MCLGETI() will now allocate a mbuf header if it is not provided, thus

reducing the amount of splnet/splx dancing required.. especially in the
worst case (of m_cldrop)
ok dlg kettenis damien

18 files changed, 76 insertions, 170 deletions

diff --git a/share/man/man9/mbuf.9 b/share/man/man9/mbuf.9
index 8b24883cd1f..ca2c7b6e682 100644
--- a/share/man/man9/mbuf.9
+++ b/share/man/man9/mbuf.9
@@ -1,4 +1,4 @@
-.\"     $OpenBSD: mbuf.9,v 1.43 2009/03/02 23:37:08 blambert Exp $
+.\"     $OpenBSD: mbuf.9,v 1.44 2009/08/09 11:40:58 deraadt 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 2 2009 $
+.Dd $Mdocdate: August 9 2009 $
 .Dt MBUF 9
 .Os
 .Sh NAME
@@ -84,6 +84,7 @@
 .Fn m_apply "struct mbuf *m" "int off" "int len" \
 "int (*func)(caddr_t, caddr_t, unsigned int)" "caddr_t fstate"
 .Fn MCLGET "struct mbuf *m" "int how"
+.Ft struct mbuf *
 .Fn MCLGETI "struct mbuf *m" "int how" "struct ifnet *ifp" "int len"
 .Fn MEXTADD "struct mbuf *m" "caddr_t buf" "u_int size" "int type" \
 "void (*free)(caddr_t, u_int, void *)" "void *arg"
diff --git a/sys/arch/socppc/dev/if_tsec.c b/sys/arch/socppc/dev/if_tsec.c
index bca792b7a21..ca377948d2d 100644
--- a/sys/arch/socppc/dev/if_tsec.c
+++ b/sys/arch/socppc/dev/if_tsec.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_tsec.c,v 1.22 2009/02/22 20:03:19 kettenis Exp $	*/
+/*	$OpenBSD: if_tsec.c,v 1.23 2009/08/09 11:40:58 deraadt Exp $	*/
 
 /*
  * Copyright (c) 2008 Mark Kettenis
@@ -1196,15 +1196,9 @@ tsec_alloc_mbuf(struct tsec_softc *sc, bus_dmamap_t map)
 {
 	struct mbuf *m = NULL;
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->sc_ac.ac_if, MCLBYTES);
+	if (!m)
 		return (NULL);
-
-	MCLGETI(m, M_DONTWAIT, &sc->sc_ac.ac_if, MCLBYTES);
-	if ((m->m_flags & M_EXT) == 0) {
-		m_freem(m);
-		return (NULL);
-	}
 	m->m_len = m->m_pkthdr.len = MCLBYTES;
 
 	if (bus_dmamap_load_mbuf(sc->sc_dmat, map, m, BUS_DMA_NOWAIT) != 0) {
diff --git a/sys/arch/sparc64/dev/vnet.c b/sys/arch/sparc64/dev/vnet.c
index 0364bddfa7f..c7cac05fbf9 100644
--- a/sys/arch/sparc64/dev/vnet.c
+++ b/sys/arch/sparc64/dev/vnet.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vnet.c,v 1.16 2009/05/12 21:33:38 kettenis Exp $	*/
+/*	$OpenBSD: vnet.c,v 1.17 2009/08/09 11:40:58 deraadt Exp $	*/
 /*
  * Copyright (c) 2009 Mark Kettenis
  *
@@ -681,14 +681,10 @@ vnet_rx_vio_dring_data(struct vnet_softc *sc, struct vio_msg_tag *tag)
 			if (desc.hdr.dstate != VIO_DESC_READY)
 				break;
 
-			MGETHDR(m, M_DONTWAIT, MT_DATA);
-			if(m == NULL)
+			m = MCLGETI(NULL, M_DONTWAIT, &sc->sc_ac.ac_if,
+			    MCLBYTES);
+			if (!m)
 				break;
-			MCLGETI(m, M_DONTWAIT, &sc->sc_ac.ac_if, MCLBYTES);
-			if ((m->m_flags & M_EXT) == 0) {
-				m_freem(m);
-				break;
-			}
 			ifp->if_ipackets++;
 			m->m_pkthdr.rcvif = ifp;
 			m->m_len = m->m_pkthdr.len = desc.nbytes;
diff --git a/sys/dev/ic/gem.c b/sys/dev/ic/gem.c
index 851010ab767..9a02283a960 100644
--- a/sys/dev/ic/gem.c
+++ b/sys/dev/ic/gem.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: gem.c,v 1.93 2009/08/03 11:09:10 sthen Exp $	*/
+/*	$OpenBSD: gem.c,v 1.94 2009/08/09 11:40:58 deraadt Exp $	*/
 /*	$NetBSD: gem.c,v 1.1 2001/09/16 00:11:43 eeh Exp $ */
 
 /*
@@ -1006,15 +1006,9 @@ gem_add_rxbuf(struct gem_softc *sc, int idx)
 	struct mbuf *m;
 	int error;
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->sc_arpcom.ac_if, MCLBYTES);
+	if (!m)
 		return (ENOBUFS);
-
-	MCLGETI(m, M_DONTWAIT, &sc->sc_arpcom.ac_if, MCLBYTES);
-	if ((m->m_flags & M_EXT) == 0) {
-		m_freem(m);
-		return (ENOBUFS);
-	}
 	m->m_len = m->m_pkthdr.len = MCLBYTES;
 
 #ifdef GEM_DEBUG
diff --git a/sys/dev/ic/hme.c b/sys/dev/ic/hme.c
index e5fa4e266ad..3c5a9413a59 100644
--- a/sys/dev/ic/hme.c
+++ b/sys/dev/ic/hme.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: hme.c,v 1.58 2009/06/22 14:31:04 sthen Exp $	*/
+/*	$OpenBSD: hme.c,v 1.59 2009/08/09 11:40:58 deraadt Exp $	*/
 /*	$NetBSD: hme.c,v 1.21 2001/07/07 15:59:37 thorpej Exp $	*/
 
 /*-
@@ -1415,17 +1415,11 @@ hme_newbuf(sc, d)
 	 * until we're sure everything is a success.
 	 */
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->sc_arpcom.ac_if, MCLBYTES);
+	if (!m)
 		return (ENOBUFS);
 	m->m_pkthdr.rcvif = &sc->sc_arpcom.ac_if;
 
-	MCLGETI(m, M_DONTWAIT, &sc->sc_arpcom.ac_if, MCLBYTES);
-	if ((m->m_flags & M_EXT) == 0) {
-		m_freem(m);
-		return (ENOBUFS);
-	}
-
 	if (bus_dmamap_load(sc->sc_dmatag, sc->sc_rxmap_spare,
 	    mtod(m, caddr_t), MCLBYTES - HME_RX_OFFSET, NULL,
 	    BUS_DMA_NOWAIT) != 0) {
diff --git a/sys/dev/ic/re.c b/sys/dev/ic/re.c
index e3caa4bae14..e6cbd4bf963 100644
--- a/sys/dev/ic/re.c
+++ b/sys/dev/ic/re.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: re.c,v 1.113 2009/07/23 20:15:32 kettenis Exp $	*/
+/*	$OpenBSD: re.c,v 1.114 2009/08/09 11:40:58 deraadt Exp $	*/
 /*	$FreeBSD: if_re.c,v 1.31 2004/09/04 07:54:05 ru Exp $	*/
 /*
  * Copyright (c) 1997, 1998-2003
@@ -1213,16 +1213,10 @@ re_newbuf(struct rl_softc *sc)
 	u_int32_t	cmdstat;
 	int		error, idx;
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->sc_arpcom.ac_if, MCLBYTES);
+	if (!m)
 		return (ENOBUFS);
 
-	MCLGETI(m, M_DONTWAIT, &sc->sc_arpcom.ac_if, MCLBYTES);
-	if ((m->m_flags & M_EXT) == 0) {
-		m_freem(m);
-		return (ENOBUFS);
-	}
-
 	/*
 	 * Initialize mbuf length fields and fixup
 	 * alignment so that the frame payload is
diff --git a/sys/dev/pci/if_bge.c b/sys/dev/pci/if_bge.c
index f03f1415002..8f8986974f1 100644
--- a/sys/dev/pci/if_bge.c
+++ b/sys/dev/pci/if_bge.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_bge.c,v 1.279 2009/08/08 15:58:14 naddy Exp $	*/
+/*	$OpenBSD: if_bge.c,v 1.280 2009/08/09 11:40:56 deraadt Exp $	*/
 
 /*
  * Copyright (c) 2001 Wind River Systems
@@ -719,15 +719,9 @@ bge_newbuf(struct bge_softc *sc, int i)
 	struct mbuf		*m;
 	int			error;
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->arpcom.ac_if, MCLBYTES);
+	if (!m)
 		return (ENOBUFS);
-
-	MCLGETI(m, M_DONTWAIT, &sc->arpcom.ac_if, MCLBYTES);
-	if (!(m->m_flags & M_EXT)) {
-		m_freem(m);
-		return (ENOBUFS);
-	}
 	m->m_len = m->m_pkthdr.len = MCLBYTES;
 	if (!(sc->bge_flags & BGE_RX_ALIGNBUG))
 	    m_adj(m, ETHER_ALIGN);
@@ -776,15 +770,9 @@ bge_newbuf_jumbo(struct bge_softc *sc, int i)
 	struct mbuf		*m;
 	int			error;
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->arpcom.ac_if, BGE_JLEN);
+	if (!m)
 		return (ENOBUFS);
-
-	MCLGETI(m, M_DONTWAIT, &sc->arpcom.ac_if, BGE_JLEN);
-	if (!(m->m_flags & M_EXT)) {
-		m_freem(m);
-		return (ENOBUFS);
-	}
 	m->m_len = m->m_pkthdr.len = BGE_JUMBO_FRAMELEN;
 	if (!(sc->bge_flags & BGE_RX_ALIGNBUG))
 	    m_adj(m, ETHER_ALIGN);
diff --git a/sys/dev/pci/if_bnx.c b/sys/dev/pci/if_bnx.c
index e0f0de5c17a..3bf0151bdf1 100644
--- a/sys/dev/pci/if_bnx.c
+++ b/sys/dev/pci/if_bnx.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_bnx.c,v 1.82 2009/08/06 19:53:13 sthen Exp $	*/
+/*	$OpenBSD: if_bnx.c,v 1.83 2009/08/09 11:40:56 deraadt Exp $	*/
 
 /*-
  * Copyright (c) 2006 Broadcom Corporation
@@ -3591,16 +3591,9 @@ bnx_get_buf(struct bnx_softc *sc, u_int16_t *prod,
 	    *prod_bseq);
 
 	/* This is a new mbuf allocation. */
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->arpcom.ac_if, MCLBYTES);
+	if (!m)
 		return (ENOBUFS);
-
-	/* Attach a cluster to the mbuf. */
-	MCLGETI(m, M_DONTWAIT, &sc->arpcom.ac_if, MCLBYTES);
-	if (!(m->m_flags & M_EXT)) {
-		m_freem(m);
-		return (ENOBUFS);
-	}
 	m->m_len = m->m_pkthdr.len = MCLBYTES;
 	/* the chip aligns the ip header for us, no need to m_adj */
 
diff --git a/sys/dev/pci/if_em.c b/sys/dev/pci/if_em.c
index 7dbec34a729..9a7155f2ab6 100644
--- a/sys/dev/pci/if_em.c
+++ b/sys/dev/pci/if_em.c
@@ -31,7 +31,7 @@ POSSIBILITY OF SUCH DAMAGE.
 
 ***************************************************************************/
 
-/* $OpenBSD: if_em.c,v 1.215 2009/07/27 16:37:52 claudio Exp $ */
+/* $OpenBSD: if_em.c,v 1.216 2009/08/09 11:40:56 deraadt Exp $ */
 /* $FreeBSD: if_em.c,v 1.46 2004/09/29 18:28:28 mlaier Exp $ */
 
 #include <dev/pci/if_em.h>
@@ -2307,14 +2307,8 @@ em_get_buf(struct em_softc *sc, int i)
 		return (ENOBUFS);
 	}
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL) {
-		sc->mbuf_alloc_failed++;
-		return (ENOBUFS);
-	}
-	MCLGETI(m, M_DONTWAIT, &sc->interface_data.ac_if, MCLBYTES);
-	if ((m->m_flags & M_EXT) == 0) {
-		m_freem(m);
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->interface_data.ac_if, MCLBYTES);
+	if (!m) {
 		sc->mbuf_cluster_failed++;
 		return (ENOBUFS);
 	}
diff --git a/sys/dev/pci/if_iwn.c b/sys/dev/pci/if_iwn.c
index bc6c2d431ee..76883231278 100644
--- a/sys/dev/pci/if_iwn.c
+++ b/sys/dev/pci/if_iwn.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_iwn.c,v 1.60 2009/07/10 07:44:04 blambert Exp $	*/
+/*	$OpenBSD: if_iwn.c,v 1.61 2009/08/09 11:40:56 deraadt Exp $	*/
 
 /*-
  * Copyright (c) 2007-2009 Damien Bergamini <damien.bergamini@free.fr>
@@ -1010,15 +1010,8 @@ iwn_alloc_rx_ring(struct iwn_softc *sc, struct iwn_rx_ring *ring)
 			goto fail;
 		}
 
-		MGETHDR(data->m, M_DONTWAIT, MT_DATA);
-		if (data->m == NULL) {
-			printf("%s: could not allocate RX mbuf\n",
-			    sc->sc_dev.dv_xname);
-			error = ENOMEM;
-			goto fail;
-		}
-		MCLGETI(data->m, M_DONTWAIT, NULL, IWN_RBUF_SIZE);
-		if (!(data->m->m_flags & M_EXT)) {
+		data->m = MCLGETI(NULL, M_DONTWAIT, NULL, IWN_RBUF_SIZE);
+		if (!data->m) {
 			printf("%s: could not allocate RX mbuf cluster\n",
 			    sc->sc_dev.dv_xname);
 			error = ENOBUFS;
@@ -1704,15 +1697,8 @@ iwn_rx_done(struct iwn_softc *sc, struct iwn_rx_desc *desc,
 		return;
 	}
 
-	MGETHDR(m1, M_DONTWAIT, MT_DATA);
-	if (m1 == NULL) {
-		ic->ic_stats.is_rx_nombuf++;
-		ifp->if_ierrors++;
-		return;
-	}
-	MCLGETI(m1, M_DONTWAIT, NULL, IWN_RBUF_SIZE);
-	if (!(m1->m_flags & M_EXT)) {
-		m_freem(m1);
+	m1 = MCLGETI(NULL, M_DONTWAIT, NULL, IWN_RBUF_SIZE);
+	if (!m1) {
 		ic->ic_stats.is_rx_nombuf++;
 		ifp->if_ierrors++;
 		return;
diff --git a/sys/dev/pci/if_ix.c b/sys/dev/pci/if_ix.c
index e4a03ef8e93..067efcc2b69 100644
--- a/sys/dev/pci/if_ix.c
+++ b/sys/dev/pci/if_ix.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_ix.c,v 1.24 2009/07/10 12:00:52 dlg Exp $	*/
+/*	$OpenBSD: if_ix.c,v 1.25 2009/08/09 11:40:56 deraadt Exp $	*/
 
 /******************************************************************************
 
@@ -2217,14 +2217,8 @@ ixgbe_get_buf(struct rx_ring *rxr, int i)
 		return (ENOBUFS);
 	}
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL) {
-		sc->mbuf_alloc_failed++;
-		return (ENOBUFS);
-	}
-	MCLGETI(m, M_DONTWAIT, &sc->arpcom.ac_if, size);
-	if ((m->m_flags & M_EXT) == 0) {
-		m_freem(m);
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->arpcom.ac_if, size);
+	if (!m) {
 		sc->mbuf_cluster_failed++;
 		return (ENOBUFS);
 	}
diff --git a/sys/dev/pci/if_msk.c b/sys/dev/pci/if_msk.c
index 9cc0ef3dad6..387837302e0 100644
--- a/sys/dev/pci/if_msk.c
+++ b/sys/dev/pci/if_msk.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_msk.c,v 1.75 2009/03/29 14:36:34 jsg Exp $	*/
+/*	$OpenBSD: if_msk.c,v 1.76 2009/08/09 11:40:56 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1997, 1998, 1999, 2000
@@ -503,15 +503,9 @@ msk_newbuf(struct sk_if_softc *sc_if)
 	int			error;
 	int			opcode, i;
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc_if->arpcom.ac_if, sc_if->sk_pktlen);
+	if (!m)
 		return (ENOBUFS);
-
-	MCLGETI(m, M_DONTWAIT, &sc_if->arpcom.ac_if, sc_if->sk_pktlen);
-	if ((m->m_flags & M_EXT) == 0) {
-		m_freem(m);
-		return (ENOBUFS);
-	}
 	m->m_len = m->m_pkthdr.len = sc_if->sk_pktlen;
 	m_adj(m, ETHER_ALIGN);
 
diff --git a/sys/dev/pci/if_sis.c b/sys/dev/pci/if_sis.c
index bc8a6d9cfa6..3fb8be5af3b 100644
--- a/sys/dev/pci/if_sis.c
+++ b/sys/dev/pci/if_sis.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_sis.c,v 1.94 2009/07/22 21:32:50 miod Exp $ */
+/*	$OpenBSD: if_sis.c,v 1.95 2009/08/09 11:40:56 deraadt Exp $ */
 /*
  * Copyright (c) 1997, 1998, 1999
  *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
@@ -1232,16 +1232,10 @@ sis_newbuf(struct sis_softc *sc, struct sis_desc *c)
 	if (c == NULL)
 		return (EINVAL);
 
-	MGETHDR(m_new, M_DONTWAIT, MT_DATA);
-	if (m_new == NULL)
+	m_new = MCLGETI(NULL, M_DONTWAIT, &sc->arpcom.ac_if, MCLBYTES);
+	if (!m_new)
 		return (ENOBUFS);
 
-	MCLGETI(m_new, M_DONTWAIT, &sc->arpcom.ac_if, MCLBYTES);
-	if (!(m_new->m_flags & M_EXT)) {
-		m_free(m_new);
-		return (ENOBUFS);
-	}
-
 	m_new->m_len = m_new->m_pkthdr.len = MCLBYTES;
 
 	if (bus_dmamap_load_mbuf(sc->sc_dmat, c->map, m_new,
diff --git a/sys/dev/pci/if_vic.c b/sys/dev/pci/if_vic.c
index cbe5345796f..3a5e9c1f0de 100644
--- a/sys/dev/pci/if_vic.c
+++ b/sys/dev/pci/if_vic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_vic.c,v 1.71 2009/06/02 12:32:06 deraadt Exp $	*/
+/*	$OpenBSD: if_vic.c,v 1.72 2009/08/09 11:40:56 deraadt Exp $	*/
 
 /*
  * Copyright (c) 2006 Reyk Floeter <reyk@openbsd.org>
@@ -1340,15 +1340,9 @@ vic_alloc_mbuf(struct vic_softc *sc, bus_dmamap_t map, u_int pktlen)
 {
 	struct mbuf *m = NULL;
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->sc_ac.ac_if, pktlen);
+	if (!m)
 		return (NULL);
-
-	MCLGETI(m, M_DONTWAIT, &sc->sc_ac.ac_if, pktlen);
-	if ((m->m_flags & M_EXT) == 0) {
-		m_freem(m);
-		return (NULL);
-	}
 	m->m_data += ETHER_ALIGN;
 	m->m_len = m->m_pkthdr.len = pktlen - ETHER_ALIGN;
 
diff --git a/sys/dev/pci/if_vr.c b/sys/dev/pci/if_vr.c
index 1dbe51a569e..4c961ebe1c2 100644
--- a/sys/dev/pci/if_vr.c
+++ b/sys/dev/pci/if_vr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_vr.c,v 1.97 2009/06/18 18:53:02 claudio Exp $	*/
+/*	$OpenBSD: if_vr.c,v 1.98 2009/08/09 11:40:56 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1997, 1998
@@ -1568,16 +1568,10 @@ vr_alloc_mbuf(struct vr_softc *sc, struct vr_chain_onefrag *r)
 	if (r == NULL)
 		return (EINVAL);
 
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
-	if (m == NULL)
+	m = MCLGETI(NULL, M_DONTWAIT, &sc->arpcom.ac_if, MCLBYTES);
+	if (!m)
 		return (ENOBUFS);
 
-	MCLGETI(m, M_DONTWAIT, &sc->arpcom.ac_if, MCLBYTES);
-	if (!(m->m_flags & M_EXT)) {
-		m_free(m);
-		return (ENOBUFS);
-	}
-
 	m->m_len = m->m_pkthdr.len = MCLBYTES;
 	m_adj(m, sizeof(u_int64_t));
 
diff --git a/sys/dev/pci/if_wpi.c b/sys/dev/pci/if_wpi.c
index d52562647fe..ccd1cd72728 100644
--- a/sys/dev/pci/if_wpi.c
+++ b/sys/dev/pci/if_wpi.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: if_wpi.c,v 1.89 2009/07/11 13:28:36 blambert Exp $	*/
+/*	$OpenBSD: if_wpi.c,v 1.90 2009/08/09 11:40:56 deraadt Exp $	*/
 
 /*-
  * Copyright (c) 2006-2008
@@ -641,15 +641,8 @@ wpi_alloc_rx_ring(struct wpi_softc *sc, struct wpi_rx_ring *ring)
 			goto fail;
 		}
 
-		MGETHDR(data->m, M_DONTWAIT, MT_DATA);
-		if (data->m == NULL) {
-			printf("%s: could not allocate RX mbuf\n",
-			    sc->sc_dev.dv_xname);
-			error = ENOBUFS;
-			goto fail;
-		}
-		MCLGETI(data->m, M_DONTWAIT, NULL, WPI_RBUF_SIZE);
-		if (!(data->m->m_flags & M_EXT)) {
+		data->m = MCLGETI(NULL, M_DONTWAIT, NULL, WPI_RBUF_SIZE);
+		if (!data->m) {
 			printf("%s: could not allocate RX mbuf cluster\n",
 			    sc->sc_dev.dv_xname);
 			error = ENOBUFS;
@@ -1192,15 +1185,8 @@ wpi_rx_done(struct wpi_softc *sc, struct wpi_rx_desc *desc,
 		return;
 	}
 
-	MGETHDR(m1, M_DONTWAIT, MT_DATA);
-	if (m1 == NULL) {
-		ic->ic_stats.is_rx_nombuf++;
-		ifp->if_ierrors++;
-		return;
-	}
-	MCLGETI(m1, M_DONTWAIT, NULL, WPI_RBUF_SIZE);
-	if (!(m1->m_flags & M_EXT)) {
-		m_freem(m1);
+	m1 = MCLGETI(NULL, M_DONTWAIT, NULL, WPI_RBUF_SIZE);
+	if (!m1) {
 		ic->ic_stats.is_rx_nombuf++;
 		ifp->if_ierrors++;
 		return;
diff --git a/sys/kern/uipc_mbuf.c b/sys/kern/uipc_mbuf.c
index 02d221f0bc5..4d005f58054 100644
--- a/sys/kern/uipc_mbuf.c
+++ b/sys/kern/uipc_mbuf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uipc_mbuf.c,v 1.122 2009/06/22 10:51:06 thib Exp $	*/
+/*	$OpenBSD: uipc_mbuf.c,v 1.123 2009/08/09 11:40:58 deraadt Exp $	*/
 /*	$NetBSD: uipc_mbuf.c,v 1.15.4.1 1996/06/13 17:11:44 cgd Exp $	*/
 
 /*
@@ -386,9 +386,10 @@ m_cluncount(struct mbuf *m, int all)
 	} while (all && (m = m->m_next));
 }
 
-void
+struct mbuf *
 m_clget(struct mbuf *m, int how, struct ifnet *ifp, u_int pktlen)
 {
+	struct mbuf *m0 = NULL;
 	int pi;
 	int s;
 
@@ -399,11 +400,25 @@ m_clget(struct mbuf *m, int how, struct ifnet *ifp, u_int pktlen)
 #endif
 
 	if (ifp != NULL && m_cldrop(ifp, pi))
-		return;
+		return (NULL);
 
 	s = splnet();
+	if (m == NULL) {
+		MGETHDR(m0, M_DONTWAIT, MT_DATA);
+		if (m0 == NULL) {
+			splx(s);
+			return (NULL);
+		}
+		m = m0;
+	}			
 	m->m_ext.ext_buf = pool_get(&mclpools[pi],
 	    how == M_WAIT ? PR_WAITOK : 0);
+	if (!m->m_ext.ext_buf) {
+		if (m0)
+			m_freem(m0);
+		splx(s);
+		return (NULL);
+	}
 	splx(s);
 	if (m->m_ext.ext_buf != NULL) {
 		m->m_data = m->m_ext.ext_buf;
@@ -419,6 +434,7 @@ m_clget(struct mbuf *m, int how, struct ifnet *ifp, u_int pktlen)
 
 		MCLINITREFERENCE(m);
 	}
+	return (m);
 }
 
 struct mbuf *
diff --git a/sys/sys/mbuf.h b/sys/sys/mbuf.h
index 68871411ce6..7ac36d34010 100644
--- a/sys/sys/mbuf.h
+++ b/sys/sys/mbuf.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mbuf.h,v 1.123 2009/06/05 00:05:22 claudio Exp $	*/
+/*	$OpenBSD: mbuf.h,v 1.124 2009/08/09 11:40:58 deraadt Exp $	*/
 /*	$NetBSD: mbuf.h,v 1.19 1996/02/09 18:25:14 christos Exp $	*/
 
 /*
@@ -421,7 +421,7 @@ struct  mbuf *m_inject(struct mbuf *, int, int, int);
 struct  mbuf *m_getptr(struct mbuf *, int, int *);
 int	m_leadingspace(struct mbuf *);
 int	m_trailingspace(struct mbuf *);
-void	m_clget(struct mbuf *, int, struct ifnet *, u_int);
+struct mbuf *m_clget(struct mbuf *, int, struct ifnet *, u_int);
 void	m_clsetwms(struct ifnet *, u_int, u_int, u_int);
 int	m_cldrop(struct ifnet *, int);
 void	m_clcount(struct ifnet *, int);