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sys/geom/virstor/g_virstor.c
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1 /*- 2 * Copyright (c) 2006-2007 Ivan Voras <ivoras@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 /* Implementation notes: 28 * - "Components" are wrappers around providers that make up the 29 * virtual storage (i.e. a virstor has "physical" components) 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/kernel.h> 38 #include <sys/module.h> 39 #include <sys/lock.h> 40 #include <sys/mutex.h> 41 #include <sys/sx.h> 42 #include <sys/bio.h> 43 #include <sys/sysctl.h> 44 #include <sys/malloc.h> 45 #include <sys/time.h> 46 #include <sys/proc.h> 47 #include <sys/kthread.h> 48 #include <sys/mutex.h> 49 #include <vm/uma.h> 50 #include <geom/geom.h> 51 52 #include <geom/virstor/g_virstor.h> 53 #include <geom/virstor/g_virstor_md.h> 54 55 /* Declare malloc(9) label */ 56 static MALLOC_DEFINE(M_GVIRSTOR, "gvirstor", "GEOM_VIRSTOR Data"); 57 58 /* GEOM class methods */ 59 static g_init_t g_virstor_init; 60 static g_fini_t g_virstor_fini; 61 static g_taste_t g_virstor_taste; 62 static g_ctl_req_t g_virstor_config; 63 static g_ctl_destroy_geom_t g_virstor_destroy_geom; 64 65 /* Declare & initialize class structure ("geom class") */ 66 struct g_class g_virstor_class = { 67 .name = G_VIRSTOR_CLASS_NAME, 68 .version = G_VERSION, 69 .init = g_virstor_init, 70 .fini = g_virstor_fini, 71 .taste = g_virstor_taste, 72 .ctlreq = g_virstor_config, 73 .destroy_geom = g_virstor_destroy_geom 74 /* The .dumpconf and the rest are only usable for a geom instance, so 75 * they will be set when such instance is created. */ 76 }; 77 78 /* Declare sysctl's and loader tunables */ 79 SYSCTL_DECL(_kern_geom); 80 SYSCTL_NODE(_kern_geom, OID_AUTO, virstor, CTLFLAG_RW, 0, "GEOM_GVIRSTOR information"); 81 82 static u_int g_virstor_debug = 2; /* XXX: lower to 2 when released to public */ 83 TUNABLE_INT("kern.geom.virstor.debug", &g_virstor_debug); 84 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, debug, CTLFLAG_RW, &g_virstor_debug, 85 0, "Debug level (2=production, 5=normal, 15=excessive)"); 86 87 static u_int g_virstor_chunk_watermark = 100; 88 TUNABLE_INT("kern.geom.virstor.chunk_watermark", &g_virstor_chunk_watermark); 89 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, chunk_watermark, CTLFLAG_RW, 90 &g_virstor_chunk_watermark, 0, 91 "Minimum number of free chunks before issuing administrative warning"); 92 93 static u_int g_virstor_component_watermark = 1; 94 TUNABLE_INT("kern.geom.virstor.component_watermark", 95 &g_virstor_component_watermark); 96 SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, component_watermark, CTLFLAG_RW, 97 &g_virstor_component_watermark, 0, 98 "Minimum number of free components before issuing administrative warning"); 99 100 static int read_metadata(struct g_consumer *, struct g_virstor_metadata *); 101 static int write_metadata(struct g_consumer *, struct g_virstor_metadata *); 102 static int clear_metadata(struct g_virstor_component *); 103 static int add_provider_to_geom(struct g_virstor_softc *, struct g_provider *, 104 struct g_virstor_metadata *); 105 static struct g_geom *create_virstor_geom(struct g_class *, 106 struct g_virstor_metadata *); 107 static void virstor_check_and_run(struct g_virstor_softc *); 108 static u_int virstor_valid_components(struct g_virstor_softc *); 109 static int virstor_geom_destroy(struct g_virstor_softc *, boolean_t, 110 boolean_t); 111 static void remove_component(struct g_virstor_softc *, 112 struct g_virstor_component *, boolean_t); 113 static void bioq_dismantle(struct bio_queue_head *); 114 static int allocate_chunk(struct g_virstor_softc *, 115 struct g_virstor_component **, u_int *, u_int *); 116 static void delay_destroy_consumer(void *, int); 117 static void dump_component(struct g_virstor_component *comp); 118 #if 0 119 static void dump_me(struct virstor_map_entry *me, unsigned int nr); 120 #endif 121 122 static void virstor_ctl_stop(struct gctl_req *, struct g_class *); 123 static void virstor_ctl_add(struct gctl_req *, struct g_class *); 124 static void virstor_ctl_remove(struct gctl_req *, struct g_class *); 125 static struct g_virstor_softc * virstor_find_geom(const struct g_class *, 126 const char *); 127 static void update_metadata(struct g_virstor_softc *); 128 static void fill_metadata(struct g_virstor_softc *, struct g_virstor_metadata *, 129 u_int, u_int); 130 131 static void g_virstor_orphan(struct g_consumer *); 132 static int g_virstor_access(struct g_provider *, int, int, int); 133 static void g_virstor_start(struct bio *); 134 static void g_virstor_dumpconf(struct sbuf *, const char *, struct g_geom *, 135 struct g_consumer *, struct g_provider *); 136 static void g_virstor_done(struct bio *); 137 138 static void invalid_call(void); 139 /* 140 * Initialise GEOM class (per-class callback) 141 */ 142 static void 143 g_virstor_init(struct g_class *mp __unused) 144 { 145 146 /* Catch map struct size mismatch at compile time; Map entries must 147 * fit into MAXPHYS exactly, with no wasted space. */ 148 CTASSERT(VIRSTOR_MAP_BLOCK_ENTRIES*VIRSTOR_MAP_ENTRY_SIZE == MAXPHYS); 149 150 /* Init UMA zones, TAILQ's, other global vars */ 151 } 152 153 /* 154 * Finalise GEOM class (per-class callback) 155 */ 156 static void 157 g_virstor_fini(struct g_class *mp __unused) 158 { 159 160 /* Deinit UMA zones & global vars */ 161 } 162 163 /* 164 * Config (per-class callback) 165 */ 166 static void 167 g_virstor_config(struct gctl_req *req, struct g_class *cp, char const *verb) 168 { 169 uint32_t *version; 170 171 g_topology_assert(); 172 173 version = gctl_get_paraml(req, "version", sizeof(*version)); 174 if (version == NULL) { 175 gctl_error(req, "Failed to get 'version' argument"); 176 return; 177 } 178 if (*version != G_VIRSTOR_VERSION) { 179 gctl_error(req, "Userland and kernel versions out of sync"); 180 return; 181 } 182 183 g_topology_unlock(); 184 if (strcmp(verb, "add") == 0) 185 virstor_ctl_add(req, cp); 186 else if (strcmp(verb, "stop") == 0 || strcmp(verb, "destroy") == 0) 187 virstor_ctl_stop(req, cp); 188 else if (strcmp(verb, "remove") == 0) 189 virstor_ctl_remove(req, cp); 190 else 191 gctl_error(req, "unknown verb: '%s'", verb); 192 g_topology_lock(); 193 } 194 195 /* 196 * "stop" verb from userland 197 */ 198 static void 199 virstor_ctl_stop(struct gctl_req *req, struct g_class *cp) 200 { 201 int *force, *nargs; 202 int i; 203 204 nargs = gctl_get_paraml(req, "nargs", sizeof *nargs); 205 if (nargs == NULL) { 206 gctl_error(req, "Error fetching argument '%s'", "nargs"); 207 return; 208 } 209 if (*nargs < 1) { 210 gctl_error(req, "Invalid number of arguments"); 211 return; 212 } 213 force = gctl_get_paraml(req, "force", sizeof *force); 214 if (force == NULL) { 215 gctl_error(req, "Error fetching argument '%s'", "force"); 216 return; 217 } 218 219 g_topology_lock(); 220 for (i = 0; i < *nargs; i++) { 221 char param[8]; 222 const char *name; 223 struct g_virstor_softc *sc; 224 int error; 225 226 sprintf(param, "arg%d", i); 227 name = gctl_get_asciiparam(req, param); 228 sc = virstor_find_geom(cp, name); 229 LOG_MSG(LVL_INFO, "Stopping %s by the userland command", 230 sc->geom->name); 231 update_metadata(sc); 232 if ((error = virstor_geom_destroy(sc, TRUE, TRUE)) != 0) { 233 LOG_MSG(LVL_ERROR, "Cannot destroy %s: %d", 234 sc->geom->name, error); 235 } 236 } 237 g_topology_unlock(); 238 } 239 240 /* 241 * "add" verb from userland - add new component(s) to the structure. 242 * This will be done all at once in here, without going through the 243 * .taste function for new components. 244 */ 245 static void 246 virstor_ctl_add(struct gctl_req *req, struct g_class *cp) 247 { 248 /* Note: while this is going on, I/O is being done on 249 * the g_up and g_down threads. The idea is to make changes 250 * to softc members in a way that can atomically activate 251 * them all at once. */ 252 struct g_virstor_softc *sc; 253 int *hardcode, *nargs; 254 const char *geom_name; /* geom to add a component to */ 255 struct g_consumer *fcp; 256 struct g_virstor_bio_q *bq; 257 u_int added; 258 int error; 259 int i; 260 261 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs)); 262 if (nargs == NULL) { 263 gctl_error(req, "Error fetching argument '%s'", "nargs"); 264 return; 265 } 266 if (*nargs < 2) { 267 gctl_error(req, "Invalid number of arguments"); 268 return; 269 } 270 hardcode = gctl_get_paraml(req, "hardcode", sizeof(*hardcode)); 271 if (hardcode == NULL) { 272 gctl_error(req, "Error fetching argument '%s'", "hardcode"); 273 return; 274 } 275 276 /* Find "our" geom */ 277 geom_name = gctl_get_asciiparam(req, "arg0"); 278 if (geom_name == NULL) { 279 gctl_error(req, "Error fetching argument '%s'", "geom_name (arg0)"); 280 return; 281 } 282 sc = virstor_find_geom(cp, geom_name); 283 if (sc == NULL) { 284 gctl_error(req, "Don't know anything about '%s'", geom_name); 285 return; 286 } 287 288 if (virstor_valid_components(sc) != sc->n_components) { 289 LOG_MSG(LVL_ERROR, "Cannot add components to incomplete " 290 "virstor %s", sc->geom->name); 291 gctl_error(req, "Virstor %s is incomplete", sc->geom->name); 292 return; 293 } 294 295 fcp = sc->components[0].gcons; 296 added = 0; 297 g_topology_lock(); 298 for (i = 1; i < *nargs; i++) { 299 struct g_virstor_metadata md; 300 char aname[8]; 301 const char *prov_name; 302 struct g_provider *pp; 303 struct g_consumer *cp; 304 u_int nc; 305 u_int j; 306 307 snprintf(aname, sizeof aname, "arg%d", i); 308 prov_name = gctl_get_asciiparam(req, aname); 309 if (strncmp(prov_name, _PATH_DEV, strlen(_PATH_DEV)) == 0) 310 prov_name += strlen(_PATH_DEV); 311 312 pp = g_provider_by_name(prov_name); 313 if (pp == NULL) { 314 /* This is the most common error so be verbose about it */ 315 if (added != 0) { 316 gctl_error(req, "Invalid provider: '%s' (added" 317 " %u components)", prov_name, added); 318 update_metadata(sc); 319 } else { 320 gctl_error(req, "Invalid provider: '%s'", 321 prov_name); 322 } 323 g_topology_unlock(); 324 return; 325 } 326 cp = g_new_consumer(sc->geom); 327 if (cp == NULL) { 328 gctl_error(req, "Cannot create consumer"); 329 g_topology_unlock(); 330 return; 331 } 332 error = g_attach(cp, pp); 333 if (error != 0) { 334 gctl_error(req, "Cannot attach a consumer to %s", 335 pp->name); 336 g_destroy_consumer(cp); 337 g_topology_unlock(); 338 return; 339 } 340 if (fcp->acr != 0 || fcp->acw != 0 || fcp->ace != 0) { 341 error = g_access(cp, fcp->acr, fcp->acw, fcp->ace); 342 if (error != 0) { 343 gctl_error(req, "Access request failed for %s", 344 pp->name); 345 g_destroy_consumer(cp); 346 g_topology_unlock(); 347 return; 348 } 349 } 350 if (fcp->provider->sectorsize != pp->sectorsize) { 351 gctl_error(req, "Sector size doesn't fit for %s", 352 pp->name); 353 g_destroy_consumer(cp); 354 g_topology_unlock(); 355 return; 356 } 357 for (j = 0; j < sc->n_components; j++) { 358 if (strcmp(sc->components[j].gcons->provider->name, 359 pp->name) == 0) { 360 gctl_error(req, "Component %s already in %s", 361 pp->name, sc->geom->name); 362 g_destroy_consumer(cp); 363 g_topology_unlock(); 364 return; 365 } 366 } 367 sc->components = realloc(sc->components, 368 sizeof(*sc->components) * (sc->n_components + 1), 369 M_GVIRSTOR, M_WAITOK); 370 371 nc = sc->n_components; 372 sc->components[nc].gcons = cp; 373 sc->components[nc].sc = sc; 374 sc->components[nc].index = nc; 375 sc->components[nc].chunk_count = cp->provider->mediasize / 376 sc->chunk_size; 377 sc->components[nc].chunk_next = 0; 378 sc->components[nc].chunk_reserved = 0; 379 380 if (sc->components[nc].chunk_count < 4) { 381 gctl_error(req, "Provider too small: %s", 382 cp->provider->name); 383 g_destroy_consumer(cp); 384 g_topology_unlock(); 385 return; 386 } 387 fill_metadata(sc, &md, nc, *hardcode); 388 write_metadata(cp, &md); 389 /* The new component becomes visible when n_components is 390 * incremented */ 391 sc->n_components++; 392 added++; 393 394 } 395 /* This call to update_metadata() is critical. In case there's a 396 * power failure in the middle of it and some components are updated 397 * while others are not, there will be trouble on next .taste() iff 398 * a non-updated component is detected first */ 399 update_metadata(sc); 400 g_topology_unlock(); 401 LOG_MSG(LVL_INFO, "Added %d component(s) to %s", added, 402 sc->geom->name); 403 /* Fire off BIOs previously queued because there wasn't any 404 * physical space left. If the BIOs still can't be satisfied 405 * they will again be added to the end of the queue (during 406 * which the mutex will be recursed) */ 407 bq = malloc(sizeof(*bq), M_GVIRSTOR, M_WAITOK); 408 bq->bio = NULL; 409 mtx_lock(&sc->delayed_bio_q_mtx); 410 /* First, insert a sentinel to the queue end, so we don't 411 * end up in an infinite loop if there's still no free 412 * space available. */ 413 STAILQ_INSERT_TAIL(&sc->delayed_bio_q, bq, linkage); 414 while (!STAILQ_EMPTY(&sc->delayed_bio_q)) { 415 bq = STAILQ_FIRST(&sc->delayed_bio_q); 416 if (bq->bio != NULL) { 417 g_virstor_start(bq->bio); 418 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage); 419 free(bq, M_GVIRSTOR); 420 } else { 421 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage); 422 free(bq, M_GVIRSTOR); 423 break; 424 } 425 } 426 mtx_unlock(&sc->delayed_bio_q_mtx); 427 428 } 429 430 /* 431 * Find a geom handled by the class 432 */ 433 static struct g_virstor_softc * 434 virstor_find_geom(const struct g_class *cp, const char *name) 435 { 436 struct g_geom *gp; 437 438 LIST_FOREACH(gp, &cp->geom, geom) { 439 if (strcmp(name, gp->name) == 0) 440 return (gp->softc); 441 } 442 return (NULL); 443 } 444 445 /* 446 * Update metadata on all components to reflect the current state 447 * of these fields: 448 * - chunk_next 449 * - flags 450 * - md_count 451 * Expects things to be set up so write_metadata() can work, i.e. 452 * the topology lock must be held. 453 */ 454 static void 455 update_metadata(struct g_virstor_softc *sc) 456 { 457 struct g_virstor_metadata md; 458 int n; 459 460 if (virstor_valid_components(sc) != sc->n_components) 461 return; /* Incomplete device */ 462 LOG_MSG(LVL_DEBUG, "Updating metadata on components for %s", 463 sc->geom->name); 464 /* Update metadata on components */ 465 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, 466 sc->geom->class->name, sc->geom->name); 467 g_topology_assert(); 468 for (n = 0; n < sc->n_components; n++) { 469 read_metadata(sc->components[n].gcons, &md); 470 md.chunk_next = sc->components[n].chunk_next; 471 md.flags = sc->components[n].flags; 472 md.md_count = sc->n_components; 473 write_metadata(sc->components[n].gcons, &md); 474 } 475 } 476 477 /* 478 * Fills metadata (struct md) from information stored in softc and the nc'th 479 * component of virstor 480 */ 481 static void 482 fill_metadata(struct g_virstor_softc *sc, struct g_virstor_metadata *md, 483 u_int nc, u_int hardcode) 484 { 485 struct g_virstor_component *c; 486 487 bzero(md, sizeof *md); 488 c = &sc->components[nc]; 489 490 strncpy(md->md_magic, G_VIRSTOR_MAGIC, sizeof md->md_magic); 491 md->md_version = G_VIRSTOR_VERSION; 492 strncpy(md->md_name, sc->geom->name, sizeof md->md_name); 493 md->md_id = sc->id; 494 md->md_virsize = sc->virsize; 495 md->md_chunk_size = sc->chunk_size; 496 md->md_count = sc->n_components; 497 498 if (hardcode) { 499 strncpy(md->provider, c->gcons->provider->name, 500 sizeof md->provider); 501 } 502 md->no = nc; 503 md->provsize = c->gcons->provider->mediasize; 504 md->chunk_count = c->chunk_count; 505 md->chunk_next = c->chunk_next; 506 md->chunk_reserved = c->chunk_reserved; 507 md->flags = c->flags; 508 } 509 510 /* 511 * Remove a component from virstor device. 512 * Can only be done if the component is unallocated. 513 */ 514 static void 515 virstor_ctl_remove(struct gctl_req *req, struct g_class *cp) 516 { 517 /* As this is executed in parallel to I/O, operations on virstor 518 * structures must be as atomic as possible. */ 519 struct g_virstor_softc *sc; 520 int *nargs; 521 const char *geom_name; 522 u_int removed; 523 int i; 524 525 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs)); 526 if (nargs == NULL) { 527 gctl_error(req, "Error fetching argument '%s'", "nargs"); 528 return; 529 } 530 if (*nargs < 2) { 531 gctl_error(req, "Invalid number of arguments"); 532 return; 533 } 534 /* Find "our" geom */ 535 geom_name = gctl_get_asciiparam(req, "arg0"); 536 if (geom_name == NULL) { 537 gctl_error(req, "Error fetching argument '%s'", 538 "geom_name (arg0)"); 539 return; 540 } 541 sc = virstor_find_geom(cp, geom_name); 542 if (sc == NULL) { 543 gctl_error(req, "Don't know anything about '%s'", geom_name); 544 return; 545 } 546 547 if (virstor_valid_components(sc) != sc->n_components) { 548 LOG_MSG(LVL_ERROR, "Cannot remove components from incomplete " 549 "virstor %s", sc->geom->name); 550 gctl_error(req, "Virstor %s is incomplete", sc->geom->name); 551 return; 552 } 553 554 removed = 0; 555 for (i = 1; i < *nargs; i++) { 556 char param[8]; 557 const char *prov_name; 558 int j, found; 559 struct g_virstor_component *newcomp, *compbak; 560 561 sprintf(param, "arg%d", i); 562 prov_name = gctl_get_asciiparam(req, param); 563 if (strncmp(prov_name, _PATH_DEV, strlen(_PATH_DEV)) == 0) 564 prov_name += strlen(_PATH_DEV); 565 566 found = -1; 567 for (j = 0; j < sc->n_components; j++) { 568 if (strcmp(sc->components[j].gcons->provider->name, 569 prov_name) == 0) { 570 found = j; 571 break; 572 } 573 } 574 if (found == -1) { 575 LOG_MSG(LVL_ERROR, "No %s component in %s", 576 prov_name, sc->geom->name); 577 continue; 578 } 579 580 compbak = sc->components; 581 newcomp = malloc(sc->n_components * sizeof(*sc->components), 582 M_GVIRSTOR, M_WAITOK | M_ZERO); 583 bcopy(sc->components, newcomp, found * sizeof(*sc->components)); 584 bcopy(&sc->components[found + 1], newcomp + found, 585 found * sizeof(*sc->components)); 586 if ((sc->components[j].flags & VIRSTOR_PROVIDER_ALLOCATED) != 0) { 587 LOG_MSG(LVL_ERROR, "Allocated provider %s cannot be " 588 "removed from %s", 589 prov_name, sc->geom->name); 590 free(newcomp, M_GVIRSTOR); 591 /* We'll consider this non-fatal error */ 592 continue; 593 } 594 /* Renumerate unallocated components */ 595 for (j = 0; j < sc->n_components-1; j++) { 596 if ((sc->components[j].flags & 597 VIRSTOR_PROVIDER_ALLOCATED) == 0) { 598 sc->components[j].index = j; 599 } 600 } 601 /* This is the critical section. If a component allocation 602 * event happens while both variables are not yet set, 603 * there will be trouble. Something will panic on encountering 604 * NULL sc->components[x].gcomp member. 605 * Luckily, component allocation happens very rarely and 606 * removing components is an abnormal action in any case. */ 607 sc->components = newcomp; 608 sc->n_components--; 609 /* End critical section */ 610 611 g_topology_lock(); 612 if (clear_metadata(&compbak[found]) != 0) { 613 LOG_MSG(LVL_WARNING, "Trouble ahead: cannot clear " 614 "metadata on %s", prov_name); 615 } 616 g_detach(compbak[found].gcons); 617 g_destroy_consumer(compbak[found].gcons); 618 g_topology_unlock(); 619 620 free(compbak, M_GVIRSTOR); 621 622 removed++; 623 } 624 625 /* This call to update_metadata() is critical. In case there's a 626 * power failure in the middle of it and some components are updated 627 * while others are not, there will be trouble on next .taste() iff 628 * a non-updated component is detected first */ 629 g_topology_lock(); 630 update_metadata(sc); 631 g_topology_unlock(); 632 LOG_MSG(LVL_INFO, "Removed %d component(s) from %s", removed, 633 sc->geom->name); 634 } 635 636 /* 637 * Clear metadata sector on component 638 */ 639 static int 640 clear_metadata(struct g_virstor_component *comp) 641 { 642 char *buf; 643 int error; 644 645 LOG_MSG(LVL_INFO, "Clearing metadata on %s", 646 comp->gcons->provider->name); 647 g_topology_assert(); 648 error = g_access(comp->gcons, 0, 1, 0); 649 if (error != 0) 650 return (error); 651 buf = malloc(comp->gcons->provider->sectorsize, M_GVIRSTOR, 652 M_WAITOK | M_ZERO); 653 error = g_write_data(comp->gcons, 654 comp->gcons->provider->mediasize - 655 comp->gcons->provider->sectorsize, 656 buf, 657 comp->gcons->provider->sectorsize); 658 free(buf, M_GVIRSTOR); 659 g_access(comp->gcons, 0, -1, 0); 660 return (error); 661 } 662 663 /* 664 * Destroy geom forcibly. 665 */ 666 static int 667 g_virstor_destroy_geom(struct gctl_req *req __unused, struct g_class *mp, 668 struct g_geom *gp) 669 { 670 struct g_virstor_softc *sc; 671 int exitval; 672 673 sc = gp->softc; 674 KASSERT(sc != NULL, ("%s: NULL sc", __func__)); 675 676 exitval = 0; 677 LOG_MSG(LVL_DEBUG, "%s called for %s, sc=%p", __func__, gp->name, 678 gp->softc); 679 680 if (sc != NULL) { 681 #ifdef INVARIANTS 682 char *buf; 683 int error; 684 off_t off; 685 int isclean, count; 686 int n; 687 688 LOG_MSG(LVL_INFO, "INVARIANTS detected"); 689 LOG_MSG(LVL_INFO, "Verifying allocation " 690 "table for %s", sc->geom->name); 691 count = 0; 692 for (n = 0; n < sc->chunk_count; n++) { 693 if (sc->map[n].flags || VIRSTOR_MAP_ALLOCATED != 0) 694 count++; 695 } 696 LOG_MSG(LVL_INFO, "Device %s has %d allocated chunks", 697 sc->geom->name, count); 698 n = off = count = 0; 699 isclean = 1; 700 if (virstor_valid_components(sc) != sc->n_components) { 701 /* This is a incomplete virstor device (not all 702 * components have been found) */ 703 LOG_MSG(LVL_ERROR, "Device %s is incomplete", 704 sc->geom->name); 705 goto bailout; 706 } 707 error = g_access(sc->components[0].gcons, 1, 0, 0); 708 KASSERT(error == 0, ("%s: g_access failed (%d)", __func__, 709 error)); 710 /* Compare the whole on-disk allocation table with what's 711 * currently in memory */ 712 while (n < sc->chunk_count) { 713 buf = g_read_data(sc->components[0].gcons, off, 714 sc->sectorsize, &error); 715 KASSERT(buf != NULL, ("g_read_data returned NULL (%d) " 716 "for read at %jd", error, off)); 717 if (bcmp(buf, &sc->map[n], sc->sectorsize) != 0) { 718 LOG_MSG(LVL_ERROR, "ERROR in allocation table, " 719 "entry %d, offset %jd", n, off); 720 isclean = 0; 721 count++; 722 } 723 n += sc->me_per_sector; 724 off += sc->sectorsize; 725 g_free(buf); 726 } 727 error = g_access(sc->components[0].gcons, -1, 0, 0); 728 KASSERT(error == 0, ("%s: g_access failed (%d) on exit", 729 __func__, error)); 730 if (isclean != 1) { 731 LOG_MSG(LVL_ERROR, "ALLOCATION TABLE CORRUPTED FOR %s " 732 "(%d sectors don't match, max %zu allocations)", 733 sc->geom->name, count, 734 count * sc->me_per_sector); 735 } else { 736 LOG_MSG(LVL_INFO, "Allocation table ok for %s", 737 sc->geom->name); 738 } 739 bailout: 740 #endif 741 update_metadata(sc); 742 virstor_geom_destroy(sc, FALSE, FALSE); 743 exitval = EAGAIN; 744 } else 745 exitval = 0; 746 return (exitval); 747 } 748 749 /* 750 * Taste event (per-class callback) 751 * Examines a provider and creates geom instances if needed 752 */ 753 static struct g_geom * 754 g_virstor_taste(struct g_class *mp, struct g_provider *pp, int flags) 755 { 756 struct g_virstor_metadata md; 757 struct g_geom *gp; 758 struct g_consumer *cp; 759 struct g_virstor_softc *sc; 760 int error; 761 762 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name); 763 g_topology_assert(); 764 LOG_MSG(LVL_DEBUG, "Tasting %s", pp->name); 765 766 /* We need a dummy geom to attach a consumer to the given provider */ 767 gp = g_new_geomf(mp, "virstor:taste.helper"); 768 gp->start = (void *)invalid_call; /* XXX: hacked up so the */ 769 gp->access = (void *)invalid_call; /* compiler doesn't complain. */ 770 gp->orphan = (void *)invalid_call; /* I really want these to fail. */ 771 772 cp = g_new_consumer(gp); 773 g_attach(cp, pp); 774 error = read_metadata(cp, &md); 775 g_detach(cp); 776 g_destroy_consumer(cp); 777 g_destroy_geom(gp); 778 779 if (error != 0) 780 return (NULL); 781 782 if (strcmp(md.md_magic, G_VIRSTOR_MAGIC) != 0) 783 return (NULL); 784 if (md.md_version != G_VIRSTOR_VERSION) { 785 LOG_MSG(LVL_ERROR, "Kernel module version invalid " 786 "to handle %s (%s) : %d should be %d", 787 md.md_name, pp->name, md.md_version, G_VIRSTOR_VERSION); 788 return (NULL); 789 } 790 if (md.provsize != pp->mediasize) 791 return (NULL); 792 793 /* If the provider name is hardcoded, use the offered provider only 794 * if it's been offered with its proper name (the one used in 795 * the label command). */ 796 if (md.provider[0] != '\0') { 797 if (strcmp(md.provider, pp->name) != 0) 798 return (NULL); 799 } 800 801 /* Iterate all geoms this class already knows about to see if a new 802 * geom instance of this class needs to be created (in case the provider 803 * is first from a (possibly) multi-consumer geom) or it just needs 804 * to be added to an existing instance. */ 805 sc = NULL; 806 gp = NULL; 807 LIST_FOREACH(gp, &mp->geom, geom) { 808 sc = gp->softc; 809 if (sc == NULL) 810 continue; 811 if (strcmp(md.md_name, sc->geom->name) != 0) 812 continue; 813 if (md.md_id != sc->id) 814 continue; 815 break; 816 } 817 if (gp != NULL) { /* We found an existing geom instance; add to it */ 818 LOG_MSG(LVL_INFO, "Adding %s to %s", pp->name, md.md_name); 819 error = add_provider_to_geom(sc, pp, &md); 820 if (error != 0) { 821 LOG_MSG(LVL_ERROR, "Error adding %s to %s (error %d)", 822 pp->name, md.md_name, error); 823 return (NULL); 824 } 825 } else { /* New geom instance needs to be created */ 826 gp = create_virstor_geom(mp, &md); 827 if (gp == NULL) { 828 LOG_MSG(LVL_ERROR, "Error creating new instance of " 829 "class %s: %s", mp->name, md.md_name); 830 LOG_MSG(LVL_DEBUG, "Error creating %s at %s", 831 md.md_name, pp->name); 832 return (NULL); 833 } 834 sc = gp->softc; 835 LOG_MSG(LVL_INFO, "Adding %s to %s (first found)", pp->name, 836 md.md_name); 837 error = add_provider_to_geom(sc, pp, &md); 838 if (error != 0) { 839 LOG_MSG(LVL_ERROR, "Error adding %s to %s (error %d)", 840 pp->name, md.md_name, error); 841 virstor_geom_destroy(sc, TRUE, FALSE); 842 return (NULL); 843 } 844 } 845 846 return (gp); 847 } 848 849 /* 850 * Destroyes consumer passed to it in arguments. Used as a callback 851 * on g_event queue. 852 */ 853 static void 854 delay_destroy_consumer(void *arg, int flags __unused) 855 { 856 struct g_consumer *c = arg; 857 KASSERT(c != NULL, ("%s: invalid consumer", __func__)); 858 LOG_MSG(LVL_DEBUG, "Consumer %s destroyed with delay", 859 c->provider->name); 860 g_detach(c); 861 g_destroy_consumer(c); 862 } 863 864 /* 865 * Remove a component (consumer) from geom instance; If it's the first 866 * component being removed, orphan the provider to announce geom's being 867 * dismantled 868 */ 869 static void 870 remove_component(struct g_virstor_softc *sc, struct g_virstor_component *comp, 871 boolean_t delay) 872 { 873 struct g_consumer *c; 874 875 KASSERT(comp->gcons != NULL, ("Component with no consumer in %s", 876 sc->geom->name)); 877 c = comp->gcons; 878 879 comp->gcons = NULL; 880 KASSERT(c->provider != NULL, ("%s: no provider", __func__)); 881 LOG_MSG(LVL_DEBUG, "Component %s removed from %s", c->provider->name, 882 sc->geom->name); 883 if (sc->provider != NULL) { 884 /* Whither, GEOM? */ 885 sc->provider->flags |= G_PF_WITHER; 886 g_orphan_provider(sc->provider, ENXIO); 887 sc->provider = NULL; 888 LOG_MSG(LVL_INFO, "Removing provider %s", sc->geom->name); 889 } 890 891 if (c->acr > 0 || c->acw > 0 || c->ace > 0) 892 g_access(c, -c->acr, -c->acw, -c->ace); 893 if (delay) { 894 /* Destroy consumer after it's tasted */ 895 g_post_event(delay_destroy_consumer, c, M_WAITOK, NULL); 896 } else { 897 g_detach(c); 898 g_destroy_consumer(c); 899 } 900 } 901 902 /* 903 * Destroy geom - called internally 904 * See g_virstor_destroy_geom for the other one 905 */ 906 static int 907 virstor_geom_destroy(struct g_virstor_softc *sc, boolean_t force, 908 boolean_t delay) 909 { 910 struct g_provider *pp; 911 struct g_geom *gp; 912 int n; 913 914 g_topology_assert(); 915 916 if (sc == NULL) 917 return (ENXIO); 918 919 pp = sc->provider; 920 if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) { 921 LOG_MSG(force ? LVL_WARNING : LVL_ERROR, 922 "Device %s is still open.", pp->name); 923 if (!force) 924 return (EBUSY); 925 } 926 927 for (n = 0; n < sc->n_components; n++) { 928 if (sc->components[n].gcons != NULL) 929 remove_component(sc, &sc->components[n], delay); 930 } 931 932 gp = sc->geom; 933 gp->softc = NULL; 934 935 KASSERT(sc->provider == NULL, ("Provider still exists for %s", 936 gp->name)); 937 938 /* XXX: This might or might not work, since we're called with 939 * the topology lock held. Also, it might panic the kernel if 940 * the error'd BIO is in softupdates code. */ 941 mtx_lock(&sc->delayed_bio_q_mtx); 942 while (!STAILQ_EMPTY(&sc->delayed_bio_q)) { 943 struct g_virstor_bio_q *bq; 944 bq = STAILQ_FIRST(&sc->delayed_bio_q); 945 bq->bio->bio_error = ENOSPC; 946 g_io_deliver(bq->bio, EIO); 947 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage); 948 free(bq, M_GVIRSTOR); 949 } 950 mtx_unlock(&sc->delayed_bio_q_mtx); 951 mtx_destroy(&sc->delayed_bio_q_mtx); 952 953 free(sc->map, M_GVIRSTOR); 954 free(sc->components, M_GVIRSTOR); 955 bzero(sc, sizeof *sc); 956 free(sc, M_GVIRSTOR); 957 958 pp = LIST_FIRST(&gp->provider); /* We only offer one provider */ 959 if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)) 960 LOG_MSG(LVL_DEBUG, "Device %s destroyed", gp->name); 961 962 g_wither_geom(gp, ENXIO); 963 964 return (0); 965 } 966 967 /* 968 * Utility function: read metadata & decode. Wants topology lock to be 969 * held. 970 */ 971 static int 972 read_metadata(struct g_consumer *cp, struct g_virstor_metadata *md) 973 { 974 struct g_provider *pp; 975 char *buf; 976 int error; 977 978 g_topology_assert(); 979 error = g_access(cp, 1, 0, 0); 980 if (error != 0) 981 return (error); 982 pp = cp->provider; 983 g_topology_unlock(); 984 buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize, 985 &error); 986 g_topology_lock(); 987 g_access(cp, -1, 0, 0); 988 if (buf == NULL) 989 return (error); 990 991 virstor_metadata_decode(buf, md); 992 g_free(buf); 993 994 return (0); 995 } 996 997 /** 998 * Utility function: encode & write metadata. Assumes topology lock is 999 * held. 1000 */ 1001 static int 1002 write_metadata(struct g_consumer *cp, struct g_virstor_metadata *md) 1003 { 1004 struct g_provider *pp; 1005 char *buf; 1006 int error; 1007 1008 KASSERT(cp != NULL && md != NULL && cp->provider != NULL, 1009 ("Something's fishy in %s", __func__)); 1010 LOG_MSG(LVL_DEBUG, "Writing metadata on %s", cp->provider->name); 1011 g_topology_assert(); 1012 error = g_access(cp, 0, 1, 0); 1013 if (error != 0) 1014 return (error); 1015 pp = cp->provider; 1016 1017 buf = malloc(pp->sectorsize, M_GVIRSTOR, M_WAITOK); 1018 virstor_metadata_encode(md, buf); 1019 g_topology_unlock(); 1020 error = g_write_data(cp, pp->mediasize - pp->sectorsize, buf, 1021 pp->sectorsize); 1022 g_topology_lock(); 1023 g_access(cp, 0, -1, 0); 1024 1025 free(buf, M_GVIRSTOR); 1026 return (0); 1027 } 1028 1029 /* 1030 * Creates a new instance of this GEOM class, initialise softc 1031 */ 1032 static struct g_geom * 1033 create_virstor_geom(struct g_class *mp, struct g_virstor_metadata *md) 1034 { 1035 struct g_geom *gp; 1036 struct g_virstor_softc *sc; 1037 1038 LOG_MSG(LVL_DEBUG, "Creating geom instance for %s (id=%u)", 1039 md->md_name, md->md_id); 1040 1041 if (md->md_count < 1 || md->md_chunk_size < 1 || 1042 md->md_virsize < md->md_chunk_size) { 1043 /* This is bogus configuration, and probably means data is 1044 * somehow corrupted. Panic, maybe? */ 1045 LOG_MSG(LVL_ERROR, "Nonsensical metadata information for %s", 1046 md->md_name); 1047 return (NULL); 1048 } 1049 1050 /* Check if it's already created */ 1051 LIST_FOREACH(gp, &mp->geom, geom) { 1052 sc = gp->softc; 1053 if (sc != NULL && strcmp(sc->geom->name, md->md_name) == 0) { 1054 LOG_MSG(LVL_WARNING, "Geom %s already exists", 1055 md->md_name); 1056 if (sc->id != md->md_id) { 1057 LOG_MSG(LVL_ERROR, 1058 "Some stale or invalid components " 1059 "exist for virstor device named %s. " 1060 "You will need to <CLEAR> all stale " 1061 "components and maybe reconfigure " 1062 "the virstor device. Tune " 1063 "kern.geom.virstor.debug sysctl up " 1064 "for more information.", 1065 sc->geom->name); 1066 } 1067 return (NULL); 1068 } 1069 } 1070 gp = g_new_geomf(mp, "%s", md->md_name); 1071 gp->softc = NULL; /* to circumevent races that test softc */ 1072 1073 gp->start = g_virstor_start; 1074 gp->spoiled = g_virstor_orphan; 1075 gp->orphan = g_virstor_orphan; 1076 gp->access = g_virstor_access; 1077 gp->dumpconf = g_virstor_dumpconf; 1078 1079 sc = malloc(sizeof(*sc), M_GVIRSTOR, M_WAITOK | M_ZERO); 1080 sc->id = md->md_id; 1081 sc->n_components = md->md_count; 1082 sc->components = malloc(sizeof(struct g_virstor_component) * md->md_count, 1083 M_GVIRSTOR, M_WAITOK | M_ZERO); 1084 sc->chunk_size = md->md_chunk_size; 1085 sc->virsize = md->md_virsize; 1086 STAILQ_INIT(&sc->delayed_bio_q); 1087 mtx_init(&sc->delayed_bio_q_mtx, "gvirstor_delayed_bio_q_mtx", 1088 "gvirstor", MTX_DEF | MTX_RECURSE); 1089 1090 sc->geom = gp; 1091 sc->provider = NULL; /* virstor_check_and_run will create it */ 1092 gp->softc = sc; 1093 1094 LOG_MSG(LVL_ANNOUNCE, "Device %s created", sc->geom->name); 1095 1096 return (gp); 1097 } 1098 1099 /* 1100 * Add provider to a GEOM class instance 1101 */ 1102 static int 1103 add_provider_to_geom(struct g_virstor_softc *sc, struct g_provider *pp, 1104 struct g_virstor_metadata *md) 1105 { 1106 struct g_virstor_component *component; 1107 struct g_consumer *cp, *fcp; 1108 struct g_geom *gp; 1109 int error; 1110 1111 if (md->no >= sc->n_components) 1112 return (EINVAL); 1113 1114 /* "Current" compontent */ 1115 component = &(sc->components[md->no]); 1116 if (component->gcons != NULL) 1117 return (EEXIST); 1118 1119 gp = sc->geom; 1120 fcp = LIST_FIRST(&gp->consumer); 1121 1122 cp = g_new_consumer(gp); 1123 error = g_attach(cp, pp); 1124 1125 if (error != 0) { 1126 g_destroy_consumer(cp); 1127 return (error); 1128 } 1129 1130 if (fcp != NULL) { 1131 if (fcp->provider->sectorsize != pp->sectorsize) { 1132 /* TODO: this can be made to work */ 1133 LOG_MSG(LVL_ERROR, "Provider %s of %s has invalid " 1134 "sector size (%d)", pp->name, sc->geom->name, 1135 pp->sectorsize); 1136 return (EINVAL); 1137 } 1138 if (fcp->acr > 0 || fcp->acw || fcp->ace > 0) { 1139 /* Replicate access permissions from first "live" consumer 1140 * to the new one */ 1141 error = g_access(cp, fcp->acr, fcp->acw, fcp->ace); 1142 if (error != 0) { 1143 g_detach(cp); 1144 g_destroy_consumer(cp); 1145 return (error); 1146 } 1147 } 1148 } 1149 1150 /* Bring up a new component */ 1151 cp->private = component; 1152 component->gcons = cp; 1153 component->sc = sc; 1154 component->index = md->no; 1155 component->chunk_count = md->chunk_count; 1156 component->chunk_next = md->chunk_next; 1157 component->chunk_reserved = md->chunk_reserved; 1158 component->flags = md->flags; 1159 1160 LOG_MSG(LVL_DEBUG, "%s attached to %s", pp->name, sc->geom->name); 1161 1162 virstor_check_and_run(sc); 1163 return (0); 1164 } 1165 1166 /* 1167 * Check if everything's ready to create the geom provider & device entry, 1168 * create and start provider. 1169 * Called ultimately by .taste, from g_event thread 1170 */ 1171 static void 1172 virstor_check_and_run(struct g_virstor_softc *sc) 1173 { 1174 off_t off; 1175 size_t n, count; 1176 int index; 1177 int error; 1178 1179 if (virstor_valid_components(sc) != sc->n_components) 1180 return; 1181 1182 if (virstor_valid_components(sc) == 0) { 1183 /* This is actually a candidate for panic() */ 1184 LOG_MSG(LVL_ERROR, "No valid components for %s?", 1185 sc->provider->name); 1186 return; 1187 } 1188 1189 sc->sectorsize = sc->components[0].gcons->provider->sectorsize; 1190 1191 /* Initialise allocation map from the first consumer */ 1192 sc->chunk_count = sc->virsize / sc->chunk_size; 1193 if (sc->chunk_count * (off_t)sc->chunk_size != sc->virsize) { 1194 LOG_MSG(LVL_WARNING, "Device %s truncated to %ju bytes", 1195 sc->provider->name, 1196 sc->chunk_count * (off_t)sc->chunk_size); 1197 } 1198 sc->map_size = sc->chunk_count * sizeof *(sc->map); 1199 /* The following allocation is in order of 4MB - 8MB */ 1200 sc->map = malloc(sc->map_size, M_GVIRSTOR, M_WAITOK); 1201 KASSERT(sc->map != NULL, ("%s: Memory allocation error (%zu bytes) for %s", 1202 __func__, sc->map_size, sc->provider->name)); 1203 sc->map_sectors = sc->map_size / sc->sectorsize; 1204 1205 count = 0; 1206 for (n = 0; n < sc->n_components; n++) 1207 count += sc->components[n].chunk_count; 1208 LOG_MSG(LVL_INFO, "Device %s has %zu physical chunks and %zu virtual " 1209 "(%zu KB chunks)", 1210 sc->geom->name, count, sc->chunk_count, sc->chunk_size / 1024); 1211 1212 error = g_access(sc->components[0].gcons, 1, 0, 0); 1213 if (error != 0) { 1214 LOG_MSG(LVL_ERROR, "Cannot acquire read access for %s to " 1215 "read allocation map for %s", 1216 sc->components[0].gcons->provider->name, 1217 sc->geom->name); 1218 return; 1219 } 1220 /* Read in the allocation map */ 1221 LOG_MSG(LVL_DEBUG, "Reading map for %s from %s", sc->geom->name, 1222 sc->components[0].gcons->provider->name); 1223 off = count = n = 0; 1224 while (count < sc->map_size) { 1225 struct g_virstor_map_entry *mapbuf; 1226 size_t bs; 1227 1228 bs = MIN(MAXPHYS, sc->map_size - count); 1229 if (bs % sc->sectorsize != 0) { 1230 /* Check for alignment errors */ 1231 bs = (bs / sc->sectorsize) * sc->sectorsize; 1232 if (bs == 0) 1233 break; 1234 LOG_MSG(LVL_ERROR, "Trouble: map is not sector-aligned " 1235 "for %s on %s", sc->geom->name, 1236 sc->components[0].gcons->provider->name); 1237 } 1238 mapbuf = g_read_data(sc->components[0].gcons, off, bs, &error); 1239 if (mapbuf == NULL) { 1240 free(sc->map, M_GVIRSTOR); 1241 LOG_MSG(LVL_ERROR, "Error reading allocation map " 1242 "for %s from %s (offset %ju) (error %d)", 1243 sc->geom->name, 1244 sc->components[0].gcons->provider->name, 1245 off, error); 1246 return; 1247 } 1248 1249 bcopy(mapbuf, &sc->map[n], bs); 1250 off += bs; 1251 count += bs; 1252 n += bs / sizeof *(sc->map); 1253 g_free(mapbuf); 1254 } 1255 g_access(sc->components[0].gcons, -1, 0, 0); 1256 LOG_MSG(LVL_DEBUG, "Read map for %s", sc->geom->name); 1257 1258 /* find first component with allocatable chunks */ 1259 index = -1; 1260 for (n = 0; n < sc->n_components; n++) { 1261 if (sc->components[n].chunk_next < 1262 sc->components[n].chunk_count) { 1263 index = n; 1264 break; 1265 } 1266 } 1267 if (index == -1) 1268 /* not found? set it to the last component and handle it 1269 * later */ 1270 index = sc->n_components - 1; 1271 1272 if (index >= sc->n_components - g_virstor_component_watermark - 1) { 1273 LOG_MSG(LVL_WARNING, "Device %s running out of components " 1274 "(%d/%u: %s)", sc->geom->name, 1275 index+1, 1276 sc->n_components, 1277 sc->components[index].gcons->provider->name); 1278 } 1279 sc->curr_component = index; 1280 1281 if (sc->components[index].chunk_next >= 1282 sc->components[index].chunk_count - g_virstor_chunk_watermark) { 1283 LOG_MSG(LVL_WARNING, 1284 "Component %s of %s is running out of free space " 1285 "(%u chunks left)", 1286 sc->components[index].gcons->provider->name, 1287 sc->geom->name, sc->components[index].chunk_count - 1288 sc->components[index].chunk_next); 1289 } 1290 1291 sc->me_per_sector = sc->sectorsize / sizeof *(sc->map); 1292 if (sc->sectorsize % sizeof *(sc->map) != 0) { 1293 LOG_MSG(LVL_ERROR, 1294 "%s: Map entries don't fit exactly in a sector (%s)", 1295 __func__, sc->geom->name); 1296 return; 1297 } 1298 1299 /* Recalculate allocated chunks in components & at the same time 1300 * verify map data is sane. We could trust metadata on this, but 1301 * we want to make sure. */ 1302 for (n = 0; n < sc->n_components; n++) 1303 sc->components[n].chunk_next = sc->components[n].chunk_reserved; 1304 1305 for (n = 0; n < sc->chunk_count; n++) { 1306 if (sc->map[n].provider_no >= sc->n_components || 1307 sc->map[n].provider_chunk >= 1308 sc->components[sc->map[n].provider_no].chunk_count) { 1309 LOG_MSG(LVL_ERROR, "%s: Invalid entry %u in map for %s", 1310 __func__, (u_int)n, sc->geom->name); 1311 LOG_MSG(LVL_ERROR, "%s: provider_no: %u, n_components: %u" 1312 " provider_chunk: %u, chunk_count: %u", __func__, 1313 sc->map[n].provider_no, sc->n_components, 1314 sc->map[n].provider_chunk, 1315 sc->components[sc->map[n].provider_no].chunk_count); 1316 return; 1317 } 1318 if (sc->map[n].flags & VIRSTOR_MAP_ALLOCATED) 1319 sc->components[sc->map[n].provider_no].chunk_next++; 1320 } 1321 1322 sc->provider = g_new_providerf(sc->geom, "virstor/%s", 1323 sc->geom->name); 1324 1325 sc->provider->sectorsize = sc->sectorsize; 1326 sc->provider->mediasize = sc->virsize; 1327 g_error_provider(sc->provider, 0); 1328 1329 LOG_MSG(LVL_INFO, "%s activated", sc->provider->name); 1330 LOG_MSG(LVL_DEBUG, "%s starting with current component %u, starting " 1331 "chunk %u", sc->provider->name, sc->curr_component, 1332 sc->components[sc->curr_component].chunk_next); 1333 } 1334 1335 /* 1336 * Returns count of active providers in this geom instance 1337 */ 1338 static u_int 1339 virstor_valid_components(struct g_virstor_softc *sc) 1340 { 1341 unsigned int nc, i; 1342 1343 nc = 0; 1344 KASSERT(sc != NULL, ("%s: softc is NULL", __func__)); 1345 KASSERT(sc->components != NULL, ("%s: sc->components is NULL", __func__)); 1346 for (i = 0; i < sc->n_components; i++) 1347 if (sc->components[i].gcons != NULL) 1348 nc++; 1349 return (nc); 1350 } 1351 1352 /* 1353 * Called when the consumer gets orphaned (?) 1354 */ 1355 static void 1356 g_virstor_orphan(struct g_consumer *cp) 1357 { 1358 struct g_virstor_softc *sc; 1359 struct g_virstor_component *comp; 1360 struct g_geom *gp; 1361 1362 g_topology_assert(); 1363 gp = cp->geom; 1364 sc = gp->softc; 1365 if (sc == NULL) 1366 return; 1367 1368 comp = cp->private; 1369 KASSERT(comp != NULL, ("%s: No component in private part of consumer", 1370 __func__)); 1371 remove_component(sc, comp, FALSE); 1372 if (virstor_valid_components(sc) == 0) 1373 virstor_geom_destroy(sc, TRUE, FALSE); 1374 } 1375 1376 /* 1377 * Called to notify geom when it's been opened, and for what intent 1378 */ 1379 static int 1380 g_virstor_access(struct g_provider *pp, int dr, int dw, int de) 1381 { 1382 struct g_consumer *c; 1383 struct g_virstor_softc *sc; 1384 struct g_geom *gp; 1385 int error; 1386 1387 KASSERT(pp != NULL, ("%s: NULL provider", __func__)); 1388 gp = pp->geom; 1389 KASSERT(gp != NULL, ("%s: NULL geom", __func__)); 1390 sc = gp->softc; 1391 1392 if (sc == NULL) { 1393 /* It seems that .access can be called with negative dr,dw,dx 1394 * in this case but I want to check for myself */ 1395 LOG_MSG(LVL_WARNING, "access(%d, %d, %d) for %s", 1396 dr, dw, de, pp->name); 1397 /* This should only happen when geom is withered so 1398 * allow only negative requests */ 1399 KASSERT(dr <= 0 && dw <= 0 && de <= 0, 1400 ("%s: Positive access for %s", __func__, pp->name)); 1401 if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0) 1402 LOG_MSG(LVL_DEBUG, "Device %s definitely destroyed", 1403 pp->name); 1404 return (0); 1405 } 1406 1407 /* Grab an exclusive bit to propagate on our consumers on first open */ 1408 if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0) 1409 de++; 1410 /* ... drop it on close */ 1411 if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0) { 1412 de--; 1413 update_metadata(sc); /* Writes statistical information */ 1414 } 1415 1416 error = ENXIO; 1417 LIST_FOREACH(c, &gp->consumer, consumer) { 1418 KASSERT(c != NULL, ("%s: consumer is NULL", __func__)); 1419 error = g_access(c, dr, dw, de); 1420 if (error != 0) { 1421 struct g_consumer *c2; 1422 1423 /* Backout earlier changes */ 1424 LIST_FOREACH(c2, &gp->consumer, consumer) { 1425 if (c2 == c) /* all eariler components fixed */ 1426 return (error); 1427 g_access(c2, -dr, -dw, -de); 1428 } 1429 } 1430 } 1431 1432 return (error); 1433 } 1434 1435 /* 1436 * Generate XML dump of current state 1437 */ 1438 static void 1439 g_virstor_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, 1440 struct g_consumer *cp, struct g_provider *pp) 1441 { 1442 struct g_virstor_softc *sc; 1443 1444 g_topology_assert(); 1445 sc = gp->softc; 1446 1447 if (sc == NULL || pp != NULL) 1448 return; 1449 1450 if (cp != NULL) { 1451 /* For each component */ 1452 struct g_virstor_component *comp; 1453 1454 comp = cp->private; 1455 if (comp == NULL) 1456 return; 1457 sbuf_printf(sb, "%s<ComponentIndex>%u</ComponentIndex>\n", 1458 indent, comp->index); 1459 sbuf_printf(sb, "%s<ChunkCount>%u</ChunkCount>\n", 1460 indent, comp->chunk_count); 1461 sbuf_printf(sb, "%s<ChunksUsed>%u</ChunksUsed>\n", 1462 indent, comp->chunk_next); 1463 sbuf_printf(sb, "%s<ChunksReserved>%u</ChunksReserved>\n", 1464 indent, comp->chunk_reserved); 1465 sbuf_printf(sb, "%s<StorageFree>%u%%</StorageFree>\n", 1466 indent, 1467 comp->chunk_next > 0 ? 100 - 1468 ((comp->chunk_next + comp->chunk_reserved) * 100) / 1469 comp->chunk_count : 100); 1470 } else { 1471 /* For the whole thing */ 1472 u_int count, used, i; 1473 off_t size; 1474 1475 count = used = size = 0; 1476 for (i = 0; i < sc->n_components; i++) { 1477 if (sc->components[i].gcons != NULL) { 1478 count += sc->components[i].chunk_count; 1479 used += sc->components[i].chunk_next + 1480 sc->components[i].chunk_reserved; 1481 size += sc->components[i].gcons-> 1482 provider->mediasize; 1483 } 1484 } 1485 1486 sbuf_printf(sb, "%s<Status>" 1487 "Components=%u, Online=%u</Status>\n", indent, 1488 sc->n_components, virstor_valid_components(sc)); 1489 sbuf_printf(sb, "%s<State>%u%% physical free</State>\n", 1490 indent, 100-(used * 100) / count); 1491 sbuf_printf(sb, "%s<ChunkSize>%zu</ChunkSize>\n", indent, 1492 sc->chunk_size); 1493 sbuf_printf(sb, "%s<PhysicalFree>%u%%</PhysicalFree>\n", 1494 indent, used > 0 ? 100 - (used * 100) / count : 100); 1495 sbuf_printf(sb, "%s<ChunkPhysicalCount>%u</ChunkPhysicalCount>\n", 1496 indent, count); 1497 sbuf_printf(sb, "%s<ChunkVirtualCount>%zu</ChunkVirtualCount>\n", 1498 indent, sc->chunk_count); 1499 sbuf_printf(sb, "%s<PhysicalBacking>%zu%%</PhysicalBacking>\n", 1500 indent, 1501 (count * 100) / sc->chunk_count); 1502 sbuf_printf(sb, "%s<PhysicalBackingSize>%jd</PhysicalBackingSize>\n", 1503 indent, size); 1504 sbuf_printf(sb, "%s<VirtualSize>%jd</VirtualSize>\n", indent, 1505 sc->virsize); 1506 } 1507 } 1508 1509 /* 1510 * GEOM .done handler 1511 * Can't use standard handler because one requested IO may 1512 * fork into additional data IOs 1513 */ 1514 static void 1515 g_virstor_done(struct bio *b) 1516 { 1517 struct g_virstor_softc *sc; 1518 struct bio *parent_b; 1519 1520 parent_b = b->bio_parent; 1521 sc = parent_b->bio_to->geom->softc; 1522 1523 if (b->bio_error != 0) { 1524 LOG_MSG(LVL_ERROR, "Error %d for offset=%ju, length=%ju, %s", 1525 b->bio_error, b->bio_offset, b->bio_length, 1526 b->bio_to->name); 1527 if (parent_b->bio_error == 0) 1528 parent_b->bio_error = b->bio_error; 1529 } 1530 1531 parent_b->bio_inbed++; 1532 parent_b->bio_completed += b->bio_completed; 1533 1534 if (parent_b->bio_children == parent_b->bio_inbed) { 1535 parent_b->bio_completed = parent_b->bio_length; 1536 g_io_deliver(parent_b, parent_b->bio_error); 1537 } 1538 g_destroy_bio(b); 1539 } 1540 1541 /* 1542 * I/O starts here 1543 * Called in g_down thread 1544 */ 1545 static void 1546 g_virstor_start(struct bio *b) 1547 { 1548 struct g_virstor_softc *sc; 1549 struct g_virstor_component *comp; 1550 struct bio *cb; 1551 struct g_provider *pp; 1552 char *addr; 1553 off_t offset, length; 1554 struct bio_queue_head bq; 1555 size_t chunk_size; /* cached for convenience */ 1556 u_int count; 1557 1558 pp = b->bio_to; 1559 sc = pp->geom->softc; 1560 KASSERT(sc != NULL, ("%s: no softc (error=%d, device=%s)", __func__, 1561 b->bio_to->error, b->bio_to->name)); 1562 1563 LOG_REQ(LVL_MOREDEBUG, b, "%s", __func__); 1564 1565 switch (b->bio_cmd) { 1566 case BIO_READ: 1567 case BIO_WRITE: 1568 case BIO_DELETE: 1569 break; 1570 default: 1571 g_io_deliver(b, EOPNOTSUPP); 1572 return; 1573 } 1574 1575 LOG_MSG(LVL_DEBUG2, "BIO arrived, size=%ju", b->bio_length); 1576 bioq_init(&bq); 1577 1578 chunk_size = sc->chunk_size; 1579 addr = b->bio_data; 1580 offset = b->bio_offset; /* virtual offset and length */ 1581 length = b->bio_length; 1582 1583 while (length > 0) { 1584 size_t chunk_index, in_chunk_offset, in_chunk_length; 1585 struct virstor_map_entry *me; 1586 1587 chunk_index = offset / chunk_size; /* round downwards */ 1588 in_chunk_offset = offset % chunk_size; 1589 in_chunk_length = min(length, chunk_size - in_chunk_offset); 1590 LOG_MSG(LVL_DEBUG, "Mapped %s(%ju, %ju) to (%zu,%zu,%zu)", 1591 b->bio_cmd == BIO_READ ? "R" : "W", 1592 offset, length, 1593 chunk_index, in_chunk_offset, in_chunk_length); 1594 me = &sc->map[chunk_index]; 1595 1596 if (b->bio_cmd == BIO_READ || b->bio_cmd == BIO_DELETE) { 1597 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) { 1598 /* Reads from unallocated chunks return zeroed 1599 * buffers */ 1600 if (b->bio_cmd == BIO_READ) 1601 bzero(addr, in_chunk_length); 1602 } else { 1603 comp = &sc->components[me->provider_no]; 1604 1605 cb = g_clone_bio(b); 1606 if (cb == NULL) { 1607 bioq_dismantle(&bq); 1608 if (b->bio_error == 0) 1609 b->bio_error = ENOMEM; 1610 g_io_deliver(b, b->bio_error); 1611 return; 1612 } 1613 cb->bio_to = comp->gcons->provider; 1614 cb->bio_done = g_virstor_done; 1615 cb->bio_offset = 1616 (off_t)me->provider_chunk * (off_t)chunk_size 1617 + in_chunk_offset; 1618 cb->bio_length = in_chunk_length; 1619 cb->bio_data = addr; 1620 cb->bio_caller1 = comp; 1621 bioq_disksort(&bq, cb); 1622 } 1623 } else { /* handle BIO_WRITE */ 1624 KASSERT(b->bio_cmd == BIO_WRITE, 1625 ("%s: Unknown command %d", __func__, 1626 b->bio_cmd)); 1627 1628 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) { 1629 /* We have a virtual chunk, represented by 1630 * the "me" entry, but it's not yet allocated 1631 * (tied to) a physical chunk. So do it now. */ 1632 struct virstor_map_entry *data_me; 1633 u_int phys_chunk, comp_no; 1634 off_t s_offset; 1635 int error; 1636 1637 error = allocate_chunk(sc, &comp, &comp_no, 1638 &phys_chunk); 1639 if (error != 0) { 1640 /* We cannot allocate a physical chunk 1641 * to satisfy this request, so we'll 1642 * delay it to when we can... 1643 * XXX: this will prevent the fs from 1644 * being umounted! */ 1645 struct g_virstor_bio_q *biq; 1646 biq = malloc(sizeof *biq, M_GVIRSTOR, 1647 M_NOWAIT); 1648 if (biq == NULL) { 1649 bioq_dismantle(&bq); 1650 if (b->bio_error == 0) 1651 b->bio_error = ENOMEM; 1652 g_io_deliver(b, b->bio_error); 1653 return; 1654 } 1655 biq->bio = b; 1656 mtx_lock(&sc->delayed_bio_q_mtx); 1657 STAILQ_INSERT_TAIL(&sc->delayed_bio_q, 1658 biq, linkage); 1659 mtx_unlock(&sc->delayed_bio_q_mtx); 1660 LOG_MSG(LVL_WARNING, "Delaying BIO " 1661 "(size=%ju) until free physical " 1662 "space can be found on %s", 1663 b->bio_length, 1664 sc->provider->name); 1665 return; 1666 } 1667 LOG_MSG(LVL_DEBUG, "Allocated chunk %u on %s " 1668 "for %s", 1669 phys_chunk, 1670 comp->gcons->provider->name, 1671 sc->provider->name); 1672 1673 me->provider_no = comp_no; 1674 me->provider_chunk = phys_chunk; 1675 me->flags |= VIRSTOR_MAP_ALLOCATED; 1676 1677 cb = g_clone_bio(b); 1678 if (cb == NULL) { 1679 me->flags &= ~VIRSTOR_MAP_ALLOCATED; 1680 me->provider_no = 0; 1681 me->provider_chunk = 0; 1682 bioq_dismantle(&bq); 1683 if (b->bio_error == 0) 1684 b->bio_error = ENOMEM; 1685 g_io_deliver(b, b->bio_error); 1686 return; 1687 } 1688 1689 /* The allocation table is stored continuously 1690 * at the start of the drive. We need to 1691 * calculate the offset of the sector that holds 1692 * this map entry both on the drive and in the 1693 * map array. 1694 * sc_offset will end up pointing to the drive 1695 * sector. */ 1696 s_offset = chunk_index * sizeof *me; 1697 s_offset = (s_offset / sc->sectorsize) * 1698 sc->sectorsize; 1699 1700 /* data_me points to map entry sector 1701 * in memory (analoguos to offset) */ 1702 data_me = &sc->map[(chunk_index / 1703 sc->me_per_sector) * sc->me_per_sector]; 1704 1705 /* Commit sector with map entry to storage */ 1706 cb->bio_to = sc->components[0].gcons->provider; 1707 cb->bio_done = g_virstor_done; 1708 cb->bio_offset = s_offset; 1709 cb->bio_data = (char *)data_me; 1710 cb->bio_length = sc->sectorsize; 1711 cb->bio_caller1 = &sc->components[0]; 1712 bioq_disksort(&bq, cb); 1713 } 1714 1715 comp = &sc->components[me->provider_no]; 1716 cb = g_clone_bio(b); 1717 if (cb == NULL) { 1718 bioq_dismantle(&bq); 1719 if (b->bio_error == 0) 1720 b->bio_error = ENOMEM; 1721 g_io_deliver(b, b->bio_error); 1722 return; 1723 } 1724 /* Finally, handle the data */ 1725 cb->bio_to = comp->gcons->provider; 1726 cb->bio_done = g_virstor_done; 1727 cb->bio_offset = (off_t)me->provider_chunk*(off_t)chunk_size + 1728 in_chunk_offset; 1729 cb->bio_length = in_chunk_length; 1730 cb->bio_data = addr; 1731 cb->bio_caller1 = comp; 1732 bioq_disksort(&bq, cb); 1733 } 1734 addr += in_chunk_length; 1735 length -= in_chunk_length; 1736 offset += in_chunk_length; 1737 } 1738 1739 /* Fire off bio's here */ 1740 count = 0; 1741 for (cb = bioq_first(&bq); cb != NULL; cb = bioq_first(&bq)) { 1742 bioq_remove(&bq, cb); 1743 LOG_REQ(LVL_MOREDEBUG, cb, "Firing request"); 1744 comp = cb->bio_caller1; 1745 cb->bio_caller1 = NULL; 1746 LOG_MSG(LVL_DEBUG, " firing bio, offset=%ju, length=%ju", 1747 cb->bio_offset, cb->bio_length); 1748 g_io_request(cb, comp->gcons); 1749 count++; 1750 } 1751 if (count == 0) { /* We handled everything locally */ 1752 b->bio_completed = b->bio_length; 1753 g_io_deliver(b, 0); 1754 } 1755 1756 } 1757 1758 /* 1759 * Allocate a chunk from a physical provider. Returns physical component, 1760 * chunk index relative to the component and the component's index. 1761 */ 1762 static int 1763 allocate_chunk(struct g_virstor_softc *sc, struct g_virstor_component **comp, 1764 u_int *comp_no_p, u_int *chunk) 1765 { 1766 u_int comp_no; 1767 1768 KASSERT(sc->curr_component < sc->n_components, 1769 ("%s: Invalid curr_component: %u", __func__, sc->curr_component)); 1770 1771 comp_no = sc->curr_component; 1772 *comp = &sc->components[comp_no]; 1773 dump_component(*comp); 1774 if ((*comp)->chunk_next >= (*comp)->chunk_count) { 1775 /* This component is full. Allocate next component */ 1776 if (comp_no >= sc->n_components-1) { 1777 LOG_MSG(LVL_ERROR, "All physical space allocated for %s", 1778 sc->geom->name); 1779 return (-1); 1780 } 1781 (*comp)->flags &= ~VIRSTOR_PROVIDER_CURRENT; 1782 sc->curr_component = ++comp_no; 1783 1784 *comp = &sc->components[comp_no]; 1785 if (comp_no >= sc->n_components - g_virstor_component_watermark-1) 1786 LOG_MSG(LVL_WARNING, "Device %s running out of components " 1787 "(switching to %u/%u: %s)", sc->geom->name, 1788 comp_no+1, sc->n_components, 1789 (*comp)->gcons->provider->name); 1790 /* Take care not to overwrite reserved chunks */ 1791 if ( (*comp)->chunk_reserved > 0 && 1792 (*comp)->chunk_next < (*comp)->chunk_reserved) 1793 (*comp)->chunk_next = (*comp)->chunk_reserved; 1794 1795 (*comp)->flags |= 1796 VIRSTOR_PROVIDER_ALLOCATED | VIRSTOR_PROVIDER_CURRENT; 1797 dump_component(*comp); 1798 *comp_no_p = comp_no; 1799 *chunk = (*comp)->chunk_next++; 1800 } else { 1801 *comp_no_p = comp_no; 1802 *chunk = (*comp)->chunk_next++; 1803 } 1804 return (0); 1805 } 1806 1807 /* Dump a component */ 1808 static void 1809 dump_component(struct g_virstor_component *comp) 1810 { 1811 1812 if (g_virstor_debug < LVL_DEBUG2) 1813 return; 1814 printf("Component %d: %s\n", comp->index, comp->gcons->provider->name); 1815 printf(" chunk_count: %u\n", comp->chunk_count); 1816 printf(" chunk_next: %u\n", comp->chunk_next); 1817 printf(" flags: %u\n", comp->flags); 1818 } 1819 1820 #if 0 1821 /* Dump a map entry */ 1822 static void 1823 dump_me(struct virstor_map_entry *me, unsigned int nr) 1824 { 1825 if (g_virstor_debug < LVL_DEBUG) 1826 return; 1827 printf("VIRT. CHUNK #%d: ", nr); 1828 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) 1829 printf("(unallocated)\n"); 1830 else 1831 printf("allocated at provider %u, provider_chunk %u\n", 1832 me->provider_no, me->provider_chunk); 1833 } 1834 #endif 1835 1836 /* 1837 * Dismantle bio_queue and destroy its components 1838 */ 1839 static void 1840 bioq_dismantle(struct bio_queue_head *bq) 1841 { 1842 struct bio *b; 1843 1844 for (b = bioq_first(bq); b != NULL; b = bioq_first(bq)) { 1845 bioq_remove(bq, b); 1846 g_destroy_bio(b); 1847 } 1848 } 1849 1850 /* 1851 * The function that shouldn't be called. 1852 * When this is called, the stack is already garbled because of 1853 * argument mismatch. There's nothing to do now but panic, which is 1854 * accidentally the whole purpose of this function. 1855 * Motivation: to guard from accidentally calling geom methods when 1856 * they shouldn't be called. (see g_..._taste) 1857 */ 1858 static void 1859 invalid_call(void) 1860 { 1861 panic("invalid_call() has just been called. Something's fishy here."); 1862 } 1863 1864 DECLARE_GEOM_CLASS(g_virstor_class, g_virstor); /* Let there be light */
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