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 24 struct rb_root inode_tree; 25 struct rb_root name_tree; 26 }; 27 28 struct sysfs_elem_symlink { 29 struct sysfs_dirent *target_sd; 30 }; 31 32 struct sysfs_elem_attr { 33 struct attribute *attr; 34 struct sysfs_open_dirent *open; 35 }; 36 37 struct sysfs_elem_bin_attr { 38 struct bin_attribute *bin_attr; 39 struct hlist_head buffers; 40 }; 41 42 struct sysfs_inode_attrs { 43 struct iattr ia_iattr; 44 void *ia_secdata; 45 u32 ia_secdata_len; 46 }; 47 48 /* 49 * sysfs_dirent - the building block of sysfs hierarchy. Each and 50 * every sysfs node is represented by single sysfs_dirent. 51 * 52 * As long as s_count reference is held, the sysfs_dirent itself is 53 * accessible. Dereferencing s_elem or any other outer entity 54 * requires s_active reference. 55 */ 56 struct sysfs_dirent { 57 atomic_t s_count; 58 atomic_t s_active; 59 #ifdef CONFIG_DEBUG_LOCK_ALLOC 60 struct lockdep_map dep_map; 61 #endif 62 struct sysfs_dirent *s_parent; 63 const char *s_name; 64 65 struct rb_node inode_node; 66 struct rb_node name_node; 67 68 union { 69 struct completion *completion; 70 struct sysfs_dirent *removed_list; 71 } u; 72 73 const void *s_ns; /* namespace tag */ 74 union { 75 struct sysfs_elem_dir s_dir; 76 struct sysfs_elem_symlink s_symlink; 77 struct sysfs_elem_attr s_attr; 78 struct sysfs_elem_bin_attr s_bin_attr; 79 }; 80 81 unsigned int s_flags; 82 unsigned short s_mode; 83 ino_t s_ino; 84 struct sysfs_inode_attrs *s_iattr; 85 }; 86 87 #define SD_DEACTIVATED_BIAS INT_MIN 88 89 #define SYSFS_TYPE_MASK 0x00ff 90 #define SYSFS_DIR 0x0001 91 #define SYSFS_KOBJ_ATTR 0x0002 92 #define SYSFS_KOBJ_BIN_ATTR 0x0004 93 #define SYSFS_KOBJ_LINK 0x0008 94 #define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK) 95 #define SYSFS_ACTIVE_REF (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR) 96 97 /* identify any namespace tag on sysfs_dirents */ 98 #define SYSFS_NS_TYPE_MASK 0xff00 99 #define SYSFS_NS_TYPE_SHIFT 8 100 101 #define SYSFS_FLAG_MASK ~(SYSFS_NS_TYPE_MASK|SYSFS_TYPE_MASK) 102 #define SYSFS_FLAG_REMOVED 0x020000 103 104 static inline unsigned int sysfs_type(struct sysfs_dirent *sd) 105 { 106 return sd->s_flags & SYSFS_TYPE_MASK; 107 } 108 109 /* 110 * Return any namespace tags on this dirent. 111 * enum kobj_ns_type is defined in linux/kobject.h 112 */ 113 static inline enum kobj_ns_type sysfs_ns_type(struct sysfs_dirent *sd) 114 { 115 return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT; 116 } 117 118 #ifdef CONFIG_DEBUG_LOCK_ALLOC 119 #define sysfs_dirent_init_lockdep(sd) \ 120 do { \ 121 struct attribute *attr = sd->s_attr.attr; \ 122 struct lock_class_key *key = attr->key; \ 123 if (!key) \ 124 key = &attr->skey; \ 125 \ 126 lockdep_init_map(&sd->dep_map, "s_active", key, 0); \ 127 } while(0) 128 #else 129 #define sysfs_dirent_init_lockdep(sd) do {} while(0) 130 #endif 131 132 /* 133 * Context structure to be used while adding/removing nodes. 134 */ 135 struct sysfs_addrm_cxt { 136 struct sysfs_dirent *parent_sd; 137 struct sysfs_dirent *removed; 138 }; 139 140 /* 141 * mount.c 142 */ 143 144 /* 145 * Each sb is associated with a set of namespace tags (i.e. 146 * the network namespace of the task which mounted this sysfs 147 * instance). 148 */ 149 struct sysfs_super_info { 150 void *ns[KOBJ_NS_TYPES]; 151 }; 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; 155 156 /* 157 * dir.c 158 */ 159 extern struct mutex sysfs_mutex; 160 extern spinlock_t sysfs_assoc_lock; 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, 190 struct sysfs_dirent *new_parent_sd, 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, struct kstat *stat); 218 int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, 219 size_t size, int flags); 220 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const void *ns, const char *name); 221 int sysfs_inode_init(void); 222 223 /* 224 * file.c 225 */ 226 extern const struct file_operations sysfs_file_operations; 227 228 int sysfs_add_file(struct sysfs_dirent *dir_sd, 229 const struct attribute *attr, int type); 230 231 int sysfs_add_file_mode(struct sysfs_dirent *dir_sd, 232 const struct attribute *attr, int type, mode_t amode); 233 /* 234 * bin.c 235 */ 236 extern const struct file_operations bin_fops; 237 void unmap_bin_file(struct sysfs_dirent *attr_sd); 238 239 /* 240 * symlink.c 241 */ 242 extern const struct inode_operations sysfs_symlink_inode_operations; 243