From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4048DC36010 for ; Fri, 4 Apr 2025 15:54:13 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1u0jMg-0007Wk-Vl; Fri, 04 Apr 2025 11:53:55 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u0jMf-0007VS-CK; Fri, 04 Apr 2025 11:53:53 -0400 Received: from ssh.movementarian.org ([139.162.205.133] helo=movementarian.org) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u0jMd-0001VU-Uw; Fri, 04 Apr 2025 11:53:53 -0400 Received: from movement by movementarian.org with local (Exim 4.95) (envelope-from ) id 1u0jMa-006OxY-Rz; Fri, 04 Apr 2025 16:53:48 +0100 Date: Fri, 4 Apr 2025 16:53:48 +0100 From: John Levon To: =?iso-8859-1?Q?C=E9dric?= Le Goater Cc: qemu-devel@nongnu.org, Jason Herne , Thanos Makatos , Halil Pasic , Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= , Eric Farman , Tony Krowiak , Thomas Huth , qemu-s390x@nongnu.org, Matthew Rosato , Paolo Bonzini , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , Stefano Garzarella , Alex Williamson , David Hildenbrand , Peter Xu , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= , "Michael S. Tsirkin" , Jagannathan Raman , John Johnson , Elena Ufimtseva Subject: Re: [PATCH v8 10/28] vfio: add device IO ops vector Message-ID: References: <20250219144858.266455-1-john.levon@nutanix.com> <20250219144858.266455-11-john.levon@nutanix.com> <18613967-0bd5-4a9d-b2d5-37cd179ea0e6@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <18613967-0bd5-4a9d-b2d5-37cd179ea0e6@redhat.com> X-Url: http://www.movementarian.org/ Received-SPF: pass client-ip=139.162.205.133; envelope-from=movement@movementarian.org; helo=movementarian.org X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Fri, Apr 04, 2025 at 04:36:47PM +0200, Cédric Le Goater wrote: > On 2/19/25 15:48, John Levon wrote: > > From: Jagannathan Raman > > > > For vfio-user, device operations such as IRQ handling and region > > read/writes are implemented in userspace over the control socket, not > > ioctl() or read()/write() to the vfio kernel driver; add an ops vector > > to generalize this, and implement vfio_dev_io_ioctl for interacting > > with the kernel vfio driver. > > > > The ops consistently use the "-errno" return style, as the vfio-user > > implementations get their errors from response messages not from the > > kernel; adjust the callers to handle this as necessary. > > Please adjust the callers before introducing the new ops. As in change things like vfio_enable_vectors() to be "return -errno" style as a preparatory change ? I can do that > > +/* > > + * Traditional ioctl() based io > > + */ > > + > > +static int vfio_io_device_feature(VFIODevice *vbasedev, > > + struct vfio_device_feature *feature) > > 'vfio_device' prefix ? vfio_device_io_device_feature. Minor since it's > local to the file. Sure. Actually I don't really like "io" here either, but not sure of a better prefix. "vfio_device_kern" ?? Getting a bit long winded. > Just minor changes. Looks good. I'll pick up all your other naming suggestions too regards john