Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752750AbaBCK3s (ORCPT ); Mon, 3 Feb 2014 05:29:48 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:35659 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752489AbaBCK3q (ORCPT ); Mon, 3 Feb 2014 05:29:46 -0500 Date: Mon, 3 Feb 2014 02:29:43 -0800 From: Christoph Hellwig To: Linus Torvalds Cc: Christoph Hellwig , Ilya Dryomov , Sage Weil , Dave Jones , Linux Kernel Mailing List , ceph-devel@vger.kernel.org, linux-fsdevel , Al Viro , Guangliang Zhao , Li Wang , zheng.z.yan@intel.com Subject: Re: [PATCH v2] ceph: fix posix ACL hooks Message-ID: <20140203102943.GF11829@infradead.org> References: <1391013467-7598-1-git-send-email-ilya.dryomov@inktank.com> <20140130075421.GA10050@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 30, 2014 at 02:01:38PM -0800, Linus Torvalds wrote: > In the end, all the original call-sites should have a dentry, and none > of this is "fundamental". But you're right, it looks like an absolute > nightmare to add the dentry pointer through the whole chain. Damn. > > So I'm not thrilled about it, but maybe that "d_find_alias(inode)" to > find the dentry is good enough in practice. It feels very much > incorrect (it could find a dentry with a path that you cannot actually > access on the server, and result in user-visible errors), but I > definitely see your argument. It may just not be worth the pain for > this odd ceph case. It's not just ceph. 9p fundamentally needs it and I really want to convert 9p to the new code so that we can get rid of the lower level interfaces entirely and eventually move ACL dispatching entirely into the VFS. The same d_find_alias hack should work for 9p as well, although spreading this even more gets uglier and uglier. Similarly for CIFS which pretends to understand the Posix ACL xattrs, but doesn't use any of the infrastructure as it seems to rely on server side enforcement. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/