1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
4 * configfs.h - definitions for the device driver filesystem
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
16 * You should have received a copy of the GNU General Public
17 * License along with this program; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 021110-1307, USA.
22 * sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel
25 * Copyright (c) 2002-2003 Patrick Mochel
26 * Copyright (c) 2002-2003 Open Source Development Labs
28 * configfs Copyright (C) 2005 Oracle. All rights reserved.
30 * Please read Documentation/filesystems/configfs/configfs.txt before using
31 * the configfs interface, ESPECIALLY the parts about reference counts and
38 #include <linux/kernel.h>
39 #include <linux/types.h>
40 #include <linux/list.h>
41 #include <linux/kref.h>
42 #include <linux/mutex.h>
43 #include <linux/err.h>
45 #include <linux/atomic.h>
47 #define CONFIGFS_ITEM_NAME_LEN 20
51 struct configfs_item_operations
;
52 struct configfs_group_operations
;
53 struct configfs_attribute
;
54 struct configfs_subsystem
;
58 char ci_namebuf
[CONFIGFS_ITEM_NAME_LEN
];
60 struct list_head ci_entry
;
61 struct config_item
*ci_parent
;
62 struct config_group
*ci_group
;
63 struct config_item_type
*ci_type
;
64 struct dentry
*ci_dentry
;
68 int config_item_set_name(struct config_item
*, const char *, ...);
70 static inline char *config_item_name(struct config_item
* item
)
75 extern void config_item_init_type_name(struct config_item
*item
,
77 struct config_item_type
*type
);
79 extern struct config_item
* config_item_get(struct config_item
*);
80 extern void config_item_put(struct config_item
*);
82 struct config_item_type
{
83 struct module
*ct_owner
;
84 struct configfs_item_operations
*ct_item_ops
;
85 struct configfs_group_operations
*ct_group_ops
;
86 struct configfs_attribute
**ct_attrs
;
90 * group - a group of config_items of a specific type, belonging
91 * to a specific subsystem.
94 struct config_item cg_item
;
95 struct list_head cg_children
;
96 struct configfs_subsystem
*cg_subsys
;
97 struct config_group
**default_groups
;
100 extern void config_group_init(struct config_group
*group
);
101 extern void config_group_init_type_name(struct config_group
*group
,
103 struct config_item_type
*type
);
105 static inline struct config_group
*to_config_group(struct config_item
*item
)
107 return item
? container_of(item
,struct config_group
,cg_item
) : NULL
;
110 static inline struct config_group
*config_group_get(struct config_group
*group
)
112 return group
? to_config_group(config_item_get(&group
->cg_item
)) : NULL
;
115 static inline void config_group_put(struct config_group
*group
)
117 config_item_put(&group
->cg_item
);
120 extern struct config_item
*config_group_find_item(struct config_group
*,
124 struct configfs_attribute
{
126 struct module
*ca_owner
;
128 ssize_t (*show
)(struct config_item
*, char *);
129 ssize_t (*store
)(struct config_item
*, const char *, size_t);
132 #define CONFIGFS_ATTR(_pfx, _name) \
133 static struct configfs_attribute _pfx##attr_##_name = { \
134 .ca_name = __stringify(_name), \
135 .ca_mode = S_IRUGO | S_IWUSR, \
136 .ca_owner = THIS_MODULE, \
137 .show = _pfx##_name##_show, \
138 .store = _pfx##_name##_store, \
141 #define CONFIGFS_ATTR_RO(_pfx, _name) \
142 static struct configfs_attribute _pfx##attr_##_name = { \
143 .ca_name = __stringify(_name), \
144 .ca_mode = S_IRUGO, \
145 .ca_owner = THIS_MODULE, \
146 .show = _pfx##_name##_show, \
149 #define CONFIGFS_ATTR_WO(_pfx, _name) \
150 static struct configfs_attribute _pfx##attr_##_name = { \
151 .ca_name = __stringify(_name), \
152 .ca_mode = S_IWUSR, \
153 .ca_owner = THIS_MODULE, \
154 .store = _pfx##_name##_store, \
158 * If allow_link() exists, the item can symlink(2) out to other
159 * items. If the item is a group, it may support mkdir(2).
160 * Groups supply one of make_group() and make_item(). If the
161 * group supports make_group(), one can create group children. If it
162 * supports make_item(), one can create config_item children. make_group()
163 * and make_item() return ERR_PTR() on errors. If it has
164 * default_groups on group->default_groups, it has automatically created
165 * group children. default_groups may coexist alongsize make_group() or
166 * make_item(), but if the group wishes to have only default_groups
167 * children (disallowing mkdir(2)), it need not provide either function.
168 * If the group has commit(), it supports pending and committed (active)
171 struct configfs_item_operations
{
172 void (*release
)(struct config_item
*);
173 int (*allow_link
)(struct config_item
*src
, struct config_item
*target
);
174 int (*drop_link
)(struct config_item
*src
, struct config_item
*target
);
177 struct configfs_group_operations
{
178 struct config_item
*(*make_item
)(struct config_group
*group
, const char *name
);
179 struct config_group
*(*make_group
)(struct config_group
*group
, const char *name
);
180 int (*commit_item
)(struct config_item
*item
);
181 void (*disconnect_notify
)(struct config_group
*group
, struct config_item
*item
);
182 void (*drop_item
)(struct config_group
*group
, struct config_item
*item
);
185 struct configfs_subsystem
{
186 struct config_group su_group
;
187 struct mutex su_mutex
;
190 static inline struct configfs_subsystem
*to_configfs_subsystem(struct config_group
*group
)
193 container_of(group
, struct configfs_subsystem
, su_group
) :
197 int configfs_register_subsystem(struct configfs_subsystem
*subsys
);
198 void configfs_unregister_subsystem(struct configfs_subsystem
*subsys
);
200 /* These functions can sleep and can alloc with GFP_KERNEL */
201 /* WARNING: These cannot be called underneath configfs callbacks!! */
202 int configfs_depend_item(struct configfs_subsystem
*subsys
, struct config_item
*target
);
203 void configfs_undepend_item(struct configfs_subsystem
*subsys
, struct config_item
*target
);
205 #endif /* _CONFIGFS_H_ */