sys/geom/mirror/g_mirror.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2004-2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <sys/param.h>
  33 #include <sys/systm.h>
  34 #include <sys/fail.h>
  35 #include <sys/kernel.h>
  36 #include <sys/module.h>
  37 #include <sys/limits.h>
  38 #include <sys/lock.h>
  39 #include <sys/mutex.h>
  40 #include <sys/bio.h>
  41 #include <sys/sbuf.h>
  42 #include <sys/sysctl.h>
  43 #include <sys/malloc.h>
  44 #include <sys/eventhandler.h>
  45 #include <vm/uma.h>
  46 #include <geom/geom.h>
  47 #include <sys/proc.h>
  48 #include <sys/kthread.h>
  49 #include <sys/sched.h>
  50 #include <geom/mirror/g_mirror.h>
  51
  52 FEATURE(geom_mirror, "GEOM mirroring support");
  53
  54 static MALLOC_DEFINE(M_MIRROR, "mirror_data", "GEOM_MIRROR Data");
  55
  56 SYSCTL_DECL(_kern_geom);
  57 static SYSCTL_NODE(_kern_geom, OID_AUTO, mirror, CTLFLAG_RW, 0,
  58     "GEOM_MIRROR stuff");
  59 int g_mirror_debug = 0;
  60 SYSCTL_INT(_kern_geom_mirror, OID_AUTO, debug, CTLFLAG_RWTUN, &g_mirror_debug, 0,
  61     "Debug level");
  62 static u_int g_mirror_timeout = 4;
  63 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, timeout, CTLFLAG_RWTUN, &g_mirror_timeout,
  64     0, "Time to wait on all mirror components");
  65 static u_int g_mirror_idletime = 5;
  66 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, idletime, CTLFLAG_RWTUN,
  67     &g_mirror_idletime, 0, "Mark components as clean when idling");
  68 static u_int g_mirror_disconnect_on_failure = 1;
  69 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, disconnect_on_failure, CTLFLAG_RWTUN,
  70     &g_mirror_disconnect_on_failure, 0, "Disconnect component on I/O failure.");
  71 static u_int g_mirror_syncreqs = 2;
  72 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, sync_requests, CTLFLAG_RDTUN,
  73     &g_mirror_syncreqs, 0, "Parallel synchronization I/O requests.");
  74 static u_int g_mirror_sync_period = 5;
  75 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, sync_update_period, CTLFLAG_RWTUN,
  76     &g_mirror_sync_period, 0,
  77     "Metadata update period during synchronization, in seconds");
  78
  79 #define MSLEEP(ident, mtx, priority, wmesg, timeout)    do {            \
  80         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, (ident));       \
  81         msleep((ident), (mtx), (priority), (wmesg), (timeout));         \
  82         G_MIRROR_DEBUG(4, "%s: Woken up %p.", __func__, (ident));       \
  83 } while (0)
  84
  85 static eventhandler_tag g_mirror_post_sync = NULL;
  86 static int g_mirror_shutdown = 0;
  87
  88 static g_ctl_destroy_geom_t g_mirror_destroy_geom;
  89 static g_taste_t g_mirror_taste;
  90 static g_init_t g_mirror_init;
  91 static g_fini_t g_mirror_fini;
  92 static g_provgone_t g_mirror_providergone;
  93 static g_resize_t g_mirror_resize;
  94
  95 struct g_class g_mirror_class = {
  96         .name = G_MIRROR_CLASS_NAME,
  97         .version = G_VERSION,
  98         .ctlreq = g_mirror_config,
  99         .taste = g_mirror_taste,
 100         .destroy_geom = g_mirror_destroy_geom,
 101         .init = g_mirror_init,
 102         .fini = g_mirror_fini,
 103         .providergone = g_mirror_providergone,
 104         .resize = g_mirror_resize
 105 };
 106
 107
 108 static void g_mirror_destroy_provider(struct g_mirror_softc *sc);
 109 static int g_mirror_update_disk(struct g_mirror_disk *disk, u_int state);
 110 static void g_mirror_update_device(struct g_mirror_softc *sc, bool force);
 111 static void g_mirror_dumpconf(struct sbuf *sb, const char *indent,
 112     struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp);
 113 static void g_mirror_sync_stop(struct g_mirror_disk *disk, int type);
 114 static void g_mirror_register_request(struct bio *bp);
 115 static void g_mirror_sync_release(struct g_mirror_softc *sc);
 116
 117
 118 static const char *
 119 g_mirror_disk_state2str(int state)
 120 {
 121
 122         switch (state) {
 123         case G_MIRROR_DISK_STATE_NONE:
 124                 return ("NONE");
 125         case G_MIRROR_DISK_STATE_NEW:
 126                 return ("NEW");
 127         case G_MIRROR_DISK_STATE_ACTIVE:
 128                 return ("ACTIVE");
 129         case G_MIRROR_DISK_STATE_STALE:
 130                 return ("STALE");
 131         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
 132                 return ("SYNCHRONIZING");
 133         case G_MIRROR_DISK_STATE_DISCONNECTED:
 134                 return ("DISCONNECTED");
 135         case G_MIRROR_DISK_STATE_DESTROY:
 136                 return ("DESTROY");
 137         default:
 138                 return ("INVALID");
 139         }
 140 }
 141
 142 static const char *
 143 g_mirror_device_state2str(int state)
 144 {
 145
 146         switch (state) {
 147         case G_MIRROR_DEVICE_STATE_STARTING:
 148                 return ("STARTING");
 149         case G_MIRROR_DEVICE_STATE_RUNNING:
 150                 return ("RUNNING");
 151         default:
 152                 return ("INVALID");
 153         }
 154 }
 155
 156 static const char *
 157 g_mirror_get_diskname(struct g_mirror_disk *disk)
 158 {
 159
 160         if (disk->d_consumer == NULL || disk->d_consumer->provider == NULL)
 161                 return ("[unknown]");
 162         return (disk->d_name);
 163 }
 164
 165 /*
 166  * --- Events handling functions ---
 167  * Events in geom_mirror are used to maintain disks and device status
 168  * from one thread to simplify locking.
 169  */
 170 static void
 171 g_mirror_event_free(struct g_mirror_event *ep)
 172 {
 173
 174         free(ep, M_MIRROR);
 175 }
 176
 177 int
 178 g_mirror_event_send(void *arg, int state, int flags)
 179 {
 180         struct g_mirror_softc *sc;
 181         struct g_mirror_disk *disk;
 182         struct g_mirror_event *ep;
 183         int error;
 184
 185         ep = malloc(sizeof(*ep), M_MIRROR, M_WAITOK);
 186         G_MIRROR_DEBUG(4, "%s: Sending event %p.", __func__, ep);
 187         if ((flags & G_MIRROR_EVENT_DEVICE) != 0) {
 188                 disk = NULL;
 189                 sc = arg;
 190         } else {
 191                 disk = arg;
 192                 sc = disk->d_softc;
 193         }
 194         ep->e_disk = disk;
 195         ep->e_state = state;
 196         ep->e_flags = flags;
 197         ep->e_error = 0;
 198         mtx_lock(&sc->sc_events_mtx);
 199         TAILQ_INSERT_TAIL(&sc->sc_events, ep, e_next);
 200         mtx_unlock(&sc->sc_events_mtx);
 201         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
 202         mtx_lock(&sc->sc_queue_mtx);
 203         wakeup(sc);
 204         mtx_unlock(&sc->sc_queue_mtx);
 205         if ((flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 206                 return (0);
 207         sx_assert(&sc->sc_lock, SX_XLOCKED);
 208         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, ep);
 209         sx_xunlock(&sc->sc_lock);
 210         while ((ep->e_flags & G_MIRROR_EVENT_DONE) == 0) {
 211                 mtx_lock(&sc->sc_events_mtx);
 212                 MSLEEP(ep, &sc->sc_events_mtx, PRIBIO | PDROP, "m:event",
 213                     hz * 5);
 214         }
 215         error = ep->e_error;
 216         g_mirror_event_free(ep);
 217         sx_xlock(&sc->sc_lock);
 218         return (error);
 219 }
 220
 221 static struct g_mirror_event *
 222 g_mirror_event_first(struct g_mirror_softc *sc)
 223 {
 224         struct g_mirror_event *ep;
 225
 226         mtx_lock(&sc->sc_events_mtx);
 227         ep = TAILQ_FIRST(&sc->sc_events);
 228         mtx_unlock(&sc->sc_events_mtx);
 229         return (ep);
 230 }
 231
 232 static void
 233 g_mirror_event_remove(struct g_mirror_softc *sc, struct g_mirror_event *ep)
 234 {
 235
 236         mtx_lock(&sc->sc_events_mtx);
 237         TAILQ_REMOVE(&sc->sc_events, ep, e_next);
 238         mtx_unlock(&sc->sc_events_mtx);
 239 }
 240
 241 static void
 242 g_mirror_event_cancel(struct g_mirror_disk *disk)
 243 {
 244         struct g_mirror_softc *sc;
 245         struct g_mirror_event *ep, *tmpep;
 246
 247         sc = disk->d_softc;
 248         sx_assert(&sc->sc_lock, SX_XLOCKED);
 249
 250         mtx_lock(&sc->sc_events_mtx);
 251         TAILQ_FOREACH_SAFE(ep, &sc->sc_events, e_next, tmpep) {
 252                 if ((ep->e_flags & G_MIRROR_EVENT_DEVICE) != 0)
 253                         continue;
 254                 if (ep->e_disk != disk)
 255                         continue;
 256                 TAILQ_REMOVE(&sc->sc_events, ep, e_next);
 257                 if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 258                         g_mirror_event_free(ep);
 259                 else {
 260                         ep->e_error = ECANCELED;
 261                         wakeup(ep);
 262                 }
 263         }
 264         mtx_unlock(&sc->sc_events_mtx);
 265 }
 266
 267 /*
 268  * Return the number of disks in given state.
 269  * If state is equal to -1, count all connected disks.
 270  */
 271 u_int
 272 g_mirror_ndisks(struct g_mirror_softc *sc, int state)
 273 {
 274         struct g_mirror_disk *disk;
 275         u_int n = 0;
 276
 277         sx_assert(&sc->sc_lock, SX_LOCKED);
 278
 279         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 280                 if (state == -1 || disk->d_state == state)
 281                         n++;
 282         }
 283         return (n);
 284 }
 285
 286 /*
 287  * Find a disk in mirror by its disk ID.
 288  */
 289 static struct g_mirror_disk *
 290 g_mirror_id2disk(struct g_mirror_softc *sc, uint32_t id)
 291 {
 292         struct g_mirror_disk *disk;
 293
 294         sx_assert(&sc->sc_lock, SX_XLOCKED);
 295
 296         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 297                 if (disk->d_id == id)
 298                         return (disk);
 299         }
 300         return (NULL);
 301 }
 302
 303 static u_int
 304 g_mirror_nrequests(struct g_mirror_softc *sc, struct g_consumer *cp)
 305 {
 306         struct bio *bp;
 307         u_int nreqs = 0;
 308
 309         mtx_lock(&sc->sc_queue_mtx);
 310         TAILQ_FOREACH(bp, &sc->sc_queue.queue, bio_queue) {
 311                 if (bp->bio_from == cp)
 312                         nreqs++;
 313         }
 314         mtx_unlock(&sc->sc_queue_mtx);
 315         return (nreqs);
 316 }
 317
 318 static int
 319 g_mirror_is_busy(struct g_mirror_softc *sc, struct g_consumer *cp)
 320 {
 321
 322         if (cp->index > 0) {
 323                 G_MIRROR_DEBUG(2,
 324                     "I/O requests for %s exist, can't destroy it now.",
 325                     cp->provider->name);
 326                 return (1);
 327         }
 328         if (g_mirror_nrequests(sc, cp) > 0) {
 329                 G_MIRROR_DEBUG(2,
 330                     "I/O requests for %s in queue, can't destroy it now.",
 331                     cp->provider->name);
 332                 return (1);
 333         }
 334         return (0);
 335 }
 336
 337 static void
 338 g_mirror_destroy_consumer(void *arg, int flags __unused)
 339 {
 340         struct g_consumer *cp;
 341
 342         g_topology_assert();
 343
 344         cp = arg;
 345         G_MIRROR_DEBUG(1, "Consumer %s destroyed.", cp->provider->name);
 346         g_detach(cp);
 347         g_destroy_consumer(cp);
 348 }
 349
 350 static void
 351 g_mirror_kill_consumer(struct g_mirror_softc *sc, struct g_consumer *cp)
 352 {
 353         struct g_provider *pp;
 354         int retaste_wait;
 355
 356         g_topology_assert();
 357
 358         cp->private = NULL;
 359         if (g_mirror_is_busy(sc, cp))
 360                 return;
 361         pp = cp->provider;
 362         retaste_wait = 0;
 363         if (cp->acw == 1) {
 364                 if ((pp->geom->flags & G_GEOM_WITHER) == 0)
 365                         retaste_wait = 1;
 366         }
 367         G_MIRROR_DEBUG(2, "Access %s r%dw%de%d = %d", pp->name, -cp->acr,
 368             -cp->acw, -cp->ace, 0);
 369         if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
 370                 g_access(cp, -cp->acr, -cp->acw, -cp->ace);
 371         if (retaste_wait) {
 372                 /*
 373                  * After retaste event was send (inside g_access()), we can send
 374                  * event to detach and destroy consumer.
 375                  * A class, which has consumer to the given provider connected
 376                  * will not receive retaste event for the provider.
 377                  * This is the way how I ignore retaste events when I close
 378                  * consumers opened for write: I detach and destroy consumer
 379                  * after retaste event is sent.
 380                  */
 381                 g_post_event(g_mirror_destroy_consumer, cp, M_WAITOK, NULL);
 382                 return;
 383         }
 384         G_MIRROR_DEBUG(1, "Consumer %s destroyed.", pp->name);
 385         g_detach(cp);
 386         g_destroy_consumer(cp);
 387 }
 388
 389 static int
 390 g_mirror_connect_disk(struct g_mirror_disk *disk, struct g_provider *pp)
 391 {
 392         struct g_consumer *cp;
 393         int error;
 394
 395         g_topology_assert_not();
 396         KASSERT(disk->d_consumer == NULL,
 397             ("Disk already connected (device %s).", disk->d_softc->sc_name));
 398
 399         g_topology_lock();
 400         cp = g_new_consumer(disk->d_softc->sc_geom);
 401         cp->flags |= G_CF_DIRECT_RECEIVE;
 402         error = g_attach(cp, pp);
 403         if (error != 0) {
 404                 g_destroy_consumer(cp);
 405                 g_topology_unlock();
 406                 return (error);
 407         }
 408         error = g_access(cp, 1, 1, 1);
 409         if (error != 0) {
 410                 g_detach(cp);
 411                 g_destroy_consumer(cp);
 412                 g_topology_unlock();
 413                 G_MIRROR_DEBUG(0, "Cannot open consumer %s (error=%d).",
 414                     pp->name, error);
 415                 return (error);
 416         }
 417         g_topology_unlock();
 418         disk->d_consumer = cp;
 419         disk->d_consumer->private = disk;
 420         disk->d_consumer->index = 0;
 421
 422         G_MIRROR_DEBUG(2, "Disk %s connected.", g_mirror_get_diskname(disk));
 423         return (0);
 424 }
 425
 426 static void
 427 g_mirror_disconnect_consumer(struct g_mirror_softc *sc, struct g_consumer *cp)
 428 {
 429
 430         g_topology_assert();
 431
 432         if (cp == NULL)
 433                 return;
 434         if (cp->provider != NULL)
 435                 g_mirror_kill_consumer(sc, cp);
 436         else
 437                 g_destroy_consumer(cp);
 438 }
 439
 440 /*
 441  * Initialize disk. This means allocate memory, create consumer, attach it
 442  * to the provider and open access (r1w1e1) to it.
 443  */
 444 static struct g_mirror_disk *
 445 g_mirror_init_disk(struct g_mirror_softc *sc, struct g_provider *pp,
 446     struct g_mirror_metadata *md, int *errorp)
 447 {
 448         struct g_mirror_disk *disk;
 449         int i, error;
 450
 451         disk = malloc(sizeof(*disk), M_MIRROR, M_NOWAIT | M_ZERO);
 452         if (disk == NULL) {
 453                 error = ENOMEM;
 454                 goto fail;
 455         }
 456         disk->d_softc = sc;
 457         error = g_mirror_connect_disk(disk, pp);
 458         if (error != 0)
 459                 goto fail;
 460         disk->d_id = md->md_did;
 461         disk->d_state = G_MIRROR_DISK_STATE_NONE;
 462         disk->d_priority = md->md_priority;
 463         disk->d_flags = md->md_dflags;
 464         error = g_getattr("GEOM::candelete", disk->d_consumer, &i);
 465         if (error == 0 && i != 0)
 466                 disk->d_flags |= G_MIRROR_DISK_FLAG_CANDELETE;
 467         if (md->md_provider[0] != '\0')
 468                 disk->d_flags |= G_MIRROR_DISK_FLAG_HARDCODED;
 469         disk->d_sync.ds_consumer = NULL;
 470         disk->d_sync.ds_offset = md->md_sync_offset;
 471         disk->d_sync.ds_offset_done = md->md_sync_offset;
 472         disk->d_sync.ds_update_ts = time_uptime;
 473         disk->d_genid = md->md_genid;
 474         disk->d_sync.ds_syncid = md->md_syncid;
 475         if (errorp != NULL)
 476                 *errorp = 0;
 477         return (disk);
 478 fail:
 479         if (errorp != NULL)
 480                 *errorp = error;
 481         if (disk != NULL)
 482                 free(disk, M_MIRROR);
 483         return (NULL);
 484 }
 485
 486 static void
 487 g_mirror_destroy_disk(struct g_mirror_disk *disk)
 488 {
 489         struct g_mirror_softc *sc;
 490
 491         g_topology_assert_not();
 492         sc = disk->d_softc;
 493         sx_assert(&sc->sc_lock, SX_XLOCKED);
 494
 495         LIST_REMOVE(disk, d_next);
 496         g_mirror_event_cancel(disk);
 497         if (sc->sc_hint == disk)
 498                 sc->sc_hint = NULL;
 499         switch (disk->d_state) {
 500         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
 501                 g_mirror_sync_stop(disk, 1);
 502                 /* FALLTHROUGH */
 503         case G_MIRROR_DISK_STATE_NEW:
 504         case G_MIRROR_DISK_STATE_STALE:
 505         case G_MIRROR_DISK_STATE_ACTIVE:
 506                 g_topology_lock();
 507                 g_mirror_disconnect_consumer(sc, disk->d_consumer);
 508                 g_topology_unlock();
 509                 free(disk, M_MIRROR);
 510                 break;
 511         default:
 512                 KASSERT(0 == 1, ("Wrong disk state (%s, %s).",
 513                     g_mirror_get_diskname(disk),
 514                     g_mirror_disk_state2str(disk->d_state)));
 515         }
 516 }
 517
 518 static void
 519 g_mirror_free_device(struct g_mirror_softc *sc)
 520 {
 521
 522         mtx_destroy(&sc->sc_queue_mtx);
 523         mtx_destroy(&sc->sc_events_mtx);
 524         mtx_destroy(&sc->sc_done_mtx);
 525         sx_destroy(&sc->sc_lock);
 526         free(sc, M_MIRROR);
 527 }
 528
 529 static void
 530 g_mirror_providergone(struct g_provider *pp)
 531 {
 532         struct g_mirror_softc *sc = pp->private;
 533
 534         if ((--sc->sc_refcnt) == 0)
 535                 g_mirror_free_device(sc);
 536 }
 537
 538 static void
 539 g_mirror_destroy_device(struct g_mirror_softc *sc)
 540 {
 541         struct g_mirror_disk *disk;
 542         struct g_mirror_event *ep;
 543         struct g_geom *gp;
 544         struct g_consumer *cp, *tmpcp;
 545
 546         g_topology_assert_not();
 547         sx_assert(&sc->sc_lock, SX_XLOCKED);
 548
 549         gp = sc->sc_geom;
 550         if (sc->sc_provider != NULL)
 551                 g_mirror_destroy_provider(sc);
 552         for (disk = LIST_FIRST(&sc->sc_disks); disk != NULL;
 553             disk = LIST_FIRST(&sc->sc_disks)) {
 554                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
 555                 g_mirror_update_metadata(disk);
 556                 g_mirror_destroy_disk(disk);
 557         }
 558         while ((ep = g_mirror_event_first(sc)) != NULL) {
 559                 g_mirror_event_remove(sc, ep);
 560                 if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 561                         g_mirror_event_free(ep);
 562                 else {
 563                         ep->e_error = ECANCELED;
 564                         ep->e_flags |= G_MIRROR_EVENT_DONE;
 565                         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, ep);
 566                         mtx_lock(&sc->sc_events_mtx);
 567                         wakeup(ep);
 568                         mtx_unlock(&sc->sc_events_mtx);
 569                 }
 570         }
 571         callout_drain(&sc->sc_callout);
 572
 573         g_topology_lock();
 574         LIST_FOREACH_SAFE(cp, &sc->sc_sync.ds_geom->consumer, consumer, tmpcp) {
 575                 g_mirror_disconnect_consumer(sc, cp);
 576         }
 577         g_wither_geom(sc->sc_sync.ds_geom, ENXIO);
 578         G_MIRROR_DEBUG(0, "Device %s destroyed.", gp->name);
 579         g_wither_geom(gp, ENXIO);
 580         sx_xunlock(&sc->sc_lock);
 581         if ((--sc->sc_refcnt) == 0)
 582                 g_mirror_free_device(sc);
 583         g_topology_unlock();
 584 }
 585
 586 static void
 587 g_mirror_orphan(struct g_consumer *cp)
 588 {
 589         struct g_mirror_disk *disk;
 590
 591         g_topology_assert();
 592
 593         disk = cp->private;
 594         if (disk == NULL)
 595                 return;
 596         disk->d_softc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
 597         g_mirror_event_send(disk, G_MIRROR_DISK_STATE_DISCONNECTED,
 598             G_MIRROR_EVENT_DONTWAIT);
 599 }
 600
 601 /*
 602  * Function should return the next active disk on the list.
 603  * It is possible that it will be the same disk as given.
 604  * If there are no active disks on list, NULL is returned.
 605  */
 606 static __inline struct g_mirror_disk *
 607 g_mirror_find_next(struct g_mirror_softc *sc, struct g_mirror_disk *disk)
 608 {
 609         struct g_mirror_disk *dp;
 610
 611         for (dp = LIST_NEXT(disk, d_next); dp != disk;
 612             dp = LIST_NEXT(dp, d_next)) {
 613                 if (dp == NULL)
 614                         dp = LIST_FIRST(&sc->sc_disks);
 615                 if (dp->d_state == G_MIRROR_DISK_STATE_ACTIVE)
 616                         break;
 617         }
 618         if (dp->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 619                 return (NULL);
 620         return (dp);
 621 }
 622
 623 static struct g_mirror_disk *
 624 g_mirror_get_disk(struct g_mirror_softc *sc)
 625 {
 626         struct g_mirror_disk *disk;
 627
 628         if (sc->sc_hint == NULL) {
 629                 sc->sc_hint = LIST_FIRST(&sc->sc_disks);
 630                 if (sc->sc_hint == NULL)
 631                         return (NULL);
 632         }
 633         disk = sc->sc_hint;
 634         if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE) {
 635                 disk = g_mirror_find_next(sc, disk);
 636                 if (disk == NULL)
 637                         return (NULL);
 638         }
 639         sc->sc_hint = g_mirror_find_next(sc, disk);
 640         return (disk);
 641 }
 642
 643 static int
 644 g_mirror_write_metadata(struct g_mirror_disk *disk,
 645     struct g_mirror_metadata *md)
 646 {
 647         struct g_mirror_softc *sc;
 648         struct g_consumer *cp;
 649         off_t offset, length;
 650         u_char *sector;
 651         int error = 0;
 652
 653         g_topology_assert_not();
 654         sc = disk->d_softc;
 655         sx_assert(&sc->sc_lock, SX_LOCKED);
 656
 657         cp = disk->d_consumer;
 658         KASSERT(cp != NULL, ("NULL consumer (%s).", sc->sc_name));
 659         KASSERT(cp->provider != NULL, ("NULL provider (%s).", sc->sc_name));
 660         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
 661             ("Consumer %s closed? (r%dw%de%d).", cp->provider->name, cp->acr,
 662             cp->acw, cp->ace));
 663         length = cp->provider->sectorsize;
 664         offset = cp->provider->mediasize - length;
 665         sector = malloc((size_t)length, M_MIRROR, M_WAITOK | M_ZERO);
 666         if (md != NULL &&
 667             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_WIPE) == 0) {
 668                 /*
 669                  * Handle the case, when the size of parent provider reduced.
 670                  */
 671                 if (offset < md->md_mediasize)
 672                         error = ENOSPC;
 673                 else
 674                         mirror_metadata_encode(md, sector);
 675         }
 676         KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_metadata_write, error);
 677         if (error == 0)
 678                 error = g_write_data(cp, offset, sector, length);
 679         free(sector, M_MIRROR);
 680         if (error != 0) {
 681                 if ((disk->d_flags & G_MIRROR_DISK_FLAG_BROKEN) == 0) {
 682                         disk->d_flags |= G_MIRROR_DISK_FLAG_BROKEN;
 683                         G_MIRROR_DEBUG(0, "Cannot write metadata on %s "
 684                             "(device=%s, error=%d).",
 685                             g_mirror_get_diskname(disk), sc->sc_name, error);
 686                 } else {
 687                         G_MIRROR_DEBUG(1, "Cannot write metadata on %s "
 688                             "(device=%s, error=%d).",
 689                             g_mirror_get_diskname(disk), sc->sc_name, error);
 690                 }
 691                 if (g_mirror_disconnect_on_failure &&
 692                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 1) {
 693                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
 694                         g_mirror_event_send(disk,
 695                             G_MIRROR_DISK_STATE_DISCONNECTED,
 696                             G_MIRROR_EVENT_DONTWAIT);
 697                 }
 698         }
 699         return (error);
 700 }
 701
 702 static int
 703 g_mirror_clear_metadata(struct g_mirror_disk *disk)
 704 {
 705         int error;
 706
 707         g_topology_assert_not();
 708         sx_assert(&disk->d_softc->sc_lock, SX_LOCKED);
 709
 710         if (disk->d_softc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
 711                 return (0);
 712         error = g_mirror_write_metadata(disk, NULL);
 713         if (error == 0) {
 714                 G_MIRROR_DEBUG(2, "Metadata on %s cleared.",
 715                     g_mirror_get_diskname(disk));
 716         } else {
 717                 G_MIRROR_DEBUG(0,
 718                     "Cannot clear metadata on disk %s (error=%d).",
 719                     g_mirror_get_diskname(disk), error);
 720         }
 721         return (error);
 722 }
 723
 724 void
 725 g_mirror_fill_metadata(struct g_mirror_softc *sc, struct g_mirror_disk *disk,
 726     struct g_mirror_metadata *md)
 727 {
 728
 729         strlcpy(md->md_magic, G_MIRROR_MAGIC, sizeof(md->md_magic));
 730         md->md_version = G_MIRROR_VERSION;
 731         strlcpy(md->md_name, sc->sc_name, sizeof(md->md_name));
 732         md->md_mid = sc->sc_id;
 733         md->md_all = sc->sc_ndisks;
 734         md->md_slice = sc->sc_slice;
 735         md->md_balance = sc->sc_balance;
 736         md->md_genid = sc->sc_genid;
 737         md->md_mediasize = sc->sc_mediasize;
 738         md->md_sectorsize = sc->sc_sectorsize;
 739         md->md_mflags = (sc->sc_flags & G_MIRROR_DEVICE_FLAG_MASK);
 740         bzero(md->md_provider, sizeof(md->md_provider));
 741         if (disk == NULL) {
 742                 md->md_did = arc4random();
 743                 md->md_priority = 0;
 744                 md->md_syncid = 0;
 745                 md->md_dflags = 0;
 746                 md->md_sync_offset = 0;
 747                 md->md_provsize = 0;
 748         } else {
 749                 md->md_did = disk->d_id;
 750                 md->md_priority = disk->d_priority;
 751                 md->md_syncid = disk->d_sync.ds_syncid;
 752                 md->md_dflags = (disk->d_flags & G_MIRROR_DISK_FLAG_MASK);
 753                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
 754                         md->md_sync_offset = disk->d_sync.ds_offset_done;
 755                 else
 756                         md->md_sync_offset = 0;
 757                 if ((disk->d_flags & G_MIRROR_DISK_FLAG_HARDCODED) != 0) {
 758                         strlcpy(md->md_provider,
 759                             disk->d_consumer->provider->name,
 760                             sizeof(md->md_provider));
 761                 }
 762                 md->md_provsize = disk->d_consumer->provider->mediasize;
 763         }
 764 }
 765
 766 void
 767 g_mirror_update_metadata(struct g_mirror_disk *disk)
 768 {
 769         struct g_mirror_softc *sc;
 770         struct g_mirror_metadata md;
 771         int error;
 772
 773         g_topology_assert_not();
 774         sc = disk->d_softc;
 775         sx_assert(&sc->sc_lock, SX_LOCKED);
 776
 777         if (sc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
 778                 return;
 779         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_WIPE) == 0)
 780                 g_mirror_fill_metadata(sc, disk, &md);
 781         error = g_mirror_write_metadata(disk, &md);
 782         if (error == 0) {
 783                 G_MIRROR_DEBUG(2, "Metadata on %s updated.",
 784                     g_mirror_get_diskname(disk));
 785         } else {
 786                 G_MIRROR_DEBUG(0,
 787                     "Cannot update metadata on disk %s (error=%d).",
 788                     g_mirror_get_diskname(disk), error);
 789         }
 790 }
 791
 792 static void
 793 g_mirror_bump_syncid(struct g_mirror_softc *sc)
 794 {
 795         struct g_mirror_disk *disk;
 796
 797         g_topology_assert_not();
 798         sx_assert(&sc->sc_lock, SX_XLOCKED);
 799         KASSERT(g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 0,
 800             ("%s called with no active disks (device=%s).", __func__,
 801             sc->sc_name));
 802
 803         sc->sc_syncid++;
 804         G_MIRROR_DEBUG(1, "Device %s: syncid bumped to %u.", sc->sc_name,
 805             sc->sc_syncid);
 806         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 807                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
 808                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
 809                         disk->d_sync.ds_syncid = sc->sc_syncid;
 810                         g_mirror_update_metadata(disk);
 811                 }
 812         }
 813 }
 814
 815 static void
 816 g_mirror_bump_genid(struct g_mirror_softc *sc)
 817 {
 818         struct g_mirror_disk *disk;
 819
 820         g_topology_assert_not();
 821         sx_assert(&sc->sc_lock, SX_XLOCKED);
 822         KASSERT(g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 0,
 823             ("%s called with no active disks (device=%s).", __func__,
 824             sc->sc_name));
 825
 826         sc->sc_genid++;
 827         G_MIRROR_DEBUG(1, "Device %s: genid bumped to %u.", sc->sc_name,
 828             sc->sc_genid);
 829         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 830                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
 831                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
 832                         disk->d_genid = sc->sc_genid;
 833                         g_mirror_update_metadata(disk);
 834                 }
 835         }
 836 }
 837
 838 static int
 839 g_mirror_idle(struct g_mirror_softc *sc, int acw)
 840 {
 841         struct g_mirror_disk *disk;
 842         int timeout;
 843
 844         g_topology_assert_not();
 845         sx_assert(&sc->sc_lock, SX_XLOCKED);
 846
 847         if (sc->sc_provider == NULL)
 848                 return (0);
 849         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
 850                 return (0);
 851         if (sc->sc_idle)
 852                 return (0);
 853         if (sc->sc_writes > 0)
 854                 return (0);
 855         if (acw > 0 || (acw == -1 && sc->sc_provider->acw > 0)) {
 856                 timeout = g_mirror_idletime - (time_uptime - sc->sc_last_write);
 857                 if (!g_mirror_shutdown && timeout > 0)
 858                         return (timeout);
 859         }
 860         sc->sc_idle = 1;
 861         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 862                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 863                         continue;
 864                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as clean.",
 865                     g_mirror_get_diskname(disk), sc->sc_name);
 866                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
 867                 g_mirror_update_metadata(disk);
 868         }
 869         return (0);
 870 }
 871
 872 static void
 873 g_mirror_unidle(struct g_mirror_softc *sc)
 874 {
 875         struct g_mirror_disk *disk;
 876
 877         g_topology_assert_not();
 878         sx_assert(&sc->sc_lock, SX_XLOCKED);
 879
 880         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
 881                 return;
 882         sc->sc_idle = 0;
 883         sc->sc_last_write = time_uptime;
 884         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 885                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 886                         continue;
 887                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as dirty.",
 888                     g_mirror_get_diskname(disk), sc->sc_name);
 889                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
 890                 g_mirror_update_metadata(disk);
 891         }
 892 }
 893
 894 static void
 895 g_mirror_flush_done(struct bio *bp)
 896 {
 897         struct g_mirror_softc *sc;
 898         struct bio *pbp;
 899
 900         pbp = bp->bio_parent;
 901         sc = pbp->bio_to->private;
 902         mtx_lock(&sc->sc_done_mtx);
 903         if (pbp->bio_error == 0)
 904                 pbp->bio_error = bp->bio_error;
 905         pbp->bio_completed += bp->bio_completed;
 906         pbp->bio_inbed++;
 907         if (pbp->bio_children == pbp->bio_inbed) {
 908                 mtx_unlock(&sc->sc_done_mtx);
 909                 g_io_deliver(pbp, pbp->bio_error);
 910         } else
 911                 mtx_unlock(&sc->sc_done_mtx);
 912         g_destroy_bio(bp);
 913 }
 914
 915 static void
 916 g_mirror_done(struct bio *bp)
 917 {
 918         struct g_mirror_softc *sc;
 919
 920         sc = bp->bio_from->geom->softc;
 921         bp->bio_cflags = G_MIRROR_BIO_FLAG_REGULAR;
 922         mtx_lock(&sc->sc_queue_mtx);
 923         bioq_insert_tail(&sc->sc_queue, bp);
 924         mtx_unlock(&sc->sc_queue_mtx);
 925         wakeup(sc);
 926 }
 927
 928 static void
 929 g_mirror_regular_request(struct bio *bp)
 930 {
 931         struct g_mirror_softc *sc;
 932         struct g_mirror_disk *disk;
 933         struct bio *pbp;
 934
 935         g_topology_assert_not();
 936
 937         pbp = bp->bio_parent;
 938         sc = pbp->bio_to->private;
 939         bp->bio_from->index--;
 940         if (bp->bio_cmd == BIO_WRITE || bp->bio_cmd == BIO_DELETE)
 941                 sc->sc_writes--;
 942         disk = bp->bio_from->private;
 943         if (disk == NULL) {
 944                 g_topology_lock();
 945                 g_mirror_kill_consumer(sc, bp->bio_from);
 946                 g_topology_unlock();
 947         }
 948
 949         if (bp->bio_cmd == BIO_READ)
 950                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_read,
 951                     bp->bio_error);
 952         else if (bp->bio_cmd == BIO_WRITE)
 953                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_write,
 954                     bp->bio_error);
 955
 956         pbp->bio_inbed++;
 957         KASSERT(pbp->bio_inbed <= pbp->bio_children,
 958             ("bio_inbed (%u) is bigger than bio_children (%u).", pbp->bio_inbed,
 959             pbp->bio_children));
 960         if (bp->bio_error == 0 && pbp->bio_error == 0) {
 961                 G_MIRROR_LOGREQ(3, bp, "Request delivered.");
 962                 g_destroy_bio(bp);
 963                 if (pbp->bio_children == pbp->bio_inbed) {
 964                         G_MIRROR_LOGREQ(3, pbp, "Request delivered.");
 965                         pbp->bio_completed = pbp->bio_length;
 966                         if (pbp->bio_cmd == BIO_WRITE ||
 967                             pbp->bio_cmd == BIO_DELETE) {
 968                                 bioq_remove(&sc->sc_inflight, pbp);
 969                                 /* Release delayed sync requests if possible. */
 970                                 g_mirror_sync_release(sc);
 971                         }
 972                         g_io_deliver(pbp, pbp->bio_error);
 973                 }
 974                 return;
 975         } else if (bp->bio_error != 0) {
 976                 if (pbp->bio_error == 0)
 977                         pbp->bio_error = bp->bio_error;
 978                 if (disk != NULL) {
 979                         if ((disk->d_flags & G_MIRROR_DISK_FLAG_BROKEN) == 0) {
 980                                 disk->d_flags |= G_MIRROR_DISK_FLAG_BROKEN;
 981                                 G_MIRROR_LOGREQ(0, bp,
 982                                     "Request failed (error=%d).",
 983                                     bp->bio_error);
 984                         } else {
 985                                 G_MIRROR_LOGREQ(1, bp,
 986                                     "Request failed (error=%d).",
 987                                     bp->bio_error);
 988                         }
 989                         if (g_mirror_disconnect_on_failure &&
 990                             g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 1)
 991                         {
 992                                 if (bp->bio_error == ENXIO &&
 993                                     bp->bio_cmd == BIO_READ)
 994                                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
 995                                 else if (bp->bio_error == ENXIO)
 996                                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID_NOW;
 997                                 else
 998                                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
 999                                 g_mirror_event_send(disk,
1000                                     G_MIRROR_DISK_STATE_DISCONNECTED,
1001                                     G_MIRROR_EVENT_DONTWAIT);
1002                         }
1003                 }
1004                 switch (pbp->bio_cmd) {
1005                 case BIO_DELETE:
1006                 case BIO_WRITE:
1007                         pbp->bio_inbed--;
1008                         pbp->bio_children--;
1009                         break;
1010                 }
1011         }
1012         g_destroy_bio(bp);
1013
1014         switch (pbp->bio_cmd) {
1015         case BIO_READ:
1016                 if (pbp->bio_inbed < pbp->bio_children)
1017                         break;
1018                 if (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 1)
1019                         g_io_deliver(pbp, pbp->bio_error);
1020                 else {
1021                         pbp->bio_error = 0;
1022                         mtx_lock(&sc->sc_queue_mtx);
1023                         bioq_insert_tail(&sc->sc_queue, pbp);
1024                         mtx_unlock(&sc->sc_queue_mtx);
1025                         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
1026                         wakeup(sc);
1027                 }
1028                 break;
1029         case BIO_DELETE:
1030         case BIO_WRITE:
1031                 if (pbp->bio_children == 0) {
1032                         /*
1033                          * All requests failed.
1034                          */
1035                 } else if (pbp->bio_inbed < pbp->bio_children) {
1036                         /* Do nothing. */
1037                         break;
1038                 } else if (pbp->bio_children == pbp->bio_inbed) {
1039                         /* Some requests succeeded. */
1040                         pbp->bio_error = 0;
1041                         pbp->bio_completed = pbp->bio_length;
1042                 }
1043                 bioq_remove(&sc->sc_inflight, pbp);
1044                 /* Release delayed sync requests if possible. */
1045                 g_mirror_sync_release(sc);
1046                 g_io_deliver(pbp, pbp->bio_error);
1047                 break;
1048         default:
1049                 KASSERT(1 == 0, ("Invalid request: %u.", pbp->bio_cmd));
1050                 break;
1051         }
1052 }
1053
1054 static void
1055 g_mirror_sync_done(struct bio *bp)
1056 {
1057         struct g_mirror_softc *sc;
1058
1059         G_MIRROR_LOGREQ(3, bp, "Synchronization request delivered.");
1060         sc = bp->bio_from->geom->softc;
1061         bp->bio_cflags = G_MIRROR_BIO_FLAG_SYNC;
1062         mtx_lock(&sc->sc_queue_mtx);
1063         bioq_insert_tail(&sc->sc_queue, bp);
1064         mtx_unlock(&sc->sc_queue_mtx);
1065         wakeup(sc);
1066 }
1067
1068 static void
1069 g_mirror_candelete(struct bio *bp)
1070 {
1071         struct g_mirror_softc *sc;
1072         struct g_mirror_disk *disk;
1073         int *val;
1074
1075         sc = bp->bio_to->private;
1076         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1077                 if (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE)
1078                         break;
1079         }
1080         val = (int *)bp->bio_data;
1081         *val = (disk != NULL);
1082         g_io_deliver(bp, 0);
1083 }
1084
1085 static void
1086 g_mirror_kernel_dump(struct bio *bp)
1087 {
1088         struct g_mirror_softc *sc;
1089         struct g_mirror_disk *disk;
1090         struct bio *cbp;
1091         struct g_kerneldump *gkd;
1092
1093         /*
1094          * We configure dumping to the first component, because this component
1095          * will be used for reading with 'prefer' balance algorithm.
1096          * If the component with the highest priority is currently disconnected
1097          * we will not be able to read the dump after the reboot if it will be
1098          * connected and synchronized later. Can we do something better?
1099          */
1100         sc = bp->bio_to->private;
1101         disk = LIST_FIRST(&sc->sc_disks);
1102
1103         gkd = (struct g_kerneldump *)bp->bio_data;
1104         if (gkd->length > bp->bio_to->mediasize)
1105                 gkd->length = bp->bio_to->mediasize;
1106         cbp = g_clone_bio(bp);
1107         if (cbp == NULL) {
1108                 g_io_deliver(bp, ENOMEM);
1109                 return;
1110         }
1111         cbp->bio_done = g_std_done;
1112         g_io_request(cbp, disk->d_consumer);
1113         G_MIRROR_DEBUG(1, "Kernel dump will go to %s.",
1114             g_mirror_get_diskname(disk));
1115 }
1116
1117 static void
1118 g_mirror_flush(struct g_mirror_softc *sc, struct bio *bp)
1119 {
1120         struct bio_queue_head queue;
1121         struct g_mirror_disk *disk;
1122         struct g_consumer *cp;
1123         struct bio *cbp;
1124
1125         bioq_init(&queue);
1126         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1127                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1128                         continue;
1129                 cbp = g_clone_bio(bp);
1130                 if (cbp == NULL) {
1131                         while ((cbp = bioq_takefirst(&queue)) != NULL)
1132                                 g_destroy_bio(cbp);
1133                         if (bp->bio_error == 0)
1134                                 bp->bio_error = ENOMEM;
1135                         g_io_deliver(bp, bp->bio_error);
1136                         return;
1137                 }
1138                 bioq_insert_tail(&queue, cbp);
1139                 cbp->bio_done = g_mirror_flush_done;
1140                 cbp->bio_caller1 = disk;
1141                 cbp->bio_to = disk->d_consumer->provider;
1142         }
1143         while ((cbp = bioq_takefirst(&queue)) != NULL) {
1144                 G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1145                 disk = cbp->bio_caller1;
1146                 cbp->bio_caller1 = NULL;
1147                 cp = disk->d_consumer;
1148                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1149                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1150                     cp->acr, cp->acw, cp->ace));
1151                 g_io_request(cbp, disk->d_consumer);
1152         }
1153 }
1154
1155 static void
1156 g_mirror_start(struct bio *bp)
1157 {
1158         struct g_mirror_softc *sc;
1159
1160         sc = bp->bio_to->private;
1161         /*
1162          * If sc == NULL or there are no valid disks, provider's error
1163          * should be set and g_mirror_start() should not be called at all.
1164          */
1165         KASSERT(sc != NULL && sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
1166             ("Provider's error should be set (error=%d)(mirror=%s).",
1167             bp->bio_to->error, bp->bio_to->name));
1168         G_MIRROR_LOGREQ(3, bp, "Request received.");
1169
1170         switch (bp->bio_cmd) {
1171         case BIO_READ:
1172         case BIO_WRITE:
1173         case BIO_DELETE:
1174                 break;
1175         case BIO_FLUSH:
1176                 g_mirror_flush(sc, bp);
1177                 return;
1178         case BIO_GETATTR:
1179                 if (!strcmp(bp->bio_attribute, "GEOM::candelete")) {
1180                         g_mirror_candelete(bp);
1181                         return;
1182                 } else if (strcmp("GEOM::kerneldump", bp->bio_attribute) == 0) {
1183                         g_mirror_kernel_dump(bp);
1184                         return;
1185                 }
1186                 /* FALLTHROUGH */
1187         default:
1188                 g_io_deliver(bp, EOPNOTSUPP);
1189                 return;
1190         }
1191         mtx_lock(&sc->sc_queue_mtx);
1192         if (bp->bio_to->error != 0) {
1193                 mtx_unlock(&sc->sc_queue_mtx);
1194                 g_io_deliver(bp, bp->bio_to->error);
1195                 return;
1196         }
1197         bioq_insert_tail(&sc->sc_queue, bp);
1198         mtx_unlock(&sc->sc_queue_mtx);
1199         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
1200         wakeup(sc);
1201 }
1202
1203 /*
1204  * Return TRUE if the given request is colliding with a in-progress
1205  * synchronization request.
1206  */
1207 static bool
1208 g_mirror_sync_collision(struct g_mirror_softc *sc, struct bio *bp)
1209 {
1210         struct g_mirror_disk *disk;
1211         struct bio *sbp;
1212         off_t rstart, rend, sstart, send;
1213         u_int i;
1214
1215         if (sc->sc_sync.ds_ndisks == 0)
1216                 return (false);
1217         rstart = bp->bio_offset;
1218         rend = bp->bio_offset + bp->bio_length;
1219         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1220                 if (disk->d_state != G_MIRROR_DISK_STATE_SYNCHRONIZING)
1221                         continue;
1222                 for (i = 0; i < g_mirror_syncreqs; i++) {
1223                         sbp = disk->d_sync.ds_bios[i];
1224                         if (sbp == NULL)
1225                                 continue;
1226                         sstart = sbp->bio_offset;
1227                         send = sbp->bio_offset + sbp->bio_length;
1228                         if (rend > sstart && rstart < send)
1229                                 return (true);
1230                 }
1231         }
1232         return (false);
1233 }
1234
1235 /*
1236  * Return TRUE if the given sync request is colliding with a in-progress regular
1237  * request.
1238  */
1239 static bool
1240 g_mirror_regular_collision(struct g_mirror_softc *sc, struct bio *sbp)
1241 {
1242         off_t rstart, rend, sstart, send;
1243         struct bio *bp;
1244
1245         if (sc->sc_sync.ds_ndisks == 0)
1246                 return (false);
1247         sstart = sbp->bio_offset;
1248         send = sbp->bio_offset + sbp->bio_length;
1249         TAILQ_FOREACH(bp, &sc->sc_inflight.queue, bio_queue) {
1250                 rstart = bp->bio_offset;
1251                 rend = bp->bio_offset + bp->bio_length;
1252                 if (rend > sstart && rstart < send)
1253                         return (true);
1254         }
1255         return (false);
1256 }
1257
1258 /*
1259  * Puts request onto delayed queue.
1260  */
1261 static void
1262 g_mirror_regular_delay(struct g_mirror_softc *sc, struct bio *bp)
1263 {
1264
1265         G_MIRROR_LOGREQ(2, bp, "Delaying request.");
1266         bioq_insert_head(&sc->sc_regular_delayed, bp);
1267 }
1268
1269 /*
1270  * Puts synchronization request onto delayed queue.
1271  */
1272 static void
1273 g_mirror_sync_delay(struct g_mirror_softc *sc, struct bio *bp)
1274 {
1275
1276         G_MIRROR_LOGREQ(2, bp, "Delaying synchronization request.");
1277         bioq_insert_tail(&sc->sc_sync_delayed, bp);
1278 }
1279
1280 /*
1281  * Releases delayed regular requests which don't collide anymore with sync
1282  * requests.
1283  */
1284 static void
1285 g_mirror_regular_release(struct g_mirror_softc *sc)
1286 {
1287         struct bio *bp, *bp2;
1288
1289         TAILQ_FOREACH_SAFE(bp, &sc->sc_regular_delayed.queue, bio_queue, bp2) {
1290                 if (g_mirror_sync_collision(sc, bp))
1291                         continue;
1292                 bioq_remove(&sc->sc_regular_delayed, bp);
1293                 G_MIRROR_LOGREQ(2, bp, "Releasing delayed request (%p).", bp);
1294                 mtx_lock(&sc->sc_queue_mtx);
1295                 bioq_insert_head(&sc->sc_queue, bp);
1296                 mtx_unlock(&sc->sc_queue_mtx);
1297         }
1298 }
1299
1300 /*
1301  * Releases delayed sync requests which don't collide anymore with regular
1302  * requests.
1303  */
1304 static void
1305 g_mirror_sync_release(struct g_mirror_softc *sc)
1306 {
1307         struct bio *bp, *bp2;
1308
1309         TAILQ_FOREACH_SAFE(bp, &sc->sc_sync_delayed.queue, bio_queue, bp2) {
1310                 if (g_mirror_regular_collision(sc, bp))
1311                         continue;
1312                 bioq_remove(&sc->sc_sync_delayed, bp);
1313                 G_MIRROR_LOGREQ(2, bp,
1314                     "Releasing delayed synchronization request.");
1315                 g_io_request(bp, bp->bio_from);
1316         }
1317 }
1318
1319 /*
1320  * Free a synchronization request and clear its slot in the array.
1321  */
1322 static void
1323 g_mirror_sync_request_free(struct g_mirror_disk *disk, struct bio *bp)
1324 {
1325         int idx;
1326
1327         if (disk != NULL && disk->d_sync.ds_bios != NULL) {
1328                 idx = (int)(uintptr_t)bp->bio_caller1;
1329                 KASSERT(disk->d_sync.ds_bios[idx] == bp,
1330                     ("unexpected sync BIO at %p:%d", disk, idx));
1331                 disk->d_sync.ds_bios[idx] = NULL;
1332         }
1333         free(bp->bio_data, M_MIRROR);
1334         g_destroy_bio(bp);
1335 }
1336
1337 /*
1338  * Handle synchronization requests.
1339  * Every synchronization request is two-steps process: first, READ request is
1340  * send to active provider and then WRITE request (with read data) to the provider
1341  * being synchronized. When WRITE is finished, new synchronization request is
1342  * send.
1343  */
1344 static void
1345 g_mirror_sync_request(struct bio *bp)
1346 {
1347         struct g_mirror_softc *sc;
1348         struct g_mirror_disk *disk;
1349         struct g_mirror_disk_sync *sync;
1350
1351         bp->bio_from->index--;
1352         sc = bp->bio_from->geom->softc;
1353         disk = bp->bio_from->private;
1354         if (disk == NULL) {
1355                 sx_xunlock(&sc->sc_lock); /* Avoid recursion on sc_lock. */
1356                 g_topology_lock();
1357                 g_mirror_kill_consumer(sc, bp->bio_from);
1358                 g_topology_unlock();
1359                 g_mirror_sync_request_free(NULL, bp);
1360                 sx_xlock(&sc->sc_lock);
1361                 return;
1362         }
1363
1364         /*
1365          * Synchronization request.
1366          */
1367         switch (bp->bio_cmd) {
1368         case BIO_READ:
1369             {
1370                 struct g_consumer *cp;
1371
1372                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_sync_request_read,
1373                     bp->bio_error);
1374
1375                 if (bp->bio_error != 0) {
1376                         G_MIRROR_LOGREQ(0, bp,
1377                             "Synchronization request failed (error=%d).",
1378                             bp->bio_error);
1379                         g_mirror_sync_request_free(disk, bp);
1380                         return;
1381                 }
1382                 G_MIRROR_LOGREQ(3, bp,
1383                     "Synchronization request half-finished.");
1384                 bp->bio_cmd = BIO_WRITE;
1385                 bp->bio_cflags = 0;
1386                 cp = disk->d_consumer;
1387                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1388                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1389                     cp->acr, cp->acw, cp->ace));
1390                 cp->index++;
1391                 g_io_request(bp, cp);
1392                 return;
1393             }
1394         case BIO_WRITE:
1395             {
1396                 off_t offset;
1397                 void *data;
1398                 int i, idx;
1399
1400                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_sync_request_write,
1401                     bp->bio_error);
1402
1403                 if (bp->bio_error != 0) {
1404                         G_MIRROR_LOGREQ(0, bp,
1405                             "Synchronization request failed (error=%d).",
1406                             bp->bio_error);
1407                         g_mirror_sync_request_free(disk, bp);
1408                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
1409                         g_mirror_event_send(disk,
1410                             G_MIRROR_DISK_STATE_DISCONNECTED,
1411                             G_MIRROR_EVENT_DONTWAIT);
1412                         return;
1413                 }
1414                 G_MIRROR_LOGREQ(3, bp, "Synchronization request finished.");
1415                 sync = &disk->d_sync;
1416                 if (sync->ds_offset >= sc->sc_mediasize ||
1417                     sync->ds_consumer == NULL ||
1418                     (sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1419                         /* Don't send more synchronization requests. */
1420                         sync->ds_inflight--;
1421                         g_mirror_sync_request_free(disk, bp);
1422                         if (sync->ds_inflight > 0)
1423                                 return;
1424                         if (sync->ds_consumer == NULL ||
1425                             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1426                                 return;
1427                         }
1428                         /* Disk up-to-date, activate it. */
1429                         g_mirror_event_send(disk, G_MIRROR_DISK_STATE_ACTIVE,
1430                             G_MIRROR_EVENT_DONTWAIT);
1431                         return;
1432                 }
1433
1434                 /* Send next synchronization request. */
1435                 data = bp->bio_data;
1436                 idx = (int)(uintptr_t)bp->bio_caller1;
1437                 g_reset_bio(bp);
1438                 bp->bio_cmd = BIO_READ;
1439                 bp->bio_offset = sync->ds_offset;
1440                 bp->bio_length = MIN(MAXPHYS, sc->sc_mediasize - bp->bio_offset);
1441                 sync->ds_offset += bp->bio_length;
1442                 bp->bio_done = g_mirror_sync_done;
1443                 bp->bio_data = data;
1444                 bp->bio_from = sync->ds_consumer;
1445                 bp->bio_to = sc->sc_provider;
1446                 bp->bio_caller1 = (void *)(uintptr_t)idx;
1447                 G_MIRROR_LOGREQ(3, bp, "Sending synchronization request.");
1448                 sync->ds_consumer->index++;
1449                 /*
1450                  * Delay the request if it is colliding with a regular request.
1451                  */
1452                 if (g_mirror_regular_collision(sc, bp))
1453                         g_mirror_sync_delay(sc, bp);
1454                 else
1455                         g_io_request(bp, sync->ds_consumer);
1456
1457                 /* Release delayed requests if possible. */
1458                 g_mirror_regular_release(sc);
1459
1460                 /* Find the smallest offset */
1461                 offset = sc->sc_mediasize;
1462                 for (i = 0; i < g_mirror_syncreqs; i++) {
1463                         bp = sync->ds_bios[i];
1464                         if (bp != NULL && bp->bio_offset < offset)
1465                                 offset = bp->bio_offset;
1466                 }
1467                 if (g_mirror_sync_period > 0 &&
1468                     time_uptime - sync->ds_update_ts > g_mirror_sync_period) {
1469                         sync->ds_offset_done = offset;
1470                         g_mirror_update_metadata(disk);
1471                         sync->ds_update_ts = time_uptime;
1472                 }
1473                 return;
1474             }
1475         default:
1476                 KASSERT(1 == 0, ("Invalid command here: %u (device=%s)",
1477                     bp->bio_cmd, sc->sc_name));
1478                 break;
1479         }
1480 }
1481
1482 static void
1483 g_mirror_request_prefer(struct g_mirror_softc *sc, struct bio *bp)
1484 {
1485         struct g_mirror_disk *disk;
1486         struct g_consumer *cp;
1487         struct bio *cbp;
1488
1489         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1490                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE)
1491                         break;
1492         }
1493         if (disk == NULL) {
1494                 if (bp->bio_error == 0)
1495                         bp->bio_error = ENXIO;
1496                 g_io_deliver(bp, bp->bio_error);
1497                 return;
1498         }
1499         cbp = g_clone_bio(bp);
1500         if (cbp == NULL) {
1501                 if (bp->bio_error == 0)
1502                         bp->bio_error = ENOMEM;
1503                 g_io_deliver(bp, bp->bio_error);
1504                 return;
1505         }
1506         /*
1507          * Fill in the component buf structure.
1508          */
1509         cp = disk->d_consumer;
1510         cbp->bio_done = g_mirror_done;
1511         cbp->bio_to = cp->provider;
1512         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1513         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1514             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1515             cp->acw, cp->ace));
1516         cp->index++;
1517         g_io_request(cbp, cp);
1518 }
1519
1520 static void
1521 g_mirror_request_round_robin(struct g_mirror_softc *sc, struct bio *bp)
1522 {
1523         struct g_mirror_disk *disk;
1524         struct g_consumer *cp;
1525         struct bio *cbp;
1526
1527         disk = g_mirror_get_disk(sc);
1528         if (disk == NULL) {
1529                 if (bp->bio_error == 0)
1530                         bp->bio_error = ENXIO;
1531                 g_io_deliver(bp, bp->bio_error);
1532                 return;
1533         }
1534         cbp = g_clone_bio(bp);
1535         if (cbp == NULL) {
1536                 if (bp->bio_error == 0)
1537                         bp->bio_error = ENOMEM;
1538                 g_io_deliver(bp, bp->bio_error);
1539                 return;
1540         }
1541         /*
1542          * Fill in the component buf structure.
1543          */
1544         cp = disk->d_consumer;
1545         cbp->bio_done = g_mirror_done;
1546         cbp->bio_to = cp->provider;
1547         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1548         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1549             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1550             cp->acw, cp->ace));
1551         cp->index++;
1552         g_io_request(cbp, cp);
1553 }
1554
1555 #define TRACK_SIZE  (1 * 1024 * 1024)
1556 #define LOAD_SCALE      256
1557 #define ABS(x)          (((x) >= 0) ? (x) : (-(x)))
1558
1559 static void
1560 g_mirror_request_load(struct g_mirror_softc *sc, struct bio *bp)
1561 {
1562         struct g_mirror_disk *disk, *dp;
1563         struct g_consumer *cp;
1564         struct bio *cbp;
1565         int prio, best;
1566
1567         /* Find a disk with the smallest load. */
1568         disk = NULL;
1569         best = INT_MAX;
1570         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
1571                 if (dp->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1572                         continue;
1573                 prio = dp->load;
1574                 /* If disk head is precisely in position - highly prefer it. */
1575                 if (dp->d_last_offset == bp->bio_offset)
1576                         prio -= 2 * LOAD_SCALE;
1577                 else
1578                 /* If disk head is close to position - prefer it. */
1579                 if (ABS(dp->d_last_offset - bp->bio_offset) < TRACK_SIZE)
1580                         prio -= 1 * LOAD_SCALE;
1581                 if (prio <= best) {
1582                         disk = dp;
1583                         best = prio;
1584                 }
1585         }
1586         KASSERT(disk != NULL, ("NULL disk for %s.", sc->sc_name));
1587         cbp = g_clone_bio(bp);
1588         if (cbp == NULL) {
1589                 if (bp->bio_error == 0)
1590                         bp->bio_error = ENOMEM;
1591                 g_io_deliver(bp, bp->bio_error);
1592                 return;
1593         }
1594         /*
1595          * Fill in the component buf structure.
1596          */
1597         cp = disk->d_consumer;
1598         cbp->bio_done = g_mirror_done;
1599         cbp->bio_to = cp->provider;
1600         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1601         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1602             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1603             cp->acw, cp->ace));
1604         cp->index++;
1605         /* Remember last head position */
1606         disk->d_last_offset = bp->bio_offset + bp->bio_length;
1607         /* Update loads. */
1608         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
1609                 dp->load = (dp->d_consumer->index * LOAD_SCALE +
1610                     dp->load * 7) / 8;
1611         }
1612         g_io_request(cbp, cp);
1613 }
1614
1615 static void
1616 g_mirror_request_split(struct g_mirror_softc *sc, struct bio *bp)
1617 {
1618         struct bio_queue_head queue;
1619         struct g_mirror_disk *disk;
1620         struct g_consumer *cp;
1621         struct bio *cbp;
1622         off_t left, mod, offset, slice;
1623         u_char *data;
1624         u_int ndisks;
1625
1626         if (bp->bio_length <= sc->sc_slice) {
1627                 g_mirror_request_round_robin(sc, bp);
1628                 return;
1629         }
1630         ndisks = g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE);
1631         slice = bp->bio_length / ndisks;
1632         mod = slice % sc->sc_provider->sectorsize;
1633         if (mod != 0)
1634                 slice += sc->sc_provider->sectorsize - mod;
1635         /*
1636          * Allocate all bios before sending any request, so we can
1637          * return ENOMEM in nice and clean way.
1638          */
1639         left = bp->bio_length;
1640         offset = bp->bio_offset;
1641         data = bp->bio_data;
1642         bioq_init(&queue);
1643         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1644                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1645                         continue;
1646                 cbp = g_clone_bio(bp);
1647                 if (cbp == NULL) {
1648                         while ((cbp = bioq_takefirst(&queue)) != NULL)
1649                                 g_destroy_bio(cbp);
1650                         if (bp->bio_error == 0)
1651                                 bp->bio_error = ENOMEM;
1652                         g_io_deliver(bp, bp->bio_error);
1653                         return;
1654                 }
1655                 bioq_insert_tail(&queue, cbp);
1656                 cbp->bio_done = g_mirror_done;
1657                 cbp->bio_caller1 = disk;
1658                 cbp->bio_to = disk->d_consumer->provider;
1659                 cbp->bio_offset = offset;
1660                 cbp->bio_data = data;
1661                 cbp->bio_length = MIN(left, slice);
1662                 left -= cbp->bio_length;
1663                 if (left == 0)
1664                         break;
1665                 offset += cbp->bio_length;
1666                 data += cbp->bio_length;
1667         }
1668         while ((cbp = bioq_takefirst(&queue)) != NULL) {
1669                 G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1670                 disk = cbp->bio_caller1;
1671                 cbp->bio_caller1 = NULL;
1672                 cp = disk->d_consumer;
1673                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1674                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1675                     cp->acr, cp->acw, cp->ace));
1676                 disk->d_consumer->index++;
1677                 g_io_request(cbp, disk->d_consumer);
1678         }
1679 }
1680
1681 static void
1682 g_mirror_register_request(struct bio *bp)
1683 {
1684         struct g_mirror_softc *sc;
1685
1686         sc = bp->bio_to->private;
1687         switch (bp->bio_cmd) {
1688         case BIO_READ:
1689                 switch (sc->sc_balance) {
1690                 case G_MIRROR_BALANCE_LOAD:
1691                         g_mirror_request_load(sc, bp);
1692                         break;
1693                 case G_MIRROR_BALANCE_PREFER:
1694                         g_mirror_request_prefer(sc, bp);
1695                         break;
1696                 case G_MIRROR_BALANCE_ROUND_ROBIN:
1697                         g_mirror_request_round_robin(sc, bp);
1698                         break;
1699                 case G_MIRROR_BALANCE_SPLIT:
1700                         g_mirror_request_split(sc, bp);
1701                         break;
1702                 }
1703                 return;
1704         case BIO_WRITE:
1705         case BIO_DELETE:
1706             {
1707                 struct g_mirror_disk *disk;
1708                 struct g_mirror_disk_sync *sync;
1709                 struct bio_queue_head queue;
1710                 struct g_consumer *cp;
1711                 struct bio *cbp;
1712
1713                 /*
1714                  * Delay the request if it is colliding with a synchronization
1715                  * request.
1716                  */
1717                 if (g_mirror_sync_collision(sc, bp)) {
1718                         g_mirror_regular_delay(sc, bp);
1719                         return;
1720                 }
1721
1722                 if (sc->sc_idle)
1723                         g_mirror_unidle(sc);
1724                 else
1725                         sc->sc_last_write = time_uptime;
1726
1727                 /*
1728                  * Bump syncid on first write.
1729                  */
1730                 if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID) != 0) {
1731                         sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID;
1732                         g_mirror_bump_syncid(sc);
1733                 }
1734
1735                 /*
1736                  * Allocate all bios before sending any request, so we can
1737                  * return ENOMEM in nice and clean way.
1738                  */
1739                 bioq_init(&queue);
1740                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1741                         sync = &disk->d_sync;
1742                         switch (disk->d_state) {
1743                         case G_MIRROR_DISK_STATE_ACTIVE:
1744                                 break;
1745                         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
1746                                 if (bp->bio_offset >= sync->ds_offset)
1747                                         continue;
1748                                 break;
1749                         default:
1750                                 continue;
1751                         }
1752                         if (bp->bio_cmd == BIO_DELETE &&
1753                             (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE) == 0)
1754                                 continue;
1755                         cbp = g_clone_bio(bp);
1756                         if (cbp == NULL) {
1757                                 while ((cbp = bioq_takefirst(&queue)) != NULL)
1758                                         g_destroy_bio(cbp);
1759                                 if (bp->bio_error == 0)
1760                                         bp->bio_error = ENOMEM;
1761                                 g_io_deliver(bp, bp->bio_error);
1762                                 return;
1763                         }
1764                         bioq_insert_tail(&queue, cbp);
1765                         cbp->bio_done = g_mirror_done;
1766                         cp = disk->d_consumer;
1767                         cbp->bio_caller1 = cp;
1768                         cbp->bio_to = cp->provider;
1769                         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1770                             ("Consumer %s not opened (r%dw%de%d).",
1771                             cp->provider->name, cp->acr, cp->acw, cp->ace));
1772                 }
1773                 if (bioq_first(&queue) == NULL) {
1774                         g_io_deliver(bp, EOPNOTSUPP);
1775                         return;
1776                 }
1777                 while ((cbp = bioq_takefirst(&queue)) != NULL) {
1778                         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1779                         cp = cbp->bio_caller1;
1780                         cbp->bio_caller1 = NULL;
1781                         cp->index++;
1782                         sc->sc_writes++;
1783                         g_io_request(cbp, cp);
1784                 }
1785                 /*
1786                  * Put request onto inflight queue, so we can check if new
1787                  * synchronization requests don't collide with it.
1788                  */
1789                 bioq_insert_tail(&sc->sc_inflight, bp);
1790                 return;
1791             }
1792         default:
1793                 KASSERT(1 == 0, ("Invalid command here: %u (device=%s)",
1794                     bp->bio_cmd, sc->sc_name));
1795                 break;
1796         }
1797 }
1798
1799 static int
1800 g_mirror_can_destroy(struct g_mirror_softc *sc)
1801 {
1802         struct g_geom *gp;
1803         struct g_consumer *cp;
1804
1805         g_topology_assert();
1806         gp = sc->sc_geom;
1807         if (gp->softc == NULL)
1808                 return (1);
1809         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_TASTING) != 0)
1810                 return (0);
1811         LIST_FOREACH(cp, &gp->consumer, consumer) {
1812                 if (g_mirror_is_busy(sc, cp))
1813                         return (0);
1814         }
1815         gp = sc->sc_sync.ds_geom;
1816         LIST_FOREACH(cp, &gp->consumer, consumer) {
1817                 if (g_mirror_is_busy(sc, cp))
1818                         return (0);
1819         }
1820         G_MIRROR_DEBUG(2, "No I/O requests for %s, it can be destroyed.",
1821             sc->sc_name);
1822         return (1);
1823 }
1824
1825 static int
1826 g_mirror_try_destroy(struct g_mirror_softc *sc)
1827 {
1828
1829         if (sc->sc_rootmount != NULL) {
1830                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p", __LINE__,
1831                     sc->sc_rootmount);
1832                 root_mount_rel(sc->sc_rootmount);
1833                 sc->sc_rootmount = NULL;
1834         }
1835         g_topology_lock();
1836         if (!g_mirror_can_destroy(sc)) {
1837                 g_topology_unlock();
1838                 return (0);
1839         }
1840         sc->sc_geom->softc = NULL;
1841         sc->sc_sync.ds_geom->softc = NULL;
1842         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DRAIN) != 0) {
1843                 g_topology_unlock();
1844                 G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__,
1845                     &sc->sc_worker);
1846                 /* Unlock sc_lock here, as it can be destroyed after wakeup. */
1847                 sx_xunlock(&sc->sc_lock);
1848                 wakeup(&sc->sc_worker);
1849                 sc->sc_worker = NULL;
1850         } else {
1851                 g_topology_unlock();
1852                 g_mirror_destroy_device(sc);
1853         }
1854         return (1);
1855 }
1856
1857 /*
1858  * Worker thread.
1859  */
1860 static void
1861 g_mirror_worker(void *arg)
1862 {
1863         struct g_mirror_softc *sc;
1864         struct g_mirror_event *ep;
1865         struct bio *bp;
1866         int timeout;
1867
1868         sc = arg;
1869         thread_lock(curthread);
1870         sched_prio(curthread, PRIBIO);
1871         thread_unlock(curthread);
1872
1873         sx_xlock(&sc->sc_lock);
1874         for (;;) {
1875                 G_MIRROR_DEBUG(5, "%s: Let's see...", __func__);
1876                 /*
1877                  * First take a look at events.
1878                  * This is important to handle events before any I/O requests.
1879                  */
1880                 ep = g_mirror_event_first(sc);
1881                 if (ep != NULL) {
1882                         g_mirror_event_remove(sc, ep);
1883                         if ((ep->e_flags & G_MIRROR_EVENT_DEVICE) != 0) {
1884                                 /* Update only device status. */
1885                                 G_MIRROR_DEBUG(3,
1886                                     "Running event for device %s.",
1887                                     sc->sc_name);
1888                                 ep->e_error = 0;
1889                                 g_mirror_update_device(sc, true);
1890                         } else {
1891                                 /* Update disk status. */
1892                                 G_MIRROR_DEBUG(3, "Running event for disk %s.",
1893                                      g_mirror_get_diskname(ep->e_disk));
1894                                 ep->e_error = g_mirror_update_disk(ep->e_disk,
1895                                     ep->e_state);
1896                                 if (ep->e_error == 0)
1897                                         g_mirror_update_device(sc, false);
1898                         }
1899                         if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0) {
1900                                 KASSERT(ep->e_error == 0,
1901                                     ("Error cannot be handled."));
1902                                 g_mirror_event_free(ep);
1903                         } else {
1904                                 ep->e_flags |= G_MIRROR_EVENT_DONE;
1905                                 G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__,
1906                                     ep);
1907                                 mtx_lock(&sc->sc_events_mtx);
1908                                 wakeup(ep);
1909                                 mtx_unlock(&sc->sc_events_mtx);
1910                         }
1911                         if ((sc->sc_flags &
1912                             G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1913                                 if (g_mirror_try_destroy(sc)) {
1914                                         curthread->td_pflags &= ~TDP_GEOM;
1915                                         G_MIRROR_DEBUG(1, "Thread exiting.");
1916                                         kproc_exit(0);
1917                                 }
1918                         }
1919                         G_MIRROR_DEBUG(5, "%s: I'm here 1.", __func__);
1920                         continue;
1921                 }
1922                 /*
1923                  * Check if we can mark array as CLEAN and if we can't take
1924                  * how much seconds should we wait.
1925                  */
1926                 timeout = g_mirror_idle(sc, -1);
1927                 /*
1928                  * Now I/O requests.
1929                  */
1930                 /* Get first request from the queue. */
1931                 mtx_lock(&sc->sc_queue_mtx);
1932                 bp = bioq_takefirst(&sc->sc_queue);
1933                 if (bp == NULL) {
1934                         if ((sc->sc_flags &
1935                             G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1936                                 mtx_unlock(&sc->sc_queue_mtx);
1937                                 if (g_mirror_try_destroy(sc)) {
1938                                         curthread->td_pflags &= ~TDP_GEOM;
1939                                         G_MIRROR_DEBUG(1, "Thread exiting.");
1940                                         kproc_exit(0);
1941                                 }
1942                                 mtx_lock(&sc->sc_queue_mtx);
1943                                 if (bioq_first(&sc->sc_queue) != NULL) {
1944                                         mtx_unlock(&sc->sc_queue_mtx);
1945                                         continue;
1946                                 }
1947                         }
1948                         if (g_mirror_event_first(sc) != NULL)
1949                                 continue;
1950                         sx_xunlock(&sc->sc_lock);
1951                         MSLEEP(sc, &sc->sc_queue_mtx, PRIBIO | PDROP, "m:w1",
1952                             timeout * hz);
1953                         sx_xlock(&sc->sc_lock);
1954                         G_MIRROR_DEBUG(5, "%s: I'm here 4.", __func__);
1955                         continue;
1956                 }
1957                 mtx_unlock(&sc->sc_queue_mtx);
1958
1959                 if (bp->bio_from->geom == sc->sc_sync.ds_geom &&
1960                     (bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0) {
1961                         g_mirror_sync_request(bp);      /* READ */
1962                 } else if (bp->bio_to != sc->sc_provider) {
1963                         if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_REGULAR) != 0)
1964                                 g_mirror_regular_request(bp);
1965                         else if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0)
1966                                 g_mirror_sync_request(bp);      /* WRITE */
1967                         else {
1968                                 KASSERT(0,
1969                                     ("Invalid request cflags=0x%hx to=%s.",
1970                                     bp->bio_cflags, bp->bio_to->name));
1971                         }
1972                 } else {
1973                         g_mirror_register_request(bp);
1974                 }
1975                 G_MIRROR_DEBUG(5, "%s: I'm here 9.", __func__);
1976         }
1977 }
1978
1979 static void
1980 g_mirror_update_idle(struct g_mirror_softc *sc, struct g_mirror_disk *disk)
1981 {
1982
1983         sx_assert(&sc->sc_lock, SX_LOCKED);
1984
1985         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
1986                 return;
1987         if (!sc->sc_idle && (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) == 0) {
1988                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as dirty.",
1989                     g_mirror_get_diskname(disk), sc->sc_name);
1990                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
1991         } else if (sc->sc_idle &&
1992             (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) != 0) {
1993                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as clean.",
1994                     g_mirror_get_diskname(disk), sc->sc_name);
1995                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
1996         }
1997 }
1998
1999 static void
2000 g_mirror_sync_start(struct g_mirror_disk *disk)
2001 {
2002         struct g_mirror_softc *sc;
2003         struct g_consumer *cp;
2004         struct bio *bp;
2005         int error, i;
2006
2007         g_topology_assert_not();
2008         sc = disk->d_softc;
2009         sx_assert(&sc->sc_lock, SX_LOCKED);
2010
2011         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2012             ("Disk %s is not marked for synchronization.",
2013             g_mirror_get_diskname(disk)));
2014         KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2015             ("Device not in RUNNING state (%s, %u).", sc->sc_name,
2016             sc->sc_state));
2017
2018         sx_xunlock(&sc->sc_lock);
2019         g_topology_lock();
2020         cp = g_new_consumer(sc->sc_sync.ds_geom);
2021         cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
2022         error = g_attach(cp, sc->sc_provider);
2023         KASSERT(error == 0,
2024             ("Cannot attach to %s (error=%d).", sc->sc_name, error));
2025         error = g_access(cp, 1, 0, 0);
2026         KASSERT(error == 0, ("Cannot open %s (error=%d).", sc->sc_name, error));
2027         g_topology_unlock();
2028         sx_xlock(&sc->sc_lock);
2029
2030         G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s.", sc->sc_name,
2031             g_mirror_get_diskname(disk));
2032         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) == 0)
2033                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
2034         KASSERT(disk->d_sync.ds_consumer == NULL,
2035             ("Sync consumer already exists (device=%s, disk=%s).",
2036             sc->sc_name, g_mirror_get_diskname(disk)));
2037
2038         disk->d_sync.ds_consumer = cp;
2039         disk->d_sync.ds_consumer->private = disk;
2040         disk->d_sync.ds_consumer->index = 0;
2041
2042         /*
2043          * Allocate memory for synchronization bios and initialize them.
2044          */
2045         disk->d_sync.ds_bios = malloc(sizeof(struct bio *) * g_mirror_syncreqs,
2046             M_MIRROR, M_WAITOK);
2047         for (i = 0; i < g_mirror_syncreqs; i++) {
2048                 bp = g_alloc_bio();
2049                 disk->d_sync.ds_bios[i] = bp;
2050                 bp->bio_parent = NULL;
2051                 bp->bio_cmd = BIO_READ;
2052                 bp->bio_data = malloc(MAXPHYS, M_MIRROR, M_WAITOK);
2053                 bp->bio_cflags = 0;
2054                 bp->bio_offset = disk->d_sync.ds_offset;
2055                 bp->bio_length = MIN(MAXPHYS, sc->sc_mediasize - bp->bio_offset);
2056                 disk->d_sync.ds_offset += bp->bio_length;
2057                 bp->bio_done = g_mirror_sync_done;
2058                 bp->bio_from = disk->d_sync.ds_consumer;
2059                 bp->bio_to = sc->sc_provider;
2060                 bp->bio_caller1 = (void *)(uintptr_t)i;
2061         }
2062
2063         /* Increase the number of disks in SYNCHRONIZING state. */
2064         sc->sc_sync.ds_ndisks++;
2065         /* Set the number of in-flight synchronization requests. */
2066         disk->d_sync.ds_inflight = g_mirror_syncreqs;
2067
2068         /*
2069          * Fire off first synchronization requests.
2070          */
2071         for (i = 0; i < g_mirror_syncreqs; i++) {
2072                 bp = disk->d_sync.ds_bios[i];
2073                 G_MIRROR_LOGREQ(3, bp, "Sending synchronization request.");
2074                 disk->d_sync.ds_consumer->index++;
2075                 /*
2076                  * Delay the request if it is colliding with a regular request.
2077                  */
2078                 if (g_mirror_regular_collision(sc, bp))
2079                         g_mirror_sync_delay(sc, bp);
2080                 else
2081                         g_io_request(bp, disk->d_sync.ds_consumer);
2082         }
2083 }
2084
2085 /*
2086  * Stop synchronization process.
2087  * type: 0 - synchronization finished
2088  *       1 - synchronization stopped
2089  */
2090 static void
2091 g_mirror_sync_stop(struct g_mirror_disk *disk, int type)
2092 {
2093         struct g_mirror_softc *sc;
2094         struct g_consumer *cp;
2095
2096         g_topology_assert_not();
2097         sc = disk->d_softc;
2098         sx_assert(&sc->sc_lock, SX_LOCKED);
2099
2100         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2101             ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2102             g_mirror_disk_state2str(disk->d_state)));
2103         if (disk->d_sync.ds_consumer == NULL)
2104                 return;
2105
2106         if (type == 0) {
2107                 G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s finished.",
2108                     sc->sc_name, g_mirror_get_diskname(disk));
2109         } else /* if (type == 1) */ {
2110                 G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s stopped.",
2111                     sc->sc_name, g_mirror_get_diskname(disk));
2112         }
2113         g_mirror_regular_release(sc);
2114         free(disk->d_sync.ds_bios, M_MIRROR);
2115         disk->d_sync.ds_bios = NULL;
2116         cp = disk->d_sync.ds_consumer;
2117         disk->d_sync.ds_consumer = NULL;
2118         disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2119         sc->sc_sync.ds_ndisks--;
2120         sx_xunlock(&sc->sc_lock); /* Avoid recursion on sc_lock. */
2121         g_topology_lock();
2122         g_mirror_kill_consumer(sc, cp);
2123         g_topology_unlock();
2124         sx_xlock(&sc->sc_lock);
2125 }
2126
2127 static void
2128 g_mirror_launch_provider(struct g_mirror_softc *sc)
2129 {
2130         struct g_mirror_disk *disk;
2131         struct g_provider *pp, *dp;
2132
2133         sx_assert(&sc->sc_lock, SX_LOCKED);
2134
2135         g_topology_lock();
2136         pp = g_new_providerf(sc->sc_geom, "mirror/%s", sc->sc_name);
2137         pp->flags |= G_PF_DIRECT_RECEIVE;
2138         pp->mediasize = sc->sc_mediasize;
2139         pp->sectorsize = sc->sc_sectorsize;
2140         pp->stripesize = 0;
2141         pp->stripeoffset = 0;
2142
2143         /* Splitting of unmapped BIO's could work but isn't implemented now */
2144         if (sc->sc_balance != G_MIRROR_BALANCE_SPLIT)
2145                 pp->flags |= G_PF_ACCEPT_UNMAPPED;
2146
2147         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2148                 if (disk->d_consumer && disk->d_consumer->provider) {
2149                         dp = disk->d_consumer->provider;
2150                         if (dp->stripesize > pp->stripesize) {
2151                                 pp->stripesize = dp->stripesize;
2152                                 pp->stripeoffset = dp->stripeoffset;
2153                         }
2154                         /* A provider underneath us doesn't support unmapped */
2155                         if ((dp->flags & G_PF_ACCEPT_UNMAPPED) == 0) {
2156                                 G_MIRROR_DEBUG(0, "Cancelling unmapped "
2157                                     "because of %s.", dp->name);
2158                                 pp->flags &= ~G_PF_ACCEPT_UNMAPPED;
2159                         }
2160                 }
2161         }
2162         pp->private = sc;
2163         sc->sc_refcnt++;
2164         sc->sc_provider = pp;
2165         g_error_provider(pp, 0);
2166         g_topology_unlock();
2167         G_MIRROR_DEBUG(0, "Device %s launched (%u/%u).", pp->name,
2168             g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE), sc->sc_ndisks);
2169         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2170                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
2171                         g_mirror_sync_start(disk);
2172         }
2173 }
2174
2175 static void
2176 g_mirror_destroy_provider(struct g_mirror_softc *sc)
2177 {
2178         struct g_mirror_disk *disk;
2179         struct bio *bp;
2180
2181         g_topology_assert_not();
2182         KASSERT(sc->sc_provider != NULL, ("NULL provider (device=%s).",
2183             sc->sc_name));
2184
2185         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2186                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
2187                         g_mirror_sync_stop(disk, 1);
2188         }
2189
2190         g_topology_lock();
2191         g_error_provider(sc->sc_provider, ENXIO);
2192         mtx_lock(&sc->sc_queue_mtx);
2193         while ((bp = bioq_takefirst(&sc->sc_queue)) != NULL) {
2194                 /*
2195                  * Abort any pending I/O that wasn't generated by us.
2196                  * Synchronization requests and requests destined for individual
2197                  * mirror components can be destroyed immediately.
2198                  */
2199                 if (bp->bio_to == sc->sc_provider &&
2200                     bp->bio_from->geom != sc->sc_sync.ds_geom) {
2201                         g_io_deliver(bp, ENXIO);
2202                 } else {
2203                         if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0)
2204                                 free(bp->bio_data, M_MIRROR);
2205                         g_destroy_bio(bp);
2206                 }
2207         }
2208         mtx_unlock(&sc->sc_queue_mtx);
2209         g_wither_provider(sc->sc_provider, ENXIO);
2210         sc->sc_provider = NULL;
2211         G_MIRROR_DEBUG(0, "Device %s: provider destroyed.", sc->sc_name);
2212         g_topology_unlock();
2213 }
2214
2215 static void
2216 g_mirror_go(void *arg)
2217 {
2218         struct g_mirror_softc *sc;
2219
2220         sc = arg;
2221         G_MIRROR_DEBUG(0, "Force device %s start due to timeout.", sc->sc_name);
2222         g_mirror_event_send(sc, 0,
2223             G_MIRROR_EVENT_DONTWAIT | G_MIRROR_EVENT_DEVICE);
2224 }
2225
2226 static u_int
2227 g_mirror_determine_state(struct g_mirror_disk *disk)
2228 {
2229         struct g_mirror_softc *sc;
2230         u_int state;
2231
2232         sc = disk->d_softc;
2233         if (sc->sc_syncid == disk->d_sync.ds_syncid) {
2234                 if ((disk->d_flags &
2235                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) == 0 &&
2236                     (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 0 ||
2237                      (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) == 0)) {
2238                         /* Disk does not need synchronization. */
2239                         state = G_MIRROR_DISK_STATE_ACTIVE;
2240                 } else {
2241                         if ((sc->sc_flags &
2242                              G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) == 0 ||
2243                             (disk->d_flags &
2244                              G_MIRROR_DISK_FLAG_FORCE_SYNC) != 0) {
2245                                 /*
2246                                  * We can start synchronization from
2247                                  * the stored offset.
2248                                  */
2249                                 state = G_MIRROR_DISK_STATE_SYNCHRONIZING;
2250                         } else {
2251                                 state = G_MIRROR_DISK_STATE_STALE;
2252                         }
2253                 }
2254         } else if (disk->d_sync.ds_syncid < sc->sc_syncid) {
2255                 /*
2256                  * Reset all synchronization data for this disk,
2257                  * because if it even was synchronized, it was
2258                  * synchronized to disks with different syncid.
2259                  */
2260                 disk->d_flags |= G_MIRROR_DISK_FLAG_SYNCHRONIZING;
2261                 disk->d_sync.ds_offset = 0;
2262                 disk->d_sync.ds_offset_done = 0;
2263                 disk->d_sync.ds_syncid = sc->sc_syncid;
2264                 if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) == 0 ||
2265                     (disk->d_flags & G_MIRROR_DISK_FLAG_FORCE_SYNC) != 0) {
2266                         state = G_MIRROR_DISK_STATE_SYNCHRONIZING;
2267                 } else {
2268                         state = G_MIRROR_DISK_STATE_STALE;
2269                 }
2270         } else /* if (sc->sc_syncid < disk->d_sync.ds_syncid) */ {
2271                 /*
2272                  * Not good, NOT GOOD!
2273                  * It means that mirror was started on stale disks
2274                  * and more fresh disk just arrive.
2275                  * If there were writes, mirror is broken, sorry.
2276                  * I think the best choice here is don't touch
2277                  * this disk and inform the user loudly.
2278                  */
2279                 G_MIRROR_DEBUG(0, "Device %s was started before the freshest "
2280                     "disk (%s) arrives!! It will not be connected to the "
2281                     "running device.", sc->sc_name,
2282                     g_mirror_get_diskname(disk));
2283                 g_mirror_destroy_disk(disk);
2284                 state = G_MIRROR_DISK_STATE_NONE;
2285                 /* Return immediately, because disk was destroyed. */
2286                 return (state);
2287         }
2288         G_MIRROR_DEBUG(3, "State for %s disk: %s.",
2289             g_mirror_get_diskname(disk), g_mirror_disk_state2str(state));
2290         return (state);
2291 }
2292
2293 /*
2294  * Update device state.
2295  */
2296 static void
2297 g_mirror_update_device(struct g_mirror_softc *sc, bool force)
2298 {
2299         struct g_mirror_disk *disk;
2300         u_int state;
2301
2302         sx_assert(&sc->sc_lock, SX_XLOCKED);
2303
2304         switch (sc->sc_state) {
2305         case G_MIRROR_DEVICE_STATE_STARTING:
2306             {
2307                 struct g_mirror_disk *pdisk, *tdisk;
2308                 u_int dirty, ndisks, genid, syncid;
2309                 bool broken;
2310
2311                 KASSERT(sc->sc_provider == NULL,
2312                     ("Non-NULL provider in STARTING state (%s).", sc->sc_name));
2313                 /*
2314                  * Are we ready? We are, if all disks are connected or
2315                  * if we have any disks and 'force' is true.
2316                  */
2317                 ndisks = g_mirror_ndisks(sc, -1);
2318                 if (sc->sc_ndisks == ndisks || (force && ndisks > 0)) {
2319                         ;
2320                 } else if (ndisks == 0) {
2321                         /*
2322                          * Disks went down in starting phase, so destroy
2323                          * device.
2324                          */
2325                         callout_drain(&sc->sc_callout);
2326                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2327                         G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p", __LINE__,
2328                             sc->sc_rootmount);
2329                         root_mount_rel(sc->sc_rootmount);
2330                         sc->sc_rootmount = NULL;
2331                         return;
2332                 } else {
2333                         return;
2334                 }
2335
2336                 /*
2337                  * Activate all disks with the biggest syncid.
2338                  */
2339                 if (force) {
2340                         /*
2341                          * If 'force' is true, we have been called due to
2342                          * timeout, so don't bother canceling timeout.
2343                          */
2344                         ndisks = 0;
2345                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2346                                 if ((disk->d_flags &
2347                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) == 0) {
2348                                         ndisks++;
2349                                 }
2350                         }
2351                         if (ndisks == 0) {
2352                                 /* No valid disks found, destroy device. */
2353                                 sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2354                                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p",
2355                                     __LINE__, sc->sc_rootmount);
2356                                 root_mount_rel(sc->sc_rootmount);
2357                                 sc->sc_rootmount = NULL;
2358                                 return;
2359                         }
2360                 } else {
2361                         /* Cancel timeout. */
2362                         callout_drain(&sc->sc_callout);
2363                 }
2364
2365                 /*
2366                  * Find the biggest genid.
2367                  */
2368                 genid = 0;
2369                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2370                         if (disk->d_genid > genid)
2371                                 genid = disk->d_genid;
2372                 }
2373                 sc->sc_genid = genid;
2374                 /*
2375                  * Remove all disks without the biggest genid.
2376                  */
2377                 broken = false;
2378                 LIST_FOREACH_SAFE(disk, &sc->sc_disks, d_next, tdisk) {
2379                         if (disk->d_genid < genid) {
2380                                 G_MIRROR_DEBUG(0,
2381                                     "Component %s (device %s) broken, skipping.",
2382                                     g_mirror_get_diskname(disk), sc->sc_name);
2383                                 g_mirror_destroy_disk(disk);
2384                                 /*
2385                                  * Bump the syncid in case we discover a healthy
2386                                  * replacement disk after starting the mirror.
2387                                  */
2388                                 broken = true;
2389                         }
2390                 }
2391
2392                 /*
2393                  * Find the biggest syncid.
2394                  */
2395                 syncid = 0;
2396                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2397                         if (disk->d_sync.ds_syncid > syncid)
2398                                 syncid = disk->d_sync.ds_syncid;
2399                 }
2400
2401                 /*
2402                  * Here we need to look for dirty disks and if all disks
2403                  * with the biggest syncid are dirty, we have to choose
2404                  * one with the biggest priority and rebuild the rest.
2405                  */
2406                 /*
2407                  * Find the number of dirty disks with the biggest syncid.
2408                  * Find the number of disks with the biggest syncid.
2409                  * While here, find a disk with the biggest priority.
2410                  */
2411                 dirty = ndisks = 0;
2412                 pdisk = NULL;
2413                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2414                         if (disk->d_sync.ds_syncid != syncid)
2415                                 continue;
2416                         if ((disk->d_flags &
2417                             G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2418                                 continue;
2419                         }
2420                         ndisks++;
2421                         if ((disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) != 0) {
2422                                 dirty++;
2423                                 if (pdisk == NULL ||
2424                                     pdisk->d_priority < disk->d_priority) {
2425                                         pdisk = disk;
2426                                 }
2427                         }
2428                 }
2429                 if (dirty == 0) {
2430                         /* No dirty disks at all, great. */
2431                 } else if (dirty == ndisks) {
2432                         /*
2433                          * Force synchronization for all dirty disks except one
2434                          * with the biggest priority.
2435                          */
2436                         KASSERT(pdisk != NULL, ("pdisk == NULL"));
2437                         G_MIRROR_DEBUG(1, "Using disk %s (device %s) as a "
2438                             "master disk for synchronization.",
2439                             g_mirror_get_diskname(pdisk), sc->sc_name);
2440                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2441                                 if (disk->d_sync.ds_syncid != syncid)
2442                                         continue;
2443                                 if ((disk->d_flags &
2444                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2445                                         continue;
2446                                 }
2447                                 KASSERT((disk->d_flags &
2448                                     G_MIRROR_DISK_FLAG_DIRTY) != 0,
2449                                     ("Disk %s isn't marked as dirty.",
2450                                     g_mirror_get_diskname(disk)));
2451                                 /* Skip the disk with the biggest priority. */
2452                                 if (disk == pdisk)
2453                                         continue;
2454                                 disk->d_sync.ds_syncid = 0;
2455                         }
2456                 } else if (dirty < ndisks) {
2457                         /*
2458                          * Force synchronization for all dirty disks.
2459                          * We have some non-dirty disks.
2460                          */
2461                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2462                                 if (disk->d_sync.ds_syncid != syncid)
2463                                         continue;
2464                                 if ((disk->d_flags &
2465                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2466                                         continue;
2467                                 }
2468                                 if ((disk->d_flags &
2469                                     G_MIRROR_DISK_FLAG_DIRTY) == 0) {
2470                                         continue;
2471                                 }
2472                                 disk->d_sync.ds_syncid = 0;
2473                         }
2474                 }
2475
2476                 /* Reset hint. */
2477                 sc->sc_hint = NULL;
2478                 sc->sc_syncid = syncid;
2479                 if (force || broken) {
2480                         /* Remember to bump syncid on first write. */
2481                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2482                 }
2483                 state = G_MIRROR_DEVICE_STATE_RUNNING;
2484                 G_MIRROR_DEBUG(1, "Device %s state changed from %s to %s.",
2485                     sc->sc_name, g_mirror_device_state2str(sc->sc_state),
2486                     g_mirror_device_state2str(state));
2487                 sc->sc_state = state;
2488                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2489                         state = g_mirror_determine_state(disk);
2490                         g_mirror_event_send(disk, state,
2491                             G_MIRROR_EVENT_DONTWAIT);
2492                         if (state == G_MIRROR_DISK_STATE_STALE)
2493                                 sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2494                 }
2495                 break;
2496             }
2497         case G_MIRROR_DEVICE_STATE_RUNNING:
2498                 if (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 0 &&
2499                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_NEW) == 0) {
2500                         /*
2501                          * No usable disks, so destroy the device.
2502                          */
2503                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2504                         break;
2505                 } else if (g_mirror_ndisks(sc,
2506                     G_MIRROR_DISK_STATE_ACTIVE) > 0 &&
2507                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_NEW) == 0) {
2508                         /*
2509                          * We have active disks, launch provider if it doesn't
2510                          * exist.
2511                          */
2512                         if (sc->sc_provider == NULL)
2513                                 g_mirror_launch_provider(sc);
2514                         if (sc->sc_rootmount != NULL) {
2515                                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p",
2516                                     __LINE__, sc->sc_rootmount);
2517                                 root_mount_rel(sc->sc_rootmount);
2518                                 sc->sc_rootmount = NULL;
2519                         }
2520                 }
2521                 /*
2522                  * Genid should be bumped immediately, so do it here.
2523                  */
2524                 if ((sc->sc_bump_id & G_MIRROR_BUMP_GENID) != 0) {
2525                         sc->sc_bump_id &= ~G_MIRROR_BUMP_GENID;
2526                         g_mirror_bump_genid(sc);
2527                 }
2528                 if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID_NOW) != 0) {
2529                         sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID_NOW;
2530                         g_mirror_bump_syncid(sc);
2531                 }
2532                 break;
2533         default:
2534                 KASSERT(1 == 0, ("Wrong device state (%s, %s).",
2535                     sc->sc_name, g_mirror_device_state2str(sc->sc_state)));
2536                 break;
2537         }
2538 }
2539
2540 /*
2541  * Update disk state and device state if needed.
2542  */
2543 #define DISK_STATE_CHANGED()    G_MIRROR_DEBUG(1,                       \
2544         "Disk %s state changed from %s to %s (device %s).",             \
2545         g_mirror_get_diskname(disk),                                    \
2546         g_mirror_disk_state2str(disk->d_state),                         \
2547         g_mirror_disk_state2str(state), sc->sc_name)
2548 static int
2549 g_mirror_update_disk(struct g_mirror_disk *disk, u_int state)
2550 {
2551         struct g_mirror_softc *sc;
2552
2553         sc = disk->d_softc;
2554         sx_assert(&sc->sc_lock, SX_XLOCKED);
2555
2556 again:
2557         G_MIRROR_DEBUG(3, "Changing disk %s state from %s to %s.",
2558             g_mirror_get_diskname(disk), g_mirror_disk_state2str(disk->d_state),
2559             g_mirror_disk_state2str(state));
2560         switch (state) {
2561         case G_MIRROR_DISK_STATE_NEW:
2562                 /*
2563                  * Possible scenarios:
2564                  * 1. New disk arrive.
2565                  */
2566                 /* Previous state should be NONE. */
2567                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NONE,
2568                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2569                     g_mirror_disk_state2str(disk->d_state)));
2570                 DISK_STATE_CHANGED();
2571
2572                 disk->d_state = state;
2573                 if (LIST_EMPTY(&sc->sc_disks))
2574                         LIST_INSERT_HEAD(&sc->sc_disks, disk, d_next);
2575                 else {
2576                         struct g_mirror_disk *dp;
2577
2578                         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
2579                                 if (disk->d_priority >= dp->d_priority) {
2580                                         LIST_INSERT_BEFORE(dp, disk, d_next);
2581                                         dp = NULL;
2582                                         break;
2583                                 }
2584                                 if (LIST_NEXT(dp, d_next) == NULL)
2585                                         break;
2586                         }
2587                         if (dp != NULL)
2588                                 LIST_INSERT_AFTER(dp, disk, d_next);
2589                 }
2590                 G_MIRROR_DEBUG(1, "Device %s: provider %s detected.",
2591                     sc->sc_name, g_mirror_get_diskname(disk));
2592                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING)
2593                         break;
2594                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2595                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2596                     g_mirror_device_state2str(sc->sc_state),
2597                     g_mirror_get_diskname(disk),
2598                     g_mirror_disk_state2str(disk->d_state)));
2599                 state = g_mirror_determine_state(disk);
2600                 if (state != G_MIRROR_DISK_STATE_NONE)
2601                         goto again;
2602                 break;
2603         case G_MIRROR_DISK_STATE_ACTIVE:
2604                 /*
2605                  * Possible scenarios:
2606                  * 1. New disk does not need synchronization.
2607                  * 2. Synchronization process finished successfully.
2608                  */
2609                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2610                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2611                     g_mirror_device_state2str(sc->sc_state),
2612                     g_mirror_get_diskname(disk),
2613                     g_mirror_disk_state2str(disk->d_state)));
2614                 /* Previous state should be NEW or SYNCHRONIZING. */
2615                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW ||
2616                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2617                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2618                     g_mirror_disk_state2str(disk->d_state)));
2619                 DISK_STATE_CHANGED();
2620
2621                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
2622                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_SYNCHRONIZING;
2623                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_FORCE_SYNC;
2624                         g_mirror_sync_stop(disk, 0);
2625                 }
2626                 disk->d_state = state;
2627                 disk->d_sync.ds_offset = 0;
2628                 disk->d_sync.ds_offset_done = 0;
2629                 g_mirror_update_idle(sc, disk);
2630                 g_mirror_update_metadata(disk);
2631                 G_MIRROR_DEBUG(1, "Device %s: provider %s activated.",
2632                     sc->sc_name, g_mirror_get_diskname(disk));
2633                 break;
2634         case G_MIRROR_DISK_STATE_STALE:
2635                 /*
2636                  * Possible scenarios:
2637                  * 1. Stale disk was connected.
2638                  */
2639                 /* Previous state should be NEW. */
2640                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2641                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2642                     g_mirror_disk_state2str(disk->d_state)));
2643                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2644                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2645                     g_mirror_device_state2str(sc->sc_state),
2646                     g_mirror_get_diskname(disk),
2647                     g_mirror_disk_state2str(disk->d_state)));
2648                 /*
2649                  * STALE state is only possible if device is marked
2650                  * NOAUTOSYNC.
2651                  */
2652                 KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) != 0,
2653                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2654                     g_mirror_device_state2str(sc->sc_state),
2655                     g_mirror_get_diskname(disk),
2656                     g_mirror_disk_state2str(disk->d_state)));
2657                 DISK_STATE_CHANGED();
2658
2659                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2660                 disk->d_state = state;
2661                 g_mirror_update_metadata(disk);
2662                 G_MIRROR_DEBUG(0, "Device %s: provider %s is stale.",
2663                     sc->sc_name, g_mirror_get_diskname(disk));
2664                 break;
2665         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
2666                 /*
2667                  * Possible scenarios:
2668                  * 1. Disk which needs synchronization was connected.
2669                  */
2670                 /* Previous state should be NEW. */
2671                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2672                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2673                     g_mirror_disk_state2str(disk->d_state)));
2674                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2675                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2676                     g_mirror_device_state2str(sc->sc_state),
2677                     g_mirror_get_diskname(disk),
2678                     g_mirror_disk_state2str(disk->d_state)));
2679                 DISK_STATE_CHANGED();
2680
2681                 if (disk->d_state == G_MIRROR_DISK_STATE_NEW)
2682                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2683                 disk->d_state = state;
2684                 if (sc->sc_provider != NULL) {
2685                         g_mirror_sync_start(disk);
2686                         g_mirror_update_metadata(disk);
2687                 }
2688                 break;
2689         case G_MIRROR_DISK_STATE_DISCONNECTED:
2690                 /*
2691                  * Possible scenarios:
2692                  * 1. Device wasn't running yet, but disk disappear.
2693                  * 2. Disk was active and disapppear.
2694                  * 3. Disk disappear during synchronization process.
2695                  */
2696                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING) {
2697                         /*
2698                          * Previous state should be ACTIVE, STALE or
2699                          * SYNCHRONIZING.
2700                          */
2701                         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
2702                             disk->d_state == G_MIRROR_DISK_STATE_STALE ||
2703                             disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2704                             ("Wrong disk state (%s, %s).",
2705                             g_mirror_get_diskname(disk),
2706                             g_mirror_disk_state2str(disk->d_state)));
2707                 } else if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING) {
2708                         /* Previous state should be NEW. */
2709                         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2710                             ("Wrong disk state (%s, %s).",
2711                             g_mirror_get_diskname(disk),
2712                             g_mirror_disk_state2str(disk->d_state)));
2713                         /*
2714                          * Reset bumping syncid if disk disappeared in STARTING
2715                          * state.
2716                          */
2717                         if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID) != 0)
2718                                 sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID;
2719 #ifdef  INVARIANTS
2720                 } else {
2721                         KASSERT(1 == 0, ("Wrong device state (%s, %s, %s, %s).",
2722                             sc->sc_name,
2723                             g_mirror_device_state2str(sc->sc_state),
2724                             g_mirror_get_diskname(disk),
2725                             g_mirror_disk_state2str(disk->d_state)));
2726 #endif
2727                 }
2728                 DISK_STATE_CHANGED();
2729                 G_MIRROR_DEBUG(0, "Device %s: provider %s disconnected.",
2730                     sc->sc_name, g_mirror_get_diskname(disk));
2731
2732                 g_mirror_destroy_disk(disk);
2733                 break;
2734         case G_MIRROR_DISK_STATE_DESTROY:
2735             {
2736                 int error;
2737
2738                 error = g_mirror_clear_metadata(disk);
2739                 if (error != 0) {
2740                         G_MIRROR_DEBUG(0,
2741                             "Device %s: failed to clear metadata on %s: %d.",
2742                             sc->sc_name, g_mirror_get_diskname(disk), error);
2743                         break;
2744                 }
2745                 DISK_STATE_CHANGED();
2746                 G_MIRROR_DEBUG(0, "Device %s: provider %s destroyed.",
2747                     sc->sc_name, g_mirror_get_diskname(disk));
2748
2749                 g_mirror_destroy_disk(disk);
2750                 sc->sc_ndisks--;
2751                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2752                         g_mirror_update_metadata(disk);
2753                 }
2754                 break;
2755             }
2756         default:
2757                 KASSERT(1 == 0, ("Unknown state (%u).", state));
2758                 break;
2759         }
2760         return (0);
2761 }
2762 #undef  DISK_STATE_CHANGED
2763
2764 int
2765 g_mirror_read_metadata(struct g_consumer *cp, struct g_mirror_metadata *md)
2766 {
2767         struct g_provider *pp;
2768         u_char *buf;
2769         int error;
2770
2771         g_topology_assert();
2772
2773         error = g_access(cp, 1, 0, 0);
2774         if (error != 0)
2775                 return (error);
2776         pp = cp->provider;
2777         g_topology_unlock();
2778         /* Metadata are stored on last sector. */
2779         buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
2780             &error);
2781         g_topology_lock();
2782         g_access(cp, -1, 0, 0);
2783         if (buf == NULL) {
2784                 G_MIRROR_DEBUG(1, "Cannot read metadata from %s (error=%d).",
2785                     cp->provider->name, error);
2786                 return (error);
2787         }
2788
2789         /* Decode metadata. */
2790         error = mirror_metadata_decode(buf, md);
2791         g_free(buf);
2792         if (strcmp(md->md_magic, G_MIRROR_MAGIC) != 0)
2793                 return (EINVAL);
2794         if (md->md_version > G_MIRROR_VERSION) {
2795                 G_MIRROR_DEBUG(0,
2796                     "Kernel module is too old to handle metadata from %s.",
2797                     cp->provider->name);
2798                 return (EINVAL);
2799         }
2800         if (error != 0) {
2801                 G_MIRROR_DEBUG(1, "MD5 metadata hash mismatch for provider %s.",
2802                     cp->provider->name);
2803                 return (error);
2804         }
2805
2806         return (0);
2807 }
2808
2809 static int
2810 g_mirror_check_metadata(struct g_mirror_softc *sc, struct g_provider *pp,
2811     struct g_mirror_metadata *md)
2812 {
2813
2814         if (g_mirror_id2disk(sc, md->md_did) != NULL) {
2815                 G_MIRROR_DEBUG(1, "Disk %s (id=%u) already exists, skipping.",
2816                     pp->name, md->md_did);
2817                 return (EEXIST);
2818         }
2819         if (md->md_all != sc->sc_ndisks) {
2820                 G_MIRROR_DEBUG(1,
2821                     "Invalid '%s' field on disk %s (device %s), skipping.",
2822                     "md_all", pp->name, sc->sc_name);
2823                 return (EINVAL);
2824         }
2825         if (md->md_slice != sc->sc_slice) {
2826                 G_MIRROR_DEBUG(1,
2827                     "Invalid '%s' field on disk %s (device %s), skipping.",
2828                     "md_slice", pp->name, sc->sc_name);
2829                 return (EINVAL);
2830         }
2831         if (md->md_balance != sc->sc_balance) {
2832                 G_MIRROR_DEBUG(1,
2833                     "Invalid '%s' field on disk %s (device %s), skipping.",
2834                     "md_balance", pp->name, sc->sc_name);
2835                 return (EINVAL);
2836         }
2837 #if 0
2838         if (md->md_mediasize != sc->sc_mediasize) {
2839                 G_MIRROR_DEBUG(1,
2840                     "Invalid '%s' field on disk %s (device %s), skipping.",
2841                     "md_mediasize", pp->name, sc->sc_name);
2842                 return (EINVAL);
2843         }
2844 #endif
2845         if (sc->sc_mediasize > pp->mediasize) {
2846                 G_MIRROR_DEBUG(1,
2847                     "Invalid size of disk %s (device %s), skipping.", pp->name,
2848                     sc->sc_name);
2849                 return (EINVAL);
2850         }
2851         if (md->md_sectorsize != sc->sc_sectorsize) {
2852                 G_MIRROR_DEBUG(1,
2853                     "Invalid '%s' field on disk %s (device %s), skipping.",
2854                     "md_sectorsize", pp->name, sc->sc_name);
2855                 return (EINVAL);
2856         }
2857         if ((sc->sc_sectorsize % pp->sectorsize) != 0) {
2858                 G_MIRROR_DEBUG(1,
2859                     "Invalid sector size of disk %s (device %s), skipping.",
2860                     pp->name, sc->sc_name);
2861                 return (EINVAL);
2862         }
2863         if ((md->md_mflags & ~G_MIRROR_DEVICE_FLAG_MASK) != 0) {
2864                 G_MIRROR_DEBUG(1,
2865                     "Invalid device flags on disk %s (device %s), skipping.",
2866                     pp->name, sc->sc_name);
2867                 return (EINVAL);
2868         }
2869         if ((md->md_dflags & ~G_MIRROR_DISK_FLAG_MASK) != 0) {
2870                 G_MIRROR_DEBUG(1,
2871                     "Invalid disk flags on disk %s (device %s), skipping.",
2872                     pp->name, sc->sc_name);
2873                 return (EINVAL);
2874         }
2875         return (0);
2876 }
2877
2878 int
2879 g_mirror_add_disk(struct g_mirror_softc *sc, struct g_provider *pp,
2880     struct g_mirror_metadata *md)
2881 {
2882         struct g_mirror_disk *disk;
2883         int error;
2884
2885         g_topology_assert_not();
2886         G_MIRROR_DEBUG(2, "Adding disk %s.", pp->name);
2887
2888         error = g_mirror_check_metadata(sc, pp, md);
2889         if (error != 0)
2890                 return (error);
2891         if (sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING &&
2892             md->md_genid < sc->sc_genid) {
2893                 G_MIRROR_DEBUG(0, "Component %s (device %s) broken, skipping.",
2894                     pp->name, sc->sc_name);
2895                 return (EINVAL);
2896         }
2897         disk = g_mirror_init_disk(sc, pp, md, &error);
2898         if (disk == NULL)
2899                 return (error);
2900         error = g_mirror_event_send(disk, G_MIRROR_DISK_STATE_NEW,
2901             G_MIRROR_EVENT_WAIT);
2902         if (error != 0)
2903                 return (error);
2904         if (md->md_version < G_MIRROR_VERSION) {
2905                 G_MIRROR_DEBUG(0, "Upgrading metadata on %s (v%d->v%d).",
2906                     pp->name, md->md_version, G_MIRROR_VERSION);
2907                 g_mirror_update_metadata(disk);
2908         }
2909         return (0);
2910 }
2911
2912 static void
2913 g_mirror_destroy_delayed(void *arg, int flag)
2914 {
2915         struct g_mirror_softc *sc;
2916         int error;
2917
2918         if (flag == EV_CANCEL) {
2919                 G_MIRROR_DEBUG(1, "Destroying canceled.");
2920                 return;
2921         }
2922         sc = arg;
2923         g_topology_unlock();
2924         sx_xlock(&sc->sc_lock);
2925         KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) == 0,
2926             ("DESTROY flag set on %s.", sc->sc_name));
2927         KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0,
2928             ("CLOSEWAIT flag not set on %s.", sc->sc_name));
2929         G_MIRROR_DEBUG(1, "Destroying %s (delayed).", sc->sc_name);
2930         error = g_mirror_destroy(sc, G_MIRROR_DESTROY_SOFT);
2931         if (error != 0) {
2932                 G_MIRROR_DEBUG(0, "Cannot destroy %s (error=%d).",
2933                     sc->sc_name, error);
2934                 sx_xunlock(&sc->sc_lock);
2935         }
2936         g_topology_lock();
2937 }
2938
2939 static int
2940 g_mirror_access(struct g_provider *pp, int acr, int acw, int ace)
2941 {
2942         struct g_mirror_softc *sc;
2943         int error = 0;
2944
2945         g_topology_assert();
2946         G_MIRROR_DEBUG(2, "Access request for %s: r%dw%de%d.", pp->name, acr,
2947             acw, ace);
2948
2949         sc = pp->private;
2950         KASSERT(sc != NULL, ("NULL softc (provider=%s).", pp->name));
2951
2952         g_topology_unlock();
2953         sx_xlock(&sc->sc_lock);
2954         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0 ||
2955             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0 ||
2956             LIST_EMPTY(&sc->sc_disks)) {
2957                 if (acr > 0 || acw > 0 || ace > 0)
2958                         error = ENXIO;
2959                 goto end;
2960         }
2961         sc->sc_provider_open += acr + acw + ace;
2962         if (pp->acw + acw == 0)
2963                 g_mirror_idle(sc, 0);
2964         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0 &&
2965             sc->sc_provider_open == 0)
2966                 g_post_event(g_mirror_destroy_delayed, sc, M_WAITOK, sc, NULL);
2967 end:
2968         sx_xunlock(&sc->sc_lock);
2969         g_topology_lock();
2970         return (error);
2971 }
2972
2973 struct g_geom *
2974 g_mirror_create(struct g_class *mp, const struct g_mirror_metadata *md,
2975     u_int type)
2976 {
2977         struct g_mirror_softc *sc;
2978         struct g_geom *gp;
2979         int error, timeout;
2980
2981         g_topology_assert();
2982         G_MIRROR_DEBUG(1, "Creating device %s (id=%u).", md->md_name,
2983             md->md_mid);
2984
2985         /* One disk is minimum. */
2986         if (md->md_all < 1)
2987                 return (NULL);
2988         /*
2989          * Action geom.
2990          */
2991         gp = g_new_geomf(mp, "%s", md->md_name);
2992         sc = malloc(sizeof(*sc), M_MIRROR, M_WAITOK | M_ZERO);
2993         gp->start = g_mirror_start;
2994         gp->orphan = g_mirror_orphan;
2995         gp->access = g_mirror_access;
2996         gp->dumpconf = g_mirror_dumpconf;
2997
2998         sc->sc_type = type;
2999         sc->sc_id = md->md_mid;
3000         sc->sc_slice = md->md_slice;
3001         sc->sc_balance = md->md_balance;
3002         sc->sc_mediasize = md->md_mediasize;
3003         sc->sc_sectorsize = md->md_sectorsize;
3004         sc->sc_ndisks = md->md_all;
3005         sc->sc_flags = md->md_mflags;
3006         sc->sc_bump_id = 0;
3007         sc->sc_idle = 1;
3008         sc->sc_last_write = time_uptime;
3009         sc->sc_writes = 0;
3010         sc->sc_refcnt = 1;
3011         sx_init(&sc->sc_lock, "gmirror:lock");
3012         bioq_init(&sc->sc_queue);
3013         mtx_init(&sc->sc_queue_mtx, "gmirror:queue", NULL, MTX_DEF);
3014         bioq_init(&sc->sc_regular_delayed);
3015         bioq_init(&sc->sc_inflight);
3016         bioq_init(&sc->sc_sync_delayed);
3017         LIST_INIT(&sc->sc_disks);
3018         TAILQ_INIT(&sc->sc_events);
3019         mtx_init(&sc->sc_events_mtx, "gmirror:events", NULL, MTX_DEF);
3020         callout_init(&sc->sc_callout, 1);
3021         mtx_init(&sc->sc_done_mtx, "gmirror:done", NULL, MTX_DEF);
3022         sc->sc_state = G_MIRROR_DEVICE_STATE_STARTING;
3023         gp->softc = sc;
3024         sc->sc_geom = gp;
3025         sc->sc_provider = NULL;
3026         sc->sc_provider_open = 0;
3027         /*
3028          * Synchronization geom.
3029          */
3030         gp = g_new_geomf(mp, "%s.sync", md->md_name);
3031         gp->softc = sc;
3032         gp->orphan = g_mirror_orphan;
3033         sc->sc_sync.ds_geom = gp;
3034         sc->sc_sync.ds_ndisks = 0;
3035         error = kproc_create(g_mirror_worker, sc, &sc->sc_worker, 0, 0,
3036             "g_mirror %s", md->md_name);
3037         if (error != 0) {
3038                 G_MIRROR_DEBUG(1, "Cannot create kernel thread for %s.",
3039                     sc->sc_name);
3040                 g_destroy_geom(sc->sc_sync.ds_geom);
3041                 g_destroy_geom(sc->sc_geom);
3042                 g_mirror_free_device(sc);
3043                 return (NULL);
3044         }
3045
3046         G_MIRROR_DEBUG(1, "Device %s created (%u components, id=%u).",
3047             sc->sc_name, sc->sc_ndisks, sc->sc_id);
3048
3049         sc->sc_rootmount = root_mount_hold("GMIRROR");
3050         G_MIRROR_DEBUG(1, "root_mount_hold %p", sc->sc_rootmount);
3051         /*
3052          * Run timeout.
3053          */
3054         timeout = g_mirror_timeout * hz;
3055         callout_reset(&sc->sc_callout, timeout, g_mirror_go, sc);
3056         return (sc->sc_geom);
3057 }
3058
3059 int
3060 g_mirror_destroy(struct g_mirror_softc *sc, int how)
3061 {
3062         struct g_mirror_disk *disk;
3063
3064         g_topology_assert_not();
3065         sx_assert(&sc->sc_lock, SX_XLOCKED);
3066
3067         if (sc->sc_provider_open != 0) {
3068                 switch (how) {
3069                 case G_MIRROR_DESTROY_SOFT:
3070                         G_MIRROR_DEBUG(1,
3071                             "Device %s is still open (%d).", sc->sc_name,
3072                             sc->sc_provider_open);
3073                         return (EBUSY);
3074                 case G_MIRROR_DESTROY_DELAYED:
3075                         G_MIRROR_DEBUG(1,
3076                             "Device %s will be destroyed on last close.",
3077                             sc->sc_name);
3078                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
3079                                 if (disk->d_state ==
3080                                     G_MIRROR_DISK_STATE_SYNCHRONIZING) {
3081                                         g_mirror_sync_stop(disk, 1);
3082                                 }
3083                         }
3084                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_CLOSEWAIT;
3085                         return (EBUSY);
3086                 case G_MIRROR_DESTROY_HARD:
3087                         G_MIRROR_DEBUG(1, "Device %s is still open, so it "
3088                             "can't be definitely removed.", sc->sc_name);
3089                 }
3090         }
3091
3092         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
3093                 sx_xunlock(&sc->sc_lock);
3094                 return (0);
3095         }
3096         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
3097         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DRAIN;
3098         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
3099         sx_xunlock(&sc->sc_lock);
3100         mtx_lock(&sc->sc_queue_mtx);
3101         wakeup(sc);
3102         mtx_unlock(&sc->sc_queue_mtx);
3103         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, &sc->sc_worker);
3104         while (sc->sc_worker != NULL)
3105                 tsleep(&sc->sc_worker, PRIBIO, "m:destroy", hz / 5);
3106         G_MIRROR_DEBUG(4, "%s: Woken up %p.", __func__, &sc->sc_worker);
3107         sx_xlock(&sc->sc_lock);
3108         g_mirror_destroy_device(sc);
3109         return (0);
3110 }
3111
3112 static void
3113 g_mirror_taste_orphan(struct g_consumer *cp)
3114 {
3115
3116         KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
3117             cp->provider->name));
3118 }
3119
3120 static struct g_geom *
3121 g_mirror_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
3122 {
3123         struct g_mirror_metadata md;
3124         struct g_mirror_softc *sc;
3125         struct g_consumer *cp;
3126         struct g_geom *gp;
3127         int error;
3128
3129         g_topology_assert();
3130         g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
3131         G_MIRROR_DEBUG(2, "Tasting %s.", pp->name);
3132
3133         gp = g_new_geomf(mp, "mirror:taste");
3134         /*
3135          * This orphan function should be never called.
3136          */
3137         gp->orphan = g_mirror_taste_orphan;
3138         cp = g_new_consumer(gp);
3139         g_attach(cp, pp);
3140         error = g_mirror_read_metadata(cp, &md);
3141         g_detach(cp);
3142         g_destroy_consumer(cp);
3143         g_destroy_geom(gp);
3144         if (error != 0)
3145                 return (NULL);
3146         gp = NULL;
3147
3148         if (md.md_provider[0] != '\0' &&
3149             !g_compare_names(md.md_provider, pp->name))
3150                 return (NULL);
3151         if (md.md_provsize != 0 && md.md_provsize != pp->mediasize)
3152                 return (NULL);
3153         if ((md.md_dflags & G_MIRROR_DISK_FLAG_INACTIVE) != 0) {
3154                 G_MIRROR_DEBUG(0,
3155                     "Device %s: provider %s marked as inactive, skipping.",
3156                     md.md_name, pp->name);
3157                 return (NULL);
3158         }
3159         if (g_mirror_debug >= 2)
3160                 mirror_metadata_dump(&md);
3161
3162         /*
3163          * Let's check if device already exists.
3164          */
3165         sc = NULL;
3166         LIST_FOREACH(gp, &mp->geom, geom) {
3167                 sc = gp->softc;
3168                 if (sc == NULL)
3169                         continue;
3170                 if (sc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
3171                         continue;
3172                 if (sc->sc_sync.ds_geom == gp)
3173                         continue;
3174                 if (strcmp(md.md_name, sc->sc_name) != 0)
3175                         continue;
3176                 if (md.md_mid != sc->sc_id) {
3177                         G_MIRROR_DEBUG(0, "Device %s already configured.",
3178                             sc->sc_name);
3179                         return (NULL);
3180                 }
3181                 break;
3182         }
3183         if (gp == NULL) {
3184                 gp = g_mirror_create(mp, &md, G_MIRROR_TYPE_AUTOMATIC);
3185                 if (gp == NULL) {
3186                         G_MIRROR_DEBUG(0, "Cannot create device %s.",
3187                             md.md_name);
3188                         return (NULL);
3189                 }
3190                 sc = gp->softc;
3191         }
3192         G_MIRROR_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
3193         g_topology_unlock();
3194         sx_xlock(&sc->sc_lock);
3195         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_TASTING;
3196         error = g_mirror_add_disk(sc, pp, &md);
3197         if (error != 0) {
3198                 G_MIRROR_DEBUG(0, "Cannot add disk %s to %s (error=%d).",
3199                     pp->name, gp->name, error);
3200                 if (LIST_EMPTY(&sc->sc_disks)) {
3201                         g_cancel_event(sc);
3202                         g_mirror_destroy(sc, G_MIRROR_DESTROY_HARD);
3203                         g_topology_lock();
3204                         return (NULL);
3205                 }
3206                 gp = NULL;
3207         }
3208         sc->sc_flags &= ~G_MIRROR_DEVICE_FLAG_TASTING;
3209         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
3210                 g_mirror_destroy(sc, G_MIRROR_DESTROY_HARD);
3211                 g_topology_lock();
3212                 return (NULL);
3213         }
3214         sx_xunlock(&sc->sc_lock);
3215         g_topology_lock();
3216         return (gp);
3217 }
3218
3219 static void
3220 g_mirror_resize(struct g_consumer *cp)
3221 {
3222         struct g_mirror_disk *disk;
3223
3224         g_topology_assert();
3225         g_trace(G_T_TOPOLOGY, "%s(%s)", __func__, cp->provider->name);
3226
3227         disk = cp->private;
3228         if (disk == NULL)
3229                 return;
3230         g_topology_unlock();
3231         g_mirror_update_metadata(disk);
3232         g_topology_lock();
3233 }
3234
3235 static int
3236 g_mirror_destroy_geom(struct gctl_req *req __unused,
3237     struct g_class *mp __unused, struct g_geom *gp)
3238 {
3239         struct g_mirror_softc *sc;
3240         int error;
3241
3242         g_topology_unlock();
3243         sc = gp->softc;
3244         sx_xlock(&sc->sc_lock);
3245         g_cancel_event(sc);
3246         error = g_mirror_destroy(gp->softc, G_MIRROR_DESTROY_SOFT);
3247         if (error != 0)
3248                 sx_xunlock(&sc->sc_lock);
3249         g_topology_lock();
3250         return (error);
3251 }
3252
3253 static void
3254 g_mirror_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
3255     struct g_consumer *cp, struct g_provider *pp)
3256 {
3257         struct g_mirror_softc *sc;
3258
3259         g_topology_assert();
3260
3261         sc = gp->softc;
3262         if (sc == NULL)
3263                 return;
3264         /* Skip synchronization geom. */
3265         if (gp == sc->sc_sync.ds_geom)
3266                 return;
3267         if (pp != NULL) {
3268                 /* Nothing here. */
3269         } else if (cp != NULL) {
3270                 struct g_mirror_disk *disk;
3271
3272                 disk = cp->private;
3273                 if (disk == NULL)
3274                         return;
3275                 g_topology_unlock();
3276                 sx_xlock(&sc->sc_lock);
3277                 sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)disk->d_id);
3278                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
3279                         sbuf_printf(sb, "%s<Synchronized>", indent);
3280                         if (disk->d_sync.ds_offset == 0)
3281                                 sbuf_printf(sb, "0%%");
3282                         else {
3283                                 sbuf_printf(sb, "%u%%",
3284                                     (u_int)((disk->d_sync.ds_offset * 100) /
3285                                     sc->sc_provider->mediasize));
3286                         }
3287                         sbuf_printf(sb, "</Synchronized>\n");
3288                         if (disk->d_sync.ds_offset > 0) {
3289                                 sbuf_printf(sb, "%s<BytesSynced>%jd"
3290                                     "</BytesSynced>\n", indent,
3291                                     (intmax_t)disk->d_sync.ds_offset);
3292                         }
3293                 }
3294                 sbuf_printf(sb, "%s<SyncID>%u</SyncID>\n", indent,
3295                     disk->d_sync.ds_syncid);
3296                 sbuf_printf(sb, "%s<GenID>%u</GenID>\n", indent,
3297                     disk->d_genid);
3298                 sbuf_printf(sb, "%s<Flags>", indent);
3299                 if (disk->d_flags == 0)
3300                         sbuf_printf(sb, "NONE");
3301                 else {
3302                         int first = 1;
3303
3304 #define ADD_FLAG(flag, name)    do {                                    \
3305         if ((disk->d_flags & (flag)) != 0) {                            \
3306                 if (!first)                                             \
3307                         sbuf_printf(sb, ", ");                          \
3308                 else                                                    \
3309                         first = 0;                                      \
3310                 sbuf_printf(sb, name);                                  \
3311         }                                                               \
3312 } while (0)
3313                         ADD_FLAG(G_MIRROR_DISK_FLAG_DIRTY, "DIRTY");
3314                         ADD_FLAG(G_MIRROR_DISK_FLAG_HARDCODED, "HARDCODED");
3315                         ADD_FLAG(G_MIRROR_DISK_FLAG_INACTIVE, "INACTIVE");
3316                         ADD_FLAG(G_MIRROR_DISK_FLAG_SYNCHRONIZING,
3317                             "SYNCHRONIZING");
3318                         ADD_FLAG(G_MIRROR_DISK_FLAG_FORCE_SYNC, "FORCE_SYNC");
3319                         ADD_FLAG(G_MIRROR_DISK_FLAG_BROKEN, "BROKEN");
3320 #undef  ADD_FLAG
3321                 }
3322                 sbuf_printf(sb, "</Flags>\n");
3323                 sbuf_printf(sb, "%s<Priority>%u</Priority>\n", indent,
3324                     disk->d_priority);
3325                 sbuf_printf(sb, "%s<State>%s</State>\n", indent,
3326                     g_mirror_disk_state2str(disk->d_state));
3327                 sx_xunlock(&sc->sc_lock);
3328                 g_topology_lock();
3329         } else {
3330                 g_topology_unlock();
3331                 sx_xlock(&sc->sc_lock);
3332                 sbuf_printf(sb, "%s<Type>", indent);
3333                 switch (sc->sc_type) {
3334                 case G_MIRROR_TYPE_AUTOMATIC:
3335                         sbuf_printf(sb, "AUTOMATIC");
3336                         break;
3337                 case G_MIRROR_TYPE_MANUAL:
3338                         sbuf_printf(sb, "MANUAL");
3339                         break;
3340                 default:
3341                         sbuf_printf(sb, "UNKNOWN");
3342                         break;
3343                 }
3344                 sbuf_printf(sb, "</Type>\n");
3345                 sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)sc->sc_id);
3346                 sbuf_printf(sb, "%s<SyncID>%u</SyncID>\n", indent, sc->sc_syncid);
3347                 sbuf_printf(sb, "%s<GenID>%u</GenID>\n", indent, sc->sc_genid);
3348                 sbuf_printf(sb, "%s<Flags>", indent);
3349                 if (sc->sc_flags == 0)
3350                         sbuf_printf(sb, "NONE");
3351                 else {
3352                         int first = 1;
3353
3354 #define ADD_FLAG(flag, name)    do {                                    \
3355         if ((sc->sc_flags & (flag)) != 0) {                             \
3356                 if (!first)                                             \
3357                         sbuf_printf(sb, ", ");                          \
3358                 else                                                    \
3359                         first = 0;                                      \
3360                 sbuf_printf(sb, name);                                  \
3361         }                                                               \
3362 } while (0)
3363                         ADD_FLAG(G_MIRROR_DEVICE_FLAG_NOFAILSYNC, "NOFAILSYNC");
3364                         ADD_FLAG(G_MIRROR_DEVICE_FLAG_NOAUTOSYNC, "NOAUTOSYNC");
3365 #undef  ADD_FLAG
3366                 }
3367                 sbuf_printf(sb, "</Flags>\n");
3368                 sbuf_printf(sb, "%s<Slice>%u</Slice>\n", indent,
3369                     (u_int)sc->sc_slice);
3370                 sbuf_printf(sb, "%s<Balance>%s</Balance>\n", indent,
3371                     balance_name(sc->sc_balance));
3372                 sbuf_printf(sb, "%s<Components>%u</Components>\n", indent,
3373                     sc->sc_ndisks);
3374                 sbuf_printf(sb, "%s<State>", indent);
3375                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING)
3376                         sbuf_printf(sb, "%s", "STARTING");
3377                 else if (sc->sc_ndisks ==
3378                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE))
3379                         sbuf_printf(sb, "%s", "COMPLETE");
3380                 else
3381                         sbuf_printf(sb, "%s", "DEGRADED");
3382                 sbuf_printf(sb, "</State>\n");
3383                 sx_xunlock(&sc->sc_lock);
3384                 g_topology_lock();
3385         }
3386 }
3387
3388 static void
3389 g_mirror_shutdown_post_sync(void *arg, int howto)
3390 {
3391         struct g_class *mp;
3392         struct g_geom *gp, *gp2;
3393         struct g_mirror_softc *sc;
3394         int error;
3395
3396         if (panicstr != NULL)
3397                 return;
3398
3399         mp = arg;
3400         g_topology_lock();
3401         g_mirror_shutdown = 1;
3402         LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
3403                 if ((sc = gp->softc) == NULL)
3404                         continue;
3405                 /* Skip synchronization geom. */
3406                 if (gp == sc->sc_sync.ds_geom)
3407                         continue;
3408                 g_topology_unlock();
3409                 sx_xlock(&sc->sc_lock);
3410                 g_mirror_idle(sc, -1);
3411                 g_cancel_event(sc);
3412                 error = g_mirror_destroy(sc, G_MIRROR_DESTROY_DELAYED);
3413                 if (error != 0)
3414                         sx_xunlock(&sc->sc_lock);
3415                 g_topology_lock();
3416         }
3417         g_topology_unlock();
3418 }
3419
3420 static void
3421 g_mirror_init(struct g_class *mp)
3422 {
3423
3424         g_mirror_post_sync = EVENTHANDLER_REGISTER(shutdown_post_sync,
3425             g_mirror_shutdown_post_sync, mp, SHUTDOWN_PRI_FIRST);
3426         if (g_mirror_post_sync == NULL)
3427                 G_MIRROR_DEBUG(0, "Warning! Cannot register shutdown event.");
3428 }
3429
3430 static void
3431 g_mirror_fini(struct g_class *mp)
3432 {
3433
3434         if (g_mirror_post_sync != NULL)
3435                 EVENTHANDLER_DEREGISTER(shutdown_post_sync, g_mirror_post_sync);
3436 }
3437
3438 DECLARE_GEOM_CLASS(g_mirror_class, g_mirror);