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         sx_assert(&sc->sc_lock, SX_XLOCKED);
 211         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, ep);
 212         sx_xunlock(&sc->sc_lock);
 213         while ((ep->e_flags & G_MIRROR_EVENT_DONE) == 0) {
 214                 mtx_lock(&sc->sc_events_mtx);
 215                 MSLEEP(ep, &sc->sc_events_mtx, PRIBIO | PDROP, "m:event",
 216                     hz * 5);
 217         }
 218         error = ep->e_error;
 219         g_mirror_event_free(ep);
 220         sx_xlock(&sc->sc_lock);
 221         return (error);
 222 }
 223
 224 static struct g_mirror_event *
 225 g_mirror_event_first(struct g_mirror_softc *sc)
 226 {
 227         struct g_mirror_event *ep;
 228
 229         mtx_lock(&sc->sc_events_mtx);
 230         ep = TAILQ_FIRST(&sc->sc_events);
 231         mtx_unlock(&sc->sc_events_mtx);
 232         return (ep);
 233 }
 234
 235 static void
 236 g_mirror_event_remove(struct g_mirror_softc *sc, struct g_mirror_event *ep)
 237 {
 238
 239         mtx_lock(&sc->sc_events_mtx);
 240         TAILQ_REMOVE(&sc->sc_events, ep, e_next);
 241         mtx_unlock(&sc->sc_events_mtx);
 242 }
 243
 244 static void
 245 g_mirror_event_cancel(struct g_mirror_disk *disk)
 246 {
 247         struct g_mirror_softc *sc;
 248         struct g_mirror_event *ep, *tmpep;
 249
 250         sc = disk->d_softc;
 251         sx_assert(&sc->sc_lock, SX_XLOCKED);
 252
 253         mtx_lock(&sc->sc_events_mtx);
 254         TAILQ_FOREACH_SAFE(ep, &sc->sc_events, e_next, tmpep) {
 255                 if ((ep->e_flags & G_MIRROR_EVENT_DEVICE) != 0)
 256                         continue;
 257                 if (ep->e_disk != disk)
 258                         continue;
 259                 TAILQ_REMOVE(&sc->sc_events, ep, e_next);
 260                 if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 261                         g_mirror_event_free(ep);
 262                 else {
 263                         ep->e_error = ECANCELED;
 264                         wakeup(ep);
 265                 }
 266         }
 267         mtx_unlock(&sc->sc_events_mtx);
 268 }
 269
 270 /*
 271  * Return the number of disks in given state.
 272  * If state is equal to -1, count all connected disks.
 273  */
 274 u_int
 275 g_mirror_ndisks(struct g_mirror_softc *sc, int state)
 276 {
 277         struct g_mirror_disk *disk;
 278         u_int n = 0;
 279
 280         sx_assert(&sc->sc_lock, SX_LOCKED);
 281
 282         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 283                 if (state == -1 || disk->d_state == state)
 284                         n++;
 285         }
 286         return (n);
 287 }
 288
 289 /*
 290  * Find a disk in mirror by its disk ID.
 291  */
 292 static struct g_mirror_disk *
 293 g_mirror_id2disk(struct g_mirror_softc *sc, uint32_t id)
 294 {
 295         struct g_mirror_disk *disk;
 296
 297         sx_assert(&sc->sc_lock, SX_XLOCKED);
 298
 299         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 300                 if (disk->d_id == id)
 301                         return (disk);
 302         }
 303         return (NULL);
 304 }
 305
 306 static u_int
 307 g_mirror_nrequests(struct g_mirror_softc *sc, struct g_consumer *cp)
 308 {
 309         struct bio *bp;
 310         u_int nreqs = 0;
 311
 312         mtx_lock(&sc->sc_queue_mtx);
 313         TAILQ_FOREACH(bp, &sc->sc_queue, bio_queue) {
 314                 if (bp->bio_from == cp)
 315                         nreqs++;
 316         }
 317         mtx_unlock(&sc->sc_queue_mtx);
 318         return (nreqs);
 319 }
 320
 321 static int
 322 g_mirror_is_busy(struct g_mirror_softc *sc, struct g_consumer *cp)
 323 {
 324
 325         if (cp->index > 0) {
 326                 G_MIRROR_DEBUG(2,
 327                     "I/O requests for %s exist, can't destroy it now.",
 328                     cp->provider->name);
 329                 return (1);
 330         }
 331         if (g_mirror_nrequests(sc, cp) > 0) {
 332                 G_MIRROR_DEBUG(2,
 333                     "I/O requests for %s in queue, can't destroy it now.",
 334                     cp->provider->name);
 335                 return (1);
 336         }
 337         return (0);
 338 }
 339
 340 static void
 341 g_mirror_destroy_consumer(void *arg, int flags __unused)
 342 {
 343         struct g_consumer *cp;
 344
 345         g_topology_assert();
 346
 347         cp = arg;
 348         G_MIRROR_DEBUG(1, "Consumer %s destroyed.", cp->provider->name);
 349         g_detach(cp);
 350         g_destroy_consumer(cp);
 351 }
 352
 353 static void
 354 g_mirror_kill_consumer(struct g_mirror_softc *sc, struct g_consumer *cp)
 355 {
 356         struct g_provider *pp;
 357         int retaste_wait;
 358
 359         g_topology_assert();
 360
 361         cp->private = NULL;
 362         if (g_mirror_is_busy(sc, cp))
 363                 return;
 364         pp = cp->provider;
 365         retaste_wait = 0;
 366         if (cp->acw == 1) {
 367                 if ((pp->geom->flags & G_GEOM_WITHER) == 0)
 368                         retaste_wait = 1;
 369         }
 370         G_MIRROR_DEBUG(2, "Access %s r%dw%de%d = %d", pp->name, -cp->acr,
 371             -cp->acw, -cp->ace, 0);
 372         if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
 373                 g_access(cp, -cp->acr, -cp->acw, -cp->ace);
 374         if (retaste_wait) {
 375                 /*
 376                  * After retaste event was send (inside g_access()), we can send
 377                  * event to detach and destroy consumer.
 378                  * A class, which has consumer to the given provider connected
 379                  * will not receive retaste event for the provider.
 380                  * This is the way how I ignore retaste events when I close
 381                  * consumers opened for write: I detach and destroy consumer
 382                  * after retaste event is sent.
 383                  */
 384                 g_post_event(g_mirror_destroy_consumer, cp, M_WAITOK, NULL);
 385                 return;
 386         }
 387         G_MIRROR_DEBUG(1, "Consumer %s destroyed.", pp->name);
 388         g_detach(cp);
 389         g_destroy_consumer(cp);
 390 }
 391
 392 static int
 393 g_mirror_connect_disk(struct g_mirror_disk *disk, struct g_provider *pp)
 394 {
 395         struct g_consumer *cp;
 396         int error;
 397
 398         g_topology_assert_not();
 399         KASSERT(disk->d_consumer == NULL,
 400             ("Disk already connected (device %s).", disk->d_softc->sc_name));
 401
 402         g_topology_lock();
 403         cp = g_new_consumer(disk->d_softc->sc_geom);
 404         cp->flags |= G_CF_DIRECT_RECEIVE;
 405         error = g_attach(cp, pp);
 406         if (error != 0) {
 407                 g_destroy_consumer(cp);
 408                 g_topology_unlock();
 409                 return (error);
 410         }
 411         error = g_access(cp, 1, 1, 1);
 412         if (error != 0) {
 413                 g_detach(cp);
 414                 g_destroy_consumer(cp);
 415                 g_topology_unlock();
 416                 G_MIRROR_DEBUG(0, "Cannot open consumer %s (error=%d).",
 417                     pp->name, error);
 418                 return (error);
 419         }
 420         g_topology_unlock();
 421         disk->d_consumer = cp;
 422         disk->d_consumer->private = disk;
 423         disk->d_consumer->index = 0;
 424
 425         G_MIRROR_DEBUG(2, "Disk %s connected.", g_mirror_get_diskname(disk));
 426         return (0);
 427 }
 428
 429 static void
 430 g_mirror_disconnect_consumer(struct g_mirror_softc *sc, struct g_consumer *cp)
 431 {
 432
 433         g_topology_assert();
 434
 435         if (cp == NULL)
 436                 return;
 437         if (cp->provider != NULL)
 438                 g_mirror_kill_consumer(sc, cp);
 439         else
 440                 g_destroy_consumer(cp);
 441 }
 442
 443 /*
 444  * Initialize disk. This means allocate memory, create consumer, attach it
 445  * to the provider and open access (r1w1e1) to it.
 446  */
 447 static struct g_mirror_disk *
 448 g_mirror_init_disk(struct g_mirror_softc *sc, struct g_provider *pp,
 449     struct g_mirror_metadata *md, int *errorp)
 450 {
 451         struct g_mirror_disk *disk;
 452         int i, error;
 453
 454         disk = malloc(sizeof(*disk), M_MIRROR, M_NOWAIT | M_ZERO);
 455         if (disk == NULL) {
 456                 error = ENOMEM;
 457                 goto fail;
 458         }
 459         disk->d_softc = sc;
 460         error = g_mirror_connect_disk(disk, pp);
 461         if (error != 0)
 462                 goto fail;
 463         disk->d_id = md->md_did;
 464         disk->d_state = G_MIRROR_DISK_STATE_NONE;
 465         disk->d_priority = md->md_priority;
 466         disk->d_flags = md->md_dflags;
 467         error = g_getattr("GEOM::candelete", disk->d_consumer, &i);
 468         if (error == 0 && i != 0)
 469                 disk->d_flags |= G_MIRROR_DISK_FLAG_CANDELETE;
 470         if (md->md_provider[0] != '\0')
 471                 disk->d_flags |= G_MIRROR_DISK_FLAG_HARDCODED;
 472         disk->d_sync.ds_consumer = NULL;
 473         disk->d_sync.ds_offset = md->md_sync_offset;
 474         disk->d_sync.ds_offset_done = md->md_sync_offset;
 475         disk->d_sync.ds_update_ts = time_uptime;
 476         disk->d_genid = md->md_genid;
 477         disk->d_sync.ds_syncid = md->md_syncid;
 478         if (errorp != NULL)
 479                 *errorp = 0;
 480         return (disk);
 481 fail:
 482         if (errorp != NULL)
 483                 *errorp = error;
 484         if (disk != NULL)
 485                 free(disk, M_MIRROR);
 486         return (NULL);
 487 }
 488
 489 static void
 490 g_mirror_destroy_disk(struct g_mirror_disk *disk)
 491 {
 492         struct g_mirror_softc *sc;
 493
 494         g_topology_assert_not();
 495         sc = disk->d_softc;
 496         sx_assert(&sc->sc_lock, SX_XLOCKED);
 497
 498         LIST_REMOVE(disk, d_next);
 499         g_mirror_event_cancel(disk);
 500         if (sc->sc_hint == disk)
 501                 sc->sc_hint = NULL;
 502         switch (disk->d_state) {
 503         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
 504                 g_mirror_sync_stop(disk, 1);
 505                 /* FALLTHROUGH */
 506         case G_MIRROR_DISK_STATE_NEW:
 507         case G_MIRROR_DISK_STATE_STALE:
 508         case G_MIRROR_DISK_STATE_ACTIVE:
 509                 g_topology_lock();
 510                 g_mirror_disconnect_consumer(sc, disk->d_consumer);
 511                 g_topology_unlock();
 512                 free(disk, M_MIRROR);
 513                 break;
 514         default:
 515                 KASSERT(0 == 1, ("Wrong disk state (%s, %s).",
 516                     g_mirror_get_diskname(disk),
 517                     g_mirror_disk_state2str(disk->d_state)));
 518         }
 519 }
 520
 521 static void
 522 g_mirror_free_device(struct g_mirror_softc *sc)
 523 {
 524
 525         mtx_destroy(&sc->sc_queue_mtx);
 526         mtx_destroy(&sc->sc_events_mtx);
 527         mtx_destroy(&sc->sc_done_mtx);
 528         sx_destroy(&sc->sc_lock);
 529         free(sc, M_MIRROR);
 530 }
 531
 532 static void
 533 g_mirror_providergone(struct g_provider *pp)
 534 {
 535         struct g_mirror_softc *sc = pp->private;
 536
 537         if ((--sc->sc_refcnt) == 0)
 538                 g_mirror_free_device(sc);
 539 }
 540
 541 static void
 542 g_mirror_destroy_device(struct g_mirror_softc *sc)
 543 {
 544         struct g_mirror_disk *disk;
 545         struct g_mirror_event *ep;
 546         struct g_geom *gp;
 547         struct g_consumer *cp, *tmpcp;
 548
 549         g_topology_assert_not();
 550         sx_assert(&sc->sc_lock, SX_XLOCKED);
 551
 552         gp = sc->sc_geom;
 553         if (sc->sc_provider != NULL)
 554                 g_mirror_destroy_provider(sc);
 555         for (disk = LIST_FIRST(&sc->sc_disks); disk != NULL;
 556             disk = LIST_FIRST(&sc->sc_disks)) {
 557                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
 558                 g_mirror_update_metadata(disk);
 559                 g_mirror_destroy_disk(disk);
 560         }
 561         while ((ep = g_mirror_event_first(sc)) != NULL) {
 562                 g_mirror_event_remove(sc, ep);
 563                 if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 564                         g_mirror_event_free(ep);
 565                 else {
 566                         ep->e_error = ECANCELED;
 567                         ep->e_flags |= G_MIRROR_EVENT_DONE;
 568                         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, ep);
 569                         mtx_lock(&sc->sc_events_mtx);
 570                         wakeup(ep);
 571                         mtx_unlock(&sc->sc_events_mtx);
 572                 }
 573         }
 574         callout_drain(&sc->sc_callout);
 575
 576         g_topology_lock();
 577         LIST_FOREACH_SAFE(cp, &sc->sc_sync.ds_geom->consumer, consumer, tmpcp) {
 578                 g_mirror_disconnect_consumer(sc, cp);
 579         }
 580         g_wither_geom(sc->sc_sync.ds_geom, ENXIO);
 581         G_MIRROR_DEBUG(0, "Device %s destroyed.", gp->name);
 582         g_wither_geom(gp, ENXIO);
 583         sx_xunlock(&sc->sc_lock);
 584         if ((--sc->sc_refcnt) == 0)
 585                 g_mirror_free_device(sc);
 586         g_topology_unlock();
 587 }
 588
 589 static void
 590 g_mirror_orphan(struct g_consumer *cp)
 591 {
 592         struct g_mirror_disk *disk;
 593
 594         g_topology_assert();
 595
 596         disk = cp->private;
 597         if (disk == NULL)
 598                 return;
 599         disk->d_softc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
 600         g_mirror_event_send(disk, G_MIRROR_DISK_STATE_DISCONNECTED,
 601             G_MIRROR_EVENT_DONTWAIT);
 602 }
 603
 604 /*
 605  * Function should return the next active disk on the list.
 606  * It is possible that it will be the same disk as given.
 607  * If there are no active disks on list, NULL is returned.
 608  */
 609 static __inline struct g_mirror_disk *
 610 g_mirror_find_next(struct g_mirror_softc *sc, struct g_mirror_disk *disk)
 611 {
 612         struct g_mirror_disk *dp;
 613
 614         for (dp = LIST_NEXT(disk, d_next); dp != disk;
 615             dp = LIST_NEXT(dp, d_next)) {
 616                 if (dp == NULL)
 617                         dp = LIST_FIRST(&sc->sc_disks);
 618                 if (dp->d_state == G_MIRROR_DISK_STATE_ACTIVE)
 619                         break;
 620         }
 621         if (dp->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 622                 return (NULL);
 623         return (dp);
 624 }
 625
 626 static struct g_mirror_disk *
 627 g_mirror_get_disk(struct g_mirror_softc *sc)
 628 {
 629         struct g_mirror_disk *disk;
 630
 631         if (sc->sc_hint == NULL) {
 632                 sc->sc_hint = LIST_FIRST(&sc->sc_disks);
 633                 if (sc->sc_hint == NULL)
 634                         return (NULL);
 635         }
 636         disk = sc->sc_hint;
 637         if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE) {
 638                 disk = g_mirror_find_next(sc, disk);
 639                 if (disk == NULL)
 640                         return (NULL);
 641         }
 642         sc->sc_hint = g_mirror_find_next(sc, disk);
 643         return (disk);
 644 }
 645
 646 static int
 647 g_mirror_write_metadata(struct g_mirror_disk *disk,
 648     struct g_mirror_metadata *md)
 649 {
 650         struct g_mirror_softc *sc;
 651         struct g_consumer *cp;
 652         off_t offset, length;
 653         u_char *sector;
 654         int error = 0;
 655
 656         g_topology_assert_not();
 657         sc = disk->d_softc;
 658         sx_assert(&sc->sc_lock, SX_LOCKED);
 659
 660         cp = disk->d_consumer;
 661         KASSERT(cp != NULL, ("NULL consumer (%s).", sc->sc_name));
 662         KASSERT(cp->provider != NULL, ("NULL provider (%s).", sc->sc_name));
 663         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
 664             ("Consumer %s closed? (r%dw%de%d).", cp->provider->name, cp->acr,
 665             cp->acw, cp->ace));
 666         length = cp->provider->sectorsize;
 667         offset = cp->provider->mediasize - length;
 668         sector = malloc((size_t)length, M_MIRROR, M_WAITOK | M_ZERO);
 669         if (md != NULL &&
 670             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_WIPE) == 0) {
 671                 /*
 672                  * Handle the case, when the size of parent provider reduced.
 673                  */
 674                 if (offset < md->md_mediasize)
 675                         error = ENOSPC;
 676                 else
 677                         mirror_metadata_encode(md, sector);
 678         }
 679         KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_metadata_write, error);
 680         if (error == 0)
 681                 error = g_write_data(cp, offset, sector, length);
 682         free(sector, M_MIRROR);
 683         if (error != 0) {
 684                 if ((disk->d_flags & G_MIRROR_DISK_FLAG_BROKEN) == 0) {
 685                         disk->d_flags |= G_MIRROR_DISK_FLAG_BROKEN;
 686                         G_MIRROR_DEBUG(0, "Cannot write metadata on %s "
 687                             "(device=%s, error=%d).",
 688                             g_mirror_get_diskname(disk), sc->sc_name, error);
 689                 } else {
 690                         G_MIRROR_DEBUG(1, "Cannot write metadata on %s "
 691                             "(device=%s, error=%d).",
 692                             g_mirror_get_diskname(disk), sc->sc_name, error);
 693                 }
 694                 if (g_mirror_disconnect_on_failure &&
 695                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 1) {
 696                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
 697                         g_mirror_event_send(disk,
 698                             G_MIRROR_DISK_STATE_DISCONNECTED,
 699                             G_MIRROR_EVENT_DONTWAIT);
 700                 }
 701         }
 702         return (error);
 703 }
 704
 705 static int
 706 g_mirror_clear_metadata(struct g_mirror_disk *disk)
 707 {
 708         int error;
 709
 710         g_topology_assert_not();
 711         sx_assert(&disk->d_softc->sc_lock, SX_LOCKED);
 712
 713         if (disk->d_softc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
 714                 return (0);
 715         error = g_mirror_write_metadata(disk, NULL);
 716         if (error == 0) {
 717                 G_MIRROR_DEBUG(2, "Metadata on %s cleared.",
 718                     g_mirror_get_diskname(disk));
 719         } else {
 720                 G_MIRROR_DEBUG(0,
 721                     "Cannot clear metadata on disk %s (error=%d).",
 722                     g_mirror_get_diskname(disk), error);
 723         }
 724         return (error);
 725 }
 726
 727 void
 728 g_mirror_fill_metadata(struct g_mirror_softc *sc, struct g_mirror_disk *disk,
 729     struct g_mirror_metadata *md)
 730 {
 731
 732         strlcpy(md->md_magic, G_MIRROR_MAGIC, sizeof(md->md_magic));
 733         md->md_version = G_MIRROR_VERSION;
 734         strlcpy(md->md_name, sc->sc_name, sizeof(md->md_name));
 735         md->md_mid = sc->sc_id;
 736         md->md_all = sc->sc_ndisks;
 737         md->md_slice = sc->sc_slice;
 738         md->md_balance = sc->sc_balance;
 739         md->md_genid = sc->sc_genid;
 740         md->md_mediasize = sc->sc_mediasize;
 741         md->md_sectorsize = sc->sc_sectorsize;
 742         md->md_mflags = (sc->sc_flags & G_MIRROR_DEVICE_FLAG_MASK);
 743         bzero(md->md_provider, sizeof(md->md_provider));
 744         if (disk == NULL) {
 745                 md->md_did = arc4random();
 746                 md->md_priority = 0;
 747                 md->md_syncid = 0;
 748                 md->md_dflags = 0;
 749                 md->md_sync_offset = 0;
 750                 md->md_provsize = 0;
 751         } else {
 752                 md->md_did = disk->d_id;
 753                 md->md_priority = disk->d_priority;
 754                 md->md_syncid = disk->d_sync.ds_syncid;
 755                 md->md_dflags = (disk->d_flags & G_MIRROR_DISK_FLAG_MASK);
 756                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
 757                         md->md_sync_offset = disk->d_sync.ds_offset_done;
 758                 else
 759                         md->md_sync_offset = 0;
 760                 if ((disk->d_flags & G_MIRROR_DISK_FLAG_HARDCODED) != 0) {
 761                         strlcpy(md->md_provider,
 762                             disk->d_consumer->provider->name,
 763                             sizeof(md->md_provider));
 764                 }
 765                 md->md_provsize = disk->d_consumer->provider->mediasize;
 766         }
 767 }
 768
 769 void
 770 g_mirror_update_metadata(struct g_mirror_disk *disk)
 771 {
 772         struct g_mirror_softc *sc;
 773         struct g_mirror_metadata md;
 774         int error;
 775
 776         g_topology_assert_not();
 777         sc = disk->d_softc;
 778         sx_assert(&sc->sc_lock, SX_LOCKED);
 779
 780         if (sc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
 781                 return;
 782         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_WIPE) == 0)
 783                 g_mirror_fill_metadata(sc, disk, &md);
 784         error = g_mirror_write_metadata(disk, &md);
 785         if (error == 0) {
 786                 G_MIRROR_DEBUG(2, "Metadata on %s updated.",
 787                     g_mirror_get_diskname(disk));
 788         } else {
 789                 G_MIRROR_DEBUG(0,
 790                     "Cannot update metadata on disk %s (error=%d).",
 791                     g_mirror_get_diskname(disk), error);
 792         }
 793 }
 794
 795 static void
 796 g_mirror_bump_syncid(struct g_mirror_softc *sc)
 797 {
 798         struct g_mirror_disk *disk;
 799
 800         g_topology_assert_not();
 801         sx_assert(&sc->sc_lock, SX_XLOCKED);
 802         KASSERT(g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 0,
 803             ("%s called with no active disks (device=%s).", __func__,
 804             sc->sc_name));
 805
 806         sc->sc_syncid++;
 807         G_MIRROR_DEBUG(1, "Device %s: syncid bumped to %u.", sc->sc_name,
 808             sc->sc_syncid);
 809         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 810                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
 811                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
 812                         disk->d_sync.ds_syncid = sc->sc_syncid;
 813                         g_mirror_update_metadata(disk);
 814                 }
 815         }
 816 }
 817
 818 static void
 819 g_mirror_bump_genid(struct g_mirror_softc *sc)
 820 {
 821         struct g_mirror_disk *disk;
 822
 823         g_topology_assert_not();
 824         sx_assert(&sc->sc_lock, SX_XLOCKED);
 825         KASSERT(g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 0,
 826             ("%s called with no active disks (device=%s).", __func__,
 827             sc->sc_name));
 828
 829         sc->sc_genid++;
 830         G_MIRROR_DEBUG(1, "Device %s: genid bumped to %u.", sc->sc_name,
 831             sc->sc_genid);
 832         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 833                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
 834                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
 835                         disk->d_genid = sc->sc_genid;
 836                         g_mirror_update_metadata(disk);
 837                 }
 838         }
 839 }
 840
 841 static int
 842 g_mirror_idle(struct g_mirror_softc *sc, int acw)
 843 {
 844         struct g_mirror_disk *disk;
 845         int timeout;
 846
 847         g_topology_assert_not();
 848         sx_assert(&sc->sc_lock, SX_XLOCKED);
 849
 850         if (sc->sc_provider == NULL)
 851                 return (0);
 852         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
 853                 return (0);
 854         if (sc->sc_idle)
 855                 return (0);
 856         if (sc->sc_writes > 0)
 857                 return (0);
 858         if (acw > 0 || (acw == -1 && sc->sc_provider->acw > 0)) {
 859                 timeout = g_mirror_idletime - (time_uptime - sc->sc_last_write);
 860                 if (!g_mirror_shutdown && timeout > 0)
 861                         return (timeout);
 862         }
 863         sc->sc_idle = 1;
 864         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 865                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 866                         continue;
 867                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as clean.",
 868                     g_mirror_get_diskname(disk), sc->sc_name);
 869                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
 870                 g_mirror_update_metadata(disk);
 871         }
 872         return (0);
 873 }
 874
 875 static void
 876 g_mirror_unidle(struct g_mirror_softc *sc)
 877 {
 878         struct g_mirror_disk *disk;
 879
 880         g_topology_assert_not();
 881         sx_assert(&sc->sc_lock, SX_XLOCKED);
 882
 883         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
 884                 return;
 885         sc->sc_idle = 0;
 886         sc->sc_last_write = time_uptime;
 887         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 888                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 889                         continue;
 890                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as dirty.",
 891                     g_mirror_get_diskname(disk), sc->sc_name);
 892                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
 893                 g_mirror_update_metadata(disk);
 894         }
 895 }
 896
 897 static void
 898 g_mirror_done(struct bio *bp)
 899 {
 900         struct g_mirror_softc *sc;
 901
 902         sc = bp->bio_from->geom->softc;
 903         bp->bio_cflags = G_MIRROR_BIO_FLAG_REGULAR;
 904         mtx_lock(&sc->sc_queue_mtx);
 905         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
 906         mtx_unlock(&sc->sc_queue_mtx);
 907         wakeup(sc);
 908 }
 909
 910 static void
 911 g_mirror_regular_request_error(struct g_mirror_softc *sc,
 912     struct g_mirror_disk *disk, struct bio *bp)
 913 {
 914
 915         if (bp->bio_cmd == BIO_FLUSH && bp->bio_error == EOPNOTSUPP)
 916                 return;
 917
 918         if ((disk->d_flags & G_MIRROR_DISK_FLAG_BROKEN) == 0) {
 919                 disk->d_flags |= G_MIRROR_DISK_FLAG_BROKEN;
 920                 G_MIRROR_LOGREQ(0, bp, "Request failed (error=%d).",
 921                     bp->bio_error);
 922         } else {
 923                 G_MIRROR_LOGREQ(1, bp, "Request failed (error=%d).",
 924                     bp->bio_error);
 925         }
 926         if (g_mirror_disconnect_on_failure &&
 927             g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 1) {
 928                 if (bp->bio_error == ENXIO &&
 929                     bp->bio_cmd == BIO_READ)
 930                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
 931                 else if (bp->bio_error == ENXIO)
 932                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID_NOW;
 933                 else
 934                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
 935                 g_mirror_event_send(disk, G_MIRROR_DISK_STATE_DISCONNECTED,
 936                     G_MIRROR_EVENT_DONTWAIT);
 937         }
 938 }
 939
 940 static void
 941 g_mirror_regular_request(struct g_mirror_softc *sc, struct bio *bp)
 942 {
 943         struct g_mirror_disk *disk;
 944         struct bio *pbp;
 945
 946         g_topology_assert_not();
 947         KASSERT(sc->sc_provider == bp->bio_parent->bio_to,
 948             ("regular request %p with unexpected origin", bp));
 949
 950         pbp = bp->bio_parent;
 951         bp->bio_from->index--;
 952         if (bp->bio_cmd == BIO_WRITE || bp->bio_cmd == BIO_DELETE)
 953                 sc->sc_writes--;
 954         disk = bp->bio_from->private;
 955         if (disk == NULL) {
 956                 g_topology_lock();
 957                 g_mirror_kill_consumer(sc, bp->bio_from);
 958                 g_topology_unlock();
 959         }
 960
 961         switch (bp->bio_cmd) {
 962         case BIO_READ:
 963                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_read,
 964                     bp->bio_error);
 965                 break;
 966         case BIO_WRITE:
 967                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_write,
 968                     bp->bio_error);
 969                 break;
 970         case BIO_DELETE:
 971                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_delete,
 972                     bp->bio_error);
 973                 break;
 974         case BIO_FLUSH:
 975                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_flush,
 976                     bp->bio_error);
 977                 break;
 978         }
 979
 980         pbp->bio_inbed++;
 981         KASSERT(pbp->bio_inbed <= pbp->bio_children,
 982             ("bio_inbed (%u) is bigger than bio_children (%u).", pbp->bio_inbed,
 983             pbp->bio_children));
 984         if (bp->bio_error == 0 && pbp->bio_error == 0) {
 985                 G_MIRROR_LOGREQ(3, bp, "Request delivered.");
 986                 g_destroy_bio(bp);
 987                 if (pbp->bio_children == pbp->bio_inbed) {
 988                         G_MIRROR_LOGREQ(3, pbp, "Request delivered.");
 989                         pbp->bio_completed = pbp->bio_length;
 990                         if (pbp->bio_cmd == BIO_WRITE ||
 991                             pbp->bio_cmd == BIO_DELETE) {
 992                                 TAILQ_REMOVE(&sc->sc_inflight, pbp, bio_queue);
 993                                 /* Release delayed sync requests if possible. */
 994                                 g_mirror_sync_release(sc);
 995                         }
 996                         g_io_deliver(pbp, pbp->bio_error);
 997                 }
 998                 return;
 999         } else if (bp->bio_error != 0) {
1000                 if (pbp->bio_error == 0)
1001                         pbp->bio_error = bp->bio_error;
1002                 if (disk != NULL)
1003                         g_mirror_regular_request_error(sc, disk, bp);
1004                 switch (pbp->bio_cmd) {
1005                 case BIO_DELETE:
1006                 case BIO_WRITE:
1007                 case BIO_FLUSH:
1008                         pbp->bio_inbed--;
1009                         pbp->bio_children--;
1010                         break;
1011                 }
1012         }
1013         g_destroy_bio(bp);
1014
1015         switch (pbp->bio_cmd) {
1016         case BIO_READ:
1017                 if (pbp->bio_inbed < pbp->bio_children)
1018                         break;
1019                 if (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 1)
1020                         g_io_deliver(pbp, pbp->bio_error);
1021                 else {
1022                         pbp->bio_error = 0;
1023                         mtx_lock(&sc->sc_queue_mtx);
1024                         TAILQ_INSERT_TAIL(&sc->sc_queue, pbp, bio_queue);
1025                         mtx_unlock(&sc->sc_queue_mtx);
1026                         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
1027                         wakeup(sc);
1028                 }
1029                 break;
1030         case BIO_DELETE:
1031         case BIO_WRITE:
1032         case BIO_FLUSH:
1033                 if (pbp->bio_children == 0) {
1034                         /*
1035                          * All requests failed.
1036                          */
1037                 } else if (pbp->bio_inbed < pbp->bio_children) {
1038                         /* Do nothing. */
1039                         break;
1040                 } else if (pbp->bio_children == pbp->bio_inbed) {
1041                         /* Some requests succeeded. */
1042                         pbp->bio_error = 0;
1043                         pbp->bio_completed = pbp->bio_length;
1044                 }
1045                 if (pbp->bio_cmd == BIO_WRITE || pbp->bio_cmd == BIO_DELETE) {
1046                         TAILQ_REMOVE(&sc->sc_inflight, pbp, bio_queue);
1047                         /* Release delayed sync requests if possible. */
1048                         g_mirror_sync_release(sc);
1049                 }
1050                 g_io_deliver(pbp, pbp->bio_error);
1051                 break;
1052         default:
1053                 KASSERT(1 == 0, ("Invalid request: %u.", pbp->bio_cmd));
1054                 break;
1055         }
1056 }
1057
1058 static void
1059 g_mirror_sync_done(struct bio *bp)
1060 {
1061         struct g_mirror_softc *sc;
1062
1063         G_MIRROR_LOGREQ(3, bp, "Synchronization request delivered.");
1064         sc = bp->bio_from->geom->softc;
1065         bp->bio_cflags = G_MIRROR_BIO_FLAG_SYNC;
1066         mtx_lock(&sc->sc_queue_mtx);
1067         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
1068         mtx_unlock(&sc->sc_queue_mtx);
1069         wakeup(sc);
1070 }
1071
1072 static void
1073 g_mirror_candelete(struct bio *bp)
1074 {
1075         struct g_mirror_softc *sc;
1076         struct g_mirror_disk *disk;
1077         int *val;
1078
1079         sc = bp->bio_to->private;
1080         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1081                 if (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE)
1082                         break;
1083         }
1084         val = (int *)bp->bio_data;
1085         *val = (disk != NULL);
1086         g_io_deliver(bp, 0);
1087 }
1088
1089 static void
1090 g_mirror_kernel_dump(struct bio *bp)
1091 {
1092         struct g_mirror_softc *sc;
1093         struct g_mirror_disk *disk;
1094         struct bio *cbp;
1095         struct g_kerneldump *gkd;
1096
1097         /*
1098          * We configure dumping to the first component, because this component
1099          * will be used for reading with 'prefer' balance algorithm.
1100          * If the component with the highest priority is currently disconnected
1101          * we will not be able to read the dump after the reboot if it will be
1102          * connected and synchronized later. Can we do something better?
1103          */
1104         sc = bp->bio_to->private;
1105         disk = LIST_FIRST(&sc->sc_disks);
1106
1107         gkd = (struct g_kerneldump *)bp->bio_data;
1108         if (gkd->length > bp->bio_to->mediasize)
1109                 gkd->length = bp->bio_to->mediasize;
1110         cbp = g_clone_bio(bp);
1111         if (cbp == NULL) {
1112                 g_io_deliver(bp, ENOMEM);
1113                 return;
1114         }
1115         cbp->bio_done = g_std_done;
1116         g_io_request(cbp, disk->d_consumer);
1117         G_MIRROR_DEBUG(1, "Kernel dump will go to %s.",
1118             g_mirror_get_diskname(disk));
1119 }
1120
1121 static void
1122 g_mirror_start(struct bio *bp)
1123 {
1124         struct g_mirror_softc *sc;
1125
1126         sc = bp->bio_to->private;
1127         /*
1128          * If sc == NULL or there are no valid disks, provider's error
1129          * should be set and g_mirror_start() should not be called at all.
1130          */
1131         KASSERT(sc != NULL && sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
1132             ("Provider's error should be set (error=%d)(mirror=%s).",
1133             bp->bio_to->error, bp->bio_to->name));
1134         G_MIRROR_LOGREQ(3, bp, "Request received.");
1135
1136         switch (bp->bio_cmd) {
1137         case BIO_READ:
1138         case BIO_WRITE:
1139         case BIO_DELETE:
1140         case BIO_FLUSH:
1141                 break;
1142         case BIO_GETATTR:
1143                 if (!strcmp(bp->bio_attribute, "GEOM::candelete")) {
1144                         g_mirror_candelete(bp);
1145                         return;
1146                 } else if (strcmp("GEOM::kerneldump", bp->bio_attribute) == 0) {
1147                         g_mirror_kernel_dump(bp);
1148                         return;
1149                 }
1150                 /* FALLTHROUGH */
1151         default:
1152                 g_io_deliver(bp, EOPNOTSUPP);
1153                 return;
1154         }
1155         mtx_lock(&sc->sc_queue_mtx);
1156         if (bp->bio_to->error != 0) {
1157                 mtx_unlock(&sc->sc_queue_mtx);
1158                 g_io_deliver(bp, bp->bio_to->error);
1159                 return;
1160         }
1161         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
1162         mtx_unlock(&sc->sc_queue_mtx);
1163         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
1164         wakeup(sc);
1165 }
1166
1167 /*
1168  * Return TRUE if the given request is colliding with a in-progress
1169  * synchronization request.
1170  */
1171 static bool
1172 g_mirror_sync_collision(struct g_mirror_softc *sc, struct bio *bp)
1173 {
1174         struct g_mirror_disk *disk;
1175         struct bio *sbp;
1176         off_t rstart, rend, sstart, send;
1177         u_int i;
1178
1179         if (sc->sc_sync.ds_ndisks == 0)
1180                 return (false);
1181         rstart = bp->bio_offset;
1182         rend = bp->bio_offset + bp->bio_length;
1183         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1184                 if (disk->d_state != G_MIRROR_DISK_STATE_SYNCHRONIZING)
1185                         continue;
1186                 for (i = 0; i < g_mirror_syncreqs; i++) {
1187                         sbp = disk->d_sync.ds_bios[i];
1188                         if (sbp == NULL)
1189                                 continue;
1190                         sstart = sbp->bio_offset;
1191                         send = sbp->bio_offset + sbp->bio_length;
1192                         if (rend > sstart && rstart < send)
1193                                 return (true);
1194                 }
1195         }
1196         return (false);
1197 }
1198
1199 /*
1200  * Return TRUE if the given sync request is colliding with a in-progress regular
1201  * request.
1202  */
1203 static bool
1204 g_mirror_regular_collision(struct g_mirror_softc *sc, struct bio *sbp)
1205 {
1206         off_t rstart, rend, sstart, send;
1207         struct bio *bp;
1208
1209         if (sc->sc_sync.ds_ndisks == 0)
1210                 return (false);
1211         sstart = sbp->bio_offset;
1212         send = sbp->bio_offset + sbp->bio_length;
1213         TAILQ_FOREACH(bp, &sc->sc_inflight, bio_queue) {
1214                 rstart = bp->bio_offset;
1215                 rend = bp->bio_offset + bp->bio_length;
1216                 if (rend > sstart && rstart < send)
1217                         return (true);
1218         }
1219         return (false);
1220 }
1221
1222 /*
1223  * Puts regular request onto delayed queue.
1224  */
1225 static void
1226 g_mirror_regular_delay(struct g_mirror_softc *sc, struct bio *bp)
1227 {
1228
1229         G_MIRROR_LOGREQ(2, bp, "Delaying request.");
1230         TAILQ_INSERT_TAIL(&sc->sc_regular_delayed, bp, bio_queue);
1231 }
1232
1233 /*
1234  * Puts synchronization request onto delayed queue.
1235  */
1236 static void
1237 g_mirror_sync_delay(struct g_mirror_softc *sc, struct bio *bp)
1238 {
1239
1240         G_MIRROR_LOGREQ(2, bp, "Delaying synchronization request.");
1241         TAILQ_INSERT_TAIL(&sc->sc_sync_delayed, bp, bio_queue);
1242 }
1243
1244 /*
1245  * Requeue delayed regular requests.
1246  */
1247 static void
1248 g_mirror_regular_release(struct g_mirror_softc *sc)
1249 {
1250         struct bio *bp;
1251
1252         if ((bp = TAILQ_FIRST(&sc->sc_regular_delayed)) == NULL)
1253                 return;
1254         if (g_mirror_sync_collision(sc, bp))
1255                 return;
1256
1257         G_MIRROR_DEBUG(2, "Requeuing regular requests after collision.");
1258         mtx_lock(&sc->sc_queue_mtx);
1259         TAILQ_CONCAT(&sc->sc_regular_delayed, &sc->sc_queue, bio_queue);
1260         TAILQ_SWAP(&sc->sc_regular_delayed, &sc->sc_queue, bio, bio_queue);
1261         mtx_unlock(&sc->sc_queue_mtx);
1262 }
1263
1264 /*
1265  * Releases delayed sync requests which don't collide anymore with regular
1266  * requests.
1267  */
1268 static void
1269 g_mirror_sync_release(struct g_mirror_softc *sc)
1270 {
1271         struct bio *bp, *bp2;
1272
1273         TAILQ_FOREACH_SAFE(bp, &sc->sc_sync_delayed, bio_queue, bp2) {
1274                 if (g_mirror_regular_collision(sc, bp))
1275                         continue;
1276                 TAILQ_REMOVE(&sc->sc_sync_delayed, bp, bio_queue);
1277                 G_MIRROR_LOGREQ(2, bp,
1278                     "Releasing delayed synchronization request.");
1279                 g_io_request(bp, bp->bio_from);
1280         }
1281 }
1282
1283 /*
1284  * Free a synchronization request and clear its slot in the array.
1285  */
1286 static void
1287 g_mirror_sync_request_free(struct g_mirror_disk *disk, struct bio *bp)
1288 {
1289         int idx;
1290
1291         if (disk != NULL && disk->d_sync.ds_bios != NULL) {
1292                 idx = (int)(uintptr_t)bp->bio_caller1;
1293                 KASSERT(disk->d_sync.ds_bios[idx] == bp,
1294                     ("unexpected sync BIO at %p:%d", disk, idx));
1295                 disk->d_sync.ds_bios[idx] = NULL;
1296         }
1297         free(bp->bio_data, M_MIRROR);
1298         g_destroy_bio(bp);
1299 }
1300
1301 /*
1302  * Handle synchronization requests.
1303  * Every synchronization request is a two-step process: first, a read request is
1304  * sent to the mirror provider via the sync consumer. If that request completes
1305  * successfully, it is converted to a write and sent to the disk being
1306  * synchronized. If the write also completes successfully, the synchronization
1307  * offset is advanced and a new read request is submitted.
1308  */
1309 static void
1310 g_mirror_sync_request(struct g_mirror_softc *sc, struct bio *bp)
1311 {
1312         struct g_mirror_disk *disk;
1313         struct g_mirror_disk_sync *sync;
1314
1315         KASSERT((bp->bio_cmd == BIO_READ &&
1316             bp->bio_from->geom == sc->sc_sync.ds_geom) ||
1317             (bp->bio_cmd == BIO_WRITE && bp->bio_from->geom == sc->sc_geom),
1318             ("Sync BIO %p with unexpected origin", bp));
1319
1320         bp->bio_from->index--;
1321         disk = bp->bio_from->private;
1322         if (disk == NULL) {
1323                 sx_xunlock(&sc->sc_lock); /* Avoid recursion on sc_lock. */
1324                 g_topology_lock();
1325                 g_mirror_kill_consumer(sc, bp->bio_from);
1326                 g_topology_unlock();
1327                 g_mirror_sync_request_free(NULL, bp);
1328                 sx_xlock(&sc->sc_lock);
1329                 return;
1330         }
1331
1332         sync = &disk->d_sync;
1333
1334         /*
1335          * Synchronization request.
1336          */
1337         switch (bp->bio_cmd) {
1338         case BIO_READ: {
1339                 struct g_consumer *cp;
1340
1341                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_sync_request_read,
1342                     bp->bio_error);
1343
1344                 if (bp->bio_error != 0) {
1345                         G_MIRROR_LOGREQ(0, bp,
1346                             "Synchronization request failed (error=%d).",
1347                             bp->bio_error);
1348
1349                         /*
1350                          * The read error will trigger a syncid bump, so there's
1351                          * no need to do that here.
1352                          *
1353                          * The read error handling for regular requests will
1354                          * retry the read from all active mirrors before passing
1355                          * the error back up, so there's no need to retry here.
1356                          */
1357                         g_mirror_sync_request_free(disk, bp);
1358                         g_mirror_event_send(disk,
1359                             G_MIRROR_DISK_STATE_DISCONNECTED,
1360                             G_MIRROR_EVENT_DONTWAIT);
1361                         return;
1362                 }
1363                 G_MIRROR_LOGREQ(3, bp,
1364                     "Synchronization request half-finished.");
1365                 bp->bio_cmd = BIO_WRITE;
1366                 bp->bio_cflags = 0;
1367                 cp = disk->d_consumer;
1368                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1369                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1370                     cp->acr, cp->acw, cp->ace));
1371                 cp->index++;
1372                 g_io_request(bp, cp);
1373                 return;
1374         }
1375         case BIO_WRITE: {
1376                 off_t offset;
1377                 int i;
1378
1379                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_sync_request_write,
1380                     bp->bio_error);
1381
1382                 if (bp->bio_error != 0) {
1383                         G_MIRROR_LOGREQ(0, bp,
1384                             "Synchronization request failed (error=%d).",
1385                             bp->bio_error);
1386                         g_mirror_sync_request_free(disk, bp);
1387                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
1388                         g_mirror_event_send(disk,
1389                             G_MIRROR_DISK_STATE_DISCONNECTED,
1390                             G_MIRROR_EVENT_DONTWAIT);
1391                         return;
1392                 }
1393                 G_MIRROR_LOGREQ(3, bp, "Synchronization request finished.");
1394                 if (sync->ds_offset >= sc->sc_mediasize ||
1395                     sync->ds_consumer == NULL ||
1396                     (sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1397                         /* Don't send more synchronization requests. */
1398                         sync->ds_inflight--;
1399                         g_mirror_sync_request_free(disk, bp);
1400                         if (sync->ds_inflight > 0)
1401                                 return;
1402                         if (sync->ds_consumer == NULL ||
1403                             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1404                                 return;
1405                         }
1406                         /* Disk up-to-date, activate it. */
1407                         g_mirror_event_send(disk, G_MIRROR_DISK_STATE_ACTIVE,
1408                             G_MIRROR_EVENT_DONTWAIT);
1409                         return;
1410                 }
1411
1412                 /* Send next synchronization request. */
1413                 g_mirror_sync_reinit(disk, bp, sync->ds_offset);
1414                 sync->ds_offset += bp->bio_length;
1415
1416                 G_MIRROR_LOGREQ(3, bp, "Sending synchronization request.");
1417                 sync->ds_consumer->index++;
1418
1419                 /*
1420                  * Delay the request if it is colliding with a regular request.
1421                  */
1422                 if (g_mirror_regular_collision(sc, bp))
1423                         g_mirror_sync_delay(sc, bp);
1424                 else
1425                         g_io_request(bp, sync->ds_consumer);
1426
1427                 /* Requeue delayed requests if possible. */
1428                 g_mirror_regular_release(sc);
1429
1430                 /* Find the smallest offset */
1431                 offset = sc->sc_mediasize;
1432                 for (i = 0; i < g_mirror_syncreqs; i++) {
1433                         bp = sync->ds_bios[i];
1434                         if (bp != NULL && bp->bio_offset < offset)
1435                                 offset = bp->bio_offset;
1436                 }
1437                 if (g_mirror_sync_period > 0 &&
1438                     time_uptime - sync->ds_update_ts > g_mirror_sync_period) {
1439                         sync->ds_offset_done = offset;
1440                         g_mirror_update_metadata(disk);
1441                         sync->ds_update_ts = time_uptime;
1442                 }
1443                 return;
1444         }
1445         default:
1446                 panic("Invalid I/O request %p", bp);
1447         }
1448 }
1449
1450 static void
1451 g_mirror_request_prefer(struct g_mirror_softc *sc, struct bio *bp)
1452 {
1453         struct g_mirror_disk *disk;
1454         struct g_consumer *cp;
1455         struct bio *cbp;
1456
1457         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1458                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE)
1459                         break;
1460         }
1461         if (disk == NULL) {
1462                 if (bp->bio_error == 0)
1463                         bp->bio_error = ENXIO;
1464                 g_io_deliver(bp, bp->bio_error);
1465                 return;
1466         }
1467         cbp = g_clone_bio(bp);
1468         if (cbp == NULL) {
1469                 if (bp->bio_error == 0)
1470                         bp->bio_error = ENOMEM;
1471                 g_io_deliver(bp, bp->bio_error);
1472                 return;
1473         }
1474         /*
1475          * Fill in the component buf structure.
1476          */
1477         cp = disk->d_consumer;
1478         cbp->bio_done = g_mirror_done;
1479         cbp->bio_to = cp->provider;
1480         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1481         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1482             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1483             cp->acw, cp->ace));
1484         cp->index++;
1485         g_io_request(cbp, cp);
1486 }
1487
1488 static void
1489 g_mirror_request_round_robin(struct g_mirror_softc *sc, struct bio *bp)
1490 {
1491         struct g_mirror_disk *disk;
1492         struct g_consumer *cp;
1493         struct bio *cbp;
1494
1495         disk = g_mirror_get_disk(sc);
1496         if (disk == NULL) {
1497                 if (bp->bio_error == 0)
1498                         bp->bio_error = ENXIO;
1499                 g_io_deliver(bp, bp->bio_error);
1500                 return;
1501         }
1502         cbp = g_clone_bio(bp);
1503         if (cbp == NULL) {
1504                 if (bp->bio_error == 0)
1505                         bp->bio_error = ENOMEM;
1506                 g_io_deliver(bp, bp->bio_error);
1507                 return;
1508         }
1509         /*
1510          * Fill in the component buf structure.
1511          */
1512         cp = disk->d_consumer;
1513         cbp->bio_done = g_mirror_done;
1514         cbp->bio_to = cp->provider;
1515         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1516         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1517             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1518             cp->acw, cp->ace));
1519         cp->index++;
1520         g_io_request(cbp, cp);
1521 }
1522
1523 #define TRACK_SIZE  (1 * 1024 * 1024)
1524 #define LOAD_SCALE      256
1525 #define ABS(x)          (((x) >= 0) ? (x) : (-(x)))
1526
1527 static void
1528 g_mirror_request_load(struct g_mirror_softc *sc, struct bio *bp)
1529 {
1530         struct g_mirror_disk *disk, *dp;
1531         struct g_consumer *cp;
1532         struct bio *cbp;
1533         int prio, best;
1534
1535         /* Find a disk with the smallest load. */
1536         disk = NULL;
1537         best = INT_MAX;
1538         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
1539                 if (dp->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1540                         continue;
1541                 prio = dp->load;
1542                 /* If disk head is precisely in position - highly prefer it. */
1543                 if (dp->d_last_offset == bp->bio_offset)
1544                         prio -= 2 * LOAD_SCALE;
1545                 else
1546                 /* If disk head is close to position - prefer it. */
1547                 if (ABS(dp->d_last_offset - bp->bio_offset) < TRACK_SIZE)
1548                         prio -= 1 * LOAD_SCALE;
1549                 if (prio <= best) {
1550                         disk = dp;
1551                         best = prio;
1552                 }
1553         }
1554         KASSERT(disk != NULL, ("NULL disk for %s.", sc->sc_name));
1555         cbp = g_clone_bio(bp);
1556         if (cbp == NULL) {
1557                 if (bp->bio_error == 0)
1558                         bp->bio_error = ENOMEM;
1559                 g_io_deliver(bp, bp->bio_error);
1560                 return;
1561         }
1562         /*
1563          * Fill in the component buf structure.
1564          */
1565         cp = disk->d_consumer;
1566         cbp->bio_done = g_mirror_done;
1567         cbp->bio_to = cp->provider;
1568         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1569         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1570             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1571             cp->acw, cp->ace));
1572         cp->index++;
1573         /* Remember last head position */
1574         disk->d_last_offset = bp->bio_offset + bp->bio_length;
1575         /* Update loads. */
1576         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
1577                 dp->load = (dp->d_consumer->index * LOAD_SCALE +
1578                     dp->load * 7) / 8;
1579         }
1580         g_io_request(cbp, cp);
1581 }
1582
1583 static void
1584 g_mirror_request_split(struct g_mirror_softc *sc, struct bio *bp)
1585 {
1586         struct bio_queue queue;
1587         struct g_mirror_disk *disk;
1588         struct g_consumer *cp;
1589         struct bio *cbp;
1590         off_t left, mod, offset, slice;
1591         u_char *data;
1592         u_int ndisks;
1593
1594         if (bp->bio_length <= sc->sc_slice) {
1595                 g_mirror_request_round_robin(sc, bp);
1596                 return;
1597         }
1598         ndisks = g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE);
1599         slice = bp->bio_length / ndisks;
1600         mod = slice % sc->sc_provider->sectorsize;
1601         if (mod != 0)
1602                 slice += sc->sc_provider->sectorsize - mod;
1603         /*
1604          * Allocate all bios before sending any request, so we can
1605          * return ENOMEM in nice and clean way.
1606          */
1607         left = bp->bio_length;
1608         offset = bp->bio_offset;
1609         data = bp->bio_data;
1610         TAILQ_INIT(&queue);
1611         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1612                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1613                         continue;
1614                 cbp = g_clone_bio(bp);
1615                 if (cbp == NULL) {
1616                         while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1617                                 TAILQ_REMOVE(&queue, cbp, bio_queue);
1618                                 g_destroy_bio(cbp);
1619                         }
1620                         if (bp->bio_error == 0)
1621                                 bp->bio_error = ENOMEM;
1622                         g_io_deliver(bp, bp->bio_error);
1623                         return;
1624                 }
1625                 TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1626                 cbp->bio_done = g_mirror_done;
1627                 cbp->bio_caller1 = disk;
1628                 cbp->bio_to = disk->d_consumer->provider;
1629                 cbp->bio_offset = offset;
1630                 cbp->bio_data = data;
1631                 cbp->bio_length = MIN(left, slice);
1632                 left -= cbp->bio_length;
1633                 if (left == 0)
1634                         break;
1635                 offset += cbp->bio_length;
1636                 data += cbp->bio_length;
1637         }
1638         while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1639                 TAILQ_REMOVE(&queue, cbp, bio_queue);
1640                 G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1641                 disk = cbp->bio_caller1;
1642                 cbp->bio_caller1 = NULL;
1643                 cp = disk->d_consumer;
1644                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1645                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1646                     cp->acr, cp->acw, cp->ace));
1647                 disk->d_consumer->index++;
1648                 g_io_request(cbp, disk->d_consumer);
1649         }
1650 }
1651
1652 static void
1653 g_mirror_register_request(struct g_mirror_softc *sc, struct bio *bp)
1654 {
1655         struct bio_queue queue;
1656         struct bio *cbp;
1657         struct g_consumer *cp;
1658         struct g_mirror_disk *disk;
1659
1660         sx_assert(&sc->sc_lock, SA_XLOCKED);
1661
1662         /*
1663          * To avoid ordering issues, if a write is deferred because of a
1664          * collision with a sync request, all I/O is deferred until that
1665          * write is initiated.
1666          */
1667         if (bp->bio_from->geom != sc->sc_sync.ds_geom &&
1668             !TAILQ_EMPTY(&sc->sc_regular_delayed)) {
1669                 g_mirror_regular_delay(sc, bp);
1670                 return;
1671         }
1672
1673         switch (bp->bio_cmd) {
1674         case BIO_READ:
1675                 switch (sc->sc_balance) {
1676                 case G_MIRROR_BALANCE_LOAD:
1677                         g_mirror_request_load(sc, bp);
1678                         break;
1679                 case G_MIRROR_BALANCE_PREFER:
1680                         g_mirror_request_prefer(sc, bp);
1681                         break;
1682                 case G_MIRROR_BALANCE_ROUND_ROBIN:
1683                         g_mirror_request_round_robin(sc, bp);
1684                         break;
1685                 case G_MIRROR_BALANCE_SPLIT:
1686                         g_mirror_request_split(sc, bp);
1687                         break;
1688                 }
1689                 return;
1690         case BIO_WRITE:
1691         case BIO_DELETE:
1692                 /*
1693                  * Delay the request if it is colliding with a synchronization
1694                  * request.
1695                  */
1696                 if (g_mirror_sync_collision(sc, bp)) {
1697                         g_mirror_regular_delay(sc, bp);
1698                         return;
1699                 }
1700
1701                 if (sc->sc_idle)
1702                         g_mirror_unidle(sc);
1703                 else
1704                         sc->sc_last_write = time_uptime;
1705
1706                 /*
1707                  * Bump syncid on first write.
1708                  */
1709                 if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID) != 0) {
1710                         sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID;
1711                         g_mirror_bump_syncid(sc);
1712                 }
1713
1714                 /*
1715                  * Allocate all bios before sending any request, so we can
1716                  * return ENOMEM in nice and clean way.
1717                  */
1718                 TAILQ_INIT(&queue);
1719                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1720                         switch (disk->d_state) {
1721                         case G_MIRROR_DISK_STATE_ACTIVE:
1722                                 break;
1723                         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
1724                                 if (bp->bio_offset >= disk->d_sync.ds_offset)
1725                                         continue;
1726                                 break;
1727                         default:
1728                                 continue;
1729                         }
1730                         if (bp->bio_cmd == BIO_DELETE &&
1731                             (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE) == 0)
1732                                 continue;
1733                         cbp = g_clone_bio(bp);
1734                         if (cbp == NULL) {
1735                                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1736                                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1737                                         g_destroy_bio(cbp);
1738                                 }
1739                                 if (bp->bio_error == 0)
1740                                         bp->bio_error = ENOMEM;
1741                                 g_io_deliver(bp, bp->bio_error);
1742                                 return;
1743                         }
1744                         TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1745                         cbp->bio_done = g_mirror_done;
1746                         cp = disk->d_consumer;
1747                         cbp->bio_caller1 = cp;
1748                         cbp->bio_to = cp->provider;
1749                         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1750                             ("Consumer %s not opened (r%dw%de%d).",
1751                             cp->provider->name, cp->acr, cp->acw, cp->ace));
1752                 }
1753                 if (TAILQ_EMPTY(&queue)) {
1754                         KASSERT(bp->bio_cmd == BIO_DELETE,
1755                             ("No consumers for regular request %p", bp));
1756                         g_io_deliver(bp, EOPNOTSUPP);
1757                         return;
1758                 }
1759                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1760                         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1761                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1762                         cp = cbp->bio_caller1;
1763                         cbp->bio_caller1 = NULL;
1764                         cp->index++;
1765                         sc->sc_writes++;
1766                         g_io_request(cbp, cp);
1767                 }
1768                 /*
1769                  * Put request onto inflight queue, so we can check if new
1770                  * synchronization requests don't collide with it.
1771                  */
1772                 TAILQ_INSERT_TAIL(&sc->sc_inflight, bp, bio_queue);
1773                 return;
1774         case BIO_FLUSH:
1775                 TAILQ_INIT(&queue);
1776                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1777                         if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1778                                 continue;
1779                         cbp = g_clone_bio(bp);
1780                         if (cbp == NULL) {
1781                                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1782                                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1783                                         g_destroy_bio(cbp);
1784                                 }
1785                                 if (bp->bio_error == 0)
1786                                         bp->bio_error = ENOMEM;
1787                                 g_io_deliver(bp, bp->bio_error);
1788                                 return;
1789                         }
1790                         TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1791                         cbp->bio_done = g_mirror_done;
1792                         cbp->bio_caller1 = disk;
1793                         cbp->bio_to = disk->d_consumer->provider;
1794                 }
1795                 KASSERT(!TAILQ_EMPTY(&queue),
1796                     ("No consumers for regular request %p", bp));
1797                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1798                         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1799                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1800                         disk = cbp->bio_caller1;
1801                         cbp->bio_caller1 = NULL;
1802                         cp = disk->d_consumer;
1803                         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1804                             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1805                             cp->acr, cp->acw, cp->ace));
1806                         cp->index++;
1807                         g_io_request(cbp, cp);
1808                 }
1809                 break;
1810         default:
1811                 KASSERT(1 == 0, ("Invalid command here: %u (device=%s)",
1812                     bp->bio_cmd, sc->sc_name));
1813                 break;
1814         }
1815 }
1816
1817 static int
1818 g_mirror_can_destroy(struct g_mirror_softc *sc)
1819 {
1820         struct g_geom *gp;
1821         struct g_consumer *cp;
1822
1823         g_topology_assert();
1824         gp = sc->sc_geom;
1825         if (gp->softc == NULL)
1826                 return (1);
1827         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_TASTING) != 0)
1828                 return (0);
1829         LIST_FOREACH(cp, &gp->consumer, consumer) {
1830                 if (g_mirror_is_busy(sc, cp))
1831                         return (0);
1832         }
1833         gp = sc->sc_sync.ds_geom;
1834         LIST_FOREACH(cp, &gp->consumer, consumer) {
1835                 if (g_mirror_is_busy(sc, cp))
1836                         return (0);
1837         }
1838         G_MIRROR_DEBUG(2, "No I/O requests for %s, it can be destroyed.",
1839             sc->sc_name);
1840         return (1);
1841 }
1842
1843 static int
1844 g_mirror_try_destroy(struct g_mirror_softc *sc)
1845 {
1846
1847         if (sc->sc_rootmount != NULL) {
1848                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p", __LINE__,
1849                     sc->sc_rootmount);
1850                 root_mount_rel(sc->sc_rootmount);
1851                 sc->sc_rootmount = NULL;
1852         }
1853         g_topology_lock();
1854         if (!g_mirror_can_destroy(sc)) {
1855                 g_topology_unlock();
1856                 return (0);
1857         }
1858         sc->sc_geom->softc = NULL;
1859         sc->sc_sync.ds_geom->softc = NULL;
1860         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DRAIN) != 0) {
1861                 g_topology_unlock();
1862                 G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__,
1863                     &sc->sc_worker);
1864                 /* Unlock sc_lock here, as it can be destroyed after wakeup. */
1865                 sx_xunlock(&sc->sc_lock);
1866                 wakeup(&sc->sc_worker);
1867                 sc->sc_worker = NULL;
1868         } else {
1869                 g_topology_unlock();
1870                 g_mirror_destroy_device(sc);
1871         }
1872         return (1);
1873 }
1874
1875 /*
1876  * Worker thread.
1877  */
1878 static void
1879 g_mirror_worker(void *arg)
1880 {
1881         struct g_mirror_softc *sc;
1882         struct g_mirror_event *ep;
1883         struct bio *bp;
1884         int timeout;
1885
1886         sc = arg;
1887         thread_lock(curthread);
1888         sched_prio(curthread, PRIBIO);
1889         thread_unlock(curthread);
1890
1891         sx_xlock(&sc->sc_lock);
1892         for (;;) {
1893                 G_MIRROR_DEBUG(5, "%s: Let's see...", __func__);
1894                 /*
1895                  * First take a look at events.
1896                  * This is important to handle events before any I/O requests.
1897                  */
1898                 ep = g_mirror_event_first(sc);
1899                 if (ep != NULL) {
1900                         g_mirror_event_remove(sc, ep);
1901                         if ((ep->e_flags & G_MIRROR_EVENT_DEVICE) != 0) {
1902                                 /* Update only device status. */
1903                                 G_MIRROR_DEBUG(3,
1904                                     "Running event for device %s.",
1905                                     sc->sc_name);
1906                                 ep->e_error = 0;
1907                                 g_mirror_update_device(sc, true);
1908                         } else {
1909                                 /* Update disk status. */
1910                                 G_MIRROR_DEBUG(3, "Running event for disk %s.",
1911                                      g_mirror_get_diskname(ep->e_disk));
1912                                 ep->e_error = g_mirror_update_disk(ep->e_disk,
1913                                     ep->e_state);
1914                                 if (ep->e_error == 0)
1915                                         g_mirror_update_device(sc, false);
1916                         }
1917                         if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0) {
1918                                 KASSERT(ep->e_error == 0,
1919                                     ("Error cannot be handled."));
1920                                 g_mirror_event_free(ep);
1921                         } else {
1922                                 ep->e_flags |= G_MIRROR_EVENT_DONE;
1923                                 G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__,
1924                                     ep);
1925                                 mtx_lock(&sc->sc_events_mtx);
1926                                 wakeup(ep);
1927                                 mtx_unlock(&sc->sc_events_mtx);
1928                         }
1929                         if ((sc->sc_flags &
1930                             G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1931                                 if (g_mirror_try_destroy(sc)) {
1932                                         curthread->td_pflags &= ~TDP_GEOM;
1933                                         G_MIRROR_DEBUG(1, "Thread exiting.");
1934                                         kproc_exit(0);
1935                                 }
1936                         }
1937                         G_MIRROR_DEBUG(5, "%s: I'm here 1.", __func__);
1938                         continue;
1939                 }
1940
1941                 /*
1942                  * Check if we can mark array as CLEAN and if we can't take
1943                  * how much seconds should we wait.
1944                  */
1945                 timeout = g_mirror_idle(sc, -1);
1946
1947                 /*
1948                  * Handle I/O requests.
1949                  */
1950                 mtx_lock(&sc->sc_queue_mtx);
1951                 bp = TAILQ_FIRST(&sc->sc_queue);
1952                 if (bp != NULL)
1953                         TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue);
1954                 else {
1955                         if ((sc->sc_flags &
1956                             G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1957                                 mtx_unlock(&sc->sc_queue_mtx);
1958                                 if (g_mirror_try_destroy(sc)) {
1959                                         curthread->td_pflags &= ~TDP_GEOM;
1960                                         G_MIRROR_DEBUG(1, "Thread exiting.");
1961                                         kproc_exit(0);
1962                                 }
1963                                 mtx_lock(&sc->sc_queue_mtx);
1964                                 if (!TAILQ_EMPTY(&sc->sc_queue)) {
1965                                         mtx_unlock(&sc->sc_queue_mtx);
1966                                         continue;
1967                                 }
1968                         }
1969                         if (g_mirror_event_first(sc) != NULL) {
1970                                 mtx_unlock(&sc->sc_queue_mtx);
1971                                 continue;
1972                         }
1973                         sx_xunlock(&sc->sc_lock);
1974                         MSLEEP(sc, &sc->sc_queue_mtx, PRIBIO | PDROP, "m:w1",
1975                             timeout * hz);
1976                         sx_xlock(&sc->sc_lock);
1977                         G_MIRROR_DEBUG(5, "%s: I'm here 4.", __func__);
1978                         continue;
1979                 }
1980                 mtx_unlock(&sc->sc_queue_mtx);
1981
1982                 if (bp->bio_from->geom == sc->sc_sync.ds_geom &&
1983                     (bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0) {
1984                         /*
1985                          * Handle completion of the first half (the read) of a
1986                          * block synchronization operation.
1987                          */
1988                         g_mirror_sync_request(sc, bp);
1989                 } else if (bp->bio_to != sc->sc_provider) {
1990                         if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_REGULAR) != 0)
1991                                 /*
1992                                  * Handle completion of a regular I/O request.
1993                                  */
1994                                 g_mirror_regular_request(sc, bp);
1995                         else if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0)
1996                                 /*
1997                                  * Handle completion of the second half (the
1998                                  * write) of a block synchronization operation.
1999                                  */
2000                                 g_mirror_sync_request(sc, bp);
2001                         else {
2002                                 KASSERT(0,
2003                                     ("Invalid request cflags=0x%hx to=%s.",
2004                                     bp->bio_cflags, bp->bio_to->name));
2005                         }
2006                 } else {
2007                         /*
2008                          * Initiate an I/O request.
2009                          */
2010                         g_mirror_register_request(sc, bp);
2011                 }
2012                 G_MIRROR_DEBUG(5, "%s: I'm here 9.", __func__);
2013         }
2014 }
2015
2016 static void
2017 g_mirror_update_idle(struct g_mirror_softc *sc, struct g_mirror_disk *disk)
2018 {
2019
2020         sx_assert(&sc->sc_lock, SX_LOCKED);
2021
2022         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
2023                 return;
2024         if (!sc->sc_idle && (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) == 0) {
2025                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as dirty.",
2026                     g_mirror_get_diskname(disk), sc->sc_name);
2027                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
2028         } else if (sc->sc_idle &&
2029             (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) != 0) {
2030                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as clean.",
2031                     g_mirror_get_diskname(disk), sc->sc_name);
2032                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2033         }
2034 }
2035
2036 static void
2037 g_mirror_sync_reinit(const struct g_mirror_disk *disk, struct bio *bp,
2038     off_t offset)
2039 {
2040         void *data;
2041         int idx;
2042
2043         data = bp->bio_data;
2044         idx = (int)(uintptr_t)bp->bio_caller1;
2045         g_reset_bio(bp);
2046
2047         bp->bio_cmd = BIO_READ;
2048         bp->bio_data = data;
2049         bp->bio_done = g_mirror_sync_done;
2050         bp->bio_from = disk->d_sync.ds_consumer;
2051         bp->bio_to = disk->d_softc->sc_provider;
2052         bp->bio_caller1 = (void *)(uintptr_t)idx;
2053         bp->bio_offset = offset;
2054         bp->bio_length = MIN(MAXPHYS,
2055             disk->d_softc->sc_mediasize - bp->bio_offset);
2056 }
2057
2058 static void
2059 g_mirror_sync_start(struct g_mirror_disk *disk)
2060 {
2061         struct g_mirror_softc *sc;
2062         struct g_mirror_disk_sync *sync;
2063         struct g_consumer *cp;
2064         struct bio *bp;
2065         int error, i;
2066
2067         g_topology_assert_not();
2068         sc = disk->d_softc;
2069         sync = &disk->d_sync;
2070         sx_assert(&sc->sc_lock, SX_LOCKED);
2071
2072         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2073             ("Disk %s is not marked for synchronization.",
2074             g_mirror_get_diskname(disk)));
2075         KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2076             ("Device not in RUNNING state (%s, %u).", sc->sc_name,
2077             sc->sc_state));
2078
2079         sx_xunlock(&sc->sc_lock);
2080         g_topology_lock();
2081         cp = g_new_consumer(sc->sc_sync.ds_geom);
2082         cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
2083         error = g_attach(cp, sc->sc_provider);
2084         KASSERT(error == 0,
2085             ("Cannot attach to %s (error=%d).", sc->sc_name, error));
2086         error = g_access(cp, 1, 0, 0);
2087         KASSERT(error == 0, ("Cannot open %s (error=%d).", sc->sc_name, error));
2088         g_topology_unlock();
2089         sx_xlock(&sc->sc_lock);
2090
2091         G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s.", sc->sc_name,
2092             g_mirror_get_diskname(disk));
2093         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) == 0)
2094                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
2095         KASSERT(sync->ds_consumer == NULL,
2096             ("Sync consumer already exists (device=%s, disk=%s).",
2097             sc->sc_name, g_mirror_get_diskname(disk)));
2098
2099         sync->ds_consumer = cp;
2100         sync->ds_consumer->private = disk;
2101         sync->ds_consumer->index = 0;
2102
2103         /*
2104          * Allocate memory for synchronization bios and initialize them.
2105          */
2106         sync->ds_bios = malloc(sizeof(struct bio *) * g_mirror_syncreqs,
2107             M_MIRROR, M_WAITOK);
2108         for (i = 0; i < g_mirror_syncreqs; i++) {
2109                 bp = g_alloc_bio();
2110                 sync->ds_bios[i] = bp;
2111
2112                 bp->bio_data = malloc(MAXPHYS, M_MIRROR, M_WAITOK);
2113                 bp->bio_caller1 = (void *)(uintptr_t)i;
2114                 g_mirror_sync_reinit(disk, bp, sync->ds_offset);
2115                 sync->ds_offset += bp->bio_length;
2116         }
2117
2118         /* Increase the number of disks in SYNCHRONIZING state. */
2119         sc->sc_sync.ds_ndisks++;
2120         /* Set the number of in-flight synchronization requests. */
2121         sync->ds_inflight = g_mirror_syncreqs;
2122
2123         /*
2124          * Fire off first synchronization requests.
2125          */
2126         for (i = 0; i < g_mirror_syncreqs; i++) {
2127                 bp = sync->ds_bios[i];
2128                 G_MIRROR_LOGREQ(3, bp, "Sending synchronization request.");
2129                 sync->ds_consumer->index++;
2130                 /*
2131                  * Delay the request if it is colliding with a regular request.
2132                  */
2133                 if (g_mirror_regular_collision(sc, bp))
2134                         g_mirror_sync_delay(sc, bp);
2135                 else
2136                         g_io_request(bp, sync->ds_consumer);
2137         }
2138 }
2139
2140 /*
2141  * Stop synchronization process.
2142  * type: 0 - synchronization finished
2143  *       1 - synchronization stopped
2144  */
2145 static void
2146 g_mirror_sync_stop(struct g_mirror_disk *disk, int type)
2147 {
2148         struct g_mirror_softc *sc;
2149         struct g_consumer *cp;
2150
2151         g_topology_assert_not();
2152         sc = disk->d_softc;
2153         sx_assert(&sc->sc_lock, SX_LOCKED);
2154
2155         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2156             ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2157             g_mirror_disk_state2str(disk->d_state)));
2158         if (disk->d_sync.ds_consumer == NULL)
2159                 return;
2160
2161         if (type == 0) {
2162                 G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s finished.",
2163                     sc->sc_name, g_mirror_get_diskname(disk));
2164         } else /* if (type == 1) */ {
2165                 G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s stopped.",
2166                     sc->sc_name, g_mirror_get_diskname(disk));
2167         }
2168         g_mirror_regular_release(sc);
2169         free(disk->d_sync.ds_bios, M_MIRROR);
2170         disk->d_sync.ds_bios = NULL;
2171         cp = disk->d_sync.ds_consumer;
2172         disk->d_sync.ds_consumer = NULL;
2173         disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2174         sc->sc_sync.ds_ndisks--;
2175         sx_xunlock(&sc->sc_lock); /* Avoid recursion on sc_lock. */
2176         g_topology_lock();
2177         g_mirror_kill_consumer(sc, cp);
2178         g_topology_unlock();
2179         sx_xlock(&sc->sc_lock);
2180 }
2181
2182 static void
2183 g_mirror_launch_provider(struct g_mirror_softc *sc)
2184 {
2185         struct g_mirror_disk *disk;
2186         struct g_provider *pp, *dp;
2187
2188         sx_assert(&sc->sc_lock, SX_LOCKED);
2189
2190         g_topology_lock();
2191         pp = g_new_providerf(sc->sc_geom, "mirror/%s", sc->sc_name);
2192         pp->flags |= G_PF_DIRECT_RECEIVE;
2193         pp->mediasize = sc->sc_mediasize;
2194         pp->sectorsize = sc->sc_sectorsize;
2195         pp->stripesize = 0;
2196         pp->stripeoffset = 0;
2197
2198         /* Splitting of unmapped BIO's could work but isn't implemented now */
2199         if (sc->sc_balance != G_MIRROR_BALANCE_SPLIT)
2200                 pp->flags |= G_PF_ACCEPT_UNMAPPED;
2201
2202         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2203                 if (disk->d_consumer && disk->d_consumer->provider) {
2204                         dp = disk->d_consumer->provider;
2205                         if (dp->stripesize > pp->stripesize) {
2206                                 pp->stripesize = dp->stripesize;
2207                                 pp->stripeoffset = dp->stripeoffset;
2208                         }
2209                         /* A provider underneath us doesn't support unmapped */
2210                         if ((dp->flags & G_PF_ACCEPT_UNMAPPED) == 0) {
2211                                 G_MIRROR_DEBUG(0, "Cancelling unmapped "
2212                                     "because of %s.", dp->name);
2213                                 pp->flags &= ~G_PF_ACCEPT_UNMAPPED;
2214                         }
2215                 }
2216         }
2217         pp->private = sc;
2218         sc->sc_refcnt++;
2219         sc->sc_provider = pp;
2220         g_error_provider(pp, 0);
2221         g_topology_unlock();
2222         G_MIRROR_DEBUG(0, "Device %s launched (%u/%u).", pp->name,
2223             g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE), sc->sc_ndisks);
2224         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2225                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
2226                         g_mirror_sync_start(disk);
2227         }
2228 }
2229
2230 static void
2231 g_mirror_destroy_provider(struct g_mirror_softc *sc)
2232 {
2233         struct g_mirror_disk *disk;
2234         struct bio *bp;
2235
2236         g_topology_assert_not();
2237         KASSERT(sc->sc_provider != NULL, ("NULL provider (device=%s).",
2238             sc->sc_name));
2239
2240         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2241                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
2242                         g_mirror_sync_stop(disk, 1);
2243         }
2244
2245         g_topology_lock();
2246         g_error_provider(sc->sc_provider, ENXIO);
2247         mtx_lock(&sc->sc_queue_mtx);
2248         while ((bp = TAILQ_FIRST(&sc->sc_queue)) != NULL) {
2249                 TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue);
2250                 /*
2251                  * Abort any pending I/O that wasn't generated by us.
2252                  * Synchronization requests and requests destined for individual
2253                  * mirror components can be destroyed immediately.
2254                  */
2255                 if (bp->bio_to == sc->sc_provider &&
2256                     bp->bio_from->geom != sc->sc_sync.ds_geom) {
2257                         g_io_deliver(bp, ENXIO);
2258                 } else {
2259                         if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0)
2260                                 free(bp->bio_data, M_MIRROR);
2261                         g_destroy_bio(bp);
2262                 }
2263         }
2264         mtx_unlock(&sc->sc_queue_mtx);
2265         g_wither_provider(sc->sc_provider, ENXIO);
2266         sc->sc_provider = NULL;
2267         G_MIRROR_DEBUG(0, "Device %s: provider destroyed.", sc->sc_name);
2268         g_topology_unlock();
2269 }
2270
2271 static void
2272 g_mirror_go(void *arg)
2273 {
2274         struct g_mirror_softc *sc;
2275
2276         sc = arg;
2277         G_MIRROR_DEBUG(0, "Force device %s start due to timeout.", sc->sc_name);
2278         g_mirror_event_send(sc, 0,
2279             G_MIRROR_EVENT_DONTWAIT | G_MIRROR_EVENT_DEVICE);
2280 }
2281
2282 static u_int
2283 g_mirror_determine_state(struct g_mirror_disk *disk)
2284 {
2285         struct g_mirror_softc *sc;
2286         u_int state;
2287
2288         sc = disk->d_softc;
2289         if (sc->sc_syncid == disk->d_sync.ds_syncid) {
2290                 if ((disk->d_flags &
2291                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) == 0 &&
2292                     (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 0 ||
2293                      (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) == 0)) {
2294                         /* Disk does not need synchronization. */
2295                         state = G_MIRROR_DISK_STATE_ACTIVE;
2296                 } else {
2297                         if ((sc->sc_flags &
2298                              G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) == 0 ||
2299                             (disk->d_flags &
2300                              G_MIRROR_DISK_FLAG_FORCE_SYNC) != 0) {
2301                                 /*
2302                                  * We can start synchronization from
2303                                  * the stored offset.
2304                                  */
2305                                 state = G_MIRROR_DISK_STATE_SYNCHRONIZING;
2306                         } else {
2307                                 state = G_MIRROR_DISK_STATE_STALE;
2308                         }
2309                 }
2310         } else if (disk->d_sync.ds_syncid < sc->sc_syncid) {
2311                 /*
2312                  * Reset all synchronization data for this disk,
2313                  * because if it even was synchronized, it was
2314                  * synchronized to disks with different syncid.
2315                  */
2316                 disk->d_flags |= G_MIRROR_DISK_FLAG_SYNCHRONIZING;
2317                 disk->d_sync.ds_offset = 0;
2318                 disk->d_sync.ds_offset_done = 0;
2319                 disk->d_sync.ds_syncid = sc->sc_syncid;
2320                 if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) == 0 ||
2321                     (disk->d_flags & G_MIRROR_DISK_FLAG_FORCE_SYNC) != 0) {
2322                         state = G_MIRROR_DISK_STATE_SYNCHRONIZING;
2323                 } else {
2324                         state = G_MIRROR_DISK_STATE_STALE;
2325                 }
2326         } else /* if (sc->sc_syncid < disk->d_sync.ds_syncid) */ {
2327                 /*
2328                  * Not good, NOT GOOD!
2329                  * It means that mirror was started on stale disks
2330                  * and more fresh disk just arrive.
2331                  * If there were writes, mirror is broken, sorry.
2332                  * I think the best choice here is don't touch
2333                  * this disk and inform the user loudly.
2334                  */
2335                 G_MIRROR_DEBUG(0, "Device %s was started before the freshest "
2336                     "disk (%s) arrives!! It will not be connected to the "
2337                     "running device.", sc->sc_name,
2338                     g_mirror_get_diskname(disk));
2339                 g_mirror_destroy_disk(disk);
2340                 state = G_MIRROR_DISK_STATE_NONE;
2341                 /* Return immediately, because disk was destroyed. */
2342                 return (state);
2343         }
2344         G_MIRROR_DEBUG(3, "State for %s disk: %s.",
2345             g_mirror_get_diskname(disk), g_mirror_disk_state2str(state));
2346         return (state);
2347 }
2348
2349 /*
2350  * Update device state.
2351  */
2352 static void
2353 g_mirror_update_device(struct g_mirror_softc *sc, bool force)
2354 {
2355         struct g_mirror_disk *disk;
2356         u_int state;
2357
2358         sx_assert(&sc->sc_lock, SX_XLOCKED);
2359
2360         switch (sc->sc_state) {
2361         case G_MIRROR_DEVICE_STATE_STARTING:
2362             {
2363                 struct g_mirror_disk *pdisk, *tdisk;
2364                 u_int dirty, ndisks, genid, syncid;
2365                 bool broken;
2366
2367                 KASSERT(sc->sc_provider == NULL,
2368                     ("Non-NULL provider in STARTING state (%s).", sc->sc_name));
2369                 /*
2370                  * Are we ready? We are, if all disks are connected or
2371                  * if we have any disks and 'force' is true.
2372                  */
2373                 ndisks = g_mirror_ndisks(sc, -1);
2374                 if (sc->sc_ndisks == ndisks || (force && ndisks > 0)) {
2375                         ;
2376                 } else if (ndisks == 0) {
2377                         /*
2378                          * Disks went down in starting phase, so destroy
2379                          * device.
2380                          */
2381                         callout_drain(&sc->sc_callout);
2382                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2383                         G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p", __LINE__,
2384                             sc->sc_rootmount);
2385                         root_mount_rel(sc->sc_rootmount);
2386                         sc->sc_rootmount = NULL;
2387                         return;
2388                 } else {
2389                         return;
2390                 }
2391
2392                 /*
2393                  * Activate all disks with the biggest syncid.
2394                  */
2395                 if (force) {
2396                         /*
2397                          * If 'force' is true, we have been called due to
2398                          * timeout, so don't bother canceling timeout.
2399                          */
2400                         ndisks = 0;
2401                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2402                                 if ((disk->d_flags &
2403                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) == 0) {
2404                                         ndisks++;
2405                                 }
2406                         }
2407                         if (ndisks == 0) {
2408                                 /* No valid disks found, destroy device. */
2409                                 sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2410                                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p",
2411                                     __LINE__, sc->sc_rootmount);
2412                                 root_mount_rel(sc->sc_rootmount);
2413                                 sc->sc_rootmount = NULL;
2414                                 return;
2415                         }
2416                 } else {
2417                         /* Cancel timeout. */
2418                         callout_drain(&sc->sc_callout);
2419                 }
2420
2421                 /*
2422                  * Find the biggest genid.
2423                  */
2424                 genid = 0;
2425                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2426                         if (disk->d_genid > genid)
2427                                 genid = disk->d_genid;
2428                 }
2429                 sc->sc_genid = genid;
2430                 /*
2431                  * Remove all disks without the biggest genid.
2432                  */
2433                 broken = false;
2434                 LIST_FOREACH_SAFE(disk, &sc->sc_disks, d_next, tdisk) {
2435                         if (disk->d_genid < genid) {
2436                                 G_MIRROR_DEBUG(0,
2437                                     "Component %s (device %s) broken, skipping.",
2438                                     g_mirror_get_diskname(disk), sc->sc_name);
2439                                 g_mirror_destroy_disk(disk);
2440                                 /*
2441                                  * Bump the syncid in case we discover a healthy
2442                                  * replacement disk after starting the mirror.
2443                                  */
2444                                 broken = true;
2445                         }
2446                 }
2447
2448                 /*
2449                  * Find the biggest syncid.
2450                  */
2451                 syncid = 0;
2452                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2453                         if (disk->d_sync.ds_syncid > syncid)
2454                                 syncid = disk->d_sync.ds_syncid;
2455                 }
2456
2457                 /*
2458                  * Here we need to look for dirty disks and if all disks
2459                  * with the biggest syncid are dirty, we have to choose
2460                  * one with the biggest priority and rebuild the rest.
2461                  */
2462                 /*
2463                  * Find the number of dirty disks with the biggest syncid.
2464                  * Find the number of disks with the biggest syncid.
2465                  * While here, find a disk with the biggest priority.
2466                  */
2467                 dirty = ndisks = 0;
2468                 pdisk = NULL;
2469                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2470                         if (disk->d_sync.ds_syncid != syncid)
2471                                 continue;
2472                         if ((disk->d_flags &
2473                             G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2474                                 continue;
2475                         }
2476                         ndisks++;
2477                         if ((disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) != 0) {
2478                                 dirty++;
2479                                 if (pdisk == NULL ||
2480                                     pdisk->d_priority < disk->d_priority) {
2481                                         pdisk = disk;
2482                                 }
2483                         }
2484                 }
2485                 if (dirty == 0) {
2486                         /* No dirty disks at all, great. */
2487                 } else if (dirty == ndisks) {
2488                         /*
2489                          * Force synchronization for all dirty disks except one
2490                          * with the biggest priority.
2491                          */
2492                         KASSERT(pdisk != NULL, ("pdisk == NULL"));
2493                         G_MIRROR_DEBUG(1, "Using disk %s (device %s) as a "
2494                             "master disk for synchronization.",
2495                             g_mirror_get_diskname(pdisk), sc->sc_name);
2496                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2497                                 if (disk->d_sync.ds_syncid != syncid)
2498                                         continue;
2499                                 if ((disk->d_flags &
2500                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2501                                         continue;
2502                                 }
2503                                 KASSERT((disk->d_flags &
2504                                     G_MIRROR_DISK_FLAG_DIRTY) != 0,
2505                                     ("Disk %s isn't marked as dirty.",
2506                                     g_mirror_get_diskname(disk)));
2507                                 /* Skip the disk with the biggest priority. */
2508                                 if (disk == pdisk)
2509                                         continue;
2510                                 disk->d_sync.ds_syncid = 0;
2511                         }
2512                 } else if (dirty < ndisks) {
2513                         /*
2514                          * Force synchronization for all dirty disks.
2515                          * We have some non-dirty disks.
2516                          */
2517                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2518                                 if (disk->d_sync.ds_syncid != syncid)
2519                                         continue;
2520                                 if ((disk->d_flags &
2521                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2522                                         continue;
2523                                 }
2524                                 if ((disk->d_flags &
2525                                     G_MIRROR_DISK_FLAG_DIRTY) == 0) {
2526                                         continue;
2527                                 }
2528                                 disk->d_sync.ds_syncid = 0;
2529                         }
2530                 }
2531
2532                 /* Reset hint. */
2533                 sc->sc_hint = NULL;
2534                 sc->sc_syncid = syncid;
2535                 if (force || broken) {
2536                         /* Remember to bump syncid on first write. */
2537                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2538                 }
2539                 state = G_MIRROR_DEVICE_STATE_RUNNING;
2540                 G_MIRROR_DEBUG(1, "Device %s state changed from %s to %s.",
2541                     sc->sc_name, g_mirror_device_state2str(sc->sc_state),
2542                     g_mirror_device_state2str(state));
2543                 sc->sc_state = state;
2544                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2545                         state = g_mirror_determine_state(disk);
2546                         g_mirror_event_send(disk, state,
2547                             G_MIRROR_EVENT_DONTWAIT);
2548                         if (state == G_MIRROR_DISK_STATE_STALE)
2549                                 sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2550                 }
2551                 break;
2552             }
2553         case G_MIRROR_DEVICE_STATE_RUNNING:
2554                 if (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 0 &&
2555                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_NEW) == 0) {
2556                         /*
2557                          * No usable disks, so destroy the device.
2558                          */
2559                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2560                         break;
2561                 } else if (g_mirror_ndisks(sc,
2562                     G_MIRROR_DISK_STATE_ACTIVE) > 0 &&
2563                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_NEW) == 0) {
2564                         /*
2565                          * We have active disks, launch provider if it doesn't
2566                          * exist.
2567                          */
2568                         if (sc->sc_provider == NULL)
2569                                 g_mirror_launch_provider(sc);
2570                         if (sc->sc_rootmount != NULL) {
2571                                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p",
2572                                     __LINE__, sc->sc_rootmount);
2573                                 root_mount_rel(sc->sc_rootmount);
2574                                 sc->sc_rootmount = NULL;
2575                         }
2576                 }
2577                 /*
2578                  * Genid should be bumped immediately, so do it here.
2579                  */
2580                 if ((sc->sc_bump_id & G_MIRROR_BUMP_GENID) != 0) {
2581                         sc->sc_bump_id &= ~G_MIRROR_BUMP_GENID;
2582                         g_mirror_bump_genid(sc);
2583                 }
2584                 if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID_NOW) != 0) {
2585                         sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID_NOW;
2586                         g_mirror_bump_syncid(sc);
2587                 }
2588                 break;
2589         default:
2590                 KASSERT(1 == 0, ("Wrong device state (%s, %s).",
2591                     sc->sc_name, g_mirror_device_state2str(sc->sc_state)));
2592                 break;
2593         }
2594 }
2595
2596 /*
2597  * Update disk state and device state if needed.
2598  */
2599 #define DISK_STATE_CHANGED()    G_MIRROR_DEBUG(1,                       \
2600         "Disk %s state changed from %s to %s (device %s).",             \
2601         g_mirror_get_diskname(disk),                                    \
2602         g_mirror_disk_state2str(disk->d_state),                         \
2603         g_mirror_disk_state2str(state), sc->sc_name)
2604 static int
2605 g_mirror_update_disk(struct g_mirror_disk *disk, u_int state)
2606 {
2607         struct g_mirror_softc *sc;
2608
2609         sc = disk->d_softc;
2610         sx_assert(&sc->sc_lock, SX_XLOCKED);
2611
2612 again:
2613         G_MIRROR_DEBUG(3, "Changing disk %s state from %s to %s.",
2614             g_mirror_get_diskname(disk), g_mirror_disk_state2str(disk->d_state),
2615             g_mirror_disk_state2str(state));
2616         switch (state) {
2617         case G_MIRROR_DISK_STATE_NEW:
2618                 /*
2619                  * Possible scenarios:
2620                  * 1. New disk arrive.
2621                  */
2622                 /* Previous state should be NONE. */
2623                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NONE,
2624                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2625                     g_mirror_disk_state2str(disk->d_state)));
2626                 DISK_STATE_CHANGED();
2627
2628                 disk->d_state = state;
2629                 if (LIST_EMPTY(&sc->sc_disks))
2630                         LIST_INSERT_HEAD(&sc->sc_disks, disk, d_next);
2631                 else {
2632                         struct g_mirror_disk *dp;
2633
2634                         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
2635                                 if (disk->d_priority >= dp->d_priority) {
2636                                         LIST_INSERT_BEFORE(dp, disk, d_next);
2637                                         dp = NULL;
2638                                         break;
2639                                 }
2640                                 if (LIST_NEXT(dp, d_next) == NULL)
2641                                         break;
2642                         }
2643                         if (dp != NULL)
2644                                 LIST_INSERT_AFTER(dp, disk, d_next);
2645                 }
2646                 G_MIRROR_DEBUG(1, "Device %s: provider %s detected.",
2647                     sc->sc_name, g_mirror_get_diskname(disk));
2648                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING)
2649                         break;
2650                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2651                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2652                     g_mirror_device_state2str(sc->sc_state),
2653                     g_mirror_get_diskname(disk),
2654                     g_mirror_disk_state2str(disk->d_state)));
2655                 state = g_mirror_determine_state(disk);
2656                 if (state != G_MIRROR_DISK_STATE_NONE)
2657                         goto again;
2658                 break;
2659         case G_MIRROR_DISK_STATE_ACTIVE:
2660                 /*
2661                  * Possible scenarios:
2662                  * 1. New disk does not need synchronization.
2663                  * 2. Synchronization process finished successfully.
2664                  */
2665                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2666                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2667                     g_mirror_device_state2str(sc->sc_state),
2668                     g_mirror_get_diskname(disk),
2669                     g_mirror_disk_state2str(disk->d_state)));
2670                 /* Previous state should be NEW or SYNCHRONIZING. */
2671                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW ||
2672                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2673                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2674                     g_mirror_disk_state2str(disk->d_state)));
2675                 DISK_STATE_CHANGED();
2676
2677                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
2678                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_SYNCHRONIZING;
2679                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_FORCE_SYNC;
2680                         g_mirror_sync_stop(disk, 0);
2681                 }
2682                 disk->d_state = state;
2683                 disk->d_sync.ds_offset = 0;
2684                 disk->d_sync.ds_offset_done = 0;
2685                 g_mirror_update_idle(sc, disk);
2686                 g_mirror_update_metadata(disk);
2687                 G_MIRROR_DEBUG(1, "Device %s: provider %s activated.",
2688                     sc->sc_name, g_mirror_get_diskname(disk));
2689                 break;
2690         case G_MIRROR_DISK_STATE_STALE:
2691                 /*
2692                  * Possible scenarios:
2693                  * 1. Stale disk was connected.
2694                  */
2695                 /* Previous state should be NEW. */
2696                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2697                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2698                     g_mirror_disk_state2str(disk->d_state)));
2699                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2700                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2701                     g_mirror_device_state2str(sc->sc_state),
2702                     g_mirror_get_diskname(disk),
2703                     g_mirror_disk_state2str(disk->d_state)));
2704                 /*
2705                  * STALE state is only possible if device is marked
2706                  * NOAUTOSYNC.
2707                  */
2708                 KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) != 0,
2709                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2710                     g_mirror_device_state2str(sc->sc_state),
2711                     g_mirror_get_diskname(disk),
2712                     g_mirror_disk_state2str(disk->d_state)));
2713                 DISK_STATE_CHANGED();
2714
2715                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2716                 disk->d_state = state;
2717                 g_mirror_update_metadata(disk);
2718                 G_MIRROR_DEBUG(0, "Device %s: provider %s is stale.",
2719                     sc->sc_name, g_mirror_get_diskname(disk));
2720                 break;
2721         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
2722                 /*
2723                  * Possible scenarios:
2724                  * 1. Disk which needs synchronization was connected.
2725                  */
2726                 /* Previous state should be NEW. */
2727                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2728                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2729                     g_mirror_disk_state2str(disk->d_state)));
2730                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2731                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2732                     g_mirror_device_state2str(sc->sc_state),
2733                     g_mirror_get_diskname(disk),
2734                     g_mirror_disk_state2str(disk->d_state)));
2735                 DISK_STATE_CHANGED();
2736
2737                 if (disk->d_state == G_MIRROR_DISK_STATE_NEW)
2738                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2739                 disk->d_state = state;
2740                 if (sc->sc_provider != NULL) {
2741                         g_mirror_sync_start(disk);
2742                         g_mirror_update_metadata(disk);
2743                 }
2744                 break;
2745         case G_MIRROR_DISK_STATE_DISCONNECTED:
2746                 /*
2747                  * Possible scenarios:
2748                  * 1. Device wasn't running yet, but disk disappear.
2749                  * 2. Disk was active and disapppear.
2750                  * 3. Disk disappear during synchronization process.
2751                  */
2752                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING) {
2753                         /*
2754                          * Previous state should be ACTIVE, STALE or
2755                          * SYNCHRONIZING.
2756                          */
2757                         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
2758                             disk->d_state == G_MIRROR_DISK_STATE_STALE ||
2759                             disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2760                             ("Wrong disk state (%s, %s).",
2761                             g_mirror_get_diskname(disk),
2762                             g_mirror_disk_state2str(disk->d_state)));
2763                 } else if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING) {
2764                         /* Previous state should be NEW. */
2765                         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2766                             ("Wrong disk state (%s, %s).",
2767                             g_mirror_get_diskname(disk),
2768                             g_mirror_disk_state2str(disk->d_state)));
2769                         /*
2770                          * Reset bumping syncid if disk disappeared in STARTING
2771                          * state.
2772                          */
2773                         if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID) != 0)
2774                                 sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID;
2775 #ifdef  INVARIANTS
2776                 } else {
2777                         KASSERT(1 == 0, ("Wrong device state (%s, %s, %s, %s).",
2778                             sc->sc_name,
2779                             g_mirror_device_state2str(sc->sc_state),
2780                             g_mirror_get_diskname(disk),
2781                             g_mirror_disk_state2str(disk->d_state)));
2782 #endif
2783                 }
2784                 DISK_STATE_CHANGED();
2785                 G_MIRROR_DEBUG(0, "Device %s: provider %s disconnected.",
2786                     sc->sc_name, g_mirror_get_diskname(disk));
2787
2788                 g_mirror_destroy_disk(disk);
2789                 break;
2790         case G_MIRROR_DISK_STATE_DESTROY:
2791             {
2792                 int error;
2793
2794                 error = g_mirror_clear_metadata(disk);
2795                 if (error != 0) {
2796                         G_MIRROR_DEBUG(0,
2797                             "Device %s: failed to clear metadata on %s: %d.",
2798                             sc->sc_name, g_mirror_get_diskname(disk), error);
2799                         break;
2800                 }
2801                 DISK_STATE_CHANGED();
2802                 G_MIRROR_DEBUG(0, "Device %s: provider %s destroyed.",
2803                     sc->sc_name, g_mirror_get_diskname(disk));
2804
2805                 g_mirror_destroy_disk(disk);
2806                 sc->sc_ndisks--;
2807                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2808                         g_mirror_update_metadata(disk);
2809                 }
2810                 break;
2811             }
2812         default:
2813                 KASSERT(1 == 0, ("Unknown state (%u).", state));
2814                 break;
2815         }
2816         return (0);
2817 }
2818 #undef  DISK_STATE_CHANGED
2819
2820 int
2821 g_mirror_read_metadata(struct g_consumer *cp, struct g_mirror_metadata *md)
2822 {
2823         struct g_provider *pp;
2824         u_char *buf;
2825         int error;
2826
2827         g_topology_assert();
2828
2829         error = g_access(cp, 1, 0, 0);
2830         if (error != 0)
2831                 return (error);
2832         pp = cp->provider;
2833         g_topology_unlock();
2834         /* Metadata are stored on last sector. */
2835         buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
2836             &error);
2837         g_topology_lock();
2838         g_access(cp, -1, 0, 0);
2839         if (buf == NULL) {
2840                 G_MIRROR_DEBUG(1, "Cannot read metadata from %s (error=%d).",
2841                     cp->provider->name, error);
2842                 return (error);
2843         }
2844
2845         /* Decode metadata. */
2846         error = mirror_metadata_decode(buf, md);
2847         g_free(buf);
2848         if (strcmp(md->md_magic, G_MIRROR_MAGIC) != 0)
2849                 return (EINVAL);
2850         if (md->md_version > G_MIRROR_VERSION) {
2851                 G_MIRROR_DEBUG(0,
2852                     "Kernel module is too old to handle metadata from %s.",
2853                     cp->provider->name);
2854                 return (EINVAL);
2855         }
2856         if (error != 0) {
2857                 G_MIRROR_DEBUG(1, "MD5 metadata hash mismatch for provider %s.",
2858                     cp->provider->name);
2859                 return (error);
2860         }
2861
2862         return (0);
2863 }
2864
2865 static int
2866 g_mirror_check_metadata(struct g_mirror_softc *sc, struct g_provider *pp,
2867     struct g_mirror_metadata *md)
2868 {
2869
2870         if (g_mirror_id2disk(sc, md->md_did) != NULL) {
2871                 G_MIRROR_DEBUG(1, "Disk %s (id=%u) already exists, skipping.",
2872                     pp->name, md->md_did);
2873                 return (EEXIST);
2874         }
2875         if (md->md_all != sc->sc_ndisks) {
2876                 G_MIRROR_DEBUG(1,
2877                     "Invalid '%s' field on disk %s (device %s), skipping.",
2878                     "md_all", pp->name, sc->sc_name);
2879                 return (EINVAL);
2880         }
2881         if (md->md_slice != sc->sc_slice) {
2882                 G_MIRROR_DEBUG(1,
2883                     "Invalid '%s' field on disk %s (device %s), skipping.",
2884                     "md_slice", pp->name, sc->sc_name);
2885                 return (EINVAL);
2886         }
2887         if (md->md_balance != sc->sc_balance) {
2888                 G_MIRROR_DEBUG(1,
2889                     "Invalid '%s' field on disk %s (device %s), skipping.",
2890                     "md_balance", pp->name, sc->sc_name);
2891                 return (EINVAL);
2892         }
2893 #if 0
2894         if (md->md_mediasize != sc->sc_mediasize) {
2895                 G_MIRROR_DEBUG(1,
2896                     "Invalid '%s' field on disk %s (device %s), skipping.",
2897                     "md_mediasize", pp->name, sc->sc_name);
2898                 return (EINVAL);
2899         }
2900 #endif
2901         if (sc->sc_mediasize > pp->mediasize) {
2902                 G_MIRROR_DEBUG(1,
2903                     "Invalid size of disk %s (device %s), skipping.", pp->name,
2904                     sc->sc_name);
2905                 return (EINVAL);
2906         }
2907         if (md->md_sectorsize != sc->sc_sectorsize) {
2908                 G_MIRROR_DEBUG(1,
2909                     "Invalid '%s' field on disk %s (device %s), skipping.",
2910                     "md_sectorsize", pp->name, sc->sc_name);
2911                 return (EINVAL);
2912         }
2913         if ((sc->sc_sectorsize % pp->sectorsize) != 0) {
2914                 G_MIRROR_DEBUG(1,
2915                     "Invalid sector size of disk %s (device %s), skipping.",
2916                     pp->name, sc->sc_name);
2917                 return (EINVAL);
2918         }
2919         if ((md->md_mflags & ~G_MIRROR_DEVICE_FLAG_MASK) != 0) {
2920                 G_MIRROR_DEBUG(1,
2921                     "Invalid device flags on disk %s (device %s), skipping.",
2922                     pp->name, sc->sc_name);
2923                 return (EINVAL);
2924         }
2925         if ((md->md_dflags & ~G_MIRROR_DISK_FLAG_MASK) != 0) {
2926                 G_MIRROR_DEBUG(1,
2927                     "Invalid disk flags on disk %s (device %s), skipping.",
2928                     pp->name, sc->sc_name);
2929                 return (EINVAL);
2930         }
2931         return (0);
2932 }
2933
2934 int
2935 g_mirror_add_disk(struct g_mirror_softc *sc, struct g_provider *pp,
2936     struct g_mirror_metadata *md)
2937 {
2938         struct g_mirror_disk *disk;
2939         int error;
2940
2941         g_topology_assert_not();
2942         G_MIRROR_DEBUG(2, "Adding disk %s.", pp->name);
2943
2944         error = g_mirror_check_metadata(sc, pp, md);
2945         if (error != 0)
2946                 return (error);
2947         if (sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING &&
2948             md->md_genid < sc->sc_genid) {
2949                 G_MIRROR_DEBUG(0, "Component %s (device %s) broken, skipping.",
2950                     pp->name, sc->sc_name);
2951                 return (EINVAL);
2952         }
2953         disk = g_mirror_init_disk(sc, pp, md, &error);
2954         if (disk == NULL)
2955                 return (error);
2956         error = g_mirror_event_send(disk, G_MIRROR_DISK_STATE_NEW,
2957             G_MIRROR_EVENT_WAIT);
2958         if (error != 0)
2959                 return (error);
2960         if (md->md_version < G_MIRROR_VERSION) {
2961                 G_MIRROR_DEBUG(0, "Upgrading metadata on %s (v%d->v%d).",
2962                     pp->name, md->md_version, G_MIRROR_VERSION);
2963                 g_mirror_update_metadata(disk);
2964         }
2965         return (0);
2966 }
2967
2968 static void
2969 g_mirror_destroy_delayed(void *arg, int flag)
2970 {
2971         struct g_mirror_softc *sc;
2972         int error;
2973
2974         if (flag == EV_CANCEL) {
2975                 G_MIRROR_DEBUG(1, "Destroying canceled.");
2976                 return;
2977         }
2978         sc = arg;
2979         g_topology_unlock();
2980         sx_xlock(&sc->sc_lock);
2981         KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) == 0,
2982             ("DESTROY flag set on %s.", sc->sc_name));
2983         KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0,
2984             ("CLOSEWAIT flag not set on %s.", sc->sc_name));
2985         G_MIRROR_DEBUG(1, "Destroying %s (delayed).", sc->sc_name);
2986         error = g_mirror_destroy(sc, G_MIRROR_DESTROY_SOFT);
2987         if (error != 0) {
2988                 G_MIRROR_DEBUG(0, "Cannot destroy %s (error=%d).",
2989                     sc->sc_name, error);
2990                 sx_xunlock(&sc->sc_lock);
2991         }
2992         g_topology_lock();
2993 }
2994
2995 static int
2996 g_mirror_access(struct g_provider *pp, int acr, int acw, int ace)
2997 {
2998         struct g_mirror_softc *sc;
2999         int error = 0;
3000
3001         g_topology_assert();
3002         G_MIRROR_DEBUG(2, "Access request for %s: r%dw%de%d.", pp->name, acr,
3003             acw, ace);
3004
3005         sc = pp->private;
3006         KASSERT(sc != NULL, ("NULL softc (provider=%s).", pp->name));
3007
3008         g_topology_unlock();
3009         sx_xlock(&sc->sc_lock);
3010         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0 ||
3011             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0 ||
3012             LIST_EMPTY(&sc->sc_disks)) {
3013                 if (acr > 0 || acw > 0 || ace > 0)
3014                         error = ENXIO;
3015                 goto end;
3016         }
3017         sc->sc_provider_open += acr + acw + ace;
3018         if (pp->acw + acw == 0)
3019                 g_mirror_idle(sc, 0);
3020         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0 &&
3021             sc->sc_provider_open == 0)
3022                 g_post_event(g_mirror_destroy_delayed, sc, M_WAITOK, sc, NULL);
3023 end:
3024         sx_xunlock(&sc->sc_lock);
3025         g_topology_lock();
3026         return (error);
3027 }
3028
3029 struct g_geom *
3030 g_mirror_create(struct g_class *mp, const struct g_mirror_metadata *md,
3031     u_int type)
3032 {
3033         struct g_mirror_softc *sc;
3034         struct g_geom *gp;
3035         int error, timeout;
3036
3037         g_topology_assert();
3038         G_MIRROR_DEBUG(1, "Creating device %s (id=%u).", md->md_name,
3039             md->md_mid);
3040
3041         /* One disk is minimum. */
3042         if (md->md_all < 1)
3043                 return (NULL);
3044         /*
3045          * Action geom.
3046          */
3047         gp = g_new_geomf(mp, "%s", md->md_name);
3048         sc = malloc(sizeof(*sc), M_MIRROR, M_WAITOK | M_ZERO);
3049         gp->start = g_mirror_start;
3050         gp->orphan = g_mirror_orphan;
3051         gp->access = g_mirror_access;
3052         gp->dumpconf = g_mirror_dumpconf;
3053
3054         sc->sc_type = type;
3055         sc->sc_id = md->md_mid;
3056         sc->sc_slice = md->md_slice;
3057         sc->sc_balance = md->md_balance;
3058         sc->sc_mediasize = md->md_mediasize;
3059         sc->sc_sectorsize = md->md_sectorsize;
3060         sc->sc_ndisks = md->md_all;
3061         sc->sc_flags = md->md_mflags;
3062         sc->sc_bump_id = 0;
3063         sc->sc_idle = 1;
3064         sc->sc_last_write = time_uptime;
3065         sc->sc_writes = 0;
3066         sc->sc_refcnt = 1;
3067         sx_init(&sc->sc_lock, "gmirror:lock");
3068         TAILQ_INIT(&sc->sc_queue);
3069         mtx_init(&sc->sc_queue_mtx, "gmirror:queue", NULL, MTX_DEF);
3070         TAILQ_INIT(&sc->sc_regular_delayed);
3071         TAILQ_INIT(&sc->sc_inflight);
3072         TAILQ_INIT(&sc->sc_sync_delayed);
3073         LIST_INIT(&sc->sc_disks);
3074         TAILQ_INIT(&sc->sc_events);
3075         mtx_init(&sc->sc_events_mtx, "gmirror:events", NULL, MTX_DEF);
3076         callout_init(&sc->sc_callout, 1);
3077         mtx_init(&sc->sc_done_mtx, "gmirror:done", NULL, MTX_DEF);
3078         sc->sc_state = G_MIRROR_DEVICE_STATE_STARTING;
3079         gp->softc = sc;
3080         sc->sc_geom = gp;
3081         sc->sc_provider = NULL;
3082         sc->sc_provider_open = 0;
3083         /*
3084          * Synchronization geom.
3085          */
3086         gp = g_new_geomf(mp, "%s.sync", md->md_name);
3087         gp->softc = sc;
3088         gp->orphan = g_mirror_orphan;
3089         sc->sc_sync.ds_geom = gp;
3090         sc->sc_sync.ds_ndisks = 0;
3091         error = kproc_create(g_mirror_worker, sc, &sc->sc_worker, 0, 0,
3092             "g_mirror %s", md->md_name);
3093         if (error != 0) {
3094                 G_MIRROR_DEBUG(1, "Cannot create kernel thread for %s.",
3095                     sc->sc_name);
3096                 g_destroy_geom(sc->sc_sync.ds_geom);
3097                 g_destroy_geom(sc->sc_geom);
3098                 g_mirror_free_device(sc);
3099                 return (NULL);
3100         }
3101
3102         G_MIRROR_DEBUG(1, "Device %s created (%u components, id=%u).",
3103             sc->sc_name, sc->sc_ndisks, sc->sc_id);
3104
3105         sc->sc_rootmount = root_mount_hold("GMIRROR");
3106         G_MIRROR_DEBUG(1, "root_mount_hold %p", sc->sc_rootmount);
3107         /*
3108          * Run timeout.
3109          */
3110         timeout = g_mirror_timeout * hz;
3111         callout_reset(&sc->sc_callout, timeout, g_mirror_go, sc);
3112         return (sc->sc_geom);
3113 }
3114
3115 int
3116 g_mirror_destroy(struct g_mirror_softc *sc, int how)
3117 {
3118         struct g_mirror_disk *disk;
3119
3120         g_topology_assert_not();
3121         sx_assert(&sc->sc_lock, SX_XLOCKED);
3122
3123         if (sc->sc_provider_open != 0) {
3124                 switch (how) {
3125                 case G_MIRROR_DESTROY_SOFT:
3126                         G_MIRROR_DEBUG(1,
3127                             "Device %s is still open (%d).", sc->sc_name,
3128                             sc->sc_provider_open);
3129                         return (EBUSY);
3130                 case G_MIRROR_DESTROY_DELAYED:
3131                         G_MIRROR_DEBUG(1,
3132                             "Device %s will be destroyed on last close.",
3133                             sc->sc_name);
3134                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
3135                                 if (disk->d_state ==
3136                                     G_MIRROR_DISK_STATE_SYNCHRONIZING) {
3137                                         g_mirror_sync_stop(disk, 1);
3138                                 }
3139                         }
3140                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_CLOSEWAIT;
3141                         return (EBUSY);
3142                 case G_MIRROR_DESTROY_HARD:
3143                         G_MIRROR_DEBUG(1, "Device %s is still open, so it "
3144                             "can't be definitely removed.", sc->sc_name);
3145                 }
3146         }
3147
3148         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
3149                 sx_xunlock(&sc->sc_lock);
3150                 return (0);
3151         }
3152         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
3153         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DRAIN;
3154         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
3155         sx_xunlock(&sc->sc_lock);
3156         mtx_lock(&sc->sc_queue_mtx);
3157         wakeup(sc);
3158         mtx_unlock(&sc->sc_queue_mtx);
3159         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, &sc->sc_worker);
3160         while (sc->sc_worker != NULL)
3161                 tsleep(&sc->sc_worker, PRIBIO, "m:destroy", hz / 5);
3162         G_MIRROR_DEBUG(4, "%s: Woken up %p.", __func__, &sc->sc_worker);
3163         sx_xlock(&sc->sc_lock);
3164         g_mirror_destroy_device(sc);
3165         return (0);
3166 }
3167
3168 static void
3169 g_mirror_taste_orphan(struct g_consumer *cp)
3170 {
3171
3172         KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
3173             cp->provider->name));
3174 }
3175
3176 static struct g_geom *
3177 g_mirror_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
3178 {
3179         struct g_mirror_metadata md;
3180         struct g_mirror_softc *sc;
3181         struct g_consumer *cp;
3182         struct g_geom *gp;
3183         int error;
3184
3185         g_topology_assert();
3186         g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
3187         G_MIRROR_DEBUG(2, "Tasting %s.", pp->name);
3188
3189         gp = g_new_geomf(mp, "mirror:taste");
3190         /*
3191          * This orphan function should be never called.
3192          */
3193         gp->orphan = g_mirror_taste_orphan;
3194         cp = g_new_consumer(gp);
3195         g_attach(cp, pp);
3196         error = g_mirror_read_metadata(cp, &md);
3197         g_detach(cp);
3198         g_destroy_consumer(cp);
3199         g_destroy_geom(gp);
3200         if (error != 0)
3201                 return (NULL);
3202         gp = NULL;
3203
3204         if (md.md_provider[0] != '\0' &&
3205             !g_compare_names(md.md_provider, pp->name))
3206                 return (NULL);
3207         if (md.md_provsize != 0 && md.md_provsize != pp->mediasize)
3208                 return (NULL);
3209         if ((md.md_dflags & G_MIRROR_DISK_FLAG_INACTIVE) != 0) {
3210                 G_MIRROR_DEBUG(0,
3211                     "Device %s: provider %s marked as inactive, skipping.",
3212                     md.md_name, pp->name);
3213                 return (NULL);
3214         }
3215         if (g_mirror_debug >= 2)
3216                 mirror_metadata_dump(&md);
3217
3218         /*
3219          * Let's check if device already exists.
3220          */
3221         sc = NULL;
3222         LIST_FOREACH(gp, &mp->geom, geom) {
3223                 sc = gp->softc;
3224                 if (sc == NULL)
3225                         continue;
3226                 if (sc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
3227                         continue;
3228                 if (sc->sc_sync.ds_geom == gp)
3229                         continue;
3230                 if (strcmp(md.md_name, sc->sc_name) != 0)
3231                         continue;
3232                 if (md.md_mid != sc->sc_id) {
3233                         G_MIRROR_DEBUG(0, "Device %s already configured.",
3234                             sc->sc_name);
3235                         return (NULL);
3236                 }
3237                 break;
3238         }
3239         if (gp == NULL) {
3240                 gp = g_mirror_create(mp, &md, G_MIRROR_TYPE_AUTOMATIC);
3241                 if (gp == NULL) {
3242                         G_MIRROR_DEBUG(0, "Cannot create device %s.",
3243                             md.md_name);
3244                         return (NULL);
3245                 }
3246                 sc = gp->softc;
3247         }
3248         G_MIRROR_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
3249         g_topology_unlock();
3250         sx_xlock(&sc->sc_lock);
3251         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_TASTING;
3252         error = g_mirror_add_disk(sc, pp, &md);
3253         if (error != 0) {
3254                 G_MIRROR_DEBUG(0, "Cannot add disk %s to %s (error=%d).",
3255                     pp->name, gp->name, error);
3256                 if (LIST_EMPTY(&sc->sc_disks)) {
3257                         g_cancel_event(sc);
3258                         g_mirror_destroy(sc, G_MIRROR_DESTROY_HARD);
3259                         g_topology_lock();
3260                         return (NULL);
3261                 }
3262                 gp = NULL;
3263         }
3264         sc->sc_flags &= ~G_MIRROR_DEVICE_FLAG_TASTING;
3265         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
3266                 g_mirror_destroy(sc, G_MIRROR_DESTROY_HARD);
3267                 g_topology_lock();
3268                 return (NULL);
3269         }
3270         sx_xunlock(&sc->sc_lock);
3271         g_topology_lock();
3272         return (gp);
3273 }
3274
3275 static void
3276 g_mirror_resize(struct g_consumer *cp)
3277 {
3278         struct g_mirror_disk *disk;
3279
3280         g_topology_assert();
3281         g_trace(G_T_TOPOLOGY, "%s(%s)", __func__, cp->provider->name);
3282
3283         disk = cp->private;
3284         if (disk == NULL)
3285                 return;
3286         g_topology_unlock();
3287         g_mirror_update_metadata(disk);
3288         g_topology_lock();
3289 }
3290
3291 static int
3292 g_mirror_destroy_geom(struct gctl_req *req __unused,
3293     struct g_class *mp __unused, struct g_geom *gp)
3294 {
3295         struct g_mirror_softc *sc;
3296         int error;
3297
3298         g_topology_unlock();
3299         sc = gp->softc;
3300         sx_xlock(&sc->sc_lock);
3301         g_cancel_event(sc);
3302         error = g_mirror_destroy(gp->softc, G_MIRROR_DESTROY_SOFT);
3303         if (error != 0)
3304                 sx_xunlock(&sc->sc_lock);
3305         g_topology_lock();
3306         return (error);
3307 }
3308
3309 static void
3310 g_mirror_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
3311     struct g_consumer *cp, struct g_provider *pp)
3312 {
3313         struct g_mirror_softc *sc;
3314
3315         g_topology_assert();
3316
3317         sc = gp->softc;
3318         if (sc == NULL)
3319                 return;
3320         /* Skip synchronization geom. */
3321         if (gp == sc->sc_sync.ds_geom)
3322                 return;
3323         if (pp != NULL) {
3324                 /* Nothing here. */
3325         } else if (cp != NULL) {
3326                 struct g_mirror_disk *disk;
3327
3328                 disk = cp->private;
3329                 if (disk == NULL)
3330                         return;
3331                 g_topology_unlock();
3332                 sx_xlock(&sc->sc_lock);
3333                 sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)disk->d_id);
3334                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
3335                         sbuf_printf(sb, "%s<Synchronized>", indent);
3336                         if (disk->d_sync.ds_offset == 0)
3337                                 sbuf_printf(sb, "0%%");
3338                         else {
3339                                 sbuf_printf(sb, "%u%%",
3340                                     (u_int)((disk->d_sync.ds_offset * 100) /
3341                                     sc->sc_provider->mediasize));
3342                         }
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                 }
3350                 sbuf_printf(sb, "%s<SyncID>%u</SyncID>\n", indent,
3351                     disk->d_sync.ds_syncid);
3352                 sbuf_printf(sb, "%s<GenID>%u</GenID>\n", indent,
3353                     disk->d_genid);
3354                 sbuf_printf(sb, "%s<Flags>", indent);
3355                 if (disk->d_flags == 0)
3356                         sbuf_printf(sb, "NONE");
3357                 else {
3358                         int first = 1;
3359
3360 #define ADD_FLAG(flag, name)    do {                                    \
3361         if ((disk->d_flags & (flag)) != 0) {                            \
3362                 if (!first)                                             \
3363                         sbuf_printf(sb, ", ");                          \
3364                 else                                                    \
3365                         first = 0;                                      \
3366                 sbuf_printf(sb, name);                                  \
3367         }                                                               \
3368 } while (0)
3369                         ADD_FLAG(G_MIRROR_DISK_FLAG_DIRTY, "DIRTY");
3370                         ADD_FLAG(G_MIRROR_DISK_FLAG_HARDCODED, "HARDCODED");
3371                         ADD_FLAG(G_MIRROR_DISK_FLAG_INACTIVE, "INACTIVE");
3372                         ADD_FLAG(G_MIRROR_DISK_FLAG_SYNCHRONIZING,
3373                             "SYNCHRONIZING");
3374                         ADD_FLAG(G_MIRROR_DISK_FLAG_FORCE_SYNC, "FORCE_SYNC");
3375                         ADD_FLAG(G_MIRROR_DISK_FLAG_BROKEN, "BROKEN");
3376 #undef  ADD_FLAG
3377                 }
3378                 sbuf_printf(sb, "</Flags>\n");
3379                 sbuf_printf(sb, "%s<Priority>%u</Priority>\n", indent,
3380                     disk->d_priority);
3381                 sbuf_printf(sb, "%s<State>%s</State>\n", indent,
3382                     g_mirror_disk_state2str(disk->d_state));
3383                 sx_xunlock(&sc->sc_lock);
3384                 g_topology_lock();
3385         } else {
3386                 g_topology_unlock();
3387                 sx_xlock(&sc->sc_lock);
3388                 sbuf_printf(sb, "%s<Type>", indent);
3389                 switch (sc->sc_type) {
3390                 case G_MIRROR_TYPE_AUTOMATIC:
3391                         sbuf_printf(sb, "AUTOMATIC");
3392                         break;
3393                 case G_MIRROR_TYPE_MANUAL:
3394                         sbuf_printf(sb, "MANUAL");
3395                         break;
3396                 default:
3397                         sbuf_printf(sb, "UNKNOWN");
3398                         break;
3399                 }
3400                 sbuf_printf(sb, "</Type>\n");
3401                 sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)sc->sc_id);
3402                 sbuf_printf(sb, "%s<SyncID>%u</SyncID>\n", indent, sc->sc_syncid);
3403                 sbuf_printf(sb, "%s<GenID>%u</GenID>\n", indent, sc->sc_genid);
3404                 sbuf_printf(sb, "%s<Flags>", indent);
3405                 if (sc->sc_flags == 0)
3406                         sbuf_printf(sb, "NONE");
3407                 else {
3408                         int first = 1;
3409
3410 #define ADD_FLAG(flag, name)    do {                                    \
3411         if ((sc->sc_flags & (flag)) != 0) {                             \
3412                 if (!first)                                             \
3413                         sbuf_printf(sb, ", ");                          \
3414                 else                                                    \
3415                         first = 0;                                      \
3416                 sbuf_printf(sb, name);                                  \
3417         }                                                               \
3418 } while (0)
3419                         ADD_FLAG(G_MIRROR_DEVICE_FLAG_NOFAILSYNC, "NOFAILSYNC");
3420                         ADD_FLAG(G_MIRROR_DEVICE_FLAG_NOAUTOSYNC, "NOAUTOSYNC");
3421 #undef  ADD_FLAG
3422                 }
3423                 sbuf_printf(sb, "</Flags>\n");
3424                 sbuf_printf(sb, "%s<Slice>%u</Slice>\n", indent,
3425                     (u_int)sc->sc_slice);
3426                 sbuf_printf(sb, "%s<Balance>%s</Balance>\n", indent,
3427                     balance_name(sc->sc_balance));
3428                 sbuf_printf(sb, "%s<Components>%u</Components>\n", indent,
3429                     sc->sc_ndisks);
3430                 sbuf_printf(sb, "%s<State>", indent);
3431                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING)
3432                         sbuf_printf(sb, "%s", "STARTING");
3433                 else if (sc->sc_ndisks ==
3434                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE))
3435                         sbuf_printf(sb, "%s", "COMPLETE");
3436                 else
3437                         sbuf_printf(sb, "%s", "DEGRADED");
3438                 sbuf_printf(sb, "</State>\n");
3439                 sx_xunlock(&sc->sc_lock);
3440                 g_topology_lock();
3441         }
3442 }
3443
3444 static void
3445 g_mirror_shutdown_post_sync(void *arg, int howto)
3446 {
3447         struct g_class *mp;
3448         struct g_geom *gp, *gp2;
3449         struct g_mirror_softc *sc;
3450         int error;
3451
3452         if (panicstr != NULL)
3453                 return;
3454
3455         mp = arg;
3456         g_topology_lock();
3457         g_mirror_shutdown = 1;
3458         LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
3459                 if ((sc = gp->softc) == NULL)
3460                         continue;
3461                 /* Skip synchronization geom. */
3462                 if (gp == sc->sc_sync.ds_geom)
3463                         continue;
3464                 g_topology_unlock();
3465                 sx_xlock(&sc->sc_lock);
3466                 g_mirror_idle(sc, -1);
3467                 g_cancel_event(sc);
3468                 error = g_mirror_destroy(sc, G_MIRROR_DESTROY_DELAYED);
3469                 if (error != 0)
3470                         sx_xunlock(&sc->sc_lock);
3471                 g_topology_lock();
3472         }
3473         g_topology_unlock();
3474 }
3475
3476 static void
3477 g_mirror_init(struct g_class *mp)
3478 {
3479
3480         g_mirror_post_sync = EVENTHANDLER_REGISTER(shutdown_post_sync,
3481             g_mirror_shutdown_post_sync, mp, SHUTDOWN_PRI_FIRST);
3482         if (g_mirror_post_sync == NULL)
3483                 G_MIRROR_DEBUG(0, "Warning! Cannot register shutdown event.");
3484 }
3485
3486 static void
3487 g_mirror_fini(struct g_class *mp)
3488 {
3489
3490         if (g_mirror_post_sync != NULL)
3491                 EVENTHANDLER_DEREGISTER(shutdown_post_sync, g_mirror_post_sync);
3492 }
3493
3494 DECLARE_GEOM_CLASS(g_mirror_class, g_mirror);