svn commit: r189873 - head/sys/net

[Robert Watson]

Author: rwatson
Date: Mon Mar 16 10:56:50 2009
New Revision: 189873
URL: http://svn.freebsd.org/changeset/base/189873

Log:
  Define and use two macros for loopback checksum offload:
  
  LO_CSUM_FEATURES - a bitmask of supported transmit offload features, which
    will be stored in if_hwassist if IFCAP_TXCSUM is enabled, and be cleared
    from mbuf packet header csum flags on transmit. (1)
  
  LO_CSUM_SET - a bitmask of supported receive offload features, which will
    be set on the mbuf packet header csum flags on transmit if IFCAP_RXCSUM
    is enabled.
  
  While here, fix SCTP offload for loopback: offer generation on the
  transmit side, don't just skip validation on the receive side.
  
  Obtained from:  DragonflyBSD (1)
  MFC after:      1 week

Modified:
  head/sys/net/if_loop.c

Modified: head/sys/net/if_loop.c
==============================================================================
--- head/sys/net/if_loop.c	Mon Mar 16 10:36:24 2009	(r189872)
+++ head/sys/net/if_loop.c	Mon Mar 16 10:56:50 2009	(r189873)
@@ -94,6 +94,11 @@
 #define LOMTU	16384
 #endif
 
+#define	LO_CSUM_FEATURES	(CSUM_IP | CSUM_TCP | CSUM_UDP | CSUM_SCTP)
+#define	LO_CSUM_SET		(CSUM_DATA_VALID | CSUM_PSEUDO_HDR | \
+				    CSUM_IP_CHECKED | CSUM_IP_VALID | \
+				    CSUM_SCTP_VALID)
+
 int		loioctl(struct ifnet *, u_long, caddr_t);
 static void	lortrequest(int, struct rtentry *, struct rt_addrinfo *);
 int		looutput(struct ifnet *ifp, struct mbuf *m,
@@ -139,7 +144,7 @@ lo_clone_create(struct if_clone *ifc, in
 	ifp->if_output = looutput;
 	ifp->if_snd.ifq_maxlen = ifqmaxlen;
 	ifp->if_capabilities = ifp->if_capenable = IFCAP_HWCSUM;
-	ifp->if_hwassist = CSUM_IP | CSUM_TCP | CSUM_UDP;
+	ifp->if_hwassist = LO_CSUM_FEATURES;
 	if_attach(ifp);
 	bpfattach(ifp, DLT_NULL, sizeof(u_int32_t));
 	if (V_loif == NULL)
@@ -216,11 +221,9 @@ looutput(struct ifnet *ifp, struct mbuf 
 	case AF_INET:
 		if (ifp->if_capenable & IFCAP_RXCSUM) {
 			m->m_pkthdr.csum_data = 0xffff;
-			m->m_pkthdr.csum_flags = CSUM_DATA_VALID |
-			    CSUM_PSEUDO_HDR | CSUM_IP_CHECKED |
-			    CSUM_IP_VALID | CSUM_SCTP_VALID;
+			m->m_pkthdr.csum_flags = LO_CSUM_SET;
 		}
-		m->m_pkthdr.csum_flags &= ~(CSUM_IP | CSUM_TCP | CSUM_UDP);
+		m->m_pkthdr.csum_flags &= ~LO_CSUM_FEATURES;
 	case AF_INET6:
 	case AF_IPX:
 	case AF_APPLETALK:
@@ -407,7 +410,7 @@ loioctl(struct ifnet *ifp, u_long cmd, c
 		if ((mask & IFCAP_TXCSUM) != 0)
 			ifp->if_capenable ^= IFCAP_TXCSUM;
 		if (ifp->if_capenable & IFCAP_TXCSUM)
-			ifp->if_hwassist = CSUM_IP | CSUM_TCP | CSUM_UDP;
+			ifp->if_hwassist = LO_CSUM_FEATURES;
 		else
 			ifp->if_hwassist = 0;
 		break;