geom_subr.c revision 126798
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 36#include <sys/cdefs.h> 37__FBSDID("$FreeBSD: head/sys/geom/geom_subr.c 126798 2004-03-10 08:49:08Z phk $"); 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 60struct g_hh00 { 61 struct g_class *mp; 62 int error; 63}; 64 65/* 66 * This event offers a new class a chance to taste all preexisting providers. 67 */ 68static void 69g_load_class(void *arg, int flag) 70{ 71 struct g_hh00 *hh; 72 struct g_class *mp2, *mp; 73 struct g_geom *gp; 74 struct g_provider *pp; 75 76 g_topology_assert(); 77 if (flag == EV_CANCEL) /* XXX: can't happen ? */ 78 return; 79 if (g_shutdown) 80 return; 81 82 hh = arg; 83 mp = hh->mp; 84 g_free(hh); 85 g_trace(G_T_TOPOLOGY, "g_load_class(%s)", mp->name); 86 KASSERT(mp->name != NULL && *mp->name != '\0', 87 ("GEOM class has no name")); 88 LIST_FOREACH(mp2, &g_classes, class) { 89 KASSERT(mp2 != mp, 90 ("The GEOM class %s already loaded", mp2->name)); 91 KASSERT(strcmp(mp2->name, mp->name) != 0, 92 ("A GEOM class named %s is already loaded", mp2->name)); 93 } 94 95 LIST_INIT(&mp->geom); 96 LIST_INSERT_HEAD(&g_classes, mp, class); 97 if (mp->init != NULL) 98 mp->init(mp); 99 if (mp->taste == NULL) 100 return; 101 LIST_FOREACH(mp2, &g_classes, class) { 102 if (mp == mp2) 103 continue; 104 LIST_FOREACH(gp, &mp2->geom, geom) { 105 LIST_FOREACH(pp, &gp->provider, provider) { 106 mp->taste(mp, pp, 0); 107 g_topology_assert(); 108 } 109 } 110 } 111} 112 113static void 114g_unload_class(void *arg, int flag) 115{ 116 struct g_hh00 *hh; 117 struct g_class *mp; 118 struct g_geom *gp; 119 struct g_provider *pp; 120 struct g_consumer *cp; 121 int error; 122 123 g_topology_assert(); 124 hh = arg; 125 mp = hh->mp; 126 G_VALID_CLASS(mp); 127 g_trace(G_T_TOPOLOGY, "g_unload_class(%s)", mp->name); 128 129 /* 130 * We allow unloading if we have no geoms, or a class 131 * method we can use to get rid of them. 132 */ 133 if (!LIST_EMPTY(&mp->geom) && mp->destroy_geom == NULL) { 134 hh->error = EOPNOTSUPP; 135 return; 136 } 137 138 /* We refuse to unload if anything is open */ 139 LIST_FOREACH(gp, &mp->geom, geom) { 140 LIST_FOREACH(pp, &gp->provider, provider) 141 if (pp->acr || pp->acw || pp->ace) { 142 hh->error = EBUSY; 143 return; 144 } 145 LIST_FOREACH(cp, &gp->consumer, consumer) 146 if (cp->acr || cp->acw || cp->ace) { 147 hh->error = EBUSY; 148 return; 149 } 150 } 151 152 /* Bar new entries */ 153 mp->taste = NULL; 154 mp->config = NULL; 155 156 error = 0; 157 LIST_FOREACH(gp, &mp->geom, geom) { 158 error = mp->destroy_geom(NULL, mp, gp); 159 if (error != 0) 160 break; 161 } 162 if (error == 0) { 163 if (mp->fini != NULL) 164 mp->fini(mp); 165 LIST_REMOVE(mp, class); 166 } 167 hh->error = error; 168 return; 169} 170 171int 172g_modevent(module_t mod, int type, void *data) 173{ 174 struct g_hh00 *hh; 175 int error; 176 static int g_ignition; 177 178 if (!g_ignition) { 179 g_ignition++; 180 g_init(); 181 } 182 hh = g_malloc(sizeof *hh, M_WAITOK | M_ZERO); 183 hh->mp = data; 184 error = EOPNOTSUPP; 185 switch (type) { 186 case MOD_LOAD: 187 g_trace(G_T_TOPOLOGY, "g_modevent(%s, LOAD)", hh->mp->name); 188 g_post_event(g_load_class, hh, M_WAITOK, NULL); 189 error = 0; 190 break; 191 case MOD_UNLOAD: 192 g_trace(G_T_TOPOLOGY, "g_modevent(%s, UNLOAD)", hh->mp->name); 193 error = g_waitfor_event(g_unload_class, hh, M_WAITOK, NULL); 194 if (error == 0) 195 error = hh->error; 196 if (error == 0) { 197 g_waitidle(); 198 KASSERT(LIST_EMPTY(&hh->mp->geom), 199 ("Unloaded class (%s) still has geom", hh->mp->name)); 200 } 201 g_free(hh); 202 break; 203 default: 204 g_free(hh); 205 break; 206 } 207 return (error); 208} 209 210struct g_geom * 211g_new_geomf(struct g_class *mp, const char *fmt, ...) 212{ 213 struct g_geom *gp; 214 va_list ap; 215 struct sbuf *sb; 216 217 g_topology_assert(); 218 G_VALID_CLASS(mp); 219 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 220 va_start(ap, fmt); 221 sbuf_vprintf(sb, fmt, ap); 222 va_end(ap); 223 sbuf_finish(sb); 224 gp = g_malloc(sizeof *gp, M_WAITOK | M_ZERO); 225 gp->name = g_malloc(sbuf_len(sb) + 1, M_WAITOK | M_ZERO); 226 gp->class = mp; 227 gp->rank = 1; 228 LIST_INIT(&gp->consumer); 229 LIST_INIT(&gp->provider); 230 LIST_INSERT_HEAD(&mp->geom, gp, geom); 231 TAILQ_INSERT_HEAD(&geoms, gp, geoms); 232 strcpy(gp->name, sbuf_data(sb)); 233 sbuf_delete(sb); 234 return (gp); 235} 236 237void 238g_destroy_geom(struct g_geom *gp) 239{ 240 241 g_topology_assert(); 242 G_VALID_GEOM(gp); 243 g_trace(G_T_TOPOLOGY, "g_destroy_geom(%p(%s))", gp, gp->name); 244 KASSERT(LIST_EMPTY(&gp->consumer), 245 ("g_destroy_geom(%s) with consumer(s) [%p]", 246 gp->name, LIST_FIRST(&gp->consumer))); 247 KASSERT(LIST_EMPTY(&gp->provider), 248 ("g_destroy_geom(%s) with provider(s) [%p]", 249 gp->name, LIST_FIRST(&gp->provider))); 250 g_cancel_event(gp); 251 LIST_REMOVE(gp, geom); 252 TAILQ_REMOVE(&geoms, gp, geoms); 253 g_free(gp->name); 254 g_free(gp); 255} 256 257/* 258 * This function is called (repeatedly) until the has withered away. 259 */ 260void 261g_wither_geom(struct g_geom *gp, int error) 262{ 263 struct g_provider *pp, *pp2; 264 struct g_consumer *cp, *cp2; 265 static int once_is_enough; 266 267 g_topology_assert(); 268 G_VALID_GEOM(gp); 269 if (once_is_enough) 270 return; 271 once_is_enough = 1; 272 g_trace(G_T_TOPOLOGY, "g_wither_geom(%p(%s))", gp, gp->name); 273 if (!(gp->flags & G_GEOM_WITHER)) { 274 gp->flags |= G_GEOM_WITHER; 275 LIST_FOREACH(pp, &gp->provider, provider) 276 if (!(pp->flags & G_PF_ORPHAN)) 277 g_orphan_provider(pp, error); 278 } 279 for (pp = LIST_FIRST(&gp->provider); pp != NULL; pp = pp2) { 280 pp2 = LIST_NEXT(pp, provider); 281 if (!LIST_EMPTY(&pp->consumers)) 282 continue; 283 g_destroy_provider(pp); 284 } 285 for (cp = LIST_FIRST(&gp->consumer); cp != NULL; cp = cp2) { 286 cp2 = LIST_NEXT(cp, consumer); 287 if (cp->acr || cp->acw || cp->ace) 288 continue; 289 g_detach(cp); 290 g_destroy_consumer(cp); 291 } 292 if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer)) 293 g_destroy_geom(gp); 294 once_is_enough = 0; 295} 296 297struct g_consumer * 298g_new_consumer(struct g_geom *gp) 299{ 300 struct g_consumer *cp; 301 302 g_topology_assert(); 303 G_VALID_GEOM(gp); 304 KASSERT(!(gp->flags & G_GEOM_WITHER), 305 ("g_new_consumer on WITHERing geom(%s) (class %s)", 306 gp->name, gp->class->name)); 307 KASSERT(gp->orphan != NULL, 308 ("g_new_consumer on geom(%s) (class %s) without orphan", 309 gp->name, gp->class->name)); 310 311 cp = g_malloc(sizeof *cp, M_WAITOK | M_ZERO); 312 cp->geom = gp; 313 cp->stat = devstat_new_entry(cp, -1, 0, DEVSTAT_ALL_SUPPORTED, 314 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX); 315 LIST_INSERT_HEAD(&gp->consumer, cp, consumer); 316 return(cp); 317} 318 319void 320g_destroy_consumer(struct g_consumer *cp) 321{ 322 struct g_geom *gp; 323 324 g_topology_assert(); 325 G_VALID_CONSUMER(cp); 326 g_trace(G_T_TOPOLOGY, "g_destroy_consumer(%p)", cp); 327 KASSERT (cp->provider == NULL, ("g_destroy_consumer but attached")); 328 KASSERT (cp->acr == 0, ("g_destroy_consumer with acr")); 329 KASSERT (cp->acw == 0, ("g_destroy_consumer with acw")); 330 KASSERT (cp->ace == 0, ("g_destroy_consumer with ace")); 331 g_cancel_event(cp); 332 gp = cp->geom; 333 LIST_REMOVE(cp, consumer); 334 devstat_remove_entry(cp->stat); 335 g_free(cp); 336 if (gp->flags & G_GEOM_WITHER) 337 g_wither_geom(gp, 0); 338} 339 340static void 341g_new_provider_event(void *arg, int flag) 342{ 343 struct g_class *mp; 344 struct g_provider *pp; 345 struct g_consumer *cp; 346 int i; 347 348 g_topology_assert(); 349 if (flag == EV_CANCEL) 350 return; 351 if (g_shutdown) 352 return; 353 pp = arg; 354 G_VALID_PROVIDER(pp); 355 LIST_FOREACH(mp, &g_classes, class) { 356 if (mp->taste == NULL) 357 continue; 358 i = 1; 359 LIST_FOREACH(cp, &pp->consumers, consumers) 360 if (cp->geom->class == mp) 361 i = 0; 362 if (!i) 363 continue; 364 mp->taste(mp, pp, 0); 365 g_topology_assert(); 366 } 367} 368 369 370struct g_provider * 371g_new_providerf(struct g_geom *gp, const char *fmt, ...) 372{ 373 struct g_provider *pp; 374 struct sbuf *sb; 375 va_list ap; 376 377 g_topology_assert(); 378 G_VALID_GEOM(gp); 379 KASSERT(gp->start != NULL, 380 ("new provider on geom(%s) without ->start (class %s)", 381 gp->name, gp->class->name)); 382 KASSERT(!(gp->flags & G_GEOM_WITHER), 383 ("new provider on WITHERing geom(%s) (class %s)", 384 gp->name, gp->class->name)); 385 sb = sbuf_new(NULL, NULL, 0, SBUF_AUTOEXTEND); 386 va_start(ap, fmt); 387 sbuf_vprintf(sb, fmt, ap); 388 va_end(ap); 389 sbuf_finish(sb); 390 pp = g_malloc(sizeof *pp + sbuf_len(sb) + 1, M_WAITOK | M_ZERO); 391 pp->name = (char *)(pp + 1); 392 strcpy(pp->name, sbuf_data(sb)); 393 sbuf_delete(sb); 394 LIST_INIT(&pp->consumers); 395 pp->error = ENXIO; 396 pp->geom = gp; 397 pp->stat = devstat_new_entry(pp, -1, 0, DEVSTAT_ALL_SUPPORTED, 398 DEVSTAT_TYPE_DIRECT, DEVSTAT_PRIORITY_MAX); 399 LIST_INSERT_HEAD(&gp->provider, pp, provider); 400 g_post_event(g_new_provider_event, pp, M_WAITOK, pp, NULL); 401 return (pp); 402} 403 404void 405g_error_provider(struct g_provider *pp, int error) 406{ 407 408 /* G_VALID_PROVIDER(pp); We may not have g_topology */ 409 pp->error = error; 410} 411 412struct g_provider * 413g_provider_by_name(char const *arg) 414{ 415 struct g_class *cp; 416 struct g_geom *gp; 417 struct g_provider *pp; 418 419 LIST_FOREACH(cp, &g_classes, class) { 420 LIST_FOREACH(gp, &cp->geom, geom) { 421 LIST_FOREACH(pp, &gp->provider, provider) { 422 if (!strcmp(arg, pp->name)) 423 return (pp); 424 } 425 } 426 } 427 return (NULL); 428} 429 430void 431g_destroy_provider(struct g_provider *pp) 432{ 433 struct g_geom *gp; 434 435 g_topology_assert(); 436 G_VALID_PROVIDER(pp); 437 KASSERT(LIST_EMPTY(&pp->consumers), 438 ("g_destroy_provider but attached")); 439 KASSERT (pp->acr == 0, ("g_destroy_provider with acr")); 440 KASSERT (pp->acw == 0, ("g_destroy_provider with acw")); 441 KASSERT (pp->acw == 0, ("g_destroy_provider with ace")); 442 g_cancel_event(pp); 443 LIST_REMOVE(pp, provider); 444 gp = pp->geom; 445 devstat_remove_entry(pp->stat); 446 g_free(pp); 447 if ((gp->flags & G_GEOM_WITHER)) 448 g_wither_geom(gp, 0); 449} 450 451/* 452 * We keep the "geoms" list sorted by topological order (== increasing 453 * numerical rank) at all times. 454 * When an attach is done, the attaching geoms rank is invalidated 455 * and it is moved to the tail of the list. 456 * All geoms later in the sequence has their ranks reevaluated in 457 * sequence. If we cannot assign rank to a geom because it's 458 * prerequisites do not have rank, we move that element to the tail 459 * of the sequence with invalid rank as well. 460 * At some point we encounter our original geom and if we stil fail 461 * to assign it a rank, there must be a loop and we fail back to 462 * g_attach() which detach again and calls redo_rank again 463 * to fix up the damage. 464 * It would be much simpler code wise to do it recursively, but we 465 * can't risk that on the kernel stack. 466 */ 467 468static int 469redo_rank(struct g_geom *gp) 470{ 471 struct g_consumer *cp; 472 struct g_geom *gp1, *gp2; 473 int n, m; 474 475 g_topology_assert(); 476 G_VALID_GEOM(gp); 477 478 /* Invalidate this geoms rank and move it to the tail */ 479 gp1 = TAILQ_NEXT(gp, geoms); 480 if (gp1 != NULL) { 481 gp->rank = 0; 482 TAILQ_REMOVE(&geoms, gp, geoms); 483 TAILQ_INSERT_TAIL(&geoms, gp, geoms); 484 } else { 485 gp1 = gp; 486 } 487 488 /* re-rank the rest of the sequence */ 489 for (; gp1 != NULL; gp1 = gp2) { 490 gp1->rank = 0; 491 m = 1; 492 LIST_FOREACH(cp, &gp1->consumer, consumer) { 493 if (cp->provider == NULL) 494 continue; 495 n = cp->provider->geom->rank; 496 if (n == 0) { 497 m = 0; 498 break; 499 } else if (n >= m) 500 m = n + 1; 501 } 502 gp1->rank = m; 503 gp2 = TAILQ_NEXT(gp1, geoms); 504 505 /* got a rank, moving on */ 506 if (m != 0) 507 continue; 508 509 /* no rank to original geom means loop */ 510 if (gp == gp1) 511 return (ELOOP); 512 513 /* no rank, put it at the end move on */ 514 TAILQ_REMOVE(&geoms, gp1, geoms); 515 TAILQ_INSERT_TAIL(&geoms, gp1, geoms); 516 } 517 return (0); 518} 519 520int 521g_attach(struct g_consumer *cp, struct g_provider *pp) 522{ 523 int error; 524 525 g_topology_assert(); 526 G_VALID_CONSUMER(cp); 527 G_VALID_PROVIDER(pp); 528 KASSERT(cp->provider == NULL, ("attach but attached")); 529 cp->provider = pp; 530 LIST_INSERT_HEAD(&pp->consumers, cp, consumers); 531 error = redo_rank(cp->geom); 532 if (error) { 533 LIST_REMOVE(cp, consumers); 534 cp->provider = NULL; 535 redo_rank(cp->geom); 536 } 537 return (error); 538} 539 540void 541g_detach(struct g_consumer *cp) 542{ 543 struct g_provider *pp; 544 545 g_topology_assert(); 546 G_VALID_CONSUMER(cp); 547 g_trace(G_T_TOPOLOGY, "g_detach(%p)", cp); 548 KASSERT(cp->provider != NULL, ("detach but not attached")); 549 KASSERT(cp->acr == 0, ("detach but nonzero acr")); 550 KASSERT(cp->acw == 0, ("detach but nonzero acw")); 551 KASSERT(cp->ace == 0, ("detach but nonzero ace")); 552 KASSERT(cp->nstart == cp->nend, 553 ("detach with active requests")); 554 pp = cp->provider; 555 LIST_REMOVE(cp, consumers); 556 cp->provider = NULL; 557 if (pp->geom->flags & G_GEOM_WITHER) 558 g_wither_geom(pp->geom, 0); 559 else if (pp->flags & G_PF_WITHER) 560 g_destroy_provider(pp); 561 redo_rank(cp->geom); 562} 563 564/* 565 * g_access() 566 * 567 * Access-check with delta values. The question asked is "can provider 568 * "cp" change the access counters by the relative amounts dc[rwe] ?" 569 */ 570 571int 572g_access(struct g_consumer *cp, int dcr, int dcw, int dce) 573{ 574 struct g_provider *pp; 575 int pr,pw,pe; 576 int error; 577 578 g_topology_assert(); 579 G_VALID_CONSUMER(cp); 580 pp = cp->provider; 581 G_VALID_PROVIDER(pp); 582 583 g_trace(G_T_ACCESS, "g_access(%p(%s), %d, %d, %d)", 584 cp, pp->name, dcr, dcw, dce); 585 586 KASSERT(cp->provider != NULL, ("access but not attached")); 587 KASSERT(cp->acr + dcr >= 0, ("access resulting in negative acr")); 588 KASSERT(cp->acw + dcw >= 0, ("access resulting in negative acw")); 589 KASSERT(cp->ace + dce >= 0, ("access resulting in negative ace")); 590 KASSERT(dcr != 0 || dcw != 0 || dce != 0, ("NOP access request")); 591 KASSERT(pp->geom->access != NULL, ("NULL geom->access")); 592 593 /* 594 * If our class cares about being spoiled, and we have been, we 595 * are probably just ahead of the event telling us that. Fail 596 * now rather than having to unravel this later. 597 */ 598 if (cp->geom->spoiled != NULL && cp->spoiled) { 599 KASSERT(dcr <= 0, ("spoiled but dcr = %d", dcr)); 600 KASSERT(dcw <= 0, ("spoiled but dcw = %d", dcw)); 601 KASSERT(dce <= 0, ("spoiled but dce = %d", dce)); 602 } 603 604 /* 605 * Figure out what counts the provider would have had, if this 606 * consumer had (r0w0e0) at this time. 607 */ 608 pr = pp->acr - cp->acr; 609 pw = pp->acw - cp->acw; 610 pe = pp->ace - cp->ace; 611 612 g_trace(G_T_ACCESS, 613 "open delta:[r%dw%de%d] old:[r%dw%de%d] provider:[r%dw%de%d] %p(%s)", 614 dcr, dcw, dce, 615 cp->acr, cp->acw, cp->ace, 616 pp->acr, pp->acw, pp->ace, 617 pp, pp->name); 618 619 /* If foot-shooting is enabled, any open on rank#1 is OK */ 620 if ((g_debugflags & 16) && pp->geom->rank == 1) 621 ; 622 /* If we try exclusive but already write: fail */ 623 else if (dce > 0 && pw > 0) 624 return (EPERM); 625 /* If we try write but already exclusive: fail */ 626 else if (dcw > 0 && pe > 0) 627 return (EPERM); 628 /* If we try to open more but provider is error'ed: fail */ 629 else if ((dcr > 0 || dcw > 0 || dce > 0) && pp->error != 0) 630 return (pp->error); 631 632 /* Ok then... */ 633 634 error = pp->geom->access(pp, dcr, dcw, dce); 635 KASSERT(dcr > 0 || dcw > 0 || dce > 0 || error == 0, 636 ("Geom provider %s::%s failed closing ->access()", 637 pp->geom->class->name, pp->name)); 638 if (!error) { 639 /* 640 * If we open first write, spoil any partner consumers. 641 * If we close last write, trigger re-taste. 642 */ 643 if (pp->acw == 0 && dcw != 0) 644 g_spoil(pp, cp); 645 else if (pp->acw != 0 && pp->acw == -dcw && 646 !(pp->geom->flags & G_GEOM_WITHER)) 647 g_post_event(g_new_provider_event, pp, M_WAITOK, 648 pp, NULL); 649 650 pp->acr += dcr; 651 pp->acw += dcw; 652 pp->ace += dce; 653 cp->acr += dcr; 654 cp->acw += dcw; 655 cp->ace += dce; 656 } 657 return (error); 658} 659 660int 661g_handleattr_int(struct bio *bp, const char *attribute, int val) 662{ 663 664 return (g_handleattr(bp, attribute, &val, sizeof val)); 665} 666 667int 668g_handleattr_off_t(struct bio *bp, const char *attribute, off_t val) 669{ 670 671 return (g_handleattr(bp, attribute, &val, sizeof val)); 672} 673 674int 675g_handleattr(struct bio *bp, const char *attribute, void *val, int len) 676{ 677 int error; 678 679 if (strcmp(bp->bio_attribute, attribute)) 680 return (0); 681 if (bp->bio_length != len) { 682 printf("bio_length %jd len %d -> EFAULT\n", 683 (intmax_t)bp->bio_length, len); 684 error = EFAULT; 685 } else { 686 error = 0; 687 bcopy(val, bp->bio_data, len); 688 bp->bio_completed = len; 689 } 690 g_io_deliver(bp, error); 691 return (1); 692} 693 694int 695g_std_access(struct g_provider *pp, 696 int dr __unused, int dw __unused, int de __unused) 697{ 698 699 g_topology_assert(); 700 G_VALID_PROVIDER(pp); 701 return (0); 702} 703 704void 705g_std_done(struct bio *bp) 706{ 707 struct bio *bp2; 708 709 bp2 = bp->bio_parent; 710 if (bp2->bio_error == 0) 711 bp2->bio_error = bp->bio_error; 712 bp2->bio_completed += bp->bio_completed; 713 g_destroy_bio(bp); 714 bp2->bio_inbed++; 715 if (bp2->bio_children == bp2->bio_inbed) 716 g_io_deliver(bp2, bp2->bio_error); 717} 718 719/* XXX: maybe this is only g_slice_spoiled */ 720 721void 722g_std_spoiled(struct g_consumer *cp) 723{ 724 struct g_geom *gp; 725 struct g_provider *pp; 726 727 g_topology_assert(); 728 G_VALID_CONSUMER(cp); 729 g_trace(G_T_TOPOLOGY, "g_std_spoiled(%p)", cp); 730 g_detach(cp); 731 gp = cp->geom; 732 LIST_FOREACH(pp, &gp->provider, provider) 733 g_orphan_provider(pp, ENXIO); 734 g_destroy_consumer(cp); 735 if (LIST_EMPTY(&gp->provider) && LIST_EMPTY(&gp->consumer)) 736 g_destroy_geom(gp); 737 else 738 gp->flags |= G_GEOM_WITHER; 739} 740 741/* 742 * Spoiling happens when a provider is opened for writing, but consumers 743 * which are configured by in-band data are attached (slicers for instance). 744 * Since the write might potentially change the in-band data, such consumers 745 * need to re-evaluate their existence after the writing session closes. 746 * We do this by (offering to) tear them down when the open for write happens 747 * in return for a re-taste when it closes again. 748 * Together with the fact that such consumers grab an 'e' bit whenever they 749 * are open, regardless of mode, this ends up DTRT. 750 */ 751 752static void 753g_spoil_event(void *arg, int flag) 754{ 755 struct g_provider *pp; 756 struct g_consumer *cp, *cp2; 757 758 g_topology_assert(); 759 if (flag == EV_CANCEL) 760 return; 761 pp = arg; 762 G_VALID_PROVIDER(pp); 763 for (cp = LIST_FIRST(&pp->consumers); cp != NULL; cp = cp2) { 764 cp2 = LIST_NEXT(cp, consumers); 765 if (!cp->spoiled) 766 continue; 767 cp->spoiled = 0; 768 if (cp->geom->spoiled == NULL) 769 continue; 770 cp->geom->spoiled(cp); 771 g_topology_assert(); 772 } 773} 774 775void 776g_spoil(struct g_provider *pp, struct g_consumer *cp) 777{ 778 struct g_consumer *cp2; 779 780 g_topology_assert(); 781 G_VALID_PROVIDER(pp); 782 G_VALID_CONSUMER(cp); 783 784 LIST_FOREACH(cp2, &pp->consumers, consumers) { 785 if (cp2 == cp) 786 continue; 787/* 788 KASSERT(cp2->acr == 0, ("spoiling cp->acr = %d", cp2->acr)); 789 KASSERT(cp2->acw == 0, ("spoiling cp->acw = %d", cp2->acw)); 790*/ 791 KASSERT(cp2->ace == 0, ("spoiling cp->ace = %d", cp2->ace)); 792 cp2->spoiled++; 793 } 794 g_post_event(g_spoil_event, pp, M_WAITOK, pp, NULL); 795} 796 797int 798g_getattr__(const char *attr, struct g_consumer *cp, void *var, int len) 799{ 800 int error, i; 801 802 i = len; 803 error = g_io_getattr(attr, cp, &i, var); 804 if (error) 805 return (error); 806 if (i != len) 807 return (EINVAL); 808 return (0); 809} 810 811#ifdef DIAGNOSTIC 812/* 813 * This function walks (topologically unsafely) the mesh and return a 814 * non-zero integer if it finds the argument pointer is an object. 815 * The return value indicates which type of object it is belived to be. 816 * If topology is not locked, this function is potentially dangerous, 817 * but since it is for debugging purposes and can be useful for instance 818 * from DDB, we do not assert topology lock is held. 819 */ 820int 821g_valid_obj(void const *ptr) 822{ 823 struct g_class *mp; 824 struct g_geom *gp; 825 struct g_consumer *cp; 826 struct g_provider *pp; 827 828 LIST_FOREACH(mp, &g_classes, class) { 829 if (ptr == mp) 830 return (1); 831 LIST_FOREACH(gp, &mp->geom, geom) { 832 if (ptr == gp) 833 return (2); 834 LIST_FOREACH(cp, &gp->consumer, consumer) 835 if (ptr == cp) 836 return (3); 837 LIST_FOREACH(pp, &gp->provider, provider) 838 if (ptr == pp) 839 return (4); 840 } 841 } 842 return(0); 843} 844#endif 845