[PATCH] xen/gntalloc: 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/gntalloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c
index 4547a91..7a47c4c 100644
--- a/drivers/xen/gntalloc.c
+++ b/drivers/xen/gntalloc.c
@@ -504,7 +504,7 @@ static int gntalloc_mmap(struct file *filp, struct vm_area_struct *vma)
 	struct gntalloc_file_private_data *priv = filp->private_data;
 	struct gntalloc_vma_private_data *vm_priv;
 	struct gntalloc_gref *gref;
-	int count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+	int count = vma_pages(vma);
 	int rv, i;
 
 	if (!(vma->vm_flags & VM_SHARED)) {
-- 
1.9.1