1 /* $NetBSD: kern_drvctl.c,v 1.21 2009/01/03 03:31:23 yamt Exp $ */ 2 3 /* 4 * Copyright (c) 2004 5 * Matthias Drochner. All rights reserved. 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 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions, and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: kern_drvctl.c,v 1.21 2009/01/03 03:31:23 yamt Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/kernel.h> 35 #include <sys/conf.h> 36 #include <sys/device.h> 37 #include <sys/event.h> 38 #include <sys/malloc.h> 39 #include <sys/kmem.h> 40 #include <sys/ioctl.h> 41 #include <sys/fcntl.h> 42 #include <sys/file.h> 43 #include <sys/filedesc.h> 44 #include <sys/select.h> 45 #include <sys/poll.h> 46 #include <sys/drvctlio.h> 47 #include <sys/devmon.h> 48 49 struct drvctl_event { 50 TAILQ_ENTRY(drvctl_event) dce_link; 51 prop_dictionary_t dce_event; 52 }; 53 54 TAILQ_HEAD(drvctl_queue, drvctl_event); 55 56 static struct drvctl_queue drvctl_eventq; /* FIFO */ 57 static kcondvar_t drvctl_cond; 58 static kmutex_t drvctl_lock; 59 static int drvctl_nopen = 0, drvctl_eventcnt = 0; 60 static struct selinfo drvctl_rdsel; 61 62 #define DRVCTL_EVENTQ_DEPTH 64 /* arbitrary queue limit */ 63 64 dev_type_open(drvctlopen); 65 66 const struct cdevsw drvctl_cdevsw = { 67 drvctlopen, nullclose, nullread, nullwrite, noioctl, 68 nostop, notty, nopoll, nommap, nokqfilter, D_OTHER 69 }; 70 71 void drvctlattach(int); 72 73 static int drvctl_read(struct file *, off_t *, struct uio *, 74 kauth_cred_t, int); 75 static int drvctl_write(struct file *, off_t *, struct uio *, 76 kauth_cred_t, int); 77 static int drvctl_ioctl(struct file *, u_long, void *); 78 static int drvctl_poll(struct file *, int); 79 static int drvctl_close(struct file *); 80 81 static const struct fileops drvctl_fileops = { 82 drvctl_read, 83 drvctl_write, 84 drvctl_ioctl, 85 fnullop_fcntl, 86 drvctl_poll, 87 fbadop_stat, 88 drvctl_close, 89 fnullop_kqfilter 90 }; 91 92 #define MAXLOCATORS 100 93 94 static int drvctl_command(struct lwp *, struct plistref *, u_long, int); 95 static int drvctl_getevent(struct lwp *, struct plistref *, u_long, int); 96 97 void 98 drvctl_init(void) 99 { 100 TAILQ_INIT(&drvctl_eventq); 101 mutex_init(&drvctl_lock, MUTEX_DEFAULT, IPL_NONE); 102 cv_init(&drvctl_cond, "devmon"); 103 selinit(&drvctl_rdsel); 104 } 105 106 void 107 devmon_insert(const char *event, prop_dictionary_t ev) 108 { 109 struct drvctl_event *dce, *odce; 110 111 mutex_enter(&drvctl_lock); 112 113 if (drvctl_nopen == 0) { 114 mutex_exit(&drvctl_lock); 115 return; 116 } 117 118 /* Fill in mandatory member */ 119 if (!prop_dictionary_set_cstring_nocopy(ev, "event", event)) { 120 prop_object_release(ev); 121 mutex_exit(&drvctl_lock); 122 return; 123 } 124 125 dce = kmem_alloc(sizeof(*dce), KM_SLEEP); 126 if (dce == NULL) { 127 mutex_exit(&drvctl_lock); 128 return; 129 } 130 131 dce->dce_event = ev; 132 133 if (drvctl_eventcnt == DRVCTL_EVENTQ_DEPTH) { 134 odce = TAILQ_FIRST(&drvctl_eventq); 135 TAILQ_REMOVE(&drvctl_eventq, odce, dce_link); 136 prop_object_release(odce->dce_event); 137 kmem_free(odce, sizeof(*odce)); 138 --drvctl_eventcnt; 139 } 140 141 TAILQ_INSERT_TAIL(&drvctl_eventq, dce, dce_link); 142 ++drvctl_eventcnt; 143 cv_broadcast(&drvctl_cond); 144 selnotify(&drvctl_rdsel, 0, 0); 145 146 mutex_exit(&drvctl_lock); 147 } 148 149 int 150 drvctlopen(dev_t dev, int flags, int mode, struct lwp *l) 151 { 152 struct file *fp; 153 int fd; 154 int ret; 155 156 ret = fd_allocfile(&fp, &fd); 157 if (ret) 158 return (ret); 159 160 /* XXX setup context */ 161 mutex_enter(&drvctl_lock); 162 ret = fd_clone(fp, fd, flags, &drvctl_fileops, /* context */NULL); 163 ++drvctl_nopen; 164 mutex_exit(&drvctl_lock); 165 166 return ret; 167 } 168 169 static int 170 pmdevbyname(u_long cmd, struct devpmargs *a) 171 { 172 struct device *d; 173 174 if ((d = device_find_by_xname(a->devname)) == NULL) 175 return ENXIO; 176 177 switch (cmd) { 178 case DRVSUSPENDDEV: 179 return pmf_device_recursive_suspend(d, PMF_F_NONE) ? 0 : EBUSY; 180 case DRVRESUMEDEV: 181 if (a->flags & DEVPM_F_SUBTREE) { 182 return pmf_device_resume_subtree(d, PMF_F_NONE) 183 ? 0 : EBUSY; 184 } else { 185 return pmf_device_recursive_resume(d, PMF_F_NONE) 186 ? 0 : EBUSY; 187 } 188 default: 189 return EPASSTHROUGH; 190 } 191 } 192 193 static int 194 listdevbyname(struct devlistargs *l) 195 { 196 device_t d, child; 197 deviter_t di; 198 int cnt = 0, idx, error = 0; 199 200 if ((d = device_find_by_xname(l->l_devname)) == NULL) 201 return ENXIO; 202 203 for (child = deviter_first(&di, 0); child != NULL; 204 child = deviter_next(&di)) { 205 if (device_parent(child) != d) 206 continue; 207 idx = cnt++; 208 if (l->l_childname == NULL || idx >= l->l_children) 209 continue; 210 error = copyoutstr(device_xname(child), l->l_childname[idx], 211 sizeof(l->l_childname[idx]), NULL); 212 if (error != 0) 213 break; 214 } 215 deviter_release(&di); 216 217 l->l_children = cnt; 218 return error; 219 } 220 221 static int 222 detachdevbyname(const char *devname) 223 { 224 struct device *d; 225 226 if ((d = device_find_by_xname(devname)) == NULL) 227 return ENXIO; 228 229 #ifndef XXXFULLRISK 230 /* 231 * If the parent cannot be notified, it might keep 232 * pointers to the detached device. 233 * There might be a private notification mechanism, 234 * but better play save here. 235 */ 236 if (d->dv_parent && !d->dv_parent->dv_cfattach->ca_childdetached) 237 return (ENOTSUP); 238 #endif 239 return (config_detach(d, 0)); 240 } 241 242 static int 243 rescanbus(const char *busname, const char *ifattr, 244 int numlocators, const int *locators) 245 { 246 int i, rc; 247 struct device *d; 248 const struct cfiattrdata * const *ap; 249 250 /* XXX there should be a way to get limits and defaults (per device) 251 from config generated data */ 252 int locs[MAXLOCATORS]; 253 for (i = 0; i < MAXLOCATORS; i++) 254 locs[i] = -1; 255 256 for (i = 0; i < numlocators;i++) 257 locs[i] = locators[i]; 258 259 if ((d = device_find_by_xname(busname)) == NULL) 260 return ENXIO; 261 262 /* 263 * must support rescan, and must have something 264 * to attach to 265 */ 266 if (!d->dv_cfattach->ca_rescan || 267 !d->dv_cfdriver->cd_attrs) 268 return (ENODEV); 269 270 /* allow to omit attribute if there is exactly one */ 271 if (!ifattr) { 272 if (d->dv_cfdriver->cd_attrs[1]) 273 return (EINVAL); 274 ifattr = d->dv_cfdriver->cd_attrs[0]->ci_name; 275 } else { 276 /* check for valid attribute passed */ 277 for (ap = d->dv_cfdriver->cd_attrs; *ap; ap++) 278 if (!strcmp((*ap)->ci_name, ifattr)) 279 break; 280 if (!*ap) 281 return (EINVAL); 282 } 283 284 rc = (*d->dv_cfattach->ca_rescan)(d, ifattr, locs); 285 config_deferred(NULL); 286 return rc; 287 } 288 289 static int 290 drvctl_read(struct file *fp, off_t *offp, struct uio *uio, kauth_cred_t cred, 291 int flags) 292 { 293 return (ENODEV); 294 } 295 296 static int 297 drvctl_write(struct file *fp, off_t *offp, struct uio *uio, kauth_cred_t cred, 298 int flags) 299 { 300 return (ENODEV); 301 } 302 303 static int 304 drvctl_ioctl(struct file *fp, u_long cmd, void *data) 305 { 306 int res; 307 char *ifattr; 308 int *locs; 309 310 switch (cmd) { 311 case DRVSUSPENDDEV: 312 case DRVRESUMEDEV: 313 #define d ((struct devpmargs *)data) 314 res = pmdevbyname(cmd, d); 315 #undef d 316 break; 317 case DRVLISTDEV: 318 res = listdevbyname((struct devlistargs *)data); 319 break; 320 case DRVDETACHDEV: 321 #define d ((struct devdetachargs *)data) 322 res = detachdevbyname(d->devname); 323 #undef d 324 break; 325 case DRVRESCANBUS: 326 #define d ((struct devrescanargs *)data) 327 d->busname[sizeof(d->busname) - 1] = '\0'; 328 329 /* XXX better copyin? */ 330 if (d->ifattr[0]) { 331 d->ifattr[sizeof(d->ifattr) - 1] = '\0'; 332 ifattr = d->ifattr; 333 } else 334 ifattr = 0; 335 336 if (d->numlocators) { 337 if (d->numlocators > MAXLOCATORS) 338 return (EINVAL); 339 locs = malloc(d->numlocators * sizeof(int), M_DEVBUF, 340 M_WAITOK); 341 res = copyin(d->locators, locs, 342 d->numlocators * sizeof(int)); 343 if (res) { 344 free(locs, M_DEVBUF); 345 return (res); 346 } 347 } else 348 locs = 0; 349 res = rescanbus(d->busname, ifattr, d->numlocators, locs); 350 if (locs) 351 free(locs, M_DEVBUF); 352 #undef d 353 break; 354 case DRVCTLCOMMAND: 355 res = drvctl_command(curlwp, (struct plistref *)data, cmd, 356 fp->f_flag); 357 break; 358 case DRVGETEVENT: 359 res = drvctl_getevent(curlwp, (struct plistref *)data, cmd, 360 fp->f_flag); 361 break; 362 default: 363 return (EPASSTHROUGH); 364 } 365 return (res); 366 } 367 368 static int 369 drvctl_poll(struct file *fp, int events) 370 { 371 int revents = 0; 372 373 if (!TAILQ_EMPTY(&drvctl_eventq)) 374 revents |= events & (POLLIN | POLLRDNORM); 375 else 376 selrecord(curlwp, &drvctl_rdsel); 377 378 return revents; 379 } 380 381 static int 382 drvctl_close(struct file *fp) 383 { 384 struct drvctl_event *dce; 385 386 /* XXX free context */ 387 mutex_enter(&drvctl_lock); 388 KASSERT(drvctl_nopen > 0); 389 --drvctl_nopen; 390 if (drvctl_nopen == 0) { 391 /* flush queue */ 392 while ((dce = TAILQ_FIRST(&drvctl_eventq)) != NULL) { 393 TAILQ_REMOVE(&drvctl_eventq, dce, dce_link); 394 KASSERT(drvctl_eventcnt > 0); 395 --drvctl_eventcnt; 396 prop_object_release(dce->dce_event); 397 kmem_free(dce, sizeof(*dce)); 398 } 399 } 400 mutex_exit(&drvctl_lock); 401 402 return (0); 403 } 404 405 void 406 drvctlattach(int arg) 407 { 408 } 409 410 /***************************************************************************** 411 * Driver control command processing engine 412 *****************************************************************************/ 413 414 static int 415 drvctl_command_get_properties(struct lwp *l, 416 prop_dictionary_t command_dict, 417 prop_dictionary_t results_dict) 418 { 419 prop_dictionary_t args_dict; 420 prop_string_t devname_string; 421 device_t dev; 422 deviter_t di; 423 424 args_dict = prop_dictionary_get(command_dict, "drvctl-arguments"); 425 if (args_dict == NULL) 426 return (EINVAL); 427 428 devname_string = prop_dictionary_get(args_dict, "device-name"); 429 if (devname_string == NULL) 430 return (EINVAL); 431 432 for (dev = deviter_first(&di, 0); dev != NULL; 433 dev = deviter_next(&di)) { 434 if (prop_string_equals_cstring(devname_string, 435 device_xname(dev))) { 436 prop_dictionary_set(results_dict, "drvctl-result-data", 437 device_properties(dev)); 438 break; 439 } 440 } 441 442 deviter_release(&di); 443 444 if (dev == NULL) 445 return (ESRCH); 446 447 return (0); 448 } 449 450 struct drvctl_command_desc { 451 const char *dcd_name; /* command name */ 452 int (*dcd_func)(struct lwp *, /* handler function */ 453 prop_dictionary_t, 454 prop_dictionary_t); 455 int dcd_rw; /* read or write required */ 456 }; 457 458 static const struct drvctl_command_desc drvctl_command_table[] = { 459 { .dcd_name = "get-properties", 460 .dcd_func = drvctl_command_get_properties, 461 .dcd_rw = FREAD, 462 }, 463 464 { .dcd_name = NULL } 465 }; 466 467 static int 468 drvctl_command(struct lwp *l, struct plistref *pref, u_long ioctl_cmd, 469 int fflag) 470 { 471 prop_dictionary_t command_dict, results_dict; 472 prop_string_t command_string; 473 const struct drvctl_command_desc *dcd; 474 int error; 475 476 error = prop_dictionary_copyin_ioctl(pref, ioctl_cmd, &command_dict); 477 if (error) 478 return (error); 479 480 results_dict = prop_dictionary_create(); 481 if (results_dict == NULL) { 482 prop_object_release(command_dict); 483 return (ENOMEM); 484 } 485 486 command_string = prop_dictionary_get(command_dict, "drvctl-command"); 487 if (command_string == NULL) { 488 error = EINVAL; 489 goto out; 490 } 491 492 for (dcd = drvctl_command_table; dcd->dcd_name != NULL; dcd++) { 493 if (prop_string_equals_cstring(command_string, 494 dcd->dcd_name)) 495 break; 496 } 497 498 if (dcd->dcd_name == NULL) { 499 error = EINVAL; 500 goto out; 501 } 502 503 if ((fflag & dcd->dcd_rw) == 0) { 504 error = EPERM; 505 goto out; 506 } 507 508 error = (*dcd->dcd_func)(l, command_dict, results_dict); 509 510 prop_dictionary_set_int32(results_dict, "drvctl-error", error); 511 512 error = prop_dictionary_copyout_ioctl(pref, ioctl_cmd, results_dict); 513 out: 514 prop_object_release(command_dict); 515 prop_object_release(results_dict); 516 return (error); 517 } 518 519 static int 520 drvctl_getevent(struct lwp *l, struct plistref *pref, u_long ioctl_cmd, 521 int fflag) 522 { 523 struct drvctl_event *dce; 524 int ret; 525 526 if ((fflag & (FREAD|FWRITE)) != (FREAD|FWRITE)) 527 return (EPERM); 528 529 mutex_enter(&drvctl_lock); 530 while ((dce = TAILQ_FIRST(&drvctl_eventq)) == NULL) { 531 if (fflag & O_NONBLOCK) { 532 mutex_exit(&drvctl_lock); 533 return (EWOULDBLOCK); 534 } 535 536 ret = cv_wait_sig(&drvctl_cond, &drvctl_lock); 537 if (ret) { 538 mutex_exit(&drvctl_lock); 539 return (ret); 540 } 541 } 542 TAILQ_REMOVE(&drvctl_eventq, dce, dce_link); 543 KASSERT(drvctl_eventcnt > 0); 544 --drvctl_eventcnt; 545 mutex_exit(&drvctl_lock); 546 547 ret = prop_dictionary_copyout_ioctl(pref, ioctl_cmd, dce->dce_event); 548 549 prop_object_release(dce->dce_event); 550 kmem_free(dce, sizeof(*dce)); 551 552 return (ret); 553 } 554