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-rw-r--r--net/ipv4/multipath_drr.c249
1 files changed, 0 insertions, 249 deletions
diff --git a/net/ipv4/multipath_drr.c b/net/ipv4/multipath_drr.c
deleted file mode 100644
index b03c5ca2c823..000000000000
--- a/net/ipv4/multipath_drr.c
+++ /dev/null
@@ -1,249 +0,0 @@
-/*
- * Device round robin policy for multipath.
- *
- *
- * Version: $Id: multipath_drr.c,v 1.1.2.1 2004/09/16 07:42:34 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 <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_mp_alg.h>
-
-struct multipath_device {
- int ifi; /* interface index of device */
- atomic_t usecount;
- int allocated;
-};
-
-#define MULTIPATH_MAX_DEVICECANDIDATES 10
-
-static struct multipath_device state[MULTIPATH_MAX_DEVICECANDIDATES];
-static DEFINE_SPINLOCK(state_lock);
-
-static int inline __multipath_findslot(void)
-{
- int i;
-
- for (i = 0; i < MULTIPATH_MAX_DEVICECANDIDATES; i++) {
- if (state[i].allocated == 0)
- return i;
- }
- return -1;
-}
-
-static int inline __multipath_finddev(int ifindex)
-{
- int i;
-
- for (i = 0; i < MULTIPATH_MAX_DEVICECANDIDATES; i++) {
- if (state[i].allocated != 0 &&
- state[i].ifi == ifindex)
- return i;
- }
- return -1;
-}
-
-static int drr_dev_event(struct notifier_block *this,
- unsigned long event, void *ptr)
-{
- struct net_device *dev = ptr;
- int devidx;
-
- switch (event) {
- case NETDEV_UNREGISTER:
- case NETDEV_DOWN:
- spin_lock_bh(&state_lock);
-
- devidx = __multipath_finddev(dev->ifindex);
- if (devidx != -1) {
- state[devidx].allocated = 0;
- state[devidx].ifi = 0;
- atomic_set(&state[devidx].usecount, 0);
- }
-
- spin_unlock_bh(&state_lock);
- break;
- }
-
- return NOTIFY_DONE;
-}
-
-static struct notifier_block drr_dev_notifier = {
- .notifier_call = drr_dev_event,
-};
-
-
-static void drr_safe_inc(atomic_t *usecount)
-{
- int n;
-
- atomic_inc(usecount);
-
- n = atomic_read(usecount);
- if (n <= 0) {
- int i;
-
- spin_lock_bh(&state_lock);
-
- for (i = 0; i < MULTIPATH_MAX_DEVICECANDIDATES; i++)
- atomic_set(&state[i].usecount, 0);
-
- spin_unlock_bh(&state_lock);
- }
-}
-
-static void drr_select_route(const struct flowi *flp,
- struct rtable *first, struct rtable **rp)
-{
- struct rtable *nh, *result, *cur_min;
- int min_usecount = -1;
- int devidx = -1;
- int cur_min_devidx = -1;
-
- /* 1. make sure all alt. nexthops have the same GC related data */
- /* 2. determine the new candidate to be returned */
- result = NULL;
- cur_min = NULL;
- for (nh = rcu_dereference(first); nh;
- nh = rcu_dereference(nh->u.dst.rt_next)) {
- if ((nh->u.dst.flags & DST_BALANCED) != 0 &&
- multipath_comparekeys(&nh->fl, flp)) {
- int nh_ifidx = nh->u.dst.dev->ifindex;
-
- nh->u.dst.lastuse = jiffies;
- nh->u.dst.__use++;
- if (result != NULL)
- continue;
-
- /* search for the output interface */
-
- /* this is not SMP safe, only add/remove are
- * SMP safe as wrong usecount updates have no big
- * impact
- */
- devidx = __multipath_finddev(nh_ifidx);
- if (devidx == -1) {
- /* add the interface to the array
- * SMP safe
- */
- spin_lock_bh(&state_lock);
-
- /* due to SMP: search again */
- devidx = __multipath_finddev(nh_ifidx);
- if (devidx == -1) {
- /* add entry for device */
- devidx = __multipath_findslot();
- if (devidx == -1) {
- /* unlikely but possible */
- continue;
- }
-
- state[devidx].allocated = 1;
- state[devidx].ifi = nh_ifidx;
- atomic_set(&state[devidx].usecount, 0);
- min_usecount = 0;
- }
-
- spin_unlock_bh(&state_lock);
- }
-
- if (min_usecount == 0) {
- /* if the device has not been used it is
- * the primary target
- */
- drr_safe_inc(&state[devidx].usecount);
- result = nh;
- } else {
- int count =
- atomic_read(&state[devidx].usecount);
-
- if (min_usecount == -1 ||
- count < min_usecount) {
- cur_min = nh;
- cur_min_devidx = devidx;
- min_usecount = count;
- }
- }
- }
- }
-
- if (!result) {
- if (cur_min) {
- drr_safe_inc(&state[cur_min_devidx].usecount);
- result = cur_min;
- } else {
- result = first;
- }
- }
-
- *rp = result;
-}
-
-static struct ip_mp_alg_ops drr_ops = {
- .mp_alg_select_route = drr_select_route,
-};
-
-static int __init drr_init(void)
-{
- int err = register_netdevice_notifier(&drr_dev_notifier);
-
- if (err)
- return err;
-
- err = multipath_alg_register(&drr_ops, IP_MP_ALG_DRR);
- if (err)
- goto fail;
-
- return 0;
-
-fail:
- unregister_netdevice_notifier(&drr_dev_notifier);
- return err;
-}
-
-static void __exit drr_exit(void)
-{
- unregister_netdevice_notifier(&drr_dev_notifier);
- multipath_alg_unregister(&drr_ops, IP_MP_ALG_DRR);
-}
-
-module_init(drr_init);
-module_exit(drr_exit);
-MODULE_LICENSE("GPL");