This patch introduces the control virtqueue support for vDPA
simulator. This is a requirement for supporting advanced features like
multiqueue.
A requirement for control virtqueue is to isolate its memory access
from the rx/tx virtqueues. This is because when using vDPA device
for VM, the control virqueue is not directly assigned to VM. Userspace
(Qemu) will present a shadow control virtqueue to control for
recording the device states.
The isolation is done via the virtqueue groups and ASID support in
vDPA through vhost-vdpa. The simulator is extended to have:
1) three virtqueues: RXVQ, TXVQ and CVQ (control virtqueue)
2) two virtqueue groups: group 0 contains RXVQ and TXVQ; group 1
contains CVQ
3) two address spaces and the simulator simply implements the address
spaces by mapping it 1:1 to IOTLB.
For the VM use cases, userspace(Qemu) may set AS 0 to group 0 and AS 1
to group 1. So we have:
1) The IOTLB for virtqueue group 0 contains the mappings of guest, so
RX and TX can be assigned to guest directly.
2) The IOTLB for virtqueue group 1 contains the mappings of CVQ which
is the buffers that allocated and managed by VMM only. So CVQ of
vhost-vdpa is visible to VMM only. And Guest can not access the CVQ
of vhost-vdpa.
For the other use cases, since AS 0 is associated to all virtqueue
groups by default. All virtqueues share the same mapping by default.
To demonstrate the function, VIRITO_NET_F_CTRL_MACADDR is
implemented in the simulator for the driver to set mac address.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-20-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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 address space identifier could only be attached to
a specific virtqueue group.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Gautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-6-gdawar@xilinx.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The identical mapping used until now created issues when mapping
different virtual pages with the same physical address.
To solve this issue, we can use the iova module, to handle the IOVA
allocation.
For simplicity we use an IOVA allocator with byte granularity.
We add two new functions, vdpasim_map_range() and vdpasim_unmap_range(),
to handle the IOVA allocation and the registration into the IOMMU/IOTLB.
These functions are used by dma_map_ops callbacks.
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20210315163450.254396-2-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Enable user to create vdpasim net simulate devices.
Show vdpa management device that supports creating, deleting vdpa devices.
$ vdpa mgmtdev show
vdpasim_net:
supported_classes
net
$ vdpa mgmtdev show -jp
{
"show": {
"vdpasim_net": {
"supported_classes": {
"net"
}
}
}
Create a vdpa device of type networking named as "foo2" from
the management device vdpasim:
$ vdpa dev add mgmtdev vdpasim_net name foo2
Show the newly created vdpa device by its name:
$ vdpa dev show foo2
foo2: type network mgmtdev vdpasim_net vendor_id 0 max_vqs 2 max_vq_size 256
$ vdpa dev show foo2 -jp
{
"dev": {
"foo2": {
"type": "network",
"mgmtdev": "vdpasim_net",
"vendor_id": 0,
"max_vqs": 2,
"max_vq_size": 256
}
}
}
Delete the vdpa device after its use:
$ vdpa dev del foo2
Signed-off-by: Parav Pandit <parav@nvidia.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210105103203.82508-7-parav@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Introduce new vdpa_sim_net and vdpa_sim (core) drivers. This is a
preparation for adding a vdpa simulator module for block devices.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
[sgarzare: various cleanups/fixes]
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/r/20201215144256.155342-19-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Gautam Dawar
Stefano Garzarella
Parav Pandit
Max Gurtovoy