xref: /openbmc/linux/fs/sysfs/sysfs.h (revision dd14cbc9)
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 	ino_t			s_ino;
9 	struct dentry		* s_dentry;
10 	struct iattr		* s_iattr;
11 	atomic_t		s_event;
12 };
13 
14 extern struct vfsmount * sysfs_mount;
15 extern struct kmem_cache *sysfs_dir_cachep;
16 
17 extern void sysfs_delete_inode(struct inode *inode);
18 extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *);
19 extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *));
20 
21 extern int sysfs_dirent_exist(struct sysfs_dirent *, const unsigned char *);
22 extern int sysfs_make_dirent(struct sysfs_dirent *, struct dentry *, void *,
23 				umode_t, int);
24 
25 extern int sysfs_add_file(struct dentry *, const struct attribute *, int);
26 extern int sysfs_hash_and_remove(struct dentry * dir, const char * name);
27 extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);
28 
29 extern int sysfs_create_subdir(struct kobject *, const char *, struct dentry **);
30 extern void sysfs_remove_subdir(struct dentry *);
31 
32 extern const unsigned char * sysfs_get_name(struct sysfs_dirent *sd);
33 extern void sysfs_drop_dentry(struct sysfs_dirent *sd, struct dentry *parent);
34 extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
35 
36 extern spinlock_t sysfs_lock;
37 extern struct rw_semaphore sysfs_rename_sem;
38 extern struct super_block * sysfs_sb;
39 extern const struct file_operations sysfs_dir_operations;
40 extern const struct file_operations sysfs_file_operations;
41 extern const struct file_operations bin_fops;
42 extern const struct inode_operations sysfs_dir_inode_operations;
43 extern const struct inode_operations sysfs_symlink_inode_operations;
44 
45 struct sysfs_symlink {
46 	char * link_name;
47 	struct kobject * target_kobj;
48 };
49 
50 struct sysfs_buffer {
51 	struct list_head		associates;
52 	size_t				count;
53 	loff_t				pos;
54 	char				* page;
55 	struct sysfs_ops		* ops;
56 	struct semaphore		sem;
57 	int				orphaned;
58 	int				needs_read_fill;
59 	int				event;
60 };
61 
62 struct sysfs_buffer_collection {
63 	struct list_head	associates;
64 };
65 
66 static inline struct kobject * to_kobj(struct dentry * dentry)
67 {
68 	struct sysfs_dirent * sd = dentry->d_fsdata;
69 	return ((struct kobject *) sd->s_element);
70 }
71 
72 static inline struct attribute * to_attr(struct dentry * dentry)
73 {
74 	struct sysfs_dirent * sd = dentry->d_fsdata;
75 	return ((struct attribute *) sd->s_element);
76 }
77 
78 static inline struct bin_attribute * to_bin_attr(struct dentry * dentry)
79 {
80 	struct sysfs_dirent * sd = dentry->d_fsdata;
81 	return ((struct bin_attribute *) sd->s_element);
82 }
83 
84 static inline struct kobject *sysfs_get_kobject(struct dentry *dentry)
85 {
86 	struct kobject * kobj = NULL;
87 
88 	spin_lock(&dcache_lock);
89 	if (!d_unhashed(dentry)) {
90 		struct sysfs_dirent * sd = dentry->d_fsdata;
91 		if (sd->s_type & SYSFS_KOBJ_LINK) {
92 			struct sysfs_symlink * sl = sd->s_element;
93 			kobj = kobject_get(sl->target_kobj);
94 		} else
95 			kobj = kobject_get(sd->s_element);
96 	}
97 	spin_unlock(&dcache_lock);
98 
99 	return kobj;
100 }
101 
102 static inline void release_sysfs_dirent(struct sysfs_dirent * sd)
103 {
104 	if (sd->s_type & SYSFS_KOBJ_LINK) {
105 		struct sysfs_symlink * sl = sd->s_element;
106 		kfree(sl->link_name);
107 		kobject_put(sl->target_kobj);
108 		kfree(sl);
109 	}
110 	kfree(sd->s_iattr);
111 	kmem_cache_free(sysfs_dir_cachep, sd);
112 }
113 
114 static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
115 {
116 	if (sd) {
117 		WARN_ON(!atomic_read(&sd->s_count));
118 		atomic_inc(&sd->s_count);
119 	}
120 	return sd;
121 }
122 
123 static inline void sysfs_put(struct sysfs_dirent * sd)
124 {
125 	if (atomic_dec_and_test(&sd->s_count))
126 		release_sysfs_dirent(sd);
127 }
128 
129 static inline int sysfs_is_shadowed_inode(struct inode *inode)
130 {
131 	return S_ISDIR(inode->i_mode) && inode->i_op->follow_link;
132 }
133