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