sys/geom/raid/tr_raid1.c

   1 /*-
   2  * Copyright (c) 2010 Alexander Motin <mav@FreeBSD.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD$");
  29
  30 #include <sys/param.h>
  31 #include <sys/bio.h>
  32 #include <sys/endian.h>
  33 #include <sys/kernel.h>
  34 #include <sys/kobj.h>
  35 #include <sys/limits.h>
  36 #include <sys/lock.h>
  37 #include <sys/malloc.h>
  38 #include <sys/mutex.h>
  39 #include <sys/sysctl.h>
  40 #include <sys/systm.h>
  41 #include <geom/geom.h>
  42 #include "geom/raid/g_raid.h"
  43 #include "g_raid_tr_if.h"
  44
  45 SYSCTL_DECL(_kern_geom_raid_raid1);
  46
  47 #define RAID1_REBUILD_SLAB      (1 << 20) /* One transation in a rebuild */
  48 static int g_raid1_rebuild_slab = RAID1_REBUILD_SLAB;
  49 TUNABLE_INT("kern.geom.raid.raid1.rebuild_slab_size",
  50     &g_raid1_rebuild_slab);
  51 SYSCTL_UINT(_kern_geom_raid_raid1, OID_AUTO, rebuild_slab_size, CTLFLAG_RW,
  52     &g_raid1_rebuild_slab, 0,
  53     "Amount of the disk to rebuild each read/write cycle of the rebuild.");
  54
  55 #define RAID1_REBUILD_FAIR_IO 20 /* use 1/x of the available I/O */
  56 static int g_raid1_rebuild_fair_io = RAID1_REBUILD_FAIR_IO;
  57 TUNABLE_INT("kern.geom.raid.raid1.rebuild_fair_io",
  58     &g_raid1_rebuild_fair_io);
  59 SYSCTL_UINT(_kern_geom_raid_raid1, OID_AUTO, rebuild_fair_io, CTLFLAG_RW,
  60     &g_raid1_rebuild_fair_io, 0,
  61     "Fraction of the I/O bandwidth to use when disk busy for rebuild.");
  62
  63 #define RAID1_REBUILD_CLUSTER_IDLE 100
  64 static int g_raid1_rebuild_cluster_idle = RAID1_REBUILD_CLUSTER_IDLE;
  65 TUNABLE_INT("kern.geom.raid.raid1.rebuild_cluster_idle",
  66     &g_raid1_rebuild_cluster_idle);
  67 SYSCTL_UINT(_kern_geom_raid_raid1, OID_AUTO, rebuild_cluster_idle, CTLFLAG_RW,
  68     &g_raid1_rebuild_cluster_idle, 0,
  69     "Number of slabs to do each time we trigger a rebuild cycle");
  70
  71 #define RAID1_REBUILD_META_UPDATE 1024 /* update meta data every 1GB or so */
  72 static int g_raid1_rebuild_meta_update = RAID1_REBUILD_META_UPDATE;
  73 TUNABLE_INT("kern.geom.raid.raid1.rebuild_meta_update",
  74     &g_raid1_rebuild_meta_update);
  75 SYSCTL_UINT(_kern_geom_raid_raid1, OID_AUTO, rebuild_meta_update, CTLFLAG_RW,
  76     &g_raid1_rebuild_meta_update, 0,
  77     "When to update the meta data.");
  78
  79 static MALLOC_DEFINE(M_TR_RAID1, "tr_raid1_data", "GEOM_RAID RAID1 data");
  80
  81 #define TR_RAID1_NONE 0
  82 #define TR_RAID1_REBUILD 1
  83 #define TR_RAID1_RESYNC 2
  84
  85 #define TR_RAID1_F_DOING_SOME   0x1
  86 #define TR_RAID1_F_LOCKED       0x2
  87 #define TR_RAID1_F_ABORT        0x4
  88
  89 struct g_raid_tr_raid1_object {
  90         struct g_raid_tr_object  trso_base;
  91         int                      trso_starting;
  92         int                      trso_stopping;
  93         int                      trso_type;
  94         int                      trso_recover_slabs; /* slabs before rest */
  95         int                      trso_fair_io;
  96         int                      trso_meta_update;
  97         int                      trso_flags;
  98         struct g_raid_subdisk   *trso_failed_sd; /* like per volume */
  99         void                    *trso_buffer;    /* Buffer space */
 100         struct bio               trso_bio;
 101 };
 102
 103 static g_raid_tr_taste_t g_raid_tr_taste_raid1;
 104 static g_raid_tr_event_t g_raid_tr_event_raid1;
 105 static g_raid_tr_start_t g_raid_tr_start_raid1;
 106 static g_raid_tr_stop_t g_raid_tr_stop_raid1;
 107 static g_raid_tr_iostart_t g_raid_tr_iostart_raid1;
 108 static g_raid_tr_iodone_t g_raid_tr_iodone_raid1;
 109 static g_raid_tr_kerneldump_t g_raid_tr_kerneldump_raid1;
 110 static g_raid_tr_locked_t g_raid_tr_locked_raid1;
 111 static g_raid_tr_idle_t g_raid_tr_idle_raid1;
 112 static g_raid_tr_free_t g_raid_tr_free_raid1;
 113
 114 static kobj_method_t g_raid_tr_raid1_methods[] = {
 115         KOBJMETHOD(g_raid_tr_taste,     g_raid_tr_taste_raid1),
 116         KOBJMETHOD(g_raid_tr_event,     g_raid_tr_event_raid1),
 117         KOBJMETHOD(g_raid_tr_start,     g_raid_tr_start_raid1),
 118         KOBJMETHOD(g_raid_tr_stop,      g_raid_tr_stop_raid1),
 119         KOBJMETHOD(g_raid_tr_iostart,   g_raid_tr_iostart_raid1),
 120         KOBJMETHOD(g_raid_tr_iodone,    g_raid_tr_iodone_raid1),
 121         KOBJMETHOD(g_raid_tr_kerneldump, g_raid_tr_kerneldump_raid1),
 122         KOBJMETHOD(g_raid_tr_locked,    g_raid_tr_locked_raid1),
 123         KOBJMETHOD(g_raid_tr_idle,      g_raid_tr_idle_raid1),
 124         KOBJMETHOD(g_raid_tr_free,      g_raid_tr_free_raid1),
 125         { 0, 0 }
 126 };
 127
 128 static struct g_raid_tr_class g_raid_tr_raid1_class = {
 129         "RAID1",
 130         g_raid_tr_raid1_methods,
 131         sizeof(struct g_raid_tr_raid1_object),
 132         .trc_enable = 1,
 133         .trc_priority = 100
 134 };
 135
 136 static void g_raid_tr_raid1_rebuild_abort(struct g_raid_tr_object *tr);
 137 static void g_raid_tr_raid1_maybe_rebuild(struct g_raid_tr_object *tr,
 138     struct g_raid_subdisk *sd);
 139
 140 static int
 141 g_raid_tr_taste_raid1(struct g_raid_tr_object *tr, struct g_raid_volume *vol)
 142 {
 143         struct g_raid_tr_raid1_object *trs;
 144
 145         trs = (struct g_raid_tr_raid1_object *)tr;
 146         if (tr->tro_volume->v_raid_level != G_RAID_VOLUME_RL_RAID1 ||
 147             (tr->tro_volume->v_raid_level_qualifier != G_RAID_VOLUME_RLQ_R1SM &&
 148              tr->tro_volume->v_raid_level_qualifier != G_RAID_VOLUME_RLQ_R1MM))
 149                 return (G_RAID_TR_TASTE_FAIL);
 150         trs->trso_starting = 1;
 151         return (G_RAID_TR_TASTE_SUCCEED);
 152 }
 153
 154 static int
 155 g_raid_tr_update_state_raid1(struct g_raid_volume *vol,
 156     struct g_raid_subdisk *sd)
 157 {
 158         struct g_raid_tr_raid1_object *trs;
 159         struct g_raid_softc *sc;
 160         struct g_raid_subdisk *tsd, *bestsd;
 161         u_int s;
 162         int i, na, ns;
 163
 164         sc = vol->v_softc;
 165         trs = (struct g_raid_tr_raid1_object *)vol->v_tr;
 166         if (trs->trso_stopping &&
 167             (trs->trso_flags & TR_RAID1_F_DOING_SOME) == 0)
 168                 s = G_RAID_VOLUME_S_STOPPED;
 169         else if (trs->trso_starting)
 170                 s = G_RAID_VOLUME_S_STARTING;
 171         else {
 172                 /* Make sure we have at least one ACTIVE disk. */
 173                 na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
 174                 if (na == 0) {
 175                         /*
 176                          * Critical situation! We have no any active disk!
 177                          * Choose the best disk we have to make it active.
 178                          */
 179                         bestsd = &vol->v_subdisks[0];
 180                         for (i = 1; i < vol->v_disks_count; i++) {
 181                                 tsd = &vol->v_subdisks[i];
 182                                 if (tsd->sd_state > bestsd->sd_state)
 183                                         bestsd = tsd;
 184                                 else if (tsd->sd_state == bestsd->sd_state &&
 185                                     (tsd->sd_state == G_RAID_SUBDISK_S_REBUILD ||
 186                                      tsd->sd_state == G_RAID_SUBDISK_S_RESYNC) &&
 187                                     tsd->sd_rebuild_pos > bestsd->sd_rebuild_pos)
 188                                         bestsd = tsd;
 189                         }
 190                         if (bestsd->sd_state >= G_RAID_SUBDISK_S_UNINITIALIZED) {
 191                                 /* We found reasonable candidate. */
 192                                 G_RAID_DEBUG1(1, sc,
 193                                     "Promote subdisk %s:%d from %s to ACTIVE.",
 194                                     vol->v_name, bestsd->sd_pos,
 195                                     g_raid_subdisk_state2str(bestsd->sd_state));
 196                                 g_raid_change_subdisk_state(bestsd,
 197                                     G_RAID_SUBDISK_S_ACTIVE);
 198                                 g_raid_write_metadata(sc,
 199                                     vol, bestsd, bestsd->sd_disk);
 200                         }
 201                 }
 202                 na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
 203                 ns = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
 204                      g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
 205                 if (na == vol->v_disks_count)
 206                         s = G_RAID_VOLUME_S_OPTIMAL;
 207                 else if (na + ns == vol->v_disks_count)
 208                         s = G_RAID_VOLUME_S_SUBOPTIMAL;
 209                 else if (na > 0)
 210                         s = G_RAID_VOLUME_S_DEGRADED;
 211                 else
 212                         s = G_RAID_VOLUME_S_BROKEN;
 213                 g_raid_tr_raid1_maybe_rebuild(vol->v_tr, sd);
 214         }
 215         if (s != vol->v_state) {
 216                 g_raid_event_send(vol, G_RAID_VOLUME_S_ALIVE(s) ?
 217                     G_RAID_VOLUME_E_UP : G_RAID_VOLUME_E_DOWN,
 218                     G_RAID_EVENT_VOLUME);
 219                 g_raid_change_volume_state(vol, s);
 220                 if (!trs->trso_starting && !trs->trso_stopping)
 221                         g_raid_write_metadata(sc, vol, NULL, NULL);
 222         }
 223         return (0);
 224 }
 225
 226 static void
 227 g_raid_tr_raid1_fail_disk(struct g_raid_softc *sc, struct g_raid_subdisk *sd,
 228     struct g_raid_disk *disk)
 229 {
 230         /*
 231          * We don't fail the last disk in the pack, since it still has decent
 232          * data on it and that's better than failing the disk if it is the root
 233          * file system.
 234          *
 235          * XXX should this be controlled via a tunable?  It makes sense for
 236          * the volume that has / on it.  I can't think of a case where we'd
 237          * want the volume to go away on this kind of event.
 238          */
 239         if (g_raid_nsubdisks(sd->sd_volume, G_RAID_SUBDISK_S_ACTIVE) == 1 &&
 240             g_raid_get_subdisk(sd->sd_volume, G_RAID_SUBDISK_S_ACTIVE) == sd)
 241                 return;
 242         g_raid_fail_disk(sc, sd, disk);
 243 }
 244
 245 static void
 246 g_raid_tr_raid1_rebuild_some(struct g_raid_tr_object *tr)
 247 {
 248         struct g_raid_tr_raid1_object *trs;
 249         struct g_raid_subdisk *sd, *good_sd;
 250         struct bio *bp;
 251
 252         trs = (struct g_raid_tr_raid1_object *)tr;
 253         if (trs->trso_flags & TR_RAID1_F_DOING_SOME)
 254                 return;
 255         sd = trs->trso_failed_sd;
 256         good_sd = g_raid_get_subdisk(sd->sd_volume, G_RAID_SUBDISK_S_ACTIVE);
 257         if (good_sd == NULL) {
 258                 g_raid_tr_raid1_rebuild_abort(tr);
 259                 return;
 260         }
 261         bp = &trs->trso_bio;
 262         memset(bp, 0, sizeof(*bp));
 263         bp->bio_offset = sd->sd_rebuild_pos;
 264         bp->bio_length = MIN(g_raid1_rebuild_slab,
 265             sd->sd_size - sd->sd_rebuild_pos);
 266         bp->bio_data = trs->trso_buffer;
 267         bp->bio_cmd = BIO_READ;
 268         bp->bio_cflags = G_RAID_BIO_FLAG_SYNC;
 269         bp->bio_caller1 = good_sd;
 270         trs->trso_flags |= TR_RAID1_F_DOING_SOME;
 271         trs->trso_flags |= TR_RAID1_F_LOCKED;
 272         g_raid_lock_range(sd->sd_volume,        /* Lock callback starts I/O */
 273            bp->bio_offset, bp->bio_length, NULL, bp);
 274 }
 275
 276 static void
 277 g_raid_tr_raid1_rebuild_done(struct g_raid_tr_raid1_object *trs)
 278 {
 279         struct g_raid_volume *vol;
 280         struct g_raid_subdisk *sd;
 281
 282         vol = trs->trso_base.tro_volume;
 283         sd = trs->trso_failed_sd;
 284         g_raid_write_metadata(vol->v_softc, vol, sd, sd->sd_disk);
 285         free(trs->trso_buffer, M_TR_RAID1);
 286         trs->trso_buffer = NULL;
 287         trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
 288         trs->trso_type = TR_RAID1_NONE;
 289         trs->trso_recover_slabs = 0;
 290         trs->trso_failed_sd = NULL;
 291         g_raid_tr_update_state_raid1(vol, NULL);
 292 }
 293
 294 static void
 295 g_raid_tr_raid1_rebuild_finish(struct g_raid_tr_object *tr)
 296 {
 297         struct g_raid_tr_raid1_object *trs;
 298         struct g_raid_subdisk *sd;
 299
 300         trs = (struct g_raid_tr_raid1_object *)tr;
 301         sd = trs->trso_failed_sd;
 302         G_RAID_DEBUG1(0, tr->tro_volume->v_softc,
 303             "Subdisk %s:%d-%s rebuild completed.",
 304             sd->sd_volume->v_name, sd->sd_pos,
 305             sd->sd_disk ? g_raid_get_diskname(sd->sd_disk) : "[none]");
 306         g_raid_change_subdisk_state(sd, G_RAID_SUBDISK_S_ACTIVE);
 307         sd->sd_rebuild_pos = 0;
 308         g_raid_tr_raid1_rebuild_done(trs);
 309 }
 310
 311 static void
 312 g_raid_tr_raid1_rebuild_abort(struct g_raid_tr_object *tr)
 313 {
 314         struct g_raid_tr_raid1_object *trs;
 315         struct g_raid_subdisk *sd;
 316         struct g_raid_volume *vol;
 317         off_t len;
 318
 319         vol = tr->tro_volume;
 320         trs = (struct g_raid_tr_raid1_object *)tr;
 321         sd = trs->trso_failed_sd;
 322         if (trs->trso_flags & TR_RAID1_F_DOING_SOME) {
 323                 G_RAID_DEBUG1(1, vol->v_softc,
 324                     "Subdisk %s:%d-%s rebuild is aborting.",
 325                     sd->sd_volume->v_name, sd->sd_pos,
 326                     sd->sd_disk ? g_raid_get_diskname(sd->sd_disk) : "[none]");
 327                 trs->trso_flags |= TR_RAID1_F_ABORT;
 328         } else {
 329                 G_RAID_DEBUG1(0, vol->v_softc,
 330                     "Subdisk %s:%d-%s rebuild aborted.",
 331                     sd->sd_volume->v_name, sd->sd_pos,
 332                     sd->sd_disk ? g_raid_get_diskname(sd->sd_disk) : "[none]");
 333                 trs->trso_flags &= ~TR_RAID1_F_ABORT;
 334                 if (trs->trso_flags & TR_RAID1_F_LOCKED) {
 335                         trs->trso_flags &= ~TR_RAID1_F_LOCKED;
 336                         len = MIN(g_raid1_rebuild_slab,
 337                             sd->sd_size - sd->sd_rebuild_pos);
 338                         g_raid_unlock_range(tr->tro_volume,
 339                             sd->sd_rebuild_pos, len);
 340                 }
 341                 g_raid_tr_raid1_rebuild_done(trs);
 342         }
 343 }
 344
 345 static void
 346 g_raid_tr_raid1_rebuild_start(struct g_raid_tr_object *tr)
 347 {
 348         struct g_raid_volume *vol;
 349         struct g_raid_tr_raid1_object *trs;
 350         struct g_raid_subdisk *sd, *fsd;
 351
 352         vol = tr->tro_volume;
 353         trs = (struct g_raid_tr_raid1_object *)tr;
 354         if (trs->trso_failed_sd) {
 355                 G_RAID_DEBUG1(1, vol->v_softc,
 356                     "Already rebuild in start rebuild. pos %jd\n",
 357                     (intmax_t)trs->trso_failed_sd->sd_rebuild_pos);
 358                 return;
 359         }
 360         sd = g_raid_get_subdisk(vol, G_RAID_SUBDISK_S_ACTIVE);
 361         if (sd == NULL) {
 362                 G_RAID_DEBUG1(1, vol->v_softc,
 363                     "No active disk to rebuild.  night night.");
 364                 return;
 365         }
 366         fsd = g_raid_get_subdisk(vol, G_RAID_SUBDISK_S_RESYNC);
 367         if (fsd == NULL)
 368                 fsd = g_raid_get_subdisk(vol, G_RAID_SUBDISK_S_REBUILD);
 369         if (fsd == NULL) {
 370                 fsd = g_raid_get_subdisk(vol, G_RAID_SUBDISK_S_STALE);
 371                 if (fsd != NULL) {
 372                         fsd->sd_rebuild_pos = 0;
 373                         g_raid_change_subdisk_state(fsd,
 374                             G_RAID_SUBDISK_S_RESYNC);
 375                         g_raid_write_metadata(vol->v_softc, vol, fsd, NULL);
 376                 } else {
 377                         fsd = g_raid_get_subdisk(vol,
 378                             G_RAID_SUBDISK_S_UNINITIALIZED);
 379                         if (fsd == NULL)
 380                                 fsd = g_raid_get_subdisk(vol,
 381                                     G_RAID_SUBDISK_S_NEW);
 382                         if (fsd != NULL) {
 383                                 fsd->sd_rebuild_pos = 0;
 384                                 g_raid_change_subdisk_state(fsd,
 385                                     G_RAID_SUBDISK_S_REBUILD);
 386                                 g_raid_write_metadata(vol->v_softc,
 387                                     vol, fsd, NULL);
 388                         }
 389                 }
 390         }
 391         if (fsd == NULL) {
 392                 G_RAID_DEBUG1(1, vol->v_softc,
 393                     "No failed disk to rebuild.  night night.");
 394                 return;
 395         }
 396         trs->trso_failed_sd = fsd;
 397         G_RAID_DEBUG1(0, vol->v_softc,
 398             "Subdisk %s:%d-%s rebuild start at %jd.",
 399             fsd->sd_volume->v_name, fsd->sd_pos,
 400             fsd->sd_disk ? g_raid_get_diskname(fsd->sd_disk) : "[none]",
 401             trs->trso_failed_sd->sd_rebuild_pos);
 402         trs->trso_type = TR_RAID1_REBUILD;
 403         trs->trso_buffer = malloc(g_raid1_rebuild_slab, M_TR_RAID1, M_WAITOK);
 404         trs->trso_meta_update = g_raid1_rebuild_meta_update;
 405         g_raid_tr_raid1_rebuild_some(tr);
 406 }
 407
 408
 409 static void
 410 g_raid_tr_raid1_maybe_rebuild(struct g_raid_tr_object *tr,
 411     struct g_raid_subdisk *sd)
 412 {
 413         struct g_raid_volume *vol;
 414         struct g_raid_tr_raid1_object *trs;
 415         int na, nr;
 416
 417         /*
 418          * If we're stopping, don't do anything.  If we don't have at least one
 419          * good disk and one bad disk, we don't do anything.  And if there's a
 420          * 'good disk' stored in the trs, then we're in progress and we punt.
 421          * If we make it past all these checks, we need to rebuild.
 422          */
 423         vol = tr->tro_volume;
 424         trs = (struct g_raid_tr_raid1_object *)tr;
 425         if (trs->trso_stopping)
 426                 return;
 427         na = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_ACTIVE);
 428         nr = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_REBUILD) +
 429             g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_RESYNC);
 430         switch(trs->trso_type) {
 431         case TR_RAID1_NONE:
 432                 if (na == 0)
 433                         return;
 434                 if (nr == 0) {
 435                         nr = g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_NEW) +
 436                             g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_STALE) +
 437                             g_raid_nsubdisks(vol, G_RAID_SUBDISK_S_UNINITIALIZED);
 438                         if (nr == 0)
 439                                 return;
 440                 }
 441                 g_raid_tr_raid1_rebuild_start(tr);
 442                 break;
 443         case TR_RAID1_REBUILD:
 444                 if (na == 0 || nr == 0 || trs->trso_failed_sd == sd)
 445                         g_raid_tr_raid1_rebuild_abort(tr);
 446                 break;
 447         case TR_RAID1_RESYNC:
 448                 break;
 449         }
 450 }
 451
 452 static int
 453 g_raid_tr_event_raid1(struct g_raid_tr_object *tr,
 454     struct g_raid_subdisk *sd, u_int event)
 455 {
 456
 457         g_raid_tr_update_state_raid1(tr->tro_volume, sd);
 458         return (0);
 459 }
 460
 461 static int
 462 g_raid_tr_start_raid1(struct g_raid_tr_object *tr)
 463 {
 464         struct g_raid_tr_raid1_object *trs;
 465         struct g_raid_volume *vol;
 466
 467         trs = (struct g_raid_tr_raid1_object *)tr;
 468         vol = tr->tro_volume;
 469         trs->trso_starting = 0;
 470         g_raid_tr_update_state_raid1(vol, NULL);
 471         return (0);
 472 }
 473
 474 static int
 475 g_raid_tr_stop_raid1(struct g_raid_tr_object *tr)
 476 {
 477         struct g_raid_tr_raid1_object *trs;
 478         struct g_raid_volume *vol;
 479
 480         trs = (struct g_raid_tr_raid1_object *)tr;
 481         vol = tr->tro_volume;
 482         trs->trso_starting = 0;
 483         trs->trso_stopping = 1;
 484         g_raid_tr_update_state_raid1(vol, NULL);
 485         return (0);
 486 }
 487
 488 /*
 489  * Select the disk to read from.  Take into account: subdisk state, running
 490  * error recovery, average disk load, head position and possible cache hits.
 491  */
 492 #define ABS(x)          (((x) >= 0) ? (x) : (-(x)))
 493 static struct g_raid_subdisk *
 494 g_raid_tr_raid1_select_read_disk(struct g_raid_volume *vol, struct bio *bp,
 495     u_int mask)
 496 {
 497         struct g_raid_subdisk *sd, *best;
 498         int i, prio, bestprio;
 499
 500         best = NULL;
 501         bestprio = INT_MAX;
 502         for (i = 0; i < vol->v_disks_count; i++) {
 503                 sd = &vol->v_subdisks[i];
 504                 if (sd->sd_state != G_RAID_SUBDISK_S_ACTIVE &&
 505                     ((sd->sd_state != G_RAID_SUBDISK_S_REBUILD &&
 506                       sd->sd_state != G_RAID_SUBDISK_S_RESYNC) ||
 507                      bp->bio_offset + bp->bio_length > sd->sd_rebuild_pos))
 508                         continue;
 509                 if ((mask & (1 << i)) != 0)
 510                         continue;
 511                 prio = G_RAID_SUBDISK_LOAD(sd);
 512                 prio += min(sd->sd_recovery, 255) << 22;
 513                 prio += (G_RAID_SUBDISK_S_ACTIVE - sd->sd_state) << 16;
 514                 /* If disk head is precisely in position - highly prefer it. */
 515                 if (G_RAID_SUBDISK_POS(sd) == bp->bio_offset)
 516                         prio -= 2 * G_RAID_SUBDISK_LOAD_SCALE;
 517                 else
 518                 /* If disk head is close to position - prefer it. */
 519                 if (ABS(G_RAID_SUBDISK_POS(sd) - bp->bio_offset) <
 520                     G_RAID_SUBDISK_TRACK_SIZE)
 521                         prio -= 1 * G_RAID_SUBDISK_LOAD_SCALE;
 522                 if (prio < bestprio) {
 523                         best = sd;
 524                         bestprio = prio;
 525                 }
 526         }
 527         return (best);
 528 }
 529
 530 static void
 531 g_raid_tr_iostart_raid1_read(struct g_raid_tr_object *tr, struct bio *bp)
 532 {
 533         struct g_raid_subdisk *sd;
 534         struct bio *cbp;
 535
 536         sd = g_raid_tr_raid1_select_read_disk(tr->tro_volume, bp, 0);
 537         KASSERT(sd != NULL, ("No active disks in volume %s.",
 538                 tr->tro_volume->v_name));
 539
 540         cbp = g_clone_bio(bp);
 541         if (cbp == NULL) {
 542                 g_raid_iodone(bp, ENOMEM);
 543                 return;
 544         }
 545
 546         g_raid_subdisk_iostart(sd, cbp);
 547 }
 548
 549 static void
 550 g_raid_tr_iostart_raid1_write(struct g_raid_tr_object *tr, struct bio *bp)
 551 {
 552         struct g_raid_volume *vol;
 553         struct g_raid_subdisk *sd;
 554         struct bio_queue_head queue;
 555         struct bio *cbp;
 556         int i;
 557
 558         vol = tr->tro_volume;
 559
 560         /*
 561          * Allocate all bios before sending any request, so we can return
 562          * ENOMEM in nice and clean way.
 563          */
 564         bioq_init(&queue);
 565         for (i = 0; i < vol->v_disks_count; i++) {
 566                 sd = &vol->v_subdisks[i];
 567                 switch (sd->sd_state) {
 568                 case G_RAID_SUBDISK_S_ACTIVE:
 569                         break;
 570                 case G_RAID_SUBDISK_S_REBUILD:
 571                         /*
 572                          * When rebuilding, only part of this subdisk is
 573                          * writable, the rest will be written as part of the
 574                          * that process.
 575                          */
 576                         if (bp->bio_offset >= sd->sd_rebuild_pos)
 577                                 continue;
 578                         break;
 579                 case G_RAID_SUBDISK_S_STALE:
 580                 case G_RAID_SUBDISK_S_RESYNC:
 581                         /*
 582                          * Resyncing still writes on the theory that the
 583                          * resync'd disk is very close and writing it will
 584                          * keep it that way better if we keep up while
 585                          * resyncing.
 586                          */
 587                         break;
 588                 default:
 589                         continue;
 590                 }
 591                 cbp = g_clone_bio(bp);
 592                 if (cbp == NULL)
 593                         goto failure;
 594                 cbp->bio_caller1 = sd;
 595                 bioq_insert_tail(&queue, cbp);
 596         }
 597         for (cbp = bioq_first(&queue); cbp != NULL;
 598             cbp = bioq_first(&queue)) {
 599                 bioq_remove(&queue, cbp);
 600                 sd = cbp->bio_caller1;
 601                 cbp->bio_caller1 = NULL;
 602                 g_raid_subdisk_iostart(sd, cbp);
 603         }
 604         return;
 605 failure:
 606         for (cbp = bioq_first(&queue); cbp != NULL;
 607             cbp = bioq_first(&queue)) {
 608                 bioq_remove(&queue, cbp);
 609                 g_destroy_bio(cbp);
 610         }
 611         if (bp->bio_error == 0)
 612                 bp->bio_error = ENOMEM;
 613         g_raid_iodone(bp, bp->bio_error);
 614 }
 615
 616 static void
 617 g_raid_tr_iostart_raid1(struct g_raid_tr_object *tr, struct bio *bp)
 618 {
 619         struct g_raid_volume *vol;
 620         struct g_raid_tr_raid1_object *trs;
 621
 622         vol = tr->tro_volume;
 623         trs = (struct g_raid_tr_raid1_object *)tr;
 624         if (vol->v_state != G_RAID_VOLUME_S_OPTIMAL &&
 625             vol->v_state != G_RAID_VOLUME_S_SUBOPTIMAL &&
 626             vol->v_state != G_RAID_VOLUME_S_DEGRADED) {
 627                 g_raid_iodone(bp, EIO);
 628                 return;
 629         }
 630         /*
 631          * If we're rebuilding, squeeze in rebuild activity every so often,
 632          * even when the disk is busy.  Be sure to only count real I/O
 633          * to the disk.  All 'SPECIAL' I/O is traffic generated to the disk
 634          * by this module.
 635          */
 636         if (trs->trso_failed_sd != NULL &&
 637             !(bp->bio_cflags & G_RAID_BIO_FLAG_SPECIAL)) {
 638                 /* Make this new or running now round short. */
 639                 trs->trso_recover_slabs = 0;
 640                 if (--trs->trso_fair_io <= 0) {
 641                         trs->trso_fair_io = g_raid1_rebuild_fair_io;
 642                         g_raid_tr_raid1_rebuild_some(tr);
 643                 }
 644         }
 645         switch (bp->bio_cmd) {
 646         case BIO_READ:
 647                 g_raid_tr_iostart_raid1_read(tr, bp);
 648                 break;
 649         case BIO_WRITE:
 650         case BIO_DELETE:
 651                 g_raid_tr_iostart_raid1_write(tr, bp);
 652                 break;
 653         case BIO_FLUSH:
 654                 g_raid_tr_flush_common(tr, bp);
 655                 break;
 656         default:
 657                 KASSERT(1 == 0, ("Invalid command here: %u (volume=%s)",
 658                     bp->bio_cmd, vol->v_name));
 659                 break;
 660         }
 661 }
 662
 663 static void
 664 g_raid_tr_iodone_raid1(struct g_raid_tr_object *tr,
 665     struct g_raid_subdisk *sd, struct bio *bp)
 666 {
 667         struct bio *cbp;
 668         struct g_raid_subdisk *nsd;
 669         struct g_raid_volume *vol;
 670         struct bio *pbp;
 671         struct g_raid_tr_raid1_object *trs;
 672         uintptr_t *mask;
 673         int error, do_write;
 674
 675         trs = (struct g_raid_tr_raid1_object *)tr;
 676         vol = tr->tro_volume;
 677         if (bp->bio_cflags & G_RAID_BIO_FLAG_SYNC) {
 678                 /*
 679                  * This operation is part of a rebuild or resync operation.
 680                  * See what work just got done, then schedule the next bit of
 681                  * work, if any.  Rebuild/resync is done a little bit at a
 682                  * time.  Either when a timeout happens, or after we get a
 683                  * bunch of I/Os to the disk (to make sure an active system
 684                  * will complete in a sane amount of time).
 685                  *
 686                  * We are setup to do differing amounts of work for each of
 687                  * these cases.  so long as the slabs is smallish (less than
 688                  * 50 or so, I'd guess, but that's just a WAG), we shouldn't
 689                  * have any bio starvation issues.  For active disks, we do
 690                  * 5MB of data, for inactive ones, we do 50MB.
 691                  */
 692                 if (trs->trso_type == TR_RAID1_REBUILD) {
 693                         if (bp->bio_cmd == BIO_READ) {
 694
 695                                 /* Immediately abort rebuild, if requested. */
 696                                 if (trs->trso_flags & TR_RAID1_F_ABORT) {
 697                                         trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
 698                                         g_raid_tr_raid1_rebuild_abort(tr);
 699                                         return;
 700                                 }
 701
 702                                 /* On read error, skip and cross fingers. */
 703                                 if (bp->bio_error != 0) {
 704                                         G_RAID_LOGREQ(0, bp,
 705                                             "Read error during rebuild (%d), "
 706                                             "possible data loss!",
 707                                             bp->bio_error);
 708                                         goto rebuild_round_done;
 709                                 }
 710
 711                                 /*
 712                                  * The read operation finished, queue the
 713                                  * write and get out.
 714                                  */
 715                                 G_RAID_LOGREQ(4, bp, "rebuild read done. %d",
 716                                     bp->bio_error);
 717                                 bp->bio_cmd = BIO_WRITE;
 718                                 bp->bio_cflags = G_RAID_BIO_FLAG_SYNC;
 719                                 G_RAID_LOGREQ(4, bp, "Queueing rebuild write.");
 720                                 g_raid_subdisk_iostart(trs->trso_failed_sd, bp);
 721                         } else {
 722                                 /*
 723                                  * The write operation just finished.  Do
 724                                  * another.  We keep cloning the master bio
 725                                  * since it has the right buffers allocated to
 726                                  * it.
 727                                  */
 728                                 G_RAID_LOGREQ(4, bp,
 729                                     "rebuild write done. Error %d",
 730                                     bp->bio_error);
 731                                 nsd = trs->trso_failed_sd;
 732                                 if (bp->bio_error != 0 ||
 733                                     trs->trso_flags & TR_RAID1_F_ABORT) {
 734                                         if ((trs->trso_flags &
 735                                             TR_RAID1_F_ABORT) == 0) {
 736                                                 g_raid_tr_raid1_fail_disk(sd->sd_softc,
 737                                                     nsd, nsd->sd_disk);
 738                                         }
 739                                         trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
 740                                         g_raid_tr_raid1_rebuild_abort(tr);
 741                                         return;
 742                                 }
 743 rebuild_round_done:
 744                                 nsd = trs->trso_failed_sd;
 745                                 trs->trso_flags &= ~TR_RAID1_F_LOCKED;
 746                                 g_raid_unlock_range(sd->sd_volume,
 747                                     bp->bio_offset, bp->bio_length);
 748                                 nsd->sd_rebuild_pos += bp->bio_length;
 749                                 if (nsd->sd_rebuild_pos >= nsd->sd_size) {
 750                                         g_raid_tr_raid1_rebuild_finish(tr);
 751                                         return;
 752                                 }
 753
 754                                 /* Abort rebuild if we are stopping */
 755                                 if (trs->trso_stopping) {
 756                                         trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
 757                                         g_raid_tr_raid1_rebuild_abort(tr);
 758                                         return;
 759                                 }
 760
 761                                 if (--trs->trso_meta_update <= 0) {
 762                                         g_raid_write_metadata(vol->v_softc,
 763                                             vol, nsd, nsd->sd_disk);
 764                                         trs->trso_meta_update =
 765                                             g_raid1_rebuild_meta_update;
 766                                 }
 767                                 trs->trso_flags &= ~TR_RAID1_F_DOING_SOME;
 768                                 if (--trs->trso_recover_slabs <= 0)
 769                                         return;
 770                                 g_raid_tr_raid1_rebuild_some(tr);
 771                         }
 772                 } else if (trs->trso_type == TR_RAID1_RESYNC) {
 773                         /*
 774                          * read good sd, read bad sd in parallel.  when both
 775                          * done, compare the buffers.  write good to the bad
 776                          * if different.  do the next bit of work.
 777                          */
 778                         panic("Somehow, we think we're doing a resync");
 779                 }
 780                 return;
 781         }
 782         pbp = bp->bio_parent;
 783         pbp->bio_inbed++;
 784         if (bp->bio_cmd == BIO_READ && bp->bio_error != 0) {
 785                 /*
 786                  * Read failed on first drive.  Retry the read error on
 787                  * another disk drive, if available, before erroring out the
 788                  * read.
 789                  */
 790                 sd->sd_disk->d_read_errs++;
 791                 G_RAID_LOGREQ(0, bp,
 792                     "Read error (%d), %d read errors total",
 793                     bp->bio_error, sd->sd_disk->d_read_errs);
 794
 795                 /*
 796                  * If there are too many read errors, we move to degraded.
 797                  * XXX Do we want to FAIL the drive (eg, make the user redo
 798                  * everything to get it back in sync), or just degrade the
 799                  * drive, which kicks off a resync?
 800                  */
 801                 do_write = 1;
 802                 if (sd->sd_disk->d_read_errs > g_raid_read_err_thresh) {
 803                         g_raid_tr_raid1_fail_disk(sd->sd_softc, sd, sd->sd_disk);
 804                         if (pbp->bio_children == 1)
 805                                 do_write = 0;
 806                 }
 807
 808                 /*
 809                  * Find the other disk, and try to do the I/O to it.
 810                  */
 811                 mask = (uintptr_t *)(&pbp->bio_driver2);
 812                 if (pbp->bio_children == 1) {
 813                         /* Save original subdisk. */
 814                         pbp->bio_driver1 = do_write ? sd : NULL;
 815                         *mask = 0;
 816                 }
 817                 *mask |= 1 << sd->sd_pos;
 818                 nsd = g_raid_tr_raid1_select_read_disk(vol, pbp, *mask);
 819                 if (nsd != NULL && (cbp = g_clone_bio(pbp)) != NULL) {
 820                         g_destroy_bio(bp);
 821                         G_RAID_LOGREQ(2, cbp, "Retrying read from %d",
 822                             nsd->sd_pos);
 823                         if (pbp->bio_children == 2 && do_write) {
 824                                 sd->sd_recovery++;
 825                                 cbp->bio_caller1 = nsd;
 826                                 pbp->bio_pflags = G_RAID_BIO_FLAG_LOCKED;
 827                                 /* Lock callback starts I/O */
 828                                 g_raid_lock_range(sd->sd_volume,
 829                                     cbp->bio_offset, cbp->bio_length, pbp, cbp);
 830                         } else {
 831                                 g_raid_subdisk_iostart(nsd, cbp);
 832                         }
 833                         return;
 834                 }
 835                 /*
 836                  * We can't retry.  Return the original error by falling
 837                  * through.  This will happen when there's only one good disk.
 838                  * We don't need to fail the raid, since its actual state is
 839                  * based on the state of the subdisks.
 840                  */
 841                 G_RAID_LOGREQ(2, bp, "Couldn't retry read, failing it");
 842         }
 843         if (bp->bio_cmd == BIO_READ &&
 844             bp->bio_error == 0 &&
 845             pbp->bio_children > 1 &&
 846             pbp->bio_driver1 != NULL) {
 847                 /*
 848                  * If it was a read, and bio_children is >1, then we just
 849                  * recovered the data from the second drive.  We should try to
 850                  * write that data to the first drive if sector remapping is
 851                  * enabled.  A write should put the data in a new place on the
 852                  * disk, remapping the bad sector.  Do we need to do that by
 853                  * queueing a request to the main worker thread?  It doesn't
 854                  * affect the return code of this current read, and can be
 855                  * done at our liesure.  However, to make the code simpler, it
 856                  * is done syncrhonously.
 857                  */
 858                 G_RAID_LOGREQ(3, bp, "Recovered data from other drive");
 859                 cbp = g_clone_bio(pbp);
 860                 if (cbp != NULL) {
 861                         g_destroy_bio(bp);
 862                         cbp->bio_cmd = BIO_WRITE;
 863                         cbp->bio_cflags = G_RAID_BIO_FLAG_REMAP;
 864                         G_RAID_LOGREQ(2, cbp,
 865                             "Attempting bad sector remap on failing drive.");
 866                         g_raid_subdisk_iostart(pbp->bio_driver1, cbp);
 867                         return;
 868                 }
 869         }
 870         if (pbp->bio_pflags & G_RAID_BIO_FLAG_LOCKED) {
 871                 /*
 872                  * We're done with a recovery, mark the range as unlocked.
 873                  * For any write errors, we agressively fail the disk since
 874                  * there was both a READ and a WRITE error at this location.
 875                  * Both types of errors generally indicates the drive is on
 876                  * the verge of total failure anyway.  Better to stop trusting
 877                  * it now.  However, we need to reset error to 0 in that case
 878                  * because we're not failing the original I/O which succeeded.
 879                  */
 880                 if (bp->bio_cmd == BIO_WRITE && bp->bio_error) {
 881                         G_RAID_LOGREQ(0, bp, "Remap write failed: "
 882                             "failing subdisk.");
 883                         g_raid_tr_raid1_fail_disk(sd->sd_softc, sd, sd->sd_disk);
 884                         bp->bio_error = 0;
 885                 }
 886                 if (pbp->bio_driver1 != NULL) {
 887                         ((struct g_raid_subdisk *)pbp->bio_driver1)
 888                             ->sd_recovery--;
 889                 }
 890                 G_RAID_LOGREQ(2, bp, "REMAP done %d.", bp->bio_error);
 891                 g_raid_unlock_range(sd->sd_volume, bp->bio_offset,
 892                     bp->bio_length);
 893         }
 894         if (pbp->bio_cmd != BIO_READ) {
 895                 if (pbp->bio_inbed == 1 || pbp->bio_error != 0)
 896                         pbp->bio_error = bp->bio_error;
 897                 if (pbp->bio_cmd == BIO_WRITE && bp->bio_error != 0) {
 898                         G_RAID_LOGREQ(0, bp, "Write failed: failing subdisk.");
 899                         g_raid_tr_raid1_fail_disk(sd->sd_softc, sd, sd->sd_disk);
 900                 }
 901                 error = pbp->bio_error;
 902         } else
 903                 error = bp->bio_error;
 904         g_destroy_bio(bp);
 905         if (pbp->bio_children == pbp->bio_inbed) {
 906                 pbp->bio_completed = pbp->bio_length;
 907                 g_raid_iodone(pbp, error);
 908         }
 909 }
 910
 911 static int
 912 g_raid_tr_kerneldump_raid1(struct g_raid_tr_object *tr,
 913     void *virtual, vm_offset_t physical, off_t offset, size_t length)
 914 {
 915         struct g_raid_volume *vol;
 916         struct g_raid_subdisk *sd;
 917         int error, i, ok;
 918
 919         vol = tr->tro_volume;
 920         error = 0;
 921         ok = 0;
 922         for (i = 0; i < vol->v_disks_count; i++) {
 923                 sd = &vol->v_subdisks[i];
 924                 switch (sd->sd_state) {
 925                 case G_RAID_SUBDISK_S_ACTIVE:
 926                         break;
 927                 case G_RAID_SUBDISK_S_REBUILD:
 928                         /*
 929                          * When rebuilding, only part of this subdisk is
 930                          * writable, the rest will be written as part of the
 931                          * that process.
 932                          */
 933                         if (offset >= sd->sd_rebuild_pos)
 934                                 continue;
 935                         break;
 936                 case G_RAID_SUBDISK_S_STALE:
 937                 case G_RAID_SUBDISK_S_RESYNC:
 938                         /*
 939                          * Resyncing still writes on the theory that the
 940                          * resync'd disk is very close and writing it will
 941                          * keep it that way better if we keep up while
 942                          * resyncing.
 943                          */
 944                         break;
 945                 default:
 946                         continue;
 947                 }
 948                 error = g_raid_subdisk_kerneldump(sd,
 949                     virtual, physical, offset, length);
 950                 if (error == 0)
 951                         ok++;
 952         }
 953         return (ok > 0 ? 0 : error);
 954 }
 955
 956 static int
 957 g_raid_tr_locked_raid1(struct g_raid_tr_object *tr, void *argp)
 958 {
 959         struct bio *bp;
 960         struct g_raid_subdisk *sd;
 961
 962         bp = (struct bio *)argp;
 963         sd = (struct g_raid_subdisk *)bp->bio_caller1;
 964         g_raid_subdisk_iostart(sd, bp);
 965
 966         return (0);
 967 }
 968
 969 static int
 970 g_raid_tr_idle_raid1(struct g_raid_tr_object *tr)
 971 {
 972         struct g_raid_tr_raid1_object *trs;
 973
 974         trs = (struct g_raid_tr_raid1_object *)tr;
 975         trs->trso_fair_io = g_raid1_rebuild_fair_io;
 976         trs->trso_recover_slabs = g_raid1_rebuild_cluster_idle;
 977         if (trs->trso_type == TR_RAID1_REBUILD)
 978                 g_raid_tr_raid1_rebuild_some(tr);
 979         return (0);
 980 }
 981
 982 static int
 983 g_raid_tr_free_raid1(struct g_raid_tr_object *tr)
 984 {
 985         struct g_raid_tr_raid1_object *trs;
 986
 987         trs = (struct g_raid_tr_raid1_object *)tr;
 988
 989         if (trs->trso_buffer != NULL) {
 990                 free(trs->trso_buffer, M_TR_RAID1);
 991                 trs->trso_buffer = NULL;
 992         }
 993         return (0);
 994 }
 995
 996 G_RAID_TR_DECLARE(raid1, "RAID1");