w1_netlink.c revision abd52a13206e02537ca1dc08fc5438c7d27bdbf1
1/* 2 * w1_netlink.c 3 * 4 * Copyright (c) 2003 Evgeniy Polyakov <johnpol@2ka.mipt.ru> 5 * 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22#include <linux/skbuff.h> 23#include <linux/netlink.h> 24#include <linux/connector.h> 25 26#include "w1.h" 27#include "w1_log.h" 28#include "w1_netlink.h" 29 30#if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) || (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE))) 31void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg) 32{ 33 char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)]; 34 struct cn_msg *m = (struct cn_msg *)buf; 35 struct w1_netlink_msg *w = (struct w1_netlink_msg *)(m+1); 36 37 memset(buf, 0, sizeof(buf)); 38 39 m->id.idx = CN_W1_IDX; 40 m->id.val = CN_W1_VAL; 41 42 m->seq = dev->seq++; 43 m->len = sizeof(struct w1_netlink_msg); 44 45 memcpy(w, msg, sizeof(struct w1_netlink_msg)); 46 47 cn_netlink_send(m, 0, GFP_KERNEL); 48} 49 50static int w1_process_command_master(struct w1_master *dev, struct cn_msg *msg, 51 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 52{ 53 dev_dbg(&dev->dev, "%s: %s: cmd=%02x, len=%u.\n", 54 __func__, dev->name, cmd->cmd, cmd->len); 55 56 if (cmd->cmd != W1_CMD_SEARCH && cmd->cmd != W1_CMD_ALARM_SEARCH) 57 return -EINVAL; 58 59 w1_search_process(dev, (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH); 60 return 0; 61} 62 63static int w1_send_read_reply(struct w1_slave *sl, struct cn_msg *msg, 64 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 65{ 66 void *data; 67 struct w1_netlink_msg *h; 68 struct w1_netlink_cmd *c; 69 struct cn_msg *cm; 70 int err; 71 72 data = kzalloc(sizeof(struct cn_msg) + 73 sizeof(struct w1_netlink_msg) + 74 sizeof(struct w1_netlink_cmd) + 75 cmd->len, GFP_KERNEL); 76 if (!data) 77 return -ENOMEM; 78 79 cm = (struct cn_msg *)(data); 80 h = (struct w1_netlink_msg *)(cm + 1); 81 c = (struct w1_netlink_cmd *)(h + 1); 82 83 memcpy(cm, msg, sizeof(struct cn_msg)); 84 memcpy(h, hdr, sizeof(struct w1_netlink_msg)); 85 memcpy(c, cmd, sizeof(struct w1_netlink_cmd)); 86 87 cm->ack = msg->seq+1; 88 cm->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd) + cmd->len; 89 90 h->len = sizeof(struct w1_netlink_cmd) + cmd->len; 91 92 memcpy(c->data, cmd->data, c->len); 93 94 err = cn_netlink_send(cm, 0, GFP_KERNEL); 95 96 kfree(data); 97 98 return err; 99} 100 101static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg, 102 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 103{ 104 int err = 0; 105 106 dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n", 107 __func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id, sl->reg_num.crc, 108 cmd->cmd, cmd->len); 109 110 switch (cmd->cmd) { 111 case W1_CMD_READ: 112 w1_read_block(sl->master, cmd->data, cmd->len); 113 w1_send_read_reply(sl, msg, hdr, cmd); 114 break; 115 case W1_CMD_WRITE: 116 w1_write_block(sl->master, cmd->data, cmd->len); 117 break; 118 case W1_CMD_SEARCH: 119 case W1_CMD_ALARM_SEARCH: 120 w1_search_process(sl->master, 121 (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH); 122 break; 123 default: 124 err = -1; 125 break; 126 } 127 128 return err; 129} 130 131static void w1_cn_callback(void *data) 132{ 133 struct cn_msg *msg = data; 134 struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1); 135 struct w1_netlink_cmd *cmd; 136 struct w1_slave *sl; 137 struct w1_master *dev; 138 int err = 0; 139 140 while (msg->len && !err) { 141 struct w1_reg_num id; 142 u16 mlen = m->len; 143 u8 *cmd_data = m->data; 144 145 dev = NULL; 146 sl = NULL; 147 148 memcpy(&id, m->id.id, sizeof(id)); 149#if 0 150 printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n", 151 __func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len); 152#endif 153 if (m->len + sizeof(struct w1_netlink_msg) > msg->len) { 154 err = -E2BIG; 155 break; 156 } 157 158 if (!mlen) 159 goto out_cont; 160 161 if (m->type == W1_MASTER_CMD) { 162 dev = w1_search_master_id(m->id.mst.id); 163 } else if (m->type == W1_SLAVE_CMD) { 164 sl = w1_search_slave(&id); 165 if (sl) 166 dev = sl->master; 167 } 168 169 if (!dev) { 170 err = -ENODEV; 171 goto out_cont; 172 } 173 174 mutex_lock(&dev->mutex); 175 176 if (sl && w1_reset_select_slave(sl)) { 177 err = -ENODEV; 178 goto out_up; 179 } 180 181 while (mlen) { 182 cmd = (struct w1_netlink_cmd *)cmd_data; 183 184 if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) { 185 err = -E2BIG; 186 break; 187 } 188 189 if (sl) 190 w1_process_command_slave(sl, msg, m, cmd); 191 else 192 w1_process_command_master(dev, msg, m, cmd); 193 194 cmd_data += cmd->len + sizeof(struct w1_netlink_cmd); 195 mlen -= cmd->len + sizeof(struct w1_netlink_cmd); 196 } 197out_up: 198 atomic_dec(&dev->refcnt); 199 if (sl) 200 atomic_dec(&sl->refcnt); 201 mutex_unlock(&dev->mutex); 202out_cont: 203 msg->len -= sizeof(struct w1_netlink_msg) + m->len; 204 m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len); 205 206 /* 207 * Let's allow requests for nonexisting devices. 208 */ 209 if (err == -ENODEV) 210 err = 0; 211 } 212#if 0 213 if (err) { 214 printk("%s: malformed message. Dropping.\n", __func__); 215 } 216#endif 217} 218 219int w1_init_netlink(void) 220{ 221 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL}; 222 223 return cn_add_callback(&w1_id, "w1", &w1_cn_callback); 224} 225 226void w1_fini_netlink(void) 227{ 228 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL}; 229 230 cn_del_callback(&w1_id); 231} 232#else 233void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg) 234{ 235} 236 237int w1_init_netlink(void) 238{ 239 return 0; 240} 241 242void w1_fini_netlink(void) 243{ 244} 245#endif 246