[NET]: Add a dev_ioctl() fallback to sock_ioctl()

Currently all network protocols need to call dev_ioctl as the default
fallback in their ioctl implementations.  This patch adds a fallback
to dev_ioctl to sock_ioctl if the protocol returned -ENOIOCTLCMD.
This way all the procotol ioctl handlers can be simplified and we don't
need to export dev_ioctl.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 0 deletions

diff --git a/net/socket.c b/net/socket.c
index 0dde6dade2b1..06fa217f58a9 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -900,6 +900,13 @@ static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
                         break;
                 default:
                         err = sock->ops->ioctl(sock, cmd, arg);
+
+                        /*
+                         * If this ioctl is unknown try to hand it down
+                         * to the NIC driver.
+                         */
+                        if (err == -ENOIOCTLCMD)
+                                err = dev_ioctl(cmd, argp);
                         break;
         }
         return err;