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) 2004-2006 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#include <linux/hdreg.h>
18
19#define DM_NAME "device-mapper"
20
21#define DMERR(f, arg...) \
22 printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
23#define DMERR_LIMIT(f, arg...) \
24 do { \
25 if (printk_ratelimit()) \
26 printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " \
27 f "\n", ## arg); \
28 } while (0)
29
30#define DMWARN(f, arg...) \
31 printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
32#define DMWARN_LIMIT(f, arg...) \
33 do { \
34 if (printk_ratelimit()) \
35 printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " \
36 f "\n", ## arg); \
37 } while (0)
38
39#define DMINFO(f, arg...) \
40 printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
41#define DMINFO_LIMIT(f, arg...) \
42 do { \
43 if (printk_ratelimit()) \
44 printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f \
45 "\n", ## arg); \
46 } while (0)
47
48#ifdef CONFIG_DM_DEBUG
49# define DMDEBUG(f, arg...) \
50 printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg)
51# define DMDEBUG_LIMIT(f, arg...) \
52 do { \
53 if (printk_ratelimit()) \
54 printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX ": " f \
55 "\n", ## arg); \
56 } while (0)
57#else
58# define DMDEBUG(f, arg...) do {} while (0)
59# define DMDEBUG_LIMIT(f, arg...) do {} while (0)
60#endif
61
62#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
63 0 : scnprintf(result + sz, maxlen - sz, x))
64
65#define SECTOR_SHIFT 9
66
67/*
68 * Definitions of return values from target end_io function.
69 */
70#define DM_ENDIO_INCOMPLETE 1
71#define DM_ENDIO_REQUEUE 2
72
73/*
74 * Definitions of return values from target map function.
75 */
76#define DM_MAPIO_SUBMITTED 0
77#define DM_MAPIO_REMAPPED 1
78#define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE
79
80/*
81 * Suspend feature flags
82 */
83#define DM_SUSPEND_LOCKFS_FLAG (1 << 0)
84#define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
85
86/*
87 * List of devices that a metadevice uses and should open/close.
88 */
89struct dm_dev {
90 struct list_head list;
91
92 atomic_t count;
93 int mode;
94 struct block_device *bdev;
95 char name[16];
96};
97
98struct dm_table;
99
100/*-----------------------------------------------------------------
101 * Internal table functions.
102 *---------------------------------------------------------------*/
103void dm_table_event_callback(struct dm_table *t,
104 void (*fn)(void *), void *context);
105struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
106struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
107void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q);
108struct list_head *dm_table_get_devices(struct dm_table *t);
109void dm_table_presuspend_targets(struct dm_table *t);
110void dm_table_postsuspend_targets(struct dm_table *t);
111int dm_table_resume_targets(struct dm_table *t);
112int dm_table_any_congested(struct dm_table *t, int bdi_bits);
113void dm_table_unplug_all(struct dm_table *t);
114
115/*
116 * To check the return value from dm_table_find_target().
117 */
118#define dm_target_is_valid(t) ((t)->table)
119
120/*-----------------------------------------------------------------
121 * A registry of target types.
122 *---------------------------------------------------------------*/
123int dm_target_init(void);
124void dm_target_exit(void);
125struct target_type *dm_get_target_type(const char *name);
126void dm_put_target_type(struct target_type *t);
127int dm_target_iterate(void (*iter_func)(struct target_type *tt,
128 void *param), void *param);
129
130/*-----------------------------------------------------------------
131 * Useful inlines.
132 *---------------------------------------------------------------*/
133static inline int array_too_big(unsigned long fixed, unsigned long obj,
134 unsigned long num)
135{
136 return (num > (ULONG_MAX - fixed) / obj);
137}
138
139/*
140 * Ceiling(n / sz)
141 */
142#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))
143
144#define dm_sector_div_up(n, sz) ( \
145{ \
146 sector_t _r = ((n) + (sz) - 1); \
147 sector_div(_r, (sz)); \
148 _r; \
149} \
150)
151
152/*
153 * ceiling(n / size) * size
154 */
155#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
156
157static inline sector_t to_sector(unsigned long n)
158{
159 return (n >> 9);
160}
161
162static inline unsigned long to_bytes(sector_t n)
163{
164 return (n << 9);
165}
166
167int dm_split_args(int *argc, char ***argvp, char *input);
168
169/*
170 * The device-mapper can be driven through one of two interfaces;
171 * ioctl or filesystem, depending which patch you have applied.
172 */
173int dm_interface_init(void);
174void dm_interface_exit(void);
175
176/*
177 * Targets for linear and striped mappings
178 */
179int dm_linear_init(void);
180void dm_linear_exit(void);
181
182int dm_stripe_init(void);
183void dm_stripe_exit(void);
184
185void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
186union map_info *dm_get_mapinfo(struct bio *bio);
187int dm_open_count(struct mapped_device *md);
188int dm_lock_for_deletion(struct mapped_device *md);
189
190void dm_kobject_uevent(struct mapped_device *md);
191
192#endif