xref: /openbmc/linux/fs/sysfs/sysfs.h (revision aecdceda)
1 struct sysfs_elem_dir {
2 	struct kobject		* kobj;
3 };
4 
5 struct sysfs_elem_symlink {
6 	struct kobject		* target_kobj;
7 };
8 
9 struct sysfs_elem_attr {
10 	struct attribute	* attr;
11 };
12 
13 struct sysfs_elem_bin_attr {
14 	struct bin_attribute	* bin_attr;
15 };
16 
17 struct sysfs_dirent {
18 	atomic_t		s_count;
19 	struct sysfs_dirent	* s_parent;
20 	struct list_head	s_sibling;
21 	struct list_head	s_children;
22 	const char		* s_name;
23 
24 	union {
25 		struct sysfs_elem_dir		dir;
26 		struct sysfs_elem_symlink	symlink;
27 		struct sysfs_elem_attr		attr;
28 		struct sysfs_elem_bin_attr	bin_attr;
29 	}			s_elem;
30 
31 	int			s_type;
32 	umode_t			s_mode;
33 	ino_t			s_ino;
34 	struct dentry		* s_dentry;
35 	struct iattr		* s_iattr;
36 	atomic_t		s_event;
37 };
38 
39 extern struct vfsmount * sysfs_mount;
40 extern struct kmem_cache *sysfs_dir_cachep;
41 
42 extern void sysfs_delete_inode(struct inode *inode);
43 extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *);
44 extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
45 
46 extern void release_sysfs_dirent(struct sysfs_dirent * sd);
47 extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *);
48 extern struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode,
49 					     int type);
50 extern void sysfs_attach_dirent(struct sysfs_dirent *sd,
51 				struct sysfs_dirent *parent_sd,
52 				struct dentry *dentry);
53 
54 extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
55 extern int sysfs_hash_and_remove(struct dentry * dir, const char * name);
56 extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);
57 
58 extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);
59 extern void sysfs_remove_subdir(struct dentry *);
60 
61 extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent);
62 extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
63 
64 extern spinlock_t sysfs_lock;
65 extern spinlock_t kobj_sysfs_assoc_lock;
66 extern struct rw_semaphore sysfs_rename_sem;
67 extern struct super_block * sysfs_sb;
68 extern const struct file_operations sysfs_dir_operations;
69 extern const struct file_operations sysfs_file_operations;
70 extern const struct file_operations bin_fops;
71 extern const struct inode_operations sysfs_dir_inode_operations;
72 extern const struct inode_operations sysfs_symlink_inode_operations;
73 
74 struct sysfs_buffer {
75 	struct list_head		associates;
76 	size_t				count;
77 	loff_t				pos;
78 	char				* page;
79 	struct sysfs_ops		* ops;
80 	struct semaphore		sem;
81 	int				orphaned;
82 	int				needs_read_fill;
83 	int				event;
84 };
85 
86 struct sysfs_buffer_collection {
87 	struct list_head	associates;
88 };
89 
90 static inline struct kobject * to_kobj(struct dentry * dentry)
91 {
92 	struct sysfs_dirent * sd = dentry->d_fsdata;
93 	return sd->s_elem.dir.kobj;
94 }
95 
96 static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)
97 {
98 	struct kobject * kobj = NULL;
99 
100 	spin_lock(&dcache_lock);
101 	if (!d_unhashed(dentry)) {
102 		struct sysfs_dirent * sd = dentry->d_fsdata;
103 		if (sd->s_type & SYSFS_KOBJ_LINK)
104 			kobj = kobject_get(sd->s_elem.symlink.target_kobj);
105 		else
106 			kobj = kobject_get(sd->s_elem.dir.kobj);
107 	}
108 	spin_unlock(&dcache_lock);
109 
110 	return kobj;
111 }
112 
113 static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
114 {
115 	if (sd) {
116 		WARN_ON(!atomic_read(&sd->s_count));
117 		atomic_inc(&sd->s_count);
118 	}
119 	return sd;
120 }
121 
122 static inline void sysfs_put(struct sysfs_dirent * sd)
123 {
124 	if (sd && atomic_dec_and_test(&sd->s_count))
125 		release_sysfs_dirent(sd);
126 }
127 
128 static inline int sysfs_is_shadowed_inode(struct inode *inode)
129 {
130 	return S_ISDIR(inode->i_mode) && inode->i_op->follow_link;
131 }
132