[PATCH] xen/gntdev: use vma_pages().

[Muhammad Falak R Wani]

Replace explicit computation of vma page count by a call to
vma_pages()

Signed-off-by: Muhammad Falak R Wani <falakreyaz@xxxxxxxxx>
---
 drivers/xen/gntdev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index 6793957..bb95212 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -982,7 +982,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
 {
 	struct gntdev_priv *priv = flip->private_data;
 	int index = vma->vm_pgoff;
-	int count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+	int count = vma_pages(vma);
 	struct grant_map *map;
 	int i, err = -EINVAL;
 
-- 
1.9.1