]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | #ifndef _LINUX_BLKDEV_H |
2 | #define _LINUX_BLKDEV_H | |
3 | ||
1da177e4 LT |
4 | #include <linux/major.h> |
5 | #include <linux/genhd.h> | |
6 | #include <linux/list.h> | |
7 | #include <linux/timer.h> | |
8 | #include <linux/workqueue.h> | |
9 | #include <linux/pagemap.h> | |
10 | #include <linux/backing-dev.h> | |
11 | #include <linux/wait.h> | |
12 | #include <linux/mempool.h> | |
13 | #include <linux/bio.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/stringify.h> | |
16 | ||
17 | #include <asm/scatterlist.h> | |
18 | ||
21b2f0c8 CH |
19 | struct scsi_ioctl_command; |
20 | ||
1da177e4 LT |
21 | struct request_queue; |
22 | typedef struct request_queue request_queue_t; | |
23 | struct elevator_queue; | |
24 | typedef struct elevator_queue elevator_t; | |
25 | struct request_pm_state; | |
2056a782 | 26 | struct blk_trace; |
1da177e4 LT |
27 | |
28 | #define BLKDEV_MIN_RQ 4 | |
29 | #define BLKDEV_MAX_RQ 128 /* Default maximum */ | |
30 | ||
31 | /* | |
32 | * This is the per-process anticipatory I/O scheduler state. | |
33 | */ | |
34 | struct as_io_context { | |
35 | spinlock_t lock; | |
36 | ||
37 | void (*dtor)(struct as_io_context *aic); /* destructor */ | |
38 | void (*exit)(struct as_io_context *aic); /* called on task exit */ | |
39 | ||
40 | unsigned long state; | |
41 | atomic_t nr_queued; /* queued reads & sync writes */ | |
42 | atomic_t nr_dispatched; /* number of requests gone to the drivers */ | |
43 | ||
44 | /* IO History tracking */ | |
45 | /* Thinktime */ | |
46 | unsigned long last_end_request; | |
47 | unsigned long ttime_total; | |
48 | unsigned long ttime_samples; | |
49 | unsigned long ttime_mean; | |
50 | /* Layout pattern */ | |
51 | unsigned int seek_samples; | |
52 | sector_t last_request_pos; | |
53 | u64 seek_total; | |
54 | sector_t seek_mean; | |
55 | }; | |
56 | ||
57 | struct cfq_queue; | |
58 | struct cfq_io_context { | |
e2d74ac0 | 59 | struct rb_node rb_node; |
22e2c507 JA |
60 | void *key; |
61 | ||
e2d74ac0 JA |
62 | struct cfq_queue *cfqq[2]; |
63 | ||
22e2c507 JA |
64 | struct io_context *ioc; |
65 | ||
66 | unsigned long last_end_request; | |
206dc69b JA |
67 | sector_t last_request_pos; |
68 | unsigned long last_queue; | |
69 | ||
22e2c507 JA |
70 | unsigned long ttime_total; |
71 | unsigned long ttime_samples; | |
72 | unsigned long ttime_mean; | |
73 | ||
206dc69b JA |
74 | unsigned int seek_samples; |
75 | u64 seek_total; | |
76 | sector_t seek_mean; | |
77 | ||
d9ff4187 AV |
78 | struct list_head queue_list; |
79 | ||
e2d74ac0 JA |
80 | void (*dtor)(struct io_context *); /* destructor */ |
81 | void (*exit)(struct io_context *); /* called on task exit */ | |
1da177e4 LT |
82 | }; |
83 | ||
84 | /* | |
85 | * This is the per-process I/O subsystem state. It is refcounted and | |
86 | * kmalloc'ed. Currently all fields are modified in process io context | |
87 | * (apart from the atomic refcount), so require no locking. | |
88 | */ | |
89 | struct io_context { | |
90 | atomic_t refcount; | |
22e2c507 JA |
91 | struct task_struct *task; |
92 | ||
93 | int (*set_ioprio)(struct io_context *, unsigned int); | |
1da177e4 LT |
94 | |
95 | /* | |
96 | * For request batching | |
97 | */ | |
98 | unsigned long last_waited; /* Time last woken after wait for request */ | |
99 | int nr_batch_requests; /* Number of requests left in the batch */ | |
100 | ||
1da177e4 | 101 | struct as_io_context *aic; |
e2d74ac0 | 102 | struct rb_root cic_root; |
1da177e4 LT |
103 | }; |
104 | ||
105 | void put_io_context(struct io_context *ioc); | |
106 | void exit_io_context(void); | |
8267e268 AV |
107 | struct io_context *current_io_context(gfp_t gfp_flags); |
108 | struct io_context *get_io_context(gfp_t gfp_flags); | |
1da177e4 LT |
109 | void copy_io_context(struct io_context **pdst, struct io_context **psrc); |
110 | void swap_io_context(struct io_context **ioc1, struct io_context **ioc2); | |
111 | ||
112 | struct request; | |
8ffdc655 | 113 | typedef void (rq_end_io_fn)(struct request *, int); |
1da177e4 LT |
114 | |
115 | struct request_list { | |
116 | int count[2]; | |
117 | int starved[2]; | |
cb98fc8b | 118 | int elvpriv; |
1da177e4 LT |
119 | mempool_t *rq_pool; |
120 | wait_queue_head_t wait[2]; | |
1da177e4 LT |
121 | }; |
122 | ||
4aff5e23 JA |
123 | /* |
124 | * request command types | |
125 | */ | |
126 | enum rq_cmd_type_bits { | |
127 | REQ_TYPE_FS = 1, /* fs request */ | |
128 | REQ_TYPE_BLOCK_PC, /* scsi command */ | |
129 | REQ_TYPE_SENSE, /* sense request */ | |
130 | REQ_TYPE_PM_SUSPEND, /* suspend request */ | |
131 | REQ_TYPE_PM_RESUME, /* resume request */ | |
132 | REQ_TYPE_PM_SHUTDOWN, /* shutdown request */ | |
133 | REQ_TYPE_FLUSH, /* flush request */ | |
134 | REQ_TYPE_SPECIAL, /* driver defined type */ | |
135 | REQ_TYPE_LINUX_BLOCK, /* generic block layer message */ | |
136 | /* | |
137 | * for ATA/ATAPI devices. this really doesn't belong here, ide should | |
138 | * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver | |
139 | * private REQ_LB opcodes to differentiate what type of request this is | |
140 | */ | |
141 | REQ_TYPE_ATA_CMD, | |
142 | REQ_TYPE_ATA_TASK, | |
143 | REQ_TYPE_ATA_TASKFILE, | |
144 | }; | |
145 | ||
146 | /* | |
147 | * For request of type REQ_TYPE_LINUX_BLOCK, rq->cmd[0] is the opcode being | |
148 | * sent down (similar to how REQ_TYPE_BLOCK_PC means that ->cmd[] holds a | |
149 | * SCSI cdb. | |
150 | * | |
151 | * 0x00 -> 0x3f are driver private, to be used for whatever purpose they need, | |
152 | * typically to differentiate REQ_TYPE_SPECIAL requests. | |
153 | * | |
154 | */ | |
155 | enum { | |
156 | /* | |
157 | * just examples for now | |
158 | */ | |
159 | REQ_LB_OP_EJECT = 0x40, /* eject request */ | |
160 | REQ_LB_OP_FLUSH = 0x41, /* flush device */ | |
161 | }; | |
162 | ||
163 | /* | |
164 | * request type modified bits. first three bits match BIO_RW* bits, important | |
165 | */ | |
166 | enum rq_flag_bits { | |
167 | __REQ_RW, /* not set, read. set, write */ | |
168 | __REQ_FAILFAST, /* no low level driver retries */ | |
169 | __REQ_SORTED, /* elevator knows about this request */ | |
170 | __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ | |
171 | __REQ_HARDBARRIER, /* may not be passed by drive either */ | |
172 | __REQ_FUA, /* forced unit access */ | |
173 | __REQ_NOMERGE, /* don't touch this for merging */ | |
174 | __REQ_STARTED, /* drive already may have started this one */ | |
175 | __REQ_DONTPREP, /* don't call prep for this one */ | |
176 | __REQ_QUEUED, /* uses queueing */ | |
177 | __REQ_ELVPRIV, /* elevator private data attached */ | |
178 | __REQ_FAILED, /* set if the request failed */ | |
179 | __REQ_QUIET, /* don't worry about errors */ | |
180 | __REQ_PREEMPT, /* set for "ide_preempt" requests */ | |
181 | __REQ_ORDERED_COLOR, /* is before or after barrier */ | |
182 | __REQ_RW_SYNC, /* request is sync (O_DIRECT) */ | |
49171e5c | 183 | __REQ_ALLOCED, /* request came from our alloc pool */ |
4aff5e23 JA |
184 | __REQ_NR_BITS, /* stops here */ |
185 | }; | |
186 | ||
187 | #define REQ_RW (1 << __REQ_RW) | |
188 | #define REQ_FAILFAST (1 << __REQ_FAILFAST) | |
189 | #define REQ_SORTED (1 << __REQ_SORTED) | |
190 | #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) | |
191 | #define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER) | |
192 | #define REQ_FUA (1 << __REQ_FUA) | |
193 | #define REQ_NOMERGE (1 << __REQ_NOMERGE) | |
194 | #define REQ_STARTED (1 << __REQ_STARTED) | |
195 | #define REQ_DONTPREP (1 << __REQ_DONTPREP) | |
196 | #define REQ_QUEUED (1 << __REQ_QUEUED) | |
197 | #define REQ_ELVPRIV (1 << __REQ_ELVPRIV) | |
198 | #define REQ_FAILED (1 << __REQ_FAILED) | |
199 | #define REQ_QUIET (1 << __REQ_QUIET) | |
200 | #define REQ_PREEMPT (1 << __REQ_PREEMPT) | |
201 | #define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR) | |
202 | #define REQ_RW_SYNC (1 << __REQ_RW_SYNC) | |
49171e5c | 203 | #define REQ_ALLOCED (1 << __REQ_ALLOCED) |
4aff5e23 | 204 | |
1da177e4 LT |
205 | #define BLK_MAX_CDB 16 |
206 | ||
207 | /* | |
208 | * try to put the fields that are referenced together in the same cacheline | |
209 | */ | |
210 | struct request { | |
ff856bad JA |
211 | struct list_head queuelist; |
212 | struct list_head donelist; | |
213 | ||
e6a1c874 JA |
214 | request_queue_t *q; |
215 | ||
4aff5e23 JA |
216 | unsigned int cmd_flags; |
217 | enum rq_cmd_type_bits cmd_type; | |
1da177e4 LT |
218 | |
219 | /* Maintain bio traversal state for part by part I/O submission. | |
220 | * hard_* are block layer internals, no driver should touch them! | |
221 | */ | |
222 | ||
223 | sector_t sector; /* next sector to submit */ | |
e6a1c874 | 224 | sector_t hard_sector; /* next sector to complete */ |
1da177e4 | 225 | unsigned long nr_sectors; /* no. of sectors left to submit */ |
e6a1c874 | 226 | unsigned long hard_nr_sectors; /* no. of sectors left to complete */ |
1da177e4 LT |
227 | /* no. of sectors left to submit in the current segment */ |
228 | unsigned int current_nr_sectors; | |
229 | ||
1da177e4 LT |
230 | /* no. of sectors left to complete in the current segment */ |
231 | unsigned int hard_cur_sectors; | |
232 | ||
233 | struct bio *bio; | |
234 | struct bio *biotail; | |
235 | ||
9817064b | 236 | struct hlist_node hash; /* merge hash */ |
e6a1c874 JA |
237 | /* |
238 | * The rb_node is only used inside the io scheduler, requests | |
239 | * are pruned when moved to the dispatch queue. So let the | |
240 | * completion_data share space with the rb_node. | |
241 | */ | |
242 | union { | |
243 | struct rb_node rb_node; /* sort/lookup */ | |
244 | void *completion_data; | |
245 | }; | |
9817064b | 246 | |
ff7d145f JA |
247 | /* |
248 | * two pointers are available for the IO schedulers, if they need | |
249 | * more they have to dynamically allocate it. | |
250 | */ | |
1da177e4 | 251 | void *elevator_private; |
ff7d145f JA |
252 | void *elevator_private2; |
253 | ||
8f34ee75 | 254 | struct gendisk *rq_disk; |
1da177e4 LT |
255 | unsigned long start_time; |
256 | ||
257 | /* Number of scatter-gather DMA addr+len pairs after | |
258 | * physical address coalescing is performed. | |
259 | */ | |
260 | unsigned short nr_phys_segments; | |
261 | ||
262 | /* Number of scatter-gather addr+len pairs after | |
263 | * physical and DMA remapping hardware coalescing is performed. | |
264 | * This is the number of scatter-gather entries the driver | |
265 | * will actually have to deal with after DMA mapping is done. | |
266 | */ | |
267 | unsigned short nr_hw_segments; | |
268 | ||
8f34ee75 JA |
269 | unsigned short ioprio; |
270 | ||
1da177e4 | 271 | void *special; |
8f34ee75 | 272 | char *buffer; |
1da177e4 | 273 | |
cdd60262 JA |
274 | int tag; |
275 | int errors; | |
276 | ||
277 | int ref_count; | |
278 | ||
1da177e4 LT |
279 | /* |
280 | * when request is used as a packet command carrier | |
281 | */ | |
282 | unsigned int cmd_len; | |
283 | unsigned char cmd[BLK_MAX_CDB]; | |
284 | ||
285 | unsigned int data_len; | |
1da177e4 | 286 | unsigned int sense_len; |
8f34ee75 | 287 | void *data; |
1da177e4 LT |
288 | void *sense; |
289 | ||
290 | unsigned int timeout; | |
17e01f21 | 291 | int retries; |
1da177e4 | 292 | |
1da177e4 | 293 | /* |
c00895ab | 294 | * completion callback. |
1da177e4 LT |
295 | */ |
296 | rq_end_io_fn *end_io; | |
297 | void *end_io_data; | |
298 | }; | |
299 | ||
300 | /* | |
4aff5e23 | 301 | * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME |
1da177e4 LT |
302 | * requests. Some step values could eventually be made generic. |
303 | */ | |
304 | struct request_pm_state | |
305 | { | |
306 | /* PM state machine step value, currently driver specific */ | |
307 | int pm_step; | |
308 | /* requested PM state value (S1, S2, S3, S4, ...) */ | |
309 | u32 pm_state; | |
310 | void* data; /* for driver use */ | |
311 | }; | |
312 | ||
313 | #include <linux/elevator.h> | |
314 | ||
315 | typedef int (merge_request_fn) (request_queue_t *, struct request *, | |
316 | struct bio *); | |
317 | typedef int (merge_requests_fn) (request_queue_t *, struct request *, | |
318 | struct request *); | |
319 | typedef void (request_fn_proc) (request_queue_t *q); | |
320 | typedef int (make_request_fn) (request_queue_t *q, struct bio *bio); | |
321 | typedef int (prep_rq_fn) (request_queue_t *, struct request *); | |
322 | typedef void (unplug_fn) (request_queue_t *); | |
323 | ||
324 | struct bio_vec; | |
325 | typedef int (merge_bvec_fn) (request_queue_t *, struct bio *, struct bio_vec *); | |
326 | typedef void (activity_fn) (void *data, int rw); | |
327 | typedef int (issue_flush_fn) (request_queue_t *, struct gendisk *, sector_t *); | |
797e7dbb | 328 | typedef void (prepare_flush_fn) (request_queue_t *, struct request *); |
ff856bad | 329 | typedef void (softirq_done_fn)(struct request *); |
1da177e4 LT |
330 | |
331 | enum blk_queue_state { | |
332 | Queue_down, | |
333 | Queue_up, | |
334 | }; | |
335 | ||
1da177e4 LT |
336 | struct blk_queue_tag { |
337 | struct request **tag_index; /* map of busy tags */ | |
338 | unsigned long *tag_map; /* bit map of free/busy tags */ | |
339 | struct list_head busy_list; /* fifo list of busy tags */ | |
340 | int busy; /* current depth */ | |
341 | int max_depth; /* what we will send to device */ | |
ba025082 | 342 | int real_max_depth; /* what the array can hold */ |
1da177e4 LT |
343 | atomic_t refcnt; /* map can be shared */ |
344 | }; | |
345 | ||
346 | struct request_queue | |
347 | { | |
348 | /* | |
349 | * Together with queue_head for cacheline sharing | |
350 | */ | |
351 | struct list_head queue_head; | |
352 | struct request *last_merge; | |
353 | elevator_t *elevator; | |
354 | ||
355 | /* | |
356 | * the queue request freelist, one for reads and one for writes | |
357 | */ | |
358 | struct request_list rq; | |
359 | ||
360 | request_fn_proc *request_fn; | |
361 | merge_request_fn *back_merge_fn; | |
362 | merge_request_fn *front_merge_fn; | |
363 | merge_requests_fn *merge_requests_fn; | |
364 | make_request_fn *make_request_fn; | |
365 | prep_rq_fn *prep_rq_fn; | |
366 | unplug_fn *unplug_fn; | |
367 | merge_bvec_fn *merge_bvec_fn; | |
368 | activity_fn *activity_fn; | |
369 | issue_flush_fn *issue_flush_fn; | |
370 | prepare_flush_fn *prepare_flush_fn; | |
ff856bad | 371 | softirq_done_fn *softirq_done_fn; |
1da177e4 | 372 | |
8922e16c TH |
373 | /* |
374 | * Dispatch queue sorting | |
375 | */ | |
1b47f531 | 376 | sector_t end_sector; |
8922e16c | 377 | struct request *boundary_rq; |
8922e16c | 378 | |
1da177e4 LT |
379 | /* |
380 | * Auto-unplugging state | |
381 | */ | |
382 | struct timer_list unplug_timer; | |
383 | int unplug_thresh; /* After this many requests */ | |
384 | unsigned long unplug_delay; /* After this many jiffies */ | |
385 | struct work_struct unplug_work; | |
386 | ||
387 | struct backing_dev_info backing_dev_info; | |
388 | ||
389 | /* | |
390 | * The queue owner gets to use this for whatever they like. | |
391 | * ll_rw_blk doesn't touch it. | |
392 | */ | |
393 | void *queuedata; | |
394 | ||
395 | void *activity_data; | |
396 | ||
397 | /* | |
398 | * queue needs bounce pages for pages above this limit | |
399 | */ | |
400 | unsigned long bounce_pfn; | |
8267e268 | 401 | gfp_t bounce_gfp; |
1da177e4 LT |
402 | |
403 | /* | |
404 | * various queue flags, see QUEUE_* below | |
405 | */ | |
406 | unsigned long queue_flags; | |
407 | ||
408 | /* | |
152587de JA |
409 | * protects queue structures from reentrancy. ->__queue_lock should |
410 | * _never_ be used directly, it is queue private. always use | |
411 | * ->queue_lock. | |
1da177e4 | 412 | */ |
152587de | 413 | spinlock_t __queue_lock; |
1da177e4 LT |
414 | spinlock_t *queue_lock; |
415 | ||
416 | /* | |
417 | * queue kobject | |
418 | */ | |
419 | struct kobject kobj; | |
420 | ||
421 | /* | |
422 | * queue settings | |
423 | */ | |
424 | unsigned long nr_requests; /* Max # of requests */ | |
425 | unsigned int nr_congestion_on; | |
426 | unsigned int nr_congestion_off; | |
427 | unsigned int nr_batching; | |
428 | ||
2cb2e147 JA |
429 | unsigned int max_sectors; |
430 | unsigned int max_hw_sectors; | |
1da177e4 LT |
431 | unsigned short max_phys_segments; |
432 | unsigned short max_hw_segments; | |
433 | unsigned short hardsect_size; | |
434 | unsigned int max_segment_size; | |
435 | ||
436 | unsigned long seg_boundary_mask; | |
437 | unsigned int dma_alignment; | |
438 | ||
439 | struct blk_queue_tag *queue_tags; | |
440 | ||
15853af9 | 441 | unsigned int nr_sorted; |
1da177e4 LT |
442 | unsigned int in_flight; |
443 | ||
444 | /* | |
445 | * sg stuff | |
446 | */ | |
447 | unsigned int sg_timeout; | |
448 | unsigned int sg_reserved_size; | |
1946089a | 449 | int node; |
6c5c9341 | 450 | #ifdef CONFIG_BLK_DEV_IO_TRACE |
2056a782 | 451 | struct blk_trace *blk_trace; |
6c5c9341 | 452 | #endif |
1da177e4 LT |
453 | /* |
454 | * reserved for flush operations | |
455 | */ | |
797e7dbb TH |
456 | unsigned int ordered, next_ordered, ordseq; |
457 | int orderr, ordcolor; | |
458 | struct request pre_flush_rq, bar_rq, post_flush_rq; | |
459 | struct request *orig_bar_rq; | |
460 | unsigned int bi_size; | |
483f4afc AV |
461 | |
462 | struct mutex sysfs_lock; | |
1da177e4 LT |
463 | }; |
464 | ||
1da177e4 LT |
465 | #define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */ |
466 | #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ | |
467 | #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ | |
468 | #define QUEUE_FLAG_READFULL 3 /* write queue has been filled */ | |
469 | #define QUEUE_FLAG_WRITEFULL 4 /* read queue has been filled */ | |
470 | #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ | |
471 | #define QUEUE_FLAG_REENTER 6 /* Re-entrancy avoidance */ | |
472 | #define QUEUE_FLAG_PLUGGED 7 /* queue is plugged */ | |
64521d1a | 473 | #define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */ |
797e7dbb TH |
474 | |
475 | enum { | |
476 | /* | |
477 | * Hardbarrier is supported with one of the following methods. | |
478 | * | |
479 | * NONE : hardbarrier unsupported | |
480 | * DRAIN : ordering by draining is enough | |
481 | * DRAIN_FLUSH : ordering by draining w/ pre and post flushes | |
482 | * DRAIN_FUA : ordering by draining w/ pre flush and FUA write | |
483 | * TAG : ordering by tag is enough | |
484 | * TAG_FLUSH : ordering by tag w/ pre and post flushes | |
485 | * TAG_FUA : ordering by tag w/ pre flush and FUA write | |
486 | */ | |
487 | QUEUE_ORDERED_NONE = 0x00, | |
488 | QUEUE_ORDERED_DRAIN = 0x01, | |
489 | QUEUE_ORDERED_TAG = 0x02, | |
490 | ||
491 | QUEUE_ORDERED_PREFLUSH = 0x10, | |
492 | QUEUE_ORDERED_POSTFLUSH = 0x20, | |
493 | QUEUE_ORDERED_FUA = 0x40, | |
494 | ||
495 | QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN | | |
496 | QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH, | |
497 | QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN | | |
498 | QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_FUA, | |
499 | QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG | | |
500 | QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH, | |
501 | QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG | | |
502 | QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_FUA, | |
503 | ||
504 | /* | |
505 | * Ordered operation sequence | |
506 | */ | |
507 | QUEUE_ORDSEQ_STARTED = 0x01, /* flushing in progress */ | |
508 | QUEUE_ORDSEQ_DRAIN = 0x02, /* waiting for the queue to be drained */ | |
509 | QUEUE_ORDSEQ_PREFLUSH = 0x04, /* pre-flushing in progress */ | |
510 | QUEUE_ORDSEQ_BAR = 0x08, /* original barrier req in progress */ | |
511 | QUEUE_ORDSEQ_POSTFLUSH = 0x10, /* post-flushing in progress */ | |
512 | QUEUE_ORDSEQ_DONE = 0x20, | |
513 | }; | |
1da177e4 LT |
514 | |
515 | #define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags) | |
516 | #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) | |
517 | #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) | |
797e7dbb | 518 | #define blk_queue_flushing(q) ((q)->ordseq) |
1da177e4 | 519 | |
4aff5e23 JA |
520 | #define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS) |
521 | #define blk_pc_request(rq) ((rq)->cmd_type == REQ_TYPE_BLOCK_PC) | |
522 | #define blk_special_request(rq) ((rq)->cmd_type == REQ_TYPE_SPECIAL) | |
523 | #define blk_sense_request(rq) ((rq)->cmd_type == REQ_TYPE_SENSE) | |
524 | ||
525 | #define blk_noretry_request(rq) ((rq)->cmd_flags & REQ_FAILFAST) | |
526 | #define blk_rq_started(rq) ((rq)->cmd_flags & REQ_STARTED) | |
1da177e4 LT |
527 | |
528 | #define blk_account_rq(rq) (blk_rq_started(rq) && blk_fs_request(rq)) | |
529 | ||
4aff5e23 JA |
530 | #define blk_pm_suspend_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND) |
531 | #define blk_pm_resume_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_RESUME) | |
1da177e4 | 532 | #define blk_pm_request(rq) \ |
4aff5e23 | 533 | (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq)) |
1da177e4 | 534 | |
4aff5e23 JA |
535 | #define blk_sorted_rq(rq) ((rq)->cmd_flags & REQ_SORTED) |
536 | #define blk_barrier_rq(rq) ((rq)->cmd_flags & REQ_HARDBARRIER) | |
537 | #define blk_fua_rq(rq) ((rq)->cmd_flags & REQ_FUA) | |
1da177e4 LT |
538 | |
539 | #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) | |
540 | ||
4aff5e23 | 541 | #define rq_data_dir(rq) ((rq)->cmd_flags & 1) |
1da177e4 | 542 | |
9e2585a8 JA |
543 | /* |
544 | * We regard a request as sync, if it's a READ or a SYNC write. | |
545 | */ | |
546 | #define rq_is_sync(rq) (rq_data_dir((rq)) == READ || (rq)->cmd_flags & REQ_RW_SYNC) | |
547 | ||
1da177e4 LT |
548 | static inline int blk_queue_full(struct request_queue *q, int rw) |
549 | { | |
550 | if (rw == READ) | |
551 | return test_bit(QUEUE_FLAG_READFULL, &q->queue_flags); | |
552 | return test_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags); | |
553 | } | |
554 | ||
555 | static inline void blk_set_queue_full(struct request_queue *q, int rw) | |
556 | { | |
557 | if (rw == READ) | |
558 | set_bit(QUEUE_FLAG_READFULL, &q->queue_flags); | |
559 | else | |
560 | set_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags); | |
561 | } | |
562 | ||
563 | static inline void blk_clear_queue_full(struct request_queue *q, int rw) | |
564 | { | |
565 | if (rw == READ) | |
566 | clear_bit(QUEUE_FLAG_READFULL, &q->queue_flags); | |
567 | else | |
568 | clear_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags); | |
569 | } | |
570 | ||
571 | ||
572 | /* | |
573 | * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may | |
574 | * it already be started by driver. | |
575 | */ | |
576 | #define RQ_NOMERGE_FLAGS \ | |
577 | (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER) | |
578 | #define rq_mergeable(rq) \ | |
4aff5e23 | 579 | (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq))) |
1da177e4 LT |
580 | |
581 | /* | |
582 | * noop, requests are automagically marked as active/inactive by I/O | |
583 | * scheduler -- see elv_next_request | |
584 | */ | |
585 | #define blk_queue_headactive(q, head_active) | |
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 | #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) | |
604 | #define BLK_BOUNCE_ANY ((u64)blk_max_pfn << PAGE_SHIFT) | |
605 | #define BLK_BOUNCE_ISA (ISA_DMA_THRESHOLD) | |
606 | ||
607 | #ifdef CONFIG_MMU | |
608 | extern int init_emergency_isa_pool(void); | |
609 | extern void blk_queue_bounce(request_queue_t *q, struct bio **bio); | |
610 | #else | |
611 | static inline int init_emergency_isa_pool(void) | |
612 | { | |
613 | return 0; | |
614 | } | |
615 | static inline void blk_queue_bounce(request_queue_t *q, struct bio **bio) | |
616 | { | |
617 | } | |
618 | #endif /* CONFIG_MMU */ | |
619 | ||
620 | #define rq_for_each_bio(_bio, rq) \ | |
621 | if ((rq->bio)) \ | |
622 | for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) | |
623 | ||
624 | struct sec_size { | |
625 | unsigned block_size; | |
626 | unsigned block_size_bits; | |
627 | }; | |
628 | ||
629 | extern int blk_register_queue(struct gendisk *disk); | |
630 | extern void blk_unregister_queue(struct gendisk *disk); | |
631 | extern void register_disk(struct gendisk *dev); | |
632 | extern void generic_make_request(struct bio *bio); | |
633 | extern void blk_put_request(struct request *); | |
6e39b69e | 634 | extern void __blk_put_request(request_queue_t *, struct request *); |
8ffdc655 | 635 | extern void blk_end_sync_rq(struct request *rq, int error); |
8267e268 | 636 | extern struct request *blk_get_request(request_queue_t *, int, gfp_t); |
867d1191 | 637 | extern void blk_insert_request(request_queue_t *, struct request *, int, void *); |
1da177e4 LT |
638 | extern void blk_requeue_request(request_queue_t *, struct request *); |
639 | extern void blk_plug_device(request_queue_t *); | |
640 | extern int blk_remove_plug(request_queue_t *); | |
641 | extern void blk_recount_segments(request_queue_t *, struct bio *); | |
1da177e4 | 642 | extern int scsi_cmd_ioctl(struct file *, struct gendisk *, unsigned int, void __user *); |
21b2f0c8 CH |
643 | extern int sg_scsi_ioctl(struct file *, struct request_queue *, |
644 | struct gendisk *, struct scsi_ioctl_command __user *); | |
1da177e4 LT |
645 | extern void blk_start_queue(request_queue_t *q); |
646 | extern void blk_stop_queue(request_queue_t *q); | |
647 | extern void blk_sync_queue(struct request_queue *q); | |
648 | extern void __blk_stop_queue(request_queue_t *q); | |
649 | extern void blk_run_queue(request_queue_t *); | |
650 | extern void blk_queue_activity_fn(request_queue_t *, activity_fn *, void *); | |
dd1cab95 JA |
651 | extern int blk_rq_map_user(request_queue_t *, struct request *, void __user *, unsigned int); |
652 | extern int blk_rq_unmap_user(struct bio *, unsigned int); | |
8267e268 | 653 | extern int blk_rq_map_kern(request_queue_t *, struct request *, void *, unsigned int, gfp_t); |
f1970baf | 654 | extern int blk_rq_map_user_iov(request_queue_t *, struct request *, struct sg_iovec *, int); |
994ca9a1 JB |
655 | extern int blk_execute_rq(request_queue_t *, struct gendisk *, |
656 | struct request *, int); | |
6e39b69e | 657 | extern void blk_execute_rq_nowait(request_queue_t *, struct gendisk *, |
15fc858a | 658 | struct request *, int, rq_end_io_fn *); |
6e39b69e | 659 | |
1da177e4 LT |
660 | static inline request_queue_t *bdev_get_queue(struct block_device *bdev) |
661 | { | |
662 | return bdev->bd_disk->queue; | |
663 | } | |
664 | ||
665 | static inline void blk_run_backing_dev(struct backing_dev_info *bdi, | |
666 | struct page *page) | |
667 | { | |
668 | if (bdi && bdi->unplug_io_fn) | |
669 | bdi->unplug_io_fn(bdi, page); | |
670 | } | |
671 | ||
672 | static inline void blk_run_address_space(struct address_space *mapping) | |
673 | { | |
674 | if (mapping) | |
675 | blk_run_backing_dev(mapping->backing_dev_info, NULL); | |
676 | } | |
677 | ||
678 | /* | |
679 | * end_request() and friends. Must be called with the request queue spinlock | |
680 | * acquired. All functions called within end_request() _must_be_ atomic. | |
681 | * | |
682 | * Several drivers define their own end_request and call | |
683 | * end_that_request_first() and end_that_request_last() | |
684 | * for parts of the original function. This prevents | |
685 | * code duplication in drivers. | |
686 | */ | |
687 | extern int end_that_request_first(struct request *, int, int); | |
688 | extern int end_that_request_chunk(struct request *, int, int); | |
8ffdc655 | 689 | extern void end_that_request_last(struct request *, int); |
1da177e4 | 690 | extern void end_request(struct request *req, int uptodate); |
ff856bad JA |
691 | extern void blk_complete_request(struct request *); |
692 | ||
693 | static inline int rq_all_done(struct request *rq, unsigned int nr_bytes) | |
694 | { | |
695 | if (blk_fs_request(rq)) | |
696 | return (nr_bytes >= (rq->hard_nr_sectors << 9)); | |
697 | else if (blk_pc_request(rq)) | |
698 | return nr_bytes >= rq->data_len; | |
699 | ||
700 | return 0; | |
701 | } | |
1da177e4 LT |
702 | |
703 | /* | |
704 | * end_that_request_first/chunk() takes an uptodate argument. we account | |
705 | * any value <= as an io error. 0 means -EIO for compatability reasons, | |
706 | * any other < 0 value is the direct error type. An uptodate value of | |
707 | * 1 indicates successful io completion | |
708 | */ | |
709 | #define end_io_error(uptodate) (unlikely((uptodate) <= 0)) | |
710 | ||
711 | static inline void blkdev_dequeue_request(struct request *req) | |
712 | { | |
8922e16c | 713 | elv_dequeue_request(req->q, req); |
1da177e4 | 714 | } |
1da177e4 | 715 | |
1da177e4 LT |
716 | /* |
717 | * Access functions for manipulating queue properties | |
718 | */ | |
1946089a CL |
719 | extern request_queue_t *blk_init_queue_node(request_fn_proc *rfn, |
720 | spinlock_t *lock, int node_id); | |
1da177e4 LT |
721 | extern request_queue_t *blk_init_queue(request_fn_proc *, spinlock_t *); |
722 | extern void blk_cleanup_queue(request_queue_t *); | |
723 | extern void blk_queue_make_request(request_queue_t *, make_request_fn *); | |
724 | extern void blk_queue_bounce_limit(request_queue_t *, u64); | |
2cb2e147 | 725 | extern void blk_queue_max_sectors(request_queue_t *, unsigned int); |
1da177e4 LT |
726 | extern void blk_queue_max_phys_segments(request_queue_t *, unsigned short); |
727 | extern void blk_queue_max_hw_segments(request_queue_t *, unsigned short); | |
728 | extern void blk_queue_max_segment_size(request_queue_t *, unsigned int); | |
729 | extern void blk_queue_hardsect_size(request_queue_t *, unsigned short); | |
730 | extern void blk_queue_stack_limits(request_queue_t *t, request_queue_t *b); | |
731 | extern void blk_queue_segment_boundary(request_queue_t *, unsigned long); | |
732 | extern void blk_queue_prep_rq(request_queue_t *, prep_rq_fn *pfn); | |
733 | extern void blk_queue_merge_bvec(request_queue_t *, merge_bvec_fn *); | |
734 | extern void blk_queue_dma_alignment(request_queue_t *, int); | |
ff856bad | 735 | extern void blk_queue_softirq_done(request_queue_t *, softirq_done_fn *); |
1da177e4 | 736 | extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); |
797e7dbb | 737 | extern int blk_queue_ordered(request_queue_t *, unsigned, prepare_flush_fn *); |
1da177e4 | 738 | extern void blk_queue_issue_flush_fn(request_queue_t *, issue_flush_fn *); |
797e7dbb TH |
739 | extern int blk_do_ordered(request_queue_t *, struct request **); |
740 | extern unsigned blk_ordered_cur_seq(request_queue_t *); | |
741 | extern unsigned blk_ordered_req_seq(struct request *); | |
742 | extern void blk_ordered_complete_seq(request_queue_t *, unsigned, int); | |
1da177e4 LT |
743 | |
744 | extern int blk_rq_map_sg(request_queue_t *, struct request *, struct scatterlist *); | |
745 | extern void blk_dump_rq_flags(struct request *, char *); | |
746 | extern void generic_unplug_device(request_queue_t *); | |
747 | extern void __generic_unplug_device(request_queue_t *); | |
748 | extern long nr_blockdev_pages(void); | |
1da177e4 LT |
749 | |
750 | int blk_get_queue(request_queue_t *); | |
8267e268 AV |
751 | request_queue_t *blk_alloc_queue(gfp_t); |
752 | request_queue_t *blk_alloc_queue_node(gfp_t, int); | |
483f4afc | 753 | extern void blk_put_queue(request_queue_t *); |
1da177e4 LT |
754 | |
755 | /* | |
756 | * tag stuff | |
757 | */ | |
758 | #define blk_queue_tag_depth(q) ((q)->queue_tags->busy) | |
759 | #define blk_queue_tag_queue(q) ((q)->queue_tags->busy < (q)->queue_tags->max_depth) | |
4aff5e23 | 760 | #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED) |
1da177e4 LT |
761 | extern int blk_queue_start_tag(request_queue_t *, struct request *); |
762 | extern struct request *blk_queue_find_tag(request_queue_t *, int); | |
763 | extern void blk_queue_end_tag(request_queue_t *, struct request *); | |
764 | extern int blk_queue_init_tags(request_queue_t *, int, struct blk_queue_tag *); | |
765 | extern void blk_queue_free_tags(request_queue_t *); | |
766 | extern int blk_queue_resize_tags(request_queue_t *, int); | |
767 | extern void blk_queue_invalidate_tags(request_queue_t *); | |
768 | extern long blk_congestion_wait(int rw, long timeout); | |
492dfb48 JB |
769 | extern struct blk_queue_tag *blk_init_tags(int); |
770 | extern void blk_free_tags(struct blk_queue_tag *); | |
275a082f | 771 | extern void blk_congestion_end(int rw); |
1da177e4 LT |
772 | |
773 | extern void blk_rq_bio_prep(request_queue_t *, struct request *, struct bio *); | |
774 | extern int blkdev_issue_flush(struct block_device *, sector_t *); | |
775 | ||
776 | #define MAX_PHYS_SEGMENTS 128 | |
777 | #define MAX_HW_SEGMENTS 128 | |
defd94b7 MC |
778 | #define SAFE_MAX_SECTORS 255 |
779 | #define BLK_DEF_MAX_SECTORS 1024 | |
1da177e4 LT |
780 | |
781 | #define MAX_SEGMENT_SIZE 65536 | |
782 | ||
783 | #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) | |
784 | ||
1da177e4 LT |
785 | static inline int queue_hardsect_size(request_queue_t *q) |
786 | { | |
787 | int retval = 512; | |
788 | ||
789 | if (q && q->hardsect_size) | |
790 | retval = q->hardsect_size; | |
791 | ||
792 | return retval; | |
793 | } | |
794 | ||
795 | static inline int bdev_hardsect_size(struct block_device *bdev) | |
796 | { | |
797 | return queue_hardsect_size(bdev_get_queue(bdev)); | |
798 | } | |
799 | ||
800 | static inline int queue_dma_alignment(request_queue_t *q) | |
801 | { | |
802 | int retval = 511; | |
803 | ||
804 | if (q && q->dma_alignment) | |
805 | retval = q->dma_alignment; | |
806 | ||
807 | return retval; | |
808 | } | |
809 | ||
810 | static inline int bdev_dma_aligment(struct block_device *bdev) | |
811 | { | |
812 | return queue_dma_alignment(bdev_get_queue(bdev)); | |
813 | } | |
814 | ||
815 | #define blk_finished_io(nsects) do { } while (0) | |
816 | #define blk_started_io(nsects) do { } while (0) | |
817 | ||
818 | /* assumes size > 256 */ | |
819 | static inline unsigned int blksize_bits(unsigned int size) | |
820 | { | |
821 | unsigned int bits = 8; | |
822 | do { | |
823 | bits++; | |
824 | size >>= 1; | |
825 | } while (size > 256); | |
826 | return bits; | |
827 | } | |
828 | ||
2befb9e3 | 829 | static inline unsigned int block_size(struct block_device *bdev) |
1da177e4 LT |
830 | { |
831 | return bdev->bd_block_size; | |
832 | } | |
833 | ||
834 | typedef struct {struct page *v;} Sector; | |
835 | ||
836 | unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); | |
837 | ||
838 | static inline void put_dev_sector(Sector p) | |
839 | { | |
840 | page_cache_release(p.v); | |
841 | } | |
842 | ||
843 | struct work_struct; | |
844 | int kblockd_schedule_work(struct work_struct *work); | |
845 | void kblockd_flush(void); | |
846 | ||
847 | #ifdef CONFIG_LBD | |
848 | # include <asm/div64.h> | |
849 | # define sector_div(a, b) do_div(a, b) | |
850 | #else | |
851 | # define sector_div(n, b)( \ | |
852 | { \ | |
853 | int _res; \ | |
854 | _res = (n) % (b); \ | |
855 | (n) /= (b); \ | |
856 | _res; \ | |
857 | } \ | |
858 | ) | |
859 | #endif | |
860 | ||
861 | #define MODULE_ALIAS_BLOCKDEV(major,minor) \ | |
862 | MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) | |
863 | #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ | |
864 | MODULE_ALIAS("block-major-" __stringify(major) "-*") | |
865 | ||
866 | ||
867 | #endif |