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8#ifndef _LINUX_DEVICE_MAPPER_H
9#define _LINUX_DEVICE_MAPPER_H
10
11#include <linux/bio.h>
12#include <linux/blkdev.h>
13
14struct dm_dev;
15struct dm_target;
16struct dm_table;
17struct mapped_device;
18struct bio_vec;
19
20typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
21
22union map_info {
23 void *ptr;
24 unsigned long long ll;
25 unsigned target_request_nr;
26};
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31
32typedef int (*dm_ctr_fn) (struct dm_target *target,
33 unsigned int argc, char **argv);
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39typedef void (*dm_dtr_fn) (struct dm_target *ti);
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48typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio,
49 union map_info *map_context);
50typedef int (*dm_map_request_fn) (struct dm_target *ti, struct request *clone,
51 union map_info *map_context);
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60
61typedef int (*dm_endio_fn) (struct dm_target *ti,
62 struct bio *bio, int error,
63 union map_info *map_context);
64typedef int (*dm_request_endio_fn) (struct dm_target *ti,
65 struct request *clone, int error,
66 union map_info *map_context);
67
68typedef void (*dm_flush_fn) (struct dm_target *ti);
69typedef void (*dm_presuspend_fn) (struct dm_target *ti);
70typedef void (*dm_postsuspend_fn) (struct dm_target *ti);
71typedef int (*dm_preresume_fn) (struct dm_target *ti);
72typedef void (*dm_resume_fn) (struct dm_target *ti);
73
74typedef int (*dm_status_fn) (struct dm_target *ti, status_type_t status_type,
75 char *result, unsigned int maxlen);
76
77typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv);
78
79typedef int (*dm_ioctl_fn) (struct dm_target *ti, unsigned int cmd,
80 unsigned long arg);
81
82typedef int (*dm_merge_fn) (struct dm_target *ti, struct bvec_merge_data *bvm,
83 struct bio_vec *biovec, int max_size);
84
85typedef int (*iterate_devices_callout_fn) (struct dm_target *ti,
86 struct dm_dev *dev,
87 sector_t start, sector_t len,
88 void *data);
89
90typedef int (*dm_iterate_devices_fn) (struct dm_target *ti,
91 iterate_devices_callout_fn fn,
92 void *data);
93
94typedef void (*dm_io_hints_fn) (struct dm_target *ti,
95 struct queue_limits *limits);
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102typedef int (*dm_busy_fn) (struct dm_target *ti);
103
104void dm_error(const char *message);
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108
109int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
110 sector_t start, sector_t len, void *data);
111
112struct dm_dev {
113 struct block_device *bdev;
114 fmode_t mode;
115 char name[16];
116};
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121
122int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
123 struct dm_dev **result);
124void dm_put_device(struct dm_target *ti, struct dm_dev *d);
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133
134struct target_type {
135 uint64_t features;
136 const char *name;
137 struct module *module;
138 unsigned version[3];
139 dm_ctr_fn ctr;
140 dm_dtr_fn dtr;
141 dm_map_fn map;
142 dm_map_request_fn map_rq;
143 dm_endio_fn end_io;
144 dm_request_endio_fn rq_end_io;
145 dm_flush_fn flush;
146 dm_presuspend_fn presuspend;
147 dm_postsuspend_fn postsuspend;
148 dm_preresume_fn preresume;
149 dm_resume_fn resume;
150 dm_status_fn status;
151 dm_message_fn message;
152 dm_ioctl_fn ioctl;
153 dm_merge_fn merge;
154 dm_busy_fn busy;
155 dm_iterate_devices_fn iterate_devices;
156 dm_io_hints_fn io_hints;
157
158
159 struct list_head list;
160};
161
162struct dm_target {
163 struct dm_table *table;
164 struct target_type *type;
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166
167 sector_t begin;
168 sector_t len;
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171 sector_t split_io;
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181 unsigned num_flush_requests;
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187 unsigned num_discard_requests;
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190 void *private;
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193 char *error;
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199 unsigned discards_supported:1;
200};
201
202
203struct dm_target_callbacks {
204 struct list_head list;
205 int (*congested_fn) (struct dm_target_callbacks *, int);
206};
207
208int dm_register_target(struct target_type *t);
209void dm_unregister_target(struct target_type *t);
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218
219#define DM_ANY_MINOR (-1)
220int dm_create(int minor, struct mapped_device **md);
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225struct mapped_device *dm_get_md(dev_t dev);
226void dm_get(struct mapped_device *md);
227void dm_put(struct mapped_device *md);
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232void dm_set_mdptr(struct mapped_device *md, void *ptr);
233void *dm_get_mdptr(struct mapped_device *md);
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238int dm_suspend(struct mapped_device *md, unsigned suspend_flags);
239int dm_resume(struct mapped_device *md);
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244uint32_t dm_get_event_nr(struct mapped_device *md);
245int dm_wait_event(struct mapped_device *md, int event_nr);
246uint32_t dm_next_uevent_seq(struct mapped_device *md);
247void dm_uevent_add(struct mapped_device *md, struct list_head *elist);
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252const char *dm_device_name(struct mapped_device *md);
253int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid);
254struct gendisk *dm_disk(struct mapped_device *md);
255int dm_suspended(struct dm_target *ti);
256int dm_noflush_suspending(struct dm_target *ti);
257union map_info *dm_get_mapinfo(struct bio *bio);
258union map_info *dm_get_rq_mapinfo(struct request *rq);
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263int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo);
264int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo);
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274int dm_table_create(struct dm_table **result, fmode_t mode,
275 unsigned num_targets, struct mapped_device *md);
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280int dm_table_add_target(struct dm_table *t, const char *type,
281 sector_t start, sector_t len, char *params);
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286void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb);
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291int dm_table_complete(struct dm_table *t);
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296struct dm_table *dm_get_live_table(struct mapped_device *md);
297void dm_table_get(struct dm_table *t);
298void dm_table_put(struct dm_table *t);
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303sector_t dm_table_get_size(struct dm_table *t);
304unsigned int dm_table_get_num_targets(struct dm_table *t);
305fmode_t dm_table_get_mode(struct dm_table *t);
306struct mapped_device *dm_table_get_md(struct dm_table *t);
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311void dm_table_event(struct dm_table *t);
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317struct dm_table *dm_swap_table(struct mapped_device *md,
318 struct dm_table *t);
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322
323void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
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327
328#define DM_NAME "device-mapper"
329
330#define DMCRIT(f, arg...) \
331 printk(KERN_CRIT DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
332
333#define DMERR(f, arg...) \
334 printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
335#define DMERR_LIMIT(f, arg...) \
336 do { \
337 if (printk_ratelimit()) \
338 printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " \
339 f "\n", ## arg); \
340 } while (0)
341
342#define DMWARN(f, arg...) \
343 printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
344#define DMWARN_LIMIT(f, arg...) \
345 do { \
346 if (printk_ratelimit()) \
347 printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " \
348 f "\n", ## arg); \
349 } while (0)
350
351#define DMINFO(f, arg...) \
352 printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
353#define DMINFO_LIMIT(f, arg...) \
354 do { \
355 if (printk_ratelimit()) \
356 printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f \
357 "\n", ## arg); \
358 } while (0)
359
360#ifdef CONFIG_DM_DEBUG
361# define DMDEBUG(f, arg...) \
362 printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg)
363# define DMDEBUG_LIMIT(f, arg...) \
364 do { \
365 if (printk_ratelimit()) \
366 printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX ": " f \
367 "\n", ## arg); \
368 } while (0)
369#else
370# define DMDEBUG(f, arg...) do {} while (0)
371# define DMDEBUG_LIMIT(f, arg...) do {} while (0)
372#endif
373
374#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
375 0 : scnprintf(result + sz, maxlen - sz, x))
376
377#define SECTOR_SHIFT 9
378
379
380
381
382#define DM_ENDIO_INCOMPLETE 1
383#define DM_ENDIO_REQUEUE 2
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387
388#define DM_MAPIO_SUBMITTED 0
389#define DM_MAPIO_REMAPPED 1
390#define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE
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394
395#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))
396
397#define dm_sector_div_up(n, sz) ( \
398{ \
399 sector_t _r = ((n) + (sz) - 1); \
400 sector_div(_r, (sz)); \
401 _r; \
402} \
403)
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407
408#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
409
410#define dm_array_too_big(fixed, obj, num) \
411 ((num) > (UINT_MAX - (fixed)) / (obj))
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415
416
417#define dm_target_offset(ti, sector) ((sector) - (ti)->begin)
418
419static inline sector_t to_sector(unsigned long n)
420{
421 return (n >> SECTOR_SHIFT);
422}
423
424static inline unsigned long to_bytes(sector_t n)
425{
426 return (n << SECTOR_SHIFT);
427}
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430
431
432void dm_dispatch_request(struct request *rq);
433void dm_requeue_unmapped_request(struct request *rq);
434void dm_kill_unmapped_request(struct request *rq, int error);
435int dm_underlying_device_busy(struct request_queue *q);
436
437#endif
438