From: Chuck Lever Subject: Re: [PATCH 2/2] Enable v4 mounts when either "nfsvers=4" or "vers=4" option are set (vers-02) Date: Wed, 26 Aug 2009 13:22:30 -0400 Message-ID: References: <4A9424DB.2040303@RedHat.com> <4A942593.8030101@RedHat.com> <4A943914.9020104@RedHat.com> <7AB7BC01-F9E5-4611-BB4B-2B6E27069631@oracle.com> <4A944645.1020003@RedHat.com> <1251233345.25372.67.camel@heimdal.trondhjem.org> <4A954FBF.3030606@RedHat.com> <23199F1A-EA23-4DE1-AAB8-92D4B508C865@oracle.com> <4A956BF2.6000902@RedHat.com> Mime-Version: 1.0 (Apple Message framework v936) Content-Type: text/plain; charset="us-ascii"; Format="flowed"; DelSp="yes" Cc: Linux NFS Mailing list , Linux NFSv4 mailing list To: Steve Dickson Return-path: In-Reply-To: <4A956BF2.6000902@RedHat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: nfsv4-bounces@linux-nfs.org Errors-To: nfsv4-bounces@linux-nfs.org List-ID: On Aug 26, 2009, at 1:08 PM, Steve Dickson wrote: > On 08/26/2009 12:35 PM, Chuck Lever wrote: >> On Aug 26, 2009, at 11:07 AM, Steve Dickson wrote: >>>> I think that would be a much better approach. If nfs4 goes away >>>> someday, for example, it will be completely transparent to the >>>> mount >>>> command if we've already pushed "-t nfs, vers=4" conversion into >>>> the >>>> kernel. >>> Well when/if that day comes, we can easily pull the patches from the >>> mount >>> command. >> >> You know it's never that easy. The mount command has to keep legacy >> logic for older kernels. I'm just saying that the less the mount >> command has to worry about what kernel version is running, the >> cleaner >> the mount command will be. > Well with this patch, since we are only concentrating on text mounts, > we are already breaking with the tradition of keeping legacy logic... > And again as long as the nfs4 file system exists this approach will > work... > >> >>>> We are pushing all of the details of NFS mounting into the kernel >>>> anyway, over time. >>> Which I've never been a fan of... Again it's much easier change user >>> level code (and more people can do it) than kernel code... >>> especially >>> with things of this nature... >> >> People can continue to change the mount command all they want. In >> fact >> the user space text-based option parsing code is pretty darn >> flexible as >> it is now. > Yes... the user space parsing code is very well written... > >> >> I don't think we're denying that your proposal is expedient. The >> question I think is where we want to be in the long run, > NFS v4 as the default protocol version followed by NFS V4.1 becoming > the > default protocol version. > >> and if your proposed method to handle -t nfs -o vers=4 will make >> it more complicated to get there. > No. I'm proposing a simple shorthand patch that will make mounting > nfs4 > file systems easier in hope of moving the technology forward by making > it more accessible... What I believe you are proposing is architecture > change to hide the fact nfs and nfs4 are separate file systems... Nope, we're proposing doing the simple method in the kernel instead of in the mount command. > But in the end, if we do the simple shorthand patch (making the > technology > available today) or the major architecture change (making the > technology > available the distant future) with both approaches 'mount -o v4' > will do the exact same thing... > > I for moving the technology today... > > steved. > > > -- Chuck Lever chuck[dot]lever[at]oracle[dot]com