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