svn commit: r335133 - head/sys/netinet/libalias

[Andrey V. Elsukov]

Author: ae
Date: Thu Jun 14 11:15:39 2018
New Revision: 335133
URL: https://svnweb.freebsd.org/changeset/base/335133

Log:
  In m_megapullup() use m_getjcl() to allocate 9k or 16k mbuf when requested.
  
  It is better to try allocate a big mbuf, than just silently drop a big
  packet. A better solution could be reworking of libalias modules to be
  able use m_copydata()/m_copyback() instead of requiring the single
  contiguous buffer.
  
  PR:		229006
  MFC after:	1 week

Modified:
  head/sys/netinet/libalias/alias.c

Modified: head/sys/netinet/libalias/alias.c
==============================================================================
--- head/sys/netinet/libalias/alias.c	Thu Jun 14 11:09:51 2018	(r335132)
+++ head/sys/netinet/libalias/alias.c	Thu Jun 14 11:15:39 2018	(r335133)
@@ -1751,7 +1751,8 @@ LibAliasUnLoadAllModule(void)
  * the input packet, on failure NULL. The input packet is always consumed.
  */
 struct mbuf *
-m_megapullup(struct mbuf *m, int len) {
+m_megapullup(struct mbuf *m, int len)
+{
 	struct mbuf *mcl;
 
 	if (len > m->m_pkthdr.len)
@@ -1760,7 +1761,14 @@ m_megapullup(struct mbuf *m, int len) {
 	if (m->m_next == NULL && M_WRITABLE(m))
 		return (m);
 
-	mcl = m_get2(len, M_NOWAIT, MT_DATA, M_PKTHDR);
+	if (len <= MJUMPAGESIZE)
+		mcl = m_get2(len, M_NOWAIT, MT_DATA, M_PKTHDR);
+	else if (len <= MJUM9BYTES)
+		mcl = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUM9BYTES);
+	else if (len <= MJUM16BYTES)
+		mcl = m_getjcl(M_NOWAIT, MT_DATA, M_PKTHDR, MJUM16BYTES);
+	else
+		goto bad;
 	if (mcl == NULL)
 		goto bad;
 	m_align(mcl, len);