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>

1 files changed, 11 insertions, 10 deletions

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 2e69b8d16e68..bdc80734cd2c 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -565,7 +565,7 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb,
         opts->mss = tcp_advertise_mss(sk);
         remaining -= TCPOLEN_MSS_ALIGNED;
 
-        if (likely(sysctl_tcp_timestamps && *md5 == NULL)) {
+        if (likely(sysctl_tcp_timestamps && !*md5)) {
                 opts->options |= OPTION_TS;
                 opts->tsval = tcp_skb_timestamp(skb) + tp->tsoffset;
                 opts->tsecr = tp->rx_opt.ts_recent;
@@ -1148,7 +1148,7 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
 
         /* Get a new skb... force flag on. */
         buff = sk_stream_alloc_skb(sk, nsize, gfp);
-        if (buff == NULL)
+        if (!buff)
                 return -ENOMEM; /* We'll just try again later. */
 
         sk->sk_wmem_queued += buff->truesize;
@@ -1707,7 +1707,7 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len,
                 return tcp_fragment(sk, skb, len, mss_now, gfp);
 
         buff = sk_stream_alloc_skb(sk, 0, gfp);
-        if (unlikely(buff == NULL))
+        if (unlikely(!buff))
                 return -ENOMEM;
 
         sk->sk_wmem_queued += buff->truesize;
@@ -1925,7 +1925,8 @@ static int tcp_mtu_probe(struct sock *sk)
         }
 
         /* We're allowed to probe.  Build it now. */
-        if ((nskb = sk_stream_alloc_skb(sk, probe_size, GFP_ATOMIC)) == NULL)
+        nskb = sk_stream_alloc_skb(sk, probe_size, GFP_ATOMIC);
+        if (!nskb)
                 return -1;
         sk->sk_wmem_queued += nskb->truesize;
         sk_mem_charge(sk, nskb->truesize);
@@ -2733,7 +2734,7 @@ void tcp_xmit_retransmit_queue(struct sock *sk)
                 if (skb == tcp_send_head(sk))
                         break;
                 /* we could do better than to assign each time */
-                if (hole == NULL)
+                if (!hole)
                         tp->retransmit_skb_hint = skb;
 
                 /* Assume this retransmit will generate
@@ -2765,7 +2766,7 @@ begin_fwd:
                         goto begin_fwd;
 
                 } else if (!(sacked & TCPCB_LOST)) {
-                        if (hole == NULL && !(sacked & (TCPCB_SACKED_RETRANS|TCPCB_SACKED_ACKED)))
+                        if (!hole && !(sacked & (TCPCB_SACKED_RETRANS|TCPCB_SACKED_ACKED)))
                                 hole = skb;
                         continue;
 
@@ -2868,14 +2869,14 @@ int tcp_send_synack(struct sock *sk)
         struct sk_buff *skb;
 
         skb = tcp_write_queue_head(sk);
-        if (skb == NULL || !(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
+        if (!skb || !(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
                 pr_debug("%s: wrong queue state\n", __func__);
                 return -EFAULT;
         }
         if (!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_ACK)) {
                 if (skb_cloned(skb)) {
                         struct sk_buff *nskb = skb_copy(skb, GFP_ATOMIC);
-                        if (nskb == NULL)
+                        if (!nskb)
                                 return -ENOMEM;
                         tcp_unlink_write_queue(skb, sk);
                         __skb_header_release(nskb);
@@ -3300,7 +3301,7 @@ void tcp_send_ack(struct sock *sk)
          * sock.
          */
         buff = alloc_skb(MAX_TCP_HEADER, sk_gfp_atomic(sk, GFP_ATOMIC));
-        if (buff == NULL) {
+        if (!buff) {
                 inet_csk_schedule_ack(sk);
                 inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN;
                 inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
@@ -3344,7 +3345,7 @@ static int tcp_xmit_probe_skb(struct sock *sk, int urgent)
 
         /* We don't queue it, tcp_transmit_skb() sets ownership. */
         skb = alloc_skb(MAX_TCP_HEADER, sk_gfp_atomic(sk, GFP_ATOMIC));
-        if (skb == NULL)
+        if (!skb)
                 return -1;
 
         /* Reserve space for headers and set control bits. */