1 /* $NetBSD: kern_drvctl.c,v 1.18 2008/05/30 15:30:37 freza 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 1.18 2008/05/30 15:30:37 freza 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/drvctlio.h> 45 #include <sys/devmon.h> 46 47 struct drvctl_event { 48 TAILQ_ENTRY(drvctl_event) dce_link; 49 prop_dictionary_t dce_event; 50 }; 51 52 TAILQ_HEAD(drvctl_queue, drvctl_event); 53 54 static struct drvctl_queue drvctl_eventq; /* FIFO */ 55 static kcondvar_t drvctl_cond; 56 static kmutex_t drvctl_lock; 57 static int drvctl_nopen = 0, drvctl_eventcnt = 0; 58 59 #define DRVCTL_EVENTQ_DEPTH 64 /* arbitrary queue limit */ 60 61 dev_type_open(drvctlopen); 62 63 const struct cdevsw drvctl_cdevsw = { 64 drvctlopen, nullclose, nullread, nullwrite, noioctl, 65 nostop, notty, nopoll, nommap, nokqfilter, D_OTHER 66 }; 67 68 void drvctlattach(int); 69 70 static int drvctl_read(struct file *, off_t *, struct uio *, 71 kauth_cred_t, int); 72 static int drvctl_write(struct file *, off_t *, struct uio *, 73 kauth_cred_t, int); 74 static int drvctl_ioctl(struct file *, u_long, void *); 75 static int drvctl_close(struct file *); 76 77 static const struct fileops drvctl_fileops = { 78 drvctl_read, 79 drvctl_write, 80 drvctl_ioctl, 81 fnullop_fcntl, 82 fnullop_poll, 83 fbadop_stat, 84 drvctl_close, 85 fnullop_kqfilter 86 }; 87 88 #define MAXLOCATORS 100 89 90 static int drvctl_command(struct lwp *, struct plistref *, u_long, int); 91 static int drvctl_getevent(struct lwp *, struct plistref *, u_long, int); 92 93 void 94 drvctl_init(void) 95 { 96 TAILQ_INIT(&drvctl_eventq); 97 mutex_init(&drvctl_lock, MUTEX_DEFAULT, IPL_NONE); 98 cv_init(&drvctl_cond, "devmon"); 99 } 100 101 void 102 devmon_insert(const char *event, prop_dictionary_t ev) 103 { 104 struct drvctl_event *dce, *odce;; 105 106 mutex_enter(&drvctl_lock); 107 108 if (drvctl_nopen == 0) { 109 mutex_exit(&drvctl_lock); 110 return; 111 } 112 113 /* Fill in mandatory member */ 114 if (!prop_dictionary_set_cstring_nocopy(ev, "event", event)) { 115 prop_object_release(ev); 116 mutex_exit(&drvctl_lock); 117 return; 118 } 119 120 dce = kmem_alloc(sizeof(*dce), KM_SLEEP); 121 if (dce == NULL) { 122 mutex_exit(&drvctl_lock); 123 return; 124 } 125 126 dce->dce_event = ev; 127 128 if (drvctl_eventcnt == DRVCTL_EVENTQ_DEPTH) { 129 odce = TAILQ_FIRST(&drvctl_eventq); 130 TAILQ_REMOVE(&drvctl_eventq, odce, dce_link); 131 prop_object_release(odce->dce_event); 132 kmem_free(odce, sizeof(*odce)); 133 --drvctl_eventcnt; 134 } 135 136 TAILQ_INSERT_TAIL(&drvctl_eventq, dce, dce_link); 137 ++drvctl_eventcnt; 138 cv_broadcast(&drvctl_cond); 139 140 mutex_exit(&drvctl_lock); 141 } 142 143 int 144 drvctlopen(dev_t dev, int flags, int mode, struct lwp *l) 145 { 146 struct file *fp; 147 int fd; 148 int ret; 149 150 ret = fd_allocfile(&fp, &fd); 151 if (ret) 152 return (ret); 153 154 /* XXX setup context */ 155 mutex_enter(&drvctl_lock); 156 ret = fd_clone(fp, fd, flags, &drvctl_fileops, /* context */NULL); 157 ++drvctl_nopen; 158 mutex_exit(&drvctl_lock); 159 160 return ret; 161 } 162 163 static int 164 pmdevbyname(int cmd, struct devpmargs *a) 165 { 166 struct device *d; 167 168 if ((d = device_find_by_xname(a->devname)) == NULL) 169 return ENXIO; 170 171 switch (cmd) { 172 case DRVSUSPENDDEV: 173 return pmf_device_recursive_suspend(d, PMF_F_NONE) ? 0 : EBUSY; 174 case DRVRESUMEDEV: 175 if (a->flags & DEVPM_F_SUBTREE) { 176 return pmf_device_resume_subtree(d, PMF_F_NONE) 177 ? 0 : EBUSY; 178 } else { 179 return pmf_device_recursive_resume(d, PMF_F_NONE) 180 ? 0 : EBUSY; 181 } 182 default: 183 return EPASSTHROUGH; 184 } 185 } 186 187 static int 188 listdevbyname(struct devlistargs *l) 189 { 190 device_t d, child; 191 deviter_t di; 192 int cnt = 0, idx, error = 0; 193 194 if ((d = device_find_by_xname(l->l_devname)) == NULL) 195 return ENXIO; 196 197 for (child = deviter_first(&di, 0); child != NULL; 198 child = deviter_next(&di)) { 199 if (device_parent(child) != d) 200 continue; 201 idx = cnt++; 202 if (l->l_childname == NULL || idx >= l->l_children) 203 continue; 204 error = copyoutstr(device_xname(child), l->l_childname[idx], 205 sizeof(l->l_childname[idx]), NULL); 206 if (error != 0) 207 break; 208 } 209 deviter_release(&di); 210 211 l->l_children = cnt; 212 return error; 213 } 214 215 static int 216 detachdevbyname(const char *devname) 217 { 218 struct device *d; 219 220 if ((d = device_find_by_xname(devname)) == NULL) 221 return ENXIO; 222 223 #ifndef XXXFULLRISK 224 /* 225 * If the parent cannot be notified, it might keep 226 * pointers to the detached device. 227 * There might be a private notification mechanism, 228 * but better play save here. 229 */ 230 if (d->dv_parent && !d->dv_parent->dv_cfattach->ca_childdetached) 231 return (ENOTSUP); 232 #endif 233 return (config_detach(d, 0)); 234 } 235 236 static int 237 rescanbus(const char *busname, const char *ifattr, 238 int numlocators, const int *locators) 239 { 240 int i, rc; 241 struct device *d; 242 const struct cfiattrdata * const *ap; 243 244 /* XXX there should be a way to get limits and defaults (per device) 245 from config generated data */ 246 int locs[MAXLOCATORS]; 247 for (i = 0; i < MAXLOCATORS; i++) 248 locs[i] = -1; 249 250 for (i = 0; i < numlocators;i++) 251 locs[i] = locators[i]; 252 253 if ((d = device_find_by_xname(busname)) == NULL) 254 return ENXIO; 255 256 /* 257 * must support rescan, and must have something 258 * to attach to 259 */ 260 if (!d->dv_cfattach->ca_rescan || 261 !d->dv_cfdriver->cd_attrs) 262 return (ENODEV); 263 264 /* allow to omit attribute if there is exactly one */ 265 if (!ifattr) { 266 if (d->dv_cfdriver->cd_attrs[1]) 267 return (EINVAL); 268 ifattr = d->dv_cfdriver->cd_attrs[0]->ci_name; 269 } else { 270 /* check for valid attribute passed */ 271 for (ap = d->dv_cfdriver->cd_attrs; *ap; ap++) 272 if (!strcmp((*ap)->ci_name, ifattr)) 273 break; 274 if (!*ap) 275 return (EINVAL); 276 } 277 278 rc = (*d->dv_cfattach->ca_rescan)(d, ifattr, locs); 279 config_deferred(NULL); 280 return rc; 281 } 282 283 static int 284 drvctl_read(struct file *fp, off_t *offp, struct uio *uio, kauth_cred_t cred, 285 int flags) 286 { 287 return (ENODEV); 288 } 289 290 static int 291 drvctl_write(struct file *fp, off_t *offp, struct uio *uio, kauth_cred_t cred, 292 int flags) 293 { 294 return (ENODEV); 295 } 296 297 static int 298 drvctl_ioctl(struct file *fp, u_long cmd, void *data) 299 { 300 int res; 301 char *ifattr; 302 int *locs; 303 304 switch (cmd) { 305 case DRVSUSPENDDEV: 306 case DRVRESUMEDEV: 307 #define d ((struct devpmargs *)data) 308 res = pmdevbyname(cmd, d); 309 #undef d 310 break; 311 case DRVLISTDEV: 312 res = listdevbyname((struct devlistargs *)data); 313 break; 314 case DRVDETACHDEV: 315 #define d ((struct devdetachargs *)data) 316 res = detachdevbyname(d->devname); 317 #undef d 318 break; 319 case DRVRESCANBUS: 320 #define d ((struct devrescanargs *)data) 321 d->busname[sizeof(d->busname) - 1] = '\0'; 322 323 /* XXX better copyin? */ 324 if (d->ifattr[0]) { 325 d->ifattr[sizeof(d->ifattr) - 1] = '\0'; 326 ifattr = d->ifattr; 327 } else 328 ifattr = 0; 329 330 if (d->numlocators) { 331 if (d->numlocators > MAXLOCATORS) 332 return (EINVAL); 333 locs = malloc(d->numlocators * sizeof(int), M_DEVBUF, 334 M_WAITOK); 335 res = copyin(d->locators, locs, 336 d->numlocators * sizeof(int)); 337 if (res) { 338 free(locs, M_DEVBUF); 339 return (res); 340 } 341 } else 342 locs = 0; 343 res = rescanbus(d->busname, ifattr, d->numlocators, locs); 344 if (locs) 345 free(locs, M_DEVBUF); 346 #undef d 347 break; 348 case DRVCTLCOMMAND: 349 res = drvctl_command(curlwp, (struct plistref *)data, cmd, 350 fp->f_flag); 351 break; 352 case DRVGETEVENT: 353 res = drvctl_getevent(curlwp, (struct plistref *)data, cmd, 354 fp->f_flag); 355 break; 356 default: 357 return (EPASSTHROUGH); 358 } 359 return (res); 360 } 361 362 static int 363 drvctl_close(struct file *fp) 364 { 365 struct drvctl_event *dce; 366 367 /* XXX free context */ 368 mutex_enter(&drvctl_lock); 369 KASSERT(drvctl_nopen > 0); 370 --drvctl_nopen; 371 if (drvctl_nopen == 0) { 372 /* flush queue */ 373 while ((dce = TAILQ_FIRST(&drvctl_eventq)) != NULL) { 374 TAILQ_REMOVE(&drvctl_eventq, dce, dce_link); 375 KASSERT(drvctl_eventcnt > 0); 376 --drvctl_eventcnt; 377 prop_object_release(dce->dce_event); 378 kmem_free(dce, sizeof(*dce)); 379 } 380 } 381 mutex_exit(&drvctl_lock); 382 383 return (0); 384 } 385 386 void 387 drvctlattach(int arg) 388 { 389 } 390 391 /***************************************************************************** 392 * Driver control command processing engine 393 *****************************************************************************/ 394 395 static int 396 drvctl_command_get_properties(struct lwp *l, 397 prop_dictionary_t command_dict, 398 prop_dictionary_t results_dict) 399 { 400 prop_dictionary_t args_dict; 401 prop_string_t devname_string; 402 device_t dev; 403 deviter_t di; 404 405 args_dict = prop_dictionary_get(command_dict, "drvctl-arguments"); 406 if (args_dict == NULL) 407 return (EINVAL); 408 409 devname_string = prop_dictionary_get(args_dict, "device-name"); 410 if (devname_string == NULL) 411 return (EINVAL); 412 413 for (dev = deviter_first(&di, 0); dev != NULL; 414 dev = deviter_next(&di)) { 415 if (prop_string_equals_cstring(devname_string, 416 device_xname(dev))) { 417 prop_dictionary_set(results_dict, "drvctl-result-data", 418 device_properties(dev)); 419 break; 420 } 421 } 422 423 deviter_release(&di); 424 425 if (dev == NULL) 426 return (ESRCH); 427 428 return (0); 429 } 430 431 struct drvctl_command_desc { 432 const char *dcd_name; /* command name */ 433 int (*dcd_func)(struct lwp *, /* handler function */ 434 prop_dictionary_t, 435 prop_dictionary_t); 436 int dcd_rw; /* read or write required */ 437 }; 438 439 static const struct drvctl_command_desc drvctl_command_table[] = { 440 { .dcd_name = "get-properties", 441 .dcd_func = drvctl_command_get_properties, 442 .dcd_rw = FREAD, 443 }, 444 445 { .dcd_name = NULL } 446 }; 447 448 static int 449 drvctl_command(struct lwp *l, struct plistref *pref, u_long ioctl_cmd, 450 int fflag) 451 { 452 prop_dictionary_t command_dict, results_dict; 453 prop_string_t command_string; 454 const struct drvctl_command_desc *dcd; 455 int error; 456 457 error = prop_dictionary_copyin_ioctl(pref, ioctl_cmd, &command_dict); 458 if (error) 459 return (error); 460 461 results_dict = prop_dictionary_create(); 462 if (results_dict == NULL) { 463 prop_object_release(command_dict); 464 return (ENOMEM); 465 } 466 467 command_string = prop_dictionary_get(command_dict, "drvctl-command"); 468 if (command_string == NULL) { 469 error = EINVAL; 470 goto out; 471 } 472 473 for (dcd = drvctl_command_table; dcd->dcd_name != NULL; dcd++) { 474 if (prop_string_equals_cstring(command_string, 475 dcd->dcd_name)) 476 break; 477 } 478 479 if (dcd->dcd_name == NULL) { 480 error = EINVAL; 481 goto out; 482 } 483 484 if ((fflag & dcd->dcd_rw) == 0) { 485 error = EPERM; 486 goto out; 487 } 488 489 error = (*dcd->dcd_func)(l, command_dict, results_dict); 490 491 prop_dictionary_set_int32(results_dict, "drvctl-error", error); 492 493 error = prop_dictionary_copyout_ioctl(pref, ioctl_cmd, results_dict); 494 out: 495 prop_object_release(command_dict); 496 prop_object_release(results_dict); 497 return (error); 498 } 499 500 static int 501 drvctl_getevent(struct lwp *l, struct plistref *pref, u_long ioctl_cmd, 502 int fflag) 503 { 504 struct drvctl_event *dce; 505 int ret; 506 507 if ((fflag & (FREAD|FWRITE)) != (FREAD|FWRITE)) 508 return (EPERM); 509 510 mutex_enter(&drvctl_lock); 511 while ((dce = TAILQ_FIRST(&drvctl_eventq)) == NULL) { 512 if (fflag & O_NONBLOCK) { 513 mutex_exit(&drvctl_lock); 514 return (EWOULDBLOCK); 515 } 516 517 ret = cv_wait_sig(&drvctl_cond, &drvctl_lock); 518 if (ret) { 519 mutex_exit(&drvctl_lock); 520 return (ret); 521 } 522 } 523 TAILQ_REMOVE(&drvctl_eventq, dce, dce_link); 524 KASSERT(drvctl_eventcnt > 0); 525 --drvctl_eventcnt; 526 mutex_exit(&drvctl_lock); 527 528 ret = prop_dictionary_copyout_ioctl(pref, ioctl_cmd, dce->dce_event); 529 530 prop_object_release(dce->dce_event); 531 kmem_free(dce, sizeof(*dce)); 532 533 return (ret); 534 } 535