sctp: prepare asoc stream for stream reconf

sctp stream reconf, described in RFC 6525, needs a structure to
save per stream information in assoc, like stream state.

In the future, sctp stream scheduler also needs it to save some
stream scheduler params and queues.

This patchset is to prepare the stream array in assoc for stream
reconf. It defines sctp_stream that includes stream arrays inside
to replace ssnmap.

Note that we use different structures for IN and OUT streams, as
the members in per OUT stream will get more and more different
from per IN stream.

v1->v2:
  - put these patches into a smaller group.
v2->v3:
  - define sctp_stream to contain stream arrays, and create stream.c
    to put stream-related functions.
  - merge 3 patches into 1, as new sctp_stream has the same name
    with before.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 85 insertions, 0 deletions

diff --git a/net/sctp/stream.c b/net/sctp/stream.c
new file mode 100644
index 000000000000..f86de43cbbe5
--- /dev/null
+++ b/net/sctp/stream.c
@@ -0,0 +1,85 @@
+/* SCTP kernel implementation
+ * (C) Copyright IBM Corp. 2001, 2004
+ * Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001 Intel Corp.
+ *
+ * This file is part of the SCTP kernel implementation
+ *
+ * These functions manipulate sctp tsn mapping array.
+ *
+ * This SCTP implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This SCTP implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ *                 ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ *    lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ *    Xin Long <lucien.xin@gmail.com>
+ */
+
+#include <net/sctp/sctp.h>
+
+struct sctp_stream *sctp_stream_new(__u16 incnt, __u16 outcnt, gfp_t gfp)
+{
+	struct sctp_stream *stream;
+	int i;
+
+	stream = kzalloc(sizeof(*stream), gfp);
+	if (!stream)
+		return NULL;
+
+	stream->outcnt = outcnt;
+	stream->out = kcalloc(stream->outcnt, sizeof(*stream->out), gfp);
+	if (!stream->out) {
+		kfree(stream);
+		return NULL;
+	}
+	for (i = 0; i < stream->outcnt; i++)
+		stream->out[i].state = SCTP_STREAM_OPEN;
+
+	stream->incnt = incnt;
+	stream->in = kcalloc(stream->incnt, sizeof(*stream->in), gfp);
+	if (!stream->in) {
+		kfree(stream->out);
+		kfree(stream);
+		return NULL;
+	}
+
+	return stream;
+}
+
+void sctp_stream_free(struct sctp_stream *stream)
+{
+	if (unlikely(!stream))
+		return;
+
+	kfree(stream->out);
+	kfree(stream->in);
+	kfree(stream);
+}
+
+void sctp_stream_clear(struct sctp_stream *stream)
+{
+	int i;
+
+	for (i = 0; i < stream->outcnt; i++)
+		stream->out[i].ssn = 0;
+
+	for (i = 0; i < stream->incnt; i++)
+		stream->in[i].ssn = 0;
+}