summaryrefslogtreecommitdiff
path: root/net/sctp/ssnmap.c
blob: 737d330e5ffc6a4fdeb4d8b64cccc53e34b619f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
/* 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 <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);
	}
}