Add new failure detection algorithm.

It works as follows:
In every 'interval' seconds defined links are checked.
If they are non-active they will not be used by to data transfer.

No response from:	julian, archie
Silent on:		net@
Approved by:		scottl (mentor)

2 files changed, 94 insertions, 1 deletions

diff --git a/sys/netgraph/ng_one2many.c b/sys/netgraph/ng_one2many.c
index 927bb77..a11a0b7 100644
--- a/sys/netgraph/ng_one2many.c
+++ b/sys/netgraph/ng_one2many.c
@@ -53,11 +53,17 @@
 #include <sys/malloc.h>
 #include <sys/ctype.h>
 #include <sys/mbuf.h>
+#include <sys/socket.h>
+#include <sys/sockio.h>
 #include <sys/errno.h>
 
+#include <net/if.h>
+#include <net/if_media.h>
+
 #include <netgraph/ng_message.h>
 #include <netgraph/netgraph.h>
 #include <netgraph/ng_parse.h>
+#include <netgraph/ng_ether.h>
 #include <netgraph/ng_one2many.h>
 
 /* Per-link private data */
@@ -74,6 +80,7 @@ struct ng_one2many_private {
 	u_int16_t			nextMany;	/* next round-robin */
 	u_int16_t			numActiveMany;	/* # active "many" */
 	u_int16_t			activeMany[NG_ONE2MANY_MAX_LINKS];
+	struct callout_handle		callout;
 };
 typedef struct ng_one2many_private *priv_p;
 
@@ -86,6 +93,8 @@ static ng_rcvdata_t	ng_one2many_rcvdata;
 static ng_disconnect_t	ng_one2many_disconnect;
 
 /* Other functions */
+static void		ng_one2many_scan(node_p node, hook_p hook __unused,
+			    void *arg1 __unused, int arg2 __unused);
 static void		ng_one2many_update_many(priv_p priv);
 
 /* Store each hook's link number in the private field */
@@ -195,9 +204,15 @@ ng_one2many_constructor(node_p node)
 		return (ENOMEM);
 	priv->conf.xmitAlg = NG_ONE2MANY_XMIT_ROUNDROBIN;
 	priv->conf.failAlg = NG_ONE2MANY_FAIL_MANUAL;
+	priv->conf.interval = 5;
 
 	NG_NODE_SET_PRIVATE(node, priv);
 
+	if (priv->conf.failAlg == NG_ONE2MANY_FAIL_IFACE_LINK) {
+		priv->callout = ng_timeout(node, NULL, priv->conf.interval * hz,
+		    ng_one2many_scan, NULL, 0);
+	}
+
 	/* Done */
 	return (0);
 }
@@ -286,6 +301,7 @@ ng_one2many_rcvmsg(node_p node, item_p item, hook_p lasthook)
 			}
 			switch (conf->failAlg) {
 			case NG_ONE2MANY_FAIL_MANUAL:
+			case NG_ONE2MANY_FAIL_IFACE_LINK:
 				break;
 			default:
 				error = EINVAL;
@@ -301,6 +317,13 @@ ng_one2many_rcvmsg(node_p node, item_p item, hook_p lasthook)
 			/* Copy config and reset */
 			bcopy(conf, &priv->conf, sizeof(*conf));
 			ng_one2many_update_many(priv);
+
+			ng_untimeout(priv->callout, node);
+			if (priv->conf.failAlg == NG_ONE2MANY_FAIL_IFACE_LINK) {
+				priv->callout = ng_timeout(node, NULL,
+				    priv->conf.interval * hz, ng_one2many_scan,
+				    NULL, 0);
+			}
 			break;
 		    }
 		case NGM_ONE2MANY_GET_CONFIG:
@@ -476,6 +499,8 @@ ng_one2many_shutdown(node_p node)
 
 	KASSERT(priv->numActiveMany == 0,
 	    ("%s: numActiveMany=%d", __func__, priv->numActiveMany));
+	if (priv->conf.failAlg == NG_ONE2MANY_FAIL_IFACE_LINK)
+		ng_untimeout(priv->callout, node);
 	FREE(priv, M_NETGRAPH);
 	NG_NODE_SET_PRIVATE(node, NULL);
 	NG_NODE_UNREF(node);
@@ -517,6 +542,63 @@ ng_one2many_disconnect(hook_p hook)
 		    	OTHER FUNCTIONS
 ******************************************************************/
 
+#if 0
+/*
+ * Get interface name.
+ */
+static const char *
+ng_one2many_ifname(struct ng_one2many_link *link)
+{
+	node_p node;
+
+	node = link->hook->hk_peer->hk_node;
+	if (strcmp(node->nd_type->name, "ether") != 0)
+		return ("unknown");
+	return (node->nd_name);
+}
+#endif
+
+/*
+ * Check if interface related to given node is active.
+ */
+static int
+ng_one2many_active(struct ng_one2many_link *link)
+{
+	struct ng_ether_private *ethpriv;
+	struct ifmediareq ifmr;
+	struct ifnet *ifp;
+	node_p node;
+	int error;
+
+	node = link->hook->hk_peer->hk_node;
+	if (strcmp(node->nd_type->name, "ether") != 0)
+		return (0);
+	ethpriv = NG_NODE_PRIVATE(node);
+	ifp = ethpriv->ifp;
+	bzero(&ifmr, sizeof(ifmr));
+	error = ifp->if_ioctl(ifp, SIOCGIFMEDIA, (char *)&ifmr);
+	if (error != 0)
+		return (0);
+	if ((ifmr.ifm_status & IFM_ACTIVE) == 0)
+		return (0);
+	return (1);
+}
+
+/*
+ * Check every priv->conf.interval seconds for active links.
+ */
+static void
+ng_one2many_scan(node_p node, hook_p hook __unused, void *arg1 __unused,
+    int arg2 __unused)
+{
+	const priv_p priv = NG_NODE_PRIVATE(node);
+
+	ng_one2many_update_many(priv);
+
+	priv->callout = ng_timeout(node, NULL, priv->conf.interval * hz,
+	    ng_one2many_scan, NULL, 0);
+}
+
 /*
  * Update internal state after the addition or removal of a "many" link
  */
@@ -536,6 +618,13 @@ ng_one2many_update_many(priv_p priv)
 				priv->numActiveMany++;
 			}
 			break;
+		case NG_ONE2MANY_FAIL_IFACE_LINK:
+			if (priv->many[linkNum].hook != NULL &&
+			    ng_one2many_active(&priv->many[linkNum])) {
+				priv->activeMany[priv->numActiveMany] = linkNum;
+				priv->numActiveMany++;
+			}
+			break;
 #ifdef INVARIANTS
 		default:
 			panic("%s: invalid failAlg", __func__);
diff --git a/sys/netgraph/ng_one2many.h b/sys/netgraph/ng_one2many.h
index bf79859..3f7ceec 100644
--- a/sys/netgraph/ng_one2many.h
+++ b/sys/netgraph/ng_one2many.h
@@ -61,13 +61,16 @@
 #define NG_ONE2MANY_XMIT_ROUNDROBIN	1	/* round-robin delivery */
 #define NG_ONE2MANY_XMIT_ALL		2	/* send packets to all many hooks */
 
-/* Algorithms for detecting link failure (XXX only one so far) */
+/* Algorithms for detecting link failure */
 #define NG_ONE2MANY_FAIL_MANUAL		1	/* use enabledLinks[] array */
+#define NG_ONE2MANY_FAIL_IFACE_LINK	2	/* use interface state */
 
 /* Node configuration structure */
 struct ng_one2many_config {
 	u_int32_t	xmitAlg;		/* how to distribute packets */
 	u_int32_t	failAlg;		/* how to detect link failure */
+	u_int32_t	interval;		/* interval for IFACE_LINK
+						   failure algorithm */
 	u_char		enabledLinks[NG_ONE2MANY_MAX_LINKS];
 };
 
@@ -75,6 +78,7 @@ struct ng_one2many_config {
 #define NG_ONE2MANY_CONFIG_TYPE_INFO(atype)	{		\
 	  { "xmitAlg",		&ng_parse_uint32_type	},	\
 	  { "failAlg",		&ng_parse_uint32_type	},	\
+	  { "interval",		&ng_parse_uint32_type	},	\
 	  { "enabledLinks",	(atype)			},	\
 	  { NULL }						\
 }