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 2A17EC6FA8E for ; Thu, 2 Mar 2023 20:10:26 +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 5CABE77ED for ; Thu, 2 Mar 2023 20:10:25 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 413BB9866AC for ; Thu, 2 Mar 2023 20:10:25 +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 2E2FC984091; Thu, 2 Mar 2023 20:10:25 +0000 (UTC) Mailing-List: contact virtio-dev-help@lists.oasis-open.org; run by ezmlm List-Id: 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 16F099866AF for ; Thu, 2 Mar 2023 20:10:25 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-MC-Unique: 1LIF23G4MU6sL3LtONnEIg-1 Date: Thu, 2 Mar 2023 15:10:11 -0500 From: Stefan Hajnoczi To: "Michael S. Tsirkin" Cc: virtio-comment@lists.oasis-open.org, virtio-dev@lists.oasis-open.org, jasowang@redhat.com, cohuck@redhat.com, sgarzare@redhat.com, nrupal.jani@intel.com, Piotr.Uminski@intel.com, hang.yuan@intel.com, virtio@lists.oasis-open.org, Zhu Lingshan , pasic@linux.ibm.com, Shahaf Shuler , Parav Pandit , Max Gurtovoy Message-ID: <20230302201011.GB2554028@fedora> References: <910b3607a5f255134d30b3e1233e564f564eafb8.1677761896.git.mst@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="O8EmZxQ0wM/KxSAO" Content-Disposition: inline In-Reply-To: <910b3607a5f255134d30b3e1233e564f564eafb8.1677761896.git.mst@redhat.com> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Subject: [virtio-dev] Re: [PATCH v10 03/10] admin: introduce group administration commands --O8EmZxQ0wM/KxSAO Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Mar 02, 2023 at 08:05:02AM -0500, Michael S. Tsirkin wrote: > This introduces a general structure for group administration commands, > used to control device groups through their owner. >=20 > Following patches will introduce specific commands and an interface for > submitting these commands to the owner. >=20 > Signed-off-by: Max Gurtovoy > Signed-off-by: Michael S. Tsirkin > --- > admin.tex | 108 +++++++++++++++++++++++++++++++++++++++++++++++ > introduction.tex | 3 ++ > 2 files changed, 111 insertions(+) >=20 > diff --git a/admin.tex b/admin.tex > index 3dc47be..7e28b77 100644 > --- a/admin.tex > +++ b/admin.tex > @@ -46,4 +46,112 @@ \section{Device groups}\label{sec:Basic Facilities of= a Virtio Device / Device g > PCI transport (see \ref{sec:Virtio Transport Options / Virtio Over PCI B= us}). > \end{description} > =20 > +\subsection{Group administration commands}\label{sec:Basic Facilities of= a Virtio Device / Device groups / Group administration commands} > =20 > +The driver sends group administration commands to the owner device of I notice that the terminology is simply "the driver". "Owner driver" and "group member driver" might be clearer because there will be two (possibly different) drivers involved. > +a group to control member devices of the group. > +This mechanism can > +be used, for example, to configure a member device before it is > +initialized by its driver. > +\footnote{The term "administration" is intended to be interpreted > +widely to include any kind of control. See specific commands > +for detail.} > + > +All the group administration commands are of the following form: > + > +\begin{lstlisting} > +struct virtio_admin_cmd { > + /* Device-readable part */ > + le16 opcode; > + /* > + * 1 - SR-IOV > + * 2 - 65535 reserved > + */ > + le16 group_type; > + /* unused, reserved for future extensions */ > + u8 reserved1[12]; > + le64 group_member_id; > + u8 command_specific_data[]; > + > + /* Device-writable part */ > + le16 status; > + le16 status_qualifier; > + /* unused, reserved for future extensions */ > + u8 reserved2[4]; > + u8 command_specific_result[]; > +}; > +\end{lstlisting} > + > +For all commands, \field{opcode}, \field{group_type} and if > +necessary \field{group_member_id} and \field{command_specific_data} are > +set by the driver, and the owner device sets \field{status} and if > +needed \field{status_qualifier} and > +\field{command_specific_result}. > + > +Generally, any unused device-readable fields are set to zero by the driv= er > +and ignored by the device. Any unused device-writeable fields are set t= o zero > +by the device and ignored by the driver. > + > +\field{opcode} specifies the command. The valid > +values for \field{opcode} can be found in the following table: > + > +\begin{tabular}{|l|l|} > +\hline > +opcode & Name & Command Description \\ > +\hline \hline > +0x0000 - 0x7FFF & - & Group administration commands \\ > +\hline > +0x8000 - 0xFFFF & - & Reserved \\ > +\hline > +\end{tabular} I thought all commands are "group administration commands" but this table makes it look like they are just a subset (0x0000 - 0x7FFF) of group administration commands, which is a paradox. > + > +The \field{group_type} specifies the group type identifier. > +The \field{group_member_id} specifies the member identifier within the g= roup. > +See section \ref{sec:Introduction / Terminology / Device group} > +for the definition of the group type identifier and group member > +identifier. > + > +The following table describes possible \field{status} values; > +to simplify common implementations, they are intentionally > +matching common \hyperref[intro:errno]{Linux error names and numbers}: > + > +\begin{tabular}{|l|l|l|} > +\hline > +Status (decimal) & Name & Description \\ > +\hline \hline > +00 & VIRTIO_ADMIN_STATUS_OK & successful completion \\ > +\hline > +22 & VIRTIO_ADMIN_STATUS_EINVAL & invalid command \\ > +\hline > +other & - & group administration command error \\ > +\hline > +\end{tabular} > + > +When \field{status} is VIRTIO_ADMIN_STATUS_OK, \field{status_qialifier} s/qialifier/qualifier/ > +is reserved and set to zero by the device. > + > +When \field{status} is VIRTIO_ADMIN_STATUS_EINVAL, > +the following table describes possible \field{status_qialifier} values: s/qialifier/qualifier/ > +\begin{tabular}{|l|l|l|} > +\hline > +Status & Name & Description \\ > +\hline \hline > +0x00 & VIRTIO_ADMIN_STATUS_Q_INVALID_COMMAND & command error: no add= itional information \\ > +\hline > +0x01 & VIRTIO_ADMIN_STATUS_Q_INVALID_OPCODE & unsupported or invali= d \field{opcode} \\ > +\hline > +0x02 & VIRTIO_ADMIN_STATUS_Q_INVALID_FIELD & unsupported or invalid= field within \field{command_specific_data} \\ > +\hline > +0x03 & VIRTIO_ADMIN_STATUS_Q_INVALID_GROUP & unsupported or invalid= \field{group_type} \\ > +\hline > +0x04 & VIRTIO_ADMIN_STATUS_Q_INVALID_MEMBER & unsupported or invali= d \field{group_member_id} \\ > +\hline > +0x05-0xFFFF & - & reserved for future use \\ > +\hline > +\end{tabular} > + > +Each command uses a different \field{command_specific_data} and > +\field{command_specific_result} structures and the length of > +\field{command_specific_data} and \field{command_specific_result} > +depends on these structures and is described separately or is > +implicit in the structure description. On more thing: Does the owner device see commands in order but may complete them in any order? I think this information might be useful just to make it clear that driver authors shouldn't make assumptions about ordering and completion order, e.g. pipelining a bunch of dependent commands doesn't work because the first command is not necessarily completed before the second command is started. --O8EmZxQ0wM/KxSAO Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEEhpWov9P5fNqsNXdanKSrs4Grc8gFAmQBAqMACgkQnKSrs4Gr c8gazAf/UtSaymfsHV+NSwe9KMyvr8FpY8vYHmmGl2OzqChXeB83vxTkuW57LRCo 2YrONqwv6Lk3C0juCVdONpQ8AtdS5sbIZZD6PxRYGEcJF2fwEK85YHRV4OKiVFx7 KXAeETLfTeVOIXfRjvgTASLPskM6RsQwymbhxJ4gP7zQ6aJNX7n+7MktBwH1zj/x X1J2iFFe60Vt8oKphDbfwe0Tk0XZ8vgBBHe7hT3g8V80o1LM+1DpK6hp+WB351mw fJSaqcrzTId8CPlDEKDbhuP2kwQVsg4nu5b7L6oYNuqegpwgi2gu7lJ3P3c2VROt x7gObNa0uPgfMtHkgLwqhpEd91iK0w== =pRl+ -----END PGP SIGNATURE----- --O8EmZxQ0wM/KxSAO--