4 files changed, 22 insertions, 31 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 2da8dbd2553b..0c13fe96c7e3 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -292,12 +292,11 @@ static int ttm_bo_handle_move_mem(struct ttm_buffer_object *bo,
 	 */
 
 	if (!(new_man->flags & TTM_MEMTYPE_FLAG_FIXED)) {
-		if (bo->ttm == NULL) {
-			bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED);
-			ret = ttm_tt_create(bo, zero);
-			if (ret)
-				goto out_err;
-		}
+		bool zero = !(old_man->flags & TTM_MEMTYPE_FLAG_FIXED);
+
+		ret = ttm_tt_create(bo, zero);
+		if (ret)
+			goto out_err;
 
 		ret = ttm_tt_set_placement_caching(bo->ttm, mem->placement);
 		if (ret)
@@ -660,13 +659,8 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo,
 	placement.num_busy_placement = 0;
 	bdev->driver->evict_flags(bo, &placement);
 
-	if (!placement.num_placement && !placement.num_busy_placement) {
-		ret = ttm_bo_pipeline_gutting(bo);
-		if (ret)
-			return ret;
-
-		return ttm_tt_create(bo, false);
-	}
+	if (!placement.num_placement && !placement.num_busy_placement)
+		return ttm_bo_pipeline_gutting(bo);
 
 	evict_mem = bo->mem;
 	evict_mem.mm_node = NULL;
@@ -1195,13 +1189,8 @@ int ttm_bo_validate(struct ttm_buffer_object *bo,
 	/*
 	 * Remove the backing store if no placement is given.
 	 */
-	if (!placement->num_placement && !placement->num_busy_placement) {
-		ret = ttm_bo_pipeline_gutting(bo);
-		if (ret)
-			return ret;
-
-		return ttm_tt_create(bo, false);
-	}
+	if (!placement->num_placement && !placement->num_busy_placement)
+		return ttm_bo_pipeline_gutting(bo);
 
 	/*
 	 * Check whether we need to move buffer.
@@ -1218,14 +1207,6 @@ int ttm_bo_validate(struct ttm_buffer_object *bo,
 		ttm_flag_masked(&bo->mem.placement, new_flags,
 				~TTM_PL_MASK_MEMTYPE);
 	}
-	/*
-	 * We might need to add a TTM.
-	 */
-	if (bo->mem.mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) {
-		ret = ttm_tt_create(bo, true);
-		if (ret)
-			return ret;
-	}
 	return 0;
 }
 EXPORT_SYMBOL(ttm_bo_validate);
diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index f09b096ba4fd..5e0f3a9caedc 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -532,12 +532,15 @@ static int ttm_bo_kmap_ttm(struct ttm_buffer_object *bo,
 		.interruptible = false,
 		.no_wait_gpu = false
 	};
-	struct ttm_tt *ttm = bo->ttm;
+	struct ttm_tt *ttm;
 	pgprot_t prot;
 	int ret;
 
-	BUG_ON(!ttm);
+	ret = ttm_tt_create(bo, true);
+	if (ret)
+		return ret;
 
+	ttm = bo->ttm;
 	ret = ttm_tt_populate(ttm, &ctx);
 	if (ret)
 		return ret;
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index a43aa7275f12..82b893d4249f 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -349,6 +349,11 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 
 		};
 
+		if (ttm_tt_create(bo, true)) {
+			ret = VM_FAULT_OOM;
+			goto out_io_unlock;
+		}
+
 		ttm = bo->ttm;
 		if (ttm_tt_populate(bo->ttm, &ctx)) {
 			ret = VM_FAULT_OOM;
diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c
index 2ec448e1d663..e25d4097aa16 100644
--- a/drivers/gpu/drm/ttm/ttm_tt.c
+++ b/drivers/gpu/drm/ttm/ttm_tt.c
@@ -50,6 +50,9 @@ int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
 
 	dma_resv_assert_held(bo->base.resv);
 
+	if (bo->ttm)
+		return 0;
+
 	if (bdev->need_dma32)
 		page_flags |= TTM_PAGE_FLAG_DMA32;
 
@@ -67,7 +70,6 @@ int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
 		page_flags |= TTM_PAGE_FLAG_SG;
 		break;
 	default:
-		bo->ttm = NULL;
 		pr_err("Illegal buffer object type\n");
 		return -EINVAL;
 	}