util.c

   1 /*
   2  * mdadm - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001-2009 Neil Brown <neilb@suse.de>
   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@suse.de>
  23  */
  24
  25 #include        "mdadm.h"
  26 #include        "md_p.h"
  27 #include        <sys/socket.h>
  28 #include        <sys/utsname.h>
  29 #include        <sys/wait.h>
  30 #include        <sys/un.h>
  31 #include        <ctype.h>
  32 #include        <dirent.h>
  33 #include        <signal.h>
  34
  35 /*
  36  * following taken from linux/blkpg.h because they aren't
  37  * anywhere else and it isn't safe to #include linux/ * stuff.
  38  */
  39
  40 #define BLKPG      _IO(0x12,105)
  41
  42 /* The argument structure */
  43 struct blkpg_ioctl_arg {
  44         int op;
  45         int flags;
  46         int datalen;
  47         void *data;
  48 };
  49
  50 /* The subfunctions (for the op field) */
  51 #define BLKPG_ADD_PARTITION     1
  52 #define BLKPG_DEL_PARTITION     2
  53
  54 /* Sizes of name fields. Unused at present. */
  55 #define BLKPG_DEVNAMELTH        64
  56 #define BLKPG_VOLNAMELTH        64
  57
  58 /* The data structure for ADD_PARTITION and DEL_PARTITION */
  59 struct blkpg_partition {
  60         long long start;                /* starting offset in bytes */
  61         long long length;               /* length in bytes */
  62         int pno;                        /* partition number */
  63         char devname[BLKPG_DEVNAMELTH]; /* partition name, like sda5 or c0d1p2,
  64                                            to be used in kernel messages */
  65         char volname[BLKPG_VOLNAMELTH]; /* volume label */
  66 };
  67
  68 /* partition table structures so we can check metadata position
  69  * against the end of the last partition.
  70  * Only handle MBR ant GPT partition tables.
  71  */
  72 struct MBR_part_record {
  73   __u8 bootable;
  74   __u8 first_head;
  75   __u8 first_sector;
  76   __u8 first_cyl;
  77   __u8 part_type;
  78   __u8 last_head;
  79   __u8 last_sector;
  80   __u8 last_cyl;
  81   __u32 first_sect_lba;
  82   __u32 blocks_num;
  83 };
  84
  85 struct MBR {
  86         __u8 pad[446];
  87         struct MBR_part_record parts[4];
  88         __u16 magic;
  89 } __attribute__((packed));
  90
  91 struct GPT_part_entry {
  92   unsigned char type_guid[16];
  93   unsigned char partition_guid[16];
  94   __u64 starting_lba;
  95   __u64 ending_lba;
  96   unsigned char attr_bits[8];
  97   unsigned char name[72];
  98 } __attribute__((packed));
  99
 100 struct GPT {
 101         __u64 magic;
 102         __u32 revision;
 103         __u32 header_size;
 104         __u32 crc;
 105         __u32 pad1;
 106         __u64 current_lba;
 107         __u64 backup_lba;
 108         __u64 first_lba;
 109         __u64 last_lba;
 110         __u8 guid[16];
 111         __u64 part_start;
 112         __u32 part_cnt;
 113         __u32 part_size;
 114         __u32 part_crc;
 115         __u8 pad2[420];
 116 } __attribute__((packed));
 117
 118 /* Force a compilation error if condition is true */
 119 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
 120
 121 /* Force a compilation error if condition is true, but also produce a
 122    result (of value 0 and type size_t), so the expression can be used
 123    e.g. in a structure initializer (or where-ever else comma expressions
 124    aren't permitted). */
 125 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
 126
 127
 128 /* MBR/GPT magic numbers */
 129 #define MBR_SIGNATURE_MAGIC     __cpu_to_le16(0xAA55)
 130 #define GPT_SIGNATURE_MAGIC     __cpu_to_le64(0x5452415020494645ULL)
 131
 132 #define MBR_PARTITIONS               4
 133 #define MBR_GPT_PARTITION_TYPE       0xEE
 134
 135 /*
 136  * Parse a 128 bit uuid in 4 integers
 137  * format is 32 hexx nibbles with options :.<space> separator
 138  * If not exactly 32 hex digits are found, return 0
 139  * else return 1
 140  */
 141 int parse_uuid(char *str, int uuid[4])
 142 {
 143         int hit = 0; /* number of Hex digIT */
 144         int i;
 145         char c;
 146         for (i=0; i<4; i++) uuid[i]=0;
 147
 148         while ((c= *str++)) {
 149                 int n;
 150                 if (c>='0' && c<='9')
 151                         n = c-'0';
 152                 else if (c>='a' && c <= 'f')
 153                         n = 10 + c - 'a';
 154                 else if (c>='A' && c <= 'F')
 155                         n = 10 + c - 'A';
 156                 else if (strchr(":. -", c))
 157                         continue;
 158                 else return 0;
 159
 160                 if (hit<32) {
 161                         uuid[hit/8] <<= 4;
 162                         uuid[hit/8] += n;
 163                 }
 164                 hit++;
 165         }
 166         if (hit == 32)
 167                 return 1;
 168         return 0;
 169 }
 170
 171
 172 /*
 173  * Get the md version number.
 174  * We use the RAID_VERSION ioctl if it is supported
 175  * If not, but we have a block device with major '9', we assume
 176  * 0.36.0
 177  *
 178  * Return version number as 24 but number - assume version parts
 179  * always < 255
 180  */
 181
 182 int md_get_version(int fd)
 183 {
 184     struct stat stb;
 185     mdu_version_t vers;
 186
 187     if (fstat(fd, &stb)<0)
 188         return -1;
 189     if ((S_IFMT&stb.st_mode) != S_IFBLK)
 190         return -1;
 191
 192     if (ioctl(fd, RAID_VERSION, &vers) == 0)
 193         return  (vers.major*10000) + (vers.minor*100) + vers.patchlevel;
 194     if (errno == EACCES)
 195             return -1;
 196     if (major(stb.st_rdev) == MD_MAJOR)
 197         return (3600);
 198     return -1;
 199 }
 200
 201 int get_linux_version()
 202 {
 203         struct utsname name;
 204         char *cp;
 205         int a,b,c;
 206         if (uname(&name) <0)
 207                 return -1;
 208
 209         cp = name.release;
 210         a = strtoul(cp, &cp, 10);
 211         if (*cp != '.') return -1;
 212         b = strtoul(cp+1, &cp, 10);
 213         if (*cp != '.') return -1;
 214         c = strtoul(cp+1, NULL, 10);
 215
 216         return (a*1000000)+(b*1000)+c;
 217 }
 218
 219 #ifndef MDASSEMBLE
 220 long long parse_size(char *size)
 221 {
 222         /* parse 'size' which should be a number optionally
 223          * followed by 'K', 'M', or 'G'.
 224          * Without a suffix, K is assumed.
 225          * Number returned is in sectors (half-K)
 226          */
 227         char *c;
 228         long long s = strtoll(size, &c, 10);
 229         if (s > 0) {
 230                 switch (*c) {
 231                 case 'K':
 232                         c++;
 233                 default:
 234                         s *= 2;
 235                         break;
 236                 case 'M':
 237                         c++;
 238                         s *= 1024 * 2;
 239                         break;
 240                 case 'G':
 241                         c++;
 242                         s *= 1024 * 1024 * 2;
 243                         break;
 244                 }
 245         }
 246         if (*c)
 247                 s = 0;
 248         return s;
 249 }
 250
 251 int parse_layout_10(char *layout)
 252 {
 253         int copies, rv;
 254         char *cp;
 255         /* Parse the layout string for raid10 */
 256         /* 'f', 'o' or 'n' followed by a number <= raid_disks */
 257         if ((layout[0] !=  'n' && layout[0] != 'f' && layout[0] != 'o') ||
 258             (copies = strtoul(layout+1, &cp, 10)) < 1 ||
 259             copies > 200 ||
 260             *cp)
 261                 return -1;
 262         if (layout[0] == 'n')
 263                 rv = 256 + copies;
 264         else if (layout[0] == 'o')
 265                 rv = 0x10000 + (copies<<8) + 1;
 266         else
 267                 rv = 1 + (copies<<8);
 268         return rv;
 269 }
 270
 271 int parse_layout_faulty(char *layout)
 272 {
 273         /* Parse the layout string for 'faulty' */
 274         int ln = strcspn(layout, "0123456789");
 275         char *m = strdup(layout);
 276         int mode;
 277         m[ln] = 0;
 278         mode = map_name(faultylayout, m);
 279         if (mode == UnSet)
 280                 return -1;
 281
 282         return mode | (atoi(layout+ln)<< ModeShift);
 283 }
 284 #endif
 285
 286 void remove_partitions(int fd)
 287 {
 288         /* remove partitions from this block devices.
 289          * This is used for components added to an array
 290          */
 291 #ifdef BLKPG_DEL_PARTITION
 292         struct blkpg_ioctl_arg a;
 293         struct blkpg_partition p;
 294
 295         a.op = BLKPG_DEL_PARTITION;
 296         a.data = (void*)&p;
 297         a.datalen = sizeof(p);
 298         a.flags = 0;
 299         memset(a.data, 0, a.datalen);
 300         for (p.pno=0; p.pno < 16; p.pno++)
 301                 ioctl(fd, BLKPG, &a);
 302 #endif
 303 }
 304
 305 int enough(int level, int raid_disks, int layout, int clean,
 306            char *avail, int avail_disks)
 307 {
 308         int copies, first;
 309         switch (level) {
 310         case 10:
 311                 /* This is the tricky one - we need to check
 312                  * which actual disks are present.
 313                  */
 314                 copies = (layout&255)* ((layout>>8) & 255);
 315                 first=0;
 316                 do {
 317                         /* there must be one of the 'copies' form 'first' */
 318                         int n = copies;
 319                         int cnt=0;
 320                         while (n--) {
 321                                 if (avail[first])
 322                                         cnt++;
 323                                 first = (first+1) % raid_disks;
 324                         }
 325                         if (cnt == 0)
 326                                 return 0;
 327
 328                 } while (first != 0);
 329                 return 1;
 330
 331         case LEVEL_MULTIPATH:
 332                 return avail_disks>= 1;
 333         case LEVEL_LINEAR:
 334         case 0:
 335                 return avail_disks == raid_disks;
 336         case 1:
 337                 return avail_disks >= 1;
 338         case 4:
 339         case 5:
 340                 if (clean)
 341                         return avail_disks >= raid_disks-1;
 342                 else
 343                         return avail_disks >= raid_disks;
 344         case 6:
 345                 if (clean)
 346                         return avail_disks >= raid_disks-2;
 347                 else
 348                         return avail_disks >= raid_disks;
 349         default:
 350                 return 0;
 351         }
 352 }
 353
 354 const int uuid_match_any[4] = { ~0, ~0, ~0, ~0 };
 355 int same_uuid(int a[4], int b[4], int swapuuid)
 356 {
 357         if (memcmp(a, uuid_match_any, sizeof(int[4])) == 0 ||
 358             memcmp(b, uuid_match_any, sizeof(int[4])) == 0)
 359                 return 1;
 360
 361         if (swapuuid) {
 362                 /* parse uuids are hostendian.
 363                  * uuid's from some superblocks are big-ending
 364                  * if there is a difference, we need to swap..
 365                  */
 366                 unsigned char *ac = (unsigned char *)a;
 367                 unsigned char *bc = (unsigned char *)b;
 368                 int i;
 369                 for (i=0; i<16; i+= 4) {
 370                         if (ac[i+0] != bc[i+3] ||
 371                             ac[i+1] != bc[i+2] ||
 372                             ac[i+2] != bc[i+1] ||
 373                             ac[i+3] != bc[i+0])
 374                                 return 0;
 375                 }
 376                 return 1;
 377         } else {
 378                 if (a[0]==b[0] &&
 379                     a[1]==b[1] &&
 380                     a[2]==b[2] &&
 381                     a[3]==b[3])
 382                         return 1;
 383                 return 0;
 384         }
 385 }
 386 void copy_uuid(void *a, int b[4], int swapuuid)
 387 {
 388         if (swapuuid) {
 389                 /* parse uuids are hostendian.
 390                  * uuid's from some superblocks are big-ending
 391                  * if there is a difference, we need to swap..
 392                  */
 393                 unsigned char *ac = (unsigned char *)a;
 394                 unsigned char *bc = (unsigned char *)b;
 395                 int i;
 396                 for (i=0; i<16; i+= 4) {
 397                         ac[i+0] = bc[i+3];
 398                         ac[i+1] = bc[i+2];
 399                         ac[i+2] = bc[i+1];
 400                         ac[i+3] = bc[i+0];
 401                 }
 402         } else
 403                 memcpy(a, b, 16);
 404 }
 405
 406 char *__fname_from_uuid(int id[4], int swap, char *buf, char sep)
 407 {
 408         int i, j;
 409         char uuid[16];
 410         char *c = buf;
 411         strcpy(c, "UUID-");
 412         c += strlen(c);
 413         copy_uuid(uuid, id, swap);
 414         for (i = 0; i < 4; i++) {
 415                 if (i)
 416                         *c++ = sep;
 417                 for (j = 3; j >= 0; j--) {
 418                         sprintf(c,"%02x", (unsigned char) uuid[j+4*i]);
 419                         c+= 2;
 420                 }
 421         }
 422         return buf;
 423
 424 }
 425
 426 char *fname_from_uuid(struct supertype *st, struct mdinfo *info, char *buf, char sep)
 427 {
 428         // dirty hack to work around an issue with super1 superblocks...
 429         // super1 superblocks need swapuuid set in order for assembly to
 430         // work, but can't have it set if we want this printout to match
 431         // all the other uuid printouts in super1.c, so we force swapuuid
 432         // to 1 to make our printout match the rest of super1
 433         return __fname_from_uuid(info->uuid, (st->ss == &super1) ? 1 : st->ss->swapuuid, buf, sep);
 434 }
 435
 436 #ifndef MDASSEMBLE
 437 int check_ext2(int fd, char *name)
 438 {
 439         /*
 440          * Check for an ext2fs file system.
 441          * Superblock is always 1K at 1K offset
 442          *
 443          * s_magic is le16 at 56 == 0xEF53
 444          * report mtime - le32 at 44
 445          * blocks - le32 at 4
 446          * logblksize - le32 at 24
 447          */
 448         unsigned char sb[1024];
 449         time_t mtime;
 450         int size, bsize;
 451         if (lseek(fd, 1024,0)!= 1024)
 452                 return 0;
 453         if (read(fd, sb, 1024)!= 1024)
 454                 return 0;
 455         if (sb[56] != 0x53 || sb[57] != 0xef)
 456                 return 0;
 457
 458         mtime = sb[44]|(sb[45]|(sb[46]|sb[47]<<8)<<8)<<8;
 459         bsize = sb[24]|(sb[25]|(sb[26]|sb[27]<<8)<<8)<<8;
 460         size = sb[4]|(sb[5]|(sb[6]|sb[7]<<8)<<8)<<8;
 461         fprintf(stderr, Name ": %s appears to contain an ext2fs file system\n",
 462                 name);
 463         fprintf(stderr,"    size=%dK  mtime=%s",
 464                 size*(1<<bsize), ctime(&mtime));
 465         return 1;
 466 }
 467
 468 int check_reiser(int fd, char *name)
 469 {
 470         /*
 471          * superblock is at 64K
 472          * size is 1024;
 473          * Magic string "ReIsErFs" or "ReIsEr2Fs" at 52
 474          *
 475          */
 476         unsigned char sb[1024];
 477         unsigned long size;
 478         if (lseek(fd, 64*1024, 0) != 64*1024)
 479                 return 0;
 480         if (read(fd, sb, 1024) != 1024)
 481                 return 0;
 482         if (strncmp((char*)sb+52, "ReIsErFs",8)!=0 &&
 483             strncmp((char*)sb+52, "ReIsEr2Fs",9)!=0)
 484                 return 0;
 485         fprintf(stderr, Name ": %s appears to contain a reiserfs file system\n",name);
 486         size = sb[0]|(sb[1]|(sb[2]|sb[3]<<8)<<8)<<8;
 487         fprintf(stderr, "    size = %luK\n", size*4);
 488
 489         return 1;
 490 }
 491
 492 int check_raid(int fd, char *name)
 493 {
 494         struct mdinfo info;
 495         time_t crtime;
 496         char *level;
 497         struct supertype *st = guess_super(fd);
 498
 499         if (!st) return 0;
 500         st->ss->load_super(st, fd, name);
 501         /* Looks like a raid array .. */
 502         fprintf(stderr, Name ": %s appears to be part of a raid array:\n",
 503                 name);
 504         st->ss->getinfo_super(st, &info);
 505         st->ss->free_super(st);
 506         crtime = info.array.ctime;
 507         level = map_num(pers, info.array.level);
 508         if (!level) level = "-unknown-";
 509         fprintf(stderr, "    level=%s devices=%d ctime=%s",
 510                 level, info.array.raid_disks, ctime(&crtime));
 511         return 1;
 512 }
 513
 514 int ask(char *mesg)
 515 {
 516         char *add = "";
 517         int i;
 518         for (i=0; i<5; i++) {
 519                 char buf[100];
 520                 fprintf(stderr, "%s%s", mesg, add);
 521                 fflush(stderr);
 522                 if (fgets(buf, 100, stdin)==NULL)
 523                         return 0;
 524                 if (buf[0]=='y' || buf[0]=='Y')
 525                         return 1;
 526                 if (buf[0]=='n' || buf[0]=='N')
 527                         return 0;
 528                 add = "(y/n) ";
 529         }
 530         fprintf(stderr, Name ": assuming 'no'\n");
 531         return 0;
 532 }
 533 #endif /* MDASSEMBLE */
 534
 535 char *map_num(mapping_t *map, int num)
 536 {
 537         while (map->name) {
 538                 if (map->num == num)
 539                         return map->name;
 540                 map++;
 541         }
 542         return NULL;
 543 }
 544
 545 int map_name(mapping_t *map, char *name)
 546 {
 547         while (map->name) {
 548                 if (strcmp(map->name, name)==0)
 549                         return map->num;
 550                 map++;
 551         }
 552         return UnSet;
 553 }
 554
 555
 556 int is_standard(char *dev, int *nump)
 557 {
 558         /* tests if dev is a "standard" md dev name.
 559          * i.e if the last component is "/dNN" or "/mdNN",
 560          * where NN is a string of digits
 561          * Returns 1 if a partitionable standard,
 562          *   -1 if non-partitonable,
 563          *   0 if not a standard name.
 564          */
 565         char *d = strrchr(dev, '/');
 566         int type=0;
 567         int num;
 568         if (!d)
 569                 return 0;
 570         if (strncmp(d, "/d",2)==0)
 571                 d += 2, type=1; /* /dev/md/dN{pM} */
 572         else if (strncmp(d, "/md_d", 5)==0)
 573                 d += 5, type=1; /* /dev/md_dN{pM} */
 574         else if (strncmp(d, "/md", 3)==0)
 575                 d += 3, type=-1; /* /dev/mdN */
 576         else if (d-dev > 3 && strncmp(d-2, "md/", 3)==0)
 577                 d += 1, type=-1; /* /dev/md/N */
 578         else
 579                 return 0;
 580         if (!*d)
 581                 return 0;
 582         num = atoi(d);
 583         while (isdigit(*d))
 584                 d++;
 585         if (*d)
 586                 return 0;
 587         if (nump) *nump = num;
 588
 589         return type;
 590 }
 591
 592
 593 /*
 594  * convert a major/minor pair for a block device into a name in /dev, if possible.
 595  * On the first call, walk /dev collecting name.
 596  * Put them in a simple linked listfor now.
 597  */
 598 struct devmap {
 599     int major, minor;
 600     char *name;
 601     struct devmap *next;
 602 } *devlist = NULL;
 603 int devlist_ready = 0;
 604
 605 int add_dev(const char *name, const struct stat *stb, int flag, struct FTW *s)
 606 {
 607         struct stat st;
 608
 609         if (S_ISLNK(stb->st_mode)) {
 610                 if (stat(name, &st) != 0)
 611                         return 0;
 612                 stb = &st;
 613         }
 614
 615         if ((stb->st_mode&S_IFMT)== S_IFBLK) {
 616                 char *n = strdup(name);
 617                 struct devmap *dm = malloc(sizeof(*dm));
 618                 if (strncmp(n, "/dev/./", 7)==0)
 619                         strcpy(n+4, name+6);
 620                 if (dm) {
 621                         dm->major = major(stb->st_rdev);
 622                         dm->minor = minor(stb->st_rdev);
 623                         dm->name = n;
 624                         dm->next = devlist;
 625                         devlist = dm;
 626                 }
 627         }
 628         return 0;
 629 }
 630
 631 #ifndef HAVE_NFTW
 632 #ifdef HAVE_FTW
 633 int add_dev_1(const char *name, const struct stat *stb, int flag)
 634 {
 635         return add_dev(name, stb, flag, NULL);
 636 }
 637 int nftw(const char *path, int (*han)(const char *name, const struct stat *stb, int flag, struct FTW *s), int nopenfd, int flags)
 638 {
 639         return ftw(path, add_dev_1, nopenfd);
 640 }
 641 #else
 642 int nftw(const char *path, int (*han)(const char *name, const struct stat *stb, int flag, struct FTW *s), int nopenfd, int flags)
 643 {
 644         return 0;
 645 }
 646 #endif /* HAVE_FTW */
 647 #endif /* HAVE_NFTW */
 648
 649 /*
 650  * Find a block device with the right major/minor number.
 651  * If we find multiple names, choose the shortest.
 652  * If we find a name in /dev/md/, we prefer that.
 653  * This applies only to names for MD devices.
 654  */
 655 char *map_dev(int major, int minor, int create)
 656 {
 657         struct devmap *p;
 658         char *regular = NULL, *preferred=NULL;
 659         int did_check = 0;
 660
 661         if (major == 0 && minor == 0)
 662                         return NULL;
 663
 664  retry:
 665         if (!devlist_ready) {
 666                 char *dev = "/dev";
 667                 struct stat stb;
 668                 while(devlist) {
 669                         struct devmap *d = devlist;
 670                         devlist = d->next;
 671                         free(d->name);
 672                         free(d);
 673                 }
 674                 if (lstat(dev, &stb)==0 &&
 675                     S_ISLNK(stb.st_mode))
 676                         dev = "/dev/.";
 677                 nftw(dev, add_dev, 10, FTW_PHYS);
 678                 devlist_ready=1;
 679                 did_check = 1;
 680         }
 681
 682         for (p=devlist; p; p=p->next)
 683                 if (p->major == major &&
 684                     p->minor == minor) {
 685                         if (strncmp(p->name, "/dev/md/",8) == 0) {
 686                                 if (preferred == NULL ||
 687                                     strlen(p->name) < strlen(preferred))
 688                                         preferred = p->name;
 689                         } else {
 690                                 if (regular == NULL ||
 691                                     strlen(p->name) < strlen(regular))
 692                                         regular = p->name;
 693                         }
 694                 }
 695         if (!regular && !preferred && !did_check) {
 696                 devlist_ready = 0;
 697                 goto retry;
 698         }
 699         if (create && !regular && !preferred) {
 700                 static char buf[30];
 701                 snprintf(buf, sizeof(buf), "%d:%d", major, minor);
 702                 regular = buf;
 703         }
 704
 705         return preferred ? preferred : regular;
 706 }
 707
 708 unsigned long calc_csum(void *super, int bytes)
 709 {
 710         unsigned long long newcsum = 0;
 711         int i;
 712         unsigned int csum;
 713         unsigned int *superc = (unsigned int*) super;
 714
 715         for(i=0; i<bytes/4; i++)
 716                 newcsum+= superc[i];
 717         csum = (newcsum& 0xffffffff) + (newcsum>>32);
 718 #ifdef __alpha__
 719 /* The in-kernel checksum calculation is always 16bit on
 720  * the alpha, though it is 32 bit on i386...
 721  * I wonder what it is elsewhere... (it uses and API in
 722  * a way that it shouldn't).
 723  */
 724         csum = (csum & 0xffff) + (csum >> 16);
 725         csum = (csum & 0xffff) + (csum >> 16);
 726 #endif
 727         return csum;
 728 }
 729
 730 #ifndef MDASSEMBLE
 731 char *human_size(long long bytes)
 732 {
 733         static char buf[30];
 734
 735         /* We convert bytes to either centi-M{ega,ibi}bytes or
 736          * centi-G{igi,ibi}bytes, with appropriate rounding,
 737          * and then print 1/100th of those as a decimal.
 738          * We allow upto 2048Megabytes before converting to
 739          * gigabytes, as that shows more precision and isn't
 740          * too large a number.
 741          * Terrabytes are not yet handled.
 742          */
 743
 744         if (bytes < 5000*1024)
 745                 buf[0]=0;
 746         else if (bytes < 2*1024LL*1024LL*1024LL) {
 747                 long cMiB = (bytes / ( (1LL<<20) / 200LL ) +1) /2;
 748                 long cMB  = (bytes / ( 1000000LL / 200LL ) +1) /2;
 749                 snprintf(buf, sizeof(buf), " (%ld.%02ld MiB %ld.%02ld MB)",
 750                         cMiB/100 , cMiB % 100,
 751                         cMB/100, cMB % 100);
 752         } else {
 753                 long cGiB = (bytes / ( (1LL<<30) / 200LL ) +1) /2;
 754                 long cGB  = (bytes / (1000000000LL/200LL ) +1) /2;
 755                 snprintf(buf, sizeof(buf), " (%ld.%02ld GiB %ld.%02ld GB)",
 756                         cGiB/100 , cGiB % 100,
 757                         cGB/100, cGB % 100);
 758         }
 759         return buf;
 760 }
 761
 762 char *human_size_brief(long long bytes)
 763 {
 764         static char buf[30];
 765
 766         if (bytes < 5000*1024)
 767                 snprintf(buf, sizeof(buf), "%ld.%02ldKiB",
 768                         (long)(bytes>>10), (long)(((bytes&1023)*100+512)/1024)
 769                         );
 770         else if (bytes < 2*1024LL*1024LL*1024LL)
 771                 snprintf(buf, sizeof(buf), "%ld.%02ldMiB",
 772                         (long)(bytes>>20),
 773                         (long)((bytes&0xfffff)+0x100000/200)/(0x100000/100)
 774                         );
 775         else
 776                 snprintf(buf, sizeof(buf), "%ld.%02ldGiB",
 777                         (long)(bytes>>30),
 778                         (long)(((bytes>>10)&0xfffff)+0x100000/200)/(0x100000/100)
 779                         );
 780         return buf;
 781 }
 782
 783 void print_r10_layout(int layout)
 784 {
 785         int near = layout & 255;
 786         int far = (layout >> 8) & 255;
 787         int offset = (layout&0x10000);
 788         char *sep = "";
 789
 790         if (near != 1) {
 791                 printf("%s near=%d", sep, near);
 792                 sep = ",";
 793         }
 794         if (far != 1)
 795                 printf("%s %s=%d", sep, offset?"offset":"far", far);
 796         if (near*far == 1)
 797                 printf("NO REDUNDANCY");
 798 }
 799 #endif
 800
 801 unsigned long long calc_array_size(int level, int raid_disks, int layout,
 802                                    int chunksize, unsigned long long devsize)
 803 {
 804         int data_disks = 0;
 805         switch (level) {
 806         case 0: data_disks = raid_disks; break;
 807         case 1: data_disks = 1; break;
 808         case 4:
 809         case 5: data_disks = raid_disks - 1; break;
 810         case 6: data_disks = raid_disks - 2; break;
 811         case 10: data_disks = raid_disks / (layout & 255) / ((layout>>8)&255);
 812                 break;
 813         }
 814         devsize &= ~(unsigned long long)((chunksize>>9)-1);
 815         return data_disks * devsize;
 816 }
 817
 818 int get_mdp_major(void)
 819 {
 820 static int mdp_major = -1;
 821         FILE *fl;
 822         char *w;
 823         int have_block = 0;
 824         int have_devices = 0;
 825         int last_num = -1;
 826
 827         if (mdp_major != -1)
 828                 return mdp_major;
 829         fl = fopen("/proc/devices", "r");
 830         if (!fl)
 831                 return -1;
 832         while ((w = conf_word(fl, 1))) {
 833                 if (have_block && strcmp(w, "devices:")==0)
 834                         have_devices = 1;
 835                 have_block =  (strcmp(w, "Block")==0);
 836                 if (isdigit(w[0]))
 837                         last_num = atoi(w);
 838                 if (have_devices && strcmp(w, "mdp")==0)
 839                         mdp_major = last_num;
 840                 free(w);
 841         }
 842         fclose(fl);
 843         return mdp_major;
 844 }
 845
 846 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
 847 char *get_md_name(int dev)
 848 {
 849         /* find /dev/md%d or /dev/md/%d or make a device /dev/.tmp.md%d */
 850         /* if dev < 0, want /dev/md/d%d or find mdp in /proc/devices ... */
 851         static char devname[50];
 852         struct stat stb;
 853         dev_t rdev;
 854         char *dn;
 855
 856         if (dev < 0) {
 857                 int mdp =  get_mdp_major();
 858                 if (mdp < 0) return NULL;
 859                 rdev = makedev(mdp, (-1-dev)<<6);
 860                 snprintf(devname, sizeof(devname), "/dev/md/d%d", -1-dev);
 861                 if (stat(devname, &stb) == 0
 862                     && (S_IFMT&stb.st_mode) == S_IFBLK
 863                     && (stb.st_rdev == rdev))
 864                         return devname;
 865         } else {
 866                 rdev = makedev(MD_MAJOR, dev);
 867                 snprintf(devname, sizeof(devname), "/dev/md%d", dev);
 868                 if (stat(devname, &stb) == 0
 869                     && (S_IFMT&stb.st_mode) == S_IFBLK
 870                     && (stb.st_rdev == rdev))
 871                         return devname;
 872
 873                 snprintf(devname, sizeof(devname), "/dev/md/%d", dev);
 874                 if (stat(devname, &stb) == 0
 875                     && (S_IFMT&stb.st_mode) == S_IFBLK
 876                     && (stb.st_rdev == rdev))
 877                         return devname;
 878         }
 879         dn = map_dev(major(rdev), minor(rdev), 0);
 880         if (dn)
 881                 return dn;
 882         snprintf(devname, sizeof(devname), "/dev/.tmp.md%d", dev);
 883         if (mknod(devname, S_IFBLK | 0600, rdev) == -1)
 884                 if (errno != EEXIST)
 885                         return NULL;
 886
 887         if (stat(devname, &stb) == 0
 888             && (S_IFMT&stb.st_mode) == S_IFBLK
 889             && (stb.st_rdev == rdev))
 890                 return devname;
 891         unlink(devname);
 892         return NULL;
 893 }
 894
 895 void put_md_name(char *name)
 896 {
 897         if (strncmp(name, "/dev/.tmp.md", 12)==0)
 898                 unlink(name);
 899 }
 900
 901 int find_free_devnum(int use_partitions)
 902 {
 903         int devnum;
 904         for (devnum = 127; devnum != 128;
 905              devnum = devnum ? devnum-1 : (1<<20)-1) {
 906                 char *dn;
 907                 int _devnum;
 908
 909                 _devnum = use_partitions ? (-1-devnum) : devnum;
 910                 if (mddev_busy(_devnum))
 911                         continue;
 912                 /* make sure it is new to /dev too, at least as a
 913                  * non-standard */
 914                 dn = map_dev(dev2major(_devnum), dev2minor(_devnum), 0);
 915                 if (dn && ! is_standard(dn, NULL))
 916                         continue;
 917                 break;
 918         }
 919         if (devnum == 128)
 920                 return NoMdDev;
 921         return use_partitions ? (-1-devnum) : devnum;
 922 }
 923 #endif /* !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO) */
 924
 925 int dev_open(char *dev, int flags)
 926 {
 927         /* like 'open', but if 'dev' matches %d:%d, create a temp
 928          * block device and open that
 929          */
 930         char *e;
 931         int fd = -1;
 932         char devname[32];
 933         int major;
 934         int minor;
 935
 936         if (!dev) return -1;
 937
 938         major = strtoul(dev, &e, 0);
 939         if (e > dev && *e == ':' && e[1] &&
 940             (minor = strtoul(e+1, &e, 0)) >= 0 &&
 941             *e == 0) {
 942                 snprintf(devname, sizeof(devname), "/dev/.tmp.md.%d:%d:%d",
 943                          (int)getpid(), major, minor);
 944                 if (mknod(devname, S_IFBLK|0600, makedev(major, minor))==0) {
 945                         fd = open(devname, flags|O_DIRECT);
 946                         unlink(devname);
 947                 }
 948         } else
 949                 fd = open(dev, flags|O_DIRECT);
 950         return fd;
 951 }
 952
 953 int open_dev(int devnum)
 954 {
 955         char buf[20];
 956
 957         sprintf(buf, "%d:%d", dev2major(devnum), dev2minor(devnum));
 958         return dev_open(buf, O_RDWR);
 959 }
 960
 961 int open_dev_excl(int devnum)
 962 {
 963         char buf[20];
 964         int i;
 965
 966         sprintf(buf, "%d:%d", dev2major(devnum), dev2minor(devnum));
 967         for (i=0 ; i<25 ; i++) {
 968                 int fd = dev_open(buf, O_RDWR|O_EXCL);
 969                 if (fd >= 0)
 970                         return fd;
 971                 if (errno != EBUSY)
 972                         return fd;
 973                 usleep(200000);
 974         }
 975         return -1;
 976 }
 977
 978 int same_dev(char *one, char *two)
 979 {
 980         struct stat st1, st2;
 981         if (stat(one, &st1) != 0)
 982                 return 0;
 983         if (stat(two, &st2) != 0)
 984                 return 0;
 985         if ((st1.st_mode & S_IFMT) != S_IFBLK)
 986                 return 0;
 987         if ((st2.st_mode & S_IFMT) != S_IFBLK)
 988                 return 0;
 989         return st1.st_rdev == st2.st_rdev;
 990 }
 991
 992 void wait_for(char *dev, int fd)
 993 {
 994         int i;
 995         struct stat stb_want;
 996
 997         if (fstat(fd, &stb_want) != 0 ||
 998             (stb_want.st_mode & S_IFMT) != S_IFBLK)
 999                 return;
1000
1001         for (i=0 ; i<25 ; i++) {
1002                 struct stat stb;
1003                 if (stat(dev, &stb) == 0 &&
1004                     (stb.st_mode & S_IFMT) == S_IFBLK &&
1005                     (stb.st_rdev == stb_want.st_rdev))
1006                         return;
1007                 usleep(200000);
1008         }
1009         if (i == 25)
1010                 dprintf("%s: timeout waiting for %s\n", __func__, dev);
1011 }
1012
1013 struct superswitch *superlist[] = { &super0, &super1, &super_ddf, &super_imsm, NULL };
1014
1015 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
1016
1017 struct supertype *super_by_fd(int fd)
1018 {
1019         mdu_array_info_t array;
1020         int vers;
1021         int minor;
1022         struct supertype *st = NULL;
1023         struct mdinfo *sra;
1024         char *verstr;
1025         char version[20];
1026         int i;
1027         char *subarray = NULL;
1028
1029         sra = sysfs_read(fd, 0, GET_VERSION);
1030
1031         if (sra) {
1032                 vers = sra->array.major_version;
1033                 minor = sra->array.minor_version;
1034                 verstr = sra->text_version;
1035         } else {
1036                 if (ioctl(fd, GET_ARRAY_INFO, &array))
1037                         array.major_version = array.minor_version = 0;
1038                 vers = array.major_version;
1039                 minor = array.minor_version;
1040                 verstr = "";
1041         }
1042
1043         if (vers != -1) {
1044                 sprintf(version, "%d.%d", vers, minor);
1045                 verstr = version;
1046         }
1047         if (minor == -2 && is_subarray(verstr)) {
1048                 char *dev = verstr+1;
1049                 subarray = strchr(dev, '/');
1050                 int devnum;
1051                 if (subarray)
1052                         *subarray++ = '\0';
1053                 devnum = devname2devnum(dev);
1054                 subarray = strdup(subarray);
1055                 if (sra)
1056                         sysfs_free(sra);
1057                 sra = sysfs_read(-1, devnum, GET_VERSION);
1058                 if (sra && sra->text_version[0])
1059                         verstr = sra->text_version;
1060                 else
1061                         verstr = "-no-metadata-";
1062         }
1063
1064         for (i = 0; st == NULL && superlist[i] ; i++)
1065                 st = superlist[i]->match_metadata_desc(verstr);
1066
1067         if (sra)
1068                 sysfs_free(sra);
1069         if (st) {
1070                 st->sb = NULL;
1071                 if (subarray) {
1072                         strncpy(st->subarray, subarray, 32);
1073                         st->subarray[31] = 0;
1074                         free(subarray);
1075                 } else
1076                         st->subarray[0] = 0;
1077         }
1078         return st;
1079 }
1080 #endif /* !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO) */
1081
1082
1083 struct supertype *dup_super(struct supertype *orig)
1084 {
1085         struct supertype *st;
1086
1087         if (!orig)
1088                 return orig;
1089         st = malloc(sizeof(*st));
1090         if (!st)
1091                 return st;
1092         memset(st, 0, sizeof(*st));
1093         st->ss = orig->ss;
1094         st->max_devs = orig->max_devs;
1095         st->minor_version = orig->minor_version;
1096         strcpy(st->subarray, orig->subarray);
1097         st->sb = NULL;
1098         st->info = NULL;
1099         return st;
1100 }
1101
1102 struct supertype *guess_super(int fd)
1103 {
1104         /* try each load_super to find the best match,
1105          * and return the best superswitch
1106          */
1107         struct superswitch  *ss;
1108         struct supertype *st;
1109         unsigned long besttime = 0;
1110         int bestsuper = -1;
1111         int i;
1112
1113         st = malloc(sizeof(*st));
1114         for (i=0 ; superlist[i]; i++) {
1115                 int rv;
1116                 ss = superlist[i];
1117                 memset(st, 0, sizeof(*st));
1118                 rv = ss->load_super(st, fd, NULL);
1119                 if (rv == 0) {
1120                         struct mdinfo info;
1121                         st->ss->getinfo_super(st, &info);
1122                         if (bestsuper == -1 ||
1123                             besttime < info.array.ctime) {
1124                                 bestsuper = i;
1125                                 besttime = info.array.ctime;
1126                         }
1127                         ss->free_super(st);
1128                 }
1129         }
1130         if (bestsuper != -1) {
1131                 int rv;
1132                 memset(st, 0, sizeof(*st));
1133                 rv = superlist[bestsuper]->load_super(st, fd, NULL);
1134                 if (rv == 0) {
1135                         superlist[bestsuper]->free_super(st);
1136                         return st;
1137                 }
1138         }
1139         free(st);
1140         return NULL;
1141 }
1142
1143 /* Return size of device in bytes */
1144 int get_dev_size(int fd, char *dname, unsigned long long *sizep)
1145 {
1146         unsigned long long ldsize;
1147         struct stat st;
1148
1149         if (fstat(fd, &st) != -1 && S_ISREG(st.st_mode))
1150                 ldsize = (unsigned long long)st.st_size;
1151         else
1152 #ifdef BLKGETSIZE64
1153         if (ioctl(fd, BLKGETSIZE64, &ldsize) != 0)
1154 #endif
1155         {
1156                 unsigned long dsize;
1157                 if (ioctl(fd, BLKGETSIZE, &dsize) == 0) {
1158                         ldsize = dsize;
1159                         ldsize <<= 9;
1160                 } else {
1161                         if (dname)
1162                                 fprintf(stderr, Name ": Cannot get size of %s: %s\b",
1163                                         dname, strerror(errno));
1164                         return 0;
1165                 }
1166         }
1167         *sizep = ldsize;
1168         return 1;
1169 }
1170
1171
1172 /* Sets endofpart parameter to the last block used by the last GPT partition on the device.
1173  * Returns: 1 if successful
1174  *         -1 for unknown partition type
1175  *          0 for other errors
1176  */
1177 static int get_gpt_last_partition_end(int fd, unsigned long long *endofpart)
1178 {
1179         struct GPT gpt;
1180         unsigned char buf[512];
1181         unsigned char empty_gpt_entry[16]= {0};
1182         struct GPT_part_entry *part;
1183         unsigned long long curr_part_end;
1184         unsigned all_partitions, entry_size;
1185         int part_nr;
1186
1187         *endofpart = 0;
1188
1189         BUILD_BUG_ON(sizeof(gpt) != 512);
1190         /* read GPT header */
1191         lseek(fd, 512, SEEK_SET);
1192         if (read(fd, &gpt, 512) != 512)
1193                 return 0;
1194
1195         /* get the number of partition entries and the entry size */
1196         all_partitions = __le32_to_cpu(gpt.part_cnt);
1197         entry_size = __le32_to_cpu(gpt.part_size);
1198
1199         /* Check GPT signature*/
1200         if (gpt.magic != GPT_SIGNATURE_MAGIC)
1201                 return -1;
1202
1203         /* sanity checks */
1204         if (all_partitions > 1024 ||
1205             entry_size > 512)
1206                 return -1;
1207
1208         /* read first GPT partition entries */
1209         if (read(fd, buf, 512) != 512)
1210                 return 0;
1211
1212         part = (struct GPT_part_entry*)buf;
1213
1214         for (part_nr=0; part_nr < all_partitions; part_nr++) {
1215                 /* is this valid partition? */
1216                 if (memcmp(part->type_guid, empty_gpt_entry, 16) != 0) {
1217                         /* check the last lba for the current partition */
1218                         curr_part_end = __le64_to_cpu(part->ending_lba);
1219                         if (curr_part_end > *endofpart)
1220                                 *endofpart = curr_part_end;
1221                 }
1222
1223                 part = (struct GPT_part_entry*)((unsigned char*)part + entry_size);
1224
1225                 if ((unsigned char *)part >= buf + 512) {
1226                         if (read(fd, buf, 512) != 512)
1227                                 return 0;
1228                         part = (struct GPT_part_entry*)buf;
1229                 }
1230         }
1231         return 1;
1232 }
1233
1234 /* Sets endofpart parameter to the last block used by the last partition on the device.
1235  * Returns: 1 if successful
1236  *         -1 for unknown partition type
1237  *          0 for other errors
1238  */
1239 static int get_last_partition_end(int fd, unsigned long long *endofpart)
1240 {
1241         struct MBR boot_sect;
1242         struct MBR_part_record *part;
1243         unsigned long long curr_part_end;
1244         int part_nr;
1245         int retval = 0;
1246
1247         *endofpart = 0;
1248
1249         BUILD_BUG_ON(sizeof(boot_sect) != 512);
1250         /* read MBR */
1251         lseek(fd, 0, 0);
1252         if (read(fd, &boot_sect, 512) != 512)
1253                 goto abort;
1254
1255         /* check MBP signature */
1256         if (boot_sect.magic == MBR_SIGNATURE_MAGIC) {
1257                 retval = 1;
1258                 /* found the correct signature */
1259                 part = boot_sect.parts;
1260
1261                 for (part_nr=0; part_nr < MBR_PARTITIONS; part_nr++) {
1262                         /* check for GPT type */
1263                         if (part->part_type == MBR_GPT_PARTITION_TYPE) {
1264                                 retval = get_gpt_last_partition_end(fd, endofpart);
1265                                 break;
1266                         }
1267                         /* check the last used lba for the current partition  */
1268                         curr_part_end = __le32_to_cpu(part->first_sect_lba) +
1269                                 __le32_to_cpu(part->blocks_num);
1270                         if (curr_part_end > *endofpart)
1271                                 *endofpart = curr_part_end;
1272
1273                         part++;
1274                 }
1275         } else {
1276                 /* Unknown partition table */
1277                 retval = -1;
1278         }
1279  abort:
1280         return retval;
1281 }
1282
1283 int check_partitions(int fd, char *dname, unsigned long long freesize)
1284 {
1285         /*
1286          * Check where the last partition ends
1287          */
1288         unsigned long long endofpart;
1289         int ret;
1290
1291         if ((ret = get_last_partition_end(fd, &endofpart)) > 0) {
1292                 /* There appears to be a partition table here */
1293                 if (freesize == 0) {
1294                         /* partitions will not be visible in new device */
1295                         fprintf(stderr,
1296                                 Name ": partition table exists on %s but will be lost or\n"
1297                                 "       meaningless after creating array\n",
1298                                 dname);
1299                         return 1;
1300                 } else if (endofpart > freesize) {
1301                         /* last partition overlaps metadata */
1302                         fprintf(stderr,
1303                                 Name ": metadata will over-write last partition on %s.\n",
1304                                 dname);
1305                         return 1;
1306                 }
1307         }
1308         return 0;
1309 }
1310
1311 void get_one_disk(int mdfd, mdu_array_info_t *ainf, mdu_disk_info_t *disk)
1312 {
1313         int d;
1314         ioctl(mdfd, GET_ARRAY_INFO, ainf);
1315         for (d = 0 ; d < ainf->raid_disks + ainf->nr_disks ; d++)
1316                 if (ioctl(mdfd, GET_DISK_INFO, disk) == 0)
1317                         return;
1318 }
1319
1320 int open_container(int fd)
1321 {
1322         /* 'fd' is a block device.  Find out if it is in use
1323          * by a container, and return an open fd on that container.
1324          */
1325         char path[256];
1326         char *e;
1327         DIR *dir;
1328         struct dirent *de;
1329         int dfd, n;
1330         char buf[200];
1331         int major, minor;
1332         struct stat st;
1333
1334         if (fstat(fd, &st) != 0)
1335                 return -1;
1336         sprintf(path, "/sys/dev/block/%d:%d/holders",
1337                 (int)major(st.st_rdev), (int)minor(st.st_rdev));
1338         e = path + strlen(path);
1339
1340         dir = opendir(path);
1341         if (!dir)
1342                 return -1;
1343         while ((de = readdir(dir))) {
1344                 if (de->d_ino == 0)
1345                         continue;
1346                 if (de->d_name[0] == '.')
1347                         continue;
1348                 sprintf(e, "/%s/dev", de->d_name);
1349                 dfd = open(path, O_RDONLY);
1350                 if (dfd < 0)
1351                         continue;
1352                 n = read(dfd, buf, sizeof(buf));
1353                 close(dfd);
1354                 if (n <= 0 || n >= sizeof(buf))
1355                         continue;
1356                 buf[n] = 0;
1357                 if (sscanf(buf, "%d:%d", &major, &minor) != 2)
1358                         continue;
1359                 sprintf(buf, "%d:%d", major, minor);
1360                 dfd = dev_open(buf, O_RDONLY);
1361                 if (dfd >= 0) {
1362                         closedir(dir);
1363                         return dfd;
1364                 }
1365         }
1366         closedir(dir);
1367         return -1;
1368 }
1369
1370 int add_disk(int mdfd, struct supertype *st,
1371              struct mdinfo *sra, struct mdinfo *info)
1372 {
1373         /* Add a device to an array, in one of 2 ways. */
1374         int rv;
1375 #ifndef MDASSEMBLE
1376         if (st->ss->external) {
1377                 if (info->disk.state & (1<<MD_DISK_SYNC))
1378                         info->recovery_start = MaxSector;
1379                 else
1380                         info->recovery_start = 0;
1381                 rv = sysfs_add_disk(sra, info, 0);
1382                 if (! rv) {
1383                         struct mdinfo *sd2;
1384                         for (sd2 = sra->devs; sd2; sd2=sd2->next)
1385                                 if (sd2 == info)
1386                                         break;
1387                         if (sd2 == NULL) {
1388                                 sd2 = malloc(sizeof(*sd2));
1389                                 *sd2 = *info;
1390                                 sd2->next = sra->devs;
1391                                 sra->devs = sd2;
1392                         }
1393                 }
1394         } else
1395 #endif
1396                 rv = ioctl(mdfd, ADD_NEW_DISK, &info->disk);
1397         return rv;
1398 }
1399
1400 int set_array_info(int mdfd, struct supertype *st, struct mdinfo *info)
1401 {
1402         /* Initialise kernel's knowledge of array.
1403          * This varies between externally managed arrays
1404          * and older kernels
1405          */
1406         int vers = md_get_version(mdfd);
1407         int rv;
1408
1409 #ifndef MDASSEMBLE
1410         if (st->ss->external)
1411                 rv = sysfs_set_array(info, vers);
1412         else
1413 #endif
1414                 if ((vers % 100) >= 1) { /* can use different versions */
1415                 mdu_array_info_t inf;
1416                 memset(&inf, 0, sizeof(inf));
1417                 inf.major_version = info->array.major_version;
1418                 inf.minor_version = info->array.minor_version;
1419                 rv = ioctl(mdfd, SET_ARRAY_INFO, &inf);
1420         } else
1421                 rv = ioctl(mdfd, SET_ARRAY_INFO, NULL);
1422         return rv;
1423 }
1424
1425 unsigned long long min_recovery_start(struct mdinfo *array)
1426 {
1427         /* find the minimum recovery_start in an array for metadata
1428          * formats that only record per-array recovery progress instead
1429          * of per-device
1430          */
1431         unsigned long long recovery_start = MaxSector;
1432         struct mdinfo *d;
1433
1434         for (d = array->devs; d; d = d->next)
1435                 recovery_start = min(recovery_start, d->recovery_start);
1436
1437         return recovery_start;
1438 }
1439
1440 char *devnum2devname(int num)
1441 {
1442         char name[100];
1443         if (num >= 0)
1444                 sprintf(name, "md%d", num);
1445         else
1446                 sprintf(name, "md_d%d", -1-num);
1447         return strdup(name);
1448 }
1449
1450 int devname2devnum(char *name)
1451 {
1452         char *ep;
1453         int num;
1454         if (strncmp(name, "md_d", 4)==0)
1455                 num = -1-strtoul(name+4, &ep, 10);
1456         else
1457                 num = strtoul(name+2, &ep, 10);
1458         return num;
1459 }
1460
1461 int stat2devnum(struct stat *st)
1462 {
1463         char path[30];
1464         char link[200];
1465         char *cp;
1466         int n;
1467
1468         if ((S_IFMT & st->st_mode) == S_IFBLK) {
1469                 if (major(st->st_rdev) == MD_MAJOR)
1470                         return minor(st->st_rdev);
1471                 else if (major(st->st_rdev) == get_mdp_major())
1472                         return -1- (minor(st->st_rdev)>>MdpMinorShift);
1473
1474                 /* must be an extended-minor partition. Look at the
1475                  * /sys/dev/block/%d:%d link which must look like
1476                  * ../../block/mdXXX/mdXXXpYY
1477                  */
1478                 sprintf(path, "/sys/dev/block/%d:%d", major(st->st_rdev),
1479                         minor(st->st_rdev));
1480                 n = readlink(path, link, sizeof(link)-1);
1481                 if (n <= 0)
1482                         return NoMdDev;
1483                 link[n] = 0;
1484                 cp = strrchr(link, '/');
1485                 if (cp) *cp = 0;
1486                 cp = strchr(link, '/');
1487                 if (cp && strncmp(cp, "/md", 3) == 0)
1488                         return devname2devnum(cp+1);
1489         }
1490         return NoMdDev;
1491
1492 }
1493
1494 int fd2devnum(int fd)
1495 {
1496         struct stat stb;
1497         if (fstat(fd, &stb) == 0)
1498                 return stat2devnum(&stb);
1499         return NoMdDev;
1500 }
1501
1502 char *pid_dir = VAR_RUN;
1503
1504 int mdmon_pid(int devnum)
1505 {
1506         char path[100];
1507         char pid[10];
1508         int fd;
1509         int n;
1510         sprintf(path, "%s/%s.pid", pid_dir, devnum2devname(devnum));
1511         fd = open(path, O_RDONLY | O_NOATIME, 0);
1512
1513         if (fd < 0)
1514                 return -1;
1515         n = read(fd, pid, 9);
1516         close(fd);
1517         if (n <= 0)
1518                 return -1;
1519         return atoi(pid);
1520 }
1521
1522 int mdmon_running(int devnum)
1523 {
1524         int pid = mdmon_pid(devnum);
1525         if (pid <= 0)
1526                 return 0;
1527         if (kill(pid, 0) == 0)
1528                 return 1;
1529         return 0;
1530 }
1531
1532 int start_mdmon(int devnum)
1533 {
1534         int i;
1535         int len;
1536         pid_t pid;
1537         int status;
1538         char pathbuf[1024];
1539         char *paths[4] = {
1540                 pathbuf,
1541                 "/sbin/mdmon",
1542                 "mdmon",
1543                 NULL
1544         };
1545
1546         if (check_env("MDADM_NO_MDMON"))
1547                 return 0;
1548
1549         len = readlink("/proc/self/exe", pathbuf, sizeof(pathbuf));
1550         if (len > 0) {
1551                 char *sl;
1552                 pathbuf[len] = 0;
1553                 sl = strrchr(pathbuf, '/');
1554                 if (sl)
1555                         sl++;
1556                 else
1557                         sl = pathbuf;
1558                 strcpy(sl, "mdmon");
1559         } else
1560                 pathbuf[0] = '\0';
1561
1562         switch(fork()) {
1563         case 0:
1564                 /* FIXME yuk. CLOSE_EXEC?? */
1565                 for (i=3; i < 100; i++)
1566                         close(i);
1567                 for (i=0; paths[i]; i++)
1568                         if (paths[i][0])
1569                                 execl(paths[i], "mdmon",
1570                                       devnum2devname(devnum),
1571                                       NULL);
1572                 exit(1);
1573         case -1: fprintf(stderr, Name ": cannot run mdmon. "
1574                          "Array remains readonly\n");
1575                 return -1;
1576         default: /* parent - good */
1577                 pid = wait(&status);
1578                 if (pid < 0 || status != 0)
1579                         return -1;
1580         }
1581         return 0;
1582 }
1583
1584 int check_env(char *name)
1585 {
1586         char *val = getenv(name);
1587
1588         if (val && atoi(val) == 1)
1589                 return 1;
1590
1591         return 0;
1592 }
1593
1594 __u32 random32(void)
1595 {
1596         __u32 rv;
1597         int rfd = open("/dev/urandom", O_RDONLY);
1598         if (rfd < 0 || read(rfd, &rv, 4) != 4)
1599                 rv = random();
1600         if (rfd >= 0)
1601                 close(rfd);
1602         return rv;
1603 }
1604
1605 #ifndef MDASSEMBLE
1606 int flush_metadata_updates(struct supertype *st)
1607 {
1608         int sfd;
1609         if (!st->updates) {
1610                 st->update_tail = NULL;
1611                 return -1;
1612         }
1613
1614         sfd = connect_monitor(devnum2devname(st->container_dev));
1615         if (sfd < 0)
1616                 return -1;
1617
1618         while (st->updates) {
1619                 struct metadata_update *mu = st->updates;
1620                 st->updates = mu->next;
1621
1622                 send_message(sfd, mu, 0);
1623                 wait_reply(sfd, 0);
1624                 free(mu->buf);
1625                 free(mu);
1626         }
1627         ack(sfd, 0);
1628         wait_reply(sfd, 0);
1629         close(sfd);
1630         st->update_tail = NULL;
1631         return 0;
1632 }
1633
1634 void append_metadata_update(struct supertype *st, void *buf, int len)
1635 {
1636
1637         struct metadata_update *mu = malloc(sizeof(*mu));
1638
1639         mu->buf = buf;
1640         mu->len = len;
1641         mu->space = NULL;
1642         mu->next = NULL;
1643         *st->update_tail = mu;
1644         st->update_tail = &mu->next;
1645 }
1646 #endif /* MDASSEMBLE */
1647
1648 #ifdef __TINYC__
1649 /* tinyc doesn't optimize this check in ioctl.h out ... */
1650 unsigned int __invalid_size_argument_for_IOC = 0;
1651 #endif
1652