bonding: use __dev_get_by_name instead of dev_get_by_name to find interface

The following call chain indicates that bond_do_ioctl() is protected
under rtnl_lock. If we use __dev_get_by_name() instead of
dev_get_by_name() to find interface handler in it, this would
help us avoid to change reference counter of interface once.

dev_ioctl()
  rtnl_lock()
  dev_ifsioc()
    bond_do_ioctl()
  rtnl_unlock()

Additionally we also change the coding style in bond_do_ioctl(),
letting it more readable for us.

Cc: Jay Vosburgh <fubar@us.ibm.com>
Cc: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ying Xue 2014-01-15 10:23:37 +08:00 committed by David S. Miller
parent bdffbb8e26
commit 0917b9334b
1 changed files with 23 additions and 26 deletions

View File

@ -3213,37 +3213,34 @@ static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
return -EPERM;
slave_dev = dev_get_by_name(net, ifr->ifr_slave);
slave_dev = __dev_get_by_name(net, ifr->ifr_slave);
pr_debug("slave_dev=%p:\n", slave_dev);
if (!slave_dev)
res = -ENODEV;
else {
pr_debug("slave_dev->name=%s:\n", slave_dev->name);
switch (cmd) {
case BOND_ENSLAVE_OLD:
case SIOCBONDENSLAVE:
res = bond_enslave(bond_dev, slave_dev);
break;
case BOND_RELEASE_OLD:
case SIOCBONDRELEASE:
res = bond_release(bond_dev, slave_dev);
break;
case BOND_SETHWADDR_OLD:
case SIOCBONDSETHWADDR:
bond_set_dev_addr(bond_dev, slave_dev);
res = 0;
break;
case BOND_CHANGE_ACTIVE_OLD:
case SIOCBONDCHANGEACTIVE:
res = bond_option_active_slave_set(bond, slave_dev);
break;
default:
res = -EOPNOTSUPP;
}
return -ENODEV;
dev_put(slave_dev);
pr_debug("slave_dev->name=%s:\n", slave_dev->name);
switch (cmd) {
case BOND_ENSLAVE_OLD:
case SIOCBONDENSLAVE:
res = bond_enslave(bond_dev, slave_dev);
break;
case BOND_RELEASE_OLD:
case SIOCBONDRELEASE:
res = bond_release(bond_dev, slave_dev);
break;
case BOND_SETHWADDR_OLD:
case SIOCBONDSETHWADDR:
bond_set_dev_addr(bond_dev, slave_dev);
res = 0;
break;
case BOND_CHANGE_ACTIVE_OLD:
case SIOCBONDCHANGEACTIVE:
res = bond_option_active_slave_set(bond, slave_dev);
break;
default:
res = -EOPNOTSUPP;
}
return res;