ofp-errors: Add OFPET_FLOW_MONITOR_FAILED
[cascardo/ovs.git] / ofproto / ofproto.c
index 659990e..a05a444 100644 (file)
@@ -58,6 +58,7 @@
 #include "unaligned.h"
 #include "unixctl.h"
 #include "vlog.h"
+#include "bundles.h"
 
 VLOG_DEFINE_THIS_MODULE(ofproto);
 
@@ -68,80 +69,10 @@ COVERAGE_DEFINE(ofproto_recv_openflow);
 COVERAGE_DEFINE(ofproto_reinit_ports);
 COVERAGE_DEFINE(ofproto_update_port);
 
-enum ofproto_state {
-    S_OPENFLOW,                 /* Processing OpenFlow commands. */
-    S_EVICT,                    /* Evicting flows from over-limit tables. */
-    S_FLUSH,                    /* Deleting all flow table rules. */
-};
-
-enum ofoperation_type {
-    OFOPERATION_ADD,
-    OFOPERATION_DELETE,
-    OFOPERATION_MODIFY,
-    OFOPERATION_REPLACE
-};
-
-/* A single OpenFlow request can execute any number of operations.  The
- * ofopgroup maintain OpenFlow state common to all of the operations, e.g. the
- * ofconn to which an error reply should be sent if necessary.
- *
- * ofproto initiates some operations internally.  These operations are still
- * assigned to groups but will not have an associated ofconn. */
-struct ofopgroup {
-    struct ofproto *ofproto;    /* Owning ofproto. */
-    struct list ofproto_node;   /* In ofproto's "pending" list. */
-    struct list ops;            /* List of "struct ofoperation"s. */
-    int n_running;              /* Number of ops still pending. */
-
-    /* Data needed to send OpenFlow reply on failure or to send a buffered
-     * packet on success.
-     *
-     * If list_is_empty(ofconn_node) then this ofopgroup never had an
-     * associated ofconn or its ofconn's connection dropped after it initiated
-     * the operation.  In the latter case 'ofconn' is a wild pointer that
-     * refers to freed memory, so the 'ofconn' member must be used only if
-     * !list_is_empty(ofconn_node).
-     */
-    struct list ofconn_node;    /* In ofconn's list of pending opgroups. */
-    struct ofconn *ofconn;      /* ofconn for reply (but see note above). */
-    struct ofp_header *request; /* Original request (truncated at 64 bytes). */
-    uint32_t buffer_id;         /* Buffer id from original request. */
-};
-
-static struct ofopgroup *ofopgroup_create_unattached(struct ofproto *);
-static struct ofopgroup *ofopgroup_create(struct ofproto *, struct ofconn *,
-                                          const struct ofp_header *,
-                                          uint32_t buffer_id);
-static void ofopgroup_submit(struct ofopgroup *);
-static void ofopgroup_complete(struct ofopgroup *);
-
-/* A single flow table operation. */
-struct ofoperation {
-    struct ofopgroup *group;    /* Owning group. */
-    struct list group_node;     /* In ofopgroup's "ops" list. */
-    struct hmap_node hmap_node; /* In ofproto's "deletions" hmap. */
-    struct rule *rule;          /* Rule being operated upon. */
-    enum ofoperation_type type; /* Type of operation. */
-
-    /* OFOPERATION_MODIFY, OFOPERATION_REPLACE: The old actions, if the actions
-     * are changing. */
-    struct rule_actions *actions;
-
-    /* OFOPERATION_DELETE. */
-    enum ofp_flow_removed_reason reason; /* Reason flow was removed. */
-
-    ovs_be64 flow_cookie;               /* Rule's old flow cookie. */
-    uint16_t idle_timeout;              /* Rule's old idle timeout. */
-    uint16_t hard_timeout;              /* Rule's old hard timeout. */
-    enum ofputil_flow_mod_flags flags;  /* Rule's old flags. */
-    enum ofperr error;                  /* 0 if no error. */
-};
-
-static struct ofoperation *ofoperation_create(struct ofopgroup *,
-                                              struct rule *,
-                                              enum ofoperation_type,
-                                              enum ofp_flow_removed_reason);
-static void ofoperation_destroy(struct ofoperation *);
+/* Default fields to use for prefix tries in each flow table, unless something
+ * else is configured. */
+const enum mf_field_id default_prefix_fields[2] =
+    { MFF_IPV4_DST, MFF_IPV4_SRC };
 
 /* oftable. */
 static void oftable_init(struct oftable *);
@@ -149,6 +80,9 @@ static void oftable_destroy(struct oftable *);
 
 static void oftable_set_name(struct oftable *, const char *name);
 
+static enum ofperr evict_rules_from_table(struct oftable *,
+                                          unsigned int extra_space)
+    OVS_REQUIRES(ofproto_mutex);
 static void oftable_disable_eviction(struct oftable *);
 static void oftable_enable_eviction(struct oftable *,
                                     const struct mf_subfield *fields,
@@ -157,7 +91,6 @@ static void oftable_enable_eviction(struct oftable *,
 static void oftable_remove_rule(struct rule *rule) OVS_REQUIRES(ofproto_mutex);
 static void oftable_remove_rule__(struct ofproto *, struct rule *)
     OVS_REQUIRES(ofproto_mutex);
-static void oftable_insert_rule(struct rule *);
 
 /* A set of rules within a single OpenFlow table (oftable) that have the same
  * values for the oftable's eviction_fields.  A rule to be evicted, when one is
@@ -181,11 +114,14 @@ struct eviction_group {
     struct heap rules;          /* Contains "struct rule"s. */
 };
 
-static bool choose_rule_to_evict(struct oftable *table, struct rule **rulep);
-static void ofproto_evict(struct ofproto *) OVS_EXCLUDED(ofproto_mutex);
-static uint32_t rule_eviction_priority(struct ofproto *ofproto, struct rule *);
-static void eviction_group_add_rule(struct rule *);
-static void eviction_group_remove_rule(struct rule *);
+static bool choose_rule_to_evict(struct oftable *table, struct rule **rulep)
+    OVS_REQUIRES(ofproto_mutex);
+static uint32_t rule_eviction_priority(struct ofproto *ofproto, struct rule *)
+    OVS_REQUIRES(ofproto_mutex);;
+static void eviction_group_add_rule(struct rule *)
+    OVS_REQUIRES(ofproto_mutex);
+static void eviction_group_remove_rule(struct rule *)
+    OVS_REQUIRES(ofproto_mutex);
 
 /* Criteria that flow_mod and other operations use for selecting rules on
  * which to operate. */
@@ -210,6 +146,10 @@ struct rule_criteria {
      * If out_group != OFPG_ALL, select only rules that output to out_group. */
     ofp_port_t out_port;
     uint32_t out_group;
+
+    /* If true, collects only rules that are modifiable. */
+    bool include_hidden;
+    bool include_readonly;
 };
 
 static void rule_criteria_init(struct rule_criteria *, uint8_t table_id,
@@ -217,8 +157,14 @@ static void rule_criteria_init(struct rule_criteria *, uint8_t table_id,
                                unsigned int priority,
                                ovs_be64 cookie, ovs_be64 cookie_mask,
                                ofp_port_t out_port, uint32_t out_group);
+static void rule_criteria_require_rw(struct rule_criteria *,
+                                     bool can_write_readonly);
 static void rule_criteria_destroy(struct rule_criteria *);
 
+static enum ofperr collect_rules_loose(struct ofproto *,
+                                       const struct rule_criteria *,
+                                       struct rule_collection *);
+
 /* A packet that needs to be passed to rule_execute().
  *
  * (We can't do this immediately from ofopgroup_complete() because that holds
@@ -233,6 +179,37 @@ struct rule_execute {
 static void run_rule_executes(struct ofproto *) OVS_EXCLUDED(ofproto_mutex);
 static void destroy_rule_executes(struct ofproto *);
 
+struct learned_cookie {
+    union {
+        /* In struct ofproto's 'learned_cookies' hmap. */
+        struct hmap_node hmap_node OVS_GUARDED_BY(ofproto_mutex);
+
+        /* In 'dead_cookies' list when removed from hmap. */
+        struct list list_node;
+    } u;
+
+    /* Key. */
+    ovs_be64 cookie OVS_GUARDED_BY(ofproto_mutex);
+    uint8_t table_id OVS_GUARDED_BY(ofproto_mutex);
+
+    /* Number of references from "learn" actions.
+     *
+     * When this drops to 0, all of the flows in 'table_id' with the specified
+     * 'cookie' are deleted. */
+    int n OVS_GUARDED_BY(ofproto_mutex);
+};
+
+static const struct ofpact_learn *next_learn_with_delete(
+    const struct rule_actions *, const struct ofpact_learn *start);
+
+static void learned_cookies_inc(struct ofproto *, const struct rule_actions *)
+    OVS_REQUIRES(ofproto_mutex);
+static void learned_cookies_dec(struct ofproto *, const struct rule_actions *,
+                                struct list *dead_cookies)
+    OVS_REQUIRES(ofproto_mutex);
+static void learned_cookies_flush(struct ofproto *, struct list *dead_cookies)
+    OVS_REQUIRES(ofproto_mutex);
+
 /* ofport. */
 static void ofport_destroy__(struct ofport *) OVS_EXCLUDED(ofproto_mutex);
 static void ofport_destroy(struct ofport *);
@@ -260,23 +237,35 @@ struct ofport_usage {
 
 /* rule. */
 static void ofproto_rule_send_removed(struct rule *, uint8_t reason);
-static bool rule_is_modifiable(const struct rule *rule,
-                               enum ofputil_flow_mod_flags flag);
+static bool rule_is_readonly(const struct rule *);
+
+/* The source of a flow_mod request, in the code that processes flow_mods.
+ *
+ * A flow table modification request can be generated externally, via OpenFlow,
+ * or internally through a function call.  This structure indicates the source
+ * of an OpenFlow-generated flow_mod.  For an internal flow_mod, it isn't
+ * meaningful and thus supplied as NULL. */
+struct flow_mod_requester {
+    struct ofconn *ofconn;      /* Connection on which flow_mod arrived. */
+    ovs_be32 xid;               /* OpenFlow xid of flow_mod request. */
+};
 
 /* OpenFlow. */
-static enum ofperr add_flow(struct ofproto *, struct ofconn *,
-                            struct ofputil_flow_mod *,
-                            const struct ofp_header *);
-static void do_add_flow(struct ofproto *, struct ofconn *,
-                        const struct ofp_header *request, uint32_t buffer_id,
-                        struct rule *);
-static enum ofperr modify_flows__(struct ofproto *, struct ofconn *,
-                                  struct ofputil_flow_mod *,
-                                  const struct ofp_header *,
-                                  const struct rule_collection *);
-static void delete_flow__(struct rule *rule, struct ofopgroup *,
-                          enum ofp_flow_removed_reason)
+static enum ofperr add_flow(struct ofproto *, struct ofputil_flow_mod *,
+                            const struct flow_mod_requester *);
+
+static enum ofperr modify_flows__(struct ofproto *, struct ofputil_flow_mod *,
+                                  const struct rule_collection *,
+                                  const struct flow_mod_requester *);
+static void delete_flows__(const struct rule_collection *,
+                           enum ofp_flow_removed_reason,
+                           const struct flow_mod_requester *)
+    OVS_REQUIRES(ofproto_mutex);
+
+static enum ofperr send_buffered_packet(struct ofconn *, uint32_t buffer_id,
+                                        struct rule *)
     OVS_REQUIRES(ofproto_mutex);
+
 static bool ofproto_group_exists__(const struct ofproto *ofproto,
                                    uint32_t group_id)
     OVS_REQ_RDLOCK(ofproto->groups_rwlock);
@@ -284,10 +273,10 @@ static bool ofproto_group_exists(const struct ofproto *ofproto,
                                  uint32_t group_id)
     OVS_EXCLUDED(ofproto->groups_rwlock);
 static enum ofperr add_group(struct ofproto *, struct ofputil_group_mod *);
-static bool handle_openflow(struct ofconn *, const struct ofpbuf *);
-static enum ofperr handle_flow_mod__(struct ofproto *, struct ofconn *,
+static void handle_openflow(struct ofconn *, const struct ofpbuf *);
+static enum ofperr handle_flow_mod__(struct ofproto *,
                                      struct ofputil_flow_mod *,
-                                     const struct ofp_header *)
+                                     const struct flow_mod_requester *)
     OVS_EXCLUDED(ofproto_mutex);
 static void calc_duration(long long int start, long long int now,
                           uint32_t *sec, uint32_t *nsec);
@@ -298,6 +287,7 @@ static uint64_t pick_fallback_dpid(void);
 static void ofproto_destroy__(struct ofproto *);
 static void update_mtu(struct ofproto *, struct ofport *);
 static void meter_delete(struct ofproto *, uint32_t first, uint32_t last);
+static void meter_insert_rule(struct rule *);
 
 /* unixctl. */
 static void ofproto_unixctl_init(void);
@@ -522,17 +512,10 @@ ofproto_create(const char *datapath_name, const char *datapath_type,
     ofproto->tables = NULL;
     ofproto->n_tables = 0;
     hindex_init(&ofproto->cookies);
+    hmap_init(&ofproto->learned_cookies);
     list_init(&ofproto->expirable);
     ofproto->connmgr = connmgr_create(ofproto, datapath_name, datapath_name);
-    ofproto->state = S_OPENFLOW;
-    list_init(&ofproto->pending);
-    ofproto->n_pending = 0;
-    hmap_init(&ofproto->deletions);
     guarded_list_init(&ofproto->rule_executes);
-    ofproto->n_add = ofproto->n_delete = ofproto->n_modify = 0;
-    ofproto->first_op = ofproto->last_op = LLONG_MIN;
-    ofproto->next_op_report = LLONG_MAX;
-    ofproto->op_backoff = LLONG_MIN;
     ofproto->vlan_bitmap = NULL;
     ofproto->vlans_changed = false;
     ofproto->min_mtu = INT_MAX;
@@ -1194,26 +1177,13 @@ ofproto_configure_table(struct ofproto *ofproto, int table_id,
 
     table->max_flows = s->max_flows;
     fat_rwlock_wrlock(&table->cls.rwlock);
-    if (classifier_count(&table->cls) > table->max_flows
-        && table->eviction_fields) {
-        /* 'table' contains more flows than allowed.  We might not be able to
-         * evict them right away because of the asynchronous nature of flow
-         * table changes.  Schedule eviction for later. */
-        switch (ofproto->state) {
-        case S_OPENFLOW:
-            ofproto->state = S_EVICT;
-            break;
-        case S_EVICT:
-        case S_FLUSH:
-            /* We're already deleting flows, nothing more to do. */
-            break;
-        }
-    }
-
     classifier_set_prefix_fields(&table->cls,
                                  s->prefix_fields, s->n_prefix_fields);
-
     fat_rwlock_unlock(&table->cls.rwlock);
+
+    ovs_mutex_lock(&ofproto_mutex);
+    evict_rules_from_table(table, 0);
+    ovs_mutex_unlock(&ofproto_mutex);
 }
 \f
 bool
@@ -1229,17 +1199,15 @@ ofproto_get_snoops(const struct ofproto *ofproto, struct sset *snoops)
 }
 
 static void
-ofproto_rule_delete__(struct ofproto *ofproto, struct rule *rule,
-                      uint8_t reason)
+ofproto_rule_delete__(struct rule *rule, uint8_t reason)
     OVS_REQUIRES(ofproto_mutex)
 {
-    struct ofopgroup *group;
-
-    ovs_assert(!rule->pending);
+    struct rule_collection rules;
 
-    group = ofopgroup_create_unattached(ofproto);
-    delete_flow__(rule, group, reason);
-    ofopgroup_submit(group);
+    rules.rules = rules.stub;
+    rules.n = 1;
+    rules.stub[0] = rule;
+    delete_flows__(&rules, reason, NULL);
 }
 
 /* Deletes 'rule' from 'ofproto'.
@@ -1255,17 +1223,12 @@ void
 ofproto_rule_delete(struct ofproto *ofproto, struct rule *rule)
     OVS_EXCLUDED(ofproto_mutex)
 {
-    struct ofopgroup *group;
-
+    /* This skips the ofmonitor and flow-removed notifications because the
+     * switch is being deleted and any OpenFlow channels have been or soon will
+     * be killed. */
     ovs_mutex_lock(&ofproto_mutex);
-    ovs_assert(!rule->pending);
-
-    group = ofopgroup_create_unattached(ofproto);
-    ofoperation_create(group, rule, OFOPERATION_DELETE, OFPRR_DELETE);
     oftable_remove_rule__(ofproto, rule);
     ofproto->ofproto_class->rule_delete(rule);
-    ofopgroup_submit(group);
-
     ovs_mutex_unlock(&ofproto_mutex);
 }
 
@@ -1292,9 +1255,7 @@ ofproto_flush__(struct ofproto *ofproto)
         cls_cursor_init(&cursor, &table->cls, NULL);
         fat_rwlock_unlock(&table->cls.rwlock);
         CLS_CURSOR_FOR_EACH_SAFE (rule, next_rule, cr, &cursor) {
-            if (!rule->pending) {
-                ofproto_rule_delete__(ofproto, rule, OFPRR_DELETE);
-            }
+            ofproto_rule_delete__(rule, OFPRR_DELETE);
         }
     }
     ovs_mutex_unlock(&ofproto_mutex);
@@ -1308,12 +1269,10 @@ ofproto_destroy__(struct ofproto *ofproto)
 {
     struct oftable *table;
 
-    ovs_assert(list_is_empty(&ofproto->pending));
-
     destroy_rule_executes(ofproto);
-    guarded_list_destroy(&ofproto->rule_executes);
-
     delete_group(ofproto, OFPG_ALL);
+
+    guarded_list_destroy(&ofproto->rule_executes);
     ovs_rwlock_destroy(&ofproto->groups_rwlock);
     hmap_destroy(&ofproto->groups);
 
@@ -1337,7 +1296,11 @@ ofproto_destroy__(struct ofproto *ofproto)
     }
     free(ofproto->tables);
 
-    hmap_destroy(&ofproto->deletions);
+    ovs_assert(hindex_is_empty(&ofproto->cookies));
+    hindex_destroy(&ofproto->cookies);
+
+    ovs_assert(hmap_is_empty(&ofproto->learned_cookies));
+    hmap_destroy(&ofproto->learned_cookies);
 
     free(ofproto->vlan_bitmap);
 
@@ -1433,19 +1396,6 @@ ofproto_type_wait(const char *datapath_type)
     }
 }
 
-static bool
-any_pending_ops(const struct ofproto *p)
-    OVS_EXCLUDED(ofproto_mutex)
-{
-    bool b;
-
-    ovs_mutex_lock(&ofproto_mutex);
-    b = !list_is_empty(&p->pending);
-    ovs_mutex_unlock(&ofproto_mutex);
-
-    return b;
-}
-
 int
 ofproto_run(struct ofproto *p)
 {
@@ -1535,68 +1485,7 @@ ofproto_run(struct ofproto *p)
         p->change_seq = new_seq;
     }
 
-    switch (p->state) {
-    case S_OPENFLOW:
-        connmgr_run(p->connmgr, handle_openflow);
-        break;
-
-    case S_EVICT:
-        connmgr_run(p->connmgr, NULL);
-        ofproto_evict(p);
-        if (!any_pending_ops(p)) {
-            p->state = S_OPENFLOW;
-        }
-        break;
-
-    case S_FLUSH:
-        connmgr_run(p->connmgr, NULL);
-        ofproto_flush__(p);
-        if (!any_pending_ops(p)) {
-            connmgr_flushed(p->connmgr);
-            p->state = S_OPENFLOW;
-        }
-        break;
-
-    default:
-        OVS_NOT_REACHED();
-    }
-
-    if (time_msec() >= p->next_op_report) {
-        long long int ago = (time_msec() - p->first_op) / 1000;
-        long long int interval = (p->last_op - p->first_op) / 1000;
-        struct ds s;
-
-        ds_init(&s);
-        ds_put_format(&s, "%d flow_mods ",
-                      p->n_add + p->n_delete + p->n_modify);
-        if (interval == ago) {
-            ds_put_format(&s, "in the last %lld s", ago);
-        } else if (interval) {
-            ds_put_format(&s, "in the %lld s starting %lld s ago",
-                          interval, ago);
-        } else {
-            ds_put_format(&s, "%lld s ago", ago);
-        }
-
-        ds_put_cstr(&s, " (");
-        if (p->n_add) {
-            ds_put_format(&s, "%d adds, ", p->n_add);
-        }
-        if (p->n_delete) {
-            ds_put_format(&s, "%d deletes, ", p->n_delete);
-        }
-        if (p->n_modify) {
-            ds_put_format(&s, "%d modifications, ", p->n_modify);
-        }
-        s.length -= 2;
-        ds_put_char(&s, ')');
-
-        VLOG_INFO("%s: %s", p->name, ds_cstr(&s));
-        ds_destroy(&s);
-
-        p->n_add = p->n_delete = p->n_modify = 0;
-        p->next_op_report = LLONG_MAX;
-    }
+    connmgr_run(p->connmgr, handle_openflow);
 
     return error;
 }
@@ -1609,20 +1498,7 @@ ofproto_wait(struct ofproto *p)
         p->ofproto_class->port_poll_wait(p);
     }
     seq_wait(connectivity_seq_get(), p->change_seq);
-
-    switch (p->state) {
-    case S_OPENFLOW:
-        connmgr_wait(p->connmgr, true);
-        break;
-
-    case S_EVICT:
-    case S_FLUSH:
-        connmgr_wait(p->connmgr, false);
-        if (!any_pending_ops(p)) {
-            poll_immediate_wake();
-        }
-        break;
-    }
+    connmgr_wait(p->connmgr);
 }
 
 bool
@@ -1641,11 +1517,6 @@ ofproto_get_memory_usage(const struct ofproto *ofproto, struct simap *usage)
 
     simap_increase(usage, "ports", hmap_count(&ofproto->ports));
 
-    ovs_mutex_lock(&ofproto_mutex);
-    simap_increase(usage, "ops",
-                   ofproto->n_pending + hmap_count(&ofproto->deletions));
-    ovs_mutex_unlock(&ofproto_mutex);
-
     n_rules = 0;
     OFPROTO_FOR_EACH_TABLE (table, ofproto) {
         fat_rwlock_rdlock(&table->cls.rwlock);
@@ -1900,6 +1771,7 @@ flow_mod_init(struct ofputil_flow_mod *fm,
     fm->flags = 0;
     fm->ofpacts = CONST_CAST(struct ofpact *, ofpacts);
     fm->ofpacts_len = ofpacts_len;
+    fm->delete_reason = OFPRR_DELETE;
 }
 
 static int
@@ -1912,7 +1784,7 @@ simple_flow_mod(struct ofproto *ofproto,
 
     flow_mod_init(&fm, match, priority, ofpacts, ofpacts_len, command);
 
-    return handle_flow_mod__(ofproto, NULL, &fm, NULL);
+    return handle_flow_mod__(ofproto, &fm, NULL);
 }
 
 /* Adds a flow to OpenFlow flow table 0 in 'p' that matches 'cls_rule' and
@@ -1941,7 +1813,7 @@ ofproto_add_flow(struct ofproto *ofproto, const struct match *match,
     rule = rule_from_cls_rule(classifier_find_match_exactly(
                                   &ofproto->tables[0].cls, match, priority));
     if (rule) {
-        struct rule_actions *actions = rule_get_actions(rule);
+        const struct rule_actions *actions = rule_get_actions(rule);
         must_add = !ofpacts_equal(actions->ofpacts, actions->ofpacts_len,
                                   ofpacts, ofpacts_len);
     } else {
@@ -1975,14 +1847,13 @@ ofproto_flow_mod(struct ofproto *ofproto, struct ofputil_flow_mod *fm)
     if (fm->command == OFPFC_MODIFY_STRICT && fm->table_id != OFPTT_ALL
         && !(fm->flags & OFPUTIL_FF_RESET_COUNTS)) {
         struct oftable *table = &ofproto->tables[fm->table_id];
-        struct cls_rule match_rule;
         struct rule *rule;
         bool done = false;
 
-        cls_rule_init(&match_rule, &fm->match, fm->priority);
         fat_rwlock_rdlock(&table->cls.rwlock);
-        rule = rule_from_cls_rule(classifier_find_rule_exactly(&table->cls,
-                                                               &match_rule));
+        rule = rule_from_cls_rule(classifier_find_match_exactly(&table->cls,
+                                                                &fm->match,
+                                                                fm->priority));
         if (rule) {
             /* Reading many of the rule fields and writing on 'modified'
              * requires the rule->mutex.  Also, rule->actions may change
@@ -2011,55 +1882,14 @@ ofproto_flow_mod(struct ofproto *ofproto, struct ofputil_flow_mod *fm)
         }
     }
 
-    return handle_flow_mod__(ofproto, NULL, fm, NULL);
-}
-
-/* Resets the modified time for 'rule' or an equivalent rule. If 'rule' is not
- * in the classifier, but an equivalent rule is, unref 'rule' and ref the new
- * rule. Otherwise if 'rule' is no longer installed in the classifier,
- * reinstall it.
- *
- * Returns the rule whose modified time has been reset. */
-struct rule *
-ofproto_refresh_rule(struct rule *rule)
-{
-    const struct oftable *table = &rule->ofproto->tables[rule->table_id];
-    const struct cls_rule *cr = &rule->cr;
-    struct rule *r;
-
-    /* do_add_flow() requires that the rule is not installed. We lock the
-     * ofproto_mutex here so that another thread cannot add the flow before
-     * we get a chance to add it.*/
-    ovs_mutex_lock(&ofproto_mutex);
-
-    fat_rwlock_rdlock(&table->cls.rwlock);
-    r = rule_from_cls_rule(classifier_find_rule_exactly(&table->cls, cr));
-    if (r != rule) {
-        ofproto_rule_ref(r);
-    }
-    fat_rwlock_unlock(&table->cls.rwlock);
-
-    if (!r) {
-        do_add_flow(rule->ofproto, NULL, NULL, 0, rule);
-    } else if  (r != rule) {
-        ofproto_rule_unref(rule);
-        rule = r;
-    }
-    ovs_mutex_unlock(&ofproto_mutex);
-
-    /* Refresh the modified time for the rule. */
-    ovs_mutex_lock(&rule->mutex);
-    rule->modified = MAX(rule->modified, time_msec());
-    ovs_mutex_unlock(&rule->mutex);
-
-    return rule;
+    return handle_flow_mod__(ofproto, fm, NULL);
 }
 
 /* Searches for a rule with matching criteria exactly equal to 'target' in
  * ofproto's table 0 and, if it finds one, deletes it.
  *
  * This is a helper function for in-band control and fail-open. */
-bool
+void
 ofproto_delete_flow(struct ofproto *ofproto,
                     const struct match *target, unsigned int priority)
     OVS_EXCLUDED(ofproto_mutex)
@@ -2074,24 +1904,23 @@ ofproto_delete_flow(struct ofproto *ofproto,
                                                             priority));
     fat_rwlock_unlock(&cls->rwlock);
     if (!rule) {
-        return true;
+        return;
     }
 
-    /* Fall back to a executing a full flow mod.  We can't optimize this at all
-     * because we didn't take enough locks above to ensure that the flow table
-     * didn't already change beneath us.  */
-    return simple_flow_mod(ofproto, target, priority, NULL, 0,
-                           OFPFC_DELETE_STRICT) != OFPROTO_POSTPONE;
+    /* Execute a flow mod.  We can't optimize this at all because we didn't
+     * take enough locks above to ensure that the flow table didn't already
+     * change beneath us. */
+    simple_flow_mod(ofproto, target, priority, NULL, 0, OFPFC_DELETE_STRICT);
 }
 
-/* Starts the process of deleting all of the flows from all of ofproto's flow
- * tables and then reintroducing the flows required by in-band control and
- * fail-open.  The process will complete in a later call to ofproto_run(). */
+/* Delete all of the flows from all of ofproto's flow tables, then reintroduce
+ * the flows required by in-band control and fail-open.  */
 void
 ofproto_flush_flows(struct ofproto *ofproto)
 {
     COVERAGE_INC(ofproto_flush);
-    ofproto->state = S_FLUSH;
+    ofproto_flush__(ofproto);
+    connmgr_flushed(ofproto->connmgr);
 }
 \f
 static void
@@ -2183,7 +2012,7 @@ dealloc_ofp_port(struct ofproto *ofproto, ofp_port_t ofp_port)
 
 /* Opens and returns a netdev for 'ofproto_port' in 'ofproto', or a null
  * pointer if the netdev cannot be opened.  On success, also fills in
- * 'opp'.  */
+ * '*pp'.  */
 static struct netdev *
 ofport_open(struct ofproto *ofproto,
             struct ofproto_port *ofproto_port,
@@ -2226,7 +2055,7 @@ ofport_open(struct ofproto *ofproto,
 }
 
 /* Returns true if most fields of 'a' and 'b' are equal.  Differences in name,
- * port number, and 'config' bits other than OFPUTIL_PS_LINK_DOWN are
+ * port number, and 'config' bits other than OFPUTIL_PC_PORT_DOWN are
  * disregarded. */
 static bool
 ofport_equal(const struct ofputil_phy_port *a,
@@ -2683,41 +2512,51 @@ ofproto_rule_unref(struct rule *rule)
     }
 }
 
+void
+ofproto_group_ref(struct ofgroup *group)
+{
+    if (group) {
+        ovs_refcount_ref(&group->ref_count);
+    }
+}
+
+void
+ofproto_group_unref(struct ofgroup *group)
+{
+    if (group && ovs_refcount_unref(&group->ref_count) == 1) {
+        group->ofproto->ofproto_class->group_destruct(group);
+        ofputil_bucket_list_destroy(&group->buckets);
+        group->ofproto->ofproto_class->group_dealloc(group);
+    }
+}
+
 static uint32_t get_provider_meter_id(const struct ofproto *,
                                       uint32_t of_meter_id);
 
-/* Creates and returns a new 'struct rule_actions', with a ref_count of 1,
- * whose actions are a copy of from the 'ofpacts_len' bytes of 'ofpacts'. */
-struct rule_actions *
-rule_actions_create(const struct ofproto *ofproto,
-                    const struct ofpact *ofpacts, size_t ofpacts_len)
+/* Creates and returns a new 'struct rule_actions', whose actions are a copy
+ * of from the 'ofpacts_len' bytes of 'ofpacts'. */
+const struct rule_actions *
+rule_actions_create(const struct ofpact *ofpacts, size_t ofpacts_len)
 {
     struct rule_actions *actions;
 
-    actions = xmalloc(sizeof *actions);
-    actions->ofpacts = xmemdup(ofpacts, ofpacts_len);
+    actions = xmalloc(sizeof *actions + ofpacts_len);
     actions->ofpacts_len = ofpacts_len;
-    actions->provider_meter_id
-        = get_provider_meter_id(ofproto,
-                                ofpacts_get_meter(ofpacts, ofpacts_len));
+    actions->has_meter = ofpacts_get_meter(ofpacts, ofpacts_len) != 0;
+    memcpy(actions->ofpacts, ofpacts, ofpacts_len);
 
-    return actions;
-}
+    actions->has_learn_with_delete = (next_learn_with_delete(actions, NULL)
+                                      != NULL);
 
-static void
-rule_actions_destroy_cb(struct rule_actions *actions)
-{
-    free(actions->ofpacts);
-    free(actions);
+    return actions;
 }
 
-/* Decrements 'actions''s ref_count and frees 'actions' if the ref_count
- * reaches 0. */
+/* Free the actions after the RCU quiescent period is reached. */
 void
-rule_actions_destroy(struct rule_actions *actions)
+rule_actions_destroy(const struct rule_actions *actions)
 {
     if (actions) {
-        ovsrcu_postpone(rule_actions_destroy_cb, actions);
+        ovsrcu_postpone(free, CONST_CAST(struct rule_actions *, actions));
     }
 }
 
@@ -2750,30 +2589,6 @@ ofproto_rule_has_out_group(const struct rule *rule, uint32_t group_id)
     }
 }
 
-/* Returns true if a rule related to 'op' has an OpenFlow OFPAT_OUTPUT or
- * OFPAT_ENQUEUE action that outputs to 'out_port'. */
-bool
-ofoperation_has_out_port(const struct ofoperation *op, ofp_port_t out_port)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    if (ofproto_rule_has_out_port(op->rule, out_port)) {
-        return true;
-    }
-
-    switch (op->type) {
-    case OFOPERATION_ADD:
-    case OFOPERATION_DELETE:
-        return false;
-
-    case OFOPERATION_MODIFY:
-    case OFOPERATION_REPLACE:
-        return ofpacts_output_to_port(op->actions->ofpacts,
-                                      op->actions->ofpacts_len, out_port);
-    }
-
-    OVS_NOT_REACHED();
-}
-
 static void
 rule_execute_destroy(struct rule_execute *e)
 {
@@ -2818,35 +2633,127 @@ destroy_rule_executes(struct ofproto *ofproto)
     }
 }
 
-/* Returns true if 'rule' should be hidden from the controller.
- *
- * Rules with priority higher than UINT16_MAX are set up by ofproto itself
- * (e.g. by in-band control) and are intentionally hidden from the
- * controller. */
 static bool
-ofproto_rule_is_hidden(const struct rule *rule)
+rule_is_readonly(const struct rule *rule)
+{
+    const struct oftable *table = &rule->ofproto->tables[rule->table_id];
+    return (table->flags & OFTABLE_READONLY) != 0;
+}
+\f
+static uint32_t
+hash_learned_cookie(ovs_be64 cookie_, uint8_t table_id)
 {
-    return (rule->cr.priority > UINT16_MAX);
+    uint64_t cookie = (OVS_FORCE uint64_t) cookie_;
+    return hash_3words(cookie, cookie >> 32, table_id);
 }
 
-static bool
-oftable_is_modifiable(const struct oftable *table,
-                      enum ofputil_flow_mod_flags flags)
+static void
+learned_cookies_update_one__(struct ofproto *ofproto,
+                             const struct ofpact_learn *learn,
+                             int delta, struct list *dead_cookies)
+    OVS_REQUIRES(ofproto_mutex)
 {
-    if (flags & OFPUTIL_FF_NO_READONLY) {
-        return true;
+    uint32_t hash = hash_learned_cookie(learn->cookie, learn->table_id);
+    struct learned_cookie *c;
+
+    HMAP_FOR_EACH_WITH_HASH (c, u.hmap_node, hash, &ofproto->learned_cookies) {
+        if (c->cookie == learn->cookie && c->table_id == learn->table_id) {
+            c->n += delta;
+            ovs_assert(c->n >= 0);
+
+            if (!c->n) {
+                hmap_remove(&ofproto->learned_cookies, &c->u.hmap_node);
+                list_push_back(dead_cookies, &c->u.list_node);
+            }
+
+            return;
+        }
     }
 
-    return !(table->flags & OFTABLE_READONLY);
+    ovs_assert(delta > 0);
+    c = xmalloc(sizeof *c);
+    hmap_insert(&ofproto->learned_cookies, &c->u.hmap_node, hash);
+    c->cookie = learn->cookie;
+    c->table_id = learn->table_id;
+    c->n = delta;
 }
 
-static bool
-rule_is_modifiable(const struct rule *rule, enum ofputil_flow_mod_flags flags)
+static const struct ofpact_learn *
+next_learn_with_delete(const struct rule_actions *actions,
+                       const struct ofpact_learn *start)
+{
+    const struct ofpact *pos;
+
+    for (pos = start ? ofpact_next(&start->ofpact) : actions->ofpacts;
+         pos < ofpact_end(actions->ofpacts, actions->ofpacts_len);
+         pos = ofpact_next(pos)) {
+        if (pos->type == OFPACT_LEARN) {
+            const struct ofpact_learn *learn = ofpact_get_LEARN(pos);
+            if (learn->flags & NX_LEARN_F_DELETE_LEARNED) {
+                return learn;
+            }
+        }
+    }
+
+    return NULL;
+}
+
+static void
+learned_cookies_update__(struct ofproto *ofproto,
+                         const struct rule_actions *actions,
+                         int delta, struct list *dead_cookies)
+    OVS_REQUIRES(ofproto_mutex)
+{
+    if (actions->has_learn_with_delete) {
+        const struct ofpact_learn *learn;
+
+        for (learn = next_learn_with_delete(actions, NULL); learn;
+             learn = next_learn_with_delete(actions, learn)) {
+            learned_cookies_update_one__(ofproto, learn, delta, dead_cookies);
+        }
+    }
+}
+
+static void
+learned_cookies_inc(struct ofproto *ofproto,
+                    const struct rule_actions *actions)
+    OVS_REQUIRES(ofproto_mutex)
+{
+    learned_cookies_update__(ofproto, actions, +1, NULL);
+}
+
+static void
+learned_cookies_dec(struct ofproto *ofproto,
+                    const struct rule_actions *actions,
+                    struct list *dead_cookies)
+    OVS_REQUIRES(ofproto_mutex)
+{
+    learned_cookies_update__(ofproto, actions, -1, dead_cookies);
+}
+
+static void
+learned_cookies_flush(struct ofproto *ofproto, struct list *dead_cookies)
+    OVS_REQUIRES(ofproto_mutex)
 {
-    const struct oftable *rule_table;
+    struct learned_cookie *c, *next;
+
+    LIST_FOR_EACH_SAFE (c, next, u.list_node, dead_cookies) {
+        struct rule_criteria criteria;
+        struct rule_collection rules;
+        struct match match;
 
-    rule_table = &rule->ofproto->tables[rule->table_id];
-    return oftable_is_modifiable(rule_table, flags);
+        match_init_catchall(&match);
+        rule_criteria_init(&criteria, c->table_id, &match, 0,
+                           c->cookie, OVS_BE64_MAX, OFPP_ANY, OFPG_ANY);
+        rule_criteria_require_rw(&criteria, false);
+        collect_rules_loose(ofproto, &criteria, &rules);
+        delete_flows__(&rules, OFPRR_DELETE, NULL);
+        rule_criteria_destroy(&criteria);
+        rule_collection_destroy(&rules);
+
+        list_remove(&c->u.list_node);
+        free(c);
+    }
 }
 \f
 static enum ofperr
@@ -3087,7 +2994,7 @@ handle_port_mod(struct ofconn *ofconn, const struct ofp_header *oh)
         return error;
     }
 
-    error = ofputil_decode_port_mod(oh, &pm);
+    error = ofputil_decode_port_mod(oh, &pm, false);
     if (error) {
         return error;
     }
@@ -3219,55 +3126,62 @@ append_port_stat(struct ofport *port, struct list *replies)
     ofputil_append_port_stat(replies, &ops);
 }
 
-static enum ofperr
-handle_port_stats_request(struct ofconn *ofconn,
-                          const struct ofp_header *request)
+static void
+handle_port_request(struct ofconn *ofconn,
+                    const struct ofp_header *request, ofp_port_t port_no,
+                    void (*cb)(struct ofport *, struct list *replies))
 {
-    struct ofproto *p = ofconn_get_ofproto(ofconn);
+    struct ofproto *ofproto = ofconn_get_ofproto(ofconn);
     struct ofport *port;
     struct list replies;
-    ofp_port_t port_no;
-    enum ofperr error;
-
-    error = ofputil_decode_port_stats_request(request, &port_no);
-    if (error) {
-        return error;
-    }
 
     ofpmp_init(&replies, request);
     if (port_no != OFPP_ANY) {
-        port = ofproto_get_port(p, port_no);
+        port = ofproto_get_port(ofproto, port_no);
         if (port) {
-            append_port_stat(port, &replies);
+            cb(port, &replies);
         }
     } else {
-        HMAP_FOR_EACH (port, hmap_node, &p->ports) {
-            append_port_stat(port, &replies);
+        HMAP_FOR_EACH (port, hmap_node, &ofproto->ports) {
+            cb(port, &replies);
         }
     }
 
     ofconn_send_replies(ofconn, &replies);
-    return 0;
+}
+
+static enum ofperr
+handle_port_stats_request(struct ofconn *ofconn,
+                          const struct ofp_header *request)
+{
+    ofp_port_t port_no;
+    enum ofperr error;
+
+    error = ofputil_decode_port_stats_request(request, &port_no);
+    if (!error) {
+        handle_port_request(ofconn, request, port_no, append_port_stat);
+    }
+    return error;
+}
+
+static void
+append_port_desc(struct ofport *port, struct list *replies)
+{
+    ofputil_append_port_desc_stats_reply(&port->pp, replies);
 }
 
 static enum ofperr
 handle_port_desc_stats_request(struct ofconn *ofconn,
                                const struct ofp_header *request)
 {
-    struct ofproto *p = ofconn_get_ofproto(ofconn);
-    enum ofp_version version;
-    struct ofport *port;
-    struct list replies;
-
-    ofpmp_init(&replies, request);
+    ofp_port_t port_no;
+    enum ofperr error;
 
-    version = ofputil_protocol_to_ofp_version(ofconn_get_protocol(ofconn));
-    HMAP_FOR_EACH (port, hmap_node, &p->ports) {
-        ofputil_append_port_desc_stats_reply(version, &port->pp, &replies);
+    error = ofputil_decode_port_desc_stats_request(request, &port_no);
+    if (!error) {
+        handle_port_request(ofconn, request, port_no, append_port_desc);
     }
-
-    ofconn_send_replies(ofconn, &replies);
-    return 0;
+    return error;
 }
 
 static uint32_t
@@ -3291,22 +3205,6 @@ cookies_remove(struct ofproto *ofproto, struct rule *rule)
     hindex_remove(&ofproto->cookies, &rule->cookie_node);
 }
 
-static void
-ofproto_rule_change_cookie(struct ofproto *ofproto, struct rule *rule,
-                           ovs_be64 new_cookie)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    if (new_cookie != rule->flow_cookie) {
-        cookies_remove(ofproto, rule);
-
-        ovs_mutex_lock(&rule->mutex);
-        rule->flow_cookie = new_cookie;
-        ovs_mutex_unlock(&rule->mutex);
-
-        cookies_insert(ofproto, rule);
-    }
-}
-
 static void
 calc_duration(long long int start, long long int now,
               uint32_t *sec, uint32_t *nsec)
@@ -3384,6 +3282,10 @@ next_matching_table(const struct ofproto *ofproto,
 /* Initializes 'criteria' in a straightforward way based on the other
  * parameters.
  *
+ * By default, the criteria include flows that are read-only, on the assumption
+ * that the collected flows won't be modified.  Call rule_criteria_require_rw()
+ * if flows will be modified.
+ *
  * For "loose" matching, the 'priority' parameter is unimportant and may be
  * supplied as 0. */
 static void
@@ -3398,13 +3300,39 @@ rule_criteria_init(struct rule_criteria *criteria, uint8_t table_id,
     criteria->cookie_mask = cookie_mask;
     criteria->out_port = out_port;
     criteria->out_group = out_group;
-}
-
-static void
-rule_criteria_destroy(struct rule_criteria *criteria)
-{
-    cls_rule_destroy(&criteria->cr);
-}
+
+    /* We ordinarily want to skip hidden rules, but there has to be a way for
+     * code internal to OVS to modify and delete them, so if the criteria
+     * specify a priority that can only be for a hidden flow, then allow hidden
+     * rules to be selected.  (This doesn't allow OpenFlow clients to meddle
+     * with hidden flows because OpenFlow uses only a 16-bit field to specify
+     * priority.) */
+    criteria->include_hidden = priority > UINT16_MAX;
+
+    /* We assume that the criteria are being used to collect flows for reading
+     * but not modification.  Thus, we should collect read-only flows. */
+    criteria->include_readonly = true;
+}
+
+/* By default, criteria initialized by rule_criteria_init() will match flows
+ * that are read-only, on the assumption that the collected flows won't be
+ * modified.  Call this function to match only flows that are be modifiable.
+ *
+ * Specify 'can_write_readonly' as false in ordinary circumstances, true if the
+ * caller has special privileges that allow it to modify even "read-only"
+ * flows. */
+static void
+rule_criteria_require_rw(struct rule_criteria *criteria,
+                         bool can_write_readonly)
+{
+    criteria->include_readonly = can_write_readonly;
+}
+
+static void
+rule_criteria_destroy(struct rule_criteria *criteria)
+{
+    cls_rule_destroy(&criteria->cr);
+}
 
 void
 rule_collection_init(struct rule_collection *rules)
@@ -3464,29 +3392,30 @@ rule_collection_destroy(struct rule_collection *rules)
     }
 }
 
-static enum ofperr
+/* Checks whether 'rule' matches 'c' and, if so, adds it to 'rules'.  This
+ * function verifies most of the criteria in 'c' itself, but the caller must
+ * check 'c->cr' itself.
+ *
+ * Increments '*n_readonly' if 'rule' wasn't added because it's read-only (and
+ * 'c' only includes modifiable rules). */
+static void
 collect_rule(struct rule *rule, const struct rule_criteria *c,
-             struct rule_collection *rules)
+             struct rule_collection *rules, size_t *n_readonly)
     OVS_REQUIRES(ofproto_mutex)
 {
-    /* We ordinarily want to skip hidden rules, but there has to be a way for
-     * code internal to OVS to modify and delete them, so if the criteria
-     * specify a priority that can only be for a hidden flow, then allow hidden
-     * rules to be selected.  (This doesn't allow OpenFlow clients to meddle
-     * with hidden flows because OpenFlow uses only a 16-bit field to specify
-     * priority.) */
-    if (ofproto_rule_is_hidden(rule) && c->cr.priority <= UINT16_MAX) {
-        return 0;
-    } else if (rule->pending) {
-        return OFPROTO_POSTPONE;
-    } else {
-        if ((c->table_id == rule->table_id || c->table_id == 0xff)
-            && ofproto_rule_has_out_port(rule, c->out_port)
-            && ofproto_rule_has_out_group(rule, c->out_group)
-            && !((rule->flow_cookie ^ c->cookie) & c->cookie_mask)) {
+    if ((c->table_id == rule->table_id || c->table_id == 0xff)
+        && ofproto_rule_has_out_port(rule, c->out_port)
+        && ofproto_rule_has_out_group(rule, c->out_group)
+        && !((rule->flow_cookie ^ c->cookie) & c->cookie_mask)
+        && (!rule_is_hidden(rule) || c->include_hidden)) {
+        /* Rule matches all the criteria... */
+        if (!rule_is_readonly(rule) || c->include_readonly) {
+            /* ...add it. */
             rule_collection_add(rules, rule);
+        } else {
+            /* ...except it's read-only. */
+            ++*n_readonly;
         }
-        return 0;
     }
 }
 
@@ -3495,8 +3424,6 @@ collect_rule(struct rule *rule, const struct rule_criteria *c,
  * OFPFC_MODIFY and OFPFC_DELETE requests.  Puts the selected rules on list
  * 'rules'.
  *
- * Hidden rules are always omitted.
- *
  * Returns 0 on success, otherwise an OpenFlow error code. */
 static enum ofperr
 collect_rules_loose(struct ofproto *ofproto,
@@ -3506,6 +3433,7 @@ collect_rules_loose(struct ofproto *ofproto,
 {
     struct oftable *table;
     enum ofperr error = 0;
+    size_t n_readonly = 0;
 
     rule_collection_init(rules);
 
@@ -3521,10 +3449,7 @@ collect_rules_loose(struct ofproto *ofproto,
                                    hash_cookie(criteria->cookie),
                                    &ofproto->cookies) {
             if (cls_rule_is_loose_match(&rule->cr, &criteria->cr.match)) {
-                error = collect_rule(rule, criteria, rules);
-                if (error) {
-                    break;
-                }
+                collect_rule(rule, criteria, rules, &n_readonly);
             }
         }
     } else {
@@ -3535,16 +3460,18 @@ collect_rules_loose(struct ofproto *ofproto,
             fat_rwlock_rdlock(&table->cls.rwlock);
             cls_cursor_init(&cursor, &table->cls, &criteria->cr);
             CLS_CURSOR_FOR_EACH (rule, cr, &cursor) {
-                error = collect_rule(rule, criteria, rules);
-                if (error) {
-                    break;
-                }
+                collect_rule(rule, criteria, rules, &n_readonly);
             }
             fat_rwlock_unlock(&table->cls.rwlock);
         }
     }
 
 exit:
+    if (!error && !rules->n && n_readonly) {
+        /* We didn't find any rules to modify.  We did find some read-only
+         * rules that we're not allowed to modify, so report that. */
+        error = OFPERR_OFPBRC_EPERM;
+    }
     if (error) {
         rule_collection_destroy(rules);
     }
@@ -3556,8 +3483,6 @@ exit:
  * OFPFC_MODIFY_STRICT and OFPFC_DELETE_STRICT requests.  Puts the selected
  * rules on list 'rules'.
  *
- * Hidden rules are always omitted.
- *
  * Returns 0 on success, otherwise an OpenFlow error code. */
 static enum ofperr
 collect_rules_strict(struct ofproto *ofproto,
@@ -3566,6 +3491,7 @@ collect_rules_strict(struct ofproto *ofproto,
     OVS_REQUIRES(ofproto_mutex)
 {
     struct oftable *table;
+    size_t n_readonly = 0;
     int error = 0;
 
     rule_collection_init(rules);
@@ -3582,10 +3508,7 @@ collect_rules_strict(struct ofproto *ofproto,
                                    hash_cookie(criteria->cookie),
                                    &ofproto->cookies) {
             if (cls_rule_equal(&rule->cr, &criteria->cr)) {
-                error = collect_rule(rule, criteria, rules);
-                if (error) {
-                    break;
-                }
+                collect_rule(rule, criteria, rules, &n_readonly);
             }
         }
     } else {
@@ -3597,15 +3520,17 @@ collect_rules_strict(struct ofproto *ofproto,
                                           &table->cls, &criteria->cr));
             fat_rwlock_unlock(&table->cls.rwlock);
             if (rule) {
-                error = collect_rule(rule, criteria, rules);
-                if (error) {
-                    break;
-                }
+                collect_rule(rule, criteria, rules, &n_readonly);
             }
         }
     }
 
 exit:
+    if (!error && !rules->n && n_readonly) {
+        /* We didn't find any rules to modify.  We did find some read-only
+         * rules that we're not allowed to modify, so report that. */
+        error = OFPERR_OFPBRC_EPERM;
+    }
     if (error) {
         rule_collection_destroy(rules);
     }
@@ -3661,7 +3586,7 @@ handle_flow_stats_request(struct ofconn *ofconn,
         long long int now = time_msec();
         struct ofputil_flow_stats fs;
         long long int created, used, modified;
-        struct rule_actions *actions;
+        const struct rule_actions *actions;
         enum ofputil_flow_mod_flags flags;
 
         ovs_mutex_lock(&rule->mutex);
@@ -3702,7 +3627,7 @@ static void
 flow_stats_ds(struct rule *rule, struct ds *results)
 {
     uint64_t packet_count, byte_count;
-    struct rule_actions *actions;
+    const struct rule_actions *actions;
     long long int created, used;
 
     rule->ofproto->ofproto_class->rule_get_stats(rule, &packet_count,
@@ -3950,27 +3875,6 @@ handle_queue_stats_request(struct ofconn *ofconn,
     return error;
 }
 
-static bool
-is_flow_deletion_pending(const struct ofproto *ofproto,
-                         const struct cls_rule *cls_rule,
-                         uint8_t table_id)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    if (!hmap_is_empty(&ofproto->deletions)) {
-        struct ofoperation *op;
-
-        HMAP_FOR_EACH_WITH_HASH (op, hmap_node,
-                                 cls_rule_hash(cls_rule, table_id),
-                                 &ofproto->deletions) {
-            if (cls_rule_equal(cls_rule, &op->rule->cr)) {
-                return true;
-            }
-        }
-    }
-
-    return false;
-}
-
 static bool
 should_evict_a_rule(struct oftable *table, unsigned int extra_space)
     OVS_REQUIRES(ofproto_mutex)
@@ -3980,8 +3884,7 @@ should_evict_a_rule(struct oftable *table, unsigned int extra_space)
 }
 
 static enum ofperr
-evict_rules_from_table(struct ofproto *ofproto, struct oftable *table,
-                       unsigned int extra_space)
+evict_rules_from_table(struct oftable *table, unsigned int extra_space)
     OVS_REQUIRES(ofproto_mutex)
 {
     while (should_evict_a_rule(table, extra_space)) {
@@ -3989,12 +3892,8 @@ evict_rules_from_table(struct ofproto *ofproto, struct oftable *table,
 
         if (!choose_rule_to_evict(table, &rule)) {
             return OFPERR_OFPFMFC_TABLE_FULL;
-        } else if (rule->pending) {
-            return OFPROTO_POSTPONE;
         } else {
-            struct ofopgroup *group = ofopgroup_create_unattached(ofproto);
-            delete_flow__(rule, group, OFPRR_EVICTION);
-            ofopgroup_submit(group);
+            ofproto_rule_delete__(rule, OFPRR_EVICTION);
         }
     }
 
@@ -4014,10 +3913,11 @@ evict_rules_from_table(struct ofproto *ofproto, struct oftable *table,
  * 'ofconn' is used to retrieve the packet buffer specified in ofm->buffer_id,
  * if any. */
 static enum ofperr
-add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
-         struct ofputil_flow_mod *fm, const struct ofp_header *request)
+add_flow(struct ofproto *ofproto, struct ofputil_flow_mod *fm,
+         const struct flow_mod_requester *req)
     OVS_REQUIRES(ofproto_mutex)
 {
+    const struct rule_actions *actions;
     struct oftable *table;
     struct cls_rule cr;
     struct rule *rule;
@@ -4049,8 +3949,8 @@ add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
     }
 
     table = &ofproto->tables[table_id];
-
-    if (!oftable_is_modifiable(table, fm->flags)) {
+    if (table->flags & OFTABLE_READONLY
+        && !(fm->flags & OFPUTIL_FF_NO_READONLY)) {
         return OFPERR_OFPBRC_EPERM;
     }
 
@@ -4069,28 +3969,17 @@ add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
     rule = rule_from_cls_rule(classifier_find_rule_exactly(&table->cls, &cr));
     fat_rwlock_unlock(&table->cls.rwlock);
     if (rule) {
-        cls_rule_destroy(&cr);
-        if (!rule_is_modifiable(rule, fm->flags)) {
-            return OFPERR_OFPBRC_EPERM;
-        } else if (rule->pending) {
-            return OFPROTO_POSTPONE;
-        } else {
-            struct rule_collection rules;
+        struct rule_collection rules;
 
-            rule_collection_init(&rules);
-            rule_collection_add(&rules, rule);
-            fm->modify_cookie = true;
-            error = modify_flows__(ofproto, ofconn, fm, request, &rules);
-            rule_collection_destroy(&rules);
+        cls_rule_destroy(&cr);
 
-            return error;
-        }
-    }
+        rule_collection_init(&rules);
+        rule_collection_add(&rules, rule);
+        fm->modify_cookie = true;
+        error = modify_flows__(ofproto, fm, &rules, req);
+        rule_collection_destroy(&rules);
 
-    /* Serialize against pending deletion. */
-    if (is_flow_deletion_pending(ofproto, &cr, table_id)) {
-        cls_rule_destroy(&cr);
-        return OFPROTO_POSTPONE;
+        return error;
     }
 
     /* Check for overlap, if requested. */
@@ -4108,7 +3997,7 @@ add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
     }
 
     /* If necessary, evict an existing rule to clear out space. */
-    error = evict_rules_from_table(ofproto, table, 1);
+    error = evict_rules_from_table(table, 1);
     if (error) {
         cls_rule_destroy(&cr);
         return error;
@@ -4127,7 +4016,6 @@ add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
     *CONST_CAST(struct ofproto **, &rule->ofproto) = ofproto;
     cls_rule_move(CONST_CAST(struct cls_rule *, &rule->cr), &cr);
     ovs_refcount_init(&rule->ref_count);
-    rule->pending = NULL;
     rule->flow_cookie = fm->new_cookie;
     rule->created = rule->modified = time_msec();
 
@@ -4139,8 +4027,8 @@ add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
 
     *CONST_CAST(uint8_t *, &rule->table_id) = table - ofproto->tables;
     rule->flags = fm->flags & OFPUTIL_FF_STATE;
-    ovsrcu_set(&rule->actions,
-               rule_actions_create(ofproto, fm->ofpacts, fm->ofpacts_len));
+    actions = rule_actions_create(fm->ofpacts, fm->ofpacts_len);
+    ovsrcu_set(&rule->actions, actions);
     list_init(&rule->meter_list_node);
     rule->eviction_group = NULL;
     list_init(&rule->expirable);
@@ -4155,26 +4043,43 @@ add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
         return error;
     }
 
-    /* Insert rule. */
-    do_add_flow(ofproto, ofconn, request, fm->buffer_id, rule);
+    if (fm->hard_timeout || fm->idle_timeout) {
+        list_insert(&ofproto->expirable, &rule->expirable);
+    }
+    cookies_insert(ofproto, rule);
+    eviction_group_add_rule(rule);
+    if (actions->has_meter) {
+        meter_insert_rule(rule);
+    }
 
-    return error;
-}
+    fat_rwlock_wrlock(&table->cls.rwlock);
+    classifier_insert(&table->cls, CONST_CAST(struct cls_rule *, &rule->cr));
+    fat_rwlock_unlock(&table->cls.rwlock);
 
-static void
-do_add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
-            const struct ofp_header *request, uint32_t buffer_id,
-            struct rule *rule)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    struct ofopgroup *group;
+    error = ofproto->ofproto_class->rule_insert(rule);
+    if (error) {
+        oftable_remove_rule(rule);
+        ofproto_rule_unref(rule);
+        return error;
+    }
+    learned_cookies_inc(ofproto, actions);
+
+    if (minimask_get_vid_mask(&rule->cr.match.mask) == VLAN_VID_MASK) {
+        if (ofproto->vlan_bitmap) {
+            uint16_t vid = miniflow_get_vid(&rule->cr.match.flow);
+            if (!bitmap_is_set(ofproto->vlan_bitmap, vid)) {
+                bitmap_set1(ofproto->vlan_bitmap, vid);
+                ofproto->vlans_changed = true;
+            }
+        } else {
+            ofproto->vlans_changed = true;
+        }
+    }
 
-    oftable_insert_rule(rule);
+    ofmonitor_report(ofproto->connmgr, rule, NXFME_ADDED, 0,
+                     req ? req->ofconn : NULL, req ? req->xid : 0);
 
-    group = ofopgroup_create(ofproto, ofconn, request, buffer_id);
-    ofoperation_create(group, rule, OFOPERATION_ADD, 0);
-    ofproto->ofproto_class->rule_insert(rule);
-    ofopgroup_submit(group);
+    return req ? send_buffered_packet(req->ofconn, fm->buffer_id, rule) : 0;
 }
 \f
 /* OFPFC_MODIFY and OFPFC_MODIFY_STRICT. */
@@ -4187,52 +4092,69 @@ do_add_flow(struct ofproto *ofproto, struct ofconn *ofconn,
  *
  * Returns 0 on success, otherwise an OpenFlow error code. */
 static enum ofperr
-modify_flows__(struct ofproto *ofproto, struct ofconn *ofconn,
-               struct ofputil_flow_mod *fm, const struct ofp_header *request,
-               const struct rule_collection *rules)
+modify_flows__(struct ofproto *ofproto, struct ofputil_flow_mod *fm,
+               const struct rule_collection *rules,
+               const struct flow_mod_requester *req)
     OVS_REQUIRES(ofproto_mutex)
 {
-    enum ofoperation_type type;
-    struct ofopgroup *group;
-    enum ofperr error;
+    struct list dead_cookies = LIST_INITIALIZER(&dead_cookies);
+    enum nx_flow_update_event event;
     size_t i;
 
-    type = fm->command == OFPFC_ADD ? OFOPERATION_REPLACE : OFOPERATION_MODIFY;
-    group = ofopgroup_create(ofproto, ofconn, request, fm->buffer_id);
-    error = OFPERR_OFPBRC_EPERM;
+    if (ofproto->ofproto_class->rule_premodify_actions) {
+        for (i = 0; i < rules->n; i++) {
+            struct rule *rule = rules->rules[i];
+            enum ofperr error;
+
+            error = ofproto->ofproto_class->rule_premodify_actions(
+                rule, fm->ofpacts, fm->ofpacts_len);
+            if (error) {
+                return error;
+            }
+        }
+    }
+
+    event = fm->command == OFPFC_ADD ? NXFME_ADDED : NXFME_MODIFIED;
     for (i = 0; i < rules->n; i++) {
         struct rule *rule = rules->rules[i];
-        const struct rule_actions *actions;
-        struct ofoperation *op;
-        bool actions_changed;
-        bool reset_counters;
 
-        /* FIXME: Implement OFPFUTIL_FF_RESET_COUNTS */
+        /*  'fm' says that  */
+        bool change_cookie = (fm->modify_cookie
+                              && fm->new_cookie != OVS_BE64_MAX
+                              && fm->new_cookie != rule->flow_cookie);
 
-        if (rule_is_modifiable(rule, fm->flags)) {
-            /* At least one rule is modifiable, don't report EPERM error. */
-            error = 0;
-        } else {
-            continue;
-        }
+        const struct rule_actions *actions = rule_get_actions(rule);
+        bool change_actions = !ofpacts_equal(fm->ofpacts, fm->ofpacts_len,
+                                             actions->ofpacts,
+                                             actions->ofpacts_len);
 
-        actions = rule_get_actions(rule);
-        actions_changed = !ofpacts_equal(fm->ofpacts, fm->ofpacts_len,
-                                         actions->ofpacts,
-                                         actions->ofpacts_len);
+        bool reset_counters = (fm->flags & OFPUTIL_FF_RESET_COUNTS) != 0;
+
+        long long int now = time_msec();
 
-        op = ofoperation_create(group, rule, type, 0);
+        /* FIXME: Implement OFPFUTIL_FF_RESET_COUNTS */
 
-        if (fm->modify_cookie && fm->new_cookie != OVS_BE64_MAX) {
-            ofproto_rule_change_cookie(ofproto, rule, fm->new_cookie);
+        if (change_cookie) {
+            cookies_remove(ofproto, rule);
         }
-        if (type == OFOPERATION_REPLACE) {
-            ovs_mutex_lock(&rule->mutex);
+
+        ovs_mutex_lock(&rule->mutex);
+        if (fm->command == OFPFC_ADD) {
             rule->idle_timeout = fm->idle_timeout;
             rule->hard_timeout = fm->hard_timeout;
-            ovs_mutex_unlock(&rule->mutex);
-
             rule->flags = fm->flags & OFPUTIL_FF_STATE;
+            rule->created = now;
+        }
+        if (change_cookie) {
+            rule->flow_cookie = fm->new_cookie;
+        }
+        rule->modified = now;
+        ovs_mutex_unlock(&rule->mutex);
+
+        if (change_cookie) {
+            cookies_insert(ofproto, rule);
+        }
+        if (fm->command == OFPFC_ADD) {
             if (fm->idle_timeout || fm->hard_timeout) {
                 if (!rule->eviction_group) {
                     eviction_group_add_rule(rule);
@@ -4242,36 +4164,45 @@ modify_flows__(struct ofproto *ofproto, struct ofconn *ofconn,
             }
         }
 
-        reset_counters = (fm->flags & OFPUTIL_FF_RESET_COUNTS) != 0;
-        if (actions_changed || reset_counters) {
-            struct rule_actions *new_actions;
+        if (change_actions) {
+            ovsrcu_set(&rule->actions, rule_actions_create(fm->ofpacts,
+                                                           fm->ofpacts_len));
+            rule_actions_destroy(actions);
+        }
 
-            op->actions = rule_get_actions(rule);
-            new_actions = rule_actions_create(ofproto,
-                                              fm->ofpacts, fm->ofpacts_len);
+        if (change_actions || reset_counters) {
+            ofproto->ofproto_class->rule_modify_actions(rule, reset_counters);
+        }
 
-            ovsrcu_set(&rule->actions, new_actions);
+        if (event != NXFME_MODIFIED || change_actions || change_cookie) {
+            ofmonitor_report(ofproto->connmgr, rule, event, 0,
+                             req ? req->ofconn : NULL, req ? req->xid : 0);
+        }
 
-            rule->ofproto->ofproto_class->rule_modify_actions(rule,
-                                                              reset_counters);
-        } else {
-            ofoperation_complete(op, 0);
+        if (change_actions) {
+            learned_cookies_inc(ofproto, rule_get_actions(rule));
+            learned_cookies_dec(ofproto, actions, &dead_cookies);
         }
     }
-    ofopgroup_submit(group);
+    learned_cookies_flush(ofproto, &dead_cookies);
 
-    return error;
+    if (fm->buffer_id != UINT32_MAX && req) {
+        return send_buffered_packet(req->ofconn, fm->buffer_id,
+                                    rules->rules[0]);
+    }
+
+    return 0;
 }
 
 static enum ofperr
-modify_flows_add(struct ofproto *ofproto, struct ofconn *ofconn,
-                 struct ofputil_flow_mod *fm, const struct ofp_header *request)
+modify_flows_add(struct ofproto *ofproto, struct ofputil_flow_mod *fm,
+                 const struct flow_mod_requester *req)
     OVS_REQUIRES(ofproto_mutex)
 {
     if (fm->cookie_mask != htonll(0) || fm->new_cookie == OVS_BE64_MAX) {
         return 0;
     }
-    return add_flow(ofproto, ofconn, fm, request);
+    return add_flow(ofproto, fm, req);
 }
 
 /* Implements OFPFC_MODIFY.  Returns 0 on success or an OpenFlow error code on
@@ -4280,9 +4211,8 @@ modify_flows_add(struct ofproto *ofproto, struct ofconn *ofconn,
  * 'ofconn' is used to retrieve the packet buffer specified in fm->buffer_id,
  * if any. */
 static enum ofperr
-modify_flows_loose(struct ofproto *ofproto, struct ofconn *ofconn,
-                   struct ofputil_flow_mod *fm,
-                   const struct ofp_header *request)
+modify_flows_loose(struct ofproto *ofproto, struct ofputil_flow_mod *fm,
+                   const struct flow_mod_requester *req)
     OVS_REQUIRES(ofproto_mutex)
 {
     struct rule_criteria criteria;
@@ -4291,13 +4221,15 @@ modify_flows_loose(struct ofproto *ofproto, struct ofconn *ofconn,
 
     rule_criteria_init(&criteria, fm->table_id, &fm->match, 0,
                        fm->cookie, fm->cookie_mask, OFPP_ANY, OFPG11_ANY);
+    rule_criteria_require_rw(&criteria,
+                             (fm->flags & OFPUTIL_FF_NO_READONLY) != 0);
     error = collect_rules_loose(ofproto, &criteria, &rules);
     rule_criteria_destroy(&criteria);
 
     if (!error) {
         error = (rules.n > 0
-                 ? modify_flows__(ofproto, ofconn, fm, request, &rules)
-                 : modify_flows_add(ofproto, ofconn, fm, request));
+                 ? modify_flows__(ofproto, fm, &rules, req)
+                 : modify_flows_add(ofproto, fm, req));
     }
 
     rule_collection_destroy(&rules);
@@ -4306,14 +4238,10 @@ modify_flows_loose(struct ofproto *ofproto, struct ofconn *ofconn,
 }
 
 /* Implements OFPFC_MODIFY_STRICT.  Returns 0 on success or an OpenFlow error
- * code on failure.
- *
- * 'ofconn' is used to retrieve the packet buffer specified in fm->buffer_id,
- * if any. */
+ * code on failure. */
 static enum ofperr
-modify_flow_strict(struct ofproto *ofproto, struct ofconn *ofconn,
-                   struct ofputil_flow_mod *fm,
-                   const struct ofp_header *request)
+modify_flow_strict(struct ofproto *ofproto, struct ofputil_flow_mod *fm,
+                   const struct flow_mod_requester *req)
     OVS_REQUIRES(ofproto_mutex)
 {
     struct rule_criteria criteria;
@@ -4322,14 +4250,16 @@ modify_flow_strict(struct ofproto *ofproto, struct ofconn *ofconn,
 
     rule_criteria_init(&criteria, fm->table_id, &fm->match, fm->priority,
                        fm->cookie, fm->cookie_mask, OFPP_ANY, OFPG11_ANY);
+    rule_criteria_require_rw(&criteria,
+                             (fm->flags & OFPUTIL_FF_NO_READONLY) != 0);
     error = collect_rules_strict(ofproto, &criteria, &rules);
     rule_criteria_destroy(&criteria);
 
     if (!error) {
         if (rules.n == 0) {
-            error =  modify_flows_add(ofproto, ofconn, fm, request);
+            error = modify_flows_add(ofproto, fm, req);
         } else if (rules.n == 1) {
-            error = modify_flows__(ofproto, ofconn, fm, request, &rules);
+            error = modify_flows__(ofproto, fm, &rules, req);
         }
     }
 
@@ -4340,47 +4270,41 @@ modify_flow_strict(struct ofproto *ofproto, struct ofconn *ofconn,
 \f
 /* OFPFC_DELETE implementation. */
 
+/* Deletes the rules listed in 'rules'. */
 static void
-delete_flow__(struct rule *rule, struct ofopgroup *group,
-              enum ofp_flow_removed_reason reason)
+delete_flows__(const struct rule_collection *rules,
+               enum ofp_flow_removed_reason reason,
+               const struct flow_mod_requester *req)
     OVS_REQUIRES(ofproto_mutex)
 {
-    struct ofproto *ofproto = rule->ofproto;
+    if (rules->n) {
+        struct list dead_cookies = LIST_INITIALIZER(&dead_cookies);
+        struct ofproto *ofproto = rules->rules[0]->ofproto;
+        size_t i;
 
-    ofproto_rule_send_removed(rule, reason);
+        for (i = 0; i < rules->n; i++) {
+            struct rule *rule = rules->rules[i];
+            const struct rule_actions *actions = rule_get_actions(rule);
 
-    ofoperation_create(group, rule, OFOPERATION_DELETE, reason);
-    oftable_remove_rule(rule);
-    ofproto->ofproto_class->rule_delete(rule);
-}
+            ofproto_rule_send_removed(rule, reason);
 
-/* Deletes the rules listed in 'rules'.
- *
- * Returns 0 on success, otherwise an OpenFlow error code. */
-static enum ofperr
-delete_flows__(struct ofproto *ofproto, struct ofconn *ofconn,
-               const struct ofp_header *request,
-               const struct rule_collection *rules,
-               enum ofp_flow_removed_reason reason)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    struct ofopgroup *group;
-    size_t i;
+            ofmonitor_report(ofproto->connmgr, rule, NXFME_DELETED, reason,
+                             req ? req->ofconn : NULL, req ? req->xid : 0);
+            oftable_remove_rule(rule);
+            ofproto->ofproto_class->rule_delete(rule);
 
-    group = ofopgroup_create(ofproto, ofconn, request, UINT32_MAX);
-    for (i = 0; i < rules->n; i++) {
-        delete_flow__(rules->rules[i], group, reason);
+            learned_cookies_dec(ofproto, actions, &dead_cookies);
+        }
+        learned_cookies_flush(ofproto, &dead_cookies);
+        ofmonitor_flush(ofproto->connmgr);
     }
-    ofopgroup_submit(group);
-
-    return 0;
 }
 
 /* Implements OFPFC_DELETE. */
 static enum ofperr
-delete_flows_loose(struct ofproto *ofproto, struct ofconn *ofconn,
+delete_flows_loose(struct ofproto *ofproto,
                    const struct ofputil_flow_mod *fm,
-                   const struct ofp_header *request)
+                   const struct flow_mod_requester *req)
     OVS_REQUIRES(ofproto_mutex)
 {
     struct rule_criteria criteria;
@@ -4390,11 +4314,13 @@ delete_flows_loose(struct ofproto *ofproto, struct ofconn *ofconn,
     rule_criteria_init(&criteria, fm->table_id, &fm->match, 0,
                        fm->cookie, fm->cookie_mask,
                        fm->out_port, fm->out_group);
+    rule_criteria_require_rw(&criteria,
+                             (fm->flags & OFPUTIL_FF_NO_READONLY) != 0);
     error = collect_rules_loose(ofproto, &criteria, &rules);
     rule_criteria_destroy(&criteria);
 
     if (!error && rules.n > 0) {
-        error = delete_flows__(ofproto, ofconn, request, &rules, OFPRR_DELETE);
+        delete_flows__(&rules, fm->delete_reason, req);
     }
     rule_collection_destroy(&rules);
 
@@ -4403,9 +4329,8 @@ delete_flows_loose(struct ofproto *ofproto, struct ofconn *ofconn,
 
 /* Implements OFPFC_DELETE_STRICT. */
 static enum ofperr
-delete_flow_strict(struct ofproto *ofproto, struct ofconn *ofconn,
-                   const struct ofputil_flow_mod *fm,
-                   const struct ofp_header *request)
+delete_flow_strict(struct ofproto *ofproto, const struct ofputil_flow_mod *fm,
+                   const struct flow_mod_requester *req)
     OVS_REQUIRES(ofproto_mutex)
 {
     struct rule_criteria criteria;
@@ -4415,11 +4340,13 @@ delete_flow_strict(struct ofproto *ofproto, struct ofconn *ofconn,
     rule_criteria_init(&criteria, fm->table_id, &fm->match, fm->priority,
                        fm->cookie, fm->cookie_mask,
                        fm->out_port, fm->out_group);
+    rule_criteria_require_rw(&criteria,
+                             (fm->flags & OFPUTIL_FF_NO_READONLY) != 0);
     error = collect_rules_strict(ofproto, &criteria, &rules);
     rule_criteria_destroy(&criteria);
 
     if (!error && rules.n > 0) {
-        error = delete_flows__(ofproto, ofconn, request, &rules, OFPRR_DELETE);
+        delete_flows__(&rules, fm->delete_reason, req);
     }
     rule_collection_destroy(&rules);
 
@@ -4433,7 +4360,7 @@ ofproto_rule_send_removed(struct rule *rule, uint8_t reason)
     struct ofputil_flow_removed fr;
     long long int used;
 
-    if (ofproto_rule_is_hidden(rule) ||
+    if (rule_is_hidden(rule) ||
         !(rule->flags & OFPUTIL_FF_SEND_FLOW_REM)) {
         return;
     }
@@ -4459,21 +4386,13 @@ ofproto_rule_send_removed(struct rule *rule, uint8_t reason)
  * OFPRR_HARD_TIMEOUT or OFPRR_IDLE_TIMEOUT), and then removes 'rule' from its
  * ofproto.
  *
- * 'rule' must not have a pending operation (that is, 'rule->pending' must be
- * NULL).
- *
  * ofproto implementation ->run() functions should use this function to expire
  * OpenFlow flows. */
 void
 ofproto_rule_expire(struct rule *rule, uint8_t reason)
     OVS_REQUIRES(ofproto_mutex)
 {
-    struct ofproto *ofproto = rule->ofproto;
-
-    ovs_assert(reason == OFPRR_HARD_TIMEOUT || reason == OFPRR_IDLE_TIMEOUT
-               || reason == OFPRR_DELETE || reason == OFPRR_GROUP_DELETE);
-
-    ofproto_rule_delete__(ofproto, rule, reason);
+    ofproto_rule_delete__(rule, reason);
 }
 
 /* Reduces '*timeout' to no more than 'max'.  A value of zero in either case
@@ -4521,7 +4440,6 @@ handle_flow_mod(struct ofconn *ofconn, const struct ofp_header *oh)
     uint64_t ofpacts_stub[1024 / 8];
     struct ofpbuf ofpacts;
     enum ofperr error;
-    long long int now;
 
     error = reject_slave_controller(ofconn);
     if (error) {
@@ -4537,37 +4455,17 @@ handle_flow_mod(struct ofconn *ofconn, const struct ofp_header *oh)
         error = ofproto_check_ofpacts(ofproto, fm.ofpacts, fm.ofpacts_len);
     }
     if (!error) {
-        error = handle_flow_mod__(ofproto, ofconn, &fm, oh);
+        struct flow_mod_requester req;
+
+        req.ofconn = ofconn;
+        req.xid = oh->xid;
+        error = handle_flow_mod__(ofproto, &fm, &req);
     }
     if (error) {
         goto exit_free_ofpacts;
     }
 
-    /* Record the operation for logging a summary report. */
-    switch (fm.command) {
-    case OFPFC_ADD:
-        ofproto->n_add++;
-        break;
-
-    case OFPFC_MODIFY:
-    case OFPFC_MODIFY_STRICT:
-        ofproto->n_modify++;
-        break;
-
-    case OFPFC_DELETE:
-    case OFPFC_DELETE_STRICT:
-        ofproto->n_delete++;
-        break;
-    }
-
-    now = time_msec();
-    if (ofproto->next_op_report == LLONG_MAX) {
-        ofproto->first_op = now;
-        ofproto->next_op_report = MAX(now + 10 * 1000,
-                                      ofproto->op_backoff);
-        ofproto->op_backoff = ofproto->next_op_report + 60 * 1000;
-    }
-    ofproto->last_op = now;
+    ofconn_report_flow_mod(ofconn, fm.command);
 
 exit_free_ofpacts:
     ofpbuf_uninit(&ofpacts);
@@ -4576,48 +4474,44 @@ exit:
 }
 
 static enum ofperr
-handle_flow_mod__(struct ofproto *ofproto, struct ofconn *ofconn,
-                  struct ofputil_flow_mod *fm, const struct ofp_header *oh)
+handle_flow_mod__(struct ofproto *ofproto, struct ofputil_flow_mod *fm,
+                  const struct flow_mod_requester *req)
     OVS_EXCLUDED(ofproto_mutex)
 {
     enum ofperr error;
 
     ovs_mutex_lock(&ofproto_mutex);
-    if (ofproto->n_pending < 50) {
-        switch (fm->command) {
-        case OFPFC_ADD:
-            error = add_flow(ofproto, ofconn, fm, oh);
-            break;
+    switch (fm->command) {
+    case OFPFC_ADD:
+        error = add_flow(ofproto, fm, req);
+        break;
 
-        case OFPFC_MODIFY:
-            error = modify_flows_loose(ofproto, ofconn, fm, oh);
-            break;
+    case OFPFC_MODIFY:
+        error = modify_flows_loose(ofproto, fm, req);
+        break;
 
-        case OFPFC_MODIFY_STRICT:
-            error = modify_flow_strict(ofproto, ofconn, fm, oh);
-            break;
+    case OFPFC_MODIFY_STRICT:
+        error = modify_flow_strict(ofproto, fm, req);
+        break;
 
-        case OFPFC_DELETE:
-            error = delete_flows_loose(ofproto, ofconn, fm, oh);
-            break;
+    case OFPFC_DELETE:
+        error = delete_flows_loose(ofproto, fm, req);
+        break;
 
-        case OFPFC_DELETE_STRICT:
-            error = delete_flow_strict(ofproto, ofconn, fm, oh);
-            break;
+    case OFPFC_DELETE_STRICT:
+        error = delete_flow_strict(ofproto, fm, req);
+        break;
 
-        default:
-            if (fm->command > 0xff) {
-                VLOG_WARN_RL(&rl, "%s: flow_mod has explicit table_id but "
-                             "flow_mod_table_id extension is not enabled",
-                             ofproto->name);
-            }
-            error = OFPERR_OFPFMFC_BAD_COMMAND;
-            break;
+    default:
+        if (fm->command > 0xff) {
+            VLOG_WARN_RL(&rl, "%s: flow_mod has explicit table_id but "
+                         "flow_mod_table_id extension is not enabled",
+                         ofproto->name);
         }
-    } else {
-        ovs_assert(!list_is_empty(&ofproto->pending));
-        error = OFPROTO_POSTPONE;
+        error = OFPERR_OFPFMFC_BAD_COMMAND;
+        break;
     }
+    ofmonitor_flush(ofproto->connmgr);
     ovs_mutex_unlock(&ofproto_mutex);
 
     run_rule_executes(ofproto);
@@ -4638,11 +4532,6 @@ handle_role_request(struct ofconn *ofconn, const struct ofp_header *oh)
     }
 
     if (request.role != OFPCR12_ROLE_NOCHANGE) {
-        if (ofconn_get_role(ofconn) != request.role
-            && ofconn_has_pending_opgroups(ofconn)) {
-            return OFPROTO_POSTPONE;
-        }
-
         if (request.have_generation_id
             && !ofconn_set_master_election_id(ofconn, request.generation_id)) {
                 return OFPERR_OFPRRFC_STALE;
@@ -4688,12 +4577,8 @@ handle_nxt_set_flow_format(struct ofconn *ofconn, const struct ofp_header *oh)
 
     cur = ofconn_get_protocol(ofconn);
     next = ofputil_protocol_set_base(cur, next_base);
-    if (cur != next && ofconn_has_pending_opgroups(ofconn)) {
-        /* Avoid sending async messages in surprising protocol. */
-        return OFPROTO_POSTPONE;
-    }
-
     ofconn_set_protocol(ofconn, next);
+
     return 0;
 }
 
@@ -4709,12 +4594,6 @@ handle_nxt_set_packet_in_format(struct ofconn *ofconn,
         return OFPERR_OFPBRC_EPERM;
     }
 
-    if (format != ofconn_get_packet_in_format(ofconn)
-        && ofconn_has_pending_opgroups(ofconn)) {
-        /* Avoid sending async message in surprsing packet in format. */
-        return OFPROTO_POSTPONE;
-    }
-
     ofconn_set_packet_in_format(ofconn, format);
     return 0;
 }
@@ -4787,10 +4666,6 @@ handle_barrier_request(struct ofconn *ofconn, const struct ofp_header *oh)
 {
     struct ofpbuf *buf;
 
-    if (ofconn_has_pending_opgroups(ofconn)) {
-        return OFPROTO_POSTPONE;
-    }
-
     buf = ofpraw_alloc_reply((oh->version == OFP10_VERSION
                               ? OFPRAW_OFPT10_BARRIER_REPLY
                               : OFPRAW_OFPT11_BARRIER_REPLY), oh, 0);
@@ -4804,17 +4679,10 @@ ofproto_compose_flow_refresh_update(const struct rule *rule,
                                     struct list *msgs)
     OVS_REQUIRES(ofproto_mutex)
 {
-    struct ofoperation *op = rule->pending;
     const struct rule_actions *actions;
     struct ofputil_flow_update fu;
     struct match match;
 
-    if (op && op->type == OFOPERATION_ADD) {
-        /* We'll report the final flow when the operation completes.  Reporting
-         * it now would cause a duplicate report later. */
-        return;
-    }
-
     fu.event = (flags & (NXFMF_INITIAL | NXFMF_ADD)
                 ? NXFME_ADDED : NXFME_MODIFIED);
     fu.reason = 0;
@@ -4828,30 +4696,7 @@ ofproto_compose_flow_refresh_update(const struct rule *rule,
     fu.match = &match;
     fu.priority = rule->cr.priority;
 
-    if (!(flags & NXFMF_ACTIONS)) {
-        actions = NULL;
-    } else if (!op) {
-        actions = rule_get_actions(rule);
-    } else {
-        /* An operation is in progress.  Use the previous version of the flow's
-         * actions, so that when the operation commits we report the change. */
-        switch (op->type) {
-        case OFOPERATION_ADD:
-            OVS_NOT_REACHED();
-
-        case OFOPERATION_MODIFY:
-        case OFOPERATION_REPLACE:
-            actions = op->actions ? op->actions : rule_get_actions(rule);
-            break;
-
-        case OFOPERATION_DELETE:
-            actions = rule_get_actions(rule);
-            break;
-
-        default:
-            OVS_NOT_REACHED();
-        }
-    }
+    actions = flags & NXFMF_ACTIONS ? rule_get_actions(rule) : NULL;
     fu.ofpacts = actions ? actions->ofpacts : NULL;
     fu.ofpacts_len = actions ? actions->ofpacts_len : 0;
 
@@ -4885,13 +4730,11 @@ ofproto_collect_ofmonitor_refresh_rule(const struct ofmonitor *m,
 {
     enum nx_flow_monitor_flags update;
 
-    if (ofproto_rule_is_hidden(rule)) {
+    if (rule_is_hidden(rule)) {
         return;
     }
 
-    if (!(rule->pending
-          ? ofoperation_has_out_port(rule->pending, m->out_port)
-          : ofproto_rule_has_out_port(rule, m->out_port))) {
+    if (!ofproto_rule_has_out_port(rule, m->out_port)) {
         return;
     }
 
@@ -4924,7 +4767,6 @@ ofproto_collect_ofmonitor_refresh_rules(const struct ofmonitor *m,
     OVS_REQUIRES(ofproto_mutex)
 {
     const struct ofproto *ofproto = ofconn_get_ofproto(m->ofconn);
-    const struct ofoperation *op;
     const struct oftable *table;
     struct cls_rule target;
 
@@ -4936,22 +4778,10 @@ ofproto_collect_ofmonitor_refresh_rules(const struct ofmonitor *m,
         fat_rwlock_rdlock(&table->cls.rwlock);
         cls_cursor_init(&cursor, &table->cls, &target);
         CLS_CURSOR_FOR_EACH (rule, cr, &cursor) {
-            ovs_assert(!rule->pending); /* XXX */
             ofproto_collect_ofmonitor_refresh_rule(m, rule, seqno, rules);
         }
         fat_rwlock_unlock(&table->cls.rwlock);
     }
-
-    HMAP_FOR_EACH (op, hmap_node, &ofproto->deletions) {
-        struct rule *rule = op->rule;
-
-        if (((m->table_id == 0xff
-              ? !(ofproto->tables[rule->table_id].flags & OFTABLE_HIDDEN)
-              : m->table_id == rule->table_id))
-            && cls_rule_is_loose_match(&rule->cr, &target.match)) {
-            ofproto_collect_ofmonitor_refresh_rule(m, rule, seqno, rules);
-        }
-    }
     cls_rule_destroy(&target);
 }
 
@@ -5065,7 +4895,7 @@ handle_flow_monitor_cancel(struct ofconn *ofconn, const struct ofp_header *oh)
         ofmonitor_destroy(m);
         error = 0;
     } else {
-        error = OFPERR_NXBRC_FM_BAD_ID;
+        error = OFPERR_OFPMOFC_UNKNOWN_MONITOR;
     }
     ovs_mutex_unlock(&ofproto_mutex);
 
@@ -5075,8 +4905,6 @@ handle_flow_monitor_cancel(struct ofconn *ofconn, const struct ofp_header *oh)
 /* Meters implementation.
  *
  * Meter table entry, indexed by the OpenFlow meter_id.
- * These are always dynamically allocated to allocate enough space for
- * the bands.
  * 'created' is used to compute the duration for meter stats.
  * 'list rules' is needed so that we can delete the dependent rules when the
  * meter table entry is deleted.
@@ -5108,6 +4936,18 @@ get_provider_meter_id(const struct ofproto *ofproto, uint32_t of_meter_id)
     return UINT32_MAX;
 }
 
+/* Finds the meter invoked by 'rule''s actions and adds 'rule' to the meter's
+ * list of rules. */
+static void
+meter_insert_rule(struct rule *rule)
+{
+    const struct rule_actions *a = rule_get_actions(rule);
+    uint32_t meter_id = ofpacts_get_meter(a->ofpacts, a->ofpacts_len);
+    struct meter *meter = rule->ofproto->meters[meter_id];
+
+    list_insert(&meter->rules, &rule->meter_list_node);
+}
+
 static void
 meter_update(struct meter *meter, const struct ofputil_meter_config *config)
 {
@@ -5195,8 +5035,7 @@ handle_modify_meter(struct ofproto *ofproto, struct ofputil_meter_mod *mm)
 }
 
 static enum ofperr
-handle_delete_meter(struct ofconn *ofconn, const struct ofp_header *oh,
-                    struct ofputil_meter_mod *mm)
+handle_delete_meter(struct ofconn *ofconn, struct ofputil_meter_mod *mm)
     OVS_EXCLUDED(ofproto_mutex)
 {
     struct ofproto *ofproto = ofconn_get_ofproto(ofconn);
@@ -5225,22 +5064,17 @@ handle_delete_meter(struct ofconn *ofconn, const struct ofp_header *oh,
             struct rule *rule;
 
             LIST_FOR_EACH (rule, meter_list_node, &meter->rules) {
-                if (rule->pending) {
-                    error = OFPROTO_POSTPONE;
-                    goto exit;
-                }
                 rule_collection_add(&rules, rule);
             }
         }
     }
     if (rules.n > 0) {
-        delete_flows__(ofproto, ofconn, oh, &rules, OFPRR_METER_DELETE);
+        delete_flows__(&rules, OFPRR_METER_DELETE, NULL);
     }
 
     /* Delete the meters. */
     meter_delete(ofproto, first, last);
 
-exit:
     ovs_mutex_unlock(&ofproto_mutex);
     rule_collection_destroy(&rules);
 
@@ -5296,7 +5130,7 @@ handle_meter_mod(struct ofconn *ofconn, const struct ofp_header *oh)
         break;
 
     case OFPMC13_DELETE:
-        error = handle_delete_meter(ofconn, oh, &mm);
+        error = handle_delete_meter(ofconn, &mm);
         break;
 
     default:
@@ -5395,47 +5229,38 @@ handle_meter_request(struct ofconn *ofconn, const struct ofp_header *request,
     return 0;
 }
 
-bool
-ofproto_group_lookup(const struct ofproto *ofproto, uint32_t group_id,
-                     struct ofgroup **group)
-    OVS_TRY_RDLOCK(true, (*group)->rwlock)
+static bool
+ofproto_group_lookup__(const struct ofproto *ofproto, uint32_t group_id,
+                       struct ofgroup **group)
+    OVS_REQ_RDLOCK(ofproto->groups_rwlock)
 {
-    ovs_rwlock_rdlock(&ofproto->groups_rwlock);
     HMAP_FOR_EACH_IN_BUCKET (*group, hmap_node,
                              hash_int(group_id, 0), &ofproto->groups) {
         if ((*group)->group_id == group_id) {
-            ovs_rwlock_rdlock(&(*group)->rwlock);
-            ovs_rwlock_unlock(&ofproto->groups_rwlock);
             return true;
         }
     }
-    ovs_rwlock_unlock(&ofproto->groups_rwlock);
+
     return false;
 }
 
-void
-ofproto_group_release(struct ofgroup *group)
-    OVS_RELEASES(group->rwlock)
+/* If the group exists, this function increments the groups's reference count.
+ *
+ * Make sure to call ofproto_group_unref() after no longer needing to maintain
+ * a reference to the group. */
+bool
+ofproto_group_lookup(const struct ofproto *ofproto, uint32_t group_id,
+                     struct ofgroup **group)
 {
-    ovs_rwlock_unlock(&group->rwlock);
-}
+    bool found;
 
-static bool
-ofproto_group_write_lookup(const struct ofproto *ofproto, uint32_t group_id,
-                           struct ofgroup **group)
-    OVS_TRY_WRLOCK(true, ofproto->groups_rwlock)
-    OVS_TRY_WRLOCK(true, (*group)->rwlock)
-{
-    ovs_rwlock_wrlock(&ofproto->groups_rwlock);
-    HMAP_FOR_EACH_IN_BUCKET (*group, hmap_node,
-                             hash_int(group_id, 0), &ofproto->groups) {
-        if ((*group)->group_id == group_id) {
-            ovs_rwlock_wrlock(&(*group)->rwlock);
-            return true;
-        }
+    ovs_rwlock_rdlock(&ofproto->groups_rwlock);
+    found = ofproto_group_lookup__(ofproto, group_id, group);
+    if (found) {
+        ofproto_group_ref(*group);
     }
     ovs_rwlock_unlock(&ofproto->groups_rwlock);
-    return false;
+    return found;
 }
 
 static bool
@@ -5470,7 +5295,7 @@ static uint32_t
 group_get_ref_count(struct ofgroup *group)
     OVS_EXCLUDED(ofproto_mutex)
 {
-    struct ofproto *ofproto = group->ofproto;
+    struct ofproto *ofproto = CONST_CAST(struct ofproto *, group->ofproto);
     struct rule_criteria criteria;
     struct rule_collection rules;
     struct match match;
@@ -5493,10 +5318,9 @@ group_get_ref_count(struct ofgroup *group)
 
 static void
 append_group_stats(struct ofgroup *group, struct list *replies)
-    OVS_REQ_RDLOCK(group->rwlock)
 {
     struct ofputil_group_stats ogs;
-    struct ofproto *ofproto = group->ofproto;
+    const struct ofproto *ofproto = group->ofproto;
     long long int now = time_msec();
     int error;
 
@@ -5524,64 +5348,64 @@ append_group_stats(struct ofgroup *group, struct list *replies)
     free(ogs.bucket_stats);
 }
 
-static enum ofperr
-handle_group_stats_request(struct ofconn *ofconn,
-                           const struct ofp_header *request)
+static void
+handle_group_request(struct ofconn *ofconn,
+                     const struct ofp_header *request, uint32_t group_id,
+                     void (*cb)(struct ofgroup *, struct list *replies))
 {
     struct ofproto *ofproto = ofconn_get_ofproto(ofconn);
-    struct list replies;
-    enum ofperr error;
     struct ofgroup *group;
-    uint32_t group_id;
-
-    error = ofputil_decode_group_stats_request(request, &group_id);
-    if (error) {
-        return error;
-    }
+    struct list replies;
 
     ofpmp_init(&replies, request);
-
     if (group_id == OFPG_ALL) {
         ovs_rwlock_rdlock(&ofproto->groups_rwlock);
         HMAP_FOR_EACH (group, hmap_node, &ofproto->groups) {
-            ovs_rwlock_rdlock(&group->rwlock);
-            append_group_stats(group, &replies);
-            ovs_rwlock_unlock(&group->rwlock);
+            cb(group, &replies);
         }
         ovs_rwlock_unlock(&ofproto->groups_rwlock);
     } else {
         if (ofproto_group_lookup(ofproto, group_id, &group)) {
-            append_group_stats(group, &replies);
-            ofproto_group_release(group);
+            cb(group, &replies);
+            ofproto_group_unref(group);
         }
     }
-
     ofconn_send_replies(ofconn, &replies);
-
-    return 0;
 }
 
 static enum ofperr
-handle_group_desc_stats_request(struct ofconn *ofconn,
-                                const struct ofp_header *request)
+handle_group_stats_request(struct ofconn *ofconn,
+                           const struct ofp_header *request)
 {
-    struct ofproto *ofproto = ofconn_get_ofproto(ofconn);
-    struct list replies;
-    struct ofputil_group_desc gds;
-    struct ofgroup *group;
-
-    ofpmp_init(&replies, request);
+    uint32_t group_id;
+    enum ofperr error;
 
-    ovs_rwlock_rdlock(&ofproto->groups_rwlock);
-    HMAP_FOR_EACH (group, hmap_node, &ofproto->groups) {
-        gds.group_id = group->group_id;
-        gds.type = group->type;
-        ofputil_append_group_desc_reply(&gds, &group->buckets, &replies);
+    error = ofputil_decode_group_stats_request(request, &group_id);
+    if (error) {
+        return error;
     }
-    ovs_rwlock_unlock(&ofproto->groups_rwlock);
 
-    ofconn_send_replies(ofconn, &replies);
+    handle_group_request(ofconn, request, group_id, append_group_stats);
+    return 0;
+}
+
+static void
+append_group_desc(struct ofgroup *group, struct list *replies)
+{
+    struct ofputil_group_desc gds;
 
+    gds.group_id = group->group_id;
+    gds.type = group->type;
+    ofputil_append_group_desc_reply(&gds, &group->buckets, replies);
+}
+
+static enum ofperr
+handle_group_desc_stats_request(struct ofconn *ofconn,
+                                const struct ofp_header *request)
+{
+    handle_group_request(ofconn, request,
+                         ofputil_decode_group_desc_request(request),
+                         append_group_desc);
     return 0;
 }
 
@@ -5643,24 +5467,12 @@ handle_queue_get_config_request(struct ofconn *ofconn,
    return 0;
 }
 
-/* Implements OFPGC11_ADD
- * in which no matching flow already exists in the flow table.
- *
- * Adds the flow specified by 'ofm', which is followed by 'n_actions'
- * ofp_actions, to the ofproto's flow table.  Returns 0 on success, an OpenFlow
- * error code on failure, or OFPROTO_POSTPONE if the operation cannot be
- * initiated now but may be retried later.
- *
- * Upon successful return, takes ownership of 'fm->ofpacts'.  On failure,
- * ownership remains with the caller.
- *
- * 'ofconn' is used to retrieve the packet buffer specified in ofm->buffer_id,
- * if any. */
 static enum ofperr
-add_group(struct ofproto *ofproto, struct ofputil_group_mod *gm)
+init_group(struct ofproto *ofproto, struct ofputil_group_mod *gm,
+           struct ofgroup **ofgroup)
 {
-    struct ofgroup *ofgroup;
     enum ofperr error;
+    const long long int now = time_msec();
 
     if (gm->group_id > OFPG_MAX) {
         return OFPERR_OFPGMFC_INVALID_GROUP;
@@ -5669,26 +5481,45 @@ add_group(struct ofproto *ofproto, struct ofputil_group_mod *gm)
         return OFPERR_OFPGMFC_BAD_TYPE;
     }
 
-    /* Allocate new group and initialize it. */
-    ofgroup = ofproto->ofproto_class->group_alloc();
-    if (!ofgroup) {
-        VLOG_WARN_RL(&rl, "%s: failed to create group", ofproto->name);
+    *ofgroup = ofproto->ofproto_class->group_alloc();
+    if (!*ofgroup) {
+        VLOG_WARN_RL(&rl, "%s: failed to allocate group", ofproto->name);
         return OFPERR_OFPGMFC_OUT_OF_GROUPS;
     }
 
-    ovs_rwlock_init(&ofgroup->rwlock);
-    ofgroup->ofproto  = ofproto;
-    ofgroup->group_id = gm->group_id;
-    ofgroup->type     = gm->type;
-    ofgroup->created = ofgroup->modified = time_msec();
+    (*ofgroup)->ofproto = ofproto;
+    *CONST_CAST(uint32_t *, &((*ofgroup)->group_id)) = gm->group_id;
+    *CONST_CAST(enum ofp11_group_type *, &(*ofgroup)->type) = gm->type;
+    *CONST_CAST(long long int *, &((*ofgroup)->created)) = now;
+    *CONST_CAST(long long int *, &((*ofgroup)->modified)) = now;
+    ovs_refcount_init(&(*ofgroup)->ref_count);
 
-    list_move(&ofgroup->buckets, &gm->buckets);
-    ofgroup->n_buckets = list_size(&ofgroup->buckets);
+    list_move(&(*ofgroup)->buckets, &gm->buckets);
+    *CONST_CAST(uint32_t *, &(*ofgroup)->n_buckets) =
+        list_size(&(*ofgroup)->buckets);
 
     /* Construct called BEFORE any locks are held. */
-    error = ofproto->ofproto_class->group_construct(ofgroup);
+    error = ofproto->ofproto_class->group_construct(*ofgroup);
+    if (error) {
+        ofputil_bucket_list_destroy(&(*ofgroup)->buckets);
+        ofproto->ofproto_class->group_dealloc(*ofgroup);
+    }
+    return error;
+}
+
+/* Implements the OFPGC11_ADD operation specified by 'gm', adding a group to
+ * 'ofproto''s group table.  Returns 0 on success or an OpenFlow error code on
+ * failure. */
+static enum ofperr
+add_group(struct ofproto *ofproto, struct ofputil_group_mod *gm)
+{
+    struct ofgroup *ofgroup;
+    enum ofperr error;
+
+    /* Allocate new group and initialize it. */
+    error = init_group(ofproto, gm, &ofgroup);
     if (error) {
-        goto free_out;
+        return error;
     }
 
     /* We wrlock as late as possible to minimize the time we jam any other
@@ -5718,76 +5549,66 @@ add_group(struct ofproto *ofproto, struct ofputil_group_mod *gm)
  unlock_out:
     ovs_rwlock_unlock(&ofproto->groups_rwlock);
     ofproto->ofproto_class->group_destruct(ofgroup);
- free_out:
     ofputil_bucket_list_destroy(&ofgroup->buckets);
     ofproto->ofproto_class->group_dealloc(ofgroup);
 
     return error;
 }
 
-/* Implements OFPFC_MODIFY.  Returns 0 on success or an OpenFlow error code on
- * failure.
+/* Implements OFPGC11_MODIFY.  Returns 0 on success or an OpenFlow error code
+ * on failure.
  *
- * 'ofconn' is used to retrieve the packet buffer specified in fm->buffer_id,
- * if any. */
+ * Note that the group is re-created and then replaces the old group in
+ * ofproto's ofgroup hash map. Thus, the group is never altered while users of
+ * the xlate module hold a pointer to the group. */
 static enum ofperr
 modify_group(struct ofproto *ofproto, struct ofputil_group_mod *gm)
 {
-    struct ofgroup *ofgroup;
-    struct ofgroup *victim;
+    struct ofgroup *ofgroup, *new_ofgroup, *retiring;
     enum ofperr error;
 
-    if (gm->group_id > OFPG_MAX) {
-        return OFPERR_OFPGMFC_INVALID_GROUP;
+    error = init_group(ofproto, gm, &new_ofgroup);
+    if (error) {
+        return error;
     }
 
-    if (gm->type > OFPGT11_FF) {
-        return OFPERR_OFPGMFC_BAD_TYPE;
-    }
+    retiring = new_ofgroup;
 
-    victim = ofproto->ofproto_class->group_alloc();
-    if (!victim) {
-        VLOG_WARN_RL(&rl, "%s: failed to allocate group", ofproto->name);
-        return OFPERR_OFPGMFC_OUT_OF_GROUPS;
-    }
-
-    if (!ofproto_group_write_lookup(ofproto, gm->group_id, &ofgroup)) {
+    ovs_rwlock_wrlock(&ofproto->groups_rwlock);
+    if (!ofproto_group_lookup__(ofproto, gm->group_id, &ofgroup)) {
         error = OFPERR_OFPGMFC_UNKNOWN_GROUP;
-        goto free_out;
+        goto out;
     }
-    /* Both group's and its container's write locks held now.
-     * Also, n_groups[] is protected by ofproto->groups_rwlock. */
+
+    /* Ofproto's group write lock is held now. */
     if (ofgroup->type != gm->type
         && ofproto->n_groups[gm->type] >= ofproto->ogf.max_groups[gm->type]) {
         error = OFPERR_OFPGMFC_OUT_OF_GROUPS;
-        goto unlock_out;
+        goto out;
     }
 
-    *victim = *ofgroup;
-    list_move(&victim->buckets, &ofgroup->buckets);
+    /* The group creation time does not change during modification. */
+    *CONST_CAST(long long int *, &(new_ofgroup->created)) = ofgroup->created;
+    *CONST_CAST(long long int *, &(new_ofgroup->modified)) = time_msec();
 
-    ofgroup->type = gm->type;
-    list_move(&ofgroup->buckets, &gm->buckets);
-    ofgroup->n_buckets = list_size(&ofgroup->buckets);
-
-    error = ofproto->ofproto_class->group_modify(ofgroup, victim);
-    if (!error) {
-        ofputil_bucket_list_destroy(&victim->buckets);
-        ofproto->n_groups[victim->type]--;
-        ofproto->n_groups[ofgroup->type]++;
-        ofgroup->modified = time_msec();
-    } else {
-        ofputil_bucket_list_destroy(&ofgroup->buckets);
+    error = ofproto->ofproto_class->group_modify(new_ofgroup);
+    if (error) {
+        goto out;
+    }
 
-        *ofgroup = *victim;
-        list_move(&ofgroup->buckets, &victim->buckets);
+    retiring = ofgroup;
+    /* Replace ofgroup in ofproto's groups hash map with new_ofgroup. */
+    hmap_remove(&ofproto->groups, &ofgroup->hmap_node);
+    hmap_insert(&ofproto->groups, &new_ofgroup->hmap_node,
+                hash_int(new_ofgroup->group_id, 0));
+    if (ofgroup->type != new_ofgroup->type) {
+        ofproto->n_groups[ofgroup->type]--;
+        ofproto->n_groups[new_ofgroup->type]++;
     }
 
- unlock_out:
-    ovs_rwlock_unlock(&ofgroup->rwlock);
+out:
+    ofproto_group_unref(retiring);
     ovs_rwlock_unlock(&ofproto->groups_rwlock);
- free_out:
-    ofproto->ofproto_class->group_dealloc(victim);
     return error;
 }
 
@@ -5801,25 +5622,18 @@ delete_group__(struct ofproto *ofproto, struct ofgroup *ofgroup)
     /* Delete all flow entries containing this group in a group action */
     match_init_catchall(&match);
     flow_mod_init(&fm, &match, 0, NULL, 0, OFPFC_DELETE);
+    fm.delete_reason = OFPRR_GROUP_DELETE;
     fm.out_group = ofgroup->group_id;
-    handle_flow_mod__(ofproto, NULL, &fm, NULL);
+    handle_flow_mod__(ofproto, &fm, NULL);
 
-    /* Must wait until existing readers are done,
-     * while holding the container's write lock at the same time. */
-    ovs_rwlock_wrlock(&ofgroup->rwlock);
     hmap_remove(&ofproto->groups, &ofgroup->hmap_node);
     /* No-one can find this group any more. */
     ofproto->n_groups[ofgroup->type]--;
     ovs_rwlock_unlock(&ofproto->groups_rwlock);
-
-    ofproto->ofproto_class->group_destruct(ofgroup);
-    ofputil_bucket_list_destroy(&ofgroup->buckets);
-    ovs_rwlock_unlock(&ofgroup->rwlock);
-    ovs_rwlock_destroy(&ofgroup->rwlock);
-    ofproto->ofproto_class->group_dealloc(ofgroup);
+    ofproto_group_unref(ofgroup);
 }
 
-/* Implements OFPGC_DELETE. */
+/* Implements OFPGC11_DELETE. */
 static void
 delete_group(struct ofproto *ofproto, uint32_t group_id)
 {
@@ -5939,6 +5753,69 @@ handle_table_mod(struct ofconn *ofconn, const struct ofp_header *oh)
     return table_mod(ofproto, &tm);
 }
 
+static enum ofperr
+handle_bundle_control(struct ofconn *ofconn, const struct ofp_header *oh)
+{
+    enum ofperr error;
+    struct ofputil_bundle_ctrl_msg bctrl;
+    struct ofpbuf *buf;
+    struct ofputil_bundle_ctrl_msg reply;
+
+    error = ofputil_decode_bundle_ctrl(oh, &bctrl);
+    if (error) {
+        return error;
+    }
+    reply.flags = 0;
+    reply.bundle_id = bctrl.bundle_id;
+
+    switch (bctrl.type) {
+        case OFPBCT_OPEN_REQUEST:
+        error = ofp_bundle_open(ofconn, bctrl.bundle_id, bctrl.flags);
+        reply.type = OFPBCT_OPEN_REPLY;
+        break;
+    case OFPBCT_CLOSE_REQUEST:
+        error = ofp_bundle_close(ofconn, bctrl.bundle_id, bctrl.flags);
+        reply.type = OFPBCT_CLOSE_REPLY;;
+        break;
+    case OFPBCT_COMMIT_REQUEST:
+        error = ofp_bundle_commit(ofconn, bctrl.bundle_id, bctrl.flags);
+        reply.type = OFPBCT_COMMIT_REPLY;
+        break;
+    case OFPBCT_DISCARD_REQUEST:
+        error = ofp_bundle_discard(ofconn, bctrl.bundle_id);
+        reply.type = OFPBCT_DISCARD_REPLY;
+        break;
+
+    case OFPBCT_OPEN_REPLY:
+    case OFPBCT_CLOSE_REPLY:
+    case OFPBCT_COMMIT_REPLY:
+    case OFPBCT_DISCARD_REPLY:
+        return OFPERR_OFPBFC_BAD_TYPE;
+        break;
+    }
+
+    if (!error) {
+        buf = ofputil_encode_bundle_ctrl_reply(oh, &reply);
+        ofconn_send_reply(ofconn, buf);
+    }
+    return error;
+}
+
+
+static enum ofperr
+handle_bundle_add(struct ofconn *ofconn, const struct ofp_header *oh)
+{
+    enum ofperr error;
+    struct ofputil_bundle_add_msg badd;
+
+    error = ofputil_decode_bundle_add(oh, &badd);
+    if (error) {
+        return error;
+    }
+
+    return ofp_bundle_add_message(ofconn, &badd);
+}
+
 static enum ofperr
 handle_openflow__(struct ofconn *ofconn, const struct ofpbuf *msg)
     OVS_EXCLUDED(ofproto_mutex)
@@ -6071,6 +5948,12 @@ handle_openflow__(struct ofconn *ofconn, const struct ofpbuf *msg)
     case OFPTYPE_QUEUE_GET_CONFIG_REQUEST:
         return handle_queue_get_config_request(ofconn, oh);
 
+    case OFPTYPE_BUNDLE_CONTROL:
+        return handle_bundle_control(ofconn, oh);
+
+    case OFPTYPE_BUNDLE_ADD_MESSAGE:
+        return handle_bundle_add(ofconn, oh);
+
     case OFPTYPE_HELLO:
     case OFPTYPE_ERROR:
     case OFPTYPE_FEATURES_REPLY:
@@ -6110,377 +5993,50 @@ handle_openflow__(struct ofconn *ofconn, const struct ofpbuf *msg)
     }
 }
 
-static bool
+static void
 handle_openflow(struct ofconn *ofconn, const struct ofpbuf *ofp_msg)
     OVS_EXCLUDED(ofproto_mutex)
 {
     int error = handle_openflow__(ofconn, ofp_msg);
-    if (error && error != OFPROTO_POSTPONE) {
+    if (error) {
         ofconn_send_error(ofconn, ofpbuf_data(ofp_msg), error);
     }
     COVERAGE_INC(ofproto_recv_openflow);
-    return error != OFPROTO_POSTPONE;
 }
 \f
 /* Asynchronous operations. */
 
-/* Creates and returns a new ofopgroup that is not associated with any
- * OpenFlow connection.
- *
- * The caller should add operations to the returned group with
- * ofoperation_create() and then submit it with ofopgroup_submit(). */
-static struct ofopgroup *
-ofopgroup_create_unattached(struct ofproto *ofproto)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    struct ofopgroup *group = xzalloc(sizeof *group);
-    group->ofproto = ofproto;
-    list_init(&group->ofproto_node);
-    list_init(&group->ops);
-    list_init(&group->ofconn_node);
-    return group;
-}
-
-/* Creates and returns a new ofopgroup for 'ofproto'.
- *
- * If 'ofconn' is NULL, the new ofopgroup is not associated with any OpenFlow
- * connection.  The 'request' and 'buffer_id' arguments are ignored.
- *
- * If 'ofconn' is nonnull, then the new ofopgroup is associated with 'ofconn'.
- * If the ofopgroup eventually fails, then the error reply will include
- * 'request'.  If the ofopgroup eventually succeeds, then the packet with
- * buffer id 'buffer_id' on 'ofconn' will be sent by 'ofconn''s ofproto.
- *
- * The caller should add operations to the returned group with
- * ofoperation_create() and then submit it with ofopgroup_submit(). */
-static struct ofopgroup *
-ofopgroup_create(struct ofproto *ofproto, struct ofconn *ofconn,
-                 const struct ofp_header *request, uint32_t buffer_id)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    struct ofopgroup *group = ofopgroup_create_unattached(ofproto);
-    if (ofconn) {
-        size_t request_len = ntohs(request->length);
-
-        ovs_assert(ofconn_get_ofproto(ofconn) == ofproto);
-
-        ofconn_add_opgroup(ofconn, &group->ofconn_node);
-        group->ofconn = ofconn;
-        group->request = xmemdup(request, MIN(request_len, 64));
-        group->buffer_id = buffer_id;
-    }
-    return group;
-}
-
-/* Submits 'group' for processing.
- *
- * If 'group' contains no operations (e.g. none were ever added, or all of the
- * ones that were added completed synchronously), then it is destroyed
- * immediately.  Otherwise it is added to the ofproto's list of pending
- * groups. */
-static void
-ofopgroup_submit(struct ofopgroup *group)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    if (!group->n_running) {
-        ofopgroup_complete(group);
-    } else {
-        list_push_back(&group->ofproto->pending, &group->ofproto_node);
-        group->ofproto->n_pending++;
-    }
-}
-
-static void
-ofopgroup_complete(struct ofopgroup *group)
+static enum ofperr
+send_buffered_packet(struct ofconn *ofconn, uint32_t buffer_id,
+                     struct rule *rule)
     OVS_REQUIRES(ofproto_mutex)
 {
-    struct ofproto *ofproto = group->ofproto;
-
-    struct ofconn *abbrev_ofconn;
-    ovs_be32 abbrev_xid;
-
-    struct ofoperation *op, *next_op;
-    int error;
-
-    ovs_assert(!group->n_running);
-
-    error = 0;
-    LIST_FOR_EACH (op, group_node, &group->ops) {
-        if (op->error) {
-            error = op->error;
-            break;
-        }
-    }
-
-    if (!error && group->ofconn && group->buffer_id != UINT32_MAX) {
-        LIST_FOR_EACH (op, group_node, &group->ops) {
-            if (op->type != OFOPERATION_DELETE) {
-                struct ofpbuf *packet;
-                ofp_port_t in_port;
-
-                error = ofconn_pktbuf_retrieve(group->ofconn, group->buffer_id,
-                                               &packet, &in_port);
-                if (packet) {
-                    struct rule_execute *re;
-
-                    ovs_assert(!error);
-
-                    ofproto_rule_ref(op->rule);
-
-                    re = xmalloc(sizeof *re);
-                    re->rule = op->rule;
-                    re->in_port = in_port;
-                    re->packet = packet;
-
-                    if (!guarded_list_push_back(&ofproto->rule_executes,
-                                                &re->list_node, 1024)) {
-                        ofproto_rule_unref(op->rule);
-                        ofpbuf_delete(re->packet);
-                        free(re);
-                    }
-                }
-                break;
-            }
-        }
-    }
-
-    if (!error && !list_is_empty(&group->ofconn_node)) {
-        abbrev_ofconn = group->ofconn;
-        abbrev_xid = group->request->xid;
-    } else {
-        abbrev_ofconn = NULL;
-        abbrev_xid = htonl(0);
-    }
-    LIST_FOR_EACH_SAFE (op, next_op, group_node, &group->ops) {
-        struct rule *rule = op->rule;
-
-        /* We generally want to report the change to active OpenFlow flow
-           monitors (e.g. NXST_FLOW_MONITOR).  There are three exceptions:
+    enum ofperr error = 0;
+    if (ofconn && buffer_id != UINT32_MAX) {
+        struct ofproto *ofproto = ofconn_get_ofproto(ofconn);
+        struct ofpbuf *packet;
+        ofp_port_t in_port;
 
-              - The operation failed.
+        error = ofconn_pktbuf_retrieve(ofconn, buffer_id, &packet, &in_port);
+        if (packet) {
+            struct rule_execute *re;
 
-              - The affected rule is not visible to controllers.
+            ofproto_rule_ref(rule);
 
-              - The operation's only effect was to update rule->modified. */
-        if (!(op->error
-              || ofproto_rule_is_hidden(rule)
-              || (op->type == OFOPERATION_MODIFY
-                  && op->actions
-                  && rule->flow_cookie == op->flow_cookie))) {
-            /* Check that we can just cast from ofoperation_type to
-             * nx_flow_update_event. */
-            enum nx_flow_update_event event_type;
+            re = xmalloc(sizeof *re);
+            re->rule = rule;
+            re->in_port = in_port;
+            re->packet = packet;
 
-            switch (op->type) {
-            case OFOPERATION_ADD:
-            case OFOPERATION_REPLACE:
-                event_type = NXFME_ADDED;
-                break;
-
-            case OFOPERATION_DELETE:
-                event_type = NXFME_DELETED;
-                break;
-
-            case OFOPERATION_MODIFY:
-                event_type = NXFME_MODIFIED;
-                break;
-
-            default:
-                OVS_NOT_REACHED();
-            }
-
-            ofmonitor_report(ofproto->connmgr, rule, event_type,
-                             op->reason, abbrev_ofconn, abbrev_xid);
-        }
-
-        rule->pending = NULL;
-
-        switch (op->type) {
-        case OFOPERATION_ADD:
-            if (!op->error) {
-                uint16_t vid_mask;
-
-                vid_mask = minimask_get_vid_mask(&rule->cr.match.mask);
-                if (vid_mask == VLAN_VID_MASK) {
-                    if (ofproto->vlan_bitmap) {
-                        uint16_t vid = miniflow_get_vid(&rule->cr.match.flow);
-                        if (!bitmap_is_set(ofproto->vlan_bitmap, vid)) {
-                            bitmap_set1(ofproto->vlan_bitmap, vid);
-                            ofproto->vlans_changed = true;
-                        }
-                    } else {
-                        ofproto->vlans_changed = true;
-                    }
-                }
-            } else {
-                oftable_remove_rule(rule);
+            if (!guarded_list_push_back(&ofproto->rule_executes,
+                                        &re->list_node, 1024)) {
                 ofproto_rule_unref(rule);
+                ofpbuf_delete(re->packet);
+                free(re);
             }
-            break;
-
-        case OFOPERATION_DELETE:
-            ovs_assert(!op->error);
-            ofproto_rule_unref(rule);
-            op->rule = NULL;
-            break;
-
-        case OFOPERATION_MODIFY:
-        case OFOPERATION_REPLACE:
-            if (!op->error) {
-                long long int now = time_msec();
-
-                ovs_mutex_lock(&rule->mutex);
-                rule->modified = now;
-                if (op->type == OFOPERATION_REPLACE) {
-                    rule->created = now;
-                }
-                ovs_mutex_unlock(&rule->mutex);
-            } else {
-                ofproto_rule_change_cookie(ofproto, rule, op->flow_cookie);
-                ovs_mutex_lock(&rule->mutex);
-                rule->idle_timeout = op->idle_timeout;
-                rule->hard_timeout = op->hard_timeout;
-                ovs_mutex_unlock(&rule->mutex);
-                if (op->actions) {
-                    struct rule_actions *old_actions;
-
-                    ovs_mutex_lock(&rule->mutex);
-                    old_actions = rule_get_actions(rule);
-                    ovsrcu_set(&rule->actions, op->actions);
-                    ovs_mutex_unlock(&rule->mutex);
-
-                    op->actions = NULL;
-                    rule_actions_destroy(old_actions);
-                }
-                rule->flags = op->flags;
-            }
-            break;
-
-        default:
-            OVS_NOT_REACHED();
         }
-
-        ofoperation_destroy(op);
-    }
-
-    ofmonitor_flush(ofproto->connmgr);
-
-    if (!list_is_empty(&group->ofproto_node)) {
-        ovs_assert(ofproto->n_pending > 0);
-        ofproto->n_pending--;
-        list_remove(&group->ofproto_node);
-    }
-    if (!list_is_empty(&group->ofconn_node)) {
-        list_remove(&group->ofconn_node);
-        if (error) {
-            ofconn_send_error(group->ofconn, group->request, error);
-        }
-        connmgr_retry(ofproto->connmgr);
-    }
-    free(group->request);
-    free(group);
-}
-
-/* Initiates a new operation on 'rule', of the specified 'type', within
- * 'group'.  Prior to calling, 'rule' must not have any pending operation.
- *
- * For a 'type' of OFOPERATION_DELETE, 'reason' should specify the reason that
- * the flow is being deleted.  For other 'type's, 'reason' is ignored (use 0).
- *
- * Returns the newly created ofoperation (which is also available as
- * rule->pending). */
-static struct ofoperation *
-ofoperation_create(struct ofopgroup *group, struct rule *rule,
-                   enum ofoperation_type type,
-                   enum ofp_flow_removed_reason reason)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    struct ofproto *ofproto = group->ofproto;
-    struct ofoperation *op;
-
-    ovs_assert(!rule->pending);
-
-    op = rule->pending = xzalloc(sizeof *op);
-    op->group = group;
-    list_push_back(&group->ops, &op->group_node);
-    op->rule = rule;
-    op->type = type;
-    op->reason = reason;
-    op->flow_cookie = rule->flow_cookie;
-    ovs_mutex_lock(&rule->mutex);
-    op->idle_timeout = rule->idle_timeout;
-    op->hard_timeout = rule->hard_timeout;
-    ovs_mutex_unlock(&rule->mutex);
-    op->flags = rule->flags;
-
-    group->n_running++;
-
-    if (type == OFOPERATION_DELETE) {
-        hmap_insert(&ofproto->deletions, &op->hmap_node,
-                    cls_rule_hash(&rule->cr, rule->table_id));
-    }
-
-    return op;
-}
-
-static void
-ofoperation_destroy(struct ofoperation *op)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    struct ofopgroup *group = op->group;
-
-    if (op->rule) {
-        op->rule->pending = NULL;
-    }
-    if (op->type == OFOPERATION_DELETE) {
-        hmap_remove(&group->ofproto->deletions, &op->hmap_node);
-    }
-    list_remove(&op->group_node);
-    rule_actions_destroy(op->actions);
-    free(op);
-}
-
-/* Indicates that 'op' completed with status 'error', which is either 0 to
- * indicate success or an OpenFlow error code on failure.
- *
- * If 'error' is 0, indicating success, the operation will be committed
- * permanently to the flow table.
- *
- * If 'error' is nonzero, then generally the operation will be rolled back:
- *
- *   - If 'op' is an "add flow" operation, ofproto removes the new rule or
- *     restores the original rule.  The caller must have uninitialized any
- *     derived state in the new rule, as in step 5 of in the "Life Cycle" in
- *     ofproto/ofproto-provider.h.  ofoperation_complete() performs steps 6 and
- *     and 7 for the new rule, calling its ->rule_dealloc() function.
- *
- *   - If 'op' is a "modify flow" operation, ofproto restores the original
- *     actions.
- *
- *   - 'op' must not be a "delete flow" operation.  Removing a rule is not
- *     allowed to fail.  It must always succeed.
- *
- * Please see the large comment in ofproto/ofproto-provider.h titled
- * "Asynchronous Operation Support" for more information. */
-void
-ofoperation_complete(struct ofoperation *op, enum ofperr error)
-{
-    struct ofopgroup *group = op->group;
-
-    ovs_assert(group->n_running > 0);
-    ovs_assert(!error || op->type != OFOPERATION_DELETE);
-
-    op->error = error;
-    if (!--group->n_running && !list_is_empty(&group->ofproto_node)) {
-        /* This function can be called from ->rule_construct(), in which case
-         * ofproto_mutex is held, or it can be called from ->run(), in which
-         * case ofproto_mutex is not held.  But only in the latter case can we
-         * arrive here, so we can safely take ofproto_mutex now. */
-        ovs_mutex_lock(&ofproto_mutex);
-        ovs_assert(op->rule->pending == op);
-        ofopgroup_complete(group);
-        ovs_mutex_unlock(&ofproto_mutex);
     }
+    return error;
 }
 \f
 static uint64_t
@@ -6552,24 +6108,6 @@ choose_rule_to_evict(struct oftable *table, struct rule **rulep)
 
     return false;
 }
-
-/* Searches 'ofproto' for tables that have more flows than their configured
- * maximum and that have flow eviction enabled, and evicts as many flows as
- * necessary and currently feasible from them.
- *
- * This triggers only when an OpenFlow table has N flows in it and then the
- * client configures a maximum number of flows less than N. */
-static void
-ofproto_evict(struct ofproto *ofproto)
-{
-    struct oftable *table;
-
-    ovs_mutex_lock(&ofproto_mutex);
-    OFPROTO_FOR_EACH_TABLE (table, ofproto) {
-        evict_rules_from_table(ofproto, table, 0);
-    }
-    ovs_mutex_unlock(&ofproto_mutex);
-}
 \f
 /* Eviction groups. */
 
@@ -6780,6 +6318,14 @@ oftable_init(struct oftable *table)
     classifier_init(&table->cls, flow_segment_u32s);
     table->max_flows = UINT_MAX;
     atomic_init(&table->config, (unsigned int)OFPROTO_TABLE_MISS_DEFAULT);
+
+    fat_rwlock_wrlock(&table->cls.rwlock);
+    classifier_set_prefix_fields(&table->cls, default_prefix_fields,
+                                 ARRAY_SIZE(default_prefix_fields));
+    fat_rwlock_unlock(&table->cls.rwlock);
+
+    atomic_init(&table->n_matched, 0);
+    atomic_init(&table->n_missed, 0);
 }
 
 /* Destroys 'table', including its classifier and eviction groups.
@@ -6909,40 +6455,6 @@ oftable_remove_rule(struct rule *rule)
 {
     oftable_remove_rule__(rule->ofproto, rule);
 }
-
-/* Inserts 'rule' into its oftable, which must not already contain any rule for
- * the same cls_rule. */
-static void
-oftable_insert_rule(struct rule *rule)
-    OVS_REQUIRES(ofproto_mutex)
-{
-    struct ofproto *ofproto = rule->ofproto;
-    struct oftable *table = &ofproto->tables[rule->table_id];
-    struct rule_actions *actions;
-    bool may_expire;
-
-    ovs_mutex_lock(&rule->mutex);
-    may_expire = rule->hard_timeout || rule->idle_timeout;
-    ovs_mutex_unlock(&rule->mutex);
-
-    if (may_expire) {
-        list_insert(&ofproto->expirable, &rule->expirable);
-    }
-
-    cookies_insert(ofproto, rule);
-
-    actions = rule_get_actions(rule);
-    if (actions->provider_meter_id != UINT32_MAX) {
-        uint32_t meter_id = ofpacts_get_meter(actions->ofpacts,
-                                              actions->ofpacts_len);
-        struct meter *meter = ofproto->meters[meter_id];
-        list_insert(&meter->rules, &rule->meter_list_node);
-    }
-    fat_rwlock_wrlock(&table->cls.rwlock);
-    classifier_insert(&table->cls, CONST_CAST(struct cls_rule *, &rule->cr));
-    fat_rwlock_unlock(&table->cls.rwlock);
-    eviction_group_add_rule(rule);
-}
 \f
 /* unixctl commands. */
 
@@ -7000,29 +6512,36 @@ ofproto_unixctl_init(void)
 void
 ofproto_get_vlan_usage(struct ofproto *ofproto, unsigned long int *vlan_bitmap)
 {
+    struct match match;
+    struct cls_rule target;
     const struct oftable *oftable;
 
+    match_init_catchall(&match);
+    match_set_vlan_vid_masked(&match, htons(VLAN_CFI), htons(VLAN_CFI));
+    cls_rule_init(&target, &match, 0);
+
     free(ofproto->vlan_bitmap);
     ofproto->vlan_bitmap = bitmap_allocate(4096);
     ofproto->vlans_changed = false;
 
     OFPROTO_FOR_EACH_TABLE (oftable, ofproto) {
-        const struct cls_subtable *table;
+        struct cls_cursor cursor;
+        struct rule *rule;
 
         fat_rwlock_rdlock(&oftable->cls.rwlock);
-        HMAP_FOR_EACH (table, hmap_node, &oftable->cls.subtables) {
-            if (minimask_get_vid_mask(&table->mask) == VLAN_VID_MASK) {
-                const struct cls_rule *rule;
-
-                HMAP_FOR_EACH (rule, hmap_node, &table->rules) {
-                    uint16_t vid = miniflow_get_vid(&rule->match.flow);
-                    bitmap_set1(vlan_bitmap, vid);
-                    bitmap_set1(ofproto->vlan_bitmap, vid);
-                }
+        cls_cursor_init(&cursor, &oftable->cls, &target);
+        CLS_CURSOR_FOR_EACH (rule, cr, &cursor) {
+            if (minimask_get_vid_mask(&rule->cr.match.mask) == VLAN_VID_MASK) {
+                uint16_t vid = miniflow_get_vid(&rule->cr.match.flow);
+
+                bitmap_set1(vlan_bitmap, vid);
+                bitmap_set1(ofproto->vlan_bitmap, vid);
             }
         }
         fat_rwlock_unlock(&oftable->cls.rwlock);
     }
+
+    cls_rule_destroy(&target);
 }
 
 /* Returns true if new VLANs have come into use by the flow table since the