File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/net/sctp/ssnmap.c b/net/sctp/ssnmap.c
new file mode 100644
index 0000000..b9c8521
--- /dev/null
+++ b/net/sctp/ssnmap.c
@@ -0,0 +1,125 @@
+/* SCTP kernel implementation
+ * Copyright (c) 2003 International Business Machines, Corp.
+ *
+ * This file is part of the SCTP kernel implementation
+ *
+ * These functions manipulate sctp SSN tracker.
+ *
+ * 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:
+ * Jon Grimm <jgrimm@us.ibm.com>
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+
+static struct sctp_ssnmap *sctp_ssnmap_init(struct sctp_ssnmap *map, __u16 in,
+ __u16 out);
+
+/* Storage size needed for map includes 2 headers and then the
+ * specific needs of in or out streams.
+ */
+static inline size_t sctp_ssnmap_size(__u16 in, __u16 out)
+{
+ return sizeof(struct sctp_ssnmap) + (in + out) * sizeof(__u16);
+}
+
+
+/* Create a new sctp_ssnmap.
+ * Allocate room to store at least 'len' contiguous TSNs.
+ */
+struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
+ gfp_t gfp)
+{
+ struct sctp_ssnmap *retval;
+ int size;
+
+ size = sctp_ssnmap_size(in, out);
+ if (size <= KMALLOC_MAX_SIZE)
+ retval = kmalloc(size, gfp);
+ else
+ retval = (struct sctp_ssnmap *)
+ __get_free_pages(gfp, get_order(size));
+ if (!retval)
+ goto fail;
+
+ if (!sctp_ssnmap_init(retval, in, out))
+ goto fail_map;
+
+ SCTP_DBG_OBJCNT_INC(ssnmap);
+
+ return retval;
+
+fail_map:
+ if (size <= KMALLOC_MAX_SIZE)
+ kfree(retval);
+ else
+ free_pages((unsigned long)retval, get_order(size));
+fail:
+ return NULL;
+}
+
+
+/* Initialize a block of memory as a ssnmap. */
+static struct sctp_ssnmap *sctp_ssnmap_init(struct sctp_ssnmap *map, __u16 in,
+ __u16 out)
+{
+ memset(map, 0x00, sctp_ssnmap_size(in, out));
+
+ /* Start 'in' stream just after the map header. */
+ map->in.ssn = (__u16 *)&map[1];
+ map->in.len = in;
+
+ /* Start 'out' stream just after 'in'. */
+ map->out.ssn = &map->in.ssn[in];
+ map->out.len = out;
+
+ return map;
+}
+
+/* Clear out the ssnmap streams. */
+void sctp_ssnmap_clear(struct sctp_ssnmap *map)
+{
+ size_t size;
+
+ size = (map->in.len + map->out.len) * sizeof(__u16);
+ memset(map->in.ssn, 0x00, size);
+}
+
+/* Dispose of a ssnmap. */
+void sctp_ssnmap_free(struct sctp_ssnmap *map)
+{
+ int size;
+
+ if (unlikely(!map))
+ return;
+
+ size = sctp_ssnmap_size(map->in.len, map->out.len);
+ if (size <= KMALLOC_MAX_SIZE)
+ kfree(map);
+ else
+ free_pages((unsigned long)map, get_order(size));
+
+ SCTP_DBG_OBJCNT_DEC(ssnmap);
+}