sctp: export some apis or variables for sctp_diag and reuse some for proc

For some main variables in sctp.ko, we couldn't export it to other modules,
so we have to define some api to access them.

It will include sctp transport and endpoint's traversal.

There are some transport traversal functions for sctp_diag, we can also
use it for sctp_proc. cause they have the similar situation to traversal
transport.

v2->v3:
- rhashtable_walk_init need the parameter gfp, because of recent upstrem
  update

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 18 insertions, 63 deletions

diff --git a/net/sctp/proc.c b/net/sctp/proc.c
index 6d45d53321e6..dd8492f0037d 100644
--- a/net/sctp/proc.c
+++ b/net/sctp/proc.c
@@ -282,81 +282,31 @@ struct sctp_ht_iter {
 	struct rhashtable_iter hti;
 };
 
-static struct sctp_transport *sctp_transport_get_next(struct seq_file *seq)
-{
-	struct sctp_ht_iter *iter = seq->private;
-	struct sctp_transport *t;
-
-	t = rhashtable_walk_next(&iter->hti);
-	for (; t; t = rhashtable_walk_next(&iter->hti)) {
-		if (IS_ERR(t)) {
-			if (PTR_ERR(t) == -EAGAIN)
-				continue;
-			break;
-		}
-
-		if (net_eq(sock_net(t->asoc->base.sk), seq_file_net(seq)) &&
-		    t->asoc->peer.primary_path == t)
-			break;
-	}
-
-	return t;
-}
-
-static struct sctp_transport *sctp_transport_get_idx(struct seq_file *seq,
-						     loff_t pos)
-{
-	void *obj = SEQ_START_TOKEN;
-
-	while (pos && (obj = sctp_transport_get_next(seq)) && !IS_ERR(obj))
-		pos--;
-
-	return obj;
-}
-
-static int sctp_transport_walk_start(struct seq_file *seq)
-{
-	struct sctp_ht_iter *iter = seq->private;
-	int err;
-
-	err = rhashtable_walk_init(&sctp_transport_hashtable, &iter->hti,
-				   GFP_KERNEL);
-	if (err)
-		return err;
-
-	err = rhashtable_walk_start(&iter->hti);
-
-	return err == -EAGAIN ? 0 : err;
-}
-
-static void sctp_transport_walk_stop(struct seq_file *seq)
-{
-	struct sctp_ht_iter *iter = seq->private;
-
-	rhashtable_walk_stop(&iter->hti);
-	rhashtable_walk_exit(&iter->hti);
-}
-
 static void *sctp_assocs_seq_start(struct seq_file *seq, loff_t *pos)
 {
-	int err = sctp_transport_walk_start(seq);
+	struct sctp_ht_iter *iter = seq->private;
+	int err = sctp_transport_walk_start(&iter->hti);
 
 	if (err)
 		return ERR_PTR(err);
 
-	return sctp_transport_get_idx(seq, *pos);
+	return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos);
 }
 
 static void sctp_assocs_seq_stop(struct seq_file *seq, void *v)
 {
-	sctp_transport_walk_stop(seq);
+	struct sctp_ht_iter *iter = seq->private;
+
+	sctp_transport_walk_stop(&iter->hti);
 }
 
 static void *sctp_assocs_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
+	struct sctp_ht_iter *iter = seq->private;
+
 	++*pos;
 
-	return sctp_transport_get_next(seq);
+	return sctp_transport_get_next(seq_file_net(seq), &iter->hti);
 }
 
 /* Display sctp associations (/proc/net/sctp/assocs). */
@@ -458,24 +408,29 @@ void sctp_assocs_proc_exit(struct net *net)
 
 static void *sctp_remaddr_seq_start(struct seq_file *seq, loff_t *pos)
 {
-	int err = sctp_transport_walk_start(seq);
+	struct sctp_ht_iter *iter = seq->private;
+	int err = sctp_transport_walk_start(&iter->hti);
 
 	if (err)
 		return ERR_PTR(err);
 
-	return sctp_transport_get_idx(seq, *pos);
+	return sctp_transport_get_idx(seq_file_net(seq), &iter->hti, *pos);
 }
 
 static void *sctp_remaddr_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
+	struct sctp_ht_iter *iter = seq->private;
+
 	++*pos;
 
-	return sctp_transport_get_next(seq);
+	return sctp_transport_get_next(seq_file_net(seq), &iter->hti);
 }
 
 static void sctp_remaddr_seq_stop(struct seq_file *seq, void *v)
 {
-	sctp_transport_walk_stop(seq);
+	struct sctp_ht_iter *iter = seq->private;
+
+	sctp_transport_walk_stop(&iter->hti);
 }
 
 static int sctp_remaddr_seq_show(struct seq_file *seq, void *v)