net: rework SIOCGSTAMP ioctl handling

The SIOCGSTAMP/SIOCGSTAMPNS ioctl commands are implemented by many
socket protocol handlers, and all of those end up calling the same
sock_get_timestamp()/sock_get_timestampns() helper functions, which
results in a lot of duplicate code.

With the introduction of 64-bit time_t on 32-bit architectures, this
gets worse, as we then need four different ioctl commands in each
socket protocol implementation.

To simplify that, let's add a new .gettstamp() operation in
struct proto_ops, and move ioctl implementation into the common
sock_ioctl()/compat_sock_ioctl_trans() functions that these all go
through.

We can reuse the sock_get_timestamp() implementation, but generalize
it so it can deal with both native and compat mode, as well as
timeval and timespec structures.

Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/lkml/CAK8P3a038aDQQotzua_QtKGhq8O9n+rdiz2=WDCp82ys8eUT+A@mail.gmail.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
index 8d12198..94ddf19 100644
--- a/net/bluetooth/af_bluetooth.c
+++ b/net/bluetooth/af_bluetooth.c
@@ -521,14 +521,6 @@ int bt_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 		err = put_user(amount, (int __user *) arg);
 		break;
 
-	case SIOCGSTAMP:
-		err = sock_get_timestamp(sk, (struct timeval __user *) arg);
-		break;
-
-	case SIOCGSTAMPNS:
-		err = sock_get_timestampns(sk, (struct timespec __user *) arg);
-		break;
-
 	default:
 		err = -ENOIOCTLCMD;
 		break;
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index a3a2cd5..dcb14ab 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -1655,6 +1655,7 @@ static const struct proto_ops l2cap_sock_ops = {
 	.recvmsg	= l2cap_sock_recvmsg,
 	.poll		= bt_sock_poll,
 	.ioctl		= bt_sock_ioctl,
+	.gettstamp	= sock_gettstamp,
 	.mmap		= sock_no_mmap,
 	.socketpair	= sock_no_socketpair,
 	.shutdown	= l2cap_sock_shutdown,
diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index b1f49fc..90bb53a 100644
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -1039,6 +1039,7 @@ static const struct proto_ops rfcomm_sock_ops = {
 	.setsockopt	= rfcomm_sock_setsockopt,
 	.getsockopt	= rfcomm_sock_getsockopt,
 	.ioctl		= rfcomm_sock_ioctl,
+	.gettstamp	= sock_gettstamp,
 	.poll		= bt_sock_poll,
 	.socketpair	= sock_no_socketpair,
 	.mmap		= sock_no_mmap
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index d892b7c..b91d6b4 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -1190,6 +1190,7 @@ static const struct proto_ops sco_sock_ops = {
 	.recvmsg	= sco_sock_recvmsg,
 	.poll		= bt_sock_poll,
 	.ioctl		= bt_sock_ioctl,
+	.gettstamp	= sock_gettstamp,
 	.mmap		= sock_no_mmap,
 	.socketpair	= sock_no_socketpair,
 	.shutdown	= sco_sock_shutdown,