The bridge code needs to keep track of a cost estimate for each
port in the bridge. Instead of a hack based on device name, try
and use ethtool to get port speed from device. This has been tested
on e100 (uses ethtool_ops) and e1000 (does ethtool the hard way)
and dummy (no ethtool).
Need to export dev_ethtool() to allow bridge module to get to
it easily.
Code takes care to maintain same locking and semantics as if ioctl
was being done from application.
diff -Nru a/net/bridge/br_if.c b/net/bridge/br_if.c
--- a/net/bridge/br_if.c Mon Apr 12 16:10:23 2004
+++ b/net/bridge/br_if.c Mon Apr 12 16:10:23 2004
@@ -14,6 +14,8 @@
*/
#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/ethtool.h>
#include <linux/if_arp.h>
#include <linux/module.h>
#include <linux/init.h>
@@ -25,18 +27,55 @@
/* Limited to 256 ports because of STP protocol pdu */
#define BR_MAX_PORTS 256
+/*
+ * Determine initial path cost based on speed.
+ * using recommendations from 802.1d standard
+ *
+ * Need to simulate user ioctl because not all device's that support
+ * ethtool, use ethtool_ops. Also, since driver might sleep need to
+ * not be holding any locks.
+ */
static int br_initial_port_cost(struct net_device *dev)
{
+
+ struct ethtool_cmd ecmd = { ETHTOOL_GSET };
+ struct ifreq ifr;
+ mm_segment_t old_fs;
+ int err;
+
+ strncpy(ifr.ifr_name, dev->name, IFNAMSIZ);
+ ifr.ifr_data = (void *) &ecmd;
+
+ old_fs = get_fs();
+ set_fs(KERNEL_DS);
+ err = dev_ethtool(&ifr);
+ set_fs(old_fs);
+
+ if (!err) {
+ switch(ecmd.speed) {
+ case SPEED_100:
+ return 19;
+ case SPEED_1000:
+ return 4;
+ case SPEED_10000:
+ return 2;
+ case SPEED_10:
+ return 100;
+ default:
+ pr_info("bridge: can't decode speed from %s: %d\n",
+ dev->name, ecmd.speed);
+ return 100;
+ }
+ }
+
+ /* Old silly heuristics based on name */
if (!strncmp(dev->name, "lec", 3))
return 7;
- if (!strncmp(dev->name, "eth", 3))
- return 100; /* FIXME handle 100Mbps */
-
if (!strncmp(dev->name, "plip", 4))
return 2500;
- return 100;
+ return 100; /* assume old 10Mbps */
}
static void destroy_nbp(void *arg)
@@ -147,7 +186,9 @@
}
/* called under bridge lock */
-static struct net_bridge_port *new_nbp(struct net_bridge *br, struct net_device *dev)
+static struct net_bridge_port *new_nbp(struct net_bridge *br,
+ struct net_device *dev,
+ unsigned long cost)
{
int index;
struct net_bridge_port *p;
@@ -162,16 +203,15 @@
memset(p, 0, sizeof(*p));
p->br = br;
+ dev_hold(dev);
p->dev = dev;
- p->path_cost = br_initial_port_cost(dev);
+ p->path_cost = cost;
p->priority = 0x80;
dev->br_port = p;
p->port_no = index;
br_init_port(p);
p->state = BR_STATE_DISABLED;
- list_add_rcu(&p->list, &br->port_list);
-
return p;
}
@@ -216,13 +256,11 @@
return ret;
}
-/* called under bridge lock */
int br_add_if(struct net_bridge *br, struct net_device *dev)
{
struct net_bridge_port *p;
-
- if (dev->br_port != NULL)
- return -EBUSY;
+ unsigned long cost;
+ int err = 0;
if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER)
return -EINVAL;
@@ -230,34 +268,46 @@
if (dev->hard_start_xmit == br_dev_xmit)
return -ELOOP;
- dev_hold(dev);
- p = new_nbp(br, dev);
- if (IS_ERR(p)) {
- dev_put(dev);
- return PTR_ERR(p);
- }
+ cost = br_initial_port_cost(dev);
- dev_set_promiscuity(dev, 1);
+ spin_lock_bh(&br->lock);
+ if (dev->br_port != NULL)
+ err = -EBUSY;
+
+ else if (IS_ERR(p = new_nbp(br, dev, cost)))
+ err = PTR_ERR(p);
- br_stp_recalculate_bridge_id(br);
- br_fdb_insert(br, p, dev->dev_addr, 1);
- if ((br->dev->flags & IFF_UP) && (dev->flags & IFF_UP))
- br_stp_enable_port(p);
+ else {
+ dev_set_promiscuity(dev, 1);
- return 0;
+ list_add_rcu(&p->list, &br->port_list);
+
+ br_stp_recalculate_bridge_id(br);
+ br_fdb_insert(br, p, dev->dev_addr, 1);
+ if ((br->dev->flags & IFF_UP) && (dev->flags & IFF_UP))
+ br_stp_enable_port(p);
+
+ }
+ spin_unlock_bh(&br->lock);
+ return err;
}
-/* called under bridge lock */
int br_del_if(struct net_bridge *br, struct net_device *dev)
{
struct net_bridge_port *p;
+ int err = 0;
- if ((p = dev->br_port) == NULL || p->br != br)
- return -EINVAL;
+ spin_lock_bh(&br->lock);
+ p = dev->br_port;
+ if (!p || p->br != br)
+ err = -EINVAL;
+ else {
+ del_nbp(p);
+ br_stp_recalculate_bridge_id(br);
+ }
+ spin_unlock_bh(&br->lock);
- del_nbp(p);
- br_stp_recalculate_bridge_id(br);
- return 0;
+ return err;
}
int br_get_bridge_ifindices(int *indices, int num)
diff -Nru a/net/bridge/br_ioctl.c b/net/bridge/br_ioctl.c
--- a/net/bridge/br_ioctl.c Mon Apr 12 16:10:23 2004
+++ b/net/bridge/br_ioctl.c Mon Apr 12 16:10:23 2004
@@ -48,12 +48,10 @@
if (dev == NULL)
return -EINVAL;
- spin_lock_bh(&br->lock);
if (cmd == BRCTL_ADD_IF)
ret = br_add_if(br, dev);
else
ret = br_del_if(br, dev);
- spin_unlock_bh(&br->lock);
dev_put(dev);
return ret;
diff -Nru a/net/core/ethtool.c b/net/core/ethtool.c
--- a/net/core/ethtool.c Mon Apr 12 16:10:23 2004
+++ b/net/core/ethtool.c Mon Apr 12 16:10:23 2004
@@ -740,6 +740,7 @@
return -EOPNOTSUPP;
}
+EXPORT_SYMBOL(dev_ethtool);
EXPORT_SYMBOL(ethtool_op_get_link);
EXPORT_SYMBOL(ethtool_op_get_sg);
EXPORT_SYMBOL(ethtool_op_get_tso);
