tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 "%llu"
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);
61struct mapped_device *dm_get_md(dev_t dev);
62
63/*
64 * Reference counting for md.
65 */
66void dm_get(struct mapped_device *md);
67void dm_put(struct mapped_device *md);
68
69/*
70 * A device can still be used while suspended, but I/O is deferred.
71 */
72int dm_suspend(struct mapped_device *md, int with_lockfs);
73int dm_resume(struct mapped_device *md);
74
75/*
76 * The device must be suspended before calling this method.
77 */
78int dm_swap_table(struct mapped_device *md, struct dm_table *t);
79
80/*
81 * Drop a reference on the table when you've finished with the
82 * result.
83 */
84struct dm_table *dm_get_table(struct mapped_device *md);
85
86/*
87 * Event functions.
88 */
89uint32_t dm_get_event_nr(struct mapped_device *md);
90int dm_wait_event(struct mapped_device *md, int event_nr);
91
92/*
93 * Info functions.
94 */
95struct gendisk *dm_disk(struct mapped_device *md);
96int dm_suspended(struct mapped_device *md);
97
98/*-----------------------------------------------------------------
99 * Functions for manipulating a table. Tables are also reference
100 * counted.
101 *---------------------------------------------------------------*/
102int dm_table_create(struct dm_table **result, int mode, unsigned num_targets);
103
104void dm_table_get(struct dm_table *t);
105void dm_table_put(struct dm_table *t);
106
107int dm_table_add_target(struct dm_table *t, const char *type,
108 sector_t start, sector_t len, char *params);
109int dm_table_complete(struct dm_table *t);
110void dm_table_event_callback(struct dm_table *t,
111 void (*fn)(void *), void *context);
112void dm_table_event(struct dm_table *t);
113sector_t dm_table_get_size(struct dm_table *t);
114struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
115struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
116void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q);
117unsigned int dm_table_get_num_targets(struct dm_table *t);
118struct list_head *dm_table_get_devices(struct dm_table *t);
119int dm_table_get_mode(struct dm_table *t);
120void dm_table_presuspend_targets(struct dm_table *t);
121void dm_table_postsuspend_targets(struct dm_table *t);
122void dm_table_resume_targets(struct dm_table *t);
123int dm_table_any_congested(struct dm_table *t, int bdi_bits);
124void dm_table_unplug_all(struct dm_table *t);
125int dm_table_flush_all(struct dm_table *t);
126
127/*-----------------------------------------------------------------
128 * A registry of target types.
129 *---------------------------------------------------------------*/
130int dm_target_init(void);
131void dm_target_exit(void);
132struct target_type *dm_get_target_type(const char *name);
133void dm_put_target_type(struct target_type *t);
134int dm_target_iterate(void (*iter_func)(struct target_type *tt,
135 void *param), void *param);
136
137
138/*-----------------------------------------------------------------
139 * Useful inlines.
140 *---------------------------------------------------------------*/
141static inline int array_too_big(unsigned long fixed, unsigned long obj,
142 unsigned long num)
143{
144 return (num > (ULONG_MAX - fixed) / obj);
145}
146
147/*
148 * Ceiling(n / sz)
149 */
150#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))
151
152#define dm_sector_div_up(n, sz) ( \
153{ \
154 sector_t _r = ((n) + (sz) - 1); \
155 sector_div(_r, (sz)); \
156 _r; \
157} \
158)
159
160/*
161 * ceiling(n / size) * size
162 */
163#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
164
165static inline sector_t to_sector(unsigned long n)
166{
167 return (n >> 9);
168}
169
170static inline unsigned long to_bytes(sector_t n)
171{
172 return (n << 9);
173}
174
175int dm_split_args(int *argc, char ***argvp, char *input);
176
177/*
178 * The device-mapper can be driven through one of two interfaces;
179 * ioctl or filesystem, depending which patch you have applied.
180 */
181int dm_interface_init(void);
182void dm_interface_exit(void);
183
184/*
185 * Targets for linear and striped mappings
186 */
187int dm_linear_init(void);
188void dm_linear_exit(void);
189
190int dm_stripe_init(void);
191void dm_stripe_exit(void);
192
193void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
194union map_info *dm_get_mapinfo(struct bio *bio);
195
196#endif