svn commit: r250700 - in head/sys: conf net netinet6 sys

Thu May 16 16:20:19 UTC 2013

Author: julian
Date: Thu May 16 16:20:17 2013
New Revision: 250700
URL: http://svnweb.freebsd.org/changeset/base/250700

Log:
  Finally change the mbuf to have its own fib field instead of stealing
  4 flag bits. This was supposed to happen in 8.0, and again in 2012..
  
  MFC after:	never

Modified:
  head/sys/conf/NOTES
  head/sys/net/route.c
  head/sys/netinet6/ip6_output.c
  head/sys/sys/mbuf.h

Modified: head/sys/conf/NOTES
==============================================================================

--- head/sys/conf/NOTES	Thu May 16 15:28:38 2013	(r250699)
+++ head/sys/conf/NOTES	Thu May 16 16:20:17 2013	(r250700)
@@ -571,7 +571,8 @@ options 	HWPMC_HOOKS		# Other necessary 
 options 	INET			#Internet communications protocols
 options 	INET6			#IPv6 communications protocols
 
-options 	ROUTETABLES=2		# max 16. 1 is back compatible.
+options 	ROUTETABLES=2		# allocated fibs up to 65536. default is 1.
+					# but that would be a bad idea as they are large.
 
 options 	TCP_OFFLOAD		# TCP offload support.
 

Modified: head/sys/net/route.c
==============================================================================
--- head/sys/net/route.c	Thu May 16 15:28:38 2013	(r250699)
+++ head/sys/net/route.c	Thu May 16 16:20:17 2013	(r250700)
@@ -68,8 +68,7 @@
 
 #include <vm/uma.h>
 
-/* We use 4 bits in the mbuf flags, thus we are limited to 16 FIBS. */
-#define	RT_MAXFIBS	16
+#define	RT_MAXFIBS	UINT16_MAX
 
 /* Kernel config default option. */
 #ifdef ROUTETABLES
@@ -86,17 +85,10 @@
 #define	RT_NUMFIBS	1
 #endif
 
+/* This is read-only.. */
 u_int rt_numfibs = RT_NUMFIBS;
 SYSCTL_UINT(_net, OID_AUTO, fibs, CTLFLAG_RD, &rt_numfibs, 0, "");
-/*
- * Allow the boot code to allow LESS than RT_MAXFIBS to be used.
- * We can't do more because storage is statically allocated for now.
- * (for compatibility reasons.. this will change. When this changes, code should
- * be refactored to protocol independent parts and protocol dependent parts,
- * probably hanging of domain(9) specific storage to not need the full
- * fib * af RNH allocation etc. but allow tuning the number of tables per
- * address family).
- */
+/* and this can be set too big but will be fixed before it is used */
 TUNABLE_INT("net.fibs", &rt_numfibs);
 
 /*

Modified: head/sys/netinet6/ip6_output.c
==============================================================================
--- head/sys/netinet6/ip6_output.c	Thu May 16 15:28:38 2013	(r250699)
+++ head/sys/netinet6/ip6_output.c	Thu May 16 16:20:17 2013	(r250700)
@@ -1126,7 +1126,7 @@ passout:
 				IP6STAT_INC(ip6s_odropped);
 				goto sendorfree;
 			}
-			m->m_flags = m0->m_flags & M_COPYFLAGS;	/* incl. FIB */
+			m->m_flags = m0->m_flags & M_COPYFLAGS;
 			*mnext = m;
 			mnext = &m->m_nextpkt;
 			m->m_data += max_linkhdr;
@@ -1152,6 +1152,7 @@ passout:
 			}
 			m_cat(m, m_frgpart);
 			m->m_pkthdr.len = len + hlen + sizeof(*ip6f);
+			m->m_pkthdr.fibnum = m0->m_pkthdr.fibnum;
 			m->m_pkthdr.rcvif = NULL;
 			ip6f->ip6f_reserved = 0;
 			ip6f->ip6f_ident = id;

Modified: head/sys/sys/mbuf.h
==============================================================================
--- head/sys/sys/mbuf.h	Thu May 16 15:28:38 2013	(r250699)
+++ head/sys/sys/mbuf.h	Thu May 16 16:20:17 2013	(r250700)
@@ -129,6 +129,8 @@ struct pkthdr {
 		u_int16_t vt_vtag;	/* Ethernet 802.1p+q vlan tag */
 		u_int16_t vt_nrecs;	/* # of IGMPv3 records in this chain */
 	} PH_vt;
+	u_int16_t	 fibnum;	/* this packet should use this fib */
+	u_int16_t	 pad2;		/* align to 32 bits */
 	SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
 };
 #define ether_vtag	PH_vt.vt_vtag
@@ -171,6 +173,7 @@ struct mbuf {
 #define	m_type		m_hdr.mh_type
 #define	m_flags		m_hdr.mh_flags
 #define	m_nextpkt	m_hdr.mh_nextpkt
+#define	m_fibnum	m_hdr.mh_nextpkt
 #define	m_act		m_nextpkt
 #define	m_pkthdr	M_dat.MH.MH_pkthdr
 #define	m_ext		M_dat.MH.MH_dat.MH_ext
@@ -205,12 +208,6 @@ struct mbuf {
 #define	M_FLOWID	0x00400000 /* deprecated: flowid is valid */
 #define	M_HASHTYPEBITS	0x0F000000 /* mask of bits holding flowid hash type */
 
-/*
- * For RELENG_{6,7} steal these flags for limited multiple routing table
- * support. In RELENG_8 and beyond, use just one flag and a tag.
- */
-#define	M_FIB		0xF0000000 /* steal some bits to store fib number. */
-
 #define	M_NOTIFICATION	M_PROTO5    /* SCTP notification */
 
 /*
@@ -258,7 +255,7 @@ struct mbuf {
  */
 #define	M_COPYFLAGS \
     (M_PKTHDR|M_EOR|M_RDONLY|M_PROTOFLAGS|M_SKIP_FIREWALL|M_BCAST|M_MCAST|\
-     M_FRAG|M_FIRSTFRAG|M_LASTFRAG|M_VLANTAG|M_PROMISC|M_FIB|M_HASHTYPEBITS)
+     M_FRAG|M_FIRSTFRAG|M_LASTFRAG|M_VLANTAG|M_PROMISC|M_HASHTYPEBITS)
 
 /*
  * External buffer types: identify ext_buf type.
@@ -1010,17 +1007,18 @@ m_tag_find(struct mbuf *m, int type, str
 	    m_tag_locate(m, MTAG_ABI_COMPAT, type, start));
 }
 
-/* XXX temporary FIB methods probably eventually use tags.*/
-#define M_FIBSHIFT    28
-#define M_FIBMASK	0x0F
-
-/* get the fib from an mbuf and if it is not set, return the default */
-#define M_GETFIB(_m) \
-    ((((_m)->m_flags & M_FIB) >> M_FIBSHIFT) & M_FIBMASK)
+static int inline
+rt_m_getfib(struct mbuf *m)
+{
+	KASSERT(m->m_flags & M_EXT , ("attempt to set FIB on non header mbuf"));
+	return (m->m_pkthdr.fibnum);
+}
+
+#define M_GETFIB(_m)   rt_m_getfib(_m)
 
 #define M_SETFIB(_m, _fib) do {						\
-	_m->m_flags &= ~M_FIB;					   	\
-	_m->m_flags |= (((_fib) << M_FIBSHIFT) & M_FIB);  \
+        KASSERT((_m)->m_flags & M_EXT, ("No FIB on non header mbuf"));	\
+	((_m)->m_pkthdr.fibnum) = (_fib);				\
 } while (0)
 
 #endif /* _KERNEL */
