Some vIOMMU such as virtio-iommu use iova ranges from host side to
setup reserved ranges for passthrough device, so that guest will not
use an iova range beyond host support.

Use an uAPI of IOMMUFD to get iova ranges of host side and pass to
vIOMMU just like the legacy backend.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 hw/vfio/iommufd.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index c1daaf1c39..18a09d7f5a 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -348,6 +348,52 @@ static int vfio_ram_block_discard_disable(bool state)
     return ram_block_uncoordinated_discard_disable(state);
 }
 
+static int vfio_get_info_iova_range(VFIOIOMMUFDContainer *container,
+                                    uint32_t ioas_id)
+{
+    VFIOContainerBase *bcontainer = &container->bcontainer;
+    struct iommu_ioas_iova_ranges *info;
+    struct iommu_iova_range *iova_ranges;
+    int ret, sz, fd = container->be->fd;
+
+    info = g_malloc0(sizeof(*info));
+    info->size = sizeof(*info);
+    info->ioas_id = ioas_id;
+
+    ret = ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info);
+    if (ret && errno != EMSGSIZE) {
+        goto error;
+    }
+
+    sz = info->num_iovas * sizeof(struct iommu_iova_range);
+    info = g_realloc(info, sizeof(*info) + sz);
+    info->allowed_iovas = (uint64_t)(info + 1);
+
+    ret = ioctl(fd, IOMMU_IOAS_IOVA_RANGES, info);
+    if (ret) {
+        goto error;
+    }
+
+    iova_ranges = (struct iommu_iova_range *)info->allowed_iovas;
+
+    for (int i = 0; i < info->num_iovas; i++) {
+        Range *range = g_new(Range, 1);
+
+        range_set_bounds(range, iova_ranges[i].start, iova_ranges[i].last);
+        bcontainer->iova_ranges =
+            range_list_insert(bcontainer->iova_ranges, range);
+    }
+
+    g_free(info);
+    return 0;
+
+error:
+    ret = -errno;
+    g_free(info);
+    error_report("vfio/iommufd: Cannot get iova ranges: %m");
+    return ret;
+}
+
 static int iommufd_attach_device(char *name, VFIODevice *vbasedev,
                                  AddressSpace *as, Error **errp)
 {
@@ -425,6 +471,7 @@ static int iommufd_attach_device(char *name, VFIODevice *vbasedev,
     }
 
     bcontainer->pgsizes = qemu_real_host_page_size();
+    vfio_get_info_iova_range(container, ioas_id);
 
     bcontainer->listener = vfio_memory_listener;
     memory_listener_register(&bcontainer->listener, bcontainer->space->as);
-- 
2.34.1