From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Wed, 21 May 2008 00:35:46 -0700 (PDT) Received: from cuda.sgi.com ([192.48.176.15]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id m4L7ZeBd026574 for ; Wed, 21 May 2008 00:35:40 -0700 Date: Wed, 21 May 2008 03:36:25 -0400 From: Christoph Hellwig Subject: Re: TAKE 981521 - Return actual name for CI match for dentry cache Message-ID: <20080521073625.GA26580@infradead.org> References: <20080521034449.67F4758C4C29@chook.melbourne.sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080521034449.67F4758C4C29@chook.melbourne.sgi.com> Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: Barry Naujok Cc: sgi.bugs.xfs@engr.sgi.com, xfs@oss.sgi.com On Wed, May 21, 2008 at 01:44:49PM +1000, Barry Naujok wrote: > Return case-insensitive match for dentry cache > > This implements the code to store the actual filename found > during a lookup in the dentry cache and to avoid multiple entries > in the dcache pointing to the same inode. > > To avoid polluting the dcache, we implement a new directory inode > operations for lookup. xfs_vn_ci_lookup() stores the correct case > name in the dcache. > > The "actual name" is only allocated and returned for a case- > insensitive match and not an actual match. > > Another unusual interaction with the dcache is not storing > negative dentries like other filesystems doing a d_add(dentry, NULL) > when an ENOENT is returned. During the VFS lookup, if a dentry > returned has no inode, dput is called and ENOENT is returned. > By not doing a d_add, this actually removes it completely from > the dcache to be reused. create/rename have to be modified to > support unhashed dentries being passed in. This requires the d_add_ci helper which doesn't exist in the CVS on oss.