request(struct request
*);
992 extern void blk_unprep_request(struct request
*);
995 * Access functions for manipulating queue properties
997 extern struct request_queue
*blk_init_queue_node(request_fn_proc
*rfn
,
998 spinlock_t
*lock
, int node_id
);
999 extern struct request_queue
*blk_init_queue(request_fn_proc
*, spinlock_t
*);
1000 extern struct request_queue
*blk_init_allocated_queue(struct request_queue
*,
1001 request_fn_proc
*, spinlock_t
*);
1002 extern void blk_cleanup_queue(struct request_queue
*);
1003 extern void blk_queue_make_request(struct request_queue
*, make_request_fn
*);
1004 extern void blk_queue_bounce_limit(struct request_queue
*, u64
);
1005 extern void blk_limits_max_hw_sectors(struct queue_limits
*, unsigned int);
1006 extern void blk_queue_max_hw_sectors(struct request_queue
*, unsigned int);
1007 extern void blk_queue_chunk_sectors(struct request_queue
*, unsigned int);
1008 extern void blk_queue_max_segments(struct request_queue
*, unsigned short);
1009 extern void blk_queue_max_segment_size(struct request_queue
*, unsigned int);
1010 extern void blk_queue_max_discard_sectors(struct request_queue
*q
,
1011 unsigned int max_discard_sectors
);
1012 extern void blk_queue_max_write_same_sectors(struct request_queue
*q
,
1013 unsigned int max_write_same_sectors
);
1014 extern void blk_queue_logical_block_size(struct request_queue
*, unsigned short);
1015 extern void blk_queue_physical_block_size(struct request_queue
*, unsigned int);
1016 extern void blk_queue_alignment_offset(struct request_queue
*q
,
1017 unsigned int alignment
);
1018 extern void blk_limits_io_min(struct queue_limits
*limits
, unsigned int min
);
1019 extern void blk_queue_io_min(struct request_queue
*q
, unsigned int min
);
1020 extern void blk_limits_io_opt(struct queue_limits
*limits
, unsigned int opt
);
1021 extern void blk_queue_io_opt(struct request_queue
*q
, unsigned int opt
);
1022 extern void blk_set_default_limits(struct queue_limits
*lim
);
1023 extern void blk_set_stacking_limits(struct queue_limits
*lim
);
1024 extern int blk_stack_limits(struct queue_limits
*t
, struct queue_limits
*b
,
1026 extern int bdev_stack_limits(struct queue_limits
*t
, struct block_device
*bdev
,
1028 extern void disk_stack_limits(struct gendisk
*disk
, struct block_device
*bdev
,
1030 extern void blk_queue_stack_limits(struct request_queue
*t
, struct request_queue
*b
);
1031 extern void blk_queue_dma_pad(struct request_queue
*, unsigned int);
1032 extern void blk_queue_update_dma_pad(struct request_queue
*, unsigned int);
1033 extern int blk_queue_dma_drain(struct request_queue
*q
,
1034 dma_drain_needed_fn
*dma_drain_needed
,
1035 void *buf
, unsigned int size
);
1036 extern void blk_queue_lld_busy(struct request_queue
*q
, lld_busy_fn
*fn
);
1037 extern void blk_queue_segment_boundary(struct request_queue
*, unsigned long);
1038 extern void blk_queue_prep_rq(struct request_queue
*, prep_rq_fn
*pfn
);
1039 extern void blk_queue_unprep_rq(struct request_queue
*, unprep_rq_fn
*ufn
);
1040 extern void blk_queue_merge_bvec(struct request_queue
*, merge_bvec_fn
*);
1041 extern void blk_queue_dma_alignment(struct request_queue
*, int);
1042 extern void blk_queue_update_dma_alignment(struct request_queue
*, int);
1043 extern void blk_queue_softirq_done(struct request_queue
*, softirq_done_fn
*);
1044 extern void blk_queue_rq_timed_out(struct request_queue
*, rq_timed_out_fn
*);
1045 extern void blk_queue_rq_timeout(struct request_queue
*, unsigned int);
1046 extern void blk_queue_flush(struct request_queue
*q
, unsigned int flush
);
1047 extern void blk_queue_flush_queueable(struct request_queue
*q
, bool queueable
);
1048 extern struct backing_dev_info
*blk_get_backing_dev_info(struct block_device
*bdev
);
1050 extern int blk_rq_map_sg(struct request_queue
*, struct request
*, struct scatterlist
*);
1051 extern int blk_bio_map_sg(struct request_queue
*q
, struct bio
*bio
,
1052 struct scatterlist
*sglist
);
1053 extern void blk_dump_rq_flags(struct request
*, char *);
1054 extern long nr_blockdev_pages(void);
1056 bool __must_check
blk_get_queue(struct request_queue
*);
1057 struct request_queue
*blk_alloc_queue(gfp_t
);
1058 struct request_queue
*blk_alloc_queue_node(gfp_t
, int);
1059 extern void blk_put_queue(struct request_queue
*);
1062 * block layer runtime pm functions
1064 #ifdef CONFIG_PM_RUNTIME
1065 extern void blk_pm_runtime_init(struct request_queue
*q
, struct device
*dev
);
1066 extern int blk_pre_runtime_suspend(struct request_queue
*q
);
1067 extern void blk_post_runtime_suspend(struct request_queue
*q
, int err
);
1068 extern void blk_pre_runtime_resume(struct request_queue
*q
);
1069 extern void blk_post_runtime_resume(struct request_queue
*q
, int err
);
1071 static inline void blk_pm_runtime_init(struct request_queue
*q
,
1072 struct device
*dev
) {}
1073 static inline int blk_pre_runtime_suspend(struct request_queue
*q
)
1077 static inline void blk_post_runtime_suspend(struct request_queue
*q
, int err
) {}
1078 static inline void blk_pre_runtime_resume(struct request_queue
*q
) {}
1079 static inline void blk_post_runtime_resume(struct request_queue
*q
, int err
) {}
1083 * blk_plug permits building a queue of related requests by holding the I/O
1084 * fragments for a short period. This allows merging of sequential requests
1085 * into single larger request. As the requests are moved from a per-task list to
1086 * the device's request_queue in a batch, this results in improved scalability
1087 * as the lock contention for request_queue lock is reduced.
1089 * It is ok not to disable preemption when adding the request to the plug list
1090 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1091 * the plug list when the task sleeps by itself. For details, please see
1092 * schedule() where blk_schedule_flush_plug() is called.
1095 struct list_head list
; /* requests */
1096 struct list_head mq_list
; /* blk-mq requests */
1097 struct list_head cb_list
; /* md requires an unplug callback */
1099 #define BLK_MAX_REQUEST_COUNT 16
1102 typedef void (*blk_plug_cb_fn
)(struct blk_plug_cb
*, bool);
1103 struct blk_plug_cb
{
1104 struct list_head list
;
1105 blk_plug_cb_fn callback
;
1108 extern struct blk_plug_cb
*blk_check_plugged(blk_plug_cb_fn unplug
,
1109 void *data
, int size
);
1110 extern void blk_start_plug(struct blk_plug
*);
1111 extern void blk_finish_plug(struct blk_plug
*);
1112 extern void blk_flush_plug_list(struct blk_plug
*, bool);
1114 static inline void blk_flush_plug(struct task_struct
*tsk
)
1116 struct blk_plug
*plug
= tsk
->plug
;
1119 blk_flush_plug_list(plug
, false);
1122 static inline void blk_schedule_flush_plug(struct task_struct
*tsk
)
1124 struct blk_plug
*plug
= tsk
->plug
;
1127 blk_flush_plug_list(plug
, true);
1130 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1132 struct blk_plug
*plug
= tsk
->plug
;
1135 (!list_empty(&plug
->list
) ||
1136 !list_empty(&plug
->mq_list
) ||
1137 !list_empty(&plug
->cb_list
));
1143 #define blk_rq_tagged(rq) \
1144 ((rq)->mq_ctx || ((rq)->cmd_flags & REQ_QUEUED))
1145 extern int blk_queue_start_tag(struct request_queue
*, struct request
*);
1146 extern struct request
*blk_queue_find_tag(struct request_queue
*, int);
1147 extern void blk_queue_end_tag(struct request_queue
*, struct request
*);
1148 extern int blk_queue_init_tags(struct request_queue
*, int, struct blk_queue_tag
*);
1149 extern void blk_queue_free_tags(struct request_queue
*);
1150 extern int blk_queue_resize_tags(struct request_queue
*, int);
1151 extern void blk_queue_invalidate_tags(struct request_queue
*);
1152 extern struct blk_queue_tag
*blk_init_tags(int);
1153 extern void blk_free_tags(struct blk_queue_tag
*);
1155 static inline struct request
*blk_map_queue_find_tag(struct blk_queue_tag
*bqt
,
1158 if (unlikely(bqt
== NULL
|| tag
>= bqt
->real_max_depth
))
1160 return bqt
->tag_index
[tag
];
1163 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1165 extern int blkdev_issue_flush(struct block_device
*, gfp_t
, sector_t
*);
1166 extern int blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
1167 sector_t nr_sects
, gfp_t gfp_mask
, unsigned long flags
);
1168 extern int blkdev_issue_write_same(struct block_device
*bdev
, sector_t sector
,
1169 sector_t nr_sects
, gfp_t gfp_mask
, struct page
*page
);
1170 extern int blkdev_issue_zeroout(struct block_device
*bdev
, sector_t sector
,
1171 sector_t nr_sects
, gfp_t gfp_mask
);
1172 static inline int sb_issue_discard(struct super_block
*sb
, sector_t block
,
1173 sector_t nr_blocks
, gfp_t gfp_mask
, unsigned long flags
)
1175 return blkdev_issue_discard(sb
->s_bdev
, block
<< (sb
->s_blocksize_bits
- 9),
1176 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1179 static inline int sb_issue_zeroout(struct super_block
*sb
, sector_t block
,
1180 sector_t nr_blocks
, gfp_t gfp_mask
)
1182 return blkdev_issue_zeroout(sb
->s_bdev
,
1183 block
<< (sb
->s_blocksize_bits
- 9),
1184 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1188 extern int blk_verify_command(unsigned char *cmd
, fmode_t has_write_perm
);
1190 enum blk_default_limits
{
1191 BLK_MAX_SEGMENTS
= 128,
1192 BLK_SAFE_MAX_SECTORS
= 255,
1193 BLK_DEF_MAX_SECTORS
= 1024,
1194 BLK_MAX_SEGMENT_SIZE
= 65536,
1195 BLK_SEG_BOUNDARY_MASK
= 0xFFFFFFFFUL
,
1198 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1200 static inline unsigned long queue_bounce_pfn(struct request_queue
*q
)
1202 return q
->limits
.bounce_pfn
;
1205 static inline unsigned long queue_segment_boundary(struct request_queue
*q
)
1207 return q
->limits
.seg_boundary_mask
;
1210 static inline unsigned int queue_max_sectors(struct request_queue
*q
)
1212 return q
->limits
.max_sectors
;
1215 static inline unsigned int queue_max_hw_sectors(struct request_queue
*q
)
1217 return q
->limits
.max_hw_sectors
;
1220 static inline unsigned short queue_max_segments(struct request_queue
*q
)
1222 return q
->limits
.max_segments
;
1225 static inline unsigned int queue_max_segment_size(struct request_queue
*q
)
1227 return q
->limits
.max_segment_size
;
1230 static inline unsigned short queue_logical_block_size(struct request_queue
*q
)
1234 if (q
&& q
->limits
.logical_block_size
)
1235 retval
= q
->limits
.logical_block_size
;
1240 static inline unsigned short bdev_logical_block_size(struct block_device
*bdev
)
1242 return queue_logical_block_size(bdev_get_queue(bdev
));
1245 static inline unsigned int queue_physical_block_size(struct request_queue
*q
)
1247 return q
->limits
.physical_block_size
;
1250 static inline unsigned int bdev_physical_block_size(struct block_device
*bdev
)
1252 return queue_physical_block_size(bdev_get_queue(bdev
));
1255 static inline unsigned int queue_io_min(struct request_queue
*q
)
1257 return q
->limits
.io_min
;
1260 static inline int bdev_io_min(struct block_device
*bdev
)
1262 return queue_io_min(bdev_get_queue(bdev
));
1265 static inline unsigned int queue_io_opt(struct request_queue
*q
)
1267 return q
->limits
.io_opt
;
1270 static inline int bdev_io_opt(struct block_device
*bdev
)
1272 return queue_io_opt(bdev_get_queue(bdev
));
1275 static inline int queue_alignment_offset(struct request_queue
*q
)
1277 if (q
->limits
.misaligned
)
1280 return q
->limits
.alignment_offset
;
1283 static inline int queue_limit_alignment_offset(struct queue_limits
*lim
, sector_t sector
)
1285 unsigned int granularity
= max(lim
->physical_block_size
, lim
->io_min
);
1286 unsigned int alignment
= (sector
<< 9) & (granularity
- 1);
1288 return (granularity
+ lim
->alignment_offset
- alignment
)
1289 & (granularity
- 1);
1292 static inline int bdev_alignment_offset(struct block_device
*bdev
)
1294 struct request_queue
*q
= bdev_get_queue(bdev
);
1296 if (q
->limits
.misaligned
)
1299 if (bdev
!= bdev
->bd_contains
)
1300 return bdev
->bd_part
->alignment_offset
;
1302 return q
->limits
.alignment_offset
;
1305 static inline int queue_discard_alignment(struct request_queue
*q
)
1307 if (q
->limits
.discard_misaligned
)
1310 return q
->limits
.discard_alignment
;
1313 static inline int queue_limit_discard_alignment(struct queue_limits
*lim
, sector_t sector
)
1315 unsigned int alignment
, granularity
, offset
;
1317 if (!lim
->max_discard_sectors
)
1320 /* Why are these in bytes, not sectors? */
1321 alignment
= lim
->discard_alignment
>> 9;
1322 granularity
= lim
->discard_granularity
>> 9;
1326 /* Offset of the partition start in 'granularity' sectors */
1327 offset
= sector_div(sector
, granularity
);
1329 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1330 offset
= (granularity
+ alignment
- offset
) % granularity
;
1332 /* Turn it back into bytes, gaah */
1336 static inline int bdev_discard_alignment(struct block_device
*bdev
)
1338 struct request_queue
*q
= bdev_get_queue(bdev
);
1340 if (bdev
!= bdev
->bd_contains
)
1341 return bdev
->bd_part
->discard_alignment
;
1343 return q
->limits
.discard_alignment
;
1346 static inline unsigned int queue_discard_zeroes_data(struct request_queue
*q
)
1348 if (q
->limits
.max_discard_sectors
&& q
->limits
.discard_zeroes_data
== 1)
1354 static inline unsigned int bdev_discard_zeroes_data(struct block_device
*bdev
)
1356 return queue_discard_zeroes_data(bdev_get_queue(bdev
));
1359 static inline unsigned int bdev_write_same(struct block_device
*bdev
)
1361 struct request_queue
*q
= bdev_get_queue(bdev
);
1364 return q
->limits
.max_write_same_sectors
;
1369 static inline int queue_dma_alignment(struct request_queue
*q
)
1371 return q
? q
->dma_alignment
: 511;
1374 static inline int blk_rq_aligned(struct request_queue
*q
, unsigned long addr
,
1377 unsigned int alignment
= queue_dma_alignment(q
) | q
->dma_pad_mask
;
1378 return !(addr
& alignment
) && !(len
& alignment
);
1381 /* assumes size > 256 */
1382 static inline unsigned int blksize_bits(unsigned int size
)
1384 unsigned int bits
= 8;
1388 } while (size
> 256);
1392 static inline unsigned int block_size(struct block_device
*bdev
)
1394 return bdev
->bd_block_size
;
1397 static inline bool queue_flush_queueable(struct request_queue
*q
)
1399 return !q
->flush_not_queueable
;
1402 typedef struct {struct page
*v
;} Sector
;
1404 unsigned char *read_dev_sector(struct block_device
*, sector_t
, Sector
*);
1406 static inline void put_dev_sector(Sector p
)
1408 page_cache_release(p
.v
);
1412 int kblockd_schedule_work(struct work_struct
*work
);
1413 int kblockd_schedule_delayed_work(struct delayed_work
*dwork
, unsigned long delay
);
1414 int kblockd_schedule_delayed_work_on(int cpu
, struct delayed_work
*dwork
, unsigned long delay
);
1416 #ifdef CONFIG_BLK_CGROUP
1418 * This should not be using sched_clock(). A real patch is in progress
1419 * to fix this up, until that is in place we need to disable preemption
1420 * around sched_clock() in this function and set_io_start_time_ns().
1422 static inline void set_start_time_ns(struct request
*req
)
1425 req
->start_time_ns
= sched_clock();
1429 static inline void set_io_start_time_ns(struct request
*req
)
1432 req
->io_start_time_ns
= sched_clock();
1436 static inline uint64_t rq_start_time_ns(struct request
*req
)
1438 return req
->start_time_ns
;
1441 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1443 return req
->io_start_time_ns
;
1446 static inline void set_start_time_ns(struct request
*req
) {}
1447 static inline void set_io_start_time_ns(struct request
*req
) {}
1448 static inline uint64_t rq_start_time_ns(struct request
*req
)
1452 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1458 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1459 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1460 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1461 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1463 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1465 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */
1466 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */
1468 struct blk_integrity_exchg
{
1472 unsigned int data_size
;
1473 unsigned short sector_size
;
1474 const char *disk_name
;
1477 typedef void (integrity_gen_fn
) (struct blk_integrity_exchg
*);
1478 typedef int (integrity_vrfy_fn
) (struct blk_integrity_exchg
*);
1479 typedef void (integrity_set_tag_fn
) (void *, void *, unsigned int);
1480 typedef void (integrity_get_tag_fn
) (void *, void *, unsigned int);
1482 struct blk_integrity
{
1483 integrity_gen_fn
*generate_fn
;
1484 integrity_vrfy_fn
*verify_fn
;
1485 integrity_set_tag_fn
*set_tag_fn
;
1486 integrity_get_tag_fn
*get_tag_fn
;
1488 unsigned short flags
;
1489 unsigned short tuple_size
;
1490 unsigned short sector_size
;
1491 unsigned short tag_size
;
1495 struct kobject kobj
;
1498 extern bool blk_integrity_is_initialized(struct gendisk
*);
1499 extern int blk_integrity_register(struct gendisk
*, struct blk_integrity
*);
1500 extern void blk_integrity_unregister(struct gendisk
*);
1501 extern int blk_integrity_compare(struct gendisk
*, struct gendisk
*);
1502 extern int blk_rq_map_integrity_sg(struct request_queue
*, struct bio
*,
1503 struct scatterlist
*);
1504 extern int blk_rq_count_integrity_sg(struct request_queue
*, struct bio
*);
1505 extern int blk_integrity_merge_rq(struct request_queue
*, struct request
*,
1507 extern int blk_integrity_merge_bio(struct request_queue
*, struct request
*,
1511 struct blk_integrity
*bdev_get_integrity(struct block_device
*bdev
)
1513 return bdev
->bd_disk
->integrity
;
1516 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1518 return disk
->integrity
;
1521 static inline int blk_integrity_rq(struct request
*rq
)
1523 if (rq
->bio
== NULL
)
1526 return bio_integrity(rq
->bio
);
1529 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1532 q
->limits
.max_integrity_segments
= segs
;
1535 static inline unsigned short
1536 queue_max_integrity_segments(struct request_queue
*q
)
1538 return q
->limits
.max_integrity_segments
;
1541 #else /* CONFIG_BLK_DEV_INTEGRITY */
1544 struct block_device
;
1546 struct blk_integrity
;
1548 static inline int blk_integrity_rq(struct request
*rq
)
1552 static inline int blk_rq_count_integrity_sg(struct request_queue
*q
,
1557 static inline int blk_rq_map_integrity_sg(struct request_queue
*q
,
1559 struct scatterlist
*s
)
1563 static inline struct blk_integrity
*bdev_get_integrity(struct block_device
*b
)
1567 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1571 static inline int blk_integrity_compare(struct gendisk
*a
, struct gendisk
*b
)
1575 static inline int blk_integrity_register(struct gendisk
*d
,
1576 struct blk_integrity
*b
)
1580 static inline void blk_integrity_unregister(struct gendisk
*d
)
1583 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1587 static inline unsigned short queue_max_integrity_segments(struct request_queue
*q
)
1591 static inline int blk_integrity_merge_rq(struct request_queue
*rq
,
1597 static inline int blk_integrity_merge_bio(struct request_queue
*rq
,
1603 static inline bool blk_integrity_is_initialized(struct gendisk
*g
)
1608 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1610 struct block_device_operations
{
1611 int (*open
) (struct block_device
*, fmode_t
);
1612 void (*release
) (struct gendisk
*, fmode_t
);
1613 int (*rw_page
)(struct block_device
*, sector_t
, struct page
*, int rw
);
1614 int (*ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1615 int (*compat_ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1616 int (*direct_access
) (struct block_device
*, sector_t
,
1617 void **, unsigned long *);
1618 unsigned int (*check_events
) (struct gendisk
*disk
,
1619 unsigned int clearing
);
1620 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1621 int (*media_changed
) (struct gendisk
*);
1622 void (*unlock_native_capacity
) (struct gendisk
*);
1623 int (*revalidate_disk
) (struct gendisk
*);
1624 int (*getgeo
)(struct block_device
*, struct hd_geometry
*);
1625 /* this callback is with swap_lock and sometimes page table lock held */
1626 void (*swap_slot_free_notify
) (struct block_device
*, unsigned long);
1627 struct module
*owner
;
1630 extern int __blkdev_driver_ioctl(struct block_device
*, fmode_t
, unsigned int,
1632 extern int bdev_read_page(struct block_device
*, sector_t
, struct page
*);
1633 extern int bdev_write_page(struct block_device
*, sector_t
, struct page
*,
1634 struct writeback_control
*);
1635 #else /* CONFIG_BLOCK */
1637 struct block_device
;
1640 * stubs for when the block layer is configured out
1642 #define buffer_heads_over_limit 0
1644 static inline long nr_blockdev_pages(void)
1652 static inline void blk_start_plug(struct blk_plug
*plug
)
1656 static inline void blk_finish_plug(struct blk_plug
*plug
)
1660 static inline void blk_flush_plug(struct task_struct
*task
)
1664 static inline void blk_schedule_flush_plug(struct task_struct
*task
)
1669 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1674 static inline int blkdev_issue_flush(struct block_device
*bdev
, gfp_t gfp_mask
,
1675 sector_t
*error_sector
)
1680 #endif /* CONFIG_BLOCK */