datapath: Make openvswitch_ioctl() have a single point of exit.

[openvswitch] / datapath / datapath.c

diff --git a/datapath/datapath.c b/datapath/datapath.c
index 27bc5ce47e429183056695c11624ebf06b6a3f94..e545cda0518a0aaae3b46bd3f8bc766a79da296c 100644 (file)
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -831,6 +831,7 @@ static void get_stats(struct sw_flow *flow, struct odp_flow_stats *stats)
        stats->n_bytes = flow->byte_count;
        stats->ip_tos = flow->ip_tos;
        stats->tcp_flags = flow->tcp_flags;
+       stats->error = 0;
 }
 
 static void clear_stats(struct sw_flow *flow)
@@ -984,9 +985,7 @@ static int answer_query(struct sw_flow *flow, struct odp_flow __user *ufp)
        return put_actions(flow, ufp);
 }
 
-static int del_or_query_flow(struct datapath *dp,
-                            struct odp_flow __user *ufp,
-                            unsigned int cmd)
+static int del_flow(struct datapath *dp, struct odp_flow __user *ufp)
 {
        struct dp_table *table = rcu_dereference(dp->table);
        struct odp_flow uf;
@@ -1003,29 +1002,24 @@ static int del_or_query_flow(struct datapath *dp,
        if (!flow)
                goto error;
 
-       if (cmd == ODP_FLOW_DEL) {
-               /* XXX redundant lookup */
-               error = dp_table_delete(table, flow);
-               if (error)
-                       goto error;
+       /* XXX redundant lookup */
+       error = dp_table_delete(table, flow);
+       if (error)
+               goto error;
 
-               /* XXX These statistics might lose a few packets, since other
-                * CPUs can be using this flow.  We used to synchronize_rcu()
-                * to make sure that we get completely accurate stats, but that
-                * blows our performance, badly. */
-               dp->n_flows--;
-               error = answer_query(flow, ufp);
-               flow_deferred_free(flow);
-       } else {
-               error = answer_query(flow, ufp);
-       }
+       /* XXX These statistics might lose a few packets, since other CPUs can
+        * be using this flow.  We used to synchronize_rcu() to make sure that
+        * we get completely accurate stats, but that blows our performance,
+        * badly. */
+       dp->n_flows--;
+       error = answer_query(flow, ufp);
+       flow_deferred_free(flow);
 
 error:
        return error;
 }
 
-static int query_multiple_flows(struct datapath *dp,
-                               const struct odp_flowvec *flowvec)
+static int query_flows(struct datapath *dp, const struct odp_flowvec *flowvec)
 {
        struct dp_table *table = rcu_dereference(dp->table);
        int i;
@@ -1041,7 +1035,7 @@ static int query_multiple_flows(struct datapath *dp,
 
                flow = dp_table_lookup(table, &uf.key);
                if (!flow)
-                       error = __clear_user(&ufp->stats, sizeof ufp->stats);
+                       error = __put_user(ENOENT, &ufp->stats.error);
                else
                        error = answer_query(flow, ufp);
                if (error)
@@ -1174,8 +1168,7 @@ error:
        return err;
 }
 
-static int
-get_dp_stats(struct datapath *dp, struct odp_stats __user *statsp)
+static int get_dp_stats(struct datapath *dp, struct odp_stats __user *statsp)
 {
        struct odp_stats stats;
        int i;
@@ -1351,24 +1344,28 @@ static long openvswitch_ioctl(struct file *f, unsigned int cmd,
        /* Handle commands with special locking requirements up front. */
        switch (cmd) {
        case ODP_DP_CREATE:
-               return create_dp(dp_idx, (char __user *)argp);
+               err = create_dp(dp_idx, (char __user *)argp);
+               goto exit;
 
        case ODP_DP_DESTROY:
-               return destroy_dp(dp_idx);
+               err = destroy_dp(dp_idx);
+               goto exit;
 
        case ODP_PORT_ADD:
-               return add_port(dp_idx, (struct odp_port __user *)argp);
+               err = add_port(dp_idx, (struct odp_port __user *)argp);
+               goto exit;
 
        case ODP_PORT_DEL:
                err = get_user(port_no, (int __user *)argp);
-               if (err)
-                       break;
-               return del_port(dp_idx, port_no);
+               if (!err)
+                       err = del_port(dp_idx, port_no);
+               goto exit;
        }
 
        dp = get_dp_locked(dp_idx);
+       err = -ENODEV;
        if (!dp)
-               return -ENODEV;
+               goto exit;
 
        switch (cmd) {
        case ODP_DP_STATS:
@@ -1430,13 +1427,11 @@ static long openvswitch_ioctl(struct file *f, unsigned int cmd,
                break;
 
        case ODP_FLOW_DEL:
-       case ODP_FLOW_GET:
-               err = del_or_query_flow(dp, (struct odp_flow __user *)argp,
-                                       cmd);
+               err = del_flow(dp, (struct odp_flow __user *)argp);
                break;
 
-       case ODP_FLOW_GET_MULTIPLE:
-               err = do_flowvec_ioctl(dp, argp, query_multiple_flows);
+       case ODP_FLOW_GET:
+               err = do_flowvec_ioctl(dp, argp, query_flows);
                break;
 
        case ODP_FLOW_LIST:
@@ -1452,6 +1447,7 @@ static long openvswitch_ioctl(struct file *f, unsigned int cmd,
                break;
        }
        mutex_unlock(&dp->mutex);
+exit:
        return err;
 }