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;
40 #define BLKDEV_MIN_RQ 4
41 #define BLKDEV_MAX_RQ 128 /* Default maximum */
44 * Maximum number of blkcg policies allowed to be registered concurrently.
45 * Defined here to simplify include dependency.
47 #define BLKCG_MAX_POLS 2
50 typedef void (rq_end_io_fn)(struct request *, int);
52 #define BLK_RL_SYNCFULL (1U << 0)
53 #define BLK_RL_ASYNCFULL (1U << 1)
56 struct request_queue *q; /* the queue this rl belongs to */
57 #ifdef CONFIG_BLK_CGROUP
58 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
61 * count[], starved[], and wait[] are indexed by
62 * BLK_RW_SYNC/BLK_RW_ASYNC
67 wait_queue_head_t wait[2];
72 * request command types
74 enum rq_cmd_type_bits {
75 REQ_TYPE_FS = 1, /* fs request */
76 REQ_TYPE_BLOCK_PC, /* scsi command */
77 REQ_TYPE_SENSE, /* sense request */
78 REQ_TYPE_PM_SUSPEND, /* suspend request */
79 REQ_TYPE_PM_RESUME, /* resume request */
80 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */
81 REQ_TYPE_SPECIAL, /* driver defined type */
83 * for ATA/ATAPI devices. this really doesn't belong here, ide should
84 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
85 * private REQ_LB opcodes to differentiate what type of request this is
87 REQ_TYPE_ATA_TASKFILE,
91 #define BLK_MAX_CDB 16
94 * Try to put the fields that are referenced together in the same cacheline.
96 * If you modify this structure, make sure to update blk_rq_init() and
97 * especially blk_mq_rq_ctx_init() to take care of the added fields.
100 struct list_head queuelist;
102 struct call_single_data csd;
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 chunk_sectors;
285 unsigned int max_sectors;
286 unsigned int max_segment_size;
287 unsigned int physical_block_size;
288 unsigned int alignment_offset;
291 unsigned int max_discard_sectors;
292 unsigned int max_write_same_sectors;
293 unsigned int discard_granularity;
294 unsigned int discard_alignment;
296 unsigned short logical_block_size;
297 unsigned short max_segments;
298 unsigned short max_integrity_segments;
300 unsigned char misaligned;
301 unsigned char discard_misaligned;
302 unsigned char cluster;
303 unsigned char discard_zeroes_data;
304 unsigned char raid_partial_stripes_expensive;
307 struct request_queue {
309 * Together with queue_head for cacheline sharing
311 struct list_head queue_head;
312 struct request *last_merge;
313 struct elevator_queue *elevator;
314 int nr_rqs[2]; /* # allocated [a]sync rqs */
315 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
318 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
319 * is used, root blkg allocates from @q->root_rl and all other
320 * blkgs from their own blkg->rl. Which one to use should be
321 * determined using bio_request_list().
323 struct request_list root_rl;
325 request_fn_proc *request_fn;
326 make_request_fn *make_request_fn;
327 prep_rq_fn *prep_rq_fn;
328 unprep_rq_fn *unprep_rq_fn;
329 merge_bvec_fn *merge_bvec_fn;
330 softirq_done_fn *softirq_done_fn;
331 rq_timed_out_fn *rq_timed_out_fn;
332 dma_drain_needed_fn *dma_drain_needed;
333 lld_busy_fn *lld_busy_fn;
335 struct blk_mq_ops *mq_ops;
337 unsigned int *mq_map;
340 struct blk_mq_ctx __percpu *queue_ctx;
341 unsigned int nr_queues;
343 /* hw dispatch queues */
344 struct blk_mq_hw_ctx **queue_hw_ctx;
345 unsigned int nr_hw_queues;
348 * Dispatch queue sorting
351 struct request *boundary_rq;
354 * Delayed queue handling
356 struct delayed_work delay_work;
358 struct backing_dev_info backing_dev_info;
361 * The queue owner gets to use this for whatever they like.
362 * ll_rw_blk doesn't touch it.
367 * various queue flags, see QUEUE_* below
369 unsigned long queue_flags;
372 * ida allocated id for this queue. Used to index queues from
378 * queue needs bounce pages for pages above this limit
383 * protects queue structures from reentrancy. ->__queue_lock should
384 * _never_ be used directly, it is queue private. always use
387 spinlock_t __queue_lock;
388 spinlock_t *queue_lock;
398 struct kobject mq_kobj;
400 #ifdef CONFIG_PM_RUNTIME
403 unsigned int nr_pending;
409 unsigned long nr_requests; /* Max # of requests */
410 unsigned int nr_congestion_on;
411 unsigned int nr_congestion_off;
412 unsigned int nr_batching;
414 unsigned int dma_drain_size;
415 void *dma_drain_buffer;
416 unsigned int dma_pad_mask;
417 unsigned int dma_alignment;
419 struct blk_queue_tag *queue_tags;
420 struct list_head tag_busy_list;
422 unsigned int nr_sorted;
423 unsigned int in_flight[2];
425 * Number of active block driver functions for which blk_drain_queue()
426 * must wait. Must be incremented around functions that unlock the
427 * queue_lock internally, e.g. scsi_request_fn().
429 unsigned int request_fn_active;
431 unsigned int rq_timeout;
432 struct timer_list timeout;
433 struct list_head timeout_list;
435 struct list_head icq_list;
436 #ifdef CONFIG_BLK_CGROUP
437 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
438 struct blkcg_gq *root_blkg;
439 struct list_head blkg_list;
442 struct queue_limits limits;
447 unsigned int sg_timeout;
448 unsigned int sg_reserved_size;
450 #ifdef CONFIG_BLK_DEV_IO_TRACE
451 struct blk_trace *blk_trace;
454 * for flush operations
456 unsigned int flush_flags;
457 unsigned int flush_not_queueable:1;
458 unsigned int flush_queue_delayed:1;
459 unsigned int flush_pending_idx:1;
460 unsigned int flush_running_idx:1;
461 unsigned long flush_pending_since;
462 struct list_head flush_queue[2];
463 struct list_head flush_data_in_flight;
464 struct request *flush_rq;
465 spinlock_t mq_flush_lock;
467 struct list_head requeue_list;
468 spinlock_t requeue_lock;
469 struct work_struct requeue_work;
471 struct mutex sysfs_lock;
476 #if defined(CONFIG_BLK_DEV_BSG)
477 bsg_job_fn *bsg_job_fn;
479 struct bsg_class_device bsg_dev;
482 #ifdef CONFIG_BLK_DEV_THROTTLING
484 struct throtl_data *td;
486 struct rcu_head rcu_head;
487 wait_queue_head_t mq_freeze_wq;
488 struct percpu_ref mq_usage_counter;
489 struct list_head all_q_node;
491 struct blk_mq_tag_set *tag_set;
492 struct list_head tag_set_list;
495 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
496 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
497 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
498 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
499 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
500 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
501 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
502 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
503 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
504 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
505 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
506 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
507 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
508 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
509 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
510 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
511 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
512 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
513 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
514 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
515 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
516 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
517 #define QUEUE_FLAG_SG_GAPS 22 /* queue doesn't support SG gaps */
519 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
520 (1 << QUEUE_FLAG_STACKABLE) | \
521 (1 << QUEUE_FLAG_SAME_COMP) | \
522 (1 << QUEUE_FLAG_ADD_RANDOM))
524 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
525 (1 << QUEUE_FLAG_SAME_COMP))
527 static inline void queue_lockdep_assert_held(struct request_queue *q)
530 lockdep_assert_held(q->queue_lock);
533 static inline void queue_flag_set_unlocked(unsigned int flag,
534 struct request_queue *q)
536 __set_bit(flag, &q->queue_flags);
539 static inline int queue_flag_test_and_clear(unsigned int flag,
540 struct request_queue *q)
542 queue_lockdep_assert_held(q);
544 if (test_bit(flag, &q->queue_flags)) {
545 __clear_bit(flag, &q->queue_flags);
552 static inline int queue_flag_test_and_set(unsigned int flag,
553 struct request_queue *q)
555 queue_lockdep_assert_held(q);
557 if (!test_bit(flag, &q->queue_flags)) {
558 __set_bit(flag, &q->queue_flags);
565 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
567 queue_lockdep_assert_held(q);
568 __set_bit(flag, &q->queue_flags);
571 static inline void queue_flag_clear_unlocked(unsigned int flag,
572 struct request_queue *q)
574 __clear_bit(flag, &q->queue_flags);
577 static inline int queue_in_flight(struct request_queue *q)
579 return q->in_flight[0] + q->in_flight[1];
582 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
584 queue_lockdep_assert_held(q);
585 __clear_bit(flag, &q->queue_flags);
588 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
589 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
590 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
591 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
592 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
593 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
594 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
595 #define blk_queue_noxmerges(q) \
596 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
597 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
598 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
599 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
600 #define blk_queue_stackable(q) \
601 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
602 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
603 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
604 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
606 #define blk_noretry_request(rq) \
607 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
608 REQ_FAILFAST_DRIVER))
610 #define blk_account_rq(rq) \
611 (((rq)->cmd_flags & REQ_STARTED) && \
612 ((rq)->cmd_type == REQ_TYPE_FS))
614 #define blk_pm_request(rq) \
615 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
616 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
618 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
619 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
620 /* rq->queuelist of dequeued request must be list_empty() */
621 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
623 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
625 #define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
628 * Driver can handle struct request, if it either has an old style
629 * request_fn defined, or is blk-mq based.
631 static inline bool queue_is_rq_based(struct request_queue *q)
633 return q->request_fn || q->mq_ops;
636 static inline unsigned int blk_queue_cluster(struct request_queue *q)
638 return q->limits.cluster;
642 * We regard a request as sync, if either a read or a sync write
644 static inline bool rw_is_sync(unsigned int rw_flags)
646 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
649 static inline bool rq_is_sync(struct request *rq)
651 return rw_is_sync(rq->cmd_flags);
654 static inline bool blk_rl_full(struct request_list *rl, bool sync)
656 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
658 return rl->flags & flag;
661 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
663 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
668 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
670 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
675 static inline bool rq_mergeable(struct request *rq)
677 if (rq->cmd_type != REQ_TYPE_FS)
680 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
686 static inline bool blk_check_merge_flags(unsigned int flags1,
689 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
692 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
695 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
701 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
703 if (bio_data(a) == bio_data(b))
710 * q->prep_rq_fn return values
712 #define BLKPREP_OK 0 /* serve it */
713 #define BLKPREP_KILL 1 /* fatal error, kill */
714 #define BLKPREP_DEFER 2 /* leave on queue */
716 extern unsigned long blk_max_low_pfn, blk_max_pfn;
719 * standard bounce addresses:
721 * BLK_BOUNCE_HIGH : bounce all highmem pages
722 * BLK_BOUNCE_ANY : don't bounce anything
723 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
726 #if BITS_PER_LONG == 32
727 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
729 #define BLK_BOUNCE_HIGH -1ULL
731 #define BLK_BOUNCE_ANY (-1ULL)
732 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
735 * default timeout for SG_IO if none specified
737 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
738 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
741 extern int init_emergency_isa_pool(void);
742 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
744 static inline int init_emergency_isa_pool(void)
748 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
751 #endif /* CONFIG_MMU */
757 unsigned long offset;
762 struct req_iterator {
763 struct bvec_iter iter;
767 /* This should not be used directly - use rq_for_each_segment */
768 #define for_each_bio(_bio) \
769 for (; _bio; _bio = _bio->bi_next)
770 #define __rq_for_each_bio(_bio, rq) \
772 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
774 #define rq_for_each_segment(bvl, _rq, _iter) \
775 __rq_for_each_bio(_iter.bio, _rq) \
776 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
778 #define rq_iter_last(bvec, _iter) \
779 (_iter.bio->bi_next == NULL && \
780 bio_iter_last(bvec, _iter.iter))
782 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
783 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
785 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
786 extern void rq_flush_dcache_pages(struct request *rq);
788 static inline void rq_flush_dcache_pages(struct request *rq)
793 extern int blk_register_queue(struct gendisk *disk);
794 extern void blk_unregister_queue(struct gendisk *disk);
795 extern void generic_make_request(struct bio *bio);
796 extern void blk_rq_init(struct request_queue *q, struct request *rq);
797 extern void blk_put_request(struct request *);
798 extern void __blk_put_request(struct request_queue *, struct request *);
799 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
800 extern struct request *blk_make_request(struct request_queue *, struct bio *,
802 extern void blk_rq_set_block_pc(struct request *);
803 extern void blk_requeue_request(struct request_queue *, struct request *);
804 extern void blk_add_request_payload(struct request *rq, struct page *page,
806 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
807 extern int blk_lld_busy(struct request_queue *q);
808 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
809 struct bio_set *bs, gfp_t gfp_mask,
810 int (*bio_ctr)(struct bio *, struct bio *, void *),
812 extern void blk_rq_unprep_clone(struct request *rq);
813 extern int blk_insert_cloned_request(struct request_queue *q,
815 extern void blk_delay_queue(struct request_queue *, unsigned long);
816 extern void blk_recount_segments(struct request_queue *, struct bio *);
817 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
818 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
819 unsigned int, void __user *);
820 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
821 unsigned int, void __user *);
822 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
823 struct scsi_ioctl_command __user *);
825 extern void blk_queue_bio(struct request_queue *q, struct bio *bio);
828 * A queue has just exitted congestion. Note this in the global counter of
829 * congested queues, and wake up anyone who was waiting for requests to be
832 static inline void blk_clear_queue_congested(struct request_queue *q, int sync)
834 clear_bdi_congested(&q->backing_dev_info, sync);
838 * A queue has just entered congestion. Flag that in the queue's VM-visible
839 * state flags and increment the global gounter of congested queues.
841 static inline void blk_set_queue_congested(struct request_queue *q, int sync)
843 set_bdi_congested(&q->backing_dev_info, sync);
846 extern void blk_start_queue(struct request_queue *q);
847 extern void blk_stop_queue(struct request_queue *q);
848 extern void blk_sync_queue(struct request_queue *q);
849 extern void __blk_stop_queue(struct request_queue *q);
850 extern void __blk_run_queue(struct request_queue *q);
851 extern void blk_run_queue(struct request_queue *);
852 extern void blk_run_queue_async(struct request_queue *q);
853 extern int blk_rq_map_user(struct request_queue *, struct request *,
854 struct rq_map_data *, void __user *, unsigned long,
856 extern int blk_rq_unmap_user(struct bio *);
857 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
858 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
859 struct rq_map_data *, const struct sg_iovec *,
860 int, unsigned int, gfp_t);
861 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
862 struct request *, int);
863 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
864 struct request *, int, rq_end_io_fn *);
866 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
868 return bdev->bd_disk->queue;
872 * blk_rq_pos() : the current sector
873 * blk_rq_bytes() : bytes left in the entire request
874 * blk_rq_cur_bytes() : bytes left in the current segment
875 * blk_rq_err_bytes() : bytes left till the next error boundary
876 * blk_rq_sectors() : sectors left in the entire request
877 * blk_rq_cur_sectors() : sectors left in the current segment
879 static inline sector_t blk_rq_pos(const struct request *rq)
884 static inline unsigned int blk_rq_bytes(const struct request *rq)
886 return rq->__data_len;
889 static inline int blk_rq_cur_bytes(const struct request *rq)
891 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
894 extern unsigned int blk_rq_err_bytes(const struct request *rq);
896 static inline unsigned int blk_rq_sectors(const struct request *rq)
898 return blk_rq_bytes(rq) >> 9;
901 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
903 return blk_rq_cur_bytes(rq) >> 9;
906 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
907 unsigned int cmd_flags)
909 if (unlikely(cmd_flags & REQ_DISCARD))
910 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
912 if (unlikely(cmd_flags & REQ_WRITE_SAME))
913 return q->limits.max_write_same_sectors;
915 return q->limits.max_sectors;
919 * Return maximum size of a request at given offset. Only valid for
920 * file system requests.
922 static inline unsigned int blk_max_size_offset(struct request_queue *q,
925 if (!q->limits.chunk_sectors)
926 return q->limits.max_sectors;
928 return q->limits.chunk_sectors -
929 (offset & (q->limits.chunk_sectors - 1));
932 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
934 struct request_queue *q = rq->q;
936 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
937 return q->limits.max_hw_sectors;
939 if (!q->limits.chunk_sectors)
940 return blk_queue_get_max_sectors(q, rq->cmd_flags);
942 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
943 blk_queue_get_max_sectors(q, rq->cmd_flags));
946 static inline unsigned int blk_rq_count_bios(struct request *rq)
948 unsigned int nr_bios = 0;
951 __rq_for_each_bio(bio, rq)
958 * Request issue related functions.
960 extern struct request *blk_peek_request(struct request_queue *q);
961 extern void blk_start_request(struct request *rq);
962 extern struct request *blk_fetch_request(struct request_queue *q);
965 * Request completion related functions.
967 * blk_update_request() completes given number of bytes and updates
968 * the request without completing it.
970 * blk_end_request() and friends. __blk_end_request() must be called
971 * with the request queue spinlock acquired.
973 * Several drivers define their own end_request and call
974 * blk_end_request() for parts of the original function.
975 * This prevents code duplication in drivers.
977 extern bool blk_update_request(struct request *rq, int error,
978 unsigned int nr_bytes);
979 extern void blk_finish_request(struct request *rq, int error);
980 extern bool blk_end_request(struct request *rq, int error,
981 unsigned int nr_bytes);
982 extern void blk_end_request_all(struct request *rq, int error);
983 extern bool blk_end_request_cur(struct request *rq, int error);
984 extern bool blk_end_request_err(struct request *rq, int error);
985 extern bool __blk_end_request(struct request *rq, int error,
986 unsigned int nr_bytes);
987 extern void __blk_end_request_all(struct request *rq, int error);
988 extern bool __blk_end_request_cur(struct request *rq, int error);
989 extern bool __blk_end_request_err(struct request *rq, int error);
991 extern void blk_complete_request(struct request *);
992 extern void __blk_complete_request(struct request *);
993 extern void blk_abort_request(struct request *);
994 extern void blk_unprep_request(struct request *);
997 * Access functions for manipulating queue properties
999 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
1000 spinlock_t *lock, int node_id);
1001 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
1002 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
1003 request_fn_proc *, spinlock_t *);
1004 extern void blk_cleanup_queue(struct request_queue *);
1005 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1006 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1007 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
1008 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1009 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1010 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1011 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1012 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1013 unsigned int max_discard_sectors);
1014 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1015 unsigned int max_write_same_sectors);
1016 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
1017 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1018 extern void blk_queue_alignment_offset(struct request_queue *q,
1019 unsigned int alignment);
1020 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1021 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1022 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1023 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1024 extern void blk_set_default_limits(struct queue_limits *lim);
1025 extern void blk_set_stacking_limits(struct queue_limits *lim);
1026 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1028 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1030 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1032 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1033 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1034 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1035 extern int blk_queue_dma_drain(struct request_queue *q,
1036 dma_drain_needed_fn *dma_drain_needed,
1037 void *buf, unsigned int size);
1038 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1039 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1040 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1041 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1042 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
1043 extern void blk_queue_dma_alignment(struct request_queue *, int);
1044 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1045 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1046 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1047 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1048 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
1049 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1050 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1052 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1053 extern int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
1054 struct scatterlist *sglist);
1055 extern void blk_dump_rq_flags(struct request *, char *);
1056 extern long nr_blockdev_pages(void);
1058 bool __must_check blk_get_queue(struct request_queue *);
1059 struct request_queue *blk_alloc_queue(gfp_t);
1060 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1061 extern void blk_put_queue(struct request_queue *);
1064 * block layer runtime pm functions
1066 #ifdef CONFIG_PM_RUNTIME
1067 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1068 extern int blk_pre_runtime_suspend(struct request_queue *q);
1069 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1070 extern void blk_pre_runtime_resume(struct request_queue *q);
1071 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1073 static inline void blk_pm_runtime_init(struct request_queue *q,
1074 struct device *dev) {}
1075 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1079 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1080 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1081 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1085 * blk_plug permits building a queue of related requests by holding the I/O
1086 * fragments for a short period. This allows merging of sequential requests
1087 * into single larger request. As the requests are moved from a per-task list to
1088 * the device's request_queue in a batch, this results in improved scalability
1089 * as the lock contention for request_queue lock is reduced.
1091 * It is ok not to disable preemption when adding the request to the plug list
1092 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1093 * the plug list when the task sleeps by itself. For details, please see
1094 * schedule() where blk_schedule_flush_plug() is called.
1097 struct list_head list; /* requests */
1098 struct list_head mq_list; /* blk-mq requests */
1099 struct list_head cb_list; /* md requires an unplug callback */
1101 #define BLK_MAX_REQUEST_COUNT 16
1104 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1105 struct blk_plug_cb {
1106 struct list_head list;
1107 blk_plug_cb_fn callback;
1110 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1111 void *data, int size);
1112 extern void blk_start_plug(struct blk_plug *);
1113 extern void blk_finish_plug(struct blk_plug *);
1114 extern void blk_flush_plug_list(struct blk_plug *, bool);
1116 static inline void blk_flush_plug(struct task_struct *tsk)
1118 struct blk_plug *plug = tsk->plug;
1121 blk_flush_plug_list(plug, false);
1124 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1126 struct blk_plug *plug = tsk->plug;
1129 blk_flush_plug_list(plug, true);
1132 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1134 struct blk_plug *plug = tsk->plug;
1137 (!list_empty(&plug->list) ||
1138 !list_empty(&plug->mq_list) ||
1139 !list_empty(&plug->cb_list));
1145 #define blk_rq_tagged(rq) \
1146 ((rq)->mq_ctx || ((rq)->cmd_flags & REQ_QUEUED))
1147 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1148 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1149 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1150 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
1151 extern void blk_queue_free_tags(struct request_queue *);
1152 extern int blk_queue_resize_tags(struct request_queue *, int);
1153 extern void blk_queue_invalidate_tags(struct request_queue *);
1154 extern struct blk_queue_tag *blk_init_tags(int);
1155 extern void blk_free_tags(struct blk_queue_tag *);
1157 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1160 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1162 return bqt->tag_index[tag];
1165 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1167 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1168 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1169 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1170 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1171 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1172 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1173 sector_t nr_sects, gfp_t gfp_mask);
1174 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1175 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1177 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1178 nr_blocks << (sb->s_blocksize_bits - 9),
1181 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1182 sector_t nr_blocks, gfp_t gfp_mask)
1184 return blkdev_issue_zeroout(sb->s_bdev,
1185 block << (sb->s_blocksize_bits - 9),
1186 nr_blocks << (sb->s_blocksize_bits - 9),
1190 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1192 enum blk_default_limits {
1193 BLK_MAX_SEGMENTS = 128,
1194 BLK_SAFE_MAX_SECTORS = 255,
1195 BLK_DEF_MAX_SECTORS = 1024,
1196 BLK_MAX_SEGMENT_SIZE = 65536,
1197 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1200 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1202 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1204 return q->limits.bounce_pfn;
1207 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1209 return q->limits.seg_boundary_mask;
1212 static inline unsigned int queue_max_sectors(struct request_queue *q)
1214 return q->limits.max_sectors;
1217 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1219 return q->limits.max_hw_sectors;
1222 static inline unsigned short queue_max_segments(struct request_queue *q)
1224 return q->limits.max_segments;
1227 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1229 return q->limits.max_segment_size;
1232 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1236 if (q && q->limits.logical_block_size)
1237 retval = q->limits.logical_block_size;
1242 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1244 return queue_logical_block_size(bdev_get_queue(bdev));
1247 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1249 return q->limits.physical_block_size;
1252 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1254 return queue_physical_block_size(bdev_get_queue(bdev));
1257 static inline unsigned int queue_io_min(struct request_queue *q)
1259 return q->limits.io_min;
1262 static inline int bdev_io_min(struct block_device *bdev)
1264 return queue_io_min(bdev_get_queue(bdev));
1267 static inline unsigned int queue_io_opt(struct request_queue *q)
1269 return q->limits.io_opt;
1272 static inline int bdev_io_opt(struct block_device *bdev)
1274 return queue_io_opt(bdev_get_queue(bdev));
1277 static inline int queue_alignment_offset(struct request_queue *q)
1279 if (q->limits.misaligned)
1282 return q->limits.alignment_offset;
1285 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1287 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1288 unsigned int alignment = (sector << 9) & (granularity - 1);
1290 return (granularity + lim->alignment_offset - alignment)
1291 & (granularity - 1);
1294 static inline int bdev_alignment_offset(struct block_device *bdev)
1296 struct request_queue *q = bdev_get_queue(bdev);
1298 if (q->limits.misaligned)
1301 if (bdev != bdev->bd_contains)
1302 return bdev->bd_part->alignment_offset;
1304 return q->limits.alignment_offset;
1307 static inline int queue_discard_alignment(struct request_queue *q)
1309 if (q->limits.discard_misaligned)
1312 return q->limits.discard_alignment;
1315 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1317 unsigned int alignment, granularity, offset;
1319 if (!lim->max_discard_sectors)
1322 /* Why are these in bytes, not sectors? */
1323 alignment = lim->discard_alignment >> 9;
1324 granularity = lim->discard_granularity >> 9;
1328 /* Offset of the partition start in 'granularity' sectors */
1329 offset = sector_div(sector, granularity);
1331 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1332 offset = (granularity + alignment - offset) % granularity;
1334 /* Turn it back into bytes, gaah */
1338 static inline int bdev_discard_alignment(struct block_device *bdev)
1340 struct request_queue *q = bdev_get_queue(bdev);
1342 if (bdev != bdev->bd_contains)
1343 return bdev->bd_part->discard_alignment;
1345 return q->limits.discard_alignment;
1348 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1350 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1356 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1358 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1361 static inline unsigned int bdev_write_same(struct block_device *bdev)
1363 struct request_queue *q = bdev_get_queue(bdev);
1366 return q->limits.max_write_same_sectors;
1371 static inline int queue_dma_alignment(struct request_queue *q)
1373 return q ? q->dma_alignment : 511;
1376 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1379 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1380 return !(addr & alignment) && !(len & alignment);
1383 /* assumes size > 256 */
1384 static inline unsigned int blksize_bits(unsigned int size)
1386 unsigned int bits = 8;
1390 } while (size > 256);
1394 static inline unsigned int block_size(struct block_device *bdev)
1396 return bdev->bd_block_size;
1399 static inline bool queue_flush_queueable(struct request_queue *q)
1401 return !q->flush_not_queueable;
1404 typedef struct {struct page *v;} Sector;
1406 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1408 static inline void put_dev_sector(Sector p)
1410 page_cache_release(p.v);
1414 int kblockd_schedule_work(struct work_struct *work);
1415 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1416 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1418 #ifdef CONFIG_BLK_CGROUP
1420 * This should not be using sched_clock(). A real patch is in progress
1421 * to fix this up, until that is in place we need to disable preemption
1422 * around sched_clock() in this function and set_io_start_time_ns().
1424 static inline void set_start_time_ns(struct request *req)
1427 req->start_time_ns = sched_clock();
1431 static inline void set_io_start_time_ns(struct request *req)
1434 req->io_start_time_ns = sched_clock();
1438 static inline uint64_t rq_start_time_ns(struct request *req)
1440 return req->start_time_ns;
1443 static inline uint64_t rq_io_start_time_ns(struct request *req)
1445 return req->io_start_time_ns;
1448 static inline void set_start_time_ns(struct request *req) {}
1449 static inline void set_io_start_time_ns(struct request *req) {}
1450 static inline uint64_t rq_start_time_ns(struct request *req)
1454 static inline uint64_t rq_io_start_time_ns(struct request *req)
1460 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1461 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1462 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1463 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1465 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1467 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */
1468 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */
1470 struct blk_integrity_exchg {
1474 unsigned int data_size;
1475 unsigned short sector_size;
1476 const char *disk_name;
1479 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
1480 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
1481 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
1482 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);
1484 struct blk_integrity {
1485 integrity_gen_fn *generate_fn;
1486 integrity_vrfy_fn *verify_fn;
1487 integrity_set_tag_fn *set_tag_fn;
1488 integrity_get_tag_fn *get_tag_fn;
1490 unsigned short flags;
1491 unsigned short tuple_size;
1492 unsigned short sector_size;
1493 unsigned short tag_size;
1497 struct kobject kobj;
1500 extern bool blk_integrity_is_initialized(struct gendisk *);
1501 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1502 extern void blk_integrity_unregister(struct gendisk *);
1503 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1504 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1505 struct scatterlist *);
1506 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1507 extern int blk_integrity_merge_rq(struct request_queue *, struct request *,
1509 extern int blk_integrity_merge_bio(struct request_queue *, struct request *,
1513 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1515 return bdev->bd_disk->integrity;
1518 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1520 return disk->integrity;
1523 static inline int blk_integrity_rq(struct request *rq)
1525 if (rq->bio == NULL)
1528 return bio_integrity(rq->bio);
1531 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1534 q->limits.max_integrity_segments = segs;
1537 static inline unsigned short
1538 queue_max_integrity_segments(struct request_queue *q)
1540 return q->limits.max_integrity_segments;
1543 #else /* CONFIG_BLK_DEV_INTEGRITY */
1546 struct block_device;
1548 struct blk_integrity;
1550 static inline int blk_integrity_rq(struct request *rq)
1554 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1559 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1561 struct scatterlist *s)
1565 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1569 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1573 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1577 static inline int blk_integrity_register(struct gendisk *d,
1578 struct blk_integrity *b)
1582 static inline void blk_integrity_unregister(struct gendisk *d)
1585 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1589 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1593 static inline int blk_integrity_merge_rq(struct request_queue *rq,
1599 static inline int blk_integrity_merge_bio(struct request_queue *rq,
1605 static inline bool blk_integrity_is_initialized(struct gendisk *g)
1610 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1612 struct block_device_operations {
1613 int (*open) (struct block_device *, fmode_t);
1614 void (*release) (struct gendisk *, fmode_t);
1615 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1616 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1617 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1618 int (*direct_access) (struct block_device *, sector_t,
1619 void **, unsigned long *);
1620 unsigned int (*check_events) (struct gendisk *disk,
1621 unsigned int clearing);
1622 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1623 int (*media_changed) (struct gendisk *);
1624 void (*unlock_native_capacity) (struct gendisk *);
1625 int (*revalidate_disk) (struct gendisk *);
1626 int (*getgeo)(struct block_device *, struct hd_geometry *);
1627 /* this callback is with swap_lock and sometimes page table lock held */
1628 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1629 struct module *owner;
1632 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1634 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1635 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1636 struct writeback_control *);
1637 #else /* CONFIG_BLOCK */
1639 struct block_device;
1642 * stubs for when the block layer is configured out
1644 #define buffer_heads_over_limit 0
1646 static inline long nr_blockdev_pages(void)
1654 static inline void blk_start_plug(struct blk_plug *plug)
1658 static inline void blk_finish_plug(struct blk_plug *plug)
1662 static inline void blk_flush_plug(struct task_struct *task)
1666 static inline void blk_schedule_flush_plug(struct task_struct *task)
1671 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1676 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1677 sector_t *error_sector)
1682 #endif /* CONFIG_BLOCK */