xref: /linux-6.15/include/linux/blkdev.h (revision 5e40f445)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Portions Copyright (C) 1992 Drew Eckhardt
4  */
5 #ifndef _LINUX_BLKDEV_H
6 #define _LINUX_BLKDEV_H
7 
8 #include <linux/types.h>
9 #include <linux/blk_types.h>
10 #include <linux/device.h>
11 #include <linux/list.h>
12 #include <linux/llist.h>
13 #include <linux/minmax.h>
14 #include <linux/timer.h>
15 #include <linux/workqueue.h>
16 #include <linux/wait.h>
17 #include <linux/bio.h>
18 #include <linux/gfp.h>
19 #include <linux/kdev_t.h>
20 #include <linux/rcupdate.h>
21 #include <linux/percpu-refcount.h>
22 #include <linux/blkzoned.h>
23 #include <linux/sched.h>
24 #include <linux/sbitmap.h>
25 #include <linux/uuid.h>
26 #include <linux/xarray.h>
27 #include <linux/file.h>
28 #include <linux/lockdep.h>
29 
30 struct module;
31 struct request_queue;
32 struct elevator_queue;
33 struct blk_trace;
34 struct request;
35 struct sg_io_hdr;
36 struct blkcg_gq;
37 struct blk_flush_queue;
38 struct kiocb;
39 struct pr_ops;
40 struct rq_qos;
41 struct blk_queue_stats;
42 struct blk_stat_callback;
43 struct blk_crypto_profile;
44 
45 extern const struct device_type disk_type;
46 extern const struct device_type part_type;
47 extern const struct class block_class;
48 
49 /*
50  * Maximum number of blkcg policies allowed to be registered concurrently.
51  * Defined here to simplify include dependency.
52  */
53 #define BLKCG_MAX_POLS		6
54 
55 #define DISK_MAX_PARTS			256
56 #define DISK_NAME_LEN			32
57 
58 #define PARTITION_META_INFO_VOLNAMELTH	64
59 /*
60  * Enough for the string representation of any kind of UUID plus NULL.
61  * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
62  */
63 #define PARTITION_META_INFO_UUIDLTH	(UUID_STRING_LEN + 1)
64 
65 struct partition_meta_info {
66 	char uuid[PARTITION_META_INFO_UUIDLTH];
67 	u8 volname[PARTITION_META_INFO_VOLNAMELTH];
68 };
69 
70 /**
71  * DOC: genhd capability flags
72  *
73  * ``GENHD_FL_REMOVABLE``: indicates that the block device gives access to
74  * removable media.  When set, the device remains present even when media is not
75  * inserted.  Shall not be set for devices which are removed entirely when the
76  * media is removed.
77  *
78  * ``GENHD_FL_HIDDEN``: the block device is hidden; it doesn't produce events,
79  * doesn't appear in sysfs, and can't be opened from userspace or using
80  * blkdev_get*. Used for the underlying components of multipath devices.
81  *
82  * ``GENHD_FL_NO_PART``: partition support is disabled.  The kernel will not
83  * scan for partitions from add_disk, and users can't add partitions manually.
84  *
85  */
86 enum {
87 	GENHD_FL_REMOVABLE			= 1 << 0,
88 	GENHD_FL_HIDDEN				= 1 << 1,
89 	GENHD_FL_NO_PART			= 1 << 2,
90 };
91 
92 enum {
93 	DISK_EVENT_MEDIA_CHANGE			= 1 << 0, /* media changed */
94 	DISK_EVENT_EJECT_REQUEST		= 1 << 1, /* eject requested */
95 };
96 
97 enum {
98 	/* Poll even if events_poll_msecs is unset */
99 	DISK_EVENT_FLAG_POLL			= 1 << 0,
100 	/* Forward events to udev */
101 	DISK_EVENT_FLAG_UEVENT			= 1 << 1,
102 	/* Block event polling when open for exclusive write */
103 	DISK_EVENT_FLAG_BLOCK_ON_EXCL_WRITE	= 1 << 2,
104 };
105 
106 struct disk_events;
107 struct badblocks;
108 
109 enum blk_integrity_checksum {
110 	BLK_INTEGRITY_CSUM_NONE		= 0,
111 	BLK_INTEGRITY_CSUM_IP		= 1,
112 	BLK_INTEGRITY_CSUM_CRC		= 2,
113 	BLK_INTEGRITY_CSUM_CRC64	= 3,
114 } __packed ;
115 
116 struct blk_integrity {
117 	unsigned char				flags;
118 	enum blk_integrity_checksum		csum_type;
119 	unsigned char				tuple_size;
120 	unsigned char				pi_offset;
121 	unsigned char				interval_exp;
122 	unsigned char				tag_size;
123 };
124 
125 typedef unsigned int __bitwise blk_mode_t;
126 
127 /* open for reading */
128 #define BLK_OPEN_READ		((__force blk_mode_t)(1 << 0))
129 /* open for writing */
130 #define BLK_OPEN_WRITE		((__force blk_mode_t)(1 << 1))
131 /* open exclusively (vs other exclusive openers */
132 #define BLK_OPEN_EXCL		((__force blk_mode_t)(1 << 2))
133 /* opened with O_NDELAY */
134 #define BLK_OPEN_NDELAY		((__force blk_mode_t)(1 << 3))
135 /* open for "writes" only for ioctls (specialy hack for floppy.c) */
136 #define BLK_OPEN_WRITE_IOCTL	((__force blk_mode_t)(1 << 4))
137 /* open is exclusive wrt all other BLK_OPEN_WRITE opens to the device */
138 #define BLK_OPEN_RESTRICT_WRITES	((__force blk_mode_t)(1 << 5))
139 /* return partition scanning errors */
140 #define BLK_OPEN_STRICT_SCAN	((__force blk_mode_t)(1 << 6))
141 
142 struct gendisk {
143 	/*
144 	 * major/first_minor/minors should not be set by any new driver, the
145 	 * block core will take care of allocating them automatically.
146 	 */
147 	int major;
148 	int first_minor;
149 	int minors;
150 
151 	char disk_name[DISK_NAME_LEN];	/* name of major driver */
152 
153 	unsigned short events;		/* supported events */
154 	unsigned short event_flags;	/* flags related to event processing */
155 
156 	struct xarray part_tbl;
157 	struct block_device *part0;
158 
159 	const struct block_device_operations *fops;
160 	struct request_queue *queue;
161 	void *private_data;
162 
163 	struct bio_set bio_split;
164 
165 	int flags;
166 	unsigned long state;
167 #define GD_NEED_PART_SCAN		0
168 #define GD_READ_ONLY			1
169 #define GD_DEAD				2
170 #define GD_NATIVE_CAPACITY		3
171 #define GD_ADDED			4
172 #define GD_SUPPRESS_PART_SCAN		5
173 #define GD_OWNS_QUEUE			6
174 
175 	struct mutex open_mutex;	/* open/close mutex */
176 	unsigned open_partitions;	/* number of open partitions */
177 
178 	struct backing_dev_info	*bdi;
179 	struct kobject queue_kobj;	/* the queue/ directory */
180 	struct kobject *slave_dir;
181 #ifdef CONFIG_BLOCK_HOLDER_DEPRECATED
182 	struct list_head slave_bdevs;
183 #endif
184 	struct timer_rand_state *random;
185 	atomic_t sync_io;		/* RAID */
186 	struct disk_events *ev;
187 
188 #ifdef CONFIG_BLK_DEV_ZONED
189 	/*
190 	 * Zoned block device information. Reads of this information must be
191 	 * protected with blk_queue_enter() / blk_queue_exit(). Modifying this
192 	 * information is only allowed while no requests are being processed.
193 	 * See also blk_mq_freeze_queue() and blk_mq_unfreeze_queue().
194 	 */
195 	unsigned int		nr_zones;
196 	unsigned int		zone_capacity;
197 	unsigned int		last_zone_capacity;
198 	unsigned long __rcu	*conv_zones_bitmap;
199 	unsigned int            zone_wplugs_hash_bits;
200 	spinlock_t              zone_wplugs_lock;
201 	struct mempool_s	*zone_wplugs_pool;
202 	struct hlist_head       *zone_wplugs_hash;
203 	struct workqueue_struct *zone_wplugs_wq;
204 #endif /* CONFIG_BLK_DEV_ZONED */
205 
206 #if IS_ENABLED(CONFIG_CDROM)
207 	struct cdrom_device_info *cdi;
208 #endif
209 	int node_id;
210 	struct badblocks *bb;
211 	struct lockdep_map lockdep_map;
212 	u64 diskseq;
213 	blk_mode_t open_mode;
214 
215 	/*
216 	 * Independent sector access ranges. This is always NULL for
217 	 * devices that do not have multiple independent access ranges.
218 	 */
219 	struct blk_independent_access_ranges *ia_ranges;
220 };
221 
222 /**
223  * disk_openers - returns how many openers are there for a disk
224  * @disk: disk to check
225  *
226  * This returns the number of openers for a disk.  Note that this value is only
227  * stable if disk->open_mutex is held.
228  *
229  * Note: Due to a quirk in the block layer open code, each open partition is
230  * only counted once even if there are multiple openers.
231  */
232 static inline unsigned int disk_openers(struct gendisk *disk)
233 {
234 	return atomic_read(&disk->part0->bd_openers);
235 }
236 
237 /**
238  * disk_has_partscan - return %true if partition scanning is enabled on a disk
239  * @disk: disk to check
240  *
241  * Returns %true if partitions scanning is enabled for @disk, or %false if
242  * partition scanning is disabled either permanently or temporarily.
243  */
244 static inline bool disk_has_partscan(struct gendisk *disk)
245 {
246 	return !(disk->flags & (GENHD_FL_NO_PART | GENHD_FL_HIDDEN)) &&
247 		!test_bit(GD_SUPPRESS_PART_SCAN, &disk->state);
248 }
249 
250 /*
251  * The gendisk is refcounted by the part0 block_device, and the bd_device
252  * therein is also used for device model presentation in sysfs.
253  */
254 #define dev_to_disk(device) \
255 	(dev_to_bdev(device)->bd_disk)
256 #define disk_to_dev(disk) \
257 	(&((disk)->part0->bd_device))
258 
259 #if IS_REACHABLE(CONFIG_CDROM)
260 #define disk_to_cdi(disk)	((disk)->cdi)
261 #else
262 #define disk_to_cdi(disk)	NULL
263 #endif
264 
265 static inline dev_t disk_devt(struct gendisk *disk)
266 {
267 	return MKDEV(disk->major, disk->first_minor);
268 }
269 
270 /* blk_validate_limits() validates bsize, so drivers don't usually need to */
271 static inline int blk_validate_block_size(unsigned long bsize)
272 {
273 	if (bsize < 512 || bsize > PAGE_SIZE || !is_power_of_2(bsize))
274 		return -EINVAL;
275 
276 	return 0;
277 }
278 
279 static inline bool blk_op_is_passthrough(blk_opf_t op)
280 {
281 	op &= REQ_OP_MASK;
282 	return op == REQ_OP_DRV_IN || op == REQ_OP_DRV_OUT;
283 }
284 
285 /* flags set by the driver in queue_limits.features */
286 typedef unsigned int __bitwise blk_features_t;
287 
288 /* supports a volatile write cache */
289 #define BLK_FEAT_WRITE_CACHE		((__force blk_features_t)(1u << 0))
290 
291 /* supports passing on the FUA bit */
292 #define BLK_FEAT_FUA			((__force blk_features_t)(1u << 1))
293 
294 /* rotational device (hard drive or floppy) */
295 #define BLK_FEAT_ROTATIONAL		((__force blk_features_t)(1u << 2))
296 
297 /* contributes to the random number pool */
298 #define BLK_FEAT_ADD_RANDOM		((__force blk_features_t)(1u << 3))
299 
300 /* do disk/partitions IO accounting */
301 #define BLK_FEAT_IO_STAT		((__force blk_features_t)(1u << 4))
302 
303 /* don't modify data until writeback is done */
304 #define BLK_FEAT_STABLE_WRITES		((__force blk_features_t)(1u << 5))
305 
306 /* always completes in submit context */
307 #define BLK_FEAT_SYNCHRONOUS		((__force blk_features_t)(1u << 6))
308 
309 /* supports REQ_NOWAIT */
310 #define BLK_FEAT_NOWAIT			((__force blk_features_t)(1u << 7))
311 
312 /* supports DAX */
313 #define BLK_FEAT_DAX			((__force blk_features_t)(1u << 8))
314 
315 /* supports I/O polling */
316 #define BLK_FEAT_POLL			((__force blk_features_t)(1u << 9))
317 
318 /* is a zoned device */
319 #define BLK_FEAT_ZONED			((__force blk_features_t)(1u << 10))
320 
321 /* supports PCI(e) p2p requests */
322 #define BLK_FEAT_PCI_P2PDMA		((__force blk_features_t)(1u << 12))
323 
324 /* skip this queue in blk_mq_(un)quiesce_tagset */
325 #define BLK_FEAT_SKIP_TAGSET_QUIESCE	((__force blk_features_t)(1u << 13))
326 
327 /* bounce all highmem pages */
328 #define BLK_FEAT_BOUNCE_HIGH		((__force blk_features_t)(1u << 14))
329 
330 /* undocumented magic for bcache */
331 #define BLK_FEAT_RAID_PARTIAL_STRIPES_EXPENSIVE \
332 	((__force blk_features_t)(1u << 15))
333 
334 /* atomic writes enabled */
335 #define BLK_FEAT_ATOMIC_WRITES \
336 	((__force blk_features_t)(1u << 16))
337 
338 /*
339  * Flags automatically inherited when stacking limits.
340  */
341 #define BLK_FEAT_INHERIT_MASK \
342 	(BLK_FEAT_WRITE_CACHE | BLK_FEAT_FUA | BLK_FEAT_ROTATIONAL | \
343 	 BLK_FEAT_STABLE_WRITES | BLK_FEAT_ZONED | BLK_FEAT_BOUNCE_HIGH | \
344 	 BLK_FEAT_RAID_PARTIAL_STRIPES_EXPENSIVE)
345 
346 /* internal flags in queue_limits.flags */
347 typedef unsigned int __bitwise blk_flags_t;
348 
349 /* do not send FLUSH/FUA commands despite advertising a write cache */
350 #define BLK_FLAG_WRITE_CACHE_DISABLED	((__force blk_flags_t)(1u << 0))
351 
352 /* I/O topology is misaligned */
353 #define BLK_FLAG_MISALIGNED		((__force blk_flags_t)(1u << 1))
354 
355 /* passthrough command IO accounting */
356 #define BLK_FLAG_IOSTATS_PASSTHROUGH	((__force blk_flags_t)(1u << 2))
357 
358 struct queue_limits {
359 	blk_features_t		features;
360 	blk_flags_t		flags;
361 	unsigned long		seg_boundary_mask;
362 	unsigned long		virt_boundary_mask;
363 
364 	unsigned int		max_hw_sectors;
365 	unsigned int		max_dev_sectors;
366 	unsigned int		chunk_sectors;
367 	unsigned int		max_sectors;
368 	unsigned int		max_user_sectors;
369 	unsigned int		max_segment_size;
370 	unsigned int		physical_block_size;
371 	unsigned int		logical_block_size;
372 	unsigned int		alignment_offset;
373 	unsigned int		io_min;
374 	unsigned int		io_opt;
375 	unsigned int		max_discard_sectors;
376 	unsigned int		max_hw_discard_sectors;
377 	unsigned int		max_user_discard_sectors;
378 	unsigned int		max_secure_erase_sectors;
379 	unsigned int		max_write_zeroes_sectors;
380 	unsigned int		max_hw_zone_append_sectors;
381 	unsigned int		max_zone_append_sectors;
382 	unsigned int		discard_granularity;
383 	unsigned int		discard_alignment;
384 	unsigned int		zone_write_granularity;
385 
386 	/* atomic write limits */
387 	unsigned int		atomic_write_hw_max;
388 	unsigned int		atomic_write_max_sectors;
389 	unsigned int		atomic_write_hw_boundary;
390 	unsigned int		atomic_write_boundary_sectors;
391 	unsigned int		atomic_write_hw_unit_min;
392 	unsigned int		atomic_write_unit_min;
393 	unsigned int		atomic_write_hw_unit_max;
394 	unsigned int		atomic_write_unit_max;
395 
396 	unsigned short		max_segments;
397 	unsigned short		max_integrity_segments;
398 	unsigned short		max_discard_segments;
399 
400 	unsigned int		max_open_zones;
401 	unsigned int		max_active_zones;
402 
403 	/*
404 	 * Drivers that set dma_alignment to less than 511 must be prepared to
405 	 * handle individual bvec's that are not a multiple of a SECTOR_SIZE
406 	 * due to possible offsets.
407 	 */
408 	unsigned int		dma_alignment;
409 	unsigned int		dma_pad_mask;
410 
411 	struct blk_integrity	integrity;
412 };
413 
414 typedef int (*report_zones_cb)(struct blk_zone *zone, unsigned int idx,
415 			       void *data);
416 
417 #define BLK_ALL_ZONES  ((unsigned int)-1)
418 int blkdev_report_zones(struct block_device *bdev, sector_t sector,
419 		unsigned int nr_zones, report_zones_cb cb, void *data);
420 int blkdev_zone_mgmt(struct block_device *bdev, enum req_op op,
421 		sector_t sectors, sector_t nr_sectors);
422 int blk_revalidate_disk_zones(struct gendisk *disk);
423 
424 /*
425  * Independent access ranges: struct blk_independent_access_range describes
426  * a range of contiguous sectors that can be accessed using device command
427  * execution resources that are independent from the resources used for
428  * other access ranges. This is typically found with single-LUN multi-actuator
429  * HDDs where each access range is served by a different set of heads.
430  * The set of independent ranges supported by the device is defined using
431  * struct blk_independent_access_ranges. The independent ranges must not overlap
432  * and must include all sectors within the disk capacity (no sector holes
433  * allowed).
434  * For a device with multiple ranges, requests targeting sectors in different
435  * ranges can be executed in parallel. A request can straddle an access range
436  * boundary.
437  */
438 struct blk_independent_access_range {
439 	struct kobject		kobj;
440 	sector_t		sector;
441 	sector_t		nr_sectors;
442 };
443 
444 struct blk_independent_access_ranges {
445 	struct kobject				kobj;
446 	bool					sysfs_registered;
447 	unsigned int				nr_ia_ranges;
448 	struct blk_independent_access_range	ia_range[];
449 };
450 
451 struct request_queue {
452 	/*
453 	 * The queue owner gets to use this for whatever they like.
454 	 * ll_rw_blk doesn't touch it.
455 	 */
456 	void			*queuedata;
457 
458 	struct elevator_queue	*elevator;
459 
460 	const struct blk_mq_ops	*mq_ops;
461 
462 	/* sw queues */
463 	struct blk_mq_ctx __percpu	*queue_ctx;
464 
465 	/*
466 	 * various queue flags, see QUEUE_* below
467 	 */
468 	unsigned long		queue_flags;
469 
470 	unsigned int		rq_timeout;
471 
472 	unsigned int		queue_depth;
473 
474 	refcount_t		refs;
475 
476 	/* hw dispatch queues */
477 	unsigned int		nr_hw_queues;
478 	struct xarray		hctx_table;
479 
480 	struct percpu_ref	q_usage_counter;
481 	struct lock_class_key	io_lock_cls_key;
482 	struct lockdep_map	io_lockdep_map;
483 
484 	struct lock_class_key	q_lock_cls_key;
485 	struct lockdep_map	q_lockdep_map;
486 
487 	struct request		*last_merge;
488 
489 	spinlock_t		queue_lock;
490 
491 	int			quiesce_depth;
492 
493 	struct gendisk		*disk;
494 
495 	/*
496 	 * mq queue kobject
497 	 */
498 	struct kobject *mq_kobj;
499 
500 	struct queue_limits	limits;
501 
502 #ifdef CONFIG_PM
503 	struct device		*dev;
504 	enum rpm_status		rpm_status;
505 #endif
506 
507 	/*
508 	 * Number of contexts that have called blk_set_pm_only(). If this
509 	 * counter is above zero then only RQF_PM requests are processed.
510 	 */
511 	atomic_t		pm_only;
512 
513 	struct blk_queue_stats	*stats;
514 	struct rq_qos		*rq_qos;
515 	struct mutex		rq_qos_mutex;
516 
517 	/*
518 	 * ida allocated id for this queue.  Used to index queues from
519 	 * ioctx.
520 	 */
521 	int			id;
522 
523 	/*
524 	 * queue settings
525 	 */
526 	unsigned long		nr_requests;	/* Max # of requests */
527 
528 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
529 	struct blk_crypto_profile *crypto_profile;
530 	struct kobject *crypto_kobject;
531 #endif
532 
533 	struct timer_list	timeout;
534 	struct work_struct	timeout_work;
535 
536 	atomic_t		nr_active_requests_shared_tags;
537 
538 	struct blk_mq_tags	*sched_shared_tags;
539 
540 	struct list_head	icq_list;
541 #ifdef CONFIG_BLK_CGROUP
542 	DECLARE_BITMAP		(blkcg_pols, BLKCG_MAX_POLS);
543 	struct blkcg_gq		*root_blkg;
544 	struct list_head	blkg_list;
545 	struct mutex		blkcg_mutex;
546 #endif
547 
548 	int			node;
549 
550 	spinlock_t		requeue_lock;
551 	struct list_head	requeue_list;
552 	struct delayed_work	requeue_work;
553 
554 #ifdef CONFIG_BLK_DEV_IO_TRACE
555 	struct blk_trace __rcu	*blk_trace;
556 #endif
557 	/*
558 	 * for flush operations
559 	 */
560 	struct blk_flush_queue	*fq;
561 	struct list_head	flush_list;
562 
563 	/*
564 	 * Protects against I/O scheduler switching, particularly when
565 	 * updating q->elevator. Since the elevator update code path may
566 	 * also modify q->nr_requests and wbt latency, this lock also
567 	 * protects the sysfs attributes nr_requests and wbt_lat_usec.
568 	 * To ensure proper locking order during an elevator update, first
569 	 * freeze the queue, then acquire ->elevator_lock.
570 	 */
571 	struct mutex		elevator_lock;
572 
573 	struct mutex		sysfs_lock;
574 	/*
575 	 * Protects queue limits and also sysfs attribute read_ahead_kb.
576 	 */
577 	struct mutex		limits_lock;
578 
579 	/*
580 	 * for reusing dead hctx instance in case of updating
581 	 * nr_hw_queues
582 	 */
583 	struct list_head	unused_hctx_list;
584 	spinlock_t		unused_hctx_lock;
585 
586 	int			mq_freeze_depth;
587 
588 #ifdef CONFIG_BLK_DEV_THROTTLING
589 	/* Throttle data */
590 	struct throtl_data *td;
591 #endif
592 	struct rcu_head		rcu_head;
593 #ifdef CONFIG_LOCKDEP
594 	struct task_struct	*mq_freeze_owner;
595 	int			mq_freeze_owner_depth;
596 	/*
597 	 * Records disk & queue state in current context, used in unfreeze
598 	 * queue
599 	 */
600 	bool			mq_freeze_disk_dead;
601 	bool			mq_freeze_queue_dying;
602 #endif
603 	wait_queue_head_t	mq_freeze_wq;
604 	/*
605 	 * Protect concurrent access to q_usage_counter by
606 	 * percpu_ref_kill() and percpu_ref_reinit().
607 	 */
608 	struct mutex		mq_freeze_lock;
609 
610 	struct blk_mq_tag_set	*tag_set;
611 	struct list_head	tag_set_list;
612 
613 	struct dentry		*debugfs_dir;
614 	struct dentry		*sched_debugfs_dir;
615 	struct dentry		*rqos_debugfs_dir;
616 	/*
617 	 * Serializes all debugfs metadata operations using the above dentries.
618 	 */
619 	struct mutex		debugfs_mutex;
620 };
621 
622 /* Keep blk_queue_flag_name[] in sync with the definitions below */
623 enum {
624 	QUEUE_FLAG_DYING,		/* queue being torn down */
625 	QUEUE_FLAG_NOMERGES,		/* disable merge attempts */
626 	QUEUE_FLAG_SAME_COMP,		/* complete on same CPU-group */
627 	QUEUE_FLAG_FAIL_IO,		/* fake timeout */
628 	QUEUE_FLAG_NOXMERGES,		/* No extended merges */
629 	QUEUE_FLAG_SAME_FORCE,		/* force complete on same CPU */
630 	QUEUE_FLAG_INIT_DONE,		/* queue is initialized */
631 	QUEUE_FLAG_STATS,		/* track IO start and completion times */
632 	QUEUE_FLAG_REGISTERED,		/* queue has been registered to a disk */
633 	QUEUE_FLAG_QUIESCED,		/* queue has been quiesced */
634 	QUEUE_FLAG_RQ_ALLOC_TIME,	/* record rq->alloc_time_ns */
635 	QUEUE_FLAG_HCTX_ACTIVE,		/* at least one blk-mq hctx is active */
636 	QUEUE_FLAG_SQ_SCHED,		/* single queue style io dispatch */
637 	QUEUE_FLAG_MAX
638 };
639 
640 #define QUEUE_FLAG_MQ_DEFAULT	(1UL << QUEUE_FLAG_SAME_COMP)
641 
642 void blk_queue_flag_set(unsigned int flag, struct request_queue *q);
643 void blk_queue_flag_clear(unsigned int flag, struct request_queue *q);
644 
645 #define blk_queue_dying(q)	test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
646 #define blk_queue_init_done(q)	test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
647 #define blk_queue_nomerges(q)	test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
648 #define blk_queue_noxmerges(q)	\
649 	test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
650 #define blk_queue_nonrot(q)	(!((q)->limits.features & BLK_FEAT_ROTATIONAL))
651 #define blk_queue_io_stat(q)	((q)->limits.features & BLK_FEAT_IO_STAT)
652 #define blk_queue_passthrough_stat(q)	\
653 	((q)->limits.flags & BLK_FLAG_IOSTATS_PASSTHROUGH)
654 #define blk_queue_dax(q)	((q)->limits.features & BLK_FEAT_DAX)
655 #define blk_queue_pci_p2pdma(q)	((q)->limits.features & BLK_FEAT_PCI_P2PDMA)
656 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
657 #define blk_queue_rq_alloc_time(q)	\
658 	test_bit(QUEUE_FLAG_RQ_ALLOC_TIME, &(q)->queue_flags)
659 #else
660 #define blk_queue_rq_alloc_time(q)	false
661 #endif
662 
663 #define blk_noretry_request(rq) \
664 	((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
665 			     REQ_FAILFAST_DRIVER))
666 #define blk_queue_quiesced(q)	test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
667 #define blk_queue_pm_only(q)	atomic_read(&(q)->pm_only)
668 #define blk_queue_registered(q)	test_bit(QUEUE_FLAG_REGISTERED, &(q)->queue_flags)
669 #define blk_queue_sq_sched(q)	test_bit(QUEUE_FLAG_SQ_SCHED, &(q)->queue_flags)
670 #define blk_queue_skip_tagset_quiesce(q) \
671 	((q)->limits.features & BLK_FEAT_SKIP_TAGSET_QUIESCE)
672 
673 extern void blk_set_pm_only(struct request_queue *q);
674 extern void blk_clear_pm_only(struct request_queue *q);
675 
676 #define list_entry_rq(ptr)	list_entry((ptr), struct request, queuelist)
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 #ifdef CONFIG_PM
688 static inline enum rpm_status queue_rpm_status(struct request_queue *q)
689 {
690 	return q->rpm_status;
691 }
692 #else
693 static inline enum rpm_status queue_rpm_status(struct request_queue *q)
694 {
695 	return RPM_ACTIVE;
696 }
697 #endif
698 
699 static inline bool blk_queue_is_zoned(struct request_queue *q)
700 {
701 	return IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
702 		(q->limits.features & BLK_FEAT_ZONED);
703 }
704 
705 #ifdef CONFIG_BLK_DEV_ZONED
706 static inline unsigned int disk_nr_zones(struct gendisk *disk)
707 {
708 	return disk->nr_zones;
709 }
710 bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs);
711 #else /* CONFIG_BLK_DEV_ZONED */
712 static inline unsigned int disk_nr_zones(struct gendisk *disk)
713 {
714 	return 0;
715 }
716 static inline bool blk_zone_plug_bio(struct bio *bio, unsigned int nr_segs)
717 {
718 	return false;
719 }
720 #endif /* CONFIG_BLK_DEV_ZONED */
721 
722 static inline unsigned int disk_zone_no(struct gendisk *disk, sector_t sector)
723 {
724 	if (!blk_queue_is_zoned(disk->queue))
725 		return 0;
726 	return sector >> ilog2(disk->queue->limits.chunk_sectors);
727 }
728 
729 static inline unsigned int bdev_nr_zones(struct block_device *bdev)
730 {
731 	return disk_nr_zones(bdev->bd_disk);
732 }
733 
734 static inline unsigned int bdev_max_open_zones(struct block_device *bdev)
735 {
736 	return bdev->bd_disk->queue->limits.max_open_zones;
737 }
738 
739 static inline unsigned int bdev_max_active_zones(struct block_device *bdev)
740 {
741 	return bdev->bd_disk->queue->limits.max_active_zones;
742 }
743 
744 static inline unsigned int blk_queue_depth(struct request_queue *q)
745 {
746 	if (q->queue_depth)
747 		return q->queue_depth;
748 
749 	return q->nr_requests;
750 }
751 
752 /*
753  * default timeout for SG_IO if none specified
754  */
755 #define BLK_DEFAULT_SG_TIMEOUT	(60 * HZ)
756 #define BLK_MIN_SG_TIMEOUT	(7 * HZ)
757 
758 /* This should not be used directly - use rq_for_each_segment */
759 #define for_each_bio(_bio)		\
760 	for (; _bio; _bio = _bio->bi_next)
761 
762 int __must_check add_disk_fwnode(struct device *parent, struct gendisk *disk,
763 				 const struct attribute_group **groups,
764 				 struct fwnode_handle *fwnode);
765 int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
766 				 const struct attribute_group **groups);
767 static inline int __must_check add_disk(struct gendisk *disk)
768 {
769 	return device_add_disk(NULL, disk, NULL);
770 }
771 void del_gendisk(struct gendisk *gp);
772 void invalidate_disk(struct gendisk *disk);
773 void set_disk_ro(struct gendisk *disk, bool read_only);
774 void disk_uevent(struct gendisk *disk, enum kobject_action action);
775 
776 static inline u8 bdev_partno(const struct block_device *bdev)
777 {
778 	return atomic_read(&bdev->__bd_flags) & BD_PARTNO;
779 }
780 
781 static inline bool bdev_test_flag(const struct block_device *bdev, unsigned flag)
782 {
783 	return atomic_read(&bdev->__bd_flags) & flag;
784 }
785 
786 static inline void bdev_set_flag(struct block_device *bdev, unsigned flag)
787 {
788 	atomic_or(flag, &bdev->__bd_flags);
789 }
790 
791 static inline void bdev_clear_flag(struct block_device *bdev, unsigned flag)
792 {
793 	atomic_andnot(flag, &bdev->__bd_flags);
794 }
795 
796 static inline bool get_disk_ro(struct gendisk *disk)
797 {
798 	return bdev_test_flag(disk->part0, BD_READ_ONLY) ||
799 		test_bit(GD_READ_ONLY, &disk->state);
800 }
801 
802 static inline bool bdev_read_only(struct block_device *bdev)
803 {
804 	return bdev_test_flag(bdev, BD_READ_ONLY) || get_disk_ro(bdev->bd_disk);
805 }
806 
807 bool set_capacity_and_notify(struct gendisk *disk, sector_t size);
808 void disk_force_media_change(struct gendisk *disk);
809 void bdev_mark_dead(struct block_device *bdev, bool surprise);
810 
811 void add_disk_randomness(struct gendisk *disk) __latent_entropy;
812 void rand_initialize_disk(struct gendisk *disk);
813 
814 static inline sector_t get_start_sect(struct block_device *bdev)
815 {
816 	return bdev->bd_start_sect;
817 }
818 
819 static inline sector_t bdev_nr_sectors(struct block_device *bdev)
820 {
821 	return bdev->bd_nr_sectors;
822 }
823 
824 static inline loff_t bdev_nr_bytes(struct block_device *bdev)
825 {
826 	return (loff_t)bdev_nr_sectors(bdev) << SECTOR_SHIFT;
827 }
828 
829 static inline sector_t get_capacity(struct gendisk *disk)
830 {
831 	return bdev_nr_sectors(disk->part0);
832 }
833 
834 static inline u64 sb_bdev_nr_blocks(struct super_block *sb)
835 {
836 	return bdev_nr_sectors(sb->s_bdev) >>
837 		(sb->s_blocksize_bits - SECTOR_SHIFT);
838 }
839 
840 int bdev_disk_changed(struct gendisk *disk, bool invalidate);
841 
842 void put_disk(struct gendisk *disk);
843 struct gendisk *__blk_alloc_disk(struct queue_limits *lim, int node,
844 		struct lock_class_key *lkclass);
845 
846 /**
847  * blk_alloc_disk - allocate a gendisk structure
848  * @lim: queue limits to be used for this disk.
849  * @node_id: numa node to allocate on
850  *
851  * Allocate and pre-initialize a gendisk structure for use with BIO based
852  * drivers.
853  *
854  * Returns an ERR_PTR on error, else the allocated disk.
855  *
856  * Context: can sleep
857  */
858 #define blk_alloc_disk(lim, node_id)					\
859 ({									\
860 	static struct lock_class_key __key;				\
861 									\
862 	__blk_alloc_disk(lim, node_id, &__key);				\
863 })
864 
865 int __register_blkdev(unsigned int major, const char *name,
866 		void (*probe)(dev_t devt));
867 #define register_blkdev(major, name) \
868 	__register_blkdev(major, name, NULL)
869 void unregister_blkdev(unsigned int major, const char *name);
870 
871 bool disk_check_media_change(struct gendisk *disk);
872 void set_capacity(struct gendisk *disk, sector_t size);
873 
874 #ifdef CONFIG_BLOCK_HOLDER_DEPRECATED
875 int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
876 void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk);
877 #else
878 static inline int bd_link_disk_holder(struct block_device *bdev,
879 				      struct gendisk *disk)
880 {
881 	return 0;
882 }
883 static inline void bd_unlink_disk_holder(struct block_device *bdev,
884 					 struct gendisk *disk)
885 {
886 }
887 #endif /* CONFIG_BLOCK_HOLDER_DEPRECATED */
888 
889 dev_t part_devt(struct gendisk *disk, u8 partno);
890 void inc_diskseq(struct gendisk *disk);
891 void blk_request_module(dev_t devt);
892 
893 extern int blk_register_queue(struct gendisk *disk);
894 extern void blk_unregister_queue(struct gendisk *disk);
895 void submit_bio_noacct(struct bio *bio);
896 struct bio *bio_split_to_limits(struct bio *bio);
897 
898 extern int blk_lld_busy(struct request_queue *q);
899 extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
900 extern void blk_queue_exit(struct request_queue *q);
901 extern void blk_sync_queue(struct request_queue *q);
902 
903 /* Helper to convert REQ_OP_XXX to its string format XXX */
904 extern const char *blk_op_str(enum req_op op);
905 
906 int blk_status_to_errno(blk_status_t status);
907 blk_status_t errno_to_blk_status(int errno);
908 const char *blk_status_to_str(blk_status_t status);
909 
910 /* only poll the hardware once, don't continue until a completion was found */
911 #define BLK_POLL_ONESHOT		(1 << 0)
912 int bio_poll(struct bio *bio, struct io_comp_batch *iob, unsigned int flags);
913 int iocb_bio_iopoll(struct kiocb *kiocb, struct io_comp_batch *iob,
914 			unsigned int flags);
915 
916 static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
917 {
918 	return bdev->bd_queue;	/* this is never NULL */
919 }
920 
921 /* Helper to convert BLK_ZONE_ZONE_XXX to its string format XXX */
922 const char *blk_zone_cond_str(enum blk_zone_cond zone_cond);
923 
924 static inline unsigned int bio_zone_no(struct bio *bio)
925 {
926 	return disk_zone_no(bio->bi_bdev->bd_disk, bio->bi_iter.bi_sector);
927 }
928 
929 static inline bool bio_straddles_zones(struct bio *bio)
930 {
931 	return bio_sectors(bio) &&
932 		bio_zone_no(bio) !=
933 		disk_zone_no(bio->bi_bdev->bd_disk, bio_end_sector(bio) - 1);
934 }
935 
936 /*
937  * Return how much within the boundary is left to be used for I/O at a given
938  * offset.
939  */
940 static inline unsigned int blk_boundary_sectors_left(sector_t offset,
941 		unsigned int boundary_sectors)
942 {
943 	if (unlikely(!is_power_of_2(boundary_sectors)))
944 		return boundary_sectors - sector_div(offset, boundary_sectors);
945 	return boundary_sectors - (offset & (boundary_sectors - 1));
946 }
947 
948 /**
949  * queue_limits_start_update - start an atomic update of queue limits
950  * @q:		queue to update
951  *
952  * This functions starts an atomic update of the queue limits.  It takes a lock
953  * to prevent other updates and returns a snapshot of the current limits that
954  * the caller can modify.  The caller must call queue_limits_commit_update()
955  * to finish the update.
956  *
957  * Context: process context.
958  */
959 static inline struct queue_limits
960 queue_limits_start_update(struct request_queue *q)
961 {
962 	mutex_lock(&q->limits_lock);
963 	return q->limits;
964 }
965 int queue_limits_commit_update_frozen(struct request_queue *q,
966 		struct queue_limits *lim);
967 int queue_limits_commit_update(struct request_queue *q,
968 		struct queue_limits *lim);
969 int queue_limits_set(struct request_queue *q, struct queue_limits *lim);
970 int blk_validate_limits(struct queue_limits *lim);
971 
972 /**
973  * queue_limits_cancel_update - cancel an atomic update of queue limits
974  * @q:		queue to update
975  *
976  * This functions cancels an atomic update of the queue limits started by
977  * queue_limits_start_update() and should be used when an error occurs after
978  * starting update.
979  */
980 static inline void queue_limits_cancel_update(struct request_queue *q)
981 {
982 	mutex_unlock(&q->limits_lock);
983 }
984 
985 /*
986  * These helpers are for drivers that have sloppy feature negotiation and might
987  * have to disable DISCARD, WRITE_ZEROES or SECURE_DISCARD from the I/O
988  * completion handler when the device returned an indicator that the respective
989  * feature is not actually supported.  They are racy and the driver needs to
990  * cope with that.  Try to avoid this scheme if you can.
991  */
992 static inline void blk_queue_disable_discard(struct request_queue *q)
993 {
994 	q->limits.max_discard_sectors = 0;
995 }
996 
997 static inline void blk_queue_disable_secure_erase(struct request_queue *q)
998 {
999 	q->limits.max_secure_erase_sectors = 0;
1000 }
1001 
1002 static inline void blk_queue_disable_write_zeroes(struct request_queue *q)
1003 {
1004 	q->limits.max_write_zeroes_sectors = 0;
1005 }
1006 
1007 /*
1008  * Access functions for manipulating queue properties
1009  */
1010 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth);
1011 extern void blk_set_stacking_limits(struct queue_limits *lim);
1012 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1013 			    sector_t offset);
1014 void queue_limits_stack_bdev(struct queue_limits *t, struct block_device *bdev,
1015 		sector_t offset, const char *pfx);
1016 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1017 
1018 struct blk_independent_access_ranges *
1019 disk_alloc_independent_access_ranges(struct gendisk *disk, int nr_ia_ranges);
1020 void disk_set_independent_access_ranges(struct gendisk *disk,
1021 				struct blk_independent_access_ranges *iars);
1022 
1023 bool __must_check blk_get_queue(struct request_queue *);
1024 extern void blk_put_queue(struct request_queue *);
1025 
1026 void blk_mark_disk_dead(struct gendisk *disk);
1027 
1028 struct rq_list {
1029 	struct request *head;
1030 	struct request *tail;
1031 };
1032 
1033 #ifdef CONFIG_BLOCK
1034 /*
1035  * blk_plug permits building a queue of related requests by holding the I/O
1036  * fragments for a short period. This allows merging of sequential requests
1037  * into single larger request. As the requests are moved from a per-task list to
1038  * the device's request_queue in a batch, this results in improved scalability
1039  * as the lock contention for request_queue lock is reduced.
1040  *
1041  * It is ok not to disable preemption when adding the request to the plug list
1042  * or when attempting a merge. For details, please see schedule() where
1043  * blk_flush_plug() is called.
1044  */
1045 struct blk_plug {
1046 	struct rq_list mq_list; /* blk-mq requests */
1047 
1048 	/* if ios_left is > 1, we can batch tag/rq allocations */
1049 	struct rq_list cached_rqs;
1050 	u64 cur_ktime;
1051 	unsigned short nr_ios;
1052 
1053 	unsigned short rq_count;
1054 
1055 	bool multiple_queues;
1056 	bool has_elevator;
1057 
1058 	struct list_head cb_list; /* md requires an unplug callback */
1059 };
1060 
1061 struct blk_plug_cb;
1062 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1063 struct blk_plug_cb {
1064 	struct list_head list;
1065 	blk_plug_cb_fn callback;
1066 	void *data;
1067 };
1068 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1069 					     void *data, int size);
1070 extern void blk_start_plug(struct blk_plug *);
1071 extern void blk_start_plug_nr_ios(struct blk_plug *, unsigned short);
1072 extern void blk_finish_plug(struct blk_plug *);
1073 
1074 void __blk_flush_plug(struct blk_plug *plug, bool from_schedule);
1075 static inline void blk_flush_plug(struct blk_plug *plug, bool async)
1076 {
1077 	if (plug)
1078 		__blk_flush_plug(plug, async);
1079 }
1080 
1081 /*
1082  * tsk == current here
1083  */
1084 static inline void blk_plug_invalidate_ts(struct task_struct *tsk)
1085 {
1086 	struct blk_plug *plug = tsk->plug;
1087 
1088 	if (plug)
1089 		plug->cur_ktime = 0;
1090 	current->flags &= ~PF_BLOCK_TS;
1091 }
1092 
1093 int blkdev_issue_flush(struct block_device *bdev);
1094 long nr_blockdev_pages(void);
1095 #else /* CONFIG_BLOCK */
1096 struct blk_plug {
1097 };
1098 
1099 static inline void blk_start_plug_nr_ios(struct blk_plug *plug,
1100 					 unsigned short nr_ios)
1101 {
1102 }
1103 
1104 static inline void blk_start_plug(struct blk_plug *plug)
1105 {
1106 }
1107 
1108 static inline void blk_finish_plug(struct blk_plug *plug)
1109 {
1110 }
1111 
1112 static inline void blk_flush_plug(struct blk_plug *plug, bool async)
1113 {
1114 }
1115 
1116 static inline void blk_plug_invalidate_ts(struct task_struct *tsk)
1117 {
1118 }
1119 
1120 static inline int blkdev_issue_flush(struct block_device *bdev)
1121 {
1122 	return 0;
1123 }
1124 
1125 static inline long nr_blockdev_pages(void)
1126 {
1127 	return 0;
1128 }
1129 #endif /* CONFIG_BLOCK */
1130 
1131 extern void blk_io_schedule(void);
1132 
1133 int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1134 		sector_t nr_sects, gfp_t gfp_mask);
1135 int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1136 		sector_t nr_sects, gfp_t gfp_mask, struct bio **biop);
1137 int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
1138 		sector_t nr_sects, gfp_t gfp);
1139 
1140 #define BLKDEV_ZERO_NOUNMAP	(1 << 0)  /* do not free blocks */
1141 #define BLKDEV_ZERO_NOFALLBACK	(1 << 1)  /* don't write explicit zeroes */
1142 #define BLKDEV_ZERO_KILLABLE	(1 << 2)  /* interruptible by fatal signals */
1143 
1144 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1145 		sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
1146 		unsigned flags);
1147 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1148 		sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
1149 
1150 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1151 		sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1152 {
1153 	return blkdev_issue_discard(sb->s_bdev,
1154 				    block << (sb->s_blocksize_bits -
1155 					      SECTOR_SHIFT),
1156 				    nr_blocks << (sb->s_blocksize_bits -
1157 						  SECTOR_SHIFT),
1158 				    gfp_mask);
1159 }
1160 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1161 		sector_t nr_blocks, gfp_t gfp_mask)
1162 {
1163 	return blkdev_issue_zeroout(sb->s_bdev,
1164 				    block << (sb->s_blocksize_bits -
1165 					      SECTOR_SHIFT),
1166 				    nr_blocks << (sb->s_blocksize_bits -
1167 						  SECTOR_SHIFT),
1168 				    gfp_mask, 0);
1169 }
1170 
1171 static inline bool bdev_is_partition(struct block_device *bdev)
1172 {
1173 	return bdev_partno(bdev) != 0;
1174 }
1175 
1176 enum blk_default_limits {
1177 	BLK_MAX_SEGMENTS	= 128,
1178 	BLK_SAFE_MAX_SECTORS	= 255,
1179 	BLK_MAX_SEGMENT_SIZE	= 65536,
1180 	BLK_SEG_BOUNDARY_MASK	= 0xFFFFFFFFUL,
1181 };
1182 
1183 /*
1184  * Default upper limit for the software max_sectors limit used for
1185  * regular file system I/O.  This can be increased through sysfs.
1186  *
1187  * Not to be confused with the max_hw_sector limit that is entirely
1188  * controlled by the driver, usually based on hardware limits.
1189  */
1190 #define BLK_DEF_MAX_SECTORS_CAP	2560u
1191 
1192 static inline struct queue_limits *bdev_limits(struct block_device *bdev)
1193 {
1194 	return &bdev_get_queue(bdev)->limits;
1195 }
1196 
1197 static inline unsigned long queue_segment_boundary(const struct request_queue *q)
1198 {
1199 	return q->limits.seg_boundary_mask;
1200 }
1201 
1202 static inline unsigned long queue_virt_boundary(const struct request_queue *q)
1203 {
1204 	return q->limits.virt_boundary_mask;
1205 }
1206 
1207 static inline unsigned int queue_max_sectors(const struct request_queue *q)
1208 {
1209 	return q->limits.max_sectors;
1210 }
1211 
1212 static inline unsigned int queue_max_bytes(struct request_queue *q)
1213 {
1214 	return min_t(unsigned int, queue_max_sectors(q), INT_MAX >> 9) << 9;
1215 }
1216 
1217 static inline unsigned int queue_max_hw_sectors(const struct request_queue *q)
1218 {
1219 	return q->limits.max_hw_sectors;
1220 }
1221 
1222 static inline unsigned short queue_max_segments(const struct request_queue *q)
1223 {
1224 	return q->limits.max_segments;
1225 }
1226 
1227 static inline unsigned short queue_max_discard_segments(const struct request_queue *q)
1228 {
1229 	return q->limits.max_discard_segments;
1230 }
1231 
1232 static inline unsigned int queue_max_segment_size(const struct request_queue *q)
1233 {
1234 	return q->limits.max_segment_size;
1235 }
1236 
1237 static inline bool queue_emulates_zone_append(struct request_queue *q)
1238 {
1239 	return blk_queue_is_zoned(q) && !q->limits.max_hw_zone_append_sectors;
1240 }
1241 
1242 static inline bool bdev_emulates_zone_append(struct block_device *bdev)
1243 {
1244 	return queue_emulates_zone_append(bdev_get_queue(bdev));
1245 }
1246 
1247 static inline unsigned int
1248 bdev_max_zone_append_sectors(struct block_device *bdev)
1249 {
1250 	return bdev_limits(bdev)->max_zone_append_sectors;
1251 }
1252 
1253 static inline unsigned int bdev_max_segments(struct block_device *bdev)
1254 {
1255 	return queue_max_segments(bdev_get_queue(bdev));
1256 }
1257 
1258 static inline unsigned queue_logical_block_size(const struct request_queue *q)
1259 {
1260 	return q->limits.logical_block_size;
1261 }
1262 
1263 static inline unsigned int bdev_logical_block_size(struct block_device *bdev)
1264 {
1265 	return queue_logical_block_size(bdev_get_queue(bdev));
1266 }
1267 
1268 static inline unsigned int queue_physical_block_size(const struct request_queue *q)
1269 {
1270 	return q->limits.physical_block_size;
1271 }
1272 
1273 static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1274 {
1275 	return queue_physical_block_size(bdev_get_queue(bdev));
1276 }
1277 
1278 static inline unsigned int queue_io_min(const struct request_queue *q)
1279 {
1280 	return q->limits.io_min;
1281 }
1282 
1283 static inline unsigned int bdev_io_min(struct block_device *bdev)
1284 {
1285 	return queue_io_min(bdev_get_queue(bdev));
1286 }
1287 
1288 static inline unsigned int queue_io_opt(const struct request_queue *q)
1289 {
1290 	return q->limits.io_opt;
1291 }
1292 
1293 static inline unsigned int bdev_io_opt(struct block_device *bdev)
1294 {
1295 	return queue_io_opt(bdev_get_queue(bdev));
1296 }
1297 
1298 static inline unsigned int
1299 queue_zone_write_granularity(const struct request_queue *q)
1300 {
1301 	return q->limits.zone_write_granularity;
1302 }
1303 
1304 static inline unsigned int
1305 bdev_zone_write_granularity(struct block_device *bdev)
1306 {
1307 	return queue_zone_write_granularity(bdev_get_queue(bdev));
1308 }
1309 
1310 int bdev_alignment_offset(struct block_device *bdev);
1311 unsigned int bdev_discard_alignment(struct block_device *bdev);
1312 
1313 static inline unsigned int bdev_max_discard_sectors(struct block_device *bdev)
1314 {
1315 	return bdev_limits(bdev)->max_discard_sectors;
1316 }
1317 
1318 static inline unsigned int bdev_discard_granularity(struct block_device *bdev)
1319 {
1320 	return bdev_limits(bdev)->discard_granularity;
1321 }
1322 
1323 static inline unsigned int
1324 bdev_max_secure_erase_sectors(struct block_device *bdev)
1325 {
1326 	return bdev_limits(bdev)->max_secure_erase_sectors;
1327 }
1328 
1329 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
1330 {
1331 	return bdev_limits(bdev)->max_write_zeroes_sectors;
1332 }
1333 
1334 static inline bool bdev_nonrot(struct block_device *bdev)
1335 {
1336 	return blk_queue_nonrot(bdev_get_queue(bdev));
1337 }
1338 
1339 static inline bool bdev_synchronous(struct block_device *bdev)
1340 {
1341 	return bdev->bd_disk->queue->limits.features & BLK_FEAT_SYNCHRONOUS;
1342 }
1343 
1344 static inline bool bdev_stable_writes(struct block_device *bdev)
1345 {
1346 	struct request_queue *q = bdev_get_queue(bdev);
1347 
1348 	if (IS_ENABLED(CONFIG_BLK_DEV_INTEGRITY) &&
1349 	    q->limits.integrity.csum_type != BLK_INTEGRITY_CSUM_NONE)
1350 		return true;
1351 	return q->limits.features & BLK_FEAT_STABLE_WRITES;
1352 }
1353 
1354 static inline bool blk_queue_write_cache(struct request_queue *q)
1355 {
1356 	return (q->limits.features & BLK_FEAT_WRITE_CACHE) &&
1357 		!(q->limits.flags & BLK_FLAG_WRITE_CACHE_DISABLED);
1358 }
1359 
1360 static inline bool bdev_write_cache(struct block_device *bdev)
1361 {
1362 	return blk_queue_write_cache(bdev_get_queue(bdev));
1363 }
1364 
1365 static inline bool bdev_fua(struct block_device *bdev)
1366 {
1367 	return bdev_limits(bdev)->features & BLK_FEAT_FUA;
1368 }
1369 
1370 static inline bool bdev_nowait(struct block_device *bdev)
1371 {
1372 	return bdev->bd_disk->queue->limits.features & BLK_FEAT_NOWAIT;
1373 }
1374 
1375 static inline bool bdev_is_zoned(struct block_device *bdev)
1376 {
1377 	return blk_queue_is_zoned(bdev_get_queue(bdev));
1378 }
1379 
1380 static inline unsigned int bdev_zone_no(struct block_device *bdev, sector_t sec)
1381 {
1382 	return disk_zone_no(bdev->bd_disk, sec);
1383 }
1384 
1385 static inline sector_t bdev_zone_sectors(struct block_device *bdev)
1386 {
1387 	struct request_queue *q = bdev_get_queue(bdev);
1388 
1389 	if (!blk_queue_is_zoned(q))
1390 		return 0;
1391 	return q->limits.chunk_sectors;
1392 }
1393 
1394 static inline sector_t bdev_offset_from_zone_start(struct block_device *bdev,
1395 						   sector_t sector)
1396 {
1397 	return sector & (bdev_zone_sectors(bdev) - 1);
1398 }
1399 
1400 static inline sector_t bio_offset_from_zone_start(struct bio *bio)
1401 {
1402 	return bdev_offset_from_zone_start(bio->bi_bdev,
1403 					   bio->bi_iter.bi_sector);
1404 }
1405 
1406 static inline bool bdev_is_zone_start(struct block_device *bdev,
1407 				      sector_t sector)
1408 {
1409 	return bdev_offset_from_zone_start(bdev, sector) == 0;
1410 }
1411 
1412 /**
1413  * bdev_zone_is_seq - check if a sector belongs to a sequential write zone
1414  * @bdev:	block device to check
1415  * @sector:	sector number
1416  *
1417  * Check if @sector on @bdev is contained in a sequential write required zone.
1418  */
1419 static inline bool bdev_zone_is_seq(struct block_device *bdev, sector_t sector)
1420 {
1421 	bool is_seq = false;
1422 
1423 #if IS_ENABLED(CONFIG_BLK_DEV_ZONED)
1424 	if (bdev_is_zoned(bdev)) {
1425 		struct gendisk *disk = bdev->bd_disk;
1426 		unsigned long *bitmap;
1427 
1428 		rcu_read_lock();
1429 		bitmap = rcu_dereference(disk->conv_zones_bitmap);
1430 		is_seq = !bitmap ||
1431 			!test_bit(disk_zone_no(disk, sector), bitmap);
1432 		rcu_read_unlock();
1433 	}
1434 #endif
1435 
1436 	return is_seq;
1437 }
1438 
1439 int blk_zone_issue_zeroout(struct block_device *bdev, sector_t sector,
1440 			   sector_t nr_sects, gfp_t gfp_mask);
1441 
1442 static inline unsigned int queue_dma_alignment(const struct request_queue *q)
1443 {
1444 	return q->limits.dma_alignment;
1445 }
1446 
1447 static inline unsigned int
1448 queue_atomic_write_unit_max_bytes(const struct request_queue *q)
1449 {
1450 	return q->limits.atomic_write_unit_max;
1451 }
1452 
1453 static inline unsigned int
1454 queue_atomic_write_unit_min_bytes(const struct request_queue *q)
1455 {
1456 	return q->limits.atomic_write_unit_min;
1457 }
1458 
1459 static inline unsigned int
1460 queue_atomic_write_boundary_bytes(const struct request_queue *q)
1461 {
1462 	return q->limits.atomic_write_boundary_sectors << SECTOR_SHIFT;
1463 }
1464 
1465 static inline unsigned int
1466 queue_atomic_write_max_bytes(const struct request_queue *q)
1467 {
1468 	return q->limits.atomic_write_max_sectors << SECTOR_SHIFT;
1469 }
1470 
1471 static inline unsigned int bdev_dma_alignment(struct block_device *bdev)
1472 {
1473 	return queue_dma_alignment(bdev_get_queue(bdev));
1474 }
1475 
1476 static inline bool bdev_iter_is_aligned(struct block_device *bdev,
1477 					struct iov_iter *iter)
1478 {
1479 	return iov_iter_is_aligned(iter, bdev_dma_alignment(bdev),
1480 				   bdev_logical_block_size(bdev) - 1);
1481 }
1482 
1483 static inline unsigned int
1484 blk_lim_dma_alignment_and_pad(struct queue_limits *lim)
1485 {
1486 	return lim->dma_alignment | lim->dma_pad_mask;
1487 }
1488 
1489 static inline bool blk_rq_aligned(struct request_queue *q, unsigned long addr,
1490 				 unsigned int len)
1491 {
1492 	unsigned int alignment = blk_lim_dma_alignment_and_pad(&q->limits);
1493 
1494 	return !(addr & alignment) && !(len & alignment);
1495 }
1496 
1497 /* assumes size > 256 */
1498 static inline unsigned int blksize_bits(unsigned int size)
1499 {
1500 	return order_base_2(size >> SECTOR_SHIFT) + SECTOR_SHIFT;
1501 }
1502 
1503 int kblockd_schedule_work(struct work_struct *work);
1504 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1505 
1506 #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1507 	MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1508 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1509 	MODULE_ALIAS("block-major-" __stringify(major) "-*")
1510 
1511 #ifdef CONFIG_BLK_INLINE_ENCRYPTION
1512 
1513 bool blk_crypto_register(struct blk_crypto_profile *profile,
1514 			 struct request_queue *q);
1515 
1516 #else /* CONFIG_BLK_INLINE_ENCRYPTION */
1517 
1518 static inline bool blk_crypto_register(struct blk_crypto_profile *profile,
1519 				       struct request_queue *q)
1520 {
1521 	return true;
1522 }
1523 
1524 #endif /* CONFIG_BLK_INLINE_ENCRYPTION */
1525 
1526 enum blk_unique_id {
1527 	/* these match the Designator Types specified in SPC */
1528 	BLK_UID_T10	= 1,
1529 	BLK_UID_EUI64	= 2,
1530 	BLK_UID_NAA	= 3,
1531 };
1532 
1533 struct block_device_operations {
1534 	void (*submit_bio)(struct bio *bio);
1535 	int (*poll_bio)(struct bio *bio, struct io_comp_batch *iob,
1536 			unsigned int flags);
1537 	int (*open)(struct gendisk *disk, blk_mode_t mode);
1538 	void (*release)(struct gendisk *disk);
1539 	int (*ioctl)(struct block_device *bdev, blk_mode_t mode,
1540 			unsigned cmd, unsigned long arg);
1541 	int (*compat_ioctl)(struct block_device *bdev, blk_mode_t mode,
1542 			unsigned cmd, unsigned long arg);
1543 	unsigned int (*check_events) (struct gendisk *disk,
1544 				      unsigned int clearing);
1545 	void (*unlock_native_capacity) (struct gendisk *);
1546 	int (*getgeo)(struct block_device *, struct hd_geometry *);
1547 	int (*set_read_only)(struct block_device *bdev, bool ro);
1548 	void (*free_disk)(struct gendisk *disk);
1549 	/* this callback is with swap_lock and sometimes page table lock held */
1550 	void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1551 	int (*report_zones)(struct gendisk *, sector_t sector,
1552 			unsigned int nr_zones, report_zones_cb cb, void *data);
1553 	char *(*devnode)(struct gendisk *disk, umode_t *mode);
1554 	/* returns the length of the identifier or a negative errno: */
1555 	int (*get_unique_id)(struct gendisk *disk, u8 id[16],
1556 			enum blk_unique_id id_type);
1557 	struct module *owner;
1558 	const struct pr_ops *pr_ops;
1559 
1560 	/*
1561 	 * Special callback for probing GPT entry at a given sector.
1562 	 * Needed by Android devices, used by GPT scanner and MMC blk
1563 	 * driver.
1564 	 */
1565 	int (*alternative_gpt_sector)(struct gendisk *disk, sector_t *sector);
1566 };
1567 
1568 #ifdef CONFIG_COMPAT
1569 extern int blkdev_compat_ptr_ioctl(struct block_device *, blk_mode_t,
1570 				      unsigned int, unsigned long);
1571 #else
1572 #define blkdev_compat_ptr_ioctl NULL
1573 #endif
1574 
1575 static inline void blk_wake_io_task(struct task_struct *waiter)
1576 {
1577 	/*
1578 	 * If we're polling, the task itself is doing the completions. For
1579 	 * that case, we don't need to signal a wakeup, it's enough to just
1580 	 * mark us as RUNNING.
1581 	 */
1582 	if (waiter == current)
1583 		__set_current_state(TASK_RUNNING);
1584 	else
1585 		wake_up_process(waiter);
1586 }
1587 
1588 unsigned long bdev_start_io_acct(struct block_device *bdev, enum req_op op,
1589 				 unsigned long start_time);
1590 void bdev_end_io_acct(struct block_device *bdev, enum req_op op,
1591 		      unsigned int sectors, unsigned long start_time);
1592 
1593 unsigned long bio_start_io_acct(struct bio *bio);
1594 void bio_end_io_acct_remapped(struct bio *bio, unsigned long start_time,
1595 		struct block_device *orig_bdev);
1596 
1597 /**
1598  * bio_end_io_acct - end I/O accounting for bio based drivers
1599  * @bio:	bio to end account for
1600  * @start_time:	start time returned by bio_start_io_acct()
1601  */
1602 static inline void bio_end_io_acct(struct bio *bio, unsigned long start_time)
1603 {
1604 	return bio_end_io_acct_remapped(bio, start_time, bio->bi_bdev);
1605 }
1606 
1607 int set_blocksize(struct file *file, int size);
1608 
1609 int lookup_bdev(const char *pathname, dev_t *dev);
1610 
1611 void blkdev_show(struct seq_file *seqf, off_t offset);
1612 
1613 #define BDEVNAME_SIZE	32	/* Largest string for a blockdev identifier */
1614 #define BDEVT_SIZE	10	/* Largest string for MAJ:MIN for blkdev */
1615 #ifdef CONFIG_BLOCK
1616 #define BLKDEV_MAJOR_MAX	512
1617 #else
1618 #define BLKDEV_MAJOR_MAX	0
1619 #endif
1620 
1621 struct blk_holder_ops {
1622 	void (*mark_dead)(struct block_device *bdev, bool surprise);
1623 
1624 	/*
1625 	 * Sync the file system mounted on the block device.
1626 	 */
1627 	void (*sync)(struct block_device *bdev);
1628 
1629 	/*
1630 	 * Freeze the file system mounted on the block device.
1631 	 */
1632 	int (*freeze)(struct block_device *bdev);
1633 
1634 	/*
1635 	 * Thaw the file system mounted on the block device.
1636 	 */
1637 	int (*thaw)(struct block_device *bdev);
1638 };
1639 
1640 /*
1641  * For filesystems using @fs_holder_ops, the @holder argument passed to
1642  * helpers used to open and claim block devices via
1643  * bd_prepare_to_claim() must point to a superblock.
1644  */
1645 extern const struct blk_holder_ops fs_holder_ops;
1646 
1647 /*
1648  * Return the correct open flags for blkdev_get_by_* for super block flags
1649  * as stored in sb->s_flags.
1650  */
1651 #define sb_open_mode(flags) \
1652 	(BLK_OPEN_READ | BLK_OPEN_RESTRICT_WRITES | \
1653 	 (((flags) & SB_RDONLY) ? 0 : BLK_OPEN_WRITE))
1654 
1655 struct file *bdev_file_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
1656 		const struct blk_holder_ops *hops);
1657 struct file *bdev_file_open_by_path(const char *path, blk_mode_t mode,
1658 		void *holder, const struct blk_holder_ops *hops);
1659 int bd_prepare_to_claim(struct block_device *bdev, void *holder,
1660 		const struct blk_holder_ops *hops);
1661 void bd_abort_claiming(struct block_device *bdev, void *holder);
1662 
1663 /* just for blk-cgroup, don't use elsewhere */
1664 struct block_device *blkdev_get_no_open(dev_t dev);
1665 void blkdev_put_no_open(struct block_device *bdev);
1666 
1667 struct block_device *I_BDEV(struct inode *inode);
1668 struct block_device *file_bdev(struct file *bdev_file);
1669 bool disk_live(struct gendisk *disk);
1670 unsigned int block_size(struct block_device *bdev);
1671 
1672 #ifdef CONFIG_BLOCK
1673 void invalidate_bdev(struct block_device *bdev);
1674 int sync_blockdev(struct block_device *bdev);
1675 int sync_blockdev_range(struct block_device *bdev, loff_t lstart, loff_t lend);
1676 int sync_blockdev_nowait(struct block_device *bdev);
1677 void sync_bdevs(bool wait);
1678 void bdev_statx(struct path *, struct kstat *, u32);
1679 void printk_all_partitions(void);
1680 int __init early_lookup_bdev(const char *pathname, dev_t *dev);
1681 #else
1682 static inline void invalidate_bdev(struct block_device *bdev)
1683 {
1684 }
1685 static inline int sync_blockdev(struct block_device *bdev)
1686 {
1687 	return 0;
1688 }
1689 static inline int sync_blockdev_nowait(struct block_device *bdev)
1690 {
1691 	return 0;
1692 }
1693 static inline void sync_bdevs(bool wait)
1694 {
1695 }
1696 static inline void bdev_statx(struct path *path, struct kstat *stat,
1697 				u32 request_mask)
1698 {
1699 }
1700 static inline void printk_all_partitions(void)
1701 {
1702 }
1703 static inline int early_lookup_bdev(const char *pathname, dev_t *dev)
1704 {
1705 	return -EINVAL;
1706 }
1707 #endif /* CONFIG_BLOCK */
1708 
1709 int bdev_freeze(struct block_device *bdev);
1710 int bdev_thaw(struct block_device *bdev);
1711 void bdev_fput(struct file *bdev_file);
1712 
1713 struct io_comp_batch {
1714 	struct rq_list req_list;
1715 	bool need_ts;
1716 	void (*complete)(struct io_comp_batch *);
1717 };
1718 
1719 static inline bool blk_atomic_write_start_sect_aligned(sector_t sector,
1720 						struct queue_limits *limits)
1721 {
1722 	unsigned int alignment = max(limits->atomic_write_hw_unit_min,
1723 				limits->atomic_write_hw_boundary);
1724 
1725 	return IS_ALIGNED(sector, alignment >> SECTOR_SHIFT);
1726 }
1727 
1728 static inline bool bdev_can_atomic_write(struct block_device *bdev)
1729 {
1730 	struct request_queue *bd_queue = bdev->bd_queue;
1731 	struct queue_limits *limits = &bd_queue->limits;
1732 
1733 	if (!limits->atomic_write_unit_min)
1734 		return false;
1735 
1736 	if (bdev_is_partition(bdev))
1737 		return blk_atomic_write_start_sect_aligned(bdev->bd_start_sect,
1738 							limits);
1739 
1740 	return true;
1741 }
1742 
1743 static inline unsigned int
1744 bdev_atomic_write_unit_min_bytes(struct block_device *bdev)
1745 {
1746 	if (!bdev_can_atomic_write(bdev))
1747 		return 0;
1748 	return queue_atomic_write_unit_min_bytes(bdev_get_queue(bdev));
1749 }
1750 
1751 static inline unsigned int
1752 bdev_atomic_write_unit_max_bytes(struct block_device *bdev)
1753 {
1754 	if (!bdev_can_atomic_write(bdev))
1755 		return 0;
1756 	return queue_atomic_write_unit_max_bytes(bdev_get_queue(bdev));
1757 }
1758 
1759 #define DEFINE_IO_COMP_BATCH(name)	struct io_comp_batch name = { }
1760 
1761 #endif /* _LINUX_BLKDEV_H */
1762