From: "J. Bruce Fields" Subject: Re: [PATCH 0/4] [RESEND] 32/64 bit llseek hashes (v5) Date: Wed, 11 Jan 2012 09:48:27 -0500 Message-ID: <20120111144827.GA32381@fieldses.org> References: <20120109132137.2616029.76288.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Theodore Ts'o , linux-nfs@vger.kernel.org, Bernd Schubert , ext4 development , linux-fsdevel Devel , Fan Yong , "J. Bruce Fields" , Eric Sandeen To: Andreas Dilger Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Tue, Jan 10, 2012 at 04:27:15AM -0700, Andreas Dilger wrote: > On 2012-01-09, at 6:21 AM, Bernd Schubert wrote: > > With the ext3/ext4 directory index implementation hashes are used to specify > > offsets for llseek(). For compatibility with NFSv2 and 32-bit user space > > on 64-bit systems (kernel space) ext3/ext4 currently only return 32-bit > > hashes and therefore the probability of hash collisions for larger directories > > is rather high. As recently reported on the NFS mailing list that theoretical > > problem also happens on real systems: > > http://comments.gmane.org/gmane.linux.nfs/40863 > > > > The following series adds two new f_mode flags to tell ext4 > > to use 32-bit or 64-bit hash values for llseek() calls. > > These flags can then used by network file systems, such as NFS, to > > request 32-bit or 64-bit offsets (hashes). > > Ted, it would be great if these patches could land. We hit issues like > this previously as well, which is why we started this patch series in the > first place. Yes, this needs to be fixed--is there anything in particular holding up these patches? --b.