Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * llc_core.c - Minimum needed routines for sap handling and module init/exit |
| 3 | * |
| 4 | * Copyright (c) 1997 by Procom Technology, Inc. |
| 5 | * 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| 6 | * |
| 7 | * This program can be redistributed or modified under the terms of the |
| 8 | * GNU General Public License as published by the Free Software Foundation. |
| 9 | * This program is distributed without any warranty or implied warranty |
| 10 | * of merchantability or fitness for a particular purpose. |
| 11 | * |
| 12 | * See the GNU General Public License for more details. |
| 13 | */ |
| 14 | |
| 15 | #include <linux/module.h> |
| 16 | #include <linux/interrupt.h> |
| 17 | #include <linux/if_ether.h> |
| 18 | #include <linux/netdevice.h> |
| 19 | #include <linux/slab.h> |
| 20 | #include <linux/string.h> |
| 21 | #include <linux/init.h> |
Eric W. Biederman | 881d966 | 2007-09-17 11:56:21 -0700 | [diff] [blame] | 22 | #include <net/net_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <net/llc.h> |
| 24 | |
| 25 | LIST_HEAD(llc_sap_list); |
| 26 | DEFINE_RWLOCK(llc_sap_list_lock); |
| 27 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | /** |
| 29 | * llc_sap_alloc - allocates and initializes sap. |
| 30 | * |
| 31 | * Allocates and initializes sap. |
| 32 | */ |
| 33 | static struct llc_sap *llc_sap_alloc(void) |
| 34 | { |
Panagiotis Issaris | 0da974f | 2006-07-21 14:51:30 -0700 | [diff] [blame] | 35 | struct llc_sap *sap = kzalloc(sizeof(*sap), GFP_ATOMIC); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | |
| 37 | if (sap) { |
Joonwoo Park | a5a0481 | 2008-03-28 16:28:36 -0700 | [diff] [blame] | 38 | /* sap->laddr.mac - leave as a null, it's filled by bind */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | sap->state = LLC_SAP_STATE_ACTIVE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | rwlock_init(&sap->sk_list.lock); |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 41 | atomic_set(&sap->refcnt, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | } |
| 43 | return sap; |
| 44 | } |
| 45 | |
| 46 | /** |
| 47 | * llc_add_sap - add sap to station list |
| 48 | * @sap: Address of the sap |
| 49 | * |
| 50 | * Adds a sap to the LLC's station sap list. |
| 51 | */ |
| 52 | static void llc_add_sap(struct llc_sap *sap) |
| 53 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | list_add_tail(&sap->node, &llc_sap_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | } |
| 56 | |
| 57 | /** |
| 58 | * llc_del_sap - del sap from station list |
| 59 | * @sap: Address of the sap |
| 60 | * |
| 61 | * Removes a sap to the LLC's station sap list. |
| 62 | */ |
| 63 | static void llc_del_sap(struct llc_sap *sap) |
| 64 | { |
| 65 | write_lock_bh(&llc_sap_list_lock); |
| 66 | list_del(&sap->node); |
| 67 | write_unlock_bh(&llc_sap_list_lock); |
| 68 | } |
| 69 | |
Arnaldo Carvalho de Melo | 2928c19 | 2005-09-22 05:14:33 -0300 | [diff] [blame] | 70 | static struct llc_sap *__llc_sap_find(unsigned char sap_value) |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 71 | { |
| 72 | struct llc_sap* sap; |
| 73 | |
| 74 | list_for_each_entry(sap, &llc_sap_list, node) |
| 75 | if (sap->laddr.lsap == sap_value) |
| 76 | goto out; |
| 77 | sap = NULL; |
| 78 | out: |
| 79 | return sap; |
| 80 | } |
| 81 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | /** |
| 83 | * llc_sap_find - searchs a SAP in station |
| 84 | * @sap_value: sap to be found |
| 85 | * |
| 86 | * Searchs for a sap in the sap list of the LLC's station upon the sap ID. |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 87 | * If the sap is found it will be refcounted and the user will have to do |
| 88 | * a llc_sap_put after use. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | * Returns the sap or %NULL if not found. |
| 90 | */ |
| 91 | struct llc_sap *llc_sap_find(unsigned char sap_value) |
| 92 | { |
| 93 | struct llc_sap* sap; |
| 94 | |
| 95 | read_lock_bh(&llc_sap_list_lock); |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 96 | sap = __llc_sap_find(sap_value); |
| 97 | if (sap) |
| 98 | llc_sap_hold(sap); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | read_unlock_bh(&llc_sap_list_lock); |
| 100 | return sap; |
| 101 | } |
| 102 | |
| 103 | /** |
| 104 | * llc_sap_open - open interface to the upper layers. |
| 105 | * @lsap: SAP number. |
| 106 | * @func: rcv func for datalink protos |
| 107 | * |
| 108 | * Interface function to upper layer. Each one who wants to get a SAP |
| 109 | * (for example NetBEUI) should call this function. Returns the opened |
| 110 | * SAP for success, NULL for failure. |
| 111 | */ |
| 112 | struct llc_sap *llc_sap_open(unsigned char lsap, |
| 113 | int (*func)(struct sk_buff *skb, |
| 114 | struct net_device *dev, |
David S. Miller | f2ccd8f | 2005-08-09 19:34:12 -0700 | [diff] [blame] | 115 | struct packet_type *pt, |
| 116 | struct net_device *orig_dev)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | { |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 118 | struct llc_sap *sap = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 120 | write_lock_bh(&llc_sap_list_lock); |
| 121 | if (__llc_sap_find(lsap)) /* SAP already exists */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | sap = llc_sap_alloc(); |
| 124 | if (!sap) |
| 125 | goto out; |
| 126 | sap->laddr.lsap = lsap; |
| 127 | sap->rcv_func = func; |
| 128 | llc_add_sap(sap); |
| 129 | out: |
Arnaldo Carvalho de Melo | 6e2144b | 2005-09-22 04:43:05 -0300 | [diff] [blame] | 130 | write_unlock_bh(&llc_sap_list_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | return sap; |
| 132 | } |
| 133 | |
| 134 | /** |
| 135 | * llc_sap_close - close interface for upper layers. |
| 136 | * @sap: SAP to be closed. |
| 137 | * |
| 138 | * Close interface function to upper layer. Each one who wants to |
| 139 | * close an open SAP (for example NetBEUI) should call this function. |
| 140 | * Removes this sap from the list of saps in the station and then |
| 141 | * frees the memory for this sap. |
| 142 | */ |
| 143 | void llc_sap_close(struct llc_sap *sap) |
| 144 | { |
| 145 | WARN_ON(!hlist_empty(&sap->sk_list.list)); |
| 146 | llc_del_sap(sap); |
| 147 | kfree(sap); |
| 148 | } |
| 149 | |
| 150 | static struct packet_type llc_packet_type = { |
Harvey Harrison | 09640e6 | 2009-02-01 00:45:17 -0800 | [diff] [blame^] | 151 | .type = cpu_to_be16(ETH_P_802_2), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | .func = llc_rcv, |
| 153 | }; |
| 154 | |
| 155 | static struct packet_type llc_tr_packet_type = { |
Harvey Harrison | 09640e6 | 2009-02-01 00:45:17 -0800 | [diff] [blame^] | 156 | .type = cpu_to_be16(ETH_P_TR_802_2), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | .func = llc_rcv, |
| 158 | }; |
| 159 | |
| 160 | static int __init llc_init(void) |
| 161 | { |
Pavel Emelianov | 7562f87 | 2007-05-03 15:13:45 -0700 | [diff] [blame] | 162 | struct net_device *dev; |
| 163 | |
Eric W. Biederman | 881d966 | 2007-09-17 11:56:21 -0700 | [diff] [blame] | 164 | dev = first_net_device(&init_net); |
Pavel Emelianov | 7562f87 | 2007-05-03 15:13:45 -0700 | [diff] [blame] | 165 | if (dev != NULL) |
| 166 | dev = next_net_device(dev); |
| 167 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | dev_add_pack(&llc_packet_type); |
| 169 | dev_add_pack(&llc_tr_packet_type); |
| 170 | return 0; |
| 171 | } |
| 172 | |
| 173 | static void __exit llc_exit(void) |
| 174 | { |
| 175 | dev_remove_pack(&llc_packet_type); |
| 176 | dev_remove_pack(&llc_tr_packet_type); |
| 177 | } |
| 178 | |
| 179 | module_init(llc_init); |
| 180 | module_exit(llc_exit); |
| 181 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | EXPORT_SYMBOL(llc_sap_list); |
| 183 | EXPORT_SYMBOL(llc_sap_list_lock); |
| 184 | EXPORT_SYMBOL(llc_sap_find); |
| 185 | EXPORT_SYMBOL(llc_sap_open); |
| 186 | EXPORT_SYMBOL(llc_sap_close); |
| 187 | |
| 188 | MODULE_LICENSE("GPL"); |
| 189 | MODULE_AUTHOR("Procom 1997, Jay Schullist 2001, Arnaldo C. Melo 2001-2003"); |
| 190 | MODULE_DESCRIPTION("LLC IEEE 802.2 core support"); |