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 15 struct sysfs_open_dirent; 16 17 /* type-specific structures for sysfs_dirent->s_* union members */ 18 struct sysfs_elem_dir { 19 struct kobject *kobj; 20 /* children list starts here and goes through sd->s_sibling */ 21 struct sysfs_dirent *children; 22 }; 23 24 struct sysfs_elem_symlink { 25 struct sysfs_dirent *target_sd; 26 }; 27 28 struct sysfs_elem_attr { 29 struct attribute *attr; 30 struct sysfs_open_dirent *open; 31 }; 32 33 struct sysfs_elem_bin_attr { 34 struct bin_attribute *bin_attr; 35 struct hlist_head buffers; 36 }; 37 38 struct sysfs_inode_attrs { 39 struct iattr ia_iattr; 40 void *ia_secdata; 41 u32 ia_secdata_len; 42 }; 43 44 /* 45 * sysfs_dirent - the building block of sysfs hierarchy. Each and 46 * every sysfs node is represented by single sysfs_dirent. 47 * 48 * As long as s_count reference is held, the sysfs_dirent itself is 49 * accessible. Dereferencing s_elem or any other outer entity 50 * requires s_active reference. 51 */ 52 struct sysfs_dirent { 53 atomic_t s_count; 54 atomic_t s_active; 55 #ifdef CONFIG_DEBUG_LOCK_ALLOC 56 struct lockdep_map dep_map; 57 #endif 58 struct sysfs_dirent *s_parent; 59 struct sysfs_dirent *s_sibling; 60 const char *s_name; 61 62 const void *s_ns; /* namespace tag */ 63 union { 64 struct sysfs_elem_dir s_dir; 65 struct sysfs_elem_symlink s_symlink; 66 struct sysfs_elem_attr s_attr; 67 struct sysfs_elem_bin_attr s_bin_attr; 68 }; 69 70 unsigned int s_flags; 71 unsigned short s_mode; 72 ino_t s_ino; 73 struct sysfs_inode_attrs *s_iattr; 74 }; 75 76 #define SD_DEACTIVATED_BIAS INT_MIN 77 78 #define SYSFS_TYPE_MASK 0x00ff 79 #define SYSFS_DIR 0x0001 80 #define SYSFS_KOBJ_ATTR 0x0002 81 #define SYSFS_KOBJ_BIN_ATTR 0x0004 82 #define SYSFS_KOBJ_LINK 0x0008 83 #define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK) 84 #define SYSFS_ACTIVE_REF (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR) 85 86 /* identify any namespace tag on sysfs_dirents */ 87 #define SYSFS_NS_TYPE_MASK 0xff00 88 #define SYSFS_NS_TYPE_SHIFT 8 89 90 #define SYSFS_FLAG_MASK ~(SYSFS_NS_TYPE_MASK|SYSFS_TYPE_MASK) 91 #define SYSFS_FLAG_REMOVED 0x020000 92 93 static inline unsigned int sysfs_type(struct sysfs_dirent *sd) 94 { 95 return sd->s_flags & SYSFS_TYPE_MASK; 96 } 97 98 /* 99 * Return any namespace tags on this dirent. 100 * enum kobj_ns_type is defined in linux/kobject.h 101 */ 102 static inline enum kobj_ns_type sysfs_ns_type(struct sysfs_dirent *sd) 103 { 104 return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT; 105 } 106 107 #ifdef CONFIG_DEBUG_LOCK_ALLOC 108 #define sysfs_dirent_init_lockdep(sd) \ 109 do { \ 110 struct attribute *attr = sd->s_attr.attr; \ 111 struct lock_class_key *key = attr->key; \ 112 if (!key) \ 113 key = &attr->skey; \ 114 \ 115 lockdep_init_map(&sd->dep_map, "s_active", key, 0); \ 116 } while(0) 117 #else 118 #define sysfs_dirent_init_lockdep(sd) do {} while(0) 119 #endif 120 121 /* 122 * Context structure to be used while adding/removing nodes. 123 */ 124 struct sysfs_addrm_cxt { 125 struct sysfs_dirent *parent_sd; 126 struct sysfs_dirent *removed; 127 }; 128 129 /* 130 * mount.c 131 */ 132 133 /* 134 * Each sb is associated with a set of namespace tags (i.e. 135 * the network namespace of the task which mounted this sysfs 136 * instance). 137 */ 138 struct sysfs_super_info { 139 const void *ns[KOBJ_NS_TYPES]; 140 }; 141 #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info)) 142 extern struct sysfs_dirent sysfs_root; 143 extern struct kmem_cache *sysfs_dir_cachep; 144 145 /* 146 * dir.c 147 */ 148 extern struct mutex sysfs_mutex; 149 extern spinlock_t sysfs_assoc_lock; 150 151 extern const struct file_operations sysfs_dir_operations; 152 extern const struct inode_operations sysfs_dir_inode_operations; 153 154 struct dentry *sysfs_get_dentry(struct sysfs_dirent *sd); 155 struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd); 156 void sysfs_put_active(struct sysfs_dirent *sd); 157 void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt, 158 struct sysfs_dirent *parent_sd); 159 int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 160 int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 161 void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd); 162 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt); 163 164 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, 165 const void *ns, 166 const unsigned char *name); 167 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, 168 const void *ns, 169 const unsigned char *name); 170 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type); 171 172 void release_sysfs_dirent(struct sysfs_dirent *sd); 173 174 int sysfs_create_subdir(struct kobject *kobj, const char *name, 175 struct sysfs_dirent **p_sd); 176 void sysfs_remove_subdir(struct sysfs_dirent *sd); 177 178 int sysfs_rename(struct sysfs_dirent *sd, 179 struct sysfs_dirent *new_parent_sd, const void *ns, const char *new_name); 180 181 static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd) 182 { 183 if (sd) { 184 WARN_ON(!atomic_read(&sd->s_count)); 185 atomic_inc(&sd->s_count); 186 } 187 return sd; 188 } 189 #define sysfs_get(sd) __sysfs_get(sd) 190 191 static inline void __sysfs_put(struct sysfs_dirent *sd) 192 { 193 if (sd && atomic_dec_and_test(&sd->s_count)) 194 release_sysfs_dirent(sd); 195 } 196 #define sysfs_put(sd) __sysfs_put(sd) 197 198 /* 199 * inode.c 200 */ 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_sd_setattr(struct sysfs_dirent *sd, struct iattr *iattr); 204 int sysfs_permission(struct inode *inode, int mask, unsigned int flags); 205 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr); 206 int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat); 207 int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value, 208 size_t size, int flags); 209 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const void *ns, const char *name); 210 int sysfs_inode_init(void); 211 212 /* 213 * file.c 214 */ 215 extern const struct file_operations sysfs_file_operations; 216 217 int sysfs_add_file(struct sysfs_dirent *dir_sd, 218 const struct attribute *attr, int type); 219 220 int sysfs_add_file_mode(struct sysfs_dirent *dir_sd, 221 const struct attribute *attr, int type, mode_t amode); 222 /* 223 * bin.c 224 */ 225 extern const struct file_operations bin_fops; 226 void unmap_bin_file(struct sysfs_dirent *attr_sd); 227 228 /* 229 * symlink.c 230 */ 231 extern const struct inode_operations sysfs_symlink_inode_operations; 232