xref: /linux-6.15/include/linux/blkdev.h (revision efc5b2e7)
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/timer.h>
12 #include <linux/workqueue.h>
13 #include <linux/pagemap.h>
14 #include <linux/backing-dev-defs.h>
15 #include <linux/wait.h>
16 #include <linux/mempool.h>
17 #include <linux/pfn.h>
18 #include <linux/bio.h>
19 #include <linux/stringify.h>
20 #include <linux/gfp.h>
21 #include <linux/bsg.h>
22 #include <linux/smp.h>
23 #include <linux/rcupdate.h>
24 #include <linux/percpu-refcount.h>
25 #include <linux/scatterlist.h>
26 #include <linux/blkzoned.h>
27 
28 struct module;
29 struct scsi_ioctl_command;
30 
31 struct request_queue;
32 struct elevator_queue;
33 struct blk_trace;
34 struct request;
35 struct sg_io_hdr;
36 struct bsg_job;
37 struct blkcg_gq;
38 struct blk_flush_queue;
39 struct pr_ops;
40 struct rq_qos;
41 struct blk_queue_stats;
42 struct blk_stat_callback;
43 struct blk_keyslot_manager;
44 
45 #define BLKDEV_MIN_RQ	4
46 #define BLKDEV_MAX_RQ	128	/* Default maximum */
47 
48 /* Must be consistent with blk_mq_poll_stats_bkt() */
49 #define BLK_MQ_POLL_STATS_BKTS 16
50 
51 /* Doing classic polling */
52 #define BLK_MQ_POLL_CLASSIC -1
53 
54 /*
55  * Maximum number of blkcg policies allowed to be registered concurrently.
56  * Defined here to simplify include dependency.
57  */
58 #define BLKCG_MAX_POLS		5
59 
60 typedef void (rq_end_io_fn)(struct request *, blk_status_t);
61 
62 /*
63  * request flags */
64 typedef __u32 __bitwise req_flags_t;
65 
66 /* elevator knows about this request */
67 #define RQF_SORTED		((__force req_flags_t)(1 << 0))
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 /* set for "ide_preempt" requests and also for requests for which the SCSI
81    "quiesce" state must be ignored. */
82 #define RQF_PREEMPT		((__force req_flags_t)(1 << 8))
83 /* vaguely specified driver internal error.  Ignored by the block layer */
84 #define RQF_FAILED		((__force req_flags_t)(1 << 10))
85 /* don't warn about errors */
86 #define RQF_QUIET		((__force req_flags_t)(1 << 11))
87 /* elevator private data attached */
88 #define RQF_ELVPRIV		((__force req_flags_t)(1 << 12))
89 /* account into disk and partition IO statistics */
90 #define RQF_IO_STAT		((__force req_flags_t)(1 << 13))
91 /* request came from our alloc pool */
92 #define RQF_ALLOCED		((__force req_flags_t)(1 << 14))
93 /* runtime pm request */
94 #define RQF_PM			((__force req_flags_t)(1 << 15))
95 /* on IO scheduler merge hash */
96 #define RQF_HASHED		((__force req_flags_t)(1 << 16))
97 /* track IO completion time */
98 #define RQF_STATS		((__force req_flags_t)(1 << 17))
99 /* Look at ->special_vec for the actual data payload instead of the
100    bio chain. */
101 #define RQF_SPECIAL_PAYLOAD	((__force req_flags_t)(1 << 18))
102 /* The per-zone write lock is held for this request */
103 #define RQF_ZONE_WRITE_LOCKED	((__force req_flags_t)(1 << 19))
104 /* already slept for hybrid poll */
105 #define RQF_MQ_POLL_SLEPT	((__force req_flags_t)(1 << 20))
106 /* ->timeout has been called, don't expire again */
107 #define RQF_TIMED_OUT		((__force req_flags_t)(1 << 21))
108 
109 /* flags that prevent us from merging requests: */
110 #define RQF_NOMERGE_FLAGS \
111 	(RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD)
112 
113 /*
114  * Request state for blk-mq.
115  */
116 enum mq_rq_state {
117 	MQ_RQ_IDLE		= 0,
118 	MQ_RQ_IN_FLIGHT		= 1,
119 	MQ_RQ_COMPLETE		= 2,
120 };
121 
122 /*
123  * Try to put the fields that are referenced together in the same cacheline.
124  *
125  * If you modify this structure, make sure to update blk_rq_init() and
126  * especially blk_mq_rq_ctx_init() to take care of the added fields.
127  */
128 struct request {
129 	struct request_queue *q;
130 	struct blk_mq_ctx *mq_ctx;
131 	struct blk_mq_hw_ctx *mq_hctx;
132 
133 	unsigned int cmd_flags;		/* op and common flags */
134 	req_flags_t rq_flags;
135 
136 	int tag;
137 	int internal_tag;
138 
139 	/* the following two fields are internal, NEVER access directly */
140 	unsigned int __data_len;	/* total data len */
141 	sector_t __sector;		/* sector cursor */
142 
143 	struct bio *bio;
144 	struct bio *biotail;
145 
146 	struct list_head queuelist;
147 
148 	/*
149 	 * The hash is used inside the scheduler, and killed once the
150 	 * request reaches the dispatch list. The ipi_list is only used
151 	 * to queue the request for softirq completion, which is long
152 	 * after the request has been unhashed (and even removed from
153 	 * the dispatch list).
154 	 */
155 	union {
156 		struct hlist_node hash;	/* merge hash */
157 		struct list_head ipi_list;
158 	};
159 
160 	/*
161 	 * The rb_node is only used inside the io scheduler, requests
162 	 * are pruned when moved to the dispatch queue. So let the
163 	 * completion_data share space with the rb_node.
164 	 */
165 	union {
166 		struct rb_node rb_node;	/* sort/lookup */
167 		struct bio_vec special_vec;
168 		void *completion_data;
169 		int error_count; /* for legacy drivers, don't use */
170 	};
171 
172 	/*
173 	 * Three pointers are available for the IO schedulers, if they need
174 	 * more they have to dynamically allocate it.  Flush requests are
175 	 * never put on the IO scheduler. So let the flush fields share
176 	 * space with the elevator data.
177 	 */
178 	union {
179 		struct {
180 			struct io_cq		*icq;
181 			void			*priv[2];
182 		} elv;
183 
184 		struct {
185 			unsigned int		seq;
186 			struct list_head	list;
187 			rq_end_io_fn		*saved_end_io;
188 		} flush;
189 	};
190 
191 	struct gendisk *rq_disk;
192 	struct hd_struct *part;
193 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
194 	/* Time that the first bio started allocating this request. */
195 	u64 alloc_time_ns;
196 #endif
197 	/* Time that this request was allocated for this IO. */
198 	u64 start_time_ns;
199 	/* Time that I/O was submitted to the device. */
200 	u64 io_start_time_ns;
201 
202 #ifdef CONFIG_BLK_WBT
203 	unsigned short wbt_flags;
204 #endif
205 	/*
206 	 * rq sectors used for blk stats. It has the same value
207 	 * with blk_rq_sectors(rq), except that it never be zeroed
208 	 * by completion.
209 	 */
210 	unsigned short stats_sectors;
211 
212 	/*
213 	 * Number of scatter-gather DMA addr+len pairs after
214 	 * physical address coalescing is performed.
215 	 */
216 	unsigned short nr_phys_segments;
217 
218 #if defined(CONFIG_BLK_DEV_INTEGRITY)
219 	unsigned short nr_integrity_segments;
220 #endif
221 
222 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
223 	struct bio_crypt_ctx *crypt_ctx;
224 	struct blk_ksm_keyslot *crypt_keyslot;
225 #endif
226 
227 	unsigned short write_hint;
228 	unsigned short ioprio;
229 
230 	enum mq_rq_state state;
231 	refcount_t ref;
232 
233 	unsigned int timeout;
234 	unsigned long deadline;
235 
236 	union {
237 		struct __call_single_data csd;
238 		u64 fifo_time;
239 	};
240 
241 	/*
242 	 * completion callback.
243 	 */
244 	rq_end_io_fn *end_io;
245 	void *end_io_data;
246 };
247 
248 static inline bool blk_op_is_scsi(unsigned int op)
249 {
250 	return op == REQ_OP_SCSI_IN || op == REQ_OP_SCSI_OUT;
251 }
252 
253 static inline bool blk_op_is_private(unsigned int op)
254 {
255 	return op == REQ_OP_DRV_IN || op == REQ_OP_DRV_OUT;
256 }
257 
258 static inline bool blk_rq_is_scsi(struct request *rq)
259 {
260 	return blk_op_is_scsi(req_op(rq));
261 }
262 
263 static inline bool blk_rq_is_private(struct request *rq)
264 {
265 	return blk_op_is_private(req_op(rq));
266 }
267 
268 static inline bool blk_rq_is_passthrough(struct request *rq)
269 {
270 	return blk_rq_is_scsi(rq) || blk_rq_is_private(rq);
271 }
272 
273 static inline bool bio_is_passthrough(struct bio *bio)
274 {
275 	unsigned op = bio_op(bio);
276 
277 	return blk_op_is_scsi(op) || blk_op_is_private(op);
278 }
279 
280 static inline unsigned short req_get_ioprio(struct request *req)
281 {
282 	return req->ioprio;
283 }
284 
285 #include <linux/elevator.h>
286 
287 struct blk_queue_ctx;
288 
289 struct bio_vec;
290 
291 enum blk_eh_timer_return {
292 	BLK_EH_DONE,		/* drivers has completed the command */
293 	BLK_EH_RESET_TIMER,	/* reset timer and try again */
294 };
295 
296 enum blk_queue_state {
297 	Queue_down,
298 	Queue_up,
299 };
300 
301 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
302 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
303 
304 #define BLK_SCSI_MAX_CMDS	(256)
305 #define BLK_SCSI_CMD_PER_LONG	(BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
306 
307 /*
308  * Zoned block device models (zoned limit).
309  *
310  * Note: This needs to be ordered from the least to the most severe
311  * restrictions for the inheritance in blk_stack_limits() to work.
312  */
313 enum blk_zoned_model {
314 	BLK_ZONED_NONE = 0,	/* Regular block device */
315 	BLK_ZONED_HA,		/* Host-aware zoned block device */
316 	BLK_ZONED_HM,		/* Host-managed zoned block device */
317 };
318 
319 struct queue_limits {
320 	unsigned long		bounce_pfn;
321 	unsigned long		seg_boundary_mask;
322 	unsigned long		virt_boundary_mask;
323 
324 	unsigned int		max_hw_sectors;
325 	unsigned int		max_dev_sectors;
326 	unsigned int		chunk_sectors;
327 	unsigned int		max_sectors;
328 	unsigned int		max_segment_size;
329 	unsigned int		physical_block_size;
330 	unsigned int		logical_block_size;
331 	unsigned int		alignment_offset;
332 	unsigned int		io_min;
333 	unsigned int		io_opt;
334 	unsigned int		max_discard_sectors;
335 	unsigned int		max_hw_discard_sectors;
336 	unsigned int		max_write_same_sectors;
337 	unsigned int		max_write_zeroes_sectors;
338 	unsigned int		max_zone_append_sectors;
339 	unsigned int		discard_granularity;
340 	unsigned int		discard_alignment;
341 
342 	unsigned short		max_segments;
343 	unsigned short		max_integrity_segments;
344 	unsigned short		max_discard_segments;
345 
346 	unsigned char		misaligned;
347 	unsigned char		discard_misaligned;
348 	unsigned char		raid_partial_stripes_expensive;
349 	enum blk_zoned_model	zoned;
350 };
351 
352 typedef int (*report_zones_cb)(struct blk_zone *zone, unsigned int idx,
353 			       void *data);
354 
355 void blk_queue_set_zoned(struct gendisk *disk, enum blk_zoned_model model);
356 
357 #ifdef CONFIG_BLK_DEV_ZONED
358 
359 #define BLK_ALL_ZONES  ((unsigned int)-1)
360 int blkdev_report_zones(struct block_device *bdev, sector_t sector,
361 			unsigned int nr_zones, report_zones_cb cb, void *data);
362 unsigned int blkdev_nr_zones(struct gendisk *disk);
363 extern int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op,
364 			    sector_t sectors, sector_t nr_sectors,
365 			    gfp_t gfp_mask);
366 int blk_revalidate_disk_zones(struct gendisk *disk,
367 			      void (*update_driver_data)(struct gendisk *disk));
368 
369 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
370 				     unsigned int cmd, unsigned long arg);
371 extern int blkdev_zone_mgmt_ioctl(struct block_device *bdev, fmode_t mode,
372 				  unsigned int cmd, unsigned long arg);
373 
374 #else /* CONFIG_BLK_DEV_ZONED */
375 
376 static inline unsigned int blkdev_nr_zones(struct gendisk *disk)
377 {
378 	return 0;
379 }
380 
381 static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
382 					    fmode_t mode, unsigned int cmd,
383 					    unsigned long arg)
384 {
385 	return -ENOTTY;
386 }
387 
388 static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
389 					 fmode_t mode, unsigned int cmd,
390 					 unsigned long arg)
391 {
392 	return -ENOTTY;
393 }
394 
395 #endif /* CONFIG_BLK_DEV_ZONED */
396 
397 struct request_queue {
398 	struct request		*last_merge;
399 	struct elevator_queue	*elevator;
400 
401 	struct blk_queue_stats	*stats;
402 	struct rq_qos		*rq_qos;
403 
404 	const struct blk_mq_ops	*mq_ops;
405 
406 	/* sw queues */
407 	struct blk_mq_ctx __percpu	*queue_ctx;
408 
409 	unsigned int		queue_depth;
410 
411 	/* hw dispatch queues */
412 	struct blk_mq_hw_ctx	**queue_hw_ctx;
413 	unsigned int		nr_hw_queues;
414 
415 	struct backing_dev_info	*backing_dev_info;
416 
417 	/*
418 	 * The queue owner gets to use this for whatever they like.
419 	 * ll_rw_blk doesn't touch it.
420 	 */
421 	void			*queuedata;
422 
423 	/*
424 	 * various queue flags, see QUEUE_* below
425 	 */
426 	unsigned long		queue_flags;
427 	/*
428 	 * Number of contexts that have called blk_set_pm_only(). If this
429 	 * counter is above zero then only RQF_PM and RQF_PREEMPT requests are
430 	 * processed.
431 	 */
432 	atomic_t		pm_only;
433 
434 	/*
435 	 * ida allocated id for this queue.  Used to index queues from
436 	 * ioctx.
437 	 */
438 	int			id;
439 
440 	/*
441 	 * queue needs bounce pages for pages above this limit
442 	 */
443 	gfp_t			bounce_gfp;
444 
445 	spinlock_t		queue_lock;
446 
447 	/*
448 	 * queue kobject
449 	 */
450 	struct kobject kobj;
451 
452 	/*
453 	 * mq queue kobject
454 	 */
455 	struct kobject *mq_kobj;
456 
457 #ifdef  CONFIG_BLK_DEV_INTEGRITY
458 	struct blk_integrity integrity;
459 #endif	/* CONFIG_BLK_DEV_INTEGRITY */
460 
461 #ifdef CONFIG_PM
462 	struct device		*dev;
463 	int			rpm_status;
464 	unsigned int		nr_pending;
465 #endif
466 
467 	/*
468 	 * queue settings
469 	 */
470 	unsigned long		nr_requests;	/* Max # of requests */
471 
472 	unsigned int		dma_pad_mask;
473 	unsigned int		dma_alignment;
474 
475 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
476 	/* Inline crypto capabilities */
477 	struct blk_keyslot_manager *ksm;
478 #endif
479 
480 	unsigned int		rq_timeout;
481 	int			poll_nsec;
482 
483 	struct blk_stat_callback	*poll_cb;
484 	struct blk_rq_stat	poll_stat[BLK_MQ_POLL_STATS_BKTS];
485 
486 	struct timer_list	timeout;
487 	struct work_struct	timeout_work;
488 
489 	struct list_head	icq_list;
490 #ifdef CONFIG_BLK_CGROUP
491 	DECLARE_BITMAP		(blkcg_pols, BLKCG_MAX_POLS);
492 	struct blkcg_gq		*root_blkg;
493 	struct list_head	blkg_list;
494 #endif
495 
496 	struct queue_limits	limits;
497 
498 	unsigned int		required_elevator_features;
499 
500 #ifdef CONFIG_BLK_DEV_ZONED
501 	/*
502 	 * Zoned block device information for request dispatch control.
503 	 * nr_zones is the total number of zones of the device. This is always
504 	 * 0 for regular block devices. conv_zones_bitmap is a bitmap of nr_zones
505 	 * bits which indicates if a zone is conventional (bit set) or
506 	 * sequential (bit clear). seq_zones_wlock is a bitmap of nr_zones
507 	 * bits which indicates if a zone is write locked, that is, if a write
508 	 * request targeting the zone was dispatched. All three fields are
509 	 * initialized by the low level device driver (e.g. scsi/sd.c).
510 	 * Stacking drivers (device mappers) may or may not initialize
511 	 * these fields.
512 	 *
513 	 * Reads of this information must be protected with blk_queue_enter() /
514 	 * blk_queue_exit(). Modifying this information is only allowed while
515 	 * no requests are being processed. See also blk_mq_freeze_queue() and
516 	 * blk_mq_unfreeze_queue().
517 	 */
518 	unsigned int		nr_zones;
519 	unsigned long		*conv_zones_bitmap;
520 	unsigned long		*seq_zones_wlock;
521 	unsigned int		max_open_zones;
522 	unsigned int		max_active_zones;
523 #endif /* CONFIG_BLK_DEV_ZONED */
524 
525 	/*
526 	 * sg stuff
527 	 */
528 	unsigned int		sg_timeout;
529 	unsigned int		sg_reserved_size;
530 	int			node;
531 	struct mutex		debugfs_mutex;
532 #ifdef CONFIG_BLK_DEV_IO_TRACE
533 	struct blk_trace __rcu	*blk_trace;
534 #endif
535 	/*
536 	 * for flush operations
537 	 */
538 	struct blk_flush_queue	*fq;
539 
540 	struct list_head	requeue_list;
541 	spinlock_t		requeue_lock;
542 	struct delayed_work	requeue_work;
543 
544 	struct mutex		sysfs_lock;
545 	struct mutex		sysfs_dir_lock;
546 
547 	/*
548 	 * for reusing dead hctx instance in case of updating
549 	 * nr_hw_queues
550 	 */
551 	struct list_head	unused_hctx_list;
552 	spinlock_t		unused_hctx_lock;
553 
554 	int			mq_freeze_depth;
555 
556 #if defined(CONFIG_BLK_DEV_BSG)
557 	struct bsg_class_device bsg_dev;
558 #endif
559 
560 #ifdef CONFIG_BLK_DEV_THROTTLING
561 	/* Throttle data */
562 	struct throtl_data *td;
563 #endif
564 	struct rcu_head		rcu_head;
565 	wait_queue_head_t	mq_freeze_wq;
566 	/*
567 	 * Protect concurrent access to q_usage_counter by
568 	 * percpu_ref_kill() and percpu_ref_reinit().
569 	 */
570 	struct mutex		mq_freeze_lock;
571 	struct percpu_ref	q_usage_counter;
572 
573 	struct blk_mq_tag_set	*tag_set;
574 	struct list_head	tag_set_list;
575 	struct bio_set		bio_split;
576 
577 	struct dentry		*debugfs_dir;
578 
579 #ifdef CONFIG_BLK_DEBUG_FS
580 	struct dentry		*sched_debugfs_dir;
581 	struct dentry		*rqos_debugfs_dir;
582 #endif
583 
584 	bool			mq_sysfs_init_done;
585 
586 	size_t			cmd_size;
587 
588 #define BLK_MAX_WRITE_HINTS	5
589 	u64			write_hints[BLK_MAX_WRITE_HINTS];
590 };
591 
592 /* Keep blk_queue_flag_name[] in sync with the definitions below */
593 #define QUEUE_FLAG_STOPPED	0	/* queue is stopped */
594 #define QUEUE_FLAG_DYING	1	/* queue being torn down */
595 #define QUEUE_FLAG_NOMERGES     3	/* disable merge attempts */
596 #define QUEUE_FLAG_SAME_COMP	4	/* complete on same CPU-group */
597 #define QUEUE_FLAG_FAIL_IO	5	/* fake timeout */
598 #define QUEUE_FLAG_NONROT	6	/* non-rotational device (SSD) */
599 #define QUEUE_FLAG_VIRT		QUEUE_FLAG_NONROT /* paravirt device */
600 #define QUEUE_FLAG_IO_STAT	7	/* do disk/partitions IO accounting */
601 #define QUEUE_FLAG_DISCARD	8	/* supports DISCARD */
602 #define QUEUE_FLAG_NOXMERGES	9	/* No extended merges */
603 #define QUEUE_FLAG_ADD_RANDOM	10	/* Contributes to random pool */
604 #define QUEUE_FLAG_SECERASE	11	/* supports secure erase */
605 #define QUEUE_FLAG_SAME_FORCE	12	/* force complete on same CPU */
606 #define QUEUE_FLAG_DEAD		13	/* queue tear-down finished */
607 #define QUEUE_FLAG_INIT_DONE	14	/* queue is initialized */
608 #define QUEUE_FLAG_POLL		16	/* IO polling enabled if set */
609 #define QUEUE_FLAG_WC		17	/* Write back caching */
610 #define QUEUE_FLAG_FUA		18	/* device supports FUA writes */
611 #define QUEUE_FLAG_DAX		19	/* device supports DAX */
612 #define QUEUE_FLAG_STATS	20	/* track IO start and completion times */
613 #define QUEUE_FLAG_POLL_STATS	21	/* collecting stats for hybrid polling */
614 #define QUEUE_FLAG_REGISTERED	22	/* queue has been registered to a disk */
615 #define QUEUE_FLAG_SCSI_PASSTHROUGH 23	/* queue supports SCSI commands */
616 #define QUEUE_FLAG_QUIESCED	24	/* queue has been quiesced */
617 #define QUEUE_FLAG_PCI_P2PDMA	25	/* device supports PCI p2p requests */
618 #define QUEUE_FLAG_ZONE_RESETALL 26	/* supports Zone Reset All */
619 #define QUEUE_FLAG_RQ_ALLOC_TIME 27	/* record rq->alloc_time_ns */
620 
621 #define QUEUE_FLAG_MQ_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
622 				 (1 << QUEUE_FLAG_SAME_COMP))
623 
624 void blk_queue_flag_set(unsigned int flag, struct request_queue *q);
625 void blk_queue_flag_clear(unsigned int flag, struct request_queue *q);
626 bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);
627 
628 #define blk_queue_stopped(q)	test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
629 #define blk_queue_dying(q)	test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
630 #define blk_queue_dead(q)	test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
631 #define blk_queue_init_done(q)	test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
632 #define blk_queue_nomerges(q)	test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
633 #define blk_queue_noxmerges(q)	\
634 	test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
635 #define blk_queue_nonrot(q)	test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
636 #define blk_queue_io_stat(q)	test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
637 #define blk_queue_add_random(q)	test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
638 #define blk_queue_discard(q)	test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
639 #define blk_queue_zone_resetall(q)	\
640 	test_bit(QUEUE_FLAG_ZONE_RESETALL, &(q)->queue_flags)
641 #define blk_queue_secure_erase(q) \
642 	(test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
643 #define blk_queue_dax(q)	test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
644 #define blk_queue_scsi_passthrough(q)	\
645 	test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags)
646 #define blk_queue_pci_p2pdma(q)	\
647 	test_bit(QUEUE_FLAG_PCI_P2PDMA, &(q)->queue_flags)
648 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
649 #define blk_queue_rq_alloc_time(q)	\
650 	test_bit(QUEUE_FLAG_RQ_ALLOC_TIME, &(q)->queue_flags)
651 #else
652 #define blk_queue_rq_alloc_time(q)	false
653 #endif
654 
655 #define blk_noretry_request(rq) \
656 	((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
657 			     REQ_FAILFAST_DRIVER))
658 #define blk_queue_quiesced(q)	test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
659 #define blk_queue_pm_only(q)	atomic_read(&(q)->pm_only)
660 #define blk_queue_fua(q)	test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags)
661 #define blk_queue_registered(q)	test_bit(QUEUE_FLAG_REGISTERED, &(q)->queue_flags)
662 
663 extern void blk_set_pm_only(struct request_queue *q);
664 extern void blk_clear_pm_only(struct request_queue *q);
665 
666 static inline bool blk_account_rq(struct request *rq)
667 {
668 	return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq);
669 }
670 
671 #define list_entry_rq(ptr)	list_entry((ptr), struct request, queuelist)
672 
673 #define rq_data_dir(rq)		(op_is_write(req_op(rq)) ? WRITE : READ)
674 
675 #define rq_dma_dir(rq) \
676 	(op_is_write(req_op(rq)) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
677 
678 #define dma_map_bvec(dev, bv, dir, attrs) \
679 	dma_map_page_attrs(dev, (bv)->bv_page, (bv)->bv_offset, (bv)->bv_len, \
680 	(dir), (attrs))
681 
682 static inline bool queue_is_mq(struct request_queue *q)
683 {
684 	return q->mq_ops;
685 }
686 
687 static inline enum blk_zoned_model
688 blk_queue_zoned_model(struct request_queue *q)
689 {
690 	return q->limits.zoned;
691 }
692 
693 static inline bool blk_queue_is_zoned(struct request_queue *q)
694 {
695 	switch (blk_queue_zoned_model(q)) {
696 	case BLK_ZONED_HA:
697 	case BLK_ZONED_HM:
698 		return true;
699 	default:
700 		return false;
701 	}
702 }
703 
704 static inline sector_t blk_queue_zone_sectors(struct request_queue *q)
705 {
706 	return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0;
707 }
708 
709 #ifdef CONFIG_BLK_DEV_ZONED
710 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
711 {
712 	return blk_queue_is_zoned(q) ? q->nr_zones : 0;
713 }
714 
715 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
716 					     sector_t sector)
717 {
718 	if (!blk_queue_is_zoned(q))
719 		return 0;
720 	return sector >> ilog2(q->limits.chunk_sectors);
721 }
722 
723 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
724 					 sector_t sector)
725 {
726 	if (!blk_queue_is_zoned(q))
727 		return false;
728 	if (!q->conv_zones_bitmap)
729 		return true;
730 	return !test_bit(blk_queue_zone_no(q, sector), q->conv_zones_bitmap);
731 }
732 
733 static inline void blk_queue_max_open_zones(struct request_queue *q,
734 		unsigned int max_open_zones)
735 {
736 	q->max_open_zones = max_open_zones;
737 }
738 
739 static inline unsigned int queue_max_open_zones(const struct request_queue *q)
740 {
741 	return q->max_open_zones;
742 }
743 
744 static inline void blk_queue_max_active_zones(struct request_queue *q,
745 		unsigned int max_active_zones)
746 {
747 	q->max_active_zones = max_active_zones;
748 }
749 
750 static inline unsigned int queue_max_active_zones(const struct request_queue *q)
751 {
752 	return q->max_active_zones;
753 }
754 #else /* CONFIG_BLK_DEV_ZONED */
755 static inline unsigned int blk_queue_nr_zones(struct request_queue *q)
756 {
757 	return 0;
758 }
759 static inline bool blk_queue_zone_is_seq(struct request_queue *q,
760 					 sector_t sector)
761 {
762 	return false;
763 }
764 static inline unsigned int blk_queue_zone_no(struct request_queue *q,
765 					     sector_t sector)
766 {
767 	return 0;
768 }
769 static inline unsigned int queue_max_open_zones(const struct request_queue *q)
770 {
771 	return 0;
772 }
773 static inline unsigned int queue_max_active_zones(const struct request_queue *q)
774 {
775 	return 0;
776 }
777 #endif /* CONFIG_BLK_DEV_ZONED */
778 
779 static inline bool rq_is_sync(struct request *rq)
780 {
781 	return op_is_sync(rq->cmd_flags);
782 }
783 
784 static inline bool rq_mergeable(struct request *rq)
785 {
786 	if (blk_rq_is_passthrough(rq))
787 		return false;
788 
789 	if (req_op(rq) == REQ_OP_FLUSH)
790 		return false;
791 
792 	if (req_op(rq) == REQ_OP_WRITE_ZEROES)
793 		return false;
794 
795 	if (req_op(rq) == REQ_OP_ZONE_APPEND)
796 		return false;
797 
798 	if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
799 		return false;
800 	if (rq->rq_flags & RQF_NOMERGE_FLAGS)
801 		return false;
802 
803 	return true;
804 }
805 
806 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
807 {
808 	if (bio_page(a) == bio_page(b) &&
809 	    bio_offset(a) == bio_offset(b))
810 		return true;
811 
812 	return false;
813 }
814 
815 static inline unsigned int blk_queue_depth(struct request_queue *q)
816 {
817 	if (q->queue_depth)
818 		return q->queue_depth;
819 
820 	return q->nr_requests;
821 }
822 
823 extern unsigned long blk_max_low_pfn, blk_max_pfn;
824 
825 /*
826  * standard bounce addresses:
827  *
828  * BLK_BOUNCE_HIGH	: bounce all highmem pages
829  * BLK_BOUNCE_ANY	: don't bounce anything
830  * BLK_BOUNCE_ISA	: bounce pages above ISA DMA boundary
831  */
832 
833 #if BITS_PER_LONG == 32
834 #define BLK_BOUNCE_HIGH		((u64)blk_max_low_pfn << PAGE_SHIFT)
835 #else
836 #define BLK_BOUNCE_HIGH		-1ULL
837 #endif
838 #define BLK_BOUNCE_ANY		(-1ULL)
839 #define BLK_BOUNCE_ISA		(DMA_BIT_MASK(24))
840 
841 /*
842  * default timeout for SG_IO if none specified
843  */
844 #define BLK_DEFAULT_SG_TIMEOUT	(60 * HZ)
845 #define BLK_MIN_SG_TIMEOUT	(7 * HZ)
846 
847 struct rq_map_data {
848 	struct page **pages;
849 	int page_order;
850 	int nr_entries;
851 	unsigned long offset;
852 	int null_mapped;
853 	int from_user;
854 };
855 
856 struct req_iterator {
857 	struct bvec_iter iter;
858 	struct bio *bio;
859 };
860 
861 /* This should not be used directly - use rq_for_each_segment */
862 #define for_each_bio(_bio)		\
863 	for (; _bio; _bio = _bio->bi_next)
864 #define __rq_for_each_bio(_bio, rq)	\
865 	if ((rq->bio))			\
866 		for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
867 
868 #define rq_for_each_segment(bvl, _rq, _iter)			\
869 	__rq_for_each_bio(_iter.bio, _rq)			\
870 		bio_for_each_segment(bvl, _iter.bio, _iter.iter)
871 
872 #define rq_for_each_bvec(bvl, _rq, _iter)			\
873 	__rq_for_each_bio(_iter.bio, _rq)			\
874 		bio_for_each_bvec(bvl, _iter.bio, _iter.iter)
875 
876 #define rq_iter_last(bvec, _iter)				\
877 		(_iter.bio->bi_next == NULL &&			\
878 		 bio_iter_last(bvec, _iter.iter))
879 
880 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
881 # error	"You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
882 #endif
883 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
884 extern void rq_flush_dcache_pages(struct request *rq);
885 #else
886 static inline void rq_flush_dcache_pages(struct request *rq)
887 {
888 }
889 #endif
890 
891 extern int blk_register_queue(struct gendisk *disk);
892 extern void blk_unregister_queue(struct gendisk *disk);
893 blk_qc_t submit_bio_noacct(struct bio *bio);
894 extern void blk_rq_init(struct request_queue *q, struct request *rq);
895 extern void blk_put_request(struct request *);
896 extern struct request *blk_get_request(struct request_queue *, unsigned int op,
897 				       blk_mq_req_flags_t flags);
898 extern int blk_lld_busy(struct request_queue *q);
899 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
900 			     struct bio_set *bs, gfp_t gfp_mask,
901 			     int (*bio_ctr)(struct bio *, struct bio *, void *),
902 			     void *data);
903 extern void blk_rq_unprep_clone(struct request *rq);
904 extern blk_status_t blk_insert_cloned_request(struct request_queue *q,
905 				     struct request *rq);
906 extern int blk_rq_append_bio(struct request *rq, struct bio **bio);
907 extern void blk_queue_split(struct bio **);
908 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
909 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
910 			      unsigned int, void __user *);
911 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
912 			  unsigned int, void __user *);
913 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
914 			 struct scsi_ioctl_command __user *);
915 extern int get_sg_io_hdr(struct sg_io_hdr *hdr, const void __user *argp);
916 extern int put_sg_io_hdr(const struct sg_io_hdr *hdr, void __user *argp);
917 
918 extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
919 extern void blk_queue_exit(struct request_queue *q);
920 extern void blk_sync_queue(struct request_queue *q);
921 extern int blk_rq_map_user(struct request_queue *, struct request *,
922 			   struct rq_map_data *, void __user *, unsigned long,
923 			   gfp_t);
924 extern int blk_rq_unmap_user(struct bio *);
925 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
926 extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
927 			       struct rq_map_data *, const struct iov_iter *,
928 			       gfp_t);
929 extern void blk_execute_rq(struct request_queue *, struct gendisk *,
930 			  struct request *, int);
931 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
932 				  struct request *, int, rq_end_io_fn *);
933 
934 /* Helper to convert REQ_OP_XXX to its string format XXX */
935 extern const char *blk_op_str(unsigned int op);
936 
937 int blk_status_to_errno(blk_status_t status);
938 blk_status_t errno_to_blk_status(int errno);
939 
940 int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin);
941 
942 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
943 {
944 	return bdev->bd_disk->queue;	/* this is never NULL */
945 }
946 
947 /*
948  * The basic unit of block I/O is a sector. It is used in a number of contexts
949  * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
950  * bytes. Variables of type sector_t represent an offset or size that is a
951  * multiple of 512 bytes. Hence these two constants.
952  */
953 #ifndef SECTOR_SHIFT
954 #define SECTOR_SHIFT 9
955 #endif
956 #ifndef SECTOR_SIZE
957 #define SECTOR_SIZE (1 << SECTOR_SHIFT)
958 #endif
959 
960 /*
961  * blk_rq_pos()			: the current sector
962  * blk_rq_bytes()		: bytes left in the entire request
963  * blk_rq_cur_bytes()		: bytes left in the current segment
964  * blk_rq_err_bytes()		: bytes left till the next error boundary
965  * blk_rq_sectors()		: sectors left in the entire request
966  * blk_rq_cur_sectors()		: sectors left in the current segment
967  * blk_rq_stats_sectors()	: sectors of the entire request used for stats
968  */
969 static inline sector_t blk_rq_pos(const struct request *rq)
970 {
971 	return rq->__sector;
972 }
973 
974 static inline unsigned int blk_rq_bytes(const struct request *rq)
975 {
976 	return rq->__data_len;
977 }
978 
979 static inline int blk_rq_cur_bytes(const struct request *rq)
980 {
981 	return rq->bio ? bio_cur_bytes(rq->bio) : 0;
982 }
983 
984 extern unsigned int blk_rq_err_bytes(const struct request *rq);
985 
986 static inline unsigned int blk_rq_sectors(const struct request *rq)
987 {
988 	return blk_rq_bytes(rq) >> SECTOR_SHIFT;
989 }
990 
991 static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
992 {
993 	return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
994 }
995 
996 static inline unsigned int blk_rq_stats_sectors(const struct request *rq)
997 {
998 	return rq->stats_sectors;
999 }
1000 
1001 #ifdef CONFIG_BLK_DEV_ZONED
1002 
1003 /* Helper to convert BLK_ZONE_ZONE_XXX to its string format XXX */
1004 const char *blk_zone_cond_str(enum blk_zone_cond zone_cond);
1005 
1006 static inline unsigned int blk_rq_zone_no(struct request *rq)
1007 {
1008 	return blk_queue_zone_no(rq->q, blk_rq_pos(rq));
1009 }
1010 
1011 static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
1012 {
1013 	return blk_queue_zone_is_seq(rq->q, blk_rq_pos(rq));
1014 }
1015 #endif /* CONFIG_BLK_DEV_ZONED */
1016 
1017 /*
1018  * Some commands like WRITE SAME have a payload or data transfer size which
1019  * is different from the size of the request.  Any driver that supports such
1020  * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
1021  * calculate the data transfer size.
1022  */
1023 static inline unsigned int blk_rq_payload_bytes(struct request *rq)
1024 {
1025 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1026 		return rq->special_vec.bv_len;
1027 	return blk_rq_bytes(rq);
1028 }
1029 
1030 /*
1031  * Return the first full biovec in the request.  The caller needs to check that
1032  * there are any bvecs before calling this helper.
1033  */
1034 static inline struct bio_vec req_bvec(struct request *rq)
1035 {
1036 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1037 		return rq->special_vec;
1038 	return mp_bvec_iter_bvec(rq->bio->bi_io_vec, rq->bio->bi_iter);
1039 }
1040 
1041 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
1042 						     int op)
1043 {
1044 	if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
1045 		return min(q->limits.max_discard_sectors,
1046 			   UINT_MAX >> SECTOR_SHIFT);
1047 
1048 	if (unlikely(op == REQ_OP_WRITE_SAME))
1049 		return q->limits.max_write_same_sectors;
1050 
1051 	if (unlikely(op == REQ_OP_WRITE_ZEROES))
1052 		return q->limits.max_write_zeroes_sectors;
1053 
1054 	return q->limits.max_sectors;
1055 }
1056 
1057 /*
1058  * Return maximum size of a request at given offset. Only valid for
1059  * file system requests.
1060  */
1061 static inline unsigned int blk_max_size_offset(struct request_queue *q,
1062 					       sector_t offset)
1063 {
1064 	if (!q->limits.chunk_sectors)
1065 		return q->limits.max_sectors;
1066 
1067 	return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
1068 			(offset & (q->limits.chunk_sectors - 1))));
1069 }
1070 
1071 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
1072 						  sector_t offset)
1073 {
1074 	struct request_queue *q = rq->q;
1075 
1076 	if (blk_rq_is_passthrough(rq))
1077 		return q->limits.max_hw_sectors;
1078 
1079 	if (!q->limits.chunk_sectors ||
1080 	    req_op(rq) == REQ_OP_DISCARD ||
1081 	    req_op(rq) == REQ_OP_SECURE_ERASE)
1082 		return blk_queue_get_max_sectors(q, req_op(rq));
1083 
1084 	return min(blk_max_size_offset(q, offset),
1085 			blk_queue_get_max_sectors(q, req_op(rq)));
1086 }
1087 
1088 static inline unsigned int blk_rq_count_bios(struct request *rq)
1089 {
1090 	unsigned int nr_bios = 0;
1091 	struct bio *bio;
1092 
1093 	__rq_for_each_bio(bio, rq)
1094 		nr_bios++;
1095 
1096 	return nr_bios;
1097 }
1098 
1099 void blk_steal_bios(struct bio_list *list, struct request *rq);
1100 
1101 /*
1102  * Request completion related functions.
1103  *
1104  * blk_update_request() completes given number of bytes and updates
1105  * the request without completing it.
1106  */
1107 extern bool blk_update_request(struct request *rq, blk_status_t error,
1108 			       unsigned int nr_bytes);
1109 
1110 extern void blk_abort_request(struct request *);
1111 
1112 /*
1113  * Access functions for manipulating queue properties
1114  */
1115 extern void blk_cleanup_queue(struct request_queue *);
1116 extern void blk_queue_bounce_limit(struct request_queue *, u64);
1117 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1118 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1119 extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1120 extern void blk_queue_max_discard_segments(struct request_queue *,
1121 		unsigned short);
1122 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1123 extern void blk_queue_max_discard_sectors(struct request_queue *q,
1124 		unsigned int max_discard_sectors);
1125 extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1126 		unsigned int max_write_same_sectors);
1127 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
1128 		unsigned int max_write_same_sectors);
1129 extern void blk_queue_logical_block_size(struct request_queue *, unsigned int);
1130 extern void blk_queue_max_zone_append_sectors(struct request_queue *q,
1131 		unsigned int max_zone_append_sectors);
1132 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1133 extern void blk_queue_alignment_offset(struct request_queue *q,
1134 				       unsigned int alignment);
1135 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1136 extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1137 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1138 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1139 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth);
1140 extern void blk_set_default_limits(struct queue_limits *lim);
1141 extern void blk_set_stacking_limits(struct queue_limits *lim);
1142 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1143 			    sector_t offset);
1144 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1145 			      sector_t offset);
1146 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1147 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1148 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1149 extern void blk_queue_dma_alignment(struct request_queue *, int);
1150 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1151 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1152 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1153 extern void blk_queue_required_elevator_features(struct request_queue *q,
1154 						 unsigned int features);
1155 extern bool blk_queue_can_use_dma_map_merging(struct request_queue *q,
1156 					      struct device *dev);
1157 
1158 /*
1159  * Number of physical segments as sent to the device.
1160  *
1161  * Normally this is the number of discontiguous data segments sent by the
1162  * submitter.  But for data-less command like discard we might have no
1163  * actual data segments submitted, but the driver might have to add it's
1164  * own special payload.  In that case we still return 1 here so that this
1165  * special payload will be mapped.
1166  */
1167 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
1168 {
1169 	if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1170 		return 1;
1171 	return rq->nr_phys_segments;
1172 }
1173 
1174 /*
1175  * Number of discard segments (or ranges) the driver needs to fill in.
1176  * Each discard bio merged into a request is counted as one segment.
1177  */
1178 static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
1179 {
1180 	return max_t(unsigned short, rq->nr_phys_segments, 1);
1181 }
1182 
1183 int __blk_rq_map_sg(struct request_queue *q, struct request *rq,
1184 		struct scatterlist *sglist, struct scatterlist **last_sg);
1185 static inline int blk_rq_map_sg(struct request_queue *q, struct request *rq,
1186 		struct scatterlist *sglist)
1187 {
1188 	struct scatterlist *last_sg = NULL;
1189 
1190 	return __blk_rq_map_sg(q, rq, sglist, &last_sg);
1191 }
1192 extern void blk_dump_rq_flags(struct request *, char *);
1193 
1194 bool __must_check blk_get_queue(struct request_queue *);
1195 struct request_queue *blk_alloc_queue(int node_id);
1196 extern void blk_put_queue(struct request_queue *);
1197 extern void blk_set_queue_dying(struct request_queue *);
1198 
1199 #ifdef CONFIG_BLOCK
1200 /*
1201  * blk_plug permits building a queue of related requests by holding the I/O
1202  * fragments for a short period. This allows merging of sequential requests
1203  * into single larger request. As the requests are moved from a per-task list to
1204  * the device's request_queue in a batch, this results in improved scalability
1205  * as the lock contention for request_queue lock is reduced.
1206  *
1207  * It is ok not to disable preemption when adding the request to the plug list
1208  * or when attempting a merge, because blk_schedule_flush_list() will only flush
1209  * the plug list when the task sleeps by itself. For details, please see
1210  * schedule() where blk_schedule_flush_plug() is called.
1211  */
1212 struct blk_plug {
1213 	struct list_head mq_list; /* blk-mq requests */
1214 	struct list_head cb_list; /* md requires an unplug callback */
1215 	unsigned short rq_count;
1216 	bool multiple_queues;
1217 	bool nowait;
1218 };
1219 #define BLK_MAX_REQUEST_COUNT 16
1220 #define BLK_PLUG_FLUSH_SIZE (128 * 1024)
1221 
1222 struct blk_plug_cb;
1223 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1224 struct blk_plug_cb {
1225 	struct list_head list;
1226 	blk_plug_cb_fn callback;
1227 	void *data;
1228 };
1229 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1230 					     void *data, int size);
1231 extern void blk_start_plug(struct blk_plug *);
1232 extern void blk_finish_plug(struct blk_plug *);
1233 extern void blk_flush_plug_list(struct blk_plug *, bool);
1234 
1235 static inline void blk_flush_plug(struct task_struct *tsk)
1236 {
1237 	struct blk_plug *plug = tsk->plug;
1238 
1239 	if (plug)
1240 		blk_flush_plug_list(plug, false);
1241 }
1242 
1243 static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1244 {
1245 	struct blk_plug *plug = tsk->plug;
1246 
1247 	if (plug)
1248 		blk_flush_plug_list(plug, true);
1249 }
1250 
1251 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1252 {
1253 	struct blk_plug *plug = tsk->plug;
1254 
1255 	return plug &&
1256 		 (!list_empty(&plug->mq_list) ||
1257 		 !list_empty(&plug->cb_list));
1258 }
1259 
1260 int blkdev_issue_flush(struct block_device *, gfp_t);
1261 long nr_blockdev_pages(void);
1262 #else /* CONFIG_BLOCK */
1263 struct blk_plug {
1264 };
1265 
1266 static inline void blk_start_plug(struct blk_plug *plug)
1267 {
1268 }
1269 
1270 static inline void blk_finish_plug(struct blk_plug *plug)
1271 {
1272 }
1273 
1274 static inline void blk_flush_plug(struct task_struct *task)
1275 {
1276 }
1277 
1278 static inline void blk_schedule_flush_plug(struct task_struct *task)
1279 {
1280 }
1281 
1282 
1283 static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1284 {
1285 	return false;
1286 }
1287 
1288 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask)
1289 {
1290 	return 0;
1291 }
1292 
1293 static inline long nr_blockdev_pages(void)
1294 {
1295 	return 0;
1296 }
1297 #endif /* CONFIG_BLOCK */
1298 
1299 extern void blk_io_schedule(void);
1300 
1301 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1302 		sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1303 
1304 #define BLKDEV_DISCARD_SECURE	(1 << 0)	/* issue a secure erase */
1305 
1306 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1307 		sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1308 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1309 		sector_t nr_sects, gfp_t gfp_mask, int flags,
1310 		struct bio **biop);
1311 
1312 #define BLKDEV_ZERO_NOUNMAP	(1 << 0)  /* do not free blocks */
1313 #define BLKDEV_ZERO_NOFALLBACK	(1 << 1)  /* don't write explicit zeroes */
1314 
1315 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1316 		sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
1317 		unsigned flags);
1318 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1319 		sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
1320 
1321 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1322 		sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1323 {
1324 	return blkdev_issue_discard(sb->s_bdev,
1325 				    block << (sb->s_blocksize_bits -
1326 					      SECTOR_SHIFT),
1327 				    nr_blocks << (sb->s_blocksize_bits -
1328 						  SECTOR_SHIFT),
1329 				    gfp_mask, flags);
1330 }
1331 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1332 		sector_t nr_blocks, gfp_t gfp_mask)
1333 {
1334 	return blkdev_issue_zeroout(sb->s_bdev,
1335 				    block << (sb->s_blocksize_bits -
1336 					      SECTOR_SHIFT),
1337 				    nr_blocks << (sb->s_blocksize_bits -
1338 						  SECTOR_SHIFT),
1339 				    gfp_mask, 0);
1340 }
1341 
1342 extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
1343 
1344 enum blk_default_limits {
1345 	BLK_MAX_SEGMENTS	= 128,
1346 	BLK_SAFE_MAX_SECTORS	= 255,
1347 	BLK_DEF_MAX_SECTORS	= 2560,
1348 	BLK_MAX_SEGMENT_SIZE	= 65536,
1349 	BLK_SEG_BOUNDARY_MASK	= 0xFFFFFFFFUL,
1350 };
1351 
1352 static inline unsigned long queue_segment_boundary(const struct request_queue *q)
1353 {
1354 	return q->limits.seg_boundary_mask;
1355 }
1356 
1357 static inline unsigned long queue_virt_boundary(const struct request_queue *q)
1358 {
1359 	return q->limits.virt_boundary_mask;
1360 }
1361 
1362 static inline unsigned int queue_max_sectors(const struct request_queue *q)
1363 {
1364 	return q->limits.max_sectors;
1365 }
1366 
1367 static inline unsigned int queue_max_hw_sectors(const struct request_queue *q)
1368 {
1369 	return q->limits.max_hw_sectors;
1370 }
1371 
1372 static inline unsigned short queue_max_segments(const struct request_queue *q)
1373 {
1374 	return q->limits.max_segments;
1375 }
1376 
1377 static inline unsigned short queue_max_discard_segments(const struct request_queue *q)
1378 {
1379 	return q->limits.max_discard_segments;
1380 }
1381 
1382 static inline unsigned int queue_max_segment_size(const struct request_queue *q)
1383 {
1384 	return q->limits.max_segment_size;
1385 }
1386 
1387 static inline unsigned int queue_max_zone_append_sectors(const struct request_queue *q)
1388 {
1389 	return q->limits.max_zone_append_sectors;
1390 }
1391 
1392 static inline unsigned queue_logical_block_size(const struct request_queue *q)
1393 {
1394 	int retval = 512;
1395 
1396 	if (q && q->limits.logical_block_size)
1397 		retval = q->limits.logical_block_size;
1398 
1399 	return retval;
1400 }
1401 
1402 static inline unsigned int bdev_logical_block_size(struct block_device *bdev)
1403 {
1404 	return queue_logical_block_size(bdev_get_queue(bdev));
1405 }
1406 
1407 static inline unsigned int queue_physical_block_size(const struct request_queue *q)
1408 {
1409 	return q->limits.physical_block_size;
1410 }
1411 
1412 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1413 {
1414 	return queue_physical_block_size(bdev_get_queue(bdev));
1415 }
1416 
1417 static inline unsigned int queue_io_min(const struct request_queue *q)
1418 {
1419 	return q->limits.io_min;
1420 }
1421 
1422 static inline int bdev_io_min(struct block_device *bdev)
1423 {
1424 	return queue_io_min(bdev_get_queue(bdev));
1425 }
1426 
1427 static inline unsigned int queue_io_opt(const struct request_queue *q)
1428 {
1429 	return q->limits.io_opt;
1430 }
1431 
1432 static inline int bdev_io_opt(struct block_device *bdev)
1433 {
1434 	return queue_io_opt(bdev_get_queue(bdev));
1435 }
1436 
1437 static inline int queue_alignment_offset(const struct request_queue *q)
1438 {
1439 	if (q->limits.misaligned)
1440 		return -1;
1441 
1442 	return q->limits.alignment_offset;
1443 }
1444 
1445 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1446 {
1447 	unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1448 	unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1449 		<< SECTOR_SHIFT;
1450 
1451 	return (granularity + lim->alignment_offset - alignment) % granularity;
1452 }
1453 
1454 static inline int bdev_alignment_offset(struct block_device *bdev)
1455 {
1456 	struct request_queue *q = bdev_get_queue(bdev);
1457 
1458 	if (q->limits.misaligned)
1459 		return -1;
1460 
1461 	if (bdev != bdev->bd_contains)
1462 		return bdev->bd_part->alignment_offset;
1463 
1464 	return q->limits.alignment_offset;
1465 }
1466 
1467 static inline int queue_discard_alignment(const struct request_queue *q)
1468 {
1469 	if (q->limits.discard_misaligned)
1470 		return -1;
1471 
1472 	return q->limits.discard_alignment;
1473 }
1474 
1475 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1476 {
1477 	unsigned int alignment, granularity, offset;
1478 
1479 	if (!lim->max_discard_sectors)
1480 		return 0;
1481 
1482 	/* Why are these in bytes, not sectors? */
1483 	alignment = lim->discard_alignment >> SECTOR_SHIFT;
1484 	granularity = lim->discard_granularity >> SECTOR_SHIFT;
1485 	if (!granularity)
1486 		return 0;
1487 
1488 	/* Offset of the partition start in 'granularity' sectors */
1489 	offset = sector_div(sector, granularity);
1490 
1491 	/* And why do we do this modulus *again* in blkdev_issue_discard()? */
1492 	offset = (granularity + alignment - offset) % granularity;
1493 
1494 	/* Turn it back into bytes, gaah */
1495 	return offset << SECTOR_SHIFT;
1496 }
1497 
1498 static inline int bdev_discard_alignment(struct block_device *bdev)
1499 {
1500 	struct request_queue *q = bdev_get_queue(bdev);
1501 
1502 	if (bdev != bdev->bd_contains)
1503 		return bdev->bd_part->discard_alignment;
1504 
1505 	return q->limits.discard_alignment;
1506 }
1507 
1508 static inline unsigned int bdev_write_same(struct block_device *bdev)
1509 {
1510 	struct request_queue *q = bdev_get_queue(bdev);
1511 
1512 	if (q)
1513 		return q->limits.max_write_same_sectors;
1514 
1515 	return 0;
1516 }
1517 
1518 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
1519 {
1520 	struct request_queue *q = bdev_get_queue(bdev);
1521 
1522 	if (q)
1523 		return q->limits.max_write_zeroes_sectors;
1524 
1525 	return 0;
1526 }
1527 
1528 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
1529 {
1530 	struct request_queue *q = bdev_get_queue(bdev);
1531 
1532 	if (q)
1533 		return blk_queue_zoned_model(q);
1534 
1535 	return BLK_ZONED_NONE;
1536 }
1537 
1538 static inline bool bdev_is_zoned(struct block_device *bdev)
1539 {
1540 	struct request_queue *q = bdev_get_queue(bdev);
1541 
1542 	if (q)
1543 		return blk_queue_is_zoned(q);
1544 
1545 	return false;
1546 }
1547 
1548 static inline sector_t bdev_zone_sectors(struct block_device *bdev)
1549 {
1550 	struct request_queue *q = bdev_get_queue(bdev);
1551 
1552 	if (q)
1553 		return blk_queue_zone_sectors(q);
1554 	return 0;
1555 }
1556 
1557 static inline unsigned int bdev_max_open_zones(struct block_device *bdev)
1558 {
1559 	struct request_queue *q = bdev_get_queue(bdev);
1560 
1561 	if (q)
1562 		return queue_max_open_zones(q);
1563 	return 0;
1564 }
1565 
1566 static inline unsigned int bdev_max_active_zones(struct block_device *bdev)
1567 {
1568 	struct request_queue *q = bdev_get_queue(bdev);
1569 
1570 	if (q)
1571 		return queue_max_active_zones(q);
1572 	return 0;
1573 }
1574 
1575 static inline int queue_dma_alignment(const struct request_queue *q)
1576 {
1577 	return q ? q->dma_alignment : 511;
1578 }
1579 
1580 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1581 				 unsigned int len)
1582 {
1583 	unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1584 	return !(addr & alignment) && !(len & alignment);
1585 }
1586 
1587 /* assumes size > 256 */
1588 static inline unsigned int blksize_bits(unsigned int size)
1589 {
1590 	unsigned int bits = 8;
1591 	do {
1592 		bits++;
1593 		size >>= 1;
1594 	} while (size > 256);
1595 	return bits;
1596 }
1597 
1598 static inline unsigned int block_size(struct block_device *bdev)
1599 {
1600 	return 1 << bdev->bd_inode->i_blkbits;
1601 }
1602 
1603 int kblockd_schedule_work(struct work_struct *work);
1604 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1605 
1606 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1607 	MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1608 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1609 	MODULE_ALIAS("block-major-" __stringify(major) "-*")
1610 
1611 #if defined(CONFIG_BLK_DEV_INTEGRITY)
1612 
1613 enum blk_integrity_flags {
1614 	BLK_INTEGRITY_VERIFY		= 1 << 0,
1615 	BLK_INTEGRITY_GENERATE		= 1 << 1,
1616 	BLK_INTEGRITY_DEVICE_CAPABLE	= 1 << 2,
1617 	BLK_INTEGRITY_IP_CHECKSUM	= 1 << 3,
1618 };
1619 
1620 struct blk_integrity_iter {
1621 	void			*prot_buf;
1622 	void			*data_buf;
1623 	sector_t		seed;
1624 	unsigned int		data_size;
1625 	unsigned short		interval;
1626 	const char		*disk_name;
1627 };
1628 
1629 typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
1630 typedef void (integrity_prepare_fn) (struct request *);
1631 typedef void (integrity_complete_fn) (struct request *, unsigned int);
1632 
1633 struct blk_integrity_profile {
1634 	integrity_processing_fn		*generate_fn;
1635 	integrity_processing_fn		*verify_fn;
1636 	integrity_prepare_fn		*prepare_fn;
1637 	integrity_complete_fn		*complete_fn;
1638 	const char			*name;
1639 };
1640 
1641 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1642 extern void blk_integrity_unregister(struct gendisk *);
1643 extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1644 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1645 				   struct scatterlist *);
1646 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1647 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1648 				   struct request *);
1649 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1650 				    struct bio *);
1651 
1652 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1653 {
1654 	struct blk_integrity *bi = &disk->queue->integrity;
1655 
1656 	if (!bi->profile)
1657 		return NULL;
1658 
1659 	return bi;
1660 }
1661 
1662 static inline
1663 struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1664 {
1665 	return blk_get_integrity(bdev->bd_disk);
1666 }
1667 
1668 static inline bool
1669 blk_integrity_queue_supports_integrity(struct request_queue *q)
1670 {
1671 	return q->integrity.profile;
1672 }
1673 
1674 static inline bool blk_integrity_rq(struct request *rq)
1675 {
1676 	return rq->cmd_flags & REQ_INTEGRITY;
1677 }
1678 
1679 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1680 						    unsigned int segs)
1681 {
1682 	q->limits.max_integrity_segments = segs;
1683 }
1684 
1685 static inline unsigned short
1686 queue_max_integrity_segments(const struct request_queue *q)
1687 {
1688 	return q->limits.max_integrity_segments;
1689 }
1690 
1691 /**
1692  * bio_integrity_intervals - Return number of integrity intervals for a bio
1693  * @bi:		blk_integrity profile for device
1694  * @sectors:	Size of the bio in 512-byte sectors
1695  *
1696  * Description: The block layer calculates everything in 512 byte
1697  * sectors but integrity metadata is done in terms of the data integrity
1698  * interval size of the storage device.  Convert the block layer sectors
1699  * to the appropriate number of integrity intervals.
1700  */
1701 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1702 						   unsigned int sectors)
1703 {
1704 	return sectors >> (bi->interval_exp - 9);
1705 }
1706 
1707 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1708 					       unsigned int sectors)
1709 {
1710 	return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
1711 }
1712 
1713 /*
1714  * Return the first bvec that contains integrity data.  Only drivers that are
1715  * limited to a single integrity segment should use this helper.
1716  */
1717 static inline struct bio_vec *rq_integrity_vec(struct request *rq)
1718 {
1719 	if (WARN_ON_ONCE(queue_max_integrity_segments(rq->q) > 1))
1720 		return NULL;
1721 	return rq->bio->bi_integrity->bip_vec;
1722 }
1723 
1724 #else /* CONFIG_BLK_DEV_INTEGRITY */
1725 
1726 struct bio;
1727 struct block_device;
1728 struct gendisk;
1729 struct blk_integrity;
1730 
1731 static inline int blk_integrity_rq(struct request *rq)
1732 {
1733 	return 0;
1734 }
1735 static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1736 					    struct bio *b)
1737 {
1738 	return 0;
1739 }
1740 static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1741 					  struct bio *b,
1742 					  struct scatterlist *s)
1743 {
1744 	return 0;
1745 }
1746 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1747 {
1748 	return NULL;
1749 }
1750 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1751 {
1752 	return NULL;
1753 }
1754 static inline bool
1755 blk_integrity_queue_supports_integrity(struct request_queue *q)
1756 {
1757 	return false;
1758 }
1759 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1760 {
1761 	return 0;
1762 }
1763 static inline void blk_integrity_register(struct gendisk *d,
1764 					 struct blk_integrity *b)
1765 {
1766 }
1767 static inline void blk_integrity_unregister(struct gendisk *d)
1768 {
1769 }
1770 static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1771 						    unsigned int segs)
1772 {
1773 }
1774 static inline unsigned short queue_max_integrity_segments(const struct request_queue *q)
1775 {
1776 	return 0;
1777 }
1778 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1779 					  struct request *r1,
1780 					  struct request *r2)
1781 {
1782 	return true;
1783 }
1784 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1785 					   struct request *r,
1786 					   struct bio *b)
1787 {
1788 	return true;
1789 }
1790 
1791 static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1792 						   unsigned int sectors)
1793 {
1794 	return 0;
1795 }
1796 
1797 static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1798 					       unsigned int sectors)
1799 {
1800 	return 0;
1801 }
1802 
1803 static inline struct bio_vec *rq_integrity_vec(struct request *rq)
1804 {
1805 	return NULL;
1806 }
1807 
1808 #endif /* CONFIG_BLK_DEV_INTEGRITY */
1809 
1810 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
1811 
1812 bool blk_ksm_register(struct blk_keyslot_manager *ksm, struct request_queue *q);
1813 
1814 void blk_ksm_unregister(struct request_queue *q);
1815 
1816 #else /* CONFIG_BLK_INLINE_ENCRYPTION */
1817 
1818 static inline bool blk_ksm_register(struct blk_keyslot_manager *ksm,
1819 				    struct request_queue *q)
1820 {
1821 	return true;
1822 }
1823 
1824 static inline void blk_ksm_unregister(struct request_queue *q) { }
1825 
1826 #endif /* CONFIG_BLK_INLINE_ENCRYPTION */
1827 
1828 
1829 struct block_device_operations {
1830 	blk_qc_t (*submit_bio) (struct bio *bio);
1831 	int (*open) (struct block_device *, fmode_t);
1832 	void (*release) (struct gendisk *, fmode_t);
1833 	int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
1834 	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1835 	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1836 	unsigned int (*check_events) (struct gendisk *disk,
1837 				      unsigned int clearing);
1838 	void (*unlock_native_capacity) (struct gendisk *);
1839 	int (*revalidate_disk) (struct gendisk *);
1840 	int (*getgeo)(struct block_device *, struct hd_geometry *);
1841 	/* this callback is with swap_lock and sometimes page table lock held */
1842 	void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1843 	int (*report_zones)(struct gendisk *, sector_t sector,
1844 			unsigned int nr_zones, report_zones_cb cb, void *data);
1845 	char *(*devnode)(struct gendisk *disk, umode_t *mode);
1846 	struct module *owner;
1847 	const struct pr_ops *pr_ops;
1848 };
1849 
1850 #ifdef CONFIG_COMPAT
1851 extern int blkdev_compat_ptr_ioctl(struct block_device *, fmode_t,
1852 				      unsigned int, unsigned long);
1853 #else
1854 #define blkdev_compat_ptr_ioctl NULL
1855 #endif
1856 
1857 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1858 				 unsigned long);
1859 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1860 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1861 						struct writeback_control *);
1862 
1863 #ifdef CONFIG_BLK_DEV_ZONED
1864 bool blk_req_needs_zone_write_lock(struct request *rq);
1865 bool blk_req_zone_write_trylock(struct request *rq);
1866 void __blk_req_zone_write_lock(struct request *rq);
1867 void __blk_req_zone_write_unlock(struct request *rq);
1868 
1869 static inline void blk_req_zone_write_lock(struct request *rq)
1870 {
1871 	if (blk_req_needs_zone_write_lock(rq))
1872 		__blk_req_zone_write_lock(rq);
1873 }
1874 
1875 static inline void blk_req_zone_write_unlock(struct request *rq)
1876 {
1877 	if (rq->rq_flags & RQF_ZONE_WRITE_LOCKED)
1878 		__blk_req_zone_write_unlock(rq);
1879 }
1880 
1881 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1882 {
1883 	return rq->q->seq_zones_wlock &&
1884 		test_bit(blk_rq_zone_no(rq), rq->q->seq_zones_wlock);
1885 }
1886 
1887 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1888 {
1889 	if (!blk_req_needs_zone_write_lock(rq))
1890 		return true;
1891 	return !blk_req_zone_is_write_locked(rq);
1892 }
1893 #else
1894 static inline bool blk_req_needs_zone_write_lock(struct request *rq)
1895 {
1896 	return false;
1897 }
1898 
1899 static inline void blk_req_zone_write_lock(struct request *rq)
1900 {
1901 }
1902 
1903 static inline void blk_req_zone_write_unlock(struct request *rq)
1904 {
1905 }
1906 static inline bool blk_req_zone_is_write_locked(struct request *rq)
1907 {
1908 	return false;
1909 }
1910 
1911 static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
1912 {
1913 	return true;
1914 }
1915 #endif /* CONFIG_BLK_DEV_ZONED */
1916 
1917 static inline void blk_wake_io_task(struct task_struct *waiter)
1918 {
1919 	/*
1920 	 * If we're polling, the task itself is doing the completions. For
1921 	 * that case, we don't need to signal a wakeup, it's enough to just
1922 	 * mark us as RUNNING.
1923 	 */
1924 	if (waiter == current)
1925 		__set_current_state(TASK_RUNNING);
1926 	else
1927 		wake_up_process(waiter);
1928 }
1929 
1930 unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,
1931 		unsigned int op);
1932 void disk_end_io_acct(struct gendisk *disk, unsigned int op,
1933 		unsigned long start_time);
1934 
1935 /**
1936  * bio_start_io_acct - start I/O accounting for bio based drivers
1937  * @bio:	bio to start account for
1938  *
1939  * Returns the start time that should be passed back to bio_end_io_acct().
1940  */
1941 static inline unsigned long bio_start_io_acct(struct bio *bio)
1942 {
1943 	return disk_start_io_acct(bio->bi_disk, bio_sectors(bio), bio_op(bio));
1944 }
1945 
1946 /**
1947  * bio_end_io_acct - end I/O accounting for bio based drivers
1948  * @bio:	bio to end account for
1949  * @start:	start time returned by bio_start_io_acct()
1950  */
1951 static inline void bio_end_io_acct(struct bio *bio, unsigned long start_time)
1952 {
1953 	return disk_end_io_acct(bio->bi_disk, bio_op(bio), start_time);
1954 }
1955 
1956 int bdev_read_only(struct block_device *bdev);
1957 int set_blocksize(struct block_device *bdev, int size);
1958 
1959 const char *bdevname(struct block_device *bdev, char *buffer);
1960 struct block_device *lookup_bdev(const char *);
1961 
1962 void blkdev_show(struct seq_file *seqf, off_t offset);
1963 
1964 #define BDEVNAME_SIZE	32	/* Largest string for a blockdev identifier */
1965 #define BDEVT_SIZE	10	/* Largest string for MAJ:MIN for blkdev */
1966 #ifdef CONFIG_BLOCK
1967 #define BLKDEV_MAJOR_MAX	512
1968 #else
1969 #define BLKDEV_MAJOR_MAX	0
1970 #endif
1971 
1972 int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder);
1973 struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
1974 		void *holder);
1975 struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, void *holder);
1976 int bd_prepare_to_claim(struct block_device *bdev, struct block_device *whole,
1977 		void *holder);
1978 void bd_abort_claiming(struct block_device *bdev, struct block_device *whole,
1979 		void *holder);
1980 void blkdev_put(struct block_device *bdev, fmode_t mode);
1981 
1982 struct block_device *I_BDEV(struct inode *inode);
1983 struct block_device *bdget(dev_t);
1984 struct block_device *bdgrab(struct block_device *bdev);
1985 void bdput(struct block_device *);
1986 
1987 #ifdef CONFIG_BLOCK
1988 void invalidate_bdev(struct block_device *bdev);
1989 int sync_blockdev(struct block_device *bdev);
1990 #else
1991 static inline void invalidate_bdev(struct block_device *bdev)
1992 {
1993 }
1994 static inline int sync_blockdev(struct block_device *bdev)
1995 {
1996 	return 0;
1997 }
1998 #endif
1999 int fsync_bdev(struct block_device *bdev);
2000 
2001 struct super_block *freeze_bdev(struct block_device *bdev);
2002 int thaw_bdev(struct block_device *bdev, struct super_block *sb);
2003 
2004 #endif /* _LINUX_BLKDEV_H */
2005