1 #ifndef _LINUX_BLKDEV_H 2 #define _LINUX_BLKDEV_H 3 4 #include <linux/sched.h> 5 6 #ifdef CONFIG_BLOCK 7 8 #include <linux/major.h> 9 #include <linux/genhd.h> 10 #include <linux/list.h> 11 #include <linux/llist.h> 12 #include <linux/timer.h> 13 #include <linux/workqueue.h> 14 #include <linux/pagemap.h> 15 #include <linux/backing-dev-defs.h> 16 #include <linux/wait.h> 17 #include <linux/mempool.h> 18 #include <linux/pfn.h> 19 #include <linux/bio.h> 20 #include <linux/stringify.h> 21 #include <linux/gfp.h> 22 #include <linux/bsg.h> 23 #include <linux/smp.h> 24 #include <linux/rcupdate.h> 25 #include <linux/percpu-refcount.h> 26 #include <linux/scatterlist.h> 27 28 struct module; 29 struct scsi_ioctl_command; 30 31 struct request_queue; 32 struct elevator_queue; 33 struct blk_trace; 34 struct request; 35 struct sg_io_hdr; 36 struct bsg_job; 37 struct blkcg_gq; 38 struct blk_flush_queue; 39 struct pr_ops; 40 41 #define BLKDEV_MIN_RQ 4 42 #define BLKDEV_MAX_RQ 128 /* Default maximum */ 43 44 /* 45 * Maximum number of blkcg policies allowed to be registered concurrently. 46 * Defined here to simplify include dependency. 47 */ 48 #define BLKCG_MAX_POLS 2 49 50 struct request; 51 typedef void (rq_end_io_fn)(struct request *, int); 52 53 #define BLK_RL_SYNCFULL (1U << 0) 54 #define BLK_RL_ASYNCFULL (1U << 1) 55 56 struct request_list { 57 struct request_queue *q; /* the queue this rl belongs to */ 58 #ifdef CONFIG_BLK_CGROUP 59 struct blkcg_gq *blkg; /* blkg this request pool belongs to */ 60 #endif 61 /* 62 * count[], starved[], and wait[] are indexed by 63 * BLK_RW_SYNC/BLK_RW_ASYNC 64 */ 65 int count[2]; 66 int starved[2]; 67 mempool_t *rq_pool; 68 wait_queue_head_t wait[2]; 69 unsigned int flags; 70 }; 71 72 /* 73 * request command types 74 */ 75 enum rq_cmd_type_bits { 76 REQ_TYPE_FS = 1, /* fs request */ 77 REQ_TYPE_BLOCK_PC, /* scsi command */ 78 REQ_TYPE_DRV_PRIV, /* driver defined types from here */ 79 }; 80 81 #define BLK_MAX_CDB 16 82 83 /* 84 * Try to put the fields that are referenced together in the same cacheline. 85 * 86 * If you modify this structure, make sure to update blk_rq_init() and 87 * especially blk_mq_rq_ctx_init() to take care of the added fields. 88 */ 89 struct request { 90 struct list_head queuelist; 91 union { 92 struct call_single_data csd; 93 unsigned long fifo_time; 94 }; 95 96 struct request_queue *q; 97 struct blk_mq_ctx *mq_ctx; 98 99 u64 cmd_flags; 100 unsigned cmd_type; 101 unsigned long atomic_flags; 102 103 int cpu; 104 105 /* the following two fields are internal, NEVER access directly */ 106 unsigned int __data_len; /* total data len */ 107 sector_t __sector; /* sector cursor */ 108 109 struct bio *bio; 110 struct bio *biotail; 111 112 /* 113 * The hash is used inside the scheduler, and killed once the 114 * request reaches the dispatch list. The ipi_list is only used 115 * to queue the request for softirq completion, which is long 116 * after the request has been unhashed (and even removed from 117 * the dispatch list). 118 */ 119 union { 120 struct hlist_node hash; /* merge hash */ 121 struct list_head ipi_list; 122 }; 123 124 /* 125 * The rb_node is only used inside the io scheduler, requests 126 * are pruned when moved to the dispatch queue. So let the 127 * completion_data share space with the rb_node. 128 */ 129 union { 130 struct rb_node rb_node; /* sort/lookup */ 131 void *completion_data; 132 }; 133 134 /* 135 * Three pointers are available for the IO schedulers, if they need 136 * more they have to dynamically allocate it. Flush requests are 137 * never put on the IO scheduler. So let the flush fields share 138 * space with the elevator data. 139 */ 140 union { 141 struct { 142 struct io_cq *icq; 143 void *priv[2]; 144 } elv; 145 146 struct { 147 unsigned int seq; 148 struct list_head list; 149 rq_end_io_fn *saved_end_io; 150 } flush; 151 }; 152 153 struct gendisk *rq_disk; 154 struct hd_struct *part; 155 unsigned long start_time; 156 #ifdef CONFIG_BLK_CGROUP 157 struct request_list *rl; /* rl this rq is alloced from */ 158 unsigned long long start_time_ns; 159 unsigned long long io_start_time_ns; /* when passed to hardware */ 160 #endif 161 /* Number of scatter-gather DMA addr+len pairs after 162 * physical address coalescing is performed. 163 */ 164 unsigned short nr_phys_segments; 165 #if defined(CONFIG_BLK_DEV_INTEGRITY) 166 unsigned short nr_integrity_segments; 167 #endif 168 169 unsigned short ioprio; 170 171 void *special; /* opaque pointer available for LLD use */ 172 173 int tag; 174 int errors; 175 176 /* 177 * when request is used as a packet command carrier 178 */ 179 unsigned char __cmd[BLK_MAX_CDB]; 180 unsigned char *cmd; 181 unsigned short cmd_len; 182 183 unsigned int extra_len; /* length of alignment and padding */ 184 unsigned int sense_len; 185 unsigned int resid_len; /* residual count */ 186 void *sense; 187 188 unsigned long deadline; 189 struct list_head timeout_list; 190 unsigned int timeout; 191 int retries; 192 193 /* 194 * completion callback. 195 */ 196 rq_end_io_fn *end_io; 197 void *end_io_data; 198 199 /* for bidi */ 200 struct request *next_rq; 201 }; 202 203 static inline unsigned short req_get_ioprio(struct request *req) 204 { 205 return req->ioprio; 206 } 207 208 #include <linux/elevator.h> 209 210 struct blk_queue_ctx; 211 212 typedef void (request_fn_proc) (struct request_queue *q); 213 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio); 214 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 215 typedef void (unprep_rq_fn) (struct request_queue *, struct request *); 216 217 struct bio_vec; 218 typedef void (softirq_done_fn)(struct request *); 219 typedef int (dma_drain_needed_fn)(struct request *); 220 typedef int (lld_busy_fn) (struct request_queue *q); 221 typedef int (bsg_job_fn) (struct bsg_job *); 222 223 enum blk_eh_timer_return { 224 BLK_EH_NOT_HANDLED, 225 BLK_EH_HANDLED, 226 BLK_EH_RESET_TIMER, 227 }; 228 229 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 230 231 enum blk_queue_state { 232 Queue_down, 233 Queue_up, 234 }; 235 236 struct blk_queue_tag { 237 struct request **tag_index; /* map of busy tags */ 238 unsigned long *tag_map; /* bit map of free/busy tags */ 239 int busy; /* current depth */ 240 int max_depth; /* what we will send to device */ 241 int real_max_depth; /* what the array can hold */ 242 atomic_t refcnt; /* map can be shared */ 243 int alloc_policy; /* tag allocation policy */ 244 int next_tag; /* next tag */ 245 }; 246 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */ 247 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */ 248 249 #define BLK_SCSI_MAX_CMDS (256) 250 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 251 252 struct queue_limits { 253 unsigned long bounce_pfn; 254 unsigned long seg_boundary_mask; 255 unsigned long virt_boundary_mask; 256 257 unsigned int max_hw_sectors; 258 unsigned int max_dev_sectors; 259 unsigned int chunk_sectors; 260 unsigned int max_sectors; 261 unsigned int max_segment_size; 262 unsigned int physical_block_size; 263 unsigned int alignment_offset; 264 unsigned int io_min; 265 unsigned int io_opt; 266 unsigned int max_discard_sectors; 267 unsigned int max_hw_discard_sectors; 268 unsigned int max_write_same_sectors; 269 unsigned int discard_granularity; 270 unsigned int discard_alignment; 271 272 unsigned short logical_block_size; 273 unsigned short max_segments; 274 unsigned short max_integrity_segments; 275 276 unsigned char misaligned; 277 unsigned char discard_misaligned; 278 unsigned char cluster; 279 unsigned char discard_zeroes_data; 280 unsigned char raid_partial_stripes_expensive; 281 }; 282 283 struct request_queue { 284 /* 285 * Together with queue_head for cacheline sharing 286 */ 287 struct list_head queue_head; 288 struct request *last_merge; 289 struct elevator_queue *elevator; 290 int nr_rqs[2]; /* # allocated [a]sync rqs */ 291 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */ 292 293 /* 294 * If blkcg is not used, @q->root_rl serves all requests. If blkcg 295 * is used, root blkg allocates from @q->root_rl and all other 296 * blkgs from their own blkg->rl. Which one to use should be 297 * determined using bio_request_list(). 298 */ 299 struct request_list root_rl; 300 301 request_fn_proc *request_fn; 302 make_request_fn *make_request_fn; 303 prep_rq_fn *prep_rq_fn; 304 unprep_rq_fn *unprep_rq_fn; 305 softirq_done_fn *softirq_done_fn; 306 rq_timed_out_fn *rq_timed_out_fn; 307 dma_drain_needed_fn *dma_drain_needed; 308 lld_busy_fn *lld_busy_fn; 309 310 struct blk_mq_ops *mq_ops; 311 312 unsigned int *mq_map; 313 314 /* sw queues */ 315 struct blk_mq_ctx __percpu *queue_ctx; 316 unsigned int nr_queues; 317 318 /* hw dispatch queues */ 319 struct blk_mq_hw_ctx **queue_hw_ctx; 320 unsigned int nr_hw_queues; 321 322 /* 323 * Dispatch queue sorting 324 */ 325 sector_t end_sector; 326 struct request *boundary_rq; 327 328 /* 329 * Delayed queue handling 330 */ 331 struct delayed_work delay_work; 332 333 struct backing_dev_info backing_dev_info; 334 335 /* 336 * The queue owner gets to use this for whatever they like. 337 * ll_rw_blk doesn't touch it. 338 */ 339 void *queuedata; 340 341 /* 342 * various queue flags, see QUEUE_* below 343 */ 344 unsigned long queue_flags; 345 346 /* 347 * ida allocated id for this queue. Used to index queues from 348 * ioctx. 349 */ 350 int id; 351 352 /* 353 * queue needs bounce pages for pages above this limit 354 */ 355 gfp_t bounce_gfp; 356 357 /* 358 * protects queue structures from reentrancy. ->__queue_lock should 359 * _never_ be used directly, it is queue private. always use 360 * ->queue_lock. 361 */ 362 spinlock_t __queue_lock; 363 spinlock_t *queue_lock; 364 365 /* 366 * queue kobject 367 */ 368 struct kobject kobj; 369 370 /* 371 * mq queue kobject 372 */ 373 struct kobject mq_kobj; 374 375 #ifdef CONFIG_BLK_DEV_INTEGRITY 376 struct blk_integrity integrity; 377 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 378 379 #ifdef CONFIG_PM 380 struct device *dev; 381 int rpm_status; 382 unsigned int nr_pending; 383 #endif 384 385 /* 386 * queue settings 387 */ 388 unsigned long nr_requests; /* Max # of requests */ 389 unsigned int nr_congestion_on; 390 unsigned int nr_congestion_off; 391 unsigned int nr_batching; 392 393 unsigned int dma_drain_size; 394 void *dma_drain_buffer; 395 unsigned int dma_pad_mask; 396 unsigned int dma_alignment; 397 398 struct blk_queue_tag *queue_tags; 399 struct list_head tag_busy_list; 400 401 unsigned int nr_sorted; 402 unsigned int in_flight[2]; 403 /* 404 * Number of active block driver functions for which blk_drain_queue() 405 * must wait. Must be incremented around functions that unlock the 406 * queue_lock internally, e.g. scsi_request_fn(). 407 */ 408 unsigned int request_fn_active; 409 410 unsigned int rq_timeout; 411 struct timer_list timeout; 412 struct list_head timeout_list; 413 414 struct list_head icq_list; 415 #ifdef CONFIG_BLK_CGROUP 416 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); 417 struct blkcg_gq *root_blkg; 418 struct list_head blkg_list; 419 #endif 420 421 struct queue_limits limits; 422 423 /* 424 * sg stuff 425 */ 426 unsigned int sg_timeout; 427 unsigned int sg_reserved_size; 428 int node; 429 #ifdef CONFIG_BLK_DEV_IO_TRACE 430 struct blk_trace *blk_trace; 431 #endif 432 /* 433 * for flush operations 434 */ 435 unsigned int flush_flags; 436 unsigned int flush_not_queueable:1; 437 struct blk_flush_queue *fq; 438 439 struct list_head requeue_list; 440 spinlock_t requeue_lock; 441 struct work_struct requeue_work; 442 443 struct mutex sysfs_lock; 444 445 int bypass_depth; 446 atomic_t mq_freeze_depth; 447 448 #if defined(CONFIG_BLK_DEV_BSG) 449 bsg_job_fn *bsg_job_fn; 450 int bsg_job_size; 451 struct bsg_class_device bsg_dev; 452 #endif 453 454 #ifdef CONFIG_BLK_DEV_THROTTLING 455 /* Throttle data */ 456 struct throtl_data *td; 457 #endif 458 struct rcu_head rcu_head; 459 wait_queue_head_t mq_freeze_wq; 460 struct percpu_ref q_usage_counter; 461 struct list_head all_q_node; 462 463 struct blk_mq_tag_set *tag_set; 464 struct list_head tag_set_list; 465 struct bio_set *bio_split; 466 467 bool mq_sysfs_init_done; 468 }; 469 470 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 471 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 472 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 473 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 474 #define QUEUE_FLAG_DYING 5 /* queue being torn down */ 475 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */ 476 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ 477 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ 478 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ 479 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ 480 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ 481 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ 482 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 483 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ 484 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ 485 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ 486 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ 487 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */ 488 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ 489 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */ 490 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */ 491 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/ 492 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */ 493 494 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 495 (1 << QUEUE_FLAG_STACKABLE) | \ 496 (1 << QUEUE_FLAG_SAME_COMP) | \ 497 (1 << QUEUE_FLAG_ADD_RANDOM)) 498 499 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 500 (1 << QUEUE_FLAG_STACKABLE) | \ 501 (1 << QUEUE_FLAG_SAME_COMP)) 502 503 static inline void queue_lockdep_assert_held(struct request_queue *q) 504 { 505 if (q->queue_lock) 506 lockdep_assert_held(q->queue_lock); 507 } 508 509 static inline void queue_flag_set_unlocked(unsigned int flag, 510 struct request_queue *q) 511 { 512 __set_bit(flag, &q->queue_flags); 513 } 514 515 static inline int queue_flag_test_and_clear(unsigned int flag, 516 struct request_queue *q) 517 { 518 queue_lockdep_assert_held(q); 519 520 if (test_bit(flag, &q->queue_flags)) { 521 __clear_bit(flag, &q->queue_flags); 522 return 1; 523 } 524 525 return 0; 526 } 527 528 static inline int queue_flag_test_and_set(unsigned int flag, 529 struct request_queue *q) 530 { 531 queue_lockdep_assert_held(q); 532 533 if (!test_bit(flag, &q->queue_flags)) { 534 __set_bit(flag, &q->queue_flags); 535 return 0; 536 } 537 538 return 1; 539 } 540 541 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 542 { 543 queue_lockdep_assert_held(q); 544 __set_bit(flag, &q->queue_flags); 545 } 546 547 static inline void queue_flag_clear_unlocked(unsigned int flag, 548 struct request_queue *q) 549 { 550 __clear_bit(flag, &q->queue_flags); 551 } 552 553 static inline int queue_in_flight(struct request_queue *q) 554 { 555 return q->in_flight[0] + q->in_flight[1]; 556 } 557 558 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 559 { 560 queue_lockdep_assert_held(q); 561 __clear_bit(flag, &q->queue_flags); 562 } 563 564 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 565 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 566 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags) 567 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 568 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags) 569 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags) 570 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 571 #define blk_queue_noxmerges(q) \ 572 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 573 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 574 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 575 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 576 #define blk_queue_stackable(q) \ 577 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 578 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 579 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \ 580 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags)) 581 582 #define blk_noretry_request(rq) \ 583 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 584 REQ_FAILFAST_DRIVER)) 585 586 #define blk_account_rq(rq) \ 587 (((rq)->cmd_flags & REQ_STARTED) && \ 588 ((rq)->cmd_type == REQ_TYPE_FS)) 589 590 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 591 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 592 /* rq->queuelist of dequeued request must be list_empty() */ 593 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 594 595 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 596 597 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1)) 598 599 /* 600 * Driver can handle struct request, if it either has an old style 601 * request_fn defined, or is blk-mq based. 602 */ 603 static inline bool queue_is_rq_based(struct request_queue *q) 604 { 605 return q->request_fn || q->mq_ops; 606 } 607 608 static inline unsigned int blk_queue_cluster(struct request_queue *q) 609 { 610 return q->limits.cluster; 611 } 612 613 /* 614 * We regard a request as sync, if either a read or a sync write 615 */ 616 static inline bool rw_is_sync(unsigned int rw_flags) 617 { 618 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC); 619 } 620 621 static inline bool rq_is_sync(struct request *rq) 622 { 623 return rw_is_sync(rq->cmd_flags); 624 } 625 626 static inline bool blk_rl_full(struct request_list *rl, bool sync) 627 { 628 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 629 630 return rl->flags & flag; 631 } 632 633 static inline void blk_set_rl_full(struct request_list *rl, bool sync) 634 { 635 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 636 637 rl->flags |= flag; 638 } 639 640 static inline void blk_clear_rl_full(struct request_list *rl, bool sync) 641 { 642 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 643 644 rl->flags &= ~flag; 645 } 646 647 static inline bool rq_mergeable(struct request *rq) 648 { 649 if (rq->cmd_type != REQ_TYPE_FS) 650 return false; 651 652 if (rq->cmd_flags & REQ_NOMERGE_FLAGS) 653 return false; 654 655 return true; 656 } 657 658 static inline bool blk_check_merge_flags(unsigned int flags1, 659 unsigned int flags2) 660 { 661 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD)) 662 return false; 663 664 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE)) 665 return false; 666 667 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME)) 668 return false; 669 670 return true; 671 } 672 673 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b) 674 { 675 if (bio_data(a) == bio_data(b)) 676 return true; 677 678 return false; 679 } 680 681 /* 682 * q->prep_rq_fn return values 683 */ 684 #define BLKPREP_OK 0 /* serve it */ 685 #define BLKPREP_KILL 1 /* fatal error, kill */ 686 #define BLKPREP_DEFER 2 /* leave on queue */ 687 688 extern unsigned long blk_max_low_pfn, blk_max_pfn; 689 690 /* 691 * standard bounce addresses: 692 * 693 * BLK_BOUNCE_HIGH : bounce all highmem pages 694 * BLK_BOUNCE_ANY : don't bounce anything 695 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 696 */ 697 698 #if BITS_PER_LONG == 32 699 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 700 #else 701 #define BLK_BOUNCE_HIGH -1ULL 702 #endif 703 #define BLK_BOUNCE_ANY (-1ULL) 704 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 705 706 /* 707 * default timeout for SG_IO if none specified 708 */ 709 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 710 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 711 712 #ifdef CONFIG_BOUNCE 713 extern int init_emergency_isa_pool(void); 714 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 715 #else 716 static inline int init_emergency_isa_pool(void) 717 { 718 return 0; 719 } 720 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 721 { 722 } 723 #endif /* CONFIG_MMU */ 724 725 struct rq_map_data { 726 struct page **pages; 727 int page_order; 728 int nr_entries; 729 unsigned long offset; 730 int null_mapped; 731 int from_user; 732 }; 733 734 struct req_iterator { 735 struct bvec_iter iter; 736 struct bio *bio; 737 }; 738 739 /* This should not be used directly - use rq_for_each_segment */ 740 #define for_each_bio(_bio) \ 741 for (; _bio; _bio = _bio->bi_next) 742 #define __rq_for_each_bio(_bio, rq) \ 743 if ((rq->bio)) \ 744 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 745 746 #define rq_for_each_segment(bvl, _rq, _iter) \ 747 __rq_for_each_bio(_iter.bio, _rq) \ 748 bio_for_each_segment(bvl, _iter.bio, _iter.iter) 749 750 #define rq_iter_last(bvec, _iter) \ 751 (_iter.bio->bi_next == NULL && \ 752 bio_iter_last(bvec, _iter.iter)) 753 754 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 755 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 756 #endif 757 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 758 extern void rq_flush_dcache_pages(struct request *rq); 759 #else 760 static inline void rq_flush_dcache_pages(struct request *rq) 761 { 762 } 763 #endif 764 765 extern int blk_register_queue(struct gendisk *disk); 766 extern void blk_unregister_queue(struct gendisk *disk); 767 extern blk_qc_t generic_make_request(struct bio *bio); 768 extern void blk_rq_init(struct request_queue *q, struct request *rq); 769 extern void blk_put_request(struct request *); 770 extern void __blk_put_request(struct request_queue *, struct request *); 771 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 772 extern struct request *blk_make_request(struct request_queue *, struct bio *, 773 gfp_t); 774 extern void blk_rq_set_block_pc(struct request *); 775 extern void blk_requeue_request(struct request_queue *, struct request *); 776 extern void blk_add_request_payload(struct request *rq, struct page *page, 777 unsigned int len); 778 extern int blk_lld_busy(struct request_queue *q); 779 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 780 struct bio_set *bs, gfp_t gfp_mask, 781 int (*bio_ctr)(struct bio *, struct bio *, void *), 782 void *data); 783 extern void blk_rq_unprep_clone(struct request *rq); 784 extern int blk_insert_cloned_request(struct request_queue *q, 785 struct request *rq); 786 extern void blk_delay_queue(struct request_queue *, unsigned long); 787 extern void blk_queue_split(struct request_queue *, struct bio **, 788 struct bio_set *); 789 extern void blk_recount_segments(struct request_queue *, struct bio *); 790 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 791 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 792 unsigned int, void __user *); 793 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 794 unsigned int, void __user *); 795 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 796 struct scsi_ioctl_command __user *); 797 798 extern int blk_queue_enter(struct request_queue *q, bool nowait); 799 extern void blk_queue_exit(struct request_queue *q); 800 extern void blk_start_queue(struct request_queue *q); 801 extern void blk_start_queue_async(struct request_queue *q); 802 extern void blk_stop_queue(struct request_queue *q); 803 extern void blk_sync_queue(struct request_queue *q); 804 extern void __blk_stop_queue(struct request_queue *q); 805 extern void __blk_run_queue(struct request_queue *q); 806 extern void __blk_run_queue_uncond(struct request_queue *q); 807 extern void blk_run_queue(struct request_queue *); 808 extern void blk_run_queue_async(struct request_queue *q); 809 extern int blk_rq_map_user(struct request_queue *, struct request *, 810 struct rq_map_data *, void __user *, unsigned long, 811 gfp_t); 812 extern int blk_rq_unmap_user(struct bio *); 813 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 814 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 815 struct rq_map_data *, const struct iov_iter *, 816 gfp_t); 817 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 818 struct request *, int); 819 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 820 struct request *, int, rq_end_io_fn *); 821 822 bool blk_poll(struct request_queue *q, blk_qc_t cookie); 823 824 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 825 { 826 return bdev->bd_disk->queue; /* this is never NULL */ 827 } 828 829 /* 830 * blk_rq_pos() : the current sector 831 * blk_rq_bytes() : bytes left in the entire request 832 * blk_rq_cur_bytes() : bytes left in the current segment 833 * blk_rq_err_bytes() : bytes left till the next error boundary 834 * blk_rq_sectors() : sectors left in the entire request 835 * blk_rq_cur_sectors() : sectors left in the current segment 836 */ 837 static inline sector_t blk_rq_pos(const struct request *rq) 838 { 839 return rq->__sector; 840 } 841 842 static inline unsigned int blk_rq_bytes(const struct request *rq) 843 { 844 return rq->__data_len; 845 } 846 847 static inline int blk_rq_cur_bytes(const struct request *rq) 848 { 849 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 850 } 851 852 extern unsigned int blk_rq_err_bytes(const struct request *rq); 853 854 static inline unsigned int blk_rq_sectors(const struct request *rq) 855 { 856 return blk_rq_bytes(rq) >> 9; 857 } 858 859 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 860 { 861 return blk_rq_cur_bytes(rq) >> 9; 862 } 863 864 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q, 865 unsigned int cmd_flags) 866 { 867 if (unlikely(cmd_flags & REQ_DISCARD)) 868 return min(q->limits.max_discard_sectors, UINT_MAX >> 9); 869 870 if (unlikely(cmd_flags & REQ_WRITE_SAME)) 871 return q->limits.max_write_same_sectors; 872 873 return q->limits.max_sectors; 874 } 875 876 /* 877 * Return maximum size of a request at given offset. Only valid for 878 * file system requests. 879 */ 880 static inline unsigned int blk_max_size_offset(struct request_queue *q, 881 sector_t offset) 882 { 883 if (!q->limits.chunk_sectors) 884 return q->limits.max_sectors; 885 886 return q->limits.chunk_sectors - 887 (offset & (q->limits.chunk_sectors - 1)); 888 } 889 890 static inline unsigned int blk_rq_get_max_sectors(struct request *rq) 891 { 892 struct request_queue *q = rq->q; 893 894 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC)) 895 return q->limits.max_hw_sectors; 896 897 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD)) 898 return blk_queue_get_max_sectors(q, rq->cmd_flags); 899 900 return min(blk_max_size_offset(q, blk_rq_pos(rq)), 901 blk_queue_get_max_sectors(q, rq->cmd_flags)); 902 } 903 904 static inline unsigned int blk_rq_count_bios(struct request *rq) 905 { 906 unsigned int nr_bios = 0; 907 struct bio *bio; 908 909 __rq_for_each_bio(bio, rq) 910 nr_bios++; 911 912 return nr_bios; 913 } 914 915 /* 916 * Request issue related functions. 917 */ 918 extern struct request *blk_peek_request(struct request_queue *q); 919 extern void blk_start_request(struct request *rq); 920 extern struct request *blk_fetch_request(struct request_queue *q); 921 922 /* 923 * Request completion related functions. 924 * 925 * blk_update_request() completes given number of bytes and updates 926 * the request without completing it. 927 * 928 * blk_end_request() and friends. __blk_end_request() must be called 929 * with the request queue spinlock acquired. 930 * 931 * Several drivers define their own end_request and call 932 * blk_end_request() for parts of the original function. 933 * This prevents code duplication in drivers. 934 */ 935 extern bool blk_update_request(struct request *rq, int error, 936 unsigned int nr_bytes); 937 extern void blk_finish_request(struct request *rq, int error); 938 extern bool blk_end_request(struct request *rq, int error, 939 unsigned int nr_bytes); 940 extern void blk_end_request_all(struct request *rq, int error); 941 extern bool blk_end_request_cur(struct request *rq, int error); 942 extern bool blk_end_request_err(struct request *rq, int error); 943 extern bool __blk_end_request(struct request *rq, int error, 944 unsigned int nr_bytes); 945 extern void __blk_end_request_all(struct request *rq, int error); 946 extern bool __blk_end_request_cur(struct request *rq, int error); 947 extern bool __blk_end_request_err(struct request *rq, int error); 948 949 extern void blk_complete_request(struct request *); 950 extern void __blk_complete_request(struct request *); 951 extern void blk_abort_request(struct request *); 952 extern void blk_unprep_request(struct request *); 953 954 /* 955 * Access functions for manipulating queue properties 956 */ 957 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 958 spinlock_t *lock, int node_id); 959 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 960 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 961 request_fn_proc *, spinlock_t *); 962 extern void blk_cleanup_queue(struct request_queue *); 963 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 964 extern void blk_queue_bounce_limit(struct request_queue *, u64); 965 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 966 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int); 967 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 968 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 969 extern void blk_queue_max_discard_sectors(struct request_queue *q, 970 unsigned int max_discard_sectors); 971 extern void blk_queue_max_write_same_sectors(struct request_queue *q, 972 unsigned int max_write_same_sectors); 973 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 974 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 975 extern void blk_queue_alignment_offset(struct request_queue *q, 976 unsigned int alignment); 977 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 978 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 979 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 980 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 981 extern void blk_set_default_limits(struct queue_limits *lim); 982 extern void blk_set_stacking_limits(struct queue_limits *lim); 983 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 984 sector_t offset); 985 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 986 sector_t offset); 987 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 988 sector_t offset); 989 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 990 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 991 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 992 extern int blk_queue_dma_drain(struct request_queue *q, 993 dma_drain_needed_fn *dma_drain_needed, 994 void *buf, unsigned int size); 995 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 996 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 997 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long); 998 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 999 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 1000 extern void blk_queue_dma_alignment(struct request_queue *, int); 1001 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 1002 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 1003 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 1004 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 1005 extern void blk_queue_flush(struct request_queue *q, unsigned int flush); 1006 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 1007 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 1008 1009 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 1010 extern void blk_dump_rq_flags(struct request *, char *); 1011 extern long nr_blockdev_pages(void); 1012 1013 bool __must_check blk_get_queue(struct request_queue *); 1014 struct request_queue *blk_alloc_queue(gfp_t); 1015 struct request_queue *blk_alloc_queue_node(gfp_t, int); 1016 extern void blk_put_queue(struct request_queue *); 1017 extern void blk_set_queue_dying(struct request_queue *); 1018 1019 /* 1020 * block layer runtime pm functions 1021 */ 1022 #ifdef CONFIG_PM 1023 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev); 1024 extern int blk_pre_runtime_suspend(struct request_queue *q); 1025 extern void blk_post_runtime_suspend(struct request_queue *q, int err); 1026 extern void blk_pre_runtime_resume(struct request_queue *q); 1027 extern void blk_post_runtime_resume(struct request_queue *q, int err); 1028 #else 1029 static inline void blk_pm_runtime_init(struct request_queue *q, 1030 struct device *dev) {} 1031 static inline int blk_pre_runtime_suspend(struct request_queue *q) 1032 { 1033 return -ENOSYS; 1034 } 1035 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {} 1036 static inline void blk_pre_runtime_resume(struct request_queue *q) {} 1037 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {} 1038 #endif 1039 1040 /* 1041 * blk_plug permits building a queue of related requests by holding the I/O 1042 * fragments for a short period. This allows merging of sequential requests 1043 * into single larger request. As the requests are moved from a per-task list to 1044 * the device's request_queue in a batch, this results in improved scalability 1045 * as the lock contention for request_queue lock is reduced. 1046 * 1047 * It is ok not to disable preemption when adding the request to the plug list 1048 * or when attempting a merge, because blk_schedule_flush_list() will only flush 1049 * the plug list when the task sleeps by itself. For details, please see 1050 * schedule() where blk_schedule_flush_plug() is called. 1051 */ 1052 struct blk_plug { 1053 struct list_head list; /* requests */ 1054 struct list_head mq_list; /* blk-mq requests */ 1055 struct list_head cb_list; /* md requires an unplug callback */ 1056 }; 1057 #define BLK_MAX_REQUEST_COUNT 16 1058 1059 struct blk_plug_cb; 1060 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool); 1061 struct blk_plug_cb { 1062 struct list_head list; 1063 blk_plug_cb_fn callback; 1064 void *data; 1065 }; 1066 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, 1067 void *data, int size); 1068 extern void blk_start_plug(struct blk_plug *); 1069 extern void blk_finish_plug(struct blk_plug *); 1070 extern void blk_flush_plug_list(struct blk_plug *, bool); 1071 1072 static inline void blk_flush_plug(struct task_struct *tsk) 1073 { 1074 struct blk_plug *plug = tsk->plug; 1075 1076 if (plug) 1077 blk_flush_plug_list(plug, false); 1078 } 1079 1080 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 1081 { 1082 struct blk_plug *plug = tsk->plug; 1083 1084 if (plug) 1085 blk_flush_plug_list(plug, true); 1086 } 1087 1088 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1089 { 1090 struct blk_plug *plug = tsk->plug; 1091 1092 return plug && 1093 (!list_empty(&plug->list) || 1094 !list_empty(&plug->mq_list) || 1095 !list_empty(&plug->cb_list)); 1096 } 1097 1098 /* 1099 * tag stuff 1100 */ 1101 extern int blk_queue_start_tag(struct request_queue *, struct request *); 1102 extern struct request *blk_queue_find_tag(struct request_queue *, int); 1103 extern void blk_queue_end_tag(struct request_queue *, struct request *); 1104 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int); 1105 extern void blk_queue_free_tags(struct request_queue *); 1106 extern int blk_queue_resize_tags(struct request_queue *, int); 1107 extern void blk_queue_invalidate_tags(struct request_queue *); 1108 extern struct blk_queue_tag *blk_init_tags(int, int); 1109 extern void blk_free_tags(struct blk_queue_tag *); 1110 1111 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 1112 int tag) 1113 { 1114 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 1115 return NULL; 1116 return bqt->tag_index[tag]; 1117 } 1118 1119 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */ 1120 1121 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 1122 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1123 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 1124 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, 1125 sector_t nr_sects, gfp_t gfp_mask, struct page *page); 1126 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1127 sector_t nr_sects, gfp_t gfp_mask, bool discard); 1128 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 1129 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 1130 { 1131 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 1132 nr_blocks << (sb->s_blocksize_bits - 9), 1133 gfp_mask, flags); 1134 } 1135 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 1136 sector_t nr_blocks, gfp_t gfp_mask) 1137 { 1138 return blkdev_issue_zeroout(sb->s_bdev, 1139 block << (sb->s_blocksize_bits - 9), 1140 nr_blocks << (sb->s_blocksize_bits - 9), 1141 gfp_mask, true); 1142 } 1143 1144 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 1145 1146 enum blk_default_limits { 1147 BLK_MAX_SEGMENTS = 128, 1148 BLK_SAFE_MAX_SECTORS = 255, 1149 BLK_DEF_MAX_SECTORS = 2560, 1150 BLK_MAX_SEGMENT_SIZE = 65536, 1151 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 1152 }; 1153 1154 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1155 1156 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 1157 { 1158 return q->limits.bounce_pfn; 1159 } 1160 1161 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1162 { 1163 return q->limits.seg_boundary_mask; 1164 } 1165 1166 static inline unsigned long queue_virt_boundary(struct request_queue *q) 1167 { 1168 return q->limits.virt_boundary_mask; 1169 } 1170 1171 static inline unsigned int queue_max_sectors(struct request_queue *q) 1172 { 1173 return q->limits.max_sectors; 1174 } 1175 1176 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1177 { 1178 return q->limits.max_hw_sectors; 1179 } 1180 1181 static inline unsigned short queue_max_segments(struct request_queue *q) 1182 { 1183 return q->limits.max_segments; 1184 } 1185 1186 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1187 { 1188 return q->limits.max_segment_size; 1189 } 1190 1191 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1192 { 1193 int retval = 512; 1194 1195 if (q && q->limits.logical_block_size) 1196 retval = q->limits.logical_block_size; 1197 1198 return retval; 1199 } 1200 1201 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1202 { 1203 return queue_logical_block_size(bdev_get_queue(bdev)); 1204 } 1205 1206 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1207 { 1208 return q->limits.physical_block_size; 1209 } 1210 1211 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1212 { 1213 return queue_physical_block_size(bdev_get_queue(bdev)); 1214 } 1215 1216 static inline unsigned int queue_io_min(struct request_queue *q) 1217 { 1218 return q->limits.io_min; 1219 } 1220 1221 static inline int bdev_io_min(struct block_device *bdev) 1222 { 1223 return queue_io_min(bdev_get_queue(bdev)); 1224 } 1225 1226 static inline unsigned int queue_io_opt(struct request_queue *q) 1227 { 1228 return q->limits.io_opt; 1229 } 1230 1231 static inline int bdev_io_opt(struct block_device *bdev) 1232 { 1233 return queue_io_opt(bdev_get_queue(bdev)); 1234 } 1235 1236 static inline int queue_alignment_offset(struct request_queue *q) 1237 { 1238 if (q->limits.misaligned) 1239 return -1; 1240 1241 return q->limits.alignment_offset; 1242 } 1243 1244 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1245 { 1246 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1247 unsigned int alignment = sector_div(sector, granularity >> 9) << 9; 1248 1249 return (granularity + lim->alignment_offset - alignment) % granularity; 1250 } 1251 1252 static inline int bdev_alignment_offset(struct block_device *bdev) 1253 { 1254 struct request_queue *q = bdev_get_queue(bdev); 1255 1256 if (q->limits.misaligned) 1257 return -1; 1258 1259 if (bdev != bdev->bd_contains) 1260 return bdev->bd_part->alignment_offset; 1261 1262 return q->limits.alignment_offset; 1263 } 1264 1265 static inline int queue_discard_alignment(struct request_queue *q) 1266 { 1267 if (q->limits.discard_misaligned) 1268 return -1; 1269 1270 return q->limits.discard_alignment; 1271 } 1272 1273 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1274 { 1275 unsigned int alignment, granularity, offset; 1276 1277 if (!lim->max_discard_sectors) 1278 return 0; 1279 1280 /* Why are these in bytes, not sectors? */ 1281 alignment = lim->discard_alignment >> 9; 1282 granularity = lim->discard_granularity >> 9; 1283 if (!granularity) 1284 return 0; 1285 1286 /* Offset of the partition start in 'granularity' sectors */ 1287 offset = sector_div(sector, granularity); 1288 1289 /* And why do we do this modulus *again* in blkdev_issue_discard()? */ 1290 offset = (granularity + alignment - offset) % granularity; 1291 1292 /* Turn it back into bytes, gaah */ 1293 return offset << 9; 1294 } 1295 1296 static inline int bdev_discard_alignment(struct block_device *bdev) 1297 { 1298 struct request_queue *q = bdev_get_queue(bdev); 1299 1300 if (bdev != bdev->bd_contains) 1301 return bdev->bd_part->discard_alignment; 1302 1303 return q->limits.discard_alignment; 1304 } 1305 1306 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1307 { 1308 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) 1309 return 1; 1310 1311 return 0; 1312 } 1313 1314 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1315 { 1316 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1317 } 1318 1319 static inline unsigned int bdev_write_same(struct block_device *bdev) 1320 { 1321 struct request_queue *q = bdev_get_queue(bdev); 1322 1323 if (q) 1324 return q->limits.max_write_same_sectors; 1325 1326 return 0; 1327 } 1328 1329 static inline int queue_dma_alignment(struct request_queue *q) 1330 { 1331 return q ? q->dma_alignment : 511; 1332 } 1333 1334 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1335 unsigned int len) 1336 { 1337 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1338 return !(addr & alignment) && !(len & alignment); 1339 } 1340 1341 /* assumes size > 256 */ 1342 static inline unsigned int blksize_bits(unsigned int size) 1343 { 1344 unsigned int bits = 8; 1345 do { 1346 bits++; 1347 size >>= 1; 1348 } while (size > 256); 1349 return bits; 1350 } 1351 1352 static inline unsigned int block_size(struct block_device *bdev) 1353 { 1354 return bdev->bd_block_size; 1355 } 1356 1357 static inline bool queue_flush_queueable(struct request_queue *q) 1358 { 1359 return !q->flush_not_queueable; 1360 } 1361 1362 typedef struct {struct page *v;} Sector; 1363 1364 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1365 1366 static inline void put_dev_sector(Sector p) 1367 { 1368 page_cache_release(p.v); 1369 } 1370 1371 /* 1372 * Check if adding a bio_vec after bprv with offset would create a gap in 1373 * the SG list. Most drivers don't care about this, but some do. 1374 */ 1375 static inline bool bvec_gap_to_prev(struct request_queue *q, 1376 struct bio_vec *bprv, unsigned int offset) 1377 { 1378 if (!queue_virt_boundary(q)) 1379 return false; 1380 return offset || 1381 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); 1382 } 1383 1384 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev, 1385 struct bio *next) 1386 { 1387 if (!bio_has_data(prev)) 1388 return false; 1389 1390 return bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1], 1391 next->bi_io_vec[0].bv_offset); 1392 } 1393 1394 static inline bool req_gap_back_merge(struct request *req, struct bio *bio) 1395 { 1396 return bio_will_gap(req->q, req->biotail, bio); 1397 } 1398 1399 static inline bool req_gap_front_merge(struct request *req, struct bio *bio) 1400 { 1401 return bio_will_gap(req->q, bio, req->bio); 1402 } 1403 1404 struct work_struct; 1405 int kblockd_schedule_work(struct work_struct *work); 1406 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay); 1407 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay); 1408 1409 #ifdef CONFIG_BLK_CGROUP 1410 /* 1411 * This should not be using sched_clock(). A real patch is in progress 1412 * to fix this up, until that is in place we need to disable preemption 1413 * around sched_clock() in this function and set_io_start_time_ns(). 1414 */ 1415 static inline void set_start_time_ns(struct request *req) 1416 { 1417 preempt_disable(); 1418 req->start_time_ns = sched_clock(); 1419 preempt_enable(); 1420 } 1421 1422 static inline void set_io_start_time_ns(struct request *req) 1423 { 1424 preempt_disable(); 1425 req->io_start_time_ns = sched_clock(); 1426 preempt_enable(); 1427 } 1428 1429 static inline uint64_t rq_start_time_ns(struct request *req) 1430 { 1431 return req->start_time_ns; 1432 } 1433 1434 static inline uint64_t rq_io_start_time_ns(struct request *req) 1435 { 1436 return req->io_start_time_ns; 1437 } 1438 #else 1439 static inline void set_start_time_ns(struct request *req) {} 1440 static inline void set_io_start_time_ns(struct request *req) {} 1441 static inline uint64_t rq_start_time_ns(struct request *req) 1442 { 1443 return 0; 1444 } 1445 static inline uint64_t rq_io_start_time_ns(struct request *req) 1446 { 1447 return 0; 1448 } 1449 #endif 1450 1451 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1452 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1453 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1454 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1455 1456 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1457 1458 enum blk_integrity_flags { 1459 BLK_INTEGRITY_VERIFY = 1 << 0, 1460 BLK_INTEGRITY_GENERATE = 1 << 1, 1461 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2, 1462 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3, 1463 }; 1464 1465 struct blk_integrity_iter { 1466 void *prot_buf; 1467 void *data_buf; 1468 sector_t seed; 1469 unsigned int data_size; 1470 unsigned short interval; 1471 const char *disk_name; 1472 }; 1473 1474 typedef int (integrity_processing_fn) (struct blk_integrity_iter *); 1475 1476 struct blk_integrity_profile { 1477 integrity_processing_fn *generate_fn; 1478 integrity_processing_fn *verify_fn; 1479 const char *name; 1480 }; 1481 1482 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *); 1483 extern void blk_integrity_unregister(struct gendisk *); 1484 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1485 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1486 struct scatterlist *); 1487 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1488 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, 1489 struct request *); 1490 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, 1491 struct bio *); 1492 1493 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1494 { 1495 struct blk_integrity *bi = &disk->queue->integrity; 1496 1497 if (!bi->profile) 1498 return NULL; 1499 1500 return bi; 1501 } 1502 1503 static inline 1504 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1505 { 1506 return blk_get_integrity(bdev->bd_disk); 1507 } 1508 1509 static inline bool blk_integrity_rq(struct request *rq) 1510 { 1511 return rq->cmd_flags & REQ_INTEGRITY; 1512 } 1513 1514 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1515 unsigned int segs) 1516 { 1517 q->limits.max_integrity_segments = segs; 1518 } 1519 1520 static inline unsigned short 1521 queue_max_integrity_segments(struct request_queue *q) 1522 { 1523 return q->limits.max_integrity_segments; 1524 } 1525 1526 static inline bool integrity_req_gap_back_merge(struct request *req, 1527 struct bio *next) 1528 { 1529 struct bio_integrity_payload *bip = bio_integrity(req->bio); 1530 struct bio_integrity_payload *bip_next = bio_integrity(next); 1531 1532 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1533 bip_next->bip_vec[0].bv_offset); 1534 } 1535 1536 static inline bool integrity_req_gap_front_merge(struct request *req, 1537 struct bio *bio) 1538 { 1539 struct bio_integrity_payload *bip = bio_integrity(bio); 1540 struct bio_integrity_payload *bip_next = bio_integrity(req->bio); 1541 1542 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1543 bip_next->bip_vec[0].bv_offset); 1544 } 1545 1546 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1547 1548 struct bio; 1549 struct block_device; 1550 struct gendisk; 1551 struct blk_integrity; 1552 1553 static inline int blk_integrity_rq(struct request *rq) 1554 { 1555 return 0; 1556 } 1557 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1558 struct bio *b) 1559 { 1560 return 0; 1561 } 1562 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1563 struct bio *b, 1564 struct scatterlist *s) 1565 { 1566 return 0; 1567 } 1568 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1569 { 1570 return NULL; 1571 } 1572 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1573 { 1574 return NULL; 1575 } 1576 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1577 { 1578 return 0; 1579 } 1580 static inline void blk_integrity_register(struct gendisk *d, 1581 struct blk_integrity *b) 1582 { 1583 } 1584 static inline void blk_integrity_unregister(struct gendisk *d) 1585 { 1586 } 1587 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1588 unsigned int segs) 1589 { 1590 } 1591 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1592 { 1593 return 0; 1594 } 1595 static inline bool blk_integrity_merge_rq(struct request_queue *rq, 1596 struct request *r1, 1597 struct request *r2) 1598 { 1599 return true; 1600 } 1601 static inline bool blk_integrity_merge_bio(struct request_queue *rq, 1602 struct request *r, 1603 struct bio *b) 1604 { 1605 return true; 1606 } 1607 1608 static inline bool integrity_req_gap_back_merge(struct request *req, 1609 struct bio *next) 1610 { 1611 return false; 1612 } 1613 static inline bool integrity_req_gap_front_merge(struct request *req, 1614 struct bio *bio) 1615 { 1616 return false; 1617 } 1618 1619 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1620 1621 /** 1622 * struct blk_dax_ctl - control and output parameters for ->direct_access 1623 * @sector: (input) offset relative to a block_device 1624 * @addr: (output) kernel virtual address for @sector populated by driver 1625 * @pfn: (output) page frame number for @addr populated by driver 1626 * @size: (input) number of bytes requested 1627 */ 1628 struct blk_dax_ctl { 1629 sector_t sector; 1630 void __pmem *addr; 1631 long size; 1632 pfn_t pfn; 1633 }; 1634 1635 struct block_device_operations { 1636 int (*open) (struct block_device *, fmode_t); 1637 void (*release) (struct gendisk *, fmode_t); 1638 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw); 1639 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1640 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1641 long (*direct_access)(struct block_device *, sector_t, void __pmem **, 1642 pfn_t *); 1643 unsigned int (*check_events) (struct gendisk *disk, 1644 unsigned int clearing); 1645 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1646 int (*media_changed) (struct gendisk *); 1647 void (*unlock_native_capacity) (struct gendisk *); 1648 int (*revalidate_disk) (struct gendisk *); 1649 int (*getgeo)(struct block_device *, struct hd_geometry *); 1650 /* this callback is with swap_lock and sometimes page table lock held */ 1651 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1652 struct module *owner; 1653 const struct pr_ops *pr_ops; 1654 }; 1655 1656 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1657 unsigned long); 1658 extern int bdev_read_page(struct block_device *, sector_t, struct page *); 1659 extern int bdev_write_page(struct block_device *, sector_t, struct page *, 1660 struct writeback_control *); 1661 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *); 1662 #else /* CONFIG_BLOCK */ 1663 1664 struct block_device; 1665 1666 /* 1667 * stubs for when the block layer is configured out 1668 */ 1669 #define buffer_heads_over_limit 0 1670 1671 static inline long nr_blockdev_pages(void) 1672 { 1673 return 0; 1674 } 1675 1676 struct blk_plug { 1677 }; 1678 1679 static inline void blk_start_plug(struct blk_plug *plug) 1680 { 1681 } 1682 1683 static inline void blk_finish_plug(struct blk_plug *plug) 1684 { 1685 } 1686 1687 static inline void blk_flush_plug(struct task_struct *task) 1688 { 1689 } 1690 1691 static inline void blk_schedule_flush_plug(struct task_struct *task) 1692 { 1693 } 1694 1695 1696 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1697 { 1698 return false; 1699 } 1700 1701 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, 1702 sector_t *error_sector) 1703 { 1704 return 0; 1705 } 1706 1707 #endif /* CONFIG_BLOCK */ 1708 1709 #endif 1710