/*
- * Copyright (c) 2009, 2010 Nicira Networks.
+ * Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include <assert.h>
#include <errno.h>
#include <netinet/in.h>
+#include "byte-order.h"
#include "dynamic-string.h"
#include "flow.h"
#include "hash.h"
+#include "odp-util.h"
+#include "ofp-util.h"
+#include "packets.h"
+
+static struct cls_table *find_table(const struct classifier *,
+ const struct minimask *);
+static struct cls_table *insert_table(struct classifier *,
+ const struct minimask *);
+
+static void destroy_table(struct classifier *, struct cls_table *);
+
+static struct cls_rule *find_match(const struct cls_table *,
+ const struct flow *);
+static struct cls_rule *find_equal(struct cls_table *,
+ const struct miniflow *, uint32_t hash);
+static struct cls_rule *insert_rule(struct cls_table *, struct cls_rule *);
+
+/* Iterates RULE over HEAD and all of the cls_rules on HEAD->list. */
+#define FOR_EACH_RULE_IN_LIST(RULE, HEAD) \
+ for ((RULE) = (HEAD); (RULE) != NULL; (RULE) = next_rule_in_list(RULE))
+#define FOR_EACH_RULE_IN_LIST_SAFE(RULE, NEXT, HEAD) \
+ for ((RULE) = (HEAD); \
+ (RULE) != NULL && ((NEXT) = next_rule_in_list(RULE), true); \
+ (RULE) = (NEXT))
+
+static struct cls_rule *next_rule_in_list__(struct cls_rule *);
+static struct cls_rule *next_rule_in_list(struct cls_rule *);
+\f
+/* cls_rule. */
-const struct cls_field cls_fields[CLS_N_FIELDS + 1] = {
-#define CLS_FIELD(WILDCARDS, MEMBER, NAME) \
- { offsetof(flow_t, MEMBER), \
- sizeof ((flow_t *)0)->MEMBER, \
- WILDCARDS, \
- #NAME },
- CLS_FIELDS
-#undef CLS_FIELD
- { sizeof(flow_t), 0, 0, "exact" },
-};
-
-static uint32_t hash_fields(const flow_t *, int table_idx);
-static bool equal_fields(const flow_t *, const flow_t *, int table_idx);
-
-static int table_idx_from_wildcards(uint32_t wildcards);
-static struct cls_rule *table_insert(struct hmap *, struct cls_rule *);
-static struct cls_rule *insert_exact_rule(struct classifier *,
- struct cls_rule *);
-static struct cls_bucket *find_bucket(struct hmap *, size_t hash,
- const struct cls_rule *);
-static struct cls_rule *search_table(const struct hmap *table, int field_idx,
- const struct cls_rule *);
-static struct cls_rule *search_exact_table(const struct classifier *,
- size_t hash, const flow_t *);
-static bool rules_match_1wild(const struct cls_rule *fixed,
- const struct cls_rule *wild, int field_idx);
-static bool rules_match_2wild(const struct cls_rule *wild1,
- const struct cls_rule *wild2, int field_idx);
-
-/* Converts the flow in 'flow' into a cls_rule in 'rule', with the given
- * 'wildcards' and 'priority'.*/
+/* Initializes 'rule' to match packets specified by 'match' at the given
+ * 'priority'. 'match' must satisfy the invariant described in the comment at
+ * the definition of struct match.
+ *
+ * The caller must eventually destroy 'rule' with cls_rule_destroy().
+ *
+ * (OpenFlow uses priorities between 0 and UINT16_MAX, inclusive, but
+ * internally Open vSwitch supports a wider range.) */
void
-cls_rule_from_flow(struct cls_rule *rule, const flow_t *flow,
- uint32_t wildcards, unsigned int priority)
+cls_rule_init(struct cls_rule *rule,
+ const struct match *match, unsigned int priority)
{
- assert(!flow->reserved[0] && !flow->reserved[1] && !flow->reserved[2]);
- rule->flow = *flow;
- flow_wildcards_init(&rule->wc, wildcards);
+ minimatch_init(&rule->match, match);
rule->priority = priority;
- rule->table_idx = table_idx_from_wildcards(rule->wc.wildcards);
}
-/* Converts the ofp_match in 'match' into a cls_rule in 'rule', with the given
- * 'priority'. */
+/* Same as cls_rule_init() for initialization from a "struct minimatch". */
void
-cls_rule_from_match(struct cls_rule *rule, const struct ofp_match *match,
- unsigned int priority)
+cls_rule_init_from_minimatch(struct cls_rule *rule,
+ const struct minimatch *match,
+ unsigned int priority)
{
- uint32_t wildcards;
- flow_from_match(&rule->flow, &wildcards, match);
- flow_wildcards_init(&rule->wc, wildcards);
- rule->priority = rule->wc.wildcards ? priority : UINT16_MAX;
- rule->table_idx = table_idx_from_wildcards(rule->wc.wildcards);
+ minimatch_clone(&rule->match, match);
+ rule->priority = priority;
}
-/* Converts 'rule' to a string and returns the string. The caller must free
- * the string (with free()). */
-char *
-cls_rule_to_string(const struct cls_rule *rule)
+/* Initializes 'dst' as a copy of 'src'.
+ *
+ * The caller must eventually destroy 'rule' with cls_rule_destroy(). */
+void
+cls_rule_clone(struct cls_rule *dst, const struct cls_rule *src)
{
- struct ds s = DS_EMPTY_INITIALIZER;
- ds_put_format(&s, "wildcards=%x priority=%u ",
- rule->wc.wildcards, rule->priority);
- flow_format(&s, &rule->flow);
- return ds_cstr(&s);
+ minimatch_clone(&dst->match, &src->match);
+ dst->priority = src->priority;
}
-/* Prints cls_rule 'rule', for debugging.
+/* Frees memory referenced by 'rule'. Doesn't free 'rule' itself (it's
+ * normally embedded into a larger structure).
*
- * (The output could be improved and expanded, but this was good enough to
- * debug the classifier.) */
+ * ('rule' must not currently be in a classifier.) */
void
-cls_rule_print(const struct cls_rule *rule)
+cls_rule_destroy(struct cls_rule *rule)
{
- printf("wildcards=%x priority=%u ", rule->wc.wildcards, rule->priority);
- flow_print(stdout, &rule->flow);
- putc('\n', stdout);
+ minimatch_destroy(&rule->match);
}
-/* Adjusts pointers around 'old', which must be in classifier 'cls', to
- * compensate for it having been moved in memory to 'new' (e.g. due to
- * realloc()).
- *
- * This function cannot be realized in all possible flow classifier
- * implementations, so we will probably have to change the interface if we
- * change the implementation. Shouldn't be a big deal though. */
-void
-cls_rule_moved(struct classifier *cls, struct cls_rule *old,
- struct cls_rule *new)
-{
- if (old != new) {
- if (new->wc.wildcards) {
- list_moved(&new->node.list);
- } else {
- hmap_node_moved(&cls->exact_table,
- &old->node.hmap, &new->node.hmap);
- }
- }
+/* Returns true if 'a' and 'b' match the same packets at the same priority,
+ * false if they differ in some way. */
+bool
+cls_rule_equal(const struct cls_rule *a, const struct cls_rule *b)
+{
+ return a->priority == b->priority && minimatch_equal(&a->match, &b->match);
}
-/* Replaces 'old', which must be in classifier 'cls', by 'new' (e.g. due to
- * realloc()); that is, after calling this function 'new' will be in 'cls' in
- * place of 'old'.
- *
- * 'new' and 'old' must be exactly the same: wildcard the same fields, have the
- * same fixed values for non-wildcarded fields, and have the same priority.
- *
- * The caller takes ownership of 'old' and is thus responsible for freeing it,
- * etc., as necessary.
- *
- * This function cannot be realized in all possible flow classifier
- * implementations, so we will probably have to change the interface if we
- * change the implementation. Shouldn't be a big deal though. */
+/* Returns a hash value for 'rule', folding in 'basis'. */
+uint32_t
+cls_rule_hash(const struct cls_rule *rule, uint32_t basis)
+{
+ return minimatch_hash(&rule->match, hash_int(rule->priority, basis));
+}
+
+/* Appends a string describing 'rule' to 's'. */
void
-cls_rule_replace(struct classifier *cls, const struct cls_rule *old,
- struct cls_rule *new)
+cls_rule_format(const struct cls_rule *rule, struct ds *s)
{
- assert(old != new);
- assert(old->wc.wildcards == new->wc.wildcards);
- assert(old->priority == new->priority);
+ minimatch_format(&rule->match, s, rule->priority);
+}
- if (new->wc.wildcards) {
- list_replace(&new->node.list, &old->node.list);
- } else {
- hmap_replace(&cls->exact_table, &old->node.hmap, &new->node.hmap);
- }
+/* Returns true if 'rule' matches every packet, false otherwise. */
+bool
+cls_rule_is_catchall(const struct cls_rule *rule)
+{
+ return minimask_is_catchall(&rule->match.mask);
}
\f
/* Initializes 'cls' as a classifier that initially contains no classification
void
classifier_init(struct classifier *cls)
{
- int i;
-
cls->n_rules = 0;
- for (i = 0; i < ARRAY_SIZE(cls->tables); i++) {
- hmap_init(&cls->tables[i]);
- }
- hmap_init(&cls->exact_table);
+ hmap_init(&cls->tables);
}
/* Destroys 'cls'. Rules within 'cls', if any, are not freed; this is the
classifier_destroy(struct classifier *cls)
{
if (cls) {
- struct cls_bucket *bucket, *next_bucket;
- struct hmap *tbl;
+ struct cls_table *table, *next_table;
- for (tbl = &cls->tables[0]; tbl < &cls->tables[CLS_N_FIELDS]; tbl++) {
- HMAP_FOR_EACH_SAFE (bucket, next_bucket,
- struct cls_bucket, hmap_node, tbl) {
- free(bucket);
- }
- hmap_destroy(tbl);
+ HMAP_FOR_EACH_SAFE (table, next_table, hmap_node, &cls->tables) {
+ hmap_destroy(&table->rules);
+ hmap_remove(&cls->tables, &table->hmap_node);
+ free(table);
}
- hmap_destroy(&cls->exact_table);
+ hmap_destroy(&cls->tables);
}
}
-/* Returns true if 'cls' does not contain any classification rules, false
- * otherwise. */
+/* Returns true if 'cls' contains no classification rules, false otherwise. */
bool
classifier_is_empty(const struct classifier *cls)
{
return cls->n_rules == 0;
}
-/* Returns the number of rules in 'classifier'. */
+/* Returns the number of rules in 'cls'. */
int
classifier_count(const struct classifier *cls)
{
return cls->n_rules;
}
-/* Returns the number of rules in 'classifier' that have no wildcards. */
-int
-classifier_count_exact(const struct classifier *cls)
-{
- return hmap_count(&cls->exact_table);
-}
-
-/* Inserts 'rule' into 'cls'. Transfers ownership of 'rule' to 'cls'.
+/* Inserts 'rule' into 'cls'. Until 'rule' is removed from 'cls', the caller
+ * must not modify or free it.
*
* If 'cls' already contains an identical rule (including wildcards, values of
* fixed fields, and priority), replaces the old rule by 'rule' and returns the
* rule that was replaced. The caller takes ownership of the returned rule and
- * is thus responsible for freeing it, etc., as necessary.
+ * is thus responsible for destroying it with cls_rule_destroy(), freeing the
+ * memory block in which it resides, etc., as necessary.
*
* Returns NULL if 'cls' does not contain a rule with an identical key, after
* inserting the new rule. In this case, no rules are displaced by the new
* rule, even rules that cannot have any effect because the new rule matches a
* superset of their flows and has higher priority. */
struct cls_rule *
-classifier_insert(struct classifier *cls, struct cls_rule *rule)
+classifier_replace(struct classifier *cls, struct cls_rule *rule)
{
- struct cls_rule *old;
- assert((rule->wc.wildcards == 0) == (rule->table_idx == CLS_F_IDX_EXACT));
- old = (rule->wc.wildcards
- ? table_insert(&cls->tables[rule->table_idx], rule)
- : insert_exact_rule(cls, rule));
- if (!old) {
+ struct cls_rule *old_rule;
+ struct cls_table *table;
+
+ table = find_table(cls, &rule->match.mask);
+ if (!table) {
+ table = insert_table(cls, &rule->match.mask);
+ }
+
+ old_rule = insert_rule(table, rule);
+ if (!old_rule) {
+ table->n_table_rules++;
cls->n_rules++;
}
- return old;
+ return old_rule;
}
-/* Inserts 'rule' into 'cls'. Transfers ownership of 'rule' to 'cls'.
+/* Inserts 'rule' into 'cls'. Until 'rule' is removed from 'cls', the caller
+ * must not modify or free it.
*
- * 'rule' must be an exact-match rule (rule->wc.wildcards must be 0) and 'cls'
- * must not contain any rule with an identical key. */
+ * 'cls' must not contain an identical rule (including wildcards, values of
+ * fixed fields, and priority). Use classifier_find_rule_exactly() to find
+ * such a rule. */
void
-classifier_insert_exact(struct classifier *cls, struct cls_rule *rule)
+classifier_insert(struct classifier *cls, struct cls_rule *rule)
{
- hmap_insert(&cls->exact_table, &rule->node.hmap,
- flow_hash(&rule->flow, 0));
- cls->n_rules++;
+ struct cls_rule *displaced_rule = classifier_replace(cls, rule);
+ assert(!displaced_rule);
}
-/* Removes 'rule' from 'cls'. It is caller's responsibility to free 'rule', if
- * this is desirable. */
+/* Removes 'rule' from 'cls'. It is the caller's responsibility to destroy
+ * 'rule' with cls_rule_destroy(), freeing the memory block in which 'rule'
+ * resides, etc., as necessary. */
void
classifier_remove(struct classifier *cls, struct cls_rule *rule)
{
- if (rule->wc.wildcards) {
- /* Remove 'rule' from bucket. If that empties the bucket, remove the
- * bucket from its table. */
- struct hmap *table = &cls->tables[rule->table_idx];
- struct list *rules = list_remove(&rule->node.list);
- if (list_is_empty(rules)) {
- /* This code is a little tricky. list_remove() returns the list
- * element just after the one removed. Since the list is now
- * empty, this will be the address of the 'rules' member of the
- * bucket that was just emptied, so pointer arithmetic (via
- * CONTAINER_OF) can find that bucket. */
- struct cls_bucket *bucket;
- bucket = CONTAINER_OF(rules, struct cls_bucket, rules);
- hmap_remove(table, &bucket->hmap_node);
- free(bucket);
- }
+ struct cls_rule *head;
+ struct cls_table *table;
+
+ table = find_table(cls, &rule->match.mask);
+ head = find_equal(table, &rule->match.flow, rule->hmap_node.hash);
+ if (head != rule) {
+ list_remove(&rule->list);
+ } else if (list_is_empty(&rule->list)) {
+ hmap_remove(&table->rules, &rule->hmap_node);
} else {
- /* Remove 'rule' from cls->exact_table. */
- hmap_remove(&cls->exact_table, &rule->node.hmap);
+ struct cls_rule *next = CONTAINER_OF(rule->list.next,
+ struct cls_rule, list);
+
+ list_remove(&rule->list);
+ hmap_replace(&table->rules, &rule->hmap_node, &next->hmap_node);
+ }
+
+ if (--table->n_table_rules == 0) {
+ destroy_table(cls, table);
}
+
cls->n_rules--;
}
/* Finds and returns the highest-priority rule in 'cls' that matches 'flow'.
* Returns a null pointer if no rules in 'cls' match 'flow'. If multiple rules
- * of equal priority match 'flow', returns one arbitrarily.
- *
- * (When multiple rules of equal priority happen to fall into the same bucket,
- * rules added more recently take priority over rules added less recently, but
- * this is subject to change and should not be depended upon.) */
+ * of equal priority match 'flow', returns one arbitrarily. */
struct cls_rule *
-classifier_lookup(const struct classifier *cls, const flow_t *flow)
+classifier_lookup(const struct classifier *cls, const struct flow *flow)
{
- struct cls_rule *rule = classifier_lookup_exact(cls, flow);
- if (!rule) {
- rule = classifier_lookup_wild(cls, flow);
- }
- return rule;
-}
+ struct cls_table *table;
+ struct cls_rule *best;
-struct cls_rule *
-classifier_lookup_exact(const struct classifier *cls, const flow_t *flow)
-{
- return (!hmap_is_empty(&cls->exact_table)
- ? search_exact_table(cls, flow_hash(flow, 0), flow)
- : NULL);
-}
-
-struct cls_rule *
-classifier_lookup_wild(const struct classifier *cls, const flow_t *flow)
-{
- struct cls_rule *best = NULL;
- if (cls->n_rules > hmap_count(&cls->exact_table)) {
- struct cls_rule target;
- int i;
-
- cls_rule_from_flow(&target, flow, 0, 0);
- for (i = 0; i < CLS_N_FIELDS; i++) {
- struct cls_rule *rule = search_table(&cls->tables[i], i, &target);
- if (rule && (!best || rule->priority > best->priority)) {
- best = rule;
- }
+ best = NULL;
+ HMAP_FOR_EACH (table, hmap_node, &cls->tables) {
+ struct cls_rule *rule = find_match(table, flow);
+ if (rule && (!best || rule->priority > best->priority)) {
+ best = rule;
}
}
return best;
}
+/* Finds and returns a rule in 'cls' with exactly the same priority and
+ * matching criteria as 'target'. Returns a null pointer if 'cls' doesn't
+ * contain an exact match. */
struct cls_rule *
classifier_find_rule_exactly(const struct classifier *cls,
- const flow_t *target, uint32_t wildcards,
- unsigned int priority)
+ const struct cls_rule *target)
{
- struct cls_bucket *bucket;
- int table_idx;
- uint32_t hash;
+ struct cls_rule *head, *rule;
+ struct cls_table *table;
- if (!wildcards) {
- /* Ignores 'priority'. */
- return search_exact_table(cls, flow_hash(target, 0), target);
+ table = find_table(cls, &target->match.mask);
+ if (!table) {
+ return NULL;
}
- assert(wildcards == (wildcards & OFPFW_ALL));
- table_idx = table_idx_from_wildcards(wildcards);
- hash = hash_fields(target, table_idx);
- HMAP_FOR_EACH_WITH_HASH (bucket, struct cls_bucket, hmap_node, hash,
- &cls->tables[table_idx]) {
- if (equal_fields(&bucket->fixed, target, table_idx)) {
- struct cls_rule *pos;
- LIST_FOR_EACH (pos, struct cls_rule, node.list, &bucket->rules) {
- if (pos->priority < priority) {
- return NULL;
- } else if (pos->priority == priority &&
- pos->wc.wildcards == wildcards &&
- flow_equal(target, &pos->flow)) {
- return pos;
- }
- }
+ head = find_equal(table, &target->match.flow,
+ miniflow_hash_in_minimask(&target->match.flow,
+ &target->match.mask, 0));
+ FOR_EACH_RULE_IN_LIST (rule, head) {
+ if (target->priority >= rule->priority) {
+ return target->priority == rule->priority ? rule : NULL;
}
}
return NULL;
}
-/* Checks if the flow defined by 'target' with 'wildcards' at 'priority'
- * overlaps with any other rule at the same priority in the classifier.
- * Two rules are considered overlapping if a packet could match both. */
-bool
-classifier_rule_overlaps(const struct classifier *cls,
- const flow_t *target, uint32_t wildcards,
- unsigned int priority)
+/* Finds and returns a rule in 'cls' with priority 'priority' and exactly the
+ * same matching criteria as 'target'. Returns a null pointer if 'cls' doesn't
+ * contain an exact match. */
+struct cls_rule *
+classifier_find_match_exactly(const struct classifier *cls,
+ const struct match *target,
+ unsigned int priority)
{
- struct cls_rule target_rule;
- const struct hmap *tbl;
+ struct cls_rule *retval;
+ struct cls_rule cr;
- if (!wildcards) {
- return search_exact_table(cls, flow_hash(target, 0), target) ?
- true : false;
- }
+ cls_rule_init(&cr, target, priority);
+ retval = classifier_find_rule_exactly(cls, &cr);
+ cls_rule_destroy(&cr);
+
+ return retval;
+}
- cls_rule_from_flow(&target_rule, target, wildcards, priority);
+/* Checks if 'target' would overlap any other rule in 'cls'. Two rules are
+ * considered to overlap if both rules have the same priority and a packet
+ * could match both. */
+bool
+classifier_rule_overlaps(const struct classifier *cls,
+ const struct cls_rule *target)
+{
+ struct cls_table *table;
- for (tbl = &cls->tables[0]; tbl < &cls->tables[CLS_N_FIELDS]; tbl++) {
- struct cls_bucket *bucket;
+ HMAP_FOR_EACH (table, hmap_node, &cls->tables) {
+ uint32_t storage[FLOW_U32S];
+ struct minimask mask;
+ struct cls_rule *head;
- HMAP_FOR_EACH (bucket, struct cls_bucket, hmap_node, tbl) {
+ minimask_combine(&mask, &target->match.mask, &table->mask, storage);
+ HMAP_FOR_EACH (head, hmap_node, &table->rules) {
struct cls_rule *rule;
- LIST_FOR_EACH (rule, struct cls_rule, node.list,
- &bucket->rules) {
- if (rule->priority == priority
- && rules_match_2wild(rule, &target_rule, 0)) {
+ FOR_EACH_RULE_IN_LIST (rule, head) {
+ if (rule->priority == target->priority
+ && miniflow_equal_in_minimask(&target->match.flow,
+ &rule->match.flow, &mask)) {
return true;
}
}
return false;
}
-/* Ignores target->priority.
+/* Returns true if 'rule' exactly matches 'criteria' or if 'rule' is more
+ * specific than 'criteria'. That is, 'rule' matches 'criteria' and this
+ * function returns true if, for every field:
*
- * 'callback' is allowed to delete the rule that is passed as its argument, but
- * it must not delete (or move) any other rules in 'cls' that are in the same
- * table as the argument rule. Two rules are in the same table if their
- * cls_rule structs have the same table_idx; as a special case, a rule with
- * wildcards and an exact-match rule will never be in the same table. */
-void
-classifier_for_each_match(const struct classifier *cls,
- const struct cls_rule *target,
- int include, cls_cb_func *callback, void *aux)
-{
- if (include & CLS_INC_WILD) {
- const struct hmap *table;
-
- for (table = &cls->tables[0]; table < &cls->tables[CLS_N_FIELDS];
- table++) {
- struct cls_bucket *bucket, *next_bucket;
-
- HMAP_FOR_EACH_SAFE (bucket, next_bucket,
- struct cls_bucket, hmap_node, table) {
- /* XXX there is a bit of room for optimization here based on
- * rejecting entire buckets on their fixed fields, but it will
- * only be worthwhile for big buckets (which we hope we won't
- * get anyway, but...) */
- struct cls_rule *prev_rule, *rule;
-
- /* We can't just use LIST_FOR_EACH_SAFE here because, if the
- * callback deletes the last rule in the bucket, then the
- * bucket itself will be destroyed. The bucket contains the
- * list head so that's a use-after-free error. */
- prev_rule = NULL;
- LIST_FOR_EACH (rule, struct cls_rule, node.list,
- &bucket->rules) {
- if (rules_match_1wild(rule, target, 0)) {
- if (prev_rule) {
- callback(prev_rule, aux);
- }
- prev_rule = rule;
- }
- }
- if (prev_rule) {
- callback(prev_rule, aux);
- }
- }
- }
- }
-
- if (include & CLS_INC_EXACT) {
- if (target->wc.wildcards) {
- struct cls_rule *rule, *next_rule;
-
- HMAP_FOR_EACH_SAFE (rule, next_rule, struct cls_rule, node.hmap,
- &cls->exact_table) {
- if (rules_match_1wild(rule, target, 0)) {
- callback(rule, aux);
- }
- }
- } else {
- /* Optimization: there can be at most one match in the exact
- * table. */
- size_t hash = flow_hash(&target->flow, 0);
- struct cls_rule *rule = search_exact_table(cls, hash,
- &target->flow);
- if (rule) {
- callback(rule, aux);
- }
- }
- }
-}
-
-/* 'callback' is allowed to delete the rule that is passed as its argument, but
- * it must not delete (or move) any other rules in 'cls' that are in the same
- * table as the argument rule. Two rules are in the same table if their
- * cls_rule structs have the same table_idx; as a special case, a rule with
- * wildcards and an exact-match rule will never be in the same table. */
-void
-classifier_for_each(const struct classifier *cls, int include,
- void (*callback)(struct cls_rule *, void *aux),
- void *aux)
-{
- if (include & CLS_INC_WILD) {
- const struct hmap *tbl;
-
- for (tbl = &cls->tables[0]; tbl < &cls->tables[CLS_N_FIELDS]; tbl++) {
- struct cls_bucket *bucket, *next_bucket;
-
- HMAP_FOR_EACH_SAFE (bucket, next_bucket,
- struct cls_bucket, hmap_node, tbl) {
- struct cls_rule *prev_rule, *rule;
-
- /* We can't just use LIST_FOR_EACH_SAFE here because, if the
- * callback deletes the last rule in the bucket, then the
- * bucket itself will be destroyed. The bucket contains the
- * list head so that's a use-after-free error. */
- prev_rule = NULL;
- LIST_FOR_EACH (rule, struct cls_rule, node.list,
- &bucket->rules) {
- if (prev_rule) {
- callback(prev_rule, aux);
- }
- prev_rule = rule;
- }
- if (prev_rule) {
- callback(prev_rule, aux);
- }
- }
- }
- }
-
- if (include & CLS_INC_EXACT) {
- struct cls_rule *rule, *next_rule;
-
- HMAP_FOR_EACH_SAFE (rule, next_rule,
- struct cls_rule, node.hmap, &cls->exact_table) {
- callback(rule, aux);
- }
- }
+ * - 'criteria' and 'rule' specify the same (non-wildcarded) value for the
+ * field, or
+ *
+ * - 'criteria' wildcards the field,
+ *
+ * Conversely, 'rule' does not match 'criteria' and this function returns false
+ * if, for at least one field:
+ *
+ * - 'criteria' and 'rule' specify different values for the field, or
+ *
+ * - 'criteria' specifies a value for the field but 'rule' wildcards it.
+ *
+ * Equivalently, the truth table for whether a field matches is:
+ *
+ * rule
+ *
+ * c wildcard exact
+ * r +---------+---------+
+ * i wild | yes | yes |
+ * t card | | |
+ * e +---------+---------+
+ * r exact | no |if values|
+ * i | |are equal|
+ * a +---------+---------+
+ *
+ * This is the matching rule used by OpenFlow 1.0 non-strict OFPT_FLOW_MOD
+ * commands and by OpenFlow 1.0 aggregate and flow stats.
+ *
+ * Ignores rule->priority. */
+bool
+cls_rule_is_loose_match(const struct cls_rule *rule,
+ const struct minimatch *criteria)
+{
+ return (!minimask_has_extra(&rule->match.mask, &criteria->mask)
+ && miniflow_equal_in_minimask(&rule->match.flow, &criteria->flow,
+ &criteria->mask));
}
\f
-static struct cls_bucket *create_bucket(struct hmap *, size_t hash,
- const flow_t *fixed);
-static struct cls_rule *bucket_insert(struct cls_bucket *, struct cls_rule *);
-
-static inline bool equal_bytes(const void *, const void *, size_t n);
-
-/* Returns a hash computed across the fields in 'flow' whose field indexes
- * (CLS_F_IDX_*) are less than 'table_idx'. (If 'table_idx' is
- * CLS_F_IDX_EXACT, hashes all the fields in 'flow'). */
-static uint32_t
-hash_fields(const flow_t *flow, int table_idx)
-{
- /* I just know I'm going to hell for writing code this way.
- *
- * GCC generates pretty good code here, with only a single taken
- * conditional jump per execution. Now the question is, would we be better
- * off marking this function ALWAYS_INLINE and writing a wrapper that
- * switches on the value of 'table_idx' to get rid of all the conditional
- * jumps entirely (except for one in the wrapper)? Honestly I really,
- * really hope that it doesn't matter in practice.
- *
- * We could do better by calculating hashes incrementally, instead of
- * starting over from the top each time. But that would be even uglier. */
- uint32_t a, b, c;
- uint32_t tmp[3];
- size_t n;
-
- a = b = c = 0xdeadbeef + table_idx;
- n = 0;
-
-#define CLS_FIELD(WILDCARDS, MEMBER, NAME) \
- if (table_idx == CLS_F_IDX_##NAME) { \
- /* Done. */ \
- memset((uint8_t *) tmp + n, 0, sizeof tmp - n); \
- goto finish; \
- } else { \
- const size_t size = sizeof flow->MEMBER; \
- const uint8_t *p1 = (const uint8_t *) &flow->MEMBER; \
- const size_t p1_size = MIN(sizeof tmp - n, size); \
- const uint8_t *p2 = p1 + p1_size; \
- const size_t p2_size = size - p1_size; \
- \
- /* Append to 'tmp' as much data as will fit. */ \
- memcpy((uint8_t *) tmp + n, p1, p1_size); \
- n += p1_size; \
- \
- /* If 'tmp' is full, mix. */ \
- if (n == sizeof tmp) { \
- a += tmp[0]; \
- b += tmp[1]; \
- c += tmp[2]; \
- HASH_MIX(a, b, c); \
- n = 0; \
- } \
- \
- /* Append to 'tmp' any data that didn't fit. */ \
- memcpy(tmp, p2, p2_size); \
- n += p2_size; \
- }
- CLS_FIELDS
-#undef CLS_FIELD
+/* Iteration. */
-finish:
- a += tmp[0];
- b += tmp[1];
- c += tmp[2];
- HASH_FINAL(a, b, c);
- return c;
-}
-
-/* Compares the fields in 'a' and 'b' whose field indexes (CLS_F_IDX_*) are
- * less than 'table_idx'. (If 'table_idx' is CLS_F_IDX_EXACT, compares all the
- * fields in 'a' and 'b').
- *
- * Returns true if all the compared fields are equal, false otherwise. */
static bool
-equal_fields(const flow_t *a, const flow_t *b, int table_idx)
-{
- /* XXX The generated code could be better here. */
-#define CLS_FIELD(WILDCARDS, MEMBER, NAME) \
- if (table_idx == CLS_F_IDX_##NAME) { \
- return true; \
- } else if (!equal_bytes(&a->MEMBER, &b->MEMBER, sizeof a->MEMBER)) { \
- return false; \
- }
- CLS_FIELDS
-#undef CLS_FIELD
-
- return true;
-}
-
-static int
-table_idx_from_wildcards(uint32_t wildcards)
+rule_matches(const struct cls_rule *rule, const struct cls_rule *target)
{
- if (!wildcards) {
- return CLS_F_IDX_EXACT;
- }
-#define CLS_FIELD(WILDCARDS, MEMBER, NAME) \
- if (wildcards & WILDCARDS) { \
- return CLS_F_IDX_##NAME; \
- }
- CLS_FIELDS
-#undef CLS_FIELD
- NOT_REACHED();
+ return (!target
+ || miniflow_equal_in_minimask(&rule->match.flow,
+ &target->match.flow,
+ &target->match.mask));
}
-/* Inserts 'rule' into 'table'. Returns the rule, if any, that was displaced
- * in favor of 'rule'. */
static struct cls_rule *
-table_insert(struct hmap *table, struct cls_rule *rule)
+search_table(const struct cls_table *table, const struct cls_rule *target)
{
- struct cls_bucket *bucket;
- size_t hash;
-
- hash = hash_fields(&rule->flow, rule->table_idx);
- bucket = find_bucket(table, hash, rule);
- if (!bucket) {
- bucket = create_bucket(table, hash, &rule->flow);
- }
-
- return bucket_insert(bucket, rule);
-}
+ if (!target || !minimask_has_extra(&table->mask, &target->match.mask)) {
+ struct cls_rule *rule;
-/* Inserts 'rule' into 'bucket', given that 'field' is the first wildcarded
- * field in 'rule'.
- *
- * Returns the rule, if any, that was displaced in favor of 'rule'. */
-static struct cls_rule *
-bucket_insert(struct cls_bucket *bucket, struct cls_rule *rule)
-{
- struct cls_rule *pos;
- LIST_FOR_EACH (pos, struct cls_rule, node.list, &bucket->rules) {
- if (pos->priority == rule->priority) {
- if (pos->wc.wildcards == rule->wc.wildcards
- && rules_match_1wild(pos, rule, rule->table_idx))
- {
- list_replace(&rule->node.list, &pos->node.list);
- return pos;
+ HMAP_FOR_EACH (rule, hmap_node, &table->rules) {
+ if (rule_matches(rule, target)) {
+ return rule;
}
- } else if (pos->priority < rule->priority) {
- break;
}
}
- list_insert(&pos->node.list, &rule->node.list);
return NULL;
}
-static struct cls_rule *
-insert_exact_rule(struct classifier *cls, struct cls_rule *rule)
+/* Initializes 'cursor' for iterating through rules in 'cls':
+ *
+ * - If 'target' is null, the cursor will visit every rule in 'cls'.
+ *
+ * - If 'target' is nonnull, the cursor will visit each 'rule' in 'cls'
+ * such that cls_rule_is_loose_match(rule, target) returns true.
+ *
+ * Ignores target->priority. */
+void
+cls_cursor_init(struct cls_cursor *cursor, const struct classifier *cls,
+ const struct cls_rule *target)
{
- struct cls_rule *old_rule;
- size_t hash;
-
- hash = flow_hash(&rule->flow, 0);
- old_rule = search_exact_table(cls, hash, &rule->flow);
- if (old_rule) {
- hmap_remove(&cls->exact_table, &old_rule->node.hmap);
- }
- hmap_insert(&cls->exact_table, &rule->node.hmap, hash);
- return old_rule;
+ cursor->cls = cls;
+ cursor->target = target && !cls_rule_is_catchall(target) ? target : NULL;
}
-/* Returns the bucket in 'table' that has the given 'hash' and the same fields
- * as 'rule->flow' (up to 'rule->table_idx'), or a null pointer if no bucket
- * matches. */
-static struct cls_bucket *
-find_bucket(struct hmap *table, size_t hash, const struct cls_rule *rule)
+/* Returns the first matching cls_rule in 'cursor''s iteration, or a null
+ * pointer if there are no matches. */
+struct cls_rule *
+cls_cursor_first(struct cls_cursor *cursor)
{
- struct cls_bucket *bucket;
- HMAP_FOR_EACH_WITH_HASH (bucket, struct cls_bucket, hmap_node, hash,
- table) {
- if (equal_fields(&bucket->fixed, &rule->flow, rule->table_idx)) {
- return bucket;
+ struct cls_table *table;
+
+ HMAP_FOR_EACH (table, hmap_node, &cursor->cls->tables) {
+ struct cls_rule *rule = search_table(table, cursor->target);
+ if (rule) {
+ cursor->table = table;
+ return rule;
}
}
+
return NULL;
}
-/* Creates a bucket and inserts it in 'table' with the given 'hash' and 'fixed'
- * values. Returns the new bucket. */
-static struct cls_bucket *
-create_bucket(struct hmap *table, size_t hash, const flow_t *fixed)
+/* Returns the next matching cls_rule in 'cursor''s iteration, or a null
+ * pointer if there are no more matches. */
+struct cls_rule *
+cls_cursor_next(struct cls_cursor *cursor, struct cls_rule *rule)
{
- struct cls_bucket *bucket = xmalloc(sizeof *bucket);
- list_init(&bucket->rules);
- bucket->fixed = *fixed;
- hmap_insert(table, &bucket->hmap_node, hash);
- return bucket;
-}
+ const struct cls_table *table;
+ struct cls_rule *next;
-/* Returns true if the 'n' bytes in 'a' and 'b' are equal, false otherwise. */
-static inline bool ALWAYS_INLINE
-equal_bytes(const void *a, const void *b, size_t n)
-{
-#ifdef __i386__
- /* For some reason GCC generates stupid code for memcmp() of small
- * constant integer lengths. Help it out.
- *
- * This function is always inlined, and it is always called with 'n' as a
- * compile-time constant, so the switch statement gets optimized out and
- * this whole function just expands to an instruction or two. */
- switch (n) {
- case 1:
- return *(uint8_t *) a == *(uint8_t *) b;
+ next = next_rule_in_list__(rule);
+ if (next->priority < rule->priority) {
+ return next;
+ }
- case 2:
- return *(uint16_t *) a == *(uint16_t *) b;
+ /* 'next' is the head of the list, that is, the rule that is included in
+ * the table's hmap. (This is important when the classifier contains rules
+ * that differ only in priority.) */
+ rule = next;
+ HMAP_FOR_EACH_CONTINUE (rule, hmap_node, &cursor->table->rules) {
+ if (rule_matches(rule, cursor->target)) {
+ return rule;
+ }
+ }
- case 4:
- return *(uint32_t *) a == *(uint32_t *) b;
+ table = cursor->table;
+ HMAP_FOR_EACH_CONTINUE (table, hmap_node, &cursor->cls->tables) {
+ rule = search_table(table, cursor->target);
+ if (rule) {
+ cursor->table = table;
+ return rule;
+ }
+ }
- case 6:
- return (*(uint32_t *) a == *(uint32_t *) b
- && ((uint16_t *) a)[2] == ((uint16_t *) b)[2]);
+ return NULL;
+}
+\f
+static struct cls_table *
+find_table(const struct classifier *cls, const struct minimask *mask)
+{
+ struct cls_table *table;
- default:
- abort();
+ HMAP_FOR_EACH_IN_BUCKET (table, hmap_node, minimask_hash(mask, 0),
+ &cls->tables) {
+ if (minimask_equal(mask, &table->mask)) {
+ return table;
+ }
}
-#else
- /* I hope GCC is smarter on your platform. */
- return !memcmp(a, b, n);
-#endif
+ return NULL;
}
-/* Returns the 32-bit unsigned integer at 'p'. */
-static inline uint32_t
-read_uint32(const void *p)
+static struct cls_table *
+insert_table(struct classifier *cls, const struct minimask *mask)
{
- /* GCC optimizes this into a single machine instruction on x86. */
- uint32_t x;
- memcpy(&x, p, sizeof x);
- return x;
-}
+ struct cls_table *table;
-/* Compares the specified field in 'a' and 'b'. Returns true if the fields are
- * equal, or if the ofp_match wildcard bits in 'wildcards' are set such that
- * non-equal values may be ignored. 'nw_src_mask' and 'nw_dst_mask' must be
- * those that would be set for 'wildcards' by cls_rule_set_masks().
- *
- * The compared field is the one with wildcard bit or bits 'field_wc', offset
- * 'rule_ofs' within cls_rule's "fields" member, and length 'len', in bytes. */
-static inline bool ALWAYS_INLINE
-field_matches(const flow_t *a_, const flow_t *b_,
- uint32_t wildcards, uint32_t nw_src_mask, uint32_t nw_dst_mask,
- uint32_t field_wc, int ofs, int len)
-{
- /* This function is always inlined, and it is always called with 'field_wc'
- * as a compile-time constant, so the "if" conditionals here generate no
- * code. */
- const void *a = (const uint8_t *) a_ + ofs;
- const void *b = (const uint8_t *) b_ + ofs;
- if (!(field_wc & (field_wc - 1))) {
- /* Handle all the single-bit wildcard cases. */
- return wildcards & field_wc || equal_bytes(a, b, len);
- } else if (field_wc == OFPFW_NW_SRC_MASK ||
- field_wc == OFPFW_NW_DST_MASK) {
- uint32_t a_ip = read_uint32(a);
- uint32_t b_ip = read_uint32(b);
- uint32_t mask = (field_wc == OFPFW_NW_SRC_MASK
- ? nw_src_mask : nw_dst_mask);
- return ((a_ip ^ b_ip) & mask) == 0;
- } else {
- abort();
- }
-}
+ table = xzalloc(sizeof *table);
+ hmap_init(&table->rules);
+ minimask_clone(&table->mask, mask);
+ hmap_insert(&cls->tables, &table->hmap_node, minimask_hash(mask, 0));
-/* Returns true if 'a' and 'b' match, ignoring fields for which the wildcards
- * in 'wildcards' are set. 'nw_src_mask' and 'nw_dst_mask' must be those that
- * would be set for 'wildcards' by cls_rule_set_masks(). 'field_idx' is the
- * index of the first field to be compared; fields before 'field_idx' are
- * assumed to match. (Always returns true if 'field_idx' is CLS_N_FIELDS.) */
-static bool
-rules_match(const struct cls_rule *a, const struct cls_rule *b,
- uint32_t wildcards, uint32_t nw_src_mask, uint32_t nw_dst_mask,
- int field_idx)
-{
- /* This is related to Duff's device (see
- * http://en.wikipedia.org/wiki/Duff's_device). */
- switch (field_idx) {
-#define CLS_FIELD(WILDCARDS, MEMBER, NAME) \
- case CLS_F_IDX_##NAME: \
- if (!field_matches(&a->flow, &b->flow, \
- wildcards, nw_src_mask, nw_dst_mask, \
- WILDCARDS, offsetof(flow_t, MEMBER), \
- sizeof a->flow.MEMBER)) { \
- return false; \
- } \
- /* Fall though */
- CLS_FIELDS
-#undef CLS_FIELD
- }
- return true;
+ return table;
}
-/* Returns true if 'fixed' and 'wild' match. All fields in 'fixed' must have
- * fixed values; 'wild' may contain wildcards.
- *
- * 'field_idx' is the index of the first field to be compared; fields before
- * 'field_idx' are assumed to match. Always returns true if 'field_idx' is
- * CLS_N_FIELDS. */
-static bool
-rules_match_1wild(const struct cls_rule *fixed, const struct cls_rule *wild,
- int field_idx)
+static void
+destroy_table(struct classifier *cls, struct cls_table *table)
{
- return rules_match(fixed, wild, wild->wc.wildcards, wild->wc.nw_src_mask,
- wild->wc.nw_dst_mask, field_idx);
+ minimask_destroy(&table->mask);
+ hmap_remove(&cls->tables, &table->hmap_node);
+ hmap_destroy(&table->rules);
+ free(table);
}
-/* Returns true if 'wild1' and 'wild2' match, that is, if their fields
- * are equal modulo wildcards in 'wild1' or 'wild2'.
- *
- * 'field_idx' is the index of the first field to be compared; fields before
- * 'field_idx' are assumed to match. Always returns true if 'field_idx' is
- * CLS_N_FIELDS. */
-static bool
-rules_match_2wild(const struct cls_rule *wild1, const struct cls_rule *wild2,
- int field_idx)
+static struct cls_rule *
+find_match(const struct cls_table *table, const struct flow *flow)
{
- return rules_match(wild1, wild2,
- wild1->wc.wildcards | wild2->wc.wildcards,
- wild1->wc.nw_src_mask & wild2->wc.nw_src_mask,
- wild1->wc.nw_dst_mask & wild2->wc.nw_dst_mask,
- field_idx);
+ uint32_t hash = flow_hash_in_minimask(flow, &table->mask, 0);
+ struct cls_rule *rule;
+
+ HMAP_FOR_EACH_WITH_HASH (rule, hmap_node, hash, &table->rules) {
+ if (miniflow_equal_flow_in_minimask(&rule->match.flow, flow,
+ &table->mask)) {
+ return rule;
+ }
+ }
+
+ return NULL;
}
-/* Searches 'bucket' for a rule that matches 'target'. Returns the
- * highest-priority match, if one is found, or a null pointer if there is no
- * match.
- *
- * 'field_idx' must be the index of the first wildcarded field in 'bucket'. */
static struct cls_rule *
-search_bucket(struct cls_bucket *bucket, int field_idx,
- const struct cls_rule *target)
+find_equal(struct cls_table *table, const struct miniflow *flow, uint32_t hash)
{
- struct cls_rule *pos;
+ struct cls_rule *head;
- if (!equal_fields(&bucket->fixed, &target->flow, field_idx)) {
- return NULL;
- }
-
- LIST_FOR_EACH (pos, struct cls_rule, node.list, &bucket->rules) {
- if (rules_match_1wild(target, pos, field_idx)) {
- return pos;
+ HMAP_FOR_EACH_WITH_HASH (head, hmap_node, hash, &table->rules) {
+ if (miniflow_equal(&head->match.flow, flow)) {
+ return head;
}
}
return NULL;
}
-/* Searches 'table' for a rule that matches 'target'. Returns the
- * highest-priority match, if one is found, or a null pointer if there is no
- * match.
- *
- * 'field_idx' must be the index of the first wildcarded field in 'table'. */
static struct cls_rule *
-search_table(const struct hmap *table, int field_idx,
- const struct cls_rule *target)
+insert_rule(struct cls_table *table, struct cls_rule *new)
{
- struct cls_bucket *bucket;
+ struct cls_rule *head;
+
+ new->hmap_node.hash = miniflow_hash_in_minimask(&new->match.flow,
+ &new->match.mask, 0);
- switch (hmap_count(table)) {
- /* In these special cases there's no need to hash. */
- case 0:
+ head = find_equal(table, &new->match.flow, new->hmap_node.hash);
+ if (!head) {
+ hmap_insert(&table->rules, &new->hmap_node, new->hmap_node.hash);
+ list_init(&new->list);
return NULL;
- case 1:
- bucket = CONTAINER_OF(hmap_first(table), struct cls_bucket, hmap_node);
- return search_bucket(bucket, field_idx, target);
- }
+ } else {
+ /* Scan the list for the insertion point that will keep the list in
+ * order of decreasing priority. */
+ struct cls_rule *rule;
+ FOR_EACH_RULE_IN_LIST (rule, head) {
+ if (new->priority >= rule->priority) {
+ if (rule == head) {
+ /* 'new' is the new highest-priority flow in the list. */
+ hmap_replace(&table->rules,
+ &rule->hmap_node, &new->hmap_node);
+ }
- HMAP_FOR_EACH_WITH_HASH (bucket, struct cls_bucket, hmap_node,
- hash_fields(&target->flow, field_idx), table) {
- struct cls_rule *rule = search_bucket(bucket, field_idx, target);
- if (rule) {
- return rule;
+ if (new->priority == rule->priority) {
+ list_replace(&new->list, &rule->list);
+ return rule;
+ } else {
+ list_insert(&rule->list, &new->list);
+ return NULL;
+ }
+ }
}
+
+ /* Insert 'new' at the end of the list. */
+ list_push_back(&head->list, &new->list);
+ return NULL;
}
- return NULL;
}
static struct cls_rule *
-search_exact_table(const struct classifier *cls, size_t hash,
- const flow_t *target)
+next_rule_in_list__(struct cls_rule *rule)
{
- struct cls_rule *rule;
+ struct cls_rule *next = OBJECT_CONTAINING(rule->list.next, next, list);
+ return next;
+}
- HMAP_FOR_EACH_WITH_HASH (rule, struct cls_rule, node.hmap,
- hash, &cls->exact_table) {
- if (flow_equal(&rule->flow, target)) {
- return rule;
- }
- }
- return NULL;
+static struct cls_rule *
+next_rule_in_list(struct cls_rule *rule)
+{
+ struct cls_rule *next = next_rule_in_list__(rule);
+ return next->priority < rule->priority ? next : NULL;
}
projects / openvswitch / blobdiff