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
50 typedef void (rq_end_io_fn)(struct request *, int);
52 #define BLK_RL_SYNCFULL (1U << 0)
53 #define BLK_RL_ASYNCFULL (1U << 1)
56 struct request_queue *q; /* the queue this rl belongs to */
57 #ifdef CONFIG_BLK_CGROUP
58 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
61 * count[], starved[], and wait[] are indexed by
62 * BLK_RW_SYNC/BLK_RW_ASYNC
67 wait_queue_head_t wait[2];
72 * request command types
74 enum rq_cmd_type_bits {
75 REQ_TYPE_FS = 1, /* fs request */
76 REQ_TYPE_BLOCK_PC, /* scsi command */
77 REQ_TYPE_DRV_PRIV, /* driver defined types from here */
80 #define BLK_MAX_CDB 16
83 * Try to put the fields that are referenced together in the same cacheline.
85 * If you modify this structure, make sure to update blk_rq_init() and
86 * especially blk_mq_rq_ctx_init() to take care of the added fields.
89 struct list_head queuelist;
91 struct call_single_data csd;
95 struct request_queue *q;
96 struct blk_mq_ctx *mq_ctx;
101 unsigned long atomic_flags;
103 /* the following two fields are internal, NEVER access directly */
104 unsigned int __data_len; /* total data len */
105 sector_t __sector; /* sector cursor */
111 * The hash is used inside the scheduler, and killed once the
112 * request reaches the dispatch list. The ipi_list is only used
113 * to queue the request for softirq completion, which is long
114 * after the request has been unhashed (and even removed from
115 * the dispatch list).
118 struct hlist_node hash; /* merge hash */
119 struct list_head ipi_list;
123 * The rb_node is only used inside the io scheduler, requests
124 * are pruned when moved to the dispatch queue. So let the
125 * completion_data share space with the rb_node.
128 struct rb_node rb_node; /* sort/lookup */
129 void *completion_data;
133 * Three pointers are available for the IO schedulers, if they need
134 * more they have to dynamically allocate it. Flush requests are
135 * never put on the IO scheduler. So let the flush fields share
136 * space with the elevator data.
146 struct list_head list;
147 rq_end_io_fn *saved_end_io;
151 struct gendisk *rq_disk;
152 struct hd_struct *part;
153 unsigned long start_time;
154 #ifdef CONFIG_BLK_CGROUP
155 struct request_list *rl; /* rl this rq is alloced from */
156 unsigned long long start_time_ns;
157 unsigned long long io_start_time_ns; /* when passed to hardware */
159 /* Number of scatter-gather DMA addr+len pairs after
160 * physical address coalescing is performed.
162 unsigned short nr_phys_segments;
163 #if defined(CONFIG_BLK_DEV_INTEGRITY)
164 unsigned short nr_integrity_segments;
167 unsigned short ioprio;
169 void *special; /* opaque pointer available for LLD use */
175 * when request is used as a packet command carrier
177 unsigned char __cmd[BLK_MAX_CDB];
179 unsigned short cmd_len;
181 unsigned int extra_len; /* length of alignment and padding */
182 unsigned int sense_len;
183 unsigned int resid_len; /* residual count */
186 unsigned long deadline;
187 struct list_head timeout_list;
188 unsigned int timeout;
192 * completion callback.
194 rq_end_io_fn *end_io;
198 struct request *next_rq;
201 #define REQ_OP_SHIFT (8 * sizeof(u64) - REQ_OP_BITS)
202 #define req_op(req) ((req)->cmd_flags >> REQ_OP_SHIFT)
204 #define req_set_op(req, op) do { \
205 WARN_ON(op >= (1 << REQ_OP_BITS)); \
206 (req)->cmd_flags &= ((1ULL << REQ_OP_SHIFT) - 1); \
207 (req)->cmd_flags |= ((u64) (op) << REQ_OP_SHIFT); \
210 #define req_set_op_attrs(req, op, flags) do { \
211 req_set_op(req, op); \
212 (req)->cmd_flags |= flags; \
215 static inline bool blk_rq_is_passthrough(struct request *rq)
217 return rq->cmd_type != REQ_TYPE_FS;
220 static inline unsigned short req_get_ioprio(struct request *req)
225 #include <linux/elevator.h>
227 struct blk_queue_ctx;
229 typedef void (request_fn_proc) (struct request_queue *q);
230 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
231 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
232 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
235 typedef void (softirq_done_fn)(struct request *);
236 typedef int (dma_drain_needed_fn)(struct request *);
237 typedef int (lld_busy_fn) (struct request_queue *q);
238 typedef int (bsg_job_fn) (struct bsg_job *);
240 enum blk_eh_timer_return {
246 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
248 enum blk_queue_state {
253 struct blk_queue_tag {
254 struct request **tag_index; /* map of busy tags */
255 unsigned long *tag_map; /* bit map of free/busy tags */
256 int busy; /* current depth */
257 int max_depth; /* what we will send to device */
258 int real_max_depth; /* what the array can hold */
259 atomic_t refcnt; /* map can be shared */
260 int alloc_policy; /* tag allocation policy */
261 int next_tag; /* next tag */
263 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
264 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
266 #define BLK_SCSI_MAX_CMDS (256)
267 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
269 struct queue_limits {
270 unsigned long bounce_pfn;
271 unsigned long seg_boundary_mask;
272 unsigned long virt_boundary_mask;
274 unsigned int max_hw_sectors;
275 unsigned int max_dev_sectors;
276 unsigned int chunk_sectors;
277 unsigned int max_sectors;
278 unsigned int max_segment_size;
279 unsigned int physical_block_size;
280 unsigned int logical_block_size;
281 unsigned int alignment_offset;
284 unsigned int max_discard_sectors;
285 unsigned int max_hw_discard_sectors;
286 unsigned int max_write_same_sectors;
287 unsigned int discard_granularity;
288 unsigned int discard_alignment;
290 unsigned short max_segments;
291 unsigned short max_integrity_segments;
293 unsigned char misaligned;
294 unsigned char discard_misaligned;
295 unsigned char cluster;
296 unsigned char discard_zeroes_data;
297 unsigned char raid_partial_stripes_expensive;
300 struct request_queue {
302 * Together with queue_head for cacheline sharing
304 struct list_head queue_head;
305 struct request *last_merge;
306 struct elevator_queue *elevator;
307 int nr_rqs[2]; /* # allocated [a]sync rqs */
308 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
311 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
312 * is used, root blkg allocates from @q->root_rl and all other
313 * blkgs from their own blkg->rl. Which one to use should be
314 * determined using bio_request_list().
316 struct request_list root_rl;
318 request_fn_proc *request_fn;
319 make_request_fn *make_request_fn;
320 prep_rq_fn *prep_rq_fn;
321 unprep_rq_fn *unprep_rq_fn;
322 softirq_done_fn *softirq_done_fn;
323 rq_timed_out_fn *rq_timed_out_fn;
324 dma_drain_needed_fn *dma_drain_needed;
325 lld_busy_fn *lld_busy_fn;
327 struct blk_mq_ops *mq_ops;
329 unsigned int *mq_map;
332 struct blk_mq_ctx __percpu *queue_ctx;
333 unsigned int nr_queues;
335 /* hw dispatch queues */
336 struct blk_mq_hw_ctx **queue_hw_ctx;
337 unsigned int nr_hw_queues;
340 * Dispatch queue sorting
343 struct request *boundary_rq;
346 * Delayed queue handling
348 struct delayed_work delay_work;
350 struct backing_dev_info backing_dev_info;
353 * The queue owner gets to use this for whatever they like.
354 * ll_rw_blk doesn't touch it.
359 * various queue flags, see QUEUE_* below
361 unsigned long queue_flags;
364 * ida allocated id for this queue. Used to index queues from
370 * queue needs bounce pages for pages above this limit
375 * protects queue structures from reentrancy. ->__queue_lock should
376 * _never_ be used directly, it is queue private. always use
379 spinlock_t __queue_lock;
380 spinlock_t *queue_lock;
390 struct kobject mq_kobj;
392 #ifdef CONFIG_BLK_DEV_INTEGRITY
393 struct blk_integrity integrity;
394 #endif /* CONFIG_BLK_DEV_INTEGRITY */
399 unsigned int nr_pending;
405 unsigned long nr_requests; /* Max # of requests */
406 unsigned int nr_congestion_on;
407 unsigned int nr_congestion_off;
408 unsigned int nr_batching;
410 unsigned int dma_drain_size;
411 void *dma_drain_buffer;
412 unsigned int dma_pad_mask;
413 unsigned int dma_alignment;
415 struct blk_queue_tag *queue_tags;
416 struct list_head tag_busy_list;
418 unsigned int nr_sorted;
419 unsigned int in_flight[2];
421 * Number of active block driver functions for which blk_drain_queue()
422 * must wait. Must be incremented around functions that unlock the
423 * queue_lock internally, e.g. scsi_request_fn().
425 unsigned int request_fn_active;
427 unsigned int rq_timeout;
428 struct timer_list timeout;
429 struct work_struct timeout_work;
430 struct list_head timeout_list;
432 struct list_head icq_list;
433 #ifdef CONFIG_BLK_CGROUP
434 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
435 struct blkcg_gq *root_blkg;
436 struct list_head blkg_list;
439 struct queue_limits limits;
444 unsigned int sg_timeout;
445 unsigned int sg_reserved_size;
447 #ifdef CONFIG_BLK_DEV_IO_TRACE
448 struct blk_trace __rcu *blk_trace;
449 struct mutex blk_trace_mutex;
452 * for flush operations
454 struct blk_flush_queue *fq;
456 struct list_head requeue_list;
457 spinlock_t requeue_lock;
458 struct delayed_work requeue_work;
460 struct mutex sysfs_lock;
463 atomic_t mq_freeze_depth;
465 #if defined(CONFIG_BLK_DEV_BSG)
466 bsg_job_fn *bsg_job_fn;
468 struct bsg_class_device bsg_dev;
471 #ifdef CONFIG_BLK_DEV_THROTTLING
473 struct throtl_data *td;
475 struct rcu_head rcu_head;
476 wait_queue_head_t mq_freeze_wq;
477 struct percpu_ref q_usage_counter;
478 struct list_head all_q_node;
480 struct blk_mq_tag_set *tag_set;
481 struct list_head tag_set_list;
482 struct bio_set *bio_split;
484 bool mq_sysfs_init_done;
487 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
488 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
489 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
490 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
491 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
492 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
493 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
494 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
495 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
496 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
497 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
498 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
499 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
500 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
501 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
502 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
503 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
504 #define QUEUE_FLAG_SECERASE 17 /* supports secure erase */
505 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
506 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
507 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
508 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
509 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
510 #define QUEUE_FLAG_WC 23 /* Write back caching */
511 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */
512 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
513 #define QUEUE_FLAG_DAX 26 /* device supports DAX */
515 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
516 (1 << QUEUE_FLAG_STACKABLE) | \
517 (1 << QUEUE_FLAG_SAME_COMP) | \
518 (1 << QUEUE_FLAG_ADD_RANDOM))
520 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
521 (1 << QUEUE_FLAG_STACKABLE) | \
522 (1 << QUEUE_FLAG_SAME_COMP) | \
523 (1 << QUEUE_FLAG_POLL))
525 static inline void queue_lockdep_assert_held(struct request_queue *q)
528 lockdep_assert_held(q->queue_lock);
531 static inline void queue_flag_set_unlocked(unsigned int flag,
532 struct request_queue *q)
534 __set_bit(flag, &q->queue_flags);
537 static inline int queue_flag_test_and_clear(unsigned int flag,
538 struct request_queue *q)
540 queue_lockdep_assert_held(q);
542 if (test_bit(flag, &q->queue_flags)) {
543 __clear_bit(flag, &q->queue_flags);
550 static inline int queue_flag_test_and_set(unsigned int flag,
551 struct request_queue *q)
553 queue_lockdep_assert_held(q);
555 if (!test_bit(flag, &q->queue_flags)) {
556 __set_bit(flag, &q->queue_flags);
563 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
565 queue_lockdep_assert_held(q);
566 __set_bit(flag, &q->queue_flags);
569 static inline void queue_flag_clear_unlocked(unsigned int flag,
570 struct request_queue *q)
572 __clear_bit(flag, &q->queue_flags);
575 static inline int queue_in_flight(struct request_queue *q)
577 return q->in_flight[0] + q->in_flight[1];
580 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
582 queue_lockdep_assert_held(q);
583 __clear_bit(flag, &q->queue_flags);
586 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
587 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
588 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
589 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
590 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
591 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
592 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
593 #define blk_queue_noxmerges(q) \
594 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
595 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
596 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
597 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
598 #define blk_queue_stackable(q) \
599 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
600 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
601 #define blk_queue_secure_erase(q) \
602 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
603 #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
605 #define blk_noretry_request(rq) \
606 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
607 REQ_FAILFAST_DRIVER))
609 #define blk_account_rq(rq) \
610 (((rq)->cmd_flags & REQ_STARTED) && \
611 ((rq)->cmd_type == REQ_TYPE_FS))
613 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
614 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
615 /* rq->queuelist of dequeued request must be list_empty() */
616 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
618 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
620 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
623 * Driver can handle struct request, if it either has an old style
624 * request_fn defined, or is blk-mq based.
626 static inline bool queue_is_rq_based(struct request_queue *q)
628 return q->request_fn || q->mq_ops;
631 static inline unsigned int blk_queue_cluster(struct request_queue *q)
633 return q->limits.cluster;
637 * We regard a request as sync, if either a read or a sync write
639 static inline bool rw_is_sync(int op, unsigned int rw_flags)
641 return op == REQ_OP_READ || (rw_flags & REQ_SYNC);
644 static inline bool rq_is_sync(struct request *rq)
646 return rw_is_sync(req_op(rq), rq->cmd_flags);
649 static inline bool blk_rl_full(struct request_list *rl, bool sync)
651 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
653 return rl->flags & flag;
656 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
658 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
663 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
665 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
670 static inline bool rq_mergeable(struct request *rq)
672 if (blk_rq_is_passthrough(rq))
675 if (req_op(rq) == REQ_OP_FLUSH)
678 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
684 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
686 if (bio_data(a) == bio_data(b))
693 * q->prep_rq_fn return values
696 BLKPREP_OK, /* serve it */
697 BLKPREP_KILL, /* fatal error, kill, return -EIO */
698 BLKPREP_DEFER, /* leave on queue */
699 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */
702 extern unsigned long blk_max_low_pfn, blk_max_pfn;
705 * standard bounce addresses:
707 * BLK_BOUNCE_HIGH : bounce all highmem pages
708 * BLK_BOUNCE_ANY : don't bounce anything
709 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
712 #if BITS_PER_LONG == 32
713 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
715 #define BLK_BOUNCE_HIGH -1ULL
717 #define BLK_BOUNCE_ANY (-1ULL)
718 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
721 * default timeout for SG_IO if none specified
723 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
724 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
727 extern int init_emergency_isa_pool(void);
728 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
730 static inline int init_emergency_isa_pool(void)
734 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
737 #endif /* CONFIG_MMU */
743 unsigned long offset;
748 struct req_iterator {
749 struct bvec_iter iter;
753 /* This should not be used directly - use rq_for_each_segment */
754 #define for_each_bio(_bio) \
755 for (; _bio; _bio = _bio->bi_next)
756 #define __rq_for_each_bio(_bio, rq) \
758 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
760 #define rq_for_each_segment(bvl, _rq, _iter) \
761 __rq_for_each_bio(_iter.bio, _rq) \
762 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
764 #define rq_iter_last(bvec, _iter) \
765 (_iter.bio->bi_next == NULL && \
766 bio_iter_last(bvec, _iter.iter))
768 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
769 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
771 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
772 extern void rq_flush_dcache_pages(struct request *rq);
774 static inline void rq_flush_dcache_pages(struct request *rq)
780 #define vfs_msg(sb, level, fmt, ...) \
781 __vfs_msg(sb, level, fmt, ##__VA_ARGS__)
783 #define vfs_msg(sb, level, fmt, ...) \
785 no_printk(fmt, ##__VA_ARGS__); \
786 __vfs_msg(sb, "", " "); \
790 extern int blk_register_queue(struct gendisk *disk);
791 extern void blk_unregister_queue(struct gendisk *disk);
792 extern blk_qc_t generic_make_request(struct bio *bio);
793 extern void blk_rq_init(struct request_queue *q, struct request *rq);
794 extern void blk_put_request(struct request *);
795 extern void __blk_put_request(struct request_queue *, struct request *);
796 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
797 extern void blk_rq_set_block_pc(struct request *);
798 extern void blk_requeue_request(struct request_queue *, struct request *);
799 extern void blk_add_request_payload(struct request *rq, struct page *page,
800 int offset, unsigned int len);
801 extern int blk_lld_busy(struct request_queue *q);
802 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
803 struct bio_set *bs, gfp_t gfp_mask,
804 int (*bio_ctr)(struct bio *, struct bio *, void *),
806 extern void blk_rq_unprep_clone(struct request *rq);
807 extern int blk_insert_cloned_request(struct request_queue *q,
809 extern int blk_rq_append_bio(struct request *rq, struct bio *bio);
810 extern void blk_delay_queue(struct request_queue *, unsigned long);
811 extern void blk_queue_split(struct request_queue *, struct bio **,
813 extern void blk_recount_segments(struct request_queue *, struct bio *);
814 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
815 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
816 unsigned int, void __user *);
817 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
818 unsigned int, void __user *);
819 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
820 struct scsi_ioctl_command __user *);
822 extern int blk_queue_enter(struct request_queue *q, bool nowait);
823 extern void blk_queue_exit(struct request_queue *q);
824 extern void blk_start_queue(struct request_queue *q);
825 extern void blk_start_queue_async(struct request_queue *q);
826 extern void blk_stop_queue(struct request_queue *q);
827 extern void blk_sync_queue(struct request_queue *q);
828 extern void __blk_stop_queue(struct request_queue *q);
829 extern void __blk_run_queue(struct request_queue *q);
830 extern void __blk_run_queue_uncond(struct request_queue *q);
831 extern void blk_run_queue(struct request_queue *);
832 extern void blk_run_queue_async(struct request_queue *q);
833 extern int blk_rq_map_user(struct request_queue *, struct request *,
834 struct rq_map_data *, void __user *, unsigned long,
836 extern int blk_rq_unmap_user(struct bio *);
837 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
838 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
839 struct rq_map_data *, const struct iov_iter *,
841 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
842 struct request *, int);
843 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
844 struct request *, int, rq_end_io_fn *);
846 bool blk_poll(struct request_queue *q, blk_qc_t cookie);
848 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
850 return bdev->bd_disk->queue; /* this is never NULL */
854 * The basic unit of block I/O is a sector. It is used in a number of contexts
855 * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
856 * bytes. Variables of type sector_t represent an offset or size that is a
857 * multiple of 512 bytes. Hence these two constants.
860 #define SECTOR_SHIFT 9
863 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
867 * blk_rq_pos() : the current sector
868 * blk_rq_bytes() : bytes left in the entire request
869 * blk_rq_cur_bytes() : bytes left in the current segment
870 * blk_rq_err_bytes() : bytes left till the next error boundary
871 * blk_rq_sectors() : sectors left in the entire request
872 * blk_rq_cur_sectors() : sectors left in the current segment
874 static inline sector_t blk_rq_pos(const struct request *rq)
879 static inline unsigned int blk_rq_bytes(const struct request *rq)
881 return rq->__data_len;
884 static inline int blk_rq_cur_bytes(const struct request *rq)
886 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
889 extern unsigned int blk_rq_err_bytes(const struct request *rq);
891 static inline unsigned int blk_rq_sectors(const struct request *rq)
893 return blk_rq_bytes(rq) >> SECTOR_SHIFT;
896 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
898 return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
901 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
904 if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
905 return min(q->limits.max_discard_sectors,
906 UINT_MAX >> SECTOR_SHIFT);
908 if (unlikely(op == REQ_OP_WRITE_SAME))
909 return q->limits.max_write_same_sectors;
911 return q->limits.max_sectors;
915 * Return maximum size of a request at given offset. Only valid for
916 * file system requests.
918 static inline unsigned int blk_max_size_offset(struct request_queue *q,
921 if (!q->limits.chunk_sectors)
922 return q->limits.max_sectors;
924 return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
925 (offset & (q->limits.chunk_sectors - 1))));
928 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
931 struct request_queue *q = rq->q;
933 if (blk_rq_is_passthrough(rq))
934 return q->limits.max_hw_sectors;
936 if (!q->limits.chunk_sectors ||
937 req_op(rq) == REQ_OP_DISCARD ||
938 req_op(rq) == REQ_OP_SECURE_ERASE)
939 return blk_queue_get_max_sectors(q, req_op(rq));
941 return min(blk_max_size_offset(q, offset),
942 blk_queue_get_max_sectors(q, req_op(rq)));
945 static inline unsigned int blk_rq_count_bios(struct request *rq)
947 unsigned int nr_bios = 0;
950 __rq_for_each_bio(bio, rq)
957 * Request issue related functions.
959 extern struct request *blk_peek_request(struct request_queue *q);
960 extern void blk_start_request(struct request *rq);
961 extern struct request *blk_fetch_request(struct request_queue *q);
964 * Request completion related functions.
966 * blk_update_request() completes given number of bytes and updates
967 * the request without completing it.
969 * blk_end_request() and friends. __blk_end_request() must be called
970 * with the request queue spinlock acquired.
972 * Several drivers define their own end_request and call
973 * blk_end_request() for parts of the original function.
974 * This prevents code duplication in drivers.
976 extern bool blk_update_request(struct request *rq, int error,
977 unsigned int nr_bytes);
978 extern void blk_finish_request(struct request *rq, int error);
979 extern bool blk_end_request(struct request *rq, int error,
980 unsigned int nr_bytes);
981 extern void blk_end_request_all(struct request *rq, int error);
982 extern bool blk_end_request_cur(struct request *rq, int error);
983 extern bool blk_end_request_err(struct request *rq, int error);
984 extern bool __blk_end_request(struct request *rq, int error,
985 unsigned int nr_bytes);
986 extern void __blk_end_request_all(struct request *rq, int error);
987 extern bool __blk_end_request_cur(struct request *rq, int error);
988 extern bool __blk_end_request_err(struct request *rq, int error);
990 extern void blk_complete_request(struct request *);
991 extern void __blk_complete_request(struct request *);
992 extern void blk_abort_request(struct request *);
993 extern void blk_unprep_request(struct request *);
996 * Access functions for manipulating queue properties
998 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
999 spinlock_t *lock, int node_id);
1000 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
1001 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
1002 request_fn_proc *, spinlock_t *);
1003 extern void blk_cleanup_queue(struct request_queue *);
1004 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1005 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1006 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1007 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1008 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1009 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1010 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1011 unsigned int max_discard_sectors);
1012 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1013 unsigned int max_write_same_sectors);
1014 extern void blk_queue_logical_block_size(struct request_queue *, unsigned int);
1015 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1016 extern void blk_queue_alignment_offset(struct request_queue *q,
1017 unsigned int alignment);
1018 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1019 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1020 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1021 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1022 extern void blk_set_default_limits(struct queue_limits *lim);
1023 extern void blk_set_stacking_limits(struct queue_limits *lim);
1024 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1026 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1028 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1030 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1031 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1032 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1033 extern int blk_queue_dma_drain(struct request_queue *q,
1034 dma_drain_needed_fn *dma_drain_needed,
1035 void *buf, unsigned int size);
1036 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1037 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1038 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1039 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1040 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1041 extern void blk_queue_dma_alignment(struct request_queue *, int);
1042 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1043 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1044 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1045 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1046 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1047 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1048 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1050 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1051 extern void blk_dump_rq_flags(struct request *, char *);
1052 extern long nr_blockdev_pages(void);
1054 bool __must_check blk_get_queue(struct request_queue *);
1055 struct request_queue *blk_alloc_queue(gfp_t);
1056 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1057 extern void blk_put_queue(struct request_queue *);
1058 extern void blk_set_queue_dying(struct request_queue *);
1061 * block layer runtime pm functions
1064 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1065 extern int blk_pre_runtime_suspend(struct request_queue *q);
1066 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1067 extern void blk_pre_runtime_resume(struct request_queue *q);
1068 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1069 extern void blk_set_runtime_active(struct request_queue *q);
1071 static inline void blk_pm_runtime_init(struct request_queue *q,
1072 struct device *dev) {}
1073 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1077 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1078 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1079 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1080 static inline void blk_set_runtime_active(struct request_queue *q) {}
1084 * blk_plug permits building a queue of related requests by holding the I/O
1085 * fragments for a short period. This allows merging of sequential requests
1086 * into single larger request. As the requests are moved from a per-task list to
1087 * the device's request_queue in a batch, this results in improved scalability
1088 * as the lock contention for request_queue lock is reduced.
1090 * It is ok not to disable preemption when adding the request to the plug list
1091 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1092 * the plug list when the task sleeps by itself. For details, please see
1093 * schedule() where blk_schedule_flush_plug() is called.
1096 struct list_head list; /* requests */
1097 struct list_head mq_list; /* blk-mq requests */
1098 struct list_head cb_list; /* md requires an unplug callback */
1100 #define BLK_MAX_REQUEST_COUNT 16
1103 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1104 struct blk_plug_cb {
1105 struct list_head list;
1106 blk_plug_cb_fn callback;
1109 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1110 void *data, int size);
1111 extern void blk_start_plug(struct blk_plug *);
1112 extern void blk_finish_plug(struct blk_plug *);
1113 extern void blk_flush_plug_list(struct blk_plug *, bool);
1115 static inline void blk_flush_plug(struct task_struct *tsk)
1117 struct blk_plug *plug = tsk->plug;
1120 blk_flush_plug_list(plug, false);
1123 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1125 struct blk_plug *plug = tsk->plug;
1128 blk_flush_plug_list(plug, true);
1131 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1133 struct blk_plug *plug = tsk->plug;
1136 (!list_empty(&plug->list) ||
1137 !list_empty(&plug->mq_list) ||
1138 !list_empty(&plug->cb_list));
1144 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1145 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1146 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1147 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1148 extern void blk_queue_free_tags(struct request_queue *);
1149 extern int blk_queue_resize_tags(struct request_queue *, int);
1150 extern void blk_queue_invalidate_tags(struct request_queue *);
1151 extern struct blk_queue_tag *blk_init_tags(int, int);
1152 extern void blk_free_tags(struct blk_queue_tag *);
1154 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1157 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1159 return bqt->tag_index[tag];
1163 #define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */
1164 #define BLKDEV_DISCARD_ZERO (1 << 1) /* must reliably zero data */
1166 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1167 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1168 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1169 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1170 sector_t nr_sects, gfp_t gfp_mask, int flags,
1172 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1173 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1174 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1175 sector_t nr_sects, gfp_t gfp_mask, bool discard);
1176 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1177 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1179 return blkdev_issue_discard(sb->s_bdev,
1180 block << (sb->s_blocksize_bits -
1182 nr_blocks << (sb->s_blocksize_bits -
1186 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1187 sector_t nr_blocks, gfp_t gfp_mask)
1189 return blkdev_issue_zeroout(sb->s_bdev,
1190 block << (sb->s_blocksize_bits -
1192 nr_blocks << (sb->s_blocksize_bits -
1197 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1199 enum blk_default_limits {
1200 BLK_MAX_SEGMENTS = 128,
1201 BLK_SAFE_MAX_SECTORS = 255,
1202 BLK_DEF_MAX_SECTORS = 2560,
1203 BLK_MAX_SEGMENT_SIZE = 65536,
1204 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1207 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1209 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1211 return q->limits.bounce_pfn;
1214 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1216 return q->limits.seg_boundary_mask;
1219 static inline unsigned long queue_virt_boundary(struct request_queue *q)
1221 return q->limits.virt_boundary_mask;
1224 static inline unsigned int queue_max_sectors(struct request_queue *q)
1226 return q->limits.max_sectors;
1229 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1231 return q->limits.max_hw_sectors;
1234 static inline unsigned short queue_max_segments(struct request_queue *q)
1236 return q->limits.max_segments;
1239 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1241 return q->limits.max_segment_size;
1244 static inline unsigned queue_logical_block_size(struct request_queue *q)
1248 if (q && q->limits.logical_block_size)
1249 retval = q->limits.logical_block_size;
1254 static inline unsigned int bdev_logical_block_size(struct block_device *bdev)
1256 return queue_logical_block_size(bdev_get_queue(bdev));
1259 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1261 return q->limits.physical_block_size;
1264 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1266 return queue_physical_block_size(bdev_get_queue(bdev));
1269 static inline unsigned int queue_io_min(struct request_queue *q)
1271 return q->limits.io_min;
1274 static inline int bdev_io_min(struct block_device *bdev)
1276 return queue_io_min(bdev_get_queue(bdev));
1279 static inline unsigned int queue_io_opt(struct request_queue *q)
1281 return q->limits.io_opt;
1284 static inline int bdev_io_opt(struct block_device *bdev)
1286 return queue_io_opt(bdev_get_queue(bdev));
1289 static inline int queue_alignment_offset(struct request_queue *q)
1291 if (q->limits.misaligned)
1294 return q->limits.alignment_offset;
1297 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1299 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1300 unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1303 return (granularity + lim->alignment_offset - alignment) % granularity;
1306 static inline int bdev_alignment_offset(struct block_device *bdev)
1308 struct request_queue *q = bdev_get_queue(bdev);
1310 if (q->limits.misaligned)
1313 if (bdev != bdev->bd_contains)
1314 return bdev->bd_part->alignment_offset;
1316 return q->limits.alignment_offset;
1319 static inline int queue_discard_alignment(struct request_queue *q)
1321 if (q->limits.discard_misaligned)
1324 return q->limits.discard_alignment;
1327 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1329 unsigned int alignment, granularity, offset;
1331 if (!lim->max_discard_sectors)
1334 /* Why are these in bytes, not sectors? */
1335 alignment = lim->discard_alignment >> SECTOR_SHIFT;
1336 granularity = lim->discard_granularity >> SECTOR_SHIFT;
1340 /* Offset of the partition start in 'granularity' sectors */
1341 offset = sector_div(sector, granularity);
1343 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1344 offset = (granularity + alignment - offset) % granularity;
1346 /* Turn it back into bytes, gaah */
1347 return offset << SECTOR_SHIFT;
1350 static inline int bdev_discard_alignment(struct block_device *bdev)
1352 struct request_queue *q = bdev_get_queue(bdev);
1354 if (bdev != bdev->bd_contains)
1355 return bdev->bd_part->discard_alignment;
1357 return q->limits.discard_alignment;
1360 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1362 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1368 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1370 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1373 static inline unsigned int bdev_write_same(struct block_device *bdev)
1375 struct request_queue *q = bdev_get_queue(bdev);
1378 return q->limits.max_write_same_sectors;
1383 static inline int queue_dma_alignment(struct request_queue *q)
1385 return q ? q->dma_alignment : 511;
1388 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1391 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1392 return !(addr & alignment) && !(len & alignment);
1395 /* assumes size > 256 */
1396 static inline unsigned int blksize_bits(unsigned int size)
1398 unsigned int bits = 8;
1402 } while (size > 256);
1406 static inline unsigned int block_size(struct block_device *bdev)
1408 return bdev->bd_block_size;
1411 static inline bool queue_flush_queueable(struct request_queue *q)
1413 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags);
1416 typedef struct {struct page *v;} Sector;
1418 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1420 static inline void put_dev_sector(Sector p)
1425 static inline bool __bvec_gap_to_prev(struct request_queue *q,
1426 struct bio_vec *bprv, unsigned int offset)
1429 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1433 * Check if adding a bio_vec after bprv with offset would create a gap in
1434 * the SG list. Most drivers don't care about this, but some do.
1436 static inline bool bvec_gap_to_prev(struct request_queue *q,
1437 struct bio_vec *bprv, unsigned int offset)
1439 if (!queue_virt_boundary(q))
1441 return __bvec_gap_to_prev(q, bprv, offset);
1444 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1447 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1448 struct bio_vec pb, nb;
1450 bio_get_last_bvec(prev, &pb);
1451 bio_get_first_bvec(next, &nb);
1453 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1459 static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1461 return bio_will_gap(req->q, req->biotail, bio);
1464 static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1466 return bio_will_gap(req->q, bio, req->bio);
1469 int kblockd_schedule_work(struct work_struct *work);
1470 int kblockd_schedule_work_on(int cpu, struct work_struct *work);
1471 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1472 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1474 #ifdef CONFIG_BLK_CGROUP
1476 * This should not be using sched_clock(). A real patch is in progress
1477 * to fix this up, until that is in place we need to disable preemption
1478 * around sched_clock() in this function and set_io_start_time_ns().
1480 static inline void set_start_time_ns(struct request *req)
1483 req->start_time_ns = sched_clock();
1487 static inline void set_io_start_time_ns(struct request *req)
1490 req->io_start_time_ns = sched_clock();
1494 static inline uint64_t rq_start_time_ns(struct request *req)
1496 return req->start_time_ns;
1499 static inline uint64_t rq_io_start_time_ns(struct request *req)
1501 return req->io_start_time_ns;
1504 static inline void set_start_time_ns(struct request *req) {}
1505 static inline void set_io_start_time_ns(struct request *req) {}
1506 static inline uint64_t rq_start_time_ns(struct request *req)
1510 static inline uint64_t rq_io_start_time_ns(struct request *req)
1516 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1517 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1518 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1519 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1521 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1523 enum blk_integrity_flags {
1524 BLK_INTEGRITY_VERIFY = 1 << 0,
1525 BLK_INTEGRITY_GENERATE = 1 << 1,
1526 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1527 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1530 struct blk_integrity_iter {
1534 unsigned int data_size;
1535 unsigned short interval;
1536 const char *disk_name;
1539 typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
1541 struct blk_integrity_profile {
1542 integrity_processing_fn *generate_fn;
1543 integrity_processing_fn *verify_fn;
1547 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1548 extern void blk_integrity_unregister(struct gendisk *);
1549 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1550 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1551 struct scatterlist *);
1552 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1553 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1555 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1558 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1560 struct blk_integrity *bi = &disk->queue->integrity;
1569 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1571 return blk_get_integrity(bdev->bd_disk);
1574 static inline bool blk_integrity_rq(struct request *rq)
1576 return rq->cmd_flags & REQ_INTEGRITY;
1579 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1582 q->limits.max_integrity_segments = segs;
1585 static inline unsigned short
1586 queue_max_integrity_segments(struct request_queue *q)
1588 return q->limits.max_integrity_segments;
1591 static inline bool integrity_req_gap_back_merge(struct request *req,
1594 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1595 struct bio_integrity_payload *bip_next = bio_integrity(next);
1597 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1598 bip_next->bip_vec[0].bv_offset);
1601 static inline bool integrity_req_gap_front_merge(struct request *req,
1604 struct bio_integrity_payload *bip = bio_integrity(bio);
1605 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1607 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1608 bip_next->bip_vec[0].bv_offset);
1611 #else /* CONFIG_BLK_DEV_INTEGRITY */
1614 struct block_device;
1616 struct blk_integrity;
1618 static inline int blk_integrity_rq(struct request *rq)
1622 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1627 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1629 struct scatterlist *s)
1633 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1637 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1641 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1645 static inline void blk_integrity_register(struct gendisk *d,
1646 struct blk_integrity *b)
1649 static inline void blk_integrity_unregister(struct gendisk *d)
1652 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1656 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1660 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1666 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1673 static inline bool integrity_req_gap_back_merge(struct request *req,
1678 static inline bool integrity_req_gap_front_merge(struct request *req,
1684 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1687 * struct blk_dax_ctl - control and output parameters for ->direct_access
1688 * @sector: (input) offset relative to a block_device
1689 * @addr: (output) kernel virtual address for @sector populated by driver
1690 * @pfn: (output) page frame number for @addr populated by driver
1691 * @size: (input) number of bytes requested
1693 struct blk_dax_ctl {
1700 struct block_device_operations {
1701 int (*open) (struct block_device *, fmode_t);
1702 void (*release) (struct gendisk *, fmode_t);
1703 int (*rw_page)(struct block_device *, sector_t, struct page *, bool);
1704 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1705 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1706 long (*direct_access)(struct block_device *, sector_t, void **, pfn_t *,
1708 unsigned int (*check_events) (struct gendisk *disk,
1709 unsigned int clearing);
1710 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1711 int (*media_changed) (struct gendisk *);
1712 void (*unlock_native_capacity) (struct gendisk *);
1713 int (*revalidate_disk) (struct gendisk *);
1714 int (*getgeo)(struct block_device *, struct hd_geometry *);
1715 /* this callback is with swap_lock and sometimes page table lock held */
1716 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1717 struct module *owner;
1718 const struct pr_ops *pr_ops;
1721 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1723 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1724 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1725 struct writeback_control *);
1726 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *);
1727 extern int bdev_dax_supported(struct super_block *, int);
1728 extern bool bdev_dax_capable(struct block_device *);
1729 #else /* CONFIG_BLOCK */
1731 struct block_device;
1734 * stubs for when the block layer is configured out
1736 #define buffer_heads_over_limit 0
1738 static inline long nr_blockdev_pages(void)
1746 static inline void blk_start_plug(struct blk_plug *plug)
1750 static inline void blk_finish_plug(struct blk_plug *plug)
1754 static inline void blk_flush_plug(struct task_struct *task)
1758 static inline void blk_schedule_flush_plug(struct task_struct *task)
1763 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1768 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1769 sector_t *error_sector)
1774 #endif /* CONFIG_BLOCK */