Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001 Sistina Software (UK) Limited. | |
0da336e5 | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
5 | * This file is released under the LGPL. | |
6 | */ | |
7 | ||
8 | #ifndef _LINUX_DEVICE_MAPPER_H | |
9 | #define _LINUX_DEVICE_MAPPER_H | |
10 | ||
416cd17b | 11 | #include <linux/bio.h> |
f6fccb12 | 12 | #include <linux/blkdev.h> |
71a16736 | 13 | #include <linux/ratelimit.h> |
416cd17b | 14 | |
af4874e0 | 15 | struct dm_dev; |
1da177e4 LT |
16 | struct dm_target; |
17 | struct dm_table; | |
17b2f66f | 18 | struct mapped_device; |
f6fccb12 | 19 | struct bio_vec; |
1da177e4 LT |
20 | |
21 | typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t; | |
22 | ||
23 | union map_info { | |
24 | void *ptr; | |
25 | unsigned long long ll; | |
26 | }; | |
27 | ||
28 | /* | |
29 | * In the constructor the target parameter will already have the | |
30 | * table, type, begin and len fields filled in. | |
31 | */ | |
32 | typedef int (*dm_ctr_fn) (struct dm_target *target, | |
33 | unsigned int argc, char **argv); | |
34 | ||
35 | /* | |
36 | * The destructor doesn't need to free the dm_target, just | |
37 | * anything hidden ti->private. | |
38 | */ | |
39 | typedef void (*dm_dtr_fn) (struct dm_target *ti); | |
40 | ||
41 | /* | |
42 | * The map function must return: | |
43 | * < 0: error | |
44 | * = 0: The target will handle the io by resubmitting it later | |
45cbcd79 | 45 | * = 1: simple remap complete |
2e93ccc1 | 46 | * = 2: The target wants to push back the io |
1da177e4 | 47 | */ |
7de3ee57 | 48 | typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio); |
7d76345d KU |
49 | typedef int (*dm_map_request_fn) (struct dm_target *ti, struct request *clone, |
50 | union map_info *map_context); | |
1da177e4 LT |
51 | |
52 | /* | |
53 | * Returns: | |
54 | * < 0 : error (currently ignored) | |
55 | * 0 : ended successfully | |
56 | * 1 : for some reason the io has still not completed (eg, | |
57 | * multipath target might want to requeue a failed io). | |
2e93ccc1 | 58 | * 2 : The target wants to push back the io |
1da177e4 LT |
59 | */ |
60 | typedef int (*dm_endio_fn) (struct dm_target *ti, | |
7de3ee57 | 61 | struct bio *bio, int error); |
7d76345d KU |
62 | typedef int (*dm_request_endio_fn) (struct dm_target *ti, |
63 | struct request *clone, int error, | |
64 | union map_info *map_context); | |
1da177e4 LT |
65 | |
66 | typedef void (*dm_presuspend_fn) (struct dm_target *ti); | |
67 | typedef void (*dm_postsuspend_fn) (struct dm_target *ti); | |
8757b776 | 68 | typedef int (*dm_preresume_fn) (struct dm_target *ti); |
1da177e4 LT |
69 | typedef void (*dm_resume_fn) (struct dm_target *ti); |
70 | ||
fd7c092e MP |
71 | typedef void (*dm_status_fn) (struct dm_target *ti, status_type_t status_type, |
72 | unsigned status_flags, char *result, unsigned maxlen); | |
1da177e4 LT |
73 | |
74 | typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv); | |
75 | ||
647b3d00 | 76 | typedef int (*dm_ioctl_fn) (struct dm_target *ti, unsigned int cmd, |
aa129a22 MB |
77 | unsigned long arg); |
78 | ||
f6fccb12 MB |
79 | typedef int (*dm_merge_fn) (struct dm_target *ti, struct bvec_merge_data *bvm, |
80 | struct bio_vec *biovec, int max_size); | |
81 | ||
af4874e0 MS |
82 | typedef int (*iterate_devices_callout_fn) (struct dm_target *ti, |
83 | struct dm_dev *dev, | |
5dea271b | 84 | sector_t start, sector_t len, |
af4874e0 MS |
85 | void *data); |
86 | ||
87 | typedef int (*dm_iterate_devices_fn) (struct dm_target *ti, | |
88 | iterate_devices_callout_fn fn, | |
89 | void *data); | |
90 | ||
40bea431 MS |
91 | typedef void (*dm_io_hints_fn) (struct dm_target *ti, |
92 | struct queue_limits *limits); | |
93 | ||
7d76345d KU |
94 | /* |
95 | * Returns: | |
96 | * 0: The target can handle the next I/O immediately. | |
97 | * 1: The target can't handle the next I/O immediately. | |
98 | */ | |
99 | typedef int (*dm_busy_fn) (struct dm_target *ti); | |
100 | ||
1da177e4 LT |
101 | void dm_error(const char *message); |
102 | ||
3cb40214 BR |
103 | /* |
104 | * Combine device limits. | |
105 | */ | |
754c5fc7 | 106 | int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev, |
5dea271b | 107 | sector_t start, sector_t len, void *data); |
3cb40214 | 108 | |
82b1519b MP |
109 | struct dm_dev { |
110 | struct block_device *bdev; | |
aeb5d727 | 111 | fmode_t mode; |
82b1519b MP |
112 | char name[16]; |
113 | }; | |
114 | ||
1da177e4 LT |
115 | /* |
116 | * Constructors should call these functions to ensure destination devices | |
117 | * are opened/closed correctly. | |
1da177e4 | 118 | */ |
8215d6ec NK |
119 | int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode, |
120 | struct dm_dev **result); | |
1da177e4 LT |
121 | void dm_put_device(struct dm_target *ti, struct dm_dev *d); |
122 | ||
123 | /* | |
124 | * Information about a target type | |
125 | */ | |
ab4c1424 | 126 | |
1da177e4 | 127 | struct target_type { |
ab4c1424 | 128 | uint64_t features; |
1da177e4 LT |
129 | const char *name; |
130 | struct module *module; | |
17b2f66f | 131 | unsigned version[3]; |
1da177e4 LT |
132 | dm_ctr_fn ctr; |
133 | dm_dtr_fn dtr; | |
134 | dm_map_fn map; | |
7d76345d | 135 | dm_map_request_fn map_rq; |
1da177e4 | 136 | dm_endio_fn end_io; |
7d76345d | 137 | dm_request_endio_fn rq_end_io; |
1da177e4 LT |
138 | dm_presuspend_fn presuspend; |
139 | dm_postsuspend_fn postsuspend; | |
8757b776 | 140 | dm_preresume_fn preresume; |
1da177e4 LT |
141 | dm_resume_fn resume; |
142 | dm_status_fn status; | |
143 | dm_message_fn message; | |
aa129a22 | 144 | dm_ioctl_fn ioctl; |
f6fccb12 | 145 | dm_merge_fn merge; |
7d76345d | 146 | dm_busy_fn busy; |
af4874e0 | 147 | dm_iterate_devices_fn iterate_devices; |
40bea431 | 148 | dm_io_hints_fn io_hints; |
45194e4f CR |
149 | |
150 | /* For internal device-mapper use. */ | |
151 | struct list_head list; | |
1da177e4 LT |
152 | }; |
153 | ||
3791e2fc AK |
154 | /* |
155 | * Target features | |
156 | */ | |
157 | ||
158 | /* | |
159 | * Any table that contains an instance of this target must have only one. | |
160 | */ | |
161 | #define DM_TARGET_SINGLETON 0x00000001 | |
162 | #define dm_target_needs_singleton(type) ((type)->features & DM_TARGET_SINGLETON) | |
163 | ||
cc6cbe14 AK |
164 | /* |
165 | * Indicates that a target does not support read-only devices. | |
166 | */ | |
167 | #define DM_TARGET_ALWAYS_WRITEABLE 0x00000002 | |
168 | #define dm_target_always_writeable(type) \ | |
169 | ((type)->features & DM_TARGET_ALWAYS_WRITEABLE) | |
170 | ||
36a0456f AK |
171 | /* |
172 | * Any device that contains a table with an instance of this target may never | |
173 | * have tables containing any different target type. | |
174 | */ | |
175 | #define DM_TARGET_IMMUTABLE 0x00000004 | |
176 | #define dm_target_is_immutable(type) ((type)->features & DM_TARGET_IMMUTABLE) | |
177 | ||
b0d8ed4d AK |
178 | /* |
179 | * Some targets need to be sent the same WRITE bio severals times so | |
180 | * that they can send copies of it to different devices. This function | |
181 | * examines any supplied bio and returns the number of copies of it the | |
182 | * target requires. | |
183 | */ | |
184 | typedef unsigned (*dm_num_write_bios_fn) (struct dm_target *ti, struct bio *bio); | |
185 | ||
1da177e4 LT |
186 | struct dm_target { |
187 | struct dm_table *table; | |
188 | struct target_type *type; | |
189 | ||
190 | /* target limits */ | |
191 | sector_t begin; | |
192 | sector_t len; | |
193 | ||
542f9038 MS |
194 | /* If non-zero, maximum size of I/O submitted to a target. */ |
195 | uint32_t max_io_len; | |
1da177e4 | 196 | |
f9ab94ce | 197 | /* |
55a62eef | 198 | * A number of zero-length barrier bios that will be submitted |
f9ab94ce MP |
199 | * to the target for the purpose of flushing cache. |
200 | * | |
55a62eef AK |
201 | * The bio number can be accessed with dm_bio_get_target_bio_nr. |
202 | * It is a responsibility of the target driver to remap these bios | |
f9ab94ce MP |
203 | * to the real underlying devices. |
204 | */ | |
55a62eef | 205 | unsigned num_flush_bios; |
f9ab94ce | 206 | |
5ae89a87 | 207 | /* |
55a62eef AK |
208 | * The number of discard bios that will be submitted to the target. |
209 | * The bio number can be accessed with dm_bio_get_target_bio_nr. | |
5ae89a87 | 210 | */ |
55a62eef | 211 | unsigned num_discard_bios; |
5ae89a87 | 212 | |
d54eaa5a | 213 | /* |
55a62eef AK |
214 | * The number of WRITE SAME bios that will be submitted to the target. |
215 | * The bio number can be accessed with dm_bio_get_target_bio_nr. | |
d54eaa5a | 216 | */ |
55a62eef | 217 | unsigned num_write_same_bios; |
d54eaa5a | 218 | |
c0820cf5 MP |
219 | /* |
220 | * The minimum number of extra bytes allocated in each bio for the | |
221 | * target to use. dm_per_bio_data returns the data location. | |
222 | */ | |
223 | unsigned per_bio_data_size; | |
224 | ||
b0d8ed4d AK |
225 | /* |
226 | * If defined, this function is called to find out how many | |
227 | * duplicate bios should be sent to the target when writing | |
228 | * data. | |
229 | */ | |
230 | dm_num_write_bios_fn num_write_bios; | |
231 | ||
1da177e4 LT |
232 | /* target specific data */ |
233 | void *private; | |
234 | ||
235 | /* Used to provide an error string from the ctr */ | |
236 | char *error; | |
4c259327 | 237 | |
0e9c24ed JT |
238 | /* |
239 | * Set if this target needs to receive flushes regardless of | |
240 | * whether or not its underlying devices have support. | |
241 | */ | |
242 | bool flush_supported:1; | |
243 | ||
4c259327 MS |
244 | /* |
245 | * Set if this target needs to receive discards regardless of | |
246 | * whether or not its underlying devices have support. | |
247 | */ | |
0ac55489 | 248 | bool discards_supported:1; |
983c7db3 | 249 | |
7acf0277 | 250 | /* |
55a62eef | 251 | * Set if the target required discard bios to be split |
7acf0277 MP |
252 | * on max_io_len boundary. |
253 | */ | |
55a62eef | 254 | bool split_discard_bios:1; |
7acf0277 | 255 | |
983c7db3 MB |
256 | /* |
257 | * Set if this target does not return zeroes on discarded blocks. | |
258 | */ | |
0ac55489 | 259 | bool discard_zeroes_data_unsupported:1; |
1da177e4 LT |
260 | }; |
261 | ||
9d357b07 N |
262 | /* Each target can link one of these into the table */ |
263 | struct dm_target_callbacks { | |
264 | struct list_head list; | |
265 | int (*congested_fn) (struct dm_target_callbacks *, int); | |
266 | }; | |
267 | ||
c0820cf5 MP |
268 | /* |
269 | * For bio-based dm. | |
270 | * One of these is allocated for each bio. | |
271 | * This structure shouldn't be touched directly by target drivers. | |
272 | * It is here so that we can inline dm_per_bio_data and | |
273 | * dm_bio_from_per_bio_data | |
274 | */ | |
275 | struct dm_target_io { | |
276 | struct dm_io *io; | |
277 | struct dm_target *ti; | |
278 | union map_info info; | |
55a62eef | 279 | unsigned target_bio_nr; |
c0820cf5 MP |
280 | struct bio clone; |
281 | }; | |
282 | ||
283 | static inline void *dm_per_bio_data(struct bio *bio, size_t data_size) | |
284 | { | |
285 | return (char *)bio - offsetof(struct dm_target_io, clone) - data_size; | |
286 | } | |
287 | ||
288 | static inline struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size) | |
289 | { | |
290 | return (struct bio *)((char *)data + data_size + offsetof(struct dm_target_io, clone)); | |
291 | } | |
292 | ||
55a62eef | 293 | static inline unsigned dm_bio_get_target_bio_nr(const struct bio *bio) |
ddbd658f | 294 | { |
55a62eef | 295 | return container_of(bio, struct dm_target_io, clone)->target_bio_nr; |
ddbd658f MP |
296 | } |
297 | ||
1da177e4 | 298 | int dm_register_target(struct target_type *t); |
10d3bd09 | 299 | void dm_unregister_target(struct target_type *t); |
17b2f66f | 300 | |
498f0103 MS |
301 | /* |
302 | * Target argument parsing. | |
303 | */ | |
304 | struct dm_arg_set { | |
305 | unsigned argc; | |
306 | char **argv; | |
307 | }; | |
308 | ||
309 | /* | |
310 | * The minimum and maximum value of a numeric argument, together with | |
311 | * the error message to use if the number is found to be outside that range. | |
312 | */ | |
313 | struct dm_arg { | |
314 | unsigned min; | |
315 | unsigned max; | |
316 | char *error; | |
317 | }; | |
318 | ||
319 | /* | |
320 | * Validate the next argument, either returning it as *value or, if invalid, | |
321 | * returning -EINVAL and setting *error. | |
322 | */ | |
323 | int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set, | |
324 | unsigned *value, char **error); | |
325 | ||
326 | /* | |
327 | * Process the next argument as the start of a group containing between | |
328 | * arg->min and arg->max further arguments. Either return the size as | |
329 | * *num_args or, if invalid, return -EINVAL and set *error. | |
330 | */ | |
331 | int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set, | |
332 | unsigned *num_args, char **error); | |
333 | ||
334 | /* | |
335 | * Return the current argument and shift to the next. | |
336 | */ | |
337 | const char *dm_shift_arg(struct dm_arg_set *as); | |
338 | ||
339 | /* | |
340 | * Move through num_args arguments. | |
341 | */ | |
342 | void dm_consume_args(struct dm_arg_set *as, unsigned num_args); | |
343 | ||
17b2f66f AK |
344 | /*----------------------------------------------------------------- |
345 | * Functions for creating and manipulating mapped devices. | |
346 | * Drop the reference with dm_put when you finish with the object. | |
347 | *---------------------------------------------------------------*/ | |
348 | ||
349 | /* | |
350 | * DM_ANY_MINOR chooses the next available minor number. | |
351 | */ | |
352 | #define DM_ANY_MINOR (-1) | |
353 | int dm_create(int minor, struct mapped_device **md); | |
354 | ||
355 | /* | |
356 | * Reference counting for md. | |
357 | */ | |
358 | struct mapped_device *dm_get_md(dev_t dev); | |
359 | void dm_get(struct mapped_device *md); | |
360 | void dm_put(struct mapped_device *md); | |
361 | ||
362 | /* | |
363 | * An arbitrary pointer may be stored alongside a mapped device. | |
364 | */ | |
365 | void dm_set_mdptr(struct mapped_device *md, void *ptr); | |
366 | void *dm_get_mdptr(struct mapped_device *md); | |
367 | ||
368 | /* | |
369 | * A device can still be used while suspended, but I/O is deferred. | |
370 | */ | |
a3d77d35 | 371 | int dm_suspend(struct mapped_device *md, unsigned suspend_flags); |
17b2f66f AK |
372 | int dm_resume(struct mapped_device *md); |
373 | ||
374 | /* | |
375 | * Event functions. | |
376 | */ | |
377 | uint32_t dm_get_event_nr(struct mapped_device *md); | |
378 | int dm_wait_event(struct mapped_device *md, int event_nr); | |
7a8c3d3b MA |
379 | uint32_t dm_next_uevent_seq(struct mapped_device *md); |
380 | void dm_uevent_add(struct mapped_device *md, struct list_head *elist); | |
17b2f66f AK |
381 | |
382 | /* | |
383 | * Info functions. | |
384 | */ | |
72d94861 | 385 | const char *dm_device_name(struct mapped_device *md); |
96a1f7db | 386 | int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid); |
17b2f66f | 387 | struct gendisk *dm_disk(struct mapped_device *md); |
64dbce58 | 388 | int dm_suspended(struct dm_target *ti); |
2e93ccc1 | 389 | int dm_noflush_suspending(struct dm_target *ti); |
89343da0 | 390 | union map_info *dm_get_mapinfo(struct bio *bio); |
cec47e3d | 391 | union map_info *dm_get_rq_mapinfo(struct request *rq); |
17b2f66f AK |
392 | |
393 | /* | |
394 | * Geometry functions. | |
395 | */ | |
396 | int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo); | |
397 | int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo); | |
398 | ||
399 | ||
400 | /*----------------------------------------------------------------- | |
401 | * Functions for manipulating device-mapper tables. | |
402 | *---------------------------------------------------------------*/ | |
403 | ||
404 | /* | |
405 | * First create an empty table. | |
406 | */ | |
aeb5d727 | 407 | int dm_table_create(struct dm_table **result, fmode_t mode, |
17b2f66f AK |
408 | unsigned num_targets, struct mapped_device *md); |
409 | ||
410 | /* | |
411 | * Then call this once for each target. | |
412 | */ | |
413 | int dm_table_add_target(struct dm_table *t, const char *type, | |
414 | sector_t start, sector_t len, char *params); | |
415 | ||
9d357b07 N |
416 | /* |
417 | * Target_ctr should call this if it needs to add any callbacks. | |
418 | */ | |
419 | void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb); | |
420 | ||
17b2f66f AK |
421 | /* |
422 | * Finally call this to make the table ready for use. | |
423 | */ | |
424 | int dm_table_complete(struct dm_table *t); | |
425 | ||
542f9038 MS |
426 | /* |
427 | * Target may require that it is never sent I/O larger than len. | |
428 | */ | |
429 | int __must_check dm_set_target_max_io_len(struct dm_target *ti, sector_t len); | |
430 | ||
17b2f66f AK |
431 | /* |
432 | * Table reference counting. | |
433 | */ | |
7c666411 | 434 | struct dm_table *dm_get_live_table(struct mapped_device *md); |
17b2f66f AK |
435 | void dm_table_get(struct dm_table *t); |
436 | void dm_table_put(struct dm_table *t); | |
437 | ||
438 | /* | |
439 | * Queries | |
440 | */ | |
441 | sector_t dm_table_get_size(struct dm_table *t); | |
442 | unsigned int dm_table_get_num_targets(struct dm_table *t); | |
aeb5d727 | 443 | fmode_t dm_table_get_mode(struct dm_table *t); |
17b2f66f AK |
444 | struct mapped_device *dm_table_get_md(struct dm_table *t); |
445 | ||
446 | /* | |
447 | * Trigger an event. | |
448 | */ | |
449 | void dm_table_event(struct dm_table *t); | |
450 | ||
451 | /* | |
452 | * The device must be suspended before calling this method. | |
042d2a9b | 453 | * Returns the previous table, which the caller must destroy. |
17b2f66f | 454 | */ |
042d2a9b AK |
455 | struct dm_table *dm_swap_table(struct mapped_device *md, |
456 | struct dm_table *t); | |
17b2f66f | 457 | |
54160904 MP |
458 | /* |
459 | * A wrapper around vmalloc. | |
460 | */ | |
461 | void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size); | |
462 | ||
0da336e5 AK |
463 | /*----------------------------------------------------------------- |
464 | * Macros. | |
465 | *---------------------------------------------------------------*/ | |
466 | #define DM_NAME "device-mapper" | |
467 | ||
71a16736 NK |
468 | #ifdef CONFIG_PRINTK |
469 | extern struct ratelimit_state dm_ratelimit_state; | |
470 | ||
471 | #define dm_ratelimit() __ratelimit(&dm_ratelimit_state) | |
472 | #else | |
473 | #define dm_ratelimit() 0 | |
474 | #endif | |
475 | ||
10d3bd09 MP |
476 | #define DMCRIT(f, arg...) \ |
477 | printk(KERN_CRIT DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) | |
478 | ||
0da336e5 AK |
479 | #define DMERR(f, arg...) \ |
480 | printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) | |
481 | #define DMERR_LIMIT(f, arg...) \ | |
482 | do { \ | |
71a16736 | 483 | if (dm_ratelimit()) \ |
0da336e5 AK |
484 | printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " \ |
485 | f "\n", ## arg); \ | |
486 | } while (0) | |
487 | ||
488 | #define DMWARN(f, arg...) \ | |
489 | printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) | |
490 | #define DMWARN_LIMIT(f, arg...) \ | |
491 | do { \ | |
71a16736 | 492 | if (dm_ratelimit()) \ |
0da336e5 AK |
493 | printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " \ |
494 | f "\n", ## arg); \ | |
495 | } while (0) | |
496 | ||
497 | #define DMINFO(f, arg...) \ | |
498 | printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg) | |
499 | #define DMINFO_LIMIT(f, arg...) \ | |
500 | do { \ | |
71a16736 | 501 | if (dm_ratelimit()) \ |
0da336e5 AK |
502 | printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f \ |
503 | "\n", ## arg); \ | |
504 | } while (0) | |
505 | ||
506 | #ifdef CONFIG_DM_DEBUG | |
507 | # define DMDEBUG(f, arg...) \ | |
508 | printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg) | |
509 | # define DMDEBUG_LIMIT(f, arg...) \ | |
510 | do { \ | |
71a16736 | 511 | if (dm_ratelimit()) \ |
0da336e5 AK |
512 | printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX ": " f \ |
513 | "\n", ## arg); \ | |
514 | } while (0) | |
515 | #else | |
516 | # define DMDEBUG(f, arg...) do {} while (0) | |
517 | # define DMDEBUG_LIMIT(f, arg...) do {} while (0) | |
518 | #endif | |
519 | ||
520 | #define DMEMIT(x...) sz += ((sz >= maxlen) ? \ | |
521 | 0 : scnprintf(result + sz, maxlen - sz, x)) | |
522 | ||
523 | #define SECTOR_SHIFT 9 | |
524 | ||
525 | /* | |
526 | * Definitions of return values from target end_io function. | |
527 | */ | |
528 | #define DM_ENDIO_INCOMPLETE 1 | |
529 | #define DM_ENDIO_REQUEUE 2 | |
530 | ||
531 | /* | |
532 | * Definitions of return values from target map function. | |
533 | */ | |
534 | #define DM_MAPIO_SUBMITTED 0 | |
535 | #define DM_MAPIO_REMAPPED 1 | |
536 | #define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE | |
537 | ||
538 | /* | |
539 | * Ceiling(n / sz) | |
540 | */ | |
541 | #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) | |
542 | ||
543 | #define dm_sector_div_up(n, sz) ( \ | |
544 | { \ | |
545 | sector_t _r = ((n) + (sz) - 1); \ | |
546 | sector_div(_r, (sz)); \ | |
547 | _r; \ | |
548 | } \ | |
549 | ) | |
550 | ||
551 | /* | |
552 | * ceiling(n / size) * size | |
553 | */ | |
554 | #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) | |
555 | ||
d63a5ce3 MP |
556 | #define dm_array_too_big(fixed, obj, num) \ |
557 | ((num) > (UINT_MAX - (fixed)) / (obj)) | |
558 | ||
56a67df7 MS |
559 | /* |
560 | * Sector offset taken relative to the start of the target instead of | |
561 | * relative to the start of the device. | |
562 | */ | |
563 | #define dm_target_offset(ti, sector) ((sector) - (ti)->begin) | |
564 | ||
0da336e5 AK |
565 | static inline sector_t to_sector(unsigned long n) |
566 | { | |
567 | return (n >> SECTOR_SHIFT); | |
568 | } | |
569 | ||
570 | static inline unsigned long to_bytes(sector_t n) | |
571 | { | |
572 | return (n << SECTOR_SHIFT); | |
573 | } | |
574 | ||
cec47e3d KU |
575 | /*----------------------------------------------------------------- |
576 | * Helper for block layer and dm core operations | |
577 | *---------------------------------------------------------------*/ | |
578 | void dm_dispatch_request(struct request *rq); | |
579 | void dm_requeue_unmapped_request(struct request *rq); | |
580 | void dm_kill_unmapped_request(struct request *rq, int error); | |
581 | int dm_underlying_device_busy(struct request_queue *q); | |
582 | ||
17b2f66f | 583 | #endif /* _LINUX_DEVICE_MAPPER_H */ |