Received: by 2002:ac0:a5a7:0:0:0:0:0 with SMTP id m36-v6csp2322571imm; Tue, 10 Jul 2018 18:17:20 -0700 (PDT) X-Google-Smtp-Source: AAOMgpdLzU408gIm61GxgxoRd2IqePLx6LKvdB+zOCI/EPN9IIhJrOVj9piYlwgmd8Q2+yJH/PSw X-Received: by 2002:a63:175b:: with SMTP id 27-v6mr21418819pgx.31.1531271840277; Tue, 10 Jul 2018 18:17:20 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1531271840; cv=none; d=google.com; s=arc-20160816; b=KxkaEcZi3im2kJo4RlK3ewBBpdkkphzHkUnTHSYOHdU3N1NDwhHczLbezLRW9/ww46 mPMj5yX+moqQ9PD+Q4eXI7cHWNJBdHBucTWdtO3dPfr9Lc8u8NahI/2LMMBB1NAPSQps cu8GLDP5jKaHVACzON0mgRNEBSFuVClw4NA7pEK1EnOw3zer05Zv6vsI1ZEbghzeZSLr mq36UJAx8ITjDKSjj6oLLz/BqzsS4OeAFqXgiCg5uQlEagQeVFfVeDwiy12Tbm1Se7n2 aj0gSsivtc6iR0KI/C4OlJanAiAMrnaDOHDLrnY3ymMU2ygdbPeCim/msAcV1lQe/FVW r2LA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date:arc-authentication-results; bh=sLCDrdXUrJ5fvvE2YZbYo6aA6TyV0oyygx7iIvEFg8c=; b=a9zKLVfpAy5vBTOECmXUYTrTEmcXJfOA+TvodHiTSCvXsqi2d1LHPvijAywjrrp6iB 0Tg8Is8FYbarKZMSZ44q6BZoTVPr7UXoNu9c/fybInYkXRTiSiOGHRR93k3V9GSN+F8c +szaO8FGjLxacc0Tkc7unalTcrNcTDg64C8xKo8cn+VYOKqDDly5kYOLryIOGBbpbM5n bdtOLahvJN/BPNonAxjNQD2K4+qwLtecdKA0sHThdNodOAx/gS/l588VF7+I/gO2J2Bg nzt1NZPxdJKTpCcbBC6HDF4vW6UNIoZMSFKmNuIKcotp3yYJn9wK/K+OvtvtoWob40M+ cQmA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id 60-v6si18123363ple.65.2018.07.10.18.17.05; Tue, 10 Jul 2018 18:17:20 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732397AbeGKBR4 (ORCPT + 99 others); Tue, 10 Jul 2018 21:17:56 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:44328 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732278AbeGKBR4 (ORCPT ); Tue, 10 Jul 2018 21:17:56 -0400 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.87 #1 (Red Hat Linux)) id 1fd3jn-00024e-3A; Wed, 11 Jul 2018 01:16:11 +0000 Date: Wed, 11 Jul 2018 02:16:11 +0100 From: Al Viro To: Jann Horn Cc: Andy Lutomirski , David Howells , Linux API , linux-fsdevel@vger.kernel.org, Linus Torvalds , kernel list Subject: Re: [PATCH 24/32] vfs: syscall: Add fsopen() to prepare for superblock creation [ver #9] Message-ID: <20180711011610.GM30522@ZenIV.linux.org.uk> References: <153126248868.14533.9751473662727327569.stgit@warthog.procyon.org.uk> <153126264966.14533.3388004240803696769.stgit@warthog.procyon.org.uk> <686E805C-81F3-43D0-A096-50C644C57EE3@amacapital.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 10, 2018 at 06:14:10PM -0700, Jann Horn wrote: > I also love ioctls, so I think you could also use an ioctl to do the > commit? You can do anything (well, almost anything) that you can do in > syscall context in ioctl context, too; and when you already have a > file descriptor of a specific type that you want to perform an > operation on, an ioctl works just fine. Poe's Law in action...