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 #define req_op(req) (op_from_rq_bits((req)->cmd_flags))
204 #define req_set_op(req, op) ((req)->cmd_flags |= op)
205 #define req_set_op_attrs(req, op, flags) do { \
206 req_set_op(req, op); \
207 (req)->cmd_flags |= flags; \
210 static inline unsigned short req_get_ioprio(struct request
*req
)
215 #include <linux/elevator.h>
217 struct blk_queue_ctx
;
219 typedef void (request_fn_proc
) (struct request_queue
*q
);
220 typedef blk_qc_t (make_request_fn
) (struct request_queue
*q
, struct bio
*bio
);
221 typedef int (prep_rq_fn
) (struct request_queue
*, struct request
*);
222 typedef void (unprep_rq_fn
) (struct request_queue
*, struct request
*);
225 typedef void (softirq_done_fn
)(struct request
*);
226 typedef int (dma_drain_needed_fn
)(struct request
*);
227 typedef int (lld_busy_fn
) (struct request_queue
*q
);
228 typedef int (bsg_job_fn
) (struct bsg_job
*);
230 enum blk_eh_timer_return
{
236 typedef enum blk_eh_timer_return (rq_timed_out_fn
)(struct request
*);
238 enum blk_queue_state
{
243 struct blk_queue_tag
{
244 struct request
**tag_index
; /* map of busy tags */
245 unsigned long *tag_map
; /* bit map of free/busy tags */
246 int busy
; /* current depth */
247 int max_depth
; /* what we will send to device */
248 int real_max_depth
; /* what the array can hold */
249 atomic_t refcnt
; /* map can be shared */
250 int alloc_policy
; /* tag allocation policy */
251 int next_tag
; /* next tag */
253 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
254 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
256 #define BLK_SCSI_MAX_CMDS (256)
257 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
259 struct queue_limits
{
260 unsigned long bounce_pfn
;
261 unsigned long seg_boundary_mask
;
262 unsigned long virt_boundary_mask
;
264 unsigned int max_hw_sectors
;
265 unsigned int max_dev_sectors
;
266 unsigned int chunk_sectors
;
267 unsigned int max_sectors
;
268 unsigned int max_segment_size
;
269 unsigned int physical_block_size
;
270 unsigned int alignment_offset
;
273 unsigned int max_discard_sectors
;
274 unsigned int max_hw_discard_sectors
;
275 unsigned int max_write_same_sectors
;
276 unsigned int discard_granularity
;
277 unsigned int discard_alignment
;
279 unsigned short logical_block_size
;
280 unsigned short max_segments
;
281 unsigned short max_integrity_segments
;
283 unsigned char misaligned
;
284 unsigned char discard_misaligned
;
285 unsigned char cluster
;
286 unsigned char discard_zeroes_data
;
287 unsigned char raid_partial_stripes_expensive
;
290 struct request_queue
{
292 * Together with queue_head for cacheline sharing
294 struct list_head queue_head
;
295 struct request
*last_merge
;
296 struct elevator_queue
*elevator
;
297 int nr_rqs
[2]; /* # allocated [a]sync rqs */
298 int nr_rqs_elvpriv
; /* # allocated rqs w/ elvpriv */
301 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
302 * is used, root blkg allocates from @q->root_rl and all other
303 * blkgs from their own blkg->rl. Which one to use should be
304 * determined using bio_request_list().
306 struct request_list root_rl
;
308 request_fn_proc
*request_fn
;
309 make_request_fn
*make_request_fn
;
310 prep_rq_fn
*prep_rq_fn
;
311 unprep_rq_fn
*unprep_rq_fn
;
312 softirq_done_fn
*softirq_done_fn
;
313 rq_timed_out_fn
*rq_timed_out_fn
;
314 dma_drain_needed_fn
*dma_drain_needed
;
315 lld_busy_fn
*lld_busy_fn
;
317 struct blk_mq_ops
*mq_ops
;
319 unsigned int *mq_map
;
322 struct blk_mq_ctx __percpu
*queue_ctx
;
323 unsigned int nr_queues
;
325 /* hw dispatch queues */
326 struct blk_mq_hw_ctx
**queue_hw_ctx
;
327 unsigned int nr_hw_queues
;
330 * Dispatch queue sorting
333 struct request
*boundary_rq
;
336 * Delayed queue handling
338 struct delayed_work delay_work
;
340 struct backing_dev_info backing_dev_info
;
343 * The queue owner gets to use this for whatever they like.
344 * ll_rw_blk doesn't touch it.
349 * various queue flags, see QUEUE_* below
351 unsigned long queue_flags
;
354 * ida allocated id for this queue. Used to index queues from
360 * queue needs bounce pages for pages above this limit
365 * protects queue structures from reentrancy. ->__queue_lock should
366 * _never_ be used directly, it is queue private. always use
369 spinlock_t __queue_lock
;
370 spinlock_t
*queue_lock
;
380 struct kobject mq_kobj
;
382 #ifdef CONFIG_BLK_DEV_INTEGRITY
383 struct blk_integrity integrity
;
384 #endif /* CONFIG_BLK_DEV_INTEGRITY */
389 unsigned int nr_pending
;
395 unsigned long nr_requests
; /* Max # of requests */
396 unsigned int nr_congestion_on
;
397 unsigned int nr_congestion_off
;
398 unsigned int nr_batching
;
400 unsigned int dma_drain_size
;
401 void *dma_drain_buffer
;
402 unsigned int dma_pad_mask
;
403 unsigned int dma_alignment
;
405 struct blk_queue_tag
*queue_tags
;
406 struct list_head tag_busy_list
;
408 unsigned int nr_sorted
;
409 unsigned int in_flight
[2];
411 * Number of active block driver functions for which blk_drain_queue()
412 * must wait. Must be incremented around functions that unlock the
413 * queue_lock internally, e.g. scsi_request_fn().
415 unsigned int request_fn_active
;
417 unsigned int rq_timeout
;
418 struct timer_list timeout
;
419 struct work_struct timeout_work
;
420 struct list_head timeout_list
;
422 struct list_head icq_list
;
423 #ifdef CONFIG_BLK_CGROUP
424 DECLARE_BITMAP (blkcg_pols
, BLKCG_MAX_POLS
);
425 struct blkcg_gq
*root_blkg
;
426 struct list_head blkg_list
;
429 struct queue_limits limits
;
434 unsigned int sg_timeout
;
435 unsigned int sg_reserved_size
;
437 #ifdef CONFIG_BLK_DEV_IO_TRACE
438 struct blk_trace
*blk_trace
;
441 * for flush operations
443 struct blk_flush_queue
*fq
;
445 struct list_head requeue_list
;
446 spinlock_t requeue_lock
;
447 struct work_struct requeue_work
;
449 struct mutex sysfs_lock
;
452 atomic_t mq_freeze_depth
;
454 #if defined(CONFIG_BLK_DEV_BSG)
455 bsg_job_fn
*bsg_job_fn
;
457 struct bsg_class_device bsg_dev
;
460 #ifdef CONFIG_BLK_DEV_THROTTLING
462 struct throtl_data
*td
;
464 struct rcu_head rcu_head
;
465 wait_queue_head_t mq_freeze_wq
;
466 struct percpu_ref q_usage_counter
;
467 struct list_head all_q_node
;
469 struct blk_mq_tag_set
*tag_set
;
470 struct list_head tag_set_list
;
471 struct bio_set
*bio_split
;
473 bool mq_sysfs_init_done
;
476 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
477 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
478 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
479 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
480 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
481 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
482 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
483 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
484 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
485 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
486 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
487 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
488 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
489 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
490 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
491 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
492 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
493 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
494 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
495 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
496 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
497 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
498 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
499 #define QUEUE_FLAG_WC 23 /* Write back caching */
500 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
501 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
503 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
504 (1 << QUEUE_FLAG_STACKABLE) | \
505 (1 << QUEUE_FLAG_SAME_COMP) | \
506 (1 << QUEUE_FLAG_ADD_RANDOM))
508 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
509 (1 << QUEUE_FLAG_STACKABLE) | \
510 (1 << QUEUE_FLAG_SAME_COMP) | \
511 (1 << QUEUE_FLAG_POLL))
513 static inline void queue_lockdep_assert_held(struct request_queue
*q
)
516 lockdep_assert_held(q
->queue_lock
);
519 static inline void queue_flag_set_unlocked(unsigned int flag
,
520 struct request_queue
*q
)
522 __set_bit(flag
, &q
->queue_flags
);
525 static inline int queue_flag_test_and_clear(unsigned int flag
,
526 struct request_queue
*q
)
528 queue_lockdep_assert_held(q
);
530 if (test_bit(flag
, &q
->queue_flags
)) {
531 __clear_bit(flag
, &q
->queue_flags
);
538 static inline int queue_flag_test_and_set(unsigned int flag
,
539 struct request_queue
*q
)
541 queue_lockdep_assert_held(q
);
543 if (!test_bit(flag
, &q
->queue_flags
)) {
544 __set_bit(flag
, &q
->queue_flags
);
551 static inline void queue_flag_set(unsigned int flag
, struct request_queue
*q
)
553 queue_lockdep_assert_held(q
);
554 __set_bit(flag
, &q
->queue_flags
);
557 static inline void queue_flag_clear_unlocked(unsigned int flag
,
558 struct request_queue
*q
)
560 __clear_bit(flag
, &q
->queue_flags
);
563 static inline int queue_in_flight(struct request_queue
*q
)
565 return q
->in_flight
[0] + q
->in_flight
[1];
568 static inline void queue_flag_clear(unsigned int flag
, struct request_queue
*q
)
570 queue_lockdep_assert_held(q
);
571 __clear_bit(flag
, &q
->queue_flags
);
574 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
575 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
576 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
577 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
578 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
579 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
580 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
581 #define blk_queue_noxmerges(q) \
582 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
583 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
584 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
585 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
586 #define blk_queue_stackable(q) \
587 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
588 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
589 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
590 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
592 #define blk_noretry_request(rq) \
593 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
594 REQ_FAILFAST_DRIVER))
596 #define blk_account_rq(rq) \
597 (((rq)->cmd_flags & REQ_STARTED) && \
598 ((rq)->cmd_type == REQ_TYPE_FS))
600 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
601 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
602 /* rq->queuelist of dequeued request must be list_empty() */
603 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
605 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
607 #define rq_data_dir(rq) \
608 (op_is_write(op_from_rq_bits(rq->cmd_flags)) ? WRITE : READ)
611 * Driver can handle struct request, if it either has an old style
612 * request_fn defined, or is blk-mq based.
614 static inline bool queue_is_rq_based(struct request_queue
*q
)
616 return q
->request_fn
|| q
->mq_ops
;
619 static inline unsigned int blk_queue_cluster(struct request_queue
*q
)
621 return q
->limits
.cluster
;
625 * We regard a request as sync, if either a read or a sync write
627 static inline bool rw_is_sync(unsigned int rw_flags
)
629 return !(rw_flags
& REQ_WRITE
) || (rw_flags
& REQ_SYNC
);
632 static inline bool rq_is_sync(struct request
*rq
)
634 return rw_is_sync(rq
->cmd_flags
);
637 static inline bool blk_rl_full(struct request_list
*rl
, bool sync
)
639 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
641 return rl
->flags
& flag
;
644 static inline void blk_set_rl_full(struct request_list
*rl
, bool sync
)
646 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
651 static inline void blk_clear_rl_full(struct request_list
*rl
, bool sync
)
653 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
658 static inline bool rq_mergeable(struct request
*rq
)
660 if (rq
->cmd_type
!= REQ_TYPE_FS
)
663 if (rq
->cmd_flags
& REQ_NOMERGE_FLAGS
)
669 static inline bool blk_check_merge_flags(unsigned int flags1
,
672 if ((flags1
& REQ_DISCARD
) != (flags2
& REQ_DISCARD
))
675 if ((flags1
& REQ_SECURE
) != (flags2
& REQ_SECURE
))
678 if ((flags1
& REQ_WRITE_SAME
) != (flags2
& REQ_WRITE_SAME
))
684 static inline bool blk_write_same_mergeable(struct bio
*a
, struct bio
*b
)
686 if (bio_data(a
) == bio_data(b
))
693 * q->prep_rq_fn return values
696 BLKPREP_OK
, /* serve it */
697 BLKPREP_KILL
, /* fatal error, kill, return -EIO */
698 BLKPREP_DEFER
, /* leave on queue */
699 BLKPREP_INVALID
, /* invalid command, kill, return -EREMOTEIO */
702 extern unsigned long blk_max_low_pfn
, blk_max_pfn
;
705 * standard bounce addresses:
707 * BLK_BOUNCE_HIGH : bounce all highmem pages
708 * BLK_BOUNCE_ANY : don't bounce anything
709 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
712 #if BITS_PER_LONG == 32
713 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
715 #define BLK_BOUNCE_HIGH -1ULL
717 #define BLK_BOUNCE_ANY (-1ULL)
718 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
721 * default timeout for SG_IO if none specified
723 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
724 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
727 extern int init_emergency_isa_pool(void);
728 extern void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
);
730 static inline int init_emergency_isa_pool(void)
734 static inline void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
)
737 #endif /* CONFIG_MMU */
743 unsigned long offset
;
748 struct req_iterator
{
749 struct bvec_iter iter
;
753 /* This should not be used directly - use rq_for_each_segment */
754 #define for_each_bio(_bio) \
755 for (; _bio; _bio = _bio->bi_next)
756 #define __rq_for_each_bio(_bio, rq) \
758 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
760 #define rq_for_each_segment(bvl, _rq, _iter) \
761 __rq_for_each_bio(_iter.bio, _rq) \
762 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
764 #define rq_iter_last(bvec, _iter) \
765 (_iter.bio->bi_next == NULL && \
766 bio_iter_last(bvec, _iter.iter))
768 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
769 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
771 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
772 extern void rq_flush_dcache_pages(struct request
*rq
);
774 static inline void rq_flush_dcache_pages(struct request
*rq
)
780 #define vfs_msg(sb, level, fmt, ...) \
781 __vfs_msg(sb, level, fmt, ##__VA_ARGS__)
783 #define vfs_msg(sb, level, fmt, ...) \
785 no_printk(fmt, ##__VA_ARGS__); \
786 __vfs_msg(sb, "", " "); \
790 extern int blk_register_queue(struct gendisk
*disk
);
791 extern void blk_unregister_queue(struct gendisk
*disk
);
792 extern blk_qc_t
generic_make_request(struct bio
*bio
);
793 extern void blk_rq_init(struct request_queue
*q
, struct request
*rq
);
794 extern void blk_put_request(struct request
*);
795 extern void __blk_put_request(struct request_queue
*, struct request
*);
796 extern struct request
*blk_get_request(struct request_queue
*, int, gfp_t
);
797 extern struct request
*blk_make_request(struct request_queue
*, struct bio
*,
799 extern void blk_rq_set_block_pc(struct request
*);
800 extern void blk_requeue_request(struct request_queue
*, struct request
*);
801 extern void blk_add_request_payload(struct request
*rq
, struct page
*page
,
802 int offset
, unsigned int len
);
803 extern int blk_lld_busy(struct request_queue
*q
);
804 extern int blk_rq_prep_clone(struct request
*rq
, struct request
*rq_src
,
805 struct bio_set
*bs
, gfp_t gfp_mask
,
806 int (*bio_ctr
)(struct bio
*, struct bio
*, void *),
808 extern void blk_rq_unprep_clone(struct request
*rq
);
809 extern int blk_insert_cloned_request(struct request_queue
*q
,
811 extern void blk_delay_queue(struct request_queue
*, unsigned long);
812 extern void blk_queue_split(struct request_queue
*, struct bio
**,
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 int blk_queue_enter(struct request_queue
*q
, bool nowait
);
824 extern void blk_queue_exit(struct request_queue
*q
);
825 extern void blk_start_queue(struct request_queue
*q
);
826 extern void blk_start_queue_async(struct request_queue
*q
);
827 extern void blk_stop_queue(struct request_queue
*q
);
828 extern void blk_sync_queue(struct request_queue
*q
);
829 extern void __blk_stop_queue(struct request_queue
*q
);
830 extern void __blk_run_queue(struct request_queue
*q
);
831 extern void __blk_run_queue_uncond(struct request_queue
*q
);
832 extern void blk_run_queue(struct request_queue
*);
833 extern void blk_run_queue_async(struct request_queue
*q
);
834 extern int blk_rq_map_user(struct request_queue
*, struct request
*,
835 struct rq_map_data
*, void __user
*, unsigned long,
837 extern int blk_rq_unmap_user(struct bio
*);
838 extern int blk_rq_map_kern(struct request_queue
*, struct request
*, void *, unsigned int, gfp_t
);
839 extern int blk_rq_map_user_iov(struct request_queue
*, struct request
*,
840 struct rq_map_data
*, const struct iov_iter
*,
842 extern int blk_execute_rq(struct request_queue
*, struct gendisk
*,
843 struct request
*, int);
844 extern void blk_execute_rq_nowait(struct request_queue
*, struct gendisk
*,
845 struct request
*, int, rq_end_io_fn
*);
847 bool blk_poll(struct request_queue
*q
, blk_qc_t cookie
);
849 static inline struct request_queue
*bdev_get_queue(struct block_device
*bdev
)
851 return bdev
->bd_disk
->queue
; /* this is never NULL */
855 * blk_rq_pos() : the current sector
856 * blk_rq_bytes() : bytes left in the entire request
857 * blk_rq_cur_bytes() : bytes left in the current segment
858 * blk_rq_err_bytes() : bytes left till the next error boundary
859 * blk_rq_sectors() : sectors left in the entire request
860 * blk_rq_cur_sectors() : sectors left in the current segment
862 static inline sector_t
blk_rq_pos(const struct request
*rq
)
867 static inline unsigned int blk_rq_bytes(const struct request
*rq
)
869 return rq
->__data_len
;
872 static inline int blk_rq_cur_bytes(const struct request
*rq
)
874 return rq
->bio
? bio_cur_bytes(rq
->bio
) : 0;
877 extern unsigned int blk_rq_err_bytes(const struct request
*rq
);
879 static inline unsigned int blk_rq_sectors(const struct request
*rq
)
881 return blk_rq_bytes(rq
) >> 9;
884 static inline unsigned int blk_rq_cur_sectors(const struct request
*rq
)
886 return blk_rq_cur_bytes(rq
) >> 9;
889 static inline unsigned int blk_queue_get_max_sectors(struct request_queue
*q
,
890 unsigned int cmd_flags
)
892 if (unlikely(cmd_flags
& REQ_DISCARD
))
893 return min(q
->limits
.max_discard_sectors
, UINT_MAX
>> 9);
895 if (unlikely(cmd_flags
& REQ_WRITE_SAME
))
896 return q
->limits
.max_write_same_sectors
;
898 return q
->limits
.max_sectors
;
902 * Return maximum size of a request at given offset. Only valid for
903 * file system requests.
905 static inline unsigned int blk_max_size_offset(struct request_queue
*q
,
908 if (!q
->limits
.chunk_sectors
)
909 return q
->limits
.max_sectors
;
911 return q
->limits
.chunk_sectors
-
912 (offset
& (q
->limits
.chunk_sectors
- 1));
915 static inline unsigned int blk_rq_get_max_sectors(struct request
*rq
)
917 struct request_queue
*q
= rq
->q
;
919 if (unlikely(rq
->cmd_type
!= REQ_TYPE_FS
))
920 return q
->limits
.max_hw_sectors
;
922 if (!q
->limits
.chunk_sectors
|| (rq
->cmd_flags
& REQ_DISCARD
))
923 return blk_queue_get_max_sectors(q
, rq
->cmd_flags
);
925 return min(blk_max_size_offset(q
, blk_rq_pos(rq
)),
926 blk_queue_get_max_sectors(q
, rq
->cmd_flags
));
929 static inline unsigned int blk_rq_count_bios(struct request
*rq
)
931 unsigned int nr_bios
= 0;
934 __rq_for_each_bio(bio
, rq
)
941 * Request issue related functions.
943 extern struct request
*blk_peek_request(struct request_queue
*q
);
944 extern void blk_start_request(struct request
*rq
);
945 extern struct request
*blk_fetch_request(struct request_queue
*q
);
948 * Request completion related functions.
950 * blk_update_request() completes given number of bytes and updates
951 * the request without completing it.
953 * blk_end_request() and friends. __blk_end_request() must be called
954 * with the request queue spinlock acquired.
956 * Several drivers define their own end_request and call
957 * blk_end_request() for parts of the original function.
958 * This prevents code duplication in drivers.
960 extern bool blk_update_request(struct request
*rq
, int error
,
961 unsigned int nr_bytes
);
962 extern void blk_finish_request(struct request
*rq
, int error
);
963 extern bool blk_end_request(struct request
*rq
, int error
,
964 unsigned int nr_bytes
);
965 extern void blk_end_request_all(struct request
*rq
, int error
);
966 extern bool blk_end_request_cur(struct request
*rq
, int error
);
967 extern bool blk_end_request_err(struct request
*rq
, int error
);
968 extern bool __blk_end_request(struct request
*rq
, int error
,
969 unsigned int nr_bytes
);
970 extern void __blk_end_request_all(struct request
*rq
, int error
);
971 extern bool __blk_end_request_cur(struct request
*rq
, int error
);
972 extern bool __blk_end_request_err(struct request
*rq
, int error
);
974 extern void blk_complete_request(struct request
*);
975 extern void __blk_complete_request(struct request
*);
976 extern void blk_abort_request(struct request
*);
977 extern void blk_unprep_request(struct request
*);
980 * Access functions for manipulating queue properties
982 extern struct request_queue
*blk_init_queue_node(request_fn_proc
*rfn
,
983 spinlock_t
*lock
, int node_id
);
984 extern struct request_queue
*blk_init_queue(request_fn_proc
*, spinlock_t
*);
985 extern struct request_queue
*blk_init_allocated_queue(struct request_queue
*,
986 request_fn_proc
*, spinlock_t
*);
987 extern void blk_cleanup_queue(struct request_queue
*);
988 extern void blk_queue_make_request(struct request_queue
*, make_request_fn
*);
989 extern void blk_queue_bounce_limit(struct request_queue
*, u64
);
990 extern void blk_queue_max_hw_sectors(struct request_queue
*, unsigned int);
991 extern void blk_queue_chunk_sectors(struct request_queue
*, unsigned int);
992 extern void blk_queue_max_segments(struct request_queue
*, unsigned short);
993 extern void blk_queue_max_segment_size(struct request_queue
*, unsigned int);
994 extern void blk_queue_max_discard_sectors(struct request_queue
*q
,
995 unsigned int max_discard_sectors
);
996 extern void blk_queue_max_write_same_sectors(struct request_queue
*q
,
997 unsigned int max_write_same_sectors
);
998 extern void blk_queue_logical_block_size(struct request_queue
*, unsigned short);
999 extern void blk_queue_physical_block_size(struct request_queue
*, unsigned int);
1000 extern void blk_queue_alignment_offset(struct request_queue
*q
,
1001 unsigned int alignment
);
1002 extern void blk_limits_io_min(struct queue_limits
*limits
, unsigned int min
);
1003 extern void blk_queue_io_min(struct request_queue
*q
, unsigned int min
);
1004 extern void blk_limits_io_opt(struct queue_limits
*limits
, unsigned int opt
);
1005 extern void blk_queue_io_opt(struct request_queue
*q
, unsigned int opt
);
1006 extern void blk_set_default_limits(struct queue_limits
*lim
);
1007 extern void blk_set_stacking_limits(struct queue_limits
*lim
);
1008 extern int blk_stack_limits(struct queue_limits
*t
, struct queue_limits
*b
,
1010 extern int bdev_stack_limits(struct queue_limits
*t
, struct block_device
*bdev
,
1012 extern void disk_stack_limits(struct gendisk
*disk
, struct block_device
*bdev
,
1014 extern void blk_queue_stack_limits(struct request_queue
*t
, struct request_queue
*b
);
1015 extern void blk_queue_dma_pad(struct request_queue
*, unsigned int);
1016 extern void blk_queue_update_dma_pad(struct request_queue
*, unsigned int);
1017 extern int blk_queue_dma_drain(struct request_queue
*q
,
1018 dma_drain_needed_fn
*dma_drain_needed
,
1019 void *buf
, unsigned int size
);
1020 extern void blk_queue_lld_busy(struct request_queue
*q
, lld_busy_fn
*fn
);
1021 extern void blk_queue_segment_boundary(struct request_queue
*, unsigned long);
1022 extern void blk_queue_virt_boundary(struct request_queue
*, unsigned long);
1023 extern void blk_queue_prep_rq(struct request_queue
*, prep_rq_fn
*pfn
);
1024 extern void blk_queue_unprep_rq(struct request_queue
*, unprep_rq_fn
*ufn
);
1025 extern void blk_queue_dma_alignment(struct request_queue
*, int);
1026 extern void blk_queue_update_dma_alignment(struct request_queue
*, int);
1027 extern void blk_queue_softirq_done(struct request_queue
*, softirq_done_fn
*);
1028 extern void blk_queue_rq_timed_out(struct request_queue
*, rq_timed_out_fn
*);
1029 extern void blk_queue_rq_timeout(struct request_queue
*, unsigned int);
1030 extern void blk_queue_flush_queueable(struct request_queue
*q
, bool queueable
);
1031 extern void blk_queue_write_cache(struct request_queue
*q
, bool enabled
, bool fua
);
1032 extern struct backing_dev_info
*blk_get_backing_dev_info(struct block_device
*bdev
);
1034 extern int blk_rq_map_sg(struct request_queue
*, struct request
*, struct scatterlist
*);
1035 extern void blk_dump_rq_flags(struct request
*, char *);
1036 extern long nr_blockdev_pages(void);
1038 bool __must_check
blk_get_queue(struct request_queue
*);
1039 struct request_queue
*blk_alloc_queue(gfp_t
);
1040 struct request_queue
*blk_alloc_queue_node(gfp_t
, int);
1041 extern void blk_put_queue(struct request_queue
*);
1042 extern void blk_set_queue_dying(struct request_queue
*);
1045 * block layer runtime pm functions
1048 extern void blk_pm_runtime_init(struct request_queue
*q
, struct device
*dev
);
1049 extern int blk_pre_runtime_suspend(struct request_queue
*q
);
1050 extern void blk_post_runtime_suspend(struct request_queue
*q
, int err
);
1051 extern void blk_pre_runtime_resume(struct request_queue
*q
);
1052 extern void blk_post_runtime_resume(struct request_queue
*q
, int err
);
1053 extern void blk_set_runtime_active(struct request_queue
*q
);
1055 static inline void blk_pm_runtime_init(struct request_queue
*q
,
1056 struct device
*dev
) {}
1057 static inline int blk_pre_runtime_suspend(struct request_queue
*q
)
1061 static inline void blk_post_runtime_suspend(struct request_queue
*q
, int err
) {}
1062 static inline void blk_pre_runtime_resume(struct request_queue
*q
) {}
1063 static inline void blk_post_runtime_resume(struct request_queue
*q
, int err
) {}
1064 extern inline void blk_set_runtime_active(struct request_queue
*q
) {}
1068 * blk_plug permits building a queue of related requests by holding the I/O
1069 * fragments for a short period. This allows merging of sequential requests
1070 * into single larger request. As the requests are moved from a per-task list to
1071 * the device's request_queue in a batch, this results in improved scalability
1072 * as the lock contention for request_queue lock is reduced.
1074 * It is ok not to disable preemption when adding the request to the plug list
1075 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1076 * the plug list when the task sleeps by itself. For details, please see
1077 * schedule() where blk_schedule_flush_plug() is called.
1080 struct list_head list
; /* requests */
1081 struct list_head mq_list
; /* blk-mq requests */
1082 struct list_head cb_list
; /* md requires an unplug callback */
1084 #define BLK_MAX_REQUEST_COUNT 16
1087 typedef void (*blk_plug_cb_fn
)(struct blk_plug_cb
*, bool);
1088 struct blk_plug_cb
{
1089 struct list_head list
;
1090 blk_plug_cb_fn callback
;
1093 extern struct blk_plug_cb
*blk_check_plugged(blk_plug_cb_fn unplug
,
1094 void *data
, int size
);
1095 extern void blk_start_plug(struct blk_plug
*);
1096 extern void blk_finish_plug(struct blk_plug
*);
1097 extern void blk_flush_plug_list(struct blk_plug
*, bool);
1099 static inline void blk_flush_plug(struct task_struct
*tsk
)
1101 struct blk_plug
*plug
= tsk
->plug
;
1104 blk_flush_plug_list(plug
, false);
1107 static inline void blk_schedule_flush_plug(struct task_struct
*tsk
)
1109 struct blk_plug
*plug
= tsk
->plug
;
1112 blk_flush_plug_list(plug
, true);
1115 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1117 struct blk_plug
*plug
= tsk
->plug
;
1120 (!list_empty(&plug
->list
) ||
1121 !list_empty(&plug
->mq_list
) ||
1122 !list_empty(&plug
->cb_list
));
1128 extern int blk_queue_start_tag(struct request_queue
*, struct request
*);
1129 extern struct request
*blk_queue_find_tag(struct request_queue
*, int);
1130 extern void blk_queue_end_tag(struct request_queue
*, struct request
*);
1131 extern int blk_queue_init_tags(struct request_queue
*, int, struct blk_queue_tag
*, int);
1132 extern void blk_queue_free_tags(struct request_queue
*);
1133 extern int blk_queue_resize_tags(struct request_queue
*, int);
1134 extern void blk_queue_invalidate_tags(struct request_queue
*);
1135 extern struct blk_queue_tag
*blk_init_tags(int, int);
1136 extern void blk_free_tags(struct blk_queue_tag
*);
1138 static inline struct request
*blk_map_queue_find_tag(struct blk_queue_tag
*bqt
,
1141 if (unlikely(bqt
== NULL
|| tag
>= bqt
->real_max_depth
))
1143 return bqt
->tag_index
[tag
];
1146 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1148 extern int blkdev_issue_flush(struct block_device
*, gfp_t
, sector_t
*);
1149 extern int blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
1150 sector_t nr_sects
, gfp_t gfp_mask
, unsigned long flags
);
1151 extern int __blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
1152 sector_t nr_sects
, gfp_t gfp_mask
, int op_flags
,
1154 extern int blkdev_issue_write_same(struct block_device
*bdev
, sector_t sector
,
1155 sector_t nr_sects
, gfp_t gfp_mask
, struct page
*page
);
1156 extern int blkdev_issue_zeroout(struct block_device
*bdev
, sector_t sector
,
1157 sector_t nr_sects
, gfp_t gfp_mask
, bool discard
);
1158 static inline int sb_issue_discard(struct super_block
*sb
, sector_t block
,
1159 sector_t nr_blocks
, gfp_t gfp_mask
, unsigned long flags
)
1161 return blkdev_issue_discard(sb
->s_bdev
, block
<< (sb
->s_blocksize_bits
- 9),
1162 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1165 static inline int sb_issue_zeroout(struct super_block
*sb
, sector_t block
,
1166 sector_t nr_blocks
, gfp_t gfp_mask
)
1168 return blkdev_issue_zeroout(sb
->s_bdev
,
1169 block
<< (sb
->s_blocksize_bits
- 9),
1170 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1174 extern int blk_verify_command(unsigned char *cmd
, fmode_t has_write_perm
);
1176 enum blk_default_limits
{
1177 BLK_MAX_SEGMENTS
= 128,
1178 BLK_SAFE_MAX_SECTORS
= 255,
1179 BLK_DEF_MAX_SECTORS
= 2560,
1180 BLK_MAX_SEGMENT_SIZE
= 65536,
1181 BLK_SEG_BOUNDARY_MASK
= 0xFFFFFFFFUL
,
1184 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1186 static inline unsigned long queue_bounce_pfn(struct request_queue
*q
)
1188 return q
->limits
.bounce_pfn
;
1191 static inline unsigned long queue_segment_boundary(struct request_queue
*q
)
1193 return q
->limits
.seg_boundary_mask
;
1196 static inline unsigned long queue_virt_boundary(struct request_queue
*q
)
1198 return q
->limits
.virt_boundary_mask
;
1201 static inline unsigned int queue_max_sectors(struct request_queue
*q
)
1203 return q
->limits
.max_sectors
;
1206 static inline unsigned int queue_max_hw_sectors(struct request_queue
*q
)
1208 return q
->limits
.max_hw_sectors
;
1211 static inline unsigned short queue_max_segments(struct request_queue
*q
)
1213 return q
->limits
.max_segments
;
1216 static inline unsigned int queue_max_segment_size(struct request_queue
*q
)
1218 return q
->limits
.max_segment_size
;
1221 static inline unsigned short queue_logical_block_size(struct request_queue
*q
)
1225 if (q
&& q
->limits
.logical_block_size
)
1226 retval
= q
->limits
.logical_block_size
;
1231 static inline unsigned short bdev_logical_block_size(struct block_device
*bdev
)
1233 return queue_logical_block_size(bdev_get_queue(bdev
));
1236 static inline unsigned int queue_physical_block_size(struct request_queue
*q
)
1238 return q
->limits
.physical_block_size
;
1241 static inline unsigned int bdev_physical_block_size(struct block_device
*bdev
)
1243 return queue_physical_block_size(bdev_get_queue(bdev
));
1246 static inline unsigned int queue_io_min(struct request_queue
*q
)
1248 return q
->limits
.io_min
;
1251 static inline int bdev_io_min(struct block_device
*bdev
)
1253 return queue_io_min(bdev_get_queue(bdev
));
1256 static inline unsigned int queue_io_opt(struct request_queue
*q
)
1258 return q
->limits
.io_opt
;
1261 static inline int bdev_io_opt(struct block_device
*bdev
)
1263 return queue_io_opt(bdev_get_queue(bdev
));
1266 static inline int queue_alignment_offset(struct request_queue
*q
)
1268 if (q
->limits
.misaligned
)
1271 return q
->limits
.alignment_offset
;
1274 static inline int queue_limit_alignment_offset(struct queue_limits
*lim
, sector_t sector
)
1276 unsigned int granularity
= max(lim
->physical_block_size
, lim
->io_min
);
1277 unsigned int alignment
= sector_div(sector
, granularity
>> 9) << 9;
1279 return (granularity
+ lim
->alignment_offset
- alignment
) % granularity
;
1282 static inline int bdev_alignment_offset(struct block_device
*bdev
)
1284 struct request_queue
*q
= bdev_get_queue(bdev
);
1286 if (q
->limits
.misaligned
)
1289 if (bdev
!= bdev
->bd_contains
)
1290 return bdev
->bd_part
->alignment_offset
;
1292 return q
->limits
.alignment_offset
;
1295 static inline int queue_discard_alignment(struct request_queue
*q
)
1297 if (q
->limits
.discard_misaligned
)
1300 return q
->limits
.discard_alignment
;
1303 static inline int queue_limit_discard_alignment(struct queue_limits
*lim
, sector_t sector
)
1305 unsigned int alignment
, granularity
, offset
;
1307 if (!lim
->max_discard_sectors
)
1310 /* Why are these in bytes, not sectors? */
1311 alignment
= lim
->discard_alignment
>> 9;
1312 granularity
= lim
->discard_granularity
>> 9;
1316 /* Offset of the partition start in 'granularity' sectors */
1317 offset
= sector_div(sector
, granularity
);
1319 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1320 offset
= (granularity
+ alignment
- offset
) % granularity
;
1322 /* Turn it back into bytes, gaah */
1326 static inline int bdev_discard_alignment(struct block_device
*bdev
)
1328 struct request_queue
*q
= bdev_get_queue(bdev
);
1330 if (bdev
!= bdev
->bd_contains
)
1331 return bdev
->bd_part
->discard_alignment
;
1333 return q
->limits
.discard_alignment
;
1336 static inline unsigned int queue_discard_zeroes_data(struct request_queue
*q
)
1338 if (q
->limits
.max_discard_sectors
&& q
->limits
.discard_zeroes_data
== 1)
1344 static inline unsigned int bdev_discard_zeroes_data(struct block_device
*bdev
)
1346 return queue_discard_zeroes_data(bdev_get_queue(bdev
));
1349 static inline unsigned int bdev_write_same(struct block_device
*bdev
)
1351 struct request_queue
*q
= bdev_get_queue(bdev
);
1354 return q
->limits
.max_write_same_sectors
;
1359 static inline int queue_dma_alignment(struct request_queue
*q
)
1361 return q
? q
->dma_alignment
: 511;
1364 static inline int blk_rq_aligned(struct request_queue
*q
, unsigned long addr
,
1367 unsigned int alignment
= queue_dma_alignment(q
) | q
->dma_pad_mask
;
1368 return !(addr
& alignment
) && !(len
& alignment
);
1371 /* assumes size > 256 */
1372 static inline unsigned int blksize_bits(unsigned int size
)
1374 unsigned int bits
= 8;
1378 } while (size
> 256);
1382 static inline unsigned int block_size(struct block_device
*bdev
)
1384 return bdev
->bd_block_size
;
1387 static inline bool queue_flush_queueable(struct request_queue
*q
)
1389 return !test_bit(QUEUE_FLAG_FLUSH_NQ
, &q
->queue_flags
);
1392 typedef struct {struct page
*v
;} Sector
;
1394 unsigned char *read_dev_sector(struct block_device
*, sector_t
, Sector
*);
1396 static inline void put_dev_sector(Sector p
)
1401 static inline bool __bvec_gap_to_prev(struct request_queue
*q
,
1402 struct bio_vec
*bprv
, unsigned int offset
)
1405 ((bprv
->bv_offset
+ bprv
->bv_len
) & queue_virt_boundary(q
));
1409 * Check if adding a bio_vec after bprv with offset would create a gap in
1410 * the SG list. Most drivers don't care about this, but some do.
1412 static inline bool bvec_gap_to_prev(struct request_queue
*q
,
1413 struct bio_vec
*bprv
, unsigned int offset
)
1415 if (!queue_virt_boundary(q
))
1417 return __bvec_gap_to_prev(q
, bprv
, offset
);
1420 static inline bool bio_will_gap(struct request_queue
*q
, struct bio
*prev
,
1423 if (bio_has_data(prev
) && queue_virt_boundary(q
)) {
1424 struct bio_vec pb
, nb
;
1426 bio_get_last_bvec(prev
, &pb
);
1427 bio_get_first_bvec(next
, &nb
);
1429 return __bvec_gap_to_prev(q
, &pb
, nb
.bv_offset
);
1435 static inline bool req_gap_back_merge(struct request
*req
, struct bio
*bio
)
1437 return bio_will_gap(req
->q
, req
->biotail
, bio
);
1440 static inline bool req_gap_front_merge(struct request
*req
, struct bio
*bio
)
1442 return bio_will_gap(req
->q
, bio
, req
->bio
);
1446 int kblockd_schedule_work(struct work_struct
*work
);
1447 int kblockd_schedule_delayed_work(struct delayed_work
*dwork
, unsigned long delay
);
1448 int kblockd_schedule_delayed_work_on(int cpu
, struct delayed_work
*dwork
, unsigned long delay
);
1450 #ifdef CONFIG_BLK_CGROUP
1452 * This should not be using sched_clock(). A real patch is in progress
1453 * to fix this up, until that is in place we need to disable preemption
1454 * around sched_clock() in this function and set_io_start_time_ns().
1456 static inline void set_start_time_ns(struct request
*req
)
1459 req
->start_time_ns
= sched_clock();
1463 static inline void set_io_start_time_ns(struct request
*req
)
1466 req
->io_start_time_ns
= sched_clock();
1470 static inline uint64_t rq_start_time_ns(struct request
*req
)
1472 return req
->start_time_ns
;
1475 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1477 return req
->io_start_time_ns
;
1480 static inline void set_start_time_ns(struct request
*req
) {}
1481 static inline void set_io_start_time_ns(struct request
*req
) {}
1482 static inline uint64_t rq_start_time_ns(struct request
*req
)
1486 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1492 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1493 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1494 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1495 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1497 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1499 enum blk_integrity_flags
{
1500 BLK_INTEGRITY_VERIFY
= 1 << 0,
1501 BLK_INTEGRITY_GENERATE
= 1 << 1,
1502 BLK_INTEGRITY_DEVICE_CAPABLE
= 1 << 2,
1503 BLK_INTEGRITY_IP_CHECKSUM
= 1 << 3,
1506 struct blk_integrity_iter
{
1510 unsigned int data_size
;
1511 unsigned short interval
;
1512 const char *disk_name
;
1515 typedef int (integrity_processing_fn
) (struct blk_integrity_iter
*);
1517 struct blk_integrity_profile
{
1518 integrity_processing_fn
*generate_fn
;
1519 integrity_processing_fn
*verify_fn
;
1523 extern void blk_integrity_register(struct gendisk
*, struct blk_integrity
*);
1524 extern void blk_integrity_unregister(struct gendisk
*);
1525 extern int blk_integrity_compare(struct gendisk
*, struct gendisk
*);
1526 extern int blk_rq_map_integrity_sg(struct request_queue
*, struct bio
*,
1527 struct scatterlist
*);
1528 extern int blk_rq_count_integrity_sg(struct request_queue
*, struct bio
*);
1529 extern bool blk_integrity_merge_rq(struct request_queue
*, struct request
*,
1531 extern bool blk_integrity_merge_bio(struct request_queue
*, struct request
*,
1534 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1536 struct blk_integrity
*bi
= &disk
->queue
->integrity
;
1545 struct blk_integrity
*bdev_get_integrity(struct block_device
*bdev
)
1547 return blk_get_integrity(bdev
->bd_disk
);
1550 static inline bool blk_integrity_rq(struct request
*rq
)
1552 return rq
->cmd_flags
& REQ_INTEGRITY
;
1555 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1558 q
->limits
.max_integrity_segments
= segs
;
1561 static inline unsigned short
1562 queue_max_integrity_segments(struct request_queue
*q
)
1564 return q
->limits
.max_integrity_segments
;
1567 static inline bool integrity_req_gap_back_merge(struct request
*req
,
1570 struct bio_integrity_payload
*bip
= bio_integrity(req
->bio
);
1571 struct bio_integrity_payload
*bip_next
= bio_integrity(next
);
1573 return bvec_gap_to_prev(req
->q
, &bip
->bip_vec
[bip
->bip_vcnt
- 1],
1574 bip_next
->bip_vec
[0].bv_offset
);
1577 static inline bool integrity_req_gap_front_merge(struct request
*req
,
1580 struct bio_integrity_payload
*bip
= bio_integrity(bio
);
1581 struct bio_integrity_payload
*bip_next
= bio_integrity(req
->bio
);
1583 return bvec_gap_to_prev(req
->q
, &bip
->bip_vec
[bip
->bip_vcnt
- 1],
1584 bip_next
->bip_vec
[0].bv_offset
);
1587 #else /* CONFIG_BLK_DEV_INTEGRITY */
1590 struct block_device
;
1592 struct blk_integrity
;
1594 static inline int blk_integrity_rq(struct request
*rq
)
1598 static inline int blk_rq_count_integrity_sg(struct request_queue
*q
,
1603 static inline int blk_rq_map_integrity_sg(struct request_queue
*q
,
1605 struct scatterlist
*s
)
1609 static inline struct blk_integrity
*bdev_get_integrity(struct block_device
*b
)
1613 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1617 static inline int blk_integrity_compare(struct gendisk
*a
, struct gendisk
*b
)
1621 static inline void blk_integrity_register(struct gendisk
*d
,
1622 struct blk_integrity
*b
)
1625 static inline void blk_integrity_unregister(struct gendisk
*d
)
1628 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1632 static inline unsigned short queue_max_integrity_segments(struct request_queue
*q
)
1636 static inline bool blk_integrity_merge_rq(struct request_queue
*rq
,
1642 static inline bool blk_integrity_merge_bio(struct request_queue
*rq
,
1649 static inline bool integrity_req_gap_back_merge(struct request
*req
,
1654 static inline bool integrity_req_gap_front_merge(struct request
*req
,
1660 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1663 * struct blk_dax_ctl - control and output parameters for ->direct_access
1664 * @sector: (input) offset relative to a block_device
1665 * @addr: (output) kernel virtual address for @sector populated by driver
1666 * @pfn: (output) page frame number for @addr populated by driver
1667 * @size: (input) number of bytes requested
1669 struct blk_dax_ctl
{
1676 struct block_device_operations
{
1677 int (*open
) (struct block_device
*, fmode_t
);
1678 void (*release
) (struct gendisk
*, fmode_t
);
1679 int (*rw_page
)(struct block_device
*, sector_t
, struct page
*, int rw
);
1680 int (*ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1681 int (*compat_ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1682 long (*direct_access
)(struct block_device
*, sector_t
, void __pmem
**,
1684 unsigned int (*check_events
) (struct gendisk
*disk
,
1685 unsigned int clearing
);
1686 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1687 int (*media_changed
) (struct gendisk
*);
1688 void (*unlock_native_capacity
) (struct gendisk
*);
1689 int (*revalidate_disk
) (struct gendisk
*);
1690 int (*getgeo
)(struct block_device
*, struct hd_geometry
*);
1691 /* this callback is with swap_lock and sometimes page table lock held */
1692 void (*swap_slot_free_notify
) (struct block_device
*, unsigned long);
1693 struct module
*owner
;
1694 const struct pr_ops
*pr_ops
;
1697 extern int __blkdev_driver_ioctl(struct block_device
*, fmode_t
, unsigned int,
1699 extern int bdev_read_page(struct block_device
*, sector_t
, struct page
*);
1700 extern int bdev_write_page(struct block_device
*, sector_t
, struct page
*,
1701 struct writeback_control
*);
1702 extern long bdev_direct_access(struct block_device
*, struct blk_dax_ctl
*);
1703 extern int bdev_dax_supported(struct super_block
*, int);
1704 extern bool bdev_dax_capable(struct block_device
*);
1705 #else /* CONFIG_BLOCK */
1707 struct block_device
;
1710 * stubs for when the block layer is configured out
1712 #define buffer_heads_over_limit 0
1714 static inline long nr_blockdev_pages(void)
1722 static inline void blk_start_plug(struct blk_plug
*plug
)
1726 static inline void blk_finish_plug(struct blk_plug
*plug
)
1730 static inline void blk_flush_plug(struct task_struct
*task
)
1734 static inline void blk_schedule_flush_plug(struct task_struct
*task
)
1739 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1744 static inline int blkdev_issue_flush(struct block_device
*bdev
, gfp_t gfp_mask
,
1745 sector_t
*error_sector
)
1750 #endif /* CONFIG_BLOCK */