vfio/container: Implement HostIOMMUDeviceClass::realize() handler

The realize function populates the capabilities. For now only the
aw_bits caps is computed for legacy backend.

Introduce a helper function vfio_device_get_aw_bits() which calls
range_get_last_bit() to get host aw_bits and package it in
HostIOMMUDeviceCaps for query with .get_cap(). This helper will
also be used by iommufd backend.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Zhenzhong Duan 2024-06-05 16:30:32 +08:00 committed by Cédric Le Goater
parent 6f274444c5
commit d441e05e26
3 changed files with 37 additions and 0 deletions

View file

@ -658,3 +658,20 @@ void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
vbasedev->ram_block_discard_allowed = ram_discard;
}
int vfio_device_get_aw_bits(VFIODevice *vdev)
{
/*
* iova_ranges is a sorted list. For old kernels that support
* VFIO but not support query of iova ranges, iova_ranges is NULL,
* in this case HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX(64) is returned.
*/
GList *l = g_list_last(vdev->bcontainer->iova_ranges);
if (l) {
Range *range = l->data;
return range_get_last_bit(range) + 1;
}
return HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX;
}