diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
index bdf28f7..db122a0 100644
--- a/drivers/base/dma-coherent.c
+++ b/drivers/base/dma-coherent.c
@@ -261,7 +261,7 @@
 		   (mem->virt_base + (mem->size << PAGE_SHIFT))) {
 		unsigned long off = vma->vm_pgoff;
 		int start = (vaddr - mem->virt_base) >> PAGE_SHIFT;
-		int user_count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+		int user_count = vma_pages(vma);
 		int count = size >> PAGE_SHIFT;
 
 		*ret = -ENXIO;