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/bio.h>
  35 #include <sys/eventhandler.h>
  36 #include <sys/fail.h>
  37 #include <sys/kernel.h>
  38 #include <sys/kthread.h>
  39 #include <sys/limits.h>
  40 #include <sys/lock.h>
  41 #include <sys/malloc.h>
  42 #include <sys/mutex.h>
  43 #include <sys/proc.h>
  44 #include <sys/sbuf.h>
  45 #include <sys/sched.h>
  46 #include <sys/sx.h>
  47 #include <sys/sysctl.h>
  48
  49 #include <geom/geom.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_reinit(const struct g_mirror_disk *disk,
 114     struct bio *bp, off_t offset);
 115 static void g_mirror_sync_stop(struct g_mirror_disk *disk, int type);
 116 static void g_mirror_register_request(struct g_mirror_softc *sc,
 117     struct bio *bp);
 118 static void g_mirror_sync_release(struct g_mirror_softc *sc);
 119
 120
 121 static const char *
 122 g_mirror_disk_state2str(int state)
 123 {
 124
 125         switch (state) {
 126         case G_MIRROR_DISK_STATE_NONE:
 127                 return ("NONE");
 128         case G_MIRROR_DISK_STATE_NEW:
 129                 return ("NEW");
 130         case G_MIRROR_DISK_STATE_ACTIVE:
 131                 return ("ACTIVE");
 132         case G_MIRROR_DISK_STATE_STALE:
 133                 return ("STALE");
 134         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
 135                 return ("SYNCHRONIZING");
 136         case G_MIRROR_DISK_STATE_DISCONNECTED:
 137                 return ("DISCONNECTED");
 138         case G_MIRROR_DISK_STATE_DESTROY:
 139                 return ("DESTROY");
 140         default:
 141                 return ("INVALID");
 142         }
 143 }
 144
 145 static const char *
 146 g_mirror_device_state2str(int state)
 147 {
 148
 149         switch (state) {
 150         case G_MIRROR_DEVICE_STATE_STARTING:
 151                 return ("STARTING");
 152         case G_MIRROR_DEVICE_STATE_RUNNING:
 153                 return ("RUNNING");
 154         default:
 155                 return ("INVALID");
 156         }
 157 }
 158
 159 static const char *
 160 g_mirror_get_diskname(struct g_mirror_disk *disk)
 161 {
 162
 163         if (disk->d_consumer == NULL || disk->d_consumer->provider == NULL)
 164                 return ("[unknown]");
 165         return (disk->d_name);
 166 }
 167
 168 /*
 169  * --- Events handling functions ---
 170  * Events in geom_mirror are used to maintain disks and device status
 171  * from one thread to simplify locking.
 172  */
 173 static void
 174 g_mirror_event_free(struct g_mirror_event *ep)
 175 {
 176
 177         free(ep, M_MIRROR);
 178 }
 179
 180 int
 181 g_mirror_event_send(void *arg, int state, int flags)
 182 {
 183         struct g_mirror_softc *sc;
 184         struct g_mirror_disk *disk;
 185         struct g_mirror_event *ep;
 186         int error;
 187
 188         ep = malloc(sizeof(*ep), M_MIRROR, M_WAITOK);
 189         G_MIRROR_DEBUG(4, "%s: Sending event %p.", __func__, ep);
 190         if ((flags & G_MIRROR_EVENT_DEVICE) != 0) {
 191                 disk = NULL;
 192                 sc = arg;
 193         } else {
 194                 disk = arg;
 195                 sc = disk->d_softc;
 196         }
 197         ep->e_disk = disk;
 198         ep->e_state = state;
 199         ep->e_flags = flags;
 200         ep->e_error = 0;
 201         mtx_lock(&sc->sc_events_mtx);
 202         TAILQ_INSERT_TAIL(&sc->sc_events, ep, e_next);
 203         mtx_unlock(&sc->sc_events_mtx);
 204         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
 205         mtx_lock(&sc->sc_queue_mtx);
 206         wakeup(sc);
 207         mtx_unlock(&sc->sc_queue_mtx);
 208         if ((flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 209                 return (0);
 210         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, ep);
 211         sx_xunlock(&sc->sc_lock);
 212         while ((ep->e_flags & G_MIRROR_EVENT_DONE) == 0) {
 213                 mtx_lock(&sc->sc_events_mtx);
 214                 MSLEEP(ep, &sc->sc_events_mtx, PRIBIO | PDROP, "m:event",
 215                     hz * 5);
 216         }
 217         error = ep->e_error;
 218         g_mirror_event_free(ep);
 219         sx_xlock(&sc->sc_lock);
 220         return (error);
 221 }
 222
 223 static struct g_mirror_event *
 224 g_mirror_event_first(struct g_mirror_softc *sc)
 225 {
 226         struct g_mirror_event *ep;
 227
 228         mtx_lock(&sc->sc_events_mtx);
 229         ep = TAILQ_FIRST(&sc->sc_events);
 230         mtx_unlock(&sc->sc_events_mtx);
 231         return (ep);
 232 }
 233
 234 static void
 235 g_mirror_event_remove(struct g_mirror_softc *sc, struct g_mirror_event *ep)
 236 {
 237
 238         mtx_lock(&sc->sc_events_mtx);
 239         TAILQ_REMOVE(&sc->sc_events, ep, e_next);
 240         mtx_unlock(&sc->sc_events_mtx);
 241 }
 242
 243 static void
 244 g_mirror_event_cancel(struct g_mirror_disk *disk)
 245 {
 246         struct g_mirror_softc *sc;
 247         struct g_mirror_event *ep, *tmpep;
 248
 249         sc = disk->d_softc;
 250         sx_assert(&sc->sc_lock, SX_XLOCKED);
 251
 252         mtx_lock(&sc->sc_events_mtx);
 253         TAILQ_FOREACH_SAFE(ep, &sc->sc_events, e_next, tmpep) {
 254                 if ((ep->e_flags & G_MIRROR_EVENT_DEVICE) != 0)
 255                         continue;
 256                 if (ep->e_disk != disk)
 257                         continue;
 258                 TAILQ_REMOVE(&sc->sc_events, ep, e_next);
 259                 if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 260                         g_mirror_event_free(ep);
 261                 else {
 262                         ep->e_error = ECANCELED;
 263                         wakeup(ep);
 264                 }
 265         }
 266         mtx_unlock(&sc->sc_events_mtx);
 267 }
 268
 269 /*
 270  * Return the number of disks in given state.
 271  * If state is equal to -1, count all connected disks.
 272  */
 273 u_int
 274 g_mirror_ndisks(struct g_mirror_softc *sc, int state)
 275 {
 276         struct g_mirror_disk *disk;
 277         u_int n = 0;
 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, 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         g_topology_lock();
 496         LIST_REMOVE(disk, d_next);
 497         g_topology_unlock();
 498         g_mirror_event_cancel(disk);
 499         if (sc->sc_hint == disk)
 500                 sc->sc_hint = NULL;
 501         switch (disk->d_state) {
 502         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
 503                 g_mirror_sync_stop(disk, 1);
 504                 /* FALLTHROUGH */
 505         case G_MIRROR_DISK_STATE_NEW:
 506         case G_MIRROR_DISK_STATE_STALE:
 507         case G_MIRROR_DISK_STATE_ACTIVE:
 508                 g_topology_lock();
 509                 g_mirror_disconnect_consumer(sc, disk->d_consumer);
 510                 g_topology_unlock();
 511                 free(disk, M_MIRROR);
 512                 break;
 513         default:
 514                 KASSERT(0 == 1, ("Wrong disk state (%s, %s).",
 515                     g_mirror_get_diskname(disk),
 516                     g_mirror_disk_state2str(disk->d_state)));
 517         }
 518 }
 519
 520 static void
 521 g_mirror_free_device(struct g_mirror_softc *sc)
 522 {
 523
 524         g_topology_assert();
 525
 526         mtx_destroy(&sc->sc_queue_mtx);
 527         mtx_destroy(&sc->sc_events_mtx);
 528         mtx_destroy(&sc->sc_done_mtx);
 529         sx_destroy(&sc->sc_lock);
 530         free(sc, M_MIRROR);
 531 }
 532
 533 static void
 534 g_mirror_providergone(struct g_provider *pp)
 535 {
 536         struct g_mirror_softc *sc = pp->private;
 537
 538         if ((--sc->sc_refcnt) == 0)
 539                 g_mirror_free_device(sc);
 540 }
 541
 542 static void
 543 g_mirror_destroy_device(struct g_mirror_softc *sc)
 544 {
 545         struct g_mirror_disk *disk;
 546         struct g_mirror_event *ep;
 547         struct g_geom *gp;
 548         struct g_consumer *cp, *tmpcp;
 549
 550         g_topology_assert_not();
 551         sx_assert(&sc->sc_lock, SX_XLOCKED);
 552
 553         gp = sc->sc_geom;
 554         if (sc->sc_provider != NULL)
 555                 g_mirror_destroy_provider(sc);
 556         for (disk = LIST_FIRST(&sc->sc_disks); disk != NULL;
 557             disk = LIST_FIRST(&sc->sc_disks)) {
 558                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
 559                 g_mirror_update_metadata(disk);
 560                 g_mirror_destroy_disk(disk);
 561         }
 562         while ((ep = g_mirror_event_first(sc)) != NULL) {
 563                 g_mirror_event_remove(sc, ep);
 564                 if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 565                         g_mirror_event_free(ep);
 566                 else {
 567                         ep->e_error = ECANCELED;
 568                         ep->e_flags |= G_MIRROR_EVENT_DONE;
 569                         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, ep);
 570                         mtx_lock(&sc->sc_events_mtx);
 571                         wakeup(ep);
 572                         mtx_unlock(&sc->sc_events_mtx);
 573                 }
 574         }
 575         callout_drain(&sc->sc_callout);
 576
 577         g_topology_lock();
 578         LIST_FOREACH_SAFE(cp, &sc->sc_sync.ds_geom->consumer, consumer, tmpcp) {
 579                 g_mirror_disconnect_consumer(sc, cp);
 580         }
 581         g_wither_geom(sc->sc_sync.ds_geom, ENXIO);
 582         G_MIRROR_DEBUG(0, "Device %s destroyed.", gp->name);
 583         g_wither_geom(gp, ENXIO);
 584         sx_xunlock(&sc->sc_lock);
 585         if ((--sc->sc_refcnt) == 0)
 586                 g_mirror_free_device(sc);
 587         g_topology_unlock();
 588 }
 589
 590 static void
 591 g_mirror_orphan(struct g_consumer *cp)
 592 {
 593         struct g_mirror_disk *disk;
 594
 595         g_topology_assert();
 596
 597         disk = cp->private;
 598         if (disk == NULL)
 599                 return;
 600         disk->d_softc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
 601         g_mirror_event_send(disk, G_MIRROR_DISK_STATE_DISCONNECTED,
 602             G_MIRROR_EVENT_DONTWAIT);
 603 }
 604
 605 /*
 606  * Function should return the next active disk on the list.
 607  * It is possible that it will be the same disk as given.
 608  * If there are no active disks on list, NULL is returned.
 609  */
 610 static __inline struct g_mirror_disk *
 611 g_mirror_find_next(struct g_mirror_softc *sc, struct g_mirror_disk *disk)
 612 {
 613         struct g_mirror_disk *dp;
 614
 615         for (dp = LIST_NEXT(disk, d_next); dp != disk;
 616             dp = LIST_NEXT(dp, d_next)) {
 617                 if (dp == NULL)
 618                         dp = LIST_FIRST(&sc->sc_disks);
 619                 if (dp->d_state == G_MIRROR_DISK_STATE_ACTIVE)
 620                         break;
 621         }
 622         if (dp->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 623                 return (NULL);
 624         return (dp);
 625 }
 626
 627 static struct g_mirror_disk *
 628 g_mirror_get_disk(struct g_mirror_softc *sc)
 629 {
 630         struct g_mirror_disk *disk;
 631
 632         if (sc->sc_hint == NULL) {
 633                 sc->sc_hint = LIST_FIRST(&sc->sc_disks);
 634                 if (sc->sc_hint == NULL)
 635                         return (NULL);
 636         }
 637         disk = sc->sc_hint;
 638         if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE) {
 639                 disk = g_mirror_find_next(sc, disk);
 640                 if (disk == NULL)
 641                         return (NULL);
 642         }
 643         sc->sc_hint = g_mirror_find_next(sc, disk);
 644         return (disk);
 645 }
 646
 647 static int
 648 g_mirror_write_metadata(struct g_mirror_disk *disk,
 649     struct g_mirror_metadata *md)
 650 {
 651         struct g_mirror_softc *sc;
 652         struct g_consumer *cp;
 653         off_t offset, length;
 654         u_char *sector;
 655         int error = 0;
 656
 657         g_topology_assert_not();
 658         sc = disk->d_softc;
 659         sx_assert(&sc->sc_lock, SX_LOCKED);
 660
 661         cp = disk->d_consumer;
 662         KASSERT(cp != NULL, ("NULL consumer (%s).", sc->sc_name));
 663         KASSERT(cp->provider != NULL, ("NULL provider (%s).", sc->sc_name));
 664         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
 665             ("Consumer %s closed? (r%dw%de%d).", cp->provider->name, cp->acr,
 666             cp->acw, cp->ace));
 667         length = cp->provider->sectorsize;
 668         offset = cp->provider->mediasize - length;
 669         sector = malloc((size_t)length, M_MIRROR, M_WAITOK | M_ZERO);
 670         if (md != NULL &&
 671             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_WIPE) == 0) {
 672                 /*
 673                  * Handle the case, when the size of parent provider reduced.
 674                  */
 675                 if (offset < md->md_mediasize)
 676                         error = ENOSPC;
 677                 else
 678                         mirror_metadata_encode(md, sector);
 679         }
 680         KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_metadata_write, error);
 681         if (error == 0)
 682                 error = g_write_data(cp, offset, sector, length);
 683         free(sector, M_MIRROR);
 684         if (error != 0) {
 685                 if ((disk->d_flags & G_MIRROR_DISK_FLAG_BROKEN) == 0) {
 686                         disk->d_flags |= G_MIRROR_DISK_FLAG_BROKEN;
 687                         G_MIRROR_DEBUG(0, "Cannot write metadata on %s "
 688                             "(device=%s, error=%d).",
 689                             g_mirror_get_diskname(disk), sc->sc_name, error);
 690                 } else {
 691                         G_MIRROR_DEBUG(1, "Cannot write metadata on %s "
 692                             "(device=%s, error=%d).",
 693                             g_mirror_get_diskname(disk), sc->sc_name, error);
 694                 }
 695                 if (g_mirror_disconnect_on_failure &&
 696                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 1) {
 697                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
 698                         g_mirror_event_send(disk,
 699                             G_MIRROR_DISK_STATE_DISCONNECTED,
 700                             G_MIRROR_EVENT_DONTWAIT);
 701                 }
 702         }
 703         return (error);
 704 }
 705
 706 static int
 707 g_mirror_clear_metadata(struct g_mirror_disk *disk)
 708 {
 709         int error;
 710
 711         g_topology_assert_not();
 712         sx_assert(&disk->d_softc->sc_lock, SX_LOCKED);
 713
 714         if (disk->d_softc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
 715                 return (0);
 716         error = g_mirror_write_metadata(disk, NULL);
 717         if (error == 0) {
 718                 G_MIRROR_DEBUG(2, "Metadata on %s cleared.",
 719                     g_mirror_get_diskname(disk));
 720         } else {
 721                 G_MIRROR_DEBUG(0,
 722                     "Cannot clear metadata on disk %s (error=%d).",
 723                     g_mirror_get_diskname(disk), error);
 724         }
 725         return (error);
 726 }
 727
 728 void
 729 g_mirror_fill_metadata(struct g_mirror_softc *sc, struct g_mirror_disk *disk,
 730     struct g_mirror_metadata *md)
 731 {
 732
 733         strlcpy(md->md_magic, G_MIRROR_MAGIC, sizeof(md->md_magic));
 734         md->md_version = G_MIRROR_VERSION;
 735         strlcpy(md->md_name, sc->sc_name, sizeof(md->md_name));
 736         md->md_mid = sc->sc_id;
 737         md->md_all = sc->sc_ndisks;
 738         md->md_slice = sc->sc_slice;
 739         md->md_balance = sc->sc_balance;
 740         md->md_genid = sc->sc_genid;
 741         md->md_mediasize = sc->sc_mediasize;
 742         md->md_sectorsize = sc->sc_sectorsize;
 743         md->md_mflags = (sc->sc_flags & G_MIRROR_DEVICE_FLAG_MASK);
 744         bzero(md->md_provider, sizeof(md->md_provider));
 745         if (disk == NULL) {
 746                 md->md_did = arc4random();
 747                 md->md_priority = 0;
 748                 md->md_syncid = 0;
 749                 md->md_dflags = 0;
 750                 md->md_sync_offset = 0;
 751                 md->md_provsize = 0;
 752         } else {
 753                 md->md_did = disk->d_id;
 754                 md->md_priority = disk->d_priority;
 755                 md->md_syncid = disk->d_sync.ds_syncid;
 756                 md->md_dflags = (disk->d_flags & G_MIRROR_DISK_FLAG_MASK);
 757                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
 758                         md->md_sync_offset = disk->d_sync.ds_offset_done;
 759                 else
 760                         md->md_sync_offset = 0;
 761                 if ((disk->d_flags & G_MIRROR_DISK_FLAG_HARDCODED) != 0) {
 762                         strlcpy(md->md_provider,
 763                             disk->d_consumer->provider->name,
 764                             sizeof(md->md_provider));
 765                 }
 766                 md->md_provsize = disk->d_consumer->provider->mediasize;
 767         }
 768 }
 769
 770 void
 771 g_mirror_update_metadata(struct g_mirror_disk *disk)
 772 {
 773         struct g_mirror_softc *sc;
 774         struct g_mirror_metadata md;
 775         int error;
 776
 777         g_topology_assert_not();
 778         sc = disk->d_softc;
 779         sx_assert(&sc->sc_lock, SX_LOCKED);
 780
 781         if (sc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
 782                 return;
 783         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_WIPE) == 0)
 784                 g_mirror_fill_metadata(sc, disk, &md);
 785         error = g_mirror_write_metadata(disk, &md);
 786         if (error == 0) {
 787                 G_MIRROR_DEBUG(2, "Metadata on %s updated.",
 788                     g_mirror_get_diskname(disk));
 789         } else {
 790                 G_MIRROR_DEBUG(0,
 791                     "Cannot update metadata on disk %s (error=%d).",
 792                     g_mirror_get_diskname(disk), error);
 793         }
 794 }
 795
 796 static void
 797 g_mirror_bump_syncid(struct g_mirror_softc *sc)
 798 {
 799         struct g_mirror_disk *disk;
 800
 801         g_topology_assert_not();
 802         sx_assert(&sc->sc_lock, SX_XLOCKED);
 803         KASSERT(g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 0,
 804             ("%s called with no active disks (device=%s).", __func__,
 805             sc->sc_name));
 806
 807         sc->sc_syncid++;
 808         G_MIRROR_DEBUG(1, "Device %s: syncid bumped to %u.", sc->sc_name,
 809             sc->sc_syncid);
 810         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 811                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
 812                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
 813                         disk->d_sync.ds_syncid = sc->sc_syncid;
 814                         g_mirror_update_metadata(disk);
 815                 }
 816         }
 817 }
 818
 819 static void
 820 g_mirror_bump_genid(struct g_mirror_softc *sc)
 821 {
 822         struct g_mirror_disk *disk;
 823
 824         g_topology_assert_not();
 825         sx_assert(&sc->sc_lock, SX_XLOCKED);
 826         KASSERT(g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 0,
 827             ("%s called with no active disks (device=%s).", __func__,
 828             sc->sc_name));
 829
 830         sc->sc_genid++;
 831         G_MIRROR_DEBUG(1, "Device %s: genid bumped to %u.", sc->sc_name,
 832             sc->sc_genid);
 833         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 834                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
 835                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
 836                         disk->d_genid = sc->sc_genid;
 837                         g_mirror_update_metadata(disk);
 838                 }
 839         }
 840 }
 841
 842 static int
 843 g_mirror_idle(struct g_mirror_softc *sc, int acw)
 844 {
 845         struct g_mirror_disk *disk;
 846         int timeout;
 847
 848         g_topology_assert_not();
 849         sx_assert(&sc->sc_lock, SX_XLOCKED);
 850
 851         if (sc->sc_provider == NULL)
 852                 return (0);
 853         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
 854                 return (0);
 855         if (sc->sc_idle)
 856                 return (0);
 857         if (sc->sc_writes > 0)
 858                 return (0);
 859         if (acw > 0 || (acw == -1 && sc->sc_provider->acw > 0)) {
 860                 timeout = g_mirror_idletime - (time_uptime - sc->sc_last_write);
 861                 if (!g_mirror_shutdown && timeout > 0)
 862                         return (timeout);
 863         }
 864         sc->sc_idle = 1;
 865         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 866                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 867                         continue;
 868                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as clean.",
 869                     g_mirror_get_diskname(disk), sc->sc_name);
 870                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
 871                 g_mirror_update_metadata(disk);
 872         }
 873         return (0);
 874 }
 875
 876 static void
 877 g_mirror_unidle(struct g_mirror_softc *sc)
 878 {
 879         struct g_mirror_disk *disk;
 880
 881         g_topology_assert_not();
 882         sx_assert(&sc->sc_lock, SX_XLOCKED);
 883
 884         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
 885                 return;
 886         sc->sc_idle = 0;
 887         sc->sc_last_write = time_uptime;
 888         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 889                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 890                         continue;
 891                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as dirty.",
 892                     g_mirror_get_diskname(disk), sc->sc_name);
 893                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
 894                 g_mirror_update_metadata(disk);
 895         }
 896 }
 897
 898 static void
 899 g_mirror_done(struct bio *bp)
 900 {
 901         struct g_mirror_softc *sc;
 902
 903         sc = bp->bio_from->geom->softc;
 904         bp->bio_cflags = G_MIRROR_BIO_FLAG_REGULAR;
 905         mtx_lock(&sc->sc_queue_mtx);
 906         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
 907         mtx_unlock(&sc->sc_queue_mtx);
 908         wakeup(sc);
 909 }
 910
 911 static void
 912 g_mirror_regular_request_error(struct g_mirror_softc *sc,
 913     struct g_mirror_disk *disk, struct bio *bp)
 914 {
 915
 916         if (bp->bio_cmd == BIO_FLUSH && bp->bio_error == EOPNOTSUPP)
 917                 return;
 918
 919         if ((disk->d_flags & G_MIRROR_DISK_FLAG_BROKEN) == 0) {
 920                 disk->d_flags |= G_MIRROR_DISK_FLAG_BROKEN;
 921                 G_MIRROR_LOGREQ(0, bp, "Request failed (error=%d).",
 922                     bp->bio_error);
 923         } else {
 924                 G_MIRROR_LOGREQ(1, bp, "Request failed (error=%d).",
 925                     bp->bio_error);
 926         }
 927         if (g_mirror_disconnect_on_failure &&
 928             g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 1) {
 929                 if (bp->bio_error == ENXIO &&
 930                     bp->bio_cmd == BIO_READ)
 931                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
 932                 else if (bp->bio_error == ENXIO)
 933                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID_NOW;
 934                 else
 935                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
 936                 g_mirror_event_send(disk, G_MIRROR_DISK_STATE_DISCONNECTED,
 937                     G_MIRROR_EVENT_DONTWAIT);
 938         }
 939 }
 940
 941 static void
 942 g_mirror_regular_request(struct g_mirror_softc *sc, struct bio *bp)
 943 {
 944         struct g_mirror_disk *disk;
 945         struct bio *pbp;
 946
 947         g_topology_assert_not();
 948         KASSERT(sc->sc_provider == bp->bio_parent->bio_to,
 949             ("regular request %p with unexpected origin", bp));
 950
 951         pbp = bp->bio_parent;
 952         bp->bio_from->index--;
 953         if (bp->bio_cmd == BIO_WRITE || bp->bio_cmd == BIO_DELETE)
 954                 sc->sc_writes--;
 955         disk = bp->bio_from->private;
 956         if (disk == NULL) {
 957                 g_topology_lock();
 958                 g_mirror_kill_consumer(sc, bp->bio_from);
 959                 g_topology_unlock();
 960         }
 961
 962         switch (bp->bio_cmd) {
 963         case BIO_READ:
 964                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_read,
 965                     bp->bio_error);
 966                 break;
 967         case BIO_WRITE:
 968                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_write,
 969                     bp->bio_error);
 970                 break;
 971         case BIO_DELETE:
 972                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_delete,
 973                     bp->bio_error);
 974                 break;
 975         case BIO_FLUSH:
 976                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_flush,
 977                     bp->bio_error);
 978                 break;
 979         }
 980
 981         pbp->bio_inbed++;
 982         KASSERT(pbp->bio_inbed <= pbp->bio_children,
 983             ("bio_inbed (%u) is bigger than bio_children (%u).", pbp->bio_inbed,
 984             pbp->bio_children));
 985         if (bp->bio_error == 0 && pbp->bio_error == 0) {
 986                 G_MIRROR_LOGREQ(3, bp, "Request delivered.");
 987                 g_destroy_bio(bp);
 988                 if (pbp->bio_children == pbp->bio_inbed) {
 989                         G_MIRROR_LOGREQ(3, pbp, "Request delivered.");
 990                         pbp->bio_completed = pbp->bio_length;
 991                         if (pbp->bio_cmd == BIO_WRITE ||
 992                             pbp->bio_cmd == BIO_DELETE) {
 993                                 TAILQ_REMOVE(&sc->sc_inflight, pbp, bio_queue);
 994                                 /* Release delayed sync requests if possible. */
 995                                 g_mirror_sync_release(sc);
 996                         }
 997                         g_io_deliver(pbp, pbp->bio_error);
 998                 }
 999                 return;
1000         } else if (bp->bio_error != 0) {
1001                 if (pbp->bio_error == 0)
1002                         pbp->bio_error = bp->bio_error;
1003                 if (disk != NULL)
1004                         g_mirror_regular_request_error(sc, disk, bp);
1005                 switch (pbp->bio_cmd) {
1006                 case BIO_DELETE:
1007                 case BIO_WRITE:
1008                 case BIO_FLUSH:
1009                         pbp->bio_inbed--;
1010                         pbp->bio_children--;
1011                         break;
1012                 }
1013         }
1014         g_destroy_bio(bp);
1015
1016         switch (pbp->bio_cmd) {
1017         case BIO_READ:
1018                 if (pbp->bio_inbed < pbp->bio_children)
1019                         break;
1020                 if (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 1)
1021                         g_io_deliver(pbp, pbp->bio_error);
1022                 else {
1023                         pbp->bio_error = 0;
1024                         mtx_lock(&sc->sc_queue_mtx);
1025                         TAILQ_INSERT_TAIL(&sc->sc_queue, pbp, bio_queue);
1026                         mtx_unlock(&sc->sc_queue_mtx);
1027                         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
1028                         wakeup(sc);
1029                 }
1030                 break;
1031         case BIO_DELETE:
1032         case BIO_WRITE:
1033         case BIO_FLUSH:
1034                 if (pbp->bio_children == 0) {
1035                         /*
1036                          * All requests failed.
1037                          */
1038                 } else if (pbp->bio_inbed < pbp->bio_children) {
1039                         /* Do nothing. */
1040                         break;
1041                 } else if (pbp->bio_children == pbp->bio_inbed) {
1042                         /* Some requests succeeded. */
1043                         pbp->bio_error = 0;
1044                         pbp->bio_completed = pbp->bio_length;
1045                 }
1046                 if (pbp->bio_cmd == BIO_WRITE || pbp->bio_cmd == BIO_DELETE) {
1047                         TAILQ_REMOVE(&sc->sc_inflight, pbp, bio_queue);
1048                         /* Release delayed sync requests if possible. */
1049                         g_mirror_sync_release(sc);
1050                 }
1051                 g_io_deliver(pbp, pbp->bio_error);
1052                 break;
1053         default:
1054                 KASSERT(1 == 0, ("Invalid request: %u.", pbp->bio_cmd));
1055                 break;
1056         }
1057 }
1058
1059 static void
1060 g_mirror_sync_done(struct bio *bp)
1061 {
1062         struct g_mirror_softc *sc;
1063
1064         G_MIRROR_LOGREQ(3, bp, "Synchronization request delivered.");
1065         sc = bp->bio_from->geom->softc;
1066         bp->bio_cflags = G_MIRROR_BIO_FLAG_SYNC;
1067         mtx_lock(&sc->sc_queue_mtx);
1068         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
1069         mtx_unlock(&sc->sc_queue_mtx);
1070         wakeup(sc);
1071 }
1072
1073 static void
1074 g_mirror_candelete(struct bio *bp)
1075 {
1076         struct g_mirror_softc *sc;
1077         struct g_mirror_disk *disk;
1078         int *val;
1079
1080         sc = bp->bio_to->private;
1081         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1082                 if (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE)
1083                         break;
1084         }
1085         val = (int *)bp->bio_data;
1086         *val = (disk != NULL);
1087         g_io_deliver(bp, 0);
1088 }
1089
1090 static void
1091 g_mirror_kernel_dump(struct bio *bp)
1092 {
1093         struct g_mirror_softc *sc;
1094         struct g_mirror_disk *disk;
1095         struct bio *cbp;
1096         struct g_kerneldump *gkd;
1097
1098         /*
1099          * We configure dumping to the first component, because this component
1100          * will be used for reading with 'prefer' balance algorithm.
1101          * If the component with the highest priority is currently disconnected
1102          * we will not be able to read the dump after the reboot if it will be
1103          * connected and synchronized later. Can we do something better?
1104          */
1105         sc = bp->bio_to->private;
1106         disk = LIST_FIRST(&sc->sc_disks);
1107
1108         gkd = (struct g_kerneldump *)bp->bio_data;
1109         if (gkd->length > bp->bio_to->mediasize)
1110                 gkd->length = bp->bio_to->mediasize;
1111         cbp = g_clone_bio(bp);
1112         if (cbp == NULL) {
1113                 g_io_deliver(bp, ENOMEM);
1114                 return;
1115         }
1116         cbp->bio_done = g_std_done;
1117         g_io_request(cbp, disk->d_consumer);
1118         G_MIRROR_DEBUG(1, "Kernel dump will go to %s.",
1119             g_mirror_get_diskname(disk));
1120 }
1121
1122 static void
1123 g_mirror_start(struct bio *bp)
1124 {
1125         struct g_mirror_softc *sc;
1126
1127         sc = bp->bio_to->private;
1128         /*
1129          * If sc == NULL or there are no valid disks, provider's error
1130          * should be set and g_mirror_start() should not be called at all.
1131          */
1132         KASSERT(sc != NULL && sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
1133             ("Provider's error should be set (error=%d)(mirror=%s).",
1134             bp->bio_to->error, bp->bio_to->name));
1135         G_MIRROR_LOGREQ(3, bp, "Request received.");
1136
1137         switch (bp->bio_cmd) {
1138         case BIO_READ:
1139         case BIO_WRITE:
1140         case BIO_DELETE:
1141         case BIO_FLUSH:
1142                 break;
1143         case BIO_GETATTR:
1144                 if (!strcmp(bp->bio_attribute, "GEOM::candelete")) {
1145                         g_mirror_candelete(bp);
1146                         return;
1147                 } else if (strcmp("GEOM::kerneldump", bp->bio_attribute) == 0) {
1148                         g_mirror_kernel_dump(bp);
1149                         return;
1150                 }
1151                 /* FALLTHROUGH */
1152         default:
1153                 g_io_deliver(bp, EOPNOTSUPP);
1154                 return;
1155         }
1156         mtx_lock(&sc->sc_queue_mtx);
1157         if (bp->bio_to->error != 0) {
1158                 mtx_unlock(&sc->sc_queue_mtx);
1159                 g_io_deliver(bp, bp->bio_to->error);
1160                 return;
1161         }
1162         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
1163         mtx_unlock(&sc->sc_queue_mtx);
1164         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
1165         wakeup(sc);
1166 }
1167
1168 /*
1169  * Return TRUE if the given request is colliding with a in-progress
1170  * synchronization request.
1171  */
1172 static bool
1173 g_mirror_sync_collision(struct g_mirror_softc *sc, struct bio *bp)
1174 {
1175         struct g_mirror_disk *disk;
1176         struct bio *sbp;
1177         off_t rstart, rend, sstart, send;
1178         u_int i;
1179
1180         if (sc->sc_sync.ds_ndisks == 0)
1181                 return (false);
1182         rstart = bp->bio_offset;
1183         rend = bp->bio_offset + bp->bio_length;
1184         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1185                 if (disk->d_state != G_MIRROR_DISK_STATE_SYNCHRONIZING)
1186                         continue;
1187                 for (i = 0; i < g_mirror_syncreqs; i++) {
1188                         sbp = disk->d_sync.ds_bios[i];
1189                         if (sbp == NULL)
1190                                 continue;
1191                         sstart = sbp->bio_offset;
1192                         send = sbp->bio_offset + sbp->bio_length;
1193                         if (rend > sstart && rstart < send)
1194                                 return (true);
1195                 }
1196         }
1197         return (false);
1198 }
1199
1200 /*
1201  * Return TRUE if the given sync request is colliding with a in-progress regular
1202  * request.
1203  */
1204 static bool
1205 g_mirror_regular_collision(struct g_mirror_softc *sc, struct bio *sbp)
1206 {
1207         off_t rstart, rend, sstart, send;
1208         struct bio *bp;
1209
1210         if (sc->sc_sync.ds_ndisks == 0)
1211                 return (false);
1212         sstart = sbp->bio_offset;
1213         send = sbp->bio_offset + sbp->bio_length;
1214         TAILQ_FOREACH(bp, &sc->sc_inflight, bio_queue) {
1215                 rstart = bp->bio_offset;
1216                 rend = bp->bio_offset + bp->bio_length;
1217                 if (rend > sstart && rstart < send)
1218                         return (true);
1219         }
1220         return (false);
1221 }
1222
1223 /*
1224  * Puts regular request onto delayed queue.
1225  */
1226 static void
1227 g_mirror_regular_delay(struct g_mirror_softc *sc, struct bio *bp)
1228 {
1229
1230         G_MIRROR_LOGREQ(2, bp, "Delaying request.");
1231         TAILQ_INSERT_TAIL(&sc->sc_regular_delayed, bp, bio_queue);
1232 }
1233
1234 /*
1235  * Puts synchronization request onto delayed queue.
1236  */
1237 static void
1238 g_mirror_sync_delay(struct g_mirror_softc *sc, struct bio *bp)
1239 {
1240
1241         G_MIRROR_LOGREQ(2, bp, "Delaying synchronization request.");
1242         TAILQ_INSERT_TAIL(&sc->sc_sync_delayed, bp, bio_queue);
1243 }
1244
1245 /*
1246  * Requeue delayed regular requests.
1247  */
1248 static void
1249 g_mirror_regular_release(struct g_mirror_softc *sc)
1250 {
1251         struct bio *bp;
1252
1253         if ((bp = TAILQ_FIRST(&sc->sc_regular_delayed)) == NULL)
1254                 return;
1255         if (g_mirror_sync_collision(sc, bp))
1256                 return;
1257
1258         G_MIRROR_DEBUG(2, "Requeuing regular requests after collision.");
1259         mtx_lock(&sc->sc_queue_mtx);
1260         TAILQ_CONCAT(&sc->sc_regular_delayed, &sc->sc_queue, bio_queue);
1261         TAILQ_SWAP(&sc->sc_regular_delayed, &sc->sc_queue, bio, bio_queue);
1262         mtx_unlock(&sc->sc_queue_mtx);
1263 }
1264
1265 /*
1266  * Releases delayed sync requests which don't collide anymore with regular
1267  * requests.
1268  */
1269 static void
1270 g_mirror_sync_release(struct g_mirror_softc *sc)
1271 {
1272         struct bio *bp, *bp2;
1273
1274         TAILQ_FOREACH_SAFE(bp, &sc->sc_sync_delayed, bio_queue, bp2) {
1275                 if (g_mirror_regular_collision(sc, bp))
1276                         continue;
1277                 TAILQ_REMOVE(&sc->sc_sync_delayed, bp, bio_queue);
1278                 G_MIRROR_LOGREQ(2, bp,
1279                     "Releasing delayed synchronization request.");
1280                 g_io_request(bp, bp->bio_from);
1281         }
1282 }
1283
1284 /*
1285  * Free a synchronization request and clear its slot in the array.
1286  */
1287 static void
1288 g_mirror_sync_request_free(struct g_mirror_disk *disk, struct bio *bp)
1289 {
1290         int idx;
1291
1292         if (disk != NULL && disk->d_sync.ds_bios != NULL) {
1293                 idx = (int)(uintptr_t)bp->bio_caller1;
1294                 KASSERT(disk->d_sync.ds_bios[idx] == bp,
1295                     ("unexpected sync BIO at %p:%d", disk, idx));
1296                 disk->d_sync.ds_bios[idx] = NULL;
1297         }
1298         free(bp->bio_data, M_MIRROR);
1299         g_destroy_bio(bp);
1300 }
1301
1302 /*
1303  * Handle synchronization requests.
1304  * Every synchronization request is a two-step process: first, a read request is
1305  * sent to the mirror provider via the sync consumer. If that request completes
1306  * successfully, it is converted to a write and sent to the disk being
1307  * synchronized. If the write also completes successfully, the synchronization
1308  * offset is advanced and a new read request is submitted.
1309  */
1310 static void
1311 g_mirror_sync_request(struct g_mirror_softc *sc, struct bio *bp)
1312 {
1313         struct g_mirror_disk *disk;
1314         struct g_mirror_disk_sync *sync;
1315
1316         KASSERT((bp->bio_cmd == BIO_READ &&
1317             bp->bio_from->geom == sc->sc_sync.ds_geom) ||
1318             (bp->bio_cmd == BIO_WRITE && bp->bio_from->geom == sc->sc_geom),
1319             ("Sync BIO %p with unexpected origin", bp));
1320
1321         bp->bio_from->index--;
1322         disk = bp->bio_from->private;
1323         if (disk == NULL) {
1324                 sx_xunlock(&sc->sc_lock); /* Avoid recursion on sc_lock. */
1325                 g_topology_lock();
1326                 g_mirror_kill_consumer(sc, bp->bio_from);
1327                 g_topology_unlock();
1328                 g_mirror_sync_request_free(NULL, bp);
1329                 sx_xlock(&sc->sc_lock);
1330                 return;
1331         }
1332
1333         sync = &disk->d_sync;
1334
1335         /*
1336          * Synchronization request.
1337          */
1338         switch (bp->bio_cmd) {
1339         case BIO_READ: {
1340                 struct g_consumer *cp;
1341
1342                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_sync_request_read,
1343                     bp->bio_error);
1344
1345                 if (bp->bio_error != 0) {
1346                         G_MIRROR_LOGREQ(0, bp,
1347                             "Synchronization request failed (error=%d).",
1348                             bp->bio_error);
1349
1350                         /*
1351                          * The read error will trigger a syncid bump, so there's
1352                          * no need to do that here.
1353                          *
1354                          * The read error handling for regular requests will
1355                          * retry the read from all active mirrors before passing
1356                          * the error back up, so there's no need to retry here.
1357                          */
1358                         g_mirror_sync_request_free(disk, bp);
1359                         g_mirror_event_send(disk,
1360                             G_MIRROR_DISK_STATE_DISCONNECTED,
1361                             G_MIRROR_EVENT_DONTWAIT);
1362                         return;
1363                 }
1364                 G_MIRROR_LOGREQ(3, bp,
1365                     "Synchronization request half-finished.");
1366                 bp->bio_cmd = BIO_WRITE;
1367                 bp->bio_cflags = 0;
1368                 cp = disk->d_consumer;
1369                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1370                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1371                     cp->acr, cp->acw, cp->ace));
1372                 cp->index++;
1373                 g_io_request(bp, cp);
1374                 return;
1375         }
1376         case BIO_WRITE: {
1377                 off_t offset;
1378                 int i;
1379
1380                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_sync_request_write,
1381                     bp->bio_error);
1382
1383                 if (bp->bio_error != 0) {
1384                         G_MIRROR_LOGREQ(0, bp,
1385                             "Synchronization request failed (error=%d).",
1386                             bp->bio_error);
1387                         g_mirror_sync_request_free(disk, bp);
1388                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
1389                         g_mirror_event_send(disk,
1390                             G_MIRROR_DISK_STATE_DISCONNECTED,
1391                             G_MIRROR_EVENT_DONTWAIT);
1392                         return;
1393                 }
1394                 G_MIRROR_LOGREQ(3, bp, "Synchronization request finished.");
1395                 if (sync->ds_offset >= sc->sc_mediasize ||
1396                     sync->ds_consumer == NULL ||
1397                     (sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1398                         /* Don't send more synchronization requests. */
1399                         sync->ds_inflight--;
1400                         g_mirror_sync_request_free(disk, bp);
1401                         if (sync->ds_inflight > 0)
1402                                 return;
1403                         if (sync->ds_consumer == NULL ||
1404                             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1405                                 return;
1406                         }
1407                         /* Disk up-to-date, activate it. */
1408                         g_mirror_event_send(disk, G_MIRROR_DISK_STATE_ACTIVE,
1409                             G_MIRROR_EVENT_DONTWAIT);
1410                         return;
1411                 }
1412
1413                 /* Send next synchronization request. */
1414                 g_mirror_sync_reinit(disk, bp, sync->ds_offset);
1415                 sync->ds_offset += bp->bio_length;
1416
1417                 G_MIRROR_LOGREQ(3, bp, "Sending synchronization request.");
1418                 sync->ds_consumer->index++;
1419
1420                 /*
1421                  * Delay the request if it is colliding with a regular request.
1422                  */
1423                 if (g_mirror_regular_collision(sc, bp))
1424                         g_mirror_sync_delay(sc, bp);
1425                 else
1426                         g_io_request(bp, sync->ds_consumer);
1427
1428                 /* Requeue delayed requests if possible. */
1429                 g_mirror_regular_release(sc);
1430
1431                 /* Find the smallest offset */
1432                 offset = sc->sc_mediasize;
1433                 for (i = 0; i < g_mirror_syncreqs; i++) {
1434                         bp = sync->ds_bios[i];
1435                         if (bp != NULL && bp->bio_offset < offset)
1436                                 offset = bp->bio_offset;
1437                 }
1438                 if (g_mirror_sync_period > 0 &&
1439                     time_uptime - sync->ds_update_ts > g_mirror_sync_period) {
1440                         sync->ds_offset_done = offset;
1441                         g_mirror_update_metadata(disk);
1442                         sync->ds_update_ts = time_uptime;
1443                 }
1444                 return;
1445         }
1446         default:
1447                 panic("Invalid I/O request %p", bp);
1448         }
1449 }
1450
1451 static void
1452 g_mirror_request_prefer(struct g_mirror_softc *sc, struct bio *bp)
1453 {
1454         struct g_mirror_disk *disk;
1455         struct g_consumer *cp;
1456         struct bio *cbp;
1457
1458         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1459                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE)
1460                         break;
1461         }
1462         if (disk == NULL) {
1463                 if (bp->bio_error == 0)
1464                         bp->bio_error = ENXIO;
1465                 g_io_deliver(bp, bp->bio_error);
1466                 return;
1467         }
1468         cbp = g_clone_bio(bp);
1469         if (cbp == NULL) {
1470                 if (bp->bio_error == 0)
1471                         bp->bio_error = ENOMEM;
1472                 g_io_deliver(bp, bp->bio_error);
1473                 return;
1474         }
1475         /*
1476          * Fill in the component buf structure.
1477          */
1478         cp = disk->d_consumer;
1479         cbp->bio_done = g_mirror_done;
1480         cbp->bio_to = cp->provider;
1481         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1482         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1483             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1484             cp->acw, cp->ace));
1485         cp->index++;
1486         g_io_request(cbp, cp);
1487 }
1488
1489 static void
1490 g_mirror_request_round_robin(struct g_mirror_softc *sc, struct bio *bp)
1491 {
1492         struct g_mirror_disk *disk;
1493         struct g_consumer *cp;
1494         struct bio *cbp;
1495
1496         disk = g_mirror_get_disk(sc);
1497         if (disk == NULL) {
1498                 if (bp->bio_error == 0)
1499                         bp->bio_error = ENXIO;
1500                 g_io_deliver(bp, bp->bio_error);
1501                 return;
1502         }
1503         cbp = g_clone_bio(bp);
1504         if (cbp == NULL) {
1505                 if (bp->bio_error == 0)
1506                         bp->bio_error = ENOMEM;
1507                 g_io_deliver(bp, bp->bio_error);
1508                 return;
1509         }
1510         /*
1511          * Fill in the component buf structure.
1512          */
1513         cp = disk->d_consumer;
1514         cbp->bio_done = g_mirror_done;
1515         cbp->bio_to = cp->provider;
1516         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1517         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1518             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1519             cp->acw, cp->ace));
1520         cp->index++;
1521         g_io_request(cbp, cp);
1522 }
1523
1524 #define TRACK_SIZE  (1 * 1024 * 1024)
1525 #define LOAD_SCALE      256
1526 #define ABS(x)          (((x) >= 0) ? (x) : (-(x)))
1527
1528 static void
1529 g_mirror_request_load(struct g_mirror_softc *sc, struct bio *bp)
1530 {
1531         struct g_mirror_disk *disk, *dp;
1532         struct g_consumer *cp;
1533         struct bio *cbp;
1534         int prio, best;
1535
1536         /* Find a disk with the smallest load. */
1537         disk = NULL;
1538         best = INT_MAX;
1539         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
1540                 if (dp->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1541                         continue;
1542                 prio = dp->load;
1543                 /* If disk head is precisely in position - highly prefer it. */
1544                 if (dp->d_last_offset == bp->bio_offset)
1545                         prio -= 2 * LOAD_SCALE;
1546                 else
1547                 /* If disk head is close to position - prefer it. */
1548                 if (ABS(dp->d_last_offset - bp->bio_offset) < TRACK_SIZE)
1549                         prio -= 1 * LOAD_SCALE;
1550                 if (prio <= best) {
1551                         disk = dp;
1552                         best = prio;
1553                 }
1554         }
1555         KASSERT(disk != NULL, ("NULL disk for %s.", sc->sc_name));
1556         cbp = g_clone_bio(bp);
1557         if (cbp == NULL) {
1558                 if (bp->bio_error == 0)
1559                         bp->bio_error = ENOMEM;
1560                 g_io_deliver(bp, bp->bio_error);
1561                 return;
1562         }
1563         /*
1564          * Fill in the component buf structure.
1565          */
1566         cp = disk->d_consumer;
1567         cbp->bio_done = g_mirror_done;
1568         cbp->bio_to = cp->provider;
1569         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1570         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1571             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1572             cp->acw, cp->ace));
1573         cp->index++;
1574         /* Remember last head position */
1575         disk->d_last_offset = bp->bio_offset + bp->bio_length;
1576         /* Update loads. */
1577         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
1578                 dp->load = (dp->d_consumer->index * LOAD_SCALE +
1579                     dp->load * 7) / 8;
1580         }
1581         g_io_request(cbp, cp);
1582 }
1583
1584 static void
1585 g_mirror_request_split(struct g_mirror_softc *sc, struct bio *bp)
1586 {
1587         struct bio_queue queue;
1588         struct g_mirror_disk *disk;
1589         struct g_consumer *cp;
1590         struct bio *cbp;
1591         off_t left, mod, offset, slice;
1592         u_char *data;
1593         u_int ndisks;
1594
1595         if (bp->bio_length <= sc->sc_slice) {
1596                 g_mirror_request_round_robin(sc, bp);
1597                 return;
1598         }
1599         ndisks = g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE);
1600         slice = bp->bio_length / ndisks;
1601         mod = slice % sc->sc_provider->sectorsize;
1602         if (mod != 0)
1603                 slice += sc->sc_provider->sectorsize - mod;
1604         /*
1605          * Allocate all bios before sending any request, so we can
1606          * return ENOMEM in nice and clean way.
1607          */
1608         left = bp->bio_length;
1609         offset = bp->bio_offset;
1610         data = bp->bio_data;
1611         TAILQ_INIT(&queue);
1612         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1613                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1614                         continue;
1615                 cbp = g_clone_bio(bp);
1616                 if (cbp == NULL) {
1617                         while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1618                                 TAILQ_REMOVE(&queue, cbp, bio_queue);
1619                                 g_destroy_bio(cbp);
1620                         }
1621                         if (bp->bio_error == 0)
1622                                 bp->bio_error = ENOMEM;
1623                         g_io_deliver(bp, bp->bio_error);
1624                         return;
1625                 }
1626                 TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1627                 cbp->bio_done = g_mirror_done;
1628                 cbp->bio_caller1 = disk;
1629                 cbp->bio_to = disk->d_consumer->provider;
1630                 cbp->bio_offset = offset;
1631                 cbp->bio_data = data;
1632                 cbp->bio_length = MIN(left, slice);
1633                 left -= cbp->bio_length;
1634                 if (left == 0)
1635                         break;
1636                 offset += cbp->bio_length;
1637                 data += cbp->bio_length;
1638         }
1639         while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1640                 TAILQ_REMOVE(&queue, cbp, bio_queue);
1641                 G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1642                 disk = cbp->bio_caller1;
1643                 cbp->bio_caller1 = NULL;
1644                 cp = disk->d_consumer;
1645                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1646                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1647                     cp->acr, cp->acw, cp->ace));
1648                 disk->d_consumer->index++;
1649                 g_io_request(cbp, disk->d_consumer);
1650         }
1651 }
1652
1653 static void
1654 g_mirror_register_request(struct g_mirror_softc *sc, struct bio *bp)
1655 {
1656         struct bio_queue queue;
1657         struct bio *cbp;
1658         struct g_consumer *cp;
1659         struct g_mirror_disk *disk;
1660
1661         sx_assert(&sc->sc_lock, SA_XLOCKED);
1662
1663         /*
1664          * To avoid ordering issues, if a write is deferred because of a
1665          * collision with a sync request, all I/O is deferred until that
1666          * write is initiated.
1667          */
1668         if (bp->bio_from->geom != sc->sc_sync.ds_geom &&
1669             !TAILQ_EMPTY(&sc->sc_regular_delayed)) {
1670                 g_mirror_regular_delay(sc, bp);
1671                 return;
1672         }
1673
1674         switch (bp->bio_cmd) {
1675         case BIO_READ:
1676                 switch (sc->sc_balance) {
1677                 case G_MIRROR_BALANCE_LOAD:
1678                         g_mirror_request_load(sc, bp);
1679                         break;
1680                 case G_MIRROR_BALANCE_PREFER:
1681                         g_mirror_request_prefer(sc, bp);
1682                         break;
1683                 case G_MIRROR_BALANCE_ROUND_ROBIN:
1684                         g_mirror_request_round_robin(sc, bp);
1685                         break;
1686                 case G_MIRROR_BALANCE_SPLIT:
1687                         g_mirror_request_split(sc, bp);
1688                         break;
1689                 }
1690                 return;
1691         case BIO_WRITE:
1692         case BIO_DELETE:
1693                 /*
1694                  * Delay the request if it is colliding with a synchronization
1695                  * request.
1696                  */
1697                 if (g_mirror_sync_collision(sc, bp)) {
1698                         g_mirror_regular_delay(sc, bp);
1699                         return;
1700                 }
1701
1702                 if (sc->sc_idle)
1703                         g_mirror_unidle(sc);
1704                 else
1705                         sc->sc_last_write = time_uptime;
1706
1707                 /*
1708                  * Bump syncid on first write.
1709                  */
1710                 if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID) != 0) {
1711                         sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID;
1712                         g_mirror_bump_syncid(sc);
1713                 }
1714
1715                 /*
1716                  * Allocate all bios before sending any request, so we can
1717                  * return ENOMEM in nice and clean way.
1718                  */
1719                 TAILQ_INIT(&queue);
1720                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1721                         switch (disk->d_state) {
1722                         case G_MIRROR_DISK_STATE_ACTIVE:
1723                                 break;
1724                         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
1725                                 if (bp->bio_offset >= disk->d_sync.ds_offset)
1726                                         continue;
1727                                 break;
1728                         default:
1729                                 continue;
1730                         }
1731                         if (bp->bio_cmd == BIO_DELETE &&
1732                             (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE) == 0)
1733                                 continue;
1734                         cbp = g_clone_bio(bp);
1735                         if (cbp == NULL) {
1736                                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1737                                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1738                                         g_destroy_bio(cbp);
1739                                 }
1740                                 if (bp->bio_error == 0)
1741                                         bp->bio_error = ENOMEM;
1742                                 g_io_deliver(bp, bp->bio_error);
1743                                 return;
1744                         }
1745                         TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1746                         cbp->bio_done = g_mirror_done;
1747                         cp = disk->d_consumer;
1748                         cbp->bio_caller1 = cp;
1749                         cbp->bio_to = cp->provider;
1750                         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1751                             ("Consumer %s not opened (r%dw%de%d).",
1752                             cp->provider->name, cp->acr, cp->acw, cp->ace));
1753                 }
1754                 if (TAILQ_EMPTY(&queue)) {
1755                         KASSERT(bp->bio_cmd == BIO_DELETE,
1756                             ("No consumers for regular request %p", bp));
1757                         g_io_deliver(bp, EOPNOTSUPP);
1758                         return;
1759                 }
1760                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1761                         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1762                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1763                         cp = cbp->bio_caller1;
1764                         cbp->bio_caller1 = NULL;
1765                         cp->index++;
1766                         sc->sc_writes++;
1767                         g_io_request(cbp, cp);
1768                 }
1769                 /*
1770                  * Put request onto inflight queue, so we can check if new
1771                  * synchronization requests don't collide with it.
1772                  */
1773                 TAILQ_INSERT_TAIL(&sc->sc_inflight, bp, bio_queue);
1774                 return;
1775         case BIO_FLUSH:
1776                 TAILQ_INIT(&queue);
1777                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1778                         if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1779                                 continue;
1780                         cbp = g_clone_bio(bp);
1781                         if (cbp == NULL) {
1782                                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1783                                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1784                                         g_destroy_bio(cbp);
1785                                 }
1786                                 if (bp->bio_error == 0)
1787                                         bp->bio_error = ENOMEM;
1788                                 g_io_deliver(bp, bp->bio_error);
1789                                 return;
1790                         }
1791                         TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1792                         cbp->bio_done = g_mirror_done;
1793                         cbp->bio_caller1 = disk;
1794                         cbp->bio_to = disk->d_consumer->provider;
1795                 }
1796                 KASSERT(!TAILQ_EMPTY(&queue),
1797                     ("No consumers for regular request %p", bp));
1798                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1799                         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1800                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1801                         disk = cbp->bio_caller1;
1802                         cbp->bio_caller1 = NULL;
1803                         cp = disk->d_consumer;
1804                         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1805                             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1806                             cp->acr, cp->acw, cp->ace));
1807                         cp->index++;
1808                         g_io_request(cbp, cp);
1809                 }
1810                 break;
1811         default:
1812                 KASSERT(1 == 0, ("Invalid command here: %u (device=%s)",
1813                     bp->bio_cmd, sc->sc_name));
1814                 break;
1815         }
1816 }
1817
1818 static int
1819 g_mirror_can_destroy(struct g_mirror_softc *sc)
1820 {
1821         struct g_geom *gp;
1822         struct g_consumer *cp;
1823
1824         g_topology_assert();
1825         gp = sc->sc_geom;
1826         if (gp->softc == NULL)
1827                 return (1);
1828         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_TASTING) != 0)
1829                 return (0);
1830         LIST_FOREACH(cp, &gp->consumer, consumer) {
1831                 if (g_mirror_is_busy(sc, cp))
1832                         return (0);
1833         }
1834         gp = sc->sc_sync.ds_geom;
1835         LIST_FOREACH(cp, &gp->consumer, consumer) {
1836                 if (g_mirror_is_busy(sc, cp))
1837                         return (0);
1838         }
1839         G_MIRROR_DEBUG(2, "No I/O requests for %s, it can be destroyed.",
1840             sc->sc_name);
1841         return (1);
1842 }
1843
1844 static int
1845 g_mirror_try_destroy(struct g_mirror_softc *sc)
1846 {
1847
1848         if (sc->sc_rootmount != NULL) {
1849                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p", __LINE__,
1850                     sc->sc_rootmount);
1851                 root_mount_rel(sc->sc_rootmount);
1852                 sc->sc_rootmount = NULL;
1853         }
1854         g_topology_lock();
1855         if (!g_mirror_can_destroy(sc)) {
1856                 g_topology_unlock();
1857                 return (0);
1858         }
1859         sc->sc_geom->softc = NULL;
1860         sc->sc_sync.ds_geom->softc = NULL;
1861         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DRAIN) != 0) {
1862                 g_topology_unlock();
1863                 G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__,
1864                     &sc->sc_worker);
1865                 /* Unlock sc_lock here, as it can be destroyed after wakeup. */
1866                 sx_xunlock(&sc->sc_lock);
1867                 wakeup(&sc->sc_worker);
1868                 sc->sc_worker = NULL;
1869         } else {
1870                 g_topology_unlock();
1871                 g_mirror_destroy_device(sc);
1872         }
1873         return (1);
1874 }
1875
1876 /*
1877  * Worker thread.
1878  */
1879 static void
1880 g_mirror_worker(void *arg)
1881 {
1882         struct g_mirror_softc *sc;
1883         struct g_mirror_event *ep;
1884         struct bio *bp;
1885         int timeout;
1886
1887         sc = arg;
1888         thread_lock(curthread);
1889         sched_prio(curthread, PRIBIO);
1890         thread_unlock(curthread);
1891
1892         sx_xlock(&sc->sc_lock);
1893         for (;;) {
1894                 G_MIRROR_DEBUG(5, "%s: Let's see...", __func__);
1895                 /*
1896                  * First take a look at events.
1897                  * This is important to handle events before any I/O requests.
1898                  */
1899                 ep = g_mirror_event_first(sc);
1900                 if (ep != NULL) {
1901                         g_mirror_event_remove(sc, ep);
1902                         if ((ep->e_flags & G_MIRROR_EVENT_DEVICE) != 0) {
1903                                 /* Update only device status. */
1904                                 G_MIRROR_DEBUG(3,
1905                                     "Running event for device %s.",
1906                                     sc->sc_name);
1907                                 ep->e_error = 0;
1908                                 g_mirror_update_device(sc, true);
1909                         } else {
1910                                 /* Update disk status. */
1911                                 G_MIRROR_DEBUG(3, "Running event for disk %s.",
1912                                      g_mirror_get_diskname(ep->e_disk));
1913                                 ep->e_error = g_mirror_update_disk(ep->e_disk,
1914                                     ep->e_state);
1915                                 if (ep->e_error == 0)
1916                                         g_mirror_update_device(sc, false);
1917                         }
1918                         if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0) {
1919                                 KASSERT(ep->e_error == 0,
1920                                     ("Error cannot be handled."));
1921                                 g_mirror_event_free(ep);
1922                         } else {
1923                                 ep->e_flags |= G_MIRROR_EVENT_DONE;
1924                                 G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__,
1925                                     ep);
1926                                 mtx_lock(&sc->sc_events_mtx);
1927                                 wakeup(ep);
1928                                 mtx_unlock(&sc->sc_events_mtx);
1929                         }
1930                         if ((sc->sc_flags &
1931                             G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1932                                 if (g_mirror_try_destroy(sc)) {
1933                                         curthread->td_pflags &= ~TDP_GEOM;
1934                                         G_MIRROR_DEBUG(1, "Thread exiting.");
1935                                         kproc_exit(0);
1936                                 }
1937                         }
1938                         G_MIRROR_DEBUG(5, "%s: I'm here 1.", __func__);
1939                         continue;
1940                 }
1941
1942                 /*
1943                  * Check if we can mark array as CLEAN and if we can't take
1944                  * how much seconds should we wait.
1945                  */
1946                 timeout = g_mirror_idle(sc, -1);
1947
1948                 /*
1949                  * Handle I/O requests.
1950                  */
1951                 mtx_lock(&sc->sc_queue_mtx);
1952                 bp = TAILQ_FIRST(&sc->sc_queue);
1953                 if (bp != NULL)
1954                         TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue);
1955                 else {
1956                         if ((sc->sc_flags &
1957                             G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1958                                 mtx_unlock(&sc->sc_queue_mtx);
1959                                 if (g_mirror_try_destroy(sc)) {
1960                                         curthread->td_pflags &= ~TDP_GEOM;
1961                                         G_MIRROR_DEBUG(1, "Thread exiting.");
1962                                         kproc_exit(0);
1963                                 }
1964                                 mtx_lock(&sc->sc_queue_mtx);
1965                                 if (!TAILQ_EMPTY(&sc->sc_queue)) {
1966                                         mtx_unlock(&sc->sc_queue_mtx);
1967                                         continue;
1968                                 }
1969                         }
1970                         if (g_mirror_event_first(sc) != NULL) {
1971                                 mtx_unlock(&sc->sc_queue_mtx);
1972                                 continue;
1973                         }
1974                         sx_xunlock(&sc->sc_lock);
1975                         MSLEEP(sc, &sc->sc_queue_mtx, PRIBIO | PDROP, "m:w1",
1976                             timeout * hz);
1977                         sx_xlock(&sc->sc_lock);
1978                         G_MIRROR_DEBUG(5, "%s: I'm here 4.", __func__);
1979                         continue;
1980                 }
1981                 mtx_unlock(&sc->sc_queue_mtx);
1982
1983                 if (bp->bio_from->geom == sc->sc_sync.ds_geom &&
1984                     (bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0) {
1985                         /*
1986                          * Handle completion of the first half (the read) of a
1987                          * block synchronization operation.
1988                          */
1989                         g_mirror_sync_request(sc, bp);
1990                 } else if (bp->bio_to != sc->sc_provider) {
1991                         if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_REGULAR) != 0)
1992                                 /*
1993                                  * Handle completion of a regular I/O request.
1994                                  */
1995                                 g_mirror_regular_request(sc, bp);
1996                         else if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0)
1997                                 /*
1998                                  * Handle completion of the second half (the
1999                                  * write) of a block synchronization operation.
2000                                  */
2001                                 g_mirror_sync_request(sc, bp);
2002                         else {
2003                                 KASSERT(0,
2004                                     ("Invalid request cflags=0x%hx to=%s.",
2005                                     bp->bio_cflags, bp->bio_to->name));
2006                         }
2007                 } else {
2008                         /*
2009                          * Initiate an I/O request.
2010                          */
2011                         g_mirror_register_request(sc, bp);
2012                 }
2013                 G_MIRROR_DEBUG(5, "%s: I'm here 9.", __func__);
2014         }
2015 }
2016
2017 static void
2018 g_mirror_update_idle(struct g_mirror_softc *sc, struct g_mirror_disk *disk)
2019 {
2020
2021         sx_assert(&sc->sc_lock, SX_LOCKED);
2022
2023         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
2024                 return;
2025         if (!sc->sc_idle && (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) == 0) {
2026                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as dirty.",
2027                     g_mirror_get_diskname(disk), sc->sc_name);
2028                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
2029         } else if (sc->sc_idle &&
2030             (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) != 0) {
2031                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as clean.",
2032                     g_mirror_get_diskname(disk), sc->sc_name);
2033                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2034         }
2035 }
2036
2037 static void
2038 g_mirror_sync_reinit(const struct g_mirror_disk *disk, struct bio *bp,
2039     off_t offset)
2040 {
2041         void *data;
2042         int idx;
2043
2044         data = bp->bio_data;
2045         idx = (int)(uintptr_t)bp->bio_caller1;
2046         g_reset_bio(bp);
2047
2048         bp->bio_cmd = BIO_READ;
2049         bp->bio_data = data;
2050         bp->bio_done = g_mirror_sync_done;
2051         bp->bio_from = disk->d_sync.ds_consumer;
2052         bp->bio_to = disk->d_softc->sc_provider;
2053         bp->bio_caller1 = (void *)(uintptr_t)idx;
2054         bp->bio_offset = offset;
2055         bp->bio_length = MIN(MAXPHYS,
2056             disk->d_softc->sc_mediasize - bp->bio_offset);
2057 }
2058
2059 static void
2060 g_mirror_sync_start(struct g_mirror_disk *disk)
2061 {
2062         struct g_mirror_softc *sc;
2063         struct g_mirror_disk_sync *sync;
2064         struct g_consumer *cp;
2065         struct bio *bp;
2066         int error, i;
2067
2068         g_topology_assert_not();
2069         sc = disk->d_softc;
2070         sync = &disk->d_sync;
2071         sx_assert(&sc->sc_lock, SX_LOCKED);
2072
2073         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2074             ("Disk %s is not marked for synchronization.",
2075             g_mirror_get_diskname(disk)));
2076         KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2077             ("Device not in RUNNING state (%s, %u).", sc->sc_name,
2078             sc->sc_state));
2079
2080         sx_xunlock(&sc->sc_lock);
2081         g_topology_lock();
2082         cp = g_new_consumer(sc->sc_sync.ds_geom);
2083         cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
2084         error = g_attach(cp, sc->sc_provider);
2085         KASSERT(error == 0,
2086             ("Cannot attach to %s (error=%d).", sc->sc_name, error));
2087         error = g_access(cp, 1, 0, 0);
2088         KASSERT(error == 0, ("Cannot open %s (error=%d).", sc->sc_name, error));
2089         g_topology_unlock();
2090         sx_xlock(&sc->sc_lock);
2091
2092         G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s.", sc->sc_name,
2093             g_mirror_get_diskname(disk));
2094         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) == 0)
2095                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
2096         KASSERT(sync->ds_consumer == NULL,
2097             ("Sync consumer already exists (device=%s, disk=%s).",
2098             sc->sc_name, g_mirror_get_diskname(disk)));
2099
2100         sync->ds_consumer = cp;
2101         sync->ds_consumer->private = disk;
2102         sync->ds_consumer->index = 0;
2103
2104         /*
2105          * Allocate memory for synchronization bios and initialize them.
2106          */
2107         sync->ds_bios = malloc(sizeof(struct bio *) * g_mirror_syncreqs,
2108             M_MIRROR, M_WAITOK);
2109         for (i = 0; i < g_mirror_syncreqs; i++) {
2110                 bp = g_alloc_bio();
2111                 sync->ds_bios[i] = bp;
2112
2113                 bp->bio_data = malloc(MAXPHYS, M_MIRROR, M_WAITOK);
2114                 bp->bio_caller1 = (void *)(uintptr_t)i;
2115                 g_mirror_sync_reinit(disk, bp, sync->ds_offset);
2116                 sync->ds_offset += bp->bio_length;
2117         }
2118
2119         /* Increase the number of disks in SYNCHRONIZING state. */
2120         sc->sc_sync.ds_ndisks++;
2121         /* Set the number of in-flight synchronization requests. */
2122         sync->ds_inflight = g_mirror_syncreqs;
2123
2124         /*
2125          * Fire off first synchronization requests.
2126          */
2127         for (i = 0; i < g_mirror_syncreqs; i++) {
2128                 bp = sync->ds_bios[i];
2129                 G_MIRROR_LOGREQ(3, bp, "Sending synchronization request.");
2130                 sync->ds_consumer->index++;
2131                 /*
2132                  * Delay the request if it is colliding with a regular request.
2133                  */
2134                 if (g_mirror_regular_collision(sc, bp))
2135                         g_mirror_sync_delay(sc, bp);
2136                 else
2137                         g_io_request(bp, sync->ds_consumer);
2138         }
2139 }
2140
2141 /*
2142  * Stop synchronization process.
2143  * type: 0 - synchronization finished
2144  *       1 - synchronization stopped
2145  */
2146 static void
2147 g_mirror_sync_stop(struct g_mirror_disk *disk, int type)
2148 {
2149         struct g_mirror_softc *sc;
2150         struct g_consumer *cp;
2151
2152         g_topology_assert_not();
2153         sc = disk->d_softc;
2154         sx_assert(&sc->sc_lock, SX_LOCKED);
2155
2156         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2157             ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2158             g_mirror_disk_state2str(disk->d_state)));
2159         if (disk->d_sync.ds_consumer == NULL)
2160                 return;
2161
2162         if (type == 0) {
2163                 G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s finished.",
2164                     sc->sc_name, g_mirror_get_diskname(disk));
2165         } else /* if (type == 1) */ {
2166                 G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s stopped.",
2167                     sc->sc_name, g_mirror_get_diskname(disk));
2168         }
2169         g_mirror_regular_release(sc);
2170         free(disk->d_sync.ds_bios, M_MIRROR);
2171         disk->d_sync.ds_bios = NULL;
2172         cp = disk->d_sync.ds_consumer;
2173         disk->d_sync.ds_consumer = NULL;
2174         disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2175         sc->sc_sync.ds_ndisks--;
2176         sx_xunlock(&sc->sc_lock); /* Avoid recursion on sc_lock. */
2177         g_topology_lock();
2178         g_mirror_kill_consumer(sc, cp);
2179         g_topology_unlock();
2180         sx_xlock(&sc->sc_lock);
2181 }
2182
2183 static void
2184 g_mirror_launch_provider(struct g_mirror_softc *sc)
2185 {
2186         struct g_mirror_disk *disk;
2187         struct g_provider *pp, *dp;
2188
2189         sx_assert(&sc->sc_lock, SX_LOCKED);
2190
2191         g_topology_lock();
2192         pp = g_new_providerf(sc->sc_geom, "mirror/%s", sc->sc_name);
2193         pp->flags |= G_PF_DIRECT_RECEIVE;
2194         pp->mediasize = sc->sc_mediasize;
2195         pp->sectorsize = sc->sc_sectorsize;
2196         pp->stripesize = 0;
2197         pp->stripeoffset = 0;
2198
2199         /* Splitting of unmapped BIO's could work but isn't implemented now */
2200         if (sc->sc_balance != G_MIRROR_BALANCE_SPLIT)
2201                 pp->flags |= G_PF_ACCEPT_UNMAPPED;
2202
2203         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2204                 if (disk->d_consumer && disk->d_consumer->provider) {
2205                         dp = disk->d_consumer->provider;
2206                         if (dp->stripesize > pp->stripesize) {
2207                                 pp->stripesize = dp->stripesize;
2208                                 pp->stripeoffset = dp->stripeoffset;
2209                         }
2210                         /* A provider underneath us doesn't support unmapped */
2211                         if ((dp->flags & G_PF_ACCEPT_UNMAPPED) == 0) {
2212                                 G_MIRROR_DEBUG(0, "Cancelling unmapped "
2213                                     "because of %s.", dp->name);
2214                                 pp->flags &= ~G_PF_ACCEPT_UNMAPPED;
2215                         }
2216                 }
2217         }
2218         pp->private = sc;
2219         sc->sc_refcnt++;
2220         sc->sc_provider = pp;
2221         g_error_provider(pp, 0);
2222         g_topology_unlock();
2223         G_MIRROR_DEBUG(0, "Device %s launched (%u/%u).", pp->name,
2224             g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE), sc->sc_ndisks);
2225         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2226                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
2227                         g_mirror_sync_start(disk);
2228         }
2229 }
2230
2231 static void
2232 g_mirror_destroy_provider(struct g_mirror_softc *sc)
2233 {
2234         struct g_mirror_disk *disk;
2235         struct bio *bp;
2236
2237         g_topology_assert_not();
2238         KASSERT(sc->sc_provider != NULL, ("NULL provider (device=%s).",
2239             sc->sc_name));
2240
2241         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2242                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
2243                         g_mirror_sync_stop(disk, 1);
2244         }
2245
2246         g_topology_lock();
2247         g_error_provider(sc->sc_provider, ENXIO);
2248         mtx_lock(&sc->sc_queue_mtx);
2249         while ((bp = TAILQ_FIRST(&sc->sc_queue)) != NULL) {
2250                 TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue);
2251                 /*
2252                  * Abort any pending I/O that wasn't generated by us.
2253                  * Synchronization requests and requests destined for individual
2254                  * mirror components can be destroyed immediately.
2255                  */
2256                 if (bp->bio_to == sc->sc_provider &&
2257                     bp->bio_from->geom != sc->sc_sync.ds_geom) {
2258                         g_io_deliver(bp, ENXIO);
2259                 } else {
2260                         if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0)
2261                                 free(bp->bio_data, M_MIRROR);
2262                         g_destroy_bio(bp);
2263                 }
2264         }
2265         mtx_unlock(&sc->sc_queue_mtx);
2266         g_wither_provider(sc->sc_provider, ENXIO);
2267         sc->sc_provider = NULL;
2268         G_MIRROR_DEBUG(0, "Device %s: provider destroyed.", sc->sc_name);
2269         g_topology_unlock();
2270 }
2271
2272 static void
2273 g_mirror_go(void *arg)
2274 {
2275         struct g_mirror_softc *sc;
2276
2277         sc = arg;
2278         G_MIRROR_DEBUG(0, "Force device %s start due to timeout.", sc->sc_name);
2279         g_mirror_event_send(sc, 0,
2280             G_MIRROR_EVENT_DONTWAIT | G_MIRROR_EVENT_DEVICE);
2281 }
2282
2283 static u_int
2284 g_mirror_determine_state(struct g_mirror_disk *disk)
2285 {
2286         struct g_mirror_softc *sc;
2287         u_int state;
2288
2289         sc = disk->d_softc;
2290         if (sc->sc_syncid == disk->d_sync.ds_syncid) {
2291                 if ((disk->d_flags &
2292                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) == 0 &&
2293                     (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 0 ||
2294                      (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) == 0)) {
2295                         /* Disk does not need synchronization. */
2296                         state = G_MIRROR_DISK_STATE_ACTIVE;
2297                 } else {
2298                         if ((sc->sc_flags &
2299                              G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) == 0 ||
2300                             (disk->d_flags &
2301                              G_MIRROR_DISK_FLAG_FORCE_SYNC) != 0) {
2302                                 /*
2303                                  * We can start synchronization from
2304                                  * the stored offset.
2305                                  */
2306                                 state = G_MIRROR_DISK_STATE_SYNCHRONIZING;
2307                         } else {
2308                                 state = G_MIRROR_DISK_STATE_STALE;
2309                         }
2310                 }
2311         } else if (disk->d_sync.ds_syncid < sc->sc_syncid) {
2312                 /*
2313                  * Reset all synchronization data for this disk,
2314                  * because if it even was synchronized, it was
2315                  * synchronized to disks with different syncid.
2316                  */
2317                 disk->d_flags |= G_MIRROR_DISK_FLAG_SYNCHRONIZING;
2318                 disk->d_sync.ds_offset = 0;
2319                 disk->d_sync.ds_offset_done = 0;
2320                 disk->d_sync.ds_syncid = sc->sc_syncid;
2321                 if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) == 0 ||
2322                     (disk->d_flags & G_MIRROR_DISK_FLAG_FORCE_SYNC) != 0) {
2323                         state = G_MIRROR_DISK_STATE_SYNCHRONIZING;
2324                 } else {
2325                         state = G_MIRROR_DISK_STATE_STALE;
2326                 }
2327         } else /* if (sc->sc_syncid < disk->d_sync.ds_syncid) */ {
2328                 /*
2329                  * Not good, NOT GOOD!
2330                  * It means that mirror was started on stale disks
2331                  * and more fresh disk just arrive.
2332                  * If there were writes, mirror is broken, sorry.
2333                  * I think the best choice here is don't touch
2334                  * this disk and inform the user loudly.
2335                  */
2336                 G_MIRROR_DEBUG(0, "Device %s was started before the freshest "
2337                     "disk (%s) arrives!! It will not be connected to the "
2338                     "running device.", sc->sc_name,
2339                     g_mirror_get_diskname(disk));
2340                 g_mirror_destroy_disk(disk);
2341                 state = G_MIRROR_DISK_STATE_NONE;
2342                 /* Return immediately, because disk was destroyed. */
2343                 return (state);
2344         }
2345         G_MIRROR_DEBUG(3, "State for %s disk: %s.",
2346             g_mirror_get_diskname(disk), g_mirror_disk_state2str(state));
2347         return (state);
2348 }
2349
2350 /*
2351  * Update device state.
2352  */
2353 static void
2354 g_mirror_update_device(struct g_mirror_softc *sc, bool force)
2355 {
2356         struct g_mirror_disk *disk;
2357         u_int state;
2358
2359         sx_assert(&sc->sc_lock, SX_XLOCKED);
2360
2361         switch (sc->sc_state) {
2362         case G_MIRROR_DEVICE_STATE_STARTING:
2363             {
2364                 struct g_mirror_disk *pdisk, *tdisk;
2365                 u_int dirty, ndisks, genid, syncid;
2366                 bool broken;
2367
2368                 KASSERT(sc->sc_provider == NULL,
2369                     ("Non-NULL provider in STARTING state (%s).", sc->sc_name));
2370                 /*
2371                  * Are we ready? We are, if all disks are connected or
2372                  * if we have any disks and 'force' is true.
2373                  */
2374                 ndisks = g_mirror_ndisks(sc, -1);
2375                 if (sc->sc_ndisks == ndisks || (force && ndisks > 0)) {
2376                         ;
2377                 } else if (ndisks == 0) {
2378                         /*
2379                          * Disks went down in starting phase, so destroy
2380                          * device.
2381                          */
2382                         callout_drain(&sc->sc_callout);
2383                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2384                         G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p", __LINE__,
2385                             sc->sc_rootmount);
2386                         root_mount_rel(sc->sc_rootmount);
2387                         sc->sc_rootmount = NULL;
2388                         return;
2389                 } else {
2390                         return;
2391                 }
2392
2393                 /*
2394                  * Activate all disks with the biggest syncid.
2395                  */
2396                 if (force) {
2397                         /*
2398                          * If 'force' is true, we have been called due to
2399                          * timeout, so don't bother canceling timeout.
2400                          */
2401                         ndisks = 0;
2402                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2403                                 if ((disk->d_flags &
2404                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) == 0) {
2405                                         ndisks++;
2406                                 }
2407                         }
2408                         if (ndisks == 0) {
2409                                 /* No valid disks found, destroy device. */
2410                                 sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2411                                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p",
2412                                     __LINE__, sc->sc_rootmount);
2413                                 root_mount_rel(sc->sc_rootmount);
2414                                 sc->sc_rootmount = NULL;
2415                                 return;
2416                         }
2417                 } else {
2418                         /* Cancel timeout. */
2419                         callout_drain(&sc->sc_callout);
2420                 }
2421
2422                 /*
2423                  * Find the biggest genid.
2424                  */
2425                 genid = 0;
2426                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2427                         if (disk->d_genid > genid)
2428                                 genid = disk->d_genid;
2429                 }
2430                 sc->sc_genid = genid;
2431                 /*
2432                  * Remove all disks without the biggest genid.
2433                  */
2434                 broken = false;
2435                 LIST_FOREACH_SAFE(disk, &sc->sc_disks, d_next, tdisk) {
2436                         if (disk->d_genid < genid) {
2437                                 G_MIRROR_DEBUG(0,
2438                                     "Component %s (device %s) broken, skipping.",
2439                                     g_mirror_get_diskname(disk), sc->sc_name);
2440                                 g_mirror_destroy_disk(disk);
2441                                 /*
2442                                  * Bump the syncid in case we discover a healthy
2443                                  * replacement disk after starting the mirror.
2444                                  */
2445                                 broken = true;
2446                         }
2447                 }
2448
2449                 /*
2450                  * Find the biggest syncid.
2451                  */
2452                 syncid = 0;
2453                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2454                         if (disk->d_sync.ds_syncid > syncid)
2455                                 syncid = disk->d_sync.ds_syncid;
2456                 }
2457
2458                 /*
2459                  * Here we need to look for dirty disks and if all disks
2460                  * with the biggest syncid are dirty, we have to choose
2461                  * one with the biggest priority and rebuild the rest.
2462                  */
2463                 /*
2464                  * Find the number of dirty disks with the biggest syncid.
2465                  * Find the number of disks with the biggest syncid.
2466                  * While here, find a disk with the biggest priority.
2467                  */
2468                 dirty = ndisks = 0;
2469                 pdisk = NULL;
2470                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2471                         if (disk->d_sync.ds_syncid != syncid)
2472                                 continue;
2473                         if ((disk->d_flags &
2474                             G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2475                                 continue;
2476                         }
2477                         ndisks++;
2478                         if ((disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) != 0) {
2479                                 dirty++;
2480                                 if (pdisk == NULL ||
2481                                     pdisk->d_priority < disk->d_priority) {
2482                                         pdisk = disk;
2483                                 }
2484                         }
2485                 }
2486                 if (dirty == 0) {
2487                         /* No dirty disks at all, great. */
2488                 } else if (dirty == ndisks) {
2489                         /*
2490                          * Force synchronization for all dirty disks except one
2491                          * with the biggest priority.
2492                          */
2493                         KASSERT(pdisk != NULL, ("pdisk == NULL"));
2494                         G_MIRROR_DEBUG(1, "Using disk %s (device %s) as a "
2495                             "master disk for synchronization.",
2496                             g_mirror_get_diskname(pdisk), sc->sc_name);
2497                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2498                                 if (disk->d_sync.ds_syncid != syncid)
2499                                         continue;
2500                                 if ((disk->d_flags &
2501                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2502                                         continue;
2503                                 }
2504                                 KASSERT((disk->d_flags &
2505                                     G_MIRROR_DISK_FLAG_DIRTY) != 0,
2506                                     ("Disk %s isn't marked as dirty.",
2507                                     g_mirror_get_diskname(disk)));
2508                                 /* Skip the disk with the biggest priority. */
2509                                 if (disk == pdisk)
2510                                         continue;
2511                                 disk->d_sync.ds_syncid = 0;
2512                         }
2513                 } else if (dirty < ndisks) {
2514                         /*
2515                          * Force synchronization for all dirty disks.
2516                          * We have some non-dirty disks.
2517                          */
2518                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2519                                 if (disk->d_sync.ds_syncid != syncid)
2520                                         continue;
2521                                 if ((disk->d_flags &
2522                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2523                                         continue;
2524                                 }
2525                                 if ((disk->d_flags &
2526                                     G_MIRROR_DISK_FLAG_DIRTY) == 0) {
2527                                         continue;
2528                                 }
2529                                 disk->d_sync.ds_syncid = 0;
2530                         }
2531                 }
2532
2533                 /* Reset hint. */
2534                 sc->sc_hint = NULL;
2535                 sc->sc_syncid = syncid;
2536                 if (force || broken) {
2537                         /* Remember to bump syncid on first write. */
2538                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2539                 }
2540                 state = G_MIRROR_DEVICE_STATE_RUNNING;
2541                 G_MIRROR_DEBUG(1, "Device %s state changed from %s to %s.",
2542                     sc->sc_name, g_mirror_device_state2str(sc->sc_state),
2543                     g_mirror_device_state2str(state));
2544                 sc->sc_state = state;
2545                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2546                         state = g_mirror_determine_state(disk);
2547                         g_mirror_event_send(disk, state,
2548                             G_MIRROR_EVENT_DONTWAIT);
2549                         if (state == G_MIRROR_DISK_STATE_STALE)
2550                                 sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2551                 }
2552                 break;
2553             }
2554         case G_MIRROR_DEVICE_STATE_RUNNING:
2555                 if (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 0 &&
2556                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_NEW) == 0) {
2557                         /*
2558                          * No usable disks, so destroy the device.
2559                          */
2560                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2561                         break;
2562                 } else if (g_mirror_ndisks(sc,
2563                     G_MIRROR_DISK_STATE_ACTIVE) > 0 &&
2564                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_NEW) == 0) {
2565                         /*
2566                          * We have active disks, launch provider if it doesn't
2567                          * exist.
2568                          */
2569                         if (sc->sc_provider == NULL)
2570                                 g_mirror_launch_provider(sc);
2571                         if (sc->sc_rootmount != NULL) {
2572                                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p",
2573                                     __LINE__, sc->sc_rootmount);
2574                                 root_mount_rel(sc->sc_rootmount);
2575                                 sc->sc_rootmount = NULL;
2576                         }
2577                 }
2578                 /*
2579                  * Genid should be bumped immediately, so do it here.
2580                  */
2581                 if ((sc->sc_bump_id & G_MIRROR_BUMP_GENID) != 0) {
2582                         sc->sc_bump_id &= ~G_MIRROR_BUMP_GENID;
2583                         g_mirror_bump_genid(sc);
2584                 }
2585                 if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID_NOW) != 0) {
2586                         sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID_NOW;
2587                         g_mirror_bump_syncid(sc);
2588                 }
2589                 break;
2590         default:
2591                 KASSERT(1 == 0, ("Wrong device state (%s, %s).",
2592                     sc->sc_name, g_mirror_device_state2str(sc->sc_state)));
2593                 break;
2594         }
2595 }
2596
2597 /*
2598  * Update disk state and device state if needed.
2599  */
2600 #define DISK_STATE_CHANGED()    G_MIRROR_DEBUG(1,                       \
2601         "Disk %s state changed from %s to %s (device %s).",             \
2602         g_mirror_get_diskname(disk),                                    \
2603         g_mirror_disk_state2str(disk->d_state),                         \
2604         g_mirror_disk_state2str(state), sc->sc_name)
2605 static int
2606 g_mirror_update_disk(struct g_mirror_disk *disk, u_int state)
2607 {
2608         struct g_mirror_softc *sc;
2609
2610         sc = disk->d_softc;
2611         sx_assert(&sc->sc_lock, SX_XLOCKED);
2612
2613 again:
2614         G_MIRROR_DEBUG(3, "Changing disk %s state from %s to %s.",
2615             g_mirror_get_diskname(disk), g_mirror_disk_state2str(disk->d_state),
2616             g_mirror_disk_state2str(state));
2617         switch (state) {
2618         case G_MIRROR_DISK_STATE_NEW:
2619                 /*
2620                  * Possible scenarios:
2621                  * 1. New disk arrive.
2622                  */
2623                 /* Previous state should be NONE. */
2624                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NONE,
2625                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2626                     g_mirror_disk_state2str(disk->d_state)));
2627                 DISK_STATE_CHANGED();
2628
2629                 disk->d_state = state;
2630                 g_topology_lock();
2631                 if (LIST_EMPTY(&sc->sc_disks))
2632                         LIST_INSERT_HEAD(&sc->sc_disks, disk, d_next);
2633                 else {
2634                         struct g_mirror_disk *dp;
2635
2636                         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
2637                                 if (disk->d_priority >= dp->d_priority) {
2638                                         LIST_INSERT_BEFORE(dp, disk, d_next);
2639                                         dp = NULL;
2640                                         break;
2641                                 }
2642                                 if (LIST_NEXT(dp, d_next) == NULL)
2643                                         break;
2644                         }
2645                         if (dp != NULL)
2646                                 LIST_INSERT_AFTER(dp, disk, d_next);
2647                 }
2648                 g_topology_unlock();
2649                 G_MIRROR_DEBUG(1, "Device %s: provider %s detected.",
2650                     sc->sc_name, g_mirror_get_diskname(disk));
2651                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING)
2652                         break;
2653                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2654                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2655                     g_mirror_device_state2str(sc->sc_state),
2656                     g_mirror_get_diskname(disk),
2657                     g_mirror_disk_state2str(disk->d_state)));
2658                 state = g_mirror_determine_state(disk);
2659                 if (state != G_MIRROR_DISK_STATE_NONE)
2660                         goto again;
2661                 break;
2662         case G_MIRROR_DISK_STATE_ACTIVE:
2663                 /*
2664                  * Possible scenarios:
2665                  * 1. New disk does not need synchronization.
2666                  * 2. Synchronization process finished successfully.
2667                  */
2668                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2669                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2670                     g_mirror_device_state2str(sc->sc_state),
2671                     g_mirror_get_diskname(disk),
2672                     g_mirror_disk_state2str(disk->d_state)));
2673                 /* Previous state should be NEW or SYNCHRONIZING. */
2674                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW ||
2675                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2676                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2677                     g_mirror_disk_state2str(disk->d_state)));
2678                 DISK_STATE_CHANGED();
2679
2680                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
2681                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_SYNCHRONIZING;
2682                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_FORCE_SYNC;
2683                         g_mirror_sync_stop(disk, 0);
2684                 }
2685                 disk->d_state = state;
2686                 disk->d_sync.ds_offset = 0;
2687                 disk->d_sync.ds_offset_done = 0;
2688                 g_mirror_update_idle(sc, disk);
2689                 g_mirror_update_metadata(disk);
2690                 G_MIRROR_DEBUG(1, "Device %s: provider %s activated.",
2691                     sc->sc_name, g_mirror_get_diskname(disk));
2692                 break;
2693         case G_MIRROR_DISK_STATE_STALE:
2694                 /*
2695                  * Possible scenarios:
2696                  * 1. Stale disk was connected.
2697                  */
2698                 /* Previous state should be NEW. */
2699                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2700                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2701                     g_mirror_disk_state2str(disk->d_state)));
2702                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2703                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2704                     g_mirror_device_state2str(sc->sc_state),
2705                     g_mirror_get_diskname(disk),
2706                     g_mirror_disk_state2str(disk->d_state)));
2707                 /*
2708                  * STALE state is only possible if device is marked
2709                  * NOAUTOSYNC.
2710                  */
2711                 KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) != 0,
2712                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2713                     g_mirror_device_state2str(sc->sc_state),
2714                     g_mirror_get_diskname(disk),
2715                     g_mirror_disk_state2str(disk->d_state)));
2716                 DISK_STATE_CHANGED();
2717
2718                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2719                 disk->d_state = state;
2720                 g_mirror_update_metadata(disk);
2721                 G_MIRROR_DEBUG(0, "Device %s: provider %s is stale.",
2722                     sc->sc_name, g_mirror_get_diskname(disk));
2723                 break;
2724         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
2725                 /*
2726                  * Possible scenarios:
2727                  * 1. Disk which needs synchronization was connected.
2728                  */
2729                 /* Previous state should be NEW. */
2730                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2731                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2732                     g_mirror_disk_state2str(disk->d_state)));
2733                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2734                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2735                     g_mirror_device_state2str(sc->sc_state),
2736                     g_mirror_get_diskname(disk),
2737                     g_mirror_disk_state2str(disk->d_state)));
2738                 DISK_STATE_CHANGED();
2739
2740                 if (disk->d_state == G_MIRROR_DISK_STATE_NEW)
2741                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2742                 disk->d_state = state;
2743                 if (sc->sc_provider != NULL) {
2744                         g_mirror_sync_start(disk);
2745                         g_mirror_update_metadata(disk);
2746                 }
2747                 break;
2748         case G_MIRROR_DISK_STATE_DISCONNECTED:
2749                 /*
2750                  * Possible scenarios:
2751                  * 1. Device wasn't running yet, but disk disappear.
2752                  * 2. Disk was active and disapppear.
2753                  * 3. Disk disappear during synchronization process.
2754                  */
2755                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING) {
2756                         /*
2757                          * Previous state should be ACTIVE, STALE or
2758                          * SYNCHRONIZING.
2759                          */
2760                         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
2761                             disk->d_state == G_MIRROR_DISK_STATE_STALE ||
2762                             disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2763                             ("Wrong disk state (%s, %s).",
2764                             g_mirror_get_diskname(disk),
2765                             g_mirror_disk_state2str(disk->d_state)));
2766                 } else if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING) {
2767                         /* Previous state should be NEW. */
2768                         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2769                             ("Wrong disk state (%s, %s).",
2770                             g_mirror_get_diskname(disk),
2771                             g_mirror_disk_state2str(disk->d_state)));
2772                         /*
2773                          * Reset bumping syncid if disk disappeared in STARTING
2774                          * state.
2775                          */
2776                         if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID) != 0)
2777                                 sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID;
2778 #ifdef  INVARIANTS
2779                 } else {
2780                         KASSERT(1 == 0, ("Wrong device state (%s, %s, %s, %s).",
2781                             sc->sc_name,
2782                             g_mirror_device_state2str(sc->sc_state),
2783                             g_mirror_get_diskname(disk),
2784                             g_mirror_disk_state2str(disk->d_state)));
2785 #endif
2786                 }
2787                 DISK_STATE_CHANGED();
2788                 G_MIRROR_DEBUG(0, "Device %s: provider %s disconnected.",
2789                     sc->sc_name, g_mirror_get_diskname(disk));
2790
2791                 g_mirror_destroy_disk(disk);
2792                 break;
2793         case G_MIRROR_DISK_STATE_DESTROY:
2794             {
2795                 int error;
2796
2797                 error = g_mirror_clear_metadata(disk);
2798                 if (error != 0) {
2799                         G_MIRROR_DEBUG(0,
2800                             "Device %s: failed to clear metadata on %s: %d.",
2801                             sc->sc_name, g_mirror_get_diskname(disk), error);
2802                         break;
2803                 }
2804                 DISK_STATE_CHANGED();
2805                 G_MIRROR_DEBUG(0, "Device %s: provider %s destroyed.",
2806                     sc->sc_name, g_mirror_get_diskname(disk));
2807
2808                 g_mirror_destroy_disk(disk);
2809                 sc->sc_ndisks--;
2810                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2811                         g_mirror_update_metadata(disk);
2812                 }
2813                 break;
2814             }
2815         default:
2816                 KASSERT(1 == 0, ("Unknown state (%u).", state));
2817                 break;
2818         }
2819         return (0);
2820 }
2821 #undef  DISK_STATE_CHANGED
2822
2823 int
2824 g_mirror_read_metadata(struct g_consumer *cp, struct g_mirror_metadata *md)
2825 {
2826         struct g_provider *pp;
2827         u_char *buf;
2828         int error;
2829
2830         g_topology_assert();
2831
2832         error = g_access(cp, 1, 0, 0);
2833         if (error != 0)
2834                 return (error);
2835         pp = cp->provider;
2836         g_topology_unlock();
2837         /* Metadata are stored on last sector. */
2838         buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
2839             &error);
2840         g_topology_lock();
2841         g_access(cp, -1, 0, 0);
2842         if (buf == NULL) {
2843                 G_MIRROR_DEBUG(1, "Cannot read metadata from %s (error=%d).",
2844                     cp->provider->name, error);
2845                 return (error);
2846         }
2847
2848         /* Decode metadata. */
2849         error = mirror_metadata_decode(buf, md);
2850         g_free(buf);
2851         if (strcmp(md->md_magic, G_MIRROR_MAGIC) != 0)
2852                 return (EINVAL);
2853         if (md->md_version > G_MIRROR_VERSION) {
2854                 G_MIRROR_DEBUG(0,
2855                     "Kernel module is too old to handle metadata from %s.",
2856                     cp->provider->name);
2857                 return (EINVAL);
2858         }
2859         if (error != 0) {
2860                 G_MIRROR_DEBUG(1, "MD5 metadata hash mismatch for provider %s.",
2861                     cp->provider->name);
2862                 return (error);
2863         }
2864
2865         return (0);
2866 }
2867
2868 static int
2869 g_mirror_check_metadata(struct g_mirror_softc *sc, struct g_provider *pp,
2870     struct g_mirror_metadata *md)
2871 {
2872
2873         if (g_mirror_id2disk(sc, md->md_did) != NULL) {
2874                 G_MIRROR_DEBUG(1, "Disk %s (id=%u) already exists, skipping.",
2875                     pp->name, md->md_did);
2876                 return (EEXIST);
2877         }
2878         if (md->md_all != sc->sc_ndisks) {
2879                 G_MIRROR_DEBUG(1,
2880                     "Invalid '%s' field on disk %s (device %s), skipping.",
2881                     "md_all", pp->name, sc->sc_name);
2882                 return (EINVAL);
2883         }
2884         if (md->md_slice != sc->sc_slice) {
2885                 G_MIRROR_DEBUG(1,
2886                     "Invalid '%s' field on disk %s (device %s), skipping.",
2887                     "md_slice", pp->name, sc->sc_name);
2888                 return (EINVAL);
2889         }
2890         if (md->md_balance != sc->sc_balance) {
2891                 G_MIRROR_DEBUG(1,
2892                     "Invalid '%s' field on disk %s (device %s), skipping.",
2893                     "md_balance", pp->name, sc->sc_name);
2894                 return (EINVAL);
2895         }
2896 #if 0
2897         if (md->md_mediasize != sc->sc_mediasize) {
2898                 G_MIRROR_DEBUG(1,
2899                     "Invalid '%s' field on disk %s (device %s), skipping.",
2900                     "md_mediasize", pp->name, sc->sc_name);
2901                 return (EINVAL);
2902         }
2903 #endif
2904         if (sc->sc_mediasize > pp->mediasize) {
2905                 G_MIRROR_DEBUG(1,
2906                     "Invalid size of disk %s (device %s), skipping.", pp->name,
2907                     sc->sc_name);
2908                 return (EINVAL);
2909         }
2910         if (md->md_sectorsize != sc->sc_sectorsize) {
2911                 G_MIRROR_DEBUG(1,
2912                     "Invalid '%s' field on disk %s (device %s), skipping.",
2913                     "md_sectorsize", pp->name, sc->sc_name);
2914                 return (EINVAL);
2915         }
2916         if ((sc->sc_sectorsize % pp->sectorsize) != 0) {
2917                 G_MIRROR_DEBUG(1,
2918                     "Invalid sector size of disk %s (device %s), skipping.",
2919                     pp->name, sc->sc_name);
2920                 return (EINVAL);
2921         }
2922         if ((md->md_mflags & ~G_MIRROR_DEVICE_FLAG_MASK) != 0) {
2923                 G_MIRROR_DEBUG(1,
2924                     "Invalid device flags on disk %s (device %s), skipping.",
2925                     pp->name, sc->sc_name);
2926                 return (EINVAL);
2927         }
2928         if ((md->md_dflags & ~G_MIRROR_DISK_FLAG_MASK) != 0) {
2929                 G_MIRROR_DEBUG(1,
2930                     "Invalid disk flags on disk %s (device %s), skipping.",
2931                     pp->name, sc->sc_name);
2932                 return (EINVAL);
2933         }
2934         return (0);
2935 }
2936
2937 int
2938 g_mirror_add_disk(struct g_mirror_softc *sc, struct g_provider *pp,
2939     struct g_mirror_metadata *md)
2940 {
2941         struct g_mirror_disk *disk;
2942         int error;
2943
2944         g_topology_assert_not();
2945         G_MIRROR_DEBUG(2, "Adding disk %s.", pp->name);
2946
2947         error = g_mirror_check_metadata(sc, pp, md);
2948         if (error != 0)
2949                 return (error);
2950         if (sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING &&
2951             md->md_genid < sc->sc_genid) {
2952                 G_MIRROR_DEBUG(0, "Component %s (device %s) broken, skipping.",
2953                     pp->name, sc->sc_name);
2954                 return (EINVAL);
2955         }
2956         disk = g_mirror_init_disk(sc, pp, md, &error);
2957         if (disk == NULL)
2958                 return (error);
2959         error = g_mirror_event_send(disk, G_MIRROR_DISK_STATE_NEW,
2960             G_MIRROR_EVENT_WAIT);
2961         if (error != 0)
2962                 return (error);
2963         if (md->md_version < G_MIRROR_VERSION) {
2964                 G_MIRROR_DEBUG(0, "Upgrading metadata on %s (v%d->v%d).",
2965                     pp->name, md->md_version, G_MIRROR_VERSION);
2966                 g_mirror_update_metadata(disk);
2967         }
2968         return (0);
2969 }
2970
2971 static void
2972 g_mirror_destroy_delayed(void *arg, int flag)
2973 {
2974         struct g_mirror_softc *sc;
2975         int error;
2976
2977         if (flag == EV_CANCEL) {
2978                 G_MIRROR_DEBUG(1, "Destroying canceled.");
2979                 return;
2980         }
2981         sc = arg;
2982         g_topology_unlock();
2983         sx_xlock(&sc->sc_lock);
2984         KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) == 0,
2985             ("DESTROY flag set on %s.", sc->sc_name));
2986         KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0,
2987             ("CLOSEWAIT flag not set on %s.", sc->sc_name));
2988         G_MIRROR_DEBUG(1, "Destroying %s (delayed).", sc->sc_name);
2989         error = g_mirror_destroy(sc, G_MIRROR_DESTROY_SOFT);
2990         if (error != 0) {
2991                 G_MIRROR_DEBUG(0, "Cannot destroy %s (error=%d).",
2992                     sc->sc_name, error);
2993                 sx_xunlock(&sc->sc_lock);
2994         }
2995         g_topology_lock();
2996 }
2997
2998 static int
2999 g_mirror_access(struct g_provider *pp, int acr, int acw, int ace)
3000 {
3001         struct g_mirror_softc *sc;
3002         int error = 0;
3003
3004         g_topology_assert();
3005         G_MIRROR_DEBUG(2, "Access request for %s: r%dw%de%d.", pp->name, acr,
3006             acw, ace);
3007
3008         sc = pp->private;
3009         KASSERT(sc != NULL, ("NULL softc (provider=%s).", pp->name));
3010
3011         g_topology_unlock();
3012         sx_xlock(&sc->sc_lock);
3013         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0 ||
3014             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0 ||
3015             LIST_EMPTY(&sc->sc_disks)) {
3016                 if (acr > 0 || acw > 0 || ace > 0)
3017                         error = ENXIO;
3018                 goto end;
3019         }
3020         sc->sc_provider_open += acr + acw + ace;
3021         if (pp->acw + acw == 0)
3022                 g_mirror_idle(sc, 0);
3023         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0 &&
3024             sc->sc_provider_open == 0)
3025                 g_post_event(g_mirror_destroy_delayed, sc, M_WAITOK, sc, NULL);
3026 end:
3027         sx_xunlock(&sc->sc_lock);
3028         g_topology_lock();
3029         return (error);
3030 }
3031
3032 struct g_geom *
3033 g_mirror_create(struct g_class *mp, const struct g_mirror_metadata *md,
3034     u_int type)
3035 {
3036         struct g_mirror_softc *sc;
3037         struct g_geom *gp;
3038         int error, timeout;
3039
3040         g_topology_assert();
3041         G_MIRROR_DEBUG(1, "Creating device %s (id=%u).", md->md_name,
3042             md->md_mid);
3043
3044         /* One disk is minimum. */
3045         if (md->md_all < 1)
3046                 return (NULL);
3047         /*
3048          * Action geom.
3049          */
3050         gp = g_new_geomf(mp, "%s", md->md_name);
3051         sc = malloc(sizeof(*sc), M_MIRROR, M_WAITOK | M_ZERO);
3052         gp->start = g_mirror_start;
3053         gp->orphan = g_mirror_orphan;
3054         gp->access = g_mirror_access;
3055         gp->dumpconf = g_mirror_dumpconf;
3056
3057         sc->sc_type = type;
3058         sc->sc_id = md->md_mid;
3059         sc->sc_slice = md->md_slice;
3060         sc->sc_balance = md->md_balance;
3061         sc->sc_mediasize = md->md_mediasize;
3062         sc->sc_sectorsize = md->md_sectorsize;
3063         sc->sc_ndisks = md->md_all;
3064         sc->sc_flags = md->md_mflags;
3065         sc->sc_bump_id = 0;
3066         sc->sc_idle = 1;
3067         sc->sc_last_write = time_uptime;
3068         sc->sc_writes = 0;
3069         sc->sc_refcnt = 1;
3070         sx_init(&sc->sc_lock, "gmirror:lock");
3071         TAILQ_INIT(&sc->sc_queue);
3072         mtx_init(&sc->sc_queue_mtx, "gmirror:queue", NULL, MTX_DEF);
3073         TAILQ_INIT(&sc->sc_regular_delayed);
3074         TAILQ_INIT(&sc->sc_inflight);
3075         TAILQ_INIT(&sc->sc_sync_delayed);
3076         LIST_INIT(&sc->sc_disks);
3077         TAILQ_INIT(&sc->sc_events);
3078         mtx_init(&sc->sc_events_mtx, "gmirror:events", NULL, MTX_DEF);
3079         callout_init(&sc->sc_callout, 1);
3080         mtx_init(&sc->sc_done_mtx, "gmirror:done", NULL, MTX_DEF);
3081         sc->sc_state = G_MIRROR_DEVICE_STATE_STARTING;
3082         gp->softc = sc;
3083         sc->sc_geom = gp;
3084         sc->sc_provider = NULL;
3085         sc->sc_provider_open = 0;
3086         /*
3087          * Synchronization geom.
3088          */
3089         gp = g_new_geomf(mp, "%s.sync", md->md_name);
3090         gp->softc = sc;
3091         gp->orphan = g_mirror_orphan;
3092         sc->sc_sync.ds_geom = gp;
3093         sc->sc_sync.ds_ndisks = 0;
3094         error = kproc_create(g_mirror_worker, sc, &sc->sc_worker, 0, 0,
3095             "g_mirror %s", md->md_name);
3096         if (error != 0) {
3097                 G_MIRROR_DEBUG(1, "Cannot create kernel thread for %s.",
3098                     sc->sc_name);
3099                 g_destroy_geom(sc->sc_sync.ds_geom);
3100                 g_destroy_geom(sc->sc_geom);
3101                 g_mirror_free_device(sc);
3102                 return (NULL);
3103         }
3104
3105         G_MIRROR_DEBUG(1, "Device %s created (%u components, id=%u).",
3106             sc->sc_name, sc->sc_ndisks, sc->sc_id);
3107
3108         sc->sc_rootmount = root_mount_hold("GMIRROR");
3109         G_MIRROR_DEBUG(1, "root_mount_hold %p", sc->sc_rootmount);
3110         /*
3111          * Run timeout.
3112          */
3113         timeout = g_mirror_timeout * hz;
3114         callout_reset(&sc->sc_callout, timeout, g_mirror_go, sc);
3115         return (sc->sc_geom);
3116 }
3117
3118 int
3119 g_mirror_destroy(struct g_mirror_softc *sc, int how)
3120 {
3121         struct g_mirror_disk *disk;
3122
3123         g_topology_assert_not();
3124         sx_assert(&sc->sc_lock, SX_XLOCKED);
3125
3126         if (sc->sc_provider_open != 0) {
3127                 switch (how) {
3128                 case G_MIRROR_DESTROY_SOFT:
3129                         G_MIRROR_DEBUG(1,
3130                             "Device %s is still open (%d).", sc->sc_name,
3131                             sc->sc_provider_open);
3132                         return (EBUSY);
3133                 case G_MIRROR_DESTROY_DELAYED:
3134                         G_MIRROR_DEBUG(1,
3135                             "Device %s will be destroyed on last close.",
3136                             sc->sc_name);
3137                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
3138                                 if (disk->d_state ==
3139                                     G_MIRROR_DISK_STATE_SYNCHRONIZING) {
3140                                         g_mirror_sync_stop(disk, 1);
3141                                 }
3142                         }
3143                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_CLOSEWAIT;
3144                         return (EBUSY);
3145                 case G_MIRROR_DESTROY_HARD:
3146                         G_MIRROR_DEBUG(1, "Device %s is still open, so it "
3147                             "can't be definitely removed.", sc->sc_name);
3148                 }
3149         }
3150
3151         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
3152                 sx_xunlock(&sc->sc_lock);
3153                 return (0);
3154         }
3155         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
3156         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DRAIN;
3157         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
3158         sx_xunlock(&sc->sc_lock);
3159         mtx_lock(&sc->sc_queue_mtx);
3160         wakeup(sc);
3161         mtx_unlock(&sc->sc_queue_mtx);
3162         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, &sc->sc_worker);
3163         while (sc->sc_worker != NULL)
3164                 tsleep(&sc->sc_worker, PRIBIO, "m:destroy", hz / 5);
3165         G_MIRROR_DEBUG(4, "%s: Woken up %p.", __func__, &sc->sc_worker);
3166         sx_xlock(&sc->sc_lock);
3167         g_mirror_destroy_device(sc);
3168         return (0);
3169 }
3170
3171 static void
3172 g_mirror_taste_orphan(struct g_consumer *cp)
3173 {
3174
3175         KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
3176             cp->provider->name));
3177 }
3178
3179 static struct g_geom *
3180 g_mirror_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
3181 {
3182         struct g_mirror_metadata md;
3183         struct g_mirror_softc *sc;
3184         struct g_consumer *cp;
3185         struct g_geom *gp;
3186         int error;
3187
3188         g_topology_assert();
3189         g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
3190         G_MIRROR_DEBUG(2, "Tasting %s.", pp->name);
3191
3192         gp = g_new_geomf(mp, "mirror:taste");
3193         /*
3194          * This orphan function should be never called.
3195          */
3196         gp->orphan = g_mirror_taste_orphan;
3197         cp = g_new_consumer(gp);
3198         g_attach(cp, pp);
3199         error = g_mirror_read_metadata(cp, &md);
3200         g_detach(cp);
3201         g_destroy_consumer(cp);
3202         g_destroy_geom(gp);
3203         if (error != 0)
3204                 return (NULL);
3205         gp = NULL;
3206
3207         if (md.md_provider[0] != '\0' &&
3208             !g_compare_names(md.md_provider, pp->name))
3209                 return (NULL);
3210         if (md.md_provsize != 0 && md.md_provsize != pp->mediasize)
3211                 return (NULL);
3212         if ((md.md_dflags & G_MIRROR_DISK_FLAG_INACTIVE) != 0) {
3213                 G_MIRROR_DEBUG(0,
3214                     "Device %s: provider %s marked as inactive, skipping.",
3215                     md.md_name, pp->name);
3216                 return (NULL);
3217         }
3218         if (g_mirror_debug >= 2)
3219                 mirror_metadata_dump(&md);
3220
3221         /*
3222          * Let's check if device already exists.
3223          */
3224         sc = NULL;
3225         LIST_FOREACH(gp, &mp->geom, geom) {
3226                 sc = gp->softc;
3227                 if (sc == NULL)
3228                         continue;
3229                 if (sc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
3230                         continue;
3231                 if (sc->sc_sync.ds_geom == gp)
3232                         continue;
3233                 if (strcmp(md.md_name, sc->sc_name) != 0)
3234                         continue;
3235                 if (md.md_mid != sc->sc_id) {
3236                         G_MIRROR_DEBUG(0, "Device %s already configured.",
3237                             sc->sc_name);
3238                         return (NULL);
3239                 }
3240                 break;
3241         }
3242         if (gp == NULL) {
3243                 gp = g_mirror_create(mp, &md, G_MIRROR_TYPE_AUTOMATIC);
3244                 if (gp == NULL) {
3245                         G_MIRROR_DEBUG(0, "Cannot create device %s.",
3246                             md.md_name);
3247                         return (NULL);
3248                 }
3249                 sc = gp->softc;
3250         }
3251         G_MIRROR_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
3252         g_topology_unlock();
3253         sx_xlock(&sc->sc_lock);
3254         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_TASTING;
3255         error = g_mirror_add_disk(sc, pp, &md);
3256         if (error != 0) {
3257                 G_MIRROR_DEBUG(0, "Cannot add disk %s to %s (error=%d).",
3258                     pp->name, gp->name, error);
3259                 if (LIST_EMPTY(&sc->sc_disks)) {
3260                         g_cancel_event(sc);
3261                         g_mirror_destroy(sc, G_MIRROR_DESTROY_HARD);
3262                         g_topology_lock();
3263                         return (NULL);
3264                 }
3265                 gp = NULL;
3266         }
3267         sc->sc_flags &= ~G_MIRROR_DEVICE_FLAG_TASTING;
3268         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
3269                 g_mirror_destroy(sc, G_MIRROR_DESTROY_HARD);
3270                 g_topology_lock();
3271                 return (NULL);
3272         }
3273         sx_xunlock(&sc->sc_lock);
3274         g_topology_lock();
3275         return (gp);
3276 }
3277
3278 static void
3279 g_mirror_resize(struct g_consumer *cp)
3280 {
3281         struct g_mirror_disk *disk;
3282
3283         g_topology_assert();
3284         g_trace(G_T_TOPOLOGY, "%s(%s)", __func__, cp->provider->name);
3285
3286         disk = cp->private;
3287         if (disk == NULL)
3288                 return;
3289         g_topology_unlock();
3290         g_mirror_update_metadata(disk);
3291         g_topology_lock();
3292 }
3293
3294 static int
3295 g_mirror_destroy_geom(struct gctl_req *req __unused,
3296     struct g_class *mp __unused, struct g_geom *gp)
3297 {
3298         struct g_mirror_softc *sc;
3299         int error;
3300
3301         g_topology_unlock();
3302         sc = gp->softc;
3303         sx_xlock(&sc->sc_lock);
3304         g_cancel_event(sc);
3305         error = g_mirror_destroy(gp->softc, G_MIRROR_DESTROY_SOFT);
3306         if (error != 0)
3307                 sx_xunlock(&sc->sc_lock);
3308         g_topology_lock();
3309         return (error);
3310 }
3311
3312 static void
3313 g_mirror_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
3314     struct g_consumer *cp, struct g_provider *pp)
3315 {
3316         struct g_mirror_softc *sc;
3317
3318         g_topology_assert();
3319
3320         sc = gp->softc;
3321         if (sc == NULL)
3322                 return;
3323         /* Skip synchronization geom. */
3324         if (gp == sc->sc_sync.ds_geom)
3325                 return;
3326         if (pp != NULL) {
3327                 /* Nothing here. */
3328         } else if (cp != NULL) {
3329                 struct g_mirror_disk *disk;
3330
3331                 disk = cp->private;
3332                 if (disk == NULL)
3333                         return;
3334                 sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)disk->d_id);
3335                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
3336                         sbuf_printf(sb, "%s<Synchronized>", indent);
3337                         if (disk->d_sync.ds_offset == 0)
3338                                 sbuf_printf(sb, "0%%");
3339                         else
3340                                 sbuf_printf(sb, "%u%%",
3341                                     (u_int)((disk->d_sync.ds_offset * 100) /
3342                                     sc->sc_mediasize));
3343                         sbuf_printf(sb, "</Synchronized>\n");
3344                         if (disk->d_sync.ds_offset > 0)
3345                                 sbuf_printf(sb, "%s<BytesSynced>%jd"
3346                                     "</BytesSynced>\n", indent,
3347                                     (intmax_t)disk->d_sync.ds_offset);
3348                 }
3349                 sbuf_printf(sb, "%s<SyncID>%u</SyncID>\n", indent,
3350                     disk->d_sync.ds_syncid);
3351                 sbuf_printf(sb, "%s<GenID>%u</GenID>\n", indent,
3352                     disk->d_genid);
3353                 sbuf_printf(sb, "%s<Flags>", indent);
3354                 if (disk->d_flags == 0)
3355                         sbuf_printf(sb, "NONE");
3356                 else {
3357                         int first = 1;
3358
3359 #define ADD_FLAG(flag, name)    do {                                    \
3360         if ((disk->d_flags & (flag)) != 0) {                            \
3361                 if (!first)                                             \
3362                         sbuf_printf(sb, ", ");                          \
3363                 else                                                    \
3364                         first = 0;                                      \
3365                 sbuf_printf(sb, name);                                  \
3366         }                                                               \
3367 } while (0)
3368                         ADD_FLAG(G_MIRROR_DISK_FLAG_DIRTY, "DIRTY");
3369                         ADD_FLAG(G_MIRROR_DISK_FLAG_HARDCODED, "HARDCODED");
3370                         ADD_FLAG(G_MIRROR_DISK_FLAG_INACTIVE, "INACTIVE");
3371                         ADD_FLAG(G_MIRROR_DISK_FLAG_SYNCHRONIZING,
3372                             "SYNCHRONIZING");
3373                         ADD_FLAG(G_MIRROR_DISK_FLAG_FORCE_SYNC, "FORCE_SYNC");
3374                         ADD_FLAG(G_MIRROR_DISK_FLAG_BROKEN, "BROKEN");
3375 #undef  ADD_FLAG
3376                 }
3377                 sbuf_printf(sb, "</Flags>\n");
3378                 sbuf_printf(sb, "%s<Priority>%u</Priority>\n", indent,
3379                     disk->d_priority);
3380                 sbuf_printf(sb, "%s<State>%s</State>\n", indent,
3381                     g_mirror_disk_state2str(disk->d_state));
3382         } else {
3383                 sbuf_printf(sb, "%s<Type>", indent);
3384                 switch (sc->sc_type) {
3385                 case G_MIRROR_TYPE_AUTOMATIC:
3386                         sbuf_printf(sb, "AUTOMATIC");
3387                         break;
3388                 case G_MIRROR_TYPE_MANUAL:
3389                         sbuf_printf(sb, "MANUAL");
3390                         break;
3391                 default:
3392                         sbuf_printf(sb, "UNKNOWN");
3393                         break;
3394                 }
3395                 sbuf_printf(sb, "</Type>\n");
3396                 sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)sc->sc_id);
3397                 sbuf_printf(sb, "%s<SyncID>%u</SyncID>\n", indent, sc->sc_syncid);
3398                 sbuf_printf(sb, "%s<GenID>%u</GenID>\n", indent, sc->sc_genid);
3399                 sbuf_printf(sb, "%s<Flags>", indent);
3400                 if (sc->sc_flags == 0)
3401                         sbuf_printf(sb, "NONE");
3402                 else {
3403                         int first = 1;
3404
3405 #define ADD_FLAG(flag, name)    do {                                    \
3406         if ((sc->sc_flags & (flag)) != 0) {                             \
3407                 if (!first)                                             \
3408                         sbuf_printf(sb, ", ");                          \
3409                 else                                                    \
3410                         first = 0;                                      \
3411                 sbuf_printf(sb, name);                                  \
3412         }                                                               \
3413 } while (0)
3414                         ADD_FLAG(G_MIRROR_DEVICE_FLAG_NOFAILSYNC, "NOFAILSYNC");
3415                         ADD_FLAG(G_MIRROR_DEVICE_FLAG_NOAUTOSYNC, "NOAUTOSYNC");
3416 #undef  ADD_FLAG
3417                 }
3418                 sbuf_printf(sb, "</Flags>\n");
3419                 sbuf_printf(sb, "%s<Slice>%u</Slice>\n", indent,
3420                     (u_int)sc->sc_slice);
3421                 sbuf_printf(sb, "%s<Balance>%s</Balance>\n", indent,
3422                     balance_name(sc->sc_balance));
3423                 sbuf_printf(sb, "%s<Components>%u</Components>\n", indent,
3424                     sc->sc_ndisks);
3425                 sbuf_printf(sb, "%s<State>", indent);
3426                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING)
3427                         sbuf_printf(sb, "%s", "STARTING");
3428                 else if (sc->sc_ndisks ==
3429                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE))
3430                         sbuf_printf(sb, "%s", "COMPLETE");
3431                 else
3432                         sbuf_printf(sb, "%s", "DEGRADED");
3433                 sbuf_printf(sb, "</State>\n");
3434         }
3435 }
3436
3437 static void
3438 g_mirror_shutdown_post_sync(void *arg, int howto)
3439 {
3440         struct g_class *mp;
3441         struct g_geom *gp, *gp2;
3442         struct g_mirror_softc *sc;
3443         int error;
3444
3445         if (panicstr != NULL)
3446                 return;
3447
3448         mp = arg;
3449         g_topology_lock();
3450         g_mirror_shutdown = 1;
3451         LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
3452                 if ((sc = gp->softc) == NULL)
3453                         continue;
3454                 /* Skip synchronization geom. */
3455                 if (gp == sc->sc_sync.ds_geom)
3456                         continue;
3457                 g_topology_unlock();
3458                 sx_xlock(&sc->sc_lock);
3459                 g_mirror_idle(sc, -1);
3460                 g_cancel_event(sc);
3461                 error = g_mirror_destroy(sc, G_MIRROR_DESTROY_DELAYED);
3462                 if (error != 0)
3463                         sx_xunlock(&sc->sc_lock);
3464                 g_topology_lock();
3465         }
3466         g_topology_unlock();
3467 }
3468
3469 static void
3470 g_mirror_init(struct g_class *mp)
3471 {
3472
3473         g_mirror_post_sync = EVENTHANDLER_REGISTER(shutdown_post_sync,
3474             g_mirror_shutdown_post_sync, mp, SHUTDOWN_PRI_FIRST);
3475         if (g_mirror_post_sync == NULL)
3476                 G_MIRROR_DEBUG(0, "Warning! Cannot register shutdown event.");
3477 }
3478
3479 static void
3480 g_mirror_fini(struct g_class *mp)
3481 {
3482
3483         if (g_mirror_post_sync != NULL)
3484                 EVENTHANDLER_DEREGISTER(shutdown_post_sync, g_mirror_post_sync);
3485 }
3486
3487 DECLARE_GEOM_CLASS(g_mirror_class, g_mirror);
3488 MODULE_VERSION(geom_mirror, 0);