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 #ifdef CONFIG_LOCKDEP 403 int ioc_release_depth; 404 #endif 405 }; 406 407 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 408 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 409 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 410 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 411 #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ 412 #define QUEUE_FLAG_ELVSWITCH 6 /* don't use elevator, just do FIFO */ 413 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ 414 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ 415 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ 416 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ 417 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ 418 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ 419 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 420 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ 421 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ 422 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ 423 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ 424 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */ 425 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ 426 427 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 428 (1 << QUEUE_FLAG_STACKABLE) | \ 429 (1 << QUEUE_FLAG_SAME_COMP) | \ 430 (1 << QUEUE_FLAG_ADD_RANDOM)) 431 432 static inline int queue_is_locked(struct request_queue *q) 433 { 434 #ifdef CONFIG_SMP 435 spinlock_t *lock = q->queue_lock; 436 return lock && spin_is_locked(lock); 437 #else 438 return 1; 439 #endif 440 } 441 442 static inline void queue_flag_set_unlocked(unsigned int flag, 443 struct request_queue *q) 444 { 445 __set_bit(flag, &q->queue_flags); 446 } 447 448 static inline int queue_flag_test_and_clear(unsigned int flag, 449 struct request_queue *q) 450 { 451 WARN_ON_ONCE(!queue_is_locked(q)); 452 453 if (test_bit(flag, &q->queue_flags)) { 454 __clear_bit(flag, &q->queue_flags); 455 return 1; 456 } 457 458 return 0; 459 } 460 461 static inline int queue_flag_test_and_set(unsigned int flag, 462 struct request_queue *q) 463 { 464 WARN_ON_ONCE(!queue_is_locked(q)); 465 466 if (!test_bit(flag, &q->queue_flags)) { 467 __set_bit(flag, &q->queue_flags); 468 return 0; 469 } 470 471 return 1; 472 } 473 474 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 475 { 476 WARN_ON_ONCE(!queue_is_locked(q)); 477 __set_bit(flag, &q->queue_flags); 478 } 479 480 static inline void queue_flag_clear_unlocked(unsigned int flag, 481 struct request_queue *q) 482 { 483 __clear_bit(flag, &q->queue_flags); 484 } 485 486 static inline int queue_in_flight(struct request_queue *q) 487 { 488 return q->in_flight[0] + q->in_flight[1]; 489 } 490 491 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 492 { 493 WARN_ON_ONCE(!queue_is_locked(q)); 494 __clear_bit(flag, &q->queue_flags); 495 } 496 497 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 498 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 499 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 500 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 501 #define blk_queue_noxmerges(q) \ 502 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 503 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 504 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 505 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 506 #define blk_queue_stackable(q) \ 507 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 508 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 509 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \ 510 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags)) 511 512 #define blk_noretry_request(rq) \ 513 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 514 REQ_FAILFAST_DRIVER)) 515 516 #define blk_account_rq(rq) \ 517 (((rq)->cmd_flags & REQ_STARTED) && \ 518 ((rq)->cmd_type == REQ_TYPE_FS || \ 519 ((rq)->cmd_flags & REQ_DISCARD))) 520 521 #define blk_pm_request(rq) \ 522 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \ 523 (rq)->cmd_type == REQ_TYPE_PM_RESUME) 524 525 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 526 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 527 /* rq->queuelist of dequeued request must be list_empty() */ 528 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 529 530 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 531 532 #define rq_data_dir(rq) ((rq)->cmd_flags & 1) 533 534 static inline unsigned int blk_queue_cluster(struct request_queue *q) 535 { 536 return q->limits.cluster; 537 } 538 539 /* 540 * We regard a request as sync, if either a read or a sync write 541 */ 542 static inline bool rw_is_sync(unsigned int rw_flags) 543 { 544 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC); 545 } 546 547 static inline bool rq_is_sync(struct request *rq) 548 { 549 return rw_is_sync(rq->cmd_flags); 550 } 551 552 static inline int blk_queue_full(struct request_queue *q, int sync) 553 { 554 if (sync) 555 return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags); 556 return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags); 557 } 558 559 static inline void blk_set_queue_full(struct request_queue *q, int sync) 560 { 561 if (sync) 562 queue_flag_set(QUEUE_FLAG_SYNCFULL, q); 563 else 564 queue_flag_set(QUEUE_FLAG_ASYNCFULL, q); 565 } 566 567 static inline void blk_clear_queue_full(struct request_queue *q, int sync) 568 { 569 if (sync) 570 queue_flag_clear(QUEUE_FLAG_SYNCFULL, q); 571 else 572 queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q); 573 } 574 575 576 /* 577 * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may 578 * it already be started by driver. 579 */ 580 #define RQ_NOMERGE_FLAGS \ 581 (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA) 582 #define rq_mergeable(rq) \ 583 (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \ 584 (((rq)->cmd_flags & REQ_DISCARD) || \ 585 (rq)->cmd_type == REQ_TYPE_FS)) 586 587 /* 588 * q->prep_rq_fn return values 589 */ 590 #define BLKPREP_OK 0 /* serve it */ 591 #define BLKPREP_KILL 1 /* fatal error, kill */ 592 #define BLKPREP_DEFER 2 /* leave on queue */ 593 594 extern unsigned long blk_max_low_pfn, blk_max_pfn; 595 596 /* 597 * standard bounce addresses: 598 * 599 * BLK_BOUNCE_HIGH : bounce all highmem pages 600 * BLK_BOUNCE_ANY : don't bounce anything 601 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 602 */ 603 604 #if BITS_PER_LONG == 32 605 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 606 #else 607 #define BLK_BOUNCE_HIGH -1ULL 608 #endif 609 #define BLK_BOUNCE_ANY (-1ULL) 610 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 611 612 /* 613 * default timeout for SG_IO if none specified 614 */ 615 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 616 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 617 618 #ifdef CONFIG_BOUNCE 619 extern int init_emergency_isa_pool(void); 620 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 621 #else 622 static inline int init_emergency_isa_pool(void) 623 { 624 return 0; 625 } 626 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 627 { 628 } 629 #endif /* CONFIG_MMU */ 630 631 struct rq_map_data { 632 struct page **pages; 633 int page_order; 634 int nr_entries; 635 unsigned long offset; 636 int null_mapped; 637 int from_user; 638 }; 639 640 struct req_iterator { 641 int i; 642 struct bio *bio; 643 }; 644 645 /* This should not be used directly - use rq_for_each_segment */ 646 #define for_each_bio(_bio) \ 647 for (; _bio; _bio = _bio->bi_next) 648 #define __rq_for_each_bio(_bio, rq) \ 649 if ((rq->bio)) \ 650 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 651 652 #define rq_for_each_segment(bvl, _rq, _iter) \ 653 __rq_for_each_bio(_iter.bio, _rq) \ 654 bio_for_each_segment(bvl, _iter.bio, _iter.i) 655 656 #define rq_iter_last(rq, _iter) \ 657 (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1) 658 659 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 660 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 661 #endif 662 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 663 extern void rq_flush_dcache_pages(struct request *rq); 664 #else 665 static inline void rq_flush_dcache_pages(struct request *rq) 666 { 667 } 668 #endif 669 670 extern int blk_register_queue(struct gendisk *disk); 671 extern void blk_unregister_queue(struct gendisk *disk); 672 extern void generic_make_request(struct bio *bio); 673 extern void blk_rq_init(struct request_queue *q, struct request *rq); 674 extern void blk_put_request(struct request *); 675 extern void __blk_put_request(struct request_queue *, struct request *); 676 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 677 extern struct request *blk_make_request(struct request_queue *, struct bio *, 678 gfp_t); 679 extern void blk_requeue_request(struct request_queue *, struct request *); 680 extern void blk_add_request_payload(struct request *rq, struct page *page, 681 unsigned int len); 682 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); 683 extern int blk_lld_busy(struct request_queue *q); 684 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 685 struct bio_set *bs, gfp_t gfp_mask, 686 int (*bio_ctr)(struct bio *, struct bio *, void *), 687 void *data); 688 extern void blk_rq_unprep_clone(struct request *rq); 689 extern int blk_insert_cloned_request(struct request_queue *q, 690 struct request *rq); 691 extern void blk_delay_queue(struct request_queue *, unsigned long); 692 extern void blk_recount_segments(struct request_queue *, struct bio *); 693 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 694 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 695 unsigned int, void __user *); 696 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 697 unsigned int, void __user *); 698 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 699 struct scsi_ioctl_command __user *); 700 701 extern void blk_queue_bio(struct request_queue *q, struct bio *bio); 702 703 /* 704 * A queue has just exitted congestion. Note this in the global counter of 705 * congested queues, and wake up anyone who was waiting for requests to be 706 * put back. 707 */ 708 static inline void blk_clear_queue_congested(struct request_queue *q, int sync) 709 { 710 clear_bdi_congested(&q->backing_dev_info, sync); 711 } 712 713 /* 714 * A queue has just entered congestion. Flag that in the queue's VM-visible 715 * state flags and increment the global gounter of congested queues. 716 */ 717 static inline void blk_set_queue_congested(struct request_queue *q, int sync) 718 { 719 set_bdi_congested(&q->backing_dev_info, sync); 720 } 721 722 extern void blk_start_queue(struct request_queue *q); 723 extern void blk_stop_queue(struct request_queue *q); 724 extern void blk_sync_queue(struct request_queue *q); 725 extern void __blk_stop_queue(struct request_queue *q); 726 extern void __blk_run_queue(struct request_queue *q); 727 extern void blk_run_queue(struct request_queue *); 728 extern void blk_run_queue_async(struct request_queue *q); 729 extern int blk_rq_map_user(struct request_queue *, struct request *, 730 struct rq_map_data *, void __user *, unsigned long, 731 gfp_t); 732 extern int blk_rq_unmap_user(struct bio *); 733 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 734 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 735 struct rq_map_data *, struct sg_iovec *, int, 736 unsigned int, gfp_t); 737 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 738 struct request *, int); 739 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 740 struct request *, int, rq_end_io_fn *); 741 742 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 743 { 744 return bdev->bd_disk->queue; 745 } 746 747 /* 748 * blk_rq_pos() : the current sector 749 * blk_rq_bytes() : bytes left in the entire request 750 * blk_rq_cur_bytes() : bytes left in the current segment 751 * blk_rq_err_bytes() : bytes left till the next error boundary 752 * blk_rq_sectors() : sectors left in the entire request 753 * blk_rq_cur_sectors() : sectors left in the current segment 754 */ 755 static inline sector_t blk_rq_pos(const struct request *rq) 756 { 757 return rq->__sector; 758 } 759 760 static inline unsigned int blk_rq_bytes(const struct request *rq) 761 { 762 return rq->__data_len; 763 } 764 765 static inline int blk_rq_cur_bytes(const struct request *rq) 766 { 767 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 768 } 769 770 extern unsigned int blk_rq_err_bytes(const struct request *rq); 771 772 static inline unsigned int blk_rq_sectors(const struct request *rq) 773 { 774 return blk_rq_bytes(rq) >> 9; 775 } 776 777 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 778 { 779 return blk_rq_cur_bytes(rq) >> 9; 780 } 781 782 /* 783 * Request issue related functions. 784 */ 785 extern struct request *blk_peek_request(struct request_queue *q); 786 extern void blk_start_request(struct request *rq); 787 extern struct request *blk_fetch_request(struct request_queue *q); 788 789 /* 790 * Request completion related functions. 791 * 792 * blk_update_request() completes given number of bytes and updates 793 * the request without completing it. 794 * 795 * blk_end_request() and friends. __blk_end_request() must be called 796 * with the request queue spinlock acquired. 797 * 798 * Several drivers define their own end_request and call 799 * blk_end_request() for parts of the original function. 800 * This prevents code duplication in drivers. 801 */ 802 extern bool blk_update_request(struct request *rq, int error, 803 unsigned int nr_bytes); 804 extern bool blk_end_request(struct request *rq, int error, 805 unsigned int nr_bytes); 806 extern void blk_end_request_all(struct request *rq, int error); 807 extern bool blk_end_request_cur(struct request *rq, int error); 808 extern bool blk_end_request_err(struct request *rq, int error); 809 extern bool __blk_end_request(struct request *rq, int error, 810 unsigned int nr_bytes); 811 extern void __blk_end_request_all(struct request *rq, int error); 812 extern bool __blk_end_request_cur(struct request *rq, int error); 813 extern bool __blk_end_request_err(struct request *rq, int error); 814 815 extern void blk_complete_request(struct request *); 816 extern void __blk_complete_request(struct request *); 817 extern void blk_abort_request(struct request *); 818 extern void blk_abort_queue(struct request_queue *); 819 extern void blk_unprep_request(struct request *); 820 821 /* 822 * Access functions for manipulating queue properties 823 */ 824 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 825 spinlock_t *lock, int node_id); 826 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 827 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 828 request_fn_proc *, spinlock_t *); 829 extern void blk_cleanup_queue(struct request_queue *); 830 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 831 extern void blk_queue_bounce_limit(struct request_queue *, u64); 832 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int); 833 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 834 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 835 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 836 extern void blk_queue_max_discard_sectors(struct request_queue *q, 837 unsigned int max_discard_sectors); 838 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 839 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 840 extern void blk_queue_alignment_offset(struct request_queue *q, 841 unsigned int alignment); 842 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 843 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 844 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 845 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 846 extern void blk_set_default_limits(struct queue_limits *lim); 847 extern void blk_set_stacking_limits(struct queue_limits *lim); 848 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 849 sector_t offset); 850 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 851 sector_t offset); 852 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 853 sector_t offset); 854 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 855 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 856 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 857 extern int blk_queue_dma_drain(struct request_queue *q, 858 dma_drain_needed_fn *dma_drain_needed, 859 void *buf, unsigned int size); 860 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 861 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 862 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 863 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 864 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); 865 extern void blk_queue_dma_alignment(struct request_queue *, int); 866 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 867 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 868 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 869 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 870 extern void blk_queue_flush(struct request_queue *q, unsigned int flush); 871 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 872 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 873 874 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 875 extern void blk_dump_rq_flags(struct request *, char *); 876 extern long nr_blockdev_pages(void); 877 878 bool __must_check blk_get_queue(struct request_queue *); 879 struct request_queue *blk_alloc_queue(gfp_t); 880 struct request_queue *blk_alloc_queue_node(gfp_t, int); 881 extern void blk_put_queue(struct request_queue *); 882 883 /* 884 * blk_plug permits building a queue of related requests by holding the I/O 885 * fragments for a short period. This allows merging of sequential requests 886 * into single larger request. As the requests are moved from a per-task list to 887 * the device's request_queue in a batch, this results in improved scalability 888 * as the lock contention for request_queue lock is reduced. 889 * 890 * It is ok not to disable preemption when adding the request to the plug list 891 * or when attempting a merge, because blk_schedule_flush_list() will only flush 892 * the plug list when the task sleeps by itself. For details, please see 893 * schedule() where blk_schedule_flush_plug() is called. 894 */ 895 struct blk_plug { 896 unsigned long magic; /* detect uninitialized use-cases */ 897 struct list_head list; /* requests */ 898 struct list_head cb_list; /* md requires an unplug callback */ 899 unsigned int should_sort; /* list to be sorted before flushing? */ 900 }; 901 #define BLK_MAX_REQUEST_COUNT 16 902 903 struct blk_plug_cb { 904 struct list_head list; 905 void (*callback)(struct blk_plug_cb *); 906 }; 907 908 extern void blk_start_plug(struct blk_plug *); 909 extern void blk_finish_plug(struct blk_plug *); 910 extern void blk_flush_plug_list(struct blk_plug *, bool); 911 912 static inline void blk_flush_plug(struct task_struct *tsk) 913 { 914 struct blk_plug *plug = tsk->plug; 915 916 if (plug) 917 blk_flush_plug_list(plug, false); 918 } 919 920 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 921 { 922 struct blk_plug *plug = tsk->plug; 923 924 if (plug) 925 blk_flush_plug_list(plug, true); 926 } 927 928 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 929 { 930 struct blk_plug *plug = tsk->plug; 931 932 return plug && (!list_empty(&plug->list) || !list_empty(&plug->cb_list)); 933 } 934 935 /* 936 * tag stuff 937 */ 938 #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED) 939 extern int blk_queue_start_tag(struct request_queue *, struct request *); 940 extern struct request *blk_queue_find_tag(struct request_queue *, int); 941 extern void blk_queue_end_tag(struct request_queue *, struct request *); 942 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *); 943 extern void blk_queue_free_tags(struct request_queue *); 944 extern int blk_queue_resize_tags(struct request_queue *, int); 945 extern void blk_queue_invalidate_tags(struct request_queue *); 946 extern struct blk_queue_tag *blk_init_tags(int); 947 extern void blk_free_tags(struct blk_queue_tag *); 948 949 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 950 int tag) 951 { 952 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 953 return NULL; 954 return bqt->tag_index[tag]; 955 } 956 957 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */ 958 959 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 960 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 961 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 962 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 963 sector_t nr_sects, gfp_t gfp_mask); 964 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 965 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 966 { 967 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 968 nr_blocks << (sb->s_blocksize_bits - 9), 969 gfp_mask, flags); 970 } 971 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 972 sector_t nr_blocks, gfp_t gfp_mask) 973 { 974 return blkdev_issue_zeroout(sb->s_bdev, 975 block << (sb->s_blocksize_bits - 9), 976 nr_blocks << (sb->s_blocksize_bits - 9), 977 gfp_mask); 978 } 979 980 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 981 982 enum blk_default_limits { 983 BLK_MAX_SEGMENTS = 128, 984 BLK_SAFE_MAX_SECTORS = 255, 985 BLK_DEF_MAX_SECTORS = 1024, 986 BLK_MAX_SEGMENT_SIZE = 65536, 987 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 988 }; 989 990 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 991 992 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 993 { 994 return q->limits.bounce_pfn; 995 } 996 997 static inline unsigned long queue_segment_boundary(struct request_queue *q) 998 { 999 return q->limits.seg_boundary_mask; 1000 } 1001 1002 static inline unsigned int queue_max_sectors(struct request_queue *q) 1003 { 1004 return q->limits.max_sectors; 1005 } 1006 1007 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1008 { 1009 return q->limits.max_hw_sectors; 1010 } 1011 1012 static inline unsigned short queue_max_segments(struct request_queue *q) 1013 { 1014 return q->limits.max_segments; 1015 } 1016 1017 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1018 { 1019 return q->limits.max_segment_size; 1020 } 1021 1022 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1023 { 1024 int retval = 512; 1025 1026 if (q && q->limits.logical_block_size) 1027 retval = q->limits.logical_block_size; 1028 1029 return retval; 1030 } 1031 1032 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1033 { 1034 return queue_logical_block_size(bdev_get_queue(bdev)); 1035 } 1036 1037 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1038 { 1039 return q->limits.physical_block_size; 1040 } 1041 1042 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1043 { 1044 return queue_physical_block_size(bdev_get_queue(bdev)); 1045 } 1046 1047 static inline unsigned int queue_io_min(struct request_queue *q) 1048 { 1049 return q->limits.io_min; 1050 } 1051 1052 static inline int bdev_io_min(struct block_device *bdev) 1053 { 1054 return queue_io_min(bdev_get_queue(bdev)); 1055 } 1056 1057 static inline unsigned int queue_io_opt(struct request_queue *q) 1058 { 1059 return q->limits.io_opt; 1060 } 1061 1062 static inline int bdev_io_opt(struct block_device *bdev) 1063 { 1064 return queue_io_opt(bdev_get_queue(bdev)); 1065 } 1066 1067 static inline int queue_alignment_offset(struct request_queue *q) 1068 { 1069 if (q->limits.misaligned) 1070 return -1; 1071 1072 return q->limits.alignment_offset; 1073 } 1074 1075 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1076 { 1077 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1078 unsigned int alignment = (sector << 9) & (granularity - 1); 1079 1080 return (granularity + lim->alignment_offset - alignment) 1081 & (granularity - 1); 1082 } 1083 1084 static inline int bdev_alignment_offset(struct block_device *bdev) 1085 { 1086 struct request_queue *q = bdev_get_queue(bdev); 1087 1088 if (q->limits.misaligned) 1089 return -1; 1090 1091 if (bdev != bdev->bd_contains) 1092 return bdev->bd_part->alignment_offset; 1093 1094 return q->limits.alignment_offset; 1095 } 1096 1097 static inline int queue_discard_alignment(struct request_queue *q) 1098 { 1099 if (q->limits.discard_misaligned) 1100 return -1; 1101 1102 return q->limits.discard_alignment; 1103 } 1104 1105 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1106 { 1107 unsigned int alignment = (sector << 9) & (lim->discard_granularity - 1); 1108 1109 if (!lim->max_discard_sectors) 1110 return 0; 1111 1112 return (lim->discard_granularity + lim->discard_alignment - alignment) 1113 & (lim->discard_granularity - 1); 1114 } 1115 1116 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1117 { 1118 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) 1119 return 1; 1120 1121 return 0; 1122 } 1123 1124 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1125 { 1126 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1127 } 1128 1129 static inline int queue_dma_alignment(struct request_queue *q) 1130 { 1131 return q ? q->dma_alignment : 511; 1132 } 1133 1134 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1135 unsigned int len) 1136 { 1137 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1138 return !(addr & alignment) && !(len & alignment); 1139 } 1140 1141 /* assumes size > 256 */ 1142 static inline unsigned int blksize_bits(unsigned int size) 1143 { 1144 unsigned int bits = 8; 1145 do { 1146 bits++; 1147 size >>= 1; 1148 } while (size > 256); 1149 return bits; 1150 } 1151 1152 static inline unsigned int block_size(struct block_device *bdev) 1153 { 1154 return bdev->bd_block_size; 1155 } 1156 1157 static inline bool queue_flush_queueable(struct request_queue *q) 1158 { 1159 return !q->flush_not_queueable; 1160 } 1161 1162 typedef struct {struct page *v;} Sector; 1163 1164 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1165 1166 static inline void put_dev_sector(Sector p) 1167 { 1168 page_cache_release(p.v); 1169 } 1170 1171 struct work_struct; 1172 int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); 1173 1174 #ifdef CONFIG_BLK_CGROUP 1175 /* 1176 * This should not be using sched_clock(). A real patch is in progress 1177 * to fix this up, until that is in place we need to disable preemption 1178 * around sched_clock() in this function and set_io_start_time_ns(). 1179 */ 1180 static inline void set_start_time_ns(struct request *req) 1181 { 1182 preempt_disable(); 1183 req->start_time_ns = sched_clock(); 1184 preempt_enable(); 1185 } 1186 1187 static inline void set_io_start_time_ns(struct request *req) 1188 { 1189 preempt_disable(); 1190 req->io_start_time_ns = sched_clock(); 1191 preempt_enable(); 1192 } 1193 1194 static inline uint64_t rq_start_time_ns(struct request *req) 1195 { 1196 return req->start_time_ns; 1197 } 1198 1199 static inline uint64_t rq_io_start_time_ns(struct request *req) 1200 { 1201 return req->io_start_time_ns; 1202 } 1203 #else 1204 static inline void set_start_time_ns(struct request *req) {} 1205 static inline void set_io_start_time_ns(struct request *req) {} 1206 static inline uint64_t rq_start_time_ns(struct request *req) 1207 { 1208 return 0; 1209 } 1210 static inline uint64_t rq_io_start_time_ns(struct request *req) 1211 { 1212 return 0; 1213 } 1214 #endif 1215 1216 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1217 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1218 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1219 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1220 1221 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1222 1223 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */ 1224 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */ 1225 1226 struct blk_integrity_exchg { 1227 void *prot_buf; 1228 void *data_buf; 1229 sector_t sector; 1230 unsigned int data_size; 1231 unsigned short sector_size; 1232 const char *disk_name; 1233 }; 1234 1235 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *); 1236 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *); 1237 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int); 1238 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int); 1239 1240 struct blk_integrity { 1241 integrity_gen_fn *generate_fn; 1242 integrity_vrfy_fn *verify_fn; 1243 integrity_set_tag_fn *set_tag_fn; 1244 integrity_get_tag_fn *get_tag_fn; 1245 1246 unsigned short flags; 1247 unsigned short tuple_size; 1248 unsigned short sector_size; 1249 unsigned short tag_size; 1250 1251 const char *name; 1252 1253 struct kobject kobj; 1254 }; 1255 1256 extern bool blk_integrity_is_initialized(struct gendisk *); 1257 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); 1258 extern void blk_integrity_unregister(struct gendisk *); 1259 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1260 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1261 struct scatterlist *); 1262 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1263 extern int blk_integrity_merge_rq(struct request_queue *, struct request *, 1264 struct request *); 1265 extern int blk_integrity_merge_bio(struct request_queue *, struct request *, 1266 struct bio *); 1267 1268 static inline 1269 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1270 { 1271 return bdev->bd_disk->integrity; 1272 } 1273 1274 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1275 { 1276 return disk->integrity; 1277 } 1278 1279 static inline int blk_integrity_rq(struct request *rq) 1280 { 1281 if (rq->bio == NULL) 1282 return 0; 1283 1284 return bio_integrity(rq->bio); 1285 } 1286 1287 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1288 unsigned int segs) 1289 { 1290 q->limits.max_integrity_segments = segs; 1291 } 1292 1293 static inline unsigned short 1294 queue_max_integrity_segments(struct request_queue *q) 1295 { 1296 return q->limits.max_integrity_segments; 1297 } 1298 1299 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1300 1301 struct bio; 1302 struct block_device; 1303 struct gendisk; 1304 struct blk_integrity; 1305 1306 static inline int blk_integrity_rq(struct request *rq) 1307 { 1308 return 0; 1309 } 1310 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1311 struct bio *b) 1312 { 1313 return 0; 1314 } 1315 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1316 struct bio *b, 1317 struct scatterlist *s) 1318 { 1319 return 0; 1320 } 1321 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1322 { 1323 return 0; 1324 } 1325 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1326 { 1327 return NULL; 1328 } 1329 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1330 { 1331 return 0; 1332 } 1333 static inline int blk_integrity_register(struct gendisk *d, 1334 struct blk_integrity *b) 1335 { 1336 return 0; 1337 } 1338 static inline void blk_integrity_unregister(struct gendisk *d) 1339 { 1340 } 1341 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1342 unsigned int segs) 1343 { 1344 } 1345 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1346 { 1347 return 0; 1348 } 1349 static inline int blk_integrity_merge_rq(struct request_queue *rq, 1350 struct request *r1, 1351 struct request *r2) 1352 { 1353 return 0; 1354 } 1355 static inline int blk_integrity_merge_bio(struct request_queue *rq, 1356 struct request *r, 1357 struct bio *b) 1358 { 1359 return 0; 1360 } 1361 static inline bool blk_integrity_is_initialized(struct gendisk *g) 1362 { 1363 return 0; 1364 } 1365 1366 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1367 1368 struct block_device_operations { 1369 int (*open) (struct block_device *, fmode_t); 1370 int (*release) (struct gendisk *, fmode_t); 1371 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1372 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1373 int (*direct_access) (struct block_device *, sector_t, 1374 void **, unsigned long *); 1375 unsigned int (*check_events) (struct gendisk *disk, 1376 unsigned int clearing); 1377 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1378 int (*media_changed) (struct gendisk *); 1379 void (*unlock_native_capacity) (struct gendisk *); 1380 int (*revalidate_disk) (struct gendisk *); 1381 int (*getgeo)(struct block_device *, struct hd_geometry *); 1382 /* this callback is with swap_lock and sometimes page table lock held */ 1383 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1384 struct module *owner; 1385 }; 1386 1387 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1388 unsigned long); 1389 #else /* CONFIG_BLOCK */ 1390 /* 1391 * stubs for when the block layer is configured out 1392 */ 1393 #define buffer_heads_over_limit 0 1394 1395 static inline long nr_blockdev_pages(void) 1396 { 1397 return 0; 1398 } 1399 1400 struct blk_plug { 1401 }; 1402 1403 static inline void blk_start_plug(struct blk_plug *plug) 1404 { 1405 } 1406 1407 static inline void blk_finish_plug(struct blk_plug *plug) 1408 { 1409 } 1410 1411 static inline void blk_flush_plug(struct task_struct *task) 1412 { 1413 } 1414 1415 static inline void blk_schedule_flush_plug(struct task_struct *task) 1416 { 1417 } 1418 1419 1420 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1421 { 1422 return false; 1423 } 1424 1425 #endif /* CONFIG_BLOCK */ 1426 1427 #endif 1428