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; 161 162 struct request_queue *q; 163 164 unsigned int cmd_flags; 165 enum rq_cmd_type_bits cmd_type; 166 unsigned long atomic_flags; 167 168 int cpu; 169 170 /* the following two fields are internal, NEVER access directly */ 171 unsigned int __data_len; /* total data len */ 172 sector_t __sector; /* sector cursor */ 173 174 struct bio *bio; 175 struct bio *biotail; 176 177 struct hlist_node hash; /* merge hash */ 178 /* 179 * The rb_node is only used inside the io scheduler, requests 180 * are pruned when moved to the dispatch queue. So let the 181 * completion_data share space with the rb_node. 182 */ 183 union { 184 struct rb_node rb_node; /* sort/lookup */ 185 void *completion_data; 186 }; 187 188 /* 189 * Three pointers are available for the IO schedulers, if they need 190 * more they have to dynamically allocate it. 191 */ 192 void *elevator_private; 193 void *elevator_private2; 194 void *elevator_private3; 195 196 struct gendisk *rq_disk; 197 unsigned long start_time; 198 #ifdef CONFIG_BLK_CGROUP 199 unsigned long long start_time_ns; 200 unsigned long long io_start_time_ns; /* when passed to hardware */ 201 #endif 202 /* Number of scatter-gather DMA addr+len pairs after 203 * physical address coalescing is performed. 204 */ 205 unsigned short nr_phys_segments; 206 207 unsigned short ioprio; 208 209 int ref_count; 210 211 void *special; /* opaque pointer available for LLD use */ 212 char *buffer; /* kaddr of the current segment if available */ 213 214 int tag; 215 int errors; 216 217 /* 218 * when request is used as a packet command carrier 219 */ 220 unsigned char __cmd[BLK_MAX_CDB]; 221 unsigned char *cmd; 222 unsigned short cmd_len; 223 224 unsigned int extra_len; /* length of alignment and padding */ 225 unsigned int sense_len; 226 unsigned int resid_len; /* residual count */ 227 void *sense; 228 229 unsigned long deadline; 230 struct list_head timeout_list; 231 unsigned int timeout; 232 int retries; 233 234 /* 235 * completion callback. 236 */ 237 rq_end_io_fn *end_io; 238 void *end_io_data; 239 240 /* for bidi */ 241 struct request *next_rq; 242 }; 243 244 static inline unsigned short req_get_ioprio(struct request *req) 245 { 246 return req->ioprio; 247 } 248 249 /* 250 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME 251 * requests. Some step values could eventually be made generic. 252 */ 253 struct request_pm_state 254 { 255 /* PM state machine step value, currently driver specific */ 256 int pm_step; 257 /* requested PM state value (S1, S2, S3, S4, ...) */ 258 u32 pm_state; 259 void* data; /* for driver use */ 260 }; 261 262 #include <linux/elevator.h> 263 264 typedef void (request_fn_proc) (struct request_queue *q); 265 typedef int (make_request_fn) (struct request_queue *q, struct bio *bio); 266 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 267 typedef void (unplug_fn) (struct request_queue *); 268 269 struct bio_vec; 270 struct bvec_merge_data { 271 struct block_device *bi_bdev; 272 sector_t bi_sector; 273 unsigned bi_size; 274 unsigned long bi_rw; 275 }; 276 typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *, 277 struct bio_vec *); 278 typedef void (prepare_flush_fn) (struct request_queue *, struct request *); 279 typedef void (softirq_done_fn)(struct request *); 280 typedef int (dma_drain_needed_fn)(struct request *); 281 typedef int (lld_busy_fn) (struct request_queue *q); 282 283 enum blk_eh_timer_return { 284 BLK_EH_NOT_HANDLED, 285 BLK_EH_HANDLED, 286 BLK_EH_RESET_TIMER, 287 }; 288 289 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 290 291 enum blk_queue_state { 292 Queue_down, 293 Queue_up, 294 }; 295 296 struct blk_queue_tag { 297 struct request **tag_index; /* map of busy tags */ 298 unsigned long *tag_map; /* bit map of free/busy tags */ 299 int busy; /* current depth */ 300 int max_depth; /* what we will send to device */ 301 int real_max_depth; /* what the array can hold */ 302 atomic_t refcnt; /* map can be shared */ 303 }; 304 305 #define BLK_SCSI_MAX_CMDS (256) 306 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 307 308 struct queue_limits { 309 unsigned long bounce_pfn; 310 unsigned long seg_boundary_mask; 311 312 unsigned int max_hw_sectors; 313 unsigned int max_sectors; 314 unsigned int max_segment_size; 315 unsigned int physical_block_size; 316 unsigned int alignment_offset; 317 unsigned int io_min; 318 unsigned int io_opt; 319 unsigned int max_discard_sectors; 320 unsigned int discard_granularity; 321 unsigned int discard_alignment; 322 323 unsigned short logical_block_size; 324 unsigned short max_segments; 325 326 unsigned char misaligned; 327 unsigned char discard_misaligned; 328 unsigned char no_cluster; 329 signed char discard_zeroes_data; 330 }; 331 332 struct request_queue 333 { 334 /* 335 * Together with queue_head for cacheline sharing 336 */ 337 struct list_head queue_head; 338 struct request *last_merge; 339 struct elevator_queue *elevator; 340 341 /* 342 * the queue request freelist, one for reads and one for writes 343 */ 344 struct request_list rq; 345 346 request_fn_proc *request_fn; 347 make_request_fn *make_request_fn; 348 prep_rq_fn *prep_rq_fn; 349 unplug_fn *unplug_fn; 350 merge_bvec_fn *merge_bvec_fn; 351 prepare_flush_fn *prepare_flush_fn; 352 softirq_done_fn *softirq_done_fn; 353 rq_timed_out_fn *rq_timed_out_fn; 354 dma_drain_needed_fn *dma_drain_needed; 355 lld_busy_fn *lld_busy_fn; 356 357 /* 358 * Dispatch queue sorting 359 */ 360 sector_t end_sector; 361 struct request *boundary_rq; 362 363 /* 364 * Auto-unplugging state 365 */ 366 struct timer_list unplug_timer; 367 int unplug_thresh; /* After this many requests */ 368 unsigned long unplug_delay; /* After this many jiffies */ 369 struct work_struct unplug_work; 370 371 struct backing_dev_info backing_dev_info; 372 373 /* 374 * The queue owner gets to use this for whatever they like. 375 * ll_rw_blk doesn't touch it. 376 */ 377 void *queuedata; 378 379 /* 380 * queue needs bounce pages for pages above this limit 381 */ 382 gfp_t bounce_gfp; 383 384 /* 385 * various queue flags, see QUEUE_* below 386 */ 387 unsigned long queue_flags; 388 389 /* 390 * protects queue structures from reentrancy. ->__queue_lock should 391 * _never_ be used directly, it is queue private. always use 392 * ->queue_lock. 393 */ 394 spinlock_t __queue_lock; 395 spinlock_t *queue_lock; 396 397 /* 398 * queue kobject 399 */ 400 struct kobject kobj; 401 402 /* 403 * queue settings 404 */ 405 unsigned long nr_requests; /* Max # of requests */ 406 unsigned int nr_congestion_on; 407 unsigned int nr_congestion_off; 408 unsigned int nr_batching; 409 410 void *dma_drain_buffer; 411 unsigned int dma_drain_size; 412 unsigned int dma_pad_mask; 413 unsigned int dma_alignment; 414 415 struct blk_queue_tag *queue_tags; 416 struct list_head tag_busy_list; 417 418 unsigned int nr_sorted; 419 unsigned int in_flight[2]; 420 421 unsigned int rq_timeout; 422 struct timer_list timeout; 423 struct list_head timeout_list; 424 425 struct queue_limits limits; 426 427 /* 428 * sg stuff 429 */ 430 unsigned int sg_timeout; 431 unsigned int sg_reserved_size; 432 int node; 433 #ifdef CONFIG_BLK_DEV_IO_TRACE 434 struct blk_trace *blk_trace; 435 #endif 436 /* 437 * reserved for flush operations 438 */ 439 unsigned int ordered, next_ordered, ordseq; 440 int orderr, ordcolor; 441 struct request pre_flush_rq, bar_rq, post_flush_rq; 442 struct request *orig_bar_rq; 443 444 struct mutex sysfs_lock; 445 446 #if defined(CONFIG_BLK_DEV_BSG) 447 struct bsg_class_device bsg_dev; 448 #endif 449 }; 450 451 #define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */ 452 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 453 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 454 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 455 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 456 #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ 457 #define QUEUE_FLAG_REENTER 6 /* Re-entrancy avoidance */ 458 #define QUEUE_FLAG_PLUGGED 7 /* queue is plugged */ 459 #define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */ 460 #define QUEUE_FLAG_BIDI 9 /* queue supports bidi requests */ 461 #define QUEUE_FLAG_NOMERGES 10 /* disable merge attempts */ 462 #define QUEUE_FLAG_SAME_COMP 11 /* force complete on same CPU */ 463 #define QUEUE_FLAG_FAIL_IO 12 /* fake timeout */ 464 #define QUEUE_FLAG_STACKABLE 13 /* supports request stacking */ 465 #define QUEUE_FLAG_NONROT 14 /* non-rotational device (SSD) */ 466 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 467 #define QUEUE_FLAG_IO_STAT 15 /* do IO stats */ 468 #define QUEUE_FLAG_DISCARD 16 /* supports DISCARD */ 469 #define QUEUE_FLAG_NOXMERGES 17 /* No extended merges */ 470 471 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 472 (1 << QUEUE_FLAG_CLUSTER) | \ 473 (1 << QUEUE_FLAG_STACKABLE) | \ 474 (1 << QUEUE_FLAG_SAME_COMP)) 475 476 static inline int queue_is_locked(struct request_queue *q) 477 { 478 #ifdef CONFIG_SMP 479 spinlock_t *lock = q->queue_lock; 480 return lock && spin_is_locked(lock); 481 #else 482 return 1; 483 #endif 484 } 485 486 static inline void queue_flag_set_unlocked(unsigned int flag, 487 struct request_queue *q) 488 { 489 __set_bit(flag, &q->queue_flags); 490 } 491 492 static inline int queue_flag_test_and_clear(unsigned int flag, 493 struct request_queue *q) 494 { 495 WARN_ON_ONCE(!queue_is_locked(q)); 496 497 if (test_bit(flag, &q->queue_flags)) { 498 __clear_bit(flag, &q->queue_flags); 499 return 1; 500 } 501 502 return 0; 503 } 504 505 static inline int queue_flag_test_and_set(unsigned int flag, 506 struct request_queue *q) 507 { 508 WARN_ON_ONCE(!queue_is_locked(q)); 509 510 if (!test_bit(flag, &q->queue_flags)) { 511 __set_bit(flag, &q->queue_flags); 512 return 0; 513 } 514 515 return 1; 516 } 517 518 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 519 { 520 WARN_ON_ONCE(!queue_is_locked(q)); 521 __set_bit(flag, &q->queue_flags); 522 } 523 524 static inline void queue_flag_clear_unlocked(unsigned int flag, 525 struct request_queue *q) 526 { 527 __clear_bit(flag, &q->queue_flags); 528 } 529 530 static inline int queue_in_flight(struct request_queue *q) 531 { 532 return q->in_flight[0] + q->in_flight[1]; 533 } 534 535 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 536 { 537 WARN_ON_ONCE(!queue_is_locked(q)); 538 __clear_bit(flag, &q->queue_flags); 539 } 540 541 enum { 542 /* 543 * Hardbarrier is supported with one of the following methods. 544 * 545 * NONE : hardbarrier unsupported 546 * DRAIN : ordering by draining is enough 547 * DRAIN_FLUSH : ordering by draining w/ pre and post flushes 548 * DRAIN_FUA : ordering by draining w/ pre flush and FUA write 549 * TAG : ordering by tag is enough 550 * TAG_FLUSH : ordering by tag w/ pre and post flushes 551 * TAG_FUA : ordering by tag w/ pre flush and FUA write 552 */ 553 QUEUE_ORDERED_BY_DRAIN = 0x01, 554 QUEUE_ORDERED_BY_TAG = 0x02, 555 QUEUE_ORDERED_DO_PREFLUSH = 0x10, 556 QUEUE_ORDERED_DO_BAR = 0x20, 557 QUEUE_ORDERED_DO_POSTFLUSH = 0x40, 558 QUEUE_ORDERED_DO_FUA = 0x80, 559 560 QUEUE_ORDERED_NONE = 0x00, 561 562 QUEUE_ORDERED_DRAIN = QUEUE_ORDERED_BY_DRAIN | 563 QUEUE_ORDERED_DO_BAR, 564 QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN | 565 QUEUE_ORDERED_DO_PREFLUSH | 566 QUEUE_ORDERED_DO_POSTFLUSH, 567 QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN | 568 QUEUE_ORDERED_DO_PREFLUSH | 569 QUEUE_ORDERED_DO_FUA, 570 571 QUEUE_ORDERED_TAG = QUEUE_ORDERED_BY_TAG | 572 QUEUE_ORDERED_DO_BAR, 573 QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG | 574 QUEUE_ORDERED_DO_PREFLUSH | 575 QUEUE_ORDERED_DO_POSTFLUSH, 576 QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG | 577 QUEUE_ORDERED_DO_PREFLUSH | 578 QUEUE_ORDERED_DO_FUA, 579 580 /* 581 * Ordered operation sequence 582 */ 583 QUEUE_ORDSEQ_STARTED = 0x01, /* flushing in progress */ 584 QUEUE_ORDSEQ_DRAIN = 0x02, /* waiting for the queue to be drained */ 585 QUEUE_ORDSEQ_PREFLUSH = 0x04, /* pre-flushing in progress */ 586 QUEUE_ORDSEQ_BAR = 0x08, /* original barrier req in progress */ 587 QUEUE_ORDSEQ_POSTFLUSH = 0x10, /* post-flushing in progress */ 588 QUEUE_ORDSEQ_DONE = 0x20, 589 }; 590 591 #define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags) 592 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 593 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 594 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 595 #define blk_queue_noxmerges(q) \ 596 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 597 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 598 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 599 #define blk_queue_flushing(q) ((q)->ordseq) 600 #define blk_queue_stackable(q) \ 601 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 602 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 603 604 #define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS) 605 #define blk_pc_request(rq) ((rq)->cmd_type == REQ_TYPE_BLOCK_PC) 606 #define blk_special_request(rq) ((rq)->cmd_type == REQ_TYPE_SPECIAL) 607 #define blk_sense_request(rq) ((rq)->cmd_type == REQ_TYPE_SENSE) 608 609 #define blk_failfast_dev(rq) ((rq)->cmd_flags & REQ_FAILFAST_DEV) 610 #define blk_failfast_transport(rq) ((rq)->cmd_flags & REQ_FAILFAST_TRANSPORT) 611 #define blk_failfast_driver(rq) ((rq)->cmd_flags & REQ_FAILFAST_DRIVER) 612 #define blk_noretry_request(rq) (blk_failfast_dev(rq) || \ 613 blk_failfast_transport(rq) || \ 614 blk_failfast_driver(rq)) 615 #define blk_rq_started(rq) ((rq)->cmd_flags & REQ_STARTED) 616 #define blk_rq_io_stat(rq) ((rq)->cmd_flags & REQ_IO_STAT) 617 #define blk_rq_quiet(rq) ((rq)->cmd_flags & REQ_QUIET) 618 619 #define blk_account_rq(rq) (blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq))) 620 621 #define blk_pm_suspend_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND) 622 #define blk_pm_resume_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_RESUME) 623 #define blk_pm_request(rq) \ 624 (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq)) 625 626 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 627 #define blk_sorted_rq(rq) ((rq)->cmd_flags & REQ_SORTED) 628 #define blk_barrier_rq(rq) ((rq)->cmd_flags & REQ_HARDBARRIER) 629 #define blk_fua_rq(rq) ((rq)->cmd_flags & REQ_FUA) 630 #define blk_discard_rq(rq) ((rq)->cmd_flags & REQ_DISCARD) 631 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 632 /* rq->queuelist of dequeued request must be list_empty() */ 633 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 634 635 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 636 637 #define rq_data_dir(rq) ((rq)->cmd_flags & 1) 638 639 /* 640 * We regard a request as sync, if either a read or a sync write 641 */ 642 static inline bool rw_is_sync(unsigned int rw_flags) 643 { 644 return !(rw_flags & REQ_RW) || (rw_flags & REQ_RW_SYNC); 645 } 646 647 static inline bool rq_is_sync(struct request *rq) 648 { 649 return rw_is_sync(rq->cmd_flags); 650 } 651 652 #define rq_is_meta(rq) ((rq)->cmd_flags & REQ_RW_META) 653 #define rq_noidle(rq) ((rq)->cmd_flags & REQ_NOIDLE) 654 655 static inline int blk_queue_full(struct request_queue *q, int sync) 656 { 657 if (sync) 658 return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags); 659 return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags); 660 } 661 662 static inline void blk_set_queue_full(struct request_queue *q, int sync) 663 { 664 if (sync) 665 queue_flag_set(QUEUE_FLAG_SYNCFULL, q); 666 else 667 queue_flag_set(QUEUE_FLAG_ASYNCFULL, q); 668 } 669 670 static inline void blk_clear_queue_full(struct request_queue *q, int sync) 671 { 672 if (sync) 673 queue_flag_clear(QUEUE_FLAG_SYNCFULL, q); 674 else 675 queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q); 676 } 677 678 679 /* 680 * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may 681 * it already be started by driver. 682 */ 683 #define RQ_NOMERGE_FLAGS \ 684 (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER) 685 #define rq_mergeable(rq) \ 686 (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \ 687 (blk_discard_rq(rq) || blk_fs_request((rq)))) 688 689 /* 690 * q->prep_rq_fn return values 691 */ 692 #define BLKPREP_OK 0 /* serve it */ 693 #define BLKPREP_KILL 1 /* fatal error, kill */ 694 #define BLKPREP_DEFER 2 /* leave on queue */ 695 696 extern unsigned long blk_max_low_pfn, blk_max_pfn; 697 698 /* 699 * standard bounce addresses: 700 * 701 * BLK_BOUNCE_HIGH : bounce all highmem pages 702 * BLK_BOUNCE_ANY : don't bounce anything 703 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 704 */ 705 706 #if BITS_PER_LONG == 32 707 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 708 #else 709 #define BLK_BOUNCE_HIGH -1ULL 710 #endif 711 #define BLK_BOUNCE_ANY (-1ULL) 712 #define BLK_BOUNCE_ISA (ISA_DMA_THRESHOLD) 713 714 /* 715 * default timeout for SG_IO if none specified 716 */ 717 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 718 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 719 720 #ifdef CONFIG_BOUNCE 721 extern int init_emergency_isa_pool(void); 722 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 723 #else 724 static inline int init_emergency_isa_pool(void) 725 { 726 return 0; 727 } 728 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 729 { 730 } 731 #endif /* CONFIG_MMU */ 732 733 struct rq_map_data { 734 struct page **pages; 735 int page_order; 736 int nr_entries; 737 unsigned long offset; 738 int null_mapped; 739 int from_user; 740 }; 741 742 struct req_iterator { 743 int i; 744 struct bio *bio; 745 }; 746 747 /* This should not be used directly - use rq_for_each_segment */ 748 #define for_each_bio(_bio) \ 749 for (; _bio; _bio = _bio->bi_next) 750 #define __rq_for_each_bio(_bio, rq) \ 751 if ((rq->bio)) \ 752 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 753 754 #define rq_for_each_segment(bvl, _rq, _iter) \ 755 __rq_for_each_bio(_iter.bio, _rq) \ 756 bio_for_each_segment(bvl, _iter.bio, _iter.i) 757 758 #define rq_iter_last(rq, _iter) \ 759 (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1) 760 761 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 762 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 763 #endif 764 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 765 extern void rq_flush_dcache_pages(struct request *rq); 766 #else 767 static inline void rq_flush_dcache_pages(struct request *rq) 768 { 769 } 770 #endif 771 772 extern int blk_register_queue(struct gendisk *disk); 773 extern void blk_unregister_queue(struct gendisk *disk); 774 extern void register_disk(struct gendisk *dev); 775 extern void generic_make_request(struct bio *bio); 776 extern void blk_rq_init(struct request_queue *q, struct request *rq); 777 extern void blk_put_request(struct request *); 778 extern void __blk_put_request(struct request_queue *, struct request *); 779 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 780 extern struct request *blk_make_request(struct request_queue *, struct bio *, 781 gfp_t); 782 extern void blk_insert_request(struct request_queue *, struct request *, int, void *); 783 extern void blk_requeue_request(struct request_queue *, struct request *); 784 extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); 785 extern int blk_lld_busy(struct request_queue *q); 786 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 787 struct bio_set *bs, gfp_t gfp_mask, 788 int (*bio_ctr)(struct bio *, struct bio *, void *), 789 void *data); 790 extern void blk_rq_unprep_clone(struct request *rq); 791 extern int blk_insert_cloned_request(struct request_queue *q, 792 struct request *rq); 793 extern void blk_plug_device(struct request_queue *); 794 extern void blk_plug_device_unlocked(struct request_queue *); 795 extern int blk_remove_plug(struct request_queue *); 796 extern void blk_recount_segments(struct request_queue *, struct bio *); 797 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 798 unsigned int, void __user *); 799 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 800 struct scsi_ioctl_command __user *); 801 802 /* 803 * A queue has just exitted congestion. Note this in the global counter of 804 * congested queues, and wake up anyone who was waiting for requests to be 805 * put back. 806 */ 807 static inline void blk_clear_queue_congested(struct request_queue *q, int sync) 808 { 809 clear_bdi_congested(&q->backing_dev_info, sync); 810 } 811 812 /* 813 * A queue has just entered congestion. Flag that in the queue's VM-visible 814 * state flags and increment the global gounter of congested queues. 815 */ 816 static inline void blk_set_queue_congested(struct request_queue *q, int sync) 817 { 818 set_bdi_congested(&q->backing_dev_info, sync); 819 } 820 821 extern void blk_start_queue(struct request_queue *q); 822 extern void blk_stop_queue(struct request_queue *q); 823 extern void blk_sync_queue(struct request_queue *q); 824 extern void __blk_stop_queue(struct request_queue *q); 825 extern void __blk_run_queue(struct request_queue *); 826 extern void blk_run_queue(struct request_queue *); 827 extern int blk_rq_map_user(struct request_queue *, struct request *, 828 struct rq_map_data *, void __user *, unsigned long, 829 gfp_t); 830 extern int blk_rq_unmap_user(struct bio *); 831 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 832 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 833 struct rq_map_data *, struct sg_iovec *, int, 834 unsigned int, gfp_t); 835 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 836 struct request *, int); 837 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 838 struct request *, int, rq_end_io_fn *); 839 extern void blk_unplug(struct request_queue *q); 840 841 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 842 { 843 return bdev->bd_disk->queue; 844 } 845 846 /* 847 * blk_rq_pos() : the current sector 848 * blk_rq_bytes() : bytes left in the entire request 849 * blk_rq_cur_bytes() : bytes left in the current segment 850 * blk_rq_err_bytes() : bytes left till the next error boundary 851 * blk_rq_sectors() : sectors left in the entire request 852 * blk_rq_cur_sectors() : sectors left in the current segment 853 */ 854 static inline sector_t blk_rq_pos(const struct request *rq) 855 { 856 return rq->__sector; 857 } 858 859 static inline unsigned int blk_rq_bytes(const struct request *rq) 860 { 861 return rq->__data_len; 862 } 863 864 static inline int blk_rq_cur_bytes(const struct request *rq) 865 { 866 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 867 } 868 869 extern unsigned int blk_rq_err_bytes(const struct request *rq); 870 871 static inline unsigned int blk_rq_sectors(const struct request *rq) 872 { 873 return blk_rq_bytes(rq) >> 9; 874 } 875 876 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 877 { 878 return blk_rq_cur_bytes(rq) >> 9; 879 } 880 881 /* 882 * Request issue related functions. 883 */ 884 extern struct request *blk_peek_request(struct request_queue *q); 885 extern void blk_start_request(struct request *rq); 886 extern struct request *blk_fetch_request(struct request_queue *q); 887 888 /* 889 * Request completion related functions. 890 * 891 * blk_update_request() completes given number of bytes and updates 892 * the request without completing it. 893 * 894 * blk_end_request() and friends. __blk_end_request() must be called 895 * with the request queue spinlock acquired. 896 * 897 * Several drivers define their own end_request and call 898 * blk_end_request() for parts of the original function. 899 * This prevents code duplication in drivers. 900 */ 901 extern bool blk_update_request(struct request *rq, int error, 902 unsigned int nr_bytes); 903 extern bool blk_end_request(struct request *rq, int error, 904 unsigned int nr_bytes); 905 extern void blk_end_request_all(struct request *rq, int error); 906 extern bool blk_end_request_cur(struct request *rq, int error); 907 extern bool blk_end_request_err(struct request *rq, int error); 908 extern bool __blk_end_request(struct request *rq, int error, 909 unsigned int nr_bytes); 910 extern void __blk_end_request_all(struct request *rq, int error); 911 extern bool __blk_end_request_cur(struct request *rq, int error); 912 extern bool __blk_end_request_err(struct request *rq, int error); 913 914 extern void blk_complete_request(struct request *); 915 extern void __blk_complete_request(struct request *); 916 extern void blk_abort_request(struct request *); 917 extern void blk_abort_queue(struct request_queue *); 918 919 /* 920 * Access functions for manipulating queue properties 921 */ 922 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 923 spinlock_t *lock, int node_id); 924 extern struct request_queue *blk_init_allocated_queue_node(struct request_queue *, 925 request_fn_proc *, 926 spinlock_t *, int node_id); 927 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 928 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 929 request_fn_proc *, spinlock_t *); 930 extern void blk_cleanup_queue(struct request_queue *); 931 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 932 extern void blk_queue_bounce_limit(struct request_queue *, u64); 933 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 934 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 935 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 936 extern void blk_queue_max_discard_sectors(struct request_queue *q, 937 unsigned int max_discard_sectors); 938 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 939 extern void blk_queue_physical_block_size(struct request_queue *, unsigned short); 940 extern void blk_queue_alignment_offset(struct request_queue *q, 941 unsigned int alignment); 942 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 943 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 944 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 945 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 946 extern void blk_set_default_limits(struct queue_limits *lim); 947 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 948 sector_t offset); 949 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 950 sector_t offset); 951 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 952 sector_t offset); 953 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 954 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 955 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 956 extern int blk_queue_dma_drain(struct request_queue *q, 957 dma_drain_needed_fn *dma_drain_needed, 958 void *buf, unsigned int size); 959 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 960 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 961 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 962 extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); 963 extern void blk_queue_dma_alignment(struct request_queue *, int); 964 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 965 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 966 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 967 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 968 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 969 extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *); 970 extern bool blk_do_ordered(struct request_queue *, struct request **); 971 extern unsigned blk_ordered_cur_seq(struct request_queue *); 972 extern unsigned blk_ordered_req_seq(struct request *); 973 extern bool blk_ordered_complete_seq(struct request_queue *, unsigned, int); 974 975 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 976 extern void blk_dump_rq_flags(struct request *, char *); 977 extern void generic_unplug_device(struct request_queue *); 978 extern long nr_blockdev_pages(void); 979 980 int blk_get_queue(struct request_queue *); 981 struct request_queue *blk_alloc_queue(gfp_t); 982 struct request_queue *blk_alloc_queue_node(gfp_t, int); 983 extern void blk_put_queue(struct request_queue *); 984 985 /* 986 * tag stuff 987 */ 988 #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED) 989 extern int blk_queue_start_tag(struct request_queue *, struct request *); 990 extern struct request *blk_queue_find_tag(struct request_queue *, int); 991 extern void blk_queue_end_tag(struct request_queue *, struct request *); 992 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *); 993 extern void blk_queue_free_tags(struct request_queue *); 994 extern int blk_queue_resize_tags(struct request_queue *, int); 995 extern void blk_queue_invalidate_tags(struct request_queue *); 996 extern struct blk_queue_tag *blk_init_tags(int); 997 extern void blk_free_tags(struct blk_queue_tag *); 998 999 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 1000 int tag) 1001 { 1002 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 1003 return NULL; 1004 return bqt->tag_index[tag]; 1005 } 1006 enum{ 1007 BLKDEV_WAIT, /* wait for completion */ 1008 BLKDEV_BARRIER, /*issue request with barrier */ 1009 }; 1010 #define BLKDEV_IFL_WAIT (1 << BLKDEV_WAIT) 1011 #define BLKDEV_IFL_BARRIER (1 << BLKDEV_BARRIER) 1012 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *, 1013 unsigned long); 1014 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1015 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 1016 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1017 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 1018 static inline int sb_issue_discard(struct super_block *sb, 1019 sector_t block, sector_t nr_blocks) 1020 { 1021 block <<= (sb->s_blocksize_bits - 9); 1022 nr_blocks <<= (sb->s_blocksize_bits - 9); 1023 return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_KERNEL, 1024 BLKDEV_IFL_WAIT | BLKDEV_IFL_BARRIER); 1025 } 1026 1027 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 1028 1029 enum blk_default_limits { 1030 BLK_MAX_SEGMENTS = 128, 1031 BLK_SAFE_MAX_SECTORS = 255, 1032 BLK_DEF_MAX_SECTORS = 1024, 1033 BLK_MAX_SEGMENT_SIZE = 65536, 1034 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 1035 }; 1036 1037 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1038 1039 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 1040 { 1041 return q->limits.bounce_pfn; 1042 } 1043 1044 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1045 { 1046 return q->limits.seg_boundary_mask; 1047 } 1048 1049 static inline unsigned int queue_max_sectors(struct request_queue *q) 1050 { 1051 return q->limits.max_sectors; 1052 } 1053 1054 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1055 { 1056 return q->limits.max_hw_sectors; 1057 } 1058 1059 static inline unsigned short queue_max_segments(struct request_queue *q) 1060 { 1061 return q->limits.max_segments; 1062 } 1063 1064 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1065 { 1066 return q->limits.max_segment_size; 1067 } 1068 1069 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1070 { 1071 int retval = 512; 1072 1073 if (q && q->limits.logical_block_size) 1074 retval = q->limits.logical_block_size; 1075 1076 return retval; 1077 } 1078 1079 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1080 { 1081 return queue_logical_block_size(bdev_get_queue(bdev)); 1082 } 1083 1084 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1085 { 1086 return q->limits.physical_block_size; 1087 } 1088 1089 static inline int bdev_physical_block_size(struct block_device *bdev) 1090 { 1091 return queue_physical_block_size(bdev_get_queue(bdev)); 1092 } 1093 1094 static inline unsigned int queue_io_min(struct request_queue *q) 1095 { 1096 return q->limits.io_min; 1097 } 1098 1099 static inline int bdev_io_min(struct block_device *bdev) 1100 { 1101 return queue_io_min(bdev_get_queue(bdev)); 1102 } 1103 1104 static inline unsigned int queue_io_opt(struct request_queue *q) 1105 { 1106 return q->limits.io_opt; 1107 } 1108 1109 static inline int bdev_io_opt(struct block_device *bdev) 1110 { 1111 return queue_io_opt(bdev_get_queue(bdev)); 1112 } 1113 1114 static inline int queue_alignment_offset(struct request_queue *q) 1115 { 1116 if (q->limits.misaligned) 1117 return -1; 1118 1119 return q->limits.alignment_offset; 1120 } 1121 1122 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1123 { 1124 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1125 unsigned int alignment = (sector << 9) & (granularity - 1); 1126 1127 return (granularity + lim->alignment_offset - alignment) 1128 & (granularity - 1); 1129 } 1130 1131 static inline int bdev_alignment_offset(struct block_device *bdev) 1132 { 1133 struct request_queue *q = bdev_get_queue(bdev); 1134 1135 if (q->limits.misaligned) 1136 return -1; 1137 1138 if (bdev != bdev->bd_contains) 1139 return bdev->bd_part->alignment_offset; 1140 1141 return q->limits.alignment_offset; 1142 } 1143 1144 static inline int queue_discard_alignment(struct request_queue *q) 1145 { 1146 if (q->limits.discard_misaligned) 1147 return -1; 1148 1149 return q->limits.discard_alignment; 1150 } 1151 1152 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1153 { 1154 unsigned int alignment = (sector << 9) & (lim->discard_granularity - 1); 1155 1156 return (lim->discard_granularity + lim->discard_alignment - alignment) 1157 & (lim->discard_granularity - 1); 1158 } 1159 1160 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1161 { 1162 if (q->limits.discard_zeroes_data == 1) 1163 return 1; 1164 1165 return 0; 1166 } 1167 1168 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1169 { 1170 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1171 } 1172 1173 static inline int queue_dma_alignment(struct request_queue *q) 1174 { 1175 return q ? q->dma_alignment : 511; 1176 } 1177 1178 static inline int blk_rq_aligned(struct request_queue *q, void *addr, 1179 unsigned int len) 1180 { 1181 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1182 return !((unsigned long)addr & alignment) && !(len & alignment); 1183 } 1184 1185 /* assumes size > 256 */ 1186 static inline unsigned int blksize_bits(unsigned int size) 1187 { 1188 unsigned int bits = 8; 1189 do { 1190 bits++; 1191 size >>= 1; 1192 } while (size > 256); 1193 return bits; 1194 } 1195 1196 static inline unsigned int block_size(struct block_device *bdev) 1197 { 1198 return bdev->bd_block_size; 1199 } 1200 1201 typedef struct {struct page *v;} Sector; 1202 1203 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1204 1205 static inline void put_dev_sector(Sector p) 1206 { 1207 page_cache_release(p.v); 1208 } 1209 1210 struct work_struct; 1211 int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); 1212 1213 #ifdef CONFIG_BLK_CGROUP 1214 /* 1215 * This should not be using sched_clock(). A real patch is in progress 1216 * to fix this up, until that is in place we need to disable preemption 1217 * around sched_clock() in this function and set_io_start_time_ns(). 1218 */ 1219 static inline void set_start_time_ns(struct request *req) 1220 { 1221 preempt_disable(); 1222 req->start_time_ns = sched_clock(); 1223 preempt_enable(); 1224 } 1225 1226 static inline void set_io_start_time_ns(struct request *req) 1227 { 1228 preempt_disable(); 1229 req->io_start_time_ns = sched_clock(); 1230 preempt_enable(); 1231 } 1232 1233 static inline uint64_t rq_start_time_ns(struct request *req) 1234 { 1235 return req->start_time_ns; 1236 } 1237 1238 static inline uint64_t rq_io_start_time_ns(struct request *req) 1239 { 1240 return req->io_start_time_ns; 1241 } 1242 #else 1243 static inline void set_start_time_ns(struct request *req) {} 1244 static inline void set_io_start_time_ns(struct request *req) {} 1245 static inline uint64_t rq_start_time_ns(struct request *req) 1246 { 1247 return 0; 1248 } 1249 static inline uint64_t rq_io_start_time_ns(struct request *req) 1250 { 1251 return 0; 1252 } 1253 #endif 1254 1255 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1256 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1257 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1258 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1259 1260 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1261 1262 #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */ 1263 #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */ 1264 1265 struct blk_integrity_exchg { 1266 void *prot_buf; 1267 void *data_buf; 1268 sector_t sector; 1269 unsigned int data_size; 1270 unsigned short sector_size; 1271 const char *disk_name; 1272 }; 1273 1274 typedef void (integrity_gen_fn) (struct blk_integrity_exchg *); 1275 typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *); 1276 typedef void (integrity_set_tag_fn) (void *, void *, unsigned int); 1277 typedef void (integrity_get_tag_fn) (void *, void *, unsigned int); 1278 1279 struct blk_integrity { 1280 integrity_gen_fn *generate_fn; 1281 integrity_vrfy_fn *verify_fn; 1282 integrity_set_tag_fn *set_tag_fn; 1283 integrity_get_tag_fn *get_tag_fn; 1284 1285 unsigned short flags; 1286 unsigned short tuple_size; 1287 unsigned short sector_size; 1288 unsigned short tag_size; 1289 1290 const char *name; 1291 1292 struct kobject kobj; 1293 }; 1294 1295 extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); 1296 extern void blk_integrity_unregister(struct gendisk *); 1297 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1298 extern int blk_rq_map_integrity_sg(struct request *, struct scatterlist *); 1299 extern int blk_rq_count_integrity_sg(struct request *); 1300 1301 static inline 1302 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1303 { 1304 return bdev->bd_disk->integrity; 1305 } 1306 1307 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1308 { 1309 return disk->integrity; 1310 } 1311 1312 static inline int blk_integrity_rq(struct request *rq) 1313 { 1314 if (rq->bio == NULL) 1315 return 0; 1316 1317 return bio_integrity(rq->bio); 1318 } 1319 1320 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1321 1322 #define blk_integrity_rq(rq) (0) 1323 #define blk_rq_count_integrity_sg(a) (0) 1324 #define blk_rq_map_integrity_sg(a, b) (0) 1325 #define bdev_get_integrity(a) (0) 1326 #define blk_get_integrity(a) (0) 1327 #define blk_integrity_compare(a, b) (0) 1328 #define blk_integrity_register(a, b) (0) 1329 #define blk_integrity_unregister(a) do { } while (0); 1330 1331 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1332 1333 struct block_device_operations { 1334 int (*open) (struct block_device *, fmode_t); 1335 int (*release) (struct gendisk *, fmode_t); 1336 int (*locked_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1337 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1338 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1339 int (*direct_access) (struct block_device *, sector_t, 1340 void **, unsigned long *); 1341 int (*media_changed) (struct gendisk *); 1342 void (*unlock_native_capacity) (struct gendisk *); 1343 int (*revalidate_disk) (struct gendisk *); 1344 int (*getgeo)(struct block_device *, struct hd_geometry *); 1345 /* this callback is with swap_lock and sometimes page table lock held */ 1346 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1347 struct module *owner; 1348 }; 1349 1350 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1351 unsigned long); 1352 #else /* CONFIG_BLOCK */ 1353 /* 1354 * stubs for when the block layer is configured out 1355 */ 1356 #define buffer_heads_over_limit 0 1357 1358 static inline long nr_blockdev_pages(void) 1359 { 1360 return 0; 1361 } 1362 1363 #endif /* CONFIG_BLOCK */ 1364 1365 #endif 1366