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_SENSE, /* sense request */
79 REQ_TYPE_PM_SUSPEND, /* suspend request */
80 REQ_TYPE_PM_RESUME, /* resume request */
81 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */
82 REQ_TYPE_SPECIAL, /* driver defined type */
84 * for ATA/ATAPI devices. this really doesn't belong here, ide should
85 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
86 * private REQ_LB opcodes to differentiate what type of request this is
88 REQ_TYPE_ATA_TASKFILE,
92 #define BLK_MAX_CDB 16
95 * Try to put the fields that are referenced together in the same cacheline.
97 * If you modify this structure, make sure to update blk_rq_init() and
98 * especially blk_mq_rq_ctx_init() to take care of the added fields.
101 struct list_head queuelist;
103 struct call_single_data csd;
104 unsigned long fifo_time;
107 struct request_queue *q;
108 struct blk_mq_ctx *mq_ctx;
111 enum rq_cmd_type_bits cmd_type;
112 unsigned long atomic_flags;
116 /* the following two fields are internal, NEVER access directly */
117 unsigned int __data_len; /* total data len */
118 sector_t __sector; /* sector cursor */
124 * The hash is used inside the scheduler, and killed once the
125 * request reaches the dispatch list. The ipi_list is only used
126 * to queue the request for softirq completion, which is long
127 * after the request has been unhashed (and even removed from
128 * the dispatch list).
131 struct hlist_node hash; /* merge hash */
132 struct list_head ipi_list;
136 * The rb_node is only used inside the io scheduler, requests
137 * are pruned when moved to the dispatch queue. So let the
138 * completion_data share space with the rb_node.
141 struct rb_node rb_node; /* sort/lookup */
142 void *completion_data;
146 * Three pointers are available for the IO schedulers, if they need
147 * more they have to dynamically allocate it. Flush requests are
148 * never put on the IO scheduler. So let the flush fields share
149 * space with the elevator data.
159 struct list_head list;
160 rq_end_io_fn *saved_end_io;
164 struct gendisk *rq_disk;
165 struct hd_struct *part;
166 unsigned long start_time;
167 #ifdef CONFIG_BLK_CGROUP
168 struct request_list *rl; /* rl this rq is alloced from */
169 unsigned long long start_time_ns;
170 unsigned long long io_start_time_ns; /* when passed to hardware */
172 /* Number of scatter-gather DMA addr+len pairs after
173 * physical address coalescing is performed.
175 unsigned short nr_phys_segments;
176 #if defined(CONFIG_BLK_DEV_INTEGRITY)
177 unsigned short nr_integrity_segments;
180 unsigned short ioprio;
182 void *special; /* opaque pointer available for LLD use */
188 * when request is used as a packet command carrier
190 unsigned char __cmd[BLK_MAX_CDB];
192 unsigned short cmd_len;
194 unsigned int extra_len; /* length of alignment and padding */
195 unsigned int sense_len;
196 unsigned int resid_len; /* residual count */
199 unsigned long deadline;
200 struct list_head timeout_list;
201 unsigned int timeout;
205 * completion callback.
207 rq_end_io_fn *end_io;
211 struct request *next_rq;
214 static inline unsigned short req_get_ioprio(struct request *req)
220 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
221 * requests. Some step values could eventually be made generic.
223 struct request_pm_state
225 /* PM state machine step value, currently driver specific */
227 /* requested PM state value (S1, S2, S3, S4, ...) */
229 void* data; /* for driver use */
232 #include <linux/elevator.h>
234 struct blk_queue_ctx;
236 typedef void (request_fn_proc) (struct request_queue *q);
237 typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
238 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
239 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
242 struct bvec_merge_data {
243 struct block_device *bi_bdev;
248 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
250 typedef void (softirq_done_fn)(struct request *);
251 typedef int (dma_drain_needed_fn)(struct request *);
252 typedef int (lld_busy_fn) (struct request_queue *q);
253 typedef int (bsg_job_fn) (struct bsg_job *);
255 enum blk_eh_timer_return {
261 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
263 enum blk_queue_state {
268 struct blk_queue_tag {
269 struct request **tag_index; /* map of busy tags */
270 unsigned long *tag_map; /* bit map of free/busy tags */
271 int busy; /* current depth */
272 int max_depth; /* what we will send to device */
273 int real_max_depth; /* what the array can hold */
274 atomic_t refcnt; /* map can be shared */
277 #define BLK_SCSI_MAX_CMDS (256)
278 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
280 struct queue_limits {
281 unsigned long bounce_pfn;
282 unsigned long seg_boundary_mask;
284 unsigned int max_hw_sectors;
285 unsigned int chunk_sectors;
286 unsigned int max_sectors;
287 unsigned int max_segment_size;
288 unsigned int physical_block_size;
289 unsigned int alignment_offset;
292 unsigned int max_discard_sectors;
293 unsigned int max_write_same_sectors;
294 unsigned int discard_granularity;
295 unsigned int discard_alignment;
297 unsigned short logical_block_size;
298 unsigned short max_segments;
299 unsigned short max_integrity_segments;
301 unsigned char misaligned;
302 unsigned char discard_misaligned;
303 unsigned char cluster;
304 unsigned char discard_zeroes_data;
305 unsigned char raid_partial_stripes_expensive;
308 struct request_queue {
310 * Together with queue_head for cacheline sharing
312 struct list_head queue_head;
313 struct request *last_merge;
314 struct elevator_queue *elevator;
315 int nr_rqs[2]; /* # allocated [a]sync rqs */
316 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
319 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
320 * is used, root blkg allocates from @q->root_rl and all other
321 * blkgs from their own blkg->rl. Which one to use should be
322 * determined using bio_request_list().
324 struct request_list root_rl;
326 request_fn_proc *request_fn;
327 make_request_fn *make_request_fn;
328 prep_rq_fn *prep_rq_fn;
329 unprep_rq_fn *unprep_rq_fn;
330 merge_bvec_fn *merge_bvec_fn;
331 softirq_done_fn *softirq_done_fn;
332 rq_timed_out_fn *rq_timed_out_fn;
333 dma_drain_needed_fn *dma_drain_needed;
334 lld_busy_fn *lld_busy_fn;
336 struct blk_mq_ops *mq_ops;
338 unsigned int *mq_map;
341 struct blk_mq_ctx __percpu *queue_ctx;
342 unsigned int nr_queues;
344 /* hw dispatch queues */
345 struct blk_mq_hw_ctx **queue_hw_ctx;
346 unsigned int nr_hw_queues;
349 * Dispatch queue sorting
352 struct request *boundary_rq;
355 * Delayed queue handling
357 struct delayed_work delay_work;
359 struct backing_dev_info backing_dev_info;
362 * The queue owner gets to use this for whatever they like.
363 * ll_rw_blk doesn't touch it.
368 * various queue flags, see QUEUE_* below
370 unsigned long queue_flags;
373 * ida allocated id for this queue. Used to index queues from
379 * queue needs bounce pages for pages above this limit
384 * protects queue structures from reentrancy. ->__queue_lock should
385 * _never_ be used directly, it is queue private. always use
388 spinlock_t __queue_lock;
389 spinlock_t *queue_lock;
399 struct kobject mq_kobj;
401 #ifdef CONFIG_PM_RUNTIME
404 unsigned int nr_pending;
410 unsigned long nr_requests; /* Max # of requests */
411 unsigned int nr_congestion_on;
412 unsigned int nr_congestion_off;
413 unsigned int nr_batching;
415 unsigned int dma_drain_size;
416 void *dma_drain_buffer;
417 unsigned int dma_pad_mask;
418 unsigned int dma_alignment;
420 struct blk_queue_tag *queue_tags;
421 struct list_head tag_busy_list;
423 unsigned int nr_sorted;
424 unsigned int in_flight[2];
426 * Number of active block driver functions for which blk_drain_queue()
427 * must wait. Must be incremented around functions that unlock the
428 * queue_lock internally, e.g. scsi_request_fn().
430 unsigned int request_fn_active;
432 unsigned int rq_timeout;
433 struct timer_list timeout;
434 struct list_head timeout_list;
436 struct list_head icq_list;
437 #ifdef CONFIG_BLK_CGROUP
438 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
439 struct blkcg_gq *root_blkg;
440 struct list_head blkg_list;
443 struct queue_limits limits;
448 unsigned int sg_timeout;
449 unsigned int sg_reserved_size;
451 #ifdef CONFIG_BLK_DEV_IO_TRACE
452 struct blk_trace *blk_trace;
455 * for flush operations
457 unsigned int flush_flags;
458 unsigned int flush_not_queueable:1;
459 struct blk_flush_queue *fq;
461 struct list_head requeue_list;
462 spinlock_t requeue_lock;
463 struct work_struct requeue_work;
465 struct mutex sysfs_lock;
470 #if defined(CONFIG_BLK_DEV_BSG)
471 bsg_job_fn *bsg_job_fn;
473 struct bsg_class_device bsg_dev;
476 #ifdef CONFIG_BLK_DEV_THROTTLING
478 struct throtl_data *td;
480 struct rcu_head rcu_head;
481 wait_queue_head_t mq_freeze_wq;
482 struct percpu_ref mq_usage_counter;
483 struct list_head all_q_node;
485 struct blk_mq_tag_set *tag_set;
486 struct list_head tag_set_list;
489 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
490 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
491 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
492 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
493 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
494 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
495 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
496 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
497 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
498 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
499 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
500 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
501 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
502 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
503 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
504 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
505 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
506 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
507 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
508 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
509 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
510 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
511 #define QUEUE_FLAG_SG_GAPS 22 /* queue doesn't support SG gaps */
513 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
514 (1 << QUEUE_FLAG_STACKABLE) | \
515 (1 << QUEUE_FLAG_SAME_COMP) | \
516 (1 << QUEUE_FLAG_ADD_RANDOM))
518 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
519 (1 << QUEUE_FLAG_SAME_COMP))
521 static inline void queue_lockdep_assert_held(struct request_queue *q)
524 lockdep_assert_held(q->queue_lock);
527 static inline void queue_flag_set_unlocked(unsigned int flag,
528 struct request_queue *q)
530 __set_bit(flag, &q->queue_flags);
533 static inline int queue_flag_test_and_clear(unsigned int flag,
534 struct request_queue *q)
536 queue_lockdep_assert_held(q);
538 if (test_bit(flag, &q->queue_flags)) {
539 __clear_bit(flag, &q->queue_flags);
546 static inline int queue_flag_test_and_set(unsigned int flag,
547 struct request_queue *q)
549 queue_lockdep_assert_held(q);
551 if (!test_bit(flag, &q->queue_flags)) {
552 __set_bit(flag, &q->queue_flags);
559 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
561 queue_lockdep_assert_held(q);
562 __set_bit(flag, &q->queue_flags);
565 static inline void queue_flag_clear_unlocked(unsigned int flag,
566 struct request_queue *q)
568 __clear_bit(flag, &q->queue_flags);
571 static inline int queue_in_flight(struct request_queue *q)
573 return q->in_flight[0] + q->in_flight[1];
576 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
578 queue_lockdep_assert_held(q);
579 __clear_bit(flag, &q->queue_flags);
582 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
583 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
584 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
585 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
586 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
587 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
588 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
589 #define blk_queue_noxmerges(q) \
590 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
591 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
592 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
593 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
594 #define blk_queue_stackable(q) \
595 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
596 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
597 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
598 test_bit(QUEUE_FLAG_SECDISCARD, &(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_pm_request(rq) \
609 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
610 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
612 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
613 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
614 /* rq->queuelist of dequeued request must be list_empty() */
615 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
617 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
619 #define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
622 * Driver can handle struct request, if it either has an old style
623 * request_fn defined, or is blk-mq based.
625 static inline bool queue_is_rq_based(struct request_queue *q)
627 return q->request_fn || q->mq_ops;
630 static inline unsigned int blk_queue_cluster(struct request_queue *q)
632 return q->limits.cluster;
636 * We regard a request as sync, if either a read or a sync write
638 static inline bool rw_is_sync(unsigned int rw_flags)
640 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
643 static inline bool rq_is_sync(struct request *rq)
645 return rw_is_sync(rq->cmd_flags);
648 static inline bool blk_rl_full(struct request_list *rl, bool sync)
650 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
652 return rl->flags & flag;
655 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
657 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
662 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
664 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
669 static inline bool rq_mergeable(struct request *rq)
671 if (rq->cmd_type != REQ_TYPE_FS)
674 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
680 static inline bool blk_check_merge_flags(unsigned int flags1,
683 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
686 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
689 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
695 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
697 if (bio_data(a) == bio_data(b))
704 * q->prep_rq_fn return values
706 #define BLKPREP_OK 0 /* serve it */
707 #define BLKPREP_KILL 1 /* fatal error, kill */
708 #define BLKPREP_DEFER 2 /* leave on queue */
710 extern unsigned long blk_max_low_pfn, blk_max_pfn;
713 * standard bounce addresses:
715 * BLK_BOUNCE_HIGH : bounce all highmem pages
716 * BLK_BOUNCE_ANY : don't bounce anything
717 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
720 #if BITS_PER_LONG == 32
721 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
723 #define BLK_BOUNCE_HIGH -1ULL
725 #define BLK_BOUNCE_ANY (-1ULL)
726 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
729 * default timeout for SG_IO if none specified
731 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
732 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
735 extern int init_emergency_isa_pool(void);
736 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
738 static inline int init_emergency_isa_pool(void)
742 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
745 #endif /* CONFIG_MMU */
751 unsigned long offset;
756 struct req_iterator {
757 struct bvec_iter iter;
761 /* This should not be used directly - use rq_for_each_segment */
762 #define for_each_bio(_bio) \
763 for (; _bio; _bio = _bio->bi_next)
764 #define __rq_for_each_bio(_bio, rq) \
766 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
768 #define rq_for_each_segment(bvl, _rq, _iter) \
769 __rq_for_each_bio(_iter.bio, _rq) \
770 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
772 #define rq_iter_last(bvec, _iter) \
773 (_iter.bio->bi_next == NULL && \
774 bio_iter_last(bvec, _iter.iter))
776 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
777 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
779 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
780 extern void rq_flush_dcache_pages(struct request *rq);
782 static inline void rq_flush_dcache_pages(struct request *rq)
787 extern int blk_register_queue(struct gendisk *disk);
788 extern void blk_unregister_queue(struct gendisk *disk);
789 extern void generic_make_request(struct bio *bio);
790 extern void blk_rq_init(struct request_queue *q, struct request *rq);
791 extern void blk_put_request(struct request *);
792 extern void __blk_put_request(struct request_queue *, struct request *);
793 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
794 extern struct request *blk_make_request(struct request_queue *, struct bio *,
796 extern void blk_rq_set_block_pc(struct request *);
797 extern void blk_requeue_request(struct request_queue *, struct request *);
798 extern void blk_add_request_payload(struct request *rq, struct page *page,
800 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
801 extern int blk_lld_busy(struct request_queue *q);
802 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
803 struct bio_set *bs, gfp_t gfp_mask,
804 int (*bio_ctr)(struct bio *, struct bio *, void *),
806 extern void blk_rq_unprep_clone(struct request *rq);
807 extern int blk_insert_cloned_request(struct request_queue *q,
809 extern void blk_delay_queue(struct request_queue *, unsigned long);
810 extern void blk_recount_segments(struct request_queue *, struct bio *);
811 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
812 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
813 unsigned int, void __user *);
814 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
815 unsigned int, void __user *);
816 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
817 struct scsi_ioctl_command __user *);
819 extern void blk_queue_bio(struct request_queue *q, struct bio *bio);
822 * A queue has just exitted congestion. Note this in the global counter of
823 * congested queues, and wake up anyone who was waiting for requests to be
826 static inline void blk_clear_queue_congested(struct request_queue *q, int sync)
828 clear_bdi_congested(&q->backing_dev_info, sync);
832 * A queue has just entered congestion. Flag that in the queue's VM-visible
833 * state flags and increment the global gounter of congested queues.
835 static inline void blk_set_queue_congested(struct request_queue *q, int sync)
837 set_bdi_congested(&q->backing_dev_info, sync);
840 extern void blk_start_queue(struct request_queue *q);
841 extern void blk_stop_queue(struct request_queue *q);
842 extern void blk_sync_queue(struct request_queue *q);
843 extern void __blk_stop_queue(struct request_queue *q);
844 extern void __blk_run_queue(struct request_queue *q);
845 extern void blk_run_queue(struct request_queue *);
846 extern void blk_run_queue_async(struct request_queue *q);
847 extern int blk_rq_map_user(struct request_queue *, struct request *,
848 struct rq_map_data *, void __user *, unsigned long,
850 extern int blk_rq_unmap_user(struct bio *);
851 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
852 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
853 struct rq_map_data *, const struct sg_iovec *,
854 int, unsigned int, gfp_t);
855 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
856 struct request *, int);
857 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
858 struct request *, int, rq_end_io_fn *);
860 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
862 return bdev->bd_disk->queue; /* this is never NULL */
866 * blk_rq_pos() : the current sector
867 * blk_rq_bytes() : bytes left in the entire request
868 * blk_rq_cur_bytes() : bytes left in the current segment
869 * blk_rq_err_bytes() : bytes left till the next error boundary
870 * blk_rq_sectors() : sectors left in the entire request
871 * blk_rq_cur_sectors() : sectors left in the current segment
873 static inline sector_t blk_rq_pos(const struct request *rq)
878 static inline unsigned int blk_rq_bytes(const struct request *rq)
880 return rq->__data_len;
883 static inline int blk_rq_cur_bytes(const struct request *rq)
885 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
888 extern unsigned int blk_rq_err_bytes(const struct request *rq);
890 static inline unsigned int blk_rq_sectors(const struct request *rq)
892 return blk_rq_bytes(rq) >> 9;
895 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
897 return blk_rq_cur_bytes(rq) >> 9;
900 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
901 unsigned int cmd_flags)
903 if (unlikely(cmd_flags & REQ_DISCARD))
904 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
906 if (unlikely(cmd_flags & REQ_WRITE_SAME))
907 return q->limits.max_write_same_sectors;
909 return q->limits.max_sectors;
913 * Return maximum size of a request at given offset. Only valid for
914 * file system requests.
916 static inline unsigned int blk_max_size_offset(struct request_queue *q,
919 if (!q->limits.chunk_sectors)
920 return q->limits.max_sectors;
922 return q->limits.chunk_sectors -
923 (offset & (q->limits.chunk_sectors - 1));
926 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
928 struct request_queue *q = rq->q;
930 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
931 return q->limits.max_hw_sectors;
933 if (!q->limits.chunk_sectors)
934 return blk_queue_get_max_sectors(q, rq->cmd_flags);
936 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
937 blk_queue_get_max_sectors(q, rq->cmd_flags));
940 static inline unsigned int blk_rq_count_bios(struct request *rq)
942 unsigned int nr_bios = 0;
945 __rq_for_each_bio(bio, rq)
952 * Request issue related functions.
954 extern struct request *blk_peek_request(struct request_queue *q);
955 extern void blk_start_request(struct request *rq);
956 extern struct request *blk_fetch_request(struct request_queue *q);
959 * Request completion related functions.
961 * blk_update_request() completes given number of bytes and updates
962 * the request without completing it.
964 * blk_end_request() and friends. __blk_end_request() must be called
965 * with the request queue spinlock acquired.
967 * Several drivers define their own end_request and call
968 * blk_end_request() for parts of the original function.
969 * This prevents code duplication in drivers.
971 extern bool blk_update_request(struct request *rq, int error,
972 unsigned int nr_bytes);
973 extern void blk_finish_request(struct request *rq, int error);
974 extern bool blk_end_request(struct request *rq, int error,
975 unsigned int nr_bytes);
976 extern void blk_end_request_all(struct request *rq, int error);
977 extern bool blk_end_request_cur(struct request *rq, int error);
978 extern bool blk_end_request_err(struct request *rq, int error);
979 extern bool __blk_end_request(struct request *rq, int error,
980 unsigned int nr_bytes);
981 extern void __blk_end_request_all(struct request *rq, int error);
982 extern bool __blk_end_request_cur(struct request *rq, int error);
983 extern bool __blk_end_request_err(struct request *rq, int error);
985 extern void blk_complete_request(struct request *);
986 extern void __blk_complete_request(struct request *);
987 extern void blk_abort_request(struct request *);
988 extern void blk_unprep_request(struct request *);
991 * Access functions for manipulating queue properties
993 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
994 spinlock_t *lock, int node_id);
995 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
996 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
997 request_fn_proc *, spinlock_t *);
998 extern void blk_cleanup_queue(struct request_queue *);
999 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1000 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1001 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
1002 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1003 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1004 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1005 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1006 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1007 unsigned int max_discard_sectors);
1008 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1009 unsigned int max_write_same_sectors);
1010 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
1011 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1012 extern void blk_queue_alignment_offset(struct request_queue *q,
1013 unsigned int alignment);
1014 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1015 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1016 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1017 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1018 extern void blk_set_default_limits(struct queue_limits *lim);
1019 extern void blk_set_stacking_limits(struct queue_limits *lim);
1020 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1022 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1024 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1026 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1027 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1028 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1029 extern int blk_queue_dma_drain(struct request_queue *q,
1030 dma_drain_needed_fn *dma_drain_needed,
1031 void *buf, unsigned int size);
1032 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1033 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1034 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1035 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1036 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
1037 extern void blk_queue_dma_alignment(struct request_queue *, int);
1038 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1039 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1040 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1041 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1042 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
1043 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1044 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1046 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1047 extern int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
1048 struct scatterlist *sglist);
1049 extern void blk_dump_rq_flags(struct request *, char *);
1050 extern long nr_blockdev_pages(void);
1052 bool __must_check blk_get_queue(struct request_queue *);
1053 struct request_queue *blk_alloc_queue(gfp_t);
1054 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1055 extern void blk_put_queue(struct request_queue *);
1058 * block layer runtime pm functions
1060 #ifdef CONFIG_PM_RUNTIME
1061 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1062 extern int blk_pre_runtime_suspend(struct request_queue *q);
1063 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1064 extern void blk_pre_runtime_resume(struct request_queue *q);
1065 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1067 static inline void blk_pm_runtime_init(struct request_queue *q,
1068 struct device *dev) {}
1069 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1073 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1074 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1075 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1079 * blk_plug permits building a queue of related requests by holding the I/O
1080 * fragments for a short period. This allows merging of sequential requests
1081 * into single larger request. As the requests are moved from a per-task list to
1082 * the device's request_queue in a batch, this results in improved scalability
1083 * as the lock contention for request_queue lock is reduced.
1085 * It is ok not to disable preemption when adding the request to the plug list
1086 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1087 * the plug list when the task sleeps by itself. For details, please see
1088 * schedule() where blk_schedule_flush_plug() is called.
1091 struct list_head list; /* requests */
1092 struct list_head mq_list; /* blk-mq requests */
1093 struct list_head cb_list; /* md requires an unplug callback */
1095 #define BLK_MAX_REQUEST_COUNT 16
1098 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1099 struct blk_plug_cb {
1100 struct list_head list;
1101 blk_plug_cb_fn callback;
1104 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1105 void *data, int size);
1106 extern void blk_start_plug(struct blk_plug *);
1107 extern void blk_finish_plug(struct blk_plug *);
1108 extern void blk_flush_plug_list(struct blk_plug *, bool);
1110 static inline void blk_flush_plug(struct task_struct *tsk)
1112 struct blk_plug *plug = tsk->plug;
1115 blk_flush_plug_list(plug, false);
1118 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1120 struct blk_plug *plug = tsk->plug;
1123 blk_flush_plug_list(plug, true);
1126 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1128 struct blk_plug *plug = tsk->plug;
1131 (!list_empty(&plug->list) ||
1132 !list_empty(&plug->mq_list) ||
1133 !list_empty(&plug->cb_list));
1139 #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED)
1140 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1141 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1142 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1143 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
1144 extern void blk_queue_free_tags(struct request_queue *);
1145 extern int blk_queue_resize_tags(struct request_queue *, int);
1146 extern void blk_queue_invalidate_tags(struct request_queue *);
1147 extern struct blk_queue_tag *blk_init_tags(int);
1148 extern void blk_free_tags(struct blk_queue_tag *);
1150 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1153 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1155 return bqt->tag_index[tag];
1158 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1160 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1161 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1162 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1163 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1164 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1165 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1166 sector_t nr_sects, gfp_t gfp_mask);
1167 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1168 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1170 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1171 nr_blocks << (sb->s_blocksize_bits - 9),
1174 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1175 sector_t nr_blocks, gfp_t gfp_mask)
1177 return blkdev_issue_zeroout(sb->s_bdev,
1178 block << (sb->s_blocksize_bits - 9),
1179 nr_blocks << (sb->s_blocksize_bits - 9),
1183 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1185 enum blk_default_limits {
1186 BLK_MAX_SEGMENTS = 128,
1187 BLK_SAFE_MAX_SECTORS = 255,
1188 BLK_DEF_MAX_SECTORS = 1024,
1189 BLK_MAX_SEGMENT_SIZE = 65536,
1190 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1193 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1195 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1197 return q->limits.bounce_pfn;
1200 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1202 return q->limits.seg_boundary_mask;
1205 static inline unsigned int queue_max_sectors(struct request_queue *q)
1207 return q->limits.max_sectors;
1210 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1212 return q->limits.max_hw_sectors;
1215 static inline unsigned short queue_max_segments(struct request_queue *q)
1217 return q->limits.max_segments;
1220 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1222 return q->limits.max_segment_size;
1225 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1229 if (q && q->limits.logical_block_size)
1230 retval = q->limits.logical_block_size;
1235 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1237 return queue_logical_block_size(bdev_get_queue(bdev));
1240 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1242 return q->limits.physical_block_size;
1245 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1247 return queue_physical_block_size(bdev_get_queue(bdev));
1250 static inline unsigned int queue_io_min(struct request_queue *q)
1252 return q->limits.io_min;
1255 static inline int bdev_io_min(struct block_device *bdev)
1257 return queue_io_min(bdev_get_queue(bdev));
1260 static inline unsigned int queue_io_opt(struct request_queue *q)
1262 return q->limits.io_opt;
1265 static inline int bdev_io_opt(struct block_device *bdev)
1267 return queue_io_opt(bdev_get_queue(bdev));
1270 static inline int queue_alignment_offset(struct request_queue *q)
1272 if (q->limits.misaligned)
1275 return q->limits.alignment_offset;
1278 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1280 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1281 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1283 return (granularity + lim->alignment_offset - alignment) % granularity;
1286 static inline int bdev_alignment_offset(struct block_device *bdev)
1288 struct request_queue *q = bdev_get_queue(bdev);
1290 if (q->limits.misaligned)
1293 if (bdev != bdev->bd_contains)
1294 return bdev->bd_part->alignment_offset;
1296 return q->limits.alignment_offset;
1299 static inline int queue_discard_alignment(struct request_queue *q)
1301 if (q->limits.discard_misaligned)
1304 return q->limits.discard_alignment;
1307 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1309 unsigned int alignment, granularity, offset;
1311 if (!lim->max_discard_sectors)
1314 /* Why are these in bytes, not sectors? */
1315 alignment = lim->discard_alignment >> 9;
1316 granularity = lim->discard_granularity >> 9;
1320 /* Offset of the partition start in 'granularity' sectors */
1321 offset = sector_div(sector, granularity);
1323 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1324 offset = (granularity + alignment - offset) % granularity;
1326 /* Turn it back into bytes, gaah */
1330 static inline int bdev_discard_alignment(struct block_device *bdev)
1332 struct request_queue *q = bdev_get_queue(bdev);
1334 if (bdev != bdev->bd_contains)
1335 return bdev->bd_part->discard_alignment;
1337 return q->limits.discard_alignment;
1340 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1342 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1348 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1350 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1353 static inline unsigned int bdev_write_same(struct block_device *bdev)
1355 struct request_queue *q = bdev_get_queue(bdev);
1358 return q->limits.max_write_same_sectors;
1363 static inline int queue_dma_alignment(struct request_queue *q)
1365 return q ? q->dma_alignment : 511;
1368 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1371 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1372 return !(addr & alignment) && !(len & alignment);
1375 /* assumes size > 256 */
1376 static inline unsigned int blksize_bits(unsigned int size)
1378 unsigned int bits = 8;
1382 } while (size > 256);
1386 static inline unsigned int block_size(struct block_device *bdev)
1388 return bdev->bd_block_size;
1391 static inline bool queue_flush_queueable(struct request_queue *q)
1393 return !q->flush_not_queueable;
1396 typedef struct {struct page *v;} Sector;
1398 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1400 static inline void put_dev_sector(Sector p)
1402 page_cache_release(p.v);
1406 int kblockd_schedule_work(struct work_struct *work);
1407 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1408 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1410 #ifdef CONFIG_BLK_CGROUP
1412 * This should not be using sched_clock(). A real patch is in progress
1413 * to fix this up, until that is in place we need to disable preemption
1414 * around sched_clock() in this function and set_io_start_time_ns().
1416 static inline void set_start_time_ns(struct request *req)
1419 req->start_time_ns = sched_clock();
1423 static inline void set_io_start_time_ns(struct request *req)
1426 req->io_start_time_ns = sched_clock();
1430 static inline uint64_t rq_start_time_ns(struct request *req)
1432 return req->start_time_ns;
1435 static inline uint64_t rq_io_start_time_ns(struct request *req)
1437 return req->io_start_time_ns;
1440 static inline void set_start_time_ns(struct request *req) {}
1441 static inline void set_io_start_time_ns(struct request *req) {}
1442 static inline uint64_t rq_start_time_ns(struct request *req)
1446 static inline uint64_t rq_io_start_time_ns(struct request *req)
1452 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1453 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1454 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1455 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1457 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1459 enum blk_integrity_flags {
1460 BLK_INTEGRITY_VERIFY = 1 << 0,
1461 BLK_INTEGRITY_GENERATE = 1 << 1,
1462 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1463 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1466 struct blk_integrity_iter {
1470 unsigned int data_size;
1471 unsigned short interval;
1472 const char *disk_name;
1475 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1477 struct blk_integrity {
1478 integrity_processing_fn *generate_fn;
1479 integrity_processing_fn *verify_fn;
1481 unsigned short flags;
1482 unsigned short tuple_size;
1483 unsigned short interval;
1484 unsigned short tag_size;
1488 struct kobject kobj;
1491 extern bool blk_integrity_is_initialized(struct gendisk *);
1492 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1493 extern void blk_integrity_unregister(struct gendisk *);
1494 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1495 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1496 struct scatterlist *);
1497 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1498 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1500 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1504 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1506 return bdev->bd_disk->integrity;
1509 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1511 return disk->integrity;
1514 static inline bool blk_integrity_rq(struct request *rq)
1516 return rq->cmd_flags & REQ_INTEGRITY;
1519 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1522 q->limits.max_integrity_segments = segs;
1525 static inline unsigned short
1526 queue_max_integrity_segments(struct request_queue *q)
1528 return q->limits.max_integrity_segments;
1531 #else /* CONFIG_BLK_DEV_INTEGRITY */
1534 struct block_device;
1536 struct blk_integrity;
1538 static inline int blk_integrity_rq(struct request *rq)
1542 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1547 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1549 struct scatterlist *s)
1553 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1557 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1561 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1565 static inline int blk_integrity_register(struct gendisk *d,
1566 struct blk_integrity *b)
1570 static inline void blk_integrity_unregister(struct gendisk *d)
1573 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1577 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1581 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1587 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1593 static inline bool blk_integrity_is_initialized(struct gendisk *g)
1598 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1600 struct block_device_operations {
1601 int (*open) (struct block_device *, fmode_t);
1602 void (*release) (struct gendisk *, fmode_t);
1603 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1604 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1605 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1606 int (*direct_access) (struct block_device *, sector_t,
1607 void **, unsigned long *);
1608 unsigned int (*check_events) (struct gendisk *disk,
1609 unsigned int clearing);
1610 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1611 int (*media_changed) (struct gendisk *);
1612 void (*unlock_native_capacity) (struct gendisk *);
1613 int (*revalidate_disk) (struct gendisk *);
1614 int (*getgeo)(struct block_device *, struct hd_geometry *);
1615 /* this callback is with swap_lock and sometimes page table lock held */
1616 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1617 struct module *owner;
1620 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1622 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1623 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1624 struct writeback_control *);
1625 #else /* CONFIG_BLOCK */
1627 struct block_device;
1630 * stubs for when the block layer is configured out
1632 #define buffer_heads_over_limit 0
1634 static inline long nr_blockdev_pages(void)
1642 static inline void blk_start_plug(struct blk_plug *plug)
1646 static inline void blk_finish_plug(struct blk_plug *plug)
1650 static inline void blk_flush_plug(struct task_struct *task)
1654 static inline void blk_schedule_flush_plug(struct task_struct *task)
1659 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1664 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1665 sector_t *error_sector)
1670 #endif /* CONFIG_BLOCK */