Add support to handle control virtqueue configurations per virtio
specification. The control virtqueue is implemented in software and no
hardware offloading is involved.
Control VQ configuration need task context, therefore all configurations
are handled in a workqueue created for the purpose.
Modifications are made to the memory registration code to allow for
saving a copy of itolb to be used by the control VQ to access the vring.
The max number of data virtqueus supported by the driver has been
updated to 2 since multiqueue is not supported at this stage and we need
to ensure consistency of VQ indices mapping to either data or control
VQ.
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210823052123.14909-6-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The current code treats an empty iotlb provdied in set_map() as a
special case and destroy the memory region object. This must not be done
since the virtqueue objects reference this MR. Doing so will cause the
driver unload to emit errors and log timeouts caused by the firmware
complaining on busy resources.
This patch treats an empty iotlb as any other change of mapping. In this
case, mlx5_vdpa_create_mr() will fail and the entire set_map() call to
fail.
This issue has not been encountered before but was seen to occur in a
non-official version of qemu. Since qemu is a userspace program, the
driver must protect against such case.
Fixes: 94abbccdf2 ("vdpa/mlx5: Add shared memory registration code")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210811053713.66658-1-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In order to support running vdpa using vritio_vdpa driver, we need to
create a different kind of MR, one that has 1:1 mapping, since the
addresses referring to virtqueues are dma addresses.
We create the 1:1 MR in mlx5_vdpa_dev_add() only in case firmware
supports the general capability umem_uid_0. The reason for that is that
1:1 MRs must be created with uid == 0 while virtqueue objects can be
created with uid == 0 only when the firmware capability is on.
If the set_map() callback is called with new translations provided
through iotlb, the driver will destroy the 1:1 MR and create a regular
one.
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210602085854.62690-1-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Before SF support was introduced, the DMA device was equal to
mdev->device which was in essence equal to pdev->dev.
With SF introduction this is no longer true. It has already been
handled for vhost_vdpa since the reference to the dma device can from
within mlx5_vdpa. With virtio_vdpa this broke. To fix this we set the
real dma device when initializing the device.
In addition, for the sake of consistency, previous references in the
code to the dma device are changed to vdev->dma_dev.
Fixes: d13a15d544 ("vdpa/mlx5: Use the correct dma device when registering memory")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210606053150.170489-1-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Set err = -ENOMEM if dma_map_sg_attrs() fails so the function reutrns
error.
Fixes: 94abbccdf2 ("vdpa/mlx5: Add shared memory registration code")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20210411083646.910546-1-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
In cases where the vdpa instance uses a SF (sub function), the DMA
device is the parent device. Use a function to retrieve the correct DMA
device.
Fixes: 1958fc2f07 ("net/mlx5: SF, Add auxiliary device driver")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Link: https://lore.kernel.org/r/20210408091047.4269-3-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
map_direct_mr() assumed that the number of scatter/gather entries
returned by dma_map_sg_attrs() was equal to the number of segments in
the sgl list. This led to wrong population of the mkey object. Fix this
by properly referring to the returned value.
The hardware expects each MTT entry to contain the DMA address of a
contiguous block of memory of size (1 << mr->log_size) bytes.
dma_map_sg_attrs() can coalesce several sg entries into a single
scatter/gather entry of contiguous DMA range so we need to scan the list
and refer to the size of each s/g entry.
In addition, get rid of fill_sg() which effect is overwritten by
populate_mtts().
Fixes: 94abbccdf2 ("vdpa/mlx5: Add shared memory registration code")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210107071845.GA224876@mtl-vdi-166.wap.labs.mlnx
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Fix to return the variable "err" from the error handling case instead
of "ret".
Fixes: 94abbccdf2 ("vdpa/mlx5: Add shared memory registration code")
Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Link: https://lore.kernel.org/r/20201026070637.164321-1-jingxiangfeng@huawei.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eli Cohen <elic@nvidia.com>
Cc: stable@vger.kernel.org
Acked-by: Jason Wang <jasowang@redhat.com>
If the kernel is unable to allocate memory for the variable dmr then
err will be returned without being set. Set err to -ENOMEM in this
case.
Fixes: 94abbccdf2 ("vdpa/mlx5: Add shared memory registration code")
Addresses-Coverity: ("Uninitialized variables")
Signed-off-by: Alex Dewar <alex.dewar@gmx.co.uk>
Link: https://lore.kernel.org/r/20200806185625.67344-1-alex.dewar@gmx.co.uk
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eli Cohen <eli@mellanox.com>
Add a front end VDPA driver that registers in the VDPA bus and provides
networking to a guest. The VDPA driver creates the necessary resources
on the VF it is driving such that data path will be offloaded.
Notifications are being communicated through the driver.
Currently, only VFs are supported. In subsequent patches we will have
devlink support to control which VF is used for VDPA and which function
is used for regular networking.
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Eli Cohen <eli@mellanox.com>
Link: https://lore.kernel.org/r/20200804162048.22587-13-eli@mellanox.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Add code to support registering address space region for the device. The
virtio driver can run as either:
1. Guest virtio driver
2. Userspace virtio driver on the host
3. Kernel virtio driver on the host
In any case a memory key object is required to provide access to memory
for the device.
This code will be shared by network or block driver implementations.
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Eli Cohen <eli@mellanox.com>
Link: https://lore.kernel.org/r/20200804162048.22587-12-eli@mellanox.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
