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 v4 link -> https://lists.gnu.org/archive/html/qemu-devel/2023-06/msg05174.html v5 link -> https://lists.gnu.org/archive/html/qemu-devel/2023-08/msg00255.html v6 link -> https://lists.gnu.org/archive/html/qemu-devel/2023-09/msg00987.html v7 link -> https://lists.gnu.org/archive/html/qemu-devel/2023-09/msg01190.html v8 link -> https://lists.gnu.org/archive/html/qemu-devel/2023-09/msg02284.html v8 -> v9: - Remove EOF whitespace in util/uuid.c
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, or pointers to the backend holding the resource - 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 36e9aab3c569d4c9ad780473596e18479838d1aa [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): util/uuid: add a hash function hw/display: introduce virtio-dmabuf vhost-user: add shared_object msg libvhost-user: handle shared_object msg MAINTAINERS | 7 + docs/interop/vhost-user.rst | 57 ++++++++ hw/display/meson.build | 1 + hw/display/virtio-dmabuf.c | 138 ++++++++++++++++++ hw/virtio/vhost-user.c | 168 ++++++++++++++++++++-- include/hw/virtio/vhost-backend.h | 3 + include/hw/virtio/virtio-dmabuf.h | 100 +++++++++++++ include/qemu/uuid.h | 2 + subprojects/libvhost-user/libvhost-user.c | 120 ++++++++++++++++ subprojects/libvhost-user/libvhost-user.h | 55 ++++++- tests/unit/meson.build | 1 + tests/unit/test-uuid.c | 27 ++++ tests/unit/test-virtio-dmabuf.c | 137 ++++++++++++++++++ util/uuid.c | 14 ++ 14 files changed, 817 insertions(+), 13 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 -- 2.41.0