22 use system_error::SystemError;
158     ) -> Result<Arc<dyn FileSystem + 'static>, SystemError> {  in make_ramfs()  argument
169         ) -> Result<Arc<dyn FileSystem + 'static>, SystemError>),
173     fn truncate(&self, len: usize) -> Result<(), SystemError> {  in truncate()  argument
178             return Err(SystemError::EINVAL);  in truncate()
188     fn close(&self, _data: SpinLockGuard<FilePrivateData>) -> Result<(), SystemError> {  in close()  argument
196     ) -> Result<(), SystemError> {  in open()  argument
206     ) -> Result<usize, SystemError> {  in read_at()  argument
208             return Err(SystemError::EINVAL);  in read_at()
215             return Err(SystemError::EISDIR);  in read_at()
223             return Err(SystemError::ENOBUFS);  in read_at()
238     ) -> Result<usize, SystemError> {  in write_at()  argument
240             return Err(SystemError::EINVAL);  in write_at()
248             return Err(SystemError::EISDIR);  in write_at()
271     fn metadata(&self) -> Result<Metadata, SystemError> {  in metadata()  argument
279     fn set_metadata(&self, metadata: &Metadata) -> Result<(), SystemError> {  in set_metadata()  argument
291     fn resize(&self, len: usize) -> Result<(), SystemError> {  in resize()  argument
297             return Err(SystemError::EINVAL);  in resize()
307     ) -> Result<Arc<dyn IndexNode>, SystemError> {  in create_with_data()  argument
313             return Err(SystemError::ENOTDIR);  in create_with_data()
317             return Err(SystemError::EEXIST);  in create_with_data()
356     fn link(&self, name: &str, other: &Arc<dyn IndexNode>) -> Result<(), SystemError> {  in link()  argument
359             .ok_or(SystemError::EPERM)?;  in link()
366             return Err(SystemError::ENOTDIR);  in link()
371             return Err(SystemError::EISDIR);  in link()
376             return Err(SystemError::EEXIST);  in link()
388     fn unlink(&self, name: &str) -> Result<(), SystemError> {  in unlink()  argument
392             return Err(SystemError::ENOTDIR);  in unlink()
396             return Err(SystemError::ENOTEMPTY);  in unlink()
401         let to_delete = inode.children.get(&name).ok_or(SystemError::ENOENT)?;  in unlink()
403             return Err(SystemError::EPERM);  in unlink()
412     fn rmdir(&self, name: &str) -> Result<(), SystemError> {  in rmdir()  argument
417             return Err(SystemError::ENOTDIR);  in rmdir()
420         let to_delete = inode.children.get(&name).ok_or(SystemError::ENOENT)?;  in rmdir()
422             return Err(SystemError::ENOTDIR);  in rmdir()
436     ) -> Result<(), SystemError> {  in move_to()  argument
440             .ok_or(SystemError::EINVAL)?;  in move_to()
462                 .ok_or(SystemError::EINVAL)?,  in move_to()
478     fn find(&self, name: &str) -> Result<Arc<dyn IndexNode>, SystemError> {  in find()  argument
482             return Err(SystemError::ENOTDIR);  in find()
487                 return Ok(inode.self_ref.upgrade().ok_or(SystemError::ENOENT)?);  in find()
491                 return Ok(inode.parent.upgrade().ok_or(SystemError::ENOENT)?);  in find()
499                     .ok_or(SystemError::ENOENT)?  in find()
505     fn get_entry_name(&self, ino: InodeId) -> Result<String, SystemError> {  in get_entry_name()  argument
508             return Err(SystemError::ENOTDIR);  in get_entry_name()
534                     0=>{return Err(SystemError::ENOENT);}  in get_entry_name()
542     fn list(&self) -> Result<Vec<String>, SystemError> {  in list()  argument
545             return Err(SystemError::ENOTDIR);  in list()
569     ) -> Result<Arc<dyn IndexNode>, SystemError> {  in mknod()  argument
572             return Err(SystemError::ENOTDIR);  in mknod()
633     fn dname(&self) -> Result<DName, SystemError> {  in dname()  argument
637     fn parent(&self) -> Result<Arc<dyn IndexNode>, SystemError> {  in parent()  argument
643             .ok_or(SystemError::EINVAL)  in parent()