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/stat.h> /* S_IRUGO */
39 #include <linux/types.h> /* ssize_t */
40 #include <linux/list.h> /* struct list_head */
41 #include <linux/kref.h> /* struct kref */
42 #include <linux/mutex.h> /* struct mutex */
44 #define CONFIGFS_ITEM_NAME_LEN 20
48 struct configfs_item_operations;
49 struct configfs_group_operations;
50 struct configfs_attribute;
51 struct configfs_bin_attribute;
52 struct configfs_subsystem;
56 char ci_namebuf[CONFIGFS_ITEM_NAME_LEN];
58 struct list_head ci_entry;
59 struct config_item *ci_parent;
60 struct config_group *ci_group;
61 struct config_item_type *ci_type;
62 struct dentry *ci_dentry;
66 int config_item_set_name(struct config_item *, const char *, ...);
68 static inline char *config_item_name(struct config_item * item)
73 extern void config_item_init_type_name(struct config_item *item,
75 struct config_item_type *type);
77 extern struct config_item * config_item_get(struct config_item *);
78 extern void config_item_put(struct config_item *);
80 struct config_item_type {
81 struct module *ct_owner;
82 struct configfs_item_operations *ct_item_ops;
83 struct configfs_group_operations *ct_group_ops;
84 struct configfs_attribute **ct_attrs;
85 struct configfs_bin_attribute **ct_bin_attrs;
89 * group - a group of config_items of a specific type, belonging
90 * to a specific subsystem.
93 struct config_item cg_item;
94 struct list_head cg_children;
95 struct configfs_subsystem *cg_subsys;
96 struct list_head default_groups;
97 struct list_head group_entry;
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 static inline void configfs_add_default_group(struct config_group *new_group,
125 struct config_group *group)
127 list_add_tail(&new_group->group_entry, &group->default_groups);
130 struct configfs_attribute {
132 struct module *ca_owner;
134 ssize_t (*show)(struct config_item *, char *);
135 ssize_t (*store)(struct config_item *, const char *, size_t);
138 #define CONFIGFS_ATTR(_pfx, _name) \
139 static struct configfs_attribute _pfx##attr_##_name = { \
140 .ca_name = __stringify(_name), \
141 .ca_mode = S_IRUGO | S_IWUSR, \
142 .ca_owner = THIS_MODULE, \
143 .show = _pfx##_name##_show, \
144 .store = _pfx##_name##_store, \
147 #define CONFIGFS_ATTR_RO(_pfx, _name) \
148 static struct configfs_attribute _pfx##attr_##_name = { \
149 .ca_name = __stringify(_name), \
150 .ca_mode = S_IRUGO, \
151 .ca_owner = THIS_MODULE, \
152 .show = _pfx##_name##_show, \
155 #define CONFIGFS_ATTR_WO(_pfx, _name) \
156 static struct configfs_attribute _pfx##attr_##_name = { \
157 .ca_name = __stringify(_name), \
158 .ca_mode = S_IWUSR, \
159 .ca_owner = THIS_MODULE, \
160 .store = _pfx##_name##_store, \
164 struct vm_area_struct;
166 struct configfs_bin_attribute {
167 struct configfs_attribute cb_attr; /* std. attribute */
168 void *cb_private; /* for user */
169 size_t cb_max_size; /* max core size */
170 ssize_t (*read)(struct config_item *, void *, size_t);
171 ssize_t (*write)(struct config_item *, const void *, size_t);
174 #define CONFIGFS_BIN_ATTR(_pfx, _name, _priv, _maxsz) \
175 static struct configfs_bin_attribute _pfx##attr_##_name = { \
177 .ca_name = __stringify(_name), \
178 .ca_mode = S_IRUGO | S_IWUSR, \
179 .ca_owner = THIS_MODULE, \
181 .cb_private = _priv, \
182 .cb_max_size = _maxsz, \
183 .read = _pfx##_name##_read, \
184 .write = _pfx##_name##_write, \
187 #define CONFIGFS_BIN_ATTR_RO(_pfx, _name, _priv, _maxsz) \
188 static struct configfs_bin_attribute _pfx##attr_##_name = { \
190 .ca_name = __stringify(_name), \
191 .ca_mode = S_IRUGO, \
192 .ca_owner = THIS_MODULE, \
194 .cb_private = _priv, \
195 .cb_max_size = _maxsz, \
196 .read = _pfx##_name##_read, \
199 #define CONFIGFS_BIN_ATTR_WO(_pfx, _name, _priv, _maxsz) \
200 static struct configfs_bin_attribute _pfx##attr_##_name = { \
202 .ca_name = __stringify(_name), \
203 .ca_mode = S_IWUSR, \
204 .ca_owner = THIS_MODULE, \
206 .cb_private = _priv, \
207 .cb_max_size = _maxsz, \
208 .write = _pfx##_name##_write, \
212 * If allow_link() exists, the item can symlink(2) out to other
213 * items. If the item is a group, it may support mkdir(2).
214 * Groups supply one of make_group() and make_item(). If the
215 * group supports make_group(), one can create group children. If it
216 * supports make_item(), one can create config_item children. make_group()
217 * and make_item() return ERR_PTR() on errors. If it has
218 * default_groups on group->default_groups, it has automatically created
219 * group children. default_groups may coexist alongsize make_group() or
220 * make_item(), but if the group wishes to have only default_groups
221 * children (disallowing mkdir(2)), it need not provide either function.
222 * If the group has commit(), it supports pending and committed (active)
225 struct configfs_item_operations {
226 void (*release)(struct config_item *);
227 int (*allow_link)(struct config_item *src, struct config_item *target);
228 void (*drop_link)(struct config_item *src, struct config_item *target);
231 struct configfs_group_operations {
232 struct config_item *(*make_item)(struct config_group *group, const char *name);
233 struct config_group *(*make_group)(struct config_group *group, const char *name);
234 int (*commit_item)(struct config_item *item);
235 void (*disconnect_notify)(struct config_group *group, struct config_item *item);
236 void (*drop_item)(struct config_group *group, struct config_item *item);
239 struct configfs_subsystem {
240 struct config_group su_group;
241 struct mutex su_mutex;
244 static inline struct configfs_subsystem *to_configfs_subsystem(struct config_group *group)
247 container_of(group, struct configfs_subsystem, su_group) :
251 int configfs_register_subsystem(struct configfs_subsystem *subsys);
252 void configfs_unregister_subsystem(struct configfs_subsystem *subsys);
254 int configfs_register_group(struct config_group *parent_group,
255 struct config_group *group);
256 void configfs_unregister_group(struct config_group *group);
258 void configfs_remove_default_groups(struct config_group *group);
260 struct config_group *
261 configfs_register_default_group(struct config_group *parent_group,
263 struct config_item_type *item_type);
264 void configfs_unregister_default_group(struct config_group *group);
266 /* These functions can sleep and can alloc with GFP_KERNEL */
267 /* WARNING: These cannot be called underneath configfs callbacks!! */
268 int configfs_depend_item(struct configfs_subsystem *subsys,
269 struct config_item *target);
270 void configfs_undepend_item(struct config_item *target);
273 * These functions can sleep and can alloc with GFP_KERNEL
274 * NOTE: These should be called only underneath configfs callbacks.
275 * NOTE: First parameter is a caller's subsystem, not target's.
276 * WARNING: These cannot be called on newly created item
277 * (in make_group()/make_item() callback)
279 int configfs_depend_item_unlocked(struct configfs_subsystem *caller_subsys,
280 struct config_item *target);
283 static inline void configfs_undepend_item_unlocked(struct config_item *target)
285 configfs_undepend_item(target);
288 #endif /* _CONFIGFS_H_ */