diff options
| -rw-r--r-- | fs/debugfs/inode.c | 63 | ||||
| -rw-r--r-- | include/linux/debugfs.h | 9 |
2 files changed, 72 insertions, 0 deletions
diff --git a/fs/debugfs/inode.c b/fs/debugfs/inode.c index ec8896b264d..1d533a2ec3a 100644 --- a/fs/debugfs/inode.c +++ b/fs/debugfs/inode.c @@ -368,6 +368,69 @@ void debugfs_remove(struct dentry *dentry) } EXPORT_SYMBOL_GPL(debugfs_remove); +/** + * debugfs_rename - rename a file/directory in the debugfs filesystem + * @old_dir: a pointer to the parent dentry for the renamed object. This + * should be a directory dentry. + * @old_dentry: dentry of an object to be renamed. + * @new_dir: a pointer to the parent dentry where the object should be + * moved. This should be a directory dentry. + * @new_name: a pointer to a string containing the target name. + * + * This function renames a file/directory in debugfs. The target must not + * exist for rename to succeed. + * + * This function will return a pointer to old_dentry (which is updated to + * reflect renaming) if it succeeds. If an error occurs, %NULL will be + * returned. + * + * If debugfs is not enabled in the kernel, the value -%ENODEV will be + * returned. + */ +struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, + struct dentry *new_dir, const char *new_name) +{ + int error; + struct dentry *dentry = NULL, *trap; + const char *old_name; + + trap = lock_rename(new_dir, old_dir); + /* Source or destination directories don't exist? */ + if (!old_dir->d_inode || !new_dir->d_inode) + goto exit; + /* Source does not exist, cyclic rename, or mountpoint? */ + if (!old_dentry->d_inode || old_dentry == trap || + d_mountpoint(old_dentry)) + goto exit; + dentry = lookup_one_len(new_name, new_dir, strlen(new_name)); + /* Lookup failed, cyclic rename or target exists? */ + if (IS_ERR(dentry) || dentry == trap || dentry->d_inode) + goto exit; + + old_name = fsnotify_oldname_init(old_dentry->d_name.name); + + error = simple_rename(old_dir->d_inode, old_dentry, new_dir->d_inode, + dentry); + if (error) { + fsnotify_oldname_free(old_name); + goto exit; + } + d_move(old_dentry, dentry); + fsnotify_move(old_dir->d_inode, new_dir->d_inode, old_name, + old_dentry->d_name.name, S_ISDIR(old_dentry->d_inode->i_mode), + NULL, old_dentry->d_inode); + fsnotify_oldname_free(old_name); + unlock_rename(new_dir, old_dir); + dput(dentry); + return old_dentry; +exit: + if (dentry && !IS_ERR(dentry)) + dput(dentry); + unlock_rename(new_dir, old_dir); + return NULL; +} +EXPORT_SYMBOL_GPL(debugfs_rename); + static decl_subsys(debug, NULL, NULL); static int __init debugfs_init(void) diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h index 5a9c49534d0..104e51e20e1 100644 --- a/include/linux/debugfs.h +++ b/include/linux/debugfs.h @@ -38,6 +38,9 @@ struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, void debugfs_remove(struct dentry *dentry); +struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, + struct dentry *new_dir, const char *new_name); + struct dentry *debugfs_create_u8(const char *name, mode_t mode, struct dentry *parent, u8 *value); struct dentry *debugfs_create_u16(const char *name, mode_t mode, @@ -85,6 +88,12 @@ static inline struct dentry *debugfs_create_symlink(const char *name, static inline void debugfs_remove(struct dentry *dentry) { } +static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, + struct dentry *new_dir, char *new_name) +{ + return ERR_PTR(-ENODEV); +} + static inline struct dentry *debugfs_create_u8(const char *name, mode_t mode, struct dentry *parent, u8 *value) |