1 #ifndef _LINUX_BLKDEV_H
2 #define _LINUX_BLKDEV_H
4 #include <linux/sched.h>
8 #include <linux/major.h>
9 #include <linux/genhd.h>
10 #include <linux/list.h>
11 #include <linux/llist.h>
12 #include <linux/timer.h>
13 #include <linux/workqueue.h>
14 #include <linux/pagemap.h>
15 #include <linux/backing-dev.h>
16 #include <linux/wait.h>
17 #include <linux/mempool.h>
18 #include <linux/bio.h>
19 #include <linux/stringify.h>
20 #include <linux/gfp.h>
21 #include <linux/bsg.h>
22 #include <linux/smp.h>
23 #include <linux/rcupdate.h>
24 #include <linux/percpu-refcount.h>
26 #include <asm/scatterlist.h>
29 struct scsi_ioctl_command
;
32 struct elevator_queue
;
33 struct request_pm_state
;
39 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_PM_SUSPEND
, /* suspend request */
79 REQ_TYPE_PM_RESUME
, /* resume request */
80 REQ_TYPE_PM_SHUTDOWN
, /* shutdown request */
81 REQ_TYPE_DRV_PRIV
, /* driver defined types from here */
84 #define BLK_MAX_CDB 16
87 * Try to put the fields that are referenced together in the same cacheline.
89 * If you modify this structure, make sure to update blk_rq_init() and
90 * especially blk_mq_rq_ctx_init() to take care of the added fields.
93 struct list_head queuelist
;
95 struct call_single_data csd
;
96 unsigned long fifo_time
;
99 struct request_queue
*q
;
100 struct blk_mq_ctx
*mq_ctx
;
104 unsigned long atomic_flags
;
108 /* the following two fields are internal, NEVER access directly */
109 unsigned int __data_len
; /* total data len */
110 sector_t __sector
; /* sector cursor */
116 * The hash is used inside the scheduler, and killed once the
117 * request reaches the dispatch list. The ipi_list is only used
118 * to queue the request for softirq completion, which is long
119 * after the request has been unhashed (and even removed from
120 * the dispatch list).
123 struct hlist_node hash
; /* merge hash */
124 struct list_head ipi_list
;
128 * The rb_node is only used inside the io scheduler, requests
129 * are pruned when moved to the dispatch queue. So let the
130 * completion_data share space with the rb_node.
133 struct rb_node rb_node
; /* sort/lookup */
134 void *completion_data
;
138 * Three pointers are available for the IO schedulers, if they need
139 * more they have to dynamically allocate it. Flush requests are
140 * never put on the IO scheduler. So let the flush fields share
141 * space with the elevator data.
151 struct list_head list
;
152 rq_end_io_fn
*saved_end_io
;
156 struct gendisk
*rq_disk
;
157 struct hd_struct
*part
;
158 unsigned long start_time
;
159 #ifdef CONFIG_BLK_CGROUP
160 struct request_list
*rl
; /* rl this rq is alloced from */
161 unsigned long long start_time_ns
;
162 unsigned long long io_start_time_ns
; /* when passed to hardware */
164 /* Number of scatter-gather DMA addr+len pairs after
165 * physical address coalescing is performed.
167 unsigned short nr_phys_segments
;
168 #if defined(CONFIG_BLK_DEV_INTEGRITY)
169 unsigned short nr_integrity_segments
;
172 unsigned short ioprio
;
174 void *special
; /* opaque pointer available for LLD use */
180 * when request is used as a packet command carrier
182 unsigned char __cmd
[BLK_MAX_CDB
];
184 unsigned short cmd_len
;
186 unsigned int extra_len
; /* length of alignment and padding */
187 unsigned int sense_len
;
188 unsigned int resid_len
; /* residual count */
191 unsigned long deadline
;
192 struct list_head timeout_list
;
193 unsigned int timeout
;
197 * completion callback.
199 rq_end_io_fn
*end_io
;
203 struct request
*next_rq
;
206 static inline unsigned short req_get_ioprio(struct request
*req
)
212 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
213 * requests. Some step values could eventually be made generic.
215 struct request_pm_state
217 /* PM state machine step value, currently driver specific */
219 /* requested PM state value (S1, S2, S3, S4, ...) */
221 void* data
; /* for driver use */
224 #include <linux/elevator.h>
226 struct blk_queue_ctx
;
228 typedef void (request_fn_proc
) (struct request_queue
*q
);
229 typedef void (make_request_fn
) (struct request_queue
*q
, struct bio
*bio
);
230 typedef int (prep_rq_fn
) (struct request_queue
*, struct request
*);
231 typedef void (unprep_rq_fn
) (struct request_queue
*, struct request
*);
234 struct bvec_merge_data
{
235 struct block_device
*bi_bdev
;
240 typedef int (merge_bvec_fn
) (struct request_queue
*, struct bvec_merge_data
*,
242 typedef void (softirq_done_fn
)(struct request
*);
243 typedef int (dma_drain_needed_fn
)(struct request
*);
244 typedef int (lld_busy_fn
) (struct request_queue
*q
);
245 typedef int (bsg_job_fn
) (struct bsg_job
*);
247 enum blk_eh_timer_return
{
253 typedef enum blk_eh_timer_return (rq_timed_out_fn
)(struct request
*);
255 enum blk_queue_state
{
260 struct blk_queue_tag
{
261 struct request
**tag_index
; /* map of busy tags */
262 unsigned long *tag_map
; /* bit map of free/busy tags */
263 int busy
; /* current depth */
264 int max_depth
; /* what we will send to device */
265 int real_max_depth
; /* what the array can hold */
266 atomic_t refcnt
; /* map can be shared */
267 int alloc_policy
; /* tag allocation policy */
268 int next_tag
; /* next tag */
270 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
271 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
273 #define BLK_SCSI_MAX_CMDS (256)
274 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
276 struct queue_limits
{
277 unsigned long bounce_pfn
;
278 unsigned long seg_boundary_mask
;
280 unsigned int max_hw_sectors
;
281 unsigned int chunk_sectors
;
282 unsigned int max_sectors
;
283 unsigned int max_segment_size
;
284 unsigned int physical_block_size
;
285 unsigned int alignment_offset
;
288 unsigned int max_discard_sectors
;
289 unsigned int max_write_same_sectors
;
290 unsigned int discard_granularity
;
291 unsigned int discard_alignment
;
293 unsigned short logical_block_size
;
294 unsigned short max_segments
;
295 unsigned short max_integrity_segments
;
297 unsigned char misaligned
;
298 unsigned char discard_misaligned
;
299 unsigned char cluster
;
300 unsigned char discard_zeroes_data
;
301 unsigned char raid_partial_stripes_expensive
;
304 struct request_queue
{
306 * Together with queue_head for cacheline sharing
308 struct list_head queue_head
;
309 struct request
*last_merge
;
310 struct elevator_queue
*elevator
;
311 int nr_rqs
[2]; /* # allocated [a]sync rqs */
312 int nr_rqs_elvpriv
; /* # allocated rqs w/ elvpriv */
315 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
316 * is used, root blkg allocates from @q->root_rl and all other
317 * blkgs from their own blkg->rl. Which one to use should be
318 * determined using bio_request_list().
320 struct request_list root_rl
;
322 request_fn_proc
*request_fn
;
323 make_request_fn
*make_request_fn
;
324 prep_rq_fn
*prep_rq_fn
;
325 unprep_rq_fn
*unprep_rq_fn
;
326 merge_bvec_fn
*merge_bvec_fn
;
327 softirq_done_fn
*softirq_done_fn
;
328 rq_timed_out_fn
*rq_timed_out_fn
;
329 dma_drain_needed_fn
*dma_drain_needed
;
330 lld_busy_fn
*lld_busy_fn
;
332 struct blk_mq_ops
*mq_ops
;
334 unsigned int *mq_map
;
337 struct blk_mq_ctx __percpu
*queue_ctx
;
338 unsigned int nr_queues
;
340 /* hw dispatch queues */
341 struct blk_mq_hw_ctx
**queue_hw_ctx
;
342 unsigned int nr_hw_queues
;
345 * Dispatch queue sorting
348 struct request
*boundary_rq
;
351 * Delayed queue handling
353 struct delayed_work delay_work
;
355 struct backing_dev_info backing_dev_info
;
358 * The queue owner gets to use this for whatever they like.
359 * ll_rw_blk doesn't touch it.
364 * various queue flags, see QUEUE_* below
366 unsigned long queue_flags
;
369 * ida allocated id for this queue. Used to index queues from
375 * queue needs bounce pages for pages above this limit
380 * protects queue structures from reentrancy. ->__queue_lock should
381 * _never_ be used directly, it is queue private. always use
384 spinlock_t __queue_lock
;
385 spinlock_t
*queue_lock
;
395 struct kobject mq_kobj
;
400 unsigned int nr_pending
;
406 unsigned long nr_requests
; /* Max # of requests */
407 unsigned int nr_congestion_on
;
408 unsigned int nr_congestion_off
;
409 unsigned int nr_batching
;
411 unsigned int dma_drain_size
;
412 void *dma_drain_buffer
;
413 unsigned int dma_pad_mask
;
414 unsigned int dma_alignment
;
416 struct blk_queue_tag
*queue_tags
;
417 struct list_head tag_busy_list
;
419 unsigned int nr_sorted
;
420 unsigned int in_flight
[2];
422 * Number of active block driver functions for which blk_drain_queue()
423 * must wait. Must be incremented around functions that unlock the
424 * queue_lock internally, e.g. scsi_request_fn().
426 unsigned int request_fn_active
;
428 unsigned int rq_timeout
;
429 struct timer_list timeout
;
430 struct list_head timeout_list
;
432 struct list_head icq_list
;
433 #ifdef CONFIG_BLK_CGROUP
434 DECLARE_BITMAP (blkcg_pols
, BLKCG_MAX_POLS
);
435 struct blkcg_gq
*root_blkg
;
436 struct list_head blkg_list
;
439 struct queue_limits limits
;
444 unsigned int sg_timeout
;
445 unsigned int sg_reserved_size
;
447 #ifdef CONFIG_BLK_DEV_IO_TRACE
448 struct blk_trace
*blk_trace
;
451 * for flush operations
453 unsigned int flush_flags
;
454 unsigned int flush_not_queueable
:1;
455 struct blk_flush_queue
*fq
;
457 struct list_head requeue_list
;
458 spinlock_t requeue_lock
;
459 struct work_struct requeue_work
;
461 struct mutex sysfs_lock
;
466 #if defined(CONFIG_BLK_DEV_BSG)
467 bsg_job_fn
*bsg_job_fn
;
469 struct bsg_class_device bsg_dev
;
472 #ifdef CONFIG_BLK_DEV_THROTTLING
474 struct throtl_data
*td
;
476 struct rcu_head rcu_head
;
477 wait_queue_head_t mq_freeze_wq
;
478 struct percpu_ref mq_usage_counter
;
479 struct list_head all_q_node
;
481 struct blk_mq_tag_set
*tag_set
;
482 struct list_head tag_set_list
;
485 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
486 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
487 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
488 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
489 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
490 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
491 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
492 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
493 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
494 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
495 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
496 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
497 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
498 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
499 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
500 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
501 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
502 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
503 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
504 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
505 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
506 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
507 #define QUEUE_FLAG_SG_GAPS 22 /* queue doesn't support SG gaps */
509 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
510 (1 << QUEUE_FLAG_STACKABLE) | \
511 (1 << QUEUE_FLAG_SAME_COMP) | \
512 (1 << QUEUE_FLAG_ADD_RANDOM))
514 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
515 (1 << QUEUE_FLAG_STACKABLE) | \
516 (1 << QUEUE_FLAG_SAME_COMP))
518 static inline void queue_lockdep_assert_held(struct request_queue
*q
)
521 lockdep_assert_held(q
->queue_lock
);
524 static inline void queue_flag_set_unlocked(unsigned int flag
,
525 struct request_queue
*q
)
527 __set_bit(flag
, &q
->queue_flags
);
530 static inline int queue_flag_test_and_clear(unsigned int flag
,
531 struct request_queue
*q
)
533 queue_lockdep_assert_held(q
);
535 if (test_bit(flag
, &q
->queue_flags
)) {
536 __clear_bit(flag
, &q
->queue_flags
);
543 static inline int queue_flag_test_and_set(unsigned int flag
,
544 struct request_queue
*q
)
546 queue_lockdep_assert_held(q
);
548 if (!test_bit(flag
, &q
->queue_flags
)) {
549 __set_bit(flag
, &q
->queue_flags
);
556 static inline void queue_flag_set(unsigned int flag
, struct request_queue
*q
)
558 queue_lockdep_assert_held(q
);
559 __set_bit(flag
, &q
->queue_flags
);
562 static inline void queue_flag_clear_unlocked(unsigned int flag
,
563 struct request_queue
*q
)
565 __clear_bit(flag
, &q
->queue_flags
);
568 static inline int queue_in_flight(struct request_queue
*q
)
570 return q
->in_flight
[0] + q
->in_flight
[1];
573 static inline void queue_flag_clear(unsigned int flag
, struct request_queue
*q
)
575 queue_lockdep_assert_held(q
);
576 __clear_bit(flag
, &q
->queue_flags
);
579 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
580 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
581 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
582 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
583 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
584 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
585 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
586 #define blk_queue_noxmerges(q) \
587 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
588 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
589 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
590 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
591 #define blk_queue_stackable(q) \
592 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
593 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
594 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
595 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
597 #define blk_noretry_request(rq) \
598 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
599 REQ_FAILFAST_DRIVER))
601 #define blk_account_rq(rq) \
602 (((rq)->cmd_flags & REQ_STARTED) && \
603 ((rq)->cmd_type == REQ_TYPE_FS))
605 #define blk_pm_request(rq) \
606 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
607 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
609 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
610 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
611 /* rq->queuelist of dequeued request must be list_empty() */
612 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
614 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
616 #define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
619 * Driver can handle struct request, if it either has an old style
620 * request_fn defined, or is blk-mq based.
622 static inline bool queue_is_rq_based(struct request_queue
*q
)
624 return q
->request_fn
|| q
->mq_ops
;
627 static inline unsigned int blk_queue_cluster(struct request_queue
*q
)
629 return q
->limits
.cluster
;
633 * We regard a request as sync, if either a read or a sync write
635 static inline bool rw_is_sync(unsigned int rw_flags
)
637 return !(rw_flags
& REQ_WRITE
) || (rw_flags
& REQ_SYNC
);
640 static inline bool rq_is_sync(struct request
*rq
)
642 return rw_is_sync(rq
->cmd_flags
);
645 static inline bool blk_rl_full(struct request_list
*rl
, bool sync
)
647 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
649 return rl
->flags
& flag
;
652 static inline void blk_set_rl_full(struct request_list
*rl
, bool sync
)
654 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
659 static inline void blk_clear_rl_full(struct request_list
*rl
, bool sync
)
661 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
666 static inline bool rq_mergeable(struct request
*rq
)
668 if (rq
->cmd_type
!= REQ_TYPE_FS
)
671 if (rq
->cmd_flags
& REQ_NOMERGE_FLAGS
)
677 static inline bool blk_check_merge_flags(unsigned int flags1
,
680 if ((flags1
& REQ_DISCARD
) != (flags2
& REQ_DISCARD
))
683 if ((flags1
& REQ_SECURE
) != (flags2
& REQ_SECURE
))
686 if ((flags1
& REQ_WRITE_SAME
) != (flags2
& REQ_WRITE_SAME
))
692 static inline bool blk_write_same_mergeable(struct bio
*a
, struct bio
*b
)
694 if (bio_data(a
) == bio_data(b
))
701 * q->prep_rq_fn return values
703 #define BLKPREP_OK 0 /* serve it */
704 #define BLKPREP_KILL 1 /* fatal error, kill */
705 #define BLKPREP_DEFER 2 /* leave on queue */
707 extern unsigned long blk_max_low_pfn
, blk_max_pfn
;
710 * standard bounce addresses:
712 * BLK_BOUNCE_HIGH : bounce all highmem pages
713 * BLK_BOUNCE_ANY : don't bounce anything
714 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
717 #if BITS_PER_LONG == 32
718 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
720 #define BLK_BOUNCE_HIGH -1ULL
722 #define BLK_BOUNCE_ANY (-1ULL)
723 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
726 * default timeout for SG_IO if none specified
728 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
729 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
732 extern int init_emergency_isa_pool(void);
733 extern void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
);
735 static inline int init_emergency_isa_pool(void)
739 static inline void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
)
742 #endif /* CONFIG_MMU */
748 unsigned long offset
;
753 struct req_iterator
{
754 struct bvec_iter iter
;
758 /* This should not be used directly - use rq_for_each_segment */
759 #define for_each_bio(_bio) \
760 for (; _bio; _bio = _bio->bi_next)
761 #define __rq_for_each_bio(_bio, rq) \
763 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
765 #define rq_for_each_segment(bvl, _rq, _iter) \
766 __rq_for_each_bio(_iter.bio, _rq) \
767 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
769 #define rq_iter_last(bvec, _iter) \
770 (_iter.bio->bi_next == NULL && \
771 bio_iter_last(bvec, _iter.iter))
773 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
774 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
776 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
777 extern void rq_flush_dcache_pages(struct request
*rq
);
779 static inline void rq_flush_dcache_pages(struct request
*rq
)
784 extern int blk_register_queue(struct gendisk
*disk
);
785 extern void blk_unregister_queue(struct gendisk
*disk
);
786 extern void generic_make_request(struct bio
*bio
);
787 extern void blk_rq_init(struct request_queue
*q
, struct request
*rq
);
788 extern void blk_put_request(struct request
*);
789 extern void __blk_put_request(struct request_queue
*, struct request
*);
790 extern struct request
*blk_get_request(struct request_queue
*, int, gfp_t
);
791 extern struct request
*blk_make_request(struct request_queue
*, struct bio
*,
793 extern void blk_rq_set_block_pc(struct request
*);
794 extern void blk_requeue_request(struct request_queue
*, struct request
*);
795 extern void blk_add_request_payload(struct request
*rq
, struct page
*page
,
797 extern int blk_rq_check_limits(struct request_queue
*q
, struct request
*rq
);
798 extern int blk_lld_busy(struct request_queue
*q
);
799 extern int blk_rq_prep_clone(struct request
*rq
, struct request
*rq_src
,
800 struct bio_set
*bs
, gfp_t gfp_mask
,
801 int (*bio_ctr
)(struct bio
*, struct bio
*, void *),
803 extern void blk_rq_unprep_clone(struct request
*rq
);
804 extern int blk_insert_cloned_request(struct request_queue
*q
,
806 extern void blk_delay_queue(struct request_queue
*, unsigned long);
807 extern void blk_recount_segments(struct request_queue
*, struct bio
*);
808 extern int scsi_verify_blk_ioctl(struct block_device
*, unsigned int);
809 extern int scsi_cmd_blk_ioctl(struct block_device
*, fmode_t
,
810 unsigned int, void __user
*);
811 extern int scsi_cmd_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
812 unsigned int, void __user
*);
813 extern int sg_scsi_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
814 struct scsi_ioctl_command __user
*);
816 extern void blk_queue_bio(struct request_queue
*q
, struct bio
*bio
);
819 * A queue has just exitted congestion. Note this in the global counter of
820 * congested queues, and wake up anyone who was waiting for requests to be
823 static inline void blk_clear_queue_congested(struct request_queue
*q
, int sync
)
825 clear_bdi_congested(&q
->backing_dev_info
, sync
);
829 * A queue has just entered congestion. Flag that in the queue's VM-visible
830 * state flags and increment the global gounter of congested queues.
832 static inline void blk_set_queue_congested(struct request_queue
*q
, int sync
)
834 set_bdi_congested(&q
->backing_dev_info
, sync
);
837 extern void blk_start_queue(struct request_queue
*q
);
838 extern void blk_stop_queue(struct request_queue
*q
);
839 extern void blk_sync_queue(struct request_queue
*q
);
840 extern void __blk_stop_queue(struct request_queue
*q
);
841 extern void __blk_run_queue(struct request_queue
*q
);
842 extern void blk_run_queue(struct request_queue
*);
843 extern void blk_run_queue_async(struct request_queue
*q
);
844 extern int blk_rq_map_user(struct request_queue
*, struct request
*,
845 struct rq_map_data
*, void __user
*, unsigned long,
847 extern int blk_rq_unmap_user(struct bio
*);
848 extern int blk_rq_map_kern(struct request_queue
*, struct request
*, void *, unsigned int, gfp_t
);
849 extern int blk_rq_map_user_iov(struct request_queue
*, struct request
*,
850 struct rq_map_data
*, const struct iov_iter
*,
852 extern int blk_execute_rq(struct request_queue
*, struct gendisk
*,
853 struct request
*, int);
854 extern void blk_execute_rq_nowait(struct request_queue
*, struct gendisk
*,
855 struct request
*, int, rq_end_io_fn
*);
857 static inline struct request_queue
*bdev_get_queue(struct block_device
*bdev
)
859 return bdev
->bd_disk
->queue
; /* this is never NULL */
863 * blk_rq_pos() : the current sector
864 * blk_rq_bytes() : bytes left in the entire request
865 * blk_rq_cur_bytes() : bytes left in the current segment
866 * blk_rq_err_bytes() : bytes left till the next error boundary
867 * blk_rq_sectors() : sectors left in the entire request
868 * blk_rq_cur_sectors() : sectors left in the current segment
870 static inline sector_t
blk_rq_pos(const struct request
*rq
)
875 static inline unsigned int blk_rq_bytes(const struct request
*rq
)
877 return rq
->__data_len
;
880 static inline int blk_rq_cur_bytes(const struct request
*rq
)
882 return rq
->bio
? bio_cur_bytes(rq
->bio
) : 0;
885 extern unsigned int blk_rq_err_bytes(const struct request
*rq
);
887 static inline unsigned int blk_rq_sectors(const struct request
*rq
)
889 return blk_rq_bytes(rq
) >> 9;
892 static inline unsigned int blk_rq_cur_sectors(const struct request
*rq
)
894 return blk_rq_cur_bytes(rq
) >> 9;
897 static inline unsigned int blk_queue_get_max_sectors(struct request_queue
*q
,
898 unsigned int cmd_flags
)
900 if (unlikely(cmd_flags
& REQ_DISCARD
))
901 return min(q
->limits
.max_discard_sectors
, UINT_MAX
>> 9);
903 if (unlikely(cmd_flags
& REQ_WRITE_SAME
))
904 return q
->limits
.max_write_same_sectors
;
906 return q
->limits
.max_sectors
;
910 * Return maximum size of a request at given offset. Only valid for
911 * file system requests.
913 static inline unsigned int blk_max_size_offset(struct request_queue
*q
,
916 if (!q
->limits
.chunk_sectors
)
917 return q
->limits
.max_sectors
;
919 return q
->limits
.chunk_sectors
-
920 (offset
& (q
->limits
.chunk_sectors
- 1));
923 static inline unsigned int blk_rq_get_max_sectors(struct request
*rq
)
925 struct request_queue
*q
= rq
->q
;
927 if (unlikely(rq
->cmd_type
== REQ_TYPE_BLOCK_PC
))
928 return q
->limits
.max_hw_sectors
;
930 if (!q
->limits
.chunk_sectors
)
931 return blk_queue_get_max_sectors(q
, rq
->cmd_flags
);
933 return min(blk_max_size_offset(q
, blk_rq_pos(rq
)),
934 blk_queue_get_max_sectors(q
, rq
->cmd_flags
));
937 static inline unsigned int blk_rq_count_bios(struct request
*rq
)
939 unsigned int nr_bios
= 0;
942 __rq_for_each_bio(bio
, rq
)
949 * Request issue related functions.
951 extern struct request
*blk_peek_request(struct request_queue
*q
);
952 extern void blk_start_request(struct request
*rq
);
953 extern struct request
*blk_fetch_request(struct request_queue
*q
);
956 * Request completion related functions.
958 * blk_update_request() completes given number of bytes and updates
959 * the request without completing it.
961 * blk_end_request() and friends. __blk_end_request() must be called
962 * with the request queue spinlock acquired.
964 * Several drivers define their own end_request and call
965 * blk_end_request() for parts of the original function.
966 * This prevents code duplication in drivers.
968 extern bool blk_update_request(struct request
*rq
, int error
,
969 unsigned int nr_bytes
);
970 extern void blk_finish_request(struct request
*rq
, int error
);
971 extern bool blk_end_request(struct request
*rq
, int error
,
972 unsigned int nr_bytes
);
973 extern void blk_end_request_all(struct request
*rq
, int error
);
974 extern bool blk_end_request_cur(struct request
*rq
, int error
);
975 extern bool blk_end_request_err(struct request
*rq
, int error
);
976 extern bool __blk_end_request(struct request
*rq
, int error
,
977 unsigned int nr_bytes
);
978 extern void __blk_end_request_all(struct request
*rq
, int error
);
979 extern bool __blk_end_request_cur(struct request
*rq
, int error
);
980 extern bool __blk_end_request_err(struct request
*rq
, int error
);
982 extern void blk_complete_request(struct request
*);
983 extern void __blk_complete_request(struct request
*);
984 extern void blk_abort_request(struct request
*);
985 extern void blk_unprep_request(struct request
*);
988 * Access functions for manipulating queue properties
990 extern struct request_queue
*blk_init_queue_node(request_fn_proc
*rfn
,
991 spinlock_t
*lock
, int node_id
);
992 extern struct request_queue
*blk_init_queue(request_fn_proc
*, spinlock_t
*);
993 extern struct request_queue
*blk_init_allocated_queue(struct request_queue
*,
994 request_fn_proc
*, spinlock_t
*);
995 extern void blk_cleanup_queue(struct request_queue
*);
996 extern void blk_queue_make_request(struct request_queue
*, make_request_fn
*);
997 extern void blk_queue_bounce_limit(struct request_queue
*, u64
);
998 extern void blk_limits_max_hw_sectors(struct queue_limits
*, unsigned int);
999 extern void blk_queue_max_hw_sectors(struct request_queue
*, unsigned int);
1000 extern void blk_queue_chunk_sectors(struct request_queue
*, unsigned int);
1001 extern void blk_queue_max_segments(struct request_queue
*, unsigned short);
1002 extern void blk_queue_max_segment_size(struct request_queue
*, unsigned int);
1003 extern void blk_queue_max_discard_sectors(struct request_queue
*q
,
1004 unsigned int max_discard_sectors
);
1005 extern void blk_queue_max_write_same_sectors(struct request_queue
*q
,
1006 unsigned int max_write_same_sectors
);
1007 extern void blk_queue_logical_block_size(struct request_queue
*, unsigned short);
1008 extern void blk_queue_physical_block_size(struct request_queue
*, unsigned int);
1009 extern void blk_queue_alignment_offset(struct request_queue
*q
,
1010 unsigned int alignment
);
1011 extern void blk_limits_io_min(struct queue_limits
*limits
, unsigned int min
);
1012 extern void blk_queue_io_min(struct request_queue
*q
, unsigned int min
);
1013 extern void blk_limits_io_opt(struct queue_limits
*limits
, unsigned int opt
);
1014 extern void blk_queue_io_opt(struct request_queue
*q
, unsigned int opt
);
1015 extern void blk_set_default_limits(struct queue_limits
*lim
);
1016 extern void blk_set_stacking_limits(struct queue_limits
*lim
);
1017 extern int blk_stack_limits(struct queue_limits
*t
, struct queue_limits
*b
,
1019 extern int bdev_stack_limits(struct queue_limits
*t
, struct block_device
*bdev
,
1021 extern void disk_stack_limits(struct gendisk
*disk
, struct block_device
*bdev
,
1023 extern void blk_queue_stack_limits(struct request_queue
*t
, struct request_queue
*b
);
1024 extern void blk_queue_dma_pad(struct request_queue
*, unsigned int);
1025 extern void blk_queue_update_dma_pad(struct request_queue
*, unsigned int);
1026 extern int blk_queue_dma_drain(struct request_queue
*q
,
1027 dma_drain_needed_fn
*dma_drain_needed
,
1028 void *buf
, unsigned int size
);
1029 extern void blk_queue_lld_busy(struct request_queue
*q
, lld_busy_fn
*fn
);
1030 extern void blk_queue_segment_boundary(struct request_queue
*, unsigned long);
1031 extern void blk_queue_prep_rq(struct request_queue
*, prep_rq_fn
*pfn
);
1032 extern void blk_queue_unprep_rq(struct request_queue
*, unprep_rq_fn
*ufn
);
1033 extern void blk_queue_merge_bvec(struct request_queue
*, merge_bvec_fn
*);
1034 extern void blk_queue_dma_alignment(struct request_queue
*, int);
1035 extern void blk_queue_update_dma_alignment(struct request_queue
*, int);
1036 extern void blk_queue_softirq_done(struct request_queue
*, softirq_done_fn
*);
1037 extern void blk_queue_rq_timed_out(struct request_queue
*, rq_timed_out_fn
*);
1038 extern void blk_queue_rq_timeout(struct request_queue
*, unsigned int);
1039 extern void blk_queue_flush(struct request_queue
*q
, unsigned int flush
);
1040 extern void blk_queue_flush_queueable(struct request_queue
*q
, bool queueable
);
1041 extern struct backing_dev_info
*blk_get_backing_dev_info(struct block_device
*bdev
);
1043 extern int blk_rq_map_sg(struct request_queue
*, struct request
*, struct scatterlist
*);
1044 extern void blk_dump_rq_flags(struct request
*, char *);
1045 extern long nr_blockdev_pages(void);
1047 bool __must_check
blk_get_queue(struct request_queue
*);
1048 struct request_queue
*blk_alloc_queue(gfp_t
);
1049 struct request_queue
*blk_alloc_queue_node(gfp_t
, int);
1050 extern void blk_put_queue(struct request_queue
*);
1053 * block layer runtime pm functions
1056 extern void blk_pm_runtime_init(struct request_queue
*q
, struct device
*dev
);
1057 extern int blk_pre_runtime_suspend(struct request_queue
*q
);
1058 extern void blk_post_runtime_suspend(struct request_queue
*q
, int err
);
1059 extern void blk_pre_runtime_resume(struct request_queue
*q
);
1060 extern void blk_post_runtime_resume(struct request_queue
*q
, int err
);
1062 static inline void blk_pm_runtime_init(struct request_queue
*q
,
1063 struct device
*dev
) {}
1064 static inline int blk_pre_runtime_suspend(struct request_queue
*q
)
1068 static inline void blk_post_runtime_suspend(struct request_queue
*q
, int err
) {}
1069 static inline void blk_pre_runtime_resume(struct request_queue
*q
) {}
1070 static inline void blk_post_runtime_resume(struct request_queue
*q
, int err
) {}
1074 * blk_plug permits building a queue of related requests by holding the I/O
1075 * fragments for a short period. This allows merging of sequential requests
1076 * into single larger request. As the requests are moved from a per-task list to
1077 * the device's request_queue in a batch, this results in improved scalability
1078 * as the lock contention for request_queue lock is reduced.
1080 * It is ok not to disable preemption when adding the request to the plug list
1081 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1082 * the plug list when the task sleeps by itself. For details, please see
1083 * schedule() where blk_schedule_flush_plug() is called.
1086 struct list_head list
; /* requests */
1087 struct list_head mq_list
; /* blk-mq requests */
1088 struct list_head cb_list
; /* md requires an unplug callback */
1090 #define BLK_MAX_REQUEST_COUNT 16
1093 typedef void (*blk_plug_cb_fn
)(struct blk_plug_cb
*, bool);
1094 struct blk_plug_cb
{
1095 struct list_head list
;
1096 blk_plug_cb_fn callback
;
1099 extern struct blk_plug_cb
*blk_check_plugged(blk_plug_cb_fn unplug
,
1100 void *data
, int size
);
1101 extern void blk_start_plug(struct blk_plug
*);
1102 extern void blk_finish_plug(struct blk_plug
*);
1103 extern void blk_flush_plug_list(struct blk_plug
*, bool);
1105 static inline void blk_flush_plug(struct task_struct
*tsk
)
1107 struct blk_plug
*plug
= tsk
->plug
;
1110 blk_flush_plug_list(plug
, false);
1113 static inline void blk_schedule_flush_plug(struct task_struct
*tsk
)
1115 struct blk_plug
*plug
= tsk
->plug
;
1118 blk_flush_plug_list(plug
, true);
1121 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1123 struct blk_plug
*plug
= tsk
->plug
;
1126 (!list_empty(&plug
->list
) ||
1127 !list_empty(&plug
->mq_list
) ||
1128 !list_empty(&plug
->cb_list
));
1134 extern int blk_queue_start_tag(struct request_queue
*, struct request
*);
1135 extern struct request
*blk_queue_find_tag(struct request_queue
*, int);
1136 extern void blk_queue_end_tag(struct request_queue
*, struct request
*);
1137 extern int blk_queue_init_tags(struct request_queue
*, int, struct blk_queue_tag
*, int);
1138 extern void blk_queue_free_tags(struct request_queue
*);
1139 extern int blk_queue_resize_tags(struct request_queue
*, int);
1140 extern void blk_queue_invalidate_tags(struct request_queue
*);
1141 extern struct blk_queue_tag
*blk_init_tags(int, int);
1142 extern void blk_free_tags(struct blk_queue_tag
*);
1144 static inline struct request
*blk_map_queue_find_tag(struct blk_queue_tag
*bqt
,
1147 if (unlikely(bqt
== NULL
|| tag
>= bqt
->real_max_depth
))
1149 return bqt
->tag_index
[tag
];
1152 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1154 extern int blkdev_issue_flush(struct block_device
*, gfp_t
, sector_t
*);
1155 extern int blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
1156 sector_t nr_sects
, gfp_t gfp_mask
, unsigned long flags
);
1157 extern int blkdev_issue_write_same(struct block_device
*bdev
, sector_t sector
,
1158 sector_t nr_sects
, gfp_t gfp_mask
, struct page
*page
);
1159 extern int blkdev_issue_zeroout(struct block_device
*bdev
, sector_t sector
,
1160 sector_t nr_sects
, gfp_t gfp_mask
, bool discard
);
1161 static inline int sb_issue_discard(struct super_block
*sb
, sector_t block
,
1162 sector_t nr_blocks
, gfp_t gfp_mask
, unsigned long flags
)
1164 return blkdev_issue_discard(sb
->s_bdev
, block
<< (sb
->s_blocksize_bits
- 9),
1165 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1168 static inline int sb_issue_zeroout(struct super_block
*sb
, sector_t block
,
1169 sector_t nr_blocks
, gfp_t gfp_mask
)
1171 return blkdev_issue_zeroout(sb
->s_bdev
,
1172 block
<< (sb
->s_blocksize_bits
- 9),
1173 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1177 extern int blk_verify_command(unsigned char *cmd
, fmode_t has_write_perm
);
1179 enum blk_default_limits
{
1180 BLK_MAX_SEGMENTS
= 128,
1181 BLK_SAFE_MAX_SECTORS
= 255,
1182 BLK_MAX_SEGMENT_SIZE
= 65536,
1183 BLK_SEG_BOUNDARY_MASK
= 0xFFFFFFFFUL
,
1186 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1188 static inline unsigned long queue_bounce_pfn(struct request_queue
*q
)
1190 return q
->limits
.bounce_pfn
;
1193 static inline unsigned long queue_segment_boundary(struct request_queue
*q
)
1195 return q
->limits
.seg_boundary_mask
;
1198 static inline unsigned int queue_max_sectors(struct request_queue
*q
)
1200 return q
->limits
.max_sectors
;
1203 static inline unsigned int queue_max_hw_sectors(struct request_queue
*q
)
1205 return q
->limits
.max_hw_sectors
;
1208 static inline unsigned short queue_max_segments(struct request_queue
*q
)
1210 return q
->limits
.max_segments
;
1213 static inline unsigned int queue_max_segment_size(struct request_queue
*q
)
1215 return q
->limits
.max_segment_size
;
1218 static inline unsigned short queue_logical_block_size(struct request_queue
*q
)
1222 if (q
&& q
->limits
.logical_block_size
)
1223 retval
= q
->limits
.logical_block_size
;
1228 static inline unsigned short bdev_logical_block_size(struct block_device
*bdev
)
1230 return queue_logical_block_size(bdev_get_queue(bdev
));
1233 static inline unsigned int queue_physical_block_size(struct request_queue
*q
)
1235 return q
->limits
.physical_block_size
;
1238 static inline unsigned int bdev_physical_block_size(struct block_device
*bdev
)
1240 return queue_physical_block_size(bdev_get_queue(bdev
));
1243 static inline unsigned int queue_io_min(struct request_queue
*q
)
1245 return q
->limits
.io_min
;
1248 static inline int bdev_io_min(struct block_device
*bdev
)
1250 return queue_io_min(bdev_get_queue(bdev
));
1253 static inline unsigned int queue_io_opt(struct request_queue
*q
)
1255 return q
->limits
.io_opt
;
1258 static inline int bdev_io_opt(struct block_device
*bdev
)
1260 return queue_io_opt(bdev_get_queue(bdev
));
1263 static inline int queue_alignment_offset(struct request_queue
*q
)
1265 if (q
->limits
.misaligned
)
1268 return q
->limits
.alignment_offset
;
1271 static inline int queue_limit_alignment_offset(struct queue_limits
*lim
, sector_t sector
)
1273 unsigned int granularity
= max(lim
->physical_block_size
, lim
->io_min
);
1274 unsigned int alignment
= sector_div(sector
, granularity
>> 9) << 9;
1276 return (granularity
+ lim
->alignment_offset
- alignment
) % granularity
;
1279 static inline int bdev_alignment_offset(struct block_device
*bdev
)
1281 struct request_queue
*q
= bdev_get_queue(bdev
);
1283 if (q
->limits
.misaligned
)
1286 if (bdev
!= bdev
->bd_contains
)
1287 return bdev
->bd_part
->alignment_offset
;
1289 return q
->limits
.alignment_offset
;
1292 static inline int queue_discard_alignment(struct request_queue
*q
)
1294 if (q
->limits
.discard_misaligned
)
1297 return q
->limits
.discard_alignment
;
1300 static inline int queue_limit_discard_alignment(struct queue_limits
*lim
, sector_t sector
)
1302 unsigned int alignment
, granularity
, offset
;
1304 if (!lim
->max_discard_sectors
)
1307 /* Why are these in bytes, not sectors? */
1308 alignment
= lim
->discard_alignment
>> 9;
1309 granularity
= lim
->discard_granularity
>> 9;
1313 /* Offset of the partition start in 'granularity' sectors */
1314 offset
= sector_div(sector
, granularity
);
1316 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1317 offset
= (granularity
+ alignment
- offset
) % granularity
;
1319 /* Turn it back into bytes, gaah */
1323 static inline int bdev_discard_alignment(struct block_device
*bdev
)
1325 struct request_queue
*q
= bdev_get_queue(bdev
);
1327 if (bdev
!= bdev
->bd_contains
)
1328 return bdev
->bd_part
->discard_alignment
;
1330 return q
->limits
.discard_alignment
;
1333 static inline unsigned int queue_discard_zeroes_data(struct request_queue
*q
)
1335 if (q
->limits
.max_discard_sectors
&& q
->limits
.discard_zeroes_data
== 1)
1341 static inline unsigned int bdev_discard_zeroes_data(struct block_device
*bdev
)
1343 return queue_discard_zeroes_data(bdev_get_queue(bdev
));
1346 static inline unsigned int bdev_write_same(struct block_device
*bdev
)
1348 struct request_queue
*q
= bdev_get_queue(bdev
);
1351 return q
->limits
.max_write_same_sectors
;
1356 static inline int queue_dma_alignment(struct request_queue
*q
)
1358 return q
? q
->dma_alignment
: 511;
1361 static inline int blk_rq_aligned(struct request_queue
*q
, unsigned long addr
,
1364 unsigned int alignment
= queue_dma_alignment(q
) | q
->dma_pad_mask
;
1365 return !(addr
& alignment
) && !(len
& alignment
);
1368 /* assumes size > 256 */
1369 static inline unsigned int blksize_bits(unsigned int size
)
1371 unsigned int bits
= 8;
1375 } while (size
> 256);
1379 static inline unsigned int block_size(struct block_device
*bdev
)
1381 return bdev
->bd_block_size
;
1384 static inline bool queue_flush_queueable(struct request_queue
*q
)
1386 return !q
->flush_not_queueable
;
1389 typedef struct {struct page
*v
;} Sector
;
1391 unsigned char *read_dev_sector(struct block_device
*, sector_t
, Sector
*);
1393 static inline void put_dev_sector(Sector p
)
1395 page_cache_release(p
.v
);
1399 int kblockd_schedule_work(struct work_struct
*work
);
1400 int kblockd_schedule_delayed_work(struct delayed_work
*dwork
, unsigned long delay
);
1401 int kblockd_schedule_delayed_work_on(int cpu
, struct delayed_work
*dwork
, unsigned long delay
);
1403 #ifdef CONFIG_BLK_CGROUP
1405 * This should not be using sched_clock(). A real patch is in progress
1406 * to fix this up, until that is in place we need to disable preemption
1407 * around sched_clock() in this function and set_io_start_time_ns().
1409 static inline void set_start_time_ns(struct request
*req
)
1412 req
->start_time_ns
= sched_clock();
1416 static inline void set_io_start_time_ns(struct request
*req
)
1419 req
->io_start_time_ns
= sched_clock();
1423 static inline uint64_t rq_start_time_ns(struct request
*req
)
1425 return req
->start_time_ns
;
1428 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1430 return req
->io_start_time_ns
;
1433 static inline void set_start_time_ns(struct request
*req
) {}
1434 static inline void set_io_start_time_ns(struct request
*req
) {}
1435 static inline uint64_t rq_start_time_ns(struct request
*req
)
1439 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1445 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1446 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1447 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1448 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1450 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1452 enum blk_integrity_flags
{
1453 BLK_INTEGRITY_VERIFY
= 1 << 0,
1454 BLK_INTEGRITY_GENERATE
= 1 << 1,
1455 BLK_INTEGRITY_DEVICE_CAPABLE
= 1 << 2,
1456 BLK_INTEGRITY_IP_CHECKSUM
= 1 << 3,
1459 struct blk_integrity_iter
{
1463 unsigned int data_size
;
1464 unsigned short interval
;
1465 const char *disk_name
;
1468 typedef int (integrity_processing_fn
) (struct blk_integrity_iter
*);
1470 struct blk_integrity
{
1471 integrity_processing_fn
*generate_fn
;
1472 integrity_processing_fn
*verify_fn
;
1474 unsigned short flags
;
1475 unsigned short tuple_size
;
1476 unsigned short interval
;
1477 unsigned short tag_size
;
1481 struct kobject kobj
;
1484 extern bool blk_integrity_is_initialized(struct gendisk
*);
1485 extern int blk_integrity_register(struct gendisk
*, struct blk_integrity
*);
1486 extern void blk_integrity_unregister(struct gendisk
*);
1487 extern int blk_integrity_compare(struct gendisk
*, struct gendisk
*);
1488 extern int blk_rq_map_integrity_sg(struct request_queue
*, struct bio
*,
1489 struct scatterlist
*);
1490 extern int blk_rq_count_integrity_sg(struct request_queue
*, struct bio
*);
1491 extern bool blk_integrity_merge_rq(struct request_queue
*, struct request
*,
1493 extern bool blk_integrity_merge_bio(struct request_queue
*, struct request
*,
1497 struct blk_integrity
*bdev_get_integrity(struct block_device
*bdev
)
1499 return bdev
->bd_disk
->integrity
;
1502 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1504 return disk
->integrity
;
1507 static inline bool blk_integrity_rq(struct request
*rq
)
1509 return rq
->cmd_flags
& REQ_INTEGRITY
;
1512 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1515 q
->limits
.max_integrity_segments
= segs
;
1518 static inline unsigned short
1519 queue_max_integrity_segments(struct request_queue
*q
)
1521 return q
->limits
.max_integrity_segments
;
1524 #else /* CONFIG_BLK_DEV_INTEGRITY */
1527 struct block_device
;
1529 struct blk_integrity
;
1531 static inline int blk_integrity_rq(struct request
*rq
)
1535 static inline int blk_rq_count_integrity_sg(struct request_queue
*q
,
1540 static inline int blk_rq_map_integrity_sg(struct request_queue
*q
,
1542 struct scatterlist
*s
)
1546 static inline struct blk_integrity
*bdev_get_integrity(struct block_device
*b
)
1550 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1554 static inline int blk_integrity_compare(struct gendisk
*a
, struct gendisk
*b
)
1558 static inline int blk_integrity_register(struct gendisk
*d
,
1559 struct blk_integrity
*b
)
1563 static inline void blk_integrity_unregister(struct gendisk
*d
)
1566 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1570 static inline unsigned short queue_max_integrity_segments(struct request_queue
*q
)
1574 static inline bool blk_integrity_merge_rq(struct request_queue
*rq
,
1580 static inline bool blk_integrity_merge_bio(struct request_queue
*rq
,
1586 static inline bool blk_integrity_is_initialized(struct gendisk
*g
)
1591 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1593 struct block_device_operations
{
1594 int (*open
) (struct block_device
*, fmode_t
);
1595 void (*release
) (struct gendisk
*, fmode_t
);
1596 int (*rw_page
)(struct block_device
*, sector_t
, struct page
*, int rw
);
1597 int (*ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1598 int (*compat_ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1599 long (*direct_access
)(struct block_device
*, sector_t
,
1600 void **, unsigned long *pfn
, long size
);
1601 unsigned int (*check_events
) (struct gendisk
*disk
,
1602 unsigned int clearing
);
1603 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1604 int (*media_changed
) (struct gendisk
*);
1605 void (*unlock_native_capacity
) (struct gendisk
*);
1606 int (*revalidate_disk
) (struct gendisk
*);
1607 int (*getgeo
)(struct block_device
*, struct hd_geometry
*);
1608 /* this callback is with swap_lock and sometimes page table lock held */
1609 void (*swap_slot_free_notify
) (struct block_device
*, unsigned long);
1610 struct module
*owner
;
1613 extern int __blkdev_driver_ioctl(struct block_device
*, fmode_t
, unsigned int,
1615 extern int bdev_read_page(struct block_device
*, sector_t
, struct page
*);
1616 extern int bdev_write_page(struct block_device
*, sector_t
, struct page
*,
1617 struct writeback_control
*);
1618 extern long bdev_direct_access(struct block_device
*, sector_t
, void **addr
,
1619 unsigned long *pfn
, long size
);
1620 #else /* CONFIG_BLOCK */
1622 struct block_device
;
1625 * stubs for when the block layer is configured out
1627 #define buffer_heads_over_limit 0
1629 static inline long nr_blockdev_pages(void)
1637 static inline void blk_start_plug(struct blk_plug
*plug
)
1641 static inline void blk_finish_plug(struct blk_plug
*plug
)
1645 static inline void blk_flush_plug(struct task_struct
*task
)
1649 static inline void blk_schedule_flush_plug(struct task_struct
*task
)
1654 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1659 static inline int blkdev_issue_flush(struct block_device
*bdev
, gfp_t gfp_mask
,
1660 sector_t
*error_sector
)
1665 #endif /* CONFIG_BLOCK */