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#include <linux/lockdep.h>
12#include <linux/fs.h>
13
14struct sysfs_open_dirent;
15
16/* type-specific structures for sysfs_dirent->s_* union members */
17struct sysfs_elem_dir {
18	struct kobject		*kobj;
19	/* children list starts here and goes through sd->s_sibling */
20	struct sysfs_dirent	*children;
21};
22
23struct sysfs_elem_symlink {
24	struct sysfs_dirent	*target_sd;
25};
26
27struct sysfs_elem_attr {
28	struct attribute	*attr;
29	struct sysfs_open_dirent *open;
30};
31
32struct sysfs_elem_bin_attr {
33	struct bin_attribute	*bin_attr;
34	struct hlist_head	buffers;
35};
36
37struct sysfs_inode_attrs {
38	struct iattr	ia_iattr;
39	void		*ia_secdata;
40	u32		ia_secdata_len;
41};
42
43/*
44 * sysfs_dirent - the building block of sysfs hierarchy.  Each and
45 * every sysfs node is represented by single sysfs_dirent.
46 *
47 * As long as s_count reference is held, the sysfs_dirent itself is
48 * accessible.  Dereferencing s_elem or any other outer entity
49 * requires s_active reference.
50 */
51struct sysfs_dirent {
52	atomic_t		s_count;
53	atomic_t		s_active;
54#ifdef CONFIG_DEBUG_LOCK_ALLOC
55	struct lockdep_map	dep_map;
56#endif
57	struct sysfs_dirent	*s_parent;
58	struct sysfs_dirent	*s_sibling;
59	const char		*s_name;
60
61	const void		*s_ns; /* namespace tag */
62	union {
63		struct sysfs_elem_dir		s_dir;
64		struct sysfs_elem_symlink	s_symlink;
65		struct sysfs_elem_attr		s_attr;
66		struct sysfs_elem_bin_attr	s_bin_attr;
67	};
68
69	unsigned int		s_flags;
70	unsigned short		s_mode;
71	ino_t			s_ino;
72	struct sysfs_inode_attrs *s_iattr;
73};
74
75#define SD_DEACTIVATED_BIAS		INT_MIN
76
77#define SYSFS_TYPE_MASK			0x00ff
78#define SYSFS_DIR			0x0001
79#define SYSFS_KOBJ_ATTR			0x0002
80#define SYSFS_KOBJ_BIN_ATTR		0x0004
81#define SYSFS_KOBJ_LINK			0x0008
82#define SYSFS_COPY_NAME			(SYSFS_DIR | SYSFS_KOBJ_LINK)
83#define SYSFS_ACTIVE_REF		(SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR)
84
85/* identify any namespace tag on sysfs_dirents */
86#define SYSFS_NS_TYPE_MASK		0xff00
87#define SYSFS_NS_TYPE_SHIFT		8
88
89#define SYSFS_FLAG_MASK			~(SYSFS_NS_TYPE_MASK|SYSFS_TYPE_MASK)
90#define SYSFS_FLAG_REMOVED		0x020000
91
92static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
93{
94	return sd->s_flags & SYSFS_TYPE_MASK;
95}
96
97/*
98 * Return any namespace tags on this dirent.
99 * enum kobj_ns_type is defined in linux/kobject.h
100 */
101static inline enum kobj_ns_type sysfs_ns_type(struct sysfs_dirent *sd)
102{
103	return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT;
104}
105
106#ifdef CONFIG_DEBUG_LOCK_ALLOC
107#define sysfs_dirent_init_lockdep(sd)				\
108do {								\
109	struct attribute *attr = sd->s_attr.attr;		\
110	struct lock_class_key *key = attr->key;			\
111	if (!key)						\
112		key = &attr->skey;				\
113								\
114	lockdep_init_map(&sd->dep_map, "s_active", key, 0);	\
115} while(0)
116#else
117#define sysfs_dirent_init_lockdep(sd) do {} while(0)
118#endif
119
120/*
121 * Context structure to be used while adding/removing nodes.
122 */
123struct sysfs_addrm_cxt {
124	struct sysfs_dirent	*parent_sd;
125	struct sysfs_dirent	*removed;
126};
127
128/*
129 * mount.c
130 */
131
132/*
133 * Each sb is associated with a set of namespace tags (i.e.
134 * the network namespace of the task which mounted this sysfs
135 * instance).
136 */
137struct sysfs_super_info {
138	const void *ns[KOBJ_NS_TYPES];
139};
140#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
141extern struct sysfs_dirent sysfs_root;
142extern struct kmem_cache *sysfs_dir_cachep;
143
144/*
145 * dir.c
146 */
147extern struct mutex sysfs_mutex;
148extern spinlock_t sysfs_assoc_lock;
149
150extern const struct file_operations sysfs_dir_operations;
151extern const struct inode_operations sysfs_dir_inode_operations;
152
153struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd);
154struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd);
155void sysfs_put_active(struct sysfs_dirent *sd);
156void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt,
157		       struct sysfs_dirent *parent_sd);
158int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
159int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
160void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
161void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
162
163struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
164				       const void *ns,
165				       const unsigned char *name);
166struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
167				      const void *ns,
168				      const unsigned char *name);
169struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type);
170
171void release_sysfs_dirent(struct sysfs_dirent *sd);
172
173int sysfs_create_subdir(struct kobject *kobj, const char *name,
174			struct sysfs_dirent **p_sd);
175void sysfs_remove_subdir(struct sysfs_dirent *sd);
176
177int sysfs_rename(struct sysfs_dirent *sd,
178	struct sysfs_dirent *new_parent_sd, const void *ns, const char *new_name);
179
180static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd)
181{
182	if (sd) {
183		WARN_ON(!atomic_read(&sd->s_count));
184		atomic_inc(&sd->s_count);
185	}
186	return sd;
187}
188#define sysfs_get(sd) __sysfs_get(sd)
189
190static inline void __sysfs_put(struct sysfs_dirent *sd)
191{
192	if (sd && atomic_dec_and_test(&sd->s_count))
193		release_sysfs_dirent(sd);
194}
195#define sysfs_put(sd) __sysfs_put(sd)
196
197/*
198 * inode.c
199 */
200struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd);
201void sysfs_evict_inode(struct inode *inode);
202int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr);
203int sysfs_permission(struct inode *inode, int mask);
204int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
205int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
206int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
207		size_t size, int flags);
208int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const void *ns, const char *name);
209int sysfs_inode_init(void);
210
211/*
212 * file.c
213 */
214extern const struct file_operations sysfs_file_operations;
215
216int sysfs_add_file(struct sysfs_dirent *dir_sd,
217		   const struct attribute *attr, int type);
218
219int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
220			const struct attribute *attr, int type, mode_t amode);
221/*
222 * bin.c
223 */
224extern const struct file_operations bin_fops;
225void unmap_bin_file(struct sysfs_dirent *attr_sd);
226
227/*
228 * symlink.c
229 */
230extern const struct inode_operations sysfs_symlink_inode_operations;
231