netdev: Really set output values to 0 on failure in netdev_get_features().

[sliver-openvswitch.git] / lib / netdev-linux.c

diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index 50a0d2d..3ccd6be 100644 (file)
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -370,7 +370,7 @@ netdev_linux_recv(struct netdev *netdev_, void *data, size_t size)
 
     if (netdev->tap_fd < 0) {
         /* Device was opened with NETDEV_ETH_TYPE_NONE. */
-        return EAGAIN;
+        return -EAGAIN;
     }
 
     for (;;) {
@@ -382,7 +382,7 @@ netdev_linux_recv(struct netdev *netdev_, void *data, size_t size)
                 VLOG_WARN_RL(&rl, "error receiving Ethernet packet on %s: %s",
                              strerror(errno), netdev_get_name(netdev_));
             }
-            return errno;
+            return -errno;
         }
     }
 }
@@ -492,9 +492,17 @@ netdev_linux_set_etheraddr(struct netdev *netdev_,
                            const uint8_t mac[ETH_ADDR_LEN])
 {
     struct netdev_linux *netdev = netdev_linux_cast(netdev_);
-    int error = set_etheraddr(netdev_get_name(netdev_), ARPHRD_ETHER, mac);
-    if (!error) {
-        memcpy(netdev->cache->etheraddr, mac, ETH_ADDR_LEN);
+    int error;
+
+    if (!(netdev->cache->valid & VALID_ETHERADDR)
+        || !eth_addr_equals(netdev->cache->etheraddr, mac)) {
+        error = set_etheraddr(netdev_get_name(netdev_), ARPHRD_ETHER, mac);
+        if (!error) {
+            netdev->cache->valid |= VALID_ETHERADDR;
+            memcpy(netdev->cache->etheraddr, mac, ETH_ADDR_LEN);
+        }
+    } else {
+        error = 0;
     }
     return error;
 }
@@ -712,8 +720,7 @@ netdev_linux_get_stats(const struct netdev *netdev_, struct netdev_stats *stats)
 /* Stores the features supported by 'netdev' into each of '*current',
  * '*advertised', '*supported', and '*peer' that are non-null.  Each value is a
  * bitmap of "enum ofp_port_features" bits, in host byte order.  Returns 0 if
- * successful, otherwise a positive errno value.  On failure, all of the
- * passed-in values are set to 0. */
+ * successful, otherwise a positive errno value. */
 static int
 netdev_linux_get_features(struct netdev *netdev,
                           uint32_t *current, uint32_t *advertised,