From: Jeffrey Hsu <hsu@dragonflybsd.org>
Date: Sun, 29 May 2005 10:08:36 +0000 (+0000)
Subject: Deprecate MCLGET() in favor of m_getcl() or m_getl() in order to
X-Git-Tag: v2.0.1~7249
X-Git-Url: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff_plain/50503f0f827304d16faaebc14b00a77222dd7271

Deprecate MCLGET() in favor of m_getcl() or m_getl() in order to
take advantage of cluster caching.
---

diff --git a/sys/dev/netif/de/if_de.c b/sys/dev/netif/de/if_de.c
index 0ec3529ff5..609afd4125 100644
--- a/sys/dev/netif/de/if_de.c
+++ b/sys/dev/netif/de/if_de.c
@@ -1,7 +1,7 @@
 /*	$NetBSD: if_de.c,v 1.86 1999/06/01 19:17:59 thorpej Exp $	*/
 
 /* $FreeBSD: src/sys/pci/if_de.c,v 1.123.2.4 2000/08/04 23:25:09 peter Exp $ */
-/* $DragonFly: src/sys/dev/netif/de/if_de.c,v 1.36 2005/05/24 20:59:01 dillon Exp $ */
+/* $DragonFly: src/sys/dev/netif/de/if_de.c,v 1.37 2005/05/29 10:08:35 hsu Exp $ */
 
 /*-
  * Copyright (c) 1994-1997 Matt Thomas (matt@3am-software.com)
@@ -3149,20 +3149,16 @@ tulip_rx_intr(tulip_softc_t *sc)
 	 */
 	if (accept || ms == NULL) {
 	    struct mbuf *m0;
-	    MGETHDR(m0, MB_DONTWAIT, MT_DATA);
-	    if (m0 != NULL) {
-#if defined(TULIP_COPY_RXDATA)
-		if (!accept || total_len >= (MHLEN - 2)) {
-#endif
-		    MCLGET(m0, MB_DONTWAIT);
-		    if ((m0->m_flags & M_EXT) == 0) {
-			m_freem(m0);
-			m0 = NULL;
-		    }
+
 #if defined(TULIP_COPY_RXDATA)
-		}
+	    if (!accept || total_len >= (MHLEN - 2))
+		m0 = m_getcl(MB_DONTWAIT, MT_DATA, M_PKTHDR);
+	    else
+		m0 = m_gethdr(MB_DONTWAIT, MT_DATA);
+#else
+	    m0 = m_getcl(MB_DONTWAIT, MT_DATA, M_PKTHDR);
 #endif
-	    }
+
 	    if (accept
 #if defined(TULIP_COPY_RXDATA)
 		&& m0 != NULL
diff --git a/sys/dev/netif/fxp/if_fxp.c b/sys/dev/netif/fxp/if_fxp.c
index 41af282b06..8439036eb6 100644
--- a/sys/dev/netif/fxp/if_fxp.c
+++ b/sys/dev/netif/fxp/if_fxp.c
@@ -26,7 +26,7 @@
  * SUCH DAMAGE.
  *
  * $FreeBSD: src/sys/dev/fxp/if_fxp.c,v 1.110.2.30 2003/06/12 16:47:05 mux Exp $
- * $DragonFly: src/sys/dev/netif/fxp/if_fxp.c,v 1.28 2005/05/27 15:03:12 joerg Exp $
+ * $DragonFly: src/sys/dev/netif/fxp/if_fxp.c,v 1.29 2005/05/29 10:08:36 hsu Exp $
  */
 
 /*
@@ -1052,7 +1052,7 @@ fxp_start(struct ifnet *ifp)
 	 */
 	while (!ifq_is_empty(&ifp->if_snd) && sc->tx_queued < FXP_NTXCB - 1) {
 		struct mbuf *m, *mb_head;
-		int segment;
+		int segment, ntries = 0;
 
 		/*
 		 * Grab a packet to transmit. The packet is dequeued,
@@ -1091,23 +1091,16 @@ tbdinit:
 			 * mbuf chain first. Bail out if we can't get the
 			 * new buffers.
 			 */
-			MGETHDR(mn, MB_DONTWAIT, MT_DATA);
+			if (ntries > 0)
+				break;
+			mn = m_dup(mb_head, MB_DONTWAIT);
 			if (mn == NULL)
 				break;
-			if (mb_head->m_pkthdr.len > MHLEN) {
-				MCLGET(mn, MB_DONTWAIT);
-				if ((mn->m_flags & M_EXT) == 0) {
-					m_freem(mn);
-					break;
-				}
-			}
-			m_copydata(mb_head, 0, mb_head->m_pkthdr.len,
-			    mtod(mn, caddr_t));
-			mn->m_pkthdr.len = mn->m_len = mb_head->m_pkthdr.len;
 			 /* We can transmit the packet, dequeue it. */
 			mb_head = ifq_dequeue(&ifp->if_snd);
 			m_freem(mb_head);
 			mb_head = mn;
+			ntries = 1;
 			goto tbdinit;
 		} else {
 			/* Nothing to worry about, just dequeue. */
diff --git a/sys/kern/uipc_mbuf.c b/sys/kern/uipc_mbuf.c
index f01cc34f22..4c994bb378 100644
--- a/sys/kern/uipc_mbuf.c
+++ b/sys/kern/uipc_mbuf.c
@@ -82,7 +82,7 @@
  *
  * @(#)uipc_mbuf.c	8.2 (Berkeley) 1/4/94
  * $FreeBSD: src/sys/kern/uipc_mbuf.c,v 1.51.2.24 2003/04/15 06:59:29 silby Exp $
- * $DragonFly: src/sys/kern/uipc_mbuf.c,v 1.36 2005/04/20 21:37:06 hsu Exp $
+ * $DragonFly: src/sys/kern/uipc_mbuf.c,v 1.37 2005/05/29 10:08:36 hsu Exp $
  */
 
 #include "opt_param.h"
@@ -830,70 +830,55 @@ m_getcl(int how, short type, int flags)
 }
 
 /*
- * struct mbuf *
- * m_getm(m, len, how, type)
- *
- * This will allocate len-worth of mbufs and/or mbuf clusters (whatever fits
- * best) and return a pointer to the top of the allocated chain. If m is
+ * Allocate chain of requested length.
+ */
+struct mbuf *
+m_getc(int len, int how, int type)
+{
+	struct mbuf *n, *nfirst = NULL, **ntail = &nfirst;
+	int nsize;
+
+	while (len > 0) {
+		n = m_getl(len, how, type, 0, &nsize);
+		if (n == NULL)
+			goto failed;
+		n->m_len = 0;
+		*ntail = n;
+		ntail = &n->m_next;
+		len -= nsize;
+	}
+	return (nfirst);
+
+failed:
+	m_freem(nfirst);
+	return (NULL);
+}
+
+/*
+ * Allocate len-worth of mbufs and/or mbuf clusters (whatever fits best)
+ * and return a pointer to the head of the allocated chain. If m0 is
  * non-null, then we assume that it is a single mbuf or an mbuf chain to
  * which we want len bytes worth of mbufs and/or clusters attached, and so
- * if we succeed in allocating it, we will just return a pointer to m.
+ * if we succeed in allocating it, we will just return a pointer to m0.
  *
  * If we happen to fail at any point during the allocation, we will free
  * up everything we have already allocated and return NULL.
  *
+ * Deprecated.  Use m_getc() and m_cat() instead.
  */
 struct mbuf *
-m_getm(struct mbuf *m, int len, int how, int type)
+m_getm(struct mbuf *m0, int len, int how, int type)
 {
-	struct mbuf *top, *tail, *mp, *mtail = NULL;
-
-	KASSERT(len >= 0, ("len is < 0 in m_getm"));
-
-	mp = m_get(how, type);
-	if (mp == NULL) {
-		return (NULL);
-	} else if (len > MINCLSIZE) {
-		m_mclget(mp, how);
-		if ((mp->m_flags & M_EXT) == 0) {
-			m_free(mp);
-			return (NULL);
-		}
-	}
-	mp->m_len = 0;
-	len -= M_TRAILINGSPACE(mp);
-
-	if (m != NULL) {
-		for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next)
-			;
-	} else {
-		m = mp;
-	}
-
-	top = tail = mp;
-	while (len > 0) {
-		mp = m_get(how, type);
-		if (mp == NULL)
-			goto failed;
+	struct mbuf *nfirst;
 
-		tail->m_next = mp;
-		tail = mp;
-		if (len > MINCLSIZE) {
-			m_mclget(mp, how);
-			if ((mp->m_flags & M_EXT) == 0)
-				goto failed;
-		}
+	nfirst = m_getc(len, how, type);
 
-		mp->m_len = 0;
-		len -= M_TRAILINGSPACE(mp);
+	if (m0 != NULL) {
+		m_last(m0)->m_next = nfirst;
+		return (m0);
 	}
 
-	if (mtail != NULL)
-		mtail->m_next = top;
-	return (m);
-failed:
-	m_freem(top);
-	return (NULL);
+	return (nfirst);
 }
 
 /*
@@ -1283,7 +1268,7 @@ m_dup(struct mbuf *m, int how)
 
 	/* Sanity check */
 	if (m == NULL)
-		return (0);
+		return (NULL);
 	KASSERT((m->m_flags & M_PKTHDR) != 0, ("%s: !PKTHDR", __func__));
 
 	/* While there's more data, get a new mbuf, tack it on, and fill it */
@@ -1294,30 +1279,20 @@ m_dup(struct mbuf *m, int how)
 		struct mbuf *n;
 
 		/* Get the next new mbuf */
-		MGET(n, how, m->m_type);
+		n = m_getl(remain, how, m->m_type, top == NULL ? M_PKTHDR : 0,
+			   &nsize);
 		if (n == NULL)
 			goto nospace;
-		if (top == NULL) {		/* first one, must be PKTHDR */
+		if (top == NULL)
 			if (!m_dup_pkthdr(n, m, how))
-				goto nospace;
-			nsize = MHLEN;
-		} else				/* not the first one */
-			nsize = MLEN;
-		if (remain >= MINCLSIZE) {
-			MCLGET(n, how);
-			if ((n->m_flags & M_EXT) == 0) {
-				(void)m_free(n);
-				goto nospace;
-			}
-			nsize = MCLBYTES;
-		}
-		n->m_len = 0;
+				goto nospace0;
 
 		/* Link it into the new chain */
 		*p = n;
 		p = &n->m_next;
 
 		/* Copy data from original mbuf(s) into new mbuf */
+		n->m_len = 0;
 		while (n->m_len < nsize && m != NULL) {
 			int chunk = min(nsize - n->m_len, m->m_len - moff);
 
@@ -1333,14 +1308,15 @@ m_dup(struct mbuf *m, int how)
 
 		/* Check correct total mbuf length */
 		KASSERT((remain > 0 && m != NULL) || (remain == 0 && m == NULL),
-		    	("%s: bogus m_pkthdr.len", __func__));
+			("%s: bogus m_pkthdr.len", __func__));
 	}
 	return (top);
 
 nospace:
 	m_freem(top);
-	MCFail++;
-	return (0);
+nospace0:
+	mbstat.m_mcfail++;
+	return (NULL);
 }
 
 /*
@@ -1351,8 +1327,7 @@ nospace:
 void
 m_cat(struct mbuf *m, struct mbuf *n)
 {
-	while (m->m_next)
-		m = m->m_next;
+	m = m_last(m);
 	while (n) {
 		if (m->m_flags & M_EXT ||
 		    m->m_data + m->m_len + n->m_len >= &m->m_dat[MLEN]) {
@@ -1573,71 +1548,47 @@ extpacket:
 	m->m_next = 0;
 	return (n);
 }
+
 /*
  * Routine to copy from device local memory into mbufs.
+ * Note: "offset" is ill-defined and always called as 0, so ignore it.
  */
 struct mbuf *
-m_devget(char *buf, int totlen, int off0, struct ifnet *ifp, 
-	void (*copy) (char *from, caddr_t to, u_int len))
+m_devget(char *buf, int len, int offset, struct ifnet *ifp,
+    void (*copy)(volatile const void *from, volatile void *to, size_t length))
 {
-	struct mbuf *m;
-	struct mbuf *top = 0, **mp = &top;
-	int off = off0, len;
-	char *cp;
-	char *epkt;
-
-	cp = buf;
-	epkt = cp + totlen;
-	if (off) {
-		cp += off + 2 * sizeof(u_short);
-		totlen -= 2 * sizeof(u_short);
-	}
-	MGETHDR(m, MB_DONTWAIT, MT_DATA);
-	if (m == 0)
-		return (0);
-	m->m_pkthdr.rcvif = ifp;
-	m->m_pkthdr.len = totlen;
-	m->m_len = MHLEN;
-
-	while (totlen > 0) {
-		if (top) {
-			MGET(m, MB_DONTWAIT, MT_DATA);
-			if (m == 0) {
-				m_freem(top);
-				return (0);
-			}
-			m->m_len = MLEN;
+	struct mbuf *m, *mfirst = NULL, **mtail;
+	int nsize, flags;
+
+	if (copy == NULL)
+		copy = bcopy;
+	mtail = &mfirst;
+	flags = M_PKTHDR;
+
+	while (len > 0) {
+		m = m_getl(len, MB_DONTWAIT, MT_DATA, flags, &nsize);
+		if (m == NULL) {
+			m_freem(mfirst);
+			return (NULL);
 		}
-		len = min(totlen, epkt - cp);
-		if (len >= MINCLSIZE) {
-			MCLGET(m, MB_DONTWAIT);
-			if (m->m_flags & M_EXT)
-				m->m_len = len = min(len, MCLBYTES);
-			else
-				len = m->m_len;
-		} else {
-			/*
-			 * Place initial small packet/header at end of mbuf.
-			 */
-			if (len < m->m_len) {
-				if (top == 0 && len + max_linkhdr <= m->m_len)
-					m->m_data += max_linkhdr;
-				m->m_len = len;
-			} else
-				len = m->m_len;
+		m->m_len = min(len, nsize);
+
+		if (flags & M_PKTHDR) {
+			if (len + max_linkhdr <= nsize)
+				m->m_data += max_linkhdr;
+			m->m_pkthdr.rcvif = ifp;
+			m->m_pkthdr.len = len;
+			flags = 0;
 		}
-		if (copy)
-			copy(cp, mtod(m, caddr_t), (unsigned)len);
-		else
-			bcopy(cp, mtod(m, caddr_t), (unsigned)len);
-		cp += len;
-		*mp = m;
-		mp = &m->m_next;
-		totlen -= len;
-		if (cp == epkt)
-			cp = buf;
+
+		copy(buf, m->m_data, (unsigned)m->m_len);
+		buf += m->m_len;
+		len -= m->m_len;
+		*mtail = m;
+		mtail = &m->m_next;
 	}
-	return (top);
+
+	return (mfirst);
 }
 
 /*
@@ -1886,6 +1837,14 @@ failed:
 	return (NULL);
 }
 
+struct mbuf *
+m_last(struct mbuf *m)
+{
+	while (m->m_next)
+		m = m->m_next;
+	return (m);
+}
+
 /*
  * Return the number of bytes in an mbuf chain.
  * If lastm is not NULL, also return the last mbuf.
diff --git a/sys/kern/uipc_mbuf2.c b/sys/kern/uipc_mbuf2.c
index aa9701987b..9e260d8a8c 100644
--- a/sys/kern/uipc_mbuf2.c
+++ b/sys/kern/uipc_mbuf2.c
@@ -1,5 +1,5 @@
 /*	$FreeBSD: src/sys/kern/uipc_mbuf2.c,v 1.2.2.5 2003/01/23 21:06:44 sam Exp $	*/
-/*	$DragonFly: src/sys/kern/uipc_mbuf2.c,v 1.8 2004/07/31 07:52:48 dillon Exp $	*/
+/*	$DragonFly: src/sys/kern/uipc_mbuf2.c,v 1.9 2005/05/29 10:08:36 hsu Exp $	*/
 /*	$KAME: uipc_mbuf2.c,v 1.31 2001/11/28 11:08:53 itojun Exp $	*/
 /*	$NetBSD: uipc_mbuf.c,v 1.40 1999/04/01 00:23:25 thorpej Exp $	*/
 
@@ -208,14 +208,7 @@ m_pulldown(m, off, len, offp)
 	 * now, we need to do the hard way.  don't m_copy as there's no room
 	 * on both end.
 	 */
-	MGET(o, MB_DONTWAIT, m->m_type);
-	if (o && len > MLEN) {
-		MCLGET(o, MB_DONTWAIT);
-		if ((o->m_flags & M_EXT) == 0) {
-			m_free(o);
-			o = NULL;
-		}
-	}
+	o = m_getl(len, MB_DONTWAIT, m->m_type, 0, NULL);
 	if (!o) {
 		m_freem(m);
 		return NULL;	/* ENOBUFS */
@@ -256,31 +249,13 @@ m_dup1(m, off, len, wait)
 	int wait;
 {
 	struct mbuf *n;
-	int l;
-	int copyhdr;
 
 	if (len > MCLBYTES)
 		return NULL;
-	if (off == 0 && (m->m_flags & M_PKTHDR) != 0) {
-		copyhdr = 1;
-		MGETHDR(n, wait, m->m_type);
-		l = MHLEN;
-	} else {
-		copyhdr = 0;
-		MGET(n, wait, m->m_type);
-		l = MLEN;
-	}
-	if (n && len > l) {
-		MCLGET(n, wait);
-		if ((n->m_flags & M_EXT) == 0) {
-			m_free(n);
-			n = NULL;
-		}
-	}
+	n = m_getl(len, wait, m->m_type, m->m_flags, NULL);
 	if (!n)
 		return NULL;
-
-	if (copyhdr && !m_dup_pkthdr(n, m, wait)) {
+	if (off == 0 && (m->m_flags & M_PKTHDR) && !m_dup_pkthdr(n, m, wait)) {
 		m_free(n);
 		return NULL;
 	}
diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index 66fcc1e25c..0f9ef54c0e 100644
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -82,7 +82,7 @@
  *
  *	@(#)uipc_socket.c	8.3 (Berkeley) 4/15/94
  * $FreeBSD: src/sys/kern/uipc_socket.c,v 1.68.2.24 2003/11/11 17:18:18 silby Exp $
- * $DragonFly: src/sys/kern/uipc_socket.c,v 1.29 2005/03/31 19:28:54 dillon Exp $
+ * $DragonFly: src/sys/kern/uipc_socket.c,v 1.30 2005/05/29 10:08:36 hsu Exp $
  */
 
 #include "opt_inet.h"
@@ -585,32 +585,14 @@ restart:
 			if (flags & MSG_EOR)
 				top->m_flags |= M_EOR;
 		    } else do {
-			if (top == 0) {
-				MGETHDR(m, MB_WAIT, MT_DATA);
-				if (m == NULL) {
-					error = ENOBUFS;
-					goto release;
-				}
-				mlen = MHLEN;
+			m = m_getl(resid, MB_WAIT, MT_DATA,
+				   top == NULL ? M_PKTHDR : 0, &mlen);
+			if (top == NULL) {
 				m->m_pkthdr.len = 0;
 				m->m_pkthdr.rcvif = (struct ifnet *)0;
-			} else {
-				MGET(m, MB_WAIT, MT_DATA);
-				if (m == NULL) {
-					error = ENOBUFS;
-					goto release;
-				}
-				mlen = MLEN;
 			}
-			if (resid >= MINCLSIZE) {
-				MCLGET(m, MB_WAIT);
-				if ((m->m_flags & M_EXT) == 0)
-					goto nopages;
-				mlen = MCLBYTES;
-				len = min(min(mlen, resid), space);
-			} else {
-nopages:
-				len = min(min(mlen, resid), space);
+			len = min(min(mlen, resid), space);
+			if (resid < MINCLSIZE) {
 				/*
 				 * For datagram protocols, leave room
 				 * for protocol headers in first mbuf.
diff --git a/sys/kern/uipc_socket2.c b/sys/kern/uipc_socket2.c
index 2dd6b0517c..d8cf8130f2 100644
--- a/sys/kern/uipc_socket2.c
+++ b/sys/kern/uipc_socket2.c
@@ -33,7 +33,7 @@
  *
  *	@(#)uipc_socket2.c	8.1 (Berkeley) 6/10/93
  * $FreeBSD: src/sys/kern/uipc_socket2.c,v 1.55.2.17 2002/08/31 19:04:55 dwmalone Exp $
- * $DragonFly: src/sys/kern/uipc_socket2.c,v 1.18 2005/04/20 21:37:06 hsu Exp $
+ * $DragonFly: src/sys/kern/uipc_socket2.c,v 1.19 2005/05/29 10:08:36 hsu Exp $
  */
 
 #include "opt_param.h"
@@ -880,23 +880,14 @@ sbcreatecontrol(p, size, type, level)
 	struct mbuf *m;
 
 	if (CMSG_SPACE((u_int)size) > MCLBYTES)
-		return ((struct mbuf *) NULL);
-	if ((m = m_get(MB_DONTWAIT, MT_CONTROL)) == NULL)
-		return ((struct mbuf *) NULL);
-	if (CMSG_SPACE((u_int)size) > MLEN) {
-		MCLGET(m, MB_DONTWAIT);
-		if ((m->m_flags & M_EXT) == 0) {
-			m_free(m);
-			return ((struct mbuf *) NULL);
-		}
-	}
+		return (NULL);
+	m = m_getl(CMSG_SPACE((u_int)size), MB_DONTWAIT, MT_CONTROL, 0, NULL);
+	if (m == NULL)
+		return (NULL);
+	m->m_len = CMSG_SPACE(size);
 	cp = mtod(m, struct cmsghdr *);
-	m->m_len = 0;
-	KASSERT(CMSG_SPACE((u_int)size) <= M_TRAILINGSPACE(m),
-	    ("sbcreatecontrol: short mbuf"));
 	if (p != NULL)
-		(void)memcpy(CMSG_DATA(cp), p, size);
-	m->m_len = CMSG_SPACE(size);
+		memcpy(CMSG_DATA(cp), p, size);
 	cp->cmsg_len = CMSG_LEN(size);
 	cp->cmsg_level = level;
 	cp->cmsg_type = type;
diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index 254792e720..a8f703a469 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -82,7 +82,7 @@
  *
  *	@(#)rtsock.c	8.7 (Berkeley) 10/12/95
  * $FreeBSD: src/sys/net/rtsock.c,v 1.44.2.11 2002/12/04 14:05:41 ru Exp $
- * $DragonFly: src/sys/net/rtsock.c,v 1.26 2005/05/25 01:44:16 dillon Exp $
+ * $DragonFly: src/sys/net/rtsock.c,v 1.27 2005/05/29 10:08:36 hsu Exp $
  */
 
 #include <sys/param.h>
@@ -765,16 +765,9 @@ rt_msg_mbuf(int type, struct rt_addrinfo *rtinfo)
 	hlen = rt_msghdrsize(type);
 	KASSERT(hlen <= MCLBYTES, ("rt_msg_mbuf: hlen %d doesn't fit", hlen));
 
-	m = m_gethdr(MB_DONTWAIT, MT_DATA);
+	m = m_getl(hlen, MB_DONTWAIT, MT_DATA, M_PKTHDR, NULL);
 	if (m == NULL)
 		return (NULL);
-	if (hlen > MHLEN) {
-		MCLGET(m, MB_DONTWAIT);
-		if (!(m->m_flags & M_EXT)) {
-			m_free(m);
-			return (NULL);
-		}
-	}
 	m->m_pkthdr.len = m->m_len = hlen;
 	m->m_pkthdr.rcvif = NULL;
 	rtinfo->rti_addrs = 0;
diff --git a/sys/netinet/tcp_output.c b/sys/netinet/tcp_output.c
index 9112212938..c3586ef683 100644
--- a/sys/netinet/tcp_output.c
+++ b/sys/netinet/tcp_output.c
@@ -82,7 +82,7 @@
  *
  *	@(#)tcp_output.c	8.4 (Berkeley) 5/24/95
  * $FreeBSD: src/sys/netinet/tcp_output.c,v 1.39.2.20 2003/01/29 22:45:36 hsu Exp $
- * $DragonFly: src/sys/netinet/tcp_output.c,v 1.28 2005/05/10 15:48:10 hsu Exp $
+ * $DragonFly: src/sys/netinet/tcp_output.c,v 1.29 2005/05/29 10:08:36 hsu Exp $
  */
 
 #include "opt_inet6.h"
@@ -681,21 +681,16 @@ send:
 		m->m_len += hdrlen;
 		m->m_data -= hdrlen;
 #else
-		MGETHDR(m, MB_DONTWAIT, MT_HEADER);
+#ifndef INET6
+		m = m_gethdr(MB_DONTWAIT, MT_HEADER);
+#else
+		m = m_getl(hdrlen + max_linkhdr, MB_DONTWAIT, MT_HEADER,
+			   M_PKTHDR, NULL);
+#endif
 		if (m == NULL) {
 			error = ENOBUFS;
 			goto out;
 		}
-#ifdef INET6
-		if (MHLEN < hdrlen + max_linkhdr) {
-			MCLGET(m, MB_DONTWAIT);
-			if (!(m->m_flags & M_EXT)) {
-				m_freem(m);
-				error = ENOBUFS;
-				goto out;
-			}
-		}
-#endif
 		m->m_data += max_linkhdr;
 		m->m_len = hdrlen;
 		if (len <= MHLEN - hdrlen - max_linkhdr) {
diff --git a/sys/sys/mbuf.h b/sys/sys/mbuf.h
index fd6e2e88b9..76fd073fc3 100644
--- a/sys/sys/mbuf.h
+++ b/sys/sys/mbuf.h
@@ -34,7 +34,7 @@
  *
  *	@(#)mbuf.h	8.5 (Berkeley) 2/19/95
  * $FreeBSD: src/sys/sys/mbuf.h,v 1.44.2.17 2003/04/15 06:15:02 silby Exp $
- * $DragonFly: src/sys/sys/mbuf.h,v 1.24 2005/04/20 21:37:06 hsu Exp $
+ * $DragonFly: src/sys/sys/mbuf.h,v 1.25 2005/05/29 10:08:36 hsu Exp $
  */
 
 #ifndef _SYS_MBUF_H_
@@ -339,6 +339,7 @@ struct mbstat {
 /*
  * MCLGET adds such clusters to a normal mbuf.  The flag M_EXT is set upon
  * success.
+ * Deprecated.  Use m_getcl() or m_getl() instead.
  */
 #define	MCLGET(m, how) do {						\
 	m_mclget((m), (how));						\
@@ -462,16 +463,18 @@ struct	mbuf	*m_copypacket(struct mbuf *, int);
 struct	mbuf	*m_defrag(struct mbuf *, int);
 struct	mbuf	*m_defrag_nofree(struct mbuf *, int);
 struct	mbuf	*m_devget(char *, int, int, struct ifnet *,
-		    void (*copy)(char *, caddr_t, u_int));
+		  void (*copy)(volatile const void *, volatile void *, size_t));
 struct	mbuf	*m_dup(struct mbuf *, int);
 int		 m_dup_pkthdr(struct mbuf *, const struct mbuf *, int);
 struct	mbuf	*m_free(struct mbuf *);
 void		 m_freem(struct mbuf *);
 struct	mbuf	*m_get(int, int);
+struct	mbuf    *m_getc(int len, int how, int type);
 struct  mbuf	*m_getcl(int how, short type, int flags);
 struct	mbuf	*m_getclr(int, int);
 struct	mbuf	*m_gethdr(int, int);
 struct	mbuf	*m_getm(struct mbuf *, int, int, int);
+struct	mbuf	*m_last(struct mbuf *m);
 u_int		 m_lengthm(struct mbuf *m, struct mbuf **lastm);
 void		 m_move_pkthdr(struct mbuf *, struct mbuf *);
 struct	mbuf	*m_prepend(struct mbuf *, int, int);
@@ -486,6 +489,29 @@ void		m_mclget(struct mbuf *m, int how);
 int		m_sharecount(struct mbuf *m);
 void		m_chtype(struct mbuf *m, int type);
 
+/*
+ * Allocate the right type of mbuf for the desired total length.
+ */
+static __inline struct mbuf *
+m_getl(int len, int how, int type, int flags, int *psize)
+{
+	struct mbuf *m;
+	int size;
+
+	if (len >= MINCLSIZE) {
+		m = m_getcl(how, type, flags);
+		size = MCLBYTES;
+	} else if (flags & M_PKTHDR) {
+		m = m_gethdr(how, type);
+		size = MHLEN;
+	} else {
+		m = m_get(how, type);
+		size = MLEN;
+	}
+	if (psize != NULL)
+		*psize = size;
+	return (m);
+}
 
 /*
  * Packets may have annotations attached by affixing a list
diff --git a/sys/vfs/nfs/krpc_subr.c b/sys/vfs/nfs/krpc_subr.c
index 876adfa2f5..30f08ab470 100644
--- a/sys/vfs/nfs/krpc_subr.c
+++ b/sys/vfs/nfs/krpc_subr.c
@@ -1,6 +1,6 @@
 /*	$NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd Exp $	*/
 /* $FreeBSD: src/sys/nfs/krpc_subr.c,v 1.13.2.1 2000/11/20 21:17:14 tegge Exp $	*/
-/* $DragonFly: src/sys/vfs/nfs/krpc_subr.c,v 1.6 2004/06/02 14:43:04 eirikn Exp $	*/
+/* $DragonFly: src/sys/vfs/nfs/krpc_subr.c,v 1.7 2005/05/29 10:08:36 hsu Exp $	*/
 
 /*
  * Copyright (c) 1995 Gordon Ross, Adam Glass
@@ -467,14 +467,7 @@ xdr_string_encode(char *str, int len)
 	if (mlen > MCLBYTES)		/* If too big, we just can't do it. */
 		return (NULL);
 
-	m = m_get(MB_WAIT, MT_DATA);
-	if (mlen > MLEN) {
-		MCLGET(m, MB_WAIT);
-		if ((m->m_flags & M_EXT) == 0) {
-			(void) m_free(m);	/* There can be only one. */
-			return (NULL);
-		}
-	}
+	m = m_getl(mlen, MB_WAIT, MT_DATA, 0, NULL);
 	xs = mtod(m, struct xdr_string *);
 	m->m_len = mlen;
 	xs->len = txdr_unsigned(len);
diff --git a/sys/vfs/nfs/nfs_serv.c b/sys/vfs/nfs/nfs_serv.c
index 14ac4192c9..318f5cfaec 100644
--- a/sys/vfs/nfs/nfs_serv.c
+++ b/sys/vfs/nfs/nfs_serv.c
@@ -35,7 +35,7 @@
  *
  *	@(#)nfs_serv.c  8.8 (Berkeley) 7/31/95
  * $FreeBSD: src/sys/nfs/nfs_serv.c,v 1.93.2.6 2002/12/29 18:19:53 dillon Exp $
- * $DragonFly: src/sys/vfs/nfs/nfs_serv.c,v 1.22 2004/12/29 02:41:26 dillon Exp $
+ * $DragonFly: src/sys/vfs/nfs/nfs_serv.c,v 1.23 2005/05/29 10:08:36 hsu Exp $
  */
 
 /*
@@ -646,9 +646,8 @@ nfsrv_readlink(struct nfsrv_descript *nfsd, struct nfssvc_sock *slp,
 	len = 0;
 	i = 0;
 	while (len < NFS_MAXPATHLEN) {
-		MGET(mp, MB_WAIT, MT_DATA);
-		MCLGET(mp, MB_WAIT);
-		mp->m_len = NFSMSIZ(mp);
+		mp = m_getcl(MB_WAIT, MT_DATA, 0);
+		mp->m_len = MCLBYTES;
 		if (len == 0)
 			mp3 = mp2 = mp;
 		else {
@@ -894,8 +893,7 @@ nfsrv_read(struct nfsrv_descript *nfsd, struct nfssvc_sock *slp,
 				i++;
 			}
 			if (left > 0) {
-				MGET(m, MB_WAIT, MT_DATA);
-				MCLGET(m, MB_WAIT);
+				m = m_getcl(MB_WAIT, MT_DATA, 0);
 				m->m_len = 0;
 				m2->m_next = m;
 				m2 = m;
diff --git a/sys/vfs/nfs/nfs_socket.c b/sys/vfs/nfs/nfs_socket.c
index bb8ab45d70..c0cb85f48f 100644
--- a/sys/vfs/nfs/nfs_socket.c
+++ b/sys/vfs/nfs/nfs_socket.c
@@ -35,7 +35,7 @@
  *
  *	@(#)nfs_socket.c	8.5 (Berkeley) 3/30/95
  * $FreeBSD: src/sys/nfs/nfs_socket.c,v 1.60.2.6 2003/03/26 01:44:46 alfred Exp $
- * $DragonFly: src/sys/vfs/nfs/nfs_socket.c,v 1.26 2005/03/31 19:28:57 dillon Exp $
+ * $DragonFly: src/sys/vfs/nfs/nfs_socket.c,v 1.27 2005/05/29 10:08:36 hsu Exp $
  */
 
 /*
@@ -1747,10 +1747,7 @@ nfs_realign(struct mbuf **pm, int hsiz)
 
 	while ((m = *pm) != NULL) {
 		if ((m->m_len & 0x3) || (mtod(m, intptr_t) & 0x3)) {
-			MGET(n, MB_WAIT, MT_DATA);
-			if (m->m_len >= MINCLSIZE) {
-				MCLGET(n, MB_WAIT);
-			}
+			n = m_getl(m->m_len, MB_WAIT, MT_DATA, 0, NULL);
 			n->m_len = 0;
 			break;
 		}
diff --git a/sys/vfs/nfs/nfs_subs.c b/sys/vfs/nfs/nfs_subs.c
index 1fe390387c..758c2bf064 100644
--- a/sys/vfs/nfs/nfs_subs.c
+++ b/sys/vfs/nfs/nfs_subs.c
@@ -35,7 +35,7 @@
  *
  *	@(#)nfs_subs.c  8.8 (Berkeley) 5/22/95
  * $FreeBSD: /repoman/r/ncvs/src/sys/nfsclient/nfs_subs.c,v 1.128 2004/04/14 23:23:55 peadar Exp $
- * $DragonFly: src/sys/vfs/nfs/nfs_subs.c,v 1.29 2005/04/20 17:01:54 dillon Exp $
+ * $DragonFly: src/sys/vfs/nfs/nfs_subs.c,v 1.30 2005/05/29 10:08:36 hsu Exp $
  */
 
 /*
@@ -586,9 +586,7 @@ nfsm_reqh(struct vnode *vp, u_long procid, int hsiz, caddr_t *bposp)
 	struct nfsmount *nmp;
 	int nqflag;
 
-	MGET(mb, MB_WAIT, MT_DATA);
-	if (hsiz >= MINCLSIZE)
-		MCLGET(mb, MB_WAIT);
+	mb = m_getl(hsiz, MB_WAIT, MT_DATA, 0, NULL);
 	mb->m_len = 0;
 	bpos = mtod(mb, caddr_t);
 
@@ -699,12 +697,10 @@ nfsm_rpchead(struct ucred *cr, int nmflag, int procid, int auth_type,
 		siz = auth_len;
 		while (siz > 0) {
 			if (M_TRAILINGSPACE(mb) == 0) {
-				MGET(mb2, MB_WAIT, MT_DATA);
-				if (siz >= MINCLSIZE)
-					MCLGET(mb2, MB_WAIT);
+				mb2 = m_getl(siz, MB_WAIT, MT_DATA, 0, NULL);
+				mb2->m_len = 0;
 				mb->m_next = mb2;
 				mb = mb2;
-				mb->m_len = 0;
 				bpos = mtod(mb, caddr_t);
 			}
 			i = min(siz, M_TRAILINGSPACE(mb));
@@ -732,12 +728,10 @@ nfsm_rpchead(struct ucred *cr, int nmflag, int procid, int auth_type,
 		siz = verf_len;
 		while (siz > 0) {
 			if (M_TRAILINGSPACE(mb) == 0) {
-				MGET(mb2, MB_WAIT, MT_DATA);
-				if (siz >= MINCLSIZE)
-					MCLGET(mb2, MB_WAIT);
+				mb2 = m_getl(siz, MB_WAIT, MT_DATA, 0, NULL);
+				mb2->m_len = 0;
 				mb->m_next = mb2;
 				mb = mb2;
-				mb->m_len = 0;
 				bpos = mtod(mb, caddr_t);
 			}
 			i = min(siz, M_TRAILINGSPACE(mb));
@@ -844,7 +838,8 @@ nfsm_uiotombuf(struct uio *uiop, struct mbuf **mq, int siz, caddr_t *bpos)
 	char *uiocp;
 	struct mbuf *mp, *mp2;
 	int xfer, left, mlen;
-	int uiosiz, clflg, rem;
+	int uiosiz, rem;
+	boolean_t getcluster;
 	char *cp;
 
 #ifdef DIAGNOSTIC
@@ -852,11 +847,11 @@ nfsm_uiotombuf(struct uio *uiop, struct mbuf **mq, int siz, caddr_t *bpos)
 		panic("nfsm_uiotombuf: iovcnt != 1");
 #endif
 
-	if (siz > MLEN)		/* or should it >= MCLBYTES ?? */
-		clflg = 1;
+	if (siz >= MINCLSIZE)
+		getcluster = TRUE;
 	else
-		clflg = 0;
-	rem = nfsm_rndup(siz)-siz;
+		getcluster = FALSE;
+	rem = nfsm_rndup(siz) - siz;
 	mp = mp2 = *mq;
 	while (siz > 0) {
 		left = uiop->uio_iov->iov_len;
@@ -867,9 +862,10 @@ nfsm_uiotombuf(struct uio *uiop, struct mbuf **mq, int siz, caddr_t *bpos)
 		while (left > 0) {
 			mlen = M_TRAILINGSPACE(mp);
 			if (mlen == 0) {
-				MGET(mp, MB_WAIT, MT_DATA);
-				if (clflg)
-					MCLGET(mp, MB_WAIT);
+				if (getcluster)
+					mp = m_getcl(MB_WAIT, MT_DATA, 0);
+				else
+					mp = m_get(MB_WAIT, MT_DATA);
 				mp->m_len = 0;
 				mp2->m_next = mp;
 				mp2 = mp;
@@ -1028,10 +1024,10 @@ nfsm_strtmbuf(struct mbuf **mb, char **bpos, const char *cp, long siz)
 	}
 	/* Loop around adding mbufs */
 	while (siz > 0) {
-		MGET(m1, MB_WAIT, MT_DATA);
-		if (siz > MLEN)
-			MCLGET(m1, MB_WAIT);
-		m1->m_len = NFSMSIZ(m1);
+		int msize;
+
+		m1 = m_getl(siz, MB_WAIT, MT_DATA, 0, &msize);
+		m1->m_len = msize;
 		m2->m_next = m1;
 		m2 = m1;
 		tl = mtod(m1, u_int32_t *);
diff --git a/sys/vfs/nfs/nfsm_subs.h b/sys/vfs/nfs/nfsm_subs.h
index be394ebd19..592208e7f1 100644
--- a/sys/vfs/nfs/nfsm_subs.h
+++ b/sys/vfs/nfs/nfsm_subs.h
@@ -35,7 +35,7 @@
  *
  *	@(#)nfsm_subs.h	8.2 (Berkeley) 3/30/95
  * $FreeBSD: src/sys/nfs/nfsm_subs.h,v 1.27.2.1 2000/10/28 16:27:27 dwmalone Exp $
- * $DragonFly: src/sys/vfs/nfs/nfsm_subs.h,v 1.7 2005/03/17 17:28:46 dillon Exp $
+ * $DragonFly: src/sys/vfs/nfs/nfsm_subs.h,v 1.8 2005/05/29 10:08:36 hsu Exp $
  */
 
 
@@ -503,9 +503,8 @@ struct mbuf *nfsm_rpchead (struct ucred *cr, int nmflag, int procid,
 		if (bp >= be) { \
 			if (mp == mb) \
 				mp->m_len += bp-bpos; \
-			MGET(mp, MB_WAIT, MT_DATA); \
-			MCLGET(mp, MB_WAIT); \
-			mp->m_len = NFSMSIZ(mp); \
+			mp = m_getcl(MB_WAIT, MT_DATA, 0); \
+			mp->m_len = MCLBYTES; \
 			mp2->m_next = mp; \
 			mp2 = mp; \
 			bp = mtod(mp, caddr_t); \