1 #ifndef _LINUX_BLKDEV_H 2 #define _LINUX_BLKDEV_H 3 4 #include <linux/sched.h> 5 #include <linux/sched/clock.h> 6 7 #ifdef CONFIG_BLOCK 8 9 #include <linux/major.h> 10 #include <linux/genhd.h> 11 #include <linux/list.h> 12 #include <linux/llist.h> 13 #include <linux/timer.h> 14 #include <linux/workqueue.h> 15 #include <linux/pagemap.h> 16 #include <linux/backing-dev-defs.h> 17 #include <linux/wait.h> 18 #include <linux/mempool.h> 19 #include <linux/pfn.h> 20 #include <linux/bio.h> 21 #include <linux/stringify.h> 22 #include <linux/gfp.h> 23 #include <linux/bsg.h> 24 #include <linux/smp.h> 25 #include <linux/rcupdate.h> 26 #include <linux/percpu-refcount.h> 27 #include <linux/scatterlist.h> 28 #include <linux/blkzoned.h> 29 30 struct module; 31 struct scsi_ioctl_command; 32 33 struct request_queue; 34 struct elevator_queue; 35 struct blk_trace; 36 struct request; 37 struct sg_io_hdr; 38 struct bsg_job; 39 struct blkcg_gq; 40 struct blk_flush_queue; 41 struct pr_ops; 42 struct rq_wb; 43 44 #define BLKDEV_MIN_RQ 4 45 #define BLKDEV_MAX_RQ 128 /* Default maximum */ 46 47 /* 48 * Maximum number of blkcg policies allowed to be registered concurrently. 49 * Defined here to simplify include dependency. 50 */ 51 #define BLKCG_MAX_POLS 2 52 53 typedef void (rq_end_io_fn)(struct request *, int); 54 55 #define BLK_RL_SYNCFULL (1U << 0) 56 #define BLK_RL_ASYNCFULL (1U << 1) 57 58 struct request_list { 59 struct request_queue *q; /* the queue this rl belongs to */ 60 #ifdef CONFIG_BLK_CGROUP 61 struct blkcg_gq *blkg; /* blkg this request pool belongs to */ 62 #endif 63 /* 64 * count[], starved[], and wait[] are indexed by 65 * BLK_RW_SYNC/BLK_RW_ASYNC 66 */ 67 int count[2]; 68 int starved[2]; 69 mempool_t *rq_pool; 70 wait_queue_head_t wait[2]; 71 unsigned int flags; 72 }; 73 74 /* 75 * request flags */ 76 typedef __u32 __bitwise req_flags_t; 77 78 /* elevator knows about this request */ 79 #define RQF_SORTED ((__force req_flags_t)(1 << 0)) 80 /* drive already may have started this one */ 81 #define RQF_STARTED ((__force req_flags_t)(1 << 1)) 82 /* uses tagged queueing */ 83 #define RQF_QUEUED ((__force req_flags_t)(1 << 2)) 84 /* may not be passed by ioscheduler */ 85 #define RQF_SOFTBARRIER ((__force req_flags_t)(1 << 3)) 86 /* request for flush sequence */ 87 #define RQF_FLUSH_SEQ ((__force req_flags_t)(1 << 4)) 88 /* merge of different types, fail separately */ 89 #define RQF_MIXED_MERGE ((__force req_flags_t)(1 << 5)) 90 /* track inflight for MQ */ 91 #define RQF_MQ_INFLIGHT ((__force req_flags_t)(1 << 6)) 92 /* don't call prep for this one */ 93 #define RQF_DONTPREP ((__force req_flags_t)(1 << 7)) 94 /* set for "ide_preempt" requests and also for requests for which the SCSI 95 "quiesce" state must be ignored. */ 96 #define RQF_PREEMPT ((__force req_flags_t)(1 << 8)) 97 /* contains copies of user pages */ 98 #define RQF_COPY_USER ((__force req_flags_t)(1 << 9)) 99 /* vaguely specified driver internal error. Ignored by the block layer */ 100 #define RQF_FAILED ((__force req_flags_t)(1 << 10)) 101 /* don't warn about errors */ 102 #define RQF_QUIET ((__force req_flags_t)(1 << 11)) 103 /* elevator private data attached */ 104 #define RQF_ELVPRIV ((__force req_flags_t)(1 << 12)) 105 /* account I/O stat */ 106 #define RQF_IO_STAT ((__force req_flags_t)(1 << 13)) 107 /* request came from our alloc pool */ 108 #define RQF_ALLOCED ((__force req_flags_t)(1 << 14)) 109 /* runtime pm request */ 110 #define RQF_PM ((__force req_flags_t)(1 << 15)) 111 /* on IO scheduler merge hash */ 112 #define RQF_HASHED ((__force req_flags_t)(1 << 16)) 113 /* IO stats tracking on */ 114 #define RQF_STATS ((__force req_flags_t)(1 << 17)) 115 /* Look at ->special_vec for the actual data payload instead of the 116 bio chain. */ 117 #define RQF_SPECIAL_PAYLOAD ((__force req_flags_t)(1 << 18)) 118 119 /* flags that prevent us from merging requests: */ 120 #define RQF_NOMERGE_FLAGS \ 121 (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD) 122 123 /* 124 * Try to put the fields that are referenced together in the same cacheline. 125 * 126 * If you modify this structure, make sure to update blk_rq_init() and 127 * especially blk_mq_rq_ctx_init() to take care of the added fields. 128 */ 129 struct request { 130 struct list_head queuelist; 131 union { 132 struct call_single_data csd; 133 u64 fifo_time; 134 }; 135 136 struct request_queue *q; 137 struct blk_mq_ctx *mq_ctx; 138 139 int cpu; 140 unsigned int cmd_flags; /* op and common flags */ 141 req_flags_t rq_flags; 142 143 int internal_tag; 144 145 unsigned long atomic_flags; 146 147 /* the following two fields are internal, NEVER access directly */ 148 unsigned int __data_len; /* total data len */ 149 int tag; 150 sector_t __sector; /* sector cursor */ 151 152 struct bio *bio; 153 struct bio *biotail; 154 155 /* 156 * The hash is used inside the scheduler, and killed once the 157 * request reaches the dispatch list. The ipi_list is only used 158 * to queue the request for softirq completion, which is long 159 * after the request has been unhashed (and even removed from 160 * the dispatch list). 161 */ 162 union { 163 struct hlist_node hash; /* merge hash */ 164 struct list_head ipi_list; 165 }; 166 167 /* 168 * The rb_node is only used inside the io scheduler, requests 169 * are pruned when moved to the dispatch queue. So let the 170 * completion_data share space with the rb_node. 171 */ 172 union { 173 struct rb_node rb_node; /* sort/lookup */ 174 struct bio_vec special_vec; 175 void *completion_data; 176 }; 177 178 /* 179 * Three pointers are available for the IO schedulers, if they need 180 * more they have to dynamically allocate it. Flush requests are 181 * never put on the IO scheduler. So let the flush fields share 182 * space with the elevator data. 183 */ 184 union { 185 struct { 186 struct io_cq *icq; 187 void *priv[2]; 188 } elv; 189 190 struct { 191 unsigned int seq; 192 struct list_head list; 193 rq_end_io_fn *saved_end_io; 194 } flush; 195 }; 196 197 struct gendisk *rq_disk; 198 struct hd_struct *part; 199 unsigned long start_time; 200 struct blk_issue_stat issue_stat; 201 #ifdef CONFIG_BLK_CGROUP 202 struct request_list *rl; /* rl this rq is alloced from */ 203 unsigned long long start_time_ns; 204 unsigned long long io_start_time_ns; /* when passed to hardware */ 205 #endif 206 /* Number of scatter-gather DMA addr+len pairs after 207 * physical address coalescing is performed. 208 */ 209 unsigned short nr_phys_segments; 210 #if defined(CONFIG_BLK_DEV_INTEGRITY) 211 unsigned short nr_integrity_segments; 212 #endif 213 214 unsigned short ioprio; 215 216 void *special; /* opaque pointer available for LLD use */ 217 218 int errors; 219 220 unsigned int extra_len; /* length of alignment and padding */ 221 222 unsigned long deadline; 223 struct list_head timeout_list; 224 unsigned int timeout; 225 int retries; 226 227 /* 228 * completion callback. 229 */ 230 rq_end_io_fn *end_io; 231 void *end_io_data; 232 233 /* for bidi */ 234 struct request *next_rq; 235 }; 236 237 static inline bool blk_rq_is_scsi(struct request *rq) 238 { 239 return req_op(rq) == REQ_OP_SCSI_IN || req_op(rq) == REQ_OP_SCSI_OUT; 240 } 241 242 static inline bool blk_rq_is_private(struct request *rq) 243 { 244 return req_op(rq) == REQ_OP_DRV_IN || req_op(rq) == REQ_OP_DRV_OUT; 245 } 246 247 static inline bool blk_rq_is_passthrough(struct request *rq) 248 { 249 return blk_rq_is_scsi(rq) || blk_rq_is_private(rq); 250 } 251 252 static inline unsigned short req_get_ioprio(struct request *req) 253 { 254 return req->ioprio; 255 } 256 257 #include <linux/elevator.h> 258 259 struct blk_queue_ctx; 260 261 typedef void (request_fn_proc) (struct request_queue *q); 262 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio); 263 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 264 typedef void (unprep_rq_fn) (struct request_queue *, struct request *); 265 266 struct bio_vec; 267 typedef void (softirq_done_fn)(struct request *); 268 typedef int (dma_drain_needed_fn)(struct request *); 269 typedef int (lld_busy_fn) (struct request_queue *q); 270 typedef int (bsg_job_fn) (struct bsg_job *); 271 typedef int (init_rq_fn)(struct request_queue *, struct request *, gfp_t); 272 typedef void (exit_rq_fn)(struct request_queue *, struct request *); 273 274 enum blk_eh_timer_return { 275 BLK_EH_NOT_HANDLED, 276 BLK_EH_HANDLED, 277 BLK_EH_RESET_TIMER, 278 }; 279 280 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 281 282 enum blk_queue_state { 283 Queue_down, 284 Queue_up, 285 }; 286 287 struct blk_queue_tag { 288 struct request **tag_index; /* map of busy tags */ 289 unsigned long *tag_map; /* bit map of free/busy tags */ 290 int max_depth; /* what we will send to device */ 291 int real_max_depth; /* what the array can hold */ 292 atomic_t refcnt; /* map can be shared */ 293 int alloc_policy; /* tag allocation policy */ 294 int next_tag; /* next tag */ 295 }; 296 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */ 297 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */ 298 299 #define BLK_SCSI_MAX_CMDS (256) 300 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 301 302 /* 303 * Zoned block device models (zoned limit). 304 */ 305 enum blk_zoned_model { 306 BLK_ZONED_NONE, /* Regular block device */ 307 BLK_ZONED_HA, /* Host-aware zoned block device */ 308 BLK_ZONED_HM, /* Host-managed zoned block device */ 309 }; 310 311 struct queue_limits { 312 unsigned long bounce_pfn; 313 unsigned long seg_boundary_mask; 314 unsigned long virt_boundary_mask; 315 316 unsigned int max_hw_sectors; 317 unsigned int max_dev_sectors; 318 unsigned int chunk_sectors; 319 unsigned int max_sectors; 320 unsigned int max_segment_size; 321 unsigned int physical_block_size; 322 unsigned int alignment_offset; 323 unsigned int io_min; 324 unsigned int io_opt; 325 unsigned int max_discard_sectors; 326 unsigned int max_hw_discard_sectors; 327 unsigned int max_write_same_sectors; 328 unsigned int max_write_zeroes_sectors; 329 unsigned int discard_granularity; 330 unsigned int discard_alignment; 331 332 unsigned short logical_block_size; 333 unsigned short max_segments; 334 unsigned short max_integrity_segments; 335 unsigned short max_discard_segments; 336 337 unsigned char misaligned; 338 unsigned char discard_misaligned; 339 unsigned char cluster; 340 unsigned char discard_zeroes_data; 341 unsigned char raid_partial_stripes_expensive; 342 enum blk_zoned_model zoned; 343 }; 344 345 #ifdef CONFIG_BLK_DEV_ZONED 346 347 struct blk_zone_report_hdr { 348 unsigned int nr_zones; 349 u8 padding[60]; 350 }; 351 352 extern int blkdev_report_zones(struct block_device *bdev, 353 sector_t sector, struct blk_zone *zones, 354 unsigned int *nr_zones, gfp_t gfp_mask); 355 extern int blkdev_reset_zones(struct block_device *bdev, sector_t sectors, 356 sector_t nr_sectors, gfp_t gfp_mask); 357 358 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode, 359 unsigned int cmd, unsigned long arg); 360 extern int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode, 361 unsigned int cmd, unsigned long arg); 362 363 #else /* CONFIG_BLK_DEV_ZONED */ 364 365 static inline int blkdev_report_zones_ioctl(struct block_device *bdev, 366 fmode_t mode, unsigned int cmd, 367 unsigned long arg) 368 { 369 return -ENOTTY; 370 } 371 372 static inline int blkdev_reset_zones_ioctl(struct block_device *bdev, 373 fmode_t mode, unsigned int cmd, 374 unsigned long arg) 375 { 376 return -ENOTTY; 377 } 378 379 #endif /* CONFIG_BLK_DEV_ZONED */ 380 381 struct request_queue { 382 /* 383 * Together with queue_head for cacheline sharing 384 */ 385 struct list_head queue_head; 386 struct request *last_merge; 387 struct elevator_queue *elevator; 388 int nr_rqs[2]; /* # allocated [a]sync rqs */ 389 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */ 390 391 struct rq_wb *rq_wb; 392 393 /* 394 * If blkcg is not used, @q->root_rl serves all requests. If blkcg 395 * is used, root blkg allocates from @q->root_rl and all other 396 * blkgs from their own blkg->rl. Which one to use should be 397 * determined using bio_request_list(). 398 */ 399 struct request_list root_rl; 400 401 request_fn_proc *request_fn; 402 make_request_fn *make_request_fn; 403 prep_rq_fn *prep_rq_fn; 404 unprep_rq_fn *unprep_rq_fn; 405 softirq_done_fn *softirq_done_fn; 406 rq_timed_out_fn *rq_timed_out_fn; 407 dma_drain_needed_fn *dma_drain_needed; 408 lld_busy_fn *lld_busy_fn; 409 init_rq_fn *init_rq_fn; 410 exit_rq_fn *exit_rq_fn; 411 412 const struct blk_mq_ops *mq_ops; 413 414 unsigned int *mq_map; 415 416 /* sw queues */ 417 struct blk_mq_ctx __percpu *queue_ctx; 418 unsigned int nr_queues; 419 420 unsigned int queue_depth; 421 422 /* hw dispatch queues */ 423 struct blk_mq_hw_ctx **queue_hw_ctx; 424 unsigned int nr_hw_queues; 425 426 /* 427 * Dispatch queue sorting 428 */ 429 sector_t end_sector; 430 struct request *boundary_rq; 431 432 /* 433 * Delayed queue handling 434 */ 435 struct delayed_work delay_work; 436 437 struct backing_dev_info *backing_dev_info; 438 439 /* 440 * The queue owner gets to use this for whatever they like. 441 * ll_rw_blk doesn't touch it. 442 */ 443 void *queuedata; 444 445 /* 446 * various queue flags, see QUEUE_* below 447 */ 448 unsigned long queue_flags; 449 450 /* 451 * ida allocated id for this queue. Used to index queues from 452 * ioctx. 453 */ 454 int id; 455 456 /* 457 * queue needs bounce pages for pages above this limit 458 */ 459 gfp_t bounce_gfp; 460 461 /* 462 * protects queue structures from reentrancy. ->__queue_lock should 463 * _never_ be used directly, it is queue private. always use 464 * ->queue_lock. 465 */ 466 spinlock_t __queue_lock; 467 spinlock_t *queue_lock; 468 469 /* 470 * queue kobject 471 */ 472 struct kobject kobj; 473 474 /* 475 * mq queue kobject 476 */ 477 struct kobject mq_kobj; 478 479 #ifdef CONFIG_BLK_DEV_INTEGRITY 480 struct blk_integrity integrity; 481 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 482 483 #ifdef CONFIG_PM 484 struct device *dev; 485 int rpm_status; 486 unsigned int nr_pending; 487 #endif 488 489 /* 490 * queue settings 491 */ 492 unsigned long nr_requests; /* Max # of requests */ 493 unsigned int nr_congestion_on; 494 unsigned int nr_congestion_off; 495 unsigned int nr_batching; 496 497 unsigned int dma_drain_size; 498 void *dma_drain_buffer; 499 unsigned int dma_pad_mask; 500 unsigned int dma_alignment; 501 502 struct blk_queue_tag *queue_tags; 503 struct list_head tag_busy_list; 504 505 unsigned int nr_sorted; 506 unsigned int in_flight[2]; 507 508 struct blk_rq_stat rq_stats[2]; 509 510 /* 511 * Number of active block driver functions for which blk_drain_queue() 512 * must wait. Must be incremented around functions that unlock the 513 * queue_lock internally, e.g. scsi_request_fn(). 514 */ 515 unsigned int request_fn_active; 516 517 unsigned int rq_timeout; 518 int poll_nsec; 519 struct timer_list timeout; 520 struct work_struct timeout_work; 521 struct list_head timeout_list; 522 523 struct list_head icq_list; 524 #ifdef CONFIG_BLK_CGROUP 525 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); 526 struct blkcg_gq *root_blkg; 527 struct list_head blkg_list; 528 #endif 529 530 struct queue_limits limits; 531 532 /* 533 * sg stuff 534 */ 535 unsigned int sg_timeout; 536 unsigned int sg_reserved_size; 537 int node; 538 #ifdef CONFIG_BLK_DEV_IO_TRACE 539 struct blk_trace *blk_trace; 540 #endif 541 /* 542 * for flush operations 543 */ 544 struct blk_flush_queue *fq; 545 546 struct list_head requeue_list; 547 spinlock_t requeue_lock; 548 struct delayed_work requeue_work; 549 550 struct mutex sysfs_lock; 551 552 int bypass_depth; 553 atomic_t mq_freeze_depth; 554 555 #if defined(CONFIG_BLK_DEV_BSG) 556 bsg_job_fn *bsg_job_fn; 557 int bsg_job_size; 558 struct bsg_class_device bsg_dev; 559 #endif 560 561 #ifdef CONFIG_BLK_DEV_THROTTLING 562 /* Throttle data */ 563 struct throtl_data *td; 564 #endif 565 struct rcu_head rcu_head; 566 wait_queue_head_t mq_freeze_wq; 567 struct percpu_ref q_usage_counter; 568 struct list_head all_q_node; 569 570 struct blk_mq_tag_set *tag_set; 571 struct list_head tag_set_list; 572 struct bio_set *bio_split; 573 574 #ifdef CONFIG_BLK_DEBUG_FS 575 struct dentry *debugfs_dir; 576 struct dentry *mq_debugfs_dir; 577 #endif 578 579 bool mq_sysfs_init_done; 580 581 size_t cmd_size; 582 void *rq_alloc_data; 583 }; 584 585 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 586 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 587 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 588 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 589 #define QUEUE_FLAG_DYING 5 /* queue being torn down */ 590 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */ 591 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ 592 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ 593 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ 594 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ 595 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ 596 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ 597 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 598 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ 599 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ 600 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ 601 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ 602 #define QUEUE_FLAG_SECERASE 17 /* supports secure erase */ 603 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ 604 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */ 605 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */ 606 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/ 607 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */ 608 #define QUEUE_FLAG_WC 23 /* Write back caching */ 609 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */ 610 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */ 611 #define QUEUE_FLAG_DAX 26 /* device supports DAX */ 612 #define QUEUE_FLAG_STATS 27 /* track rq completion times */ 613 614 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 615 (1 << QUEUE_FLAG_STACKABLE) | \ 616 (1 << QUEUE_FLAG_SAME_COMP) | \ 617 (1 << QUEUE_FLAG_ADD_RANDOM)) 618 619 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 620 (1 << QUEUE_FLAG_STACKABLE) | \ 621 (1 << QUEUE_FLAG_SAME_COMP) | \ 622 (1 << QUEUE_FLAG_POLL)) 623 624 static inline void queue_lockdep_assert_held(struct request_queue *q) 625 { 626 if (q->queue_lock) 627 lockdep_assert_held(q->queue_lock); 628 } 629 630 static inline void queue_flag_set_unlocked(unsigned int flag, 631 struct request_queue *q) 632 { 633 __set_bit(flag, &q->queue_flags); 634 } 635 636 static inline int queue_flag_test_and_clear(unsigned int flag, 637 struct request_queue *q) 638 { 639 queue_lockdep_assert_held(q); 640 641 if (test_bit(flag, &q->queue_flags)) { 642 __clear_bit(flag, &q->queue_flags); 643 return 1; 644 } 645 646 return 0; 647 } 648 649 static inline int queue_flag_test_and_set(unsigned int flag, 650 struct request_queue *q) 651 { 652 queue_lockdep_assert_held(q); 653 654 if (!test_bit(flag, &q->queue_flags)) { 655 __set_bit(flag, &q->queue_flags); 656 return 0; 657 } 658 659 return 1; 660 } 661 662 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 663 { 664 queue_lockdep_assert_held(q); 665 __set_bit(flag, &q->queue_flags); 666 } 667 668 static inline void queue_flag_clear_unlocked(unsigned int flag, 669 struct request_queue *q) 670 { 671 __clear_bit(flag, &q->queue_flags); 672 } 673 674 static inline int queue_in_flight(struct request_queue *q) 675 { 676 return q->in_flight[0] + q->in_flight[1]; 677 } 678 679 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 680 { 681 queue_lockdep_assert_held(q); 682 __clear_bit(flag, &q->queue_flags); 683 } 684 685 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 686 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 687 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags) 688 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 689 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags) 690 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags) 691 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 692 #define blk_queue_noxmerges(q) \ 693 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 694 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 695 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 696 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 697 #define blk_queue_stackable(q) \ 698 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 699 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 700 #define blk_queue_secure_erase(q) \ 701 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags)) 702 #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags) 703 704 #define blk_noretry_request(rq) \ 705 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 706 REQ_FAILFAST_DRIVER)) 707 708 static inline bool blk_account_rq(struct request *rq) 709 { 710 return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq); 711 } 712 713 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 714 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 715 /* rq->queuelist of dequeued request must be list_empty() */ 716 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 717 718 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 719 720 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ) 721 722 /* 723 * Driver can handle struct request, if it either has an old style 724 * request_fn defined, or is blk-mq based. 725 */ 726 static inline bool queue_is_rq_based(struct request_queue *q) 727 { 728 return q->request_fn || q->mq_ops; 729 } 730 731 static inline unsigned int blk_queue_cluster(struct request_queue *q) 732 { 733 return q->limits.cluster; 734 } 735 736 static inline enum blk_zoned_model 737 blk_queue_zoned_model(struct request_queue *q) 738 { 739 return q->limits.zoned; 740 } 741 742 static inline bool blk_queue_is_zoned(struct request_queue *q) 743 { 744 switch (blk_queue_zoned_model(q)) { 745 case BLK_ZONED_HA: 746 case BLK_ZONED_HM: 747 return true; 748 default: 749 return false; 750 } 751 } 752 753 static inline unsigned int blk_queue_zone_sectors(struct request_queue *q) 754 { 755 return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0; 756 } 757 758 static inline bool rq_is_sync(struct request *rq) 759 { 760 return op_is_sync(rq->cmd_flags); 761 } 762 763 static inline bool blk_rl_full(struct request_list *rl, bool sync) 764 { 765 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 766 767 return rl->flags & flag; 768 } 769 770 static inline void blk_set_rl_full(struct request_list *rl, bool sync) 771 { 772 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 773 774 rl->flags |= flag; 775 } 776 777 static inline void blk_clear_rl_full(struct request_list *rl, bool sync) 778 { 779 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 780 781 rl->flags &= ~flag; 782 } 783 784 static inline bool rq_mergeable(struct request *rq) 785 { 786 if (blk_rq_is_passthrough(rq)) 787 return false; 788 789 if (req_op(rq) == REQ_OP_FLUSH) 790 return false; 791 792 if (req_op(rq) == REQ_OP_WRITE_ZEROES) 793 return false; 794 795 if (rq->cmd_flags & REQ_NOMERGE_FLAGS) 796 return false; 797 if (rq->rq_flags & RQF_NOMERGE_FLAGS) 798 return false; 799 800 return true; 801 } 802 803 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b) 804 { 805 if (bio_data(a) == bio_data(b)) 806 return true; 807 808 return false; 809 } 810 811 static inline unsigned int blk_queue_depth(struct request_queue *q) 812 { 813 if (q->queue_depth) 814 return q->queue_depth; 815 816 return q->nr_requests; 817 } 818 819 /* 820 * q->prep_rq_fn return values 821 */ 822 enum { 823 BLKPREP_OK, /* serve it */ 824 BLKPREP_KILL, /* fatal error, kill, return -EIO */ 825 BLKPREP_DEFER, /* leave on queue */ 826 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */ 827 }; 828 829 extern unsigned long blk_max_low_pfn, blk_max_pfn; 830 831 /* 832 * standard bounce addresses: 833 * 834 * BLK_BOUNCE_HIGH : bounce all highmem pages 835 * BLK_BOUNCE_ANY : don't bounce anything 836 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 837 */ 838 839 #if BITS_PER_LONG == 32 840 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 841 #else 842 #define BLK_BOUNCE_HIGH -1ULL 843 #endif 844 #define BLK_BOUNCE_ANY (-1ULL) 845 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 846 847 /* 848 * default timeout for SG_IO if none specified 849 */ 850 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 851 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 852 853 #ifdef CONFIG_BOUNCE 854 extern int init_emergency_isa_pool(void); 855 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 856 #else 857 static inline int init_emergency_isa_pool(void) 858 { 859 return 0; 860 } 861 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 862 { 863 } 864 #endif /* CONFIG_MMU */ 865 866 struct rq_map_data { 867 struct page **pages; 868 int page_order; 869 int nr_entries; 870 unsigned long offset; 871 int null_mapped; 872 int from_user; 873 }; 874 875 struct req_iterator { 876 struct bvec_iter iter; 877 struct bio *bio; 878 }; 879 880 /* This should not be used directly - use rq_for_each_segment */ 881 #define for_each_bio(_bio) \ 882 for (; _bio; _bio = _bio->bi_next) 883 #define __rq_for_each_bio(_bio, rq) \ 884 if ((rq->bio)) \ 885 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 886 887 #define rq_for_each_segment(bvl, _rq, _iter) \ 888 __rq_for_each_bio(_iter.bio, _rq) \ 889 bio_for_each_segment(bvl, _iter.bio, _iter.iter) 890 891 #define rq_iter_last(bvec, _iter) \ 892 (_iter.bio->bi_next == NULL && \ 893 bio_iter_last(bvec, _iter.iter)) 894 895 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 896 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 897 #endif 898 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 899 extern void rq_flush_dcache_pages(struct request *rq); 900 #else 901 static inline void rq_flush_dcache_pages(struct request *rq) 902 { 903 } 904 #endif 905 906 #ifdef CONFIG_PRINTK 907 #define vfs_msg(sb, level, fmt, ...) \ 908 __vfs_msg(sb, level, fmt, ##__VA_ARGS__) 909 #else 910 #define vfs_msg(sb, level, fmt, ...) \ 911 do { \ 912 no_printk(fmt, ##__VA_ARGS__); \ 913 __vfs_msg(sb, "", " "); \ 914 } while (0) 915 #endif 916 917 extern int blk_register_queue(struct gendisk *disk); 918 extern void blk_unregister_queue(struct gendisk *disk); 919 extern blk_qc_t generic_make_request(struct bio *bio); 920 extern void blk_rq_init(struct request_queue *q, struct request *rq); 921 extern void blk_put_request(struct request *); 922 extern void __blk_put_request(struct request_queue *, struct request *); 923 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 924 extern void blk_requeue_request(struct request_queue *, struct request *); 925 extern int blk_lld_busy(struct request_queue *q); 926 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 927 struct bio_set *bs, gfp_t gfp_mask, 928 int (*bio_ctr)(struct bio *, struct bio *, void *), 929 void *data); 930 extern void blk_rq_unprep_clone(struct request *rq); 931 extern int blk_insert_cloned_request(struct request_queue *q, 932 struct request *rq); 933 extern int blk_rq_append_bio(struct request *rq, struct bio *bio); 934 extern void blk_delay_queue(struct request_queue *, unsigned long); 935 extern void blk_queue_split(struct request_queue *, struct bio **, 936 struct bio_set *); 937 extern void blk_recount_segments(struct request_queue *, struct bio *); 938 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 939 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 940 unsigned int, void __user *); 941 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 942 unsigned int, void __user *); 943 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 944 struct scsi_ioctl_command __user *); 945 946 extern int blk_queue_enter(struct request_queue *q, bool nowait); 947 extern void blk_queue_exit(struct request_queue *q); 948 extern void blk_start_queue(struct request_queue *q); 949 extern void blk_start_queue_async(struct request_queue *q); 950 extern void blk_stop_queue(struct request_queue *q); 951 extern void blk_sync_queue(struct request_queue *q); 952 extern void __blk_stop_queue(struct request_queue *q); 953 extern void __blk_run_queue(struct request_queue *q); 954 extern void __blk_run_queue_uncond(struct request_queue *q); 955 extern void blk_run_queue(struct request_queue *); 956 extern void blk_run_queue_async(struct request_queue *q); 957 extern void blk_mq_quiesce_queue(struct request_queue *q); 958 extern int blk_rq_map_user(struct request_queue *, struct request *, 959 struct rq_map_data *, void __user *, unsigned long, 960 gfp_t); 961 extern int blk_rq_unmap_user(struct bio *); 962 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 963 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 964 struct rq_map_data *, const struct iov_iter *, 965 gfp_t); 966 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 967 struct request *, int); 968 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 969 struct request *, int, rq_end_io_fn *); 970 971 bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie); 972 973 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 974 { 975 return bdev->bd_disk->queue; /* this is never NULL */ 976 } 977 978 /* 979 * blk_rq_pos() : the current sector 980 * blk_rq_bytes() : bytes left in the entire request 981 * blk_rq_cur_bytes() : bytes left in the current segment 982 * blk_rq_err_bytes() : bytes left till the next error boundary 983 * blk_rq_sectors() : sectors left in the entire request 984 * blk_rq_cur_sectors() : sectors left in the current segment 985 */ 986 static inline sector_t blk_rq_pos(const struct request *rq) 987 { 988 return rq->__sector; 989 } 990 991 static inline unsigned int blk_rq_bytes(const struct request *rq) 992 { 993 return rq->__data_len; 994 } 995 996 static inline int blk_rq_cur_bytes(const struct request *rq) 997 { 998 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 999 } 1000 1001 extern unsigned int blk_rq_err_bytes(const struct request *rq); 1002 1003 static inline unsigned int blk_rq_sectors(const struct request *rq) 1004 { 1005 return blk_rq_bytes(rq) >> 9; 1006 } 1007 1008 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 1009 { 1010 return blk_rq_cur_bytes(rq) >> 9; 1011 } 1012 1013 /* 1014 * Some commands like WRITE SAME have a payload or data transfer size which 1015 * is different from the size of the request. Any driver that supports such 1016 * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to 1017 * calculate the data transfer size. 1018 */ 1019 static inline unsigned int blk_rq_payload_bytes(struct request *rq) 1020 { 1021 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD) 1022 return rq->special_vec.bv_len; 1023 return blk_rq_bytes(rq); 1024 } 1025 1026 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q, 1027 int op) 1028 { 1029 if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE)) 1030 return min(q->limits.max_discard_sectors, UINT_MAX >> 9); 1031 1032 if (unlikely(op == REQ_OP_WRITE_SAME)) 1033 return q->limits.max_write_same_sectors; 1034 1035 if (unlikely(op == REQ_OP_WRITE_ZEROES)) 1036 return q->limits.max_write_zeroes_sectors; 1037 1038 return q->limits.max_sectors; 1039 } 1040 1041 /* 1042 * Return maximum size of a request at given offset. Only valid for 1043 * file system requests. 1044 */ 1045 static inline unsigned int blk_max_size_offset(struct request_queue *q, 1046 sector_t offset) 1047 { 1048 if (!q->limits.chunk_sectors) 1049 return q->limits.max_sectors; 1050 1051 return q->limits.chunk_sectors - 1052 (offset & (q->limits.chunk_sectors - 1)); 1053 } 1054 1055 static inline unsigned int blk_rq_get_max_sectors(struct request *rq, 1056 sector_t offset) 1057 { 1058 struct request_queue *q = rq->q; 1059 1060 if (blk_rq_is_passthrough(rq)) 1061 return q->limits.max_hw_sectors; 1062 1063 if (!q->limits.chunk_sectors || 1064 req_op(rq) == REQ_OP_DISCARD || 1065 req_op(rq) == REQ_OP_SECURE_ERASE) 1066 return blk_queue_get_max_sectors(q, req_op(rq)); 1067 1068 return min(blk_max_size_offset(q, offset), 1069 blk_queue_get_max_sectors(q, req_op(rq))); 1070 } 1071 1072 static inline unsigned int blk_rq_count_bios(struct request *rq) 1073 { 1074 unsigned int nr_bios = 0; 1075 struct bio *bio; 1076 1077 __rq_for_each_bio(bio, rq) 1078 nr_bios++; 1079 1080 return nr_bios; 1081 } 1082 1083 /* 1084 * blk_rq_set_prio - associate a request with prio from ioc 1085 * @rq: request of interest 1086 * @ioc: target iocontext 1087 * 1088 * Assocate request prio with ioc prio so request based drivers 1089 * can leverage priority information. 1090 */ 1091 static inline void blk_rq_set_prio(struct request *rq, struct io_context *ioc) 1092 { 1093 if (ioc) 1094 rq->ioprio = ioc->ioprio; 1095 } 1096 1097 /* 1098 * Request issue related functions. 1099 */ 1100 extern struct request *blk_peek_request(struct request_queue *q); 1101 extern void blk_start_request(struct request *rq); 1102 extern struct request *blk_fetch_request(struct request_queue *q); 1103 1104 /* 1105 * Request completion related functions. 1106 * 1107 * blk_update_request() completes given number of bytes and updates 1108 * the request without completing it. 1109 * 1110 * blk_end_request() and friends. __blk_end_request() must be called 1111 * with the request queue spinlock acquired. 1112 * 1113 * Several drivers define their own end_request and call 1114 * blk_end_request() for parts of the original function. 1115 * This prevents code duplication in drivers. 1116 */ 1117 extern bool blk_update_request(struct request *rq, int error, 1118 unsigned int nr_bytes); 1119 extern void blk_finish_request(struct request *rq, int error); 1120 extern bool blk_end_request(struct request *rq, int error, 1121 unsigned int nr_bytes); 1122 extern void blk_end_request_all(struct request *rq, int error); 1123 extern bool blk_end_request_cur(struct request *rq, int error); 1124 extern bool blk_end_request_err(struct request *rq, int error); 1125 extern bool __blk_end_request(struct request *rq, int error, 1126 unsigned int nr_bytes); 1127 extern void __blk_end_request_all(struct request *rq, int error); 1128 extern bool __blk_end_request_cur(struct request *rq, int error); 1129 extern bool __blk_end_request_err(struct request *rq, int error); 1130 1131 extern void blk_complete_request(struct request *); 1132 extern void __blk_complete_request(struct request *); 1133 extern void blk_abort_request(struct request *); 1134 extern void blk_unprep_request(struct request *); 1135 1136 /* 1137 * Access functions for manipulating queue properties 1138 */ 1139 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 1140 spinlock_t *lock, int node_id); 1141 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 1142 extern int blk_init_allocated_queue(struct request_queue *); 1143 extern void blk_cleanup_queue(struct request_queue *); 1144 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 1145 extern void blk_queue_bounce_limit(struct request_queue *, u64); 1146 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 1147 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int); 1148 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 1149 extern void blk_queue_max_discard_segments(struct request_queue *, 1150 unsigned short); 1151 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 1152 extern void blk_queue_max_discard_sectors(struct request_queue *q, 1153 unsigned int max_discard_sectors); 1154 extern void blk_queue_max_write_same_sectors(struct request_queue *q, 1155 unsigned int max_write_same_sectors); 1156 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q, 1157 unsigned int max_write_same_sectors); 1158 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 1159 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 1160 extern void blk_queue_alignment_offset(struct request_queue *q, 1161 unsigned int alignment); 1162 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 1163 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 1164 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 1165 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 1166 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth); 1167 extern void blk_set_default_limits(struct queue_limits *lim); 1168 extern void blk_set_stacking_limits(struct queue_limits *lim); 1169 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 1170 sector_t offset); 1171 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 1172 sector_t offset); 1173 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 1174 sector_t offset); 1175 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 1176 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 1177 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 1178 extern int blk_queue_dma_drain(struct request_queue *q, 1179 dma_drain_needed_fn *dma_drain_needed, 1180 void *buf, unsigned int size); 1181 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 1182 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 1183 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long); 1184 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 1185 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 1186 extern void blk_queue_dma_alignment(struct request_queue *, int); 1187 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 1188 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 1189 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 1190 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 1191 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 1192 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua); 1193 1194 /* 1195 * Number of physical segments as sent to the device. 1196 * 1197 * Normally this is the number of discontiguous data segments sent by the 1198 * submitter. But for data-less command like discard we might have no 1199 * actual data segments submitted, but the driver might have to add it's 1200 * own special payload. In that case we still return 1 here so that this 1201 * special payload will be mapped. 1202 */ 1203 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq) 1204 { 1205 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD) 1206 return 1; 1207 return rq->nr_phys_segments; 1208 } 1209 1210 /* 1211 * Number of discard segments (or ranges) the driver needs to fill in. 1212 * Each discard bio merged into a request is counted as one segment. 1213 */ 1214 static inline unsigned short blk_rq_nr_discard_segments(struct request *rq) 1215 { 1216 return max_t(unsigned short, rq->nr_phys_segments, 1); 1217 } 1218 1219 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 1220 extern void blk_dump_rq_flags(struct request *, char *); 1221 extern long nr_blockdev_pages(void); 1222 1223 bool __must_check blk_get_queue(struct request_queue *); 1224 struct request_queue *blk_alloc_queue(gfp_t); 1225 struct request_queue *blk_alloc_queue_node(gfp_t, int); 1226 extern void blk_put_queue(struct request_queue *); 1227 extern void blk_set_queue_dying(struct request_queue *); 1228 1229 /* 1230 * block layer runtime pm functions 1231 */ 1232 #ifdef CONFIG_PM 1233 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev); 1234 extern int blk_pre_runtime_suspend(struct request_queue *q); 1235 extern void blk_post_runtime_suspend(struct request_queue *q, int err); 1236 extern void blk_pre_runtime_resume(struct request_queue *q); 1237 extern void blk_post_runtime_resume(struct request_queue *q, int err); 1238 extern void blk_set_runtime_active(struct request_queue *q); 1239 #else 1240 static inline void blk_pm_runtime_init(struct request_queue *q, 1241 struct device *dev) {} 1242 static inline int blk_pre_runtime_suspend(struct request_queue *q) 1243 { 1244 return -ENOSYS; 1245 } 1246 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {} 1247 static inline void blk_pre_runtime_resume(struct request_queue *q) {} 1248 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {} 1249 static inline void blk_set_runtime_active(struct request_queue *q) {} 1250 #endif 1251 1252 /* 1253 * blk_plug permits building a queue of related requests by holding the I/O 1254 * fragments for a short period. This allows merging of sequential requests 1255 * into single larger request. As the requests are moved from a per-task list to 1256 * the device's request_queue in a batch, this results in improved scalability 1257 * as the lock contention for request_queue lock is reduced. 1258 * 1259 * It is ok not to disable preemption when adding the request to the plug list 1260 * or when attempting a merge, because blk_schedule_flush_list() will only flush 1261 * the plug list when the task sleeps by itself. For details, please see 1262 * schedule() where blk_schedule_flush_plug() is called. 1263 */ 1264 struct blk_plug { 1265 struct list_head list; /* requests */ 1266 struct list_head mq_list; /* blk-mq requests */ 1267 struct list_head cb_list; /* md requires an unplug callback */ 1268 }; 1269 #define BLK_MAX_REQUEST_COUNT 16 1270 #define BLK_PLUG_FLUSH_SIZE (128 * 1024) 1271 1272 struct blk_plug_cb; 1273 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool); 1274 struct blk_plug_cb { 1275 struct list_head list; 1276 blk_plug_cb_fn callback; 1277 void *data; 1278 }; 1279 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, 1280 void *data, int size); 1281 extern void blk_start_plug(struct blk_plug *); 1282 extern void blk_finish_plug(struct blk_plug *); 1283 extern void blk_flush_plug_list(struct blk_plug *, bool); 1284 1285 static inline void blk_flush_plug(struct task_struct *tsk) 1286 { 1287 struct blk_plug *plug = tsk->plug; 1288 1289 if (plug) 1290 blk_flush_plug_list(plug, false); 1291 } 1292 1293 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 1294 { 1295 struct blk_plug *plug = tsk->plug; 1296 1297 if (plug) 1298 blk_flush_plug_list(plug, true); 1299 } 1300 1301 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1302 { 1303 struct blk_plug *plug = tsk->plug; 1304 1305 return plug && 1306 (!list_empty(&plug->list) || 1307 !list_empty(&plug->mq_list) || 1308 !list_empty(&plug->cb_list)); 1309 } 1310 1311 /* 1312 * tag stuff 1313 */ 1314 extern int blk_queue_start_tag(struct request_queue *, struct request *); 1315 extern struct request *blk_queue_find_tag(struct request_queue *, int); 1316 extern void blk_queue_end_tag(struct request_queue *, struct request *); 1317 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int); 1318 extern void blk_queue_free_tags(struct request_queue *); 1319 extern int blk_queue_resize_tags(struct request_queue *, int); 1320 extern void blk_queue_invalidate_tags(struct request_queue *); 1321 extern struct blk_queue_tag *blk_init_tags(int, int); 1322 extern void blk_free_tags(struct blk_queue_tag *); 1323 1324 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 1325 int tag) 1326 { 1327 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 1328 return NULL; 1329 return bqt->tag_index[tag]; 1330 } 1331 1332 1333 #define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */ 1334 #define BLKDEV_DISCARD_ZERO (1 << 1) /* must reliably zero data */ 1335 1336 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 1337 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1338 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 1339 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1340 sector_t nr_sects, gfp_t gfp_mask, int flags, 1341 struct bio **biop); 1342 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, 1343 sector_t nr_sects, gfp_t gfp_mask, struct page *page); 1344 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1345 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop, 1346 bool discard); 1347 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1348 sector_t nr_sects, gfp_t gfp_mask, bool discard); 1349 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 1350 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 1351 { 1352 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 1353 nr_blocks << (sb->s_blocksize_bits - 9), 1354 gfp_mask, flags); 1355 } 1356 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 1357 sector_t nr_blocks, gfp_t gfp_mask) 1358 { 1359 return blkdev_issue_zeroout(sb->s_bdev, 1360 block << (sb->s_blocksize_bits - 9), 1361 nr_blocks << (sb->s_blocksize_bits - 9), 1362 gfp_mask, true); 1363 } 1364 1365 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 1366 1367 enum blk_default_limits { 1368 BLK_MAX_SEGMENTS = 128, 1369 BLK_SAFE_MAX_SECTORS = 255, 1370 BLK_DEF_MAX_SECTORS = 2560, 1371 BLK_MAX_SEGMENT_SIZE = 65536, 1372 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 1373 }; 1374 1375 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1376 1377 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 1378 { 1379 return q->limits.bounce_pfn; 1380 } 1381 1382 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1383 { 1384 return q->limits.seg_boundary_mask; 1385 } 1386 1387 static inline unsigned long queue_virt_boundary(struct request_queue *q) 1388 { 1389 return q->limits.virt_boundary_mask; 1390 } 1391 1392 static inline unsigned int queue_max_sectors(struct request_queue *q) 1393 { 1394 return q->limits.max_sectors; 1395 } 1396 1397 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1398 { 1399 return q->limits.max_hw_sectors; 1400 } 1401 1402 static inline unsigned short queue_max_segments(struct request_queue *q) 1403 { 1404 return q->limits.max_segments; 1405 } 1406 1407 static inline unsigned short queue_max_discard_segments(struct request_queue *q) 1408 { 1409 return q->limits.max_discard_segments; 1410 } 1411 1412 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1413 { 1414 return q->limits.max_segment_size; 1415 } 1416 1417 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1418 { 1419 int retval = 512; 1420 1421 if (q && q->limits.logical_block_size) 1422 retval = q->limits.logical_block_size; 1423 1424 return retval; 1425 } 1426 1427 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1428 { 1429 return queue_logical_block_size(bdev_get_queue(bdev)); 1430 } 1431 1432 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1433 { 1434 return q->limits.physical_block_size; 1435 } 1436 1437 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1438 { 1439 return queue_physical_block_size(bdev_get_queue(bdev)); 1440 } 1441 1442 static inline unsigned int queue_io_min(struct request_queue *q) 1443 { 1444 return q->limits.io_min; 1445 } 1446 1447 static inline int bdev_io_min(struct block_device *bdev) 1448 { 1449 return queue_io_min(bdev_get_queue(bdev)); 1450 } 1451 1452 static inline unsigned int queue_io_opt(struct request_queue *q) 1453 { 1454 return q->limits.io_opt; 1455 } 1456 1457 static inline int bdev_io_opt(struct block_device *bdev) 1458 { 1459 return queue_io_opt(bdev_get_queue(bdev)); 1460 } 1461 1462 static inline int queue_alignment_offset(struct request_queue *q) 1463 { 1464 if (q->limits.misaligned) 1465 return -1; 1466 1467 return q->limits.alignment_offset; 1468 } 1469 1470 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1471 { 1472 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1473 unsigned int alignment = sector_div(sector, granularity >> 9) << 9; 1474 1475 return (granularity + lim->alignment_offset - alignment) % granularity; 1476 } 1477 1478 static inline int bdev_alignment_offset(struct block_device *bdev) 1479 { 1480 struct request_queue *q = bdev_get_queue(bdev); 1481 1482 if (q->limits.misaligned) 1483 return -1; 1484 1485 if (bdev != bdev->bd_contains) 1486 return bdev->bd_part->alignment_offset; 1487 1488 return q->limits.alignment_offset; 1489 } 1490 1491 static inline int queue_discard_alignment(struct request_queue *q) 1492 { 1493 if (q->limits.discard_misaligned) 1494 return -1; 1495 1496 return q->limits.discard_alignment; 1497 } 1498 1499 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1500 { 1501 unsigned int alignment, granularity, offset; 1502 1503 if (!lim->max_discard_sectors) 1504 return 0; 1505 1506 /* Why are these in bytes, not sectors? */ 1507 alignment = lim->discard_alignment >> 9; 1508 granularity = lim->discard_granularity >> 9; 1509 if (!granularity) 1510 return 0; 1511 1512 /* Offset of the partition start in 'granularity' sectors */ 1513 offset = sector_div(sector, granularity); 1514 1515 /* And why do we do this modulus *again* in blkdev_issue_discard()? */ 1516 offset = (granularity + alignment - offset) % granularity; 1517 1518 /* Turn it back into bytes, gaah */ 1519 return offset << 9; 1520 } 1521 1522 static inline int bdev_discard_alignment(struct block_device *bdev) 1523 { 1524 struct request_queue *q = bdev_get_queue(bdev); 1525 1526 if (bdev != bdev->bd_contains) 1527 return bdev->bd_part->discard_alignment; 1528 1529 return q->limits.discard_alignment; 1530 } 1531 1532 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1533 { 1534 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) 1535 return 1; 1536 1537 return 0; 1538 } 1539 1540 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1541 { 1542 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1543 } 1544 1545 static inline unsigned int bdev_write_same(struct block_device *bdev) 1546 { 1547 struct request_queue *q = bdev_get_queue(bdev); 1548 1549 if (q) 1550 return q->limits.max_write_same_sectors; 1551 1552 return 0; 1553 } 1554 1555 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev) 1556 { 1557 struct request_queue *q = bdev_get_queue(bdev); 1558 1559 if (q) 1560 return q->limits.max_write_zeroes_sectors; 1561 1562 return 0; 1563 } 1564 1565 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev) 1566 { 1567 struct request_queue *q = bdev_get_queue(bdev); 1568 1569 if (q) 1570 return blk_queue_zoned_model(q); 1571 1572 return BLK_ZONED_NONE; 1573 } 1574 1575 static inline bool bdev_is_zoned(struct block_device *bdev) 1576 { 1577 struct request_queue *q = bdev_get_queue(bdev); 1578 1579 if (q) 1580 return blk_queue_is_zoned(q); 1581 1582 return false; 1583 } 1584 1585 static inline unsigned int bdev_zone_sectors(struct block_device *bdev) 1586 { 1587 struct request_queue *q = bdev_get_queue(bdev); 1588 1589 if (q) 1590 return blk_queue_zone_sectors(q); 1591 1592 return 0; 1593 } 1594 1595 static inline int queue_dma_alignment(struct request_queue *q) 1596 { 1597 return q ? q->dma_alignment : 511; 1598 } 1599 1600 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1601 unsigned int len) 1602 { 1603 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1604 return !(addr & alignment) && !(len & alignment); 1605 } 1606 1607 /* assumes size > 256 */ 1608 static inline unsigned int blksize_bits(unsigned int size) 1609 { 1610 unsigned int bits = 8; 1611 do { 1612 bits++; 1613 size >>= 1; 1614 } while (size > 256); 1615 return bits; 1616 } 1617 1618 static inline unsigned int block_size(struct block_device *bdev) 1619 { 1620 return bdev->bd_block_size; 1621 } 1622 1623 static inline bool queue_flush_queueable(struct request_queue *q) 1624 { 1625 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags); 1626 } 1627 1628 typedef struct {struct page *v;} Sector; 1629 1630 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1631 1632 static inline void put_dev_sector(Sector p) 1633 { 1634 put_page(p.v); 1635 } 1636 1637 static inline bool __bvec_gap_to_prev(struct request_queue *q, 1638 struct bio_vec *bprv, unsigned int offset) 1639 { 1640 return offset || 1641 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); 1642 } 1643 1644 /* 1645 * Check if adding a bio_vec after bprv with offset would create a gap in 1646 * the SG list. Most drivers don't care about this, but some do. 1647 */ 1648 static inline bool bvec_gap_to_prev(struct request_queue *q, 1649 struct bio_vec *bprv, unsigned int offset) 1650 { 1651 if (!queue_virt_boundary(q)) 1652 return false; 1653 return __bvec_gap_to_prev(q, bprv, offset); 1654 } 1655 1656 /* 1657 * Check if the two bvecs from two bios can be merged to one segment. 1658 * If yes, no need to check gap between the two bios since the 1st bio 1659 * and the 1st bvec in the 2nd bio can be handled in one segment. 1660 */ 1661 static inline bool bios_segs_mergeable(struct request_queue *q, 1662 struct bio *prev, struct bio_vec *prev_last_bv, 1663 struct bio_vec *next_first_bv) 1664 { 1665 if (!BIOVEC_PHYS_MERGEABLE(prev_last_bv, next_first_bv)) 1666 return false; 1667 if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv)) 1668 return false; 1669 if (prev->bi_seg_back_size + next_first_bv->bv_len > 1670 queue_max_segment_size(q)) 1671 return false; 1672 return true; 1673 } 1674 1675 static inline bool bio_will_gap(struct request_queue *q, 1676 struct request *prev_rq, 1677 struct bio *prev, 1678 struct bio *next) 1679 { 1680 if (bio_has_data(prev) && queue_virt_boundary(q)) { 1681 struct bio_vec pb, nb; 1682 1683 /* 1684 * don't merge if the 1st bio starts with non-zero 1685 * offset, otherwise it is quite difficult to respect 1686 * sg gap limit. We work hard to merge a huge number of small 1687 * single bios in case of mkfs. 1688 */ 1689 if (prev_rq) 1690 bio_get_first_bvec(prev_rq->bio, &pb); 1691 else 1692 bio_get_first_bvec(prev, &pb); 1693 if (pb.bv_offset) 1694 return true; 1695 1696 /* 1697 * We don't need to worry about the situation that the 1698 * merged segment ends in unaligned virt boundary: 1699 * 1700 * - if 'pb' ends aligned, the merged segment ends aligned 1701 * - if 'pb' ends unaligned, the next bio must include 1702 * one single bvec of 'nb', otherwise the 'nb' can't 1703 * merge with 'pb' 1704 */ 1705 bio_get_last_bvec(prev, &pb); 1706 bio_get_first_bvec(next, &nb); 1707 1708 if (!bios_segs_mergeable(q, prev, &pb, &nb)) 1709 return __bvec_gap_to_prev(q, &pb, nb.bv_offset); 1710 } 1711 1712 return false; 1713 } 1714 1715 static inline bool req_gap_back_merge(struct request *req, struct bio *bio) 1716 { 1717 return bio_will_gap(req->q, req, req->biotail, bio); 1718 } 1719 1720 static inline bool req_gap_front_merge(struct request *req, struct bio *bio) 1721 { 1722 return bio_will_gap(req->q, NULL, bio, req->bio); 1723 } 1724 1725 int kblockd_schedule_work(struct work_struct *work); 1726 int kblockd_schedule_work_on(int cpu, struct work_struct *work); 1727 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay); 1728 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay); 1729 1730 #ifdef CONFIG_BLK_CGROUP 1731 /* 1732 * This should not be using sched_clock(). A real patch is in progress 1733 * to fix this up, until that is in place we need to disable preemption 1734 * around sched_clock() in this function and set_io_start_time_ns(). 1735 */ 1736 static inline void set_start_time_ns(struct request *req) 1737 { 1738 preempt_disable(); 1739 req->start_time_ns = sched_clock(); 1740 preempt_enable(); 1741 } 1742 1743 static inline void set_io_start_time_ns(struct request *req) 1744 { 1745 preempt_disable(); 1746 req->io_start_time_ns = sched_clock(); 1747 preempt_enable(); 1748 } 1749 1750 static inline uint64_t rq_start_time_ns(struct request *req) 1751 { 1752 return req->start_time_ns; 1753 } 1754 1755 static inline uint64_t rq_io_start_time_ns(struct request *req) 1756 { 1757 return req->io_start_time_ns; 1758 } 1759 #else 1760 static inline void set_start_time_ns(struct request *req) {} 1761 static inline void set_io_start_time_ns(struct request *req) {} 1762 static inline uint64_t rq_start_time_ns(struct request *req) 1763 { 1764 return 0; 1765 } 1766 static inline uint64_t rq_io_start_time_ns(struct request *req) 1767 { 1768 return 0; 1769 } 1770 #endif 1771 1772 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1773 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1774 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1775 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1776 1777 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1778 1779 enum blk_integrity_flags { 1780 BLK_INTEGRITY_VERIFY = 1 << 0, 1781 BLK_INTEGRITY_GENERATE = 1 << 1, 1782 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2, 1783 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3, 1784 }; 1785 1786 struct blk_integrity_iter { 1787 void *prot_buf; 1788 void *data_buf; 1789 sector_t seed; 1790 unsigned int data_size; 1791 unsigned short interval; 1792 const char *disk_name; 1793 }; 1794 1795 typedef int (integrity_processing_fn) (struct blk_integrity_iter *); 1796 1797 struct blk_integrity_profile { 1798 integrity_processing_fn *generate_fn; 1799 integrity_processing_fn *verify_fn; 1800 const char *name; 1801 }; 1802 1803 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *); 1804 extern void blk_integrity_unregister(struct gendisk *); 1805 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1806 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1807 struct scatterlist *); 1808 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1809 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, 1810 struct request *); 1811 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, 1812 struct bio *); 1813 1814 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1815 { 1816 struct blk_integrity *bi = &disk->queue->integrity; 1817 1818 if (!bi->profile) 1819 return NULL; 1820 1821 return bi; 1822 } 1823 1824 static inline 1825 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1826 { 1827 return blk_get_integrity(bdev->bd_disk); 1828 } 1829 1830 static inline bool blk_integrity_rq(struct request *rq) 1831 { 1832 return rq->cmd_flags & REQ_INTEGRITY; 1833 } 1834 1835 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1836 unsigned int segs) 1837 { 1838 q->limits.max_integrity_segments = segs; 1839 } 1840 1841 static inline unsigned short 1842 queue_max_integrity_segments(struct request_queue *q) 1843 { 1844 return q->limits.max_integrity_segments; 1845 } 1846 1847 static inline bool integrity_req_gap_back_merge(struct request *req, 1848 struct bio *next) 1849 { 1850 struct bio_integrity_payload *bip = bio_integrity(req->bio); 1851 struct bio_integrity_payload *bip_next = bio_integrity(next); 1852 1853 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1854 bip_next->bip_vec[0].bv_offset); 1855 } 1856 1857 static inline bool integrity_req_gap_front_merge(struct request *req, 1858 struct bio *bio) 1859 { 1860 struct bio_integrity_payload *bip = bio_integrity(bio); 1861 struct bio_integrity_payload *bip_next = bio_integrity(req->bio); 1862 1863 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1864 bip_next->bip_vec[0].bv_offset); 1865 } 1866 1867 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1868 1869 struct bio; 1870 struct block_device; 1871 struct gendisk; 1872 struct blk_integrity; 1873 1874 static inline int blk_integrity_rq(struct request *rq) 1875 { 1876 return 0; 1877 } 1878 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1879 struct bio *b) 1880 { 1881 return 0; 1882 } 1883 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1884 struct bio *b, 1885 struct scatterlist *s) 1886 { 1887 return 0; 1888 } 1889 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1890 { 1891 return NULL; 1892 } 1893 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1894 { 1895 return NULL; 1896 } 1897 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1898 { 1899 return 0; 1900 } 1901 static inline void blk_integrity_register(struct gendisk *d, 1902 struct blk_integrity *b) 1903 { 1904 } 1905 static inline void blk_integrity_unregister(struct gendisk *d) 1906 { 1907 } 1908 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1909 unsigned int segs) 1910 { 1911 } 1912 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1913 { 1914 return 0; 1915 } 1916 static inline bool blk_integrity_merge_rq(struct request_queue *rq, 1917 struct request *r1, 1918 struct request *r2) 1919 { 1920 return true; 1921 } 1922 static inline bool blk_integrity_merge_bio(struct request_queue *rq, 1923 struct request *r, 1924 struct bio *b) 1925 { 1926 return true; 1927 } 1928 1929 static inline bool integrity_req_gap_back_merge(struct request *req, 1930 struct bio *next) 1931 { 1932 return false; 1933 } 1934 static inline bool integrity_req_gap_front_merge(struct request *req, 1935 struct bio *bio) 1936 { 1937 return false; 1938 } 1939 1940 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1941 1942 /** 1943 * struct blk_dax_ctl - control and output parameters for ->direct_access 1944 * @sector: (input) offset relative to a block_device 1945 * @addr: (output) kernel virtual address for @sector populated by driver 1946 * @pfn: (output) page frame number for @addr populated by driver 1947 * @size: (input) number of bytes requested 1948 */ 1949 struct blk_dax_ctl { 1950 sector_t sector; 1951 void *addr; 1952 long size; 1953 pfn_t pfn; 1954 }; 1955 1956 struct block_device_operations { 1957 int (*open) (struct block_device *, fmode_t); 1958 void (*release) (struct gendisk *, fmode_t); 1959 int (*rw_page)(struct block_device *, sector_t, struct page *, bool); 1960 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1961 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1962 long (*direct_access)(struct block_device *, sector_t, void **, pfn_t *, 1963 long); 1964 unsigned int (*check_events) (struct gendisk *disk, 1965 unsigned int clearing); 1966 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1967 int (*media_changed) (struct gendisk *); 1968 void (*unlock_native_capacity) (struct gendisk *); 1969 int (*revalidate_disk) (struct gendisk *); 1970 int (*getgeo)(struct block_device *, struct hd_geometry *); 1971 /* this callback is with swap_lock and sometimes page table lock held */ 1972 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1973 struct module *owner; 1974 const struct pr_ops *pr_ops; 1975 }; 1976 1977 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1978 unsigned long); 1979 extern int bdev_read_page(struct block_device *, sector_t, struct page *); 1980 extern int bdev_write_page(struct block_device *, sector_t, struct page *, 1981 struct writeback_control *); 1982 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *); 1983 extern int bdev_dax_supported(struct super_block *, int); 1984 extern bool bdev_dax_capable(struct block_device *); 1985 #else /* CONFIG_BLOCK */ 1986 1987 struct block_device; 1988 1989 /* 1990 * stubs for when the block layer is configured out 1991 */ 1992 #define buffer_heads_over_limit 0 1993 1994 static inline long nr_blockdev_pages(void) 1995 { 1996 return 0; 1997 } 1998 1999 struct blk_plug { 2000 }; 2001 2002 static inline void blk_start_plug(struct blk_plug *plug) 2003 { 2004 } 2005 2006 static inline void blk_finish_plug(struct blk_plug *plug) 2007 { 2008 } 2009 2010 static inline void blk_flush_plug(struct task_struct *task) 2011 { 2012 } 2013 2014 static inline void blk_schedule_flush_plug(struct task_struct *task) 2015 { 2016 } 2017 2018 2019 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 2020 { 2021 return false; 2022 } 2023 2024 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, 2025 sector_t *error_sector) 2026 { 2027 return 0; 2028 } 2029 2030 #endif /* CONFIG_BLOCK */ 2031 2032 #endif 2033