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>
25 #include <asm/scatterlist.h>
28 struct scsi_ioctl_command;
31 struct elevator_queue;
32 struct request_pm_state;
39 #define BLKDEV_MIN_RQ 4
40 #define BLKDEV_MAX_RQ 128 /* Default maximum */
43 * Maximum number of blkcg policies allowed to be registered concurrently.
44 * Defined here to simplify include dependency.
46 #define BLKCG_MAX_POLS 2
49 typedef void (rq_end_io_fn)(struct request *, int);
51 #define BLK_RL_SYNCFULL (1U << 0)
52 #define BLK_RL_ASYNCFULL (1U << 1)
55 struct request_queue *q; /* the queue this rl belongs to */
56 #ifdef CONFIG_BLK_CGROUP
57 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
60 * count[], starved[], and wait[] are indexed by
61 * BLK_RW_SYNC/BLK_RW_ASYNC
66 wait_queue_head_t wait[2];
71 * request command types
73 enum rq_cmd_type_bits {
74 REQ_TYPE_FS = 1, /* fs request */
75 REQ_TYPE_BLOCK_PC, /* scsi command */
76 REQ_TYPE_SENSE, /* sense request */
77 REQ_TYPE_PM_SUSPEND, /* suspend request */
78 REQ_TYPE_PM_RESUME, /* resume request */
79 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */
80 REQ_TYPE_SPECIAL, /* driver defined type */
82 * for ATA/ATAPI devices. this really doesn't belong here, ide should
83 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
84 * private REQ_LB opcodes to differentiate what type of request this is
86 REQ_TYPE_ATA_TASKFILE,
90 #define BLK_MAX_CDB 16
93 * Try to put the fields that are referenced together in the same cacheline.
95 * If you modify this structure, make sure to update blk_rq_init() and
96 * especially blk_mq_rq_ctx_init() to take care of the added fields.
99 struct list_head queuelist;
101 struct call_single_data csd;
102 struct work_struct requeue_work;
103 unsigned long fifo_time;
106 struct request_queue *q;
107 struct blk_mq_ctx *mq_ctx;
110 enum rq_cmd_type_bits cmd_type;
111 unsigned long atomic_flags;
115 /* the following two fields are internal, NEVER access directly */
116 unsigned int __data_len; /* total data len */
117 sector_t __sector; /* sector cursor */
123 * The hash is used inside the scheduler, and killed once the
124 * request reaches the dispatch list. The ipi_list is only used
125 * to queue the request for softirq completion, which is long
126 * after the request has been unhashed (and even removed from
127 * the dispatch list).
130 struct hlist_node hash; /* merge hash */
131 struct list_head ipi_list;
135 * The rb_node is only used inside the io scheduler, requests
136 * are pruned when moved to the dispatch queue. So let the
137 * completion_data share space with the rb_node.
140 struct rb_node rb_node; /* sort/lookup */
141 void *completion_data;
145 * Three pointers are available for the IO schedulers, if they need
146 * more they have to dynamically allocate it. Flush requests are
147 * never put on the IO scheduler. So let the flush fields share
148 * space with the elevator data.
158 struct list_head list;
159 rq_end_io_fn *saved_end_io;
163 struct gendisk *rq_disk;
164 struct hd_struct *part;
165 unsigned long start_time;
166 #ifdef CONFIG_BLK_CGROUP
167 struct request_list *rl; /* rl this rq is alloced from */
168 unsigned long long start_time_ns;
169 unsigned long long io_start_time_ns; /* when passed to hardware */
171 /* Number of scatter-gather DMA addr+len pairs after
172 * physical address coalescing is performed.
174 unsigned short nr_phys_segments;
175 #if defined(CONFIG_BLK_DEV_INTEGRITY)
176 unsigned short nr_integrity_segments;
179 unsigned short ioprio;
181 void *special; /* opaque pointer available for LLD use */
187 * when request is used as a packet command carrier
189 unsigned char __cmd[BLK_MAX_CDB];
191 unsigned short cmd_len;
193 unsigned int extra_len; /* length of alignment and padding */
194 unsigned int sense_len;
195 unsigned int resid_len; /* residual count */
198 unsigned long deadline;
199 struct list_head timeout_list;
200 unsigned int timeout;
204 * completion callback.
206 rq_end_io_fn *end_io;
210 struct request *next_rq;
213 static inline unsigned short req_get_ioprio(struct request *req)
219 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
220 * requests. Some step values could eventually be made generic.
222 struct request_pm_state
224 /* PM state machine step value, currently driver specific */
226 /* requested PM state value (S1, S2, S3, S4, ...) */
228 void* data; /* for driver use */
231 #include <linux/elevator.h>
233 struct blk_queue_ctx;
235 typedef void (request_fn_proc) (struct request_queue *q);
236 typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
237 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
238 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
241 struct bvec_merge_data {
242 struct block_device *bi_bdev;
247 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
249 typedef void (softirq_done_fn)(struct request *);
250 typedef int (dma_drain_needed_fn)(struct request *);
251 typedef int (lld_busy_fn) (struct request_queue *q);
252 typedef int (bsg_job_fn) (struct bsg_job *);
254 enum blk_eh_timer_return {
260 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
262 enum blk_queue_state {
267 struct blk_queue_tag {
268 struct request **tag_index; /* map of busy tags */
269 unsigned long *tag_map; /* bit map of free/busy tags */
270 int busy; /* current depth */
271 int max_depth; /* what we will send to device */
272 int real_max_depth; /* what the array can hold */
273 atomic_t refcnt; /* map can be shared */
276 #define BLK_SCSI_MAX_CMDS (256)
277 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
279 struct queue_limits {
280 unsigned long bounce_pfn;
281 unsigned long seg_boundary_mask;
283 unsigned int max_hw_sectors;
284 unsigned int max_sectors;
285 unsigned int max_segment_size;
286 unsigned int physical_block_size;
287 unsigned int alignment_offset;
290 unsigned int max_discard_sectors;
291 unsigned int max_write_same_sectors;
292 unsigned int discard_granularity;
293 unsigned int discard_alignment;
295 unsigned short logical_block_size;
296 unsigned short max_segments;
297 unsigned short max_integrity_segments;
299 unsigned char misaligned;
300 unsigned char discard_misaligned;
301 unsigned char cluster;
302 unsigned char discard_zeroes_data;
303 unsigned char raid_partial_stripes_expensive;
306 struct request_queue {
308 * Together with queue_head for cacheline sharing
310 struct list_head queue_head;
311 struct request *last_merge;
312 struct elevator_queue *elevator;
313 int nr_rqs[2]; /* # allocated [a]sync rqs */
314 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
317 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
318 * is used, root blkg allocates from @q->root_rl and all other
319 * blkgs from their own blkg->rl. Which one to use should be
320 * determined using bio_request_list().
322 struct request_list root_rl;
324 request_fn_proc *request_fn;
325 make_request_fn *make_request_fn;
326 prep_rq_fn *prep_rq_fn;
327 unprep_rq_fn *unprep_rq_fn;
328 merge_bvec_fn *merge_bvec_fn;
329 softirq_done_fn *softirq_done_fn;
330 rq_timed_out_fn *rq_timed_out_fn;
331 dma_drain_needed_fn *dma_drain_needed;
332 lld_busy_fn *lld_busy_fn;
334 struct blk_mq_ops *mq_ops;
336 unsigned int *mq_map;
339 struct blk_mq_ctx *queue_ctx;
340 unsigned int nr_queues;
342 /* hw dispatch queues */
343 struct blk_mq_hw_ctx **queue_hw_ctx;
344 unsigned int nr_hw_queues;
347 * Dispatch queue sorting
350 struct request *boundary_rq;
353 * Delayed queue handling
355 struct delayed_work delay_work;
357 struct backing_dev_info backing_dev_info;
360 * The queue owner gets to use this for whatever they like.
361 * ll_rw_blk doesn't touch it.
366 * various queue flags, see QUEUE_* below
368 unsigned long queue_flags;
371 * ida allocated id for this queue. Used to index queues from
377 * queue needs bounce pages for pages above this limit
382 * protects queue structures from reentrancy. ->__queue_lock should
383 * _never_ be used directly, it is queue private. always use
386 spinlock_t __queue_lock;
387 spinlock_t *queue_lock;
397 struct kobject mq_kobj;
399 #ifdef CONFIG_PM_RUNTIME
402 unsigned int nr_pending;
408 unsigned long nr_requests; /* Max # of requests */
409 unsigned int nr_congestion_on;
410 unsigned int nr_congestion_off;
411 unsigned int nr_batching;
413 unsigned int dma_drain_size;
414 void *dma_drain_buffer;
415 unsigned int dma_pad_mask;
416 unsigned int dma_alignment;
418 struct blk_queue_tag *queue_tags;
419 struct list_head tag_busy_list;
421 unsigned int nr_sorted;
422 unsigned int in_flight[2];
424 * Number of active block driver functions for which blk_drain_queue()
425 * must wait. Must be incremented around functions that unlock the
426 * queue_lock internally, e.g. scsi_request_fn().
428 unsigned int request_fn_active;
430 unsigned int rq_timeout;
431 struct timer_list timeout;
432 struct list_head timeout_list;
434 struct list_head icq_list;
435 #ifdef CONFIG_BLK_CGROUP
436 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
437 struct blkcg_gq *root_blkg;
438 struct list_head blkg_list;
441 struct queue_limits limits;
446 unsigned int sg_timeout;
447 unsigned int sg_reserved_size;
449 #ifdef CONFIG_BLK_DEV_IO_TRACE
450 struct blk_trace *blk_trace;
453 * for flush operations
455 unsigned int flush_flags;
456 unsigned int flush_not_queueable:1;
457 unsigned int flush_queue_delayed:1;
458 unsigned int flush_pending_idx:1;
459 unsigned int flush_running_idx:1;
460 unsigned long flush_pending_since;
461 struct list_head flush_queue[2];
462 struct list_head flush_data_in_flight;
463 struct request *flush_rq;
464 spinlock_t mq_flush_lock;
466 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_counter 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 */
511 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
512 (1 << QUEUE_FLAG_STACKABLE) | \
513 (1 << QUEUE_FLAG_SAME_COMP) | \
514 (1 << QUEUE_FLAG_ADD_RANDOM))
516 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
517 (1 << QUEUE_FLAG_SAME_COMP))
519 static inline void queue_lockdep_assert_held(struct request_queue *q)
522 lockdep_assert_held(q->queue_lock);
525 static inline void queue_flag_set_unlocked(unsigned int flag,
526 struct request_queue *q)
528 __set_bit(flag, &q->queue_flags);
531 static inline int queue_flag_test_and_clear(unsigned int flag,
532 struct request_queue *q)
534 queue_lockdep_assert_held(q);
536 if (test_bit(flag, &q->queue_flags)) {
537 __clear_bit(flag, &q->queue_flags);
544 static inline int queue_flag_test_and_set(unsigned int flag,
545 struct request_queue *q)
547 queue_lockdep_assert_held(q);
549 if (!test_bit(flag, &q->queue_flags)) {
550 __set_bit(flag, &q->queue_flags);
557 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
559 queue_lockdep_assert_held(q);
560 __set_bit(flag, &q->queue_flags);
563 static inline void queue_flag_clear_unlocked(unsigned int flag,
564 struct request_queue *q)
566 __clear_bit(flag, &q->queue_flags);
569 static inline int queue_in_flight(struct request_queue *q)
571 return q->in_flight[0] + q->in_flight[1];
574 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
576 queue_lockdep_assert_held(q);
577 __clear_bit(flag, &q->queue_flags);
580 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
581 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
582 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
583 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
584 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
585 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
586 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
587 #define blk_queue_noxmerges(q) \
588 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
589 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
590 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
591 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
592 #define blk_queue_stackable(q) \
593 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
594 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
595 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
596 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
598 #define blk_noretry_request(rq) \
599 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
600 REQ_FAILFAST_DRIVER))
602 #define blk_account_rq(rq) \
603 (((rq)->cmd_flags & REQ_STARTED) && \
604 ((rq)->cmd_type == REQ_TYPE_FS))
606 #define blk_pm_request(rq) \
607 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
608 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
610 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
611 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
612 /* rq->queuelist of dequeued request must be list_empty() */
613 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
615 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
617 #define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
619 static inline unsigned int blk_queue_cluster(struct request_queue *q)
621 return q->limits.cluster;
625 * We regard a request as sync, if either a read or a sync write
627 static inline bool rw_is_sync(unsigned int rw_flags)
629 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
632 static inline bool rq_is_sync(struct request *rq)
634 return rw_is_sync(rq->cmd_flags);
637 static inline bool blk_rl_full(struct request_list *rl, bool sync)
639 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
641 return rl->flags & flag;
644 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
646 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
651 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
653 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
658 static inline bool rq_mergeable(struct request *rq)
660 if (rq->cmd_type != REQ_TYPE_FS)
663 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
669 static inline bool blk_check_merge_flags(unsigned int flags1,
672 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
675 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
678 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
684 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
686 if (bio_data(a) == bio_data(b))
693 * q->prep_rq_fn return values
695 #define BLKPREP_OK 0 /* serve it */
696 #define BLKPREP_KILL 1 /* fatal error, kill */
697 #define BLKPREP_DEFER 2 /* leave on queue */
699 extern unsigned long blk_max_low_pfn, blk_max_pfn;
702 * standard bounce addresses:
704 * BLK_BOUNCE_HIGH : bounce all highmem pages
705 * BLK_BOUNCE_ANY : don't bounce anything
706 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
709 #if BITS_PER_LONG == 32
710 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
712 #define BLK_BOUNCE_HIGH -1ULL
714 #define BLK_BOUNCE_ANY (-1ULL)
715 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
718 * default timeout for SG_IO if none specified
720 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
721 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
724 extern int init_emergency_isa_pool(void);
725 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
727 static inline int init_emergency_isa_pool(void)
731 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
734 #endif /* CONFIG_MMU */
740 unsigned long offset;
745 struct req_iterator {
746 struct bvec_iter iter;
750 /* This should not be used directly - use rq_for_each_segment */
751 #define for_each_bio(_bio) \
752 for (; _bio; _bio = _bio->bi_next)
753 #define __rq_for_each_bio(_bio, rq) \
755 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
757 #define rq_for_each_segment(bvl, _rq, _iter) \
758 __rq_for_each_bio(_iter.bio, _rq) \
759 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
761 #define rq_iter_last(bvec, _iter) \
762 (_iter.bio->bi_next == NULL && \
763 bio_iter_last(bvec, _iter.iter))
765 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
766 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
768 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
769 extern void rq_flush_dcache_pages(struct request *rq);
771 static inline void rq_flush_dcache_pages(struct request *rq)
776 extern int blk_register_queue(struct gendisk *disk);
777 extern void blk_unregister_queue(struct gendisk *disk);
778 extern void generic_make_request(struct bio *bio);
779 extern void blk_rq_init(struct request_queue *q, struct request *rq);
780 extern void blk_put_request(struct request *);
781 extern void __blk_put_request(struct request_queue *, struct request *);
782 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
783 extern struct request *blk_make_request(struct request_queue *, struct bio *,
785 extern void blk_requeue_request(struct request_queue *, struct request *);
786 extern void blk_add_request_payload(struct request *rq, struct page *page,
788 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
789 extern int blk_lld_busy(struct request_queue *q);
790 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
791 struct bio_set *bs, gfp_t gfp_mask,
792 int (*bio_ctr)(struct bio *, struct bio *, void *),
794 extern void blk_rq_unprep_clone(struct request *rq);
795 extern int blk_insert_cloned_request(struct request_queue *q,
797 extern void blk_delay_queue(struct request_queue *, unsigned long);
798 extern void blk_recount_segments(struct request_queue *, struct bio *);
799 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
800 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
801 unsigned int, void __user *);
802 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
803 unsigned int, void __user *);
804 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
805 struct scsi_ioctl_command __user *);
807 extern void blk_queue_bio(struct request_queue *q, struct bio *bio);
810 * A queue has just exitted congestion. Note this in the global counter of
811 * congested queues, and wake up anyone who was waiting for requests to be
814 static inline void blk_clear_queue_congested(struct request_queue *q, int sync)
816 clear_bdi_congested(&q->backing_dev_info, sync);
820 * A queue has just entered congestion. Flag that in the queue's VM-visible
821 * state flags and increment the global gounter of congested queues.
823 static inline void blk_set_queue_congested(struct request_queue *q, int sync)
825 set_bdi_congested(&q->backing_dev_info, sync);
828 extern void blk_start_queue(struct request_queue *q);
829 extern void blk_stop_queue(struct request_queue *q);
830 extern void blk_sync_queue(struct request_queue *q);
831 extern void __blk_stop_queue(struct request_queue *q);
832 extern void __blk_run_queue(struct request_queue *q);
833 extern void blk_run_queue(struct request_queue *);
834 extern void blk_run_queue_async(struct request_queue *q);
835 extern int blk_rq_map_user(struct request_queue *, struct request *,
836 struct rq_map_data *, void __user *, unsigned long,
838 extern int blk_rq_unmap_user(struct bio *);
839 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
840 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
841 struct rq_map_data *, const struct sg_iovec *,
842 int, unsigned int, gfp_t);
843 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
844 struct request *, int);
845 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
846 struct request *, int, rq_end_io_fn *);
848 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
850 return bdev->bd_disk->queue;
854 * blk_rq_pos() : the current sector
855 * blk_rq_bytes() : bytes left in the entire request
856 * blk_rq_cur_bytes() : bytes left in the current segment
857 * blk_rq_err_bytes() : bytes left till the next error boundary
858 * blk_rq_sectors() : sectors left in the entire request
859 * blk_rq_cur_sectors() : sectors left in the current segment
861 static inline sector_t blk_rq_pos(const struct request *rq)
866 static inline unsigned int blk_rq_bytes(const struct request *rq)
868 return rq->__data_len;
871 static inline int blk_rq_cur_bytes(const struct request *rq)
873 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
876 extern unsigned int blk_rq_err_bytes(const struct request *rq);
878 static inline unsigned int blk_rq_sectors(const struct request *rq)
880 return blk_rq_bytes(rq) >> 9;
883 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
885 return blk_rq_cur_bytes(rq) >> 9;
888 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
889 unsigned int cmd_flags)
891 if (unlikely(cmd_flags & REQ_DISCARD))
892 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
894 if (unlikely(cmd_flags & REQ_WRITE_SAME))
895 return q->limits.max_write_same_sectors;
897 return q->limits.max_sectors;
900 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
902 struct request_queue *q = rq->q;
904 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
905 return q->limits.max_hw_sectors;
907 return blk_queue_get_max_sectors(q, rq->cmd_flags);
910 static inline unsigned int blk_rq_count_bios(struct request *rq)
912 unsigned int nr_bios = 0;
915 __rq_for_each_bio(bio, rq)
922 * Request issue related functions.
924 extern struct request *blk_peek_request(struct request_queue *q);
925 extern void blk_start_request(struct request *rq);
926 extern struct request *blk_fetch_request(struct request_queue *q);
929 * Request completion related functions.
931 * blk_update_request() completes given number of bytes and updates
932 * the request without completing it.
934 * blk_end_request() and friends. __blk_end_request() must be called
935 * with the request queue spinlock acquired.
937 * Several drivers define their own end_request and call
938 * blk_end_request() for parts of the original function.
939 * This prevents code duplication in drivers.
941 extern bool blk_update_request(struct request *rq, int error,
942 unsigned int nr_bytes);
943 extern void blk_finish_request(struct request *rq, int error);
944 extern bool blk_end_request(struct request *rq, int error,
945 unsigned int nr_bytes);
946 extern void blk_end_request_all(struct request *rq, int error);
947 extern bool blk_end_request_cur(struct request *rq, int error);
948 extern bool blk_end_request_err(struct request *rq, int error);
949 extern bool __blk_end_request(struct request *rq, int error,
950 unsigned int nr_bytes);
951 extern void __blk_end_request_all(struct request *rq, int error);
952 extern bool __blk_end_request_cur(struct request *rq, int error);
953 extern bool __blk_end_request_err(struct request *rq, int error);
955 extern void blk_complete_request(struct request *);
956 extern void __blk_complete_request(struct request *);
957 extern void blk_abort_request(struct request *);
958 extern void blk_unprep_request(struct request *);
961 * Access functions for manipulating queue properties
963 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
964 spinlock_t *lock, int node_id);
965 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
966 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
967 request_fn_proc *, spinlock_t *);
968 extern void blk_cleanup_queue(struct request_queue *);
969 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
970 extern void blk_queue_bounce_limit(struct request_queue *, u64);
971 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
972 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
973 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
974 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
975 extern void blk_queue_max_discard_sectors(struct request_queue *q,
976 unsigned int max_discard_sectors);
977 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
978 unsigned int max_write_same_sectors);
979 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
980 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
981 extern void blk_queue_alignment_offset(struct request_queue *q,
982 unsigned int alignment);
983 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
984 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
985 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
986 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
987 extern void blk_set_default_limits(struct queue_limits *lim);
988 extern void blk_set_stacking_limits(struct queue_limits *lim);
989 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
991 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
993 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
995 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
996 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
997 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
998 extern int blk_queue_dma_drain(struct request_queue *q,
999 dma_drain_needed_fn *dma_drain_needed,
1000 void *buf, unsigned int size);
1001 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1002 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1003 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1004 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1005 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
1006 extern void blk_queue_dma_alignment(struct request_queue *, int);
1007 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1008 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1009 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1010 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1011 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
1012 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1013 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1015 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1016 extern int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
1017 struct scatterlist *sglist);
1018 extern void blk_dump_rq_flags(struct request *, char *);
1019 extern long nr_blockdev_pages(void);
1021 bool __must_check blk_get_queue(struct request_queue *);
1022 struct request_queue *blk_alloc_queue(gfp_t);
1023 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1024 extern void blk_put_queue(struct request_queue *);
1027 * block layer runtime pm functions
1029 #ifdef CONFIG_PM_RUNTIME
1030 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1031 extern int blk_pre_runtime_suspend(struct request_queue *q);
1032 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1033 extern void blk_pre_runtime_resume(struct request_queue *q);
1034 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1036 static inline void blk_pm_runtime_init(struct request_queue *q,
1037 struct device *dev) {}
1038 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1042 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1043 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1044 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1048 * blk_plug permits building a queue of related requests by holding the I/O
1049 * fragments for a short period. This allows merging of sequential requests
1050 * into single larger request. As the requests are moved from a per-task list to
1051 * the device's request_queue in a batch, this results in improved scalability
1052 * as the lock contention for request_queue lock is reduced.
1054 * It is ok not to disable preemption when adding the request to the plug list
1055 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1056 * the plug list when the task sleeps by itself. For details, please see
1057 * schedule() where blk_schedule_flush_plug() is called.
1060 unsigned long magic; /* detect uninitialized use-cases */
1061 struct list_head list; /* requests */
1062 struct list_head mq_list; /* blk-mq requests */
1063 struct list_head cb_list; /* md requires an unplug callback */
1065 #define BLK_MAX_REQUEST_COUNT 16
1068 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1069 struct blk_plug_cb {
1070 struct list_head list;
1071 blk_plug_cb_fn callback;
1074 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1075 void *data, int size);
1076 extern void blk_start_plug(struct blk_plug *);
1077 extern void blk_finish_plug(struct blk_plug *);
1078 extern void blk_flush_plug_list(struct blk_plug *, bool);
1080 static inline void blk_flush_plug(struct task_struct *tsk)
1082 struct blk_plug *plug = tsk->plug;
1085 blk_flush_plug_list(plug, false);
1088 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1090 struct blk_plug *plug = tsk->plug;
1093 blk_flush_plug_list(plug, true);
1096 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1098 struct blk_plug *plug = tsk->plug;
1101 (!list_empty(&plug->list) ||
1102 !list_empty(&plug->mq_list) ||
1103 !list_empty(&plug->cb_list));
1109 #define blk_rq_tagged(rq) \
1110 ((rq)->mq_ctx || ((rq)->cmd_flags & REQ_QUEUED))
1111 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1112 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1113 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1114 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
1115 extern void blk_queue_free_tags(struct request_queue *);
1116 extern int blk_queue_resize_tags(struct request_queue *, int);
1117 extern void blk_queue_invalidate_tags(struct request_queue *);
1118 extern struct blk_queue_tag *blk_init_tags(int);
1119 extern void blk_free_tags(struct blk_queue_tag *);
1121 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1124 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1126 return bqt->tag_index[tag];
1129 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1131 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1132 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1133 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1134 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1135 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1136 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1137 sector_t nr_sects, gfp_t gfp_mask);
1138 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1139 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1141 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1142 nr_blocks << (sb->s_blocksize_bits - 9),
1145 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1146 sector_t nr_blocks, gfp_t gfp_mask)
1148 return blkdev_issue_zeroout(sb->s_bdev,
1149 block << (sb->s_blocksize_bits - 9),
1150 nr_blocks << (sb->s_blocksize_bits - 9),
1154 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1156 enum blk_default_limits {
1157 BLK_MAX_SEGMENTS = 128,
1158 BLK_SAFE_MAX_SECTORS = 255,
1159 BLK_DEF_MAX_SECTORS = 1024,
1160 BLK_MAX_SEGMENT_SIZE = 65536,
1161 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1164 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1166 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1168 return q->limits.bounce_pfn;
1171 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1173 return q->limits.seg_boundary_mask;
1176 static inline unsigned int queue_max_sectors(struct request_queue *q)
1178 return q->limits.max_sectors;
1181 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1183 return q->limits.max_hw_sectors;
1186 static inline unsigned short queue_max_segments(struct request_queue *q)
1188 return q->limits.max_segments;
1191 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1193 return q->limits.max_segment_size;
1196 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1200 if (q && q->limits.logical_block_size)
1201 retval = q->limits.logical_block_size;
1206 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1208 return queue_logical_block_size(bdev_get_queue(bdev));
1211 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1213 return q->limits.physical_block_size;
1216 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1218 return queue_physical_block_size(bdev_get_queue(bdev));
1221 static inline unsigned int queue_io_min(struct request_queue *q)
1223 return q->limits.io_min;
1226 static inline int bdev_io_min(struct block_device *bdev)
1228 return queue_io_min(bdev_get_queue(bdev));
1231 static inline unsigned int queue_io_opt(struct request_queue *q)
1233 return q->limits.io_opt;
1236 static inline int bdev_io_opt(struct block_device *bdev)
1238 return queue_io_opt(bdev_get_queue(bdev));
1241 static inline int queue_alignment_offset(struct request_queue *q)
1243 if (q->limits.misaligned)
1246 return q->limits.alignment_offset;
1249 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1251 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1252 unsigned int alignment = (sector << 9) & (granularity - 1);
1254 return (granularity + lim->alignment_offset - alignment)
1255 & (granularity - 1);
1258 static inline int bdev_alignment_offset(struct block_device *bdev)
1260 struct request_queue *q = bdev_get_queue(bdev);
1262 if (q->limits.misaligned)
1265 if (bdev != bdev->bd_contains)
1266 return bdev->bd_part->alignment_offset;
1268 return q->limits.alignment_offset;
1271 static inline int queue_discard_alignment(struct request_queue *q)
1273 if (q->limits.discard_misaligned)
1276 return q->limits.discard_alignment;
1279 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1281 unsigned int alignment, granularity, offset;
1283 if (!lim->max_discard_sectors)
1286 /* Why are these in bytes, not sectors? */
1287 alignment = lim->discard_alignment >> 9;
1288 granularity = lim->discard_granularity >> 9;
1292 /* Offset of the partition start in 'granularity' sectors */
1293 offset = sector_div(sector, granularity);
1295 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1296 offset = (granularity + alignment - offset) % granularity;
1298 /* Turn it back into bytes, gaah */
1302 static inline int bdev_discard_alignment(struct block_device *bdev)
1304 struct request_queue *q = bdev_get_queue(bdev);
1306 if (bdev != bdev->bd_contains)
1307 return bdev->bd_part->discard_alignment;
1309 return q->limits.discard_alignment;
1312 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1314 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1320 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1322 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1325 static inline unsigned int bdev_write_same(struct block_device *bdev)
1327 struct request_queue *q = bdev_get_queue(bdev);
1330 return q->limits.max_write_same_sectors;
1335 static inline int queue_dma_alignment(struct request_queue *q)
1337 return q ? q->dma_alignment : 511;
1340 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1343 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1344 return !(addr & alignment) && !(len & alignment);
1347 /* assumes size > 256 */
1348 static inline unsigned int blksize_bits(unsigned int size)
1350 unsigned int bits = 8;
1354 } while (size > 256);
1358 static inline unsigned int block_size(struct block_device *bdev)
1360 return bdev->bd_block_size;
1363 static inline bool queue_flush_queueable(struct request_queue *q)
1365 return !q->flush_not_queueable;
1368 typedef struct {struct page *v;} Sector;
1370 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1372 static inline void put_dev_sector(Sector p)
1374 page_cache_release(p.v);
1378 int kblockd_schedule_work(struct work_struct *work);
1379 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1380 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1382 #ifdef CONFIG_BLK_CGROUP
1384 * This should not be using sched_clock(). A real patch is in progress
1385 * to fix this up, until that is in place we need to disable preemption
1386 * around sched_clock() in this function and set_io_start_time_ns().
1388 static inline void set_start_time_ns(struct request *req)
1391 req->start_time_ns = sched_clock();
1395 static inline void set_io_start_time_ns(struct request *req)
1398 req->io_start_time_ns = sched_clock();
1402 static inline uint64_t rq_start_time_ns(struct request *req)
1404 return req->start_time_ns;
1407 static inline uint64_t rq_io_start_time_ns(struct request *req)
1409 return req->io_start_time_ns;
1412 static inline void set_start_time_ns(struct request *req) {}
1413 static inline void set_io_start_time_ns(struct request *req) {}
1414 static inline uint64_t rq_start_time_ns(struct request *req)
1418 static inline uint64_t rq_io_start_time_ns(struct request *req)
1424 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1425 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1426 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1427 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1429 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1431 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */
1432 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */
1434 struct blk_integrity_exchg {
1438 unsigned int data_size;
1439 unsigned short sector_size;
1440 const char *disk_name;
1443 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
1444 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
1445 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
1446 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);
1448 struct blk_integrity {
1449 integrity_gen_fn *generate_fn;
1450 integrity_vrfy_fn *verify_fn;
1451 integrity_set_tag_fn *set_tag_fn;
1452 integrity_get_tag_fn *get_tag_fn;
1454 unsigned short flags;
1455 unsigned short tuple_size;
1456 unsigned short sector_size;
1457 unsigned short tag_size;
1461 struct kobject kobj;
1464 extern bool blk_integrity_is_initialized(struct gendisk *);
1465 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1466 extern void blk_integrity_unregister(struct gendisk *);
1467 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1468 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1469 struct scatterlist *);
1470 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1471 extern int blk_integrity_merge_rq(struct request_queue *, struct request *,
1473 extern int blk_integrity_merge_bio(struct request_queue *, struct request *,
1477 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1479 return bdev->bd_disk->integrity;
1482 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1484 return disk->integrity;
1487 static inline int blk_integrity_rq(struct request *rq)
1489 if (rq->bio == NULL)
1492 return bio_integrity(rq->bio);
1495 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1498 q->limits.max_integrity_segments = segs;
1501 static inline unsigned short
1502 queue_max_integrity_segments(struct request_queue *q)
1504 return q->limits.max_integrity_segments;
1507 #else /* CONFIG_BLK_DEV_INTEGRITY */
1510 struct block_device;
1512 struct blk_integrity;
1514 static inline int blk_integrity_rq(struct request *rq)
1518 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1523 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1525 struct scatterlist *s)
1529 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1533 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1537 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1541 static inline int blk_integrity_register(struct gendisk *d,
1542 struct blk_integrity *b)
1546 static inline void blk_integrity_unregister(struct gendisk *d)
1549 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1553 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1557 static inline int blk_integrity_merge_rq(struct request_queue *rq,
1563 static inline int blk_integrity_merge_bio(struct request_queue *rq,
1569 static inline bool blk_integrity_is_initialized(struct gendisk *g)
1574 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1576 struct block_device_operations {
1577 int (*open) (struct block_device *, fmode_t);
1578 void (*release) (struct gendisk *, fmode_t);
1579 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1580 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1581 int (*direct_access) (struct block_device *, sector_t,
1582 void **, unsigned long *);
1583 unsigned int (*check_events) (struct gendisk *disk,
1584 unsigned int clearing);
1585 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1586 int (*media_changed) (struct gendisk *);
1587 void (*unlock_native_capacity) (struct gendisk *);
1588 int (*revalidate_disk) (struct gendisk *);
1589 int (*getgeo)(struct block_device *, struct hd_geometry *);
1590 /* this callback is with swap_lock and sometimes page table lock held */
1591 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1592 struct module *owner;
1595 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1597 #else /* CONFIG_BLOCK */
1599 * stubs for when the block layer is configured out
1601 #define buffer_heads_over_limit 0
1603 static inline long nr_blockdev_pages(void)
1611 static inline void blk_start_plug(struct blk_plug *plug)
1615 static inline void blk_finish_plug(struct blk_plug *plug)
1619 static inline void blk_flush_plug(struct task_struct *task)
1623 static inline void blk_schedule_flush_plug(struct task_struct *task)
1628 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1633 #endif /* CONFIG_BLOCK */