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