Re: [PATCH v2 0/1] Implementation of resource_query_layout

[Zhang, Julia]

I see, I will implement this. Thank you very much.

On 2023/12/27 09:29, Gurchetan Singh wrote:
> 
> 
> On Thu, Dec 21, 2023 at 2:01 AM Julia Zhang <julia.zhang@xxxxxxx <mailto:julia.zhang@xxxxxxx>> wrote:
> 
>     Hi all,
> 
>     Sorry to late reply. This is v2 of the implementation of
>     resource_query_layout. This adds a new ioctl to let guest query information
>     of host resource, which is originally from Daniel Stone. We add some
>     changes to support query the correct stride of host resource before it's
>     created, which is to support to blit data from dGPU to virtio iGPU for dGPU
>     prime feature.
> 
>     Changes from v1 to v2:
>     -Squash two patches to a single patch.
>     -A small modification of VIRTIO_GPU_F_RESOURCE_QUERY_LAYOUT
> 
> 
>     Below is description of v1:
>     This add implementation of resource_query_layout to get the information of
>     how the host has actually allocated the buffer. This function is now used
>     to query the stride for guest linear resource for dGPU prime on guest VMs.
> 
> 
> You can use a context specific protocol or even the virgl capabilities [for a linear strided resource].  For example, Sommelier does the following:
> 
> https://chromium.googlesource.com/chromiumos/platform2/+/HEAD/vm_tools/sommelier/virtualization/virtgpu_channel.cc#549 <https://chromium.googlesource.com/chromiumos/platform2/+/HEAD/vm_tools/sommelier/virtualization/virtgpu_channel.cc#549>
> 
> i.e, you should be able to avoid extra ioctl + hypercall.
>  
> 
> 
>     v1 of kernel side:
>      https:
>     //lore.kernel.org/xen-devel/20231110074027.24862-1-julia.zhang@xxxxxxx/T/#t <http://lore.kernel.org/xen-devel/20231110074027.24862-1-julia.zhang@xxxxxxx/T/#t>
> 
>     v1 of qemu side:
>     https:
>     //lore.kernel.org/qemu-devel/20231110074027.24862-1-julia.zhang@xxxxxxx/T/#t <http://lore.kernel.org/qemu-devel/20231110074027.24862-1-julia.zhang@xxxxxxx/T/#t>
> 
>     Daniel Stone (1):
>       drm/virtio: Implement RESOURCE_GET_LAYOUT ioctl
> 
>      drivers/gpu/drm/virtio/virtgpu_drv.c   |  1 +
>      drivers/gpu/drm/virtio/virtgpu_drv.h   | 22 ++++++++-
>      drivers/gpu/drm/virtio/virtgpu_ioctl.c | 66 ++++++++++++++++++++++++++
>      drivers/gpu/drm/virtio/virtgpu_kms.c   |  8 +++-
>      drivers/gpu/drm/virtio/virtgpu_vq.c    | 63 ++++++++++++++++++++++++
>      include/uapi/drm/virtgpu_drm.h         | 21 ++++++++
>      include/uapi/linux/virtio_gpu.h        | 30 ++++++++++++
>      7 files changed, 208 insertions(+), 3 deletions(-)
> 
>     -- 
>     2.34.1
>