From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Taber Subject: Re: [autofs] [RFC PATCH]autofs4: hang and proposed fix Date: Wed, 07 Dec 2005 09:52:04 -0500 Message-ID: <4396F714.1010407@us.ibm.com> References: <438F251B.7060602@us.ibm.com> <43906968.6080508@us.ibm.com> <1133547148.8976.25.camel@lade.trondhjem.org> <20051204125612.GA28229@infradead.org> <20051204125740.GB28229@infradead.org> <20051204171729.GA31111@infradead.org> <17302.157.540958.723305@segfault.boston.redhat.com> <20051206214033.GA31000@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: Jeff Moyer , Ian Kent , Trond Myklebust , Ram Pai , autofs mailing list , linux-fsdevel Return-path: Received: from e36.co.us.ibm.com ([32.97.110.154]:48591 "EHLO e36.co.us.ibm.com") by vger.kernel.org with ESMTP id S1750942AbVLGOwL (ORCPT ); Wed, 7 Dec 2005 09:52:11 -0500 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e36.co.us.ibm.com (8.12.11/8.12.11) with ESMTP id jB7EqAfD022799 for ; Wed, 7 Dec 2005 09:52:10 -0500 Received: from d03av03.boulder.ibm.com (d03av03.boulder.ibm.com [9.17.195.169]) by d03relay04.boulder.ibm.com (8.12.10/NCO/VERS6.8) with ESMTP id jB7ErhSn048248 for ; Wed, 7 Dec 2005 07:53:43 -0700 Received: from d03av03.boulder.ibm.com (loopback [127.0.0.1]) by d03av03.boulder.ibm.com (8.12.11/8.13.3) with ESMTP id jB7Eq83P018802 for ; Wed, 7 Dec 2005 07:52:09 -0700 To: Christoph Hellwig In-Reply-To: <20051206214033.GA31000@infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Christoph Hellwig wrote: > To rephrease the above: With current mainline the nameidata argument > is always valid when ->lookup or ->d_revalidate are called except when > the filesystem uses lookup_one_len. lookup_one_len is a helper for fileystem > usage that is only valid to be used on the filesystems own trees. > Is this documented anywhere? How is one to know about this restriction since it isn't obvious from the code? And if this function is only to be used to lookup in ones own filesystem how is a filesystem supposed to lookup a file in another filesystem if they already have a directory dentry in hand? Walking up the dentry tree to recreate a path name so you can call path_walk seems a bit much. Without this capablility how does one write a stackable file system? Will