vfio: Record host IOMMU's available IO page sizes

Depending on the host IOMMU type we determine and record the available page
sizes for IOMMU translation.  We'll need this for other validation in
future patches.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NLaurent Vivier <lvivier@redhat.com>
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>

hw/vfio/common.c

@@ -677,6 +677,7 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as)
     if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1_IOMMU) ||
         ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU)) {
         bool v2 = !!ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU);
+        struct vfio_iommu_type1_info info;
 
         ret = ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &fd);
         if (ret) {
@@ -702,6 +703,15 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as)
          */
         container->min_iova = 0;
         container->max_iova = (hwaddr)-1;
+
+        /* Assume just 4K IOVA page size */
+        container->iova_pgsizes = 0x1000;
+        info.argsz = sizeof(info);
+        ret = ioctl(fd, VFIO_IOMMU_GET_INFO, &info);
+        /* Ignore errors */
+        if ((ret == 0) && (info.flags & VFIO_IOMMU_INFO_PGSIZES)) {
+            container->iova_pgsizes = info.iova_pgsizes;
+        }
     } else if (ioctl(fd, VFIO_CHECK_EXTENSION, VFIO_SPAPR_TCE_IOMMU)) {
         struct vfio_iommu_spapr_tce_info info;
 
@@ -744,6 +754,9 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as)
         }
         container->min_iova = info.dma32_window_start;
         container->max_iova = container->min_iova + info.dma32_window_size - 1;
+
+        /* Assume just 4K IOVA pages for now */
+        container->iova_pgsizes = 0x1000;
     } else {
         error_report("vfio: No available IOMMU models");
         ret = -EINVAL;

include/hw/vfio/vfio-common.h

@@ -71,6 +71,7 @@ typedef struct VFIOContainer {
      * future
      */
     hwaddr min_iova, max_iova;
+    uint64_t iova_pgsizes;
     QLIST_HEAD(, VFIOGuestIOMMU) giommu_list;
     QLIST_HEAD(, VFIOGroup) group_list;
     QLIST_ENTRY(VFIOContainer) next;