1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Mike Karels at Berkeley Software Design, Inc. 7 * 8 * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD 9 * project, to make these variables more userfriendly. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94 36 * $FreeBSD: src/sys/kern/kern_sysctl.c,v 1.92.2.9 2003/05/01 22:48:09 trhodes Exp $ 37 */ 38 39 #include "opt_ktrace.h" 40 #include "opt_sysctl.h" 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/kernel.h> 45 #include <sys/buf.h> 46 #include <sys/sysctl.h> 47 #include <sys/malloc.h> 48 #include <sys/proc.h> 49 #include <sys/priv.h> 50 #include <sys/sysmsg.h> 51 #include <sys/lock.h> 52 #include <sys/sbuf.h> 53 #ifdef KTRACE 54 #include <sys/ktrace.h> 55 #endif 56 57 #include <vm/vm.h> 58 #include <vm/vm_extern.h> 59 60 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic"); 61 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids"); 62 63 int sysctl_debugx = 0; 64 SYSCTL_INT(_debug, OID_AUTO, sysctl, CTLFLAG_RW, &sysctl_debugx, 0, ""); 65 66 /* 67 * The sysctllock protects the MIB tree. It also protects sysctl 68 * contexts used with dynamic sysctls. The sysctl_register_oid() and 69 * sysctl_unregister_oid() routines require the sysctllock to already 70 * be held, so the sysctl_lock() and sysctl_unlock() routines are 71 * provided for the few places in the kernel which need to use that 72 * API rather than using the dynamic API. Use of the dynamic API is 73 * strongly encouraged for most code. 74 */ 75 76 static int sysctl_root(SYSCTL_HANDLER_ARGS); 77 static void sysctl_register_oid_int(struct sysctl_oid *oipd); 78 static void sysctl_unregister_oid_int(struct sysctl_oid *oipd); 79 80 struct sysctl_oid_list sysctl__children; /* root list */ 81 82 static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, 83 int recurse); 84 85 static struct sysctl_oid * 86 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list, int lock) 87 { 88 struct sysctl_oid *oidp; 89 90 SLIST_FOREACH(oidp, list, oid_link) { 91 if (strcmp(oidp->oid_name, name) == 0) { 92 break; 93 } 94 } 95 return (oidp); 96 } 97 98 /* 99 * Initialization of the MIB tree. 100 * 101 * Order by number in each list. 102 */ 103 104 void 105 sysctl_register_oid(struct sysctl_oid *oidp) 106 { 107 SYSCTL_XLOCK(); 108 sysctl_register_oid_int(oidp); 109 SYSCTL_XUNLOCK(); 110 } 111 112 static void 113 sysctl_register_oid_int(struct sysctl_oid *oidp) 114 { 115 struct sysctl_oid_list *parent = oidp->oid_parent; 116 struct sysctl_oid *p; 117 struct sysctl_oid *q; 118 119 /* 120 * Finish initialization from sysctl_set or add. 121 */ 122 lockinit(&oidp->oid_lock, "oidlk", 0, LK_CANRECURSE); 123 124 /* 125 * First check if another oid with the same name already 126 * exists in the parent's list. 127 */ 128 p = sysctl_find_oidname(oidp->oid_name, parent, 0); 129 if (p != NULL) { 130 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) 131 p->oid_refcnt++; 132 else 133 kprintf("can't re-use a leaf (%s)!\n", p->oid_name); 134 return; 135 } 136 137 /* 138 * If this oid has a number OID_AUTO, give it a number which 139 * is greater than any current oid. Make sure it is at least 140 * 256 to leave space for pre-assigned oid numbers. 141 */ 142 if (oidp->oid_number == OID_AUTO) { 143 int newoid = 0x100; /* minimum AUTO oid */ 144 145 /* 146 * Adjust based on highest oid in parent list 147 */ 148 SLIST_FOREACH(p, parent, oid_link) { 149 if (newoid <= p->oid_number) 150 newoid = p->oid_number + 1; 151 } 152 oidp->oid_number = newoid; 153 } 154 155 /* 156 * Insert the oid into the parent's list in order. 157 */ 158 q = NULL; 159 SLIST_FOREACH(p, parent, oid_link) { 160 if (oidp->oid_number < p->oid_number) 161 break; 162 q = p; 163 } 164 if (q) 165 SLIST_INSERT_AFTER(q, oidp, oid_link); 166 else 167 SLIST_INSERT_HEAD(parent, oidp, oid_link); 168 } 169 170 void 171 sysctl_unregister_oid(struct sysctl_oid *oidp) 172 { 173 SYSCTL_XLOCK(); 174 sysctl_unregister_oid_int(oidp); 175 SYSCTL_XUNLOCK(); 176 } 177 178 static void 179 sysctl_unregister_oid_int(struct sysctl_oid *oidp) 180 { 181 struct sysctl_oid *p; 182 183 if (oidp->oid_number == OID_AUTO) 184 panic("Trying to unregister OID_AUTO entry: %p", oidp); 185 186 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 187 if (p != oidp) 188 continue; 189 SLIST_REMOVE(oidp->oid_parent, oidp, sysctl_oid, oid_link); 190 return; 191 } 192 193 /* 194 * This can happen when a module fails to register and is 195 * being unloaded afterwards. It should not be a panic() 196 * for normal use. 197 */ 198 kprintf("%s: failed to unregister sysctl\n", __func__); 199 } 200 201 /* Initialize a new context to keep track of dynamically added sysctls. */ 202 int 203 sysctl_ctx_init(struct sysctl_ctx_list *c) 204 { 205 if (c == NULL) 206 return(EINVAL); 207 TAILQ_INIT(c); 208 return(0); 209 } 210 211 /* Free the context, and destroy all dynamic oids registered in this context */ 212 int 213 sysctl_ctx_free(struct sysctl_ctx_list *clist) 214 { 215 struct sysctl_ctx_entry *e, *e1; 216 int error; 217 218 error = 0; 219 /* 220 * First perform a "dry run" to check if it's ok to remove oids. 221 * XXX FIXME 222 * XXX This algorithm is a hack. But I don't know any 223 * XXX better solution for now... 224 */ 225 SYSCTL_XLOCK(); 226 TAILQ_FOREACH(e, clist, link) { 227 error = sysctl_remove_oid_locked(e->entry, 0, 0); 228 if (error) 229 break; 230 } 231 /* 232 * Restore deregistered entries, either from the end, 233 * or from the place where error occured. 234 * e contains the entry that was not unregistered 235 */ 236 if (error) 237 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 238 else 239 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 240 while (e1 != NULL) { 241 sysctl_register_oid(e1->entry); 242 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 243 } 244 if (error) { 245 SYSCTL_XUNLOCK(); 246 return(EBUSY); 247 } 248 /* Now really delete the entries */ 249 e = TAILQ_FIRST(clist); 250 while (e != NULL) { 251 e1 = TAILQ_NEXT(e, link); 252 error = sysctl_remove_oid_locked(e->entry, 1, 0); 253 if (error) 254 panic("sysctl_remove_oid: corrupt tree, entry: %s", 255 e->entry->oid_name); 256 kfree(e, M_SYSCTLOID); 257 e = e1; 258 } 259 SYSCTL_XUNLOCK(); 260 return (error); 261 } 262 263 /* Add an entry to the context */ 264 struct sysctl_ctx_entry * 265 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 266 { 267 struct sysctl_ctx_entry *e; 268 269 SYSCTL_ASSERT_LOCKED(); 270 if (clist == NULL || oidp == NULL) 271 return(NULL); 272 e = kmalloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 273 e->entry = oidp; 274 TAILQ_INSERT_HEAD(clist, e, link); 275 return (e); 276 } 277 278 /* Find an entry in the context */ 279 struct sysctl_ctx_entry * 280 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 281 { 282 struct sysctl_ctx_entry *e; 283 284 SYSCTL_ASSERT_LOCKED(); 285 if (clist == NULL || oidp == NULL) 286 return(NULL); 287 TAILQ_FOREACH(e, clist, link) { 288 if(e->entry == oidp) 289 return(e); 290 } 291 return (e); 292 } 293 294 /* 295 * Delete an entry from the context. 296 * NOTE: this function doesn't free oidp! You have to remove it 297 * with sysctl_remove_oid(). 298 */ 299 int 300 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 301 { 302 struct sysctl_ctx_entry *e; 303 304 if (clist == NULL || oidp == NULL) 305 return (EINVAL); 306 SYSCTL_XLOCK(); 307 e = sysctl_ctx_entry_find(clist, oidp); 308 if (e != NULL) { 309 TAILQ_REMOVE(clist, e, link); 310 SYSCTL_XUNLOCK(); 311 kfree(e, M_SYSCTLOID); 312 return (0); 313 } else { 314 SYSCTL_XUNLOCK(); 315 return (ENOENT); 316 } 317 } 318 319 /* 320 * Remove dynamically created sysctl trees. 321 * oidp - top of the tree to be removed 322 * del - if 0 - just deregister, otherwise free up entries as well 323 * recurse - if != 0 traverse the subtree to be deleted 324 */ 325 int 326 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 327 { 328 int error; 329 330 SYSCTL_XLOCK(); 331 error = sysctl_remove_oid_locked(oidp, del, recurse); 332 SYSCTL_XUNLOCK(); 333 return (error); 334 } 335 336 static int 337 sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse) 338 { 339 struct sysctl_oid *p, *tmp; 340 int error; 341 342 SYSCTL_ASSERT_LOCKED(); 343 if (oidp == NULL) 344 return(EINVAL); 345 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 346 kprintf("can't remove non-dynamic nodes!\n"); 347 return (EINVAL); 348 } 349 /* 350 * WARNING: normal method to do this should be through 351 * sysctl_ctx_free(). Use recursing as the last resort 352 * method to purge your sysctl tree of leftovers... 353 * However, if some other code still references these nodes, 354 * it will panic. 355 */ 356 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 357 if (oidp->oid_refcnt == 1) { 358 SLIST_FOREACH_MUTABLE(p, 359 SYSCTL_CHILDREN(oidp), oid_link, tmp) { 360 if (!recurse) { 361 kprintf("Warning: failed attempt to " 362 "remove oid %s with child %s\n", 363 oidp->oid_name, p->oid_name); 364 return (ENOTEMPTY); 365 } 366 error = sysctl_remove_oid_locked(p, del, 367 recurse); 368 if (error) 369 return (error); 370 } 371 if (del) 372 kfree(SYSCTL_CHILDREN(oidp), M_SYSCTLOID); 373 } 374 } 375 if (oidp->oid_refcnt > 1 ) { 376 oidp->oid_refcnt--; 377 } else { 378 if (oidp->oid_refcnt == 0) { 379 kprintf("Warning: bad oid_refcnt=%u (%s)!\n", 380 oidp->oid_refcnt, oidp->oid_name); 381 return (EINVAL); 382 } 383 sysctl_unregister_oid(oidp); 384 if (del) { 385 /* 386 * Wait for all threads running the handler to drain. 387 * This preserves the previous behavior when the 388 * sysctl lock was held across a handler invocation, 389 * and is necessary for module unload correctness. 390 */ 391 while (oidp->oid_running > 0) { 392 oidp->oid_kind |= CTLFLAG_DYING; 393 tsleep_interlock(&oidp->oid_running, 0); 394 SYSCTL_XUNLOCK(); 395 tsleep(&oidp->oid_running, PINTERLOCKED, 396 "oidrm", 0); 397 SYSCTL_XLOCK(); 398 } 399 if (oidp->oid_descr) 400 kfree(__DECONST(char *, oidp->oid_descr), 401 M_SYSCTLOID); 402 kfree(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); 403 lockuninit(&oidp->oid_lock); 404 kfree(oidp, M_SYSCTLOID); 405 } 406 } 407 return (0); 408 } 409 410 int 411 sysctl_remove_name(struct sysctl_oid *parent, const char *name, 412 int del, int recurse) 413 { 414 struct sysctl_oid *p, *tmp; 415 int error; 416 417 error = ENOENT; 418 SYSCTL_XLOCK(); 419 SLIST_FOREACH_MUTABLE(p, SYSCTL_CHILDREN(parent), oid_link, tmp) { 420 if (strcmp(p->oid_name, name) == 0) { 421 error = sysctl_remove_oid_locked(p, del, recurse); 422 break; 423 } 424 } 425 SYSCTL_XUNLOCK(); 426 427 return (error); 428 } 429 430 /* 431 * Create new sysctls at run time. 432 * clist may point to a valid context initialized with sysctl_ctx_init(). 433 */ 434 struct sysctl_oid * 435 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 436 int number, const char *name, int kind, void *arg1, int arg2, 437 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr) 438 { 439 struct sysctl_oid *oidp; 440 ssize_t len; 441 char *newname; 442 443 /* You have to hook up somewhere.. */ 444 if (parent == NULL) 445 return(NULL); 446 SYSCTL_XLOCK(); 447 /* Check if the node already exists, otherwise create it */ 448 oidp = sysctl_find_oidname(name, parent, 0); 449 if (oidp != NULL) { 450 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 451 oidp->oid_refcnt++; 452 /* Update the context */ 453 if (clist != NULL) 454 sysctl_ctx_entry_add(clist, oidp); 455 SYSCTL_XUNLOCK(); 456 return (oidp); 457 } else { 458 kprintf("can't re-use a leaf (%s)!\n", name); 459 SYSCTL_XUNLOCK(); 460 return (NULL); 461 } 462 } 463 oidp = kmalloc(sizeof(struct sysctl_oid), M_SYSCTLOID, 464 M_WAITOK | M_ZERO); 465 oidp->oid_parent = parent; 466 SLIST_NEXT(oidp, oid_link) = NULL; 467 oidp->oid_number = number; 468 oidp->oid_refcnt = 1; 469 len = strlen(name); 470 newname = kmalloc(len + 1, M_SYSCTLOID, M_WAITOK); 471 bcopy(name, newname, len + 1); 472 newname[len] = '\0'; 473 oidp->oid_name = newname; 474 oidp->oid_handler = handler; 475 oidp->oid_kind = CTLFLAG_DYN | kind; 476 if ((kind & CTLTYPE) == CTLTYPE_NODE) { 477 struct sysctl_oid_list *children; 478 479 /* Allocate space for children */ 480 children = kmalloc(sizeof(*children), M_SYSCTLOID, M_WAITOK); 481 SYSCTL_SET_CHILDREN(oidp, children); 482 SLIST_INIT(children); 483 } else { 484 oidp->oid_arg1 = arg1; 485 oidp->oid_arg2 = arg2; 486 } 487 oidp->oid_fmt = fmt; 488 if (descr) { 489 int len = strlen(descr) + 1; 490 oidp->oid_descr = kmalloc(len, M_SYSCTLOID, M_WAITOK); 491 strcpy((char *)(uintptr_t)(const void *)oidp->oid_descr, descr); 492 }; 493 /* Update the context, if used */ 494 if (clist != NULL) 495 sysctl_ctx_entry_add(clist, oidp); 496 /* Register this oid */ 497 sysctl_register_oid_int(oidp); 498 SYSCTL_XUNLOCK(); 499 return (oidp); 500 } 501 502 /* 503 * Rename an existing oid. 504 */ 505 void 506 sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) 507 { 508 char *newname; 509 char *oldname; 510 511 newname = kstrdup(name, M_SYSCTLOID); 512 SYSCTL_XLOCK(); 513 oldname = __DECONST(char *, oidp->oid_name); 514 oidp->oid_name = newname; 515 SYSCTL_XUNLOCK(); 516 kfree(oldname, M_SYSCTLOID); 517 } 518 519 /* 520 * Register the kernel's oids on startup. 521 */ 522 SET_DECLARE(sysctl_set, struct sysctl_oid); 523 524 static void 525 sysctl_register_all(void *arg) 526 { 527 struct sysctl_oid **oidp; 528 529 SYSCTL_XLOCK(); 530 SET_FOREACH(oidp, sysctl_set) 531 sysctl_register_oid(*oidp); 532 SYSCTL_XUNLOCK(); 533 } 534 SYSINIT(sysctl, SI_BOOT1_POST, SI_ORDER_ANY, sysctl_register_all, 0); 535 536 #ifdef SYSCTL_DEBUG 537 /* 538 * "Staff-functions" 539 * 540 * These functions implement a presently undocumented interface 541 * used by the sysctl program to walk the tree, and get the type 542 * so it can print the value. 543 * This interface is under work and consideration, and should probably 544 * be killed with a big axe by the first person who can find the time. 545 * (be aware though, that the proper interface isn't as obvious as it 546 * may seem, there are various conflicting requirements. 547 * 548 * {CTL_SYSCTL, CTL_SYSCTL_DEBUG} kprintf the entire MIB-tree. 549 * {CTL_SYSCTL, CTL_SYSCTL_NAME, ...} return the name of the "..." 550 * OID. 551 * {CTL_SYSCTL, CTL_SYSCTL_NEXT, ...} return the next OID. 552 * {CTL_SYSCTL, CTL_SYSCTL_NAME2OID} return the OID of the name in 553 * "new" 554 * {CTL_SYSCTL, CTL_SYSCTL_OIDFMT, ...} return the kind & format info 555 * for the "..." OID. 556 * {CTL_SYSCTL, CTL_SYSCTL_OIDDESCR, ...} return the description of the 557 * "..." OID. 558 */ 559 560 static void 561 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 562 { 563 int k; 564 struct sysctl_oid *oidp; 565 566 SLIST_FOREACH(oidp, l, oid_link) { 567 568 for (k=0; k<i; k++) 569 kprintf(" "); 570 571 kprintf("%d %s ", oidp->oid_number, oidp->oid_name); 572 573 kprintf("%c%c", 574 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 575 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 576 577 if (oidp->oid_handler) 578 kprintf(" *Handler"); 579 580 switch (oidp->oid_kind & CTLTYPE) { 581 case CTLTYPE_NODE: 582 kprintf(" Node\n"); 583 if (!oidp->oid_handler) { 584 sysctl_sysctl_debug_dump_node( 585 oidp->oid_arg1, i+2); 586 } 587 break; 588 case CTLTYPE_INT: 589 kprintf(" Int\n"); 590 break; 591 case CTLTYPE_UINT: 592 kprintf(" u_int\n"); 593 break; 594 case CTLTYPE_LONG: 595 kprintf(" Long\n"); 596 break; 597 case CTLTYPE_ULONG: 598 kprintf(" u_long\n"); 599 break; 600 case CTLTYPE_STRING: 601 kprintf(" String\n"); 602 break; 603 case CTLTYPE_S8: 604 kprintf(" int8_t\n"); 605 break; 606 case CTLTYPE_S16: 607 kprintf(" int16_t\n"); 608 break; 609 case CTLTYPE_S32: 610 kprintf(" int32_t\n"); 611 break; 612 case CTLTYPE_S64: 613 kprintf(" int64_t\n"); 614 break; 615 case CTLTYPE_U8: 616 kprintf(" uint8_t\n"); 617 break; 618 case CTLTYPE_U16: 619 kprintf(" uint16_t\n"); 620 break; 621 case CTLTYPE_U32: 622 kprintf(" uint32_t\n"); 623 break; 624 case CTLTYPE_U64: 625 kprintf(" uint64_t\n"); 626 break; 627 case CTLTYPE_BIT32(0): 628 kprintf(" Int\n"); 629 break; 630 case CTLTYPE_BIT64(0): 631 kprintf(" Int\n"); 632 break; 633 case CTLTYPE_OPAQUE: 634 kprintf(" Opaque/struct\n"); 635 break; 636 default: 637 kprintf("\n"); 638 break; 639 } 640 641 } 642 } 643 644 static int 645 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 646 { 647 int error; 648 649 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 650 if (error) 651 return (error); 652 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 653 654 return (ENOENT); 655 } 656 657 SYSCTL_PROC(_sysctl, CTL_SYSCTL_DEBUG, debug, CTLTYPE_STRING | CTLFLAG_RD, 658 0, 0, sysctl_sysctl_debug, "-", ""); 659 #endif /* SYSCTL_DEBUG */ 660 661 static int 662 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 663 { 664 int *name = (int *) arg1; 665 u_int namelen = arg2; 666 int error = 0; 667 struct sysctl_oid *oid; 668 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 669 char buf[10]; 670 671 while (namelen) { 672 if (!lsp) { 673 ksnprintf(buf, sizeof(buf), "%d", *name); 674 if (req->oldidx) 675 error = SYSCTL_OUT(req, ".", 1); 676 if (!error) 677 error = SYSCTL_OUT(req, buf, strlen(buf)); 678 if (error) 679 goto out; 680 namelen--; 681 name++; 682 continue; 683 } 684 lsp2 = NULL; 685 SLIST_FOREACH(oid, lsp, oid_link) { 686 if (oid->oid_number != *name) 687 continue; 688 689 if (req->oldidx) 690 error = SYSCTL_OUT(req, ".", 1); 691 if (!error) 692 error = SYSCTL_OUT(req, oid->oid_name, 693 strlen(oid->oid_name)); 694 if (error) 695 goto out; 696 697 namelen--; 698 name++; 699 700 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 701 break; 702 703 if (oid->oid_handler) 704 break; 705 706 lsp2 = SYSCTL_CHILDREN(oid); 707 break; 708 } 709 lsp = lsp2; 710 } 711 error = SYSCTL_OUT(req, "", 1); 712 out: 713 return (error); 714 } 715 716 SYSCTL_NODE(_sysctl, CTL_SYSCTL_NAME, name, CTLFLAG_RD | CTLFLAG_NOLOCK, 717 sysctl_sysctl_name, ""); 718 719 static int 720 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 721 int *next, int *len, int level, struct sysctl_oid **oidpp) 722 { 723 struct sysctl_oid *oidp; 724 725 *len = level; 726 SLIST_FOREACH(oidp, lsp, oid_link) { 727 *next = oidp->oid_number; 728 *oidpp = oidp; 729 730 if (oidp->oid_kind & CTLFLAG_SKIP) 731 continue; 732 733 if (!namelen) { 734 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 735 return (0); 736 if (oidp->oid_handler) 737 /* We really should call the handler here...*/ 738 return (0); 739 lsp = SYSCTL_CHILDREN(oidp); 740 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 741 len, level+1, oidpp)) 742 return (0); 743 goto emptynode; 744 } 745 746 if (oidp->oid_number < *name) 747 continue; 748 749 if (oidp->oid_number > *name) { 750 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 751 return (0); 752 if (oidp->oid_handler) 753 return (0); 754 lsp = SYSCTL_CHILDREN(oidp); 755 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 756 next+1, len, level+1, oidpp)) 757 return (0); 758 goto next; 759 } 760 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 761 continue; 762 763 if (oidp->oid_handler) 764 continue; 765 766 lsp = SYSCTL_CHILDREN(oidp); 767 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 768 len, level+1, oidpp)) 769 return (0); 770 next: 771 namelen = 1; 772 emptynode: 773 *len = level; 774 } 775 return (1); 776 } 777 778 static int 779 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 780 { 781 int *name = (int *) arg1; 782 u_int namelen = arg2; 783 int i, j, error; 784 struct sysctl_oid *oid; 785 struct sysctl_oid_list *lsp = &sysctl__children; 786 int newoid[CTL_MAXNAME]; 787 788 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 789 if (i) 790 return ENOENT; 791 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 792 793 return (error); 794 } 795 796 SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXT, next, CTLFLAG_RD | CTLFLAG_NOLOCK, 797 sysctl_sysctl_next, ""); 798 799 static int 800 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) 801 { 802 struct sysctl_oid *oidp; 803 struct sysctl_oid_list *lsp = &sysctl__children; 804 char *p; 805 806 SYSCTL_ASSERT_LOCKED(); 807 808 for (*len = 0; *len < CTL_MAXNAME;) { 809 p = strsep(&name, "."); 810 811 oidp = SLIST_FIRST(lsp); 812 for (;; oidp = SLIST_NEXT(oidp, oid_link)) { 813 if (oidp == NULL) 814 return (ENOENT); 815 if (strcmp(p, oidp->oid_name) == 0) 816 break; 817 } 818 *oid++ = oidp->oid_number; 819 (*len)++; 820 821 if (name == NULL || *name == '\0') { 822 if (oidpp) 823 *oidpp = oidp; 824 return (0); 825 } 826 827 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 828 break; 829 830 if (oidp->oid_handler) 831 break; 832 833 lsp = SYSCTL_CHILDREN(oidp); 834 } 835 return (ENOENT); 836 } 837 838 static int 839 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 840 { 841 char *p; 842 int error, oid[CTL_MAXNAME], len; 843 struct sysctl_oid *op = NULL; 844 845 if (!req->newlen) 846 return ENOENT; 847 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 848 return (ENAMETOOLONG); 849 850 p = kmalloc(req->newlen+1, M_SYSCTL, M_WAITOK); 851 852 error = SYSCTL_IN(req, p, req->newlen); 853 if (error) { 854 kfree(p, M_SYSCTL); 855 return (error); 856 } 857 858 p [req->newlen] = '\0'; 859 860 error = name2oid(p, oid, &len, &op); 861 862 kfree(p, M_SYSCTL); 863 864 if (error) 865 return (error); 866 867 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 868 return (error); 869 } 870 871 SYSCTL_PROC(_sysctl, CTL_SYSCTL_NAME2OID, name2oid, 872 CTLFLAG_RW | CTLFLAG_ANYBODY | CTLFLAG_NOLOCK, 873 0, 0, sysctl_sysctl_name2oid, "I", ""); 874 875 static int 876 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 877 { 878 struct sysctl_oid *oid; 879 int error; 880 881 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 882 if (error) 883 return (error); 884 885 if (!oid->oid_fmt) 886 return (ENOENT); 887 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 888 if (error) 889 return (error); 890 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 891 return (error); 892 } 893 894 895 SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDFMT, oidfmt, CTLFLAG_RD | CTLFLAG_NOLOCK, 896 sysctl_sysctl_oidfmt, ""); 897 898 static int 899 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 900 { 901 struct sysctl_oid *oid; 902 int error; 903 904 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 905 if (error) 906 return (error); 907 908 if (!oid->oid_descr) 909 return (ENOENT); 910 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 911 return (error); 912 } 913 914 SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDDESCR, oiddescr, 915 CTLFLAG_RD | CTLFLAG_NOLOCK, 916 sysctl_sysctl_oiddescr, ""); 917 918 /* 919 * Default "handler" functions. 920 */ 921 922 /* 923 * Handle an 8-bit number, signed or unsigned. arg1 points to it. 924 */ 925 926 int 927 sysctl_handle_8(SYSCTL_HANDLER_ARGS) 928 { 929 int error = 0; 930 931 if (!arg1) 932 return (EINVAL); 933 error = SYSCTL_OUT(req, arg1, sizeof(int8_t)); 934 935 if (error || !req->newptr) 936 return (error); 937 938 error = SYSCTL_IN(req, arg1, sizeof(int8_t)); 939 return (error); 940 } 941 942 /* 943 * Handle a 16-bit number, signed or unsigned. arg1 points to it. 944 */ 945 946 int 947 sysctl_handle_16(SYSCTL_HANDLER_ARGS) 948 { 949 int error = 0; 950 951 if (!arg1) 952 return (EINVAL); 953 error = SYSCTL_OUT(req, arg1, sizeof(int16_t)); 954 955 if (error || !req->newptr) 956 return (error); 957 958 error = SYSCTL_IN(req, arg1, sizeof(int16_t)); 959 return (error); 960 } 961 962 /* 963 * Handle a 32-bit number, signed or unsigned. arg1 points to it. 964 */ 965 966 int 967 sysctl_handle_32(SYSCTL_HANDLER_ARGS) 968 { 969 int error = 0; 970 971 if (!arg1) 972 return (EINVAL); 973 error = SYSCTL_OUT(req, arg1, sizeof(int32_t)); 974 975 if (error || !req->newptr) 976 return (error); 977 978 error = SYSCTL_IN(req, arg1, sizeof(int32_t)); 979 return (error); 980 } 981 982 /* 983 * Handle a 64-bit number, signed or unsigned. arg1 points to it. 984 */ 985 986 int 987 sysctl_handle_64(SYSCTL_HANDLER_ARGS) 988 { 989 int error = 0; 990 991 if (!arg1) 992 return (EINVAL); 993 error = SYSCTL_OUT(req, arg1, sizeof(int64_t)); 994 995 if (error || !req->newptr) 996 return (error); 997 998 error = SYSCTL_IN(req, arg1, sizeof(int64_t)); 999 return (error); 1000 } 1001 1002 /* 1003 * Handle an int, signed or unsigned. 1004 * Two cases: 1005 * a variable: point arg1 at it. 1006 * a constant: pass it in arg2. 1007 */ 1008 1009 int 1010 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 1011 { 1012 int error = 0; 1013 1014 if (arg1) 1015 error = SYSCTL_OUT(req, arg1, sizeof(int)); 1016 else 1017 error = SYSCTL_OUT(req, &arg2, sizeof(int)); 1018 1019 if (error || !req->newptr) 1020 return (error); 1021 1022 if (!arg1) 1023 error = EPERM; 1024 else 1025 error = SYSCTL_IN(req, arg1, sizeof(int)); 1026 return (error); 1027 } 1028 1029 /* 1030 * Handle a long, signed or unsigned. arg1 points to it. 1031 */ 1032 1033 int 1034 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 1035 { 1036 int error = 0; 1037 1038 if (!arg1) 1039 return (EINVAL); 1040 if (req->oldlen == sizeof(int) && 1041 *(long *)arg1 >= INT_MIN && 1042 *(long *)arg1 <= INT_MAX) { 1043 /* 1044 * Backwards compatibility for read-only fields promoted 1045 * from int to long. Allow userland to request the field 1046 * as an integer if the value is in-range. 1047 */ 1048 int val = (int)*(long *)arg1; 1049 error = SYSCTL_OUT(req, &val, sizeof(int)); 1050 } else { 1051 /* 1052 * Normal operation fo a long 1053 */ 1054 error = SYSCTL_OUT(req, arg1, sizeof(long)); 1055 } 1056 1057 if (error || !req->newptr) 1058 return (error); 1059 1060 error = SYSCTL_IN(req, arg1, sizeof(long)); 1061 1062 return (error); 1063 } 1064 1065 /* 1066 * Handle a quad, signed or unsigned. arg1 points to it. 1067 */ 1068 1069 int 1070 sysctl_handle_quad(SYSCTL_HANDLER_ARGS) 1071 { 1072 int error = 0; 1073 1074 if (!arg1) 1075 return (EINVAL); 1076 error = SYSCTL_OUT(req, arg1, sizeof(quad_t)); 1077 1078 if (error || !req->newptr) 1079 return (error); 1080 1081 error = SYSCTL_IN(req, arg1, sizeof(quad_t)); 1082 return (error); 1083 } 1084 1085 /* 1086 * Handle an bit in a 32-bit field, pass and return an 'int' 1087 * Two cases: 1088 * a variable: point arg1 at it. 1089 * a constant: pass it in arg2. 1090 */ 1091 1092 int 1093 sysctl_handle_bit32(SYSCTL_HANDLER_ARGS) 1094 { 1095 int error = 0; 1096 uint32_t mask; 1097 int v; 1098 int bit; 1099 1100 bit = (oidp->oid_kind & CTLMASK_BITFLD) >> CTLSHIFT_BITFLD; 1101 mask = arg1 ? *(uint32_t *)arg1 : (uint32_t)arg2; 1102 v = (mask & (1U << bit)) ? 1 : 0; 1103 error = SYSCTL_OUT(req, &v, sizeof(int)); 1104 1105 if (error || !req->newptr) 1106 return (error); 1107 1108 if (!arg1) { 1109 error = EPERM; 1110 } else { 1111 error = SYSCTL_IN(req, &v, sizeof(int)); 1112 if (error == 0) { 1113 if (v) 1114 atomic_set_int((uint32_t *)arg1, 1U << bit); 1115 else 1116 atomic_clear_int((uint32_t *)arg1, 1U << bit); 1117 } 1118 } 1119 return (error); 1120 } 1121 1122 /* 1123 * Handle an bit in a 64-bit field, pass and return an 'int' 1124 * Two cases: 1125 * a variable: point arg1 at it. 1126 * a constant: pass it in arg2. (NOTE: arg2 is only 32bits) 1127 */ 1128 1129 int 1130 sysctl_handle_bit64(SYSCTL_HANDLER_ARGS) 1131 { 1132 int error = 0; 1133 uint64_t mask; 1134 int v; 1135 int bit; 1136 1137 bit = (oidp->oid_kind & CTLMASK_BITFLD) >> CTLSHIFT_BITFLD; 1138 mask = arg1 ? *(uint64_t *)arg1 : (uint64_t)(uint32_t)arg2; 1139 v = (mask & (1LU << bit)) ? 1 : 0; 1140 error = SYSCTL_OUT(req, &v, sizeof(int)); 1141 1142 if (error || !req->newptr) 1143 return (error); 1144 1145 if (!arg1) { 1146 error = EPERM; 1147 } else { 1148 error = SYSCTL_IN(req, &v, sizeof(int)); 1149 if (error == 0) { 1150 if (v) 1151 atomic_set_long((uint64_t *)arg1, 1LU << bit); 1152 else 1153 atomic_clear_long((uint64_t *)arg1, 1LU << bit); 1154 } 1155 } 1156 return (error); 1157 } 1158 1159 /* 1160 * Handle our generic '\0' terminated 'C' string. 1161 * Two cases: 1162 * a variable string: point arg1 at it, arg2 is max length. 1163 * a constant string: point arg1 at it, arg2 is zero. 1164 */ 1165 1166 int 1167 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 1168 { 1169 int error=0; 1170 1171 error = SYSCTL_OUT(req, arg1, strlen((char *)arg1)+1); 1172 1173 if (error || !req->newptr) 1174 return (error); 1175 1176 if ((req->newlen - req->newidx) >= arg2) { 1177 error = EINVAL; 1178 } else { 1179 arg2 = (req->newlen - req->newidx); 1180 error = SYSCTL_IN(req, arg1, arg2); 1181 ((char *)arg1)[arg2] = '\0'; 1182 } 1183 1184 return (error); 1185 } 1186 1187 /* 1188 * Handle any kind of opaque data. 1189 * arg1 points to it, arg2 is the size. 1190 */ 1191 1192 int 1193 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 1194 { 1195 int error; 1196 1197 error = SYSCTL_OUT(req, arg1, arg2); 1198 1199 if (error || !req->newptr) 1200 return (error); 1201 1202 error = SYSCTL_IN(req, arg1, arg2); 1203 1204 return (error); 1205 } 1206 1207 /* 1208 * Transfer functions to/from kernel space. 1209 * XXX: rather untested at this point 1210 */ 1211 static int 1212 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 1213 { 1214 size_t i = 0; 1215 1216 if (req->oldptr) { 1217 i = l; 1218 if (i > req->oldlen - req->oldidx) 1219 i = req->oldlen - req->oldidx; 1220 if (i > 0) 1221 bcopy(p, (char *)req->oldptr + req->oldidx, i); 1222 } 1223 req->oldidx += l; 1224 if (req->oldptr && i != l) 1225 return (ENOMEM); 1226 return (0); 1227 } 1228 1229 static int 1230 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 1231 { 1232 1233 if (!req->newptr) 1234 return 0; 1235 if (req->newlen - req->newidx < l) 1236 return (EINVAL); 1237 bcopy((char *)req->newptr + req->newidx, p, l); 1238 req->newidx += l; 1239 return (0); 1240 } 1241 1242 int 1243 kernel_sysctl(int *name, u_int namelen, 1244 void *old, size_t *oldlenp, 1245 void *new, size_t newlen, size_t *retval) 1246 { 1247 int error = 0; 1248 struct sysctl_req req; 1249 1250 bzero(&req, sizeof req); 1251 1252 req.td = curthread; 1253 1254 if (oldlenp) { 1255 req.oldlen = *oldlenp; 1256 } 1257 req.validlen = req.oldlen; 1258 1259 if (old) { 1260 req.oldptr= old; 1261 } 1262 1263 if (new != NULL) { 1264 req.newlen = newlen; 1265 req.newptr = new; 1266 } 1267 1268 req.oldfunc = sysctl_old_kernel; 1269 req.newfunc = sysctl_new_kernel; 1270 #if 0 1271 req.lock = REQ_UNWIRED; 1272 #endif 1273 1274 SYSCTL_SLOCK(); 1275 error = sysctl_root(0, name, namelen, &req); 1276 SYSCTL_SUNLOCK(); 1277 1278 #if 0 1279 if (req.lock == REQ_WIRED && req.validlen > 0) 1280 vsunlock(req.oldptr, req.validlen); 1281 #endif 1282 1283 if (error && error != ENOMEM) 1284 return (error); 1285 1286 if (retval) { 1287 if (req.oldptr && req.oldidx > req.validlen) 1288 *retval = req.validlen; 1289 else 1290 *retval = req.oldidx; 1291 } 1292 return (error); 1293 } 1294 1295 int 1296 kernel_sysctlbyname(char *name, 1297 void *old, size_t *oldlenp, 1298 void *new, size_t newlen, size_t *retval) 1299 { 1300 int oid[CTL_MAXNAME]; 1301 size_t oidlen, plen; 1302 int error; 1303 1304 oid[0] = CTL_SYSCTL; 1305 oid[1] = CTL_SYSCTL_NAME2OID; 1306 oidlen = sizeof(oid); 1307 1308 error = kernel_sysctl(oid, 2, oid, &oidlen, name, strlen(name), &plen); 1309 if (error) 1310 return (error); 1311 1312 error = kernel_sysctl(oid, plen / sizeof(int), old, oldlenp, 1313 new, newlen, retval); 1314 return (error); 1315 } 1316 1317 /* 1318 * Transfer function to/from user space. 1319 */ 1320 static int 1321 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1322 { 1323 int error = 0; 1324 size_t i = 0; 1325 1326 #if 0 1327 if (req->lock == 1 && req->oldptr) { 1328 vslock(req->oldptr, req->oldlen); 1329 req->lock = 2; 1330 } 1331 #endif 1332 if (req->oldptr) { 1333 i = l; 1334 if (i > req->oldlen - req->oldidx) 1335 i = req->oldlen - req->oldidx; 1336 if (i > 0) 1337 error = copyout(p, (char *)req->oldptr + req->oldidx, 1338 i); 1339 } 1340 req->oldidx += l; 1341 if (error) 1342 return (error); 1343 if (req->oldptr && i < l) 1344 return (ENOMEM); 1345 return (0); 1346 } 1347 1348 static int 1349 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1350 { 1351 int error; 1352 1353 if (!req->newptr) 1354 return 0; 1355 if (req->newlen - req->newidx < l) 1356 return (EINVAL); 1357 error = copyin((char *)req->newptr + req->newidx, p, l); 1358 req->newidx += l; 1359 return (error); 1360 } 1361 1362 int 1363 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 1364 int *nindx, struct sysctl_req *req) 1365 { 1366 struct sysctl_oid_list *lsp; 1367 struct sysctl_oid *oid; 1368 int indx; 1369 1370 lsp = &sysctl__children; 1371 indx = 0; 1372 while (indx < CTL_MAXNAME) { 1373 SLIST_FOREACH(oid, lsp, oid_link) { 1374 if (oid->oid_number == name[indx]) 1375 break; 1376 } 1377 if (oid == NULL) 1378 return (ENOENT); 1379 1380 indx++; 1381 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1382 if (oid->oid_handler != NULL || indx == namelen) { 1383 *noid = oid; 1384 if (nindx != NULL) 1385 *nindx = indx; 1386 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 1387 ("%s found DYING node %p", __func__, oid)); 1388 return (0); 1389 } 1390 lsp = SYSCTL_CHILDREN(oid); 1391 } else if (indx == namelen) { 1392 *noid = oid; 1393 if (nindx != NULL) 1394 *nindx = indx; 1395 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 1396 ("%s found DYING node %p", __func__, oid)); 1397 return (0); 1398 } else { 1399 return (ENOTDIR); 1400 } 1401 } 1402 return (ENOENT); 1403 } 1404 1405 /* 1406 * Traverse our tree, and find the right node, execute whatever it points 1407 * to, and return the resulting error code. 1408 */ 1409 static int 1410 sysctl_root(SYSCTL_HANDLER_ARGS) 1411 { 1412 struct thread *td = req->td; 1413 struct proc *p = td ? td->td_proc : NULL; 1414 struct sysctl_oid *oid; 1415 int error, indx; 1416 int lktype; 1417 1418 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 1419 if (error) 1420 return (error); 1421 1422 if (sysctl_debugx & 1) { 1423 kprintf("pid %d oid %p %s\n", 1424 (p ? p->p_pid : -1), oid, oid->oid_name); 1425 } 1426 1427 1428 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1429 /* 1430 * You can't call a sysctl when it's a node, but has 1431 * no handler. Inform the user that it's a node. 1432 * The indx may or may not be the same as namelen. 1433 */ 1434 if (oid->oid_handler == NULL) 1435 return (EISDIR); 1436 } 1437 1438 /* If writing isn't allowed */ 1439 if (req->newptr && (!(oid->oid_kind & CTLFLAG_WR) || 1440 ((oid->oid_kind & CTLFLAG_SECURE) && securelevel > 0))) 1441 return (EPERM); 1442 1443 /* Most likely only root can write */ 1444 if (!(oid->oid_kind & CTLFLAG_ANYBODY) && req->newptr && p && 1445 (error = priv_check_cred(td->td_ucred, 1446 (oid->oid_kind & CTLFLAG_PRISON) ? PRIV_SYSCTL_WRITEJAIL : 1447 PRIV_SYSCTL_WRITE, 0))) 1448 return (error); 1449 1450 if (oid->oid_handler == NULL) 1451 return EINVAL; 1452 1453 /* 1454 * Default oid locking is exclusive when modifying (newptr), 1455 * shared otherwise, unless overridden with a control flag. 1456 */ 1457 if ((oid->oid_kind & CTLFLAG_NOLOCK) == 0) { 1458 lktype = (req->newptr != NULL) ? LK_EXCLUSIVE : LK_SHARED; 1459 if (oid->oid_kind & CTLFLAG_SHLOCK) 1460 lktype = LK_SHARED; 1461 if (oid->oid_kind & CTLFLAG_EXLOCK) 1462 lktype = LK_EXCLUSIVE; 1463 #if 1 1464 lockmgr(&oid->oid_lock, lktype); 1465 #else 1466 /* DEBUGGING */ 1467 if (lockmgr(&oid->oid_lock, lktype | LK_SLEEPFAIL)) { 1468 kprintf("%s\n", oid->oid_name); 1469 lockmgr(&oid->oid_lock, lktype); 1470 } 1471 #endif 1472 } 1473 1474 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) 1475 error = oid->oid_handler(oid, (int *)arg1 + indx, arg2 - indx, 1476 req); 1477 else 1478 error = oid->oid_handler(oid, oid->oid_arg1, oid->oid_arg2, 1479 req); 1480 1481 if ((oid->oid_kind & CTLFLAG_NOLOCK) == 0) 1482 lockmgr(&oid->oid_lock, LK_RELEASE); 1483 return (error); 1484 } 1485 1486 int 1487 sys___sysctl(struct sysmsg *sysmsg, const struct sysctl_args *uap) 1488 { 1489 int error, i, name[CTL_MAXNAME]; 1490 size_t j; 1491 1492 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 1493 return (EINVAL); 1494 1495 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 1496 if (error) 1497 return (error); 1498 1499 error = userland_sysctl(name, uap->namelen, 1500 uap->old, uap->oldlenp, 0, 1501 uap->new, uap->newlen, &j); 1502 if (error && error != ENOMEM) 1503 return (error); 1504 if (uap->oldlenp) { 1505 i = copyout(&j, uap->oldlenp, sizeof(j)); 1506 if (i) 1507 return (i); 1508 } 1509 return (error); 1510 } 1511 1512 /* 1513 * This is used from various compatibility syscalls too. That's why name 1514 * must be in kernel space. 1515 */ 1516 int 1517 userland_sysctl(int *name, u_int namelen, 1518 void *old, size_t *oldlenp, int inkernel, 1519 void *new, size_t newlen, size_t *retval) 1520 { 1521 struct thread *td = curthread; 1522 struct lwp *lp = td->td_lwp; 1523 int error = 0; 1524 struct sysctl_req req; 1525 1526 bzero(&req, sizeof req); 1527 1528 req.td = td; 1529 req.flags = 0; 1530 1531 if (oldlenp) { 1532 if (inkernel) { 1533 req.oldlen = *oldlenp; 1534 } else { 1535 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 1536 if (error) 1537 return (error); 1538 } 1539 } 1540 req.validlen = req.oldlen; 1541 1542 /* 1543 * NOTE: User supplied buffers are not guaranteed to be good, 1544 * the sysctl copyins and copyouts can fail. 1545 */ 1546 if (old) 1547 req.oldptr= old; 1548 1549 if (new != NULL) { 1550 req.newlen = newlen; 1551 req.newptr = new; 1552 } 1553 1554 req.oldfunc = sysctl_old_user; 1555 req.newfunc = sysctl_new_user; 1556 #if 0 1557 req.lock = REQ_UNWIRED; 1558 #endif 1559 1560 #ifdef KTRACE 1561 if (KTRPOINT(td, KTR_SYSCTL)) 1562 ktrsysctl(lp, name, namelen); 1563 #endif 1564 1565 for (;;) { 1566 req.oldidx = 0; 1567 req.newidx = 0; 1568 SYSCTL_SLOCK(); 1569 error = sysctl_root(0, name, namelen, &req); 1570 SYSCTL_SUNLOCK(); 1571 if (error != EAGAIN) 1572 break; 1573 lwkt_yield(); 1574 } 1575 1576 #if 0 1577 if (req.lock == REQ_WIRED && req.validlen > 0) 1578 vsunlock(req.oldptr, req.validlen); 1579 #endif 1580 if (error && error != ENOMEM) 1581 return (error); 1582 1583 if (retval) { 1584 if (req.oldptr && req.oldidx > req.validlen) 1585 *retval = req.validlen; 1586 else 1587 *retval = req.oldidx; 1588 } 1589 return (error); 1590 } 1591 1592 int 1593 sysctl_int_range(SYSCTL_HANDLER_ARGS, int low, int high) 1594 { 1595 int error, value; 1596 1597 value = *(int *)arg1; 1598 error = sysctl_handle_int(oidp, &value, 0, req); 1599 if (error || !req->newptr) 1600 return (error); 1601 if (value < low || value > high) 1602 return (EINVAL); 1603 *(int *)arg1 = value; 1604 return (0); 1605 } 1606 1607 /* 1608 * Drain into a sysctl struct. The user buffer should be wired if a page 1609 * fault would cause issue. 1610 */ 1611 static int 1612 sbuf_sysctl_drain(void *arg, const char *data, int len) 1613 { 1614 struct sysctl_req *req = arg; 1615 int error; 1616 1617 error = SYSCTL_OUT(req, data, len); 1618 KASSERT(error >= 0, ("Got unexpected negative value %d", error)); 1619 return (error == 0 ? len : -error); 1620 } 1621 1622 struct sbuf * 1623 sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, 1624 struct sysctl_req *req) 1625 { 1626 1627 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN); 1628 sbuf_set_drain(s, sbuf_sysctl_drain, req); 1629 return (s); 1630 } 1631 1632 /* 1633 * The exclusive sysctl lock only protects its topology, and is 1634 * very expensive, but allows us to use a pcpu shared lock for 1635 * critical path accesses. 1636 */ 1637 void 1638 _sysctl_xlock(void) 1639 { 1640 globaldata_t gd; 1641 int i; 1642 1643 for (i = 0; i < ncpus; ++i) { 1644 gd = globaldata_find(i); 1645 lockmgr(&gd->gd_sysctllock, LK_EXCLUSIVE); 1646 } 1647 } 1648 1649 void 1650 _sysctl_xunlock(void) 1651 { 1652 globaldata_t gd; 1653 int i; 1654 1655 for (i = 0; i < ncpus; ++i) { 1656 gd = globaldata_find(i); 1657 lockmgr(&gd->gd_sysctllock, LK_RELEASE); 1658 } 1659 } 1660