Merge tag 'net-pull-request' of https://github.com/jasowang/qemu into staging

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* tag 'net-pull-request' of https://github.com/jasowang/qemu:
  tap-linux: Open ipvtap and macvtap
  Revert "hw/net/net_tx_pkt: Fix overrun in update_sctp_checksum()"
  util/iov: Do not assert offset is in iov
  net: move backend cleanup to NIC cleanup
  net: parameterize the removing client from nc list

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 34 insertions, 10 deletions

diff --git a/net/net.c b/net/net.c
index a3996d5..39d6f28 100644
--- a/net/net.c
+++ b/net/net.c
@@ -381,9 +381,12 @@ NetClientState *qemu_get_peer(NetClientState *nc, int queue_index)
     return ncs->peer;
 }
 
-static void qemu_cleanup_net_client(NetClientState *nc)
+static void qemu_cleanup_net_client(NetClientState *nc,
+                                    bool remove_from_net_clients)
 {
-    QTAILQ_REMOVE(&net_clients, nc, next);
+    if (remove_from_net_clients) {
+        QTAILQ_REMOVE(&net_clients, nc, next);
+    }
 
     if (nc->info->cleanup) {
         nc->info->cleanup(nc);
@@ -425,7 +428,13 @@ void qemu_del_net_client(NetClientState *nc)
         object_unparent(OBJECT(nf));
     }
 
-    /* If there is a peer NIC, delete and cleanup client, but do not free. */
+    /*
+     * If there is a peer NIC, transfer ownership to it.  Delete the client
+     * from net_client list but do not cleanup nor free.  This way NIC can
+     * still access to members of the backend.
+     *
+     * The cleanup and free will be done when the NIC is free.
+     */
     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
         NICState *nic = qemu_get_nic(nc->peer);
         if (nic->peer_deleted) {
@@ -435,21 +444,18 @@ void qemu_del_net_client(NetClientState *nc)
 
         for (i = 0; i < queues; i++) {
             ncs[i]->peer->link_down = true;
+            QTAILQ_REMOVE(&net_clients, ncs[i], next);
         }
 
         if (nc->peer->info->link_status_changed) {
             nc->peer->info->link_status_changed(nc->peer);
         }
 
-        for (i = 0; i < queues; i++) {
-            qemu_cleanup_net_client(ncs[i]);
-        }
-
         return;
     }
 
     for (i = 0; i < queues; i++) {
-        qemu_cleanup_net_client(ncs[i]);
+        qemu_cleanup_net_client(ncs[i], true);
         qemu_free_net_client(ncs[i]);
     }
 }
@@ -462,8 +468,12 @@ void qemu_del_nic(NICState *nic)
 
     for (i = 0; i < queues; i++) {
         NetClientState *nc = qemu_get_subqueue(nic, i);
-        /* If this is a peer NIC and peer has already been deleted, free it now. */
+        /*
+         * If this is a peer NIC and peer has already been deleted, clean it up
+         * and free it now.
+         */
         if (nic->peer_deleted) {
+            qemu_cleanup_net_client(nc->peer, false);
             qemu_free_net_client(nc->peer);
         } else if (nc->peer) {
             /* if there are RX packets pending, complete them */
@@ -474,7 +484,7 @@ void qemu_del_nic(NICState *nic)
     for (i = queues - 1; i >= 0; i--) {
         NetClientState *nc = qemu_get_subqueue(nic, i);
 
-        qemu_cleanup_net_client(nc);
+        qemu_cleanup_net_client(nc, true);
         qemu_free_net_client(nc);
     }
 
@@ -1678,6 +1688,9 @@ void net_cleanup(void)
      * of the latest NET_CLIENT_DRIVER_NIC, and operate on *p as we walk
      * the list.
      *
+     * However, the NIC may have peers that trust to be clean beyond this
+     * point.  For example, if they have been removed with device_del.
+     *
      * The 'nc' variable isn't part of the list traversal; it's purely
      * for convenience as too much '(*p)->' has a tendency to make the
      * readers' eyes bleed.
@@ -1685,6 +1698,17 @@ void net_cleanup(void)
     while (*p) {
         nc = *p;
         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
+            NICState *nic = qemu_get_nic(nc);
+
+            if (nic->peer_deleted) {
+                int queues = MAX(nic->conf->peers.queues, 1);
+
+                for (int i = 0; i < queues; i++) {
+                    nc = qemu_get_subqueue(nic, i);
+                    qemu_cleanup_net_client(nc->peer, false);
+                }
+            }
+
             /* Skip NET_CLIENT_DRIVER_NIC entries */
             p = &QTAILQ_NEXT(nc, next);
         } else {