ipv4: coding style: comparison for equality with NULL

The ipv4 code uses a mixture of coding styles. In some instances check
for NULL pointer is done as x == NULL and sometimes as !x. !x is
preferred according to checkpatch and this patch makes the code
consistent by adopting the latter form.

No changes detected by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index c6473f3..0ee2168 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -585,7 +585,7 @@
 
 	ifm = nlmsg_data(nlh);
 	in_dev = inetdev_by_index(net, ifm->ifa_index);
-	if (in_dev == NULL) {
+	if (!in_dev) {
 		err = -ENODEV;
 		goto errout;
 	}
@@ -755,21 +755,21 @@
 
 	ifm = nlmsg_data(nlh);
 	err = -EINVAL;
-	if (ifm->ifa_prefixlen > 32 || tb[IFA_LOCAL] == NULL)
+	if (ifm->ifa_prefixlen > 32 || !tb[IFA_LOCAL])
 		goto errout;
 
 	dev = __dev_get_by_index(net, ifm->ifa_index);
 	err = -ENODEV;
-	if (dev == NULL)
+	if (!dev)
 		goto errout;
 
 	in_dev = __in_dev_get_rtnl(dev);
 	err = -ENOBUFS;
-	if (in_dev == NULL)
+	if (!in_dev)
 		goto errout;
 
 	ifa = inet_alloc_ifa();
-	if (ifa == NULL)
+	if (!ifa)
 		/*
 		 * A potential indev allocation can be left alive, it stays
 		 * assigned to its device and is destroy with it.
@@ -780,7 +780,7 @@
 	neigh_parms_data_state_setall(in_dev->arp_parms);
 	in_dev_hold(in_dev);
 
-	if (tb[IFA_ADDRESS] == NULL)
+	if (!tb[IFA_ADDRESS])
 		tb[IFA_ADDRESS] = tb[IFA_LOCAL];
 
 	INIT_HLIST_NODE(&ifa->hash);
@@ -1340,7 +1340,7 @@
 		if (named++ == 0)
 			goto skip;
 		dot = strchr(old, ':');
-		if (dot == NULL) {
+		if (!dot) {
 			sprintf(old, ":%d", named);
 			dot = old;
 		}
@@ -1509,7 +1509,7 @@
 	u32 preferred, valid;
 
 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*ifm), flags);
-	if (nlh == NULL)
+	if (!nlh)
 		return -EMSGSIZE;
 
 	ifm = nlmsg_data(nlh);
@@ -1628,7 +1628,7 @@
 
 	net = dev_net(ifa->ifa_dev->dev);
 	skb = nlmsg_new(inet_nlmsg_size(), GFP_KERNEL);
-	if (skb == NULL)
+	if (!skb)
 		goto errout;
 
 	err = inet_fill_ifaddr(skb, ifa, portid, seq, event, 0);
@@ -1665,7 +1665,7 @@
 		return -ENODATA;
 
 	nla = nla_reserve(skb, IFLA_INET_CONF, IPV4_DEVCONF_MAX * 4);
-	if (nla == NULL)
+	if (!nla)
 		return -EMSGSIZE;
 
 	for (i = 0; i < IPV4_DEVCONF_MAX; i++)
@@ -1754,7 +1754,7 @@
 
 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
 			flags);
-	if (nlh == NULL)
+	if (!nlh)
 		return -EMSGSIZE;
 
 	ncm = nlmsg_data(nlh);
@@ -1796,7 +1796,7 @@
 	int err = -ENOBUFS;
 
 	skb = nlmsg_new(inet_netconf_msgsize_devconf(type), GFP_ATOMIC);
-	if (skb == NULL)
+	if (!skb)
 		goto errout;
 
 	err = inet_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
@@ -1853,10 +1853,10 @@
 		break;
 	default:
 		dev = __dev_get_by_index(net, ifindex);
-		if (dev == NULL)
+		if (!dev)
 			goto errout;
 		in_dev = __in_dev_get_rtnl(dev);
-		if (in_dev == NULL)
+		if (!in_dev)
 			goto errout;
 		devconf = &in_dev->cnf;
 		break;
@@ -1864,7 +1864,7 @@
 
 	err = -ENOBUFS;
 	skb = nlmsg_new(inet_netconf_msgsize_devconf(-1), GFP_ATOMIC);
-	if (skb == NULL)
+	if (!skb)
 		goto errout;
 
 	err = inet_netconf_fill_devconf(skb, ifindex, devconf,
@@ -2215,7 +2215,7 @@
 {
 	struct devinet_sysctl_table *t = cnf->sysctl;
 
-	if (t == NULL)
+	if (!t)
 		return;
 
 	cnf->sysctl = NULL;
@@ -2276,16 +2276,16 @@
 
 	if (!net_eq(net, &init_net)) {
 		all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL);
-		if (all == NULL)
+		if (!all)
 			goto err_alloc_all;
 
 		dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
-		if (dflt == NULL)
+		if (!dflt)
 			goto err_alloc_dflt;
 
 #ifdef CONFIG_SYSCTL
 		tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
-		if (tbl == NULL)
+		if (!tbl)
 			goto err_alloc_ctl;
 
 		tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
@@ -2305,7 +2305,7 @@
 
 	err = -ENOMEM;
 	forw_hdr = register_net_sysctl(net, "net/ipv4", tbl);
-	if (forw_hdr == NULL)
+	if (!forw_hdr)
 		goto err_reg_ctl;
 	net->ipv4.forw_hdr = forw_hdr;
 #endif