1 #ifndef _LINUX_BLKDEV_H 2 #define _LINUX_BLKDEV_H 3 4 #include <linux/sched.h> 5 6 #ifdef CONFIG_BLOCK 7 8 #include <linux/major.h> 9 #include <linux/genhd.h> 10 #include <linux/list.h> 11 #include <linux/llist.h> 12 #include <linux/timer.h> 13 #include <linux/workqueue.h> 14 #include <linux/pagemap.h> 15 #include <linux/backing-dev-defs.h> 16 #include <linux/wait.h> 17 #include <linux/mempool.h> 18 #include <linux/pfn.h> 19 #include <linux/bio.h> 20 #include <linux/stringify.h> 21 #include <linux/gfp.h> 22 #include <linux/bsg.h> 23 #include <linux/smp.h> 24 #include <linux/rcupdate.h> 25 #include <linux/percpu-refcount.h> 26 #include <linux/scatterlist.h> 27 #include <linux/blkzoned.h> 28 29 struct module; 30 struct scsi_ioctl_command; 31 32 struct request_queue; 33 struct elevator_queue; 34 struct blk_trace; 35 struct request; 36 struct sg_io_hdr; 37 struct bsg_job; 38 struct blkcg_gq; 39 struct blk_flush_queue; 40 struct pr_ops; 41 struct rq_wb; 42 43 #define BLKDEV_MIN_RQ 4 44 #define BLKDEV_MAX_RQ 128 /* Default maximum */ 45 46 /* 47 * Maximum number of blkcg policies allowed to be registered concurrently. 48 * Defined here to simplify include dependency. 49 */ 50 #define BLKCG_MAX_POLS 2 51 52 typedef void (rq_end_io_fn)(struct request *, int); 53 54 #define BLK_RL_SYNCFULL (1U << 0) 55 #define BLK_RL_ASYNCFULL (1U << 1) 56 57 struct request_list { 58 struct request_queue *q; /* the queue this rl belongs to */ 59 #ifdef CONFIG_BLK_CGROUP 60 struct blkcg_gq *blkg; /* blkg this request pool belongs to */ 61 #endif 62 /* 63 * count[], starved[], and wait[] are indexed by 64 * BLK_RW_SYNC/BLK_RW_ASYNC 65 */ 66 int count[2]; 67 int starved[2]; 68 mempool_t *rq_pool; 69 wait_queue_head_t wait[2]; 70 unsigned int flags; 71 }; 72 73 /* 74 * request command types 75 */ 76 enum rq_cmd_type_bits { 77 REQ_TYPE_FS = 1, /* fs request */ 78 REQ_TYPE_BLOCK_PC, /* scsi command */ 79 REQ_TYPE_DRV_PRIV, /* driver defined types from here */ 80 }; 81 82 /* 83 * request flags */ 84 typedef __u32 __bitwise req_flags_t; 85 86 /* elevator knows about this request */ 87 #define RQF_SORTED ((__force req_flags_t)(1 << 0)) 88 /* drive already may have started this one */ 89 #define RQF_STARTED ((__force req_flags_t)(1 << 1)) 90 /* uses tagged queueing */ 91 #define RQF_QUEUED ((__force req_flags_t)(1 << 2)) 92 /* may not be passed by ioscheduler */ 93 #define RQF_SOFTBARRIER ((__force req_flags_t)(1 << 3)) 94 /* request for flush sequence */ 95 #define RQF_FLUSH_SEQ ((__force req_flags_t)(1 << 4)) 96 /* merge of different types, fail separately */ 97 #define RQF_MIXED_MERGE ((__force req_flags_t)(1 << 5)) 98 /* track inflight for MQ */ 99 #define RQF_MQ_INFLIGHT ((__force req_flags_t)(1 << 6)) 100 /* don't call prep for this one */ 101 #define RQF_DONTPREP ((__force req_flags_t)(1 << 7)) 102 /* set for "ide_preempt" requests and also for requests for which the SCSI 103 "quiesce" state must be ignored. */ 104 #define RQF_PREEMPT ((__force req_flags_t)(1 << 8)) 105 /* contains copies of user pages */ 106 #define RQF_COPY_USER ((__force req_flags_t)(1 << 9)) 107 /* vaguely specified driver internal error. Ignored by the block layer */ 108 #define RQF_FAILED ((__force req_flags_t)(1 << 10)) 109 /* don't warn about errors */ 110 #define RQF_QUIET ((__force req_flags_t)(1 << 11)) 111 /* elevator private data attached */ 112 #define RQF_ELVPRIV ((__force req_flags_t)(1 << 12)) 113 /* account I/O stat */ 114 #define RQF_IO_STAT ((__force req_flags_t)(1 << 13)) 115 /* request came from our alloc pool */ 116 #define RQF_ALLOCED ((__force req_flags_t)(1 << 14)) 117 /* runtime pm request */ 118 #define RQF_PM ((__force req_flags_t)(1 << 15)) 119 /* on IO scheduler merge hash */ 120 #define RQF_HASHED ((__force req_flags_t)(1 << 16)) 121 /* IO stats tracking on */ 122 #define RQF_STATS ((__force req_flags_t)(1 << 17)) 123 /* Look at ->special_vec for the actual data payload instead of the 124 bio chain. */ 125 #define RQF_SPECIAL_PAYLOAD ((__force req_flags_t)(1 << 18)) 126 127 /* flags that prevent us from merging requests: */ 128 #define RQF_NOMERGE_FLAGS \ 129 (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD) 130 131 #define BLK_MAX_CDB 16 132 133 /* 134 * Try to put the fields that are referenced together in the same cacheline. 135 * 136 * If you modify this structure, make sure to update blk_rq_init() and 137 * especially blk_mq_rq_ctx_init() to take care of the added fields. 138 */ 139 struct request { 140 struct list_head queuelist; 141 union { 142 struct call_single_data csd; 143 u64 fifo_time; 144 }; 145 146 struct request_queue *q; 147 struct blk_mq_ctx *mq_ctx; 148 149 int cpu; 150 unsigned cmd_type; 151 unsigned int cmd_flags; /* op and common flags */ 152 req_flags_t rq_flags; 153 unsigned long atomic_flags; 154 155 /* the following two fields are internal, NEVER access directly */ 156 unsigned int __data_len; /* total data len */ 157 sector_t __sector; /* sector cursor */ 158 159 struct bio *bio; 160 struct bio *biotail; 161 162 /* 163 * The hash is used inside the scheduler, and killed once the 164 * request reaches the dispatch list. The ipi_list is only used 165 * to queue the request for softirq completion, which is long 166 * after the request has been unhashed (and even removed from 167 * the dispatch list). 168 */ 169 union { 170 struct hlist_node hash; /* merge hash */ 171 struct list_head ipi_list; 172 }; 173 174 /* 175 * The rb_node is only used inside the io scheduler, requests 176 * are pruned when moved to the dispatch queue. So let the 177 * completion_data share space with the rb_node. 178 */ 179 union { 180 struct rb_node rb_node; /* sort/lookup */ 181 struct bio_vec special_vec; 182 void *completion_data; 183 }; 184 185 /* 186 * Three pointers are available for the IO schedulers, if they need 187 * more they have to dynamically allocate it. Flush requests are 188 * never put on the IO scheduler. So let the flush fields share 189 * space with the elevator data. 190 */ 191 union { 192 struct { 193 struct io_cq *icq; 194 void *priv[2]; 195 } elv; 196 197 struct { 198 unsigned int seq; 199 struct list_head list; 200 rq_end_io_fn *saved_end_io; 201 } flush; 202 }; 203 204 struct gendisk *rq_disk; 205 struct hd_struct *part; 206 unsigned long start_time; 207 struct blk_issue_stat issue_stat; 208 #ifdef CONFIG_BLK_CGROUP 209 struct request_list *rl; /* rl this rq is alloced from */ 210 unsigned long long start_time_ns; 211 unsigned long long io_start_time_ns; /* when passed to hardware */ 212 #endif 213 /* Number of scatter-gather DMA addr+len pairs after 214 * physical address coalescing is performed. 215 */ 216 unsigned short nr_phys_segments; 217 #if defined(CONFIG_BLK_DEV_INTEGRITY) 218 unsigned short nr_integrity_segments; 219 #endif 220 221 unsigned short ioprio; 222 223 void *special; /* opaque pointer available for LLD use */ 224 225 int tag; 226 int errors; 227 228 /* 229 * when request is used as a packet command carrier 230 */ 231 unsigned char __cmd[BLK_MAX_CDB]; 232 unsigned char *cmd; 233 unsigned short cmd_len; 234 235 unsigned int extra_len; /* length of alignment and padding */ 236 unsigned int sense_len; 237 unsigned int resid_len; /* residual count */ 238 void *sense; 239 240 unsigned long deadline; 241 struct list_head timeout_list; 242 unsigned int timeout; 243 int retries; 244 245 /* 246 * completion callback. 247 */ 248 rq_end_io_fn *end_io; 249 void *end_io_data; 250 251 /* for bidi */ 252 struct request *next_rq; 253 }; 254 255 static inline unsigned short req_get_ioprio(struct request *req) 256 { 257 return req->ioprio; 258 } 259 260 #include <linux/elevator.h> 261 262 struct blk_queue_ctx; 263 264 typedef void (request_fn_proc) (struct request_queue *q); 265 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio); 266 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 267 typedef void (unprep_rq_fn) (struct request_queue *, struct request *); 268 269 struct bio_vec; 270 typedef void (softirq_done_fn)(struct request *); 271 typedef int (dma_drain_needed_fn)(struct request *); 272 typedef int (lld_busy_fn) (struct request_queue *q); 273 typedef int (bsg_job_fn) (struct bsg_job *); 274 275 enum blk_eh_timer_return { 276 BLK_EH_NOT_HANDLED, 277 BLK_EH_HANDLED, 278 BLK_EH_RESET_TIMER, 279 }; 280 281 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 282 283 enum blk_queue_state { 284 Queue_down, 285 Queue_up, 286 }; 287 288 struct blk_queue_tag { 289 struct request **tag_index; /* map of busy tags */ 290 unsigned long *tag_map; /* bit map of free/busy tags */ 291 int busy; /* current depth */ 292 int max_depth; /* what we will send to device */ 293 int real_max_depth; /* what the array can hold */ 294 atomic_t refcnt; /* map can be shared */ 295 int alloc_policy; /* tag allocation policy */ 296 int next_tag; /* next tag */ 297 }; 298 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */ 299 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */ 300 301 #define BLK_SCSI_MAX_CMDS (256) 302 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 303 304 /* 305 * Zoned block device models (zoned limit). 306 */ 307 enum blk_zoned_model { 308 BLK_ZONED_NONE, /* Regular block device */ 309 BLK_ZONED_HA, /* Host-aware zoned block device */ 310 BLK_ZONED_HM, /* Host-managed zoned block device */ 311 }; 312 313 struct queue_limits { 314 unsigned long bounce_pfn; 315 unsigned long seg_boundary_mask; 316 unsigned long virt_boundary_mask; 317 318 unsigned int max_hw_sectors; 319 unsigned int max_dev_sectors; 320 unsigned int chunk_sectors; 321 unsigned int max_sectors; 322 unsigned int max_segment_size; 323 unsigned int physical_block_size; 324 unsigned int alignment_offset; 325 unsigned int io_min; 326 unsigned int io_opt; 327 unsigned int max_discard_sectors; 328 unsigned int max_hw_discard_sectors; 329 unsigned int max_write_same_sectors; 330 unsigned int max_write_zeroes_sectors; 331 unsigned int discard_granularity; 332 unsigned int discard_alignment; 333 334 unsigned short logical_block_size; 335 unsigned short max_segments; 336 unsigned short max_integrity_segments; 337 338 unsigned char misaligned; 339 unsigned char discard_misaligned; 340 unsigned char cluster; 341 unsigned char discard_zeroes_data; 342 unsigned char raid_partial_stripes_expensive; 343 enum blk_zoned_model zoned; 344 }; 345 346 #ifdef CONFIG_BLK_DEV_ZONED 347 348 struct blk_zone_report_hdr { 349 unsigned int nr_zones; 350 u8 padding[60]; 351 }; 352 353 extern int blkdev_report_zones(struct block_device *bdev, 354 sector_t sector, struct blk_zone *zones, 355 unsigned int *nr_zones, gfp_t gfp_mask); 356 extern int blkdev_reset_zones(struct block_device *bdev, sector_t sectors, 357 sector_t nr_sectors, gfp_t gfp_mask); 358 359 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode, 360 unsigned int cmd, unsigned long arg); 361 extern int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode, 362 unsigned int cmd, unsigned long arg); 363 364 #else /* CONFIG_BLK_DEV_ZONED */ 365 366 static inline int blkdev_report_zones_ioctl(struct block_device *bdev, 367 fmode_t mode, unsigned int cmd, 368 unsigned long arg) 369 { 370 return -ENOTTY; 371 } 372 373 static inline int blkdev_reset_zones_ioctl(struct block_device *bdev, 374 fmode_t mode, unsigned int cmd, 375 unsigned long arg) 376 { 377 return -ENOTTY; 378 } 379 380 #endif /* CONFIG_BLK_DEV_ZONED */ 381 382 struct request_queue { 383 /* 384 * Together with queue_head for cacheline sharing 385 */ 386 struct list_head queue_head; 387 struct request *last_merge; 388 struct elevator_queue *elevator; 389 int nr_rqs[2]; /* # allocated [a]sync rqs */ 390 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */ 391 392 struct rq_wb *rq_wb; 393 394 /* 395 * If blkcg is not used, @q->root_rl serves all requests. If blkcg 396 * is used, root blkg allocates from @q->root_rl and all other 397 * blkgs from their own blkg->rl. Which one to use should be 398 * determined using bio_request_list(). 399 */ 400 struct request_list root_rl; 401 402 request_fn_proc *request_fn; 403 make_request_fn *make_request_fn; 404 prep_rq_fn *prep_rq_fn; 405 unprep_rq_fn *unprep_rq_fn; 406 softirq_done_fn *softirq_done_fn; 407 rq_timed_out_fn *rq_timed_out_fn; 408 dma_drain_needed_fn *dma_drain_needed; 409 lld_busy_fn *lld_busy_fn; 410 411 struct blk_mq_ops *mq_ops; 412 413 unsigned int *mq_map; 414 415 /* sw queues */ 416 struct blk_mq_ctx __percpu *queue_ctx; 417 unsigned int nr_queues; 418 419 unsigned int queue_depth; 420 421 /* hw dispatch queues */ 422 struct blk_mq_hw_ctx **queue_hw_ctx; 423 unsigned int nr_hw_queues; 424 425 /* 426 * Dispatch queue sorting 427 */ 428 sector_t end_sector; 429 struct request *boundary_rq; 430 431 /* 432 * Delayed queue handling 433 */ 434 struct delayed_work delay_work; 435 436 struct backing_dev_info backing_dev_info; 437 438 /* 439 * The queue owner gets to use this for whatever they like. 440 * ll_rw_blk doesn't touch it. 441 */ 442 void *queuedata; 443 444 /* 445 * various queue flags, see QUEUE_* below 446 */ 447 unsigned long queue_flags; 448 449 /* 450 * ida allocated id for this queue. Used to index queues from 451 * ioctx. 452 */ 453 int id; 454 455 /* 456 * queue needs bounce pages for pages above this limit 457 */ 458 gfp_t bounce_gfp; 459 460 /* 461 * protects queue structures from reentrancy. ->__queue_lock should 462 * _never_ be used directly, it is queue private. always use 463 * ->queue_lock. 464 */ 465 spinlock_t __queue_lock; 466 spinlock_t *queue_lock; 467 468 /* 469 * queue kobject 470 */ 471 struct kobject kobj; 472 473 /* 474 * mq queue kobject 475 */ 476 struct kobject mq_kobj; 477 478 #ifdef CONFIG_BLK_DEV_INTEGRITY 479 struct blk_integrity integrity; 480 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 481 482 #ifdef CONFIG_PM 483 struct device *dev; 484 int rpm_status; 485 unsigned int nr_pending; 486 #endif 487 488 /* 489 * queue settings 490 */ 491 unsigned long nr_requests; /* Max # of requests */ 492 unsigned int nr_congestion_on; 493 unsigned int nr_congestion_off; 494 unsigned int nr_batching; 495 496 unsigned int dma_drain_size; 497 void *dma_drain_buffer; 498 unsigned int dma_pad_mask; 499 unsigned int dma_alignment; 500 501 struct blk_queue_tag *queue_tags; 502 struct list_head tag_busy_list; 503 504 unsigned int nr_sorted; 505 unsigned int in_flight[2]; 506 507 struct blk_rq_stat rq_stats[2]; 508 509 /* 510 * Number of active block driver functions for which blk_drain_queue() 511 * must wait. Must be incremented around functions that unlock the 512 * queue_lock internally, e.g. scsi_request_fn(). 513 */ 514 unsigned int request_fn_active; 515 516 unsigned int rq_timeout; 517 int poll_nsec; 518 struct timer_list timeout; 519 struct work_struct timeout_work; 520 struct list_head timeout_list; 521 522 struct list_head icq_list; 523 #ifdef CONFIG_BLK_CGROUP 524 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); 525 struct blkcg_gq *root_blkg; 526 struct list_head blkg_list; 527 #endif 528 529 struct queue_limits limits; 530 531 /* 532 * sg stuff 533 */ 534 unsigned int sg_timeout; 535 unsigned int sg_reserved_size; 536 int node; 537 #ifdef CONFIG_BLK_DEV_IO_TRACE 538 struct blk_trace *blk_trace; 539 #endif 540 /* 541 * for flush operations 542 */ 543 struct blk_flush_queue *fq; 544 545 struct list_head requeue_list; 546 spinlock_t requeue_lock; 547 struct delayed_work requeue_work; 548 549 struct mutex sysfs_lock; 550 551 int bypass_depth; 552 atomic_t mq_freeze_depth; 553 554 #if defined(CONFIG_BLK_DEV_BSG) 555 bsg_job_fn *bsg_job_fn; 556 int bsg_job_size; 557 struct bsg_class_device bsg_dev; 558 #endif 559 560 #ifdef CONFIG_BLK_DEV_THROTTLING 561 /* Throttle data */ 562 struct throtl_data *td; 563 #endif 564 struct rcu_head rcu_head; 565 wait_queue_head_t mq_freeze_wq; 566 struct percpu_ref q_usage_counter; 567 struct list_head all_q_node; 568 569 struct blk_mq_tag_set *tag_set; 570 struct list_head tag_set_list; 571 struct bio_set *bio_split; 572 573 bool mq_sysfs_init_done; 574 }; 575 576 #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ 577 #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ 578 #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ 579 #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ 580 #define QUEUE_FLAG_DYING 5 /* queue being torn down */ 581 #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */ 582 #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */ 583 #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */ 584 #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */ 585 #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */ 586 #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */ 587 #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */ 588 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 589 #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */ 590 #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */ 591 #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */ 592 #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */ 593 #define QUEUE_FLAG_SECERASE 17 /* supports secure erase */ 594 #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */ 595 #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */ 596 #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */ 597 #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/ 598 #define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */ 599 #define QUEUE_FLAG_WC 23 /* Write back caching */ 600 #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */ 601 #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */ 602 #define QUEUE_FLAG_DAX 26 /* device supports DAX */ 603 #define QUEUE_FLAG_STATS 27 /* track rq completion times */ 604 605 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 606 (1 << QUEUE_FLAG_STACKABLE) | \ 607 (1 << QUEUE_FLAG_SAME_COMP) | \ 608 (1 << QUEUE_FLAG_ADD_RANDOM)) 609 610 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 611 (1 << QUEUE_FLAG_STACKABLE) | \ 612 (1 << QUEUE_FLAG_SAME_COMP) | \ 613 (1 << QUEUE_FLAG_POLL)) 614 615 static inline void queue_lockdep_assert_held(struct request_queue *q) 616 { 617 if (q->queue_lock) 618 lockdep_assert_held(q->queue_lock); 619 } 620 621 static inline void queue_flag_set_unlocked(unsigned int flag, 622 struct request_queue *q) 623 { 624 __set_bit(flag, &q->queue_flags); 625 } 626 627 static inline int queue_flag_test_and_clear(unsigned int flag, 628 struct request_queue *q) 629 { 630 queue_lockdep_assert_held(q); 631 632 if (test_bit(flag, &q->queue_flags)) { 633 __clear_bit(flag, &q->queue_flags); 634 return 1; 635 } 636 637 return 0; 638 } 639 640 static inline int queue_flag_test_and_set(unsigned int flag, 641 struct request_queue *q) 642 { 643 queue_lockdep_assert_held(q); 644 645 if (!test_bit(flag, &q->queue_flags)) { 646 __set_bit(flag, &q->queue_flags); 647 return 0; 648 } 649 650 return 1; 651 } 652 653 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 654 { 655 queue_lockdep_assert_held(q); 656 __set_bit(flag, &q->queue_flags); 657 } 658 659 static inline void queue_flag_clear_unlocked(unsigned int flag, 660 struct request_queue *q) 661 { 662 __clear_bit(flag, &q->queue_flags); 663 } 664 665 static inline int queue_in_flight(struct request_queue *q) 666 { 667 return q->in_flight[0] + q->in_flight[1]; 668 } 669 670 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 671 { 672 queue_lockdep_assert_held(q); 673 __clear_bit(flag, &q->queue_flags); 674 } 675 676 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 677 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 678 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags) 679 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 680 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags) 681 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags) 682 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 683 #define blk_queue_noxmerges(q) \ 684 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 685 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 686 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 687 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 688 #define blk_queue_stackable(q) \ 689 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 690 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 691 #define blk_queue_secure_erase(q) \ 692 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags)) 693 #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags) 694 695 #define blk_noretry_request(rq) \ 696 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 697 REQ_FAILFAST_DRIVER)) 698 699 #define blk_account_rq(rq) \ 700 (((rq)->rq_flags & RQF_STARTED) && \ 701 ((rq)->cmd_type == REQ_TYPE_FS)) 702 703 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 704 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 705 /* rq->queuelist of dequeued request must be list_empty() */ 706 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 707 708 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 709 710 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ) 711 712 /* 713 * Driver can handle struct request, if it either has an old style 714 * request_fn defined, or is blk-mq based. 715 */ 716 static inline bool queue_is_rq_based(struct request_queue *q) 717 { 718 return q->request_fn || q->mq_ops; 719 } 720 721 static inline unsigned int blk_queue_cluster(struct request_queue *q) 722 { 723 return q->limits.cluster; 724 } 725 726 static inline enum blk_zoned_model 727 blk_queue_zoned_model(struct request_queue *q) 728 { 729 return q->limits.zoned; 730 } 731 732 static inline bool blk_queue_is_zoned(struct request_queue *q) 733 { 734 switch (blk_queue_zoned_model(q)) { 735 case BLK_ZONED_HA: 736 case BLK_ZONED_HM: 737 return true; 738 default: 739 return false; 740 } 741 } 742 743 static inline unsigned int blk_queue_zone_size(struct request_queue *q) 744 { 745 return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0; 746 } 747 748 static inline bool rq_is_sync(struct request *rq) 749 { 750 return op_is_sync(rq->cmd_flags); 751 } 752 753 static inline bool blk_rl_full(struct request_list *rl, bool sync) 754 { 755 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 756 757 return rl->flags & flag; 758 } 759 760 static inline void blk_set_rl_full(struct request_list *rl, bool sync) 761 { 762 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 763 764 rl->flags |= flag; 765 } 766 767 static inline void blk_clear_rl_full(struct request_list *rl, bool sync) 768 { 769 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 770 771 rl->flags &= ~flag; 772 } 773 774 static inline bool rq_mergeable(struct request *rq) 775 { 776 if (rq->cmd_type != REQ_TYPE_FS) 777 return false; 778 779 if (req_op(rq) == REQ_OP_FLUSH) 780 return false; 781 782 if (req_op(rq) == REQ_OP_WRITE_ZEROES) 783 return false; 784 785 if (rq->cmd_flags & REQ_NOMERGE_FLAGS) 786 return false; 787 if (rq->rq_flags & RQF_NOMERGE_FLAGS) 788 return false; 789 790 return true; 791 } 792 793 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b) 794 { 795 if (bio_data(a) == bio_data(b)) 796 return true; 797 798 return false; 799 } 800 801 static inline unsigned int blk_queue_depth(struct request_queue *q) 802 { 803 if (q->queue_depth) 804 return q->queue_depth; 805 806 return q->nr_requests; 807 } 808 809 /* 810 * q->prep_rq_fn return values 811 */ 812 enum { 813 BLKPREP_OK, /* serve it */ 814 BLKPREP_KILL, /* fatal error, kill, return -EIO */ 815 BLKPREP_DEFER, /* leave on queue */ 816 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */ 817 }; 818 819 extern unsigned long blk_max_low_pfn, blk_max_pfn; 820 821 /* 822 * standard bounce addresses: 823 * 824 * BLK_BOUNCE_HIGH : bounce all highmem pages 825 * BLK_BOUNCE_ANY : don't bounce anything 826 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 827 */ 828 829 #if BITS_PER_LONG == 32 830 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 831 #else 832 #define BLK_BOUNCE_HIGH -1ULL 833 #endif 834 #define BLK_BOUNCE_ANY (-1ULL) 835 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 836 837 /* 838 * default timeout for SG_IO if none specified 839 */ 840 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 841 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 842 843 #ifdef CONFIG_BOUNCE 844 extern int init_emergency_isa_pool(void); 845 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 846 #else 847 static inline int init_emergency_isa_pool(void) 848 { 849 return 0; 850 } 851 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 852 { 853 } 854 #endif /* CONFIG_MMU */ 855 856 struct rq_map_data { 857 struct page **pages; 858 int page_order; 859 int nr_entries; 860 unsigned long offset; 861 int null_mapped; 862 int from_user; 863 }; 864 865 struct req_iterator { 866 struct bvec_iter iter; 867 struct bio *bio; 868 }; 869 870 /* This should not be used directly - use rq_for_each_segment */ 871 #define for_each_bio(_bio) \ 872 for (; _bio; _bio = _bio->bi_next) 873 #define __rq_for_each_bio(_bio, rq) \ 874 if ((rq->bio)) \ 875 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 876 877 #define rq_for_each_segment(bvl, _rq, _iter) \ 878 __rq_for_each_bio(_iter.bio, _rq) \ 879 bio_for_each_segment(bvl, _iter.bio, _iter.iter) 880 881 #define rq_iter_last(bvec, _iter) \ 882 (_iter.bio->bi_next == NULL && \ 883 bio_iter_last(bvec, _iter.iter)) 884 885 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 886 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 887 #endif 888 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 889 extern void rq_flush_dcache_pages(struct request *rq); 890 #else 891 static inline void rq_flush_dcache_pages(struct request *rq) 892 { 893 } 894 #endif 895 896 #ifdef CONFIG_PRINTK 897 #define vfs_msg(sb, level, fmt, ...) \ 898 __vfs_msg(sb, level, fmt, ##__VA_ARGS__) 899 #else 900 #define vfs_msg(sb, level, fmt, ...) \ 901 do { \ 902 no_printk(fmt, ##__VA_ARGS__); \ 903 __vfs_msg(sb, "", " "); \ 904 } while (0) 905 #endif 906 907 extern int blk_register_queue(struct gendisk *disk); 908 extern void blk_unregister_queue(struct gendisk *disk); 909 extern blk_qc_t generic_make_request(struct bio *bio); 910 extern void blk_rq_init(struct request_queue *q, struct request *rq); 911 extern void blk_put_request(struct request *); 912 extern void __blk_put_request(struct request_queue *, struct request *); 913 extern struct request *blk_get_request(struct request_queue *, int, gfp_t); 914 extern void blk_rq_set_block_pc(struct request *); 915 extern void blk_requeue_request(struct request_queue *, struct request *); 916 extern int blk_lld_busy(struct request_queue *q); 917 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 918 struct bio_set *bs, gfp_t gfp_mask, 919 int (*bio_ctr)(struct bio *, struct bio *, void *), 920 void *data); 921 extern void blk_rq_unprep_clone(struct request *rq); 922 extern int blk_insert_cloned_request(struct request_queue *q, 923 struct request *rq); 924 extern int blk_rq_append_bio(struct request *rq, struct bio *bio); 925 extern void blk_delay_queue(struct request_queue *, unsigned long); 926 extern void blk_queue_split(struct request_queue *, struct bio **, 927 struct bio_set *); 928 extern void blk_recount_segments(struct request_queue *, struct bio *); 929 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 930 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 931 unsigned int, void __user *); 932 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 933 unsigned int, void __user *); 934 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 935 struct scsi_ioctl_command __user *); 936 937 extern int blk_queue_enter(struct request_queue *q, bool nowait); 938 extern void blk_queue_exit(struct request_queue *q); 939 extern void blk_start_queue(struct request_queue *q); 940 extern void blk_start_queue_async(struct request_queue *q); 941 extern void blk_stop_queue(struct request_queue *q); 942 extern void blk_sync_queue(struct request_queue *q); 943 extern void __blk_stop_queue(struct request_queue *q); 944 extern void __blk_run_queue(struct request_queue *q); 945 extern void __blk_run_queue_uncond(struct request_queue *q); 946 extern void blk_run_queue(struct request_queue *); 947 extern void blk_run_queue_async(struct request_queue *q); 948 extern void blk_mq_quiesce_queue(struct request_queue *q); 949 extern int blk_rq_map_user(struct request_queue *, struct request *, 950 struct rq_map_data *, void __user *, unsigned long, 951 gfp_t); 952 extern int blk_rq_unmap_user(struct bio *); 953 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 954 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 955 struct rq_map_data *, const struct iov_iter *, 956 gfp_t); 957 extern int blk_execute_rq(struct request_queue *, struct gendisk *, 958 struct request *, int); 959 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 960 struct request *, int, rq_end_io_fn *); 961 962 bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie); 963 964 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 965 { 966 return bdev->bd_disk->queue; /* this is never NULL */ 967 } 968 969 /* 970 * blk_rq_pos() : the current sector 971 * blk_rq_bytes() : bytes left in the entire request 972 * blk_rq_cur_bytes() : bytes left in the current segment 973 * blk_rq_err_bytes() : bytes left till the next error boundary 974 * blk_rq_sectors() : sectors left in the entire request 975 * blk_rq_cur_sectors() : sectors left in the current segment 976 */ 977 static inline sector_t blk_rq_pos(const struct request *rq) 978 { 979 return rq->__sector; 980 } 981 982 static inline unsigned int blk_rq_bytes(const struct request *rq) 983 { 984 return rq->__data_len; 985 } 986 987 static inline int blk_rq_cur_bytes(const struct request *rq) 988 { 989 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 990 } 991 992 extern unsigned int blk_rq_err_bytes(const struct request *rq); 993 994 static inline unsigned int blk_rq_sectors(const struct request *rq) 995 { 996 return blk_rq_bytes(rq) >> 9; 997 } 998 999 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 1000 { 1001 return blk_rq_cur_bytes(rq) >> 9; 1002 } 1003 1004 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q, 1005 int op) 1006 { 1007 if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE)) 1008 return min(q->limits.max_discard_sectors, UINT_MAX >> 9); 1009 1010 if (unlikely(op == REQ_OP_WRITE_SAME)) 1011 return q->limits.max_write_same_sectors; 1012 1013 if (unlikely(op == REQ_OP_WRITE_ZEROES)) 1014 return q->limits.max_write_zeroes_sectors; 1015 1016 return q->limits.max_sectors; 1017 } 1018 1019 /* 1020 * Return maximum size of a request at given offset. Only valid for 1021 * file system requests. 1022 */ 1023 static inline unsigned int blk_max_size_offset(struct request_queue *q, 1024 sector_t offset) 1025 { 1026 if (!q->limits.chunk_sectors) 1027 return q->limits.max_sectors; 1028 1029 return q->limits.chunk_sectors - 1030 (offset & (q->limits.chunk_sectors - 1)); 1031 } 1032 1033 static inline unsigned int blk_rq_get_max_sectors(struct request *rq, 1034 sector_t offset) 1035 { 1036 struct request_queue *q = rq->q; 1037 1038 if (unlikely(rq->cmd_type != REQ_TYPE_FS)) 1039 return q->limits.max_hw_sectors; 1040 1041 if (!q->limits.chunk_sectors || 1042 req_op(rq) == REQ_OP_DISCARD || 1043 req_op(rq) == REQ_OP_SECURE_ERASE) 1044 return blk_queue_get_max_sectors(q, req_op(rq)); 1045 1046 return min(blk_max_size_offset(q, offset), 1047 blk_queue_get_max_sectors(q, req_op(rq))); 1048 } 1049 1050 static inline unsigned int blk_rq_count_bios(struct request *rq) 1051 { 1052 unsigned int nr_bios = 0; 1053 struct bio *bio; 1054 1055 __rq_for_each_bio(bio, rq) 1056 nr_bios++; 1057 1058 return nr_bios; 1059 } 1060 1061 /* 1062 * blk_rq_set_prio - associate a request with prio from ioc 1063 * @rq: request of interest 1064 * @ioc: target iocontext 1065 * 1066 * Assocate request prio with ioc prio so request based drivers 1067 * can leverage priority information. 1068 */ 1069 static inline void blk_rq_set_prio(struct request *rq, struct io_context *ioc) 1070 { 1071 if (ioc) 1072 rq->ioprio = ioc->ioprio; 1073 } 1074 1075 /* 1076 * Request issue related functions. 1077 */ 1078 extern struct request *blk_peek_request(struct request_queue *q); 1079 extern void blk_start_request(struct request *rq); 1080 extern struct request *blk_fetch_request(struct request_queue *q); 1081 1082 /* 1083 * Request completion related functions. 1084 * 1085 * blk_update_request() completes given number of bytes and updates 1086 * the request without completing it. 1087 * 1088 * blk_end_request() and friends. __blk_end_request() must be called 1089 * with the request queue spinlock acquired. 1090 * 1091 * Several drivers define their own end_request and call 1092 * blk_end_request() for parts of the original function. 1093 * This prevents code duplication in drivers. 1094 */ 1095 extern bool blk_update_request(struct request *rq, int error, 1096 unsigned int nr_bytes); 1097 extern void blk_finish_request(struct request *rq, int error); 1098 extern bool blk_end_request(struct request *rq, int error, 1099 unsigned int nr_bytes); 1100 extern void blk_end_request_all(struct request *rq, int error); 1101 extern bool blk_end_request_cur(struct request *rq, int error); 1102 extern bool blk_end_request_err(struct request *rq, int error); 1103 extern bool __blk_end_request(struct request *rq, int error, 1104 unsigned int nr_bytes); 1105 extern void __blk_end_request_all(struct request *rq, int error); 1106 extern bool __blk_end_request_cur(struct request *rq, int error); 1107 extern bool __blk_end_request_err(struct request *rq, int error); 1108 1109 extern void blk_complete_request(struct request *); 1110 extern void __blk_complete_request(struct request *); 1111 extern void blk_abort_request(struct request *); 1112 extern void blk_unprep_request(struct request *); 1113 1114 /* 1115 * Access functions for manipulating queue properties 1116 */ 1117 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 1118 spinlock_t *lock, int node_id); 1119 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 1120 extern struct request_queue *blk_init_allocated_queue(struct request_queue *, 1121 request_fn_proc *, spinlock_t *); 1122 extern void blk_cleanup_queue(struct request_queue *); 1123 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 1124 extern void blk_queue_bounce_limit(struct request_queue *, u64); 1125 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 1126 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int); 1127 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 1128 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 1129 extern void blk_queue_max_discard_sectors(struct request_queue *q, 1130 unsigned int max_discard_sectors); 1131 extern void blk_queue_max_write_same_sectors(struct request_queue *q, 1132 unsigned int max_write_same_sectors); 1133 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q, 1134 unsigned int max_write_same_sectors); 1135 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 1136 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 1137 extern void blk_queue_alignment_offset(struct request_queue *q, 1138 unsigned int alignment); 1139 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 1140 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 1141 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 1142 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 1143 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth); 1144 extern void blk_set_default_limits(struct queue_limits *lim); 1145 extern void blk_set_stacking_limits(struct queue_limits *lim); 1146 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 1147 sector_t offset); 1148 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 1149 sector_t offset); 1150 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 1151 sector_t offset); 1152 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 1153 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 1154 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 1155 extern int blk_queue_dma_drain(struct request_queue *q, 1156 dma_drain_needed_fn *dma_drain_needed, 1157 void *buf, unsigned int size); 1158 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 1159 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 1160 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long); 1161 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 1162 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 1163 extern void blk_queue_dma_alignment(struct request_queue *, int); 1164 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 1165 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 1166 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 1167 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 1168 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 1169 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua); 1170 extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); 1171 1172 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq) 1173 { 1174 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD) 1175 return 1; 1176 return rq->nr_phys_segments; 1177 } 1178 1179 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 1180 extern void blk_dump_rq_flags(struct request *, char *); 1181 extern long nr_blockdev_pages(void); 1182 1183 bool __must_check blk_get_queue(struct request_queue *); 1184 struct request_queue *blk_alloc_queue(gfp_t); 1185 struct request_queue *blk_alloc_queue_node(gfp_t, int); 1186 extern void blk_put_queue(struct request_queue *); 1187 extern void blk_set_queue_dying(struct request_queue *); 1188 1189 /* 1190 * block layer runtime pm functions 1191 */ 1192 #ifdef CONFIG_PM 1193 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev); 1194 extern int blk_pre_runtime_suspend(struct request_queue *q); 1195 extern void blk_post_runtime_suspend(struct request_queue *q, int err); 1196 extern void blk_pre_runtime_resume(struct request_queue *q); 1197 extern void blk_post_runtime_resume(struct request_queue *q, int err); 1198 extern void blk_set_runtime_active(struct request_queue *q); 1199 #else 1200 static inline void blk_pm_runtime_init(struct request_queue *q, 1201 struct device *dev) {} 1202 static inline int blk_pre_runtime_suspend(struct request_queue *q) 1203 { 1204 return -ENOSYS; 1205 } 1206 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {} 1207 static inline void blk_pre_runtime_resume(struct request_queue *q) {} 1208 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {} 1209 static inline void blk_set_runtime_active(struct request_queue *q) {} 1210 #endif 1211 1212 /* 1213 * blk_plug permits building a queue of related requests by holding the I/O 1214 * fragments for a short period. This allows merging of sequential requests 1215 * into single larger request. As the requests are moved from a per-task list to 1216 * the device's request_queue in a batch, this results in improved scalability 1217 * as the lock contention for request_queue lock is reduced. 1218 * 1219 * It is ok not to disable preemption when adding the request to the plug list 1220 * or when attempting a merge, because blk_schedule_flush_list() will only flush 1221 * the plug list when the task sleeps by itself. For details, please see 1222 * schedule() where blk_schedule_flush_plug() is called. 1223 */ 1224 struct blk_plug { 1225 struct list_head list; /* requests */ 1226 struct list_head mq_list; /* blk-mq requests */ 1227 struct list_head cb_list; /* md requires an unplug callback */ 1228 }; 1229 #define BLK_MAX_REQUEST_COUNT 16 1230 #define BLK_PLUG_FLUSH_SIZE (128 * 1024) 1231 1232 struct blk_plug_cb; 1233 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool); 1234 struct blk_plug_cb { 1235 struct list_head list; 1236 blk_plug_cb_fn callback; 1237 void *data; 1238 }; 1239 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, 1240 void *data, int size); 1241 extern void blk_start_plug(struct blk_plug *); 1242 extern void blk_finish_plug(struct blk_plug *); 1243 extern void blk_flush_plug_list(struct blk_plug *, bool); 1244 1245 static inline void blk_flush_plug(struct task_struct *tsk) 1246 { 1247 struct blk_plug *plug = tsk->plug; 1248 1249 if (plug) 1250 blk_flush_plug_list(plug, false); 1251 } 1252 1253 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 1254 { 1255 struct blk_plug *plug = tsk->plug; 1256 1257 if (plug) 1258 blk_flush_plug_list(plug, true); 1259 } 1260 1261 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1262 { 1263 struct blk_plug *plug = tsk->plug; 1264 1265 return plug && 1266 (!list_empty(&plug->list) || 1267 !list_empty(&plug->mq_list) || 1268 !list_empty(&plug->cb_list)); 1269 } 1270 1271 /* 1272 * tag stuff 1273 */ 1274 extern int blk_queue_start_tag(struct request_queue *, struct request *); 1275 extern struct request *blk_queue_find_tag(struct request_queue *, int); 1276 extern void blk_queue_end_tag(struct request_queue *, struct request *); 1277 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int); 1278 extern void blk_queue_free_tags(struct request_queue *); 1279 extern int blk_queue_resize_tags(struct request_queue *, int); 1280 extern void blk_queue_invalidate_tags(struct request_queue *); 1281 extern struct blk_queue_tag *blk_init_tags(int, int); 1282 extern void blk_free_tags(struct blk_queue_tag *); 1283 1284 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 1285 int tag) 1286 { 1287 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 1288 return NULL; 1289 return bqt->tag_index[tag]; 1290 } 1291 1292 1293 #define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */ 1294 #define BLKDEV_DISCARD_ZERO (1 << 1) /* must reliably zero data */ 1295 1296 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 1297 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1298 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 1299 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1300 sector_t nr_sects, gfp_t gfp_mask, int flags, 1301 struct bio **biop); 1302 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, 1303 sector_t nr_sects, gfp_t gfp_mask, struct page *page); 1304 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1305 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop, 1306 bool discard); 1307 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1308 sector_t nr_sects, gfp_t gfp_mask, bool discard); 1309 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 1310 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 1311 { 1312 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 1313 nr_blocks << (sb->s_blocksize_bits - 9), 1314 gfp_mask, flags); 1315 } 1316 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 1317 sector_t nr_blocks, gfp_t gfp_mask) 1318 { 1319 return blkdev_issue_zeroout(sb->s_bdev, 1320 block << (sb->s_blocksize_bits - 9), 1321 nr_blocks << (sb->s_blocksize_bits - 9), 1322 gfp_mask, true); 1323 } 1324 1325 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 1326 1327 enum blk_default_limits { 1328 BLK_MAX_SEGMENTS = 128, 1329 BLK_SAFE_MAX_SECTORS = 255, 1330 BLK_DEF_MAX_SECTORS = 2560, 1331 BLK_MAX_SEGMENT_SIZE = 65536, 1332 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 1333 }; 1334 1335 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1336 1337 static inline unsigned long queue_bounce_pfn(struct request_queue *q) 1338 { 1339 return q->limits.bounce_pfn; 1340 } 1341 1342 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1343 { 1344 return q->limits.seg_boundary_mask; 1345 } 1346 1347 static inline unsigned long queue_virt_boundary(struct request_queue *q) 1348 { 1349 return q->limits.virt_boundary_mask; 1350 } 1351 1352 static inline unsigned int queue_max_sectors(struct request_queue *q) 1353 { 1354 return q->limits.max_sectors; 1355 } 1356 1357 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1358 { 1359 return q->limits.max_hw_sectors; 1360 } 1361 1362 static inline unsigned short queue_max_segments(struct request_queue *q) 1363 { 1364 return q->limits.max_segments; 1365 } 1366 1367 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1368 { 1369 return q->limits.max_segment_size; 1370 } 1371 1372 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1373 { 1374 int retval = 512; 1375 1376 if (q && q->limits.logical_block_size) 1377 retval = q->limits.logical_block_size; 1378 1379 return retval; 1380 } 1381 1382 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1383 { 1384 return queue_logical_block_size(bdev_get_queue(bdev)); 1385 } 1386 1387 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1388 { 1389 return q->limits.physical_block_size; 1390 } 1391 1392 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1393 { 1394 return queue_physical_block_size(bdev_get_queue(bdev)); 1395 } 1396 1397 static inline unsigned int queue_io_min(struct request_queue *q) 1398 { 1399 return q->limits.io_min; 1400 } 1401 1402 static inline int bdev_io_min(struct block_device *bdev) 1403 { 1404 return queue_io_min(bdev_get_queue(bdev)); 1405 } 1406 1407 static inline unsigned int queue_io_opt(struct request_queue *q) 1408 { 1409 return q->limits.io_opt; 1410 } 1411 1412 static inline int bdev_io_opt(struct block_device *bdev) 1413 { 1414 return queue_io_opt(bdev_get_queue(bdev)); 1415 } 1416 1417 static inline int queue_alignment_offset(struct request_queue *q) 1418 { 1419 if (q->limits.misaligned) 1420 return -1; 1421 1422 return q->limits.alignment_offset; 1423 } 1424 1425 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1426 { 1427 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1428 unsigned int alignment = sector_div(sector, granularity >> 9) << 9; 1429 1430 return (granularity + lim->alignment_offset - alignment) % granularity; 1431 } 1432 1433 static inline int bdev_alignment_offset(struct block_device *bdev) 1434 { 1435 struct request_queue *q = bdev_get_queue(bdev); 1436 1437 if (q->limits.misaligned) 1438 return -1; 1439 1440 if (bdev != bdev->bd_contains) 1441 return bdev->bd_part->alignment_offset; 1442 1443 return q->limits.alignment_offset; 1444 } 1445 1446 static inline int queue_discard_alignment(struct request_queue *q) 1447 { 1448 if (q->limits.discard_misaligned) 1449 return -1; 1450 1451 return q->limits.discard_alignment; 1452 } 1453 1454 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1455 { 1456 unsigned int alignment, granularity, offset; 1457 1458 if (!lim->max_discard_sectors) 1459 return 0; 1460 1461 /* Why are these in bytes, not sectors? */ 1462 alignment = lim->discard_alignment >> 9; 1463 granularity = lim->discard_granularity >> 9; 1464 if (!granularity) 1465 return 0; 1466 1467 /* Offset of the partition start in 'granularity' sectors */ 1468 offset = sector_div(sector, granularity); 1469 1470 /* And why do we do this modulus *again* in blkdev_issue_discard()? */ 1471 offset = (granularity + alignment - offset) % granularity; 1472 1473 /* Turn it back into bytes, gaah */ 1474 return offset << 9; 1475 } 1476 1477 static inline int bdev_discard_alignment(struct block_device *bdev) 1478 { 1479 struct request_queue *q = bdev_get_queue(bdev); 1480 1481 if (bdev != bdev->bd_contains) 1482 return bdev->bd_part->discard_alignment; 1483 1484 return q->limits.discard_alignment; 1485 } 1486 1487 static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) 1488 { 1489 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) 1490 return 1; 1491 1492 return 0; 1493 } 1494 1495 static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) 1496 { 1497 return queue_discard_zeroes_data(bdev_get_queue(bdev)); 1498 } 1499 1500 static inline unsigned int bdev_write_same(struct block_device *bdev) 1501 { 1502 struct request_queue *q = bdev_get_queue(bdev); 1503 1504 if (q) 1505 return q->limits.max_write_same_sectors; 1506 1507 return 0; 1508 } 1509 1510 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev) 1511 { 1512 struct request_queue *q = bdev_get_queue(bdev); 1513 1514 if (q) 1515 return q->limits.max_write_zeroes_sectors; 1516 1517 return 0; 1518 } 1519 1520 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev) 1521 { 1522 struct request_queue *q = bdev_get_queue(bdev); 1523 1524 if (q) 1525 return blk_queue_zoned_model(q); 1526 1527 return BLK_ZONED_NONE; 1528 } 1529 1530 static inline bool bdev_is_zoned(struct block_device *bdev) 1531 { 1532 struct request_queue *q = bdev_get_queue(bdev); 1533 1534 if (q) 1535 return blk_queue_is_zoned(q); 1536 1537 return false; 1538 } 1539 1540 static inline unsigned int bdev_zone_size(struct block_device *bdev) 1541 { 1542 struct request_queue *q = bdev_get_queue(bdev); 1543 1544 if (q) 1545 return blk_queue_zone_size(q); 1546 1547 return 0; 1548 } 1549 1550 static inline int queue_dma_alignment(struct request_queue *q) 1551 { 1552 return q ? q->dma_alignment : 511; 1553 } 1554 1555 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1556 unsigned int len) 1557 { 1558 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1559 return !(addr & alignment) && !(len & alignment); 1560 } 1561 1562 /* assumes size > 256 */ 1563 static inline unsigned int blksize_bits(unsigned int size) 1564 { 1565 unsigned int bits = 8; 1566 do { 1567 bits++; 1568 size >>= 1; 1569 } while (size > 256); 1570 return bits; 1571 } 1572 1573 static inline unsigned int block_size(struct block_device *bdev) 1574 { 1575 return bdev->bd_block_size; 1576 } 1577 1578 static inline bool queue_flush_queueable(struct request_queue *q) 1579 { 1580 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags); 1581 } 1582 1583 typedef struct {struct page *v;} Sector; 1584 1585 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1586 1587 static inline void put_dev_sector(Sector p) 1588 { 1589 put_page(p.v); 1590 } 1591 1592 static inline bool __bvec_gap_to_prev(struct request_queue *q, 1593 struct bio_vec *bprv, unsigned int offset) 1594 { 1595 return offset || 1596 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); 1597 } 1598 1599 /* 1600 * Check if adding a bio_vec after bprv with offset would create a gap in 1601 * the SG list. Most drivers don't care about this, but some do. 1602 */ 1603 static inline bool bvec_gap_to_prev(struct request_queue *q, 1604 struct bio_vec *bprv, unsigned int offset) 1605 { 1606 if (!queue_virt_boundary(q)) 1607 return false; 1608 return __bvec_gap_to_prev(q, bprv, offset); 1609 } 1610 1611 static inline bool bio_will_gap(struct request_queue *q, struct bio *prev, 1612 struct bio *next) 1613 { 1614 if (bio_has_data(prev) && queue_virt_boundary(q)) { 1615 struct bio_vec pb, nb; 1616 1617 bio_get_last_bvec(prev, &pb); 1618 bio_get_first_bvec(next, &nb); 1619 1620 return __bvec_gap_to_prev(q, &pb, nb.bv_offset); 1621 } 1622 1623 return false; 1624 } 1625 1626 static inline bool req_gap_back_merge(struct request *req, struct bio *bio) 1627 { 1628 return bio_will_gap(req->q, req->biotail, bio); 1629 } 1630 1631 static inline bool req_gap_front_merge(struct request *req, struct bio *bio) 1632 { 1633 return bio_will_gap(req->q, bio, req->bio); 1634 } 1635 1636 int kblockd_schedule_work(struct work_struct *work); 1637 int kblockd_schedule_work_on(int cpu, struct work_struct *work); 1638 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay); 1639 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay); 1640 1641 #ifdef CONFIG_BLK_CGROUP 1642 /* 1643 * This should not be using sched_clock(). A real patch is in progress 1644 * to fix this up, until that is in place we need to disable preemption 1645 * around sched_clock() in this function and set_io_start_time_ns(). 1646 */ 1647 static inline void set_start_time_ns(struct request *req) 1648 { 1649 preempt_disable(); 1650 req->start_time_ns = sched_clock(); 1651 preempt_enable(); 1652 } 1653 1654 static inline void set_io_start_time_ns(struct request *req) 1655 { 1656 preempt_disable(); 1657 req->io_start_time_ns = sched_clock(); 1658 preempt_enable(); 1659 } 1660 1661 static inline uint64_t rq_start_time_ns(struct request *req) 1662 { 1663 return req->start_time_ns; 1664 } 1665 1666 static inline uint64_t rq_io_start_time_ns(struct request *req) 1667 { 1668 return req->io_start_time_ns; 1669 } 1670 #else 1671 static inline void set_start_time_ns(struct request *req) {} 1672 static inline void set_io_start_time_ns(struct request *req) {} 1673 static inline uint64_t rq_start_time_ns(struct request *req) 1674 { 1675 return 0; 1676 } 1677 static inline uint64_t rq_io_start_time_ns(struct request *req) 1678 { 1679 return 0; 1680 } 1681 #endif 1682 1683 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1684 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1685 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1686 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1687 1688 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1689 1690 enum blk_integrity_flags { 1691 BLK_INTEGRITY_VERIFY = 1 << 0, 1692 BLK_INTEGRITY_GENERATE = 1 << 1, 1693 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2, 1694 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3, 1695 }; 1696 1697 struct blk_integrity_iter { 1698 void *prot_buf; 1699 void *data_buf; 1700 sector_t seed; 1701 unsigned int data_size; 1702 unsigned short interval; 1703 const char *disk_name; 1704 }; 1705 1706 typedef int (integrity_processing_fn) (struct blk_integrity_iter *); 1707 1708 struct blk_integrity_profile { 1709 integrity_processing_fn *generate_fn; 1710 integrity_processing_fn *verify_fn; 1711 const char *name; 1712 }; 1713 1714 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *); 1715 extern void blk_integrity_unregister(struct gendisk *); 1716 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1717 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1718 struct scatterlist *); 1719 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1720 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, 1721 struct request *); 1722 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, 1723 struct bio *); 1724 1725 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1726 { 1727 struct blk_integrity *bi = &disk->queue->integrity; 1728 1729 if (!bi->profile) 1730 return NULL; 1731 1732 return bi; 1733 } 1734 1735 static inline 1736 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1737 { 1738 return blk_get_integrity(bdev->bd_disk); 1739 } 1740 1741 static inline bool blk_integrity_rq(struct request *rq) 1742 { 1743 return rq->cmd_flags & REQ_INTEGRITY; 1744 } 1745 1746 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1747 unsigned int segs) 1748 { 1749 q->limits.max_integrity_segments = segs; 1750 } 1751 1752 static inline unsigned short 1753 queue_max_integrity_segments(struct request_queue *q) 1754 { 1755 return q->limits.max_integrity_segments; 1756 } 1757 1758 static inline bool integrity_req_gap_back_merge(struct request *req, 1759 struct bio *next) 1760 { 1761 struct bio_integrity_payload *bip = bio_integrity(req->bio); 1762 struct bio_integrity_payload *bip_next = bio_integrity(next); 1763 1764 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1765 bip_next->bip_vec[0].bv_offset); 1766 } 1767 1768 static inline bool integrity_req_gap_front_merge(struct request *req, 1769 struct bio *bio) 1770 { 1771 struct bio_integrity_payload *bip = bio_integrity(bio); 1772 struct bio_integrity_payload *bip_next = bio_integrity(req->bio); 1773 1774 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1775 bip_next->bip_vec[0].bv_offset); 1776 } 1777 1778 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1779 1780 struct bio; 1781 struct block_device; 1782 struct gendisk; 1783 struct blk_integrity; 1784 1785 static inline int blk_integrity_rq(struct request *rq) 1786 { 1787 return 0; 1788 } 1789 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1790 struct bio *b) 1791 { 1792 return 0; 1793 } 1794 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1795 struct bio *b, 1796 struct scatterlist *s) 1797 { 1798 return 0; 1799 } 1800 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1801 { 1802 return NULL; 1803 } 1804 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1805 { 1806 return NULL; 1807 } 1808 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1809 { 1810 return 0; 1811 } 1812 static inline void blk_integrity_register(struct gendisk *d, 1813 struct blk_integrity *b) 1814 { 1815 } 1816 static inline void blk_integrity_unregister(struct gendisk *d) 1817 { 1818 } 1819 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1820 unsigned int segs) 1821 { 1822 } 1823 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1824 { 1825 return 0; 1826 } 1827 static inline bool blk_integrity_merge_rq(struct request_queue *rq, 1828 struct request *r1, 1829 struct request *r2) 1830 { 1831 return true; 1832 } 1833 static inline bool blk_integrity_merge_bio(struct request_queue *rq, 1834 struct request *r, 1835 struct bio *b) 1836 { 1837 return true; 1838 } 1839 1840 static inline bool integrity_req_gap_back_merge(struct request *req, 1841 struct bio *next) 1842 { 1843 return false; 1844 } 1845 static inline bool integrity_req_gap_front_merge(struct request *req, 1846 struct bio *bio) 1847 { 1848 return false; 1849 } 1850 1851 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1852 1853 /** 1854 * struct blk_dax_ctl - control and output parameters for ->direct_access 1855 * @sector: (input) offset relative to a block_device 1856 * @addr: (output) kernel virtual address for @sector populated by driver 1857 * @pfn: (output) page frame number for @addr populated by driver 1858 * @size: (input) number of bytes requested 1859 */ 1860 struct blk_dax_ctl { 1861 sector_t sector; 1862 void *addr; 1863 long size; 1864 pfn_t pfn; 1865 }; 1866 1867 struct block_device_operations { 1868 int (*open) (struct block_device *, fmode_t); 1869 void (*release) (struct gendisk *, fmode_t); 1870 int (*rw_page)(struct block_device *, sector_t, struct page *, bool); 1871 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1872 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1873 long (*direct_access)(struct block_device *, sector_t, void **, pfn_t *, 1874 long); 1875 unsigned int (*check_events) (struct gendisk *disk, 1876 unsigned int clearing); 1877 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1878 int (*media_changed) (struct gendisk *); 1879 void (*unlock_native_capacity) (struct gendisk *); 1880 int (*revalidate_disk) (struct gendisk *); 1881 int (*getgeo)(struct block_device *, struct hd_geometry *); 1882 /* this callback is with swap_lock and sometimes page table lock held */ 1883 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1884 struct module *owner; 1885 const struct pr_ops *pr_ops; 1886 }; 1887 1888 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1889 unsigned long); 1890 extern int bdev_read_page(struct block_device *, sector_t, struct page *); 1891 extern int bdev_write_page(struct block_device *, sector_t, struct page *, 1892 struct writeback_control *); 1893 extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *); 1894 extern int bdev_dax_supported(struct super_block *, int); 1895 extern bool bdev_dax_capable(struct block_device *); 1896 #else /* CONFIG_BLOCK */ 1897 1898 struct block_device; 1899 1900 /* 1901 * stubs for when the block layer is configured out 1902 */ 1903 #define buffer_heads_over_limit 0 1904 1905 static inline long nr_blockdev_pages(void) 1906 { 1907 return 0; 1908 } 1909 1910 struct blk_plug { 1911 }; 1912 1913 static inline void blk_start_plug(struct blk_plug *plug) 1914 { 1915 } 1916 1917 static inline void blk_finish_plug(struct blk_plug *plug) 1918 { 1919 } 1920 1921 static inline void blk_flush_plug(struct task_struct *task) 1922 { 1923 } 1924 1925 static inline void blk_schedule_flush_plug(struct task_struct *task) 1926 { 1927 } 1928 1929 1930 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1931 { 1932 return false; 1933 } 1934 1935 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, 1936 sector_t *error_sector) 1937 { 1938 return 0; 1939 } 1940 1941 #endif /* CONFIG_BLOCK */ 1942 1943 #endif 1944