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 = -1; 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, msg, hdr, cmd); 199 break; 200 default: 201 cmd->res = EINVAL; 202 cn_netlink_send(msg, 0, GFP_KERNEL); 203 break; 204 } 205 206 kfree(msg); 207 return err; 208 } 209 210 static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg, 211 struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd) 212 { 213 dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n", 214 __func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id, 215 sl->reg_num.crc, cmd->cmd, cmd->len); 216 217 return w1_process_command_io(sl->master, msg, hdr, cmd); 218 } 219 220 static int w1_process_command_root(struct cn_msg *msg, struct w1_netlink_msg *mcmd) 221 { 222 struct w1_master *m; 223 struct cn_msg *cn; 224 struct w1_netlink_msg *w; 225 u32 *id; 226 227 if (mcmd->type != W1_LIST_MASTERS) { 228 printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n", 229 __func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len); 230 return -EPROTO; 231 } 232 233 cn = kmalloc(PAGE_SIZE, GFP_KERNEL); 234 if (!cn) 235 return -ENOMEM; 236 237 cn->id.idx = CN_W1_IDX; 238 cn->id.val = CN_W1_VAL; 239 240 cn->seq = msg->seq; 241 cn->ack = 1; 242 cn->len = sizeof(struct w1_netlink_msg); 243 w = (struct w1_netlink_msg *)(cn + 1); 244 245 w->type = W1_LIST_MASTERS; 246 w->reserved = 0; 247 w->len = 0; 248 id = (u32 *)(w + 1); 249 250 mutex_lock(&w1_mlock); 251 list_for_each_entry(m, &w1_masters, w1_master_entry) { 252 if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) { 253 cn_netlink_send(cn, 0, GFP_KERNEL); 254 cn->ack++; 255 cn->len = sizeof(struct w1_netlink_msg); 256 w->len = 0; 257 id = (u32 *)(w + 1); 258 } 259 260 *id = m->id; 261 w->len += sizeof(*id); 262 cn->len += sizeof(*id); 263 id++; 264 } 265 cn->ack = 0; 266 cn_netlink_send(cn, 0, GFP_KERNEL); 267 mutex_unlock(&w1_mlock); 268 269 kfree(cn); 270 return 0; 271 } 272 273 static void w1_cn_callback(void *data) 274 { 275 struct cn_msg *msg = data; 276 struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1); 277 struct w1_netlink_cmd *cmd; 278 struct w1_slave *sl; 279 struct w1_master *dev; 280 int err = 0; 281 282 while (msg->len && !err) { 283 struct w1_reg_num id; 284 u16 mlen = m->len; 285 u8 *cmd_data = m->data; 286 287 dev = NULL; 288 sl = NULL; 289 290 memcpy(&id, m->id.id, sizeof(id)); 291 #if 0 292 printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n", 293 __func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len); 294 #endif 295 if (m->len + sizeof(struct w1_netlink_msg) > msg->len) { 296 err = -E2BIG; 297 break; 298 } 299 300 if (m->type == W1_MASTER_CMD) { 301 dev = w1_search_master_id(m->id.mst.id); 302 } else if (m->type == W1_SLAVE_CMD) { 303 sl = w1_search_slave(&id); 304 if (sl) 305 dev = sl->master; 306 } else { 307 err = w1_process_command_root(msg, m); 308 goto out_cont; 309 } 310 311 if (!dev) { 312 err = -ENODEV; 313 goto out_cont; 314 } 315 316 err = 0; 317 if (!mlen) 318 goto out_cont; 319 320 mutex_lock(&dev->mutex); 321 322 if (sl && w1_reset_select_slave(sl)) { 323 err = -ENODEV; 324 goto out_up; 325 } 326 327 while (mlen) { 328 cmd = (struct w1_netlink_cmd *)cmd_data; 329 330 if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) { 331 err = -E2BIG; 332 break; 333 } 334 335 if (sl) 336 w1_process_command_slave(sl, msg, m, cmd); 337 else 338 w1_process_command_master(dev, msg, m, cmd); 339 340 cmd_data += cmd->len + sizeof(struct w1_netlink_cmd); 341 mlen -= cmd->len + sizeof(struct w1_netlink_cmd); 342 } 343 out_up: 344 atomic_dec(&dev->refcnt); 345 if (sl) 346 atomic_dec(&sl->refcnt); 347 mutex_unlock(&dev->mutex); 348 out_cont: 349 msg->len -= sizeof(struct w1_netlink_msg) + m->len; 350 m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len); 351 352 /* 353 * Let's allow requests for nonexisting devices. 354 */ 355 if (err == -ENODEV) 356 err = 0; 357 } 358 } 359 360 int w1_init_netlink(void) 361 { 362 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL}; 363 364 return cn_add_callback(&w1_id, "w1", &w1_cn_callback); 365 } 366 367 void w1_fini_netlink(void) 368 { 369 struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL}; 370 371 cn_del_callback(&w1_id); 372 } 373 #else 374 void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg) 375 { 376 } 377 378 int w1_init_netlink(void) 379 { 380 return 0; 381 } 382 383 void w1_fini_netlink(void) 384 { 385 } 386 #endif 387