Store an ifp index instead of a pointer in the "struct mbuf_ext".

This is part of the plan to remove the ifp pointer from the packet
header that will allow us to stop garbage collecting mbuf(9)s when
an ifp is detached/destroyed.

ok mikeb@, lteo@, benno@

3 files changed, 17 insertions, 11 deletions

diff --git a/share/man/man9/mbuf.9 b/share/man/man9/mbuf.9
index cf3c308ea8e..18d7392bac9 100644
--- a/share/man/man9/mbuf.9
+++ b/share/man/man9/mbuf.9
@@ -1,4 +1,4 @@
-.\"     $OpenBSD: mbuf.9,v 1.69 2014/03/19 10:09:19 mpi Exp $
+.\"     $OpenBSD: mbuf.9,v 1.70 2014/03/27 10:30:58 mpi Exp $
 .\"
 .\" Copyright (c) 2001 Jean-Jacques Bernard-Gundol <jjbg@openbsd.org>
 .\" All rights reserved.
@@ -25,7 +25,7 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: March 19 2014 $
+.Dd $Mdocdate: March 27 2014 $
 .Dt MBUF 9
 .Os
 .Sh NAME
@@ -140,7 +140,7 @@ struct mbuf_ext {
 	void    *ext_arg;
 	u_int   ext_size;
 	int     ext_type;
-	struct ifnet* ext_ifp;
+	u_short ext_ifidx;
 	int     ext_backend;
 	struct mbuf *ext_nextref;
 	struct mbuf *ext_prevref;
diff --git a/sys/kern/uipc_mbuf.c b/sys/kern/uipc_mbuf.c
index fb481c133f1..3e3a975c8f3 100644
--- a/sys/kern/uipc_mbuf.c
+++ b/sys/kern/uipc_mbuf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_mbuf.c,v 1.178 2014/01/19 03:04:54 claudio Exp $	*/
+/*	$OpenBSD: uipc_mbuf.c,v 1.179 2014/03/27 10:30:58 mpi Exp $	*/
 /*	$NetBSD: uipc_mbuf.c,v 1.15.4.1 1996/06/13 17:11:44 cgd Exp $	*/
 
 /*
@@ -402,15 +402,18 @@ void
 m_cluncount(struct mbuf *m, int all)
 {
 	struct mbuf_ext *me;
+	struct ifnet *ifp;
 
 	do {
 		me = &m->m_ext;
 		if (((m->m_flags & (M_EXT|M_CLUSTER)) != (M_EXT|M_CLUSTER)) ||
-		    (me->ext_ifp == NULL))
+		    (me->ext_ifidx == 0))
 			continue;
 
-		me->ext_ifp->if_data.ifi_mclpool[me->ext_backend].mcl_alive--;
-		me->ext_ifp = NULL;
+		ifp = if_get(me->ext_ifidx);
+		if (ifp != NULL)
+			ifp->if_data.ifi_mclpool[me->ext_backend].mcl_alive--;
+		me->ext_ifidx = 0;
 	} while (all && (m = m->m_next));
 }
 
@@ -460,7 +463,10 @@ m_clget(struct mbuf *m, int how, struct ifnet *ifp, u_int pktlen)
 	m->m_ext.ext_free = NULL;
 	m->m_ext.ext_arg = NULL;
 	m->m_ext.ext_backend = pi;
-	m->m_ext.ext_ifp = ifp;
+	if (ifp != NULL)
+		m->m_ext.ext_ifidx = ifp->if_index;
+	else
+		m->m_ext.ext_ifidx = 0;
 	MCLINITREFERENCE(m);
 	return (m);
 }
@@ -1375,7 +1381,7 @@ m_print(void *v,
 		    m->m_ext.ext_buf, m->m_ext.ext_size);
 		(*pr)("m_ext.ext_type: %x\tm_ext.ext_backend: %i\n",
 		    m->m_ext.ext_type, m->m_ext.ext_backend);
-		(*pr)("m_ext.ext_ifp: %p\n", m->m_ext.ext_ifp);
+		(*pr)("m_ext.ext_ifidx: %u\n", m->m_ext.ext_ifidx);
 		(*pr)("m_ext.ext_free: %p\tm_ext.ext_arg: %p\n",
 		    m->m_ext.ext_free, m->m_ext.ext_arg);
 		(*pr)("m_ext.ext_nextref: %p\tm_ext.ext_prevref: %p\n",
diff --git a/sys/sys/mbuf.h b/sys/sys/mbuf.h
index 471f7bb7a35..dfcd4ecfd65 100644
--- a/sys/sys/mbuf.h
+++ b/sys/sys/mbuf.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mbuf.h,v 1.173 2014/03/19 10:09:20 mpi Exp $	*/
+/*	$OpenBSD: mbuf.h,v 1.174 2014/03/27 10:30:58 mpi Exp $	*/
 /*	$NetBSD: mbuf.h,v 1.19 1996/02/09 18:25:14 christos Exp $	*/
 
 /*
@@ -130,7 +130,7 @@ struct mbuf_ext {
 	void	*ext_arg;		/* argument for ext_free */
 	u_int	ext_size;		/* size of buffer, for ext_free */
 	int	ext_type;
-	struct ifnet* ext_ifp;
+	u_short	ext_ifidx;		/* index of the interface */
 	int	ext_backend;		/* backend pool the storage came from */
 	struct mbuf *ext_nextref;
 	struct mbuf *ext_prevref;