From: Philippe Gerum <r...@xenomai.org>
Signed-off-by: Philippe Gerum <r...@xenomai.org>
---
kernel/drivers/net/doc/README.routing | 22 ++++++++++
kernel/drivers/net/doc/README.rtnetproxy | 6 ++-
kernel/drivers/net/stack/ipv4/route.c | 54 +++++++++++++++++++++---
3 files changed, 75 insertions(+), 7 deletions(-)
diff --git a/kernel/drivers/net/doc/README.routing
b/kernel/drivers/net/doc/README.routing
index f59c3f3f5..674039f91 100644
--- a/kernel/drivers/net/doc/README.routing
+++ b/kernel/drivers/net/doc/README.routing
@@ -115,3 +115,25 @@ the hash-key-based lookup and a potential query of the
key-less list of routes.
RTnet provides by default a pool of 16 network routes. This number can be
modified in the source code (see ipv4/route.c). Network routes are only
manually added or removed via rtroute.
+
+4. Default gateway address
+--------------------------
+
+In some cases, it is desirable for the RTnet routing system to fall
+back to a default gateway address for otherwise unresolved
+routes. Typically, such a gateway comes in handy when a rtnetproxy
+device is required for sharing a single physical interface (NIC)
+between the real-time and regular traffic (accepting the implications
+this may have with respect to real-time performance). Both the regular
+and the RTnet routing configurations can define their respective
+default gateway, first to route regular traffic to the proxy, next to
+route such traffic via the gateway assigned to the default RTnet
+route.
+
+A default gateway can be defined by the rtroute command as follows:
+
+# rtroute add default gw <IP_ADDRESS>
+
+Support for the default gateway is available when
+CONFIG_XENO_DRIVERS_NET_RTIPV4_NETROUTING is enabled. A single default
+gateway address is supported.
diff --git a/kernel/drivers/net/doc/README.rtnetproxy
b/kernel/drivers/net/doc/README.rtnetproxy
index 647cdb6a9..7d115bbca 100644
--- a/kernel/drivers/net/doc/README.rtnetproxy
+++ b/kernel/drivers/net/doc/README.rtnetproxy
@@ -14,8 +14,10 @@ the network device is "rtproxy".
Setup:
--------
-Get your RTnet working first! All IP addresses you are interested in have
-to be set via "rtifconfig ethX route solicit IP_ADDRESS"!
+Get your RTnet working first! All IP addresses you are interested in
+have to be set via "rtifconfig ethX route solicit IP_ADDRESS", or a
+default gateway machine should have been set via "rtroute add default
+gw IP_ADDRESS".
insmod rtnetproxy.o
diff --git a/kernel/drivers/net/stack/ipv4/route.c
b/kernel/drivers/net/stack/ipv4/route.c
index 14a8b2932..e352e39fe 100644
--- a/kernel/drivers/net/stack/ipv4/route.c
+++ b/kernel/drivers/net/stack/ipv4/route.c
@@ -51,7 +51,7 @@ struct net_route {
u32 gw_ip;
};
-#if (CONFIG_XENO_DRIVERS_NET_RTIPV4_HOST_ROUTES &
\
+#if (CONFIG_XENO_DRIVERS_NET_RTIPV4_HOST_ROUTES & \
(CONFIG_XENO_DRIVERS_NET_RTIPV4_HOST_ROUTES - 1))
#error CONFIG_XENO_DRIVERS_NET_RTIPV4_HOST_ROUTES must be power of 2
#endif
@@ -88,6 +88,7 @@ static struct net_route *free_net_route;
static int allocated_net_routes;
static struct net_route *net_hash_tbl[NET_HASH_TBL_SIZE + 1];
static unsigned int net_hash_key_shift = NET_HASH_KEY_SHIFT;
+static u32 default_gw_ip;
static DEFINE_RTDM_LOCK(net_table_lock);
module_param(net_hash_key_shift, uint, 0444);
@@ -376,7 +377,15 @@ static int rtnet_ipv4_net_route_next(struct
xnvfile_snapshot_iterator *it,
struct rtnet_ipv4_net_route_data *p = data;
if (priv->entry_ptr == NULL) {
- if (++priv->key >= NET_HASH_TBL_SIZE + 1)
+ if (++priv->key == 0 && default_gw_ip != INADDR_ANY) {
+ p->key = NET_HASH_TBL_SIZE;
+ p->dest_net_ip = INADDR_ANY;
+ p->dest_net_mask = INADDR_ANY;
+ p->gw_ip = default_gw_ip;
+ return 1;
+ }
+
+ if (priv->key >= NET_HASH_TBL_SIZE + 1)
return 0;
priv->entry_ptr = net_hash_tbl[priv->key];
@@ -410,12 +419,16 @@ static int rtnet_ipv4_net_route_show(struct
xnvfile_snapshot_iterator *it,
"\t\t%u.%u.%u.%-3u\n",
p->key, NIPQUAD(p->dest_net_ip),
NIPQUAD(p->dest_net_mask), NIPQUAD(p->gw_ip));
- else
+ else if (p->dest_net_ip != INADDR_ANY)
xnvfile_printf(it,
"*\t%u.%u.%u.%-3u\t%u.%u.%u.%-3u\t\t"
"%u.%u.%u.%-3u\n",
NIPQUAD(p->dest_net_ip),
NIPQUAD(p->dest_net_mask), NIPQUAD(p->gw_ip));
+ else
+ xnvfile_printf(it,
+ "*\t%-11s\t0.0.0.0\t\t\t%u.%u.%u.%-3u\n",
+ "default", NIPQUAD(p->gw_ip));
return 0;
}
@@ -760,6 +773,17 @@ int rt_ip_route_add_net(u32 addr, u32 mask, u32 gw_addr)
unsigned int key;
u32 shifted_mask;
+ rtdm_lock_get_irqsave(&net_table_lock, context);
+
+ if (addr == INADDR_ANY) {
+ default_gw_ip = gw_addr;
+ allocated_net_routes++;
+ rtdm_lock_put_irqrestore(&net_table_lock, context);
+ return 0;
+ }
+
+ rtdm_lock_put_irqrestore(&net_table_lock, context);
+
addr &= mask;
if ((new_route = rt_alloc_net_route()) != NULL) {
@@ -823,6 +847,17 @@ int rt_ip_route_del_net(u32 addr, u32 mask)
unsigned int key;
u32 shifted_mask;
+ rtdm_lock_get_irqsave(&net_table_lock, context);
+
+ if (addr == INADDR_ANY) {
+ default_gw_ip = INADDR_ANY;
+ allocated_net_routes--;
+ rtdm_lock_put_irqrestore(&net_table_lock, context);
+ return 0;
+ }
+
+ rtdm_lock_put_irqrestore(&net_table_lock, context);
+
addr &= mask;
shifted_mask = NET_HASH_KEY_MASK << net_hash_key_shift;
@@ -856,6 +891,7 @@ int rt_ip_route_del_net(u32 addr, u32 mask)
return -ENOENT;
}
+
#endif /* CONFIG_XENO_DRIVERS_NET_RTIPV4_NETROUTING */
/***
@@ -915,8 +951,9 @@ restart:
else
while (host_rt != NULL) {
if ((host_rt->dest_host.ip == daddr) &&
- (host_rt->dest_host.rtdev->local_ip == saddr))
+ (host_rt->dest_host.rtdev->local_ip == saddr)) {
goto host_route_found;
+ }
host_rt = host_rt->next;
}
@@ -947,7 +984,7 @@ restart:
rtdm_lock_put_irqrestore(&net_table_lock, context);
- /* last try: no hash key */
+ /* no hash key */
rtdm_lock_get_irqsave(&net_table_lock, context);
net_rt = net_hash_tbl[NET_HASH_TBL_SIZE];
@@ -966,6 +1003,13 @@ restart:
net_rt = net_rt->next;
}
+ /* last try: use default route if any. */
+ if (default_gw_ip != INADDR_ANY) {
+ daddr = default_gw_ip;
+ rtdm_lock_put_irqrestore(&net_table_lock, context);
+ goto restart;
+ }
+
rtdm_lock_put_irqrestore(&net_table_lock, context);
}
#endif /* CONFIG_XENO_DRIVERS_NET_RTIPV4_NETROUTING */
--
2.17.1
