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/lockdep.h> 8 #include <linux/memblock.h> /* for max_pfn/max_low_pfn */ 9 #include <linux/sched/sysctl.h> 10 #include <linux/timekeeping.h> 11 #include <xen/xen.h> 12 #include "blk-crypto-internal.h" 13 14 struct elv_change_ctx; 15 16 /* 17 * Default upper limit for the software max_sectors limit used for regular I/Os. 18 * This can be increased through sysfs. 19 * 20 * This should not be confused with the max_hw_sector limit that is entirely 21 * controlled by the block device driver, usually based on hardware limits. 22 */ 23 #define BLK_DEF_MAX_SECTORS_CAP (SZ_4M >> SECTOR_SHIFT) 24 25 #define BLK_DEV_MAX_SECTORS (LLONG_MAX >> 9) 26 #define BLK_MIN_SEGMENT_SIZE 4096 27 28 /* Max future timer expiry for timeouts */ 29 #define BLK_MAX_TIMEOUT (5 * HZ) 30 31 extern const struct kobj_type blk_queue_ktype; 32 extern struct dentry *blk_debugfs_root; 33 34 struct blk_flush_queue { 35 spinlock_t mq_flush_lock; 36 unsigned int flush_pending_idx:1; 37 unsigned int flush_running_idx:1; 38 blk_status_t rq_status; 39 unsigned long flush_pending_since; 40 struct list_head flush_queue[2]; 41 unsigned long flush_data_in_flight; 42 struct request *flush_rq; 43 struct rcu_head rcu_head; 44 }; 45 46 bool is_flush_rq(struct request *req); 47 48 struct blk_flush_queue *blk_alloc_flush_queue(int node, int cmd_size, 49 gfp_t flags); 50 void blk_free_flush_queue(struct blk_flush_queue *q); 51 52 bool __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic); 53 bool blk_queue_start_drain(struct request_queue *q); 54 bool __blk_freeze_queue_start(struct request_queue *q, 55 struct task_struct *owner); 56 int __bio_queue_enter(struct request_queue *q, struct bio *bio); 57 void submit_bio_noacct_nocheck(struct bio *bio, bool split); 58 void bio_await_chain(struct bio *bio); 59 60 static inline bool blk_try_enter_queue(struct request_queue *q, bool pm) 61 { 62 rcu_read_lock(); 63 if (!percpu_ref_tryget_live_rcu(&q->q_usage_counter)) 64 goto fail; 65 66 /* 67 * The code that increments the pm_only counter must ensure that the 68 * counter is globally visible before the queue is unfrozen. 69 */ 70 if (blk_queue_pm_only(q) && 71 (!pm || queue_rpm_status(q) == RPM_SUSPENDED)) 72 goto fail_put; 73 74 rcu_read_unlock(); 75 return true; 76 77 fail_put: 78 blk_queue_exit(q); 79 fail: 80 rcu_read_unlock(); 81 return false; 82 } 83 84 static inline int bio_queue_enter(struct bio *bio) 85 { 86 struct request_queue *q = bdev_get_queue(bio->bi_bdev); 87 88 if (blk_try_enter_queue(q, false)) { 89 rwsem_acquire_read(&q->io_lockdep_map, 0, 0, _RET_IP_); 90 rwsem_release(&q->io_lockdep_map, _RET_IP_); 91 return 0; 92 } 93 return __bio_queue_enter(q, bio); 94 } 95 96 static inline void blk_wait_io(struct completion *done) 97 { 98 /* Prevent hang_check timer from firing at us during very long I/O */ 99 unsigned long timeout = sysctl_hung_task_timeout_secs * HZ / 2; 100 101 if (timeout) 102 while (!wait_for_completion_io_timeout(done, timeout)) 103 ; 104 else 105 wait_for_completion_io(done); 106 } 107 108 struct block_device *blkdev_get_no_open(dev_t dev, bool autoload); 109 void blkdev_put_no_open(struct block_device *bdev); 110 111 #define BIO_INLINE_VECS 4 112 struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs, 113 gfp_t gfp_mask); 114 void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs); 115 116 bool bvec_try_merge_hw_page(struct request_queue *q, struct bio_vec *bv, 117 struct page *page, unsigned len, unsigned offset); 118 119 static inline bool biovec_phys_mergeable(struct request_queue *q, 120 struct bio_vec *vec1, struct bio_vec *vec2) 121 { 122 unsigned long mask = queue_segment_boundary(q); 123 phys_addr_t addr1 = bvec_phys(vec1); 124 phys_addr_t addr2 = bvec_phys(vec2); 125 126 /* 127 * Merging adjacent physical pages may not work correctly under KMSAN 128 * if their metadata pages aren't adjacent. Just disable merging. 129 */ 130 if (IS_ENABLED(CONFIG_KMSAN)) 131 return false; 132 133 if (addr1 + vec1->bv_len != addr2) 134 return false; 135 if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page)) 136 return false; 137 if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask)) 138 return false; 139 return true; 140 } 141 142 static inline bool __bvec_gap_to_prev(const struct queue_limits *lim, 143 struct bio_vec *bprv, unsigned int offset) 144 { 145 return (offset & lim->virt_boundary_mask) || 146 ((bprv->bv_offset + bprv->bv_len) & lim->virt_boundary_mask); 147 } 148 149 /* 150 * Check if adding a bio_vec after bprv with offset would create a gap in 151 * the SG list. Most drivers don't care about this, but some do. 152 */ 153 static inline bool bvec_gap_to_prev(const struct queue_limits *lim, 154 struct bio_vec *bprv, unsigned int offset) 155 { 156 if (!lim->virt_boundary_mask) 157 return false; 158 return __bvec_gap_to_prev(lim, bprv, offset); 159 } 160 161 static inline bool rq_mergeable(struct request *rq) 162 { 163 if (blk_rq_is_passthrough(rq)) 164 return false; 165 166 if (req_op(rq) == REQ_OP_FLUSH) 167 return false; 168 169 if (req_op(rq) == REQ_OP_WRITE_ZEROES) 170 return false; 171 172 if (req_op(rq) == REQ_OP_ZONE_APPEND) 173 return false; 174 175 if (rq->cmd_flags & REQ_NOMERGE_FLAGS) 176 return false; 177 if (rq->rq_flags & RQF_NOMERGE_FLAGS) 178 return false; 179 180 return true; 181 } 182 183 /* 184 * There are two different ways to handle DISCARD merges: 185 * 1) If max_discard_segments > 1, the driver treats every bio as a range and 186 * send the bios to controller together. The ranges don't need to be 187 * contiguous. 188 * 2) Otherwise, the request will be normal read/write requests. The ranges 189 * need to be contiguous. 190 */ 191 static inline bool blk_discard_mergable(struct request *req) 192 { 193 if (req_op(req) == REQ_OP_DISCARD && 194 queue_max_discard_segments(req->q) > 1) 195 return true; 196 return false; 197 } 198 199 static inline unsigned int blk_rq_get_max_segments(struct request *rq) 200 { 201 if (req_op(rq) == REQ_OP_DISCARD) 202 return queue_max_discard_segments(rq->q); 203 return queue_max_segments(rq->q); 204 } 205 206 static inline unsigned int blk_queue_get_max_sectors(struct request *rq) 207 { 208 struct request_queue *q = rq->q; 209 enum req_op op = req_op(rq); 210 211 if (unlikely(op == REQ_OP_DISCARD)) 212 return min(q->limits.max_discard_sectors, 213 UINT_MAX >> SECTOR_SHIFT); 214 215 if (unlikely(op == REQ_OP_SECURE_ERASE)) 216 return min(q->limits.max_secure_erase_sectors, 217 UINT_MAX >> SECTOR_SHIFT); 218 219 if (unlikely(op == REQ_OP_WRITE_ZEROES)) 220 return q->limits.max_write_zeroes_sectors; 221 222 if (rq->cmd_flags & REQ_ATOMIC) 223 return q->limits.atomic_write_max_sectors; 224 225 return q->limits.max_sectors; 226 } 227 228 #ifdef CONFIG_BLK_DEV_INTEGRITY 229 void blk_flush_integrity(void); 230 void bio_integrity_free(struct bio *bio); 231 232 /* 233 * Integrity payloads can either be owned by the submitter, in which case 234 * bio_uninit will free them, or owned and generated by the block layer, 235 * in which case we'll verify them here (for reads) and free them before 236 * the bio is handed back to the submitted. 237 */ 238 bool __bio_integrity_endio(struct bio *bio); 239 static inline bool bio_integrity_endio(struct bio *bio) 240 { 241 struct bio_integrity_payload *bip = bio_integrity(bio); 242 243 if (bip && (bip->bip_flags & BIP_BLOCK_INTEGRITY)) 244 return __bio_integrity_endio(bio); 245 return true; 246 } 247 248 bool blk_integrity_merge_rq(struct request_queue *, struct request *, 249 struct request *); 250 bool blk_integrity_merge_bio(struct request_queue *, struct request *, 251 struct bio *); 252 253 static inline bool integrity_req_gap_back_merge(struct request *req, 254 struct bio *next) 255 { 256 struct bio_integrity_payload *bip = bio_integrity(req->bio); 257 struct bio_integrity_payload *bip_next = bio_integrity(next); 258 259 return bvec_gap_to_prev(&req->q->limits, 260 &bip->bip_vec[bip->bip_vcnt - 1], 261 bip_next->bip_vec[0].bv_offset); 262 } 263 264 static inline bool integrity_req_gap_front_merge(struct request *req, 265 struct bio *bio) 266 { 267 struct bio_integrity_payload *bip = bio_integrity(bio); 268 struct bio_integrity_payload *bip_next = bio_integrity(req->bio); 269 270 return bvec_gap_to_prev(&req->q->limits, 271 &bip->bip_vec[bip->bip_vcnt - 1], 272 bip_next->bip_vec[0].bv_offset); 273 } 274 275 extern const struct attribute_group blk_integrity_attr_group; 276 #else /* CONFIG_BLK_DEV_INTEGRITY */ 277 static inline bool blk_integrity_merge_rq(struct request_queue *rq, 278 struct request *r1, struct request *r2) 279 { 280 return true; 281 } 282 static inline bool blk_integrity_merge_bio(struct request_queue *rq, 283 struct request *r, struct bio *b) 284 { 285 return true; 286 } 287 static inline bool integrity_req_gap_back_merge(struct request *req, 288 struct bio *next) 289 { 290 return false; 291 } 292 static inline bool integrity_req_gap_front_merge(struct request *req, 293 struct bio *bio) 294 { 295 return false; 296 } 297 298 static inline void blk_flush_integrity(void) 299 { 300 } 301 static inline bool bio_integrity_endio(struct bio *bio) 302 { 303 return true; 304 } 305 static inline void bio_integrity_free(struct bio *bio) 306 { 307 } 308 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 309 310 unsigned long blk_rq_timeout(unsigned long timeout); 311 void blk_add_timer(struct request *req); 312 313 enum bio_merge_status { 314 BIO_MERGE_OK, 315 BIO_MERGE_NONE, 316 BIO_MERGE_FAILED, 317 }; 318 319 enum bio_merge_status bio_attempt_back_merge(struct request *req, 320 struct bio *bio, unsigned int nr_segs); 321 bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, 322 unsigned int nr_segs); 323 bool blk_bio_list_merge(struct request_queue *q, struct list_head *list, 324 struct bio *bio, unsigned int nr_segs); 325 326 /* 327 * Plug flush limits 328 */ 329 #define BLK_MAX_REQUEST_COUNT 32 330 #define BLK_PLUG_FLUSH_SIZE (128 * 1024) 331 332 /* 333 * Internal elevator interface 334 */ 335 #define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED) 336 337 bool blk_insert_flush(struct request *rq); 338 339 void elv_update_nr_hw_queues(struct request_queue *q, 340 struct elv_change_ctx *ctx); 341 void elevator_set_default(struct request_queue *q); 342 void elevator_set_none(struct request_queue *q); 343 344 ssize_t part_size_show(struct device *dev, struct device_attribute *attr, 345 char *buf); 346 ssize_t part_stat_show(struct device *dev, struct device_attribute *attr, 347 char *buf); 348 ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr, 349 char *buf); 350 ssize_t part_fail_show(struct device *dev, struct device_attribute *attr, 351 char *buf); 352 ssize_t part_fail_store(struct device *dev, struct device_attribute *attr, 353 const char *buf, size_t count); 354 ssize_t part_timeout_show(struct device *, struct device_attribute *, char *); 355 ssize_t part_timeout_store(struct device *, struct device_attribute *, 356 const char *, size_t); 357 358 struct bio *bio_split_discard(struct bio *bio, const struct queue_limits *lim, 359 unsigned *nsegs); 360 struct bio *bio_split_write_zeroes(struct bio *bio, 361 const struct queue_limits *lim, unsigned *nsegs); 362 struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim, 363 unsigned *nr_segs); 364 struct bio *bio_split_zone_append(struct bio *bio, 365 const struct queue_limits *lim, unsigned *nr_segs); 366 367 /* 368 * All drivers must accept single-segments bios that are smaller than PAGE_SIZE. 369 * 370 * This is a quick and dirty check that relies on the fact that bi_io_vec[0] is 371 * always valid if a bio has data. The check might lead to occasional false 372 * positives when bios are cloned, but compared to the performance impact of 373 * cloned bios themselves the loop below doesn't matter anyway. 374 */ 375 static inline bool bio_may_need_split(struct bio *bio, 376 const struct queue_limits *lim) 377 { 378 const struct bio_vec *bv; 379 380 if (lim->chunk_sectors) 381 return true; 382 383 if (!bio->bi_io_vec) 384 return true; 385 386 bv = __bvec_iter_bvec(bio->bi_io_vec, bio->bi_iter); 387 if (bio->bi_iter.bi_size > bv->bv_len - bio->bi_iter.bi_bvec_done) 388 return true; 389 return bv->bv_len + bv->bv_offset > lim->max_fast_segment_size; 390 } 391 392 /** 393 * __bio_split_to_limits - split a bio to fit the queue limits 394 * @bio: bio to be split 395 * @lim: queue limits to split based on 396 * @nr_segs: returns the number of segments in the returned bio 397 * 398 * Check if @bio needs splitting based on the queue limits, and if so split off 399 * a bio fitting the limits from the beginning of @bio and return it. @bio is 400 * shortened to the remainder and re-submitted. 401 * 402 * The split bio is allocated from @q->bio_split, which is provided by the 403 * block layer. 404 */ 405 static inline struct bio *__bio_split_to_limits(struct bio *bio, 406 const struct queue_limits *lim, unsigned int *nr_segs) 407 { 408 switch (bio_op(bio)) { 409 case REQ_OP_READ: 410 case REQ_OP_WRITE: 411 if (bio_may_need_split(bio, lim)) 412 return bio_split_rw(bio, lim, nr_segs); 413 *nr_segs = 1; 414 return bio; 415 case REQ_OP_ZONE_APPEND: 416 return bio_split_zone_append(bio, lim, nr_segs); 417 case REQ_OP_DISCARD: 418 case REQ_OP_SECURE_ERASE: 419 return bio_split_discard(bio, lim, nr_segs); 420 case REQ_OP_WRITE_ZEROES: 421 return bio_split_write_zeroes(bio, lim, nr_segs); 422 default: 423 /* other operations can't be split */ 424 *nr_segs = 0; 425 return bio; 426 } 427 } 428 429 /** 430 * get_max_segment_size() - maximum number of bytes to add as a single segment 431 * @lim: Request queue limits. 432 * @paddr: address of the range to add 433 * @len: maximum length available to add at @paddr 434 * 435 * Returns the maximum number of bytes of the range starting at @paddr that can 436 * be added to a single segment. 437 */ 438 static inline unsigned get_max_segment_size(const struct queue_limits *lim, 439 phys_addr_t paddr, unsigned int len) 440 { 441 /* 442 * Prevent an overflow if mask = ULONG_MAX and offset = 0 by adding 1 443 * after having calculated the minimum. 444 */ 445 return min_t(unsigned long, len, 446 min(lim->seg_boundary_mask - (lim->seg_boundary_mask & paddr), 447 (unsigned long)lim->max_segment_size - 1) + 1); 448 } 449 450 int ll_back_merge_fn(struct request *req, struct bio *bio, 451 unsigned int nr_segs); 452 bool blk_attempt_req_merge(struct request_queue *q, struct request *rq, 453 struct request *next); 454 unsigned int blk_recalc_rq_segments(struct request *rq); 455 bool blk_rq_merge_ok(struct request *rq, struct bio *bio); 456 enum elv_merge blk_try_merge(struct request *rq, struct bio *bio); 457 458 int blk_set_default_limits(struct queue_limits *lim); 459 void blk_apply_bdi_limits(struct backing_dev_info *bdi, 460 struct queue_limits *lim); 461 int blk_dev_init(void); 462 463 void update_io_ticks(struct block_device *part, unsigned long now, bool end); 464 465 static inline void req_set_nomerge(struct request_queue *q, struct request *req) 466 { 467 req->cmd_flags |= REQ_NOMERGE; 468 if (req == q->last_merge) 469 q->last_merge = NULL; 470 } 471 472 /* 473 * Internal io_context interface 474 */ 475 struct io_cq *ioc_find_get_icq(struct request_queue *q); 476 struct io_cq *ioc_lookup_icq(struct request_queue *q); 477 #ifdef CONFIG_BLK_ICQ 478 void ioc_clear_queue(struct request_queue *q); 479 #else 480 static inline void ioc_clear_queue(struct request_queue *q) 481 { 482 } 483 #endif /* CONFIG_BLK_ICQ */ 484 485 #ifdef CONFIG_BLK_DEV_ZONED 486 void disk_init_zone_resources(struct gendisk *disk); 487 void disk_free_zone_resources(struct gendisk *disk); 488 static inline bool bio_zone_write_plugging(struct bio *bio) 489 { 490 return bio_flagged(bio, BIO_ZONE_WRITE_PLUGGING); 491 } 492 static inline bool blk_req_bio_is_zone_append(struct request *rq, 493 struct bio *bio) 494 { 495 return req_op(rq) == REQ_OP_ZONE_APPEND || 496 bio_flagged(bio, BIO_EMULATES_ZONE_APPEND); 497 } 498 void blk_zone_write_plug_bio_merged(struct bio *bio); 499 void blk_zone_write_plug_init_request(struct request *rq); 500 void blk_zone_append_update_request_bio(struct request *rq, struct bio *bio); 501 void blk_zone_mgmt_bio_endio(struct bio *bio); 502 void blk_zone_write_plug_bio_endio(struct bio *bio); 503 static inline void blk_zone_bio_endio(struct bio *bio) 504 { 505 /* 506 * Zone management BIOs may impact zone write plugs (e.g. a zone reset 507 * changes a zone write plug zone write pointer offset), but these 508 * operation do not go through zone write plugging as they may operate 509 * on zones that do not have a zone write 510 * plug. blk_zone_mgmt_bio_endio() handles the potential changes to zone 511 * write plugs that are present. 512 */ 513 if (op_is_zone_mgmt(bio_op(bio))) { 514 blk_zone_mgmt_bio_endio(bio); 515 return; 516 } 517 518 /* 519 * For write BIOs to zoned devices, signal the completion of the BIO so 520 * that the next write BIO can be submitted by zone write plugging. 521 */ 522 if (bio_zone_write_plugging(bio)) 523 blk_zone_write_plug_bio_endio(bio); 524 } 525 526 void blk_zone_write_plug_finish_request(struct request *rq); 527 static inline void blk_zone_finish_request(struct request *rq) 528 { 529 if (rq->rq_flags & RQF_ZONE_WRITE_PLUGGING) 530 blk_zone_write_plug_finish_request(rq); 531 } 532 int blkdev_report_zones_ioctl(struct block_device *bdev, unsigned int cmd, 533 unsigned long arg); 534 int blkdev_zone_mgmt_ioctl(struct block_device *bdev, blk_mode_t mode, 535 unsigned int cmd, unsigned long arg); 536 #else /* CONFIG_BLK_DEV_ZONED */ 537 static inline void disk_init_zone_resources(struct gendisk *disk) 538 { 539 } 540 static inline void disk_free_zone_resources(struct gendisk *disk) 541 { 542 } 543 static inline bool bio_zone_write_plugging(struct bio *bio) 544 { 545 return false; 546 } 547 static inline bool blk_req_bio_is_zone_append(struct request *req, 548 struct bio *bio) 549 { 550 return false; 551 } 552 static inline void blk_zone_write_plug_bio_merged(struct bio *bio) 553 { 554 } 555 static inline void blk_zone_write_plug_init_request(struct request *rq) 556 { 557 } 558 static inline void blk_zone_append_update_request_bio(struct request *rq, 559 struct bio *bio) 560 { 561 } 562 static inline void blk_zone_bio_endio(struct bio *bio) 563 { 564 } 565 static inline void blk_zone_finish_request(struct request *rq) 566 { 567 } 568 static inline int blkdev_report_zones_ioctl(struct block_device *bdev, 569 unsigned int cmd, unsigned long arg) 570 { 571 return -ENOTTY; 572 } 573 static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev, 574 blk_mode_t mode, unsigned int cmd, unsigned long arg) 575 { 576 return -ENOTTY; 577 } 578 #endif /* CONFIG_BLK_DEV_ZONED */ 579 580 struct block_device *bdev_alloc(struct gendisk *disk, u8 partno); 581 void bdev_add(struct block_device *bdev, dev_t dev); 582 void bdev_unhash(struct block_device *bdev); 583 void bdev_drop(struct block_device *bdev); 584 585 int blk_alloc_ext_minor(void); 586 void blk_free_ext_minor(unsigned int minor); 587 #define ADDPART_FLAG_NONE 0 588 #define ADDPART_FLAG_RAID 1 589 #define ADDPART_FLAG_WHOLEDISK 2 590 #define ADDPART_FLAG_READONLY 4 591 int bdev_add_partition(struct gendisk *disk, int partno, sector_t start, 592 sector_t length); 593 int bdev_del_partition(struct gendisk *disk, int partno); 594 int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start, 595 sector_t length); 596 void drop_partition(struct block_device *part); 597 598 void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors); 599 600 struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, 601 struct lock_class_key *lkclass); 602 struct request_queue *blk_alloc_queue(struct queue_limits *lim, int node_id); 603 604 int disk_scan_partitions(struct gendisk *disk, blk_mode_t mode); 605 606 int disk_alloc_events(struct gendisk *disk); 607 void disk_add_events(struct gendisk *disk); 608 void disk_del_events(struct gendisk *disk); 609 void disk_release_events(struct gendisk *disk); 610 void disk_block_events(struct gendisk *disk); 611 void disk_unblock_events(struct gendisk *disk); 612 void disk_flush_events(struct gendisk *disk, unsigned int mask); 613 extern struct device_attribute dev_attr_events; 614 extern struct device_attribute dev_attr_events_async; 615 extern struct device_attribute dev_attr_events_poll_msecs; 616 617 extern struct attribute_group blk_trace_attr_group; 618 619 blk_mode_t file_to_blk_mode(struct file *file); 620 int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode, 621 loff_t lstart, loff_t lend); 622 long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg); 623 int blkdev_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags); 624 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg); 625 626 extern const struct address_space_operations def_blk_aops; 627 628 int disk_register_independent_access_ranges(struct gendisk *disk); 629 void disk_unregister_independent_access_ranges(struct gendisk *disk); 630 631 int should_fail_bio(struct bio *bio); 632 #ifdef CONFIG_FAIL_MAKE_REQUEST 633 bool should_fail_request(struct block_device *part, unsigned int bytes); 634 #else /* CONFIG_FAIL_MAKE_REQUEST */ 635 static inline bool should_fail_request(struct block_device *part, 636 unsigned int bytes) 637 { 638 return false; 639 } 640 #endif /* CONFIG_FAIL_MAKE_REQUEST */ 641 642 /* 643 * Optimized request reference counting. Ideally we'd make timeouts be more 644 * clever, as that's the only reason we need references at all... But until 645 * this happens, this is faster than using refcount_t. Also see: 646 * 647 * abc54d634334 ("io_uring: switch to atomic_t for io_kiocb reference count") 648 */ 649 #define req_ref_zero_or_close_to_overflow(req) \ 650 ((unsigned int) atomic_read(&(req->ref)) + 127u <= 127u) 651 652 static inline bool req_ref_inc_not_zero(struct request *req) 653 { 654 return atomic_inc_not_zero(&req->ref); 655 } 656 657 static inline bool req_ref_put_and_test(struct request *req) 658 { 659 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req)); 660 return atomic_dec_and_test(&req->ref); 661 } 662 663 static inline void req_ref_set(struct request *req, int value) 664 { 665 atomic_set(&req->ref, value); 666 } 667 668 static inline int req_ref_read(struct request *req) 669 { 670 return atomic_read(&req->ref); 671 } 672 673 static inline u64 blk_time_get_ns(void) 674 { 675 struct blk_plug *plug = current->plug; 676 677 if (!plug || !in_task()) 678 return ktime_get_ns(); 679 680 /* 681 * 0 could very well be a valid time, but rather than flag "this is 682 * a valid timestamp" separately, just accept that we'll do an extra 683 * ktime_get_ns() if we just happen to get 0 as the current time. 684 */ 685 if (!plug->cur_ktime) { 686 plug->cur_ktime = ktime_get_ns(); 687 current->flags |= PF_BLOCK_TS; 688 } 689 return plug->cur_ktime; 690 } 691 692 static inline ktime_t blk_time_get(void) 693 { 694 return ns_to_ktime(blk_time_get_ns()); 695 } 696 697 void bdev_release(struct file *bdev_file); 698 int bdev_open(struct block_device *bdev, blk_mode_t mode, void *holder, 699 const struct blk_holder_ops *hops, struct file *bdev_file); 700 int bdev_permission(dev_t dev, blk_mode_t mode, void *holder); 701 702 void blk_integrity_generate(struct bio *bio); 703 void blk_integrity_verify_iter(struct bio *bio, struct bvec_iter *saved_iter); 704 void blk_integrity_prepare(struct request *rq); 705 void blk_integrity_complete(struct request *rq, unsigned int nr_bytes); 706 707 #ifdef CONFIG_LOCKDEP 708 static inline void blk_freeze_acquire_lock(struct request_queue *q) 709 { 710 if (!q->mq_freeze_disk_dead) 711 rwsem_acquire(&q->io_lockdep_map, 0, 1, _RET_IP_); 712 if (!q->mq_freeze_queue_dying) 713 rwsem_acquire(&q->q_lockdep_map, 0, 1, _RET_IP_); 714 } 715 716 static inline void blk_unfreeze_release_lock(struct request_queue *q) 717 { 718 if (!q->mq_freeze_queue_dying) 719 rwsem_release(&q->q_lockdep_map, _RET_IP_); 720 if (!q->mq_freeze_disk_dead) 721 rwsem_release(&q->io_lockdep_map, _RET_IP_); 722 } 723 #else 724 static inline void blk_freeze_acquire_lock(struct request_queue *q) 725 { 726 } 727 static inline void blk_unfreeze_release_lock(struct request_queue *q) 728 { 729 } 730 #endif 731 732 /* 733 * debugfs directory and file creation can trigger fs reclaim, which can enter 734 * back into the block layer request_queue. This can cause deadlock if the 735 * queue is frozen. Use NOIO context together with debugfs_mutex to prevent fs 736 * reclaim from triggering block I/O. 737 */ 738 static inline void blk_debugfs_lock_nomemsave(struct request_queue *q) 739 { 740 mutex_lock(&q->debugfs_mutex); 741 } 742 743 static inline void blk_debugfs_unlock_nomemrestore(struct request_queue *q) 744 { 745 mutex_unlock(&q->debugfs_mutex); 746 } 747 748 static inline unsigned int __must_check blk_debugfs_lock(struct request_queue *q) 749 { 750 unsigned int memflags = memalloc_noio_save(); 751 752 blk_debugfs_lock_nomemsave(q); 753 return memflags; 754 } 755 756 static inline void blk_debugfs_unlock(struct request_queue *q, 757 unsigned int memflags) 758 { 759 blk_debugfs_unlock_nomemrestore(q); 760 memalloc_noio_restore(memflags); 761 } 762 763 #endif /* BLK_INTERNAL_H */ 764