g_virstor.c revision 223921
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: head/sys/geom/virstor/g_virstor.c 223921 2011-07-11 05:22:31Z ae $"); 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/sbuf.h> 44#include <sys/sysctl.h> 45#include <sys/malloc.h> 46#include <sys/time.h> 47#include <sys/proc.h> 48#include <sys/kthread.h> 49#include <sys/mutex.h> 50#include <vm/uma.h> 51#include <geom/geom.h> 52 53#include <geom/virstor/g_virstor.h> 54#include <geom/virstor/g_virstor_md.h> 55 56FEATURE(g_virstor, "GEOM virtual storage support"); 57 58/* Declare malloc(9) label */ 59static MALLOC_DEFINE(M_GVIRSTOR, "gvirstor", "GEOM_VIRSTOR Data"); 60 61/* GEOM class methods */ 62static g_init_t g_virstor_init; 63static g_fini_t g_virstor_fini; 64static g_taste_t g_virstor_taste; 65static g_ctl_req_t g_virstor_config; 66static g_ctl_destroy_geom_t g_virstor_destroy_geom; 67 68/* Declare & initialize class structure ("geom class") */ 69struct g_class g_virstor_class = { 70 .name = G_VIRSTOR_CLASS_NAME, 71 .version = G_VERSION, 72 .init = g_virstor_init, 73 .fini = g_virstor_fini, 74 .taste = g_virstor_taste, 75 .ctlreq = g_virstor_config, 76 .destroy_geom = g_virstor_destroy_geom 77 /* The .dumpconf and the rest are only usable for a geom instance, so 78 * they will be set when such instance is created. */ 79}; 80 81/* Declare sysctl's and loader tunables */ 82SYSCTL_DECL(_kern_geom); 83SYSCTL_NODE(_kern_geom, OID_AUTO, virstor, CTLFLAG_RW, 0, "GEOM_GVIRSTOR information"); 84 85static u_int g_virstor_debug = 2; /* XXX: lower to 2 when released to public */ 86TUNABLE_INT("kern.geom.virstor.debug", &g_virstor_debug); 87SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, debug, CTLFLAG_RW, &g_virstor_debug, 88 0, "Debug level (2=production, 5=normal, 15=excessive)"); 89 90static u_int g_virstor_chunk_watermark = 100; 91TUNABLE_INT("kern.geom.virstor.chunk_watermark", &g_virstor_chunk_watermark); 92SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, chunk_watermark, CTLFLAG_RW, 93 &g_virstor_chunk_watermark, 0, 94 "Minimum number of free chunks before issuing administrative warning"); 95 96static u_int g_virstor_component_watermark = 1; 97TUNABLE_INT("kern.geom.virstor.component_watermark", 98 &g_virstor_component_watermark); 99SYSCTL_UINT(_kern_geom_virstor, OID_AUTO, component_watermark, CTLFLAG_RW, 100 &g_virstor_component_watermark, 0, 101 "Minimum number of free components before issuing administrative warning"); 102 103static int read_metadata(struct g_consumer *, struct g_virstor_metadata *); 104static void write_metadata(struct g_consumer *, struct g_virstor_metadata *); 105static int clear_metadata(struct g_virstor_component *); 106static int add_provider_to_geom(struct g_virstor_softc *, struct g_provider *, 107 struct g_virstor_metadata *); 108static struct g_geom *create_virstor_geom(struct g_class *, 109 struct g_virstor_metadata *); 110static void virstor_check_and_run(struct g_virstor_softc *); 111static u_int virstor_valid_components(struct g_virstor_softc *); 112static int virstor_geom_destroy(struct g_virstor_softc *, boolean_t, 113 boolean_t); 114static void remove_component(struct g_virstor_softc *, 115 struct g_virstor_component *, boolean_t); 116static void bioq_dismantle(struct bio_queue_head *); 117static int allocate_chunk(struct g_virstor_softc *, 118 struct g_virstor_component **, u_int *, u_int *); 119static void delay_destroy_consumer(void *, int); 120static void dump_component(struct g_virstor_component *comp); 121#if 0 122static void dump_me(struct virstor_map_entry *me, unsigned int nr); 123#endif 124 125static void virstor_ctl_stop(struct gctl_req *, struct g_class *); 126static void virstor_ctl_add(struct gctl_req *, struct g_class *); 127static void virstor_ctl_remove(struct gctl_req *, struct g_class *); 128static struct g_virstor_softc * virstor_find_geom(const struct g_class *, 129 const char *); 130static void update_metadata(struct g_virstor_softc *); 131static void fill_metadata(struct g_virstor_softc *, struct g_virstor_metadata *, 132 u_int, u_int); 133 134static void g_virstor_orphan(struct g_consumer *); 135static int g_virstor_access(struct g_provider *, int, int, int); 136static void g_virstor_start(struct bio *); 137static void g_virstor_dumpconf(struct sbuf *, const char *, struct g_geom *, 138 struct g_consumer *, struct g_provider *); 139static void g_virstor_done(struct bio *); 140 141static void invalid_call(void); 142/* 143 * Initialise GEOM class (per-class callback) 144 */ 145static void 146g_virstor_init(struct g_class *mp __unused) 147{ 148 149 /* Catch map struct size mismatch at compile time; Map entries must 150 * fit into MAXPHYS exactly, with no wasted space. */ 151 CTASSERT(VIRSTOR_MAP_BLOCK_ENTRIES*VIRSTOR_MAP_ENTRY_SIZE == MAXPHYS); 152 153 /* Init UMA zones, TAILQ's, other global vars */ 154} 155 156/* 157 * Finalise GEOM class (per-class callback) 158 */ 159static void 160g_virstor_fini(struct g_class *mp __unused) 161{ 162 163 /* Deinit UMA zones & global vars */ 164} 165 166/* 167 * Config (per-class callback) 168 */ 169static void 170g_virstor_config(struct gctl_req *req, struct g_class *cp, char const *verb) 171{ 172 uint32_t *version; 173 174 g_topology_assert(); 175 176 version = gctl_get_paraml(req, "version", sizeof(*version)); 177 if (version == NULL) { 178 gctl_error(req, "Failed to get 'version' argument"); 179 return; 180 } 181 if (*version != G_VIRSTOR_VERSION) { 182 gctl_error(req, "Userland and kernel versions out of sync"); 183 return; 184 } 185 186 g_topology_unlock(); 187 if (strcmp(verb, "add") == 0) 188 virstor_ctl_add(req, cp); 189 else if (strcmp(verb, "stop") == 0 || strcmp(verb, "destroy") == 0) 190 virstor_ctl_stop(req, cp); 191 else if (strcmp(verb, "remove") == 0) 192 virstor_ctl_remove(req, cp); 193 else 194 gctl_error(req, "unknown verb: '%s'", verb); 195 g_topology_lock(); 196} 197 198/* 199 * "stop" verb from userland 200 */ 201static void 202virstor_ctl_stop(struct gctl_req *req, struct g_class *cp) 203{ 204 int *force, *nargs; 205 int i; 206 207 nargs = gctl_get_paraml(req, "nargs", sizeof *nargs); 208 if (nargs == NULL) { 209 gctl_error(req, "Error fetching argument '%s'", "nargs"); 210 return; 211 } 212 if (*nargs < 1) { 213 gctl_error(req, "Invalid number of arguments"); 214 return; 215 } 216 force = gctl_get_paraml(req, "force", sizeof *force); 217 if (force == NULL) { 218 gctl_error(req, "Error fetching argument '%s'", "force"); 219 return; 220 } 221 222 g_topology_lock(); 223 for (i = 0; i < *nargs; i++) { 224 char param[8]; 225 const char *name; 226 struct g_virstor_softc *sc; 227 int error; 228 229 sprintf(param, "arg%d", i); 230 name = gctl_get_asciiparam(req, param); 231 if (name == NULL) { 232 gctl_error(req, "No 'arg%d' argument", i); 233 g_topology_unlock(); 234 return; 235 } 236 sc = virstor_find_geom(cp, name); 237 LOG_MSG(LVL_INFO, "Stopping %s by the userland command", 238 sc->geom->name); 239 update_metadata(sc); 240 if ((error = virstor_geom_destroy(sc, TRUE, TRUE)) != 0) { 241 LOG_MSG(LVL_ERROR, "Cannot destroy %s: %d", 242 sc->geom->name, error); 243 } 244 } 245 g_topology_unlock(); 246} 247 248/* 249 * "add" verb from userland - add new component(s) to the structure. 250 * This will be done all at once in here, without going through the 251 * .taste function for new components. 252 */ 253static void 254virstor_ctl_add(struct gctl_req *req, struct g_class *cp) 255{ 256 /* Note: while this is going on, I/O is being done on 257 * the g_up and g_down threads. The idea is to make changes 258 * to softc members in a way that can atomically activate 259 * them all at once. */ 260 struct g_virstor_softc *sc; 261 int *hardcode, *nargs; 262 const char *geom_name; /* geom to add a component to */ 263 struct g_consumer *fcp; 264 struct g_virstor_bio_q *bq; 265 u_int added; 266 int error; 267 int i; 268 269 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs)); 270 if (nargs == NULL) { 271 gctl_error(req, "Error fetching argument '%s'", "nargs"); 272 return; 273 } 274 if (*nargs < 2) { 275 gctl_error(req, "Invalid number of arguments"); 276 return; 277 } 278 hardcode = gctl_get_paraml(req, "hardcode", sizeof(*hardcode)); 279 if (hardcode == NULL) { 280 gctl_error(req, "Error fetching argument '%s'", "hardcode"); 281 return; 282 } 283 284 /* Find "our" geom */ 285 geom_name = gctl_get_asciiparam(req, "arg0"); 286 if (geom_name == NULL) { 287 gctl_error(req, "Error fetching argument '%s'", "geom_name (arg0)"); 288 return; 289 } 290 sc = virstor_find_geom(cp, geom_name); 291 if (sc == NULL) { 292 gctl_error(req, "Don't know anything about '%s'", geom_name); 293 return; 294 } 295 296 if (virstor_valid_components(sc) != sc->n_components) { 297 LOG_MSG(LVL_ERROR, "Cannot add components to incomplete " 298 "virstor %s", sc->geom->name); 299 gctl_error(req, "Virstor %s is incomplete", sc->geom->name); 300 return; 301 } 302 303 fcp = sc->components[0].gcons; 304 added = 0; 305 g_topology_lock(); 306 for (i = 1; i < *nargs; i++) { 307 struct g_virstor_metadata md; 308 char aname[8]; 309 const char *prov_name; 310 struct g_provider *pp; 311 struct g_consumer *cp; 312 u_int nc; 313 u_int j; 314 315 snprintf(aname, sizeof aname, "arg%d", i); 316 prov_name = gctl_get_asciiparam(req, aname); 317 if (prov_name == NULL) { 318 gctl_error(req, "Error fetching argument '%s'", aname); 319 g_topology_unlock(); 320 return; 321 } 322 if (strncmp(prov_name, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0) 323 prov_name += sizeof(_PATH_DEV) - 1; 324 325 pp = g_provider_by_name(prov_name); 326 if (pp == NULL) { 327 /* This is the most common error so be verbose about it */ 328 if (added != 0) { 329 gctl_error(req, "Invalid provider: '%s' (added" 330 " %u components)", prov_name, added); 331 update_metadata(sc); 332 } else { 333 gctl_error(req, "Invalid provider: '%s'", 334 prov_name); 335 } 336 g_topology_unlock(); 337 return; 338 } 339 cp = g_new_consumer(sc->geom); 340 if (cp == NULL) { 341 gctl_error(req, "Cannot create consumer"); 342 g_topology_unlock(); 343 return; 344 } 345 error = g_attach(cp, pp); 346 if (error != 0) { 347 gctl_error(req, "Cannot attach a consumer to %s", 348 pp->name); 349 g_destroy_consumer(cp); 350 g_topology_unlock(); 351 return; 352 } 353 if (fcp->acr != 0 || fcp->acw != 0 || fcp->ace != 0) { 354 error = g_access(cp, fcp->acr, fcp->acw, fcp->ace); 355 if (error != 0) { 356 gctl_error(req, "Access request failed for %s", 357 pp->name); 358 g_destroy_consumer(cp); 359 g_topology_unlock(); 360 return; 361 } 362 } 363 if (fcp->provider->sectorsize != pp->sectorsize) { 364 gctl_error(req, "Sector size doesn't fit for %s", 365 pp->name); 366 g_destroy_consumer(cp); 367 g_topology_unlock(); 368 return; 369 } 370 for (j = 0; j < sc->n_components; j++) { 371 if (strcmp(sc->components[j].gcons->provider->name, 372 pp->name) == 0) { 373 gctl_error(req, "Component %s already in %s", 374 pp->name, sc->geom->name); 375 g_destroy_consumer(cp); 376 g_topology_unlock(); 377 return; 378 } 379 } 380 sc->components = realloc(sc->components, 381 sizeof(*sc->components) * (sc->n_components + 1), 382 M_GVIRSTOR, M_WAITOK); 383 384 nc = sc->n_components; 385 sc->components[nc].gcons = cp; 386 sc->components[nc].sc = sc; 387 sc->components[nc].index = nc; 388 sc->components[nc].chunk_count = cp->provider->mediasize / 389 sc->chunk_size; 390 sc->components[nc].chunk_next = 0; 391 sc->components[nc].chunk_reserved = 0; 392 393 if (sc->components[nc].chunk_count < 4) { 394 gctl_error(req, "Provider too small: %s", 395 cp->provider->name); 396 g_destroy_consumer(cp); 397 g_topology_unlock(); 398 return; 399 } 400 fill_metadata(sc, &md, nc, *hardcode); 401 write_metadata(cp, &md); 402 /* The new component becomes visible when n_components is 403 * incremented */ 404 sc->n_components++; 405 added++; 406 407 } 408 /* This call to update_metadata() is critical. In case there's a 409 * power failure in the middle of it and some components are updated 410 * while others are not, there will be trouble on next .taste() iff 411 * a non-updated component is detected first */ 412 update_metadata(sc); 413 g_topology_unlock(); 414 LOG_MSG(LVL_INFO, "Added %d component(s) to %s", added, 415 sc->geom->name); 416 /* Fire off BIOs previously queued because there wasn't any 417 * physical space left. If the BIOs still can't be satisfied 418 * they will again be added to the end of the queue (during 419 * which the mutex will be recursed) */ 420 bq = malloc(sizeof(*bq), M_GVIRSTOR, M_WAITOK); 421 bq->bio = NULL; 422 mtx_lock(&sc->delayed_bio_q_mtx); 423 /* First, insert a sentinel to the queue end, so we don't 424 * end up in an infinite loop if there's still no free 425 * space available. */ 426 STAILQ_INSERT_TAIL(&sc->delayed_bio_q, bq, linkage); 427 while (!STAILQ_EMPTY(&sc->delayed_bio_q)) { 428 bq = STAILQ_FIRST(&sc->delayed_bio_q); 429 if (bq->bio != NULL) { 430 g_virstor_start(bq->bio); 431 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage); 432 free(bq, M_GVIRSTOR); 433 } else { 434 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage); 435 free(bq, M_GVIRSTOR); 436 break; 437 } 438 } 439 mtx_unlock(&sc->delayed_bio_q_mtx); 440 441} 442 443/* 444 * Find a geom handled by the class 445 */ 446static struct g_virstor_softc * 447virstor_find_geom(const struct g_class *cp, const char *name) 448{ 449 struct g_geom *gp; 450 451 LIST_FOREACH(gp, &cp->geom, geom) { 452 if (strcmp(name, gp->name) == 0) 453 return (gp->softc); 454 } 455 return (NULL); 456} 457 458/* 459 * Update metadata on all components to reflect the current state 460 * of these fields: 461 * - chunk_next 462 * - flags 463 * - md_count 464 * Expects things to be set up so write_metadata() can work, i.e. 465 * the topology lock must be held. 466 */ 467static void 468update_metadata(struct g_virstor_softc *sc) 469{ 470 struct g_virstor_metadata md; 471 int n; 472 473 if (virstor_valid_components(sc) != sc->n_components) 474 return; /* Incomplete device */ 475 LOG_MSG(LVL_DEBUG, "Updating metadata on components for %s", 476 sc->geom->name); 477 /* Update metadata on components */ 478 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, 479 sc->geom->class->name, sc->geom->name); 480 g_topology_assert(); 481 for (n = 0; n < sc->n_components; n++) { 482 read_metadata(sc->components[n].gcons, &md); 483 md.chunk_next = sc->components[n].chunk_next; 484 md.flags = sc->components[n].flags; 485 md.md_count = sc->n_components; 486 write_metadata(sc->components[n].gcons, &md); 487 } 488} 489 490/* 491 * Fills metadata (struct md) from information stored in softc and the nc'th 492 * component of virstor 493 */ 494static void 495fill_metadata(struct g_virstor_softc *sc, struct g_virstor_metadata *md, 496 u_int nc, u_int hardcode) 497{ 498 struct g_virstor_component *c; 499 500 bzero(md, sizeof *md); 501 c = &sc->components[nc]; 502 503 strncpy(md->md_magic, G_VIRSTOR_MAGIC, sizeof md->md_magic); 504 md->md_version = G_VIRSTOR_VERSION; 505 strncpy(md->md_name, sc->geom->name, sizeof md->md_name); 506 md->md_id = sc->id; 507 md->md_virsize = sc->virsize; 508 md->md_chunk_size = sc->chunk_size; 509 md->md_count = sc->n_components; 510 511 if (hardcode) { 512 strncpy(md->provider, c->gcons->provider->name, 513 sizeof md->provider); 514 } 515 md->no = nc; 516 md->provsize = c->gcons->provider->mediasize; 517 md->chunk_count = c->chunk_count; 518 md->chunk_next = c->chunk_next; 519 md->chunk_reserved = c->chunk_reserved; 520 md->flags = c->flags; 521} 522 523/* 524 * Remove a component from virstor device. 525 * Can only be done if the component is unallocated. 526 */ 527static void 528virstor_ctl_remove(struct gctl_req *req, struct g_class *cp) 529{ 530 /* As this is executed in parallel to I/O, operations on virstor 531 * structures must be as atomic as possible. */ 532 struct g_virstor_softc *sc; 533 int *nargs; 534 const char *geom_name; 535 u_int removed; 536 int i; 537 538 nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs)); 539 if (nargs == NULL) { 540 gctl_error(req, "Error fetching argument '%s'", "nargs"); 541 return; 542 } 543 if (*nargs < 2) { 544 gctl_error(req, "Invalid number of arguments"); 545 return; 546 } 547 /* Find "our" geom */ 548 geom_name = gctl_get_asciiparam(req, "arg0"); 549 if (geom_name == NULL) { 550 gctl_error(req, "Error fetching argument '%s'", 551 "geom_name (arg0)"); 552 return; 553 } 554 sc = virstor_find_geom(cp, geom_name); 555 if (sc == NULL) { 556 gctl_error(req, "Don't know anything about '%s'", geom_name); 557 return; 558 } 559 560 if (virstor_valid_components(sc) != sc->n_components) { 561 LOG_MSG(LVL_ERROR, "Cannot remove components from incomplete " 562 "virstor %s", sc->geom->name); 563 gctl_error(req, "Virstor %s is incomplete", sc->geom->name); 564 return; 565 } 566 567 removed = 0; 568 for (i = 1; i < *nargs; i++) { 569 char param[8]; 570 const char *prov_name; 571 int j, found; 572 struct g_virstor_component *newcomp, *compbak; 573 574 sprintf(param, "arg%d", i); 575 prov_name = gctl_get_asciiparam(req, param); 576 if (prov_name == NULL) { 577 gctl_error(req, "Error fetching argument '%s'", param); 578 return; 579 } 580 if (strncmp(prov_name, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0) 581 prov_name += sizeof(_PATH_DEV) - 1; 582 583 found = -1; 584 for (j = 0; j < sc->n_components; j++) { 585 if (strcmp(sc->components[j].gcons->provider->name, 586 prov_name) == 0) { 587 found = j; 588 break; 589 } 590 } 591 if (found == -1) { 592 LOG_MSG(LVL_ERROR, "No %s component in %s", 593 prov_name, sc->geom->name); 594 continue; 595 } 596 597 compbak = sc->components; 598 newcomp = malloc(sc->n_components * sizeof(*sc->components), 599 M_GVIRSTOR, M_WAITOK | M_ZERO); 600 bcopy(sc->components, newcomp, found * sizeof(*sc->components)); 601 bcopy(&sc->components[found + 1], newcomp + found, 602 found * sizeof(*sc->components)); 603 if ((sc->components[j].flags & VIRSTOR_PROVIDER_ALLOCATED) != 0) { 604 LOG_MSG(LVL_ERROR, "Allocated provider %s cannot be " 605 "removed from %s", 606 prov_name, sc->geom->name); 607 free(newcomp, M_GVIRSTOR); 608 /* We'll consider this non-fatal error */ 609 continue; 610 } 611 /* Renumerate unallocated components */ 612 for (j = 0; j < sc->n_components-1; j++) { 613 if ((sc->components[j].flags & 614 VIRSTOR_PROVIDER_ALLOCATED) == 0) { 615 sc->components[j].index = j; 616 } 617 } 618 /* This is the critical section. If a component allocation 619 * event happens while both variables are not yet set, 620 * there will be trouble. Something will panic on encountering 621 * NULL sc->components[x].gcomp member. 622 * Luckily, component allocation happens very rarely and 623 * removing components is an abnormal action in any case. */ 624 sc->components = newcomp; 625 sc->n_components--; 626 /* End critical section */ 627 628 g_topology_lock(); 629 if (clear_metadata(&compbak[found]) != 0) { 630 LOG_MSG(LVL_WARNING, "Trouble ahead: cannot clear " 631 "metadata on %s", prov_name); 632 } 633 g_detach(compbak[found].gcons); 634 g_destroy_consumer(compbak[found].gcons); 635 g_topology_unlock(); 636 637 free(compbak, M_GVIRSTOR); 638 639 removed++; 640 } 641 642 /* This call to update_metadata() is critical. In case there's a 643 * power failure in the middle of it and some components are updated 644 * while others are not, there will be trouble on next .taste() iff 645 * a non-updated component is detected first */ 646 g_topology_lock(); 647 update_metadata(sc); 648 g_topology_unlock(); 649 LOG_MSG(LVL_INFO, "Removed %d component(s) from %s", removed, 650 sc->geom->name); 651} 652 653/* 654 * Clear metadata sector on component 655 */ 656static int 657clear_metadata(struct g_virstor_component *comp) 658{ 659 char *buf; 660 int error; 661 662 LOG_MSG(LVL_INFO, "Clearing metadata on %s", 663 comp->gcons->provider->name); 664 g_topology_assert(); 665 error = g_access(comp->gcons, 0, 1, 0); 666 if (error != 0) 667 return (error); 668 buf = malloc(comp->gcons->provider->sectorsize, M_GVIRSTOR, 669 M_WAITOK | M_ZERO); 670 error = g_write_data(comp->gcons, 671 comp->gcons->provider->mediasize - 672 comp->gcons->provider->sectorsize, 673 buf, 674 comp->gcons->provider->sectorsize); 675 free(buf, M_GVIRSTOR); 676 g_access(comp->gcons, 0, -1, 0); 677 return (error); 678} 679 680/* 681 * Destroy geom forcibly. 682 */ 683static int 684g_virstor_destroy_geom(struct gctl_req *req __unused, struct g_class *mp, 685 struct g_geom *gp) 686{ 687 struct g_virstor_softc *sc; 688 int exitval; 689 690 sc = gp->softc; 691 KASSERT(sc != NULL, ("%s: NULL sc", __func__)); 692 693 exitval = 0; 694 LOG_MSG(LVL_DEBUG, "%s called for %s, sc=%p", __func__, gp->name, 695 gp->softc); 696 697 if (sc != NULL) { 698#ifdef INVARIANTS 699 char *buf; 700 int error; 701 off_t off; 702 int isclean, count; 703 int n; 704 705 LOG_MSG(LVL_INFO, "INVARIANTS detected"); 706 LOG_MSG(LVL_INFO, "Verifying allocation " 707 "table for %s", sc->geom->name); 708 count = 0; 709 for (n = 0; n < sc->chunk_count; n++) { 710 if (sc->map[n].flags || VIRSTOR_MAP_ALLOCATED != 0) 711 count++; 712 } 713 LOG_MSG(LVL_INFO, "Device %s has %d allocated chunks", 714 sc->geom->name, count); 715 n = off = count = 0; 716 isclean = 1; 717 if (virstor_valid_components(sc) != sc->n_components) { 718 /* This is a incomplete virstor device (not all 719 * components have been found) */ 720 LOG_MSG(LVL_ERROR, "Device %s is incomplete", 721 sc->geom->name); 722 goto bailout; 723 } 724 error = g_access(sc->components[0].gcons, 1, 0, 0); 725 KASSERT(error == 0, ("%s: g_access failed (%d)", __func__, 726 error)); 727 /* Compare the whole on-disk allocation table with what's 728 * currently in memory */ 729 while (n < sc->chunk_count) { 730 buf = g_read_data(sc->components[0].gcons, off, 731 sc->sectorsize, &error); 732 KASSERT(buf != NULL, ("g_read_data returned NULL (%d) " 733 "for read at %jd", error, off)); 734 if (bcmp(buf, &sc->map[n], sc->sectorsize) != 0) { 735 LOG_MSG(LVL_ERROR, "ERROR in allocation table, " 736 "entry %d, offset %jd", n, off); 737 isclean = 0; 738 count++; 739 } 740 n += sc->me_per_sector; 741 off += sc->sectorsize; 742 g_free(buf); 743 } 744 error = g_access(sc->components[0].gcons, -1, 0, 0); 745 KASSERT(error == 0, ("%s: g_access failed (%d) on exit", 746 __func__, error)); 747 if (isclean != 1) { 748 LOG_MSG(LVL_ERROR, "ALLOCATION TABLE CORRUPTED FOR %s " 749 "(%d sectors don't match, max %zu allocations)", 750 sc->geom->name, count, 751 count * sc->me_per_sector); 752 } else { 753 LOG_MSG(LVL_INFO, "Allocation table ok for %s", 754 sc->geom->name); 755 } 756bailout: 757#endif 758 update_metadata(sc); 759 virstor_geom_destroy(sc, FALSE, FALSE); 760 exitval = EAGAIN; 761 } else 762 exitval = 0; 763 return (exitval); 764} 765 766/* 767 * Taste event (per-class callback) 768 * Examines a provider and creates geom instances if needed 769 */ 770static struct g_geom * 771g_virstor_taste(struct g_class *mp, struct g_provider *pp, int flags) 772{ 773 struct g_virstor_metadata md; 774 struct g_geom *gp; 775 struct g_consumer *cp; 776 struct g_virstor_softc *sc; 777 int error; 778 779 g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name); 780 g_topology_assert(); 781 LOG_MSG(LVL_DEBUG, "Tasting %s", pp->name); 782 783 /* We need a dummy geom to attach a consumer to the given provider */ 784 gp = g_new_geomf(mp, "virstor:taste.helper"); 785 gp->start = (void *)invalid_call; /* XXX: hacked up so the */ 786 gp->access = (void *)invalid_call; /* compiler doesn't complain. */ 787 gp->orphan = (void *)invalid_call; /* I really want these to fail. */ 788 789 cp = g_new_consumer(gp); 790 g_attach(cp, pp); 791 error = read_metadata(cp, &md); 792 g_detach(cp); 793 g_destroy_consumer(cp); 794 g_destroy_geom(gp); 795 796 if (error != 0) 797 return (NULL); 798 799 if (strcmp(md.md_magic, G_VIRSTOR_MAGIC) != 0) 800 return (NULL); 801 if (md.md_version != G_VIRSTOR_VERSION) { 802 LOG_MSG(LVL_ERROR, "Kernel module version invalid " 803 "to handle %s (%s) : %d should be %d", 804 md.md_name, pp->name, md.md_version, G_VIRSTOR_VERSION); 805 return (NULL); 806 } 807 if (md.provsize != pp->mediasize) 808 return (NULL); 809 810 /* If the provider name is hardcoded, use the offered provider only 811 * if it's been offered with its proper name (the one used in 812 * the label command). */ 813 if (md.provider[0] != '\0' && 814 !g_compare_names(md.provider, pp->name)) 815 return (NULL); 816 817 /* Iterate all geoms this class already knows about to see if a new 818 * geom instance of this class needs to be created (in case the provider 819 * is first from a (possibly) multi-consumer geom) or it just needs 820 * to be added to an existing instance. */ 821 sc = NULL; 822 gp = NULL; 823 LIST_FOREACH(gp, &mp->geom, geom) { 824 sc = gp->softc; 825 if (sc == NULL) 826 continue; 827 if (strcmp(md.md_name, sc->geom->name) != 0) 828 continue; 829 if (md.md_id != sc->id) 830 continue; 831 break; 832 } 833 if (gp != NULL) { /* We found an existing geom instance; add to it */ 834 LOG_MSG(LVL_INFO, "Adding %s to %s", pp->name, md.md_name); 835 error = add_provider_to_geom(sc, pp, &md); 836 if (error != 0) { 837 LOG_MSG(LVL_ERROR, "Error adding %s to %s (error %d)", 838 pp->name, md.md_name, error); 839 return (NULL); 840 } 841 } else { /* New geom instance needs to be created */ 842 gp = create_virstor_geom(mp, &md); 843 if (gp == NULL) { 844 LOG_MSG(LVL_ERROR, "Error creating new instance of " 845 "class %s: %s", mp->name, md.md_name); 846 LOG_MSG(LVL_DEBUG, "Error creating %s at %s", 847 md.md_name, pp->name); 848 return (NULL); 849 } 850 sc = gp->softc; 851 LOG_MSG(LVL_INFO, "Adding %s to %s (first found)", pp->name, 852 md.md_name); 853 error = add_provider_to_geom(sc, pp, &md); 854 if (error != 0) { 855 LOG_MSG(LVL_ERROR, "Error adding %s to %s (error %d)", 856 pp->name, md.md_name, error); 857 virstor_geom_destroy(sc, TRUE, FALSE); 858 return (NULL); 859 } 860 } 861 862 return (gp); 863} 864 865/* 866 * Destroyes consumer passed to it in arguments. Used as a callback 867 * on g_event queue. 868 */ 869static void 870delay_destroy_consumer(void *arg, int flags __unused) 871{ 872 struct g_consumer *c = arg; 873 KASSERT(c != NULL, ("%s: invalid consumer", __func__)); 874 LOG_MSG(LVL_DEBUG, "Consumer %s destroyed with delay", 875 c->provider->name); 876 g_detach(c); 877 g_destroy_consumer(c); 878} 879 880/* 881 * Remove a component (consumer) from geom instance; If it's the first 882 * component being removed, orphan the provider to announce geom's being 883 * dismantled 884 */ 885static void 886remove_component(struct g_virstor_softc *sc, struct g_virstor_component *comp, 887 boolean_t delay) 888{ 889 struct g_consumer *c; 890 891 KASSERT(comp->gcons != NULL, ("Component with no consumer in %s", 892 sc->geom->name)); 893 c = comp->gcons; 894 895 comp->gcons = NULL; 896 KASSERT(c->provider != NULL, ("%s: no provider", __func__)); 897 LOG_MSG(LVL_DEBUG, "Component %s removed from %s", c->provider->name, 898 sc->geom->name); 899 if (sc->provider != NULL) { 900 /* Whither, GEOM? */ 901 sc->provider->flags |= G_PF_WITHER; 902 g_orphan_provider(sc->provider, ENXIO); 903 sc->provider = NULL; 904 LOG_MSG(LVL_INFO, "Removing provider %s", sc->geom->name); 905 } 906 907 if (c->acr > 0 || c->acw > 0 || c->ace > 0) 908 g_access(c, -c->acr, -c->acw, -c->ace); 909 if (delay) { 910 /* Destroy consumer after it's tasted */ 911 g_post_event(delay_destroy_consumer, c, M_WAITOK, NULL); 912 } else { 913 g_detach(c); 914 g_destroy_consumer(c); 915 } 916} 917 918/* 919 * Destroy geom - called internally 920 * See g_virstor_destroy_geom for the other one 921 */ 922static int 923virstor_geom_destroy(struct g_virstor_softc *sc, boolean_t force, 924 boolean_t delay) 925{ 926 struct g_provider *pp; 927 struct g_geom *gp; 928 int n; 929 930 g_topology_assert(); 931 932 if (sc == NULL) 933 return (ENXIO); 934 935 pp = sc->provider; 936 if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) { 937 LOG_MSG(force ? LVL_WARNING : LVL_ERROR, 938 "Device %s is still open.", pp->name); 939 if (!force) 940 return (EBUSY); 941 } 942 943 for (n = 0; n < sc->n_components; n++) { 944 if (sc->components[n].gcons != NULL) 945 remove_component(sc, &sc->components[n], delay); 946 } 947 948 gp = sc->geom; 949 gp->softc = NULL; 950 951 KASSERT(sc->provider == NULL, ("Provider still exists for %s", 952 gp->name)); 953 954 /* XXX: This might or might not work, since we're called with 955 * the topology lock held. Also, it might panic the kernel if 956 * the error'd BIO is in softupdates code. */ 957 mtx_lock(&sc->delayed_bio_q_mtx); 958 while (!STAILQ_EMPTY(&sc->delayed_bio_q)) { 959 struct g_virstor_bio_q *bq; 960 bq = STAILQ_FIRST(&sc->delayed_bio_q); 961 bq->bio->bio_error = ENOSPC; 962 g_io_deliver(bq->bio, EIO); 963 STAILQ_REMOVE_HEAD(&sc->delayed_bio_q, linkage); 964 free(bq, M_GVIRSTOR); 965 } 966 mtx_unlock(&sc->delayed_bio_q_mtx); 967 mtx_destroy(&sc->delayed_bio_q_mtx); 968 969 free(sc->map, M_GVIRSTOR); 970 free(sc->components, M_GVIRSTOR); 971 bzero(sc, sizeof *sc); 972 free(sc, M_GVIRSTOR); 973 974 pp = LIST_FIRST(&gp->provider); /* We only offer one provider */ 975 if (pp == NULL || (pp->acr == 0 && pp->acw == 0 && pp->ace == 0)) 976 LOG_MSG(LVL_DEBUG, "Device %s destroyed", gp->name); 977 978 g_wither_geom(gp, ENXIO); 979 980 return (0); 981} 982 983/* 984 * Utility function: read metadata & decode. Wants topology lock to be 985 * held. 986 */ 987static int 988read_metadata(struct g_consumer *cp, struct g_virstor_metadata *md) 989{ 990 struct g_provider *pp; 991 char *buf; 992 int error; 993 994 g_topology_assert(); 995 error = g_access(cp, 1, 0, 0); 996 if (error != 0) 997 return (error); 998 pp = cp->provider; 999 g_topology_unlock(); 1000 buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize, 1001 &error); 1002 g_topology_lock(); 1003 g_access(cp, -1, 0, 0); 1004 if (buf == NULL) 1005 return (error); 1006 1007 virstor_metadata_decode(buf, md); 1008 g_free(buf); 1009 1010 return (0); 1011} 1012 1013/** 1014 * Utility function: encode & write metadata. Assumes topology lock is 1015 * held. 1016 * 1017 * There is no useful way of recovering from errors in this function, 1018 * not involving panicking the kernel. If the metadata cannot be written 1019 * the most we can do is notify the operator and hope he spots it and 1020 * replaces the broken drive. 1021 */ 1022static void 1023write_metadata(struct g_consumer *cp, struct g_virstor_metadata *md) 1024{ 1025 struct g_provider *pp; 1026 char *buf; 1027 int error; 1028 1029 KASSERT(cp != NULL && md != NULL && cp->provider != NULL, 1030 ("Something's fishy in %s", __func__)); 1031 LOG_MSG(LVL_DEBUG, "Writing metadata on %s", cp->provider->name); 1032 g_topology_assert(); 1033 error = g_access(cp, 0, 1, 0); 1034 if (error != 0) { 1035 LOG_MSG(LVL_ERROR, "g_access(0,1,0) failed for %s: %d", 1036 cp->provider->name, error); 1037 return; 1038 } 1039 pp = cp->provider; 1040 1041 buf = malloc(pp->sectorsize, M_GVIRSTOR, M_WAITOK); 1042 virstor_metadata_encode(md, buf); 1043 g_topology_unlock(); 1044 error = g_write_data(cp, pp->mediasize - pp->sectorsize, buf, 1045 pp->sectorsize); 1046 g_topology_lock(); 1047 g_access(cp, 0, -1, 0); 1048 free(buf, M_GVIRSTOR); 1049 1050 if (error != 0) 1051 LOG_MSG(LVL_ERROR, "Error %d writing metadata to %s", 1052 error, cp->provider->name); 1053} 1054 1055/* 1056 * Creates a new instance of this GEOM class, initialise softc 1057 */ 1058static struct g_geom * 1059create_virstor_geom(struct g_class *mp, struct g_virstor_metadata *md) 1060{ 1061 struct g_geom *gp; 1062 struct g_virstor_softc *sc; 1063 1064 LOG_MSG(LVL_DEBUG, "Creating geom instance for %s (id=%u)", 1065 md->md_name, md->md_id); 1066 1067 if (md->md_count < 1 || md->md_chunk_size < 1 || 1068 md->md_virsize < md->md_chunk_size) { 1069 /* This is bogus configuration, and probably means data is 1070 * somehow corrupted. Panic, maybe? */ 1071 LOG_MSG(LVL_ERROR, "Nonsensical metadata information for %s", 1072 md->md_name); 1073 return (NULL); 1074 } 1075 1076 /* Check if it's already created */ 1077 LIST_FOREACH(gp, &mp->geom, geom) { 1078 sc = gp->softc; 1079 if (sc != NULL && strcmp(sc->geom->name, md->md_name) == 0) { 1080 LOG_MSG(LVL_WARNING, "Geom %s already exists", 1081 md->md_name); 1082 if (sc->id != md->md_id) { 1083 LOG_MSG(LVL_ERROR, 1084 "Some stale or invalid components " 1085 "exist for virstor device named %s. " 1086 "You will need to <CLEAR> all stale " 1087 "components and maybe reconfigure " 1088 "the virstor device. Tune " 1089 "kern.geom.virstor.debug sysctl up " 1090 "for more information.", 1091 sc->geom->name); 1092 } 1093 return (NULL); 1094 } 1095 } 1096 gp = g_new_geomf(mp, "%s", md->md_name); 1097 gp->softc = NULL; /* to circumevent races that test softc */ 1098 1099 gp->start = g_virstor_start; 1100 gp->spoiled = g_virstor_orphan; 1101 gp->orphan = g_virstor_orphan; 1102 gp->access = g_virstor_access; 1103 gp->dumpconf = g_virstor_dumpconf; 1104 1105 sc = malloc(sizeof(*sc), M_GVIRSTOR, M_WAITOK | M_ZERO); 1106 sc->id = md->md_id; 1107 sc->n_components = md->md_count; 1108 sc->components = malloc(sizeof(struct g_virstor_component) * md->md_count, 1109 M_GVIRSTOR, M_WAITOK | M_ZERO); 1110 sc->chunk_size = md->md_chunk_size; 1111 sc->virsize = md->md_virsize; 1112 STAILQ_INIT(&sc->delayed_bio_q); 1113 mtx_init(&sc->delayed_bio_q_mtx, "gvirstor_delayed_bio_q_mtx", 1114 "gvirstor", MTX_DEF | MTX_RECURSE); 1115 1116 sc->geom = gp; 1117 sc->provider = NULL; /* virstor_check_and_run will create it */ 1118 gp->softc = sc; 1119 1120 LOG_MSG(LVL_ANNOUNCE, "Device %s created", sc->geom->name); 1121 1122 return (gp); 1123} 1124 1125/* 1126 * Add provider to a GEOM class instance 1127 */ 1128static int 1129add_provider_to_geom(struct g_virstor_softc *sc, struct g_provider *pp, 1130 struct g_virstor_metadata *md) 1131{ 1132 struct g_virstor_component *component; 1133 struct g_consumer *cp, *fcp; 1134 struct g_geom *gp; 1135 int error; 1136 1137 if (md->no >= sc->n_components) 1138 return (EINVAL); 1139 1140 /* "Current" compontent */ 1141 component = &(sc->components[md->no]); 1142 if (component->gcons != NULL) 1143 return (EEXIST); 1144 1145 gp = sc->geom; 1146 fcp = LIST_FIRST(&gp->consumer); 1147 1148 cp = g_new_consumer(gp); 1149 error = g_attach(cp, pp); 1150 1151 if (error != 0) { 1152 g_destroy_consumer(cp); 1153 return (error); 1154 } 1155 1156 if (fcp != NULL) { 1157 if (fcp->provider->sectorsize != pp->sectorsize) { 1158 /* TODO: this can be made to work */ 1159 LOG_MSG(LVL_ERROR, "Provider %s of %s has invalid " 1160 "sector size (%d)", pp->name, sc->geom->name, 1161 pp->sectorsize); 1162 return (EINVAL); 1163 } 1164 if (fcp->acr > 0 || fcp->acw || fcp->ace > 0) { 1165 /* Replicate access permissions from first "live" consumer 1166 * to the new one */ 1167 error = g_access(cp, fcp->acr, fcp->acw, fcp->ace); 1168 if (error != 0) { 1169 g_detach(cp); 1170 g_destroy_consumer(cp); 1171 return (error); 1172 } 1173 } 1174 } 1175 1176 /* Bring up a new component */ 1177 cp->private = component; 1178 component->gcons = cp; 1179 component->sc = sc; 1180 component->index = md->no; 1181 component->chunk_count = md->chunk_count; 1182 component->chunk_next = md->chunk_next; 1183 component->chunk_reserved = md->chunk_reserved; 1184 component->flags = md->flags; 1185 1186 LOG_MSG(LVL_DEBUG, "%s attached to %s", pp->name, sc->geom->name); 1187 1188 virstor_check_and_run(sc); 1189 return (0); 1190} 1191 1192/* 1193 * Check if everything's ready to create the geom provider & device entry, 1194 * create and start provider. 1195 * Called ultimately by .taste, from g_event thread 1196 */ 1197static void 1198virstor_check_and_run(struct g_virstor_softc *sc) 1199{ 1200 off_t off; 1201 size_t n, count; 1202 int index; 1203 int error; 1204 1205 if (virstor_valid_components(sc) != sc->n_components) 1206 return; 1207 1208 if (virstor_valid_components(sc) == 0) { 1209 /* This is actually a candidate for panic() */ 1210 LOG_MSG(LVL_ERROR, "No valid components for %s?", 1211 sc->provider->name); 1212 return; 1213 } 1214 1215 sc->sectorsize = sc->components[0].gcons->provider->sectorsize; 1216 1217 /* Initialise allocation map from the first consumer */ 1218 sc->chunk_count = sc->virsize / sc->chunk_size; 1219 if (sc->chunk_count * (off_t)sc->chunk_size != sc->virsize) { 1220 LOG_MSG(LVL_WARNING, "Device %s truncated to %ju bytes", 1221 sc->provider->name, 1222 sc->chunk_count * (off_t)sc->chunk_size); 1223 } 1224 sc->map_size = sc->chunk_count * sizeof *(sc->map); 1225 /* The following allocation is in order of 4MB - 8MB */ 1226 sc->map = malloc(sc->map_size, M_GVIRSTOR, M_WAITOK); 1227 KASSERT(sc->map != NULL, ("%s: Memory allocation error (%zu bytes) for %s", 1228 __func__, sc->map_size, sc->provider->name)); 1229 sc->map_sectors = sc->map_size / sc->sectorsize; 1230 1231 count = 0; 1232 for (n = 0; n < sc->n_components; n++) 1233 count += sc->components[n].chunk_count; 1234 LOG_MSG(LVL_INFO, "Device %s has %zu physical chunks and %zu virtual " 1235 "(%zu KB chunks)", 1236 sc->geom->name, count, sc->chunk_count, sc->chunk_size / 1024); 1237 1238 error = g_access(sc->components[0].gcons, 1, 0, 0); 1239 if (error != 0) { 1240 LOG_MSG(LVL_ERROR, "Cannot acquire read access for %s to " 1241 "read allocation map for %s", 1242 sc->components[0].gcons->provider->name, 1243 sc->geom->name); 1244 return; 1245 } 1246 /* Read in the allocation map */ 1247 LOG_MSG(LVL_DEBUG, "Reading map for %s from %s", sc->geom->name, 1248 sc->components[0].gcons->provider->name); 1249 off = count = n = 0; 1250 while (count < sc->map_size) { 1251 struct g_virstor_map_entry *mapbuf; 1252 size_t bs; 1253 1254 bs = MIN(MAXPHYS, sc->map_size - count); 1255 if (bs % sc->sectorsize != 0) { 1256 /* Check for alignment errors */ 1257 bs = (bs / sc->sectorsize) * sc->sectorsize; 1258 if (bs == 0) 1259 break; 1260 LOG_MSG(LVL_ERROR, "Trouble: map is not sector-aligned " 1261 "for %s on %s", sc->geom->name, 1262 sc->components[0].gcons->provider->name); 1263 } 1264 mapbuf = g_read_data(sc->components[0].gcons, off, bs, &error); 1265 if (mapbuf == NULL) { 1266 free(sc->map, M_GVIRSTOR); 1267 LOG_MSG(LVL_ERROR, "Error reading allocation map " 1268 "for %s from %s (offset %ju) (error %d)", 1269 sc->geom->name, 1270 sc->components[0].gcons->provider->name, 1271 off, error); 1272 return; 1273 } 1274 1275 bcopy(mapbuf, &sc->map[n], bs); 1276 off += bs; 1277 count += bs; 1278 n += bs / sizeof *(sc->map); 1279 g_free(mapbuf); 1280 } 1281 g_access(sc->components[0].gcons, -1, 0, 0); 1282 LOG_MSG(LVL_DEBUG, "Read map for %s", sc->geom->name); 1283 1284 /* find first component with allocatable chunks */ 1285 index = -1; 1286 for (n = 0; n < sc->n_components; n++) { 1287 if (sc->components[n].chunk_next < 1288 sc->components[n].chunk_count) { 1289 index = n; 1290 break; 1291 } 1292 } 1293 if (index == -1) 1294 /* not found? set it to the last component and handle it 1295 * later */ 1296 index = sc->n_components - 1; 1297 1298 if (index >= sc->n_components - g_virstor_component_watermark - 1) { 1299 LOG_MSG(LVL_WARNING, "Device %s running out of components " 1300 "(%d/%u: %s)", sc->geom->name, 1301 index+1, 1302 sc->n_components, 1303 sc->components[index].gcons->provider->name); 1304 } 1305 sc->curr_component = index; 1306 1307 if (sc->components[index].chunk_next >= 1308 sc->components[index].chunk_count - g_virstor_chunk_watermark) { 1309 LOG_MSG(LVL_WARNING, 1310 "Component %s of %s is running out of free space " 1311 "(%u chunks left)", 1312 sc->components[index].gcons->provider->name, 1313 sc->geom->name, sc->components[index].chunk_count - 1314 sc->components[index].chunk_next); 1315 } 1316 1317 sc->me_per_sector = sc->sectorsize / sizeof *(sc->map); 1318 if (sc->sectorsize % sizeof *(sc->map) != 0) { 1319 LOG_MSG(LVL_ERROR, 1320 "%s: Map entries don't fit exactly in a sector (%s)", 1321 __func__, sc->geom->name); 1322 return; 1323 } 1324 1325 /* Recalculate allocated chunks in components & at the same time 1326 * verify map data is sane. We could trust metadata on this, but 1327 * we want to make sure. */ 1328 for (n = 0; n < sc->n_components; n++) 1329 sc->components[n].chunk_next = sc->components[n].chunk_reserved; 1330 1331 for (n = 0; n < sc->chunk_count; n++) { 1332 if (sc->map[n].provider_no >= sc->n_components || 1333 sc->map[n].provider_chunk >= 1334 sc->components[sc->map[n].provider_no].chunk_count) { 1335 LOG_MSG(LVL_ERROR, "%s: Invalid entry %u in map for %s", 1336 __func__, (u_int)n, sc->geom->name); 1337 LOG_MSG(LVL_ERROR, "%s: provider_no: %u, n_components: %u" 1338 " provider_chunk: %u, chunk_count: %u", __func__, 1339 sc->map[n].provider_no, sc->n_components, 1340 sc->map[n].provider_chunk, 1341 sc->components[sc->map[n].provider_no].chunk_count); 1342 return; 1343 } 1344 if (sc->map[n].flags & VIRSTOR_MAP_ALLOCATED) 1345 sc->components[sc->map[n].provider_no].chunk_next++; 1346 } 1347 1348 sc->provider = g_new_providerf(sc->geom, "virstor/%s", 1349 sc->geom->name); 1350 1351 sc->provider->sectorsize = sc->sectorsize; 1352 sc->provider->mediasize = sc->virsize; 1353 g_error_provider(sc->provider, 0); 1354 1355 LOG_MSG(LVL_INFO, "%s activated", sc->provider->name); 1356 LOG_MSG(LVL_DEBUG, "%s starting with current component %u, starting " 1357 "chunk %u", sc->provider->name, sc->curr_component, 1358 sc->components[sc->curr_component].chunk_next); 1359} 1360 1361/* 1362 * Returns count of active providers in this geom instance 1363 */ 1364static u_int 1365virstor_valid_components(struct g_virstor_softc *sc) 1366{ 1367 unsigned int nc, i; 1368 1369 nc = 0; 1370 KASSERT(sc != NULL, ("%s: softc is NULL", __func__)); 1371 KASSERT(sc->components != NULL, ("%s: sc->components is NULL", __func__)); 1372 for (i = 0; i < sc->n_components; i++) 1373 if (sc->components[i].gcons != NULL) 1374 nc++; 1375 return (nc); 1376} 1377 1378/* 1379 * Called when the consumer gets orphaned (?) 1380 */ 1381static void 1382g_virstor_orphan(struct g_consumer *cp) 1383{ 1384 struct g_virstor_softc *sc; 1385 struct g_virstor_component *comp; 1386 struct g_geom *gp; 1387 1388 g_topology_assert(); 1389 gp = cp->geom; 1390 sc = gp->softc; 1391 if (sc == NULL) 1392 return; 1393 1394 comp = cp->private; 1395 KASSERT(comp != NULL, ("%s: No component in private part of consumer", 1396 __func__)); 1397 remove_component(sc, comp, FALSE); 1398 if (virstor_valid_components(sc) == 0) 1399 virstor_geom_destroy(sc, TRUE, FALSE); 1400} 1401 1402/* 1403 * Called to notify geom when it's been opened, and for what intent 1404 */ 1405static int 1406g_virstor_access(struct g_provider *pp, int dr, int dw, int de) 1407{ 1408 struct g_consumer *c; 1409 struct g_virstor_softc *sc; 1410 struct g_geom *gp; 1411 int error; 1412 1413 KASSERT(pp != NULL, ("%s: NULL provider", __func__)); 1414 gp = pp->geom; 1415 KASSERT(gp != NULL, ("%s: NULL geom", __func__)); 1416 sc = gp->softc; 1417 1418 if (sc == NULL) { 1419 /* It seems that .access can be called with negative dr,dw,dx 1420 * in this case but I want to check for myself */ 1421 LOG_MSG(LVL_WARNING, "access(%d, %d, %d) for %s", 1422 dr, dw, de, pp->name); 1423 /* This should only happen when geom is withered so 1424 * allow only negative requests */ 1425 KASSERT(dr <= 0 && dw <= 0 && de <= 0, 1426 ("%s: Positive access for %s", __func__, pp->name)); 1427 if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0) 1428 LOG_MSG(LVL_DEBUG, "Device %s definitely destroyed", 1429 pp->name); 1430 return (0); 1431 } 1432 1433 /* Grab an exclusive bit to propagate on our consumers on first open */ 1434 if (pp->acr == 0 && pp->acw == 0 && pp->ace == 0) 1435 de++; 1436 /* ... drop it on close */ 1437 if (pp->acr + dr == 0 && pp->acw + dw == 0 && pp->ace + de == 0) { 1438 de--; 1439 update_metadata(sc); /* Writes statistical information */ 1440 } 1441 1442 error = ENXIO; 1443 LIST_FOREACH(c, &gp->consumer, consumer) { 1444 KASSERT(c != NULL, ("%s: consumer is NULL", __func__)); 1445 error = g_access(c, dr, dw, de); 1446 if (error != 0) { 1447 struct g_consumer *c2; 1448 1449 /* Backout earlier changes */ 1450 LIST_FOREACH(c2, &gp->consumer, consumer) { 1451 if (c2 == c) /* all eariler components fixed */ 1452 return (error); 1453 g_access(c2, -dr, -dw, -de); 1454 } 1455 } 1456 } 1457 1458 return (error); 1459} 1460 1461/* 1462 * Generate XML dump of current state 1463 */ 1464static void 1465g_virstor_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp, 1466 struct g_consumer *cp, struct g_provider *pp) 1467{ 1468 struct g_virstor_softc *sc; 1469 1470 g_topology_assert(); 1471 sc = gp->softc; 1472 1473 if (sc == NULL || pp != NULL) 1474 return; 1475 1476 if (cp != NULL) { 1477 /* For each component */ 1478 struct g_virstor_component *comp; 1479 1480 comp = cp->private; 1481 if (comp == NULL) 1482 return; 1483 sbuf_printf(sb, "%s<ComponentIndex>%u</ComponentIndex>\n", 1484 indent, comp->index); 1485 sbuf_printf(sb, "%s<ChunkCount>%u</ChunkCount>\n", 1486 indent, comp->chunk_count); 1487 sbuf_printf(sb, "%s<ChunksUsed>%u</ChunksUsed>\n", 1488 indent, comp->chunk_next); 1489 sbuf_printf(sb, "%s<ChunksReserved>%u</ChunksReserved>\n", 1490 indent, comp->chunk_reserved); 1491 sbuf_printf(sb, "%s<StorageFree>%u%%</StorageFree>\n", 1492 indent, 1493 comp->chunk_next > 0 ? 100 - 1494 ((comp->chunk_next + comp->chunk_reserved) * 100) / 1495 comp->chunk_count : 100); 1496 } else { 1497 /* For the whole thing */ 1498 u_int count, used, i; 1499 off_t size; 1500 1501 count = used = size = 0; 1502 for (i = 0; i < sc->n_components; i++) { 1503 if (sc->components[i].gcons != NULL) { 1504 count += sc->components[i].chunk_count; 1505 used += sc->components[i].chunk_next + 1506 sc->components[i].chunk_reserved; 1507 size += sc->components[i].gcons-> 1508 provider->mediasize; 1509 } 1510 } 1511 1512 sbuf_printf(sb, "%s<Status>" 1513 "Components=%u, Online=%u</Status>\n", indent, 1514 sc->n_components, virstor_valid_components(sc)); 1515 sbuf_printf(sb, "%s<State>%u%% physical free</State>\n", 1516 indent, 100-(used * 100) / count); 1517 sbuf_printf(sb, "%s<ChunkSize>%zu</ChunkSize>\n", indent, 1518 sc->chunk_size); 1519 sbuf_printf(sb, "%s<PhysicalFree>%u%%</PhysicalFree>\n", 1520 indent, used > 0 ? 100 - (used * 100) / count : 100); 1521 sbuf_printf(sb, "%s<ChunkPhysicalCount>%u</ChunkPhysicalCount>\n", 1522 indent, count); 1523 sbuf_printf(sb, "%s<ChunkVirtualCount>%zu</ChunkVirtualCount>\n", 1524 indent, sc->chunk_count); 1525 sbuf_printf(sb, "%s<PhysicalBacking>%zu%%</PhysicalBacking>\n", 1526 indent, 1527 (count * 100) / sc->chunk_count); 1528 sbuf_printf(sb, "%s<PhysicalBackingSize>%jd</PhysicalBackingSize>\n", 1529 indent, size); 1530 sbuf_printf(sb, "%s<VirtualSize>%jd</VirtualSize>\n", indent, 1531 sc->virsize); 1532 } 1533} 1534 1535/* 1536 * GEOM .done handler 1537 * Can't use standard handler because one requested IO may 1538 * fork into additional data IOs 1539 */ 1540static void 1541g_virstor_done(struct bio *b) 1542{ 1543 struct g_virstor_softc *sc; 1544 struct bio *parent_b; 1545 1546 parent_b = b->bio_parent; 1547 sc = parent_b->bio_to->geom->softc; 1548 1549 if (b->bio_error != 0) { 1550 LOG_MSG(LVL_ERROR, "Error %d for offset=%ju, length=%ju, %s", 1551 b->bio_error, b->bio_offset, b->bio_length, 1552 b->bio_to->name); 1553 if (parent_b->bio_error == 0) 1554 parent_b->bio_error = b->bio_error; 1555 } 1556 1557 parent_b->bio_inbed++; 1558 parent_b->bio_completed += b->bio_completed; 1559 1560 if (parent_b->bio_children == parent_b->bio_inbed) { 1561 parent_b->bio_completed = parent_b->bio_length; 1562 g_io_deliver(parent_b, parent_b->bio_error); 1563 } 1564 g_destroy_bio(b); 1565} 1566 1567/* 1568 * I/O starts here 1569 * Called in g_down thread 1570 */ 1571static void 1572g_virstor_start(struct bio *b) 1573{ 1574 struct g_virstor_softc *sc; 1575 struct g_virstor_component *comp; 1576 struct bio *cb; 1577 struct g_provider *pp; 1578 char *addr; 1579 off_t offset, length; 1580 struct bio_queue_head bq; 1581 size_t chunk_size; /* cached for convenience */ 1582 u_int count; 1583 1584 pp = b->bio_to; 1585 sc = pp->geom->softc; 1586 KASSERT(sc != NULL, ("%s: no softc (error=%d, device=%s)", __func__, 1587 b->bio_to->error, b->bio_to->name)); 1588 1589 LOG_REQ(LVL_MOREDEBUG, b, "%s", __func__); 1590 1591 switch (b->bio_cmd) { 1592 case BIO_READ: 1593 case BIO_WRITE: 1594 case BIO_DELETE: 1595 break; 1596 default: 1597 g_io_deliver(b, EOPNOTSUPP); 1598 return; 1599 } 1600 1601 LOG_MSG(LVL_DEBUG2, "BIO arrived, size=%ju", b->bio_length); 1602 bioq_init(&bq); 1603 1604 chunk_size = sc->chunk_size; 1605 addr = b->bio_data; 1606 offset = b->bio_offset; /* virtual offset and length */ 1607 length = b->bio_length; 1608 1609 while (length > 0) { 1610 size_t chunk_index, in_chunk_offset, in_chunk_length; 1611 struct virstor_map_entry *me; 1612 1613 chunk_index = offset / chunk_size; /* round downwards */ 1614 in_chunk_offset = offset % chunk_size; 1615 in_chunk_length = min(length, chunk_size - in_chunk_offset); 1616 LOG_MSG(LVL_DEBUG, "Mapped %s(%ju, %ju) to (%zu,%zu,%zu)", 1617 b->bio_cmd == BIO_READ ? "R" : "W", 1618 offset, length, 1619 chunk_index, in_chunk_offset, in_chunk_length); 1620 me = &sc->map[chunk_index]; 1621 1622 if (b->bio_cmd == BIO_READ || b->bio_cmd == BIO_DELETE) { 1623 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) { 1624 /* Reads from unallocated chunks return zeroed 1625 * buffers */ 1626 if (b->bio_cmd == BIO_READ) 1627 bzero(addr, in_chunk_length); 1628 } else { 1629 comp = &sc->components[me->provider_no]; 1630 1631 cb = g_clone_bio(b); 1632 if (cb == NULL) { 1633 bioq_dismantle(&bq); 1634 if (b->bio_error == 0) 1635 b->bio_error = ENOMEM; 1636 g_io_deliver(b, b->bio_error); 1637 return; 1638 } 1639 cb->bio_to = comp->gcons->provider; 1640 cb->bio_done = g_virstor_done; 1641 cb->bio_offset = 1642 (off_t)me->provider_chunk * (off_t)chunk_size 1643 + in_chunk_offset; 1644 cb->bio_length = in_chunk_length; 1645 cb->bio_data = addr; 1646 cb->bio_caller1 = comp; 1647 bioq_disksort(&bq, cb); 1648 } 1649 } else { /* handle BIO_WRITE */ 1650 KASSERT(b->bio_cmd == BIO_WRITE, 1651 ("%s: Unknown command %d", __func__, 1652 b->bio_cmd)); 1653 1654 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) { 1655 /* We have a virtual chunk, represented by 1656 * the "me" entry, but it's not yet allocated 1657 * (tied to) a physical chunk. So do it now. */ 1658 struct virstor_map_entry *data_me; 1659 u_int phys_chunk, comp_no; 1660 off_t s_offset; 1661 int error; 1662 1663 error = allocate_chunk(sc, &comp, &comp_no, 1664 &phys_chunk); 1665 if (error != 0) { 1666 /* We cannot allocate a physical chunk 1667 * to satisfy this request, so we'll 1668 * delay it to when we can... 1669 * XXX: this will prevent the fs from 1670 * being umounted! */ 1671 struct g_virstor_bio_q *biq; 1672 biq = malloc(sizeof *biq, M_GVIRSTOR, 1673 M_NOWAIT); 1674 if (biq == NULL) { 1675 bioq_dismantle(&bq); 1676 if (b->bio_error == 0) 1677 b->bio_error = ENOMEM; 1678 g_io_deliver(b, b->bio_error); 1679 return; 1680 } 1681 biq->bio = b; 1682 mtx_lock(&sc->delayed_bio_q_mtx); 1683 STAILQ_INSERT_TAIL(&sc->delayed_bio_q, 1684 biq, linkage); 1685 mtx_unlock(&sc->delayed_bio_q_mtx); 1686 LOG_MSG(LVL_WARNING, "Delaying BIO " 1687 "(size=%ju) until free physical " 1688 "space can be found on %s", 1689 b->bio_length, 1690 sc->provider->name); 1691 return; 1692 } 1693 LOG_MSG(LVL_DEBUG, "Allocated chunk %u on %s " 1694 "for %s", 1695 phys_chunk, 1696 comp->gcons->provider->name, 1697 sc->provider->name); 1698 1699 me->provider_no = comp_no; 1700 me->provider_chunk = phys_chunk; 1701 me->flags |= VIRSTOR_MAP_ALLOCATED; 1702 1703 cb = g_clone_bio(b); 1704 if (cb == NULL) { 1705 me->flags &= ~VIRSTOR_MAP_ALLOCATED; 1706 me->provider_no = 0; 1707 me->provider_chunk = 0; 1708 bioq_dismantle(&bq); 1709 if (b->bio_error == 0) 1710 b->bio_error = ENOMEM; 1711 g_io_deliver(b, b->bio_error); 1712 return; 1713 } 1714 1715 /* The allocation table is stored continuously 1716 * at the start of the drive. We need to 1717 * calculate the offset of the sector that holds 1718 * this map entry both on the drive and in the 1719 * map array. 1720 * sc_offset will end up pointing to the drive 1721 * sector. */ 1722 s_offset = chunk_index * sizeof *me; 1723 s_offset = (s_offset / sc->sectorsize) * 1724 sc->sectorsize; 1725 1726 /* data_me points to map entry sector 1727 * in memory (analoguos to offset) */ 1728 data_me = &sc->map[(chunk_index / 1729 sc->me_per_sector) * sc->me_per_sector]; 1730 1731 /* Commit sector with map entry to storage */ 1732 cb->bio_to = sc->components[0].gcons->provider; 1733 cb->bio_done = g_virstor_done; 1734 cb->bio_offset = s_offset; 1735 cb->bio_data = (char *)data_me; 1736 cb->bio_length = sc->sectorsize; 1737 cb->bio_caller1 = &sc->components[0]; 1738 bioq_disksort(&bq, cb); 1739 } 1740 1741 comp = &sc->components[me->provider_no]; 1742 cb = g_clone_bio(b); 1743 if (cb == NULL) { 1744 bioq_dismantle(&bq); 1745 if (b->bio_error == 0) 1746 b->bio_error = ENOMEM; 1747 g_io_deliver(b, b->bio_error); 1748 return; 1749 } 1750 /* Finally, handle the data */ 1751 cb->bio_to = comp->gcons->provider; 1752 cb->bio_done = g_virstor_done; 1753 cb->bio_offset = (off_t)me->provider_chunk*(off_t)chunk_size + 1754 in_chunk_offset; 1755 cb->bio_length = in_chunk_length; 1756 cb->bio_data = addr; 1757 cb->bio_caller1 = comp; 1758 bioq_disksort(&bq, cb); 1759 } 1760 addr += in_chunk_length; 1761 length -= in_chunk_length; 1762 offset += in_chunk_length; 1763 } 1764 1765 /* Fire off bio's here */ 1766 count = 0; 1767 for (cb = bioq_first(&bq); cb != NULL; cb = bioq_first(&bq)) { 1768 bioq_remove(&bq, cb); 1769 LOG_REQ(LVL_MOREDEBUG, cb, "Firing request"); 1770 comp = cb->bio_caller1; 1771 cb->bio_caller1 = NULL; 1772 LOG_MSG(LVL_DEBUG, " firing bio, offset=%ju, length=%ju", 1773 cb->bio_offset, cb->bio_length); 1774 g_io_request(cb, comp->gcons); 1775 count++; 1776 } 1777 if (count == 0) { /* We handled everything locally */ 1778 b->bio_completed = b->bio_length; 1779 g_io_deliver(b, 0); 1780 } 1781 1782} 1783 1784/* 1785 * Allocate a chunk from a physical provider. Returns physical component, 1786 * chunk index relative to the component and the component's index. 1787 */ 1788static int 1789allocate_chunk(struct g_virstor_softc *sc, struct g_virstor_component **comp, 1790 u_int *comp_no_p, u_int *chunk) 1791{ 1792 u_int comp_no; 1793 1794 KASSERT(sc->curr_component < sc->n_components, 1795 ("%s: Invalid curr_component: %u", __func__, sc->curr_component)); 1796 1797 comp_no = sc->curr_component; 1798 *comp = &sc->components[comp_no]; 1799 dump_component(*comp); 1800 if ((*comp)->chunk_next >= (*comp)->chunk_count) { 1801 /* This component is full. Allocate next component */ 1802 if (comp_no >= sc->n_components-1) { 1803 LOG_MSG(LVL_ERROR, "All physical space allocated for %s", 1804 sc->geom->name); 1805 return (-1); 1806 } 1807 (*comp)->flags &= ~VIRSTOR_PROVIDER_CURRENT; 1808 sc->curr_component = ++comp_no; 1809 1810 *comp = &sc->components[comp_no]; 1811 if (comp_no >= sc->n_components - g_virstor_component_watermark-1) 1812 LOG_MSG(LVL_WARNING, "Device %s running out of components " 1813 "(switching to %u/%u: %s)", sc->geom->name, 1814 comp_no+1, sc->n_components, 1815 (*comp)->gcons->provider->name); 1816 /* Take care not to overwrite reserved chunks */ 1817 if ( (*comp)->chunk_reserved > 0 && 1818 (*comp)->chunk_next < (*comp)->chunk_reserved) 1819 (*comp)->chunk_next = (*comp)->chunk_reserved; 1820 1821 (*comp)->flags |= 1822 VIRSTOR_PROVIDER_ALLOCATED | VIRSTOR_PROVIDER_CURRENT; 1823 dump_component(*comp); 1824 *comp_no_p = comp_no; 1825 *chunk = (*comp)->chunk_next++; 1826 } else { 1827 *comp_no_p = comp_no; 1828 *chunk = (*comp)->chunk_next++; 1829 } 1830 return (0); 1831} 1832 1833/* Dump a component */ 1834static void 1835dump_component(struct g_virstor_component *comp) 1836{ 1837 1838 if (g_virstor_debug < LVL_DEBUG2) 1839 return; 1840 printf("Component %d: %s\n", comp->index, comp->gcons->provider->name); 1841 printf(" chunk_count: %u\n", comp->chunk_count); 1842 printf(" chunk_next: %u\n", comp->chunk_next); 1843 printf(" flags: %u\n", comp->flags); 1844} 1845 1846#if 0 1847/* Dump a map entry */ 1848static void 1849dump_me(struct virstor_map_entry *me, unsigned int nr) 1850{ 1851 if (g_virstor_debug < LVL_DEBUG) 1852 return; 1853 printf("VIRT. CHUNK #%d: ", nr); 1854 if ((me->flags & VIRSTOR_MAP_ALLOCATED) == 0) 1855 printf("(unallocated)\n"); 1856 else 1857 printf("allocated at provider %u, provider_chunk %u\n", 1858 me->provider_no, me->provider_chunk); 1859} 1860#endif 1861 1862/* 1863 * Dismantle bio_queue and destroy its components 1864 */ 1865static void 1866bioq_dismantle(struct bio_queue_head *bq) 1867{ 1868 struct bio *b; 1869 1870 for (b = bioq_first(bq); b != NULL; b = bioq_first(bq)) { 1871 bioq_remove(bq, b); 1872 g_destroy_bio(b); 1873 } 1874} 1875 1876/* 1877 * The function that shouldn't be called. 1878 * When this is called, the stack is already garbled because of 1879 * argument mismatch. There's nothing to do now but panic, which is 1880 * accidentally the whole purpose of this function. 1881 * Motivation: to guard from accidentally calling geom methods when 1882 * they shouldn't be called. (see g_..._taste) 1883 */ 1884static void 1885invalid_call(void) 1886{ 1887 panic("invalid_call() has just been called. Something's fishy here."); 1888} 1889 1890DECLARE_GEOM_CLASS(g_virstor_class, g_virstor); /* Let there be light */ 1891