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