From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 26 Jan 2022 09:11:43 -0500 From: "Michael S. Tsirkin" Subject: Re: [PATCH 2/5] Introduce VIRTIO_F_ADMIN_VQ_INDIRECT_DESC/VIRTIO_F_ADMIN_VQ_IN_ORDER Message-ID: <20220126090911-mutt-send-email-mst@kernel.org> References: <20220118014737-mutt-send-email-mst@kernel.org> <15063a94-85ae-fd1a-6ff1-458a039d1def@redhat.com> <56a7bf50-509d-f9d5-df78-858cb1b156c1@redhat.com> <20220125070649-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit To: Parav Pandit Cc: Max Gurtovoy , Jason Wang , "cohuck@redhat.com" , "virtio-dev@lists.oasis-open.org" , Shahaf Shuler , Oren Duer , "stefanha@redhat.com" List-ID: On Wed, Jan 26, 2022 at 01:29:27PM +0000, Parav Pandit wrote: > > > From: Michael S. Tsirkin > > Sent: Tuesday, January 25, 2022 5:39 PM > > > > > > > So you do agree that managing a managed (create/destroy/setup/etc...) > > > will be done using the AQ of the managing device ? > > > > I think Jason asked that the management commands are split from the queue > > itself, such that they can be implemented in more ways down the road. > > Admin commands involved DMA. And also multiple commands can be enqueued to the device. > I don't see any other construct in the spec other than vq that enables driver and device to achieve both. > Hence split the queue from command is very weird for spec to do. VIRTIO_PCI_CAP_SHARED_MEMORY_CFG can do this. > A recent addition like virtio_fs_req didn’t adopt this suggestion. > > If we just want to split so that admin commands can be transported via non admin queue, we should remove below line from spec: > > "The Admin command set defines the commands that may be issued only to the admin virtqueue" sure > And reword it as below, > > The Admin command set defines the commands to manipulate various features/attributes of another device within the same group... > When VIRTIO_F_ADMIN_VQ feature is negotiated, admin commands must be transported through the admin queue. > > Looks ok? I see no problem with that. -- MST