777 lines · 18.9 KB · C
RawDownload
/* * Copyright (c) 2007-2014 Nicira, Inc. * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA */ #include "flow.h"#include "datapath.h"#include "flow_netlink.h"#include <linux/uaccess.h>#include <linux/netdevice.h>#include <linux/etherdevice.h>#include <linux/if_ether.h>#include <linux/if_vlan.h>#include <net/llc_pdu.h>#include <linux/kernel.h>#include <linux/jhash.h>#include <linux/jiffies.h>#include <linux/llc.h>#include <linux/module.h>#include <linux/in.h>#include <linux/rcupdate.h>#include <linux/cpumask.h>#include <linux/if_arp.h>#include <linux/ip.h>#include <linux/ipv6.h>#include <linux/sctp.h>#include <linux/tcp.h>#include <linux/udp.h>#include <linux/icmp.h>#include <linux/icmpv6.h>#include <linux/rculist.h>#include <net/ip.h>#include <net/ipv6.h>#include <net/ndisc.h> #define TBL_MIN_BUCKETS		1024#define REHASH_INTERVAL		(10 * 60 * HZ) static struct kmem_cache *flow_cache;struct kmem_cache *flow_stats_cache __read_mostly; static u16 range_n_bytes(const struct sw_flow_key_range *range){	return range->end - range->start;} void ovs_flow_mask_key(struct sw_flow_key *dst, const struct sw_flow_key *src,		       bool full, const struct sw_flow_mask *mask){	int start = full ? 0 : mask->range.start;	int len = full ? sizeof *dst : range_n_bytes(&mask->range);	const long *m = (const long *)((const u8 *)&mask->key + start);	const long *s = (const long *)((const u8 *)src + start);	long *d = (long *)((u8 *)dst + start);	int i; 	/* If 'full' is true then all of 'dst' is fully initialized. Otherwise,	 * if 'full' is false the memory outside of the 'mask->range' is left	 * uninitialized. This can be used as an optimization when further	 * operations on 'dst' only use contents within 'mask->range'.	 */	for (i = 0; i < len; i += sizeof(long))		*d++ = *s++ & *m++;} struct sw_flow *ovs_flow_alloc(void){	struct sw_flow *flow;	struct flow_stats *stats; 	flow = kmem_cache_zalloc(flow_cache, GFP_KERNEL);	if (!flow)		return ERR_PTR(-ENOMEM); 	flow->stats_last_writer = -1; 	/* Initialize the default stat node. */	stats = kmem_cache_alloc_node(flow_stats_cache,				      GFP_KERNEL | __GFP_ZERO,				      node_online(0) ? 0 : NUMA_NO_NODE);	if (!stats)		goto err; 	spin_lock_init(&stats->lock); 	RCU_INIT_POINTER(flow->stats[0], stats); 	cpumask_set_cpu(0, &flow->cpu_used_mask); 	return flow;err:	kmem_cache_free(flow_cache, flow);	return ERR_PTR(-ENOMEM);} int ovs_flow_tbl_count(const struct flow_table *table){	return table->count;} static struct flex_array *alloc_buckets(unsigned int n_buckets){	struct flex_array *buckets;	int i, err; 	buckets = flex_array_alloc(sizeof(struct hlist_head),				   n_buckets, GFP_KERNEL);	if (!buckets)		return NULL; 	err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);	if (err) {		flex_array_free(buckets);		return NULL;	} 	for (i = 0; i < n_buckets; i++)		INIT_HLIST_HEAD((struct hlist_head *)					flex_array_get(buckets, i)); 	return buckets;} static void flow_free(struct sw_flow *flow){	int cpu; 	if (ovs_identifier_is_key(&flow->id))		kfree(flow->id.unmasked_key);	if (flow->sf_acts)		ovs_nla_free_flow_actions((struct sw_flow_actions __force *)flow->sf_acts);	/* We open code this to make sure cpu 0 is always considered */	for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, &flow->cpu_used_mask))		if (flow->stats[cpu])			kmem_cache_free(flow_stats_cache,					(struct flow_stats __force *)flow->stats[cpu]);	kmem_cache_free(flow_cache, flow);} static void rcu_free_flow_callback(struct rcu_head *rcu){	struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu); 	flow_free(flow);} void ovs_flow_free(struct sw_flow *flow, bool deferred){	if (!flow)		return; 	if (deferred)		call_rcu(&flow->rcu, rcu_free_flow_callback);	else		flow_free(flow);} static void free_buckets(struct flex_array *buckets){	flex_array_free(buckets);}  static void __table_instance_destroy(struct table_instance *ti){	free_buckets(ti->buckets);	kfree(ti);} static struct table_instance *table_instance_alloc(int new_size){	struct table_instance *ti = kmalloc(sizeof(*ti), GFP_KERNEL); 	if (!ti)		return NULL; 	ti->buckets = alloc_buckets(new_size); 	if (!ti->buckets) {		kfree(ti);		return NULL;	}	ti->n_buckets = new_size;	ti->node_ver = 0;	ti->keep_flows = false;	get_random_bytes(&ti->hash_seed, sizeof(u32)); 	return ti;} int ovs_flow_tbl_init(struct flow_table *table){	struct table_instance *ti, *ufid_ti; 	ti = table_instance_alloc(TBL_MIN_BUCKETS); 	if (!ti)		return -ENOMEM; 	ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS);	if (!ufid_ti)		goto free_ti; 	rcu_assign_pointer(table->ti, ti);	rcu_assign_pointer(table->ufid_ti, ufid_ti);	INIT_LIST_HEAD(&table->mask_list);	table->last_rehash = jiffies;	table->count = 0;	table->ufid_count = 0;	return 0; free_ti:	__table_instance_destroy(ti);	return -ENOMEM;} static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu){	struct table_instance *ti = container_of(rcu, struct table_instance, rcu); 	__table_instance_destroy(ti);} static void table_instance_destroy(struct table_instance *ti,				   struct table_instance *ufid_ti,				   bool deferred){	int i; 	if (!ti)		return; 	BUG_ON(!ufid_ti);	if (ti->keep_flows)		goto skip_flows; 	for (i = 0; i < ti->n_buckets; i++) {		struct sw_flow *flow;		struct hlist_head *head = flex_array_get(ti->buckets, i);		struct hlist_node *n;		int ver = ti->node_ver;		int ufid_ver = ufid_ti->node_ver; 		hlist_for_each_entry_safe(flow, n, head, flow_table.node[ver]) {			hlist_del_rcu(&flow->flow_table.node[ver]);			if (ovs_identifier_is_ufid(&flow->id))				hlist_del_rcu(&flow->ufid_table.node[ufid_ver]);			ovs_flow_free(flow, deferred);		}	} skip_flows:	if (deferred) {		call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb);		call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb);	} else {		__table_instance_destroy(ti);		__table_instance_destroy(ufid_ti);	}} /* No need for locking this function is called from RCU callback or * error path. */void ovs_flow_tbl_destroy(struct flow_table *table){	struct table_instance *ti = rcu_dereference_raw(table->ti);	struct table_instance *ufid_ti = rcu_dereference_raw(table->ufid_ti); 	table_instance_destroy(ti, ufid_ti, false);} struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti,				       u32 *bucket, u32 *last){	struct sw_flow *flow;	struct hlist_head *head;	int ver;	int i; 	ver = ti->node_ver;	while (*bucket < ti->n_buckets) {		i = 0;		head = flex_array_get(ti->buckets, *bucket);		hlist_for_each_entry_rcu(flow, head, flow_table.node[ver]) {			if (i < *last) {				i++;				continue;			}			*last = i + 1;			return flow;		}		(*bucket)++;		*last = 0;	} 	return NULL;} static struct hlist_head *find_bucket(struct table_instance *ti, u32 hash){	hash = jhash_1word(hash, ti->hash_seed);	return flex_array_get(ti->buckets,				(hash & (ti->n_buckets - 1)));} static void table_instance_insert(struct table_instance *ti,				  struct sw_flow *flow){	struct hlist_head *head; 	head = find_bucket(ti, flow->flow_table.hash);	hlist_add_head_rcu(&flow->flow_table.node[ti->node_ver], head);} static void ufid_table_instance_insert(struct table_instance *ti,				       struct sw_flow *flow){	struct hlist_head *head; 	head = find_bucket(ti, flow->ufid_table.hash);	hlist_add_head_rcu(&flow->ufid_table.node[ti->node_ver], head);} static void flow_table_copy_flows(struct table_instance *old,				  struct table_instance *new, bool ufid){	int old_ver;	int i; 	old_ver = old->node_ver;	new->node_ver = !old_ver; 	/* Insert in new table. */	for (i = 0; i < old->n_buckets; i++) {		struct sw_flow *flow;		struct hlist_head *head; 		head = flex_array_get(old->buckets, i); 		if (ufid)			hlist_for_each_entry(flow, head,					     ufid_table.node[old_ver])				ufid_table_instance_insert(new, flow);		else			hlist_for_each_entry(flow, head,					     flow_table.node[old_ver])				table_instance_insert(new, flow);	} 	old->keep_flows = true;} static struct table_instance *table_instance_rehash(struct table_instance *ti,						    int n_buckets, bool ufid){	struct table_instance *new_ti; 	new_ti = table_instance_alloc(n_buckets);	if (!new_ti)		return NULL; 	flow_table_copy_flows(ti, new_ti, ufid); 	return new_ti;} int ovs_flow_tbl_flush(struct flow_table *flow_table){	struct table_instance *old_ti, *new_ti;	struct table_instance *old_ufid_ti, *new_ufid_ti; 	new_ti = table_instance_alloc(TBL_MIN_BUCKETS);	if (!new_ti)		return -ENOMEM;	new_ufid_ti = table_instance_alloc(TBL_MIN_BUCKETS);	if (!new_ufid_ti)		goto err_free_ti; 	old_ti = ovsl_dereference(flow_table->ti);	old_ufid_ti = ovsl_dereference(flow_table->ufid_ti); 	rcu_assign_pointer(flow_table->ti, new_ti);	rcu_assign_pointer(flow_table->ufid_ti, new_ufid_ti);	flow_table->last_rehash = jiffies;	flow_table->count = 0;	flow_table->ufid_count = 0; 	table_instance_destroy(old_ti, old_ufid_ti, true);	return 0; err_free_ti:	__table_instance_destroy(new_ti);	return -ENOMEM;} static u32 flow_hash(const struct sw_flow_key *key,		     const struct sw_flow_key_range *range){	int key_start = range->start;	int key_end = range->end;	const u32 *hash_key = (const u32 *)((const u8 *)key + key_start);	int hash_u32s = (key_end - key_start) >> 2; 	/* Make sure number of hash bytes are multiple of u32. */	BUILD_BUG_ON(sizeof(long) % sizeof(u32)); 	return jhash2(hash_key, hash_u32s, 0);} static int flow_key_start(const struct sw_flow_key *key){	if (key->tun_proto)		return 0;	else		return rounddown(offsetof(struct sw_flow_key, phy),					  sizeof(long));} static bool cmp_key(const struct sw_flow_key *key1,		    const struct sw_flow_key *key2,		    int key_start, int key_end){	const long *cp1 = (const long *)((const u8 *)key1 + key_start);	const long *cp2 = (const long *)((const u8 *)key2 + key_start);	long diffs = 0;	int i; 	for (i = key_start; i < key_end;  i += sizeof(long))		diffs |= *cp1++ ^ *cp2++; 	return diffs == 0;} static bool flow_cmp_masked_key(const struct sw_flow *flow,				const struct sw_flow_key *key,				const struct sw_flow_key_range *range){	return cmp_key(&flow->key, key, range->start, range->end);} static bool ovs_flow_cmp_unmasked_key(const struct sw_flow *flow,				      const struct sw_flow_match *match){	struct sw_flow_key *key = match->key;	int key_start = flow_key_start(key);	int key_end = match->range.end; 	BUG_ON(ovs_identifier_is_ufid(&flow->id));	return cmp_key(flow->id.unmasked_key, key, key_start, key_end);} static struct sw_flow *masked_flow_lookup(struct table_instance *ti,					  const struct sw_flow_key *unmasked,					  const struct sw_flow_mask *mask){	struct sw_flow *flow;	struct hlist_head *head;	u32 hash;	struct sw_flow_key masked_key; 	ovs_flow_mask_key(&masked_key, unmasked, false, mask);	hash = flow_hash(&masked_key, &mask->range);	head = find_bucket(ti, hash);	hlist_for_each_entry_rcu(flow, head, flow_table.node[ti->node_ver]) {		if (flow->mask == mask && flow->flow_table.hash == hash &&		    flow_cmp_masked_key(flow, &masked_key, &mask->range))			return flow;	}	return NULL;} struct sw_flow *ovs_flow_tbl_lookup_stats(struct flow_table *tbl,				    const struct sw_flow_key *key,				    u32 *n_mask_hit){	struct table_instance *ti = rcu_dereference_ovsl(tbl->ti);	struct sw_flow_mask *mask;	struct sw_flow *flow; 	*n_mask_hit = 0;	list_for_each_entry_rcu(mask, &tbl->mask_list, list) {		(*n_mask_hit)++;		flow = masked_flow_lookup(ti, key, mask);		if (flow)  /* Found */			return flow;	}

Lines 1–500 of 777.