/* 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, write to
* the Free Software Foundation, 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Please send any bug reports or fixes you make to the
* email address(es):
* lksctp developers <lksctp-developers@lists.sourceforge.net>
*
* Or submit a bug report through the following website:
* http://www.sf.net/projects/lksctp
*
* Written or modified by:
* Jon Grimm <jgrimm@us.ibm.com>
*
* Any bugs reported given to us we will try to fix... any fixes shared will
* be incorporated into the next SCTP release.
*/
#include <linux/types.h>
#include <linux/slab.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>
#define MAX_KMALLOC_SIZE 131072
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 <= MAX_KMALLOC_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;
retval->malloced = 1;
SCTP_DBG_OBJCNT_INC(ssnmap);
return retval;
fail_map:
if (size <= MAX_KMALLOC_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)
{
if (map && map->malloced) {
int size;
size = sctp_ssnmap_size(map->in.len, map->out.len);
if (size <= MAX_KMALLOC_SIZE)
kfree(map);
else
free_pages((unsigned long)map, get_order(size));
SCTP_DBG_OBJCNT_DEC(ssnmap);
}
}
