xref: /linux-6.15/include/linux/blkdev.h (revision ef04d4ff)
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 unsigned short req_get_ioprio(struct request *req)
276 {
277 	return req->ioprio;
278 }
279 
280 #include <linux/elevator.h>
281 
282 struct blk_queue_ctx;
283 
284 struct bio_vec;
285 
286 enum blk_eh_timer_return {
287 	BLK_EH_DONE,		/* drivers has completed the command */
288 	BLK_EH_RESET_TIMER,	/* reset timer and try again */
289 };
290 
291 enum blk_queue_state {
292 	Queue_down,
293 	Queue_up,
294 };
295 
296 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
297 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
298 
299 #define BLK_SCSI_MAX_CMDS	(256)
300 #define BLK_SCSI_CMD_PER_LONG	(BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
301 
302 /*
303  * Zoned block device models (zoned limit).
304  *
305  * Note: This needs to be ordered from the least to the most severe
306  * restrictions for the inheritance in blk_stack_limits() to work.
307  */
308 enum blk_zoned_model {
309 	BLK_ZONED_NONE = 0,	/* Regular block device */
310 	BLK_ZONED_HA,		/* Host-aware zoned block device */
311 	BLK_ZONED_HM,		/* Host-managed zoned block device */
312 };
313 
314 struct queue_limits {
315 	unsigned long		bounce_pfn;
316 	unsigned long		seg_boundary_mask;
317 	unsigned long		virt_boundary_mask;
318 
319 	unsigned int		max_hw_sectors;
320 	unsigned int		max_dev_sectors;
321 	unsigned int		chunk_sectors;
322 	unsigned int		max_sectors;
323 	unsigned int		max_segment_size;
324 	unsigned int		physical_block_size;
325 	unsigned int		logical_block_size;
326 	unsigned int		alignment_offset;
327 	unsigned int		io_min;
328 	unsigned int		io_opt;
329 	unsigned int		max_discard_sectors;
330 	unsigned int		max_hw_discard_sectors;
331 	unsigned int		max_write_same_sectors;
332 	unsigned int		max_write_zeroes_sectors;
333 	unsigned int		max_zone_append_sectors;
334 	unsigned int		discard_granularity;
335 	unsigned int		discard_alignment;
336 	unsigned int		zone_write_granularity;
337 
338 	unsigned short		max_segments;
339 	unsigned short		max_integrity_segments;
340 	unsigned short		max_discard_segments;
341 
342 	unsigned char		misaligned;
343 	unsigned char		discard_misaligned;
344 	unsigned char		raid_partial_stripes_expensive;
345 	enum blk_zoned_model	zoned;
346 };
347 
348 typedef int (*report_zones_cb)(struct blk_zone *zone, unsigned int idx,
349 			       void *data);
350 
351 void blk_queue_set_zoned(struct gendisk *disk, enum blk_zoned_model model);
352 
353 #ifdef CONFIG_BLK_DEV_ZONED
354 
355 #define BLK_ALL_ZONES  ((unsigned int)-1)
356 int blkdev_report_zones(struct block_device *bdev, sector_t sector,
357 			unsigned int nr_zones, report_zones_cb cb, void *data);
358 unsigned int blkdev_nr_zones(struct gendisk *disk);
359 extern int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
360 			    sector_t sectors, sector_t nr_sectors,
361 			    gfp_t gfp_mask);
362 int blk_revalidate_disk_zones(struct gendisk *disk,
363 			      void (*update_driver_data)(struct gendisk *disk));
364 
365 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
366 				     unsigned int cmd, unsigned long arg);
367 extern int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
368 				  unsigned int cmd, unsigned long arg);
369 
370 #else /* CONFIG_BLK_DEV_ZONED */
371 
372 static inline unsigned int blkdev_nr_zones(struct gendisk *disk)
373 {
374 	return 0;
375 }
376 
377 static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
378 					    fmode_t mode, unsigned int cmd,
379 					    unsigned long arg)
380 {
381 	return -ENOTTY;
382 }
383 
384 static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
385 					 fmode_t mode, unsigned int cmd,
386 					 unsigned long arg)
387 {
388 	return -ENOTTY;
389 }
390 
391 #endif /* CONFIG_BLK_DEV_ZONED */
392 
393 struct request_queue {
394 	struct request		*last_merge;
395 	struct elevator_queue	*elevator;
396 
397 	struct percpu_ref	q_usage_counter;
398 
399 	struct blk_queue_stats	*stats;
400 	struct rq_qos		*rq_qos;
401 
402 	const struct blk_mq_ops	*mq_ops;
403 
404 	/* sw queues */
405 	struct blk_mq_ctx __percpu	*queue_ctx;
406 
407 	unsigned int		queue_depth;
408 
409 	/* hw dispatch queues */
410 	struct blk_mq_hw_ctx	**queue_hw_ctx;
411 	unsigned int		nr_hw_queues;
412 
413 	struct backing_dev_info	*backing_dev_info;
414 
415 	/*
416 	 * The queue owner gets to use this for whatever they like.
417 	 * ll_rw_blk doesn't touch it.
418 	 */
419 	void			*queuedata;
420 
421 	/*
422 	 * various queue flags, see QUEUE_* below
423 	 */
424 	unsigned long		queue_flags;
425 	/*
426 	 * Number of contexts that have called blk_set_pm_only(). If this
427 	 * counter is above zero then only RQF_PM requests are processed.
428 	 */
429 	atomic_t		pm_only;
430 
431 	/*
432 	 * ida allocated id for this queue.  Used to index queues from
433 	 * ioctx.
434 	 */
435 	int			id;
436 
437 	/*
438 	 * queue needs bounce pages for pages above this limit
439 	 */
440 	gfp_t			bounce_gfp;
441 
442 	spinlock_t		queue_lock;
443 
444 	/*
445 	 * queue kobject
446 	 */
447 	struct kobject kobj;
448 
449 	/*
450 	 * mq queue kobject
451 	 */
452 	struct kobject *mq_kobj;
453 
454 #ifdef  CONFIG_BLK_DEV_INTEGRITY
455 	struct blk_integrity integrity;
456 #endif	/* CONFIG_BLK_DEV_INTEGRITY */
457 
458 #ifdef CONFIG_PM
459 	struct device		*dev;
460 	enum rpm_status		rpm_status;
461 #endif
462 
463 	/*
464 	 * queue settings
465 	 */
466 	unsigned long		nr_requests;	/* Max # of requests */
467 
468 	unsigned int		dma_pad_mask;
469 	unsigned int		dma_alignment;
470 
471 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
472 	/* Inline crypto capabilities */
473 	struct blk_keyslot_manager *ksm;
474 #endif
475 
476 	unsigned int		rq_timeout;
477 	int			poll_nsec;
478 
479 	struct blk_stat_callback	*poll_cb;
480 	struct blk_rq_stat	poll_stat[BLK_MQ_POLL_STATS_BKTS];
481 
482 	struct timer_list	timeout;
483 	struct work_struct	timeout_work;
484 
485 	atomic_t		nr_active_requests_shared_sbitmap;
486 
487 	struct list_head	icq_list;
488 #ifdef CONFIG_BLK_CGROUP
489 	DECLARE_BITMAP		(blkcg_pols, BLKCG_MAX_POLS);
490 	struct blkcg_gq		*root_blkg;
491 	struct list_head	blkg_list;
492 #endif
493 
494 	struct queue_limits	limits;
495 
496 	unsigned int		required_elevator_features;
497 
498 #ifdef CONFIG_BLK_DEV_ZONED
499 	/*
500 	 * Zoned block device information for request dispatch control.
501 	 * nr_zones is the total number of zones of the device. This is always
502 	 * 0 for regular block devices. conv_zones_bitmap is a bitmap of nr_zones
503 	 * bits which indicates if a zone is conventional (bit set) or
504 	 * sequential (bit clear). seq_zones_wlock is a bitmap of nr_zones
505 	 * bits which indicates if a zone is write locked, that is, if a write
506 	 * request targeting the zone was dispatched. All three fields are
507 	 * initialized by the low level device driver (e.g. scsi/sd.c).
508 	 * Stacking drivers (device mappers) may or may not initialize
509 	 * these fields.
510 	 *
511 	 * Reads of this information must be protected with blk_queue_enter() /
512 	 * blk_queue_exit(). Modifying this information is only allowed while
513 	 * no requests are being processed. See also blk_mq_freeze_queue() and
514 	 * blk_mq_unfreeze_queue().
515 	 */
516 	unsigned int		nr_zones;
517 	unsigned long		*conv_zones_bitmap;
518 	unsigned long		*seq_zones_wlock;
519 	unsigned int		max_open_zones;
520 	unsigned int		max_active_zones;
521 #endif /* CONFIG_BLK_DEV_ZONED */
522 
523 	/*
524 	 * sg stuff
525 	 */
526 	unsigned int		sg_timeout;
527 	unsigned int		sg_reserved_size;
528 	int			node;
529 	struct mutex		debugfs_mutex;
530 #ifdef CONFIG_BLK_DEV_IO_TRACE
531 	struct blk_trace __rcu	*blk_trace;
532 #endif
533 	/*
534 	 * for flush operations
535 	 */
536 	struct blk_flush_queue	*fq;
537 
538 	struct list_head	requeue_list;
539 	spinlock_t		requeue_lock;
540 	struct delayed_work	requeue_work;
541 
542 	struct mutex		sysfs_lock;
543 	struct mutex		sysfs_dir_lock;
544 
545 	/*
546 	 * for reusing dead hctx instance in case of updating
547 	 * nr_hw_queues
548 	 */
549 	struct list_head	unused_hctx_list;
550 	spinlock_t		unused_hctx_lock;
551 
552 	int			mq_freeze_depth;
553 
554 #if defined(CONFIG_BLK_DEV_BSG)
555 	struct bsg_class_device bsg_dev;
556 #endif
557 
558 #ifdef CONFIG_BLK_DEV_THROTTLING
559 	/* Throttle data */
560 	struct throtl_data *td;
561 #endif
562 	struct rcu_head		rcu_head;
563 	wait_queue_head_t	mq_freeze_wq;
564 	/*
565 	 * Protect concurrent access to q_usage_counter by
566 	 * percpu_ref_kill() and percpu_ref_reinit().
567 	 */
568 	struct mutex		mq_freeze_lock;
569 
570 	struct blk_mq_tag_set	*tag_set;
571 	struct list_head	tag_set_list;
572 	struct bio_set		bio_split;
573 
574 	struct dentry		*debugfs_dir;
575 
576 #ifdef CONFIG_BLK_DEBUG_FS
577 	struct dentry		*sched_debugfs_dir;
578 	struct dentry		*rqos_debugfs_dir;
579 #endif
580 
581 	bool			mq_sysfs_init_done;
582 
583 	size_t			cmd_size;
584 
585 #define BLK_MAX_WRITE_HINTS	5
586 	u64			write_hints[BLK_MAX_WRITE_HINTS];
587 };
588 
589 /* Keep blk_queue_flag_name[] in sync with the definitions below */
590 #define QUEUE_FLAG_STOPPED	0	/* queue is stopped */
591 #define QUEUE_FLAG_DYING	1	/* queue being torn down */
592 #define QUEUE_FLAG_NOMERGES     3	/* disable merge attempts */
593 #define QUEUE_FLAG_SAME_COMP	4	/* complete on same CPU-group */
594 #define QUEUE_FLAG_FAIL_IO	5	/* fake timeout */
595 #define QUEUE_FLAG_NONROT	6	/* non-rotational device (SSD) */
596 #define QUEUE_FLAG_VIRT		QUEUE_FLAG_NONROT /* paravirt device */
597 #define QUEUE_FLAG_IO_STAT	7	/* do disk/partitions IO accounting */
598 #define QUEUE_FLAG_DISCARD	8	/* supports DISCARD */
599 #define QUEUE_FLAG_NOXMERGES	9	/* No extended merges */
600 #define QUEUE_FLAG_ADD_RANDOM	10	/* Contributes to random pool */
601 #define QUEUE_FLAG_SECERASE	11	/* supports secure erase */
602 #define QUEUE_FLAG_SAME_FORCE	12	/* force complete on same CPU */
603 #define QUEUE_FLAG_DEAD		13	/* queue tear-down finished */
604 #define QUEUE_FLAG_INIT_DONE	14	/* queue is initialized */
605 #define QUEUE_FLAG_STABLE_WRITES 15	/* don't modify blks until WB is done */
606 #define QUEUE_FLAG_POLL		16	/* IO polling enabled if set */
607 #define QUEUE_FLAG_WC		17	/* Write back caching */
608 #define QUEUE_FLAG_FUA		18	/* device supports FUA writes */
609 #define QUEUE_FLAG_DAX		19	/* device supports DAX */
610 #define QUEUE_FLAG_STATS	20	/* track IO start and completion times */
611 #define QUEUE_FLAG_POLL_STATS	21	/* collecting stats for hybrid polling */
612 #define QUEUE_FLAG_REGISTERED	22	/* queue has been registered to a disk */
613 #define QUEUE_FLAG_SCSI_PASSTHROUGH 23	/* queue supports SCSI commands */
614 #define QUEUE_FLAG_QUIESCED	24	/* queue has been quiesced */
615 #define QUEUE_FLAG_PCI_P2PDMA	25	/* device supports PCI p2p requests */
616 #define QUEUE_FLAG_ZONE_RESETALL 26	/* supports Zone Reset All */
617 #define QUEUE_FLAG_RQ_ALLOC_TIME 27	/* record rq->alloc_time_ns */
618 #define QUEUE_FLAG_HCTX_ACTIVE	28	/* at least one blk-mq hctx is active */
619 #define QUEUE_FLAG_NOWAIT       29	/* device supports NOWAIT */
620 
621 #define QUEUE_FLAG_MQ_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
622 				 (1 << QUEUE_FLAG_SAME_COMP) |		\
623 				 (1 << QUEUE_FLAG_NOWAIT))
624 
625 void blk_queue_flag_set(unsigned int flag, struct request_queue *q);
626 void blk_queue_flag_clear(unsigned int flag, struct request_queue *q);
627 bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);
628 
629 #define blk_queue_stopped(q)	test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
630 #define blk_queue_dying(q)	test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
631 #define blk_queue_dead(q)	test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
632 #define blk_queue_init_done(q)	test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
633 #define blk_queue_nomerges(q)	test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
634 #define blk_queue_noxmerges(q)	\
635 	test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
636 #define blk_queue_nonrot(q)	test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
637 #define blk_queue_stable_writes(q) \
638 	test_bit(QUEUE_FLAG_STABLE_WRITES, &(q)->queue_flags)
639 #define blk_queue_io_stat(q)	test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
640 #define blk_queue_add_random(q)	test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
641 #define blk_queue_discard(q)	test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
642 #define blk_queue_zone_resetall(q)	\
643 	test_bit(QUEUE_FLAG_ZONE_RESETALL, &(q)->queue_flags)
644 #define blk_queue_secure_erase(q) \
645 	(test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
646 #define blk_queue_dax(q)	test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
647 #define blk_queue_scsi_passthrough(q)	\
648 	test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags)
649 #define blk_queue_pci_p2pdma(q)	\
650 	test_bit(QUEUE_FLAG_PCI_P2PDMA, &(q)->queue_flags)
651 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
652 #define blk_queue_rq_alloc_time(q)	\
653 	test_bit(QUEUE_FLAG_RQ_ALLOC_TIME, &(q)->queue_flags)
654 #else
655 #define blk_queue_rq_alloc_time(q)	false
656 #endif
657 
658 #define blk_noretry_request(rq) \
659 	((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
660 			     REQ_FAILFAST_DRIVER))
661 #define blk_queue_quiesced(q)	test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
662 #define blk_queue_pm_only(q)	atomic_read(&(q)->pm_only)
663 #define blk_queue_fua(q)	test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags)
664 #define blk_queue_registered(q)	test_bit(QUEUE_FLAG_REGISTERED, &(q)->queue_flags)
665 #define blk_queue_nowait(q)	test_bit(QUEUE_FLAG_NOWAIT, &(q)->queue_flags)
666 
667 extern void blk_set_pm_only(struct request_queue *q);
668 extern void blk_clear_pm_only(struct request_queue *q);
669 
670 static inline bool blk_account_rq(struct request *rq)
671 {
672 	return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq);
673 }
674 
675 #define list_entry_rq(ptr)	list_entry((ptr), struct request, queuelist)
676 
677 #define rq_data_dir(rq)		(op_is_write(req_op(rq)) ? WRITE : READ)
678 
679 #define rq_dma_dir(rq) \
680 	(op_is_write(req_op(rq)) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
681 
682 #define dma_map_bvec(dev, bv, dir, attrs) \
683 	dma_map_page_attrs(dev, (bv)->bv_page, (bv)->bv_offset, (bv)->bv_len, \
684 	(dir), (attrs))
685 
686 static inline bool queue_is_mq(struct request_queue *q)
687 {
688 	return q->mq_ops;
689 }
690 
691 #ifdef CONFIG_PM
692 static inline enum rpm_status queue_rpm_status(struct request_queue *q)
693 {
694 	return q->rpm_status;
695 }
696 #else
697 static inline enum rpm_status queue_rpm_status(struct request_queue *q)
698 {
699 	return RPM_ACTIVE;
700 }
701 #endif
702 
703 static inline enum blk_zoned_model
704 blk_queue_zoned_model(struct request_queue *q)
705 {
706 	if (IS_ENABLED(CONFIG_BLK_DEV_ZONED))
707 		return q->limits.zoned;
708 	return BLK_ZONED_NONE;
709 }
710 
711 static inline bool blk_queue_is_zoned(struct request_queue *q)
712 {
713 	switch (blk_queue_zoned_model(q)) {
714 	case BLK_ZONED_HA:
715 	case BLK_ZONED_HM:
716 		return true;
717 	default:
718 		return false;
719 	}
720 }
721 
722 static inline sector_t blk_queue_zone_sectors(struct request_queue *q)
723 {
724 	return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0;
725 }
726 
727 #ifdef CONFIG_BLK_DEV_ZONED
728 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
729 {
730 	return blk_queue_is_zoned(q) ? q->nr_zones : 0;
731 }
732 
733 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
734 					     sector_t sector)
735 {
736 	if (!blk_queue_is_zoned(q))
737 		return 0;
738 	return sector >> ilog2(q->limits.chunk_sectors);
739 }
740 
741 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
742 					 sector_t sector)
743 {
744 	if (!blk_queue_is_zoned(q))
745 		return false;
746 	if (!q->conv_zones_bitmap)
747 		return true;
748 	return !test_bit(blk_queue_zone_no(q, sector), q->conv_zones_bitmap);
749 }
750 
751 static inline void blk_queue_max_open_zones(struct request_queue *q,
752 		unsigned int max_open_zones)
753 {
754 	q->max_open_zones = max_open_zones;
755 }
756 
757 static inline unsigned int queue_max_open_zones(const struct request_queue *q)
758 {
759 	return q->max_open_zones;
760 }
761 
762 static inline void blk_queue_max_active_zones(struct request_queue *q,
763 		unsigned int max_active_zones)
764 {
765 	q->max_active_zones = max_active_zones;
766 }
767 
768 static inline unsigned int queue_max_active_zones(const struct request_queue *q)
769 {
770 	return q->max_active_zones;
771 }
772 #else /* CONFIG_BLK_DEV_ZONED */
773 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
774 {
775 	return 0;
776 }
777 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
778 					 sector_t sector)
779 {
780 	return false;
781 }
782 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
783 					     sector_t sector)
784 {
785 	return 0;
786 }
787 static inline unsigned int queue_max_open_zones(const struct request_queue *q)
788 {
789 	return 0;
790 }
791 static inline unsigned int queue_max_active_zones(const struct request_queue *q)
792 {
793 	return 0;
794 }
795 #endif /* CONFIG_BLK_DEV_ZONED */
796 
797 static inline bool rq_is_sync(struct request *rq)
798 {
799 	return op_is_sync(rq->cmd_flags);
800 }
801 
802 static inline bool rq_mergeable(struct request *rq)
803 {
804 	if (blk_rq_is_passthrough(rq))
805 		return false;
806 
807 	if (req_op(rq) == REQ_OP_FLUSH)
808 		return false;
809 
810 	if (req_op(rq) == REQ_OP_WRITE_ZEROES)
811 		return false;
812 
813 	if (req_op(rq) == REQ_OP_ZONE_APPEND)
814 		return false;
815 
816 	if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
817 		return false;
818 	if (rq->rq_flags & RQF_NOMERGE_FLAGS)
819 		return false;
820 
821 	return true;
822 }
823 
824 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
825 {
826 	if (bio_page(a) == bio_page(b) &&
827 	    bio_offset(a) == bio_offset(b))
828 		return true;
829 
830 	return false;
831 }
832 
833 static inline unsigned int blk_queue_depth(struct request_queue *q)
834 {
835 	if (q->queue_depth)
836 		return q->queue_depth;
837 
838 	return q->nr_requests;
839 }
840 
841 extern unsigned long blk_max_low_pfn, blk_max_pfn;
842 
843 /*
844  * standard bounce addresses:
845  *
846  * BLK_BOUNCE_HIGH	: bounce all highmem pages
847  * BLK_BOUNCE_ANY	: don't bounce anything
848  * BLK_BOUNCE_ISA	: bounce pages above ISA DMA boundary
849  */
850 
851 #if BITS_PER_LONG == 32
852 #define BLK_BOUNCE_HIGH		((u64)blk_max_low_pfn << PAGE_SHIFT)
853 #else
854 #define BLK_BOUNCE_HIGH		-1ULL
855 #endif
856 #define BLK_BOUNCE_ANY		(-1ULL)
857 #define BLK_BOUNCE_ISA		(DMA_BIT_MASK(24))
858 
859 /*
860  * default timeout for SG_IO if none specified
861  */
862 #define BLK_DEFAULT_SG_TIMEOUT	(60 * HZ)
863 #define BLK_MIN_SG_TIMEOUT	(7 * HZ)
864 
865 struct rq_map_data {
866 	struct page **pages;
867 	int page_order;
868 	int nr_entries;
869 	unsigned long offset;
870 	int null_mapped;
871 	int from_user;
872 };
873 
874 struct req_iterator {
875 	struct bvec_iter iter;
876 	struct bio *bio;
877 };
878 
879 /* This should not be used directly - use rq_for_each_segment */
880 #define for_each_bio(_bio)		\
881 	for (; _bio; _bio = _bio->bi_next)
882 #define __rq_for_each_bio(_bio, rq)	\
883 	if ((rq->bio))			\
884 		for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
885 
886 #define rq_for_each_segment(bvl, _rq, _iter)			\
887 	__rq_for_each_bio(_iter.bio, _rq)			\
888 		bio_for_each_segment(bvl, _iter.bio, _iter.iter)
889 
890 #define rq_for_each_bvec(bvl, _rq, _iter)			\
891 	__rq_for_each_bio(_iter.bio, _rq)			\
892 		bio_for_each_bvec(bvl, _iter.bio, _iter.iter)
893 
894 #define rq_iter_last(bvec, _iter)				\
895 		(_iter.bio->bi_next == NULL &&			\
896 		 bio_iter_last(bvec, _iter.iter))
897 
898 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
899 # error	"You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
900 #endif
901 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
902 extern void rq_flush_dcache_pages(struct request *rq);
903 #else
904 static inline void rq_flush_dcache_pages(struct request *rq)
905 {
906 }
907 #endif
908 
909 extern int blk_register_queue(struct gendisk *disk);
910 extern void blk_unregister_queue(struct gendisk *disk);
911 blk_qc_t submit_bio_noacct(struct bio *bio);
912 extern void blk_rq_init(struct request_queue *q, struct request *rq);
913 extern void blk_put_request(struct request *);
914 extern struct request *blk_get_request(struct request_queue *, unsigned int op,
915 				       blk_mq_req_flags_t flags);
916 extern int blk_lld_busy(struct request_queue *q);
917 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
918 			     struct bio_set *bs, gfp_t gfp_mask,
919 			     int (*bio_ctr)(struct bio *, struct bio *, void *),
920 			     void *data);
921 extern void blk_rq_unprep_clone(struct request *rq);
922 extern blk_status_t blk_insert_cloned_request(struct request_queue *q,
923 				     struct request *rq);
924 extern int blk_rq_append_bio(struct request *rq, struct bio **bio);
925 extern void blk_queue_split(struct bio **);
926 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
927 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
928 			      unsigned int, void __user *);
929 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
930 			  unsigned int, void __user *);
931 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
932 			 struct scsi_ioctl_command __user *);
933 extern int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp);
934 extern int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp);
935 
936 extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
937 extern void blk_queue_exit(struct request_queue *q);
938 extern void blk_sync_queue(struct request_queue *q);
939 extern int blk_rq_map_user(struct request_queue *, struct request *,
940 			   struct rq_map_data *, void __user *, unsigned long,
941 			   gfp_t);
942 extern int blk_rq_unmap_user(struct bio *);
943 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
944 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
945 			       struct rq_map_data *, const struct iov_iter *,
946 			       gfp_t);
947 extern void blk_execute_rq(struct gendisk *, struct request *, int);
948 extern void blk_execute_rq_nowait(struct gendisk *,
949 				  struct request *, int, rq_end_io_fn *);
950 
951 /* Helper to convert REQ_OP_XXX to its string format XXX */
952 extern const char *blk_op_str(unsigned int op);
953 
954 int blk_status_to_errno(blk_status_t status);
955 blk_status_t errno_to_blk_status(int errno);
956 
957 int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin);
958 
959 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
960 {
961 	return bdev->bd_disk->queue;	/* this is never NULL */
962 }
963 
964 /*
965  * The basic unit of block I/O is a sector. It is used in a number of contexts
966  * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
967  * bytes. Variables of type sector_t represent an offset or size that is a
968  * multiple of 512 bytes. Hence these two constants.
969  */
970 #ifndef SECTOR_SHIFT
971 #define SECTOR_SHIFT 9
972 #endif
973 #ifndef SECTOR_SIZE
974 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
975 #endif
976 
977 /*
978  * blk_rq_pos()			: the current sector
979  * blk_rq_bytes()		: bytes left in the entire request
980  * blk_rq_cur_bytes()		: bytes left in the current segment
981  * blk_rq_err_bytes()		: bytes left till the next error boundary
982  * blk_rq_sectors()		: sectors left in the entire request
983  * blk_rq_cur_sectors()		: sectors left in the current segment
984  * blk_rq_stats_sectors()	: sectors of the entire request used for stats
985  */
986 static inline sector_t blk_rq_pos(const struct request *rq)
987 {
988 	return rq->__sector;
989 }
990 
991 static inline unsigned int blk_rq_bytes(const struct request *rq)
992 {
993 	return rq->__data_len;
994 }
995 
996 static inline int blk_rq_cur_bytes(const struct request *rq)
997 {
998 	return rq->bio ? bio_cur_bytes(rq->bio) : 0;
999 }
1000 
1001 extern unsigned int blk_rq_err_bytes(const struct request *rq);
1002 
1003 static inline unsigned int blk_rq_sectors(const struct request *rq)
1004 {
1005 	return blk_rq_bytes(rq) >> SECTOR_SHIFT;
1006 }
1007 
1008 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
1009 {
1010 	return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
1011 }
1012 
1013 static inline unsigned int blk_rq_stats_sectors(const struct request *rq)
1014 {
1015 	return rq->stats_sectors;
1016 }
1017 
1018 #ifdef CONFIG_BLK_DEV_ZONED
1019 
1020 /* Helper to convert BLK_ZONE_ZONE_XXX to its string format XXX */
1021 const char *blk_zone_cond_str(enum blk_zone_cond zone_cond);
1022 
1023 static inline unsigned int blk_rq_zone_no(struct request *rq)
1024 {
1025 	return blk_queue_zone_no(rq->q, blk_rq_pos(rq));
1026 }
1027 
1028 static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
1029 {
1030 	return blk_queue_zone_is_seq(rq->q, blk_rq_pos(rq));
1031 }
1032 #endif /* CONFIG_BLK_DEV_ZONED */
1033 
1034 /*
1035  * Some commands like WRITE SAME have a payload or data transfer size which
1036  * is different from the size of the request.  Any driver that supports such
1037  * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
1038  * calculate the data transfer size.
1039  */
1040 static inline unsigned int blk_rq_payload_bytes(struct request *rq)
1041 {
1042 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1043 		return rq->special_vec.bv_len;
1044 	return blk_rq_bytes(rq);
1045 }
1046 
1047 /*
1048  * Return the first full biovec in the request.  The caller needs to check that
1049  * there are any bvecs before calling this helper.
1050  */
1051 static inline struct bio_vec req_bvec(struct request *rq)
1052 {
1053 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1054 		return rq->special_vec;
1055 	return mp_bvec_iter_bvec(rq->bio->bi_io_vec, rq->bio->bi_iter);
1056 }
1057 
1058 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
1059 						     int op)
1060 {
1061 	if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
1062 		return min(q->limits.max_discard_sectors,
1063 			   UINT_MAX >> SECTOR_SHIFT);
1064 
1065 	if (unlikely(op == REQ_OP_WRITE_SAME))
1066 		return q->limits.max_write_same_sectors;
1067 
1068 	if (unlikely(op == REQ_OP_WRITE_ZEROES))
1069 		return q->limits.max_write_zeroes_sectors;
1070 
1071 	return q->limits.max_sectors;
1072 }
1073 
1074 /*
1075  * Return maximum size of a request at given offset. Only valid for
1076  * file system requests.
1077  */
1078 static inline unsigned int blk_max_size_offset(struct request_queue *q,
1079 					       sector_t offset,
1080 					       unsigned int chunk_sectors)
1081 {
1082 	if (!chunk_sectors) {
1083 		if (q->limits.chunk_sectors)
1084 			chunk_sectors = q->limits.chunk_sectors;
1085 		else
1086 			return q->limits.max_sectors;
1087 	}
1088 
1089 	if (likely(is_power_of_2(chunk_sectors)))
1090 		chunk_sectors -= offset & (chunk_sectors - 1);
1091 	else
1092 		chunk_sectors -= sector_div(offset, chunk_sectors);
1093 
1094 	return min(q->limits.max_sectors, chunk_sectors);
1095 }
1096 
1097 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
1098 						  sector_t offset)
1099 {
1100 	struct request_queue *q = rq->q;
1101 
1102 	if (blk_rq_is_passthrough(rq))
1103 		return q->limits.max_hw_sectors;
1104 
1105 	if (!q->limits.chunk_sectors ||
1106 	    req_op(rq) == REQ_OP_DISCARD ||
1107 	    req_op(rq) == REQ_OP_SECURE_ERASE)
1108 		return blk_queue_get_max_sectors(q, req_op(rq));
1109 
1110 	return min(blk_max_size_offset(q, offset, 0),
1111 			blk_queue_get_max_sectors(q, req_op(rq)));
1112 }
1113 
1114 static inline unsigned int blk_rq_count_bios(struct request *rq)
1115 {
1116 	unsigned int nr_bios = 0;
1117 	struct bio *bio;
1118 
1119 	__rq_for_each_bio(bio, rq)
1120 		nr_bios++;
1121 
1122 	return nr_bios;
1123 }
1124 
1125 void blk_steal_bios(struct bio_list *list, struct request *rq);
1126 
1127 /*
1128  * Request completion related functions.
1129  *
1130  * blk_update_request() completes given number of bytes and updates
1131  * the request without completing it.
1132  */
1133 extern bool blk_update_request(struct request *rq, blk_status_t error,
1134 			       unsigned int nr_bytes);
1135 
1136 extern void blk_abort_request(struct request *);
1137 
1138 /*
1139  * Access functions for manipulating queue properties
1140  */
1141 extern void blk_cleanup_queue(struct request_queue *);
1142 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1143 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1144 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1145 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1146 extern void blk_queue_max_discard_segments(struct request_queue *,
1147 		unsigned short);
1148 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1149 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1150 		unsigned int max_discard_sectors);
1151 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1152 		unsigned int max_write_same_sectors);
1153 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
1154 		unsigned int max_write_same_sectors);
1155 extern void blk_queue_logical_block_size(struct request_queue *, unsigned int);
1156 extern void blk_queue_max_zone_append_sectors(struct request_queue *q,
1157 		unsigned int max_zone_append_sectors);
1158 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1159 void blk_queue_zone_write_granularity(struct request_queue *q,
1160 				      unsigned int size);
1161 extern void blk_queue_alignment_offset(struct request_queue *q,
1162 				       unsigned int alignment);
1163 void blk_queue_update_readahead(struct request_queue *q);
1164 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1165 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1166 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1167 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1168 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth);
1169 extern void blk_set_default_limits(struct queue_limits *lim);
1170 extern void blk_set_stacking_limits(struct queue_limits *lim);
1171 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1172 			    sector_t offset);
1173 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1174 			      sector_t offset);
1175 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1176 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1177 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1178 extern void blk_queue_dma_alignment(struct request_queue *, int);
1179 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1180 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1181 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1182 extern void blk_queue_required_elevator_features(struct request_queue *q,
1183 						 unsigned int features);
1184 extern bool blk_queue_can_use_dma_map_merging(struct request_queue *q,
1185 					      struct device *dev);
1186 
1187 /*
1188  * Number of physical segments as sent to the device.
1189  *
1190  * Normally this is the number of discontiguous data segments sent by the
1191  * submitter.  But for data-less command like discard we might have no
1192  * actual data segments submitted, but the driver might have to add it's
1193  * own special payload.  In that case we still return 1 here so that this
1194  * special payload will be mapped.
1195  */
1196 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
1197 {
1198 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1199 		return 1;
1200 	return rq->nr_phys_segments;
1201 }
1202 
1203 /*
1204  * Number of discard segments (or ranges) the driver needs to fill in.
1205  * Each discard bio merged into a request is counted as one segment.
1206  */
1207 static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
1208 {
1209 	return max_t(unsigned short, rq->nr_phys_segments, 1);
1210 }
1211 
1212 int __blk_rq_map_sg(struct request_queue *q, struct request *rq,
1213 		struct scatterlist *sglist, struct scatterlist **last_sg);
1214 static inline int blk_rq_map_sg(struct request_queue *q, struct request *rq,
1215 		struct scatterlist *sglist)
1216 {
1217 	struct scatterlist *last_sg = NULL;
1218 
1219 	return __blk_rq_map_sg(q, rq, sglist, &last_sg);
1220 }
1221 extern void blk_dump_rq_flags(struct request *, char *);
1222 
1223 bool __must_check blk_get_queue(struct request_queue *);
1224 struct request_queue *blk_alloc_queue(int node_id);
1225 extern void blk_put_queue(struct request_queue *);
1226 extern void blk_set_queue_dying(struct request_queue *);
1227 
1228 #ifdef CONFIG_BLOCK
1229 /*
1230  * blk_plug permits building a queue of related requests by holding the I/O
1231  * fragments for a short period. This allows merging of sequential requests
1232  * into single larger request. As the requests are moved from a per-task list to
1233  * the device's request_queue in a batch, this results in improved scalability
1234  * as the lock contention for request_queue lock is reduced.
1235  *
1236  * It is ok not to disable preemption when adding the request to the plug list
1237  * or when attempting a merge, because blk_schedule_flush_list() will only flush
1238  * the plug list when the task sleeps by itself. For details, please see
1239  * schedule() where blk_schedule_flush_plug() is called.
1240  */
1241 struct blk_plug {
1242 	struct list_head mq_list; /* blk-mq requests */
1243 	struct list_head cb_list; /* md requires an unplug callback */
1244 	unsigned short rq_count;
1245 	bool multiple_queues;
1246 	bool nowait;
1247 };
1248 #define BLK_MAX_REQUEST_COUNT 16
1249 #define BLK_PLUG_FLUSH_SIZE (128 * 1024)
1250 
1251 struct blk_plug_cb;
1252 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1253 struct blk_plug_cb {
1254 	struct list_head list;
1255 	blk_plug_cb_fn callback;
1256 	void *data;
1257 };
1258 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1259 					     void *data, int size);
1260 extern void blk_start_plug(struct blk_plug *);
1261 extern void blk_finish_plug(struct blk_plug *);
1262 extern void blk_flush_plug_list(struct blk_plug *, bool);
1263 
1264 static inline void blk_flush_plug(struct task_struct *tsk)
1265 {
1266 	struct blk_plug *plug = tsk->plug;
1267 
1268 	if (plug)
1269 		blk_flush_plug_list(plug, false);
1270 }
1271 
1272 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1273 {
1274 	struct blk_plug *plug = tsk->plug;
1275 
1276 	if (plug)
1277 		blk_flush_plug_list(plug, true);
1278 }
1279 
1280 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1281 {
1282 	struct blk_plug *plug = tsk->plug;
1283 
1284 	return plug &&
1285 		 (!list_empty(&plug->mq_list) ||
1286 		 !list_empty(&plug->cb_list));
1287 }
1288 
1289 int blkdev_issue_flush(struct block_device *bdev);
1290 long nr_blockdev_pages(void);
1291 #else /* CONFIG_BLOCK */
1292 struct blk_plug {
1293 };
1294 
1295 static inline void blk_start_plug(struct blk_plug *plug)
1296 {
1297 }
1298 
1299 static inline void blk_finish_plug(struct blk_plug *plug)
1300 {
1301 }
1302 
1303 static inline void blk_flush_plug(struct task_struct *task)
1304 {
1305 }
1306 
1307 static inline void blk_schedule_flush_plug(struct task_struct *task)
1308 {
1309 }
1310 
1311 
1312 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1313 {
1314 	return false;
1315 }
1316 
1317 static inline int blkdev_issue_flush(struct block_device *bdev)
1318 {
1319 	return 0;
1320 }
1321 
1322 static inline long nr_blockdev_pages(void)
1323 {
1324 	return 0;
1325 }
1326 #endif /* CONFIG_BLOCK */
1327 
1328 extern void blk_io_schedule(void);
1329 
1330 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1331 		sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1332 
1333 #define BLKDEV_DISCARD_SECURE	(1 << 0)	/* issue a secure erase */
1334 
1335 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1336 		sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1337 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1338 		sector_t nr_sects, gfp_t gfp_mask, int flags,
1339 		struct bio **biop);
1340 
1341 #define BLKDEV_ZERO_NOUNMAP	(1 << 0)  /* do not free blocks */
1342 #define BLKDEV_ZERO_NOFALLBACK	(1 << 1)  /* don't write explicit zeroes */
1343 
1344 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1345 		sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
1346 		unsigned flags);
1347 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1348 		sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
1349 
1350 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1351 		sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1352 {
1353 	return blkdev_issue_discard(sb->s_bdev,
1354 				    block << (sb->s_blocksize_bits -
1355 					      SECTOR_SHIFT),
1356 				    nr_blocks << (sb->s_blocksize_bits -
1357 						  SECTOR_SHIFT),
1358 				    gfp_mask, flags);
1359 }
1360 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1361 		sector_t nr_blocks, gfp_t gfp_mask)
1362 {
1363 	return blkdev_issue_zeroout(sb->s_bdev,
1364 				    block << (sb->s_blocksize_bits -
1365 					      SECTOR_SHIFT),
1366 				    nr_blocks << (sb->s_blocksize_bits -
1367 						  SECTOR_SHIFT),
1368 				    gfp_mask, 0);
1369 }
1370 
1371 extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
1372 
1373 static inline bool bdev_is_partition(struct block_device *bdev)
1374 {
1375 	return bdev->bd_partno;
1376 }
1377 
1378 enum blk_default_limits {
1379 	BLK_MAX_SEGMENTS	= 128,
1380 	BLK_SAFE_MAX_SECTORS	= 255,
1381 	BLK_DEF_MAX_SECTORS	= 2560,
1382 	BLK_MAX_SEGMENT_SIZE	= 65536,
1383 	BLK_SEG_BOUNDARY_MASK	= 0xFFFFFFFFUL,
1384 };
1385 
1386 static inline unsigned long queue_segment_boundary(const struct request_queue *q)
1387 {
1388 	return q->limits.seg_boundary_mask;
1389 }
1390 
1391 static inline unsigned long queue_virt_boundary(const struct request_queue *q)
1392 {
1393 	return q->limits.virt_boundary_mask;
1394 }
1395 
1396 static inline unsigned int queue_max_sectors(const struct request_queue *q)
1397 {
1398 	return q->limits.max_sectors;
1399 }
1400 
1401 static inline unsigned int queue_max_hw_sectors(const struct request_queue *q)
1402 {
1403 	return q->limits.max_hw_sectors;
1404 }
1405 
1406 static inline unsigned short queue_max_segments(const struct request_queue *q)
1407 {
1408 	return q->limits.max_segments;
1409 }
1410 
1411 static inline unsigned short queue_max_discard_segments(const struct request_queue *q)
1412 {
1413 	return q->limits.max_discard_segments;
1414 }
1415 
1416 static inline unsigned int queue_max_segment_size(const struct request_queue *q)
1417 {
1418 	return q->limits.max_segment_size;
1419 }
1420 
1421 static inline unsigned int queue_max_zone_append_sectors(const struct request_queue *q)
1422 {
1423 
1424 	const struct queue_limits *l = &q->limits;
1425 
1426 	return min(l->max_zone_append_sectors, l->max_sectors);
1427 }
1428 
1429 static inline unsigned queue_logical_block_size(const struct request_queue *q)
1430 {
1431 	int retval = 512;
1432 
1433 	if (q && q->limits.logical_block_size)
1434 		retval = q->limits.logical_block_size;
1435 
1436 	return retval;
1437 }
1438 
1439 static inline unsigned int bdev_logical_block_size(struct block_device *bdev)
1440 {
1441 	return queue_logical_block_size(bdev_get_queue(bdev));
1442 }
1443 
1444 static inline unsigned int queue_physical_block_size(const struct request_queue *q)
1445 {
1446 	return q->limits.physical_block_size;
1447 }
1448 
1449 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1450 {
1451 	return queue_physical_block_size(bdev_get_queue(bdev));
1452 }
1453 
1454 static inline unsigned int queue_io_min(const struct request_queue *q)
1455 {
1456 	return q->limits.io_min;
1457 }
1458 
1459 static inline int bdev_io_min(struct block_device *bdev)
1460 {
1461 	return queue_io_min(bdev_get_queue(bdev));
1462 }
1463 
1464 static inline unsigned int queue_io_opt(const struct request_queue *q)
1465 {
1466 	return q->limits.io_opt;
1467 }
1468 
1469 static inline int bdev_io_opt(struct block_device *bdev)
1470 {
1471 	return queue_io_opt(bdev_get_queue(bdev));
1472 }
1473 
1474 static inline unsigned int
1475 queue_zone_write_granularity(const struct request_queue *q)
1476 {
1477 	return q->limits.zone_write_granularity;
1478 }
1479 
1480 static inline unsigned int
1481 bdev_zone_write_granularity(struct block_device *bdev)
1482 {
1483 	return queue_zone_write_granularity(bdev_get_queue(bdev));
1484 }
1485 
1486 static inline int queue_alignment_offset(const struct request_queue *q)
1487 {
1488 	if (q->limits.misaligned)
1489 		return -1;
1490 
1491 	return q->limits.alignment_offset;
1492 }
1493 
1494 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1495 {
1496 	unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1497 	unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1498 		<< SECTOR_SHIFT;
1499 
1500 	return (granularity + lim->alignment_offset - alignment) % granularity;
1501 }
1502 
1503 static inline int bdev_alignment_offset(struct block_device *bdev)
1504 {
1505 	struct request_queue *q = bdev_get_queue(bdev);
1506 
1507 	if (q->limits.misaligned)
1508 		return -1;
1509 	if (bdev_is_partition(bdev))
1510 		return queue_limit_alignment_offset(&q->limits,
1511 				bdev->bd_start_sect);
1512 	return q->limits.alignment_offset;
1513 }
1514 
1515 static inline int queue_discard_alignment(const struct request_queue *q)
1516 {
1517 	if (q->limits.discard_misaligned)
1518 		return -1;
1519 
1520 	return q->limits.discard_alignment;
1521 }
1522 
1523 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1524 {
1525 	unsigned int alignment, granularity, offset;
1526 
1527 	if (!lim->max_discard_sectors)
1528 		return 0;
1529 
1530 	/* Why are these in bytes, not sectors? */
1531 	alignment = lim->discard_alignment >> SECTOR_SHIFT;
1532 	granularity = lim->discard_granularity >> SECTOR_SHIFT;
1533 	if (!granularity)
1534 		return 0;
1535 
1536 	/* Offset of the partition start in 'granularity' sectors */
1537 	offset = sector_div(sector, granularity);
1538 
1539 	/* And why do we do this modulus *again* in blkdev_issue_discard()? */
1540 	offset = (granularity + alignment - offset) % granularity;
1541 
1542 	/* Turn it back into bytes, gaah */
1543 	return offset << SECTOR_SHIFT;
1544 }
1545 
1546 static inline int bdev_discard_alignment(struct block_device *bdev)
1547 {
1548 	struct request_queue *q = bdev_get_queue(bdev);
1549 
1550 	if (bdev_is_partition(bdev))
1551 		return queue_limit_discard_alignment(&q->limits,
1552 				bdev->bd_start_sect);
1553 	return q->limits.discard_alignment;
1554 }
1555 
1556 static inline unsigned int bdev_write_same(struct block_device *bdev)
1557 {
1558 	struct request_queue *q = bdev_get_queue(bdev);
1559 
1560 	if (q)
1561 		return q->limits.max_write_same_sectors;
1562 
1563 	return 0;
1564 }
1565 
1566 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
1567 {
1568 	struct request_queue *q = bdev_get_queue(bdev);
1569 
1570 	if (q)
1571 		return q->limits.max_write_zeroes_sectors;
1572 
1573 	return 0;
1574 }
1575 
1576 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
1577 {
1578 	struct request_queue *q = bdev_get_queue(bdev);
1579 
1580 	if (q)
1581 		return blk_queue_zoned_model(q);
1582 
1583 	return BLK_ZONED_NONE;
1584 }
1585 
1586 static inline bool bdev_is_zoned(struct block_device *bdev)
1587 {
1588 	struct request_queue *q = bdev_get_queue(bdev);
1589 
1590 	if (q)
1591 		return blk_queue_is_zoned(q);
1592 
1593 	return false;
1594 }
1595 
1596 static inline sector_t bdev_zone_sectors(struct block_device *bdev)
1597 {
1598 	struct request_queue *q = bdev_get_queue(bdev);
1599 
1600 	if (q)
1601 		return blk_queue_zone_sectors(q);
1602 	return 0;
1603 }
1604 
1605 static inline unsigned int bdev_max_open_zones(struct block_device *bdev)
1606 {
1607 	struct request_queue *q = bdev_get_queue(bdev);
1608 
1609 	if (q)
1610 		return queue_max_open_zones(q);
1611 	return 0;
1612 }
1613 
1614 static inline unsigned int bdev_max_active_zones(struct block_device *bdev)
1615 {
1616 	struct request_queue *q = bdev_get_queue(bdev);
1617 
1618 	if (q)
1619 		return queue_max_active_zones(q);
1620 	return 0;
1621 }
1622 
1623 static inline int queue_dma_alignment(const struct request_queue *q)
1624 {
1625 	return q ? q->dma_alignment : 511;
1626 }
1627 
1628 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1629 				 unsigned int len)
1630 {
1631 	unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1632 	return !(addr & alignment) && !(len & alignment);
1633 }
1634 
1635 /* assumes size > 256 */
1636 static inline unsigned int blksize_bits(unsigned int size)
1637 {
1638 	unsigned int bits = 8;
1639 	do {
1640 		bits++;
1641 		size >>= 1;
1642 	} while (size > 256);
1643 	return bits;
1644 }
1645 
1646 static inline unsigned int block_size(struct block_device *bdev)
1647 {
1648 	return 1 << bdev->bd_inode->i_blkbits;
1649 }
1650 
1651 int kblockd_schedule_work(struct work_struct *work);
1652 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1653 
1654 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1655 	MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1656 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1657 	MODULE_ALIAS("block-major-" __stringify(major) "-*")
1658 
1659 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1660 
1661 enum blk_integrity_flags {
1662 	BLK_INTEGRITY_VERIFY		= 1 << 0,
1663 	BLK_INTEGRITY_GENERATE		= 1 << 1,
1664 	BLK_INTEGRITY_DEVICE_CAPABLE	= 1 << 2,
1665 	BLK_INTEGRITY_IP_CHECKSUM	= 1 << 3,
1666 };
1667 
1668 struct blk_integrity_iter {
1669 	void			*prot_buf;
1670 	void			*data_buf;
1671 	sector_t		seed;
1672 	unsigned int		data_size;
1673 	unsigned short		interval;
1674 	const char		*disk_name;
1675 };
1676 
1677 typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
1678 typedef void (integrity_prepare_fn) (struct request *);
1679 typedef void (integrity_complete_fn) (struct request *, unsigned int);
1680 
1681 struct blk_integrity_profile {
1682 	integrity_processing_fn		*generate_fn;
1683 	integrity_processing_fn		*verify_fn;
1684 	integrity_prepare_fn		*prepare_fn;
1685 	integrity_complete_fn		*complete_fn;
1686 	const char			*name;
1687 };
1688 
1689 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1690 extern void blk_integrity_unregister(struct gendisk *);
1691 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1692 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1693 				   struct scatterlist *);
1694 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1695 
1696 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1697 {
1698 	struct blk_integrity *bi = &disk->queue->integrity;
1699 
1700 	if (!bi->profile)
1701 		return NULL;
1702 
1703 	return bi;
1704 }
1705 
1706 static inline
1707 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1708 {
1709 	return blk_get_integrity(bdev->bd_disk);
1710 }
1711 
1712 static inline bool
1713 blk_integrity_queue_supports_integrity(struct request_queue *q)
1714 {
1715 	return q->integrity.profile;
1716 }
1717 
1718 static inline bool blk_integrity_rq(struct request *rq)
1719 {
1720 	return rq->cmd_flags & REQ_INTEGRITY;
1721 }
1722 
1723 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1724 						    unsigned int segs)
1725 {
1726 	q->limits.max_integrity_segments = segs;
1727 }
1728 
1729 static inline unsigned short
1730 queue_max_integrity_segments(const struct request_queue *q)
1731 {
1732 	return q->limits.max_integrity_segments;
1733 }
1734 
1735 /**
1736  * bio_integrity_intervals - Return number of integrity intervals for a bio
1737  * @bi:		blk_integrity profile for device
1738  * @sectors:	Size of the bio in 512-byte sectors
1739  *
1740  * Description: The block layer calculates everything in 512 byte
1741  * sectors but integrity metadata is done in terms of the data integrity
1742  * interval size of the storage device.  Convert the block layer sectors
1743  * to the appropriate number of integrity intervals.
1744  */
1745 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1746 						   unsigned int sectors)
1747 {
1748 	return sectors >> (bi->interval_exp - 9);
1749 }
1750 
1751 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1752 					       unsigned int sectors)
1753 {
1754 	return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
1755 }
1756 
1757 /*
1758  * Return the first bvec that contains integrity data.  Only drivers that are
1759  * limited to a single integrity segment should use this helper.
1760  */
1761 static inline struct bio_vec *rq_integrity_vec(struct request *rq)
1762 {
1763 	if (WARN_ON_ONCE(queue_max_integrity_segments(rq->q) > 1))
1764 		return NULL;
1765 	return rq->bio->bi_integrity->bip_vec;
1766 }
1767 
1768 #else /* CONFIG_BLK_DEV_INTEGRITY */
1769 
1770 struct bio;
1771 struct block_device;
1772 struct gendisk;
1773 struct blk_integrity;
1774 
1775 static inline int blk_integrity_rq(struct request *rq)
1776 {
1777 	return 0;
1778 }
1779 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1780 					    struct bio *b)
1781 {
1782 	return 0;
1783 }
1784 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1785 					  struct bio *b,
1786 					  struct scatterlist *s)
1787 {
1788 	return 0;
1789 }
1790 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1791 {
1792 	return NULL;
1793 }
1794 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1795 {
1796 	return NULL;
1797 }
1798 static inline bool
1799 blk_integrity_queue_supports_integrity(struct request_queue *q)
1800 {
1801 	return false;
1802 }
1803 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1804 {
1805 	return 0;
1806 }
1807 static inline void blk_integrity_register(struct gendisk *d,
1808 					 struct blk_integrity *b)
1809 {
1810 }
1811 static inline void blk_integrity_unregister(struct gendisk *d)
1812 {
1813 }
1814 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1815 						    unsigned int segs)
1816 {
1817 }
1818 static inline unsigned short queue_max_integrity_segments(const struct request_queue *q)
1819 {
1820 	return 0;
1821 }
1822 
1823 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1824 						   unsigned int sectors)
1825 {
1826 	return 0;
1827 }
1828 
1829 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1830 					       unsigned int sectors)
1831 {
1832 	return 0;
1833 }
1834 
1835 static inline struct bio_vec *rq_integrity_vec(struct request *rq)
1836 {
1837 	return NULL;
1838 }
1839 
1840 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1841 
1842 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
1843 
1844 bool blk_ksm_register(struct blk_keyslot_manager *ksm, struct request_queue *q);
1845 
1846 void blk_ksm_unregister(struct request_queue *q);
1847 
1848 #else /* CONFIG_BLK_INLINE_ENCRYPTION */
1849 
1850 static inline bool blk_ksm_register(struct blk_keyslot_manager *ksm,
1851 				    struct request_queue *q)
1852 {
1853 	return true;
1854 }
1855 
1856 static inline void blk_ksm_unregister(struct request_queue *q) { }
1857 
1858 #endif /* CONFIG_BLK_INLINE_ENCRYPTION */
1859 
1860 
1861 struct block_device_operations {
1862 	blk_qc_t (*submit_bio) (struct bio *bio);
1863 	int (*open) (struct block_device *, fmode_t);
1864 	void (*release) (struct gendisk *, fmode_t);
1865 	int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
1866 	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1867 	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1868 	unsigned int (*check_events) (struct gendisk *disk,
1869 				      unsigned int clearing);
1870 	void (*unlock_native_capacity) (struct gendisk *);
1871 	int (*revalidate_disk) (struct gendisk *);
1872 	int (*getgeo)(struct block_device *, struct hd_geometry *);
1873 	int (*set_read_only)(struct block_device *bdev, bool ro);
1874 	/* this callback is with swap_lock and sometimes page table lock held */
1875 	void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1876 	int (*report_zones)(struct gendisk *, sector_t sector,
1877 			unsigned int nr_zones, report_zones_cb cb, void *data);
1878 	char *(*devnode)(struct gendisk *disk, umode_t *mode);
1879 	struct module *owner;
1880 	const struct pr_ops *pr_ops;
1881 };
1882 
1883 #ifdef CONFIG_COMPAT
1884 extern int blkdev_compat_ptr_ioctl(struct block_device *, fmode_t,
1885 				      unsigned int, unsigned long);
1886 #else
1887 #define blkdev_compat_ptr_ioctl NULL
1888 #endif
1889 
1890 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1891 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1892 						struct writeback_control *);
1893 
1894 #ifdef CONFIG_BLK_DEV_ZONED
1895 bool blk_req_needs_zone_write_lock(struct request *rq);
1896 bool blk_req_zone_write_trylock(struct request *rq);
1897 void __blk_req_zone_write_lock(struct request *rq);
1898 void __blk_req_zone_write_unlock(struct request *rq);
1899 
1900 static inline void blk_req_zone_write_lock(struct request *rq)
1901 {
1902 	if (blk_req_needs_zone_write_lock(rq))
1903 		__blk_req_zone_write_lock(rq);
1904 }
1905 
1906 static inline void blk_req_zone_write_unlock(struct request *rq)
1907 {
1908 	if (rq->rq_flags & RQF_ZONE_WRITE_LOCKED)
1909 		__blk_req_zone_write_unlock(rq);
1910 }
1911 
1912 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1913 {
1914 	return rq->q->seq_zones_wlock &&
1915 		test_bit(blk_rq_zone_no(rq), rq->q->seq_zones_wlock);
1916 }
1917 
1918 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1919 {
1920 	if (!blk_req_needs_zone_write_lock(rq))
1921 		return true;
1922 	return !blk_req_zone_is_write_locked(rq);
1923 }
1924 #else
1925 static inline bool blk_req_needs_zone_write_lock(struct request *rq)
1926 {
1927 	return false;
1928 }
1929 
1930 static inline void blk_req_zone_write_lock(struct request *rq)
1931 {
1932 }
1933 
1934 static inline void blk_req_zone_write_unlock(struct request *rq)
1935 {
1936 }
1937 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1938 {
1939 	return false;
1940 }
1941 
1942 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1943 {
1944 	return true;
1945 }
1946 #endif /* CONFIG_BLK_DEV_ZONED */
1947 
1948 static inline void blk_wake_io_task(struct task_struct *waiter)
1949 {
1950 	/*
1951 	 * If we're polling, the task itself is doing the completions. For
1952 	 * that case, we don't need to signal a wakeup, it's enough to just
1953 	 * mark us as RUNNING.
1954 	 */
1955 	if (waiter == current)
1956 		__set_current_state(TASK_RUNNING);
1957 	else
1958 		wake_up_process(waiter);
1959 }
1960 
1961 unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,
1962 		unsigned int op);
1963 void disk_end_io_acct(struct gendisk *disk, unsigned int op,
1964 		unsigned long start_time);
1965 
1966 unsigned long bio_start_io_acct(struct bio *bio);
1967 void bio_end_io_acct_remapped(struct bio *bio, unsigned long start_time,
1968 		struct block_device *orig_bdev);
1969 
1970 /**
1971  * bio_end_io_acct - end I/O accounting for bio based drivers
1972  * @bio:	bio to end account for
1973  * @start:	start time returned by bio_start_io_acct()
1974  */
1975 static inline void bio_end_io_acct(struct bio *bio, unsigned long start_time)
1976 {
1977 	return bio_end_io_acct_remapped(bio, start_time, bio->bi_bdev);
1978 }
1979 
1980 int bdev_read_only(struct block_device *bdev);
1981 int set_blocksize(struct block_device *bdev, int size);
1982 
1983 const char *bdevname(struct block_device *bdev, char *buffer);
1984 int lookup_bdev(const char *pathname, dev_t *dev);
1985 
1986 void blkdev_show(struct seq_file *seqf, off_t offset);
1987 
1988 #define BDEVNAME_SIZE	32	/* Largest string for a blockdev identifier */
1989 #define BDEVT_SIZE	10	/* Largest string for MAJ:MIN for blkdev */
1990 #ifdef CONFIG_BLOCK
1991 #define BLKDEV_MAJOR_MAX	512
1992 #else
1993 #define BLKDEV_MAJOR_MAX	0
1994 #endif
1995 
1996 struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
1997 		void *holder);
1998 struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, void *holder);
1999 int bd_prepare_to_claim(struct block_device *bdev, void *holder);
2000 void bd_abort_claiming(struct block_device *bdev, void *holder);
2001 void blkdev_put(struct block_device *bdev, fmode_t mode);
2002 
2003 /* just for blk-cgroup, don't use elsewhere */
2004 struct block_device *blkdev_get_no_open(dev_t dev);
2005 void blkdev_put_no_open(struct block_device *bdev);
2006 
2007 struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
2008 void bdev_add(struct block_device *bdev, dev_t dev);
2009 struct block_device *I_BDEV(struct inode *inode);
2010 struct block_device *bdgrab(struct block_device *bdev);
2011 void bdput(struct block_device *);
2012 int truncate_bdev_range(struct block_device *bdev, fmode_t mode, loff_t lstart,
2013 		loff_t lend);
2014 
2015 #ifdef CONFIG_BLOCK
2016 void invalidate_bdev(struct block_device *bdev);
2017 int sync_blockdev(struct block_device *bdev);
2018 #else
2019 static inline void invalidate_bdev(struct block_device *bdev)
2020 {
2021 }
2022 static inline int sync_blockdev(struct block_device *bdev)
2023 {
2024 	return 0;
2025 }
2026 #endif
2027 int fsync_bdev(struct block_device *bdev);
2028 
2029 int freeze_bdev(struct block_device *bdev);
2030 int thaw_bdev(struct block_device *bdev);
2031 
2032 #endif /* _LINUX_BLKDEV_H */
2033