[PATCH] uio: fix finding mm index for vma

[Hillf Danton]

When finding mm index for vma it looks more flexible that the mm could
be sparse, and
both the size of mm and the pgoff of vma could give correct selection.

Signed-off-by: Hillf Danton <dhillf@xxxxxxxxx>
---

--- a/drivers/uio/uio.c	2011-01-05 08:50:20.000000000 +0800
+++ b/drivers/uio/uio.c	2011-03-27 14:33:02.000000000 +0800
@@ -587,14 +587,12 @@ static ssize_t uio_write(struct file *fi

 static int uio_find_mem_index(struct vm_area_struct *vma)
 {
-	int mi;
 	struct uio_device *idev = vma->vm_private_data;

-	for (mi = 0; mi < MAX_UIO_MAPS; mi++) {
-		if (idev->info->mem[mi].size == 0)
+	if (vma->vm_pgoff < MAX_UIO_MAPS) {
+		if (idev->info->mem[vma->vm_pgoff].size == 0)
 			return -1;
-		if (vma->vm_pgoff == mi)
-			return mi;
+		return (int)vma->vm_pgoff;
 	}
 	return -1;
 }
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/