diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 7c8e8be774f1..394ccb13eaed 100644
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -51,8 +51,8 @@ static void ttm_bo_mem_space_debug(struct ttm_buffer_object *bo,
 	struct ttm_resource_manager *man;
 	int i, mem_type;
 
-	drm_printf(&p, "No space for %p (%lu pages, %zuK, %zuM)\n",
-		   bo, bo->resource->num_pages, bo->base.size >> 10,
+	drm_printf(&p, "No space for %p (%lu size, %zuK, %zuM)\n",
+		   bo, bo->resource->size, bo->base.size >> 10,
 		   bo->base.size >> 20);
 	for (i = 0; i < placement->num_placement; i++) {
 		mem_type = placement->placement[i].mem_type;
diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index fa04e62202c1..da5493f789df 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -173,7 +173,7 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
 
 	clear = src_iter->ops->maps_tt && (!ttm || !ttm_tt_is_populated(ttm));
 	if (!(clear && ttm && !(ttm->page_flags & TTM_TT_FLAG_ZERO_ALLOC)))
-		ttm_move_memcpy(clear, dst_mem->num_pages, dst_iter, src_iter);
+		ttm_move_memcpy(clear, PFN_UP(dst_mem->size), dst_iter, src_iter);
 
 	if (!src_iter->ops->maps_tt)
 		ttm_kmap_iter_linear_io_fini(&_src_iter.io, bdev, src_mem);
@@ -357,9 +357,9 @@ int ttm_bo_kmap(struct ttm_buffer_object *bo,
 
 	map->virtual = NULL;
 	map->bo = bo;
-	if (num_pages > bo->resource->num_pages)
+	if (num_pages > PFN_UP(bo->resource->size))
 		return -EINVAL;
-	if ((start_page + num_pages) > bo->resource->num_pages)
+	if ((start_page + num_pages) > PFN_UP(bo->resource->size))
 		return -EINVAL;
 
 	ret = ttm_mem_io_reserve(bo->bdev, bo->resource);
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index 38119311284d..876e7d07273c 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -217,7 +217,7 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
 	page_last = vma_pages(vma) + vma->vm_pgoff -
 		drm_vma_node_start(&bo->base.vma_node);
 
-	if (unlikely(page_offset >= bo->resource->num_pages))
+	if (unlikely(page_offset >= PFN_UP(bo->resource->size)))
 		return VM_FAULT_SIGBUS;
 
 	prot = ttm_io_prot(bo, bo->resource, prot);
@@ -412,7 +412,7 @@ int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
 		 << PAGE_SHIFT);
 	int ret;
 
-	if (len < 1 || (offset + len) >> PAGE_SHIFT > bo->resource->num_pages)
+	if (len < 1 || (offset + len) > bo->resource->size)
 		return -EIO;
 
 	ret = ttm_bo_reserve(bo, true, false, NULL);
diff --git a/drivers/gpu/drm/ttm/ttm_range_manager.c b/drivers/gpu/drm/ttm/ttm_range_manager.c
index f7c16c46cfbc..0a8bc0b7f380 100644
--- a/drivers/gpu/drm/ttm/ttm_range_manager.c
+++ b/drivers/gpu/drm/ttm/ttm_range_manager.c
@@ -83,7 +83,7 @@ static int ttm_range_man_alloc(struct ttm_resource_manager *man,
 
 	spin_lock(&rman->lock);
 	ret = drm_mm_insert_node_in_range(mm, &node->mm_nodes[0],
-					  node->base.num_pages,
+					  PFN_UP(node->base.size),
 					  bo->page_alignment, 0,
 					  place->fpfn, lpfn, mode);
 	spin_unlock(&rman->lock);
diff --git a/drivers/gpu/drm/ttm/ttm_resource.c b/drivers/gpu/drm/ttm/ttm_resource.c
index a729c32a1e48..f9cce0727d40 100644
--- a/drivers/gpu/drm/ttm/ttm_resource.c
+++ b/drivers/gpu/drm/ttm/ttm_resource.c
@@ -177,7 +177,7 @@ void ttm_resource_init(struct ttm_buffer_object *bo,
 	struct ttm_resource_manager *man;
 
 	res->start = 0;
-	res->num_pages = PFN_UP(bo->base.size);
+	res->size = bo->base.size;
 	res->mem_type = place->mem_type;
 	res->placement = place->flags;
 	res->bus.addr = NULL;
@@ -192,7 +192,7 @@ void ttm_resource_init(struct ttm_buffer_object *bo,
 		list_add_tail(&res->lru, &bo->bdev->pinned);
 	else
 		list_add_tail(&res->lru, &man->lru[bo->priority]);
-	man->usage += res->num_pages << PAGE_SHIFT;
+	man->usage += res->size;
 	spin_unlock(&bo->bdev->lru_lock);
 }
 EXPORT_SYMBOL(ttm_resource_init);
@@ -214,7 +214,7 @@ void ttm_resource_fini(struct ttm_resource_manager *man,
 
 	spin_lock(&bdev->lru_lock);
 	list_del_init(&res->lru);
-	man->usage -= res->num_pages << PAGE_SHIFT;
+	man->usage -= res->size;
 	spin_unlock(&bdev->lru_lock);
 }
 EXPORT_SYMBOL(ttm_resource_fini);
@@ -665,7 +665,7 @@ ttm_kmap_iter_linear_io_init(struct ttm_kmap_iter_linear_io *iter_io,
 		iosys_map_set_vaddr(&iter_io->dmap, mem->bus.addr);
 		iter_io->needs_unmap = false;
 	} else {
-		size_t bus_size = (size_t)mem->num_pages << PAGE_SHIFT;
+		size_t bus_size = (size_t)mem->size;
 
 		iter_io->needs_unmap = true;
 		memset(&iter_io->dmap, 0, sizeof(iter_io->dmap));
diff --git a/include/drm/ttm/ttm_resource.h b/include/drm/ttm/ttm_resource.h
index 5afc6d664fde..f93c9e52b063 100644
--- a/include/drm/ttm/ttm_resource.h
+++ b/include/drm/ttm/ttm_resource.h
@@ -208,7 +208,7 @@ struct ttm_bus_placement {
  */
 struct ttm_resource {
 	unsigned long start;
-	unsigned long num_pages;
+	size_t size;
 	uint32_t mem_type;
 	uint32_t placement;
 	struct ttm_bus_placement bus;
