2 * Distributed under the terms of the GNU GPL version 2.
3 * Copyright (c) 2007, 2008 The Board of Trustees of The Leland
4 * Stanford Junior University
12 #include <linux/slab.h>
13 #include <linux/vmalloc.h>
15 #include <linux/highmem.h>
16 #include <asm/pgtable.h>
18 static void *kmem_alloc(size_t);
19 static void *kmem_zalloc(size_t);
20 static void kmem_free(void *, size_t);
22 struct sw_table_hash {
26 unsigned int bucket_mask; /* Number of buckets minus 1. */
27 struct sw_flow **buckets;
30 static struct sw_flow **find_bucket(struct sw_table *swt,
31 const struct sw_flow_key *key)
33 struct sw_table_hash *th = (struct sw_table_hash *) swt;
34 unsigned int crc = crc32_calculate(&th->crc32, key,
35 offsetof(struct sw_flow_key, wildcards));
36 return &th->buckets[crc & th->bucket_mask];
39 static struct sw_flow *table_hash_lookup(struct sw_table *swt,
40 const struct sw_flow_key *key)
42 struct sw_flow *flow = *find_bucket(swt, key);
43 return flow && flow_keys_equal(&flow->key, key) ? flow : NULL;
46 static int table_hash_insert(struct sw_table *swt, struct sw_flow *flow)
48 struct sw_table_hash *th = (struct sw_table_hash *) swt;
49 struct sw_flow **bucket;
52 if (flow->key.wildcards != 0)
55 bucket = find_bucket(swt, &flow->key);
56 if (*bucket == NULL) {
58 rcu_assign_pointer(*bucket, flow);
61 struct sw_flow *old_flow = *bucket;
62 if (flow_keys_equal(&old_flow->key, &flow->key)) {
63 rcu_assign_pointer(*bucket, flow);
64 flow_deferred_free(old_flow);
73 static int table_hash_modify(struct sw_table *swt,
74 const struct sw_flow_key *key, uint16_t priority, int strict,
75 const struct ofp_action_header *actions, size_t actions_len)
77 struct sw_table_hash *th = (struct sw_table_hash *) swt;
78 unsigned int count = 0;
80 if (key->wildcards == 0) {
81 struct sw_flow **bucket = find_bucket(swt, key);
82 struct sw_flow *flow = *bucket;
83 if (flow && flow_matches_desc(&flow->key, key, strict)
84 && (!strict || (flow->priority == priority))) {
85 flow_replace_acts(flow, actions, actions_len);
91 for (i = 0; i <= th->bucket_mask; i++) {
92 struct sw_flow **bucket = &th->buckets[i];
93 struct sw_flow *flow = *bucket;
94 if (flow && flow_matches_desc(&flow->key, key, strict)
95 && (!strict || (flow->priority == priority))) {
96 flow_replace_acts(flow, actions, actions_len);
104 /* Caller must update n_flows. */
105 static int do_delete(struct sw_flow **bucket, struct sw_flow *flow)
107 rcu_assign_pointer(*bucket, NULL);
108 flow_deferred_free(flow);
112 /* Returns number of deleted flows. We can ignore the priority
113 * argument, since all exact-match entries are the same (highest)
115 static int table_hash_delete(struct sw_table *swt,
116 const struct sw_flow_key *key, uint16_t out_port,
117 uint16_t priority, int strict)
119 struct sw_table_hash *th = (struct sw_table_hash *) swt;
120 unsigned int count = 0;
122 if (key->wildcards == 0) {
123 struct sw_flow **bucket = find_bucket(swt, key);
124 struct sw_flow *flow = *bucket;
125 if (flow && flow_keys_equal(&flow->key, key)
126 && flow_has_out_port(flow, out_port))
127 count = do_delete(bucket, flow);
131 for (i = 0; i <= th->bucket_mask; i++) {
132 struct sw_flow **bucket = &th->buckets[i];
133 struct sw_flow *flow = *bucket;
134 if (flow && flow_matches_desc(&flow->key, key, strict)
135 && flow_has_out_port(flow, out_port))
136 count += do_delete(bucket, flow);
139 th->n_flows -= count;
143 static int table_hash_timeout(struct datapath *dp, struct sw_table *swt)
145 struct sw_table_hash *th = (struct sw_table_hash *) swt;
149 mutex_lock(&dp_mutex);
150 for (i = 0; i <= th->bucket_mask; i++) {
151 struct sw_flow **bucket = &th->buckets[i];
152 struct sw_flow *flow = *bucket;
154 int reason = flow_timeout(flow);
156 count += do_delete(bucket, flow);
157 dp_send_flow_expired(dp, flow, reason);
161 th->n_flows -= count;
162 mutex_unlock(&dp_mutex);
167 static void table_hash_destroy(struct sw_table *swt)
169 struct sw_table_hash *th = (struct sw_table_hash *) swt;
171 for (i = 0; i <= th->bucket_mask; i++)
173 flow_free(th->buckets[i]);
174 kmem_free(th->buckets, (th->bucket_mask + 1) * sizeof *th->buckets);
178 static int table_hash_iterate(struct sw_table *swt,
179 const struct sw_flow_key *key, uint16_t out_port,
180 struct sw_table_position *position,
181 int (*callback)(struct sw_flow *, void *private),
184 struct sw_table_hash *th = (struct sw_table_hash *) swt;
186 if (position->private[0] > th->bucket_mask)
189 if (key->wildcards == 0) {
190 struct sw_flow *flow;
193 flow = table_hash_lookup(swt, key);
194 if (!flow || !flow_has_out_port(flow, out_port))
197 error = callback(flow, private);
199 position->private[0] = -1;
204 for (i = position->private[0]; i <= th->bucket_mask; i++) {
205 struct sw_flow *flow = th->buckets[i];
206 if (flow && flow_matches_1wild(&flow->key, key)
207 && flow_has_out_port(flow, out_port)) {
208 int error = callback(flow, private);
210 position->private[0] = i;
218 static void table_hash_stats(struct sw_table *swt,
219 struct sw_table_stats *stats)
221 struct sw_table_hash *th = (struct sw_table_hash *) swt;
222 stats->name = "hash";
223 stats->wildcards = 0; /* No wildcards are supported. */
224 stats->n_flows = th->n_flows;
225 stats->max_flows = th->bucket_mask + 1;
226 stats->n_lookup = swt->n_lookup;
227 stats->n_matched = swt->n_matched;
230 struct sw_table *table_hash_create(unsigned int polynomial,
231 unsigned int n_buckets)
233 struct sw_table_hash *th;
234 struct sw_table *swt;
236 th = kzalloc(sizeof *th, GFP_KERNEL);
240 BUG_ON(n_buckets & (n_buckets - 1));
241 th->buckets = kmem_zalloc(n_buckets * sizeof *th->buckets);
242 if (th->buckets == NULL) {
243 printk("failed to allocate %u buckets\n", n_buckets);
247 th->bucket_mask = n_buckets - 1;
250 swt->lookup = table_hash_lookup;
251 swt->insert = table_hash_insert;
252 swt->delete = table_hash_delete;
253 swt->timeout = table_hash_timeout;
254 swt->destroy = table_hash_destroy;
255 swt->iterate = table_hash_iterate;
256 swt->stats = table_hash_stats;
258 crc32_init(&th->crc32, polynomial);
264 /* Double-hashing table. */
266 struct sw_table_hash2 {
268 struct sw_table *subtable[2];
271 static struct sw_flow *table_hash2_lookup(struct sw_table *swt,
272 const struct sw_flow_key *key)
274 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
277 for (i = 0; i < 2; i++) {
278 struct sw_flow *flow = *find_bucket(t2->subtable[i], key);
279 if (flow && flow_keys_equal(&flow->key, key))
285 static int table_hash2_insert(struct sw_table *swt, struct sw_flow *flow)
287 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
289 if (table_hash_insert(t2->subtable[0], flow))
291 return table_hash_insert(t2->subtable[1], flow);
294 static int table_hash2_modify(struct sw_table *swt,
295 const struct sw_flow_key *key, uint16_t priority, int strict,
296 const struct ofp_action_header *actions, size_t actions_len)
298 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
299 return (table_hash_modify(t2->subtable[0], key, priority, strict,
300 actions, actions_len)
301 + table_hash_modify(t2->subtable[1], key, priority, strict,
302 actions, actions_len));
305 static int table_hash2_delete(struct sw_table *swt,
306 const struct sw_flow_key *key,
308 uint16_t priority, int strict)
310 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
311 return (table_hash_delete(t2->subtable[0], key, out_port, priority, strict)
312 + table_hash_delete(t2->subtable[1], key, out_port,
316 static int table_hash2_timeout(struct datapath *dp, struct sw_table *swt)
318 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
319 return (table_hash_timeout(dp, t2->subtable[0])
320 + table_hash_timeout(dp, t2->subtable[1]));
323 static void table_hash2_destroy(struct sw_table *swt)
325 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
326 table_hash_destroy(t2->subtable[0]);
327 table_hash_destroy(t2->subtable[1]);
331 static int table_hash2_iterate(struct sw_table *swt,
332 const struct sw_flow_key *key, uint16_t out_port,
333 struct sw_table_position *position,
334 int (*callback)(struct sw_flow *, void *),
337 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
340 for (i = position->private[1]; i < 2; i++) {
341 int error = table_hash_iterate(t2->subtable[i], key, out_port,
342 position, callback, private);
346 position->private[0] = 0;
347 position->private[1]++;
352 static void table_hash2_stats(struct sw_table *swt,
353 struct sw_table_stats *stats)
355 struct sw_table_hash2 *t2 = (struct sw_table_hash2 *) swt;
356 struct sw_table_stats substats[2];
359 for (i = 0; i < 2; i++)
360 table_hash_stats(t2->subtable[i], &substats[i]);
361 stats->name = "hash2";
362 stats->wildcards = 0; /* No wildcards are supported. */
363 stats->n_flows = substats[0].n_flows + substats[1].n_flows;
364 stats->max_flows = substats[0].max_flows + substats[1].max_flows;
365 stats->n_lookup = swt->n_lookup;
366 stats->n_matched = swt->n_matched;
369 struct sw_table *table_hash2_create(unsigned int poly0, unsigned int buckets0,
370 unsigned int poly1, unsigned int buckets1)
373 struct sw_table_hash2 *t2;
374 struct sw_table *swt;
376 t2 = kzalloc(sizeof *t2, GFP_KERNEL);
380 t2->subtable[0] = table_hash_create(poly0, buckets0);
381 if (t2->subtable[0] == NULL)
384 t2->subtable[1] = table_hash_create(poly1, buckets1);
385 if (t2->subtable[1] == NULL)
386 goto out_free_subtable0;
389 swt->lookup = table_hash2_lookup;
390 swt->insert = table_hash2_insert;
391 swt->modify = table_hash2_modify;
392 swt->delete = table_hash2_delete;
393 swt->timeout = table_hash2_timeout;
394 swt->destroy = table_hash2_destroy;
395 swt->iterate = table_hash2_iterate;
396 swt->stats = table_hash2_stats;
401 table_hash_destroy(t2->subtable[0]);
407 /* From fs/xfs/linux-2.4/kmem.c. */
410 kmem_alloc(size_t size)
414 #ifdef KMALLOC_MAX_SIZE
415 if (size > KMALLOC_MAX_SIZE)
418 ptr = kmalloc(size, GFP_KERNEL);
422 printk("openflow: used vmalloc for %lu bytes\n",
423 (unsigned long)size);
429 kmem_zalloc(size_t size)
431 void *ptr = kmem_alloc(size);
433 memset(ptr, 0, size);
438 kmem_free(void *ptr, size_t size)
440 if (((unsigned long)ptr < VMALLOC_START) ||
441 ((unsigned long)ptr >= VMALLOC_END)) {