net: timestamp: add helper returning skb's tx tstamp

Add a helper function skb_get_tx_timestamp() that returns a tx timestamp
associated with an error queue skb.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/702357dd8936ef4c0d3864441e853bfe3224a677.1750065793.git.asml.silence@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/net/sock.h b/include/net/sock.h
index 92e7c1aae3ccafe3a806dcee07ec77a469c0f43d..f5f5a9ad290bf6e54201c512cfc6e530efc63024 100644 (file)
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2677,6 +2677,10 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
                             struct sk_buff *skb);
 
+bool skb_has_tx_timestamp(struct sk_buff *skb, const struct sock *sk);
+int skb_get_tx_timestamp(struct sk_buff *skb, struct sock *sk,
+                        struct timespec64 *ts);
+
 static inline void
 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
 {

diff --git a/net/socket.c b/net/socket.c
index 9a0e720f08598a4cbc7b99e71f6b9aabcf60ae84..2cab805943c0718c40ddea19fb72d58a9eac18ca 100644 (file)
--- a/net/socket.c
+++ b/net/socket.c
@@ -843,6 +843,52 @@ static void put_ts_pktinfo(struct msghdr *msg, struct sk_buff *skb,
                 sizeof(ts_pktinfo), &ts_pktinfo);
 }
 
+bool skb_has_tx_timestamp(struct sk_buff *skb, const struct sock *sk)
+{
+       const struct sock_exterr_skb *serr = SKB_EXT_ERR(skb);
+       u32 tsflags = READ_ONCE(sk->sk_tsflags);
+
+       if (serr->ee.ee_errno != ENOMSG ||
+          serr->ee.ee_origin != SO_EE_ORIGIN_TIMESTAMPING)
+               return false;
+
+       /* software time stamp available and wanted */
+       if ((tsflags & SOF_TIMESTAMPING_SOFTWARE) && skb->tstamp)
+               return true;
+       /* hardware time stamps available and wanted */
+       return (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
+               skb_hwtstamps(skb)->hwtstamp;
+}
+
+int skb_get_tx_timestamp(struct sk_buff *skb, struct sock *sk,
+                         struct timespec64 *ts)
+{
+       u32 tsflags = READ_ONCE(sk->sk_tsflags);
+       ktime_t hwtstamp;
+       int if_index = 0;
+
+       if ((tsflags & SOF_TIMESTAMPING_SOFTWARE) &&
+           ktime_to_timespec64_cond(skb->tstamp, ts))
+               return SOF_TIMESTAMPING_TX_SOFTWARE;
+
+       if (!(tsflags & SOF_TIMESTAMPING_RAW_HARDWARE) ||
+           skb_is_swtx_tstamp(skb, false))
+               return -ENOENT;
+
+       if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP_NETDEV)
+               hwtstamp = get_timestamp(sk, skb, &if_index);
+       else
+               hwtstamp = skb_hwtstamps(skb)->hwtstamp;
+
+       if (tsflags & SOF_TIMESTAMPING_BIND_PHC)
+               hwtstamp = ptp_convert_timestamp(&hwtstamp,
+                                               READ_ONCE(sk->sk_bind_phc));
+       if (!ktime_to_timespec64_cond(hwtstamp, ts))
+               return -ENOENT;
+
+       return SOF_TIMESTAMPING_TX_HARDWARE;
+}
+
 /*
  * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
  */