Support MTU greater than 1500 bytes. Handle SIOCSIFMTU in the virtio-…

…net driver rather than delegating to ether_ioctl.
SpirentOrion · Aug 30, 2019 · 6886bc8 · 6886bc8
1 parent 7cbf0db
commit 6886bc8
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Showing 2 changed files with 16 additions and 1 deletion.
diff --git a/core/dhcp.cc b/core/dhcp.cc
@@ -690,7 +690,10 @@ namespace dhcp {
                  dm.get_interface_mtu() != 0 ? dm.get_interface_mtu() : ETHERMTU);
 
             if (dm.get_interface_mtu() != 0) {
-                osv::if_set_mtu(_ifp->if_xname, dm.get_interface_mtu());
+                int error = osv::if_set_mtu(_ifp->if_xname, dm.get_interface_mtu());
+                if (error != 0) {
+                    dhcp_i("Unable to set MTU on %s: %s", _ifp->if_xname, strerror(error));
+                }
             }
             osv::start_if(_ifp->if_xname,
                           dm.get_your_ip().to_string().c_str(),

diff --git a/drivers/virtio-net.cc b/drivers/virtio-net.cc
@@ -30,6 +30,7 @@
 #include <osv/ioctl.h>
 #include <bsd/sys/net/ethernet.h>
 #include <bsd/sys/net/if_types.h>
+#include <bsd/sys/net/if.h>
 #include <bsd/sys/sys/param.h>
 
 #include <bsd/sys/net/ethernet.h>
@@ -94,6 +95,17 @@ static int if_ioctl(struct ifnet* ifp, u_long command, caddr_t data)
     case SIOCDELMULTI:
         net_d("SIOCDELMULTI");
         break;
+    case SIOCSIFMTU:
+        {
+            net_d("SIOCSIFMTU");
+            struct bsd_ifreq *ifr = (struct bsd_ifreq *)data;
+            if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > ETHERMTU_JUMBO) {
+                error = EINVAL;
+            } else {
+                ifp->if_mtu = ifr->ifr_mtu;
+            }
+        }
+        break;
     default:
         net_d("redirecting to ether_ioctl()...");
         error = ether_ioctl(ifp, command, data);