1 /* 2 * drivers/net/bond/bond_options.c - bonding options 3 * Copyright (c) 2013 Jiri Pirko <jiri@resnulli.us> 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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 12 13 #include <linux/errno.h> 14 #include <linux/if.h> 15 #include <linux/netdevice.h> 16 #include <linux/rwlock.h> 17 #include <linux/rcupdate.h> 18 #include "bonding.h" 19 20 static bool bond_mode_is_valid(int mode) 21 { 22 int i; 23 24 for (i = 0; bond_mode_tbl[i].modename; i++); 25 26 return mode >= 0 && mode < i; 27 } 28 29 int bond_option_mode_set(struct bonding *bond, int mode) 30 { 31 if (!bond_mode_is_valid(mode)) { 32 pr_err("invalid mode value %d.\n", mode); 33 return -EINVAL; 34 } 35 36 if (bond->dev->flags & IFF_UP) { 37 pr_err("%s: unable to update mode because interface is up.\n", 38 bond->dev->name); 39 return -EPERM; 40 } 41 42 if (bond_has_slaves(bond)) { 43 pr_err("%s: unable to update mode because bond has slaves.\n", 44 bond->dev->name); 45 return -EPERM; 46 } 47 48 if (BOND_MODE_IS_LB(mode) && bond->params.arp_interval) { 49 pr_err("%s: %s mode is incompatible with arp monitoring.\n", 50 bond->dev->name, bond_mode_tbl[mode].modename); 51 return -EINVAL; 52 } 53 54 /* don't cache arp_validate between modes */ 55 bond->params.arp_validate = BOND_ARP_VALIDATE_NONE; 56 bond->params.mode = mode; 57 return 0; 58 } 59 60 static struct net_device *__bond_option_active_slave_get(struct bonding *bond, 61 struct slave *slave) 62 { 63 return USES_PRIMARY(bond->params.mode) && slave ? slave->dev : NULL; 64 } 65 66 struct net_device *bond_option_active_slave_get_rcu(struct bonding *bond) 67 { 68 struct slave *slave = rcu_dereference(bond->curr_active_slave); 69 70 return __bond_option_active_slave_get(bond, slave); 71 } 72 73 struct net_device *bond_option_active_slave_get(struct bonding *bond) 74 { 75 return __bond_option_active_slave_get(bond, bond->curr_active_slave); 76 } 77 78 int bond_option_active_slave_set(struct bonding *bond, 79 struct net_device *slave_dev) 80 { 81 int ret = 0; 82 83 if (slave_dev) { 84 if (!netif_is_bond_slave(slave_dev)) { 85 pr_err("Device %s is not bonding slave.\n", 86 slave_dev->name); 87 return -EINVAL; 88 } 89 90 if (bond->dev != netdev_master_upper_dev_get(slave_dev)) { 91 pr_err("%s: Device %s is not our slave.\n", 92 bond->dev->name, slave_dev->name); 93 return -EINVAL; 94 } 95 } 96 97 if (!USES_PRIMARY(bond->params.mode)) { 98 pr_err("%s: Unable to change active slave; %s is in mode %d\n", 99 bond->dev->name, bond->dev->name, bond->params.mode); 100 return -EINVAL; 101 } 102 103 block_netpoll_tx(); 104 read_lock(&bond->lock); 105 write_lock_bh(&bond->curr_slave_lock); 106 107 /* check to see if we are clearing active */ 108 if (!slave_dev) { 109 pr_info("%s: Clearing current active slave.\n", 110 bond->dev->name); 111 rcu_assign_pointer(bond->curr_active_slave, NULL); 112 bond_select_active_slave(bond); 113 } else { 114 struct slave *old_active = bond->curr_active_slave; 115 struct slave *new_active = bond_slave_get_rtnl(slave_dev); 116 117 BUG_ON(!new_active); 118 119 if (new_active == old_active) { 120 /* do nothing */ 121 pr_info("%s: %s is already the current active slave.\n", 122 bond->dev->name, new_active->dev->name); 123 } else { 124 if (old_active && (new_active->link == BOND_LINK_UP) && 125 IS_UP(new_active->dev)) { 126 pr_info("%s: Setting %s as active slave.\n", 127 bond->dev->name, new_active->dev->name); 128 bond_change_active_slave(bond, new_active); 129 } else { 130 pr_err("%s: Could not set %s as active slave; either %s is down or the link is down.\n", 131 bond->dev->name, new_active->dev->name, 132 new_active->dev->name); 133 ret = -EINVAL; 134 } 135 } 136 } 137 138 write_unlock_bh(&bond->curr_slave_lock); 139 read_unlock(&bond->lock); 140 unblock_netpoll_tx(); 141 return ret; 142 } 143