block/blk.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef BLK_INTERNAL_H
   3 #define BLK_INTERNAL_H
   4
   5 #include <linux/bio-integrity.h>
   6 #include <linux/blk-crypto.h>
   7 #include <linux/memblock.h>     /* for max_pfn/max_low_pfn */
   8 #include <linux/sched/sysctl.h>
   9 #include <linux/timekeeping.h>
  10 #include <xen/xen.h>
  11 #include "blk-crypto-internal.h"
  12
  13 struct elevator_type;
  14
  15 /* Max future timer expiry for timeouts */
  16 #define BLK_MAX_TIMEOUT         (5 * HZ)
  17
  18 extern struct dentry *blk_debugfs_root;
  19
  20 struct blk_flush_queue {
  21         spinlock_t              mq_flush_lock;
  22         unsigned int            flush_pending_idx:1;
  23         unsigned int            flush_running_idx:1;
  24         blk_status_t            rq_status;
  25         unsigned long           flush_pending_since;
  26         struct list_head        flush_queue[2];
  27         unsigned long           flush_data_in_flight;
  28         struct request          *flush_rq;
  29 };
  30
  31 bool is_flush_rq(struct request *req);
  32
  33 struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size,
  34                                               gfp_t flags);
  35 void blk_free_flush_queue(struct blk_flush_queue *q);
  36
  37 void blk_freeze_queue(struct request_queue *q);
  38 void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic);
  39 void blk_queue_start_drain(struct request_queue *q);
  40 int __bio_queue_enter(struct request_queue *q, struct bio *bio);
  41 void submit_bio_noacct_nocheck(struct bio *bio);
  42 void bio_await_chain(struct bio *bio);
  43
  44 static inline bool blk_try_enter_queue(struct request_queue *q, bool pm)
  45 {
  46         rcu_read_lock();
  47         if (!percpu_ref_tryget_live_rcu(&q->q_usage_counter))
  48                 goto fail;
  49
  50         /*
  51          * The code that increments the pm_only counter must ensure that the
  52          * counter is globally visible before the queue is unfrozen.
  53          */
  54         if (blk_queue_pm_only(q) &&
  55             (!pm || queue_rpm_status(q) == RPM_SUSPENDED))
  56                 goto fail_put;
  57
  58         rcu_read_unlock();
  59         return true;
  60
  61 fail_put:
  62         blk_queue_exit(q);
  63 fail:
  64         rcu_read_unlock();
  65         return false;
  66 }
  67
  68 static inline int bio_queue_enter(struct bio *bio)
  69 {
  70         struct request_queue *q = bdev_get_queue(bio->bi_bdev);
  71
  72         if (blk_try_enter_queue(q, false))
  73                 return 0;
  74         return __bio_queue_enter(q, bio);
  75 }
  76
  77 static inline void blk_wait_io(struct completion *done)
  78 {
  79         /* Prevent hang_check timer from firing at us during very long I/O */
  80         unsigned long timeout = sysctl_hung_task_timeout_secs * HZ / 2;
  81
  82         if (timeout)
  83                 while (!wait_for_completion_io_timeout(done, timeout))
  84                         ;
  85         else
  86                 wait_for_completion_io(done);
  87 }
  88
  89 #define BIO_INLINE_VECS 4
  90 struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs,
  91                 gfp_t gfp_mask);
  92 void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs);
  93
  94 bool bvec_try_merge_hw_page(struct request_queue *q, struct bio_vec *bv,
  95                 struct page *page, unsigned len, unsigned offset,
  96                 bool *same_page);
  97
  98 static inline bool biovec_phys_mergeable(struct request_queue *q,
  99                 struct bio_vec *vec1, struct bio_vec *vec2)
 100 {
 101         unsigned long mask = queue_segment_boundary(q);
 102         phys_addr_t addr1 = bvec_phys(vec1);
 103         phys_addr_t addr2 = bvec_phys(vec2);
 104
 105         /*
 106          * Merging adjacent physical pages may not work correctly under KMSAN
 107          * if their metadata pages aren't adjacent. Just disable merging.
 108          */
 109         if (IS_ENABLED(CONFIG_KMSAN))
 110                 return false;
 111
 112         if (addr1 + vec1->bv_len != addr2)
 113                 return false;
 114         if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page))
 115                 return false;
 116         if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
 117                 return false;
 118         return true;
 119 }
 120
 121 static inline bool __bvec_gap_to_prev(const struct queue_limits *lim,
 122                 struct bio_vec *bprv, unsigned int offset)
 123 {
 124         return (offset & lim->virt_boundary_mask) ||
 125                 ((bprv->bv_offset + bprv->bv_len) & lim->virt_boundary_mask);
 126 }
 127
 128 /*
 129  * Check if adding a bio_vec after bprv with offset would create a gap in
 130  * the SG list. Most drivers don't care about this, but some do.
 131  */
 132 static inline bool bvec_gap_to_prev(const struct queue_limits *lim,
 133                 struct bio_vec *bprv, unsigned int offset)
 134 {
 135         if (!lim->virt_boundary_mask)
 136                 return false;
 137         return __bvec_gap_to_prev(lim, bprv, offset);
 138 }
 139
 140 static inline bool rq_mergeable(struct request *rq)
 141 {
 142         if (blk_rq_is_passthrough(rq))
 143                 return false;
 144
 145         if (req_op(rq) == REQ_OP_FLUSH)
 146                 return false;
 147
 148         if (req_op(rq) == REQ_OP_WRITE_ZEROES)
 149                 return false;
 150
 151         if (req_op(rq) == REQ_OP_ZONE_APPEND)
 152                 return false;
 153
 154         if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
 155                 return false;
 156         if (rq->rq_flags & RQF_NOMERGE_FLAGS)
 157                 return false;
 158
 159         return true;
 160 }
 161
 162 /*
 163  * There are two different ways to handle DISCARD merges:
 164  *  1) If max_discard_segments > 1, the driver treats every bio as a range and
 165  *     send the bios to controller together. The ranges don't need to be
 166  *     contiguous.
 167  *  2) Otherwise, the request will be normal read/write requests.  The ranges
 168  *     need to be contiguous.
 169  */
 170 static inline bool blk_discard_mergable(struct request *req)
 171 {
 172         if (req_op(req) == REQ_OP_DISCARD &&
 173             queue_max_discard_segments(req->q) > 1)
 174                 return true;
 175         return false;
 176 }
 177
 178 static inline unsigned int blk_rq_get_max_segments(struct request *rq)
 179 {
 180         if (req_op(rq) == REQ_OP_DISCARD)
 181                 return queue_max_discard_segments(rq->q);
 182         return queue_max_segments(rq->q);
 183 }
 184
 185 static inline unsigned int blk_queue_get_max_sectors(struct request *rq)
 186 {
 187         struct request_queue *q = rq->q;
 188         enum req_op op = req_op(rq);
 189
 190         if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE))
 191                 return min(q->limits.max_discard_sectors,
 192                            UINT_MAX >> SECTOR_SHIFT);
 193
 194         if (unlikely(op == REQ_OP_WRITE_ZEROES))
 195                 return q->limits.max_write_zeroes_sectors;
 196
 197         if (rq->cmd_flags & REQ_ATOMIC)
 198                 return q->limits.atomic_write_max_sectors;
 199
 200         return q->limits.max_sectors;
 201 }
 202
 203 #ifdef CONFIG_BLK_DEV_INTEGRITY
 204 void blk_flush_integrity(void);
 205 void bio_integrity_free(struct bio *bio);
 206
 207 /*
 208  * Integrity payloads can either be owned by the submitter, in which case
 209  * bio_uninit will free them, or owned and generated by the block layer,
 210  * in which case we'll verify them here (for reads) and free them before
 211  * the bio is handed back to the submitted.
 212  */
 213 bool __bio_integrity_endio(struct bio *bio);
 214 static inline bool bio_integrity_endio(struct bio *bio)
 215 {
 216         struct bio_integrity_payload *bip = bio_integrity(bio);
 217
 218         if (bip && (bip->bip_flags & BIP_BLOCK_INTEGRITY))
 219                 return __bio_integrity_endio(bio);
 220         return true;
 221 }
 222
 223 bool blk_integrity_merge_rq(struct request_queue *, struct request *,
 224                 struct request *);
 225 bool blk_integrity_merge_bio(struct request_queue *, struct request *,
 226                 struct bio *);
 227
 228 static inline bool integrity_req_gap_back_merge(struct request *req,
 229                 struct bio *next)
 230 {
 231         struct bio_integrity_payload *bip = bio_integrity(req->bio);
 232         struct bio_integrity_payload *bip_next = bio_integrity(next);
 233
 234         return bvec_gap_to_prev(&req->q->limits,
 235                                 &bip->bip_vec[bip->bip_vcnt - 1],
 236                                 bip_next->bip_vec[0].bv_offset);
 237 }
 238
 239 static inline bool integrity_req_gap_front_merge(struct request *req,
 240                 struct bio *bio)
 241 {
 242         struct bio_integrity_payload *bip = bio_integrity(bio);
 243         struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
 244
 245         return bvec_gap_to_prev(&req->q->limits,
 246                                 &bip->bip_vec[bip->bip_vcnt - 1],
 247                                 bip_next->bip_vec[0].bv_offset);
 248 }
 249
 250 extern const struct attribute_group blk_integrity_attr_group;
 251 #else /* CONFIG_BLK_DEV_INTEGRITY */
 252 static inline bool blk_integrity_merge_rq(struct request_queue *rq,
 253                 struct request *r1, struct request *r2)
 254 {
 255         return true;
 256 }
 257 static inline bool blk_integrity_merge_bio(struct request_queue *rq,
 258                 struct request *r, struct bio *b)
 259 {
 260         return true;
 261 }
 262 static inline bool integrity_req_gap_back_merge(struct request *req,
 263                 struct bio *next)
 264 {
 265         return false;
 266 }
 267 static inline bool integrity_req_gap_front_merge(struct request *req,
 268                 struct bio *bio)
 269 {
 270         return false;
 271 }
 272
 273 static inline void blk_flush_integrity(void)
 274 {
 275 }
 276 static inline bool bio_integrity_endio(struct bio *bio)
 277 {
 278         return true;
 279 }
 280 static inline void bio_integrity_free(struct bio *bio)
 281 {
 282 }
 283 #endif /* CONFIG_BLK_DEV_INTEGRITY */
 284
 285 unsigned long blk_rq_timeout(unsigned long timeout);
 286 void blk_add_timer(struct request *req);
 287
 288 enum bio_merge_status {
 289         BIO_MERGE_OK,
 290         BIO_MERGE_NONE,
 291         BIO_MERGE_FAILED,
 292 };
 293
 294 enum bio_merge_status bio_attempt_back_merge(struct request *req,
 295                 struct bio *bio, unsigned int nr_segs);
 296 bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio,
 297                 unsigned int nr_segs);
 298 bool blk_bio_list_merge(struct request_queue *q, struct list_head *list,
 299                         struct bio *bio, unsigned int nr_segs);
 300
 301 /*
 302  * Plug flush limits
 303  */
 304 #define BLK_MAX_REQUEST_COUNT   32
 305 #define BLK_PLUG_FLUSH_SIZE     (128 * 1024)
 306
 307 /*
 308  * Internal elevator interface
 309  */
 310 #define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED)
 311
 312 bool blk_insert_flush(struct request *rq);
 313
 314 int elevator_switch(struct request_queue *q, struct elevator_type *new_e);
 315 void elevator_disable(struct request_queue *q);
 316 void elevator_exit(struct request_queue *q);
 317 int elv_register_queue(struct request_queue *q, bool uevent);
 318 void elv_unregister_queue(struct request_queue *q);
 319
 320 ssize_t part_size_show(struct device *dev, struct device_attribute *attr,
 321                 char *buf);
 322 ssize_t part_stat_show(struct device *dev, struct device_attribute *attr,
 323                 char *buf);
 324 ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
 325                 char *buf);
 326 ssize_t part_fail_show(struct device *dev, struct device_attribute *attr,
 327                 char *buf);
 328 ssize_t part_fail_store(struct device *dev, struct device_attribute *attr,
 329                 const char *buf, size_t count);
 330 ssize_t part_timeout_show(struct device *, struct device_attribute *, char *);
 331 ssize_t part_timeout_store(struct device *, struct device_attribute *,
 332                                 const char *, size_t);
 333
 334 struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim,
 335                 unsigned *nsegs);
 336 struct bio *bio_split_write_zeroes(struct bio *bio,
 337                 const struct queue_limits *lim, unsigned *nsegs);
 338 struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim,
 339                 unsigned *nr_segs);
 340 struct bio *bio_split_zone_append(struct bio *bio,
 341                 const struct queue_limits *lim, unsigned *nr_segs);
 342
 343 /*
 344  * All drivers must accept single-segments bios that are smaller than PAGE_SIZE.
 345  *
 346  * This is a quick and dirty check that relies on the fact that bi_io_vec[0] is
 347  * always valid if a bio has data.  The check might lead to occasional false
 348  * positives when bios are cloned, but compared to the performance impact of
 349  * cloned bios themselves the loop below doesn't matter anyway.
 350  */
 351 static inline bool bio_may_need_split(struct bio *bio,
 352                 const struct queue_limits *lim)
 353 {
 354         return lim->chunk_sectors || bio->bi_vcnt != 1 ||
 355                 bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;
 356 }
 357
 358 /**
 359  * __bio_split_to_limits - split a bio to fit the queue limits
 360  * @bio:     bio to be split
 361  * @lim:     queue limits to split based on
 362  * @nr_segs: returns the number of segments in the returned bio
 363  *
 364  * Check if @bio needs splitting based on the queue limits, and if so split off
 365  * a bio fitting the limits from the beginning of @bio and return it.  @bio is
 366  * shortened to the remainder and re-submitted.
 367  *
 368  * The split bio is allocated from @q->bio_split, which is provided by the
 369  * block layer.
 370  */
 371 static inline struct bio *__bio_split_to_limits(struct bio *bio,
 372                 const struct queue_limits *lim, unsigned int *nr_segs)
 373 {
 374         switch (bio_op(bio)) {
 375         case REQ_OP_READ:
 376         case REQ_OP_WRITE:
 377                 if (bio_may_need_split(bio, lim))
 378                         return bio_split_rw(bio, lim, nr_segs);
 379                 *nr_segs = 1;
 380                 return bio;
 381         case REQ_OP_ZONE_APPEND:
 382                 return bio_split_zone_append(bio, lim, nr_segs);
 383         case REQ_OP_DISCARD:
 384         case REQ_OP_SECURE_ERASE:
 385                 return bio_split_discard(bio, lim, nr_segs);
 386         case REQ_OP_WRITE_ZEROES:
 387                 return bio_split_write_zeroes(bio, lim, nr_segs);
 388         default:
 389                 /* other operations can't be split */
 390                 *nr_segs = 0;
 391                 return bio;
 392         }
 393 }
 394
 395 int ll_back_merge_fn(struct request *req, struct bio *bio,
 396                 unsigned int nr_segs);
 397 bool blk_attempt_req_merge(struct request_queue *q, struct request *rq,
 398                                 struct request *next);
 399 unsigned int blk_recalc_rq_segments(struct request *rq);
 400 bool blk_rq_merge_ok(struct request *rq, struct bio *bio);
 401 enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);
 402
 403 int blk_set_default_limits(struct queue_limits *lim);
 404 void blk_apply_bdi_limits(struct backing_dev_info *bdi,
 405                 struct queue_limits *lim);
 406 int blk_dev_init(void);
 407
 408 /*
 409  * Contribute to IO statistics IFF:
 410  *
 411  *      a) it's attached to a gendisk, and
 412  *      b) the queue had IO stats enabled when this request was started
 413  */
 414 static inline bool blk_do_io_stat(struct request *rq)
 415 {
 416         return (rq->rq_flags & RQF_IO_STAT) && !blk_rq_is_passthrough(rq);
 417 }
 418
 419 void update_io_ticks(struct block_device *part, unsigned long now, bool end);
 420 unsigned int part_in_flight(struct block_device *part);
 421
 422 static inline void req_set_nomerge(struct request_queue *q, struct request *req)
 423 {
 424         req->cmd_flags |= REQ_NOMERGE;
 425         if (req == q->last_merge)
 426                 q->last_merge = NULL;
 427 }
 428
 429 /*
 430  * Internal io_context interface
 431  */
 432 struct io_cq *ioc_find_get_icq(struct request_queue *q);
 433 struct io_cq *ioc_lookup_icq(struct request_queue *q);
 434 #ifdef CONFIG_BLK_ICQ
 435 void ioc_clear_queue(struct request_queue *q);
 436 #else
 437 static inline void ioc_clear_queue(struct request_queue *q)
 438 {
 439 }
 440 #endif /* CONFIG_BLK_ICQ */
 441
 442 struct bio *__blk_queue_bounce(struct bio *bio, struct request_queue *q);
 443
 444 static inline bool blk_queue_may_bounce(struct request_queue *q)
 445 {
 446         return IS_ENABLED(CONFIG_BOUNCE) &&
 447                 (q->limits.features & BLK_FEAT_BOUNCE_HIGH) &&
 448                 max_low_pfn >= max_pfn;
 449 }
 450
 451 static inline struct bio *blk_queue_bounce(struct bio *bio,
 452                 struct request_queue *q)
 453 {
 454         if (unlikely(blk_queue_may_bounce(q) && bio_has_data(bio)))
 455                 return __blk_queue_bounce(bio, q);
 456         return bio;
 457 }
 458
 459 #ifdef CONFIG_BLK_DEV_ZONED
 460 void disk_init_zone_resources(struct gendisk *disk);
 461 void disk_free_zone_resources(struct gendisk *disk);
 462 static inline bool bio_zone_write_plugging(struct bio *bio)
 463 {
 464         return bio_flagged(bio, BIO_ZONE_WRITE_PLUGGING);
 465 }
 466 static inline bool bio_is_zone_append(struct bio *bio)
 467 {
 468         return bio_op(bio) == REQ_OP_ZONE_APPEND ||
 469                 bio_flagged(bio, BIO_EMULATES_ZONE_APPEND);
 470 }
 471 void blk_zone_write_plug_bio_merged(struct bio *bio);
 472 void blk_zone_write_plug_init_request(struct request *rq);
 473 static inline void blk_zone_update_request_bio(struct request *rq,
 474                                                struct bio *bio)
 475 {
 476         /*
 477          * For zone append requests, the request sector indicates the location
 478          * at which the BIO data was written. Return this value to the BIO
 479          * issuer through the BIO iter sector.
 480          * For plugged zone writes, which include emulated zone append, we need
 481          * the original BIO sector so that blk_zone_write_plug_bio_endio() can
 482          * lookup the zone write plug.
 483          */
 484         if (req_op(rq) == REQ_OP_ZONE_APPEND || bio_zone_write_plugging(bio))
 485                 bio->bi_iter.bi_sector = rq->__sector;
 486 }
 487 void blk_zone_write_plug_bio_endio(struct bio *bio);
 488 static inline void blk_zone_bio_endio(struct bio *bio)
 489 {
 490         /*
 491          * For write BIOs to zoned devices, signal the completion of the BIO so
 492          * that the next write BIO can be submitted by zone write plugging.
 493          */
 494         if (bio_zone_write_plugging(bio))
 495                 blk_zone_write_plug_bio_endio(bio);
 496 }
 497
 498 void blk_zone_write_plug_finish_request(struct request *rq);
 499 static inline void blk_zone_finish_request(struct request *rq)
 500 {
 501         if (rq->rq_flags & RQF_ZONE_WRITE_PLUGGING)
 502                 blk_zone_write_plug_finish_request(rq);
 503 }
 504 int blkdev_report_zones_ioctl(struct block_device *bdev, unsigned int cmd,
 505                 unsigned long arg);
 506 int blkdev_zone_mgmt_ioctl(struct block_device *bdev, blk_mode_t mode,
 507                 unsigned int cmd, unsigned long arg);
 508 #else /* CONFIG_BLK_DEV_ZONED */
 509 static inline void disk_init_zone_resources(struct gendisk *disk)
 510 {
 511 }
 512 static inline void disk_free_zone_resources(struct gendisk *disk)
 513 {
 514 }
 515 static inline bool bio_zone_write_plugging(struct bio *bio)
 516 {
 517         return false;
 518 }
 519 static inline bool bio_is_zone_append(struct bio *bio)
 520 {
 521         return false;
 522 }
 523 static inline void blk_zone_write_plug_bio_merged(struct bio *bio)
 524 {
 525 }
 526 static inline void blk_zone_write_plug_init_request(struct request *rq)
 527 {
 528 }
 529 static inline void blk_zone_update_request_bio(struct request *rq,
 530                                                struct bio *bio)
 531 {
 532 }
 533 static inline void blk_zone_bio_endio(struct bio *bio)
 534 {
 535 }
 536 static inline void blk_zone_finish_request(struct request *rq)
 537 {
 538 }
 539 static inline int blkdev_report_zones_ioctl(struct block_device *bdev,
 540                 unsigned int cmd, unsigned long arg)
 541 {
 542         return -ENOTTY;
 543 }
 544 static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
 545                 blk_mode_t mode, unsigned int cmd, unsigned long arg)
 546 {
 547         return -ENOTTY;
 548 }
 549 #endif /* CONFIG_BLK_DEV_ZONED */
 550
 551 struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
 552 void bdev_add(struct block_device *bdev, dev_t dev);
 553 void bdev_unhash(struct block_device *bdev);
 554 void bdev_drop(struct block_device *bdev);
 555
 556 int blk_alloc_ext_minor(void);
 557 void blk_free_ext_minor(unsigned int minor);
 558 #define ADDPART_FLAG_NONE       0
 559 #define ADDPART_FLAG_RAID       1
 560 #define ADDPART_FLAG_WHOLEDISK  2
 561 int bdev_add_partition(struct gendisk *disk, int partno, sector_t start,
 562                 sector_t length);
 563 int bdev_del_partition(struct gendisk *disk, int partno);
 564 int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start,
 565                 sector_t length);
 566 void drop_partition(struct block_device *part);
 567
 568 void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors);
 569
 570 struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
 571                 struct lock_class_key *lkclass);
 572
 573 int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 574                 struct page *page, unsigned int len, unsigned int offset,
 575                 unsigned int max_sectors, bool *same_page);
 576
 577 int bio_add_hw_folio(struct request_queue *q, struct bio *bio,
 578                 struct folio *folio, size_t len, size_t offset,
 579                 unsigned int max_sectors, bool *same_page);
 580
 581 /*
 582  * Clean up a page appropriately, where the page may be pinned, may have a
 583  * ref taken on it or neither.
 584  */
 585 static inline void bio_release_page(struct bio *bio, struct page *page)
 586 {
 587         if (bio_flagged(bio, BIO_PAGE_PINNED))
 588                 unpin_user_page(page);
 589 }
 590
 591 struct request_queue *blk_alloc_queue(struct queue_limits *lim, int node_id);
 592
 593 int disk_scan_partitions(struct gendisk *disk, blk_mode_t mode);
 594
 595 int disk_alloc_events(struct gendisk *disk);
 596 void disk_add_events(struct gendisk *disk);
 597 void disk_del_events(struct gendisk *disk);
 598 void disk_release_events(struct gendisk *disk);
 599 void disk_block_events(struct gendisk *disk);
 600 void disk_unblock_events(struct gendisk *disk);
 601 void disk_flush_events(struct gendisk *disk, unsigned int mask);
 602 extern struct device_attribute dev_attr_events;
 603 extern struct device_attribute dev_attr_events_async;
 604 extern struct device_attribute dev_attr_events_poll_msecs;
 605
 606 extern struct attribute_group blk_trace_attr_group;
 607
 608 blk_mode_t file_to_blk_mode(struct file *file);
 609 int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode,
 610                 loff_t lstart, loff_t lend);
 611 long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
 612 int blkdev_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags);
 613 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
 614
 615 extern const struct address_space_operations def_blk_aops;
 616
 617 int disk_register_independent_access_ranges(struct gendisk *disk);
 618 void disk_unregister_independent_access_ranges(struct gendisk *disk);
 619
 620 #ifdef CONFIG_FAIL_MAKE_REQUEST
 621 bool should_fail_request(struct block_device *part, unsigned int bytes);
 622 #else /* CONFIG_FAIL_MAKE_REQUEST */
 623 static inline bool should_fail_request(struct block_device *part,
 624                                         unsigned int bytes)
 625 {
 626         return false;
 627 }
 628 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 629
 630 /*
 631  * Optimized request reference counting. Ideally we'd make timeouts be more
 632  * clever, as that's the only reason we need references at all... But until
 633  * this happens, this is faster than using refcount_t. Also see:
 634  *
 635  * abc54d634334 ("io_uring: switch to atomic_t for io_kiocb reference count")
 636  */
 637 #define req_ref_zero_or_close_to_overflow(req)  \
 638         ((unsigned int) atomic_read(&(req->ref)) + 127u <= 127u)
 639
 640 static inline bool req_ref_inc_not_zero(struct request *req)
 641 {
 642         return atomic_inc_not_zero(&req->ref);
 643 }
 644
 645 static inline bool req_ref_put_and_test(struct request *req)
 646 {
 647         WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
 648         return atomic_dec_and_test(&req->ref);
 649 }
 650
 651 static inline void req_ref_set(struct request *req, int value)
 652 {
 653         atomic_set(&req->ref, value);
 654 }
 655
 656 static inline int req_ref_read(struct request *req)
 657 {
 658         return atomic_read(&req->ref);
 659 }
 660
 661 static inline u64 blk_time_get_ns(void)
 662 {
 663         struct blk_plug *plug = current->plug;
 664
 665         if (!plug || !in_task())
 666                 return ktime_get_ns();
 667
 668         /*
 669          * 0 could very well be a valid time, but rather than flag "this is
 670          * a valid timestamp" separately, just accept that we'll do an extra
 671          * ktime_get_ns() if we just happen to get 0 as the current time.
 672          */
 673         if (!plug->cur_ktime) {
 674                 plug->cur_ktime = ktime_get_ns();
 675                 current->flags |= PF_BLOCK_TS;
 676         }
 677         return plug->cur_ktime;
 678 }
 679
 680 static inline ktime_t blk_time_get(void)
 681 {
 682         return ns_to_ktime(blk_time_get_ns());
 683 }
 684
 685 /*
 686  * From most significant bit:
 687  * 1 bit: reserved for other usage, see below
 688  * 12 bits: original size of bio
 689  * 51 bits: issue time of bio
 690  */
 691 #define BIO_ISSUE_RES_BITS      1
 692 #define BIO_ISSUE_SIZE_BITS     12
 693 #define BIO_ISSUE_RES_SHIFT     (64 - BIO_ISSUE_RES_BITS)
 694 #define BIO_ISSUE_SIZE_SHIFT    (BIO_ISSUE_RES_SHIFT - BIO_ISSUE_SIZE_BITS)
 695 #define BIO_ISSUE_TIME_MASK     ((1ULL << BIO_ISSUE_SIZE_SHIFT) - 1)
 696 #define BIO_ISSUE_SIZE_MASK     \
 697         (((1ULL << BIO_ISSUE_SIZE_BITS) - 1) << BIO_ISSUE_SIZE_SHIFT)
 698 #define BIO_ISSUE_RES_MASK      (~((1ULL << BIO_ISSUE_RES_SHIFT) - 1))
 699
 700 /* Reserved bit for blk-throtl */
 701 #define BIO_ISSUE_THROTL_SKIP_LATENCY (1ULL << 63)
 702
 703 static inline u64 __bio_issue_time(u64 time)
 704 {
 705         return time & BIO_ISSUE_TIME_MASK;
 706 }
 707
 708 static inline u64 bio_issue_time(struct bio_issue *issue)
 709 {
 710         return __bio_issue_time(issue->value);
 711 }
 712
 713 static inline sector_t bio_issue_size(struct bio_issue *issue)
 714 {
 715         return ((issue->value & BIO_ISSUE_SIZE_MASK) >> BIO_ISSUE_SIZE_SHIFT);
 716 }
 717
 718 static inline void bio_issue_init(struct bio_issue *issue,
 719                                        sector_t size)
 720 {
 721         size &= (1ULL << BIO_ISSUE_SIZE_BITS) - 1;
 722         issue->value = ((issue->value & BIO_ISSUE_RES_MASK) |
 723                         (blk_time_get_ns() & BIO_ISSUE_TIME_MASK) |
 724                         ((u64)size << BIO_ISSUE_SIZE_SHIFT));
 725 }
 726
 727 void bdev_release(struct file *bdev_file);
 728 int bdev_open(struct block_device *bdev, blk_mode_t mode, void *holder,
 729               const struct blk_holder_ops *hops, struct file *bdev_file);
 730 int bdev_permission(dev_t dev, blk_mode_t mode, void *holder);
 731
 732 void blk_integrity_generate(struct bio *bio);
 733 void blk_integrity_verify(struct bio *bio);
 734 void blk_integrity_prepare(struct request *rq);
 735 void blk_integrity_complete(struct request *rq, unsigned int nr_bytes);
 736
 737 #endif /* BLK_INTERNAL_H */