Assemble.c

   1 /*
   2  * mdadm - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001-2002 Neil Brown <neilb@cse.unsw.edu.au>
   5  *
   6  *
   7  *    This program is free software; you can redistribute it and/or modify
   8  *    it under the terms of the GNU General Public License as published by
   9  *    the Free Software Foundation; either version 2 of the License, or
  10  *    (at your option) any later version.
  11  *
  12  *    This program is distributed in the hope that it will be useful,
  13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *    GNU General Public License for more details.
  16  *
  17  *    You should have received a copy of the GNU General Public License
  18  *    along with this program; if not, write to the Free Software
  19  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  *    Author: Neil Brown
  22  *    Email: <neilb@cse.unsw.edu.au>
  23  *    Paper: Neil Brown
  24  *           School of Computer Science and Engineering
  25  *           The University of New South Wales
  26  *           Sydney, 2052
  27  *           Australia
  28  */
  29
  30 #include        "mdadm.h"
  31
  32 int Assemble(struct supertype *st, char *mddev, int mdfd,
  33              mddev_ident_t ident, char *conffile,
  34              mddev_dev_t devlist,
  35              int readonly, int runstop,
  36              char *update,
  37              int verbose, int force)
  38 {
  39         /*
  40          * The task of Assemble is to find a collection of
  41          * devices that should (according to their superblocks)
  42          * form an array, and to give this collection to the MD driver.
  43          * In Linux-2.4 and later, this involves submitting a
  44          * SET_ARRAY_INFO ioctl with no arg - to prepare
  45          * the array - and then submit a number of
  46          * ADD_NEW_DISK ioctls to add disks into
  47          * the array.  Finally RUN_ARRAY might
  48          * be submitted to start the array.
  49          *
  50          * Much of the work of Assemble is in finding and/or
  51          * checking the disks to make sure they look right.
  52          *
  53          * If mddev is not set, then scan must be set and we
  54          *  read through the config file for dev+uuid mapping
  55          *  We recurse, setting mddev, for each device that
  56          *    - isn't running
  57          *    - has a valid uuid (or any uuid if !uuidset)
  58          *
  59          * If mddev is set, we try to determine state of md.
  60          *   check version - must be at least 0.90.0
  61          *   check kernel version.  must be at least 2.4.
  62          *    If not, we can possibly fall back on START_ARRAY
  63          *   Try to GET_ARRAY_INFO.
  64          *     If possible, give up
  65          *     If not, try to STOP_ARRAY just to make sure
  66          *
  67          * If !uuidset and scan, look in conf-file for uuid
  68          *       If not found, give up
  69          * If !devlist and scan and uuidset, get list of devs from conf-file
  70          *
  71          * For each device:
  72          *   Check superblock - discard if bad
  73          *   Check uuid (set if we don't have one) - discard if no match
  74          *   Check superblock similarity if we have a superblock - discard if different
  75          *   Record events, devicenum
  76          * This should give us a list of devices for the array
  77          * We should collect the most recent event number
  78          *
  79          * Count disks with recent enough event count
  80          * While force && !enough disks
  81          *    Choose newest rejected disks, update event count
  82          *     mark clean and rewrite superblock
  83          * If recent kernel:
  84          *    SET_ARRAY_INFO
  85          *    foreach device with recent events : ADD_NEW_DISK
  86          *    if runstop == 1 || "enough" disks and runstop==0 -> RUN_ARRAY
  87          * If old kernel:
  88          *    Check the device numbers in superblock are right
  89          *    update superblock if any changes
  90          *    START_ARRAY
  91          *
  92          */
  93         int old_linux = 0;
  94         int vers;
  95         void *first_super = NULL, *super = NULL;
  96         struct {
  97                 char *devname;
  98                 unsigned int major, minor;
  99                 unsigned int oldmajor, oldminor;
 100                 long long events;
 101                 int uptodate;
 102                 int state;
 103                 int raid_disk;
 104                 int disk_nr;
 105         } *devices;
 106         int *best = NULL; /* indexed by raid_disk */
 107         unsigned int bestcnt = 0;
 108         int devcnt = 0;
 109         unsigned int okcnt, sparecnt;
 110         unsigned int req_cnt;
 111         unsigned int i;
 112         int most_recent = 0;
 113         int chosen_drive;
 114         int change = 0;
 115         int inargv = 0;
 116         int start_partial_ok = force || devlist==NULL;
 117         unsigned int num_devs;
 118         mddev_dev_t tmpdev;
 119         struct mdinfo info;
 120         struct mddev_ident_s ident2;
 121         char *avail;
 122
 123         vers = md_get_version(mdfd);
 124         if (vers <= 0) {
 125                 fprintf(stderr, Name ": %s appears not to be an md device.\n", mddev);
 126                 return 1;
 127         }
 128         if (vers < 9000) {
 129                 fprintf(stderr, Name ": Assemble requires driver version 0.90.0 or later.\n"
 130                         "    Upgrade your kernel or try --build\n");
 131                 return 1;
 132         }
 133         if (get_linux_version() < 2004000)
 134                 old_linux = 1;
 135
 136         if (ioctl(mdfd, GET_ARRAY_INFO, &info.array)>=0) {
 137                 fprintf(stderr, Name ": device %s already active - cannot assemble it\n",
 138                         mddev);
 139                 return 1;
 140         }
 141         ioctl(mdfd, STOP_ARRAY, NULL); /* just incase it was started but has no content */
 142
 143         /*
 144          * If any subdevs are listed, then any that don't
 145          * match ident are discarded.  Remainder must all match and
 146          * become the array.
 147          * If no subdevs, then we scan all devices in the config file, but
 148          * there must be something in the identity
 149          */
 150
 151         if (!devlist &&
 152             ident->uuid_set == 0 &&
 153             ident->super_minor < 0 &&
 154             ident->devices == NULL) {
 155                 fprintf(stderr, Name ": No identity information available for %s - cannot assemble.\n",
 156                         mddev);
 157                 return 1;
 158         }
 159         if (devlist == NULL)
 160                 devlist = conf_get_devs(conffile);
 161         else inargv = 1;
 162
 163         tmpdev = devlist; num_devs = 0;
 164         while (tmpdev) {
 165                 num_devs++;
 166                 tmpdev = tmpdev->next;
 167         }
 168         devices = malloc(num_devs * sizeof(*devices));
 169
 170         if (!st && ident->st) st = ident->st;
 171
 172         if (verbose>0)
 173             fprintf(stderr, Name ": looking for devices for %s\n",
 174                     mddev);
 175
 176         while ( devlist) {
 177                 char *devname;
 178                 int dfd;
 179                 struct stat stb;
 180                 struct supertype *tst = st;
 181
 182                 devname = devlist->devname;
 183                 devlist = devlist->next;
 184
 185                 if (ident->devices &&
 186                     !match_oneof(ident->devices, devname)) {
 187                         if ((inargv && verbose>=0) || verbose > 0)
 188                                 fprintf(stderr, Name ": %s is not one of %s\n", devname, ident->devices);
 189                         continue;
 190                 }
 191
 192                 if (super) {
 193                         free(super);
 194                         super = NULL;
 195                 }
 196
 197                 dfd = open(devname, O_RDONLY|O_EXCL, 0);
 198                 if (dfd < 0) {
 199                         if ((inargv && verbose >= 0) || verbose > 0)
 200                                 fprintf(stderr, Name ": cannot open device %s: %s\n",
 201                                         devname, strerror(errno));
 202                 } else if (fstat(dfd, &stb)< 0) {
 203                         /* Impossible! */
 204                         fprintf(stderr, Name ": fstat failed for %s: %s\n",
 205                                 devname, strerror(errno));
 206                         close(dfd);
 207                 } else if ((stb.st_mode & S_IFMT) != S_IFBLK) {
 208                         fprintf(stderr, Name ": %s is not a block device.\n",
 209                                 devname);
 210                         close(dfd);
 211                 } else if (!tst && (tst = guess_super(dfd)) == NULL) {
 212                         if ((inargv && verbose >= 0) || verbose > 0)
 213                                 fprintf(stderr, Name ": no recogniseable superblock\n");
 214                 } else if (tst->ss->load_super(tst,dfd, &super, NULL)) {
 215                         if ((inargv && verbose >= 0) || verbose > 0)
 216                                 fprintf( stderr, Name ": no RAID superblock on %s\n",
 217                                          devname);
 218                         close(dfd);
 219                 } else {
 220                         tst->ss->getinfo_super(&info, &ident2, super);
 221                         close(dfd);
 222                 }
 223
 224                 if (ident->uuid_set &&
 225                     (!super || same_uuid(info.uuid, ident->uuid, tst->ss->swapuuid)==0)) {
 226                         if ((inargv && verbose >= 0) || verbose > 0)
 227                                 fprintf(stderr, Name ": %s has wrong uuid.\n",
 228                                         devname);
 229                         continue;
 230                 }
 231                 if (ident->name[0] &&
 232                     (!super || strncmp(ident2.name, ident->name, 32)!=0)) {
 233                         if ((inargv && verbose >= 0) || verbose > 0)
 234                                 fprintf(stderr, Name ": %s has wrong name.\n",
 235                                         devname);
 236                         continue;
 237                 }
 238                 if (ident->super_minor != UnSet &&
 239                     (!super || ident->super_minor != info.array.md_minor)) {
 240                         if ((inargv && verbose >= 0) || verbose > 0)
 241                                 fprintf(stderr, Name ": %s has wrong super-minor.\n",
 242                                         devname);
 243                         continue;
 244                 }
 245                 if (ident->level != UnSet &&
 246                     (!super|| ident->level != info.array.level)) {
 247                         if ((inargv && verbose >= 0) || verbose > 0)
 248                                 fprintf(stderr, Name ": %s has wrong raid level.\n",
 249                                         devname);
 250                         continue;
 251                 }
 252                 if (ident->raid_disks != UnSet &&
 253                     (!super || ident->raid_disks!= info.array.raid_disks)) {
 254                         if ((inargv && verbose >= 0) || verbose > 0)
 255                                 fprintf(stderr, Name ": %s requires wrong number of drives.\n",
 256                                         devname);
 257                         continue;
 258                 }
 259
 260                 /* If we are this far, then we are commited to this device.
 261                  * If the super_block doesn't exist, or doesn't match others,
 262                  * then we cannot continue
 263                  */
 264
 265                 if (!super) {
 266                         fprintf(stderr, Name ": %s has no superblock - assembly aborted\n",
 267                                 devname);
 268                         free(first_super);
 269                         return 1;
 270                 }
 271                 st = tst; /* commit to this format, if haven't already */
 272                 if (st->ss->compare_super(&first_super, super)) {
 273                         fprintf(stderr, Name ": superblock on %s doesn't match others - assembly aborted\n",
 274                                 devname);
 275                         free(super);
 276                         free(first_super);
 277                         return 1;
 278                 }
 279
 280                 /* looks like a good enough match to update the super block if needed */
 281                 if (update) {
 282                         /* prepare useful information in info structures */
 283                         struct stat stb2;
 284                         fstat(mdfd, &stb2);
 285                         info.array.md_minor = minor(stb2.st_rdev);
 286
 287                         st->ss->update_super(&info, super, update, devname, verbose);
 288
 289                         dfd = open(devname, O_RDWR|O_EXCL, 0);
 290                         if (dfd < 0)
 291                                 fprintf(stderr, Name ": Cannot open %s for superblock update\n",
 292                                         devname);
 293                         else if (st->ss->store_super(st, dfd, super))
 294                                 fprintf(stderr, Name ": Could not re-write superblock on %s.\n",
 295                                         devname);
 296                         if (dfd >= 0)
 297                                 close(dfd);
 298                 }
 299
 300                 if (verbose > 0)
 301                         fprintf(stderr, Name ": %s is identified as a member of %s, slot %d.\n",
 302                                 devname, mddev, info.disk.raid_disk);
 303                 devices[devcnt].devname = devname;
 304                 devices[devcnt].major = major(stb.st_rdev);
 305                 devices[devcnt].minor = minor(stb.st_rdev);
 306                 devices[devcnt].oldmajor = info.disk.major;
 307                 devices[devcnt].oldminor = info.disk.minor;
 308                 devices[devcnt].events = info.events;
 309                 devices[devcnt].raid_disk = info.disk.raid_disk;
 310                 devices[devcnt].disk_nr = info.disk.number;
 311                 devices[devcnt].uptodate = 0;
 312                 devices[devcnt].state = info.disk.state;
 313                 if (most_recent < devcnt) {
 314                         if (devices[devcnt].events
 315                             > devices[most_recent].events)
 316                                 most_recent = devcnt;
 317                 }
 318                 if (info.array.level == -4)
 319                         /* with multipath, the raid_disk from the superblock is meaningless */
 320                         i = devcnt;
 321                 else
 322                         i = devices[devcnt].raid_disk;
 323                 if (i < 10000) {
 324                         if (i >= bestcnt) {
 325                                 unsigned int newbestcnt = i+10;
 326                                 int *newbest = malloc(sizeof(int)*newbestcnt);
 327                                 unsigned int c;
 328                                 for (c=0; c < newbestcnt; c++)
 329                                         if (c < bestcnt)
 330                                                 newbest[c] = best[c];
 331                                         else
 332                                                 newbest[c] = -1;
 333                                 if (best)free(best);
 334                                 best = newbest;
 335                                 bestcnt = newbestcnt;
 336                         }
 337                         if (best[i] == -1
 338                             || devices[best[i]].events < devices[devcnt].events)
 339                                 best[i] = devcnt;
 340                 }
 341                 devcnt++;
 342         }
 343
 344         if (super)
 345                 free(super);
 346         super = NULL;
 347
 348         if (update && strcmp(update, "byteorder")==0)
 349                 st->minor_version = 90;
 350
 351         if (devcnt == 0) {
 352                 fprintf(stderr, Name ": no devices found for %s\n",
 353                         mddev);
 354                 free(first_super);
 355                 return 1;
 356         }
 357
 358         st->ss->getinfo_super(&info, &ident2, first_super);
 359
 360         /* now we have some devices that might be suitable.
 361          * I wonder how many
 362          */
 363         avail = malloc(info.array.raid_disks);
 364         memset(avail, 0, info.array.raid_disks);
 365         okcnt = 0;
 366         sparecnt=0;
 367         for (i=0; i< bestcnt ;i++) {
 368                 int j = best[i];
 369                 int event_margin = !force;
 370                 if (j < 0) continue;
 371                 /* note: we ignore error flags in multipath arrays
 372                  * as they don't make sense
 373                  */
 374                 if (info.array.level != -4)
 375                         if (!(devices[j].state & (1<<MD_DISK_SYNC))) {
 376                                 if (!(devices[j].state & (1<<MD_DISK_FAULTY)))
 377                                         sparecnt++;
 378                                 continue;
 379                         }
 380                 if (devices[j].events+event_margin >=
 381                     devices[most_recent].events) {
 382                         devices[j].uptodate = 1;
 383                         if (i < info.array.raid_disks) {
 384                                 okcnt++;
 385                                 avail[i]=1;
 386                         } else
 387                                 sparecnt++;
 388                 }
 389         }
 390         while (force && !enough(info.array.level, info.array.raid_disks,
 391                                 info.array.layout,
 392                                 avail, okcnt)) {
 393                 /* Choose the newest best drive which is
 394                  * not up-to-date, update the superblock
 395                  * and add it.
 396                  */
 397                 int fd;
 398                 chosen_drive = -1;
 399                 for (i=0; i<info.array.raid_disks && i < bestcnt; i++) {
 400                         int j = best[i];
 401                         if (j>=0 &&
 402                             !devices[j].uptodate &&
 403                             devices[j].events > 0 &&
 404                             (chosen_drive < 0 ||
 405                              devices[j].events > devices[chosen_drive].events))
 406                                 chosen_drive = j;
 407                 }
 408                 if (chosen_drive < 0)
 409                         break;
 410                 if (verbose >= 0)
 411                         fprintf(stderr, Name ": forcing event count in %s(%d) from %d upto %d\n",
 412                                 devices[chosen_drive].devname, devices[chosen_drive].raid_disk,
 413                                 (int)(devices[chosen_drive].events),
 414                                 (int)(devices[most_recent].events));
 415                 fd = open(devices[chosen_drive].devname, O_RDWR|O_EXCL);
 416                 if (fd < 0) {
 417                         fprintf(stderr, Name ": Couldn't open %s for write - not updating\n",
 418                                 devices[chosen_drive].devname);
 419                         devices[chosen_drive].events = 0;
 420                         continue;
 421                 }
 422                 if (st->ss->load_super(st,fd, &super, NULL)) {
 423                         close(fd);
 424                         fprintf(stderr, Name ": RAID superblock disappeared from %s - not updating.\n",
 425                                 devices[chosen_drive].devname);
 426                         devices[chosen_drive].events = 0;
 427                         continue;
 428                 }
 429                 info.events = devices[most_recent].events;
 430                 st->ss->update_super(&info, super, "force", devices[chosen_drive].devname, verbose);
 431
 432                 if (st->ss->store_super(st, fd, super)) {
 433                         close(fd);
 434                         fprintf(stderr, Name ": Could not re-write superblock on %s\n",
 435                                 devices[chosen_drive].devname);
 436                         devices[chosen_drive].events = 0;
 437                         free(super);
 438                         continue;
 439                 }
 440                 close(fd);
 441                 devices[chosen_drive].events = devices[most_recent].events;
 442                 devices[chosen_drive].uptodate = 1;
 443                 avail[chosen_drive] = 1;
 444                 okcnt++;
 445                 free(super);
 446         }
 447
 448         /* Now we want to look at the superblock which the kernel will base things on
 449          * and compare the devices that we think are working with the devices that the
 450          * superblock thinks are working.
 451          * If there are differences and --force is given, then update this chosen
 452          * superblock.
 453          */
 454         chosen_drive = -1;
 455         super = NULL;
 456         for (i=0; chosen_drive < 0 && i<bestcnt; i++) {
 457                 int j = best[i];
 458                 int fd;
 459
 460                 if (j<0)
 461                         continue;
 462                 if (!devices[j].uptodate)
 463                         continue;
 464                 chosen_drive = j;
 465                 if ((fd=open(devices[j].devname, O_RDONLY|O_EXCL))< 0) {
 466                         fprintf(stderr, Name ": Cannot open %s: %s\n",
 467                                 devices[j].devname, strerror(errno));
 468                         return 1;
 469                 }
 470                 if (st->ss->load_super(st,fd, &super, NULL)) {
 471                         close(fd);
 472                         fprintf(stderr, Name ": RAID superblock has disappeared from %s\n",
 473                                 devices[j].devname);
 474                         return 1;
 475                 }
 476                 close(fd);
 477         }
 478         if (super == NULL) {
 479                 fprintf(stderr, Name ": No suitable drives found for %s\n", mddev);
 480                 return 1;
 481         }
 482         st->ss->getinfo_super(&info, &ident2, super);
 483         for (i=0; i<bestcnt; i++) {
 484                 int j = best[i];
 485                 unsigned int desired_state;
 486
 487                 if (i < info.array.raid_disks)
 488                         desired_state = (1<<MD_DISK_ACTIVE) | (1<<MD_DISK_SYNC);
 489                 else
 490                         desired_state = 0;
 491
 492                 if (j<0)
 493                         continue;
 494                 if (!devices[j].uptodate)
 495                         continue;
 496                 info.disk.number = devices[j].disk_nr;
 497                 info.disk.raid_disk = i;
 498                 info.disk.state = desired_state;
 499
 500                 if (devices[j].uptodate &&
 501                     st->ss->update_super(&info, super, "assemble", NULL, verbose)) {
 502                         if (force) {
 503                                 if (verbose >= 0)
 504                                         fprintf(stderr, Name ": "
 505                                                 "clearing FAULTY flag for device %d in %s for %s\n",
 506                                                 j, mddev, devices[j].devname);
 507                                 change = 1;
 508                         } else {
 509                                 if (verbose >= -1)
 510                                         fprintf(stderr, Name ": "
 511                                                 "device %d in %s has wrong state in superblock, but %s seems ok\n",
 512                                                 i, mddev, devices[j].devname);
 513                         }
 514                 }
 515 #if 0
 516                 if (!devices[j].uptodate &&
 517                     !(super.disks[i].state & (1 << MD_DISK_FAULTY))) {
 518                         fprintf(stderr, Name ": devices %d of %s is not marked FAULTY in superblock, but cannot be found\n",
 519                                 i, mddev);
 520                 }
 521 #endif
 522         }
 523         if (force && okcnt == info.array.raid_disks-1) {
 524                 /* FIXME check event count */
 525                 change += st->ss->update_super(&info, super, "force",
 526                                         devices[chosen_drive].devname, verbose);
 527         }
 528
 529         if (change) {
 530                 int fd;
 531                 fd = open(devices[chosen_drive].devname, O_RDWR|O_EXCL);
 532                 if (fd < 0) {
 533                         fprintf(stderr, Name ": Could open %s for write - cannot Assemble array.\n",
 534                                 devices[chosen_drive].devname);
 535                         return 1;
 536                 }
 537                 if (st->ss->store_super(st, fd, super)) {
 538                         close(fd);
 539                         fprintf(stderr, Name ": Could not re-write superblock on %s\n",
 540                                 devices[chosen_drive].devname);
 541                         return 1;
 542                 }
 543                 close(fd);
 544         }
 545
 546         /* count number of in-sync devices according to the superblock.
 547          * We must have this number to start the array without -s or -R
 548          */
 549         req_cnt = info.array.working_disks;
 550
 551         /* Almost ready to actually *do* something */
 552         if (!old_linux) {
 553                 int rv;
 554                 if ((vers % 100) >= 1) { /* can use different versions */
 555                         mdu_array_info_t inf;
 556                         memset(&inf, 0, sizeof(inf));
 557                         inf.major_version = st->ss->major;
 558                         inf.minor_version = st->minor_version;
 559                         rv = ioctl(mdfd, SET_ARRAY_INFO, &inf);
 560                 } else
 561                         rv = ioctl(mdfd, SET_ARRAY_INFO, NULL);
 562
 563                 if (rv) {
 564                         fprintf(stderr, Name ": SET_ARRAY_INFO failed for %s: %s\n",
 565                                 mddev, strerror(errno));
 566                         return 1;
 567                 }
 568                 if (ident->bitmap_fd >= 0) {
 569                         if (ioctl(mdfd, SET_BITMAP_FILE, ident->bitmap_fd) != 0) {
 570                                 fprintf(stderr, Name ": SET_BITMAP_FILE failed.\n");
 571                                 return 1;
 572                         }
 573                 }
 574
 575                 /* First, add the raid disks, but add the chosen one last */
 576                 for (i=0; i<= bestcnt; i++) {
 577                         int j;
 578                         if (i < bestcnt) {
 579                                 j = best[i];
 580                                 if (j == chosen_drive)
 581                                         continue;
 582                         } else
 583                                 j = chosen_drive;
 584
 585                         if (j >= 0 /* && devices[j].uptodate */) {
 586                                 mdu_disk_info_t disk;
 587                                 memset(&disk, 0, sizeof(disk));
 588                                 disk.major = devices[j].major;
 589                                 disk.minor = devices[j].minor;
 590                                 if (ioctl(mdfd, ADD_NEW_DISK, &disk)!=0) {
 591                                         fprintf(stderr, Name ": failed to add %s to %s: %s\n",
 592                                                 devices[j].devname,
 593                                                 mddev,
 594                                                 strerror(errno));
 595                                         if (i < info.array.raid_disks || i == bestcnt)
 596                                                 okcnt--;
 597                                         else
 598                                                 sparecnt--;
 599                                 } else if (verbose > 0)
 600                                         fprintf(stderr, Name ": added %s to %s as %d\n",
 601                                                 devices[j].devname, mddev, devices[j].raid_disk);
 602                         } else if (verbose > 0 && i < info.array.raid_disks)
 603                                 fprintf(stderr, Name ": no uptodate device for slot %d of %s\n",
 604                                         i, mddev);
 605                 }
 606
 607                 if (runstop == 1 ||
 608                     (runstop == 0 &&
 609                      ( enough(info.array.level, info.array.raid_disks, info.array.layout, avail, okcnt) &&
 610                        (okcnt >= req_cnt || start_partial_ok)
 611                              ))) {
 612                         if (ioctl(mdfd, RUN_ARRAY, NULL)==0) {
 613                                 if (verbose >= 0) {
 614                                         fprintf(stderr, Name ": %s has been started with %d drive%s",
 615                                                 mddev, okcnt, okcnt==1?"":"s");
 616                                         if (okcnt < info.array.raid_disks)
 617                                                 fprintf(stderr, " (out of %d)", info.array.raid_disks);
 618                                         if (sparecnt)
 619                                                 fprintf(stderr, " and %d spare%s", sparecnt, sparecnt==1?"":"s");
 620                                         fprintf(stderr, ".\n");
 621                                 }
 622                                 return 0;
 623                         }
 624                         fprintf(stderr, Name ": failed to RUN_ARRAY %s: %s\n",
 625                                 mddev, strerror(errno));
 626                         return 1;
 627                 }
 628                 if (runstop == -1) {
 629                         fprintf(stderr, Name ": %s assembled from %d drive%s, but not started.\n",
 630                                 mddev, okcnt, okcnt==1?"":"s");
 631                         return 0;
 632                 }
 633                 if (verbose >= 0) {
 634                         fprintf(stderr, Name ": %s assembled from %d drive%s", mddev, okcnt, okcnt==1?"":"s");
 635                         if (sparecnt)
 636                                 fprintf(stderr, " and %d spare%s", sparecnt, sparecnt==1?"":"s");
 637                         if (!enough(info.array.level, info.array.raid_disks, info.array.layout, avail, okcnt))
 638                                 fprintf(stderr, " - not enough to start the array.\n");
 639                         else {
 640                                 if (req_cnt == info.array.raid_disks)
 641                                         fprintf(stderr, " - need all %d to start it", req_cnt);
 642                                 else
 643                                         fprintf(stderr, " - need %d of %d to start", req_cnt, info.array.raid_disks);
 644                                 fprintf(stderr, " (use --run to insist).\n");
 645                         }
 646                 }
 647                 return 1;
 648         } else {
 649                 /* The "chosen_drive" is a good choice, and if necessary, the superblock has
 650                  * been updated to point to the current locations of devices.
 651                  * so we can just start the array
 652                  */
 653                 unsigned long dev;
 654                 dev = makedev(devices[chosen_drive].major,
 655                             devices[chosen_drive].minor);
 656                 if (ioctl(mdfd, START_ARRAY, dev)) {
 657                     fprintf(stderr, Name ": Cannot start array: %s\n",
 658                             strerror(errno));
 659                 }
 660
 661         }
 662         return 0;
 663 }