Re: [RFC 2/3] iommu: Account for dma_mask and iommu aperture in IOVA reserved regions

2020-09-29 Thread Auger Eric
Hi Christoph, On 9/29/20 8:03 AM, Christoph Hellwig wrote: > On Mon, Sep 28, 2020 at 09:50:36PM +0200, Eric Auger wrote: >> VFIO currently exposes the usable IOVA regions through the >> VFIO_IOMMU_GET_INFO ioctl. However it fails to take into account >> the dma_mask of the devices within the conta

Re: [RFC 2/3] iommu: Account for dma_mask and iommu aperture in IOVA reserved regions

2020-09-28 Thread Christoph Hellwig
On Mon, Sep 28, 2020 at 09:50:36PM +0200, Eric Auger wrote: > VFIO currently exposes the usable IOVA regions through the > VFIO_IOMMU_GET_INFO ioctl. However it fails to take into account > the dma_mask of the devices within the container. The top limit > currently is defined by the iommu aperture.

[RFC 2/3] iommu: Account for dma_mask and iommu aperture in IOVA reserved regions

2020-09-28 Thread Eric Auger
VFIO currently exposes the usable IOVA regions through the VFIO_IOMMU_GET_INFO ioctl. However it fails to take into account the dma_mask of the devices within the container. The top limit currently is defined by the iommu aperture. So, for instance, if the IOMMU supports up to 48bits, it may give