1 #ifndef _LINUX_BLKDEV_H
2 #define _LINUX_BLKDEV_H
4 #include <linux/sched.h>
8 #include <linux/major.h>
9 #include <linux/genhd.h>
10 #include <linux/list.h>
11 #include <linux/llist.h>
12 #include <linux/timer.h>
13 #include <linux/workqueue.h>
14 #include <linux/pagemap.h>
15 #include <linux/backing-dev-defs.h>
16 #include <linux/wait.h>
17 #include <linux/mempool.h>
18 #include <linux/pfn.h>
19 #include <linux/bio.h>
20 #include <linux/stringify.h>
21 #include <linux/gfp.h>
22 #include <linux/bsg.h>
23 #include <linux/smp.h>
24 #include <linux/rcupdate.h>
25 #include <linux/percpu-refcount.h>
26 #include <linux/scatterlist.h>
29 struct scsi_ioctl_command
;
32 struct elevator_queue
;
38 struct blk_flush_queue
;
41 #define BLKDEV_MIN_RQ 4
42 #define BLKDEV_MAX_RQ 128 /* Default maximum */
45 * Maximum number of blkcg policies allowed to be registered concurrently.
46 * Defined here to simplify include dependency.
48 #define BLKCG_MAX_POLS 2
51 typedef void (rq_end_io_fn
)(struct request
*, int);
53 #define BLK_RL_SYNCFULL (1U << 0)
54 #define BLK_RL_ASYNCFULL (1U << 1)
57 struct request_queue
*q
; /* the queue this rl belongs to */
58 #ifdef CONFIG_BLK_CGROUP
59 struct blkcg_gq
*blkg
; /* blkg this request pool belongs to */
62 * count[], starved[], and wait[] are indexed by
63 * BLK_RW_SYNC/BLK_RW_ASYNC
68 wait_queue_head_t wait
[2];
73 * request command types
75 enum rq_cmd_type_bits
{
76 REQ_TYPE_FS
= 1, /* fs request */
77 REQ_TYPE_BLOCK_PC
, /* scsi command */
78 REQ_TYPE_DRV_PRIV
, /* driver defined types from here */
81 #define BLK_MAX_CDB 16
84 * Try to put the fields that are referenced together in the same cacheline.
86 * If you modify this structure, make sure to update blk_rq_init() and
87 * especially blk_mq_rq_ctx_init() to take care of the added fields.
90 struct list_head queuelist
;
92 struct call_single_data csd
;
96 struct request_queue
*q
;
97 struct blk_mq_ctx
*mq_ctx
;
102 unsigned long atomic_flags
;
104 /* the following two fields are internal, NEVER access directly */
105 unsigned int __data_len
; /* total data len */
106 sector_t __sector
; /* sector cursor */
112 * The hash is used inside the scheduler, and killed once the
113 * request reaches the dispatch list. The ipi_list is only used
114 * to queue the request for softirq completion, which is long
115 * after the request has been unhashed (and even removed from
116 * the dispatch list).
119 struct hlist_node hash
; /* merge hash */
120 struct list_head ipi_list
;
124 * The rb_node is only used inside the io scheduler, requests
125 * are pruned when moved to the dispatch queue. So let the
126 * completion_data share space with the rb_node.
129 struct rb_node rb_node
; /* sort/lookup */
130 void *completion_data
;
134 * Three pointers are available for the IO schedulers, if they need
135 * more they have to dynamically allocate it. Flush requests are
136 * never put on the IO scheduler. So let the flush fields share
137 * space with the elevator data.
147 struct list_head list
;
148 rq_end_io_fn
*saved_end_io
;
152 struct gendisk
*rq_disk
;
153 struct hd_struct
*part
;
154 unsigned long start_time
;
155 #ifdef CONFIG_BLK_CGROUP
156 struct request_list
*rl
; /* rl this rq is alloced from */
157 unsigned long long start_time_ns
;
158 unsigned long long io_start_time_ns
; /* when passed to hardware */
160 /* Number of scatter-gather DMA addr+len pairs after
161 * physical address coalescing is performed.
163 unsigned short nr_phys_segments
;
164 #if defined(CONFIG_BLK_DEV_INTEGRITY)
165 unsigned short nr_integrity_segments
;
168 unsigned short ioprio
;
170 void *special
; /* opaque pointer available for LLD use */
176 * when request is used as a packet command carrier
178 unsigned char __cmd
[BLK_MAX_CDB
];
180 unsigned short cmd_len
;
182 unsigned int extra_len
; /* length of alignment and padding */
183 unsigned int sense_len
;
184 unsigned int resid_len
; /* residual count */
187 unsigned long deadline
;
188 struct list_head timeout_list
;
189 unsigned int timeout
;
193 * completion callback.
195 rq_end_io_fn
*end_io
;
199 struct request
*next_rq
;
202 #define REQ_OP_SHIFT (8 * sizeof(u64) - REQ_OP_BITS)
203 #define req_op(req) ((req)->cmd_flags >> REQ_OP_SHIFT)
205 #define req_set_op(req, op) do { \
206 WARN_ON(op >= (1 << REQ_OP_BITS)); \
207 (req)->cmd_flags &= ((1ULL << REQ_OP_SHIFT) - 1); \
208 (req)->cmd_flags |= ((u64) (op) << REQ_OP_SHIFT); \
211 #define req_set_op_attrs(req, op, flags) do { \
212 req_set_op(req, op); \
213 (req)->cmd_flags |= flags; \
216 static inline unsigned short req_get_ioprio(struct request
*req
)
221 #include <linux/elevator.h>
223 struct blk_queue_ctx
;
225 typedef void (request_fn_proc
) (struct request_queue
*q
);
226 typedef blk_qc_t (make_request_fn
) (struct request_queue
*q
, struct bio
*bio
);
227 typedef int (prep_rq_fn
) (struct request_queue
*, struct request
*);
228 typedef void (unprep_rq_fn
) (struct request_queue
*, struct request
*);
231 typedef void (softirq_done_fn
)(struct request
*);
232 typedef int (dma_drain_needed_fn
)(struct request
*);
233 typedef int (lld_busy_fn
) (struct request_queue
*q
);
234 typedef int (bsg_job_fn
) (struct bsg_job
*);
236 enum blk_eh_timer_return
{
242 typedef enum blk_eh_timer_return (rq_timed_out_fn
)(struct request
*);
244 enum blk_queue_state
{
249 struct blk_queue_tag
{
250 struct request
**tag_index
; /* map of busy tags */
251 unsigned long *tag_map
; /* bit map of free/busy tags */
252 int busy
; /* current depth */
253 int max_depth
; /* what we will send to device */
254 int real_max_depth
; /* what the array can hold */
255 atomic_t refcnt
; /* map can be shared */
256 int alloc_policy
; /* tag allocation policy */
257 int next_tag
; /* next tag */
259 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
260 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
262 #define BLK_SCSI_MAX_CMDS (256)
263 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
265 struct queue_limits
{
266 unsigned long bounce_pfn
;
267 unsigned long seg_boundary_mask
;
268 unsigned long virt_boundary_mask
;
270 unsigned int max_hw_sectors
;
271 unsigned int max_dev_sectors
;
272 unsigned int chunk_sectors
;
273 unsigned int max_sectors
;
274 unsigned int max_segment_size
;
275 unsigned int physical_block_size
;
276 unsigned int alignment_offset
;
279 unsigned int max_discard_sectors
;
280 unsigned int max_hw_discard_sectors
;
281 unsigned int max_write_same_sectors
;
282 unsigned int discard_granularity
;
283 unsigned int discard_alignment
;
285 unsigned short logical_block_size
;
286 unsigned short max_segments
;
287 unsigned short max_integrity_segments
;
289 unsigned char misaligned
;
290 unsigned char discard_misaligned
;
291 unsigned char cluster
;
292 unsigned char discard_zeroes_data
;
293 unsigned char raid_partial_stripes_expensive
;
296 struct request_queue
{
298 * Together with queue_head for cacheline sharing
300 struct list_head queue_head
;
301 struct request
*last_merge
;
302 struct elevator_queue
*elevator
;
303 int nr_rqs
[2]; /* # allocated [a]sync rqs */
304 int nr_rqs_elvpriv
; /* # allocated rqs w/ elvpriv */
307 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
308 * is used, root blkg allocates from @q->root_rl and all other
309 * blkgs from their own blkg->rl. Which one to use should be
310 * determined using bio_request_list().
312 struct request_list root_rl
;
314 request_fn_proc
*request_fn
;
315 make_request_fn
*make_request_fn
;
316 prep_rq_fn
*prep_rq_fn
;
317 unprep_rq_fn
*unprep_rq_fn
;
318 softirq_done_fn
*softirq_done_fn
;
319 rq_timed_out_fn
*rq_timed_out_fn
;
320 dma_drain_needed_fn
*dma_drain_needed
;
321 lld_busy_fn
*lld_busy_fn
;
323 struct blk_mq_ops
*mq_ops
;
325 unsigned int *mq_map
;
328 struct blk_mq_ctx __percpu
*queue_ctx
;
329 unsigned int nr_queues
;
331 /* hw dispatch queues */
332 struct blk_mq_hw_ctx
**queue_hw_ctx
;
333 unsigned int nr_hw_queues
;
336 * Dispatch queue sorting
339 struct request
*boundary_rq
;
342 * Delayed queue handling
344 struct delayed_work delay_work
;
346 struct backing_dev_info backing_dev_info
;
349 * The queue owner gets to use this for whatever they like.
350 * ll_rw_blk doesn't touch it.
355 * various queue flags, see QUEUE_* below
357 unsigned long queue_flags
;
360 * ida allocated id for this queue. Used to index queues from
366 * queue needs bounce pages for pages above this limit
371 * protects queue structures from reentrancy. ->__queue_lock should
372 * _never_ be used directly, it is queue private. always use
375 spinlock_t __queue_lock
;
376 spinlock_t
*queue_lock
;
386 struct kobject mq_kobj
;
388 #ifdef CONFIG_BLK_DEV_INTEGRITY
389 struct blk_integrity integrity
;
390 #endif /* CONFIG_BLK_DEV_INTEGRITY */
395 unsigned int nr_pending
;
401 unsigned long nr_requests
; /* Max # of requests */
402 unsigned int nr_congestion_on
;
403 unsigned int nr_congestion_off
;
404 unsigned int nr_batching
;
406 unsigned int dma_drain_size
;
407 void *dma_drain_buffer
;
408 unsigned int dma_pad_mask
;
409 unsigned int dma_alignment
;
411 struct blk_queue_tag
*queue_tags
;
412 struct list_head tag_busy_list
;
414 unsigned int nr_sorted
;
415 unsigned int in_flight
[2];
417 * Number of active block driver functions for which blk_drain_queue()
418 * must wait. Must be incremented around functions that unlock the
419 * queue_lock internally, e.g. scsi_request_fn().
421 unsigned int request_fn_active
;
423 unsigned int rq_timeout
;
424 struct timer_list timeout
;
425 struct work_struct timeout_work
;
426 struct list_head timeout_list
;
428 struct list_head icq_list
;
429 #ifdef CONFIG_BLK_CGROUP
430 DECLARE_BITMAP (blkcg_pols
, BLKCG_MAX_POLS
);
431 struct blkcg_gq
*root_blkg
;
432 struct list_head blkg_list
;
435 struct queue_limits limits
;
440 unsigned int sg_timeout
;
441 unsigned int sg_reserved_size
;
443 #ifdef CONFIG_BLK_DEV_IO_TRACE
444 struct blk_trace
*blk_trace
;
447 * for flush operations
449 struct blk_flush_queue
*fq
;
451 struct list_head requeue_list
;
452 spinlock_t requeue_lock
;
453 struct work_struct requeue_work
;
455 struct mutex sysfs_lock
;
458 atomic_t mq_freeze_depth
;
460 #if defined(CONFIG_BLK_DEV_BSG)
461 bsg_job_fn
*bsg_job_fn
;
463 struct bsg_class_device bsg_dev
;
466 #ifdef CONFIG_BLK_DEV_THROTTLING
468 struct throtl_data
*td
;
470 struct rcu_head rcu_head
;
471 wait_queue_head_t mq_freeze_wq
;
472 struct percpu_ref q_usage_counter
;
473 struct list_head all_q_node
;
475 struct blk_mq_tag_set
*tag_set
;
476 struct list_head tag_set_list
;
477 struct bio_set
*bio_split
;
479 bool mq_sysfs_init_done
;
482 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
483 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
484 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
485 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
486 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
487 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
488 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
489 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
490 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
491 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
492 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
493 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
494 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
495 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
496 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
497 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
498 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
499 #define QUEUE_FLAG_SECERASE 17 /* supports secure erase */
500 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
501 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
502 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
503 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
504 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
505 #define QUEUE_FLAG_WC 23 /* Write back caching */
506 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
507 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
508 #define QUEUE_FLAG_DAX 26 /* device supports DAX */
510 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
511 (1 << QUEUE_FLAG_STACKABLE) | \
512 (1 << QUEUE_FLAG_SAME_COMP) | \
513 (1 << QUEUE_FLAG_ADD_RANDOM))
515 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
516 (1 << QUEUE_FLAG_STACKABLE) | \
517 (1 << QUEUE_FLAG_SAME_COMP) | \
518 (1 << QUEUE_FLAG_POLL))
520 static inline void queue_lockdep_assert_held(struct request_queue
*q
)
523 lockdep_assert_held(q
->queue_lock
);
526 static inline void queue_flag_set_unlocked(unsigned int flag
,
527 struct request_queue
*q
)
529 __set_bit(flag
, &q
->queue_flags
);
532 static inline int queue_flag_test_and_clear(unsigned int flag
,
533 struct request_queue
*q
)
535 queue_lockdep_assert_held(q
);
537 if (test_bit(flag
, &q
->queue_flags
)) {
538 __clear_bit(flag
, &q
->queue_flags
);
545 static inline int queue_flag_test_and_set(unsigned int flag
,
546 struct request_queue
*q
)
548 queue_lockdep_assert_held(q
);
550 if (!test_bit(flag
, &q
->queue_flags
)) {
551 __set_bit(flag
, &q
->queue_flags
);
558 static inline void queue_flag_set(unsigned int flag
, struct request_queue
*q
)
560 queue_lockdep_assert_held(q
);
561 __set_bit(flag
, &q
->queue_flags
);
564 static inline void queue_flag_clear_unlocked(unsigned int flag
,
565 struct request_queue
*q
)
567 __clear_bit(flag
, &q
->queue_flags
);
570 static inline int queue_in_flight(struct request_queue
*q
)
572 return q
->in_flight
[0] + q
->in_flight
[1];
575 static inline void queue_flag_clear(unsigned int flag
, struct request_queue
*q
)
577 queue_lockdep_assert_held(q
);
578 __clear_bit(flag
, &q
->queue_flags
);
581 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
582 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
583 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
584 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
585 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
586 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
587 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
588 #define blk_queue_noxmerges(q) \
589 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
590 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
591 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
592 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
593 #define blk_queue_stackable(q) \
594 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
595 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
596 #define blk_queue_secure_erase(q) \
597 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
598 #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
600 #define blk_noretry_request(rq) \
601 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
602 REQ_FAILFAST_DRIVER))
604 #define blk_account_rq(rq) \
605 (((rq)->cmd_flags & REQ_STARTED) && \
606 ((rq)->cmd_type == REQ_TYPE_FS))
608 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
609 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
610 /* rq->queuelist of dequeued request must be list_empty() */
611 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
613 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
615 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
618 * Driver can handle struct request, if it either has an old style
619 * request_fn defined, or is blk-mq based.
621 static inline bool queue_is_rq_based(struct request_queue
*q
)
623 return q
->request_fn
|| q
->mq_ops
;
626 static inline unsigned int blk_queue_cluster(struct request_queue
*q
)
628 return q
->limits
.cluster
;
632 * We regard a request as sync, if either a read or a sync write
634 static inline bool rw_is_sync(int op
, unsigned int rw_flags
)
636 return op
== REQ_OP_READ
|| (rw_flags
& REQ_SYNC
);
639 static inline bool rq_is_sync(struct request
*rq
)
641 return rw_is_sync(req_op(rq
), rq
->cmd_flags
);
644 static inline bool blk_rl_full(struct request_list
*rl
, bool sync
)
646 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
648 return rl
->flags
& flag
;
651 static inline void blk_set_rl_full(struct request_list
*rl
, bool sync
)
653 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
658 static inline void blk_clear_rl_full(struct request_list
*rl
, bool sync
)
660 unsigned int flag
= sync
? BLK_RL_SYNCFULL
: BLK_RL_ASYNCFULL
;
665 static inline bool rq_mergeable(struct request
*rq
)
667 if (rq
->cmd_type
!= REQ_TYPE_FS
)
670 if (req_op(rq
) == REQ_OP_FLUSH
)
673 if (rq
->cmd_flags
& REQ_NOMERGE_FLAGS
)
679 static inline bool blk_write_same_mergeable(struct bio
*a
, struct bio
*b
)
681 if (bio_data(a
) == bio_data(b
))
688 * q->prep_rq_fn return values
691 BLKPREP_OK
, /* serve it */
692 BLKPREP_KILL
, /* fatal error, kill, return -EIO */
693 BLKPREP_DEFER
, /* leave on queue */
694 BLKPREP_INVALID
, /* invalid command, kill, return -EREMOTEIO */
697 extern unsigned long blk_max_low_pfn
, blk_max_pfn
;
700 * standard bounce addresses:
702 * BLK_BOUNCE_HIGH : bounce all highmem pages
703 * BLK_BOUNCE_ANY : don't bounce anything
704 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
707 #if BITS_PER_LONG == 32
708 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
710 #define BLK_BOUNCE_HIGH -1ULL
712 #define BLK_BOUNCE_ANY (-1ULL)
713 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
716 * default timeout for SG_IO if none specified
718 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
719 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
722 extern int init_emergency_isa_pool(void);
723 extern void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
);
725 static inline int init_emergency_isa_pool(void)
729 static inline void blk_queue_bounce(struct request_queue
*q
, struct bio
**bio
)
732 #endif /* CONFIG_MMU */
738 unsigned long offset
;
743 struct req_iterator
{
744 struct bvec_iter iter
;
748 /* This should not be used directly - use rq_for_each_segment */
749 #define for_each_bio(_bio) \
750 for (; _bio; _bio = _bio->bi_next)
751 #define __rq_for_each_bio(_bio, rq) \
753 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
755 #define rq_for_each_segment(bvl, _rq, _iter) \
756 __rq_for_each_bio(_iter.bio, _rq) \
757 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
759 #define rq_iter_last(bvec, _iter) \
760 (_iter.bio->bi_next == NULL && \
761 bio_iter_last(bvec, _iter.iter))
763 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
764 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
766 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
767 extern void rq_flush_dcache_pages(struct request
*rq
);
769 static inline void rq_flush_dcache_pages(struct request
*rq
)
775 #define vfs_msg(sb, level, fmt, ...) \
776 __vfs_msg(sb, level, fmt, ##__VA_ARGS__)
778 #define vfs_msg(sb, level, fmt, ...) \
780 no_printk(fmt, ##__VA_ARGS__); \
781 __vfs_msg(sb, "", " "); \
785 extern int blk_register_queue(struct gendisk
*disk
);
786 extern void blk_unregister_queue(struct gendisk
*disk
);
787 extern blk_qc_t
generic_make_request(struct bio
*bio
);
788 extern void blk_rq_init(struct request_queue
*q
, struct request
*rq
);
789 extern void blk_put_request(struct request
*);
790 extern void __blk_put_request(struct request_queue
*, struct request
*);
791 extern struct request
*blk_get_request(struct request_queue
*, int, gfp_t
);
792 extern void blk_rq_set_block_pc(struct request
*);
793 extern void blk_requeue_request(struct request_queue
*, struct request
*);
794 extern void blk_add_request_payload(struct request
*rq
, struct page
*page
,
795 int offset
, unsigned int len
);
796 extern int blk_lld_busy(struct request_queue
*q
);
797 extern int blk_rq_prep_clone(struct request
*rq
, struct request
*rq_src
,
798 struct bio_set
*bs
, gfp_t gfp_mask
,
799 int (*bio_ctr
)(struct bio
*, struct bio
*, void *),
801 extern void blk_rq_unprep_clone(struct request
*rq
);
802 extern int blk_insert_cloned_request(struct request_queue
*q
,
804 extern int blk_rq_append_bio(struct request
*rq
, struct bio
*bio
);
805 extern void blk_delay_queue(struct request_queue
*, unsigned long);
806 extern void blk_queue_split(struct request_queue
*, struct bio
**,
808 extern void blk_recount_segments(struct request_queue
*, struct bio
*);
809 extern int scsi_verify_blk_ioctl(struct block_device
*, unsigned int);
810 extern int scsi_cmd_blk_ioctl(struct block_device
*, fmode_t
,
811 unsigned int, void __user
*);
812 extern int scsi_cmd_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
813 unsigned int, void __user
*);
814 extern int sg_scsi_ioctl(struct request_queue
*, struct gendisk
*, fmode_t
,
815 struct scsi_ioctl_command __user
*);
817 extern int blk_queue_enter(struct request_queue
*q
, bool nowait
);
818 extern void blk_queue_exit(struct request_queue
*q
);
819 extern void blk_start_queue(struct request_queue
*q
);
820 extern void blk_start_queue_async(struct request_queue
*q
);
821 extern void blk_stop_queue(struct request_queue
*q
);
822 extern void blk_sync_queue(struct request_queue
*q
);
823 extern void __blk_stop_queue(struct request_queue
*q
);
824 extern void __blk_run_queue(struct request_queue
*q
);
825 extern void __blk_run_queue_uncond(struct request_queue
*q
);
826 extern void blk_run_queue(struct request_queue
*);
827 extern void blk_run_queue_async(struct request_queue
*q
);
828 extern int blk_rq_map_user(struct request_queue
*, struct request
*,
829 struct rq_map_data
*, void __user
*, unsigned long,
831 extern int blk_rq_unmap_user(struct bio
*);
832 extern int blk_rq_map_kern(struct request_queue
*, struct request
*, void *, unsigned int, gfp_t
);
833 extern int blk_rq_map_user_iov(struct request_queue
*, struct request
*,
834 struct rq_map_data
*, const struct iov_iter
*,
836 extern int blk_execute_rq(struct request_queue
*, struct gendisk
*,
837 struct request
*, int);
838 extern void blk_execute_rq_nowait(struct request_queue
*, struct gendisk
*,
839 struct request
*, int, rq_end_io_fn
*);
841 bool blk_poll(struct request_queue
*q
, blk_qc_t cookie
);
843 static inline struct request_queue
*bdev_get_queue(struct block_device
*bdev
)
845 return bdev
->bd_disk
->queue
; /* this is never NULL */
849 * blk_rq_pos() : the current sector
850 * blk_rq_bytes() : bytes left in the entire request
851 * blk_rq_cur_bytes() : bytes left in the current segment
852 * blk_rq_err_bytes() : bytes left till the next error boundary
853 * blk_rq_sectors() : sectors left in the entire request
854 * blk_rq_cur_sectors() : sectors left in the current segment
856 static inline sector_t
blk_rq_pos(const struct request
*rq
)
861 static inline unsigned int blk_rq_bytes(const struct request
*rq
)
863 return rq
->__data_len
;
866 static inline int blk_rq_cur_bytes(const struct request
*rq
)
868 return rq
->bio
? bio_cur_bytes(rq
->bio
) : 0;
871 extern unsigned int blk_rq_err_bytes(const struct request
*rq
);
873 static inline unsigned int blk_rq_sectors(const struct request
*rq
)
875 return blk_rq_bytes(rq
) >> 9;
878 static inline unsigned int blk_rq_cur_sectors(const struct request
*rq
)
880 return blk_rq_cur_bytes(rq
) >> 9;
883 static inline unsigned int blk_queue_get_max_sectors(struct request_queue
*q
,
886 if (unlikely(op
== REQ_OP_DISCARD
))
887 return min(q
->limits
.max_discard_sectors
, UINT_MAX
>> 9);
889 if (unlikely(op
== REQ_OP_WRITE_SAME
))
890 return q
->limits
.max_write_same_sectors
;
892 return q
->limits
.max_sectors
;
896 * Return maximum size of a request at given offset. Only valid for
897 * file system requests.
899 static inline unsigned int blk_max_size_offset(struct request_queue
*q
,
902 if (!q
->limits
.chunk_sectors
)
903 return q
->limits
.max_sectors
;
905 return q
->limits
.chunk_sectors
-
906 (offset
& (q
->limits
.chunk_sectors
- 1));
909 static inline unsigned int blk_rq_get_max_sectors(struct request
*rq
,
912 struct request_queue
*q
= rq
->q
;
914 if (unlikely(rq
->cmd_type
!= REQ_TYPE_FS
))
915 return q
->limits
.max_hw_sectors
;
917 if (!q
->limits
.chunk_sectors
|| (req_op(rq
) == REQ_OP_DISCARD
))
918 return blk_queue_get_max_sectors(q
, req_op(rq
));
920 return min(blk_max_size_offset(q
, offset
),
921 blk_queue_get_max_sectors(q
, req_op(rq
)));
924 static inline unsigned int blk_rq_count_bios(struct request
*rq
)
926 unsigned int nr_bios
= 0;
929 __rq_for_each_bio(bio
, rq
)
936 * Request issue related functions.
938 extern struct request
*blk_peek_request(struct request_queue
*q
);
939 extern void blk_start_request(struct request
*rq
);
940 extern struct request
*blk_fetch_request(struct request_queue
*q
);
943 * Request completion related functions.
945 * blk_update_request() completes given number of bytes and updates
946 * the request without completing it.
948 * blk_end_request() and friends. __blk_end_request() must be called
949 * with the request queue spinlock acquired.
951 * Several drivers define their own end_request and call
952 * blk_end_request() for parts of the original function.
953 * This prevents code duplication in drivers.
955 extern bool blk_update_request(struct request
*rq
, int error
,
956 unsigned int nr_bytes
);
957 extern void blk_finish_request(struct request
*rq
, int error
);
958 extern bool blk_end_request(struct request
*rq
, int error
,
959 unsigned int nr_bytes
);
960 extern void blk_end_request_all(struct request
*rq
, int error
);
961 extern bool blk_end_request_cur(struct request
*rq
, int error
);
962 extern bool blk_end_request_err(struct request
*rq
, int error
);
963 extern bool __blk_end_request(struct request
*rq
, int error
,
964 unsigned int nr_bytes
);
965 extern void __blk_end_request_all(struct request
*rq
, int error
);
966 extern bool __blk_end_request_cur(struct request
*rq
, int error
);
967 extern bool __blk_end_request_err(struct request
*rq
, int error
);
969 extern void blk_complete_request(struct request
*);
970 extern void __blk_complete_request(struct request
*);
971 extern void blk_abort_request(struct request
*);
972 extern void blk_unprep_request(struct request
*);
975 * Access functions for manipulating queue properties
977 extern struct request_queue
*blk_init_queue_node(request_fn_proc
*rfn
,
978 spinlock_t
*lock
, int node_id
);
979 extern struct request_queue
*blk_init_queue(request_fn_proc
*, spinlock_t
*);
980 extern struct request_queue
*blk_init_allocated_queue(struct request_queue
*,
981 request_fn_proc
*, spinlock_t
*);
982 extern void blk_cleanup_queue(struct request_queue
*);
983 extern void blk_queue_make_request(struct request_queue
*, make_request_fn
*);
984 extern void blk_queue_bounce_limit(struct request_queue
*, u64
);
985 extern void blk_queue_max_hw_sectors(struct request_queue
*, unsigned int);
986 extern void blk_queue_chunk_sectors(struct request_queue
*, unsigned int);
987 extern void blk_queue_max_segments(struct request_queue
*, unsigned short);
988 extern void blk_queue_max_segment_size(struct request_queue
*, unsigned int);
989 extern void blk_queue_max_discard_sectors(struct request_queue
*q
,
990 unsigned int max_discard_sectors
);
991 extern void blk_queue_max_write_same_sectors(struct request_queue
*q
,
992 unsigned int max_write_same_sectors
);
993 extern void blk_queue_logical_block_size(struct request_queue
*, unsigned short);
994 extern void blk_queue_physical_block_size(struct request_queue
*, unsigned int);
995 extern void blk_queue_alignment_offset(struct request_queue
*q
,
996 unsigned int alignment
);
997 extern void blk_limits_io_min(struct queue_limits
*limits
, unsigned int min
);
998 extern void blk_queue_io_min(struct request_queue
*q
, unsigned int min
);
999 extern void blk_limits_io_opt(struct queue_limits
*limits
, unsigned int opt
);
1000 extern void blk_queue_io_opt(struct request_queue
*q
, unsigned int opt
);
1001 extern void blk_set_default_limits(struct queue_limits
*lim
);
1002 extern void blk_set_stacking_limits(struct queue_limits
*lim
);
1003 extern int blk_stack_limits(struct queue_limits
*t
, struct queue_limits
*b
,
1005 extern int bdev_stack_limits(struct queue_limits
*t
, struct block_device
*bdev
,
1007 extern void disk_stack_limits(struct gendisk
*disk
, struct block_device
*bdev
,
1009 extern void blk_queue_stack_limits(struct request_queue
*t
, struct request_queue
*b
);
1010 extern void blk_queue_dma_pad(struct request_queue
*, unsigned int);
1011 extern void blk_queue_update_dma_pad(struct request_queue
*, unsigned int);
1012 extern int blk_queue_dma_drain(struct request_queue
*q
,
1013 dma_drain_needed_fn
*dma_drain_needed
,
1014 void *buf
, unsigned int size
);
1015 extern void blk_queue_lld_busy(struct request_queue
*q
, lld_busy_fn
*fn
);
1016 extern void blk_queue_segment_boundary(struct request_queue
*, unsigned long);
1017 extern void blk_queue_virt_boundary(struct request_queue
*, unsigned long);
1018 extern void blk_queue_prep_rq(struct request_queue
*, prep_rq_fn
*pfn
);
1019 extern void blk_queue_unprep_rq(struct request_queue
*, unprep_rq_fn
*ufn
);
1020 extern void blk_queue_dma_alignment(struct request_queue
*, int);
1021 extern void blk_queue_update_dma_alignment(struct request_queue
*, int);
1022 extern void blk_queue_softirq_done(struct request_queue
*, softirq_done_fn
*);
1023 extern void blk_queue_rq_timed_out(struct request_queue
*, rq_timed_out_fn
*);
1024 extern void blk_queue_rq_timeout(struct request_queue
*, unsigned int);
1025 extern void blk_queue_flush_queueable(struct request_queue
*q
, bool queueable
);
1026 extern void blk_queue_write_cache(struct request_queue
*q
, bool enabled
, bool fua
);
1027 extern struct backing_dev_info
*blk_get_backing_dev_info(struct block_device
*bdev
);
1029 extern int blk_rq_map_sg(struct request_queue
*, struct request
*, struct scatterlist
*);
1030 extern void blk_dump_rq_flags(struct request
*, char *);
1031 extern long nr_blockdev_pages(void);
1033 bool __must_check
blk_get_queue(struct request_queue
*);
1034 struct request_queue
*blk_alloc_queue(gfp_t
);
1035 struct request_queue
*blk_alloc_queue_node(gfp_t
, int);
1036 extern void blk_put_queue(struct request_queue
*);
1037 extern void blk_set_queue_dying(struct request_queue
*);
1040 * block layer runtime pm functions
1043 extern void blk_pm_runtime_init(struct request_queue
*q
, struct device
*dev
);
1044 extern int blk_pre_runtime_suspend(struct request_queue
*q
);
1045 extern void blk_post_runtime_suspend(struct request_queue
*q
, int err
);
1046 extern void blk_pre_runtime_resume(struct request_queue
*q
);
1047 extern void blk_post_runtime_resume(struct request_queue
*q
, int err
);
1048 extern void blk_set_runtime_active(struct request_queue
*q
);
1050 static inline void blk_pm_runtime_init(struct request_queue
*q
,
1051 struct device
*dev
) {}
1052 static inline int blk_pre_runtime_suspend(struct request_queue
*q
)
1056 static inline void blk_post_runtime_suspend(struct request_queue
*q
, int err
) {}
1057 static inline void blk_pre_runtime_resume(struct request_queue
*q
) {}
1058 static inline void blk_post_runtime_resume(struct request_queue
*q
, int err
) {}
1059 extern inline void blk_set_runtime_active(struct request_queue
*q
) {}
1063 * blk_plug permits building a queue of related requests by holding the I/O
1064 * fragments for a short period. This allows merging of sequential requests
1065 * into single larger request. As the requests are moved from a per-task list to
1066 * the device's request_queue in a batch, this results in improved scalability
1067 * as the lock contention for request_queue lock is reduced.
1069 * It is ok not to disable preemption when adding the request to the plug list
1070 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1071 * the plug list when the task sleeps by itself. For details, please see
1072 * schedule() where blk_schedule_flush_plug() is called.
1075 struct list_head list
; /* requests */
1076 struct list_head mq_list
; /* blk-mq requests */
1077 struct list_head cb_list
; /* md requires an unplug callback */
1079 #define BLK_MAX_REQUEST_COUNT 16
1082 typedef void (*blk_plug_cb_fn
)(struct blk_plug_cb
*, bool);
1083 struct blk_plug_cb
{
1084 struct list_head list
;
1085 blk_plug_cb_fn callback
;
1088 extern struct blk_plug_cb
*blk_check_plugged(blk_plug_cb_fn unplug
,
1089 void *data
, int size
);
1090 extern void blk_start_plug(struct blk_plug
*);
1091 extern void blk_finish_plug(struct blk_plug
*);
1092 extern void blk_flush_plug_list(struct blk_plug
*, bool);
1094 static inline void blk_flush_plug(struct task_struct
*tsk
)
1096 struct blk_plug
*plug
= tsk
->plug
;
1099 blk_flush_plug_list(plug
, false);
1102 static inline void blk_schedule_flush_plug(struct task_struct
*tsk
)
1104 struct blk_plug
*plug
= tsk
->plug
;
1107 blk_flush_plug_list(plug
, true);
1110 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1112 struct blk_plug
*plug
= tsk
->plug
;
1115 (!list_empty(&plug
->list
) ||
1116 !list_empty(&plug
->mq_list
) ||
1117 !list_empty(&plug
->cb_list
));
1123 extern int blk_queue_start_tag(struct request_queue
*, struct request
*);
1124 extern struct request
*blk_queue_find_tag(struct request_queue
*, int);
1125 extern void blk_queue_end_tag(struct request_queue
*, struct request
*);
1126 extern int blk_queue_init_tags(struct request_queue
*, int, struct blk_queue_tag
*, int);
1127 extern void blk_queue_free_tags(struct request_queue
*);
1128 extern int blk_queue_resize_tags(struct request_queue
*, int);
1129 extern void blk_queue_invalidate_tags(struct request_queue
*);
1130 extern struct blk_queue_tag
*blk_init_tags(int, int);
1131 extern void blk_free_tags(struct blk_queue_tag
*);
1133 static inline struct request
*blk_map_queue_find_tag(struct blk_queue_tag
*bqt
,
1136 if (unlikely(bqt
== NULL
|| tag
>= bqt
->real_max_depth
))
1138 return bqt
->tag_index
[tag
];
1142 #define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */
1143 #define BLKDEV_DISCARD_ZERO (1 << 1) /* must reliably zero data */
1145 extern int blkdev_issue_flush(struct block_device
*, gfp_t
, sector_t
*);
1146 extern int blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
1147 sector_t nr_sects
, gfp_t gfp_mask
, unsigned long flags
);
1148 extern int __blkdev_issue_discard(struct block_device
*bdev
, sector_t sector
,
1149 sector_t nr_sects
, gfp_t gfp_mask
, int flags
,
1151 extern int blkdev_issue_write_same(struct block_device
*bdev
, sector_t sector
,
1152 sector_t nr_sects
, gfp_t gfp_mask
, struct page
*page
);
1153 extern int blkdev_issue_zeroout(struct block_device
*bdev
, sector_t sector
,
1154 sector_t nr_sects
, gfp_t gfp_mask
, bool discard
);
1155 static inline int sb_issue_discard(struct super_block
*sb
, sector_t block
,
1156 sector_t nr_blocks
, gfp_t gfp_mask
, unsigned long flags
)
1158 return blkdev_issue_discard(sb
->s_bdev
, block
<< (sb
->s_blocksize_bits
- 9),
1159 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1162 static inline int sb_issue_zeroout(struct super_block
*sb
, sector_t block
,
1163 sector_t nr_blocks
, gfp_t gfp_mask
)
1165 return blkdev_issue_zeroout(sb
->s_bdev
,
1166 block
<< (sb
->s_blocksize_bits
- 9),
1167 nr_blocks
<< (sb
->s_blocksize_bits
- 9),
1171 extern int blk_verify_command(unsigned char *cmd
, fmode_t has_write_perm
);
1173 enum blk_default_limits
{
1174 BLK_MAX_SEGMENTS
= 128,
1175 BLK_SAFE_MAX_SECTORS
= 255,
1176 BLK_DEF_MAX_SECTORS
= 2560,
1177 BLK_MAX_SEGMENT_SIZE
= 65536,
1178 BLK_SEG_BOUNDARY_MASK
= 0xFFFFFFFFUL
,
1181 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1183 static inline unsigned long queue_bounce_pfn(struct request_queue
*q
)
1185 return q
->limits
.bounce_pfn
;
1188 static inline unsigned long queue_segment_boundary(struct request_queue
*q
)
1190 return q
->limits
.seg_boundary_mask
;
1193 static inline unsigned long queue_virt_boundary(struct request_queue
*q
)
1195 return q
->limits
.virt_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 !test_bit(QUEUE_FLAG_FLUSH_NQ
, &q
->queue_flags
);
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
)
1398 static inline bool __bvec_gap_to_prev(struct request_queue
*q
,
1399 struct bio_vec
*bprv
, unsigned int offset
)
1402 ((bprv
->bv_offset
+ bprv
->bv_len
) & queue_virt_boundary(q
));
1406 * Check if adding a bio_vec after bprv with offset would create a gap in
1407 * the SG list. Most drivers don't care about this, but some do.
1409 static inline bool bvec_gap_to_prev(struct request_queue
*q
,
1410 struct bio_vec
*bprv
, unsigned int offset
)
1412 if (!queue_virt_boundary(q
))
1414 return __bvec_gap_to_prev(q
, bprv
, offset
);
1417 static inline bool bio_will_gap(struct request_queue
*q
, struct bio
*prev
,
1420 if (bio_has_data(prev
) && queue_virt_boundary(q
)) {
1421 struct bio_vec pb
, nb
;
1423 bio_get_last_bvec(prev
, &pb
);
1424 bio_get_first_bvec(next
, &nb
);
1426 return __bvec_gap_to_prev(q
, &pb
, nb
.bv_offset
);
1432 static inline bool req_gap_back_merge(struct request
*req
, struct bio
*bio
)
1434 return bio_will_gap(req
->q
, req
->biotail
, bio
);
1437 static inline bool req_gap_front_merge(struct request
*req
, struct bio
*bio
)
1439 return bio_will_gap(req
->q
, bio
, req
->bio
);
1443 int kblockd_schedule_work(struct work_struct
*work
);
1444 int kblockd_schedule_delayed_work(struct delayed_work
*dwork
, unsigned long delay
);
1445 int kblockd_schedule_delayed_work_on(int cpu
, struct delayed_work
*dwork
, unsigned long delay
);
1447 #ifdef CONFIG_BLK_CGROUP
1449 * This should not be using sched_clock(). A real patch is in progress
1450 * to fix this up, until that is in place we need to disable preemption
1451 * around sched_clock() in this function and set_io_start_time_ns().
1453 static inline void set_start_time_ns(struct request
*req
)
1456 req
->start_time_ns
= sched_clock();
1460 static inline void set_io_start_time_ns(struct request
*req
)
1463 req
->io_start_time_ns
= sched_clock();
1467 static inline uint64_t rq_start_time_ns(struct request
*req
)
1469 return req
->start_time_ns
;
1472 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1474 return req
->io_start_time_ns
;
1477 static inline void set_start_time_ns(struct request
*req
) {}
1478 static inline void set_io_start_time_ns(struct request
*req
) {}
1479 static inline uint64_t rq_start_time_ns(struct request
*req
)
1483 static inline uint64_t rq_io_start_time_ns(struct request
*req
)
1489 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1490 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1491 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1492 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1494 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1496 enum blk_integrity_flags
{
1497 BLK_INTEGRITY_VERIFY
= 1 << 0,
1498 BLK_INTEGRITY_GENERATE
= 1 << 1,
1499 BLK_INTEGRITY_DEVICE_CAPABLE
= 1 << 2,
1500 BLK_INTEGRITY_IP_CHECKSUM
= 1 << 3,
1503 struct blk_integrity_iter
{
1507 unsigned int data_size
;
1508 unsigned short interval
;
1509 const char *disk_name
;
1512 typedef int (integrity_processing_fn
) (struct blk_integrity_iter
*);
1514 struct blk_integrity_profile
{
1515 integrity_processing_fn
*generate_fn
;
1516 integrity_processing_fn
*verify_fn
;
1520 extern void blk_integrity_register(struct gendisk
*, struct blk_integrity
*);
1521 extern void blk_integrity_unregister(struct gendisk
*);
1522 extern int blk_integrity_compare(struct gendisk
*, struct gendisk
*);
1523 extern int blk_rq_map_integrity_sg(struct request_queue
*, struct bio
*,
1524 struct scatterlist
*);
1525 extern int blk_rq_count_integrity_sg(struct request_queue
*, struct bio
*);
1526 extern bool blk_integrity_merge_rq(struct request_queue
*, struct request
*,
1528 extern bool blk_integrity_merge_bio(struct request_queue
*, struct request
*,
1531 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1533 struct blk_integrity
*bi
= &disk
->queue
->integrity
;
1542 struct blk_integrity
*bdev_get_integrity(struct block_device
*bdev
)
1544 return blk_get_integrity(bdev
->bd_disk
);
1547 static inline bool blk_integrity_rq(struct request
*rq
)
1549 return rq
->cmd_flags
& REQ_INTEGRITY
;
1552 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1555 q
->limits
.max_integrity_segments
= segs
;
1558 static inline unsigned short
1559 queue_max_integrity_segments(struct request_queue
*q
)
1561 return q
->limits
.max_integrity_segments
;
1564 static inline bool integrity_req_gap_back_merge(struct request
*req
,
1567 struct bio_integrity_payload
*bip
= bio_integrity(req
->bio
);
1568 struct bio_integrity_payload
*bip_next
= bio_integrity(next
);
1570 return bvec_gap_to_prev(req
->q
, &bip
->bip_vec
[bip
->bip_vcnt
- 1],
1571 bip_next
->bip_vec
[0].bv_offset
);
1574 static inline bool integrity_req_gap_front_merge(struct request
*req
,
1577 struct bio_integrity_payload
*bip
= bio_integrity(bio
);
1578 struct bio_integrity_payload
*bip_next
= bio_integrity(req
->bio
);
1580 return bvec_gap_to_prev(req
->q
, &bip
->bip_vec
[bip
->bip_vcnt
- 1],
1581 bip_next
->bip_vec
[0].bv_offset
);
1584 #else /* CONFIG_BLK_DEV_INTEGRITY */
1587 struct block_device
;
1589 struct blk_integrity
;
1591 static inline int blk_integrity_rq(struct request
*rq
)
1595 static inline int blk_rq_count_integrity_sg(struct request_queue
*q
,
1600 static inline int blk_rq_map_integrity_sg(struct request_queue
*q
,
1602 struct scatterlist
*s
)
1606 static inline struct blk_integrity
*bdev_get_integrity(struct block_device
*b
)
1610 static inline struct blk_integrity
*blk_get_integrity(struct gendisk
*disk
)
1614 static inline int blk_integrity_compare(struct gendisk
*a
, struct gendisk
*b
)
1618 static inline void blk_integrity_register(struct gendisk
*d
,
1619 struct blk_integrity
*b
)
1622 static inline void blk_integrity_unregister(struct gendisk
*d
)
1625 static inline void blk_queue_max_integrity_segments(struct request_queue
*q
,
1629 static inline unsigned short queue_max_integrity_segments(struct request_queue
*q
)
1633 static inline bool blk_integrity_merge_rq(struct request_queue
*rq
,
1639 static inline bool blk_integrity_merge_bio(struct request_queue
*rq
,
1646 static inline bool integrity_req_gap_back_merge(struct request
*req
,
1651 static inline bool integrity_req_gap_front_merge(struct request
*req
,
1657 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1660 * struct blk_dax_ctl - control and output parameters for ->direct_access
1661 * @sector: (input) offset relative to a block_device
1662 * @addr: (output) kernel virtual address for @sector populated by driver
1663 * @pfn: (output) page frame number for @addr populated by driver
1664 * @size: (input) number of bytes requested
1666 struct blk_dax_ctl
{
1673 struct block_device_operations
{
1674 int (*open
) (struct block_device
*, fmode_t
);
1675 void (*release
) (struct gendisk
*, fmode_t
);
1676 int (*rw_page
)(struct block_device
*, sector_t
, struct page
*, int rw
);
1677 int (*ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1678 int (*compat_ioctl
) (struct block_device
*, fmode_t
, unsigned, unsigned long);
1679 long (*direct_access
)(struct block_device
*, sector_t
, void **, pfn_t
*,
1681 unsigned int (*check_events
) (struct gendisk
*disk
,
1682 unsigned int clearing
);
1683 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1684 int (*media_changed
) (struct gendisk
*);
1685 void (*unlock_native_capacity
) (struct gendisk
*);
1686 int (*revalidate_disk
) (struct gendisk
*);
1687 int (*getgeo
)(struct block_device
*, struct hd_geometry
*);
1688 /* this callback is with swap_lock and sometimes page table lock held */
1689 void (*swap_slot_free_notify
) (struct block_device
*, unsigned long);
1690 struct module
*owner
;
1691 const struct pr_ops
*pr_ops
;
1694 extern int __blkdev_driver_ioctl(struct block_device
*, fmode_t
, unsigned int,
1696 extern int bdev_read_page(struct block_device
*, sector_t
, struct page
*);
1697 extern int bdev_write_page(struct block_device
*, sector_t
, struct page
*,
1698 struct writeback_control
*);
1699 extern long bdev_direct_access(struct block_device
*, struct blk_dax_ctl
*);
1700 extern int bdev_dax_supported(struct super_block
*, int);
1701 extern bool bdev_dax_capable(struct block_device
*);
1702 #else /* CONFIG_BLOCK */
1704 struct block_device
;
1707 * stubs for when the block layer is configured out
1709 #define buffer_heads_over_limit 0
1711 static inline long nr_blockdev_pages(void)
1719 static inline void blk_start_plug(struct blk_plug
*plug
)
1723 static inline void blk_finish_plug(struct blk_plug
*plug
)
1727 static inline void blk_flush_plug(struct task_struct
*task
)
1731 static inline void blk_schedule_flush_plug(struct task_struct
*task
)
1736 static inline bool blk_needs_flush_plug(struct task_struct
*tsk
)
1741 static inline int blkdev_issue_flush(struct block_device
*bdev
, gfp_t gfp_mask
,
1742 sector_t
*error_sector
)
1747 #endif /* CONFIG_BLOCK */