From: Eric Sandeen Subject: Re: [PATCH 5 2/4] Return 32/64-bit dir name hash according to usage type Date: Fri, 20 Apr 2012 15:04:43 -0500 Message-ID: <4F91C15B.6070200@redhat.com> References: <20120109132137.2616029.76288.stgit@localhost.localdomain> <20120109132148.2616029.68798.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Fan Yong , bfields-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Andreas Dilger To: Bernd Schubert Return-path: In-Reply-To: <20120109132148.2616029.68798.stgit-bi+AKbBUZKY6gyzm1THtWbp2dZbC/Bob@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-ext4.vger.kernel.org On 1/9/12 7:21 AM, Bernd Schubert wrote: > From: Fan Yong > > Traditionally ext2/3/4 has returned a 32-bit hash value from llseek() > to appease NFSv2, which can only handle a 32-bit cookie for seekdir() > and telldir(). However, this causes problems if there are 32-bit hash > collisions, since the NFSv2 server can get stuck resending the same > entries from the directory repeatedly. > > Allow ext4 to return a full 64-bit hash (both major and minor) for > telldir to decrease the chance of hash collisions. This still needs > integration on the NFS side. > > Patch-updated-by: Bernd Schubert > (blame me if something is not correct) Bernd, I've merged this to ext3. Bruce thought maybe you were working on the same. Should I send mine? Also... > +/* > + * ext4_dir_llseek() based on generic_file_llseek() to handle both > + * non-htree and htree directories, where the "offset" is in terms > + * of the filename hash value instead of the byte offset. > + * > + * NOTE: offsets obtained *before* ext4_set_inode_flag(dir, EXT4_INODE_INDEX) > + * will be invalid once the directory was converted into a dx directory > + */ > +loff_t ext4_dir_llseek(struct file *file, loff_t offset, int origin) ext4_llseek() worries about max offset for direct/indirect vs. extent-mapped files. Do we need to worry about the same thing in this function? -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html