From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: NFS4 crack Date: Mon, 19 Sep 2005 19:59:30 +0100 Message-ID: <20050919185930.GA27874@infradead.org> References: <20050919133921.GA12208@lst.de> <20050919180240.GA26470@infradead.org> <20050919185336.758321BB7B@citi.umich.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Christoph Hellwig , Bryan Henderson , Christoph Hellwig , akpm@osdl.org, "J. Bruce Fields" , linux-fsdevel@vger.kernel.org, neilb@cse.unsw.edu.au Return-path: Received: from pentafluge.infradead.org ([213.146.154.40]:51675 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S932581AbVISS7l (ORCPT ); Mon, 19 Sep 2005 14:59:41 -0400 To: "William A.(Andy) Adamson" Content-Disposition: inline In-Reply-To: <20050919185336.758321BB7B@citi.umich.edu> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Mon, Sep 19, 2005 at 02:53:36PM -0400, William A.(Andy) Adamson wrote: > > They are not nice, but quite a bit different, as we are trying to execute > > them, which can't have bad side-effects in case they don't exist. > > > > What nfsd does is expecting a directory to be present on which it can > > do various operations. That's much worse then trying to execute or > > even read from a file. > > what we could do is not provide a default, and turn off reboot recovery (no > grace period) if the recovery directory is not configured. > > > Besides that all this directory handling really > > belongs into userland as pointed out _three times_ now. > > We were anticipating placing data into files in the recovery directory at each > OPEN and each LOCK call in order to limit the scope of the NFSv4 grace period > to the state that was actually in use prior to the reboot. We therefore went > ahead with a kernel implementation for performance reasons. Then pass in a file descriptor for the each client. Doing all this directory operations is not an option - if you need to do actual file I/O to them that's less of an problem. And please discuss such design issues here on -fsdevel.