Line data Source code
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.h>
16 : #include <linux/wait.h>
17 : #include <linux/mempool.h>
18 : #include <linux/bio.h>
19 : #include <linux/stringify.h>
20 : #include <linux/gfp.h>
21 : #include <linux/bsg.h>
22 : #include <linux/smp.h>
23 : #include <linux/rcupdate.h>
24 : #include <linux/percpu-refcount.h>
25 :
26 : #include <asm/scatterlist.h>
27 :
28 : struct module;
29 : struct scsi_ioctl_command;
30 :
31 : struct request_queue;
32 : struct elevator_queue;
33 : struct request_pm_state;
34 : struct blk_trace;
35 : struct request;
36 : struct sg_io_hdr;
37 : struct bsg_job;
38 : struct blkcg_gq;
39 :
40 : #define BLKDEV_MIN_RQ 4
41 : #define BLKDEV_MAX_RQ 128 /* Default maximum */
42 :
43 : /*
44 : * Maximum number of blkcg policies allowed to be registered concurrently.
45 : * Defined here to simplify include dependency.
46 : */
47 : #define BLKCG_MAX_POLS 2
48 :
49 : struct request;
50 : typedef void (rq_end_io_fn)(struct request *, int);
51 :
52 : #define BLK_RL_SYNCFULL (1U << 0)
53 : #define BLK_RL_ASYNCFULL (1U << 1)
54 :
55 : struct request_list {
56 : struct request_queue *q; /* the queue this rl belongs to */
57 : #ifdef CONFIG_BLK_CGROUP
58 : struct blkcg_gq *blkg; /* blkg this request pool belongs to */
59 : #endif
60 : /*
61 : * count[], starved[], and wait[] are indexed by
62 : * BLK_RW_SYNC/BLK_RW_ASYNC
63 : */
64 : int count[2];
65 : int starved[2];
66 : mempool_t *rq_pool;
67 : wait_queue_head_t wait[2];
68 : unsigned int flags;
69 : };
70 :
71 : /*
72 : * request command types
73 : */
74 : enum rq_cmd_type_bits {
75 : REQ_TYPE_FS = 1, /* fs request */
76 : REQ_TYPE_BLOCK_PC, /* scsi command */
77 : REQ_TYPE_SENSE, /* sense request */
78 : REQ_TYPE_PM_SUSPEND, /* suspend request */
79 : REQ_TYPE_PM_RESUME, /* resume request */
80 : REQ_TYPE_PM_SHUTDOWN, /* shutdown request */
81 : REQ_TYPE_SPECIAL, /* driver defined type */
82 : /*
83 : * for ATA/ATAPI devices. this really doesn't belong here, ide should
84 : * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
85 : * private REQ_LB opcodes to differentiate what type of request this is
86 : */
87 : REQ_TYPE_ATA_TASKFILE,
88 : REQ_TYPE_ATA_PC,
89 : };
90 :
91 : #define BLK_MAX_CDB 16
92 :
93 : /*
94 : * Try to put the fields that are referenced together in the same cacheline.
95 : *
96 : * If you modify this structure, make sure to update blk_rq_init() and
97 : * especially blk_mq_rq_ctx_init() to take care of the added fields.
98 : */
99 : struct request {
100 : struct list_head queuelist;
101 : union {
102 : struct call_single_data csd;
103 : unsigned long fifo_time;
104 : };
105 :
106 : struct request_queue *q;
107 : struct blk_mq_ctx *mq_ctx;
108 :
109 : u64 cmd_flags;
110 : enum rq_cmd_type_bits cmd_type;
111 : unsigned long atomic_flags;
112 :
113 : int cpu;
114 :
115 : /* the following two fields are internal, NEVER access directly */
116 : unsigned int __data_len; /* total data len */
117 : sector_t __sector; /* sector cursor */
118 :
119 : struct bio *bio;
120 : struct bio *biotail;
121 :
122 : /*
123 : * The hash is used inside the scheduler, and killed once the
124 : * request reaches the dispatch list. The ipi_list is only used
125 : * to queue the request for softirq completion, which is long
126 : * after the request has been unhashed (and even removed from
127 : * the dispatch list).
128 : */
129 : union {
130 : struct hlist_node hash; /* merge hash */
131 : struct list_head ipi_list;
132 : };
133 :
134 : /*
135 : * The rb_node is only used inside the io scheduler, requests
136 : * are pruned when moved to the dispatch queue. So let the
137 : * completion_data share space with the rb_node.
138 : */
139 : union {
140 : struct rb_node rb_node; /* sort/lookup */
141 : void *completion_data;
142 : };
143 :
144 : /*
145 : * Three pointers are available for the IO schedulers, if they need
146 : * more they have to dynamically allocate it. Flush requests are
147 : * never put on the IO scheduler. So let the flush fields share
148 : * space with the elevator data.
149 : */
150 : union {
151 : struct {
152 : struct io_cq *icq;
153 : void *priv[2];
154 : } elv;
155 :
156 : struct {
157 : unsigned int seq;
158 : struct list_head list;
159 : rq_end_io_fn *saved_end_io;
160 : } flush;
161 : };
162 :
163 : struct gendisk *rq_disk;
164 : struct hd_struct *part;
165 : unsigned long start_time;
166 : #ifdef CONFIG_BLK_CGROUP
167 : struct request_list *rl; /* rl this rq is alloced from */
168 : unsigned long long start_time_ns;
169 : unsigned long long io_start_time_ns; /* when passed to hardware */
170 : #endif
171 : /* Number of scatter-gather DMA addr+len pairs after
172 : * physical address coalescing is performed.
173 : */
174 : unsigned short nr_phys_segments;
175 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
176 : unsigned short nr_integrity_segments;
177 : #endif
178 :
179 : unsigned short ioprio;
180 :
181 : void *special; /* opaque pointer available for LLD use */
182 :
183 : int tag;
184 : int errors;
185 :
186 : /*
187 : * when request is used as a packet command carrier
188 : */
189 : unsigned char __cmd[BLK_MAX_CDB];
190 : unsigned char *cmd;
191 : unsigned short cmd_len;
192 :
193 : unsigned int extra_len; /* length of alignment and padding */
194 : unsigned int sense_len;
195 : unsigned int resid_len; /* residual count */
196 : void *sense;
197 :
198 : unsigned long deadline;
199 : struct list_head timeout_list;
200 : unsigned int timeout;
201 : int retries;
202 :
203 : /*
204 : * completion callback.
205 : */
206 : rq_end_io_fn *end_io;
207 : void *end_io_data;
208 :
209 : /* for bidi */
210 : struct request *next_rq;
211 : };
212 :
213 : static inline unsigned short req_get_ioprio(struct request *req)
214 : {
215 : return req->ioprio;
216 : }
217 :
218 : /*
219 : * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
220 : * requests. Some step values could eventually be made generic.
221 : */
222 : struct request_pm_state
223 : {
224 : /* PM state machine step value, currently driver specific */
225 : int pm_step;
226 : /* requested PM state value (S1, S2, S3, S4, ...) */
227 : u32 pm_state;
228 : void* data; /* for driver use */
229 : };
230 :
231 : #include <linux/elevator.h>
232 :
233 : struct blk_queue_ctx;
234 :
235 : typedef void (request_fn_proc) (struct request_queue *q);
236 : typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
237 : typedef int (prep_rq_fn) (struct request_queue *, struct request *);
238 : typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
239 :
240 : struct bio_vec;
241 : struct bvec_merge_data {
242 : struct block_device *bi_bdev;
243 : sector_t bi_sector;
244 : unsigned bi_size;
245 : unsigned long bi_rw;
246 : };
247 : typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
248 : struct bio_vec *);
249 : typedef void (softirq_done_fn)(struct request *);
250 : typedef int (dma_drain_needed_fn)(struct request *);
251 : typedef int (lld_busy_fn) (struct request_queue *q);
252 : typedef int (bsg_job_fn) (struct bsg_job *);
253 :
254 : enum blk_eh_timer_return {
255 : BLK_EH_NOT_HANDLED,
256 : BLK_EH_HANDLED,
257 : BLK_EH_RESET_TIMER,
258 : };
259 :
260 : typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
261 :
262 : enum blk_queue_state {
263 : Queue_down,
264 : Queue_up,
265 : };
266 :
267 : struct blk_queue_tag {
268 : struct request **tag_index; /* map of busy tags */
269 : unsigned long *tag_map; /* bit map of free/busy tags */
270 : int busy; /* current depth */
271 : int max_depth; /* what we will send to device */
272 : int real_max_depth; /* what the array can hold */
273 : atomic_t refcnt; /* map can be shared */
274 : };
275 :
276 : #define BLK_SCSI_MAX_CMDS (256)
277 : #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
278 :
279 : struct queue_limits {
280 : unsigned long bounce_pfn;
281 : unsigned long seg_boundary_mask;
282 :
283 : unsigned int max_hw_sectors;
284 : unsigned int chunk_sectors;
285 : unsigned int max_sectors;
286 : unsigned int max_segment_size;
287 : unsigned int physical_block_size;
288 : unsigned int alignment_offset;
289 : unsigned int io_min;
290 : unsigned int io_opt;
291 : unsigned int max_discard_sectors;
292 : unsigned int max_write_same_sectors;
293 : unsigned int discard_granularity;
294 : unsigned int discard_alignment;
295 :
296 : unsigned short logical_block_size;
297 : unsigned short max_segments;
298 : unsigned short max_integrity_segments;
299 :
300 : unsigned char misaligned;
301 : unsigned char discard_misaligned;
302 : unsigned char cluster;
303 : unsigned char discard_zeroes_data;
304 : unsigned char raid_partial_stripes_expensive;
305 : };
306 :
307 : struct request_queue {
308 : /*
309 : * Together with queue_head for cacheline sharing
310 : */
311 : struct list_head queue_head;
312 : struct request *last_merge;
313 : struct elevator_queue *elevator;
314 : int nr_rqs[2]; /* # allocated [a]sync rqs */
315 : int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
316 :
317 : /*
318 : * If blkcg is not used, @q->root_rl serves all requests. If blkcg
319 : * is used, root blkg allocates from @q->root_rl and all other
320 : * blkgs from their own blkg->rl. Which one to use should be
321 : * determined using bio_request_list().
322 : */
323 : struct request_list root_rl;
324 :
325 : request_fn_proc *request_fn;
326 : make_request_fn *make_request_fn;
327 : prep_rq_fn *prep_rq_fn;
328 : unprep_rq_fn *unprep_rq_fn;
329 : merge_bvec_fn *merge_bvec_fn;
330 : softirq_done_fn *softirq_done_fn;
331 : rq_timed_out_fn *rq_timed_out_fn;
332 : dma_drain_needed_fn *dma_drain_needed;
333 : lld_busy_fn *lld_busy_fn;
334 :
335 : struct blk_mq_ops *mq_ops;
336 :
337 : unsigned int *mq_map;
338 :
339 : /* sw queues */
340 : struct blk_mq_ctx __percpu *queue_ctx;
341 : unsigned int nr_queues;
342 :
343 : /* hw dispatch queues */
344 : struct blk_mq_hw_ctx **queue_hw_ctx;
345 : unsigned int nr_hw_queues;
346 :
347 : /*
348 : * Dispatch queue sorting
349 : */
350 : sector_t end_sector;
351 : struct request *boundary_rq;
352 :
353 : /*
354 : * Delayed queue handling
355 : */
356 : struct delayed_work delay_work;
357 :
358 : struct backing_dev_info backing_dev_info;
359 :
360 : /*
361 : * The queue owner gets to use this for whatever they like.
362 : * ll_rw_blk doesn't touch it.
363 : */
364 : void *queuedata;
365 :
366 : /*
367 : * various queue flags, see QUEUE_* below
368 : */
369 : unsigned long queue_flags;
370 :
371 : /*
372 : * ida allocated id for this queue. Used to index queues from
373 : * ioctx.
374 : */
375 : int id;
376 :
377 : /*
378 : * queue needs bounce pages for pages above this limit
379 : */
380 : gfp_t bounce_gfp;
381 :
382 : /*
383 : * protects queue structures from reentrancy. ->__queue_lock should
384 : * _never_ be used directly, it is queue private. always use
385 : * ->queue_lock.
386 : */
387 : spinlock_t __queue_lock;
388 : spinlock_t *queue_lock;
389 :
390 : /*
391 : * queue kobject
392 : */
393 : struct kobject kobj;
394 :
395 : /*
396 : * mq queue kobject
397 : */
398 : struct kobject mq_kobj;
399 :
400 : #ifdef CONFIG_PM_RUNTIME
401 : struct device *dev;
402 : int rpm_status;
403 : unsigned int nr_pending;
404 : #endif
405 :
406 : /*
407 : * queue settings
408 : */
409 : unsigned long nr_requests; /* Max # of requests */
410 : unsigned int nr_congestion_on;
411 : unsigned int nr_congestion_off;
412 : unsigned int nr_batching;
413 :
414 : unsigned int dma_drain_size;
415 : void *dma_drain_buffer;
416 : unsigned int dma_pad_mask;
417 : unsigned int dma_alignment;
418 :
419 : struct blk_queue_tag *queue_tags;
420 : struct list_head tag_busy_list;
421 :
422 : unsigned int nr_sorted;
423 : unsigned int in_flight[2];
424 : /*
425 : * Number of active block driver functions for which blk_drain_queue()
426 : * must wait. Must be incremented around functions that unlock the
427 : * queue_lock internally, e.g. scsi_request_fn().
428 : */
429 : unsigned int request_fn_active;
430 :
431 : unsigned int rq_timeout;
432 : struct timer_list timeout;
433 : struct list_head timeout_list;
434 :
435 : struct list_head icq_list;
436 : #ifdef CONFIG_BLK_CGROUP
437 : DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
438 : struct blkcg_gq *root_blkg;
439 : struct list_head blkg_list;
440 : #endif
441 :
442 : struct queue_limits limits;
443 :
444 : /*
445 : * sg stuff
446 : */
447 : unsigned int sg_timeout;
448 : unsigned int sg_reserved_size;
449 : int node;
450 : #ifdef CONFIG_BLK_DEV_IO_TRACE
451 : struct blk_trace *blk_trace;
452 : #endif
453 : /*
454 : * for flush operations
455 : */
456 : unsigned int flush_flags;
457 : unsigned int flush_not_queueable:1;
458 : unsigned int flush_queue_delayed:1;
459 : unsigned int flush_pending_idx:1;
460 : unsigned int flush_running_idx:1;
461 : unsigned long flush_pending_since;
462 : struct list_head flush_queue[2];
463 : struct list_head flush_data_in_flight;
464 : struct request *flush_rq;
465 : spinlock_t mq_flush_lock;
466 :
467 : struct list_head requeue_list;
468 : spinlock_t requeue_lock;
469 : struct work_struct requeue_work;
470 :
471 : struct mutex sysfs_lock;
472 :
473 : int bypass_depth;
474 : int mq_freeze_depth;
475 :
476 : #if defined(CONFIG_BLK_DEV_BSG)
477 : bsg_job_fn *bsg_job_fn;
478 : int bsg_job_size;
479 : struct bsg_class_device bsg_dev;
480 : #endif
481 :
482 : #ifdef CONFIG_BLK_DEV_THROTTLING
483 : /* Throttle data */
484 : struct throtl_data *td;
485 : #endif
486 : struct rcu_head rcu_head;
487 : wait_queue_head_t mq_freeze_wq;
488 : struct percpu_ref mq_usage_counter;
489 : struct list_head all_q_node;
490 :
491 : struct blk_mq_tag_set *tag_set;
492 : struct list_head tag_set_list;
493 : };
494 :
495 : #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
496 : #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
497 : #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
498 : #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
499 : #define QUEUE_FLAG_DYING 5 /* queue being torn down */
500 : #define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
501 : #define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
502 : #define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
503 : #define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
504 : #define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
505 : #define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
506 : #define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
507 : #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
508 : #define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
509 : #define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
510 : #define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
511 : #define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
512 : #define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
513 : #define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
514 : #define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
515 : #define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
516 : #define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
517 : #define QUEUE_FLAG_SG_GAPS 22 /* queue doesn't support SG gaps */
518 :
519 : #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
520 : (1 << QUEUE_FLAG_STACKABLE) | \
521 : (1 << QUEUE_FLAG_SAME_COMP) | \
522 : (1 << QUEUE_FLAG_ADD_RANDOM))
523 :
524 : #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
525 : (1 << QUEUE_FLAG_SAME_COMP))
526 :
527 : static inline void queue_lockdep_assert_held(struct request_queue *q)
528 : {
529 : if (q->queue_lock)
530 : lockdep_assert_held(q->queue_lock);
531 : }
532 :
533 : static inline void queue_flag_set_unlocked(unsigned int flag,
534 : struct request_queue *q)
535 : {
536 : __set_bit(flag, &q->queue_flags);
537 : }
538 :
539 : static inline int queue_flag_test_and_clear(unsigned int flag,
540 : struct request_queue *q)
541 : {
542 : queue_lockdep_assert_held(q);
543 :
544 : if (test_bit(flag, &q->queue_flags)) {
545 : __clear_bit(flag, &q->queue_flags);
546 : return 1;
547 : }
548 :
549 : return 0;
550 : }
551 :
552 : static inline int queue_flag_test_and_set(unsigned int flag,
553 : struct request_queue *q)
554 : {
555 : queue_lockdep_assert_held(q);
556 :
557 : if (!test_bit(flag, &q->queue_flags)) {
558 : __set_bit(flag, &q->queue_flags);
559 : return 0;
560 : }
561 :
562 : return 1;
563 : }
564 :
565 : static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
566 : {
567 : queue_lockdep_assert_held(q);
568 : __set_bit(flag, &q->queue_flags);
569 : }
570 :
571 : static inline void queue_flag_clear_unlocked(unsigned int flag,
572 : struct request_queue *q)
573 : {
574 : __clear_bit(flag, &q->queue_flags);
575 : }
576 :
577 : static inline int queue_in_flight(struct request_queue *q)
578 : {
579 : return q->in_flight[0] + q->in_flight[1];
580 : }
581 :
582 : static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
583 : {
584 : queue_lockdep_assert_held(q);
585 : __clear_bit(flag, &q->queue_flags);
586 : }
587 :
588 : #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
589 : #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
590 : #define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
591 : #define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
592 : #define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
593 : #define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
594 : #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
595 : #define blk_queue_noxmerges(q) \
596 : test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
597 : #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
598 : #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
599 : #define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
600 : #define blk_queue_stackable(q) \
601 : test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
602 : #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
603 : #define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
604 : test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
605 :
606 : #define blk_noretry_request(rq) \
607 : ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
608 : REQ_FAILFAST_DRIVER))
609 :
610 : #define blk_account_rq(rq) \
611 : (((rq)->cmd_flags & REQ_STARTED) && \
612 : ((rq)->cmd_type == REQ_TYPE_FS))
613 :
614 : #define blk_pm_request(rq) \
615 : ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
616 : (rq)->cmd_type == REQ_TYPE_PM_RESUME)
617 :
618 : #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
619 : #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
620 : /* rq->queuelist of dequeued request must be list_empty() */
621 : #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
622 :
623 : #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
624 :
625 : #define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
626 :
627 : /*
628 : * Driver can handle struct request, if it either has an old style
629 : * request_fn defined, or is blk-mq based.
630 : */
631 : static inline bool queue_is_rq_based(struct request_queue *q)
632 : {
633 : return q->request_fn || q->mq_ops;
634 : }
635 :
636 : static inline unsigned int blk_queue_cluster(struct request_queue *q)
637 : {
638 : return q->limits.cluster;
639 : }
640 :
641 : /*
642 : * We regard a request as sync, if either a read or a sync write
643 : */
644 : static inline bool rw_is_sync(unsigned int rw_flags)
645 : {
646 : return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
647 : }
648 :
649 : static inline bool rq_is_sync(struct request *rq)
650 : {
651 : return rw_is_sync(rq->cmd_flags);
652 : }
653 :
654 : static inline bool blk_rl_full(struct request_list *rl, bool sync)
655 : {
656 : unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
657 :
658 : return rl->flags & flag;
659 : }
660 :
661 : static inline void blk_set_rl_full(struct request_list *rl, bool sync)
662 : {
663 : unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
664 :
665 : rl->flags |= flag;
666 : }
667 :
668 : static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
669 : {
670 : unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
671 :
672 : rl->flags &= ~flag;
673 : }
674 :
675 : static inline bool rq_mergeable(struct request *rq)
676 : {
677 : if (rq->cmd_type != REQ_TYPE_FS)
678 : return false;
679 :
680 : if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
681 : return false;
682 :
683 : return true;
684 : }
685 :
686 : static inline bool blk_check_merge_flags(unsigned int flags1,
687 : unsigned int flags2)
688 : {
689 : if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
690 : return false;
691 :
692 : if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
693 : return false;
694 :
695 : if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
696 : return false;
697 :
698 : return true;
699 : }
700 :
701 : static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
702 : {
703 : if (bio_data(a) == bio_data(b))
704 : return true;
705 :
706 : return false;
707 : }
708 :
709 : /*
710 : * q->prep_rq_fn return values
711 : */
712 : #define BLKPREP_OK 0 /* serve it */
713 : #define BLKPREP_KILL 1 /* fatal error, kill */
714 : #define BLKPREP_DEFER 2 /* leave on queue */
715 :
716 : extern unsigned long blk_max_low_pfn, blk_max_pfn;
717 :
718 : /*
719 : * standard bounce addresses:
720 : *
721 : * BLK_BOUNCE_HIGH : bounce all highmem pages
722 : * BLK_BOUNCE_ANY : don't bounce anything
723 : * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
724 : */
725 :
726 : #if BITS_PER_LONG == 32
727 : #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
728 : #else
729 : #define BLK_BOUNCE_HIGH -1ULL
730 : #endif
731 : #define BLK_BOUNCE_ANY (-1ULL)
732 : #define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
733 :
734 : /*
735 : * default timeout for SG_IO if none specified
736 : */
737 : #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
738 : #define BLK_MIN_SG_TIMEOUT (7 * HZ)
739 :
740 : #ifdef CONFIG_BOUNCE
741 : extern int init_emergency_isa_pool(void);
742 : extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
743 : #else
744 : static inline int init_emergency_isa_pool(void)
745 : {
746 : return 0;
747 : }
748 : static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
749 : {
750 : }
751 : #endif /* CONFIG_MMU */
752 :
753 : struct rq_map_data {
754 : struct page **pages;
755 : int page_order;
756 : int nr_entries;
757 : unsigned long offset;
758 : int null_mapped;
759 : int from_user;
760 : };
761 :
762 : struct req_iterator {
763 : struct bvec_iter iter;
764 : struct bio *bio;
765 : };
766 :
767 : /* This should not be used directly - use rq_for_each_segment */
768 : #define for_each_bio(_bio) \
769 : for (; _bio; _bio = _bio->bi_next)
770 : #define __rq_for_each_bio(_bio, rq) \
771 : if ((rq->bio)) \
772 : for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
773 :
774 : #define rq_for_each_segment(bvl, _rq, _iter) \
775 : __rq_for_each_bio(_iter.bio, _rq) \
776 : bio_for_each_segment(bvl, _iter.bio, _iter.iter)
777 :
778 : #define rq_iter_last(bvec, _iter) \
779 : (_iter.bio->bi_next == NULL && \
780 : bio_iter_last(bvec, _iter.iter))
781 :
782 : #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
783 : # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
784 : #endif
785 : #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
786 : extern void rq_flush_dcache_pages(struct request *rq);
787 : #else
788 : static inline void rq_flush_dcache_pages(struct request *rq)
789 : {
790 : }
791 : #endif
792 :
793 : extern int blk_register_queue(struct gendisk *disk);
794 : extern void blk_unregister_queue(struct gendisk *disk);
795 : extern void generic_make_request(struct bio *bio);
796 : extern void blk_rq_init(struct request_queue *q, struct request *rq);
797 : extern void blk_put_request(struct request *);
798 : extern void __blk_put_request(struct request_queue *, struct request *);
799 : extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
800 : extern struct request *blk_make_request(struct request_queue *, struct bio *,
801 : gfp_t);
802 : extern void blk_rq_set_block_pc(struct request *);
803 : extern void blk_requeue_request(struct request_queue *, struct request *);
804 : extern void blk_add_request_payload(struct request *rq, struct page *page,
805 : unsigned int len);
806 : extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
807 : extern int blk_lld_busy(struct request_queue *q);
808 : extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
809 : struct bio_set *bs, gfp_t gfp_mask,
810 : int (*bio_ctr)(struct bio *, struct bio *, void *),
811 : void *data);
812 : extern void blk_rq_unprep_clone(struct request *rq);
813 : extern int blk_insert_cloned_request(struct request_queue *q,
814 : struct request *rq);
815 : extern void blk_delay_queue(struct request_queue *, unsigned long);
816 : extern void blk_recount_segments(struct request_queue *, struct bio *);
817 : extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
818 : extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
819 : unsigned int, void __user *);
820 : extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
821 : unsigned int, void __user *);
822 : extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
823 : struct scsi_ioctl_command __user *);
824 :
825 : extern void blk_queue_bio(struct request_queue *q, struct bio *bio);
826 :
827 : /*
828 : * A queue has just exitted congestion. Note this in the global counter of
829 : * congested queues, and wake up anyone who was waiting for requests to be
830 : * put back.
831 : */
832 : static inline void blk_clear_queue_congested(struct request_queue *q, int sync)
833 : {
834 : clear_bdi_congested(&q->backing_dev_info, sync);
835 : }
836 :
837 : /*
838 : * A queue has just entered congestion. Flag that in the queue's VM-visible
839 : * state flags and increment the global gounter of congested queues.
840 : */
841 : static inline void blk_set_queue_congested(struct request_queue *q, int sync)
842 : {
843 : set_bdi_congested(&q->backing_dev_info, sync);
844 : }
845 :
846 : extern void blk_start_queue(struct request_queue *q);
847 : extern void blk_stop_queue(struct request_queue *q);
848 : extern void blk_sync_queue(struct request_queue *q);
849 : extern void __blk_stop_queue(struct request_queue *q);
850 : extern void __blk_run_queue(struct request_queue *q);
851 : extern void blk_run_queue(struct request_queue *);
852 : extern void blk_run_queue_async(struct request_queue *q);
853 : extern int blk_rq_map_user(struct request_queue *, struct request *,
854 : struct rq_map_data *, void __user *, unsigned long,
855 : gfp_t);
856 : extern int blk_rq_unmap_user(struct bio *);
857 : extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
858 : extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
859 : struct rq_map_data *, const struct sg_iovec *,
860 : int, unsigned int, gfp_t);
861 : extern int blk_execute_rq(struct request_queue *, struct gendisk *,
862 : struct request *, int);
863 : extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
864 : struct request *, int, rq_end_io_fn *);
865 :
866 : static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
867 : {
868 213418 : return bdev->bd_disk->queue;
869 : }
870 :
871 : /*
872 : * blk_rq_pos() : the current sector
873 : * blk_rq_bytes() : bytes left in the entire request
874 : * blk_rq_cur_bytes() : bytes left in the current segment
875 : * blk_rq_err_bytes() : bytes left till the next error boundary
876 : * blk_rq_sectors() : sectors left in the entire request
877 : * blk_rq_cur_sectors() : sectors left in the current segment
878 : */
879 : static inline sector_t blk_rq_pos(const struct request *rq)
880 : {
881 : return rq->__sector;
882 : }
883 :
884 : static inline unsigned int blk_rq_bytes(const struct request *rq)
885 : {
886 : return rq->__data_len;
887 : }
888 :
889 : static inline int blk_rq_cur_bytes(const struct request *rq)
890 : {
891 : return rq->bio ? bio_cur_bytes(rq->bio) : 0;
892 : }
893 :
894 : extern unsigned int blk_rq_err_bytes(const struct request *rq);
895 :
896 : static inline unsigned int blk_rq_sectors(const struct request *rq)
897 : {
898 : return blk_rq_bytes(rq) >> 9;
899 : }
900 :
901 : static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
902 : {
903 : return blk_rq_cur_bytes(rq) >> 9;
904 : }
905 :
906 : static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
907 : unsigned int cmd_flags)
908 : {
909 : if (unlikely(cmd_flags & REQ_DISCARD))
910 : return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
911 :
912 : if (unlikely(cmd_flags & REQ_WRITE_SAME))
913 : return q->limits.max_write_same_sectors;
914 :
915 : return q->limits.max_sectors;
916 : }
917 :
918 : /*
919 : * Return maximum size of a request at given offset. Only valid for
920 : * file system requests.
921 : */
922 : static inline unsigned int blk_max_size_offset(struct request_queue *q,
923 : sector_t offset)
924 : {
925 : if (!q->limits.chunk_sectors)
926 : return q->limits.max_sectors;
927 :
928 : return q->limits.chunk_sectors -
929 : (offset & (q->limits.chunk_sectors - 1));
930 : }
931 :
932 : static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
933 : {
934 : struct request_queue *q = rq->q;
935 :
936 : if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
937 : return q->limits.max_hw_sectors;
938 :
939 : if (!q->limits.chunk_sectors)
940 : return blk_queue_get_max_sectors(q, rq->cmd_flags);
941 :
942 : return min(blk_max_size_offset(q, blk_rq_pos(rq)),
943 : blk_queue_get_max_sectors(q, rq->cmd_flags));
944 : }
945 :
946 : static inline unsigned int blk_rq_count_bios(struct request *rq)
947 : {
948 : unsigned int nr_bios = 0;
949 : struct bio *bio;
950 :
951 : __rq_for_each_bio(bio, rq)
952 : nr_bios++;
953 :
954 : return nr_bios;
955 : }
956 :
957 : /*
958 : * Request issue related functions.
959 : */
960 : extern struct request *blk_peek_request(struct request_queue *q);
961 : extern void blk_start_request(struct request *rq);
962 : extern struct request *blk_fetch_request(struct request_queue *q);
963 :
964 : /*
965 : * Request completion related functions.
966 : *
967 : * blk_update_request() completes given number of bytes and updates
968 : * the request without completing it.
969 : *
970 : * blk_end_request() and friends. __blk_end_request() must be called
971 : * with the request queue spinlock acquired.
972 : *
973 : * Several drivers define their own end_request and call
974 : * blk_end_request() for parts of the original function.
975 : * This prevents code duplication in drivers.
976 : */
977 : extern bool blk_update_request(struct request *rq, int error,
978 : unsigned int nr_bytes);
979 : extern void blk_finish_request(struct request *rq, int error);
980 : extern bool blk_end_request(struct request *rq, int error,
981 : unsigned int nr_bytes);
982 : extern void blk_end_request_all(struct request *rq, int error);
983 : extern bool blk_end_request_cur(struct request *rq, int error);
984 : extern bool blk_end_request_err(struct request *rq, int error);
985 : extern bool __blk_end_request(struct request *rq, int error,
986 : unsigned int nr_bytes);
987 : extern void __blk_end_request_all(struct request *rq, int error);
988 : extern bool __blk_end_request_cur(struct request *rq, int error);
989 : extern bool __blk_end_request_err(struct request *rq, int error);
990 :
991 : extern void blk_complete_request(struct request *);
992 : extern void __blk_complete_request(struct request *);
993 : extern void blk_abort_request(struct request *);
994 : extern void blk_unprep_request(struct request *);
995 :
996 : /*
997 : * Access functions for manipulating queue properties
998 : */
999 : extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
1000 : spinlock_t *lock, int node_id);
1001 : extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
1002 : extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
1003 : request_fn_proc *, spinlock_t *);
1004 : extern void blk_cleanup_queue(struct request_queue *);
1005 : extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1006 : extern void blk_queue_bounce_limit(struct request_queue *, u64);
1007 : extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
1008 : extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
1009 : extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
1010 : extern void blk_queue_max_segments(struct request_queue *, unsigned short);
1011 : extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
1012 : extern void blk_queue_max_discard_sectors(struct request_queue *q,
1013 : unsigned int max_discard_sectors);
1014 : extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1015 : unsigned int max_write_same_sectors);
1016 : extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
1017 : extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
1018 : extern void blk_queue_alignment_offset(struct request_queue *q,
1019 : unsigned int alignment);
1020 : extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
1021 : extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
1022 : extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
1023 : extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
1024 : extern void blk_set_default_limits(struct queue_limits *lim);
1025 : extern void blk_set_stacking_limits(struct queue_limits *lim);
1026 : extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1027 : sector_t offset);
1028 : extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1029 : sector_t offset);
1030 : extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1031 : sector_t offset);
1032 : extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
1033 : extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
1034 : extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
1035 : extern int blk_queue_dma_drain(struct request_queue *q,
1036 : dma_drain_needed_fn *dma_drain_needed,
1037 : void *buf, unsigned int size);
1038 : extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
1039 : extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1040 : extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
1041 : extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
1042 : extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
1043 : extern void blk_queue_dma_alignment(struct request_queue *, int);
1044 : extern void blk_queue_update_dma_alignment(struct request_queue *, int);
1045 : extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
1046 : extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1047 : extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
1048 : extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
1049 : extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
1050 : extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
1051 :
1052 : extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
1053 : extern int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
1054 : struct scatterlist *sglist);
1055 : extern void blk_dump_rq_flags(struct request *, char *);
1056 : extern long nr_blockdev_pages(void);
1057 :
1058 : bool __must_check blk_get_queue(struct request_queue *);
1059 : struct request_queue *blk_alloc_queue(gfp_t);
1060 : struct request_queue *blk_alloc_queue_node(gfp_t, int);
1061 : extern void blk_put_queue(struct request_queue *);
1062 :
1063 : /*
1064 : * block layer runtime pm functions
1065 : */
1066 : #ifdef CONFIG_PM_RUNTIME
1067 : extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1068 : extern int blk_pre_runtime_suspend(struct request_queue *q);
1069 : extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1070 : extern void blk_pre_runtime_resume(struct request_queue *q);
1071 : extern void blk_post_runtime_resume(struct request_queue *q, int err);
1072 : #else
1073 : static inline void blk_pm_runtime_init(struct request_queue *q,
1074 : struct device *dev) {}
1075 : static inline int blk_pre_runtime_suspend(struct request_queue *q)
1076 : {
1077 : return -ENOSYS;
1078 : }
1079 : static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1080 : static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1081 : static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1082 : #endif
1083 :
1084 : /*
1085 : * blk_plug permits building a queue of related requests by holding the I/O
1086 : * fragments for a short period. This allows merging of sequential requests
1087 : * into single larger request. As the requests are moved from a per-task list to
1088 : * the device's request_queue in a batch, this results in improved scalability
1089 : * as the lock contention for request_queue lock is reduced.
1090 : *
1091 : * It is ok not to disable preemption when adding the request to the plug list
1092 : * or when attempting a merge, because blk_schedule_flush_list() will only flush
1093 : * the plug list when the task sleeps by itself. For details, please see
1094 : * schedule() where blk_schedule_flush_plug() is called.
1095 : */
1096 : struct blk_plug {
1097 : struct list_head list; /* requests */
1098 : struct list_head mq_list; /* blk-mq requests */
1099 : struct list_head cb_list; /* md requires an unplug callback */
1100 : };
1101 : #define BLK_MAX_REQUEST_COUNT 16
1102 :
1103 : struct blk_plug_cb;
1104 : typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
1105 : struct blk_plug_cb {
1106 : struct list_head list;
1107 : blk_plug_cb_fn callback;
1108 : void *data;
1109 : };
1110 : extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1111 : void *data, int size);
1112 : extern void blk_start_plug(struct blk_plug *);
1113 : extern void blk_finish_plug(struct blk_plug *);
1114 : extern void blk_flush_plug_list(struct blk_plug *, bool);
1115 :
1116 : static inline void blk_flush_plug(struct task_struct *tsk)
1117 : {
1118 : struct blk_plug *plug = tsk->plug;
1119 :
1120 : if (plug)
1121 : blk_flush_plug_list(plug, false);
1122 : }
1123 :
1124 : static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1125 : {
1126 : struct blk_plug *plug = tsk->plug;
1127 :
1128 : if (plug)
1129 : blk_flush_plug_list(plug, true);
1130 : }
1131 :
1132 : static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1133 : {
1134 : struct blk_plug *plug = tsk->plug;
1135 :
1136 : return plug &&
1137 : (!list_empty(&plug->list) ||
1138 : !list_empty(&plug->mq_list) ||
1139 : !list_empty(&plug->cb_list));
1140 : }
1141 :
1142 : /*
1143 : * tag stuff
1144 : */
1145 : #define blk_rq_tagged(rq) \
1146 : ((rq)->mq_ctx || ((rq)->cmd_flags & REQ_QUEUED))
1147 : extern int blk_queue_start_tag(struct request_queue *, struct request *);
1148 : extern struct request *blk_queue_find_tag(struct request_queue *, int);
1149 : extern void blk_queue_end_tag(struct request_queue *, struct request *);
1150 : extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
1151 : extern void blk_queue_free_tags(struct request_queue *);
1152 : extern int blk_queue_resize_tags(struct request_queue *, int);
1153 : extern void blk_queue_invalidate_tags(struct request_queue *);
1154 : extern struct blk_queue_tag *blk_init_tags(int);
1155 : extern void blk_free_tags(struct blk_queue_tag *);
1156 :
1157 : static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1158 : int tag)
1159 : {
1160 : if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1161 : return NULL;
1162 : return bqt->tag_index[tag];
1163 : }
1164 :
1165 : #define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1166 :
1167 : extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
1168 : extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1169 : sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
1170 : extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1171 : sector_t nr_sects, gfp_t gfp_mask, struct page *page);
1172 : extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
1173 : sector_t nr_sects, gfp_t gfp_mask);
1174 : static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1175 : sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
1176 : {
1177 : return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1178 : nr_blocks << (sb->s_blocksize_bits - 9),
1179 : gfp_mask, flags);
1180 : }
1181 : static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
1182 : sector_t nr_blocks, gfp_t gfp_mask)
1183 : {
1184 : return blkdev_issue_zeroout(sb->s_bdev,
1185 : block << (sb->s_blocksize_bits - 9),
1186 : nr_blocks << (sb->s_blocksize_bits - 9),
1187 : gfp_mask);
1188 : }
1189 :
1190 : extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1191 :
1192 : enum blk_default_limits {
1193 : BLK_MAX_SEGMENTS = 128,
1194 : BLK_SAFE_MAX_SECTORS = 255,
1195 : BLK_DEF_MAX_SECTORS = 1024,
1196 : BLK_MAX_SEGMENT_SIZE = 65536,
1197 : BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1198 : };
1199 :
1200 : #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1201 :
1202 : static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1203 : {
1204 : return q->limits.bounce_pfn;
1205 : }
1206 :
1207 : static inline unsigned long queue_segment_boundary(struct request_queue *q)
1208 : {
1209 : return q->limits.seg_boundary_mask;
1210 : }
1211 :
1212 : static inline unsigned int queue_max_sectors(struct request_queue *q)
1213 : {
1214 : return q->limits.max_sectors;
1215 : }
1216 :
1217 : static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1218 : {
1219 : return q->limits.max_hw_sectors;
1220 : }
1221 :
1222 : static inline unsigned short queue_max_segments(struct request_queue *q)
1223 : {
1224 : return q->limits.max_segments;
1225 : }
1226 :
1227 : static inline unsigned int queue_max_segment_size(struct request_queue *q)
1228 : {
1229 : return q->limits.max_segment_size;
1230 : }
1231 :
1232 : static inline unsigned short queue_logical_block_size(struct request_queue *q)
1233 : {
1234 : int retval = 512;
1235 :
1236 : if (q && q->limits.logical_block_size)
1237 : retval = q->limits.logical_block_size;
1238 :
1239 : return retval;
1240 : }
1241 :
1242 : static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
1243 : {
1244 : return queue_logical_block_size(bdev_get_queue(bdev));
1245 : }
1246 :
1247 : static inline unsigned int queue_physical_block_size(struct request_queue *q)
1248 : {
1249 : return q->limits.physical_block_size;
1250 : }
1251 :
1252 : static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
1253 : {
1254 : return queue_physical_block_size(bdev_get_queue(bdev));
1255 : }
1256 :
1257 : static inline unsigned int queue_io_min(struct request_queue *q)
1258 : {
1259 : return q->limits.io_min;
1260 : }
1261 :
1262 : static inline int bdev_io_min(struct block_device *bdev)
1263 : {
1264 : return queue_io_min(bdev_get_queue(bdev));
1265 : }
1266 :
1267 : static inline unsigned int queue_io_opt(struct request_queue *q)
1268 : {
1269 : return q->limits.io_opt;
1270 : }
1271 :
1272 : static inline int bdev_io_opt(struct block_device *bdev)
1273 : {
1274 : return queue_io_opt(bdev_get_queue(bdev));
1275 : }
1276 :
1277 : static inline int queue_alignment_offset(struct request_queue *q)
1278 : {
1279 : if (q->limits.misaligned)
1280 : return -1;
1281 :
1282 : return q->limits.alignment_offset;
1283 : }
1284 :
1285 : static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
1286 : {
1287 : unsigned int granularity = max(lim->physical_block_size, lim->io_min);
1288 : unsigned int alignment = (sector << 9) & (granularity - 1);
1289 :
1290 : return (granularity + lim->alignment_offset - alignment)
1291 : & (granularity - 1);
1292 : }
1293 :
1294 : static inline int bdev_alignment_offset(struct block_device *bdev)
1295 : {
1296 : struct request_queue *q = bdev_get_queue(bdev);
1297 :
1298 : if (q->limits.misaligned)
1299 : return -1;
1300 :
1301 : if (bdev != bdev->bd_contains)
1302 : return bdev->bd_part->alignment_offset;
1303 :
1304 : return q->limits.alignment_offset;
1305 : }
1306 :
1307 : static inline int queue_discard_alignment(struct request_queue *q)
1308 : {
1309 : if (q->limits.discard_misaligned)
1310 : return -1;
1311 :
1312 : return q->limits.discard_alignment;
1313 : }
1314 :
1315 : static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
1316 : {
1317 : unsigned int alignment, granularity, offset;
1318 :
1319 : if (!lim->max_discard_sectors)
1320 : return 0;
1321 :
1322 : /* Why are these in bytes, not sectors? */
1323 : alignment = lim->discard_alignment >> 9;
1324 : granularity = lim->discard_granularity >> 9;
1325 : if (!granularity)
1326 : return 0;
1327 :
1328 : /* Offset of the partition start in 'granularity' sectors */
1329 : offset = sector_div(sector, granularity);
1330 :
1331 : /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1332 : offset = (granularity + alignment - offset) % granularity;
1333 :
1334 : /* Turn it back into bytes, gaah */
1335 : return offset << 9;
1336 : }
1337 :
1338 : static inline int bdev_discard_alignment(struct block_device *bdev)
1339 : {
1340 : struct request_queue *q = bdev_get_queue(bdev);
1341 :
1342 : if (bdev != bdev->bd_contains)
1343 : return bdev->bd_part->discard_alignment;
1344 :
1345 : return q->limits.discard_alignment;
1346 : }
1347 :
1348 : static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1349 : {
1350 : if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
1351 : return 1;
1352 :
1353 : return 0;
1354 : }
1355 :
1356 : static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1357 : {
1358 : return queue_discard_zeroes_data(bdev_get_queue(bdev));
1359 : }
1360 :
1361 : static inline unsigned int bdev_write_same(struct block_device *bdev)
1362 : {
1363 : struct request_queue *q = bdev_get_queue(bdev);
1364 :
1365 : if (q)
1366 : return q->limits.max_write_same_sectors;
1367 :
1368 : return 0;
1369 : }
1370 :
1371 : static inline int queue_dma_alignment(struct request_queue *q)
1372 : {
1373 : return q ? q->dma_alignment : 511;
1374 : }
1375 :
1376 : static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
1377 : unsigned int len)
1378 : {
1379 : unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
1380 : return !(addr & alignment) && !(len & alignment);
1381 : }
1382 :
1383 : /* assumes size > 256 */
1384 : static inline unsigned int blksize_bits(unsigned int size)
1385 : {
1386 : unsigned int bits = 8;
1387 : do {
1388 1768 : bits++;
1389 1768 : size >>= 1;
1390 1768 : } while (size > 256);
1391 : return bits;
1392 : }
1393 :
1394 : static inline unsigned int block_size(struct block_device *bdev)
1395 : {
1396 : return bdev->bd_block_size;
1397 : }
1398 :
1399 : static inline bool queue_flush_queueable(struct request_queue *q)
1400 : {
1401 : return !q->flush_not_queueable;
1402 : }
1403 :
1404 : typedef struct {struct page *v;} Sector;
1405 :
1406 : unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1407 :
1408 : static inline void put_dev_sector(Sector p)
1409 : {
1410 : page_cache_release(p.v);
1411 : }
1412 :
1413 : struct work_struct;
1414 : int kblockd_schedule_work(struct work_struct *work);
1415 : int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
1416 : int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
1417 :
1418 : #ifdef CONFIG_BLK_CGROUP
1419 : /*
1420 : * This should not be using sched_clock(). A real patch is in progress
1421 : * to fix this up, until that is in place we need to disable preemption
1422 : * around sched_clock() in this function and set_io_start_time_ns().
1423 : */
1424 : static inline void set_start_time_ns(struct request *req)
1425 : {
1426 : preempt_disable();
1427 : req->start_time_ns = sched_clock();
1428 : preempt_enable();
1429 : }
1430 :
1431 : static inline void set_io_start_time_ns(struct request *req)
1432 : {
1433 : preempt_disable();
1434 : req->io_start_time_ns = sched_clock();
1435 : preempt_enable();
1436 : }
1437 :
1438 : static inline uint64_t rq_start_time_ns(struct request *req)
1439 : {
1440 : return req->start_time_ns;
1441 : }
1442 :
1443 : static inline uint64_t rq_io_start_time_ns(struct request *req)
1444 : {
1445 : return req->io_start_time_ns;
1446 : }
1447 : #else
1448 : static inline void set_start_time_ns(struct request *req) {}
1449 : static inline void set_io_start_time_ns(struct request *req) {}
1450 : static inline uint64_t rq_start_time_ns(struct request *req)
1451 : {
1452 : return 0;
1453 : }
1454 : static inline uint64_t rq_io_start_time_ns(struct request *req)
1455 : {
1456 : return 0;
1457 : }
1458 : #endif
1459 :
1460 : #define MODULE_ALIAS_BLOCKDEV(major,minor) \
1461 : MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1462 : #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1463 : MODULE_ALIAS("block-major-" __stringify(major) "-*")
1464 :
1465 : #if defined(CONFIG_BLK_DEV_INTEGRITY)
1466 :
1467 : #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */
1468 : #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */
1469 :
1470 : struct blk_integrity_exchg {
1471 : void *prot_buf;
1472 : void *data_buf;
1473 : sector_t sector;
1474 : unsigned int data_size;
1475 : unsigned short sector_size;
1476 : const char *disk_name;
1477 : };
1478 :
1479 : typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
1480 : typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
1481 : typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
1482 : typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);
1483 :
1484 : struct blk_integrity {
1485 : integrity_gen_fn *generate_fn;
1486 : integrity_vrfy_fn *verify_fn;
1487 : integrity_set_tag_fn *set_tag_fn;
1488 : integrity_get_tag_fn *get_tag_fn;
1489 :
1490 : unsigned short flags;
1491 : unsigned short tuple_size;
1492 : unsigned short sector_size;
1493 : unsigned short tag_size;
1494 :
1495 : const char *name;
1496 :
1497 : struct kobject kobj;
1498 : };
1499 :
1500 : extern bool blk_integrity_is_initialized(struct gendisk *);
1501 : extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1502 : extern void blk_integrity_unregister(struct gendisk *);
1503 : extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1504 : extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1505 : struct scatterlist *);
1506 : extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1507 : extern int blk_integrity_merge_rq(struct request_queue *, struct request *,
1508 : struct request *);
1509 : extern int blk_integrity_merge_bio(struct request_queue *, struct request *,
1510 : struct bio *);
1511 :
1512 : static inline
1513 : struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1514 : {
1515 : return bdev->bd_disk->integrity;
1516 : }
1517 :
1518 : static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1519 : {
1520 : return disk->integrity;
1521 : }
1522 :
1523 : static inline int blk_integrity_rq(struct request *rq)
1524 : {
1525 : if (rq->bio == NULL)
1526 : return 0;
1527 :
1528 : return bio_integrity(rq->bio);
1529 : }
1530 :
1531 : static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1532 : unsigned int segs)
1533 : {
1534 : q->limits.max_integrity_segments = segs;
1535 : }
1536 :
1537 : static inline unsigned short
1538 : queue_max_integrity_segments(struct request_queue *q)
1539 : {
1540 : return q->limits.max_integrity_segments;
1541 : }
1542 :
1543 : #else /* CONFIG_BLK_DEV_INTEGRITY */
1544 :
1545 : struct bio;
1546 : struct block_device;
1547 : struct gendisk;
1548 : struct blk_integrity;
1549 :
1550 : static inline int blk_integrity_rq(struct request *rq)
1551 : {
1552 : return 0;
1553 : }
1554 : static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1555 : struct bio *b)
1556 : {
1557 : return 0;
1558 : }
1559 : static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1560 : struct bio *b,
1561 : struct scatterlist *s)
1562 : {
1563 : return 0;
1564 : }
1565 : static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1566 : {
1567 : return 0;
1568 : }
1569 : static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1570 : {
1571 : return NULL;
1572 : }
1573 : static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1574 : {
1575 : return 0;
1576 : }
1577 : static inline int blk_integrity_register(struct gendisk *d,
1578 : struct blk_integrity *b)
1579 : {
1580 : return 0;
1581 : }
1582 : static inline void blk_integrity_unregister(struct gendisk *d)
1583 : {
1584 : }
1585 : static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1586 : unsigned int segs)
1587 : {
1588 : }
1589 : static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1590 : {
1591 : return 0;
1592 : }
1593 : static inline int blk_integrity_merge_rq(struct request_queue *rq,
1594 : struct request *r1,
1595 : struct request *r2)
1596 : {
1597 : return 0;
1598 : }
1599 : static inline int blk_integrity_merge_bio(struct request_queue *rq,
1600 : struct request *r,
1601 : struct bio *b)
1602 : {
1603 : return 0;
1604 : }
1605 : static inline bool blk_integrity_is_initialized(struct gendisk *g)
1606 : {
1607 : return 0;
1608 : }
1609 :
1610 : #endif /* CONFIG_BLK_DEV_INTEGRITY */
1611 :
1612 : struct block_device_operations {
1613 : int (*open) (struct block_device *, fmode_t);
1614 : void (*release) (struct gendisk *, fmode_t);
1615 : int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
1616 : int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1617 : int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1618 : int (*direct_access) (struct block_device *, sector_t,
1619 : void **, unsigned long *);
1620 : unsigned int (*check_events) (struct gendisk *disk,
1621 : unsigned int clearing);
1622 : /* ->media_changed() is DEPRECATED, use ->check_events() instead */
1623 : int (*media_changed) (struct gendisk *);
1624 : void (*unlock_native_capacity) (struct gendisk *);
1625 : int (*revalidate_disk) (struct gendisk *);
1626 : int (*getgeo)(struct block_device *, struct hd_geometry *);
1627 : /* this callback is with swap_lock and sometimes page table lock held */
1628 : void (*swap_slot_free_notify) (struct block_device *, unsigned long);
1629 : struct module *owner;
1630 : };
1631 :
1632 : extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1633 : unsigned long);
1634 : extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1635 : extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1636 : struct writeback_control *);
1637 : #else /* CONFIG_BLOCK */
1638 :
1639 : struct block_device;
1640 :
1641 : /*
1642 : * stubs for when the block layer is configured out
1643 : */
1644 : #define buffer_heads_over_limit 0
1645 :
1646 : static inline long nr_blockdev_pages(void)
1647 : {
1648 : return 0;
1649 : }
1650 :
1651 : struct blk_plug {
1652 : };
1653 :
1654 : static inline void blk_start_plug(struct blk_plug *plug)
1655 : {
1656 : }
1657 :
1658 : static inline void blk_finish_plug(struct blk_plug *plug)
1659 : {
1660 : }
1661 :
1662 : static inline void blk_flush_plug(struct task_struct *task)
1663 : {
1664 : }
1665 :
1666 : static inline void blk_schedule_flush_plug(struct task_struct *task)
1667 : {
1668 : }
1669 :
1670 :
1671 : static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1672 : {
1673 : return false;
1674 : }
1675 :
1676 : static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1677 : sector_t *error_sector)
1678 : {
1679 : return 0;
1680 : }
1681 :
1682 : #endif /* CONFIG_BLOCK */
1683 :
1684 : #endif
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