projects/linux·blob v4.19-rc4 · refs

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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
8#ifdef CONFIG_BLOCK
9
10#include <linux/major.h>
11#include <linux/genhd.h>
12#include <linux/list.h>
13#include <linux/llist.h>
14#include <linux/timer.h>
15#include <linux/workqueue.h>
16#include <linux/pagemap.h>
17#include <linux/backing-dev-defs.h>
18#include <linux/wait.h>
19#include <linux/mempool.h>
20#include <linux/pfn.h>
21#include <linux/bio.h>
22#include <linux/stringify.h>
23#include <linux/gfp.h>
24#include <linux/bsg.h>
25#include <linux/smp.h>
26#include <linux/rcupdate.h>
27#include <linux/percpu-refcount.h>
28#include <linux/scatterlist.h>
29#include <linux/blkzoned.h>
30
31struct module;
32struct scsi_ioctl_command;
33
34struct request_queue;
35struct elevator_queue;
36struct blk_trace;
37struct request;
38struct sg_io_hdr;
39struct bsg_job;
40struct blkcg_gq;
41struct blk_flush_queue;
42struct pr_ops;
43struct rq_qos;
44struct blk_queue_stats;
45struct blk_stat_callback;
46
47#define BLKDEV_MIN_RQ 4
48#define BLKDEV_MAX_RQ 128 /* Default maximum */
49
50/* Must be consistent with blk_mq_poll_stats_bkt() */
51#define BLK_MQ_POLL_STATS_BKTS 16
52
53/*
54 * Maximum number of blkcg policies allowed to be registered concurrently.
55 * Defined here to simplify include dependency.
56 */
57#define BLKCG_MAX_POLS 5
58
59typedef void (rq_end_io_fn)(struct request *, blk_status_t);
60
61#define BLK_RL_SYNCFULL (1U << 0)
62#define BLK_RL_ASYNCFULL (1U << 1)
63
64struct request_list {
65 struct request_queue *q; /* the queue this rl belongs to */
66#ifdef CONFIG_BLK_CGROUP
67 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
68#endif
69 /*
70 * count[], starved[], and wait[] are indexed by
71 * BLK_RW_SYNC/BLK_RW_ASYNC
72 */
73 int count[2];
74 int starved[2];
75 mempool_t *rq_pool;
76 wait_queue_head_t wait[2];
77 unsigned int flags;
78};
79
80/*
81 * request flags */
82typedef __u32 __bitwise req_flags_t;
83
84/* elevator knows about this request */
85#define RQF_SORTED ((__force req_flags_t)(1 << 0))
86/* drive already may have started this one */
87#define RQF_STARTED ((__force req_flags_t)(1 << 1))
88/* uses tagged queueing */
89#define RQF_QUEUED ((__force req_flags_t)(1 << 2))
90/* may not be passed by ioscheduler */
91#define RQF_SOFTBARRIER ((__force req_flags_t)(1 << 3))
92/* request for flush sequence */
93#define RQF_FLUSH_SEQ ((__force req_flags_t)(1 << 4))
94/* merge of different types, fail separately */
95#define RQF_MIXED_MERGE ((__force req_flags_t)(1 << 5))
96/* track inflight for MQ */
97#define RQF_MQ_INFLIGHT ((__force req_flags_t)(1 << 6))
98/* don't call prep for this one */
99#define RQF_DONTPREP ((__force req_flags_t)(1 << 7))
100/* set for "ide_preempt" requests and also for requests for which the SCSI
101 "quiesce" state must be ignored. */
102#define RQF_PREEMPT ((__force req_flags_t)(1 << 8))
103/* contains copies of user pages */
104#define RQF_COPY_USER ((__force req_flags_t)(1 << 9))
105/* vaguely specified driver internal error. Ignored by the block layer */
106#define RQF_FAILED ((__force req_flags_t)(1 << 10))
107/* don't warn about errors */
108#define RQF_QUIET ((__force req_flags_t)(1 << 11))
109/* elevator private data attached */
110#define RQF_ELVPRIV ((__force req_flags_t)(1 << 12))
111/* account I/O stat */
112#define RQF_IO_STAT ((__force req_flags_t)(1 << 13))
113/* request came from our alloc pool */
114#define RQF_ALLOCED ((__force req_flags_t)(1 << 14))
115/* runtime pm request */
116#define RQF_PM ((__force req_flags_t)(1 << 15))
117/* on IO scheduler merge hash */
118#define RQF_HASHED ((__force req_flags_t)(1 << 16))
119/* IO stats tracking on */
120#define RQF_STATS ((__force req_flags_t)(1 << 17))
121/* Look at ->special_vec for the actual data payload instead of the
122 bio chain. */
123#define RQF_SPECIAL_PAYLOAD ((__force req_flags_t)(1 << 18))
124/* The per-zone write lock is held for this request */
125#define RQF_ZONE_WRITE_LOCKED ((__force req_flags_t)(1 << 19))
126/* already slept for hybrid poll */
127#define RQF_MQ_POLL_SLEPT ((__force req_flags_t)(1 << 20))
128/* ->timeout has been called, don't expire again */
129#define RQF_TIMED_OUT ((__force req_flags_t)(1 << 21))
130
131/* flags that prevent us from merging requests: */
132#define RQF_NOMERGE_FLAGS \
133 (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD)
134
135/*
136 * Request state for blk-mq.
137 */
138enum mq_rq_state {
139 MQ_RQ_IDLE = 0,
140 MQ_RQ_IN_FLIGHT = 1,
141 MQ_RQ_COMPLETE = 2,
142};
143
144/*
145 * Try to put the fields that are referenced together in the same cacheline.
146 *
147 * If you modify this structure, make sure to update blk_rq_init() and
148 * especially blk_mq_rq_ctx_init() to take care of the added fields.
149 */
150struct request {
151 struct request_queue *q;
152 struct blk_mq_ctx *mq_ctx;
153
154 int cpu;
155 unsigned int cmd_flags; /* op and common flags */
156 req_flags_t rq_flags;
157
158 int internal_tag;
159
160 /* the following two fields are internal, NEVER access directly */
161 unsigned int __data_len; /* total data len */
162 int tag;
163 sector_t __sector; /* sector cursor */
164
165 struct bio *bio;
166 struct bio *biotail;
167
168 struct list_head queuelist;
169
170 /*
171 * The hash is used inside the scheduler, and killed once the
172 * request reaches the dispatch list. The ipi_list is only used
173 * to queue the request for softirq completion, which is long
174 * after the request has been unhashed (and even removed from
175 * the dispatch list).
176 */
177 union {
178 struct hlist_node hash; /* merge hash */
179 struct list_head ipi_list;
180 };
181
182 /*
183 * The rb_node is only used inside the io scheduler, requests
184 * are pruned when moved to the dispatch queue. So let the
185 * completion_data share space with the rb_node.
186 */
187 union {
188 struct rb_node rb_node; /* sort/lookup */
189 struct bio_vec special_vec;
190 void *completion_data;
191 int error_count; /* for legacy drivers, don't use */
192 };
193
194 /*
195 * Three pointers are available for the IO schedulers, if they need
196 * more they have to dynamically allocate it. Flush requests are
197 * never put on the IO scheduler. So let the flush fields share
198 * space with the elevator data.
199 */
200 union {
201 struct {
202 struct io_cq *icq;
203 void *priv[2];
204 } elv;
205
206 struct {
207 unsigned int seq;
208 struct list_head list;
209 rq_end_io_fn *saved_end_io;
210 } flush;
211 };
212
213 struct gendisk *rq_disk;
214 struct hd_struct *part;
215 /* Time that I/O was submitted to the kernel. */
216 u64 start_time_ns;
217 /* Time that I/O was submitted to the device. */
218 u64 io_start_time_ns;
219
220#ifdef CONFIG_BLK_WBT
221 unsigned short wbt_flags;
222#endif
223#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
224 unsigned short throtl_size;
225#endif
226
227 /*
228 * Number of scatter-gather DMA addr+len pairs after
229 * physical address coalescing is performed.
230 */
231 unsigned short nr_phys_segments;
232
233#if defined(CONFIG_BLK_DEV_INTEGRITY)
234 unsigned short nr_integrity_segments;
235#endif
236
237 unsigned short write_hint;
238 unsigned short ioprio;
239
240 void *special; /* opaque pointer available for LLD use */
241
242 unsigned int extra_len; /* length of alignment and padding */
243
244 enum mq_rq_state state;
245 refcount_t ref;
246
247 unsigned int timeout;
248
249 /* access through blk_rq_set_deadline, blk_rq_deadline */
250 unsigned long __deadline;
251
252 struct list_head timeout_list;
253
254 union {
255 struct __call_single_data csd;
256 u64 fifo_time;
257 };
258
259 /*
260 * completion callback.
261 */
262 rq_end_io_fn *end_io;
263 void *end_io_data;
264
265 /* for bidi */
266 struct request *next_rq;
267
268#ifdef CONFIG_BLK_CGROUP
269 struct request_list *rl; /* rl this rq is alloced from */
270#endif
271};
272
273static inline bool blk_op_is_scsi(unsigned int op)
274{
275 return op == REQ_OP_SCSI_IN || op == REQ_OP_SCSI_OUT;
276}
277
278static inline bool blk_op_is_private(unsigned int op)
279{
280 return op == REQ_OP_DRV_IN || op == REQ_OP_DRV_OUT;
281}
282
283static inline bool blk_rq_is_scsi(struct request *rq)
284{
285 return blk_op_is_scsi(req_op(rq));
286}
287
288static inline bool blk_rq_is_private(struct request *rq)
289{
290 return blk_op_is_private(req_op(rq));
291}
292
293static inline bool blk_rq_is_passthrough(struct request *rq)
294{
295 return blk_rq_is_scsi(rq) || blk_rq_is_private(rq);
296}
297
298static inline bool bio_is_passthrough(struct bio *bio)
299{
300 unsigned op = bio_op(bio);
301
302 return blk_op_is_scsi(op) || blk_op_is_private(op);
303}
304
305static inline unsigned short req_get_ioprio(struct request *req)
306{
307 return req->ioprio;
308}
309
310#include <linux/elevator.h>
311
312struct blk_queue_ctx;
313
314typedef void (request_fn_proc) (struct request_queue *q);
315typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
316typedef bool (poll_q_fn) (struct request_queue *q, blk_qc_t);
317typedef int (prep_rq_fn) (struct request_queue *, struct request *);
318typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
319
320struct bio_vec;
321typedef void (softirq_done_fn)(struct request *);
322typedef int (dma_drain_needed_fn)(struct request *);
323typedef int (lld_busy_fn) (struct request_queue *q);
324typedef int (bsg_job_fn) (struct bsg_job *);
325typedef int (init_rq_fn)(struct request_queue *, struct request *, gfp_t);
326typedef void (exit_rq_fn)(struct request_queue *, struct request *);
327
328enum blk_eh_timer_return {
329 BLK_EH_DONE, /* drivers has completed the command */
330 BLK_EH_RESET_TIMER, /* reset timer and try again */
331};
332
333typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
334
335enum blk_queue_state {
336 Queue_down,
337 Queue_up,
338};
339
340struct blk_queue_tag {
341 struct request **tag_index; /* map of busy tags */
342 unsigned long *tag_map; /* bit map of free/busy tags */
343 int max_depth; /* what we will send to device */
344 int real_max_depth; /* what the array can hold */
345 atomic_t refcnt; /* map can be shared */
346 int alloc_policy; /* tag allocation policy */
347 int next_tag; /* next tag */
348};
349#define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
350#define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
351
352#define BLK_SCSI_MAX_CMDS (256)
353#define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
354
355/*
356 * Zoned block device models (zoned limit).
357 */
358enum blk_zoned_model {
359 BLK_ZONED_NONE, /* Regular block device */
360 BLK_ZONED_HA, /* Host-aware zoned block device */
361 BLK_ZONED_HM, /* Host-managed zoned block device */
362};
363
364struct queue_limits {
365 unsigned long bounce_pfn;
366 unsigned long seg_boundary_mask;
367 unsigned long virt_boundary_mask;
368
369 unsigned int max_hw_sectors;
370 unsigned int max_dev_sectors;
371 unsigned int chunk_sectors;
372 unsigned int max_sectors;
373 unsigned int max_segment_size;
374 unsigned int physical_block_size;
375 unsigned int alignment_offset;
376 unsigned int io_min;
377 unsigned int io_opt;
378 unsigned int max_discard_sectors;
379 unsigned int max_hw_discard_sectors;
380 unsigned int max_write_same_sectors;
381 unsigned int max_write_zeroes_sectors;
382 unsigned int discard_granularity;
383 unsigned int discard_alignment;
384
385 unsigned short logical_block_size;
386 unsigned short max_segments;
387 unsigned short max_integrity_segments;
388 unsigned short max_discard_segments;
389
390 unsigned char misaligned;
391 unsigned char discard_misaligned;
392 unsigned char cluster;
393 unsigned char raid_partial_stripes_expensive;
394 enum blk_zoned_model zoned;
395};
396
397#ifdef CONFIG_BLK_DEV_ZONED
398
399struct blk_zone_report_hdr {
400 unsigned int nr_zones;
401 u8 padding[60];
402};
403
404extern int blkdev_report_zones(struct block_device *bdev,
405 sector_t sector, struct blk_zone *zones,
406 unsigned int *nr_zones, gfp_t gfp_mask);
407extern int blkdev_reset_zones(struct block_device *bdev, sector_t sectors,
408 sector_t nr_sectors, gfp_t gfp_mask);
409
410extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
411 unsigned int cmd, unsigned long arg);
412extern int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode,
413 unsigned int cmd, unsigned long arg);
414
415#else /* CONFIG_BLK_DEV_ZONED */
416
417static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
418 fmode_t mode, unsigned int cmd,
419 unsigned long arg)
420{
421 return -ENOTTY;
422}
423
424static inline int blkdev_reset_zones_ioctl(struct block_device *bdev,
425 fmode_t mode, unsigned int cmd,
426 unsigned long arg)
427{
428 return -ENOTTY;
429}
430
431#endif /* CONFIG_BLK_DEV_ZONED */
432
433struct request_queue {
434 /*
435 * Together with queue_head for cacheline sharing
436 */
437 struct list_head queue_head;
438 struct request *last_merge;
439 struct elevator_queue *elevator;
440 int nr_rqs[2]; /* # allocated [a]sync rqs */
441 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
442
443 struct blk_queue_stats *stats;
444 struct rq_qos *rq_qos;
445
446 /*
447 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
448 * is used, root blkg allocates from @q->root_rl and all other
449 * blkgs from their own blkg->rl. Which one to use should be
450 * determined using bio_request_list().
451 */
452 struct request_list root_rl;
453
454 request_fn_proc *request_fn;
455 make_request_fn *make_request_fn;
456 poll_q_fn *poll_fn;
457 prep_rq_fn *prep_rq_fn;
458 unprep_rq_fn *unprep_rq_fn;
459 softirq_done_fn *softirq_done_fn;
460 rq_timed_out_fn *rq_timed_out_fn;
461 dma_drain_needed_fn *dma_drain_needed;
462 lld_busy_fn *lld_busy_fn;
463 /* Called just after a request is allocated */
464 init_rq_fn *init_rq_fn;
465 /* Called just before a request is freed */
466 exit_rq_fn *exit_rq_fn;
467 /* Called from inside blk_get_request() */
468 void (*initialize_rq_fn)(struct request *rq);
469
470 const struct blk_mq_ops *mq_ops;
471
472 unsigned int *mq_map;
473
474 /* sw queues */
475 struct blk_mq_ctx __percpu *queue_ctx;
476 unsigned int nr_queues;
477
478 unsigned int queue_depth;
479
480 /* hw dispatch queues */
481 struct blk_mq_hw_ctx **queue_hw_ctx;
482 unsigned int nr_hw_queues;
483
484 /*
485 * Dispatch queue sorting
486 */
487 sector_t end_sector;
488 struct request *boundary_rq;
489
490 /*
491 * Delayed queue handling
492 */
493 struct delayed_work delay_work;
494
495 struct backing_dev_info *backing_dev_info;
496
497 /*
498 * The queue owner gets to use this for whatever they like.
499 * ll_rw_blk doesn't touch it.
500 */
501 void *queuedata;
502
503 /*
504 * various queue flags, see QUEUE_* below
505 */
506 unsigned long queue_flags;
507
508 /*
509 * ida allocated id for this queue. Used to index queues from
510 * ioctx.
511 */
512 int id;
513
514 /*
515 * queue needs bounce pages for pages above this limit
516 */
517 gfp_t bounce_gfp;
518
519 /*
520 * protects queue structures from reentrancy. ->__queue_lock should
521 * _never_ be used directly, it is queue private. always use
522 * ->queue_lock.
523 */
524 spinlock_t __queue_lock;
525 spinlock_t *queue_lock;
526
527 /*
528 * queue kobject
529 */
530 struct kobject kobj;
531
532 /*
533 * mq queue kobject
534 */
535 struct kobject mq_kobj;
536
537#ifdef CONFIG_BLK_DEV_INTEGRITY
538 struct blk_integrity integrity;
539#endif /* CONFIG_BLK_DEV_INTEGRITY */
540
541#ifdef CONFIG_PM
542 struct device *dev;
543 int rpm_status;
544 unsigned int nr_pending;
545#endif
546
547 /*
548 * queue settings
549 */
550 unsigned long nr_requests; /* Max # of requests */
551 unsigned int nr_congestion_on;
552 unsigned int nr_congestion_off;
553 unsigned int nr_batching;
554
555 unsigned int dma_drain_size;
556 void *dma_drain_buffer;
557 unsigned int dma_pad_mask;
558 unsigned int dma_alignment;
559
560 struct blk_queue_tag *queue_tags;
561
562 unsigned int nr_sorted;
563 unsigned int in_flight[2];
564
565 /*
566 * Number of active block driver functions for which blk_drain_queue()
567 * must wait. Must be incremented around functions that unlock the
568 * queue_lock internally, e.g. scsi_request_fn().
569 */
570 unsigned int request_fn_active;
571
572 unsigned int rq_timeout;
573 int poll_nsec;
574
575 struct blk_stat_callback *poll_cb;
576 struct blk_rq_stat poll_stat[BLK_MQ_POLL_STATS_BKTS];
577
578 struct timer_list timeout;
579 struct work_struct timeout_work;
580 struct list_head timeout_list;
581
582 struct list_head icq_list;
583#ifdef CONFIG_BLK_CGROUP
584 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
585 struct blkcg_gq *root_blkg;
586 struct list_head blkg_list;
587#endif
588
589 struct queue_limits limits;
590
591#ifdef CONFIG_BLK_DEV_ZONED
592 /*
593 * Zoned block device information for request dispatch control.
594 * nr_zones is the total number of zones of the device. This is always
595 * 0 for regular block devices. seq_zones_bitmap is a bitmap of nr_zones
596 * bits which indicates if a zone is conventional (bit clear) or
597 * sequential (bit set). seq_zones_wlock is a bitmap of nr_zones
598 * bits which indicates if a zone is write locked, that is, if a write
599 * request targeting the zone was dispatched. All three fields are
600 * initialized by the low level device driver (e.g. scsi/sd.c).
601 * Stacking drivers (device mappers) may or may not initialize
602 * these fields.
603 *
604 * Reads of this information must be protected with blk_queue_enter() /
605 * blk_queue_exit(). Modifying this information is only allowed while
606 * no requests are being processed. See also blk_mq_freeze_queue() and
607 * blk_mq_unfreeze_queue().
608 */
609 unsigned int nr_zones;
610 unsigned long *seq_zones_bitmap;
611 unsigned long *seq_zones_wlock;
612#endif /* CONFIG_BLK_DEV_ZONED */
613
614 /*
615 * sg stuff
616 */
617 unsigned int sg_timeout;
618 unsigned int sg_reserved_size;
619 int node;
620#ifdef CONFIG_BLK_DEV_IO_TRACE
621 struct blk_trace *blk_trace;
622 struct mutex blk_trace_mutex;
623#endif
624 /*
625 * for flush operations
626 */
627 struct blk_flush_queue *fq;
628
629 struct list_head requeue_list;
630 spinlock_t requeue_lock;
631 struct delayed_work requeue_work;
632
633 struct mutex sysfs_lock;
634
635 int bypass_depth;
636 atomic_t mq_freeze_depth;
637
638#if defined(CONFIG_BLK_DEV_BSG)
639 bsg_job_fn *bsg_job_fn;
640 struct bsg_class_device bsg_dev;
641#endif
642
643#ifdef CONFIG_BLK_DEV_THROTTLING
644 /* Throttle data */
645 struct throtl_data *td;
646#endif
647 struct rcu_head rcu_head;
648 wait_queue_head_t mq_freeze_wq;
649 struct percpu_ref q_usage_counter;
650 struct list_head all_q_node;
651
652 struct blk_mq_tag_set *tag_set;
653 struct list_head tag_set_list;
654 struct bio_set bio_split;
655
656#ifdef CONFIG_BLK_DEBUG_FS
657 struct dentry *debugfs_dir;
658 struct dentry *sched_debugfs_dir;
659#endif
660
661 bool mq_sysfs_init_done;
662
663 size_t cmd_size;
664 void *rq_alloc_data;
665
666 struct work_struct release_work;
667
668#define BLK_MAX_WRITE_HINTS 5
669 u64 write_hints[BLK_MAX_WRITE_HINTS];
670};
671
672#define QUEUE_FLAG_QUEUED 0 /* uses generic tag queueing */
673#define QUEUE_FLAG_STOPPED 1 /* queue is stopped */
674#define QUEUE_FLAG_DYING 2 /* queue being torn down */
675#define QUEUE_FLAG_BYPASS 3 /* act as dumb FIFO queue */
676#define QUEUE_FLAG_BIDI 4 /* queue supports bidi requests */
677#define QUEUE_FLAG_NOMERGES 5 /* disable merge attempts */
678#define QUEUE_FLAG_SAME_COMP 6 /* complete on same CPU-group */
679#define QUEUE_FLAG_FAIL_IO 7 /* fake timeout */
680#define QUEUE_FLAG_NONROT 9 /* non-rotational device (SSD) */
681#define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
682#define QUEUE_FLAG_IO_STAT 10 /* do IO stats */
683#define QUEUE_FLAG_DISCARD 11 /* supports DISCARD */
684#define QUEUE_FLAG_NOXMERGES 12 /* No extended merges */
685#define QUEUE_FLAG_ADD_RANDOM 13 /* Contributes to random pool */
686#define QUEUE_FLAG_SECERASE 14 /* supports secure erase */
687#define QUEUE_FLAG_SAME_FORCE 15 /* force complete on same CPU */
688#define QUEUE_FLAG_DEAD 16 /* queue tear-down finished */
689#define QUEUE_FLAG_INIT_DONE 17 /* queue is initialized */
690#define QUEUE_FLAG_NO_SG_MERGE 18 /* don't attempt to merge SG segments*/
691#define QUEUE_FLAG_POLL 19 /* IO polling enabled if set */
692#define QUEUE_FLAG_WC 20 /* Write back caching */
693#define QUEUE_FLAG_FUA 21 /* device supports FUA writes */
694#define QUEUE_FLAG_FLUSH_NQ 22 /* flush not queueuable */
695#define QUEUE_FLAG_DAX 23 /* device supports DAX */
696#define QUEUE_FLAG_STATS 24 /* track rq completion times */
697#define QUEUE_FLAG_POLL_STATS 25 /* collecting stats for hybrid polling */
698#define QUEUE_FLAG_REGISTERED 26 /* queue has been registered to a disk */
699#define QUEUE_FLAG_SCSI_PASSTHROUGH 27 /* queue supports SCSI commands */
700#define QUEUE_FLAG_QUIESCED 28 /* queue has been quiesced */
701#define QUEUE_FLAG_PREEMPT_ONLY 29 /* only process REQ_PREEMPT requests */
702
703#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
704 (1 << QUEUE_FLAG_SAME_COMP) | \
705 (1 << QUEUE_FLAG_ADD_RANDOM))
706
707#define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
708 (1 << QUEUE_FLAG_SAME_COMP) | \
709 (1 << QUEUE_FLAG_POLL))
710
711void blk_queue_flag_set(unsigned int flag, struct request_queue *q);
712void blk_queue_flag_clear(unsigned int flag, struct request_queue *q);
713bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);
714bool blk_queue_flag_test_and_clear(unsigned int flag, struct request_queue *q);
715
716#define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
717#define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
718#define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
719#define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
720#define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
721#define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
722#define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
723#define blk_queue_noxmerges(q) \
724 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
725#define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
726#define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
727#define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
728#define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
729#define blk_queue_secure_erase(q) \
730 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags))
731#define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags)
732#define blk_queue_scsi_passthrough(q) \
733 test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags)
734
735#define blk_noretry_request(rq) \
736 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
737 REQ_FAILFAST_DRIVER))
738#define blk_queue_quiesced(q) test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags)
739#define blk_queue_preempt_only(q) \
740 test_bit(QUEUE_FLAG_PREEMPT_ONLY, &(q)->queue_flags)
741#define blk_queue_fua(q) test_bit(QUEUE_FLAG_FUA, &(q)->queue_flags)
742
743extern int blk_set_preempt_only(struct request_queue *q);
744extern void blk_clear_preempt_only(struct request_queue *q);
745
746static inline int queue_in_flight(struct request_queue *q)
747{
748 return q->in_flight[0] + q->in_flight[1];
749}
750
751static inline bool blk_account_rq(struct request *rq)
752{
753 return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq);
754}
755
756#define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
757#define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
758/* rq->queuelist of dequeued request must be list_empty() */
759#define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
760
761#define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
762
763#define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ)
764
765/*
766 * Driver can handle struct request, if it either has an old style
767 * request_fn defined, or is blk-mq based.
768 */
769static inline bool queue_is_rq_based(struct request_queue *q)
770{
771 return q->request_fn || q->mq_ops;
772}
773
774static inline unsigned int blk_queue_cluster(struct request_queue *q)
775{
776 return q->limits.cluster;
777}
778
779static inline enum blk_zoned_model
780blk_queue_zoned_model(struct request_queue *q)
781{
782 return q->limits.zoned;
783}
784
785static inline bool blk_queue_is_zoned(struct request_queue *q)
786{
787 switch (blk_queue_zoned_model(q)) {
788 case BLK_ZONED_HA:
789 case BLK_ZONED_HM:
790 return true;
791 default:
792 return false;
793 }
794}
795
796static inline unsigned int blk_queue_zone_sectors(struct request_queue *q)
797{
798 return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0;
799}
800
801#ifdef CONFIG_BLK_DEV_ZONED
802static inline unsigned int blk_queue_zone_no(struct request_queue *q,
803 sector_t sector)
804{
805 if (!blk_queue_is_zoned(q))
806 return 0;
807 return sector >> ilog2(q->limits.chunk_sectors);
808}
809
810static inline bool blk_queue_zone_is_seq(struct request_queue *q,
811 sector_t sector)
812{
813 if (!blk_queue_is_zoned(q) || !q->seq_zones_bitmap)
814 return false;
815 return test_bit(blk_queue_zone_no(q, sector), q->seq_zones_bitmap);
816}
817#endif /* CONFIG_BLK_DEV_ZONED */
818
819static inline bool rq_is_sync(struct request *rq)
820{
821 return op_is_sync(rq->cmd_flags);
822}
823
824static inline bool blk_rl_full(struct request_list *rl, bool sync)
825{
826 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
827
828 return rl->flags & flag;
829}
830
831static inline void blk_set_rl_full(struct request_list *rl, bool sync)
832{
833 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
834
835 rl->flags |= flag;
836}
837
838static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
839{
840 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
841
842 rl->flags &= ~flag;
843}
844
845static inline bool rq_mergeable(struct request *rq)
846{
847 if (blk_rq_is_passthrough(rq))
848 return false;
849
850 if (req_op(rq) == REQ_OP_FLUSH)
851 return false;
852
853 if (req_op(rq) == REQ_OP_WRITE_ZEROES)
854 return false;
855
856 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
857 return false;
858 if (rq->rq_flags & RQF_NOMERGE_FLAGS)
859 return false;
860
861 return true;
862}
863
864static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
865{
866 if (bio_page(a) == bio_page(b) &&
867 bio_offset(a) == bio_offset(b))
868 return true;
869
870 return false;
871}
872
873static inline unsigned int blk_queue_depth(struct request_queue *q)
874{
875 if (q->queue_depth)
876 return q->queue_depth;
877
878 return q->nr_requests;
879}
880
881/*
882 * q->prep_rq_fn return values
883 */
884enum {
885 BLKPREP_OK, /* serve it */
886 BLKPREP_KILL, /* fatal error, kill, return -EIO */
887 BLKPREP_DEFER, /* leave on queue */
888 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */
889};
890
891extern unsigned long blk_max_low_pfn, blk_max_pfn;
892
893/*
894 * standard bounce addresses:
895 *
896 * BLK_BOUNCE_HIGH : bounce all highmem pages
897 * BLK_BOUNCE_ANY : don't bounce anything
898 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
899 */
900
901#if BITS_PER_LONG == 32
902#define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
903#else
904#define BLK_BOUNCE_HIGH -1ULL
905#endif
906#define BLK_BOUNCE_ANY (-1ULL)
907#define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
908
909/*
910 * default timeout for SG_IO if none specified
911 */
912#define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
913#define BLK_MIN_SG_TIMEOUT (7 * HZ)
914
915struct rq_map_data {
916 struct page **pages;
917 int page_order;
918 int nr_entries;
919 unsigned long offset;
920 int null_mapped;
921 int from_user;
922};
923
924struct req_iterator {
925 struct bvec_iter iter;
926 struct bio *bio;
927};
928
929/* This should not be used directly - use rq_for_each_segment */
930#define for_each_bio(_bio) \
931 for (; _bio; _bio = _bio->bi_next)
932#define __rq_for_each_bio(_bio, rq) \
933 if ((rq->bio)) \
934 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
935
936#define rq_for_each_segment(bvl, _rq, _iter) \
937 __rq_for_each_bio(_iter.bio, _rq) \
938 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
939
940#define rq_iter_last(bvec, _iter) \
941 (_iter.bio->bi_next == NULL && \
942 bio_iter_last(bvec, _iter.iter))
943
944#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
945# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
946#endif
947#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
948extern void rq_flush_dcache_pages(struct request *rq);
949#else
950static inline void rq_flush_dcache_pages(struct request *rq)
951{
952}
953#endif
954
955extern int blk_register_queue(struct gendisk *disk);
956extern void blk_unregister_queue(struct gendisk *disk);
957extern blk_qc_t generic_make_request(struct bio *bio);
958extern blk_qc_t direct_make_request(struct bio *bio);
959extern void blk_rq_init(struct request_queue *q, struct request *rq);
960extern void blk_init_request_from_bio(struct request *req, struct bio *bio);
961extern void blk_put_request(struct request *);
962extern void __blk_put_request(struct request_queue *, struct request *);
963extern struct request *blk_get_request(struct request_queue *, unsigned int op,
964 blk_mq_req_flags_t flags);
965extern void blk_requeue_request(struct request_queue *, struct request *);
966extern int blk_lld_busy(struct request_queue *q);
967extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
968 struct bio_set *bs, gfp_t gfp_mask,
969 int (*bio_ctr)(struct bio *, struct bio *, void *),
970 void *data);
971extern void blk_rq_unprep_clone(struct request *rq);
972extern blk_status_t blk_insert_cloned_request(struct request_queue *q,
973 struct request *rq);
974extern int blk_rq_append_bio(struct request *rq, struct bio **bio);
975extern void blk_delay_queue(struct request_queue *, unsigned long);
976extern void blk_queue_split(struct request_queue *, struct bio **);
977extern void blk_recount_segments(struct request_queue *, struct bio *);
978extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
979extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
980 unsigned int, void __user *);
981extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
982 unsigned int, void __user *);
983extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
984 struct scsi_ioctl_command __user *);
985
986extern int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags);
987extern void blk_queue_exit(struct request_queue *q);
988extern void blk_start_queue(struct request_queue *q);
989extern void blk_start_queue_async(struct request_queue *q);
990extern void blk_stop_queue(struct request_queue *q);
991extern void blk_sync_queue(struct request_queue *q);
992extern void __blk_stop_queue(struct request_queue *q);
993extern void __blk_run_queue(struct request_queue *q);
994extern void __blk_run_queue_uncond(struct request_queue *q);
995extern void blk_run_queue(struct request_queue *);
996extern void blk_run_queue_async(struct request_queue *q);
997extern int blk_rq_map_user(struct request_queue *, struct request *,
998 struct rq_map_data *, void __user *, unsigned long,
999 gfp_t);
1000extern int blk_rq_unmap_user(struct bio *);
1001extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
1002extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
1003 struct rq_map_data *, const struct iov_iter *,
1004 gfp_t);
1005extern void blk_execute_rq(struct request_queue *, struct gendisk *,
1006 struct request *, int);
1007extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
1008 struct request *, int, rq_end_io_fn *);
1009
1010int blk_status_to_errno(blk_status_t status);
1011blk_status_t errno_to_blk_status(int errno);
1012
1013bool blk_poll(struct request_queue *q, blk_qc_t cookie);
1014
1015static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
1016{
1017 return bdev->bd_disk->queue; /* this is never NULL */
1018}
1019
1020/*
1021 * The basic unit of block I/O is a sector. It is used in a number of contexts
1022 * in Linux (blk, bio, genhd). The size of one sector is 512 = 2**9
1023 * bytes. Variables of type sector_t represent an offset or size that is a
1024 * multiple of 512 bytes. Hence these two constants.
1025 */
1026#ifndef SECTOR_SHIFT
1027#define SECTOR_SHIFT 9
1028#endif
1029#ifndef SECTOR_SIZE
1030#define SECTOR_SIZE (1 << SECTOR_SHIFT)
1031#endif
1032
1033/*
1034 * blk_rq_pos() : the current sector
1035 * blk_rq_bytes() : bytes left in the entire request
1036 * blk_rq_cur_bytes() : bytes left in the current segment
1037 * blk_rq_err_bytes() : bytes left till the next error boundary
1038 * blk_rq_sectors() : sectors left in the entire request
1039 * blk_rq_cur_sectors() : sectors left in the current segment
1040 */
1041static inline sector_t blk_rq_pos(const struct request *rq)
1042{
1043 return rq->__sector;
1044}
1045
1046static inline unsigned int blk_rq_bytes(const struct request *rq)
1047{
1048 return rq->__data_len;
1049}
1050
1051static inline int blk_rq_cur_bytes(const struct request *rq)
1052{
1053 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
1054}
1055
1056extern unsigned int blk_rq_err_bytes(const struct request *rq);
1057
1058static inline unsigned int blk_rq_sectors(const struct request *rq)
1059{
1060 return blk_rq_bytes(rq) >> SECTOR_SHIFT;
1061}
1062
1063static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
1064{
1065 return blk_rq_cur_bytes(rq) >> SECTOR_SHIFT;
1066}
1067
1068#ifdef CONFIG_BLK_DEV_ZONED
1069static inline unsigned int blk_rq_zone_no(struct request *rq)
1070{
1071 return blk_queue_zone_no(rq->q, blk_rq_pos(rq));
1072}
1073
1074static inline unsigned int blk_rq_zone_is_seq(struct request *rq)
1075{
1076 return blk_queue_zone_is_seq(rq->q, blk_rq_pos(rq));
1077}
1078#endif /* CONFIG_BLK_DEV_ZONED */
1079
1080/*
1081 * Some commands like WRITE SAME have a payload or data transfer size which
1082 * is different from the size of the request. Any driver that supports such
1083 * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to
1084 * calculate the data transfer size.
1085 */
1086static inline unsigned int blk_rq_payload_bytes(struct request *rq)
1087{
1088 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1089 return rq->special_vec.bv_len;
1090 return blk_rq_bytes(rq);
1091}
1092
1093static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
1094 int op)
1095{
1096 if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
1097 return min(q->limits.max_discard_sectors,
1098 UINT_MAX >> SECTOR_SHIFT);
1099
1100 if (unlikely(op == REQ_OP_WRITE_SAME))
1101 return q->limits.max_write_same_sectors;
1102
1103 if (unlikely(op == REQ_OP_WRITE_ZEROES))
1104 return q->limits.max_write_zeroes_sectors;
1105
1106 return q->limits.max_sectors;
1107}
1108
1109/*
1110 * Return maximum size of a request at given offset. Only valid for
1111 * file system requests.
1112 */
1113static inline unsigned int blk_max_size_offset(struct request_queue *q,
1114 sector_t offset)
1115{
1116 if (!q->limits.chunk_sectors)
1117 return q->limits.max_sectors;
1118
1119 return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
1120 (offset & (q->limits.chunk_sectors - 1))));
1121}
1122
1123static inline unsigned int blk_rq_get_max_sectors(struct request *rq,
1124 sector_t offset)
1125{
1126 struct request_queue *q = rq->q;
1127
1128 if (blk_rq_is_passthrough(rq))
1129 return q->limits.max_hw_sectors;
1130
1131 if (!q->limits.chunk_sectors ||
1132 req_op(rq) == REQ_OP_DISCARD ||
1133 req_op(rq) == REQ_OP_SECURE_ERASE)
1134 return blk_queue_get_max_sectors(q, req_op(rq));
1135
1136 return min(blk_max_size_offset(q, offset),
1137 blk_queue_get_max_sectors(q, req_op(rq)));
1138}
1139
1140static inline unsigned int blk_rq_count_bios(struct request *rq)
1141{
1142 unsigned int nr_bios = 0;
1143 struct bio *bio;
1144
1145 __rq_for_each_bio(bio, rq)
1146 nr_bios++;
1147
1148 return nr_bios;
1149}
1150
1151/*
1152 * Request issue related functions.
1153 */
1154extern struct request *blk_peek_request(struct request_queue *q);
1155extern void blk_start_request(struct request *rq);
1156extern struct request *blk_fetch_request(struct request_queue *q);
1157
1158void blk_steal_bios(struct bio_list *list, struct request *rq);
1159
1160/*
1161 * Request completion related functions.
1162 *
1163 * blk_update_request() completes given number of bytes and updates
1164 * the request without completing it.
1165 *
1166 * blk_end_request() and friends. __blk_end_request() must be called
1167 * with the request queue spinlock acquired.
1168 *
1169 * Several drivers define their own end_request and call
1170 * blk_end_request() for parts of the original function.
1171 * This prevents code duplication in drivers.
1172 */
1173extern bool blk_update_request(struct request *rq, blk_status_t error,
1174 unsigned int nr_bytes);
1175extern void blk_finish_request(struct request *rq, blk_status_t error);
1176extern bool blk_end_request(struct request *rq, blk_status_t error,
1177 unsigned int nr_bytes);
1178extern void blk_end_request_all(struct request *rq, blk_status_t error);
1179extern bool __blk_end_request(struct request *rq, blk_status_t error,
1180 unsigned int nr_bytes);
1181extern void __blk_end_request_all(struct request *rq, blk_status_t error);
1182extern bool __blk_end_request_cur(struct request *rq, blk_status_t error);
1183
1184extern void blk_complete_request(struct request *);
1185extern void __blk_complete_request(struct request *);
1186extern void blk_abort_request(struct request *);
1187extern void blk_unprep_request(struct request *);
1188
1189/*
1190 * Access functions for manipulating queue properties
1191 */
1192extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
1193 spinlock_t *lock, int node_id);
1194extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
1195extern int blk_init_allocated_queue(struct request_queue *);
1196extern void blk_cleanup_queue(struct request_queue *);
1197extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1198extern void blk_queue_bounce_limit(struct request_queue *, u64);
1199extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1200extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1201extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1202extern void blk_queue_max_discard_segments(struct request_queue *,
1203 unsigned short);
1204extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1205extern void blk_queue_max_discard_sectors(struct request_queue *q,
1206 unsigned int max_discard_sectors);
1207extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1208 unsigned int max_write_same_sectors);
1209extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q,
1210 unsigned int max_write_same_sectors);
1211extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
1212extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1213extern void blk_queue_alignment_offset(struct request_queue *q,
1214 unsigned int alignment);
1215extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1216extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1217extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1218extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1219extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth);
1220extern void blk_set_default_limits(struct queue_limits *lim);
1221extern void blk_set_stacking_limits(struct queue_limits *lim);
1222extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1223 sector_t offset);
1224extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1225 sector_t offset);
1226extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1227 sector_t offset);
1228extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1229extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1230extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1231extern int blk_queue_dma_drain(struct request_queue *q,
1232 dma_drain_needed_fn *dma_drain_needed,
1233 void *buf, unsigned int size);
1234extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1235extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1236extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
1237extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1238extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1239extern void blk_queue_dma_alignment(struct request_queue *, int);
1240extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1241extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1242extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1243extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1244extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1245extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
1246
1247/*
1248 * Number of physical segments as sent to the device.
1249 *
1250 * Normally this is the number of discontiguous data segments sent by the
1251 * submitter. But for data-less command like discard we might have no
1252 * actual data segments submitted, but the driver might have to add it's
1253 * own special payload. In that case we still return 1 here so that this
1254 * special payload will be mapped.
1255 */
1256static inline unsigned short blk_rq_nr_phys_segments(struct request *rq)
1257{
1258 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD)
1259 return 1;
1260 return rq->nr_phys_segments;
1261}
1262
1263/*
1264 * Number of discard segments (or ranges) the driver needs to fill in.
1265 * Each discard bio merged into a request is counted as one segment.
1266 */
1267static inline unsigned short blk_rq_nr_discard_segments(struct request *rq)
1268{
1269 return max_t(unsigned short, rq->nr_phys_segments, 1);
1270}
1271
1272extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1273extern void blk_dump_rq_flags(struct request *, char *);
1274extern long nr_blockdev_pages(void);
1275
1276bool __must_check blk_get_queue(struct request_queue *);
1277struct request_queue *blk_alloc_queue(gfp_t);
1278struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id,
1279 spinlock_t *lock);
1280extern void blk_put_queue(struct request_queue *);
1281extern void blk_set_queue_dying(struct request_queue *);
1282
1283/*
1284 * block layer runtime pm functions
1285 */
1286#ifdef CONFIG_PM
1287extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1288extern int blk_pre_runtime_suspend(struct request_queue *q);
1289extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1290extern void blk_pre_runtime_resume(struct request_queue *q);
1291extern void blk_post_runtime_resume(struct request_queue *q, int err);
1292extern void blk_set_runtime_active(struct request_queue *q);
1293#else
1294static inline void blk_pm_runtime_init(struct request_queue *q,
1295 struct device *dev) {}
1296static inline int blk_pre_runtime_suspend(struct request_queue *q)
1297{
1298 return -ENOSYS;
1299}
1300static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1301static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1302static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1303static inline void blk_set_runtime_active(struct request_queue *q) {}
1304#endif
1305
1306/*
1307 * blk_plug permits building a queue of related requests by holding the I/O
1308 * fragments for a short period. This allows merging of sequential requests
1309 * into single larger request. As the requests are moved from a per-task list to
1310 * the device's request_queue in a batch, this results in improved scalability
1311 * as the lock contention for request_queue lock is reduced.
1312 *
1313 * It is ok not to disable preemption when adding the request to the plug list
1314 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1315 * the plug list when the task sleeps by itself. For details, please see
1316 * schedule() where blk_schedule_flush_plug() is called.
1317 */
1318struct blk_plug {
1319 struct list_head list; /* requests */
1320 struct list_head mq_list; /* blk-mq requests */
1321 struct list_head cb_list; /* md requires an unplug callback */
1322};
1323#define BLK_MAX_REQUEST_COUNT 16
1324#define BLK_PLUG_FLUSH_SIZE (128 * 1024)
1325
1326struct blk_plug_cb;
1327typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1328struct blk_plug_cb {
1329 struct list_head list;
1330 blk_plug_cb_fn callback;
1331 void *data;
1332};
1333extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1334 void *data, int size);
1335extern void blk_start_plug(struct blk_plug *);
1336extern void blk_finish_plug(struct blk_plug *);
1337extern void blk_flush_plug_list(struct blk_plug *, bool);
1338
1339static inline void blk_flush_plug(struct task_struct *tsk)
1340{
1341 struct blk_plug *plug = tsk->plug;
1342
1343 if (plug)
1344 blk_flush_plug_list(plug, false);
1345}
1346
1347static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1348{
1349 struct blk_plug *plug = tsk->plug;
1350
1351 if (plug)
1352 blk_flush_plug_list(plug, true);
1353}
1354
1355static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1356{
1357 struct blk_plug *plug = tsk->plug;
1358
1359 return plug &&
1360 (!list_empty(&plug->list) ||
1361 !list_empty(&plug->mq_list) ||
1362 !list_empty(&plug->cb_list));
1363}
1364
1365/*
1366 * tag stuff
1367 */
1368extern int blk_queue_start_tag(struct request_queue *, struct request *);
1369extern struct request *blk_queue_find_tag(struct request_queue *, int);
1370extern void blk_queue_end_tag(struct request_queue *, struct request *);
1371extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
1372extern void blk_queue_free_tags(struct request_queue *);
1373extern int blk_queue_resize_tags(struct request_queue *, int);
1374extern struct blk_queue_tag *blk_init_tags(int, int);
1375extern void blk_free_tags(struct blk_queue_tag *);
1376
1377static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1378 int tag)
1379{
1380 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1381 return NULL;
1382 return bqt->tag_index[tag];
1383}
1384
1385extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1386extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1387 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1388
1389#define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */
1390
1391extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1392 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1393extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1394 sector_t nr_sects, gfp_t gfp_mask, int flags,
1395 struct bio **biop);
1396
1397#define BLKDEV_ZERO_NOUNMAP (1 << 0) /* do not free blocks */
1398#define BLKDEV_ZERO_NOFALLBACK (1 << 1) /* don't write explicit zeroes */
1399
1400extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1401 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop,
1402 unsigned flags);
1403extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1404 sector_t nr_sects, gfp_t gfp_mask, unsigned flags);
1405
1406static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1407 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1408{
1409 return blkdev_issue_discard(sb->s_bdev,
1410 block << (sb->s_blocksize_bits -
1411 SECTOR_SHIFT),
1412 nr_blocks << (sb->s_blocksize_bits -
1413 SECTOR_SHIFT),
1414 gfp_mask, flags);
1415}
1416static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1417 sector_t nr_blocks, gfp_t gfp_mask)
1418{
1419 return blkdev_issue_zeroout(sb->s_bdev,
1420 block << (sb->s_blocksize_bits -
1421 SECTOR_SHIFT),
1422 nr_blocks << (sb->s_blocksize_bits -
1423 SECTOR_SHIFT),
1424 gfp_mask, 0);
1425}
1426
1427extern int blk_verify_command(unsigned char *cmd, fmode_t mode);
1428
1429enum blk_default_limits {
1430 BLK_MAX_SEGMENTS = 128,
1431 BLK_SAFE_MAX_SECTORS = 255,
1432 BLK_DEF_MAX_SECTORS = 2560,
1433 BLK_MAX_SEGMENT_SIZE = 65536,
1434 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1435};
1436
1437static inline unsigned long queue_segment_boundary(struct request_queue *q)
1438{
1439 return q->limits.seg_boundary_mask;
1440}
1441
1442static inline unsigned long queue_virt_boundary(struct request_queue *q)
1443{
1444 return q->limits.virt_boundary_mask;
1445}
1446
1447static inline unsigned int queue_max_sectors(struct request_queue *q)
1448{
1449 return q->limits.max_sectors;
1450}
1451
1452static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1453{
1454 return q->limits.max_hw_sectors;
1455}
1456
1457static inline unsigned short queue_max_segments(struct request_queue *q)
1458{
1459 return q->limits.max_segments;
1460}
1461
1462static inline unsigned short queue_max_discard_segments(struct request_queue *q)
1463{
1464 return q->limits.max_discard_segments;
1465}
1466
1467static inline unsigned int queue_max_segment_size(struct request_queue *q)
1468{
1469 return q->limits.max_segment_size;
1470}
1471
1472static inline unsigned short queue_logical_block_size(struct request_queue *q)
1473{
1474 int retval = 512;
1475
1476 if (q && q->limits.logical_block_size)
1477 retval = q->limits.logical_block_size;
1478
1479 return retval;
1480}
1481
1482static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1483{
1484 return queue_logical_block_size(bdev_get_queue(bdev));
1485}
1486
1487static inline unsigned int queue_physical_block_size(struct request_queue *q)
1488{
1489 return q->limits.physical_block_size;
1490}
1491
1492static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1493{
1494 return queue_physical_block_size(bdev_get_queue(bdev));
1495}
1496
1497static inline unsigned int queue_io_min(struct request_queue *q)
1498{
1499 return q->limits.io_min;
1500}
1501
1502static inline int bdev_io_min(struct block_device *bdev)
1503{
1504 return queue_io_min(bdev_get_queue(bdev));
1505}
1506
1507static inline unsigned int queue_io_opt(struct request_queue *q)
1508{
1509 return q->limits.io_opt;
1510}
1511
1512static inline int bdev_io_opt(struct block_device *bdev)
1513{
1514 return queue_io_opt(bdev_get_queue(bdev));
1515}
1516
1517static inline int queue_alignment_offset(struct request_queue *q)
1518{
1519 if (q->limits.misaligned)
1520 return -1;
1521
1522 return q->limits.alignment_offset;
1523}
1524
1525static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1526{
1527 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1528 unsigned int alignment = sector_div(sector, granularity >> SECTOR_SHIFT)
1529 << SECTOR_SHIFT;
1530
1531 return (granularity + lim->alignment_offset - alignment) % granularity;
1532}
1533
1534static inline int bdev_alignment_offset(struct block_device *bdev)
1535{
1536 struct request_queue *q = bdev_get_queue(bdev);
1537
1538 if (q->limits.misaligned)
1539 return -1;
1540
1541 if (bdev != bdev->bd_contains)
1542 return bdev->bd_part->alignment_offset;
1543
1544 return q->limits.alignment_offset;
1545}
1546
1547static inline int queue_discard_alignment(struct request_queue *q)
1548{
1549 if (q->limits.discard_misaligned)
1550 return -1;
1551
1552 return q->limits.discard_alignment;
1553}
1554
1555static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1556{
1557 unsigned int alignment, granularity, offset;
1558
1559 if (!lim->max_discard_sectors)
1560 return 0;
1561
1562 /* Why are these in bytes, not sectors? */
1563 alignment = lim->discard_alignment >> SECTOR_SHIFT;
1564 granularity = lim->discard_granularity >> SECTOR_SHIFT;
1565 if (!granularity)
1566 return 0;
1567
1568 /* Offset of the partition start in 'granularity' sectors */
1569 offset = sector_div(sector, granularity);
1570
1571 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1572 offset = (granularity + alignment - offset) % granularity;
1573
1574 /* Turn it back into bytes, gaah */
1575 return offset << SECTOR_SHIFT;
1576}
1577
1578static inline int bdev_discard_alignment(struct block_device *bdev)
1579{
1580 struct request_queue *q = bdev_get_queue(bdev);
1581
1582 if (bdev != bdev->bd_contains)
1583 return bdev->bd_part->discard_alignment;
1584
1585 return q->limits.discard_alignment;
1586}
1587
1588static inline unsigned int bdev_write_same(struct block_device *bdev)
1589{
1590 struct request_queue *q = bdev_get_queue(bdev);
1591
1592 if (q)
1593 return q->limits.max_write_same_sectors;
1594
1595 return 0;
1596}
1597
1598static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
1599{
1600 struct request_queue *q = bdev_get_queue(bdev);
1601
1602 if (q)
1603 return q->limits.max_write_zeroes_sectors;
1604
1605 return 0;
1606}
1607
1608static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev)
1609{
1610 struct request_queue *q = bdev_get_queue(bdev);
1611
1612 if (q)
1613 return blk_queue_zoned_model(q);
1614
1615 return BLK_ZONED_NONE;
1616}
1617
1618static inline bool bdev_is_zoned(struct block_device *bdev)
1619{
1620 struct request_queue *q = bdev_get_queue(bdev);
1621
1622 if (q)
1623 return blk_queue_is_zoned(q);
1624
1625 return false;
1626}
1627
1628static inline unsigned int bdev_zone_sectors(struct block_device *bdev)
1629{
1630 struct request_queue *q = bdev_get_queue(bdev);
1631
1632 if (q)
1633 return blk_queue_zone_sectors(q);
1634 return 0;
1635}
1636
1637static inline int queue_dma_alignment(struct request_queue *q)
1638{
1639 return q ? q->dma_alignment : 511;
1640}
1641
1642static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1643 unsigned int len)
1644{
1645 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1646 return !(addr & alignment) && !(len & alignment);
1647}
1648
1649/* assumes size > 256 */
1650static inline unsigned int blksize_bits(unsigned int size)
1651{
1652 unsigned int bits = 8;
1653 do {
1654 bits++;
1655 size >>= 1;
1656 } while (size > 256);
1657 return bits;
1658}
1659
1660static inline unsigned int block_size(struct block_device *bdev)
1661{
1662 return bdev->bd_block_size;
1663}
1664
1665static inline bool queue_flush_queueable(struct request_queue *q)
1666{
1667 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags);
1668}
1669
1670typedef struct {struct page *v;} Sector;
1671
1672unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1673
1674static inline void put_dev_sector(Sector p)
1675{
1676 put_page(p.v);
1677}
1678
1679static inline bool __bvec_gap_to_prev(struct request_queue *q,
1680 struct bio_vec *bprv, unsigned int offset)
1681{
1682 return offset ||
1683 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1684}
1685
1686/*
1687 * Check if adding a bio_vec after bprv with offset would create a gap in
1688 * the SG list. Most drivers don't care about this, but some do.
1689 */
1690static inline bool bvec_gap_to_prev(struct request_queue *q,
1691 struct bio_vec *bprv, unsigned int offset)
1692{
1693 if (!queue_virt_boundary(q))
1694 return false;
1695 return __bvec_gap_to_prev(q, bprv, offset);
1696}
1697
1698/*
1699 * Check if the two bvecs from two bios can be merged to one segment.
1700 * If yes, no need to check gap between the two bios since the 1st bio
1701 * and the 1st bvec in the 2nd bio can be handled in one segment.
1702 */
1703static inline bool bios_segs_mergeable(struct request_queue *q,
1704 struct bio *prev, struct bio_vec *prev_last_bv,
1705 struct bio_vec *next_first_bv)
1706{
1707 if (!BIOVEC_PHYS_MERGEABLE(prev_last_bv, next_first_bv))
1708 return false;
1709 if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv))
1710 return false;
1711 if (prev->bi_seg_back_size + next_first_bv->bv_len >
1712 queue_max_segment_size(q))
1713 return false;
1714 return true;
1715}
1716
1717static inline bool bio_will_gap(struct request_queue *q,
1718 struct request *prev_rq,
1719 struct bio *prev,
1720 struct bio *next)
1721{
1722 if (bio_has_data(prev) && queue_virt_boundary(q)) {
1723 struct bio_vec pb, nb;
1724
1725 /*
1726 * don't merge if the 1st bio starts with non-zero
1727 * offset, otherwise it is quite difficult to respect
1728 * sg gap limit. We work hard to merge a huge number of small
1729 * single bios in case of mkfs.
1730 */
1731 if (prev_rq)
1732 bio_get_first_bvec(prev_rq->bio, &pb);
1733 else
1734 bio_get_first_bvec(prev, &pb);
1735 if (pb.bv_offset)
1736 return true;
1737
1738 /*
1739 * We don't need to worry about the situation that the
1740 * merged segment ends in unaligned virt boundary:
1741 *
1742 * - if 'pb' ends aligned, the merged segment ends aligned
1743 * - if 'pb' ends unaligned, the next bio must include
1744 * one single bvec of 'nb', otherwise the 'nb' can't
1745 * merge with 'pb'
1746 */
1747 bio_get_last_bvec(prev, &pb);
1748 bio_get_first_bvec(next, &nb);
1749
1750 if (!bios_segs_mergeable(q, prev, &pb, &nb))
1751 return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
1752 }
1753
1754 return false;
1755}
1756
1757static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1758{
1759 return bio_will_gap(req->q, req, req->biotail, bio);
1760}
1761
1762static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1763{
1764 return bio_will_gap(req->q, NULL, bio, req->bio);
1765}
1766
1767int kblockd_schedule_work(struct work_struct *work);
1768int kblockd_schedule_work_on(int cpu, struct work_struct *work);
1769int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1770
1771#define MODULE_ALIAS_BLOCKDEV(major,minor) \
1772 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1773#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1774 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1775
1776#if defined(CONFIG_BLK_DEV_INTEGRITY)
1777
1778enum blk_integrity_flags {
1779 BLK_INTEGRITY_VERIFY = 1 << 0,
1780 BLK_INTEGRITY_GENERATE = 1 << 1,
1781 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
1782 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
1783};
1784
1785struct blk_integrity_iter {
1786 void *prot_buf;
1787 void *data_buf;
1788 sector_t seed;
1789 unsigned int data_size;
1790 unsigned short interval;
1791 const char *disk_name;
1792};
1793
1794typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
1795
1796struct blk_integrity_profile {
1797 integrity_processing_fn *generate_fn;
1798 integrity_processing_fn *verify_fn;
1799 const char *name;
1800};
1801
1802extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
1803extern void blk_integrity_unregister(struct gendisk *);
1804extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1805extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1806 struct scatterlist *);
1807extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1808extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1809 struct request *);
1810extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1811 struct bio *);
1812
1813static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1814{
1815 struct blk_integrity *bi = &disk->queue->integrity;
1816
1817 if (!bi->profile)
1818 return NULL;
1819
1820 return bi;
1821}
1822
1823static inline
1824struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1825{
1826 return blk_get_integrity(bdev->bd_disk);
1827}
1828
1829static inline bool blk_integrity_rq(struct request *rq)
1830{
1831 return rq->cmd_flags & REQ_INTEGRITY;
1832}
1833
1834static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1835 unsigned int segs)
1836{
1837 q->limits.max_integrity_segments = segs;
1838}
1839
1840static inline unsigned short
1841queue_max_integrity_segments(struct request_queue *q)
1842{
1843 return q->limits.max_integrity_segments;
1844}
1845
1846static inline bool integrity_req_gap_back_merge(struct request *req,
1847 struct bio *next)
1848{
1849 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1850 struct bio_integrity_payload *bip_next = bio_integrity(next);
1851
1852 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1853 bip_next->bip_vec[0].bv_offset);
1854}
1855
1856static inline bool integrity_req_gap_front_merge(struct request *req,
1857 struct bio *bio)
1858{
1859 struct bio_integrity_payload *bip = bio_integrity(bio);
1860 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1861
1862 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1863 bip_next->bip_vec[0].bv_offset);
1864}
1865
1866/**
1867 * bio_integrity_intervals - Return number of integrity intervals for a bio
1868 * @bi: blk_integrity profile for device
1869 * @sectors: Size of the bio in 512-byte sectors
1870 *
1871 * Description: The block layer calculates everything in 512 byte
1872 * sectors but integrity metadata is done in terms of the data integrity
1873 * interval size of the storage device. Convert the block layer sectors
1874 * to the appropriate number of integrity intervals.
1875 */
1876static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1877 unsigned int sectors)
1878{
1879 return sectors >> (bi->interval_exp - 9);
1880}
1881
1882static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1883 unsigned int sectors)
1884{
1885 return bio_integrity_intervals(bi, sectors) * bi->tuple_size;
1886}
1887
1888#else /* CONFIG_BLK_DEV_INTEGRITY */
1889
1890struct bio;
1891struct block_device;
1892struct gendisk;
1893struct blk_integrity;
1894
1895static inline int blk_integrity_rq(struct request *rq)
1896{
1897 return 0;
1898}
1899static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1900 struct bio *b)
1901{
1902 return 0;
1903}
1904static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1905 struct bio *b,
1906 struct scatterlist *s)
1907{
1908 return 0;
1909}
1910static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1911{
1912 return NULL;
1913}
1914static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1915{
1916 return NULL;
1917}
1918static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1919{
1920 return 0;
1921}
1922static inline void blk_integrity_register(struct gendisk *d,
1923 struct blk_integrity *b)
1924{
1925}
1926static inline void blk_integrity_unregister(struct gendisk *d)
1927{
1928}
1929static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1930 unsigned int segs)
1931{
1932}
1933static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1934{
1935 return 0;
1936}
1937static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1938 struct request *r1,
1939 struct request *r2)
1940{
1941 return true;
1942}
1943static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1944 struct request *r,
1945 struct bio *b)
1946{
1947 return true;
1948}
1949
1950static inline bool integrity_req_gap_back_merge(struct request *req,
1951 struct bio *next)
1952{
1953 return false;
1954}
1955static inline bool integrity_req_gap_front_merge(struct request *req,
1956 struct bio *bio)
1957{
1958 return false;
1959}
1960
1961static inline unsigned int bio_integrity_intervals(struct blk_integrity *bi,
1962 unsigned int sectors)
1963{
1964 return 0;
1965}
1966
1967static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
1968 unsigned int sectors)
1969{
1970 return 0;
1971}
1972
1973#endif /* CONFIG_BLK_DEV_INTEGRITY */
1974
1975struct block_device_operations {
1976 int (*open) (struct block_device *, fmode_t);
1977 void (*release) (struct gendisk *, fmode_t);
1978 int (*rw_page)(struct block_device *, sector_t, struct page *, unsigned int);
1979 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1980 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1981 unsigned int (*check_events) (struct gendisk *disk,
1982 unsigned int clearing);
1983 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1984 int (*media_changed) (struct gendisk *);
1985 void (*unlock_native_capacity) (struct gendisk *);
1986 int (*revalidate_disk) (struct gendisk *);
1987 int (*getgeo)(struct block_device *, struct hd_geometry *);
1988 /* this callback is with swap_lock and sometimes page table lock held */
1989 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1990 struct module *owner;
1991 const struct pr_ops *pr_ops;
1992};
1993
1994extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1995 unsigned long);
1996extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1997extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1998 struct writeback_control *);
1999
2000#ifdef CONFIG_BLK_DEV_ZONED
2001bool blk_req_needs_zone_write_lock(struct request *rq);
2002void __blk_req_zone_write_lock(struct request *rq);
2003void __blk_req_zone_write_unlock(struct request *rq);
2004
2005static inline void blk_req_zone_write_lock(struct request *rq)
2006{
2007 if (blk_req_needs_zone_write_lock(rq))
2008 __blk_req_zone_write_lock(rq);
2009}
2010
2011static inline void blk_req_zone_write_unlock(struct request *rq)
2012{
2013 if (rq->rq_flags & RQF_ZONE_WRITE_LOCKED)
2014 __blk_req_zone_write_unlock(rq);
2015}
2016
2017static inline bool blk_req_zone_is_write_locked(struct request *rq)
2018{
2019 return rq->q->seq_zones_wlock &&
2020 test_bit(blk_rq_zone_no(rq), rq->q->seq_zones_wlock);
2021}
2022
2023static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
2024{
2025 if (!blk_req_needs_zone_write_lock(rq))
2026 return true;
2027 return !blk_req_zone_is_write_locked(rq);
2028}
2029#else
2030static inline bool blk_req_needs_zone_write_lock(struct request *rq)
2031{
2032 return false;
2033}
2034
2035static inline void blk_req_zone_write_lock(struct request *rq)
2036{
2037}
2038
2039static inline void blk_req_zone_write_unlock(struct request *rq)
2040{
2041}
2042static inline bool blk_req_zone_is_write_locked(struct request *rq)
2043{
2044 return false;
2045}
2046
2047static inline bool blk_req_can_dispatch_to_zone(struct request *rq)
2048{
2049 return true;
2050}
2051#endif /* CONFIG_BLK_DEV_ZONED */
2052
2053#else /* CONFIG_BLOCK */
2054
2055struct block_device;
2056
2057/*
2058 * stubs for when the block layer is configured out
2059 */
2060#define buffer_heads_over_limit 0
2061
2062static inline long nr_blockdev_pages(void)
2063{
2064 return 0;
2065}
2066
2067struct blk_plug {
2068};
2069
2070static inline void blk_start_plug(struct blk_plug *plug)
2071{
2072}
2073
2074static inline void blk_finish_plug(struct blk_plug *plug)
2075{
2076}
2077
2078static inline void blk_flush_plug(struct task_struct *task)
2079{
2080}
2081
2082static inline void blk_schedule_flush_plug(struct task_struct *task)
2083{
2084}
2085
2086
2087static inline bool blk_needs_flush_plug(struct task_struct *tsk)
2088{
2089 return false;
2090}
2091
2092static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
2093 sector_t *error_sector)
2094{
2095 return 0;
2096}
2097
2098#endif /* CONFIG_BLOCK */
2099
2100#endif