net: sock: extend SO_TIMESTAMPING for PHC binding

Since PTP virtual clock support is added, there can be
several PTP virtual clocks based on one PTP physical
clock for timestamping.

This patch is to extend SO_TIMESTAMPING API to support
PHC (PTP Hardware Clock) binding by adding a new flag
SOF_TIMESTAMPING_BIND_PHC. When PTP virtual clocks are
in use, user space can configure to bind one for
timestamping, but PTP physical clock is not supported
and not needed to bind.

This patch is preparation for timestamp conversion from
raw timestamp to a specific PTP virtual clock time in
core net.

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 62 insertions, 3 deletions

diff --git a/net/core/sock.c b/net/core/sock.c
index dd9599656c40..cad107112204 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -139,6 +139,8 @@
 #include <net/tcp.h>
 #include <net/busy_poll.h>
 
+#include <linux/ethtool.h>
+
 static DEFINE_MUTEX(proto_list_mutex);
 static LIST_HEAD(proto_list);
 
@@ -810,8 +812,47 @@ void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
 	}
 }
 
-int sock_set_timestamping(struct sock *sk, int optname, int val)
+static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
 {
+	struct net *net = sock_net(sk);
+	struct net_device *dev = NULL;
+	bool match = false;
+	int *vclock_index;
+	int i, num;
+
+	if (sk->sk_bound_dev_if)
+		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
+
+	if (!dev) {
+		pr_err("%s: sock not bind to device\n", __func__);
+		return -EOPNOTSUPP;
+	}
+
+	num = ethtool_get_phc_vclocks(dev, &vclock_index);
+	for (i = 0; i < num; i++) {
+		if (*(vclock_index + i) == phc_index) {
+			match = true;
+			break;
+		}
+	}
+
+	if (num > 0)
+		kfree(vclock_index);
+
+	if (!match)
+		return -EINVAL;
+
+	sk->sk_bind_phc = phc_index;
+
+	return 0;
+}
+
+int sock_set_timestamping(struct sock *sk, int optname,
+			  struct so_timestamping timestamping)
+{
+	int val = timestamping.flags;
+	int ret;
+
 	if (val & ~SOF_TIMESTAMPING_MASK)
 		return -EINVAL;
 
@@ -832,6 +873,12 @@ int sock_set_timestamping(struct sock *sk, int optname, int val)
 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
 		return -EINVAL;
 
+	if (val & SOF_TIMESTAMPING_BIND_PHC) {
+		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
+		if (ret)
+			return ret;
+	}
+
 	sk->sk_tsflags = val;
 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
 
@@ -907,6 +954,7 @@ EXPORT_SYMBOL(sock_set_mark);
 int sock_setsockopt(struct socket *sock, int level, int optname,
 		    sockptr_t optval, unsigned int optlen)
 {
+	struct so_timestamping timestamping;
 	struct sock_txtime sk_txtime;
 	struct sock *sk = sock->sk;
 	int val;
@@ -1073,7 +1121,15 @@ set_sndbuf:
 
 	case SO_TIMESTAMPING_NEW:
 	case SO_TIMESTAMPING_OLD:
-		ret = sock_set_timestamping(sk, optname, val);
+		if (optlen == sizeof(timestamping)) {
+			if (copy_from_sockptr(&timestamping, optval,
+					      sizeof(timestamping)))
+				return -EFAULT;
+		} else {
+			memset(&timestamping, 0, sizeof(timestamping));
+			timestamping.flags = val;
+		}
+		ret = sock_set_timestamping(sk, optname, timestamping);
 		break;
 
 	case SO_RCVLOWAT:
@@ -1348,6 +1404,7 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
 		struct __kernel_old_timeval tm;
 		struct  __kernel_sock_timeval stm;
 		struct sock_txtime txtime;
+		struct so_timestamping timestamping;
 	} v;
 
 	int lv = sizeof(int);
@@ -1451,7 +1508,9 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
 		break;
 
 	case SO_TIMESTAMPING_OLD:
-		v.val = sk->sk_tsflags;
+		lv = sizeof(v.timestamping);
+		v.timestamping.flags = sk->sk_tsflags;
+		v.timestamping.bind_phc = sk->sk_bind_phc;
 		break;
 
 	case SO_RCVTIMEO_OLD: