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))) 31 void 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 50 static void w1_send_slave(struct w1_master *dev, u64 rn) 51 { 52 struct cn_msg *msg = dev->priv; 53 struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1); 54 struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1); 55 int avail; 56 57 avail = dev->priv_size - cmd->len; 58 59 if (avail > 8) { 60 u64 *data = (void *)(cmd + 1) + cmd->len; 61 62 *data = rn; 63 cmd->len += 8; 64 hdr->len += 8; 65 msg->len += 8; 66 return; 67 } 68 69 msg->ack++; 70 cn_netlink_send(msg, 0, GFP_KERNEL); 71 72 msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd); 73 hdr->len = sizeof(struct w1_netlink_cmd); 74 cmd->len = 0; 75 } 76 77 static int w1_process_search_command(struct w1_master *dev, struct cn_msg *msg, 78 unsigned int avail) 79 { 80 struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1); 81 struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1); 82 int search_type = (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH; 83 84 dev->priv = msg; 85 dev->priv_size = avail; 86 87 w1_search_devices(dev, search_type, w1_send_slave); 88 89 msg->ack = 0; 90 cn_netlink_send(msg, 0, GFP_KERNEL); 91 92 dev->priv = NULL; 93 dev->priv_size = 0; 94 95 return 0; 96 } 97 98 static int w1_send_read_reply(struct cn_msg *msg, struct w1_netlink_msg *hdr, 99 struct w1_netlink_cmd *cmd) 100 { 101 void *data; 102 struct w1_netlink_msg *h; 103 struct w1_netlink_cmd *c; 104 struct cn_msg *cm; 105 int err; 106 107 data = kzalloc(sizeof(struct cn_msg) + 108 sizeof(struct w1_netlink_msg) + 109 sizeof(struct w1_netlink_cmd) + 110 cmd->len, GFP_KERNEL); 111 if (!data) 112 return -ENOMEM; 113 114 cm = (struct cn_msg *)(data); 115 h = (struct w1_netlink_msg *)(cm + 1); 116 c = (struct w1_netlink_cmd *)(h + 1); 117 118 memcpy(cm, msg, sizeof(struct cn_msg)); 119 memcpy(h, hdr, sizeof(struct w1_netlink_msg)); 120 memcpy(c, cmd, sizeof(struct w1_netlink_cmd)); 121 122 cm->ack = msg->seq+1; 123 cm->len = sizeof(struct w1_netlink_msg) + 124 sizeof(struct w1_netlink_cmd) + cmd->len; 125 126 h->len = sizeof(struct w1_netlink_cmd) + cmd->len; 127 128 memcpy(c->data, cmd->data, c->len); 129 130 err = cn_netlink_send(cm, 0, GFP_KERNEL); 131 132 kfree(data); 133 134 return err; 135 } 136 137 static int w1_process_command_io(struct w1_master *dev, struct cn_msg *msg, 138 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 139 { 140 int err = 0; 141 142 switch (cmd->cmd) { 143 case W1_CMD_TOUCH: 144 w1_touch_block(dev, cmd->data, cmd->len); 145 w1_send_read_reply(msg, hdr, cmd); 146 break; 147 case W1_CMD_READ: 148 w1_read_block(dev, cmd->data, cmd->len); 149 w1_send_read_reply(msg, hdr, cmd); 150 break; 151 case W1_CMD_WRITE: 152 w1_write_block(dev, cmd->data, cmd->len); 153 break; 154 default: 155 err = -EINVAL; 156 break; 157 } 158 159 return err; 160 } 161 162 static int w1_process_command_master(struct w1_master *dev, struct cn_msg *req_msg, 163 struct w1_netlink_msg *req_hdr, struct w1_netlink_cmd *req_cmd) 164 { 165 int err = -EINVAL; 166 struct cn_msg *msg; 167 struct w1_netlink_msg *hdr; 168 struct w1_netlink_cmd *cmd; 169 170 msg = kzalloc(PAGE_SIZE, GFP_KERNEL); 171 if (!msg) 172 return -ENOMEM; 173 174 msg->id = req_msg->id; 175 msg->seq = req_msg->seq; 176 msg->ack = 0; 177 msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd); 178 179 hdr = (struct w1_netlink_msg *)(msg + 1); 180 cmd = (struct w1_netlink_cmd *)(hdr + 1); 181 182 hdr->type = W1_MASTER_CMD; 183 hdr->id = req_hdr->id; 184 hdr->len = sizeof(struct w1_netlink_cmd); 185 186 cmd->cmd = req_cmd->cmd; 187 cmd->len = 0; 188 189 switch (cmd->cmd) { 190 case W1_CMD_SEARCH: 191 case W1_CMD_ALARM_SEARCH: 192 err = w1_process_search_command(dev, msg, 193 PAGE_SIZE - msg->len - sizeof(struct cn_msg)); 194 break; 195 case W1_CMD_READ: 196 case W1_CMD_WRITE: 197 case W1_CMD_TOUCH: 198 err = w1_process_command_io(dev, req_msg, req_hdr, req_cmd); 199 break; 200 case W1_CMD_RESET: 201 err = w1_reset_bus(dev); 202 break; 203 default: 204 err = -EINVAL; 205 break; 206 } 207 208 kfree(msg); 209 return err; 210 } 211 212 static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg, 213 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 214 { 215 dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n", 216 __func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id, 217 sl->reg_num.crc, cmd->cmd, cmd->len); 218 219 return w1_process_command_io(sl->master, msg, hdr, cmd); 220 } 221 222 static int w1_process_command_root(struct cn_msg *msg, struct w1_netlink_msg *mcmd) 223 { 224 struct w1_master *m; 225 struct cn_msg *cn; 226 struct w1_netlink_msg *w; 227 u32 *id; 228 229 if (mcmd->type != W1_LIST_MASTERS) { 230 printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n", 231 __func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len); 232 return -EPROTO; 233 } 234 235 cn = kmalloc(PAGE_SIZE, GFP_KERNEL); 236 if (!cn) 237 return -ENOMEM; 238 239 cn->id.idx = CN_W1_IDX; 240 cn->id.val = CN_W1_VAL; 241 242 cn->seq = msg->seq; 243 cn->ack = 1; 244 cn->len = sizeof(struct w1_netlink_msg); 245 w = (struct w1_netlink_msg *)(cn + 1); 246 247 w->type = W1_LIST_MASTERS; 248 w->status = 0; 249 w->len = 0; 250 id = (u32 *)(w + 1); 251 252 mutex_lock(&w1_mlock); 253 list_for_each_entry(m, &w1_masters, w1_master_entry) { 254 if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) { 255 cn_netlink_send(cn, 0, GFP_KERNEL); 256 cn->ack++; 257 cn->len = sizeof(struct w1_netlink_msg); 258 w->len = 0; 259 id = (u32 *)(w + 1); 260 } 261 262 *id = m->id; 263 w->len += sizeof(*id); 264 cn->len += sizeof(*id); 265 id++; 266 } 267 cn->ack = 0; 268 cn_netlink_send(cn, 0, GFP_KERNEL); 269 mutex_unlock(&w1_mlock); 270 271 kfree(cn); 272 return 0; 273 } 274 275 static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rmsg, 276 struct w1_netlink_cmd *rcmd, int error) 277 { 278 struct cn_msg *cmsg; 279 struct w1_netlink_msg *msg; 280 struct w1_netlink_cmd *cmd; 281 282 cmsg = kzalloc(sizeof(*msg) + sizeof(*cmd) + sizeof(*cmsg), GFP_KERNEL); 283 if (!cmsg) 284 return -ENOMEM; 285 286 msg = (struct w1_netlink_msg *)(cmsg + 1); 287 cmd = (struct w1_netlink_cmd *)(msg + 1); 288 289 memcpy(cmsg, rcmsg, sizeof(*cmsg)); 290 cmsg->len = sizeof(*msg); 291 292 memcpy(msg, rmsg, sizeof(*msg)); 293 msg->len = 0; 294 msg->status = (short)-error; 295 296 if (rcmd) { 297 memcpy(cmd, rcmd, sizeof(*cmd)); 298 cmd->len = 0; 299 msg->len += sizeof(*cmd); 300 cmsg->len += sizeof(*cmd); 301 } 302 303 error = cn_netlink_send(cmsg, 0, GFP_KERNEL); 304 kfree(cmsg); 305 306 return error; 307 } 308 309 static void w1_cn_callback(void *data) 310 { 311 struct cn_msg *msg = data; 312 struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1); 313 struct w1_netlink_cmd *cmd; 314 struct w1_slave *sl; 315 struct w1_master *dev; 316 int err = 0; 317 318 while (msg->len && !err) { 319 struct w1_reg_num id; 320 u16 mlen = m->len; 321 u8 *cmd_data = m->data; 322 323 dev = NULL; 324 sl = NULL; 325 cmd = NULL; 326 327 memcpy(&id, m->id.id, sizeof(id)); 328 #if 0 329 printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n", 330 __func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len); 331 #endif 332 if (m->len + sizeof(struct w1_netlink_msg) > msg->len) { 333 err = -E2BIG; 334 break; 335 } 336 337 if (m->type == W1_MASTER_CMD) { 338 dev = w1_search_master_id(m->id.mst.id); 339 } else if (m->type == W1_SLAVE_CMD) { 340 sl = w1_search_slave(&id); 341 if (sl) 342 dev = sl->master; 343 } else { 344 err = w1_process_command_root(msg, m); 345 goto out_cont; 346 } 347 348 if (!dev) { 349 err = -ENODEV; 350 goto out_cont; 351 } 352 353 err = 0; 354 if (!mlen) 355 goto out_cont; 356 357 mutex_lock(&dev->mutex); 358 359 if (sl && w1_reset_select_slave(sl)) { 360 err = -ENODEV; 361 goto out_up; 362 } 363 364 while (mlen) { 365 cmd = (struct w1_netlink_cmd *)cmd_data; 366 367 if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) { 368 err = -E2BIG; 369 break; 370 } 371 372 if (sl) 373 err = w1_process_command_slave(sl, msg, m, cmd); 374 else 375 err = w1_process_command_master(dev, msg, m, cmd); 376 377 w1_netlink_send_error(msg, m, cmd, err); 378 err = 0; 379 380 cmd_data += cmd->len + sizeof(struct w1_netlink_cmd); 381 mlen -= cmd->len + sizeof(struct w1_netlink_cmd); 382 } 383 out_up: 384 atomic_dec(&dev->refcnt); 385 if (sl) 386 atomic_dec(&sl->refcnt); 387 mutex_unlock(&dev->mutex); 388 out_cont: 389 if (!cmd || err) 390 w1_netlink_send_error(msg, m, cmd, err); 391 msg->len -= sizeof(struct w1_netlink_msg) + m->len; 392 m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len); 393 394 /* 395 * Let's allow requests for nonexisting devices. 396 */ 397 if (err == -ENODEV) 398 err = 0; 399 } 400 } 401 402 int w1_init_netlink(void) 403 { 404 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL}; 405 406 return cn_add_callback(&w1_id, "w1", &w1_cn_callback); 407 } 408 409 void w1_fini_netlink(void) 410 { 411 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL}; 412 413 cn_del_callback(&w1_id); 414 } 415 #else 416 void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg) 417 { 418 } 419 420 int w1_init_netlink(void) 421 { 422 return 0; 423 } 424 425 void w1_fini_netlink(void) 426 { 427 } 428 #endif 429