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 REQ_TYPE_LINUX_BLOCK, /* generic block layer message */ 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 /* 74 * For request of type REQ_TYPE_LINUX_BLOCK, rq->cmd[0] is the opcode being 75 * sent down (similar to how REQ_TYPE_BLOCK_PC means that ->cmd[] holds a 76 * SCSI cdb. 77 * 78 * 0x00 -> 0x3f are driver private, to be used for whatever purpose they need, 79 * typically to differentiate REQ_TYPE_SPECIAL requests. 80 * 81 */ 82 enum { 83 REQ_LB_OP_EJECT = 0x40, /* eject request */ 84 REQ_LB_OP_FLUSH = 0x41, /* flush request */ 85 }; 86 87 /* 88 * request type modified bits. first four bits match BIO_RW* bits, important 89 */ 90 enum rq_flag_bits { 91 __REQ_RW, /* not set, read. set, write */ 92 __REQ_FAILFAST_DEV, /* no driver retries of device errors */ 93 __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ 94 __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ 95 /* above flags must match BIO_RW_* */ 96 __REQ_DISCARD, /* request to discard sectors */ 97 __REQ_SORTED, /* elevator knows about this request */ 98 __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ 99 __REQ_HARDBARRIER, /* may not be passed by drive either */ 100 __REQ_FUA, /* forced unit access */ 101 __REQ_NOMERGE, /* don't touch this for merging */ 102 __REQ_STARTED, /* drive already may have started this one */ 103 __REQ_DONTPREP, /* don't call prep for this one */ 104 __REQ_QUEUED, /* uses queueing */ 105 __REQ_ELVPRIV, /* elevator private data attached */ 106 __REQ_FAILED, /* set if the request failed */ 107 __REQ_QUIET, /* don't worry about errors */ 108 __REQ_PREEMPT, /* set for "ide_preempt" requests */ 109 __REQ_ORDERED_COLOR, /* is before or after barrier */ 110 __REQ_RW_SYNC, /* request is sync (sync write or read) */ 111 __REQ_ALLOCED, /* request came from our alloc pool */ 112 __REQ_RW_META, /* metadata io request */ 113 __REQ_COPY_USER, /* contains copies of user pages */ 114 __REQ_INTEGRITY, /* integrity metadata has been remapped */ 115 __REQ_NOIDLE, /* Don't anticipate more IO after this one */ 116 __REQ_IO_STAT, /* account I/O stat */ 117 __REQ_MIXED_MERGE, /* merge of different types, fail separately */ 118 __REQ_NR_BITS, /* stops here */ 119 }; 120 121 #define REQ_RW (1 << __REQ_RW) 122 #define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV) 123 #define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT) 124 #define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER) 125 #define REQ_DISCARD (1 << __REQ_DISCARD) 126 #define REQ_SORTED (1 << __REQ_SORTED) 127 #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) 128 #define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER) 129 #define REQ_FUA (1 << __REQ_FUA) 130 #define REQ_NOMERGE (1 << __REQ_NOMERGE) 131 #define REQ_STARTED (1 << __REQ_STARTED) 132 #define REQ_DONTPREP (1 << __REQ_DONTPREP) 133 #define REQ_QUEUED (1 << __REQ_QUEUED) 134 #define REQ_ELVPRIV (1 << __REQ_ELVPRIV) 135 #define REQ_FAILED (1 << __REQ_FAILED) 136 #define REQ_QUIET (1 << __REQ_QUIET) 137 #define REQ_PREEMPT (1 << __REQ_PREEMPT) 138 #define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR) 139 #define REQ_RW_SYNC (1 << __REQ_RW_SYNC) 140 #define REQ_ALLOCED (1 << __REQ_ALLOCED) 141 #define REQ_RW_META (1 << __REQ_RW_META) 142 #define REQ_COPY_USER (1 << __REQ_COPY_USER) 143 #define REQ_INTEGRITY (1 << __REQ_INTEGRITY) 144 #define REQ_NOIDLE (1 << __REQ_NOIDLE) 145 #define REQ_IO_STAT (1 << __REQ_IO_STAT) 146 #define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE) 147 148 #define REQ_FAILFAST_MASK (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | \ 149 REQ_FAILFAST_DRIVER) 150 151 #define BLK_MAX_CDB 16 152 153 /* 154 * try to put the fields that are referenced together in the same cacheline. 155 * if you modify this structure, be sure to check block/blk-core.c:rq_init() 156 * as well! 157 */ 158 struct request { 159 struct list_head queuelist; 160 struct call_single_data csd; 161 int cpu; 162 163 struct request_queue *q; 164 165 unsigned int cmd_flags; 166 enum rq_cmd_type_bits cmd_type; 167 unsigned long atomic_flags; 168 169 /* the following two fields are internal, NEVER access directly */ 170 sector_t __sector; /* sector cursor */ 171 unsigned int __data_len; /* total data len */ 172 173 struct bio *bio; 174 struct bio *biotail; 175 176 struct hlist_node hash; /* merge hash */ 177 /* 178 * The rb_node is only used inside the io scheduler, requests 179 * are pruned when moved to the dispatch queue. So let the 180 * completion_data share space with the rb_node. 181 */ 182 union { 183 struct rb_node rb_node; /* sort/lookup */ 184 void *completion_data; 185 }; 186 187 /* 188 * two pointers are available for the IO schedulers, if they need 189 * more they have to dynamically allocate it. 190 */ 191 void *elevator_private; 192 void *elevator_private2; 193 194 struct gendisk *rq_disk; 195 unsigned long start_time; 196 197 /* Number of scatter-gather DMA addr+len pairs after 198 * physical address coalescing is performed. 199 */ 200 unsigned short nr_phys_segments; 201 202 unsigned short ioprio; 203 204 void *special; /* opaque pointer available for LLD use */ 205 char *buffer; /* kaddr of the current segment if available */ 206 207 int tag; 208 int errors; 209 210 int ref_count; 211 212 /* 213 * when request is used as a packet command carrier 214 */ 215 unsigned short cmd_len; 216 unsigned char __cmd[BLK_MAX_CDB]; 217 unsigned char *cmd; 218 219 unsigned int extra_len; /* length of alignment and padding */ 220 unsigned int sense_len; 221 unsigned int resid_len; /* residual count */ 222 void *sense; 223 224 unsigned long deadline; 225 struct list_head timeout_list; 226 unsigned int timeout; 227 int retries; 228 229 /* 230 * completion callback. 231 */ 232 rq_end_io_fn *end_io; 233 void *end_io_data; 234 235 /* for bidi */ 236 struct request *next_rq; 237 }; 238 239 static inline unsigned short req_get_ioprio(struct request *req) 240 { 241 return req->ioprio; 242 } 243 244 /* 245 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME 246 * requests. Some step values could eventually be made generic. 247 */ 248 struct request_pm_state 249 { 250 /* PM state machine step value, currently driver specific */ 251 int pm_step; 252 /* requested PM state value (S1, S2, S3, S4, ...) */ 253 u32 pm_state; 254 void* data; /* for driver use */ 255 }; 256 257 #include <linux/elevator.h> 258 259 typedef void (request_fn_proc) (struct request_queue *q); 260 typedef int (make_request_fn) (struct request_queue *q, struct bio *bio); 261 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 262 typedef void (unplug_fn) (struct request_queue *); 263 264 struct bio_vec; 265 struct bvec_merge_data { 266 struct block_device *bi_bdev; 267 sector_t bi_sector; 268 unsigned bi_size; 269 unsigned long bi_rw; 270 }; 271 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *, 272 struct bio_vec *); 273 typedef void (prepare_flush_fn) (struct request_queue *, struct request *); 274 typedef void (softirq_done_fn)(struct request *); 275 typedef int (dma_drain_needed_fn)(struct request *); 276 typedef int (lld_busy_fn) (struct request_queue *q); 277 278 enum blk_eh_timer_return { 279 BLK_EH_NOT_HANDLED, 280 BLK_EH_HANDLED, 281 BLK_EH_RESET_TIMER, 282 }; 283 284 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 285 286 enum blk_queue_state { 287 Queue_down, 288 Queue_up, 289 }; 290 291 struct blk_queue_tag { 292 struct request **tag_index; /* map of busy tags */ 293 unsigned long *tag_map; /* bit map of free/busy tags */ 294 int busy; /* current depth */ 295 int max_depth; /* what we will send to device */ 296 int real_max_depth; /* what the array can hold */ 297 atomic_t refcnt; /* map can be shared */ 298 }; 299 300 #define BLK_SCSI_MAX_CMDS (256) 301 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 302 303 struct queue_limits { 304 unsigned long bounce_pfn; 305 unsigned long seg_boundary_mask; 306 307 unsigned int max_hw_sectors; 308 unsigned int max_sectors; 309 unsigned int max_segment_size; 310 unsigned int physical_block_size; 311 unsigned int alignment_offset; 312 unsigned int io_min; 313 unsigned int io_opt; 314 unsigned int max_discard_sectors; 315 unsigned int discard_granularity; 316 unsigned int discard_alignment; 317 318 unsigned short logical_block_size; 319 unsigned short max_hw_segments; 320 unsigned short max_phys_segments; 321 322 unsigned char misaligned; 323 unsigned char discard_misaligned; 324 unsigned char no_cluster; 325 signed char discard_zeroes_data; 326 }; 327 328 struct request_queue 329 { 330 /* 331 * Together with queue_head for cacheline sharing 332 */ 333 struct list_head queue_head; 334 struct request *last_merge; 335 struct elevator_queue *elevator; 336 337 /* 338 * the queue request freelist, one for reads and one for writes 339 */ 340 struct request_list rq; 341 342 request_fn_proc *request_fn; 343 make_request_fn *make_request_fn; 344 prep_rq_fn *prep_rq_fn; 345 unplug_fn *unplug_fn; 346 merge_bvec_fn *merge_bvec_fn; 347 prepare_flush_fn *prepare_flush_fn; 348 softirq_done_fn *softirq_done_fn; 349 rq_timed_out_fn *rq_timed_out_fn; 350 dma_drain_needed_fn *dma_drain_needed; 351 lld_busy_fn *lld_busy_fn; 352 353 /* 354 * Dispatch queue sorting 355 */ 356 sector_t end_sector; 357 struct request *boundary_rq; 358 359 /* 360 * Auto-unplugging state 361 */ 362 struct timer_list unplug_timer; 363 int unplug_thresh; /* After this many requests */ 364 unsigned long unplug_delay; /* After this many jiffies */ 365 struct work_struct unplug_work; 366 367 struct backing_dev_info backing_dev_info; 368 369 /* 370 * The queue owner gets to use this for whatever they like. 371 * ll_rw_blk doesn't touch it. 372 */ 373 void *queuedata; 374 375 /* 376 * queue needs bounce pages for pages above this limit 377 */ 378 gfp_t bounce_gfp; 379 380 /* 381 * various queue flags, see QUEUE_* below 382 */ 383 unsigned long queue_flags; 384 385 /* 386 * protects queue structures from reentrancy. ->__queue_lock should 387 * _never_ be used directly, it is queue private. always use 388 * ->queue_lock. 389 */ 390 spinlock_t __queue_lock; 391 spinlock_t *queue_lock; 392 393 /* 394 * queue kobject 395 */ 396 struct kobject kobj; 397 398 /* 399 * queue settings 400 */ 401 unsigned long nr_requests; /* Max # of requests */ 402 unsigned int nr_congestion_on; 403 unsigned int nr_congestion_off; 404 unsigned int nr_batching; 405 406 void *dma_drain_buffer; 407 unsigned int dma_drain_size; 408 unsigned int dma_pad_mask; 409 unsigned int dma_alignment; 410 411 struct blk_queue_tag *queue_tags; 412 struct list_head tag_busy_list; 413 414 unsigned int nr_sorted; 415 unsigned int in_flight[2]; 416 417 unsigned int rq_timeout; 418 struct timer_list timeout; 419 struct list_head timeout_list; 420 421 struct queue_limits limits; 422 423 /* 424 * sg stuff 425 */ 426 unsigned int sg_timeout; 427 unsigned int sg_reserved_size; 428 int node; 429 #ifdef CONFIG_BLK_DEV_IO_TRACE 430 struct blk_trace *blk_trace; 431 #endif 432 /* 433 * reserved for flush operations 434 */ 435 unsigned int ordered, next_ordered, ordseq; 436 int orderr, ordcolor; 437 struct request pre_flush_rq, bar_rq, post_flush_rq; 438 struct request *orig_bar_rq; 439 440 struct mutex sysfs_lock; 441 442 #if defined(CONFIG_BLK_DEV_BSG) 443 struct bsg_class_device bsg_dev; 444 #endif 445 }; 446 447 #define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */ 448 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 449 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 450 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 451 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 452 #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ 453 #define QUEUE_FLAG_REENTER 6 /* Re-entrancy avoidance */ 454 #define QUEUE_FLAG_PLUGGED 7 /* queue is plugged */ 455 #define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */ 456 #define QUEUE_FLAG_BIDI 9 /* queue supports bidi requests */ 457 #define QUEUE_FLAG_NOMERGES 10 /* disable merge attempts */ 458 #define QUEUE_FLAG_SAME_COMP 11 /* force complete on same CPU */ 459 #define QUEUE_FLAG_FAIL_IO 12 /* fake timeout */ 460 #define QUEUE_FLAG_STACKABLE 13 /* supports request stacking */ 461 #define QUEUE_FLAG_NONROT 14 /* non-rotational device (SSD) */ 462 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 463 #define QUEUE_FLAG_IO_STAT 15 /* do IO stats */ 464 #define QUEUE_FLAG_CQ 16 /* hardware does queuing */ 465 #define QUEUE_FLAG_DISCARD 17 /* supports DISCARD */ 466 467 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 468 (1 << QUEUE_FLAG_CLUSTER) | \ 469 (1 << QUEUE_FLAG_STACKABLE) | \ 470 (1 << QUEUE_FLAG_SAME_COMP)) 471 472 static inline int queue_is_locked(struct request_queue *q) 473 { 474 #ifdef CONFIG_SMP 475 spinlock_t *lock = q->queue_lock; 476 return lock && spin_is_locked(lock); 477 #else 478 return 1; 479 #endif 480 } 481 482 static inline void queue_flag_set_unlocked(unsigned int flag, 483 struct request_queue *q) 484 { 485 __set_bit(flag, &q->queue_flags); 486 } 487 488 static inline int queue_flag_test_and_clear(unsigned int flag, 489 struct request_queue *q) 490 { 491 WARN_ON_ONCE(!queue_is_locked(q)); 492 493 if (test_bit(flag, &q->queue_flags)) { 494 __clear_bit(flag, &q->queue_flags); 495 return 1; 496 } 497 498 return 0; 499 } 500 501 static inline int queue_flag_test_and_set(unsigned int flag, 502 struct request_queue *q) 503 { 504 WARN_ON_ONCE(!queue_is_locked(q)); 505 506 if (!test_bit(flag, &q->queue_flags)) { 507 __set_bit(flag, &q->queue_flags); 508 return 0; 509 } 510 511 return 1; 512 } 513 514 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 515 { 516 WARN_ON_ONCE(!queue_is_locked(q)); 517 __set_bit(flag, &q->queue_flags); 518 } 519 520 static inline void queue_flag_clear_unlocked(unsigned int flag, 521 struct request_queue *q) 522 { 523 __clear_bit(flag, &q->queue_flags); 524 } 525 526 static inline int queue_in_flight(struct request_queue *q) 527 { 528 return q->in_flight[0] + q->in_flight[1]; 529 } 530 531 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 532 { 533 WARN_ON_ONCE(!queue_is_locked(q)); 534 __clear_bit(flag, &q->queue_flags); 535 } 536 537 enum { 538 /* 539 * Hardbarrier is supported with one of the following methods. 540 * 541 * NONE : hardbarrier unsupported 542 * DRAIN : ordering by draining is enough 543 * DRAIN_FLUSH : ordering by draining w/ pre and post flushes 544 * DRAIN_FUA : ordering by draining w/ pre flush and FUA write 545 * TAG : ordering by tag is enough 546 * TAG_FLUSH : ordering by tag w/ pre and post flushes 547 * TAG_FUA : ordering by tag w/ pre flush and FUA write 548 */ 549 QUEUE_ORDERED_BY_DRAIN = 0x01, 550 QUEUE_ORDERED_BY_TAG = 0x02, 551 QUEUE_ORDERED_DO_PREFLUSH = 0x10, 552 QUEUE_ORDERED_DO_BAR = 0x20, 553 QUEUE_ORDERED_DO_POSTFLUSH = 0x40, 554 QUEUE_ORDERED_DO_FUA = 0x80, 555 556 QUEUE_ORDERED_NONE = 0x00, 557 558 QUEUE_ORDERED_DRAIN = QUEUE_ORDERED_BY_DRAIN | 559 QUEUE_ORDERED_DO_BAR, 560 QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN | 561 QUEUE_ORDERED_DO_PREFLUSH | 562 QUEUE_ORDERED_DO_POSTFLUSH, 563 QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN | 564 QUEUE_ORDERED_DO_PREFLUSH | 565 QUEUE_ORDERED_DO_FUA, 566 567 QUEUE_ORDERED_TAG = QUEUE_ORDERED_BY_TAG | 568 QUEUE_ORDERED_DO_BAR, 569 QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG | 570 QUEUE_ORDERED_DO_PREFLUSH | 571 QUEUE_ORDERED_DO_POSTFLUSH, 572 QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG | 573 QUEUE_ORDERED_DO_PREFLUSH | 574 QUEUE_ORDERED_DO_FUA, 575 576 /* 577 * Ordered operation sequence 578 */ 579 QUEUE_ORDSEQ_STARTED = 0x01, /* flushing in progress */ 580 QUEUE_ORDSEQ_DRAIN = 0x02, /* waiting for the queue to be drained */ 581 QUEUE_ORDSEQ_PREFLUSH = 0x04, /* pre-flushing in progress */ 582 QUEUE_ORDSEQ_BAR = 0x08, /* original barrier req in progress */ 583 QUEUE_ORDSEQ_POSTFLUSH = 0x10, /* post-flushing in progress */ 584 QUEUE_ORDSEQ_DONE = 0x20, 585 }; 586 587 #define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags) 588 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 589 #define blk_queue_queuing(q) test_bit(QUEUE_FLAG_CQ, &(q)->queue_flags) 590 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 591 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 592 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 593 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 594 #define blk_queue_flushing(q) ((q)->ordseq) 595 #define blk_queue_stackable(q) \ 596 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 597 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 598 599 #define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS) 600 #define blk_pc_request(rq) ((rq)->cmd_type == REQ_TYPE_BLOCK_PC) 601 #define blk_special_request(rq) ((rq)->cmd_type == REQ_TYPE_SPECIAL) 602 #define blk_sense_request(rq) ((rq)->cmd_type == REQ_TYPE_SENSE) 603 604 #define blk_failfast_dev(rq) ((rq)->cmd_flags & REQ_FAILFAST_DEV) 605 #define blk_failfast_transport(rq) ((rq)->cmd_flags & REQ_FAILFAST_TRANSPORT) 606 #define blk_failfast_driver(rq) ((rq)->cmd_flags & REQ_FAILFAST_DRIVER) 607 #define blk_noretry_request(rq) (blk_failfast_dev(rq) || \ 608 blk_failfast_transport(rq) || \ 609 blk_failfast_driver(rq)) 610 #define blk_rq_started(rq) ((rq)->cmd_flags & REQ_STARTED) 611 #define blk_rq_io_stat(rq) ((rq)->cmd_flags & REQ_IO_STAT) 612 #define blk_rq_quiet(rq) ((rq)->cmd_flags & REQ_QUIET) 613 614 #define blk_account_rq(rq) (blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq))) 615 616 #define blk_pm_suspend_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND) 617 #define blk_pm_resume_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_RESUME) 618 #define blk_pm_request(rq) \ 619 (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq)) 620 621 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 622 #define blk_sorted_rq(rq) ((rq)->cmd_flags & REQ_SORTED) 623 #define blk_barrier_rq(rq) ((rq)->cmd_flags & REQ_HARDBARRIER) 624 #define blk_fua_rq(rq) ((rq)->cmd_flags & REQ_FUA) 625 #define blk_discard_rq(rq) ((rq)->cmd_flags & REQ_DISCARD) 626 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 627 /* rq->queuelist of dequeued request must be list_empty() */ 628 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 629 630 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 631 632 #define rq_data_dir(rq) ((rq)->cmd_flags & 1) 633 634 /* 635 * We regard a request as sync, if either a read or a sync write 636 */ 637 static inline bool rw_is_sync(unsigned int rw_flags) 638 { 639 return !(rw_flags & REQ_RW) || (rw_flags & REQ_RW_SYNC); 640 } 641 642 static inline bool rq_is_sync(struct request *rq) 643 { 644 return rw_is_sync(rq->cmd_flags); 645 } 646 647 #define rq_is_meta(rq) ((rq)->cmd_flags & REQ_RW_META) 648 #define rq_noidle(rq) ((rq)->cmd_flags & REQ_NOIDLE) 649 650 static inline int blk_queue_full(struct request_queue *q, int sync) 651 { 652 if (sync) 653 return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags); 654 return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags); 655 } 656 657 static inline void blk_set_queue_full(struct request_queue *q, int sync) 658 { 659 if (sync) 660 queue_flag_set(QUEUE_FLAG_SYNCFULL, q); 661 else 662 queue_flag_set(QUEUE_FLAG_ASYNCFULL, q); 663 } 664 665 static inline void blk_clear_queue_full(struct request_queue *q, int sync) 666 { 667 if (sync) 668 queue_flag_clear(QUEUE_FLAG_SYNCFULL, q); 669 else 670 queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q); 671 } 672 673 674 /* 675 * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may 676 * it already be started by driver. 677 */ 678 #define RQ_NOMERGE_FLAGS \ 679 (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER) 680 #define rq_mergeable(rq) \ 681 (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \ 682 (blk_discard_rq(rq) || blk_fs_request((rq)))) 683 684 /* 685 * q->prep_rq_fn return values 686 */ 687 #define BLKPREP_OK 0 /* serve it */ 688 #define BLKPREP_KILL 1 /* fatal error, kill */ 689 #define BLKPREP_DEFER 2 /* leave on queue */ 690 691 extern unsigned long blk_max_low_pfn, blk_max_pfn; 692 693 /* 694 * standard bounce addresses: 695 * 696 * BLK_BOUNCE_HIGH : bounce all highmem pages 697 * BLK_BOUNCE_ANY : don't bounce anything 698 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 699 */ 700 701 #if BITS_PER_LONG == 32 702 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 703 #else 704 #define BLK_BOUNCE_HIGH -1ULL 705 #endif 706 #define BLK_BOUNCE_ANY (-1ULL) 707 #define BLK_BOUNCE_ISA (ISA_DMA_THRESHOLD) 708 709 /* 710 * default timeout for SG_IO if none specified 711 */ 712 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 713 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 714 715 #ifdef CONFIG_BOUNCE 716 extern int init_emergency_isa_pool(void); 717 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 718 #else 719 static inline int init_emergency_isa_pool(void) 720 { 721 return 0; 722 } 723 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 724 { 725 } 726 #endif /* CONFIG_MMU */ 727 728 struct rq_map_data { 729 struct page **pages; 730 int page_order; 731 int nr_entries; 732 unsigned long offset; 733 int null_mapped; 734 int from_user; 735 }; 736 737 struct req_iterator { 738 int i; 739 struct bio *bio; 740 }; 741 742 /* This should not be used directly - use rq_for_each_segment */ 743 #define for_each_bio(_bio) \ 744 for (; _bio; _bio = _bio->bi_next) 745 #define __rq_for_each_bio(_bio, rq) \ 746 if ((rq->bio)) \ 747 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 748 749 #define rq_for_each_segment(bvl, _rq, _iter) \ 750 __rq_for_each_bio(_iter.bio, _rq) \ 751 bio_for_each_segment(bvl, _iter.bio, _iter.i) 752 753 #define rq_iter_last(rq, _iter) \ 754 (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1) 755 756 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 757 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 758 #endif 759 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 760 extern void rq_flush_dcache_pages(struct request *rq); 761 #else 762 static inline void rq_flush_dcache_pages(struct request *rq) 763 { 764 } 765 #endif 766 767 extern int blk_register_queue(struct gendisk *disk); 768 extern void blk_unregister_queue(struct gendisk *disk); 769 extern void register_disk(struct gendisk *dev); 770 extern void generic_make_request(struct bio *bio); 771 extern void blk_rq_init(struct request_queue *q, struct request *rq); 772 extern void blk_put_request(struct request *); 773 extern void __blk_put_request(struct request_queue *, struct request *); 774 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 775 extern struct request *blk_make_request(struct request_queue *, struct bio *, 776 gfp_t); 777 extern void blk_insert_request(struct request_queue *, struct request *, int, void *); 778 extern void blk_requeue_request(struct request_queue *, struct request *); 779 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); 780 extern int blk_lld_busy(struct request_queue *q); 781 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 782 struct bio_set *bs, gfp_t gfp_mask, 783 int (*bio_ctr)(struct bio *, struct bio *, void *), 784 void *data); 785 extern void blk_rq_unprep_clone(struct request *rq); 786 extern int blk_insert_cloned_request(struct request_queue *q, 787 struct request *rq); 788 extern void blk_plug_device(struct request_queue *); 789 extern void blk_plug_device_unlocked(struct request_queue *); 790 extern int blk_remove_plug(struct request_queue *); 791 extern void blk_recount_segments(struct request_queue *, struct bio *); 792 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 793 unsigned int, void __user *); 794 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 795 struct scsi_ioctl_command __user *); 796 797 /* 798 * A queue has just exitted congestion. Note this in the global counter of 799 * congested queues, and wake up anyone who was waiting for requests to be 800 * put back. 801 */ 802 static inline void blk_clear_queue_congested(struct request_queue *q, int sync) 803 { 804 clear_bdi_congested(&q->backing_dev_info, sync); 805 } 806 807 /* 808 * A queue has just entered congestion. Flag that in the queue's VM-visible 809 * state flags and increment the global gounter of congested queues. 810 */ 811 static inline void blk_set_queue_congested(struct request_queue *q, int sync) 812 { 813 set_bdi_congested(&q->backing_dev_info, sync); 814 } 815 816 extern void blk_start_queue(struct request_queue *q); 817 extern void blk_stop_queue(struct request_queue *q); 818 extern void blk_sync_queue(struct request_queue *q); 819 extern void __blk_stop_queue(struct request_queue *q); 820 extern void __blk_run_queue(struct request_queue *); 821 extern void blk_run_queue(struct request_queue *); 822 extern int blk_rq_map_user(struct request_queue *, struct request *, 823 struct rq_map_data *, void __user *, unsigned long, 824 gfp_t); 825 extern int blk_rq_unmap_user(struct bio *); 826 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 827 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 828 struct rq_map_data *, struct sg_iovec *, int, 829 unsigned int, gfp_t); 830 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 831 struct request *, int); 832 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 833 struct request *, int, rq_end_io_fn *); 834 extern void blk_unplug(struct request_queue *q); 835 836 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 837 { 838 return bdev->bd_disk->queue; 839 } 840 841 /* 842 * blk_rq_pos() : the current sector 843 * blk_rq_bytes() : bytes left in the entire request 844 * blk_rq_cur_bytes() : bytes left in the current segment 845 * blk_rq_err_bytes() : bytes left till the next error boundary 846 * blk_rq_sectors() : sectors left in the entire request 847 * blk_rq_cur_sectors() : sectors left in the current segment 848 * blk_rq_err_sectors() : sectors left till the next error boundary 849 */ 850 static inline sector_t blk_rq_pos(const struct request *rq) 851 { 852 return rq->__sector; 853 } 854 855 static inline unsigned int blk_rq_bytes(const struct request *rq) 856 { 857 return rq->__data_len; 858 } 859 860 static inline int blk_rq_cur_bytes(const struct request *rq) 861 { 862 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 863 } 864 865 extern unsigned int blk_rq_err_bytes(const struct request *rq); 866 867 static inline unsigned int blk_rq_sectors(const struct request *rq) 868 { 869 return blk_rq_bytes(rq) >> 9; 870 } 871 872 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 873 { 874 return blk_rq_cur_bytes(rq) >> 9; 875 } 876 877 static inline unsigned int blk_rq_err_sectors(const struct request *rq) 878 { 879 return blk_rq_err_bytes(rq) >> 9; 880 } 881 882 /* 883 * Request issue related functions. 884 */ 885 extern struct request *blk_peek_request(struct request_queue *q); 886 extern void blk_start_request(struct request *rq); 887 extern struct request *blk_fetch_request(struct request_queue *q); 888 889 /* 890 * Request completion related functions. 891 * 892 * blk_update_request() completes given number of bytes and updates 893 * the request without completing it. 894 * 895 * blk_end_request() and friends. __blk_end_request() must be called 896 * with the request queue spinlock acquired. 897 * 898 * Several drivers define their own end_request and call 899 * blk_end_request() for parts of the original function. 900 * This prevents code duplication in drivers. 901 */ 902 extern bool blk_update_request(struct request *rq, int error, 903 unsigned int nr_bytes); 904 extern bool blk_end_request(struct request *rq, int error, 905 unsigned int nr_bytes); 906 extern void blk_end_request_all(struct request *rq, int error); 907 extern bool blk_end_request_cur(struct request *rq, int error); 908 extern bool blk_end_request_err(struct request *rq, int error); 909 extern bool __blk_end_request(struct request *rq, int error, 910 unsigned int nr_bytes); 911 extern void __blk_end_request_all(struct request *rq, int error); 912 extern bool __blk_end_request_cur(struct request *rq, int error); 913 extern bool __blk_end_request_err(struct request *rq, int error); 914 915 extern void blk_complete_request(struct request *); 916 extern void __blk_complete_request(struct request *); 917 extern void blk_abort_request(struct request *); 918 extern void blk_abort_queue(struct request_queue *); 919 920 /* 921 * Access functions for manipulating queue properties 922 */ 923 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 924 spinlock_t *lock, int node_id); 925 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 926 extern void blk_cleanup_queue(struct request_queue *); 927 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 928 extern void blk_queue_bounce_limit(struct request_queue *, u64); 929 extern void blk_queue_max_sectors(struct request_queue *, unsigned int); 930 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 931 extern void blk_queue_max_phys_segments(struct request_queue *, unsigned short); 932 extern void blk_queue_max_hw_segments(struct request_queue *, unsigned short); 933 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 934 extern void blk_queue_max_discard_sectors(struct request_queue *q, 935 unsigned int max_discard_sectors); 936 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 937 extern void blk_queue_physical_block_size(struct request_queue *, unsigned short); 938 extern void blk_queue_alignment_offset(struct request_queue *q, 939 unsigned int alignment); 940 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 941 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 942 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 943 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 944 extern void blk_set_default_limits(struct queue_limits *lim); 945 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 946 sector_t offset); 947 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 948 sector_t offset); 949 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 950 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 951 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 952 extern int blk_queue_dma_drain(struct request_queue *q, 953 dma_drain_needed_fn *dma_drain_needed, 954 void *buf, unsigned int size); 955 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 956 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 957 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 958 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); 959 extern void blk_queue_dma_alignment(struct request_queue *, int); 960 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 961 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 962 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 963 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 964 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 965 extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *); 966 extern bool blk_do_ordered(struct request_queue *, struct request **); 967 extern unsigned blk_ordered_cur_seq(struct request_queue *); 968 extern unsigned blk_ordered_req_seq(struct request *); 969 extern bool blk_ordered_complete_seq(struct request_queue *, unsigned, int); 970 971 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 972 extern void blk_dump_rq_flags(struct request *, char *); 973 extern void generic_unplug_device(struct request_queue *); 974 extern long nr_blockdev_pages(void); 975 976 int blk_get_queue(struct request_queue *); 977 struct request_queue *blk_alloc_queue(gfp_t); 978 struct request_queue *blk_alloc_queue_node(gfp_t, int); 979 extern void blk_put_queue(struct request_queue *); 980 981 /* 982 * tag stuff 983 */ 984 #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED) 985 extern int blk_queue_start_tag(struct request_queue *, struct request *); 986 extern struct request *blk_queue_find_tag(struct request_queue *, int); 987 extern void blk_queue_end_tag(struct request_queue *, struct request *); 988 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *); 989 extern void blk_queue_free_tags(struct request_queue *); 990 extern int blk_queue_resize_tags(struct request_queue *, int); 991 extern void blk_queue_invalidate_tags(struct request_queue *); 992 extern struct blk_queue_tag *blk_init_tags(int); 993 extern void blk_free_tags(struct blk_queue_tag *); 994 995 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 996 int tag) 997 { 998 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 999 return NULL; 1000 return bqt->tag_index[tag]; 1001 } 1002 1003 extern int blkdev_issue_flush(struct block_device *, sector_t *); 1004 #define DISCARD_FL_WAIT 0x01 /* wait for completion */ 1005 #define DISCARD_FL_BARRIER 0x02 /* issue DISCARD_BARRIER request */ 1006 extern int blkdev_issue_discard(struct block_device *, sector_t sector, 1007 sector_t nr_sects, gfp_t, int flags); 1008 1009 static inline int sb_issue_discard(struct super_block *sb, 1010 sector_t block, sector_t nr_blocks) 1011 { 1012 block <<= (sb->s_blocksize_bits - 9); 1013 nr_blocks <<= (sb->s_blocksize_bits - 9); 1014 return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_KERNEL, 1015 DISCARD_FL_BARRIER); 1016 } 1017 1018 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 1019 1020 #define MAX_PHYS_SEGMENTS 128 1021 #define MAX_HW_SEGMENTS 128 1022 #define SAFE_MAX_SECTORS 255 1023 #define BLK_DEF_MAX_SECTORS 1024 1024 1025 #define MAX_SEGMENT_SIZE 65536 1026 1027 #define BLK_SEG_BOUNDARY_MASK 0xFFFFFFFFUL 1028 1029 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1030 1031 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 1032 { 1033 return q->limits.bounce_pfn; 1034 } 1035 1036 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1037 { 1038 return q->limits.seg_boundary_mask; 1039 } 1040 1041 static inline unsigned int queue_max_sectors(struct request_queue *q) 1042 { 1043 return q->limits.max_sectors; 1044 } 1045 1046 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1047 { 1048 return q->limits.max_hw_sectors; 1049 } 1050 1051 static inline unsigned short queue_max_hw_segments(struct request_queue *q) 1052 { 1053 return q->limits.max_hw_segments; 1054 } 1055 1056 static inline unsigned short queue_max_phys_segments(struct request_queue *q) 1057 { 1058 return q->limits.max_phys_segments; 1059 } 1060 1061 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1062 { 1063 return q->limits.max_segment_size; 1064 } 1065 1066 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1067 { 1068 int retval = 512; 1069 1070 if (q && q->limits.logical_block_size) 1071 retval = q->limits.logical_block_size; 1072 1073 return retval; 1074 } 1075 1076 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1077 { 1078 return queue_logical_block_size(bdev_get_queue(bdev)); 1079 } 1080 1081 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1082 { 1083 return q->limits.physical_block_size; 1084 } 1085 1086 static inline int bdev_physical_block_size(struct block_device *bdev) 1087 { 1088 return queue_physical_block_size(bdev_get_queue(bdev)); 1089 } 1090 1091 static inline unsigned int queue_io_min(struct request_queue *q) 1092 { 1093 return q->limits.io_min; 1094 } 1095 1096 static inline int bdev_io_min(struct block_device *bdev) 1097 { 1098 return queue_io_min(bdev_get_queue(bdev)); 1099 } 1100 1101 static inline unsigned int queue_io_opt(struct request_queue *q) 1102 { 1103 return q->limits.io_opt; 1104 } 1105 1106 static inline int bdev_io_opt(struct block_device *bdev) 1107 { 1108 return queue_io_opt(bdev_get_queue(bdev)); 1109 } 1110 1111 static inline int queue_alignment_offset(struct request_queue *q) 1112 { 1113 if (q->limits.misaligned) 1114 return -1; 1115 1116 return q->limits.alignment_offset; 1117 } 1118 1119 static inline int queue_sector_alignment_offset(struct request_queue *q, 1120 sector_t sector) 1121 { 1122 return ((sector << 9) - q->limits.alignment_offset) 1123 & (q->limits.io_min - 1); 1124 } 1125 1126 static inline int bdev_alignment_offset(struct block_device *bdev) 1127 { 1128 struct request_queue *q = bdev_get_queue(bdev); 1129 1130 if (q->limits.misaligned) 1131 return -1; 1132 1133 if (bdev != bdev->bd_contains) 1134 return bdev->bd_part->alignment_offset; 1135 1136 return q->limits.alignment_offset; 1137 } 1138 1139 static inline int queue_discard_alignment(struct request_queue *q) 1140 { 1141 if (q->limits.discard_misaligned) 1142 return -1; 1143 1144 return q->limits.discard_alignment; 1145 } 1146 1147 static inline int queue_sector_discard_alignment(struct request_queue *q, 1148 sector_t sector) 1149 { 1150 return ((sector << 9) - q->limits.discard_alignment) 1151 & (q->limits.discard_granularity - 1); 1152 } 1153 1154 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1155 { 1156 if (q->limits.discard_zeroes_data == 1) 1157 return 1; 1158 1159 return 0; 1160 } 1161 1162 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1163 { 1164 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1165 } 1166 1167 static inline int queue_dma_alignment(struct request_queue *q) 1168 { 1169 return q ? q->dma_alignment : 511; 1170 } 1171 1172 static inline int blk_rq_aligned(struct request_queue *q, void *addr, 1173 unsigned int len) 1174 { 1175 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1176 return !((unsigned long)addr & alignment) && !(len & alignment); 1177 } 1178 1179 /* assumes size > 256 */ 1180 static inline unsigned int blksize_bits(unsigned int size) 1181 { 1182 unsigned int bits = 8; 1183 do { 1184 bits++; 1185 size >>= 1; 1186 } while (size > 256); 1187 return bits; 1188 } 1189 1190 static inline unsigned int block_size(struct block_device *bdev) 1191 { 1192 return bdev->bd_block_size; 1193 } 1194 1195 typedef struct {struct page *v;} Sector; 1196 1197 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1198 1199 static inline void put_dev_sector(Sector p) 1200 { 1201 page_cache_release(p.v); 1202 } 1203 1204 struct work_struct; 1205 int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); 1206 1207 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1208 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1209 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1210 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1211 1212 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1213 1214 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */ 1215 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */ 1216 1217 struct blk_integrity_exchg { 1218 void *prot_buf; 1219 void *data_buf; 1220 sector_t sector; 1221 unsigned int data_size; 1222 unsigned short sector_size; 1223 const char *disk_name; 1224 }; 1225 1226 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *); 1227 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *); 1228 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int); 1229 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int); 1230 1231 struct blk_integrity { 1232 integrity_gen_fn *generate_fn; 1233 integrity_vrfy_fn *verify_fn; 1234 integrity_set_tag_fn *set_tag_fn; 1235 integrity_get_tag_fn *get_tag_fn; 1236 1237 unsigned short flags; 1238 unsigned short tuple_size; 1239 unsigned short sector_size; 1240 unsigned short tag_size; 1241 1242 const char *name; 1243 1244 struct kobject kobj; 1245 }; 1246 1247 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); 1248 extern void blk_integrity_unregister(struct gendisk *); 1249 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1250 extern int blk_rq_map_integrity_sg(struct request *, struct scatterlist *); 1251 extern int blk_rq_count_integrity_sg(struct request *); 1252 1253 static inline 1254 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1255 { 1256 return bdev->bd_disk->integrity; 1257 } 1258 1259 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1260 { 1261 return disk->integrity; 1262 } 1263 1264 static inline int blk_integrity_rq(struct request *rq) 1265 { 1266 if (rq->bio == NULL) 1267 return 0; 1268 1269 return bio_integrity(rq->bio); 1270 } 1271 1272 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1273 1274 #define blk_integrity_rq(rq) (0) 1275 #define blk_rq_count_integrity_sg(a) (0) 1276 #define blk_rq_map_integrity_sg(a, b) (0) 1277 #define bdev_get_integrity(a) (0) 1278 #define blk_get_integrity(a) (0) 1279 #define blk_integrity_compare(a, b) (0) 1280 #define blk_integrity_register(a, b) (0) 1281 #define blk_integrity_unregister(a) do { } while (0); 1282 1283 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1284 1285 struct block_device_operations { 1286 int (*open) (struct block_device *, fmode_t); 1287 int (*release) (struct gendisk *, fmode_t); 1288 int (*locked_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1289 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1290 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1291 int (*direct_access) (struct block_device *, sector_t, 1292 void **, unsigned long *); 1293 int (*media_changed) (struct gendisk *); 1294 unsigned long long (*set_capacity) (struct gendisk *, 1295 unsigned long long); 1296 int (*revalidate_disk) (struct gendisk *); 1297 int (*getgeo)(struct block_device *, struct hd_geometry *); 1298 struct module *owner; 1299 }; 1300 1301 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1302 unsigned long); 1303 #else /* CONFIG_BLOCK */ 1304 /* 1305 * stubs for when the block layer is configured out 1306 */ 1307 #define buffer_heads_over_limit 0 1308 1309 static inline long nr_blockdev_pages(void) 1310 { 1311 return 0; 1312 } 1313 1314 #endif /* CONFIG_BLOCK */ 1315 1316 #endif 1317