Subject: Re: Making file handles useful outside of NFS
To: Bill Studenmund <wrstuden@nas.nasa.gov>
From: Konrad Schroder <perseant@hitl.washington.edu>
List: tech-kern
Date: 02/25/1999 17:10:07
On Thu, 25 Feb 1999, Bill Studenmund wrote:

> So I propose we split the current vfs_fhtovp VFS call into two calls, one
> to do the export verification, and another to do the filehandle to vnode
> conversion. Any code which calls the current vfs_fhtovp (currently only in
> nfs_subs.c:nfsrv_fhtovp() ) just become a call to VFS_CHKEXP then
> VFS_FHTOVP (assuming no errors).

This is also a (the only remaining?) necessary ingredient in making the
layered filesystems exportable, too: umapfs (or whichever one) can tell
whether it is exported using umap_check_export, and then pass the
VFS_FHTOVP call on to the underlying layer.

(We have something along these lines running on a web server here that
serves an interdepartmental project: it exports the htdocs directory
through different umap layers depending on the department exported to.)

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