2 * Copyright (c) 2014, 2015 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.
17 #ifndef CLASSIFIER_PRIVATE_H
18 #define CLASSIFIER_PRIVATE_H 1
26 /* Classifier internal definitions, subject to change at any time. */
28 /* A set of rules that all have the same fields wildcarded. */
30 struct cmap_node cmap_node; /* Within classifier's 'subtables_map'. */
32 /* These fields are only used by writers. */
33 int max_priority; /* Max priority of any rule in subtable. */
34 unsigned int max_count; /* Count of max_priority rules. */
36 /* Accessed by iterators. */
37 struct rculist rules_list; /* Unordered. */
39 /* Identical, but lower priority rules are not inserted to any of the
40 * following data structures. */
42 /* These fields are accessed by readers who care about wildcarding. */
43 const tag_type tag; /* Tag generated from mask for partitioning. */
44 const uint8_t n_indices; /* How many indices to use. */
45 const struct flowmap index_maps[CLS_MAX_INDICES + 1]; /* Stage maps. */
46 unsigned int trie_plen[CLS_MAX_TRIES]; /* Trie prefix length in 'mask'
47 * (runtime configurable). */
48 const int ports_mask_len;
49 struct cmap indices[CLS_MAX_INDICES]; /* Staged lookup indices. */
50 rcu_trie_ptr ports_trie; /* NULL if none. */
52 /* These fields are accessed by all readers. */
53 struct cmap rules; /* Contains 'cls_match'es. */
54 const struct minimask mask; /* Wildcards for fields. */
55 /* 'mask' must be the last field. */
58 /* Associates a metadata value (that is, a value of the OpenFlow 1.1+ metadata
59 * field) with tags for the "cls_subtable"s that contain rules that match that
61 struct cls_partition {
62 struct cmap_node cmap_node; /* In struct classifier's 'partitions' map. */
63 ovs_be64 metadata; /* metadata value for this partition. */
64 tag_type tags; /* OR of each flow's cls_subtable tag. */
65 struct tag_tracker tracker; /* Tracks the bits in 'tags'. */
68 /* Internal representation of a rule in a "struct cls_subtable".
70 * The 'next' member is an element in a singly linked, null-terminated list.
71 * This list links together identical "cls_match"es in order of decreasing
72 * priority. The classifier code maintains the invariant that at most one rule
73 * of a given priority is visible for any given lookup version.
76 /* Accessed by everybody. */
77 OVSRCU_TYPE(struct cls_match *) next; /* Equal, lower-priority matches. */
78 OVSRCU_TYPE(struct cls_conjunction_set *) conj_set;
80 /* Accessed only by writers. */
81 struct cls_partition *partition;
83 /* Accessed by readers interested in wildcarding. */
84 const int priority; /* Larger numbers are higher priorities. */
85 struct cmap_node index_nodes[CLS_MAX_INDICES]; /* Within subtable's
87 /* Accessed by all readers. */
88 struct cmap_node cmap_node; /* Within struct cls_subtable 'rules'. */
92 * CLS_NOT_REMOVED_VERSION has a special meaning for 'remove_version',
93 * meaningthat the rule has been added but not yet removed.
95 const cls_version_t add_version; /* Version rule was added in. */
96 ATOMIC(cls_version_t) remove_version; /* Version rule is removed in. */
98 const struct cls_rule *cls_rule;
99 const struct miniflow flow; /* Matching rule. Mask is in the subtable. */
100 /* 'flow' must be the last field. */
103 /* Must be RCU postponed. */
104 void cls_match_free_cb(struct cls_match *);
107 cls_match_set_remove_version(struct cls_match *rule, cls_version_t version)
109 atomic_store_relaxed(&rule->remove_version, version);
113 cls_match_visible_in_version(const struct cls_match *rule,
114 cls_version_t version)
116 cls_version_t remove_version;
118 /* C11 does not want to access an atomic via a const object pointer. */
119 atomic_read_relaxed(&CONST_CAST(struct cls_match *, rule)->remove_version,
122 return rule->add_version <= version && version < remove_version;
126 cls_match_is_eventually_invisible(const struct cls_match *rule)
128 cls_version_t remove_version;
130 /* C11 does not want to access an atomic via a const object pointer. */
131 atomic_read_relaxed(&CONST_CAST(struct cls_match *, rule)->remove_version,
134 return remove_version <= CLS_MAX_VERSION;
138 /* cls_match 'next' */
140 static inline const struct cls_match *
141 cls_match_next(const struct cls_match *rule)
143 return ovsrcu_get(struct cls_match *, &rule->next);
146 static inline struct cls_match *
147 cls_match_next_protected(const struct cls_match *rule)
149 return ovsrcu_get_protected(struct cls_match *, &rule->next);
152 /* Puts 'rule' in the position between 'prev' and 'next'. If 'prev' == NULL,
153 * then the 'rule' is the new list head, and if 'next' == NULL, the rule is the
155 * If there are any nodes between 'prev' and 'next', they are dropped from the
158 cls_match_insert(struct cls_match *prev, struct cls_match *next,
159 struct cls_match *rule)
161 ovsrcu_set_hidden(&rule->next, next);
164 ovsrcu_set(&prev->next, rule);
168 /* Puts 'new_rule' in the position of 'old_rule', which is the next node after
169 * 'prev'. If 'prev' == NULL, then the 'new_rule' is the new list head.
171 * The replaced cls_match still links to the later rules, and may still be
172 * referenced by other threads until all other threads quiesce. The replaced
173 * rule may not be re-inserted, re-initialized, or deleted until after all
174 * other threads have quiesced (use ovsrcu_postpone). */
176 cls_match_replace(struct cls_match *prev,
177 struct cls_match *old_rule, struct cls_match *new_rule)
179 cls_match_insert(prev, cls_match_next_protected(old_rule), new_rule);
182 /* Removes 'rule' following 'prev' from the list. If 'prev' is NULL, then the
183 * 'rule' is a list head, and the caller is responsible for maintaining its
184 * list head pointer (if any).
186 * Afterward, the removed rule is not linked to any more, but still links to
187 * the following rules, and may still be referenced by other threads until all
188 * other threads quiesce. The removed rule may not be re-inserted,
189 * re-initialized, or deleted until after all other threads have quiesced (use
193 cls_match_remove(struct cls_match *prev, struct cls_match *rule)
196 ovsrcu_set(&prev->next, cls_match_next_protected(rule));
200 #define CLS_MATCH_FOR_EACH(ITER, HEAD) \
201 for ((ITER) = (HEAD); (ITER); (ITER) = cls_match_next(ITER))
203 #define CLS_MATCH_FOR_EACH_AFTER_HEAD(ITER, HEAD) \
204 CLS_MATCH_FOR_EACH(ITER, cls_match_next(HEAD))
206 /* Iterate cls_matches keeping the previous pointer for modifications. */
207 #define FOR_EACH_RULE_IN_LIST_PROTECTED(ITER, PREV, HEAD) \
208 for ((PREV) = NULL, (ITER) = (HEAD); \
210 (PREV) = (ITER), (ITER) = cls_match_next_protected(ITER))
213 /* A longest-prefix match tree. */
215 uint32_t prefix; /* Prefix bits for this node, MSB first. */
216 uint8_t n_bits; /* Never zero, except for the root node. */
217 unsigned int n_rules; /* Number of rules that have this prefix. */
218 rcu_trie_ptr edges[2]; /* Both NULL if leaf. */
221 /* Max bits per node. Must fit in struct trie_node's 'prefix'.
222 * Also tested with 16, 8, and 5 to stress the implementation. */
223 #define TRIE_PREFIX_BITS 32
225 /* flow/miniflow/minimask/minimatch utilities.
226 * These are only used by the classifier, so place them here to allow
227 * for better optimization. */
229 /* Returns a hash value for the bits of 'flow' where there are 1-bits in
230 * 'mask', given 'basis'.
232 * The hash values returned by this function are the same as those returned by
233 * miniflow_hash_in_minimask(), only the form of the arguments differ. */
234 static inline uint32_t
235 flow_hash_in_minimask(const struct flow *flow, const struct minimask *mask,
238 const uint64_t *mask_values = miniflow_get_values(&mask->masks);
239 const uint64_t *flow_u64 = (const uint64_t *)flow;
240 const uint64_t *p = mask_values;
241 uint32_t hash = basis;
244 FLOWMAP_FOR_EACH_MAP (map, mask->masks.map) {
247 MAP_FOR_EACH_INDEX (idx, map) {
248 hash = hash_add64(hash, flow_u64[idx] & *p++);
250 flow_u64 += MAP_T_BITS;
253 return hash_finish(hash, (p - mask_values) * 8);
256 /* Returns a hash value for the bits of 'flow' where there are 1-bits in
257 * 'mask', given 'basis'.
259 * The hash values returned by this function are the same as those returned by
260 * flow_hash_in_minimask(), only the form of the arguments differ. */
261 static inline uint32_t
262 miniflow_hash_in_minimask(const struct miniflow *flow,
263 const struct minimask *mask, uint32_t basis)
265 const uint64_t *mask_values = miniflow_get_values(&mask->masks);
266 const uint64_t *p = mask_values;
267 uint32_t hash = basis;
270 MINIFLOW_FOR_EACH_IN_FLOWMAP(value, flow, mask->masks.map) {
271 hash = hash_add64(hash, value & *p++);
274 return hash_finish(hash, (p - mask_values) * 8);
277 /* Returns a hash value for the values of 'flow', indicated by 'range', where
278 * there are 1-bits in 'mask', given 'basis'. 'range' must be a continuous
279 * subset of the bits in 'mask''s map, representing a continuous range of the
280 * minimask's mask data. '*offset' must be the number of 64-bit units of the
281 * minimask's data to skip to get to the first unit covered by 'range'. On
282 * return '*offset' is updated with the number of 64-bit units of the minimask
285 * Typically this function is called for successive ranges of minimask's masks,
286 * and the first invocation passes '*offset' as zero.
288 * The hash values returned by this function are the same as those returned by
289 * minimatch_hash_range(), only the form of the arguments differ. */
290 static inline uint32_t
291 flow_hash_in_minimask_range(const struct flow *flow,
292 const struct minimask *mask,
293 const struct flowmap range,
294 unsigned int *offset,
297 const uint64_t *mask_values = miniflow_get_values(&mask->masks);
298 const uint64_t *flow_u64 = (const uint64_t *)flow;
299 const uint64_t *p = mask_values + *offset;
300 uint32_t hash = *basis;
303 FLOWMAP_FOR_EACH_MAP (map, range) {
306 MAP_FOR_EACH_INDEX (idx, map) {
307 hash = hash_add64(hash, flow_u64[idx] & *p++);
309 flow_u64 += MAP_T_BITS;
312 *basis = hash; /* Allow continuation from the unfinished value. */
313 *offset = p - mask_values;
314 return hash_finish(hash, *offset * 8);
317 /* Fold minimask 'mask''s wildcard mask into 'wc's wildcard mask. */
319 flow_wildcards_fold_minimask(struct flow_wildcards *wc,
320 const struct minimask *mask)
322 flow_union_with_miniflow(&wc->masks, &mask->masks);
325 /* Fold minimask 'mask''s wildcard mask into 'wc's wildcard mask for bits in
326 * 'fmap'. 1-bits in 'fmap' are a subset of 1-bits in 'mask''s map. */
328 flow_wildcards_fold_minimask_in_map(struct flow_wildcards *wc,
329 const struct minimask *mask,
330 const struct flowmap fmap)
332 flow_union_with_miniflow_subset(&wc->masks, &mask->masks, fmap);
335 /* Returns a hash value for 'mask', given 'basis'. */
336 static inline uint32_t
337 minimask_hash(const struct minimask *mask, uint32_t basis)
339 const uint64_t *p = miniflow_get_values(&mask->masks);
340 size_t n_values = miniflow_n_values(&mask->masks);
341 uint32_t hash = basis;
343 for (size_t i = 0; i < n_values; i++) {
344 hash = hash_add64(hash, *p++);
348 FLOWMAP_FOR_EACH_MAP (map, mask->masks.map) {
349 hash = hash_add64(hash, map);
352 return hash_finish(hash, n_values);
355 /* Returns a hash value for the values of 'match->flow', indicated by 'range',
356 * where there are 1-bits in 'match->mask', given 'basis'. 'range' must be a
357 * continuous subset of the bits in the map of 'match', representing a
358 * continuous range of the mask data of 'match'. '*offset' must be the number
359 * of 64-bit units of the match data to skip to get to the first unit covered
360 * by 'range'. On return '*offset' is updated with the number of 64-bit units
361 * of the match consumed.
363 * Typically this function is called for successive ranges of minimask's masks,
364 * and the first invocation passes '*offset' as zero.
366 * The hash values returned by this function are the same as those returned by
367 * flow_hash_in_minimask_range(), only the form of the arguments differ. */
368 static inline uint32_t
369 minimatch_hash_range(const struct minimatch *match,
370 const struct flowmap range, unsigned int *offset,
373 const uint64_t *p = miniflow_get_values(match->flow) + *offset;
374 const uint64_t *q = miniflow_get_values(&match->mask->masks) + *offset;
375 unsigned int n = flowmap_n_1bits(range);
376 uint32_t hash = *basis;
378 for (unsigned int i = 0; i < n; i++) {
379 hash = hash_add64(hash, p[i] & q[i]);
381 *basis = hash; /* Allow continuation from the unfinished value. */
383 return hash_finish(hash, *offset * 8);