drivers/net/team/team_mode_roundrobin.c

   1 /*
   2  * net/drivers/team/team_mode_roundrobin.c - Round-robin mode for team
   3  * Copyright (c) 2011 Jiri Pirko <jpirko@redhat.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/types.h>
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/errno.h>
  16 #include <linux/netdevice.h>
  17 #include <linux/if_team.h>
  18
  19 struct rr_priv {
  20         unsigned int sent_packets;
  21 };
  22
  23 static struct rr_priv *rr_priv(struct team *team)
  24 {
  25         return (struct rr_priv *) &team->mode_priv;
  26 }
  27
  28 static struct team_port *__get_first_port_up(struct team *team,
  29                                              struct team_port *port)
  30 {
  31         struct team_port *cur;
  32
  33         if (port->linkup)
  34                 return port;
  35         cur = port;
  36         list_for_each_entry_continue_rcu(cur, &team->port_list, list)
  37                 if (cur->linkup)
  38                         return cur;
  39         list_for_each_entry_rcu(cur, &team->port_list, list) {
  40                 if (cur == port)
  41                         break;
  42                 if (cur->linkup)
  43                         return cur;
  44         }
  45         return NULL;
  46 }
  47
  48 static bool rr_transmit(struct team *team, struct sk_buff *skb)
  49 {
  50         struct team_port *port;
  51         int port_index;
  52
  53         port_index = rr_priv(team)->sent_packets++ % team->port_count;
  54         port = team_get_port_by_index_rcu(team, port_index);
  55         if (unlikely(!port))
  56                 goto drop;
  57         port = __get_first_port_up(team, port);
  58         if (unlikely(!port))
  59                 goto drop;
  60         skb->dev = port->dev;
  61         if (dev_queue_xmit(skb))
  62                 return false;
  63         return true;
  64
  65 drop:
  66         dev_kfree_skb_any(skb);
  67         return false;
  68 }
  69
  70 static int rr_port_enter(struct team *team, struct team_port *port)
  71 {
  72         return team_port_set_team_mac(port);
  73 }
  74
  75 static void rr_port_change_mac(struct team *team, struct team_port *port)
  76 {
  77         team_port_set_team_mac(port);
  78 }
  79
  80 static const struct team_mode_ops rr_mode_ops = {
  81         .transmit               = rr_transmit,
  82         .port_enter             = rr_port_enter,
  83         .port_change_mac        = rr_port_change_mac,
  84 };
  85
  86 static struct team_mode rr_mode = {
  87         .kind           = "roundrobin",
  88         .owner          = THIS_MODULE,
  89         .priv_size      = sizeof(struct rr_priv),
  90         .ops            = &rr_mode_ops,
  91 };
  92
  93 static int __init rr_init_module(void)
  94 {
  95         return team_mode_register(&rr_mode);
  96 }
  97
  98 static void __exit rr_cleanup_module(void)
  99 {
 100         team_mode_unregister(&rr_mode);
 101 }
 102
 103 module_init(rr_init_module);
 104 module_exit(rr_cleanup_module);
 105
 106 MODULE_LICENSE("GPL v2");
 107 MODULE_AUTHOR("Jiri Pirko <jpirko@redhat.com>");
 108 MODULE_DESCRIPTION("Round-robin mode for team");
 109 MODULE_ALIAS("team-mode-roundrobin");