1 #ifndef _LINUX_BLKDEV_H
2 #define _LINUX_BLKDEV_H
4 #include <linux/sched.h>
8 #include <linux/major.h>
9 #include <linux/genhd.h>
10 #include <linux/list.h>
11 #include <linux/llist.h>
12 #include <linux/timer.h>
13 #include <linux/workqueue.h>
14 #include <linux/pagemap.h>
15 #include <linux/backing-dev-defs.h>
16 #include <linux/wait.h>
17 #include <linux/mempool.h>
18 #include <linux/pfn.h>
19 #include <linux/bio.h>
20 #include <linux/stringify.h>
21 #include <linux/gfp.h>
22 #include <linux/bsg.h>
23 #include <linux/smp.h>
24 #include <linux/rcupdate.h>
25 #include <linux/percpu-refcount.h>
26 #include <linux/scatterlist.h>
29 struct scsi_ioctl_command;
32 struct elevator_queue;
38 struct blk_flush_queue;
41 #define BLKDEV_MIN_RQ 4
42 #define BLKDEV_MAX_RQ 128 /* Default maximum */
45 * Maximum number of blkcg policies allowed to be registered concurrently.
46 * Defined here to simplify include dependency.
48 #define BLKCG_MAX_POLS 2
51 typedef void (rq_end_io_fn)(struct request *, int);
53 #define BLK_RL_SYNCFULL (1U << 0)
54 #define BLK_RL_ASYNCFULL (1U << 1)
57 struct request_queue *q; /* the queue this rl belongs to */
58 #ifdef CONFIG_BLK_CGROUP
59 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
62 * count[], starved[], and wait[] are indexed by
63 * BLK_RW_SYNC/BLK_RW_ASYNC
68 wait_queue_head_t wait[2];
73 * request command types
75 enum rq_cmd_type_bits {
76 REQ_TYPE_FS = 1, /* fs request */
77 REQ_TYPE_BLOCK_PC, /* scsi command */
78 REQ_TYPE_DRV_PRIV, /* driver defined types from here */
81 #define BLK_MAX_CDB 16
84 * Try to put the fields that are referenced together in the same cacheline.
86 * If you modify this structure, make sure to update blk_rq_init() and
87 * especially blk_mq_rq_ctx_init() to take care of the added fields.
90 struct list_head queuelist;
92 struct call_single_data csd;
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 #define REQ_OP_SHIFT (8 * sizeof(u64) - REQ_OP_BITS)
204 #define req_op(req) ((req)->cmd_flags >> REQ_OP_SHIFT)
206 #define req_set_op(req, op) do { \
207 WARN_ON(op >= (1 << REQ_OP_BITS)); \
208 (req)->cmd_flags &= ((1ULL << REQ_OP_SHIFT) - 1); \
209 (req)->cmd_flags |= ((u64) (op) << REQ_OP_SHIFT); \
212 #define req_set_op_attrs(req, op, flags) do { \
213 req_set_op(req, op); \
214 (req)->cmd_flags |= flags; \
217 static inline unsigned short req_get_ioprio(struct request *req)
222 #include <linux/elevator.h>
224 struct blk_queue_ctx;
226 typedef void (request_fn_proc) (struct request_queue *q);
227 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
228 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
229 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
232 typedef void (softirq_done_fn)(struct request *);
233 typedef int (dma_drain_needed_fn)(struct request *);
234 typedef int (lld_busy_fn) (struct request_queue *q);
235 typedef int (bsg_job_fn) (struct bsg_job *);
237 enum blk_eh_timer_return {
243 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
245 enum blk_queue_state {
250 struct blk_queue_tag {
251 struct request **tag_index; /* map of busy tags */
252 unsigned long *tag_map; /* bit map of free/busy tags */
253 int busy; /* current depth */
254 int max_depth; /* what we will send to device */
255 int real_max_depth; /* what the array can hold */
256 atomic_t refcnt; /* map can be shared */
257 int alloc_policy; /* tag allocation policy */
258 int next_tag; /* next tag */
260 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
261 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
263 #define BLK_SCSI_MAX_CMDS (256)
264 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
266 struct queue_limits {
267 unsigned long bounce_pfn;
268 unsigned long seg_boundary_mask;
269 unsigned long virt_boundary_mask;
271 unsigned int max_hw_sectors;
272 unsigned int max_dev_sectors;
273 unsigned int chunk_sectors;
274 unsigned int max_sectors;
275 unsigned int max_segment_size;
276 unsigned int physical_block_size;
277 unsigned int alignment_offset;
280 unsigned int max_discard_sectors;
281 unsigned int max_hw_discard_sectors;
282 unsigned int max_write_same_sectors;
283 unsigned int discard_granularity;
284 unsigned int discard_alignment;
286 unsigned short logical_block_size;
287 unsigned short max_segments;
288 unsigned short max_integrity_segments;
290 unsigned char misaligned;
291 unsigned char discard_misaligned;
292 unsigned char cluster;
293 unsigned char discard_zeroes_data;
294 unsigned char raid_partial_stripes_expensive;
297 struct request_queue {
299 * Together with queue_head for cacheline sharing
301 struct list_head queue_head;
302 struct request *last_merge;
303 struct elevator_queue *elevator;
304 int nr_rqs[2]; /* # allocated [a]sync rqs */
305 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
308 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
309 * is used, root blkg allocates from @q->root_rl and all other
310 * blkgs from their own blkg->rl. Which one to use should be
311 * determined using bio_request_list().
313 struct request_list root_rl;
315 request_fn_proc *request_fn;
316 make_request_fn *make_request_fn;
317 prep_rq_fn *prep_rq_fn;
318 unprep_rq_fn *unprep_rq_fn;
319 softirq_done_fn *softirq_done_fn;
320 rq_timed_out_fn *rq_timed_out_fn;
321 dma_drain_needed_fn *dma_drain_needed;
322 lld_busy_fn *lld_busy_fn;
324 struct blk_mq_ops *mq_ops;
326 unsigned int *mq_map;
329 struct blk_mq_ctx __percpu *queue_ctx;
330 unsigned int nr_queues;
332 /* hw dispatch queues */
333 struct blk_mq_hw_ctx **queue_hw_ctx;
334 unsigned int nr_hw_queues;
337 * Dispatch queue sorting
340 struct request *boundary_rq;
343 * Delayed queue handling
345 struct delayed_work delay_work;
347 struct backing_dev_info backing_dev_info;
350 * The queue owner gets to use this for whatever they like.
351 * ll_rw_blk doesn't touch it.
356 * various queue flags, see QUEUE_* below
358 unsigned long queue_flags;
361 * ida allocated id for this queue. Used to index queues from
367 * queue needs bounce pages for pages above this limit
372 * protects queue structures from reentrancy. ->__queue_lock should
373 * _never_ be used directly, it is queue private. always use
376 spinlock_t __queue_lock;
377 spinlock_t *queue_lock;
387 struct kobject mq_kobj;
389 #ifdef CONFIG_BLK_DEV_INTEGRITY
390 struct blk_integrity integrity;
391 #endif /* CONFIG_BLK_DEV_INTEGRITY */
396 unsigned int nr_pending;
402 unsigned long nr_requests; /* Max # of requests */
403 unsigned int nr_congestion_on;
404 unsigned int nr_congestion_off;
405 unsigned int nr_batching;
407 unsigned int dma_drain_size;
408 void *dma_drain_buffer;
409 unsigned int dma_pad_mask;
410 unsigned int dma_alignment;
412 struct blk_queue_tag *queue_tags;
413 struct list_head tag_busy_list;
415 unsigned int nr_sorted;
416 unsigned int in_flight[2];
418 * Number of active block driver functions for which blk_drain_queue()
419 * must wait. Must be incremented around functions that unlock the
420 * queue_lock internally, e.g. scsi_request_fn().
422 unsigned int request_fn_active;
424 unsigned int rq_timeout;
425 struct timer_list timeout;
426 struct work_struct timeout_work;
427 struct list_head timeout_list;
429 struct list_head icq_list;
430 #ifdef CONFIG_BLK_CGROUP
431 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
432 struct blkcg_gq *root_blkg;
433 struct list_head blkg_list;
436 struct queue_limits limits;
441 unsigned int sg_timeout;
442 unsigned int sg_reserved_size;
444 #ifdef CONFIG_BLK_DEV_IO_TRACE
445 struct blk_trace *blk_trace;
448 * for flush operations
450 struct blk_flush_queue *fq;
452 struct list_head requeue_list;
453 spinlock_t requeue_lock;
454 struct work_struct requeue_work;
456 struct mutex sysfs_lock;
459 atomic_t mq_freeze_depth;
461 #if defined(CONFIG_BLK_DEV_BSG)
462 bsg_job_fn *bsg_job_fn;
464 struct bsg_class_device bsg_dev;
467 #ifdef CONFIG_BLK_DEV_THROTTLING
469 struct throtl_data *td;
471 struct rcu_head rcu_head;
472 wait_queue_head_t mq_freeze_wq;
473 struct percpu_ref q_usage_counter;
474 struct list_head all_q_node;
476 struct blk_mq_tag_set *tag_set;
477 struct list_head tag_set_list;
478 struct bio_set *bio_split;
480 bool mq_sysfs_init_done;
483 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
484 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
485 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
486 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
487 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
488 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
489 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
490 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
491 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
492 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
493 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
494 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
495 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
496 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
497 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
498 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
499 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
500 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
501 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
502 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
503 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
504 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
505 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
506 #define QUEUE_FLAG_WC 23 /* Write back caching */
507 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
508 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
510 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
511 (1 << QUEUE_FLAG_STACKABLE) | \
512 (1 << QUEUE_FLAG_SAME_COMP) | \
513 (1 << QUEUE_FLAG_ADD_RANDOM))
515 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
516 (1 << QUEUE_FLAG_STACKABLE) | \
517 (1 << QUEUE_FLAG_SAME_COMP) | \
518 (1 << QUEUE_FLAG_POLL))
520 static inline void queue_lockdep_assert_held(struct request_queue *q)
523 lockdep_assert_held(q->queue_lock);
526 static inline void queue_flag_set_unlocked(unsigned int flag,
527 struct request_queue *q)
529 __set_bit(flag, &q->queue_flags);
532 static inline int queue_flag_test_and_clear(unsigned int flag,
533 struct request_queue *q)
535 queue_lockdep_assert_held(q);
537 if (test_bit(flag, &q->queue_flags)) {
538 __clear_bit(flag, &q->queue_flags);
545 static inline int queue_flag_test_and_set(unsigned int flag,
546 struct request_queue *q)
548 queue_lockdep_assert_held(q);
550 if (!test_bit(flag, &q->queue_flags)) {
551 __set_bit(flag, &q->queue_flags);
558 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
560 queue_lockdep_assert_held(q);
561 __set_bit(flag, &q->queue_flags);
564 static inline void queue_flag_clear_unlocked(unsigned int flag,
565 struct request_queue *q)
567 __clear_bit(flag, &q->queue_flags);
570 static inline int queue_in_flight(struct request_queue *q)
572 return q->in_flight[0] + q->in_flight[1];
575 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
577 queue_lockdep_assert_held(q);
578 __clear_bit(flag, &q->queue_flags);
581 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
582 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
583 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
584 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
585 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
586 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
587 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
588 #define blk_queue_noxmerges(q) \
589 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
590 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
591 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
592 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
593 #define blk_queue_stackable(q) \
594 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
595 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
596 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
597 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
599 #define blk_noretry_request(rq) \
600 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
601 REQ_FAILFAST_DRIVER))
603 #define blk_account_rq(rq) \
604 (((rq)->cmd_flags & REQ_STARTED) && \
605 ((rq)->cmd_type == REQ_TYPE_FS))
607 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
608 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
609 /* rq->queuelist of dequeued request must be list_empty() */
610 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
612 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
614 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
617 * Driver can handle struct request, if it either has an old style
618 * request_fn defined, or is blk-mq based.
620 static inline bool queue_is_rq_based(struct request_queue *q)
622 return q->request_fn || q->mq_ops;
625 static inline unsigned int blk_queue_cluster(struct request_queue *q)
627 return q->limits.cluster;
631 * We regard a request as sync, if either a read or a sync write
633 static inline bool rw_is_sync(int op, unsigned int rw_flags)
635 return op == REQ_OP_READ || (rw_flags & REQ_SYNC);
638 static inline bool rq_is_sync(struct request *rq)
640 return rw_is_sync(req_op(rq), rq->cmd_flags);
643 static inline bool blk_rl_full(struct request_list *rl, bool sync)
645 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
647 return rl->flags & flag;
650 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
652 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
657 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
659 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
664 static inline bool rq_mergeable(struct request *rq)
666 if (rq->cmd_type != REQ_TYPE_FS)
669 if (req_op(rq) == REQ_OP_FLUSH)
672 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
678 static inline bool blk_check_merge_flags(unsigned int flags1, unsigned int op1,
679 unsigned int flags2, unsigned int op2)
681 if ((op1 == REQ_OP_DISCARD) != (op2 == REQ_OP_DISCARD))
684 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
687 if ((op1 == REQ_OP_WRITE_SAME) != (op2 == REQ_OP_WRITE_SAME))
693 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
695 if (bio_data(a) == bio_data(b))
702 * q->prep_rq_fn return values
705 BLKPREP_OK, /* serve it */
706 BLKPREP_KILL, /* fatal error, kill, return -EIO */
707 BLKPREP_DEFER, /* leave on queue */
708 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */
711 extern unsigned long blk_max_low_pfn, blk_max_pfn;
714 * standard bounce addresses:
716 * BLK_BOUNCE_HIGH : bounce all highmem pages
717 * BLK_BOUNCE_ANY : don't bounce anything
718 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
721 #if BITS_PER_LONG == 32
722 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
724 #define BLK_BOUNCE_HIGH -1ULL
726 #define BLK_BOUNCE_ANY (-1ULL)
727 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
730 * default timeout for SG_IO if none specified
732 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
733 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
736 extern int init_emergency_isa_pool(void);
737 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
739 static inline int init_emergency_isa_pool(void)
743 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
746 #endif /* CONFIG_MMU */
752 unsigned long offset;
757 struct req_iterator {
758 struct bvec_iter iter;
762 /* This should not be used directly - use rq_for_each_segment */
763 #define for_each_bio(_bio) \
764 for (; _bio; _bio = _bio->bi_next)
765 #define __rq_for_each_bio(_bio, rq) \
767 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
769 #define rq_for_each_segment(bvl, _rq, _iter) \
770 __rq_for_each_bio(_iter.bio, _rq) \
771 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
773 #define rq_iter_last(bvec, _iter) \
774 (_iter.bio->bi_next == NULL && \
775 bio_iter_last(bvec, _iter.iter))
777 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
778 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
780 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
781 extern void rq_flush_dcache_pages(struct request *rq);
783 static inline void rq_flush_dcache_pages(struct request *rq)
789 #define vfs_msg(sb, level, fmt, ...) \
790 __vfs_msg(sb, level, fmt, ##__VA_ARGS__)
792 #define vfs_msg(sb, level, fmt, ...) \
794 no_printk(fmt, ##__VA_ARGS__); \
795 __vfs_msg(sb, "", " "); \
799 extern int blk_register_queue(struct gendisk *disk);
800 extern void blk_unregister_queue(struct gendisk *disk);
801 extern blk_qc_t generic_make_request(struct bio *bio);
802 extern void blk_rq_init(struct request_queue *q, struct request *rq);
803 extern void blk_put_request(struct request *);
804 extern void __blk_put_request(struct request_queue *, struct request *);
805 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
806 extern struct request *blk_make_request(struct request_queue *, struct bio *,
808 extern void blk_rq_set_block_pc(struct request *);
809 extern void blk_requeue_request(struct request_queue *, struct request *);
810 extern void blk_add_request_payload(struct request *rq, struct page *page,
811 int offset, unsigned int len);
812 extern int blk_lld_busy(struct request_queue *q);
813 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
814 struct bio_set *bs, gfp_t gfp_mask,
815 int (*bio_ctr)(struct bio *, struct bio *, void *),
817 extern void blk_rq_unprep_clone(struct request *rq);
818 extern int blk_insert_cloned_request(struct request_queue *q,
820 extern void blk_delay_queue(struct request_queue *, unsigned long);
821 extern void blk_queue_split(struct request_queue *, struct bio **,
823 extern void blk_recount_segments(struct request_queue *, struct bio *);
824 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
825 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
826 unsigned int, void __user *);
827 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
828 unsigned int, void __user *);
829 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
830 struct scsi_ioctl_command __user *);
832 extern int blk_queue_enter(struct request_queue *q, bool nowait);
833 extern void blk_queue_exit(struct request_queue *q);
834 extern void blk_start_queue(struct request_queue *q);
835 extern void blk_start_queue_async(struct request_queue *q);
836 extern void blk_stop_queue(struct request_queue *q);
837 extern void blk_sync_queue(struct request_queue *q);
838 extern void __blk_stop_queue(struct request_queue *q);
839 extern void __blk_run_queue(struct request_queue *q);
840 extern void __blk_run_queue_uncond(struct request_queue *q);
841 extern void blk_run_queue(struct request_queue *);
842 extern void blk_run_queue_async(struct request_queue *q);
843 extern int blk_rq_map_user(struct request_queue *, struct request *,
844 struct rq_map_data *, void __user *, unsigned long,
846 extern int blk_rq_unmap_user(struct bio *);
847 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
848 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
849 struct rq_map_data *, const struct iov_iter *,
851 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
852 struct request *, int);
853 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
854 struct request *, int, rq_end_io_fn *);
856 bool blk_poll(struct request_queue *q, blk_qc_t cookie);
858 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
860 return bdev->bd_disk->queue; /* this is never NULL */
864 * blk_rq_pos() : the current sector
865 * blk_rq_bytes() : bytes left in the entire request
866 * blk_rq_cur_bytes() : bytes left in the current segment
867 * blk_rq_err_bytes() : bytes left till the next error boundary
868 * blk_rq_sectors() : sectors left in the entire request
869 * blk_rq_cur_sectors() : sectors left in the current segment
871 static inline sector_t blk_rq_pos(const struct request *rq)
876 static inline unsigned int blk_rq_bytes(const struct request *rq)
878 return rq->__data_len;
881 static inline int blk_rq_cur_bytes(const struct request *rq)
883 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
886 extern unsigned int blk_rq_err_bytes(const struct request *rq);
888 static inline unsigned int blk_rq_sectors(const struct request *rq)
890 return blk_rq_bytes(rq) >> 9;
893 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
895 return blk_rq_cur_bytes(rq) >> 9;
898 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
901 if (unlikely(op == REQ_OP_DISCARD))
902 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
904 if (unlikely(op == REQ_OP_WRITE_SAME))
905 return q->limits.max_write_same_sectors;
907 return q->limits.max_sectors;
911 * Return maximum size of a request at given offset. Only valid for
912 * file system requests.
914 static inline unsigned int blk_max_size_offset(struct request_queue *q,
917 if (!q->limits.chunk_sectors)
918 return q->limits.max_sectors;
920 return q->limits.chunk_sectors -
921 (offset & (q->limits.chunk_sectors - 1));
924 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
926 struct request_queue *q = rq->q;
928 if (unlikely(rq->cmd_type != REQ_TYPE_FS))
929 return q->limits.max_hw_sectors;
931 if (!q->limits.chunk_sectors || (req_op(rq) == REQ_OP_DISCARD))
932 return blk_queue_get_max_sectors(q, req_op(rq));
934 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
935 blk_queue_get_max_sectors(q, req_op(rq)));
938 static inline unsigned int blk_rq_count_bios(struct request *rq)
940 unsigned int nr_bios = 0;
943 __rq_for_each_bio(bio, rq)
950 * Request issue related functions.
952 extern struct request *blk_peek_request(struct request_queue *q);
953 extern void blk_start_request(struct request *rq);
954 extern struct request *blk_fetch_request(struct request_queue *q);
957 * Request completion related functions.
959 * blk_update_request() completes given number of bytes and updates
960 * the request without completing it.
962 * blk_end_request() and friends. __blk_end_request() must be called
963 * with the request queue spinlock acquired.
965 * Several drivers define their own end_request and call
966 * blk_end_request() for parts of the original function.
967 * This prevents code duplication in drivers.
969 extern bool blk_update_request(struct request *rq, int error,
970 unsigned int nr_bytes);
971 extern void blk_finish_request(struct request *rq, int error);
972 extern bool blk_end_request(struct request *rq, int error,
973 unsigned int nr_bytes);
974 extern void blk_end_request_all(struct request *rq, int error);
975 extern bool blk_end_request_cur(struct request *rq, int error);
976 extern bool blk_end_request_err(struct request *rq, int error);
977 extern bool __blk_end_request(struct request *rq, int error,
978 unsigned int nr_bytes);
979 extern void __blk_end_request_all(struct request *rq, int error);
980 extern bool __blk_end_request_cur(struct request *rq, int error);
981 extern bool __blk_end_request_err(struct request *rq, int error);
983 extern void blk_complete_request(struct request *);
984 extern void __blk_complete_request(struct request *);
985 extern void blk_abort_request(struct request *);
986 extern void blk_unprep_request(struct request *);
989 * Access functions for manipulating queue properties
991 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
992 spinlock_t *lock, int node_id);
993 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
994 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
995 request_fn_proc *, spinlock_t *);
996 extern void blk_cleanup_queue(struct request_queue *);
997 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
998 extern void blk_queue_bounce_limit(struct request_queue *, u64);
999 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1000 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1001 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1002 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1003 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1004 unsigned int max_discard_sectors);
1005 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1006 unsigned int max_write_same_sectors);
1007 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
1008 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1009 extern void blk_queue_alignment_offset(struct request_queue *q,
1010 unsigned int alignment);
1011 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1012 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1013 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1014 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1015 extern void blk_set_default_limits(struct queue_limits *lim);
1016 extern void blk_set_stacking_limits(struct queue_limits *lim);
1017 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1019 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1021 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1023 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1024 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1025 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1026 extern int blk_queue_dma_drain(struct request_queue *q,
1027 dma_drain_needed_fn *dma_drain_needed,
1028 void *buf, unsigned int size);
1029 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1030 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1031 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1032 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1033 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1034 extern void blk_queue_dma_alignment(struct request_queue *, int);
1035 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1036 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1037 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1038 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1039 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1040 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1041 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1043 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1044 extern void blk_dump_rq_flags(struct request *, char *);
1045 extern long nr_blockdev_pages(void);
1047 bool __must_check blk_get_queue(struct request_queue *);
1048 struct request_queue *blk_alloc_queue(gfp_t);
1049 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1050 extern void blk_put_queue(struct request_queue *);
1051 extern void blk_set_queue_dying(struct request_queue *);
1054 * block layer runtime pm functions
1057 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1058 extern int blk_pre_runtime_suspend(struct request_queue *q);
1059 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1060 extern void blk_pre_runtime_resume(struct request_queue *q);
1061 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1062 extern void blk_set_runtime_active(struct request_queue *q);
1064 static inline void blk_pm_runtime_init(struct request_queue *q,
1065 struct device *dev) {}
1066 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1070 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1071 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1072 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1073 extern inline void blk_set_runtime_active(struct request_queue *q) {}
1077 * blk_plug permits building a queue of related requests by holding the I/O
1078 * fragments for a short period. This allows merging of sequential requests
1079 * into single larger request. As the requests are moved from a per-task list to
1080 * the device's request_queue in a batch, this results in improved scalability
1081 * as the lock contention for request_queue lock is reduced.
1083 * It is ok not to disable preemption when adding the request to the plug list
1084 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1085 * the plug list when the task sleeps by itself. For details, please see
1086 * schedule() where blk_schedule_flush_plug() is called.
1089 struct list_head list; /* requests */
1090 struct list_head mq_list; /* blk-mq requests */
1091 struct list_head cb_list; /* md requires an unplug callback */
1093 #define BLK_MAX_REQUEST_COUNT 16
1096 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1097 struct blk_plug_cb {
1098 struct list_head list;
1099 blk_plug_cb_fn callback;
1102 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1103 void *data, int size);
1104 extern void blk_start_plug(struct blk_plug *);
1105 extern void blk_finish_plug(struct blk_plug *);
1106 extern void blk_flush_plug_list(struct blk_plug *, bool);
1108 static inline void blk_flush_plug(struct task_struct *tsk)
1110 struct blk_plug *plug = tsk->plug;
1113 blk_flush_plug_list(plug, false);
1116 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1118 struct blk_plug *plug = tsk->plug;
1121 blk_flush_plug_list(plug, true);
1124 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1126 struct blk_plug *plug = tsk->plug;
1129 (!list_empty(&plug->list) ||
1130 !list_empty(&plug->mq_list) ||
1131 !list_empty(&plug->cb_list));
1137 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1138 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1139 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1140 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1141 extern void blk_queue_free_tags(struct request_queue *);
1142 extern int blk_queue_resize_tags(struct request_queue *, int);
1143 extern void blk_queue_invalidate_tags(struct request_queue *);
1144 extern struct blk_queue_tag *blk_init_tags(int, int);
1145 extern void blk_free_tags(struct blk_queue_tag *);
1147 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1150 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1152 return bqt->tag_index[tag];
1155 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1157 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1158 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1159 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1160 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1161 sector_t nr_sects, gfp_t gfp_mask, int op_flags,
1163 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1164 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1165 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1166 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1167 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1168 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1170 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1171 nr_blocks << (sb->s_blocksize_bits - 9),
1174 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1175 sector_t nr_blocks, gfp_t gfp_mask)
1177 return blkdev_issue_zeroout(sb->s_bdev,
1178 block << (sb->s_blocksize_bits - 9),
1179 nr_blocks << (sb->s_blocksize_bits - 9),
1183 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1185 enum blk_default_limits {
1186 BLK_MAX_SEGMENTS = 128,
1187 BLK_SAFE_MAX_SECTORS = 255,
1188 BLK_DEF_MAX_SECTORS = 2560,
1189 BLK_MAX_SEGMENT_SIZE = 65536,
1190 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1193 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1195 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1197 return q->limits.bounce_pfn;
1200 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1202 return q->limits.seg_boundary_mask;
1205 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1207 return q->limits.virt_boundary_mask;
1210 static inline unsigned int queue_max_sectors(struct request_queue *q)
1212 return q->limits.max_sectors;
1215 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1217 return q->limits.max_hw_sectors;
1220 static inline unsigned short queue_max_segments(struct request_queue *q)
1222 return q->limits.max_segments;
1225 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1227 return q->limits.max_segment_size;
1230 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1234 if (q && q->limits.logical_block_size)
1235 retval = q->limits.logical_block_size;
1240 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1242 return queue_logical_block_size(bdev_get_queue(bdev));
1245 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1247 return q->limits.physical_block_size;
1250 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1252 return queue_physical_block_size(bdev_get_queue(bdev));
1255 static inline unsigned int queue_io_min(struct request_queue *q)
1257 return q->limits.io_min;
1260 static inline int bdev_io_min(struct block_device *bdev)
1262 return queue_io_min(bdev_get_queue(bdev));
1265 static inline unsigned int queue_io_opt(struct request_queue *q)
1267 return q->limits.io_opt;
1270 static inline int bdev_io_opt(struct block_device *bdev)
1272 return queue_io_opt(bdev_get_queue(bdev));
1275 static inline int queue_alignment_offset(struct request_queue *q)
1277 if (q->limits.misaligned)
1280 return q->limits.alignment_offset;
1283 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1285 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1286 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1288 return (granularity + lim->alignment_offset - alignment) % granularity;
1291 static inline int bdev_alignment_offset(struct block_device *bdev)
1293 struct request_queue *q = bdev_get_queue(bdev);
1295 if (q->limits.misaligned)
1298 if (bdev != bdev->bd_contains)
1299 return bdev->bd_part->alignment_offset;
1301 return q->limits.alignment_offset;
1304 static inline int queue_discard_alignment(struct request_queue *q)
1306 if (q->limits.discard_misaligned)
1309 return q->limits.discard_alignment;
1312 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1314 unsigned int alignment, granularity, offset;
1316 if (!lim->max_discard_sectors)
1319 /* Why are these in bytes, not sectors? */
1320 alignment = lim->discard_alignment >> 9;
1321 granularity = lim->discard_granularity >> 9;
1325 /* Offset of the partition start in 'granularity' sectors */
1326 offset = sector_div(sector, granularity);
1328 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1329 offset = (granularity + alignment - offset) % granularity;
1331 /* Turn it back into bytes, gaah */
1335 static inline int bdev_discard_alignment(struct block_device *bdev)
1337 struct request_queue *q = bdev_get_queue(bdev);
1339 if (bdev != bdev->bd_contains)
1340 return bdev->bd_part->discard_alignment;
1342 return q->limits.discard_alignment;
1345 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1347 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1353 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1355 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1358 static inline unsigned int bdev_write_same(struct block_device *bdev)
1360 struct request_queue *q = bdev_get_queue(bdev);
1363 return q->limits.max_write_same_sectors;
1368 static inline int queue_dma_alignment(struct request_queue *q)
1370 return q ? q->dma_alignment : 511;
1373 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1376 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1377 return !(addr & alignment) && !(len & alignment);
1380 /* assumes size > 256 */
1381 static inline unsigned int blksize_bits(unsigned int size)
1383 unsigned int bits = 8;
1387 } while (size > 256);
1391 static inline unsigned int block_size(struct block_device *bdev)
1393 return bdev->bd_block_size;
1396 static inline bool queue_flush_queueable(struct request_queue *q)
1398 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags);
1401 typedef struct {struct page *v;} Sector;
1403 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1405 static inline void put_dev_sector(Sector p)
1410 static inline bool __bvec_gap_to_prev(struct request_queue *q,
1411 struct bio_vec *bprv, unsigned int offset)
1414 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1418 * Check if adding a bio_vec after bprv with offset would create a gap in
1419 * the SG list. Most drivers don't care about this, but some do.
1421 static inline bool bvec_gap_to_prev(struct request_queue *q,
1422 struct bio_vec *bprv, unsigned int offset)
1424 if (!queue_virt_boundary(q))
1426 return __bvec_gap_to_prev(q, bprv, offset);
1429 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1432 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1433 struct bio_vec pb, nb;
1435 bio_get_last_bvec(prev, &pb);
1436 bio_get_first_bvec(next, &nb);
1438 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1444 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1446 return bio_will_gap(req->q, req->biotail, bio);
1449 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1451 return bio_will_gap(req->q, bio, req->bio);
1455 int kblockd_schedule_work(struct work_struct *work);
1456 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1457 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1459 #ifdef CONFIG_BLK_CGROUP
1461 * This should not be using sched_clock(). A real patch is in progress
1462 * to fix this up, until that is in place we need to disable preemption
1463 * around sched_clock() in this function and set_io_start_time_ns().
1465 static inline void set_start_time_ns(struct request *req)
1468 req->start_time_ns = sched_clock();
1472 static inline void set_io_start_time_ns(struct request *req)
1475 req->io_start_time_ns = sched_clock();
1479 static inline uint64_t rq_start_time_ns(struct request *req)
1481 return req->start_time_ns;
1484 static inline uint64_t rq_io_start_time_ns(struct request *req)
1486 return req->io_start_time_ns;
1489 static inline void set_start_time_ns(struct request *req) {}
1490 static inline void set_io_start_time_ns(struct request *req) {}
1491 static inline uint64_t rq_start_time_ns(struct request *req)
1495 static inline uint64_t rq_io_start_time_ns(struct request *req)
1501 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1502 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1503 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1504 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1506 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1508 enum blk_integrity_flags {
1509 BLK_INTEGRITY_VERIFY = 1 << 0,
1510 BLK_INTEGRITY_GENERATE = 1 << 1,
1511 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1512 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1515 struct blk_integrity_iter {
1519 unsigned int data_size;
1520 unsigned short interval;
1521 const char *disk_name;
1524 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1526 struct blk_integrity_profile {
1527 integrity_processing_fn *generate_fn;
1528 integrity_processing_fn *verify_fn;
1532 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1533 extern void blk_integrity_unregister(struct gendisk *);
1534 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1535 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1536 struct scatterlist *);
1537 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1538 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1540 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1543 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1545 struct blk_integrity *bi = &disk->queue->integrity;
1554 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1556 return blk_get_integrity(bdev->bd_disk);
1559 static inline bool blk_integrity_rq(struct request *rq)
1561 return rq->cmd_flags & REQ_INTEGRITY;
1564 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1567 q->limits.max_integrity_segments = segs;
1570 static inline unsigned short
1571 queue_max_integrity_segments(struct request_queue *q)
1573 return q->limits.max_integrity_segments;
1576 static inline bool integrity_req_gap_back_merge(struct request *req,
1579 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1580 struct bio_integrity_payload *bip_next = bio_integrity(next);
1582 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1583 bip_next->bip_vec[0].bv_offset);
1586 static inline bool integrity_req_gap_front_merge(struct request *req,
1589 struct bio_integrity_payload *bip = bio_integrity(bio);
1590 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1592 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1593 bip_next->bip_vec[0].bv_offset);
1596 #else /* CONFIG_BLK_DEV_INTEGRITY */
1599 struct block_device;
1601 struct blk_integrity;
1603 static inline int blk_integrity_rq(struct request *rq)
1607 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1612 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1614 struct scatterlist *s)
1618 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1622 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1626 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1630 static inline void blk_integrity_register(struct gendisk *d,
1631 struct blk_integrity *b)
1634 static inline void blk_integrity_unregister(struct gendisk *d)
1637 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1641 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1645 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1651 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1658 static inline bool integrity_req_gap_back_merge(struct request *req,
1663 static inline bool integrity_req_gap_front_merge(struct request *req,
1669 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1672 * struct blk_dax_ctl - control and output parameters for ->direct_access
1673 * @sector: (input) offset relative to a block_device
1674 * @addr: (output) kernel virtual address for @sector populated by driver
1675 * @pfn: (output) page frame number for @addr populated by driver
1676 * @size: (input) number of bytes requested
1678 struct blk_dax_ctl {
1685 struct block_device_operations {
1686 int (*open) (struct block_device *, fmode_t);
1687 void (*release) (struct gendisk *, fmode_t);
1688 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1689 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1690 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1691 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
1693 unsigned int (*check_events) (struct gendisk *disk,
1694 unsigned int clearing);
1695 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1696 int (*media_changed) (struct gendisk *);
1697 void (*unlock_native_capacity) (struct gendisk *);
1698 int (*revalidate_disk) (struct gendisk *);
1699 int (*getgeo)(struct block_device *, struct hd_geometry *);
1700 /* this callback is with swap_lock and sometimes page table lock held */
1701 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1702 struct module *owner;
1703 const struct pr_ops *pr_ops;
1706 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1708 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1709 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1710 struct writeback_control *);
1711 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *);
1712 extern int bdev_dax_supported(struct super_block *, int);
1713 extern bool bdev_dax_capable(struct block_device *);
1714 #else /* CONFIG_BLOCK */
1716 struct block_device;
1719 * stubs for when the block layer is configured out
1721 #define buffer_heads_over_limit 0
1723 static inline long nr_blockdev_pages(void)
1731 static inline void blk_start_plug(struct blk_plug *plug)
1735 static inline void blk_finish_plug(struct blk_plug *plug)
1739 static inline void blk_flush_plug(struct task_struct *task)
1743 static inline void blk_schedule_flush_plug(struct task_struct *task)
1748 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1753 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1754 sector_t *error_sector)
1759 #endif /* CONFIG_BLOCK */