Introduce `pipexoutq' mbuf(9) queue, and put outgoing pipex(4) related

PPPOE packets within. Do (*if_output)() calls within netisr handler with
netlock held.

We can't predict netlock state when pipex(4) related (*if_qstart)()
handlers called. This means we can't use netlock within pppac_qstart()
and pppx_if_qstart() handlers.

ok bluhm@

diff --git a/sys/net/if.c b/sys/net/if.c
index c12943d..8a29aec 100644 (file)
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if.c,v 1.654 2022/06/27 15:11:23 jan Exp $    */
+/*     $OpenBSD: if.c,v 1.655 2022/06/28 08:01:40 mvs Exp $    */
 /*     $NetBSD: if.c,v 1.35 1996/05/07 05:26:04 thorpej Exp $  */
 
 /*
@@ -913,6 +913,10 @@ if_netisr(void *unused)
 #if NBRIDGE > 0
                if (n & (1 << NETISR_BRIDGE))
                        bridgeintr();
+#endif
+#ifdef PIPEX
+               if (n & (1 << NETISR_PIPEX))
+                       pipexintr();
 #endif
                t |= n;
        }

diff --git a/sys/net/netisr.h b/sys/net/netisr.h
index 6e90c27..6162963 100644 (file)
--- a/sys/net/netisr.h
+++ b/sys/net/netisr.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: netisr.h,v 1.56 2022/04/28 16:56:39 bluhm Exp $       */
+/*     $OpenBSD: netisr.h,v 1.57 2022/06/28 08:01:40 mvs Exp $ */
 /*     $NetBSD: netisr.h,v 1.12 1995/08/12 23:59:24 mycroft Exp $      */
 
 /*
@@ -45,6 +45,7 @@
 #define        NETISR_PFSYNC   5               /* for pfsync "immediate" tx */
 #define        NETISR_ARP      18              /* same as AF_LINK */
 #define        NETISR_IPV6     24              /* same as AF_INET6 */
+#define        NETISR_PIPEX    27              /* for pipex processing */
 #define        NETISR_PPP      28              /* for PPP processing */
 #define        NETISR_BRIDGE   29              /* for bridge processing */
 #define        NETISR_SWITCH   31              /* for switch dataplane */
@@ -65,6 +66,7 @@ void  pppintr(void);
 void   bridgeintr(void);
 void   switchintr(void);
 void   pfsyncintr(void);
+void   pipexintr(void);
 
 #define        schednetisr(anisr)                                              \
 do {                                                                   \

diff --git a/sys/net/pipex.c b/sys/net/pipex.c
index 393a7d5..7eef55f 100644 (file)
--- a/sys/net/pipex.c
+++ b/sys/net/pipex.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: pipex.c,v 1.141 2022/06/26 22:51:58 mvs Exp $ */
+/*     $OpenBSD: pipex.c,v 1.142 2022/06/28 08:01:40 mvs Exp $ */
 
 /*-
  * Copyright (c) 2009 Internet Initiative Japan Inc.
@@ -52,6 +52,7 @@
 #include <net/route.h>
 #include <net/ppp_defs.h>
 #include <net/ppp-comp.h>
+#include <net/netisr.h>
 
 #include "pf.h"
 #if NPF > 0
@@ -106,6 +107,9 @@ struct radix_node_head      *pipex_rd_head6 = NULL; /* [L] */
 struct timeout pipex_timer_ch;         /* callout timer context */
 int pipex_prune = 1;                   /* [I] walk list every seconds */
 
+struct mbuf_queue pipexoutq = MBUF_QUEUE_INITIALIZER(
+    IFQ_MAXLEN, IPL_SOFTNET);
+
 /* borrow an mbuf pkthdr field */
 #define ph_ppp_proto ether_vtag
 
@@ -193,6 +197,46 @@ pipex_ioctl(void *ownersc, u_long cmd, caddr_t data)
        return (ret);
 }
 
+/************************************************************************
+ * Software Interrupt Handler
+ ************************************************************************/
+
+void
+pipexintr(void)
+{
+       struct mbuf_list ml;
+       struct mbuf *m;
+       struct pipex_session *session;
+
+       NET_ASSERT_LOCKED();
+
+       mq_delist(&pipexoutq, &ml);
+
+       while ((m = ml_dequeue(&ml)) != NULL) {
+               struct ifnet *ifp;
+
+               session = m->m_pkthdr.ph_cookie;
+
+               ifp = if_get(session->proto.pppoe.over_ifidx);
+               if (ifp != NULL) {
+                       struct pipex_pppoe_header *pppoe;
+                       int len;
+
+                       pppoe = mtod(m, struct pipex_pppoe_header *);
+                       len = ntohs(pppoe->length);
+                       ifp->if_output(ifp, m, &session->peer.sa, NULL);
+                       counters_pkt(session->stat_counters, pxc_opackets,
+                           pxc_obytes, len);
+               } else {
+                       m_freem(m);
+                       counters_inc(session->stat_counters, pxc_oerrors);
+               }
+               if_put(ifp);
+
+               pipex_rele_session(session);
+       }
+}
+
 /************************************************************************
  * Session management functions
  ************************************************************************/
@@ -1259,7 +1303,6 @@ Static void
 pipex_pppoe_output(struct mbuf *m0, struct pipex_session *session)
 {
        struct pipex_pppoe_header *pppoe;
-       struct ifnet *ifp;
        int len, padlen;
 
        /* save length for pppoe header */
@@ -1286,18 +1329,15 @@ pipex_pppoe_output(struct mbuf *m0, struct pipex_session *session)
        pppoe->length = htons(len);
 
        m0->m_pkthdr.ph_ifidx = session->proto.pppoe.over_ifidx;
+       refcnt_take(&session->pxs_refcnt);
+       m0->m_pkthdr.ph_cookie = session;
        m0->m_flags &= ~(M_BCAST|M_MCAST);
 
-       ifp = if_get(session->proto.pppoe.over_ifidx);
-       if (ifp != NULL) {
-               ifp->if_output(ifp, m0, &session->peer.sa, NULL);
-               counters_pkt(session->stat_counters, pxc_opackets,
-                   pxc_obytes, len);
-       } else {
-               m_freem(m0);
+       if (mq_enqueue(&pipexoutq, m0) != 0) {
                counters_inc(session->stat_counters, pxc_oerrors);
-       }
-       if_put(ifp);
+               pipex_rele_session(session);
+       } else
+               schednetisr(NETISR_PIPEX);
 }
 #endif /* PIPEX_PPPOE */