Control virtqueue is used by networking device for accepting various commands from the driver. It's a must to support multiqueue and other configurations.
Shadow VirtQueue (SVQ) already makes possible migration of virtqueue states, effectively intercepting them so qemu can track what regions of memory are dirty because device action and needs migration. However, this does not solve networking device state seen by the driver because CVQ messages, like changes on MAC addresses from the driver. To solve that, this series uses SVQ infraestructure proposed at SVQ to intercept networking control messages used by the device. This way, qemu is able to update VirtIONet device model and to migrate it. You can run qemu in two modes after applying this series: only intercepting cvq with x-cvq-svq=on or intercept all the virtqueues adding cmdline x-svq=on: -netdev type=vhost-vdpa,vhostdev=/dev/vhost-vdpa-0,id=vhost-vdpa0,x-cvq-svq=on,x-svq=on The most updated kernel part of ASID is proposed at [1]. Other modes without x-cvq-svq have been not tested with this series. Other vq cmd commands than set mac are not tested. Some details like error control are not 100% tested neither. The firsts patches will be proposed sepratedly. Comments are welcomed on every aspect of the patch. Changes from rfc v3: * Fix bad returning of descriptors to SVQ list. Changes from rfc v2: * Fix use-after-free. Changes from rfc v1: * Rebase to latest master. * Configure ASID instead of assuming cvq asid != data vqs asid. * Update device model so (MAC) state can be migrated too. [1] https://lkml.kernel.org/kvm/20220224212314.1326-1-gda...@xilinx.com/ Eugenio Pérez (20): vhost: Fix bad return of descriptors util: Return void on iova_tree_remove vdpa: Add x-svq to NetdevVhostVDPAOptions vhost: move descriptor translation to vhost_svq_vring_write_descs vdpa: Fix index calculus at vhost_vdpa_svqs_start virtio-net: use g_memdup2() instead of unsafe g_memdup() virtio-net: Expose ctrl virtqueue logic vdpa: Extract get geatures part from vhost_vdpa_get_max_queue_pairs virtio: Make virtqueue_alloc_element non-static vhost: Add SVQElement vhost: Add custom used buffer callback vdpa: control virtqueue support on shadow virtqueue vhost: Add vhost_iova_tree_find vdpa: Add map/unmap operation callback to SVQ vhost: Add vhost_svq_inject vdpa: add NetClientState->start() callback vdpa: Add vhost_vdpa_start_control_svq vhost: Update kernel headers vdpa: Add asid attribute to vdpa device vdpa: Add x-cvq-svq qapi/net.json | 13 +- hw/virtio/vhost-iova-tree.h | 2 + hw/virtio/vhost-shadow-virtqueue.h | 46 ++- include/hw/virtio/vhost-vdpa.h | 5 + include/hw/virtio/virtio-net.h | 3 + include/hw/virtio/virtio.h | 1 + include/net/net.h | 2 + include/qemu/iova-tree.h | 4 +- include/standard-headers/linux/vhost_types.h | 11 +- linux-headers/linux/vhost.h | 25 +- hw/net/vhost_net.c | 4 + hw/net/virtio-net.c | 82 +++-- hw/virtio/vhost-iova-tree.c | 14 + hw/virtio/vhost-shadow-virtqueue.c | 255 ++++++++++--- hw/virtio/vhost-vdpa.c | 70 +++- hw/virtio/virtio.c | 2 +- net/vhost-vdpa.c | 368 +++++++++++++++++-- util/iova-tree.c | 4 +- 18 files changed, 779 insertions(+), 132 deletions(-) -- 2.27.0
