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/module.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 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 34 #define BLKDEV_MIN_RQ 4 35 #define BLKDEV_MAX_RQ 128 /* Default maximum */ 36 37 struct request; 38 typedef void (rq_end_io_fn)(struct request *, int); 39 40 struct request_list { 41 /* 42 * count[], starved[], and wait[] are indexed by 43 * BLK_RW_SYNC/BLK_RW_ASYNC 44 */ 45 int count[2]; 46 int starved[2]; 47 int elvpriv; 48 mempool_t *rq_pool; 49 wait_queue_head_t wait[2]; 50 }; 51 52 /* 53 * request command types 54 */ 55 enum rq_cmd_type_bits { 56 REQ_TYPE_FS = 1, /* fs request */ 57 REQ_TYPE_BLOCK_PC, /* scsi command */ 58 REQ_TYPE_SENSE, /* sense request */ 59 REQ_TYPE_PM_SUSPEND, /* suspend request */ 60 REQ_TYPE_PM_RESUME, /* resume request */ 61 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */ 62 REQ_TYPE_SPECIAL, /* driver defined type */ 63 /* 64 * for ATA/ATAPI devices. this really doesn't belong here, ide should 65 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver 66 * private REQ_LB opcodes to differentiate what type of request this is 67 */ 68 REQ_TYPE_ATA_TASKFILE, 69 REQ_TYPE_ATA_PC, 70 }; 71 72 #define BLK_MAX_CDB 16 73 74 /* 75 * try to put the fields that are referenced together in the same cacheline. 76 * if you modify this structure, be sure to check block/blk-core.c:rq_init() 77 * as well! 78 */ 79 struct request { 80 struct list_head queuelist; 81 struct call_single_data csd; 82 83 struct request_queue *q; 84 85 unsigned int cmd_flags; 86 enum rq_cmd_type_bits cmd_type; 87 unsigned long atomic_flags; 88 89 int cpu; 90 91 /* the following two fields are internal, NEVER access directly */ 92 unsigned int __data_len; /* total data len */ 93 sector_t __sector; /* sector cursor */ 94 95 struct bio *bio; 96 struct bio *biotail; 97 98 struct hlist_node hash; /* merge hash */ 99 /* 100 * The rb_node is only used inside the io scheduler, requests 101 * are pruned when moved to the dispatch queue. So let the 102 * completion_data share space with the rb_node. 103 */ 104 union { 105 struct rb_node rb_node; /* sort/lookup */ 106 void *completion_data; 107 }; 108 109 /* 110 * Three pointers are available for the IO schedulers, if they need 111 * more they have to dynamically allocate it. 112 */ 113 void *elevator_private; 114 void *elevator_private2; 115 void *elevator_private3; 116 117 struct gendisk *rq_disk; 118 unsigned long start_time; 119 #ifdef CONFIG_BLK_CGROUP 120 unsigned long long start_time_ns; 121 unsigned long long io_start_time_ns; /* when passed to hardware */ 122 #endif 123 /* Number of scatter-gather DMA addr+len pairs after 124 * physical address coalescing is performed. 125 */ 126 unsigned short nr_phys_segments; 127 128 unsigned short ioprio; 129 130 int ref_count; 131 132 void *special; /* opaque pointer available for LLD use */ 133 char *buffer; /* kaddr of the current segment if available */ 134 135 int tag; 136 int errors; 137 138 /* 139 * when request is used as a packet command carrier 140 */ 141 unsigned char __cmd[BLK_MAX_CDB]; 142 unsigned char *cmd; 143 unsigned short cmd_len; 144 145 unsigned int extra_len; /* length of alignment and padding */ 146 unsigned int sense_len; 147 unsigned int resid_len; /* residual count */ 148 void *sense; 149 150 unsigned long deadline; 151 struct list_head timeout_list; 152 unsigned int timeout; 153 int retries; 154 155 /* 156 * completion callback. 157 */ 158 rq_end_io_fn *end_io; 159 void *end_io_data; 160 161 /* for bidi */ 162 struct request *next_rq; 163 }; 164 165 static inline unsigned short req_get_ioprio(struct request *req) 166 { 167 return req->ioprio; 168 } 169 170 /* 171 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME 172 * requests. Some step values could eventually be made generic. 173 */ 174 struct request_pm_state 175 { 176 /* PM state machine step value, currently driver specific */ 177 int pm_step; 178 /* requested PM state value (S1, S2, S3, S4, ...) */ 179 u32 pm_state; 180 void* data; /* for driver use */ 181 }; 182 183 #include <linux/elevator.h> 184 185 typedef void (request_fn_proc) (struct request_queue *q); 186 typedef int (make_request_fn) (struct request_queue *q, struct bio *bio); 187 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 188 typedef void (unprep_rq_fn) (struct request_queue *, struct request *); 189 typedef void (unplug_fn) (struct request_queue *); 190 191 struct bio_vec; 192 struct bvec_merge_data { 193 struct block_device *bi_bdev; 194 sector_t bi_sector; 195 unsigned bi_size; 196 unsigned long bi_rw; 197 }; 198 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *, 199 struct bio_vec *); 200 typedef void (softirq_done_fn)(struct request *); 201 typedef int (dma_drain_needed_fn)(struct request *); 202 typedef int (lld_busy_fn) (struct request_queue *q); 203 204 enum blk_eh_timer_return { 205 BLK_EH_NOT_HANDLED, 206 BLK_EH_HANDLED, 207 BLK_EH_RESET_TIMER, 208 }; 209 210 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 211 212 enum blk_queue_state { 213 Queue_down, 214 Queue_up, 215 }; 216 217 struct blk_queue_tag { 218 struct request **tag_index; /* map of busy tags */ 219 unsigned long *tag_map; /* bit map of free/busy tags */ 220 int busy; /* current depth */ 221 int max_depth; /* what we will send to device */ 222 int real_max_depth; /* what the array can hold */ 223 atomic_t refcnt; /* map can be shared */ 224 }; 225 226 #define BLK_SCSI_MAX_CMDS (256) 227 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 228 229 struct queue_limits { 230 unsigned long bounce_pfn; 231 unsigned long seg_boundary_mask; 232 233 unsigned int max_hw_sectors; 234 unsigned int max_sectors; 235 unsigned int max_segment_size; 236 unsigned int physical_block_size; 237 unsigned int alignment_offset; 238 unsigned int io_min; 239 unsigned int io_opt; 240 unsigned int max_discard_sectors; 241 unsigned int discard_granularity; 242 unsigned int discard_alignment; 243 244 unsigned short logical_block_size; 245 unsigned short max_segments; 246 247 unsigned char misaligned; 248 unsigned char discard_misaligned; 249 unsigned char no_cluster; 250 signed char discard_zeroes_data; 251 }; 252 253 struct request_queue 254 { 255 /* 256 * Together with queue_head for cacheline sharing 257 */ 258 struct list_head queue_head; 259 struct request *last_merge; 260 struct elevator_queue *elevator; 261 262 /* 263 * the queue request freelist, one for reads and one for writes 264 */ 265 struct request_list rq; 266 267 request_fn_proc *request_fn; 268 make_request_fn *make_request_fn; 269 prep_rq_fn *prep_rq_fn; 270 unprep_rq_fn *unprep_rq_fn; 271 unplug_fn *unplug_fn; 272 merge_bvec_fn *merge_bvec_fn; 273 softirq_done_fn *softirq_done_fn; 274 rq_timed_out_fn *rq_timed_out_fn; 275 dma_drain_needed_fn *dma_drain_needed; 276 lld_busy_fn *lld_busy_fn; 277 278 /* 279 * Dispatch queue sorting 280 */ 281 sector_t end_sector; 282 struct request *boundary_rq; 283 284 /* 285 * Auto-unplugging state 286 */ 287 struct timer_list unplug_timer; 288 int unplug_thresh; /* After this many requests */ 289 unsigned long unplug_delay; /* After this many jiffies */ 290 struct work_struct unplug_work; 291 292 struct backing_dev_info backing_dev_info; 293 294 /* 295 * The queue owner gets to use this for whatever they like. 296 * ll_rw_blk doesn't touch it. 297 */ 298 void *queuedata; 299 300 /* 301 * queue needs bounce pages for pages above this limit 302 */ 303 gfp_t bounce_gfp; 304 305 /* 306 * various queue flags, see QUEUE_* below 307 */ 308 unsigned long queue_flags; 309 310 /* 311 * protects queue structures from reentrancy. ->__queue_lock should 312 * _never_ be used directly, it is queue private. always use 313 * ->queue_lock. 314 */ 315 spinlock_t __queue_lock; 316 spinlock_t *queue_lock; 317 318 /* 319 * queue kobject 320 */ 321 struct kobject kobj; 322 323 /* 324 * queue settings 325 */ 326 unsigned long nr_requests; /* Max # of requests */ 327 unsigned int nr_congestion_on; 328 unsigned int nr_congestion_off; 329 unsigned int nr_batching; 330 331 void *dma_drain_buffer; 332 unsigned int dma_drain_size; 333 unsigned int dma_pad_mask; 334 unsigned int dma_alignment; 335 336 struct blk_queue_tag *queue_tags; 337 struct list_head tag_busy_list; 338 339 unsigned int nr_sorted; 340 unsigned int in_flight[2]; 341 342 unsigned int rq_timeout; 343 struct timer_list timeout; 344 struct list_head timeout_list; 345 346 struct queue_limits limits; 347 348 /* 349 * sg stuff 350 */ 351 unsigned int sg_timeout; 352 unsigned int sg_reserved_size; 353 int node; 354 #ifdef CONFIG_BLK_DEV_IO_TRACE 355 struct blk_trace *blk_trace; 356 #endif 357 /* 358 * reserved for flush operations 359 */ 360 unsigned int ordered, next_ordered, ordseq; 361 int orderr, ordcolor; 362 struct request pre_flush_rq, bar_rq, post_flush_rq; 363 struct request *orig_bar_rq; 364 365 struct mutex sysfs_lock; 366 367 #if defined(CONFIG_BLK_DEV_BSG) 368 struct bsg_class_device bsg_dev; 369 #endif 370 }; 371 372 #define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */ 373 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 374 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 375 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 376 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 377 #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ 378 #define QUEUE_FLAG_REENTER 6 /* Re-entrancy avoidance */ 379 #define QUEUE_FLAG_PLUGGED 7 /* queue is plugged */ 380 #define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */ 381 #define QUEUE_FLAG_BIDI 9 /* queue supports bidi requests */ 382 #define QUEUE_FLAG_NOMERGES 10 /* disable merge attempts */ 383 #define QUEUE_FLAG_SAME_COMP 11 /* force complete on same CPU */ 384 #define QUEUE_FLAG_FAIL_IO 12 /* fake timeout */ 385 #define QUEUE_FLAG_STACKABLE 13 /* supports request stacking */ 386 #define QUEUE_FLAG_NONROT 14 /* non-rotational device (SSD) */ 387 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 388 #define QUEUE_FLAG_IO_STAT 15 /* do IO stats */ 389 #define QUEUE_FLAG_DISCARD 16 /* supports DISCARD */ 390 #define QUEUE_FLAG_NOXMERGES 17 /* No extended merges */ 391 #define QUEUE_FLAG_ADD_RANDOM 18 /* Contributes to random pool */ 392 #define QUEUE_FLAG_SECDISCARD 19 /* supports SECDISCARD */ 393 394 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 395 (1 << QUEUE_FLAG_CLUSTER) | \ 396 (1 << QUEUE_FLAG_STACKABLE) | \ 397 (1 << QUEUE_FLAG_SAME_COMP) | \ 398 (1 << QUEUE_FLAG_ADD_RANDOM)) 399 400 static inline int queue_is_locked(struct request_queue *q) 401 { 402 #ifdef CONFIG_SMP 403 spinlock_t *lock = q->queue_lock; 404 return lock && spin_is_locked(lock); 405 #else 406 return 1; 407 #endif 408 } 409 410 static inline void queue_flag_set_unlocked(unsigned int flag, 411 struct request_queue *q) 412 { 413 __set_bit(flag, &q->queue_flags); 414 } 415 416 static inline int queue_flag_test_and_clear(unsigned int flag, 417 struct request_queue *q) 418 { 419 WARN_ON_ONCE(!queue_is_locked(q)); 420 421 if (test_bit(flag, &q->queue_flags)) { 422 __clear_bit(flag, &q->queue_flags); 423 return 1; 424 } 425 426 return 0; 427 } 428 429 static inline int queue_flag_test_and_set(unsigned int flag, 430 struct request_queue *q) 431 { 432 WARN_ON_ONCE(!queue_is_locked(q)); 433 434 if (!test_bit(flag, &q->queue_flags)) { 435 __set_bit(flag, &q->queue_flags); 436 return 0; 437 } 438 439 return 1; 440 } 441 442 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 443 { 444 WARN_ON_ONCE(!queue_is_locked(q)); 445 __set_bit(flag, &q->queue_flags); 446 } 447 448 static inline void queue_flag_clear_unlocked(unsigned int flag, 449 struct request_queue *q) 450 { 451 __clear_bit(flag, &q->queue_flags); 452 } 453 454 static inline int queue_in_flight(struct request_queue *q) 455 { 456 return q->in_flight[0] + q->in_flight[1]; 457 } 458 459 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 460 { 461 WARN_ON_ONCE(!queue_is_locked(q)); 462 __clear_bit(flag, &q->queue_flags); 463 } 464 465 enum { 466 /* 467 * Hardbarrier is supported with one of the following methods. 468 * 469 * NONE : hardbarrier unsupported 470 * DRAIN : ordering by draining is enough 471 * DRAIN_FLUSH : ordering by draining w/ pre and post flushes 472 * DRAIN_FUA : ordering by draining w/ pre flush and FUA write 473 * TAG : ordering by tag is enough 474 * TAG_FLUSH : ordering by tag w/ pre and post flushes 475 * TAG_FUA : ordering by tag w/ pre flush and FUA write 476 */ 477 QUEUE_ORDERED_BY_DRAIN = 0x01, 478 QUEUE_ORDERED_BY_TAG = 0x02, 479 QUEUE_ORDERED_DO_PREFLUSH = 0x10, 480 QUEUE_ORDERED_DO_BAR = 0x20, 481 QUEUE_ORDERED_DO_POSTFLUSH = 0x40, 482 QUEUE_ORDERED_DO_FUA = 0x80, 483 484 QUEUE_ORDERED_NONE = 0x00, 485 486 QUEUE_ORDERED_DRAIN = QUEUE_ORDERED_BY_DRAIN | 487 QUEUE_ORDERED_DO_BAR, 488 QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN | 489 QUEUE_ORDERED_DO_PREFLUSH | 490 QUEUE_ORDERED_DO_POSTFLUSH, 491 QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN | 492 QUEUE_ORDERED_DO_PREFLUSH | 493 QUEUE_ORDERED_DO_FUA, 494 495 QUEUE_ORDERED_TAG = QUEUE_ORDERED_BY_TAG | 496 QUEUE_ORDERED_DO_BAR, 497 QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG | 498 QUEUE_ORDERED_DO_PREFLUSH | 499 QUEUE_ORDERED_DO_POSTFLUSH, 500 QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG | 501 QUEUE_ORDERED_DO_PREFLUSH | 502 QUEUE_ORDERED_DO_FUA, 503 504 /* 505 * Ordered operation sequence 506 */ 507 QUEUE_ORDSEQ_STARTED = 0x01, /* flushing in progress */ 508 QUEUE_ORDSEQ_DRAIN = 0x02, /* waiting for the queue to be drained */ 509 QUEUE_ORDSEQ_PREFLUSH = 0x04, /* pre-flushing in progress */ 510 QUEUE_ORDSEQ_BAR = 0x08, /* original barrier req in progress */ 511 QUEUE_ORDSEQ_POSTFLUSH = 0x10, /* post-flushing in progress */ 512 QUEUE_ORDSEQ_DONE = 0x20, 513 }; 514 515 #define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags) 516 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 517 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 518 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 519 #define blk_queue_noxmerges(q) \ 520 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 521 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 522 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 523 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 524 #define blk_queue_flushing(q) ((q)->ordseq) 525 #define blk_queue_stackable(q) \ 526 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 527 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 528 #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \ 529 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags)) 530 531 #define blk_noretry_request(rq) \ 532 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 533 REQ_FAILFAST_DRIVER)) 534 535 #define blk_account_rq(rq) \ 536 (((rq)->cmd_flags & REQ_STARTED) && \ 537 ((rq)->cmd_type == REQ_TYPE_FS || \ 538 ((rq)->cmd_flags & REQ_DISCARD))) 539 540 #define blk_pm_request(rq) \ 541 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \ 542 (rq)->cmd_type == REQ_TYPE_PM_RESUME) 543 544 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 545 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 546 /* rq->queuelist of dequeued request must be list_empty() */ 547 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 548 549 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 550 551 #define rq_data_dir(rq) ((rq)->cmd_flags & 1) 552 553 /* 554 * We regard a request as sync, if either a read or a sync write 555 */ 556 static inline bool rw_is_sync(unsigned int rw_flags) 557 { 558 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC); 559 } 560 561 static inline bool rq_is_sync(struct request *rq) 562 { 563 return rw_is_sync(rq->cmd_flags); 564 } 565 566 static inline int blk_queue_full(struct request_queue *q, int sync) 567 { 568 if (sync) 569 return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags); 570 return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags); 571 } 572 573 static inline void blk_set_queue_full(struct request_queue *q, int sync) 574 { 575 if (sync) 576 queue_flag_set(QUEUE_FLAG_SYNCFULL, q); 577 else 578 queue_flag_set(QUEUE_FLAG_ASYNCFULL, q); 579 } 580 581 static inline void blk_clear_queue_full(struct request_queue *q, int sync) 582 { 583 if (sync) 584 queue_flag_clear(QUEUE_FLAG_SYNCFULL, q); 585 else 586 queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q); 587 } 588 589 590 /* 591 * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may 592 * it already be started by driver. 593 */ 594 #define RQ_NOMERGE_FLAGS \ 595 (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER) 596 #define rq_mergeable(rq) \ 597 (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \ 598 (((rq)->cmd_flags & REQ_DISCARD) || \ 599 (rq)->cmd_type == REQ_TYPE_FS)) 600 601 /* 602 * q->prep_rq_fn return values 603 */ 604 #define BLKPREP_OK 0 /* serve it */ 605 #define BLKPREP_KILL 1 /* fatal error, kill */ 606 #define BLKPREP_DEFER 2 /* leave on queue */ 607 608 extern unsigned long blk_max_low_pfn, blk_max_pfn; 609 610 /* 611 * standard bounce addresses: 612 * 613 * BLK_BOUNCE_HIGH : bounce all highmem pages 614 * BLK_BOUNCE_ANY : don't bounce anything 615 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 616 */ 617 618 #if BITS_PER_LONG == 32 619 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 620 #else 621 #define BLK_BOUNCE_HIGH -1ULL 622 #endif 623 #define BLK_BOUNCE_ANY (-1ULL) 624 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 625 626 /* 627 * default timeout for SG_IO if none specified 628 */ 629 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 630 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 631 632 #ifdef CONFIG_BOUNCE 633 extern int init_emergency_isa_pool(void); 634 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 635 #else 636 static inline int init_emergency_isa_pool(void) 637 { 638 return 0; 639 } 640 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 641 { 642 } 643 #endif /* CONFIG_MMU */ 644 645 struct rq_map_data { 646 struct page **pages; 647 int page_order; 648 int nr_entries; 649 unsigned long offset; 650 int null_mapped; 651 int from_user; 652 }; 653 654 struct req_iterator { 655 int i; 656 struct bio *bio; 657 }; 658 659 /* This should not be used directly - use rq_for_each_segment */ 660 #define for_each_bio(_bio) \ 661 for (; _bio; _bio = _bio->bi_next) 662 #define __rq_for_each_bio(_bio, rq) \ 663 if ((rq->bio)) \ 664 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 665 666 #define rq_for_each_segment(bvl, _rq, _iter) \ 667 __rq_for_each_bio(_iter.bio, _rq) \ 668 bio_for_each_segment(bvl, _iter.bio, _iter.i) 669 670 #define rq_iter_last(rq, _iter) \ 671 (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1) 672 673 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 674 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 675 #endif 676 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 677 extern void rq_flush_dcache_pages(struct request *rq); 678 #else 679 static inline void rq_flush_dcache_pages(struct request *rq) 680 { 681 } 682 #endif 683 684 extern int blk_register_queue(struct gendisk *disk); 685 extern void blk_unregister_queue(struct gendisk *disk); 686 extern void register_disk(struct gendisk *dev); 687 extern void generic_make_request(struct bio *bio); 688 extern void blk_rq_init(struct request_queue *q, struct request *rq); 689 extern void blk_put_request(struct request *); 690 extern void __blk_put_request(struct request_queue *, struct request *); 691 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 692 extern struct request *blk_make_request(struct request_queue *, struct bio *, 693 gfp_t); 694 extern void blk_insert_request(struct request_queue *, struct request *, int, void *); 695 extern void blk_requeue_request(struct request_queue *, struct request *); 696 extern void blk_add_request_payload(struct request *rq, struct page *page, 697 unsigned int len); 698 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); 699 extern int blk_lld_busy(struct request_queue *q); 700 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 701 struct bio_set *bs, gfp_t gfp_mask, 702 int (*bio_ctr)(struct bio *, struct bio *, void *), 703 void *data); 704 extern void blk_rq_unprep_clone(struct request *rq); 705 extern int blk_insert_cloned_request(struct request_queue *q, 706 struct request *rq); 707 extern void blk_plug_device(struct request_queue *); 708 extern void blk_plug_device_unlocked(struct request_queue *); 709 extern int blk_remove_plug(struct request_queue *); 710 extern void blk_recount_segments(struct request_queue *, struct bio *); 711 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 712 unsigned int, void __user *); 713 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 714 struct scsi_ioctl_command __user *); 715 716 /* 717 * A queue has just exitted congestion. Note this in the global counter of 718 * congested queues, and wake up anyone who was waiting for requests to be 719 * put back. 720 */ 721 static inline void blk_clear_queue_congested(struct request_queue *q, int sync) 722 { 723 clear_bdi_congested(&q->backing_dev_info, sync); 724 } 725 726 /* 727 * A queue has just entered congestion. Flag that in the queue's VM-visible 728 * state flags and increment the global gounter of congested queues. 729 */ 730 static inline void blk_set_queue_congested(struct request_queue *q, int sync) 731 { 732 set_bdi_congested(&q->backing_dev_info, sync); 733 } 734 735 extern void blk_start_queue(struct request_queue *q); 736 extern void blk_stop_queue(struct request_queue *q); 737 extern void blk_sync_queue(struct request_queue *q); 738 extern void __blk_stop_queue(struct request_queue *q); 739 extern void __blk_run_queue(struct request_queue *); 740 extern void blk_run_queue(struct request_queue *); 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 extern void blk_unplug(struct request_queue *q); 754 755 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 756 { 757 return bdev->bd_disk->queue; 758 } 759 760 /* 761 * blk_rq_pos() : the current sector 762 * blk_rq_bytes() : bytes left in the entire request 763 * blk_rq_cur_bytes() : bytes left in the current segment 764 * blk_rq_err_bytes() : bytes left till the next error boundary 765 * blk_rq_sectors() : sectors left in the entire request 766 * blk_rq_cur_sectors() : sectors left in the current segment 767 */ 768 static inline sector_t blk_rq_pos(const struct request *rq) 769 { 770 return rq->__sector; 771 } 772 773 static inline unsigned int blk_rq_bytes(const struct request *rq) 774 { 775 return rq->__data_len; 776 } 777 778 static inline int blk_rq_cur_bytes(const struct request *rq) 779 { 780 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 781 } 782 783 extern unsigned int blk_rq_err_bytes(const struct request *rq); 784 785 static inline unsigned int blk_rq_sectors(const struct request *rq) 786 { 787 return blk_rq_bytes(rq) >> 9; 788 } 789 790 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 791 { 792 return blk_rq_cur_bytes(rq) >> 9; 793 } 794 795 /* 796 * Request issue related functions. 797 */ 798 extern struct request *blk_peek_request(struct request_queue *q); 799 extern void blk_start_request(struct request *rq); 800 extern struct request *blk_fetch_request(struct request_queue *q); 801 802 /* 803 * Request completion related functions. 804 * 805 * blk_update_request() completes given number of bytes and updates 806 * the request without completing it. 807 * 808 * blk_end_request() and friends. __blk_end_request() must be called 809 * with the request queue spinlock acquired. 810 * 811 * Several drivers define their own end_request and call 812 * blk_end_request() for parts of the original function. 813 * This prevents code duplication in drivers. 814 */ 815 extern bool blk_update_request(struct request *rq, int error, 816 unsigned int nr_bytes); 817 extern bool blk_end_request(struct request *rq, int error, 818 unsigned int nr_bytes); 819 extern void blk_end_request_all(struct request *rq, int error); 820 extern bool blk_end_request_cur(struct request *rq, int error); 821 extern bool blk_end_request_err(struct request *rq, int error); 822 extern bool __blk_end_request(struct request *rq, int error, 823 unsigned int nr_bytes); 824 extern void __blk_end_request_all(struct request *rq, int error); 825 extern bool __blk_end_request_cur(struct request *rq, int error); 826 extern bool __blk_end_request_err(struct request *rq, int error); 827 828 extern void blk_complete_request(struct request *); 829 extern void __blk_complete_request(struct request *); 830 extern void blk_abort_request(struct request *); 831 extern void blk_abort_queue(struct request_queue *); 832 extern void blk_unprep_request(struct request *); 833 834 /* 835 * Access functions for manipulating queue properties 836 */ 837 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 838 spinlock_t *lock, int node_id); 839 extern struct request_queue *blk_init_allocated_queue_node(struct request_queue *, 840 request_fn_proc *, 841 spinlock_t *, int node_id); 842 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 843 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 844 request_fn_proc *, spinlock_t *); 845 extern void blk_cleanup_queue(struct request_queue *); 846 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 847 extern void blk_queue_bounce_limit(struct request_queue *, u64); 848 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 849 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 850 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 851 extern void blk_queue_max_discard_sectors(struct request_queue *q, 852 unsigned int max_discard_sectors); 853 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 854 extern void blk_queue_physical_block_size(struct request_queue *, unsigned short); 855 extern void blk_queue_alignment_offset(struct request_queue *q, 856 unsigned int alignment); 857 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 858 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 859 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 860 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 861 extern void blk_set_default_limits(struct queue_limits *lim); 862 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 863 sector_t offset); 864 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 865 sector_t offset); 866 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 867 sector_t offset); 868 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 869 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 870 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 871 extern int blk_queue_dma_drain(struct request_queue *q, 872 dma_drain_needed_fn *dma_drain_needed, 873 void *buf, unsigned int size); 874 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 875 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 876 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 877 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 878 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); 879 extern void blk_queue_dma_alignment(struct request_queue *, int); 880 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 881 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 882 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 883 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 884 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 885 extern int blk_queue_ordered(struct request_queue *, unsigned); 886 extern bool blk_do_ordered(struct request_queue *, struct request **); 887 extern unsigned blk_ordered_cur_seq(struct request_queue *); 888 extern unsigned blk_ordered_req_seq(struct request *); 889 extern bool blk_ordered_complete_seq(struct request_queue *, unsigned, int); 890 891 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 892 extern void blk_dump_rq_flags(struct request *, char *); 893 extern void generic_unplug_device(struct request_queue *); 894 extern long nr_blockdev_pages(void); 895 896 int blk_get_queue(struct request_queue *); 897 struct request_queue *blk_alloc_queue(gfp_t); 898 struct request_queue *blk_alloc_queue_node(gfp_t, int); 899 extern void blk_put_queue(struct request_queue *); 900 901 /* 902 * tag stuff 903 */ 904 #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED) 905 extern int blk_queue_start_tag(struct request_queue *, struct request *); 906 extern struct request *blk_queue_find_tag(struct request_queue *, int); 907 extern void blk_queue_end_tag(struct request_queue *, struct request *); 908 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *); 909 extern void blk_queue_free_tags(struct request_queue *); 910 extern int blk_queue_resize_tags(struct request_queue *, int); 911 extern void blk_queue_invalidate_tags(struct request_queue *); 912 extern struct blk_queue_tag *blk_init_tags(int); 913 extern void blk_free_tags(struct blk_queue_tag *); 914 915 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 916 int tag) 917 { 918 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 919 return NULL; 920 return bqt->tag_index[tag]; 921 } 922 enum{ 923 BLKDEV_WAIT, /* wait for completion */ 924 BLKDEV_BARRIER, /* issue request with barrier */ 925 BLKDEV_SECURE, /* secure discard */ 926 }; 927 #define BLKDEV_IFL_WAIT (1 << BLKDEV_WAIT) 928 #define BLKDEV_IFL_BARRIER (1 << BLKDEV_BARRIER) 929 #define BLKDEV_IFL_SECURE (1 << BLKDEV_SECURE) 930 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *, 931 unsigned long); 932 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 933 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 934 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 935 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 936 static inline int sb_issue_discard(struct super_block *sb, 937 sector_t block, sector_t nr_blocks) 938 { 939 block <<= (sb->s_blocksize_bits - 9); 940 nr_blocks <<= (sb->s_blocksize_bits - 9); 941 return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_NOFS, 942 BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER); 943 } 944 945 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 946 947 enum blk_default_limits { 948 BLK_MAX_SEGMENTS = 128, 949 BLK_SAFE_MAX_SECTORS = 255, 950 BLK_DEF_MAX_SECTORS = 1024, 951 BLK_MAX_SEGMENT_SIZE = 65536, 952 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 953 }; 954 955 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 956 957 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 958 { 959 return q->limits.bounce_pfn; 960 } 961 962 static inline unsigned long queue_segment_boundary(struct request_queue *q) 963 { 964 return q->limits.seg_boundary_mask; 965 } 966 967 static inline unsigned int queue_max_sectors(struct request_queue *q) 968 { 969 return q->limits.max_sectors; 970 } 971 972 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 973 { 974 return q->limits.max_hw_sectors; 975 } 976 977 static inline unsigned short queue_max_segments(struct request_queue *q) 978 { 979 return q->limits.max_segments; 980 } 981 982 static inline unsigned int queue_max_segment_size(struct request_queue *q) 983 { 984 return q->limits.max_segment_size; 985 } 986 987 static inline unsigned short queue_logical_block_size(struct request_queue *q) 988 { 989 int retval = 512; 990 991 if (q && q->limits.logical_block_size) 992 retval = q->limits.logical_block_size; 993 994 return retval; 995 } 996 997 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 998 { 999 return queue_logical_block_size(bdev_get_queue(bdev)); 1000 } 1001 1002 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1003 { 1004 return q->limits.physical_block_size; 1005 } 1006 1007 static inline int bdev_physical_block_size(struct block_device *bdev) 1008 { 1009 return queue_physical_block_size(bdev_get_queue(bdev)); 1010 } 1011 1012 static inline unsigned int queue_io_min(struct request_queue *q) 1013 { 1014 return q->limits.io_min; 1015 } 1016 1017 static inline int bdev_io_min(struct block_device *bdev) 1018 { 1019 return queue_io_min(bdev_get_queue(bdev)); 1020 } 1021 1022 static inline unsigned int queue_io_opt(struct request_queue *q) 1023 { 1024 return q->limits.io_opt; 1025 } 1026 1027 static inline int bdev_io_opt(struct block_device *bdev) 1028 { 1029 return queue_io_opt(bdev_get_queue(bdev)); 1030 } 1031 1032 static inline int queue_alignment_offset(struct request_queue *q) 1033 { 1034 if (q->limits.misaligned) 1035 return -1; 1036 1037 return q->limits.alignment_offset; 1038 } 1039 1040 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1041 { 1042 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1043 unsigned int alignment = (sector << 9) & (granularity - 1); 1044 1045 return (granularity + lim->alignment_offset - alignment) 1046 & (granularity - 1); 1047 } 1048 1049 static inline int bdev_alignment_offset(struct block_device *bdev) 1050 { 1051 struct request_queue *q = bdev_get_queue(bdev); 1052 1053 if (q->limits.misaligned) 1054 return -1; 1055 1056 if (bdev != bdev->bd_contains) 1057 return bdev->bd_part->alignment_offset; 1058 1059 return q->limits.alignment_offset; 1060 } 1061 1062 static inline int queue_discard_alignment(struct request_queue *q) 1063 { 1064 if (q->limits.discard_misaligned) 1065 return -1; 1066 1067 return q->limits.discard_alignment; 1068 } 1069 1070 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1071 { 1072 unsigned int alignment = (sector << 9) & (lim->discard_granularity - 1); 1073 1074 return (lim->discard_granularity + lim->discard_alignment - alignment) 1075 & (lim->discard_granularity - 1); 1076 } 1077 1078 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1079 { 1080 if (q->limits.discard_zeroes_data == 1) 1081 return 1; 1082 1083 return 0; 1084 } 1085 1086 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1087 { 1088 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1089 } 1090 1091 static inline int queue_dma_alignment(struct request_queue *q) 1092 { 1093 return q ? q->dma_alignment : 511; 1094 } 1095 1096 static inline int blk_rq_aligned(struct request_queue *q, void *addr, 1097 unsigned int len) 1098 { 1099 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1100 return !((unsigned long)addr & alignment) && !(len & alignment); 1101 } 1102 1103 /* assumes size > 256 */ 1104 static inline unsigned int blksize_bits(unsigned int size) 1105 { 1106 unsigned int bits = 8; 1107 do { 1108 bits++; 1109 size >>= 1; 1110 } while (size > 256); 1111 return bits; 1112 } 1113 1114 static inline unsigned int block_size(struct block_device *bdev) 1115 { 1116 return bdev->bd_block_size; 1117 } 1118 1119 typedef struct {struct page *v;} Sector; 1120 1121 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1122 1123 static inline void put_dev_sector(Sector p) 1124 { 1125 page_cache_release(p.v); 1126 } 1127 1128 struct work_struct; 1129 int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); 1130 1131 #ifdef CONFIG_BLK_CGROUP 1132 /* 1133 * This should not be using sched_clock(). A real patch is in progress 1134 * to fix this up, until that is in place we need to disable preemption 1135 * around sched_clock() in this function and set_io_start_time_ns(). 1136 */ 1137 static inline void set_start_time_ns(struct request *req) 1138 { 1139 preempt_disable(); 1140 req->start_time_ns = sched_clock(); 1141 preempt_enable(); 1142 } 1143 1144 static inline void set_io_start_time_ns(struct request *req) 1145 { 1146 preempt_disable(); 1147 req->io_start_time_ns = sched_clock(); 1148 preempt_enable(); 1149 } 1150 1151 static inline uint64_t rq_start_time_ns(struct request *req) 1152 { 1153 return req->start_time_ns; 1154 } 1155 1156 static inline uint64_t rq_io_start_time_ns(struct request *req) 1157 { 1158 return req->io_start_time_ns; 1159 } 1160 #else 1161 static inline void set_start_time_ns(struct request *req) {} 1162 static inline void set_io_start_time_ns(struct request *req) {} 1163 static inline uint64_t rq_start_time_ns(struct request *req) 1164 { 1165 return 0; 1166 } 1167 static inline uint64_t rq_io_start_time_ns(struct request *req) 1168 { 1169 return 0; 1170 } 1171 #endif 1172 1173 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1174 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1175 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1176 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1177 1178 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1179 1180 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */ 1181 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */ 1182 1183 struct blk_integrity_exchg { 1184 void *prot_buf; 1185 void *data_buf; 1186 sector_t sector; 1187 unsigned int data_size; 1188 unsigned short sector_size; 1189 const char *disk_name; 1190 }; 1191 1192 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *); 1193 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *); 1194 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int); 1195 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int); 1196 1197 struct blk_integrity { 1198 integrity_gen_fn *generate_fn; 1199 integrity_vrfy_fn *verify_fn; 1200 integrity_set_tag_fn *set_tag_fn; 1201 integrity_get_tag_fn *get_tag_fn; 1202 1203 unsigned short flags; 1204 unsigned short tuple_size; 1205 unsigned short sector_size; 1206 unsigned short tag_size; 1207 1208 const char *name; 1209 1210 struct kobject kobj; 1211 }; 1212 1213 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); 1214 extern void blk_integrity_unregister(struct gendisk *); 1215 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1216 extern int blk_rq_map_integrity_sg(struct request *, struct scatterlist *); 1217 extern int blk_rq_count_integrity_sg(struct request *); 1218 1219 static inline 1220 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1221 { 1222 return bdev->bd_disk->integrity; 1223 } 1224 1225 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1226 { 1227 return disk->integrity; 1228 } 1229 1230 static inline int blk_integrity_rq(struct request *rq) 1231 { 1232 if (rq->bio == NULL) 1233 return 0; 1234 1235 return bio_integrity(rq->bio); 1236 } 1237 1238 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1239 1240 #define blk_integrity_rq(rq) (0) 1241 #define blk_rq_count_integrity_sg(a) (0) 1242 #define blk_rq_map_integrity_sg(a, b) (0) 1243 #define bdev_get_integrity(a) (0) 1244 #define blk_get_integrity(a) (0) 1245 #define blk_integrity_compare(a, b) (0) 1246 #define blk_integrity_register(a, b) (0) 1247 #define blk_integrity_unregister(a) do { } while (0); 1248 1249 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1250 1251 struct block_device_operations { 1252 int (*open) (struct block_device *, fmode_t); 1253 int (*release) (struct gendisk *, fmode_t); 1254 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1255 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1256 int (*direct_access) (struct block_device *, sector_t, 1257 void **, unsigned long *); 1258 int (*media_changed) (struct gendisk *); 1259 void (*unlock_native_capacity) (struct gendisk *); 1260 int (*revalidate_disk) (struct gendisk *); 1261 int (*getgeo)(struct block_device *, struct hd_geometry *); 1262 /* this callback is with swap_lock and sometimes page table lock held */ 1263 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1264 struct module *owner; 1265 }; 1266 1267 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1268 unsigned long); 1269 #else /* CONFIG_BLOCK */ 1270 /* 1271 * stubs for when the block layer is configured out 1272 */ 1273 #define buffer_heads_over_limit 0 1274 1275 static inline long nr_blockdev_pages(void) 1276 { 1277 return 0; 1278 } 1279 1280 #endif /* CONFIG_BLOCK */ 1281 1282 #endif 1283