blob: b9c8521c1a984be0a34d991413a495282e47f83d [file] [log] [blame]
Kyle Swenson8d8f6542021-03-15 11:02:55 -06001/* SCTP kernel implementation
2 * Copyright (c) 2003 International Business Machines, Corp.
3 *
4 * This file is part of the SCTP kernel implementation
5 *
6 * These functions manipulate sctp SSN tracker.
7 *
8 * This SCTP implementation is free software;
9 * you can redistribute it and/or modify it under the terms of
10 * the GNU General Public License as published by
11 * the Free Software Foundation; either version 2, or (at your option)
12 * any later version.
13 *
14 * This SCTP implementation is distributed in the hope that it
15 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
16 * ************************
17 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
18 * See the GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with GNU CC; see the file COPYING. If not, see
22 * <http://www.gnu.org/licenses/>.
23 *
24 * Please send any bug reports or fixes you make to the
25 * email address(es):
26 * lksctp developers <linux-sctp@vger.kernel.org>
27 *
28 * Written or modified by:
29 * Jon Grimm <jgrimm@us.ibm.com>
30 */
31
32#include <linux/types.h>
33#include <linux/slab.h>
34#include <net/sctp/sctp.h>
35#include <net/sctp/sm.h>
36
37static struct sctp_ssnmap *sctp_ssnmap_init(struct sctp_ssnmap *map, __u16 in,
38 __u16 out);
39
40/* Storage size needed for map includes 2 headers and then the
41 * specific needs of in or out streams.
42 */
43static inline size_t sctp_ssnmap_size(__u16 in, __u16 out)
44{
45 return sizeof(struct sctp_ssnmap) + (in + out) * sizeof(__u16);
46}
47
48
49/* Create a new sctp_ssnmap.
50 * Allocate room to store at least 'len' contiguous TSNs.
51 */
52struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out,
53 gfp_t gfp)
54{
55 struct sctp_ssnmap *retval;
56 int size;
57
58 size = sctp_ssnmap_size(in, out);
59 if (size <= KMALLOC_MAX_SIZE)
60 retval = kmalloc(size, gfp);
61 else
62 retval = (struct sctp_ssnmap *)
63 __get_free_pages(gfp, get_order(size));
64 if (!retval)
65 goto fail;
66
67 if (!sctp_ssnmap_init(retval, in, out))
68 goto fail_map;
69
70 SCTP_DBG_OBJCNT_INC(ssnmap);
71
72 return retval;
73
74fail_map:
75 if (size <= KMALLOC_MAX_SIZE)
76 kfree(retval);
77 else
78 free_pages((unsigned long)retval, get_order(size));
79fail:
80 return NULL;
81}
82
83
84/* Initialize a block of memory as a ssnmap. */
85static struct sctp_ssnmap *sctp_ssnmap_init(struct sctp_ssnmap *map, __u16 in,
86 __u16 out)
87{
88 memset(map, 0x00, sctp_ssnmap_size(in, out));
89
90 /* Start 'in' stream just after the map header. */
91 map->in.ssn = (__u16 *)&map[1];
92 map->in.len = in;
93
94 /* Start 'out' stream just after 'in'. */
95 map->out.ssn = &map->in.ssn[in];
96 map->out.len = out;
97
98 return map;
99}
100
101/* Clear out the ssnmap streams. */
102void sctp_ssnmap_clear(struct sctp_ssnmap *map)
103{
104 size_t size;
105
106 size = (map->in.len + map->out.len) * sizeof(__u16);
107 memset(map->in.ssn, 0x00, size);
108}
109
110/* Dispose of a ssnmap. */
111void sctp_ssnmap_free(struct sctp_ssnmap *map)
112{
113 int size;
114
115 if (unlikely(!map))
116 return;
117
118 size = sctp_ssnmap_size(map->in.len, map->out.len);
119 if (size <= KMALLOC_MAX_SIZE)
120 kfree(map);
121 else
122 free_pages((unsigned long)map, get_order(size));
123
124 SCTP_DBG_OBJCNT_DEC(ssnmap);
125}