125     ) -> Result<usize, i32> {  in read_at()  argument
127             return Err(-(EINVAL as i32));  in read_at()
134             return Err(-(EISDIR as i32));  in read_at()
142             return Err(-(ENOBUFS as i32));  in read_at()
157     ) -> Result<usize, i32> {  in write_at()  argument
159             return Err(-(EINVAL as i32));  in write_at()
167             return Err(-(EISDIR as i32));  in write_at()
182     fn poll(&self) -> Result<PollStatus, i32> {  in poll()  argument
188             return Err(-(EISDIR as i32));  in poll()
204     fn metadata(&self) -> Result<Metadata, i32> {  in metadata()  argument
212     fn set_metadata(&self, metadata: &Metadata) -> Result<(), i32> {  in set_metadata()  argument
224     fn resize(&self, len: usize) -> Result<(), i32> {  in resize()  argument
230             return Err(-(EINVAL as i32));  in resize()
240     ) -> Result<Arc<dyn IndexNode>, i32> {  in create_with_data()  argument
245             return Err(-(ENOTDIR as i32));  in create_with_data()
249             return Err(-(EEXIST as i32));  in create_with_data()
286     fn link(&self, name: &str, other: &Arc<dyn IndexNode>) -> Result<(), i32> {  in link()  argument
289             .ok_or(-(EPERM as i32))?;  in link()
295             return Err(-(ENOTDIR as i32));  in link()
300             return Err(-(EISDIR as i32));  in link()
305             return Err(-(EEXIST as i32));  in link()
317     fn unlink(&self, name: &str) -> Result<(), i32> {  in unlink()  argument
321             return Err(-(ENOTDIR as i32));  in unlink()
325             return Err(-(ENOTEMPTY as i32));  in unlink()
329         let to_delete = inode.children.get(name).ok_or(-(ENOENT as i32))?;  in unlink()
331             return Err(-(EPERM as i32));  in unlink()
340     fn rmdir(&self, name: &str) -> Result<(), i32> {  in rmdir()  argument
344             return Err(-(ENOTDIR as i32));  in rmdir()
347         let to_delete = inode.children.get(name).ok_or(-(ENOENT as i32))?;  in rmdir()
349             return Err(-(ENOTDIR as i32));  in rmdir()
363     ) -> Result<(), i32> {  in move_()  argument
377     fn find(&self, name: &str) -> Result<Arc<dyn IndexNode>, i32> {  in find()  argument
381             return Err(-(ENOTDIR as i32));  in find()
386                 return Ok(inode.self_ref.upgrade().ok_or(-(ENOENT as i32))?);  in find()
390                 return Ok(inode.parent.upgrade().ok_or(-(ENOENT as i32))?);  in find()
394                 return Ok(inode.children.get(name).ok_or(-(ENOENT as i32))?.clone());  in find()
399     fn get_entry_name(&self, ino: InodeId) -> Result<String, i32> {  in get_entry_name()  argument
402             return Err(-(ENOTDIR as i32));  in get_entry_name()
423                     0=>{return Err(-(ENOENT as i32));}  in get_entry_name()
431     fn list(&self) -> Result<Vec<String>, i32> {  in list()  argument
434             return Err(-(ENOTDIR as i32));  in list()