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 * Status feature flags
29 */
30 #define DM_STATUS_NOFLUSH_FLAG (1 << 0)
31
32 /*
33 * Type of table and mapped_device's mempool
34 */
35 #define DM_TYPE_NONE 0
36 #define DM_TYPE_BIO_BASED 1
37 #define DM_TYPE_REQUEST_BASED 2
38
39 /*
40 * List of devices that a metadevice uses and should open/close.
41 */
42 struct dm_dev_internal {
43 struct list_head list;
44 atomic_t count;
45 struct dm_dev dm_dev;
46 };
47
48 struct dm_table;
49 struct dm_md_mempools;
50
51 /*-----------------------------------------------------------------
52 * Internal table functions.
53 *---------------------------------------------------------------*/
54 void dm_table_destroy(struct dm_table *t);
55 void dm_table_event_callback(struct dm_table *t,
56 void (*fn)(void *), void *context);
57 struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
58 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
59 bool dm_table_has_no_data_devices(struct dm_table *table);
60 int dm_calculate_queue_limits(struct dm_table *table,
61 struct queue_limits *limits);
62 void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
63 struct queue_limits *limits);
64 struct list_head *dm_table_get_devices(struct dm_table *t);
65 void dm_table_presuspend_targets(struct dm_table *t);
66 void dm_table_postsuspend_targets(struct dm_table *t);
67 int dm_table_resume_targets(struct dm_table *t);
68 int dm_table_any_congested(struct dm_table *t, int bdi_bits);
69 int dm_table_any_busy_target(struct dm_table *t);
70 unsigned dm_table_get_type(struct dm_table *t);
71 struct target_type *dm_table_get_immutable_target_type(struct dm_table *t);
72 bool dm_table_request_based(struct dm_table *t);
73 bool dm_table_supports_discards(struct dm_table *t);
74 int dm_table_alloc_md_mempools(struct dm_table *t);
75 void dm_table_free_md_mempools(struct dm_table *t);
76 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
77
78 int dm_queue_merge_is_compulsory(struct request_queue *q);
79
80 void dm_lock_md_type(struct mapped_device *md);
81 void dm_unlock_md_type(struct mapped_device *md);
82 void dm_set_md_type(struct mapped_device *md, unsigned type);
83 unsigned dm_get_md_type(struct mapped_device *md);
84 struct target_type *dm_get_immutable_target_type(struct mapped_device *md);
85
86 int dm_setup_md_queue(struct mapped_device *md);
87
88 /*
89 * To check the return value from dm_table_find_target().
90 */
91 #define dm_target_is_valid(t) ((t)->table)
92
93 /*
94 * To check whether the target type is request-based or not (bio-based).
95 */
96 #define dm_target_request_based(t) ((t)->type->map_rq != NULL)
97
98 /*-----------------------------------------------------------------
99 * A registry of target types.
100 *---------------------------------------------------------------*/
101 int dm_target_init(void);
102 void dm_target_exit(void);
103 struct target_type *dm_get_target_type(const char *name);
104 void dm_put_target_type(struct target_type *tt);
105 int dm_target_iterate(void (*iter_func)(struct target_type *tt,
106 void *param), void *param);
107
108 int dm_split_args(int *argc, char ***argvp, char *input);
109
110 /*
111 * Is this mapped_device being deleted?
112 */
113 int dm_deleting_md(struct mapped_device *md);
114
115 /*
116 * Is this mapped_device suspended?
117 */
118 int dm_suspended_md(struct mapped_device *md);
119
120 /*
121 * The device-mapper can be driven through one of two interfaces;
122 * ioctl or filesystem, depending which patch you have applied.
123 */
124 int dm_interface_init(void);
125 void dm_interface_exit(void);
126
127 /*
128 * sysfs interface
129 */
130 struct dm_kobject_holder {
131 struct kobject kobj;
132 struct completion completion;
133 };
134
dm_get_completion_from_kobject(struct kobject * kobj)135 static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
136 {
137 return &container_of(kobj, struct dm_kobject_holder, kobj)->completion;
138 }
139
140 int dm_sysfs_init(struct mapped_device *md);
141 void dm_sysfs_exit(struct mapped_device *md);
142 struct kobject *dm_kobject(struct mapped_device *md);
143 struct mapped_device *dm_get_from_kobject(struct kobject *kobj);
144
145 /*
146 * The kobject helper
147 */
148 void dm_kobject_release(struct kobject *kobj);
149
150 /*
151 * Targets for linear and striped mappings
152 */
153 int dm_linear_init(void);
154 void dm_linear_exit(void);
155
156 int dm_stripe_init(void);
157 void dm_stripe_exit(void);
158
159 /*
160 * mapped_device operations
161 */
162 void dm_destroy(struct mapped_device *md);
163 void dm_destroy_immediate(struct mapped_device *md);
164 int dm_open_count(struct mapped_device *md);
165 int dm_lock_for_deletion(struct mapped_device *md);
166
167 int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
168 unsigned cookie);
169
170 int dm_io_init(void);
171 void dm_io_exit(void);
172
173 int dm_kcopyd_init(void);
174 void dm_kcopyd_exit(void);
175
176 /*
177 * Mempool operations
178 */
179 struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, unsigned per_bio_data_size);
180 void dm_free_md_mempools(struct dm_md_mempools *pools);
181
182 #endif
183