v1 link -> https://lists.gnu.org/archive/html/qemu-devel/2023-05/msg00598.html v2 link -> https://lists.gnu.org/archive/html/qemu-devel/2023-05/msg04530.html v3 link -> https://lists.gnu.org/archive/html/qemu-devel/2023-05/msg06126.html v3 -> v4: - Split the different message types for shared objects into different messages - Add a vhost-user feature bit to negotiate the shared object feature - Minor improvements following suggestions
This patch covers the required steps to add support for virtio cross-device resource sharing[1], which support is already available in the kernel. The main usecase will be sharing dma buffers from virtio-gpu devices (as the exporter -see VIRTIO_GPU_CMD_RESOURCE_ASSIGN_UUID in [2]), to virtio-video (under discussion) devices (as the buffer-user or importer). Therefore, even though virtio specs talk about resources or objects[3], this patch adds the infrastructure with dma-bufs in mind. Note that virtio specs let the devices themselves define what a vitio object is. These are the main parts that are covered in the patch: - Add hash function to uuid module - Shared resources table, to hold all resources that can be shared in the host and their assigned UUID - Internal shared table API for virtio devices to add, lookup and remove resources - Unit test to verify the API - New messages to the vhost-user protocol to allow backend to interact with the shared table API through the control socket - New vhost-user feature bit to enable shared objects feature Applies cleanly to b455ce4c2f300c8ba47cba7232dd03261368a4cb [1] - https://lwn.net/Articles/828988/ [2] - https://docs.oasis-open.org/virtio/virtio/v1.2/csd01/virtio-v1.2-csd01.html#x1-3730006 [3] - https://docs.oasis-open.org/virtio/virtio/v1.2/csd01/virtio-v1.2-csd01.html#x1-10500011 Albert Esteve (4): uuid: add a hash function virtio-dmabuf: introduce virtio-dmabuf vhost-user: add shared_object msg vhost-user: refactor send_resp code MAINTAINERS | 7 ++ docs/interop/vhost-user.rst | 42 ++++++++ hw/display/meson.build | 1 + hw/display/virtio-dmabuf.c | 90 +++++++++++++++++ hw/virtio/vhost-user.c | 115 +++++++++++++++++++--- include/hw/virtio/virtio-dmabuf.h | 59 +++++++++++ include/qemu/uuid.h | 2 + subprojects/libvhost-user/libvhost-user.c | 101 +++++++++++++++++++ subprojects/libvhost-user/libvhost-user.h | 53 +++++++++- tests/unit/meson.build | 1 + tests/unit/test-uuid.c | 27 +++++ tests/unit/test-virtio-dmabuf.c | 112 +++++++++++++++++++++ util/uuid.c | 14 +++ 13 files changed, 610 insertions(+), 14 deletions(-) create mode 100644 hw/display/virtio-dmabuf.c create mode 100644 include/hw/virtio/virtio-dmabuf.h create mode 100644 tests/unit/test-virtio-dmabuf.c -- 2.40.0