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Wed, 30 Mar 2022 11:04:59 -0700 From: Gautam Dawar To: "Michael S. Tsirkin" , Jason Wang , , , , CC: , , , , , , , , , Gautam Dawar , Wu Zongyong , Christophe JAILLET , Eli Cohen , Zhu Lingshan , Stefano Garzarella , Xie Yongji , Si-Wei Liu , Parav Pandit , Longpeng , Dan Carpenter , Zhang Min Subject: [PATCH v2 00/19] Control VQ support in vDPA Date: Wed, 30 Mar 2022 23:33:40 +0530 Message-ID: <20220330180436.24644-1-gdawar@xilinx.com> X-Mailer: git-send-email 2.25.0 MIME-Version: 1.0 X-EOPAttributedMessage: 1 X-MS-Office365-Filtering-Correlation-Id: 10b13f95-6668-488c-1450-08da1277d1da X-MS-TrafficTypeDiagnostic: BYAPR02MB4485:EE_|BN1NAM02FT032:EE_|SA0PR02MB7243:EE_ X-Microsoft-Antispam-PRVS: X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam-Untrusted: BCL:0; X-Microsoft-Antispam-Message-Info-Original: 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 X-Forefront-Antispam-Report-Untrusted: CIP:149.199.62.198;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:xsj-pvapexch02.xlnx.xilinx.com;PTR:unknown-62-198.xilinx.com;CAT:NONE;SFS:(13230001)(4636009)(46966006)(40470700004)(36840700001)(40460700003)(8936002)(9786002)(70206006)(4326008)(8676002)(70586007)(26005)(36756003)(336012)(426003)(2906002)(83380400001)(1076003)(2616005)(36860700001)(7696005)(186003)(7416002)(508600001)(44832011)(6666004)(316002)(356005)(82310400004)(5660300002)(84970400001)(7636003)(47076005)(54906003)(110136005)(102446001);DIR:OUT;SFP:1101; X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR02MB4485 X-MS-Exchange-Transport-CrossTenantHeadersStripped: BN1NAM02FT032.eop-nam02.prod.protection.outlook.com X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id-Prvs: 28bb2f67-7144-48d7-5952-08da1277cf67 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:20.83.241.18;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mailrelay000000.14r1f435wfvunndds3vy4cdalc.xx.internal.cloudapp.net;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230001)(4636009)(36840700001)(46966006)(40470700004)(70206006)(26005)(36860700001)(186003)(7416002)(54906003)(36756003)(8676002)(4326008)(5660300002)(47076005)(6666004)(426003)(110136005)(1076003)(44832011)(336012)(40460700003)(9786002)(8936002)(84970400001)(82310400004)(7696005)(81166007)(2906002)(316002)(508600001)(83380400001)(2616005)(102446001)(36900700001);DIR:OUT;SFP:1101; X-OriginatorOrg: xilinx.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Mar 2022 18:05:05.5922 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 10b13f95-6668-488c-1450-08da1277d1da X-MS-Exchange-CrossTenant-Id: 657af505-d5df-48d0-8300-c31994686c5c X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=657af505-d5df-48d0-8300-c31994686c5c;Ip=[20.83.241.18];Helo=[mailrelay000000.14r1f435wfvunndds3vy4cdalc.xx.internal.cloudapp.net] X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: TreatMessagesAsInternal-BN1NAM02FT032.eop-nam02.prod.protection.outlook.com X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR02MB7243 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi All: This series tries to add the support for control virtqueue in vDPA. Control virtqueue is used by networking device for accepting various commands from the driver. It's a must to support multiqueue and other configurations. When used by vhost-vDPA bus driver for VM, the control virtqueue should be shadowed via userspace VMM (Qemu) instead of being assigned directly to Guest. This is because Qemu needs to know the device state in order to start and stop device correctly (e.g for Live Migration). This requies to isolate the memory mapping for control virtqueue presented by vhost-vDPA to prevent guest from accessing it directly. To achieve this, vDPA introduce two new abstractions: - address space: identified through address space id (ASID) and a set of memory mapping in maintained - virtqueue group: the minimal set of virtqueues that must share an address space Device needs to advertise the following attributes to vDPA: - the number of address spaces supported in the device - the number of virtqueue groups supported in the device - the mappings from a specific virtqueue to its virtqueue groups The mappings from virtqueue to virtqueue groups is fixed and defined by vDPA device driver. E.g: - For the device that has hardware ASID support, it can simply advertise a per virtqueue group. - For the device that does not have hardware ASID support, it can simply advertise a single virtqueue group that contains all virtqueues. Or if it wants a software emulated control virtqueue, it can advertise two virtqueue groups, one is for cvq, another is for the rest virtqueues. vDPA also allow to change the association between virtqueue group and address space. So in the case of control virtqueue, userspace VMM(Qemu) may use a dedicated address space for the control virtqueue group to isolate the memory mapping. The vhost/vhost-vDPA is also extend for the userspace to: - query the number of virtqueue groups and address spaces supported by the device - query the virtqueue group for a specific virtqueue - assocaite a virtqueue group with an address space - send ASID based IOTLB commands This will help userspace VMM(Qemu) to detect whether the control vq could be supported and isolate memory mappings of control virtqueue from the others. To demonstrate the usage, vDPA simulator is extended to support setting MAC address via a emulated control virtqueue. Please review. Changes since RFC v2: - Fixed memory leak for asid 0 in vhost_vdpa_remove_as() - Removed unnecessary NULL check for iotlb in vhost_vdpa_unmap() and changed its return type to void. - Removed insignificant used_as member field from struct vhost_vdpa. - Corrected the iommu parameter in call to vringh_set_iotlb() from vdpasim_set_group_asid() - Fixed build errors with vdpa_sim_net - Updated alibaba, vdpa_user and virtio_pci vdpa parent drivers to call updated vDPA APIs and ensured successful build - Tested control (MAC address configuration) and data-path using single virtqueue pair on Xilinx (now AMD) SN1022 SmartNIC device and vdpa_sim_net software device using QEMU release at [1] - Removed two extra blank lines after set_group_asid() in include/linux/vdpa.h Changes since v1: - Rebased the v1 patch series on vhost branch of MST vhost git repo git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git/log/?h=vhost - Updates to accommodate vdpa_sim changes from monolithic module in kernel used v1 patch series to current modularized class (net, block) based approach. - Added new attributes (ngroups and nas) to "vdpasim_dev_attr" and propagated them from vdpa_sim_net to vdpa_sim - Widened the data-type for "asid" member of vhost_msg_v2 to __u32 to accommodate PASID - Fixed the buildbot warnings - Resolved all checkpatch.pl errors and warnings - Tested both control and datapath with Xilinx Smartnic SN1000 series device using QEMU implementing the Shadow virtqueue and support for VQ groups and ASID available at [1] Changes since RFC: - tweak vhost uAPI documentation - switch to use device specific IOTLB really in patch 4 - tweak the commit log - fix that ASID in vhost is claimed to be 32 actually but 16bit actually - fix use after free when using ASID with IOTLB batching requests - switch to use Stefano's patch for having separated iov - remove unused "used_as" variable - fix the iotlb/asid checking in vhost_vdpa_unmap() [1] Development QEMU release with support for SVQ, VQ groups and ASID: github.com/eugpermar/qemu/releases/tag/vdpa_sw_live_migration.d%2F asid_groups-v1.d%2F00 Thanks Gautam Dawar (19): vhost: move the backend feature bits to vhost_types.h virtio-vdpa: don't set callback if virtio doesn't need it vhost-vdpa: passing iotlb to IOMMU mapping helpers vhost-vdpa: switch to use vhost-vdpa specific IOTLB vdpa: introduce virtqueue groups vdpa: multiple address spaces support vdpa: introduce config operations for associating ASID to a virtqueue group vhost_iotlb: split out IOTLB initialization vhost: support ASID in IOTLB API vhost-vdpa: introduce asid based IOTLB vhost-vdpa: introduce uAPI to get the number of virtqueue groups vhost-vdpa: introduce uAPI to get the number of address spaces vhost-vdpa: uAPI to get virtqueue group id vhost-vdpa: introduce uAPI to set group ASID vhost-vdpa: support ASID based IOTLB API vdpa_sim: advertise VIRTIO_NET_F_MTU vdpa_sim: factor out buffer completion logic vdpa_sim: filter destination mac address vdpasim: control virtqueue support drivers/vdpa/alibaba/eni_vdpa.c | 2 +- drivers/vdpa/ifcvf/ifcvf_main.c | 8 +- drivers/vdpa/mlx5/net/mlx5_vnet.c | 11 +- drivers/vdpa/vdpa.c | 5 + drivers/vdpa/vdpa_sim/vdpa_sim.c | 100 ++++++++-- drivers/vdpa/vdpa_sim/vdpa_sim.h | 3 + drivers/vdpa/vdpa_sim/vdpa_sim_net.c | 169 +++++++++++++---- drivers/vdpa/vdpa_user/vduse_dev.c | 3 +- drivers/vdpa/virtio_pci/vp_vdpa.c | 2 +- drivers/vhost/iotlb.c | 23 ++- drivers/vhost/vdpa.c | 267 +++++++++++++++++++++------ drivers/vhost/vhost.c | 23 ++- drivers/vhost/vhost.h | 4 +- drivers/virtio/virtio_vdpa.c | 2 +- include/linux/vdpa.h | 44 ++++- include/linux/vhost_iotlb.h | 2 + include/uapi/linux/vhost.h | 26 ++- include/uapi/linux/vhost_types.h | 11 +- 18 files changed, 563 insertions(+), 142 deletions(-) Reviewed-by: Eugenio Pérez