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 work_struct timeout_work; 413 struct list_head timeout_list; 414 415 struct list_head icq_list; 416 #ifdef CONFIG_BLK_CGROUP 417 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); 418 struct blkcg_gq *root_blkg; 419 struct list_head blkg_list; 420 #endif 421 422 struct queue_limits limits; 423 424 /* 425 * sg stuff 426 */ 427 unsigned int sg_timeout; 428 unsigned int sg_reserved_size; 429 int node; 430 #ifdef CONFIG_BLK_DEV_IO_TRACE 431 struct blk_trace *blk_trace; 432 #endif 433 /* 434 * for flush operations 435 */ 436 unsigned int flush_flags; 437 unsigned int flush_not_queueable:1; 438 struct blk_flush_queue *fq; 439 440 struct list_head requeue_list; 441 spinlock_t requeue_lock; 442 struct work_struct requeue_work; 443 444 struct mutex sysfs_lock; 445 446 int bypass_depth; 447 atomic_t mq_freeze_depth; 448 449 #if defined(CONFIG_BLK_DEV_BSG) 450 bsg_job_fn *bsg_job_fn; 451 int bsg_job_size; 452 struct bsg_class_device bsg_dev; 453 #endif 454 455 #ifdef CONFIG_BLK_DEV_THROTTLING 456 /* Throttle data */ 457 struct throtl_data *td; 458 #endif 459 struct rcu_head rcu_head; 460 wait_queue_head_t mq_freeze_wq; 461 struct percpu_ref q_usage_counter; 462 struct list_head all_q_node; 463 464 struct blk_mq_tag_set *tag_set; 465 struct list_head tag_set_list; 466 struct bio_set *bio_split; 467 468 bool mq_sysfs_init_done; 469 }; 470 471 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 472 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 473 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 474 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 475 #define QUEUE_FLAG_DYING 5 /* queue being torn down */ 476 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */ 477 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ 478 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ 479 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ 480 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ 481 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ 482 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ 483 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 484 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ 485 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ 486 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ 487 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ 488 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */ 489 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ 490 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */ 491 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */ 492 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/ 493 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */ 494 495 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 496 (1 << QUEUE_FLAG_STACKABLE) | \ 497 (1 << QUEUE_FLAG_SAME_COMP) | \ 498 (1 << QUEUE_FLAG_ADD_RANDOM)) 499 500 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 501 (1 << QUEUE_FLAG_STACKABLE) | \ 502 (1 << QUEUE_FLAG_SAME_COMP)) 503 504 static inline void queue_lockdep_assert_held(struct request_queue *q) 505 { 506 if (q->queue_lock) 507 lockdep_assert_held(q->queue_lock); 508 } 509 510 static inline void queue_flag_set_unlocked(unsigned int flag, 511 struct request_queue *q) 512 { 513 __set_bit(flag, &q->queue_flags); 514 } 515 516 static inline int queue_flag_test_and_clear(unsigned int flag, 517 struct request_queue *q) 518 { 519 queue_lockdep_assert_held(q); 520 521 if (test_bit(flag, &q->queue_flags)) { 522 __clear_bit(flag, &q->queue_flags); 523 return 1; 524 } 525 526 return 0; 527 } 528 529 static inline int queue_flag_test_and_set(unsigned int flag, 530 struct request_queue *q) 531 { 532 queue_lockdep_assert_held(q); 533 534 if (!test_bit(flag, &q->queue_flags)) { 535 __set_bit(flag, &q->queue_flags); 536 return 0; 537 } 538 539 return 1; 540 } 541 542 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 543 { 544 queue_lockdep_assert_held(q); 545 __set_bit(flag, &q->queue_flags); 546 } 547 548 static inline void queue_flag_clear_unlocked(unsigned int flag, 549 struct request_queue *q) 550 { 551 __clear_bit(flag, &q->queue_flags); 552 } 553 554 static inline int queue_in_flight(struct request_queue *q) 555 { 556 return q->in_flight[0] + q->in_flight[1]; 557 } 558 559 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 560 { 561 queue_lockdep_assert_held(q); 562 __clear_bit(flag, &q->queue_flags); 563 } 564 565 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 566 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 567 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags) 568 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 569 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags) 570 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags) 571 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 572 #define blk_queue_noxmerges(q) \ 573 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 574 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 575 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 576 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 577 #define blk_queue_stackable(q) \ 578 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 579 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 580 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \ 581 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags)) 582 583 #define blk_noretry_request(rq) \ 584 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 585 REQ_FAILFAST_DRIVER)) 586 587 #define blk_account_rq(rq) \ 588 (((rq)->cmd_flags & REQ_STARTED) && \ 589 ((rq)->cmd_type == REQ_TYPE_FS)) 590 591 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 592 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 593 /* rq->queuelist of dequeued request must be list_empty() */ 594 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 595 596 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 597 598 #define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1)) 599 600 /* 601 * Driver can handle struct request, if it either has an old style 602 * request_fn defined, or is blk-mq based. 603 */ 604 static inline bool queue_is_rq_based(struct request_queue *q) 605 { 606 return q->request_fn || q->mq_ops; 607 } 608 609 static inline unsigned int blk_queue_cluster(struct request_queue *q) 610 { 611 return q->limits.cluster; 612 } 613 614 /* 615 * We regard a request as sync, if either a read or a sync write 616 */ 617 static inline bool rw_is_sync(unsigned int rw_flags) 618 { 619 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC); 620 } 621 622 static inline bool rq_is_sync(struct request *rq) 623 { 624 return rw_is_sync(rq->cmd_flags); 625 } 626 627 static inline bool blk_rl_full(struct request_list *rl, bool sync) 628 { 629 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 630 631 return rl->flags & flag; 632 } 633 634 static inline void blk_set_rl_full(struct request_list *rl, bool sync) 635 { 636 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 637 638 rl->flags |= flag; 639 } 640 641 static inline void blk_clear_rl_full(struct request_list *rl, bool sync) 642 { 643 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 644 645 rl->flags &= ~flag; 646 } 647 648 static inline bool rq_mergeable(struct request *rq) 649 { 650 if (rq->cmd_type != REQ_TYPE_FS) 651 return false; 652 653 if (rq->cmd_flags & REQ_NOMERGE_FLAGS) 654 return false; 655 656 return true; 657 } 658 659 static inline bool blk_check_merge_flags(unsigned int flags1, 660 unsigned int flags2) 661 { 662 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD)) 663 return false; 664 665 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE)) 666 return false; 667 668 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME)) 669 return false; 670 671 return true; 672 } 673 674 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b) 675 { 676 if (bio_data(a) == bio_data(b)) 677 return true; 678 679 return false; 680 } 681 682 /* 683 * q->prep_rq_fn return values 684 */ 685 enum { 686 BLKPREP_OK, /* serve it */ 687 BLKPREP_KILL, /* fatal error, kill, return -EIO */ 688 BLKPREP_DEFER, /* leave on queue */ 689 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */ 690 }; 691 692 extern unsigned long blk_max_low_pfn, blk_max_pfn; 693 694 /* 695 * standard bounce addresses: 696 * 697 * BLK_BOUNCE_HIGH : bounce all highmem pages 698 * BLK_BOUNCE_ANY : don't bounce anything 699 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 700 */ 701 702 #if BITS_PER_LONG == 32 703 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 704 #else 705 #define BLK_BOUNCE_HIGH -1ULL 706 #endif 707 #define BLK_BOUNCE_ANY (-1ULL) 708 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 709 710 /* 711 * default timeout for SG_IO if none specified 712 */ 713 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 714 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 715 716 #ifdef CONFIG_BOUNCE 717 extern int init_emergency_isa_pool(void); 718 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 719 #else 720 static inline int init_emergency_isa_pool(void) 721 { 722 return 0; 723 } 724 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 725 { 726 } 727 #endif /* CONFIG_MMU */ 728 729 struct rq_map_data { 730 struct page **pages; 731 int page_order; 732 int nr_entries; 733 unsigned long offset; 734 int null_mapped; 735 int from_user; 736 }; 737 738 struct req_iterator { 739 struct bvec_iter iter; 740 struct bio *bio; 741 }; 742 743 /* This should not be used directly - use rq_for_each_segment */ 744 #define for_each_bio(_bio) \ 745 for (; _bio; _bio = _bio->bi_next) 746 #define __rq_for_each_bio(_bio, rq) \ 747 if ((rq->bio)) \ 748 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 749 750 #define rq_for_each_segment(bvl, _rq, _iter) \ 751 __rq_for_each_bio(_iter.bio, _rq) \ 752 bio_for_each_segment(bvl, _iter.bio, _iter.iter) 753 754 #define rq_iter_last(bvec, _iter) \ 755 (_iter.bio->bi_next == NULL && \ 756 bio_iter_last(bvec, _iter.iter)) 757 758 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 759 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 760 #endif 761 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 762 extern void rq_flush_dcache_pages(struct request *rq); 763 #else 764 static inline void rq_flush_dcache_pages(struct request *rq) 765 { 766 } 767 #endif 768 769 extern int blk_register_queue(struct gendisk *disk); 770 extern void blk_unregister_queue(struct gendisk *disk); 771 extern blk_qc_t generic_make_request(struct bio *bio); 772 extern void blk_rq_init(struct request_queue *q, struct request *rq); 773 extern void blk_put_request(struct request *); 774 extern void __blk_put_request(struct request_queue *, struct request *); 775 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 776 extern struct request *blk_make_request(struct request_queue *, struct bio *, 777 gfp_t); 778 extern void blk_rq_set_block_pc(struct request *); 779 extern void blk_requeue_request(struct request_queue *, struct request *); 780 extern void blk_add_request_payload(struct request *rq, struct page *page, 781 unsigned int len); 782 extern int blk_lld_busy(struct request_queue *q); 783 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 784 struct bio_set *bs, gfp_t gfp_mask, 785 int (*bio_ctr)(struct bio *, struct bio *, void *), 786 void *data); 787 extern void blk_rq_unprep_clone(struct request *rq); 788 extern int blk_insert_cloned_request(struct request_queue *q, 789 struct request *rq); 790 extern void blk_delay_queue(struct request_queue *, unsigned long); 791 extern void blk_queue_split(struct request_queue *, struct bio **, 792 struct bio_set *); 793 extern void blk_recount_segments(struct request_queue *, struct bio *); 794 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 795 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 796 unsigned int, void __user *); 797 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 798 unsigned int, void __user *); 799 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 800 struct scsi_ioctl_command __user *); 801 802 extern int blk_queue_enter(struct request_queue *q, bool nowait); 803 extern void blk_queue_exit(struct request_queue *q); 804 extern void blk_start_queue(struct request_queue *q); 805 extern void blk_start_queue_async(struct request_queue *q); 806 extern void blk_stop_queue(struct request_queue *q); 807 extern void blk_sync_queue(struct request_queue *q); 808 extern void __blk_stop_queue(struct request_queue *q); 809 extern void __blk_run_queue(struct request_queue *q); 810 extern void __blk_run_queue_uncond(struct request_queue *q); 811 extern void blk_run_queue(struct request_queue *); 812 extern void blk_run_queue_async(struct request_queue *q); 813 extern int blk_rq_map_user(struct request_queue *, struct request *, 814 struct rq_map_data *, void __user *, unsigned long, 815 gfp_t); 816 extern int blk_rq_unmap_user(struct bio *); 817 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 818 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 819 struct rq_map_data *, const struct iov_iter *, 820 gfp_t); 821 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 822 struct request *, int); 823 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 824 struct request *, int, rq_end_io_fn *); 825 826 bool blk_poll(struct request_queue *q, blk_qc_t cookie); 827 828 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 829 { 830 return bdev->bd_disk->queue; /* this is never NULL */ 831 } 832 833 /* 834 * blk_rq_pos() : the current sector 835 * blk_rq_bytes() : bytes left in the entire request 836 * blk_rq_cur_bytes() : bytes left in the current segment 837 * blk_rq_err_bytes() : bytes left till the next error boundary 838 * blk_rq_sectors() : sectors left in the entire request 839 * blk_rq_cur_sectors() : sectors left in the current segment 840 */ 841 static inline sector_t blk_rq_pos(const struct request *rq) 842 { 843 return rq->__sector; 844 } 845 846 static inline unsigned int blk_rq_bytes(const struct request *rq) 847 { 848 return rq->__data_len; 849 } 850 851 static inline int blk_rq_cur_bytes(const struct request *rq) 852 { 853 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 854 } 855 856 extern unsigned int blk_rq_err_bytes(const struct request *rq); 857 858 static inline unsigned int blk_rq_sectors(const struct request *rq) 859 { 860 return blk_rq_bytes(rq) >> 9; 861 } 862 863 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 864 { 865 return blk_rq_cur_bytes(rq) >> 9; 866 } 867 868 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q, 869 unsigned int cmd_flags) 870 { 871 if (unlikely(cmd_flags & REQ_DISCARD)) 872 return min(q->limits.max_discard_sectors, UINT_MAX >> 9); 873 874 if (unlikely(cmd_flags & REQ_WRITE_SAME)) 875 return q->limits.max_write_same_sectors; 876 877 return q->limits.max_sectors; 878 } 879 880 /* 881 * Return maximum size of a request at given offset. Only valid for 882 * file system requests. 883 */ 884 static inline unsigned int blk_max_size_offset(struct request_queue *q, 885 sector_t offset) 886 { 887 if (!q->limits.chunk_sectors) 888 return q->limits.max_sectors; 889 890 return q->limits.chunk_sectors - 891 (offset & (q->limits.chunk_sectors - 1)); 892 } 893 894 static inline unsigned int blk_rq_get_max_sectors(struct request *rq) 895 { 896 struct request_queue *q = rq->q; 897 898 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC)) 899 return q->limits.max_hw_sectors; 900 901 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD)) 902 return blk_queue_get_max_sectors(q, rq->cmd_flags); 903 904 return min(blk_max_size_offset(q, blk_rq_pos(rq)), 905 blk_queue_get_max_sectors(q, rq->cmd_flags)); 906 } 907 908 static inline unsigned int blk_rq_count_bios(struct request *rq) 909 { 910 unsigned int nr_bios = 0; 911 struct bio *bio; 912 913 __rq_for_each_bio(bio, rq) 914 nr_bios++; 915 916 return nr_bios; 917 } 918 919 /* 920 * Request issue related functions. 921 */ 922 extern struct request *blk_peek_request(struct request_queue *q); 923 extern void blk_start_request(struct request *rq); 924 extern struct request *blk_fetch_request(struct request_queue *q); 925 926 /* 927 * Request completion related functions. 928 * 929 * blk_update_request() completes given number of bytes and updates 930 * the request without completing it. 931 * 932 * blk_end_request() and friends. __blk_end_request() must be called 933 * with the request queue spinlock acquired. 934 * 935 * Several drivers define their own end_request and call 936 * blk_end_request() for parts of the original function. 937 * This prevents code duplication in drivers. 938 */ 939 extern bool blk_update_request(struct request *rq, int error, 940 unsigned int nr_bytes); 941 extern void blk_finish_request(struct request *rq, int error); 942 extern bool blk_end_request(struct request *rq, int error, 943 unsigned int nr_bytes); 944 extern void blk_end_request_all(struct request *rq, int error); 945 extern bool blk_end_request_cur(struct request *rq, int error); 946 extern bool blk_end_request_err(struct request *rq, int error); 947 extern bool __blk_end_request(struct request *rq, int error, 948 unsigned int nr_bytes); 949 extern void __blk_end_request_all(struct request *rq, int error); 950 extern bool __blk_end_request_cur(struct request *rq, int error); 951 extern bool __blk_end_request_err(struct request *rq, int error); 952 953 extern void blk_complete_request(struct request *); 954 extern void __blk_complete_request(struct request *); 955 extern void blk_abort_request(struct request *); 956 extern void blk_unprep_request(struct request *); 957 958 /* 959 * Access functions for manipulating queue properties 960 */ 961 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 962 spinlock_t *lock, int node_id); 963 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 964 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 965 request_fn_proc *, spinlock_t *); 966 extern void blk_cleanup_queue(struct request_queue *); 967 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 968 extern void blk_queue_bounce_limit(struct request_queue *, u64); 969 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 970 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int); 971 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 972 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 973 extern void blk_queue_max_discard_sectors(struct request_queue *q, 974 unsigned int max_discard_sectors); 975 extern void blk_queue_max_write_same_sectors(struct request_queue *q, 976 unsigned int max_write_same_sectors); 977 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 978 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 979 extern void blk_queue_alignment_offset(struct request_queue *q, 980 unsigned int alignment); 981 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 982 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 983 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 984 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 985 extern void blk_set_default_limits(struct queue_limits *lim); 986 extern void blk_set_stacking_limits(struct queue_limits *lim); 987 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 988 sector_t offset); 989 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 990 sector_t offset); 991 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 992 sector_t offset); 993 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 994 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 995 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 996 extern int blk_queue_dma_drain(struct request_queue *q, 997 dma_drain_needed_fn *dma_drain_needed, 998 void *buf, unsigned int size); 999 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 1000 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 1001 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long); 1002 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 1003 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 1004 extern void blk_queue_dma_alignment(struct request_queue *, int); 1005 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 1006 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 1007 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 1008 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 1009 extern void blk_queue_flush(struct request_queue *q, unsigned int flush); 1010 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 1011 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 1012 1013 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 1014 extern void blk_dump_rq_flags(struct request *, char *); 1015 extern long nr_blockdev_pages(void); 1016 1017 bool __must_check blk_get_queue(struct request_queue *); 1018 struct request_queue *blk_alloc_queue(gfp_t); 1019 struct request_queue *blk_alloc_queue_node(gfp_t, int); 1020 extern void blk_put_queue(struct request_queue *); 1021 extern void blk_set_queue_dying(struct request_queue *); 1022 1023 /* 1024 * block layer runtime pm functions 1025 */ 1026 #ifdef CONFIG_PM 1027 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev); 1028 extern int blk_pre_runtime_suspend(struct request_queue *q); 1029 extern void blk_post_runtime_suspend(struct request_queue *q, int err); 1030 extern void blk_pre_runtime_resume(struct request_queue *q); 1031 extern void blk_post_runtime_resume(struct request_queue *q, int err); 1032 #else 1033 static inline void blk_pm_runtime_init(struct request_queue *q, 1034 struct device *dev) {} 1035 static inline int blk_pre_runtime_suspend(struct request_queue *q) 1036 { 1037 return -ENOSYS; 1038 } 1039 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {} 1040 static inline void blk_pre_runtime_resume(struct request_queue *q) {} 1041 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {} 1042 #endif 1043 1044 /* 1045 * blk_plug permits building a queue of related requests by holding the I/O 1046 * fragments for a short period. This allows merging of sequential requests 1047 * into single larger request. As the requests are moved from a per-task list to 1048 * the device's request_queue in a batch, this results in improved scalability 1049 * as the lock contention for request_queue lock is reduced. 1050 * 1051 * It is ok not to disable preemption when adding the request to the plug list 1052 * or when attempting a merge, because blk_schedule_flush_list() will only flush 1053 * the plug list when the task sleeps by itself. For details, please see 1054 * schedule() where blk_schedule_flush_plug() is called. 1055 */ 1056 struct blk_plug { 1057 struct list_head list; /* requests */ 1058 struct list_head mq_list; /* blk-mq requests */ 1059 struct list_head cb_list; /* md requires an unplug callback */ 1060 }; 1061 #define BLK_MAX_REQUEST_COUNT 16 1062 1063 struct blk_plug_cb; 1064 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool); 1065 struct blk_plug_cb { 1066 struct list_head list; 1067 blk_plug_cb_fn callback; 1068 void *data; 1069 }; 1070 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, 1071 void *data, int size); 1072 extern void blk_start_plug(struct blk_plug *); 1073 extern void blk_finish_plug(struct blk_plug *); 1074 extern void blk_flush_plug_list(struct blk_plug *, bool); 1075 1076 static inline void blk_flush_plug(struct task_struct *tsk) 1077 { 1078 struct blk_plug *plug = tsk->plug; 1079 1080 if (plug) 1081 blk_flush_plug_list(plug, false); 1082 } 1083 1084 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 1085 { 1086 struct blk_plug *plug = tsk->plug; 1087 1088 if (plug) 1089 blk_flush_plug_list(plug, true); 1090 } 1091 1092 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1093 { 1094 struct blk_plug *plug = tsk->plug; 1095 1096 return plug && 1097 (!list_empty(&plug->list) || 1098 !list_empty(&plug->mq_list) || 1099 !list_empty(&plug->cb_list)); 1100 } 1101 1102 /* 1103 * tag stuff 1104 */ 1105 extern int blk_queue_start_tag(struct request_queue *, struct request *); 1106 extern struct request *blk_queue_find_tag(struct request_queue *, int); 1107 extern void blk_queue_end_tag(struct request_queue *, struct request *); 1108 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int); 1109 extern void blk_queue_free_tags(struct request_queue *); 1110 extern int blk_queue_resize_tags(struct request_queue *, int); 1111 extern void blk_queue_invalidate_tags(struct request_queue *); 1112 extern struct blk_queue_tag *blk_init_tags(int, int); 1113 extern void blk_free_tags(struct blk_queue_tag *); 1114 1115 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 1116 int tag) 1117 { 1118 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 1119 return NULL; 1120 return bqt->tag_index[tag]; 1121 } 1122 1123 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */ 1124 1125 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 1126 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1127 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 1128 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, 1129 sector_t nr_sects, gfp_t gfp_mask, struct page *page); 1130 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1131 sector_t nr_sects, gfp_t gfp_mask, bool discard); 1132 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 1133 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 1134 { 1135 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 1136 nr_blocks << (sb->s_blocksize_bits - 9), 1137 gfp_mask, flags); 1138 } 1139 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 1140 sector_t nr_blocks, gfp_t gfp_mask) 1141 { 1142 return blkdev_issue_zeroout(sb->s_bdev, 1143 block << (sb->s_blocksize_bits - 9), 1144 nr_blocks << (sb->s_blocksize_bits - 9), 1145 gfp_mask, true); 1146 } 1147 1148 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 1149 1150 enum blk_default_limits { 1151 BLK_MAX_SEGMENTS = 128, 1152 BLK_SAFE_MAX_SECTORS = 255, 1153 BLK_DEF_MAX_SECTORS = 2560, 1154 BLK_MAX_SEGMENT_SIZE = 65536, 1155 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 1156 }; 1157 1158 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1159 1160 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 1161 { 1162 return q->limits.bounce_pfn; 1163 } 1164 1165 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1166 { 1167 return q->limits.seg_boundary_mask; 1168 } 1169 1170 static inline unsigned long queue_virt_boundary(struct request_queue *q) 1171 { 1172 return q->limits.virt_boundary_mask; 1173 } 1174 1175 static inline unsigned int queue_max_sectors(struct request_queue *q) 1176 { 1177 return q->limits.max_sectors; 1178 } 1179 1180 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1181 { 1182 return q->limits.max_hw_sectors; 1183 } 1184 1185 static inline unsigned short queue_max_segments(struct request_queue *q) 1186 { 1187 return q->limits.max_segments; 1188 } 1189 1190 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1191 { 1192 return q->limits.max_segment_size; 1193 } 1194 1195 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1196 { 1197 int retval = 512; 1198 1199 if (q && q->limits.logical_block_size) 1200 retval = q->limits.logical_block_size; 1201 1202 return retval; 1203 } 1204 1205 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1206 { 1207 return queue_logical_block_size(bdev_get_queue(bdev)); 1208 } 1209 1210 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1211 { 1212 return q->limits.physical_block_size; 1213 } 1214 1215 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1216 { 1217 return queue_physical_block_size(bdev_get_queue(bdev)); 1218 } 1219 1220 static inline unsigned int queue_io_min(struct request_queue *q) 1221 { 1222 return q->limits.io_min; 1223 } 1224 1225 static inline int bdev_io_min(struct block_device *bdev) 1226 { 1227 return queue_io_min(bdev_get_queue(bdev)); 1228 } 1229 1230 static inline unsigned int queue_io_opt(struct request_queue *q) 1231 { 1232 return q->limits.io_opt; 1233 } 1234 1235 static inline int bdev_io_opt(struct block_device *bdev) 1236 { 1237 return queue_io_opt(bdev_get_queue(bdev)); 1238 } 1239 1240 static inline int queue_alignment_offset(struct request_queue *q) 1241 { 1242 if (q->limits.misaligned) 1243 return -1; 1244 1245 return q->limits.alignment_offset; 1246 } 1247 1248 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1249 { 1250 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1251 unsigned int alignment = sector_div(sector, granularity >> 9) << 9; 1252 1253 return (granularity + lim->alignment_offset - alignment) % granularity; 1254 } 1255 1256 static inline int bdev_alignment_offset(struct block_device *bdev) 1257 { 1258 struct request_queue *q = bdev_get_queue(bdev); 1259 1260 if (q->limits.misaligned) 1261 return -1; 1262 1263 if (bdev != bdev->bd_contains) 1264 return bdev->bd_part->alignment_offset; 1265 1266 return q->limits.alignment_offset; 1267 } 1268 1269 static inline int queue_discard_alignment(struct request_queue *q) 1270 { 1271 if (q->limits.discard_misaligned) 1272 return -1; 1273 1274 return q->limits.discard_alignment; 1275 } 1276 1277 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1278 { 1279 unsigned int alignment, granularity, offset; 1280 1281 if (!lim->max_discard_sectors) 1282 return 0; 1283 1284 /* Why are these in bytes, not sectors? */ 1285 alignment = lim->discard_alignment >> 9; 1286 granularity = lim->discard_granularity >> 9; 1287 if (!granularity) 1288 return 0; 1289 1290 /* Offset of the partition start in 'granularity' sectors */ 1291 offset = sector_div(sector, granularity); 1292 1293 /* And why do we do this modulus *again* in blkdev_issue_discard()? */ 1294 offset = (granularity + alignment - offset) % granularity; 1295 1296 /* Turn it back into bytes, gaah */ 1297 return offset << 9; 1298 } 1299 1300 static inline int bdev_discard_alignment(struct block_device *bdev) 1301 { 1302 struct request_queue *q = bdev_get_queue(bdev); 1303 1304 if (bdev != bdev->bd_contains) 1305 return bdev->bd_part->discard_alignment; 1306 1307 return q->limits.discard_alignment; 1308 } 1309 1310 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1311 { 1312 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) 1313 return 1; 1314 1315 return 0; 1316 } 1317 1318 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1319 { 1320 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1321 } 1322 1323 static inline unsigned int bdev_write_same(struct block_device *bdev) 1324 { 1325 struct request_queue *q = bdev_get_queue(bdev); 1326 1327 if (q) 1328 return q->limits.max_write_same_sectors; 1329 1330 return 0; 1331 } 1332 1333 static inline int queue_dma_alignment(struct request_queue *q) 1334 { 1335 return q ? q->dma_alignment : 511; 1336 } 1337 1338 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1339 unsigned int len) 1340 { 1341 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1342 return !(addr & alignment) && !(len & alignment); 1343 } 1344 1345 /* assumes size > 256 */ 1346 static inline unsigned int blksize_bits(unsigned int size) 1347 { 1348 unsigned int bits = 8; 1349 do { 1350 bits++; 1351 size >>= 1; 1352 } while (size > 256); 1353 return bits; 1354 } 1355 1356 static inline unsigned int block_size(struct block_device *bdev) 1357 { 1358 return bdev->bd_block_size; 1359 } 1360 1361 static inline bool queue_flush_queueable(struct request_queue *q) 1362 { 1363 return !q->flush_not_queueable; 1364 } 1365 1366 typedef struct {struct page *v;} Sector; 1367 1368 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1369 1370 static inline void put_dev_sector(Sector p) 1371 { 1372 page_cache_release(p.v); 1373 } 1374 1375 /* 1376 * Check if adding a bio_vec after bprv with offset would create a gap in 1377 * the SG list. Most drivers don't care about this, but some do. 1378 */ 1379 static inline bool bvec_gap_to_prev(struct request_queue *q, 1380 struct bio_vec *bprv, unsigned int offset) 1381 { 1382 if (!queue_virt_boundary(q)) 1383 return false; 1384 return offset || 1385 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); 1386 } 1387 1388 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev, 1389 struct bio *next) 1390 { 1391 if (!bio_has_data(prev)) 1392 return false; 1393 1394 return bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1], 1395 next->bi_io_vec[0].bv_offset); 1396 } 1397 1398 static inline bool req_gap_back_merge(struct request *req, struct bio *bio) 1399 { 1400 return bio_will_gap(req->q, req->biotail, bio); 1401 } 1402 1403 static inline bool req_gap_front_merge(struct request *req, struct bio *bio) 1404 { 1405 return bio_will_gap(req->q, bio, req->bio); 1406 } 1407 1408 struct work_struct; 1409 int kblockd_schedule_work(struct work_struct *work); 1410 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay); 1411 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay); 1412 1413 #ifdef CONFIG_BLK_CGROUP 1414 /* 1415 * This should not be using sched_clock(). A real patch is in progress 1416 * to fix this up, until that is in place we need to disable preemption 1417 * around sched_clock() in this function and set_io_start_time_ns(). 1418 */ 1419 static inline void set_start_time_ns(struct request *req) 1420 { 1421 preempt_disable(); 1422 req->start_time_ns = sched_clock(); 1423 preempt_enable(); 1424 } 1425 1426 static inline void set_io_start_time_ns(struct request *req) 1427 { 1428 preempt_disable(); 1429 req->io_start_time_ns = sched_clock(); 1430 preempt_enable(); 1431 } 1432 1433 static inline uint64_t rq_start_time_ns(struct request *req) 1434 { 1435 return req->start_time_ns; 1436 } 1437 1438 static inline uint64_t rq_io_start_time_ns(struct request *req) 1439 { 1440 return req->io_start_time_ns; 1441 } 1442 #else 1443 static inline void set_start_time_ns(struct request *req) {} 1444 static inline void set_io_start_time_ns(struct request *req) {} 1445 static inline uint64_t rq_start_time_ns(struct request *req) 1446 { 1447 return 0; 1448 } 1449 static inline uint64_t rq_io_start_time_ns(struct request *req) 1450 { 1451 return 0; 1452 } 1453 #endif 1454 1455 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1456 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1457 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1458 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1459 1460 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1461 1462 enum blk_integrity_flags { 1463 BLK_INTEGRITY_VERIFY = 1 << 0, 1464 BLK_INTEGRITY_GENERATE = 1 << 1, 1465 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2, 1466 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3, 1467 }; 1468 1469 struct blk_integrity_iter { 1470 void *prot_buf; 1471 void *data_buf; 1472 sector_t seed; 1473 unsigned int data_size; 1474 unsigned short interval; 1475 const char *disk_name; 1476 }; 1477 1478 typedef int (integrity_processing_fn) (struct blk_integrity_iter *); 1479 1480 struct blk_integrity_profile { 1481 integrity_processing_fn *generate_fn; 1482 integrity_processing_fn *verify_fn; 1483 const char *name; 1484 }; 1485 1486 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *); 1487 extern void blk_integrity_unregister(struct gendisk *); 1488 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1489 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1490 struct scatterlist *); 1491 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1492 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, 1493 struct request *); 1494 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, 1495 struct bio *); 1496 1497 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1498 { 1499 struct blk_integrity *bi = &disk->queue->integrity; 1500 1501 if (!bi->profile) 1502 return NULL; 1503 1504 return bi; 1505 } 1506 1507 static inline 1508 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1509 { 1510 return blk_get_integrity(bdev->bd_disk); 1511 } 1512 1513 static inline bool blk_integrity_rq(struct request *rq) 1514 { 1515 return rq->cmd_flags & REQ_INTEGRITY; 1516 } 1517 1518 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1519 unsigned int segs) 1520 { 1521 q->limits.max_integrity_segments = segs; 1522 } 1523 1524 static inline unsigned short 1525 queue_max_integrity_segments(struct request_queue *q) 1526 { 1527 return q->limits.max_integrity_segments; 1528 } 1529 1530 static inline bool integrity_req_gap_back_merge(struct request *req, 1531 struct bio *next) 1532 { 1533 struct bio_integrity_payload *bip = bio_integrity(req->bio); 1534 struct bio_integrity_payload *bip_next = bio_integrity(next); 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 static inline bool integrity_req_gap_front_merge(struct request *req, 1541 struct bio *bio) 1542 { 1543 struct bio_integrity_payload *bip = bio_integrity(bio); 1544 struct bio_integrity_payload *bip_next = bio_integrity(req->bio); 1545 1546 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1547 bip_next->bip_vec[0].bv_offset); 1548 } 1549 1550 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1551 1552 struct bio; 1553 struct block_device; 1554 struct gendisk; 1555 struct blk_integrity; 1556 1557 static inline int blk_integrity_rq(struct request *rq) 1558 { 1559 return 0; 1560 } 1561 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1562 struct bio *b) 1563 { 1564 return 0; 1565 } 1566 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1567 struct bio *b, 1568 struct scatterlist *s) 1569 { 1570 return 0; 1571 } 1572 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1573 { 1574 return NULL; 1575 } 1576 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1577 { 1578 return NULL; 1579 } 1580 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1581 { 1582 return 0; 1583 } 1584 static inline void blk_integrity_register(struct gendisk *d, 1585 struct blk_integrity *b) 1586 { 1587 } 1588 static inline void blk_integrity_unregister(struct gendisk *d) 1589 { 1590 } 1591 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1592 unsigned int segs) 1593 { 1594 } 1595 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1596 { 1597 return 0; 1598 } 1599 static inline bool blk_integrity_merge_rq(struct request_queue *rq, 1600 struct request *r1, 1601 struct request *r2) 1602 { 1603 return true; 1604 } 1605 static inline bool blk_integrity_merge_bio(struct request_queue *rq, 1606 struct request *r, 1607 struct bio *b) 1608 { 1609 return true; 1610 } 1611 1612 static inline bool integrity_req_gap_back_merge(struct request *req, 1613 struct bio *next) 1614 { 1615 return false; 1616 } 1617 static inline bool integrity_req_gap_front_merge(struct request *req, 1618 struct bio *bio) 1619 { 1620 return false; 1621 } 1622 1623 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1624 1625 /** 1626 * struct blk_dax_ctl - control and output parameters for ->direct_access 1627 * @sector: (input) offset relative to a block_device 1628 * @addr: (output) kernel virtual address for @sector populated by driver 1629 * @pfn: (output) page frame number for @addr populated by driver 1630 * @size: (input) number of bytes requested 1631 */ 1632 struct blk_dax_ctl { 1633 sector_t sector; 1634 void __pmem *addr; 1635 long size; 1636 pfn_t pfn; 1637 }; 1638 1639 struct block_device_operations { 1640 int (*open) (struct block_device *, fmode_t); 1641 void (*release) (struct gendisk *, fmode_t); 1642 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw); 1643 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1644 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1645 long (*direct_access)(struct block_device *, sector_t, void __pmem **, 1646 pfn_t *); 1647 unsigned int (*check_events) (struct gendisk *disk, 1648 unsigned int clearing); 1649 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1650 int (*media_changed) (struct gendisk *); 1651 void (*unlock_native_capacity) (struct gendisk *); 1652 int (*revalidate_disk) (struct gendisk *); 1653 int (*getgeo)(struct block_device *, struct hd_geometry *); 1654 /* this callback is with swap_lock and sometimes page table lock held */ 1655 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1656 struct module *owner; 1657 const struct pr_ops *pr_ops; 1658 }; 1659 1660 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1661 unsigned long); 1662 extern int bdev_read_page(struct block_device *, sector_t, struct page *); 1663 extern int bdev_write_page(struct block_device *, sector_t, struct page *, 1664 struct writeback_control *); 1665 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *); 1666 #else /* CONFIG_BLOCK */ 1667 1668 struct block_device; 1669 1670 /* 1671 * stubs for when the block layer is configured out 1672 */ 1673 #define buffer_heads_over_limit 0 1674 1675 static inline long nr_blockdev_pages(void) 1676 { 1677 return 0; 1678 } 1679 1680 struct blk_plug { 1681 }; 1682 1683 static inline void blk_start_plug(struct blk_plug *plug) 1684 { 1685 } 1686 1687 static inline void blk_finish_plug(struct blk_plug *plug) 1688 { 1689 } 1690 1691 static inline void blk_flush_plug(struct task_struct *task) 1692 { 1693 } 1694 1695 static inline void blk_schedule_flush_plug(struct task_struct *task) 1696 { 1697 } 1698 1699 1700 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1701 { 1702 return false; 1703 } 1704 1705 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, 1706 sector_t *error_sector) 1707 { 1708 return 0; 1709 } 1710 1711 #endif /* CONFIG_BLOCK */ 1712 1713 #endif 1714