1 #ifndef _LINUX_BLKDEV_H 2 #define _LINUX_BLKDEV_H 3 4 #ifdef CONFIG_BLOCK 5 6 #include <linux/sched.h> 7 #include <linux/major.h> 8 #include <linux/genhd.h> 9 #include <linux/list.h> 10 #include <linux/timer.h> 11 #include <linux/workqueue.h> 12 #include <linux/pagemap.h> 13 #include <linux/backing-dev.h> 14 #include <linux/wait.h> 15 #include <linux/mempool.h> 16 #include <linux/bio.h> 17 #include <linux/stringify.h> 18 #include <linux/gfp.h> 19 #include <linux/bsg.h> 20 #include <linux/smp.h> 21 22 #include <asm/scatterlist.h> 23 24 struct module; 25 struct scsi_ioctl_command; 26 27 struct request_queue; 28 struct elevator_queue; 29 struct request_pm_state; 30 struct blk_trace; 31 struct request; 32 struct sg_io_hdr; 33 struct bsg_job; 34 35 #define BLKDEV_MIN_RQ 4 36 #define BLKDEV_MAX_RQ 128 /* Default maximum */ 37 38 struct request; 39 typedef void (rq_end_io_fn)(struct request *, int); 40 41 struct request_list { 42 /* 43 * count[], starved[], and wait[] are indexed by 44 * BLK_RW_SYNC/BLK_RW_ASYNC 45 */ 46 int count[2]; 47 int starved[2]; 48 int elvpriv; 49 mempool_t *rq_pool; 50 wait_queue_head_t wait[2]; 51 }; 52 53 /* 54 * request command types 55 */ 56 enum rq_cmd_type_bits { 57 REQ_TYPE_FS = 1, /* fs request */ 58 REQ_TYPE_BLOCK_PC, /* scsi command */ 59 REQ_TYPE_SENSE, /* sense request */ 60 REQ_TYPE_PM_SUSPEND, /* suspend request */ 61 REQ_TYPE_PM_RESUME, /* resume request */ 62 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */ 63 REQ_TYPE_SPECIAL, /* driver defined type */ 64 /* 65 * for ATA/ATAPI devices. this really doesn't belong here, ide should 66 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver 67 * private REQ_LB opcodes to differentiate what type of request this is 68 */ 69 REQ_TYPE_ATA_TASKFILE, 70 REQ_TYPE_ATA_PC, 71 }; 72 73 #define BLK_MAX_CDB 16 74 75 /* 76 * try to put the fields that are referenced together in the same cacheline. 77 * if you modify this structure, be sure to check block/blk-core.c:blk_rq_init() 78 * as well! 79 */ 80 struct request { 81 struct list_head queuelist; 82 struct call_single_data csd; 83 84 struct request_queue *q; 85 86 unsigned int cmd_flags; 87 enum rq_cmd_type_bits cmd_type; 88 unsigned long atomic_flags; 89 90 int cpu; 91 92 /* the following two fields are internal, NEVER access directly */ 93 unsigned int __data_len; /* total data len */ 94 sector_t __sector; /* sector cursor */ 95 96 struct bio *bio; 97 struct bio *biotail; 98 99 struct hlist_node hash; /* merge hash */ 100 /* 101 * The rb_node is only used inside the io scheduler, requests 102 * are pruned when moved to the dispatch queue. So let the 103 * completion_data share space with the rb_node. 104 */ 105 union { 106 struct rb_node rb_node; /* sort/lookup */ 107 void *completion_data; 108 }; 109 110 /* 111 * Three pointers are available for the IO schedulers, if they need 112 * more they have to dynamically allocate it. Flush requests are 113 * never put on the IO scheduler. So let the flush fields share 114 * space with the elevator data. 115 */ 116 union { 117 struct { 118 struct io_cq *icq; 119 void *priv[2]; 120 } elv; 121 122 struct { 123 unsigned int seq; 124 struct list_head list; 125 rq_end_io_fn *saved_end_io; 126 } flush; 127 }; 128 129 struct gendisk *rq_disk; 130 struct hd_struct *part; 131 unsigned long start_time; 132 #ifdef CONFIG_BLK_CGROUP 133 unsigned long long start_time_ns; 134 unsigned long long io_start_time_ns; /* when passed to hardware */ 135 #endif 136 /* Number of scatter-gather DMA addr+len pairs after 137 * physical address coalescing is performed. 138 */ 139 unsigned short nr_phys_segments; 140 #if defined(CONFIG_BLK_DEV_INTEGRITY) 141 unsigned short nr_integrity_segments; 142 #endif 143 144 unsigned short ioprio; 145 146 int ref_count; 147 148 void *special; /* opaque pointer available for LLD use */ 149 char *buffer; /* kaddr of the current segment if available */ 150 151 int tag; 152 int errors; 153 154 /* 155 * when request is used as a packet command carrier 156 */ 157 unsigned char __cmd[BLK_MAX_CDB]; 158 unsigned char *cmd; 159 unsigned short cmd_len; 160 161 unsigned int extra_len; /* length of alignment and padding */ 162 unsigned int sense_len; 163 unsigned int resid_len; /* residual count */ 164 void *sense; 165 166 unsigned long deadline; 167 struct list_head timeout_list; 168 unsigned int timeout; 169 int retries; 170 171 /* 172 * completion callback. 173 */ 174 rq_end_io_fn *end_io; 175 void *end_io_data; 176 177 /* for bidi */ 178 struct request *next_rq; 179 }; 180 181 static inline unsigned short req_get_ioprio(struct request *req) 182 { 183 return req->ioprio; 184 } 185 186 /* 187 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME 188 * requests. Some step values could eventually be made generic. 189 */ 190 struct request_pm_state 191 { 192 /* PM state machine step value, currently driver specific */ 193 int pm_step; 194 /* requested PM state value (S1, S2, S3, S4, ...) */ 195 u32 pm_state; 196 void* data; /* for driver use */ 197 }; 198 199 #include <linux/elevator.h> 200 201 typedef void (request_fn_proc) (struct request_queue *q); 202 typedef void (make_request_fn) (struct request_queue *q, struct bio *bio); 203 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 204 typedef void (unprep_rq_fn) (struct request_queue *, struct request *); 205 206 struct bio_vec; 207 struct bvec_merge_data { 208 struct block_device *bi_bdev; 209 sector_t bi_sector; 210 unsigned bi_size; 211 unsigned long bi_rw; 212 }; 213 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *, 214 struct bio_vec *); 215 typedef void (softirq_done_fn)(struct request *); 216 typedef int (dma_drain_needed_fn)(struct request *); 217 typedef int (lld_busy_fn) (struct request_queue *q); 218 typedef int (bsg_job_fn) (struct bsg_job *); 219 220 enum blk_eh_timer_return { 221 BLK_EH_NOT_HANDLED, 222 BLK_EH_HANDLED, 223 BLK_EH_RESET_TIMER, 224 }; 225 226 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 227 228 enum blk_queue_state { 229 Queue_down, 230 Queue_up, 231 }; 232 233 struct blk_queue_tag { 234 struct request **tag_index; /* map of busy tags */ 235 unsigned long *tag_map; /* bit map of free/busy tags */ 236 int busy; /* current depth */ 237 int max_depth; /* what we will send to device */ 238 int real_max_depth; /* what the array can hold */ 239 atomic_t refcnt; /* map can be shared */ 240 }; 241 242 #define BLK_SCSI_MAX_CMDS (256) 243 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 244 245 struct queue_limits { 246 unsigned long bounce_pfn; 247 unsigned long seg_boundary_mask; 248 249 unsigned int max_hw_sectors; 250 unsigned int max_sectors; 251 unsigned int max_segment_size; 252 unsigned int physical_block_size; 253 unsigned int alignment_offset; 254 unsigned int io_min; 255 unsigned int io_opt; 256 unsigned int max_discard_sectors; 257 unsigned int discard_granularity; 258 unsigned int discard_alignment; 259 260 unsigned short logical_block_size; 261 unsigned short max_segments; 262 unsigned short max_integrity_segments; 263 264 unsigned char misaligned; 265 unsigned char discard_misaligned; 266 unsigned char cluster; 267 unsigned char discard_zeroes_data; 268 }; 269 270 struct request_queue { 271 /* 272 * Together with queue_head for cacheline sharing 273 */ 274 struct list_head queue_head; 275 struct request *last_merge; 276 struct elevator_queue *elevator; 277 278 /* 279 * the queue request freelist, one for reads and one for writes 280 */ 281 struct request_list rq; 282 283 request_fn_proc *request_fn; 284 make_request_fn *make_request_fn; 285 prep_rq_fn *prep_rq_fn; 286 unprep_rq_fn *unprep_rq_fn; 287 merge_bvec_fn *merge_bvec_fn; 288 softirq_done_fn *softirq_done_fn; 289 rq_timed_out_fn *rq_timed_out_fn; 290 dma_drain_needed_fn *dma_drain_needed; 291 lld_busy_fn *lld_busy_fn; 292 293 /* 294 * Dispatch queue sorting 295 */ 296 sector_t end_sector; 297 struct request *boundary_rq; 298 299 /* 300 * Delayed queue handling 301 */ 302 struct delayed_work delay_work; 303 304 struct backing_dev_info backing_dev_info; 305 306 /* 307 * The queue owner gets to use this for whatever they like. 308 * ll_rw_blk doesn't touch it. 309 */ 310 void *queuedata; 311 312 /* 313 * various queue flags, see QUEUE_* below 314 */ 315 unsigned long queue_flags; 316 317 /* 318 * ida allocated id for this queue. Used to index queues from 319 * ioctx. 320 */ 321 int id; 322 323 /* 324 * queue needs bounce pages for pages above this limit 325 */ 326 gfp_t bounce_gfp; 327 328 /* 329 * protects queue structures from reentrancy. ->__queue_lock should 330 * _never_ be used directly, it is queue private. always use 331 * ->queue_lock. 332 */ 333 spinlock_t __queue_lock; 334 spinlock_t *queue_lock; 335 336 /* 337 * queue kobject 338 */ 339 struct kobject kobj; 340 341 /* 342 * queue settings 343 */ 344 unsigned long nr_requests; /* Max # of requests */ 345 unsigned int nr_congestion_on; 346 unsigned int nr_congestion_off; 347 unsigned int nr_batching; 348 349 unsigned int dma_drain_size; 350 void *dma_drain_buffer; 351 unsigned int dma_pad_mask; 352 unsigned int dma_alignment; 353 354 struct blk_queue_tag *queue_tags; 355 struct list_head tag_busy_list; 356 357 unsigned int nr_sorted; 358 unsigned int in_flight[2]; 359 360 unsigned int rq_timeout; 361 struct timer_list timeout; 362 struct list_head timeout_list; 363 364 struct list_head icq_list; 365 366 struct queue_limits limits; 367 368 /* 369 * sg stuff 370 */ 371 unsigned int sg_timeout; 372 unsigned int sg_reserved_size; 373 int node; 374 #ifdef CONFIG_BLK_DEV_IO_TRACE 375 struct blk_trace *blk_trace; 376 #endif 377 /* 378 * for flush operations 379 */ 380 unsigned int flush_flags; 381 unsigned int flush_not_queueable:1; 382 unsigned int flush_queue_delayed:1; 383 unsigned int flush_pending_idx:1; 384 unsigned int flush_running_idx:1; 385 unsigned long flush_pending_since; 386 struct list_head flush_queue[2]; 387 struct list_head flush_data_in_flight; 388 struct request flush_rq; 389 390 struct mutex sysfs_lock; 391 392 #if defined(CONFIG_BLK_DEV_BSG) 393 bsg_job_fn *bsg_job_fn; 394 int bsg_job_size; 395 struct bsg_class_device bsg_dev; 396 #endif 397 398 #ifdef CONFIG_BLK_DEV_THROTTLING 399 /* Throttle data */ 400 struct throtl_data *td; 401 #endif 402 }; 403 404 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 405 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 406 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 407 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 408 #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ 409 #define QUEUE_FLAG_ELVSWITCH 6 /* don't use elevator, just do FIFO */ 410 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ 411 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ 412 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ 413 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ 414 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ 415 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ 416 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 417 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ 418 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ 419 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ 420 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ 421 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */ 422 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ 423 424 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 425 (1 << QUEUE_FLAG_STACKABLE) | \ 426 (1 << QUEUE_FLAG_SAME_COMP) | \ 427 (1 << QUEUE_FLAG_ADD_RANDOM)) 428 429 static inline void queue_lockdep_assert_held(struct request_queue *q) 430 { 431 if (q->queue_lock) 432 lockdep_assert_held(q->queue_lock); 433 } 434 435 static inline void queue_flag_set_unlocked(unsigned int flag, 436 struct request_queue *q) 437 { 438 __set_bit(flag, &q->queue_flags); 439 } 440 441 static inline int queue_flag_test_and_clear(unsigned int flag, 442 struct request_queue *q) 443 { 444 queue_lockdep_assert_held(q); 445 446 if (test_bit(flag, &q->queue_flags)) { 447 __clear_bit(flag, &q->queue_flags); 448 return 1; 449 } 450 451 return 0; 452 } 453 454 static inline int queue_flag_test_and_set(unsigned int flag, 455 struct request_queue *q) 456 { 457 queue_lockdep_assert_held(q); 458 459 if (!test_bit(flag, &q->queue_flags)) { 460 __set_bit(flag, &q->queue_flags); 461 return 0; 462 } 463 464 return 1; 465 } 466 467 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 468 { 469 queue_lockdep_assert_held(q); 470 __set_bit(flag, &q->queue_flags); 471 } 472 473 static inline void queue_flag_clear_unlocked(unsigned int flag, 474 struct request_queue *q) 475 { 476 __clear_bit(flag, &q->queue_flags); 477 } 478 479 static inline int queue_in_flight(struct request_queue *q) 480 { 481 return q->in_flight[0] + q->in_flight[1]; 482 } 483 484 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 485 { 486 queue_lockdep_assert_held(q); 487 __clear_bit(flag, &q->queue_flags); 488 } 489 490 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 491 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 492 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 493 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 494 #define blk_queue_noxmerges(q) \ 495 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 496 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 497 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 498 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 499 #define blk_queue_stackable(q) \ 500 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 501 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 502 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \ 503 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags)) 504 505 #define blk_noretry_request(rq) \ 506 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 507 REQ_FAILFAST_DRIVER)) 508 509 #define blk_account_rq(rq) \ 510 (((rq)->cmd_flags & REQ_STARTED) && \ 511 ((rq)->cmd_type == REQ_TYPE_FS || \ 512 ((rq)->cmd_flags & REQ_DISCARD))) 513 514 #define blk_pm_request(rq) \ 515 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \ 516 (rq)->cmd_type == REQ_TYPE_PM_RESUME) 517 518 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 519 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 520 /* rq->queuelist of dequeued request must be list_empty() */ 521 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 522 523 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 524 525 #define rq_data_dir(rq) ((rq)->cmd_flags & 1) 526 527 static inline unsigned int blk_queue_cluster(struct request_queue *q) 528 { 529 return q->limits.cluster; 530 } 531 532 /* 533 * We regard a request as sync, if either a read or a sync write 534 */ 535 static inline bool rw_is_sync(unsigned int rw_flags) 536 { 537 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC); 538 } 539 540 static inline bool rq_is_sync(struct request *rq) 541 { 542 return rw_is_sync(rq->cmd_flags); 543 } 544 545 static inline int blk_queue_full(struct request_queue *q, int sync) 546 { 547 if (sync) 548 return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags); 549 return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags); 550 } 551 552 static inline void blk_set_queue_full(struct request_queue *q, int sync) 553 { 554 if (sync) 555 queue_flag_set(QUEUE_FLAG_SYNCFULL, q); 556 else 557 queue_flag_set(QUEUE_FLAG_ASYNCFULL, q); 558 } 559 560 static inline void blk_clear_queue_full(struct request_queue *q, int sync) 561 { 562 if (sync) 563 queue_flag_clear(QUEUE_FLAG_SYNCFULL, q); 564 else 565 queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q); 566 } 567 568 569 /* 570 * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may 571 * it already be started by driver. 572 */ 573 #define RQ_NOMERGE_FLAGS \ 574 (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA) 575 #define rq_mergeable(rq) \ 576 (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \ 577 (((rq)->cmd_flags & REQ_DISCARD) || \ 578 (rq)->cmd_type == REQ_TYPE_FS)) 579 580 /* 581 * q->prep_rq_fn return values 582 */ 583 #define BLKPREP_OK 0 /* serve it */ 584 #define BLKPREP_KILL 1 /* fatal error, kill */ 585 #define BLKPREP_DEFER 2 /* leave on queue */ 586 587 extern unsigned long blk_max_low_pfn, blk_max_pfn; 588 589 /* 590 * standard bounce addresses: 591 * 592 * BLK_BOUNCE_HIGH : bounce all highmem pages 593 * BLK_BOUNCE_ANY : don't bounce anything 594 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 595 */ 596 597 #if BITS_PER_LONG == 32 598 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 599 #else 600 #define BLK_BOUNCE_HIGH -1ULL 601 #endif 602 #define BLK_BOUNCE_ANY (-1ULL) 603 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 604 605 /* 606 * default timeout for SG_IO if none specified 607 */ 608 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 609 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 610 611 #ifdef CONFIG_BOUNCE 612 extern int init_emergency_isa_pool(void); 613 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 614 #else 615 static inline int init_emergency_isa_pool(void) 616 { 617 return 0; 618 } 619 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 620 { 621 } 622 #endif /* CONFIG_MMU */ 623 624 struct rq_map_data { 625 struct page **pages; 626 int page_order; 627 int nr_entries; 628 unsigned long offset; 629 int null_mapped; 630 int from_user; 631 }; 632 633 struct req_iterator { 634 int i; 635 struct bio *bio; 636 }; 637 638 /* This should not be used directly - use rq_for_each_segment */ 639 #define for_each_bio(_bio) \ 640 for (; _bio; _bio = _bio->bi_next) 641 #define __rq_for_each_bio(_bio, rq) \ 642 if ((rq->bio)) \ 643 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 644 645 #define rq_for_each_segment(bvl, _rq, _iter) \ 646 __rq_for_each_bio(_iter.bio, _rq) \ 647 bio_for_each_segment(bvl, _iter.bio, _iter.i) 648 649 #define rq_iter_last(rq, _iter) \ 650 (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1) 651 652 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 653 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 654 #endif 655 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 656 extern void rq_flush_dcache_pages(struct request *rq); 657 #else 658 static inline void rq_flush_dcache_pages(struct request *rq) 659 { 660 } 661 #endif 662 663 extern int blk_register_queue(struct gendisk *disk); 664 extern void blk_unregister_queue(struct gendisk *disk); 665 extern void generic_make_request(struct bio *bio); 666 extern void blk_rq_init(struct request_queue *q, struct request *rq); 667 extern void blk_put_request(struct request *); 668 extern void __blk_put_request(struct request_queue *, struct request *); 669 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 670 extern struct request *blk_make_request(struct request_queue *, struct bio *, 671 gfp_t); 672 extern void blk_requeue_request(struct request_queue *, struct request *); 673 extern void blk_add_request_payload(struct request *rq, struct page *page, 674 unsigned int len); 675 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); 676 extern int blk_lld_busy(struct request_queue *q); 677 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 678 struct bio_set *bs, gfp_t gfp_mask, 679 int (*bio_ctr)(struct bio *, struct bio *, void *), 680 void *data); 681 extern void blk_rq_unprep_clone(struct request *rq); 682 extern int blk_insert_cloned_request(struct request_queue *q, 683 struct request *rq); 684 extern void blk_delay_queue(struct request_queue *, unsigned long); 685 extern void blk_recount_segments(struct request_queue *, struct bio *); 686 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 687 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 688 unsigned int, void __user *); 689 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 690 unsigned int, void __user *); 691 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 692 struct scsi_ioctl_command __user *); 693 694 extern void blk_queue_bio(struct request_queue *q, struct bio *bio); 695 696 /* 697 * A queue has just exitted congestion. Note this in the global counter of 698 * congested queues, and wake up anyone who was waiting for requests to be 699 * put back. 700 */ 701 static inline void blk_clear_queue_congested(struct request_queue *q, int sync) 702 { 703 clear_bdi_congested(&q->backing_dev_info, sync); 704 } 705 706 /* 707 * A queue has just entered congestion. Flag that in the queue's VM-visible 708 * state flags and increment the global gounter of congested queues. 709 */ 710 static inline void blk_set_queue_congested(struct request_queue *q, int sync) 711 { 712 set_bdi_congested(&q->backing_dev_info, sync); 713 } 714 715 extern void blk_start_queue(struct request_queue *q); 716 extern void blk_stop_queue(struct request_queue *q); 717 extern void blk_sync_queue(struct request_queue *q); 718 extern void __blk_stop_queue(struct request_queue *q); 719 extern void __blk_run_queue(struct request_queue *q); 720 extern void blk_run_queue(struct request_queue *); 721 extern void blk_run_queue_async(struct request_queue *q); 722 extern int blk_rq_map_user(struct request_queue *, struct request *, 723 struct rq_map_data *, void __user *, unsigned long, 724 gfp_t); 725 extern int blk_rq_unmap_user(struct bio *); 726 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 727 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 728 struct rq_map_data *, struct sg_iovec *, int, 729 unsigned int, gfp_t); 730 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 731 struct request *, int); 732 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 733 struct request *, int, rq_end_io_fn *); 734 735 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 736 { 737 return bdev->bd_disk->queue; 738 } 739 740 /* 741 * blk_rq_pos() : the current sector 742 * blk_rq_bytes() : bytes left in the entire request 743 * blk_rq_cur_bytes() : bytes left in the current segment 744 * blk_rq_err_bytes() : bytes left till the next error boundary 745 * blk_rq_sectors() : sectors left in the entire request 746 * blk_rq_cur_sectors() : sectors left in the current segment 747 */ 748 static inline sector_t blk_rq_pos(const struct request *rq) 749 { 750 return rq->__sector; 751 } 752 753 static inline unsigned int blk_rq_bytes(const struct request *rq) 754 { 755 return rq->__data_len; 756 } 757 758 static inline int blk_rq_cur_bytes(const struct request *rq) 759 { 760 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 761 } 762 763 extern unsigned int blk_rq_err_bytes(const struct request *rq); 764 765 static inline unsigned int blk_rq_sectors(const struct request *rq) 766 { 767 return blk_rq_bytes(rq) >> 9; 768 } 769 770 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 771 { 772 return blk_rq_cur_bytes(rq) >> 9; 773 } 774 775 /* 776 * Request issue related functions. 777 */ 778 extern struct request *blk_peek_request(struct request_queue *q); 779 extern void blk_start_request(struct request *rq); 780 extern struct request *blk_fetch_request(struct request_queue *q); 781 782 /* 783 * Request completion related functions. 784 * 785 * blk_update_request() completes given number of bytes and updates 786 * the request without completing it. 787 * 788 * blk_end_request() and friends. __blk_end_request() must be called 789 * with the request queue spinlock acquired. 790 * 791 * Several drivers define their own end_request and call 792 * blk_end_request() for parts of the original function. 793 * This prevents code duplication in drivers. 794 */ 795 extern bool blk_update_request(struct request *rq, int error, 796 unsigned int nr_bytes); 797 extern bool blk_end_request(struct request *rq, int error, 798 unsigned int nr_bytes); 799 extern void blk_end_request_all(struct request *rq, int error); 800 extern bool blk_end_request_cur(struct request *rq, int error); 801 extern bool blk_end_request_err(struct request *rq, int error); 802 extern bool __blk_end_request(struct request *rq, int error, 803 unsigned int nr_bytes); 804 extern void __blk_end_request_all(struct request *rq, int error); 805 extern bool __blk_end_request_cur(struct request *rq, int error); 806 extern bool __blk_end_request_err(struct request *rq, int error); 807 808 extern void blk_complete_request(struct request *); 809 extern void __blk_complete_request(struct request *); 810 extern void blk_abort_request(struct request *); 811 extern void blk_abort_queue(struct request_queue *); 812 extern void blk_unprep_request(struct request *); 813 814 /* 815 * Access functions for manipulating queue properties 816 */ 817 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 818 spinlock_t *lock, int node_id); 819 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 820 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 821 request_fn_proc *, spinlock_t *); 822 extern void blk_cleanup_queue(struct request_queue *); 823 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 824 extern void blk_queue_bounce_limit(struct request_queue *, u64); 825 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int); 826 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 827 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 828 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 829 extern void blk_queue_max_discard_sectors(struct request_queue *q, 830 unsigned int max_discard_sectors); 831 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 832 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 833 extern void blk_queue_alignment_offset(struct request_queue *q, 834 unsigned int alignment); 835 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 836 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 837 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 838 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 839 extern void blk_set_default_limits(struct queue_limits *lim); 840 extern void blk_set_stacking_limits(struct queue_limits *lim); 841 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 842 sector_t offset); 843 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 844 sector_t offset); 845 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 846 sector_t offset); 847 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 848 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 849 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 850 extern int blk_queue_dma_drain(struct request_queue *q, 851 dma_drain_needed_fn *dma_drain_needed, 852 void *buf, unsigned int size); 853 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 854 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 855 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 856 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 857 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); 858 extern void blk_queue_dma_alignment(struct request_queue *, int); 859 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 860 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 861 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 862 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 863 extern void blk_queue_flush(struct request_queue *q, unsigned int flush); 864 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 865 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 866 867 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 868 extern void blk_dump_rq_flags(struct request *, char *); 869 extern long nr_blockdev_pages(void); 870 871 bool __must_check blk_get_queue(struct request_queue *); 872 struct request_queue *blk_alloc_queue(gfp_t); 873 struct request_queue *blk_alloc_queue_node(gfp_t, int); 874 extern void blk_put_queue(struct request_queue *); 875 876 /* 877 * blk_plug permits building a queue of related requests by holding the I/O 878 * fragments for a short period. This allows merging of sequential requests 879 * into single larger request. As the requests are moved from a per-task list to 880 * the device's request_queue in a batch, this results in improved scalability 881 * as the lock contention for request_queue lock is reduced. 882 * 883 * It is ok not to disable preemption when adding the request to the plug list 884 * or when attempting a merge, because blk_schedule_flush_list() will only flush 885 * the plug list when the task sleeps by itself. For details, please see 886 * schedule() where blk_schedule_flush_plug() is called. 887 */ 888 struct blk_plug { 889 unsigned long magic; /* detect uninitialized use-cases */ 890 struct list_head list; /* requests */ 891 struct list_head cb_list; /* md requires an unplug callback */ 892 unsigned int should_sort; /* list to be sorted before flushing? */ 893 }; 894 #define BLK_MAX_REQUEST_COUNT 16 895 896 struct blk_plug_cb { 897 struct list_head list; 898 void (*callback)(struct blk_plug_cb *); 899 }; 900 901 extern void blk_start_plug(struct blk_plug *); 902 extern void blk_finish_plug(struct blk_plug *); 903 extern void blk_flush_plug_list(struct blk_plug *, bool); 904 905 static inline void blk_flush_plug(struct task_struct *tsk) 906 { 907 struct blk_plug *plug = tsk->plug; 908 909 if (plug) 910 blk_flush_plug_list(plug, false); 911 } 912 913 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 914 { 915 struct blk_plug *plug = tsk->plug; 916 917 if (plug) 918 blk_flush_plug_list(plug, true); 919 } 920 921 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 922 { 923 struct blk_plug *plug = tsk->plug; 924 925 return plug && (!list_empty(&plug->list) || !list_empty(&plug->cb_list)); 926 } 927 928 /* 929 * tag stuff 930 */ 931 #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED) 932 extern int blk_queue_start_tag(struct request_queue *, struct request *); 933 extern struct request *blk_queue_find_tag(struct request_queue *, int); 934 extern void blk_queue_end_tag(struct request_queue *, struct request *); 935 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *); 936 extern void blk_queue_free_tags(struct request_queue *); 937 extern int blk_queue_resize_tags(struct request_queue *, int); 938 extern void blk_queue_invalidate_tags(struct request_queue *); 939 extern struct blk_queue_tag *blk_init_tags(int); 940 extern void blk_free_tags(struct blk_queue_tag *); 941 942 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 943 int tag) 944 { 945 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 946 return NULL; 947 return bqt->tag_index[tag]; 948 } 949 950 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */ 951 952 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 953 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 954 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 955 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 956 sector_t nr_sects, gfp_t gfp_mask); 957 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 958 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 959 { 960 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 961 nr_blocks << (sb->s_blocksize_bits - 9), 962 gfp_mask, flags); 963 } 964 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 965 sector_t nr_blocks, gfp_t gfp_mask) 966 { 967 return blkdev_issue_zeroout(sb->s_bdev, 968 block << (sb->s_blocksize_bits - 9), 969 nr_blocks << (sb->s_blocksize_bits - 9), 970 gfp_mask); 971 } 972 973 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 974 975 enum blk_default_limits { 976 BLK_MAX_SEGMENTS = 128, 977 BLK_SAFE_MAX_SECTORS = 255, 978 BLK_DEF_MAX_SECTORS = 1024, 979 BLK_MAX_SEGMENT_SIZE = 65536, 980 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 981 }; 982 983 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 984 985 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 986 { 987 return q->limits.bounce_pfn; 988 } 989 990 static inline unsigned long queue_segment_boundary(struct request_queue *q) 991 { 992 return q->limits.seg_boundary_mask; 993 } 994 995 static inline unsigned int queue_max_sectors(struct request_queue *q) 996 { 997 return q->limits.max_sectors; 998 } 999 1000 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1001 { 1002 return q->limits.max_hw_sectors; 1003 } 1004 1005 static inline unsigned short queue_max_segments(struct request_queue *q) 1006 { 1007 return q->limits.max_segments; 1008 } 1009 1010 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1011 { 1012 return q->limits.max_segment_size; 1013 } 1014 1015 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1016 { 1017 int retval = 512; 1018 1019 if (q && q->limits.logical_block_size) 1020 retval = q->limits.logical_block_size; 1021 1022 return retval; 1023 } 1024 1025 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1026 { 1027 return queue_logical_block_size(bdev_get_queue(bdev)); 1028 } 1029 1030 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1031 { 1032 return q->limits.physical_block_size; 1033 } 1034 1035 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1036 { 1037 return queue_physical_block_size(bdev_get_queue(bdev)); 1038 } 1039 1040 static inline unsigned int queue_io_min(struct request_queue *q) 1041 { 1042 return q->limits.io_min; 1043 } 1044 1045 static inline int bdev_io_min(struct block_device *bdev) 1046 { 1047 return queue_io_min(bdev_get_queue(bdev)); 1048 } 1049 1050 static inline unsigned int queue_io_opt(struct request_queue *q) 1051 { 1052 return q->limits.io_opt; 1053 } 1054 1055 static inline int bdev_io_opt(struct block_device *bdev) 1056 { 1057 return queue_io_opt(bdev_get_queue(bdev)); 1058 } 1059 1060 static inline int queue_alignment_offset(struct request_queue *q) 1061 { 1062 if (q->limits.misaligned) 1063 return -1; 1064 1065 return q->limits.alignment_offset; 1066 } 1067 1068 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1069 { 1070 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1071 unsigned int alignment = (sector << 9) & (granularity - 1); 1072 1073 return (granularity + lim->alignment_offset - alignment) 1074 & (granularity - 1); 1075 } 1076 1077 static inline int bdev_alignment_offset(struct block_device *bdev) 1078 { 1079 struct request_queue *q = bdev_get_queue(bdev); 1080 1081 if (q->limits.misaligned) 1082 return -1; 1083 1084 if (bdev != bdev->bd_contains) 1085 return bdev->bd_part->alignment_offset; 1086 1087 return q->limits.alignment_offset; 1088 } 1089 1090 static inline int queue_discard_alignment(struct request_queue *q) 1091 { 1092 if (q->limits.discard_misaligned) 1093 return -1; 1094 1095 return q->limits.discard_alignment; 1096 } 1097 1098 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1099 { 1100 unsigned int alignment = (sector << 9) & (lim->discard_granularity - 1); 1101 1102 if (!lim->max_discard_sectors) 1103 return 0; 1104 1105 return (lim->discard_granularity + lim->discard_alignment - alignment) 1106 & (lim->discard_granularity - 1); 1107 } 1108 1109 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1110 { 1111 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) 1112 return 1; 1113 1114 return 0; 1115 } 1116 1117 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1118 { 1119 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1120 } 1121 1122 static inline int queue_dma_alignment(struct request_queue *q) 1123 { 1124 return q ? q->dma_alignment : 511; 1125 } 1126 1127 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1128 unsigned int len) 1129 { 1130 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1131 return !(addr & alignment) && !(len & alignment); 1132 } 1133 1134 /* assumes size > 256 */ 1135 static inline unsigned int blksize_bits(unsigned int size) 1136 { 1137 unsigned int bits = 8; 1138 do { 1139 bits++; 1140 size >>= 1; 1141 } while (size > 256); 1142 return bits; 1143 } 1144 1145 static inline unsigned int block_size(struct block_device *bdev) 1146 { 1147 return bdev->bd_block_size; 1148 } 1149 1150 static inline bool queue_flush_queueable(struct request_queue *q) 1151 { 1152 return !q->flush_not_queueable; 1153 } 1154 1155 typedef struct {struct page *v;} Sector; 1156 1157 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1158 1159 static inline void put_dev_sector(Sector p) 1160 { 1161 page_cache_release(p.v); 1162 } 1163 1164 struct work_struct; 1165 int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); 1166 1167 #ifdef CONFIG_BLK_CGROUP 1168 /* 1169 * This should not be using sched_clock(). A real patch is in progress 1170 * to fix this up, until that is in place we need to disable preemption 1171 * around sched_clock() in this function and set_io_start_time_ns(). 1172 */ 1173 static inline void set_start_time_ns(struct request *req) 1174 { 1175 preempt_disable(); 1176 req->start_time_ns = sched_clock(); 1177 preempt_enable(); 1178 } 1179 1180 static inline void set_io_start_time_ns(struct request *req) 1181 { 1182 preempt_disable(); 1183 req->io_start_time_ns = sched_clock(); 1184 preempt_enable(); 1185 } 1186 1187 static inline uint64_t rq_start_time_ns(struct request *req) 1188 { 1189 return req->start_time_ns; 1190 } 1191 1192 static inline uint64_t rq_io_start_time_ns(struct request *req) 1193 { 1194 return req->io_start_time_ns; 1195 } 1196 #else 1197 static inline void set_start_time_ns(struct request *req) {} 1198 static inline void set_io_start_time_ns(struct request *req) {} 1199 static inline uint64_t rq_start_time_ns(struct request *req) 1200 { 1201 return 0; 1202 } 1203 static inline uint64_t rq_io_start_time_ns(struct request *req) 1204 { 1205 return 0; 1206 } 1207 #endif 1208 1209 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1210 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1211 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1212 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1213 1214 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1215 1216 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */ 1217 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */ 1218 1219 struct blk_integrity_exchg { 1220 void *prot_buf; 1221 void *data_buf; 1222 sector_t sector; 1223 unsigned int data_size; 1224 unsigned short sector_size; 1225 const char *disk_name; 1226 }; 1227 1228 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *); 1229 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *); 1230 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int); 1231 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int); 1232 1233 struct blk_integrity { 1234 integrity_gen_fn *generate_fn; 1235 integrity_vrfy_fn *verify_fn; 1236 integrity_set_tag_fn *set_tag_fn; 1237 integrity_get_tag_fn *get_tag_fn; 1238 1239 unsigned short flags; 1240 unsigned short tuple_size; 1241 unsigned short sector_size; 1242 unsigned short tag_size; 1243 1244 const char *name; 1245 1246 struct kobject kobj; 1247 }; 1248 1249 extern bool blk_integrity_is_initialized(struct gendisk *); 1250 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); 1251 extern void blk_integrity_unregister(struct gendisk *); 1252 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1253 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1254 struct scatterlist *); 1255 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1256 extern int blk_integrity_merge_rq(struct request_queue *, struct request *, 1257 struct request *); 1258 extern int blk_integrity_merge_bio(struct request_queue *, struct request *, 1259 struct bio *); 1260 1261 static inline 1262 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1263 { 1264 return bdev->bd_disk->integrity; 1265 } 1266 1267 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1268 { 1269 return disk->integrity; 1270 } 1271 1272 static inline int blk_integrity_rq(struct request *rq) 1273 { 1274 if (rq->bio == NULL) 1275 return 0; 1276 1277 return bio_integrity(rq->bio); 1278 } 1279 1280 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1281 unsigned int segs) 1282 { 1283 q->limits.max_integrity_segments = segs; 1284 } 1285 1286 static inline unsigned short 1287 queue_max_integrity_segments(struct request_queue *q) 1288 { 1289 return q->limits.max_integrity_segments; 1290 } 1291 1292 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1293 1294 struct bio; 1295 struct block_device; 1296 struct gendisk; 1297 struct blk_integrity; 1298 1299 static inline int blk_integrity_rq(struct request *rq) 1300 { 1301 return 0; 1302 } 1303 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1304 struct bio *b) 1305 { 1306 return 0; 1307 } 1308 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1309 struct bio *b, 1310 struct scatterlist *s) 1311 { 1312 return 0; 1313 } 1314 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1315 { 1316 return 0; 1317 } 1318 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1319 { 1320 return NULL; 1321 } 1322 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1323 { 1324 return 0; 1325 } 1326 static inline int blk_integrity_register(struct gendisk *d, 1327 struct blk_integrity *b) 1328 { 1329 return 0; 1330 } 1331 static inline void blk_integrity_unregister(struct gendisk *d) 1332 { 1333 } 1334 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1335 unsigned int segs) 1336 { 1337 } 1338 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1339 { 1340 return 0; 1341 } 1342 static inline int blk_integrity_merge_rq(struct request_queue *rq, 1343 struct request *r1, 1344 struct request *r2) 1345 { 1346 return 0; 1347 } 1348 static inline int blk_integrity_merge_bio(struct request_queue *rq, 1349 struct request *r, 1350 struct bio *b) 1351 { 1352 return 0; 1353 } 1354 static inline bool blk_integrity_is_initialized(struct gendisk *g) 1355 { 1356 return 0; 1357 } 1358 1359 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1360 1361 struct block_device_operations { 1362 int (*open) (struct block_device *, fmode_t); 1363 int (*release) (struct gendisk *, fmode_t); 1364 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1365 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1366 int (*direct_access) (struct block_device *, sector_t, 1367 void **, unsigned long *); 1368 unsigned int (*check_events) (struct gendisk *disk, 1369 unsigned int clearing); 1370 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1371 int (*media_changed) (struct gendisk *); 1372 void (*unlock_native_capacity) (struct gendisk *); 1373 int (*revalidate_disk) (struct gendisk *); 1374 int (*getgeo)(struct block_device *, struct hd_geometry *); 1375 /* this callback is with swap_lock and sometimes page table lock held */ 1376 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1377 struct module *owner; 1378 }; 1379 1380 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1381 unsigned long); 1382 #else /* CONFIG_BLOCK */ 1383 /* 1384 * stubs for when the block layer is configured out 1385 */ 1386 #define buffer_heads_over_limit 0 1387 1388 static inline long nr_blockdev_pages(void) 1389 { 1390 return 0; 1391 } 1392 1393 struct blk_plug { 1394 }; 1395 1396 static inline void blk_start_plug(struct blk_plug *plug) 1397 { 1398 } 1399 1400 static inline void blk_finish_plug(struct blk_plug *plug) 1401 { 1402 } 1403 1404 static inline void blk_flush_plug(struct task_struct *task) 1405 { 1406 } 1407 1408 static inline void blk_schedule_flush_plug(struct task_struct *task) 1409 { 1410 } 1411 1412 1413 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1414 { 1415 return false; 1416 } 1417 1418 #endif /* CONFIG_BLOCK */ 1419 1420 #endif 1421