1/* SCTP kernel reference Implementation 2 * Copyright (c) 2003 International Business Machines, Corp. 3 * 4 * This file is part of the SCTP kernel reference Implementation 5 * 6 * These functions manipulate sctp SSN tracker. 7 * 8 * The SCTP reference 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 * The SCTP reference 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, write to 22 * the Free Software Foundation, 59 Temple Place - Suite 330, 23 * Boston, MA 02111-1307, USA. 24 * 25 * Please send any bug reports or fixes you make to the 26 * email address(es): 27 * lksctp developers <lksctp-developers@lists.sourceforge.net> 28 * 29 * Or submit a bug report through the following website: 30 * http://www.sf.net/projects/lksctp 31 * 32 * Written or modified by: 33 * Jon Grimm <jgrimm@us.ibm.com> 34 * 35 * Any bugs reported given to us we will try to fix... any fixes shared will 36 * be incorporated into the next SCTP release. 37 */ 38 39#include <linux/types.h> 40#include <net/sctp/sctp.h> 41#include <net/sctp/sm.h> 42 43#define MAX_KMALLOC_SIZE 131072 44 45static struct sctp_ssnmap *sctp_ssnmap_init(struct sctp_ssnmap *map, __u16 in, 46 __u16 out); 47 48/* Storage size needed for map includes 2 headers and then the 49 * specific needs of in or out streams. 50 */ 51static inline size_t sctp_ssnmap_size(__u16 in, __u16 out) 52{ 53 return sizeof(struct sctp_ssnmap) + (in + out) * sizeof(__u16); 54} 55 56 57/* Create a new sctp_ssnmap. 58 * Allocate room to store at least 'len' contiguous TSNs. 59 */ 60struct sctp_ssnmap *sctp_ssnmap_new(__u16 in, __u16 out, 61 gfp_t gfp) 62{ 63 struct sctp_ssnmap *retval; 64 int size; 65 66 size = sctp_ssnmap_size(in, out); 67 if (size <= MAX_KMALLOC_SIZE) 68 retval = kmalloc(size, gfp); 69 else 70 retval = (struct sctp_ssnmap *) 71 __get_free_pages(gfp, get_order(size)); 72 if (!retval) 73 goto fail; 74 75 if (!sctp_ssnmap_init(retval, in, out)) 76 goto fail_map; 77 78 retval->malloced = 1; 79 SCTP_DBG_OBJCNT_INC(ssnmap); 80 81 return retval; 82 83fail_map: 84 if (size <= MAX_KMALLOC_SIZE) 85 kfree(retval); 86 else 87 free_pages((unsigned long)retval, get_order(size)); 88fail: 89 return NULL; 90} 91 92 93/* Initialize a block of memory as a ssnmap. */ 94static struct sctp_ssnmap *sctp_ssnmap_init(struct sctp_ssnmap *map, __u16 in, 95 __u16 out) 96{ 97 memset(map, 0x00, sctp_ssnmap_size(in, out)); 98 99 /* Start 'in' stream just after the map header. */ 100 map->in.ssn = (__u16 *)&map[1]; 101 map->in.len = in; 102 103 /* Start 'out' stream just after 'in'. */ 104 map->out.ssn = &map->in.ssn[in]; 105 map->out.len = out; 106 107 return map; 108} 109 110/* Clear out the ssnmap streams. */ 111void sctp_ssnmap_clear(struct sctp_ssnmap *map) 112{ 113 size_t size; 114 115 size = (map->in.len + map->out.len) * sizeof(__u16); 116 memset(map->in.ssn, 0x00, size); 117} 118 119/* Dispose of a ssnmap. */ 120void sctp_ssnmap_free(struct sctp_ssnmap *map) 121{ 122 if (map && map->malloced) { 123 int size; 124 125 size = sctp_ssnmap_size(map->in.len, map->out.len); 126 if (size <= MAX_KMALLOC_SIZE) 127 kfree(map); 128 else 129 free_pages((unsigned long)map, get_order(size)); 130 SCTP_DBG_OBJCNT_DEC(ssnmap); 131 } 132} 133