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/geom_dbg.h>
  51 #include <geom/mirror/g_mirror.h>
  52
  53 FEATURE(geom_mirror, "GEOM mirroring support");
  54
  55 static MALLOC_DEFINE(M_MIRROR, "mirror_data", "GEOM_MIRROR Data");
  56
  57 SYSCTL_DECL(_kern_geom);
  58 static SYSCTL_NODE(_kern_geom, OID_AUTO, mirror, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
  59     "GEOM_MIRROR stuff");
  60 int g_mirror_debug = 0;
  61 SYSCTL_INT(_kern_geom_mirror, OID_AUTO, debug, CTLFLAG_RWTUN, &g_mirror_debug, 0,
  62     "Debug level");
  63 bool g_launch_mirror_before_timeout = true;
  64 SYSCTL_BOOL(_kern_geom_mirror, OID_AUTO, launch_mirror_before_timeout,
  65     CTLFLAG_RWTUN, &g_launch_mirror_before_timeout, 0,
  66     "If false, force gmirror to wait out the full kern.geom.mirror.timeout "
  67     "before launching mirrors");
  68 static u_int g_mirror_timeout = 4;
  69 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, timeout, CTLFLAG_RWTUN, &g_mirror_timeout,
  70     0, "Time to wait on all mirror components");
  71 static u_int g_mirror_idletime = 5;
  72 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, idletime, CTLFLAG_RWTUN,
  73     &g_mirror_idletime, 0, "Mark components as clean when idling");
  74 static u_int g_mirror_disconnect_on_failure = 1;
  75 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, disconnect_on_failure, CTLFLAG_RWTUN,
  76     &g_mirror_disconnect_on_failure, 0, "Disconnect component on I/O failure.");
  77 static u_int g_mirror_syncreqs = 2;
  78 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, sync_requests, CTLFLAG_RDTUN,
  79     &g_mirror_syncreqs, 0, "Parallel synchronization I/O requests.");
  80 static u_int g_mirror_sync_period = 5;
  81 SYSCTL_UINT(_kern_geom_mirror, OID_AUTO, sync_update_period, CTLFLAG_RWTUN,
  82     &g_mirror_sync_period, 0,
  83     "Metadata update period during synchronization, in seconds");
  84
  85 #define MSLEEP(ident, mtx, priority, wmesg, timeout)    do {            \
  86         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, (ident));       \
  87         msleep((ident), (mtx), (priority), (wmesg), (timeout));         \
  88         G_MIRROR_DEBUG(4, "%s: Woken up %p.", __func__, (ident));       \
  89 } while (0)
  90
  91 static eventhandler_tag g_mirror_post_sync = NULL;
  92 static int g_mirror_shutdown = 0;
  93
  94 static g_ctl_destroy_geom_t g_mirror_destroy_geom;
  95 static g_taste_t g_mirror_taste;
  96 static g_init_t g_mirror_init;
  97 static g_fini_t g_mirror_fini;
  98 static g_provgone_t g_mirror_providergone;
  99 static g_resize_t g_mirror_resize;
 100
 101 struct g_class g_mirror_class = {
 102         .name = G_MIRROR_CLASS_NAME,
 103         .version = G_VERSION,
 104         .ctlreq = g_mirror_config,
 105         .taste = g_mirror_taste,
 106         .destroy_geom = g_mirror_destroy_geom,
 107         .init = g_mirror_init,
 108         .fini = g_mirror_fini,
 109         .providergone = g_mirror_providergone,
 110         .resize = g_mirror_resize
 111 };
 112
 113 static void g_mirror_destroy_provider(struct g_mirror_softc *sc);
 114 static int g_mirror_update_disk(struct g_mirror_disk *disk, u_int state);
 115 static void g_mirror_update_device(struct g_mirror_softc *sc, bool force);
 116 static void g_mirror_dumpconf(struct sbuf *sb, const char *indent,
 117     struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp);
 118 static void g_mirror_timeout_drain(struct g_mirror_softc *sc);
 119 static int g_mirror_refresh_device(struct g_mirror_softc *sc,
 120     const struct g_provider *pp, const struct g_mirror_metadata *md);
 121 static void g_mirror_sync_reinit(const struct g_mirror_disk *disk,
 122     struct bio *bp, off_t offset);
 123 static void g_mirror_sync_stop(struct g_mirror_disk *disk, int type);
 124 static void g_mirror_register_request(struct g_mirror_softc *sc,
 125     struct bio *bp);
 126 static void g_mirror_sync_release(struct g_mirror_softc *sc);
 127
 128 static const char *
 129 g_mirror_disk_state2str(int state)
 130 {
 131
 132         switch (state) {
 133         case G_MIRROR_DISK_STATE_NONE:
 134                 return ("NONE");
 135         case G_MIRROR_DISK_STATE_NEW:
 136                 return ("NEW");
 137         case G_MIRROR_DISK_STATE_ACTIVE:
 138                 return ("ACTIVE");
 139         case G_MIRROR_DISK_STATE_STALE:
 140                 return ("STALE");
 141         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
 142                 return ("SYNCHRONIZING");
 143         case G_MIRROR_DISK_STATE_DISCONNECTED:
 144                 return ("DISCONNECTED");
 145         case G_MIRROR_DISK_STATE_DESTROY:
 146                 return ("DESTROY");
 147         default:
 148                 return ("INVALID");
 149         }
 150 }
 151
 152 static const char *
 153 g_mirror_device_state2str(int state)
 154 {
 155
 156         switch (state) {
 157         case G_MIRROR_DEVICE_STATE_STARTING:
 158                 return ("STARTING");
 159         case G_MIRROR_DEVICE_STATE_RUNNING:
 160                 return ("RUNNING");
 161         default:
 162                 return ("INVALID");
 163         }
 164 }
 165
 166 static const char *
 167 g_mirror_get_diskname(struct g_mirror_disk *disk)
 168 {
 169
 170         if (disk->d_consumer == NULL || disk->d_consumer->provider == NULL)
 171                 return ("[unknown]");
 172         return (disk->d_name);
 173 }
 174
 175 /*
 176  * --- Events handling functions ---
 177  * Events in geom_mirror are used to maintain disks and device status
 178  * from one thread to simplify locking.
 179  */
 180 static void
 181 g_mirror_event_free(struct g_mirror_event *ep)
 182 {
 183
 184         free(ep, M_MIRROR);
 185 }
 186
 187 static int
 188 g_mirror_event_dispatch(struct g_mirror_event *ep, void *arg, int state,
 189     int flags)
 190 {
 191         struct g_mirror_softc *sc;
 192         struct g_mirror_disk *disk;
 193         int error;
 194
 195         G_MIRROR_DEBUG(4, "%s: Sending event %p.", __func__, ep);
 196         if ((flags & G_MIRROR_EVENT_DEVICE) != 0) {
 197                 disk = NULL;
 198                 sc = arg;
 199         } else {
 200                 disk = arg;
 201                 sc = disk->d_softc;
 202         }
 203         ep->e_disk = disk;
 204         ep->e_state = state;
 205         ep->e_flags = flags;
 206         ep->e_error = 0;
 207         mtx_lock(&sc->sc_events_mtx);
 208         TAILQ_INSERT_TAIL(&sc->sc_events, ep, e_next);
 209         mtx_unlock(&sc->sc_events_mtx);
 210         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
 211         mtx_lock(&sc->sc_queue_mtx);
 212         wakeup(sc);
 213         mtx_unlock(&sc->sc_queue_mtx);
 214         if ((flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 215                 return (0);
 216         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, ep);
 217         sx_xunlock(&sc->sc_lock);
 218         while ((ep->e_flags & G_MIRROR_EVENT_DONE) == 0) {
 219                 mtx_lock(&sc->sc_events_mtx);
 220                 MSLEEP(ep, &sc->sc_events_mtx, PRIBIO | PDROP, "m:event",
 221                     hz * 5);
 222         }
 223         error = ep->e_error;
 224         g_mirror_event_free(ep);
 225         sx_xlock(&sc->sc_lock);
 226         return (error);
 227 }
 228
 229 int
 230 g_mirror_event_send(void *arg, int state, int flags)
 231 {
 232         struct g_mirror_event *ep;
 233
 234         ep = malloc(sizeof(*ep), M_MIRROR, M_WAITOK);
 235         return (g_mirror_event_dispatch(ep, arg, state, flags));
 236 }
 237
 238 static struct g_mirror_event *
 239 g_mirror_event_first(struct g_mirror_softc *sc)
 240 {
 241         struct g_mirror_event *ep;
 242
 243         mtx_lock(&sc->sc_events_mtx);
 244         ep = TAILQ_FIRST(&sc->sc_events);
 245         mtx_unlock(&sc->sc_events_mtx);
 246         return (ep);
 247 }
 248
 249 static void
 250 g_mirror_event_remove(struct g_mirror_softc *sc, struct g_mirror_event *ep)
 251 {
 252
 253         mtx_lock(&sc->sc_events_mtx);
 254         TAILQ_REMOVE(&sc->sc_events, ep, e_next);
 255         mtx_unlock(&sc->sc_events_mtx);
 256 }
 257
 258 static void
 259 g_mirror_event_cancel(struct g_mirror_disk *disk)
 260 {
 261         struct g_mirror_softc *sc;
 262         struct g_mirror_event *ep, *tmpep;
 263
 264         sc = disk->d_softc;
 265         sx_assert(&sc->sc_lock, SX_XLOCKED);
 266
 267         mtx_lock(&sc->sc_events_mtx);
 268         TAILQ_FOREACH_SAFE(ep, &sc->sc_events, e_next, tmpep) {
 269                 if ((ep->e_flags & G_MIRROR_EVENT_DEVICE) != 0)
 270                         continue;
 271                 if (ep->e_disk != disk)
 272                         continue;
 273                 TAILQ_REMOVE(&sc->sc_events, ep, e_next);
 274                 if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 275                         g_mirror_event_free(ep);
 276                 else {
 277                         ep->e_error = ECANCELED;
 278                         wakeup(ep);
 279                 }
 280         }
 281         mtx_unlock(&sc->sc_events_mtx);
 282 }
 283
 284 /*
 285  * Return the number of disks in given state.
 286  * If state is equal to -1, count all connected disks.
 287  */
 288 u_int
 289 g_mirror_ndisks(struct g_mirror_softc *sc, int state)
 290 {
 291         struct g_mirror_disk *disk;
 292         u_int n = 0;
 293
 294         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 295                 if (state == -1 || disk->d_state == state)
 296                         n++;
 297         }
 298         return (n);
 299 }
 300
 301 /*
 302  * Find a disk in mirror by its disk ID.
 303  */
 304 static struct g_mirror_disk *
 305 g_mirror_id2disk(struct g_mirror_softc *sc, uint32_t id)
 306 {
 307         struct g_mirror_disk *disk;
 308
 309         sx_assert(&sc->sc_lock, SX_XLOCKED);
 310
 311         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 312                 if (disk->d_id == id)
 313                         return (disk);
 314         }
 315         return (NULL);
 316 }
 317
 318 static u_int
 319 g_mirror_nrequests(struct g_mirror_softc *sc, struct g_consumer *cp)
 320 {
 321         struct bio *bp;
 322         u_int nreqs = 0;
 323
 324         mtx_lock(&sc->sc_queue_mtx);
 325         TAILQ_FOREACH(bp, &sc->sc_queue, bio_queue) {
 326                 if (bp->bio_from == cp)
 327                         nreqs++;
 328         }
 329         mtx_unlock(&sc->sc_queue_mtx);
 330         return (nreqs);
 331 }
 332
 333 static int
 334 g_mirror_is_busy(struct g_mirror_softc *sc, struct g_consumer *cp)
 335 {
 336
 337         if (cp->index > 0) {
 338                 G_MIRROR_DEBUG(2,
 339                     "I/O requests for %s exist, can't destroy it now.",
 340                     cp->provider->name);
 341                 return (1);
 342         }
 343         if (g_mirror_nrequests(sc, cp) > 0) {
 344                 G_MIRROR_DEBUG(2,
 345                     "I/O requests for %s in queue, can't destroy it now.",
 346                     cp->provider->name);
 347                 return (1);
 348         }
 349         return (0);
 350 }
 351
 352 static void
 353 g_mirror_destroy_consumer(void *arg, int flags __unused)
 354 {
 355         struct g_consumer *cp;
 356
 357         g_topology_assert();
 358
 359         cp = arg;
 360         G_MIRROR_DEBUG(1, "Consumer %s destroyed.", cp->provider->name);
 361         g_detach(cp);
 362         g_destroy_consumer(cp);
 363 }
 364
 365 static void
 366 g_mirror_kill_consumer(struct g_mirror_softc *sc, struct g_consumer *cp)
 367 {
 368         struct g_provider *pp;
 369         int retaste_wait;
 370
 371         g_topology_assert();
 372
 373         cp->private = NULL;
 374         if (g_mirror_is_busy(sc, cp))
 375                 return;
 376         pp = cp->provider;
 377         retaste_wait = 0;
 378         if (cp->acw == 1) {
 379                 if ((pp->geom->flags & G_GEOM_WITHER) == 0)
 380                         retaste_wait = 1;
 381         }
 382         G_MIRROR_DEBUG(2, "Access %s r%dw%de%d = %d", pp->name, -cp->acr,
 383             -cp->acw, -cp->ace, 0);
 384         if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
 385                 g_access(cp, -cp->acr, -cp->acw, -cp->ace);
 386         if (retaste_wait) {
 387                 /*
 388                  * After retaste event was send (inside g_access()), we can send
 389                  * event to detach and destroy consumer.
 390                  * A class, which has consumer to the given provider connected
 391                  * will not receive retaste event for the provider.
 392                  * This is the way how I ignore retaste events when I close
 393                  * consumers opened for write: I detach and destroy consumer
 394                  * after retaste event is sent.
 395                  */
 396                 g_post_event(g_mirror_destroy_consumer, cp, M_WAITOK, NULL);
 397                 return;
 398         }
 399         G_MIRROR_DEBUG(1, "Consumer %s destroyed.", pp->name);
 400         g_detach(cp);
 401         g_destroy_consumer(cp);
 402 }
 403
 404 static int
 405 g_mirror_connect_disk(struct g_mirror_disk *disk, struct g_provider *pp)
 406 {
 407         struct g_consumer *cp;
 408         int error;
 409
 410         g_topology_assert_not();
 411         KASSERT(disk->d_consumer == NULL,
 412             ("Disk already connected (device %s).", disk->d_softc->sc_name));
 413
 414         g_topology_lock();
 415         cp = g_new_consumer(disk->d_softc->sc_geom);
 416         cp->flags |= G_CF_DIRECT_RECEIVE;
 417         error = g_attach(cp, pp);
 418         if (error != 0) {
 419                 g_destroy_consumer(cp);
 420                 g_topology_unlock();
 421                 return (error);
 422         }
 423         error = g_access(cp, 1, 1, 1);
 424         if (error != 0) {
 425                 g_detach(cp);
 426                 g_destroy_consumer(cp);
 427                 g_topology_unlock();
 428                 G_MIRROR_DEBUG(0, "Cannot open consumer %s (error=%d).",
 429                     pp->name, error);
 430                 return (error);
 431         }
 432         g_topology_unlock();
 433         disk->d_consumer = cp;
 434         disk->d_consumer->private = disk;
 435         disk->d_consumer->index = 0;
 436
 437         G_MIRROR_DEBUG(2, "Disk %s connected.", g_mirror_get_diskname(disk));
 438         return (0);
 439 }
 440
 441 static void
 442 g_mirror_disconnect_consumer(struct g_mirror_softc *sc, struct g_consumer *cp)
 443 {
 444
 445         g_topology_assert();
 446
 447         if (cp == NULL)
 448                 return;
 449         if (cp->provider != NULL)
 450                 g_mirror_kill_consumer(sc, cp);
 451         else
 452                 g_destroy_consumer(cp);
 453 }
 454
 455 /*
 456  * Initialize disk. This means allocate memory, create consumer, attach it
 457  * to the provider and open access (r1w1e1) to it.
 458  */
 459 static struct g_mirror_disk *
 460 g_mirror_init_disk(struct g_mirror_softc *sc, struct g_provider *pp,
 461     struct g_mirror_metadata *md, int *errorp)
 462 {
 463         struct g_mirror_disk *disk;
 464         int i, error;
 465
 466         disk = malloc(sizeof(*disk), M_MIRROR, M_NOWAIT | M_ZERO);
 467         if (disk == NULL) {
 468                 error = ENOMEM;
 469                 goto fail;
 470         }
 471         disk->d_softc = sc;
 472         error = g_mirror_connect_disk(disk, pp);
 473         if (error != 0)
 474                 goto fail;
 475         disk->d_id = md->md_did;
 476         disk->d_state = G_MIRROR_DISK_STATE_NONE;
 477         disk->d_priority = md->md_priority;
 478         disk->d_flags = md->md_dflags;
 479         error = g_getattr("GEOM::candelete", disk->d_consumer, &i);
 480         if (error == 0 && i != 0)
 481                 disk->d_flags |= G_MIRROR_DISK_FLAG_CANDELETE;
 482         if (md->md_provider[0] != '\0')
 483                 disk->d_flags |= G_MIRROR_DISK_FLAG_HARDCODED;
 484         disk->d_sync.ds_consumer = NULL;
 485         disk->d_sync.ds_offset = md->md_sync_offset;
 486         disk->d_sync.ds_offset_done = md->md_sync_offset;
 487         disk->d_sync.ds_update_ts = time_uptime;
 488         disk->d_genid = md->md_genid;
 489         disk->d_sync.ds_syncid = md->md_syncid;
 490         disk->d_init_ndisks = md->md_all;
 491         disk->d_init_slice = md->md_slice;
 492         disk->d_init_balance = md->md_balance;
 493         disk->d_init_mediasize = md->md_mediasize;
 494         if (errorp != NULL)
 495                 *errorp = 0;
 496         return (disk);
 497 fail:
 498         if (errorp != NULL)
 499                 *errorp = error;
 500         if (disk != NULL)
 501                 free(disk, M_MIRROR);
 502         return (NULL);
 503 }
 504
 505 static void
 506 g_mirror_destroy_disk(struct g_mirror_disk *disk)
 507 {
 508         struct g_mirror_softc *sc;
 509
 510         g_topology_assert_not();
 511         sc = disk->d_softc;
 512         sx_assert(&sc->sc_lock, SX_XLOCKED);
 513
 514         g_topology_lock();
 515         LIST_REMOVE(disk, d_next);
 516         g_topology_unlock();
 517         g_mirror_event_cancel(disk);
 518         if (sc->sc_hint == disk)
 519                 sc->sc_hint = NULL;
 520         switch (disk->d_state) {
 521         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
 522                 g_mirror_sync_stop(disk, 1);
 523                 /* FALLTHROUGH */
 524         case G_MIRROR_DISK_STATE_NEW:
 525         case G_MIRROR_DISK_STATE_STALE:
 526         case G_MIRROR_DISK_STATE_ACTIVE:
 527                 g_topology_lock();
 528                 g_mirror_disconnect_consumer(sc, disk->d_consumer);
 529                 g_topology_unlock();
 530                 free(disk, M_MIRROR);
 531                 break;
 532         default:
 533                 KASSERT(0 == 1, ("Wrong disk state (%s, %s).",
 534                     g_mirror_get_diskname(disk),
 535                     g_mirror_disk_state2str(disk->d_state)));
 536         }
 537 }
 538
 539 static void
 540 g_mirror_free_device(struct g_mirror_softc *sc)
 541 {
 542
 543         g_topology_assert();
 544
 545         mtx_destroy(&sc->sc_queue_mtx);
 546         mtx_destroy(&sc->sc_events_mtx);
 547         mtx_destroy(&sc->sc_done_mtx);
 548         sx_destroy(&sc->sc_lock);
 549         free(sc, M_MIRROR);
 550 }
 551
 552 static void
 553 g_mirror_providergone(struct g_provider *pp)
 554 {
 555         struct g_mirror_softc *sc = pp->private;
 556
 557         if ((--sc->sc_refcnt) == 0)
 558                 g_mirror_free_device(sc);
 559 }
 560
 561 static void
 562 g_mirror_destroy_device(struct g_mirror_softc *sc)
 563 {
 564         struct g_mirror_disk *disk;
 565         struct g_mirror_event *ep;
 566         struct g_geom *gp;
 567         struct g_consumer *cp, *tmpcp;
 568
 569         g_topology_assert_not();
 570         sx_assert(&sc->sc_lock, SX_XLOCKED);
 571
 572         gp = sc->sc_geom;
 573         if (sc->sc_provider != NULL)
 574                 g_mirror_destroy_provider(sc);
 575         for (disk = LIST_FIRST(&sc->sc_disks); disk != NULL;
 576             disk = LIST_FIRST(&sc->sc_disks)) {
 577                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
 578                 g_mirror_update_metadata(disk);
 579                 g_mirror_destroy_disk(disk);
 580         }
 581         while ((ep = g_mirror_event_first(sc)) != NULL) {
 582                 g_mirror_event_remove(sc, ep);
 583                 if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0)
 584                         g_mirror_event_free(ep);
 585                 else {
 586                         ep->e_error = ECANCELED;
 587                         ep->e_flags |= G_MIRROR_EVENT_DONE;
 588                         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, ep);
 589                         mtx_lock(&sc->sc_events_mtx);
 590                         wakeup(ep);
 591                         mtx_unlock(&sc->sc_events_mtx);
 592                 }
 593         }
 594         g_mirror_timeout_drain(sc);
 595
 596         g_topology_lock();
 597         LIST_FOREACH_SAFE(cp, &sc->sc_sync.ds_geom->consumer, consumer, tmpcp) {
 598                 g_mirror_disconnect_consumer(sc, cp);
 599         }
 600         g_wither_geom(sc->sc_sync.ds_geom, ENXIO);
 601         G_MIRROR_DEBUG(0, "Device %s destroyed.", gp->name);
 602         g_wither_geom(gp, ENXIO);
 603         sx_xunlock(&sc->sc_lock);
 604         if ((--sc->sc_refcnt) == 0)
 605                 g_mirror_free_device(sc);
 606         g_topology_unlock();
 607 }
 608
 609 static void
 610 g_mirror_orphan(struct g_consumer *cp)
 611 {
 612         struct g_mirror_disk *disk;
 613
 614         g_topology_assert();
 615
 616         disk = cp->private;
 617         if (disk == NULL)
 618                 return;
 619         disk->d_softc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
 620         g_mirror_event_send(disk, G_MIRROR_DISK_STATE_DISCONNECTED,
 621             G_MIRROR_EVENT_DONTWAIT);
 622 }
 623
 624 /*
 625  * Function should return the next active disk on the list.
 626  * It is possible that it will be the same disk as given.
 627  * If there are no active disks on list, NULL is returned.
 628  */
 629 static __inline struct g_mirror_disk *
 630 g_mirror_find_next(struct g_mirror_softc *sc, struct g_mirror_disk *disk)
 631 {
 632         struct g_mirror_disk *dp;
 633
 634         for (dp = LIST_NEXT(disk, d_next); dp != disk;
 635             dp = LIST_NEXT(dp, d_next)) {
 636                 if (dp == NULL)
 637                         dp = LIST_FIRST(&sc->sc_disks);
 638                 if (dp->d_state == G_MIRROR_DISK_STATE_ACTIVE)
 639                         break;
 640         }
 641         if (dp->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 642                 return (NULL);
 643         return (dp);
 644 }
 645
 646 static struct g_mirror_disk *
 647 g_mirror_get_disk(struct g_mirror_softc *sc)
 648 {
 649         struct g_mirror_disk *disk;
 650
 651         if (sc->sc_hint == NULL) {
 652                 sc->sc_hint = LIST_FIRST(&sc->sc_disks);
 653                 if (sc->sc_hint == NULL)
 654                         return (NULL);
 655         }
 656         disk = sc->sc_hint;
 657         if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE) {
 658                 disk = g_mirror_find_next(sc, disk);
 659                 if (disk == NULL)
 660                         return (NULL);
 661         }
 662         sc->sc_hint = g_mirror_find_next(sc, disk);
 663         return (disk);
 664 }
 665
 666 static int
 667 g_mirror_write_metadata(struct g_mirror_disk *disk,
 668     struct g_mirror_metadata *md)
 669 {
 670         struct g_mirror_softc *sc;
 671         struct g_consumer *cp;
 672         off_t offset, length;
 673         u_char *sector;
 674         int error = 0;
 675
 676         g_topology_assert_not();
 677         sc = disk->d_softc;
 678         sx_assert(&sc->sc_lock, SX_LOCKED);
 679
 680         cp = disk->d_consumer;
 681         KASSERT(cp != NULL, ("NULL consumer (%s).", sc->sc_name));
 682         KASSERT(cp->provider != NULL, ("NULL provider (%s).", sc->sc_name));
 683         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
 684             ("Consumer %s closed? (r%dw%de%d).", cp->provider->name, cp->acr,
 685             cp->acw, cp->ace));
 686         length = cp->provider->sectorsize;
 687         offset = cp->provider->mediasize - length;
 688         sector = malloc((size_t)length, M_MIRROR, M_WAITOK | M_ZERO);
 689         if (md != NULL &&
 690             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_WIPE) == 0) {
 691                 /*
 692                  * Handle the case, when the size of parent provider reduced.
 693                  */
 694                 if (offset < md->md_mediasize)
 695                         error = ENOSPC;
 696                 else
 697                         mirror_metadata_encode(md, sector);
 698         }
 699         KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_metadata_write, error);
 700         if (error == 0)
 701                 error = g_write_data(cp, offset, sector, length);
 702         free(sector, M_MIRROR);
 703         if (error != 0) {
 704                 if ((disk->d_flags & G_MIRROR_DISK_FLAG_BROKEN) == 0) {
 705                         disk->d_flags |= G_MIRROR_DISK_FLAG_BROKEN;
 706                         G_MIRROR_DEBUG(0, "Cannot write metadata on %s "
 707                             "(device=%s, error=%d).",
 708                             g_mirror_get_diskname(disk), sc->sc_name, error);
 709                 } else {
 710                         G_MIRROR_DEBUG(1, "Cannot write metadata on %s "
 711                             "(device=%s, error=%d).",
 712                             g_mirror_get_diskname(disk), sc->sc_name, error);
 713                 }
 714                 if (g_mirror_disconnect_on_failure &&
 715                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 1) {
 716                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
 717                         g_mirror_event_send(disk,
 718                             G_MIRROR_DISK_STATE_DISCONNECTED,
 719                             G_MIRROR_EVENT_DONTWAIT);
 720                 }
 721         }
 722         return (error);
 723 }
 724
 725 static int
 726 g_mirror_clear_metadata(struct g_mirror_disk *disk)
 727 {
 728         int error;
 729
 730         g_topology_assert_not();
 731         sx_assert(&disk->d_softc->sc_lock, SX_LOCKED);
 732
 733         if (disk->d_softc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
 734                 return (0);
 735         error = g_mirror_write_metadata(disk, NULL);
 736         if (error == 0) {
 737                 G_MIRROR_DEBUG(2, "Metadata on %s cleared.",
 738                     g_mirror_get_diskname(disk));
 739         } else {
 740                 G_MIRROR_DEBUG(0,
 741                     "Cannot clear metadata on disk %s (error=%d).",
 742                     g_mirror_get_diskname(disk), error);
 743         }
 744         return (error);
 745 }
 746
 747 void
 748 g_mirror_fill_metadata(struct g_mirror_softc *sc, struct g_mirror_disk *disk,
 749     struct g_mirror_metadata *md)
 750 {
 751
 752         bzero(md, sizeof(*md));
 753         strlcpy(md->md_magic, G_MIRROR_MAGIC, sizeof(md->md_magic));
 754         md->md_version = G_MIRROR_VERSION;
 755         strlcpy(md->md_name, sc->sc_name, sizeof(md->md_name));
 756         md->md_mid = sc->sc_id;
 757         md->md_all = sc->sc_ndisks;
 758         md->md_slice = sc->sc_slice;
 759         md->md_balance = sc->sc_balance;
 760         md->md_genid = sc->sc_genid;
 761         md->md_mediasize = sc->sc_mediasize;
 762         md->md_sectorsize = sc->sc_sectorsize;
 763         md->md_mflags = (sc->sc_flags & G_MIRROR_DEVICE_FLAG_MASK);
 764         if (disk == NULL) {
 765                 md->md_did = arc4random();
 766         } else {
 767                 md->md_did = disk->d_id;
 768                 md->md_priority = disk->d_priority;
 769                 md->md_syncid = disk->d_sync.ds_syncid;
 770                 md->md_dflags = (disk->d_flags & G_MIRROR_DISK_FLAG_MASK);
 771                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
 772                         md->md_sync_offset = disk->d_sync.ds_offset_done;
 773                 if ((disk->d_flags & G_MIRROR_DISK_FLAG_HARDCODED) != 0) {
 774                         strlcpy(md->md_provider,
 775                             disk->d_consumer->provider->name,
 776                             sizeof(md->md_provider));
 777                 }
 778                 md->md_provsize = disk->d_consumer->provider->mediasize;
 779         }
 780 }
 781
 782 void
 783 g_mirror_update_metadata(struct g_mirror_disk *disk)
 784 {
 785         struct g_mirror_softc *sc;
 786         struct g_mirror_metadata md;
 787         int error;
 788
 789         g_topology_assert_not();
 790         sc = disk->d_softc;
 791         sx_assert(&sc->sc_lock, SX_LOCKED);
 792
 793         if (sc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
 794                 return;
 795         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_WIPE) == 0)
 796                 g_mirror_fill_metadata(sc, disk, &md);
 797         error = g_mirror_write_metadata(disk, &md);
 798         if (error == 0) {
 799                 G_MIRROR_DEBUG(2, "Metadata on %s updated.",
 800                     g_mirror_get_diskname(disk));
 801         } else {
 802                 G_MIRROR_DEBUG(0,
 803                     "Cannot update metadata on disk %s (error=%d).",
 804                     g_mirror_get_diskname(disk), error);
 805         }
 806 }
 807
 808 static void
 809 g_mirror_bump_syncid(struct g_mirror_softc *sc)
 810 {
 811         struct g_mirror_disk *disk;
 812
 813         g_topology_assert_not();
 814         sx_assert(&sc->sc_lock, SX_XLOCKED);
 815         KASSERT(g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 0,
 816             ("%s called with no active disks (device=%s).", __func__,
 817             sc->sc_name));
 818
 819         sc->sc_syncid++;
 820         G_MIRROR_DEBUG(1, "Device %s: syncid bumped to %u.", sc->sc_name,
 821             sc->sc_syncid);
 822         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 823                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
 824                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
 825                         disk->d_sync.ds_syncid = sc->sc_syncid;
 826                         g_mirror_update_metadata(disk);
 827                 }
 828         }
 829 }
 830
 831 static void
 832 g_mirror_bump_genid(struct g_mirror_softc *sc)
 833 {
 834         struct g_mirror_disk *disk;
 835
 836         g_topology_assert_not();
 837         sx_assert(&sc->sc_lock, SX_XLOCKED);
 838         KASSERT(g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 0,
 839             ("%s called with no active disks (device=%s).", __func__,
 840             sc->sc_name));
 841
 842         sc->sc_genid++;
 843         G_MIRROR_DEBUG(1, "Device %s: genid bumped to %u.", sc->sc_name,
 844             sc->sc_genid);
 845         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 846                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
 847                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
 848                         disk->d_genid = sc->sc_genid;
 849                         g_mirror_update_metadata(disk);
 850                 }
 851         }
 852 }
 853
 854 static int
 855 g_mirror_idle(struct g_mirror_softc *sc, int acw)
 856 {
 857         struct g_mirror_disk *disk;
 858         int timeout;
 859
 860         g_topology_assert_not();
 861         sx_assert(&sc->sc_lock, SX_XLOCKED);
 862
 863         if (sc->sc_provider == NULL)
 864                 return (0);
 865         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
 866                 return (0);
 867         if (sc->sc_idle)
 868                 return (0);
 869         if (sc->sc_writes > 0)
 870                 return (0);
 871         if (acw > 0 || (acw == -1 && sc->sc_provider->acw > 0)) {
 872                 timeout = g_mirror_idletime - (time_uptime - sc->sc_last_write);
 873                 if (!g_mirror_shutdown && timeout > 0)
 874                         return (timeout);
 875         }
 876         sc->sc_idle = 1;
 877         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 878                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 879                         continue;
 880                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as clean.",
 881                     g_mirror_get_diskname(disk), sc->sc_name);
 882                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
 883                 g_mirror_update_metadata(disk);
 884         }
 885         return (0);
 886 }
 887
 888 static void
 889 g_mirror_unidle(struct g_mirror_softc *sc)
 890 {
 891         struct g_mirror_disk *disk;
 892
 893         g_topology_assert_not();
 894         sx_assert(&sc->sc_lock, SX_XLOCKED);
 895
 896         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
 897                 return;
 898         sc->sc_idle = 0;
 899         sc->sc_last_write = time_uptime;
 900         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
 901                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
 902                         continue;
 903                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as dirty.",
 904                     g_mirror_get_diskname(disk), sc->sc_name);
 905                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
 906                 g_mirror_update_metadata(disk);
 907         }
 908 }
 909
 910 static void
 911 g_mirror_done(struct bio *bp)
 912 {
 913         struct g_mirror_softc *sc;
 914
 915         sc = bp->bio_from->geom->softc;
 916         bp->bio_cflags = G_MIRROR_BIO_FLAG_REGULAR;
 917         mtx_lock(&sc->sc_queue_mtx);
 918         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
 919         mtx_unlock(&sc->sc_queue_mtx);
 920         wakeup(sc);
 921 }
 922
 923 static void
 924 g_mirror_regular_request_error(struct g_mirror_softc *sc,
 925     struct g_mirror_disk *disk, struct bio *bp)
 926 {
 927
 928         if ((bp->bio_cmd == BIO_FLUSH || bp->bio_cmd == BIO_SPEEDUP) &&
 929             bp->bio_error == EOPNOTSUPP)
 930                 return;
 931
 932         if ((disk->d_flags & G_MIRROR_DISK_FLAG_BROKEN) == 0) {
 933                 disk->d_flags |= G_MIRROR_DISK_FLAG_BROKEN;
 934                 G_MIRROR_LOGREQ(0, bp, "Request failed (error=%d).",
 935                     bp->bio_error);
 936         } else {
 937                 G_MIRROR_LOGREQ(1, bp, "Request failed (error=%d).",
 938                     bp->bio_error);
 939         }
 940         if (g_mirror_disconnect_on_failure &&
 941             g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) > 1) {
 942                 if (bp->bio_error == ENXIO &&
 943                     bp->bio_cmd == BIO_READ)
 944                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
 945                 else if (bp->bio_error == ENXIO)
 946                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID_NOW;
 947                 else
 948                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
 949                 g_mirror_event_send(disk, G_MIRROR_DISK_STATE_DISCONNECTED,
 950                     G_MIRROR_EVENT_DONTWAIT);
 951         }
 952 }
 953
 954 static void
 955 g_mirror_regular_request(struct g_mirror_softc *sc, struct bio *bp)
 956 {
 957         struct g_mirror_disk *disk;
 958         struct bio *pbp;
 959
 960         g_topology_assert_not();
 961         KASSERT(sc->sc_provider == bp->bio_parent->bio_to,
 962             ("regular request %p with unexpected origin", bp));
 963
 964         pbp = bp->bio_parent;
 965         bp->bio_from->index--;
 966         if (bp->bio_cmd == BIO_WRITE || bp->bio_cmd == BIO_DELETE)
 967                 sc->sc_writes--;
 968         disk = bp->bio_from->private;
 969         if (disk == NULL) {
 970                 g_topology_lock();
 971                 g_mirror_kill_consumer(sc, bp->bio_from);
 972                 g_topology_unlock();
 973         }
 974
 975         switch (bp->bio_cmd) {
 976         case BIO_READ:
 977                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_read,
 978                     bp->bio_error);
 979                 break;
 980         case BIO_WRITE:
 981                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_write,
 982                     bp->bio_error);
 983                 break;
 984         case BIO_DELETE:
 985                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_delete,
 986                     bp->bio_error);
 987                 break;
 988         case BIO_FLUSH:
 989                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_flush,
 990                     bp->bio_error);
 991                 break;
 992         case BIO_SPEEDUP:
 993                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_regular_request_speedup,
 994                     bp->bio_error);
 995                 break;
 996         }
 997
 998         pbp->bio_inbed++;
 999         KASSERT(pbp->bio_inbed <= pbp->bio_children,
1000             ("bio_inbed (%u) is bigger than bio_children (%u).", pbp->bio_inbed,
1001             pbp->bio_children));
1002         if (bp->bio_error == 0 && pbp->bio_error == 0) {
1003                 G_MIRROR_LOGREQ(3, bp, "Request delivered.");
1004                 g_destroy_bio(bp);
1005                 if (pbp->bio_children == pbp->bio_inbed) {
1006                         G_MIRROR_LOGREQ(3, pbp, "Request delivered.");
1007                         pbp->bio_completed = pbp->bio_length;
1008                         if (pbp->bio_cmd == BIO_WRITE ||
1009                             pbp->bio_cmd == BIO_DELETE) {
1010                                 TAILQ_REMOVE(&sc->sc_inflight, pbp, bio_queue);
1011                                 /* Release delayed sync requests if possible. */
1012                                 g_mirror_sync_release(sc);
1013                         }
1014                         g_io_deliver(pbp, pbp->bio_error);
1015                 }
1016                 return;
1017         } else if (bp->bio_error != 0) {
1018                 if (pbp->bio_error == 0)
1019                         pbp->bio_error = bp->bio_error;
1020                 if (disk != NULL)
1021                         g_mirror_regular_request_error(sc, disk, bp);
1022                 switch (pbp->bio_cmd) {
1023                 case BIO_DELETE:
1024                 case BIO_WRITE:
1025                 case BIO_FLUSH:
1026                 case BIO_SPEEDUP:
1027                         pbp->bio_inbed--;
1028                         pbp->bio_children--;
1029                         break;
1030                 }
1031         }
1032         g_destroy_bio(bp);
1033
1034         switch (pbp->bio_cmd) {
1035         case BIO_READ:
1036                 if (pbp->bio_inbed < pbp->bio_children)
1037                         break;
1038
1039                 /*
1040                  * If there is only one active disk we want to double-check that
1041                  * it is, in fact, the disk that we already tried.  This is
1042                  * necessary because we might have just lost a race with a
1043                  * removal of the tried disk (likely because of the same error)
1044                  * and the only remaining disk is still viable for a retry.
1045                  */
1046                 if (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 1 &&
1047                     disk != NULL &&
1048                     disk->d_state == G_MIRROR_DISK_STATE_ACTIVE) {
1049                         g_io_deliver(pbp, pbp->bio_error);
1050                 } else {
1051                         pbp->bio_error = 0;
1052                         mtx_lock(&sc->sc_queue_mtx);
1053                         TAILQ_INSERT_TAIL(&sc->sc_queue, pbp, bio_queue);
1054                         mtx_unlock(&sc->sc_queue_mtx);
1055                         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
1056                         wakeup(sc);
1057                 }
1058                 break;
1059         case BIO_DELETE:
1060         case BIO_WRITE:
1061         case BIO_FLUSH:
1062         case BIO_SPEEDUP:
1063                 if (pbp->bio_children == 0) {
1064                         /*
1065                          * All requests failed.
1066                          */
1067                 } else if (pbp->bio_inbed < pbp->bio_children) {
1068                         /* Do nothing. */
1069                         break;
1070                 } else if (pbp->bio_children == pbp->bio_inbed) {
1071                         /* Some requests succeeded. */
1072                         pbp->bio_error = 0;
1073                         pbp->bio_completed = pbp->bio_length;
1074                 }
1075                 if (pbp->bio_cmd == BIO_WRITE || pbp->bio_cmd == BIO_DELETE) {
1076                         TAILQ_REMOVE(&sc->sc_inflight, pbp, bio_queue);
1077                         /* Release delayed sync requests if possible. */
1078                         g_mirror_sync_release(sc);
1079                 }
1080                 g_io_deliver(pbp, pbp->bio_error);
1081                 break;
1082         default:
1083                 KASSERT(1 == 0, ("Invalid request: %u.", pbp->bio_cmd));
1084                 break;
1085         }
1086 }
1087
1088 static void
1089 g_mirror_sync_done(struct bio *bp)
1090 {
1091         struct g_mirror_softc *sc;
1092
1093         G_MIRROR_LOGREQ(3, bp, "Synchronization request delivered.");
1094         sc = bp->bio_from->geom->softc;
1095         bp->bio_cflags = G_MIRROR_BIO_FLAG_SYNC;
1096         mtx_lock(&sc->sc_queue_mtx);
1097         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
1098         mtx_unlock(&sc->sc_queue_mtx);
1099         wakeup(sc);
1100 }
1101
1102 static void
1103 g_mirror_candelete(struct bio *bp)
1104 {
1105         struct g_mirror_softc *sc;
1106         struct g_mirror_disk *disk;
1107         int val;
1108
1109         sc = bp->bio_to->private;
1110         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1111                 if (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE)
1112                         break;
1113         }
1114         val = disk != NULL;
1115         g_handleattr(bp, "GEOM::candelete", &val, sizeof(val));
1116 }
1117
1118 static void
1119 g_mirror_kernel_dump(struct bio *bp)
1120 {
1121         struct g_mirror_softc *sc;
1122         struct g_mirror_disk *disk;
1123         struct bio *cbp;
1124         struct g_kerneldump *gkd;
1125
1126         /*
1127          * We configure dumping to the first component, because this component
1128          * will be used for reading with 'prefer' balance algorithm.
1129          * If the component with the highest priority is currently disconnected
1130          * we will not be able to read the dump after the reboot if it will be
1131          * connected and synchronized later. Can we do something better?
1132          */
1133         sc = bp->bio_to->private;
1134         disk = LIST_FIRST(&sc->sc_disks);
1135
1136         gkd = (struct g_kerneldump *)bp->bio_data;
1137         if (gkd->length > bp->bio_to->mediasize)
1138                 gkd->length = bp->bio_to->mediasize;
1139         cbp = g_clone_bio(bp);
1140         if (cbp == NULL) {
1141                 g_io_deliver(bp, ENOMEM);
1142                 return;
1143         }
1144         cbp->bio_done = g_std_done;
1145         g_io_request(cbp, disk->d_consumer);
1146         G_MIRROR_DEBUG(1, "Kernel dump will go to %s.",
1147             g_mirror_get_diskname(disk));
1148 }
1149
1150 static void
1151 g_mirror_start(struct bio *bp)
1152 {
1153         struct g_mirror_softc *sc;
1154
1155         sc = bp->bio_to->private;
1156         /*
1157          * If sc == NULL or there are no valid disks, provider's error
1158          * should be set and g_mirror_start() should not be called at all.
1159          */
1160         KASSERT(sc != NULL && sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
1161             ("Provider's error should be set (error=%d)(mirror=%s).",
1162             bp->bio_to->error, bp->bio_to->name));
1163         G_MIRROR_LOGREQ(3, bp, "Request received.");
1164
1165         switch (bp->bio_cmd) {
1166         case BIO_READ:
1167         case BIO_WRITE:
1168         case BIO_DELETE:
1169         case BIO_SPEEDUP:
1170         case BIO_FLUSH:
1171                 break;
1172         case BIO_GETATTR:
1173                 if (!strcmp(bp->bio_attribute, "GEOM::candelete")) {
1174                         g_mirror_candelete(bp);
1175                         return;
1176                 } else if (strcmp("GEOM::kerneldump", bp->bio_attribute) == 0) {
1177                         g_mirror_kernel_dump(bp);
1178                         return;
1179                 }
1180                 /* FALLTHROUGH */
1181         default:
1182                 g_io_deliver(bp, EOPNOTSUPP);
1183                 return;
1184         }
1185         mtx_lock(&sc->sc_queue_mtx);
1186         if (bp->bio_to->error != 0) {
1187                 mtx_unlock(&sc->sc_queue_mtx);
1188                 g_io_deliver(bp, bp->bio_to->error);
1189                 return;
1190         }
1191         TAILQ_INSERT_TAIL(&sc->sc_queue, bp, bio_queue);
1192         mtx_unlock(&sc->sc_queue_mtx);
1193         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
1194         wakeup(sc);
1195 }
1196
1197 /*
1198  * Return TRUE if the given request is colliding with a in-progress
1199  * synchronization request.
1200  */
1201 static bool
1202 g_mirror_sync_collision(struct g_mirror_softc *sc, struct bio *bp)
1203 {
1204         struct g_mirror_disk *disk;
1205         struct bio *sbp;
1206         off_t rstart, rend, sstart, send;
1207         u_int i;
1208
1209         if (sc->sc_sync.ds_ndisks == 0)
1210                 return (false);
1211         rstart = bp->bio_offset;
1212         rend = bp->bio_offset + bp->bio_length;
1213         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1214                 if (disk->d_state != G_MIRROR_DISK_STATE_SYNCHRONIZING)
1215                         continue;
1216                 for (i = 0; i < g_mirror_syncreqs; i++) {
1217                         sbp = disk->d_sync.ds_bios[i];
1218                         if (sbp == NULL)
1219                                 continue;
1220                         sstart = sbp->bio_offset;
1221                         send = sbp->bio_offset + sbp->bio_length;
1222                         if (rend > sstart && rstart < send)
1223                                 return (true);
1224                 }
1225         }
1226         return (false);
1227 }
1228
1229 /*
1230  * Return TRUE if the given sync request is colliding with a in-progress regular
1231  * request.
1232  */
1233 static bool
1234 g_mirror_regular_collision(struct g_mirror_softc *sc, struct bio *sbp)
1235 {
1236         off_t rstart, rend, sstart, send;
1237         struct bio *bp;
1238
1239         if (sc->sc_sync.ds_ndisks == 0)
1240                 return (false);
1241         sstart = sbp->bio_offset;
1242         send = sbp->bio_offset + sbp->bio_length;
1243         TAILQ_FOREACH(bp, &sc->sc_inflight, bio_queue) {
1244                 rstart = bp->bio_offset;
1245                 rend = bp->bio_offset + bp->bio_length;
1246                 if (rend > sstart && rstart < send)
1247                         return (true);
1248         }
1249         return (false);
1250 }
1251
1252 /*
1253  * Puts regular request onto delayed queue.
1254  */
1255 static void
1256 g_mirror_regular_delay(struct g_mirror_softc *sc, struct bio *bp)
1257 {
1258
1259         G_MIRROR_LOGREQ(2, bp, "Delaying request.");
1260         TAILQ_INSERT_TAIL(&sc->sc_regular_delayed, bp, bio_queue);
1261 }
1262
1263 /*
1264  * Puts synchronization request onto delayed queue.
1265  */
1266 static void
1267 g_mirror_sync_delay(struct g_mirror_softc *sc, struct bio *bp)
1268 {
1269
1270         G_MIRROR_LOGREQ(2, bp, "Delaying synchronization request.");
1271         TAILQ_INSERT_TAIL(&sc->sc_sync_delayed, bp, bio_queue);
1272 }
1273
1274 /*
1275  * Requeue delayed regular requests.
1276  */
1277 static void
1278 g_mirror_regular_release(struct g_mirror_softc *sc)
1279 {
1280         struct bio *bp;
1281
1282         if ((bp = TAILQ_FIRST(&sc->sc_regular_delayed)) == NULL)
1283                 return;
1284         if (g_mirror_sync_collision(sc, bp))
1285                 return;
1286
1287         G_MIRROR_DEBUG(2, "Requeuing regular requests after collision.");
1288         mtx_lock(&sc->sc_queue_mtx);
1289         TAILQ_CONCAT(&sc->sc_regular_delayed, &sc->sc_queue, bio_queue);
1290         TAILQ_SWAP(&sc->sc_regular_delayed, &sc->sc_queue, bio, bio_queue);
1291         mtx_unlock(&sc->sc_queue_mtx);
1292 }
1293
1294 /*
1295  * Releases delayed sync requests which don't collide anymore with regular
1296  * requests.
1297  */
1298 static void
1299 g_mirror_sync_release(struct g_mirror_softc *sc)
1300 {
1301         struct bio *bp, *bp2;
1302
1303         TAILQ_FOREACH_SAFE(bp, &sc->sc_sync_delayed, bio_queue, bp2) {
1304                 if (g_mirror_regular_collision(sc, bp))
1305                         continue;
1306                 TAILQ_REMOVE(&sc->sc_sync_delayed, bp, bio_queue);
1307                 G_MIRROR_LOGREQ(2, bp,
1308                     "Releasing delayed synchronization request.");
1309                 g_io_request(bp, bp->bio_from);
1310         }
1311 }
1312
1313 /*
1314  * Free a synchronization request and clear its slot in the array.
1315  */
1316 static void
1317 g_mirror_sync_request_free(struct g_mirror_disk *disk, struct bio *bp)
1318 {
1319         int idx;
1320
1321         if (disk != NULL && disk->d_sync.ds_bios != NULL) {
1322                 idx = (int)(uintptr_t)bp->bio_caller1;
1323                 KASSERT(disk->d_sync.ds_bios[idx] == bp,
1324                     ("unexpected sync BIO at %p:%d", disk, idx));
1325                 disk->d_sync.ds_bios[idx] = NULL;
1326         }
1327         free(bp->bio_data, M_MIRROR);
1328         g_destroy_bio(bp);
1329 }
1330
1331 /*
1332  * Handle synchronization requests.
1333  * Every synchronization request is a two-step process: first, a read request is
1334  * sent to the mirror provider via the sync consumer. If that request completes
1335  * successfully, it is converted to a write and sent to the disk being
1336  * synchronized. If the write also completes successfully, the synchronization
1337  * offset is advanced and a new read request is submitted.
1338  */
1339 static void
1340 g_mirror_sync_request(struct g_mirror_softc *sc, struct bio *bp)
1341 {
1342         struct g_mirror_disk *disk;
1343         struct g_mirror_disk_sync *sync;
1344
1345         KASSERT((bp->bio_cmd == BIO_READ &&
1346             bp->bio_from->geom == sc->sc_sync.ds_geom) ||
1347             (bp->bio_cmd == BIO_WRITE && bp->bio_from->geom == sc->sc_geom),
1348             ("Sync BIO %p with unexpected origin", bp));
1349
1350         bp->bio_from->index--;
1351         disk = bp->bio_from->private;
1352         if (disk == NULL) {
1353                 sx_xunlock(&sc->sc_lock); /* Avoid recursion on sc_lock. */
1354                 g_topology_lock();
1355                 g_mirror_kill_consumer(sc, bp->bio_from);
1356                 g_topology_unlock();
1357                 g_mirror_sync_request_free(NULL, bp);
1358                 sx_xlock(&sc->sc_lock);
1359                 return;
1360         }
1361
1362         sync = &disk->d_sync;
1363
1364         /*
1365          * Synchronization request.
1366          */
1367         switch (bp->bio_cmd) {
1368         case BIO_READ: {
1369                 struct g_consumer *cp;
1370
1371                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_sync_request_read,
1372                     bp->bio_error);
1373
1374                 if (bp->bio_error != 0) {
1375                         G_MIRROR_LOGREQ(0, bp,
1376                             "Synchronization request failed (error=%d).",
1377                             bp->bio_error);
1378
1379                         /*
1380                          * The read error will trigger a syncid bump, so there's
1381                          * no need to do that here.
1382                          *
1383                          * The read error handling for regular requests will
1384                          * retry the read from all active mirrors before passing
1385                          * the error back up, so there's no need to retry here.
1386                          */
1387                         g_mirror_sync_request_free(disk, bp);
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,
1394                     "Synchronization request half-finished.");
1395                 bp->bio_cmd = BIO_WRITE;
1396                 bp->bio_cflags = 0;
1397                 cp = disk->d_consumer;
1398                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1399                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1400                     cp->acr, cp->acw, cp->ace));
1401                 cp->index++;
1402                 g_io_request(bp, cp);
1403                 return;
1404         }
1405         case BIO_WRITE: {
1406                 off_t offset;
1407                 int i;
1408
1409                 KFAIL_POINT_ERROR(DEBUG_FP, g_mirror_sync_request_write,
1410                     bp->bio_error);
1411
1412                 if (bp->bio_error != 0) {
1413                         G_MIRROR_LOGREQ(0, bp,
1414                             "Synchronization request failed (error=%d).",
1415                             bp->bio_error);
1416                         g_mirror_sync_request_free(disk, bp);
1417                         sc->sc_bump_id |= G_MIRROR_BUMP_GENID;
1418                         g_mirror_event_send(disk,
1419                             G_MIRROR_DISK_STATE_DISCONNECTED,
1420                             G_MIRROR_EVENT_DONTWAIT);
1421                         return;
1422                 }
1423                 G_MIRROR_LOGREQ(3, bp, "Synchronization request finished.");
1424                 if (sync->ds_offset >= sc->sc_mediasize ||
1425                     sync->ds_consumer == NULL ||
1426                     (sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1427                         /* Don't send more synchronization requests. */
1428                         sync->ds_inflight--;
1429                         g_mirror_sync_request_free(disk, bp);
1430                         if (sync->ds_inflight > 0)
1431                                 return;
1432                         if (sync->ds_consumer == NULL ||
1433                             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1434                                 return;
1435                         }
1436                         /* Disk up-to-date, activate it. */
1437                         g_mirror_event_send(disk, G_MIRROR_DISK_STATE_ACTIVE,
1438                             G_MIRROR_EVENT_DONTWAIT);
1439                         return;
1440                 }
1441
1442                 /* Send next synchronization request. */
1443                 g_mirror_sync_reinit(disk, bp, sync->ds_offset);
1444                 sync->ds_offset += bp->bio_length;
1445
1446                 G_MIRROR_LOGREQ(3, bp, "Sending synchronization request.");
1447                 sync->ds_consumer->index++;
1448
1449                 /*
1450                  * Delay the request if it is colliding with a regular request.
1451                  */
1452                 if (g_mirror_regular_collision(sc, bp))
1453                         g_mirror_sync_delay(sc, bp);
1454                 else
1455                         g_io_request(bp, sync->ds_consumer);
1456
1457                 /* Requeue delayed requests if possible. */
1458                 g_mirror_regular_release(sc);
1459
1460                 /* Find the smallest offset */
1461                 offset = sc->sc_mediasize;
1462                 for (i = 0; i < g_mirror_syncreqs; i++) {
1463                         bp = sync->ds_bios[i];
1464                         if (bp != NULL && bp->bio_offset < offset)
1465                                 offset = bp->bio_offset;
1466                 }
1467                 if (g_mirror_sync_period > 0 &&
1468                     time_uptime - sync->ds_update_ts > g_mirror_sync_period) {
1469                         sync->ds_offset_done = offset;
1470                         g_mirror_update_metadata(disk);
1471                         sync->ds_update_ts = time_uptime;
1472                 }
1473                 return;
1474         }
1475         default:
1476                 panic("Invalid I/O request %p", bp);
1477         }
1478 }
1479
1480 static void
1481 g_mirror_request_prefer(struct g_mirror_softc *sc, struct bio *bp)
1482 {
1483         struct g_mirror_disk *disk;
1484         struct g_consumer *cp;
1485         struct bio *cbp;
1486
1487         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1488                 if (disk->d_state == G_MIRROR_DISK_STATE_ACTIVE)
1489                         break;
1490         }
1491         if (disk == NULL) {
1492                 if (bp->bio_error == 0)
1493                         bp->bio_error = ENXIO;
1494                 g_io_deliver(bp, bp->bio_error);
1495                 return;
1496         }
1497         cbp = g_clone_bio(bp);
1498         if (cbp == NULL) {
1499                 if (bp->bio_error == 0)
1500                         bp->bio_error = ENOMEM;
1501                 g_io_deliver(bp, bp->bio_error);
1502                 return;
1503         }
1504         /*
1505          * Fill in the component buf structure.
1506          */
1507         cp = disk->d_consumer;
1508         cbp->bio_done = g_mirror_done;
1509         cbp->bio_to = cp->provider;
1510         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1511         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1512             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1513             cp->acw, cp->ace));
1514         cp->index++;
1515         g_io_request(cbp, cp);
1516 }
1517
1518 static void
1519 g_mirror_request_round_robin(struct g_mirror_softc *sc, struct bio *bp)
1520 {
1521         struct g_mirror_disk *disk;
1522         struct g_consumer *cp;
1523         struct bio *cbp;
1524
1525         disk = g_mirror_get_disk(sc);
1526         if (disk == NULL) {
1527                 if (bp->bio_error == 0)
1528                         bp->bio_error = ENXIO;
1529                 g_io_deliver(bp, bp->bio_error);
1530                 return;
1531         }
1532         cbp = g_clone_bio(bp);
1533         if (cbp == NULL) {
1534                 if (bp->bio_error == 0)
1535                         bp->bio_error = ENOMEM;
1536                 g_io_deliver(bp, bp->bio_error);
1537                 return;
1538         }
1539         /*
1540          * Fill in the component buf structure.
1541          */
1542         cp = disk->d_consumer;
1543         cbp->bio_done = g_mirror_done;
1544         cbp->bio_to = cp->provider;
1545         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1546         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1547             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1548             cp->acw, cp->ace));
1549         cp->index++;
1550         g_io_request(cbp, cp);
1551 }
1552
1553 #define TRACK_SIZE  (1 * 1024 * 1024)
1554 #define LOAD_SCALE      256
1555 #define ABS(x)          (((x) >= 0) ? (x) : (-(x)))
1556
1557 static void
1558 g_mirror_request_load(struct g_mirror_softc *sc, struct bio *bp)
1559 {
1560         struct g_mirror_disk *disk, *dp;
1561         struct g_consumer *cp;
1562         struct bio *cbp;
1563         int prio, best;
1564
1565         /* Find a disk with the smallest load. */
1566         disk = NULL;
1567         best = INT_MAX;
1568         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
1569                 if (dp->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1570                         continue;
1571                 prio = dp->load;
1572                 /* If disk head is precisely in position - highly prefer it. */
1573                 if (dp->d_last_offset == bp->bio_offset)
1574                         prio -= 2 * LOAD_SCALE;
1575                 else
1576                 /* If disk head is close to position - prefer it. */
1577                 if (ABS(dp->d_last_offset - bp->bio_offset) < TRACK_SIZE)
1578                         prio -= 1 * LOAD_SCALE;
1579                 if (prio <= best) {
1580                         disk = dp;
1581                         best = prio;
1582                 }
1583         }
1584         KASSERT(disk != NULL, ("NULL disk for %s.", sc->sc_name));
1585         cbp = g_clone_bio(bp);
1586         if (cbp == NULL) {
1587                 if (bp->bio_error == 0)
1588                         bp->bio_error = ENOMEM;
1589                 g_io_deliver(bp, bp->bio_error);
1590                 return;
1591         }
1592         /*
1593          * Fill in the component buf structure.
1594          */
1595         cp = disk->d_consumer;
1596         cbp->bio_done = g_mirror_done;
1597         cbp->bio_to = cp->provider;
1598         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1599         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1600             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name, cp->acr,
1601             cp->acw, cp->ace));
1602         cp->index++;
1603         /* Remember last head position */
1604         disk->d_last_offset = bp->bio_offset + bp->bio_length;
1605         /* Update loads. */
1606         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
1607                 dp->load = (dp->d_consumer->index * LOAD_SCALE +
1608                     dp->load * 7) / 8;
1609         }
1610         g_io_request(cbp, cp);
1611 }
1612
1613 static void
1614 g_mirror_request_split(struct g_mirror_softc *sc, struct bio *bp)
1615 {
1616         struct bio_queue queue;
1617         struct g_mirror_disk *disk;
1618         struct g_consumer *cp __diagused;
1619         struct bio *cbp;
1620         off_t left, mod, offset, slice;
1621         u_char *data;
1622         u_int ndisks;
1623
1624         if (bp->bio_length <= sc->sc_slice) {
1625                 g_mirror_request_round_robin(sc, bp);
1626                 return;
1627         }
1628         ndisks = g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE);
1629         slice = bp->bio_length / ndisks;
1630         mod = slice % sc->sc_provider->sectorsize;
1631         if (mod != 0)
1632                 slice += sc->sc_provider->sectorsize - mod;
1633         /*
1634          * Allocate all bios before sending any request, so we can
1635          * return ENOMEM in nice and clean way.
1636          */
1637         left = bp->bio_length;
1638         offset = bp->bio_offset;
1639         data = bp->bio_data;
1640         TAILQ_INIT(&queue);
1641         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1642                 if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1643                         continue;
1644                 cbp = g_clone_bio(bp);
1645                 if (cbp == NULL) {
1646                         while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1647                                 TAILQ_REMOVE(&queue, cbp, bio_queue);
1648                                 g_destroy_bio(cbp);
1649                         }
1650                         if (bp->bio_error == 0)
1651                                 bp->bio_error = ENOMEM;
1652                         g_io_deliver(bp, bp->bio_error);
1653                         return;
1654                 }
1655                 TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1656                 cbp->bio_done = g_mirror_done;
1657                 cbp->bio_caller1 = disk;
1658                 cbp->bio_to = disk->d_consumer->provider;
1659                 cbp->bio_offset = offset;
1660                 cbp->bio_data = data;
1661                 cbp->bio_length = MIN(left, slice);
1662                 left -= cbp->bio_length;
1663                 if (left == 0)
1664                         break;
1665                 offset += cbp->bio_length;
1666                 data += cbp->bio_length;
1667         }
1668         while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1669                 TAILQ_REMOVE(&queue, cbp, bio_queue);
1670                 G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1671                 disk = cbp->bio_caller1;
1672                 cbp->bio_caller1 = NULL;
1673                 cp = disk->d_consumer;
1674                 KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1675                     ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1676                     cp->acr, cp->acw, cp->ace));
1677                 disk->d_consumer->index++;
1678                 g_io_request(cbp, disk->d_consumer);
1679         }
1680 }
1681
1682 static void
1683 g_mirror_register_request(struct g_mirror_softc *sc, struct bio *bp)
1684 {
1685         struct bio_queue queue;
1686         struct bio *cbp;
1687         struct g_consumer *cp;
1688         struct g_mirror_disk *disk;
1689
1690         sx_assert(&sc->sc_lock, SA_XLOCKED);
1691
1692         /*
1693          * To avoid ordering issues, if a write is deferred because of a
1694          * collision with a sync request, all I/O is deferred until that
1695          * write is initiated.
1696          */
1697         if (bp->bio_from->geom != sc->sc_sync.ds_geom &&
1698             !TAILQ_EMPTY(&sc->sc_regular_delayed)) {
1699                 g_mirror_regular_delay(sc, bp);
1700                 return;
1701         }
1702
1703         switch (bp->bio_cmd) {
1704         case BIO_READ:
1705                 switch (sc->sc_balance) {
1706                 case G_MIRROR_BALANCE_LOAD:
1707                         g_mirror_request_load(sc, bp);
1708                         break;
1709                 case G_MIRROR_BALANCE_PREFER:
1710                         g_mirror_request_prefer(sc, bp);
1711                         break;
1712                 case G_MIRROR_BALANCE_ROUND_ROBIN:
1713                         g_mirror_request_round_robin(sc, bp);
1714                         break;
1715                 case G_MIRROR_BALANCE_SPLIT:
1716                         g_mirror_request_split(sc, bp);
1717                         break;
1718                 }
1719                 return;
1720         case BIO_WRITE:
1721         case BIO_DELETE:
1722                 /*
1723                  * Delay the request if it is colliding with a synchronization
1724                  * request.
1725                  */
1726                 if (g_mirror_sync_collision(sc, bp)) {
1727                         g_mirror_regular_delay(sc, bp);
1728                         return;
1729                 }
1730
1731                 if (sc->sc_idle)
1732                         g_mirror_unidle(sc);
1733                 else
1734                         sc->sc_last_write = time_uptime;
1735
1736                 /*
1737                  * Bump syncid on first write.
1738                  */
1739                 if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID) != 0) {
1740                         sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID;
1741                         g_mirror_bump_syncid(sc);
1742                 }
1743
1744                 /*
1745                  * Allocate all bios before sending any request, so we can
1746                  * return ENOMEM in nice and clean way.
1747                  */
1748                 TAILQ_INIT(&queue);
1749                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1750                         switch (disk->d_state) {
1751                         case G_MIRROR_DISK_STATE_ACTIVE:
1752                                 break;
1753                         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
1754                                 if (bp->bio_offset >= disk->d_sync.ds_offset)
1755                                         continue;
1756                                 break;
1757                         default:
1758                                 continue;
1759                         }
1760                         if (bp->bio_cmd == BIO_DELETE &&
1761                             (disk->d_flags & G_MIRROR_DISK_FLAG_CANDELETE) == 0)
1762                                 continue;
1763                         cbp = g_clone_bio(bp);
1764                         if (cbp == NULL) {
1765                                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1766                                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1767                                         g_destroy_bio(cbp);
1768                                 }
1769                                 if (bp->bio_error == 0)
1770                                         bp->bio_error = ENOMEM;
1771                                 g_io_deliver(bp, bp->bio_error);
1772                                 return;
1773                         }
1774                         TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1775                         cbp->bio_done = g_mirror_done;
1776                         cp = disk->d_consumer;
1777                         cbp->bio_caller1 = cp;
1778                         cbp->bio_to = cp->provider;
1779                         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1780                             ("Consumer %s not opened (r%dw%de%d).",
1781                             cp->provider->name, cp->acr, cp->acw, cp->ace));
1782                 }
1783                 if (TAILQ_EMPTY(&queue)) {
1784                         KASSERT(bp->bio_cmd == BIO_DELETE,
1785                             ("No consumers for regular request %p", bp));
1786                         g_io_deliver(bp, EOPNOTSUPP);
1787                         return;
1788                 }
1789                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1790                         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1791                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1792                         cp = cbp->bio_caller1;
1793                         cbp->bio_caller1 = NULL;
1794                         cp->index++;
1795                         sc->sc_writes++;
1796                         g_io_request(cbp, cp);
1797                 }
1798                 /*
1799                  * Put request onto inflight queue, so we can check if new
1800                  * synchronization requests don't collide with it.
1801                  */
1802                 TAILQ_INSERT_TAIL(&sc->sc_inflight, bp, bio_queue);
1803                 return;
1804         case BIO_SPEEDUP:
1805         case BIO_FLUSH:
1806                 TAILQ_INIT(&queue);
1807                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
1808                         if (disk->d_state != G_MIRROR_DISK_STATE_ACTIVE)
1809                                 continue;
1810                         cbp = g_clone_bio(bp);
1811                         if (cbp == NULL) {
1812                                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1813                                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1814                                         g_destroy_bio(cbp);
1815                                 }
1816                                 if (bp->bio_error == 0)
1817                                         bp->bio_error = ENOMEM;
1818                                 g_io_deliver(bp, bp->bio_error);
1819                                 return;
1820                         }
1821                         TAILQ_INSERT_TAIL(&queue, cbp, bio_queue);
1822                         cbp->bio_done = g_mirror_done;
1823                         cbp->bio_caller1 = disk;
1824                         cbp->bio_to = disk->d_consumer->provider;
1825                 }
1826                 KASSERT(!TAILQ_EMPTY(&queue),
1827                     ("No consumers for regular request %p", bp));
1828                 while ((cbp = TAILQ_FIRST(&queue)) != NULL) {
1829                         G_MIRROR_LOGREQ(3, cbp, "Sending request.");
1830                         TAILQ_REMOVE(&queue, cbp, bio_queue);
1831                         disk = cbp->bio_caller1;
1832                         cbp->bio_caller1 = NULL;
1833                         cp = disk->d_consumer;
1834                         KASSERT(cp->acr >= 1 && cp->acw >= 1 && cp->ace >= 1,
1835                             ("Consumer %s not opened (r%dw%de%d).", cp->provider->name,
1836                             cp->acr, cp->acw, cp->ace));
1837                         cp->index++;
1838                         g_io_request(cbp, cp);
1839                 }
1840                 break;
1841         default:
1842                 KASSERT(1 == 0, ("Invalid command here: %u (device=%s)",
1843                     bp->bio_cmd, sc->sc_name));
1844                 break;
1845         }
1846 }
1847
1848 static int
1849 g_mirror_can_destroy(struct g_mirror_softc *sc)
1850 {
1851         struct g_geom *gp;
1852         struct g_consumer *cp;
1853
1854         g_topology_assert();
1855         gp = sc->sc_geom;
1856         if (gp->softc == NULL)
1857                 return (1);
1858         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_TASTING) != 0)
1859                 return (0);
1860         LIST_FOREACH(cp, &gp->consumer, consumer) {
1861                 if (g_mirror_is_busy(sc, cp))
1862                         return (0);
1863         }
1864         gp = sc->sc_sync.ds_geom;
1865         LIST_FOREACH(cp, &gp->consumer, consumer) {
1866                 if (g_mirror_is_busy(sc, cp))
1867                         return (0);
1868         }
1869         G_MIRROR_DEBUG(2, "No I/O requests for %s, it can be destroyed.",
1870             sc->sc_name);
1871         return (1);
1872 }
1873
1874 static int
1875 g_mirror_try_destroy(struct g_mirror_softc *sc)
1876 {
1877
1878         if (sc->sc_rootmount != NULL) {
1879                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p", __LINE__,
1880                     sc->sc_rootmount);
1881                 root_mount_rel(sc->sc_rootmount);
1882                 sc->sc_rootmount = NULL;
1883         }
1884         g_topology_lock();
1885         if (!g_mirror_can_destroy(sc)) {
1886                 g_topology_unlock();
1887                 return (0);
1888         }
1889         sc->sc_geom->softc = NULL;
1890         sc->sc_sync.ds_geom->softc = NULL;
1891         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DRAIN) != 0) {
1892                 g_topology_unlock();
1893                 G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__,
1894                     &sc->sc_worker);
1895                 /* Unlock sc_lock here, as it can be destroyed after wakeup. */
1896                 sx_xunlock(&sc->sc_lock);
1897                 wakeup(&sc->sc_worker);
1898                 sc->sc_worker = NULL;
1899         } else {
1900                 g_topology_unlock();
1901                 g_mirror_destroy_device(sc);
1902         }
1903         return (1);
1904 }
1905
1906 /*
1907  * Worker thread.
1908  */
1909 static void
1910 g_mirror_worker(void *arg)
1911 {
1912         struct g_mirror_softc *sc;
1913         struct g_mirror_event *ep;
1914         struct bio *bp;
1915         int timeout;
1916
1917         sc = arg;
1918         thread_lock(curthread);
1919         sched_prio(curthread, PRIBIO);
1920         thread_unlock(curthread);
1921
1922         sx_xlock(&sc->sc_lock);
1923         for (;;) {
1924                 G_MIRROR_DEBUG(5, "%s: Let's see...", __func__);
1925                 /*
1926                  * First take a look at events.
1927                  * This is important to handle events before any I/O requests.
1928                  */
1929                 ep = g_mirror_event_first(sc);
1930                 if (ep != NULL) {
1931                         g_mirror_event_remove(sc, ep);
1932                         if ((ep->e_flags & G_MIRROR_EVENT_DEVICE) != 0) {
1933                                 /* Update only device status. */
1934                                 G_MIRROR_DEBUG(3,
1935                                     "Running event for device %s.",
1936                                     sc->sc_name);
1937                                 ep->e_error = 0;
1938                                 g_mirror_update_device(sc, true);
1939                         } else {
1940                                 /* Update disk status. */
1941                                 G_MIRROR_DEBUG(3, "Running event for disk %s.",
1942                                      g_mirror_get_diskname(ep->e_disk));
1943                                 ep->e_error = g_mirror_update_disk(ep->e_disk,
1944                                     ep->e_state);
1945                                 if (ep->e_error == 0)
1946                                         g_mirror_update_device(sc, false);
1947                         }
1948                         if ((ep->e_flags & G_MIRROR_EVENT_DONTWAIT) != 0) {
1949                                 KASSERT(ep->e_error == 0,
1950                                     ("Error cannot be handled."));
1951                                 g_mirror_event_free(ep);
1952                         } else {
1953                                 ep->e_flags |= G_MIRROR_EVENT_DONE;
1954                                 G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__,
1955                                     ep);
1956                                 mtx_lock(&sc->sc_events_mtx);
1957                                 wakeup(ep);
1958                                 mtx_unlock(&sc->sc_events_mtx);
1959                         }
1960                         if ((sc->sc_flags &
1961                             G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1962                                 if (g_mirror_try_destroy(sc)) {
1963                                         curthread->td_pflags &= ~TDP_GEOM;
1964                                         G_MIRROR_DEBUG(1, "Thread exiting.");
1965                                         kproc_exit(0);
1966                                 }
1967                         }
1968                         G_MIRROR_DEBUG(5, "%s: I'm here 1.", __func__);
1969                         continue;
1970                 }
1971
1972                 /*
1973                  * Check if we can mark array as CLEAN and if we can't take
1974                  * how much seconds should we wait.
1975                  */
1976                 timeout = g_mirror_idle(sc, -1);
1977
1978                 /*
1979                  * Handle I/O requests.
1980                  */
1981                 mtx_lock(&sc->sc_queue_mtx);
1982                 bp = TAILQ_FIRST(&sc->sc_queue);
1983                 if (bp != NULL)
1984                         TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue);
1985                 else {
1986                         if ((sc->sc_flags &
1987                             G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
1988                                 mtx_unlock(&sc->sc_queue_mtx);
1989                                 if (g_mirror_try_destroy(sc)) {
1990                                         curthread->td_pflags &= ~TDP_GEOM;
1991                                         G_MIRROR_DEBUG(1, "Thread exiting.");
1992                                         kproc_exit(0);
1993                                 }
1994                                 mtx_lock(&sc->sc_queue_mtx);
1995                                 if (!TAILQ_EMPTY(&sc->sc_queue)) {
1996                                         mtx_unlock(&sc->sc_queue_mtx);
1997                                         continue;
1998                                 }
1999                         }
2000                         if (g_mirror_event_first(sc) != NULL) {
2001                                 mtx_unlock(&sc->sc_queue_mtx);
2002                                 continue;
2003                         }
2004                         sx_xunlock(&sc->sc_lock);
2005                         MSLEEP(sc, &sc->sc_queue_mtx, PRIBIO | PDROP, "m:w1",
2006                             timeout * hz);
2007                         sx_xlock(&sc->sc_lock);
2008                         G_MIRROR_DEBUG(5, "%s: I'm here 4.", __func__);
2009                         continue;
2010                 }
2011                 mtx_unlock(&sc->sc_queue_mtx);
2012
2013                 if (bp->bio_from->geom == sc->sc_sync.ds_geom &&
2014                     (bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0) {
2015                         /*
2016                          * Handle completion of the first half (the read) of a
2017                          * block synchronization operation.
2018                          */
2019                         g_mirror_sync_request(sc, bp);
2020                 } else if (bp->bio_to != sc->sc_provider) {
2021                         if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_REGULAR) != 0)
2022                                 /*
2023                                  * Handle completion of a regular I/O request.
2024                                  */
2025                                 g_mirror_regular_request(sc, bp);
2026                         else if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0)
2027                                 /*
2028                                  * Handle completion of the second half (the
2029                                  * write) of a block synchronization operation.
2030                                  */
2031                                 g_mirror_sync_request(sc, bp);
2032                         else {
2033                                 KASSERT(0,
2034                                     ("Invalid request cflags=0x%hx to=%s.",
2035                                     bp->bio_cflags, bp->bio_to->name));
2036                         }
2037                 } else {
2038                         /*
2039                          * Initiate an I/O request.
2040                          */
2041                         g_mirror_register_request(sc, bp);
2042                 }
2043                 G_MIRROR_DEBUG(5, "%s: I'm here 9.", __func__);
2044         }
2045 }
2046
2047 static void
2048 g_mirror_update_idle(struct g_mirror_softc *sc, struct g_mirror_disk *disk)
2049 {
2050
2051         sx_assert(&sc->sc_lock, SX_LOCKED);
2052
2053         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) != 0)
2054                 return;
2055         if (!sc->sc_idle && (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) == 0) {
2056                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as dirty.",
2057                     g_mirror_get_diskname(disk), sc->sc_name);
2058                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
2059         } else if (sc->sc_idle &&
2060             (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) != 0) {
2061                 G_MIRROR_DEBUG(2, "Disk %s (device %s) marked as clean.",
2062                     g_mirror_get_diskname(disk), sc->sc_name);
2063                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2064         }
2065 }
2066
2067 static void
2068 g_mirror_sync_reinit(const struct g_mirror_disk *disk, struct bio *bp,
2069     off_t offset)
2070 {
2071         void *data;
2072         int idx;
2073
2074         data = bp->bio_data;
2075         idx = (int)(uintptr_t)bp->bio_caller1;
2076         g_reset_bio(bp);
2077
2078         bp->bio_cmd = BIO_READ;
2079         bp->bio_data = data;
2080         bp->bio_done = g_mirror_sync_done;
2081         bp->bio_from = disk->d_sync.ds_consumer;
2082         bp->bio_to = disk->d_softc->sc_provider;
2083         bp->bio_caller1 = (void *)(uintptr_t)idx;
2084         bp->bio_offset = offset;
2085         bp->bio_length = MIN(maxphys,
2086             disk->d_softc->sc_mediasize - bp->bio_offset);
2087 }
2088
2089 static void
2090 g_mirror_sync_start(struct g_mirror_disk *disk)
2091 {
2092         struct g_mirror_softc *sc;
2093         struct g_mirror_disk_sync *sync;
2094         struct g_consumer *cp;
2095         struct bio *bp;
2096         int error __diagused, i;
2097
2098         g_topology_assert_not();
2099         sc = disk->d_softc;
2100         sync = &disk->d_sync;
2101         sx_assert(&sc->sc_lock, SX_LOCKED);
2102
2103         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2104             ("Disk %s is not marked for synchronization.",
2105             g_mirror_get_diskname(disk)));
2106         KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2107             ("Device not in RUNNING state (%s, %u).", sc->sc_name,
2108             sc->sc_state));
2109
2110         sx_xunlock(&sc->sc_lock);
2111         g_topology_lock();
2112         cp = g_new_consumer(sc->sc_sync.ds_geom);
2113         cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE;
2114         error = g_attach(cp, sc->sc_provider);
2115         KASSERT(error == 0,
2116             ("Cannot attach to %s (error=%d).", sc->sc_name, error));
2117         error = g_access(cp, 1, 0, 0);
2118         KASSERT(error == 0, ("Cannot open %s (error=%d).", sc->sc_name, error));
2119         g_topology_unlock();
2120         sx_xlock(&sc->sc_lock);
2121
2122         G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s.", sc->sc_name,
2123             g_mirror_get_diskname(disk));
2124         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOFAILSYNC) == 0)
2125                 disk->d_flags |= G_MIRROR_DISK_FLAG_DIRTY;
2126         KASSERT(sync->ds_consumer == NULL,
2127             ("Sync consumer already exists (device=%s, disk=%s).",
2128             sc->sc_name, g_mirror_get_diskname(disk)));
2129
2130         sync->ds_consumer = cp;
2131         sync->ds_consumer->private = disk;
2132         sync->ds_consumer->index = 0;
2133
2134         /*
2135          * Allocate memory for synchronization bios and initialize them.
2136          */
2137         sync->ds_bios = malloc(sizeof(struct bio *) * g_mirror_syncreqs,
2138             M_MIRROR, M_WAITOK);
2139         for (i = 0; i < g_mirror_syncreqs; i++) {
2140                 bp = g_alloc_bio();
2141                 sync->ds_bios[i] = bp;
2142
2143                 bp->bio_data = malloc(maxphys, M_MIRROR, M_WAITOK);
2144                 bp->bio_caller1 = (void *)(uintptr_t)i;
2145                 g_mirror_sync_reinit(disk, bp, sync->ds_offset);
2146                 sync->ds_offset += bp->bio_length;
2147         }
2148
2149         /* Increase the number of disks in SYNCHRONIZING state. */
2150         sc->sc_sync.ds_ndisks++;
2151         /* Set the number of in-flight synchronization requests. */
2152         sync->ds_inflight = g_mirror_syncreqs;
2153
2154         /*
2155          * Fire off first synchronization requests.
2156          */
2157         for (i = 0; i < g_mirror_syncreqs; i++) {
2158                 bp = sync->ds_bios[i];
2159                 G_MIRROR_LOGREQ(3, bp, "Sending synchronization request.");
2160                 sync->ds_consumer->index++;
2161                 /*
2162                  * Delay the request if it is colliding with a regular request.
2163                  */
2164                 if (g_mirror_regular_collision(sc, bp))
2165                         g_mirror_sync_delay(sc, bp);
2166                 else
2167                         g_io_request(bp, sync->ds_consumer);
2168         }
2169 }
2170
2171 /*
2172  * Stop synchronization process.
2173  * type: 0 - synchronization finished
2174  *       1 - synchronization stopped
2175  */
2176 static void
2177 g_mirror_sync_stop(struct g_mirror_disk *disk, int type)
2178 {
2179         struct g_mirror_softc *sc;
2180         struct g_consumer *cp;
2181
2182         g_topology_assert_not();
2183         sc = disk->d_softc;
2184         sx_assert(&sc->sc_lock, SX_LOCKED);
2185
2186         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2187             ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2188             g_mirror_disk_state2str(disk->d_state)));
2189         if (disk->d_sync.ds_consumer == NULL)
2190                 return;
2191
2192         if (type == 0) {
2193                 G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s finished.",
2194                     sc->sc_name, g_mirror_get_diskname(disk));
2195         } else /* if (type == 1) */ {
2196                 G_MIRROR_DEBUG(0, "Device %s: rebuilding provider %s stopped.",
2197                     sc->sc_name, g_mirror_get_diskname(disk));
2198         }
2199         g_mirror_regular_release(sc);
2200         free(disk->d_sync.ds_bios, M_MIRROR);
2201         disk->d_sync.ds_bios = NULL;
2202         cp = disk->d_sync.ds_consumer;
2203         disk->d_sync.ds_consumer = NULL;
2204         disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2205         sc->sc_sync.ds_ndisks--;
2206         sx_xunlock(&sc->sc_lock); /* Avoid recursion on sc_lock. */
2207         g_topology_lock();
2208         g_mirror_kill_consumer(sc, cp);
2209         g_topology_unlock();
2210         sx_xlock(&sc->sc_lock);
2211 }
2212
2213 static void
2214 g_mirror_launch_provider(struct g_mirror_softc *sc)
2215 {
2216         struct g_mirror_disk *disk;
2217         struct g_provider *pp, *dp;
2218
2219         sx_assert(&sc->sc_lock, SX_LOCKED);
2220
2221         g_topology_lock();
2222         pp = g_new_providerf(sc->sc_geom, "mirror/%s", sc->sc_name);
2223         pp->flags |= G_PF_DIRECT_RECEIVE;
2224         pp->mediasize = sc->sc_mediasize;
2225         pp->sectorsize = sc->sc_sectorsize;
2226         pp->stripesize = 0;
2227         pp->stripeoffset = 0;
2228
2229         /* Splitting of unmapped BIO's could work but isn't implemented now */
2230         if (sc->sc_balance != G_MIRROR_BALANCE_SPLIT)
2231                 pp->flags |= G_PF_ACCEPT_UNMAPPED;
2232
2233         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2234                 if (disk->d_consumer && disk->d_consumer->provider) {
2235                         dp = disk->d_consumer->provider;
2236                         if (dp->stripesize > pp->stripesize) {
2237                                 pp->stripesize = dp->stripesize;
2238                                 pp->stripeoffset = dp->stripeoffset;
2239                         }
2240                         /* A provider underneath us doesn't support unmapped */
2241                         if ((dp->flags & G_PF_ACCEPT_UNMAPPED) == 0) {
2242                                 G_MIRROR_DEBUG(0, "Cancelling unmapped "
2243                                     "because of %s.", dp->name);
2244                                 pp->flags &= ~G_PF_ACCEPT_UNMAPPED;
2245                         }
2246                 }
2247         }
2248         pp->private = sc;
2249         sc->sc_refcnt++;
2250         sc->sc_provider = pp;
2251         g_error_provider(pp, 0);
2252         g_topology_unlock();
2253         G_MIRROR_DEBUG(0, "Device %s launched (%u/%u).", pp->name,
2254             g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE), sc->sc_ndisks);
2255         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2256                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
2257                         g_mirror_sync_start(disk);
2258         }
2259 }
2260
2261 static void
2262 g_mirror_destroy_provider(struct g_mirror_softc *sc)
2263 {
2264         struct g_mirror_disk *disk;
2265         struct bio *bp;
2266
2267         g_topology_assert_not();
2268         KASSERT(sc->sc_provider != NULL, ("NULL provider (device=%s).",
2269             sc->sc_name));
2270
2271         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2272                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING)
2273                         g_mirror_sync_stop(disk, 1);
2274         }
2275
2276         g_topology_lock();
2277         g_error_provider(sc->sc_provider, ENXIO);
2278         mtx_lock(&sc->sc_queue_mtx);
2279         while ((bp = TAILQ_FIRST(&sc->sc_queue)) != NULL) {
2280                 TAILQ_REMOVE(&sc->sc_queue, bp, bio_queue);
2281                 /*
2282                  * Abort any pending I/O that wasn't generated by us.
2283                  * Synchronization requests and requests destined for individual
2284                  * mirror components can be destroyed immediately.
2285                  */
2286                 if (bp->bio_to == sc->sc_provider &&
2287                     bp->bio_from->geom != sc->sc_sync.ds_geom) {
2288                         g_io_deliver(bp, ENXIO);
2289                 } else {
2290                         if ((bp->bio_cflags & G_MIRROR_BIO_FLAG_SYNC) != 0)
2291                                 free(bp->bio_data, M_MIRROR);
2292                         g_destroy_bio(bp);
2293                 }
2294         }
2295         mtx_unlock(&sc->sc_queue_mtx);
2296         g_wither_provider(sc->sc_provider, ENXIO);
2297         sc->sc_provider = NULL;
2298         G_MIRROR_DEBUG(0, "Device %s: provider destroyed.", sc->sc_name);
2299         g_topology_unlock();
2300 }
2301
2302 static void
2303 g_mirror_go(void *arg)
2304 {
2305         struct g_mirror_softc *sc;
2306         struct g_mirror_event *ep;
2307
2308         sc = arg;
2309         G_MIRROR_DEBUG(0, "Force device %s start due to timeout.", sc->sc_name);
2310         ep = sc->sc_timeout_event;
2311         sc->sc_timeout_event = NULL;
2312         g_mirror_event_dispatch(ep, sc, 0,
2313             G_MIRROR_EVENT_DONTWAIT | G_MIRROR_EVENT_DEVICE);
2314 }
2315
2316 static void
2317 g_mirror_timeout_drain(struct g_mirror_softc *sc)
2318 {
2319         sx_assert(&sc->sc_lock, SX_XLOCKED);
2320
2321         callout_drain(&sc->sc_callout);
2322         g_mirror_event_free(sc->sc_timeout_event);
2323         sc->sc_timeout_event = NULL;
2324 }
2325
2326 static u_int
2327 g_mirror_determine_state(struct g_mirror_disk *disk)
2328 {
2329         struct g_mirror_softc *sc;
2330         u_int state;
2331
2332         sc = disk->d_softc;
2333         if (sc->sc_syncid == disk->d_sync.ds_syncid) {
2334                 if ((disk->d_flags &
2335                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) == 0 &&
2336                     (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 0 ||
2337                      (disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) == 0)) {
2338                         /* Disk does not need synchronization. */
2339                         state = G_MIRROR_DISK_STATE_ACTIVE;
2340                 } else {
2341                         if ((sc->sc_flags &
2342                              G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) == 0 ||
2343                             (disk->d_flags &
2344                              G_MIRROR_DISK_FLAG_FORCE_SYNC) != 0) {
2345                                 /*
2346                                  * We can start synchronization from
2347                                  * the stored offset.
2348                                  */
2349                                 state = G_MIRROR_DISK_STATE_SYNCHRONIZING;
2350                         } else {
2351                                 state = G_MIRROR_DISK_STATE_STALE;
2352                         }
2353                 }
2354         } else if (disk->d_sync.ds_syncid < sc->sc_syncid) {
2355                 /*
2356                  * Reset all synchronization data for this disk,
2357                  * because if it even was synchronized, it was
2358                  * synchronized to disks with different syncid.
2359                  */
2360                 disk->d_flags |= G_MIRROR_DISK_FLAG_SYNCHRONIZING;
2361                 disk->d_sync.ds_offset = 0;
2362                 disk->d_sync.ds_offset_done = 0;
2363                 disk->d_sync.ds_syncid = sc->sc_syncid;
2364                 if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) == 0 ||
2365                     (disk->d_flags & G_MIRROR_DISK_FLAG_FORCE_SYNC) != 0) {
2366                         state = G_MIRROR_DISK_STATE_SYNCHRONIZING;
2367                 } else {
2368                         state = G_MIRROR_DISK_STATE_STALE;
2369                 }
2370         } else /* if (sc->sc_syncid < disk->d_sync.ds_syncid) */ {
2371                 /*
2372                  * Not good, NOT GOOD!
2373                  * It means that mirror was started on stale disks
2374                  * and more fresh disk just arrive.
2375                  * If there were writes, mirror is broken, sorry.
2376                  * I think the best choice here is don't touch
2377                  * this disk and inform the user loudly.
2378                  */
2379                 G_MIRROR_DEBUG(0, "Device %s was started before the freshest "
2380                     "disk (%s) arrives!! It will not be connected to the "
2381                     "running device.", sc->sc_name,
2382                     g_mirror_get_diskname(disk));
2383                 g_mirror_destroy_disk(disk);
2384                 state = G_MIRROR_DISK_STATE_NONE;
2385                 /* Return immediately, because disk was destroyed. */
2386                 return (state);
2387         }
2388         G_MIRROR_DEBUG(3, "State for %s disk: %s.",
2389             g_mirror_get_diskname(disk), g_mirror_disk_state2str(state));
2390         return (state);
2391 }
2392
2393 /*
2394  * Update device state.
2395  */
2396 static void
2397 g_mirror_update_device(struct g_mirror_softc *sc, bool force)
2398 {
2399         struct g_mirror_disk *disk;
2400         u_int state;
2401
2402         sx_assert(&sc->sc_lock, SX_XLOCKED);
2403
2404         switch (sc->sc_state) {
2405         case G_MIRROR_DEVICE_STATE_STARTING:
2406             {
2407                 struct g_mirror_disk *pdisk, *tdisk;
2408                 const char *mismatch;
2409                 uintmax_t found, newest;
2410                 u_int dirty, ndisks;
2411
2412                 /* Pre-flight checks */
2413                 LIST_FOREACH_SAFE(disk, &sc->sc_disks, d_next, tdisk) {
2414                         /*
2415                          * Confirm we already detected the newest genid.
2416                          */
2417                         KASSERT(sc->sc_genid >= disk->d_genid,
2418                             ("%s: found newer genid %u (sc:%p had %u).", __func__,
2419                             disk->d_genid, sc, sc->sc_genid));
2420
2421                         /* Kick out any previously tasted stale components. */
2422                         if (disk->d_genid < sc->sc_genid) {
2423                                 G_MIRROR_DEBUG(0, "Stale 'genid' field on %s "
2424                                     "(device %s) (component=%u latest=%u), skipping.",
2425                                     g_mirror_get_diskname(disk), sc->sc_name,
2426                                     disk->d_genid, sc->sc_genid);
2427                                 g_mirror_destroy_disk(disk);
2428                                 sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2429                                 continue;
2430                         }
2431
2432                         /*
2433                          * Confirm we already detected the newest syncid.
2434                          */
2435                         KASSERT(sc->sc_syncid >= disk->d_sync.ds_syncid,
2436                             ("%s: found newer syncid %u (sc:%p had %u).",
2437                              __func__, disk->d_sync.ds_syncid, sc,
2438                              sc->sc_syncid));
2439
2440 #define DETECT_MISMATCH(field, name) \
2441                         if (mismatch == NULL &&                                 \
2442                             disk->d_init_ ## field != sc->sc_ ## field) {       \
2443                                 mismatch = name;                                \
2444                                 found = (intmax_t)disk->d_init_ ## field;       \
2445                                 newest = (intmax_t)sc->sc_ ## field;            \
2446                         }
2447                         mismatch = NULL;
2448                         DETECT_MISMATCH(ndisks, "md_all");
2449                         DETECT_MISMATCH(balance, "md_balance");
2450                         DETECT_MISMATCH(slice, "md_slice");
2451                         DETECT_MISMATCH(mediasize, "md_mediasize");
2452 #undef DETECT_MISMATCH
2453                         if (mismatch != NULL) {
2454                                 G_MIRROR_DEBUG(0, "Found a mismatching '%s' "
2455                                     "field on %s (device %s) (found=%ju "
2456                                     "newest=%ju).", mismatch,
2457                                     g_mirror_get_diskname(disk), sc->sc_name,
2458                                     found, newest);
2459                                 g_mirror_destroy_disk(disk);
2460                                 sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2461                                 continue;
2462                         }
2463                 }
2464
2465                 KASSERT(sc->sc_provider == NULL,
2466                     ("Non-NULL provider in STARTING state (%s).", sc->sc_name));
2467                 /*
2468                  * Are we ready? If the timeout (force is true) has expired, and
2469                  * any disks are present, then yes. If we're permitted to launch
2470                  * before the timeout has expired and the expected number of
2471                  * current-generation mirror disks have been tasted, then yes.
2472                  */
2473                 ndisks = g_mirror_ndisks(sc, -1);
2474                 if ((force && ndisks > 0) ||
2475                     (g_launch_mirror_before_timeout && ndisks == sc->sc_ndisks)) {
2476                         ;
2477                 } else if (ndisks == 0) {
2478                         /*
2479                          * Disks went down in starting phase, so destroy
2480                          * device.
2481                          */
2482                         g_mirror_timeout_drain(sc);
2483                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2484                         G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p", __LINE__,
2485                             sc->sc_rootmount);
2486                         root_mount_rel(sc->sc_rootmount);
2487                         sc->sc_rootmount = NULL;
2488                         return;
2489                 } else {
2490                         return;
2491                 }
2492
2493                 /*
2494                  * Activate all disks with the biggest syncid.
2495                  */
2496                 if (force) {
2497                         /*
2498                          * If 'force' is true, we have been called due to
2499                          * timeout, so don't bother canceling timeout.
2500                          */
2501                         ndisks = 0;
2502                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2503                                 if ((disk->d_flags &
2504                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) == 0) {
2505                                         ndisks++;
2506                                 }
2507                         }
2508                         if (ndisks == 0) {
2509                                 /* No valid disks found, destroy device. */
2510                                 sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2511                                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p",
2512                                     __LINE__, sc->sc_rootmount);
2513                                 root_mount_rel(sc->sc_rootmount);
2514                                 sc->sc_rootmount = NULL;
2515                                 return;
2516                         }
2517                 } else {
2518                         /* Cancel timeout. */
2519                         g_mirror_timeout_drain(sc);
2520                 }
2521
2522                 /*
2523                  * Here we need to look for dirty disks and if all disks
2524                  * with the biggest syncid are dirty, we have to choose
2525                  * one with the biggest priority and rebuild the rest.
2526                  */
2527                 /*
2528                  * Find the number of dirty disks with the biggest syncid.
2529                  * Find the number of disks with the biggest syncid.
2530                  * While here, find a disk with the biggest priority.
2531                  */
2532                 dirty = ndisks = 0;
2533                 pdisk = NULL;
2534                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2535                         if (disk->d_sync.ds_syncid != sc->sc_syncid)
2536                                 continue;
2537                         if ((disk->d_flags &
2538                             G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2539                                 continue;
2540                         }
2541                         ndisks++;
2542                         if ((disk->d_flags & G_MIRROR_DISK_FLAG_DIRTY) != 0) {
2543                                 dirty++;
2544                                 if (pdisk == NULL ||
2545                                     pdisk->d_priority < disk->d_priority) {
2546                                         pdisk = disk;
2547                                 }
2548                         }
2549                 }
2550                 if (dirty == 0) {
2551                         /* No dirty disks at all, great. */
2552                 } else if (dirty == ndisks) {
2553                         /*
2554                          * Force synchronization for all dirty disks except one
2555                          * with the biggest priority.
2556                          */
2557                         KASSERT(pdisk != NULL, ("pdisk == NULL"));
2558                         G_MIRROR_DEBUG(1, "Using disk %s (device %s) as a "
2559                             "master disk for synchronization.",
2560                             g_mirror_get_diskname(pdisk), sc->sc_name);
2561                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2562                                 if (disk->d_sync.ds_syncid != sc->sc_syncid)
2563                                         continue;
2564                                 if ((disk->d_flags &
2565                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2566                                         continue;
2567                                 }
2568                                 KASSERT((disk->d_flags &
2569                                     G_MIRROR_DISK_FLAG_DIRTY) != 0,
2570                                     ("Disk %s isn't marked as dirty.",
2571                                     g_mirror_get_diskname(disk)));
2572                                 /* Skip the disk with the biggest priority. */
2573                                 if (disk == pdisk)
2574                                         continue;
2575                                 disk->d_sync.ds_syncid = 0;
2576                         }
2577                 } else if (dirty < ndisks) {
2578                         /*
2579                          * Force synchronization for all dirty disks.
2580                          * We have some non-dirty disks.
2581                          */
2582                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2583                                 if (disk->d_sync.ds_syncid != sc->sc_syncid)
2584                                         continue;
2585                                 if ((disk->d_flags &
2586                                     G_MIRROR_DISK_FLAG_SYNCHRONIZING) != 0) {
2587                                         continue;
2588                                 }
2589                                 if ((disk->d_flags &
2590                                     G_MIRROR_DISK_FLAG_DIRTY) == 0) {
2591                                         continue;
2592                                 }
2593                                 disk->d_sync.ds_syncid = 0;
2594                         }
2595                 }
2596
2597                 /* Reset hint. */
2598                 sc->sc_hint = NULL;
2599                 if (force) {
2600                         /* Remember to bump syncid on first write. */
2601                         sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2602                 }
2603                 state = G_MIRROR_DEVICE_STATE_RUNNING;
2604                 G_MIRROR_DEBUG(1, "Device %s state changed from %s to %s.",
2605                     sc->sc_name, g_mirror_device_state2str(sc->sc_state),
2606                     g_mirror_device_state2str(state));
2607                 sc->sc_state = state;
2608                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2609                         state = g_mirror_determine_state(disk);
2610                         g_mirror_event_send(disk, state,
2611                             G_MIRROR_EVENT_DONTWAIT);
2612                         if (state == G_MIRROR_DISK_STATE_STALE)
2613                                 sc->sc_bump_id |= G_MIRROR_BUMP_SYNCID;
2614                 }
2615                 break;
2616             }
2617         case G_MIRROR_DEVICE_STATE_RUNNING:
2618                 if (g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE) == 0 &&
2619                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_NEW) == 0) {
2620                         /*
2621                          * No usable disks, so destroy the device.
2622                          */
2623                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
2624                         break;
2625                 } else if (g_mirror_ndisks(sc,
2626                     G_MIRROR_DISK_STATE_ACTIVE) > 0 &&
2627                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_NEW) == 0) {
2628                         /*
2629                          * We have active disks, launch provider if it doesn't
2630                          * exist.
2631                          */
2632                         if (sc->sc_provider == NULL)
2633                                 g_mirror_launch_provider(sc);
2634                         if (sc->sc_rootmount != NULL) {
2635                                 G_MIRROR_DEBUG(1, "root_mount_rel[%u] %p",
2636                                     __LINE__, sc->sc_rootmount);
2637                                 root_mount_rel(sc->sc_rootmount);
2638                                 sc->sc_rootmount = NULL;
2639                         }
2640                 }
2641                 /*
2642                  * Genid should be bumped immediately, so do it here.
2643                  */
2644                 if ((sc->sc_bump_id & G_MIRROR_BUMP_GENID) != 0) {
2645                         sc->sc_bump_id &= ~G_MIRROR_BUMP_GENID;
2646                         g_mirror_bump_genid(sc);
2647                 }
2648                 if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID_NOW) != 0) {
2649                         sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID_NOW;
2650                         g_mirror_bump_syncid(sc);
2651                 }
2652                 break;
2653         default:
2654                 KASSERT(1 == 0, ("Wrong device state (%s, %s).",
2655                     sc->sc_name, g_mirror_device_state2str(sc->sc_state)));
2656                 break;
2657         }
2658 }
2659
2660 /*
2661  * Update disk state and device state if needed.
2662  */
2663 #define DISK_STATE_CHANGED()    G_MIRROR_DEBUG(1,                       \
2664         "Disk %s state changed from %s to %s (device %s).",             \
2665         g_mirror_get_diskname(disk),                                    \
2666         g_mirror_disk_state2str(disk->d_state),                         \
2667         g_mirror_disk_state2str(state), sc->sc_name)
2668 static int
2669 g_mirror_update_disk(struct g_mirror_disk *disk, u_int state)
2670 {
2671         struct g_mirror_softc *sc;
2672
2673         sc = disk->d_softc;
2674         sx_assert(&sc->sc_lock, SX_XLOCKED);
2675
2676 again:
2677         G_MIRROR_DEBUG(3, "Changing disk %s state from %s to %s.",
2678             g_mirror_get_diskname(disk), g_mirror_disk_state2str(disk->d_state),
2679             g_mirror_disk_state2str(state));
2680         switch (state) {
2681         case G_MIRROR_DISK_STATE_NEW:
2682                 /*
2683                  * Possible scenarios:
2684                  * 1. New disk arrive.
2685                  */
2686                 /* Previous state should be NONE. */
2687                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NONE,
2688                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2689                     g_mirror_disk_state2str(disk->d_state)));
2690                 DISK_STATE_CHANGED();
2691
2692                 disk->d_state = state;
2693                 g_topology_lock();
2694                 if (LIST_EMPTY(&sc->sc_disks))
2695                         LIST_INSERT_HEAD(&sc->sc_disks, disk, d_next);
2696                 else {
2697                         struct g_mirror_disk *dp;
2698
2699                         LIST_FOREACH(dp, &sc->sc_disks, d_next) {
2700                                 if (disk->d_priority >= dp->d_priority) {
2701                                         LIST_INSERT_BEFORE(dp, disk, d_next);
2702                                         dp = NULL;
2703                                         break;
2704                                 }
2705                                 if (LIST_NEXT(dp, d_next) == NULL)
2706                                         break;
2707                         }
2708                         if (dp != NULL)
2709                                 LIST_INSERT_AFTER(dp, disk, d_next);
2710                 }
2711                 g_topology_unlock();
2712                 G_MIRROR_DEBUG(1, "Device %s: provider %s detected.",
2713                     sc->sc_name, g_mirror_get_diskname(disk));
2714                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING)
2715                         break;
2716                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2717                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2718                     g_mirror_device_state2str(sc->sc_state),
2719                     g_mirror_get_diskname(disk),
2720                     g_mirror_disk_state2str(disk->d_state)));
2721                 state = g_mirror_determine_state(disk);
2722                 if (state != G_MIRROR_DISK_STATE_NONE)
2723                         goto again;
2724                 break;
2725         case G_MIRROR_DISK_STATE_ACTIVE:
2726                 /*
2727                  * Possible scenarios:
2728                  * 1. New disk does not need synchronization.
2729                  * 2. Synchronization process finished successfully.
2730                  */
2731                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2732                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2733                     g_mirror_device_state2str(sc->sc_state),
2734                     g_mirror_get_diskname(disk),
2735                     g_mirror_disk_state2str(disk->d_state)));
2736                 /* Previous state should be NEW or SYNCHRONIZING. */
2737                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW ||
2738                     disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2739                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2740                     g_mirror_disk_state2str(disk->d_state)));
2741                 DISK_STATE_CHANGED();
2742
2743                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
2744                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_SYNCHRONIZING;
2745                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_FORCE_SYNC;
2746                         g_mirror_sync_stop(disk, 0);
2747                 }
2748                 disk->d_state = state;
2749                 disk->d_sync.ds_offset = 0;
2750                 disk->d_sync.ds_offset_done = 0;
2751                 g_mirror_update_idle(sc, disk);
2752                 g_mirror_update_metadata(disk);
2753                 G_MIRROR_DEBUG(1, "Device %s: provider %s activated.",
2754                     sc->sc_name, g_mirror_get_diskname(disk));
2755                 break;
2756         case G_MIRROR_DISK_STATE_STALE:
2757                 /*
2758                  * Possible scenarios:
2759                  * 1. Stale disk was connected.
2760                  */
2761                 /* Previous state should be NEW. */
2762                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2763                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2764                     g_mirror_disk_state2str(disk->d_state)));
2765                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2766                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2767                     g_mirror_device_state2str(sc->sc_state),
2768                     g_mirror_get_diskname(disk),
2769                     g_mirror_disk_state2str(disk->d_state)));
2770                 /*
2771                  * STALE state is only possible if device is marked
2772                  * NOAUTOSYNC.
2773                  */
2774                 KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_NOAUTOSYNC) != 0,
2775                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2776                     g_mirror_device_state2str(sc->sc_state),
2777                     g_mirror_get_diskname(disk),
2778                     g_mirror_disk_state2str(disk->d_state)));
2779                 DISK_STATE_CHANGED();
2780
2781                 disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2782                 disk->d_state = state;
2783                 g_mirror_update_metadata(disk);
2784                 G_MIRROR_DEBUG(0, "Device %s: provider %s is stale.",
2785                     sc->sc_name, g_mirror_get_diskname(disk));
2786                 break;
2787         case G_MIRROR_DISK_STATE_SYNCHRONIZING:
2788                 /*
2789                  * Possible scenarios:
2790                  * 1. Disk which needs synchronization was connected.
2791                  */
2792                 /* Previous state should be NEW. */
2793                 KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2794                     ("Wrong disk state (%s, %s).", g_mirror_get_diskname(disk),
2795                     g_mirror_disk_state2str(disk->d_state)));
2796                 KASSERT(sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING,
2797                     ("Wrong device state (%s, %s, %s, %s).", sc->sc_name,
2798                     g_mirror_device_state2str(sc->sc_state),
2799                     g_mirror_get_diskname(disk),
2800                     g_mirror_disk_state2str(disk->d_state)));
2801                 DISK_STATE_CHANGED();
2802
2803                 if (disk->d_state == G_MIRROR_DISK_STATE_NEW)
2804                         disk->d_flags &= ~G_MIRROR_DISK_FLAG_DIRTY;
2805                 disk->d_state = state;
2806                 if (sc->sc_provider != NULL) {
2807                         g_mirror_sync_start(disk);
2808                         g_mirror_update_metadata(disk);
2809                 }
2810                 break;
2811         case G_MIRROR_DISK_STATE_DISCONNECTED:
2812                 /*
2813                  * Possible scenarios:
2814                  * 1. Device wasn't running yet, but disk disappear.
2815                  * 2. Disk was active and disapppear.
2816                  * 3. Disk disappear during synchronization process.
2817                  */
2818                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_RUNNING) {
2819                         /*
2820                          * Previous state should be ACTIVE, STALE or
2821                          * SYNCHRONIZING.
2822                          */
2823                         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_ACTIVE ||
2824                             disk->d_state == G_MIRROR_DISK_STATE_STALE ||
2825                             disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING,
2826                             ("Wrong disk state (%s, %s).",
2827                             g_mirror_get_diskname(disk),
2828                             g_mirror_disk_state2str(disk->d_state)));
2829                 } else if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING) {
2830                         /* Previous state should be NEW. */
2831                         KASSERT(disk->d_state == G_MIRROR_DISK_STATE_NEW,
2832                             ("Wrong disk state (%s, %s).",
2833                             g_mirror_get_diskname(disk),
2834                             g_mirror_disk_state2str(disk->d_state)));
2835                         /*
2836                          * Reset bumping syncid if disk disappeared in STARTING
2837                          * state.
2838                          */
2839                         if ((sc->sc_bump_id & G_MIRROR_BUMP_SYNCID) != 0)
2840                                 sc->sc_bump_id &= ~G_MIRROR_BUMP_SYNCID;
2841 #ifdef  INVARIANTS
2842                 } else {
2843                         KASSERT(1 == 0, ("Wrong device state (%s, %s, %s, %s).",
2844                             sc->sc_name,
2845                             g_mirror_device_state2str(sc->sc_state),
2846                             g_mirror_get_diskname(disk),
2847                             g_mirror_disk_state2str(disk->d_state)));
2848 #endif
2849                 }
2850                 DISK_STATE_CHANGED();
2851                 G_MIRROR_DEBUG(0, "Device %s: provider %s disconnected.",
2852                     sc->sc_name, g_mirror_get_diskname(disk));
2853
2854                 g_mirror_destroy_disk(disk);
2855                 break;
2856         case G_MIRROR_DISK_STATE_DESTROY:
2857             {
2858                 int error;
2859
2860                 error = g_mirror_clear_metadata(disk);
2861                 if (error != 0) {
2862                         G_MIRROR_DEBUG(0,
2863                             "Device %s: failed to clear metadata on %s: %d.",
2864                             sc->sc_name, g_mirror_get_diskname(disk), error);
2865                         break;
2866                 }
2867                 DISK_STATE_CHANGED();
2868                 G_MIRROR_DEBUG(0, "Device %s: provider %s destroyed.",
2869                     sc->sc_name, g_mirror_get_diskname(disk));
2870
2871                 g_mirror_destroy_disk(disk);
2872                 sc->sc_ndisks--;
2873                 LIST_FOREACH(disk, &sc->sc_disks, d_next) {
2874                         g_mirror_update_metadata(disk);
2875                 }
2876                 break;
2877             }
2878         default:
2879                 KASSERT(1 == 0, ("Unknown state (%u).", state));
2880                 break;
2881         }
2882         return (0);
2883 }
2884 #undef  DISK_STATE_CHANGED
2885
2886 int
2887 g_mirror_read_metadata(struct g_consumer *cp, struct g_mirror_metadata *md)
2888 {
2889         struct g_provider *pp;
2890         u_char *buf;
2891         int error;
2892
2893         g_topology_assert();
2894
2895         error = g_access(cp, 1, 0, 0);
2896         if (error != 0)
2897                 return (error);
2898         pp = cp->provider;
2899         g_topology_unlock();
2900         /* Metadata are stored on last sector. */
2901         buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
2902             &error);
2903         g_topology_lock();
2904         g_access(cp, -1, 0, 0);
2905         if (buf == NULL) {
2906                 G_MIRROR_DEBUG(1, "Cannot read metadata from %s (error=%d).",
2907                     cp->provider->name, error);
2908                 return (error);
2909         }
2910
2911         /* Decode metadata. */
2912         error = mirror_metadata_decode(buf, md);
2913         g_free(buf);
2914         if (strcmp(md->md_magic, G_MIRROR_MAGIC) != 0)
2915                 return (EINVAL);
2916         if (md->md_version > G_MIRROR_VERSION) {
2917                 G_MIRROR_DEBUG(0,
2918                     "Kernel module is too old to handle metadata from %s.",
2919                     cp->provider->name);
2920                 return (EINVAL);
2921         }
2922         if (error != 0) {
2923                 G_MIRROR_DEBUG(1, "MD5 metadata hash mismatch for provider %s.",
2924                     cp->provider->name);
2925                 return (error);
2926         }
2927
2928         return (0);
2929 }
2930
2931 static int
2932 g_mirror_check_metadata(struct g_mirror_softc *sc, struct g_provider *pp,
2933     struct g_mirror_metadata *md)
2934 {
2935
2936         G_MIRROR_DEBUG(2, "%s: md_did 0x%u disk %s device %s md_all 0x%x "
2937             "sc_ndisks 0x%x md_slice 0x%x sc_slice 0x%x md_balance 0x%x "
2938             "sc_balance 0x%x sc_mediasize 0x%jx pp_mediasize 0x%jx "
2939             "md_sectorsize 0x%x sc_sectorsize 0x%x md_mflags 0x%jx "
2940             "md_dflags 0x%jx md_syncid 0x%x md_genid 0x%x md_priority 0x%x "
2941             "sc_state 0x%x.",
2942             __func__, md->md_did, pp->name, sc->sc_name, md->md_all,
2943             sc->sc_ndisks, md->md_slice, sc->sc_slice, md->md_balance,
2944             sc->sc_balance, (uintmax_t)sc->sc_mediasize,
2945             (uintmax_t)pp->mediasize, md->md_sectorsize, sc->sc_sectorsize,
2946             (uintmax_t)md->md_mflags, (uintmax_t)md->md_dflags, md->md_syncid,
2947             md->md_genid, md->md_priority, sc->sc_state);
2948
2949         if (g_mirror_id2disk(sc, md->md_did) != NULL) {
2950                 G_MIRROR_DEBUG(1, "Disk %s (id=%u) already exists, skipping.",
2951                     pp->name, md->md_did);
2952                 return (EEXIST);
2953         }
2954         if (sc->sc_mediasize > pp->mediasize) {
2955                 G_MIRROR_DEBUG(1,
2956                     "Invalid size of disk %s (device %s), skipping.", pp->name,
2957                     sc->sc_name);
2958                 return (EINVAL);
2959         }
2960         if (md->md_sectorsize != sc->sc_sectorsize) {
2961                 G_MIRROR_DEBUG(1,
2962                     "Invalid '%s' field on disk %s (device %s), skipping.",
2963                     "md_sectorsize", pp->name, sc->sc_name);
2964                 return (EINVAL);
2965         }
2966         if ((sc->sc_sectorsize % pp->sectorsize) != 0) {
2967                 G_MIRROR_DEBUG(1,
2968                     "Invalid sector size of disk %s (device %s), skipping.",
2969                     pp->name, sc->sc_name);
2970                 return (EINVAL);
2971         }
2972         if ((md->md_mflags & ~G_MIRROR_DEVICE_FLAG_MASK) != 0) {
2973                 G_MIRROR_DEBUG(1,
2974                     "Invalid device flags on disk %s (device %s), skipping.",
2975                     pp->name, sc->sc_name);
2976                 return (EINVAL);
2977         }
2978         if ((md->md_dflags & ~G_MIRROR_DISK_FLAG_MASK) != 0) {
2979                 G_MIRROR_DEBUG(1,
2980                     "Invalid disk flags on disk %s (device %s), skipping.",
2981                     pp->name, sc->sc_name);
2982                 return (EINVAL);
2983         }
2984         return (0);
2985 }
2986
2987 int
2988 g_mirror_add_disk(struct g_mirror_softc *sc, struct g_provider *pp,
2989     struct g_mirror_metadata *md)
2990 {
2991         struct g_mirror_disk *disk;
2992         int error;
2993
2994         g_topology_assert_not();
2995         G_MIRROR_DEBUG(2, "Adding disk %s.", pp->name);
2996
2997         error = g_mirror_check_metadata(sc, pp, md);
2998         if (error != 0)
2999                 return (error);
3000
3001         if (md->md_genid < sc->sc_genid) {
3002                 G_MIRROR_DEBUG(0, "Component %s (device %s) broken, skipping.",
3003                     pp->name, sc->sc_name);
3004                 return (EINVAL);
3005         }
3006
3007         /*
3008          * If the component disk we're tasting has newer metadata than the
3009          * STARTING gmirror device, refresh the device from the component.
3010          */
3011         error = g_mirror_refresh_device(sc, pp, md);
3012         if (error != 0)
3013                 return (error);
3014
3015         disk = g_mirror_init_disk(sc, pp, md, &error);
3016         if (disk == NULL)
3017                 return (error);
3018         error = g_mirror_event_send(disk, G_MIRROR_DISK_STATE_NEW,
3019             G_MIRROR_EVENT_WAIT);
3020         if (error != 0)
3021                 return (error);
3022         if (md->md_version < G_MIRROR_VERSION) {
3023                 G_MIRROR_DEBUG(0, "Upgrading metadata on %s (v%d->v%d).",
3024                     pp->name, md->md_version, G_MIRROR_VERSION);
3025                 g_mirror_update_metadata(disk);
3026         }
3027         return (0);
3028 }
3029
3030 static void
3031 g_mirror_destroy_delayed(void *arg, int flag)
3032 {
3033         struct g_mirror_softc *sc;
3034         int error;
3035
3036         if (flag == EV_CANCEL) {
3037                 G_MIRROR_DEBUG(1, "Destroying canceled.");
3038                 return;
3039         }
3040         sc = arg;
3041         g_topology_unlock();
3042         sx_xlock(&sc->sc_lock);
3043         KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) == 0,
3044             ("DESTROY flag set on %s.", sc->sc_name));
3045         KASSERT((sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0,
3046             ("CLOSEWAIT flag not set on %s.", sc->sc_name));
3047         G_MIRROR_DEBUG(1, "Destroying %s (delayed).", sc->sc_name);
3048         error = g_mirror_destroy(sc, G_MIRROR_DESTROY_SOFT);
3049         if (error != 0) {
3050                 G_MIRROR_DEBUG(0, "Cannot destroy %s (error=%d).",
3051                     sc->sc_name, error);
3052                 sx_xunlock(&sc->sc_lock);
3053         }
3054         g_topology_lock();
3055 }
3056
3057 static int
3058 g_mirror_access(struct g_provider *pp, int acr, int acw, int ace)
3059 {
3060         struct g_mirror_softc *sc;
3061         int error = 0;
3062
3063         g_topology_assert();
3064         G_MIRROR_DEBUG(2, "Access request for %s: r%dw%de%d.", pp->name, acr,
3065             acw, ace);
3066
3067         sc = pp->private;
3068         KASSERT(sc != NULL, ("NULL softc (provider=%s).", pp->name));
3069
3070         g_topology_unlock();
3071         sx_xlock(&sc->sc_lock);
3072         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0 ||
3073             (sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0 ||
3074             LIST_EMPTY(&sc->sc_disks)) {
3075                 if (acr > 0 || acw > 0 || ace > 0)
3076                         error = ENXIO;
3077                 goto end;
3078         }
3079         sc->sc_provider_open += acr + acw + ace;
3080         if (pp->acw + acw == 0)
3081                 g_mirror_idle(sc, 0);
3082         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_CLOSEWAIT) != 0 &&
3083             sc->sc_provider_open == 0)
3084                 g_post_event(g_mirror_destroy_delayed, sc, M_WAITOK, sc, NULL);
3085 end:
3086         sx_xunlock(&sc->sc_lock);
3087         g_topology_lock();
3088         return (error);
3089 }
3090
3091 static void
3092 g_mirror_reinit_from_metadata(struct g_mirror_softc *sc,
3093     const struct g_mirror_metadata *md)
3094 {
3095
3096         sc->sc_genid = md->md_genid;
3097         sc->sc_syncid = md->md_syncid;
3098
3099         sc->sc_slice = md->md_slice;
3100         sc->sc_balance = md->md_balance;
3101         sc->sc_mediasize = md->md_mediasize;
3102         sc->sc_ndisks = md->md_all;
3103         sc->sc_flags &= ~G_MIRROR_DEVICE_FLAG_MASK;
3104         sc->sc_flags |= (md->md_mflags & G_MIRROR_DEVICE_FLAG_MASK);
3105 }
3106
3107 struct g_geom *
3108 g_mirror_create(struct g_class *mp, const struct g_mirror_metadata *md,
3109     u_int type)
3110 {
3111         struct g_mirror_softc *sc;
3112         struct g_geom *gp;
3113         int error, timeout;
3114
3115         g_topology_assert();
3116         G_MIRROR_DEBUG(1, "Creating device %s (id=%u).", md->md_name,
3117             md->md_mid);
3118
3119         /* One disk is minimum. */
3120         if (md->md_all < 1)
3121                 return (NULL);
3122         /*
3123          * Action geom.
3124          */
3125         gp = g_new_geomf(mp, "%s", md->md_name);
3126         sc = malloc(sizeof(*sc), M_MIRROR, M_WAITOK | M_ZERO);
3127         gp->start = g_mirror_start;
3128         gp->orphan = g_mirror_orphan;
3129         gp->access = g_mirror_access;
3130         gp->dumpconf = g_mirror_dumpconf;
3131
3132         sc->sc_type = type;
3133         sc->sc_id = md->md_mid;
3134         g_mirror_reinit_from_metadata(sc, md);
3135         sc->sc_sectorsize = md->md_sectorsize;
3136         sc->sc_bump_id = 0;
3137         sc->sc_idle = 1;
3138         sc->sc_last_write = time_uptime;
3139         sc->sc_writes = 0;
3140         sc->sc_refcnt = 1;
3141         sx_init(&sc->sc_lock, "gmirror:lock");
3142         TAILQ_INIT(&sc->sc_queue);
3143         mtx_init(&sc->sc_queue_mtx, "gmirror:queue", NULL, MTX_DEF);
3144         TAILQ_INIT(&sc->sc_regular_delayed);
3145         TAILQ_INIT(&sc->sc_inflight);
3146         TAILQ_INIT(&sc->sc_sync_delayed);
3147         LIST_INIT(&sc->sc_disks);
3148         TAILQ_INIT(&sc->sc_events);
3149         mtx_init(&sc->sc_events_mtx, "gmirror:events", NULL, MTX_DEF);
3150         callout_init(&sc->sc_callout, 1);
3151         mtx_init(&sc->sc_done_mtx, "gmirror:done", NULL, MTX_DEF);
3152         sc->sc_state = G_MIRROR_DEVICE_STATE_STARTING;
3153         gp->softc = sc;
3154         sc->sc_geom = gp;
3155         sc->sc_provider = NULL;
3156         sc->sc_provider_open = 0;
3157         /*
3158          * Synchronization geom.
3159          */
3160         gp = g_new_geomf(mp, "%s.sync", md->md_name);
3161         gp->softc = sc;
3162         gp->orphan = g_mirror_orphan;
3163         sc->sc_sync.ds_geom = gp;
3164         sc->sc_sync.ds_ndisks = 0;
3165         error = kproc_create(g_mirror_worker, sc, &sc->sc_worker, 0, 0,
3166             "g_mirror %s", md->md_name);
3167         if (error != 0) {
3168                 G_MIRROR_DEBUG(1, "Cannot create kernel thread for %s.",
3169                     sc->sc_name);
3170                 g_destroy_geom(sc->sc_sync.ds_geom);
3171                 g_destroy_geom(sc->sc_geom);
3172                 g_mirror_free_device(sc);
3173                 return (NULL);
3174         }
3175
3176         G_MIRROR_DEBUG(1, "Device %s created (%u components, id=%u).",
3177             sc->sc_name, sc->sc_ndisks, sc->sc_id);
3178
3179         sc->sc_rootmount = root_mount_hold("GMIRROR");
3180         G_MIRROR_DEBUG(1, "root_mount_hold %p", sc->sc_rootmount);
3181
3182         /*
3183          * Schedule startup timeout.
3184          */
3185         timeout = g_mirror_timeout * hz;
3186         sc->sc_timeout_event = malloc(sizeof(struct g_mirror_event), M_MIRROR,
3187             M_WAITOK);
3188         callout_reset(&sc->sc_callout, timeout, g_mirror_go, sc);
3189         return (sc->sc_geom);
3190 }
3191
3192 int
3193 g_mirror_destroy(struct g_mirror_softc *sc, int how)
3194 {
3195         struct g_mirror_disk *disk;
3196
3197         g_topology_assert_not();
3198         sx_assert(&sc->sc_lock, SX_XLOCKED);
3199
3200         if (sc->sc_provider_open != 0) {
3201                 switch (how) {
3202                 case G_MIRROR_DESTROY_SOFT:
3203                         G_MIRROR_DEBUG(1,
3204                             "Device %s is still open (%d).", sc->sc_name,
3205                             sc->sc_provider_open);
3206                         return (EBUSY);
3207                 case G_MIRROR_DESTROY_DELAYED:
3208                         G_MIRROR_DEBUG(1,
3209                             "Device %s will be destroyed on last close.",
3210                             sc->sc_name);
3211                         LIST_FOREACH(disk, &sc->sc_disks, d_next) {
3212                                 if (disk->d_state ==
3213                                     G_MIRROR_DISK_STATE_SYNCHRONIZING) {
3214                                         g_mirror_sync_stop(disk, 1);
3215                                 }
3216                         }
3217                         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_CLOSEWAIT;
3218                         return (EBUSY);
3219                 case G_MIRROR_DESTROY_HARD:
3220                         G_MIRROR_DEBUG(1, "Device %s is still open, so it "
3221                             "can't be definitely removed.", sc->sc_name);
3222                 }
3223         }
3224
3225         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
3226                 sx_xunlock(&sc->sc_lock);
3227                 return (0);
3228         }
3229         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DESTROY;
3230         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_DRAIN;
3231         G_MIRROR_DEBUG(4, "%s: Waking up %p.", __func__, sc);
3232         sx_xunlock(&sc->sc_lock);
3233         mtx_lock(&sc->sc_queue_mtx);
3234         wakeup(sc);
3235         mtx_unlock(&sc->sc_queue_mtx);
3236         G_MIRROR_DEBUG(4, "%s: Sleeping %p.", __func__, &sc->sc_worker);
3237         while (sc->sc_worker != NULL)
3238                 tsleep(&sc->sc_worker, PRIBIO, "m:destroy", hz / 5);
3239         G_MIRROR_DEBUG(4, "%s: Woken up %p.", __func__, &sc->sc_worker);
3240         sx_xlock(&sc->sc_lock);
3241         g_mirror_destroy_device(sc);
3242         return (0);
3243 }
3244
3245 static void
3246 g_mirror_taste_orphan(struct g_consumer *cp)
3247 {
3248
3249         KASSERT(1 == 0, ("%s called while tasting %s.", __func__,
3250             cp->provider->name));
3251 }
3252
3253 static struct g_geom *
3254 g_mirror_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
3255 {
3256         struct g_mirror_metadata md;
3257         struct g_mirror_softc *sc;
3258         struct g_consumer *cp;
3259         struct g_geom *gp;
3260         int error;
3261
3262         g_topology_assert();
3263         g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
3264         G_MIRROR_DEBUG(2, "Tasting %s.", pp->name);
3265
3266         gp = g_new_geomf(mp, "mirror:taste");
3267         /*
3268          * This orphan function should be never called.
3269          */
3270         gp->orphan = g_mirror_taste_orphan;
3271         cp = g_new_consumer(gp);
3272         error = g_attach(cp, pp);
3273         if (error == 0) {
3274                 error = g_mirror_read_metadata(cp, &md);
3275                 g_detach(cp);
3276         }
3277         g_destroy_consumer(cp);
3278         g_destroy_geom(gp);
3279         if (error != 0)
3280                 return (NULL);
3281         gp = NULL;
3282
3283         if (md.md_provider[0] != '\0' &&
3284             !g_compare_names(md.md_provider, pp->name))
3285                 return (NULL);
3286         if (md.md_provsize != 0 && md.md_provsize != pp->mediasize)
3287                 return (NULL);
3288         if ((md.md_dflags & G_MIRROR_DISK_FLAG_INACTIVE) != 0) {
3289                 G_MIRROR_DEBUG(0,
3290                     "Device %s: provider %s marked as inactive, skipping.",
3291                     md.md_name, pp->name);
3292                 return (NULL);
3293         }
3294         if (g_mirror_debug >= 2)
3295                 mirror_metadata_dump(&md);
3296
3297         /*
3298          * Let's check if device already exists.
3299          */
3300         sc = NULL;
3301         LIST_FOREACH(gp, &mp->geom, geom) {
3302                 sc = gp->softc;
3303                 if (sc == NULL)
3304                         continue;
3305                 if (sc->sc_type != G_MIRROR_TYPE_AUTOMATIC)
3306                         continue;
3307                 if (sc->sc_sync.ds_geom == gp)
3308                         continue;
3309                 if (strcmp(md.md_name, sc->sc_name) != 0)
3310                         continue;
3311                 if (md.md_mid != sc->sc_id) {
3312                         G_MIRROR_DEBUG(0, "Device %s already configured.",
3313                             sc->sc_name);
3314                         return (NULL);
3315                 }
3316                 break;
3317         }
3318         if (gp == NULL) {
3319                 gp = g_mirror_create(mp, &md, G_MIRROR_TYPE_AUTOMATIC);
3320                 if (gp == NULL) {
3321                         G_MIRROR_DEBUG(0, "Cannot create device %s.",
3322                             md.md_name);
3323                         return (NULL);
3324                 }
3325                 sc = gp->softc;
3326         }
3327         G_MIRROR_DEBUG(1, "Adding disk %s to %s.", pp->name, gp->name);
3328         g_topology_unlock();
3329         sx_xlock(&sc->sc_lock);
3330         sc->sc_flags |= G_MIRROR_DEVICE_FLAG_TASTING;
3331         error = g_mirror_add_disk(sc, pp, &md);
3332         sc->sc_flags &= ~G_MIRROR_DEVICE_FLAG_TASTING;
3333         if (error != 0) {
3334                 G_MIRROR_DEBUG(0, "Cannot add disk %s to %s (error=%d).",
3335                     pp->name, gp->name, error);
3336                 if (LIST_EMPTY(&sc->sc_disks)) {
3337                         g_cancel_event(sc);
3338                         g_mirror_destroy(sc, G_MIRROR_DESTROY_HARD);
3339                         g_topology_lock();
3340                         return (NULL);
3341                 }
3342                 gp = NULL;
3343         }
3344         if ((sc->sc_flags & G_MIRROR_DEVICE_FLAG_DESTROY) != 0) {
3345                 g_mirror_destroy(sc, G_MIRROR_DESTROY_HARD);
3346                 g_topology_lock();
3347                 return (NULL);
3348         }
3349         sx_xunlock(&sc->sc_lock);
3350         g_topology_lock();
3351         return (gp);
3352 }
3353
3354 static void
3355 g_mirror_resize(struct g_consumer *cp)
3356 {
3357         struct g_mirror_disk *disk;
3358
3359         g_topology_assert();
3360         g_trace(G_T_TOPOLOGY, "%s(%s)", __func__, cp->provider->name);
3361
3362         disk = cp->private;
3363         if (disk == NULL)
3364                 return;
3365         g_topology_unlock();
3366         g_mirror_update_metadata(disk);
3367         g_topology_lock();
3368 }
3369
3370 static int
3371 g_mirror_destroy_geom(struct gctl_req *req __unused,
3372     struct g_class *mp __unused, struct g_geom *gp)
3373 {
3374         struct g_mirror_softc *sc;
3375         int error;
3376
3377         g_topology_unlock();
3378         sc = gp->softc;
3379         sx_xlock(&sc->sc_lock);
3380         g_cancel_event(sc);
3381         error = g_mirror_destroy(gp->softc, G_MIRROR_DESTROY_SOFT);
3382         if (error != 0)
3383                 sx_xunlock(&sc->sc_lock);
3384         g_topology_lock();
3385         return (error);
3386 }
3387
3388 static void
3389 g_mirror_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
3390     struct g_consumer *cp, struct g_provider *pp)
3391 {
3392         struct g_mirror_softc *sc;
3393
3394         g_topology_assert();
3395
3396         sc = gp->softc;
3397         if (sc == NULL)
3398                 return;
3399         /* Skip synchronization geom. */
3400         if (gp == sc->sc_sync.ds_geom)
3401                 return;
3402         if (pp != NULL) {
3403                 /* Nothing here. */
3404         } else if (cp != NULL) {
3405                 struct g_mirror_disk *disk;
3406
3407                 disk = cp->private;
3408                 if (disk == NULL)
3409                         return;
3410                 sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)disk->d_id);
3411                 if (disk->d_state == G_MIRROR_DISK_STATE_SYNCHRONIZING) {
3412                         sbuf_printf(sb, "%s<Synchronized>", indent);
3413                         if (disk->d_sync.ds_offset == 0)
3414                                 sbuf_cat(sb, "0%");
3415                         else
3416                                 sbuf_printf(sb, "%u%%",
3417                                     (u_int)((disk->d_sync.ds_offset * 100) /
3418                                     sc->sc_mediasize));
3419                         sbuf_cat(sb, "</Synchronized>\n");
3420                         if (disk->d_sync.ds_offset > 0)
3421                                 sbuf_printf(sb, "%s<BytesSynced>%jd"
3422                                     "</BytesSynced>\n", indent,
3423                                     (intmax_t)disk->d_sync.ds_offset);
3424                 }
3425                 sbuf_printf(sb, "%s<SyncID>%u</SyncID>\n", indent,
3426                     disk->d_sync.ds_syncid);
3427                 sbuf_printf(sb, "%s<GenID>%u</GenID>\n", indent,
3428                     disk->d_genid);
3429                 sbuf_printf(sb, "%s<Flags>", indent);
3430                 if (disk->d_flags == 0)
3431                         sbuf_cat(sb, "NONE");
3432                 else {
3433                         int first = 1;
3434
3435 #define ADD_FLAG(flag, name)    do {                                    \
3436         if ((disk->d_flags & (flag)) != 0) {                            \
3437                 if (!first)                                             \
3438                         sbuf_cat(sb, ", ");                             \
3439                 else                                                    \
3440                         first = 0;                                      \
3441                 sbuf_cat(sb, name);                                     \
3442         }                                                               \
3443 } while (0)
3444                         ADD_FLAG(G_MIRROR_DISK_FLAG_DIRTY, "DIRTY");
3445                         ADD_FLAG(G_MIRROR_DISK_FLAG_HARDCODED, "HARDCODED");
3446                         ADD_FLAG(G_MIRROR_DISK_FLAG_INACTIVE, "INACTIVE");
3447                         ADD_FLAG(G_MIRROR_DISK_FLAG_SYNCHRONIZING,
3448                             "SYNCHRONIZING");
3449                         ADD_FLAG(G_MIRROR_DISK_FLAG_FORCE_SYNC, "FORCE_SYNC");
3450                         ADD_FLAG(G_MIRROR_DISK_FLAG_BROKEN, "BROKEN");
3451 #undef  ADD_FLAG
3452                 }
3453                 sbuf_cat(sb, "</Flags>\n");
3454                 sbuf_printf(sb, "%s<Priority>%u</Priority>\n", indent,
3455                     disk->d_priority);
3456                 sbuf_printf(sb, "%s<State>%s</State>\n", indent,
3457                     g_mirror_disk_state2str(disk->d_state));
3458         } else {
3459                 sbuf_printf(sb, "%s<Type>", indent);
3460                 switch (sc->sc_type) {
3461                 case G_MIRROR_TYPE_AUTOMATIC:
3462                         sbuf_cat(sb, "AUTOMATIC");
3463                         break;
3464                 case G_MIRROR_TYPE_MANUAL:
3465                         sbuf_cat(sb, "MANUAL");
3466                         break;
3467                 default:
3468                         sbuf_cat(sb, "UNKNOWN");
3469                         break;
3470                 }
3471                 sbuf_cat(sb, "</Type>\n");
3472                 sbuf_printf(sb, "%s<ID>%u</ID>\n", indent, (u_int)sc->sc_id);
3473                 sbuf_printf(sb, "%s<SyncID>%u</SyncID>\n", indent, sc->sc_syncid);
3474                 sbuf_printf(sb, "%s<GenID>%u</GenID>\n", indent, sc->sc_genid);
3475                 sbuf_printf(sb, "%s<Flags>", indent);
3476                 if (sc->sc_flags == 0)
3477                         sbuf_cat(sb, "NONE");
3478                 else {
3479                         int first = 1;
3480
3481 #define ADD_FLAG(flag, name)    do {                                    \
3482         if ((sc->sc_flags & (flag)) != 0) {                             \
3483                 if (!first)                                             \
3484                         sbuf_cat(sb, ", ");                             \
3485                 else                                                    \
3486                         first = 0;                                      \
3487                 sbuf_cat(sb, name);                                     \
3488         }                                                               \
3489 } while (0)
3490                         ADD_FLAG(G_MIRROR_DEVICE_FLAG_NOFAILSYNC, "NOFAILSYNC");
3491                         ADD_FLAG(G_MIRROR_DEVICE_FLAG_NOAUTOSYNC, "NOAUTOSYNC");
3492 #undef  ADD_FLAG
3493                 }
3494                 sbuf_cat(sb, "</Flags>\n");
3495                 sbuf_printf(sb, "%s<Slice>%u</Slice>\n", indent,
3496                     (u_int)sc->sc_slice);
3497                 sbuf_printf(sb, "%s<Balance>%s</Balance>\n", indent,
3498                     balance_name(sc->sc_balance));
3499                 sbuf_printf(sb, "%s<Components>%u</Components>\n", indent,
3500                     sc->sc_ndisks);
3501                 sbuf_printf(sb, "%s<State>", indent);
3502                 if (sc->sc_state == G_MIRROR_DEVICE_STATE_STARTING)
3503                         sbuf_printf(sb, "%s", "STARTING");
3504                 else if (sc->sc_ndisks ==
3505                     g_mirror_ndisks(sc, G_MIRROR_DISK_STATE_ACTIVE))
3506                         sbuf_printf(sb, "%s", "COMPLETE");
3507                 else
3508                         sbuf_printf(sb, "%s", "DEGRADED");
3509                 sbuf_cat(sb, "</State>\n");
3510         }
3511 }
3512
3513 static void
3514 g_mirror_shutdown_post_sync(void *arg, int howto)
3515 {
3516         struct g_class *mp;
3517         struct g_geom *gp, *gp2;
3518         struct g_mirror_softc *sc;
3519         int error;
3520
3521         if (KERNEL_PANICKED())
3522                 return;
3523
3524         mp = arg;
3525         g_topology_lock();
3526         g_mirror_shutdown = 1;
3527         LIST_FOREACH_SAFE(gp, &mp->geom, geom, gp2) {
3528                 if ((sc = gp->softc) == NULL)
3529                         continue;
3530                 /* Skip synchronization geom. */
3531                 if (gp == sc->sc_sync.ds_geom)
3532                         continue;
3533                 g_topology_unlock();
3534                 sx_xlock(&sc->sc_lock);
3535                 g_mirror_idle(sc, -1);
3536                 g_cancel_event(sc);
3537                 error = g_mirror_destroy(sc, G_MIRROR_DESTROY_DELAYED);
3538                 if (error != 0)
3539                         sx_xunlock(&sc->sc_lock);
3540                 g_topology_lock();
3541         }
3542         g_topology_unlock();
3543 }
3544
3545 static void
3546 g_mirror_init(struct g_class *mp)
3547 {
3548
3549         g_mirror_post_sync = EVENTHANDLER_REGISTER(shutdown_post_sync,
3550             g_mirror_shutdown_post_sync, mp, SHUTDOWN_PRI_FIRST);
3551         if (g_mirror_post_sync == NULL)
3552                 G_MIRROR_DEBUG(0, "Warning! Cannot register shutdown event.");
3553 }
3554
3555 static void
3556 g_mirror_fini(struct g_class *mp)
3557 {
3558
3559         if (g_mirror_post_sync != NULL)
3560                 EVENTHANDLER_DEREGISTER(shutdown_post_sync, g_mirror_post_sync);
3561 }
3562
3563 /*
3564  * Refresh the mirror device's metadata when gmirror encounters a newer
3565  * generation as the individual components are being added to the mirror set.
3566  */
3567 static int
3568 g_mirror_refresh_device(struct g_mirror_softc *sc, const struct g_provider *pp,
3569     const struct g_mirror_metadata *md)
3570 {
3571
3572         g_topology_assert_not();
3573         sx_assert(&sc->sc_lock, SX_XLOCKED);
3574
3575         KASSERT(sc->sc_genid <= md->md_genid,
3576             ("%s: attempted to refresh from stale component %s (device %s) "
3577             "(%u < %u).", __func__, pp->name, sc->sc_name, md->md_genid,
3578             sc->sc_genid));
3579
3580         if (sc->sc_genid > md->md_genid || (sc->sc_genid == md->md_genid &&
3581             sc->sc_syncid >= md->md_syncid))
3582                 return (0);
3583
3584         G_MIRROR_DEBUG(0, "Found newer version for device %s (genid: curr=%u "
3585             "new=%u; syncid: curr=%u new=%u; ndisks: curr=%u new=%u; "
3586             "provider=%s).", sc->sc_name, sc->sc_genid, md->md_genid,
3587             sc->sc_syncid, md->md_syncid, sc->sc_ndisks, md->md_all, pp->name);
3588
3589         if (sc->sc_state != G_MIRROR_DEVICE_STATE_STARTING) {
3590                 /* Probable data corruption detected */
3591                 G_MIRROR_DEBUG(0, "Cannot refresh metadata in %s state "
3592                     "(device=%s genid=%u). A stale mirror device was launched.",
3593                     g_mirror_device_state2str(sc->sc_state), sc->sc_name,
3594                     sc->sc_genid);
3595                 return (EINVAL);
3596         }
3597
3598         /* Update softc */
3599         g_mirror_reinit_from_metadata(sc, md);
3600
3601         G_MIRROR_DEBUG(1, "Refresh device %s (id=%u, state=%s) from disk %s "
3602             "(genid=%u syncid=%u md_all=%u).", sc->sc_name, md->md_mid,
3603             g_mirror_device_state2str(sc->sc_state), pp->name, md->md_genid,
3604             md->md_syncid, (unsigned)md->md_all);
3605
3606         return (0);
3607 }
3608
3609 DECLARE_GEOM_CLASS(g_mirror_class, g_mirror);
3610 MODULE_VERSION(geom_mirror, 0);