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;
102 unsigned long atomic_flags;
104 /* the following two fields are internal, NEVER access directly */
105 unsigned int __data_len; /* total data len */
106 sector_t __sector; /* sector cursor */
112 * The hash is used inside the scheduler, and killed once the
113 * request reaches the dispatch list. The ipi_list is only used
114 * to queue the request for softirq completion, which is long
115 * after the request has been unhashed (and even removed from
116 * the dispatch list).
119 struct hlist_node hash; /* merge hash */
120 struct list_head ipi_list;
124 * The rb_node is only used inside the io scheduler, requests
125 * are pruned when moved to the dispatch queue. So let the
126 * completion_data share space with the rb_node.
129 struct rb_node rb_node; /* sort/lookup */
130 void *completion_data;
134 * Three pointers are available for the IO schedulers, if they need
135 * more they have to dynamically allocate it. Flush requests are
136 * never put on the IO scheduler. So let the flush fields share
137 * space with the elevator data.
147 struct list_head list;
148 rq_end_io_fn *saved_end_io;
152 struct gendisk *rq_disk;
153 struct hd_struct *part;
154 unsigned long start_time;
155 #ifdef CONFIG_BLK_CGROUP
156 struct request_list *rl; /* rl this rq is alloced from */
157 unsigned long long start_time_ns;
158 unsigned long long io_start_time_ns; /* when passed to hardware */
160 /* Number of scatter-gather DMA addr+len pairs after
161 * physical address coalescing is performed.
163 unsigned short nr_phys_segments;
164 #if defined(CONFIG_BLK_DEV_INTEGRITY)
165 unsigned short nr_integrity_segments;
168 unsigned short ioprio;
170 void *special; /* opaque pointer available for LLD use */
176 * when request is used as a packet command carrier
178 unsigned char __cmd[BLK_MAX_CDB];
180 unsigned short cmd_len;
182 unsigned int extra_len; /* length of alignment and padding */
183 unsigned int sense_len;
184 unsigned int resid_len; /* residual count */
187 unsigned long deadline;
188 struct list_head timeout_list;
189 unsigned int timeout;
193 * completion callback.
195 rq_end_io_fn *end_io;
199 struct request *next_rq;
202 #define REQ_OP_SHIFT (8 * sizeof(u64) - REQ_OP_BITS)
203 #define req_op(req) ((req)->cmd_flags >> REQ_OP_SHIFT)
205 #define req_set_op(req, op) do { \
206 WARN_ON(op >= (1 << REQ_OP_BITS)); \
207 (req)->cmd_flags &= ((1ULL << REQ_OP_SHIFT) - 1); \
208 (req)->cmd_flags |= ((u64) (op) << REQ_OP_SHIFT); \
211 #define req_set_op_attrs(req, op, flags) do { \
212 req_set_op(req, op); \
213 (req)->cmd_flags |= flags; \
216 static inline unsigned short req_get_ioprio(struct request *req)
221 #include <linux/elevator.h>
223 struct blk_queue_ctx;
225 typedef void (request_fn_proc) (struct request_queue *q);
226 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
227 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
228 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
231 typedef void (softirq_done_fn)(struct request *);
232 typedef int (dma_drain_needed_fn)(struct request *);
233 typedef int (lld_busy_fn) (struct request_queue *q);
234 typedef int (bsg_job_fn) (struct bsg_job *);
236 enum blk_eh_timer_return {
242 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
244 enum blk_queue_state {
249 struct blk_queue_tag {
250 struct request **tag_index; /* map of busy tags */
251 unsigned long *tag_map; /* bit map of free/busy tags */
252 int busy; /* current depth */
253 int max_depth; /* what we will send to device */
254 int real_max_depth; /* what the array can hold */
255 atomic_t refcnt; /* map can be shared */
256 int alloc_policy; /* tag allocation policy */
257 int next_tag; /* next tag */
259 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
260 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
262 #define BLK_SCSI_MAX_CMDS (256)
263 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
265 struct queue_limits {
266 unsigned long bounce_pfn;
267 unsigned long seg_boundary_mask;
268 unsigned long virt_boundary_mask;
270 unsigned int max_hw_sectors;
271 unsigned int max_dev_sectors;
272 unsigned int chunk_sectors;
273 unsigned int max_sectors;
274 unsigned int max_segment_size;
275 unsigned int physical_block_size;
276 unsigned int alignment_offset;
279 unsigned int max_discard_sectors;
280 unsigned int max_hw_discard_sectors;
281 unsigned int max_write_same_sectors;
282 unsigned int discard_granularity;
283 unsigned int discard_alignment;
285 unsigned short logical_block_size;
286 unsigned short max_segments;
287 unsigned short max_integrity_segments;
289 unsigned char misaligned;
290 unsigned char discard_misaligned;
291 unsigned char cluster;
292 unsigned char discard_zeroes_data;
293 unsigned char raid_partial_stripes_expensive;
296 struct request_queue {
298 * Together with queue_head for cacheline sharing
300 struct list_head queue_head;
301 struct request *last_merge;
302 struct elevator_queue *elevator;
303 int nr_rqs[2]; /* # allocated [a]sync rqs */
304 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
307 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
308 * is used, root blkg allocates from @q->root_rl and all other
309 * blkgs from their own blkg->rl. Which one to use should be
310 * determined using bio_request_list().
312 struct request_list root_rl;
314 request_fn_proc *request_fn;
315 make_request_fn *make_request_fn;
316 prep_rq_fn *prep_rq_fn;
317 unprep_rq_fn *unprep_rq_fn;
318 softirq_done_fn *softirq_done_fn;
319 rq_timed_out_fn *rq_timed_out_fn;
320 dma_drain_needed_fn *dma_drain_needed;
321 lld_busy_fn *lld_busy_fn;
323 struct blk_mq_ops *mq_ops;
325 unsigned int *mq_map;
328 struct blk_mq_ctx __percpu *queue_ctx;
329 unsigned int nr_queues;
331 /* hw dispatch queues */
332 struct blk_mq_hw_ctx **queue_hw_ctx;
333 unsigned int nr_hw_queues;
336 * Dispatch queue sorting
339 struct request *boundary_rq;
342 * Delayed queue handling
344 struct delayed_work delay_work;
346 struct backing_dev_info backing_dev_info;
349 * The queue owner gets to use this for whatever they like.
350 * ll_rw_blk doesn't touch it.
355 * various queue flags, see QUEUE_* below
357 unsigned long queue_flags;
360 * ida allocated id for this queue. Used to index queues from
366 * queue needs bounce pages for pages above this limit
371 * protects queue structures from reentrancy. ->__queue_lock should
372 * _never_ be used directly, it is queue private. always use
375 spinlock_t __queue_lock;
376 spinlock_t *queue_lock;
386 struct kobject mq_kobj;
388 #ifdef CONFIG_BLK_DEV_INTEGRITY
389 struct blk_integrity integrity;
390 #endif /* CONFIG_BLK_DEV_INTEGRITY */
395 unsigned int nr_pending;
401 unsigned long nr_requests; /* Max # of requests */
402 unsigned int nr_congestion_on;
403 unsigned int nr_congestion_off;
404 unsigned int nr_batching;
406 unsigned int dma_drain_size;
407 void *dma_drain_buffer;
408 unsigned int dma_pad_mask;
409 unsigned int dma_alignment;
411 struct blk_queue_tag *queue_tags;
412 struct list_head tag_busy_list;
414 unsigned int nr_sorted;
415 unsigned int in_flight[2];
417 * Number of active block driver functions for which blk_drain_queue()
418 * must wait. Must be incremented around functions that unlock the
419 * queue_lock internally, e.g. scsi_request_fn().
421 unsigned int request_fn_active;
423 unsigned int rq_timeout;
424 struct timer_list timeout;
425 struct work_struct timeout_work;
426 struct list_head timeout_list;
428 struct list_head icq_list;
429 #ifdef CONFIG_BLK_CGROUP
430 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
431 struct blkcg_gq *root_blkg;
432 struct list_head blkg_list;
435 struct queue_limits limits;
440 unsigned int sg_timeout;
441 unsigned int sg_reserved_size;
443 #ifdef CONFIG_BLK_DEV_IO_TRACE
444 struct blk_trace *blk_trace;
447 * for flush operations
449 struct blk_flush_queue *fq;
451 struct list_head requeue_list;
452 spinlock_t requeue_lock;
453 struct work_struct requeue_work;
455 struct mutex sysfs_lock;
458 atomic_t mq_freeze_depth;
460 #if defined(CONFIG_BLK_DEV_BSG)
461 bsg_job_fn *bsg_job_fn;
463 struct bsg_class_device bsg_dev;
466 #ifdef CONFIG_BLK_DEV_THROTTLING
468 struct throtl_data *td;
470 struct rcu_head rcu_head;
471 wait_queue_head_t mq_freeze_wq;
472 struct percpu_ref q_usage_counter;
473 struct list_head all_q_node;
475 struct blk_mq_tag_set *tag_set;
476 struct list_head tag_set_list;
477 struct bio_set *bio_split;
479 bool mq_sysfs_init_done;
482 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
483 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
484 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
485 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
486 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
487 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
488 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
489 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
490 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
491 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
492 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
493 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
494 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
495 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
496 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
497 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
498 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
499 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
500 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
501 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
502 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
503 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
504 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
505 #define QUEUE_FLAG_WC 23 /* Write back caching */
506 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
507 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
509 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
510 (1 << QUEUE_FLAG_STACKABLE) | \
511 (1 << QUEUE_FLAG_SAME_COMP) | \
512 (1 << QUEUE_FLAG_ADD_RANDOM))
514 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
515 (1 << QUEUE_FLAG_STACKABLE) | \
516 (1 << QUEUE_FLAG_SAME_COMP) | \
517 (1 << QUEUE_FLAG_POLL))
519 static inline void queue_lockdep_assert_held(struct request_queue *q)
522 lockdep_assert_held(q->queue_lock);
525 static inline void queue_flag_set_unlocked(unsigned int flag,
526 struct request_queue *q)
528 __set_bit(flag, &q->queue_flags);
531 static inline int queue_flag_test_and_clear(unsigned int flag,
532 struct request_queue *q)
534 queue_lockdep_assert_held(q);
536 if (test_bit(flag, &q->queue_flags)) {
537 __clear_bit(flag, &q->queue_flags);
544 static inline int queue_flag_test_and_set(unsigned int flag,
545 struct request_queue *q)
547 queue_lockdep_assert_held(q);
549 if (!test_bit(flag, &q->queue_flags)) {
550 __set_bit(flag, &q->queue_flags);
557 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
559 queue_lockdep_assert_held(q);
560 __set_bit(flag, &q->queue_flags);
563 static inline void queue_flag_clear_unlocked(unsigned int flag,
564 struct request_queue *q)
566 __clear_bit(flag, &q->queue_flags);
569 static inline int queue_in_flight(struct request_queue *q)
571 return q->in_flight[0] + q->in_flight[1];
574 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
576 queue_lockdep_assert_held(q);
577 __clear_bit(flag, &q->queue_flags);
580 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
581 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
582 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
583 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
584 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
585 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
586 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
587 #define blk_queue_noxmerges(q) \
588 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
589 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
590 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
591 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
592 #define blk_queue_stackable(q) \
593 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
594 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
595 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
596 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
598 #define blk_noretry_request(rq) \
599 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
600 REQ_FAILFAST_DRIVER))
602 #define blk_account_rq(rq) \
603 (((rq)->cmd_flags & REQ_STARTED) && \
604 ((rq)->cmd_type == REQ_TYPE_FS))
606 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
607 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
608 /* rq->queuelist of dequeued request must be list_empty() */
609 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
611 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
613 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
616 * Driver can handle struct request, if it either has an old style
617 * request_fn defined, or is blk-mq based.
619 static inline bool queue_is_rq_based(struct request_queue *q)
621 return q->request_fn || q->mq_ops;
624 static inline unsigned int blk_queue_cluster(struct request_queue *q)
626 return q->limits.cluster;
630 * We regard a request as sync, if either a read or a sync write
632 static inline bool rw_is_sync(int op, unsigned int rw_flags)
634 return op == REQ_OP_READ || (rw_flags & REQ_SYNC);
637 static inline bool rq_is_sync(struct request *rq)
639 return rw_is_sync(req_op(rq), rq->cmd_flags);
642 static inline bool blk_rl_full(struct request_list *rl, bool sync)
644 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
646 return rl->flags & flag;
649 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
651 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
656 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
658 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
663 static inline bool rq_mergeable(struct request *rq)
665 if (rq->cmd_type != REQ_TYPE_FS)
668 if (req_op(rq) == REQ_OP_FLUSH)
671 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
677 static inline bool blk_check_merge_flags(unsigned int flags1, unsigned int op1,
678 unsigned int flags2, unsigned int op2)
680 if ((op1 == REQ_OP_DISCARD) != (op2 == REQ_OP_DISCARD))
683 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
686 if ((op1 == REQ_OP_WRITE_SAME) != (op2 == REQ_OP_WRITE_SAME))
692 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
694 if (bio_data(a) == bio_data(b))
701 * q->prep_rq_fn return values
704 BLKPREP_OK, /* serve it */
705 BLKPREP_KILL, /* fatal error, kill, return -EIO */
706 BLKPREP_DEFER, /* leave on queue */
707 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */
710 extern unsigned long blk_max_low_pfn, blk_max_pfn;
713 * standard bounce addresses:
715 * BLK_BOUNCE_HIGH : bounce all highmem pages
716 * BLK_BOUNCE_ANY : don't bounce anything
717 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
720 #if BITS_PER_LONG == 32
721 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
723 #define BLK_BOUNCE_HIGH -1ULL
725 #define BLK_BOUNCE_ANY (-1ULL)
726 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
729 * default timeout for SG_IO if none specified
731 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
732 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
735 extern int init_emergency_isa_pool(void);
736 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
738 static inline int init_emergency_isa_pool(void)
742 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
745 #endif /* CONFIG_MMU */
751 unsigned long offset;
756 struct req_iterator {
757 struct bvec_iter iter;
761 /* This should not be used directly - use rq_for_each_segment */
762 #define for_each_bio(_bio) \
763 for (; _bio; _bio = _bio->bi_next)
764 #define __rq_for_each_bio(_bio, rq) \
766 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
768 #define rq_for_each_segment(bvl, _rq, _iter) \
769 __rq_for_each_bio(_iter.bio, _rq) \
770 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
772 #define rq_iter_last(bvec, _iter) \
773 (_iter.bio->bi_next == NULL && \
774 bio_iter_last(bvec, _iter.iter))
776 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
777 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
779 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
780 extern void rq_flush_dcache_pages(struct request *rq);
782 static inline void rq_flush_dcache_pages(struct request *rq)
788 #define vfs_msg(sb, level, fmt, ...) \
789 __vfs_msg(sb, level, fmt, ##__VA_ARGS__)
791 #define vfs_msg(sb, level, fmt, ...) \
793 no_printk(fmt, ##__VA_ARGS__); \
794 __vfs_msg(sb, "", " "); \
798 extern int blk_register_queue(struct gendisk *disk);
799 extern void blk_unregister_queue(struct gendisk *disk);
800 extern blk_qc_t generic_make_request(struct bio *bio);
801 extern void blk_rq_init(struct request_queue *q, struct request *rq);
802 extern void blk_put_request(struct request *);
803 extern void __blk_put_request(struct request_queue *, struct request *);
804 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
805 extern struct request *blk_make_request(struct request_queue *, struct bio *,
807 extern void blk_rq_set_block_pc(struct request *);
808 extern void blk_requeue_request(struct request_queue *, struct request *);
809 extern void blk_add_request_payload(struct request *rq, struct page *page,
810 int offset, unsigned int len);
811 extern int blk_lld_busy(struct request_queue *q);
812 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
813 struct bio_set *bs, gfp_t gfp_mask,
814 int (*bio_ctr)(struct bio *, struct bio *, void *),
816 extern void blk_rq_unprep_clone(struct request *rq);
817 extern int blk_insert_cloned_request(struct request_queue *q,
819 extern void blk_delay_queue(struct request_queue *, unsigned long);
820 extern void blk_queue_split(struct request_queue *, struct bio **,
822 extern void blk_recount_segments(struct request_queue *, struct bio *);
823 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
824 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
825 unsigned int, void __user *);
826 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
827 unsigned int, void __user *);
828 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
829 struct scsi_ioctl_command __user *);
831 extern int blk_queue_enter(struct request_queue *q, bool nowait);
832 extern void blk_queue_exit(struct request_queue *q);
833 extern void blk_start_queue(struct request_queue *q);
834 extern void blk_start_queue_async(struct request_queue *q);
835 extern void blk_stop_queue(struct request_queue *q);
836 extern void blk_sync_queue(struct request_queue *q);
837 extern void __blk_stop_queue(struct request_queue *q);
838 extern void __blk_run_queue(struct request_queue *q);
839 extern void __blk_run_queue_uncond(struct request_queue *q);
840 extern void blk_run_queue(struct request_queue *);
841 extern void blk_run_queue_async(struct request_queue *q);
842 extern int blk_rq_map_user(struct request_queue *, struct request *,
843 struct rq_map_data *, void __user *, unsigned long,
845 extern int blk_rq_unmap_user(struct bio *);
846 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
847 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
848 struct rq_map_data *, const struct iov_iter *,
850 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
851 struct request *, int);
852 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
853 struct request *, int, rq_end_io_fn *);
855 bool blk_poll(struct request_queue *q, blk_qc_t cookie);
857 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
859 return bdev->bd_disk->queue; /* this is never NULL */
863 * blk_rq_pos() : the current sector
864 * blk_rq_bytes() : bytes left in the entire request
865 * blk_rq_cur_bytes() : bytes left in the current segment
866 * blk_rq_err_bytes() : bytes left till the next error boundary
867 * blk_rq_sectors() : sectors left in the entire request
868 * blk_rq_cur_sectors() : sectors left in the current segment
870 static inline sector_t blk_rq_pos(const struct request *rq)
875 static inline unsigned int blk_rq_bytes(const struct request *rq)
877 return rq->__data_len;
880 static inline int blk_rq_cur_bytes(const struct request *rq)
882 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
885 extern unsigned int blk_rq_err_bytes(const struct request *rq);
887 static inline unsigned int blk_rq_sectors(const struct request *rq)
889 return blk_rq_bytes(rq) >> 9;
892 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
894 return blk_rq_cur_bytes(rq) >> 9;
897 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
900 if (unlikely(op == REQ_OP_DISCARD))
901 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
903 if (unlikely(op == REQ_OP_WRITE_SAME))
904 return q->limits.max_write_same_sectors;
906 return q->limits.max_sectors;
910 * Return maximum size of a request at given offset. Only valid for
911 * file system requests.
913 static inline unsigned int blk_max_size_offset(struct request_queue *q,
916 if (!q->limits.chunk_sectors)
917 return q->limits.max_sectors;
919 return q->limits.chunk_sectors -
920 (offset & (q->limits.chunk_sectors - 1));
923 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
925 struct request_queue *q = rq->q;
927 if (unlikely(rq->cmd_type != REQ_TYPE_FS))
928 return q->limits.max_hw_sectors;
930 if (!q->limits.chunk_sectors || (req_op(rq) == REQ_OP_DISCARD))
931 return blk_queue_get_max_sectors(q, req_op(rq));
933 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
934 blk_queue_get_max_sectors(q, req_op(rq)));
937 static inline unsigned int blk_rq_count_bios(struct request *rq)
939 unsigned int nr_bios = 0;
942 __rq_for_each_bio(bio, rq)
949 * Request issue related functions.
951 extern struct request *blk_peek_request(struct request_queue *q);
952 extern void blk_start_request(struct request *rq);
953 extern struct request *blk_fetch_request(struct request_queue *q);
956 * Request completion related functions.
958 * blk_update_request() completes given number of bytes and updates
959 * the request without completing it.
961 * blk_end_request() and friends. __blk_end_request() must be called
962 * with the request queue spinlock acquired.
964 * Several drivers define their own end_request and call
965 * blk_end_request() for parts of the original function.
966 * This prevents code duplication in drivers.
968 extern bool blk_update_request(struct request *rq, int error,
969 unsigned int nr_bytes);
970 extern void blk_finish_request(struct request *rq, int error);
971 extern bool blk_end_request(struct request *rq, int error,
972 unsigned int nr_bytes);
973 extern void blk_end_request_all(struct request *rq, int error);
974 extern bool blk_end_request_cur(struct request *rq, int error);
975 extern bool blk_end_request_err(struct request *rq, int error);
976 extern bool __blk_end_request(struct request *rq, int error,
977 unsigned int nr_bytes);
978 extern void __blk_end_request_all(struct request *rq, int error);
979 extern bool __blk_end_request_cur(struct request *rq, int error);
980 extern bool __blk_end_request_err(struct request *rq, int error);
982 extern void blk_complete_request(struct request *);
983 extern void __blk_complete_request(struct request *);
984 extern void blk_abort_request(struct request *);
985 extern void blk_unprep_request(struct request *);
988 * Access functions for manipulating queue properties
990 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
991 spinlock_t *lock, int node_id);
992 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
993 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
994 request_fn_proc *, spinlock_t *);
995 extern void blk_cleanup_queue(struct request_queue *);
996 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
997 extern void blk_queue_bounce_limit(struct request_queue *, u64);
998 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
999 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1000 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1001 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1002 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1003 unsigned int max_discard_sectors);
1004 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1005 unsigned int max_write_same_sectors);
1006 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
1007 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1008 extern void blk_queue_alignment_offset(struct request_queue *q,
1009 unsigned int alignment);
1010 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1011 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1012 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1013 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1014 extern void blk_set_default_limits(struct queue_limits *lim);
1015 extern void blk_set_stacking_limits(struct queue_limits *lim);
1016 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1018 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1020 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1022 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1023 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1024 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1025 extern int blk_queue_dma_drain(struct request_queue *q,
1026 dma_drain_needed_fn *dma_drain_needed,
1027 void *buf, unsigned int size);
1028 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1029 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1030 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1031 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1032 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1033 extern void blk_queue_dma_alignment(struct request_queue *, int);
1034 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1035 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1036 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1037 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1038 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1039 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1040 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1042 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1043 extern void blk_dump_rq_flags(struct request *, char *);
1044 extern long nr_blockdev_pages(void);
1046 bool __must_check blk_get_queue(struct request_queue *);
1047 struct request_queue *blk_alloc_queue(gfp_t);
1048 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1049 extern void blk_put_queue(struct request_queue *);
1050 extern void blk_set_queue_dying(struct request_queue *);
1053 * block layer runtime pm functions
1056 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1057 extern int blk_pre_runtime_suspend(struct request_queue *q);
1058 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1059 extern void blk_pre_runtime_resume(struct request_queue *q);
1060 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1061 extern void blk_set_runtime_active(struct request_queue *q);
1063 static inline void blk_pm_runtime_init(struct request_queue *q,
1064 struct device *dev) {}
1065 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1069 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1070 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1071 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1072 extern inline void blk_set_runtime_active(struct request_queue *q) {}
1076 * blk_plug permits building a queue of related requests by holding the I/O
1077 * fragments for a short period. This allows merging of sequential requests
1078 * into single larger request. As the requests are moved from a per-task list to
1079 * the device's request_queue in a batch, this results in improved scalability
1080 * as the lock contention for request_queue lock is reduced.
1082 * It is ok not to disable preemption when adding the request to the plug list
1083 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1084 * the plug list when the task sleeps by itself. For details, please see
1085 * schedule() where blk_schedule_flush_plug() is called.
1088 struct list_head list; /* requests */
1089 struct list_head mq_list; /* blk-mq requests */
1090 struct list_head cb_list; /* md requires an unplug callback */
1092 #define BLK_MAX_REQUEST_COUNT 16
1095 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1096 struct blk_plug_cb {
1097 struct list_head list;
1098 blk_plug_cb_fn callback;
1101 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1102 void *data, int size);
1103 extern void blk_start_plug(struct blk_plug *);
1104 extern void blk_finish_plug(struct blk_plug *);
1105 extern void blk_flush_plug_list(struct blk_plug *, bool);
1107 static inline void blk_flush_plug(struct task_struct *tsk)
1109 struct blk_plug *plug = tsk->plug;
1112 blk_flush_plug_list(plug, false);
1115 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1117 struct blk_plug *plug = tsk->plug;
1120 blk_flush_plug_list(plug, true);
1123 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1125 struct blk_plug *plug = tsk->plug;
1128 (!list_empty(&plug->list) ||
1129 !list_empty(&plug->mq_list) ||
1130 !list_empty(&plug->cb_list));
1136 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1137 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1138 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1139 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1140 extern void blk_queue_free_tags(struct request_queue *);
1141 extern int blk_queue_resize_tags(struct request_queue *, int);
1142 extern void blk_queue_invalidate_tags(struct request_queue *);
1143 extern struct blk_queue_tag *blk_init_tags(int, int);
1144 extern void blk_free_tags(struct blk_queue_tag *);
1146 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1149 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1151 return bqt->tag_index[tag];
1154 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1156 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1157 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1158 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1159 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1160 sector_t nr_sects, gfp_t gfp_mask, int op_flags,
1162 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1163 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1164 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1165 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1166 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1167 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1169 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1170 nr_blocks << (sb->s_blocksize_bits - 9),
1173 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1174 sector_t nr_blocks, gfp_t gfp_mask)
1176 return blkdev_issue_zeroout(sb->s_bdev,
1177 block << (sb->s_blocksize_bits - 9),
1178 nr_blocks << (sb->s_blocksize_bits - 9),
1182 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1184 enum blk_default_limits {
1185 BLK_MAX_SEGMENTS = 128,
1186 BLK_SAFE_MAX_SECTORS = 255,
1187 BLK_DEF_MAX_SECTORS = 2560,
1188 BLK_MAX_SEGMENT_SIZE = 65536,
1189 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1192 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1194 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1196 return q->limits.bounce_pfn;
1199 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1201 return q->limits.seg_boundary_mask;
1204 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1206 return q->limits.virt_boundary_mask;
1209 static inline unsigned int queue_max_sectors(struct request_queue *q)
1211 return q->limits.max_sectors;
1214 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1216 return q->limits.max_hw_sectors;
1219 static inline unsigned short queue_max_segments(struct request_queue *q)
1221 return q->limits.max_segments;
1224 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1226 return q->limits.max_segment_size;
1229 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1233 if (q && q->limits.logical_block_size)
1234 retval = q->limits.logical_block_size;
1239 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1241 return queue_logical_block_size(bdev_get_queue(bdev));
1244 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1246 return q->limits.physical_block_size;
1249 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1251 return queue_physical_block_size(bdev_get_queue(bdev));
1254 static inline unsigned int queue_io_min(struct request_queue *q)
1256 return q->limits.io_min;
1259 static inline int bdev_io_min(struct block_device *bdev)
1261 return queue_io_min(bdev_get_queue(bdev));
1264 static inline unsigned int queue_io_opt(struct request_queue *q)
1266 return q->limits.io_opt;
1269 static inline int bdev_io_opt(struct block_device *bdev)
1271 return queue_io_opt(bdev_get_queue(bdev));
1274 static inline int queue_alignment_offset(struct request_queue *q)
1276 if (q->limits.misaligned)
1279 return q->limits.alignment_offset;
1282 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1284 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1285 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
1287 return (granularity + lim->alignment_offset - alignment) % granularity;
1290 static inline int bdev_alignment_offset(struct block_device *bdev)
1292 struct request_queue *q = bdev_get_queue(bdev);
1294 if (q->limits.misaligned)
1297 if (bdev != bdev->bd_contains)
1298 return bdev->bd_part->alignment_offset;
1300 return q->limits.alignment_offset;
1303 static inline int queue_discard_alignment(struct request_queue *q)
1305 if (q->limits.discard_misaligned)
1308 return q->limits.discard_alignment;
1311 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1313 unsigned int alignment, granularity, offset;
1315 if (!lim->max_discard_sectors)
1318 /* Why are these in bytes, not sectors? */
1319 alignment = lim->discard_alignment >> 9;
1320 granularity = lim->discard_granularity >> 9;
1324 /* Offset of the partition start in 'granularity' sectors */
1325 offset = sector_div(sector, granularity);
1327 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1328 offset = (granularity + alignment - offset) % granularity;
1330 /* Turn it back into bytes, gaah */
1334 static inline int bdev_discard_alignment(struct block_device *bdev)
1336 struct request_queue *q = bdev_get_queue(bdev);
1338 if (bdev != bdev->bd_contains)
1339 return bdev->bd_part->discard_alignment;
1341 return q->limits.discard_alignment;
1344 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1346 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1352 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1354 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1357 static inline unsigned int bdev_write_same(struct block_device *bdev)
1359 struct request_queue *q = bdev_get_queue(bdev);
1362 return q->limits.max_write_same_sectors;
1367 static inline int queue_dma_alignment(struct request_queue *q)
1369 return q ? q->dma_alignment : 511;
1372 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1375 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1376 return !(addr & alignment) && !(len & alignment);
1379 /* assumes size > 256 */
1380 static inline unsigned int blksize_bits(unsigned int size)
1382 unsigned int bits = 8;
1386 } while (size > 256);
1390 static inline unsigned int block_size(struct block_device *bdev)
1392 return bdev->bd_block_size;
1395 static inline bool queue_flush_queueable(struct request_queue *q)
1397 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags);
1400 typedef struct {struct page *v;} Sector;
1402 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1404 static inline void put_dev_sector(Sector p)
1409 static inline bool __bvec_gap_to_prev(struct request_queue *q,
1410 struct bio_vec *bprv, unsigned int offset)
1413 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1417 * Check if adding a bio_vec after bprv with offset would create a gap in
1418 * the SG list. Most drivers don't care about this, but some do.
1420 static inline bool bvec_gap_to_prev(struct request_queue *q,
1421 struct bio_vec *bprv, unsigned int offset)
1423 if (!queue_virt_boundary(q))
1425 return __bvec_gap_to_prev(q, bprv, offset);
1428 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1431 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1432 struct bio_vec pb, nb;
1434 bio_get_last_bvec(prev, &pb);
1435 bio_get_first_bvec(next, &nb);
1437 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1443 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1445 return bio_will_gap(req->q, req->biotail, bio);
1448 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1450 return bio_will_gap(req->q, bio, req->bio);
1454 int kblockd_schedule_work(struct work_struct *work);
1455 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1456 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1458 #ifdef CONFIG_BLK_CGROUP
1460 * This should not be using sched_clock(). A real patch is in progress
1461 * to fix this up, until that is in place we need to disable preemption
1462 * around sched_clock() in this function and set_io_start_time_ns().
1464 static inline void set_start_time_ns(struct request *req)
1467 req->start_time_ns = sched_clock();
1471 static inline void set_io_start_time_ns(struct request *req)
1474 req->io_start_time_ns = sched_clock();
1478 static inline uint64_t rq_start_time_ns(struct request *req)
1480 return req->start_time_ns;
1483 static inline uint64_t rq_io_start_time_ns(struct request *req)
1485 return req->io_start_time_ns;
1488 static inline void set_start_time_ns(struct request *req) {}
1489 static inline void set_io_start_time_ns(struct request *req) {}
1490 static inline uint64_t rq_start_time_ns(struct request *req)
1494 static inline uint64_t rq_io_start_time_ns(struct request *req)
1500 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1501 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1502 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1503 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1505 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1507 enum blk_integrity_flags {
1508 BLK_INTEGRITY_VERIFY = 1 << 0,
1509 BLK_INTEGRITY_GENERATE = 1 << 1,
1510 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1511 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1514 struct blk_integrity_iter {
1518 unsigned int data_size;
1519 unsigned short interval;
1520 const char *disk_name;
1523 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1525 struct blk_integrity_profile {
1526 integrity_processing_fn *generate_fn;
1527 integrity_processing_fn *verify_fn;
1531 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1532 extern void blk_integrity_unregister(struct gendisk *);
1533 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1534 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1535 struct scatterlist *);
1536 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1537 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1539 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1542 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1544 struct blk_integrity *bi = &disk->queue->integrity;
1553 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1555 return blk_get_integrity(bdev->bd_disk);
1558 static inline bool blk_integrity_rq(struct request *rq)
1560 return rq->cmd_flags & REQ_INTEGRITY;
1563 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1566 q->limits.max_integrity_segments = segs;
1569 static inline unsigned short
1570 queue_max_integrity_segments(struct request_queue *q)
1572 return q->limits.max_integrity_segments;
1575 static inline bool integrity_req_gap_back_merge(struct request *req,
1578 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1579 struct bio_integrity_payload *bip_next = bio_integrity(next);
1581 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1582 bip_next->bip_vec[0].bv_offset);
1585 static inline bool integrity_req_gap_front_merge(struct request *req,
1588 struct bio_integrity_payload *bip = bio_integrity(bio);
1589 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1591 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1592 bip_next->bip_vec[0].bv_offset);
1595 #else /* CONFIG_BLK_DEV_INTEGRITY */
1598 struct block_device;
1600 struct blk_integrity;
1602 static inline int blk_integrity_rq(struct request *rq)
1606 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1611 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1613 struct scatterlist *s)
1617 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1621 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1625 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1629 static inline void blk_integrity_register(struct gendisk *d,
1630 struct blk_integrity *b)
1633 static inline void blk_integrity_unregister(struct gendisk *d)
1636 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1640 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1644 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1650 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1657 static inline bool integrity_req_gap_back_merge(struct request *req,
1662 static inline bool integrity_req_gap_front_merge(struct request *req,
1668 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1671 * struct blk_dax_ctl - control and output parameters for ->direct_access
1672 * @sector: (input) offset relative to a block_device
1673 * @addr: (output) kernel virtual address for @sector populated by driver
1674 * @pfn: (output) page frame number for @addr populated by driver
1675 * @size: (input) number of bytes requested
1677 struct blk_dax_ctl {
1684 struct block_device_operations {
1685 int (*open) (struct block_device *, fmode_t);
1686 void (*release) (struct gendisk *, fmode_t);
1687 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1688 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1689 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1690 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
1692 unsigned int (*check_events) (struct gendisk *disk,
1693 unsigned int clearing);
1694 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1695 int (*media_changed) (struct gendisk *);
1696 void (*unlock_native_capacity) (struct gendisk *);
1697 int (*revalidate_disk) (struct gendisk *);
1698 int (*getgeo)(struct block_device *, struct hd_geometry *);
1699 /* this callback is with swap_lock and sometimes page table lock held */
1700 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1701 struct module *owner;
1702 const struct pr_ops *pr_ops;
1705 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1707 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1708 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1709 struct writeback_control *);
1710 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *);
1711 extern int bdev_dax_supported(struct super_block *, int);
1712 extern bool bdev_dax_capable(struct block_device *);
1713 #else /* CONFIG_BLOCK */
1715 struct block_device;
1718 * stubs for when the block layer is configured out
1720 #define buffer_heads_over_limit 0
1722 static inline long nr_blockdev_pages(void)
1730 static inline void blk_start_plug(struct blk_plug *plug)
1734 static inline void blk_finish_plug(struct blk_plug *plug)
1738 static inline void blk_flush_plug(struct task_struct *task)
1742 static inline void blk_schedule_flush_plug(struct task_struct *task)
1747 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1752 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1753 sector_t *error_sector)
1758 #endif /* CONFIG_BLOCK */