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 u64 fifo_time; 94 }; 95 96 struct request_queue *q; 97 struct blk_mq_ctx *mq_ctx; 98 99 int cpu; 100 unsigned cmd_type; 101 u64 cmd_flags; 102 unsigned long atomic_flags; 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 #define REQ_OP_SHIFT (8 * sizeof(u64) - REQ_OP_BITS) 203 #define req_op(req) ((req)->cmd_flags >> REQ_OP_SHIFT) 204 205 #define req_set_op(req, op) do { \ 206 WARN_ON(op >= (1 << REQ_OP_BITS)); \ 207 (req)->cmd_flags &= ((1ULL << REQ_OP_SHIFT) - 1); \ 208 (req)->cmd_flags |= ((u64) (op) << REQ_OP_SHIFT); \ 209 } while (0) 210 211 #define req_set_op_attrs(req, op, flags) do { \ 212 req_set_op(req, op); \ 213 (req)->cmd_flags |= flags; \ 214 } while (0) 215 216 static inline unsigned short req_get_ioprio(struct request *req) 217 { 218 return req->ioprio; 219 } 220 221 #include <linux/elevator.h> 222 223 struct blk_queue_ctx; 224 225 typedef void (request_fn_proc) (struct request_queue *q); 226 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio); 227 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 228 typedef void (unprep_rq_fn) (struct request_queue *, struct request *); 229 230 struct bio_vec; 231 typedef void (softirq_done_fn)(struct request *); 232 typedef int (dma_drain_needed_fn)(struct request *); 233 typedef int (lld_busy_fn) (struct request_queue *q); 234 typedef int (bsg_job_fn) (struct bsg_job *); 235 236 enum blk_eh_timer_return { 237 BLK_EH_NOT_HANDLED, 238 BLK_EH_HANDLED, 239 BLK_EH_RESET_TIMER, 240 }; 241 242 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 243 244 enum blk_queue_state { 245 Queue_down, 246 Queue_up, 247 }; 248 249 struct blk_queue_tag { 250 struct request **tag_index; /* map of busy tags */ 251 unsigned long *tag_map; /* bit map of free/busy tags */ 252 int busy; /* current depth */ 253 int max_depth; /* what we will send to device */ 254 int real_max_depth; /* what the array can hold */ 255 atomic_t refcnt; /* map can be shared */ 256 int alloc_policy; /* tag allocation policy */ 257 int next_tag; /* next tag */ 258 }; 259 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */ 260 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */ 261 262 #define BLK_SCSI_MAX_CMDS (256) 263 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 264 265 struct queue_limits { 266 unsigned long bounce_pfn; 267 unsigned long seg_boundary_mask; 268 unsigned long virt_boundary_mask; 269 270 unsigned int max_hw_sectors; 271 unsigned int max_dev_sectors; 272 unsigned int chunk_sectors; 273 unsigned int max_sectors; 274 unsigned int max_segment_size; 275 unsigned int physical_block_size; 276 unsigned int alignment_offset; 277 unsigned int io_min; 278 unsigned int io_opt; 279 unsigned int max_discard_sectors; 280 unsigned int max_hw_discard_sectors; 281 unsigned int max_write_same_sectors; 282 unsigned int discard_granularity; 283 unsigned int discard_alignment; 284 285 unsigned short logical_block_size; 286 unsigned short max_segments; 287 unsigned short max_integrity_segments; 288 289 unsigned char misaligned; 290 unsigned char discard_misaligned; 291 unsigned char cluster; 292 unsigned char discard_zeroes_data; 293 unsigned char raid_partial_stripes_expensive; 294 }; 295 296 struct request_queue { 297 /* 298 * Together with queue_head for cacheline sharing 299 */ 300 struct list_head queue_head; 301 struct request *last_merge; 302 struct elevator_queue *elevator; 303 int nr_rqs[2]; /* # allocated [a]sync rqs */ 304 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */ 305 306 /* 307 * If blkcg is not used, @q->root_rl serves all requests. If blkcg 308 * is used, root blkg allocates from @q->root_rl and all other 309 * blkgs from their own blkg->rl. Which one to use should be 310 * determined using bio_request_list(). 311 */ 312 struct request_list root_rl; 313 314 request_fn_proc *request_fn; 315 make_request_fn *make_request_fn; 316 prep_rq_fn *prep_rq_fn; 317 unprep_rq_fn *unprep_rq_fn; 318 softirq_done_fn *softirq_done_fn; 319 rq_timed_out_fn *rq_timed_out_fn; 320 dma_drain_needed_fn *dma_drain_needed; 321 lld_busy_fn *lld_busy_fn; 322 323 struct blk_mq_ops *mq_ops; 324 325 unsigned int *mq_map; 326 327 /* sw queues */ 328 struct blk_mq_ctx __percpu *queue_ctx; 329 unsigned int nr_queues; 330 331 /* hw dispatch queues */ 332 struct blk_mq_hw_ctx **queue_hw_ctx; 333 unsigned int nr_hw_queues; 334 335 /* 336 * Dispatch queue sorting 337 */ 338 sector_t end_sector; 339 struct request *boundary_rq; 340 341 /* 342 * Delayed queue handling 343 */ 344 struct delayed_work delay_work; 345 346 struct backing_dev_info backing_dev_info; 347 348 /* 349 * The queue owner gets to use this for whatever they like. 350 * ll_rw_blk doesn't touch it. 351 */ 352 void *queuedata; 353 354 /* 355 * various queue flags, see QUEUE_* below 356 */ 357 unsigned long queue_flags; 358 359 /* 360 * ida allocated id for this queue. Used to index queues from 361 * ioctx. 362 */ 363 int id; 364 365 /* 366 * queue needs bounce pages for pages above this limit 367 */ 368 gfp_t bounce_gfp; 369 370 /* 371 * protects queue structures from reentrancy. ->__queue_lock should 372 * _never_ be used directly, it is queue private. always use 373 * ->queue_lock. 374 */ 375 spinlock_t __queue_lock; 376 spinlock_t *queue_lock; 377 378 /* 379 * queue kobject 380 */ 381 struct kobject kobj; 382 383 /* 384 * mq queue kobject 385 */ 386 struct kobject mq_kobj; 387 388 #ifdef CONFIG_BLK_DEV_INTEGRITY 389 struct blk_integrity integrity; 390 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 391 392 #ifdef CONFIG_PM 393 struct device *dev; 394 int rpm_status; 395 unsigned int nr_pending; 396 #endif 397 398 /* 399 * queue settings 400 */ 401 unsigned long nr_requests; /* Max # of requests */ 402 unsigned int nr_congestion_on; 403 unsigned int nr_congestion_off; 404 unsigned int nr_batching; 405 406 unsigned int dma_drain_size; 407 void *dma_drain_buffer; 408 unsigned int dma_pad_mask; 409 unsigned int dma_alignment; 410 411 struct blk_queue_tag *queue_tags; 412 struct list_head tag_busy_list; 413 414 unsigned int nr_sorted; 415 unsigned int in_flight[2]; 416 /* 417 * Number of active block driver functions for which blk_drain_queue() 418 * must wait. Must be incremented around functions that unlock the 419 * queue_lock internally, e.g. scsi_request_fn(). 420 */ 421 unsigned int request_fn_active; 422 423 unsigned int rq_timeout; 424 struct timer_list timeout; 425 struct work_struct timeout_work; 426 struct list_head timeout_list; 427 428 struct list_head icq_list; 429 #ifdef CONFIG_BLK_CGROUP 430 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); 431 struct blkcg_gq *root_blkg; 432 struct list_head blkg_list; 433 #endif 434 435 struct queue_limits limits; 436 437 /* 438 * sg stuff 439 */ 440 unsigned int sg_timeout; 441 unsigned int sg_reserved_size; 442 int node; 443 #ifdef CONFIG_BLK_DEV_IO_TRACE 444 struct blk_trace *blk_trace; 445 #endif 446 /* 447 * for flush operations 448 */ 449 struct blk_flush_queue *fq; 450 451 struct list_head requeue_list; 452 spinlock_t requeue_lock; 453 struct work_struct requeue_work; 454 455 struct mutex sysfs_lock; 456 457 int bypass_depth; 458 atomic_t mq_freeze_depth; 459 460 #if defined(CONFIG_BLK_DEV_BSG) 461 bsg_job_fn *bsg_job_fn; 462 int bsg_job_size; 463 struct bsg_class_device bsg_dev; 464 #endif 465 466 #ifdef CONFIG_BLK_DEV_THROTTLING 467 /* Throttle data */ 468 struct throtl_data *td; 469 #endif 470 struct rcu_head rcu_head; 471 wait_queue_head_t mq_freeze_wq; 472 struct percpu_ref q_usage_counter; 473 struct list_head all_q_node; 474 475 struct blk_mq_tag_set *tag_set; 476 struct list_head tag_set_list; 477 struct bio_set *bio_split; 478 479 bool mq_sysfs_init_done; 480 }; 481 482 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 483 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 484 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 485 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 486 #define QUEUE_FLAG_DYING 5 /* queue being torn down */ 487 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */ 488 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ 489 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ 490 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ 491 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ 492 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ 493 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ 494 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 495 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ 496 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ 497 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ 498 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ 499 #define QUEUE_FLAG_SECERASE 17 /* supports secure erase */ 500 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ 501 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */ 502 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */ 503 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/ 504 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */ 505 #define QUEUE_FLAG_WC 23 /* Write back caching */ 506 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */ 507 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */ 508 #define QUEUE_FLAG_DAX 26 /* device supports DAX */ 509 510 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 511 (1 << QUEUE_FLAG_STACKABLE) | \ 512 (1 << QUEUE_FLAG_SAME_COMP) | \ 513 (1 << QUEUE_FLAG_ADD_RANDOM)) 514 515 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 516 (1 << QUEUE_FLAG_STACKABLE) | \ 517 (1 << QUEUE_FLAG_SAME_COMP) | \ 518 (1 << QUEUE_FLAG_POLL)) 519 520 static inline void queue_lockdep_assert_held(struct request_queue *q) 521 { 522 if (q->queue_lock) 523 lockdep_assert_held(q->queue_lock); 524 } 525 526 static inline void queue_flag_set_unlocked(unsigned int flag, 527 struct request_queue *q) 528 { 529 __set_bit(flag, &q->queue_flags); 530 } 531 532 static inline int queue_flag_test_and_clear(unsigned int flag, 533 struct request_queue *q) 534 { 535 queue_lockdep_assert_held(q); 536 537 if (test_bit(flag, &q->queue_flags)) { 538 __clear_bit(flag, &q->queue_flags); 539 return 1; 540 } 541 542 return 0; 543 } 544 545 static inline int queue_flag_test_and_set(unsigned int flag, 546 struct request_queue *q) 547 { 548 queue_lockdep_assert_held(q); 549 550 if (!test_bit(flag, &q->queue_flags)) { 551 __set_bit(flag, &q->queue_flags); 552 return 0; 553 } 554 555 return 1; 556 } 557 558 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 559 { 560 queue_lockdep_assert_held(q); 561 __set_bit(flag, &q->queue_flags); 562 } 563 564 static inline void queue_flag_clear_unlocked(unsigned int flag, 565 struct request_queue *q) 566 { 567 __clear_bit(flag, &q->queue_flags); 568 } 569 570 static inline int queue_in_flight(struct request_queue *q) 571 { 572 return q->in_flight[0] + q->in_flight[1]; 573 } 574 575 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 576 { 577 queue_lockdep_assert_held(q); 578 __clear_bit(flag, &q->queue_flags); 579 } 580 581 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 582 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 583 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags) 584 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 585 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags) 586 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags) 587 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 588 #define blk_queue_noxmerges(q) \ 589 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 590 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 591 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 592 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 593 #define blk_queue_stackable(q) \ 594 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 595 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 596 #define blk_queue_secure_erase(q) \ 597 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags)) 598 #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags) 599 600 #define blk_noretry_request(rq) \ 601 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 602 REQ_FAILFAST_DRIVER)) 603 604 #define blk_account_rq(rq) \ 605 (((rq)->cmd_flags & REQ_STARTED) && \ 606 ((rq)->cmd_type == REQ_TYPE_FS)) 607 608 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 609 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 610 /* rq->queuelist of dequeued request must be list_empty() */ 611 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 612 613 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 614 615 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ) 616 617 /* 618 * Driver can handle struct request, if it either has an old style 619 * request_fn defined, or is blk-mq based. 620 */ 621 static inline bool queue_is_rq_based(struct request_queue *q) 622 { 623 return q->request_fn || q->mq_ops; 624 } 625 626 static inline unsigned int blk_queue_cluster(struct request_queue *q) 627 { 628 return q->limits.cluster; 629 } 630 631 /* 632 * We regard a request as sync, if either a read or a sync write 633 */ 634 static inline bool rw_is_sync(int op, unsigned int rw_flags) 635 { 636 return op == REQ_OP_READ || (rw_flags & REQ_SYNC); 637 } 638 639 static inline bool rq_is_sync(struct request *rq) 640 { 641 return rw_is_sync(req_op(rq), rq->cmd_flags); 642 } 643 644 static inline bool blk_rl_full(struct request_list *rl, bool sync) 645 { 646 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 647 648 return rl->flags & flag; 649 } 650 651 static inline void blk_set_rl_full(struct request_list *rl, bool sync) 652 { 653 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 654 655 rl->flags |= flag; 656 } 657 658 static inline void blk_clear_rl_full(struct request_list *rl, bool sync) 659 { 660 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 661 662 rl->flags &= ~flag; 663 } 664 665 static inline bool rq_mergeable(struct request *rq) 666 { 667 if (rq->cmd_type != REQ_TYPE_FS) 668 return false; 669 670 if (req_op(rq) == REQ_OP_FLUSH) 671 return false; 672 673 if (rq->cmd_flags & REQ_NOMERGE_FLAGS) 674 return false; 675 676 return true; 677 } 678 679 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b) 680 { 681 if (bio_data(a) == bio_data(b)) 682 return true; 683 684 return false; 685 } 686 687 /* 688 * q->prep_rq_fn return values 689 */ 690 enum { 691 BLKPREP_OK, /* serve it */ 692 BLKPREP_KILL, /* fatal error, kill, return -EIO */ 693 BLKPREP_DEFER, /* leave on queue */ 694 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */ 695 }; 696 697 extern unsigned long blk_max_low_pfn, blk_max_pfn; 698 699 /* 700 * standard bounce addresses: 701 * 702 * BLK_BOUNCE_HIGH : bounce all highmem pages 703 * BLK_BOUNCE_ANY : don't bounce anything 704 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 705 */ 706 707 #if BITS_PER_LONG == 32 708 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 709 #else 710 #define BLK_BOUNCE_HIGH -1ULL 711 #endif 712 #define BLK_BOUNCE_ANY (-1ULL) 713 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 714 715 /* 716 * default timeout for SG_IO if none specified 717 */ 718 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 719 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 720 721 #ifdef CONFIG_BOUNCE 722 extern int init_emergency_isa_pool(void); 723 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 724 #else 725 static inline int init_emergency_isa_pool(void) 726 { 727 return 0; 728 } 729 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 730 { 731 } 732 #endif /* CONFIG_MMU */ 733 734 struct rq_map_data { 735 struct page **pages; 736 int page_order; 737 int nr_entries; 738 unsigned long offset; 739 int null_mapped; 740 int from_user; 741 }; 742 743 struct req_iterator { 744 struct bvec_iter iter; 745 struct bio *bio; 746 }; 747 748 /* This should not be used directly - use rq_for_each_segment */ 749 #define for_each_bio(_bio) \ 750 for (; _bio; _bio = _bio->bi_next) 751 #define __rq_for_each_bio(_bio, rq) \ 752 if ((rq->bio)) \ 753 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 754 755 #define rq_for_each_segment(bvl, _rq, _iter) \ 756 __rq_for_each_bio(_iter.bio, _rq) \ 757 bio_for_each_segment(bvl, _iter.bio, _iter.iter) 758 759 #define rq_iter_last(bvec, _iter) \ 760 (_iter.bio->bi_next == NULL && \ 761 bio_iter_last(bvec, _iter.iter)) 762 763 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 764 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 765 #endif 766 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 767 extern void rq_flush_dcache_pages(struct request *rq); 768 #else 769 static inline void rq_flush_dcache_pages(struct request *rq) 770 { 771 } 772 #endif 773 774 #ifdef CONFIG_PRINTK 775 #define vfs_msg(sb, level, fmt, ...) \ 776 __vfs_msg(sb, level, fmt, ##__VA_ARGS__) 777 #else 778 #define vfs_msg(sb, level, fmt, ...) \ 779 do { \ 780 no_printk(fmt, ##__VA_ARGS__); \ 781 __vfs_msg(sb, "", " "); \ 782 } while (0) 783 #endif 784 785 extern int blk_register_queue(struct gendisk *disk); 786 extern void blk_unregister_queue(struct gendisk *disk); 787 extern blk_qc_t generic_make_request(struct bio *bio); 788 extern void blk_rq_init(struct request_queue *q, struct request *rq); 789 extern void blk_put_request(struct request *); 790 extern void __blk_put_request(struct request_queue *, struct request *); 791 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 792 extern void blk_rq_set_block_pc(struct request *); 793 extern void blk_requeue_request(struct request_queue *, struct request *); 794 extern void blk_add_request_payload(struct request *rq, struct page *page, 795 int offset, unsigned int len); 796 extern int blk_lld_busy(struct request_queue *q); 797 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 798 struct bio_set *bs, gfp_t gfp_mask, 799 int (*bio_ctr)(struct bio *, struct bio *, void *), 800 void *data); 801 extern void blk_rq_unprep_clone(struct request *rq); 802 extern int blk_insert_cloned_request(struct request_queue *q, 803 struct request *rq); 804 extern int blk_rq_append_bio(struct request *rq, struct bio *bio); 805 extern void blk_delay_queue(struct request_queue *, unsigned long); 806 extern void blk_queue_split(struct request_queue *, struct bio **, 807 struct bio_set *); 808 extern void blk_recount_segments(struct request_queue *, struct bio *); 809 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 810 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 811 unsigned int, void __user *); 812 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 813 unsigned int, void __user *); 814 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 815 struct scsi_ioctl_command __user *); 816 817 extern int blk_queue_enter(struct request_queue *q, bool nowait); 818 extern void blk_queue_exit(struct request_queue *q); 819 extern void blk_start_queue(struct request_queue *q); 820 extern void blk_start_queue_async(struct request_queue *q); 821 extern void blk_stop_queue(struct request_queue *q); 822 extern void blk_sync_queue(struct request_queue *q); 823 extern void __blk_stop_queue(struct request_queue *q); 824 extern void __blk_run_queue(struct request_queue *q); 825 extern void __blk_run_queue_uncond(struct request_queue *q); 826 extern void blk_run_queue(struct request_queue *); 827 extern void blk_run_queue_async(struct request_queue *q); 828 extern int blk_rq_map_user(struct request_queue *, struct request *, 829 struct rq_map_data *, void __user *, unsigned long, 830 gfp_t); 831 extern int blk_rq_unmap_user(struct bio *); 832 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 833 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 834 struct rq_map_data *, const struct iov_iter *, 835 gfp_t); 836 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 837 struct request *, int); 838 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 839 struct request *, int, rq_end_io_fn *); 840 841 bool blk_poll(struct request_queue *q, blk_qc_t cookie); 842 843 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 844 { 845 return bdev->bd_disk->queue; /* this is never NULL */ 846 } 847 848 /* 849 * blk_rq_pos() : the current sector 850 * blk_rq_bytes() : bytes left in the entire request 851 * blk_rq_cur_bytes() : bytes left in the current segment 852 * blk_rq_err_bytes() : bytes left till the next error boundary 853 * blk_rq_sectors() : sectors left in the entire request 854 * blk_rq_cur_sectors() : sectors left in the current segment 855 */ 856 static inline sector_t blk_rq_pos(const struct request *rq) 857 { 858 return rq->__sector; 859 } 860 861 static inline unsigned int blk_rq_bytes(const struct request *rq) 862 { 863 return rq->__data_len; 864 } 865 866 static inline int blk_rq_cur_bytes(const struct request *rq) 867 { 868 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 869 } 870 871 extern unsigned int blk_rq_err_bytes(const struct request *rq); 872 873 static inline unsigned int blk_rq_sectors(const struct request *rq) 874 { 875 return blk_rq_bytes(rq) >> 9; 876 } 877 878 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 879 { 880 return blk_rq_cur_bytes(rq) >> 9; 881 } 882 883 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q, 884 int op) 885 { 886 if (unlikely(op == REQ_OP_DISCARD)) 887 return min(q->limits.max_discard_sectors, UINT_MAX >> 9); 888 889 if (unlikely(op == REQ_OP_WRITE_SAME)) 890 return q->limits.max_write_same_sectors; 891 892 return q->limits.max_sectors; 893 } 894 895 /* 896 * Return maximum size of a request at given offset. Only valid for 897 * file system requests. 898 */ 899 static inline unsigned int blk_max_size_offset(struct request_queue *q, 900 sector_t offset) 901 { 902 if (!q->limits.chunk_sectors) 903 return q->limits.max_sectors; 904 905 return q->limits.chunk_sectors - 906 (offset & (q->limits.chunk_sectors - 1)); 907 } 908 909 static inline unsigned int blk_rq_get_max_sectors(struct request *rq, 910 sector_t offset) 911 { 912 struct request_queue *q = rq->q; 913 914 if (unlikely(rq->cmd_type != REQ_TYPE_FS)) 915 return q->limits.max_hw_sectors; 916 917 if (!q->limits.chunk_sectors || (req_op(rq) == REQ_OP_DISCARD)) 918 return blk_queue_get_max_sectors(q, req_op(rq)); 919 920 return min(blk_max_size_offset(q, offset), 921 blk_queue_get_max_sectors(q, req_op(rq))); 922 } 923 924 static inline unsigned int blk_rq_count_bios(struct request *rq) 925 { 926 unsigned int nr_bios = 0; 927 struct bio *bio; 928 929 __rq_for_each_bio(bio, rq) 930 nr_bios++; 931 932 return nr_bios; 933 } 934 935 /* 936 * Request issue related functions. 937 */ 938 extern struct request *blk_peek_request(struct request_queue *q); 939 extern void blk_start_request(struct request *rq); 940 extern struct request *blk_fetch_request(struct request_queue *q); 941 942 /* 943 * Request completion related functions. 944 * 945 * blk_update_request() completes given number of bytes and updates 946 * the request without completing it. 947 * 948 * blk_end_request() and friends. __blk_end_request() must be called 949 * with the request queue spinlock acquired. 950 * 951 * Several drivers define their own end_request and call 952 * blk_end_request() for parts of the original function. 953 * This prevents code duplication in drivers. 954 */ 955 extern bool blk_update_request(struct request *rq, int error, 956 unsigned int nr_bytes); 957 extern void blk_finish_request(struct request *rq, int error); 958 extern bool blk_end_request(struct request *rq, int error, 959 unsigned int nr_bytes); 960 extern void blk_end_request_all(struct request *rq, int error); 961 extern bool blk_end_request_cur(struct request *rq, int error); 962 extern bool blk_end_request_err(struct request *rq, int error); 963 extern bool __blk_end_request(struct request *rq, int error, 964 unsigned int nr_bytes); 965 extern void __blk_end_request_all(struct request *rq, int error); 966 extern bool __blk_end_request_cur(struct request *rq, int error); 967 extern bool __blk_end_request_err(struct request *rq, int error); 968 969 extern void blk_complete_request(struct request *); 970 extern void __blk_complete_request(struct request *); 971 extern void blk_abort_request(struct request *); 972 extern void blk_unprep_request(struct request *); 973 974 /* 975 * Access functions for manipulating queue properties 976 */ 977 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 978 spinlock_t *lock, int node_id); 979 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 980 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 981 request_fn_proc *, spinlock_t *); 982 extern void blk_cleanup_queue(struct request_queue *); 983 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 984 extern void blk_queue_bounce_limit(struct request_queue *, u64); 985 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 986 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int); 987 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 988 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 989 extern void blk_queue_max_discard_sectors(struct request_queue *q, 990 unsigned int max_discard_sectors); 991 extern void blk_queue_max_write_same_sectors(struct request_queue *q, 992 unsigned int max_write_same_sectors); 993 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 994 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 995 extern void blk_queue_alignment_offset(struct request_queue *q, 996 unsigned int alignment); 997 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 998 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 999 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 1000 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 1001 extern void blk_set_default_limits(struct queue_limits *lim); 1002 extern void blk_set_stacking_limits(struct queue_limits *lim); 1003 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 1004 sector_t offset); 1005 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 1006 sector_t offset); 1007 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 1008 sector_t offset); 1009 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 1010 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 1011 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 1012 extern int blk_queue_dma_drain(struct request_queue *q, 1013 dma_drain_needed_fn *dma_drain_needed, 1014 void *buf, unsigned int size); 1015 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 1016 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 1017 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long); 1018 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 1019 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 1020 extern void blk_queue_dma_alignment(struct request_queue *, int); 1021 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 1022 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 1023 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 1024 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 1025 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 1026 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua); 1027 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 1028 1029 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 1030 extern void blk_dump_rq_flags(struct request *, char *); 1031 extern long nr_blockdev_pages(void); 1032 1033 bool __must_check blk_get_queue(struct request_queue *); 1034 struct request_queue *blk_alloc_queue(gfp_t); 1035 struct request_queue *blk_alloc_queue_node(gfp_t, int); 1036 extern void blk_put_queue(struct request_queue *); 1037 extern void blk_set_queue_dying(struct request_queue *); 1038 1039 /* 1040 * block layer runtime pm functions 1041 */ 1042 #ifdef CONFIG_PM 1043 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev); 1044 extern int blk_pre_runtime_suspend(struct request_queue *q); 1045 extern void blk_post_runtime_suspend(struct request_queue *q, int err); 1046 extern void blk_pre_runtime_resume(struct request_queue *q); 1047 extern void blk_post_runtime_resume(struct request_queue *q, int err); 1048 extern void blk_set_runtime_active(struct request_queue *q); 1049 #else 1050 static inline void blk_pm_runtime_init(struct request_queue *q, 1051 struct device *dev) {} 1052 static inline int blk_pre_runtime_suspend(struct request_queue *q) 1053 { 1054 return -ENOSYS; 1055 } 1056 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {} 1057 static inline void blk_pre_runtime_resume(struct request_queue *q) {} 1058 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {} 1059 extern inline void blk_set_runtime_active(struct request_queue *q) {} 1060 #endif 1061 1062 /* 1063 * blk_plug permits building a queue of related requests by holding the I/O 1064 * fragments for a short period. This allows merging of sequential requests 1065 * into single larger request. As the requests are moved from a per-task list to 1066 * the device's request_queue in a batch, this results in improved scalability 1067 * as the lock contention for request_queue lock is reduced. 1068 * 1069 * It is ok not to disable preemption when adding the request to the plug list 1070 * or when attempting a merge, because blk_schedule_flush_list() will only flush 1071 * the plug list when the task sleeps by itself. For details, please see 1072 * schedule() where blk_schedule_flush_plug() is called. 1073 */ 1074 struct blk_plug { 1075 struct list_head list; /* requests */ 1076 struct list_head mq_list; /* blk-mq requests */ 1077 struct list_head cb_list; /* md requires an unplug callback */ 1078 }; 1079 #define BLK_MAX_REQUEST_COUNT 16 1080 1081 struct blk_plug_cb; 1082 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool); 1083 struct blk_plug_cb { 1084 struct list_head list; 1085 blk_plug_cb_fn callback; 1086 void *data; 1087 }; 1088 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, 1089 void *data, int size); 1090 extern void blk_start_plug(struct blk_plug *); 1091 extern void blk_finish_plug(struct blk_plug *); 1092 extern void blk_flush_plug_list(struct blk_plug *, bool); 1093 1094 static inline void blk_flush_plug(struct task_struct *tsk) 1095 { 1096 struct blk_plug *plug = tsk->plug; 1097 1098 if (plug) 1099 blk_flush_plug_list(plug, false); 1100 } 1101 1102 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 1103 { 1104 struct blk_plug *plug = tsk->plug; 1105 1106 if (plug) 1107 blk_flush_plug_list(plug, true); 1108 } 1109 1110 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1111 { 1112 struct blk_plug *plug = tsk->plug; 1113 1114 return plug && 1115 (!list_empty(&plug->list) || 1116 !list_empty(&plug->mq_list) || 1117 !list_empty(&plug->cb_list)); 1118 } 1119 1120 /* 1121 * tag stuff 1122 */ 1123 extern int blk_queue_start_tag(struct request_queue *, struct request *); 1124 extern struct request *blk_queue_find_tag(struct request_queue *, int); 1125 extern void blk_queue_end_tag(struct request_queue *, struct request *); 1126 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int); 1127 extern void blk_queue_free_tags(struct request_queue *); 1128 extern int blk_queue_resize_tags(struct request_queue *, int); 1129 extern void blk_queue_invalidate_tags(struct request_queue *); 1130 extern struct blk_queue_tag *blk_init_tags(int, int); 1131 extern void blk_free_tags(struct blk_queue_tag *); 1132 1133 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 1134 int tag) 1135 { 1136 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 1137 return NULL; 1138 return bqt->tag_index[tag]; 1139 } 1140 1141 1142 #define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */ 1143 #define BLKDEV_DISCARD_ZERO (1 << 1) /* must reliably zero data */ 1144 1145 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 1146 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1147 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 1148 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1149 sector_t nr_sects, gfp_t gfp_mask, int flags, 1150 struct bio **biop); 1151 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, 1152 sector_t nr_sects, gfp_t gfp_mask, struct page *page); 1153 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1154 sector_t nr_sects, gfp_t gfp_mask, bool discard); 1155 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 1156 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 1157 { 1158 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 1159 nr_blocks << (sb->s_blocksize_bits - 9), 1160 gfp_mask, flags); 1161 } 1162 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 1163 sector_t nr_blocks, gfp_t gfp_mask) 1164 { 1165 return blkdev_issue_zeroout(sb->s_bdev, 1166 block << (sb->s_blocksize_bits - 9), 1167 nr_blocks << (sb->s_blocksize_bits - 9), 1168 gfp_mask, true); 1169 } 1170 1171 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 1172 1173 enum blk_default_limits { 1174 BLK_MAX_SEGMENTS = 128, 1175 BLK_SAFE_MAX_SECTORS = 255, 1176 BLK_DEF_MAX_SECTORS = 2560, 1177 BLK_MAX_SEGMENT_SIZE = 65536, 1178 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 1179 }; 1180 1181 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1182 1183 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 1184 { 1185 return q->limits.bounce_pfn; 1186 } 1187 1188 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1189 { 1190 return q->limits.seg_boundary_mask; 1191 } 1192 1193 static inline unsigned long queue_virt_boundary(struct request_queue *q) 1194 { 1195 return q->limits.virt_boundary_mask; 1196 } 1197 1198 static inline unsigned int queue_max_sectors(struct request_queue *q) 1199 { 1200 return q->limits.max_sectors; 1201 } 1202 1203 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1204 { 1205 return q->limits.max_hw_sectors; 1206 } 1207 1208 static inline unsigned short queue_max_segments(struct request_queue *q) 1209 { 1210 return q->limits.max_segments; 1211 } 1212 1213 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1214 { 1215 return q->limits.max_segment_size; 1216 } 1217 1218 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1219 { 1220 int retval = 512; 1221 1222 if (q && q->limits.logical_block_size) 1223 retval = q->limits.logical_block_size; 1224 1225 return retval; 1226 } 1227 1228 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1229 { 1230 return queue_logical_block_size(bdev_get_queue(bdev)); 1231 } 1232 1233 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1234 { 1235 return q->limits.physical_block_size; 1236 } 1237 1238 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1239 { 1240 return queue_physical_block_size(bdev_get_queue(bdev)); 1241 } 1242 1243 static inline unsigned int queue_io_min(struct request_queue *q) 1244 { 1245 return q->limits.io_min; 1246 } 1247 1248 static inline int bdev_io_min(struct block_device *bdev) 1249 { 1250 return queue_io_min(bdev_get_queue(bdev)); 1251 } 1252 1253 static inline unsigned int queue_io_opt(struct request_queue *q) 1254 { 1255 return q->limits.io_opt; 1256 } 1257 1258 static inline int bdev_io_opt(struct block_device *bdev) 1259 { 1260 return queue_io_opt(bdev_get_queue(bdev)); 1261 } 1262 1263 static inline int queue_alignment_offset(struct request_queue *q) 1264 { 1265 if (q->limits.misaligned) 1266 return -1; 1267 1268 return q->limits.alignment_offset; 1269 } 1270 1271 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1272 { 1273 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1274 unsigned int alignment = sector_div(sector, granularity >> 9) << 9; 1275 1276 return (granularity + lim->alignment_offset - alignment) % granularity; 1277 } 1278 1279 static inline int bdev_alignment_offset(struct block_device *bdev) 1280 { 1281 struct request_queue *q = bdev_get_queue(bdev); 1282 1283 if (q->limits.misaligned) 1284 return -1; 1285 1286 if (bdev != bdev->bd_contains) 1287 return bdev->bd_part->alignment_offset; 1288 1289 return q->limits.alignment_offset; 1290 } 1291 1292 static inline int queue_discard_alignment(struct request_queue *q) 1293 { 1294 if (q->limits.discard_misaligned) 1295 return -1; 1296 1297 return q->limits.discard_alignment; 1298 } 1299 1300 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1301 { 1302 unsigned int alignment, granularity, offset; 1303 1304 if (!lim->max_discard_sectors) 1305 return 0; 1306 1307 /* Why are these in bytes, not sectors? */ 1308 alignment = lim->discard_alignment >> 9; 1309 granularity = lim->discard_granularity >> 9; 1310 if (!granularity) 1311 return 0; 1312 1313 /* Offset of the partition start in 'granularity' sectors */ 1314 offset = sector_div(sector, granularity); 1315 1316 /* And why do we do this modulus *again* in blkdev_issue_discard()? */ 1317 offset = (granularity + alignment - offset) % granularity; 1318 1319 /* Turn it back into bytes, gaah */ 1320 return offset << 9; 1321 } 1322 1323 static inline int bdev_discard_alignment(struct block_device *bdev) 1324 { 1325 struct request_queue *q = bdev_get_queue(bdev); 1326 1327 if (bdev != bdev->bd_contains) 1328 return bdev->bd_part->discard_alignment; 1329 1330 return q->limits.discard_alignment; 1331 } 1332 1333 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1334 { 1335 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) 1336 return 1; 1337 1338 return 0; 1339 } 1340 1341 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1342 { 1343 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1344 } 1345 1346 static inline unsigned int bdev_write_same(struct block_device *bdev) 1347 { 1348 struct request_queue *q = bdev_get_queue(bdev); 1349 1350 if (q) 1351 return q->limits.max_write_same_sectors; 1352 1353 return 0; 1354 } 1355 1356 static inline int queue_dma_alignment(struct request_queue *q) 1357 { 1358 return q ? q->dma_alignment : 511; 1359 } 1360 1361 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1362 unsigned int len) 1363 { 1364 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1365 return !(addr & alignment) && !(len & alignment); 1366 } 1367 1368 /* assumes size > 256 */ 1369 static inline unsigned int blksize_bits(unsigned int size) 1370 { 1371 unsigned int bits = 8; 1372 do { 1373 bits++; 1374 size >>= 1; 1375 } while (size > 256); 1376 return bits; 1377 } 1378 1379 static inline unsigned int block_size(struct block_device *bdev) 1380 { 1381 return bdev->bd_block_size; 1382 } 1383 1384 static inline bool queue_flush_queueable(struct request_queue *q) 1385 { 1386 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags); 1387 } 1388 1389 typedef struct {struct page *v;} Sector; 1390 1391 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1392 1393 static inline void put_dev_sector(Sector p) 1394 { 1395 put_page(p.v); 1396 } 1397 1398 static inline bool __bvec_gap_to_prev(struct request_queue *q, 1399 struct bio_vec *bprv, unsigned int offset) 1400 { 1401 return offset || 1402 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); 1403 } 1404 1405 /* 1406 * Check if adding a bio_vec after bprv with offset would create a gap in 1407 * the SG list. Most drivers don't care about this, but some do. 1408 */ 1409 static inline bool bvec_gap_to_prev(struct request_queue *q, 1410 struct bio_vec *bprv, unsigned int offset) 1411 { 1412 if (!queue_virt_boundary(q)) 1413 return false; 1414 return __bvec_gap_to_prev(q, bprv, offset); 1415 } 1416 1417 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev, 1418 struct bio *next) 1419 { 1420 if (bio_has_data(prev) && queue_virt_boundary(q)) { 1421 struct bio_vec pb, nb; 1422 1423 bio_get_last_bvec(prev, &pb); 1424 bio_get_first_bvec(next, &nb); 1425 1426 return __bvec_gap_to_prev(q, &pb, nb.bv_offset); 1427 } 1428 1429 return false; 1430 } 1431 1432 static inline bool req_gap_back_merge(struct request *req, struct bio *bio) 1433 { 1434 return bio_will_gap(req->q, req->biotail, bio); 1435 } 1436 1437 static inline bool req_gap_front_merge(struct request *req, struct bio *bio) 1438 { 1439 return bio_will_gap(req->q, bio, req->bio); 1440 } 1441 1442 struct work_struct; 1443 int kblockd_schedule_work(struct work_struct *work); 1444 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay); 1445 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay); 1446 1447 #ifdef CONFIG_BLK_CGROUP 1448 /* 1449 * This should not be using sched_clock(). A real patch is in progress 1450 * to fix this up, until that is in place we need to disable preemption 1451 * around sched_clock() in this function and set_io_start_time_ns(). 1452 */ 1453 static inline void set_start_time_ns(struct request *req) 1454 { 1455 preempt_disable(); 1456 req->start_time_ns = sched_clock(); 1457 preempt_enable(); 1458 } 1459 1460 static inline void set_io_start_time_ns(struct request *req) 1461 { 1462 preempt_disable(); 1463 req->io_start_time_ns = sched_clock(); 1464 preempt_enable(); 1465 } 1466 1467 static inline uint64_t rq_start_time_ns(struct request *req) 1468 { 1469 return req->start_time_ns; 1470 } 1471 1472 static inline uint64_t rq_io_start_time_ns(struct request *req) 1473 { 1474 return req->io_start_time_ns; 1475 } 1476 #else 1477 static inline void set_start_time_ns(struct request *req) {} 1478 static inline void set_io_start_time_ns(struct request *req) {} 1479 static inline uint64_t rq_start_time_ns(struct request *req) 1480 { 1481 return 0; 1482 } 1483 static inline uint64_t rq_io_start_time_ns(struct request *req) 1484 { 1485 return 0; 1486 } 1487 #endif 1488 1489 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1490 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1491 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1492 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1493 1494 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1495 1496 enum blk_integrity_flags { 1497 BLK_INTEGRITY_VERIFY = 1 << 0, 1498 BLK_INTEGRITY_GENERATE = 1 << 1, 1499 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2, 1500 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3, 1501 }; 1502 1503 struct blk_integrity_iter { 1504 void *prot_buf; 1505 void *data_buf; 1506 sector_t seed; 1507 unsigned int data_size; 1508 unsigned short interval; 1509 const char *disk_name; 1510 }; 1511 1512 typedef int (integrity_processing_fn) (struct blk_integrity_iter *); 1513 1514 struct blk_integrity_profile { 1515 integrity_processing_fn *generate_fn; 1516 integrity_processing_fn *verify_fn; 1517 const char *name; 1518 }; 1519 1520 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *); 1521 extern void blk_integrity_unregister(struct gendisk *); 1522 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1523 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1524 struct scatterlist *); 1525 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1526 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, 1527 struct request *); 1528 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, 1529 struct bio *); 1530 1531 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1532 { 1533 struct blk_integrity *bi = &disk->queue->integrity; 1534 1535 if (!bi->profile) 1536 return NULL; 1537 1538 return bi; 1539 } 1540 1541 static inline 1542 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1543 { 1544 return blk_get_integrity(bdev->bd_disk); 1545 } 1546 1547 static inline bool blk_integrity_rq(struct request *rq) 1548 { 1549 return rq->cmd_flags & REQ_INTEGRITY; 1550 } 1551 1552 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1553 unsigned int segs) 1554 { 1555 q->limits.max_integrity_segments = segs; 1556 } 1557 1558 static inline unsigned short 1559 queue_max_integrity_segments(struct request_queue *q) 1560 { 1561 return q->limits.max_integrity_segments; 1562 } 1563 1564 static inline bool integrity_req_gap_back_merge(struct request *req, 1565 struct bio *next) 1566 { 1567 struct bio_integrity_payload *bip = bio_integrity(req->bio); 1568 struct bio_integrity_payload *bip_next = bio_integrity(next); 1569 1570 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1571 bip_next->bip_vec[0].bv_offset); 1572 } 1573 1574 static inline bool integrity_req_gap_front_merge(struct request *req, 1575 struct bio *bio) 1576 { 1577 struct bio_integrity_payload *bip = bio_integrity(bio); 1578 struct bio_integrity_payload *bip_next = bio_integrity(req->bio); 1579 1580 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1581 bip_next->bip_vec[0].bv_offset); 1582 } 1583 1584 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1585 1586 struct bio; 1587 struct block_device; 1588 struct gendisk; 1589 struct blk_integrity; 1590 1591 static inline int blk_integrity_rq(struct request *rq) 1592 { 1593 return 0; 1594 } 1595 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1596 struct bio *b) 1597 { 1598 return 0; 1599 } 1600 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1601 struct bio *b, 1602 struct scatterlist *s) 1603 { 1604 return 0; 1605 } 1606 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1607 { 1608 return NULL; 1609 } 1610 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1611 { 1612 return NULL; 1613 } 1614 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1615 { 1616 return 0; 1617 } 1618 static inline void blk_integrity_register(struct gendisk *d, 1619 struct blk_integrity *b) 1620 { 1621 } 1622 static inline void blk_integrity_unregister(struct gendisk *d) 1623 { 1624 } 1625 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1626 unsigned int segs) 1627 { 1628 } 1629 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1630 { 1631 return 0; 1632 } 1633 static inline bool blk_integrity_merge_rq(struct request_queue *rq, 1634 struct request *r1, 1635 struct request *r2) 1636 { 1637 return true; 1638 } 1639 static inline bool blk_integrity_merge_bio(struct request_queue *rq, 1640 struct request *r, 1641 struct bio *b) 1642 { 1643 return true; 1644 } 1645 1646 static inline bool integrity_req_gap_back_merge(struct request *req, 1647 struct bio *next) 1648 { 1649 return false; 1650 } 1651 static inline bool integrity_req_gap_front_merge(struct request *req, 1652 struct bio *bio) 1653 { 1654 return false; 1655 } 1656 1657 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1658 1659 /** 1660 * struct blk_dax_ctl - control and output parameters for ->direct_access 1661 * @sector: (input) offset relative to a block_device 1662 * @addr: (output) kernel virtual address for @sector populated by driver 1663 * @pfn: (output) page frame number for @addr populated by driver 1664 * @size: (input) number of bytes requested 1665 */ 1666 struct blk_dax_ctl { 1667 sector_t sector; 1668 void *addr; 1669 long size; 1670 pfn_t pfn; 1671 }; 1672 1673 struct block_device_operations { 1674 int (*open) (struct block_device *, fmode_t); 1675 void (*release) (struct gendisk *, fmode_t); 1676 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw); 1677 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1678 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1679 long (*direct_access)(struct block_device *, sector_t, void **, pfn_t *, 1680 long); 1681 unsigned int (*check_events) (struct gendisk *disk, 1682 unsigned int clearing); 1683 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1684 int (*media_changed) (struct gendisk *); 1685 void (*unlock_native_capacity) (struct gendisk *); 1686 int (*revalidate_disk) (struct gendisk *); 1687 int (*getgeo)(struct block_device *, struct hd_geometry *); 1688 /* this callback is with swap_lock and sometimes page table lock held */ 1689 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1690 struct module *owner; 1691 const struct pr_ops *pr_ops; 1692 }; 1693 1694 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1695 unsigned long); 1696 extern int bdev_read_page(struct block_device *, sector_t, struct page *); 1697 extern int bdev_write_page(struct block_device *, sector_t, struct page *, 1698 struct writeback_control *); 1699 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *); 1700 extern int bdev_dax_supported(struct super_block *, int); 1701 extern bool bdev_dax_capable(struct block_device *); 1702 #else /* CONFIG_BLOCK */ 1703 1704 struct block_device; 1705 1706 /* 1707 * stubs for when the block layer is configured out 1708 */ 1709 #define buffer_heads_over_limit 0 1710 1711 static inline long nr_blockdev_pages(void) 1712 { 1713 return 0; 1714 } 1715 1716 struct blk_plug { 1717 }; 1718 1719 static inline void blk_start_plug(struct blk_plug *plug) 1720 { 1721 } 1722 1723 static inline void blk_finish_plug(struct blk_plug *plug) 1724 { 1725 } 1726 1727 static inline void blk_flush_plug(struct task_struct *task) 1728 { 1729 } 1730 1731 static inline void blk_schedule_flush_plug(struct task_struct *task) 1732 { 1733 } 1734 1735 1736 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1737 { 1738 return false; 1739 } 1740 1741 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, 1742 sector_t *error_sector) 1743 { 1744 return 0; 1745 } 1746 1747 #endif /* CONFIG_BLOCK */ 1748 1749 #endif 1750