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
 122         vers = md_get_version(mdfd);
 123         if (vers <= 0) {
 124                 fprintf(stderr, Name ": %s appears not to be an md device.\n", mddev);
 125                 return 1;
 126         }
 127         if (vers < 9000) {
 128                 fprintf(stderr, Name ": Assemble requires driver version 0.90.0 or later.\n"
 129                         "    Upgrade your kernel or try --build\n");
 130                 return 1;
 131         }
 132         if (get_linux_version() < 2004000)
 133                 old_linux = 1;
 134
 135         if (ioctl(mdfd, GET_ARRAY_INFO, &info.array)>=0) {
 136                 fprintf(stderr, Name ": device %s already active - cannot assemble it\n",
 137                         mddev);
 138                 return 1;
 139         }
 140         ioctl(mdfd, STOP_ARRAY, NULL); /* just incase it was started but has no content */
 141
 142         /*
 143          * If any subdevs are listed, then any that don't
 144          * match ident are discarded.  Remainder must all match and
 145          * become the array.
 146          * If no subdevs, then we scan all devices in the config file, but
 147          * there must be something in the identity
 148          */
 149
 150         if (!devlist &&
 151             ident->uuid_set == 0 &&
 152             ident->super_minor < 0 &&
 153             ident->devices == NULL) {
 154                 fprintf(stderr, Name ": No identity information available for %s - cannot assemble.\n",
 155                         mddev);
 156                 return 1;
 157         }
 158         if (devlist == NULL)
 159                 devlist = conf_get_devs(conffile);
 160         else inargv = 1;
 161
 162         tmpdev = devlist; num_devs = 0;
 163         while (tmpdev) {
 164                 num_devs++;
 165                 tmpdev = tmpdev->next;
 166         }
 167         devices = malloc(num_devs * sizeof(*devices));
 168
 169         if (!st && ident->st) st = ident->st;
 170
 171         if (verbose>0)
 172             fprintf(stderr, Name ": looking for devices for %s\n",
 173                     mddev);
 174
 175         while ( devlist) {
 176                 char *devname;
 177                 int dfd;
 178                 struct stat stb;
 179                 struct supertype *tst = st;
 180
 181                 devname = devlist->devname;
 182                 devlist = devlist->next;
 183
 184                 if (ident->devices &&
 185                     !match_oneof(ident->devices, devname)) {
 186                         if ((inargv && verbose>=0) || verbose > 0)
 187                                 fprintf(stderr, Name ": %s is not one of %s\n", devname, ident->devices);
 188                         continue;
 189                 }
 190
 191                 if (super) {
 192                         free(super);
 193                         super = NULL;
 194                 }
 195
 196                 dfd = open(devname, O_RDONLY|O_EXCL, 0);
 197                 if (dfd < 0) {
 198                         if ((inargv && verbose >= 0) || verbose > 0)
 199                                 fprintf(stderr, Name ": cannot open device %s: %s\n",
 200                                         devname, strerror(errno));
 201                 } else if (fstat(dfd, &stb)< 0) {
 202                         /* Impossible! */
 203                         fprintf(stderr, Name ": fstat failed for %s: %s\n",
 204                                 devname, strerror(errno));
 205                         close(dfd);
 206                 } else if ((stb.st_mode & S_IFMT) != S_IFBLK) {
 207                         fprintf(stderr, Name ": %s is not a block device.\n",
 208                                 devname);
 209                         close(dfd);
 210                 } else if (!tst && (tst = guess_super(dfd)) == NULL) {
 211                         if ((inargv && verbose >= 0) || verbose > 0)
 212                                 fprintf(stderr, Name ": no recogniseable superblock\n");
 213                 } else if (tst->ss->load_super(tst,dfd, &super, NULL)) {
 214                         if ((inargv && verbose >= 0) || verbose > 0)
 215                                 fprintf( stderr, Name ": no RAID superblock on %s\n",
 216                                          devname);
 217                         close(dfd);
 218                 } else {
 219                         tst->ss->getinfo_super(&info, &ident2, super);
 220                         close(dfd);
 221                 }
 222
 223                 if (ident->uuid_set &&
 224                     (!super || same_uuid(info.uuid, ident->uuid, tst->ss->swapuuid)==0)) {
 225                         if ((inargv && verbose >= 0) || verbose > 0)
 226                                 fprintf(stderr, Name ": %s has wrong uuid.\n",
 227                                         devname);
 228                         continue;
 229                 }
 230                 if (ident->name[0] &&
 231                     (!super || strncmp(ident2.name, ident->name, 32)!=0)) {
 232                         if ((inargv && verbose >= 0) || verbose > 0)
 233                                 fprintf(stderr, Name ": %s has wrong name.\n",
 234                                         devname);
 235                         continue;
 236                 }
 237                 if (ident->super_minor != UnSet &&
 238                     (!super || ident->super_minor != info.array.md_minor)) {
 239                         if ((inargv && verbose >= 0) || verbose > 0)
 240                                 fprintf(stderr, Name ": %s has wrong super-minor.\n",
 241                                         devname);
 242                         continue;
 243                 }
 244                 if (ident->level != UnSet &&
 245                     (!super|| ident->level != info.array.level)) {
 246                         if ((inargv && verbose >= 0) || verbose > 0)
 247                                 fprintf(stderr, Name ": %s has wrong raid level.\n",
 248                                         devname);
 249                         continue;
 250                 }
 251                 if (ident->raid_disks != UnSet &&
 252                     (!super || ident->raid_disks!= info.array.raid_disks)) {
 253                         if ((inargv && verbose >= 0) || verbose > 0)
 254                                 fprintf(stderr, Name ": %s requires wrong number of drives.\n",
 255                                         devname);
 256                         continue;
 257                 }
 258
 259                 /* If we are this far, then we are commited to this device.
 260                  * If the super_block doesn't exist, or doesn't match others,
 261                  * then we cannot continue
 262                  */
 263
 264                 if (!super) {
 265                         fprintf(stderr, Name ": %s has no superblock - assembly aborted\n",
 266                                 devname);
 267                         free(first_super);
 268                         return 1;
 269                 }
 270                 st = tst; /* commit to this format, if haven't already */
 271                 if (st->ss->compare_super(&first_super, super)) {
 272                         fprintf(stderr, Name ": superblock on %s doesn't match others - assembly aborted\n",
 273                                 devname);
 274                         free(super);
 275                         free(first_super);
 276                         return 1;
 277                 }
 278
 279                 /* looks like a good enough match to update the super block if needed */
 280                 if (update) {
 281                         /* prepare useful information in info structures */
 282                         struct stat stb2;
 283                         fstat(mdfd, &stb2);
 284                         info.array.md_minor = minor(stb2.st_rdev);
 285
 286                         st->ss->update_super(&info, super, update, devname, verbose);
 287
 288                         dfd = open(devname, O_RDWR|O_EXCL, 0);
 289                         if (dfd < 0)
 290                                 fprintf(stderr, Name ": Cannot open %s for superblock update\n",
 291                                         devname);
 292                         else if (st->ss->store_super(st, dfd, super))
 293                                 fprintf(stderr, Name ": Could not re-write superblock on %s.\n",
 294                                         devname);
 295                         if (dfd >= 0)
 296                                 close(dfd);
 297                 }
 298
 299                 if (verbose > 0)
 300                         fprintf(stderr, Name ": %s is identified as a member of %s, slot %d.\n",
 301                                 devname, mddev, info.disk.raid_disk);
 302                 devices[devcnt].devname = devname;
 303                 devices[devcnt].major = major(stb.st_rdev);
 304                 devices[devcnt].minor = minor(stb.st_rdev);
 305                 devices[devcnt].oldmajor = info.disk.major;
 306                 devices[devcnt].oldminor = info.disk.minor;
 307                 devices[devcnt].events = info.events;
 308                 devices[devcnt].raid_disk = info.disk.raid_disk;
 309                 devices[devcnt].disk_nr = info.disk.number;
 310                 devices[devcnt].uptodate = 0;
 311                 devices[devcnt].state = info.disk.state;
 312                 if (most_recent < devcnt) {
 313                         if (devices[devcnt].events
 314                             > devices[most_recent].events)
 315                                 most_recent = devcnt;
 316                 }
 317                 if (info.array.level == -4)
 318                         /* with multipath, the raid_disk from the superblock is meaningless */
 319                         i = devcnt;
 320                 else
 321                         i = devices[devcnt].raid_disk;
 322                 if (i < 10000) {
 323                         if (i >= bestcnt) {
 324                                 unsigned int newbestcnt = i+10;
 325                                 int *newbest = malloc(sizeof(int)*newbestcnt);
 326                                 unsigned int c;
 327                                 for (c=0; c < newbestcnt; c++)
 328                                         if (c < bestcnt)
 329                                                 newbest[c] = best[c];
 330                                         else
 331                                                 newbest[c] = -1;
 332                                 if (best)free(best);
 333                                 best = newbest;
 334                                 bestcnt = newbestcnt;
 335                         }
 336                         if (best[i] == -1
 337                             || devices[best[i]].events < devices[devcnt].events)
 338                                 best[i] = devcnt;
 339                 }
 340                 devcnt++;
 341         }
 342
 343         if (super)
 344                 free(super);
 345         super = NULL;
 346
 347         if (update && strcmp(update, "byteorder")==0)
 348                 st->minor_version = 90;
 349
 350         if (devcnt == 0) {
 351                 fprintf(stderr, Name ": no devices found for %s\n",
 352                         mddev);
 353                 free(first_super);
 354                 return 1;
 355         }
 356
 357         st->ss->getinfo_super(&info, &ident2, first_super);
 358
 359         /* now we have some devices that might be suitable.
 360          * I wonder how many
 361          */
 362         okcnt = 0;
 363         sparecnt=0;
 364         for (i=0; i< bestcnt ;i++) {
 365                 int j = best[i];
 366                 int event_margin = !force;
 367                 if (j < 0) continue;
 368                 /* note: we ignore error flags in multipath arrays
 369                  * as they don't make sense
 370                  */
 371                 if (info.array.level != -4)
 372                         if (!(devices[j].state & (1<<MD_DISK_SYNC))) {
 373                                 if (!(devices[j].state & (1<<MD_DISK_FAULTY)))
 374                                         sparecnt++;
 375                                 continue;
 376                         }
 377                 if (devices[j].events+event_margin >=
 378                     devices[most_recent].events) {
 379                         devices[j].uptodate = 1;
 380                         if (i < info.array.raid_disks)
 381                                 okcnt++;
 382                         else
 383                                 sparecnt++;
 384                 }
 385         }
 386         while (force && !enough(info.array.level, info.array.raid_disks, okcnt)) {
 387                 /* Choose the newest best drive which is
 388                  * not up-to-date, update the superblock
 389                  * and add it.
 390                  */
 391                 int fd;
 392                 chosen_drive = -1;
 393                 for (i=0; i<info.array.raid_disks && i < bestcnt; i++) {
 394                         int j = best[i];
 395                         if (j>=0 &&
 396                             !devices[j].uptodate &&
 397                             devices[j].events > 0 &&
 398                             (chosen_drive < 0 ||
 399                              devices[j].events > devices[chosen_drive].events))
 400                                 chosen_drive = j;
 401                 }
 402                 if (chosen_drive < 0)
 403                         break;
 404                 if (verbose >= 0)
 405                         fprintf(stderr, Name ": forcing event count in %s(%d) from %d upto %d\n",
 406                                 devices[chosen_drive].devname, devices[chosen_drive].raid_disk,
 407                                 (int)(devices[chosen_drive].events),
 408                                 (int)(devices[most_recent].events));
 409                 fd = open(devices[chosen_drive].devname, O_RDWR|O_EXCL);
 410                 if (fd < 0) {
 411                         fprintf(stderr, Name ": Couldn't open %s for write - not updating\n",
 412                                 devices[chosen_drive].devname);
 413                         devices[chosen_drive].events = 0;
 414                         continue;
 415                 }
 416                 if (st->ss->load_super(st,fd, &super, NULL)) {
 417                         close(fd);
 418                         fprintf(stderr, Name ": RAID superblock disappeared from %s - not updating.\n",
 419                                 devices[chosen_drive].devname);
 420                         devices[chosen_drive].events = 0;
 421                         continue;
 422                 }
 423                 info.events = devices[most_recent].events;
 424                 st->ss->update_super(&info, super, "force", devices[chosen_drive].devname, verbose);
 425
 426                 if (st->ss->store_super(st, fd, super)) {
 427                         close(fd);
 428                         fprintf(stderr, Name ": Could not re-write superblock on %s\n",
 429                                 devices[chosen_drive].devname);
 430                         devices[chosen_drive].events = 0;
 431                         free(super);
 432                         continue;
 433                 }
 434                 close(fd);
 435                 devices[chosen_drive].events = devices[most_recent].events;
 436                 devices[chosen_drive].uptodate = 1;
 437                 okcnt++;
 438                 free(super);
 439         }
 440
 441         /* Now we want to look at the superblock which the kernel will base things on
 442          * and compare the devices that we think are working with the devices that the
 443          * superblock thinks are working.
 444          * If there are differences and --force is given, then update this chosen
 445          * superblock.
 446          */
 447         chosen_drive = -1;
 448         super = NULL;
 449         for (i=0; chosen_drive < 0 && i<bestcnt; i++) {
 450                 int j = best[i];
 451                 int fd;
 452
 453                 if (j<0)
 454                         continue;
 455                 if (!devices[j].uptodate)
 456                         continue;
 457                 chosen_drive = j;
 458                 if ((fd=open(devices[j].devname, O_RDONLY|O_EXCL))< 0) {
 459                         fprintf(stderr, Name ": Cannot open %s: %s\n",
 460                                 devices[j].devname, strerror(errno));
 461                         return 1;
 462                 }
 463                 if (st->ss->load_super(st,fd, &super, NULL)) {
 464                         close(fd);
 465                         fprintf(stderr, Name ": RAID superblock has disappeared from %s\n",
 466                                 devices[j].devname);
 467                         return 1;
 468                 }
 469                 close(fd);
 470         }
 471         if (super == NULL) {
 472                 fprintf(stderr, Name ": No suitable drives found for %s\n", mddev);
 473                 return 1;
 474         }
 475         st->ss->getinfo_super(&info, &ident2, super);
 476         for (i=0; i<bestcnt; i++) {
 477                 int j = best[i];
 478                 unsigned int desired_state;
 479
 480                 if (i < info.array.raid_disks)
 481                         desired_state = (1<<MD_DISK_ACTIVE) | (1<<MD_DISK_SYNC);
 482                 else
 483                         desired_state = 0;
 484
 485                 if (j<0)
 486                         continue;
 487                 if (!devices[j].uptodate)
 488                         continue;
 489                 info.disk.number = devices[j].disk_nr;
 490                 info.disk.raid_disk = i;
 491                 info.disk.state = desired_state;
 492
 493                 if (devices[j].uptodate &&
 494                     st->ss->update_super(&info, super, "assemble", NULL, verbose)) {
 495                         if (force) {
 496                                 if (verbose >= 0)
 497                                         fprintf(stderr, Name ": "
 498                                                 "clearing FAULTY flag for device %d in %s for %s\n",
 499                                                 j, mddev, devices[j].devname);
 500                                 change = 1;
 501                         } else {
 502                                 if (verbose >= -1)
 503                                         fprintf(stderr, Name ": "
 504                                                 "device %d in %s has wrong state in superblock, but %s seems ok\n",
 505                                                 i, mddev, devices[j].devname);
 506                         }
 507                 }
 508 #if 0
 509                 if (!devices[j].uptodate &&
 510                     !(super.disks[i].state & (1 << MD_DISK_FAULTY))) {
 511                         fprintf(stderr, Name ": devices %d of %s is not marked FAULTY in superblock, but cannot be found\n",
 512                                 i, mddev);
 513                 }
 514 #endif
 515         }
 516         if (force && okcnt == info.array.raid_disks-1) {
 517                 /* FIXME check event count */
 518                 change += st->ss->update_super(&info, super, "force",
 519                                         devices[chosen_drive].devname, verbose);
 520         }
 521
 522         if (change) {
 523                 int fd;
 524                 fd = open(devices[chosen_drive].devname, O_RDWR|O_EXCL);
 525                 if (fd < 0) {
 526                         fprintf(stderr, Name ": Could open %s for write - cannot Assemble array.\n",
 527                                 devices[chosen_drive].devname);
 528                         return 1;
 529                 }
 530                 if (st->ss->store_super(st, fd, super)) {
 531                         close(fd);
 532                         fprintf(stderr, Name ": Could not re-write superblock on %s\n",
 533                                 devices[chosen_drive].devname);
 534                         return 1;
 535                 }
 536                 close(fd);
 537         }
 538
 539         /* count number of in-sync devices according to the superblock.
 540          * We must have this number to start the array without -s or -R
 541          */
 542         req_cnt = info.array.working_disks;
 543
 544         /* Almost ready to actually *do* something */
 545         if (!old_linux) {
 546                 int rv;
 547                 if ((vers % 100) >= 1) { /* can use different versions */
 548                         mdu_array_info_t inf;
 549                         memset(&inf, 0, sizeof(inf));
 550                         inf.major_version = st->ss->major;
 551                         inf.minor_version = st->minor_version;
 552                         rv = ioctl(mdfd, SET_ARRAY_INFO, &inf);
 553                 } else
 554                         rv = ioctl(mdfd, SET_ARRAY_INFO, NULL);
 555
 556                 if (rv) {
 557                         fprintf(stderr, Name ": SET_ARRAY_INFO failed for %s: %s\n",
 558                                 mddev, strerror(errno));
 559                         return 1;
 560                 }
 561                 if (ident->bitmap_fd >= 0) {
 562                         if (ioctl(mdfd, SET_BITMAP_FILE, ident->bitmap_fd) != 0) {
 563                                 fprintf(stderr, Name ": SET_BITMAP_FILE failed.\n");
 564                                 return 1;
 565                         }
 566                 }
 567
 568                 /* First, add the raid disks, but add the chosen one last */
 569                 for (i=0; i<= bestcnt; i++) {
 570                         int j;
 571                         if (i < bestcnt) {
 572                                 j = best[i];
 573                                 if (j == chosen_drive)
 574                                         continue;
 575                         } else
 576                                 j = chosen_drive;
 577
 578                         if (j >= 0 /* && devices[j].uptodate */) {
 579                                 mdu_disk_info_t disk;
 580                                 memset(&disk, 0, sizeof(disk));
 581                                 disk.major = devices[j].major;
 582                                 disk.minor = devices[j].minor;
 583                                 if (ioctl(mdfd, ADD_NEW_DISK, &disk)!=0) {
 584                                         fprintf(stderr, Name ": failed to add %s to %s: %s\n",
 585                                                 devices[j].devname,
 586                                                 mddev,
 587                                                 strerror(errno));
 588                                         if (i < info.array.raid_disks || i == bestcnt)
 589                                                 okcnt--;
 590                                         else
 591                                                 sparecnt--;
 592                                 } else if (verbose > 0)
 593                                         fprintf(stderr, Name ": added %s to %s as %d\n",
 594                                                 devices[j].devname, mddev, devices[j].raid_disk);
 595                         } else if (verbose > 0 && i < info.array.raid_disks)
 596                                 fprintf(stderr, Name ": no uptodate device for slot %d of %s\n",
 597                                         i, mddev);
 598                 }
 599
 600                 if (runstop == 1 ||
 601                     (runstop == 0 &&
 602                      ( enough(info.array.level, info.array.raid_disks, okcnt) &&
 603                        (okcnt >= req_cnt || start_partial_ok)
 604                              ))) {
 605                         if (ioctl(mdfd, RUN_ARRAY, NULL)==0) {
 606                                 if (verbose >= 0) {
 607                                         fprintf(stderr, Name ": %s has been started with %d drive%s",
 608                                                 mddev, okcnt, okcnt==1?"":"s");
 609                                         if (okcnt < info.array.raid_disks)
 610                                                 fprintf(stderr, " (out of %d)", info.array.raid_disks);
 611                                         if (sparecnt)
 612                                                 fprintf(stderr, " and %d spare%s", sparecnt, sparecnt==1?"":"s");
 613                                         fprintf(stderr, ".\n");
 614                                 }
 615                                 return 0;
 616                         }
 617                         fprintf(stderr, Name ": failed to RUN_ARRAY %s: %s\n",
 618                                 mddev, strerror(errno));
 619                         return 1;
 620                 }
 621                 if (runstop == -1) {
 622                         fprintf(stderr, Name ": %s assembled from %d drive%s, but not started.\n",
 623                                 mddev, okcnt, okcnt==1?"":"s");
 624                         return 0;
 625                 }
 626                 if (verbose >= 0) {
 627                         fprintf(stderr, Name ": %s assembled from %d drive%s", mddev, okcnt, okcnt==1?"":"s");
 628                         if (sparecnt)
 629                                 fprintf(stderr, " and %d spare%s", sparecnt, sparecnt==1?"":"s");
 630                         if (!enough(info.array.level, info.array.raid_disks, okcnt))
 631                                 fprintf(stderr, " - not enough to start the array.\n");
 632                         else {
 633                                 if (req_cnt == info.array.raid_disks)
 634                                         fprintf(stderr, " - need all %d to start it", req_cnt);
 635                                 else
 636                                         fprintf(stderr, " - need %d of %d to start", req_cnt, info.array.raid_disks);
 637                                 fprintf(stderr, " (use --run to insist).\n");
 638                         }
 639                 }
 640                 return 1;
 641         } else {
 642                 /* The "chosen_drive" is a good choice, and if necessary, the superblock has
 643                  * been updated to point to the current locations of devices.
 644                  * so we can just start the array
 645                  */
 646                 unsigned long dev;
 647                 dev = makedev(devices[chosen_drive].major,
 648                             devices[chosen_drive].minor);
 649                 if (ioctl(mdfd, START_ARRAY, dev)) {
 650                     fprintf(stderr, Name ": Cannot start array: %s\n",
 651                             strerror(errno));
 652                 }
 653
 654         }
 655         return 0;
 656 }