Subject: Re: metahook(9)
To: None <wrstuden@netbsd.org>
From: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
List: tech-kern
Date: 06/17/2006 15:32:35
> You also are using identifiers (dev_t and inode_t) that really shouldn't 
> be used outside of the file system. We have cleaned-up abstraction 
> structures (file handles, for example) that remove much of the problem 
> wiht what you're doing. Their existence predates my use of NetBSD, and 
> actually they predate NetBSD. Yet you aren't using them.
> 
> From looking at the man page, I see no reason why metahook(9) won't work 
> with networked file systems. Other than your use of inode number. THAT'S 
> IT! I may be missing something, but you are VERY close to doing it right. 
> Like 10% away or so. Please, just make those small changes, and you will 
> give NetBSD an API that can be very helpful.
> 
> Plus, generation numbers are important, even for local disk stores. Since 
> you aren't storing pointers to the vnodes, use file handles.

while i agree that filehandle is a better abstraction and
is preferable, i'm not sure how it helps "networked file systems".

at least, nfs client can't produce useful fid because nfs filehandles
are likely larger than VFS_MAXFIDSZ.
or, are you talking about introducing a new vfs interface which
can deal with some kind of larger handles?

YAMAMOTO Takashi