From bac64f79264fd95b349004dd20b4ef7e9944fcb7 Mon Sep 17 00:00:00 2001
From: Kunkun Jiang <jiangkunkun@huawei.com>
Date: Fri, 18 Nov 2022 15:22:47 +0800
Subject: [PATCH 26/36] Revert "vfio: Force nested if iommu requires it"

This reverts commit e7eef5af743a53f0415267ebe9bba2e5f0e05816.

Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
---
 hw/vfio/common.c | 36 ++++++++----------------------------
 1 file changed, 8 insertions(+), 28 deletions(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index d7533637c9..6cb91e7ffd 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -2045,38 +2045,27 @@ static void vfio_put_address_space(VFIOAddressSpace *space)
  * vfio_get_iommu_type - selects the richest iommu_type (v2 first)
  */
 static int vfio_get_iommu_type(VFIOContainer *container,
-                               bool want_nested,
                                Error **errp)
 {
-    int iommu_types[] = { VFIO_TYPE1_NESTING_IOMMU,
-                          VFIO_TYPE1v2_IOMMU, VFIO_TYPE1_IOMMU,
+    int iommu_types[] = { VFIO_TYPE1v2_IOMMU, VFIO_TYPE1_IOMMU,
                           VFIO_SPAPR_TCE_v2_IOMMU, VFIO_SPAPR_TCE_IOMMU };
-    int i, ret = -EINVAL;
+    int i;
 
     for (i = 0; i < ARRAY_SIZE(iommu_types); i++) {
         if (ioctl(container->fd, VFIO_CHECK_EXTENSION, iommu_types[i])) {
-            if (iommu_types[i] == VFIO_TYPE1_NESTING_IOMMU && !want_nested) {
-                continue;
-            }
-            ret = iommu_types[i];
-            break;
+            return iommu_types[i];
         }
     }
-    if (ret < 0) {
-        error_setg(errp, "No available IOMMU models");
-    } else if (want_nested && ret != VFIO_TYPE1_NESTING_IOMMU) {
-        error_setg(errp, "Nested mode requested but not supported");
-        ret = -EINVAL;
-    }
-    return ret;
+    error_setg(errp, "No available IOMMU models");
+    return -EINVAL;
 }
 
 static int vfio_init_container(VFIOContainer *container, int group_fd,
-                               bool want_nested, Error **errp)
+                               Error **errp)
 {
     int iommu_type, dirty_log_manual_clear, ret;
 
-    iommu_type = vfio_get_iommu_type(container, want_nested, errp);
+    iommu_type = vfio_get_iommu_type(container, errp);
     if (iommu_type < 0) {
         return iommu_type;
     }
@@ -2188,14 +2177,6 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
     VFIOContainer *container;
     int ret, fd;
     VFIOAddressSpace *space;
-    IOMMUMemoryRegion *iommu_mr;
-    bool nested = false;
-
-    if (memory_region_is_iommu(as->root)) {
-        iommu_mr = IOMMU_MEMORY_REGION(as->root);
-        memory_region_iommu_get_attr(iommu_mr, IOMMU_ATTR_VFIO_NESTED,
-                                     (void *)&nested);
-    }
 
     space = vfio_get_address_space(as);
 
@@ -2276,7 +2257,7 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
     QLIST_INIT(&container->vrdl_list);
     QLIST_INIT(&container->dma_list);
 
-    ret = vfio_init_container(container, group->fd, nested, errp);
+    ret = vfio_init_container(container, group->fd, errp);
     if (ret) {
         goto free_container_exit;
     }
@@ -2288,7 +2269,6 @@ static int vfio_connect_container(VFIOGroup *group, AddressSpace *as,
     }
 
     switch (container->iommu_type) {
-    case VFIO_TYPE1_NESTING_IOMMU:
     case VFIO_TYPE1v2_IOMMU:
     case VFIO_TYPE1_IOMMU:
     {
-- 
2.27.0