1 /* 2 * Copyright (c) 2009 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Alex Hornung <ahornung@gmail.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/kernel.h> 37 #include <sys/mount.h> 38 #include <sys/vnode.h> 39 #include <sys/types.h> 40 #include <sys/lock.h> 41 #include <sys/msgport.h> 42 #include <sys/sysctl.h> 43 #include <sys/ucred.h> 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/devfs.h> 47 #include <sys/devfs_rules.h> 48 #include <sys/udev.h> 49 50 #include <sys/msgport2.h> 51 #include <sys/spinlock2.h> 52 #include <sys/mplock2.h> 53 #include <sys/sysref2.h> 54 55 MALLOC_DEFINE(M_DEVFS, "devfs", "Device File System (devfs) allocations"); 56 DEVFS_DECLARE_CLONE_BITMAP(ops_id); 57 /* 58 * SYSREF Integration - reference counting, allocation, 59 * sysid and syslink integration. 60 */ 61 static void devfs_cdev_terminate(cdev_t dev); 62 static void devfs_cdev_lock(cdev_t dev); 63 static void devfs_cdev_unlock(cdev_t dev); 64 static struct sysref_class cdev_sysref_class = { 65 .name = "cdev", 66 .mtype = M_DEVFS, 67 .proto = SYSREF_PROTO_DEV, 68 .offset = offsetof(struct cdev, si_sysref), 69 .objsize = sizeof(struct cdev), 70 .mag_capacity = 32, 71 .flags = 0, 72 .ops = { 73 .terminate = (sysref_terminate_func_t)devfs_cdev_terminate, 74 .lock = (sysref_lock_func_t)devfs_cdev_lock, 75 .unlock = (sysref_unlock_func_t)devfs_cdev_unlock 76 } 77 }; 78 79 static struct objcache *devfs_node_cache; 80 static struct objcache *devfs_msg_cache; 81 static struct objcache *devfs_dev_cache; 82 83 static struct objcache_malloc_args devfs_node_malloc_args = { 84 sizeof(struct devfs_node), M_DEVFS }; 85 struct objcache_malloc_args devfs_msg_malloc_args = { 86 sizeof(struct devfs_msg), M_DEVFS }; 87 struct objcache_malloc_args devfs_dev_malloc_args = { 88 sizeof(struct cdev), M_DEVFS }; 89 90 static struct devfs_dev_head devfs_dev_list = 91 TAILQ_HEAD_INITIALIZER(devfs_dev_list); 92 static struct devfs_mnt_head devfs_mnt_list = 93 TAILQ_HEAD_INITIALIZER(devfs_mnt_list); 94 static struct devfs_chandler_head devfs_chandler_list = 95 TAILQ_HEAD_INITIALIZER(devfs_chandler_list); 96 static struct devfs_alias_head devfs_alias_list = 97 TAILQ_HEAD_INITIALIZER(devfs_alias_list); 98 static struct devfs_dev_ops_head devfs_dev_ops_list = 99 TAILQ_HEAD_INITIALIZER(devfs_dev_ops_list); 100 101 struct lock devfs_lock; 102 static struct lwkt_port devfs_dispose_port; 103 static struct lwkt_port devfs_msg_port; 104 static struct thread *td_core; 105 106 static struct spinlock ino_lock; 107 static ino_t d_ino; 108 static int devfs_debug_enable; 109 static int devfs_run; 110 111 static ino_t devfs_fetch_ino(void); 112 static int devfs_create_all_dev_worker(struct devfs_node *); 113 static int devfs_create_dev_worker(cdev_t, uid_t, gid_t, int); 114 static int devfs_destroy_dev_worker(cdev_t); 115 static int devfs_destroy_subnames_worker(char *); 116 static int devfs_destroy_dev_by_ops_worker(struct dev_ops *, int); 117 static int devfs_propagate_dev(cdev_t, int); 118 static int devfs_unlink_dev(cdev_t dev); 119 static void devfs_msg_exec(devfs_msg_t msg); 120 121 static int devfs_chandler_add_worker(const char *, d_clone_t *); 122 static int devfs_chandler_del_worker(const char *); 123 124 static void devfs_msg_autofree_reply(lwkt_port_t, lwkt_msg_t); 125 static void devfs_msg_core(void *); 126 127 static int devfs_find_device_by_name_worker(devfs_msg_t); 128 static int devfs_find_device_by_udev_worker(devfs_msg_t); 129 130 static int devfs_apply_reset_rules_caller(char *, int); 131 132 static int devfs_scan_callback_worker(devfs_scan_t *, void *); 133 134 static struct devfs_node *devfs_resolve_or_create_dir(struct devfs_node *, 135 char *, size_t, int); 136 137 static int devfs_make_alias_worker(struct devfs_alias *); 138 static int devfs_destroy_alias_worker(struct devfs_alias *); 139 static int devfs_alias_remove(cdev_t); 140 static int devfs_alias_reap(void); 141 static int devfs_alias_propagate(struct devfs_alias *, int); 142 static int devfs_alias_apply(struct devfs_node *, struct devfs_alias *); 143 static int devfs_alias_check_create(struct devfs_node *); 144 145 static int devfs_clr_subnames_flag_worker(char *, uint32_t); 146 static int devfs_destroy_subnames_without_flag_worker(char *, uint32_t); 147 148 static void *devfs_reaperp_callback(struct devfs_node *, void *); 149 static void *devfs_gc_dirs_callback(struct devfs_node *, void *); 150 static void *devfs_gc_links_callback(struct devfs_node *, struct devfs_node *); 151 static void * 152 devfs_inode_to_vnode_worker_callback(struct devfs_node *, ino_t *); 153 154 /* 155 * devfs_debug() is a SYSCTL and TUNABLE controlled debug output function 156 * using kvprintf 157 */ 158 int 159 devfs_debug(int level, char *fmt, ...) 160 { 161 __va_list ap; 162 163 __va_start(ap, fmt); 164 if (level <= devfs_debug_enable) 165 kvprintf(fmt, ap); 166 __va_end(ap); 167 168 return 0; 169 } 170 171 /* 172 * devfs_allocp() Allocates a new devfs node with the specified 173 * parameters. The node is also automatically linked into the topology 174 * if a parent is specified. It also calls the rule and alias stuff to 175 * be applied on the new node 176 */ 177 struct devfs_node * 178 devfs_allocp(devfs_nodetype devfsnodetype, char *name, 179 struct devfs_node *parent, struct mount *mp, cdev_t dev) 180 { 181 struct devfs_node *node = NULL; 182 size_t namlen = strlen(name); 183 184 node = objcache_get(devfs_node_cache, M_WAITOK); 185 bzero(node, sizeof(*node)); 186 187 atomic_add_long(&DEVFS_MNTDATA(mp)->leak_count, 1); 188 189 node->d_dev = NULL; 190 node->nchildren = 1; 191 node->mp = mp; 192 node->d_dir.d_ino = devfs_fetch_ino(); 193 194 /* 195 * Cookie jar for children. Leave 0 and 1 for '.' and '..' entries 196 * respectively. 197 */ 198 node->cookie_jar = 2; 199 200 /* 201 * Access Control members 202 */ 203 node->mode = DEVFS_DEFAULT_MODE; 204 node->uid = DEVFS_DEFAULT_UID; 205 node->gid = DEVFS_DEFAULT_GID; 206 207 switch (devfsnodetype) { 208 case Proot: 209 /* 210 * Ensure that we don't recycle the root vnode by marking it as 211 * linked into the topology. 212 */ 213 node->flags |= DEVFS_NODE_LINKED; 214 case Pdir: 215 TAILQ_INIT(DEVFS_DENODE_HEAD(node)); 216 node->d_dir.d_type = DT_DIR; 217 node->nchildren = 2; 218 break; 219 220 case Plink: 221 node->d_dir.d_type = DT_LNK; 222 break; 223 224 case Preg: 225 node->d_dir.d_type = DT_REG; 226 break; 227 228 case Pdev: 229 if (dev != NULL) { 230 node->d_dir.d_type = DT_CHR; 231 node->d_dev = dev; 232 233 node->mode = dev->si_perms; 234 node->uid = dev->si_uid; 235 node->gid = dev->si_gid; 236 237 devfs_alias_check_create(node); 238 } 239 break; 240 241 default: 242 panic("devfs_allocp: unknown node type"); 243 } 244 245 node->v_node = NULL; 246 node->node_type = devfsnodetype; 247 248 /* Initialize the dirent structure of each devfs vnode */ 249 node->d_dir.d_namlen = namlen; 250 node->d_dir.d_name = kmalloc(namlen+1, M_DEVFS, M_WAITOK); 251 memcpy(node->d_dir.d_name, name, namlen); 252 node->d_dir.d_name[namlen] = '\0'; 253 254 /* Initialize the parent node element */ 255 node->parent = parent; 256 257 /* Initialize *time members */ 258 nanotime(&node->atime); 259 node->mtime = node->ctime = node->atime; 260 261 /* 262 * Associate with parent as last step, clean out namecache 263 * reference. 264 */ 265 if ((parent != NULL) && 266 ((parent->node_type == Proot) || (parent->node_type == Pdir))) { 267 parent->nchildren++; 268 node->cookie = parent->cookie_jar++; 269 node->flags |= DEVFS_NODE_LINKED; 270 TAILQ_INSERT_TAIL(DEVFS_DENODE_HEAD(parent), node, link); 271 272 /* This forces negative namecache lookups to clear */ 273 ++mp->mnt_namecache_gen; 274 } 275 276 /* Apply rules */ 277 devfs_rule_check_apply(node, NULL); 278 279 atomic_add_long(&DEVFS_MNTDATA(mp)->file_count, 1); 280 281 return node; 282 } 283 284 /* 285 * devfs_allocv() allocates a new vnode based on a devfs node. 286 */ 287 int 288 devfs_allocv(struct vnode **vpp, struct devfs_node *node) 289 { 290 struct vnode *vp; 291 int error = 0; 292 293 KKASSERT(node); 294 295 try_again: 296 while ((vp = node->v_node) != NULL) { 297 error = vget(vp, LK_EXCLUSIVE); 298 if (error != ENOENT) { 299 *vpp = vp; 300 goto out; 301 } 302 } 303 304 if ((error = getnewvnode(VT_DEVFS, node->mp, vpp, 0, 0)) != 0) 305 goto out; 306 307 vp = *vpp; 308 309 if (node->v_node != NULL) { 310 vp->v_type = VBAD; 311 vx_put(vp); 312 goto try_again; 313 } 314 315 vp->v_data = node; 316 node->v_node = vp; 317 318 switch (node->node_type) { 319 case Proot: 320 vsetflags(vp, VROOT); 321 /* fall through */ 322 case Pdir: 323 vp->v_type = VDIR; 324 break; 325 326 case Plink: 327 vp->v_type = VLNK; 328 break; 329 330 case Preg: 331 vp->v_type = VREG; 332 break; 333 334 case Pdev: 335 vp->v_type = VCHR; 336 KKASSERT(node->d_dev); 337 338 vp->v_uminor = node->d_dev->si_uminor; 339 vp->v_umajor = 0; 340 341 v_associate_rdev(vp, node->d_dev); 342 vp->v_ops = &node->mp->mnt_vn_spec_ops; 343 break; 344 345 default: 346 panic("devfs_allocv: unknown node type"); 347 } 348 349 out: 350 return error; 351 } 352 353 /* 354 * devfs_allocvp allocates both a devfs node (with the given settings) and a vnode 355 * based on the newly created devfs node. 356 */ 357 int 358 devfs_allocvp(struct mount *mp, struct vnode **vpp, devfs_nodetype devfsnodetype, 359 char *name, struct devfs_node *parent, cdev_t dev) 360 { 361 struct devfs_node *node; 362 363 node = devfs_allocp(devfsnodetype, name, parent, mp, dev); 364 365 if (node != NULL) 366 devfs_allocv(vpp, node); 367 else 368 *vpp = NULL; 369 370 return 0; 371 } 372 373 /* 374 * Destroy the devfs_node. The node must be unlinked from the topology. 375 * 376 * This function will also destroy any vnode association with the node 377 * and device. 378 * 379 * The cdev_t itself remains intact. 380 * 381 * The core lock is not necessarily held on call and must be temporarily 382 * released if it is to avoid a deadlock. 383 */ 384 int 385 devfs_freep(struct devfs_node *node) 386 { 387 struct vnode *vp; 388 int relock; 389 390 KKASSERT(node); 391 KKASSERT(((node->flags & DEVFS_NODE_LINKED) == 0) || 392 (node->node_type == Proot)); 393 394 /* 395 * Protect against double frees 396 */ 397 KKASSERT((node->flags & DEVFS_DESTROYED) == 0); 398 node->flags |= DEVFS_DESTROYED; 399 400 /* 401 * Avoid deadlocks between devfs_lock and the vnode lock when 402 * disassociating the vnode (stress2 pty vs ls -la /dev/pts). 403 * 404 * This also prevents the vnode reclaim code from double-freeing 405 * the node. The vget() is required to safely modified the vp 406 * and cycle the refs to terminate an inactive vp. 407 */ 408 if (lockstatus(&devfs_lock, curthread) == LK_EXCLUSIVE) { 409 lockmgr(&devfs_lock, LK_RELEASE); 410 relock = 1; 411 } else { 412 relock = 0; 413 } 414 415 while ((vp = node->v_node) != NULL) { 416 if (vget(vp, LK_EXCLUSIVE | LK_RETRY) != 0) 417 break; 418 v_release_rdev(vp); 419 vp->v_data = NULL; 420 node->v_node = NULL; 421 cache_inval_vp(vp, CINV_DESTROY); 422 vput(vp); 423 } 424 425 /* 426 * Remaining cleanup 427 */ 428 atomic_subtract_long(&DEVFS_MNTDATA(node->mp)->leak_count, 1); 429 if (node->symlink_name) { 430 kfree(node->symlink_name, M_DEVFS); 431 node->symlink_name = NULL; 432 } 433 434 /* 435 * Remove the node from the orphan list if it is still on it. 436 */ 437 if (node->flags & DEVFS_ORPHANED) 438 devfs_tracer_del_orphan(node); 439 440 if (node->d_dir.d_name) { 441 kfree(node->d_dir.d_name, M_DEVFS); 442 node->d_dir.d_name = NULL; 443 } 444 atomic_subtract_long(&DEVFS_MNTDATA(node->mp)->file_count, 1); 445 objcache_put(devfs_node_cache, node); 446 447 if (relock) 448 lockmgr(&devfs_lock, LK_EXCLUSIVE); 449 450 return 0; 451 } 452 453 /* 454 * Unlink the devfs node from the topology and add it to the orphan list. 455 * The node will later be destroyed by freep. 456 * 457 * Any vnode association, including the v_rdev and v_data, remains intact 458 * until the freep. 459 */ 460 int 461 devfs_unlinkp(struct devfs_node *node) 462 { 463 struct devfs_node *parent; 464 KKASSERT(node); 465 466 /* 467 * Add the node to the orphan list, so it is referenced somewhere, to 468 * so we don't leak it. 469 */ 470 devfs_tracer_add_orphan(node); 471 472 parent = node->parent; 473 474 /* 475 * If the parent is known we can unlink the node out of the topology 476 */ 477 if (parent) { 478 TAILQ_REMOVE(DEVFS_DENODE_HEAD(parent), node, link); 479 parent->nchildren--; 480 node->flags &= ~DEVFS_NODE_LINKED; 481 } 482 483 node->parent = NULL; 484 return 0; 485 } 486 487 void * 488 devfs_iterate_topology(struct devfs_node *node, 489 devfs_iterate_callback_t *callback, void *arg1) 490 { 491 struct devfs_node *node1, *node2; 492 void *ret = NULL; 493 494 if ((node->node_type == Proot) || (node->node_type == Pdir)) { 495 if (node->nchildren > 2) { 496 TAILQ_FOREACH_MUTABLE(node1, DEVFS_DENODE_HEAD(node), 497 link, node2) { 498 if ((ret = devfs_iterate_topology(node1, callback, arg1))) 499 return ret; 500 } 501 } 502 } 503 504 ret = callback(node, arg1); 505 return ret; 506 } 507 508 /* 509 * devfs_reaperp() is a recursive function that iterates through all the 510 * topology, unlinking and freeing all devfs nodes. 511 */ 512 static void * 513 devfs_reaperp_callback(struct devfs_node *node, void *unused) 514 { 515 devfs_unlinkp(node); 516 devfs_freep(node); 517 518 return NULL; 519 } 520 521 static void * 522 devfs_gc_dirs_callback(struct devfs_node *node, void *unused) 523 { 524 if (node->node_type == Pdir) { 525 if ((node->nchildren == 2) && 526 !(node->flags & DEVFS_USER_CREATED)) { 527 devfs_unlinkp(node); 528 devfs_freep(node); 529 } 530 } 531 532 return NULL; 533 } 534 535 static void * 536 devfs_gc_links_callback(struct devfs_node *node, struct devfs_node *target) 537 { 538 if ((node->node_type == Plink) && (node->link_target == target)) { 539 devfs_unlinkp(node); 540 devfs_freep(node); 541 } 542 543 return NULL; 544 } 545 546 /* 547 * devfs_gc() is devfs garbage collector. It takes care of unlinking and 548 * freeing a node, but also removes empty directories and links that link 549 * via devfs auto-link mechanism to the node being deleted. 550 */ 551 int 552 devfs_gc(struct devfs_node *node) 553 { 554 struct devfs_node *root_node = DEVFS_MNTDATA(node->mp)->root_node; 555 556 if (node->nlinks > 0) 557 devfs_iterate_topology(root_node, 558 (devfs_iterate_callback_t *)devfs_gc_links_callback, node); 559 560 devfs_unlinkp(node); 561 devfs_iterate_topology(root_node, 562 (devfs_iterate_callback_t *)devfs_gc_dirs_callback, NULL); 563 564 devfs_freep(node); 565 566 return 0; 567 } 568 569 /* 570 * devfs_create_dev() is the asynchronous entry point for device creation. 571 * It just sends a message with the relevant details to the devfs core. 572 * 573 * This function will reference the passed device. The reference is owned 574 * by devfs and represents all of the device's node associations. 575 */ 576 int 577 devfs_create_dev(cdev_t dev, uid_t uid, gid_t gid, int perms) 578 { 579 reference_dev(dev); 580 devfs_msg_send_dev(DEVFS_DEVICE_CREATE, dev, uid, gid, perms); 581 582 return 0; 583 } 584 585 /* 586 * devfs_destroy_dev() is the asynchronous entry point for device destruction. 587 * It just sends a message with the relevant details to the devfs core. 588 */ 589 int 590 devfs_destroy_dev(cdev_t dev) 591 { 592 devfs_msg_send_dev(DEVFS_DEVICE_DESTROY, dev, 0, 0, 0); 593 return 0; 594 } 595 596 /* 597 * devfs_mount_add() is the synchronous entry point for adding a new devfs 598 * mount. It sends a synchronous message with the relevant details to the 599 * devfs core. 600 */ 601 int 602 devfs_mount_add(struct devfs_mnt_data *mnt) 603 { 604 devfs_msg_t msg; 605 606 msg = devfs_msg_get(); 607 msg->mdv_mnt = mnt; 608 msg = devfs_msg_send_sync(DEVFS_MOUNT_ADD, msg); 609 devfs_msg_put(msg); 610 611 return 0; 612 } 613 614 /* 615 * devfs_mount_del() is the synchronous entry point for removing a devfs mount. 616 * It sends a synchronous message with the relevant details to the devfs core. 617 */ 618 int 619 devfs_mount_del(struct devfs_mnt_data *mnt) 620 { 621 devfs_msg_t msg; 622 623 msg = devfs_msg_get(); 624 msg->mdv_mnt = mnt; 625 msg = devfs_msg_send_sync(DEVFS_MOUNT_DEL, msg); 626 devfs_msg_put(msg); 627 628 return 0; 629 } 630 631 /* 632 * devfs_destroy_subnames() is the synchronous entry point for device 633 * destruction by subname. It just sends a message with the relevant details to 634 * the devfs core. 635 */ 636 int 637 devfs_destroy_subnames(char *name) 638 { 639 devfs_msg_t msg; 640 641 msg = devfs_msg_get(); 642 msg->mdv_load = name; 643 msg = devfs_msg_send_sync(DEVFS_DESTROY_SUBNAMES, msg); 644 devfs_msg_put(msg); 645 return 0; 646 } 647 648 int 649 devfs_clr_subnames_flag(char *name, uint32_t flag) 650 { 651 devfs_msg_t msg; 652 653 msg = devfs_msg_get(); 654 msg->mdv_flags.name = name; 655 msg->mdv_flags.flag = flag; 656 msg = devfs_msg_send_sync(DEVFS_CLR_SUBNAMES_FLAG, msg); 657 devfs_msg_put(msg); 658 659 return 0; 660 } 661 662 int 663 devfs_destroy_subnames_without_flag(char *name, uint32_t flag) 664 { 665 devfs_msg_t msg; 666 667 msg = devfs_msg_get(); 668 msg->mdv_flags.name = name; 669 msg->mdv_flags.flag = flag; 670 msg = devfs_msg_send_sync(DEVFS_DESTROY_SUBNAMES_WO_FLAG, msg); 671 devfs_msg_put(msg); 672 673 return 0; 674 } 675 676 /* 677 * devfs_create_all_dev is the asynchronous entry point to trigger device 678 * node creation. It just sends a message with the relevant details to 679 * the devfs core. 680 */ 681 int 682 devfs_create_all_dev(struct devfs_node *root) 683 { 684 devfs_msg_send_generic(DEVFS_CREATE_ALL_DEV, root); 685 return 0; 686 } 687 688 /* 689 * devfs_destroy_dev_by_ops is the asynchronous entry point to destroy all 690 * devices with a specific set of dev_ops and minor. It just sends a 691 * message with the relevant details to the devfs core. 692 */ 693 int 694 devfs_destroy_dev_by_ops(struct dev_ops *ops, int minor) 695 { 696 devfs_msg_send_ops(DEVFS_DESTROY_DEV_BY_OPS, ops, minor); 697 return 0; 698 } 699 700 /* 701 * devfs_clone_handler_add is the synchronous entry point to add a new 702 * clone handler. It just sends a message with the relevant details to 703 * the devfs core. 704 */ 705 int 706 devfs_clone_handler_add(const char *name, d_clone_t *nhandler) 707 { 708 devfs_msg_t msg; 709 710 msg = devfs_msg_get(); 711 msg->mdv_chandler.name = name; 712 msg->mdv_chandler.nhandler = nhandler; 713 msg = devfs_msg_send_sync(DEVFS_CHANDLER_ADD, msg); 714 devfs_msg_put(msg); 715 return 0; 716 } 717 718 /* 719 * devfs_clone_handler_del is the synchronous entry point to remove a 720 * clone handler. It just sends a message with the relevant details to 721 * the devfs core. 722 */ 723 int 724 devfs_clone_handler_del(const char *name) 725 { 726 devfs_msg_t msg; 727 728 msg = devfs_msg_get(); 729 msg->mdv_chandler.name = name; 730 msg->mdv_chandler.nhandler = NULL; 731 msg = devfs_msg_send_sync(DEVFS_CHANDLER_DEL, msg); 732 devfs_msg_put(msg); 733 return 0; 734 } 735 736 /* 737 * devfs_find_device_by_name is the synchronous entry point to find a 738 * device given its name. It sends a synchronous message with the 739 * relevant details to the devfs core and returns the answer. 740 */ 741 cdev_t 742 devfs_find_device_by_name(const char *fmt, ...) 743 { 744 cdev_t found = NULL; 745 devfs_msg_t msg; 746 char *target; 747 __va_list ap; 748 749 if (fmt == NULL) 750 return NULL; 751 752 __va_start(ap, fmt); 753 kvasnrprintf(&target, PATH_MAX, 10, fmt, ap); 754 __va_end(ap); 755 756 msg = devfs_msg_get(); 757 msg->mdv_name = target; 758 msg = devfs_msg_send_sync(DEVFS_FIND_DEVICE_BY_NAME, msg); 759 found = msg->mdv_cdev; 760 devfs_msg_put(msg); 761 kvasfree(&target); 762 763 return found; 764 } 765 766 /* 767 * devfs_find_device_by_udev is the synchronous entry point to find a 768 * device given its udev number. It sends a synchronous message with 769 * the relevant details to the devfs core and returns the answer. 770 */ 771 cdev_t 772 devfs_find_device_by_udev(udev_t udev) 773 { 774 cdev_t found = NULL; 775 devfs_msg_t msg; 776 777 msg = devfs_msg_get(); 778 msg->mdv_udev = udev; 779 msg = devfs_msg_send_sync(DEVFS_FIND_DEVICE_BY_UDEV, msg); 780 found = msg->mdv_cdev; 781 devfs_msg_put(msg); 782 783 devfs_debug(DEVFS_DEBUG_DEBUG, 784 "devfs_find_device_by_udev found? %s -end:3-\n", 785 ((found) ? found->si_name:"NO")); 786 return found; 787 } 788 789 struct vnode * 790 devfs_inode_to_vnode(struct mount *mp, ino_t target) 791 { 792 struct vnode *vp = NULL; 793 devfs_msg_t msg; 794 795 if (mp == NULL) 796 return NULL; 797 798 msg = devfs_msg_get(); 799 msg->mdv_ino.mp = mp; 800 msg->mdv_ino.ino = target; 801 msg = devfs_msg_send_sync(DEVFS_INODE_TO_VNODE, msg); 802 vp = msg->mdv_ino.vp; 803 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 804 devfs_msg_put(msg); 805 806 return vp; 807 } 808 809 /* 810 * devfs_make_alias is the asynchronous entry point to register an alias 811 * for a device. It just sends a message with the relevant details to the 812 * devfs core. 813 */ 814 int 815 devfs_make_alias(const char *name, cdev_t dev_target) 816 { 817 struct devfs_alias *alias; 818 size_t len; 819 820 len = strlen(name); 821 822 alias = kmalloc(sizeof(struct devfs_alias), M_DEVFS, M_WAITOK); 823 alias->name = kstrdup(name, M_DEVFS); 824 alias->namlen = len; 825 alias->dev_target = dev_target; 826 827 devfs_msg_send_generic(DEVFS_MAKE_ALIAS, alias); 828 return 0; 829 } 830 831 /* 832 * devfs_destroy_alias is the asynchronous entry point to deregister an alias 833 * for a device. It just sends a message with the relevant details to the 834 * devfs core. 835 */ 836 int 837 devfs_destroy_alias(const char *name, cdev_t dev_target) 838 { 839 struct devfs_alias *alias; 840 size_t len; 841 842 len = strlen(name); 843 844 alias = kmalloc(sizeof(struct devfs_alias), M_DEVFS, M_WAITOK); 845 alias->name = kstrdup(name, M_DEVFS); 846 alias->namlen = len; 847 alias->dev_target = dev_target; 848 849 devfs_msg_send_generic(DEVFS_DESTROY_ALIAS, alias); 850 return 0; 851 } 852 853 /* 854 * devfs_apply_rules is the asynchronous entry point to trigger application 855 * of all rules. It just sends a message with the relevant details to the 856 * devfs core. 857 */ 858 int 859 devfs_apply_rules(char *mntto) 860 { 861 char *new_name; 862 863 new_name = kstrdup(mntto, M_DEVFS); 864 devfs_msg_send_name(DEVFS_APPLY_RULES, new_name); 865 866 return 0; 867 } 868 869 /* 870 * devfs_reset_rules is the asynchronous entry point to trigger reset of all 871 * rules. It just sends a message with the relevant details to the devfs core. 872 */ 873 int 874 devfs_reset_rules(char *mntto) 875 { 876 char *new_name; 877 878 new_name = kstrdup(mntto, M_DEVFS); 879 devfs_msg_send_name(DEVFS_RESET_RULES, new_name); 880 881 return 0; 882 } 883 884 885 /* 886 * devfs_scan_callback is the asynchronous entry point to call a callback 887 * on all cdevs. 888 * It just sends a message with the relevant details to the devfs core. 889 */ 890 int 891 devfs_scan_callback(devfs_scan_t *callback, void *arg) 892 { 893 devfs_msg_t msg; 894 895 KKASSERT(sizeof(callback) == sizeof(void *)); 896 897 msg = devfs_msg_get(); 898 msg->mdv_load = callback; 899 msg->mdv_load2 = arg; 900 msg = devfs_msg_send_sync(DEVFS_SCAN_CALLBACK, msg); 901 devfs_msg_put(msg); 902 903 return 0; 904 } 905 906 907 /* 908 * Acts as a message drain. Any message that is replied to here gets destroyed 909 * and the memory freed. 910 */ 911 static void 912 devfs_msg_autofree_reply(lwkt_port_t port, lwkt_msg_t msg) 913 { 914 devfs_msg_put((devfs_msg_t)msg); 915 } 916 917 /* 918 * devfs_msg_get allocates a new devfs msg and returns it. 919 */ 920 devfs_msg_t 921 devfs_msg_get(void) 922 { 923 return objcache_get(devfs_msg_cache, M_WAITOK); 924 } 925 926 /* 927 * devfs_msg_put deallocates a given devfs msg. 928 */ 929 int 930 devfs_msg_put(devfs_msg_t msg) 931 { 932 objcache_put(devfs_msg_cache, msg); 933 return 0; 934 } 935 936 /* 937 * devfs_msg_send is the generic asynchronous message sending facility 938 * for devfs. By default the reply port is the automatic disposal port. 939 * 940 * If the current thread is the devfs_msg_port thread we execute the 941 * operation synchronously. 942 */ 943 void 944 devfs_msg_send(uint32_t cmd, devfs_msg_t devfs_msg) 945 { 946 lwkt_port_t port = &devfs_msg_port; 947 948 lwkt_initmsg(&devfs_msg->hdr, &devfs_dispose_port, 0); 949 950 devfs_msg->hdr.u.ms_result = cmd; 951 952 if (port->mpu_td == curthread) { 953 devfs_msg_exec(devfs_msg); 954 lwkt_replymsg(&devfs_msg->hdr, 0); 955 } else { 956 lwkt_sendmsg(port, (lwkt_msg_t)devfs_msg); 957 } 958 } 959 960 /* 961 * devfs_msg_send_sync is the generic synchronous message sending 962 * facility for devfs. It initializes a local reply port and waits 963 * for the core's answer. This answer is then returned. 964 */ 965 devfs_msg_t 966 devfs_msg_send_sync(uint32_t cmd, devfs_msg_t devfs_msg) 967 { 968 struct lwkt_port rep_port; 969 devfs_msg_t msg_incoming; 970 lwkt_port_t port = &devfs_msg_port; 971 972 lwkt_initport_thread(&rep_port, curthread); 973 lwkt_initmsg(&devfs_msg->hdr, &rep_port, 0); 974 975 devfs_msg->hdr.u.ms_result = cmd; 976 977 lwkt_sendmsg(port, (lwkt_msg_t)devfs_msg); 978 msg_incoming = lwkt_waitport(&rep_port, 0); 979 980 return msg_incoming; 981 } 982 983 /* 984 * sends a message with a generic argument. 985 */ 986 void 987 devfs_msg_send_generic(uint32_t cmd, void *load) 988 { 989 devfs_msg_t devfs_msg = devfs_msg_get(); 990 991 devfs_msg->mdv_load = load; 992 devfs_msg_send(cmd, devfs_msg); 993 } 994 995 /* 996 * sends a message with a name argument. 997 */ 998 void 999 devfs_msg_send_name(uint32_t cmd, char *name) 1000 { 1001 devfs_msg_t devfs_msg = devfs_msg_get(); 1002 1003 devfs_msg->mdv_name = name; 1004 devfs_msg_send(cmd, devfs_msg); 1005 } 1006 1007 /* 1008 * sends a message with a mount argument. 1009 */ 1010 void 1011 devfs_msg_send_mount(uint32_t cmd, struct devfs_mnt_data *mnt) 1012 { 1013 devfs_msg_t devfs_msg = devfs_msg_get(); 1014 1015 devfs_msg->mdv_mnt = mnt; 1016 devfs_msg_send(cmd, devfs_msg); 1017 } 1018 1019 /* 1020 * sends a message with an ops argument. 1021 */ 1022 void 1023 devfs_msg_send_ops(uint32_t cmd, struct dev_ops *ops, int minor) 1024 { 1025 devfs_msg_t devfs_msg = devfs_msg_get(); 1026 1027 devfs_msg->mdv_ops.ops = ops; 1028 devfs_msg->mdv_ops.minor = minor; 1029 devfs_msg_send(cmd, devfs_msg); 1030 } 1031 1032 /* 1033 * sends a message with a clone handler argument. 1034 */ 1035 void 1036 devfs_msg_send_chandler(uint32_t cmd, char *name, d_clone_t handler) 1037 { 1038 devfs_msg_t devfs_msg = devfs_msg_get(); 1039 1040 devfs_msg->mdv_chandler.name = name; 1041 devfs_msg->mdv_chandler.nhandler = handler; 1042 devfs_msg_send(cmd, devfs_msg); 1043 } 1044 1045 /* 1046 * sends a message with a device argument. 1047 */ 1048 void 1049 devfs_msg_send_dev(uint32_t cmd, cdev_t dev, uid_t uid, gid_t gid, int perms) 1050 { 1051 devfs_msg_t devfs_msg = devfs_msg_get(); 1052 1053 devfs_msg->mdv_dev.dev = dev; 1054 devfs_msg->mdv_dev.uid = uid; 1055 devfs_msg->mdv_dev.gid = gid; 1056 devfs_msg->mdv_dev.perms = perms; 1057 1058 devfs_msg_send(cmd, devfs_msg); 1059 } 1060 1061 /* 1062 * sends a message with a link argument. 1063 */ 1064 void 1065 devfs_msg_send_link(uint32_t cmd, char *name, char *target, struct mount *mp) 1066 { 1067 devfs_msg_t devfs_msg = devfs_msg_get(); 1068 1069 devfs_msg->mdv_link.name = name; 1070 devfs_msg->mdv_link.target = target; 1071 devfs_msg->mdv_link.mp = mp; 1072 devfs_msg_send(cmd, devfs_msg); 1073 } 1074 1075 /* 1076 * devfs_msg_core is the main devfs thread. It handles all incoming messages 1077 * and calls the relevant worker functions. By using messages it's assured 1078 * that events occur in the correct order. 1079 */ 1080 static void 1081 devfs_msg_core(void *arg) 1082 { 1083 devfs_msg_t msg; 1084 1085 lwkt_initport_thread(&devfs_msg_port, curthread); 1086 1087 lockmgr(&devfs_lock, LK_EXCLUSIVE); 1088 devfs_run = 1; 1089 wakeup(td_core); 1090 lockmgr(&devfs_lock, LK_RELEASE); 1091 1092 get_mplock(); /* mpsafe yet? */ 1093 1094 while (devfs_run) { 1095 msg = (devfs_msg_t)lwkt_waitport(&devfs_msg_port, 0); 1096 devfs_debug(DEVFS_DEBUG_DEBUG, 1097 "devfs_msg_core, new msg: %x\n", 1098 (unsigned int)msg->hdr.u.ms_result); 1099 devfs_msg_exec(msg); 1100 lwkt_replymsg(&msg->hdr, 0); 1101 } 1102 1103 rel_mplock(); 1104 wakeup(td_core); 1105 1106 lwkt_exit(); 1107 } 1108 1109 static void 1110 devfs_msg_exec(devfs_msg_t msg) 1111 { 1112 struct devfs_mnt_data *mnt; 1113 struct devfs_node *node; 1114 cdev_t dev; 1115 1116 /* 1117 * Acquire the devfs lock to ensure safety of all called functions 1118 */ 1119 lockmgr(&devfs_lock, LK_EXCLUSIVE); 1120 1121 switch (msg->hdr.u.ms_result) { 1122 case DEVFS_DEVICE_CREATE: 1123 dev = msg->mdv_dev.dev; 1124 devfs_create_dev_worker(dev, 1125 msg->mdv_dev.uid, 1126 msg->mdv_dev.gid, 1127 msg->mdv_dev.perms); 1128 break; 1129 case DEVFS_DEVICE_DESTROY: 1130 dev = msg->mdv_dev.dev; 1131 devfs_destroy_dev_worker(dev); 1132 break; 1133 case DEVFS_DESTROY_SUBNAMES: 1134 devfs_destroy_subnames_worker(msg->mdv_load); 1135 break; 1136 case DEVFS_DESTROY_DEV_BY_OPS: 1137 devfs_destroy_dev_by_ops_worker(msg->mdv_ops.ops, 1138 msg->mdv_ops.minor); 1139 break; 1140 case DEVFS_CREATE_ALL_DEV: 1141 node = (struct devfs_node *)msg->mdv_load; 1142 devfs_create_all_dev_worker(node); 1143 break; 1144 case DEVFS_MOUNT_ADD: 1145 mnt = msg->mdv_mnt; 1146 TAILQ_INSERT_TAIL(&devfs_mnt_list, mnt, link); 1147 devfs_create_all_dev_worker(mnt->root_node); 1148 break; 1149 case DEVFS_MOUNT_DEL: 1150 mnt = msg->mdv_mnt; 1151 TAILQ_REMOVE(&devfs_mnt_list, mnt, link); 1152 devfs_iterate_topology(mnt->root_node, devfs_reaperp_callback, 1153 NULL); 1154 if (mnt->leak_count) { 1155 devfs_debug(DEVFS_DEBUG_SHOW, 1156 "Leaked %ld devfs_node elements!\n", 1157 mnt->leak_count); 1158 } 1159 break; 1160 case DEVFS_CHANDLER_ADD: 1161 devfs_chandler_add_worker(msg->mdv_chandler.name, 1162 msg->mdv_chandler.nhandler); 1163 break; 1164 case DEVFS_CHANDLER_DEL: 1165 devfs_chandler_del_worker(msg->mdv_chandler.name); 1166 break; 1167 case DEVFS_FIND_DEVICE_BY_NAME: 1168 devfs_find_device_by_name_worker(msg); 1169 break; 1170 case DEVFS_FIND_DEVICE_BY_UDEV: 1171 devfs_find_device_by_udev_worker(msg); 1172 break; 1173 case DEVFS_MAKE_ALIAS: 1174 devfs_make_alias_worker((struct devfs_alias *)msg->mdv_load); 1175 break; 1176 case DEVFS_DESTROY_ALIAS: 1177 devfs_destroy_alias_worker((struct devfs_alias *)msg->mdv_load); 1178 break; 1179 case DEVFS_APPLY_RULES: 1180 devfs_apply_reset_rules_caller(msg->mdv_name, 1); 1181 break; 1182 case DEVFS_RESET_RULES: 1183 devfs_apply_reset_rules_caller(msg->mdv_name, 0); 1184 break; 1185 case DEVFS_SCAN_CALLBACK: 1186 devfs_scan_callback_worker((devfs_scan_t *)msg->mdv_load, 1187 msg->mdv_load2); 1188 break; 1189 case DEVFS_CLR_SUBNAMES_FLAG: 1190 devfs_clr_subnames_flag_worker(msg->mdv_flags.name, 1191 msg->mdv_flags.flag); 1192 break; 1193 case DEVFS_DESTROY_SUBNAMES_WO_FLAG: 1194 devfs_destroy_subnames_without_flag_worker(msg->mdv_flags.name, 1195 msg->mdv_flags.flag); 1196 break; 1197 case DEVFS_INODE_TO_VNODE: 1198 msg->mdv_ino.vp = devfs_iterate_topology( 1199 DEVFS_MNTDATA(msg->mdv_ino.mp)->root_node, 1200 (devfs_iterate_callback_t *)devfs_inode_to_vnode_worker_callback, 1201 &msg->mdv_ino.ino); 1202 break; 1203 case DEVFS_TERMINATE_CORE: 1204 devfs_run = 0; 1205 break; 1206 case DEVFS_SYNC: 1207 break; 1208 default: 1209 devfs_debug(DEVFS_DEBUG_WARNING, 1210 "devfs_msg_core: unknown message " 1211 "received at core\n"); 1212 break; 1213 } 1214 lockmgr(&devfs_lock, LK_RELEASE); 1215 } 1216 1217 /* 1218 * Worker function to insert a new dev into the dev list and initialize its 1219 * permissions. It also calls devfs_propagate_dev which in turn propagates 1220 * the change to all mount points. 1221 * 1222 * The passed dev is already referenced. This reference is eaten by this 1223 * function and represents the dev's linkage into devfs_dev_list. 1224 */ 1225 static int 1226 devfs_create_dev_worker(cdev_t dev, uid_t uid, gid_t gid, int perms) 1227 { 1228 KKASSERT(dev); 1229 1230 dev->si_uid = uid; 1231 dev->si_gid = gid; 1232 dev->si_perms = perms; 1233 1234 devfs_link_dev(dev); 1235 devfs_propagate_dev(dev, 1); 1236 1237 udev_event_attach(dev, NULL, 0); 1238 1239 return 0; 1240 } 1241 1242 /* 1243 * Worker function to delete a dev from the dev list and free the cdev. 1244 * It also calls devfs_propagate_dev which in turn propagates the change 1245 * to all mount points. 1246 */ 1247 static int 1248 devfs_destroy_dev_worker(cdev_t dev) 1249 { 1250 int error; 1251 1252 KKASSERT(dev); 1253 KKASSERT((lockstatus(&devfs_lock, curthread)) == LK_EXCLUSIVE); 1254 1255 error = devfs_unlink_dev(dev); 1256 devfs_propagate_dev(dev, 0); 1257 1258 udev_event_detach(dev, NULL, 0); 1259 1260 if (error == 0) 1261 release_dev(dev); /* link ref */ 1262 release_dev(dev); 1263 release_dev(dev); 1264 1265 return 0; 1266 } 1267 1268 /* 1269 * Worker function to destroy all devices with a certain basename. 1270 * Calls devfs_destroy_dev_worker for the actual destruction. 1271 */ 1272 static int 1273 devfs_destroy_subnames_worker(char *name) 1274 { 1275 cdev_t dev, dev1; 1276 size_t len = strlen(name); 1277 1278 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1279 if ((!strncmp(dev->si_name, name, len)) && 1280 (dev->si_name[len] != '\0')) { 1281 devfs_destroy_dev_worker(dev); 1282 } 1283 } 1284 return 0; 1285 } 1286 1287 static int 1288 devfs_clr_subnames_flag_worker(char *name, uint32_t flag) 1289 { 1290 cdev_t dev, dev1; 1291 size_t len = strlen(name); 1292 1293 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1294 if ((!strncmp(dev->si_name, name, len)) && 1295 (dev->si_name[len] != '\0')) { 1296 dev->si_flags &= ~flag; 1297 } 1298 } 1299 1300 return 0; 1301 } 1302 1303 static int 1304 devfs_destroy_subnames_without_flag_worker(char *name, uint32_t flag) 1305 { 1306 cdev_t dev, dev1; 1307 size_t len = strlen(name); 1308 1309 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1310 if ((!strncmp(dev->si_name, name, len)) && 1311 (dev->si_name[len] != '\0')) { 1312 if (!(dev->si_flags & flag)) { 1313 devfs_destroy_dev_worker(dev); 1314 } 1315 } 1316 } 1317 1318 return 0; 1319 } 1320 1321 /* 1322 * Worker function that creates all device nodes on top of a devfs 1323 * root node. 1324 */ 1325 static int 1326 devfs_create_all_dev_worker(struct devfs_node *root) 1327 { 1328 cdev_t dev; 1329 1330 KKASSERT(root); 1331 1332 TAILQ_FOREACH(dev, &devfs_dev_list, link) { 1333 devfs_create_device_node(root, dev, NULL, NULL); 1334 } 1335 1336 return 0; 1337 } 1338 1339 /* 1340 * Worker function that destroys all devices that match a specific 1341 * dev_ops and/or minor. If minor is less than 0, it is not matched 1342 * against. It also propagates all changes. 1343 */ 1344 static int 1345 devfs_destroy_dev_by_ops_worker(struct dev_ops *ops, int minor) 1346 { 1347 cdev_t dev, dev1; 1348 1349 KKASSERT(ops); 1350 1351 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1352 if (dev->si_ops != ops) 1353 continue; 1354 if ((minor < 0) || (dev->si_uminor == minor)) { 1355 devfs_destroy_dev_worker(dev); 1356 } 1357 } 1358 1359 return 0; 1360 } 1361 1362 /* 1363 * Worker function that registers a new clone handler in devfs. 1364 */ 1365 static int 1366 devfs_chandler_add_worker(const char *name, d_clone_t *nhandler) 1367 { 1368 struct devfs_clone_handler *chandler = NULL; 1369 u_char len = strlen(name); 1370 1371 if (len == 0) 1372 return 1; 1373 1374 TAILQ_FOREACH(chandler, &devfs_chandler_list, link) { 1375 if (chandler->namlen != len) 1376 continue; 1377 1378 if (!memcmp(chandler->name, name, len)) { 1379 /* Clonable basename already exists */ 1380 return 1; 1381 } 1382 } 1383 1384 chandler = kmalloc(sizeof(*chandler), M_DEVFS, M_WAITOK | M_ZERO); 1385 chandler->name = kstrdup(name, M_DEVFS); 1386 chandler->namlen = len; 1387 chandler->nhandler = nhandler; 1388 1389 TAILQ_INSERT_TAIL(&devfs_chandler_list, chandler, link); 1390 return 0; 1391 } 1392 1393 /* 1394 * Worker function that removes a given clone handler from the 1395 * clone handler list. 1396 */ 1397 static int 1398 devfs_chandler_del_worker(const char *name) 1399 { 1400 struct devfs_clone_handler *chandler, *chandler2; 1401 u_char len = strlen(name); 1402 1403 if (len == 0) 1404 return 1; 1405 1406 TAILQ_FOREACH_MUTABLE(chandler, &devfs_chandler_list, link, chandler2) { 1407 if (chandler->namlen != len) 1408 continue; 1409 if (memcmp(chandler->name, name, len)) 1410 continue; 1411 1412 TAILQ_REMOVE(&devfs_chandler_list, chandler, link); 1413 kfree(chandler->name, M_DEVFS); 1414 kfree(chandler, M_DEVFS); 1415 break; 1416 } 1417 1418 return 0; 1419 } 1420 1421 /* 1422 * Worker function that finds a given device name and changes 1423 * the message received accordingly so that when replied to, 1424 * the answer is returned to the caller. 1425 */ 1426 static int 1427 devfs_find_device_by_name_worker(devfs_msg_t devfs_msg) 1428 { 1429 struct devfs_alias *alias; 1430 cdev_t dev; 1431 cdev_t found = NULL; 1432 1433 TAILQ_FOREACH(dev, &devfs_dev_list, link) { 1434 if (strcmp(devfs_msg->mdv_name, dev->si_name) == 0) { 1435 found = dev; 1436 break; 1437 } 1438 } 1439 if (found == NULL) { 1440 TAILQ_FOREACH(alias, &devfs_alias_list, link) { 1441 if (strcmp(devfs_msg->mdv_name, alias->name) == 0) { 1442 found = alias->dev_target; 1443 break; 1444 } 1445 } 1446 } 1447 devfs_msg->mdv_cdev = found; 1448 1449 return 0; 1450 } 1451 1452 /* 1453 * Worker function that finds a given device udev and changes 1454 * the message received accordingly so that when replied to, 1455 * the answer is returned to the caller. 1456 */ 1457 static int 1458 devfs_find_device_by_udev_worker(devfs_msg_t devfs_msg) 1459 { 1460 cdev_t dev, dev1; 1461 cdev_t found = NULL; 1462 1463 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1464 if (((udev_t)dev->si_inode) == devfs_msg->mdv_udev) { 1465 found = dev; 1466 break; 1467 } 1468 } 1469 devfs_msg->mdv_cdev = found; 1470 1471 return 0; 1472 } 1473 1474 /* 1475 * Worker function that inserts a given alias into the 1476 * alias list, and propagates the alias to all mount 1477 * points. 1478 */ 1479 static int 1480 devfs_make_alias_worker(struct devfs_alias *alias) 1481 { 1482 struct devfs_alias *alias2; 1483 size_t len = strlen(alias->name); 1484 int found = 0; 1485 1486 TAILQ_FOREACH(alias2, &devfs_alias_list, link) { 1487 if (len != alias2->namlen) 1488 continue; 1489 1490 if (!memcmp(alias->name, alias2->name, len)) { 1491 found = 1; 1492 break; 1493 } 1494 } 1495 1496 if (!found) { 1497 /* 1498 * The alias doesn't exist yet, so we add it to the alias list 1499 */ 1500 TAILQ_INSERT_TAIL(&devfs_alias_list, alias, link); 1501 devfs_alias_propagate(alias, 0); 1502 udev_event_attach(alias->dev_target, alias->name, 1); 1503 } else { 1504 devfs_debug(DEVFS_DEBUG_WARNING, 1505 "Warning: duplicate devfs_make_alias for %s\n", 1506 alias->name); 1507 kfree(alias->name, M_DEVFS); 1508 kfree(alias, M_DEVFS); 1509 } 1510 1511 return 0; 1512 } 1513 1514 /* 1515 * Worker function that delete a given alias from the 1516 * alias list, and propagates the removal to all mount 1517 * points. 1518 */ 1519 static int 1520 devfs_destroy_alias_worker(struct devfs_alias *alias) 1521 { 1522 struct devfs_alias *alias2; 1523 int found = 0; 1524 1525 TAILQ_FOREACH(alias2, &devfs_alias_list, link) { 1526 if (alias->dev_target != alias2->dev_target) 1527 continue; 1528 1529 if (devfs_WildCmp(alias->name, alias2->name) == 0) { 1530 found = 1; 1531 break; 1532 } 1533 } 1534 1535 if (!found) { 1536 devfs_debug(DEVFS_DEBUG_WARNING, 1537 "Warning: devfs_destroy_alias for inexistant alias: %s\n", 1538 alias->name); 1539 kfree(alias->name, M_DEVFS); 1540 kfree(alias, M_DEVFS); 1541 } else { 1542 /* 1543 * The alias exists, so we delete it from the alias list 1544 */ 1545 TAILQ_REMOVE(&devfs_alias_list, alias2, link); 1546 devfs_alias_propagate(alias2, 1); 1547 udev_event_detach(alias2->dev_target, alias2->name, 1); 1548 kfree(alias->name, M_DEVFS); 1549 kfree(alias, M_DEVFS); 1550 kfree(alias2->name, M_DEVFS); 1551 kfree(alias2, M_DEVFS); 1552 } 1553 1554 return 0; 1555 } 1556 1557 /* 1558 * Function that removes and frees all aliases. 1559 */ 1560 static int 1561 devfs_alias_reap(void) 1562 { 1563 struct devfs_alias *alias, *alias2; 1564 1565 TAILQ_FOREACH_MUTABLE(alias, &devfs_alias_list, link, alias2) { 1566 TAILQ_REMOVE(&devfs_alias_list, alias, link); 1567 kfree(alias->name, M_DEVFS); 1568 kfree(alias, M_DEVFS); 1569 } 1570 return 0; 1571 } 1572 1573 /* 1574 * Function that removes an alias matching a specific cdev and frees 1575 * it accordingly. 1576 */ 1577 static int 1578 devfs_alias_remove(cdev_t dev) 1579 { 1580 struct devfs_alias *alias, *alias2; 1581 1582 TAILQ_FOREACH_MUTABLE(alias, &devfs_alias_list, link, alias2) { 1583 if (alias->dev_target == dev) { 1584 TAILQ_REMOVE(&devfs_alias_list, alias, link); 1585 udev_event_detach(alias->dev_target, alias->name, 1); 1586 kfree(alias->name, M_DEVFS); 1587 kfree(alias, M_DEVFS); 1588 } 1589 } 1590 return 0; 1591 } 1592 1593 /* 1594 * This function propagates an alias addition or removal to 1595 * all mount points. 1596 */ 1597 static int 1598 devfs_alias_propagate(struct devfs_alias *alias, int remove) 1599 { 1600 struct devfs_mnt_data *mnt; 1601 1602 TAILQ_FOREACH(mnt, &devfs_mnt_list, link) { 1603 if (remove) { 1604 devfs_destroy_node(mnt->root_node, alias->name); 1605 } else { 1606 devfs_alias_apply(mnt->root_node, alias); 1607 } 1608 } 1609 return 0; 1610 } 1611 1612 /* 1613 * This function is a recursive function iterating through 1614 * all device nodes in the topology and, if applicable, 1615 * creating the relevant alias for a device node. 1616 */ 1617 static int 1618 devfs_alias_apply(struct devfs_node *node, struct devfs_alias *alias) 1619 { 1620 struct devfs_node *node1, *node2; 1621 1622 KKASSERT(alias != NULL); 1623 1624 if ((node->node_type == Proot) || (node->node_type == Pdir)) { 1625 if (node->nchildren > 2) { 1626 TAILQ_FOREACH_MUTABLE(node1, DEVFS_DENODE_HEAD(node), link, node2) { 1627 devfs_alias_apply(node1, alias); 1628 } 1629 } 1630 } else { 1631 if (node->d_dev == alias->dev_target) 1632 devfs_alias_create(alias->name, node, 0); 1633 } 1634 return 0; 1635 } 1636 1637 /* 1638 * This function checks if any alias possibly is applicable 1639 * to the given node. If so, the alias is created. 1640 */ 1641 static int 1642 devfs_alias_check_create(struct devfs_node *node) 1643 { 1644 struct devfs_alias *alias; 1645 1646 TAILQ_FOREACH(alias, &devfs_alias_list, link) { 1647 if (node->d_dev == alias->dev_target) 1648 devfs_alias_create(alias->name, node, 0); 1649 } 1650 return 0; 1651 } 1652 1653 /* 1654 * This function creates an alias with a given name 1655 * linking to a given devfs node. It also increments 1656 * the link count on the target node. 1657 */ 1658 int 1659 devfs_alias_create(char *name_orig, struct devfs_node *target, int rule_based) 1660 { 1661 struct mount *mp = target->mp; 1662 struct devfs_node *parent = DEVFS_MNTDATA(mp)->root_node; 1663 struct devfs_node *linknode; 1664 char *create_path = NULL; 1665 char *name; 1666 char *name_buf; 1667 int result = 0; 1668 1669 KKASSERT((lockstatus(&devfs_lock, curthread)) == LK_EXCLUSIVE); 1670 1671 name_buf = kmalloc(PATH_MAX, M_TEMP, M_WAITOK); 1672 devfs_resolve_name_path(name_orig, name_buf, &create_path, &name); 1673 1674 if (create_path) 1675 parent = devfs_resolve_or_create_path(parent, create_path, 1); 1676 1677 1678 if (devfs_find_device_node_by_name(parent, name)) { 1679 devfs_debug(DEVFS_DEBUG_WARNING, 1680 "Node already exists: %s " 1681 "(devfs_make_alias_worker)!\n", 1682 name); 1683 result = 1; 1684 goto done; 1685 } 1686 1687 linknode = devfs_allocp(Plink, name, parent, mp, NULL); 1688 if (linknode == NULL) { 1689 result = 1; 1690 goto done; 1691 } 1692 1693 linknode->link_target = target; 1694 target->nlinks++; 1695 1696 if (rule_based) 1697 linknode->flags |= DEVFS_RULE_CREATED; 1698 1699 done: 1700 kfree(name_buf, M_TEMP); 1701 return (result); 1702 } 1703 1704 /* 1705 * This function is called by the core and handles mount point 1706 * strings. It either calls the relevant worker (devfs_apply_ 1707 * reset_rules_worker) on all mountpoints or only a specific 1708 * one. 1709 */ 1710 static int 1711 devfs_apply_reset_rules_caller(char *mountto, int apply) 1712 { 1713 struct devfs_mnt_data *mnt; 1714 1715 if (mountto[0] == '*') { 1716 TAILQ_FOREACH(mnt, &devfs_mnt_list, link) { 1717 devfs_iterate_topology(mnt->root_node, 1718 (apply)?(devfs_rule_check_apply):(devfs_rule_reset_node), 1719 NULL); 1720 } 1721 } else { 1722 TAILQ_FOREACH(mnt, &devfs_mnt_list, link) { 1723 if (!strcmp(mnt->mp->mnt_stat.f_mntonname, mountto)) { 1724 devfs_iterate_topology(mnt->root_node, 1725 (apply)?(devfs_rule_check_apply):(devfs_rule_reset_node), 1726 NULL); 1727 break; 1728 } 1729 } 1730 } 1731 1732 kfree(mountto, M_DEVFS); 1733 return 0; 1734 } 1735 1736 /* 1737 * This function calls a given callback function for 1738 * every dev node in the devfs dev list. 1739 */ 1740 static int 1741 devfs_scan_callback_worker(devfs_scan_t *callback, void *arg) 1742 { 1743 cdev_t dev, dev1; 1744 1745 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1746 callback(dev, arg); 1747 } 1748 1749 return 0; 1750 } 1751 1752 /* 1753 * This function tries to resolve a given directory, or if not 1754 * found and creation requested, creates the given directory. 1755 */ 1756 static struct devfs_node * 1757 devfs_resolve_or_create_dir(struct devfs_node *parent, char *dir_name, 1758 size_t name_len, int create) 1759 { 1760 struct devfs_node *node, *found = NULL; 1761 1762 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(parent), link) { 1763 if (name_len != node->d_dir.d_namlen) 1764 continue; 1765 1766 if (!memcmp(dir_name, node->d_dir.d_name, name_len)) { 1767 found = node; 1768 break; 1769 } 1770 } 1771 1772 if ((found == NULL) && (create)) { 1773 found = devfs_allocp(Pdir, dir_name, parent, parent->mp, NULL); 1774 } 1775 1776 return found; 1777 } 1778 1779 /* 1780 * This function tries to resolve a complete path. If creation is requested, 1781 * if a given part of the path cannot be resolved (because it doesn't exist), 1782 * it is created. 1783 */ 1784 struct devfs_node * 1785 devfs_resolve_or_create_path(struct devfs_node *parent, char *path, int create) 1786 { 1787 struct devfs_node *node = parent; 1788 char *buf; 1789 size_t idx = 0; 1790 1791 if (path == NULL) 1792 return parent; 1793 1794 buf = kmalloc(PATH_MAX, M_TEMP, M_WAITOK); 1795 1796 while (*path && idx < PATH_MAX - 1) { 1797 if (*path != '/') { 1798 buf[idx++] = *path; 1799 } else { 1800 buf[idx] = '\0'; 1801 node = devfs_resolve_or_create_dir(node, buf, idx, create); 1802 if (node == NULL) { 1803 kfree(buf, M_TEMP); 1804 return NULL; 1805 } 1806 idx = 0; 1807 } 1808 ++path; 1809 } 1810 buf[idx] = '\0'; 1811 node = devfs_resolve_or_create_dir(node, buf, idx, create); 1812 kfree (buf, M_TEMP); 1813 return (node); 1814 } 1815 1816 /* 1817 * Takes a full path and strips it into a directory path and a name. 1818 * For a/b/c/foo, it returns foo in namep and a/b/c in pathp. It 1819 * requires a working buffer with enough size to keep the whole 1820 * fullpath. 1821 */ 1822 int 1823 devfs_resolve_name_path(char *fullpath, char *buf, char **pathp, char **namep) 1824 { 1825 char *name = NULL; 1826 char *path = NULL; 1827 size_t len = strlen(fullpath) + 1; 1828 int i; 1829 1830 KKASSERT((fullpath != NULL) && (buf != NULL)); 1831 KKASSERT((pathp != NULL) && (namep != NULL)); 1832 1833 memcpy(buf, fullpath, len); 1834 1835 for (i = len-1; i>= 0; i--) { 1836 if (buf[i] == '/') { 1837 buf[i] = '\0'; 1838 name = &(buf[i+1]); 1839 path = buf; 1840 break; 1841 } 1842 } 1843 1844 *pathp = path; 1845 1846 if (name) { 1847 *namep = name; 1848 } else { 1849 *namep = buf; 1850 } 1851 1852 return 0; 1853 } 1854 1855 /* 1856 * This function creates a new devfs node for a given device. It can 1857 * handle a complete path as device name, and accordingly creates 1858 * the path and the final device node. 1859 * 1860 * The reference count on the passed dev remains unchanged. 1861 */ 1862 struct devfs_node * 1863 devfs_create_device_node(struct devfs_node *root, cdev_t dev, 1864 char *dev_name, char *path_fmt, ...) 1865 { 1866 struct devfs_node *parent, *node = NULL; 1867 char *path = NULL; 1868 char *name; 1869 char *name_buf; 1870 __va_list ap; 1871 int i, found; 1872 char *create_path = NULL; 1873 char *names = "pqrsPQRS"; 1874 1875 name_buf = kmalloc(PATH_MAX, M_TEMP, M_WAITOK); 1876 1877 if (path_fmt != NULL) { 1878 __va_start(ap, path_fmt); 1879 kvasnrprintf(&path, PATH_MAX, 10, path_fmt, ap); 1880 __va_end(ap); 1881 } 1882 1883 parent = devfs_resolve_or_create_path(root, path, 1); 1884 KKASSERT(parent); 1885 1886 devfs_resolve_name_path( 1887 ((dev_name == NULL) && (dev))?(dev->si_name):(dev_name), 1888 name_buf, &create_path, &name); 1889 1890 if (create_path) 1891 parent = devfs_resolve_or_create_path(parent, create_path, 1); 1892 1893 1894 if (devfs_find_device_node_by_name(parent, name)) { 1895 devfs_debug(DEVFS_DEBUG_WARNING, "devfs_create_device_node: " 1896 "DEVICE %s ALREADY EXISTS!!! Ignoring creation request.\n", name); 1897 goto out; 1898 } 1899 1900 node = devfs_allocp(Pdev, name, parent, parent->mp, dev); 1901 nanotime(&parent->mtime); 1902 1903 /* 1904 * Ugly unix98 pty magic, to hide pty master (ptm) devices and their 1905 * directory 1906 */ 1907 if ((dev) && (strlen(dev->si_name) >= 4) && 1908 (!memcmp(dev->si_name, "ptm/", 4))) { 1909 node->parent->flags |= DEVFS_HIDDEN; 1910 node->flags |= DEVFS_HIDDEN; 1911 } 1912 1913 /* 1914 * Ugly pty magic, to tag pty devices as such and hide them if needed. 1915 */ 1916 if ((strlen(name) >= 3) && (!memcmp(name, "pty", 3))) 1917 node->flags |= (DEVFS_PTY | DEVFS_INVISIBLE); 1918 1919 if ((strlen(name) >= 3) && (!memcmp(name, "tty", 3))) { 1920 found = 0; 1921 for (i = 0; i < strlen(names); i++) { 1922 if (name[3] == names[i]) { 1923 found = 1; 1924 break; 1925 } 1926 } 1927 if (found) 1928 node->flags |= (DEVFS_PTY | DEVFS_INVISIBLE); 1929 } 1930 1931 out: 1932 kfree(name_buf, M_TEMP); 1933 kvasfree(&path); 1934 return node; 1935 } 1936 1937 /* 1938 * This function finds a given device node in the topology with a given 1939 * cdev. 1940 */ 1941 void * 1942 devfs_find_device_node_callback(struct devfs_node *node, cdev_t target) 1943 { 1944 if ((node->node_type == Pdev) && (node->d_dev == target)) { 1945 return node; 1946 } 1947 1948 return NULL; 1949 } 1950 1951 /* 1952 * This function finds a device node in the given parent directory by its 1953 * name and returns it. 1954 */ 1955 struct devfs_node * 1956 devfs_find_device_node_by_name(struct devfs_node *parent, char *target) 1957 { 1958 struct devfs_node *node, *found = NULL; 1959 size_t len = strlen(target); 1960 1961 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(parent), link) { 1962 if (len != node->d_dir.d_namlen) 1963 continue; 1964 1965 if (!memcmp(node->d_dir.d_name, target, len)) { 1966 found = node; 1967 break; 1968 } 1969 } 1970 1971 return found; 1972 } 1973 1974 static void * 1975 devfs_inode_to_vnode_worker_callback(struct devfs_node *node, ino_t *inop) 1976 { 1977 struct vnode *vp = NULL; 1978 ino_t target = *inop; 1979 1980 if (node->d_dir.d_ino == target) { 1981 if (node->v_node) { 1982 vp = node->v_node; 1983 vget(vp, LK_EXCLUSIVE | LK_RETRY); 1984 vn_unlock(vp); 1985 } else { 1986 devfs_allocv(&vp, node); 1987 vn_unlock(vp); 1988 } 1989 } 1990 1991 return vp; 1992 } 1993 1994 /* 1995 * This function takes a cdev and removes its devfs node in the 1996 * given topology. The cdev remains intact. 1997 */ 1998 int 1999 devfs_destroy_device_node(struct devfs_node *root, cdev_t target) 2000 { 2001 KKASSERT(target != NULL); 2002 return devfs_destroy_node(root, target->si_name); 2003 } 2004 2005 /* 2006 * This function takes a path to a devfs node, resolves it and 2007 * removes the devfs node from the given topology. 2008 */ 2009 int 2010 devfs_destroy_node(struct devfs_node *root, char *target) 2011 { 2012 struct devfs_node *node, *parent; 2013 char *name; 2014 char *name_buf; 2015 char *create_path = NULL; 2016 2017 KKASSERT(target); 2018 2019 name_buf = kmalloc(PATH_MAX, M_TEMP, M_WAITOK); 2020 ksnprintf(name_buf, PATH_MAX, "%s", target); 2021 2022 devfs_resolve_name_path(target, name_buf, &create_path, &name); 2023 2024 if (create_path) 2025 parent = devfs_resolve_or_create_path(root, create_path, 0); 2026 else 2027 parent = root; 2028 2029 if (parent == NULL) { 2030 kfree(name_buf, M_TEMP); 2031 return 1; 2032 } 2033 2034 node = devfs_find_device_node_by_name(parent, name); 2035 2036 if (node) { 2037 nanotime(&node->parent->mtime); 2038 devfs_gc(node); 2039 } 2040 2041 kfree(name_buf, M_TEMP); 2042 2043 return 0; 2044 } 2045 2046 /* 2047 * Just set perms and ownership for given node. 2048 */ 2049 int 2050 devfs_set_perms(struct devfs_node *node, uid_t uid, gid_t gid, 2051 u_short mode, u_long flags) 2052 { 2053 node->mode = mode; 2054 node->uid = uid; 2055 node->gid = gid; 2056 2057 return 0; 2058 } 2059 2060 /* 2061 * Propagates a device attach/detach to all mount 2062 * points. Also takes care of automatic alias removal 2063 * for a deleted cdev. 2064 */ 2065 static int 2066 devfs_propagate_dev(cdev_t dev, int attach) 2067 { 2068 struct devfs_mnt_data *mnt; 2069 2070 TAILQ_FOREACH(mnt, &devfs_mnt_list, link) { 2071 if (attach) { 2072 /* Device is being attached */ 2073 devfs_create_device_node(mnt->root_node, dev, 2074 NULL, NULL ); 2075 } else { 2076 /* Device is being detached */ 2077 devfs_alias_remove(dev); 2078 devfs_destroy_device_node(mnt->root_node, dev); 2079 } 2080 } 2081 return 0; 2082 } 2083 2084 /* 2085 * devfs_clone either returns a basename from a complete name by 2086 * returning the length of the name without trailing digits, or, 2087 * if clone != 0, calls the device's clone handler to get a new 2088 * device, which in turn is returned in devp. 2089 */ 2090 cdev_t 2091 devfs_clone(cdev_t dev, const char *name, size_t len, int mode, 2092 struct ucred *cred) 2093 { 2094 int error; 2095 struct devfs_clone_handler *chandler; 2096 struct dev_clone_args ap; 2097 2098 TAILQ_FOREACH(chandler, &devfs_chandler_list, link) { 2099 if (chandler->namlen != len) 2100 continue; 2101 if ((!memcmp(chandler->name, name, len)) && (chandler->nhandler)) { 2102 lockmgr(&devfs_lock, LK_RELEASE); 2103 devfs_config(); 2104 lockmgr(&devfs_lock, LK_EXCLUSIVE); 2105 2106 ap.a_head.a_dev = dev; 2107 ap.a_dev = NULL; 2108 ap.a_name = name; 2109 ap.a_namelen = len; 2110 ap.a_mode = mode; 2111 ap.a_cred = cred; 2112 error = (chandler->nhandler)(&ap); 2113 if (error) 2114 continue; 2115 2116 return ap.a_dev; 2117 } 2118 } 2119 2120 return NULL; 2121 } 2122 2123 2124 /* 2125 * Registers a new orphan in the orphan list. 2126 */ 2127 void 2128 devfs_tracer_add_orphan(struct devfs_node *node) 2129 { 2130 struct devfs_orphan *orphan; 2131 2132 KKASSERT(node); 2133 orphan = kmalloc(sizeof(struct devfs_orphan), M_DEVFS, M_WAITOK); 2134 orphan->node = node; 2135 2136 KKASSERT((node->flags & DEVFS_ORPHANED) == 0); 2137 node->flags |= DEVFS_ORPHANED; 2138 TAILQ_INSERT_TAIL(DEVFS_ORPHANLIST(node->mp), orphan, link); 2139 } 2140 2141 /* 2142 * Removes an orphan from the orphan list. 2143 */ 2144 void 2145 devfs_tracer_del_orphan(struct devfs_node *node) 2146 { 2147 struct devfs_orphan *orphan; 2148 2149 KKASSERT(node); 2150 2151 TAILQ_FOREACH(orphan, DEVFS_ORPHANLIST(node->mp), link) { 2152 if (orphan->node == node) { 2153 node->flags &= ~DEVFS_ORPHANED; 2154 TAILQ_REMOVE(DEVFS_ORPHANLIST(node->mp), orphan, link); 2155 kfree(orphan, M_DEVFS); 2156 break; 2157 } 2158 } 2159 } 2160 2161 /* 2162 * Counts the orphans in the orphan list, and if cleanup 2163 * is specified, also frees the orphan and removes it from 2164 * the list. 2165 */ 2166 size_t 2167 devfs_tracer_orphan_count(struct mount *mp, int cleanup) 2168 { 2169 struct devfs_orphan *orphan, *orphan2; 2170 size_t count = 0; 2171 2172 TAILQ_FOREACH_MUTABLE(orphan, DEVFS_ORPHANLIST(mp), link, orphan2) { 2173 count++; 2174 /* 2175 * If we are instructed to clean up, we do so. 2176 */ 2177 if (cleanup) { 2178 TAILQ_REMOVE(DEVFS_ORPHANLIST(mp), orphan, link); 2179 orphan->node->flags &= ~DEVFS_ORPHANED; 2180 devfs_freep(orphan->node); 2181 kfree(orphan, M_DEVFS); 2182 } 2183 } 2184 2185 return count; 2186 } 2187 2188 /* 2189 * Fetch an ino_t from the global d_ino by increasing it 2190 * while spinlocked. 2191 */ 2192 static ino_t 2193 devfs_fetch_ino(void) 2194 { 2195 ino_t ret; 2196 2197 spin_lock(&ino_lock); 2198 ret = d_ino++; 2199 spin_unlock(&ino_lock); 2200 2201 return ret; 2202 } 2203 2204 /* 2205 * Allocates a new cdev and initializes it's most basic 2206 * fields. 2207 */ 2208 cdev_t 2209 devfs_new_cdev(struct dev_ops *ops, int minor, struct dev_ops *bops) 2210 { 2211 cdev_t dev = sysref_alloc(&cdev_sysref_class); 2212 2213 sysref_activate(&dev->si_sysref); 2214 reference_dev(dev); 2215 bzero(dev, offsetof(struct cdev, si_sysref)); 2216 2217 dev->si_uid = 0; 2218 dev->si_gid = 0; 2219 dev->si_perms = 0; 2220 dev->si_drv1 = NULL; 2221 dev->si_drv2 = NULL; 2222 dev->si_lastread = 0; /* time_second */ 2223 dev->si_lastwrite = 0; /* time_second */ 2224 2225 dev->si_dict = NULL; 2226 dev->si_ops = ops; 2227 dev->si_flags = 0; 2228 dev->si_umajor = 0; 2229 dev->si_uminor = minor; 2230 dev->si_bops = bops; 2231 2232 /* 2233 * Since the disk subsystem is in the way, we need to 2234 * propagate the D_CANFREE from bops (and ops) to 2235 * si_flags. 2236 */ 2237 if (bops && (bops->head.flags & D_CANFREE)) { 2238 dev->si_flags |= SI_CANFREE; 2239 } else if (ops->head.flags & D_CANFREE) { 2240 dev->si_flags |= SI_CANFREE; 2241 } 2242 2243 /* If there is a backing device, we reference its ops */ 2244 dev->si_inode = makeudev( 2245 devfs_reference_ops((bops)?(bops):(ops)), 2246 minor ); 2247 2248 return dev; 2249 } 2250 2251 static void 2252 devfs_cdev_terminate(cdev_t dev) 2253 { 2254 int locked = 0; 2255 2256 /* Check if it is locked already. if not, we acquire the devfs lock */ 2257 if (!(lockstatus(&devfs_lock, curthread)) == LK_EXCLUSIVE) { 2258 lockmgr(&devfs_lock, LK_EXCLUSIVE); 2259 locked = 1; 2260 } 2261 2262 /* 2263 * Make sure the node isn't linked anymore. Otherwise we've screwed 2264 * up somewhere, since normal devs are unlinked on the call to 2265 * destroy_dev and only-cdevs that have not been used for cloning 2266 * are not linked in the first place. only-cdevs used for cloning 2267 * will be linked in, too, and should only be destroyed via 2268 * destroy_dev, not destroy_only_dev, so we catch that problem, too. 2269 */ 2270 KKASSERT((dev->si_flags & SI_DEVFS_LINKED) == 0); 2271 2272 /* If we acquired the lock, we also get rid of it */ 2273 if (locked) 2274 lockmgr(&devfs_lock, LK_RELEASE); 2275 2276 /* If there is a backing device, we release the backing device's ops */ 2277 devfs_release_ops((dev->si_bops)?(dev->si_bops):(dev->si_ops)); 2278 2279 /* Finally destroy the device */ 2280 sysref_put(&dev->si_sysref); 2281 } 2282 2283 /* 2284 * Dummies for now (individual locks for MPSAFE) 2285 */ 2286 static void 2287 devfs_cdev_lock(cdev_t dev) 2288 { 2289 } 2290 2291 static void 2292 devfs_cdev_unlock(cdev_t dev) 2293 { 2294 } 2295 2296 static int 2297 devfs_detached_filter_eof(struct knote *kn, long hint) 2298 { 2299 kn->kn_flags |= EV_EOF; 2300 return (1); 2301 } 2302 2303 static void 2304 devfs_detached_filter_detach(struct knote *kn) 2305 { 2306 cdev_t dev = (cdev_t)kn->kn_hook; 2307 2308 knote_remove(&dev->si_kqinfo.ki_note, kn); 2309 } 2310 2311 static struct filterops devfs_detached_filterops = 2312 { FILTEROP_ISFD, NULL, 2313 devfs_detached_filter_detach, 2314 devfs_detached_filter_eof }; 2315 2316 /* 2317 * Delegates knote filter handling responsibility to devfs 2318 * 2319 * Any device that implements kqfilter event handling and could be detached 2320 * or shut down out from under the kevent subsystem must allow devfs to 2321 * assume responsibility for any knotes it may hold. 2322 */ 2323 void 2324 devfs_assume_knotes(cdev_t dev, struct kqinfo *kqi) 2325 { 2326 /* 2327 * Let kern/kern_event.c do the heavy lifting. 2328 */ 2329 knote_assume_knotes(kqi, &dev->si_kqinfo, 2330 &devfs_detached_filterops, (void *)dev); 2331 2332 /* 2333 * These should probably be activated individually, but doing so 2334 * would require refactoring kq's public in-kernel interface. 2335 */ 2336 KNOTE(&dev->si_kqinfo.ki_note, 0); 2337 } 2338 2339 /* 2340 * Links a given cdev into the dev list. 2341 */ 2342 int 2343 devfs_link_dev(cdev_t dev) 2344 { 2345 KKASSERT((dev->si_flags & SI_DEVFS_LINKED) == 0); 2346 dev->si_flags |= SI_DEVFS_LINKED; 2347 TAILQ_INSERT_TAIL(&devfs_dev_list, dev, link); 2348 2349 return 0; 2350 } 2351 2352 /* 2353 * Removes a given cdev from the dev list. The caller is responsible for 2354 * releasing the reference on the device associated with the linkage. 2355 * 2356 * Returns EALREADY if the dev has already been unlinked. 2357 */ 2358 static int 2359 devfs_unlink_dev(cdev_t dev) 2360 { 2361 if ((dev->si_flags & SI_DEVFS_LINKED)) { 2362 TAILQ_REMOVE(&devfs_dev_list, dev, link); 2363 dev->si_flags &= ~SI_DEVFS_LINKED; 2364 return (0); 2365 } 2366 return (EALREADY); 2367 } 2368 2369 int 2370 devfs_node_is_accessible(struct devfs_node *node) 2371 { 2372 if ((node) && (!(node->flags & DEVFS_HIDDEN))) 2373 return 1; 2374 else 2375 return 0; 2376 } 2377 2378 int 2379 devfs_reference_ops(struct dev_ops *ops) 2380 { 2381 int unit; 2382 struct devfs_dev_ops *found = NULL; 2383 struct devfs_dev_ops *devops; 2384 2385 TAILQ_FOREACH(devops, &devfs_dev_ops_list, link) { 2386 if (devops->ops == ops) { 2387 found = devops; 2388 break; 2389 } 2390 } 2391 2392 if (!found) { 2393 found = kmalloc(sizeof(struct devfs_dev_ops), M_DEVFS, M_WAITOK); 2394 found->ops = ops; 2395 found->ref_count = 0; 2396 TAILQ_INSERT_TAIL(&devfs_dev_ops_list, found, link); 2397 } 2398 2399 KKASSERT(found); 2400 2401 if (found->ref_count == 0) { 2402 found->id = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(ops_id), 255); 2403 if (found->id == -1) { 2404 /* Ran out of unique ids */ 2405 devfs_debug(DEVFS_DEBUG_WARNING, 2406 "devfs_reference_ops: WARNING: ran out of unique ids\n"); 2407 } 2408 } 2409 unit = found->id; 2410 ++found->ref_count; 2411 2412 return unit; 2413 } 2414 2415 void 2416 devfs_release_ops(struct dev_ops *ops) 2417 { 2418 struct devfs_dev_ops *found = NULL; 2419 struct devfs_dev_ops *devops; 2420 2421 TAILQ_FOREACH(devops, &devfs_dev_ops_list, link) { 2422 if (devops->ops == ops) { 2423 found = devops; 2424 break; 2425 } 2426 } 2427 2428 KKASSERT(found); 2429 2430 --found->ref_count; 2431 2432 if (found->ref_count == 0) { 2433 TAILQ_REMOVE(&devfs_dev_ops_list, found, link); 2434 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(ops_id), found->id); 2435 kfree(found, M_DEVFS); 2436 } 2437 } 2438 2439 /* 2440 * Wait for asynchronous messages to complete in the devfs helper 2441 * thread, then return. Do nothing if the helper thread is dead 2442 * or we are being indirectly called from the helper thread itself. 2443 */ 2444 void 2445 devfs_config(void) 2446 { 2447 devfs_msg_t msg; 2448 2449 if (devfs_run && curthread != td_core) { 2450 msg = devfs_msg_get(); 2451 msg = devfs_msg_send_sync(DEVFS_SYNC, msg); 2452 devfs_msg_put(msg); 2453 } 2454 } 2455 2456 /* 2457 * Called on init of devfs; creates the objcaches and 2458 * spawns off the devfs core thread. Also initializes 2459 * locks. 2460 */ 2461 static void 2462 devfs_init(void) 2463 { 2464 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_init() called\n"); 2465 /* Create objcaches for nodes, msgs and devs */ 2466 devfs_node_cache = objcache_create("devfs-node-cache", 0, 0, 2467 NULL, NULL, NULL, 2468 objcache_malloc_alloc, 2469 objcache_malloc_free, 2470 &devfs_node_malloc_args ); 2471 2472 devfs_msg_cache = objcache_create("devfs-msg-cache", 0, 0, 2473 NULL, NULL, NULL, 2474 objcache_malloc_alloc, 2475 objcache_malloc_free, 2476 &devfs_msg_malloc_args ); 2477 2478 devfs_dev_cache = objcache_create("devfs-dev-cache", 0, 0, 2479 NULL, NULL, NULL, 2480 objcache_malloc_alloc, 2481 objcache_malloc_free, 2482 &devfs_dev_malloc_args ); 2483 2484 devfs_clone_bitmap_init(&DEVFS_CLONE_BITMAP(ops_id)); 2485 2486 /* Initialize the reply-only port which acts as a message drain */ 2487 lwkt_initport_replyonly(&devfs_dispose_port, devfs_msg_autofree_reply); 2488 2489 /* Initialize *THE* devfs lock */ 2490 lockinit(&devfs_lock, "devfs_core lock", 0, 0); 2491 2492 lockmgr(&devfs_lock, LK_EXCLUSIVE); 2493 lwkt_create(devfs_msg_core, /*args*/NULL, &td_core, NULL, 2494 0, 0, "devfs_msg_core"); 2495 while (devfs_run == 0) 2496 lksleep(td_core, &devfs_lock, 0, "devfsc", 0); 2497 lockmgr(&devfs_lock, LK_RELEASE); 2498 2499 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_init finished\n"); 2500 } 2501 2502 /* 2503 * Called on unload of devfs; takes care of destroying the core 2504 * and the objcaches. Also removes aliases that are no longer needed. 2505 */ 2506 static void 2507 devfs_uninit(void) 2508 { 2509 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_uninit() called\n"); 2510 2511 devfs_msg_send(DEVFS_TERMINATE_CORE, NULL); 2512 while (devfs_run) 2513 tsleep(td_core, 0, "devfsc", hz*10); 2514 tsleep(td_core, 0, "devfsc", hz); 2515 2516 devfs_clone_bitmap_uninit(&DEVFS_CLONE_BITMAP(ops_id)); 2517 2518 /* Destroy the objcaches */ 2519 objcache_destroy(devfs_msg_cache); 2520 objcache_destroy(devfs_node_cache); 2521 objcache_destroy(devfs_dev_cache); 2522 2523 devfs_alias_reap(); 2524 } 2525 2526 /* 2527 * This is a sysctl handler to assist userland devname(3) to 2528 * find the device name for a given udev. 2529 */ 2530 static int 2531 devfs_sysctl_devname_helper(SYSCTL_HANDLER_ARGS) 2532 { 2533 udev_t udev; 2534 cdev_t found; 2535 int error; 2536 2537 2538 if ((error = SYSCTL_IN(req, &udev, sizeof(udev_t)))) 2539 return (error); 2540 2541 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs sysctl, received udev: %d\n", udev); 2542 2543 if (udev == NOUDEV) 2544 return(EINVAL); 2545 2546 if ((found = devfs_find_device_by_udev(udev)) == NULL) 2547 return(ENOENT); 2548 2549 return(SYSCTL_OUT(req, found->si_name, strlen(found->si_name) + 1)); 2550 } 2551 2552 2553 SYSCTL_PROC(_kern, OID_AUTO, devname, CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY, 2554 NULL, 0, devfs_sysctl_devname_helper, "", "helper for devname(3)"); 2555 2556 SYSCTL_NODE(_vfs, OID_AUTO, devfs, CTLFLAG_RW, 0, "devfs"); 2557 TUNABLE_INT("vfs.devfs.debug", &devfs_debug_enable); 2558 SYSCTL_INT(_vfs_devfs, OID_AUTO, debug, CTLFLAG_RW, &devfs_debug_enable, 2559 0, "Enable DevFS debugging"); 2560 2561 SYSINIT(vfs_devfs_register, SI_SUB_PRE_DRIVERS, SI_ORDER_FIRST, 2562 devfs_init, NULL); 2563 SYSUNINIT(vfs_devfs_register, SI_SUB_PRE_DRIVERS, SI_ORDER_ANY, 2564 devfs_uninit, NULL); 2565 2566 /* 2567 * WildCmp() - compare wild string to sane string 2568 * 2569 * Returns 0 on success, -1 on failure. 2570 */ 2571 static int 2572 wildCmp(const char **mary, int d, const char *w, const char *s) 2573 { 2574 int i; 2575 2576 /* 2577 * skip fixed portion 2578 */ 2579 for (;;) { 2580 switch(*w) { 2581 case '*': 2582 /* 2583 * optimize terminator 2584 */ 2585 if (w[1] == 0) 2586 return(0); 2587 if (w[1] != '?' && w[1] != '*') { 2588 /* 2589 * optimize * followed by non-wild 2590 */ 2591 for (i = 0; s + i < mary[d]; ++i) { 2592 if (s[i] == w[1] && wildCmp(mary, d + 1, w + 1, s + i) == 0) 2593 return(0); 2594 } 2595 } else { 2596 /* 2597 * less-optimal 2598 */ 2599 for (i = 0; s + i < mary[d]; ++i) { 2600 if (wildCmp(mary, d + 1, w + 1, s + i) == 0) 2601 return(0); 2602 } 2603 } 2604 mary[d] = s; 2605 return(-1); 2606 case '?': 2607 if (*s == 0) 2608 return(-1); 2609 ++w; 2610 ++s; 2611 break; 2612 default: 2613 if (*w != *s) 2614 return(-1); 2615 if (*w == 0) /* terminator */ 2616 return(0); 2617 ++w; 2618 ++s; 2619 break; 2620 } 2621 } 2622 /* not reached */ 2623 return(-1); 2624 } 2625 2626 2627 /* 2628 * WildCaseCmp() - compare wild string to sane string, case insensitive 2629 * 2630 * Returns 0 on success, -1 on failure. 2631 */ 2632 static int 2633 wildCaseCmp(const char **mary, int d, const char *w, const char *s) 2634 { 2635 int i; 2636 2637 /* 2638 * skip fixed portion 2639 */ 2640 for (;;) { 2641 switch(*w) { 2642 case '*': 2643 /* 2644 * optimize terminator 2645 */ 2646 if (w[1] == 0) 2647 return(0); 2648 if (w[1] != '?' && w[1] != '*') { 2649 /* 2650 * optimize * followed by non-wild 2651 */ 2652 for (i = 0; s + i < mary[d]; ++i) { 2653 if (s[i] == w[1] && wildCaseCmp(mary, d + 1, w + 1, s + i) == 0) 2654 return(0); 2655 } 2656 } else { 2657 /* 2658 * less-optimal 2659 */ 2660 for (i = 0; s + i < mary[d]; ++i) { 2661 if (wildCaseCmp(mary, d + 1, w + 1, s + i) == 0) 2662 return(0); 2663 } 2664 } 2665 mary[d] = s; 2666 return(-1); 2667 case '?': 2668 if (*s == 0) 2669 return(-1); 2670 ++w; 2671 ++s; 2672 break; 2673 default: 2674 if (*w != *s) { 2675 #define tolower(x) ((x >= 'A' && x <= 'Z')?(x+('a'-'A')):(x)) 2676 if (tolower(*w) != tolower(*s)) 2677 return(-1); 2678 } 2679 if (*w == 0) /* terminator */ 2680 return(0); 2681 ++w; 2682 ++s; 2683 break; 2684 } 2685 } 2686 /* not reached */ 2687 return(-1); 2688 } 2689 2690 int 2691 devfs_WildCmp(const char *w, const char *s) 2692 { 2693 int i; 2694 int c; 2695 int slen = strlen(s); 2696 const char **mary; 2697 2698 for (i = c = 0; w[i]; ++i) { 2699 if (w[i] == '*') 2700 ++c; 2701 } 2702 mary = kmalloc(sizeof(char *) * (c + 1), M_DEVFS, M_WAITOK); 2703 for (i = 0; i < c; ++i) 2704 mary[i] = s + slen; 2705 i = wildCmp(mary, 0, w, s); 2706 kfree(mary, M_DEVFS); 2707 return(i); 2708 } 2709 2710 int 2711 devfs_WildCaseCmp(const char *w, const char *s) 2712 { 2713 int i; 2714 int c; 2715 int slen = strlen(s); 2716 const char **mary; 2717 2718 for (i = c = 0; w[i]; ++i) { 2719 if (w[i] == '*') 2720 ++c; 2721 } 2722 mary = kmalloc(sizeof(char *) * (c + 1), M_DEVFS, M_WAITOK); 2723 for (i = 0; i < c; ++i) 2724 mary[i] = s + slen; 2725 i = wildCaseCmp(mary, 0, w, s); 2726 kfree(mary, M_DEVFS); 2727 return(i); 2728 } 2729 2730