1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_BLKDEV_H 3 #define _LINUX_BLKDEV_H 4 5 #include <linux/sched.h> 6 #include <linux/sched/clock.h> 7 8 #ifdef CONFIG_BLOCK 9 10 #include <linux/major.h> 11 #include <linux/genhd.h> 12 #include <linux/list.h> 13 #include <linux/llist.h> 14 #include <linux/timer.h> 15 #include <linux/workqueue.h> 16 #include <linux/pagemap.h> 17 #include <linux/backing-dev-defs.h> 18 #include <linux/wait.h> 19 #include <linux/mempool.h> 20 #include <linux/pfn.h> 21 #include <linux/bio.h> 22 #include <linux/stringify.h> 23 #include <linux/gfp.h> 24 #include <linux/bsg.h> 25 #include <linux/smp.h> 26 #include <linux/rcupdate.h> 27 #include <linux/percpu-refcount.h> 28 #include <linux/scatterlist.h> 29 #include <linux/blkzoned.h> 30 31 struct module; 32 struct scsi_ioctl_command; 33 34 struct request_queue; 35 struct elevator_queue; 36 struct blk_trace; 37 struct request; 38 struct sg_io_hdr; 39 struct bsg_job; 40 struct blkcg_gq; 41 struct blk_flush_queue; 42 struct pr_ops; 43 struct rq_wb; 44 struct blk_queue_stats; 45 struct blk_stat_callback; 46 47 #define BLKDEV_MIN_RQ 4 48 #define BLKDEV_MAX_RQ 128 /* Default maximum */ 49 50 /* Must be consisitent with blk_mq_poll_stats_bkt() */ 51 #define BLK_MQ_POLL_STATS_BKTS 16 52 53 /* 54 * Maximum number of blkcg policies allowed to be registered concurrently. 55 * Defined here to simplify include dependency. 56 */ 57 #define BLKCG_MAX_POLS 3 58 59 typedef void (rq_end_io_fn)(struct request *, blk_status_t); 60 61 #define BLK_RL_SYNCFULL (1U << 0) 62 #define BLK_RL_ASYNCFULL (1U << 1) 63 64 struct request_list { 65 struct request_queue *q; /* the queue this rl belongs to */ 66 #ifdef CONFIG_BLK_CGROUP 67 struct blkcg_gq *blkg; /* blkg this request pool belongs to */ 68 #endif 69 /* 70 * count[], starved[], and wait[] are indexed by 71 * BLK_RW_SYNC/BLK_RW_ASYNC 72 */ 73 int count[2]; 74 int starved[2]; 75 mempool_t *rq_pool; 76 wait_queue_head_t wait[2]; 77 unsigned int flags; 78 }; 79 80 /* 81 * request flags */ 82 typedef __u32 __bitwise req_flags_t; 83 84 /* elevator knows about this request */ 85 #define RQF_SORTED ((__force req_flags_t)(1 << 0)) 86 /* drive already may have started this one */ 87 #define RQF_STARTED ((__force req_flags_t)(1 << 1)) 88 /* uses tagged queueing */ 89 #define RQF_QUEUED ((__force req_flags_t)(1 << 2)) 90 /* may not be passed by ioscheduler */ 91 #define RQF_SOFTBARRIER ((__force req_flags_t)(1 << 3)) 92 /* request for flush sequence */ 93 #define RQF_FLUSH_SEQ ((__force req_flags_t)(1 << 4)) 94 /* merge of different types, fail separately */ 95 #define RQF_MIXED_MERGE ((__force req_flags_t)(1 << 5)) 96 /* track inflight for MQ */ 97 #define RQF_MQ_INFLIGHT ((__force req_flags_t)(1 << 6)) 98 /* don't call prep for this one */ 99 #define RQF_DONTPREP ((__force req_flags_t)(1 << 7)) 100 /* set for "ide_preempt" requests and also for requests for which the SCSI 101 "quiesce" state must be ignored. */ 102 #define RQF_PREEMPT ((__force req_flags_t)(1 << 8)) 103 /* contains copies of user pages */ 104 #define RQF_COPY_USER ((__force req_flags_t)(1 << 9)) 105 /* vaguely specified driver internal error. Ignored by the block layer */ 106 #define RQF_FAILED ((__force req_flags_t)(1 << 10)) 107 /* don't warn about errors */ 108 #define RQF_QUIET ((__force req_flags_t)(1 << 11)) 109 /* elevator private data attached */ 110 #define RQF_ELVPRIV ((__force req_flags_t)(1 << 12)) 111 /* account I/O stat */ 112 #define RQF_IO_STAT ((__force req_flags_t)(1 << 13)) 113 /* request came from our alloc pool */ 114 #define RQF_ALLOCED ((__force req_flags_t)(1 << 14)) 115 /* runtime pm request */ 116 #define RQF_PM ((__force req_flags_t)(1 << 15)) 117 /* on IO scheduler merge hash */ 118 #define RQF_HASHED ((__force req_flags_t)(1 << 16)) 119 /* IO stats tracking on */ 120 #define RQF_STATS ((__force req_flags_t)(1 << 17)) 121 /* Look at ->special_vec for the actual data payload instead of the 122 bio chain. */ 123 #define RQF_SPECIAL_PAYLOAD ((__force req_flags_t)(1 << 18)) 124 125 /* flags that prevent us from merging requests: */ 126 #define RQF_NOMERGE_FLAGS \ 127 (RQF_STARTED | RQF_SOFTBARRIER | RQF_FLUSH_SEQ | RQF_SPECIAL_PAYLOAD) 128 129 /* 130 * Try to put the fields that are referenced together in the same cacheline. 131 * 132 * If you modify this structure, make sure to update blk_rq_init() and 133 * especially blk_mq_rq_ctx_init() to take care of the added fields. 134 */ 135 struct request { 136 struct list_head queuelist; 137 union { 138 call_single_data_t csd; 139 u64 fifo_time; 140 }; 141 142 struct request_queue *q; 143 struct blk_mq_ctx *mq_ctx; 144 145 int cpu; 146 unsigned int cmd_flags; /* op and common flags */ 147 req_flags_t rq_flags; 148 149 int internal_tag; 150 151 unsigned long atomic_flags; 152 153 /* the following two fields are internal, NEVER access directly */ 154 unsigned int __data_len; /* total data len */ 155 int tag; 156 sector_t __sector; /* sector cursor */ 157 158 struct bio *bio; 159 struct bio *biotail; 160 161 /* 162 * The hash is used inside the scheduler, and killed once the 163 * request reaches the dispatch list. The ipi_list is only used 164 * to queue the request for softirq completion, which is long 165 * after the request has been unhashed (and even removed from 166 * the dispatch list). 167 */ 168 union { 169 struct hlist_node hash; /* merge hash */ 170 struct list_head ipi_list; 171 }; 172 173 /* 174 * The rb_node is only used inside the io scheduler, requests 175 * are pruned when moved to the dispatch queue. So let the 176 * completion_data share space with the rb_node. 177 */ 178 union { 179 struct rb_node rb_node; /* sort/lookup */ 180 struct bio_vec special_vec; 181 void *completion_data; 182 int error_count; /* for legacy drivers, don't use */ 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 unsigned int timeout; 224 225 void *special; /* opaque pointer available for LLD use */ 226 227 unsigned int extra_len; /* length of alignment and padding */ 228 229 unsigned short write_hint; 230 231 unsigned long deadline; 232 struct list_head timeout_list; 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 bool blk_rq_is_scsi(struct request *rq) 245 { 246 return req_op(rq) == REQ_OP_SCSI_IN || req_op(rq) == REQ_OP_SCSI_OUT; 247 } 248 249 static inline bool blk_rq_is_private(struct request *rq) 250 { 251 return req_op(rq) == REQ_OP_DRV_IN || req_op(rq) == REQ_OP_DRV_OUT; 252 } 253 254 static inline bool blk_rq_is_passthrough(struct request *rq) 255 { 256 return blk_rq_is_scsi(rq) || blk_rq_is_private(rq); 257 } 258 259 static inline unsigned short req_get_ioprio(struct request *req) 260 { 261 return req->ioprio; 262 } 263 264 #include <linux/elevator.h> 265 266 struct blk_queue_ctx; 267 268 typedef void (request_fn_proc) (struct request_queue *q); 269 typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio); 270 typedef int (prep_rq_fn) (struct request_queue *, struct request *); 271 typedef void (unprep_rq_fn) (struct request_queue *, struct request *); 272 273 struct bio_vec; 274 typedef void (softirq_done_fn)(struct request *); 275 typedef int (dma_drain_needed_fn)(struct request *); 276 typedef int (lld_busy_fn) (struct request_queue *q); 277 typedef int (bsg_job_fn) (struct bsg_job *); 278 typedef int (init_rq_fn)(struct request_queue *, struct request *, gfp_t); 279 typedef void (exit_rq_fn)(struct request_queue *, struct request *); 280 281 enum blk_eh_timer_return { 282 BLK_EH_NOT_HANDLED, 283 BLK_EH_HANDLED, 284 BLK_EH_RESET_TIMER, 285 }; 286 287 typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); 288 289 enum blk_queue_state { 290 Queue_down, 291 Queue_up, 292 }; 293 294 struct blk_queue_tag { 295 struct request **tag_index; /* map of busy tags */ 296 unsigned long *tag_map; /* bit map of free/busy tags */ 297 int max_depth; /* what we will send to device */ 298 int real_max_depth; /* what the array can hold */ 299 atomic_t refcnt; /* map can be shared */ 300 int alloc_policy; /* tag allocation policy */ 301 int next_tag; /* next tag */ 302 }; 303 #define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */ 304 #define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */ 305 306 #define BLK_SCSI_MAX_CMDS (256) 307 #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) 308 309 /* 310 * Zoned block device models (zoned limit). 311 */ 312 enum blk_zoned_model { 313 BLK_ZONED_NONE, /* Regular block device */ 314 BLK_ZONED_HA, /* Host-aware zoned block device */ 315 BLK_ZONED_HM, /* Host-managed zoned block device */ 316 }; 317 318 struct queue_limits { 319 unsigned long bounce_pfn; 320 unsigned long seg_boundary_mask; 321 unsigned long virt_boundary_mask; 322 323 unsigned int max_hw_sectors; 324 unsigned int max_dev_sectors; 325 unsigned int chunk_sectors; 326 unsigned int max_sectors; 327 unsigned int max_segment_size; 328 unsigned int physical_block_size; 329 unsigned int alignment_offset; 330 unsigned int io_min; 331 unsigned int io_opt; 332 unsigned int max_discard_sectors; 333 unsigned int max_hw_discard_sectors; 334 unsigned int max_write_same_sectors; 335 unsigned int max_write_zeroes_sectors; 336 unsigned int discard_granularity; 337 unsigned int discard_alignment; 338 339 unsigned short logical_block_size; 340 unsigned short max_segments; 341 unsigned short max_integrity_segments; 342 unsigned short max_discard_segments; 343 344 unsigned char misaligned; 345 unsigned char discard_misaligned; 346 unsigned char cluster; 347 unsigned char raid_partial_stripes_expensive; 348 enum blk_zoned_model zoned; 349 }; 350 351 #ifdef CONFIG_BLK_DEV_ZONED 352 353 struct blk_zone_report_hdr { 354 unsigned int nr_zones; 355 u8 padding[60]; 356 }; 357 358 extern int blkdev_report_zones(struct block_device *bdev, 359 sector_t sector, struct blk_zone *zones, 360 unsigned int *nr_zones, gfp_t gfp_mask); 361 extern int blkdev_reset_zones(struct block_device *bdev, sector_t sectors, 362 sector_t nr_sectors, gfp_t gfp_mask); 363 364 extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode, 365 unsigned int cmd, unsigned long arg); 366 extern int blkdev_reset_zones_ioctl(struct block_device *bdev, fmode_t mode, 367 unsigned int cmd, unsigned long arg); 368 369 #else /* CONFIG_BLK_DEV_ZONED */ 370 371 static inline int blkdev_report_zones_ioctl(struct block_device *bdev, 372 fmode_t mode, unsigned int cmd, 373 unsigned long arg) 374 { 375 return -ENOTTY; 376 } 377 378 static inline int blkdev_reset_zones_ioctl(struct block_device *bdev, 379 fmode_t mode, unsigned int cmd, 380 unsigned long arg) 381 { 382 return -ENOTTY; 383 } 384 385 #endif /* CONFIG_BLK_DEV_ZONED */ 386 387 struct request_queue { 388 /* 389 * Together with queue_head for cacheline sharing 390 */ 391 struct list_head queue_head; 392 struct request *last_merge; 393 struct elevator_queue *elevator; 394 int nr_rqs[2]; /* # allocated [a]sync rqs */ 395 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */ 396 397 atomic_t shared_hctx_restart; 398 399 struct blk_queue_stats *stats; 400 struct rq_wb *rq_wb; 401 402 /* 403 * If blkcg is not used, @q->root_rl serves all requests. If blkcg 404 * is used, root blkg allocates from @q->root_rl and all other 405 * blkgs from their own blkg->rl. Which one to use should be 406 * determined using bio_request_list(). 407 */ 408 struct request_list root_rl; 409 410 request_fn_proc *request_fn; 411 make_request_fn *make_request_fn; 412 prep_rq_fn *prep_rq_fn; 413 unprep_rq_fn *unprep_rq_fn; 414 softirq_done_fn *softirq_done_fn; 415 rq_timed_out_fn *rq_timed_out_fn; 416 dma_drain_needed_fn *dma_drain_needed; 417 lld_busy_fn *lld_busy_fn; 418 /* Called just after a request is allocated */ 419 init_rq_fn *init_rq_fn; 420 /* Called just before a request is freed */ 421 exit_rq_fn *exit_rq_fn; 422 /* Called from inside blk_get_request() */ 423 void (*initialize_rq_fn)(struct request *rq); 424 425 const struct blk_mq_ops *mq_ops; 426 427 unsigned int *mq_map; 428 429 /* sw queues */ 430 struct blk_mq_ctx __percpu *queue_ctx; 431 unsigned int nr_queues; 432 433 unsigned int queue_depth; 434 435 /* hw dispatch queues */ 436 struct blk_mq_hw_ctx **queue_hw_ctx; 437 unsigned int nr_hw_queues; 438 439 /* 440 * Dispatch queue sorting 441 */ 442 sector_t end_sector; 443 struct request *boundary_rq; 444 445 /* 446 * Delayed queue handling 447 */ 448 struct delayed_work delay_work; 449 450 struct backing_dev_info *backing_dev_info; 451 452 /* 453 * The queue owner gets to use this for whatever they like. 454 * ll_rw_blk doesn't touch it. 455 */ 456 void *queuedata; 457 458 /* 459 * various queue flags, see QUEUE_* below 460 */ 461 unsigned long queue_flags; 462 463 /* 464 * ida allocated id for this queue. Used to index queues from 465 * ioctx. 466 */ 467 int id; 468 469 /* 470 * queue needs bounce pages for pages above this limit 471 */ 472 gfp_t bounce_gfp; 473 474 /* 475 * protects queue structures from reentrancy. ->__queue_lock should 476 * _never_ be used directly, it is queue private. always use 477 * ->queue_lock. 478 */ 479 spinlock_t __queue_lock; 480 spinlock_t *queue_lock; 481 482 /* 483 * queue kobject 484 */ 485 struct kobject kobj; 486 487 /* 488 * mq queue kobject 489 */ 490 struct kobject mq_kobj; 491 492 #ifdef CONFIG_BLK_DEV_INTEGRITY 493 struct blk_integrity integrity; 494 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 495 496 #ifdef CONFIG_PM 497 struct device *dev; 498 int rpm_status; 499 unsigned int nr_pending; 500 #endif 501 502 /* 503 * queue settings 504 */ 505 unsigned long nr_requests; /* Max # of requests */ 506 unsigned int nr_congestion_on; 507 unsigned int nr_congestion_off; 508 unsigned int nr_batching; 509 510 unsigned int dma_drain_size; 511 void *dma_drain_buffer; 512 unsigned int dma_pad_mask; 513 unsigned int dma_alignment; 514 515 struct blk_queue_tag *queue_tags; 516 struct list_head tag_busy_list; 517 518 unsigned int nr_sorted; 519 unsigned int in_flight[2]; 520 521 /* 522 * Number of active block driver functions for which blk_drain_queue() 523 * must wait. Must be incremented around functions that unlock the 524 * queue_lock internally, e.g. scsi_request_fn(). 525 */ 526 unsigned int request_fn_active; 527 528 unsigned int rq_timeout; 529 int poll_nsec; 530 531 struct blk_stat_callback *poll_cb; 532 struct blk_rq_stat poll_stat[BLK_MQ_POLL_STATS_BKTS]; 533 534 struct timer_list timeout; 535 struct work_struct timeout_work; 536 struct list_head timeout_list; 537 538 struct list_head icq_list; 539 #ifdef CONFIG_BLK_CGROUP 540 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS); 541 struct blkcg_gq *root_blkg; 542 struct list_head blkg_list; 543 #endif 544 545 struct queue_limits limits; 546 547 /* 548 * sg stuff 549 */ 550 unsigned int sg_timeout; 551 unsigned int sg_reserved_size; 552 int node; 553 #ifdef CONFIG_BLK_DEV_IO_TRACE 554 struct blk_trace *blk_trace; 555 struct mutex blk_trace_mutex; 556 #endif 557 /* 558 * for flush operations 559 */ 560 struct blk_flush_queue *fq; 561 562 struct list_head requeue_list; 563 spinlock_t requeue_lock; 564 struct delayed_work requeue_work; 565 566 struct mutex sysfs_lock; 567 568 int bypass_depth; 569 atomic_t mq_freeze_depth; 570 571 #if defined(CONFIG_BLK_DEV_BSG) 572 bsg_job_fn *bsg_job_fn; 573 struct bsg_class_device bsg_dev; 574 #endif 575 576 #ifdef CONFIG_BLK_DEV_THROTTLING 577 /* Throttle data */ 578 struct throtl_data *td; 579 #endif 580 struct rcu_head rcu_head; 581 wait_queue_head_t mq_freeze_wq; 582 struct percpu_ref q_usage_counter; 583 struct list_head all_q_node; 584 585 struct blk_mq_tag_set *tag_set; 586 struct list_head tag_set_list; 587 struct bio_set *bio_split; 588 589 #ifdef CONFIG_BLK_DEBUG_FS 590 struct dentry *debugfs_dir; 591 struct dentry *sched_debugfs_dir; 592 #endif 593 594 bool mq_sysfs_init_done; 595 596 size_t cmd_size; 597 void *rq_alloc_data; 598 599 struct work_struct release_work; 600 601 #define BLK_MAX_WRITE_HINTS 5 602 u64 write_hints[BLK_MAX_WRITE_HINTS]; 603 }; 604 605 #define QUEUE_FLAG_QUEUED 0 /* uses generic tag queueing */ 606 #define QUEUE_FLAG_STOPPED 1 /* queue is stopped */ 607 #define QUEUE_FLAG_DYING 2 /* queue being torn down */ 608 #define QUEUE_FLAG_BYPASS 3 /* act as dumb FIFO queue */ 609 #define QUEUE_FLAG_BIDI 4 /* queue supports bidi requests */ 610 #define QUEUE_FLAG_NOMERGES 5 /* disable merge attempts */ 611 #define QUEUE_FLAG_SAME_COMP 6 /* complete on same CPU-group */ 612 #define QUEUE_FLAG_FAIL_IO 7 /* fake timeout */ 613 #define QUEUE_FLAG_STACKABLE 8 /* supports request stacking */ 614 #define QUEUE_FLAG_NONROT 9 /* non-rotational device (SSD) */ 615 #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ 616 #define QUEUE_FLAG_IO_STAT 10 /* do IO stats */ 617 #define QUEUE_FLAG_DISCARD 11 /* supports DISCARD */ 618 #define QUEUE_FLAG_NOXMERGES 12 /* No extended merges */ 619 #define QUEUE_FLAG_ADD_RANDOM 13 /* Contributes to random pool */ 620 #define QUEUE_FLAG_SECERASE 14 /* supports secure erase */ 621 #define QUEUE_FLAG_SAME_FORCE 15 /* force complete on same CPU */ 622 #define QUEUE_FLAG_DEAD 16 /* queue tear-down finished */ 623 #define QUEUE_FLAG_INIT_DONE 17 /* queue is initialized */ 624 #define QUEUE_FLAG_NO_SG_MERGE 18 /* don't attempt to merge SG segments*/ 625 #define QUEUE_FLAG_POLL 19 /* IO polling enabled if set */ 626 #define QUEUE_FLAG_WC 20 /* Write back caching */ 627 #define QUEUE_FLAG_FUA 21 /* device supports FUA writes */ 628 #define QUEUE_FLAG_FLUSH_NQ 22 /* flush not queueuable */ 629 #define QUEUE_FLAG_DAX 23 /* device supports DAX */ 630 #define QUEUE_FLAG_STATS 24 /* track rq completion times */ 631 #define QUEUE_FLAG_POLL_STATS 25 /* collecting stats for hybrid polling */ 632 #define QUEUE_FLAG_REGISTERED 26 /* queue has been registered to a disk */ 633 #define QUEUE_FLAG_SCSI_PASSTHROUGH 27 /* queue supports SCSI commands */ 634 #define QUEUE_FLAG_QUIESCED 28 /* queue has been quiesced */ 635 636 #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 637 (1 << QUEUE_FLAG_STACKABLE) | \ 638 (1 << QUEUE_FLAG_SAME_COMP) | \ 639 (1 << QUEUE_FLAG_ADD_RANDOM)) 640 641 #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ 642 (1 << QUEUE_FLAG_STACKABLE) | \ 643 (1 << QUEUE_FLAG_SAME_COMP) | \ 644 (1 << QUEUE_FLAG_POLL)) 645 646 /* 647 * @q->queue_lock is set while a queue is being initialized. Since we know 648 * that no other threads access the queue object before @q->queue_lock has 649 * been set, it is safe to manipulate queue flags without holding the 650 * queue_lock if @q->queue_lock == NULL. See also blk_alloc_queue_node() and 651 * blk_init_allocated_queue(). 652 */ 653 static inline void queue_lockdep_assert_held(struct request_queue *q) 654 { 655 if (q->queue_lock) 656 lockdep_assert_held(q->queue_lock); 657 } 658 659 static inline void queue_flag_set_unlocked(unsigned int flag, 660 struct request_queue *q) 661 { 662 __set_bit(flag, &q->queue_flags); 663 } 664 665 static inline int queue_flag_test_and_clear(unsigned int flag, 666 struct request_queue *q) 667 { 668 queue_lockdep_assert_held(q); 669 670 if (test_bit(flag, &q->queue_flags)) { 671 __clear_bit(flag, &q->queue_flags); 672 return 1; 673 } 674 675 return 0; 676 } 677 678 static inline int queue_flag_test_and_set(unsigned int flag, 679 struct request_queue *q) 680 { 681 queue_lockdep_assert_held(q); 682 683 if (!test_bit(flag, &q->queue_flags)) { 684 __set_bit(flag, &q->queue_flags); 685 return 0; 686 } 687 688 return 1; 689 } 690 691 static inline void queue_flag_set(unsigned int flag, struct request_queue *q) 692 { 693 queue_lockdep_assert_held(q); 694 __set_bit(flag, &q->queue_flags); 695 } 696 697 static inline void queue_flag_clear_unlocked(unsigned int flag, 698 struct request_queue *q) 699 { 700 __clear_bit(flag, &q->queue_flags); 701 } 702 703 static inline int queue_in_flight(struct request_queue *q) 704 { 705 return q->in_flight[0] + q->in_flight[1]; 706 } 707 708 static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) 709 { 710 queue_lockdep_assert_held(q); 711 __clear_bit(flag, &q->queue_flags); 712 } 713 714 #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) 715 #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) 716 #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags) 717 #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags) 718 #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags) 719 #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags) 720 #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) 721 #define blk_queue_noxmerges(q) \ 722 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags) 723 #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) 724 #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) 725 #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags) 726 #define blk_queue_stackable(q) \ 727 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) 728 #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) 729 #define blk_queue_secure_erase(q) \ 730 (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags)) 731 #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags) 732 #define blk_queue_scsi_passthrough(q) \ 733 test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags) 734 735 #define blk_noretry_request(rq) \ 736 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ 737 REQ_FAILFAST_DRIVER)) 738 #define blk_queue_quiesced(q) test_bit(QUEUE_FLAG_QUIESCED, &(q)->queue_flags) 739 740 static inline bool blk_account_rq(struct request *rq) 741 { 742 return (rq->rq_flags & RQF_STARTED) && !blk_rq_is_passthrough(rq); 743 } 744 745 #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) 746 #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) 747 /* rq->queuelist of dequeued request must be list_empty() */ 748 #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) 749 750 #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) 751 752 #define rq_data_dir(rq) (op_is_write(req_op(rq)) ? WRITE : READ) 753 754 /* 755 * Driver can handle struct request, if it either has an old style 756 * request_fn defined, or is blk-mq based. 757 */ 758 static inline bool queue_is_rq_based(struct request_queue *q) 759 { 760 return q->request_fn || q->mq_ops; 761 } 762 763 static inline unsigned int blk_queue_cluster(struct request_queue *q) 764 { 765 return q->limits.cluster; 766 } 767 768 static inline enum blk_zoned_model 769 blk_queue_zoned_model(struct request_queue *q) 770 { 771 return q->limits.zoned; 772 } 773 774 static inline bool blk_queue_is_zoned(struct request_queue *q) 775 { 776 switch (blk_queue_zoned_model(q)) { 777 case BLK_ZONED_HA: 778 case BLK_ZONED_HM: 779 return true; 780 default: 781 return false; 782 } 783 } 784 785 static inline unsigned int blk_queue_zone_sectors(struct request_queue *q) 786 { 787 return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0; 788 } 789 790 static inline bool rq_is_sync(struct request *rq) 791 { 792 return op_is_sync(rq->cmd_flags); 793 } 794 795 static inline bool blk_rl_full(struct request_list *rl, bool sync) 796 { 797 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 798 799 return rl->flags & flag; 800 } 801 802 static inline void blk_set_rl_full(struct request_list *rl, bool sync) 803 { 804 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 805 806 rl->flags |= flag; 807 } 808 809 static inline void blk_clear_rl_full(struct request_list *rl, bool sync) 810 { 811 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL; 812 813 rl->flags &= ~flag; 814 } 815 816 static inline bool rq_mergeable(struct request *rq) 817 { 818 if (blk_rq_is_passthrough(rq)) 819 return false; 820 821 if (req_op(rq) == REQ_OP_FLUSH) 822 return false; 823 824 if (req_op(rq) == REQ_OP_WRITE_ZEROES) 825 return false; 826 827 if (rq->cmd_flags & REQ_NOMERGE_FLAGS) 828 return false; 829 if (rq->rq_flags & RQF_NOMERGE_FLAGS) 830 return false; 831 832 return true; 833 } 834 835 static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b) 836 { 837 if (bio_page(a) == bio_page(b) && 838 bio_offset(a) == bio_offset(b)) 839 return true; 840 841 return false; 842 } 843 844 static inline unsigned int blk_queue_depth(struct request_queue *q) 845 { 846 if (q->queue_depth) 847 return q->queue_depth; 848 849 return q->nr_requests; 850 } 851 852 /* 853 * q->prep_rq_fn return values 854 */ 855 enum { 856 BLKPREP_OK, /* serve it */ 857 BLKPREP_KILL, /* fatal error, kill, return -EIO */ 858 BLKPREP_DEFER, /* leave on queue */ 859 BLKPREP_INVALID, /* invalid command, kill, return -EREMOTEIO */ 860 }; 861 862 extern unsigned long blk_max_low_pfn, blk_max_pfn; 863 864 /* 865 * standard bounce addresses: 866 * 867 * BLK_BOUNCE_HIGH : bounce all highmem pages 868 * BLK_BOUNCE_ANY : don't bounce anything 869 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary 870 */ 871 872 #if BITS_PER_LONG == 32 873 #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) 874 #else 875 #define BLK_BOUNCE_HIGH -1ULL 876 #endif 877 #define BLK_BOUNCE_ANY (-1ULL) 878 #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24)) 879 880 /* 881 * default timeout for SG_IO if none specified 882 */ 883 #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) 884 #define BLK_MIN_SG_TIMEOUT (7 * HZ) 885 886 struct rq_map_data { 887 struct page **pages; 888 int page_order; 889 int nr_entries; 890 unsigned long offset; 891 int null_mapped; 892 int from_user; 893 }; 894 895 struct req_iterator { 896 struct bvec_iter iter; 897 struct bio *bio; 898 }; 899 900 /* This should not be used directly - use rq_for_each_segment */ 901 #define for_each_bio(_bio) \ 902 for (; _bio; _bio = _bio->bi_next) 903 #define __rq_for_each_bio(_bio, rq) \ 904 if ((rq->bio)) \ 905 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) 906 907 #define rq_for_each_segment(bvl, _rq, _iter) \ 908 __rq_for_each_bio(_iter.bio, _rq) \ 909 bio_for_each_segment(bvl, _iter.bio, _iter.iter) 910 911 #define rq_iter_last(bvec, _iter) \ 912 (_iter.bio->bi_next == NULL && \ 913 bio_iter_last(bvec, _iter.iter)) 914 915 #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 916 # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" 917 #endif 918 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 919 extern void rq_flush_dcache_pages(struct request *rq); 920 #else 921 static inline void rq_flush_dcache_pages(struct request *rq) 922 { 923 } 924 #endif 925 926 #ifdef CONFIG_PRINTK 927 #define vfs_msg(sb, level, fmt, ...) \ 928 __vfs_msg(sb, level, fmt, ##__VA_ARGS__) 929 #else 930 #define vfs_msg(sb, level, fmt, ...) \ 931 do { \ 932 no_printk(fmt, ##__VA_ARGS__); \ 933 __vfs_msg(sb, "", " "); \ 934 } while (0) 935 #endif 936 937 extern int blk_register_queue(struct gendisk *disk); 938 extern void blk_unregister_queue(struct gendisk *disk); 939 extern blk_qc_t generic_make_request(struct bio *bio); 940 extern void blk_rq_init(struct request_queue *q, struct request *rq); 941 extern void blk_init_request_from_bio(struct request *req, struct bio *bio); 942 extern void blk_put_request(struct request *); 943 extern void __blk_put_request(struct request_queue *, struct request *); 944 extern struct request *blk_get_request(struct request_queue *, unsigned int op, 945 gfp_t gfp_mask); 946 extern void blk_requeue_request(struct request_queue *, struct request *); 947 extern int blk_lld_busy(struct request_queue *q); 948 extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, 949 struct bio_set *bs, gfp_t gfp_mask, 950 int (*bio_ctr)(struct bio *, struct bio *, void *), 951 void *data); 952 extern void blk_rq_unprep_clone(struct request *rq); 953 extern blk_status_t blk_insert_cloned_request(struct request_queue *q, 954 struct request *rq); 955 extern int blk_rq_append_bio(struct request *rq, struct bio *bio); 956 extern void blk_delay_queue(struct request_queue *, unsigned long); 957 extern void blk_queue_split(struct request_queue *, struct bio **); 958 extern void blk_recount_segments(struct request_queue *, struct bio *); 959 extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int); 960 extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t, 961 unsigned int, void __user *); 962 extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, 963 unsigned int, void __user *); 964 extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, 965 struct scsi_ioctl_command __user *); 966 967 extern int blk_queue_enter(struct request_queue *q, bool nowait); 968 extern void blk_queue_exit(struct request_queue *q); 969 extern void blk_start_queue(struct request_queue *q); 970 extern void blk_start_queue_async(struct request_queue *q); 971 extern void blk_stop_queue(struct request_queue *q); 972 extern void blk_sync_queue(struct request_queue *q); 973 extern void __blk_stop_queue(struct request_queue *q); 974 extern void __blk_run_queue(struct request_queue *q); 975 extern void __blk_run_queue_uncond(struct request_queue *q); 976 extern void blk_run_queue(struct request_queue *); 977 extern void blk_run_queue_async(struct request_queue *q); 978 extern int blk_rq_map_user(struct request_queue *, struct request *, 979 struct rq_map_data *, void __user *, unsigned long, 980 gfp_t); 981 extern int blk_rq_unmap_user(struct bio *); 982 extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); 983 extern int blk_rq_map_user_iov(struct request_queue *, struct request *, 984 struct rq_map_data *, const struct iov_iter *, 985 gfp_t); 986 extern void blk_execute_rq(struct request_queue *, struct gendisk *, 987 struct request *, int); 988 extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, 989 struct request *, int, rq_end_io_fn *); 990 991 int blk_status_to_errno(blk_status_t status); 992 blk_status_t errno_to_blk_status(int errno); 993 994 bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie); 995 996 static inline struct request_queue *bdev_get_queue(struct block_device *bdev) 997 { 998 return bdev->bd_disk->queue; /* this is never NULL */ 999 } 1000 1001 /* 1002 * blk_rq_pos() : the current sector 1003 * blk_rq_bytes() : bytes left in the entire request 1004 * blk_rq_cur_bytes() : bytes left in the current segment 1005 * blk_rq_err_bytes() : bytes left till the next error boundary 1006 * blk_rq_sectors() : sectors left in the entire request 1007 * blk_rq_cur_sectors() : sectors left in the current segment 1008 */ 1009 static inline sector_t blk_rq_pos(const struct request *rq) 1010 { 1011 return rq->__sector; 1012 } 1013 1014 static inline unsigned int blk_rq_bytes(const struct request *rq) 1015 { 1016 return rq->__data_len; 1017 } 1018 1019 static inline int blk_rq_cur_bytes(const struct request *rq) 1020 { 1021 return rq->bio ? bio_cur_bytes(rq->bio) : 0; 1022 } 1023 1024 extern unsigned int blk_rq_err_bytes(const struct request *rq); 1025 1026 static inline unsigned int blk_rq_sectors(const struct request *rq) 1027 { 1028 return blk_rq_bytes(rq) >> 9; 1029 } 1030 1031 static inline unsigned int blk_rq_cur_sectors(const struct request *rq) 1032 { 1033 return blk_rq_cur_bytes(rq) >> 9; 1034 } 1035 1036 /* 1037 * Some commands like WRITE SAME have a payload or data transfer size which 1038 * is different from the size of the request. Any driver that supports such 1039 * commands using the RQF_SPECIAL_PAYLOAD flag needs to use this helper to 1040 * calculate the data transfer size. 1041 */ 1042 static inline unsigned int blk_rq_payload_bytes(struct request *rq) 1043 { 1044 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD) 1045 return rq->special_vec.bv_len; 1046 return blk_rq_bytes(rq); 1047 } 1048 1049 static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q, 1050 int op) 1051 { 1052 if (unlikely(op == REQ_OP_DISCARD || op == REQ_OP_SECURE_ERASE)) 1053 return min(q->limits.max_discard_sectors, UINT_MAX >> 9); 1054 1055 if (unlikely(op == REQ_OP_WRITE_SAME)) 1056 return q->limits.max_write_same_sectors; 1057 1058 if (unlikely(op == REQ_OP_WRITE_ZEROES)) 1059 return q->limits.max_write_zeroes_sectors; 1060 1061 return q->limits.max_sectors; 1062 } 1063 1064 /* 1065 * Return maximum size of a request at given offset. Only valid for 1066 * file system requests. 1067 */ 1068 static inline unsigned int blk_max_size_offset(struct request_queue *q, 1069 sector_t offset) 1070 { 1071 if (!q->limits.chunk_sectors) 1072 return q->limits.max_sectors; 1073 1074 return q->limits.chunk_sectors - 1075 (offset & (q->limits.chunk_sectors - 1)); 1076 } 1077 1078 static inline unsigned int blk_rq_get_max_sectors(struct request *rq, 1079 sector_t offset) 1080 { 1081 struct request_queue *q = rq->q; 1082 1083 if (blk_rq_is_passthrough(rq)) 1084 return q->limits.max_hw_sectors; 1085 1086 if (!q->limits.chunk_sectors || 1087 req_op(rq) == REQ_OP_DISCARD || 1088 req_op(rq) == REQ_OP_SECURE_ERASE) 1089 return blk_queue_get_max_sectors(q, req_op(rq)); 1090 1091 return min(blk_max_size_offset(q, offset), 1092 blk_queue_get_max_sectors(q, req_op(rq))); 1093 } 1094 1095 static inline unsigned int blk_rq_count_bios(struct request *rq) 1096 { 1097 unsigned int nr_bios = 0; 1098 struct bio *bio; 1099 1100 __rq_for_each_bio(bio, rq) 1101 nr_bios++; 1102 1103 return nr_bios; 1104 } 1105 1106 /* 1107 * Request issue related functions. 1108 */ 1109 extern struct request *blk_peek_request(struct request_queue *q); 1110 extern void blk_start_request(struct request *rq); 1111 extern struct request *blk_fetch_request(struct request_queue *q); 1112 1113 /* 1114 * Request completion related functions. 1115 * 1116 * blk_update_request() completes given number of bytes and updates 1117 * the request without completing it. 1118 * 1119 * blk_end_request() and friends. __blk_end_request() must be called 1120 * with the request queue spinlock acquired. 1121 * 1122 * Several drivers define their own end_request and call 1123 * blk_end_request() for parts of the original function. 1124 * This prevents code duplication in drivers. 1125 */ 1126 extern bool blk_update_request(struct request *rq, blk_status_t error, 1127 unsigned int nr_bytes); 1128 extern void blk_finish_request(struct request *rq, blk_status_t error); 1129 extern bool blk_end_request(struct request *rq, blk_status_t error, 1130 unsigned int nr_bytes); 1131 extern void blk_end_request_all(struct request *rq, blk_status_t error); 1132 extern bool __blk_end_request(struct request *rq, blk_status_t error, 1133 unsigned int nr_bytes); 1134 extern void __blk_end_request_all(struct request *rq, blk_status_t error); 1135 extern bool __blk_end_request_cur(struct request *rq, blk_status_t error); 1136 1137 extern void blk_complete_request(struct request *); 1138 extern void __blk_complete_request(struct request *); 1139 extern void blk_abort_request(struct request *); 1140 extern void blk_unprep_request(struct request *); 1141 1142 /* 1143 * Access functions for manipulating queue properties 1144 */ 1145 extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, 1146 spinlock_t *lock, int node_id); 1147 extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); 1148 extern int blk_init_allocated_queue(struct request_queue *); 1149 extern void blk_cleanup_queue(struct request_queue *); 1150 extern void blk_queue_make_request(struct request_queue *, make_request_fn *); 1151 extern void blk_queue_bounce_limit(struct request_queue *, u64); 1152 extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); 1153 extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int); 1154 extern void blk_queue_max_segments(struct request_queue *, unsigned short); 1155 extern void blk_queue_max_discard_segments(struct request_queue *, 1156 unsigned short); 1157 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); 1158 extern void blk_queue_max_discard_sectors(struct request_queue *q, 1159 unsigned int max_discard_sectors); 1160 extern void blk_queue_max_write_same_sectors(struct request_queue *q, 1161 unsigned int max_write_same_sectors); 1162 extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q, 1163 unsigned int max_write_same_sectors); 1164 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); 1165 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); 1166 extern void blk_queue_alignment_offset(struct request_queue *q, 1167 unsigned int alignment); 1168 extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); 1169 extern void blk_queue_io_min(struct request_queue *q, unsigned int min); 1170 extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); 1171 extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); 1172 extern void blk_set_queue_depth(struct request_queue *q, unsigned int depth); 1173 extern void blk_set_default_limits(struct queue_limits *lim); 1174 extern void blk_set_stacking_limits(struct queue_limits *lim); 1175 extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, 1176 sector_t offset); 1177 extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, 1178 sector_t offset); 1179 extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, 1180 sector_t offset); 1181 extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); 1182 extern void blk_queue_dma_pad(struct request_queue *, unsigned int); 1183 extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); 1184 extern int blk_queue_dma_drain(struct request_queue *q, 1185 dma_drain_needed_fn *dma_drain_needed, 1186 void *buf, unsigned int size); 1187 extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); 1188 extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); 1189 extern void blk_queue_virt_boundary(struct request_queue *, unsigned long); 1190 extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); 1191 extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn); 1192 extern void blk_queue_dma_alignment(struct request_queue *, int); 1193 extern void blk_queue_update_dma_alignment(struct request_queue *, int); 1194 extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); 1195 extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); 1196 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); 1197 extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable); 1198 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua); 1199 1200 /* 1201 * Number of physical segments as sent to the device. 1202 * 1203 * Normally this is the number of discontiguous data segments sent by the 1204 * submitter. But for data-less command like discard we might have no 1205 * actual data segments submitted, but the driver might have to add it's 1206 * own special payload. In that case we still return 1 here so that this 1207 * special payload will be mapped. 1208 */ 1209 static inline unsigned short blk_rq_nr_phys_segments(struct request *rq) 1210 { 1211 if (rq->rq_flags & RQF_SPECIAL_PAYLOAD) 1212 return 1; 1213 return rq->nr_phys_segments; 1214 } 1215 1216 /* 1217 * Number of discard segments (or ranges) the driver needs to fill in. 1218 * Each discard bio merged into a request is counted as one segment. 1219 */ 1220 static inline unsigned short blk_rq_nr_discard_segments(struct request *rq) 1221 { 1222 return max_t(unsigned short, rq->nr_phys_segments, 1); 1223 } 1224 1225 extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); 1226 extern void blk_dump_rq_flags(struct request *, char *); 1227 extern long nr_blockdev_pages(void); 1228 1229 bool __must_check blk_get_queue(struct request_queue *); 1230 struct request_queue *blk_alloc_queue(gfp_t); 1231 struct request_queue *blk_alloc_queue_node(gfp_t, int); 1232 extern void blk_put_queue(struct request_queue *); 1233 extern void blk_set_queue_dying(struct request_queue *); 1234 1235 /* 1236 * block layer runtime pm functions 1237 */ 1238 #ifdef CONFIG_PM 1239 extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev); 1240 extern int blk_pre_runtime_suspend(struct request_queue *q); 1241 extern void blk_post_runtime_suspend(struct request_queue *q, int err); 1242 extern void blk_pre_runtime_resume(struct request_queue *q); 1243 extern void blk_post_runtime_resume(struct request_queue *q, int err); 1244 extern void blk_set_runtime_active(struct request_queue *q); 1245 #else 1246 static inline void blk_pm_runtime_init(struct request_queue *q, 1247 struct device *dev) {} 1248 static inline int blk_pre_runtime_suspend(struct request_queue *q) 1249 { 1250 return -ENOSYS; 1251 } 1252 static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {} 1253 static inline void blk_pre_runtime_resume(struct request_queue *q) {} 1254 static inline void blk_post_runtime_resume(struct request_queue *q, int err) {} 1255 static inline void blk_set_runtime_active(struct request_queue *q) {} 1256 #endif 1257 1258 /* 1259 * blk_plug permits building a queue of related requests by holding the I/O 1260 * fragments for a short period. This allows merging of sequential requests 1261 * into single larger request. As the requests are moved from a per-task list to 1262 * the device's request_queue in a batch, this results in improved scalability 1263 * as the lock contention for request_queue lock is reduced. 1264 * 1265 * It is ok not to disable preemption when adding the request to the plug list 1266 * or when attempting a merge, because blk_schedule_flush_list() will only flush 1267 * the plug list when the task sleeps by itself. For details, please see 1268 * schedule() where blk_schedule_flush_plug() is called. 1269 */ 1270 struct blk_plug { 1271 struct list_head list; /* requests */ 1272 struct list_head mq_list; /* blk-mq requests */ 1273 struct list_head cb_list; /* md requires an unplug callback */ 1274 }; 1275 #define BLK_MAX_REQUEST_COUNT 16 1276 #define BLK_PLUG_FLUSH_SIZE (128 * 1024) 1277 1278 struct blk_plug_cb; 1279 typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool); 1280 struct blk_plug_cb { 1281 struct list_head list; 1282 blk_plug_cb_fn callback; 1283 void *data; 1284 }; 1285 extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, 1286 void *data, int size); 1287 extern void blk_start_plug(struct blk_plug *); 1288 extern void blk_finish_plug(struct blk_plug *); 1289 extern void blk_flush_plug_list(struct blk_plug *, bool); 1290 1291 static inline void blk_flush_plug(struct task_struct *tsk) 1292 { 1293 struct blk_plug *plug = tsk->plug; 1294 1295 if (plug) 1296 blk_flush_plug_list(plug, false); 1297 } 1298 1299 static inline void blk_schedule_flush_plug(struct task_struct *tsk) 1300 { 1301 struct blk_plug *plug = tsk->plug; 1302 1303 if (plug) 1304 blk_flush_plug_list(plug, true); 1305 } 1306 1307 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1308 { 1309 struct blk_plug *plug = tsk->plug; 1310 1311 return plug && 1312 (!list_empty(&plug->list) || 1313 !list_empty(&plug->mq_list) || 1314 !list_empty(&plug->cb_list)); 1315 } 1316 1317 /* 1318 * tag stuff 1319 */ 1320 extern int blk_queue_start_tag(struct request_queue *, struct request *); 1321 extern struct request *blk_queue_find_tag(struct request_queue *, int); 1322 extern void blk_queue_end_tag(struct request_queue *, struct request *); 1323 extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int); 1324 extern void blk_queue_free_tags(struct request_queue *); 1325 extern int blk_queue_resize_tags(struct request_queue *, int); 1326 extern void blk_queue_invalidate_tags(struct request_queue *); 1327 extern struct blk_queue_tag *blk_init_tags(int, int); 1328 extern void blk_free_tags(struct blk_queue_tag *); 1329 1330 static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, 1331 int tag) 1332 { 1333 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) 1334 return NULL; 1335 return bqt->tag_index[tag]; 1336 } 1337 1338 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); 1339 extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, 1340 sector_t nr_sects, gfp_t gfp_mask, struct page *page); 1341 1342 #define BLKDEV_DISCARD_SECURE (1 << 0) /* issue a secure erase */ 1343 1344 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1345 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags); 1346 extern int __blkdev_issue_discard(struct block_device *bdev, sector_t sector, 1347 sector_t nr_sects, gfp_t gfp_mask, int flags, 1348 struct bio **biop); 1349 1350 #define BLKDEV_ZERO_NOUNMAP (1 << 0) /* do not free blocks */ 1351 #define BLKDEV_ZERO_NOFALLBACK (1 << 1) /* don't write explicit zeroes */ 1352 1353 extern int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1354 sector_t nr_sects, gfp_t gfp_mask, struct bio **biop, 1355 unsigned flags); 1356 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector, 1357 sector_t nr_sects, gfp_t gfp_mask, unsigned flags); 1358 1359 static inline int sb_issue_discard(struct super_block *sb, sector_t block, 1360 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags) 1361 { 1362 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9), 1363 nr_blocks << (sb->s_blocksize_bits - 9), 1364 gfp_mask, flags); 1365 } 1366 static inline int sb_issue_zeroout(struct super_block *sb, sector_t block, 1367 sector_t nr_blocks, gfp_t gfp_mask) 1368 { 1369 return blkdev_issue_zeroout(sb->s_bdev, 1370 block << (sb->s_blocksize_bits - 9), 1371 nr_blocks << (sb->s_blocksize_bits - 9), 1372 gfp_mask, 0); 1373 } 1374 1375 extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); 1376 1377 enum blk_default_limits { 1378 BLK_MAX_SEGMENTS = 128, 1379 BLK_SAFE_MAX_SECTORS = 255, 1380 BLK_DEF_MAX_SECTORS = 2560, 1381 BLK_MAX_SEGMENT_SIZE = 65536, 1382 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL, 1383 }; 1384 1385 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) 1386 1387 static inline unsigned long queue_segment_boundary(struct request_queue *q) 1388 { 1389 return q->limits.seg_boundary_mask; 1390 } 1391 1392 static inline unsigned long queue_virt_boundary(struct request_queue *q) 1393 { 1394 return q->limits.virt_boundary_mask; 1395 } 1396 1397 static inline unsigned int queue_max_sectors(struct request_queue *q) 1398 { 1399 return q->limits.max_sectors; 1400 } 1401 1402 static inline unsigned int queue_max_hw_sectors(struct request_queue *q) 1403 { 1404 return q->limits.max_hw_sectors; 1405 } 1406 1407 static inline unsigned short queue_max_segments(struct request_queue *q) 1408 { 1409 return q->limits.max_segments; 1410 } 1411 1412 static inline unsigned short queue_max_discard_segments(struct request_queue *q) 1413 { 1414 return q->limits.max_discard_segments; 1415 } 1416 1417 static inline unsigned int queue_max_segment_size(struct request_queue *q) 1418 { 1419 return q->limits.max_segment_size; 1420 } 1421 1422 static inline unsigned short queue_logical_block_size(struct request_queue *q) 1423 { 1424 int retval = 512; 1425 1426 if (q && q->limits.logical_block_size) 1427 retval = q->limits.logical_block_size; 1428 1429 return retval; 1430 } 1431 1432 static inline unsigned short bdev_logical_block_size(struct block_device *bdev) 1433 { 1434 return queue_logical_block_size(bdev_get_queue(bdev)); 1435 } 1436 1437 static inline unsigned int queue_physical_block_size(struct request_queue *q) 1438 { 1439 return q->limits.physical_block_size; 1440 } 1441 1442 static inline unsigned int bdev_physical_block_size(struct block_device *bdev) 1443 { 1444 return queue_physical_block_size(bdev_get_queue(bdev)); 1445 } 1446 1447 static inline unsigned int queue_io_min(struct request_queue *q) 1448 { 1449 return q->limits.io_min; 1450 } 1451 1452 static inline int bdev_io_min(struct block_device *bdev) 1453 { 1454 return queue_io_min(bdev_get_queue(bdev)); 1455 } 1456 1457 static inline unsigned int queue_io_opt(struct request_queue *q) 1458 { 1459 return q->limits.io_opt; 1460 } 1461 1462 static inline int bdev_io_opt(struct block_device *bdev) 1463 { 1464 return queue_io_opt(bdev_get_queue(bdev)); 1465 } 1466 1467 static inline int queue_alignment_offset(struct request_queue *q) 1468 { 1469 if (q->limits.misaligned) 1470 return -1; 1471 1472 return q->limits.alignment_offset; 1473 } 1474 1475 static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector) 1476 { 1477 unsigned int granularity = max(lim->physical_block_size, lim->io_min); 1478 unsigned int alignment = sector_div(sector, granularity >> 9) << 9; 1479 1480 return (granularity + lim->alignment_offset - alignment) % granularity; 1481 } 1482 1483 static inline int bdev_alignment_offset(struct block_device *bdev) 1484 { 1485 struct request_queue *q = bdev_get_queue(bdev); 1486 1487 if (q->limits.misaligned) 1488 return -1; 1489 1490 if (bdev != bdev->bd_contains) 1491 return bdev->bd_part->alignment_offset; 1492 1493 return q->limits.alignment_offset; 1494 } 1495 1496 static inline int queue_discard_alignment(struct request_queue *q) 1497 { 1498 if (q->limits.discard_misaligned) 1499 return -1; 1500 1501 return q->limits.discard_alignment; 1502 } 1503 1504 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector) 1505 { 1506 unsigned int alignment, granularity, offset; 1507 1508 if (!lim->max_discard_sectors) 1509 return 0; 1510 1511 /* Why are these in bytes, not sectors? */ 1512 alignment = lim->discard_alignment >> 9; 1513 granularity = lim->discard_granularity >> 9; 1514 if (!granularity) 1515 return 0; 1516 1517 /* Offset of the partition start in 'granularity' sectors */ 1518 offset = sector_div(sector, granularity); 1519 1520 /* And why do we do this modulus *again* in blkdev_issue_discard()? */ 1521 offset = (granularity + alignment - offset) % granularity; 1522 1523 /* Turn it back into bytes, gaah */ 1524 return offset << 9; 1525 } 1526 1527 static inline int bdev_discard_alignment(struct block_device *bdev) 1528 { 1529 struct request_queue *q = bdev_get_queue(bdev); 1530 1531 if (bdev != bdev->bd_contains) 1532 return bdev->bd_part->discard_alignment; 1533 1534 return q->limits.discard_alignment; 1535 } 1536 1537 static inline unsigned int bdev_write_same(struct block_device *bdev) 1538 { 1539 struct request_queue *q = bdev_get_queue(bdev); 1540 1541 if (q) 1542 return q->limits.max_write_same_sectors; 1543 1544 return 0; 1545 } 1546 1547 static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev) 1548 { 1549 struct request_queue *q = bdev_get_queue(bdev); 1550 1551 if (q) 1552 return q->limits.max_write_zeroes_sectors; 1553 1554 return 0; 1555 } 1556 1557 static inline enum blk_zoned_model bdev_zoned_model(struct block_device *bdev) 1558 { 1559 struct request_queue *q = bdev_get_queue(bdev); 1560 1561 if (q) 1562 return blk_queue_zoned_model(q); 1563 1564 return BLK_ZONED_NONE; 1565 } 1566 1567 static inline bool bdev_is_zoned(struct block_device *bdev) 1568 { 1569 struct request_queue *q = bdev_get_queue(bdev); 1570 1571 if (q) 1572 return blk_queue_is_zoned(q); 1573 1574 return false; 1575 } 1576 1577 static inline unsigned int bdev_zone_sectors(struct block_device *bdev) 1578 { 1579 struct request_queue *q = bdev_get_queue(bdev); 1580 1581 if (q) 1582 return blk_queue_zone_sectors(q); 1583 1584 return 0; 1585 } 1586 1587 static inline int queue_dma_alignment(struct request_queue *q) 1588 { 1589 return q ? q->dma_alignment : 511; 1590 } 1591 1592 static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr, 1593 unsigned int len) 1594 { 1595 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; 1596 return !(addr & alignment) && !(len & alignment); 1597 } 1598 1599 /* assumes size > 256 */ 1600 static inline unsigned int blksize_bits(unsigned int size) 1601 { 1602 unsigned int bits = 8; 1603 do { 1604 bits++; 1605 size >>= 1; 1606 } while (size > 256); 1607 return bits; 1608 } 1609 1610 static inline unsigned int block_size(struct block_device *bdev) 1611 { 1612 return bdev->bd_block_size; 1613 } 1614 1615 static inline bool queue_flush_queueable(struct request_queue *q) 1616 { 1617 return !test_bit(QUEUE_FLAG_FLUSH_NQ, &q->queue_flags); 1618 } 1619 1620 typedef struct {struct page *v;} Sector; 1621 1622 unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); 1623 1624 static inline void put_dev_sector(Sector p) 1625 { 1626 put_page(p.v); 1627 } 1628 1629 static inline bool __bvec_gap_to_prev(struct request_queue *q, 1630 struct bio_vec *bprv, unsigned int offset) 1631 { 1632 return offset || 1633 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); 1634 } 1635 1636 /* 1637 * Check if adding a bio_vec after bprv with offset would create a gap in 1638 * the SG list. Most drivers don't care about this, but some do. 1639 */ 1640 static inline bool bvec_gap_to_prev(struct request_queue *q, 1641 struct bio_vec *bprv, unsigned int offset) 1642 { 1643 if (!queue_virt_boundary(q)) 1644 return false; 1645 return __bvec_gap_to_prev(q, bprv, offset); 1646 } 1647 1648 /* 1649 * Check if the two bvecs from two bios can be merged to one segment. 1650 * If yes, no need to check gap between the two bios since the 1st bio 1651 * and the 1st bvec in the 2nd bio can be handled in one segment. 1652 */ 1653 static inline bool bios_segs_mergeable(struct request_queue *q, 1654 struct bio *prev, struct bio_vec *prev_last_bv, 1655 struct bio_vec *next_first_bv) 1656 { 1657 if (!BIOVEC_PHYS_MERGEABLE(prev_last_bv, next_first_bv)) 1658 return false; 1659 if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv)) 1660 return false; 1661 if (prev->bi_seg_back_size + next_first_bv->bv_len > 1662 queue_max_segment_size(q)) 1663 return false; 1664 return true; 1665 } 1666 1667 static inline bool bio_will_gap(struct request_queue *q, 1668 struct request *prev_rq, 1669 struct bio *prev, 1670 struct bio *next) 1671 { 1672 if (bio_has_data(prev) && queue_virt_boundary(q)) { 1673 struct bio_vec pb, nb; 1674 1675 /* 1676 * don't merge if the 1st bio starts with non-zero 1677 * offset, otherwise it is quite difficult to respect 1678 * sg gap limit. We work hard to merge a huge number of small 1679 * single bios in case of mkfs. 1680 */ 1681 if (prev_rq) 1682 bio_get_first_bvec(prev_rq->bio, &pb); 1683 else 1684 bio_get_first_bvec(prev, &pb); 1685 if (pb.bv_offset) 1686 return true; 1687 1688 /* 1689 * We don't need to worry about the situation that the 1690 * merged segment ends in unaligned virt boundary: 1691 * 1692 * - if 'pb' ends aligned, the merged segment ends aligned 1693 * - if 'pb' ends unaligned, the next bio must include 1694 * one single bvec of 'nb', otherwise the 'nb' can't 1695 * merge with 'pb' 1696 */ 1697 bio_get_last_bvec(prev, &pb); 1698 bio_get_first_bvec(next, &nb); 1699 1700 if (!bios_segs_mergeable(q, prev, &pb, &nb)) 1701 return __bvec_gap_to_prev(q, &pb, nb.bv_offset); 1702 } 1703 1704 return false; 1705 } 1706 1707 static inline bool req_gap_back_merge(struct request *req, struct bio *bio) 1708 { 1709 return bio_will_gap(req->q, req, req->biotail, bio); 1710 } 1711 1712 static inline bool req_gap_front_merge(struct request *req, struct bio *bio) 1713 { 1714 return bio_will_gap(req->q, NULL, bio, req->bio); 1715 } 1716 1717 int kblockd_schedule_work(struct work_struct *work); 1718 int kblockd_schedule_work_on(int cpu, struct work_struct *work); 1719 int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay); 1720 int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay); 1721 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay); 1722 1723 #ifdef CONFIG_BLK_CGROUP 1724 /* 1725 * This should not be using sched_clock(). A real patch is in progress 1726 * to fix this up, until that is in place we need to disable preemption 1727 * around sched_clock() in this function and set_io_start_time_ns(). 1728 */ 1729 static inline void set_start_time_ns(struct request *req) 1730 { 1731 preempt_disable(); 1732 req->start_time_ns = sched_clock(); 1733 preempt_enable(); 1734 } 1735 1736 static inline void set_io_start_time_ns(struct request *req) 1737 { 1738 preempt_disable(); 1739 req->io_start_time_ns = sched_clock(); 1740 preempt_enable(); 1741 } 1742 1743 static inline uint64_t rq_start_time_ns(struct request *req) 1744 { 1745 return req->start_time_ns; 1746 } 1747 1748 static inline uint64_t rq_io_start_time_ns(struct request *req) 1749 { 1750 return req->io_start_time_ns; 1751 } 1752 #else 1753 static inline void set_start_time_ns(struct request *req) {} 1754 static inline void set_io_start_time_ns(struct request *req) {} 1755 static inline uint64_t rq_start_time_ns(struct request *req) 1756 { 1757 return 0; 1758 } 1759 static inline uint64_t rq_io_start_time_ns(struct request *req) 1760 { 1761 return 0; 1762 } 1763 #endif 1764 1765 #define MODULE_ALIAS_BLOCKDEV(major,minor) \ 1766 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) 1767 #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ 1768 MODULE_ALIAS("block-major-" __stringify(major) "-*") 1769 1770 #if defined(CONFIG_BLK_DEV_INTEGRITY) 1771 1772 enum blk_integrity_flags { 1773 BLK_INTEGRITY_VERIFY = 1 << 0, 1774 BLK_INTEGRITY_GENERATE = 1 << 1, 1775 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2, 1776 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3, 1777 }; 1778 1779 struct blk_integrity_iter { 1780 void *prot_buf; 1781 void *data_buf; 1782 sector_t seed; 1783 unsigned int data_size; 1784 unsigned short interval; 1785 const char *disk_name; 1786 }; 1787 1788 typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *); 1789 1790 struct blk_integrity_profile { 1791 integrity_processing_fn *generate_fn; 1792 integrity_processing_fn *verify_fn; 1793 const char *name; 1794 }; 1795 1796 extern void blk_integrity_register(struct gendisk *, struct blk_integrity *); 1797 extern void blk_integrity_unregister(struct gendisk *); 1798 extern int blk_integrity_compare(struct gendisk *, struct gendisk *); 1799 extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *, 1800 struct scatterlist *); 1801 extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *); 1802 extern bool blk_integrity_merge_rq(struct request_queue *, struct request *, 1803 struct request *); 1804 extern bool blk_integrity_merge_bio(struct request_queue *, struct request *, 1805 struct bio *); 1806 1807 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1808 { 1809 struct blk_integrity *bi = &disk->queue->integrity; 1810 1811 if (!bi->profile) 1812 return NULL; 1813 1814 return bi; 1815 } 1816 1817 static inline 1818 struct blk_integrity *bdev_get_integrity(struct block_device *bdev) 1819 { 1820 return blk_get_integrity(bdev->bd_disk); 1821 } 1822 1823 static inline bool blk_integrity_rq(struct request *rq) 1824 { 1825 return rq->cmd_flags & REQ_INTEGRITY; 1826 } 1827 1828 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1829 unsigned int segs) 1830 { 1831 q->limits.max_integrity_segments = segs; 1832 } 1833 1834 static inline unsigned short 1835 queue_max_integrity_segments(struct request_queue *q) 1836 { 1837 return q->limits.max_integrity_segments; 1838 } 1839 1840 static inline bool integrity_req_gap_back_merge(struct request *req, 1841 struct bio *next) 1842 { 1843 struct bio_integrity_payload *bip = bio_integrity(req->bio); 1844 struct bio_integrity_payload *bip_next = bio_integrity(next); 1845 1846 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1847 bip_next->bip_vec[0].bv_offset); 1848 } 1849 1850 static inline bool integrity_req_gap_front_merge(struct request *req, 1851 struct bio *bio) 1852 { 1853 struct bio_integrity_payload *bip = bio_integrity(bio); 1854 struct bio_integrity_payload *bip_next = bio_integrity(req->bio); 1855 1856 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1], 1857 bip_next->bip_vec[0].bv_offset); 1858 } 1859 1860 #else /* CONFIG_BLK_DEV_INTEGRITY */ 1861 1862 struct bio; 1863 struct block_device; 1864 struct gendisk; 1865 struct blk_integrity; 1866 1867 static inline int blk_integrity_rq(struct request *rq) 1868 { 1869 return 0; 1870 } 1871 static inline int blk_rq_count_integrity_sg(struct request_queue *q, 1872 struct bio *b) 1873 { 1874 return 0; 1875 } 1876 static inline int blk_rq_map_integrity_sg(struct request_queue *q, 1877 struct bio *b, 1878 struct scatterlist *s) 1879 { 1880 return 0; 1881 } 1882 static inline struct blk_integrity *bdev_get_integrity(struct block_device *b) 1883 { 1884 return NULL; 1885 } 1886 static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) 1887 { 1888 return NULL; 1889 } 1890 static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) 1891 { 1892 return 0; 1893 } 1894 static inline void blk_integrity_register(struct gendisk *d, 1895 struct blk_integrity *b) 1896 { 1897 } 1898 static inline void blk_integrity_unregister(struct gendisk *d) 1899 { 1900 } 1901 static inline void blk_queue_max_integrity_segments(struct request_queue *q, 1902 unsigned int segs) 1903 { 1904 } 1905 static inline unsigned short queue_max_integrity_segments(struct request_queue *q) 1906 { 1907 return 0; 1908 } 1909 static inline bool blk_integrity_merge_rq(struct request_queue *rq, 1910 struct request *r1, 1911 struct request *r2) 1912 { 1913 return true; 1914 } 1915 static inline bool blk_integrity_merge_bio(struct request_queue *rq, 1916 struct request *r, 1917 struct bio *b) 1918 { 1919 return true; 1920 } 1921 1922 static inline bool integrity_req_gap_back_merge(struct request *req, 1923 struct bio *next) 1924 { 1925 return false; 1926 } 1927 static inline bool integrity_req_gap_front_merge(struct request *req, 1928 struct bio *bio) 1929 { 1930 return false; 1931 } 1932 1933 #endif /* CONFIG_BLK_DEV_INTEGRITY */ 1934 1935 struct block_device_operations { 1936 int (*open) (struct block_device *, fmode_t); 1937 void (*release) (struct gendisk *, fmode_t); 1938 int (*rw_page)(struct block_device *, sector_t, struct page *, bool); 1939 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1940 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); 1941 unsigned int (*check_events) (struct gendisk *disk, 1942 unsigned int clearing); 1943 /* ->media_changed() is DEPRECATED, use ->check_events() instead */ 1944 int (*media_changed) (struct gendisk *); 1945 void (*unlock_native_capacity) (struct gendisk *); 1946 int (*revalidate_disk) (struct gendisk *); 1947 int (*getgeo)(struct block_device *, struct hd_geometry *); 1948 /* this callback is with swap_lock and sometimes page table lock held */ 1949 void (*swap_slot_free_notify) (struct block_device *, unsigned long); 1950 struct module *owner; 1951 const struct pr_ops *pr_ops; 1952 }; 1953 1954 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, 1955 unsigned long); 1956 extern int bdev_read_page(struct block_device *, sector_t, struct page *); 1957 extern int bdev_write_page(struct block_device *, sector_t, struct page *, 1958 struct writeback_control *); 1959 #else /* CONFIG_BLOCK */ 1960 1961 struct block_device; 1962 1963 /* 1964 * stubs for when the block layer is configured out 1965 */ 1966 #define buffer_heads_over_limit 0 1967 1968 static inline long nr_blockdev_pages(void) 1969 { 1970 return 0; 1971 } 1972 1973 struct blk_plug { 1974 }; 1975 1976 static inline void blk_start_plug(struct blk_plug *plug) 1977 { 1978 } 1979 1980 static inline void blk_finish_plug(struct blk_plug *plug) 1981 { 1982 } 1983 1984 static inline void blk_flush_plug(struct task_struct *task) 1985 { 1986 } 1987 1988 static inline void blk_schedule_flush_plug(struct task_struct *task) 1989 { 1990 } 1991 1992 1993 static inline bool blk_needs_flush_plug(struct task_struct *tsk) 1994 { 1995 return false; 1996 } 1997 1998 static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, 1999 sector_t *error_sector) 2000 { 2001 return 0; 2002 } 2003 2004 #endif /* CONFIG_BLOCK */ 2005 2006 #endif 2007