xref: /linux-6.15/include/linux/blkdev.h (revision 926ee00e)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_BLKDEV_H
3 #define _LINUX_BLKDEV_H
4 
5 #include <linux/sched.h>
6 #include <linux/sched/clock.h>
7 #include <linux/major.h>
8 #include <linux/genhd.h>
9 #include <linux/list.h>
10 #include <linux/llist.h>
11 #include <linux/minmax.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>
27 #include <linux/blkzoned.h>
28 #include <linux/pm.h>
29 
30 struct module;
31 struct scsi_ioctl_command;
32 
33 struct request_queue;
34 struct elevator_queue;
35 struct blk_trace;
36 struct request;
37 struct sg_io_hdr;
38 struct bsg_job;
39 struct blkcg_gq;
40 struct blk_flush_queue;
41 struct pr_ops;
42 struct rq_qos;
43 struct blk_queue_stats;
44 struct blk_stat_callback;
45 struct blk_keyslot_manager;
46 
47 #define BLKDEV_MIN_RQ	4
48 #define BLKDEV_MAX_RQ	128	/* Default maximum */
49 
50 /* Must be consistent with blk_mq_poll_stats_bkt() */
51 #define BLK_MQ_POLL_STATS_BKTS 16
52 
53 /* Doing classic polling */
54 #define BLK_MQ_POLL_CLASSIC -1
55 
56 /*
57  * Maximum number of blkcg policies allowed to be registered concurrently.
58  * Defined here to simplify include dependency.
59  */
60 #define BLKCG_MAX_POLS		5
61 
62 typedef void (rq_end_io_fn)(struct request *, blk_status_t);
63 
64 /*
65  * request flags */
66 typedef __u32 __bitwise req_flags_t;
67 
68 /* drive already may have started this one */
69 #define RQF_STARTED		((__force req_flags_t)(1 << 1))
70 /* may not be passed by ioscheduler */
71 #define RQF_SOFTBARRIER		((__force req_flags_t)(1 << 3))
72 /* request for flush sequence */
73 #define RQF_FLUSH_SEQ		((__force req_flags_t)(1 << 4))
74 /* merge of different types, fail separately */
75 #define RQF_MIXED_MERGE		((__force req_flags_t)(1 << 5))
76 /* track inflight for MQ */
77 #define RQF_MQ_INFLIGHT		((__force req_flags_t)(1 << 6))
78 /* don't call prep for this one */
79 #define RQF_DONTPREP		((__force req_flags_t)(1 << 7))
80 /* vaguely specified driver internal error.  Ignored by the block layer */
81 #define RQF_FAILED		((__force req_flags_t)(1 << 10))
82 /* don't warn about errors */
83 #define RQF_QUIET		((__force req_flags_t)(1 << 11))
84 /* elevator private data attached */
85 #define RQF_ELVPRIV		((__force req_flags_t)(1 << 12))
86 /* account into disk and partition IO statistics */
87 #define RQF_IO_STAT		((__force req_flags_t)(1 << 13))
88 /* runtime pm request */
89 #define RQF_PM			((__force req_flags_t)(1 << 15))
90 /* on IO scheduler merge hash */
91 #define RQF_HASHED		((__force req_flags_t)(1 << 16))
92 /* track IO completion time */
93 #define RQF_STATS		((__force req_flags_t)(1 << 17))
94 /* Look at ->special_vec for the actual data payload instead of the
95    bio chain. */
96 #define RQF_SPECIAL_PAYLOAD	((__force req_flags_t)(1 << 18))
97 /* The per-zone write lock is held for this request */
98 #define RQF_ZONE_WRITE_LOCKED	((__force req_flags_t)(1 << 19))
99 /* already slept for hybrid poll */
100 #define RQF_MQ_POLL_SLEPT	((__force req_flags_t)(1 << 20))
101 /* ->timeout has been called, don't expire again */
102 #define RQF_TIMED_OUT		((__force req_flags_t)(1 << 21))
103 
104 /* flags that prevent us from merging requests: */
105 #define RQF_NOMERGE_FLAGS \
106 	(RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD)
107 
108 /*
109  * Request state for blk-mq.
110  */
111 enum mq_rq_state {
112 	MQ_RQ_IDLE		= 0,
113 	MQ_RQ_IN_FLIGHT		= 1,
114 	MQ_RQ_COMPLETE		= 2,
115 };
116 
117 /*
118  * Try to put the fields that are referenced together in the same cacheline.
119  *
120  * If you modify this structure, make sure to update blk_rq_init() and
121  * especially blk_mq_rq_ctx_init() to take care of the added fields.
122  */
123 struct request {
124 	struct request_queue *q;
125 	struct blk_mq_ctx *mq_ctx;
126 	struct blk_mq_hw_ctx *mq_hctx;
127 
128 	unsigned int cmd_flags;		/* op and common flags */
129 	req_flags_t rq_flags;
130 
131 	int tag;
132 	int internal_tag;
133 
134 	/* the following two fields are internal, NEVER access directly */
135 	unsigned int __data_len;	/* total data len */
136 	sector_t __sector;		/* sector cursor */
137 
138 	struct bio *bio;
139 	struct bio *biotail;
140 
141 	struct list_head queuelist;
142 
143 	/*
144 	 * The hash is used inside the scheduler, and killed once the
145 	 * request reaches the dispatch list. The ipi_list is only used
146 	 * to queue the request for softirq completion, which is long
147 	 * after the request has been unhashed (and even removed from
148 	 * the dispatch list).
149 	 */
150 	union {
151 		struct hlist_node hash;	/* merge hash */
152 		struct llist_node ipi_list;
153 	};
154 
155 	/*
156 	 * The rb_node is only used inside the io scheduler, requests
157 	 * are pruned when moved to the dispatch queue. So let the
158 	 * completion_data share space with the rb_node.
159 	 */
160 	union {
161 		struct rb_node rb_node;	/* sort/lookup */
162 		struct bio_vec special_vec;
163 		void *completion_data;
164 		int error_count; /* for legacy drivers, don't use */
165 	};
166 
167 	/*
168 	 * Three pointers are available for the IO schedulers, if they need
169 	 * more they have to dynamically allocate it.  Flush requests are
170 	 * never put on the IO scheduler. So let the flush fields share
171 	 * space with the elevator data.
172 	 */
173 	union {
174 		struct {
175 			struct io_cq		*icq;
176 			void			*priv[2];
177 		} elv;
178 
179 		struct {
180 			unsigned int		seq;
181 			struct list_head	list;
182 			rq_end_io_fn		*saved_end_io;
183 		} flush;
184 	};
185 
186 	struct gendisk *rq_disk;
187 	struct block_device *part;
188 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
189 	/* Time that the first bio started allocating this request. */
190 	u64 alloc_time_ns;
191 #endif
192 	/* Time that this request was allocated for this IO. */
193 	u64 start_time_ns;
194 	/* Time that I/O was submitted to the device. */
195 	u64 io_start_time_ns;
196 
197 #ifdef CONFIG_BLK_WBT
198 	unsigned short wbt_flags;
199 #endif
200 	/*
201 	 * rq sectors used for blk stats. It has the same value
202 	 * with blk_rq_sectors(rq), except that it never be zeroed
203 	 * by completion.
204 	 */
205 	unsigned short stats_sectors;
206 
207 	/*
208 	 * Number of scatter-gather DMA addr+len pairs after
209 	 * physical address coalescing is performed.
210 	 */
211 	unsigned short nr_phys_segments;
212 
213 #if defined(CONFIG_BLK_DEV_INTEGRITY)
214 	unsigned short nr_integrity_segments;
215 #endif
216 
217 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
218 	struct bio_crypt_ctx *crypt_ctx;
219 	struct blk_ksm_keyslot *crypt_keyslot;
220 #endif
221 
222 	unsigned short write_hint;
223 	unsigned short ioprio;
224 
225 	enum mq_rq_state state;
226 	refcount_t ref;
227 
228 	unsigned int timeout;
229 	unsigned long deadline;
230 
231 	union {
232 		struct __call_single_data csd;
233 		u64 fifo_time;
234 	};
235 
236 	/*
237 	 * completion callback.
238 	 */
239 	rq_end_io_fn *end_io;
240 	void *end_io_data;
241 };
242 
243 static inline bool blk_op_is_scsi(unsigned int op)
244 {
245 	return op == REQ_OP_SCSI_IN || op == REQ_OP_SCSI_OUT;
246 }
247 
248 static inline bool blk_op_is_private(unsigned int op)
249 {
250 	return op == REQ_OP_DRV_IN || op == REQ_OP_DRV_OUT;
251 }
252 
253 static inline bool blk_rq_is_scsi(struct request *rq)
254 {
255 	return blk_op_is_scsi(req_op(rq));
256 }
257 
258 static inline bool blk_rq_is_private(struct request *rq)
259 {
260 	return blk_op_is_private(req_op(rq));
261 }
262 
263 static inline bool blk_rq_is_passthrough(struct request *rq)
264 {
265 	return blk_rq_is_scsi(rq) || blk_rq_is_private(rq);
266 }
267 
268 static inline bool bio_is_passthrough(struct bio *bio)
269 {
270 	unsigned op = bio_op(bio);
271 
272 	return blk_op_is_scsi(op) || blk_op_is_private(op);
273 }
274 
275 static inline bool blk_op_is_passthrough(unsigned int op)
276 {
277 	return (blk_op_is_scsi(op & REQ_OP_MASK) ||
278 			blk_op_is_private(op & REQ_OP_MASK));
279 }
280 
281 static inline unsigned short req_get_ioprio(struct request *req)
282 {
283 	return req->ioprio;
284 }
285 
286 #include <linux/elevator.h>
287 
288 struct blk_queue_ctx;
289 
290 struct bio_vec;
291 
292 enum blk_eh_timer_return {
293 	BLK_EH_DONE,		/* drivers has completed the command */
294 	BLK_EH_RESET_TIMER,	/* reset timer and try again */
295 };
296 
297 enum blk_queue_state {
298 	Queue_down,
299 	Queue_up,
300 };
301 
302 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
303 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
304 
305 #define BLK_SCSI_MAX_CMDS	(256)
306 #define BLK_SCSI_CMD_PER_LONG	(BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
307 
308 /*
309  * Zoned block device models (zoned limit).
310  *
311  * Note: This needs to be ordered from the least to the most severe
312  * restrictions for the inheritance in blk_stack_limits() to work.
313  */
314 enum blk_zoned_model {
315 	BLK_ZONED_NONE = 0,	/* Regular block device */
316 	BLK_ZONED_HA,		/* Host-aware zoned block device */
317 	BLK_ZONED_HM,		/* Host-managed zoned block device */
318 };
319 
320 /*
321  * BLK_BOUNCE_NONE:	never bounce (default)
322  * BLK_BOUNCE_HIGH:	bounce all highmem pages
323  */
324 enum blk_bounce {
325 	BLK_BOUNCE_NONE,
326 	BLK_BOUNCE_HIGH,
327 };
328 
329 struct queue_limits {
330 	enum blk_bounce		bounce;
331 	unsigned long		seg_boundary_mask;
332 	unsigned long		virt_boundary_mask;
333 
334 	unsigned int		max_hw_sectors;
335 	unsigned int		max_dev_sectors;
336 	unsigned int		chunk_sectors;
337 	unsigned int		max_sectors;
338 	unsigned int		max_segment_size;
339 	unsigned int		physical_block_size;
340 	unsigned int		logical_block_size;
341 	unsigned int		alignment_offset;
342 	unsigned int		io_min;
343 	unsigned int		io_opt;
344 	unsigned int		max_discard_sectors;
345 	unsigned int		max_hw_discard_sectors;
346 	unsigned int		max_write_same_sectors;
347 	unsigned int		max_write_zeroes_sectors;
348 	unsigned int		max_zone_append_sectors;
349 	unsigned int		discard_granularity;
350 	unsigned int		discard_alignment;
351 	unsigned int		zone_write_granularity;
352 
353 	unsigned short		max_segments;
354 	unsigned short		max_integrity_segments;
355 	unsigned short		max_discard_segments;
356 
357 	unsigned char		misaligned;
358 	unsigned char		discard_misaligned;
359 	unsigned char		raid_partial_stripes_expensive;
360 	enum blk_zoned_model	zoned;
361 };
362 
363 typedef int (*report_zones_cb)(struct blk_zone *zone, unsigned int idx,
364 			       void *data);
365 
366 void blk_queue_set_zoned(struct gendisk *disk, enum blk_zoned_model model);
367 
368 #ifdef CONFIG_BLK_DEV_ZONED
369 
370 #define BLK_ALL_ZONES  ((unsigned int)-1)
371 int blkdev_report_zones(struct block_device *bdev, sector_t sector,
372 			unsigned int nr_zones, report_zones_cb cb, void *data);
373 unsigned int blkdev_nr_zones(struct gendisk *disk);
374 extern int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
375 			    sector_t sectors, sector_t nr_sectors,
376 			    gfp_t gfp_mask);
377 int blk_revalidate_disk_zones(struct gendisk *disk,
378 			      void (*update_driver_data)(struct gendisk *disk));
379 
380 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
381 				     unsigned int cmd, unsigned long arg);
382 extern int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
383 				  unsigned int cmd, unsigned long arg);
384 
385 #else /* CONFIG_BLK_DEV_ZONED */
386 
387 static inline unsigned int blkdev_nr_zones(struct gendisk *disk)
388 {
389 	return 0;
390 }
391 
392 static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
393 					    fmode_t mode, unsigned int cmd,
394 					    unsigned long arg)
395 {
396 	return -ENOTTY;
397 }
398 
399 static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
400 					 fmode_t mode, unsigned int cmd,
401 					 unsigned long arg)
402 {
403 	return -ENOTTY;
404 }
405 
406 #endif /* CONFIG_BLK_DEV_ZONED */
407 
408 struct request_queue {
409 	struct request		*last_merge;
410 	struct elevator_queue	*elevator;
411 
412 	struct percpu_ref	q_usage_counter;
413 
414 	struct blk_queue_stats	*stats;
415 	struct rq_qos		*rq_qos;
416 
417 	const struct blk_mq_ops	*mq_ops;
418 
419 	/* sw queues */
420 	struct blk_mq_ctx __percpu	*queue_ctx;
421 
422 	unsigned int		queue_depth;
423 
424 	/* hw dispatch queues */
425 	struct blk_mq_hw_ctx	**queue_hw_ctx;
426 	unsigned int		nr_hw_queues;
427 
428 	struct backing_dev_info	*backing_dev_info;
429 
430 	/*
431 	 * The queue owner gets to use this for whatever they like.
432 	 * ll_rw_blk doesn't touch it.
433 	 */
434 	void			*queuedata;
435 
436 	/*
437 	 * various queue flags, see QUEUE_* below
438 	 */
439 	unsigned long		queue_flags;
440 	/*
441 	 * Number of contexts that have called blk_set_pm_only(). If this
442 	 * counter is above zero then only RQF_PM requests are processed.
443 	 */
444 	atomic_t		pm_only;
445 
446 	/*
447 	 * ida allocated id for this queue.  Used to index queues from
448 	 * ioctx.
449 	 */
450 	int			id;
451 
452 	spinlock_t		queue_lock;
453 
454 	/*
455 	 * queue kobject
456 	 */
457 	struct kobject kobj;
458 
459 	/*
460 	 * mq queue kobject
461 	 */
462 	struct kobject *mq_kobj;
463 
464 #ifdef  CONFIG_BLK_DEV_INTEGRITY
465 	struct blk_integrity integrity;
466 #endif	/* CONFIG_BLK_DEV_INTEGRITY */
467 
468 #ifdef CONFIG_PM
469 	struct device		*dev;
470 	enum rpm_status		rpm_status;
471 #endif
472 
473 	/*
474 	 * queue settings
475 	 */
476 	unsigned long		nr_requests;	/* Max # of requests */
477 
478 	unsigned int		dma_pad_mask;
479 	unsigned int		dma_alignment;
480 
481 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
482 	/* Inline crypto capabilities */
483 	struct blk_keyslot_manager *ksm;
484 #endif
485 
486 	unsigned int		rq_timeout;
487 	int			poll_nsec;
488 
489 	struct blk_stat_callback	*poll_cb;
490 	struct blk_rq_stat	poll_stat[BLK_MQ_POLL_STATS_BKTS];
491 
492 	struct timer_list	timeout;
493 	struct work_struct	timeout_work;
494 
495 	atomic_t		nr_active_requests_shared_sbitmap;
496 
497 	struct list_head	icq_list;
498 #ifdef CONFIG_BLK_CGROUP
499 	DECLARE_BITMAP		(blkcg_pols, BLKCG_MAX_POLS);
500 	struct blkcg_gq		*root_blkg;
501 	struct list_head	blkg_list;
502 #endif
503 
504 	struct queue_limits	limits;
505 
506 	unsigned int		required_elevator_features;
507 
508 #ifdef CONFIG_BLK_DEV_ZONED
509 	/*
510 	 * Zoned block device information for request dispatch control.
511 	 * nr_zones is the total number of zones of the device. This is always
512 	 * 0 for regular block devices. conv_zones_bitmap is a bitmap of nr_zones
513 	 * bits which indicates if a zone is conventional (bit set) or
514 	 * sequential (bit clear). seq_zones_wlock is a bitmap of nr_zones
515 	 * bits which indicates if a zone is write locked, that is, if a write
516 	 * request targeting the zone was dispatched. All three fields are
517 	 * initialized by the low level device driver (e.g. scsi/sd.c).
518 	 * Stacking drivers (device mappers) may or may not initialize
519 	 * these fields.
520 	 *
521 	 * Reads of this information must be protected with blk_queue_enter() /
522 	 * blk_queue_exit(). Modifying this information is only allowed while
523 	 * no requests are being processed. See also blk_mq_freeze_queue() and
524 	 * blk_mq_unfreeze_queue().
525 	 */
526 	unsigned int		nr_zones;
527 	unsigned long		*conv_zones_bitmap;
528 	unsigned long		*seq_zones_wlock;
529 	unsigned int		max_open_zones;
530 	unsigned int		max_active_zones;
531 #endif /* CONFIG_BLK_DEV_ZONED */
532 
533 	/*
534 	 * sg stuff
535 	 */
536 	unsigned int		sg_timeout;
537 	unsigned int		sg_reserved_size;
538 	int			node;
539 	struct mutex		debugfs_mutex;
540 #ifdef CONFIG_BLK_DEV_IO_TRACE
541 	struct blk_trace __rcu	*blk_trace;
542 #endif
543 	/*
544 	 * for flush operations
545 	 */
546 	struct blk_flush_queue	*fq;
547 
548 	struct list_head	requeue_list;
549 	spinlock_t		requeue_lock;
550 	struct delayed_work	requeue_work;
551 
552 	struct mutex		sysfs_lock;
553 	struct mutex		sysfs_dir_lock;
554 
555 	/*
556 	 * for reusing dead hctx instance in case of updating
557 	 * nr_hw_queues
558 	 */
559 	struct list_head	unused_hctx_list;
560 	spinlock_t		unused_hctx_lock;
561 
562 	int			mq_freeze_depth;
563 
564 #if defined(CONFIG_BLK_DEV_BSG)
565 	struct bsg_class_device bsg_dev;
566 #endif
567 
568 #ifdef CONFIG_BLK_DEV_THROTTLING
569 	/* Throttle data */
570 	struct throtl_data *td;
571 #endif
572 	struct rcu_head		rcu_head;
573 	wait_queue_head_t	mq_freeze_wq;
574 	/*
575 	 * Protect concurrent access to q_usage_counter by
576 	 * percpu_ref_kill() and percpu_ref_reinit().
577 	 */
578 	struct mutex		mq_freeze_lock;
579 
580 	struct blk_mq_tag_set	*tag_set;
581 	struct list_head	tag_set_list;
582 	struct bio_set		bio_split;
583 
584 	struct dentry		*debugfs_dir;
585 
586 #ifdef CONFIG_BLK_DEBUG_FS
587 	struct dentry		*sched_debugfs_dir;
588 	struct dentry		*rqos_debugfs_dir;
589 #endif
590 
591 	bool			mq_sysfs_init_done;
592 
593 	size_t			cmd_size;
594 
595 #define BLK_MAX_WRITE_HINTS	5
596 	u64			write_hints[BLK_MAX_WRITE_HINTS];
597 };
598 
599 /* Keep blk_queue_flag_name[] in sync with the definitions below */
600 #define QUEUE_FLAG_STOPPED	0	/* queue is stopped */
601 #define QUEUE_FLAG_DYING	1	/* queue being torn down */
602 #define QUEUE_FLAG_NOMERGES     3	/* disable merge attempts */
603 #define QUEUE_FLAG_SAME_COMP	4	/* complete on same CPU-group */
604 #define QUEUE_FLAG_FAIL_IO	5	/* fake timeout */
605 #define QUEUE_FLAG_NONROT	6	/* non-rotational device (SSD) */
606 #define QUEUE_FLAG_VIRT		QUEUE_FLAG_NONROT /* paravirt device */
607 #define QUEUE_FLAG_IO_STAT	7	/* do disk/partitions IO accounting */
608 #define QUEUE_FLAG_DISCARD	8	/* supports DISCARD */
609 #define QUEUE_FLAG_NOXMERGES	9	/* No extended merges */
610 #define QUEUE_FLAG_ADD_RANDOM	10	/* Contributes to random pool */
611 #define QUEUE_FLAG_SECERASE	11	/* supports secure erase */
612 #define QUEUE_FLAG_SAME_FORCE	12	/* force complete on same CPU */
613 #define QUEUE_FLAG_DEAD		13	/* queue tear-down finished */
614 #define QUEUE_FLAG_INIT_DONE	14	/* queue is initialized */
615 #define QUEUE_FLAG_STABLE_WRITES 15	/* don't modify blks until WB is done */
616 #define QUEUE_FLAG_POLL		16	/* IO polling enabled if set */
617 #define QUEUE_FLAG_WC		17	/* Write back caching */
618 #define QUEUE_FLAG_FUA		18	/* device supports FUA writes */
619 #define QUEUE_FLAG_DAX		19	/* device supports DAX */
620 #define QUEUE_FLAG_STATS	20	/* track IO start and completion times */
621 #define QUEUE_FLAG_POLL_STATS	21	/* collecting stats for hybrid polling */
622 #define QUEUE_FLAG_REGISTERED	22	/* queue has been registered to a disk */
623 #define QUEUE_FLAG_SCSI_PASSTHROUGH 23	/* queue supports SCSI commands */
624 #define QUEUE_FLAG_QUIESCED	24	/* queue has been quiesced */
625 #define QUEUE_FLAG_PCI_P2PDMA	25	/* device supports PCI p2p requests */
626 #define QUEUE_FLAG_ZONE_RESETALL 26	/* supports Zone Reset All */
627 #define QUEUE_FLAG_RQ_ALLOC_TIME 27	/* record rq->alloc_time_ns */
628 #define QUEUE_FLAG_HCTX_ACTIVE	28	/* at least one blk-mq hctx is active */
629 #define QUEUE_FLAG_NOWAIT       29	/* device supports NOWAIT */
630 
631 #define QUEUE_FLAG_MQ_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
632 				 (1 << QUEUE_FLAG_SAME_COMP) |		\
633 				 (1 << QUEUE_FLAG_NOWAIT))
634 
635 void blk_queue_flag_set(unsigned int flag, struct request_queue *q);
636 void blk_queue_flag_clear(unsigned int flag, struct request_queue *q);
637 bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);
638 
639 #define blk_queue_stopped(q)	test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
640 #define blk_queue_dying(q)	test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
641 #define blk_queue_dead(q)	test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
642 #define blk_queue_init_done(q)	test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
643 #define blk_queue_nomerges(q)	test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
644 #define blk_queue_noxmerges(q)	\
645 	test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
646 #define blk_queue_nonrot(q)	test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
647 #define blk_queue_stable_writes(q) \
648 	test_bit(QUEUE_FLAG_STABLE_WRITES, &(q)->queue_flags)
649 #define blk_queue_io_stat(q)	test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
650 #define blk_queue_add_random(q)	test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
651 #define blk_queue_discard(q)	test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
652 #define blk_queue_zone_resetall(q)	\
653 	test_bit(QUEUE_FLAG_ZONE_RESETALL, &(q)->queue_flags)
654 #define blk_queue_secure_erase(q) \
655 	(test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
656 #define blk_queue_dax(q)	test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
657 #define blk_queue_scsi_passthrough(q)	\
658 	test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags)
659 #define blk_queue_pci_p2pdma(q)	\
660 	test_bit(QUEUE_FLAG_PCI_P2PDMA, &(q)->queue_flags)
661 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
662 #define blk_queue_rq_alloc_time(q)	\
663 	test_bit(QUEUE_FLAG_RQ_ALLOC_TIME, &(q)->queue_flags)
664 #else
665 #define blk_queue_rq_alloc_time(q)	false
666 #endif
667 
668 #define blk_noretry_request(rq) \
669 	((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
670 			     REQ_FAILFAST_DRIVER))
671 #define blk_queue_quiesced(q)	test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
672 #define blk_queue_pm_only(q)	atomic_read(&(q)->pm_only)
673 #define blk_queue_fua(q)	test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags)
674 #define blk_queue_registered(q)	test_bit(QUEUE_FLAG_REGISTERED, &(q)->queue_flags)
675 #define blk_queue_nowait(q)	test_bit(QUEUE_FLAG_NOWAIT, &(q)->queue_flags)
676 
677 extern void blk_set_pm_only(struct request_queue *q);
678 extern void blk_clear_pm_only(struct request_queue *q);
679 
680 static inline bool blk_account_rq(struct request *rq)
681 {
682 	return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq);
683 }
684 
685 #define list_entry_rq(ptr)	list_entry((ptr), struct request, queuelist)
686 
687 #define rq_data_dir(rq)		(op_is_write(req_op(rq)) ? WRITE : READ)
688 
689 #define rq_dma_dir(rq) \
690 	(op_is_write(req_op(rq)) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
691 
692 #define dma_map_bvec(dev, bv, dir, attrs) \
693 	dma_map_page_attrs(dev, (bv)->bv_page, (bv)->bv_offset, (bv)->bv_len, \
694 	(dir), (attrs))
695 
696 #define queue_to_disk(q)	(dev_to_disk(kobj_to_dev((q)->kobj.parent)))
697 
698 static inline bool queue_is_mq(struct request_queue *q)
699 {
700 	return q->mq_ops;
701 }
702 
703 #ifdef CONFIG_PM
704 static inline enum rpm_status queue_rpm_status(struct request_queue *q)
705 {
706 	return q->rpm_status;
707 }
708 #else
709 static inline enum rpm_status queue_rpm_status(struct request_queue *q)
710 {
711 	return RPM_ACTIVE;
712 }
713 #endif
714 
715 static inline enum blk_zoned_model
716 blk_queue_zoned_model(struct request_queue *q)
717 {
718 	if (IS_ENABLED(CONFIG_BLK_DEV_ZONED))
719 		return q->limits.zoned;
720 	return BLK_ZONED_NONE;
721 }
722 
723 static inline bool blk_queue_is_zoned(struct request_queue *q)
724 {
725 	switch (blk_queue_zoned_model(q)) {
726 	case BLK_ZONED_HA:
727 	case BLK_ZONED_HM:
728 		return true;
729 	default:
730 		return false;
731 	}
732 }
733 
734 static inline sector_t blk_queue_zone_sectors(struct request_queue *q)
735 {
736 	return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0;
737 }
738 
739 #ifdef CONFIG_BLK_DEV_ZONED
740 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
741 {
742 	return blk_queue_is_zoned(q) ? q->nr_zones : 0;
743 }
744 
745 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
746 					     sector_t sector)
747 {
748 	if (!blk_queue_is_zoned(q))
749 		return 0;
750 	return sector >> ilog2(q->limits.chunk_sectors);
751 }
752 
753 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
754 					 sector_t sector)
755 {
756 	if (!blk_queue_is_zoned(q))
757 		return false;
758 	if (!q->conv_zones_bitmap)
759 		return true;
760 	return !test_bit(blk_queue_zone_no(q, sector), q->conv_zones_bitmap);
761 }
762 
763 static inline void blk_queue_max_open_zones(struct request_queue *q,
764 		unsigned int max_open_zones)
765 {
766 	q->max_open_zones = max_open_zones;
767 }
768 
769 static inline unsigned int queue_max_open_zones(const struct request_queue *q)
770 {
771 	return q->max_open_zones;
772 }
773 
774 static inline void blk_queue_max_active_zones(struct request_queue *q,
775 		unsigned int max_active_zones)
776 {
777 	q->max_active_zones = max_active_zones;
778 }
779 
780 static inline unsigned int queue_max_active_zones(const struct request_queue *q)
781 {
782 	return q->max_active_zones;
783 }
784 #else /* CONFIG_BLK_DEV_ZONED */
785 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
786 {
787 	return 0;
788 }
789 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
790 					 sector_t sector)
791 {
792 	return false;
793 }
794 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
795 					     sector_t sector)
796 {
797 	return 0;
798 }
799 static inline unsigned int queue_max_open_zones(const struct request_queue *q)
800 {
801 	return 0;
802 }
803 static inline unsigned int queue_max_active_zones(const struct request_queue *q)
804 {
805 	return 0;
806 }
807 #endif /* CONFIG_BLK_DEV_ZONED */
808 
809 static inline bool rq_is_sync(struct request *rq)
810 {
811 	return op_is_sync(rq->cmd_flags);
812 }
813 
814 static inline bool rq_mergeable(struct request *rq)
815 {
816 	if (blk_rq_is_passthrough(rq))
817 		return false;
818 
819 	if (req_op(rq) == REQ_OP_FLUSH)
820 		return false;
821 
822 	if (req_op(rq) == REQ_OP_WRITE_ZEROES)
823 		return false;
824 
825 	if (req_op(rq) == REQ_OP_ZONE_APPEND)
826 		return false;
827 
828 	if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
829 		return false;
830 	if (rq->rq_flags & RQF_NOMERGE_FLAGS)
831 		return false;
832 
833 	return true;
834 }
835 
836 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
837 {
838 	if (bio_page(a) == bio_page(b) &&
839 	    bio_offset(a) == bio_offset(b))
840 		return true;
841 
842 	return false;
843 }
844 
845 static inline unsigned int blk_queue_depth(struct request_queue *q)
846 {
847 	if (q->queue_depth)
848 		return q->queue_depth;
849 
850 	return q->nr_requests;
851 }
852 
853 /*
854  * default timeout for SG_IO if none specified
855  */
856 #define BLK_DEFAULT_SG_TIMEOUT	(60 * HZ)
857 #define BLK_MIN_SG_TIMEOUT	(7 * HZ)
858 
859 struct rq_map_data {
860 	struct page **pages;
861 	int page_order;
862 	int nr_entries;
863 	unsigned long offset;
864 	int null_mapped;
865 	int from_user;
866 };
867 
868 struct req_iterator {
869 	struct bvec_iter iter;
870 	struct bio *bio;
871 };
872 
873 /* This should not be used directly - use rq_for_each_segment */
874 #define for_each_bio(_bio)		\
875 	for (; _bio; _bio = _bio->bi_next)
876 #define __rq_for_each_bio(_bio, rq)	\
877 	if ((rq->bio))			\
878 		for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
879 
880 #define rq_for_each_segment(bvl, _rq, _iter)			\
881 	__rq_for_each_bio(_iter.bio, _rq)			\
882 		bio_for_each_segment(bvl, _iter.bio, _iter.iter)
883 
884 #define rq_for_each_bvec(bvl, _rq, _iter)			\
885 	__rq_for_each_bio(_iter.bio, _rq)			\
886 		bio_for_each_bvec(bvl, _iter.bio, _iter.iter)
887 
888 #define rq_iter_last(bvec, _iter)				\
889 		(_iter.bio->bi_next == NULL &&			\
890 		 bio_iter_last(bvec, _iter.iter))
891 
892 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
893 # error	"You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
894 #endif
895 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
896 extern void rq_flush_dcache_pages(struct request *rq);
897 #else
898 static inline void rq_flush_dcache_pages(struct request *rq)
899 {
900 }
901 #endif
902 
903 extern int blk_register_queue(struct gendisk *disk);
904 extern void blk_unregister_queue(struct gendisk *disk);
905 blk_qc_t submit_bio_noacct(struct bio *bio);
906 extern void blk_rq_init(struct request_queue *q, struct request *rq);
907 extern void blk_put_request(struct request *);
908 extern struct request *blk_get_request(struct request_queue *, unsigned int op,
909 				       blk_mq_req_flags_t flags);
910 extern int blk_lld_busy(struct request_queue *q);
911 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
912 			     struct bio_set *bs, gfp_t gfp_mask,
913 			     int (*bio_ctr)(struct bio *, struct bio *, void *),
914 			     void *data);
915 extern void blk_rq_unprep_clone(struct request *rq);
916 extern blk_status_t blk_insert_cloned_request(struct request_queue *q,
917 				     struct request *rq);
918 int blk_rq_append_bio(struct request *rq, struct bio *bio);
919 extern void blk_queue_split(struct bio **);
920 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
921 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
922 			      unsigned int, void __user *);
923 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
924 			  unsigned int, void __user *);
925 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
926 			 struct scsi_ioctl_command __user *);
927 extern int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp);
928 extern int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp);
929 
930 extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
931 extern void blk_queue_exit(struct request_queue *q);
932 extern void blk_sync_queue(struct request_queue *q);
933 extern int blk_rq_map_user(struct request_queue *, struct request *,
934 			   struct rq_map_data *, void __user *, unsigned long,
935 			   gfp_t);
936 extern int blk_rq_unmap_user(struct bio *);
937 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
938 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
939 			       struct rq_map_data *, const struct iov_iter *,
940 			       gfp_t);
941 extern void blk_execute_rq(struct gendisk *, struct request *, int);
942 extern void blk_execute_rq_nowait(struct gendisk *,
943 				  struct request *, int, rq_end_io_fn *);
944 
945 /* Helper to convert REQ_OP_XXX to its string format XXX */
946 extern const char *blk_op_str(unsigned int op);
947 
948 int blk_status_to_errno(blk_status_t status);
949 blk_status_t errno_to_blk_status(int errno);
950 
951 int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin);
952 
953 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
954 {
955 	return bdev->bd_disk->queue;	/* this is never NULL */
956 }
957 
958 /*
959  * The basic unit of block I/O is a sector. It is used in a number of contexts
960  * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
961  * bytes. Variables of type sector_t represent an offset or size that is a
962  * multiple of 512 bytes. Hence these two constants.
963  */
964 #ifndef SECTOR_SHIFT
965 #define SECTOR_SHIFT 9
966 #endif
967 #ifndef SECTOR_SIZE
968 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
969 #endif
970 
971 /*
972  * blk_rq_pos()			: the current sector
973  * blk_rq_bytes()		: bytes left in the entire request
974  * blk_rq_cur_bytes()		: bytes left in the current segment
975  * blk_rq_err_bytes()		: bytes left till the next error boundary
976  * blk_rq_sectors()		: sectors left in the entire request
977  * blk_rq_cur_sectors()		: sectors left in the current segment
978  * blk_rq_stats_sectors()	: sectors of the entire request used for stats
979  */
980 static inline sector_t blk_rq_pos(const struct request *rq)
981 {
982 	return rq->__sector;
983 }
984 
985 static inline unsigned int blk_rq_bytes(const struct request *rq)
986 {
987 	return rq->__data_len;
988 }
989 
990 static inline int blk_rq_cur_bytes(const struct request *rq)
991 {
992 	return rq->bio ? bio_cur_bytes(rq->bio) : 0;
993 }
994 
995 extern unsigned int blk_rq_err_bytes(const struct request *rq);
996 
997 static inline unsigned int blk_rq_sectors(const struct request *rq)
998 {
999 	return blk_rq_bytes(rq) >> SECTOR_SHIFT;
1000 }
1001 
1002 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
1003 {
1004 	return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
1005 }
1006 
1007 static inline unsigned int blk_rq_stats_sectors(const struct request *rq)
1008 {
1009 	return rq->stats_sectors;
1010 }
1011 
1012 #ifdef CONFIG_BLK_DEV_ZONED
1013 
1014 /* Helper to convert BLK_ZONE_ZONE_XXX to its string format XXX */
1015 const char *blk_zone_cond_str(enum blk_zone_cond zone_cond);
1016 
1017 static inline unsigned int blk_rq_zone_no(struct request *rq)
1018 {
1019 	return blk_queue_zone_no(rq->q, blk_rq_pos(rq));
1020 }
1021 
1022 static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
1023 {
1024 	return blk_queue_zone_is_seq(rq->q, blk_rq_pos(rq));
1025 }
1026 #endif /* CONFIG_BLK_DEV_ZONED */
1027 
1028 /*
1029  * Some commands like WRITE SAME have a payload or data transfer size which
1030  * is different from the size of the request.  Any driver that supports such
1031  * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
1032  * calculate the data transfer size.
1033  */
1034 static inline unsigned int blk_rq_payload_bytes(struct request *rq)
1035 {
1036 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1037 		return rq->special_vec.bv_len;
1038 	return blk_rq_bytes(rq);
1039 }
1040 
1041 /*
1042  * Return the first full biovec in the request.  The caller needs to check that
1043  * there are any bvecs before calling this helper.
1044  */
1045 static inline struct bio_vec req_bvec(struct request *rq)
1046 {
1047 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1048 		return rq->special_vec;
1049 	return mp_bvec_iter_bvec(rq->bio->bi_io_vec, rq->bio->bi_iter);
1050 }
1051 
1052 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
1053 						     int op)
1054 {
1055 	if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
1056 		return min(q->limits.max_discard_sectors,
1057 			   UINT_MAX >> SECTOR_SHIFT);
1058 
1059 	if (unlikely(op == REQ_OP_WRITE_SAME))
1060 		return q->limits.max_write_same_sectors;
1061 
1062 	if (unlikely(op == REQ_OP_WRITE_ZEROES))
1063 		return q->limits.max_write_zeroes_sectors;
1064 
1065 	return q->limits.max_sectors;
1066 }
1067 
1068 /*
1069  * Return maximum size of a request at given offset. Only valid for
1070  * file system requests.
1071  */
1072 static inline unsigned int blk_max_size_offset(struct request_queue *q,
1073 					       sector_t offset,
1074 					       unsigned int chunk_sectors)
1075 {
1076 	if (!chunk_sectors) {
1077 		if (q->limits.chunk_sectors)
1078 			chunk_sectors = q->limits.chunk_sectors;
1079 		else
1080 			return q->limits.max_sectors;
1081 	}
1082 
1083 	if (likely(is_power_of_2(chunk_sectors)))
1084 		chunk_sectors -= offset & (chunk_sectors - 1);
1085 	else
1086 		chunk_sectors -= sector_div(offset, chunk_sectors);
1087 
1088 	return min(q->limits.max_sectors, chunk_sectors);
1089 }
1090 
1091 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
1092 						  sector_t offset)
1093 {
1094 	struct request_queue *q = rq->q;
1095 
1096 	if (blk_rq_is_passthrough(rq))
1097 		return q->limits.max_hw_sectors;
1098 
1099 	if (!q->limits.chunk_sectors ||
1100 	    req_op(rq) == REQ_OP_DISCARD ||
1101 	    req_op(rq) == REQ_OP_SECURE_ERASE)
1102 		return blk_queue_get_max_sectors(q, req_op(rq));
1103 
1104 	return min(blk_max_size_offset(q, offset, 0),
1105 			blk_queue_get_max_sectors(q, req_op(rq)));
1106 }
1107 
1108 static inline unsigned int blk_rq_count_bios(struct request *rq)
1109 {
1110 	unsigned int nr_bios = 0;
1111 	struct bio *bio;
1112 
1113 	__rq_for_each_bio(bio, rq)
1114 		nr_bios++;
1115 
1116 	return nr_bios;
1117 }
1118 
1119 void blk_steal_bios(struct bio_list *list, struct request *rq);
1120 
1121 /*
1122  * Request completion related functions.
1123  *
1124  * blk_update_request() completes given number of bytes and updates
1125  * the request without completing it.
1126  */
1127 extern bool blk_update_request(struct request *rq, blk_status_t error,
1128 			       unsigned int nr_bytes);
1129 
1130 extern void blk_abort_request(struct request *);
1131 
1132 /*
1133  * Access functions for manipulating queue properties
1134  */
1135 extern void blk_cleanup_queue(struct request_queue *);
1136 void blk_queue_bounce_limit(struct request_queue *q, enum blk_bounce limit);
1137 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1138 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1139 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1140 extern void blk_queue_max_discard_segments(struct request_queue *,
1141 		unsigned short);
1142 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1143 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1144 		unsigned int max_discard_sectors);
1145 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1146 		unsigned int max_write_same_sectors);
1147 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
1148 		unsigned int max_write_same_sectors);
1149 extern void blk_queue_logical_block_size(struct request_queue *, unsigned int);
1150 extern void blk_queue_max_zone_append_sectors(struct request_queue *q,
1151 		unsigned int max_zone_append_sectors);
1152 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1153 void blk_queue_zone_write_granularity(struct request_queue *q,
1154 				      unsigned int size);
1155 extern void blk_queue_alignment_offset(struct request_queue *q,
1156 				       unsigned int alignment);
1157 void blk_queue_update_readahead(struct request_queue *q);
1158 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1159 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1160 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1161 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1162 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth);
1163 extern void blk_set_default_limits(struct queue_limits *lim);
1164 extern void blk_set_stacking_limits(struct queue_limits *lim);
1165 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1166 			    sector_t offset);
1167 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1168 			      sector_t offset);
1169 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1170 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1171 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1172 extern void blk_queue_dma_alignment(struct request_queue *, int);
1173 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1174 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1175 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1176 extern void blk_queue_required_elevator_features(struct request_queue *q,
1177 						 unsigned int features);
1178 extern bool blk_queue_can_use_dma_map_merging(struct request_queue *q,
1179 					      struct device *dev);
1180 
1181 /*
1182  * Number of physical segments as sent to the device.
1183  *
1184  * Normally this is the number of discontiguous data segments sent by the
1185  * submitter.  But for data-less command like discard we might have no
1186  * actual data segments submitted, but the driver might have to add it's
1187  * own special payload.  In that case we still return 1 here so that this
1188  * special payload will be mapped.
1189  */
1190 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
1191 {
1192 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1193 		return 1;
1194 	return rq->nr_phys_segments;
1195 }
1196 
1197 /*
1198  * Number of discard segments (or ranges) the driver needs to fill in.
1199  * Each discard bio merged into a request is counted as one segment.
1200  */
1201 static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
1202 {
1203 	return max_t(unsigned short, rq->nr_phys_segments, 1);
1204 }
1205 
1206 int __blk_rq_map_sg(struct request_queue *q, struct request *rq,
1207 		struct scatterlist *sglist, struct scatterlist **last_sg);
1208 static inline int blk_rq_map_sg(struct request_queue *q, struct request *rq,
1209 		struct scatterlist *sglist)
1210 {
1211 	struct scatterlist *last_sg = NULL;
1212 
1213 	return __blk_rq_map_sg(q, rq, sglist, &last_sg);
1214 }
1215 extern void blk_dump_rq_flags(struct request *, char *);
1216 
1217 bool __must_check blk_get_queue(struct request_queue *);
1218 struct request_queue *blk_alloc_queue(int node_id);
1219 extern void blk_put_queue(struct request_queue *);
1220 extern void blk_set_queue_dying(struct request_queue *);
1221 
1222 #ifdef CONFIG_BLOCK
1223 /*
1224  * blk_plug permits building a queue of related requests by holding the I/O
1225  * fragments for a short period. This allows merging of sequential requests
1226  * into single larger request. As the requests are moved from a per-task list to
1227  * the device's request_queue in a batch, this results in improved scalability
1228  * as the lock contention for request_queue lock is reduced.
1229  *
1230  * It is ok not to disable preemption when adding the request to the plug list
1231  * or when attempting a merge, because blk_schedule_flush_list() will only flush
1232  * the plug list when the task sleeps by itself. For details, please see
1233  * schedule() where blk_schedule_flush_plug() is called.
1234  */
1235 struct blk_plug {
1236 	struct list_head mq_list; /* blk-mq requests */
1237 	struct list_head cb_list; /* md requires an unplug callback */
1238 	unsigned short rq_count;
1239 	bool multiple_queues;
1240 	bool nowait;
1241 };
1242 #define BLK_MAX_REQUEST_COUNT 16
1243 #define BLK_PLUG_FLUSH_SIZE (128 * 1024)
1244 
1245 struct blk_plug_cb;
1246 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1247 struct blk_plug_cb {
1248 	struct list_head list;
1249 	blk_plug_cb_fn callback;
1250 	void *data;
1251 };
1252 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1253 					     void *data, int size);
1254 extern void blk_start_plug(struct blk_plug *);
1255 extern void blk_finish_plug(struct blk_plug *);
1256 extern void blk_flush_plug_list(struct blk_plug *, bool);
1257 
1258 static inline void blk_flush_plug(struct task_struct *tsk)
1259 {
1260 	struct blk_plug *plug = tsk->plug;
1261 
1262 	if (plug)
1263 		blk_flush_plug_list(plug, false);
1264 }
1265 
1266 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1267 {
1268 	struct blk_plug *plug = tsk->plug;
1269 
1270 	if (plug)
1271 		blk_flush_plug_list(plug, true);
1272 }
1273 
1274 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1275 {
1276 	struct blk_plug *plug = tsk->plug;
1277 
1278 	return plug &&
1279 		 (!list_empty(&plug->mq_list) ||
1280 		 !list_empty(&plug->cb_list));
1281 }
1282 
1283 int blkdev_issue_flush(struct block_device *bdev);
1284 long nr_blockdev_pages(void);
1285 #else /* CONFIG_BLOCK */
1286 struct blk_plug {
1287 };
1288 
1289 static inline void blk_start_plug(struct blk_plug *plug)
1290 {
1291 }
1292 
1293 static inline void blk_finish_plug(struct blk_plug *plug)
1294 {
1295 }
1296 
1297 static inline void blk_flush_plug(struct task_struct *task)
1298 {
1299 }
1300 
1301 static inline void blk_schedule_flush_plug(struct task_struct *task)
1302 {
1303 }
1304 
1305 
1306 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1307 {
1308 	return false;
1309 }
1310 
1311 static inline int blkdev_issue_flush(struct block_device *bdev)
1312 {
1313 	return 0;
1314 }
1315 
1316 static inline long nr_blockdev_pages(void)
1317 {
1318 	return 0;
1319 }
1320 #endif /* CONFIG_BLOCK */
1321 
1322 extern void blk_io_schedule(void);
1323 
1324 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1325 		sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1326 
1327 #define BLKDEV_DISCARD_SECURE	(1 << 0)	/* issue a secure erase */
1328 
1329 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1330 		sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1331 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1332 		sector_t nr_sects, gfp_t gfp_mask, int flags,
1333 		struct bio **biop);
1334 
1335 #define BLKDEV_ZERO_NOUNMAP	(1 << 0)  /* do not free blocks */
1336 #define BLKDEV_ZERO_NOFALLBACK	(1 << 1)  /* don't write explicit zeroes */
1337 
1338 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1339 		sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
1340 		unsigned flags);
1341 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1342 		sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
1343 
1344 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1345 		sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1346 {
1347 	return blkdev_issue_discard(sb->s_bdev,
1348 				    block << (sb->s_blocksize_bits -
1349 					      SECTOR_SHIFT),
1350 				    nr_blocks << (sb->s_blocksize_bits -
1351 						  SECTOR_SHIFT),
1352 				    gfp_mask, flags);
1353 }
1354 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1355 		sector_t nr_blocks, gfp_t gfp_mask)
1356 {
1357 	return blkdev_issue_zeroout(sb->s_bdev,
1358 				    block << (sb->s_blocksize_bits -
1359 					      SECTOR_SHIFT),
1360 				    nr_blocks << (sb->s_blocksize_bits -
1361 						  SECTOR_SHIFT),
1362 				    gfp_mask, 0);
1363 }
1364 
1365 extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
1366 
1367 static inline bool bdev_is_partition(struct block_device *bdev)
1368 {
1369 	return bdev->bd_partno;
1370 }
1371 
1372 enum blk_default_limits {
1373 	BLK_MAX_SEGMENTS	= 128,
1374 	BLK_SAFE_MAX_SECTORS	= 255,
1375 	BLK_DEF_MAX_SECTORS	= 2560,
1376 	BLK_MAX_SEGMENT_SIZE	= 65536,
1377 	BLK_SEG_BOUNDARY_MASK	= 0xFFFFFFFFUL,
1378 };
1379 
1380 static inline unsigned long queue_segment_boundary(const struct request_queue *q)
1381 {
1382 	return q->limits.seg_boundary_mask;
1383 }
1384 
1385 static inline unsigned long queue_virt_boundary(const struct request_queue *q)
1386 {
1387 	return q->limits.virt_boundary_mask;
1388 }
1389 
1390 static inline unsigned int queue_max_sectors(const struct request_queue *q)
1391 {
1392 	return q->limits.max_sectors;
1393 }
1394 
1395 static inline unsigned int queue_max_hw_sectors(const struct request_queue *q)
1396 {
1397 	return q->limits.max_hw_sectors;
1398 }
1399 
1400 static inline unsigned short queue_max_segments(const struct request_queue *q)
1401 {
1402 	return q->limits.max_segments;
1403 }
1404 
1405 static inline unsigned short queue_max_discard_segments(const struct request_queue *q)
1406 {
1407 	return q->limits.max_discard_segments;
1408 }
1409 
1410 static inline unsigned int queue_max_segment_size(const struct request_queue *q)
1411 {
1412 	return q->limits.max_segment_size;
1413 }
1414 
1415 static inline unsigned int queue_max_zone_append_sectors(const struct request_queue *q)
1416 {
1417 
1418 	const struct queue_limits *l = &q->limits;
1419 
1420 	return min(l->max_zone_append_sectors, l->max_sectors);
1421 }
1422 
1423 static inline unsigned queue_logical_block_size(const struct request_queue *q)
1424 {
1425 	int retval = 512;
1426 
1427 	if (q && q->limits.logical_block_size)
1428 		retval = q->limits.logical_block_size;
1429 
1430 	return retval;
1431 }
1432 
1433 static inline unsigned int bdev_logical_block_size(struct block_device *bdev)
1434 {
1435 	return queue_logical_block_size(bdev_get_queue(bdev));
1436 }
1437 
1438 static inline unsigned int queue_physical_block_size(const struct request_queue *q)
1439 {
1440 	return q->limits.physical_block_size;
1441 }
1442 
1443 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1444 {
1445 	return queue_physical_block_size(bdev_get_queue(bdev));
1446 }
1447 
1448 static inline unsigned int queue_io_min(const struct request_queue *q)
1449 {
1450 	return q->limits.io_min;
1451 }
1452 
1453 static inline int bdev_io_min(struct block_device *bdev)
1454 {
1455 	return queue_io_min(bdev_get_queue(bdev));
1456 }
1457 
1458 static inline unsigned int queue_io_opt(const struct request_queue *q)
1459 {
1460 	return q->limits.io_opt;
1461 }
1462 
1463 static inline int bdev_io_opt(struct block_device *bdev)
1464 {
1465 	return queue_io_opt(bdev_get_queue(bdev));
1466 }
1467 
1468 static inline unsigned int
1469 queue_zone_write_granularity(const struct request_queue *q)
1470 {
1471 	return q->limits.zone_write_granularity;
1472 }
1473 
1474 static inline unsigned int
1475 bdev_zone_write_granularity(struct block_device *bdev)
1476 {
1477 	return queue_zone_write_granularity(bdev_get_queue(bdev));
1478 }
1479 
1480 static inline int queue_alignment_offset(const struct request_queue *q)
1481 {
1482 	if (q->limits.misaligned)
1483 		return -1;
1484 
1485 	return q->limits.alignment_offset;
1486 }
1487 
1488 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1489 {
1490 	unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1491 	unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1492 		<< SECTOR_SHIFT;
1493 
1494 	return (granularity + lim->alignment_offset - alignment) % granularity;
1495 }
1496 
1497 static inline int bdev_alignment_offset(struct block_device *bdev)
1498 {
1499 	struct request_queue *q = bdev_get_queue(bdev);
1500 
1501 	if (q->limits.misaligned)
1502 		return -1;
1503 	if (bdev_is_partition(bdev))
1504 		return queue_limit_alignment_offset(&q->limits,
1505 				bdev->bd_start_sect);
1506 	return q->limits.alignment_offset;
1507 }
1508 
1509 static inline int queue_discard_alignment(const struct request_queue *q)
1510 {
1511 	if (q->limits.discard_misaligned)
1512 		return -1;
1513 
1514 	return q->limits.discard_alignment;
1515 }
1516 
1517 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1518 {
1519 	unsigned int alignment, granularity, offset;
1520 
1521 	if (!lim->max_discard_sectors)
1522 		return 0;
1523 
1524 	/* Why are these in bytes, not sectors? */
1525 	alignment = lim->discard_alignment >> SECTOR_SHIFT;
1526 	granularity = lim->discard_granularity >> SECTOR_SHIFT;
1527 	if (!granularity)
1528 		return 0;
1529 
1530 	/* Offset of the partition start in 'granularity' sectors */
1531 	offset = sector_div(sector, granularity);
1532 
1533 	/* And why do we do this modulus *again* in blkdev_issue_discard()? */
1534 	offset = (granularity + alignment - offset) % granularity;
1535 
1536 	/* Turn it back into bytes, gaah */
1537 	return offset << SECTOR_SHIFT;
1538 }
1539 
1540 static inline int bdev_discard_alignment(struct block_device *bdev)
1541 {
1542 	struct request_queue *q = bdev_get_queue(bdev);
1543 
1544 	if (bdev_is_partition(bdev))
1545 		return queue_limit_discard_alignment(&q->limits,
1546 				bdev->bd_start_sect);
1547 	return q->limits.discard_alignment;
1548 }
1549 
1550 static inline unsigned int bdev_write_same(struct block_device *bdev)
1551 {
1552 	struct request_queue *q = bdev_get_queue(bdev);
1553 
1554 	if (q)
1555 		return q->limits.max_write_same_sectors;
1556 
1557 	return 0;
1558 }
1559 
1560 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
1561 {
1562 	struct request_queue *q = bdev_get_queue(bdev);
1563 
1564 	if (q)
1565 		return q->limits.max_write_zeroes_sectors;
1566 
1567 	return 0;
1568 }
1569 
1570 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
1571 {
1572 	struct request_queue *q = bdev_get_queue(bdev);
1573 
1574 	if (q)
1575 		return blk_queue_zoned_model(q);
1576 
1577 	return BLK_ZONED_NONE;
1578 }
1579 
1580 static inline bool bdev_is_zoned(struct block_device *bdev)
1581 {
1582 	struct request_queue *q = bdev_get_queue(bdev);
1583 
1584 	if (q)
1585 		return blk_queue_is_zoned(q);
1586 
1587 	return false;
1588 }
1589 
1590 static inline sector_t bdev_zone_sectors(struct block_device *bdev)
1591 {
1592 	struct request_queue *q = bdev_get_queue(bdev);
1593 
1594 	if (q)
1595 		return blk_queue_zone_sectors(q);
1596 	return 0;
1597 }
1598 
1599 static inline unsigned int bdev_max_open_zones(struct block_device *bdev)
1600 {
1601 	struct request_queue *q = bdev_get_queue(bdev);
1602 
1603 	if (q)
1604 		return queue_max_open_zones(q);
1605 	return 0;
1606 }
1607 
1608 static inline unsigned int bdev_max_active_zones(struct block_device *bdev)
1609 {
1610 	struct request_queue *q = bdev_get_queue(bdev);
1611 
1612 	if (q)
1613 		return queue_max_active_zones(q);
1614 	return 0;
1615 }
1616 
1617 static inline int queue_dma_alignment(const struct request_queue *q)
1618 {
1619 	return q ? q->dma_alignment : 511;
1620 }
1621 
1622 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1623 				 unsigned int len)
1624 {
1625 	unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1626 	return !(addr & alignment) && !(len & alignment);
1627 }
1628 
1629 /* assumes size > 256 */
1630 static inline unsigned int blksize_bits(unsigned int size)
1631 {
1632 	unsigned int bits = 8;
1633 	do {
1634 		bits++;
1635 		size >>= 1;
1636 	} while (size > 256);
1637 	return bits;
1638 }
1639 
1640 static inline unsigned int block_size(struct block_device *bdev)
1641 {
1642 	return 1 << bdev->bd_inode->i_blkbits;
1643 }
1644 
1645 int kblockd_schedule_work(struct work_struct *work);
1646 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1647 
1648 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1649 	MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1650 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1651 	MODULE_ALIAS("block-major-" __stringify(major) "-*")
1652 
1653 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1654 
1655 enum blk_integrity_flags {
1656 	BLK_INTEGRITY_VERIFY		= 1 << 0,
1657 	BLK_INTEGRITY_GENERATE		= 1 << 1,
1658 	BLK_INTEGRITY_DEVICE_CAPABLE	= 1 << 2,
1659 	BLK_INTEGRITY_IP_CHECKSUM	= 1 << 3,
1660 };
1661 
1662 struct blk_integrity_iter {
1663 	void			*prot_buf;
1664 	void			*data_buf;
1665 	sector_t		seed;
1666 	unsigned int		data_size;
1667 	unsigned short		interval;
1668 	const char		*disk_name;
1669 };
1670 
1671 typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
1672 typedef void (integrity_prepare_fn) (struct request *);
1673 typedef void (integrity_complete_fn) (struct request *, unsigned int);
1674 
1675 struct blk_integrity_profile {
1676 	integrity_processing_fn		*generate_fn;
1677 	integrity_processing_fn		*verify_fn;
1678 	integrity_prepare_fn		*prepare_fn;
1679 	integrity_complete_fn		*complete_fn;
1680 	const char			*name;
1681 };
1682 
1683 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1684 extern void blk_integrity_unregister(struct gendisk *);
1685 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1686 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1687 				   struct scatterlist *);
1688 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1689 
1690 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1691 {
1692 	struct blk_integrity *bi = &disk->queue->integrity;
1693 
1694 	if (!bi->profile)
1695 		return NULL;
1696 
1697 	return bi;
1698 }
1699 
1700 static inline
1701 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1702 {
1703 	return blk_get_integrity(bdev->bd_disk);
1704 }
1705 
1706 static inline bool
1707 blk_integrity_queue_supports_integrity(struct request_queue *q)
1708 {
1709 	return q->integrity.profile;
1710 }
1711 
1712 static inline bool blk_integrity_rq(struct request *rq)
1713 {
1714 	return rq->cmd_flags & REQ_INTEGRITY;
1715 }
1716 
1717 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1718 						    unsigned int segs)
1719 {
1720 	q->limits.max_integrity_segments = segs;
1721 }
1722 
1723 static inline unsigned short
1724 queue_max_integrity_segments(const struct request_queue *q)
1725 {
1726 	return q->limits.max_integrity_segments;
1727 }
1728 
1729 /**
1730  * bio_integrity_intervals - Return number of integrity intervals for a bio
1731  * @bi:		blk_integrity profile for device
1732  * @sectors:	Size of the bio in 512-byte sectors
1733  *
1734  * Description: The block layer calculates everything in 512 byte
1735  * sectors but integrity metadata is done in terms of the data integrity
1736  * interval size of the storage device.  Convert the block layer sectors
1737  * to the appropriate number of integrity intervals.
1738  */
1739 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1740 						   unsigned int sectors)
1741 {
1742 	return sectors >> (bi->interval_exp - 9);
1743 }
1744 
1745 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1746 					       unsigned int sectors)
1747 {
1748 	return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
1749 }
1750 
1751 /*
1752  * Return the first bvec that contains integrity data.  Only drivers that are
1753  * limited to a single integrity segment should use this helper.
1754  */
1755 static inline struct bio_vec *rq_integrity_vec(struct request *rq)
1756 {
1757 	if (WARN_ON_ONCE(queue_max_integrity_segments(rq->q) > 1))
1758 		return NULL;
1759 	return rq->bio->bi_integrity->bip_vec;
1760 }
1761 
1762 #else /* CONFIG_BLK_DEV_INTEGRITY */
1763 
1764 struct bio;
1765 struct block_device;
1766 struct gendisk;
1767 struct blk_integrity;
1768 
1769 static inline int blk_integrity_rq(struct request *rq)
1770 {
1771 	return 0;
1772 }
1773 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1774 					    struct bio *b)
1775 {
1776 	return 0;
1777 }
1778 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1779 					  struct bio *b,
1780 					  struct scatterlist *s)
1781 {
1782 	return 0;
1783 }
1784 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1785 {
1786 	return NULL;
1787 }
1788 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1789 {
1790 	return NULL;
1791 }
1792 static inline bool
1793 blk_integrity_queue_supports_integrity(struct request_queue *q)
1794 {
1795 	return false;
1796 }
1797 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1798 {
1799 	return 0;
1800 }
1801 static inline void blk_integrity_register(struct gendisk *d,
1802 					 struct blk_integrity *b)
1803 {
1804 }
1805 static inline void blk_integrity_unregister(struct gendisk *d)
1806 {
1807 }
1808 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1809 						    unsigned int segs)
1810 {
1811 }
1812 static inline unsigned short queue_max_integrity_segments(const struct request_queue *q)
1813 {
1814 	return 0;
1815 }
1816 
1817 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1818 						   unsigned int sectors)
1819 {
1820 	return 0;
1821 }
1822 
1823 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1824 					       unsigned int sectors)
1825 {
1826 	return 0;
1827 }
1828 
1829 static inline struct bio_vec *rq_integrity_vec(struct request *rq)
1830 {
1831 	return NULL;
1832 }
1833 
1834 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1835 
1836 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
1837 
1838 bool blk_ksm_register(struct blk_keyslot_manager *ksm, struct request_queue *q);
1839 
1840 void blk_ksm_unregister(struct request_queue *q);
1841 
1842 #else /* CONFIG_BLK_INLINE_ENCRYPTION */
1843 
1844 static inline bool blk_ksm_register(struct blk_keyslot_manager *ksm,
1845 				    struct request_queue *q)
1846 {
1847 	return true;
1848 }
1849 
1850 static inline void blk_ksm_unregister(struct request_queue *q) { }
1851 
1852 #endif /* CONFIG_BLK_INLINE_ENCRYPTION */
1853 
1854 
1855 struct block_device_operations {
1856 	blk_qc_t (*submit_bio) (struct bio *bio);
1857 	int (*open) (struct block_device *, fmode_t);
1858 	void (*release) (struct gendisk *, fmode_t);
1859 	int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
1860 	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1861 	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1862 	unsigned int (*check_events) (struct gendisk *disk,
1863 				      unsigned int clearing);
1864 	void (*unlock_native_capacity) (struct gendisk *);
1865 	int (*getgeo)(struct block_device *, struct hd_geometry *);
1866 	int (*set_read_only)(struct block_device *bdev, bool ro);
1867 	/* this callback is with swap_lock and sometimes page table lock held */
1868 	void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1869 	int (*report_zones)(struct gendisk *, sector_t sector,
1870 			unsigned int nr_zones, report_zones_cb cb, void *data);
1871 	char *(*devnode)(struct gendisk *disk, umode_t *mode);
1872 	struct module *owner;
1873 	const struct pr_ops *pr_ops;
1874 };
1875 
1876 #ifdef CONFIG_COMPAT
1877 extern int blkdev_compat_ptr_ioctl(struct block_device *, fmode_t,
1878 				      unsigned int, unsigned long);
1879 #else
1880 #define blkdev_compat_ptr_ioctl NULL
1881 #endif
1882 
1883 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1884 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1885 						struct writeback_control *);
1886 
1887 #ifdef CONFIG_BLK_DEV_ZONED
1888 bool blk_req_needs_zone_write_lock(struct request *rq);
1889 bool blk_req_zone_write_trylock(struct request *rq);
1890 void __blk_req_zone_write_lock(struct request *rq);
1891 void __blk_req_zone_write_unlock(struct request *rq);
1892 
1893 static inline void blk_req_zone_write_lock(struct request *rq)
1894 {
1895 	if (blk_req_needs_zone_write_lock(rq))
1896 		__blk_req_zone_write_lock(rq);
1897 }
1898 
1899 static inline void blk_req_zone_write_unlock(struct request *rq)
1900 {
1901 	if (rq->rq_flags & RQF_ZONE_WRITE_LOCKED)
1902 		__blk_req_zone_write_unlock(rq);
1903 }
1904 
1905 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1906 {
1907 	return rq->q->seq_zones_wlock &&
1908 		test_bit(blk_rq_zone_no(rq), rq->q->seq_zones_wlock);
1909 }
1910 
1911 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1912 {
1913 	if (!blk_req_needs_zone_write_lock(rq))
1914 		return true;
1915 	return !blk_req_zone_is_write_locked(rq);
1916 }
1917 #else
1918 static inline bool blk_req_needs_zone_write_lock(struct request *rq)
1919 {
1920 	return false;
1921 }
1922 
1923 static inline void blk_req_zone_write_lock(struct request *rq)
1924 {
1925 }
1926 
1927 static inline void blk_req_zone_write_unlock(struct request *rq)
1928 {
1929 }
1930 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1931 {
1932 	return false;
1933 }
1934 
1935 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1936 {
1937 	return true;
1938 }
1939 #endif /* CONFIG_BLK_DEV_ZONED */
1940 
1941 static inline void blk_wake_io_task(struct task_struct *waiter)
1942 {
1943 	/*
1944 	 * If we're polling, the task itself is doing the completions. For
1945 	 * that case, we don't need to signal a wakeup, it's enough to just
1946 	 * mark us as RUNNING.
1947 	 */
1948 	if (waiter == current)
1949 		__set_current_state(TASK_RUNNING);
1950 	else
1951 		wake_up_process(waiter);
1952 }
1953 
1954 unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,
1955 		unsigned int op);
1956 void disk_end_io_acct(struct gendisk *disk, unsigned int op,
1957 		unsigned long start_time);
1958 
1959 unsigned long bio_start_io_acct(struct bio *bio);
1960 void bio_end_io_acct_remapped(struct bio *bio, unsigned long start_time,
1961 		struct block_device *orig_bdev);
1962 
1963 /**
1964  * bio_end_io_acct - end I/O accounting for bio based drivers
1965  * @bio:	bio to end account for
1966  * @start:	start time returned by bio_start_io_acct()
1967  */
1968 static inline void bio_end_io_acct(struct bio *bio, unsigned long start_time)
1969 {
1970 	return bio_end_io_acct_remapped(bio, start_time, bio->bi_bdev);
1971 }
1972 
1973 int bdev_read_only(struct block_device *bdev);
1974 int set_blocksize(struct block_device *bdev, int size);
1975 
1976 const char *bdevname(struct block_device *bdev, char *buffer);
1977 int lookup_bdev(const char *pathname, dev_t *dev);
1978 
1979 void blkdev_show(struct seq_file *seqf, off_t offset);
1980 
1981 #define BDEVNAME_SIZE	32	/* Largest string for a blockdev identifier */
1982 #define BDEVT_SIZE	10	/* Largest string for MAJ:MIN for blkdev */
1983 #ifdef CONFIG_BLOCK
1984 #define BLKDEV_MAJOR_MAX	512
1985 #else
1986 #define BLKDEV_MAJOR_MAX	0
1987 #endif
1988 
1989 struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
1990 		void *holder);
1991 struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, void *holder);
1992 int bd_prepare_to_claim(struct block_device *bdev, void *holder);
1993 void bd_abort_claiming(struct block_device *bdev, void *holder);
1994 void blkdev_put(struct block_device *bdev, fmode_t mode);
1995 
1996 /* just for blk-cgroup, don't use elsewhere */
1997 struct block_device *blkdev_get_no_open(dev_t dev);
1998 void blkdev_put_no_open(struct block_device *bdev);
1999 
2000 struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
2001 void bdev_add(struct block_device *bdev, dev_t dev);
2002 struct block_device *I_BDEV(struct inode *inode);
2003 struct block_device *bdgrab(struct block_device *bdev);
2004 void bdput(struct block_device *);
2005 int truncate_bdev_range(struct block_device *bdev, fmode_t mode, loff_t lstart,
2006 		loff_t lend);
2007 
2008 #ifdef CONFIG_BLOCK
2009 void invalidate_bdev(struct block_device *bdev);
2010 int sync_blockdev(struct block_device *bdev);
2011 #else
2012 static inline void invalidate_bdev(struct block_device *bdev)
2013 {
2014 }
2015 static inline int sync_blockdev(struct block_device *bdev)
2016 {
2017 	return 0;
2018 }
2019 #endif
2020 int fsync_bdev(struct block_device *bdev);
2021 
2022 int freeze_bdev(struct block_device *bdev);
2023 int thaw_bdev(struct block_device *bdev);
2024 
2025 #endif /* _LINUX_BLKDEV_H */
2026