svn commit: r204893 - stable/8/sys/netinet6

[Qing Li]

Author: qingli
Date: Mon Mar  8 21:30:12 2010
New Revision: 204893
URL: http://svn.freebsd.org/changeset/base/204893

Log:
  MFC 204402
  
  Use reference counting instead of locking to secure an address while
  that address is being used to generate temporary IPv6 address. This
  approach is sufficient and avoids recursive locking.

Modified:
  stable/8/sys/netinet6/nd6.c
Directory Properties:
  stable/8/sys/   (props changed)
  stable/8/sys/amd64/include/xen/   (props changed)
  stable/8/sys/cddl/contrib/opensolaris/   (props changed)
  stable/8/sys/contrib/dev/acpica/   (props changed)
  stable/8/sys/contrib/pf/   (props changed)
  stable/8/sys/dev/xen/xenpci/   (props changed)
  stable/8/sys/netinet/   (props changed)

Modified: stable/8/sys/netinet6/nd6.c
==============================================================================
--- stable/8/sys/netinet6/nd6.c	Mon Mar  8 21:29:09 2010	(r204892)
+++ stable/8/sys/netinet6/nd6.c	Mon Mar  8 21:30:12 2010	(r204893)
@@ -759,22 +759,25 @@ regen_tmpaddr(struct in6_ifaddr *ia6)
 		 */
 		if (!IFA6_IS_DEPRECATED(it6))
 		    public_ifa6 = it6;
+
+		if (public_ifa6 != NULL)
+			ifa_ref(&public_ifa6->ia_ifa);
 	}
+	IF_ADDR_UNLOCK(ifp);
 
 	if (public_ifa6 != NULL) {
 		int e;
 
 		if ((e = in6_tmpifadd(public_ifa6, 0, 0)) != 0) {
-			IF_ADDR_UNLOCK(ifp);
+			ifa_free(&public_ifa6->ia_ifa);
 			log(LOG_NOTICE, "regen_tmpaddr: failed to create a new"
 			    " tmp addr,errno=%d\n", e);
 			return (-1);
 		}
-		IF_ADDR_UNLOCK(ifp);
+		ifa_free(&public_ifa6->ia_ifa);
 		return (0);
 	}
 
-	IF_ADDR_UNLOCK(ifp);
 	return (-1);
 }