xref: /openbmc/linux/fs/sysfs/sysfs.h (revision e868d61272caa648214046a096e5a6bfc068dc8c)
1 struct sysfs_dirent {
2 	atomic_t		s_count;
3 	struct list_head	s_sibling;
4 	struct list_head	s_children;
5 	void 			* s_element;
6 	int			s_type;
7 	umode_t			s_mode;
8 	struct dentry		* s_dentry;
9 	struct iattr		* s_iattr;
10 	atomic_t		s_event;
11 };
12 
13 extern struct vfsmount * sysfs_mount;
14 extern struct kmem_cache *sysfs_dir_cachep;
15 
16 extern void sysfs_delete_inode(struct inode *inode);
17 extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *);
18 extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
19 
20 extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *);
21 extern int sysfs_make_dirent(struct sysfs_dirent *, struct dentry *, void *,
22 				umode_t, int);
23 
24 extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
25 extern int sysfs_hash_and_remove(struct dentry * dir, const char * name);
26 extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);
27 
28 extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);
29 extern void sysfs_remove_subdir(struct dentry *);
30 
31 extern const unsigned char * sysfs_get_name(struct sysfs_dirent *sd);
32 extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent);
33 extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
34 
35 extern struct rw_semaphore sysfs_rename_sem;
36 extern struct super_block * sysfs_sb;
37 extern const struct file_operations sysfs_dir_operations;
38 extern const struct file_operations sysfs_file_operations;
39 extern const struct file_operations bin_fops;
40 extern const struct inode_operations sysfs_dir_inode_operations;
41 extern const struct inode_operations sysfs_symlink_inode_operations;
42 
43 struct sysfs_symlink {
44 	char * link_name;
45 	struct kobject * target_kobj;
46 };
47 
48 struct sysfs_buffer {
49 	struct list_head		associates;
50 	size_t				count;
51 	loff_t				pos;
52 	char				* page;
53 	struct sysfs_ops		* ops;
54 	struct semaphore		sem;
55 	int				orphaned;
56 	int				needs_read_fill;
57 	int				event;
58 };
59 
60 struct sysfs_buffer_collection {
61 	struct list_head	associates;
62 };
63 
64 static inline struct kobject * to_kobj(struct dentry * dentry)
65 {
66 	struct sysfs_dirent * sd = dentry->d_fsdata;
67 	return ((struct kobject *) sd->s_element);
68 }
69 
70 static inline struct attribute * to_attr(struct dentry * dentry)
71 {
72 	struct sysfs_dirent * sd = dentry->d_fsdata;
73 	return ((struct attribute *) sd->s_element);
74 }
75 
76 static inline struct bin_attribute * to_bin_attr(struct dentry * dentry)
77 {
78 	struct sysfs_dirent * sd = dentry->d_fsdata;
79 	return ((struct bin_attribute *) sd->s_element);
80 }
81 
82 static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)
83 {
84 	struct kobject * kobj = NULL;
85 
86 	spin_lock(&dcache_lock);
87 	if (!d_unhashed(dentry)) {
88 		struct sysfs_dirent * sd = dentry->d_fsdata;
89 		if (sd->s_type & SYSFS_KOBJ_LINK) {
90 			struct sysfs_symlink * sl = sd->s_element;
91 			kobj = kobject_get(sl->target_kobj);
92 		} else
93 			kobj = kobject_get(sd->s_element);
94 	}
95 	spin_unlock(&dcache_lock);
96 
97 	return kobj;
98 }
99 
100 static inline void release_sysfs_dirent(struct sysfs_dirent * sd)
101 {
102 	if (sd->s_type & SYSFS_KOBJ_LINK) {
103 		struct sysfs_symlink * sl = sd->s_element;
104 		kfree(sl->link_name);
105 		kobject_put(sl->target_kobj);
106 		kfree(sl);
107 	}
108 	kfree(sd->s_iattr);
109 	kmem_cache_free(sysfs_dir_cachep, sd);
110 }
111 
112 static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
113 {
114 	if (sd) {
115 		WARN_ON(!atomic_read(&sd->s_count));
116 		atomic_inc(&sd->s_count);
117 	}
118 	return sd;
119 }
120 
121 static inline void sysfs_put(struct sysfs_dirent * sd)
122 {
123 	if (atomic_dec_and_test(&sd->s_count))
124 		release_sysfs_dirent(sd);
125 }
126 
127 static inline int sysfs_is_shadowed_inode(struct inode *inode)
128 {
129 	return S_ISDIR(inode->i_mode) && inode->i_op->follow_link;
130 }
131