net: socket infrastructure for SO_TIMESTAMPING

The overlap with the old SO_TIMESTAMP[NS] options is handled so
that time stamping in software (net_enable_timestamp()) is
enabled when SO_TIMESTAMP[NS] and/or SO_TIMESTAMPING_RX_SOFTWARE
is set.  It's disabled if all of these are off.

Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 41 insertions, 3 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index ded6854e3e4a..cc9d5bcb06f7 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -158,7 +158,7 @@ struct sock_common {
   *     @sk_allocation: allocation mode
   *     @sk_sndbuf: size of send buffer in bytes
   *     @sk_flags: %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
-  *                %SO_OOBINLINE settings
+  *                %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
   *     @sk_no_check: %SO_NO_CHECK setting, wether or not checkup packets
   *     @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
   *     @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
@@ -488,6 +488,13 @@ enum sock_flags {
         SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
         SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
         SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
+        SOCK_TIMESTAMPING_TX_HARDWARE,  /* %SOF_TIMESTAMPING_TX_HARDWARE */
+        SOCK_TIMESTAMPING_TX_SOFTWARE,  /* %SOF_TIMESTAMPING_TX_SOFTWARE */
+        SOCK_TIMESTAMPING_RX_HARDWARE,  /* %SOF_TIMESTAMPING_RX_HARDWARE */
+        SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
+        SOCK_TIMESTAMPING_SOFTWARE,     /* %SOF_TIMESTAMPING_SOFTWARE */
+        SOCK_TIMESTAMPING_RAW_HARDWARE, /* %SOF_TIMESTAMPING_RAW_HARDWARE */
+        SOCK_TIMESTAMPING_SYS_HARDWARE, /* %SOF_TIMESTAMPING_SYS_HARDWARE */
 };
 
 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
@@ -1346,14 +1353,45 @@ static __inline__ void
 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
 {
         ktime_t kt = skb->tstamp;
+        struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
 
-        if (sock_flag(sk, SOCK_RCVTSTAMP))
+        /*
+         * generate control messages if
+         * - receive time stamping in software requested (SOCK_RCVTSTAMP
+         *   or SOCK_TIMESTAMPING_RX_SOFTWARE)
+         * - software time stamp available and wanted
+         *   (SOCK_TIMESTAMPING_SOFTWARE)
+         * - hardware time stamps available and wanted
+         *   (SOCK_TIMESTAMPING_SYS_HARDWARE or
+         *   SOCK_TIMESTAMPING_RAW_HARDWARE)
+         */
+        if (sock_flag(sk, SOCK_RCVTSTAMP) ||
+            sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE) ||
+            (kt.tv64 && sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) ||
+            (hwtstamps->hwtstamp.tv64 &&
+             sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) ||
+            (hwtstamps->syststamp.tv64 &&
+             sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)))
                 __sock_recv_timestamp(msg, sk, skb);
         else
                 sk->sk_stamp = kt;
 }
 
 /**
+ * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
+ * @msg:        outgoing packet
+ * @sk:         socket sending this packet
+ * @shtx:       filled with instructions for time stamping
+ *
+ * Currently only depends on SOCK_TIMESTAMPING* flags. Returns error code if
+ * parameters are invalid.
+ */
+extern int sock_tx_timestamp(struct msghdr *msg,
+                             struct sock *sk,
+                             union skb_shared_tx *shtx);
+
+
+/**
  * sk_eat_skb - Release a skb if it is no longer needed
  * @sk: socket to eat this skb from
  * @skb: socket buffer to eat
@@ -1421,7 +1459,7 @@ static inline struct sock *skb_steal_sock(struct sk_buff *skb)
         return NULL;
 }
 
-extern void sock_enable_timestamp(struct sock *sk);
+extern void sock_enable_timestamp(struct sock *sk, int flag);
 extern int sock_get_timestamp(struct sock *, struct timeval __user *);
 extern int sock_get_timestampns(struct sock *, struct timespec __user *);