Since UDP and UDP-Lite had dedicated socket hash tables for
each, we have had to fetch them from different pointers for
procfs or bpf iterator.

UDP always has its global or per-netns table in
net->ipv4.udp_table and struct udp_seq_afinfo.udp_table
is NULL.

OTOH, UDP-Lite had only one global table in the pointer.

We no longer use the field.

Let's remove it and udp_get_table_seq().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
---
 include/net/udp.h |  1 -
 net/ipv4/udp.c    | 22 ++++------------------
 net/ipv6/udp.c    |  1 -
 3 files changed, 4 insertions(+), 20 deletions(-)

diff --git a/include/net/udp.h b/include/net/udp.h
index 27c3c0c9cf7c..0279a2642c8f 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -551,7 +551,6 @@ static inline int copy_linear_skb(struct sk_buff *skb, int len, int off,
 #ifdef CONFIG_PROC_FS
 struct udp_seq_afinfo {
 	sa_family_t			family;
-	struct udp_table		*udp_table;
 };
 
 struct udp_iter_state {
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index de8d55a9ea5d..6076e20f46f0 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -3186,21 +3186,8 @@ static bool seq_sk_match(struct seq_file *seq, const struct sock *sk)
 
 #ifdef CONFIG_BPF_SYSCALL
 static const struct seq_operations bpf_iter_udp_seq_ops;
-#endif
-static struct udp_table *udp_get_table_seq(struct seq_file *seq,
-					   struct net *net)
-{
-	const struct udp_seq_afinfo *afinfo;
-
-#ifdef CONFIG_BPF_SYSCALL
-	if (seq->op == &bpf_iter_udp_seq_ops)
-		return net->ipv4.udp_table;
 #endif
 
-	afinfo = pde_data(file_inode(seq->file));
-	return afinfo->udp_table ? : net->ipv4.udp_table;
-}
-
 static struct sock *udp_get_first(struct seq_file *seq, int start)
 {
 	struct udp_iter_state *state = seq->private;
@@ -3208,7 +3195,7 @@ static struct sock *udp_get_first(struct seq_file *seq, int start)
 	struct udp_table *udptable;
 	struct sock *sk;
 
-	udptable = udp_get_table_seq(seq, net);
+	udptable = net->ipv4.udp_table;
 
 	for (state->bucket = start; state->bucket <= udptable->mask;
 	     ++state->bucket) {
@@ -3240,7 +3227,7 @@ static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
 	} while (sk && !seq_sk_match(seq, sk));
 
 	if (!sk) {
-		udptable = udp_get_table_seq(seq, net);
+		udptable = net->ipv4.udp_table;
 
 		if (state->bucket <= udptable->mask)
 			spin_unlock_bh(&udptable->hash[state->bucket].lock);
@@ -3288,7 +3275,7 @@ void udp_seq_stop(struct seq_file *seq, void *v)
 	struct udp_iter_state *state = seq->private;
 	struct udp_table *udptable;
 
-	udptable = udp_get_table_seq(seq, seq_file_net(seq));
+	udptable = seq_file_net(seq)->ipv4.udp_table;
 
 	if (state->bucket <= udptable->mask)
 		spin_unlock_bh(&udptable->hash[state->bucket].lock);
@@ -3392,7 +3379,7 @@ static struct sock *bpf_iter_udp_batch(struct seq_file *seq)
 	if (iter->cur_sk == iter->end_sk)
 		state->bucket++;
 
-	udptable = udp_get_table_seq(seq, net);
+	udptable = net->ipv4.udp_table;
 
 again:
 	/* New batch for the next bucket.
@@ -3630,7 +3617,6 @@ const struct seq_operations udp_seq_ops = {
 
 static struct udp_seq_afinfo udp4_seq_afinfo = {
 	.family		= AF_INET,
-	.udp_table	= NULL,
 };
 
 static int __net_init udp4_proc_init_net(struct net *net)
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index abbea5bcbd6f..54b5a92b04d0 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1873,7 +1873,6 @@ static const struct seq_operations udp6_seq_ops = {
 
 static struct udp_seq_afinfo udp6_seq_afinfo = {
 	.family		= AF_INET6,
-	.udp_table	= NULL,
 };
 
 int __net_init udp6_proc_init(struct net *net)
-- 
2.53.0.473.g4a7958ca14-goog