X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Fnetdev-linux.c;h=2fa05b66e3e2162f346a0369d1e2c641a3a15c76;hb=1e82e503c5358f8dce9eb2105448f0ec894d57bc;hp=b8d24ed999cad953785f8862d8aa544812221c43;hpb=2158888d8d8f3b4c00dcf979390a19fa7fcf7942;p=openvswitch

diff --git a/lib/netdev-linux.c b/lib/netdev-linux.c
index b8d24ed9..2fa05b66 100644
--- a/lib/netdev-linux.c
+++ b/lib/netdev-linux.c
@@ -88,6 +88,7 @@ enum {
 
 struct tap_state {
     int fd;
+    bool opened;
 };
 
 struct netdev_dev_linux {
@@ -371,8 +372,15 @@ netdev_linux_open(struct netdev_dev *netdev_dev_, int ethertype,
         goto error;
     }
 
-    if (!strcmp(netdev_dev_get_type(netdev_dev_), "tap")) {
+    if (!strcmp(netdev_dev_get_type(netdev_dev_), "tap") &&
+        !netdev_dev->state.tap.opened) {
+
+        /* We assume that the first user of the tap device is the primary user
+         * and give them the tap FD.  Subsequent users probably just expect
+         * this to be a system device so open it normally to avoid send/receive
+         * directions appearing to be reversed. */
         netdev->fd = netdev_dev->state.tap.fd;
+        netdev_dev->state.tap.opened = true;
     } else if (ethertype != NETDEV_ETH_TYPE_NONE) {
         struct sockaddr_ll sll;
         int protocol;
@@ -779,6 +787,14 @@ netdev_linux_update_is_pseudo(struct netdev_dev_linux *netdev_dev)
     }
 }
 
+static void
+swap_uint64(uint64_t *a, uint64_t *b)
+{
+    *a ^= *b;
+    *b ^= *a;
+    *a ^= *b;
+}
+
 /* Retrieves current device stats for 'netdev'.
  *
  * XXX All of the members of struct netdev_stats are 64 bits wide, but on
@@ -791,16 +807,9 @@ netdev_linux_get_stats(const struct netdev *netdev_,
                                 netdev_dev_linux_cast(netdev_get_dev(netdev_));
     static int use_netlink_stats = -1;
     int error;
-    struct netdev_stats raw_stats;
-    struct netdev_stats *collect_stats = stats;
 
     COVERAGE_INC(netdev_get_stats);
 
-    netdev_linux_update_is_pseudo(netdev_dev);
-    if (netdev_dev->is_internal) {
-        collect_stats = &raw_stats;
-    }
-
     if (use_netlink_stats < 0) {
         use_netlink_stats = check_for_working_netlink_stats();
     }
@@ -809,27 +818,22 @@ netdev_linux_get_stats(const struct netdev *netdev_,
 
         error = get_ifindex(netdev_, &ifindex);
         if (!error) {
-            error = get_stats_via_netlink(ifindex, collect_stats);
+            error = get_stats_via_netlink(ifindex, stats);
         }
     } else {
-        error = get_stats_via_proc(netdev_get_name(netdev_), collect_stats);
+        error = get_stats_via_proc(netdev_get_name(netdev_), stats);
     }
 
     /* If this port is an internal port then the transmit and receive stats
      * will appear to be swapped relative to the other ports since we are the
      * one sending the data, not a remote computer.  For consistency, we swap
      * them back here. */
+    netdev_linux_update_is_pseudo(netdev_dev);
     if (!error && (netdev_dev->is_internal || netdev_dev->is_tap)) {
-        stats->rx_packets = raw_stats.tx_packets;
-        stats->tx_packets = raw_stats.rx_packets;
-        stats->rx_bytes = raw_stats.tx_bytes;
-        stats->tx_bytes = raw_stats.rx_bytes;
-        stats->rx_errors = raw_stats.tx_errors;
-        stats->tx_errors = raw_stats.rx_errors;
-        stats->rx_dropped = raw_stats.tx_dropped;
-        stats->tx_dropped = raw_stats.rx_dropped;
-        stats->multicast = raw_stats.multicast;
-        stats->collisions = raw_stats.collisions;
+        swap_uint64(&stats->rx_packets, &stats->tx_packets);
+        swap_uint64(&stats->rx_bytes, &stats->tx_bytes);
+        swap_uint64(&stats->rx_errors, &stats->tx_errors);
+        swap_uint64(&stats->rx_dropped, &stats->tx_dropped);
         stats->rx_length_errors = 0;
         stats->rx_over_errors = 0;
         stats->rx_crc_errors = 0;
@@ -1163,7 +1167,7 @@ netdev_linux_remove_policing(struct netdev *netdev)
     error = nl_sock_transact(rtnl_sock, &request, &reply);
     ofpbuf_uninit(&request);
     ofpbuf_delete(reply);
-    if (error && error != ENOENT) {
+    if (error && error != ENOENT && error != EINVAL) {
         VLOG_WARN_RL(&rl, "%s: removing policing failed: %s",
                      netdev_name, strerror(error));
         return error;