> From: Christoph Hellwig <hch@xxxxxx>
> Sent: Thursday, August 26, 2021 12:19 AM
>
[...]
> diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
> index 71e0d3c4f1ac08..6bdfcb9264458c 100644
> --- a/drivers/vfio/vfio.c
> +++ b/drivers/vfio/vfio.c
> @@ -67,6 +67,9 @@ struct vfio_unbound_dev {
> struct list_head unbound_next;
> };
>
> +#define VFIO_EMULATED_IOMMU (1 << 0)
> +#define VFIO_NO_IOMMU (1 << 1)
it'd be helpful to have some comment here, as emulated iommu
is easy to be mixed with virtual iommu. At least here so-called iommu
doesn't refer to the exact iommu hardware. It's more about the
capability of DMA isolation and how it is implemented.
[...]
> @@ -391,8 +394,8 @@ static struct vfio_group *vfio_create_group(struct
> iommu_group *iommu_group,
> }
>
> dev = device_create(vfio.class, NULL,
> - MKDEV(MAJOR(vfio.group_devt), minor),
> - group, "%s%d", group->noiommu ? "noiommu-" :
> "",
> + MKDEV(MAJOR(vfio.group_devt), minor), group,
> "%s%d",
> + (group->flags & VFIO_NO_IOMMU) ? "noiommu-" :
> "",
what about introducing a group_no_iommu(group), given many duplicated
checks in this patch?
Thanks
Kevin
