sys/kern/kern_udev.c

   1 /*
   2  * Copyright (c) 2010,2018 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/uio.h>
  37 #include <sys/kernel.h>
  38 #include <sys/proc.h>
  39 #include <sys/buf.h>
  40 #include <sys/conf.h>
  41 #include <sys/event.h>
  42 #include <sys/vnode.h>
  43 #include <sys/malloc.h>
  44 #include <sys/objcache.h>
  45 #include <sys/ctype.h>
  46 #include <sys/syslog.h>
  47 #include <sys/udev.h>
  48 #include <sys/devfs.h>
  49 #include <libprop/proplib.h>
  50
  51 MALLOC_DEFINE(M_UDEV, "udev", "udev allocs");
  52 static struct objcache *udev_event_kernel_cache;
  53
  54 /* XXX: use UUIDs for identification; would need help from devfs */
  55
  56 static cdev_t           udev_dev;
  57 static d_open_t         udev_dev_open;
  58 static d_close_t        udev_dev_close;
  59 static d_read_t         udev_dev_read;
  60 static d_kqfilter_t     udev_dev_kqfilter;
  61 static d_ioctl_t        udev_dev_ioctl;
  62 static d_clone_t        udev_dev_clone;
  63
  64 struct udev_prop_ctx {
  65         prop_array_t cdevs;
  66         int error;
  67 };
  68
  69 struct udev_event_kernel {
  70         struct udev_event ev;
  71         TAILQ_ENTRY(udev_event_kernel)  link;
  72 };
  73
  74 struct udev_softc {
  75         TAILQ_ENTRY(udev_softc) entry;
  76         int opened;
  77         int initiated;
  78         int unit;
  79         cdev_t dev;
  80
  81         struct udev_event_kernel marker;        /* udev_evq marker */
  82 };
  83
  84 struct cmd_function {
  85         const char *cmd;
  86         int  (*fn)(struct udev_softc *, struct plistref *,
  87                    u_long, prop_dictionary_t);
  88 };
  89
  90 static int _udev_dict_set_cstr(prop_dictionary_t, const char *, char *);
  91 static int _udev_dict_set_int(prop_dictionary_t, const char *, int64_t);
  92 static int _udev_dict_set_uint(prop_dictionary_t, const char *, uint64_t);
  93 static int _udev_dict_delete_key(prop_dictionary_t, const char *);
  94 static prop_dictionary_t udev_init_dict_event(cdev_t, const char *);
  95 static int udev_init_dict(cdev_t);
  96 static int udev_destroy_dict(cdev_t);
  97 static void udev_event_insert(int, prop_dictionary_t);
  98 static void udev_clean_events_locked(void);
  99 static char *udev_event_externalize(struct udev_event_kernel *);
 100 static void udev_getdevs_scan_callback(char *, cdev_t, bool, void *);
 101 static int udev_getdevs_ioctl(struct udev_softc *, struct plistref *,
 102                                         u_long, prop_dictionary_t);
 103 static void udev_dev_filter_detach(struct knote *);
 104 static int udev_dev_filter_read(struct knote *, long);
 105
 106 static struct dev_ops udev_dev_ops = {
 107         { "udev", 0, 0 },
 108         .d_open = udev_dev_open,
 109         .d_close = udev_dev_close,
 110         .d_read = udev_dev_read,
 111         .d_kqfilter = udev_dev_kqfilter,
 112         .d_ioctl = udev_dev_ioctl
 113 };
 114
 115 static struct cmd_function cmd_fn[] = {
 116                 { .cmd = "getdevs", .fn = udev_getdevs_ioctl},
 117                 {NULL, NULL}
 118 };
 119
 120 DEVFS_DEFINE_CLONE_BITMAP(udev);
 121
 122 static TAILQ_HEAD(, udev_softc) udevq;
 123 static TAILQ_HEAD(, udev_event_kernel) udev_evq;
 124 static struct kqinfo udev_kq;
 125 static struct lock udev_lk;
 126 static int udev_evqlen;
 127 static int udev_initiated_count;
 128 static int udev_open_count;
 129 static int udev_seqwait;
 130 static int udev_seq;
 131 static struct lock udev_dict_lk = LOCK_INITIALIZER("dict", 0, 0);
 132
 133 /*
 134  * Acquire the device's si_dict and lock the device's si_dict field.
 135  * If the device does not have an attached dictionary, NULL is returned.
 136  *
 137  * This function must be matched by a udev_put_dict() call regardless of
 138  * the return value.  The device field is STILL LOCKED even when NULL is
 139  * returned.
 140  *
 141  * Currently a single global lock is implemented.
 142  */
 143 static prop_dictionary_t
 144 udev_get_dict(cdev_t dev)
 145 {
 146         prop_dictionary_t udict;
 147
 148         lockmgr(&udev_dict_lk, LK_EXCLUSIVE|LK_CANRECURSE);
 149         udict = dev->si_dict;
 150         if (udict)
 151                 prop_object_retain(udict);
 152         return udict;
 153 }
 154
 155 /*
 156  * Release the dictionary previously returned by udev_get_dict() and unlock
 157  * the device's si_dict field.  udict may be NULL.
 158  */
 159 static void
 160 udev_put_dict(cdev_t dev, prop_dictionary_t udict)
 161 {
 162         if (udict)
 163                 prop_object_release(udict);
 164         lockmgr(&udev_dict_lk, LK_RELEASE);
 165 }
 166
 167 static int
 168 _udev_dict_set_cstr(prop_dictionary_t dict, const char *key, char *str)
 169 {
 170         prop_string_t   ps;
 171
 172         KKASSERT(dict != NULL);
 173
 174         ps = prop_string_create_cstring(str);
 175         if (ps == NULL) {
 176                 return ENOMEM;
 177         }
 178
 179         if (prop_dictionary_set(dict, key, ps) == false) {
 180                 prop_object_release(ps);
 181                 return ENOMEM;
 182         }
 183
 184         prop_object_release(ps);
 185         return 0;
 186 }
 187
 188 static int
 189 _udev_dict_set_int(prop_dictionary_t dict, const char *key, int64_t val)
 190 {
 191         prop_number_t   pn;
 192
 193         KKASSERT(dict != NULL);
 194
 195         pn = prop_number_create_integer(val);
 196         if (pn == NULL)
 197                 return ENOMEM;
 198
 199         if (prop_dictionary_set(dict, key, pn) == false) {
 200                 prop_object_release(pn);
 201                 return ENOMEM;
 202         }
 203
 204         prop_object_release(pn);
 205         return 0;
 206 }
 207
 208 static int
 209 _udev_dict_set_uint(prop_dictionary_t dict, const char *key, uint64_t val)
 210 {
 211         prop_number_t   pn;
 212
 213         KKASSERT(dict != NULL);
 214
 215         pn = prop_number_create_unsigned_integer(val);
 216         if (pn == NULL)
 217                 return ENOMEM;
 218
 219         if (prop_dictionary_set(dict, key, pn) == false) {
 220                 prop_object_release(pn);
 221                 return ENOMEM;
 222         }
 223
 224         prop_object_release(pn);
 225         return 0;
 226 }
 227
 228 static int
 229 _udev_dict_delete_key(prop_dictionary_t dict, const char *key)
 230 {
 231         KKASSERT(dict != NULL);
 232
 233         prop_dictionary_remove(dict, key);
 234
 235         return 0;
 236 }
 237
 238 /*
 239  * Initialize an event dictionary, which contains three parameters to
 240  * identify the device referred to (name, devnum, kptr) and the affected key.
 241  */
 242 static prop_dictionary_t
 243 udev_init_dict_event(cdev_t dev, const char *key)
 244 {
 245         prop_dictionary_t       dict;
 246         uint64_t        kptr;
 247         int error;
 248
 249         kptr = (uint64_t)(uintptr_t)dev;
 250         KKASSERT(dev != NULL);
 251
 252         dict = prop_dictionary_create();
 253         if (dict == NULL) {
 254                 log(LOG_DEBUG, "udev_init_dict_event: prop_dictionary_create() failed\n");
 255                 return NULL;
 256         }
 257
 258         if ((error = _udev_dict_set_cstr(dict, "name", dev->si_name)))
 259                 goto error_out;
 260         if ((error = _udev_dict_set_uint(dict, "devnum", dev->si_inode)))
 261                 goto error_out;
 262         if ((error = _udev_dict_set_uint(dict, "devtype", (dev_dflags(dev) & D_TYPEMASK))))
 263                 goto error_out;
 264         if ((error = _udev_dict_set_uint(dict, "kptr", kptr)))
 265                 goto error_out;
 266         if ((error = _udev_dict_set_cstr(dict, "key", __DECONST(char *, key))))
 267                 goto error_out;
 268
 269         return dict;
 270
 271 error_out:
 272         prop_object_release(dict);
 273         return NULL;
 274 }
 275
 276 int
 277 udev_dict_set_cstr(cdev_t dev, const char *key, char *str)
 278 {
 279         prop_dictionary_t dict;
 280         prop_dictionary_t udict;
 281         int error;
 282
 283         KKASSERT(dev != NULL);
 284
 285         while ((udict = udev_get_dict(dev)) == NULL) {
 286                 error = udev_init_dict(dev);
 287                 udev_put_dict(dev, udict);
 288                 if (error)
 289                         return -1;
 290         }
 291
 292         /* Queue a key update event */
 293         dict = udev_init_dict_event(dev, key);
 294         if (dict == NULL) {
 295                 error = ENOMEM;
 296                 goto errout;
 297         }
 298
 299         if ((error = _udev_dict_set_cstr(dict, "value", str))) {
 300                 prop_object_release(dict);
 301                 goto errout;
 302         }
 303         udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
 304         prop_object_release(dict);
 305         error = _udev_dict_set_cstr(udict, key, str);
 306
 307 errout:
 308         udev_put_dict(dev, udict);
 309
 310         return error;
 311 }
 312
 313 int
 314 udev_dict_set_int(cdev_t dev, const char *key, int64_t val)
 315 {
 316         prop_dictionary_t dict;
 317         prop_dictionary_t udict;
 318         int error;
 319
 320         KKASSERT(dev != NULL);
 321
 322         while ((udict = udev_get_dict(dev)) == NULL) {
 323                 error = udev_init_dict(dev);
 324                 udev_put_dict(dev, udict);
 325                 if (error)
 326                         return -1;
 327         }
 328
 329         /* Queue a key update event */
 330         dict = udev_init_dict_event(dev, key);
 331         if (dict == NULL) {
 332                 error = ENOMEM;
 333                 goto errout;
 334         }
 335         if ((error = _udev_dict_set_int(dict, "value", val))) {
 336                 prop_object_release(dict);
 337                 goto errout;
 338         }
 339         udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
 340         prop_object_release(dict);
 341         error = _udev_dict_set_int(udict, key, val);
 342 errout:
 343         udev_put_dict(dev, udict);
 344
 345         return error;
 346 }
 347
 348 int
 349 udev_dict_set_uint(cdev_t dev, const char *key, uint64_t val)
 350 {
 351         prop_dictionary_t dict;
 352         prop_dictionary_t udict;
 353         int error;
 354
 355         KKASSERT(dev != NULL);
 356
 357         while ((udict = udev_get_dict(dev)) == NULL) {
 358                 error = udev_init_dict(dev);
 359                 udev_put_dict(dev, udict);
 360                 if (error)
 361                         return -1;
 362         }
 363
 364         /* Queue a key update event */
 365         dict = udev_init_dict_event(dev, key);
 366         if (dict == NULL) {
 367                 error = ENOMEM;
 368                 goto errout;
 369         }
 370         if ((error = _udev_dict_set_uint(dict, "value", val))) {
 371                 prop_object_release(dict);
 372                 goto errout;
 373         }
 374         udev_event_insert(UDEV_EV_KEY_UPDATE, dict);
 375         prop_object_release(dict);
 376         error = _udev_dict_set_uint(udict, key, val);
 377 errout:
 378         udev_put_dict(dev, udict);
 379
 380         return error;
 381 }
 382
 383 int
 384 udev_dict_delete_key(cdev_t dev, const char *key)
 385 {
 386         prop_dictionary_t dict;
 387         prop_dictionary_t udict;
 388         int error;
 389
 390         KKASSERT(dev != NULL);
 391         udict = udev_get_dict(dev);
 392         if (udict == NULL) {
 393                 error = ENOMEM;
 394                 goto errout;
 395         }
 396
 397         /* Queue a key removal event */
 398         dict = udev_init_dict_event(dev, key);
 399         if (dict == NULL) {
 400                 error = ENOMEM;
 401                 goto errout;
 402         }
 403         udev_event_insert(UDEV_EV_KEY_REMOVE, dict);
 404         prop_object_release(dict);
 405         error = _udev_dict_delete_key(udict, key);
 406 errout:
 407         udev_put_dict(dev, udict);
 408
 409         return error;
 410 }
 411
 412 /*
 413  * device dictionary access already locked
 414  */
 415 static int
 416 udev_init_dict(cdev_t dev)
 417 {
 418         prop_dictionary_t dict;
 419         uint64_t        kptr;
 420         int error;
 421
 422         kptr = (uint64_t)(uintptr_t)dev;
 423
 424         KKASSERT(dev != NULL);
 425
 426         if (dev->si_dict != NULL) {
 427                 log(LOG_DEBUG,
 428                     "udev_init_dict: new dict for %s, but has "
 429                     "dict already (%p)!\n",
 430                     dev->si_name, dev->si_dict);
 431                 return 0;
 432         }
 433
 434         dict = prop_dictionary_create();
 435         if (dict == NULL) {
 436                 log(LOG_DEBUG,
 437                     "udev_init_dict: prop_dictionary_create() failed\n");
 438                 return ENOMEM;
 439         }
 440
 441         if ((error = _udev_dict_set_cstr(dict, "name", dev->si_name)))
 442                 goto error_out;
 443         if ((error = _udev_dict_set_uint(dict, "devnum", dev->si_inode)))
 444                 goto error_out;
 445         if ((error = _udev_dict_set_uint(dict, "kptr", kptr)))
 446                 goto error_out;
 447         if ((error = _udev_dict_set_uint(dict, "devtype",
 448                                          (dev_dflags(dev) & D_TYPEMASK)))) {
 449                 goto error_out;
 450         }
 451
 452         /* XXX: The next 3 are marginallly useful, if at all */
 453         if ((error = _udev_dict_set_uint(dict, "uid", dev->si_uid)))
 454                 goto error_out;
 455         if ((error = _udev_dict_set_uint(dict, "gid", dev->si_gid)))
 456                 goto error_out;
 457         if ((error = _udev_dict_set_int(dict, "mode", dev->si_perms)))
 458                 goto error_out;
 459
 460         if ((error = _udev_dict_set_int(dict, "major", dev->si_umajor)))
 461                 goto error_out;
 462         if ((error = _udev_dict_set_int(dict, "minor", dev->si_uminor)))
 463                 goto error_out;
 464         if (dev->si_ops->head.name != NULL) {
 465                 if ((error = _udev_dict_set_cstr(dict, "driver",
 466                     __DECONST(char *, dev->si_ops->head.name))))
 467                         goto error_out;
 468         }
 469
 470         dev->si_dict = dict;
 471         return 0;
 472
 473 error_out:
 474         dev->si_dict = NULL;
 475         prop_object_release(dict);
 476         return error;
 477 }
 478
 479 /*
 480  * device dictionary access already locked
 481  */
 482 static int
 483 udev_destroy_dict(cdev_t dev)
 484 {
 485         prop_dictionary_t udict;
 486
 487         KKASSERT(dev != NULL);
 488         udict = udev_get_dict(dev);
 489
 490         /* field is now locked, use directly to handle races */
 491         if (dev->si_dict) {
 492                 prop_object_release(dev->si_dict);
 493                 dev->si_dict = NULL;
 494         }
 495         udev_put_dict(dev, udict);
 496
 497         return 0;
 498 }
 499
 500 static void
 501 udev_event_insert(int ev_type, prop_dictionary_t dict)
 502 {
 503         struct udev_event_kernel *ev;
 504         prop_dictionary_t dict_copy;
 505
 506         /* Only start queing events after client has initiated properly */
 507         if (udev_initiated_count) {
 508                 dict_copy = prop_dictionary_copy(dict);
 509                 if (dict_copy == NULL)
 510                         return;
 511                 ev = objcache_get(udev_event_kernel_cache, M_WAITOK);
 512                 ev->ev.ev_dict = dict_copy;
 513                 ev->ev.ev_type = ev_type;
 514
 515                 lockmgr(&udev_lk, LK_EXCLUSIVE);
 516                 TAILQ_INSERT_TAIL(&udev_evq, ev, link);
 517                 ++udev_evqlen;
 518                 ++udev_seq;
 519                 if (udev_seqwait)
 520                         wakeup(&udev_seqwait);
 521                 lockmgr(&udev_lk, LK_RELEASE);
 522                 wakeup(&udev_evq);
 523                 KNOTE(&udev_kq.ki_note, 0);
 524         } else if (udev_open_count) {
 525                 lockmgr(&udev_lk, LK_EXCLUSIVE);
 526                 ++udev_seq;
 527                 if (udev_seqwait)
 528                         wakeup(&udev_seqwait);
 529                 lockmgr(&udev_lk, LK_RELEASE);
 530                 KNOTE(&udev_kq.ki_note, 0);
 531         }
 532 }
 533
 534 static void
 535 udev_clean_events_locked(void)
 536 {
 537         struct udev_event_kernel *ev;
 538
 539         while ((ev = TAILQ_FIRST(&udev_evq)) &&
 540                ev->ev.ev_dict != NULL) {
 541                 TAILQ_REMOVE(&udev_evq, ev, link);
 542                 objcache_put(udev_event_kernel_cache, ev);
 543                 --udev_evqlen;
 544         }
 545 }
 546
 547 static char *
 548 udev_event_externalize(struct udev_event_kernel *ev)
 549 {
 550         prop_dictionary_t       dict;
 551         char *xml;
 552         int error;
 553
 554         dict = prop_dictionary_create();
 555         if (dict == NULL) {
 556                 log(LOG_DEBUG,
 557                     "udev_event_externalize: prop_dictionary_create() failed\n");
 558                 return NULL;
 559         }
 560
 561         if ((error = _udev_dict_set_int(dict, "evtype", ev->ev.ev_type))) {
 562                 prop_object_release(dict);
 563                 return NULL;
 564         }
 565
 566         if (prop_dictionary_set(dict, "evdict", ev->ev.ev_dict) == false) {
 567                 prop_object_release(dict);
 568                 return NULL;
 569         }
 570
 571         prop_object_release(ev->ev.ev_dict);
 572
 573         xml = prop_dictionary_externalize(dict);
 574
 575         prop_object_release(dict);
 576
 577         return xml;
 578 }
 579
 580 int
 581 udev_event_attach(cdev_t dev, char *name, int alias)
 582 {
 583         prop_dictionary_t dict;
 584         prop_dictionary_t udict;
 585         int error;
 586
 587         KKASSERT(dev != NULL);
 588
 589         error = ENOMEM;
 590
 591         udict = udev_get_dict(dev);
 592         if (alias) {
 593                 if (udict == NULL)
 594                         goto error_out;
 595                 dict = prop_dictionary_copy(udict);
 596                 if (dict == NULL)
 597                         goto error_out;
 598
 599                 if ((error = _udev_dict_set_cstr(dict, "name", name))) {
 600                         prop_object_release(dict);
 601                         goto error_out;
 602                 }
 603
 604                 _udev_dict_set_int(dict, "alias", 1);
 605
 606                 udev_event_insert(UDEV_EVENT_ATTACH, dict);
 607                 prop_object_release(dict);
 608         } else {
 609                 while (udict == NULL) {
 610                         error = udev_init_dict(dev);
 611                         if (error)
 612                                 goto error_out;
 613                         udev_put_dict(dev, udict);
 614                         udict = udev_get_dict(dev);
 615                 }
 616                 _udev_dict_set_int(udict, "alias", 0);
 617                 udev_event_insert(UDEV_EVENT_ATTACH, udict);
 618         }
 619 error_out:
 620         udev_put_dict(dev, udict);
 621
 622         return error;
 623 }
 624
 625 int
 626 udev_event_detach(cdev_t dev, char *name, int alias)
 627 {
 628         prop_dictionary_t dict;
 629         prop_dictionary_t udict;
 630
 631         KKASSERT(dev != NULL);
 632
 633         udict = udev_get_dict(dev);
 634         if (alias) {
 635                 dict = prop_dictionary_copy(udict);
 636                 if (dict == NULL)
 637                         goto error_out;
 638
 639                 if (_udev_dict_set_cstr(dict, "name", name)) {
 640                         prop_object_release(dict);
 641                         goto error_out;
 642                 }
 643
 644                 _udev_dict_set_int(dict, "alias", 1);
 645
 646                 udev_event_insert(UDEV_EVENT_DETACH, dict);
 647                 prop_object_release(dict);
 648         } else {
 649                 if (udict)
 650                         udev_event_insert(UDEV_EVENT_DETACH, udict);
 651         }
 652
 653 error_out:
 654         udev_destroy_dict(dev);
 655         udev_put_dict(dev, udict);
 656
 657         return 0;
 658 }
 659
 660 /*
 661  * Allow multiple opens.  Each opener gets a different device.
 662  * Messages are replicated to all devices using a marker system.
 663  */
 664 static int
 665 udev_dev_clone(struct dev_clone_args *ap)
 666 {
 667         struct udev_softc *softc;
 668         int unit;
 669
 670         unit = devfs_clone_bitmap_get(&DEVFS_CLONE_BITMAP(udev), 1000);
 671         if (unit < 0) {
 672                 ap->a_dev = NULL;
 673                 return 1;
 674         }
 675
 676         softc = kmalloc(sizeof(*softc), M_UDEV, M_WAITOK | M_ZERO);
 677         softc->unit = unit;
 678         lockmgr(&udev_lk, LK_EXCLUSIVE);
 679         TAILQ_INSERT_TAIL(&udevq, softc, entry);
 680         lockmgr(&udev_lk, LK_RELEASE);
 681
 682         softc->dev = make_only_dev(&udev_dev_ops, unit, ap->a_cred->cr_ruid,
 683                                    0, 0600, "udevs/%d", unit);
 684         softc->dev->si_drv1 = softc;
 685         ap->a_dev = softc->dev;
 686         return 0;
 687 }
 688
 689 /*
 690  * dev stuff
 691  */
 692 static int
 693 udev_dev_open(struct dev_open_args *ap)
 694 {
 695         struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
 696
 697         lockmgr(&udev_lk, LK_EXCLUSIVE);
 698         if (softc == NULL || softc->opened) {
 699                 lockmgr(&udev_lk, LK_RELEASE);
 700                 return EBUSY;
 701         }
 702         softc->opened = 1;
 703         ++udev_open_count;
 704         lockmgr(&udev_lk, LK_RELEASE);
 705
 706         return 0;
 707 }
 708
 709 static int
 710 udev_dev_close(struct dev_close_args *ap)
 711 {
 712         struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
 713
 714         KKASSERT(softc->dev == ap->a_head.a_dev);
 715         KKASSERT(softc->opened == 1);
 716
 717         destroy_dev(ap->a_head.a_dev);
 718         lockmgr(&udev_lk, LK_EXCLUSIVE);
 719         TAILQ_REMOVE(&udevq, softc, entry);
 720
 721         if (softc->initiated) {
 722                 TAILQ_REMOVE(&udev_evq, &softc->marker, link);
 723                 softc->initiated = 0;
 724                 --udev_initiated_count;
 725                 udev_clean_events_locked();
 726         }
 727         softc->opened = 0;
 728         softc->dev = NULL;
 729         ap->a_head.a_dev->si_drv1 = NULL;
 730         --udev_open_count;
 731         lockmgr(&udev_lk, LK_RELEASE);
 732
 733         /*
 734          * WARNING! devfs_clone_bitmap_put() interacts with the devfs
 735          *          thread, avoid deadlocks by ensuring we are unlocked
 736          *          before calling.
 737          */
 738         devfs_clone_bitmap_put(&DEVFS_CLONE_BITMAP(udev), softc->unit);
 739         wakeup(&udev_evq);
 740
 741         kfree(softc, M_UDEV);
 742
 743         return 0;
 744 }
 745
 746 static struct filterops udev_dev_read_filtops =
 747         { FILTEROP_ISFD | FILTEROP_MPSAFE, NULL,
 748           udev_dev_filter_detach, udev_dev_filter_read };
 749
 750 static int
 751 udev_dev_kqfilter(struct dev_kqfilter_args *ap)
 752 {
 753         struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
 754         struct knote *kn = ap->a_kn;
 755         struct klist *klist;
 756
 757         ap->a_result = 0;
 758         lockmgr(&udev_lk, LK_EXCLUSIVE);
 759
 760         switch (kn->kn_filter) {
 761         case EVFILT_READ:
 762                 kn->kn_fop = &udev_dev_read_filtops;
 763                 kn->kn_hook = (caddr_t)softc;
 764                 break;
 765         default:
 766                 ap->a_result = EOPNOTSUPP;
 767                 lockmgr(&udev_lk, LK_RELEASE);
 768                 return (0);
 769         }
 770
 771         klist = &udev_kq.ki_note;
 772         knote_insert(klist, kn);
 773
 774         lockmgr(&udev_lk, LK_RELEASE);
 775
 776         return (0);
 777 }
 778
 779 static void
 780 udev_dev_filter_detach(struct knote *kn)
 781 {
 782         struct klist *klist;
 783
 784         lockmgr(&udev_lk, LK_EXCLUSIVE);
 785         klist = &udev_kq.ki_note;
 786         knote_remove(klist, kn);
 787         lockmgr(&udev_lk, LK_RELEASE);
 788 }
 789
 790 static int
 791 udev_dev_filter_read(struct knote *kn, long hint)
 792 {
 793         struct udev_softc *softc = (void *)kn->kn_hook;
 794         struct udev_event_kernel *ev;
 795         int ready = 0;
 796
 797         lockmgr(&udev_lk, LK_EXCLUSIVE);
 798         if (softc->initiated) {
 799                 ev = TAILQ_NEXT(&softc->marker, link);
 800                 while (ev && ev->ev.ev_dict == NULL)
 801                         ev = TAILQ_NEXT(ev, link);
 802                 if (ev)
 803                         ready = 1;
 804         }
 805         lockmgr(&udev_lk, LK_RELEASE);
 806
 807         return (ready);
 808 }
 809
 810 static int
 811 udev_dev_read(struct dev_read_args *ap)
 812 {
 813         struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
 814         struct udev_event_kernel *ev;
 815         struct uio *uio = ap->a_uio;
 816         char    *xml;
 817         size_t  len;
 818         int     error;
 819
 820         lockmgr(&udev_lk, LK_EXCLUSIVE);
 821
 822         /*
 823          * Automatically enable message collection if it has not already
 824          * been enabled.
 825          */
 826         if (softc->initiated == 0) {
 827                 softc->initiated = 1;
 828                 ++udev_initiated_count;
 829                 TAILQ_INSERT_HEAD(&udev_evq, &softc->marker, link);
 830         }
 831
 832         /*
 833          * Loop, sleep interruptably until we get an event or signal.
 834          */
 835         error = 0;
 836         for (;;) {
 837                 if (softc->initiated) {
 838                         ev = TAILQ_NEXT(&softc->marker, link);
 839                         while (ev && ev->ev.ev_dict == NULL)
 840                                 ev = TAILQ_NEXT(ev, link);
 841                         if (ev) {
 842                                 if ((xml = udev_event_externalize(ev)) == NULL) {
 843                                         error = ENOMEM;
 844                                         break;
 845                                 }
 846                                 len = strlen(xml) + 1; /* include terminator */
 847                                 if (uio->uio_resid < len)
 848                                         error = ENOMEM;
 849                                 else
 850                                         error = uiomove((caddr_t)xml, len, uio);
 851                                 kfree(xml, M_TEMP);
 852
 853                                 /*
 854                                  * Move the marker
 855                                  */
 856                                 TAILQ_REMOVE(&udev_evq, &softc->marker, link);
 857                                 TAILQ_INSERT_AFTER(&udev_evq,
 858                                                    ev, &softc->marker, link);
 859                                 udev_clean_events_locked();
 860                                 break;
 861                         }
 862                 }
 863                 if (ap->a_ioflag & IO_NDELAY) {
 864                         error = EWOULDBLOCK;
 865                         break;
 866                 }
 867                 if ((error = lksleep(&udev_evq, &udev_lk, PCATCH, "udevq", 0)))
 868                         break;
 869         }
 870
 871         lockmgr(&udev_lk, LK_RELEASE);
 872         return error;
 873 }
 874
 875 static int
 876 udev_dev_ioctl(struct dev_ioctl_args *ap)
 877 {
 878         struct udev_softc *softc = ap->a_head.a_dev->si_drv1;
 879         prop_dictionary_t dict;
 880         prop_object_t   po;
 881         prop_string_t   ps;
 882         struct plistref *pref;
 883         int i, error;
 884         int seq;
 885
 886         error = 0;
 887
 888         switch(ap->a_cmd) {
 889         case UDEVPROP:
 890                 /* Use proplib(3) for userspace/kernel communication */
 891                 pref = (struct plistref *)ap->a_data;
 892                 error = prop_dictionary_copyin_ioctl(pref, ap->a_cmd, &dict);
 893                 if (error)
 894                         return error;
 895
 896                 po = prop_dictionary_get(dict, "command");
 897                 if (po == NULL || prop_object_type(po) != PROP_TYPE_STRING) {
 898                         log(LOG_DEBUG, "udev: prop_dictionary_get() failed\n");
 899                         prop_object_release(dict);
 900                         return EINVAL;
 901                 }
 902
 903                 ps = po;
 904                 /* Handle cmd */
 905                 for(i = 0; cmd_fn[i].cmd != NULL; i++) {
 906                         if (prop_string_equals_cstring(ps, cmd_fn[i].cmd))
 907                                 break;
 908                 }
 909
 910                 if (cmd_fn[i].cmd != NULL) {
 911                         error = cmd_fn[i].fn(softc, pref, ap->a_cmd, dict);
 912                 } else {
 913                         error = EINVAL;
 914                 }
 915
 916                 //prop_object_release(po);
 917                 prop_object_release(dict);
 918                 break;
 919         case UDEVWAIT:
 920                 /*
 921                  * Wait for events based on sequence number.  Updates
 922                  * sequence number for loop.
 923                  */
 924                 lockmgr(&udev_lk, LK_EXCLUSIVE);
 925                 seq = *(int *)ap->a_data;
 926                 ++udev_seqwait;
 927                 while (seq == udev_seq) {
 928                         error = lksleep(&udev_seqwait, &udev_lk,
 929                                         PCATCH, "udevw", 0);
 930                         if (error)
 931                                 break;
 932                 }
 933                 --udev_seqwait;
 934                 *(int *)ap->a_data = udev_seq;
 935                 lockmgr(&udev_lk, LK_RELEASE);
 936                 break;
 937         default:
 938                 error = ENOTTY; /* Inappropriate ioctl for device */
 939                 break;
 940         }
 941
 942         return(error);
 943 }
 944
 945 static void
 946 udev_getdevs_scan_callback(char *name, cdev_t cdev, bool is_alias, void *arg)
 947 {
 948         struct udev_prop_ctx *ctx = arg;
 949
 950         KKASSERT(arg != NULL);
 951
 952         if (cdev->si_dict == NULL)
 953                 return;
 954
 955         if (prop_array_add(ctx->cdevs, cdev->si_dict) == false) {
 956                 ctx->error = EINVAL;
 957                 return;
 958         }
 959 }
 960
 961 static int
 962 udev_getdevs_ioctl(struct udev_softc *softc, struct plistref *pref,
 963                    u_long cmd, prop_dictionary_t dict)
 964 {
 965         prop_dictionary_t odict;
 966         struct udev_prop_ctx ctx;
 967         int error;
 968
 969         /*
 970          * Ensure event notification is enabled before doing the devfs
 971          * scan so nothing gets missed.
 972          */
 973         lockmgr(&udev_lk, LK_EXCLUSIVE);
 974         if (softc->initiated == 0) {
 975                 softc->initiated = 1;
 976                 ++udev_initiated_count;
 977                 TAILQ_INSERT_HEAD(&udev_evq, &softc->marker, link);
 978         }
 979         lockmgr(&udev_lk, LK_RELEASE);
 980
 981         /*
 982          * Devfs scan to build full dictionary.
 983          */
 984         ctx.error = 0;
 985         ctx.cdevs = prop_array_create();
 986         if (ctx.cdevs == NULL) {
 987                 log(LOG_DEBUG,
 988                     "udev_getdevs_ioctl: prop_array_create() failed\n");
 989                 return EINVAL;
 990         }
 991
 992         devfs_scan_callback(udev_getdevs_scan_callback, &ctx);
 993
 994         if (ctx.error != 0) {
 995                 prop_object_release(ctx.cdevs);
 996                 return (ctx.error);
 997         }
 998
 999         odict = prop_dictionary_create();
1000         if (odict == NULL) {
1001                 return ENOMEM;
1002         }
1003
1004         if ((prop_dictionary_set(odict, "array", ctx.cdevs)) == 0) {
1005                 log(LOG_DEBUG,
1006                     "udev_getdevs_ioctl: prop_dictionary_set failed\n");
1007                 prop_object_release(odict);
1008                 return ENOMEM;
1009         }
1010
1011         error = prop_dictionary_copyout_ioctl(pref, cmd, odict);
1012
1013         prop_object_release(odict);
1014         return error;
1015 }
1016
1017
1018 /*
1019  * SYSINIT stuff
1020  */
1021 static void
1022 udev_init(void)
1023 {
1024         lockinit(&udev_lk, "udevlk", 0, LK_CANRECURSE);
1025         TAILQ_INIT(&udevq);
1026         TAILQ_INIT(&udev_evq);
1027         udev_event_kernel_cache = objcache_create_simple(M_UDEV, sizeof(struct udev_event_kernel));
1028 }
1029
1030 static void
1031 udev_uninit(void)
1032 {
1033         objcache_destroy(udev_event_kernel_cache);
1034 }
1035
1036 static void
1037 udev_dev_init(void)
1038 {
1039         udev_dev = make_autoclone_dev(&udev_dev_ops, &DEVFS_CLONE_BITMAP(udev),
1040                                       udev_dev_clone,
1041                                       UID_ROOT, GID_WHEEL, 0600, "udev");
1042 }
1043
1044 static void
1045 udev_dev_uninit(void)
1046 {
1047         destroy_dev(udev_dev);
1048 }
1049
1050 SYSINIT(subr_udev_register, SI_SUB_CREATE_INIT, SI_ORDER_ANY,
1051         udev_init, NULL);
1052 SYSUNINIT(subr_udev_register, SI_SUB_CREATE_INIT, SI_ORDER_ANY,
1053         udev_uninit, NULL);
1054 SYSINIT(subr_udev_dev_register, SI_SUB_DRIVERS, SI_ORDER_ANY,
1055         udev_dev_init, NULL);
1056 SYSUNINIT(subr_udev_dev_register, SI_SUB_DRIVERS, SI_ORDER_ANY,
1057         udev_dev_uninit, NULL);