2 * fs/sysfs/sysfs.h - sysfs internal header file
4 * Copyright (c) 2001-3 Patrick Mochel
5 * Copyright (c) 2007 SUSE Linux Products GmbH
6 * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
8 * This file is released under the GPLv2.
11 #include <linux/lockdep.h>
12 #include <linux/kobject_ns.h>
14 #include <linux/rbtree.h>
16 struct sysfs_open_dirent;
18 /* type-specific structures for sysfs_dirent->s_* union members */
19 struct sysfs_elem_dir {
20 unsigned long subdirs;
21 /* children rbtree starts here and goes through sd->s_rb */
22 struct rb_root children;
25 struct sysfs_elem_symlink {
26 struct sysfs_dirent *target_sd;
29 struct sysfs_elem_attr {
30 const struct kernfs_ops *ops;
31 struct sysfs_open_dirent *open;
35 struct sysfs_inode_attrs {
36 struct iattr ia_iattr;
42 * sysfs_dirent - the building block of sysfs hierarchy. Each and
43 * every sysfs node is represented by single sysfs_dirent.
45 * As long as s_count reference is held, the sysfs_dirent itself is
46 * accessible. Dereferencing s_elem or any other outer entity
47 * requires s_active reference.
52 #ifdef CONFIG_DEBUG_LOCK_ALLOC
53 struct lockdep_map dep_map;
55 struct sysfs_dirent *s_parent;
61 struct completion *completion;
62 struct sysfs_dirent *removed_list;
65 const void *s_ns; /* namespace tag */
66 unsigned int s_hash; /* ns + name hash */
68 struct sysfs_elem_dir s_dir;
69 struct sysfs_elem_symlink s_symlink;
70 struct sysfs_elem_attr s_attr;
75 unsigned short s_flags;
78 struct sysfs_inode_attrs *s_iattr;
81 #define SD_DEACTIVATED_BIAS INT_MIN
83 #define SYSFS_TYPE_MASK 0x00ff
84 #define SYSFS_DIR 0x0001
85 #define SYSFS_KOBJ_ATTR 0x0002
86 #define SYSFS_KOBJ_LINK 0x0008
87 #define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK)
88 #define SYSFS_ACTIVE_REF SYSFS_KOBJ_ATTR
90 #define SYSFS_FLAG_MASK ~SYSFS_TYPE_MASK
91 #define SYSFS_FLAG_NS 0x01000
92 #define SYSFS_FLAG_REMOVED 0x02000
93 #define SYSFS_FLAG_HAS_SEQ_SHOW 0x04000
94 #define SYSFS_FLAG_HAS_MMAP 0x08000
96 static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
98 return sd->s_flags & SYSFS_TYPE_MASK;
101 #ifdef CONFIG_DEBUG_LOCK_ALLOC
103 #define sysfs_dirent_init_lockdep(sd) \
105 struct attribute *attr = sd->priv; \
106 struct lock_class_key *key = attr->key; \
110 lockdep_init_map(&sd->dep_map, "s_active", key, 0); \
113 /* Test for attributes that want to ignore lockdep for read-locking */
114 static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
116 struct attribute *attr = sd->priv;
118 return sysfs_type(sd) == SYSFS_KOBJ_ATTR && attr->ignore_lockdep;
123 #define sysfs_dirent_init_lockdep(sd) do {} while (0)
125 static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
133 * Context structure to be used while adding/removing nodes.
135 struct sysfs_addrm_cxt {
136 struct sysfs_dirent *removed;
144 * Each sb is associated with one namespace tag, currently the network
145 * namespace of the task which mounted this sysfs instance. If multiple
146 * tags become necessary, make the following an array and compare
147 * sysfs_dirent tag against every entry.
149 struct sysfs_super_info {
152 #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
153 extern struct sysfs_dirent sysfs_root;
154 extern struct kmem_cache *sysfs_dir_cachep;
159 extern struct mutex sysfs_mutex;
160 extern spinlock_t sysfs_symlink_target_lock;
161 extern const struct dentry_operations sysfs_dentry_ops;
163 extern const struct file_operations sysfs_dir_operations;
164 extern const struct inode_operations sysfs_dir_inode_operations;
166 struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd);
167 void sysfs_put_active(struct sysfs_dirent *sd);
168 void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt);
169 void sysfs_warn_dup(struct sysfs_dirent *parent, const char *name);
170 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd,
171 struct sysfs_dirent *parent_sd);
172 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
174 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
175 const unsigned char *name,
177 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type);
179 void release_sysfs_dirent(struct sysfs_dirent *sd);
181 static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd)
184 WARN_ON(!atomic_read(&sd->s_count));
185 atomic_inc(&sd->s_count);
189 #define sysfs_get(sd) __sysfs_get(sd)
191 static inline void __sysfs_put(struct sysfs_dirent *sd)
193 if (sd && atomic_dec_and_test(&sd->s_count))
194 release_sysfs_dirent(sd);
196 #define sysfs_put(sd) __sysfs_put(sd)
201 struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd);
202 void sysfs_evict_inode(struct inode *inode);
203 int sysfs_permission(struct inode *inode, int mask);
204 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
205 int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
207 int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
208 size_t size, int flags);
209 int sysfs_inode_init(void);
214 extern const struct file_operations kernfs_file_operations;
216 int sysfs_add_file(struct sysfs_dirent *dir_sd,
217 const struct attribute *attr, bool is_bin);
219 int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
220 const struct attribute *attr, bool is_bin,
221 umode_t amode, const void *ns);
222 void sysfs_unmap_bin_file(struct sysfs_dirent *sd);
227 extern const struct inode_operations sysfs_symlink_inode_operations;
228 int sysfs_create_link_sd(struct sysfs_dirent *sd, struct kobject *target,