drm/amdgpu: Fix VM clean check method

amdgpu_vm_make_compute is used to turn a GFX VM into a compute VM,
the prerequisite is this VM is clean. Let's check if some page tables
are already filled , while not check if some mapping is already made.

Signed-off-by: Trigger Huang <Trigger.Huang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index a07c858..4f10f5a 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -2757,6 +2757,37 @@ error_free_sched_entity:
 }
 
 /**
+ * amdgpu_vm_check_clean_reserved - check if a VM is clean
+ *
+ * @adev: amdgpu_device pointer
+ * @vm: the VM to check
+ *
+ * check all entries of the root PD, if any subsequent PDs are allocated,
+ * it means there are page table creating and filling, and is no a clean
+ * VM
+ *
+ * Returns:
+ *     0 if this VM is clean
+ */
+static int amdgpu_vm_check_clean_reserved(struct amdgpu_device *adev,
+       struct amdgpu_vm *vm)
+{
+       enum amdgpu_vm_level root = adev->vm_manager.root_level;
+       unsigned int entries = amdgpu_vm_num_entries(adev, root);
+       unsigned int i = 0;
+
+       if (!(vm->root.entries))
+               return 0;
+
+       for (i = 0; i < entries; i++) {
+               if (vm->root.entries[i].base.bo)
+                       return -EINVAL;
+       }
+
+       return 0;
+}
+
+/**
  * amdgpu_vm_make_compute - Turn a GFX VM into a compute VM
  *
  * @adev: amdgpu_device pointer
@@ -2786,10 +2817,9 @@ int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm, uns
                return r;
 
        /* Sanity checks */
-       if (!RB_EMPTY_ROOT(&vm->va.rb_root) || vm->root.entries) {
-               r = -EINVAL;
+       r = amdgpu_vm_check_clean_reserved(adev, vm);
+       if (r)
                goto unreserve_bo;
-       }
 
        if (pasid) {
                unsigned long flags;