lguest: explicitly set miscdevice's private_data NULL
There is a proposed change to the miscdevice's behaviour on open(). Currently
file->private_data stays NULL, but only because we don't have an open-entry in
struct file_operations.
This may change so that private_data, more consistently, is always set to
struct miscdevice, not only *if* the driver has it's own open() routine and
fops-entry, see https://lkml.org/lkml/2014/12/4/939 and commit
94e4fe2cab3d43b3ba7c3f721743006a8c9d913a
In short: If we rely on file->private_data being NULL, we should ensure
it is NULL ourselves.
Signed-off-by: Martin Kepplinger <martink@posteo.de>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c
index c4c6113..30c6068 100644
--- a/drivers/lguest/lguest_user.c
+++ b/drivers/lguest/lguest_user.c
@@ -339,6 +339,13 @@
}
}
+static int open(struct inode *inode, struct file *file)
+{
+ file->private_data = NULL;
+
+ return 0;
+}
+
/*L:060
* The final piece of interface code is the close() routine. It reverses
* everything done in initialize(). This is usually called because the
@@ -409,6 +416,7 @@
*/
static const struct file_operations lguest_fops = {
.owner = THIS_MODULE,
+ .open = open,
.release = close,
.write = write,
.read = read,