1 /* 2 * w1_netlink.c 3 * 4 * Copyright (c) 2003 Evgeniy Polyakov <zbr@ioremap.net> 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 /* update kernel slave list */ 59 w1_slave_found(dev, rn); 60 61 avail = dev->priv_size - cmd->len; 62 63 if (avail > 8) { 64 u64 *data = (void *)(cmd + 1) + cmd->len; 65 66 *data = rn; 67 cmd->len += 8; 68 hdr->len += 8; 69 msg->len += 8; 70 return; 71 } 72 73 msg->ack++; 74 cn_netlink_send(msg, 0, GFP_KERNEL); 75 76 msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd); 77 hdr->len = sizeof(struct w1_netlink_cmd); 78 cmd->len = 0; 79 } 80 81 static int w1_process_search_command(struct w1_master *dev, struct cn_msg *msg, 82 unsigned int avail) 83 { 84 struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1); 85 struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1); 86 int search_type = (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH; 87 88 dev->priv = msg; 89 dev->priv_size = avail; 90 91 w1_search_process_cb(dev, search_type, w1_send_slave); 92 93 msg->ack = 0; 94 cn_netlink_send(msg, 0, GFP_KERNEL); 95 96 dev->priv = NULL; 97 dev->priv_size = 0; 98 99 return 0; 100 } 101 102 static int w1_send_read_reply(struct cn_msg *msg, struct w1_netlink_msg *hdr, 103 struct w1_netlink_cmd *cmd) 104 { 105 void *data; 106 struct w1_netlink_msg *h; 107 struct w1_netlink_cmd *c; 108 struct cn_msg *cm; 109 int err; 110 111 data = kzalloc(sizeof(struct cn_msg) + 112 sizeof(struct w1_netlink_msg) + 113 sizeof(struct w1_netlink_cmd) + 114 cmd->len, GFP_KERNEL); 115 if (!data) 116 return -ENOMEM; 117 118 cm = (struct cn_msg *)(data); 119 h = (struct w1_netlink_msg *)(cm + 1); 120 c = (struct w1_netlink_cmd *)(h + 1); 121 122 memcpy(cm, msg, sizeof(struct cn_msg)); 123 memcpy(h, hdr, sizeof(struct w1_netlink_msg)); 124 memcpy(c, cmd, sizeof(struct w1_netlink_cmd)); 125 126 cm->ack = msg->seq+1; 127 cm->len = sizeof(struct w1_netlink_msg) + 128 sizeof(struct w1_netlink_cmd) + cmd->len; 129 130 h->len = sizeof(struct w1_netlink_cmd) + cmd->len; 131 132 memcpy(c->data, cmd->data, c->len); 133 134 err = cn_netlink_send(cm, 0, GFP_KERNEL); 135 136 kfree(data); 137 138 return err; 139 } 140 141 static int w1_process_command_io(struct w1_master *dev, struct cn_msg *msg, 142 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 143 { 144 int err = 0; 145 146 switch (cmd->cmd) { 147 case W1_CMD_TOUCH: 148 w1_touch_block(dev, cmd->data, cmd->len); 149 w1_send_read_reply(msg, hdr, cmd); 150 break; 151 case W1_CMD_READ: 152 w1_read_block(dev, cmd->data, cmd->len); 153 w1_send_read_reply(msg, hdr, cmd); 154 break; 155 case W1_CMD_WRITE: 156 w1_write_block(dev, cmd->data, cmd->len); 157 break; 158 default: 159 err = -EINVAL; 160 break; 161 } 162 163 return err; 164 } 165 166 static int w1_process_command_master(struct w1_master *dev, struct cn_msg *req_msg, 167 struct w1_netlink_msg *req_hdr, struct w1_netlink_cmd *req_cmd) 168 { 169 int err = -EINVAL; 170 struct cn_msg *msg; 171 struct w1_netlink_msg *hdr; 172 struct w1_netlink_cmd *cmd; 173 174 msg = kzalloc(PAGE_SIZE, GFP_KERNEL); 175 if (!msg) 176 return -ENOMEM; 177 178 msg->id = req_msg->id; 179 msg->seq = req_msg->seq; 180 msg->ack = 0; 181 msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd); 182 183 hdr = (struct w1_netlink_msg *)(msg + 1); 184 cmd = (struct w1_netlink_cmd *)(hdr + 1); 185 186 hdr->type = W1_MASTER_CMD; 187 hdr->id = req_hdr->id; 188 hdr->len = sizeof(struct w1_netlink_cmd); 189 190 cmd->cmd = req_cmd->cmd; 191 cmd->len = 0; 192 193 switch (cmd->cmd) { 194 case W1_CMD_SEARCH: 195 case W1_CMD_ALARM_SEARCH: 196 err = w1_process_search_command(dev, msg, 197 PAGE_SIZE - msg->len - sizeof(struct cn_msg)); 198 break; 199 case W1_CMD_READ: 200 case W1_CMD_WRITE: 201 case W1_CMD_TOUCH: 202 err = w1_process_command_io(dev, req_msg, req_hdr, req_cmd); 203 break; 204 case W1_CMD_RESET: 205 err = w1_reset_bus(dev); 206 break; 207 default: 208 err = -EINVAL; 209 break; 210 } 211 212 kfree(msg); 213 return err; 214 } 215 216 static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg, 217 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 218 { 219 dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n", 220 __func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id, 221 sl->reg_num.crc, cmd->cmd, cmd->len); 222 223 return w1_process_command_io(sl->master, msg, hdr, cmd); 224 } 225 226 static int w1_process_command_root(struct cn_msg *msg, struct w1_netlink_msg *mcmd) 227 { 228 struct w1_master *m; 229 struct cn_msg *cn; 230 struct w1_netlink_msg *w; 231 u32 *id; 232 233 if (mcmd->type != W1_LIST_MASTERS) { 234 printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n", 235 __func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len); 236 return -EPROTO; 237 } 238 239 cn = kmalloc(PAGE_SIZE, GFP_KERNEL); 240 if (!cn) 241 return -ENOMEM; 242 243 cn->id.idx = CN_W1_IDX; 244 cn->id.val = CN_W1_VAL; 245 246 cn->seq = msg->seq; 247 cn->ack = 1; 248 cn->len = sizeof(struct w1_netlink_msg); 249 w = (struct w1_netlink_msg *)(cn + 1); 250 251 w->type = W1_LIST_MASTERS; 252 w->status = 0; 253 w->len = 0; 254 id = (u32 *)(w + 1); 255 256 mutex_lock(&w1_mlock); 257 list_for_each_entry(m, &w1_masters, w1_master_entry) { 258 if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) { 259 cn_netlink_send(cn, 0, GFP_KERNEL); 260 cn->ack++; 261 cn->len = sizeof(struct w1_netlink_msg); 262 w->len = 0; 263 id = (u32 *)(w + 1); 264 } 265 266 *id = m->id; 267 w->len += sizeof(*id); 268 cn->len += sizeof(*id); 269 id++; 270 } 271 cn->ack = 0; 272 cn_netlink_send(cn, 0, GFP_KERNEL); 273 mutex_unlock(&w1_mlock); 274 275 kfree(cn); 276 return 0; 277 } 278 279 static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rmsg, 280 struct w1_netlink_cmd *rcmd, int error) 281 { 282 struct cn_msg *cmsg; 283 struct w1_netlink_msg *msg; 284 struct w1_netlink_cmd *cmd; 285 286 cmsg = kzalloc(sizeof(*msg) + sizeof(*cmd) + sizeof(*cmsg), GFP_KERNEL); 287 if (!cmsg) 288 return -ENOMEM; 289 290 msg = (struct w1_netlink_msg *)(cmsg + 1); 291 cmd = (struct w1_netlink_cmd *)(msg + 1); 292 293 memcpy(cmsg, rcmsg, sizeof(*cmsg)); 294 cmsg->len = sizeof(*msg); 295 296 memcpy(msg, rmsg, sizeof(*msg)); 297 msg->len = 0; 298 msg->status = (short)-error; 299 300 if (rcmd) { 301 memcpy(cmd, rcmd, sizeof(*cmd)); 302 cmd->len = 0; 303 msg->len += sizeof(*cmd); 304 cmsg->len += sizeof(*cmd); 305 } 306 307 error = cn_netlink_send(cmsg, 0, GFP_KERNEL); 308 kfree(cmsg); 309 310 return error; 311 } 312 313 static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp) 314 { 315 struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1); 316 struct w1_netlink_cmd *cmd; 317 struct w1_slave *sl; 318 struct w1_master *dev; 319 int err = 0; 320 321 while (msg->len && !err) { 322 struct w1_reg_num id; 323 u16 mlen = m->len; 324 u8 *cmd_data = m->data; 325 326 dev = NULL; 327 sl = NULL; 328 cmd = NULL; 329 330 memcpy(&id, m->id.id, sizeof(id)); 331 #if 0 332 printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n", 333 __func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len); 334 #endif 335 if (m->len + sizeof(struct w1_netlink_msg) > msg->len) { 336 err = -E2BIG; 337 break; 338 } 339 340 if (m->type == W1_MASTER_CMD) { 341 dev = w1_search_master_id(m->id.mst.id); 342 } else if (m->type == W1_SLAVE_CMD) { 343 sl = w1_search_slave(&id); 344 if (sl) 345 dev = sl->master; 346 } else { 347 err = w1_process_command_root(msg, m); 348 goto out_cont; 349 } 350 351 if (!dev) { 352 err = -ENODEV; 353 goto out_cont; 354 } 355 356 err = 0; 357 if (!mlen) 358 goto out_cont; 359 360 mutex_lock(&dev->mutex); 361 362 if (sl && w1_reset_select_slave(sl)) { 363 err = -ENODEV; 364 goto out_up; 365 } 366 367 while (mlen) { 368 cmd = (struct w1_netlink_cmd *)cmd_data; 369 370 if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) { 371 err = -E2BIG; 372 break; 373 } 374 375 if (sl) 376 err = w1_process_command_slave(sl, msg, m, cmd); 377 else 378 err = w1_process_command_master(dev, msg, m, cmd); 379 380 w1_netlink_send_error(msg, m, cmd, err); 381 err = 0; 382 383 cmd_data += cmd->len + sizeof(struct w1_netlink_cmd); 384 mlen -= cmd->len + sizeof(struct w1_netlink_cmd); 385 } 386 out_up: 387 atomic_dec(&dev->refcnt); 388 if (sl) 389 atomic_dec(&sl->refcnt); 390 mutex_unlock(&dev->mutex); 391 out_cont: 392 if (!cmd || err) 393 w1_netlink_send_error(msg, m, cmd, err); 394 msg->len -= sizeof(struct w1_netlink_msg) + m->len; 395 m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len); 396 397 /* 398 * Let's allow requests for nonexisting devices. 399 */ 400 if (err == -ENODEV) 401 err = 0; 402 } 403 } 404 405 int w1_init_netlink(void) 406 { 407 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL}; 408 409 return cn_add_callback(&w1_id, "w1", &w1_cn_callback); 410 } 411 412 void w1_fini_netlink(void) 413 { 414 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL}; 415 416 cn_del_callback(&w1_id); 417 } 418 #else 419 void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg) 420 { 421 } 422 423 int w1_init_netlink(void) 424 { 425 return 0; 426 } 427 428 void w1_fini_netlink(void) 429 { 430 } 431 #endif 432