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