super1.c

   1 /*
   2  * mdadm - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001-2004 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 #include "asm/byteorder.h"
  33 /*
  34  * The version-1 superblock :
  35  * All numeric fields are little-endian.
  36  *
  37  * total size: 256 bytes plus 2 per device.
  38  *  1K allows 384 devices.
  39  */
  40 struct mdp_superblock_1 {
  41         /* constant array information - 128 bytes */
  42         __u32   magic;          /* MD_SB_MAGIC: 0xa92b4efc - little endian */
  43         __u32   major_version;  /* 1 */
  44         __u32   feature_map;    /* 0 for now */
  45         __u32   pad0;           /* always set to 0 when writing */
  46
  47         __u8    set_uuid[16];   /* user-space generated. */
  48         char    set_name[32];   /* set and interpreted by user-space */
  49
  50         __u64   ctime;          /* lo 40 bits are seconds, top 24 are microseconds or 0*/
  51         __u32   level;          /* -4 (multipath), -1 (linear), 0,1,4,5 */
  52         __u32   layout;         /* only for raid5 currently */
  53         __u64   size;           /* used size of component devices, in 512byte sectors */
  54
  55         __u32   chunksize;      /* in 512byte sectors */
  56         __u32   raid_disks;
  57         __u8    pad1[128-96];   /* set to 0 when written */
  58
  59         /* constant this-device information - 64 bytes */
  60         __u64   data_offset;    /* sector start of data, often 0 */
  61         __u64   data_size;      /* sectors in this device that can be used for data */
  62         __u64   super_offset;   /* sector start of this superblock */
  63         __u64   recovery_offset;/* sectors before this offset (from data_offset) have been recovered */
  64         __u32   dev_number;     /* permanent identifier of this  device - not role in raid */
  65         __u32   cnt_corrected_read; /* number of read errors that were corrected by re-writing */
  66         __u8    device_uuid[16]; /* user-space setable, ignored by kernel */
  67         __u8    pad2[64-56];    /* set to 0 when writing */
  68
  69         /* array state information - 64 bytes */
  70         __u64   utime;          /* 40 bits second, 24 btes microseconds */
  71         __u64   events;         /* incremented when superblock updated */
  72         __u64   resync_offset;  /* data before this offset (from data_offset) known to be in sync */
  73         __u32   sb_csum;        /* checksum upto devs[max_dev] */
  74         __u32   max_dev;        /* size of devs[] array to consider */
  75         __u8    pad3[64-32];    /* set to 0 when writing */
  76
  77         /* device state information. Indexed by dev_number.
  78          * 2 bytes per device
  79          * Note there are no per-device state flags. State information is rolled
  80          * into the 'roles' value.  If a device is spare or faulty, then it doesn't
  81          * have a meaningful role.
  82          */
  83         __u16   dev_roles[0];   /* role in array, or 0xffff for a spare, or 0xfffe for faulty */
  84 };
  85
  86 #ifndef offsetof
  87 #define offsetof(t,f) ((int)&(((t*)0)->f))
  88 #endif
  89 static unsigned int calc_sb_1_csum(struct mdp_superblock_1 * sb)
  90 {
  91         unsigned int disk_csum, csum;
  92         unsigned long long newcsum;
  93         int size = sizeof(*sb) + __le32_to_cpu(sb->max_dev)*2;
  94         unsigned int *isuper = (unsigned int*)sb;
  95         int i;
  96
  97 /* make sure I can count... */
  98         if (offsetof(struct mdp_superblock_1,data_offset) != 128 ||
  99             offsetof(struct mdp_superblock_1, utime) != 192 ||
 100             sizeof(struct mdp_superblock_1) != 256) {
 101                 fprintf(stderr, "WARNING - superblock isn't sized correctly\n");
 102         }
 103
 104         disk_csum = sb->sb_csum;
 105         sb->sb_csum = 0;
 106         newcsum = 0;
 107         for (i=0; size>=4; size -= 4 )
 108                 newcsum += __le32_to_cpu(*isuper++);
 109
 110         if (size == 2)
 111                 newcsum += __le16_to_cpu(*(unsigned short*) isuper);
 112
 113         csum = (newcsum & 0xffffffff) + (newcsum >> 32);
 114         sb->sb_csum = disk_csum;
 115         return csum;
 116 }
 117
 118
 119 static void examine_super1(void *sbv)
 120 {
 121         struct mdp_superblock_1 *sb = sbv;
 122         time_t atime;
 123         int d;
 124         int spares, faulty;
 125         int i;
 126         char *c;
 127
 128         printf("          Magic : %08x\n", __le32_to_cpu(sb->magic));
 129         printf("        Version : %02d.%02d\n", 1, __le32_to_cpu(sb->feature_map));
 130         printf("     Array UUID : ");
 131         for (i=0; i<16; i++) {
 132                 printf("%02x", sb->set_uuid[i]);
 133                 if ((i&3)==0 && i != 0) printf(":");
 134         }
 135         printf("\n");
 136         printf("           Name : %.32s\n", sb->set_name);
 137
 138         atime = __le64_to_cpu(sb->ctime) & 0xFFFFFFFFFFULL;
 139         printf("  Creation Time : %.24s\n", ctime(&atime));
 140         c=map_num(pers, __le32_to_cpu(sb->level));
 141         printf("     Raid Level : %s\n", c?c:"-unknown-");
 142         printf("   Raid Devices : %d\n", __le32_to_cpu(sb->raid_disks));
 143         printf("\n");
 144         printf("    Device Size : %llu%s\n", (unsigned long long)sb->data_size, human_size(sb->data_size<<9));
 145         if (sb->data_offset)
 146                 printf("    Data Offset : %llu sectors\n", (unsigned long long)__le64_to_cpu(sb->data_offset));
 147         if (sb->super_offset)
 148                 printf("   Super Offset : %llu sectors\n", (unsigned long long)__le64_to_cpu(sb->super_offset));
 149         printf("          State : %s\n", (__le64_to_cpu(sb->resync_offset)+1)? "active":"clean");
 150         printf("    Device UUID : ");
 151         for (i=0; i<16; i++) {
 152                 printf("%02x", sb->set_uuid[i]);
 153                 if ((i&3)==0 && i != 0) printf(":");
 154         }
 155         printf("\n");
 156
 157         atime = __le64_to_cpu(sb->utime) & 0xFFFFFFFFFFULL;
 158         printf("    Update Time : %.24s\n", ctime(&atime));
 159
 160         if (calc_sb_1_csum(sb) == sb->sb_csum)
 161                 printf("       Checksum : %x - correct\n", __le32_to_cpu(sb->sb_csum));
 162         else
 163                 printf("       Checksum : %x - expected %x\n", __le32_to_cpu(sb->sb_csum),
 164                        __le32_to_cpu(calc_sb_1_csum(sb)));
 165         printf("         Events : %llu\n", (unsigned long long)__le64_to_cpu(sb->events));
 166         printf("\n");
 167         if (__le32_to_cpu(sb->level) == 5) {
 168                 c = map_num(r5layout, __le32_to_cpu(sb->layout));
 169                 printf("         Layout : %s\n", c?c:"-unknown-");
 170         }
 171         switch(__le32_to_cpu(sb->level)) {
 172         case 0:
 173         case 4:
 174         case 5:
 175                 printf("     Chunk Size : %dK\n", __le32_to_cpu(sb->chunksize/2));
 176                 break;
 177         case -1:
 178                 printf("       Rounding : %dK\n", __le32_to_cpu(sb->chunksize/2));
 179                 break;
 180         default: break;
 181         }
 182         printf("\n");
 183         printf("   Array State : ");
 184         for (d=0; d<__le32_to_cpu(sb->raid_disks); d++) {
 185                 int cnt = 0;
 186                 int me = 0;
 187                 int i;
 188                 for (i=0; i< __le32_to_cpu(sb->max_dev); i++) {
 189                         int role = __le16_to_cpu(sb->dev_roles[i]);
 190                         if (role == d) {
 191                                 if (i == __le32_to_cpu(sb->dev_number))
 192                                         me = 1;
 193                                 cnt++;
 194                         }
 195                 }
 196                 if (cnt > 1) printf("?");
 197                 else if (cnt == 1 && me) printf("U");
 198                 else if (cnt == 1) printf("u");
 199                 else printf ("_");
 200         }
 201         spares = faulty = 0;
 202         for (i=0; i< __le32_to_cpu(sb->max_dev); i++) {
 203                 int role = __le16_to_cpu(sb->dev_roles[i]);
 204                 switch (role) {
 205                 case 0xFFFF: spares++; break;
 206                 case 0xFFFE: faulty++;
 207                 }
 208         }
 209         if (spares) printf(" %d spares", spares);
 210         if (faulty) printf(" %d failed", faulty);
 211         printf("\n");
 212 }
 213
 214
 215 static void brief_examine_super1(void *sbv)
 216 {
 217         struct mdp_superblock_1 *sb = sbv;
 218         int i;
 219
 220         char *c=map_num(pers, __le32_to_cpu(sb->level));
 221
 222         printf("ARRAY /dev/?? level=%s metadata=1 num-devices=%d UUID=",
 223                c?c:"-unknown-", sb->raid_disks);
 224         for (i=0; i<16; i++) {
 225                 printf("%02x", sb->set_uuid[i]);
 226                 if ((i&3)==0 && i != 0) printf(":");
 227         }
 228         printf("\n");
 229 }
 230
 231 static void detail_super1(void *sbv)
 232 {
 233         struct mdp_superblock_1 *sb = sbv;
 234         int i;
 235
 236         printf("           UUID : ");
 237         for (i=0; i<16; i++) {
 238                 printf("%02x", sb->set_uuid[i]);
 239                 if ((i&3)==0 && i != 0) printf(":");
 240         }
 241         printf("\n         Events : %llu\n\n", (unsigned long long)__le64_to_cpu(sb->events));
 242 }
 243
 244 static void brief_detail_super1(void *sbv)
 245 {
 246         struct mdp_superblock_1 *sb = sbv;
 247         int i;
 248
 249         printf(" UUID=");
 250         for (i=0; i<16; i++) {
 251                 printf("%02x", sb->set_uuid[i]);
 252                 if ((i&3)==0 && i != 0) printf(":");
 253         }
 254 }
 255
 256 static void uuid_from_super1(int uuid[4], void * sbv)
 257 {
 258         struct mdp_superblock_1 *super = sbv;
 259         char *cuuid = (char*)uuid;
 260         int i;
 261         for (i=0; i<16; i++)
 262                 cuuid[i] = super->set_uuid[i];
 263 }
 264
 265 static void getinfo_super1(struct mdinfo *info, void *sbv)
 266 {
 267         struct mdp_superblock_1 *sb = sbv;
 268         int working = 0;
 269         int i;
 270         int role;
 271
 272         info->array.major_version = 1;
 273         info->array.minor_version = __le32_to_cpu(sb->feature_map);
 274         info->array.patch_version = 0;
 275         info->array.raid_disks = __le32_to_cpu(sb->raid_disks);
 276         info->array.level = __le32_to_cpu(sb->level);
 277         info->array.md_minor = -1;
 278         info->array.ctime = __le64_to_cpu(sb->ctime);
 279
 280         info->disk.major = 0;
 281         info->disk.minor = 0;
 282
 283         if (__le32_to_cpu(sb->dev_number) >= __le32_to_cpu(sb->max_dev) ||
 284             __le32_to_cpu(sb->max_dev) > 512)
 285                 role = 0xfffe;
 286         else
 287                 role = __le16_to_cpu(sb->dev_roles[__le32_to_cpu(sb->dev_number)]);
 288
 289         info->disk.raid_disk = -1;
 290         switch(role) {
 291         case 0xFFFF:
 292                 info->disk.state = 2; /* spare: ACTIVE, not sync, not faulty */
 293                 break;
 294         case 0xFFFE:
 295                 info->disk.state = 1; /* faulty */
 296                 break;
 297         default:
 298                 info->disk.state = 6; /* active and in sync */
 299                 info->disk.raid_disk = role;
 300         }
 301         info->events = __le64_to_cpu(sb->events);
 302
 303         memcpy(info->uuid, sb->set_uuid, 16);
 304
 305         for (i=0; i< __le32_to_cpu(sb->max_dev); i++) {
 306                 role = __le16_to_cpu(sb->dev_roles[i]);
 307                 if (role == 0xFFFF || role < info->array.raid_disks)
 308                         working++;
 309         }
 310
 311         info->array.working_disks = working;
 312 }
 313
 314 static int update_super1(struct mdinfo *info, void *sbv, char *update, char *devname, int verbose)
 315 {
 316         int rv = 0;
 317         struct mdp_superblock_1 *sb = sbv;
 318
 319         if (strcmp(update, "force")==0) {
 320                 sb->events = __cpu_to_le32(info->events);
 321                 switch(__le32_to_cpu(sb->level)) {
 322                 case 5: case 4: case 6:
 323                         /* need to force clean */
 324                         sb->resync_offset = ~0ULL;
 325                 }
 326         }
 327         if (strcmp(update, "assemble")==0) {
 328                 int d = info->disk.number;
 329                 int want;
 330                 if (info->disk.state == 6)
 331                         want = __cpu_to_le32(info->disk.raid_disk);
 332                 else
 333                         want = 0xFFFF;
 334                 if (sb->dev_roles[d] != want) {
 335                         sb->dev_roles[d] = want;
 336                         rv = 1;
 337                 }
 338         }
 339 #if 0
 340         if (strcmp(update, "newdev") == 0) {
 341                 int d = info->disk.number;
 342                 memset(&sb->disks[d], 0, sizeof(sb->disks[d]));
 343                 sb->disks[d].number = d;
 344                 sb->disks[d].major = info->disk.major;
 345                 sb->disks[d].minor = info->disk.minor;
 346                 sb->disks[d].raid_disk = info->disk.raid_disk;
 347                 sb->disks[d].state = info->disk.state;
 348                 sb->this_disk = sb->disks[d];
 349         }
 350 #endif
 351         if (strcmp(update, "grow") == 0) {
 352                 sb->raid_disks = __cpu_to_le32(info->array.raid_disks);
 353                 /* FIXME */
 354         }
 355         if (strcmp(update, "resync") == 0) {
 356                 /* make sure resync happens */
 357                 sb->resync_offset = ~0ULL;
 358         }
 359
 360         sb->sb_csum = calc_sb_1_csum(sb);
 361         return rv;
 362 }
 363
 364
 365 static __u64 event_super1(void *sbv)
 366 {
 367         struct mdp_superblock_1 *sb = sbv;
 368         return __le64_to_cpu(sb->events);
 369 }
 370
 371 static int init_super1(void **sbp, mdu_array_info_t *info)
 372 {
 373         struct mdp_superblock_1 *sb = malloc(1024);
 374         int spares;
 375         memset(sb, 0, 1024);
 376
 377         if (info->major_version == -1)
 378                 /* zeroing superblock */
 379                 return 0;
 380
 381         spares = info->working_disks - info->active_disks;
 382         if (info->raid_disks + spares  > 384) {
 383                 fprintf(stderr, Name ": too many devices requested: %d+%d > %d\n",
 384                         info->raid_disks , spares, 384);
 385                 return 0;
 386         }
 387
 388
 389         sb->magic = __cpu_to_le32(MD_SB_MAGIC);
 390         sb->major_version = __cpu_to_le32(1);
 391         sb->feature_map = 0;
 392         sb->pad0 = 0;
 393         *(__u32*)(sb->set_uuid) = random();
 394         *(__u32*)(sb->set_uuid+4) = random();
 395         *(__u32*)(sb->set_uuid+8) = random();
 396         *(__u32*)(sb->set_uuid+12) = random();
 397
 398         /* FIXME name */
 399
 400         sb->ctime = __cpu_to_le64((unsigned long long)time(0));
 401         sb->level = __cpu_to_le32(info->level);
 402         sb->layout = __cpu_to_le32(info->level);
 403         sb->size = __cpu_to_le64(info->size*2ULL);
 404         sb->chunksize = __cpu_to_le32(info->chunk_size>>9);
 405         sb->raid_disks = __cpu_to_le32(info->raid_disks);
 406
 407         sb->data_offset = __cpu_to_le64(0);
 408         sb->data_size = __cpu_to_le64(0);
 409         sb->super_offset = __cpu_to_le64(0);
 410         sb->recovery_offset = __cpu_to_le64(0);
 411
 412         sb->utime = sb->ctime;
 413         sb->events = __cpu_to_le64(1);
 414         if (info->state & MD_SB_CLEAN)
 415                 sb->resync_offset = ~0ULL;
 416         else
 417                 sb->resync_offset = 0;
 418         sb->max_dev = __cpu_to_le32((1024- sizeof(struct mdp_superblock_1))/
 419                                     sizeof(sb->dev_roles[0]));
 420         memset(sb->pad3, 0, sizeof(sb->pad3));
 421
 422         memset(sb->dev_roles, 0xff, 1024 - sizeof(struct mdp_superblock_1));
 423
 424         *sbp = sb;
 425         return 1;
 426 }
 427
 428 /* Add a device to the superblock being created */
 429 static void add_to_super1(void *sbv, mdu_disk_info_t *dk)
 430 {
 431         struct mdp_superblock_1 *sb = sbv;
 432         __u16 *rp = sb->dev_roles + dk->number;
 433         if (dk->state == 6) /* active, sync */
 434                 *rp = __cpu_to_le16(dk->raid_disk);
 435         else if (dk->state == 2) /* active -> spare */
 436                 *rp = 0xffff;
 437         else
 438                 *rp = 0xfffe;
 439 }
 440
 441 static int store_super1(int fd, void *sbv)
 442 {
 443         struct mdp_superblock_1 *sb = sbv;
 444         long long sb_offset;
 445         int sbsize;
 446
 447
 448         sb_offset = __le64_to_cpu(sb->super_offset) << 9;
 449
 450         if (lseek64(fd, sb_offset, 0)< 0LL)
 451                 return 3;
 452
 453         sbsize = sizeof(*sb) + 2 * __le32_to_cpu(sb->max_dev);
 454
 455         if (write(fd, sb, sbsize) != sbsize)
 456                 return 4;
 457
 458         fsync(fd);
 459         return 0;
 460 }
 461
 462 static int load_super1(struct supertype *st, int fd, void **sbp, char *devname);
 463
 464 static int write_init_super1(struct supertype *st, void *sbv, mdu_disk_info_t *dinfo, char *devname)
 465 {
 466         struct mdp_superblock_1 *sb = sbv;
 467         struct mdp_superblock_1 *refsb = NULL;
 468         int fd = open(devname, O_RDWR | O_EXCL);
 469         int rv;
 470
 471         long size;
 472         long long sb_offset;
 473
 474
 475         if (fd < 0) {
 476                 fprintf(stderr, Name ": Failed to open %s to write superblock\n",
 477                         devname);
 478                 return -1;
 479         }
 480
 481         sb->dev_number = __cpu_to_le32(dinfo->number);
 482
 483         *(__u32*)(sb->device_uuid) = random();
 484         *(__u32*)(sb->device_uuid+4) = random();
 485         *(__u32*)(sb->device_uuid+8) = random();
 486         *(__u32*)(sb->device_uuid+12) = random();
 487         sb->events = 0;
 488
 489         if (load_super1(st, fd, (void**)&refsb, NULL)==0) {
 490                 memcpy(sb->device_uuid, refsb->device_uuid, 16);
 491                 if (memcmp(sb->set_uuid, refsb->set_uuid, 16)==0) {
 492                         /* same array, so preserve events and dev_number */
 493                         sb->events = refsb->events;
 494                         sb->dev_number = refsb->dev_number;
 495                 }
 496                 free(refsb);
 497         }
 498
 499         if (ioctl(fd, BLKGETSIZE, &size)) {
 500                 close(fd);
 501                 return 1;
 502         }
 503
 504         if (size < 24) {
 505                 close(fd);
 506                 return 2;
 507         }
 508
 509
 510         /*
 511          * Calculate the position of the superblock.
 512          * It is always aligned to a 4K boundary and
 513          * depending on minor_version, it can be:
 514          * 0: At least 8K, but less than 12K, from end of device
 515          * 1: At start of device
 516          * 2: 4K from start of device.
 517          */
 518         switch(st->minor_version) {
 519         case 0:
 520                 sb_offset = size;
 521                 sb_offset -= 8*2;
 522                 sb_offset &= ~(4*2-1);
 523                 sb->super_offset = __cpu_to_le64(sb_offset);
 524                 sb->data_offset = __cpu_to_le64(0);
 525                 sb->data_size = sb->super_offset;
 526                 break;
 527         case 1:
 528                 sb->super_offset = __cpu_to_le64(0);
 529                 sb->data_offset = __cpu_to_le64(2);
 530                 sb->data_size = __cpu_to_le64(size - 2);
 531                 break;
 532         case 2:
 533                 sb_offset = 4*2;
 534                 sb->super_offset = __cpu_to_le64(sb_offset);
 535                 sb->data_offset = __cpu_to_le64(sb_offset+2);
 536                 sb->data_size = __cpu_to_le64(size - 4*2 - 2);
 537                 break;
 538         default:
 539                 return -EINVAL;
 540         }
 541
 542
 543         sb->sb_csum = calc_sb_1_csum(sb);
 544         rv = store_super1(fd, sb);
 545         if (rv)
 546                 fprintf(stderr, Name ": failed to write superblock to %s\n", devname);
 547         close(fd);
 548         return rv;
 549 }
 550
 551 static int compare_super1(void **firstp, void *secondv)
 552 {
 553         /*
 554          * return:
 555          *  0 same, or first was empty, and second was copied
 556          *  1 second had wrong number
 557          *  2 wrong uuid
 558          *  3 wrong other info
 559          */
 560         struct mdp_superblock_1 *first = *firstp;
 561         struct mdp_superblock_1 *second = secondv;
 562
 563         if (second->magic != __cpu_to_le32(MD_SB_MAGIC))
 564                 return 1;
 565         if (second->major_version != __cpu_to_le32(1))
 566                 return 1;
 567
 568         if (!first) {
 569                 first = malloc(1024);
 570                 memcpy(first, second, 1024);
 571                 *firstp = first;
 572                 return 0;
 573         }
 574         if (memcmp(first->set_uuid, second->set_uuid, 16)!= 0)
 575                 return 2;
 576
 577         if (first->ctime      != second->ctime     ||
 578             first->level      != second->level     ||
 579             first->layout     != second->layout    ||
 580             first->size       != second->size      ||
 581             first->chunksize  != second->chunksize ||
 582             first->raid_disks != second->raid_disks)
 583                 return 3;
 584         return 0;
 585 }
 586
 587 static int load_super1(struct supertype *st, int fd, void **sbp, char *devname)
 588 {
 589         unsigned long size;
 590         unsigned long long sb_offset;
 591         struct mdp_superblock_1 *super;
 592
 593
 594
 595         if (st->ss == NULL) {
 596                 int bestvers = -1;
 597                 __u64 bestctime = 0;
 598                 /* guess... choose latest ctime */
 599                 st->ss = &super1;
 600                 for (st->minor_version = 0; st->minor_version <= 2 ; st->minor_version++) {
 601                         switch(load_super1(st, fd, sbp, devname)) {
 602                         case 0: super = *sbp;
 603                                 if (bestvers == -1 ||
 604                                     bestctime < __le64_to_cpu(super->ctime)) {
 605                                         bestvers = st->minor_version;
 606                                         bestctime = __le64_to_cpu(super->ctime);
 607                                 }
 608                                 free(super);
 609                                 *sbp = NULL;
 610                                 break;
 611                         case 1: st->ss = NULL; return 1; /*bad device */
 612                         case 2: break; /* bad, try next */
 613                         }
 614                 }
 615                 if (bestvers != -1) {
 616                         int rv;
 617                         st->minor_version = bestvers;
 618                         st->ss = &super1;
 619                         rv = load_super1(st, fd, sbp, devname);
 620                         if (rv) st->ss = NULL;
 621                         return rv;
 622                 }
 623                 st->ss = NULL;
 624                 return 2;
 625         }
 626         if (ioctl(fd, BLKGETSIZE, &size)) {
 627                 if (devname)
 628                         fprintf(stderr, Name ": cannot find device size for %s: %s\n",
 629                                 devname, strerror(errno));
 630                 return 1;
 631         }
 632
 633         if (size < 24) {
 634                 if (devname)
 635                         fprintf(stderr, Name ": %s is too small for md: size is %lu sectors.\n",
 636                                 devname, size);
 637                 return 1;
 638         }
 639
 640         /*
 641          * Calculate the position of the superblock.
 642          * It is always aligned to a 4K boundary and
 643          * depeding on minor_version, it can be:
 644          * 0: At least 8K, but less than 12K, from end of device
 645          * 1: At start of device
 646          * 2: 4K from start of device.
 647          */
 648         switch(st->minor_version) {
 649         case 0:
 650                 sb_offset = size;
 651                 sb_offset -= 8*2;
 652                 sb_offset &= ~(4*2-1);
 653                 break;
 654         case 1:
 655                 sb_offset = 0;
 656                 break;
 657         case 2:
 658                 sb_offset = 4*2;
 659                 break;
 660         default:
 661                 return -EINVAL;
 662         }
 663
 664         ioctl(fd, BLKFLSBUF, 0); /* make sure we read current data */
 665
 666
 667         if (lseek64(fd, sb_offset << 9, 0)< 0LL) {
 668                 if (devname)
 669                         fprintf(stderr, Name ": Cannot seek to superblock on %s: %s\n",
 670                                 devname, strerror(errno));
 671                 return 1;
 672         }
 673
 674         super = malloc(1024);
 675
 676         if (read(fd, super, 1024) != 1024) {
 677                 if (devname)
 678                         fprintf(stderr, Name ": Cannot read superblock on %s\n",
 679                                 devname);
 680                 free(super);
 681                 return 1;
 682         }
 683
 684         if (__le32_to_cpu(super->magic) != MD_SB_MAGIC) {
 685                 if (devname)
 686                         fprintf(stderr, Name ": No super block found on %s (Expected magic %08x, got %08x)\n",
 687                                 devname, MD_SB_MAGIC, __le32_to_cpu(super->magic));
 688                 free(super);
 689                 return 2;
 690         }
 691
 692         if (__le32_to_cpu(super->major_version) != 1) {
 693                 if (devname)
 694                         fprintf(stderr, Name ": Cannot interpret superblock on %s - version is %d\n",
 695                                 devname, __le32_to_cpu(super->major_version));
 696                 free(super);
 697                 return 2;
 698         }
 699         if (__le64_to_cpu(super->super_offset) != sb_offset) {
 700                 if (devname)
 701                         fprintf(stderr, Name ": No superblock found on %s (super_offset is wrong)\n",
 702                                 devname);
 703                 free(super);
 704                 return 2;
 705         }
 706         *sbp = super;
 707         return 0;
 708 }
 709
 710
 711 static struct supertype *match_metadata_desc1(char *arg)
 712 {
 713         struct supertype *st = malloc(sizeof(*st));
 714         if (!st) return st;
 715
 716         st->ss = &super1;
 717         if (strcmp(arg, "1") == 0 ||
 718             strcmp(arg, "1.0") == 0) {
 719                 st->minor_version = 0;
 720                 return st;
 721         }
 722         if (strcmp(arg, "1.1") == 0) {
 723                 st->minor_version = 1;
 724                 return st;
 725         }
 726         if (strcmp(arg, "1.2") == 0) {
 727                 st->minor_version = 2;
 728                 return st;
 729         }
 730
 731         free(st);
 732         return NULL;
 733 }
 734
 735 static __u64 avail_size1(__u64 devsize)
 736 {
 737         if (devsize < 24)
 738                 return 0;
 739
 740         return (devsize - 8*2 ) & ~(4*2-1);
 741 }
 742
 743 struct superswitch super1 = {
 744         .examine_super = examine_super1,
 745         .brief_examine_super = brief_examine_super1,
 746         .detail_super = detail_super1,
 747         .brief_detail_super = brief_detail_super1,
 748         .uuid_from_super = uuid_from_super1,
 749         .getinfo_super = getinfo_super1,
 750         .update_super = update_super1,
 751         .event_super = event_super1,
 752         .init_super = init_super1,
 753         .add_to_super = add_to_super1,
 754         .store_super = store_super1,
 755         .write_init_super = write_init_super1,
 756         .compare_super = compare_super1,
 757         .load_super = load_super1,
 758         .match_metadata_desc = match_metadata_desc1,
 759         .avail_size = avail_size1,
 760         .major = 1,
 761 };