This patch implements the vq notification mapping support for
vhost-vDPA. This is simply done by using mmap()/munmap() for the
vhost-vDPA fd during device start/stop. For the device without
notification mapping support, we fall back to eventfd based
notification gracefully.
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
vDPA is not tie to any specific hardware, for safety and simplicity,
vhost-vDPA doesn't allow MMIO area to be mapped via IOTLB. Only the
doorbell could be mapped via mmap(). So this patch exclude skip the
ram device from the IOTLB mapping.
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Fix uninitialized value issues reported by Coverity:
Field 'msg.reserved' is uninitialized when calling write().
Fixes: a5bd05800f ("vhost-vdpa: batch updating IOTLB mappings")
Reported-by: Coverity (CID 1432864: UNINIT)
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201028154004.776760-1-philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
To speed up the memory mapping updating between vhost-vDPA and vDPA
device driver, this patch passes the IOTLB batching flags via IOTLB
API. Two new flags was introduced, VHOST_IOTLB_BATCH_BEGIN is a hint
that a bathced IOTLB updating may be initiated from the
userspace. VHOST_IOTLB_BATCH_END is a hint that userspace has finished
the updating:
VHOST_IOTLB_BATCH_BEGIN
VHOST_IOTLB_UPDATE/VHOST_IOTLB_INVALIDATE
...
VHOST_IOTLB_BATCH_END
Vhost-vDPA can then know that all mappings has been set and can do
optimization like passing all the mappings to the vDPA device driver.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20200907104903.31551-4-jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Currently we have 2 types of vhost backends in QEMU: vhost kernel and
vhost-user. The above patch provides a generic device for vDPA purpose,
this vDPA device exposes to user space a non-vendor-specific configuration
interface for setting up a vhost HW accelerator, this patch set introduces
a third vhost backend called vhost-vdpa based on the vDPA interface.
Vhost-vdpa usage:
qemu-system-x86_64 -cpu host -enable-kvm \
......
-netdev type=vhost-vdpa,vhostdev=/dev/vhost-vdpa-id,id=vhost-vdpa0 \
-device virtio-net-pci,netdev=vhost-vdpa0,page-per-vq=on \
Signed-off-by: Lingshan zhu <lingshan.zhu@intel.com>
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Cindy Lu <lulu@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20200701145538.22333-14-lulu@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
