net: Convert LIMIT_NETDEBUG to net_dbg_ratelimited

Use the more common dynamic_debug capable net_dbg_ratelimited
and remove the LIMIT_NETDEBUG macro.

All messages are still ratelimited.

Some KERN_<LEVEL> uses are changed to KERN_DEBUG.

This may have some negative impact on messages that were
emitted at KERN_INFO that are not not enabled at all unless
DEBUG is defined or dynamic_debug is enabled.  Even so,
these messages are now _not_ emitted by default.

This also eliminates the use of the net_msg_warn sysctl
"/proc/sys/net/core/warnings".  For backward compatibility,
the sysctl is not removed, but it has no function.  The extern
declaration of net_msg_warn is removed from sock.h and made
static in net/core/sysctl_net_core.c

Miscellanea:

o Update the sysctl documentation
o Remove the embedded uses of pr_fmt
o Coalesce format fragments
o Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 35 insertions, 34 deletions

diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 5882f584910e..36b7bfa609d6 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -784,8 +784,8 @@ static void icmp_unreach(struct sk_buff *skb)
 			 */
 			switch (net->ipv4.sysctl_ip_no_pmtu_disc) {
 			default:
-				LIMIT_NETDEBUG(KERN_INFO pr_fmt("%pI4: fragmentation needed and DF set\n"),
-					       &iph->daddr);
+				net_dbg_ratelimited("%pI4: fragmentation needed and DF set\n",
+						    &iph->daddr);
 				break;
 			case 2:
 				goto out;
@@ -798,8 +798,8 @@ static void icmp_unreach(struct sk_buff *skb)
 			}
 			break;
 		case ICMP_SR_FAILED:
-			LIMIT_NETDEBUG(KERN_INFO pr_fmt("%pI4: Source Route Failed\n"),
-				       &iph->daddr);
+			net_dbg_ratelimited("%pI4: Source Route Failed\n",
+					    &iph->daddr);
 			break;
 		default:
 			break;
diff --git a/net/ipv4/inet_fragment.c b/net/ipv4/inet_fragment.c
index 19419b60cb37..e7920352646a 100644
--- a/net/ipv4/inet_fragment.c
+++ b/net/ipv4/inet_fragment.c
@@ -458,6 +458,6 @@ void inet_frag_maybe_warn_overflow(struct inet_frag_queue *q,
 		". Dropping fragment.\n";
 
 	if (PTR_ERR(q) == -ENOBUFS)
-		LIMIT_NETDEBUG(KERN_WARNING "%s%s", prefix, msg);
+		net_dbg_ratelimited("%s%s", prefix, msg);
 }
 EXPORT_SYMBOL(inet_frag_maybe_warn_overflow);
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 4d964dadd655..e5b6d0ddcb58 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -618,8 +618,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *prev,
 	return 0;
 
 out_nomem:
-	LIMIT_NETDEBUG(KERN_ERR pr_fmt("queue_glue: no memory for gluing queue %p\n"),
-		       qp);
+	net_dbg_ratelimited("queue_glue: no memory for gluing queue %p\n", qp);
 	err = -ENOMEM;
 	goto out_fail;
 out_oversize:
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 5f979c7f5135..d91436ba17ea 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5854,12 +5854,12 @@ static inline void pr_drop_req(struct request_sock *req, __u16 port, int family)
 	struct inet_request_sock *ireq = inet_rsk(req);
 
 	if (family == AF_INET)
-		LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("drop open request from %pI4/%u\n"),
-			       &ireq->ir_rmt_addr, port);
+		net_dbg_ratelimited("drop open request from %pI4/%u\n",
+				    &ireq->ir_rmt_addr, port);
 #if IS_ENABLED(CONFIG_IPV6)
 	else if (family == AF_INET6)
-		LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("drop open request from %pI6/%u\n"),
-			       &ireq->ir_v6_rmt_addr, port);
+		net_dbg_ratelimited("drop open request from %pI6/%u\n",
+				    &ireq->ir_v6_rmt_addr, port);
 #endif
 }
 
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 9b21ae8b2e31..1829c7fbc77e 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -374,17 +374,19 @@ void tcp_retransmit_timer(struct sock *sk)
 		 */
 		struct inet_sock *inet = inet_sk(sk);
 		if (sk->sk_family == AF_INET) {
-			LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("Peer %pI4:%u/%u unexpectedly shrunk window %u:%u (repaired)\n"),
-				       &inet->inet_daddr,
-				       ntohs(inet->inet_dport), inet->inet_num,
-				       tp->snd_una, tp->snd_nxt);
+			net_dbg_ratelimited("Peer %pI4:%u/%u unexpectedly shrunk window %u:%u (repaired)\n",
+					    &inet->inet_daddr,
+					    ntohs(inet->inet_dport),
+					    inet->inet_num,
+					    tp->snd_una, tp->snd_nxt);
 		}
 #if IS_ENABLED(CONFIG_IPV6)
 		else if (sk->sk_family == AF_INET6) {
-			LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("Peer %pI6:%u/%u unexpectedly shrunk window %u:%u (repaired)\n"),
-				       &sk->sk_v6_daddr,
-				       ntohs(inet->inet_dport), inet->inet_num,
-				       tp->snd_una, tp->snd_nxt);
+			net_dbg_ratelimited("Peer %pI6:%u/%u unexpectedly shrunk window %u:%u (repaired)\n",
+					    &sk->sk_v6_daddr,
+					    ntohs(inet->inet_dport),
+					    inet->inet_num,
+					    tp->snd_una, tp->snd_nxt);
 		}
 #endif
 		if (tcp_time_stamp - tp->rcv_tstamp > TCP_RTO_MAX) {
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index d13751685f44..1b6e9d5fadef 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1051,7 +1051,7 @@ back_from_confirm:
 		/* ... which is an evident application bug. --ANK */
 		release_sock(sk);
 
-		LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("cork app bug 2\n"));
+		net_dbg_ratelimited("cork app bug 2\n");
 		err = -EINVAL;
 		goto out;
 	}
@@ -1133,7 +1133,7 @@ int udp_sendpage(struct sock *sk, struct page *page, int offset,
 	if (unlikely(!up->pending)) {
 		release_sock(sk);
 
-		LIMIT_NETDEBUG(KERN_DEBUG pr_fmt("udp cork app bug 3\n"));
+		net_dbg_ratelimited("udp cork app bug 3\n");
 		return -EINVAL;
 	}
 
@@ -1547,8 +1547,8 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 		 * provided by the application."
 		 */
 		if (up->pcrlen == 0) {          /* full coverage was set  */
-			LIMIT_NETDEBUG(KERN_WARNING "UDPLite: partial coverage %d while full coverage %d requested\n",
-				       UDP_SKB_CB(skb)->cscov, skb->len);
+			net_dbg_ratelimited("UDPLite: partial coverage %d while full coverage %d requested\n",
+					    UDP_SKB_CB(skb)->cscov, skb->len);
 			goto drop;
 		}
 		/* The next case involves violating the min. coverage requested
@@ -1558,8 +1558,8 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 		 * Therefore the above ...()->partial_cov statement is essential.
 		 */
 		if (UDP_SKB_CB(skb)->cscov  <  up->pcrlen) {
-			LIMIT_NETDEBUG(KERN_WARNING "UDPLite: coverage %d too small, need min %d\n",
-				       UDP_SKB_CB(skb)->cscov, up->pcrlen);
+			net_dbg_ratelimited("UDPLite: coverage %d too small, need min %d\n",
+					    UDP_SKB_CB(skb)->cscov, up->pcrlen);
 			goto drop;
 		}
 	}
@@ -1828,11 +1828,11 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
 	return 0;
 
 short_packet:
-	LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n",
-		       proto == IPPROTO_UDPLITE ? "Lite" : "",
-		       &saddr, ntohs(uh->source),
-		       ulen, skb->len,
-		       &daddr, ntohs(uh->dest));
+	net_dbg_ratelimited("UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n",
+			    proto == IPPROTO_UDPLITE ? "Lite" : "",
+			    &saddr, ntohs(uh->source),
+			    ulen, skb->len,
+			    &daddr, ntohs(uh->dest));
 	goto drop;
 
 csum_error:
@@ -1840,10 +1840,10 @@ csum_error:
 	 * RFC1122: OK.  Discards the bad packet silently (as far as
 	 * the network is concerned, anyway) as per 4.1.3.4 (MUST).
 	 */
-	LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n",
-		       proto == IPPROTO_UDPLITE ? "Lite" : "",
-		       &saddr, ntohs(uh->source), &daddr, ntohs(uh->dest),
-		       ulen);
+	net_dbg_ratelimited("UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n",
+			    proto == IPPROTO_UDPLITE ? "Lite" : "",
+			    &saddr, ntohs(uh->source), &daddr, ntohs(uh->dest),
+			    ulen);
 	UDP_INC_STATS_BH(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
 drop:
 	UDP_INC_STATS_BH(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);