2 * Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 #define CLASSIFIER_H 1
22 * A classifier is a "struct classifier",
23 * a hash map from a set of wildcards to a "struct cls_table",
24 * a hash map from fixed field values to "struct cls_rule",
25 * which can contain a list of otherwise identical rules
26 * with lower priorities.
31 * When locked properly, the classifier is thread safe as long as the following
32 * conditions are satisfied.
33 * - Only the main thread calls functions requiring a write lock.
34 * - Only the main thread is allowed to iterate over rules. */
40 #include "openflow/nicira-ext.h"
41 #include "openflow/openflow.h"
42 #include "ovs-thread.h"
49 /* A flow classifier. */
51 int n_rules; /* Total number of rules. */
52 struct hmap tables; /* Contains "struct cls_table"s. */
53 struct list tables_priority; /* Tables in descending priority order */
54 struct ovs_rwlock rwlock;
57 /* A set of rules that all have the same fields wildcarded. */
59 struct hmap_node hmap_node; /* Within struct classifier 'tables' hmap. */
60 struct list list_node; /* Within classifier 'tables_priority_list' */
61 struct hmap rules; /* Contains "struct cls_rule"s. */
62 struct minimask mask; /* Wildcards for fields. */
63 int n_table_rules; /* Number of rules, including duplicates. */
64 unsigned int max_priority; /* Max priority of any rule in the table. */
65 unsigned int max_count; /* Count of max_priority rules. */
68 /* Returns true if 'table' is a "catch-all" table that will match every
69 * packet (if there is no higher-priority match). */
71 cls_table_is_catchall(const struct cls_table *table)
73 return minimask_is_catchall(&table->mask);
76 /* A rule in a "struct classifier". */
78 struct hmap_node hmap_node; /* Within struct cls_table 'rules'. */
79 struct list list; /* List of identical, lower-priority rules. */
80 struct minimatch match; /* Matching rule. */
81 unsigned int priority; /* Larger numbers are higher priorities. */
84 void cls_rule_init(struct cls_rule *, const struct match *,
85 unsigned int priority);
86 void cls_rule_init_from_minimatch(struct cls_rule *, const struct minimatch *,
87 unsigned int priority);
88 void cls_rule_clone(struct cls_rule *, const struct cls_rule *);
89 void cls_rule_destroy(struct cls_rule *);
91 bool cls_rule_equal(const struct cls_rule *, const struct cls_rule *);
92 uint32_t cls_rule_hash(const struct cls_rule *, uint32_t basis);
94 void cls_rule_format(const struct cls_rule *, struct ds *);
96 bool cls_rule_is_catchall(const struct cls_rule *);
98 bool cls_rule_is_loose_match(const struct cls_rule *rule,
99 const struct minimatch *criteria);
101 void classifier_init(struct classifier *cls);
102 void classifier_destroy(struct classifier *);
103 bool classifier_is_empty(const struct classifier *cls)
104 OVS_REQ_RDLOCK(cls->rwlock);
105 int classifier_count(const struct classifier *cls)
106 OVS_REQ_RDLOCK(cls->rwlock);
107 void classifier_insert(struct classifier *cls, struct cls_rule *)
108 OVS_REQ_WRLOCK(cls->rwlock);
109 struct cls_rule *classifier_replace(struct classifier *cls, struct cls_rule *)
110 OVS_REQ_WRLOCK(cls->rwlock);
111 void classifier_remove(struct classifier *cls, struct cls_rule *)
112 OVS_REQ_WRLOCK(cls->rwlock);
113 struct cls_rule *classifier_lookup(const struct classifier *cls,
115 struct flow_wildcards *)
116 OVS_REQ_RDLOCK(cls->rwlock);
117 bool classifier_rule_overlaps(const struct classifier *cls,
118 const struct cls_rule *)
119 OVS_REQ_RDLOCK(cls->rwlock);
121 typedef void cls_cb_func(struct cls_rule *, void *aux);
123 struct cls_rule *classifier_find_rule_exactly(const struct classifier *cls,
124 const struct cls_rule *)
125 OVS_REQ_RDLOCK(cls->rwlock);
126 struct cls_rule *classifier_find_match_exactly(const struct classifier *cls,
127 const struct match *,
128 unsigned int priority)
129 OVS_REQ_RDLOCK(cls->rwlock);
134 const struct classifier *cls;
135 const struct cls_table *table;
136 const struct cls_rule *target;
139 void cls_cursor_init(struct cls_cursor *cursor, const struct classifier *cls,
140 const struct cls_rule *match) OVS_REQ_RDLOCK(cls->rwlock);
141 struct cls_rule *cls_cursor_first(struct cls_cursor *cursor);
142 struct cls_rule *cls_cursor_next(struct cls_cursor *cursor, struct cls_rule *);
144 #define CLS_CURSOR_FOR_EACH(RULE, MEMBER, CURSOR) \
145 for (ASSIGN_CONTAINER(RULE, cls_cursor_first(CURSOR), MEMBER); \
146 RULE != OBJECT_CONTAINING(NULL, RULE, MEMBER); \
147 ASSIGN_CONTAINER(RULE, cls_cursor_next(CURSOR, &(RULE)->MEMBER), \
150 #define CLS_CURSOR_FOR_EACH_SAFE(RULE, NEXT, MEMBER, CURSOR) \
151 for (ASSIGN_CONTAINER(RULE, cls_cursor_first(CURSOR), MEMBER); \
152 (RULE != OBJECT_CONTAINING(NULL, RULE, MEMBER) \
153 ? ASSIGN_CONTAINER(NEXT, cls_cursor_next(CURSOR, &(RULE)->MEMBER), \
162 #endif /* classifier.h */