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/kobject_ns.h> 13 #include <linux/fs.h> 14 #include <linux/rbtree.h> 15 16 struct sysfs_open_dirent; 17 18 /* type-specific structures for sysfs_dirent->s_* union members */ 19 struct sysfs_elem_dir { 20 struct kobject *kobj; 21 22 unsigned long subdirs; 23 /* children rbtree starts here and goes through sd->s_rb */ 24 struct rb_root children; 25 }; 26 27 struct sysfs_elem_symlink { 28 struct sysfs_dirent *target_sd; 29 }; 30 31 struct sysfs_elem_attr { 32 struct attribute *attr; 33 struct sysfs_open_dirent *open; 34 }; 35 36 struct sysfs_elem_bin_attr { 37 struct bin_attribute *bin_attr; 38 struct hlist_head buffers; 39 }; 40 41 struct sysfs_inode_attrs { 42 struct iattr ia_iattr; 43 void *ia_secdata; 44 u32 ia_secdata_len; 45 }; 46 47 /* 48 * sysfs_dirent - the building block of sysfs hierarchy. Each and 49 * every sysfs node is represented by single sysfs_dirent. 50 * 51 * As long as s_count reference is held, the sysfs_dirent itself is 52 * accessible. Dereferencing s_elem or any other outer entity 53 * requires s_active reference. 54 */ 55 struct sysfs_dirent { 56 atomic_t s_count; 57 atomic_t s_active; 58 #ifdef CONFIG_DEBUG_LOCK_ALLOC 59 struct lockdep_map dep_map; 60 #endif 61 struct sysfs_dirent *s_parent; 62 const char *s_name; 63 64 struct rb_node s_rb; 65 66 union { 67 struct completion *completion; 68 struct sysfs_dirent *removed_list; 69 } u; 70 71 const void *s_ns; /* namespace tag */ 72 unsigned int s_hash; /* ns + name hash */ 73 union { 74 struct sysfs_elem_dir s_dir; 75 struct sysfs_elem_symlink s_symlink; 76 struct sysfs_elem_attr s_attr; 77 struct sysfs_elem_bin_attr s_bin_attr; 78 }; 79 80 unsigned short s_flags; 81 umode_t s_mode; 82 unsigned int s_ino; 83 struct sysfs_inode_attrs *s_iattr; 84 }; 85 86 #define SD_DEACTIVATED_BIAS INT_MIN 87 88 #define SYSFS_TYPE_MASK 0x00ff 89 #define SYSFS_DIR 0x0001 90 #define SYSFS_KOBJ_ATTR 0x0002 91 #define SYSFS_KOBJ_BIN_ATTR 0x0004 92 #define SYSFS_KOBJ_LINK 0x0008 93 #define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK) 94 #define SYSFS_ACTIVE_REF (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR) 95 96 /* identify any namespace tag on sysfs_dirents */ 97 #define SYSFS_NS_TYPE_MASK 0xf00 98 #define SYSFS_NS_TYPE_SHIFT 8 99 100 #define SYSFS_FLAG_MASK ~(SYSFS_NS_TYPE_MASK|SYSFS_TYPE_MASK) 101 #define SYSFS_FLAG_REMOVED 0x02000 102 103 static inline unsigned int sysfs_type(struct sysfs_dirent *sd) 104 { 105 return sd->s_flags & SYSFS_TYPE_MASK; 106 } 107 108 /* 109 * Return any namespace tags on this dirent. 110 * enum kobj_ns_type is defined in linux/kobject.h 111 */ 112 static inline enum kobj_ns_type sysfs_ns_type(struct sysfs_dirent *sd) 113 { 114 return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT; 115 } 116 117 #ifdef CONFIG_DEBUG_LOCK_ALLOC 118 #define sysfs_dirent_init_lockdep(sd) \ 119 do { \ 120 struct attribute *attr = sd->s_attr.attr; \ 121 struct lock_class_key *key = attr->key; \ 122 if (!key) \ 123 key = &attr->skey; \ 124 \ 125 lockdep_init_map(&sd->dep_map, "s_active", key, 0); \ 126 } while (0) 127 #else 128 #define sysfs_dirent_init_lockdep(sd) do {} while (0) 129 #endif 130 131 /* 132 * Context structure to be used while adding/removing nodes. 133 */ 134 struct sysfs_addrm_cxt { 135 struct sysfs_dirent *parent_sd; 136 struct sysfs_dirent *removed; 137 }; 138 139 /* 140 * mount.c 141 */ 142 143 /* 144 * Each sb is associated with a set of namespace tags (i.e. 145 * the network namespace of the task which mounted this sysfs 146 * instance). 147 */ 148 struct sysfs_super_info { 149 void *ns[KOBJ_NS_TYPES]; 150 }; 151 #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info)) 152 extern struct sysfs_dirent sysfs_root; 153 extern struct kmem_cache *sysfs_dir_cachep; 154 155 /* 156 * dir.c 157 */ 158 extern struct mutex sysfs_mutex; 159 extern spinlock_t sysfs_assoc_lock; 160 extern const struct dentry_operations sysfs_dentry_ops; 161 162 extern const struct file_operations sysfs_dir_operations; 163 extern const struct inode_operations sysfs_dir_inode_operations; 164 165 struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd); 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 struct sysfs_dirent *parent_sd); 170 int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 171 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 172 void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 173 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt); 174 175 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, 176 const void *ns, 177 const unsigned char *name); 178 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, 179 const void *ns, 180 const unsigned char *name); 181 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type); 182 183 void release_sysfs_dirent(struct sysfs_dirent *sd); 184 185 int sysfs_create_subdir(struct kobject *kobj, const char *name, 186 struct sysfs_dirent **p_sd); 187 void sysfs_remove_subdir(struct sysfs_dirent *sd); 188 189 int sysfs_rename(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent_sd, 190 const void *ns, const char *new_name); 191 192 static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd) 193 { 194 if (sd) { 195 WARN_ON(!atomic_read(&sd->s_count)); 196 atomic_inc(&sd->s_count); 197 } 198 return sd; 199 } 200 #define sysfs_get(sd) __sysfs_get(sd) 201 202 static inline void __sysfs_put(struct sysfs_dirent *sd) 203 { 204 if (sd && atomic_dec_and_test(&sd->s_count)) 205 release_sysfs_dirent(sd); 206 } 207 #define sysfs_put(sd) __sysfs_put(sd) 208 209 /* 210 * inode.c 211 */ 212 struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd); 213 void sysfs_evict_inode(struct inode *inode); 214 int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr); 215 int sysfs_permission(struct inode *inode, int mask); 216 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); 217 int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, 218 struct kstat *stat); 219 int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, 220 size_t size, int flags); 221 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const void *ns, 222 const char *name); 223 int sysfs_inode_init(void); 224 225 /* 226 * file.c 227 */ 228 extern const struct file_operations sysfs_file_operations; 229 230 int sysfs_add_file(struct sysfs_dirent *dir_sd, 231 const struct attribute *attr, int type); 232 233 int sysfs_add_file_mode(struct sysfs_dirent *dir_sd, 234 const struct attribute *attr, int type, umode_t amode); 235 /* 236 * bin.c 237 */ 238 extern const struct file_operations bin_fops; 239 void unmap_bin_file(struct sysfs_dirent *attr_sd); 240 241 /* 242 * symlink.c 243 */ 244 extern const struct inode_operations sysfs_symlink_inode_operations; 245 int sysfs_create_link_sd(struct sysfs_dirent *sd, struct kobject *target, 246 const char *name); 247