[PATCH net-next v5 0/3] Add option to provide OPT_ID value via cmsg

[PATCH net-next v5 0/3] Add option to provide OPT_ID value via cmsg

[Vadim Fedorenko]

SOF_TIMESTAMPING_OPT_ID socket option flag gives a way to correlate TX
timestamps and packets sent via socket. Unfortunately, there is no way
to reliably predict socket timestamp ID value in case of error returned
by sendmsg. For UDP sockets it's impossible because of lockless
nature of UDP transmit, several threads may send packets in parallel. In
case of RAW sockets MSG_MORE option makes things complicated. More
details are in the conversation [1].
This patch adds new control message type to give user-space
software an opportunity to control the mapping between packets and
values by providing ID with each sendmsg.

The first patch in the series adds all needed definitions and implements
the function for UDP sockets. The explicit check of socket's type is not
added because subsequent patches in the series will add support for other
types of sockets. The documentation is also included into the first
patch.

Patch 2/4 adds support for TCP sockets. This part is simple and straight
forward.

Patch 3/4 adds support for RAW sockets. It's a bit tricky because
sock_tx_timestamp functions has to be refactored to receive full socket
cookie information to fill in ID. The commit b534dc46c8ae ("net_tstamp:
add SOF_TIMESTAMPING_OPT_ID_TCP") did the conversion of sk_tsflags to
u32 but sock_tx_timestamp functions were not converted and still receive
16b flags. It wasn't a problem because SOF_TIMESTAMPING_OPT_ID_TCP was
not checked in these functions, that's why no backporting is needed.

Patch 4/4 adds selftests for new feature.

Changelog:
v4 -> v5:
- replace BUILD_BUG_ON_MSG with simple BUILD_BUG_ON
- adjust comment about added flag and check
- remove redefinition of flag from selftests
- adjust tcp_tx_timestamp() to use sock cookie 
v3 -> v4:
- remove static_assert from UAPI header
- add BUILD_BUG_ON_MSG with some explanation
- use SOF_TIMESTAMPING_OPT_ID flag in ipv4/ipv6 UDP case
- move ts_opt_id initialization under flag check to avoid extra
  assignment in the hot path
v2 -> v3:
- remove SOF_TIMESTAMPING_OPT_ID_CMSG UAPI value and use kernel-internal
  SOCKCM_FLAG_TS_OPT_ID which uses the highest bit of tsflags.
- add support for TCP and RAW sockets
v1 -> v2:
- add more selftests
- add documentation for the feature
- refactor UDP send function
RFC -> v1:
- add selftests
- add SOF_TIMESTAMPING_OPT_ID_CMSG to signal of custom ID provided by
	user-space instead of reserving value of 0 for this.

[1] https://lore.kernel.org/netdev/CALCETrU0jB+kg0mhV6A8mrHfTE1D1pr1SD_B9Eaa9aDPfgHdtA@mail.gmail.com/

Vadim Fedorenko (3):
  net_tstamp: add SCM_TS_OPT_ID to provide OPT_ID in control message
  net_tstamp: add SCM_TS_OPT_ID for RAW sockets
  selftests: txtimestamp: add SCM_TS_OPT_ID test

 Documentation/networking/timestamping.rst  | 14 +++++++
 arch/alpha/include/uapi/asm/socket.h       |  2 +
 arch/mips/include/uapi/asm/socket.h        |  2 +
 arch/parisc/include/uapi/asm/socket.h      |  2 +
 arch/sparc/include/uapi/asm/socket.h       |  2 +
 include/net/inet_sock.h                    |  4 +-
 include/net/sock.h                         | 34 ++++++++++++-----
 include/uapi/asm-generic/socket.h          |  2 +
 net/can/raw.c                              |  2 +-
 net/core/sock.c                            | 13 +++++++
 net/ipv4/ip_output.c                       | 21 ++++++++---
 net/ipv4/raw.c                             |  2 +-
 net/ipv4/tcp.c                             |  7 ++--
 net/ipv6/ip6_output.c                      | 22 +++++++----
 net/ipv6/raw.c                             |  2 +-
 net/packet/af_packet.c                     |  6 +--
 net/socket.c                               |  2 +-
 tools/include/uapi/asm-generic/socket.h    |  2 +
 tools/testing/selftests/net/txtimestamp.c  | 44 +++++++++++++++++-----
 tools/testing/selftests/net/txtimestamp.sh | 12 +++---
 20 files changed, 149 insertions(+), 48 deletions(-)

-- 
2.43.5

[PATCH net-next v5 1/3] net_tstamp: add SCM_TS_OPT_ID to provide OPT_ID in control message

[Vadim Fedorenko]

SOF_TIMESTAMPING_OPT_ID socket option flag gives a way to correlate TX
timestamps and packets sent via socket. Unfortunately, there is no way
to reliably predict socket timestamp ID value in case of error returned
by sendmsg. For UDP sockets it's impossible because of lockless
nature of UDP transmit, several threads may send packets in parallel. In
case of RAW sockets MSG_MORE option makes things complicated. More
details are in the conversation [1].
This patch adds new control message type to give user-space
software an opportunity to control the mapping between packets and
values by providing ID with each sendmsg for UDP sockets.
The documentation is also added in this patch.

[1] https://lore.kernel.org/netdev/CALCETrU0jB+kg0mhV6A8mrHfTE1D1pr1SD_B9Eaa9aDPfgHdtA@mail.gmail.com/

Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
---
 Documentation/networking/timestamping.rst | 14 ++++++++++++++
 arch/alpha/include/uapi/asm/socket.h      |  2 ++
 arch/mips/include/uapi/asm/socket.h       |  2 ++
 arch/parisc/include/uapi/asm/socket.h     |  2 ++
 arch/sparc/include/uapi/asm/socket.h      |  2 ++
 include/net/inet_sock.h                   |  4 +++-
 include/net/sock.h                        |  7 +++++++
 include/uapi/asm-generic/socket.h         |  2 ++
 net/core/sock.c                           | 13 +++++++++++++
 net/ipv4/ip_output.c                      | 19 ++++++++++++++-----
 net/ipv6/ip6_output.c                     | 20 ++++++++++++++------
 11 files changed, 75 insertions(+), 12 deletions(-)

diff --git a/Documentation/networking/timestamping.rst b/Documentation/networking/timestamping.rst
index 8199e6917671..b37bfbfc7d79 100644
--- a/Documentation/networking/timestamping.rst
+++ b/Documentation/networking/timestamping.rst
@@ -194,6 +194,20 @@ SOF_TIMESTAMPING_OPT_ID:
   among all possibly concurrently outstanding timestamp requests for
   that socket.
 
+  The process can optionally override the default generated ID, by
+  passing a specific ID with control message SCM_TS_OPT_ID (not
+  supported for TCP sockets)::
+
+    struct msghdr *msg;
+    ...
+    cmsg			 = CMSG_FIRSTHDR(msg);
+    cmsg->cmsg_level		 = SOL_SOCKET;
+    cmsg->cmsg_type		 = SCM_TS_OPT_ID;
+    cmsg->cmsg_len		 = CMSG_LEN(sizeof(__u32));
+    *((__u32 *) CMSG_DATA(cmsg)) = opt_id;
+    err = sendmsg(fd, msg, 0);
+
+
 SOF_TIMESTAMPING_OPT_ID_TCP:
   Pass this modifier along with SOF_TIMESTAMPING_OPT_ID for new TCP
   timestamping applications. SOF_TIMESTAMPING_OPT_ID defines how the
diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h
index e94f621903fe..99dec81e7c84 100644
--- a/arch/alpha/include/uapi/asm/socket.h
+++ b/arch/alpha/include/uapi/asm/socket.h
@@ -140,6 +140,8 @@
 #define SO_PASSPIDFD		76
 #define SO_PEERPIDFD		77
 
+#define SCM_TS_OPT_ID		78
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64
diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h
index 60ebaed28a4c..bb3dc8feb205 100644
--- a/arch/mips/include/uapi/asm/socket.h
+++ b/arch/mips/include/uapi/asm/socket.h
@@ -151,6 +151,8 @@
 #define SO_PASSPIDFD		76
 #define SO_PEERPIDFD		77
 
+#define SCM_TS_OPT_ID		78
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64
diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h
index be264c2b1a11..c3ab3b3289eb 100644
--- a/arch/parisc/include/uapi/asm/socket.h
+++ b/arch/parisc/include/uapi/asm/socket.h
@@ -132,6 +132,8 @@
 #define SO_PASSPIDFD		0x404A
 #define SO_PEERPIDFD		0x404B
 
+#define SCM_TS_OPT_ID		0x404C
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64
diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h
index 682da3714686..9b40f0a57fbc 100644
--- a/arch/sparc/include/uapi/asm/socket.h
+++ b/arch/sparc/include/uapi/asm/socket.h
@@ -133,6 +133,8 @@
 #define SO_PASSPIDFD             0x0055
 #define SO_PEERPIDFD             0x0056
 
+#define SCM_TS_OPT_ID            0x0057
+
 #if !defined(__KERNEL__)
 
 
diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 394c3b66065e..f01dd273bea6 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -174,6 +174,7 @@ struct inet_cork {
 	__s16			tos;
 	char			priority;
 	__u16			gso_size;
+	u32			ts_opt_id;
 	u64			transmit_time;
 	u32			mark;
 };
@@ -241,7 +242,8 @@ struct inet_sock {
 	struct inet_cork_full	cork;
 };
 
-#define IPCORK_OPT	1	/* ip-options has been held in ipcork.opt */
+#define IPCORK_OPT		1	/* ip-options has been held in ipcork.opt */
+#define IPCORK_TS_OPT_ID	2	/* ts_opt_id field is valid, overriding sk_tskey */
 
 enum {
 	INET_FLAGS_PKTINFO	= 0,
diff --git a/include/net/sock.h b/include/net/sock.h
index f51d61fab059..a2738cfd4804 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -952,6 +952,12 @@ enum sock_flags {
 };
 
 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
+/*
+ * The highest bit of sk_tsflags is reserved for kernel-internal
+ * SOCKCM_FLAG_TS_OPT_ID. There is a check in core/sock.c to control that
+ * SOF_TIMESTAMPING* values do not reach this reserved area
+ */
+#define SOCKCM_FLAG_TS_OPT_ID	BIT(31)
 
 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk)
 {
@@ -1794,6 +1800,7 @@ struct sockcm_cookie {
 	u64 transmit_time;
 	u32 mark;
 	u32 tsflags;
+	u32 ts_opt_id;
 };
 
 static inline void sockcm_init(struct sockcm_cookie *sockc,
diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
index 8ce8a39a1e5f..db3df3e74b01 100644
--- a/include/uapi/asm-generic/socket.h
+++ b/include/uapi/asm-generic/socket.h
@@ -135,6 +135,8 @@
 #define SO_PASSPIDFD		76
 #define SO_PEERPIDFD		77
 
+#define SCM_TS_OPT_ID		78
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__))
diff --git a/net/core/sock.c b/net/core/sock.c
index 468b1239606c..4b694a5a3d5d 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2831,6 +2831,8 @@ int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
 {
 	u32 tsflags;
 
+	BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
+
 	switch (cmsg->cmsg_type) {
 	case SO_MARK:
 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
@@ -2859,6 +2861,17 @@ int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
 			return -EINVAL;
 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
 		break;
+	case SCM_TS_OPT_ID:
+		if (sk_is_tcp(sk))
+			return -EINVAL;
+		tsflags = READ_ONCE(sk->sk_tsflags);
+		if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
+			return -EINVAL;
+		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
+			return -EINVAL;
+		sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
+		sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
+		break;
 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
 	case SCM_RIGHTS:
 	case SCM_CREDENTIALS:
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 49811c9281d4..0c7049f50369 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -973,7 +973,7 @@ static int __ip_append_data(struct sock *sk,
 	unsigned int maxfraglen, fragheaderlen, maxnonfragsize;
 	int csummode = CHECKSUM_NONE;
 	struct rtable *rt = dst_rtable(cork->dst);
-	bool paged, hold_tskey, extra_uref = false;
+	bool paged, hold_tskey = false, extra_uref = false;
 	unsigned int wmem_alloc_delta = 0;
 	u32 tskey = 0;
 
@@ -1049,10 +1049,15 @@ static int __ip_append_data(struct sock *sk,
 
 	cork->length += length;
 
-	hold_tskey = cork->tx_flags & SKBTX_ANY_TSTAMP &&
-		     READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_OPT_ID;
-	if (hold_tskey)
-		tskey = atomic_inc_return(&sk->sk_tskey) - 1;
+	if (cork->tx_flags & SKBTX_ANY_TSTAMP &&
+	    READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_OPT_ID) {
+		if (cork->flags & IPCORK_TS_OPT_ID) {
+			tskey = cork->ts_opt_id;
+		} else {
+			tskey = atomic_inc_return(&sk->sk_tskey) - 1;
+			hold_tskey = true;
+		}
+	}
 
 	/* So, what's going on in the loop below?
 	 *
@@ -1327,6 +1332,10 @@ static int ip_setup_cork(struct sock *sk, struct inet_cork *cork,
 	cork->transmit_time = ipc->sockc.transmit_time;
 	cork->tx_flags = 0;
 	sock_tx_timestamp(sk, ipc->sockc.tsflags, &cork->tx_flags);
+	if (ipc->sockc.tsflags & SOCKCM_FLAG_TS_OPT_ID) {
+		cork->flags |= IPCORK_TS_OPT_ID;
+		cork->ts_opt_id = ipc->sockc.ts_opt_id;
+	}
 
 	return 0;
 }
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index f26841f1490f..ff6bd8d85e9a 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1402,7 +1402,10 @@ static int ip6_setup_cork(struct sock *sk, struct inet_cork_full *cork,
 	cork->base.tx_flags = 0;
 	cork->base.mark = ipc6->sockc.mark;
 	sock_tx_timestamp(sk, ipc6->sockc.tsflags, &cork->base.tx_flags);
-
+	if (ipc6->sockc.tsflags & SOCKCM_FLAG_TS_OPT_ID) {
+		cork->base.flags |= IPCORK_TS_OPT_ID;
+		cork->base.ts_opt_id = ipc6->sockc.ts_opt_id;
+	}
 	cork->base.length = 0;
 	cork->base.transmit_time = ipc6->sockc.transmit_time;
 
@@ -1433,7 +1436,7 @@ static int __ip6_append_data(struct sock *sk,
 	bool zc = false;
 	u32 tskey = 0;
 	struct rt6_info *rt = dst_rt6_info(cork->dst);
-	bool paged, hold_tskey, extra_uref = false;
+	bool paged, hold_tskey = false, extra_uref = false;
 	struct ipv6_txoptions *opt = v6_cork->opt;
 	int csummode = CHECKSUM_NONE;
 	unsigned int maxnonfragsize, headersize;
@@ -1543,10 +1546,15 @@ static int __ip6_append_data(struct sock *sk,
 			flags &= ~MSG_SPLICE_PAGES;
 	}
 
-	hold_tskey = cork->tx_flags & SKBTX_ANY_TSTAMP &&
-		     READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_OPT_ID;
-	if (hold_tskey)
-		tskey = atomic_inc_return(&sk->sk_tskey) - 1;
+	if (cork->tx_flags & SKBTX_ANY_TSTAMP &&
+	    READ_ONCE(sk->sk_tsflags) & SOF_TIMESTAMPING_OPT_ID) {
+		if (cork->flags & IPCORK_TS_OPT_ID) {
+			tskey = cork->ts_opt_id;
+		} else {
+			tskey = atomic_inc_return(&sk->sk_tskey) - 1;
+			hold_tskey = true;
+		}
+	}
 
 	/*
 	 * Let's try using as much space as possible.
-- 
2.43.5

[PATCH net-next v5 2/3] net_tstamp: add SCM_TS_OPT_ID for RAW sockets

[Vadim Fedorenko]

The last type of sockets which supports SOF_TIMESTAMPING_OPT_ID is RAW
sockets. To add new option this patch converts all callers (direct and
indirect) of _sock_tx_timestamp to provide sockcm_cookie instead of
tsflags. And while here fix __sock_tx_timestamp to receive tsflags as
__u32 instead of __u16.

Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
---
 include/net/sock.h     | 27 ++++++++++++++++++---------
 net/can/raw.c          |  2 +-
 net/ipv4/ip_output.c   |  2 +-
 net/ipv4/raw.c         |  2 +-
 net/ipv4/tcp.c         |  7 ++++---
 net/ipv6/ip6_output.c  |  2 +-
 net/ipv6/raw.c         |  2 +-
 net/packet/af_packet.c |  6 +++---
 net/socket.c           |  2 +-
 9 files changed, 31 insertions(+), 21 deletions(-)

diff --git a/include/net/sock.h b/include/net/sock.h
index a2738cfd4804..e5ded32b4801 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2658,39 +2658,48 @@ static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
 		sock_write_timestamp(sk, 0);
 }
 
-void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
+void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags);
 
 /**
  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
  * @sk:		socket sending this packet
- * @tsflags:	timestamping flags to use
+ * @sockc:	pointer to socket cmsg cookie to get timestamping info
  * @tx_flags:	completed with instructions for time stamping
  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
  *
  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
  */
-static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
+static inline void _sock_tx_timestamp(struct sock *sk,
+				      const struct sockcm_cookie *sockc,
 				      __u8 *tx_flags, __u32 *tskey)
 {
+	__u32 tsflags = sockc->tsflags;
+
 	if (unlikely(tsflags)) {
 		__sock_tx_timestamp(tsflags, tx_flags);
 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
-		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
-			*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
+		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) {
+			if (tsflags & SOCKCM_FLAG_TS_OPT_ID)
+				*tskey = sockc->ts_opt_id;
+			else
+				*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
+		}
 	}
 	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
 		*tx_flags |= SKBTX_WIFI_STATUS;
 }
 
-static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
+static inline void sock_tx_timestamp(struct sock *sk,
+				     const struct sockcm_cookie *sockc,
 				     __u8 *tx_flags)
 {
-	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
+	_sock_tx_timestamp(sk, sockc, tx_flags, NULL);
 }
 
-static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
+static inline void skb_setup_tx_timestamp(struct sk_buff *skb,
+					  const struct sockcm_cookie *sockc)
 {
-	_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
+	_sock_tx_timestamp(skb->sk, sockc, &skb_shinfo(skb)->tx_flags,
 			   &skb_shinfo(skb)->tskey);
 }
 
diff --git a/net/can/raw.c b/net/can/raw.c
index 00533f64d69d..255c0a8f39d6 100644
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -966,7 +966,7 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	skb->mark = READ_ONCE(sk->sk_mark);
 	skb->tstamp = sockc.transmit_time;
 
-	skb_setup_tx_timestamp(skb, sockc.tsflags);
+	skb_setup_tx_timestamp(skb, &sockc);
 
 	err = can_send(skb, ro->loopback);
 
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 0c7049f50369..e5c55a95063d 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -1331,7 +1331,7 @@ static int ip_setup_cork(struct sock *sk, struct inet_cork *cork,
 	cork->priority = ipc->priority;
 	cork->transmit_time = ipc->sockc.transmit_time;
 	cork->tx_flags = 0;
-	sock_tx_timestamp(sk, ipc->sockc.tsflags, &cork->tx_flags);
+	sock_tx_timestamp(sk, &ipc->sockc, &cork->tx_flags);
 	if (ipc->sockc.tsflags & SOCKCM_FLAG_TS_OPT_ID) {
 		cork->flags |= IPCORK_TS_OPT_ID;
 		cork->ts_opt_id = ipc->sockc.ts_opt_id;
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 474dfd263c8b..0e9e01967ec9 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -370,7 +370,7 @@ static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
 
 	skb->ip_summed = CHECKSUM_NONE;
 
-	skb_setup_tx_timestamp(skb, sockc->tsflags);
+	skb_setup_tx_timestamp(skb, sockc);
 
 	if (flags & MSG_CONFIRM)
 		skb_set_dst_pending_confirm(skb, 1);
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index e359a9161445..62f31d6b4659 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -474,15 +474,16 @@ void tcp_init_sock(struct sock *sk)
 }
 EXPORT_SYMBOL(tcp_init_sock);
 
-static void tcp_tx_timestamp(struct sock *sk, u16 tsflags)
+static void tcp_tx_timestamp(struct sock *sk, struct sockcm_cookie *sockc)
 {
 	struct sk_buff *skb = tcp_write_queue_tail(sk);
+	u32 tsflags = sockc->tsflags;
 
 	if (tsflags && skb) {
 		struct skb_shared_info *shinfo = skb_shinfo(skb);
 		struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
 
-		sock_tx_timestamp(sk, tsflags, &shinfo->tx_flags);
+		sock_tx_timestamp(sk, sockc, &shinfo->tx_flags);
 		if (tsflags & SOF_TIMESTAMPING_TX_ACK)
 			tcb->txstamp_ack = 1;
 		if (tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
@@ -1318,7 +1319,7 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size)
 
 out:
 	if (copied) {
-		tcp_tx_timestamp(sk, sockc.tsflags);
+		tcp_tx_timestamp(sk, &sockc);
 		tcp_push(sk, flags, mss_now, tp->nonagle, size_goal);
 	}
 out_nopush:
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index ff6bd8d85e9a..205673179b3c 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1401,7 +1401,7 @@ static int ip6_setup_cork(struct sock *sk, struct inet_cork_full *cork,
 	cork->base.gso_size = ipc6->gso_size;
 	cork->base.tx_flags = 0;
 	cork->base.mark = ipc6->sockc.mark;
-	sock_tx_timestamp(sk, ipc6->sockc.tsflags, &cork->base.tx_flags);
+	sock_tx_timestamp(sk, &ipc6->sockc, &cork->base.tx_flags);
 	if (ipc6->sockc.tsflags & SOCKCM_FLAG_TS_OPT_ID) {
 		cork->base.flags |= IPCORK_TS_OPT_ID;
 		cork->base.ts_opt_id = ipc6->sockc.ts_opt_id;
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 608fa9d05b55..8476a3944a88 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -629,7 +629,7 @@ static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
 
 	skb->ip_summed = CHECKSUM_NONE;
 
-	skb_setup_tx_timestamp(skb, sockc->tsflags);
+	skb_setup_tx_timestamp(skb, sockc);
 
 	if (flags & MSG_CONFIRM)
 		skb_set_dst_pending_confirm(skb, 1);
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 4a364cdd445e..83ef86c0dd88 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -2118,7 +2118,7 @@ static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
 	skb->priority = READ_ONCE(sk->sk_priority);
 	skb->mark = READ_ONCE(sk->sk_mark);
 	skb_set_delivery_type_by_clockid(skb, sockc.transmit_time, sk->sk_clockid);
-	skb_setup_tx_timestamp(skb, sockc.tsflags);
+	skb_setup_tx_timestamp(skb, &sockc);
 
 	if (unlikely(extra_len == 4))
 		skb->no_fcs = 1;
@@ -2650,7 +2650,7 @@ static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
 	skb->priority = READ_ONCE(po->sk.sk_priority);
 	skb->mark = READ_ONCE(po->sk.sk_mark);
 	skb_set_delivery_type_by_clockid(skb, sockc->transmit_time, po->sk.sk_clockid);
-	skb_setup_tx_timestamp(skb, sockc->tsflags);
+	skb_setup_tx_timestamp(skb, sockc);
 	skb_zcopy_set_nouarg(skb, ph.raw);
 
 	skb_reserve(skb, hlen);
@@ -3115,7 +3115,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
 		goto out_free;
 	}
 
-	skb_setup_tx_timestamp(skb, sockc.tsflags);
+	skb_setup_tx_timestamp(skb, &sockc);
 
 	if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
 	    !packet_extra_vlan_len_allowed(dev, skb)) {
diff --git a/net/socket.c b/net/socket.c
index 8d8b84fa404a..25bb8c0f7e57 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -688,7 +688,7 @@ void sock_release(struct socket *sock)
 }
 EXPORT_SYMBOL(sock_release);
 
-void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags)
+void __sock_tx_timestamp(__u32 tsflags, __u8 *tx_flags)
 {
 	u8 flags = *tx_flags;
 
-- 
2.43.5

[PATCH net-next v5 3/3] selftests: txtimestamp: add SCM_TS_OPT_ID test

[Vadim Fedorenko]

Extend txtimestamp test to run with fixed tskey using
SCM_TS_OPT_ID control message for all types of sockets.

Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Vadim Fedorenko <vadfed@meta.com>
---
 tools/include/uapi/asm-generic/socket.h    |  2 +
 tools/testing/selftests/net/txtimestamp.c  | 44 +++++++++++++++++-----
 tools/testing/selftests/net/txtimestamp.sh | 12 +++---
 3 files changed, 43 insertions(+), 15 deletions(-)

diff --git a/tools/include/uapi/asm-generic/socket.h b/tools/include/uapi/asm-generic/socket.h
index 54d9c8bf7c55..281df9139d2b 100644
--- a/tools/include/uapi/asm-generic/socket.h
+++ b/tools/include/uapi/asm-generic/socket.h
@@ -124,6 +124,8 @@
 #define SO_PASSPIDFD		76
 #define SO_PEERPIDFD		77
 
+#define SCM_TS_OPT_ID		78
+
 #if !defined(__KERNEL__)
 
 #if __BITS_PER_LONG == 64 || (defined(__x86_64__) && defined(__ILP32__))
diff --git a/tools/testing/selftests/net/txtimestamp.c b/tools/testing/selftests/net/txtimestamp.c
index d626f22f9550..dae91eb97d69 100644
--- a/tools/testing/selftests/net/txtimestamp.c
+++ b/tools/testing/selftests/net/txtimestamp.c
@@ -77,6 +77,8 @@ static bool cfg_epollet;
 static bool cfg_do_listen;
 static uint16_t dest_port = 9000;
 static bool cfg_print_nsec;
+static uint32_t ts_opt_id;
+static bool cfg_use_cmsg_opt_id;
 
 static struct sockaddr_in daddr;
 static struct sockaddr_in6 daddr6;
@@ -136,12 +138,13 @@ static void validate_key(int tskey, int tstype)
 	/* compare key for each subsequent request
 	 * must only test for one type, the first one requested
 	 */
-	if (saved_tskey == -1)
+	if (saved_tskey == -1 || cfg_use_cmsg_opt_id)
 		saved_tskey_type = tstype;
 	else if (saved_tskey_type != tstype)
 		return;
 
 	stepsize = cfg_proto == SOCK_STREAM ? cfg_payload_len : 1;
+	stepsize = cfg_use_cmsg_opt_id ? 0 : stepsize;
 	if (tskey != saved_tskey + stepsize) {
 		fprintf(stderr, "ERROR: key %d, expected %d\n",
 				tskey, saved_tskey + stepsize);
@@ -484,7 +487,7 @@ static void fill_header_udp(void *p, bool is_ipv4)
 
 static void do_test(int family, unsigned int report_opt)
 {
-	char control[CMSG_SPACE(sizeof(uint32_t))];
+	char control[2 * CMSG_SPACE(sizeof(uint32_t))];
 	struct sockaddr_ll laddr;
 	unsigned int sock_opt;
 	struct cmsghdr *cmsg;
@@ -624,18 +627,32 @@ static void do_test(int family, unsigned int report_opt)
 		msg.msg_iov = &iov;
 		msg.msg_iovlen = 1;
 
-		if (cfg_use_cmsg) {
+		if (cfg_use_cmsg || cfg_use_cmsg_opt_id) {
 			memset(control, 0, sizeof(control));
 
 			msg.msg_control = control;
-			msg.msg_controllen = sizeof(control);
+			msg.msg_controllen = cfg_use_cmsg * CMSG_SPACE(sizeof(uint32_t));
+			msg.msg_controllen += cfg_use_cmsg_opt_id * CMSG_SPACE(sizeof(uint32_t));
 
-			cmsg = CMSG_FIRSTHDR(&msg);
-			cmsg->cmsg_level = SOL_SOCKET;
-			cmsg->cmsg_type = SO_TIMESTAMPING;
-			cmsg->cmsg_len = CMSG_LEN(sizeof(uint32_t));
+			cmsg = NULL;
+			if (cfg_use_cmsg) {
+				cmsg = CMSG_FIRSTHDR(&msg);
+				cmsg->cmsg_level = SOL_SOCKET;
+				cmsg->cmsg_type = SO_TIMESTAMPING;
+				cmsg->cmsg_len = CMSG_LEN(sizeof(uint32_t));
+
+				*((uint32_t *)CMSG_DATA(cmsg)) = report_opt;
+			}
+			if (cfg_use_cmsg_opt_id) {
+				cmsg = cmsg ? CMSG_NXTHDR(&msg, cmsg) : CMSG_FIRSTHDR(&msg);
+				cmsg->cmsg_level = SOL_SOCKET;
+				cmsg->cmsg_type = SCM_TS_OPT_ID;
+				cmsg->cmsg_len = CMSG_LEN(sizeof(uint32_t));
+
+				*((uint32_t *)CMSG_DATA(cmsg)) = ts_opt_id;
+				saved_tskey = ts_opt_id;
+			}
 
-			*((uint32_t *) CMSG_DATA(cmsg)) = report_opt;
 		}
 
 		val = sendmsg(fd, &msg, 0);
@@ -685,6 +702,7 @@ static void __attribute__((noreturn)) usage(const char *filepath)
 			"  -L    listen on hostname and port\n"
 			"  -n:   set no-payload option\n"
 			"  -N:   print timestamps and durations in nsec (instead of usec)\n"
+			"  -o N: use SCM_TS_OPT_ID control message to provide N as tskey\n"
 			"  -p N: connect to port N\n"
 			"  -P:   use PF_PACKET\n"
 			"  -r:   use raw\n"
@@ -705,7 +723,7 @@ static void parse_opt(int argc, char **argv)
 	int c;
 
 	while ((c = getopt(argc, argv,
-				"46bc:CeEFhIl:LnNp:PrRS:t:uv:V:x")) != -1) {
+				"46bc:CeEFhIl:LnNo:p:PrRS:t:uv:V:x")) != -1) {
 		switch (c) {
 		case '4':
 			do_ipv6 = 0;
@@ -746,6 +764,10 @@ static void parse_opt(int argc, char **argv)
 		case 'N':
 			cfg_print_nsec = true;
 			break;
+		case 'o':
+			ts_opt_id = strtoul(optarg, NULL, 10);
+			cfg_use_cmsg_opt_id = true;
+			break;
 		case 'p':
 			dest_port = strtoul(optarg, NULL, 10);
 			break;
@@ -803,6 +825,8 @@ static void parse_opt(int argc, char **argv)
 		error(1, 0, "cannot ask for pktinfo over pf_packet");
 	if (cfg_busy_poll && cfg_use_epoll)
 		error(1, 0, "pass epoll or busy_poll, not both");
+	if (cfg_proto == SOCK_STREAM && cfg_use_cmsg_opt_id)
+		error(1, 0, "TCP sockets don't support SCM_TS_OPT_ID");
 
 	if (optind != argc - 1)
 		error(1, 0, "missing required hostname argument");
diff --git a/tools/testing/selftests/net/txtimestamp.sh b/tools/testing/selftests/net/txtimestamp.sh
index 25baca4b148e..fe4649bb8786 100755
--- a/tools/testing/selftests/net/txtimestamp.sh
+++ b/tools/testing/selftests/net/txtimestamp.sh
@@ -37,11 +37,13 @@ run_test_v4v6() {
 run_test_tcpudpraw() {
 	local -r args=$@
 
-	run_test_v4v6 ${args}		# tcp
-	run_test_v4v6 ${args} -u	# udp
-	run_test_v4v6 ${args} -r	# raw
-	run_test_v4v6 ${args} -R	# raw (IPPROTO_RAW)
-	run_test_v4v6 ${args} -P	# pf_packet
+	run_test_v4v6 ${args}		  # tcp
+	run_test_v4v6 ${args} -u	  # udp
+	run_test_v4v6 ${args} -u -o 42	  # udp with fixed tskey
+	run_test_v4v6 ${args} -r	  # raw
+	run_test_v4v6 ${args} -r -o 42	  # raw
+	run_test_v4v6 ${args} -R	  # raw (IPPROTO_RAW)
+	run_test_v4v6 ${args} -P	  # pf_packet
 }
 
 run_test_all() {
-- 
2.43.5

Re: [PATCH net-next v5 1/3] net_tstamp: add SCM_TS_OPT_ID to provide OPT_ID in control message

[Jason Xing]

On Wed, Sep 11, 2024 at 5:13 PM Vadim Fedorenko <vadfed@meta.com> wrote:
>
> SOF_TIMESTAMPING_OPT_ID socket option flag gives a way to correlate TX
> timestamps and packets sent via socket. Unfortunately, there is no way
> to reliably predict socket timestamp ID value in case of error returned
> by sendmsg. For UDP sockets it's impossible because of lockless
> nature of UDP transmit, several threads may send packets in parallel. In
> case of RAW sockets MSG_MORE option makes things complicated. More
> details are in the conversation [1].
> This patch adds new control message type to give user-space
> software an opportunity to control the mapping between packets and
> values by providing ID with each sendmsg for UDP sockets.
> The documentation is also added in this patch.
>
> [1] https://lore.kernel.org/netdev/CALCETrU0jB+kg0mhV6A8mrHfTE1D1pr1SD_B9Eaa9aDPfgHdtA@mail.gmail.com/
>
> Reviewed-by: Willem de Bruijn <willemb@google.com>
> Signed-off-by: Vadim Fedorenko <vadfed@meta.com>

Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>

Thanks!

Re: [PATCH net-next v5 2/3] net_tstamp: add SCM_TS_OPT_ID for RAW sockets

[Jason Xing]

On Wed, Sep 11, 2024 at 5:13 PM Vadim Fedorenko <vadfed@meta.com> wrote:
>
> The last type of sockets which supports SOF_TIMESTAMPING_OPT_ID is RAW
> sockets. To add new option this patch converts all callers (direct and
> indirect) of _sock_tx_timestamp to provide sockcm_cookie instead of
> tsflags. And while here fix __sock_tx_timestamp to receive tsflags as
> __u32 instead of __u16.
>
> Reviewed-by: Willem de Bruijn <willemb@google.com>
> Signed-off-by: Vadim Fedorenko <vadfed@meta.com>

Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>

Thanks!

Re: [PATCH net-next v5 0/3] Add option to provide OPT_ID value via cmsg

[Jakub Kicinski]

On Wed, 11 Sep 2024 02:13:30 -0700 Vadim Fedorenko wrote:
> SOF_TIMESTAMPING_OPT_ID socket option flag gives a way to correlate TX
> timestamps and packets sent via socket. Unfortunately, there is no way
> to reliably predict socket timestamp ID value in case of error returned
> by sendmsg. For UDP sockets it's impossible because of lockless
> nature of UDP transmit, several threads may send packets in parallel. In
> case of RAW sockets MSG_MORE option makes things complicated. More
> details are in the conversation [1].
> This patch adds new control message type to give user-space
> software an opportunity to control the mapping between packets and
> values by providing ID with each sendmsg.

Does not apply to net-next any more, sorry :(
-- 
pw-bot: cr