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 /*
  69  * Parse a 128 bit uuid in 4 integers
  70  * format is 32 hexx nibbles with options :.<space> separator
  71  * If not exactly 32 hex digits are found, return 0
  72  * else return 1
  73  */
  74 int parse_uuid(char *str, int uuid[4])
  75 {
  76         int hit = 0; /* number of Hex digIT */
  77         int i;
  78         char c;
  79         for (i=0; i<4; i++) uuid[i]=0;
  80
  81         while ((c= *str++)) {
  82                 int n;
  83                 if (c>='0' && c<='9')
  84                         n = c-'0';
  85                 else if (c>='a' && c <= 'f')
  86                         n = 10 + c - 'a';
  87                 else if (c>='A' && c <= 'F')
  88                         n = 10 + c - 'A';
  89                 else if (strchr(":. -", c))
  90                         continue;
  91                 else return 0;
  92
  93                 if (hit<32) {
  94                         uuid[hit/8] <<= 4;
  95                         uuid[hit/8] += n;
  96                 }
  97                 hit++;
  98         }
  99         if (hit == 32)
 100                 return 1;
 101         return 0;
 102 }
 103
 104
 105 /*
 106  * Get the md version number.
 107  * We use the RAID_VERSION ioctl if it is supported
 108  * If not, but we have a block device with major '9', we assume
 109  * 0.36.0
 110  *
 111  * Return version number as 24 but number - assume version parts
 112  * always < 255
 113  */
 114
 115 int md_get_version(int fd)
 116 {
 117     struct stat stb;
 118     mdu_version_t vers;
 119
 120     if (fstat(fd, &stb)<0)
 121         return -1;
 122     if ((S_IFMT&stb.st_mode) != S_IFBLK)
 123         return -1;
 124
 125     if (ioctl(fd, RAID_VERSION, &vers) == 0)
 126         return  (vers.major*10000) + (vers.minor*100) + vers.patchlevel;
 127     if (errno == EACCES)
 128             return -1;
 129     if (major(stb.st_rdev) == MD_MAJOR)
 130         return (3600);
 131     return -1;
 132 }
 133
 134 int get_linux_version()
 135 {
 136         struct utsname name;
 137         char *cp;
 138         int a,b,c;
 139         if (uname(&name) <0)
 140                 return -1;
 141
 142         cp = name.release;
 143         a = strtoul(cp, &cp, 10);
 144         if (*cp != '.') return -1;
 145         b = strtoul(cp+1, &cp, 10);
 146         if (*cp != '.') return -1;
 147         c = strtoul(cp+1, NULL, 10);
 148
 149         return (a*1000000)+(b*1000)+c;
 150 }
 151
 152 void remove_partitions(int fd)
 153 {
 154         /* remove partitions from this block devices.
 155          * This is used for components added to an array
 156          */
 157 #ifdef BLKPG_DEL_PARTITION
 158         struct blkpg_ioctl_arg a;
 159         struct blkpg_partition p;
 160
 161         a.op = BLKPG_DEL_PARTITION;
 162         a.data = (void*)&p;
 163         a.datalen = sizeof(p);
 164         a.flags = 0;
 165         memset(a.data, 0, a.datalen);
 166         for (p.pno=0; p.pno < 16; p.pno++)
 167                 ioctl(fd, BLKPG, &a);
 168 #endif
 169 }
 170
 171 int enough(int level, int raid_disks, int layout, int clean,
 172            char *avail, int avail_disks)
 173 {
 174         int copies, first;
 175         switch (level) {
 176         case 10:
 177                 /* This is the tricky one - we need to check
 178                  * which actual disks are present.
 179                  */
 180                 copies = (layout&255)* ((layout>>8) & 255);
 181                 first=0;
 182                 do {
 183                         /* there must be one of the 'copies' form 'first' */
 184                         int n = copies;
 185                         int cnt=0;
 186                         while (n--) {
 187                                 if (avail[first])
 188                                         cnt++;
 189                                 first = (first+1) % raid_disks;
 190                         }
 191                         if (cnt == 0)
 192                                 return 0;
 193
 194                 } while (first != 0);
 195                 return 1;
 196
 197         case -4:
 198                 return avail_disks>= 1;
 199         case -1:
 200         case 0:
 201                 return avail_disks == raid_disks;
 202         case 1:
 203                 return avail_disks >= 1;
 204         case 4:
 205         case 5:
 206                 if (clean)
 207                         return avail_disks >= raid_disks-1;
 208                 else
 209                         return avail_disks >= raid_disks;
 210         case 6:
 211                 if (clean)
 212                         return avail_disks >= raid_disks-2;
 213                 else
 214                         return avail_disks >= raid_disks;
 215         default:
 216                 return 0;
 217         }
 218 }
 219
 220 const int uuid_match_any[4] = { ~0, ~0, ~0, ~0 };
 221 int same_uuid(int a[4], int b[4], int swapuuid)
 222 {
 223         if (memcmp(a, uuid_match_any, sizeof(int[4])) == 0 ||
 224             memcmp(b, uuid_match_any, sizeof(int[4])) == 0)
 225                 return 1;
 226
 227         if (swapuuid) {
 228                 /* parse uuids are hostendian.
 229                  * uuid's from some superblocks are big-ending
 230                  * if there is a difference, we need to swap..
 231                  */
 232                 unsigned char *ac = (unsigned char *)a;
 233                 unsigned char *bc = (unsigned char *)b;
 234                 int i;
 235                 for (i=0; i<16; i+= 4) {
 236                         if (ac[i+0] != bc[i+3] ||
 237                             ac[i+1] != bc[i+2] ||
 238                             ac[i+2] != bc[i+1] ||
 239                             ac[i+3] != bc[i+0])
 240                                 return 0;
 241                 }
 242                 return 1;
 243         } else {
 244                 if (a[0]==b[0] &&
 245                     a[1]==b[1] &&
 246                     a[2]==b[2] &&
 247                     a[3]==b[3])
 248                         return 1;
 249                 return 0;
 250         }
 251 }
 252 void copy_uuid(void *a, int b[4], int swapuuid)
 253 {
 254         if (swapuuid) {
 255                 /* parse uuids are hostendian.
 256                  * uuid's from some superblocks are big-ending
 257                  * if there is a difference, we need to swap..
 258                  */
 259                 unsigned char *ac = (unsigned char *)a;
 260                 unsigned char *bc = (unsigned char *)b;
 261                 int i;
 262                 for (i=0; i<16; i+= 4) {
 263                         ac[i+0] = bc[i+3];
 264                         ac[i+1] = bc[i+2];
 265                         ac[i+2] = bc[i+1];
 266                         ac[i+3] = bc[i+0];
 267                 }
 268         } else
 269                 memcpy(a, b, 16);
 270 }
 271
 272 char *fname_from_uuid(struct supertype *st, struct mdinfo *info, char *buf, char sep)
 273 {
 274         int i, j;
 275         int id;
 276         char uuid[16];
 277         char *c = buf;
 278         strcpy(c, "UUID-");
 279         c += strlen(c);
 280         copy_uuid(uuid, info->uuid, st->ss->swapuuid);
 281         for (i = 0; i < 4; i++) {
 282                 id = uuid[i];
 283                 if (i)
 284                         *c++ = sep;
 285                 for (j = 3; j >= 0; j--) {
 286                         sprintf(c,"%02x", (unsigned char) uuid[j+4*i]);
 287                         c+= 2;
 288                 }
 289         }
 290         return buf;
 291 }
 292
 293 #ifndef MDASSEMBLE
 294 int check_ext2(int fd, char *name)
 295 {
 296         /*
 297          * Check for an ext2fs file system.
 298          * Superblock is always 1K at 1K offset
 299          *
 300          * s_magic is le16 at 56 == 0xEF53
 301          * report mtime - le32 at 44
 302          * blocks - le32 at 4
 303          * logblksize - le32 at 24
 304          */
 305         unsigned char sb[1024];
 306         time_t mtime;
 307         int size, bsize;
 308         if (lseek(fd, 1024,0)!= 1024)
 309                 return 0;
 310         if (read(fd, sb, 1024)!= 1024)
 311                 return 0;
 312         if (sb[56] != 0x53 || sb[57] != 0xef)
 313                 return 0;
 314
 315         mtime = sb[44]|(sb[45]|(sb[46]|sb[47]<<8)<<8)<<8;
 316         bsize = sb[24]|(sb[25]|(sb[26]|sb[27]<<8)<<8)<<8;
 317         size = sb[4]|(sb[5]|(sb[6]|sb[7]<<8)<<8)<<8;
 318         fprintf(stderr, Name ": %s appears to contain an ext2fs file system\n",
 319                 name);
 320         fprintf(stderr,"    size=%dK  mtime=%s",
 321                 size*(1<<bsize), ctime(&mtime));
 322         return 1;
 323 }
 324
 325 int check_reiser(int fd, char *name)
 326 {
 327         /*
 328          * superblock is at 64K
 329          * size is 1024;
 330          * Magic string "ReIsErFs" or "ReIsEr2Fs" at 52
 331          *
 332          */
 333         unsigned char sb[1024];
 334         unsigned long size;
 335         if (lseek(fd, 64*1024, 0) != 64*1024)
 336                 return 0;
 337         if (read(fd, sb, 1024) != 1024)
 338                 return 0;
 339         if (strncmp((char*)sb+52, "ReIsErFs",8)!=0 &&
 340             strncmp((char*)sb+52, "ReIsEr2Fs",9)!=0)
 341                 return 0;
 342         fprintf(stderr, Name ": %s appears to contain a reiserfs file system\n",name);
 343         size = sb[0]|(sb[1]|(sb[2]|sb[3]<<8)<<8)<<8;
 344         fprintf(stderr, "    size = %luK\n", size*4);
 345
 346         return 1;
 347 }
 348
 349 int check_raid(int fd, char *name)
 350 {
 351         struct mdinfo info;
 352         time_t crtime;
 353         char *level;
 354         struct supertype *st = guess_super(fd);
 355
 356         if (!st) return 0;
 357         st->ss->load_super(st, fd, name);
 358         /* Looks like a raid array .. */
 359         fprintf(stderr, Name ": %s appears to be part of a raid array:\n",
 360                 name);
 361         st->ss->getinfo_super(st, &info);
 362         st->ss->free_super(st);
 363         crtime = info.array.ctime;
 364         level = map_num(pers, info.array.level);
 365         if (!level) level = "-unknown-";
 366         fprintf(stderr, "    level=%s devices=%d ctime=%s",
 367                 level, info.array.raid_disks, ctime(&crtime));
 368         return 1;
 369 }
 370
 371 int ask(char *mesg)
 372 {
 373         char *add = "";
 374         int i;
 375         for (i=0; i<5; i++) {
 376                 char buf[100];
 377                 fprintf(stderr, "%s%s", mesg, add);
 378                 fflush(stderr);
 379                 if (fgets(buf, 100, stdin)==NULL)
 380                         return 0;
 381                 if (buf[0]=='y' || buf[0]=='Y')
 382                         return 1;
 383                 if (buf[0]=='n' || buf[0]=='N')
 384                         return 0;
 385                 add = "(y/n) ";
 386         }
 387         fprintf(stderr, Name ": assuming 'no'\n");
 388         return 0;
 389 }
 390 #endif /* MDASSEMBLE */
 391
 392 char *map_num(mapping_t *map, int num)
 393 {
 394         while (map->name) {
 395                 if (map->num == num)
 396                         return map->name;
 397                 map++;
 398         }
 399         return NULL;
 400 }
 401
 402 int map_name(mapping_t *map, char *name)
 403 {
 404         while (map->name) {
 405                 if (strcmp(map->name, name)==0)
 406                         return map->num;
 407                 map++;
 408         }
 409         return UnSet;
 410 }
 411
 412
 413 int is_standard(char *dev, int *nump)
 414 {
 415         /* tests if dev is a "standard" md dev name.
 416          * i.e if the last component is "/dNN" or "/mdNN",
 417          * where NN is a string of digits
 418          * Returns 1 if a partitionable standard,
 419          *   -1 if non-partitonable,
 420          *   0 if not a standard name.
 421          */
 422         char *d = strrchr(dev, '/');
 423         int type=0;
 424         int num;
 425         if (!d)
 426                 return 0;
 427         if (strncmp(d, "/d",2)==0)
 428                 d += 2, type=1; /* /dev/md/dN{pM} */
 429         else if (strncmp(d, "/md_d", 5)==0)
 430                 d += 5, type=1; /* /dev/md_dN{pM} */
 431         else if (strncmp(d, "/md", 3)==0)
 432                 d += 3, type=-1; /* /dev/mdN */
 433         else if (d-dev > 3 && strncmp(d-2, "md/", 3)==0)
 434                 d += 1, type=-1; /* /dev/md/N */
 435         else
 436                 return 0;
 437         if (!*d)
 438                 return 0;
 439         num = atoi(d);
 440         while (isdigit(*d))
 441                 d++;
 442         if (*d)
 443                 return 0;
 444         if (nump) *nump = num;
 445
 446         return type;
 447 }
 448
 449
 450 /*
 451  * convert a major/minor pair for a block device into a name in /dev, if possible.
 452  * On the first call, walk /dev collecting name.
 453  * Put them in a simple linked listfor now.
 454  */
 455 struct devmap {
 456     int major, minor;
 457     char *name;
 458     struct devmap *next;
 459 } *devlist = NULL;
 460 int devlist_ready = 0;
 461
 462 int add_dev(const char *name, const struct stat *stb, int flag, struct FTW *s)
 463 {
 464         struct stat st;
 465
 466         if (S_ISLNK(stb->st_mode)) {
 467                 if (stat(name, &st) != 0)
 468                         return 0;
 469                 stb = &st;
 470         }
 471
 472         if ((stb->st_mode&S_IFMT)== S_IFBLK) {
 473                 char *n = strdup(name);
 474                 struct devmap *dm = malloc(sizeof(*dm));
 475                 if (strncmp(n, "/dev/./", 7)==0)
 476                         strcpy(n+4, name+6);
 477                 if (dm) {
 478                         dm->major = major(stb->st_rdev);
 479                         dm->minor = minor(stb->st_rdev);
 480                         dm->name = n;
 481                         dm->next = devlist;
 482                         devlist = dm;
 483                 }
 484         }
 485         return 0;
 486 }
 487
 488 #ifndef HAVE_NFTW
 489 #ifdef HAVE_FTW
 490 int add_dev_1(const char *name, const struct stat *stb, int flag)
 491 {
 492         return add_dev(name, stb, flag, NULL);
 493 }
 494 int nftw(const char *path, int (*han)(const char *name, const struct stat *stb, int flag, struct FTW *s), int nopenfd, int flags)
 495 {
 496         return ftw(path, add_dev_1, nopenfd);
 497 }
 498 #else
 499 int nftw(const char *path, int (*han)(const char *name, const struct stat *stb, int flag, struct FTW *s), int nopenfd, int flags)
 500 {
 501         return 0;
 502 }
 503 #endif /* HAVE_FTW */
 504 #endif /* HAVE_NFTW */
 505
 506 /*
 507  * Find a block device with the right major/minor number.
 508  * If we find multiple names, choose the shortest.
 509  * If we find a name in /dev/md/, we prefer that.
 510  * This applies only to names for MD devices.
 511  */
 512 char *map_dev(int major, int minor, int create)
 513 {
 514         struct devmap *p;
 515         char *regular = NULL, *preferred=NULL;
 516         int did_check = 0;
 517
 518         if (major == 0 && minor == 0)
 519                         return NULL;
 520
 521  retry:
 522         if (!devlist_ready) {
 523                 char *dev = "/dev";
 524                 struct stat stb;
 525                 while(devlist) {
 526                         struct devmap *d = devlist;
 527                         devlist = d->next;
 528                         free(d->name);
 529                         free(d);
 530                 }
 531                 if (lstat(dev, &stb)==0 &&
 532                     S_ISLNK(stb.st_mode))
 533                         dev = "/dev/.";
 534                 nftw(dev, add_dev, 10, FTW_PHYS);
 535                 devlist_ready=1;
 536                 did_check = 1;
 537         }
 538
 539         for (p=devlist; p; p=p->next)
 540                 if (p->major == major &&
 541                     p->minor == minor) {
 542                         if (strncmp(p->name, "/dev/md/",8) == 0) {
 543                                 if (preferred == NULL ||
 544                                     strlen(p->name) < strlen(preferred))
 545                                         preferred = p->name;
 546                         } else {
 547                                 if (regular == NULL ||
 548                                     strlen(p->name) < strlen(regular))
 549                                         regular = p->name;
 550                         }
 551                 }
 552         if (!regular && !preferred && !did_check) {
 553                 devlist_ready = 0;
 554                 goto retry;
 555         }
 556         if (create && !regular && !preferred) {
 557                 static char buf[30];
 558                 snprintf(buf, sizeof(buf), "%d:%d", major, minor);
 559                 regular = buf;
 560         }
 561
 562         return preferred ? preferred : regular;
 563 }
 564
 565 unsigned long calc_csum(void *super, int bytes)
 566 {
 567         unsigned long long newcsum = 0;
 568         int i;
 569         unsigned int csum;
 570         unsigned int *superc = (unsigned int*) super;
 571
 572         for(i=0; i<bytes/4; i++)
 573                 newcsum+= superc[i];
 574         csum = (newcsum& 0xffffffff) + (newcsum>>32);
 575 #ifdef __alpha__
 576 /* The in-kernel checksum calculation is always 16bit on
 577  * the alpha, though it is 32 bit on i386...
 578  * I wonder what it is elsewhere... (it uses and API in
 579  * a way that it shouldn't).
 580  */
 581         csum = (csum & 0xffff) + (csum >> 16);
 582         csum = (csum & 0xffff) + (csum >> 16);
 583 #endif
 584         return csum;
 585 }
 586
 587 #ifndef MDASSEMBLE
 588 char *human_size(long long bytes)
 589 {
 590         static char buf[30];
 591
 592         /* We convert bytes to either centi-M{ega,ibi}bytes or
 593          * centi-G{igi,ibi}bytes, with appropriate rounding,
 594          * and then print 1/100th of those as a decimal.
 595          * We allow upto 2048Megabytes before converting to
 596          * gigabytes, as that shows more precision and isn't
 597          * too large a number.
 598          * Terrabytes are not yet handled.
 599          */
 600
 601         if (bytes < 5000*1024)
 602                 buf[0]=0;
 603         else if (bytes < 2*1024LL*1024LL*1024LL) {
 604                 long cMiB = (bytes / ( (1LL<<20) / 200LL ) +1) /2;
 605                 long cMB  = (bytes / ( 1000000LL / 200LL ) +1) /2;
 606                 snprintf(buf, sizeof(buf), " (%ld.%02ld MiB %ld.%02ld MB)",
 607                         cMiB/100 , cMiB % 100,
 608                         cMB/100, cMB % 100);
 609         } else {
 610                 long cGiB = (bytes / ( (1LL<<30) / 200LL ) +1) /2;
 611                 long cGB  = (bytes / (1000000000LL/200LL ) +1) /2;
 612                 snprintf(buf, sizeof(buf), " (%ld.%02ld GiB %ld.%02ld GB)",
 613                         cGiB/100 , cGiB % 100,
 614                         cGB/100, cGB % 100);
 615         }
 616         return buf;
 617 }
 618
 619 char *human_size_brief(long long bytes)
 620 {
 621         static char buf[30];
 622
 623         if (bytes < 5000*1024)
 624                 snprintf(buf, sizeof(buf), "%ld.%02ldKiB",
 625                         (long)(bytes>>10), (long)(((bytes&1023)*100+512)/1024)
 626                         );
 627         else if (bytes < 2*1024LL*1024LL*1024LL)
 628                 snprintf(buf, sizeof(buf), "%ld.%02ldMiB",
 629                         (long)(bytes>>20),
 630                         (long)((bytes&0xfffff)+0x100000/200)/(0x100000/100)
 631                         );
 632         else
 633                 snprintf(buf, sizeof(buf), "%ld.%02ldGiB",
 634                         (long)(bytes>>30),
 635                         (long)(((bytes>>10)&0xfffff)+0x100000/200)/(0x100000/100)
 636                         );
 637         return buf;
 638 }
 639
 640 void print_r10_layout(int layout)
 641 {
 642         int near = layout & 255;
 643         int far = (layout >> 8) & 255;
 644         int offset = (layout&0x10000);
 645         char *sep = "";
 646
 647         if (near != 1) {
 648                 printf("%s near=%d", sep, near);
 649                 sep = ",";
 650         }
 651         if (far != 1)
 652                 printf("%s %s=%d", sep, offset?"offset":"far", far);
 653         if (near*far == 1)
 654                 printf("NO REDUNDANCY");
 655 }
 656 #endif
 657
 658 unsigned long long calc_array_size(int level, int raid_disks, int layout,
 659                                    int chunksize, unsigned long long devsize)
 660 {
 661         int data_disks = 0;
 662         switch (level) {
 663         case 0: data_disks = raid_disks; break;
 664         case 1: data_disks = 1; break;
 665         case 4:
 666         case 5: data_disks = raid_disks - 1; break;
 667         case 6: data_disks = raid_disks - 2; break;
 668         case 10: data_disks = raid_disks / (layout & 255) / ((layout>>8)&255);
 669                 break;
 670         }
 671         devsize &= ~(unsigned long long)((chunksize>>9)-1);
 672         return data_disks * devsize;
 673 }
 674
 675 int get_mdp_major(void)
 676 {
 677 static int mdp_major = -1;
 678         FILE *fl;
 679         char *w;
 680         int have_block = 0;
 681         int have_devices = 0;
 682         int last_num = -1;
 683
 684         if (mdp_major != -1)
 685                 return mdp_major;
 686         fl = fopen("/proc/devices", "r");
 687         if (!fl)
 688                 return -1;
 689         while ((w = conf_word(fl, 1))) {
 690                 if (have_block && strcmp(w, "devices:")==0)
 691                         have_devices = 1;
 692                 have_block =  (strcmp(w, "Block")==0);
 693                 if (isdigit(w[0]))
 694                         last_num = atoi(w);
 695                 if (have_devices && strcmp(w, "mdp")==0)
 696                         mdp_major = last_num;
 697                 free(w);
 698         }
 699         fclose(fl);
 700         return mdp_major;
 701 }
 702
 703 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
 704 char *get_md_name(int dev)
 705 {
 706         /* find /dev/md%d or /dev/md/%d or make a device /dev/.tmp.md%d */
 707         /* if dev < 0, want /dev/md/d%d or find mdp in /proc/devices ... */
 708         static char devname[50];
 709         struct stat stb;
 710         dev_t rdev;
 711         char *dn;
 712
 713         if (dev < 0) {
 714                 int mdp =  get_mdp_major();
 715                 if (mdp < 0) return NULL;
 716                 rdev = makedev(mdp, (-1-dev)<<6);
 717                 snprintf(devname, sizeof(devname), "/dev/md/d%d", -1-dev);
 718                 if (stat(devname, &stb) == 0
 719                     && (S_IFMT&stb.st_mode) == S_IFBLK
 720                     && (stb.st_rdev == rdev))
 721                         return devname;
 722         } else {
 723                 rdev = makedev(MD_MAJOR, dev);
 724                 snprintf(devname, sizeof(devname), "/dev/md%d", dev);
 725                 if (stat(devname, &stb) == 0
 726                     && (S_IFMT&stb.st_mode) == S_IFBLK
 727                     && (stb.st_rdev == rdev))
 728                         return devname;
 729
 730                 snprintf(devname, sizeof(devname), "/dev/md/%d", dev);
 731                 if (stat(devname, &stb) == 0
 732                     && (S_IFMT&stb.st_mode) == S_IFBLK
 733                     && (stb.st_rdev == rdev))
 734                         return devname;
 735         }
 736         dn = map_dev(major(rdev), minor(rdev), 0);
 737         if (dn)
 738                 return dn;
 739         snprintf(devname, sizeof(devname), "/dev/.tmp.md%d", dev);
 740         if (mknod(devname, S_IFBLK | 0600, rdev) == -1)
 741                 if (errno != EEXIST)
 742                         return NULL;
 743
 744         if (stat(devname, &stb) == 0
 745             && (S_IFMT&stb.st_mode) == S_IFBLK
 746             && (stb.st_rdev == rdev))
 747                 return devname;
 748         unlink(devname);
 749         return NULL;
 750 }
 751
 752 void put_md_name(char *name)
 753 {
 754         if (strncmp(name, "/dev/.tmp.md", 12)==0)
 755                 unlink(name);
 756 }
 757
 758 int find_free_devnum(int use_partitions)
 759 {
 760         int devnum;
 761         for (devnum = 127; devnum != 128;
 762              devnum = devnum ? devnum-1 : (1<<20)-1) {
 763                 char *dn;
 764                 int _devnum;
 765
 766                 _devnum = use_partitions ? (-1-devnum) : devnum;
 767                 if (mddev_busy(_devnum))
 768                         continue;
 769                 /* make sure it is new to /dev too, at least as a
 770                  * non-standard */
 771                 dn = map_dev(dev2major(_devnum), dev2minor(_devnum), 0);
 772                 if (dn && ! is_standard(dn, NULL))
 773                         continue;
 774                 break;
 775         }
 776         if (devnum == 128)
 777                 return NoMdDev;
 778         return use_partitions ? (-1-devnum) : devnum;
 779 }
 780 #endif /* !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO) */
 781
 782 int dev_open(char *dev, int flags)
 783 {
 784         /* like 'open', but if 'dev' matches %d:%d, create a temp
 785          * block device and open that
 786          */
 787         char *e;
 788         int fd = -1;
 789         char devname[32];
 790         int major;
 791         int minor;
 792
 793         if (!dev) return -1;
 794
 795         major = strtoul(dev, &e, 0);
 796         if (e > dev && *e == ':' && e[1] &&
 797             (minor = strtoul(e+1, &e, 0)) >= 0 &&
 798             *e == 0) {
 799                 snprintf(devname, sizeof(devname), "/dev/.tmp.md.%d:%d:%d",
 800                          (int)getpid(), major, minor);
 801                 if (mknod(devname, S_IFBLK|0600, makedev(major, minor))==0) {
 802                         fd = open(devname, flags|O_DIRECT);
 803                         unlink(devname);
 804                 }
 805         } else
 806                 fd = open(dev, flags|O_DIRECT);
 807         return fd;
 808 }
 809
 810 int open_dev(int devnum)
 811 {
 812         char buf[20];
 813
 814         sprintf(buf, "%d:%d", dev2major(devnum), dev2minor(devnum));
 815         return dev_open(buf, O_RDWR);
 816 }
 817
 818 int open_dev_excl(int devnum)
 819 {
 820         char buf[20];
 821         int i;
 822
 823         sprintf(buf, "%d:%d", dev2major(devnum), dev2minor(devnum));
 824         for (i=0 ; i<25 ; i++) {
 825                 int fd = dev_open(buf, O_RDWR|O_EXCL);
 826                 if (fd >= 0)
 827                         return fd;
 828                 if (errno != EBUSY)
 829                         return fd;
 830                 usleep(200000);
 831         }
 832         return -1;
 833 }
 834
 835 int same_dev(char *one, char *two)
 836 {
 837         struct stat st1, st2;
 838         if (stat(one, &st1) != 0)
 839                 return 0;
 840         if (stat(two, &st2) != 0)
 841                 return 0;
 842         if ((st1.st_mode & S_IFMT) != S_IFBLK)
 843                 return 0;
 844         if ((st2.st_mode & S_IFMT) != S_IFBLK)
 845                 return 0;
 846         return st1.st_rdev == st2.st_rdev;
 847 }
 848
 849 void wait_for(char *dev, int fd)
 850 {
 851         int i;
 852         struct stat stb_want;
 853
 854         if (fstat(fd, &stb_want) != 0 ||
 855             (stb_want.st_mode & S_IFMT) != S_IFBLK)
 856                 return;
 857
 858         for (i=0 ; i<25 ; i++) {
 859                 struct stat stb;
 860                 if (stat(dev, &stb) == 0 &&
 861                     (stb.st_mode & S_IFMT) == S_IFBLK &&
 862                     (stb.st_rdev == stb_want.st_rdev))
 863                         return;
 864                 usleep(200000);
 865         }
 866 }
 867
 868 struct superswitch *superlist[] = { &super0, &super1, &super_ddf, &super_imsm, NULL };
 869
 870 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
 871
 872 struct supertype *super_by_fd(int fd)
 873 {
 874         mdu_array_info_t array;
 875         int vers;
 876         int minor;
 877         struct supertype *st = NULL;
 878         struct mdinfo *sra;
 879         char *verstr;
 880         char version[20];
 881         int i;
 882         char *subarray = NULL;
 883
 884         sra = sysfs_read(fd, 0, GET_VERSION);
 885
 886         if (sra) {
 887                 vers = sra->array.major_version;
 888                 minor = sra->array.minor_version;
 889                 verstr = sra->text_version;
 890         } else {
 891                 if (ioctl(fd, GET_ARRAY_INFO, &array))
 892                         array.major_version = array.minor_version = 0;
 893                 vers = array.major_version;
 894                 minor = array.minor_version;
 895                 verstr = "";
 896         }
 897
 898         if (vers != -1) {
 899                 sprintf(version, "%d.%d", vers, minor);
 900                 verstr = version;
 901         }
 902         if (minor == -2 && is_subarray(verstr)) {
 903                 char *dev = verstr+1;
 904                 subarray = strchr(dev, '/');
 905                 int devnum;
 906                 if (subarray)
 907                         *subarray++ = '\0';
 908                 devnum = devname2devnum(dev);
 909                 subarray = strdup(subarray);
 910                 if (sra)
 911                         sysfs_free(sra);
 912                 sra = sysfs_read(-1, devnum, GET_VERSION);
 913                 if (sra && sra->text_version[0])
 914                         verstr = sra->text_version;
 915                 else
 916                         verstr = "-no-metadata-";
 917         }
 918
 919         for (i = 0; st == NULL && superlist[i] ; i++)
 920                 st = superlist[i]->match_metadata_desc(verstr);
 921
 922         if (sra)
 923                 sysfs_free(sra);
 924         if (st) {
 925                 st->sb = NULL;
 926                 if (subarray) {
 927                         strncpy(st->subarray, subarray, 32);
 928                         st->subarray[31] = 0;
 929                         free(subarray);
 930                 } else
 931                         st->subarray[0] = 0;
 932         }
 933         return st;
 934 }
 935 #endif /* !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO) */
 936
 937
 938 struct supertype *dup_super(struct supertype *orig)
 939 {
 940         struct supertype *st;
 941
 942         if (!orig)
 943                 return orig;
 944         st = malloc(sizeof(*st));
 945         if (!st)
 946                 return st;
 947         memset(st, 0, sizeof(*st));
 948         st->ss = orig->ss;
 949         st->max_devs = orig->max_devs;
 950         st->minor_version = orig->minor_version;
 951         strcpy(st->subarray, orig->subarray);
 952         st->sb = NULL;
 953         st->info = NULL;
 954         return st;
 955 }
 956
 957 struct supertype *guess_super(int fd)
 958 {
 959         /* try each load_super to find the best match,
 960          * and return the best superswitch
 961          */
 962         struct superswitch  *ss;
 963         struct supertype *st;
 964         unsigned long besttime = 0;
 965         int bestsuper = -1;
 966         int i;
 967
 968         st = malloc(sizeof(*st));
 969         for (i=0 ; superlist[i]; i++) {
 970                 int rv;
 971                 ss = superlist[i];
 972                 memset(st, 0, sizeof(*st));
 973                 rv = ss->load_super(st, fd, NULL);
 974                 if (rv == 0) {
 975                         struct mdinfo info;
 976                         st->ss->getinfo_super(st, &info);
 977                         if (bestsuper == -1 ||
 978                             besttime < info.array.ctime) {
 979                                 bestsuper = i;
 980                                 besttime = info.array.ctime;
 981                         }
 982                         ss->free_super(st);
 983                 }
 984         }
 985         if (bestsuper != -1) {
 986                 int rv;
 987                 memset(st, 0, sizeof(*st));
 988                 rv = superlist[bestsuper]->load_super(st, fd, NULL);
 989                 if (rv == 0) {
 990                         superlist[bestsuper]->free_super(st);
 991                         return st;
 992                 }
 993         }
 994         free(st);
 995         return NULL;
 996 }
 997
 998 /* Return size of device in bytes */
 999 int get_dev_size(int fd, char *dname, unsigned long long *sizep)
1000 {
1001         unsigned long long ldsize;
1002         struct stat st;
1003
1004         if (fstat(fd, &st) != -1 && S_ISREG(st.st_mode))
1005                 ldsize = (unsigned long long)st.st_size;
1006         else
1007 #ifdef BLKGETSIZE64
1008         if (ioctl(fd, BLKGETSIZE64, &ldsize) != 0)
1009 #endif
1010         {
1011                 unsigned long dsize;
1012                 if (ioctl(fd, BLKGETSIZE, &dsize) == 0) {
1013                         ldsize = dsize;
1014                         ldsize <<= 9;
1015                 } else {
1016                         if (dname)
1017                                 fprintf(stderr, Name ": Cannot get size of %s: %s\b",
1018                                         dname, strerror(errno));
1019                         return 0;
1020                 }
1021         }
1022         *sizep = ldsize;
1023         return 1;
1024 }
1025
1026 void get_one_disk(int mdfd, mdu_array_info_t *ainf, mdu_disk_info_t *disk)
1027 {
1028         int d;
1029         ioctl(mdfd, GET_ARRAY_INFO, ainf);
1030         for (d = 0 ; d < ainf->raid_disks + ainf->nr_disks ; d++)
1031                 if (ioctl(mdfd, GET_DISK_INFO, disk) == 0)
1032                         return;
1033 }
1034
1035 int open_container(int fd)
1036 {
1037         /* 'fd' is a block device.  Find out if it is in use
1038          * by a container, and return an open fd on that container.
1039          */
1040         char path[256];
1041         char *e;
1042         DIR *dir;
1043         struct dirent *de;
1044         int dfd, n;
1045         char buf[200];
1046         int major, minor;
1047         struct stat st;
1048
1049         if (fstat(fd, &st) != 0)
1050                 return -1;
1051         sprintf(path, "/sys/dev/block/%d:%d/holders",
1052                 (int)major(st.st_rdev), (int)minor(st.st_rdev));
1053         e = path + strlen(path);
1054
1055         dir = opendir(path);
1056         if (!dir)
1057                 return -1;
1058         while ((de = readdir(dir))) {
1059                 if (de->d_ino == 0)
1060                         continue;
1061                 if (de->d_name[0] == '.')
1062                         continue;
1063                 sprintf(e, "/%s/dev", de->d_name);
1064                 dfd = open(path, O_RDONLY);
1065                 if (dfd < 0)
1066                         continue;
1067                 n = read(dfd, buf, sizeof(buf));
1068                 close(dfd);
1069                 if (n <= 0 || n >= sizeof(buf))
1070                         continue;
1071                 buf[n] = 0;
1072                 if (sscanf(buf, "%d:%d", &major, &minor) != 2)
1073                         continue;
1074                 sprintf(buf, "%d:%d", major, minor);
1075                 dfd = dev_open(buf, O_RDONLY);
1076                 if (dfd >= 0) {
1077                         closedir(dir);
1078                         return dfd;
1079                 }
1080         }
1081         closedir(dir);
1082         return -1;
1083 }
1084
1085 int add_disk(int mdfd, struct supertype *st,
1086              struct mdinfo *sra, struct mdinfo *info)
1087 {
1088         /* Add a device to an array, in one of 2 ways. */
1089         int rv;
1090 #ifndef MDASSEMBLE
1091         if (st->ss->external) {
1092                 rv = sysfs_add_disk(sra, info,
1093                                     info->disk.state & (1<<MD_DISK_SYNC));
1094                 if (! rv) {
1095                         struct mdinfo *sd2;
1096                         for (sd2 = sra->devs; sd2; sd2=sd2->next)
1097                                 if (sd2 == info)
1098                                         break;
1099                         if (sd2 == NULL) {
1100                                 sd2 = malloc(sizeof(*sd2));
1101                                 *sd2 = *info;
1102                                 sd2->next = sra->devs;
1103                                 sra->devs = sd2;
1104                         }
1105                 }
1106         } else
1107 #endif
1108                 rv = ioctl(mdfd, ADD_NEW_DISK, &info->disk);
1109         return rv;
1110 }
1111
1112 int set_array_info(int mdfd, struct supertype *st, struct mdinfo *info)
1113 {
1114         /* Initialise kernel's knowledge of array.
1115          * This varies between externally managed arrays
1116          * and older kernels
1117          */
1118         int vers = md_get_version(mdfd);
1119         int rv;
1120
1121 #ifndef MDASSEMBLE
1122         if (st->ss->external)
1123                 rv = sysfs_set_array(info, vers);
1124         else
1125 #endif
1126                 if ((vers % 100) >= 1) { /* can use different versions */
1127                 mdu_array_info_t inf;
1128                 memset(&inf, 0, sizeof(inf));
1129                 inf.major_version = info->array.major_version;
1130                 inf.minor_version = info->array.minor_version;
1131                 rv = ioctl(mdfd, SET_ARRAY_INFO, &inf);
1132         } else
1133                 rv = ioctl(mdfd, SET_ARRAY_INFO, NULL);
1134         return rv;
1135 }
1136
1137 char *devnum2devname(int num)
1138 {
1139         char name[100];
1140         if (num > 0)
1141                 sprintf(name, "md%d", num);
1142         else
1143                 sprintf(name, "md_d%d", -1-num);
1144         return strdup(name);
1145 }
1146
1147 int devname2devnum(char *name)
1148 {
1149         char *ep;
1150         int num;
1151         if (strncmp(name, "md_d", 4)==0)
1152                 num = -1-strtoul(name+4, &ep, 10);
1153         else
1154                 num = strtoul(name+2, &ep, 10);
1155         return num;
1156 }
1157
1158 int stat2devnum(struct stat *st)
1159 {
1160         char path[30];
1161         char link[200];
1162         char *cp;
1163         int n;
1164
1165         if ((S_IFMT & st->st_mode) == S_IFBLK) {
1166                 if (major(st->st_rdev) == MD_MAJOR)
1167                         return minor(st->st_rdev);
1168                 else if (major(st->st_rdev) == get_mdp_major())
1169                         return -1- (minor(st->st_rdev)>>MdpMinorShift);
1170
1171                 /* must be an extended-minor partition. Look at the
1172                  * /sys/dev/block/%d:%d link which must look like
1173                  * ../../block/mdXXX/mdXXXpYY
1174                  */
1175                 sprintf(path, "/sys/dev/block/%d:%d", major(st->st_rdev),
1176                         minor(st->st_rdev));
1177                 n = readlink(path, link, sizeof(link)-1);
1178                 if (n <= 0)
1179                         return NoMdDev;
1180                 link[n] = 0;
1181                 cp = strrchr(link, '/');
1182                 if (cp) *cp = 0;
1183                 cp = strchr(link, '/');
1184                 if (cp && strncmp(cp, "/md", 3) == 0)
1185                         return devname2devnum(cp+1);
1186         }
1187         return NoMdDev;
1188
1189 }
1190
1191 int fd2devnum(int fd)
1192 {
1193         struct stat stb;
1194         if (fstat(fd, &stb) == 0)
1195                 return stat2devnum(&stb);
1196         return NoMdDev;
1197 }
1198
1199 int mdmon_running(int devnum)
1200 {
1201         char path[100];
1202         char pid[10];
1203         int fd;
1204         int n;
1205         sprintf(path, "/var/run/mdadm/%s.pid", devnum2devname(devnum));
1206         fd = open(path, O_RDONLY, 0);
1207
1208         if (fd < 0)
1209                 return 0;
1210         n = read(fd, pid, 9);
1211         close(fd);
1212         if (n <= 0)
1213                 return 0;
1214         if (kill(atoi(pid), 0) == 0)
1215                 return 1;
1216         return 0;
1217 }
1218
1219 int signal_mdmon(int devnum)
1220 {
1221         char path[100];
1222         char pid[10];
1223         int fd;
1224         int n;
1225         sprintf(path, "/var/run/mdadm/%s.pid", devnum2devname(devnum));
1226         fd = open(path, O_RDONLY, 0);
1227
1228         if (fd < 0)
1229                 return 0;
1230         n = read(fd, pid, 9);
1231         close(fd);
1232         if (n <= 0)
1233                 return 0;
1234         if (kill(atoi(pid), SIGUSR1) == 0)
1235                 return 1;
1236         return 0;
1237 }
1238
1239 int start_mdmon(int devnum)
1240 {
1241         int i;
1242         int len;
1243         pid_t pid;
1244         int status;
1245         char pathbuf[1024];
1246         char *paths[4] = {
1247                 pathbuf,
1248                 "/sbin/mdmon",
1249                 "mdmon",
1250                 NULL
1251         };
1252
1253         if (check_env("MDADM_NO_MDMON"))
1254                 return 0;
1255
1256         len = readlink("/proc/self/exe", pathbuf, sizeof(pathbuf));
1257         if (len > 0) {
1258                 char *sl;
1259                 pathbuf[len] = 0;
1260                 sl = strrchr(pathbuf, '/');
1261                 if (sl)
1262                         sl++;
1263                 else
1264                         sl = pathbuf;
1265                 strcpy(sl, "mdmon");
1266         } else
1267                 pathbuf[0] = '\0';
1268
1269         switch(fork()) {
1270         case 0:
1271                 /* FIXME yuk. CLOSE_EXEC?? */
1272                 for (i=3; i < 100; i++)
1273                         close(i);
1274                 for (i=0; paths[i]; i++)
1275                         if (paths[i][0])
1276                                 execl(paths[i], "mdmon",
1277                                       devnum2devname(devnum),
1278                                       NULL);
1279                 exit(1);
1280         case -1: fprintf(stderr, Name ": cannot run mdmon. "
1281                          "Array remains readonly\n");
1282                 return -1;
1283         default: /* parent - good */
1284                 pid = wait(&status);
1285                 if (pid < 0 || status != 0)
1286                         return -1;
1287         }
1288         return 0;
1289 }
1290
1291 int check_env(char *name)
1292 {
1293         char *val = getenv(name);
1294
1295         if (val && atoi(val) == 1)
1296                 return 1;
1297
1298         return 0;
1299 }
1300
1301 #ifndef MDASSEMBLE
1302 int flush_metadata_updates(struct supertype *st)
1303 {
1304         int sfd;
1305         if (!st->updates) {
1306                 st->update_tail = NULL;
1307                 return -1;
1308         }
1309
1310         sfd = connect_monitor(devnum2devname(st->container_dev));
1311         if (sfd < 0)
1312                 return -1;
1313
1314         while (st->updates) {
1315                 struct metadata_update *mu = st->updates;
1316                 st->updates = mu->next;
1317
1318                 send_message(sfd, mu, 0);
1319                 wait_reply(sfd, 0);
1320                 free(mu->buf);
1321                 free(mu);
1322         }
1323         ack(sfd, 0);
1324         wait_reply(sfd, 0);
1325         close(sfd);
1326         st->update_tail = NULL;
1327         return 0;
1328 }
1329
1330 void append_metadata_update(struct supertype *st, void *buf, int len)
1331 {
1332
1333         struct metadata_update *mu = malloc(sizeof(*mu));
1334
1335         mu->buf = buf;
1336         mu->len = len;
1337         mu->space = NULL;
1338         mu->next = NULL;
1339         *st->update_tail = mu;
1340         st->update_tail = &mu->next;
1341 }
1342 #endif /* MDASSEMBLE */
1343
1344 #ifdef __TINYC__
1345 /* tinyc doesn't optimize this check in ioctl.h out ... */
1346 unsigned int __invalid_size_argument_for_IOC = 0;
1347 #endif
1348