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authorDavid S. Miller <davem@sunset.davemloft.net>2007-06-10 17:22:39 -0700
committerDavid S. Miller <davem@sunset.davemloft.net>2007-07-10 22:05:57 -0700
commite06e7c615877026544ad7f8b309d1a3706410383 (patch)
treeeb087b49279e6db492039a5d684ca9acb13265a3 /net/ipv4/multipath_wrandom.c
parent4eb6bf6bfb580afaf1e1a1d30cba17a078530cf4 (diff)
[IPV4]: The scheduled removal of multipath cached routing support.
With help from Chris Wedgwood. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/multipath_wrandom.c')
-rw-r--r--net/ipv4/multipath_wrandom.c329
1 files changed, 0 insertions, 329 deletions
diff --git a/net/ipv4/multipath_wrandom.c b/net/ipv4/multipath_wrandom.c
deleted file mode 100644
index 57c50369453..00000000000
--- a/net/ipv4/multipath_wrandom.c
+++ /dev/null
@@ -1,329 +0,0 @@
-/*
- * Weighted random policy for multipath.
- *
- *
- * Version: $Id: multipath_wrandom.c,v 1.1.2.3 2004/09/22 07:51:40 elueck Exp $
- *
- * Authors: Einar Lueck <elueck@de.ibm.com><lkml@einar-lueck.de>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <asm/system.h>
-#include <asm/uaccess.h>
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <linux/timer.h>
-#include <linux/mm.h>
-#include <linux/kernel.h>
-#include <linux/fcntl.h>
-#include <linux/stat.h>
-#include <linux/socket.h>
-#include <linux/in.h>
-#include <linux/inet.h>
-#include <linux/netdevice.h>
-#include <linux/inetdevice.h>
-#include <linux/igmp.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include <linux/module.h>
-#include <linux/mroute.h>
-#include <linux/init.h>
-#include <linux/random.h>
-#include <net/ip.h>
-#include <net/protocol.h>
-#include <linux/skbuff.h>
-#include <net/sock.h>
-#include <net/icmp.h>
-#include <net/udp.h>
-#include <net/raw.h>
-#include <linux/notifier.h>
-#include <linux/if_arp.h>
-#include <linux/netfilter_ipv4.h>
-#include <net/ipip.h>
-#include <net/checksum.h>
-#include <net/ip_fib.h>
-#include <net/ip_mp_alg.h>
-
-#define MULTIPATH_STATE_SIZE 15
-
-struct multipath_candidate {
- struct multipath_candidate *next;
- int power;
- struct rtable *rt;
-};
-
-struct multipath_dest {
- struct list_head list;
-
- const struct fib_nh *nh_info;
- __be32 netmask;
- __be32 network;
- unsigned char prefixlen;
-
- struct rcu_head rcu;
-};
-
-struct multipath_bucket {
- struct list_head head;
- spinlock_t lock;
-};
-
-struct multipath_route {
- struct list_head list;
-
- int oif;
- __be32 gw;
- struct list_head dests;
-
- struct rcu_head rcu;
-};
-
-/* state: primarily weight per route information */
-static struct multipath_bucket state[MULTIPATH_STATE_SIZE];
-
-static unsigned char __multipath_lookup_weight(const struct flowi *fl,
- const struct rtable *rt)
-{
- const int state_idx = rt->idev->dev->ifindex % MULTIPATH_STATE_SIZE;
- struct multipath_route *r;
- struct multipath_route *target_route = NULL;
- struct multipath_dest *d;
- int weight = 1;
-
- /* lookup the weight information for a certain route */
- rcu_read_lock();
-
- /* find state entry for gateway or add one if necessary */
- list_for_each_entry_rcu(r, &state[state_idx].head, list) {
- if (r->gw == rt->rt_gateway &&
- r->oif == rt->idev->dev->ifindex) {
- target_route = r;
- break;
- }
- }
-
- if (!target_route) {
- /* this should not happen... but we are prepared */
- printk( KERN_CRIT"%s: missing state for gateway: %u and " \
- "device %d\n", __FUNCTION__, rt->rt_gateway,
- rt->idev->dev->ifindex);
- goto out;
- }
-
- /* find state entry for destination */
- list_for_each_entry_rcu(d, &target_route->dests, list) {
- __be32 targetnetwork = fl->fl4_dst &
- inet_make_mask(d->prefixlen);
-
- if ((targetnetwork & d->netmask) == d->network) {
- weight = d->nh_info->nh_weight;
- goto out;
- }
- }
-
-out:
- rcu_read_unlock();
- return weight;
-}
-
-static void wrandom_init_state(void)
-{
- int i;
-
- for (i = 0; i < MULTIPATH_STATE_SIZE; ++i) {
- INIT_LIST_HEAD(&state[i].head);
- spin_lock_init(&state[i].lock);
- }
-}
-
-static void wrandom_select_route(const struct flowi *flp,
- struct rtable *first,
- struct rtable **rp)
-{
- struct rtable *rt;
- struct rtable *decision;
- struct multipath_candidate *first_mpc = NULL;
- struct multipath_candidate *mpc, *last_mpc = NULL;
- int power = 0;
- int last_power;
- int selector;
- const size_t size_mpc = sizeof(struct multipath_candidate);
-
- /* collect all candidates and identify their weights */
- for (rt = rcu_dereference(first); rt;
- rt = rcu_dereference(rt->u.dst.rt_next)) {
- if ((rt->u.dst.flags & DST_BALANCED) != 0 &&
- multipath_comparekeys(&rt->fl, flp)) {
- struct multipath_candidate* mpc =
- (struct multipath_candidate*)
- kmalloc(size_mpc, GFP_ATOMIC);
-
- if (!mpc)
- return;
-
- power += __multipath_lookup_weight(flp, rt) * 10000;
-
- mpc->power = power;
- mpc->rt = rt;
- mpc->next = NULL;
-
- if (!first_mpc)
- first_mpc = mpc;
- else
- last_mpc->next = mpc;
-
- last_mpc = mpc;
- }
- }
-
- /* choose a weighted random candidate */
- decision = first;
- selector = random32() % power;
- last_power = 0;
-
- /* select candidate, adjust GC data and cleanup local state */
- decision = first;
- last_mpc = NULL;
- for (mpc = first_mpc; mpc; mpc = mpc->next) {
- mpc->rt->u.dst.lastuse = jiffies;
- if (last_power <= selector && selector < mpc->power)
- decision = mpc->rt;
-
- last_power = mpc->power;
- kfree(last_mpc);
- last_mpc = mpc;
- }
-
- /* concurrent __multipath_flush may lead to !last_mpc */
- kfree(last_mpc);
-
- decision->u.dst.__use++;
- *rp = decision;
-}
-
-static void wrandom_set_nhinfo(__be32 network,
- __be32 netmask,
- unsigned char prefixlen,
- const struct fib_nh *nh)
-{
- const int state_idx = nh->nh_oif % MULTIPATH_STATE_SIZE;
- struct multipath_route *r, *target_route = NULL;
- struct multipath_dest *d, *target_dest = NULL;
-
- /* store the weight information for a certain route */
- spin_lock_bh(&state[state_idx].lock);
-
- /* find state entry for gateway or add one if necessary */
- list_for_each_entry_rcu(r, &state[state_idx].head, list) {
- if (r->gw == nh->nh_gw && r->oif == nh->nh_oif) {
- target_route = r;
- break;
- }
- }
-
- if (!target_route) {
- const size_t size_rt = sizeof(struct multipath_route);
- target_route = (struct multipath_route *)
- kmalloc(size_rt, GFP_ATOMIC);
-
- target_route->gw = nh->nh_gw;
- target_route->oif = nh->nh_oif;
- memset(&target_route->rcu, 0, sizeof(struct rcu_head));
- INIT_LIST_HEAD(&target_route->dests);
-
- list_add_rcu(&target_route->list, &state[state_idx].head);
- }
-
- /* find state entry for destination or add one if necessary */
- list_for_each_entry_rcu(d, &target_route->dests, list) {
- if (d->nh_info == nh) {
- target_dest = d;
- break;
- }
- }
-
- if (!target_dest) {
- const size_t size_dst = sizeof(struct multipath_dest);
- target_dest = (struct multipath_dest*)
- kmalloc(size_dst, GFP_ATOMIC);
-
- target_dest->nh_info = nh;
- target_dest->network = network;
- target_dest->netmask = netmask;
- target_dest->prefixlen = prefixlen;
- memset(&target_dest->rcu, 0, sizeof(struct rcu_head));
-
- list_add_rcu(&target_dest->list, &target_route->dests);
- }
- /* else: we already stored this info for another destination =>
- * we are finished
- */
-
- spin_unlock_bh(&state[state_idx].lock);
-}
-
-static void __multipath_free(struct rcu_head *head)
-{
- struct multipath_route *rt = container_of(head, struct multipath_route,
- rcu);
- kfree(rt);
-}
-
-static void __multipath_free_dst(struct rcu_head *head)
-{
- struct multipath_dest *dst = container_of(head,
- struct multipath_dest,
- rcu);
- kfree(dst);
-}
-
-static void wrandom_flush(void)
-{
- int i;
-
- /* defere delete to all entries */
- for (i = 0; i < MULTIPATH_STATE_SIZE; ++i) {
- struct multipath_route *r;
-
- spin_lock_bh(&state[i].lock);
- list_for_each_entry_rcu(r, &state[i].head, list) {
- struct multipath_dest *d;
- list_for_each_entry_rcu(d, &r->dests, list) {
- list_del_rcu(&d->list);
- call_rcu(&d->rcu,
- __multipath_free_dst);
- }
- list_del_rcu(&r->list);
- call_rcu(&r->rcu,
- __multipath_free);
- }
-
- spin_unlock_bh(&state[i].lock);
- }
-}
-
-static struct ip_mp_alg_ops wrandom_ops = {
- .mp_alg_select_route = wrandom_select_route,
- .mp_alg_flush = wrandom_flush,
- .mp_alg_set_nhinfo = wrandom_set_nhinfo,
-};
-
-static int __init wrandom_init(void)
-{
- wrandom_init_state();
-
- return multipath_alg_register(&wrandom_ops, IP_MP_ALG_WRANDOM);
-}
-
-static void __exit wrandom_exit(void)
-{
- multipath_alg_unregister(&wrandom_ops, IP_MP_ALG_WRANDOM);
-}
-
-module_init(wrandom_init);
-module_exit(wrandom_exit);
-MODULE_LICENSE("GPL");