g_mountver.c revision 223921
1/*- 2 * Copyright (c) 2010 Edward Tomasz Napierala <trasz@FreeBSD.org> 3 * Copyright (c) 2004-2006 Pawel Jakub Dawidek <pjd@FreeBSD.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28#include <sys/cdefs.h> 29__FBSDID("$FreeBSD: head/sys/geom/mountver/g_mountver.c 223921 2011-07-11 05:22:31Z ae $"); 30 31#include <sys/param.h> 32#include <sys/systm.h> 33#include <sys/kernel.h> 34#include <sys/module.h> 35#include <sys/lock.h> 36#include <sys/mutex.h> 37#include <sys/bio.h> 38#include <sys/disk.h> 39#include <sys/sbuf.h> 40#include <sys/sysctl.h> 41#include <sys/malloc.h> 42#include <sys/eventhandler.h> 43#include <geom/geom.h> 44#include <geom/mountver/g_mountver.h> 45 46 47SYSCTL_DECL(_kern_geom); 48SYSCTL_NODE(_kern_geom, OID_AUTO, mountver, CTLFLAG_RW, 49 0, "GEOM_MOUNTVER stuff"); 50static u_int g_mountver_debug = 0; 51static u_int g_mountver_check_ident = 1; 52SYSCTL_UINT(_kern_geom_mountver, OID_AUTO, debug, CTLFLAG_RW, 53 &g_mountver_debug, 0, "Debug level"); 54SYSCTL_UINT(_kern_geom_mountver, OID_AUTO, check_ident, CTLFLAG_RW, 55 &g_mountver_check_ident, 0, "Check disk ident when reattaching"); 56 57static eventhandler_tag g_mountver_pre_sync = NULL; 58 59static void g_mountver_queue(struct bio *bp); 60static void g_mountver_orphan(struct g_consumer *cp); 61static int g_mountver_destroy(struct g_geom *gp, boolean_t force); 62static g_taste_t g_mountver_taste; 63static int g_mountver_destroy_geom(struct gctl_req *req, struct g_class *mp, 64 struct g_geom *gp); 65static void g_mountver_config(struct gctl_req *req, struct g_class *mp, 66 const char *verb); 67static void g_mountver_dumpconf(struct sbuf *sb, const char *indent, 68 struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp); 69static void g_mountver_init(struct g_class *mp); 70static void g_mountver_fini(struct g_class *mp); 71 72struct g_class g_mountver_class = { 73 .name = G_MOUNTVER_CLASS_NAME, 74 .version = G_VERSION, 75 .ctlreq = g_mountver_config, 76 .taste = g_mountver_taste, 77 .destroy_geom = g_mountver_destroy_geom, 78 .init = g_mountver_init, 79 .fini = g_mountver_fini 80}; 81 82static void 83g_mountver_done(struct bio *bp) 84{ 85 struct g_geom *gp; 86 struct bio *pbp; 87 88 if (bp->bio_error != ENXIO) { 89 g_std_done(bp); 90 return; 91 } 92 93 /* 94 * When the device goes away, it's possible that few requests 95 * will be completed with ENXIO before g_mountver_orphan() 96 * gets called. To work around that, we have to queue requests 97 * that failed with ENXIO, in order to send them later. 98 */ 99 gp = bp->bio_from->geom; 100 101 pbp = bp->bio_parent; 102 KASSERT(pbp->bio_to == LIST_FIRST(&gp->provider), 103 ("parent request was for someone else")); 104 g_destroy_bio(bp); 105 pbp->bio_inbed++; 106 g_mountver_queue(pbp); 107} 108 109static void 110g_mountver_send(struct bio *bp) 111{ 112 struct g_geom *gp; 113 struct bio *cbp; 114 115 gp = bp->bio_to->geom; 116 117 cbp = g_clone_bio(bp); 118 if (cbp == NULL) { 119 g_io_deliver(bp, ENOMEM); 120 return; 121 } 122 123 cbp->bio_done = g_mountver_done; 124 g_io_request(cbp, LIST_FIRST(&gp->consumer)); 125} 126 127static void 128g_mountver_queue(struct bio *bp) 129{ 130 struct g_mountver_softc *sc; 131 struct g_geom *gp; 132 133 gp = bp->bio_to->geom; 134 sc = gp->softc; 135 136 mtx_lock(&sc->sc_mtx); 137 TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue); 138 mtx_unlock(&sc->sc_mtx); 139} 140 141static void 142g_mountver_send_queued(struct g_geom *gp) 143{ 144 struct g_mountver_softc *sc; 145 struct bio *bp; 146 147 sc = gp->softc; 148 149 mtx_lock(&sc->sc_mtx); 150 while ((bp = TAILQ_FIRST(&sc->sc_queue)) != NULL) { 151 TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue); 152 G_MOUNTVER_LOGREQ(bp, "Sending queued request."); 153 g_mountver_send(bp); 154 } 155 mtx_unlock(&sc->sc_mtx); 156} 157 158static void 159g_mountver_discard_queued(struct g_geom *gp) 160{ 161 struct g_mountver_softc *sc; 162 struct bio *bp; 163 164 sc = gp->softc; 165 166 mtx_lock(&sc->sc_mtx); 167 while ((bp = TAILQ_FIRST(&sc->sc_queue)) != NULL) { 168 TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue); 169 G_MOUNTVER_LOGREQ(bp, "Discarding queued request."); 170 g_io_deliver(bp, ENXIO); 171 } 172 mtx_unlock(&sc->sc_mtx); 173} 174 175static void 176g_mountver_start(struct bio *bp) 177{ 178 struct g_mountver_softc *sc; 179 struct g_geom *gp; 180 181 gp = bp->bio_to->geom; 182 sc = gp->softc; 183 G_MOUNTVER_LOGREQ(bp, "Request received."); 184 185 /* 186 * It is possible that some bios were returned with ENXIO, even though 187 * orphaning didn't happen yet. In that case, queue all subsequent 188 * requests in order to maintain ordering. 189 */ 190 if (sc->sc_orphaned || !TAILQ_EMPTY(&sc->sc_queue)) { 191 G_MOUNTVER_LOGREQ(bp, "Queueing request."); 192 g_mountver_queue(bp); 193 if (!sc->sc_orphaned) 194 g_mountver_send_queued(gp); 195 } else { 196 G_MOUNTVER_LOGREQ(bp, "Sending request."); 197 g_mountver_send(bp); 198 } 199} 200 201static int 202g_mountver_access(struct g_provider *pp, int dr, int dw, int de) 203{ 204 struct g_mountver_softc *sc; 205 struct g_geom *gp; 206 struct g_consumer *cp; 207 208 g_topology_assert(); 209 210 gp = pp->geom; 211 cp = LIST_FIRST(&gp->consumer); 212 sc = gp->softc; 213 if (sc == NULL && dr <= 0 && dw <= 0 && de <= 0) 214 return (0); 215 KASSERT(sc != NULL, ("Trying to access withered provider \"%s\".", pp->name)); 216 217 sc->sc_access_r += dr; 218 sc->sc_access_w += dw; 219 sc->sc_access_e += de; 220 221 if (sc->sc_orphaned) 222 return (0); 223 224 return (g_access(cp, dr, dw, de)); 225} 226 227static int 228g_mountver_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp) 229{ 230 struct g_mountver_softc *sc; 231 struct g_geom *gp; 232 struct g_provider *newpp; 233 struct g_consumer *cp; 234 char name[64]; 235 int error; 236 int identsize = DISK_IDENT_SIZE; 237 238 g_topology_assert(); 239 240 gp = NULL; 241 newpp = NULL; 242 cp = NULL; 243 244 snprintf(name, sizeof(name), "%s%s", pp->name, G_MOUNTVER_SUFFIX); 245 LIST_FOREACH(gp, &mp->geom, geom) { 246 if (strcmp(gp->name, name) == 0) { 247 gctl_error(req, "Provider %s already exists.", name); 248 return (EEXIST); 249 } 250 } 251 gp = g_new_geomf(mp, name); 252 sc = g_malloc(sizeof(*sc), M_WAITOK | M_ZERO); 253 mtx_init(&sc->sc_mtx, "gmountver", NULL, MTX_DEF); 254 TAILQ_INIT(&sc->sc_queue); 255 sc->sc_provider_name = strdup(pp->name, M_GEOM); 256 gp->softc = sc; 257 gp->start = g_mountver_start; 258 gp->orphan = g_mountver_orphan; 259 gp->access = g_mountver_access; 260 gp->dumpconf = g_mountver_dumpconf; 261 262 newpp = g_new_providerf(gp, gp->name); 263 newpp->mediasize = pp->mediasize; 264 newpp->sectorsize = pp->sectorsize; 265 266 cp = g_new_consumer(gp); 267 error = g_attach(cp, pp); 268 if (error != 0) { 269 gctl_error(req, "Cannot attach to provider %s.", pp->name); 270 goto fail; 271 } 272 error = g_access(cp, 1, 0, 0); 273 if (error != 0) { 274 gctl_error(req, "Cannot access provider %s.", pp->name); 275 goto fail; 276 } 277 error = g_io_getattr("GEOM::ident", cp, &identsize, sc->sc_ident); 278 g_access(cp, -1, 0, 0); 279 if (error != 0) { 280 if (g_mountver_check_ident) { 281 gctl_error(req, "Cannot get disk ident from %s; error = %d.", pp->name, error); 282 goto fail; 283 } 284 285 G_MOUNTVER_DEBUG(0, "Cannot get disk ident from %s; error = %d.", pp->name, error); 286 sc->sc_ident[0] = '\0'; 287 } 288 289 g_error_provider(newpp, 0); 290 G_MOUNTVER_DEBUG(0, "Device %s created.", gp->name); 291 return (0); 292fail: 293 g_free(sc->sc_provider_name); 294 if (cp->provider != NULL) 295 g_detach(cp); 296 g_destroy_consumer(cp); 297 g_destroy_provider(newpp); 298 g_free(gp->softc); 299 g_destroy_geom(gp); 300 return (error); 301} 302 303static int 304g_mountver_destroy(struct g_geom *gp, boolean_t force) 305{ 306 struct g_mountver_softc *sc; 307 struct g_provider *pp; 308 309 g_topology_assert(); 310 if (gp->softc == NULL) 311 return (ENXIO); 312 sc = gp->softc; 313 pp = LIST_FIRST(&gp->provider); 314 if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) { 315 if (force) { 316 G_MOUNTVER_DEBUG(0, "Device %s is still open, so it " 317 "can't be definitely removed.", pp->name); 318 } else { 319 G_MOUNTVER_DEBUG(1, "Device %s is still open (r%dw%de%d).", 320 pp->name, pp->acr, pp->acw, pp->ace); 321 return (EBUSY); 322 } 323 } else { 324 G_MOUNTVER_DEBUG(0, "Device %s removed.", gp->name); 325 } 326 if (pp != NULL) 327 g_orphan_provider(pp, ENXIO); 328 g_mountver_discard_queued(gp); 329 g_free(sc->sc_provider_name); 330 g_free(gp->softc); 331 gp->softc = NULL; 332 g_wither_geom(gp, ENXIO); 333 334 return (0); 335} 336 337static int 338g_mountver_destroy_geom(struct gctl_req *req, struct g_class *mp, struct g_geom *gp) 339{ 340 341 return (g_mountver_destroy(gp, 0)); 342} 343 344static void 345g_mountver_ctl_create(struct gctl_req *req, struct g_class *mp) 346{ 347 struct g_provider *pp; 348 const char *name; 349 char param[16]; 350 int i, *nargs; 351 352 g_topology_assert(); 353 354 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs)); 355 if (nargs == NULL) { 356 gctl_error(req, "No '%s' argument", "nargs"); 357 return; 358 } 359 if (*nargs <= 0) { 360 gctl_error(req, "Missing device(s)."); 361 return; 362 } 363 for (i = 0; i < *nargs; i++) { 364 snprintf(param, sizeof(param), "arg%d", i); 365 name = gctl_get_asciiparam(req, param); 366 if (name == NULL) { 367 gctl_error(req, "No 'arg%d' argument", i); 368 return; 369 } 370 if (strncmp(name, "/dev/", strlen("/dev/")) == 0) 371 name += strlen("/dev/"); 372 pp = g_provider_by_name(name); 373 if (pp == NULL) { 374 G_MOUNTVER_DEBUG(1, "Provider %s is invalid.", name); 375 gctl_error(req, "Provider %s is invalid.", name); 376 return; 377 } 378 if (g_mountver_create(req, mp, pp) != 0) 379 return; 380 } 381} 382 383static struct g_geom * 384g_mountver_find_geom(struct g_class *mp, const char *name) 385{ 386 struct g_geom *gp; 387 388 LIST_FOREACH(gp, &mp->geom, geom) { 389 if (strcmp(gp->name, name) == 0) 390 return (gp); 391 } 392 return (NULL); 393} 394 395static void 396g_mountver_ctl_destroy(struct gctl_req *req, struct g_class *mp) 397{ 398 int *nargs, *force, error, i; 399 struct g_geom *gp; 400 const char *name; 401 char param[16]; 402 403 g_topology_assert(); 404 405 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs)); 406 if (nargs == NULL) { 407 gctl_error(req, "No '%s' argument", "nargs"); 408 return; 409 } 410 if (*nargs <= 0) { 411 gctl_error(req, "Missing device(s)."); 412 return; 413 } 414 force = gctl_get_paraml(req, "force", sizeof(*force)); 415 if (force == NULL) { 416 gctl_error(req, "No 'force' argument"); 417 return; 418 } 419 420 for (i = 0; i < *nargs; i++) { 421 snprintf(param, sizeof(param), "arg%d", i); 422 name = gctl_get_asciiparam(req, param); 423 if (name == NULL) { 424 gctl_error(req, "No 'arg%d' argument", i); 425 return; 426 } 427 if (strncmp(name, "/dev/", strlen("/dev/")) == 0) 428 name += strlen("/dev/"); 429 gp = g_mountver_find_geom(mp, name); 430 if (gp == NULL) { 431 G_MOUNTVER_DEBUG(1, "Device %s is invalid.", name); 432 gctl_error(req, "Device %s is invalid.", name); 433 return; 434 } 435 error = g_mountver_destroy(gp, *force); 436 if (error != 0) { 437 gctl_error(req, "Cannot destroy device %s (error=%d).", 438 gp->name, error); 439 return; 440 } 441 } 442} 443 444static void 445g_mountver_orphan(struct g_consumer *cp) 446{ 447 struct g_mountver_softc *sc; 448 449 g_topology_assert(); 450 451 sc = cp->geom->softc; 452 sc->sc_orphaned = 1; 453 if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0) 454 g_access(cp, -cp->acr, -cp->acw, -cp->ace); 455 g_detach(cp); 456 G_MOUNTVER_DEBUG(0, "%s is offline. Mount verification in progress.", sc->sc_provider_name); 457} 458 459static int 460g_mountver_ident_matches(struct g_geom *gp) 461{ 462 struct g_consumer *cp; 463 struct g_mountver_softc *sc; 464 char ident[DISK_IDENT_SIZE]; 465 int error, identsize = DISK_IDENT_SIZE; 466 467 sc = gp->softc; 468 cp = LIST_FIRST(&gp->consumer); 469 470 if (g_mountver_check_ident == 0) 471 return (0); 472 473 error = g_access(cp, 1, 0, 0); 474 if (error != 0) { 475 G_MOUNTVER_DEBUG(0, "Cannot access %s; " 476 "not attaching; error = %d.", gp->name, error); 477 return (1); 478 } 479 error = g_io_getattr("GEOM::ident", cp, &identsize, ident); 480 g_access(cp, -1, 0, 0); 481 if (error != 0) { 482 G_MOUNTVER_DEBUG(0, "Cannot get disk ident for %s; " 483 "not attaching; error = %d.", gp->name, error); 484 return (1); 485 } 486 if (strcmp(ident, sc->sc_ident) != 0) { 487 G_MOUNTVER_DEBUG(1, "Disk ident for %s (\"%s\") is different " 488 "from expected \"%s\", not attaching.", gp->name, ident, 489 sc->sc_ident); 490 return (1); 491 } 492 493 return (0); 494} 495 496static struct g_geom * 497g_mountver_taste(struct g_class *mp, struct g_provider *pp, int flags __unused) 498{ 499 struct g_mountver_softc *sc; 500 struct g_consumer *cp; 501 struct g_geom *gp; 502 int error; 503 504 g_topology_assert(); 505 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name); 506 G_MOUNTVER_DEBUG(2, "Tasting %s.", pp->name); 507 508 /* 509 * Let's check if device already exists. 510 */ 511 LIST_FOREACH(gp, &mp->geom, geom) { 512 sc = gp->softc; 513 if (sc == NULL) 514 continue; 515 516 /* Already attached? */ 517 if (pp == LIST_FIRST(&gp->provider)) 518 return (NULL); 519 520 if (sc->sc_orphaned && strcmp(pp->name, sc->sc_provider_name) == 0) 521 break; 522 } 523 if (gp == NULL) 524 return (NULL); 525 526 cp = LIST_FIRST(&gp->consumer); 527 g_attach(cp, pp); 528 error = g_mountver_ident_matches(gp); 529 if (error != 0) { 530 g_detach(cp); 531 return (NULL); 532 } 533 if (sc->sc_access_r > 0 || sc->sc_access_w > 0 || sc->sc_access_e > 0) { 534 error = g_access(cp, sc->sc_access_r, sc->sc_access_w, sc->sc_access_e); 535 if (error != 0) { 536 G_MOUNTVER_DEBUG(0, "Cannot access %s; error = %d.", pp->name, error); 537 g_detach(cp); 538 return (NULL); 539 } 540 } 541 g_mountver_send_queued(gp); 542 sc->sc_orphaned = 0; 543 G_MOUNTVER_DEBUG(0, "%s has completed mount verification.", sc->sc_provider_name); 544 545 return (gp); 546} 547 548static void 549g_mountver_config(struct gctl_req *req, struct g_class *mp, const char *verb) 550{ 551 uint32_t *version; 552 553 g_topology_assert(); 554 555 version = gctl_get_paraml(req, "version", sizeof(*version)); 556 if (version == NULL) { 557 gctl_error(req, "No '%s' argument.", "version"); 558 return; 559 } 560 if (*version != G_MOUNTVER_VERSION) { 561 gctl_error(req, "Userland and kernel parts are out of sync."); 562 return; 563 } 564 565 if (strcmp(verb, "create") == 0) { 566 g_mountver_ctl_create(req, mp); 567 return; 568 } else if (strcmp(verb, "destroy") == 0) { 569 g_mountver_ctl_destroy(req, mp); 570 return; 571 } 572 573 gctl_error(req, "Unknown verb."); 574} 575 576static void 577g_mountver_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, 578 struct g_consumer *cp, struct g_provider *pp) 579{ 580 struct g_mountver_softc *sc; 581 582 if (pp != NULL || cp != NULL) 583 return; 584 585 sc = gp->softc; 586 sbuf_printf(sb, "%s<State>%s</State>\n", indent, 587 sc->sc_orphaned ? "OFFLINE" : "ONLINE"); 588 sbuf_printf(sb, "%s<Provider-Name>%s</Provider-Name>\n", indent, sc->sc_provider_name); 589 sbuf_printf(sb, "%s<Disk-Ident>%s</Disk-Ident>\n", indent, sc->sc_ident); 590} 591 592static void 593g_mountver_shutdown_pre_sync(void *arg, int howto) 594{ 595 struct g_class *mp; 596 struct g_geom *gp, *gp2; 597 598 mp = arg; 599 DROP_GIANT(); 600 g_topology_lock(); 601 LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) 602 g_mountver_destroy(gp, 1); 603 g_topology_unlock(); 604 PICKUP_GIANT(); 605} 606 607static void 608g_mountver_init(struct g_class *mp) 609{ 610 611 g_mountver_pre_sync = EVENTHANDLER_REGISTER(shutdown_pre_sync, 612 g_mountver_shutdown_pre_sync, mp, SHUTDOWN_PRI_FIRST); 613 if (g_mountver_pre_sync == NULL) 614 G_MOUNTVER_DEBUG(0, "Warning! Cannot register shutdown event."); 615} 616 617static void 618g_mountver_fini(struct g_class *mp) 619{ 620 621 if (g_mountver_pre_sync != NULL) 622 EVENTHANDLER_DEREGISTER(shutdown_pre_sync, g_mountver_pre_sync); 623} 624 625DECLARE_GEOM_CLASS(g_mountver_class, g_mountver); 626