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 #include <linux/completion.h>
19 #include <linux/kobject.h>
20
21 /*
22 * Suspend feature flags
23 */
24 #define DM_SUSPEND_LOCKFS_FLAG (1 << 0)
25 #define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
26
27 /*
28 * Type of table and mapped_device's mempool
29 */
30 #define DM_TYPE_NONE 0
31 #define DM_TYPE_BIO_BASED 1
32 #define DM_TYPE_REQUEST_BASED 2
33
34 /*
35 * List of devices that a metadevice uses and should open/close.
36 */
37 struct dm_dev_internal {
38 struct list_head list;
39 atomic_t count;
40 struct dm_dev dm_dev;
41 };
42
43 struct dm_table;
44 struct dm_md_mempools;
45
46 /*-----------------------------------------------------------------
47 * Internal table functions.
48 *---------------------------------------------------------------*/
49 void dm_table_destroy(struct dm_table *t);
50 void dm_table_event_callback(struct dm_table *t,
51 void (*fn)(void *), void *context);
52 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
53 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
54 int dm_calculate_queue_limits(struct dm_table *table,
55 struct queue_limits *limits);
56 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
57 struct queue_limits *limits);
58 struct list_head *dm_table_get_devices(struct dm_table *t);
59 void dm_table_presuspend_targets(struct dm_table *t);
60 void dm_table_postsuspend_targets(struct dm_table *t);
61 int dm_table_resume_targets(struct dm_table *t);
62 int dm_table_any_congested(struct dm_table *t, int bdi_bits);
63 int dm_table_any_busy_target(struct dm_table *t);
64 unsigned dm_table_get_type(struct dm_table *t);
65 struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
66 bool dm_table_request_based(struct dm_table *t);
67 bool dm_table_supports_discards(struct dm_table *t);
68 int dm_table_alloc_md_mempools(struct dm_table *t);
69 void dm_table_free_md_mempools(struct dm_table *t);
70 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
71
72 int dm_queue_merge_is_compulsory(struct request_queue *q);
73
74 void dm_lock_md_type(struct mapped_device *md);
75 void dm_unlock_md_type(struct mapped_device *md);
76 void dm_set_md_type(struct mapped_device *md, unsigned type);
77 unsigned dm_get_md_type(struct mapped_device *md);
78 struct target_type *dm_get_immutable_target_type(struct mapped_device *md);
79
80 int dm_setup_md_queue(struct mapped_device *md);
81
82 /*
83 * To check the return value from dm_table_find_target().
84 */
85 #define dm_target_is_valid(t) ((t)->table)
86
87 /*
88 * To check whether the target type is request-based or not (bio-based).
89 */
90 #define dm_target_request_based(t) ((t)->type->map_rq != NULL)
91
92 /*-----------------------------------------------------------------
93 * A registry of target types.
94 *---------------------------------------------------------------*/
95 int dm_target_init(void);
96 void dm_target_exit(void);
97 struct target_type *dm_get_target_type(const char *name);
98 void dm_put_target_type(struct target_type *tt);
99 int dm_target_iterate(void (*iter_func)(struct target_type *tt,
100 void *param), void *param);
101
102 int dm_split_args(int *argc, char ***argvp, char *input);
103
104 /*
105 * Is this mapped_device being deleted?
106 */
107 int dm_deleting_md(struct mapped_device *md);
108
109 /*
110 * Is this mapped_device suspended?
111 */
112 int dm_suspended_md(struct mapped_device *md);
113
114 /*
115 * The device-mapper can be driven through one of two interfaces;
116 * ioctl or filesystem, depending which patch you have applied.
117 */
118 int dm_interface_init(void);
119 void dm_interface_exit(void);
120
121 /*
122 * sysfs interface
123 */
124 struct dm_kobject_holder {
125 struct kobject kobj;
126 struct completion completion;
127 };
128
dm_get_completion_from_kobject(struct kobject * kobj)129 static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
130 {
131 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
132 }
133
134 int dm_sysfs_init(struct mapped_device *md);
135 void dm_sysfs_exit(struct mapped_device *md);
136 struct kobject *dm_kobject(struct mapped_device *md);
137 struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
138
139 /*
140 * The kobject helper
141 */
142 void dm_kobject_release(struct kobject *kobj);
143
144 /*
145 * Targets for linear and striped mappings
146 */
147 int dm_linear_init(void);
148 void dm_linear_exit(void);
149
150 int dm_stripe_init(void);
151 void dm_stripe_exit(void);
152
153 /*
154 * mapped_device operations
155 */
156 void dm_destroy(struct mapped_device *md);
157 void dm_destroy_immediate(struct mapped_device *md);
158 int dm_open_count(struct mapped_device *md);
159 int dm_lock_for_deletion(struct mapped_device *md);
160
161 int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
162 unsigned cookie);
163
164 int dm_io_init(void);
165 void dm_io_exit(void);
166
167 int dm_kcopyd_init(void);
168 void dm_kcopyd_exit(void);
169
170 /*
171 * Mempool operations
172 */
173 struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity);
174 void dm_free_md_mempools(struct dm_md_mempools *pools);
175
176 #endif
177