uio: use vma_pages() to replace (vm_end - vm_start) >> PAGE_SHIFT

(*->vm_end - *->vm_start) >> PAGE_SHIFT operation is implemented
as a inline funcion vma_pages() in linux/mm.h, so using it.

Signed-off-by: Libin <huawei.libin@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index b645c47..3b96f18 100644 (file)
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -677,7 +677,7 @@ static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
        if (mi < 0)
                return -EINVAL;
 
-       requested_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+       requested_pages = vma_pages(vma);
        actual_pages = ((idev->info->mem[mi].addr & ~PAGE_MASK)
                        + idev->info->mem[mi].size + PAGE_SIZE -1) >> PAGE_SHIFT;
        if (requested_pages > actual_pages)