]>
git.proxmox.com Git - ovs.git/blob - lib/classifier.c
2 * Copyright (c) 2009, 2010, 2011, 2012, 2013 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 #include "classifier.h"
20 #include <netinet/in.h>
21 #include "byte-order.h"
22 #include "dynamic-string.h"
28 #include "ovs-thread.h"
30 static struct cls_table
*find_table(const struct classifier
*,
31 const struct minimask
*);
32 static struct cls_table
*insert_table(struct classifier
*,
33 const struct minimask
*);
35 static void destroy_table(struct classifier
*, struct cls_table
*);
37 static void update_tables_after_insertion(struct classifier
*,
39 unsigned int new_priority
);
40 static void update_tables_after_removal(struct classifier
*,
42 unsigned int del_priority
);
44 static struct cls_rule
*find_match(const struct cls_table
*,
46 static struct cls_rule
*find_equal(struct cls_table
*,
47 const struct miniflow
*, uint32_t hash
);
48 static struct cls_rule
*insert_rule(struct classifier
*,
49 struct cls_table
*, struct cls_rule
*);
51 /* Iterates RULE over HEAD and all of the cls_rules on HEAD->list. */
52 #define FOR_EACH_RULE_IN_LIST(RULE, HEAD) \
53 for ((RULE) = (HEAD); (RULE) != NULL; (RULE) = next_rule_in_list(RULE))
54 #define FOR_EACH_RULE_IN_LIST_SAFE(RULE, NEXT, HEAD) \
55 for ((RULE) = (HEAD); \
56 (RULE) != NULL && ((NEXT) = next_rule_in_list(RULE), true); \
59 static struct cls_rule
*next_rule_in_list__(struct cls_rule
*);
60 static struct cls_rule
*next_rule_in_list(struct cls_rule
*);
64 /* Initializes 'rule' to match packets specified by 'match' at the given
65 * 'priority'. 'match' must satisfy the invariant described in the comment at
66 * the definition of struct match.
68 * The caller must eventually destroy 'rule' with cls_rule_destroy().
70 * (OpenFlow uses priorities between 0 and UINT16_MAX, inclusive, but
71 * internally Open vSwitch supports a wider range.) */
73 cls_rule_init(struct cls_rule
*rule
,
74 const struct match
*match
, unsigned int priority
)
76 minimatch_init(&rule
->match
, match
);
77 rule
->priority
= priority
;
80 /* Same as cls_rule_init() for initialization from a "struct minimatch". */
82 cls_rule_init_from_minimatch(struct cls_rule
*rule
,
83 const struct minimatch
*match
,
84 unsigned int priority
)
86 minimatch_clone(&rule
->match
, match
);
87 rule
->priority
= priority
;
90 /* Initializes 'dst' as a copy of 'src'.
92 * The caller must eventually destroy 'dst' with cls_rule_destroy(). */
94 cls_rule_clone(struct cls_rule
*dst
, const struct cls_rule
*src
)
96 minimatch_clone(&dst
->match
, &src
->match
);
97 dst
->priority
= src
->priority
;
100 /* Initializes 'dst' with the data in 'src', destroying 'src'.
102 * The caller must eventually destroy 'dst' with cls_rule_destroy(). */
104 cls_rule_move(struct cls_rule
*dst
, struct cls_rule
*src
)
106 minimatch_move(&dst
->match
, &src
->match
);
107 dst
->priority
= src
->priority
;
110 /* Frees memory referenced by 'rule'. Doesn't free 'rule' itself (it's
111 * normally embedded into a larger structure).
113 * ('rule' must not currently be in a classifier.) */
115 cls_rule_destroy(struct cls_rule
*rule
)
117 minimatch_destroy(&rule
->match
);
120 /* Returns true if 'a' and 'b' match the same packets at the same priority,
121 * false if they differ in some way. */
123 cls_rule_equal(const struct cls_rule
*a
, const struct cls_rule
*b
)
125 return a
->priority
== b
->priority
&& minimatch_equal(&a
->match
, &b
->match
);
128 /* Returns a hash value for 'rule', folding in 'basis'. */
130 cls_rule_hash(const struct cls_rule
*rule
, uint32_t basis
)
132 return minimatch_hash(&rule
->match
, hash_int(rule
->priority
, basis
));
135 /* Appends a string describing 'rule' to 's'. */
137 cls_rule_format(const struct cls_rule
*rule
, struct ds
*s
)
139 minimatch_format(&rule
->match
, s
, rule
->priority
);
142 /* Returns true if 'rule' matches every packet, false otherwise. */
144 cls_rule_is_catchall(const struct cls_rule
*rule
)
146 return minimask_is_catchall(&rule
->match
.mask
);
149 /* Initializes 'cls' as a classifier that initially contains no classification
152 classifier_init(struct classifier
*cls
)
155 hmap_init(&cls
->tables
);
156 list_init(&cls
->tables_priority
);
157 hmap_init(&cls
->partitions
);
158 ovs_rwlock_init(&cls
->rwlock
);
161 /* Destroys 'cls'. Rules within 'cls', if any, are not freed; this is the
162 * caller's responsibility. */
164 classifier_destroy(struct classifier
*cls
)
167 struct cls_table
*partition
, *next_partition
;
168 struct cls_table
*table
, *next_table
;
170 HMAP_FOR_EACH_SAFE (table
, next_table
, hmap_node
, &cls
->tables
) {
171 destroy_table(cls
, table
);
173 hmap_destroy(&cls
->tables
);
175 HMAP_FOR_EACH_SAFE (partition
, next_partition
, hmap_node
,
177 hmap_remove(&cls
->partitions
, &partition
->hmap_node
);
180 hmap_destroy(&cls
->partitions
);
181 ovs_rwlock_destroy(&cls
->rwlock
);
185 /* Returns true if 'cls' contains no classification rules, false otherwise. */
187 classifier_is_empty(const struct classifier
*cls
)
189 return cls
->n_rules
== 0;
192 /* Returns the number of rules in 'cls'. */
194 classifier_count(const struct classifier
*cls
)
200 hash_metadata(ovs_be64 metadata_
)
202 uint64_t metadata
= (OVS_FORCE
uint64_t) metadata_
;
203 return hash_2words(metadata
, metadata
>> 32);
206 static struct cls_partition
*
207 find_partition(const struct classifier
*cls
, ovs_be64 metadata
, uint32_t hash
)
209 struct cls_partition
*partition
;
211 HMAP_FOR_EACH_IN_BUCKET (partition
, hmap_node
, hash
, &cls
->partitions
) {
212 if (partition
->metadata
== metadata
) {
220 static struct cls_partition
*
221 create_partition(struct classifier
*cls
, struct cls_table
*table
,
224 uint32_t hash
= hash_metadata(metadata
);
225 struct cls_partition
*partition
= find_partition(cls
, metadata
, hash
);
227 partition
= xmalloc(sizeof *partition
);
228 partition
->metadata
= metadata
;
230 partition
->n_refs
= 0;
231 hmap_insert(&cls
->partitions
, &partition
->hmap_node
, hash
);
233 partition
->tags
|= table
->tag
;
238 /* Inserts 'rule' into 'cls'. Until 'rule' is removed from 'cls', the caller
239 * must not modify or free it.
241 * If 'cls' already contains an identical rule (including wildcards, values of
242 * fixed fields, and priority), replaces the old rule by 'rule' and returns the
243 * rule that was replaced. The caller takes ownership of the returned rule and
244 * is thus responsible for destroying it with cls_rule_destroy(), freeing the
245 * memory block in which it resides, etc., as necessary.
247 * Returns NULL if 'cls' does not contain a rule with an identical key, after
248 * inserting the new rule. In this case, no rules are displaced by the new
249 * rule, even rules that cannot have any effect because the new rule matches a
250 * superset of their flows and has higher priority. */
252 classifier_replace(struct classifier
*cls
, struct cls_rule
*rule
)
254 struct cls_rule
*old_rule
;
255 struct cls_table
*table
;
257 table
= find_table(cls
, &rule
->match
.mask
);
259 table
= insert_table(cls
, &rule
->match
.mask
);
262 old_rule
= insert_rule(cls
, table
, rule
);
264 if (minimask_get_metadata_mask(&rule
->match
.mask
) == OVS_BE64_MAX
) {
265 ovs_be64 metadata
= miniflow_get_metadata(&rule
->match
.flow
);
266 rule
->partition
= create_partition(cls
, table
, metadata
);
268 rule
->partition
= NULL
;
271 table
->n_table_rules
++;
274 rule
->partition
= old_rule
->partition
;
279 /* Inserts 'rule' into 'cls'. Until 'rule' is removed from 'cls', the caller
280 * must not modify or free it.
282 * 'cls' must not contain an identical rule (including wildcards, values of
283 * fixed fields, and priority). Use classifier_find_rule_exactly() to find
286 classifier_insert(struct classifier
*cls
, struct cls_rule
*rule
)
288 struct cls_rule
*displaced_rule
= classifier_replace(cls
, rule
);
289 ovs_assert(!displaced_rule
);
292 /* Removes 'rule' from 'cls'. It is the caller's responsibility to destroy
293 * 'rule' with cls_rule_destroy(), freeing the memory block in which 'rule'
294 * resides, etc., as necessary. */
296 classifier_remove(struct classifier
*cls
, struct cls_rule
*rule
)
298 struct cls_partition
*partition
;
299 struct cls_rule
*head
;
300 struct cls_table
*table
;
302 table
= find_table(cls
, &rule
->match
.mask
);
303 head
= find_equal(table
, &rule
->match
.flow
, rule
->hmap_node
.hash
);
305 list_remove(&rule
->list
);
306 } else if (list_is_empty(&rule
->list
)) {
307 hmap_remove(&table
->rules
, &rule
->hmap_node
);
309 struct cls_rule
*next
= CONTAINER_OF(rule
->list
.next
,
310 struct cls_rule
, list
);
312 list_remove(&rule
->list
);
313 hmap_replace(&table
->rules
, &rule
->hmap_node
, &next
->hmap_node
);
316 partition
= rule
->partition
;
317 if (partition
&& --partition
->n_refs
== 0) {
318 hmap_remove(&cls
->partitions
, &partition
->hmap_node
);
322 if (--table
->n_table_rules
== 0) {
323 destroy_table(cls
, table
);
325 update_tables_after_removal(cls
, table
, rule
->priority
);
330 /* Finds and returns the highest-priority rule in 'cls' that matches 'flow'.
331 * Returns a null pointer if no rules in 'cls' match 'flow'. If multiple rules
332 * of equal priority match 'flow', returns one arbitrarily.
334 * If a rule is found and 'wc' is non-null, bitwise-OR's 'wc' with the
335 * set of bits that were significant in the lookup. At some point
336 * earlier, 'wc' should have been initialized (e.g., by
337 * flow_wildcards_init_catchall()). */
339 classifier_lookup(const struct classifier
*cls
, const struct flow
*flow
,
340 struct flow_wildcards
*wc
)
342 const struct cls_partition
*partition
;
343 struct cls_table
*table
;
344 struct cls_rule
*best
;
347 /* Determine 'tags' such that, if 'table->tag' doesn't intersect them, then
348 * 'flow' cannot possibly match in 'table':
350 * - If flow->metadata maps to a given 'partition', then we can use
351 * 'tags' for 'partition->tags'.
353 * - If flow->metadata has no partition, then no rule in 'cls' has an
354 * exact-match for flow->metadata. That means that we don't need to
355 * search any table that includes flow->metadata in its mask.
357 * In either case, we always need to search any cls_tables that do not
358 * include flow->metadata in its mask. One way to do that would be to
359 * check the "cls_table"s explicitly for that, but that would require an
360 * extra branch per table. Instead, we mark such a cls_table's 'tags' as
361 * TAG_ALL and make sure that 'tags' is never empty. This means that
362 * 'tags' always intersects such a cls_table's 'tags', so we don't need a
365 partition
= (hmap_is_empty(&cls
->partitions
)
367 : find_partition(cls
, flow
->metadata
,
368 hash_metadata(flow
->metadata
)));
369 tags
= partition
? partition
->tags
: TAG_ARBITRARY
;
372 LIST_FOR_EACH (table
, list_node
, &cls
->tables_priority
) {
373 struct cls_rule
*rule
;
375 if (!tag_intersects(tags
, table
->tag
)) {
379 rule
= find_match(table
, flow
);
381 flow_wildcards_fold_minimask(wc
, &table
->mask
);
385 LIST_FOR_EACH_CONTINUE (table
, list_node
, &cls
->tables_priority
) {
386 if (table
->max_priority
<= best
->priority
) {
387 /* Tables in descending priority order,
388 * can not find anything better. */
391 if (!tag_intersects(tags
, table
->tag
)) {
395 rule
= find_match(table
, flow
);
397 flow_wildcards_fold_minimask(wc
, &table
->mask
);
399 if (rule
&& rule
->priority
> best
->priority
) {
409 /* Finds and returns a rule in 'cls' with exactly the same priority and
410 * matching criteria as 'target'. Returns a null pointer if 'cls' doesn't
411 * contain an exact match. */
413 classifier_find_rule_exactly(const struct classifier
*cls
,
414 const struct cls_rule
*target
)
416 struct cls_rule
*head
, *rule
;
417 struct cls_table
*table
;
419 table
= find_table(cls
, &target
->match
.mask
);
424 /* Skip if there is no hope. */
425 if (target
->priority
> table
->max_priority
) {
429 head
= find_equal(table
, &target
->match
.flow
,
430 miniflow_hash_in_minimask(&target
->match
.flow
,
431 &target
->match
.mask
, 0));
432 FOR_EACH_RULE_IN_LIST (rule
, head
) {
433 if (target
->priority
>= rule
->priority
) {
434 return target
->priority
== rule
->priority
? rule
: NULL
;
440 /* Finds and returns a rule in 'cls' with priority 'priority' and exactly the
441 * same matching criteria as 'target'. Returns a null pointer if 'cls' doesn't
442 * contain an exact match. */
444 classifier_find_match_exactly(const struct classifier
*cls
,
445 const struct match
*target
,
446 unsigned int priority
)
448 struct cls_rule
*retval
;
451 cls_rule_init(&cr
, target
, priority
);
452 retval
= classifier_find_rule_exactly(cls
, &cr
);
453 cls_rule_destroy(&cr
);
458 /* Checks if 'target' would overlap any other rule in 'cls'. Two rules are
459 * considered to overlap if both rules have the same priority and a packet
460 * could match both. */
462 classifier_rule_overlaps(const struct classifier
*cls
,
463 const struct cls_rule
*target
)
465 struct cls_table
*table
;
467 /* Iterate tables in the descending max priority order. */
468 LIST_FOR_EACH (table
, list_node
, &cls
->tables_priority
) {
469 uint32_t storage
[FLOW_U32S
];
470 struct minimask mask
;
471 struct cls_rule
*head
;
473 if (target
->priority
> table
->max_priority
) {
474 break; /* Can skip this and the rest of the tables. */
477 minimask_combine(&mask
, &target
->match
.mask
, &table
->mask
, storage
);
478 HMAP_FOR_EACH (head
, hmap_node
, &table
->rules
) {
479 struct cls_rule
*rule
;
481 FOR_EACH_RULE_IN_LIST (rule
, head
) {
482 if (rule
->priority
< target
->priority
) {
483 break; /* Rules in descending priority order. */
485 if (rule
->priority
== target
->priority
486 && miniflow_equal_in_minimask(&target
->match
.flow
,
487 &rule
->match
.flow
, &mask
)) {
497 /* Returns true if 'rule' exactly matches 'criteria' or if 'rule' is more
498 * specific than 'criteria'. That is, 'rule' matches 'criteria' and this
499 * function returns true if, for every field:
501 * - 'criteria' and 'rule' specify the same (non-wildcarded) value for the
504 * - 'criteria' wildcards the field,
506 * Conversely, 'rule' does not match 'criteria' and this function returns false
507 * if, for at least one field:
509 * - 'criteria' and 'rule' specify different values for the field, or
511 * - 'criteria' specifies a value for the field but 'rule' wildcards it.
513 * Equivalently, the truth table for whether a field matches is:
518 * r +---------+---------+
519 * i wild | yes | yes |
521 * e +---------+---------+
522 * r exact | no |if values|
524 * a +---------+---------+
526 * This is the matching rule used by OpenFlow 1.0 non-strict OFPT_FLOW_MOD
527 * commands and by OpenFlow 1.0 aggregate and flow stats.
529 * Ignores rule->priority. */
531 cls_rule_is_loose_match(const struct cls_rule
*rule
,
532 const struct minimatch
*criteria
)
534 return (!minimask_has_extra(&rule
->match
.mask
, &criteria
->mask
)
535 && miniflow_equal_in_minimask(&rule
->match
.flow
, &criteria
->flow
,
542 rule_matches(const struct cls_rule
*rule
, const struct cls_rule
*target
)
545 || miniflow_equal_in_minimask(&rule
->match
.flow
,
547 &target
->match
.mask
));
550 static struct cls_rule
*
551 search_table(const struct cls_table
*table
, const struct cls_rule
*target
)
553 if (!target
|| !minimask_has_extra(&table
->mask
, &target
->match
.mask
)) {
554 struct cls_rule
*rule
;
556 HMAP_FOR_EACH (rule
, hmap_node
, &table
->rules
) {
557 if (rule_matches(rule
, target
)) {
565 /* Initializes 'cursor' for iterating through rules in 'cls':
567 * - If 'target' is null, the cursor will visit every rule in 'cls'.
569 * - If 'target' is nonnull, the cursor will visit each 'rule' in 'cls'
570 * such that cls_rule_is_loose_match(rule, target) returns true.
572 * Ignores target->priority. */
574 cls_cursor_init(struct cls_cursor
*cursor
, const struct classifier
*cls
,
575 const struct cls_rule
*target
)
578 cursor
->target
= target
&& !cls_rule_is_catchall(target
) ? target
: NULL
;
581 /* Returns the first matching cls_rule in 'cursor''s iteration, or a null
582 * pointer if there are no matches. */
584 cls_cursor_first(struct cls_cursor
*cursor
)
586 struct cls_table
*table
;
588 HMAP_FOR_EACH (table
, hmap_node
, &cursor
->cls
->tables
) {
589 struct cls_rule
*rule
= search_table(table
, cursor
->target
);
591 cursor
->table
= table
;
599 /* Returns the next matching cls_rule in 'cursor''s iteration, or a null
600 * pointer if there are no more matches. */
602 cls_cursor_next(struct cls_cursor
*cursor
, const struct cls_rule
*rule_
)
604 struct cls_rule
*rule
= CONST_CAST(struct cls_rule
*, rule_
);
605 const struct cls_table
*table
;
606 struct cls_rule
*next
;
608 next
= next_rule_in_list__(rule
);
609 if (next
->priority
< rule
->priority
) {
613 /* 'next' is the head of the list, that is, the rule that is included in
614 * the table's hmap. (This is important when the classifier contains rules
615 * that differ only in priority.) */
617 HMAP_FOR_EACH_CONTINUE (rule
, hmap_node
, &cursor
->table
->rules
) {
618 if (rule_matches(rule
, cursor
->target
)) {
623 table
= cursor
->table
;
624 HMAP_FOR_EACH_CONTINUE (table
, hmap_node
, &cursor
->cls
->tables
) {
625 rule
= search_table(table
, cursor
->target
);
627 cursor
->table
= table
;
635 static struct cls_table
*
636 find_table(const struct classifier
*cls
, const struct minimask
*mask
)
638 struct cls_table
*table
;
640 HMAP_FOR_EACH_IN_BUCKET (table
, hmap_node
, minimask_hash(mask
, 0),
642 if (minimask_equal(mask
, &table
->mask
)) {
649 static struct cls_table
*
650 insert_table(struct classifier
*cls
, const struct minimask
*mask
)
652 uint32_t hash
= minimask_hash(mask
, 0);
653 struct cls_table
*table
;
655 table
= xzalloc(sizeof *table
);
656 hmap_init(&table
->rules
);
657 minimask_clone(&table
->mask
, mask
);
658 hmap_insert(&cls
->tables
, &table
->hmap_node
, minimask_hash(mask
, 0));
659 list_push_back(&cls
->tables_priority
, &table
->list_node
);
660 table
->tag
= (minimask_get_metadata_mask(mask
) == OVS_BE64_MAX
661 ? tag_create_deterministic(hash
)
668 destroy_table(struct classifier
*cls
, struct cls_table
*table
)
670 minimask_destroy(&table
->mask
);
671 hmap_remove(&cls
->tables
, &table
->hmap_node
);
672 hmap_destroy(&table
->rules
);
673 list_remove(&table
->list_node
);
677 /* This function performs the following updates for 'table' in 'cls' following
678 * the addition of a new rule with priority 'new_priority' to 'table':
680 * - Update 'table->max_priority' and 'table->max_count' if necessary.
682 * - Update 'table''s position in 'cls->tables_priority' if necessary.
684 * This function should only be called after adding a new rule, not after
685 * replacing a rule by an identical one or modifying a rule in-place. */
687 update_tables_after_insertion(struct classifier
*cls
, struct cls_table
*table
,
688 unsigned int new_priority
)
690 if (new_priority
== table
->max_priority
) {
692 } else if (new_priority
> table
->max_priority
) {
693 struct cls_table
*iter
;
695 table
->max_priority
= new_priority
;
696 table
->max_count
= 1;
698 /* Possibly move 'table' earlier in the priority list. If we break out
699 * of the loop, then 'table' should be moved just after that 'iter'.
700 * If the loop terminates normally, then 'iter' will be the list head
701 * and we'll move table just after that (e.g. to the front of the
704 LIST_FOR_EACH_REVERSE_CONTINUE (iter
, list_node
,
705 &cls
->tables_priority
) {
706 if (iter
->max_priority
>= table
->max_priority
) {
711 /* Move 'table' just after 'iter' (unless it's already there). */
712 if (iter
->list_node
.next
!= &table
->list_node
) {
713 list_splice(iter
->list_node
.next
,
714 &table
->list_node
, table
->list_node
.next
);
719 /* This function performs the following updates for 'table' in 'cls' following
720 * the deletion of a rule with priority 'del_priority' from 'table':
722 * - Update 'table->max_priority' and 'table->max_count' if necessary.
724 * - Update 'table''s position in 'cls->tables_priority' if necessary.
726 * This function should only be called after removing a rule, not after
727 * replacing a rule by an identical one or modifying a rule in-place. */
729 update_tables_after_removal(struct classifier
*cls
, struct cls_table
*table
,
730 unsigned int del_priority
)
732 struct cls_table
*iter
;
734 if (del_priority
== table
->max_priority
&& --table
->max_count
== 0) {
735 struct cls_rule
*head
;
737 table
->max_priority
= 0;
738 HMAP_FOR_EACH (head
, hmap_node
, &table
->rules
) {
739 if (head
->priority
> table
->max_priority
) {
740 table
->max_priority
= head
->priority
;
741 table
->max_count
= 1;
742 } else if (head
->priority
== table
->max_priority
) {
747 /* Possibly move 'table' later in the priority list. If we break out
748 * of the loop, then 'table' should be moved just before that 'iter'.
749 * If the loop terminates normally, then 'iter' will be the list head
750 * and we'll move table just before that (e.g. to the back of the
753 LIST_FOR_EACH_CONTINUE (iter
, list_node
, &cls
->tables_priority
) {
754 if (iter
->max_priority
<= table
->max_priority
) {
759 /* Move 'table' just before 'iter' (unless it's already there). */
760 if (iter
->list_node
.prev
!= &table
->list_node
) {
761 list_splice(&iter
->list_node
,
762 &table
->list_node
, table
->list_node
.next
);
767 static struct cls_rule
*
768 find_match(const struct cls_table
*table
, const struct flow
*flow
)
770 uint32_t hash
= flow_hash_in_minimask(flow
, &table
->mask
, 0);
771 struct cls_rule
*rule
;
773 HMAP_FOR_EACH_WITH_HASH (rule
, hmap_node
, hash
, &table
->rules
) {
774 if (minimatch_matches_flow(&rule
->match
, flow
)) {
782 static struct cls_rule
*
783 find_equal(struct cls_table
*table
, const struct miniflow
*flow
, uint32_t hash
)
785 struct cls_rule
*head
;
787 HMAP_FOR_EACH_WITH_HASH (head
, hmap_node
, hash
, &table
->rules
) {
788 if (miniflow_equal(&head
->match
.flow
, flow
)) {
795 static struct cls_rule
*
796 insert_rule(struct classifier
*cls
,
797 struct cls_table
*table
, struct cls_rule
*new)
799 struct cls_rule
*head
;
800 struct cls_rule
*old
= NULL
;
802 new->hmap_node
.hash
= miniflow_hash_in_minimask(&new->match
.flow
,
803 &new->match
.mask
, 0);
805 head
= find_equal(table
, &new->match
.flow
, new->hmap_node
.hash
);
807 hmap_insert(&table
->rules
, &new->hmap_node
, new->hmap_node
.hash
);
808 list_init(&new->list
);
811 /* Scan the list for the insertion point that will keep the list in
812 * order of decreasing priority. */
813 struct cls_rule
*rule
;
814 FOR_EACH_RULE_IN_LIST (rule
, head
) {
815 if (new->priority
>= rule
->priority
) {
817 /* 'new' is the new highest-priority flow in the list. */
818 hmap_replace(&table
->rules
,
819 &rule
->hmap_node
, &new->hmap_node
);
822 if (new->priority
== rule
->priority
) {
823 list_replace(&new->list
, &rule
->list
);
827 list_insert(&rule
->list
, &new->list
);
833 /* Insert 'new' at the end of the list. */
834 list_push_back(&head
->list
, &new->list
);
839 update_tables_after_insertion(cls
, table
, new->priority
);
844 static struct cls_rule
*
845 next_rule_in_list__(struct cls_rule
*rule
)
847 struct cls_rule
*next
= OBJECT_CONTAINING(rule
->list
.next
, next
, list
);
851 static struct cls_rule
*
852 next_rule_in_list(struct cls_rule
*rule
)
854 struct cls_rule
*next
= next_rule_in_list__(rule
);
855 return next
->priority
< rule
->priority
? next
: NULL
;