Commits
Eric Auger committed 4644321fd3c
vfio/type1: handle case where IOMMU does not support PAGE_SIZE size Current vfio_pgsize_bitmap code hides the supported IOMMU page sizes smaller than PAGE_SIZE. As a result, in case the IOMMU does not support PAGE_SIZE page, the alignment check on map/unmap is done with larger page sizes, if any. This can fail although mapping could be done with pages smaller than PAGE_SIZE. This patch modifies vfio_pgsize_bitmap implementation so that, in case the IOMMU supports page sizes smaller than PAGE_SIZE we pretend PAGE_SIZE is supported and hide sub-PAGE_SIZE sizes. That way the user will be able to map/unmap buffers whose size/ start address is aligned with PAGE_SIZE. Pinning code uses that granularity while iommu driver can use the sub-PAGE_SIZE size to map the buffer. Signed-off-by: Eric Auger <eric.auger@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>