From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756340Ab2CMPcG (ORCPT ); Tue, 13 Mar 2012 11:32:06 -0400 Received: from mx2.netapp.com ([216.240.18.37]:10150 "EHLO mx2.netapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756094Ab2CMPcD (ORCPT ); Tue, 13 Mar 2012 11:32:03 -0400 X-IronPort-AV: E=Sophos;i="4.73,577,1325491200"; d="scan'208";a="633016435" From: "Myklebust, Trond" To: Miklos Szeredi CC: "viro@ZenIV.linux.org.uk" , "linux-fsdevel@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "hch@infradead.org" , "sfrench@samba.org" , "sage@newdream.net" , "ericvh@gmail.com" Subject: Re: [PATCH 04/25] vfs: add i_op->atomic_open() Thread-Topic: [PATCH 04/25] vfs: add i_op->atomic_open() Thread-Index: AQHNASuUC7lUB3jyj06t8SMxFcM85ZZoz8+A Date: Tue, 13 Mar 2012 15:31:47 +0000 Message-ID: <1331652707.3419.16.camel@lade.trondhjem.org> References: <1331155362-11132-1-git-send-email-miklos@szeredi.hu> <1331155362-11132-5-git-send-email-miklos@szeredi.hu> <1331649485.3419.12.camel@lade.trondhjem.org> <87y5r47cyg.fsf@tucsk.pomaz.szeredi.hu> In-Reply-To: <87y5r47cyg.fsf@tucsk.pomaz.szeredi.hu> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.104.60.115] Content-Type: text/plain; charset="utf-8" Content-ID: <07009DF35449064DBC896DB8964DF189@tahoe.netapp.com> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id q2DFWCvg022131 On Tue, 2012-03-13 at 16:11 +0100, Miklos Szeredi wrote: > "Myklebust, Trond" writes: > > > On Wed, 2012-03-07 at 22:22 +0100, Miklos Szeredi wrote: > >> + > >> + if ((nd->flags & LOOKUP_OPEN) && dir_inode->i_op->atomic_open) { > >> + struct file *filp; > >> + > >> + filp = atomic_open(nd, dentry, op, want_write, &create_error); > >> + if (filp) { > >> + dput(dentry); > >> + return filp; > >> + } > >> + /* fall back to plain lookup */ > >> + } > > > > Would it be possible to allow the filesystem to return a new dentry even > > if it can't complete the actual open? That way we can return the actual > > symlink that caused the open to fail instead of looking it up separately > > (which may be subject to races). > > This should be possible, but I'm reluctant to add more arguments to > ->atomic_open. Other possibilites that come to mind: > > return -ELOOKEDUP - caller should retry d_lookup and proceed with the result > > call opendata_set_dentry(od, dentry) and return NULL - caller checks > opendata for non-NULL dentry and proceeds with that Or convert the existing 'dentry' argument into a struct dentry **. Then again, it might just be easier to convert the existing arguments into a single "open" structure. -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@netapp.com www.netapp.com {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I