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