1 #ifndef _LINUX_BLKDEV_H
2 #define _LINUX_BLKDEV_H
4 #include <linux/sched.h>
8 #include <linux/major.h>
9 #include <linux/genhd.h>
10 #include <linux/list.h>
11 #include <linux/llist.h>
12 #include <linux/timer.h>
13 #include <linux/workqueue.h>
14 #include <linux/pagemap.h>
15 #include <linux/backing-dev-defs.h>
16 #include <linux/wait.h>
17 #include <linux/mempool.h>
18 #include <linux/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>
25 #include <linux/scatterlist.h>
28 struct scsi_ioctl_command;
31 struct elevator_queue;
37 struct blk_flush_queue;
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_DRV_PRIV, /* driver defined types from here */
80 #define BLK_MAX_CDB 16
83 * Try to put the fields that are referenced together in the same cacheline.
85 * If you modify this structure, make sure to update blk_rq_init() and
86 * especially blk_mq_rq_ctx_init() to take care of the added fields.
89 struct list_head queuelist;
91 struct call_single_data csd;
92 struct work_struct work;
93 unsigned long fifo_time;
96 struct request_queue *q;
97 struct blk_mq_ctx *mq_ctx;
101 unsigned long atomic_flags;
105 /* the following two fields are internal, NEVER access directly */
106 unsigned int __data_len; /* total data len */
107 sector_t __sector; /* sector cursor */
113 * The hash is used inside the scheduler, and killed once the
114 * request reaches the dispatch list. The ipi_list is only used
115 * to queue the request for softirq completion, which is long
116 * after the request has been unhashed (and even removed from
117 * the dispatch list).
120 struct hlist_node hash; /* merge hash */
121 struct list_head ipi_list;
125 * The rb_node is only used inside the io scheduler, requests
126 * are pruned when moved to the dispatch queue. So let the
127 * completion_data share space with the rb_node.
130 struct rb_node rb_node; /* sort/lookup */
131 void *completion_data;
135 * Three pointers are available for the IO schedulers, if they need
136 * more they have to dynamically allocate it. Flush requests are
137 * never put on the IO scheduler. So let the flush fields share
138 * space with the elevator data.
148 struct list_head list;
149 rq_end_io_fn *saved_end_io;
153 struct gendisk *rq_disk;
154 struct hd_struct *part;
155 unsigned long start_time;
156 #ifdef CONFIG_BLK_CGROUP
157 struct request_list *rl; /* rl this rq is alloced from */
158 unsigned long long start_time_ns;
159 unsigned long long io_start_time_ns; /* when passed to hardware */
161 /* Number of scatter-gather DMA addr+len pairs after
162 * physical address coalescing is performed.
164 unsigned short nr_phys_segments;
165 #if defined(CONFIG_BLK_DEV_INTEGRITY)
166 unsigned short nr_integrity_segments;
169 unsigned short ioprio;
171 void *special; /* opaque pointer available for LLD use */
177 * when request is used as a packet command carrier
179 unsigned char __cmd[BLK_MAX_CDB];
181 unsigned short cmd_len;
183 unsigned int extra_len; /* length of alignment and padding */
184 unsigned int sense_len;
185 unsigned int resid_len; /* residual count */
188 unsigned long deadline;
189 struct list_head timeout_list;
190 unsigned int timeout;
194 * completion callback.
196 rq_end_io_fn *end_io;
200 struct request *next_rq;
203 static inline unsigned short req_get_ioprio(struct request *req)
208 #include <linux/elevator.h>
210 struct blk_queue_ctx;
212 typedef void (request_fn_proc) (struct request_queue *q);
213 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
214 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
215 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
218 typedef void (softirq_done_fn)(struct request *);
219 typedef int (dma_drain_needed_fn)(struct request *);
220 typedef int (lld_busy_fn) (struct request_queue *q);
221 typedef int (bsg_job_fn) (struct bsg_job *);
223 enum blk_eh_timer_return {
229 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
231 enum blk_queue_state {
236 struct blk_queue_tag {
237 struct request **tag_index; /* map of busy tags */
238 unsigned long *tag_map; /* bit map of free/busy tags */
239 int busy; /* current depth */
240 int max_depth; /* what we will send to device */
241 int real_max_depth; /* what the array can hold */
242 atomic_t refcnt; /* map can be shared */
243 int alloc_policy; /* tag allocation policy */
244 int next_tag; /* next tag */
246 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
247 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
249 #define BLK_SCSI_MAX_CMDS (256)
250 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
252 struct queue_limits {
253 unsigned long bounce_pfn;
254 unsigned long seg_boundary_mask;
255 unsigned long virt_boundary_mask;
257 unsigned int max_hw_sectors;
258 unsigned int max_dev_sectors;
259 unsigned int chunk_sectors;
260 unsigned int max_sectors;
261 unsigned int max_segment_size;
262 unsigned int physical_block_size;
263 unsigned int alignment_offset;
266 unsigned int max_discard_sectors;
267 unsigned int max_hw_discard_sectors;
268 unsigned int max_write_same_sectors;
269 unsigned int discard_granularity;
270 unsigned int discard_alignment;
272 unsigned short logical_block_size;
273 unsigned short max_segments;
274 unsigned short max_integrity_segments;
276 unsigned char misaligned;
277 unsigned char discard_misaligned;
278 unsigned char cluster;
279 unsigned char discard_zeroes_data;
280 unsigned char raid_partial_stripes_expensive;
283 struct request_queue {
285 * Together with queue_head for cacheline sharing
287 struct list_head queue_head;
288 struct request *last_merge;
289 struct elevator_queue *elevator;
290 int nr_rqs[2]; /* # allocated [a]sync rqs */
291 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
294 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
295 * is used, root blkg allocates from @q->root_rl and all other
296 * blkgs from their own blkg->rl. Which one to use should be
297 * determined using bio_request_list().
299 struct request_list root_rl;
301 request_fn_proc *request_fn;
302 make_request_fn *make_request_fn;
303 prep_rq_fn *prep_rq_fn;
304 unprep_rq_fn *unprep_rq_fn;
305 softirq_done_fn *softirq_done_fn;
306 rq_timed_out_fn *rq_timed_out_fn;
307 dma_drain_needed_fn *dma_drain_needed;
308 lld_busy_fn *lld_busy_fn;
310 struct blk_mq_ops *mq_ops;
312 unsigned int *mq_map;
315 struct blk_mq_ctx __percpu *queue_ctx;
316 unsigned int nr_queues;
318 /* hw dispatch queues */
319 struct blk_mq_hw_ctx **queue_hw_ctx;
320 unsigned int nr_hw_queues;
323 * Dispatch queue sorting
326 struct request *boundary_rq;
329 * Delayed queue handling
331 struct delayed_work delay_work;
333 struct backing_dev_info backing_dev_info;
336 * The queue owner gets to use this for whatever they like.
337 * ll_rw_blk doesn't touch it.
342 * various queue flags, see QUEUE_* below
344 unsigned long queue_flags;
347 * ida allocated id for this queue. Used to index queues from
353 * queue needs bounce pages for pages above this limit
358 * protects queue structures from reentrancy. ->__queue_lock should
359 * _never_ be used directly, it is queue private. always use
362 spinlock_t __queue_lock;
363 spinlock_t *queue_lock;
373 struct kobject mq_kobj;
375 #ifdef CONFIG_BLK_DEV_INTEGRITY
376 struct blk_integrity integrity;
377 #endif /* CONFIG_BLK_DEV_INTEGRITY */
382 unsigned int nr_pending;
388 unsigned long nr_requests; /* Max # of requests */
389 unsigned int nr_congestion_on;
390 unsigned int nr_congestion_off;
391 unsigned int nr_batching;
393 unsigned int dma_drain_size;
394 void *dma_drain_buffer;
395 unsigned int dma_pad_mask;
396 unsigned int dma_alignment;
398 struct blk_queue_tag *queue_tags;
399 struct list_head tag_busy_list;
401 unsigned int nr_sorted;
402 unsigned int in_flight[2];
404 * Number of active block driver functions for which blk_drain_queue()
405 * must wait. Must be incremented around functions that unlock the
406 * queue_lock internally, e.g. scsi_request_fn().
408 unsigned int request_fn_active;
410 unsigned int rq_timeout;
411 struct timer_list timeout;
412 struct list_head timeout_list;
414 struct list_head icq_list;
415 #ifdef CONFIG_BLK_CGROUP
416 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
417 struct blkcg_gq *root_blkg;
418 struct list_head blkg_list;
421 struct queue_limits limits;
426 unsigned int sg_timeout;
427 unsigned int sg_reserved_size;
429 #ifdef CONFIG_BLK_DEV_IO_TRACE
430 struct blk_trace *blk_trace;
433 * for flush operations
435 unsigned int flush_flags;
436 unsigned int flush_not_queueable:1;
437 struct blk_flush_queue *fq;
439 struct list_head requeue_list;
440 spinlock_t requeue_lock;
441 struct work_struct requeue_work;
443 struct mutex sysfs_lock;
446 atomic_t mq_freeze_depth;
448 #if defined(CONFIG_BLK_DEV_BSG)
449 bsg_job_fn *bsg_job_fn;
451 struct bsg_class_device bsg_dev;
454 #ifdef CONFIG_BLK_DEV_THROTTLING
456 struct throtl_data *td;
458 struct rcu_head rcu_head;
459 struct swait_queue_head mq_freeze_wq;
460 struct percpu_ref q_usage_counter;
461 struct list_head all_q_node;
463 struct blk_mq_tag_set *tag_set;
464 struct list_head tag_set_list;
465 struct bio_set *bio_split;
467 bool mq_sysfs_init_done;
470 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
471 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
472 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
473 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
474 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
475 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
476 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
477 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
478 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
479 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
480 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
481 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
482 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
483 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
484 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
485 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
486 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
487 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
488 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
489 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
490 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
491 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
492 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
494 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
495 (1 << QUEUE_FLAG_STACKABLE) | \
496 (1 << QUEUE_FLAG_SAME_COMP) | \
497 (1 << QUEUE_FLAG_ADD_RANDOM))
499 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
500 (1 << QUEUE_FLAG_STACKABLE) | \
501 (1 << QUEUE_FLAG_SAME_COMP))
503 static inline void queue_lockdep_assert_held(struct request_queue *q)
506 lockdep_assert_held(q->queue_lock);
509 static inline void queue_flag_set_unlocked(unsigned int flag,
510 struct request_queue *q)
512 __set_bit(flag, &q->queue_flags);
515 static inline int queue_flag_test_and_clear(unsigned int flag,
516 struct request_queue *q)
518 queue_lockdep_assert_held(q);
520 if (test_bit(flag, &q->queue_flags)) {
521 __clear_bit(flag, &q->queue_flags);
528 static inline int queue_flag_test_and_set(unsigned int flag,
529 struct request_queue *q)
531 queue_lockdep_assert_held(q);
533 if (!test_bit(flag, &q->queue_flags)) {
534 __set_bit(flag, &q->queue_flags);
541 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
543 queue_lockdep_assert_held(q);
544 __set_bit(flag, &q->queue_flags);
547 static inline void queue_flag_clear_unlocked(unsigned int flag,
548 struct request_queue *q)
550 __clear_bit(flag, &q->queue_flags);
553 static inline int queue_in_flight(struct request_queue *q)
555 return q->in_flight[0] + q->in_flight[1];
558 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
560 queue_lockdep_assert_held(q);
561 __clear_bit(flag, &q->queue_flags);
564 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
565 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
566 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
567 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
568 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
569 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
570 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
571 #define blk_queue_noxmerges(q) \
572 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
573 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
574 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
575 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
576 #define blk_queue_stackable(q) \
577 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
578 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
579 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
580 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
582 #define blk_noretry_request(rq) \
583 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
584 REQ_FAILFAST_DRIVER))
586 #define blk_account_rq(rq) \
587 (((rq)->cmd_flags & REQ_STARTED) && \
588 ((rq)->cmd_type == REQ_TYPE_FS))
590 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
591 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
592 /* rq->queuelist of dequeued request must be list_empty() */
593 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
595 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
597 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1))
600 * Driver can handle struct request, if it either has an old style
601 * request_fn defined, or is blk-mq based.
603 static inline bool queue_is_rq_based(struct request_queue *q)
605 return q->request_fn || q->mq_ops;
608 static inline unsigned int blk_queue_cluster(struct request_queue *q)
610 return q->limits.cluster;
614 * We regard a request as sync, if either a read or a sync write
616 static inline bool rw_is_sync(unsigned int rw_flags)
618 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
621 static inline bool rq_is_sync(struct request *rq)
623 return rw_is_sync(rq->cmd_flags);
626 static inline bool blk_rl_full(struct request_list *rl, bool sync)
628 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
630 return rl->flags & flag;
633 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
635 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
640 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
642 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
647 static inline bool rq_mergeable(struct request *rq)
649 if (rq->cmd_type != REQ_TYPE_FS)
652 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
658 static inline bool blk_check_merge_flags(unsigned int flags1,
661 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
664 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
667 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
673 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
675 if (bio_data(a) == bio_data(b))
682 * q->prep_rq_fn return values
684 #define BLKPREP_OK 0 /* serve it */
685 #define BLKPREP_KILL 1 /* fatal error, kill */
686 #define BLKPREP_DEFER 2 /* leave on queue */
688 extern unsigned long blk_max_low_pfn, blk_max_pfn;
691 * standard bounce addresses:
693 * BLK_BOUNCE_HIGH : bounce all highmem pages
694 * BLK_BOUNCE_ANY : don't bounce anything
695 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
698 #if BITS_PER_LONG == 32
699 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
701 #define BLK_BOUNCE_HIGH -1ULL
703 #define BLK_BOUNCE_ANY (-1ULL)
704 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
707 * default timeout for SG_IO if none specified
709 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
710 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
713 extern int init_emergency_isa_pool(void);
714 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
716 static inline int init_emergency_isa_pool(void)
720 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
723 #endif /* CONFIG_MMU */
729 unsigned long offset;
734 struct req_iterator {
735 struct bvec_iter iter;
739 /* This should not be used directly - use rq_for_each_segment */
740 #define for_each_bio(_bio) \
741 for (; _bio; _bio = _bio->bi_next)
742 #define __rq_for_each_bio(_bio, rq) \
744 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
746 #define rq_for_each_segment(bvl, _rq, _iter) \
747 __rq_for_each_bio(_iter.bio, _rq) \
748 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
750 #define rq_iter_last(bvec, _iter) \
751 (_iter.bio->bi_next == NULL && \
752 bio_iter_last(bvec, _iter.iter))
754 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
755 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
757 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
758 extern void rq_flush_dcache_pages(struct request *rq);
760 static inline void rq_flush_dcache_pages(struct request *rq)
765 extern int blk_register_queue(struct gendisk *disk);
766 extern void blk_unregister_queue(struct gendisk *disk);
767 extern blk_qc_t generic_make_request(struct bio *bio);
768 extern void blk_rq_init(struct request_queue *q, struct request *rq);
769 extern void blk_put_request(struct request *);
770 extern void __blk_put_request(struct request_queue *, struct request *);
771 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
772 extern struct request *blk_make_request(struct request_queue *, struct bio *,
774 extern void blk_rq_set_block_pc(struct request *);
775 extern void blk_requeue_request(struct request_queue *, struct request *);
776 extern void blk_add_request_payload(struct request *rq, struct page *page,
778 extern int blk_lld_busy(struct request_queue *q);
779 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
780 struct bio_set *bs, gfp_t gfp_mask,
781 int (*bio_ctr)(struct bio *, struct bio *, void *),
783 extern void blk_rq_unprep_clone(struct request *rq);
784 extern int blk_insert_cloned_request(struct request_queue *q,
786 extern void blk_delay_queue(struct request_queue *, unsigned long);
787 extern void blk_queue_split(struct request_queue *, struct bio **,
789 extern void blk_recount_segments(struct request_queue *, struct bio *);
790 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
791 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
792 unsigned int, void __user *);
793 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
794 unsigned int, void __user *);
795 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
796 struct scsi_ioctl_command __user *);
798 extern int blk_queue_enter(struct request_queue *q, gfp_t gfp);
799 extern void blk_queue_exit(struct request_queue *q);
800 extern void blk_start_queue(struct request_queue *q);
801 extern void blk_start_queue_async(struct request_queue *q);
802 extern void blk_stop_queue(struct request_queue *q);
803 extern void blk_sync_queue(struct request_queue *q);
804 extern void __blk_stop_queue(struct request_queue *q);
805 extern void __blk_run_queue(struct request_queue *q);
806 extern void __blk_run_queue_uncond(struct request_queue *q);
807 extern void blk_run_queue(struct request_queue *);
808 extern void blk_run_queue_async(struct request_queue *q);
809 extern int blk_rq_map_user(struct request_queue *, struct request *,
810 struct rq_map_data *, void __user *, unsigned long,
812 extern int blk_rq_unmap_user(struct bio *);
813 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
814 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
815 struct rq_map_data *, const struct iov_iter *,
817 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
818 struct request *, int);
819 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
820 struct request *, int, rq_end_io_fn *);
822 bool blk_poll(struct request_queue *q, blk_qc_t cookie);
824 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
826 return bdev->bd_disk->queue; /* this is never NULL */
830 * blk_rq_pos() : the current sector
831 * blk_rq_bytes() : bytes left in the entire request
832 * blk_rq_cur_bytes() : bytes left in the current segment
833 * blk_rq_err_bytes() : bytes left till the next error boundary
834 * blk_rq_sectors() : sectors left in the entire request
835 * blk_rq_cur_sectors() : sectors left in the current segment
837 static inline sector_t blk_rq_pos(const struct request *rq)
842 static inline unsigned int blk_rq_bytes(const struct request *rq)
844 return rq->__data_len;
847 static inline int blk_rq_cur_bytes(const struct request *rq)
849 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
852 extern unsigned int blk_rq_err_bytes(const struct request *rq);
854 static inline unsigned int blk_rq_sectors(const struct request *rq)
856 return blk_rq_bytes(rq) >> 9;
859 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
861 return blk_rq_cur_bytes(rq) >> 9;
864 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
865 unsigned int cmd_flags)
867 if (unlikely(cmd_flags & REQ_DISCARD))
868 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
870 if (unlikely(cmd_flags & REQ_WRITE_SAME))
871 return q->limits.max_write_same_sectors;
873 return q->limits.max_sectors;
877 * Return maximum size of a request at given offset. Only valid for
878 * file system requests.
880 static inline unsigned int blk_max_size_offset(struct request_queue *q,
883 if (!q->limits.chunk_sectors)
884 return q->limits.max_sectors;
886 return q->limits.chunk_sectors -
887 (offset & (q->limits.chunk_sectors - 1));
890 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
892 struct request_queue *q = rq->q;
894 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
895 return q->limits.max_hw_sectors;
897 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD))
898 return blk_queue_get_max_sectors(q, rq->cmd_flags);
900 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
901 blk_queue_get_max_sectors(q, rq->cmd_flags));
904 static inline unsigned int blk_rq_count_bios(struct request *rq)
906 unsigned int nr_bios = 0;
909 __rq_for_each_bio(bio, rq)
916 * Request issue related functions.
918 extern struct request *blk_peek_request(struct request_queue *q);
919 extern void blk_start_request(struct request *rq);
920 extern struct request *blk_fetch_request(struct request_queue *q);
923 * Request completion related functions.
925 * blk_update_request() completes given number of bytes and updates
926 * the request without completing it.
928 * blk_end_request() and friends. __blk_end_request() must be called
929 * with the request queue spinlock acquired.
931 * Several drivers define their own end_request and call
932 * blk_end_request() for parts of the original function.
933 * This prevents code duplication in drivers.
935 extern bool blk_update_request(struct request *rq, int error,
936 unsigned int nr_bytes);
937 extern void blk_finish_request(struct request *rq, int error);
938 extern bool blk_end_request(struct request *rq, int error,
939 unsigned int nr_bytes);
940 extern void blk_end_request_all(struct request *rq, int error);
941 extern bool blk_end_request_cur(struct request *rq, int error);
942 extern bool blk_end_request_err(struct request *rq, int error);
943 extern bool __blk_end_request(struct request *rq, int error,
944 unsigned int nr_bytes);
945 extern void __blk_end_request_all(struct request *rq, int error);
946 extern bool __blk_end_request_cur(struct request *rq, int error);
947 extern bool __blk_end_request_err(struct request *rq, int error);
949 extern void blk_complete_request(struct request *);
950 extern void __blk_complete_request(struct request *);
951 extern void blk_abort_request(struct request *);
952 extern void blk_unprep_request(struct request *);
955 * Access functions for manipulating queue properties
957 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
958 spinlock_t *lock, int node_id);
959 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
960 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
961 request_fn_proc *, spinlock_t *);
962 extern void blk_cleanup_queue(struct request_queue *);
963 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
964 extern void blk_queue_bounce_limit(struct request_queue *, u64);
965 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
966 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
967 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
968 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
969 extern void blk_queue_max_discard_sectors(struct request_queue *q,
970 unsigned int max_discard_sectors);
971 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
972 unsigned int max_write_same_sectors);
973 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
974 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
975 extern void blk_queue_alignment_offset(struct request_queue *q,
976 unsigned int alignment);
977 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
978 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
979 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
980 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
981 extern void blk_set_default_limits(struct queue_limits *lim);
982 extern void blk_set_stacking_limits(struct queue_limits *lim);
983 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
985 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
987 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
989 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
990 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
991 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
992 extern int blk_queue_dma_drain(struct request_queue *q,
993 dma_drain_needed_fn *dma_drain_needed,
994 void *buf, unsigned int size);
995 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
996 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
997 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
998 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
999 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1000 extern void blk_queue_dma_alignment(struct request_queue *, int);
1001 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1002 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1003 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1004 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1005 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
1006 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1007 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1009 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1010 extern void blk_dump_rq_flags(struct request *, char *);
1011 extern long nr_blockdev_pages(void);
1013 bool __must_check blk_get_queue(struct request_queue *);
1014 struct request_queue *blk_alloc_queue(gfp_t);
1015 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1016 extern void blk_put_queue(struct request_queue *);
1017 extern void blk_set_queue_dying(struct request_queue *);
1020 * block layer runtime pm functions
1023 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1024 extern int blk_pre_runtime_suspend(struct request_queue *q);
1025 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1026 extern void blk_pre_runtime_resume(struct request_queue *q);
1027 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1029 static inline void blk_pm_runtime_init(struct request_queue *q,
1030 struct device *dev) {}
1031 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1035 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1036 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1037 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1041 * blk_plug permits building a queue of related requests by holding the I/O
1042 * fragments for a short period. This allows merging of sequential requests
1043 * into single larger request. As the requests are moved from a per-task list to
1044 * the device's request_queue in a batch, this results in improved scalability
1045 * as the lock contention for request_queue lock is reduced.
1047 * It is ok not to disable preemption when adding the request to the plug list
1048 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1049 * the plug list when the task sleeps by itself. For details, please see
1050 * schedule() where blk_schedule_flush_plug() is called.
1053 struct list_head list; /* requests */
1054 struct list_head mq_list; /* blk-mq requests */
1055 struct list_head cb_list; /* md requires an unplug callback */
1057 #define BLK_MAX_REQUEST_COUNT 16
1060 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1061 struct blk_plug_cb {
1062 struct list_head list;
1063 blk_plug_cb_fn callback;
1066 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1067 void *data, int size);
1068 extern void blk_start_plug(struct blk_plug *);
1069 extern void blk_finish_plug(struct blk_plug *);
1070 extern void blk_flush_plug_list(struct blk_plug *, bool);
1072 static inline void blk_flush_plug(struct task_struct *tsk)
1074 struct blk_plug *plug = tsk->plug;
1077 blk_flush_plug_list(plug, false);
1080 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1082 struct blk_plug *plug = tsk->plug;
1085 blk_flush_plug_list(plug, true);
1088 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1090 struct blk_plug *plug = tsk->plug;
1093 (!list_empty(&plug->list) ||
1094 !list_empty(&plug->mq_list) ||
1095 !list_empty(&plug->cb_list));
1101 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1102 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1103 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1104 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1105 extern void blk_queue_free_tags(struct request_queue *);
1106 extern int blk_queue_resize_tags(struct request_queue *, int);
1107 extern void blk_queue_invalidate_tags(struct request_queue *);
1108 extern struct blk_queue_tag *blk_init_tags(int, int);
1109 extern void blk_free_tags(struct blk_queue_tag *);
1111 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1114 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1116 return bqt->tag_index[tag];
1119 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1121 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1122 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1123 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1124 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1125 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1126 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1127 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1128 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1129 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1131 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1132 nr_blocks << (sb->s_blocksize_bits - 9),
1135 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1136 sector_t nr_blocks, gfp_t gfp_mask)
1138 return blkdev_issue_zeroout(sb->s_bdev,
1139 block << (sb->s_blocksize_bits - 9),
1140 nr_blocks << (sb->s_blocksize_bits - 9),
1144 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1146 enum blk_default_limits {
1147 BLK_MAX_SEGMENTS = 128,
1148 BLK_SAFE_MAX_SECTORS = 255,
1149 BLK_DEF_MAX_SECTORS = 2560,
1150 BLK_MAX_SEGMENT_SIZE = 65536,
1151 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1154 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1156 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1158 return q->limits.bounce_pfn;
1161 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1163 return q->limits.seg_boundary_mask;
1166 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1168 return q->limits.virt_boundary_mask;
1171 static inline unsigned int queue_max_sectors(struct request_queue *q)
1173 return q->limits.max_sectors;
1176 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1178 return q->limits.max_hw_sectors;
1181 static inline unsigned short queue_max_segments(struct request_queue *q)
1183 return q->limits.max_segments;
1186 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1188 return q->limits.max_segment_size;
1191 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1195 if (q && q->limits.logical_block_size)
1196 retval = q->limits.logical_block_size;
1201 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1203 return queue_logical_block_size(bdev_get_queue(bdev));
1206 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1208 return q->limits.physical_block_size;
1211 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1213 return queue_physical_block_size(bdev_get_queue(bdev));
1216 static inline unsigned int queue_io_min(struct request_queue *q)
1218 return q->limits.io_min;
1221 static inline int bdev_io_min(struct block_device *bdev)
1223 return queue_io_min(bdev_get_queue(bdev));
1226 static inline unsigned int queue_io_opt(struct request_queue *q)
1228 return q->limits.io_opt;
1231 static inline int bdev_io_opt(struct block_device *bdev)
1233 return queue_io_opt(bdev_get_queue(bdev));
1236 static inline int queue_alignment_offset(struct request_queue *q)
1238 if (q->limits.misaligned)
1241 return q->limits.alignment_offset;
1244 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1246 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1247 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1249 return (granularity + lim->alignment_offset - alignment) % granularity;
1252 static inline int bdev_alignment_offset(struct block_device *bdev)
1254 struct request_queue *q = bdev_get_queue(bdev);
1256 if (q->limits.misaligned)
1259 if (bdev != bdev->bd_contains)
1260 return bdev->bd_part->alignment_offset;
1262 return q->limits.alignment_offset;
1265 static inline int queue_discard_alignment(struct request_queue *q)
1267 if (q->limits.discard_misaligned)
1270 return q->limits.discard_alignment;
1273 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1275 unsigned int alignment, granularity, offset;
1277 if (!lim->max_discard_sectors)
1280 /* Why are these in bytes, not sectors? */
1281 alignment = lim->discard_alignment >> 9;
1282 granularity = lim->discard_granularity >> 9;
1286 /* Offset of the partition start in 'granularity' sectors */
1287 offset = sector_div(sector, granularity);
1289 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1290 offset = (granularity + alignment - offset) % granularity;
1292 /* Turn it back into bytes, gaah */
1296 static inline int bdev_discard_alignment(struct block_device *bdev)
1298 struct request_queue *q = bdev_get_queue(bdev);
1300 if (bdev != bdev->bd_contains)
1301 return bdev->bd_part->discard_alignment;
1303 return q->limits.discard_alignment;
1306 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1308 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1314 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1316 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1319 static inline unsigned int bdev_write_same(struct block_device *bdev)
1321 struct request_queue *q = bdev_get_queue(bdev);
1324 return q->limits.max_write_same_sectors;
1329 static inline int queue_dma_alignment(struct request_queue *q)
1331 return q ? q->dma_alignment : 511;
1334 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1337 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1338 return !(addr & alignment) && !(len & alignment);
1341 /* assumes size > 256 */
1342 static inline unsigned int blksize_bits(unsigned int size)
1344 unsigned int bits = 8;
1348 } while (size > 256);
1352 static inline unsigned int block_size(struct block_device *bdev)
1354 return bdev->bd_block_size;
1357 static inline bool queue_flush_queueable(struct request_queue *q)
1359 return !q->flush_not_queueable;
1362 typedef struct {struct page *v;} Sector;
1364 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1366 static inline void put_dev_sector(Sector p)
1368 page_cache_release(p.v);
1371 static inline bool __bvec_gap_to_prev(struct request_queue *q,
1372 struct bio_vec *bprv, unsigned int offset)
1375 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1379 * Check if adding a bio_vec after bprv with offset would create a gap in
1380 * the SG list. Most drivers don't care about this, but some do.
1382 static inline bool bvec_gap_to_prev(struct request_queue *q,
1383 struct bio_vec *bprv, unsigned int offset)
1385 if (!queue_virt_boundary(q))
1387 return __bvec_gap_to_prev(q, bprv, offset);
1390 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1393 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1394 struct bio_vec pb, nb;
1396 bio_get_last_bvec(prev, &pb);
1397 bio_get_first_bvec(next, &nb);
1399 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1405 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1407 return bio_will_gap(req->q, req->biotail, bio);
1410 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1412 return bio_will_gap(req->q, bio, req->bio);
1416 int kblockd_schedule_work(struct work_struct *work);
1417 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1418 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1420 #ifdef CONFIG_BLK_CGROUP
1422 * This should not be using sched_clock(). A real patch is in progress
1423 * to fix this up, until that is in place we need to disable preemption
1424 * around sched_clock() in this function and set_io_start_time_ns().
1426 static inline void set_start_time_ns(struct request *req)
1429 req->start_time_ns = sched_clock();
1433 static inline void set_io_start_time_ns(struct request *req)
1436 req->io_start_time_ns = sched_clock();
1440 static inline uint64_t rq_start_time_ns(struct request *req)
1442 return req->start_time_ns;
1445 static inline uint64_t rq_io_start_time_ns(struct request *req)
1447 return req->io_start_time_ns;
1450 static inline void set_start_time_ns(struct request *req) {}
1451 static inline void set_io_start_time_ns(struct request *req) {}
1452 static inline uint64_t rq_start_time_ns(struct request *req)
1456 static inline uint64_t rq_io_start_time_ns(struct request *req)
1462 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1463 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1464 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1465 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1467 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1469 enum blk_integrity_flags {
1470 BLK_INTEGRITY_VERIFY = 1 << 0,
1471 BLK_INTEGRITY_GENERATE = 1 << 1,
1472 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1473 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1476 struct blk_integrity_iter {
1480 unsigned int data_size;
1481 unsigned short interval;
1482 const char *disk_name;
1485 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1487 struct blk_integrity_profile {
1488 integrity_processing_fn *generate_fn;
1489 integrity_processing_fn *verify_fn;
1493 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1494 extern void blk_integrity_unregister(struct gendisk *);
1495 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1496 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1497 struct scatterlist *);
1498 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1499 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1501 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1504 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1506 struct blk_integrity *bi = &disk->queue->integrity;
1515 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1517 return blk_get_integrity(bdev->bd_disk);
1520 static inline bool blk_integrity_rq(struct request *rq)
1522 return rq->cmd_flags & REQ_INTEGRITY;
1525 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1528 q->limits.max_integrity_segments = segs;
1531 static inline unsigned short
1532 queue_max_integrity_segments(struct request_queue *q)
1534 return q->limits.max_integrity_segments;
1537 static inline bool integrity_req_gap_back_merge(struct request *req,
1540 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1541 struct bio_integrity_payload *bip_next = bio_integrity(next);
1543 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1544 bip_next->bip_vec[0].bv_offset);
1547 static inline bool integrity_req_gap_front_merge(struct request *req,
1550 struct bio_integrity_payload *bip = bio_integrity(bio);
1551 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1553 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1554 bip_next->bip_vec[0].bv_offset);
1557 #else /* CONFIG_BLK_DEV_INTEGRITY */
1560 struct block_device;
1562 struct blk_integrity;
1564 static inline int blk_integrity_rq(struct request *rq)
1568 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1573 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1575 struct scatterlist *s)
1579 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1583 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1587 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1591 static inline void blk_integrity_register(struct gendisk *d,
1592 struct blk_integrity *b)
1595 static inline void blk_integrity_unregister(struct gendisk *d)
1598 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1602 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1606 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1612 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1619 static inline bool integrity_req_gap_back_merge(struct request *req,
1624 static inline bool integrity_req_gap_front_merge(struct request *req,
1630 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1632 struct block_device_operations {
1633 int (*open) (struct block_device *, fmode_t);
1634 void (*release) (struct gendisk *, fmode_t);
1635 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1636 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1637 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1638 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
1639 unsigned long *pfn);
1640 unsigned int (*check_events) (struct gendisk *disk,
1641 unsigned int clearing);
1642 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1643 int (*media_changed) (struct gendisk *);
1644 void (*unlock_native_capacity) (struct gendisk *);
1645 int (*revalidate_disk) (struct gendisk *);
1646 int (*getgeo)(struct block_device *, struct hd_geometry *);
1647 /* this callback is with swap_lock and sometimes page table lock held */
1648 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1649 struct module *owner;
1650 const struct pr_ops *pr_ops;
1653 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1655 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1656 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1657 struct writeback_control *);
1658 extern long bdev_direct_access(struct block_device *, sector_t,
1659 void __pmem **addr, unsigned long *pfn, long size);
1660 #else /* CONFIG_BLOCK */
1662 struct block_device;
1665 * stubs for when the block layer is configured out
1667 #define buffer_heads_over_limit 0
1669 static inline long nr_blockdev_pages(void)
1677 static inline void blk_start_plug(struct blk_plug *plug)
1681 static inline void blk_finish_plug(struct blk_plug *plug)
1685 static inline void blk_flush_plug(struct task_struct *task)
1689 static inline void blk_schedule_flush_plug(struct task_struct *task)
1694 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1699 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1700 sector_t *error_sector)
1705 #endif /* CONFIG_BLOCK */