[PATCH 2/2] vfio/iommufd: Support unmap all in one ioctl()

[Zhenzhong Duan <zhenzhong.duan@intel.com>]

IOMMUFD kernel uAPI supports unmapping whole address space in one call with
[iova, size] set to [0, UINT64_MAX], this can simplify iommufd_cdev_unmap()
a bit.  See iommufd_ioas_unmap() in kernel for details.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/vfio/iommufd.c | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index 8c27222f75..02e4b8774a 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -65,21 +65,9 @@ static int iommufd_cdev_unmap(const VFIOContainerBase *bcontainer,
     const VFIOIOMMUFDContainer *container =
         container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
 
-    /* unmap in halves */
     if (unmap_all) {
-        Int128 llsize = int128_rshift(int128_2_64(), 1);
-        int ret;
-
-        ret = iommufd_backend_unmap_dma(container->be, container->ioas_id,
-                                        0, int128_get64(llsize));
-
-        if (ret == 0) {
-            ret = iommufd_backend_unmap_dma(container->be, container->ioas_id,
-                                            int128_get64(llsize),
-                                            int128_get64(llsize));
-        }
-
-        return ret;
+        assert(!iova && !size);
+        size = UINT64_MAX;
     }
 
     /* TODO: Handle dma_unmap_bitmap with iotlb args (migration) */
-- 
2.47.1