1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * ipmi_devintf.c 4 * 5 * Linux device interface for the IPMI message handler. 6 * 7 * Author: MontaVista Software, Inc. 8 * Corey Minyard <minyard@mvista.com> 9 * source@mvista.com 10 * 11 * Copyright 2002 MontaVista Software Inc. 12 */ 13 14 #include <linux/module.h> 15 #include <linux/moduleparam.h> 16 #include <linux/errno.h> 17 #include <linux/poll.h> 18 #include <linux/sched.h> 19 #include <linux/spinlock.h> 20 #include <linux/slab.h> 21 #include <linux/ipmi.h> 22 #include <linux/mutex.h> 23 #include <linux/init.h> 24 #include <linux/device.h> 25 #include <linux/compat.h> 26 27 struct ipmi_file_private 28 { 29 struct ipmi_user *user; 30 spinlock_t recv_msg_lock; 31 struct list_head recv_msgs; 32 struct fasync_struct *fasync_queue; 33 wait_queue_head_t wait; 34 struct mutex recv_mutex; 35 int default_retries; 36 unsigned int default_retry_time_ms; 37 }; 38 39 static void file_receive_handler(struct ipmi_recv_msg *msg, 40 void *handler_data) 41 { 42 struct ipmi_file_private *priv = handler_data; 43 int was_empty; 44 unsigned long flags; 45 46 spin_lock_irqsave(&priv->recv_msg_lock, flags); 47 was_empty = list_empty(&priv->recv_msgs); 48 list_add_tail(&msg->link, &priv->recv_msgs); 49 spin_unlock_irqrestore(&priv->recv_msg_lock, flags); 50 51 if (was_empty) { 52 wake_up_interruptible(&priv->wait); 53 kill_fasync(&priv->fasync_queue, SIGIO, POLL_IN); 54 } 55 } 56 57 static __poll_t ipmi_poll(struct file *file, poll_table *wait) 58 { 59 struct ipmi_file_private *priv = file->private_data; 60 __poll_t mask = 0; 61 unsigned long flags; 62 63 poll_wait(file, &priv->wait, wait); 64 65 spin_lock_irqsave(&priv->recv_msg_lock, flags); 66 67 if (!list_empty(&priv->recv_msgs)) 68 mask |= (EPOLLIN | EPOLLRDNORM); 69 70 spin_unlock_irqrestore(&priv->recv_msg_lock, flags); 71 72 return mask; 73 } 74 75 static int ipmi_fasync(int fd, struct file *file, int on) 76 { 77 struct ipmi_file_private *priv = file->private_data; 78 79 return fasync_helper(fd, file, on, &priv->fasync_queue); 80 } 81 82 static const struct ipmi_user_hndl ipmi_hndlrs = 83 { 84 .ipmi_recv_hndl = file_receive_handler, 85 }; 86 87 static int ipmi_open(struct inode *inode, struct file *file) 88 { 89 int if_num = iminor(inode); 90 int rv; 91 struct ipmi_file_private *priv; 92 93 priv = kmalloc(sizeof(*priv), GFP_KERNEL); 94 if (!priv) 95 return -ENOMEM; 96 97 rv = ipmi_create_user(if_num, 98 &ipmi_hndlrs, 99 priv, 100 &priv->user); 101 if (rv) { 102 kfree(priv); 103 goto out; 104 } 105 106 file->private_data = priv; 107 108 spin_lock_init(&priv->recv_msg_lock); 109 INIT_LIST_HEAD(&priv->recv_msgs); 110 init_waitqueue_head(&priv->wait); 111 priv->fasync_queue = NULL; 112 mutex_init(&priv->recv_mutex); 113 114 /* Use the low-level defaults. */ 115 priv->default_retries = -1; 116 priv->default_retry_time_ms = 0; 117 118 out: 119 return rv; 120 } 121 122 static int ipmi_release(struct inode *inode, struct file *file) 123 { 124 struct ipmi_file_private *priv = file->private_data; 125 int rv; 126 struct ipmi_recv_msg *msg, *next; 127 128 rv = ipmi_destroy_user(priv->user); 129 if (rv) 130 return rv; 131 132 list_for_each_entry_safe(msg, next, &priv->recv_msgs, link) 133 ipmi_free_recv_msg(msg); 134 135 kfree(priv); 136 137 return 0; 138 } 139 140 static int handle_send_req(struct ipmi_user *user, 141 struct ipmi_req *req, 142 int retries, 143 unsigned int retry_time_ms) 144 { 145 int rv; 146 struct ipmi_addr addr; 147 struct kernel_ipmi_msg msg; 148 149 if (req->addr_len > sizeof(struct ipmi_addr)) 150 return -EINVAL; 151 152 if (copy_from_user(&addr, req->addr, req->addr_len)) 153 return -EFAULT; 154 155 msg.netfn = req->msg.netfn; 156 msg.cmd = req->msg.cmd; 157 msg.data_len = req->msg.data_len; 158 msg.data = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL); 159 if (!msg.data) 160 return -ENOMEM; 161 162 /* From here out we cannot return, we must jump to "out" for 163 error exits to free msgdata. */ 164 165 rv = ipmi_validate_addr(&addr, req->addr_len); 166 if (rv) 167 goto out; 168 169 if (req->msg.data != NULL) { 170 if (req->msg.data_len > IPMI_MAX_MSG_LENGTH) { 171 rv = -EMSGSIZE; 172 goto out; 173 } 174 175 if (copy_from_user(msg.data, 176 req->msg.data, 177 req->msg.data_len)) { 178 rv = -EFAULT; 179 goto out; 180 } 181 } else { 182 msg.data_len = 0; 183 } 184 185 rv = ipmi_request_settime(user, 186 &addr, 187 req->msgid, 188 &msg, 189 NULL, 190 0, 191 retries, 192 retry_time_ms); 193 out: 194 kfree(msg.data); 195 return rv; 196 } 197 198 static int handle_recv(struct ipmi_file_private *priv, 199 bool trunc, struct ipmi_recv *rsp, 200 int (*copyout)(struct ipmi_recv *, void __user *), 201 void __user *to) 202 { 203 int addr_len; 204 struct list_head *entry; 205 struct ipmi_recv_msg *msg; 206 unsigned long flags; 207 int rv = 0, rv2 = 0; 208 209 /* We claim a mutex because we don't want two 210 users getting something from the queue at a time. 211 Since we have to release the spinlock before we can 212 copy the data to the user, it's possible another 213 user will grab something from the queue, too. Then 214 the messages might get out of order if something 215 fails and the message gets put back onto the 216 queue. This mutex prevents that problem. */ 217 mutex_lock(&priv->recv_mutex); 218 219 /* Grab the message off the list. */ 220 spin_lock_irqsave(&priv->recv_msg_lock, flags); 221 if (list_empty(&(priv->recv_msgs))) { 222 spin_unlock_irqrestore(&priv->recv_msg_lock, flags); 223 rv = -EAGAIN; 224 goto recv_err; 225 } 226 entry = priv->recv_msgs.next; 227 msg = list_entry(entry, struct ipmi_recv_msg, link); 228 list_del(entry); 229 spin_unlock_irqrestore(&priv->recv_msg_lock, flags); 230 231 addr_len = ipmi_addr_length(msg->addr.addr_type); 232 if (rsp->addr_len < addr_len) { 233 rv = -EINVAL; 234 goto recv_putback_on_err; 235 } 236 237 if (copy_to_user(rsp->addr, &msg->addr, addr_len)) { 238 rv = -EFAULT; 239 goto recv_putback_on_err; 240 } 241 rsp->addr_len = addr_len; 242 243 rsp->recv_type = msg->recv_type; 244 rsp->msgid = msg->msgid; 245 rsp->msg.netfn = msg->msg.netfn; 246 rsp->msg.cmd = msg->msg.cmd; 247 248 if (msg->msg.data_len > 0) { 249 if (rsp->msg.data_len < msg->msg.data_len) { 250 if (trunc) { 251 rv2 = -EMSGSIZE; 252 msg->msg.data_len = rsp->msg.data_len; 253 } else { 254 rv = -EMSGSIZE; 255 goto recv_putback_on_err; 256 } 257 } 258 259 if (copy_to_user(rsp->msg.data, 260 msg->msg.data, 261 msg->msg.data_len)) { 262 rv = -EFAULT; 263 goto recv_putback_on_err; 264 } 265 rsp->msg.data_len = msg->msg.data_len; 266 } else { 267 rsp->msg.data_len = 0; 268 } 269 270 rv = copyout(rsp, to); 271 if (rv) 272 goto recv_putback_on_err; 273 274 mutex_unlock(&priv->recv_mutex); 275 ipmi_free_recv_msg(msg); 276 return rv2; 277 278 recv_putback_on_err: 279 /* If we got an error, put the message back onto 280 the head of the queue. */ 281 spin_lock_irqsave(&priv->recv_msg_lock, flags); 282 list_add(entry, &priv->recv_msgs); 283 spin_unlock_irqrestore(&priv->recv_msg_lock, flags); 284 recv_err: 285 mutex_unlock(&priv->recv_mutex); 286 return rv; 287 } 288 289 static int copyout_recv(struct ipmi_recv *rsp, void __user *to) 290 { 291 return copy_to_user(to, rsp, sizeof(struct ipmi_recv)) ? -EFAULT : 0; 292 } 293 294 static long ipmi_ioctl(struct file *file, 295 unsigned int cmd, 296 unsigned long data) 297 { 298 int rv = -EINVAL; 299 struct ipmi_file_private *priv = file->private_data; 300 void __user *arg = (void __user *)data; 301 302 switch (cmd) 303 { 304 case IPMICTL_SEND_COMMAND: 305 { 306 struct ipmi_req req; 307 int retries; 308 unsigned int retry_time_ms; 309 310 if (copy_from_user(&req, arg, sizeof(req))) { 311 rv = -EFAULT; 312 break; 313 } 314 315 mutex_lock(&priv->recv_mutex); 316 retries = priv->default_retries; 317 retry_time_ms = priv->default_retry_time_ms; 318 mutex_unlock(&priv->recv_mutex); 319 320 rv = handle_send_req(priv->user, &req, retries, retry_time_ms); 321 break; 322 } 323 324 case IPMICTL_SEND_COMMAND_SETTIME: 325 { 326 struct ipmi_req_settime req; 327 328 if (copy_from_user(&req, arg, sizeof(req))) { 329 rv = -EFAULT; 330 break; 331 } 332 333 rv = handle_send_req(priv->user, 334 &req.req, 335 req.retries, 336 req.retry_time_ms); 337 break; 338 } 339 340 case IPMICTL_RECEIVE_MSG: 341 case IPMICTL_RECEIVE_MSG_TRUNC: 342 { 343 struct ipmi_recv rsp; 344 345 if (copy_from_user(&rsp, arg, sizeof(rsp))) 346 rv = -EFAULT; 347 else 348 rv = handle_recv(priv, cmd == IPMICTL_RECEIVE_MSG_TRUNC, 349 &rsp, copyout_recv, arg); 350 break; 351 } 352 353 case IPMICTL_REGISTER_FOR_CMD: 354 { 355 struct ipmi_cmdspec val; 356 357 if (copy_from_user(&val, arg, sizeof(val))) { 358 rv = -EFAULT; 359 break; 360 } 361 362 rv = ipmi_register_for_cmd(priv->user, val.netfn, val.cmd, 363 IPMI_CHAN_ALL); 364 break; 365 } 366 367 case IPMICTL_UNREGISTER_FOR_CMD: 368 { 369 struct ipmi_cmdspec val; 370 371 if (copy_from_user(&val, arg, sizeof(val))) { 372 rv = -EFAULT; 373 break; 374 } 375 376 rv = ipmi_unregister_for_cmd(priv->user, val.netfn, val.cmd, 377 IPMI_CHAN_ALL); 378 break; 379 } 380 381 case IPMICTL_REGISTER_FOR_CMD_CHANS: 382 { 383 struct ipmi_cmdspec_chans val; 384 385 if (copy_from_user(&val, arg, sizeof(val))) { 386 rv = -EFAULT; 387 break; 388 } 389 390 rv = ipmi_register_for_cmd(priv->user, val.netfn, val.cmd, 391 val.chans); 392 break; 393 } 394 395 case IPMICTL_UNREGISTER_FOR_CMD_CHANS: 396 { 397 struct ipmi_cmdspec_chans val; 398 399 if (copy_from_user(&val, arg, sizeof(val))) { 400 rv = -EFAULT; 401 break; 402 } 403 404 rv = ipmi_unregister_for_cmd(priv->user, val.netfn, val.cmd, 405 val.chans); 406 break; 407 } 408 409 case IPMICTL_SET_GETS_EVENTS_CMD: 410 { 411 int val; 412 413 if (copy_from_user(&val, arg, sizeof(val))) { 414 rv = -EFAULT; 415 break; 416 } 417 418 rv = ipmi_set_gets_events(priv->user, val); 419 break; 420 } 421 422 /* The next four are legacy, not per-channel. */ 423 case IPMICTL_SET_MY_ADDRESS_CMD: 424 { 425 unsigned int val; 426 427 if (copy_from_user(&val, arg, sizeof(val))) { 428 rv = -EFAULT; 429 break; 430 } 431 432 rv = ipmi_set_my_address(priv->user, 0, val); 433 break; 434 } 435 436 case IPMICTL_GET_MY_ADDRESS_CMD: 437 { 438 unsigned int val; 439 unsigned char rval; 440 441 rv = ipmi_get_my_address(priv->user, 0, &rval); 442 if (rv) 443 break; 444 445 val = rval; 446 447 if (copy_to_user(arg, &val, sizeof(val))) { 448 rv = -EFAULT; 449 break; 450 } 451 break; 452 } 453 454 case IPMICTL_SET_MY_LUN_CMD: 455 { 456 unsigned int val; 457 458 if (copy_from_user(&val, arg, sizeof(val))) { 459 rv = -EFAULT; 460 break; 461 } 462 463 rv = ipmi_set_my_LUN(priv->user, 0, val); 464 break; 465 } 466 467 case IPMICTL_GET_MY_LUN_CMD: 468 { 469 unsigned int val; 470 unsigned char rval; 471 472 rv = ipmi_get_my_LUN(priv->user, 0, &rval); 473 if (rv) 474 break; 475 476 val = rval; 477 478 if (copy_to_user(arg, &val, sizeof(val))) { 479 rv = -EFAULT; 480 break; 481 } 482 break; 483 } 484 485 case IPMICTL_SET_MY_CHANNEL_ADDRESS_CMD: 486 { 487 struct ipmi_channel_lun_address_set val; 488 489 if (copy_from_user(&val, arg, sizeof(val))) { 490 rv = -EFAULT; 491 break; 492 } 493 494 return ipmi_set_my_address(priv->user, val.channel, val.value); 495 } 496 497 case IPMICTL_GET_MY_CHANNEL_ADDRESS_CMD: 498 { 499 struct ipmi_channel_lun_address_set val; 500 501 if (copy_from_user(&val, arg, sizeof(val))) { 502 rv = -EFAULT; 503 break; 504 } 505 506 rv = ipmi_get_my_address(priv->user, val.channel, &val.value); 507 if (rv) 508 break; 509 510 if (copy_to_user(arg, &val, sizeof(val))) { 511 rv = -EFAULT; 512 break; 513 } 514 break; 515 } 516 517 case IPMICTL_SET_MY_CHANNEL_LUN_CMD: 518 { 519 struct ipmi_channel_lun_address_set val; 520 521 if (copy_from_user(&val, arg, sizeof(val))) { 522 rv = -EFAULT; 523 break; 524 } 525 526 rv = ipmi_set_my_LUN(priv->user, val.channel, val.value); 527 break; 528 } 529 530 case IPMICTL_GET_MY_CHANNEL_LUN_CMD: 531 { 532 struct ipmi_channel_lun_address_set val; 533 534 if (copy_from_user(&val, arg, sizeof(val))) { 535 rv = -EFAULT; 536 break; 537 } 538 539 rv = ipmi_get_my_LUN(priv->user, val.channel, &val.value); 540 if (rv) 541 break; 542 543 if (copy_to_user(arg, &val, sizeof(val))) { 544 rv = -EFAULT; 545 break; 546 } 547 break; 548 } 549 550 case IPMICTL_SET_TIMING_PARMS_CMD: 551 { 552 struct ipmi_timing_parms parms; 553 554 if (copy_from_user(&parms, arg, sizeof(parms))) { 555 rv = -EFAULT; 556 break; 557 } 558 559 mutex_lock(&priv->recv_mutex); 560 priv->default_retries = parms.retries; 561 priv->default_retry_time_ms = parms.retry_time_ms; 562 mutex_unlock(&priv->recv_mutex); 563 rv = 0; 564 break; 565 } 566 567 case IPMICTL_GET_TIMING_PARMS_CMD: 568 { 569 struct ipmi_timing_parms parms; 570 571 mutex_lock(&priv->recv_mutex); 572 parms.retries = priv->default_retries; 573 parms.retry_time_ms = priv->default_retry_time_ms; 574 mutex_unlock(&priv->recv_mutex); 575 576 if (copy_to_user(arg, &parms, sizeof(parms))) { 577 rv = -EFAULT; 578 break; 579 } 580 581 rv = 0; 582 break; 583 } 584 585 case IPMICTL_GET_MAINTENANCE_MODE_CMD: 586 { 587 int mode; 588 589 mode = ipmi_get_maintenance_mode(priv->user); 590 if (copy_to_user(arg, &mode, sizeof(mode))) { 591 rv = -EFAULT; 592 break; 593 } 594 rv = 0; 595 break; 596 } 597 598 case IPMICTL_SET_MAINTENANCE_MODE_CMD: 599 { 600 int mode; 601 602 if (copy_from_user(&mode, arg, sizeof(mode))) { 603 rv = -EFAULT; 604 break; 605 } 606 rv = ipmi_set_maintenance_mode(priv->user, mode); 607 break; 608 } 609 610 default: 611 rv = -ENOTTY; 612 break; 613 } 614 615 return rv; 616 } 617 618 #ifdef CONFIG_COMPAT 619 /* 620 * The following code contains code for supporting 32-bit compatible 621 * ioctls on 64-bit kernels. This allows running 32-bit apps on the 622 * 64-bit kernel 623 */ 624 #define COMPAT_IPMICTL_SEND_COMMAND \ 625 _IOR(IPMI_IOC_MAGIC, 13, struct compat_ipmi_req) 626 #define COMPAT_IPMICTL_SEND_COMMAND_SETTIME \ 627 _IOR(IPMI_IOC_MAGIC, 21, struct compat_ipmi_req_settime) 628 #define COMPAT_IPMICTL_RECEIVE_MSG \ 629 _IOWR(IPMI_IOC_MAGIC, 12, struct compat_ipmi_recv) 630 #define COMPAT_IPMICTL_RECEIVE_MSG_TRUNC \ 631 _IOWR(IPMI_IOC_MAGIC, 11, struct compat_ipmi_recv) 632 633 struct compat_ipmi_msg { 634 u8 netfn; 635 u8 cmd; 636 u16 data_len; 637 compat_uptr_t data; 638 }; 639 640 struct compat_ipmi_req { 641 compat_uptr_t addr; 642 compat_uint_t addr_len; 643 compat_long_t msgid; 644 struct compat_ipmi_msg msg; 645 }; 646 647 struct compat_ipmi_recv { 648 compat_int_t recv_type; 649 compat_uptr_t addr; 650 compat_uint_t addr_len; 651 compat_long_t msgid; 652 struct compat_ipmi_msg msg; 653 }; 654 655 struct compat_ipmi_req_settime { 656 struct compat_ipmi_req req; 657 compat_int_t retries; 658 compat_uint_t retry_time_ms; 659 }; 660 661 /* 662 * Define some helper functions for copying IPMI data 663 */ 664 static void get_compat_ipmi_msg(struct ipmi_msg *p64, 665 struct compat_ipmi_msg *p32) 666 { 667 p64->netfn = p32->netfn; 668 p64->cmd = p32->cmd; 669 p64->data_len = p32->data_len; 670 p64->data = compat_ptr(p32->data); 671 } 672 673 static void get_compat_ipmi_req(struct ipmi_req *p64, 674 struct compat_ipmi_req *p32) 675 { 676 p64->addr = compat_ptr(p32->addr); 677 p64->addr_len = p32->addr_len; 678 p64->msgid = p32->msgid; 679 get_compat_ipmi_msg(&p64->msg, &p32->msg); 680 } 681 682 static void get_compat_ipmi_req_settime(struct ipmi_req_settime *p64, 683 struct compat_ipmi_req_settime *p32) 684 { 685 get_compat_ipmi_req(&p64->req, &p32->req); 686 p64->retries = p32->retries; 687 p64->retry_time_ms = p32->retry_time_ms; 688 } 689 690 static void get_compat_ipmi_recv(struct ipmi_recv *p64, 691 struct compat_ipmi_recv *p32) 692 { 693 memset(p64, 0, sizeof(struct ipmi_recv)); 694 p64->recv_type = p32->recv_type; 695 p64->addr = compat_ptr(p32->addr); 696 p64->addr_len = p32->addr_len; 697 p64->msgid = p32->msgid; 698 get_compat_ipmi_msg(&p64->msg, &p32->msg); 699 } 700 701 static int copyout_recv32(struct ipmi_recv *p64, void __user *to) 702 { 703 struct compat_ipmi_recv v32; 704 memset(&v32, 0, sizeof(struct compat_ipmi_recv)); 705 v32.recv_type = p64->recv_type; 706 v32.addr = ptr_to_compat(p64->addr); 707 v32.addr_len = p64->addr_len; 708 v32.msgid = p64->msgid; 709 v32.msg.netfn = p64->msg.netfn; 710 v32.msg.cmd = p64->msg.cmd; 711 v32.msg.data_len = p64->msg.data_len; 712 v32.msg.data = ptr_to_compat(p64->msg.data); 713 return copy_to_user(to, &v32, sizeof(v32)) ? -EFAULT : 0; 714 } 715 716 /* 717 * Handle compatibility ioctls 718 */ 719 static long compat_ipmi_ioctl(struct file *filep, unsigned int cmd, 720 unsigned long arg) 721 { 722 struct ipmi_file_private *priv = filep->private_data; 723 724 switch(cmd) { 725 case COMPAT_IPMICTL_SEND_COMMAND: 726 { 727 struct ipmi_req rp; 728 struct compat_ipmi_req r32; 729 int retries; 730 unsigned int retry_time_ms; 731 732 if (copy_from_user(&r32, compat_ptr(arg), sizeof(r32))) 733 return -EFAULT; 734 735 get_compat_ipmi_req(&rp, &r32); 736 737 mutex_lock(&priv->recv_mutex); 738 retries = priv->default_retries; 739 retry_time_ms = priv->default_retry_time_ms; 740 mutex_unlock(&priv->recv_mutex); 741 742 return handle_send_req(priv->user, &rp, 743 retries, retry_time_ms); 744 } 745 case COMPAT_IPMICTL_SEND_COMMAND_SETTIME: 746 { 747 struct ipmi_req_settime sp; 748 struct compat_ipmi_req_settime sp32; 749 750 if (copy_from_user(&sp32, compat_ptr(arg), sizeof(sp32))) 751 return -EFAULT; 752 753 get_compat_ipmi_req_settime(&sp, &sp32); 754 755 return handle_send_req(priv->user, &sp.req, 756 sp.retries, sp.retry_time_ms); 757 } 758 case COMPAT_IPMICTL_RECEIVE_MSG: 759 case COMPAT_IPMICTL_RECEIVE_MSG_TRUNC: 760 { 761 struct ipmi_recv recv64; 762 struct compat_ipmi_recv recv32; 763 764 if (copy_from_user(&recv32, compat_ptr(arg), sizeof(recv32))) 765 return -EFAULT; 766 767 get_compat_ipmi_recv(&recv64, &recv32); 768 769 return handle_recv(priv, 770 cmd == COMPAT_IPMICTL_RECEIVE_MSG_TRUNC, 771 &recv64, copyout_recv32, compat_ptr(arg)); 772 } 773 default: 774 return ipmi_ioctl(filep, cmd, arg); 775 } 776 } 777 #endif 778 779 static const struct file_operations ipmi_fops = { 780 .owner = THIS_MODULE, 781 .unlocked_ioctl = ipmi_ioctl, 782 #ifdef CONFIG_COMPAT 783 .compat_ioctl = compat_ipmi_ioctl, 784 #endif 785 .open = ipmi_open, 786 .release = ipmi_release, 787 .fasync = ipmi_fasync, 788 .poll = ipmi_poll, 789 .llseek = noop_llseek, 790 }; 791 792 #define DEVICE_NAME "ipmidev" 793 794 static int ipmi_major; 795 module_param(ipmi_major, int, 0); 796 MODULE_PARM_DESC(ipmi_major, "Sets the major number of the IPMI device. By" 797 " default, or if you set it to zero, it will choose the next" 798 " available device. Setting it to -1 will disable the" 799 " interface. Other values will set the major device number" 800 " to that value."); 801 802 /* Keep track of the devices that are registered. */ 803 struct ipmi_reg_list { 804 dev_t dev; 805 struct list_head link; 806 }; 807 static LIST_HEAD(reg_list); 808 static DEFINE_MUTEX(reg_list_mutex); 809 810 static const struct class ipmi_class = { 811 .name = "ipmi", 812 }; 813 814 static void ipmi_new_smi(int if_num, struct device *device) 815 { 816 dev_t dev = MKDEV(ipmi_major, if_num); 817 struct ipmi_reg_list *entry; 818 819 entry = kmalloc(sizeof(*entry), GFP_KERNEL); 820 if (!entry) { 821 pr_err("ipmi_devintf: Unable to create the ipmi class device link\n"); 822 return; 823 } 824 entry->dev = dev; 825 826 mutex_lock(®_list_mutex); 827 device_create(&ipmi_class, device, dev, NULL, "ipmi%d", if_num); 828 list_add(&entry->link, ®_list); 829 mutex_unlock(®_list_mutex); 830 } 831 832 static void ipmi_smi_gone(int if_num) 833 { 834 dev_t dev = MKDEV(ipmi_major, if_num); 835 struct ipmi_reg_list *entry; 836 837 mutex_lock(®_list_mutex); 838 list_for_each_entry(entry, ®_list, link) { 839 if (entry->dev == dev) { 840 list_del(&entry->link); 841 kfree(entry); 842 break; 843 } 844 } 845 device_destroy(&ipmi_class, dev); 846 mutex_unlock(®_list_mutex); 847 } 848 849 static struct ipmi_smi_watcher smi_watcher = 850 { 851 .owner = THIS_MODULE, 852 .new_smi = ipmi_new_smi, 853 .smi_gone = ipmi_smi_gone, 854 }; 855 856 static int __init init_ipmi_devintf(void) 857 { 858 int rv; 859 860 if (ipmi_major < 0) 861 return -EINVAL; 862 863 pr_info("ipmi device interface\n"); 864 865 rv = class_register(&ipmi_class); 866 if (rv) 867 return rv; 868 869 rv = register_chrdev(ipmi_major, DEVICE_NAME, &ipmi_fops); 870 if (rv < 0) { 871 class_unregister(&ipmi_class); 872 pr_err("ipmi: can't get major %d\n", ipmi_major); 873 return rv; 874 } 875 876 if (ipmi_major == 0) { 877 ipmi_major = rv; 878 } 879 880 rv = ipmi_smi_watcher_register(&smi_watcher); 881 if (rv) { 882 unregister_chrdev(ipmi_major, DEVICE_NAME); 883 class_unregister(&ipmi_class); 884 pr_warn("ipmi: can't register smi watcher\n"); 885 return rv; 886 } 887 888 return 0; 889 } 890 module_init(init_ipmi_devintf); 891 892 static void __exit cleanup_ipmi(void) 893 { 894 struct ipmi_reg_list *entry, *entry2; 895 mutex_lock(®_list_mutex); 896 list_for_each_entry_safe(entry, entry2, ®_list, link) { 897 list_del(&entry->link); 898 device_destroy(&ipmi_class, entry->dev); 899 kfree(entry); 900 } 901 mutex_unlock(®_list_mutex); 902 class_unregister(&ipmi_class); 903 ipmi_smi_watcher_unregister(&smi_watcher); 904 unregister_chrdev(ipmi_major, DEVICE_NAME); 905 } 906 module_exit(cleanup_ipmi); 907 908 MODULE_LICENSE("GPL"); 909 MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>"); 910 MODULE_DESCRIPTION("Linux device interface for the IPMI message handler."); 911