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/timer.h> 12 #include <linux/workqueue.h> 13 #include <linux/pagemap.h> 14 #include <linux/backing-dev.h> 15 #include <linux/wait.h> 16 #include <linux/mempool.h> 17 #include <linux/bio.h> 18 #include <linux/stringify.h> 19 #include <linux/gfp.h> 20 #include <linux/bsg.h> 21 #include <linux/smp.h> 22 23 #include <asm/scatterlist.h> 24 25 struct module; 26 struct scsi_ioctl_command; 27 28 struct request_queue; 29 struct elevator_queue; 30 struct request_pm_state; 31 struct blk_trace; 32 struct request; 33 struct sg_io_hdr; 34 struct bsg_job; 35 struct blkcg_gq; 36 37 #define BLKDEV_MIN_RQ 4 38 #define BLKDEV_MAX_RQ 128 /* Default maximum */ 39 40 /* 41 * Maximum number of blkcg policies allowed to be registered concurrently. 42 * Defined here to simplify include dependency. 43 */ 44 #define BLKCG_MAX_POLS 2 45 46 struct request; 47 typedef void (rq_end_io_fn)(struct request *, int); 48 49 struct request_list { 50 /* 51 * count[], starved[], and wait[] are indexed by 52 * BLK_RW_SYNC/BLK_RW_ASYNC 53 */ 54 int count[2]; 55 int starved[2]; 56 int elvpriv; 57 mempool_t *rq_pool; 58 wait_queue_head_t wait[2]; 59 }; 60 61 /* 62 * request command types 63 */ 64 enum rq_cmd_type_bits { 65 REQ_TYPE_FS = 1, /* fs request */ 66 REQ_TYPE_BLOCK_PC, /* scsi command */ 67 REQ_TYPE_SENSE, /* sense request */ 68 REQ_TYPE_PM_SUSPEND, /* suspend request */ 69 REQ_TYPE_PM_RESUME, /* resume request */ 70 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */ 71 REQ_TYPE_SPECIAL, /* driver defined type */ 72 /* 73 * for ATA/ATAPI devices. this really doesn't belong here, ide should 74 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver 75 * private REQ_LB opcodes to differentiate what type of request this is 76 */ 77 REQ_TYPE_ATA_TASKFILE, 78 REQ_TYPE_ATA_PC, 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 * if you modify this structure, be sure to check block/blk-core.c:blk_rq_init() 86 * as well! 87 */ 88 struct request { 89 struct list_head queuelist; 90 struct call_single_data csd; 91 92 struct request_queue *q; 93 94 unsigned int cmd_flags; 95 enum rq_cmd_type_bits cmd_type; 96 unsigned long atomic_flags; 97 98 int cpu; 99 100 /* the following two fields are internal, NEVER access directly */ 101 unsigned int __data_len; /* total data len */ 102 sector_t __sector; /* sector cursor */ 103 104 struct bio *bio; 105 struct bio *biotail; 106 107 struct hlist_node hash; /* merge hash */ 108 /* 109 * The rb_node is only used inside the io scheduler, requests 110 * are pruned when moved to the dispatch queue. So let the 111 * completion_data share space with the rb_node. 112 */ 113 union { 114 struct rb_node rb_node; /* sort/lookup */ 115 void *completion_data; 116 }; 117 118 /* 119 * Three pointers are available for the IO schedulers, if they need 120 * more they have to dynamically allocate it. Flush requests are 121 * never put on the IO scheduler. So let the flush fields share 122 * space with the elevator data. 123 */ 124 union { 125 struct { 126 struct io_cq *icq; 127 void *priv[2]; 128 } elv; 129 130 struct { 131 unsigned int seq; 132 struct list_head list; 133 rq_end_io_fn *saved_end_io; 134 } flush; 135 }; 136 137 struct gendisk *rq_disk; 138 struct hd_struct *part; 139 unsigned long start_time; 140 #ifdef CONFIG_BLK_CGROUP 141 unsigned long long start_time_ns; 142 unsigned long long io_start_time_ns; /* when passed to hardware */ 143 #endif 144 /* Number of scatter-gather DMA addr+len pairs after 145 * physical address coalescing is performed. 146 */ 147 unsigned short nr_phys_segments; 148 #if defined(CONFIG_BLK_DEV_INTEGRITY) 149 unsigned short nr_integrity_segments; 150 #endif 151 152 unsigned short ioprio; 153 154 int ref_count; 155 156 void *special; /* opaque pointer available for LLD use */ 157 char *buffer; /* kaddr of the current segment if available */ 158 159 int tag; 160 int errors; 161 162 /* 163 * when request is used as a packet command carrier 164 */ 165 unsigned char __cmd[BLK_MAX_CDB]; 166 unsigned char *cmd; 167 unsigned short cmd_len; 168 169 unsigned int extra_len; /* length of alignment and padding */ 170 unsigned int sense_len; 171 unsigned int resid_len; /* residual count */ 172 void *sense; 173 174 unsigned long deadline; 175 struct list_head timeout_list; 176 unsigned int timeout; 177 int retries; 178 179 /* 180 * completion callback. 181 */ 182 rq_end_io_fn *end_io; 183 void *end_io_data; 184 185 /* for bidi */ 186 struct request *next_rq; 187 }; 188 189 static inline unsigned short req_get_ioprio(struct request *req) 190 { 191 return req->ioprio; 192 } 193 194 /* 195 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME 196 * requests. Some step values could eventually be made generic. 197 */ 198 struct request_pm_state 199 { 200 /* PM state machine step value, currently driver specific */ 201 int pm_step; 202 /* requested PM state value (S1, S2, S3, S4, ...) */ 203 u32 pm_state; 204 void* data; /* for driver use */ 205 }; 206 207 #include <linux/elevator.h> 208 209 typedef void (request_fn_proc) (struct request_queue *q); 210 typedef void (make_request_fn) (struct request_queue *q, struct bio *bio); 211 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 212 typedef void (unprep_rq_fn) (struct request_queue *, struct request *); 213 214 struct bio_vec; 215 struct bvec_merge_data { 216 struct block_device *bi_bdev; 217 sector_t bi_sector; 218 unsigned bi_size; 219 unsigned long bi_rw; 220 }; 221 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *, 222 struct bio_vec *); 223 typedef void (softirq_done_fn)(struct request *); 224 typedef int (dma_drain_needed_fn)(struct request *); 225 typedef int (lld_busy_fn) (struct request_queue *q); 226 typedef int (bsg_job_fn) (struct bsg_job *); 227 228 enum blk_eh_timer_return { 229 BLK_EH_NOT_HANDLED, 230 BLK_EH_HANDLED, 231 BLK_EH_RESET_TIMER, 232 }; 233 234 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 235 236 enum blk_queue_state { 237 Queue_down, 238 Queue_up, 239 }; 240 241 struct blk_queue_tag { 242 struct request **tag_index; /* map of busy tags */ 243 unsigned long *tag_map; /* bit map of free/busy tags */ 244 int busy; /* current depth */ 245 int max_depth; /* what we will send to device */ 246 int real_max_depth; /* what the array can hold */ 247 atomic_t refcnt; /* map can be shared */ 248 }; 249 250 #define BLK_SCSI_MAX_CMDS (256) 251 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 252 253 struct queue_limits { 254 unsigned long bounce_pfn; 255 unsigned long seg_boundary_mask; 256 257 unsigned int max_hw_sectors; 258 unsigned int max_sectors; 259 unsigned int max_segment_size; 260 unsigned int physical_block_size; 261 unsigned int alignment_offset; 262 unsigned int io_min; 263 unsigned int io_opt; 264 unsigned int max_discard_sectors; 265 unsigned int discard_granularity; 266 unsigned int discard_alignment; 267 268 unsigned short logical_block_size; 269 unsigned short max_segments; 270 unsigned short max_integrity_segments; 271 272 unsigned char misaligned; 273 unsigned char discard_misaligned; 274 unsigned char cluster; 275 unsigned char discard_zeroes_data; 276 }; 277 278 struct request_queue { 279 /* 280 * Together with queue_head for cacheline sharing 281 */ 282 struct list_head queue_head; 283 struct request *last_merge; 284 struct elevator_queue *elevator; 285 286 /* 287 * the queue request freelist, one for reads and one for writes 288 */ 289 struct request_list rq; 290 291 request_fn_proc *request_fn; 292 make_request_fn *make_request_fn; 293 prep_rq_fn *prep_rq_fn; 294 unprep_rq_fn *unprep_rq_fn; 295 merge_bvec_fn *merge_bvec_fn; 296 softirq_done_fn *softirq_done_fn; 297 rq_timed_out_fn *rq_timed_out_fn; 298 dma_drain_needed_fn *dma_drain_needed; 299 lld_busy_fn *lld_busy_fn; 300 301 /* 302 * Dispatch queue sorting 303 */ 304 sector_t end_sector; 305 struct request *boundary_rq; 306 307 /* 308 * Delayed queue handling 309 */ 310 struct delayed_work delay_work; 311 312 struct backing_dev_info backing_dev_info; 313 314 /* 315 * The queue owner gets to use this for whatever they like. 316 * ll_rw_blk doesn't touch it. 317 */ 318 void *queuedata; 319 320 /* 321 * various queue flags, see QUEUE_* below 322 */ 323 unsigned long queue_flags; 324 325 /* 326 * ida allocated id for this queue. Used to index queues from 327 * ioctx. 328 */ 329 int id; 330 331 /* 332 * queue needs bounce pages for pages above this limit 333 */ 334 gfp_t bounce_gfp; 335 336 /* 337 * protects queue structures from reentrancy. ->__queue_lock should 338 * _never_ be used directly, it is queue private. always use 339 * ->queue_lock. 340 */ 341 spinlock_t __queue_lock; 342 spinlock_t *queue_lock; 343 344 /* 345 * queue kobject 346 */ 347 struct kobject kobj; 348 349 /* 350 * queue settings 351 */ 352 unsigned long nr_requests; /* Max # of requests */ 353 unsigned int nr_congestion_on; 354 unsigned int nr_congestion_off; 355 unsigned int nr_batching; 356 357 unsigned int dma_drain_size; 358 void *dma_drain_buffer; 359 unsigned int dma_pad_mask; 360 unsigned int dma_alignment; 361 362 struct blk_queue_tag *queue_tags; 363 struct list_head tag_busy_list; 364 365 unsigned int nr_sorted; 366 unsigned int in_flight[2]; 367 368 unsigned int rq_timeout; 369 struct timer_list timeout; 370 struct list_head timeout_list; 371 372 struct list_head icq_list; 373 #ifdef CONFIG_BLK_CGROUP 374 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); 375 struct blkcg_gq *root_blkg; 376 struct list_head blkg_list; 377 #endif 378 379 struct queue_limits limits; 380 381 /* 382 * sg stuff 383 */ 384 unsigned int sg_timeout; 385 unsigned int sg_reserved_size; 386 int node; 387 #ifdef CONFIG_BLK_DEV_IO_TRACE 388 struct blk_trace *blk_trace; 389 #endif 390 /* 391 * for flush operations 392 */ 393 unsigned int flush_flags; 394 unsigned int flush_not_queueable:1; 395 unsigned int flush_queue_delayed:1; 396 unsigned int flush_pending_idx:1; 397 unsigned int flush_running_idx:1; 398 unsigned long flush_pending_since; 399 struct list_head flush_queue[2]; 400 struct list_head flush_data_in_flight; 401 struct request flush_rq; 402 403 struct mutex sysfs_lock; 404 405 int bypass_depth; 406 407 #if defined(CONFIG_BLK_DEV_BSG) 408 bsg_job_fn *bsg_job_fn; 409 int bsg_job_size; 410 struct bsg_class_device bsg_dev; 411 #endif 412 413 #ifdef CONFIG_BLK_CGROUP 414 struct list_head all_q_node; 415 #endif 416 #ifdef CONFIG_BLK_DEV_THROTTLING 417 /* Throttle data */ 418 struct throtl_data *td; 419 #endif 420 }; 421 422 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 423 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 424 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 425 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 426 #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ 427 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */ 428 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ 429 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ 430 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ 431 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ 432 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ 433 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ 434 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 435 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ 436 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ 437 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ 438 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ 439 #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */ 440 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ 441 442 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 443 (1 << QUEUE_FLAG_STACKABLE) | \ 444 (1 << QUEUE_FLAG_SAME_COMP) | \ 445 (1 << QUEUE_FLAG_ADD_RANDOM)) 446 447 static inline void queue_lockdep_assert_held(struct request_queue *q) 448 { 449 if (q->queue_lock) 450 lockdep_assert_held(q->queue_lock); 451 } 452 453 static inline void queue_flag_set_unlocked(unsigned int flag, 454 struct request_queue *q) 455 { 456 __set_bit(flag, &q->queue_flags); 457 } 458 459 static inline int queue_flag_test_and_clear(unsigned int flag, 460 struct request_queue *q) 461 { 462 queue_lockdep_assert_held(q); 463 464 if (test_bit(flag, &q->queue_flags)) { 465 __clear_bit(flag, &q->queue_flags); 466 return 1; 467 } 468 469 return 0; 470 } 471 472 static inline int queue_flag_test_and_set(unsigned int flag, 473 struct request_queue *q) 474 { 475 queue_lockdep_assert_held(q); 476 477 if (!test_bit(flag, &q->queue_flags)) { 478 __set_bit(flag, &q->queue_flags); 479 return 0; 480 } 481 482 return 1; 483 } 484 485 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 486 { 487 queue_lockdep_assert_held(q); 488 __set_bit(flag, &q->queue_flags); 489 } 490 491 static inline void queue_flag_clear_unlocked(unsigned int flag, 492 struct request_queue *q) 493 { 494 __clear_bit(flag, &q->queue_flags); 495 } 496 497 static inline int queue_in_flight(struct request_queue *q) 498 { 499 return q->in_flight[0] + q->in_flight[1]; 500 } 501 502 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 503 { 504 queue_lockdep_assert_held(q); 505 __clear_bit(flag, &q->queue_flags); 506 } 507 508 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 509 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 510 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 511 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags) 512 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 513 #define blk_queue_noxmerges(q) \ 514 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 515 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 516 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 517 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 518 #define blk_queue_stackable(q) \ 519 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 520 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 521 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \ 522 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags)) 523 524 #define blk_noretry_request(rq) \ 525 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 526 REQ_FAILFAST_DRIVER)) 527 528 #define blk_account_rq(rq) \ 529 (((rq)->cmd_flags & REQ_STARTED) && \ 530 ((rq)->cmd_type == REQ_TYPE_FS || \ 531 ((rq)->cmd_flags & REQ_DISCARD))) 532 533 #define blk_pm_request(rq) \ 534 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \ 535 (rq)->cmd_type == REQ_TYPE_PM_RESUME) 536 537 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 538 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 539 /* rq->queuelist of dequeued request must be list_empty() */ 540 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 541 542 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 543 544 #define rq_data_dir(rq) ((rq)->cmd_flags & 1) 545 546 static inline unsigned int blk_queue_cluster(struct request_queue *q) 547 { 548 return q->limits.cluster; 549 } 550 551 /* 552 * We regard a request as sync, if either a read or a sync write 553 */ 554 static inline bool rw_is_sync(unsigned int rw_flags) 555 { 556 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC); 557 } 558 559 static inline bool rq_is_sync(struct request *rq) 560 { 561 return rw_is_sync(rq->cmd_flags); 562 } 563 564 static inline int blk_queue_full(struct request_queue *q, int sync) 565 { 566 if (sync) 567 return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags); 568 return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags); 569 } 570 571 static inline void blk_set_queue_full(struct request_queue *q, int sync) 572 { 573 if (sync) 574 queue_flag_set(QUEUE_FLAG_SYNCFULL, q); 575 else 576 queue_flag_set(QUEUE_FLAG_ASYNCFULL, q); 577 } 578 579 static inline void blk_clear_queue_full(struct request_queue *q, int sync) 580 { 581 if (sync) 582 queue_flag_clear(QUEUE_FLAG_SYNCFULL, q); 583 else 584 queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q); 585 } 586 587 588 /* 589 * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may 590 * it already be started by driver. 591 */ 592 #define RQ_NOMERGE_FLAGS \ 593 (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA) 594 #define rq_mergeable(rq) \ 595 (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \ 596 (((rq)->cmd_flags & REQ_DISCARD) || \ 597 (rq)->cmd_type == REQ_TYPE_FS)) 598 599 /* 600 * q->prep_rq_fn return values 601 */ 602 #define BLKPREP_OK 0 /* serve it */ 603 #define BLKPREP_KILL 1 /* fatal error, kill */ 604 #define BLKPREP_DEFER 2 /* leave on queue */ 605 606 extern unsigned long blk_max_low_pfn, blk_max_pfn; 607 608 /* 609 * standard bounce addresses: 610 * 611 * BLK_BOUNCE_HIGH : bounce all highmem pages 612 * BLK_BOUNCE_ANY : don't bounce anything 613 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 614 */ 615 616 #if BITS_PER_LONG == 32 617 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 618 #else 619 #define BLK_BOUNCE_HIGH -1ULL 620 #endif 621 #define BLK_BOUNCE_ANY (-1ULL) 622 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 623 624 /* 625 * default timeout for SG_IO if none specified 626 */ 627 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 628 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 629 630 #ifdef CONFIG_BOUNCE 631 extern int init_emergency_isa_pool(void); 632 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 633 #else 634 static inline int init_emergency_isa_pool(void) 635 { 636 return 0; 637 } 638 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 639 { 640 } 641 #endif /* CONFIG_MMU */ 642 643 struct rq_map_data { 644 struct page **pages; 645 int page_order; 646 int nr_entries; 647 unsigned long offset; 648 int null_mapped; 649 int from_user; 650 }; 651 652 struct req_iterator { 653 int i; 654 struct bio *bio; 655 }; 656 657 /* This should not be used directly - use rq_for_each_segment */ 658 #define for_each_bio(_bio) \ 659 for (; _bio; _bio = _bio->bi_next) 660 #define __rq_for_each_bio(_bio, rq) \ 661 if ((rq->bio)) \ 662 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 663 664 #define rq_for_each_segment(bvl, _rq, _iter) \ 665 __rq_for_each_bio(_iter.bio, _rq) \ 666 bio_for_each_segment(bvl, _iter.bio, _iter.i) 667 668 #define rq_iter_last(rq, _iter) \ 669 (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1) 670 671 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 672 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 673 #endif 674 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 675 extern void rq_flush_dcache_pages(struct request *rq); 676 #else 677 static inline void rq_flush_dcache_pages(struct request *rq) 678 { 679 } 680 #endif 681 682 extern int blk_register_queue(struct gendisk *disk); 683 extern void blk_unregister_queue(struct gendisk *disk); 684 extern void generic_make_request(struct bio *bio); 685 extern void blk_rq_init(struct request_queue *q, struct request *rq); 686 extern void blk_put_request(struct request *); 687 extern void __blk_put_request(struct request_queue *, struct request *); 688 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 689 extern struct request *blk_make_request(struct request_queue *, struct bio *, 690 gfp_t); 691 extern void blk_requeue_request(struct request_queue *, struct request *); 692 extern void blk_add_request_payload(struct request *rq, struct page *page, 693 unsigned int len); 694 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); 695 extern int blk_lld_busy(struct request_queue *q); 696 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 697 struct bio_set *bs, gfp_t gfp_mask, 698 int (*bio_ctr)(struct bio *, struct bio *, void *), 699 void *data); 700 extern void blk_rq_unprep_clone(struct request *rq); 701 extern int blk_insert_cloned_request(struct request_queue *q, 702 struct request *rq); 703 extern void blk_delay_queue(struct request_queue *, unsigned long); 704 extern void blk_recount_segments(struct request_queue *, struct bio *); 705 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 706 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 707 unsigned int, void __user *); 708 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 709 unsigned int, void __user *); 710 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 711 struct scsi_ioctl_command __user *); 712 713 extern void blk_queue_bio(struct request_queue *q, struct bio *bio); 714 715 /* 716 * A queue has just exitted congestion. Note this in the global counter of 717 * congested queues, and wake up anyone who was waiting for requests to be 718 * put back. 719 */ 720 static inline void blk_clear_queue_congested(struct request_queue *q, int sync) 721 { 722 clear_bdi_congested(&q->backing_dev_info, sync); 723 } 724 725 /* 726 * A queue has just entered congestion. Flag that in the queue's VM-visible 727 * state flags and increment the global gounter of congested queues. 728 */ 729 static inline void blk_set_queue_congested(struct request_queue *q, int sync) 730 { 731 set_bdi_congested(&q->backing_dev_info, sync); 732 } 733 734 extern void blk_start_queue(struct request_queue *q); 735 extern void blk_stop_queue(struct request_queue *q); 736 extern void blk_sync_queue(struct request_queue *q); 737 extern void __blk_stop_queue(struct request_queue *q); 738 extern void __blk_run_queue(struct request_queue *q); 739 extern void blk_run_queue(struct request_queue *); 740 extern void blk_run_queue_async(struct request_queue *q); 741 extern int blk_rq_map_user(struct request_queue *, struct request *, 742 struct rq_map_data *, void __user *, unsigned long, 743 gfp_t); 744 extern int blk_rq_unmap_user(struct bio *); 745 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 746 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 747 struct rq_map_data *, struct sg_iovec *, int, 748 unsigned int, gfp_t); 749 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 750 struct request *, int); 751 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 752 struct request *, int, rq_end_io_fn *); 753 754 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 755 { 756 return bdev->bd_disk->queue; 757 } 758 759 /* 760 * blk_rq_pos() : the current sector 761 * blk_rq_bytes() : bytes left in the entire request 762 * blk_rq_cur_bytes() : bytes left in the current segment 763 * blk_rq_err_bytes() : bytes left till the next error boundary 764 * blk_rq_sectors() : sectors left in the entire request 765 * blk_rq_cur_sectors() : sectors left in the current segment 766 */ 767 static inline sector_t blk_rq_pos(const struct request *rq) 768 { 769 return rq->__sector; 770 } 771 772 static inline unsigned int blk_rq_bytes(const struct request *rq) 773 { 774 return rq->__data_len; 775 } 776 777 static inline int blk_rq_cur_bytes(const struct request *rq) 778 { 779 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 780 } 781 782 extern unsigned int blk_rq_err_bytes(const struct request *rq); 783 784 static inline unsigned int blk_rq_sectors(const struct request *rq) 785 { 786 return blk_rq_bytes(rq) >> 9; 787 } 788 789 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 790 { 791 return blk_rq_cur_bytes(rq) >> 9; 792 } 793 794 /* 795 * Request issue related functions. 796 */ 797 extern struct request *blk_peek_request(struct request_queue *q); 798 extern void blk_start_request(struct request *rq); 799 extern struct request *blk_fetch_request(struct request_queue *q); 800 801 /* 802 * Request completion related functions. 803 * 804 * blk_update_request() completes given number of bytes and updates 805 * the request without completing it. 806 * 807 * blk_end_request() and friends. __blk_end_request() must be called 808 * with the request queue spinlock acquired. 809 * 810 * Several drivers define their own end_request and call 811 * blk_end_request() for parts of the original function. 812 * This prevents code duplication in drivers. 813 */ 814 extern bool blk_update_request(struct request *rq, int error, 815 unsigned int nr_bytes); 816 extern bool blk_end_request(struct request *rq, int error, 817 unsigned int nr_bytes); 818 extern void blk_end_request_all(struct request *rq, int error); 819 extern bool blk_end_request_cur(struct request *rq, int error); 820 extern bool blk_end_request_err(struct request *rq, int error); 821 extern bool __blk_end_request(struct request *rq, int error, 822 unsigned int nr_bytes); 823 extern void __blk_end_request_all(struct request *rq, int error); 824 extern bool __blk_end_request_cur(struct request *rq, int error); 825 extern bool __blk_end_request_err(struct request *rq, int error); 826 827 extern void blk_complete_request(struct request *); 828 extern void __blk_complete_request(struct request *); 829 extern void blk_abort_request(struct request *); 830 extern void blk_unprep_request(struct request *); 831 832 /* 833 * Access functions for manipulating queue properties 834 */ 835 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 836 spinlock_t *lock, int node_id); 837 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 838 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 839 request_fn_proc *, spinlock_t *); 840 extern void blk_cleanup_queue(struct request_queue *); 841 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 842 extern void blk_queue_bounce_limit(struct request_queue *, u64); 843 extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int); 844 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 845 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 846 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 847 extern void blk_queue_max_discard_sectors(struct request_queue *q, 848 unsigned int max_discard_sectors); 849 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 850 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 851 extern void blk_queue_alignment_offset(struct request_queue *q, 852 unsigned int alignment); 853 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 854 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 855 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 856 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 857 extern void blk_set_default_limits(struct queue_limits *lim); 858 extern void blk_set_stacking_limits(struct queue_limits *lim); 859 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 860 sector_t offset); 861 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 862 sector_t offset); 863 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 864 sector_t offset); 865 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 866 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 867 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 868 extern int blk_queue_dma_drain(struct request_queue *q, 869 dma_drain_needed_fn *dma_drain_needed, 870 void *buf, unsigned int size); 871 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 872 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 873 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 874 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 875 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); 876 extern void blk_queue_dma_alignment(struct request_queue *, int); 877 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 878 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 879 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 880 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 881 extern void blk_queue_flush(struct request_queue *q, unsigned int flush); 882 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 883 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 884 885 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 886 extern void blk_dump_rq_flags(struct request *, char *); 887 extern long nr_blockdev_pages(void); 888 889 bool __must_check blk_get_queue(struct request_queue *); 890 struct request_queue *blk_alloc_queue(gfp_t); 891 struct request_queue *blk_alloc_queue_node(gfp_t, int); 892 extern void blk_put_queue(struct request_queue *); 893 894 /* 895 * blk_plug permits building a queue of related requests by holding the I/O 896 * fragments for a short period. This allows merging of sequential requests 897 * into single larger request. As the requests are moved from a per-task list to 898 * the device's request_queue in a batch, this results in improved scalability 899 * as the lock contention for request_queue lock is reduced. 900 * 901 * It is ok not to disable preemption when adding the request to the plug list 902 * or when attempting a merge, because blk_schedule_flush_list() will only flush 903 * the plug list when the task sleeps by itself. For details, please see 904 * schedule() where blk_schedule_flush_plug() is called. 905 */ 906 struct blk_plug { 907 unsigned long magic; /* detect uninitialized use-cases */ 908 struct list_head list; /* requests */ 909 struct list_head cb_list; /* md requires an unplug callback */ 910 unsigned int should_sort; /* list to be sorted before flushing? */ 911 }; 912 #define BLK_MAX_REQUEST_COUNT 16 913 914 struct blk_plug_cb { 915 struct list_head list; 916 void (*callback)(struct blk_plug_cb *); 917 }; 918 919 extern void blk_start_plug(struct blk_plug *); 920 extern void blk_finish_plug(struct blk_plug *); 921 extern void blk_flush_plug_list(struct blk_plug *, bool); 922 923 static inline void blk_flush_plug(struct task_struct *tsk) 924 { 925 struct blk_plug *plug = tsk->plug; 926 927 if (plug) 928 blk_flush_plug_list(plug, false); 929 } 930 931 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 932 { 933 struct blk_plug *plug = tsk->plug; 934 935 if (plug) 936 blk_flush_plug_list(plug, true); 937 } 938 939 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 940 { 941 struct blk_plug *plug = tsk->plug; 942 943 return plug && (!list_empty(&plug->list) || !list_empty(&plug->cb_list)); 944 } 945 946 /* 947 * tag stuff 948 */ 949 #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED) 950 extern int blk_queue_start_tag(struct request_queue *, struct request *); 951 extern struct request *blk_queue_find_tag(struct request_queue *, int); 952 extern void blk_queue_end_tag(struct request_queue *, struct request *); 953 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *); 954 extern void blk_queue_free_tags(struct request_queue *); 955 extern int blk_queue_resize_tags(struct request_queue *, int); 956 extern void blk_queue_invalidate_tags(struct request_queue *); 957 extern struct blk_queue_tag *blk_init_tags(int); 958 extern void blk_free_tags(struct blk_queue_tag *); 959 960 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 961 int tag) 962 { 963 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 964 return NULL; 965 return bqt->tag_index[tag]; 966 } 967 968 #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */ 969 970 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 971 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 972 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 973 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 974 sector_t nr_sects, gfp_t gfp_mask); 975 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 976 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 977 { 978 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 979 nr_blocks << (sb->s_blocksize_bits - 9), 980 gfp_mask, flags); 981 } 982 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 983 sector_t nr_blocks, gfp_t gfp_mask) 984 { 985 return blkdev_issue_zeroout(sb->s_bdev, 986 block << (sb->s_blocksize_bits - 9), 987 nr_blocks << (sb->s_blocksize_bits - 9), 988 gfp_mask); 989 } 990 991 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 992 993 enum blk_default_limits { 994 BLK_MAX_SEGMENTS = 128, 995 BLK_SAFE_MAX_SECTORS = 255, 996 BLK_DEF_MAX_SECTORS = 1024, 997 BLK_MAX_SEGMENT_SIZE = 65536, 998 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 999 }; 1000 1001 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1002 1003 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 1004 { 1005 return q->limits.bounce_pfn; 1006 } 1007 1008 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1009 { 1010 return q->limits.seg_boundary_mask; 1011 } 1012 1013 static inline unsigned int queue_max_sectors(struct request_queue *q) 1014 { 1015 return q->limits.max_sectors; 1016 } 1017 1018 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1019 { 1020 return q->limits.max_hw_sectors; 1021 } 1022 1023 static inline unsigned short queue_max_segments(struct request_queue *q) 1024 { 1025 return q->limits.max_segments; 1026 } 1027 1028 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1029 { 1030 return q->limits.max_segment_size; 1031 } 1032 1033 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1034 { 1035 int retval = 512; 1036 1037 if (q && q->limits.logical_block_size) 1038 retval = q->limits.logical_block_size; 1039 1040 return retval; 1041 } 1042 1043 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1044 { 1045 return queue_logical_block_size(bdev_get_queue(bdev)); 1046 } 1047 1048 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1049 { 1050 return q->limits.physical_block_size; 1051 } 1052 1053 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1054 { 1055 return queue_physical_block_size(bdev_get_queue(bdev)); 1056 } 1057 1058 static inline unsigned int queue_io_min(struct request_queue *q) 1059 { 1060 return q->limits.io_min; 1061 } 1062 1063 static inline int bdev_io_min(struct block_device *bdev) 1064 { 1065 return queue_io_min(bdev_get_queue(bdev)); 1066 } 1067 1068 static inline unsigned int queue_io_opt(struct request_queue *q) 1069 { 1070 return q->limits.io_opt; 1071 } 1072 1073 static inline int bdev_io_opt(struct block_device *bdev) 1074 { 1075 return queue_io_opt(bdev_get_queue(bdev)); 1076 } 1077 1078 static inline int queue_alignment_offset(struct request_queue *q) 1079 { 1080 if (q->limits.misaligned) 1081 return -1; 1082 1083 return q->limits.alignment_offset; 1084 } 1085 1086 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1087 { 1088 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1089 unsigned int alignment = (sector << 9) & (granularity - 1); 1090 1091 return (granularity + lim->alignment_offset - alignment) 1092 & (granularity - 1); 1093 } 1094 1095 static inline int bdev_alignment_offset(struct block_device *bdev) 1096 { 1097 struct request_queue *q = bdev_get_queue(bdev); 1098 1099 if (q->limits.misaligned) 1100 return -1; 1101 1102 if (bdev != bdev->bd_contains) 1103 return bdev->bd_part->alignment_offset; 1104 1105 return q->limits.alignment_offset; 1106 } 1107 1108 static inline int queue_discard_alignment(struct request_queue *q) 1109 { 1110 if (q->limits.discard_misaligned) 1111 return -1; 1112 1113 return q->limits.discard_alignment; 1114 } 1115 1116 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1117 { 1118 unsigned int alignment = (sector << 9) & (lim->discard_granularity - 1); 1119 1120 if (!lim->max_discard_sectors) 1121 return 0; 1122 1123 return (lim->discard_granularity + lim->discard_alignment - alignment) 1124 & (lim->discard_granularity - 1); 1125 } 1126 1127 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1128 { 1129 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) 1130 return 1; 1131 1132 return 0; 1133 } 1134 1135 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1136 { 1137 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1138 } 1139 1140 static inline int queue_dma_alignment(struct request_queue *q) 1141 { 1142 return q ? q->dma_alignment : 511; 1143 } 1144 1145 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1146 unsigned int len) 1147 { 1148 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1149 return !(addr & alignment) && !(len & alignment); 1150 } 1151 1152 /* assumes size > 256 */ 1153 static inline unsigned int blksize_bits(unsigned int size) 1154 { 1155 unsigned int bits = 8; 1156 do { 1157 bits++; 1158 size >>= 1; 1159 } while (size > 256); 1160 return bits; 1161 } 1162 1163 static inline unsigned int block_size(struct block_device *bdev) 1164 { 1165 return bdev->bd_block_size; 1166 } 1167 1168 static inline bool queue_flush_queueable(struct request_queue *q) 1169 { 1170 return !q->flush_not_queueable; 1171 } 1172 1173 typedef struct {struct page *v;} Sector; 1174 1175 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1176 1177 static inline void put_dev_sector(Sector p) 1178 { 1179 page_cache_release(p.v); 1180 } 1181 1182 struct work_struct; 1183 int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); 1184 1185 #ifdef CONFIG_BLK_CGROUP 1186 /* 1187 * This should not be using sched_clock(). A real patch is in progress 1188 * to fix this up, until that is in place we need to disable preemption 1189 * around sched_clock() in this function and set_io_start_time_ns(). 1190 */ 1191 static inline void set_start_time_ns(struct request *req) 1192 { 1193 preempt_disable(); 1194 req->start_time_ns = sched_clock(); 1195 preempt_enable(); 1196 } 1197 1198 static inline void set_io_start_time_ns(struct request *req) 1199 { 1200 preempt_disable(); 1201 req->io_start_time_ns = sched_clock(); 1202 preempt_enable(); 1203 } 1204 1205 static inline uint64_t rq_start_time_ns(struct request *req) 1206 { 1207 return req->start_time_ns; 1208 } 1209 1210 static inline uint64_t rq_io_start_time_ns(struct request *req) 1211 { 1212 return req->io_start_time_ns; 1213 } 1214 #else 1215 static inline void set_start_time_ns(struct request *req) {} 1216 static inline void set_io_start_time_ns(struct request *req) {} 1217 static inline uint64_t rq_start_time_ns(struct request *req) 1218 { 1219 return 0; 1220 } 1221 static inline uint64_t rq_io_start_time_ns(struct request *req) 1222 { 1223 return 0; 1224 } 1225 #endif 1226 1227 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1228 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1229 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1230 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1231 1232 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1233 1234 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */ 1235 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */ 1236 1237 struct blk_integrity_exchg { 1238 void *prot_buf; 1239 void *data_buf; 1240 sector_t sector; 1241 unsigned int data_size; 1242 unsigned short sector_size; 1243 const char *disk_name; 1244 }; 1245 1246 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *); 1247 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *); 1248 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int); 1249 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int); 1250 1251 struct blk_integrity { 1252 integrity_gen_fn *generate_fn; 1253 integrity_vrfy_fn *verify_fn; 1254 integrity_set_tag_fn *set_tag_fn; 1255 integrity_get_tag_fn *get_tag_fn; 1256 1257 unsigned short flags; 1258 unsigned short tuple_size; 1259 unsigned short sector_size; 1260 unsigned short tag_size; 1261 1262 const char *name; 1263 1264 struct kobject kobj; 1265 }; 1266 1267 extern bool blk_integrity_is_initialized(struct gendisk *); 1268 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); 1269 extern void blk_integrity_unregister(struct gendisk *); 1270 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1271 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1272 struct scatterlist *); 1273 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1274 extern int blk_integrity_merge_rq(struct request_queue *, struct request *, 1275 struct request *); 1276 extern int blk_integrity_merge_bio(struct request_queue *, struct request *, 1277 struct bio *); 1278 1279 static inline 1280 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1281 { 1282 return bdev->bd_disk->integrity; 1283 } 1284 1285 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1286 { 1287 return disk->integrity; 1288 } 1289 1290 static inline int blk_integrity_rq(struct request *rq) 1291 { 1292 if (rq->bio == NULL) 1293 return 0; 1294 1295 return bio_integrity(rq->bio); 1296 } 1297 1298 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1299 unsigned int segs) 1300 { 1301 q->limits.max_integrity_segments = segs; 1302 } 1303 1304 static inline unsigned short 1305 queue_max_integrity_segments(struct request_queue *q) 1306 { 1307 return q->limits.max_integrity_segments; 1308 } 1309 1310 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1311 1312 struct bio; 1313 struct block_device; 1314 struct gendisk; 1315 struct blk_integrity; 1316 1317 static inline int blk_integrity_rq(struct request *rq) 1318 { 1319 return 0; 1320 } 1321 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1322 struct bio *b) 1323 { 1324 return 0; 1325 } 1326 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1327 struct bio *b, 1328 struct scatterlist *s) 1329 { 1330 return 0; 1331 } 1332 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1333 { 1334 return 0; 1335 } 1336 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1337 { 1338 return NULL; 1339 } 1340 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1341 { 1342 return 0; 1343 } 1344 static inline int blk_integrity_register(struct gendisk *d, 1345 struct blk_integrity *b) 1346 { 1347 return 0; 1348 } 1349 static inline void blk_integrity_unregister(struct gendisk *d) 1350 { 1351 } 1352 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1353 unsigned int segs) 1354 { 1355 } 1356 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1357 { 1358 return 0; 1359 } 1360 static inline int blk_integrity_merge_rq(struct request_queue *rq, 1361 struct request *r1, 1362 struct request *r2) 1363 { 1364 return 0; 1365 } 1366 static inline int blk_integrity_merge_bio(struct request_queue *rq, 1367 struct request *r, 1368 struct bio *b) 1369 { 1370 return 0; 1371 } 1372 static inline bool blk_integrity_is_initialized(struct gendisk *g) 1373 { 1374 return 0; 1375 } 1376 1377 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1378 1379 struct block_device_operations { 1380 int (*open) (struct block_device *, fmode_t); 1381 int (*release) (struct gendisk *, fmode_t); 1382 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1383 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1384 int (*direct_access) (struct block_device *, sector_t, 1385 void **, unsigned long *); 1386 unsigned int (*check_events) (struct gendisk *disk, 1387 unsigned int clearing); 1388 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1389 int (*media_changed) (struct gendisk *); 1390 void (*unlock_native_capacity) (struct gendisk *); 1391 int (*revalidate_disk) (struct gendisk *); 1392 int (*getgeo)(struct block_device *, struct hd_geometry *); 1393 /* this callback is with swap_lock and sometimes page table lock held */ 1394 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1395 struct module *owner; 1396 }; 1397 1398 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1399 unsigned long); 1400 #else /* CONFIG_BLOCK */ 1401 /* 1402 * stubs for when the block layer is configured out 1403 */ 1404 #define buffer_heads_over_limit 0 1405 1406 static inline long nr_blockdev_pages(void) 1407 { 1408 return 0; 1409 } 1410 1411 struct blk_plug { 1412 }; 1413 1414 static inline void blk_start_plug(struct blk_plug *plug) 1415 { 1416 } 1417 1418 static inline void blk_finish_plug(struct blk_plug *plug) 1419 { 1420 } 1421 1422 static inline void blk_flush_plug(struct task_struct *task) 1423 { 1424 } 1425 1426 static inline void blk_schedule_flush_plug(struct task_struct *task) 1427 { 1428 } 1429 1430 1431 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1432 { 1433 return false; 1434 } 1435 1436 #endif /* CONFIG_BLOCK */ 1437 1438 #endif 1439