1 #ifndef _LINUX_BLKDEV_H
2 #define _LINUX_BLKDEV_H
4 #include <linux/sched.h>
8 #include <linux/major.h>
9 #include <linux/genhd.h>
10 #include <linux/list.h>
11 #include <linux/llist.h>
12 #include <linux/timer.h>
13 #include <linux/workqueue.h>
14 #include <linux/pagemap.h>
15 #include <linux/backing-dev.h>
16 #include <linux/wait.h>
17 #include <linux/mempool.h>
18 #include <linux/bio.h>
19 #include <linux/stringify.h>
20 #include <linux/gfp.h>
21 #include <linux/bsg.h>
22 #include <linux/smp.h>
23 #include <linux/rcupdate.h>
25 #include <asm/scatterlist.h>
28 struct scsi_ioctl_command;
31 struct elevator_queue;
32 struct request_pm_state;
39 #define BLKDEV_MIN_RQ 4
40 #define BLKDEV_MAX_RQ 128 /* Default maximum */
43 * Maximum number of blkcg policies allowed to be registered concurrently.
44 * Defined here to simplify include dependency.
46 #define BLKCG_MAX_POLS 2
49 typedef void (rq_end_io_fn)(struct request *, int);
51 #define BLK_RL_SYNCFULL (1U << 0)
52 #define BLK_RL_ASYNCFULL (1U << 1)
55 struct request_queue *q; /* the queue this rl belongs to */
56 #ifdef CONFIG_BLK_CGROUP
57 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
60 * count[], starved[], and wait[] are indexed by
61 * BLK_RW_SYNC/BLK_RW_ASYNC
66 wait_queue_head_t wait[2];
71 * request command types
73 enum rq_cmd_type_bits {
74 REQ_TYPE_FS = 1, /* fs request */
75 REQ_TYPE_BLOCK_PC, /* scsi command */
76 REQ_TYPE_SENSE, /* sense request */
77 REQ_TYPE_PM_SUSPEND, /* suspend request */
78 REQ_TYPE_PM_RESUME, /* resume request */
79 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */
80 REQ_TYPE_SPECIAL, /* driver defined type */
82 * for ATA/ATAPI devices. this really doesn't belong here, ide should
83 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
84 * private REQ_LB opcodes to differentiate what type of request this is
86 REQ_TYPE_ATA_TASKFILE,
90 #define BLK_MAX_CDB 16
93 * try to put the fields that are referenced together in the same cacheline.
94 * if you modify this structure, be sure to check block/blk-core.c:blk_rq_init()
98 struct list_head queuelist;
100 struct call_single_data csd;
101 struct work_struct mq_flush_work;
102 unsigned long fifo_time;
105 struct request_queue *q;
106 struct blk_mq_ctx *mq_ctx;
109 enum rq_cmd_type_bits cmd_type;
110 unsigned long atomic_flags;
114 /* the following two fields are internal, NEVER access directly */
115 unsigned int __data_len; /* total data len */
116 sector_t __sector; /* sector cursor */
121 struct hlist_node hash; /* merge hash */
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 */
170 char *buffer; /* kaddr of the current segment if available */
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 static inline unsigned short req_get_ioprio(struct request *req)
208 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
209 * requests. Some step values could eventually be made generic.
211 struct request_pm_state
213 /* PM state machine step value, currently driver specific */
215 /* requested PM state value (S1, S2, S3, S4, ...) */
217 void* data; /* for driver use */
220 #include <linux/elevator.h>
222 struct blk_queue_ctx;
224 typedef void (request_fn_proc) (struct request_queue *q);
225 typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
226 typedef int (prep_rq_fn) (struct request_queue *, struct request *);
227 typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
230 struct bvec_merge_data {
231 struct block_device *bi_bdev;
236 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
238 typedef void (softirq_done_fn)(struct request *);
239 typedef int (dma_drain_needed_fn)(struct request *);
240 typedef int (lld_busy_fn) (struct request_queue *q);
241 typedef int (bsg_job_fn) (struct bsg_job *);
243 enum blk_eh_timer_return {
249 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
251 enum blk_queue_state {
256 struct blk_queue_tag {
257 struct request **tag_index; /* map of busy tags */
258 unsigned long *tag_map; /* bit map of free/busy tags */
259 int busy; /* current depth */
260 int max_depth; /* what we will send to device */
261 int real_max_depth; /* what the array can hold */
262 atomic_t refcnt; /* map can be shared */
265 #define BLK_SCSI_MAX_CMDS (256)
266 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
268 struct queue_limits {
269 unsigned long bounce_pfn;
270 unsigned long seg_boundary_mask;
272 unsigned int max_hw_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_write_same_sectors;
281 unsigned int discard_granularity;
282 unsigned int discard_alignment;
284 unsigned short logical_block_size;
285 unsigned short max_segments;
286 unsigned short max_integrity_segments;
288 unsigned char misaligned;
289 unsigned char discard_misaligned;
290 unsigned char cluster;
291 unsigned char discard_zeroes_data;
292 unsigned char raid_partial_stripes_expensive;
295 struct request_queue {
297 * Together with queue_head for cacheline sharing
299 struct list_head queue_head;
300 struct request *last_merge;
301 struct elevator_queue *elevator;
302 int nr_rqs[2]; /* # allocated [a]sync rqs */
303 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
306 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
307 * is used, root blkg allocates from @q->root_rl and all other
308 * blkgs from their own blkg->rl. Which one to use should be
309 * determined using bio_request_list().
311 struct request_list root_rl;
313 request_fn_proc *request_fn;
314 make_request_fn *make_request_fn;
315 prep_rq_fn *prep_rq_fn;
316 unprep_rq_fn *unprep_rq_fn;
317 merge_bvec_fn *merge_bvec_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 *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_PM_RUNTIME
391 unsigned int nr_pending;
397 unsigned long nr_requests; /* Max # of requests */
398 unsigned int nr_congestion_on;
399 unsigned int nr_congestion_off;
400 unsigned int nr_batching;
402 unsigned int dma_drain_size;
403 void *dma_drain_buffer;
404 unsigned int dma_pad_mask;
405 unsigned int dma_alignment;
407 struct blk_queue_tag *queue_tags;
408 struct list_head tag_busy_list;
410 unsigned int nr_sorted;
411 unsigned int in_flight[2];
413 * Number of active block driver functions for which blk_drain_queue()
414 * must wait. Must be incremented around functions that unlock the
415 * queue_lock internally, e.g. scsi_request_fn().
417 unsigned int request_fn_active;
419 unsigned int rq_timeout;
420 struct timer_list timeout;
421 struct list_head timeout_list;
423 struct list_head icq_list;
424 #ifdef CONFIG_BLK_CGROUP
425 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
426 struct blkcg_gq *root_blkg;
427 struct list_head blkg_list;
430 struct queue_limits limits;
435 unsigned int sg_timeout;
436 unsigned int sg_reserved_size;
438 #ifdef CONFIG_BLK_DEV_IO_TRACE
439 struct blk_trace *blk_trace;
442 * for flush operations
444 unsigned int flush_flags;
445 unsigned int flush_not_queueable:1;
446 unsigned int flush_queue_delayed:1;
447 unsigned int flush_pending_idx:1;
448 unsigned int flush_running_idx:1;
449 unsigned long flush_pending_since;
450 struct list_head flush_queue[2];
451 struct list_head flush_data_in_flight;
452 struct request *flush_rq;
453 spinlock_t mq_flush_lock;
455 struct mutex sysfs_lock;
459 #if defined(CONFIG_BLK_DEV_BSG)
460 bsg_job_fn *bsg_job_fn;
462 struct bsg_class_device bsg_dev;
465 #ifdef CONFIG_BLK_DEV_THROTTLING
467 struct throtl_data *td;
469 struct rcu_head rcu_head;
470 wait_queue_head_t mq_freeze_wq;
471 struct percpu_counter mq_usage_counter;
472 struct list_head all_q_node;
475 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
476 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
477 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
478 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
479 #define QUEUE_FLAG_DYING 5 /* queue being torn down */
480 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
481 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
482 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
483 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
484 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
485 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
486 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
487 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
488 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
489 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
490 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
491 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
492 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
493 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
494 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
495 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
497 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
498 (1 << QUEUE_FLAG_STACKABLE) | \
499 (1 << QUEUE_FLAG_SAME_COMP) | \
500 (1 << QUEUE_FLAG_ADD_RANDOM))
502 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
503 (1 << QUEUE_FLAG_SAME_COMP))
505 static inline void queue_lockdep_assert_held(struct request_queue *q)
508 lockdep_assert_held(q->queue_lock);
511 static inline void queue_flag_set_unlocked(unsigned int flag,
512 struct request_queue *q)
514 __set_bit(flag, &q->queue_flags);
517 static inline int queue_flag_test_and_clear(unsigned int flag,
518 struct request_queue *q)
520 queue_lockdep_assert_held(q);
522 if (test_bit(flag, &q->queue_flags)) {
523 __clear_bit(flag, &q->queue_flags);
530 static inline int queue_flag_test_and_set(unsigned int flag,
531 struct request_queue *q)
533 queue_lockdep_assert_held(q);
535 if (!test_bit(flag, &q->queue_flags)) {
536 __set_bit(flag, &q->queue_flags);
543 static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
545 queue_lockdep_assert_held(q);
546 __set_bit(flag, &q->queue_flags);
549 static inline void queue_flag_clear_unlocked(unsigned int flag,
550 struct request_queue *q)
552 __clear_bit(flag, &q->queue_flags);
555 static inline int queue_in_flight(struct request_queue *q)
557 return q->in_flight[0] + q->in_flight[1];
560 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
562 queue_lockdep_assert_held(q);
563 __clear_bit(flag, &q->queue_flags);
566 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
567 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
568 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
569 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
570 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
571 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
572 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
573 #define blk_queue_noxmerges(q) \
574 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
575 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
576 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
577 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
578 #define blk_queue_stackable(q) \
579 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
580 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
581 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
582 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
584 #define blk_noretry_request(rq) \
585 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
586 REQ_FAILFAST_DRIVER))
588 #define blk_account_rq(rq) \
589 (((rq)->cmd_flags & REQ_STARTED) && \
590 ((rq)->cmd_type == REQ_TYPE_FS))
592 #define blk_pm_request(rq) \
593 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
594 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
596 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
597 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
598 /* rq->queuelist of dequeued request must be list_empty() */
599 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
601 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
603 #define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
605 static inline unsigned int blk_queue_cluster(struct request_queue *q)
607 return q->limits.cluster;
611 * We regard a request as sync, if either a read or a sync write
613 static inline bool rw_is_sync(unsigned int rw_flags)
615 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
618 static inline bool rq_is_sync(struct request *rq)
620 return rw_is_sync(rq->cmd_flags);
623 static inline bool blk_rl_full(struct request_list *rl, bool sync)
625 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
627 return rl->flags & flag;
630 static inline void blk_set_rl_full(struct request_list *rl, bool sync)
632 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
637 static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
639 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
644 static inline bool rq_mergeable(struct request *rq)
646 if (rq->cmd_type != REQ_TYPE_FS)
649 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
655 static inline bool blk_check_merge_flags(unsigned int flags1,
658 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
661 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
664 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
670 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
672 if (bio_data(a) == bio_data(b))
679 * q->prep_rq_fn return values
681 #define BLKPREP_OK 0 /* serve it */
682 #define BLKPREP_KILL 1 /* fatal error, kill */
683 #define BLKPREP_DEFER 2 /* leave on queue */
685 extern unsigned long blk_max_low_pfn, blk_max_pfn;
688 * standard bounce addresses:
690 * BLK_BOUNCE_HIGH : bounce all highmem pages
691 * BLK_BOUNCE_ANY : don't bounce anything
692 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
695 #if BITS_PER_LONG == 32
696 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
698 #define BLK_BOUNCE_HIGH -1ULL
700 #define BLK_BOUNCE_ANY (-1ULL)
701 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
704 * default timeout for SG_IO if none specified
706 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
707 #define BLK_MIN_SG_TIMEOUT (7 * HZ)
710 extern int init_emergency_isa_pool(void);
711 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
713 static inline int init_emergency_isa_pool(void)
717 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
720 #endif /* CONFIG_MMU */
726 unsigned long offset;
731 struct req_iterator {
732 struct bvec_iter iter;
736 /* This should not be used directly - use rq_for_each_segment */
737 #define for_each_bio(_bio) \
738 for (; _bio; _bio = _bio->bi_next)
739 #define __rq_for_each_bio(_bio, rq) \
741 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
743 #define rq_for_each_segment(bvl, _rq, _iter) \
744 __rq_for_each_bio(_iter.bio, _rq) \
745 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
747 #define rq_iter_last(bvec, _iter) \
748 (_iter.bio->bi_next == NULL && \
749 bio_iter_last(bvec, _iter.iter))
751 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
752 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
754 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
755 extern void rq_flush_dcache_pages(struct request *rq);
757 static inline void rq_flush_dcache_pages(struct request *rq)
762 extern int blk_register_queue(struct gendisk *disk);
763 extern void blk_unregister_queue(struct gendisk *disk);
764 extern void generic_make_request(struct bio *bio);
765 extern void blk_rq_init(struct request_queue *q, struct request *rq);
766 extern void blk_put_request(struct request *);
767 extern void __blk_put_request(struct request_queue *, struct request *);
768 extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
769 extern struct request *blk_make_request(struct request_queue *, struct bio *,
771 extern void blk_requeue_request(struct request_queue *, struct request *);
772 extern void blk_add_request_payload(struct request *rq, struct page *page,
774 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
775 extern int blk_lld_busy(struct request_queue *q);
776 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
777 struct bio_set *bs, gfp_t gfp_mask,
778 int (*bio_ctr)(struct bio *, struct bio *, void *),
780 extern void blk_rq_unprep_clone(struct request *rq);
781 extern int blk_insert_cloned_request(struct request_queue *q,
783 extern void blk_delay_queue(struct request_queue *, unsigned long);
784 extern void blk_recount_segments(struct request_queue *, struct bio *);
785 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
786 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
787 unsigned int, void __user *);
788 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
789 unsigned int, void __user *);
790 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
791 struct scsi_ioctl_command __user *);
793 extern void blk_queue_bio(struct request_queue *q, struct bio *bio);
796 * A queue has just exitted congestion. Note this in the global counter of
797 * congested queues, and wake up anyone who was waiting for requests to be
800 static inline void blk_clear_queue_congested(struct request_queue *q, int sync)
802 clear_bdi_congested(&q->backing_dev_info, sync);
806 * A queue has just entered congestion. Flag that in the queue's VM-visible
807 * state flags and increment the global gounter of congested queues.
809 static inline void blk_set_queue_congested(struct request_queue *q, int sync)
811 set_bdi_congested(&q->backing_dev_info, sync);
814 extern void blk_start_queue(struct request_queue *q);
815 extern void blk_stop_queue(struct request_queue *q);
816 extern void blk_sync_queue(struct request_queue *q);
817 extern void __blk_stop_queue(struct request_queue *q);
818 extern void __blk_run_queue(struct request_queue *q);
819 extern void blk_run_queue(struct request_queue *);
820 extern void blk_run_queue_async(struct request_queue *q);
821 extern int blk_rq_map_user(struct request_queue *, struct request *,
822 struct rq_map_data *, void __user *, unsigned long,
824 extern int blk_rq_unmap_user(struct bio *);
825 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
826 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
827 struct rq_map_data *, struct sg_iovec *, int,
828 unsigned int, gfp_t);
829 extern int blk_execute_rq(struct request_queue *, struct gendisk *,
830 struct request *, int);
831 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
832 struct request *, int, rq_end_io_fn *);
834 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
836 return bdev->bd_disk->queue;
840 * blk_rq_pos() : the current sector
841 * blk_rq_bytes() : bytes left in the entire request
842 * blk_rq_cur_bytes() : bytes left in the current segment
843 * blk_rq_err_bytes() : bytes left till the next error boundary
844 * blk_rq_sectors() : sectors left in the entire request
845 * blk_rq_cur_sectors() : sectors left in the current segment
847 static inline sector_t blk_rq_pos(const struct request *rq)
852 static inline unsigned int blk_rq_bytes(const struct request *rq)
854 return rq->__data_len;
857 static inline int blk_rq_cur_bytes(const struct request *rq)
859 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
862 extern unsigned int blk_rq_err_bytes(const struct request *rq);
864 static inline unsigned int blk_rq_sectors(const struct request *rq)
866 return blk_rq_bytes(rq) >> 9;
869 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
871 return blk_rq_cur_bytes(rq) >> 9;
874 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
875 unsigned int cmd_flags)
877 if (unlikely(cmd_flags & REQ_DISCARD))
878 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
880 if (unlikely(cmd_flags & REQ_WRITE_SAME))
881 return q->limits.max_write_same_sectors;
883 return q->limits.max_sectors;
886 static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
888 struct request_queue *q = rq->q;
890 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
891 return q->limits.max_hw_sectors;
893 return blk_queue_get_max_sectors(q, rq->cmd_flags);
896 static inline unsigned int blk_rq_count_bios(struct request *rq)
898 unsigned int nr_bios = 0;
901 __rq_for_each_bio(bio, rq)
908 * Request issue related functions.
910 extern struct request *blk_peek_request(struct request_queue *q);
911 extern void blk_start_request(struct request *rq);
912 extern struct request *blk_fetch_request(struct request_queue *q);
915 * Request completion related functions.
917 * blk_update_request() completes given number of bytes and updates
918 * the request without completing it.
920 * blk_end_request() and friends. __blk_end_request() must be called
921 * with the request queue spinlock acquired.
923 * Several drivers define their own end_request and call
924 * blk_end_request() for parts of the original function.
925 * This prevents code duplication in drivers.
927 extern bool blk_update_request(struct request *rq, int error,
928 unsigned int nr_bytes);
929 extern bool blk_end_request(struct request *rq, int error,
930 unsigned int nr_bytes);
931 extern void blk_end_request_all(struct request *rq, int error);
932 extern bool blk_end_request_cur(struct request *rq, int error);
933 extern bool blk_end_request_err(struct request *rq, int error);
934 extern bool __blk_end_request(struct request *rq, int error,
935 unsigned int nr_bytes);
936 extern void __blk_end_request_all(struct request *rq, int error);
937 extern bool __blk_end_request_cur(struct request *rq, int error);
938 extern bool __blk_end_request_err(struct request *rq, int error);
940 extern void blk_complete_request(struct request *);
941 extern void __blk_complete_request(struct request *);
942 extern void blk_abort_request(struct request *);
943 extern void blk_unprep_request(struct request *);
946 * Access functions for manipulating queue properties
948 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
949 spinlock_t *lock, int node_id);
950 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
951 extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
952 request_fn_proc *, spinlock_t *);
953 extern void blk_cleanup_queue(struct request_queue *);
954 extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
955 extern void blk_queue_bounce_limit(struct request_queue *, u64);
956 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
957 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
958 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
959 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
960 extern void blk_queue_max_discard_sectors(struct request_queue *q,
961 unsigned int max_discard_sectors);
962 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
963 unsigned int max_write_same_sectors);
964 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
965 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
966 extern void blk_queue_alignment_offset(struct request_queue *q,
967 unsigned int alignment);
968 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
969 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
970 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
971 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
972 extern void blk_set_default_limits(struct queue_limits *lim);
973 extern void blk_set_stacking_limits(struct queue_limits *lim);
974 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
976 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
978 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
980 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
981 extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
982 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
983 extern int blk_queue_dma_drain(struct request_queue *q,
984 dma_drain_needed_fn *dma_drain_needed,
985 void *buf, unsigned int size);
986 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
987 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
988 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
989 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
990 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
991 extern void blk_queue_dma_alignment(struct request_queue *, int);
992 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
993 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
994 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
995 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
996 extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
997 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
998 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1000 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1001 extern int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
1002 struct scatterlist *sglist);
1003 extern void blk_dump_rq_flags(struct request *, char *);
1004 extern long nr_blockdev_pages(void);
1006 bool __must_check blk_get_queue(struct request_queue *);
1007 struct request_queue *blk_alloc_queue(gfp_t);
1008 struct request_queue *blk_alloc_queue_node(gfp_t, int);
1009 extern void blk_put_queue(struct request_queue *);
1012 * block layer runtime pm functions
1014 #ifdef CONFIG_PM_RUNTIME
1015 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1016 extern int blk_pre_runtime_suspend(struct request_queue *q);
1017 extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1018 extern void blk_pre_runtime_resume(struct request_queue *q);
1019 extern void blk_post_runtime_resume(struct request_queue *q, int err);
1021 static inline void blk_pm_runtime_init(struct request_queue *q,
1022 struct device *dev) {}
1023 static inline int blk_pre_runtime_suspend(struct request_queue *q)
1027 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1028 static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1029 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1033 * blk_plug permits building a queue of related requests by holding the I/O
1034 * fragments for a short period. This allows merging of sequential requests
1035 * into single larger request. As the requests are moved from a per-task list to
1036 * the device's request_queue in a batch, this results in improved scalability
1037 * as the lock contention for request_queue lock is reduced.
1039 * It is ok not to disable preemption when adding the request to the plug list
1040 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1041 * the plug list when the task sleeps by itself. For details, please see
1042 * schedule() where blk_schedule_flush_plug() is called.
1045 unsigned long magic; /* detect uninitialized use-cases */
1046 struct list_head list; /* requests */
1047 struct list_head mq_list; /* blk-mq requests */
1048 struct list_head cb_list; /* md requires an unplug callback */
1050 #define BLK_MAX_REQUEST_COUNT 16
1053 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1054 struct blk_plug_cb {
1055 struct list_head list;
1056 blk_plug_cb_fn callback;
1059 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1060 void *data, int size);
1061 extern void blk_start_plug(struct blk_plug *);
1062 extern void blk_finish_plug(struct blk_plug *);
1063 extern void blk_flush_plug_list(struct blk_plug *, bool);
1065 static inline void blk_flush_plug(struct task_struct *tsk)
1067 struct blk_plug *plug = tsk->plug;
1070 blk_flush_plug_list(plug, false);
1073 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1075 struct blk_plug *plug = tsk->plug;
1078 blk_flush_plug_list(plug, true);
1081 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1083 struct blk_plug *plug = tsk->plug;
1086 (!list_empty(&plug->list) ||
1087 !list_empty(&plug->mq_list) ||
1088 !list_empty(&plug->cb_list));
1094 #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED)
1095 extern int blk_queue_start_tag(struct request_queue *, struct request *);
1096 extern struct request *blk_queue_find_tag(struct request_queue *, int);
1097 extern void blk_queue_end_tag(struct request_queue *, struct request *);
1098 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
1099 extern void blk_queue_free_tags(struct request_queue *);
1100 extern int blk_queue_resize_tags(struct request_queue *, int);
1101 extern void blk_queue_invalidate_tags(struct request_queue *);
1102 extern struct blk_queue_tag *blk_init_tags(int);
1103 extern void blk_free_tags(struct blk_queue_tag *);
1105 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1108 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1110 return bqt->tag_index[tag];
1113 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1115 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1116 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1117 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1118 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1119 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1120 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1121 sector_t nr_sects, gfp_t gfp_mask);
1122 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1123 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1125 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1126 nr_blocks << (sb->s_blocksize_bits - 9),
1129 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1130 sector_t nr_blocks, gfp_t gfp_mask)
1132 return blkdev_issue_zeroout(sb->s_bdev,
1133 block << (sb->s_blocksize_bits - 9),
1134 nr_blocks << (sb->s_blocksize_bits - 9),
1138 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1140 enum blk_default_limits {
1141 BLK_MAX_SEGMENTS = 128,
1142 BLK_SAFE_MAX_SECTORS = 255,
1143 BLK_DEF_MAX_SECTORS = 1024,
1144 BLK_MAX_SEGMENT_SIZE = 65536,
1145 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1148 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1150 static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1152 return q->limits.bounce_pfn;
1155 static inline unsigned long queue_segment_boundary(struct request_queue *q)
1157 return q->limits.seg_boundary_mask;
1160 static inline unsigned int queue_max_sectors(struct request_queue *q)
1162 return q->limits.max_sectors;
1165 static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1167 return q->limits.max_hw_sectors;
1170 static inline unsigned short queue_max_segments(struct request_queue *q)
1172 return q->limits.max_segments;
1175 static inline unsigned int queue_max_segment_size(struct request_queue *q)
1177 return q->limits.max_segment_size;
1180 static inline unsigned short queue_logical_block_size(struct request_queue *q)
1184 if (q && q->limits.logical_block_size)
1185 retval = q->limits.logical_block_size;
1190 static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1192 return queue_logical_block_size(bdev_get_queue(bdev));
1195 static inline unsigned int queue_physical_block_size(struct request_queue *q)
1197 return q->limits.physical_block_size;
1200 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1202 return queue_physical_block_size(bdev_get_queue(bdev));
1205 static inline unsigned int queue_io_min(struct request_queue *q)
1207 return q->limits.io_min;
1210 static inline int bdev_io_min(struct block_device *bdev)
1212 return queue_io_min(bdev_get_queue(bdev));
1215 static inline unsigned int queue_io_opt(struct request_queue *q)
1217 return q->limits.io_opt;
1220 static inline int bdev_io_opt(struct block_device *bdev)
1222 return queue_io_opt(bdev_get_queue(bdev));
1225 static inline int queue_alignment_offset(struct request_queue *q)
1227 if (q->limits.misaligned)
1230 return q->limits.alignment_offset;
1233 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1235 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1236 unsigned int alignment = (sector << 9) & (granularity - 1);
1238 return (granularity + lim->alignment_offset - alignment)
1239 & (granularity - 1);
1242 static inline int bdev_alignment_offset(struct block_device *bdev)
1244 struct request_queue *q = bdev_get_queue(bdev);
1246 if (q->limits.misaligned)
1249 if (bdev != bdev->bd_contains)
1250 return bdev->bd_part->alignment_offset;
1252 return q->limits.alignment_offset;
1255 static inline int queue_discard_alignment(struct request_queue *q)
1257 if (q->limits.discard_misaligned)
1260 return q->limits.discard_alignment;
1263 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1265 unsigned int alignment, granularity, offset;
1267 if (!lim->max_discard_sectors)
1270 /* Why are these in bytes, not sectors? */
1271 alignment = lim->discard_alignment >> 9;
1272 granularity = lim->discard_granularity >> 9;
1276 /* Offset of the partition start in 'granularity' sectors */
1277 offset = sector_div(sector, granularity);
1279 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1280 offset = (granularity + alignment - offset) % granularity;
1282 /* Turn it back into bytes, gaah */
1286 static inline int bdev_discard_alignment(struct block_device *bdev)
1288 struct request_queue *q = bdev_get_queue(bdev);
1290 if (bdev != bdev->bd_contains)
1291 return bdev->bd_part->discard_alignment;
1293 return q->limits.discard_alignment;
1296 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1298 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1304 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1306 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1309 static inline unsigned int bdev_write_same(struct block_device *bdev)
1311 struct request_queue *q = bdev_get_queue(bdev);
1314 return q->limits.max_write_same_sectors;
1319 static inline int queue_dma_alignment(struct request_queue *q)
1321 return q ? q->dma_alignment : 511;
1324 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1327 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1328 return !(addr & alignment) && !(len & alignment);
1331 /* assumes size > 256 */
1332 static inline unsigned int blksize_bits(unsigned int size)
1334 unsigned int bits = 8;
1338 } while (size > 256);
1342 static inline unsigned int block_size(struct block_device *bdev)
1344 return bdev->bd_block_size;
1347 static inline bool queue_flush_queueable(struct request_queue *q)
1349 return !q->flush_not_queueable;
1352 typedef struct {struct page *v;} Sector;
1354 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1356 static inline void put_dev_sector(Sector p)
1358 page_cache_release(p.v);
1362 int kblockd_schedule_work(struct request_queue *q, struct work_struct *work);
1363 int kblockd_schedule_delayed_work(struct request_queue *q, struct delayed_work *dwork, unsigned long delay);
1365 #ifdef CONFIG_BLK_CGROUP
1367 * This should not be using sched_clock(). A real patch is in progress
1368 * to fix this up, until that is in place we need to disable preemption
1369 * around sched_clock() in this function and set_io_start_time_ns().
1371 static inline void set_start_time_ns(struct request *req)
1374 req->start_time_ns = sched_clock();
1378 static inline void set_io_start_time_ns(struct request *req)
1381 req->io_start_time_ns = sched_clock();
1385 static inline uint64_t rq_start_time_ns(struct request *req)
1387 return req->start_time_ns;
1390 static inline uint64_t rq_io_start_time_ns(struct request *req)
1392 return req->io_start_time_ns;
1395 static inline void set_start_time_ns(struct request *req) {}
1396 static inline void set_io_start_time_ns(struct request *req) {}
1397 static inline uint64_t rq_start_time_ns(struct request *req)
1401 static inline uint64_t rq_io_start_time_ns(struct request *req)
1407 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1408 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1409 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1410 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1412 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1414 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */
1415 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */
1417 struct blk_integrity_exchg {
1421 unsigned int data_size;
1422 unsigned short sector_size;
1423 const char *disk_name;
1426 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
1427 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
1428 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
1429 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);
1431 struct blk_integrity {
1432 integrity_gen_fn *generate_fn;
1433 integrity_vrfy_fn *verify_fn;
1434 integrity_set_tag_fn *set_tag_fn;
1435 integrity_get_tag_fn *get_tag_fn;
1437 unsigned short flags;
1438 unsigned short tuple_size;
1439 unsigned short sector_size;
1440 unsigned short tag_size;
1444 struct kobject kobj;
1447 extern bool blk_integrity_is_initialized(struct gendisk *);
1448 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1449 extern void blk_integrity_unregister(struct gendisk *);
1450 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1451 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1452 struct scatterlist *);
1453 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1454 extern int blk_integrity_merge_rq(struct request_queue *, struct request *,
1456 extern int blk_integrity_merge_bio(struct request_queue *, struct request *,
1460 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1462 return bdev->bd_disk->integrity;
1465 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1467 return disk->integrity;
1470 static inline int blk_integrity_rq(struct request *rq)
1472 if (rq->bio == NULL)
1475 return bio_integrity(rq->bio);
1478 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1481 q->limits.max_integrity_segments = segs;
1484 static inline unsigned short
1485 queue_max_integrity_segments(struct request_queue *q)
1487 return q->limits.max_integrity_segments;
1490 #else /* CONFIG_BLK_DEV_INTEGRITY */
1493 struct block_device;
1495 struct blk_integrity;
1497 static inline int blk_integrity_rq(struct request *rq)
1501 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1506 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1508 struct scatterlist *s)
1512 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1516 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1520 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1524 static inline int blk_integrity_register(struct gendisk *d,
1525 struct blk_integrity *b)
1529 static inline void blk_integrity_unregister(struct gendisk *d)
1532 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1536 static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1540 static inline int blk_integrity_merge_rq(struct request_queue *rq,
1546 static inline int blk_integrity_merge_bio(struct request_queue *rq,
1552 static inline bool blk_integrity_is_initialized(struct gendisk *g)
1557 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1559 struct block_device_operations {
1560 int (*open) (struct block_device *, fmode_t);
1561 void (*release) (struct gendisk *, fmode_t);
1562 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1563 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1564 int (*direct_access) (struct block_device *, sector_t,
1565 void **, unsigned long *);
1566 unsigned int (*check_events) (struct gendisk *disk,
1567 unsigned int clearing);
1568 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1569 int (*media_changed) (struct gendisk *);
1570 void (*unlock_native_capacity) (struct gendisk *);
1571 int (*revalidate_disk) (struct gendisk *);
1572 int (*getgeo)(struct block_device *, struct hd_geometry *);
1573 /* this callback is with swap_lock and sometimes page table lock held */
1574 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1575 struct module *owner;
1578 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1580 #else /* CONFIG_BLOCK */
1582 * stubs for when the block layer is configured out
1584 #define buffer_heads_over_limit 0
1586 static inline long nr_blockdev_pages(void)
1594 static inline void blk_start_plug(struct blk_plug *plug)
1598 static inline void blk_finish_plug(struct blk_plug *plug)
1602 static inline void blk_flush_plug(struct task_struct *task)
1606 static inline void blk_schedule_flush_plug(struct task_struct *task)
1611 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1616 #endif /* CONFIG_BLOCK */