| 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); |