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1da177e4 LT |
1 | #ifndef _LINUX_BLKDEV_H |
2 | #define _LINUX_BLKDEV_H | |
3 | ||
f5ff8422 JA |
4 | #ifdef CONFIG_BLOCK |
5 | ||
bcfd8d36 | 6 | #include <linux/sched.h> |
1da177e4 LT |
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/module.h> | |
18 | #include <linux/stringify.h> | |
3e6053d7 | 19 | #include <linux/gfp.h> |
d351af01 | 20 | #include <linux/bsg.h> |
c7c22e4d | 21 | #include <linux/smp.h> |
1da177e4 LT |
22 | |
23 | #include <asm/scatterlist.h> | |
24 | ||
21b2f0c8 CH |
25 | struct scsi_ioctl_command; |
26 | ||
1da177e4 | 27 | struct request_queue; |
1da177e4 | 28 | struct elevator_queue; |
1da177e4 | 29 | struct request_pm_state; |
2056a782 | 30 | struct blk_trace; |
3d6392cf JA |
31 | struct request; |
32 | struct sg_io_hdr; | |
1da177e4 LT |
33 | |
34 | #define BLKDEV_MIN_RQ 4 | |
35 | #define BLKDEV_MAX_RQ 128 /* Default maximum */ | |
36 | ||
1da177e4 | 37 | struct request; |
8ffdc655 | 38 | typedef void (rq_end_io_fn)(struct request *, int); |
1da177e4 LT |
39 | |
40 | struct request_list { | |
1faa16d2 JA |
41 | /* |
42 | * count[], starved[], and wait[] are indexed by | |
43 | * BLK_RW_SYNC/BLK_RW_ASYNC | |
44 | */ | |
1da177e4 LT |
45 | int count[2]; |
46 | int starved[2]; | |
cb98fc8b | 47 | int elvpriv; |
1da177e4 LT |
48 | mempool_t *rq_pool; |
49 | wait_queue_head_t wait[2]; | |
1da177e4 LT |
50 | }; |
51 | ||
4aff5e23 JA |
52 | /* |
53 | * request command types | |
54 | */ | |
55 | enum rq_cmd_type_bits { | |
56 | REQ_TYPE_FS = 1, /* fs request */ | |
57 | REQ_TYPE_BLOCK_PC, /* scsi command */ | |
58 | REQ_TYPE_SENSE, /* sense request */ | |
59 | REQ_TYPE_PM_SUSPEND, /* suspend request */ | |
60 | REQ_TYPE_PM_RESUME, /* resume request */ | |
61 | REQ_TYPE_PM_SHUTDOWN, /* shutdown request */ | |
4aff5e23 JA |
62 | REQ_TYPE_SPECIAL, /* driver defined type */ |
63 | REQ_TYPE_LINUX_BLOCK, /* generic block layer message */ | |
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 | */ | |
4aff5e23 | 69 | REQ_TYPE_ATA_TASKFILE, |
cea2885a | 70 | REQ_TYPE_ATA_PC, |
4aff5e23 JA |
71 | }; |
72 | ||
73 | /* | |
74 | * For request of type REQ_TYPE_LINUX_BLOCK, rq->cmd[0] is the opcode being | |
75 | * sent down (similar to how REQ_TYPE_BLOCK_PC means that ->cmd[] holds a | |
76 | * SCSI cdb. | |
77 | * | |
78 | * 0x00 -> 0x3f are driver private, to be used for whatever purpose they need, | |
79 | * typically to differentiate REQ_TYPE_SPECIAL requests. | |
80 | * | |
81 | */ | |
82 | enum { | |
4aff5e23 | 83 | REQ_LB_OP_EJECT = 0x40, /* eject request */ |
1a8e2bdd | 84 | REQ_LB_OP_FLUSH = 0x41, /* flush request */ |
4aff5e23 JA |
85 | }; |
86 | ||
87 | /* | |
1f98a13f | 88 | * request type modified bits. first four bits match BIO_RW* bits, important |
4aff5e23 JA |
89 | */ |
90 | enum rq_flag_bits { | |
91 | __REQ_RW, /* not set, read. set, write */ | |
6000a368 MC |
92 | __REQ_FAILFAST_DEV, /* no driver retries of device errors */ |
93 | __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */ | |
94 | __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */ | |
a82afdfc | 95 | /* above flags must match BIO_RW_* */ |
fb2dce86 | 96 | __REQ_DISCARD, /* request to discard sectors */ |
4aff5e23 JA |
97 | __REQ_SORTED, /* elevator knows about this request */ |
98 | __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ | |
99 | __REQ_HARDBARRIER, /* may not be passed by drive either */ | |
100 | __REQ_FUA, /* forced unit access */ | |
101 | __REQ_NOMERGE, /* don't touch this for merging */ | |
102 | __REQ_STARTED, /* drive already may have started this one */ | |
103 | __REQ_DONTPREP, /* don't call prep for this one */ | |
104 | __REQ_QUEUED, /* uses queueing */ | |
105 | __REQ_ELVPRIV, /* elevator private data attached */ | |
106 | __REQ_FAILED, /* set if the request failed */ | |
107 | __REQ_QUIET, /* don't worry about errors */ | |
108 | __REQ_PREEMPT, /* set for "ide_preempt" requests */ | |
109 | __REQ_ORDERED_COLOR, /* is before or after barrier */ | |
1faa16d2 | 110 | __REQ_RW_SYNC, /* request is sync (sync write or read) */ |
49171e5c | 111 | __REQ_ALLOCED, /* request came from our alloc pool */ |
5404bc7a | 112 | __REQ_RW_META, /* metadata io request */ |
f18573ab | 113 | __REQ_COPY_USER, /* contains copies of user pages */ |
7ba1ba12 | 114 | __REQ_INTEGRITY, /* integrity metadata has been remapped */ |
aeb6fafb | 115 | __REQ_NOIDLE, /* Don't anticipate more IO after this one */ |
42dad764 | 116 | __REQ_IO_STAT, /* account I/O stat */ |
80a761fd | 117 | __REQ_MIXED_MERGE, /* merge of different types, fail separately */ |
4aff5e23 JA |
118 | __REQ_NR_BITS, /* stops here */ |
119 | }; | |
120 | ||
121 | #define REQ_RW (1 << __REQ_RW) | |
6000a368 MC |
122 | #define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV) |
123 | #define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT) | |
124 | #define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER) | |
fb2dce86 | 125 | #define REQ_DISCARD (1 << __REQ_DISCARD) |
4aff5e23 JA |
126 | #define REQ_SORTED (1 << __REQ_SORTED) |
127 | #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) | |
128 | #define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER) | |
129 | #define REQ_FUA (1 << __REQ_FUA) | |
130 | #define REQ_NOMERGE (1 << __REQ_NOMERGE) | |
131 | #define REQ_STARTED (1 << __REQ_STARTED) | |
132 | #define REQ_DONTPREP (1 << __REQ_DONTPREP) | |
133 | #define REQ_QUEUED (1 << __REQ_QUEUED) | |
134 | #define REQ_ELVPRIV (1 << __REQ_ELVPRIV) | |
135 | #define REQ_FAILED (1 << __REQ_FAILED) | |
136 | #define REQ_QUIET (1 << __REQ_QUIET) | |
137 | #define REQ_PREEMPT (1 << __REQ_PREEMPT) | |
138 | #define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR) | |
139 | #define REQ_RW_SYNC (1 << __REQ_RW_SYNC) | |
49171e5c | 140 | #define REQ_ALLOCED (1 << __REQ_ALLOCED) |
5404bc7a | 141 | #define REQ_RW_META (1 << __REQ_RW_META) |
f18573ab | 142 | #define REQ_COPY_USER (1 << __REQ_COPY_USER) |
7ba1ba12 | 143 | #define REQ_INTEGRITY (1 << __REQ_INTEGRITY) |
aeb6fafb | 144 | #define REQ_NOIDLE (1 << __REQ_NOIDLE) |
42dad764 | 145 | #define REQ_IO_STAT (1 << __REQ_IO_STAT) |
80a761fd | 146 | #define REQ_MIXED_MERGE (1 << __REQ_MIXED_MERGE) |
4aff5e23 | 147 | |
a82afdfc TH |
148 | #define REQ_FAILFAST_MASK (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | \ |
149 | REQ_FAILFAST_DRIVER) | |
150 | ||
1da177e4 LT |
151 | #define BLK_MAX_CDB 16 |
152 | ||
153 | /* | |
63a71386 JA |
154 | * try to put the fields that are referenced together in the same cacheline. |
155 | * if you modify this structure, be sure to check block/blk-core.c:rq_init() | |
156 | * as well! | |
1da177e4 LT |
157 | */ |
158 | struct request { | |
ff856bad | 159 | struct list_head queuelist; |
c7c22e4d JA |
160 | struct call_single_data csd; |
161 | int cpu; | |
ff856bad | 162 | |
165125e1 | 163 | struct request_queue *q; |
e6a1c874 | 164 | |
4aff5e23 JA |
165 | unsigned int cmd_flags; |
166 | enum rq_cmd_type_bits cmd_type; | |
242f9dcb | 167 | unsigned long atomic_flags; |
1da177e4 | 168 | |
a2dec7b3 TH |
169 | /* the following two fields are internal, NEVER access directly */ |
170 | sector_t __sector; /* sector cursor */ | |
171 | unsigned int __data_len; /* total data len */ | |
1da177e4 LT |
172 | |
173 | struct bio *bio; | |
174 | struct bio *biotail; | |
175 | ||
9817064b | 176 | struct hlist_node hash; /* merge hash */ |
e6a1c874 JA |
177 | /* |
178 | * The rb_node is only used inside the io scheduler, requests | |
179 | * are pruned when moved to the dispatch queue. So let the | |
180 | * completion_data share space with the rb_node. | |
181 | */ | |
182 | union { | |
183 | struct rb_node rb_node; /* sort/lookup */ | |
184 | void *completion_data; | |
185 | }; | |
9817064b | 186 | |
ff7d145f JA |
187 | /* |
188 | * two pointers are available for the IO schedulers, if they need | |
189 | * more they have to dynamically allocate it. | |
190 | */ | |
1da177e4 | 191 | void *elevator_private; |
ff7d145f JA |
192 | void *elevator_private2; |
193 | ||
8f34ee75 | 194 | struct gendisk *rq_disk; |
1da177e4 LT |
195 | unsigned long start_time; |
196 | ||
197 | /* Number of scatter-gather DMA addr+len pairs after | |
198 | * physical address coalescing is performed. | |
199 | */ | |
200 | unsigned short nr_phys_segments; | |
201 | ||
8f34ee75 JA |
202 | unsigned short ioprio; |
203 | ||
731ec497 TH |
204 | void *special; /* opaque pointer available for LLD use */ |
205 | char *buffer; /* kaddr of the current segment if available */ | |
1da177e4 | 206 | |
cdd60262 JA |
207 | int tag; |
208 | int errors; | |
209 | ||
210 | int ref_count; | |
211 | ||
1da177e4 LT |
212 | /* |
213 | * when request is used as a packet command carrier | |
214 | */ | |
d7e3c324 FT |
215 | unsigned short cmd_len; |
216 | unsigned char __cmd[BLK_MAX_CDB]; | |
217 | unsigned char *cmd; | |
1da177e4 | 218 | |
7a85f889 | 219 | unsigned int extra_len; /* length of alignment and padding */ |
1da177e4 | 220 | unsigned int sense_len; |
c3a4d78c | 221 | unsigned int resid_len; /* residual count */ |
1da177e4 LT |
222 | void *sense; |
223 | ||
242f9dcb JA |
224 | unsigned long deadline; |
225 | struct list_head timeout_list; | |
1da177e4 | 226 | unsigned int timeout; |
17e01f21 | 227 | int retries; |
1da177e4 | 228 | |
1da177e4 | 229 | /* |
c00895ab | 230 | * completion callback. |
1da177e4 LT |
231 | */ |
232 | rq_end_io_fn *end_io; | |
233 | void *end_io_data; | |
abae1fde FT |
234 | |
235 | /* for bidi */ | |
236 | struct request *next_rq; | |
1da177e4 LT |
237 | }; |
238 | ||
766ca442 FLVC |
239 | static inline unsigned short req_get_ioprio(struct request *req) |
240 | { | |
241 | return req->ioprio; | |
242 | } | |
243 | ||
1da177e4 | 244 | /* |
4aff5e23 | 245 | * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME |
1da177e4 LT |
246 | * requests. Some step values could eventually be made generic. |
247 | */ | |
248 | struct request_pm_state | |
249 | { | |
250 | /* PM state machine step value, currently driver specific */ | |
251 | int pm_step; | |
252 | /* requested PM state value (S1, S2, S3, S4, ...) */ | |
253 | u32 pm_state; | |
254 | void* data; /* for driver use */ | |
255 | }; | |
256 | ||
257 | #include <linux/elevator.h> | |
258 | ||
165125e1 JA |
259 | typedef void (request_fn_proc) (struct request_queue *q); |
260 | typedef int (make_request_fn) (struct request_queue *q, struct bio *bio); | |
261 | typedef int (prep_rq_fn) (struct request_queue *, struct request *); | |
262 | typedef void (unplug_fn) (struct request_queue *); | |
1da177e4 LT |
263 | |
264 | struct bio_vec; | |
cc371e66 AK |
265 | struct bvec_merge_data { |
266 | struct block_device *bi_bdev; | |
267 | sector_t bi_sector; | |
268 | unsigned bi_size; | |
269 | unsigned long bi_rw; | |
270 | }; | |
271 | typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *, | |
272 | struct bio_vec *); | |
165125e1 | 273 | typedef void (prepare_flush_fn) (struct request_queue *, struct request *); |
ff856bad | 274 | typedef void (softirq_done_fn)(struct request *); |
2fb98e84 | 275 | typedef int (dma_drain_needed_fn)(struct request *); |
ef9e3fac | 276 | typedef int (lld_busy_fn) (struct request_queue *q); |
1da177e4 | 277 | |
242f9dcb JA |
278 | enum blk_eh_timer_return { |
279 | BLK_EH_NOT_HANDLED, | |
280 | BLK_EH_HANDLED, | |
281 | BLK_EH_RESET_TIMER, | |
282 | }; | |
283 | ||
284 | typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *); | |
285 | ||
1da177e4 LT |
286 | enum blk_queue_state { |
287 | Queue_down, | |
288 | Queue_up, | |
289 | }; | |
290 | ||
1da177e4 LT |
291 | struct blk_queue_tag { |
292 | struct request **tag_index; /* map of busy tags */ | |
293 | unsigned long *tag_map; /* bit map of free/busy tags */ | |
1da177e4 LT |
294 | int busy; /* current depth */ |
295 | int max_depth; /* what we will send to device */ | |
ba025082 | 296 | int real_max_depth; /* what the array can hold */ |
1da177e4 LT |
297 | atomic_t refcnt; /* map can be shared */ |
298 | }; | |
299 | ||
abf54393 FT |
300 | #define BLK_SCSI_MAX_CMDS (256) |
301 | #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8)) | |
302 | ||
025146e1 MP |
303 | struct queue_limits { |
304 | unsigned long bounce_pfn; | |
305 | unsigned long seg_boundary_mask; | |
306 | ||
307 | unsigned int max_hw_sectors; | |
308 | unsigned int max_sectors; | |
309 | unsigned int max_segment_size; | |
c72758f3 MP |
310 | unsigned int physical_block_size; |
311 | unsigned int alignment_offset; | |
312 | unsigned int io_min; | |
313 | unsigned int io_opt; | |
67efc925 | 314 | unsigned int max_discard_sectors; |
86b37281 MP |
315 | unsigned int discard_granularity; |
316 | unsigned int discard_alignment; | |
025146e1 MP |
317 | |
318 | unsigned short logical_block_size; | |
319 | unsigned short max_hw_segments; | |
320 | unsigned short max_phys_segments; | |
321 | ||
c72758f3 | 322 | unsigned char misaligned; |
86b37281 | 323 | unsigned char discard_misaligned; |
025146e1 | 324 | unsigned char no_cluster; |
98262f27 | 325 | signed char discard_zeroes_data; |
025146e1 MP |
326 | }; |
327 | ||
1da177e4 LT |
328 | struct request_queue |
329 | { | |
330 | /* | |
331 | * Together with queue_head for cacheline sharing | |
332 | */ | |
333 | struct list_head queue_head; | |
334 | struct request *last_merge; | |
b374d18a | 335 | struct elevator_queue *elevator; |
1da177e4 LT |
336 | |
337 | /* | |
338 | * the queue request freelist, one for reads and one for writes | |
339 | */ | |
340 | struct request_list rq; | |
341 | ||
342 | request_fn_proc *request_fn; | |
1da177e4 LT |
343 | make_request_fn *make_request_fn; |
344 | prep_rq_fn *prep_rq_fn; | |
345 | unplug_fn *unplug_fn; | |
346 | merge_bvec_fn *merge_bvec_fn; | |
1da177e4 | 347 | prepare_flush_fn *prepare_flush_fn; |
ff856bad | 348 | softirq_done_fn *softirq_done_fn; |
242f9dcb | 349 | rq_timed_out_fn *rq_timed_out_fn; |
2fb98e84 | 350 | dma_drain_needed_fn *dma_drain_needed; |
ef9e3fac | 351 | lld_busy_fn *lld_busy_fn; |
1da177e4 | 352 | |
8922e16c TH |
353 | /* |
354 | * Dispatch queue sorting | |
355 | */ | |
1b47f531 | 356 | sector_t end_sector; |
8922e16c | 357 | struct request *boundary_rq; |
8922e16c | 358 | |
1da177e4 LT |
359 | /* |
360 | * Auto-unplugging state | |
361 | */ | |
362 | struct timer_list unplug_timer; | |
363 | int unplug_thresh; /* After this many requests */ | |
364 | unsigned long unplug_delay; /* After this many jiffies */ | |
365 | struct work_struct unplug_work; | |
366 | ||
367 | struct backing_dev_info backing_dev_info; | |
368 | ||
369 | /* | |
370 | * The queue owner gets to use this for whatever they like. | |
371 | * ll_rw_blk doesn't touch it. | |
372 | */ | |
373 | void *queuedata; | |
374 | ||
1da177e4 LT |
375 | /* |
376 | * queue needs bounce pages for pages above this limit | |
377 | */ | |
8267e268 | 378 | gfp_t bounce_gfp; |
1da177e4 LT |
379 | |
380 | /* | |
381 | * various queue flags, see QUEUE_* below | |
382 | */ | |
383 | unsigned long queue_flags; | |
384 | ||
385 | /* | |
152587de JA |
386 | * protects queue structures from reentrancy. ->__queue_lock should |
387 | * _never_ be used directly, it is queue private. always use | |
388 | * ->queue_lock. | |
1da177e4 | 389 | */ |
152587de | 390 | spinlock_t __queue_lock; |
1da177e4 LT |
391 | spinlock_t *queue_lock; |
392 | ||
393 | /* | |
394 | * queue kobject | |
395 | */ | |
396 | struct kobject kobj; | |
397 | ||
398 | /* | |
399 | * queue settings | |
400 | */ | |
401 | unsigned long nr_requests; /* Max # of requests */ | |
402 | unsigned int nr_congestion_on; | |
403 | unsigned int nr_congestion_off; | |
404 | unsigned int nr_batching; | |
405 | ||
fa0ccd83 JB |
406 | void *dma_drain_buffer; |
407 | unsigned int dma_drain_size; | |
e3790c7d | 408 | unsigned int dma_pad_mask; |
1da177e4 LT |
409 | unsigned int dma_alignment; |
410 | ||
411 | struct blk_queue_tag *queue_tags; | |
6eca9004 | 412 | struct list_head tag_busy_list; |
1da177e4 | 413 | |
15853af9 | 414 | unsigned int nr_sorted; |
0a7ae2ff | 415 | unsigned int in_flight[2]; |
1da177e4 | 416 | |
242f9dcb JA |
417 | unsigned int rq_timeout; |
418 | struct timer_list timeout; | |
419 | struct list_head timeout_list; | |
420 | ||
025146e1 MP |
421 | struct queue_limits limits; |
422 | ||
1da177e4 LT |
423 | /* |
424 | * sg stuff | |
425 | */ | |
426 | unsigned int sg_timeout; | |
427 | unsigned int sg_reserved_size; | |
1946089a | 428 | int node; |
6c5c9341 | 429 | #ifdef CONFIG_BLK_DEV_IO_TRACE |
2056a782 | 430 | struct blk_trace *blk_trace; |
6c5c9341 | 431 | #endif |
1da177e4 LT |
432 | /* |
433 | * reserved for flush operations | |
434 | */ | |
797e7dbb TH |
435 | unsigned int ordered, next_ordered, ordseq; |
436 | int orderr, ordcolor; | |
437 | struct request pre_flush_rq, bar_rq, post_flush_rq; | |
438 | struct request *orig_bar_rq; | |
483f4afc AV |
439 | |
440 | struct mutex sysfs_lock; | |
d351af01 FT |
441 | |
442 | #if defined(CONFIG_BLK_DEV_BSG) | |
443 | struct bsg_class_device bsg_dev; | |
444 | #endif | |
1da177e4 LT |
445 | }; |
446 | ||
1da177e4 LT |
447 | #define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */ |
448 | #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ | |
449 | #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ | |
1faa16d2 JA |
450 | #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */ |
451 | #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */ | |
1da177e4 LT |
452 | #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ |
453 | #define QUEUE_FLAG_REENTER 6 /* Re-entrancy avoidance */ | |
454 | #define QUEUE_FLAG_PLUGGED 7 /* queue is plugged */ | |
64521d1a | 455 | #define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */ |
abae1fde | 456 | #define QUEUE_FLAG_BIDI 9 /* queue supports bidi requests */ |
ac9fafa1 | 457 | #define QUEUE_FLAG_NOMERGES 10 /* disable merge attempts */ |
c7c22e4d | 458 | #define QUEUE_FLAG_SAME_COMP 11 /* force complete on same CPU */ |
581d4e28 | 459 | #define QUEUE_FLAG_FAIL_IO 12 /* fake timeout */ |
4ee5eaf4 | 460 | #define QUEUE_FLAG_STACKABLE 13 /* supports request stacking */ |
a68bbddb | 461 | #define QUEUE_FLAG_NONROT 14 /* non-rotational device (SSD) */ |
88e740f1 | 462 | #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ |
bc58ba94 | 463 | #define QUEUE_FLAG_IO_STAT 15 /* do IO stats */ |
fb1e7538 | 464 | #define QUEUE_FLAG_CQ 16 /* hardware does queuing */ |
c15227de | 465 | #define QUEUE_FLAG_DISCARD 17 /* supports DISCARD */ |
bc58ba94 JA |
466 | |
467 | #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ | |
468 | (1 << QUEUE_FLAG_CLUSTER) | \ | |
01e97f6b JA |
469 | (1 << QUEUE_FLAG_STACKABLE) | \ |
470 | (1 << QUEUE_FLAG_SAME_COMP)) | |
797e7dbb | 471 | |
8f45c1a5 LT |
472 | static inline int queue_is_locked(struct request_queue *q) |
473 | { | |
7663c1e2 | 474 | #ifdef CONFIG_SMP |
8f45c1a5 LT |
475 | spinlock_t *lock = q->queue_lock; |
476 | return lock && spin_is_locked(lock); | |
7663c1e2 JA |
477 | #else |
478 | return 1; | |
479 | #endif | |
8f45c1a5 LT |
480 | } |
481 | ||
75ad23bc NP |
482 | static inline void queue_flag_set_unlocked(unsigned int flag, |
483 | struct request_queue *q) | |
484 | { | |
485 | __set_bit(flag, &q->queue_flags); | |
486 | } | |
487 | ||
e48ec690 JA |
488 | static inline int queue_flag_test_and_clear(unsigned int flag, |
489 | struct request_queue *q) | |
490 | { | |
491 | WARN_ON_ONCE(!queue_is_locked(q)); | |
492 | ||
493 | if (test_bit(flag, &q->queue_flags)) { | |
494 | __clear_bit(flag, &q->queue_flags); | |
495 | return 1; | |
496 | } | |
497 | ||
498 | return 0; | |
499 | } | |
500 | ||
501 | static inline int queue_flag_test_and_set(unsigned int flag, | |
502 | struct request_queue *q) | |
503 | { | |
504 | WARN_ON_ONCE(!queue_is_locked(q)); | |
505 | ||
506 | if (!test_bit(flag, &q->queue_flags)) { | |
507 | __set_bit(flag, &q->queue_flags); | |
508 | return 0; | |
509 | } | |
510 | ||
511 | return 1; | |
512 | } | |
513 | ||
75ad23bc NP |
514 | static inline void queue_flag_set(unsigned int flag, struct request_queue *q) |
515 | { | |
8f45c1a5 | 516 | WARN_ON_ONCE(!queue_is_locked(q)); |
75ad23bc NP |
517 | __set_bit(flag, &q->queue_flags); |
518 | } | |
519 | ||
520 | static inline void queue_flag_clear_unlocked(unsigned int flag, | |
521 | struct request_queue *q) | |
522 | { | |
523 | __clear_bit(flag, &q->queue_flags); | |
524 | } | |
525 | ||
0a7ae2ff JA |
526 | static inline int queue_in_flight(struct request_queue *q) |
527 | { | |
528 | return q->in_flight[0] + q->in_flight[1]; | |
529 | } | |
530 | ||
75ad23bc NP |
531 | static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) |
532 | { | |
8f45c1a5 | 533 | WARN_ON_ONCE(!queue_is_locked(q)); |
75ad23bc NP |
534 | __clear_bit(flag, &q->queue_flags); |
535 | } | |
536 | ||
797e7dbb TH |
537 | enum { |
538 | /* | |
539 | * Hardbarrier is supported with one of the following methods. | |
540 | * | |
541 | * NONE : hardbarrier unsupported | |
542 | * DRAIN : ordering by draining is enough | |
543 | * DRAIN_FLUSH : ordering by draining w/ pre and post flushes | |
544 | * DRAIN_FUA : ordering by draining w/ pre flush and FUA write | |
545 | * TAG : ordering by tag is enough | |
546 | * TAG_FLUSH : ordering by tag w/ pre and post flushes | |
547 | * TAG_FUA : ordering by tag w/ pre flush and FUA write | |
548 | */ | |
313e4299 TH |
549 | QUEUE_ORDERED_BY_DRAIN = 0x01, |
550 | QUEUE_ORDERED_BY_TAG = 0x02, | |
551 | QUEUE_ORDERED_DO_PREFLUSH = 0x10, | |
f671620e | 552 | QUEUE_ORDERED_DO_BAR = 0x20, |
313e4299 TH |
553 | QUEUE_ORDERED_DO_POSTFLUSH = 0x40, |
554 | QUEUE_ORDERED_DO_FUA = 0x80, | |
555 | ||
556 | QUEUE_ORDERED_NONE = 0x00, | |
557 | ||
f671620e TH |
558 | QUEUE_ORDERED_DRAIN = QUEUE_ORDERED_BY_DRAIN | |
559 | QUEUE_ORDERED_DO_BAR, | |
313e4299 TH |
560 | QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN | |
561 | QUEUE_ORDERED_DO_PREFLUSH | | |
562 | QUEUE_ORDERED_DO_POSTFLUSH, | |
563 | QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN | | |
564 | QUEUE_ORDERED_DO_PREFLUSH | | |
565 | QUEUE_ORDERED_DO_FUA, | |
566 | ||
f671620e TH |
567 | QUEUE_ORDERED_TAG = QUEUE_ORDERED_BY_TAG | |
568 | QUEUE_ORDERED_DO_BAR, | |
313e4299 TH |
569 | QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG | |
570 | QUEUE_ORDERED_DO_PREFLUSH | | |
571 | QUEUE_ORDERED_DO_POSTFLUSH, | |
572 | QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG | | |
573 | QUEUE_ORDERED_DO_PREFLUSH | | |
574 | QUEUE_ORDERED_DO_FUA, | |
797e7dbb TH |
575 | |
576 | /* | |
577 | * Ordered operation sequence | |
578 | */ | |
579 | QUEUE_ORDSEQ_STARTED = 0x01, /* flushing in progress */ | |
580 | QUEUE_ORDSEQ_DRAIN = 0x02, /* waiting for the queue to be drained */ | |
581 | QUEUE_ORDSEQ_PREFLUSH = 0x04, /* pre-flushing in progress */ | |
582 | QUEUE_ORDSEQ_BAR = 0x08, /* original barrier req in progress */ | |
583 | QUEUE_ORDSEQ_POSTFLUSH = 0x10, /* post-flushing in progress */ | |
584 | QUEUE_ORDSEQ_DONE = 0x20, | |
585 | }; | |
1da177e4 LT |
586 | |
587 | #define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags) | |
588 | #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) | |
fb1e7538 | 589 | #define blk_queue_queuing(q) test_bit(QUEUE_FLAG_CQ, &(q)->queue_flags) |
1da177e4 | 590 | #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) |
ac9fafa1 | 591 | #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) |
a68bbddb | 592 | #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) |
bc58ba94 | 593 | #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags) |
797e7dbb | 594 | #define blk_queue_flushing(q) ((q)->ordseq) |
4ee5eaf4 KU |
595 | #define blk_queue_stackable(q) \ |
596 | test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags) | |
c15227de | 597 | #define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags) |
1da177e4 | 598 | |
4aff5e23 JA |
599 | #define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS) |
600 | #define blk_pc_request(rq) ((rq)->cmd_type == REQ_TYPE_BLOCK_PC) | |
601 | #define blk_special_request(rq) ((rq)->cmd_type == REQ_TYPE_SPECIAL) | |
602 | #define blk_sense_request(rq) ((rq)->cmd_type == REQ_TYPE_SENSE) | |
603 | ||
6000a368 MC |
604 | #define blk_failfast_dev(rq) ((rq)->cmd_flags & REQ_FAILFAST_DEV) |
605 | #define blk_failfast_transport(rq) ((rq)->cmd_flags & REQ_FAILFAST_TRANSPORT) | |
606 | #define blk_failfast_driver(rq) ((rq)->cmd_flags & REQ_FAILFAST_DRIVER) | |
607 | #define blk_noretry_request(rq) (blk_failfast_dev(rq) || \ | |
608 | blk_failfast_transport(rq) || \ | |
609 | blk_failfast_driver(rq)) | |
4aff5e23 | 610 | #define blk_rq_started(rq) ((rq)->cmd_flags & REQ_STARTED) |
42dad764 | 611 | #define blk_rq_io_stat(rq) ((rq)->cmd_flags & REQ_IO_STAT) |
96c16743 | 612 | #define blk_rq_quiet(rq) ((rq)->cmd_flags & REQ_QUIET) |
1da177e4 | 613 | |
e17fc0a1 | 614 | #define blk_account_rq(rq) (blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq))) |
1da177e4 | 615 | |
4aff5e23 JA |
616 | #define blk_pm_suspend_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND) |
617 | #define blk_pm_resume_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_RESUME) | |
1da177e4 | 618 | #define blk_pm_request(rq) \ |
4aff5e23 | 619 | (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq)) |
1da177e4 | 620 | |
ab780f1e | 621 | #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1) |
4aff5e23 JA |
622 | #define blk_sorted_rq(rq) ((rq)->cmd_flags & REQ_SORTED) |
623 | #define blk_barrier_rq(rq) ((rq)->cmd_flags & REQ_HARDBARRIER) | |
624 | #define blk_fua_rq(rq) ((rq)->cmd_flags & REQ_FUA) | |
fb2dce86 | 625 | #define blk_discard_rq(rq) ((rq)->cmd_flags & REQ_DISCARD) |
abae1fde | 626 | #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) |
336cdb40 KU |
627 | /* rq->queuelist of dequeued request must be list_empty() */ |
628 | #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) | |
1da177e4 LT |
629 | |
630 | #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) | |
631 | ||
4aff5e23 | 632 | #define rq_data_dir(rq) ((rq)->cmd_flags & 1) |
1da177e4 | 633 | |
9e2585a8 | 634 | /* |
1faa16d2 | 635 | * We regard a request as sync, if either a read or a sync write |
9e2585a8 | 636 | */ |
1faa16d2 JA |
637 | static inline bool rw_is_sync(unsigned int rw_flags) |
638 | { | |
639 | return !(rw_flags & REQ_RW) || (rw_flags & REQ_RW_SYNC); | |
640 | } | |
641 | ||
642 | static inline bool rq_is_sync(struct request *rq) | |
643 | { | |
644 | return rw_is_sync(rq->cmd_flags); | |
645 | } | |
646 | ||
5404bc7a | 647 | #define rq_is_meta(rq) ((rq)->cmd_flags & REQ_RW_META) |
aeb6fafb | 648 | #define rq_noidle(rq) ((rq)->cmd_flags & REQ_NOIDLE) |
9e2585a8 | 649 | |
1faa16d2 | 650 | static inline int blk_queue_full(struct request_queue *q, int sync) |
1da177e4 | 651 | { |
1faa16d2 JA |
652 | if (sync) |
653 | return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags); | |
654 | return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags); | |
1da177e4 LT |
655 | } |
656 | ||
1faa16d2 | 657 | static inline void blk_set_queue_full(struct request_queue *q, int sync) |
1da177e4 | 658 | { |
1faa16d2 JA |
659 | if (sync) |
660 | queue_flag_set(QUEUE_FLAG_SYNCFULL, q); | |
1da177e4 | 661 | else |
1faa16d2 | 662 | queue_flag_set(QUEUE_FLAG_ASYNCFULL, q); |
1da177e4 LT |
663 | } |
664 | ||
1faa16d2 | 665 | static inline void blk_clear_queue_full(struct request_queue *q, int sync) |
1da177e4 | 666 | { |
1faa16d2 JA |
667 | if (sync) |
668 | queue_flag_clear(QUEUE_FLAG_SYNCFULL, q); | |
1da177e4 | 669 | else |
1faa16d2 | 670 | queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q); |
1da177e4 LT |
671 | } |
672 | ||
673 | ||
674 | /* | |
675 | * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may | |
676 | * it already be started by driver. | |
677 | */ | |
678 | #define RQ_NOMERGE_FLAGS \ | |
679 | (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER) | |
680 | #define rq_mergeable(rq) \ | |
e17fc0a1 DW |
681 | (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \ |
682 | (blk_discard_rq(rq) || blk_fs_request((rq)))) | |
1da177e4 | 683 | |
1da177e4 LT |
684 | /* |
685 | * q->prep_rq_fn return values | |
686 | */ | |
687 | #define BLKPREP_OK 0 /* serve it */ | |
688 | #define BLKPREP_KILL 1 /* fatal error, kill */ | |
689 | #define BLKPREP_DEFER 2 /* leave on queue */ | |
690 | ||
691 | extern unsigned long blk_max_low_pfn, blk_max_pfn; | |
692 | ||
693 | /* | |
694 | * standard bounce addresses: | |
695 | * | |
696 | * BLK_BOUNCE_HIGH : bounce all highmem pages | |
697 | * BLK_BOUNCE_ANY : don't bounce anything | |
698 | * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary | |
699 | */ | |
2472892a AK |
700 | |
701 | #if BITS_PER_LONG == 32 | |
1da177e4 | 702 | #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) |
2472892a AK |
703 | #else |
704 | #define BLK_BOUNCE_HIGH -1ULL | |
705 | #endif | |
706 | #define BLK_BOUNCE_ANY (-1ULL) | |
1da177e4 LT |
707 | #define BLK_BOUNCE_ISA (ISA_DMA_THRESHOLD) |
708 | ||
3d6392cf JA |
709 | /* |
710 | * default timeout for SG_IO if none specified | |
711 | */ | |
712 | #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) | |
f2f1fa78 | 713 | #define BLK_MIN_SG_TIMEOUT (7 * HZ) |
3d6392cf | 714 | |
2a7326b5 | 715 | #ifdef CONFIG_BOUNCE |
1da177e4 | 716 | extern int init_emergency_isa_pool(void); |
165125e1 | 717 | extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); |
1da177e4 LT |
718 | #else |
719 | static inline int init_emergency_isa_pool(void) | |
720 | { | |
721 | return 0; | |
722 | } | |
165125e1 | 723 | static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) |
1da177e4 LT |
724 | { |
725 | } | |
726 | #endif /* CONFIG_MMU */ | |
727 | ||
152e283f FT |
728 | struct rq_map_data { |
729 | struct page **pages; | |
730 | int page_order; | |
731 | int nr_entries; | |
56c451f4 | 732 | unsigned long offset; |
97ae77a1 | 733 | int null_mapped; |
ecb554a8 | 734 | int from_user; |
152e283f FT |
735 | }; |
736 | ||
5705f702 N |
737 | struct req_iterator { |
738 | int i; | |
739 | struct bio *bio; | |
740 | }; | |
741 | ||
742 | /* This should not be used directly - use rq_for_each_segment */ | |
1e428079 JA |
743 | #define for_each_bio(_bio) \ |
744 | for (; _bio; _bio = _bio->bi_next) | |
5705f702 | 745 | #define __rq_for_each_bio(_bio, rq) \ |
1da177e4 LT |
746 | if ((rq->bio)) \ |
747 | for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) | |
748 | ||
5705f702 N |
749 | #define rq_for_each_segment(bvl, _rq, _iter) \ |
750 | __rq_for_each_bio(_iter.bio, _rq) \ | |
751 | bio_for_each_segment(bvl, _iter.bio, _iter.i) | |
752 | ||
753 | #define rq_iter_last(rq, _iter) \ | |
754 | (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1) | |
755 | ||
2d4dc890 IL |
756 | #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE |
757 | # error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform" | |
758 | #endif | |
759 | #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE | |
760 | extern void rq_flush_dcache_pages(struct request *rq); | |
761 | #else | |
762 | static inline void rq_flush_dcache_pages(struct request *rq) | |
763 | { | |
764 | } | |
765 | #endif | |
766 | ||
1da177e4 LT |
767 | extern int blk_register_queue(struct gendisk *disk); |
768 | extern void blk_unregister_queue(struct gendisk *disk); | |
769 | extern void register_disk(struct gendisk *dev); | |
770 | extern void generic_make_request(struct bio *bio); | |
2a4aa30c | 771 | extern void blk_rq_init(struct request_queue *q, struct request *rq); |
1da177e4 | 772 | extern void blk_put_request(struct request *); |
165125e1 | 773 | extern void __blk_put_request(struct request_queue *, struct request *); |
165125e1 | 774 | extern struct request *blk_get_request(struct request_queue *, int, gfp_t); |
79eb63e9 BH |
775 | extern struct request *blk_make_request(struct request_queue *, struct bio *, |
776 | gfp_t); | |
165125e1 JA |
777 | extern void blk_insert_request(struct request_queue *, struct request *, int, void *); |
778 | extern void blk_requeue_request(struct request_queue *, struct request *); | |
82124d60 | 779 | extern int blk_rq_check_limits(struct request_queue *q, struct request *rq); |
ef9e3fac | 780 | extern int blk_lld_busy(struct request_queue *q); |
b0fd271d KU |
781 | extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src, |
782 | struct bio_set *bs, gfp_t gfp_mask, | |
783 | int (*bio_ctr)(struct bio *, struct bio *, void *), | |
784 | void *data); | |
785 | extern void blk_rq_unprep_clone(struct request *rq); | |
82124d60 KU |
786 | extern int blk_insert_cloned_request(struct request_queue *q, |
787 | struct request *rq); | |
165125e1 | 788 | extern void blk_plug_device(struct request_queue *); |
6c5e0c4d | 789 | extern void blk_plug_device_unlocked(struct request_queue *); |
165125e1 JA |
790 | extern int blk_remove_plug(struct request_queue *); |
791 | extern void blk_recount_segments(struct request_queue *, struct bio *); | |
74f3c8af AV |
792 | extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t, |
793 | unsigned int, void __user *); | |
e915e872 AV |
794 | extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t, |
795 | struct scsi_ioctl_command __user *); | |
3fcfab16 AM |
796 | |
797 | /* | |
798 | * A queue has just exitted congestion. Note this in the global counter of | |
799 | * congested queues, and wake up anyone who was waiting for requests to be | |
800 | * put back. | |
801 | */ | |
8aa7e847 | 802 | static inline void blk_clear_queue_congested(struct request_queue *q, int sync) |
3fcfab16 | 803 | { |
8aa7e847 | 804 | clear_bdi_congested(&q->backing_dev_info, sync); |
3fcfab16 AM |
805 | } |
806 | ||
807 | /* | |
808 | * A queue has just entered congestion. Flag that in the queue's VM-visible | |
809 | * state flags and increment the global gounter of congested queues. | |
810 | */ | |
8aa7e847 | 811 | static inline void blk_set_queue_congested(struct request_queue *q, int sync) |
3fcfab16 | 812 | { |
8aa7e847 | 813 | set_bdi_congested(&q->backing_dev_info, sync); |
3fcfab16 AM |
814 | } |
815 | ||
165125e1 JA |
816 | extern void blk_start_queue(struct request_queue *q); |
817 | extern void blk_stop_queue(struct request_queue *q); | |
1da177e4 | 818 | extern void blk_sync_queue(struct request_queue *q); |
165125e1 | 819 | extern void __blk_stop_queue(struct request_queue *q); |
75ad23bc | 820 | extern void __blk_run_queue(struct request_queue *); |
165125e1 | 821 | extern void blk_run_queue(struct request_queue *); |
a3bce90e | 822 | extern int blk_rq_map_user(struct request_queue *, struct request *, |
152e283f FT |
823 | struct rq_map_data *, void __user *, unsigned long, |
824 | gfp_t); | |
8e5cfc45 | 825 | extern int blk_rq_unmap_user(struct bio *); |
165125e1 JA |
826 | extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); |
827 | extern int blk_rq_map_user_iov(struct request_queue *, struct request *, | |
152e283f FT |
828 | struct rq_map_data *, struct sg_iovec *, int, |
829 | unsigned int, gfp_t); | |
165125e1 | 830 | extern int blk_execute_rq(struct request_queue *, struct gendisk *, |
994ca9a1 | 831 | struct request *, int); |
165125e1 | 832 | extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, |
15fc858a | 833 | struct request *, int, rq_end_io_fn *); |
2ad8b1ef | 834 | extern void blk_unplug(struct request_queue *q); |
6e39b69e | 835 | |
165125e1 | 836 | static inline struct request_queue *bdev_get_queue(struct block_device *bdev) |
1da177e4 LT |
837 | { |
838 | return bdev->bd_disk->queue; | |
839 | } | |
840 | ||
5efccd17 | 841 | /* |
80a761fd TH |
842 | * blk_rq_pos() : the current sector |
843 | * blk_rq_bytes() : bytes left in the entire request | |
844 | * blk_rq_cur_bytes() : bytes left in the current segment | |
845 | * blk_rq_err_bytes() : bytes left till the next error boundary | |
846 | * blk_rq_sectors() : sectors left in the entire request | |
847 | * blk_rq_cur_sectors() : sectors left in the current segment | |
5efccd17 | 848 | */ |
5b93629b TH |
849 | static inline sector_t blk_rq_pos(const struct request *rq) |
850 | { | |
a2dec7b3 | 851 | return rq->__sector; |
2e46e8b2 TH |
852 | } |
853 | ||
854 | static inline unsigned int blk_rq_bytes(const struct request *rq) | |
855 | { | |
a2dec7b3 | 856 | return rq->__data_len; |
5b93629b TH |
857 | } |
858 | ||
2e46e8b2 TH |
859 | static inline int blk_rq_cur_bytes(const struct request *rq) |
860 | { | |
861 | return rq->bio ? bio_cur_bytes(rq->bio) : 0; | |
862 | } | |
5efccd17 | 863 | |
80a761fd TH |
864 | extern unsigned int blk_rq_err_bytes(const struct request *rq); |
865 | ||
5b93629b TH |
866 | static inline unsigned int blk_rq_sectors(const struct request *rq) |
867 | { | |
2e46e8b2 | 868 | return blk_rq_bytes(rq) >> 9; |
5b93629b TH |
869 | } |
870 | ||
871 | static inline unsigned int blk_rq_cur_sectors(const struct request *rq) | |
872 | { | |
2e46e8b2 | 873 | return blk_rq_cur_bytes(rq) >> 9; |
5b93629b TH |
874 | } |
875 | ||
9934c8c0 TH |
876 | /* |
877 | * Request issue related functions. | |
878 | */ | |
879 | extern struct request *blk_peek_request(struct request_queue *q); | |
880 | extern void blk_start_request(struct request *rq); | |
881 | extern struct request *blk_fetch_request(struct request_queue *q); | |
882 | ||
1da177e4 | 883 | /* |
2e60e022 TH |
884 | * Request completion related functions. |
885 | * | |
886 | * blk_update_request() completes given number of bytes and updates | |
887 | * the request without completing it. | |
888 | * | |
f06d9a2b TH |
889 | * blk_end_request() and friends. __blk_end_request() must be called |
890 | * with the request queue spinlock acquired. | |
1da177e4 LT |
891 | * |
892 | * Several drivers define their own end_request and call | |
3bcddeac KU |
893 | * blk_end_request() for parts of the original function. |
894 | * This prevents code duplication in drivers. | |
1da177e4 | 895 | */ |
2e60e022 TH |
896 | extern bool blk_update_request(struct request *rq, int error, |
897 | unsigned int nr_bytes); | |
b1f74493 FT |
898 | extern bool blk_end_request(struct request *rq, int error, |
899 | unsigned int nr_bytes); | |
900 | extern void blk_end_request_all(struct request *rq, int error); | |
901 | extern bool blk_end_request_cur(struct request *rq, int error); | |
80a761fd | 902 | extern bool blk_end_request_err(struct request *rq, int error); |
b1f74493 FT |
903 | extern bool __blk_end_request(struct request *rq, int error, |
904 | unsigned int nr_bytes); | |
905 | extern void __blk_end_request_all(struct request *rq, int error); | |
906 | extern bool __blk_end_request_cur(struct request *rq, int error); | |
80a761fd | 907 | extern bool __blk_end_request_err(struct request *rq, int error); |
2e60e022 | 908 | |
ff856bad | 909 | extern void blk_complete_request(struct request *); |
242f9dcb JA |
910 | extern void __blk_complete_request(struct request *); |
911 | extern void blk_abort_request(struct request *); | |
11914a53 | 912 | extern void blk_abort_queue(struct request_queue *); |
ff856bad | 913 | |
1da177e4 LT |
914 | /* |
915 | * Access functions for manipulating queue properties | |
916 | */ | |
165125e1 | 917 | extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, |
1946089a | 918 | spinlock_t *lock, int node_id); |
165125e1 JA |
919 | extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); |
920 | extern void blk_cleanup_queue(struct request_queue *); | |
921 | extern void blk_queue_make_request(struct request_queue *, make_request_fn *); | |
922 | extern void blk_queue_bounce_limit(struct request_queue *, u64); | |
923 | extern void blk_queue_max_sectors(struct request_queue *, unsigned int); | |
ae03bf63 | 924 | extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int); |
165125e1 JA |
925 | extern void blk_queue_max_phys_segments(struct request_queue *, unsigned short); |
926 | extern void blk_queue_max_hw_segments(struct request_queue *, unsigned short); | |
927 | extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); | |
67efc925 CH |
928 | extern void blk_queue_max_discard_sectors(struct request_queue *q, |
929 | unsigned int max_discard_sectors); | |
e1defc4f | 930 | extern void blk_queue_logical_block_size(struct request_queue *, unsigned short); |
c72758f3 MP |
931 | extern void blk_queue_physical_block_size(struct request_queue *, unsigned short); |
932 | extern void blk_queue_alignment_offset(struct request_queue *q, | |
933 | unsigned int alignment); | |
7c958e32 | 934 | extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min); |
c72758f3 | 935 | extern void blk_queue_io_min(struct request_queue *q, unsigned int min); |
3c5820c7 | 936 | extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt); |
c72758f3 | 937 | extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); |
e475bba2 | 938 | extern void blk_set_default_limits(struct queue_limits *lim); |
c72758f3 MP |
939 | extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, |
940 | sector_t offset); | |
941 | extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, | |
942 | sector_t offset); | |
165125e1 | 943 | extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); |
e3790c7d | 944 | extern void blk_queue_dma_pad(struct request_queue *, unsigned int); |
27f8221a | 945 | extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); |
2fb98e84 TH |
946 | extern int blk_queue_dma_drain(struct request_queue *q, |
947 | dma_drain_needed_fn *dma_drain_needed, | |
948 | void *buf, unsigned int size); | |
ef9e3fac | 949 | extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn); |
165125e1 JA |
950 | extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); |
951 | extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); | |
952 | extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); | |
953 | extern void blk_queue_dma_alignment(struct request_queue *, int); | |
11c3e689 | 954 | extern void blk_queue_update_dma_alignment(struct request_queue *, int); |
165125e1 | 955 | extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); |
242f9dcb JA |
956 | extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *); |
957 | extern void blk_queue_rq_timeout(struct request_queue *, unsigned int); | |
1da177e4 | 958 | extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); |
165125e1 | 959 | extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *); |
8f11b3e9 | 960 | extern bool blk_do_ordered(struct request_queue *, struct request **); |
165125e1 | 961 | extern unsigned blk_ordered_cur_seq(struct request_queue *); |
797e7dbb | 962 | extern unsigned blk_ordered_req_seq(struct request *); |
8f11b3e9 | 963 | extern bool blk_ordered_complete_seq(struct request_queue *, unsigned, int); |
1da177e4 | 964 | |
165125e1 | 965 | extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); |
1da177e4 | 966 | extern void blk_dump_rq_flags(struct request *, char *); |
165125e1 | 967 | extern void generic_unplug_device(struct request_queue *); |
1da177e4 | 968 | extern long nr_blockdev_pages(void); |
1da177e4 | 969 | |
165125e1 JA |
970 | int blk_get_queue(struct request_queue *); |
971 | struct request_queue *blk_alloc_queue(gfp_t); | |
972 | struct request_queue *blk_alloc_queue_node(gfp_t, int); | |
973 | extern void blk_put_queue(struct request_queue *); | |
1da177e4 LT |
974 | |
975 | /* | |
976 | * tag stuff | |
977 | */ | |
4aff5e23 | 978 | #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED) |
165125e1 JA |
979 | extern int blk_queue_start_tag(struct request_queue *, struct request *); |
980 | extern struct request *blk_queue_find_tag(struct request_queue *, int); | |
981 | extern void blk_queue_end_tag(struct request_queue *, struct request *); | |
982 | extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *); | |
983 | extern void blk_queue_free_tags(struct request_queue *); | |
984 | extern int blk_queue_resize_tags(struct request_queue *, int); | |
985 | extern void blk_queue_invalidate_tags(struct request_queue *); | |
492dfb48 JB |
986 | extern struct blk_queue_tag *blk_init_tags(int); |
987 | extern void blk_free_tags(struct blk_queue_tag *); | |
1da177e4 | 988 | |
f583f492 DS |
989 | static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, |
990 | int tag) | |
991 | { | |
992 | if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) | |
993 | return NULL; | |
994 | return bqt->tag_index[tag]; | |
995 | } | |
996 | ||
1da177e4 | 997 | extern int blkdev_issue_flush(struct block_device *, sector_t *); |
746cd1e7 CH |
998 | #define DISCARD_FL_WAIT 0x01 /* wait for completion */ |
999 | #define DISCARD_FL_BARRIER 0x02 /* issue DISCARD_BARRIER request */ | |
1000 | extern int blkdev_issue_discard(struct block_device *, sector_t sector, | |
1001 | sector_t nr_sects, gfp_t, int flags); | |
fb2dce86 DW |
1002 | |
1003 | static inline int sb_issue_discard(struct super_block *sb, | |
3e6053d7 | 1004 | sector_t block, sector_t nr_blocks) |
fb2dce86 DW |
1005 | { |
1006 | block <<= (sb->s_blocksize_bits - 9); | |
1007 | nr_blocks <<= (sb->s_blocksize_bits - 9); | |
746cd1e7 CH |
1008 | return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_KERNEL, |
1009 | DISCARD_FL_BARRIER); | |
fb2dce86 | 1010 | } |
1da177e4 | 1011 | |
018e0446 | 1012 | extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm); |
0b07de85 | 1013 | |
1da177e4 LT |
1014 | #define MAX_PHYS_SEGMENTS 128 |
1015 | #define MAX_HW_SEGMENTS 128 | |
defd94b7 MC |
1016 | #define SAFE_MAX_SECTORS 255 |
1017 | #define BLK_DEF_MAX_SECTORS 1024 | |
1da177e4 LT |
1018 | |
1019 | #define MAX_SEGMENT_SIZE 65536 | |
1020 | ||
0e435ac2 MB |
1021 | #define BLK_SEG_BOUNDARY_MASK 0xFFFFFFFFUL |
1022 | ||
1da177e4 LT |
1023 | #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) |
1024 | ||
ae03bf63 MP |
1025 | static inline unsigned long queue_bounce_pfn(struct request_queue *q) |
1026 | { | |
025146e1 | 1027 | return q->limits.bounce_pfn; |
ae03bf63 MP |
1028 | } |
1029 | ||
1030 | static inline unsigned long queue_segment_boundary(struct request_queue *q) | |
1031 | { | |
025146e1 | 1032 | return q->limits.seg_boundary_mask; |
ae03bf63 MP |
1033 | } |
1034 | ||
1035 | static inline unsigned int queue_max_sectors(struct request_queue *q) | |
1036 | { | |
025146e1 | 1037 | return q->limits.max_sectors; |
ae03bf63 MP |
1038 | } |
1039 | ||
1040 | static inline unsigned int queue_max_hw_sectors(struct request_queue *q) | |
1041 | { | |
025146e1 | 1042 | return q->limits.max_hw_sectors; |
ae03bf63 MP |
1043 | } |
1044 | ||
1045 | static inline unsigned short queue_max_hw_segments(struct request_queue *q) | |
1046 | { | |
025146e1 | 1047 | return q->limits.max_hw_segments; |
ae03bf63 MP |
1048 | } |
1049 | ||
1050 | static inline unsigned short queue_max_phys_segments(struct request_queue *q) | |
1051 | { | |
025146e1 | 1052 | return q->limits.max_phys_segments; |
ae03bf63 MP |
1053 | } |
1054 | ||
1055 | static inline unsigned int queue_max_segment_size(struct request_queue *q) | |
1056 | { | |
025146e1 | 1057 | return q->limits.max_segment_size; |
ae03bf63 MP |
1058 | } |
1059 | ||
e1defc4f | 1060 | static inline unsigned short queue_logical_block_size(struct request_queue *q) |
1da177e4 LT |
1061 | { |
1062 | int retval = 512; | |
1063 | ||
025146e1 MP |
1064 | if (q && q->limits.logical_block_size) |
1065 | retval = q->limits.logical_block_size; | |
1da177e4 LT |
1066 | |
1067 | return retval; | |
1068 | } | |
1069 | ||
e1defc4f | 1070 | static inline unsigned short bdev_logical_block_size(struct block_device *bdev) |
1da177e4 | 1071 | { |
e1defc4f | 1072 | return queue_logical_block_size(bdev_get_queue(bdev)); |
1da177e4 LT |
1073 | } |
1074 | ||
c72758f3 MP |
1075 | static inline unsigned int queue_physical_block_size(struct request_queue *q) |
1076 | { | |
1077 | return q->limits.physical_block_size; | |
1078 | } | |
1079 | ||
ac481c20 MP |
1080 | static inline int bdev_physical_block_size(struct block_device *bdev) |
1081 | { | |
1082 | return queue_physical_block_size(bdev_get_queue(bdev)); | |
1083 | } | |
1084 | ||
c72758f3 MP |
1085 | static inline unsigned int queue_io_min(struct request_queue *q) |
1086 | { | |
1087 | return q->limits.io_min; | |
1088 | } | |
1089 | ||
ac481c20 MP |
1090 | static inline int bdev_io_min(struct block_device *bdev) |
1091 | { | |
1092 | return queue_io_min(bdev_get_queue(bdev)); | |
1093 | } | |
1094 | ||
c72758f3 MP |
1095 | static inline unsigned int queue_io_opt(struct request_queue *q) |
1096 | { | |
1097 | return q->limits.io_opt; | |
1098 | } | |
1099 | ||
ac481c20 MP |
1100 | static inline int bdev_io_opt(struct block_device *bdev) |
1101 | { | |
1102 | return queue_io_opt(bdev_get_queue(bdev)); | |
1103 | } | |
1104 | ||
c72758f3 MP |
1105 | static inline int queue_alignment_offset(struct request_queue *q) |
1106 | { | |
ac481c20 | 1107 | if (q->limits.misaligned) |
c72758f3 MP |
1108 | return -1; |
1109 | ||
ac481c20 | 1110 | return q->limits.alignment_offset; |
c72758f3 MP |
1111 | } |
1112 | ||
81744ee4 MP |
1113 | static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t offset) |
1114 | { | |
1115 | unsigned int granularity = max(lim->physical_block_size, lim->io_min); | |
1116 | ||
1117 | offset &= granularity - 1; | |
1118 | return (granularity + lim->alignment_offset - offset) & (granularity - 1); | |
1119 | } | |
1120 | ||
c72758f3 MP |
1121 | static inline int queue_sector_alignment_offset(struct request_queue *q, |
1122 | sector_t sector) | |
1123 | { | |
81744ee4 | 1124 | return queue_limit_alignment_offset(&q->limits, sector << 9); |
c72758f3 MP |
1125 | } |
1126 | ||
ac481c20 MP |
1127 | static inline int bdev_alignment_offset(struct block_device *bdev) |
1128 | { | |
1129 | struct request_queue *q = bdev_get_queue(bdev); | |
1130 | ||
1131 | if (q->limits.misaligned) | |
1132 | return -1; | |
1133 | ||
1134 | if (bdev != bdev->bd_contains) | |
1135 | return bdev->bd_part->alignment_offset; | |
1136 | ||
1137 | return q->limits.alignment_offset; | |
1138 | } | |
1139 | ||
86b37281 MP |
1140 | static inline int queue_discard_alignment(struct request_queue *q) |
1141 | { | |
1142 | if (q->limits.discard_misaligned) | |
1143 | return -1; | |
1144 | ||
1145 | return q->limits.discard_alignment; | |
1146 | } | |
1147 | ||
1148 | static inline int queue_sector_discard_alignment(struct request_queue *q, | |
1149 | sector_t sector) | |
1150 | { | |
1151 | return ((sector << 9) - q->limits.discard_alignment) | |
1152 | & (q->limits.discard_granularity - 1); | |
1153 | } | |
1154 | ||
98262f27 MP |
1155 | static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) |
1156 | { | |
1157 | if (q->limits.discard_zeroes_data == 1) | |
1158 | return 1; | |
1159 | ||
1160 | return 0; | |
1161 | } | |
1162 | ||
1163 | static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev) | |
1164 | { | |
1165 | return queue_discard_zeroes_data(bdev_get_queue(bdev)); | |
1166 | } | |
1167 | ||
165125e1 | 1168 | static inline int queue_dma_alignment(struct request_queue *q) |
1da177e4 | 1169 | { |
482eb689 | 1170 | return q ? q->dma_alignment : 511; |
1da177e4 LT |
1171 | } |
1172 | ||
87904074 FT |
1173 | static inline int blk_rq_aligned(struct request_queue *q, void *addr, |
1174 | unsigned int len) | |
1175 | { | |
1176 | unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask; | |
1177 | return !((unsigned long)addr & alignment) && !(len & alignment); | |
1178 | } | |
1179 | ||
1da177e4 LT |
1180 | /* assumes size > 256 */ |
1181 | static inline unsigned int blksize_bits(unsigned int size) | |
1182 | { | |
1183 | unsigned int bits = 8; | |
1184 | do { | |
1185 | bits++; | |
1186 | size >>= 1; | |
1187 | } while (size > 256); | |
1188 | return bits; | |
1189 | } | |
1190 | ||
2befb9e3 | 1191 | static inline unsigned int block_size(struct block_device *bdev) |
1da177e4 LT |
1192 | { |
1193 | return bdev->bd_block_size; | |
1194 | } | |
1195 | ||
1196 | typedef struct {struct page *v;} Sector; | |
1197 | ||
1198 | unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); | |
1199 | ||
1200 | static inline void put_dev_sector(Sector p) | |
1201 | { | |
1202 | page_cache_release(p.v); | |
1203 | } | |
1204 | ||
1205 | struct work_struct; | |
18887ad9 | 1206 | int kblockd_schedule_work(struct request_queue *q, struct work_struct *work); |
1da177e4 | 1207 | |
1da177e4 LT |
1208 | #define MODULE_ALIAS_BLOCKDEV(major,minor) \ |
1209 | MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) | |
1210 | #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ | |
1211 | MODULE_ALIAS("block-major-" __stringify(major) "-*") | |
1212 | ||
7ba1ba12 MP |
1213 | #if defined(CONFIG_BLK_DEV_INTEGRITY) |
1214 | ||
b24498d4 JA |
1215 | #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */ |
1216 | #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */ | |
7ba1ba12 MP |
1217 | |
1218 | struct blk_integrity_exchg { | |
1219 | void *prot_buf; | |
1220 | void *data_buf; | |
1221 | sector_t sector; | |
1222 | unsigned int data_size; | |
1223 | unsigned short sector_size; | |
1224 | const char *disk_name; | |
1225 | }; | |
1226 | ||
1227 | typedef void (integrity_gen_fn) (struct blk_integrity_exchg *); | |
1228 | typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *); | |
1229 | typedef void (integrity_set_tag_fn) (void *, void *, unsigned int); | |
1230 | typedef void (integrity_get_tag_fn) (void *, void *, unsigned int); | |
1231 | ||
1232 | struct blk_integrity { | |
1233 | integrity_gen_fn *generate_fn; | |
1234 | integrity_vrfy_fn *verify_fn; | |
1235 | integrity_set_tag_fn *set_tag_fn; | |
1236 | integrity_get_tag_fn *get_tag_fn; | |
1237 | ||
1238 | unsigned short flags; | |
1239 | unsigned short tuple_size; | |
1240 | unsigned short sector_size; | |
1241 | unsigned short tag_size; | |
1242 | ||
1243 | const char *name; | |
1244 | ||
1245 | struct kobject kobj; | |
1246 | }; | |
1247 | ||
1248 | extern int blk_integrity_register(struct gendisk *, struct blk_integrity *); | |
1249 | extern void blk_integrity_unregister(struct gendisk *); | |
ad7fce93 | 1250 | extern int blk_integrity_compare(struct gendisk *, struct gendisk *); |
7ba1ba12 MP |
1251 | extern int blk_rq_map_integrity_sg(struct request *, struct scatterlist *); |
1252 | extern int blk_rq_count_integrity_sg(struct request *); | |
1253 | ||
b04accc4 JA |
1254 | static inline |
1255 | struct blk_integrity *bdev_get_integrity(struct block_device *bdev) | |
1256 | { | |
1257 | return bdev->bd_disk->integrity; | |
1258 | } | |
1259 | ||
b02739b0 MP |
1260 | static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) |
1261 | { | |
1262 | return disk->integrity; | |
1263 | } | |
1264 | ||
7ba1ba12 MP |
1265 | static inline int blk_integrity_rq(struct request *rq) |
1266 | { | |
d442cc44 MP |
1267 | if (rq->bio == NULL) |
1268 | return 0; | |
1269 | ||
7ba1ba12 MP |
1270 | return bio_integrity(rq->bio); |
1271 | } | |
1272 | ||
1273 | #else /* CONFIG_BLK_DEV_INTEGRITY */ | |
1274 | ||
1275 | #define blk_integrity_rq(rq) (0) | |
1276 | #define blk_rq_count_integrity_sg(a) (0) | |
1277 | #define blk_rq_map_integrity_sg(a, b) (0) | |
b04accc4 | 1278 | #define bdev_get_integrity(a) (0) |
b02739b0 | 1279 | #define blk_get_integrity(a) (0) |
7ba1ba12 MP |
1280 | #define blk_integrity_compare(a, b) (0) |
1281 | #define blk_integrity_register(a, b) (0) | |
1282 | #define blk_integrity_unregister(a) do { } while (0); | |
1283 | ||
1284 | #endif /* CONFIG_BLK_DEV_INTEGRITY */ | |
1285 | ||
08f85851 | 1286 | struct block_device_operations { |
d4430d62 AV |
1287 | int (*open) (struct block_device *, fmode_t); |
1288 | int (*release) (struct gendisk *, fmode_t); | |
1289 | int (*locked_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); | |
1290 | int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); | |
1291 | int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long); | |
08f85851 AV |
1292 | int (*direct_access) (struct block_device *, sector_t, |
1293 | void **, unsigned long *); | |
1294 | int (*media_changed) (struct gendisk *); | |
db429e9e BZ |
1295 | unsigned long long (*set_capacity) (struct gendisk *, |
1296 | unsigned long long); | |
08f85851 AV |
1297 | int (*revalidate_disk) (struct gendisk *); |
1298 | int (*getgeo)(struct block_device *, struct hd_geometry *); | |
1299 | struct module *owner; | |
1300 | }; | |
1301 | ||
633a08b8 AV |
1302 | extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int, |
1303 | unsigned long); | |
9361401e DH |
1304 | #else /* CONFIG_BLOCK */ |
1305 | /* | |
1306 | * stubs for when the block layer is configured out | |
1307 | */ | |
1308 | #define buffer_heads_over_limit 0 | |
1309 | ||
9361401e DH |
1310 | static inline long nr_blockdev_pages(void) |
1311 | { | |
1312 | return 0; | |
1313 | } | |
1314 | ||
9361401e DH |
1315 | #endif /* CONFIG_BLOCK */ |
1316 | ||
1da177e4 | 1317 | #endif |