1 /*
2 * fs/sysfs/sysfs.h - sysfs internal header file
3 *
4 * Copyright (c) 2001-3 Patrick Mochel
5 * Copyright (c) 2007 SUSE Linux Products GmbH
6 * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
7 *
8 * This file is released under the GPLv2.
9 */
10
11 struct sysfs_open_dirent;
12
13 /* type-specific structures for sysfs_dirent->s_* union members */
14 struct sysfs_elem_dir {
15 struct kobject *kobj;
16 /* children list starts here and goes through sd->s_sibling */
17 struct sysfs_dirent *children;
18 };
19
20 struct sysfs_elem_symlink {
21 struct sysfs_dirent *target_sd;
22 };
23
24 struct sysfs_elem_attr {
25 struct attribute *attr;
26 struct sysfs_open_dirent *open;
27 };
28
29 struct sysfs_elem_bin_attr {
30 struct bin_attribute *bin_attr;
31 };
32
33 /*
34 * sysfs_dirent - the building block of sysfs hierarchy. Each and
35 * every sysfs node is represented by single sysfs_dirent.
36 *
37 * As long as s_count reference is held, the sysfs_dirent itself is
38 * accessible. Dereferencing s_elem or any other outer entity
39 * requires s_active reference.
40 */
41 struct sysfs_dirent {
42 atomic_t s_count;
43 atomic_t s_active;
44 struct sysfs_dirent *s_parent;
45 struct sysfs_dirent *s_sibling;
46 const char *s_name;
47
48 union {
49 struct sysfs_elem_dir s_dir;
50 struct sysfs_elem_symlink s_symlink;
51 struct sysfs_elem_attr s_attr;
52 struct sysfs_elem_bin_attr s_bin_attr;
53 };
54
55 unsigned int s_flags;
56 ino_t s_ino;
57 umode_t s_mode;
58 struct iattr *s_iattr;
59 };
60
61 #define SD_DEACTIVATED_BIAS INT_MIN
62
63 #define SYSFS_TYPE_MASK 0x00ff
64 #define SYSFS_DIR 0x0001
65 #define SYSFS_KOBJ_ATTR 0x0002
66 #define SYSFS_KOBJ_BIN_ATTR 0x0004
67 #define SYSFS_KOBJ_LINK 0x0008
68 #define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK)
69
70 #define SYSFS_FLAG_MASK ~SYSFS_TYPE_MASK
71 #define SYSFS_FLAG_REMOVED 0x0200
72
sysfs_type(struct sysfs_dirent * sd)73 static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
74 {
75 return sd->s_flags & SYSFS_TYPE_MASK;
76 }
77
78 /*
79 * Context structure to be used while adding/removing nodes.
80 */
81 struct sysfs_addrm_cxt {
82 struct sysfs_dirent *parent_sd;
83 struct inode *parent_inode;
84 struct sysfs_dirent *removed;
85 int cnt;
86 };
87
88 /*
89 * mount.c
90 */
91 extern struct sysfs_dirent sysfs_root;
92 extern struct super_block *sysfs_sb;
93 extern struct kmem_cache *sysfs_dir_cachep;
94
95 /*
96 * dir.c
97 */
98 extern struct mutex sysfs_mutex;
99 extern struct mutex sysfs_rename_mutex;
100 extern spinlock_t sysfs_assoc_lock;
101
102 extern const struct file_operations sysfs_dir_operations;
103 extern const struct inode_operations sysfs_dir_inode_operations;
104
105 struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
106 struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd);
107 void sysfs_put_active_two(struct sysfs_dirent *sd);
108 void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
109 struct sysfs_dirent *parent_sd);
110 int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
111 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
112 void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
113 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
114
115 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
116 const unsigned char *name);
117 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
118 const unsigned char *name);
119 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type);
120
121 void release_sysfs_dirent(struct sysfs_dirent *sd);
122
123 int sysfs_create_subdir(struct kobject *kobj, const char *name,
124 struct sysfs_dirent **p_sd);
125 void sysfs_remove_subdir(struct sysfs_dirent *sd);
126
__sysfs_get(struct sysfs_dirent * sd)127 static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd)
128 {
129 if (sd) {
130 WARN_ON(!atomic_read(&sd->s_count));
131 atomic_inc(&sd->s_count);
132 }
133 return sd;
134 }
135 #define sysfs_get(sd) __sysfs_get(sd)
136
__sysfs_put(struct sysfs_dirent * sd)137 static inline void __sysfs_put(struct sysfs_dirent *sd)
138 {
139 if (sd && atomic_dec_and_test(&sd->s_count))
140 release_sysfs_dirent(sd);
141 }
142 #define sysfs_put(sd) __sysfs_put(sd)
143
144 /*
145 * inode.c
146 */
147 struct inode *sysfs_get_inode(struct sysfs_dirent *sd);
148 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
149 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
150 int sysfs_inode_init(void);
151
152 /*
153 * file.c
154 */
155 extern const struct file_operations sysfs_file_operations;
156
157 int sysfs_add_file(struct sysfs_dirent *dir_sd,
158 const struct attribute *attr, int type);
159
160 int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
161 const struct attribute *attr, int type, mode_t amode);
162 /*
163 * bin.c
164 */
165 extern const struct file_operations bin_fops;
166
167 /*
168 * symlink.c
169 */
170 extern const struct inode_operations sysfs_symlink_inode_operations;
171