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/slab.h> 23 #include <linux/skbuff.h> 24 #include <linux/netlink.h> 25 #include <linux/connector.h> 26 27 #include "w1.h" 28 #include "w1_log.h" 29 #include "w1_netlink.h" 30 31 #if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) || (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE))) 32 void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg) 33 { 34 char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)]; 35 struct cn_msg *m = (struct cn_msg *)buf; 36 struct w1_netlink_msg *w = (struct w1_netlink_msg *)(m+1); 37 38 memset(buf, 0, sizeof(buf)); 39 40 m->id.idx = CN_W1_IDX; 41 m->id.val = CN_W1_VAL; 42 43 m->seq = dev->seq++; 44 m->len = sizeof(struct w1_netlink_msg); 45 46 memcpy(w, msg, sizeof(struct w1_netlink_msg)); 47 48 cn_netlink_send(m, 0, GFP_KERNEL); 49 } 50 51 static void w1_send_slave(struct w1_master *dev, u64 rn) 52 { 53 struct cn_msg *msg = dev->priv; 54 struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1); 55 struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1); 56 int avail; 57 58 avail = dev->priv_size - cmd->len; 59 60 if (avail > 8) { 61 u64 *data = (void *)(cmd + 1) + cmd->len; 62 63 *data = rn; 64 cmd->len += 8; 65 hdr->len += 8; 66 msg->len += 8; 67 return; 68 } 69 70 msg->ack++; 71 cn_netlink_send(msg, 0, GFP_KERNEL); 72 73 msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd); 74 hdr->len = sizeof(struct w1_netlink_cmd); 75 cmd->len = 0; 76 } 77 78 static int w1_process_search_command(struct w1_master *dev, struct cn_msg *msg, 79 unsigned int avail) 80 { 81 struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1); 82 struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1); 83 int search_type = (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH; 84 85 dev->priv = msg; 86 dev->priv_size = avail; 87 88 w1_search_devices(dev, search_type, w1_send_slave); 89 90 msg->ack = 0; 91 cn_netlink_send(msg, 0, GFP_KERNEL); 92 93 dev->priv = NULL; 94 dev->priv_size = 0; 95 96 return 0; 97 } 98 99 static int w1_send_read_reply(struct cn_msg *msg, struct w1_netlink_msg *hdr, 100 struct w1_netlink_cmd *cmd) 101 { 102 void *data; 103 struct w1_netlink_msg *h; 104 struct w1_netlink_cmd *c; 105 struct cn_msg *cm; 106 int err; 107 108 data = kzalloc(sizeof(struct cn_msg) + 109 sizeof(struct w1_netlink_msg) + 110 sizeof(struct w1_netlink_cmd) + 111 cmd->len, GFP_KERNEL); 112 if (!data) 113 return -ENOMEM; 114 115 cm = (struct cn_msg *)(data); 116 h = (struct w1_netlink_msg *)(cm + 1); 117 c = (struct w1_netlink_cmd *)(h + 1); 118 119 memcpy(cm, msg, sizeof(struct cn_msg)); 120 memcpy(h, hdr, sizeof(struct w1_netlink_msg)); 121 memcpy(c, cmd, sizeof(struct w1_netlink_cmd)); 122 123 cm->ack = msg->seq+1; 124 cm->len = sizeof(struct w1_netlink_msg) + 125 sizeof(struct w1_netlink_cmd) + cmd->len; 126 127 h->len = sizeof(struct w1_netlink_cmd) + cmd->len; 128 129 memcpy(c->data, cmd->data, c->len); 130 131 err = cn_netlink_send(cm, 0, GFP_KERNEL); 132 133 kfree(data); 134 135 return err; 136 } 137 138 static int w1_process_command_io(struct w1_master *dev, struct cn_msg *msg, 139 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 140 { 141 int err = 0; 142 143 switch (cmd->cmd) { 144 case W1_CMD_TOUCH: 145 w1_touch_block(dev, cmd->data, cmd->len); 146 w1_send_read_reply(msg, hdr, cmd); 147 break; 148 case W1_CMD_READ: 149 w1_read_block(dev, cmd->data, cmd->len); 150 w1_send_read_reply(msg, hdr, cmd); 151 break; 152 case W1_CMD_WRITE: 153 w1_write_block(dev, cmd->data, cmd->len); 154 break; 155 default: 156 err = -EINVAL; 157 break; 158 } 159 160 return err; 161 } 162 163 static int w1_process_command_master(struct w1_master *dev, struct cn_msg *req_msg, 164 struct w1_netlink_msg *req_hdr, struct w1_netlink_cmd *req_cmd) 165 { 166 int err = -EINVAL; 167 struct cn_msg *msg; 168 struct w1_netlink_msg *hdr; 169 struct w1_netlink_cmd *cmd; 170 171 msg = kzalloc(PAGE_SIZE, GFP_KERNEL); 172 if (!msg) 173 return -ENOMEM; 174 175 msg->id = req_msg->id; 176 msg->seq = req_msg->seq; 177 msg->ack = 0; 178 msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd); 179 180 hdr = (struct w1_netlink_msg *)(msg + 1); 181 cmd = (struct w1_netlink_cmd *)(hdr + 1); 182 183 hdr->type = W1_MASTER_CMD; 184 hdr->id = req_hdr->id; 185 hdr->len = sizeof(struct w1_netlink_cmd); 186 187 cmd->cmd = req_cmd->cmd; 188 cmd->len = 0; 189 190 switch (cmd->cmd) { 191 case W1_CMD_SEARCH: 192 case W1_CMD_ALARM_SEARCH: 193 err = w1_process_search_command(dev, msg, 194 PAGE_SIZE - msg->len - sizeof(struct cn_msg)); 195 break; 196 case W1_CMD_READ: 197 case W1_CMD_WRITE: 198 case W1_CMD_TOUCH: 199 err = w1_process_command_io(dev, req_msg, req_hdr, req_cmd); 200 break; 201 case W1_CMD_RESET: 202 err = w1_reset_bus(dev); 203 break; 204 default: 205 err = -EINVAL; 206 break; 207 } 208 209 kfree(msg); 210 return err; 211 } 212 213 static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg, 214 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 215 { 216 dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n", 217 __func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id, 218 sl->reg_num.crc, cmd->cmd, cmd->len); 219 220 return w1_process_command_io(sl->master, msg, hdr, cmd); 221 } 222 223 static int w1_process_command_root(struct cn_msg *msg, struct w1_netlink_msg *mcmd) 224 { 225 struct w1_master *m; 226 struct cn_msg *cn; 227 struct w1_netlink_msg *w; 228 u32 *id; 229 230 if (mcmd->type != W1_LIST_MASTERS) { 231 printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n", 232 __func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len); 233 return -EPROTO; 234 } 235 236 cn = kmalloc(PAGE_SIZE, GFP_KERNEL); 237 if (!cn) 238 return -ENOMEM; 239 240 cn->id.idx = CN_W1_IDX; 241 cn->id.val = CN_W1_VAL; 242 243 cn->seq = msg->seq; 244 cn->ack = 1; 245 cn->len = sizeof(struct w1_netlink_msg); 246 w = (struct w1_netlink_msg *)(cn + 1); 247 248 w->type = W1_LIST_MASTERS; 249 w->status = 0; 250 w->len = 0; 251 id = (u32 *)(w + 1); 252 253 mutex_lock(&w1_mlock); 254 list_for_each_entry(m, &w1_masters, w1_master_entry) { 255 if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) { 256 cn_netlink_send(cn, 0, GFP_KERNEL); 257 cn->ack++; 258 cn->len = sizeof(struct w1_netlink_msg); 259 w->len = 0; 260 id = (u32 *)(w + 1); 261 } 262 263 *id = m->id; 264 w->len += sizeof(*id); 265 cn->len += sizeof(*id); 266 id++; 267 } 268 cn->ack = 0; 269 cn_netlink_send(cn, 0, GFP_KERNEL); 270 mutex_unlock(&w1_mlock); 271 272 kfree(cn); 273 return 0; 274 } 275 276 static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rmsg, 277 struct w1_netlink_cmd *rcmd, int error) 278 { 279 struct cn_msg *cmsg; 280 struct w1_netlink_msg *msg; 281 struct w1_netlink_cmd *cmd; 282 283 cmsg = kzalloc(sizeof(*msg) + sizeof(*cmd) + sizeof(*cmsg), GFP_KERNEL); 284 if (!cmsg) 285 return -ENOMEM; 286 287 msg = (struct w1_netlink_msg *)(cmsg + 1); 288 cmd = (struct w1_netlink_cmd *)(msg + 1); 289 290 memcpy(cmsg, rcmsg, sizeof(*cmsg)); 291 cmsg->len = sizeof(*msg); 292 293 memcpy(msg, rmsg, sizeof(*msg)); 294 msg->len = 0; 295 msg->status = (short)-error; 296 297 if (rcmd) { 298 memcpy(cmd, rcmd, sizeof(*cmd)); 299 cmd->len = 0; 300 msg->len += sizeof(*cmd); 301 cmsg->len += sizeof(*cmd); 302 } 303 304 error = cn_netlink_send(cmsg, 0, GFP_KERNEL); 305 kfree(cmsg); 306 307 return error; 308 } 309 310 static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp) 311 { 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