geom_subr.c revision 115623
1/*- 2 * Copyright (c) 2002 Poul-Henning Kamp 3 * Copyright (c) 2002 Networks Associates Technology, Inc. 4 * All rights reserved. 5 * 6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp 7 * and NAI Labs, the Security Research Division of Network Associates, Inc. 8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 9 * DARPA CHATS research program. 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. The names of the authors may not be used to endorse or promote 20 * products derived from this software without specific prior written 21 * permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 * $FreeBSD: head/sys/geom/geom_subr.c 115623 2003-06-01 13:30:39Z phk $ 36 */ 37 38 39#include <sys/param.h> 40#include <sys/systm.h> 41#include <sys/devicestat.h> 42#include <sys/kernel.h> 43#include <sys/malloc.h> 44#include <sys/bio.h> 45#include <sys/sysctl.h> 46#include <sys/proc.h> 47#include <sys/kthread.h> 48#include <sys/lock.h> 49#include <sys/mutex.h> 50#include <sys/errno.h> 51#include <sys/sbuf.h> 52#include <geom/geom.h> 53#include <geom/geom_int.h> 54#include <machine/stdarg.h> 55 56struct class_list_head g_classes = LIST_HEAD_INITIALIZER(g_classes); 57static struct g_tailq_head geoms = TAILQ_HEAD_INITIALIZER(geoms); 58char *g_wait_event, *g_wait_up, *g_wait_down, *g_wait_sim; 59 60 61struct g_hh00 { 62 struct g_class *mp; 63 int error; 64}; 65 66/* 67 * This event offers a new class a chance to taste all preexisting providers. 68 */ 69static void 70g_load_class(void *arg, int flag) 71{ 72 struct g_hh00 *hh; 73 struct g_class *mp2, *mp; 74 struct g_geom *gp; 75 struct g_provider *pp; 76 77 g_topology_assert(); 78 if (flag == EV_CANCEL) /* XXX: can't happen ? */ 79 return; 80 if (g_shutdown) 81 return; 82 83 hh = arg; 84 mp = hh->mp; 85 g_free(hh); 86 g_trace(G_T_TOPOLOGY, "g_load_class(%s)", mp->name); 87 88 if (mp->init != NULL) 89 mp->init(mp); 90 LIST_INIT(&mp->geom); 91 LIST_INSERT_HEAD(&g_classes, mp, class); 92 if (mp->taste == NULL) 93 return; 94 LIST_FOREACH(mp2, &g_classes, class) { 95 if (mp == mp2) 96 continue; 97 LIST_FOREACH(gp, &mp2->geom, geom) { 98 LIST_FOREACH(pp, &gp->provider, provider) { 99 mp->taste(mp, pp, 0); 100 g_topology_assert(); 101 } 102 } 103 } 104} 105 106static void 107g_unload_class(void *arg, int flag) 108{ 109 struct g_hh00 *hh; 110 struct g_class *mp; 111 struct g_geom *gp; 112 struct g_provider *pp; 113 struct g_consumer *cp; 114 int error; 115 116 g_topology_assert(); 117 hh = arg; 118 mp = hh->mp; 119 g_trace(G_T_TOPOLOGY, "g_unload_class(%s)", mp->name); 120 if (mp->destroy_geom == NULL) { 121 hh->error = EOPNOTSUPP; 122 return; 123 } 124 125 /* We refuse to unload if anything is open */ 126 LIST_FOREACH(gp, &mp->geom, geom) { 127 LIST_FOREACH(pp, &gp->provider, provider) 128 if (pp->acr || pp->acw || pp->ace) { 129 hh->error = EBUSY; 130 return; 131 } 132 LIST_FOREACH(cp, &gp->consumer, consumer) 133 if (cp->acr || cp->acw || cp->ace) { 134 hh->error = EBUSY; 135 return; 136 } 137 } 138 139 /* Bar new entries */ 140 mp->taste = NULL; 141 mp->config = NULL; 142 143 error = 0; 144 LIST_FOREACH(gp, &mp->geom, geom) { 145 error = mp->destroy_geom(NULL, mp, gp); 146 if (error != 0) 147 break; 148 } 149 if (error == 0) { 150 LIST_REMOVE(mp, class); 151 if (mp->fini != NULL) 152 mp->fini(mp); 153 } 154 hh->error = error; 155 return; 156} 157 158int 159g_modevent(module_t mod, int type, void *data) 160{ 161 struct g_hh00 *hh; 162 int error; 163 static int g_ignition; 164 165 if (!g_ignition) { 166 g_ignition++; 167 g_init(); 168 } 169 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO); 170 hh->mp = data; 171 error = EOPNOTSUPP; 172 switch (type) { 173 case MOD_LOAD: 174 g_trace(G_T_TOPOLOGY, "g_modevent(%s, LOAD)", hh->mp->name); 175 g_post_event(g_load_class, hh, M_WAITOK, NULL); 176 error = 0; 177 break; 178 case MOD_UNLOAD: 179 g_trace(G_T_TOPOLOGY, "g_modevent(%s, UNLOAD)", hh->mp->name); 180 error = g_waitfor_event(g_unload_class, hh, M_WAITOK, NULL); 181 if (error == 0) 182 error = hh->error; 183 g_waitidle(); 184 KASSERT(LIST_EMPTY(&hh->mp->geom), 185 ("Unloaded class (%s) still has geom", hh->mp->name)); 186 g_free(hh); 187 break; 188 } 189 return (error); 190} 191 192struct g_geom * 193g_new_geomf(struct g_class *mp, const char *fmt, ...) 194{ 195 struct g_geom *gp; 196 va_list ap; 197 struct sbuf *sb; 198 199 g_topology_assert(); 200 va_start(ap, fmt); 201 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 202 sbuf_vprintf(sb, fmt, ap); 203 sbuf_finish(sb); 204 gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO); 205 gp->protect = 0x020016601; 206 gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO); 207 gp->class = mp; 208 gp->rank = 1; 209 LIST_INIT(&gp->consumer); 210 LIST_INIT(&gp->provider); 211 LIST_INSERT_HEAD(&mp->geom, gp, geom); 212 TAILQ_INSERT_HEAD(&geoms, gp, geoms); 213 strcpy(gp->name, sbuf_data(sb)); 214 sbuf_delete(sb); 215 return (gp); 216} 217 218void 219g_destroy_geom(struct g_geom *gp) 220{ 221 222 g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name); 223 g_topology_assert(); 224 KASSERT(LIST_EMPTY(&gp->consumer), 225 ("g_destroy_geom(%s) with consumer(s) [%p]", 226 gp->name, LIST_FIRST(&gp->consumer))); 227 KASSERT(LIST_EMPTY(&gp->provider), 228 ("g_destroy_geom(%s) with provider(s) [%p]", 229 gp->name, LIST_FIRST(&gp->consumer))); 230 g_cancel_event(gp); 231 LIST_REMOVE(gp, geom); 232 TAILQ_REMOVE(&geoms, gp, geoms); 233 g_free(gp->name); 234 g_free(gp); 235} 236 237/* 238 * This function is called (repeatedly) until has withered away. 239 */ 240void 241g_wither_geom(struct g_geom *gp, int error) 242{ 243 struct g_provider *pp, *pp2; 244 struct g_consumer *cp, *cp2; 245 static int once_is_enough; 246 247 if (once_is_enough) 248 return; 249 once_is_enough = 1; 250 g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name); 251 g_topology_assert(); 252 if (!(gp->flags & G_GEOM_WITHER)) { 253 gp->flags |= G_GEOM_WITHER; 254 LIST_FOREACH(pp, &gp->provider, provider) 255 g_orphan_provider(pp, error); 256 } 257 for (pp = LIST_FIRST(&gp->provider); pp != NULL; pp = pp2) { 258 pp2 = LIST_NEXT(pp, provider); 259 if (!LIST_EMPTY(&pp->consumers)) 260 continue; 261 g_destroy_provider(pp); 262 } 263 for (cp = LIST_FIRST(&gp->consumer); cp != NULL; cp = cp2) { 264 cp2 = LIST_NEXT(cp, consumer); 265 if (cp->acr || cp->acw || cp->ace) 266 continue; 267 g_detach(cp); 268 g_destroy_consumer(cp); 269 } 270 if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer)) 271 g_destroy_geom(gp); 272 once_is_enough = 0; 273} 274 275struct g_consumer * 276g_new_consumer(struct g_geom *gp) 277{ 278 struct g_consumer *cp; 279 280 g_topology_assert(); 281 KASSERT(gp->orphan != NULL, 282 ("g_new_consumer on geom(%s) (class %s) without orphan", 283 gp->name, gp->class->name)); 284 285 cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO); 286 cp->protect = 0x020016602; 287 cp->geom = gp; 288 cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED, 289 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX); 290 LIST_INSERT_HEAD(&gp->consumer, cp, consumer); 291 return(cp); 292} 293 294void 295g_destroy_consumer(struct g_consumer *cp) 296{ 297 struct g_geom *gp; 298 299 g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp); 300 g_topology_assert(); 301 KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached")); 302 KASSERT (cp->acr == 0, ("g_destroy_consumer with acr")); 303 KASSERT (cp->acw == 0, ("g_destroy_consumer with acw")); 304 KASSERT (cp->ace == 0, ("g_destroy_consumer with ace")); 305 g_cancel_event(cp); 306 gp = cp->geom; 307 LIST_REMOVE(cp, consumer); 308 devstat_remove_entry(cp->stat); 309 g_free(cp); 310 if (gp->flags & G_GEOM_WITHER) 311 g_wither_geom(gp, 0); 312} 313 314static void 315g_new_provider_event(void *arg, int flag) 316{ 317 struct g_class *mp; 318 struct g_provider *pp; 319 struct g_consumer *cp; 320 int i; 321 322 g_topology_assert(); 323 if (flag == EV_CANCEL) 324 return; 325 if (g_shutdown) 326 return; 327 pp = arg; 328 LIST_FOREACH(mp, &g_classes, class) { 329 if (mp->taste == NULL) 330 continue; 331 i = 1; 332 LIST_FOREACH(cp, &pp->consumers, consumers) 333 if (cp->geom->class == mp) 334 i = 0; 335 if (!i) 336 continue; 337 mp->taste(mp, pp, 0); 338 g_topology_assert(); 339 } 340} 341 342 343struct g_provider * 344g_new_providerf(struct g_geom *gp, const char *fmt, ...) 345{ 346 struct g_provider *pp; 347 struct sbuf *sb; 348 va_list ap; 349 350 g_topology_assert(); 351 va_start(ap, fmt); 352 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 353 sbuf_vprintf(sb, fmt, ap); 354 sbuf_finish(sb); 355 pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO); 356 pp->protect = 0x020016603; 357 pp->name = (char *)(pp + 1); 358 strcpy(pp->name, sbuf_data(sb)); 359 sbuf_delete(sb); 360 LIST_INIT(&pp->consumers); 361 pp->error = ENXIO; 362 pp->geom = gp; 363 pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED, 364 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX); 365 LIST_INSERT_HEAD(&gp->provider, pp, provider); 366 g_post_event(g_new_provider_event, pp, M_WAITOK, pp, NULL); 367 return (pp); 368} 369 370void 371g_error_provider(struct g_provider *pp, int error) 372{ 373 374 pp->error = error; 375} 376 377 378void 379g_destroy_provider(struct g_provider *pp) 380{ 381 struct g_geom *gp; 382 383 g_topology_assert(); 384 KASSERT(LIST_EMPTY(&pp->consumers), 385 ("g_destroy_provider but attached")); 386 KASSERT (pp->acr == 0, ("g_destroy_provider with acr")); 387 KASSERT (pp->acw == 0, ("g_destroy_provider with acw")); 388 KASSERT (pp->acw == 0, ("g_destroy_provider with ace")); 389 g_cancel_event(pp); 390 LIST_REMOVE(pp, provider); 391 gp = pp->geom; 392 devstat_remove_entry(pp->stat); 393 g_free(pp); 394 if ((gp->flags & G_GEOM_WITHER)) 395 g_wither_geom(gp, 0); 396} 397 398/* 399 * We keep the "geoms" list sorted by topological order (== increasing 400 * numerical rank) at all times. 401 * When an attach is done, the attaching geoms rank is invalidated 402 * and it is moved to the tail of the list. 403 * All geoms later in the sequence has their ranks reevaluated in 404 * sequence. If we cannot assign rank to a geom because it's 405 * prerequisites do not have rank, we move that element to the tail 406 * of the sequence with invalid rank as well. 407 * At some point we encounter our original geom and if we stil fail 408 * to assign it a rank, there must be a loop and we fail back to 409 * g_attach() which detach again and calls redo_rank again 410 * to fix up the damage. 411 * It would be much simpler code wise to do it recursively, but we 412 * can't risk that on the kernel stack. 413 */ 414 415static int 416redo_rank(struct g_geom *gp) 417{ 418 struct g_consumer *cp; 419 struct g_geom *gp1, *gp2; 420 int n, m; 421 422 g_topology_assert(); 423 424 /* Invalidate this geoms rank and move it to the tail */ 425 gp1 = TAILQ_NEXT(gp, geoms); 426 if (gp1 != NULL) { 427 gp->rank = 0; 428 TAILQ_REMOVE(&geoms, gp, geoms); 429 TAILQ_INSERT_TAIL(&geoms, gp, geoms); 430 } else { 431 gp1 = gp; 432 } 433 434 /* re-rank the rest of the sequence */ 435 for (; gp1 != NULL; gp1 = gp2) { 436 gp1->rank = 0; 437 m = 1; 438 LIST_FOREACH(cp, &gp1->consumer, consumer) { 439 if (cp->provider == NULL) 440 continue; 441 n = cp->provider->geom->rank; 442 if (n == 0) { 443 m = 0; 444 break; 445 } else if (n >= m) 446 m = n + 1; 447 } 448 gp1->rank = m; 449 gp2 = TAILQ_NEXT(gp1, geoms); 450 451 /* got a rank, moving on */ 452 if (m != 0) 453 continue; 454 455 /* no rank to original geom means loop */ 456 if (gp == gp1) 457 return (ELOOP); 458 459 /* no rank, put it at the end move on */ 460 TAILQ_REMOVE(&geoms, gp1, geoms); 461 TAILQ_INSERT_TAIL(&geoms, gp1, geoms); 462 } 463 return (0); 464} 465 466int 467g_attach(struct g_consumer *cp, struct g_provider *pp) 468{ 469 int error; 470 471 g_topology_assert(); 472 KASSERT(cp->provider == NULL, ("attach but attached")); 473 cp->provider = pp; 474 LIST_INSERT_HEAD(&pp->consumers, cp, consumers); 475 error = redo_rank(cp->geom); 476 if (error) { 477 LIST_REMOVE(cp, consumers); 478 cp->provider = NULL; 479 redo_rank(cp->geom); 480 } 481 return (error); 482} 483 484void 485g_detach(struct g_consumer *cp) 486{ 487 struct g_provider *pp; 488 489 g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp); 490 KASSERT(cp != (void*)0xd0d0d0d0, ("ARGH!")); 491 g_topology_assert(); 492 KASSERT(cp->provider != NULL, ("detach but not attached")); 493 KASSERT(cp->acr == 0, ("detach but nonzero acr")); 494 KASSERT(cp->acw == 0, ("detach but nonzero acw")); 495 KASSERT(cp->ace == 0, ("detach but nonzero ace")); 496 KASSERT(cp->nstart == cp->nend, 497 ("detach with active requests")); 498 pp = cp->provider; 499 LIST_REMOVE(cp, consumers); 500 cp->provider = NULL; 501 if (pp->geom->flags & G_GEOM_WITHER) 502 g_wither_geom(pp->geom, 0); 503 redo_rank(cp->geom); 504} 505 506 507/* 508 * g_access_abs() 509 * 510 * Access-check with absolute new values: Just fall through 511 * and use the relative version. 512 */ 513int 514g_access_abs(struct g_consumer *cp, int acr, int acw, int ace) 515{ 516 517 g_topology_assert(); 518 return(g_access_rel(cp, 519 acr - cp->acr, 520 acw - cp->acw, 521 ace - cp->ace)); 522} 523 524/* 525 * g_access_rel() 526 * 527 * Access-check with delta values. The question asked is "can provider 528 * "cp" change the access counters by the relative amounts dc[rwe] ?" 529 */ 530 531int 532g_access_rel(struct g_consumer *cp, int dcr, int dcw, int dce) 533{ 534 struct g_provider *pp; 535 int pr,pw,pe; 536 int error; 537 538 pp = cp->provider; 539 540 g_trace(G_T_ACCESS, "g_access_rel(%p(%s), %d, %d, %d)", 541 cp, pp->name, dcr, dcw, dce); 542 543 g_topology_assert(); 544 KASSERT(cp->provider != NULL, ("access but not attached")); 545 KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr")); 546 KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw")); 547 KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace")); 548 KASSERT(pp->geom->access != NULL, ("NULL geom->access")); 549 550 /* 551 * If our class cares about being spoiled, and we have been, we 552 * are probably just ahead of the event telling us that. Fail 553 * now rather than having to unravel this later. 554 */ 555 if (cp->geom->spoiled != NULL && cp->spoiled) { 556 KASSERT(dcr <= 0, ("spoiled but dcr = %d", dcr)); 557 KASSERT(dcw <= 0, ("spoiled but dce = %d", dcw)); 558 KASSERT(dce <= 0, ("spoiled but dcw = %d", dce)); 559 } 560 561 /* 562 * Figure out what counts the provider would have had, if this 563 * consumer had (r0w0e0) at this time. 564 */ 565 pr = pp->acr - cp->acr; 566 pw = pp->acw - cp->acw; 567 pe = pp->ace - cp->ace; 568 569 g_trace(G_T_ACCESS, 570 "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)", 571 dcr, dcw, dce, 572 cp->acr, cp->acw, cp->ace, 573 pp->acr, pp->acw, pp->ace, 574 pp, pp->name); 575 576 /* If foot-shooting is enabled, any open on rank#1 is OK */ 577 if ((g_debugflags & 16) && pp->geom->rank == 1) 578 ; 579 /* If we try exclusive but already write: fail */ 580 else if (dce > 0 && pw > 0) 581 return (EPERM); 582 /* If we try write but already exclusive: fail */ 583 else if (dcw > 0 && pe > 0) 584 return (EPERM); 585 /* If we try to open more but provider is error'ed: fail */ 586 else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0) 587 return (pp->error); 588 589 /* Ok then... */ 590 591 error = pp->geom->access(pp, dcr, dcw, dce); 592 if (!error) { 593 /* 594 * If we open first write, spoil any partner consumers. 595 * If we close last write, trigger re-taste. 596 */ 597 if (pp->acw == 0 && dcw != 0) 598 g_spoil(pp, cp); 599 else if (pp->acw != 0 && pp->acw == -dcw && 600 !(pp->geom->flags & G_GEOM_WITHER)) 601 g_post_event(g_new_provider_event, pp, M_WAITOK, 602 pp, NULL); 603 604 pp->acr += dcr; 605 pp->acw += dcw; 606 pp->ace += dce; 607 cp->acr += dcr; 608 cp->acw += dcw; 609 cp->ace += dce; 610 } 611 return (error); 612} 613 614int 615g_handleattr_int(struct bio *bp, const char *attribute, int val) 616{ 617 618 return (g_handleattr(bp, attribute, &val, sizeof val)); 619} 620 621int 622g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val) 623{ 624 625 return (g_handleattr(bp, attribute, &val, sizeof val)); 626} 627 628int 629g_handleattr(struct bio *bp, const char *attribute, void *val, int len) 630{ 631 int error; 632 633 if (strcmp(bp->bio_attribute, attribute)) 634 return (0); 635 if (bp->bio_length != len) { 636 printf("bio_length %jd len %d -> EFAULT\n", 637 (intmax_t)bp->bio_length, len); 638 error = EFAULT; 639 } else { 640 error = 0; 641 bcopy(val, bp->bio_data, len); 642 bp->bio_completed = len; 643 } 644 g_io_deliver(bp, error); 645 return (1); 646} 647 648int 649g_std_access(struct g_provider *pp __unused, 650 int dr __unused, int dw __unused, int de __unused) 651{ 652 653 return (0); 654} 655 656void 657g_std_done(struct bio *bp) 658{ 659 struct bio *bp2; 660 661 bp2 = bp->bio_parent; 662 if (bp2->bio_error == 0) 663 bp2->bio_error = bp->bio_error; 664 bp2->bio_completed += bp->bio_completed; 665 g_destroy_bio(bp); 666 bp2->bio_inbed++; 667 if (bp2->bio_children == bp2->bio_inbed) 668 g_io_deliver(bp2, bp2->bio_error); 669} 670 671/* XXX: maybe this is only g_slice_spoiled */ 672 673void 674g_std_spoiled(struct g_consumer *cp) 675{ 676 struct g_geom *gp; 677 struct g_provider *pp; 678 679 g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp); 680 g_topology_assert(); 681 g_detach(cp); 682 gp = cp->geom; 683 LIST_FOREACH(pp, &gp->provider, provider) 684 g_orphan_provider(pp, ENXIO); 685 g_destroy_consumer(cp); 686 if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer)) 687 g_destroy_geom(gp); 688 else 689 gp->flags |= G_GEOM_WITHER; 690} 691 692/* 693 * Spoiling happens when a provider is opened for writing, but consumers 694 * which are configured by in-band data are attached (slicers for instance). 695 * Since the write might potentially change the in-band data, such consumers 696 * need to re-evaluate their existence after the writing session closes. 697 * We do this by (offering to) tear them down when the open for write happens 698 * in return for a re-taste when it closes again. 699 * Together with the fact that such consumers grab an 'e' bit whenever they 700 * are open, regardless of mode, this ends up DTRT. 701 */ 702 703static void 704g_spoil_event(void *arg, int flag) 705{ 706 struct g_provider *pp; 707 struct g_consumer *cp, *cp2; 708 709 g_topology_assert(); 710 if (flag == EV_CANCEL) 711 return; 712 pp = arg; 713 for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) { 714 cp2 = LIST_NEXT(cp, consumers); 715 if (!cp->spoiled) 716 continue; 717 cp->spoiled = 0; 718 if (cp->geom->spoiled == NULL) 719 continue; 720 cp->geom->spoiled(cp); 721 g_topology_assert(); 722 } 723} 724 725void 726g_spoil(struct g_provider *pp, struct g_consumer *cp) 727{ 728 struct g_consumer *cp2; 729 730 g_topology_assert(); 731 732 LIST_FOREACH(cp2, &pp->consumers, consumers) { 733 if (cp2 == cp) 734 continue; 735/* 736 KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr)); 737 KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw)); 738*/ 739 KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace)); 740 cp2->spoiled++; 741 } 742 g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL); 743} 744 745int 746g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len) 747{ 748 int error, i; 749 750 i = len; 751 error = g_io_getattr(attr, cp, &i, var); 752 if (error) 753 return (error); 754 if (i != len) 755 return (EINVAL); 756 return (0); 757} 758 759/* 760 * Check if the given pointer is a live object 761 */ 762 763void 764g_sanity(void const *ptr) 765{ 766 struct g_class *mp; 767 struct g_geom *gp; 768 struct g_consumer *cp; 769 struct g_provider *pp; 770 771 if (!(g_debugflags & 0x8)) 772 return; 773 LIST_FOREACH(mp, &g_classes, class) { 774 KASSERT(mp != ptr, ("Ptr is live class")); 775 KASSERT(mp->protect == 0x20016600, 776 ("corrupt class %p %x", mp, mp->protect)); 777 LIST_FOREACH(gp, &mp->geom, geom) { 778 KASSERT(gp != ptr, ("Ptr is live geom")); 779 KASSERT(gp->protect == 0x20016601, 780 ("corrupt geom, %p %x", gp, gp->protect)); 781 KASSERT(gp->name != ptr, ("Ptr is live geom's name")); 782 LIST_FOREACH(cp, &gp->consumer, consumer) { 783 KASSERT(cp != ptr, ("Ptr is live consumer")); 784 KASSERT(cp->protect == 0x20016602, 785 ("corrupt consumer %p %x", 786 cp, cp->protect)); 787 } 788 LIST_FOREACH(pp, &gp->provider, provider) { 789 KASSERT(pp != ptr, ("Ptr is live provider")); 790 KASSERT(pp->protect == 0x20016603, 791 ("corrupt provider %p %x", 792 pp, pp->protect)); 793 } 794 } 795 } 796} 797 798