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/bus.h> 38 #include <sys/mount.h> 39 #include <sys/vnode.h> 40 #include <sys/types.h> 41 #include <sys/lock.h> 42 #include <sys/file.h> 43 #include <sys/msgport.h> 44 #include <sys/sysctl.h> 45 #include <sys/ucred.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/sysref2.h> 53 54 MALLOC_DEFINE(M_DEVFS, "devfs", "Device File System (devfs) allocations"); 55 DEVFS_DEFINE_CLONE_BITMAP(ops_id); 56 /* 57 * SYSREF Integration - reference counting, allocation, 58 * sysid and syslink integration. 59 */ 60 static void devfs_cdev_terminate(cdev_t dev); 61 static void devfs_cdev_lock(cdev_t dev); 62 static void devfs_cdev_unlock(cdev_t dev); 63 static struct sysref_class cdev_sysref_class = { 64 .name = "cdev", 65 .mtype = M_DEVFS, 66 .proto = SYSREF_PROTO_DEV, 67 .offset = offsetof(struct cdev, si_sysref), 68 .objsize = sizeof(struct cdev), 69 .nom_cache = 32, 70 .flags = 0, 71 .ops = { 72 .terminate = (sysref_terminate_func_t)devfs_cdev_terminate, 73 .lock = (sysref_lock_func_t)devfs_cdev_lock, 74 .unlock = (sysref_unlock_func_t)devfs_cdev_unlock 75 } 76 }; 77 78 static struct objcache *devfs_node_cache; 79 static struct objcache *devfs_msg_cache; 80 static struct objcache *devfs_dev_cache; 81 82 static struct objcache_malloc_args devfs_node_malloc_args = { 83 sizeof(struct devfs_node), M_DEVFS }; 84 struct objcache_malloc_args devfs_msg_malloc_args = { 85 sizeof(struct devfs_msg), M_DEVFS }; 86 struct objcache_malloc_args devfs_dev_malloc_args = { 87 sizeof(struct cdev), M_DEVFS }; 88 89 static struct devfs_dev_head devfs_dev_list = 90 TAILQ_HEAD_INITIALIZER(devfs_dev_list); 91 static struct devfs_mnt_head devfs_mnt_list = 92 TAILQ_HEAD_INITIALIZER(devfs_mnt_list); 93 static struct devfs_chandler_head devfs_chandler_list = 94 TAILQ_HEAD_INITIALIZER(devfs_chandler_list); 95 static struct devfs_alias_head devfs_alias_list = 96 TAILQ_HEAD_INITIALIZER(devfs_alias_list); 97 static struct devfs_dev_ops_head devfs_dev_ops_list = 98 TAILQ_HEAD_INITIALIZER(devfs_dev_ops_list); 99 100 struct lock devfs_lock; 101 struct lwkt_token devfs_token; 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_related_worker(cdev_t); 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_related_flag_worker(cdev_t, uint32_t); 146 static int devfs_destroy_related_without_flag_worker(cdev_t, 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 Nroot: 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 Ndir: 215 TAILQ_INIT(DEVFS_DENODE_HEAD(node)); 216 node->d_dir.d_type = DT_DIR; 217 node->nchildren = 2; 218 break; 219 220 case Nlink: 221 node->d_dir.d_type = DT_LNK; 222 break; 223 224 case Nreg: 225 node->d_dir.d_type = DT_REG; 226 break; 227 228 case Ndev: 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 == Nroot) || (parent->node_type == Ndir))) { 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 /* 277 * Apply rules (requires root node, skip if we are creating the root node) 278 */ 279 if (DEVFS_MNTDATA(mp)->root_node) 280 devfs_rule_check_apply(node, NULL); 281 282 atomic_add_long(&DEVFS_MNTDATA(mp)->file_count, 1); 283 284 return node; 285 } 286 287 /* 288 * devfs_allocv() allocates a new vnode based on a devfs node. 289 */ 290 int 291 devfs_allocv(struct vnode **vpp, struct devfs_node *node) 292 { 293 struct vnode *vp; 294 int error = 0; 295 296 KKASSERT(node); 297 298 /* 299 * devfs master lock must not be held across a vget() call, we have 300 * to hold our ad-hoc vp to avoid a free race from destroying the 301 * contents of the structure. The vget() will interlock recycles 302 * for us. 303 */ 304 try_again: 305 while ((vp = node->v_node) != NULL) { 306 vhold(vp); 307 lockmgr(&devfs_lock, LK_RELEASE); 308 error = vget(vp, LK_EXCLUSIVE); 309 vdrop(vp); 310 lockmgr(&devfs_lock, LK_EXCLUSIVE); 311 if (error == 0) { 312 *vpp = vp; 313 goto out; 314 } 315 if (error != ENOENT) { 316 *vpp = NULL; 317 goto out; 318 } 319 } 320 321 /* 322 * devfs master lock must not be held across a getnewvnode() call. 323 */ 324 lockmgr(&devfs_lock, LK_RELEASE); 325 if ((error = getnewvnode(VT_DEVFS, node->mp, vpp, 0, 0)) != 0) { 326 lockmgr(&devfs_lock, LK_EXCLUSIVE); 327 goto out; 328 } 329 lockmgr(&devfs_lock, LK_EXCLUSIVE); 330 331 vp = *vpp; 332 333 if (node->v_node != NULL) { 334 vp->v_type = VBAD; 335 vx_put(vp); 336 goto try_again; 337 } 338 339 vp->v_data = node; 340 node->v_node = vp; 341 342 switch (node->node_type) { 343 case Nroot: 344 vsetflags(vp, VROOT); 345 /* fall through */ 346 case Ndir: 347 vp->v_type = VDIR; 348 break; 349 350 case Nlink: 351 vp->v_type = VLNK; 352 break; 353 354 case Nreg: 355 vp->v_type = VREG; 356 break; 357 358 case Ndev: 359 vp->v_type = VCHR; 360 KKASSERT(node->d_dev); 361 362 vp->v_uminor = node->d_dev->si_uminor; 363 vp->v_umajor = node->d_dev->si_umajor; 364 365 v_associate_rdev(vp, node->d_dev); 366 vp->v_ops = &node->mp->mnt_vn_spec_ops; 367 if (node->d_dev->si_ops->head.flags & D_KVABIO) 368 vsetflags(vp, VKVABIO); 369 break; 370 371 default: 372 panic("devfs_allocv: unknown node type"); 373 } 374 375 out: 376 return error; 377 } 378 379 /* 380 * devfs_allocvp allocates both a devfs node (with the given settings) and a vnode 381 * based on the newly created devfs node. 382 */ 383 int 384 devfs_allocvp(struct mount *mp, struct vnode **vpp, devfs_nodetype devfsnodetype, 385 char *name, struct devfs_node *parent, cdev_t dev) 386 { 387 struct devfs_node *node; 388 389 node = devfs_allocp(devfsnodetype, name, parent, mp, dev); 390 391 if (node != NULL) 392 devfs_allocv(vpp, node); 393 else 394 *vpp = NULL; 395 396 return 0; 397 } 398 399 /* 400 * Destroy the devfs_node. The node must be unlinked from the topology. 401 * 402 * This function will also destroy any vnode association with the node 403 * and device. 404 * 405 * The cdev_t itself remains intact. 406 * 407 * The core lock is not necessarily held on call and must be temporarily 408 * released if it is to avoid a deadlock. 409 */ 410 int 411 devfs_freep(struct devfs_node *node) 412 { 413 struct vnode *vp; 414 int relock; 415 416 KKASSERT(node); 417 KKASSERT(((node->flags & DEVFS_NODE_LINKED) == 0) || 418 (node->node_type == Nroot)); 419 420 /* 421 * Protect against double frees 422 */ 423 KKASSERT((node->flags & DEVFS_DESTROYED) == 0); 424 node->flags |= DEVFS_DESTROYED; 425 426 /* 427 * Avoid deadlocks between devfs_lock and the vnode lock when 428 * disassociating the vnode (stress2 pty vs ls -la /dev/pts). 429 * 430 * This also prevents the vnode reclaim code from double-freeing 431 * the node. The vget() is required to safely modified the vp 432 * and cycle the refs to terminate an inactive vp. 433 */ 434 if (lockstatus(&devfs_lock, curthread) == LK_EXCLUSIVE) { 435 lockmgr(&devfs_lock, LK_RELEASE); 436 relock = 1; 437 } else { 438 relock = 0; 439 } 440 441 while ((vp = node->v_node) != NULL) { 442 if (vget(vp, LK_EXCLUSIVE | LK_RETRY) != 0) 443 break; 444 v_release_rdev(vp); 445 vp->v_data = NULL; 446 node->v_node = NULL; 447 vput(vp); 448 } 449 450 /* 451 * Remaining cleanup 452 */ 453 atomic_subtract_long(&DEVFS_MNTDATA(node->mp)->leak_count, 1); 454 if (node->symlink_name) { 455 kfree(node->symlink_name, M_DEVFS); 456 node->symlink_name = NULL; 457 } 458 459 /* 460 * Remove the node from the orphan list if it is still on it. 461 */ 462 if (node->flags & DEVFS_ORPHANED) 463 devfs_tracer_del_orphan(node); 464 465 if (node->d_dir.d_name) { 466 kfree(node->d_dir.d_name, M_DEVFS); 467 node->d_dir.d_name = NULL; 468 } 469 atomic_subtract_long(&DEVFS_MNTDATA(node->mp)->file_count, 1); 470 objcache_put(devfs_node_cache, node); 471 472 if (relock) 473 lockmgr(&devfs_lock, LK_EXCLUSIVE); 474 475 return 0; 476 } 477 478 /* 479 * Returns a valid vp associated with the devfs alias node or NULL 480 */ 481 static void *devfs_alias_getvp(struct devfs_node *node) 482 { 483 struct devfs_node *found = node; 484 int depth = 0; 485 486 while ((found->node_type == Nlink) && (found->link_target)) { 487 if (depth >= 8) { 488 devfs_debug(DEVFS_DEBUG_SHOW, "Recursive link or depth >= 8"); 489 break; 490 } 491 492 found = found->link_target; 493 ++depth; 494 } 495 496 return found->v_node; 497 } 498 499 /* 500 * Unlink the devfs node from the topology and add it to the orphan list. 501 * The node will later be destroyed by freep. 502 * 503 * Any vnode association, including the v_rdev and v_data, remains intact 504 * until the freep. 505 */ 506 int 507 devfs_unlinkp(struct devfs_node *node) 508 { 509 struct vnode *vp; 510 struct devfs_node *parent; 511 KKASSERT(node); 512 513 /* 514 * Add the node to the orphan list, so it is referenced somewhere, to 515 * so we don't leak it. 516 */ 517 devfs_tracer_add_orphan(node); 518 519 parent = node->parent; 520 521 /* 522 * If the parent is known we can unlink the node out of the topology 523 */ 524 if (parent) { 525 TAILQ_REMOVE(DEVFS_DENODE_HEAD(parent), node, link); 526 parent->nchildren--; 527 node->flags &= ~DEVFS_NODE_LINKED; 528 } 529 530 node->parent = NULL; 531 532 /* 533 * Namecache invalidation. 534 * devfs alias nodes are special: their v_node entry is always null 535 * and they use the one from their link target. 536 * We thus use the target node's vp to invalidate both alias and target 537 * entries in the namecache. 538 * Doing so for the target is not necessary but it would be more 539 * expensive to resolve only the namecache entry of the alias node 540 * from the information available in this function. 541 */ 542 if (node->node_type == Nlink) 543 vp = devfs_alias_getvp(node); 544 else 545 vp = node->v_node; 546 547 if (vp != NULL) 548 cache_inval_vp(vp, CINV_DESTROY); 549 550 return 0; 551 } 552 553 void * 554 devfs_iterate_topology(struct devfs_node *node, 555 devfs_iterate_callback_t *callback, void *arg1) 556 { 557 struct devfs_node *node1, *node2; 558 void *ret = NULL; 559 560 if ((node->node_type == Nroot) || (node->node_type == Ndir)) { 561 if (node->nchildren > 2) { 562 TAILQ_FOREACH_MUTABLE(node1, DEVFS_DENODE_HEAD(node), 563 link, node2) { 564 if ((ret = devfs_iterate_topology(node1, callback, arg1))) 565 return ret; 566 } 567 } 568 } 569 570 ret = callback(node, arg1); 571 return ret; 572 } 573 574 static void * 575 devfs_alias_reaper_callback(struct devfs_node *node, void *unused) 576 { 577 if (node->node_type == Nlink) { 578 devfs_unlinkp(node); 579 devfs_freep(node); 580 } 581 582 return NULL; 583 } 584 585 /* 586 * devfs_reaperp() is a recursive function that iterates through all the 587 * topology, unlinking and freeing all devfs nodes. 588 */ 589 static void * 590 devfs_reaperp_callback(struct devfs_node *node, void *unused) 591 { 592 devfs_unlinkp(node); 593 devfs_freep(node); 594 595 return NULL; 596 } 597 598 static void * 599 devfs_gc_dirs_callback(struct devfs_node *node, void *unused) 600 { 601 if (node->node_type == Ndir) { 602 if ((node->nchildren == 2) && 603 !(node->flags & DEVFS_USER_CREATED)) { 604 devfs_unlinkp(node); 605 devfs_freep(node); 606 } 607 } 608 609 return NULL; 610 } 611 612 static void * 613 devfs_gc_links_callback(struct devfs_node *node, struct devfs_node *target) 614 { 615 if ((node->node_type == Nlink) && (node->link_target == target)) { 616 devfs_unlinkp(node); 617 devfs_freep(node); 618 } 619 620 return NULL; 621 } 622 623 /* 624 * devfs_gc() is devfs garbage collector. It takes care of unlinking and 625 * freeing a node, but also removes empty directories and links that link 626 * via devfs auto-link mechanism to the node being deleted. 627 */ 628 int 629 devfs_gc(struct devfs_node *node) 630 { 631 struct devfs_node *root_node = DEVFS_MNTDATA(node->mp)->root_node; 632 633 if (node->nlinks > 0) 634 devfs_iterate_topology(root_node, 635 (devfs_iterate_callback_t *)devfs_gc_links_callback, node); 636 637 devfs_unlinkp(node); 638 devfs_iterate_topology(root_node, 639 (devfs_iterate_callback_t *)devfs_gc_dirs_callback, NULL); 640 641 devfs_freep(node); 642 643 return 0; 644 } 645 646 /* 647 * devfs_create_dev() is the asynchronous entry point for device creation. 648 * It just sends a message with the relevant details to the devfs core. 649 * 650 * This function will reference the passed device. The reference is owned 651 * by devfs and represents all of the device's node associations. 652 */ 653 int 654 devfs_create_dev(cdev_t dev, uid_t uid, gid_t gid, int perms) 655 { 656 reference_dev(dev); 657 devfs_msg_send_dev(DEVFS_DEVICE_CREATE, dev, uid, gid, perms); 658 659 return 0; 660 } 661 662 /* 663 * devfs_destroy_dev() is the asynchronous entry point for device destruction. 664 * It just sends a message with the relevant details to the devfs core. 665 */ 666 int 667 devfs_destroy_dev(cdev_t dev) 668 { 669 devfs_msg_send_dev(DEVFS_DEVICE_DESTROY, dev, 0, 0, 0); 670 return 0; 671 } 672 673 /* 674 * devfs_mount_add() is the synchronous entry point for adding a new devfs 675 * mount. It sends a synchronous message with the relevant details to the 676 * devfs core. 677 */ 678 int 679 devfs_mount_add(struct devfs_mnt_data *mnt) 680 { 681 devfs_msg_t msg; 682 683 msg = devfs_msg_get(); 684 msg->mdv_mnt = mnt; 685 devfs_msg_send_sync(DEVFS_MOUNT_ADD, msg); 686 devfs_msg_put(msg); 687 688 return 0; 689 } 690 691 /* 692 * devfs_mount_del() is the synchronous entry point for removing a devfs mount. 693 * It sends a synchronous message with the relevant details to the devfs core. 694 */ 695 int 696 devfs_mount_del(struct devfs_mnt_data *mnt) 697 { 698 devfs_msg_t msg; 699 700 msg = devfs_msg_get(); 701 msg->mdv_mnt = mnt; 702 devfs_msg_send_sync(DEVFS_MOUNT_DEL, msg); 703 devfs_msg_put(msg); 704 705 return 0; 706 } 707 708 /* 709 * devfs_destroy_related() is the synchronous entry point for device 710 * destruction by subname. It just sends a message with the relevant details to 711 * the devfs core. 712 */ 713 int 714 devfs_destroy_related(cdev_t dev) 715 { 716 devfs_msg_t msg; 717 718 msg = devfs_msg_get(); 719 msg->mdv_load = dev; 720 devfs_msg_send_sync(DEVFS_DESTROY_RELATED, msg); 721 devfs_msg_put(msg); 722 return 0; 723 } 724 725 int 726 devfs_clr_related_flag(cdev_t dev, uint32_t flag) 727 { 728 devfs_msg_t msg; 729 730 msg = devfs_msg_get(); 731 msg->mdv_flags.dev = dev; 732 msg->mdv_flags.flag = flag; 733 devfs_msg_send_sync(DEVFS_CLR_RELATED_FLAG, msg); 734 devfs_msg_put(msg); 735 736 return 0; 737 } 738 739 int 740 devfs_destroy_related_without_flag(cdev_t dev, uint32_t flag) 741 { 742 devfs_msg_t msg; 743 744 msg = devfs_msg_get(); 745 msg->mdv_flags.dev = dev; 746 msg->mdv_flags.flag = flag; 747 devfs_msg_send_sync(DEVFS_DESTROY_RELATED_WO_FLAG, msg); 748 devfs_msg_put(msg); 749 750 return 0; 751 } 752 753 /* 754 * devfs_create_all_dev is the asynchronous entry point to trigger device 755 * node creation. It just sends a message with the relevant details to 756 * the devfs core. 757 */ 758 int 759 devfs_create_all_dev(struct devfs_node *root) 760 { 761 devfs_msg_send_generic(DEVFS_CREATE_ALL_DEV, root); 762 return 0; 763 } 764 765 /* 766 * devfs_destroy_dev_by_ops is the asynchronous entry point to destroy all 767 * devices with a specific set of dev_ops and minor. It just sends a 768 * message with the relevant details to the devfs core. 769 */ 770 int 771 devfs_destroy_dev_by_ops(struct dev_ops *ops, int minor) 772 { 773 devfs_msg_send_ops(DEVFS_DESTROY_DEV_BY_OPS, ops, minor); 774 return 0; 775 } 776 777 /* 778 * devfs_clone_handler_add is the synchronous entry point to add a new 779 * clone handler. It just sends a message with the relevant details to 780 * the devfs core. 781 */ 782 int 783 devfs_clone_handler_add(const char *name, d_clone_t *nhandler) 784 { 785 devfs_msg_t msg; 786 787 msg = devfs_msg_get(); 788 msg->mdv_chandler.name = name; 789 msg->mdv_chandler.nhandler = nhandler; 790 devfs_msg_send_sync(DEVFS_CHANDLER_ADD, msg); 791 devfs_msg_put(msg); 792 return 0; 793 } 794 795 /* 796 * devfs_clone_handler_del is the synchronous entry point to remove a 797 * clone handler. It just sends a message with the relevant details to 798 * the devfs core. 799 */ 800 int 801 devfs_clone_handler_del(const char *name) 802 { 803 devfs_msg_t msg; 804 805 msg = devfs_msg_get(); 806 msg->mdv_chandler.name = name; 807 msg->mdv_chandler.nhandler = NULL; 808 devfs_msg_send_sync(DEVFS_CHANDLER_DEL, msg); 809 devfs_msg_put(msg); 810 return 0; 811 } 812 813 /* 814 * devfs_find_device_by_name is the synchronous entry point to find a 815 * device given its name. It sends a synchronous message with the 816 * relevant details to the devfs core and returns the answer. 817 */ 818 cdev_t 819 devfs_find_device_by_name(const char *fmt, ...) 820 { 821 cdev_t found = NULL; 822 devfs_msg_t msg; 823 char *target; 824 __va_list ap; 825 826 if (fmt == NULL) 827 return NULL; 828 829 __va_start(ap, fmt); 830 kvasnrprintf(&target, PATH_MAX, 10, fmt, ap); 831 __va_end(ap); 832 833 msg = devfs_msg_get(); 834 msg->mdv_name = target; 835 devfs_msg_send_sync(DEVFS_FIND_DEVICE_BY_NAME, msg); 836 found = msg->mdv_cdev; 837 devfs_msg_put(msg); 838 kvasfree(&target); 839 840 return found; 841 } 842 843 /* 844 * devfs_find_device_by_udev is the synchronous entry point to find a 845 * device given its udev number. It sends a synchronous message with 846 * the relevant details to the devfs core and returns the answer. 847 */ 848 cdev_t 849 devfs_find_device_by_udev(udev_t udev) 850 { 851 cdev_t found = NULL; 852 devfs_msg_t msg; 853 854 msg = devfs_msg_get(); 855 msg->mdv_udev = udev; 856 devfs_msg_send_sync(DEVFS_FIND_DEVICE_BY_UDEV, msg); 857 found = msg->mdv_cdev; 858 devfs_msg_put(msg); 859 860 devfs_debug(DEVFS_DEBUG_DEBUG, 861 "devfs_find_device_by_udev found? %s -end:3-\n", 862 ((found) ? found->si_name:"NO")); 863 return found; 864 } 865 866 struct vnode * 867 devfs_inode_to_vnode(struct mount *mp, ino_t target) 868 { 869 struct vnode *vp = NULL; 870 devfs_msg_t msg; 871 872 if (mp == NULL) 873 return NULL; 874 875 msg = devfs_msg_get(); 876 msg->mdv_ino.mp = mp; 877 msg->mdv_ino.ino = target; 878 devfs_msg_send_sync(DEVFS_INODE_TO_VNODE, msg); 879 vp = msg->mdv_ino.vp; 880 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 881 devfs_msg_put(msg); 882 883 return vp; 884 } 885 886 /* 887 * devfs_make_alias is the asynchronous entry point to register an alias 888 * for a device. It just sends a message with the relevant details to the 889 * devfs core. 890 */ 891 int 892 devfs_make_alias(const char *name, cdev_t dev_target) 893 { 894 struct devfs_alias *alias; 895 size_t len; 896 897 len = strlen(name); 898 899 alias = kmalloc(sizeof(struct devfs_alias), M_DEVFS, M_WAITOK); 900 alias->name = kstrdup(name, M_DEVFS); 901 alias->namlen = len; 902 alias->dev_target = dev_target; 903 904 devfs_msg_send_generic(DEVFS_MAKE_ALIAS, alias); 905 return 0; 906 } 907 908 /* 909 * devfs_destroy_alias is the asynchronous entry point to deregister an alias 910 * for a device. It just sends a message with the relevant details to the 911 * devfs core. 912 */ 913 int 914 devfs_destroy_alias(const char *name, cdev_t dev_target) 915 { 916 struct devfs_alias *alias; 917 size_t len; 918 919 len = strlen(name); 920 921 alias = kmalloc(sizeof(struct devfs_alias), M_DEVFS, M_WAITOK); 922 alias->name = kstrdup(name, M_DEVFS); 923 alias->namlen = len; 924 alias->dev_target = dev_target; 925 926 devfs_msg_send_generic(DEVFS_DESTROY_ALIAS, alias); 927 return 0; 928 } 929 930 /* 931 * devfs_apply_rules is the asynchronous entry point to trigger application 932 * of all rules. It just sends a message with the relevant details to the 933 * devfs core. 934 */ 935 int 936 devfs_apply_rules(char *mntto) 937 { 938 char *new_name; 939 940 new_name = kstrdup(mntto, M_DEVFS); 941 devfs_msg_send_name(DEVFS_APPLY_RULES, new_name); 942 943 return 0; 944 } 945 946 /* 947 * devfs_reset_rules is the asynchronous entry point to trigger reset of all 948 * rules. It just sends a message with the relevant details to the devfs core. 949 */ 950 int 951 devfs_reset_rules(char *mntto) 952 { 953 char *new_name; 954 955 new_name = kstrdup(mntto, M_DEVFS); 956 devfs_msg_send_name(DEVFS_RESET_RULES, new_name); 957 958 return 0; 959 } 960 961 962 /* 963 * devfs_scan_callback is the asynchronous entry point to call a callback 964 * on all cdevs. 965 * It just sends a message with the relevant details to the devfs core. 966 */ 967 int 968 devfs_scan_callback(devfs_scan_t *callback, void *arg) 969 { 970 devfs_msg_t msg; 971 972 KKASSERT(callback); 973 974 msg = devfs_msg_get(); 975 msg->mdv_load = callback; 976 msg->mdv_load2 = arg; 977 devfs_msg_send_sync(DEVFS_SCAN_CALLBACK, msg); 978 devfs_msg_put(msg); 979 980 return 0; 981 } 982 983 984 /* 985 * Acts as a message drain. Any message that is replied to here gets destroyed 986 * and the memory freed. 987 */ 988 static void 989 devfs_msg_autofree_reply(lwkt_port_t port, lwkt_msg_t msg) 990 { 991 devfs_msg_put((devfs_msg_t)msg); 992 } 993 994 /* 995 * devfs_msg_get allocates a new devfs msg and returns it. 996 */ 997 devfs_msg_t 998 devfs_msg_get(void) 999 { 1000 return objcache_get(devfs_msg_cache, M_WAITOK); 1001 } 1002 1003 /* 1004 * devfs_msg_put deallocates a given devfs msg. 1005 */ 1006 int 1007 devfs_msg_put(devfs_msg_t msg) 1008 { 1009 objcache_put(devfs_msg_cache, msg); 1010 return 0; 1011 } 1012 1013 /* 1014 * devfs_msg_send is the generic asynchronous message sending facility 1015 * for devfs. By default the reply port is the automatic disposal port. 1016 * 1017 * If the current thread is the devfs_msg_port thread we execute the 1018 * operation synchronously. 1019 */ 1020 void 1021 devfs_msg_send(uint32_t cmd, devfs_msg_t devfs_msg) 1022 { 1023 lwkt_port_t port = &devfs_msg_port; 1024 1025 lwkt_initmsg(&devfs_msg->hdr, &devfs_dispose_port, 0); 1026 1027 devfs_msg->hdr.u.ms_result = cmd; 1028 1029 if (port->mpu_td == curthread) { 1030 devfs_msg_exec(devfs_msg); 1031 lwkt_replymsg(&devfs_msg->hdr, 0); 1032 } else { 1033 lwkt_sendmsg(port, (lwkt_msg_t)devfs_msg); 1034 } 1035 } 1036 1037 /* 1038 * devfs_msg_send_sync is the generic synchronous message sending 1039 * facility for devfs. It initializes a local reply port and waits 1040 * for the core's answer. The core will write the answer on the same 1041 * message which is sent back as reply. The caller still has a reference 1042 * to the message, so we don't need to return it. 1043 */ 1044 int 1045 devfs_msg_send_sync(uint32_t cmd, devfs_msg_t devfs_msg) 1046 { 1047 struct lwkt_port rep_port; 1048 int error; 1049 lwkt_port_t port = &devfs_msg_port; 1050 1051 lwkt_initport_thread(&rep_port, curthread); 1052 lwkt_initmsg(&devfs_msg->hdr, &rep_port, 0); 1053 1054 devfs_msg->hdr.u.ms_result = cmd; 1055 1056 error = lwkt_domsg(port, (lwkt_msg_t)devfs_msg, 0); 1057 1058 return error; 1059 } 1060 1061 /* 1062 * sends a message with a generic argument. 1063 */ 1064 void 1065 devfs_msg_send_generic(uint32_t cmd, void *load) 1066 { 1067 devfs_msg_t devfs_msg = devfs_msg_get(); 1068 1069 devfs_msg->mdv_load = load; 1070 devfs_msg_send(cmd, devfs_msg); 1071 } 1072 1073 /* 1074 * sends a message with a name argument. 1075 */ 1076 void 1077 devfs_msg_send_name(uint32_t cmd, char *name) 1078 { 1079 devfs_msg_t devfs_msg = devfs_msg_get(); 1080 1081 devfs_msg->mdv_name = name; 1082 devfs_msg_send(cmd, devfs_msg); 1083 } 1084 1085 /* 1086 * sends a message with a mount argument. 1087 */ 1088 void 1089 devfs_msg_send_mount(uint32_t cmd, struct devfs_mnt_data *mnt) 1090 { 1091 devfs_msg_t devfs_msg = devfs_msg_get(); 1092 1093 devfs_msg->mdv_mnt = mnt; 1094 devfs_msg_send(cmd, devfs_msg); 1095 } 1096 1097 /* 1098 * sends a message with an ops argument. 1099 */ 1100 void 1101 devfs_msg_send_ops(uint32_t cmd, struct dev_ops *ops, int minor) 1102 { 1103 devfs_msg_t devfs_msg = devfs_msg_get(); 1104 1105 devfs_msg->mdv_ops.ops = ops; 1106 devfs_msg->mdv_ops.minor = minor; 1107 devfs_msg_send(cmd, devfs_msg); 1108 } 1109 1110 /* 1111 * sends a message with a clone handler argument. 1112 */ 1113 void 1114 devfs_msg_send_chandler(uint32_t cmd, char *name, d_clone_t handler) 1115 { 1116 devfs_msg_t devfs_msg = devfs_msg_get(); 1117 1118 devfs_msg->mdv_chandler.name = name; 1119 devfs_msg->mdv_chandler.nhandler = handler; 1120 devfs_msg_send(cmd, devfs_msg); 1121 } 1122 1123 /* 1124 * sends a message with a device argument. 1125 */ 1126 void 1127 devfs_msg_send_dev(uint32_t cmd, cdev_t dev, uid_t uid, gid_t gid, int perms) 1128 { 1129 devfs_msg_t devfs_msg = devfs_msg_get(); 1130 1131 devfs_msg->mdv_dev.dev = dev; 1132 devfs_msg->mdv_dev.uid = uid; 1133 devfs_msg->mdv_dev.gid = gid; 1134 devfs_msg->mdv_dev.perms = perms; 1135 1136 devfs_msg_send(cmd, devfs_msg); 1137 } 1138 1139 /* 1140 * sends a message with a link argument. 1141 */ 1142 void 1143 devfs_msg_send_link(uint32_t cmd, char *name, char *target, struct mount *mp) 1144 { 1145 devfs_msg_t devfs_msg = devfs_msg_get(); 1146 1147 devfs_msg->mdv_link.name = name; 1148 devfs_msg->mdv_link.target = target; 1149 devfs_msg->mdv_link.mp = mp; 1150 devfs_msg_send(cmd, devfs_msg); 1151 } 1152 1153 /* 1154 * devfs_msg_core is the main devfs thread. It handles all incoming messages 1155 * and calls the relevant worker functions. By using messages it's assured 1156 * that events occur in the correct order. 1157 */ 1158 static void 1159 devfs_msg_core(void *arg) 1160 { 1161 devfs_msg_t msg; 1162 1163 lwkt_initport_thread(&devfs_msg_port, curthread); 1164 1165 lockmgr(&devfs_lock, LK_EXCLUSIVE); 1166 devfs_run = 1; 1167 wakeup(td_core); 1168 lockmgr(&devfs_lock, LK_RELEASE); 1169 1170 lwkt_gettoken(&devfs_token); 1171 1172 while (devfs_run) { 1173 msg = (devfs_msg_t)lwkt_waitport(&devfs_msg_port, 0); 1174 devfs_debug(DEVFS_DEBUG_DEBUG, 1175 "devfs_msg_core, new msg: %x\n", 1176 (unsigned int)msg->hdr.u.ms_result); 1177 devfs_msg_exec(msg); 1178 lwkt_replymsg(&msg->hdr, 0); 1179 } 1180 1181 lwkt_reltoken(&devfs_token); 1182 wakeup(td_core); 1183 1184 lwkt_exit(); 1185 } 1186 1187 static void 1188 devfs_msg_exec(devfs_msg_t msg) 1189 { 1190 struct devfs_mnt_data *mnt; 1191 struct devfs_node *node; 1192 cdev_t dev; 1193 1194 /* 1195 * Acquire the devfs lock to ensure safety of all called functions 1196 */ 1197 lockmgr(&devfs_lock, LK_EXCLUSIVE); 1198 1199 switch (msg->hdr.u.ms_result) { 1200 case DEVFS_DEVICE_CREATE: 1201 dev = msg->mdv_dev.dev; 1202 devfs_create_dev_worker(dev, 1203 msg->mdv_dev.uid, 1204 msg->mdv_dev.gid, 1205 msg->mdv_dev.perms); 1206 break; 1207 case DEVFS_DEVICE_DESTROY: 1208 dev = msg->mdv_dev.dev; 1209 devfs_destroy_dev_worker(dev); 1210 break; 1211 case DEVFS_DESTROY_RELATED: 1212 devfs_destroy_related_worker(msg->mdv_load); 1213 break; 1214 case DEVFS_DESTROY_DEV_BY_OPS: 1215 devfs_destroy_dev_by_ops_worker(msg->mdv_ops.ops, 1216 msg->mdv_ops.minor); 1217 break; 1218 case DEVFS_CREATE_ALL_DEV: 1219 node = (struct devfs_node *)msg->mdv_load; 1220 devfs_create_all_dev_worker(node); 1221 break; 1222 case DEVFS_MOUNT_ADD: 1223 mnt = msg->mdv_mnt; 1224 TAILQ_INSERT_TAIL(&devfs_mnt_list, mnt, link); 1225 devfs_create_all_dev_worker(mnt->root_node); 1226 break; 1227 case DEVFS_MOUNT_DEL: 1228 mnt = msg->mdv_mnt; 1229 TAILQ_REMOVE(&devfs_mnt_list, mnt, link); 1230 /* Be sure to remove all the aliases first */ 1231 devfs_iterate_topology(mnt->root_node, devfs_alias_reaper_callback, 1232 NULL); 1233 devfs_iterate_topology(mnt->root_node, devfs_reaperp_callback, 1234 NULL); 1235 if (mnt->leak_count) { 1236 devfs_debug(DEVFS_DEBUG_SHOW, 1237 "Leaked %ld devfs_node elements!\n", 1238 mnt->leak_count); 1239 } 1240 break; 1241 case DEVFS_CHANDLER_ADD: 1242 devfs_chandler_add_worker(msg->mdv_chandler.name, 1243 msg->mdv_chandler.nhandler); 1244 break; 1245 case DEVFS_CHANDLER_DEL: 1246 devfs_chandler_del_worker(msg->mdv_chandler.name); 1247 break; 1248 case DEVFS_FIND_DEVICE_BY_NAME: 1249 devfs_find_device_by_name_worker(msg); 1250 break; 1251 case DEVFS_FIND_DEVICE_BY_UDEV: 1252 devfs_find_device_by_udev_worker(msg); 1253 break; 1254 case DEVFS_MAKE_ALIAS: 1255 devfs_make_alias_worker((struct devfs_alias *)msg->mdv_load); 1256 break; 1257 case DEVFS_DESTROY_ALIAS: 1258 devfs_destroy_alias_worker((struct devfs_alias *)msg->mdv_load); 1259 break; 1260 case DEVFS_APPLY_RULES: 1261 devfs_apply_reset_rules_caller(msg->mdv_name, 1); 1262 break; 1263 case DEVFS_RESET_RULES: 1264 devfs_apply_reset_rules_caller(msg->mdv_name, 0); 1265 break; 1266 case DEVFS_SCAN_CALLBACK: 1267 devfs_scan_callback_worker((devfs_scan_t *)msg->mdv_load, 1268 msg->mdv_load2); 1269 break; 1270 case DEVFS_CLR_RELATED_FLAG: 1271 devfs_clr_related_flag_worker(msg->mdv_flags.dev, 1272 msg->mdv_flags.flag); 1273 break; 1274 case DEVFS_DESTROY_RELATED_WO_FLAG: 1275 devfs_destroy_related_without_flag_worker(msg->mdv_flags.dev, 1276 msg->mdv_flags.flag); 1277 break; 1278 case DEVFS_INODE_TO_VNODE: 1279 msg->mdv_ino.vp = devfs_iterate_topology( 1280 DEVFS_MNTDATA(msg->mdv_ino.mp)->root_node, 1281 (devfs_iterate_callback_t *)devfs_inode_to_vnode_worker_callback, 1282 &msg->mdv_ino.ino); 1283 break; 1284 case DEVFS_TERMINATE_CORE: 1285 devfs_run = 0; 1286 break; 1287 case DEVFS_SYNC: 1288 break; 1289 default: 1290 devfs_debug(DEVFS_DEBUG_WARNING, 1291 "devfs_msg_core: unknown message " 1292 "received at core\n"); 1293 break; 1294 } 1295 lockmgr(&devfs_lock, LK_RELEASE); 1296 } 1297 1298 static void 1299 devfs_devctl_notify(cdev_t dev, const char *ev) 1300 { 1301 static const char prefix[] = "cdev="; 1302 char *data; 1303 int namelen; 1304 1305 namelen = strlen(dev->si_name); 1306 data = kmalloc(namelen + sizeof(prefix), M_TEMP, M_WAITOK); 1307 memcpy(data, prefix, sizeof(prefix) - 1); 1308 memcpy(data + sizeof(prefix) - 1, dev->si_name, namelen + 1); 1309 devctl_notify("DEVFS", "CDEV", ev, data); 1310 kfree(data, M_TEMP); 1311 } 1312 1313 /* 1314 * Worker function to insert a new dev into the dev list and initialize its 1315 * permissions. It also calls devfs_propagate_dev which in turn propagates 1316 * the change to all mount points. 1317 * 1318 * The passed dev is already referenced. This reference is eaten by this 1319 * function and represents the dev's linkage into devfs_dev_list. 1320 */ 1321 static int 1322 devfs_create_dev_worker(cdev_t dev, uid_t uid, gid_t gid, int perms) 1323 { 1324 KKASSERT(dev); 1325 1326 dev->si_uid = uid; 1327 dev->si_gid = gid; 1328 dev->si_perms = perms; 1329 1330 devfs_link_dev(dev); 1331 devfs_propagate_dev(dev, 1); 1332 1333 udev_event_attach(dev, NULL, 0); 1334 devfs_devctl_notify(dev, "CREATE"); 1335 1336 return 0; 1337 } 1338 1339 /* 1340 * Worker function to delete a dev from the dev list and free the cdev. 1341 * It also calls devfs_propagate_dev which in turn propagates the change 1342 * to all mount points. 1343 */ 1344 static int 1345 devfs_destroy_dev_worker(cdev_t dev) 1346 { 1347 int error; 1348 1349 KKASSERT(dev); 1350 KKASSERT((lockstatus(&devfs_lock, curthread)) == LK_EXCLUSIVE); 1351 1352 error = devfs_unlink_dev(dev); 1353 devfs_propagate_dev(dev, 0); 1354 1355 devfs_devctl_notify(dev, "DESTROY"); 1356 udev_event_detach(dev, NULL, 0); 1357 1358 if (error == 0) 1359 release_dev(dev); /* link ref */ 1360 release_dev(dev); 1361 release_dev(dev); 1362 1363 return 0; 1364 } 1365 1366 /* 1367 * Worker function to destroy all devices with a certain basename. 1368 * Calls devfs_destroy_dev_worker for the actual destruction. 1369 */ 1370 static int 1371 devfs_destroy_related_worker(cdev_t needle) 1372 { 1373 cdev_t dev; 1374 1375 restart: 1376 devfs_debug(DEVFS_DEBUG_DEBUG, "related worker: %s\n", 1377 needle->si_name); 1378 TAILQ_FOREACH(dev, &devfs_dev_list, link) { 1379 if (dev->si_parent == needle) { 1380 devfs_destroy_related_worker(dev); 1381 devfs_destroy_dev_worker(dev); 1382 goto restart; 1383 } 1384 } 1385 return 0; 1386 } 1387 1388 static int 1389 devfs_clr_related_flag_worker(cdev_t needle, uint32_t flag) 1390 { 1391 cdev_t dev, dev1; 1392 1393 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1394 if (dev->si_parent == needle) { 1395 devfs_clr_related_flag_worker(dev, flag); 1396 dev->si_flags &= ~flag; 1397 } 1398 } 1399 1400 return 0; 1401 } 1402 1403 static int 1404 devfs_destroy_related_without_flag_worker(cdev_t needle, uint32_t flag) 1405 { 1406 cdev_t dev; 1407 1408 restart: 1409 devfs_debug(DEVFS_DEBUG_DEBUG, "related_wo_flag: %s\n", 1410 needle->si_name); 1411 1412 TAILQ_FOREACH(dev, &devfs_dev_list, link) { 1413 if (dev->si_parent == needle) { 1414 devfs_destroy_related_without_flag_worker(dev, flag); 1415 if (!(dev->si_flags & flag)) { 1416 devfs_destroy_dev_worker(dev); 1417 devfs_debug(DEVFS_DEBUG_DEBUG, 1418 "related_wo_flag: %s restart\n", dev->si_name); 1419 goto restart; 1420 } 1421 } 1422 } 1423 1424 return 0; 1425 } 1426 1427 /* 1428 * Worker function that creates all device nodes on top of a devfs 1429 * root node. 1430 */ 1431 static int 1432 devfs_create_all_dev_worker(struct devfs_node *root) 1433 { 1434 cdev_t dev; 1435 1436 KKASSERT(root); 1437 1438 TAILQ_FOREACH(dev, &devfs_dev_list, link) { 1439 devfs_create_device_node(root, dev, NULL, NULL, NULL); 1440 } 1441 1442 return 0; 1443 } 1444 1445 /* 1446 * Worker function that destroys all devices that match a specific 1447 * dev_ops and/or minor. If minor is less than 0, it is not matched 1448 * against. It also propagates all changes. 1449 */ 1450 static int 1451 devfs_destroy_dev_by_ops_worker(struct dev_ops *ops, int minor) 1452 { 1453 cdev_t dev, dev1; 1454 1455 KKASSERT(ops); 1456 1457 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1458 if (dev->si_ops != ops) 1459 continue; 1460 if ((minor < 0) || (dev->si_uminor == minor)) { 1461 devfs_destroy_dev_worker(dev); 1462 } 1463 } 1464 1465 return 0; 1466 } 1467 1468 /* 1469 * Worker function that registers a new clone handler in devfs. 1470 */ 1471 static int 1472 devfs_chandler_add_worker(const char *name, d_clone_t *nhandler) 1473 { 1474 struct devfs_clone_handler *chandler = NULL; 1475 u_char len = strlen(name); 1476 1477 if (len == 0) 1478 return 1; 1479 1480 TAILQ_FOREACH(chandler, &devfs_chandler_list, link) { 1481 if (chandler->namlen != len) 1482 continue; 1483 1484 if (!memcmp(chandler->name, name, len)) { 1485 /* Clonable basename already exists */ 1486 return 1; 1487 } 1488 } 1489 1490 chandler = kmalloc(sizeof(*chandler), M_DEVFS, M_WAITOK | M_ZERO); 1491 chandler->name = kstrdup(name, M_DEVFS); 1492 chandler->namlen = len; 1493 chandler->nhandler = nhandler; 1494 1495 TAILQ_INSERT_TAIL(&devfs_chandler_list, chandler, link); 1496 return 0; 1497 } 1498 1499 /* 1500 * Worker function that removes a given clone handler from the 1501 * clone handler list. 1502 */ 1503 static int 1504 devfs_chandler_del_worker(const char *name) 1505 { 1506 struct devfs_clone_handler *chandler, *chandler2; 1507 u_char len = strlen(name); 1508 1509 if (len == 0) 1510 return 1; 1511 1512 TAILQ_FOREACH_MUTABLE(chandler, &devfs_chandler_list, link, chandler2) { 1513 if (chandler->namlen != len) 1514 continue; 1515 if (memcmp(chandler->name, name, len)) 1516 continue; 1517 1518 TAILQ_REMOVE(&devfs_chandler_list, chandler, link); 1519 kfree(chandler->name, M_DEVFS); 1520 kfree(chandler, M_DEVFS); 1521 break; 1522 } 1523 1524 return 0; 1525 } 1526 1527 /* 1528 * Worker function that finds a given device name and changes 1529 * the message received accordingly so that when replied to, 1530 * the answer is returned to the caller. 1531 */ 1532 static int 1533 devfs_find_device_by_name_worker(devfs_msg_t devfs_msg) 1534 { 1535 struct devfs_alias *alias; 1536 cdev_t dev; 1537 cdev_t found = NULL; 1538 1539 TAILQ_FOREACH(dev, &devfs_dev_list, link) { 1540 if (strcmp(devfs_msg->mdv_name, dev->si_name) == 0) { 1541 found = dev; 1542 break; 1543 } 1544 } 1545 if (found == NULL) { 1546 TAILQ_FOREACH(alias, &devfs_alias_list, link) { 1547 if (strcmp(devfs_msg->mdv_name, alias->name) == 0) { 1548 found = alias->dev_target; 1549 break; 1550 } 1551 } 1552 } 1553 devfs_msg->mdv_cdev = found; 1554 1555 return 0; 1556 } 1557 1558 /* 1559 * Worker function that finds a given device udev and changes 1560 * the message received accordingly so that when replied to, 1561 * the answer is returned to the caller. 1562 */ 1563 static int 1564 devfs_find_device_by_udev_worker(devfs_msg_t devfs_msg) 1565 { 1566 cdev_t dev, dev1; 1567 cdev_t found = NULL; 1568 1569 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1570 if (((udev_t)dev->si_inode) == devfs_msg->mdv_udev) { 1571 found = dev; 1572 break; 1573 } 1574 } 1575 devfs_msg->mdv_cdev = found; 1576 1577 return 0; 1578 } 1579 1580 /* 1581 * Worker function that inserts a given alias into the 1582 * alias list, and propagates the alias to all mount 1583 * points. 1584 */ 1585 static int 1586 devfs_make_alias_worker(struct devfs_alias *alias) 1587 { 1588 struct devfs_alias *alias2; 1589 size_t len = strlen(alias->name); 1590 int found = 0; 1591 1592 TAILQ_FOREACH(alias2, &devfs_alias_list, link) { 1593 if (len != alias2->namlen) 1594 continue; 1595 1596 if (!memcmp(alias->name, alias2->name, len)) { 1597 found = 1; 1598 break; 1599 } 1600 } 1601 1602 if (!found) { 1603 /* 1604 * The alias doesn't exist yet, so we add it to the alias list 1605 */ 1606 TAILQ_INSERT_TAIL(&devfs_alias_list, alias, link); 1607 devfs_alias_propagate(alias, 0); 1608 udev_event_attach(alias->dev_target, alias->name, 1); 1609 } else { 1610 devfs_debug(DEVFS_DEBUG_WARNING, 1611 "Warning: duplicate devfs_make_alias for %s\n", 1612 alias->name); 1613 kfree(alias->name, M_DEVFS); 1614 kfree(alias, M_DEVFS); 1615 } 1616 1617 return 0; 1618 } 1619 1620 /* 1621 * Worker function that delete a given alias from the 1622 * alias list, and propagates the removal to all mount 1623 * points. 1624 */ 1625 static int 1626 devfs_destroy_alias_worker(struct devfs_alias *alias) 1627 { 1628 struct devfs_alias *alias2; 1629 int found = 0; 1630 1631 TAILQ_FOREACH(alias2, &devfs_alias_list, link) { 1632 if (alias->dev_target != alias2->dev_target) 1633 continue; 1634 1635 if (devfs_WildCmp(alias->name, alias2->name) == 0) { 1636 found = 1; 1637 break; 1638 } 1639 } 1640 1641 if (!found) { 1642 devfs_debug(DEVFS_DEBUG_WARNING, 1643 "Warning: devfs_destroy_alias for inexistant alias: %s\n", 1644 alias->name); 1645 kfree(alias->name, M_DEVFS); 1646 kfree(alias, M_DEVFS); 1647 } else { 1648 /* 1649 * The alias exists, so we delete it from the alias list 1650 */ 1651 TAILQ_REMOVE(&devfs_alias_list, alias2, link); 1652 devfs_alias_propagate(alias2, 1); 1653 udev_event_detach(alias2->dev_target, alias2->name, 1); 1654 kfree(alias->name, M_DEVFS); 1655 kfree(alias, M_DEVFS); 1656 kfree(alias2->name, M_DEVFS); 1657 kfree(alias2, M_DEVFS); 1658 } 1659 1660 return 0; 1661 } 1662 1663 /* 1664 * Function that removes and frees all aliases. 1665 */ 1666 static int 1667 devfs_alias_reap(void) 1668 { 1669 struct devfs_alias *alias, *alias2; 1670 1671 TAILQ_FOREACH_MUTABLE(alias, &devfs_alias_list, link, alias2) { 1672 TAILQ_REMOVE(&devfs_alias_list, alias, link); 1673 kfree(alias->name, M_DEVFS); 1674 kfree(alias, M_DEVFS); 1675 } 1676 return 0; 1677 } 1678 1679 /* 1680 * Function that removes an alias matching a specific cdev and frees 1681 * it accordingly. 1682 */ 1683 static int 1684 devfs_alias_remove(cdev_t dev) 1685 { 1686 struct devfs_alias *alias, *alias2; 1687 1688 TAILQ_FOREACH_MUTABLE(alias, &devfs_alias_list, link, alias2) { 1689 if (alias->dev_target == dev) { 1690 TAILQ_REMOVE(&devfs_alias_list, alias, link); 1691 udev_event_detach(alias->dev_target, alias->name, 1); 1692 kfree(alias->name, M_DEVFS); 1693 kfree(alias, M_DEVFS); 1694 } 1695 } 1696 return 0; 1697 } 1698 1699 /* 1700 * This function propagates an alias addition or removal to 1701 * all mount points. 1702 */ 1703 static int 1704 devfs_alias_propagate(struct devfs_alias *alias, int remove) 1705 { 1706 struct devfs_mnt_data *mnt; 1707 1708 TAILQ_FOREACH(mnt, &devfs_mnt_list, link) { 1709 if (remove) { 1710 devfs_destroy_node(mnt->root_node, alias->name); 1711 } else { 1712 devfs_alias_apply(mnt->root_node, alias); 1713 } 1714 } 1715 return 0; 1716 } 1717 1718 /* 1719 * This function is a recursive function iterating through 1720 * all device nodes in the topology and, if applicable, 1721 * creating the relevant alias for a device node. 1722 */ 1723 static int 1724 devfs_alias_apply(struct devfs_node *node, struct devfs_alias *alias) 1725 { 1726 struct devfs_node *node1, *node2; 1727 1728 KKASSERT(alias != NULL); 1729 1730 if ((node->node_type == Nroot) || (node->node_type == Ndir)) { 1731 if (node->nchildren > 2) { 1732 TAILQ_FOREACH_MUTABLE(node1, DEVFS_DENODE_HEAD(node), link, node2) { 1733 devfs_alias_apply(node1, alias); 1734 } 1735 } 1736 } else { 1737 if (node->d_dev == alias->dev_target) 1738 devfs_alias_create(alias->name, node, 0); 1739 } 1740 return 0; 1741 } 1742 1743 /* 1744 * This function checks if any alias possibly is applicable 1745 * to the given node. If so, the alias is created. 1746 */ 1747 static int 1748 devfs_alias_check_create(struct devfs_node *node) 1749 { 1750 struct devfs_alias *alias; 1751 1752 TAILQ_FOREACH(alias, &devfs_alias_list, link) { 1753 if (node->d_dev == alias->dev_target) 1754 devfs_alias_create(alias->name, node, 0); 1755 } 1756 return 0; 1757 } 1758 1759 /* 1760 * This function creates an alias with a given name 1761 * linking to a given devfs node. It also increments 1762 * the link count on the target node. 1763 */ 1764 int 1765 devfs_alias_create(char *name_orig, struct devfs_node *target, int rule_based) 1766 { 1767 struct mount *mp = target->mp; 1768 struct devfs_node *parent = DEVFS_MNTDATA(mp)->root_node; 1769 struct devfs_node *linknode; 1770 char *create_path = NULL; 1771 char *name; 1772 char *name_buf; 1773 int result = 0; 1774 1775 KKASSERT((lockstatus(&devfs_lock, curthread)) == LK_EXCLUSIVE); 1776 1777 name_buf = kmalloc(PATH_MAX, M_TEMP, M_WAITOK); 1778 devfs_resolve_name_path(name_orig, name_buf, &create_path, &name); 1779 1780 if (create_path) 1781 parent = devfs_resolve_or_create_path(parent, create_path, 1); 1782 1783 1784 if (devfs_find_device_node_by_name(parent, name)) { 1785 devfs_debug(DEVFS_DEBUG_WARNING, 1786 "Node already exists: %s " 1787 "(devfs_make_alias_worker)!\n", 1788 name); 1789 result = 1; 1790 goto done; 1791 } 1792 1793 linknode = devfs_allocp(Nlink, name, parent, mp, NULL); 1794 if (linknode == NULL) { 1795 result = 1; 1796 goto done; 1797 } 1798 1799 linknode->link_target = target; 1800 target->nlinks++; 1801 1802 if (rule_based) 1803 linknode->flags |= DEVFS_RULE_CREATED; 1804 1805 done: 1806 kfree(name_buf, M_TEMP); 1807 return (result); 1808 } 1809 1810 /* 1811 * This function is called by the core and handles mount point 1812 * strings. It either calls the relevant worker (devfs_apply_ 1813 * reset_rules_worker) on all mountpoints or only a specific 1814 * one. 1815 */ 1816 static int 1817 devfs_apply_reset_rules_caller(char *mountto, int apply) 1818 { 1819 struct devfs_mnt_data *mnt; 1820 1821 if (mountto[0] == '*') { 1822 TAILQ_FOREACH(mnt, &devfs_mnt_list, link) { 1823 devfs_iterate_topology(mnt->root_node, 1824 (apply)?(devfs_rule_check_apply):(devfs_rule_reset_node), 1825 NULL); 1826 } 1827 } else { 1828 TAILQ_FOREACH(mnt, &devfs_mnt_list, link) { 1829 if (!strcmp(mnt->mp->mnt_stat.f_mntonname, mountto)) { 1830 devfs_iterate_topology(mnt->root_node, 1831 (apply)?(devfs_rule_check_apply):(devfs_rule_reset_node), 1832 NULL); 1833 break; 1834 } 1835 } 1836 } 1837 1838 kfree(mountto, M_DEVFS); 1839 return 0; 1840 } 1841 1842 /* 1843 * This function calls a given callback function for 1844 * every dev node in the devfs dev list. 1845 */ 1846 static int 1847 devfs_scan_callback_worker(devfs_scan_t *callback, void *arg) 1848 { 1849 cdev_t dev, dev1; 1850 struct devfs_alias *alias, *alias1; 1851 1852 TAILQ_FOREACH_MUTABLE(dev, &devfs_dev_list, link, dev1) { 1853 callback(dev->si_name, dev, false, arg); 1854 } 1855 TAILQ_FOREACH_MUTABLE(alias, &devfs_alias_list, link, alias1) { 1856 callback(alias->name, alias->dev_target, true, arg); 1857 } 1858 1859 return 0; 1860 } 1861 1862 /* 1863 * This function tries to resolve a given directory, or if not 1864 * found and creation requested, creates the given directory. 1865 */ 1866 static struct devfs_node * 1867 devfs_resolve_or_create_dir(struct devfs_node *parent, char *dir_name, 1868 size_t name_len, int create) 1869 { 1870 struct devfs_node *node, *found = NULL; 1871 1872 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(parent), link) { 1873 if (name_len != node->d_dir.d_namlen) 1874 continue; 1875 1876 if (!memcmp(dir_name, node->d_dir.d_name, name_len)) { 1877 found = node; 1878 break; 1879 } 1880 } 1881 1882 if ((found == NULL) && (create)) { 1883 found = devfs_allocp(Ndir, dir_name, parent, parent->mp, NULL); 1884 } 1885 1886 return found; 1887 } 1888 1889 /* 1890 * This function tries to resolve a complete path. If creation is requested, 1891 * if a given part of the path cannot be resolved (because it doesn't exist), 1892 * it is created. 1893 */ 1894 struct devfs_node * 1895 devfs_resolve_or_create_path(struct devfs_node *parent, char *path, int create) 1896 { 1897 struct devfs_node *node = parent; 1898 char *buf; 1899 size_t idx = 0; 1900 1901 if (path == NULL) 1902 return parent; 1903 1904 buf = kmalloc(PATH_MAX, M_TEMP, M_WAITOK); 1905 1906 while (*path && idx < PATH_MAX - 1) { 1907 if (*path != '/') { 1908 buf[idx++] = *path; 1909 } else { 1910 buf[idx] = '\0'; 1911 node = devfs_resolve_or_create_dir(node, buf, idx, create); 1912 if (node == NULL) { 1913 kfree(buf, M_TEMP); 1914 return NULL; 1915 } 1916 idx = 0; 1917 } 1918 ++path; 1919 } 1920 buf[idx] = '\0'; 1921 node = devfs_resolve_or_create_dir(node, buf, idx, create); 1922 kfree (buf, M_TEMP); 1923 return (node); 1924 } 1925 1926 /* 1927 * Takes a full path and strips it into a directory path and a name. 1928 * For a/b/c/foo, it returns foo in namep and a/b/c in pathp. It 1929 * requires a working buffer with enough size to keep the whole 1930 * fullpath. 1931 */ 1932 int 1933 devfs_resolve_name_path(char *fullpath, char *buf, char **pathp, char **namep) 1934 { 1935 char *name = NULL; 1936 char *path = NULL; 1937 size_t len = strlen(fullpath) + 1; 1938 int i; 1939 1940 KKASSERT((fullpath != NULL) && (buf != NULL)); 1941 KKASSERT((pathp != NULL) && (namep != NULL)); 1942 1943 memcpy(buf, fullpath, len); 1944 1945 for (i = len-1; i>= 0; i--) { 1946 if (buf[i] == '/') { 1947 buf[i] = '\0'; 1948 name = &(buf[i+1]); 1949 path = buf; 1950 break; 1951 } 1952 } 1953 1954 *pathp = path; 1955 1956 if (name) { 1957 *namep = name; 1958 } else { 1959 *namep = buf; 1960 } 1961 1962 return 0; 1963 } 1964 1965 /* 1966 * This function creates a new devfs node for a given device. It can 1967 * handle a complete path as device name, and accordingly creates 1968 * the path and the final device node. 1969 * 1970 * The reference count on the passed dev remains unchanged. 1971 */ 1972 struct devfs_node * 1973 devfs_create_device_node(struct devfs_node *root, cdev_t dev, 1974 int *existsp, char *dev_name, char *path_fmt, ...) 1975 { 1976 struct devfs_node *parent, *node = NULL; 1977 char *path = NULL; 1978 char *name; 1979 char *name_buf; 1980 __va_list ap; 1981 int i, found; 1982 char *create_path = NULL; 1983 char *names = "pqrsPQRS"; 1984 1985 name_buf = kmalloc(PATH_MAX, M_TEMP, M_WAITOK); 1986 1987 if (existsp) 1988 *existsp = 0; 1989 1990 if (path_fmt != NULL) { 1991 __va_start(ap, path_fmt); 1992 kvasnrprintf(&path, PATH_MAX, 10, path_fmt, ap); 1993 __va_end(ap); 1994 } 1995 1996 parent = devfs_resolve_or_create_path(root, path, 1); 1997 KKASSERT(parent); 1998 1999 devfs_resolve_name_path( 2000 ((dev_name == NULL) && (dev))?(dev->si_name):(dev_name), 2001 name_buf, &create_path, &name); 2002 2003 if (create_path) 2004 parent = devfs_resolve_or_create_path(parent, create_path, 1); 2005 2006 2007 node = devfs_find_device_node_by_name(parent, name); 2008 if (node) { 2009 if (node->d_dev == dev) { 2010 /* 2011 * Allow case where device caches dev after the 2012 * close and might desire to reuse it. 2013 */ 2014 if (existsp) 2015 *existsp = 1; 2016 } else { 2017 devfs_debug(DEVFS_DEBUG_WARNING, 2018 "devfs_create_device_node: " 2019 "DEVICE %s ALREADY EXISTS!!! " 2020 "Ignoring creation request.\n", 2021 name); 2022 node = NULL; 2023 } 2024 goto out; 2025 } 2026 2027 node = devfs_allocp(Ndev, name, parent, parent->mp, dev); 2028 nanotime(&parent->mtime); 2029 2030 /* 2031 * Ugly unix98 pty magic, to hide pty master (ptm) devices and their 2032 * directory 2033 */ 2034 if ((dev) && (strlen(dev->si_name) >= 4) && 2035 (!memcmp(dev->si_name, "ptm/", 4))) { 2036 node->parent->flags |= DEVFS_HIDDEN; 2037 node->flags |= DEVFS_HIDDEN; 2038 } 2039 2040 /* 2041 * Ugly pty magic, to tag pty devices as such and hide them if needed. 2042 */ 2043 if ((strlen(name) >= 3) && (!memcmp(name, "pty", 3))) 2044 node->flags |= (DEVFS_PTY | DEVFS_INVISIBLE); 2045 2046 if ((strlen(name) >= 3) && (!memcmp(name, "tty", 3))) { 2047 found = 0; 2048 for (i = 0; i < strlen(names); i++) { 2049 if (name[3] == names[i]) { 2050 found = 1; 2051 break; 2052 } 2053 } 2054 if (found) 2055 node->flags |= (DEVFS_PTY | DEVFS_INVISIBLE); 2056 } 2057 2058 out: 2059 kfree(name_buf, M_TEMP); 2060 kvasfree(&path); 2061 return node; 2062 } 2063 2064 /* 2065 * This function finds a given device node in the topology with a given 2066 * cdev. 2067 */ 2068 void * 2069 devfs_find_device_node_callback(struct devfs_node *node, cdev_t target) 2070 { 2071 if ((node->node_type == Ndev) && (node->d_dev == target)) { 2072 return node; 2073 } 2074 2075 return NULL; 2076 } 2077 2078 /* 2079 * This function finds a device node in the given parent directory by its 2080 * name and returns it. 2081 */ 2082 struct devfs_node * 2083 devfs_find_device_node_by_name(struct devfs_node *parent, char *target) 2084 { 2085 struct devfs_node *node, *found = NULL; 2086 size_t len = strlen(target); 2087 2088 TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(parent), link) { 2089 if (len != node->d_dir.d_namlen) 2090 continue; 2091 2092 if (!memcmp(node->d_dir.d_name, target, len)) { 2093 found = node; 2094 break; 2095 } 2096 } 2097 2098 return found; 2099 } 2100 2101 static void * 2102 devfs_inode_to_vnode_worker_callback(struct devfs_node *node, ino_t *inop) 2103 { 2104 struct vnode *vp = NULL; 2105 ino_t target = *inop; 2106 2107 if (node->d_dir.d_ino == target) { 2108 if (node->v_node) { 2109 vp = node->v_node; 2110 vget(vp, LK_EXCLUSIVE | LK_RETRY); 2111 vn_unlock(vp); 2112 } else { 2113 devfs_allocv(&vp, node); 2114 vn_unlock(vp); 2115 } 2116 } 2117 2118 return vp; 2119 } 2120 2121 /* 2122 * This function takes a cdev and removes its devfs node in the 2123 * given topology. The cdev remains intact. 2124 */ 2125 int 2126 devfs_destroy_device_node(struct devfs_node *root, cdev_t target) 2127 { 2128 KKASSERT(target != NULL); 2129 return devfs_destroy_node(root, target->si_name); 2130 } 2131 2132 /* 2133 * This function takes a path to a devfs node, resolves it and 2134 * removes the devfs node from the given topology. 2135 */ 2136 int 2137 devfs_destroy_node(struct devfs_node *root, char *target) 2138 { 2139 struct devfs_node *node, *parent; 2140 char *name; 2141 char *name_buf; 2142 char *create_path = NULL; 2143 2144 KKASSERT(target); 2145 2146 name_buf = kmalloc(PATH_MAX, M_TEMP, M_WAITOK); 2147 ksnprintf(name_buf, PATH_MAX, "%s", target); 2148 2149 devfs_resolve_name_path(target, name_buf, &create_path, &name); 2150 2151 if (create_path) 2152 parent = devfs_resolve_or_create_path(root, create_path, 0); 2153 else 2154 parent = root; 2155 2156 if (parent == NULL) { 2157 kfree(name_buf, M_TEMP); 2158 return 1; 2159 } 2160 2161 node = devfs_find_device_node_by_name(parent, name); 2162 2163 if (node) { 2164 nanotime(&node->parent->mtime); 2165 devfs_gc(node); 2166 } 2167 2168 kfree(name_buf, M_TEMP); 2169 2170 return 0; 2171 } 2172 2173 /* 2174 * Just set perms and ownership for given node. 2175 */ 2176 int 2177 devfs_set_perms(struct devfs_node *node, uid_t uid, gid_t gid, 2178 u_short mode, u_long flags) 2179 { 2180 node->mode = mode; 2181 node->uid = uid; 2182 node->gid = gid; 2183 2184 return 0; 2185 } 2186 2187 /* 2188 * Propagates a device attach/detach to all mount 2189 * points. Also takes care of automatic alias removal 2190 * for a deleted cdev. 2191 */ 2192 static int 2193 devfs_propagate_dev(cdev_t dev, int attach) 2194 { 2195 struct devfs_mnt_data *mnt; 2196 2197 TAILQ_FOREACH(mnt, &devfs_mnt_list, link) { 2198 if (attach) { 2199 /* Device is being attached */ 2200 devfs_create_device_node(mnt->root_node, dev, 2201 NULL, NULL, NULL); 2202 } else { 2203 /* Device is being detached */ 2204 devfs_alias_remove(dev); 2205 devfs_destroy_device_node(mnt->root_node, dev); 2206 } 2207 } 2208 return 0; 2209 } 2210 2211 /* 2212 * devfs_clone either returns a basename from a complete name by 2213 * returning the length of the name without trailing digits, or, 2214 * if clone != 0, calls the device's clone handler to get a new 2215 * device, which in turn is returned in devp. 2216 * 2217 * Caller must hold a shared devfs_lock 2218 */ 2219 cdev_t 2220 devfs_clone(cdev_t dev, const char *name, size_t len, int mode, 2221 struct ucred *cred) 2222 { 2223 int error; 2224 struct devfs_clone_handler *chandler; 2225 struct dev_clone_args ap; 2226 2227 TAILQ_FOREACH(chandler, &devfs_chandler_list, link) { 2228 if (chandler->namlen != len) 2229 continue; 2230 if ((!memcmp(chandler->name, name, len)) && 2231 (chandler->nhandler)) { 2232 /* 2233 * We have to unlock across the config and the 2234 * callback to avoid deadlocking. The device is 2235 * likely to obtain its own lock in the callback 2236 * and might then call into devfs. 2237 */ 2238 lockmgr(&devfs_lock, LK_RELEASE); 2239 devfs_config(); 2240 ap.a_head.a_dev = dev; 2241 ap.a_dev = NULL; 2242 ap.a_name = name; 2243 ap.a_namelen = len; 2244 ap.a_mode = mode; 2245 ap.a_cred = cred; 2246 error = (chandler->nhandler)(&ap); 2247 lockmgr(&devfs_lock, LK_SHARED); 2248 if (error) 2249 continue; 2250 2251 return ap.a_dev; 2252 } 2253 } 2254 2255 return NULL; 2256 } 2257 2258 2259 /* 2260 * Registers a new orphan in the orphan list. 2261 */ 2262 void 2263 devfs_tracer_add_orphan(struct devfs_node *node) 2264 { 2265 struct devfs_orphan *orphan; 2266 2267 KKASSERT(node); 2268 orphan = kmalloc(sizeof(struct devfs_orphan), M_DEVFS, M_WAITOK); 2269 orphan->node = node; 2270 2271 KKASSERT((node->flags & DEVFS_ORPHANED) == 0); 2272 node->flags |= DEVFS_ORPHANED; 2273 TAILQ_INSERT_TAIL(DEVFS_ORPHANLIST(node->mp), orphan, link); 2274 } 2275 2276 /* 2277 * Removes an orphan from the orphan list. 2278 */ 2279 void 2280 devfs_tracer_del_orphan(struct devfs_node *node) 2281 { 2282 struct devfs_orphan *orphan; 2283 2284 KKASSERT(node); 2285 2286 TAILQ_FOREACH(orphan, DEVFS_ORPHANLIST(node->mp), link) { 2287 if (orphan->node == node) { 2288 node->flags &= ~DEVFS_ORPHANED; 2289 TAILQ_REMOVE(DEVFS_ORPHANLIST(node->mp), orphan, link); 2290 kfree(orphan, M_DEVFS); 2291 break; 2292 } 2293 } 2294 } 2295 2296 /* 2297 * Counts the orphans in the orphan list, and if cleanup 2298 * is specified, also frees the orphan and removes it from 2299 * the list. 2300 */ 2301 size_t 2302 devfs_tracer_orphan_count(struct mount *mp, int cleanup) 2303 { 2304 struct devfs_orphan *orphan, *orphan2; 2305 size_t count = 0; 2306 2307 TAILQ_FOREACH_MUTABLE(orphan, DEVFS_ORPHANLIST(mp), link, orphan2) { 2308 count++; 2309 /* 2310 * If we are instructed to clean up, we do so. 2311 */ 2312 if (cleanup) { 2313 TAILQ_REMOVE(DEVFS_ORPHANLIST(mp), orphan, link); 2314 orphan->node->flags &= ~DEVFS_ORPHANED; 2315 devfs_freep(orphan->node); 2316 kfree(orphan, M_DEVFS); 2317 } 2318 } 2319 2320 return count; 2321 } 2322 2323 /* 2324 * Fetch an ino_t from the global d_ino by increasing it 2325 * while spinlocked. 2326 */ 2327 static ino_t 2328 devfs_fetch_ino(void) 2329 { 2330 ino_t ret; 2331 2332 spin_lock(&ino_lock); 2333 ret = d_ino++; 2334 spin_unlock(&ino_lock); 2335 2336 return ret; 2337 } 2338 2339 /* 2340 * Allocates a new cdev and initializes it's most basic 2341 * fields. 2342 */ 2343 cdev_t 2344 devfs_new_cdev(struct dev_ops *ops, int minor, struct dev_ops *bops) 2345 { 2346 cdev_t dev = sysref_alloc(&cdev_sysref_class); 2347 2348 sysref_activate(&dev->si_sysref); 2349 reference_dev(dev); 2350 bzero(dev, offsetof(struct cdev, si_sysref)); 2351 2352 dev->si_uid = 0; 2353 dev->si_gid = 0; 2354 dev->si_perms = 0; 2355 dev->si_drv1 = NULL; 2356 dev->si_drv2 = NULL; 2357 dev->si_lastread = 0; /* time_uptime */ 2358 dev->si_lastwrite = 0; /* time_uptime */ 2359 2360 dev->si_dict = NULL; 2361 dev->si_parent = NULL; 2362 dev->si_ops = ops; 2363 dev->si_flags = 0; 2364 dev->si_uminor = minor; 2365 dev->si_bops = bops; 2366 2367 /* 2368 * Since the disk subsystem is in the way, we need to 2369 * propagate the D_CANFREE from bops (and ops) to 2370 * si_flags. 2371 */ 2372 if (bops && (bops->head.flags & D_CANFREE)) { 2373 dev->si_flags |= SI_CANFREE; 2374 } else if (ops->head.flags & D_CANFREE) { 2375 dev->si_flags |= SI_CANFREE; 2376 } 2377 2378 /* If there is a backing device, we reference its ops */ 2379 dev->si_inode = makeudev( 2380 devfs_reference_ops((bops)?(bops):(ops)), 2381 minor ); 2382 dev->si_umajor = umajor(dev->si_inode); 2383 2384 return dev; 2385 } 2386 2387 static void 2388 devfs_cdev_terminate(cdev_t dev) 2389 { 2390 int locked = 0; 2391 2392 /* Check if it is locked already. if not, we acquire the devfs lock */ 2393 if ((lockstatus(&devfs_lock, curthread)) != LK_EXCLUSIVE) { 2394 lockmgr(&devfs_lock, LK_EXCLUSIVE); 2395 locked = 1; 2396 } 2397 2398 /* 2399 * Make sure the node isn't linked anymore. Otherwise we've screwed 2400 * up somewhere, since normal devs are unlinked on the call to 2401 * destroy_dev and only-cdevs that have not been used for cloning 2402 * are not linked in the first place. only-cdevs used for cloning 2403 * will be linked in, too, and should only be destroyed via 2404 * destroy_dev, not destroy_only_dev, so we catch that problem, too. 2405 */ 2406 KKASSERT((dev->si_flags & SI_DEVFS_LINKED) == 0); 2407 2408 /* If we acquired the lock, we also get rid of it */ 2409 if (locked) 2410 lockmgr(&devfs_lock, LK_RELEASE); 2411 2412 /* If there is a backing device, we release the backing device's ops */ 2413 devfs_release_ops((dev->si_bops)?(dev->si_bops):(dev->si_ops)); 2414 2415 /* Finally destroy the device */ 2416 sysref_put(&dev->si_sysref); 2417 } 2418 2419 /* 2420 * Dummies for now (individual locks for MPSAFE) 2421 */ 2422 static void 2423 devfs_cdev_lock(cdev_t dev) 2424 { 2425 } 2426 2427 static void 2428 devfs_cdev_unlock(cdev_t dev) 2429 { 2430 } 2431 2432 static int 2433 devfs_detached_filter_eof(struct knote *kn, long hint) 2434 { 2435 kn->kn_flags |= (EV_EOF | EV_NODATA); 2436 return (1); 2437 } 2438 2439 static void 2440 devfs_detached_filter_detach(struct knote *kn) 2441 { 2442 cdev_t dev = (cdev_t)kn->kn_hook; 2443 2444 knote_remove(&dev->si_kqinfo.ki_note, kn); 2445 } 2446 2447 static struct filterops devfs_detached_filterops = 2448 { FILTEROP_ISFD, NULL, 2449 devfs_detached_filter_detach, 2450 devfs_detached_filter_eof }; 2451 2452 /* 2453 * Delegates knote filter handling responsibility to devfs 2454 * 2455 * Any device that implements kqfilter event handling and could be detached 2456 * or shut down out from under the kevent subsystem must allow devfs to 2457 * assume responsibility for any knotes it may hold. 2458 */ 2459 void 2460 devfs_assume_knotes(cdev_t dev, struct kqinfo *kqi) 2461 { 2462 /* 2463 * Let kern/kern_event.c do the heavy lifting. 2464 */ 2465 knote_assume_knotes(kqi, &dev->si_kqinfo, 2466 &devfs_detached_filterops, (void *)dev); 2467 2468 /* 2469 * These should probably be activated individually, but doing so 2470 * would require refactoring kq's public in-kernel interface. 2471 */ 2472 KNOTE(&dev->si_kqinfo.ki_note, 0); 2473 } 2474 2475 /* 2476 * Links a given cdev into the dev list. 2477 */ 2478 int 2479 devfs_link_dev(cdev_t dev) 2480 { 2481 KKASSERT((dev->si_flags & SI_DEVFS_LINKED) == 0); 2482 dev->si_flags |= SI_DEVFS_LINKED; 2483 TAILQ_INSERT_TAIL(&devfs_dev_list, dev, link); 2484 2485 return 0; 2486 } 2487 2488 /* 2489 * Removes a given cdev from the dev list. The caller is responsible for 2490 * releasing the reference on the device associated with the linkage. 2491 * 2492 * Returns EALREADY if the dev has already been unlinked. 2493 */ 2494 static int 2495 devfs_unlink_dev(cdev_t dev) 2496 { 2497 if ((dev->si_flags & SI_DEVFS_LINKED)) { 2498 TAILQ_REMOVE(&devfs_dev_list, dev, link); 2499 dev->si_flags &= ~SI_DEVFS_LINKED; 2500 return (0); 2501 } 2502 return (EALREADY); 2503 } 2504 2505 int 2506 devfs_node_is_accessible(struct devfs_node *node) 2507 { 2508 if ((node) && (!(node->flags & DEVFS_HIDDEN))) 2509 return 1; 2510 else 2511 return 0; 2512 } 2513 2514 int 2515 devfs_reference_ops(struct dev_ops *ops) 2516 { 2517 int unit; 2518 struct devfs_dev_ops *found = NULL; 2519 struct devfs_dev_ops *devops; 2520 2521 TAILQ_FOREACH(devops, &devfs_dev_ops_list, link) { 2522 if (devops->ops == ops) { 2523 found = devops; 2524 break; 2525 } 2526 } 2527 2528 if (!found) { 2529 found = kmalloc(sizeof(struct devfs_dev_ops), M_DEVFS, M_WAITOK); 2530 found->ops = ops; 2531 found->ref_count = 0; 2532 TAILQ_INSERT_TAIL(&devfs_dev_ops_list, found, link); 2533 } 2534 2535 KKASSERT(found); 2536 2537 if (found->ref_count == 0) { 2538 found->id = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(ops_id), 255); 2539 if (found->id == -1) { 2540 /* Ran out of unique ids */ 2541 devfs_debug(DEVFS_DEBUG_WARNING, 2542 "devfs_reference_ops: WARNING: ran out of unique ids\n"); 2543 } 2544 } 2545 unit = found->id; 2546 ++found->ref_count; 2547 2548 return unit; 2549 } 2550 2551 void 2552 devfs_release_ops(struct dev_ops *ops) 2553 { 2554 struct devfs_dev_ops *found = NULL; 2555 struct devfs_dev_ops *devops; 2556 2557 TAILQ_FOREACH(devops, &devfs_dev_ops_list, link) { 2558 if (devops->ops == ops) { 2559 found = devops; 2560 break; 2561 } 2562 } 2563 2564 KKASSERT(found); 2565 2566 --found->ref_count; 2567 2568 if (found->ref_count == 0) { 2569 TAILQ_REMOVE(&devfs_dev_ops_list, found, link); 2570 devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(ops_id), found->id); 2571 kfree(found, M_DEVFS); 2572 } 2573 } 2574 2575 /* 2576 * Wait for asynchronous messages to complete in the devfs helper 2577 * thread, then return. Do nothing if the helper thread is dead 2578 * or we are being indirectly called from the helper thread itself. 2579 */ 2580 void 2581 devfs_config(void) 2582 { 2583 devfs_msg_t msg; 2584 2585 if (devfs_run && curthread != td_core) { 2586 msg = devfs_msg_get(); 2587 devfs_msg_send_sync(DEVFS_SYNC, msg); 2588 devfs_msg_put(msg); 2589 } 2590 } 2591 2592 /* 2593 * Called on init of devfs; creates the objcaches and 2594 * spawns off the devfs core thread. Also initializes 2595 * locks. 2596 */ 2597 static void 2598 devfs_init(void) 2599 { 2600 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_init() called\n"); 2601 /* Create objcaches for nodes, msgs and devs */ 2602 devfs_node_cache = objcache_create("devfs-node-cache", 0, 0, 2603 NULL, NULL, NULL, 2604 objcache_malloc_alloc, 2605 objcache_malloc_free, 2606 &devfs_node_malloc_args ); 2607 2608 devfs_msg_cache = objcache_create("devfs-msg-cache", 0, 0, 2609 NULL, NULL, NULL, 2610 objcache_malloc_alloc, 2611 objcache_malloc_free, 2612 &devfs_msg_malloc_args ); 2613 2614 devfs_dev_cache = objcache_create("devfs-dev-cache", 0, 0, 2615 NULL, NULL, NULL, 2616 objcache_malloc_alloc, 2617 objcache_malloc_free, 2618 &devfs_dev_malloc_args ); 2619 2620 devfs_clone_bitmap_init(&DEVFS_CLONE_BITMAP(ops_id)); 2621 2622 /* Initialize the reply-only port which acts as a message drain */ 2623 lwkt_initport_replyonly(&devfs_dispose_port, devfs_msg_autofree_reply); 2624 2625 /* Initialize *THE* devfs lock */ 2626 lockinit(&devfs_lock, "devfs_core lock", 0, 0); 2627 lwkt_token_init(&devfs_token, "devfs_core"); 2628 2629 lockmgr(&devfs_lock, LK_EXCLUSIVE); 2630 lwkt_create(devfs_msg_core, /*args*/NULL, &td_core, NULL, 2631 0, -1, "devfs_msg_core"); 2632 while (devfs_run == 0) 2633 lksleep(td_core, &devfs_lock, 0, "devfsc", 0); 2634 lockmgr(&devfs_lock, LK_RELEASE); 2635 2636 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_init finished\n"); 2637 } 2638 2639 /* 2640 * Called on unload of devfs; takes care of destroying the core 2641 * and the objcaches. Also removes aliases that are no longer needed. 2642 */ 2643 static void 2644 devfs_uninit(void) 2645 { 2646 devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_uninit() called\n"); 2647 2648 devfs_msg_send(DEVFS_TERMINATE_CORE, NULL); 2649 while (devfs_run) 2650 tsleep(td_core, 0, "devfsc", hz*10); 2651 tsleep(td_core, 0, "devfsc", hz); 2652 2653 devfs_clone_bitmap_uninit(&DEVFS_CLONE_BITMAP(ops_id)); 2654 2655 /* Destroy the objcaches */ 2656 objcache_destroy(devfs_msg_cache); 2657 objcache_destroy(devfs_node_cache); 2658 objcache_destroy(devfs_dev_cache); 2659 2660 devfs_alias_reap(); 2661 } 2662 2663 /* 2664 * This is a sysctl handler to assist userland devname(3) to 2665 * find the device name for a given udev. 2666 */ 2667 static int 2668 devfs_sysctl_devname_helper(SYSCTL_HANDLER_ARGS) 2669 { 2670 udev_t udev; 2671 cdev_t found; 2672 int error; 2673 2674 if ((error = SYSCTL_IN(req, &udev, sizeof(udev_t)))) 2675 return (error); 2676 2677 devfs_debug(DEVFS_DEBUG_DEBUG, 2678 "devfs sysctl, received udev: %d\n", udev); 2679 2680 if (udev == NOUDEV) 2681 return(EINVAL); 2682 2683 if ((found = devfs_find_device_by_udev(udev)) == NULL) 2684 return(ENOENT); 2685 2686 return(SYSCTL_OUT(req, found->si_name, strlen(found->si_name) + 1)); 2687 } 2688 2689 2690 SYSCTL_PROC(_kern, OID_AUTO, devname, 2691 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_ANYBODY | CTLFLAG_NOLOCK, 2692 NULL, 0, devfs_sysctl_devname_helper, "", 2693 "helper for devname(3)"); 2694 2695 SYSCTL_NODE(_vfs, OID_AUTO, devfs, CTLFLAG_RW, 0, "devfs"); 2696 TUNABLE_INT("vfs.devfs.debug", &devfs_debug_enable); 2697 SYSCTL_INT(_vfs_devfs, OID_AUTO, debug, CTLFLAG_RW, &devfs_debug_enable, 2698 0, "Enable DevFS debugging"); 2699 2700 SYSINIT(vfs_devfs_register, SI_SUB_DEVFS_CORE, SI_ORDER_FIRST, 2701 devfs_init, NULL); 2702 SYSUNINIT(vfs_devfs_register, SI_SUB_DEVFS_CORE, SI_ORDER_ANY, 2703 devfs_uninit, NULL); 2704 2705 /* 2706 * WildCmp() - compare wild string to sane string 2707 * 2708 * Returns 0 on success, -1 on failure. 2709 */ 2710 static int 2711 wildCmp(const char **mary, int d, const char *w, const char *s) 2712 { 2713 int i; 2714 2715 /* 2716 * skip fixed portion 2717 */ 2718 for (;;) { 2719 switch(*w) { 2720 case '*': 2721 /* 2722 * optimize terminator 2723 */ 2724 if (w[1] == 0) 2725 return(0); 2726 if (w[1] != '?' && w[1] != '*') { 2727 /* 2728 * optimize * followed by non-wild 2729 */ 2730 for (i = 0; s + i < mary[d]; ++i) { 2731 if (s[i] == w[1] && wildCmp(mary, d + 1, w + 1, s + i) == 0) 2732 return(0); 2733 } 2734 } else { 2735 /* 2736 * less-optimal 2737 */ 2738 for (i = 0; s + i < mary[d]; ++i) { 2739 if (wildCmp(mary, d + 1, w + 1, s + i) == 0) 2740 return(0); 2741 } 2742 } 2743 mary[d] = s; 2744 return(-1); 2745 case '?': 2746 if (*s == 0) 2747 return(-1); 2748 ++w; 2749 ++s; 2750 break; 2751 default: 2752 if (*w != *s) 2753 return(-1); 2754 if (*w == 0) /* terminator */ 2755 return(0); 2756 ++w; 2757 ++s; 2758 break; 2759 } 2760 } 2761 /* not reached */ 2762 return(-1); 2763 } 2764 2765 2766 /* 2767 * WildCaseCmp() - compare wild string to sane string, case insensitive 2768 * 2769 * Returns 0 on success, -1 on failure. 2770 */ 2771 static int 2772 wildCaseCmp(const char **mary, int d, const char *w, const char *s) 2773 { 2774 int i; 2775 2776 /* 2777 * skip fixed portion 2778 */ 2779 for (;;) { 2780 switch(*w) { 2781 case '*': 2782 /* 2783 * optimize terminator 2784 */ 2785 if (w[1] == 0) 2786 return(0); 2787 if (w[1] != '?' && w[1] != '*') { 2788 /* 2789 * optimize * followed by non-wild 2790 */ 2791 for (i = 0; s + i < mary[d]; ++i) { 2792 if (s[i] == w[1] && wildCaseCmp(mary, d + 1, w + 1, s + i) == 0) 2793 return(0); 2794 } 2795 } else { 2796 /* 2797 * less-optimal 2798 */ 2799 for (i = 0; s + i < mary[d]; ++i) { 2800 if (wildCaseCmp(mary, d + 1, w + 1, s + i) == 0) 2801 return(0); 2802 } 2803 } 2804 mary[d] = s; 2805 return(-1); 2806 case '?': 2807 if (*s == 0) 2808 return(-1); 2809 ++w; 2810 ++s; 2811 break; 2812 default: 2813 if (*w != *s) { 2814 #define tolower(x) ((x >= 'A' && x <= 'Z')?(x+('a'-'A')):(x)) 2815 if (tolower(*w) != tolower(*s)) 2816 return(-1); 2817 } 2818 if (*w == 0) /* terminator */ 2819 return(0); 2820 ++w; 2821 ++s; 2822 break; 2823 } 2824 } 2825 /* not reached */ 2826 return(-1); 2827 } 2828 2829 struct cdev_privdata { 2830 void *cdpd_data; 2831 cdevpriv_dtr_t cdpd_dtr; 2832 }; 2833 2834 int 2835 devfs_get_cdevpriv(struct file *fp, void **datap) 2836 { 2837 int error; 2838 2839 if (fp == NULL) 2840 return(EBADF); 2841 2842 spin_lock_shared(&fp->f_spin); 2843 if (fp->f_data1 == NULL) { 2844 *datap = NULL; 2845 error = ENOENT; 2846 } else { 2847 struct cdev_privdata *p = fp->f_data1; 2848 2849 *datap = p->cdpd_data; 2850 error = 0; 2851 } 2852 spin_unlock_shared(&fp->f_spin); 2853 2854 return (error); 2855 } 2856 2857 int 2858 devfs_set_cdevpriv(struct file *fp, void *priv, cdevpriv_dtr_t dtr) 2859 { 2860 struct cdev_privdata *p; 2861 int error; 2862 2863 if (fp == NULL) 2864 return (ENOENT); 2865 2866 p = kmalloc(sizeof(struct cdev_privdata), M_DEVFS, M_WAITOK); 2867 p->cdpd_data = priv; 2868 p->cdpd_dtr = dtr; 2869 2870 spin_lock(&fp->f_spin); 2871 if (fp->f_data1 == NULL) { 2872 fp->f_data1 = p; 2873 error = 0; 2874 } else { 2875 error = EBUSY; 2876 } 2877 spin_unlock(&fp->f_spin); 2878 2879 if (error) 2880 kfree(p, M_DEVFS); 2881 2882 return error; 2883 } 2884 2885 void 2886 devfs_clear_cdevpriv(struct file *fp) 2887 { 2888 struct cdev_privdata *p; 2889 2890 if (fp == NULL) 2891 return; 2892 2893 spin_lock(&fp->f_spin); 2894 p = fp->f_data1; 2895 fp->f_data1 = NULL; 2896 spin_unlock(&fp->f_spin); 2897 2898 if (p != NULL) { 2899 p->cdpd_dtr(p->cdpd_data); 2900 kfree(p, M_DEVFS); 2901 } 2902 } 2903 2904 int 2905 devfs_WildCmp(const char *w, const char *s) 2906 { 2907 int i; 2908 int c; 2909 int slen = strlen(s); 2910 const char **mary; 2911 2912 for (i = c = 0; w[i]; ++i) { 2913 if (w[i] == '*') 2914 ++c; 2915 } 2916 mary = kmalloc(sizeof(char *) * (c + 1), M_DEVFS, M_WAITOK); 2917 for (i = 0; i < c; ++i) 2918 mary[i] = s + slen; 2919 i = wildCmp(mary, 0, w, s); 2920 kfree(mary, M_DEVFS); 2921 return(i); 2922 } 2923 2924 int 2925 devfs_WildCaseCmp(const char *w, const char *s) 2926 { 2927 int i; 2928 int c; 2929 int slen = strlen(s); 2930 const char **mary; 2931 2932 for (i = c = 0; w[i]; ++i) { 2933 if (w[i] == '*') 2934 ++c; 2935 } 2936 mary = kmalloc(sizeof(char *) * (c + 1), M_DEVFS, M_WAITOK); 2937 for (i = 0; i < c; ++i) 2938 mary[i] = s + slen; 2939 i = wildCaseCmp(mary, 0, w, s); 2940 kfree(mary, M_DEVFS); 2941 return(i); 2942 } 2943 2944