drm/amdkfd: simplify vm_validate_pt_pd_bos

We don't need to validate and map root PD specially here,
it would be validated and mapped by amdgpu_vm_validate_pt_bos
if it is evicted.

The special case is when turning a GFX VM to a compute VM,
if vm_update_mode changed, we should make sure root PD gets
mapped. So just map root PD after updating vm->update_funcs
in amdgpu_vm_make_compute whether the vm_update_mode changed
or not.

v3:
 - Add some comments suggested by Christian.

v2:
 - Don't rename vm_validate_pt_pd_bos and make it public.
Signed-off-by: Lang Yu <Lang.Yu@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c

@@ -401,22 +401,8 @@ static int vm_validate_pt_pd_bos(struct amdgpu_vm *vm)
 		return ret;
 	}
 
-	ret = amdgpu_amdkfd_validate_vm_bo(NULL, pd);
-	if (ret) {
-		pr_err("failed to validate PD\n");
-		return ret;
-	}
-
 	vm->pd_phys_addr = amdgpu_gmc_pd_addr(vm->root.bo);
 
-	if (vm->use_cpu_for_update) {
-		ret = amdgpu_bo_kmap(pd, NULL);
-		if (ret) {
-			pr_err("failed to kmap PD, ret=%d\n", ret);
-			return ret;
-		}
-	}
-
 	return 0;
 }
 

drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c

@@ -2168,6 +2168,14 @@ int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm)
 	} else {
 		vm->update_funcs = &amdgpu_vm_sdma_funcs;
 	}
+	/*
+	 * Make sure root PD gets mapped. As vm_update_mode could be changed
+	 * when turning a GFX VM into a compute VM.
+	 */
+	r = vm->update_funcs->map_table(to_amdgpu_bo_vm(vm->root.bo));
+	if (r)
+		goto unreserve_bo;
+
 	dma_fence_put(vm->last_update);
 	vm->last_update = NULL;
 	vm->is_compute_context = true;