On 2018年04月11日 21:22, Michael S. Tsirkin wrote:
On Wed, Apr 11, 2018 at 03:20:27PM +0800, Tiwei Bie wrote:
This patch introduces VHOST_USER_PROTOCOL_F_NEED_ALL_IOTLB
feature for vhost-user. By default, vhost-user backend needs
to query the IOTLBs from QEMU after meeting unknown IOVAs.
With this protocol feature negotiated, QEMU will provide all
the IOTLBs to vhost-user backend without waiting for the
queries from backend. This is helpful when using a hardware
accelerator which is not able to handle unknown IOVAs at the
Signed-off-by: Tiwei Bie<tiwei....@intel.com>
This is potentially a large amount of data to be sent
on a socket.
I had an impression that a hardware accelerator was using
VFIO anyway. Given this, can't we have QEMU program
the shadow IOMMU tables into VFIO directly?
So if we want to do this, my understanding is we need to implement the
driver inside qemu (or link it to qemu).