3 files changed, 70 insertions, 28 deletions

diff --git a/sys/kern/uipc_mbuf.c b/sys/kern/uipc_mbuf.c
index ff174e35a283..c8cf25c40fad 100644
--- a/sys/kern/uipc_mbuf.c
+++ b/sys/kern/uipc_mbuf.c
@@ -463,7 +463,7 @@ m_reclaim(void)
 
 /*
  * Space allocation routines.
- * These are also available as macros
+ * Some of these are also available as macros
  * for critical paths.
  */
 struct mbuf *
@@ -505,6 +505,72 @@ m_free(struct mbuf *m)
 	return (n);
 }
 
+/*
+ * 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
+ * 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 happen to fail at any point during the allocation, we will free
+ * up everything we have already allocated and return NULL.
+ *
+ */
+struct mbuf *
+m_getm(struct mbuf *m, int len, int how, int type)
+{
+	struct mbuf *top, *tail, *mp, *mtail = NULL;
+
+	KASSERT(len >= 0, ("len is < 0 in m_getm"));
+
+	MGET(mp, type, how);
+	if (mp == NULL)
+		return (NULL);
+	else if (len > MINCLSIZE) {
+		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) {
+		MGET(mp, type, how);
+		if (mp == NULL)
+			goto failed;
+
+		tail->m_next = mp;
+		tail = mp;
+		if (len > MINCLSIZE) {
+			MCLGET(mp, how);
+			if ((mp->m_flags & M_EXT) == 0)
+				goto failed;
+		}
+
+		mp->m_len = 0;
+		len -= M_TRAILINGSPACE(mp);
+	}
+
+	if (mtail != NULL)
+		mtail->m_next = top;
+	return (m);
+
+failed:
+	m_freem(top);
+	return (NULL);
+}
+
 void
 m_freem(struct mbuf *m)
 {
diff --git a/sys/netncp/ncp_rq.c b/sys/netncp/ncp_rq.c
index e661f5edda82..dacdee0cc615 100644
--- a/sys/netncp/ncp_rq.c
+++ b/sys/netncp/ncp_rq.c
@@ -46,8 +46,6 @@
 #include <netncp/ncp_ncp.h>
 #include <netncp/ncp_nls.h>
 
-static struct mbuf* m_getm(struct mbuf *top, int len);
-
 int
 ncp_rq_head(struct ncp_rq *rqp, u_int32_t ptype, u_int8_t fn,struct proc *p,
     struct ucred *cred)
@@ -98,29 +96,6 @@ ncp_rq_done(struct ncp_rq *rqp) {
 	return (0);
 }
 
-static struct mbuf*
-m_getm(struct mbuf *top, int len) {
-	int rest = len, mlen;
-	struct mbuf *m=0,*mp;
-	
-	mp = top;
-	while (rest > 0) {
-/*	NCPSDEBUG("%d\n",rest);*/
-		m = m_get(M_TRYWAIT, MT_DATA);
-		if (rest > MINCLSIZE) {
-			MCLGET(m,M_TRYWAIT);
-			mlen = ( (m->m_flags & M_EXT) == 0) ? MLEN : MCLBYTES;
-		} else { 
-			mlen = MLEN;
-		}
-		m->m_len = 0/*min(mlen,rest)*/;
-		mp->m_next = m;
-		mp = m;
-		rest -= mlen;
-	}
-	return top;
-}
-
 /*
  * Routines to fill the request
  */
@@ -182,7 +157,7 @@ ncp_rq_pathstring(struct ncp_rq *rqp, int size, char *name, struct ncp_nlstables
 		m->m_len += cplen;
 	}
 	if (size) {
-		m_getm(m, size);
+		m = m_getm(m, size, MT_DATA, M_TRYWAIT);
 		while (size > 0){
 			m = m->m_next;
 			cplen = min(size, M_TRAILINGSPACE(m));
@@ -215,7 +190,7 @@ ncp_rq_putanymem(struct ncp_rq *rqp, caddr_t source, int size, int type) {
 		m->m_len += cplen;
 	}
 	if (size) {
-		m_getm(m, size);
+		m = m_getm(m, size, MT_DATA, M_TRYWAIT);
 		while (size > 0){
 			m = m->m_next;
 			cplen = min(size, M_TRAILINGSPACE(m));
diff --git a/sys/sys/mbuf.h b/sys/sys/mbuf.h
index 316c018eae7d..2ea81b030eb8 100644
--- a/sys/sys/mbuf.h
+++ b/sys/sys/mbuf.h
@@ -665,6 +665,7 @@ struct	mbuf *m_dup(struct mbuf *, int);
 struct	mbuf *m_free(struct mbuf *);
 void	m_freem(struct mbuf *);
 struct	mbuf *m_get(int, int);
+struct	mbuf *m_getm(struct mbuf *, int, int, int);
 struct	mbuf *m_getclr(int, int);
 struct	mbuf *m_gethdr(int, int);
 int	m_mballoc(int, int);