aboutsummaryrefslogtreecommitdiffstats
path: root/fs/sysfs/sysfs.h
blob: 6a37f2386a8d6621eb5dcff2de9e5e986b99e167 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
struct sysfs_elem_dir {
	struct kobject		* kobj;
};

struct sysfs_elem_symlink {
	struct sysfs_dirent	* target_sd;
};

struct sysfs_elem_attr {
	struct attribute	* attr;
};

struct sysfs_elem_bin_attr {
	struct bin_attribute	* bin_attr;
};

/*
 * As long as s_count reference is held, the sysfs_dirent itself is
 * accessible.  Dereferencing s_elem or any other outer entity
 * requires s_active reference.
 */
struct sysfs_dirent {
	atomic_t		s_count;
	atomic_t		s_active;
	struct sysfs_dirent	* s_parent;
	struct sysfs_dirent	* s_sibling;
	struct sysfs_dirent	* s_children;
	const char		* s_name;

	union {
		struct sysfs_elem_dir		dir;
		struct sysfs_elem_symlink	symlink;
		struct sysfs_elem_attr		attr;
		struct sysfs_elem_bin_attr	bin_attr;
	}			s_elem;

	unsigned int		s_flags;
	umode_t			s_mode;
	ino_t			s_ino;
	struct dentry		* s_dentry;
	struct iattr		* s_iattr;
	atomic_t		s_event;
};

#define SD_DEACTIVATED_BIAS	INT_MIN

struct sysfs_addrm_cxt {
	struct sysfs_dirent	*parent_sd;
	struct inode		*parent_inode;
	struct sysfs_dirent	*removed;
	int			cnt;
};

extern struct vfsmount * sysfs_mount;
extern struct sysfs_dirent sysfs_root;
extern struct kmem_cache *sysfs_dir_cachep;

extern struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
extern void sysfs_link_sibling(struct sysfs_dirent *sd);
extern void sysfs_unlink_sibling(struct sysfs_dirent *sd);
extern struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd);
extern void sysfs_put_active(struct sysfs_dirent *sd);
extern struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd);
extern void sysfs_put_active_two(struct sysfs_dirent *sd);
extern void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
			      struct sysfs_dirent *parent_sd);
extern void sysfs_add_one(struct sysfs_addrm_cxt *acxt,
			  struct sysfs_dirent *sd);
extern void sysfs_remove_one(struct sysfs_addrm_cxt *acxt,
			     struct sysfs_dirent *sd);
extern int sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);

extern void sysfs_delete_inode(struct inode *inode);
extern void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode);
extern struct inode * sysfs_get_inode(struct sysfs_dirent *sd);
extern void sysfs_instantiate(struct dentry *dentry, struct inode *inode);

extern void release_sysfs_dirent(struct sysfs_dirent * sd);
extern struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
					      const unsigned char *name);
extern struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
					     const unsigned char *name);
extern struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode,
					     int type);

extern int sysfs_add_file(struct sysfs_dirent *dir_sd,
			  const struct attribute *attr, int type);
extern int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
extern struct sysfs_dirent *sysfs_find(struct sysfs_dirent *dir, const char * name);

extern int sysfs_create_subdir(struct kobject *kobj, const char *name,
			       struct sysfs_dirent **p_sd);
extern void sysfs_remove_subdir(struct sysfs_dirent *sd);

extern int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);

extern spinlock_t sysfs_assoc_lock;
extern struct mutex sysfs_mutex;
extern struct super_block * sysfs_sb;
extern const struct file_operations sysfs_dir_operations;
extern const struct file_operations sysfs_file_operations;
extern const struct file_operations bin_fops;
extern const struct inode_operations sysfs_dir_inode_operations;
extern const struct inode_operations sysfs_symlink_inode_operations;

static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
{
	return sd->s_flags & SYSFS_TYPE_MASK;
}

static inline struct sysfs_dirent * sysfs_get(struct sysfs_dirent * sd)
{
	if (sd) {
		WARN_ON(!atomic_read(&sd->s_count));
		atomic_inc(&sd->s_count);
	}
	return sd;
}

static inline void sysfs_put(struct sysfs_dirent * sd)
{
	if (sd && atomic_dec_and_test(&sd->s_count))
		release_sysfs_dirent(sd);
}

static inline int sysfs_is_shadowed_inode(struct inode *inode)
{
	return S_ISDIR(inode->i_mode) && inode->i_op->follow_link;
}