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-rw-r--r--drivers/md/dm.h195
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
new file mode 100644
index 000000000000..e38c3fc1a1db
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1/*
2 * Internal header file for device mapper
3 *
4 * Copyright (C) 2001, 2002 Sistina Software
5 * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
6 *
7 * This file is released under the LGPL.
8 */
9
10#ifndef DM_INTERNAL_H
11#define DM_INTERNAL_H
12
13#include <linux/fs.h>
14#include <linux/device-mapper.h>
15#include <linux/list.h>
16#include <linux/blkdev.h>
17
18#define DM_NAME "device-mapper"
19#define DMWARN(f, x...) printk(KERN_WARNING DM_NAME ": " f "\n" , ## x)
20#define DMERR(f, x...) printk(KERN_ERR DM_NAME ": " f "\n" , ## x)
21#define DMINFO(f, x...) printk(KERN_INFO DM_NAME ": " f "\n" , ## x)
22
23#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
24 0 : scnprintf(result + sz, maxlen - sz, x))
25
26/*
27 * FIXME: I think this should be with the definition of sector_t
28 * in types.h.
29 */
30#ifdef CONFIG_LBD
31#define SECTOR_FORMAT "%Lu"
32#else
33#define SECTOR_FORMAT "%lu"
34#endif
35
36#define SECTOR_SHIFT 9
37
38/*
39 * List of devices that a metadevice uses and should open/close.
40 */
41struct dm_dev {
42 struct list_head list;
43
44 atomic_t count;
45 int mode;
46 struct block_device *bdev;
47 char name[16];
48};
49
50struct dm_table;
51struct mapped_device;
52
53/*-----------------------------------------------------------------
54 * Functions for manipulating a struct mapped_device.
55 * Drop the reference with dm_put when you finish with the object.
56 *---------------------------------------------------------------*/
57int dm_create(struct mapped_device **md);
58int dm_create_with_minor(unsigned int minor, struct mapped_device **md);
59void dm_set_mdptr(struct mapped_device *md, void *ptr);
60void *dm_get_mdptr(dev_t dev);
61
62/*
63 * Reference counting for md.
64 */
65void dm_get(struct mapped_device *md);
66void dm_put(struct mapped_device *md);
67
68/*
69 * A device can still be used while suspended, but I/O is deferred.
70 */
71int dm_suspend(struct mapped_device *md);
72int dm_resume(struct mapped_device *md);
73
74/*
75 * The device must be suspended before calling this method.
76 */
77int dm_swap_table(struct mapped_device *md, struct dm_table *t);
78
79/*
80 * Drop a reference on the table when you've finished with the
81 * result.
82 */
83struct dm_table *dm_get_table(struct mapped_device *md);
84
85/*
86 * Event functions.
87 */
88uint32_t dm_get_event_nr(struct mapped_device *md);
89int dm_wait_event(struct mapped_device *md, int event_nr);
90
91/*
92 * Info functions.
93 */
94struct gendisk *dm_disk(struct mapped_device *md);
95int dm_suspended(struct mapped_device *md);
96
97/*-----------------------------------------------------------------
98 * Functions for manipulating a table. Tables are also reference
99 * counted.
100 *---------------------------------------------------------------*/
101int dm_table_create(struct dm_table **result, int mode, unsigned num_targets);
102
103void dm_table_get(struct dm_table *t);
104void dm_table_put(struct dm_table *t);
105
106int dm_table_add_target(struct dm_table *t, const char *type,
107 sector_t start, sector_t len, char *params);
108int dm_table_complete(struct dm_table *t);
109void dm_table_event_callback(struct dm_table *t,
110 void (*fn)(void *), void *context);
111void dm_table_event(struct dm_table *t);
112sector_t dm_table_get_size(struct dm_table *t);
113struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
114struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
115void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q);
116unsigned int dm_table_get_num_targets(struct dm_table *t);
117struct list_head *dm_table_get_devices(struct dm_table *t);
118int dm_table_get_mode(struct dm_table *t);
119void dm_table_presuspend_targets(struct dm_table *t);
120void dm_table_postsuspend_targets(struct dm_table *t);
121void dm_table_resume_targets(struct dm_table *t);
122int dm_table_any_congested(struct dm_table *t, int bdi_bits);
123void dm_table_unplug_all(struct dm_table *t);
124int dm_table_flush_all(struct dm_table *t);
125
126/*-----------------------------------------------------------------
127 * A registry of target types.
128 *---------------------------------------------------------------*/
129int dm_target_init(void);
130void dm_target_exit(void);
131struct target_type *dm_get_target_type(const char *name);
132void dm_put_target_type(struct target_type *t);
133int dm_target_iterate(void (*iter_func)(struct target_type *tt,
134 void *param), void *param);
135
136
137/*-----------------------------------------------------------------
138 * Useful inlines.
139 *---------------------------------------------------------------*/
140static inline int array_too_big(unsigned long fixed, unsigned long obj,
141 unsigned long num)
142{
143 return (num > (ULONG_MAX - fixed) / obj);
144}
145
146/*
147 * Ceiling(n / sz)
148 */
149#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))
150
151#define dm_sector_div_up(n, sz) ( \
152{ \
153 sector_t _r = ((n) + (sz) - 1); \
154 sector_div(_r, (sz)); \
155 _r; \
156} \
157)
158
159/*
160 * ceiling(n / size) * size
161 */
162#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
163
164static inline sector_t to_sector(unsigned long n)
165{
166 return (n >> 9);
167}
168
169static inline unsigned long to_bytes(sector_t n)
170{
171 return (n << 9);
172}
173
174int dm_split_args(int *argc, char ***argvp, char *input);
175
176/*
177 * The device-mapper can be driven through one of two interfaces;
178 * ioctl or filesystem, depending which patch you have applied.
179 */
180int dm_interface_init(void);
181void dm_interface_exit(void);
182
183/*
184 * Targets for linear and striped mappings
185 */
186int dm_linear_init(void);
187void dm_linear_exit(void);
188
189int dm_stripe_init(void);
190void dm_stripe_exit(void);
191
192void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
193union map_info *dm_get_mapinfo(struct bio *bio);
194
195#endif