Merge branch 'net-extend-socket-timestamping-API'

Miroslav Lichvar says:

====================
Extend socket timestamping API

Changes v5->v6:
- fixed skb_is_swtx_tstamp() when OPT_TX_SWHW is disabled and improved
  its description
- improved OPT_PKTINFO documentation
- improved scm_timestamping documentation

Changes v4->v5:
- fixed initialization of reserved fields in struct scm_ts_pktinfo

Changes v3->v4:
- added reserved fields to struct scm_ts_pktinfo
- replaced patch fixing false SW timestamps with a documentation fix
- updated OPT_TX_SWHW patch to handle false SW timestamps

Changes v2->v3:
- modified struct scm_ts_pktinfo to use fixed-width integer types
- added WARN_ON_ONCE for missing RCU lock in dev_get_by_napi_id()
- modified dev_get_by_napi_id() to not return dev in unexpected branch
- modified recv to return SCM_TIMESTAMPING_PKTINFO even if the interface
  index is unknown

Changes v1->v2:
- added separate patch for new NAPI functions
- split code from __sock_recv_timestamp() for better readability
- fixed RCU locking
- fixed compiler warning (missing case in switch in first patch)
- inline sw_tx_timestamp() in its only user

Changes RFC->v1:
- reworked SOF_TIMESTAMPING_OPT_PKTINFO patch to not add new fields to
  skb shared info (net device is now looked up by napi_id), not require
  any changes in drivers, and restrict the cmsg to incoming packets
- renamed SOF_TIMESTAMPING_OPT_MULTIMSG to SOF_TIMESTAMPING_OPT_TX_SWHW
  and fixed its description
- moved struct scm_ts_pktinfo from errqueue.h to net_tstamp.h as it
  can't be received from the error queue anymore
- improved commit descriptions and removed incorrect comment

This patchset adds new options to the timestamping API that will be
useful for NTP implementations and possibly other applications.

The first patch specifies a timestamp filter for NTP packets. The second
patch updates drivers that can timestamp all packets, or need to list
the filter as unsupported. There is no attempt to add the support to the
phyter driver.

The third patch adds two helper functions working with NAPI ID, which is
needed by the next patch. The fourth patch adds a new option to get a
new control message with the L2 length and interface index for incoming
packets with hardware timestamps.

The fifth patch fixes documentation on number of non-zero fields in
scm_timestamping and warns about false software timestamps when
SO_TIMESTAMP(NS) is combined with SCM_TIMESTAMPING.

The sixth patch adds a new option to request both software and hardware
timestamps for outgoing packets. The seventh patch updates drivers that
assumed software timestamping cannot be used together with hardware
timestamping.

The patches have been tested on x86_64 machines with igb and e1000e
drivers.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 28 insertions, 9 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index f8f7cd52a0a0..c50c9218e31e 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2456,6 +2456,7 @@ static inline int dev_recursion_level(void)
 struct net_device *dev_get_by_index(struct net *net, int ifindex);
 struct net_device *__dev_get_by_index(struct net *net, int ifindex);
 struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex);
+struct net_device *dev_get_by_napi_id(unsigned int napi_id);
 int netdev_get_name(struct net *net, char *name, int ifindex);
 int dev_restart(struct net_device *dev);
 int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb);
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 1713e4b7ea9f..45a59c1e0cc7 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -858,6 +858,15 @@ static inline bool skb_pkt_type_ok(u32 ptype)
 	return ptype <= PACKET_OTHERHOST;
 }
 
+static inline unsigned int skb_napi_id(const struct sk_buff *skb)
+{
+#ifdef CONFIG_NET_RX_BUSY_POLL
+	return skb->napi_id;
+#else
+	return 0;
+#endif
+}
+
 void kfree_skb(struct sk_buff *skb);
 void kfree_skb_list(struct sk_buff *segs);
 void skb_tx_error(struct sk_buff *skb);
@@ -3250,13 +3259,6 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb,
 void skb_tstamp_tx(struct sk_buff *orig_skb,
 		   struct skb_shared_hwtstamps *hwtstamps);
 
-static inline void sw_tx_timestamp(struct sk_buff *skb)
-{
-	if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP &&
-	    !(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
-		skb_tstamp_tx(skb, NULL);
-}
-
 /**
  * skb_tx_timestamp() - Driver hook for transmit timestamping
  *
@@ -3272,7 +3274,8 @@ static inline void sw_tx_timestamp(struct sk_buff *skb)
 static inline void skb_tx_timestamp(struct sk_buff *skb)
 {
 	skb_clone_tx_timestamp(skb);
-	sw_tx_timestamp(skb);
+	if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP)
+		skb_tstamp_tx(skb, NULL);
 }
 
 /**
diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
index 2b488565599d..a5f6e819fafd 100644
--- a/include/uapi/asm-generic/socket.h
+++ b/include/uapi/asm-generic/socket.h
@@ -100,4 +100,6 @@
 
 #define SO_COOKIE		57
 
+#define SCM_TIMESTAMPING_PKTINFO	58
+
 #endif /* __ASM_GENERIC_SOCKET_H */
diff --git a/include/uapi/linux/net_tstamp.h b/include/uapi/linux/net_tstamp.h
index 464dcca5ed68..3d421d912193 100644
--- a/include/uapi/linux/net_tstamp.h
+++ b/include/uapi/linux/net_tstamp.h
@@ -9,6 +9,7 @@
 #ifndef _NET_TIMESTAMPING_H
 #define _NET_TIMESTAMPING_H
 
+#include <linux/types.h>
 #include <linux/socket.h>   /* for SO_TIMESTAMPING */
 
 /* SO_TIMESTAMPING gets an integer bit field comprised of these values */
@@ -26,8 +27,10 @@ enum {
 	SOF_TIMESTAMPING_OPT_CMSG = (1<<10),
 	SOF_TIMESTAMPING_OPT_TSONLY = (1<<11),
 	SOF_TIMESTAMPING_OPT_STATS = (1<<12),
+	SOF_TIMESTAMPING_OPT_PKTINFO = (1<<13),
+	SOF_TIMESTAMPING_OPT_TX_SWHW = (1<<14),
 
-	SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_STATS,
+	SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_TX_SWHW,
 	SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) |
 				 SOF_TIMESTAMPING_LAST
 };
@@ -125,6 +128,16 @@ enum hwtstamp_rx_filters {
 	HWTSTAMP_FILTER_PTP_V2_SYNC,
 	/* PTP v2/802.AS1, any layer, Delay_req packet */
 	HWTSTAMP_FILTER_PTP_V2_DELAY_REQ,
+
+	/* NTP, UDP, all versions and packet modes */
+	HWTSTAMP_FILTER_NTP_ALL,
+};
+
+/* SCM_TIMESTAMPING_PKTINFO control message */
+struct scm_ts_pktinfo {
+	__u32 if_index;
+	__u32 pkt_length;
+	__u32 reserved[2];
 };
 
 #endif /* _NET_TIMESTAMPING_H */