Merge branch 'dev_get_by_index'

Ying Xue says:

====================
use appropriate APIs to get interfaces

Under rtnl_lock protection, we should use __dev_get_name/index()
rather than dev_get_name()/index() to find interface handlers
because the former interfaces can help us avoid to change interface
reference counter.

v2 changes:
 - Change return value of nl80211_set_wiphy() to 0 in patch #10
   by johannes's suggestion.
 - Add 'Acked-by' into several patches which were acknowledged by
   corresponding maintainers.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -3213,13 +3213,13 @@ 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 {
+		return -ENODEV;
+
 	pr_debug("slave_dev->name=%s:\n", slave_dev->name);
 	switch (cmd) {
 	case BOND_ENSLAVE_OLD:
@@ -3243,9 +3243,6 @@ static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd
 		res = -EOPNOTSUPP;
 	}
 
-		dev_put(slave_dev);
-	}
-
 	return res;
 }
 

drivers/net/eql.c

@@ -395,6 +395,7 @@ static int __eql_insert_slave(slave_queue_t *queue, slave_t *slave)
 		if (duplicate_slave)
 			eql_kill_one_slave(queue, duplicate_slave);
 
+		dev_hold(slave->dev);
 		list_add(&slave->list, &queue->all_slaves);
 		queue->num_slaves++;
 		slave->dev->flags |= IFF_SLAVE;
@@ -413,20 +414,19 @@ static int eql_enslave(struct net_device *master_dev, slaving_request_t __user *
 	if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
 		return -EFAULT;
 
-	slave_dev  = dev_get_by_name(&init_net, srq.slave_name);
-	if (slave_dev) {
+	slave_dev = __dev_get_by_name(&init_net, srq.slave_name);
+	if (!slave_dev)
+		return -ENODEV;
+
 	if ((master_dev->flags & IFF_UP) == IFF_UP) {
 		/* slave is not a master & not already a slave: */
-			if (!eql_is_master(slave_dev) &&
-			    !eql_is_slave(slave_dev)) {
+		if (!eql_is_master(slave_dev) && !eql_is_slave(slave_dev)) {
 			slave_t *s = kmalloc(sizeof(*s), GFP_KERNEL);
 			equalizer_t *eql = netdev_priv(master_dev);
 			int ret;
 
-				if (!s) {
-					dev_put(slave_dev);
+			if (!s)
 				return -ENOMEM;
-				}
 
 			memset(s, 0, sizeof(*s));
 			s->dev = slave_dev;
@@ -436,17 +436,14 @@ static int eql_enslave(struct net_device *master_dev, slaving_request_t __user *
 
 			spin_lock_bh(&eql->queue.lock);
 			ret = __eql_insert_slave(&eql->queue, s);
-				if (ret) {
-					dev_put(slave_dev);
+			if (ret)
 				kfree(s);
-				}
+
 			spin_unlock_bh(&eql->queue.lock);
 
 			return ret;
 		}
 	}
-		dev_put(slave_dev);
-	}
 
 	return -EINVAL;
 }
@@ -461,24 +458,20 @@ static int eql_emancipate(struct net_device *master_dev, slaving_request_t __use
 	if (copy_from_user(&srq, srqp, sizeof (slaving_request_t)))
 		return -EFAULT;
 
-	slave_dev = dev_get_by_name(&init_net, srq.slave_name);
+	slave_dev = __dev_get_by_name(&init_net, srq.slave_name);
+	if (!slave_dev)
+		return -ENODEV;
+
 	ret = -EINVAL;
-	if (slave_dev) {
 	spin_lock_bh(&eql->queue.lock);
-
 	if (eql_is_slave(slave_dev)) {
-			slave_t *slave = __eql_find_slave_dev(&eql->queue,
-							      slave_dev);
-
+		slave_t *slave = __eql_find_slave_dev(&eql->queue, slave_dev);
 		if (slave) {
 			eql_kill_one_slave(&eql->queue, slave);
 			ret = 0;
 		}
 	}
-		dev_put(slave_dev);
-
 	spin_unlock_bh(&eql->queue.lock);
-	}
 
 	return ret;
 }
@@ -494,7 +487,7 @@ static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
 	if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
 		return -EFAULT;
 
-	slave_dev = dev_get_by_name(&init_net, sc.slave_name);
+	slave_dev = __dev_get_by_name(&init_net, sc.slave_name);
 	if (!slave_dev)
 		return -ENODEV;
 
@@ -510,8 +503,6 @@ static int eql_g_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
 	}
 	spin_unlock_bh(&eql->queue.lock);
 
-	dev_put(slave_dev);
-
 	if (!ret && copy_to_user(scp, &sc, sizeof (slave_config_t)))
 		ret = -EFAULT;
 
@@ -529,7 +520,7 @@ static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
 	if (copy_from_user(&sc, scp, sizeof (slave_config_t)))
 		return -EFAULT;
 
-	slave_dev = dev_get_by_name(&init_net, sc.slave_name);
+	slave_dev = __dev_get_by_name(&init_net, sc.slave_name);
 	if (!slave_dev)
 		return -ENODEV;
 
@@ -548,8 +539,6 @@ static int eql_s_slave_cfg(struct net_device *dev, slave_config_t __user *scp)
 	}
 	spin_unlock_bh(&eql->queue.lock);
 
-	dev_put(slave_dev);
-
 	return ret;
 }
 

drivers/net/vxlan.c

@@ -741,10 +741,9 @@ static int vxlan_fdb_parse(struct nlattr *tb[], struct vxlan_dev *vxlan,
 		if (nla_len(tb[NDA_IFINDEX]) != sizeof(u32))
 			return -EINVAL;
 		*ifindex = nla_get_u32(tb[NDA_IFINDEX]);
-		tdev = dev_get_by_index(net, *ifindex);
+		tdev = __dev_get_by_index(net, *ifindex);
 		if (!tdev)
 			return -EADDRNOTAVAIL;
-		dev_put(tdev);
 	} else {
 		*ifindex = 0;
 	}

drivers/staging/cxt1e1/linux.c

@@ -770,9 +770,9 @@ do_del_chan (struct net_device *musycc_dev, void *data)
     if (cp.channum > 999)
         return -EINVAL;
     snprintf (buf, sizeof(buf), CHANNAME "%d", cp.channum);
-    if (!(dev = dev_get_by_name (&init_net, buf)))
-        return -ENOENT;
-    dev_put (dev);
+	dev = __dev_get_by_name(&init_net, buf);
+	if (!dev)
+		return -ENODEV;
     ret = do_deluser (dev, 1);
     if (ret)
         return ret;
@@ -792,7 +792,8 @@ do_reset (struct net_device *musycc_dev, void *data)
         char        buf[sizeof (CHANNAME) + 3];
 
         sprintf (buf, CHANNAME "%d", i);
-        if (!(ndev = dev_get_by_name(&init_net, buf)))
+	ndev = __dev_get_by_name(&init_net, buf);
+	if (!ndev)
 		continue;
         priv = dev_to_hdlc (ndev)->priv;
 
@@ -800,11 +801,9 @@ do_reset (struct net_device *musycc_dev, void *data)
             (unsigned long) (netdev_priv(musycc_dev)))
         {
             ndev->flags &= ~IFF_UP;
-            dev_put (ndev);
             netif_stop_queue (ndev);
             do_deluser (ndev, 1);
-        } else
-            dev_put (ndev);
+	}
     }
     return 0;
 }

net/batman-adv/hard-interface.c

@@ -87,15 +87,13 @@ static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
 		return false;
 
 	/* recurse over the parent device */
-	parent_dev = dev_get_by_index(&init_net, net_dev->iflink);
+	parent_dev = __dev_get_by_index(&init_net, net_dev->iflink);
 	/* if we got a NULL parent_dev there is something broken.. */
 	if (WARN(!parent_dev, "Cannot find parent device"))
 		return false;
 
 	ret = batadv_is_on_batman_iface(parent_dev);
 
-	if (parent_dev)
-		dev_put(parent_dev);
 	return ret;
 }
 

net/caif/chnl_net.c

@@ -285,7 +285,7 @@ static int chnl_net_open(struct net_device *dev)
 				goto error;
 		}
 
-		lldev = dev_get_by_index(dev_net(dev), llifindex);
+		lldev = __dev_get_by_index(dev_net(dev), llifindex);
 
 		if (lldev == NULL) {
 			pr_debug("no interface?\n");
@@ -307,7 +307,6 @@ static int chnl_net_open(struct net_device *dev)
 		mtu = min_t(int, dev->mtu, lldev->mtu - (headroom + tailroom));
 		mtu = min_t(int, GPRS_PDP_MTU, mtu);
 		dev_set_mtu(dev, mtu);
-		dev_put(lldev);
 
 		if (mtu < 100) {
 			pr_warn("CAIF Interface MTU too small (%d)\n", mtu);

net/can/gw.c

@@ -839,21 +839,21 @@ static int cgw_create_job(struct sk_buff *skb,  struct nlmsghdr *nlh)
 	if (!gwj->ccgw.src_idx || !gwj->ccgw.dst_idx)
 		goto out;
 
-	gwj->src.dev = dev_get_by_index(&init_net, gwj->ccgw.src_idx);
+	gwj->src.dev = __dev_get_by_index(&init_net, gwj->ccgw.src_idx);
 
 	if (!gwj->src.dev)
 		goto out;
 
 	if (gwj->src.dev->type != ARPHRD_CAN)
-		goto put_src_out;
+		goto out;
 
-	gwj->dst.dev = dev_get_by_index(&init_net, gwj->ccgw.dst_idx);
+	gwj->dst.dev = __dev_get_by_index(&init_net, gwj->ccgw.dst_idx);
 
 	if (!gwj->dst.dev)
-		goto put_src_out;
+		goto out;
 
 	if (gwj->dst.dev->type != ARPHRD_CAN)
-		goto put_src_dst_out;
+		goto out;
 
 	gwj->limit_hops = limhops;
 
@@ -862,11 +862,6 @@ static int cgw_create_job(struct sk_buff *skb,  struct nlmsghdr *nlh)
 	err = cgw_register_filter(gwj);
 	if (!err)
 		hlist_add_head_rcu(&gwj->list, &cgw_list);
-
-put_src_dst_out:
-	dev_put(gwj->dst.dev);
-put_src_out:
-	dev_put(gwj->src.dev);
 out:
 	if (err)
 		kmem_cache_free(cgw_cache, gwj);

net/dcb/dcbnl.c

@@ -1688,21 +1688,17 @@ static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
 	if (!tb[DCB_ATTR_IFNAME])
 		return -EINVAL;
 
-	netdev = dev_get_by_name(net, nla_data(tb[DCB_ATTR_IFNAME]));
+	netdev = __dev_get_by_name(net, nla_data(tb[DCB_ATTR_IFNAME]));
 	if (!netdev)
 		return -ENODEV;
 
-	if (!netdev->dcbnl_ops) {
-		ret = -EOPNOTSUPP;
-		goto out;
-	}
+	if (!netdev->dcbnl_ops)
+		return -EOPNOTSUPP;
 
 	reply_skb = dcbnl_newmsg(fn->type, dcb->cmd, portid, nlh->nlmsg_seq,
 				 nlh->nlmsg_flags, &reply_nlh);
-	if (!reply_skb) {
-		ret = -ENOBUFS;
-		goto out;
-	}
+	if (!reply_skb)
+		return -ENOBUFS;
 
 	ret = fn->cb(netdev, nlh, nlh->nlmsg_seq, tb, reply_skb);
 	if (ret < 0) {
@@ -1714,7 +1710,6 @@ static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh)
 
 	ret = rtnl_unicast(reply_skb, net, portid);
 out:
-	dev_put(netdev);
 	return ret;
 }
 

net/decnet/dn_route.c

@@ -1666,12 +1666,8 @@ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 
 	if (fld.flowidn_iif) {
 		struct net_device *dev;
-		if ((dev = dev_get_by_index(&init_net, fld.flowidn_iif)) == NULL) {
-			kfree_skb(skb);
-			return -ENODEV;
-		}
-		if (!dev->dn_ptr) {
-			dev_put(dev);
+		dev = __dev_get_by_index(&init_net, fld.flowidn_iif);
+		if (!dev || !dev->dn_ptr) {
 			kfree_skb(skb);
 			return -ENODEV;
 		}
@@ -1693,8 +1689,6 @@ static int dn_cache_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 		err = dn_route_output_key((struct dst_entry **)&rt, &fld, 0);
 	}
 
-	if (skb->dev)
-		dev_put(skb->dev);
 	skb->dev = NULL;
 	if (err)
 		goto out_free;

net/wireless/nl80211.c

@@ -165,7 +165,7 @@ __cfg80211_rdev_from_attrs(struct net *netns, struct nlattr **attrs)
 
 	if (attrs[NL80211_ATTR_IFINDEX]) {
 		int ifindex = nla_get_u32(attrs[NL80211_ATTR_IFINDEX]);
-		netdev = dev_get_by_index(netns, ifindex);
+		netdev = __dev_get_by_index(netns, ifindex);
 		if (netdev) {
 			if (netdev->ieee80211_ptr)
 				tmp = wiphy_to_dev(
@@ -173,8 +173,6 @@ __cfg80211_rdev_from_attrs(struct net *netns, struct nlattr **attrs)
 			else
 				tmp = NULL;
 
-			dev_put(netdev);
-
 			/* not wireless device -- return error */
 			if (!tmp)
 				return ERR_PTR(-EINVAL);
@@ -1656,7 +1654,7 @@ static int nl80211_dump_wiphy_parse(struct sk_buff *skb,
 		struct cfg80211_registered_device *rdev;
 		int ifidx = nla_get_u32(tb[NL80211_ATTR_IFINDEX]);
 
-		netdev = dev_get_by_index(sock_net(skb->sk), ifidx);
+		netdev = __dev_get_by_index(sock_net(skb->sk), ifidx);
 		if (!netdev)
 			return -ENODEV;
 		if (netdev->ieee80211_ptr) {
@@ -1664,7 +1662,6 @@ static int nl80211_dump_wiphy_parse(struct sk_buff *skb,
 				netdev->ieee80211_ptr->wiphy);
 			state->filter_wiphy = rdev->wiphy_idx;
 		}
-		dev_put(netdev);
 	}
 
 	return 0;
@@ -1987,7 +1984,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 	if (info->attrs[NL80211_ATTR_IFINDEX]) {
 		int ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
 
-		netdev = dev_get_by_index(genl_info_net(info), ifindex);
+		netdev = __dev_get_by_index(genl_info_net(info), ifindex);
 		if (netdev && netdev->ieee80211_ptr)
 			rdev = wiphy_to_dev(netdev->ieee80211_ptr->wiphy);
 		else
@@ -2015,32 +2012,24 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 			rdev, nla_data(info->attrs[NL80211_ATTR_WIPHY_NAME]));
 
 	if (result)
-		goto bad_res;
+		return result;
 
 	if (info->attrs[NL80211_ATTR_WIPHY_TXQ_PARAMS]) {
 		struct ieee80211_txq_params txq_params;
 		struct nlattr *tb[NL80211_TXQ_ATTR_MAX + 1];
 
-		if (!rdev->ops->set_txq_params) {
-			result = -EOPNOTSUPP;
-			goto bad_res;
-		}
+		if (!rdev->ops->set_txq_params)
+			return -EOPNOTSUPP;
 
-		if (!netdev) {
-			result = -EINVAL;
-			goto bad_res;
-		}
+		if (!netdev)
+			return -EINVAL;
 
 		if (netdev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP &&
-		    netdev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO) {
-			result = -EINVAL;
-			goto bad_res;
-		}
+		    netdev->ieee80211_ptr->iftype != NL80211_IFTYPE_P2P_GO)
+			return -EINVAL;
 
-		if (!netif_running(netdev)) {
-			result = -ENETDOWN;
-			goto bad_res;
-		}
+		if (!netif_running(netdev))
+			return -ENETDOWN;
 
 		nla_for_each_nested(nl_txq_params,
 				    info->attrs[NL80211_ATTR_WIPHY_TXQ_PARAMS],
@@ -2051,12 +2040,12 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 				  txq_params_policy);
 			result = parse_txq_params(tb, &txq_params);
 			if (result)
-				goto bad_res;
+				return result;
 
 			result = rdev_set_txq_params(rdev, netdev,
 						     &txq_params);
 			if (result)
-				goto bad_res;
+				return result;
 		}
 	}
 
@@ -2065,7 +2054,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 				nl80211_can_set_dev_channel(wdev) ? wdev : NULL,
 				info);
 		if (result)
-			goto bad_res;
+			return result;
 	}
 
 	if (info->attrs[NL80211_ATTR_WIPHY_TX_POWER_SETTING]) {
@@ -2076,19 +2065,15 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 		if (!(rdev->wiphy.features & NL80211_FEATURE_VIF_TXPOWER))
 			txp_wdev = NULL;
 
-		if (!rdev->ops->set_tx_power) {
-			result = -EOPNOTSUPP;
-			goto bad_res;
-		}
+		if (!rdev->ops->set_tx_power)
+			return -EOPNOTSUPP;
 
 		idx = NL80211_ATTR_WIPHY_TX_POWER_SETTING;
 		type = nla_get_u32(info->attrs[idx]);
 
 		if (!info->attrs[NL80211_ATTR_WIPHY_TX_POWER_LEVEL] &&
-		    (type != NL80211_TX_POWER_AUTOMATIC)) {
-			result = -EINVAL;
-			goto bad_res;
-		}
+		    (type != NL80211_TX_POWER_AUTOMATIC))
+			return -EINVAL;
 
 		if (type != NL80211_TX_POWER_AUTOMATIC) {
 			idx = NL80211_ATTR_WIPHY_TX_POWER_LEVEL;
@@ -2097,7 +2082,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 
 		result = rdev_set_tx_power(rdev, txp_wdev, type, mbm);
 		if (result)
-			goto bad_res;
+			return result;
 	}
 
 	if (info->attrs[NL80211_ATTR_WIPHY_ANTENNA_TX] &&
@@ -2105,10 +2090,8 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 		u32 tx_ant, rx_ant;
 		if ((!rdev->wiphy.available_antennas_tx &&
 		     !rdev->wiphy.available_antennas_rx) ||
-		    !rdev->ops->set_antenna) {
-			result = -EOPNOTSUPP;
-			goto bad_res;
-		}
+		    !rdev->ops->set_antenna)
+			return -EOPNOTSUPP;
 
 		tx_ant = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_ANTENNA_TX]);
 		rx_ant = nla_get_u32(info->attrs[NL80211_ATTR_WIPHY_ANTENNA_RX]);
@@ -2116,17 +2099,15 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 		/* reject antenna configurations which don't match the
 		 * available antenna masks, except for the "all" mask */
 		if ((~tx_ant && (tx_ant & ~rdev->wiphy.available_antennas_tx)) ||
-		    (~rx_ant && (rx_ant & ~rdev->wiphy.available_antennas_rx))) {
-			result = -EINVAL;
-			goto bad_res;
-		}
+		    (~rx_ant && (rx_ant & ~rdev->wiphy.available_antennas_rx)))
+			return -EINVAL;
 
 		tx_ant = tx_ant & rdev->wiphy.available_antennas_tx;
 		rx_ant = rx_ant & rdev->wiphy.available_antennas_rx;
 
 		result = rdev_set_antenna(rdev, tx_ant, rx_ant);
 		if (result)
-			goto bad_res;
+			return result;
 	}
 
 	changed = 0;
@@ -2134,30 +2115,27 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 	if (info->attrs[NL80211_ATTR_WIPHY_RETRY_SHORT]) {
 		retry_short = nla_get_u8(
 			info->attrs[NL80211_ATTR_WIPHY_RETRY_SHORT]);
-		if (retry_short == 0) {
-			result = -EINVAL;
-			goto bad_res;
-		}
+		if (retry_short == 0)
+			return -EINVAL;
+
 		changed |= WIPHY_PARAM_RETRY_SHORT;
 	}
 
 	if (info->attrs[NL80211_ATTR_WIPHY_RETRY_LONG]) {
 		retry_long = nla_get_u8(
 			info->attrs[NL80211_ATTR_WIPHY_RETRY_LONG]);
-		if (retry_long == 0) {
-			result = -EINVAL;
-			goto bad_res;
-		}
+		if (retry_long == 0)
+			return -EINVAL;
+
 		changed |= WIPHY_PARAM_RETRY_LONG;
 	}
 
 	if (info->attrs[NL80211_ATTR_WIPHY_FRAG_THRESHOLD]) {
 		frag_threshold = nla_get_u32(
 			info->attrs[NL80211_ATTR_WIPHY_FRAG_THRESHOLD]);
-		if (frag_threshold < 256) {
-			result = -EINVAL;
-			goto bad_res;
-		}
+		if (frag_threshold < 256)
+			return -EINVAL;
+
 		if (frag_threshold != (u32) -1) {
 			/*
 			 * Fragments (apart from the last one) are required to
@@ -2187,10 +2165,8 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 		u32 old_frag_threshold, old_rts_threshold;
 		u8 old_coverage_class;
 
-		if (!rdev->ops->set_wiphy_params) {
-			result = -EOPNOTSUPP;
-			goto bad_res;
-		}
+		if (!rdev->ops->set_wiphy_params)
+			return -EOPNOTSUPP;
 
 		old_retry_short = rdev->wiphy.retry_short;
 		old_retry_long = rdev->wiphy.retry_long;
@@ -2218,11 +2194,7 @@ static int nl80211_set_wiphy(struct sk_buff *skb, struct genl_info *info)
 			rdev->wiphy.coverage_class = old_coverage_class;
 		}
 	}
-
- bad_res:
-	if (netdev)
-		dev_put(netdev);
-	return result;
+	return 0;
 }
 
 static inline u64 wdev_id(struct wireless_dev *wdev)