From owner-cvs-src@FreeBSD.ORG Sat Jun 11 17:04:26 2005 Return-Path: X-Original-To: cvs-src@freebsd.org Delivered-To: cvs-src@freebsd.org Received: from green.homeunix.org (freefall.freebsd.org [216.136.204.21]) by hub.freebsd.org (Postfix) with ESMTP id 3DC9C16A41C; Sat, 11 Jun 2005 17:04:26 +0000 (GMT) (envelope-from green@green.homeunix.org) Received: from green.homeunix.org (green@localhost [127.0.0.1]) by green.homeunix.org (8.13.3/8.13.1) with ESMTP id j5BH4P7Z057345; Sat, 11 Jun 2005 13:04:25 -0400 (EDT) (envelope-from green@green.homeunix.org) Received: (from green@localhost) by green.homeunix.org (8.13.3/8.13.1/Submit) id j5BH4Pwc057344; Sat, 11 Jun 2005 13:04:25 -0400 (EDT) (envelope-from green) Date: Sat, 11 Jun 2005 13:04:25 -0400 From: Brian Fundakowski Feldman To: Alfred Perlstein Message-ID: <20050611170425.GD66188@green.homeunix.org> References: <200506102350.j5ANofFM008212@repoman.freebsd.org> <20050611034930.GY17867@elvis.mu.org> <20050611064956.GC66188@green.homeunix.org> <20050611141021.GD17867@elvis.mu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050611141021.GD17867@elvis.mu.org> User-Agent: Mutt/1.5.6i Cc: cvs-src@freebsd.org, src-committers@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/sys/nfsclient nfs_bio.c nfs_vfsops.c nfsargs.h nfsmount.h src/sys/sys buf.h bufobj.h src/sys/kern vfs_bio.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 11 Jun 2005 17:04:26 -0000 On Sat, Jun 11, 2005 at 07:10:21AM -0700, Alfred Perlstein wrote: > * Brian Fundakowski Feldman [050610 23:49] wrote: > > On Fri, Jun 10, 2005 at 08:49:30PM -0700, Alfred Perlstein wrote: > > > Returning EAGAIN from a disk IO seems bogus, are you sure it makes > > > sense to do that when IO_NDELAY is set? Shouldn't it just be ignored > > > like other FSes do? > > > > Well, it's not disk IO, it's network IO. I figure if you set that > > flag you should expect commensurate error return values. This is > > conceivably a useful behavior, and POSIX does not forbid it, so I just > > made the judgement call to not deny the functionality. > > > > Would you actually be surprised to get EAGAIN if you requested > > non-blocking access to a file stream, ignoring the fact that it just > > happens to not have been done already for other S_ISREG file streams? > > How does one poll(2) or kqueue(2) to determine when EAGAIN will > "go away" ? Maybe I'm misreading the code, but it appears that > O_FSYNC writes on a non-blocking write will _always_ return > EAGAIN? So when is it safe to "AGAIN"? :) Well, the easy solution is just fsync(2) :) This change jibes with Terry's explanation (thanks, Juli). It would be good to implement the rest of the functionality for non-blocking NFS client, too, but I think that can be dne gradually over time. -- Brian Fundakowski Feldman \'[ FreeBSD ]''''''''''\ <> green@FreeBSD.org \ The Power to Serve! \ Opinions expressed are my own. \,,,,,,,,,,,,,,,,,,,,,,\