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 14 struct sysfs_open_dirent; 15 16 /* type-specific structures for sysfs_dirent->s_* union members */ 17 struct 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 23 struct sysfs_elem_symlink { 24 struct sysfs_dirent *target_sd; 25 }; 26 27 struct sysfs_elem_attr { 28 struct attribute *attr; 29 struct sysfs_open_dirent *open; 30 }; 31 32 struct sysfs_elem_bin_attr { 33 struct bin_attribute *bin_attr; 34 struct hlist_head buffers; 35 }; 36 37 struct 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 */ 51 struct 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 92 static 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 */ 101 static 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) \ 108 do { \ 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 */ 123 struct 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 */ 137 struct sysfs_super_info { 138 const void *ns[KOBJ_NS_TYPES]; 139 }; 140 #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info)) 141 extern struct sysfs_dirent sysfs_root; 142 extern struct kmem_cache *sysfs_dir_cachep; 143 144 /* 145 * dir.c 146 */ 147 extern struct mutex sysfs_mutex; 148 extern spinlock_t sysfs_assoc_lock; 149 150 extern const struct file_operations sysfs_dir_operations; 151 extern const struct inode_operations sysfs_dir_inode_operations; 152 153 struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd); 154 struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd); 155 void sysfs_put_active(struct sysfs_dirent *sd); 156 void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, 157 struct sysfs_dirent *parent_sd); 158 int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 159 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 160 void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 161 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt); 162 163 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, 164 const void *ns, 165 const unsigned char *name); 166 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, 167 const void *ns, 168 const unsigned char *name); 169 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type); 170 171 void release_sysfs_dirent(struct sysfs_dirent *sd); 172 173 int sysfs_create_subdir(struct kobject *kobj, const char *name, 174 struct sysfs_dirent **p_sd); 175 void sysfs_remove_subdir(struct sysfs_dirent *sd); 176 177 int sysfs_rename(struct sysfs_dirent *sd, 178 struct sysfs_dirent *new_parent_sd, const void *ns, const char *new_name); 179 180 static 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) 189 190 static 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 */ 200 struct inode *sysfs_get_inode(struct super_block *sb, struct sysfs_dirent *sd); 201 void sysfs_evict_inode(struct inode *inode); 202 int sysfs_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr); 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, struct kstat *stat); 206 int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, 207 size_t size, int flags); 208 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const void *ns, const char *name); 209 int sysfs_inode_init(void); 210 211 /* 212 * file.c 213 */ 214 extern const struct file_operations sysfs_file_operations; 215 216 int sysfs_add_file(struct sysfs_dirent *dir_sd, 217 const struct attribute *attr, int type); 218 219 int sysfs_add_file_mode(struct sysfs_dirent *dir_sd, 220 const struct attribute *attr, int type, mode_t amode); 221 /* 222 * bin.c 223 */ 224 extern const struct file_operations bin_fops; 225 void unmap_bin_file(struct sysfs_dirent *attr_sd); 226 227 /* 228 * symlink.c 229 */ 230 extern const struct inode_operations sysfs_symlink_inode_operations; 231