drm/amdgpu: Use kvmalloc_array for allocating VRAM manager nodes array

It can be quite big, and there's no need for it to be physically
contiguous. This is less likely to fail under memory pressure (has
actually happened while running piglit).

Cc: stable@vger.kernel.org
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -135,7 +135,8 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man,
 		num_nodes = DIV_ROUND_UP(mem->num_pages, pages_per_node);
 	}
 
-	nodes = kcalloc(num_nodes, sizeof(*nodes), GFP_KERNEL);
+	nodes = kvmalloc_array(num_nodes, sizeof(*nodes),
+			       GFP_KERNEL | __GFP_ZERO);
 	if (!nodes)
 		return -ENOMEM;
 
@@ -190,7 +191,7 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man,
 		drm_mm_remove_node(&nodes[i]);
 	spin_unlock(&mgr->lock);
 
-	kfree(nodes);
+	kvfree(nodes);
 	return r == -ENOSPC ? 0 : r;
 }
 
@@ -229,7 +230,7 @@ static void amdgpu_vram_mgr_del(struct ttm_mem_type_manager *man,
 	atomic64_sub(usage, &mgr->usage);
 	atomic64_sub(vis_usage, &mgr->vis_usage);
 
-	kfree(mem->mm_node);
+	kvfree(mem->mm_node);
 	mem->mm_node = NULL;
 }