12 use system_error::SystemError;
128     fn mmap(&self, _start: usize, _len: usize, _offset: usize) -> Result<(), SystemError> {  in mmap()  argument
129         return Err(SystemError::ENOSYS);  in mmap()
139     ) -> Result<(), SystemError> {  in open()  argument
141         return Err(SystemError::ENOSYS);  in open()
148     fn close(&self, _data: SpinLockGuard<FilePrivateData>) -> Result<(), SystemError> {  in close()  argument
150         return Err(SystemError::ENOSYS);  in close()
168     ) -> Result<usize, SystemError>;  in read_at()  argument
185     ) -> Result<usize, SystemError>;  in write_at()  argument
190     fn poll(&self, _private_data: &FilePrivateData) -> Result<usize, SystemError> {  in poll()  argument
192         return Err(SystemError::ENOSYS);  in poll()
199     fn metadata(&self) -> Result<Metadata, SystemError> {  in metadata()  argument
201         return Err(SystemError::ENOSYS);  in metadata()
208     fn set_metadata(&self, _metadata: &Metadata) -> Result<(), SystemError> {  in set_metadata()  argument
210         return Err(SystemError::ENOSYS);  in set_metadata()
220     fn resize(&self, _len: usize) -> Result<(), SystemError> {  in resize()  argument
222         return Err(SystemError::ENOSYS);  in resize()
238     ) -> Result<Arc<dyn IndexNode>, SystemError> {  in create()  argument
258     ) -> Result<Arc<dyn IndexNode>, SystemError> {  in create_with_data()  argument
260         return Err(SystemError::ENOSYS);  in create_with_data()
270     fn link(&self, _name: &str, _other: &Arc<dyn IndexNode>) -> Result<(), SystemError> {  in link()  argument
272         return Err(SystemError::ENOSYS);  in link()
281     fn unlink(&self, _name: &str) -> Result<(), SystemError> {  in unlink()  argument
283         return Err(SystemError::ENOSYS);  in unlink()
292     fn rmdir(&self, _name: &str) -> Result<(), SystemError> {  in rmdir()  argument
293         return Err(SystemError::ENOSYS);  in rmdir()
305     ) -> Result<(), SystemError> {  in move_to()  argument
307         return Err(SystemError::ENOSYS);  in move_to()
316     fn find(&self, _name: &str) -> Result<Arc<dyn IndexNode>, SystemError> {  in find()  argument
318         return Err(SystemError::ENOSYS);  in find()
327     fn get_entry_name(&self, _ino: InodeId) -> Result<String, SystemError> {  in get_entry_name()  argument
329         return Err(SystemError::ENOSYS);  in get_entry_name()
338     fn get_entry_name_and_metadata(&self, ino: InodeId) -> Result<(String, Metadata), SystemError> {  in get_entry_name_and_metadata()  argument
357     ) -> Result<usize, SystemError> {  in ioctl()  argument
359         return Err(SystemError::ENOSYS);  in ioctl()
366     ) -> Result<usize, SystemError> {  in kernel_ioctl()  argument
367         return Err(SystemError::ENOSYS);  in kernel_ioctl()
378     fn list(&self) -> Result<Vec<String>, SystemError>;  in list()  argument
404     fn mount(&self, _fs: Arc<dyn FileSystem>) -> Result<Arc<MountFS>, SystemError> {  in mount()  argument
405         return Err(SystemError::ENOSYS);  in mount()
429     fn mount_from(&self, _des: Arc<dyn IndexNode>) -> Result<Arc<MountFS>, SystemError> {  in mount_from()  argument
430         return Err(SystemError::ENOSYS);  in mount_from()
453     fn umount(&self) -> Result<Arc<MountFS>, SystemError> {  in umount()  argument
454         return Err(SystemError::ENOSYS);  in umount()
476     fn absolute_path(&self) -> Result<String, SystemError> {  in absolute_path()  argument
477         return Err(SystemError::ENOSYS);  in absolute_path()
483     fn truncate(&self, _len: usize) -> Result<(), SystemError> {  in truncate()  argument
484         return Err(SystemError::ENOSYS);  in truncate()
488     fn sync(&self) -> Result<(), SystemError> {  in sync()  argument
500     ) -> Result<Arc<dyn IndexNode>, SystemError> {  in mknod()  argument
501         return Err(SystemError::ENOSYS);  in mknod()
519     fn mkdir(&self, name: &str, mode: ModeType) -> Result<Arc<dyn IndexNode>, SystemError> {  in mkdir()  argument
525                     Err(SystemError::EEXIST)  in mkdir()
528             Err(SystemError::ENOENT) => self.create(name, FileType::Dir, mode),  in mkdir()
549     fn dname(&self) -> Result<DName, SystemError> {  in dname()  argument
550         return Err(SystemError::ENOSYS);  in dname()
565     fn parent(&self) -> Result<Arc<dyn IndexNode>, SystemError> {  in parent()  argument
597     pub fn lookup(&self, path: &str) -> Result<Arc<dyn IndexNode>, SystemError> {  in lookup()  argument
605     ) -> Result<Arc<dyn IndexNode>, SystemError> {  in lookup_follow_symlink()  argument
614     ) -> Result<Arc<dyn IndexNode>, SystemError> {  in lookup_follow_symlink2()  argument
638     ) -> Result<Arc<dyn IndexNode>, SystemError> {  in do_lookup_follow_symlink()  argument
640             return Err(SystemError::ENOTDIR);  in do_lookup_follow_symlink()
657                 return Err(SystemError::ENOTDIR);  in do_lookup_follow_symlink()
700                     ::core::str::from_utf8(&content[..len]).map_err(|_| SystemError::EINVAL)?,  in do_lookup_follow_symlink()
941     ) -> Result<Arc<dyn FileSystem>, SystemError> {  in call()  argument
951     fn(data: Option<&dyn FileSystemMakerData>) -> Result<Arc<dyn FileSystem>, SystemError>;
981                 Err(SystemError::EINVAL)