]>
Commit | Line | Data |
---|---|---|
328970de | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
7063fbf2 JB |
2 | /* -*- mode: c; c-basic-offset: 8; -*- |
3 | * vim: noexpandtab sw=8 ts=8 sts=0: | |
4 | * | |
5 | * configfs.h - definitions for the device driver filesystem | |
6 | * | |
7063fbf2 JB |
7 | * Based on sysfs: |
8 | * sysfs is Copyright (C) 2001, 2002, 2003 Patrick Mochel | |
9 | * | |
10 | * Based on kobject.h: | |
11 | * Copyright (c) 2002-2003 Patrick Mochel | |
12 | * Copyright (c) 2002-2003 Open Source Development Labs | |
13 | * | |
14 | * configfs Copyright (C) 2005 Oracle. All rights reserved. | |
15 | * | |
55dff495 RD |
16 | * Please read Documentation/filesystems/configfs/configfs.txt before using |
17 | * the configfs interface, ESPECIALLY the parts about reference counts and | |
7063fbf2 JB |
18 | * item destructors. |
19 | */ | |
20 | ||
21 | #ifndef _CONFIGFS_H_ | |
22 | #define _CONFIGFS_H_ | |
23 | ||
a6ab5374 BVA |
24 | #include <linux/stat.h> /* S_IRUGO */ |
25 | #include <linux/types.h> /* ssize_t */ | |
26 | #include <linux/list.h> /* struct list_head */ | |
27 | #include <linux/kref.h> /* struct kref */ | |
28 | #include <linux/mutex.h> /* struct mutex */ | |
7063fbf2 JB |
29 | |
30 | #define CONFIGFS_ITEM_NAME_LEN 20 | |
31 | ||
32 | struct module; | |
33 | ||
34 | struct configfs_item_operations; | |
35 | struct configfs_group_operations; | |
36 | struct configfs_attribute; | |
03607ace | 37 | struct configfs_bin_attribute; |
7063fbf2 JB |
38 | struct configfs_subsystem; |
39 | ||
40 | struct config_item { | |
41 | char *ci_name; | |
42 | char ci_namebuf[CONFIGFS_ITEM_NAME_LEN]; | |
43 | struct kref ci_kref; | |
44 | struct list_head ci_entry; | |
45 | struct config_item *ci_parent; | |
46 | struct config_group *ci_group; | |
aa293583 | 47 | const struct config_item_type *ci_type; |
7063fbf2 JB |
48 | struct dentry *ci_dentry; |
49 | }; | |
50 | ||
8db14860 NI |
51 | extern __printf(2, 3) |
52 | int config_item_set_name(struct config_item *, const char *, ...); | |
7063fbf2 JB |
53 | |
54 | static inline char *config_item_name(struct config_item * item) | |
55 | { | |
56 | return item->ci_name; | |
57 | } | |
58 | ||
7063fbf2 JB |
59 | extern void config_item_init_type_name(struct config_item *item, |
60 | const char *name, | |
aa293583 | 61 | const struct config_item_type *type); |
7063fbf2 | 62 | |
19e72d3a BVA |
63 | extern struct config_item *config_item_get(struct config_item *); |
64 | extern struct config_item *config_item_get_unless_zero(struct config_item *); | |
7063fbf2 JB |
65 | extern void config_item_put(struct config_item *); |
66 | ||
67 | struct config_item_type { | |
68 | struct module *ct_owner; | |
69 | struct configfs_item_operations *ct_item_ops; | |
70 | struct configfs_group_operations *ct_group_ops; | |
71 | struct configfs_attribute **ct_attrs; | |
03607ace | 72 | struct configfs_bin_attribute **ct_bin_attrs; |
7063fbf2 JB |
73 | }; |
74 | ||
7063fbf2 JB |
75 | /** |
76 | * group - a group of config_items of a specific type, belonging | |
77 | * to a specific subsystem. | |
78 | */ | |
7063fbf2 JB |
79 | struct config_group { |
80 | struct config_item cg_item; | |
81 | struct list_head cg_children; | |
82 | struct configfs_subsystem *cg_subsys; | |
1ae1602d CH |
83 | struct list_head default_groups; |
84 | struct list_head group_entry; | |
7063fbf2 JB |
85 | }; |
86 | ||
7063fbf2 JB |
87 | extern void config_group_init(struct config_group *group); |
88 | extern void config_group_init_type_name(struct config_group *group, | |
89 | const char *name, | |
aa293583 | 90 | const struct config_item_type *type); |
7063fbf2 | 91 | |
7063fbf2 JB |
92 | static inline struct config_group *to_config_group(struct config_item *item) |
93 | { | |
94 | return item ? container_of(item,struct config_group,cg_item) : NULL; | |
95 | } | |
96 | ||
97 | static inline struct config_group *config_group_get(struct config_group *group) | |
98 | { | |
99 | return group ? to_config_group(config_item_get(&group->cg_item)) : NULL; | |
100 | } | |
101 | ||
102 | static inline void config_group_put(struct config_group *group) | |
103 | { | |
104 | config_item_put(&group->cg_item); | |
105 | } | |
106 | ||
3fe6c5ce SS |
107 | extern struct config_item *config_group_find_item(struct config_group *, |
108 | const char *); | |
7063fbf2 JB |
109 | |
110 | ||
1ae1602d CH |
111 | static inline void configfs_add_default_group(struct config_group *new_group, |
112 | struct config_group *group) | |
113 | { | |
114 | list_add_tail(&new_group->group_entry, &group->default_groups); | |
115 | } | |
116 | ||
7063fbf2 | 117 | struct configfs_attribute { |
3d0f89bb | 118 | const char *ca_name; |
7063fbf2 | 119 | struct module *ca_owner; |
43947514 | 120 | umode_t ca_mode; |
870823e6 CH |
121 | ssize_t (*show)(struct config_item *, char *); |
122 | ssize_t (*store)(struct config_item *, const char *, size_t); | |
7063fbf2 JB |
123 | }; |
124 | ||
870823e6 CH |
125 | #define CONFIGFS_ATTR(_pfx, _name) \ |
126 | static struct configfs_attribute _pfx##attr_##_name = { \ | |
127 | .ca_name = __stringify(_name), \ | |
128 | .ca_mode = S_IRUGO | S_IWUSR, \ | |
129 | .ca_owner = THIS_MODULE, \ | |
130 | .show = _pfx##_name##_show, \ | |
131 | .store = _pfx##_name##_store, \ | |
132 | } | |
133 | ||
134 | #define CONFIGFS_ATTR_RO(_pfx, _name) \ | |
135 | static struct configfs_attribute _pfx##attr_##_name = { \ | |
136 | .ca_name = __stringify(_name), \ | |
137 | .ca_mode = S_IRUGO, \ | |
138 | .ca_owner = THIS_MODULE, \ | |
139 | .show = _pfx##_name##_show, \ | |
140 | } | |
141 | ||
142 | #define CONFIGFS_ATTR_WO(_pfx, _name) \ | |
143 | static struct configfs_attribute _pfx##attr_##_name = { \ | |
144 | .ca_name = __stringify(_name), \ | |
145 | .ca_mode = S_IWUSR, \ | |
146 | .ca_owner = THIS_MODULE, \ | |
147 | .store = _pfx##_name##_store, \ | |
148 | } | |
149 | ||
03607ace PA |
150 | struct file; |
151 | struct vm_area_struct; | |
152 | ||
153 | struct configfs_bin_attribute { | |
154 | struct configfs_attribute cb_attr; /* std. attribute */ | |
155 | void *cb_private; /* for user */ | |
156 | size_t cb_max_size; /* max core size */ | |
157 | ssize_t (*read)(struct config_item *, void *, size_t); | |
158 | ssize_t (*write)(struct config_item *, const void *, size_t); | |
159 | }; | |
160 | ||
161 | #define CONFIGFS_BIN_ATTR(_pfx, _name, _priv, _maxsz) \ | |
162 | static struct configfs_bin_attribute _pfx##attr_##_name = { \ | |
163 | .cb_attr = { \ | |
164 | .ca_name = __stringify(_name), \ | |
165 | .ca_mode = S_IRUGO | S_IWUSR, \ | |
166 | .ca_owner = THIS_MODULE, \ | |
167 | }, \ | |
168 | .cb_private = _priv, \ | |
169 | .cb_max_size = _maxsz, \ | |
170 | .read = _pfx##_name##_read, \ | |
171 | .write = _pfx##_name##_write, \ | |
172 | } | |
173 | ||
174 | #define CONFIGFS_BIN_ATTR_RO(_pfx, _name, _priv, _maxsz) \ | |
96c22a32 | 175 | static struct configfs_bin_attribute _pfx##attr_##_name = { \ |
03607ace PA |
176 | .cb_attr = { \ |
177 | .ca_name = __stringify(_name), \ | |
178 | .ca_mode = S_IRUGO, \ | |
179 | .ca_owner = THIS_MODULE, \ | |
180 | }, \ | |
181 | .cb_private = _priv, \ | |
182 | .cb_max_size = _maxsz, \ | |
183 | .read = _pfx##_name##_read, \ | |
184 | } | |
185 | ||
186 | #define CONFIGFS_BIN_ATTR_WO(_pfx, _name, _priv, _maxsz) \ | |
96c22a32 | 187 | static struct configfs_bin_attribute _pfx##attr_##_name = { \ |
03607ace PA |
188 | .cb_attr = { \ |
189 | .ca_name = __stringify(_name), \ | |
190 | .ca_mode = S_IWUSR, \ | |
191 | .ca_owner = THIS_MODULE, \ | |
192 | }, \ | |
193 | .cb_private = _priv, \ | |
194 | .cb_max_size = _maxsz, \ | |
195 | .write = _pfx##_name##_write, \ | |
196 | } | |
197 | ||
7063fbf2 JB |
198 | /* |
199 | * If allow_link() exists, the item can symlink(2) out to other | |
200 | * items. If the item is a group, it may support mkdir(2). | |
201 | * Groups supply one of make_group() and make_item(). If the | |
202 | * group supports make_group(), one can create group children. If it | |
a6795e9e JB |
203 | * supports make_item(), one can create config_item children. make_group() |
204 | * and make_item() return ERR_PTR() on errors. If it has | |
7063fbf2 JB |
205 | * default_groups on group->default_groups, it has automatically created |
206 | * group children. default_groups may coexist alongsize make_group() or | |
207 | * make_item(), but if the group wishes to have only default_groups | |
208 | * children (disallowing mkdir(2)), it need not provide either function. | |
25985edc | 209 | * If the group has commit(), it supports pending and committed (active) |
7063fbf2 JB |
210 | * items. |
211 | */ | |
212 | struct configfs_item_operations { | |
213 | void (*release)(struct config_item *); | |
7063fbf2 | 214 | int (*allow_link)(struct config_item *src, struct config_item *target); |
e16769d4 | 215 | void (*drop_link)(struct config_item *src, struct config_item *target); |
7063fbf2 JB |
216 | }; |
217 | ||
218 | struct configfs_group_operations { | |
f89ab861 JB |
219 | struct config_item *(*make_item)(struct config_group *group, const char *name); |
220 | struct config_group *(*make_group)(struct config_group *group, const char *name); | |
7063fbf2 | 221 | int (*commit_item)(struct config_item *item); |
299894cc | 222 | void (*disconnect_notify)(struct config_group *group, struct config_item *item); |
7063fbf2 JB |
223 | void (*drop_item)(struct config_group *group, struct config_item *item); |
224 | }; | |
225 | ||
7063fbf2 JB |
226 | struct configfs_subsystem { |
227 | struct config_group su_group; | |
e6bd07ae | 228 | struct mutex su_mutex; |
7063fbf2 JB |
229 | }; |
230 | ||
231 | static inline struct configfs_subsystem *to_configfs_subsystem(struct config_group *group) | |
232 | { | |
233 | return group ? | |
234 | container_of(group, struct configfs_subsystem, su_group) : | |
235 | NULL; | |
236 | } | |
237 | ||
238 | int configfs_register_subsystem(struct configfs_subsystem *subsys); | |
239 | void configfs_unregister_subsystem(struct configfs_subsystem *subsys); | |
240 | ||
5cf6a51e DB |
241 | int configfs_register_group(struct config_group *parent_group, |
242 | struct config_group *group); | |
243 | void configfs_unregister_group(struct config_group *group); | |
244 | ||
1ae1602d CH |
245 | void configfs_remove_default_groups(struct config_group *group); |
246 | ||
5cf6a51e DB |
247 | struct config_group * |
248 | configfs_register_default_group(struct config_group *parent_group, | |
249 | const char *name, | |
aa293583 | 250 | const struct config_item_type *item_type); |
5cf6a51e DB |
251 | void configfs_unregister_default_group(struct config_group *group); |
252 | ||
631d1feb JB |
253 | /* These functions can sleep and can alloc with GFP_KERNEL */ |
254 | /* WARNING: These cannot be called underneath configfs callbacks!! */ | |
9a9e3415 KO |
255 | int configfs_depend_item(struct configfs_subsystem *subsys, |
256 | struct config_item *target); | |
257 | void configfs_undepend_item(struct config_item *target); | |
631d1feb | 258 | |
d79d75b5 KO |
259 | /* |
260 | * These functions can sleep and can alloc with GFP_KERNEL | |
261 | * NOTE: These should be called only underneath configfs callbacks. | |
262 | * NOTE: First parameter is a caller's subsystem, not target's. | |
263 | * WARNING: These cannot be called on newly created item | |
264 | * (in make_group()/make_item() callback) | |
265 | */ | |
266 | int configfs_depend_item_unlocked(struct configfs_subsystem *caller_subsys, | |
267 | struct config_item *target); | |
268 | ||
269 | ||
270 | static inline void configfs_undepend_item_unlocked(struct config_item *target) | |
271 | { | |
272 | configfs_undepend_item(target); | |
273 | } | |
631d1feb | 274 | |
7063fbf2 | 275 | #endif /* _CONFIGFS_H_ */ |