rtnetlink: rtnl_setlink() and rtnl_getlink() changes

rtnl_getlink() & rtnl_setlink() run with RTNL held, we can use
__dev_get_by_index() and __dev_get_by_name() variants and avoid
dev_hold()/dev_put()

Adds to rtnl_getlink() the capability to find a device by its name,
not only by its index.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2009-10-21 10:59:31 +00:00 committed by David S. Miller
parent a61f802613
commit a3d1289126

View File

@ -910,9 +910,9 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
err = -EINVAL;
ifm = nlmsg_data(nlh);
if (ifm->ifi_index > 0)
dev = dev_get_by_index(net, ifm->ifi_index);
dev = __dev_get_by_index(net, ifm->ifi_index);
else if (tb[IFLA_IFNAME])
dev = dev_get_by_name(net, ifname);
dev = __dev_get_by_name(net, ifname);
else
goto errout;
@ -922,11 +922,9 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
}
if ((err = validate_linkmsg(dev, tb)) < 0)
goto errout_dev;
goto errout;
err = do_setlink(dev, ifm, tb, ifname, 0);
errout_dev:
dev_put(dev);
errout:
return err;
}
@ -1154,6 +1152,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
{
struct net *net = sock_net(skb->sk);
struct ifinfomsg *ifm;
char ifname[IFNAMSIZ];
struct nlattr *tb[IFLA_MAX+1];
struct net_device *dev = NULL;
struct sk_buff *nskb;
@ -1163,19 +1162,23 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
if (err < 0)
return err;
if (tb[IFLA_IFNAME])
nla_strlcpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
ifm = nlmsg_data(nlh);
if (ifm->ifi_index > 0) {
dev = dev_get_by_index(net, ifm->ifi_index);
if (dev == NULL)
return -ENODEV;
} else
if (ifm->ifi_index > 0)
dev = __dev_get_by_index(net, ifm->ifi_index);
else if (tb[IFLA_IFNAME])
dev = __dev_get_by_name(net, ifname);
else
return -EINVAL;
if (dev == NULL)
return -ENODEV;
nskb = nlmsg_new(if_nlmsg_size(dev), GFP_KERNEL);
if (nskb == NULL) {
err = -ENOBUFS;
goto errout;
}
if (nskb == NULL)
return -ENOBUFS;
err = rtnl_fill_ifinfo(nskb, dev, RTM_NEWLINK, NETLINK_CB(skb).pid,
nlh->nlmsg_seq, 0, 0);
@ -1183,11 +1186,8 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
/* -EMSGSIZE implies BUG in if_nlmsg_size */
WARN_ON(err == -EMSGSIZE);
kfree_skb(nskb);
goto errout;
}
} else
err = rtnl_unicast(nskb, net, NETLINK_CB(skb).pid);
errout:
dev_put(dev);
return err;
}