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>

3 files changed, 2 insertions, 6 deletions

diff --git a/net/can/af_can.c b/net/can/af_can.c
index 1684ba5b51eb..e8fd5dc1780a 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -89,13 +89,7 @@ static atomic_t skbcounter = ATOMIC_INIT(0);
 
 int can_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 {
-        struct sock *sk = sock->sk;
-
         switch (cmd) {
-
-        case SIOCGSTAMP:
-                return sock_get_timestamp(sk, (struct timeval __user *)arg);
-
         default:
                 return -ENOIOCTLCMD;
         }
diff --git a/net/can/bcm.c b/net/can/bcm.c
index 79bb8afa9c0c..a34ee52f19ea 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -1689,6 +1689,7 @@ static const struct proto_ops bcm_ops = {
         .getname       = sock_no_getname,
         .poll          = datagram_poll,
         .ioctl         = can_ioctl,     /* use can_ioctl() from af_can.c */
+        .gettstamp     = sock_gettstamp,
         .listen        = sock_no_listen,
         .shutdown      = sock_no_shutdown,
         .setsockopt    = sock_no_setsockopt,
diff --git a/net/can/raw.c b/net/can/raw.c
index c70207537488..afcbff063a67 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -846,6 +846,7 @@ static const struct proto_ops raw_ops = {
         .getname       = raw_getname,
         .poll          = datagram_poll,
         .ioctl         = can_ioctl,     /* use can_ioctl() from af_can.c */
+        .gettstamp     = sock_gettstamp,
         .listen        = sock_no_listen,
         .shutdown      = sock_no_shutdown,
         .setsockopt    = raw_setsockopt,