[PATCH 1/2] vhost-vdpa: skip ram device from the IOTLB mapping

[Jason Wang <jasowang@redhat.com>]

vDPA is not tie to any specific hardware, for safety and simplicity,
vhost-vDPA doesn't allow MMIO area to be mapped via IOTLB. Only the
doorbell could be mapped via mmap(). So this patch exclude skip the
ram device from the IOTLB mapping.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 hw/virtio/vhost-vdpa.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 01d2101d09..dd4321bac2 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -27,6 +27,8 @@ static bool vhost_vdpa_listener_skipped_section(MemoryRegionSection *section)
 {
     return (!memory_region_is_ram(section->mr) &&
             !memory_region_is_iommu(section->mr)) ||
+           /* vhost-vDPA doesn't allow MMIO to be mapped  */
+            memory_region_is_ram_device(section->mr) ||
            /*
             * Sizing an enabled 64-bit BAR can cause spurious mappings to
             * addresses in the upper part of the 64-bit address space.  These
@@ -171,22 +173,12 @@ static void vhost_vdpa_listener_region_add(MemoryListener *listener,
                              vaddr, section->readonly);
     if (ret) {
         error_report("vhost vdpa map fail!");
-        if (memory_region_is_ram_device(section->mr)) {
-            /* Allow unexpected mappings not to be fatal for RAM devices */
-            error_report("map ram fail!");
-          return ;
-        }
         goto fail;
     }
 
     return;
 
 fail:
-    if (memory_region_is_ram_device(section->mr)) {
-        error_report("failed to vdpa_dma_map. pci p2p may not work");
-        return;
-
-    }
     /*
      * On the initfn path, store the first error in the container so we
      * can gracefully fail.  Runtime, there's not much we can do other
-- 
2.25.1