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 ws5-mx01.kavi.com (ws5-mx01.kavi.com [34.193.7.191]) (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 7D4A4EB64DD for ; Thu, 6 Jul 2023 18:48:20 +0000 (UTC) Received: from lists.oasis-open.org (oasis.ws5.connectedcommunity.org [10.110.1.242]) by ws5-mx01.kavi.com (Postfix) with ESMTP id 71DEA2B001 for ; Thu, 6 Jul 2023 18:48:19 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 5C766986812 for ; Thu, 6 Jul 2023 18:48:19 +0000 (UTC) Received: from host09.ws5.connectedcommunity.org (host09.ws5.connectedcommunity.org [10.110.1.97]) by lists.oasis-open.org (Postfix) with QMQP id 4EA8E9867F9; Thu, 6 Jul 2023 18:48:19 +0000 (UTC) Mailing-List: contact virtio-dev-help@lists.oasis-open.org; run by ezmlm List-ID: Sender: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 3999B9867B6 for ; Thu, 6 Jul 2023 18:48:19 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-MC-Unique: lhBORcQhOlGmbcbuEDx_5A-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1688669294; x=1691261294; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=zjfjZVWSlngd4gtvSlwlXKF7D4wZoY5p32iW6lqxKmU=; b=leQP5g8JFpkzGE2kI/ClnssscR8XKJXGo5AxuIMv02aWNe3H0DfZcoO/rWuBpJGFzC b6VVY90tm8nczibBPWZwbXEnNPGTG5tg4rUCygwajA2Kr+CqjwagbHE15+gWO880T2wA awTVG4dU6D8mEMBob0rG4DczNm/Mya/3q81wrRi2bmzxZJTr6ygmAb48jptbBlFkIZ+q qcm7iKQEYWNuYwDE1y8fkkT3041k5AgsNENZOu3gwfSMrBB38Wt138xeKz0a96xQv+JT RcJ80hqiAAgNDaiyxd0H/nj2ScwkObi6TO90UdkbOUU+Skw7EktZfSvYFYSMs9ZtAFU9 eQ3A== X-Gm-Message-State: ABy/qLYbsa+TDuxv0kv8IEesbsR6R02XwnIiBPfZKGpXfcMsoYpEOWlz 2GJTFtaXkw/EFMzIUJUSWpLQTroqzzEPNNdyS80emvkfeVz6AG5J5Nzv6AQx+t+rw4DQ2kIi4Pp I6V2t1Tp6nTDrETxqaOvyYzT/SUDK X-Received: by 2002:a05:600c:2146:b0:3fb:ef6f:9231 with SMTP id v6-20020a05600c214600b003fbef6f9231mr2194923wml.11.1688669294538; Thu, 06 Jul 2023 11:48:14 -0700 (PDT) X-Google-Smtp-Source: APBJJlFNn8TGpim/xVY30phY+7wtLU1t35cMbnWE/KzQ6TScTX1qRo6Xg0SSs4XjRnPOQCvNgJvB3Q== X-Received: by 2002:a05:600c:2146:b0:3fb:ef6f:9231 with SMTP id v6-20020a05600c214600b003fbef6f9231mr2194903wml.11.1688669294225; Thu, 06 Jul 2023 11:48:14 -0700 (PDT) Date: Thu, 6 Jul 2023 14:48:10 -0400 From: "Michael S. Tsirkin" To: Parav Pandit Cc: Cornelia Huck , "virtio-comment@lists.oasis-open.org" , "david.edmondson@oracle.com" , "virtio-dev@lists.oasis-open.org" , "sburla@marvell.com" , "jasowang@redhat.com" , Yishai Hadas , Maor Gottlieb , Shahaf Shuler Message-ID: <20230706144427-mutt-send-email-mst@kernel.org> References: <20230706041714.65600-1-parav@nvidia.com> <20230706041714.65600-5-parav@nvidia.com> <87r0pluhqy.fsf@redhat.com> <20230706123954-mutt-send-email-mst@kernel.org> <20230706132638-mutt-send-email-mst@kernel.org> <20230706135858-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [virtio-dev] Re: [PATCH v10 4/4] transport-pci: Introduce group legacy group member config region access On Thu, Jul 06, 2023 at 06:16:10PM +0000, Parav Pandit wrote: > > > From: Michael S. Tsirkin > > Sent: Thursday, July 6, 2023 2:06 PM > > > > But again even if you add it there, you can not claim it's exactly the same as > > legacy because the address is different, the address type is different, the driver > > is different (this is owner driver) and even the device is different. > > > You drafted below, that I included, > > The driver of the owner device can send a driver notification to the member > device by executing VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE with the > \field{offset} matching \field{Queue Notify} and the \field{data} containing > the virtqueue index to be notified. > > We extend this further by saying Queue notify notifications is sent via MMIO as, > > The driver of the owner device can send a driver notification to the member > device by executing VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE with the > \field{offset} matching \field{Queue Notify} and the \field{data} containing > the virtqueue index to be notified or by performing memory or I/O write in split to two sentences please. E.g. Alternatively, the driver ... > the any of the notification region at offset 0 supplied by the device in the any is agrammatical > VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO result. > > > Please also call out the unusual configuration where the type is "member" and > > then you have the owner driver access the memory of the member device. > > People might be confused. > > > > I also think we should explain that order of entries is a hint to driver: use the 1st > > entry that you can. > > Driver really can choose any valid entry out of the 4 that driver likes. > I really don't see a need for overwriting this area as I fail to see why one will expose multiple entries from the device side in reality. I do: one for owner one for member. which is best for device is device specific. I don't know what do you mean by "overwriting". Explaining in detail? You feel like this because you spent a lot of time thinking about the area and there is a specific solution is very clear in your head. First readers are not like this and second they might have a different solution. -- MST --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org