On Wed, Dec 16, 2020 at 02:48:03PM +0800, Jason Wang wrote:

This patch introduces virtqueue groups to vDPA device. The virtqueue
group is the minimal set of virtqueues that must share an address
space. And the adddress space identifier could only be attached to
a specific virtqueue group.

A new mandated bus operation is introduced to get the virtqueue group
ID for a specific virtqueue.

All the vDPA device drivers were converted to simply support a single
virtqueue group.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/ifcvf/ifcvf_main.c   |  9 ++++++++-
 drivers/vdpa/mlx5/net/mlx5_vnet.c |  8 +++++++-
 drivers/vdpa/vdpa.c               |  4 +++-
 drivers/vdpa/vdpa_sim/vdpa_sim.c  | 11 ++++++++++-
 include/linux/vdpa.h              | 12 +++++++++---
 5 files changed, 37 insertions(+), 7 deletions(-)

Maybe consider calling it iotlb_group or iommu_group so the purpose of
the group is clear?