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/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>
24 #include <linux/percpu-refcount.h>
25 #include <linux/scatterlist.h>
28 struct scsi_ioctl_command
;
31 struct elevator_queue
;
37 struct blk_flush_queue
;
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_DRV_PRIV
, /* driver defined types from here */
79 #define BLK_MAX_CDB 16
82 * Try to put the fields that are referenced together in the same cacheline.
84 * If you modify this structure, make sure to update blk_rq_init() and
85 * especially blk_mq_rq_ctx_init() to take care of the added fields.
88 struct list_head queuelist
;
90 struct call_single_data csd
;
91 unsigned long fifo_time
;
94 struct request_queue
*q
;
95 struct blk_mq_ctx
*mq_ctx
;
99 unsigned long atomic_flags
;
103 /* the following two fields are internal, NEVER access directly */
104 unsigned int __data_len
; /* total data len */
105 sector_t __sector
; /* sector cursor */
111 * The hash is used inside the scheduler, and killed once the
112 * request reaches the dispatch list. The ipi_list is only used
113 * to queue the request for softirq completion, which is long
114 * after the request has been unhashed (and even removed from
115 * the dispatch list).
118 struct hlist_node hash
; /* merge hash */
119 struct list_head ipi_list
;
123 * The rb_node is only used inside the io scheduler, requests
124 * are pruned when moved to the dispatch queue. So let the
125 * completion_data share space with the rb_node.
128 struct rb_node rb_node
; /* sort/lookup */
129 void *completion_data
;
133 * Three pointers are available for the IO schedulers, if they need
134 * more they have to dynamically allocate it. Flush requests are
135 * never put on the IO scheduler. So let the flush fields share
136 * space with the elevator data.
146 struct list_head list
;
147 rq_end_io_fn
*saved_end_io
;
151 struct gendisk
*rq_disk
;
152 struct hd_struct
*part
;
153 unsigned long start_time
;
154 #ifdef CONFIG_BLK_CGROUP
155 struct request_list
*rl
; /* rl this rq is alloced from */
156 unsigned long long start_time_ns
;
157 unsigned long long io_start_time_ns
; /* when passed to hardware */
159 /* Number of scatter-gather DMA addr+len pairs after
160 * physical address coalescing is performed.
162 unsigned short nr_phys_segments
;
163 #if defined(CONFIG_BLK_DEV_INTEGRITY)
164 unsigned short nr_integrity_segments
;
167 unsigned short ioprio
;
169 void *special
; /* opaque pointer available for LLD use */
175 * when request is used as a packet command carrier
177 unsigned char __cmd
[BLK_MAX_CDB
];
179 unsigned short cmd_len
;
181 unsigned int extra_len
; /* length of alignment and padding */
182 unsigned int sense_len
;
183 unsigned int resid_len
; /* residual count */
186 unsigned long deadline
;
187 struct list_head timeout_list
;
188 unsigned int timeout
;
192 * completion callback.
194 rq_end_io_fn
*end_io
;
198 struct request
*next_rq
;
201 static inline unsigned short req_get_ioprio(struct request
*req
)
206 #include <linux/elevator.h>
208 struct blk_queue_ctx
;
210 typedef void (request_fn_proc
) (struct request_queue
*q
);
211 typedef void (make_request_fn
) (struct request_queue
*q
, struct bio
*bio
);
212 typedef int (prep_rq_fn
) (struct request_queue
*, struct request
*);
213 typedef void (unprep_rq_fn
) (struct request_queue
*, struct request
*);
216 struct bvec_merge_data
{
217 struct block_device
*bi_bdev
;
222 typedef int (merge_bvec_fn
) (struct request_queue
*, struct bvec_merge_data
*,
224 typedef void (softirq_done_fn
)(struct request
*);
225 typedef int (dma_drain_needed_fn
)(struct request
*);
226 typedef int (lld_busy_fn
) (struct request_queue
*q
);
227 typedef int (bsg_job_fn
) (struct bsg_job
*);
229 enum blk_eh_timer_return
{
235 typedef enum blk_eh_timer_return (rq_timed_out_fn
)(struct request
*);
237 enum blk_queue_state
{
242 struct blk_queue_tag
{
243 struct request
**tag_index
; /* map of busy tags */
244 unsigned long *tag_map
; /* bit map of free/busy tags */
245 int busy
; /* current depth */
246 int max_depth
; /* what we will send to device */
247 int real_max_depth
; /* what the array can hold */
248 atomic_t refcnt
; /* map can be shared */
249 int alloc_policy
; /* tag allocation policy */
250 int next_tag
; /* next tag */
252 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
253 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
255 #define BLK_SCSI_MAX_CMDS (256)
256 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
258 struct queue_limits
{
259 unsigned long bounce_pfn
;
260 unsigned long seg_boundary_mask
;
262 unsigned int max_hw_sectors
;
263 unsigned int chunk_sectors
;
264 unsigned int max_sectors
;
265 unsigned int max_segment_size
;
266 unsigned int physical_block_size
;
267 unsigned int alignment_offset
;
270 unsigned int max_discard_sectors
;
271 unsigned int max_hw_discard_sectors
;
272 unsigned int max_write_same_sectors
;
273 unsigned int discard_granularity
;
274 unsigned int discard_alignment
;
276 unsigned short logical_block_size
;
277 unsigned short max_segments
;
278 unsigned short max_integrity_segments
;
280 unsigned char misaligned
;
281 unsigned char discard_misaligned
;
282 unsigned char cluster
;
283 unsigned char discard_zeroes_data
;
284 unsigned char raid_partial_stripes_expensive
;
287 struct request_queue
{
289 * Together with queue_head for cacheline sharing
291 struct list_head queue_head
;
292 struct request
*last_merge
;
293 struct elevator_queue
*elevator
;
294 int nr_rqs
[2]; /* # allocated [a]sync rqs */
295 int nr_rqs_elvpriv
; /* # allocated rqs w/ elvpriv */
298 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
299 * is used, root blkg allocates from @q->root_rl and all other
300 * blkgs from their own blkg->rl. Which one to use should be
301 * determined using bio_request_list().
303 struct request_list root_rl
;
305 request_fn_proc
*request_fn
;
306 make_request_fn
*make_request_fn
;
307 prep_rq_fn
*prep_rq_fn
;
308 unprep_rq_fn
*unprep_rq_fn
;
309 merge_bvec_fn
*merge_bvec_fn
;
310 softirq_done_fn
*softirq_done_fn
;
311 rq_timed_out_fn
*rq_timed_out_fn
;
312 dma_drain_needed_fn
*dma_drain_needed
;
313 lld_busy_fn
*lld_busy_fn
;
315 struct blk_mq_ops
*mq_ops
;
317 unsigned int *mq_map
;
320 struct blk_mq_ctx __percpu
*queue_ctx
;
321 unsigned int nr_queues
;
323 /* hw dispatch queues */
324 struct blk_mq_hw_ctx
**queue_hw_ctx
;
325 unsigned int nr_hw_queues
;
328 * Dispatch queue sorting
331 struct request
*boundary_rq
;
334 * Delayed queue handling
336 struct delayed_work delay_work
;
338 struct backing_dev_info backing_dev_info
;
341 * The queue owner gets to use this for whatever they like.
342 * ll_rw_blk doesn't touch it.
347 * various queue flags, see QUEUE_* below
349 unsigned long queue_flags
;
352 * ida allocated id for this queue. Used to index queues from
358 * queue needs bounce pages for pages above this limit
363 * protects queue structures from reentrancy. ->__queue_lock should
364 * _never_ be used directly, it is queue private. always use
367 spinlock_t __queue_lock
;
368 spinlock_t
*queue_lock
;
378 struct kobject mq_kobj
;
383 unsigned int nr_pending
;
389 unsigned long nr_requests
; /* Max # of requests */
390 unsigned int nr_congestion_on
;
391 unsigned int nr_congestion_off
;
392 unsigned int nr_batching
;
394 unsigned int dma_drain_size
;
395 void *dma_drain_buffer
;
396 unsigned int dma_pad_mask
;
397 unsigned int dma_alignment
;
399 struct blk_queue_tag
*queue_tags
;
400 struct list_head tag_busy_list
;
402 unsigned int nr_sorted
;
403 unsigned int in_flight
[2];
405 * Number of active block driver functions for which blk_drain_queue()
406 * must wait. Must be incremented around functions that unlock the
407 * queue_lock internally, e.g. scsi_request_fn().
409 unsigned int request_fn_active
;
411 unsigned int rq_timeout
;
412 struct timer_list timeout
;
413 struct list_head timeout_list
;
415 struct list_head icq_list
;
416 #ifdef CONFIG_BLK_CGROUP
417 DECLARE_BITMAP (blkcg_pols
, BLKCG_MAX_POLS
);
418 struct blkcg_gq
*root_blkg
;
419 struct list_head blkg_list
;
422 struct queue_limits limits
;
427 unsigned int sg_timeout
;
428 unsigned int sg_reserved_size
;
430 #ifdef CONFIG_BLK_DEV_IO_TRACE
431 struct blk_trace
*blk_trace
;
434 * for flush operations
436 unsigned int flush_flags
;
437 unsigned int flush_not_queueable
:1;
438 struct blk_flush_queue
*fq
;
440 struct list_head requeue_list
;
441 spinlock_t requeue_lock
;
442 struct work_struct requeue_work
;
444 struct mutex sysfs_lock
;
447 atomic_t mq_freeze_depth
;
449 #if defined(CONFIG_BLK_DEV_BSG)
450 bsg_job_fn
*bsg_job_fn
;
452 struct bsg_class_device bsg_dev
;
455 #ifdef CONFIG_BLK_DEV_THROTTLING
457 struct throtl_data
*td
;
459 struct rcu_head rcu_head
;
460 wait_queue_head_t mq_freeze_wq
;
461 struct percpu_ref mq_usage_counter
;
462 struct list_head all_q_node
;
464 struct blk_mq_tag_set
*tag_set
;
465 struct list_head tag_set_list
;
466 struct bio_set
*bio_split
;
469 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
470 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
471 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
472 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
473 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
474 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
475 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
476 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
477 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
478 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
479 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
480 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
481 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
482 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
483 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
484 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
485 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
486 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
487 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
488 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
489 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
490 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
491 #define QUEUE_FLAG_SG_GAPS 22 /* queue doesn't support SG gaps */
493 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
494 (1 << QUEUE_FLAG_STACKABLE) | \
495 (1 << QUEUE_FLAG_SAME_COMP) | \
496 (1 << QUEUE_FLAG_ADD_RANDOM))
498 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
499 (1 << QUEUE_FLAG_STACKABLE) | \
500 (1 << QUEUE_FLAG_SAME_COMP))
502 static inline void queue_lockdep_assert_held(struct request_queue
*q
)
505 lockdep_assert_held(q
->queue_lock
);
508 static inline void queue_flag_set_unlocked(unsigned int flag
,
509 struct request_queue
*q
)
511 __set_bit(flag
, &q
->queue_flags
);
514 static inline int queue_flag_test_and_clear(unsigned int flag
,
515 struct request_queue
*q
)
517 queue_lockdep_assert_held(q
);
519 if (test_bit(flag
, &q
->queue_flags
)) {
520 __clear_bit(flag
, &q
->queue_flags
);
527 static inline int queue_flag_test_and_set(unsigned int flag
,
528 struct request_queue
*q
)
530 queue_lockdep_assert_held(q
);
532 if (!test_bit(flag
, &q
->queue_flags
)) {
533 __set_bit(flag
, &q
->queue_flags
);
540 static inline void queue_flag_set(unsigned int flag
, struct request_queue
*q
)
542 queue_lockdep_assert_held(q
);
543 __set_bit(flag
, &q
->queue_flags
);
546 static inline void queue_flag_clear_unlocked(unsigned int flag
,
547 struct request_queue
*q
)
549 __clear_bit(flag
, &q
->queue_flags
);
552 static inline int queue_in_flight(struct request_queue
*q
)
554 return q
->in_flight
[0] + q
->in_flight
[1];
557 static inline void queue_flag_clear(unsigned int flag
, struct request_queue
*q
)
559 queue_lockdep_assert_held(q
);
560 __clear_bit(flag
, &q
->queue_flags
);
563 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
564 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
565 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
566 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
567 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
568 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
569 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
570 #define blk_queue_noxmerges(q) \
571 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
572 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
573 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
574 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
575 #define blk_queue_stackable(q) \
576 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
577 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
578 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
579 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
581 #define blk_noretry_request(rq) \
582 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
583 REQ_FAILFAST_DRIVER))
585 #define blk_account_rq(rq) \
586 (((rq)->cmd_flags & REQ_STARTED) && \
587 ((rq)->cmd_type == REQ_TYPE_FS))
589 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
590 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
591 /* rq->queuelist of dequeued request must be list_empty() */
592 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
594 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
596 #define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
599 * Driver can handle struct request, if it either has an old style
600 * request_fn defined, or is blk-mq based.
602 static inline bool queue_is_rq_based(struct request_queue
*q
)
604 return q
->request_fn
|| q
->mq_ops
;
607 static inline unsigned int blk_queue_cluster(struct request_queue
*q
)
609 return q
->limits
.cluster
;
613 * We regard a request as sync, if either a read or a sync write
615 static inline bool rw_is_sync(unsigned int rw_flags
)
617 return !(rw_flags
& REQ_WRITE
) || (rw_flags
& REQ_SYNC
);
620 static inline bool rq_is_sync(struct request
*rq
)
622 return rw_is_sync(rq
->cmd_flags
);
625 static inline bool blk_rl_full(struct request_list
*rl
, bool sync
)
627 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
629 return rl
->flags
& flag
;
632 static inline void blk_set_rl_full(struct request_list
*rl
, bool sync
)
634 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
639 static inline void blk_clear_rl_full(struct request_list
*rl
, bool sync
)
641 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
646 static inline bool rq_mergeable(struct request
*rq
)
648 if (rq
->cmd_type
!= REQ_TYPE_FS
)
651 if (rq
->cmd_flags
& REQ_NOMERGE_FLAGS
)
657 static inline bool blk_check_merge_flags(unsigned int flags1
,
660 if ((flags1
& REQ_DISCARD
) != (flags2
& REQ_DISCARD
))
663 if ((flags1
& REQ_SECURE
) != (flags2
& REQ_SECURE
))
666 if ((flags1
& REQ_WRITE_SAME
) != (flags2
& REQ_WRITE_SAME
))
672 static inline bool blk_write_same_mergeable(struct bio
*a
, struct bio
*b
)
674 if (bio_data(a
) == bio_data(b
))
681 * q->prep_rq_fn return values
683 #define BLKPREP_OK 0 /* serve it */
684 #define BLKPREP_KILL 1 /* fatal error, kill */
685 #define BLKPREP_DEFER 2 /* leave on queue */
687 extern unsigned long blk_max_low_pfn
, blk_max_pfn
;
690 * standard bounce addresses:
692 * BLK_BOUNCE_HIGH : bounce all highmem pages
693 * BLK_BOUNCE_ANY : don't bounce anything
694 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
697 #if BITS_PER_LONG == 32
698 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
700 #define BLK_BOUNCE_HIGH -1ULL
702 #define BLK_BOUNCE_ANY (-1ULL)
703 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
706 * default timeout for SG_IO if none specified
708 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
709 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
712 extern int init_emergency_isa_pool(void);
713 extern void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
);
715 static inline int init_emergency_isa_pool(void)
719 static inline void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
)
722 #endif /* CONFIG_MMU */
728 unsigned long offset
;
733 struct req_iterator
{
734 struct bvec_iter iter
;
738 /* This should not be used directly - use rq_for_each_segment */
739 #define for_each_bio(_bio) \
740 for (; _bio; _bio = _bio->bi_next)
741 #define __rq_for_each_bio(_bio, rq) \
743 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
745 #define rq_for_each_segment(bvl, _rq, _iter) \
746 __rq_for_each_bio(_iter.bio, _rq) \
747 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
749 #define rq_iter_last(bvec, _iter) \
750 (_iter.bio->bi_next == NULL && \
751 bio_iter_last(bvec, _iter.iter))
753 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
754 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
756 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
757 extern void rq_flush_dcache_pages(struct request
*rq
);
759 static inline void rq_flush_dcache_pages(struct request
*rq
)
764 extern int blk_register_queue(struct gendisk
*disk
);
765 extern void blk_unregister_queue(struct gendisk
*disk
);
766 extern void generic_make_request(struct bio
*bio
);
767 extern void blk_rq_init(struct request_queue
*q
, struct request
*rq
);
768 extern void blk_put_request(struct request
*);
769 extern void __blk_put_request(struct request_queue
*, struct request
*);
770 extern struct request
*blk_get_request(struct request_queue
*, int, gfp_t
);
771 extern struct request
*blk_make_request(struct request_queue
*, struct bio
*,
773 extern void blk_rq_set_block_pc(struct request
*);
774 extern void blk_requeue_request(struct request_queue
*, struct request
*);
775 extern void blk_add_request_payload(struct request
*rq
, struct page
*page
,
777 extern int blk_rq_check_limits(struct request_queue
*q
, struct request
*rq
);
778 extern int blk_lld_busy(struct request_queue
*q
);
779 extern int blk_rq_prep_clone(struct request
*rq
, struct request
*rq_src
,
780 struct bio_set
*bs
, gfp_t gfp_mask
,
781 int (*bio_ctr
)(struct bio
*, struct bio
*, void *),
783 extern void blk_rq_unprep_clone(struct request
*rq
);
784 extern int blk_insert_cloned_request(struct request_queue
*q
,
786 extern void blk_delay_queue(struct request_queue
*, unsigned long);
787 extern void blk_queue_split(struct request_queue
*, struct bio
**,
789 extern void blk_recount_segments(struct request_queue
*, struct bio
*);
790 extern int scsi_verify_blk_ioctl(struct block_device
*, unsigned int);
791 extern int scsi_cmd_blk_ioctl(struct block_device
*, fmode_t
,
792 unsigned int, void __user
*);
793 extern int scsi_cmd_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
794 unsigned int, void __user
*);
795 extern int sg_scsi_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
796 struct scsi_ioctl_command __user
*);
798 extern void blk_start_queue(struct request_queue
*q
);
799 extern void blk_stop_queue(struct request_queue
*q
);
800 extern void blk_sync_queue(struct request_queue
*q
);
801 extern void __blk_stop_queue(struct request_queue
*q
);
802 extern void __blk_run_queue(struct request_queue
*q
);
803 extern void __blk_run_queue_uncond(struct request_queue
*q
);
804 extern void blk_run_queue(struct request_queue
*);
805 extern void blk_run_queue_async(struct request_queue
*q
);
806 extern int blk_rq_map_user(struct request_queue
*, struct request
*,
807 struct rq_map_data
*, void __user
*, unsigned long,
809 extern int blk_rq_unmap_user(struct bio
*);
810 extern int blk_rq_map_kern(struct request_queue
*, struct request
*, void *, unsigned int, gfp_t
);
811 extern int blk_rq_map_user_iov(struct request_queue
*, struct request
*,
812 struct rq_map_data
*, const struct iov_iter
*,
814 extern int blk_execute_rq(struct request_queue
*, struct gendisk
*,
815 struct request
*, int);
816 extern void blk_execute_rq_nowait(struct request_queue
*, struct gendisk
*,
817 struct request
*, int, rq_end_io_fn
*);
819 static inline struct request_queue
*bdev_get_queue(struct block_device
*bdev
)
821 return bdev
->bd_disk
->queue
; /* this is never NULL */
825 * blk_rq_pos() : the current sector
826 * blk_rq_bytes() : bytes left in the entire request
827 * blk_rq_cur_bytes() : bytes left in the current segment
828 * blk_rq_err_bytes() : bytes left till the next error boundary
829 * blk_rq_sectors() : sectors left in the entire request
830 * blk_rq_cur_sectors() : sectors left in the current segment
832 static inline sector_t
blk_rq_pos(const struct request
*rq
)
837 static inline unsigned int blk_rq_bytes(const struct request
*rq
)
839 return rq
->__data_len
;
842 static inline int blk_rq_cur_bytes(const struct request
*rq
)
844 return rq
->bio
? bio_cur_bytes(rq
->bio
) : 0;
847 extern unsigned int blk_rq_err_bytes(const struct request
*rq
);
849 static inline unsigned int blk_rq_sectors(const struct request
*rq
)
851 return blk_rq_bytes(rq
) >> 9;
854 static inline unsigned int blk_rq_cur_sectors(const struct request
*rq
)
856 return blk_rq_cur_bytes(rq
) >> 9;
859 static inline unsigned int blk_queue_get_max_sectors(struct request_queue
*q
,
860 unsigned int cmd_flags
)
862 if (unlikely(cmd_flags
& REQ_DISCARD
))
863 return min(q
->limits
.max_discard_sectors
, UINT_MAX
>> 9);
865 if (unlikely(cmd_flags
& REQ_WRITE_SAME
))
866 return q
->limits
.max_write_same_sectors
;
868 return q
->limits
.max_sectors
;
872 * Return maximum size of a request at given offset. Only valid for
873 * file system requests.
875 static inline unsigned int blk_max_size_offset(struct request_queue
*q
,
878 if (!q
->limits
.chunk_sectors
)
879 return q
->limits
.max_sectors
;
881 return q
->limits
.chunk_sectors
-
882 (offset
& (q
->limits
.chunk_sectors
- 1));
885 static inline unsigned int blk_rq_get_max_sectors(struct request
*rq
)
887 struct request_queue
*q
= rq
->q
;
889 if (unlikely(rq
->cmd_type
== REQ_TYPE_BLOCK_PC
))
890 return q
->limits
.max_hw_sectors
;
892 if (!q
->limits
.chunk_sectors
|| (rq
->cmd_flags
& REQ_DISCARD
))
893 return blk_queue_get_max_sectors(q
, rq
->cmd_flags
);
895 return min(blk_max_size_offset(q
, blk_rq_pos(rq
)),
896 blk_queue_get_max_sectors(q
, rq
->cmd_flags
));
899 static inline unsigned int blk_rq_count_bios(struct request
*rq
)
901 unsigned int nr_bios
= 0;
904 __rq_for_each_bio(bio
, rq
)
911 * Request issue related functions.
913 extern struct request
*blk_peek_request(struct request_queue
*q
);
914 extern void blk_start_request(struct request
*rq
);
915 extern struct request
*blk_fetch_request(struct request_queue
*q
);
918 * Request completion related functions.
920 * blk_update_request() completes given number of bytes and updates
921 * the request without completing it.
923 * blk_end_request() and friends. __blk_end_request() must be called
924 * with the request queue spinlock acquired.
926 * Several drivers define their own end_request and call
927 * blk_end_request() for parts of the original function.
928 * This prevents code duplication in drivers.
930 extern bool blk_update_request(struct request
*rq
, int error
,
931 unsigned int nr_bytes
);
932 extern void blk_finish_request(struct request
*rq
, int error
);
933 extern bool blk_end_request(struct request
*rq
, int error
,
934 unsigned int nr_bytes
);
935 extern void blk_end_request_all(struct request
*rq
, int error
);
936 extern bool blk_end_request_cur(struct request
*rq
, int error
);
937 extern bool blk_end_request_err(struct request
*rq
, int error
);
938 extern bool __blk_end_request(struct request
*rq
, int error
,
939 unsigned int nr_bytes
);
940 extern void __blk_end_request_all(struct request
*rq
, int error
);
941 extern bool __blk_end_request_cur(struct request
*rq
, int error
);
942 extern bool __blk_end_request_err(struct request
*rq
, int error
);
944 extern void blk_complete_request(struct request
*);
945 extern void __blk_complete_request(struct request
*);
946 extern void blk_abort_request(struct request
*);
947 extern void blk_unprep_request(struct request
*);
950 * Access functions for manipulating queue properties
952 extern struct request_queue
*blk_init_queue_node(request_fn_proc
*rfn
,
953 spinlock_t
*lock
, int node_id
);
954 extern struct request_queue
*blk_init_queue(request_fn_proc
*, spinlock_t
*);
955 extern struct request_queue
*blk_init_allocated_queue(struct request_queue
*,
956 request_fn_proc
*, spinlock_t
*);
957 extern void blk_cleanup_queue(struct request_queue
*);
958 extern void blk_queue_make_request(struct request_queue
*, make_request_fn
*);
959 extern void blk_queue_bounce_limit(struct request_queue
*, u64
);
960 extern void blk_limits_max_hw_sectors(struct queue_limits
*, unsigned int);
961 extern void blk_queue_max_hw_sectors(struct request_queue
*, unsigned int);
962 extern void blk_queue_chunk_sectors(struct request_queue
*, unsigned int);
963 extern void blk_queue_max_segments(struct request_queue
*, unsigned short);
964 extern void blk_queue_max_segment_size(struct request_queue
*, unsigned int);
965 extern void blk_queue_max_discard_sectors(struct request_queue
*q
,
966 unsigned int max_discard_sectors
);
967 extern void blk_queue_max_write_same_sectors(struct request_queue
*q
,
968 unsigned int max_write_same_sectors
);
969 extern void blk_queue_logical_block_size(struct request_queue
*, unsigned short);
970 extern void blk_queue_physical_block_size(struct request_queue
*, unsigned int);
971 extern void blk_queue_alignment_offset(struct request_queue
*q
,
972 unsigned int alignment
);
973 extern void blk_limits_io_min(struct queue_limits
*limits
, unsigned int min
);
974 extern void blk_queue_io_min(struct request_queue
*q
, unsigned int min
);
975 extern void blk_limits_io_opt(struct queue_limits
*limits
, unsigned int opt
);
976 extern void blk_queue_io_opt(struct request_queue
*q
, unsigned int opt
);
977 extern void blk_set_default_limits(struct queue_limits
*lim
);
978 extern void blk_set_stacking_limits(struct queue_limits
*lim
);
979 extern int blk_stack_limits(struct queue_limits
*t
, struct queue_limits
*b
,
981 extern int bdev_stack_limits(struct queue_limits
*t
, struct block_device
*bdev
,
983 extern void disk_stack_limits(struct gendisk
*disk
, struct block_device
*bdev
,
985 extern void blk_queue_stack_limits(struct request_queue
*t
, struct request_queue
*b
);
986 extern void blk_queue_dma_pad(struct request_queue
*, unsigned int);
987 extern void blk_queue_update_dma_pad(struct request_queue
*, unsigned int);
988 extern int blk_queue_dma_drain(struct request_queue
*q
,
989 dma_drain_needed_fn
*dma_drain_needed
,
990 void *buf
, unsigned int size
);
991 extern void blk_queue_lld_busy(struct request_queue
*q
, lld_busy_fn
*fn
);
992 extern void blk_queue_segment_boundary(struct request_queue
*, unsigned long);
993 extern void blk_queue_prep_rq(struct request_queue
*, prep_rq_fn
*pfn
);
994 extern void blk_queue_unprep_rq(struct request_queue
*, unprep_rq_fn
*ufn
);
995 extern void blk_queue_merge_bvec(struct request_queue
*, merge_bvec_fn
*);
996 extern void blk_queue_dma_alignment(struct request_queue
*, int);
997 extern void blk_queue_update_dma_alignment(struct request_queue
*, int);
998 extern void blk_queue_softirq_done(struct request_queue
*, softirq_done_fn
*);
999 extern void blk_queue_rq_timed_out(struct request_queue
*, rq_timed_out_fn
*);
1000 extern void blk_queue_rq_timeout(struct request_queue
*, unsigned int);
1001 extern void blk_queue_flush(struct request_queue
*q
, unsigned int flush
);
1002 extern void blk_queue_flush_queueable(struct request_queue
*q
, bool queueable
);
1003 extern struct backing_dev_info
*blk_get_backing_dev_info(struct block_device
*bdev
);
1005 extern int blk_rq_map_sg(struct request_queue
*, struct request
*, struct scatterlist
*);
1006 extern void blk_dump_rq_flags(struct request
*, char *);
1007 extern long nr_blockdev_pages(void);
1009 bool __must_check
blk_get_queue(struct request_queue
*);
1010 struct request_queue
*blk_alloc_queue(gfp_t
);
1011 struct request_queue
*blk_alloc_queue_node(gfp_t
, int);
1012 extern void blk_put_queue(struct request_queue
*);
1013 extern void blk_set_queue_dying(struct request_queue
*);
1016 * block layer runtime pm functions
1019 extern void blk_pm_runtime_init(struct request_queue
*q
, struct device
*dev
);
1020 extern int blk_pre_runtime_suspend(struct request_queue
*q
);
1021 extern void blk_post_runtime_suspend(struct request_queue
*q
, int err
);
1022 extern void blk_pre_runtime_resume(struct request_queue
*q
);
1023 extern void blk_post_runtime_resume(struct request_queue
*q
, int err
);
1025 static inline void blk_pm_runtime_init(struct request_queue
*q
,
1026 struct device
*dev
) {}
1027 static inline int blk_pre_runtime_suspend(struct request_queue
*q
)
1031 static inline void blk_post_runtime_suspend(struct request_queue
*q
, int err
) {}
1032 static inline void blk_pre_runtime_resume(struct request_queue
*q
) {}
1033 static inline void blk_post_runtime_resume(struct request_queue
*q
, int err
) {}
1037 * blk_plug permits building a queue of related requests by holding the I/O
1038 * fragments for a short period. This allows merging of sequential requests
1039 * into single larger request. As the requests are moved from a per-task list to
1040 * the device's request_queue in a batch, this results in improved scalability
1041 * as the lock contention for request_queue lock is reduced.
1043 * It is ok not to disable preemption when adding the request to the plug list
1044 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1045 * the plug list when the task sleeps by itself. For details, please see
1046 * schedule() where blk_schedule_flush_plug() is called.
1049 struct list_head list
; /* requests */
1050 struct list_head mq_list
; /* blk-mq requests */
1051 struct list_head cb_list
; /* md requires an unplug callback */
1053 #define BLK_MAX_REQUEST_COUNT 16
1056 typedef void (*blk_plug_cb_fn
)(struct blk_plug_cb
*, bool);
1057 struct blk_plug_cb
{
1058 struct list_head list
;
1059 blk_plug_cb_fn callback
;
1062 extern struct blk_plug_cb
*blk_check_plugged(blk_plug_cb_fn unplug
,
1063 void *data
, int size
);
1064 extern void blk_start_plug(struct blk_plug
*);
1065 extern void blk_finish_plug(struct blk_plug
*);
1066 extern void blk_flush_plug_list(struct blk_plug
*, bool);
1068 static inline void blk_flush_plug(struct task_struct
*tsk
)
1070 struct blk_plug
*plug
= tsk
->plug
;
1073 blk_flush_plug_list(plug
, false);
1076 static inline void blk_schedule_flush_plug(struct task_struct
*tsk
)
1078 struct blk_plug
*plug
= tsk
->plug
;
1081 blk_flush_plug_list(plug
, true);
1084 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1086 struct blk_plug
*plug
= tsk
->plug
;
1089 (!list_empty(&plug
->list
) ||
1090 !list_empty(&plug
->mq_list
) ||
1091 !list_empty(&plug
->cb_list
));
1097 extern int blk_queue_start_tag(struct request_queue
*, struct request
*);
1098 extern struct request
*blk_queue_find_tag(struct request_queue
*, int);
1099 extern void blk_queue_end_tag(struct request_queue
*, struct request
*);
1100 extern int blk_queue_init_tags(struct request_queue
*, int, struct blk_queue_tag
*, int);
1101 extern void blk_queue_free_tags(struct request_queue
*);
1102 extern int blk_queue_resize_tags(struct request_queue
*, int);
1103 extern void blk_queue_invalidate_tags(struct request_queue
*);
1104 extern struct blk_queue_tag
*blk_init_tags(int, int);
1105 extern void blk_free_tags(struct blk_queue_tag
*);
1107 static inline struct request
*blk_map_queue_find_tag(struct blk_queue_tag
*bqt
,
1110 if (unlikely(bqt
== NULL
|| tag
>= bqt
->real_max_depth
))
1112 return bqt
->tag_index
[tag
];
1115 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1117 extern int blkdev_issue_flush(struct block_device
*, gfp_t
, sector_t
*);
1118 extern int blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
1119 sector_t nr_sects
, gfp_t gfp_mask
, unsigned long flags
);
1120 extern int blkdev_issue_write_same(struct block_device
*bdev
, sector_t sector
,
1121 sector_t nr_sects
, gfp_t gfp_mask
, struct page
*page
);
1122 extern int blkdev_issue_zeroout(struct block_device
*bdev
, sector_t sector
,
1123 sector_t nr_sects
, gfp_t gfp_mask
, bool discard
);
1124 static inline int sb_issue_discard(struct super_block
*sb
, sector_t block
,
1125 sector_t nr_blocks
, gfp_t gfp_mask
, unsigned long flags
)
1127 return blkdev_issue_discard(sb
->s_bdev
, block
<< (sb
->s_blocksize_bits
- 9),
1128 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1131 static inline int sb_issue_zeroout(struct super_block
*sb
, sector_t block
,
1132 sector_t nr_blocks
, gfp_t gfp_mask
)
1134 return blkdev_issue_zeroout(sb
->s_bdev
,
1135 block
<< (sb
->s_blocksize_bits
- 9),
1136 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1140 extern int blk_verify_command(unsigned char *cmd
, fmode_t has_write_perm
);
1142 enum blk_default_limits
{
1143 BLK_MAX_SEGMENTS
= 128,
1144 BLK_SAFE_MAX_SECTORS
= 255,
1145 BLK_MAX_SEGMENT_SIZE
= 65536,
1146 BLK_SEG_BOUNDARY_MASK
= 0xFFFFFFFFUL
,
1149 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1151 static inline unsigned long queue_bounce_pfn(struct request_queue
*q
)
1153 return q
->limits
.bounce_pfn
;
1156 static inline unsigned long queue_segment_boundary(struct request_queue
*q
)
1158 return q
->limits
.seg_boundary_mask
;
1161 static inline unsigned int queue_max_sectors(struct request_queue
*q
)
1163 return q
->limits
.max_sectors
;
1166 static inline unsigned int queue_max_hw_sectors(struct request_queue
*q
)
1168 return q
->limits
.max_hw_sectors
;
1171 static inline unsigned short queue_max_segments(struct request_queue
*q
)
1173 return q
->limits
.max_segments
;
1176 static inline unsigned int queue_max_segment_size(struct request_queue
*q
)
1178 return q
->limits
.max_segment_size
;
1181 static inline unsigned short queue_logical_block_size(struct request_queue
*q
)
1185 if (q
&& q
->limits
.logical_block_size
)
1186 retval
= q
->limits
.logical_block_size
;
1191 static inline unsigned short bdev_logical_block_size(struct block_device
*bdev
)
1193 return queue_logical_block_size(bdev_get_queue(bdev
));
1196 static inline unsigned int queue_physical_block_size(struct request_queue
*q
)
1198 return q
->limits
.physical_block_size
;
1201 static inline unsigned int bdev_physical_block_size(struct block_device
*bdev
)
1203 return queue_physical_block_size(bdev_get_queue(bdev
));
1206 static inline unsigned int queue_io_min(struct request_queue
*q
)
1208 return q
->limits
.io_min
;
1211 static inline int bdev_io_min(struct block_device
*bdev
)
1213 return queue_io_min(bdev_get_queue(bdev
));
1216 static inline unsigned int queue_io_opt(struct request_queue
*q
)
1218 return q
->limits
.io_opt
;
1221 static inline int bdev_io_opt(struct block_device
*bdev
)
1223 return queue_io_opt(bdev_get_queue(bdev
));
1226 static inline int queue_alignment_offset(struct request_queue
*q
)
1228 if (q
->limits
.misaligned
)
1231 return q
->limits
.alignment_offset
;
1234 static inline int queue_limit_alignment_offset(struct queue_limits
*lim
, sector_t sector
)
1236 unsigned int granularity
= max(lim
->physical_block_size
, lim
->io_min
);
1237 unsigned int alignment
= sector_div(sector
, granularity
>> 9) << 9;
1239 return (granularity
+ lim
->alignment_offset
- alignment
) % granularity
;
1242 static inline int bdev_alignment_offset(struct block_device
*bdev
)
1244 struct request_queue
*q
= bdev_get_queue(bdev
);
1246 if (q
->limits
.misaligned
)
1249 if (bdev
!= bdev
->bd_contains
)
1250 return bdev
->bd_part
->alignment_offset
;
1252 return q
->limits
.alignment_offset
;
1255 static inline int queue_discard_alignment(struct request_queue
*q
)
1257 if (q
->limits
.discard_misaligned
)
1260 return q
->limits
.discard_alignment
;
1263 static inline int queue_limit_discard_alignment(struct queue_limits
*lim
, sector_t sector
)
1265 unsigned int alignment
, granularity
, offset
;
1267 if (!lim
->max_discard_sectors
)
1270 /* Why are these in bytes, not sectors? */
1271 alignment
= lim
->discard_alignment
>> 9;
1272 granularity
= lim
->discard_granularity
>> 9;
1276 /* Offset of the partition start in 'granularity' sectors */
1277 offset
= sector_div(sector
, granularity
);
1279 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1280 offset
= (granularity
+ alignment
- offset
) % granularity
;
1282 /* Turn it back into bytes, gaah */
1286 static inline int bdev_discard_alignment(struct block_device
*bdev
)
1288 struct request_queue
*q
= bdev_get_queue(bdev
);
1290 if (bdev
!= bdev
->bd_contains
)
1291 return bdev
->bd_part
->discard_alignment
;
1293 return q
->limits
.discard_alignment
;
1296 static inline unsigned int queue_discard_zeroes_data(struct request_queue
*q
)
1298 if (q
->limits
.max_discard_sectors
&& q
->limits
.discard_zeroes_data
== 1)
1304 static inline unsigned int bdev_discard_zeroes_data(struct block_device
*bdev
)
1306 return queue_discard_zeroes_data(bdev_get_queue(bdev
));
1309 static inline unsigned int bdev_write_same(struct block_device
*bdev
)
1311 struct request_queue
*q
= bdev_get_queue(bdev
);
1314 return q
->limits
.max_write_same_sectors
;
1319 static inline int queue_dma_alignment(struct request_queue
*q
)
1321 return q
? q
->dma_alignment
: 511;
1324 static inline int blk_rq_aligned(struct request_queue
*q
, unsigned long addr
,
1327 unsigned int alignment
= queue_dma_alignment(q
) | q
->dma_pad_mask
;
1328 return !(addr
& alignment
) && !(len
& alignment
);
1331 /* assumes size > 256 */
1332 static inline unsigned int blksize_bits(unsigned int size
)
1334 unsigned int bits
= 8;
1338 } while (size
> 256);
1342 static inline unsigned int block_size(struct block_device
*bdev
)
1344 return bdev
->bd_block_size
;
1347 static inline bool queue_flush_queueable(struct request_queue
*q
)
1349 return !q
->flush_not_queueable
;
1352 typedef struct {struct page
*v
;} Sector
;
1354 unsigned char *read_dev_sector(struct block_device
*, sector_t
, Sector
*);
1356 static inline void put_dev_sector(Sector p
)
1358 page_cache_release(p
.v
);
1362 int kblockd_schedule_work(struct work_struct
*work
);
1363 int kblockd_schedule_delayed_work(struct delayed_work
*dwork
, unsigned long delay
);
1364 int kblockd_schedule_delayed_work_on(int cpu
, struct delayed_work
*dwork
, unsigned long delay
);
1366 #ifdef CONFIG_BLK_CGROUP
1368 * This should not be using sched_clock(). A real patch is in progress
1369 * to fix this up, until that is in place we need to disable preemption
1370 * around sched_clock() in this function and set_io_start_time_ns().
1372 static inline void set_start_time_ns(struct request
*req
)
1375 req
->start_time_ns
= sched_clock();
1379 static inline void set_io_start_time_ns(struct request
*req
)
1382 req
->io_start_time_ns
= sched_clock();
1386 static inline uint64_t rq_start_time_ns(struct request
*req
)
1388 return req
->start_time_ns
;
1391 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1393 return req
->io_start_time_ns
;
1396 static inline void set_start_time_ns(struct request
*req
) {}
1397 static inline void set_io_start_time_ns(struct request
*req
) {}
1398 static inline uint64_t rq_start_time_ns(struct request
*req
)
1402 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1408 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1409 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1410 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1411 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1413 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1415 enum blk_integrity_flags
{
1416 BLK_INTEGRITY_VERIFY
= 1 << 0,
1417 BLK_INTEGRITY_GENERATE
= 1 << 1,
1418 BLK_INTEGRITY_DEVICE_CAPABLE
= 1 << 2,
1419 BLK_INTEGRITY_IP_CHECKSUM
= 1 << 3,
1422 struct blk_integrity_iter
{
1426 unsigned int data_size
;
1427 unsigned short interval
;
1428 const char *disk_name
;
1431 typedef int (integrity_processing_fn
) (struct blk_integrity_iter
*);
1433 struct blk_integrity
{
1434 integrity_processing_fn
*generate_fn
;
1435 integrity_processing_fn
*verify_fn
;
1437 unsigned short flags
;
1438 unsigned short tuple_size
;
1439 unsigned short interval
;
1440 unsigned short tag_size
;
1444 struct kobject kobj
;
1447 extern bool blk_integrity_is_initialized(struct gendisk
*);
1448 extern int blk_integrity_register(struct gendisk
*, struct blk_integrity
*);
1449 extern void blk_integrity_unregister(struct gendisk
*);
1450 extern int blk_integrity_compare(struct gendisk
*, struct gendisk
*);
1451 extern int blk_rq_map_integrity_sg(struct request_queue
*, struct bio
*,
1452 struct scatterlist
*);
1453 extern int blk_rq_count_integrity_sg(struct request_queue
*, struct bio
*);
1454 extern bool blk_integrity_merge_rq(struct request_queue
*, struct request
*,
1456 extern bool blk_integrity_merge_bio(struct request_queue
*, struct request
*,
1460 struct blk_integrity
*bdev_get_integrity(struct block_device
*bdev
)
1462 return bdev
->bd_disk
->integrity
;
1465 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1467 return disk
->integrity
;
1470 static inline bool blk_integrity_rq(struct request
*rq
)
1472 return rq
->cmd_flags
& REQ_INTEGRITY
;
1475 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1478 q
->limits
.max_integrity_segments
= segs
;
1481 static inline unsigned short
1482 queue_max_integrity_segments(struct request_queue
*q
)
1484 return q
->limits
.max_integrity_segments
;
1487 #else /* CONFIG_BLK_DEV_INTEGRITY */
1490 struct block_device
;
1492 struct blk_integrity
;
1494 static inline int blk_integrity_rq(struct request
*rq
)
1498 static inline int blk_rq_count_integrity_sg(struct request_queue
*q
,
1503 static inline int blk_rq_map_integrity_sg(struct request_queue
*q
,
1505 struct scatterlist
*s
)
1509 static inline struct blk_integrity
*bdev_get_integrity(struct block_device
*b
)
1513 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1517 static inline int blk_integrity_compare(struct gendisk
*a
, struct gendisk
*b
)
1521 static inline int blk_integrity_register(struct gendisk
*d
,
1522 struct blk_integrity
*b
)
1526 static inline void blk_integrity_unregister(struct gendisk
*d
)
1529 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1533 static inline unsigned short queue_max_integrity_segments(struct request_queue
*q
)
1537 static inline bool blk_integrity_merge_rq(struct request_queue
*rq
,
1543 static inline bool blk_integrity_merge_bio(struct request_queue
*rq
,
1549 static inline bool blk_integrity_is_initialized(struct gendisk
*g
)
1554 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1556 struct block_device_operations
{
1557 int (*open
) (struct block_device
*, fmode_t
);
1558 void (*release
) (struct gendisk
*, fmode_t
);
1559 int (*rw_page
)(struct block_device
*, sector_t
, struct page
*, int rw
);
1560 int (*ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1561 int (*compat_ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1562 long (*direct_access
)(struct block_device
*, sector_t
,
1563 void **, unsigned long *pfn
, long size
);
1564 unsigned int (*check_events
) (struct gendisk
*disk
,
1565 unsigned int clearing
);
1566 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1567 int (*media_changed
) (struct gendisk
*);
1568 void (*unlock_native_capacity
) (struct gendisk
*);
1569 int (*revalidate_disk
) (struct gendisk
*);
1570 int (*getgeo
)(struct block_device
*, struct hd_geometry
*);
1571 /* this callback is with swap_lock and sometimes page table lock held */
1572 void (*swap_slot_free_notify
) (struct block_device
*, unsigned long);
1573 struct module
*owner
;
1576 extern int __blkdev_driver_ioctl(struct block_device
*, fmode_t
, unsigned int,
1578 extern int bdev_read_page(struct block_device
*, sector_t
, struct page
*);
1579 extern int bdev_write_page(struct block_device
*, sector_t
, struct page
*,
1580 struct writeback_control
*);
1581 extern long bdev_direct_access(struct block_device
*, sector_t
, void **addr
,
1582 unsigned long *pfn
, long size
);
1583 #else /* CONFIG_BLOCK */
1585 struct block_device
;
1588 * stubs for when the block layer is configured out
1590 #define buffer_heads_over_limit 0
1592 static inline long nr_blockdev_pages(void)
1600 static inline void blk_start_plug(struct blk_plug
*plug
)
1604 static inline void blk_finish_plug(struct blk_plug
*plug
)
1608 static inline void blk_flush_plug(struct task_struct
*task
)
1612 static inline void blk_schedule_flush_plug(struct task_struct
*task
)
1617 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1622 static inline int blkdev_issue_flush(struct block_device
*bdev
, gfp_t gfp_mask
,
1623 sector_t
*error_sector
)
1628 #endif /* CONFIG_BLOCK */