util.c

   1 /*
   2  * mdadm - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001-2006 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@cse.unsw.edu.au>
  23  *    Paper: Neil Brown
  24  *           School of Computer Science and Engineering
  25  *           The University of New South Wales
  26  *           Sydney, 2052
  27  *           Australia
  28  */
  29
  30 #include        "mdadm.h"
  31 #include        "md_p.h"
  32 #include        <sys/socket.h>
  33 #include        <sys/utsname.h>
  34 #include        <sys/wait.h>
  35 #include        <sys/un.h>
  36 #include        <ctype.h>
  37 #include        <dirent.h>
  38 #include        <signal.h>
  39
  40 /*
  41  * following taken from linux/blkpg.h because they aren't
  42  * anywhere else and it isn't safe to #include linux/ * stuff.
  43  */
  44
  45 #define BLKPG      _IO(0x12,105)
  46
  47 /* The argument structure */
  48 struct blkpg_ioctl_arg {
  49         int op;
  50         int flags;
  51         int datalen;
  52         void *data;
  53 };
  54
  55 /* The subfunctions (for the op field) */
  56 #define BLKPG_ADD_PARTITION     1
  57 #define BLKPG_DEL_PARTITION     2
  58
  59 /* Sizes of name fields. Unused at present. */
  60 #define BLKPG_DEVNAMELTH        64
  61 #define BLKPG_VOLNAMELTH        64
  62
  63 /* The data structure for ADD_PARTITION and DEL_PARTITION */
  64 struct blkpg_partition {
  65         long long start;                /* starting offset in bytes */
  66         long long length;               /* length in bytes */
  67         int pno;                        /* partition number */
  68         char devname[BLKPG_DEVNAMELTH]; /* partition name, like sda5 or c0d1p2,
  69                                            to be used in kernel messages */
  70         char volname[BLKPG_VOLNAMELTH]; /* volume label */
  71 };
  72
  73 /*
  74  * Parse a 128 bit uuid in 4 integers
  75  * format is 32 hexx nibbles with options :.<space> separator
  76  * If not exactly 32 hex digits are found, return 0
  77  * else return 1
  78  */
  79 int parse_uuid(char *str, int uuid[4])
  80 {
  81         int hit = 0; /* number of Hex digIT */
  82         int i;
  83         char c;
  84         for (i=0; i<4; i++) uuid[i]=0;
  85
  86         while ((c= *str++)) {
  87                 int n;
  88                 if (c>='0' && c<='9')
  89                         n = c-'0';
  90                 else if (c>='a' && c <= 'f')
  91                         n = 10 + c - 'a';
  92                 else if (c>='A' && c <= 'F')
  93                         n = 10 + c - 'A';
  94                 else if (strchr(":. -", c))
  95                         continue;
  96                 else return 0;
  97
  98                 if (hit<32) {
  99                         uuid[hit/8] <<= 4;
 100                         uuid[hit/8] += n;
 101                 }
 102                 hit++;
 103         }
 104         if (hit == 32)
 105                 return 1;
 106         return 0;
 107 }
 108
 109
 110 /*
 111  * Get the md version number.
 112  * We use the RAID_VERSION ioctl if it is supported
 113  * If not, but we have a block device with major '9', we assume
 114  * 0.36.0
 115  *
 116  * Return version number as 24 but number - assume version parts
 117  * always < 255
 118  */
 119
 120 int md_get_version(int fd)
 121 {
 122     struct stat stb;
 123     mdu_version_t vers;
 124
 125     if (fstat(fd, &stb)<0)
 126         return -1;
 127     if ((S_IFMT&stb.st_mode) != S_IFBLK)
 128         return -1;
 129
 130     if (ioctl(fd, RAID_VERSION, &vers) == 0)
 131         return  (vers.major*10000) + (vers.minor*100) + vers.patchlevel;
 132     if (errno == EACCES)
 133             return -1;
 134     if (major(stb.st_rdev) == MD_MAJOR)
 135         return (3600);
 136     return -1;
 137 }
 138
 139 int get_linux_version()
 140 {
 141         struct utsname name;
 142         char *cp;
 143         int a,b,c;
 144         if (uname(&name) <0)
 145                 return -1;
 146
 147         cp = name.release;
 148         a = strtoul(cp, &cp, 10);
 149         if (*cp != '.') return -1;
 150         b = strtoul(cp+1, &cp, 10);
 151         if (*cp != '.') return -1;
 152         c = strtoul(cp+1, NULL, 10);
 153
 154         return (a*1000000)+(b*1000)+c;
 155 }
 156
 157 void remove_partitions(int fd)
 158 {
 159         /* remove partitions from this block devices.
 160          * This is used for components added to an array
 161          */
 162 #ifdef BLKPG_DEL_PARTITION
 163         struct blkpg_ioctl_arg a;
 164         struct blkpg_partition p;
 165
 166         a.op = BLKPG_DEL_PARTITION;
 167         a.data = (void*)&p;
 168         a.datalen = sizeof(p);
 169         a.flags = 0;
 170         memset(a.data, 0, a.datalen);
 171         for (p.pno=0; p.pno < 16; p.pno++)
 172                 ioctl(fd, BLKPG, &a);
 173 #endif
 174 }
 175
 176 int enough(int level, int raid_disks, int layout, int clean,
 177            char *avail, int avail_disks)
 178 {
 179         int copies, first;
 180         switch (level) {
 181         case 10:
 182                 /* This is the tricky one - we need to check
 183                  * which actual disks are present.
 184                  */
 185                 copies = (layout&255)* ((layout>>8) & 255);
 186                 first=0;
 187                 do {
 188                         /* there must be one of the 'copies' form 'first' */
 189                         int n = copies;
 190                         int cnt=0;
 191                         while (n--) {
 192                                 if (avail[first])
 193                                         cnt++;
 194                                 first = (first+1) % raid_disks;
 195                         }
 196                         if (cnt == 0)
 197                                 return 0;
 198
 199                 } while (first != 0);
 200                 return 1;
 201
 202         case -4:
 203                 return avail_disks>= 1;
 204         case -1:
 205         case 0:
 206                 return avail_disks == raid_disks;
 207         case 1:
 208                 return avail_disks >= 1;
 209         case 4:
 210         case 5:
 211                 if (clean)
 212                         return avail_disks >= raid_disks-1;
 213                 else
 214                         return avail_disks >= raid_disks;
 215         case 6:
 216                 if (clean)
 217                         return avail_disks >= raid_disks-2;
 218                 else
 219                         return avail_disks >= raid_disks;
 220         default:
 221                 return 0;
 222         }
 223 }
 224
 225 int same_uuid(int a[4], int b[4], int swapuuid)
 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 #ifndef MDASSEMBLE
 273 int check_ext2(int fd, char *name)
 274 {
 275         /*
 276          * Check for an ext2fs file system.
 277          * Superblock is always 1K at 1K offset
 278          *
 279          * s_magic is le16 at 56 == 0xEF53
 280          * report mtime - le32 at 44
 281          * blocks - le32 at 4
 282          * logblksize - le32 at 24
 283          */
 284         unsigned char sb[1024];
 285         time_t mtime;
 286         int size, bsize;
 287         if (lseek(fd, 1024,0)!= 1024)
 288                 return 0;
 289         if (read(fd, sb, 1024)!= 1024)
 290                 return 0;
 291         if (sb[56] != 0x53 || sb[57] != 0xef)
 292                 return 0;
 293
 294         mtime = sb[44]|(sb[45]|(sb[46]|sb[47]<<8)<<8)<<8;
 295         bsize = sb[24]|(sb[25]|(sb[26]|sb[27]<<8)<<8)<<8;
 296         size = sb[4]|(sb[5]|(sb[6]|sb[7]<<8)<<8)<<8;
 297         fprintf(stderr, Name ": %s appears to contain an ext2fs file system\n",
 298                 name);
 299         fprintf(stderr,"    size=%dK  mtime=%s",
 300                 size*(1<<bsize), ctime(&mtime));
 301         return 1;
 302 }
 303
 304 int check_reiser(int fd, char *name)
 305 {
 306         /*
 307          * superblock is at 64K
 308          * size is 1024;
 309          * Magic string "ReIsErFs" or "ReIsEr2Fs" at 52
 310          *
 311          */
 312         unsigned char sb[1024];
 313         unsigned long size;
 314         if (lseek(fd, 64*1024, 0) != 64*1024)
 315                 return 0;
 316         if (read(fd, sb, 1024) != 1024)
 317                 return 0;
 318         if (strncmp((char*)sb+52, "ReIsErFs",8)!=0 &&
 319             strncmp((char*)sb+52, "ReIsEr2Fs",9)!=0)
 320                 return 0;
 321         fprintf(stderr, Name ": %s appears to contain a reiserfs file system\n",name);
 322         size = sb[0]|(sb[1]|(sb[2]|sb[3]<<8)<<8)<<8;
 323         fprintf(stderr, "    size = %luK\n", size*4);
 324
 325         return 1;
 326 }
 327
 328 int check_raid(int fd, char *name)
 329 {
 330         struct mdinfo info;
 331         time_t crtime;
 332         char *level;
 333         struct supertype *st = guess_super(fd);
 334
 335         if (!st) return 0;
 336         st->ss->load_super(st, fd, name);
 337         /* Looks like a raid array .. */
 338         fprintf(stderr, Name ": %s appears to be part of a raid array:\n",
 339                 name);
 340         st->ss->getinfo_super(st, &info);
 341         st->ss->free_super(st);
 342         crtime = info.array.ctime;
 343         level = map_num(pers, info.array.level);
 344         if (!level) level = "-unknown-";
 345         fprintf(stderr, "    level=%s devices=%d ctime=%s",
 346                 level, info.array.raid_disks, ctime(&crtime));
 347         return 1;
 348 }
 349
 350 int ask(char *mesg)
 351 {
 352         char *add = "";
 353         int i;
 354         for (i=0; i<5; i++) {
 355                 char buf[100];
 356                 fprintf(stderr, "%s%s", mesg, add);
 357                 fflush(stderr);
 358                 if (fgets(buf, 100, stdin)==NULL)
 359                         return 0;
 360                 if (buf[0]=='y' || buf[0]=='Y')
 361                         return 1;
 362                 if (buf[0]=='n' || buf[0]=='N')
 363                         return 0;
 364                 add = "(y/n) ";
 365         }
 366         fprintf(stderr, Name ": assuming 'no'\n");
 367         return 0;
 368 }
 369 #endif /* MDASSEMBLE */
 370
 371 char *map_num(mapping_t *map, int num)
 372 {
 373         while (map->name) {
 374                 if (map->num == num)
 375                         return map->name;
 376                 map++;
 377         }
 378         return NULL;
 379 }
 380
 381 int map_name(mapping_t *map, char *name)
 382 {
 383         while (map->name) {
 384                 if (strcmp(map->name, name)==0)
 385                         return map->num;
 386                 map++;
 387         }
 388         return UnSet;
 389 }
 390
 391
 392 int is_standard(char *dev, int *nump)
 393 {
 394         /* tests if dev is a "standard" md dev name.
 395          * i.e if the last component is "/dNN" or "/mdNN",
 396          * where NN is a string of digits
 397          * Returns 1 if a partitionable standard,
 398          *   -1 if non-partitonable,
 399          *   0 if not a standard name.
 400          */
 401         char *d = strrchr(dev, '/');
 402         int type=0;
 403         int num;
 404         if (!d)
 405                 return 0;
 406         if (strncmp(d, "/d",2)==0)
 407                 d += 2, type=1; /* /dev/md/dN{pM} */
 408         else if (strncmp(d, "/md_d", 5)==0)
 409                 d += 5, type=1; /* /dev/md_dNpM */
 410         else if (strncmp(d, "/md", 3)==0)
 411                 d += 3, type=-1; /* /dev/mdN */
 412         else if (d-dev > 3 && strncmp(d-2, "md/", 3)==0)
 413                 d += 1, type=-1; /* /dev/md/N */
 414         else
 415                 return 0;
 416         if (!*d)
 417                 return 0;
 418         num = atoi(d);
 419         while (isdigit(*d))
 420                 d++;
 421         if (*d)
 422                 return 0;
 423         if (nump) *nump = num;
 424
 425         return type;
 426 }
 427
 428
 429 /*
 430  * convert a major/minor pair for a block device into a name in /dev, if possible.
 431  * On the first call, walk /dev collecting name.
 432  * Put them in a simple linked listfor now.
 433  */
 434 struct devmap {
 435     int major, minor;
 436     char *name;
 437     struct devmap *next;
 438 } *devlist = NULL;
 439 int devlist_ready = 0;
 440
 441 int add_dev(const char *name, const struct stat *stb, int flag, struct FTW *s)
 442 {
 443         struct stat st;
 444         if (S_ISLNK(stb->st_mode)) {
 445                 stat(name, &st);
 446                 stb = &st;
 447         }
 448
 449         if ((stb->st_mode&S_IFMT)== S_IFBLK) {
 450                 char *n = strdup(name);
 451                 struct devmap *dm = malloc(sizeof(*dm));
 452                 if (strncmp(n, "/dev/./", 7)==0)
 453                         strcpy(n+4, name+6);
 454                 if (dm) {
 455                         dm->major = major(stb->st_rdev);
 456                         dm->minor = minor(stb->st_rdev);
 457                         dm->name = n;
 458                         dm->next = devlist;
 459                         devlist = dm;
 460                 }
 461         }
 462         return 0;
 463 }
 464
 465 #ifndef HAVE_NFTW
 466 #ifdef HAVE_FTW
 467 int add_dev_1(const char *name, const struct stat *stb, int flag)
 468 {
 469         return add_dev(name, stb, flag, NULL);
 470 }
 471 int nftw(const char *path, int (*han)(const char *name, const struct stat *stb, int flag, struct FTW *s), int nopenfd, int flags)
 472 {
 473         return ftw(path, add_dev_1, nopenfd);
 474 }
 475 #else
 476 int nftw(const char *path, int (*han)(const char *name, const struct stat *stb, int flag, struct FTW *s), int nopenfd, int flags)
 477 {
 478         return 0;
 479 }
 480 #endif /* HAVE_FTW */
 481 #endif /* HAVE_NFTW */
 482
 483 /*
 484  * Find a block device with the right major/minor number.
 485  * If we find multiple names, choose the shortest.
 486  * If we find a non-standard name, it is probably there
 487  * deliberately so prefer it over a standard name.
 488  * This applies only to names for MD devices.
 489  */
 490 char *map_dev(int major, int minor, int create)
 491 {
 492         struct devmap *p;
 493         char *std = NULL, *nonstd=NULL;
 494         int did_check = 0;
 495
 496         if (major == 0 && minor == 0)
 497                         return NULL;
 498
 499  retry:
 500         if (!devlist_ready) {
 501                 char *dev = "/dev";
 502                 struct stat stb;
 503                 while(devlist) {
 504                         struct devmap *d = devlist;
 505                         devlist = d->next;
 506                         free(d->name);
 507                         free(d);
 508                 }
 509                 if (lstat(dev, &stb)==0 &&
 510                     S_ISLNK(stb.st_mode))
 511                         dev = "/dev/.";
 512                 nftw(dev, add_dev, 10, FTW_PHYS);
 513                 devlist_ready=1;
 514                 did_check = 1;
 515         }
 516
 517         for (p=devlist; p; p=p->next)
 518                 if (p->major == major &&
 519                     p->minor == minor) {
 520                         if (is_standard(p->name, NULL)) {
 521                                 if (std == NULL ||
 522                                     strlen(p->name) < strlen(std))
 523                                         std = p->name;
 524                         } else {
 525                                 if (nonstd == NULL ||
 526                                     strlen(p->name) < strlen(nonstd))
 527                                         nonstd = p->name;
 528                         }
 529                 }
 530         if (!std && !nonstd && !did_check) {
 531                 devlist_ready = 0;
 532                 goto retry;
 533         }
 534         if (create && !std && !nonstd) {
 535                 static char buf[30];
 536                 snprintf(buf, sizeof(buf), "%d:%d", major, minor);
 537                 nonstd = buf;
 538         }
 539
 540         return nonstd ? nonstd : std;
 541 }
 542
 543 unsigned long calc_csum(void *super, int bytes)
 544 {
 545         unsigned long long newcsum = 0;
 546         int i;
 547         unsigned int csum;
 548         unsigned int *superc = (unsigned int*) super;
 549
 550         for(i=0; i<bytes/4; i++)
 551                 newcsum+= superc[i];
 552         csum = (newcsum& 0xffffffff) + (newcsum>>32);
 553 #ifdef __alpha__
 554 /* The in-kernel checksum calculation is always 16bit on
 555  * the alpha, though it is 32 bit on i386...
 556  * I wonder what it is elsewhere... (it uses and API in
 557  * a way that it shouldn't).
 558  */
 559         csum = (csum & 0xffff) + (csum >> 16);
 560         csum = (csum & 0xffff) + (csum >> 16);
 561 #endif
 562         return csum;
 563 }
 564
 565 #ifndef MDASSEMBLE
 566 char *human_size(long long bytes)
 567 {
 568         static char buf[30];
 569
 570         /* We convert bytes to either centi-M{ega,ibi}bytes or
 571          * centi-G{igi,ibi}bytes, with appropriate rounding,
 572          * and then print 1/100th of those as a decimal.
 573          * We allow upto 2048Megabytes before converting to
 574          * gigabytes, as that shows more precision and isn't
 575          * too large a number.
 576          * Terrabytes are not yet handled.
 577          */
 578
 579         if (bytes < 5000*1024)
 580                 buf[0]=0;
 581         else if (bytes < 2*1024LL*1024LL*1024LL) {
 582                 long cMiB = (bytes / ( (1LL<<20) / 200LL ) +1) /2;
 583                 long cMB  = (bytes / ( 1000000LL / 200LL ) +1) /2;
 584                 snprintf(buf, sizeof(buf), " (%ld.%02ld MiB %ld.%02ld MB)",
 585                         cMiB/100 , cMiB % 100,
 586                         cMB/100, cMB % 100);
 587         } else {
 588                 long cGiB = (bytes / ( (1LL<<30) / 200LL ) +1) /2;
 589                 long cGB  = (bytes / (1000000000LL/200LL ) +1) /2;
 590                 snprintf(buf, sizeof(buf), " (%ld.%02ld GiB %ld.%02ld GB)",
 591                         cGiB/100 , cGiB % 100,
 592                         cGB/100, cGB % 100);
 593         }
 594         return buf;
 595 }
 596
 597 char *human_size_brief(long long bytes)
 598 {
 599         static char buf[30];
 600
 601         if (bytes < 5000*1024)
 602                 snprintf(buf, sizeof(buf), "%ld.%02ldKiB",
 603                         (long)(bytes>>10), (long)(((bytes&1023)*100+512)/1024)
 604                         );
 605         else if (bytes < 2*1024LL*1024LL*1024LL)
 606                 snprintf(buf, sizeof(buf), "%ld.%02ldMiB",
 607                         (long)(bytes>>20),
 608                         (long)((bytes&0xfffff)+0x100000/200)/(0x100000/100)
 609                         );
 610         else
 611                 snprintf(buf, sizeof(buf), "%ld.%02ldGiB",
 612                         (long)(bytes>>30),
 613                         (long)(((bytes>>10)&0xfffff)+0x100000/200)/(0x100000/100)
 614                         );
 615         return buf;
 616 }
 617 #endif
 618
 619 unsigned long long calc_array_size(int level, int raid_disks, int layout,
 620                                    int chunksize, unsigned long long devsize)
 621 {
 622         int data_disks = 0;
 623         switch (level) {
 624         case 0: data_disks = raid_disks; break;
 625         case 1: data_disks = 1; break;
 626         case 4:
 627         case 5: data_disks = raid_disks - 1; break;
 628         case 6: data_disks = raid_disks - 2; break;
 629         case 10: data_disks = raid_disks / (layout & 255) / ((layout>>8)&255);
 630                 break;
 631         }
 632         devsize &= ~(unsigned long long)((chunksize>>9)-1);
 633         return data_disks * devsize;
 634 }
 635
 636 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
 637 int get_mdp_major(void)
 638 {
 639 static int mdp_major = -1;
 640         FILE *fl;
 641         char *w;
 642         int have_block = 0;
 643         int have_devices = 0;
 644         int last_num = -1;
 645
 646         if (mdp_major != -1)
 647                 return mdp_major;
 648         fl = fopen("/proc/devices", "r");
 649         if (!fl)
 650                 return -1;
 651         while ((w = conf_word(fl, 1))) {
 652                 if (have_block && strcmp(w, "devices:")==0)
 653                         have_devices = 1;
 654                 have_block =  (strcmp(w, "Block")==0);
 655                 if (isdigit(w[0]))
 656                         last_num = atoi(w);
 657                 if (have_devices && strcmp(w, "mdp")==0)
 658                         mdp_major = last_num;
 659                 free(w);
 660         }
 661         fclose(fl);
 662         return mdp_major;
 663 }
 664
 665
 666
 667 char *get_md_name(int dev)
 668 {
 669         /* find /dev/md%d or /dev/md/%d or make a device /dev/.tmp.md%d */
 670         /* if dev < 0, want /dev/md/d%d or find mdp in /proc/devices ... */
 671         static char devname[50];
 672         struct stat stb;
 673         dev_t rdev;
 674         char *dn;
 675
 676         if (dev < 0) {
 677                 int mdp =  get_mdp_major();
 678                 if (mdp < 0) return NULL;
 679                 rdev = makedev(mdp, (-1-dev)<<6);
 680                 snprintf(devname, sizeof(devname), "/dev/md/d%d", -1-dev);
 681                 if (stat(devname, &stb) == 0
 682                     && (S_IFMT&stb.st_mode) == S_IFBLK
 683                     && (stb.st_rdev == rdev))
 684                         return devname;
 685         } else {
 686                 rdev = makedev(MD_MAJOR, dev);
 687                 snprintf(devname, sizeof(devname), "/dev/md%d", dev);
 688                 if (stat(devname, &stb) == 0
 689                     && (S_IFMT&stb.st_mode) == S_IFBLK
 690                     && (stb.st_rdev == rdev))
 691                         return devname;
 692
 693                 snprintf(devname, sizeof(devname), "/dev/md/%d", dev);
 694                 if (stat(devname, &stb) == 0
 695                     && (S_IFMT&stb.st_mode) == S_IFBLK
 696                     && (stb.st_rdev == rdev))
 697                         return devname;
 698         }
 699         dn = map_dev(major(rdev), minor(rdev), 0);
 700         if (dn)
 701                 return dn;
 702         snprintf(devname, sizeof(devname), "/dev/.tmp.md%d", dev);
 703         if (mknod(devname, S_IFBLK | 0600, rdev) == -1)
 704                 if (errno != EEXIST)
 705                         return NULL;
 706
 707         if (stat(devname, &stb) == 0
 708             && (S_IFMT&stb.st_mode) == S_IFBLK
 709             && (stb.st_rdev == rdev))
 710                 return devname;
 711         unlink(devname);
 712         return NULL;
 713 }
 714
 715 void put_md_name(char *name)
 716 {
 717         if (strncmp(name, "/dev/.tmp.md", 12)==0)
 718                 unlink(name);
 719 }
 720
 721 int find_free_devnum(int use_partitions)
 722 {
 723         int devnum;
 724         for (devnum = 127; devnum != 128;
 725              devnum = devnum ? devnum-1 : (1<<22)-1) {
 726                 char *dn;
 727                 int _devnum;
 728
 729                 _devnum = use_partitions ? (-1-devnum) : devnum;
 730                 if (mddev_busy(_devnum))
 731                         continue;
 732                 /* make sure it is new to /dev too, at least as a
 733                  * non-standard */
 734                 dn = map_dev(dev2major(_devnum), dev2minor(_devnum), 0);
 735                 if (dn && ! is_standard(dn, NULL))
 736                         continue;
 737                 break;
 738         }
 739         if (devnum == 128)
 740                 return NoMdDev;
 741         return use_partitions ? (-1-devnum) : devnum;
 742 }
 743 #endif /* !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO) */
 744
 745 int dev_open(char *dev, int flags)
 746 {
 747         /* like 'open', but if 'dev' matches %d:%d, create a temp
 748          * block device and open that
 749          */
 750         char *e;
 751         int fd = -1;
 752         char devname[32];
 753         int major;
 754         int minor;
 755
 756         if (!dev) return -1;
 757
 758         major = strtoul(dev, &e, 0);
 759         if (e > dev && *e == ':' && e[1] &&
 760             (minor = strtoul(e+1, &e, 0)) >= 0 &&
 761             *e == 0) {
 762                 snprintf(devname, sizeof(devname), "/dev/.tmp.md.%d:%d:%d",
 763                          (int)getpid(), major, minor);
 764                 if (mknod(devname, S_IFBLK|0600, makedev(major, minor))==0) {
 765                         fd = open(devname, flags|O_DIRECT);
 766                         unlink(devname);
 767                 }
 768         } else
 769                 fd = open(dev, flags|O_DIRECT);
 770         return fd;
 771 }
 772
 773 int open_dev_excl(int devnum)
 774 {
 775         char buf[20];
 776         int i;
 777
 778         sprintf(buf, "%d:%d", dev2major(devnum), dev2minor(devnum));
 779         for (i=0 ; i<25 ; i++) {
 780                 int fd = dev_open(buf, O_RDWR|O_EXCL);
 781                 if (fd >= 0)
 782                         return fd;
 783                 if (errno != EBUSY)
 784                         return fd;
 785                 usleep(200000);
 786         }
 787         return -1;
 788 }
 789
 790 struct superswitch *superlist[] = { &super0, &super1, &super_ddf, &super_imsm, NULL };
 791
 792 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
 793
 794 struct supertype *super_by_fd(int fd)
 795 {
 796         mdu_array_info_t array;
 797         int vers;
 798         int minor;
 799         struct supertype *st = NULL;
 800         struct mdinfo *sra;
 801         char *verstr;
 802         char version[20];
 803         int i;
 804         char *subarray = NULL;
 805
 806         sra = sysfs_read(fd, 0, GET_VERSION);
 807
 808         if (sra) {
 809                 vers = sra->array.major_version;
 810                 minor = sra->array.minor_version;
 811                 verstr = sra->text_version;
 812         } else {
 813                 if (ioctl(fd, GET_ARRAY_INFO, &array))
 814                         array.major_version = array.minor_version = 0;
 815                 vers = array.major_version;
 816                 minor = array.minor_version;
 817                 verstr = "";
 818         }
 819
 820         if (vers != -1) {
 821                 sprintf(version, "%d.%d", vers, minor);
 822                 verstr = version;
 823         }
 824         if (minor == -2 && is_subarray(verstr)) {
 825                 char *dev = verstr+1;
 826                 subarray = strchr(dev, '/');
 827                 int devnum;
 828                 if (subarray)
 829                         *subarray++ = '\0';
 830                 devnum = devname2devnum(dev);
 831                 subarray = strdup(subarray);
 832                 if (sra)
 833                         sysfs_free(sra);
 834                 sra = sysfs_read(-1, devnum, GET_VERSION);
 835                 verstr = sra->text_version ? : "-no-metadata-";
 836         }
 837
 838         for (i = 0; st == NULL && superlist[i] ; i++)
 839                 st = superlist[i]->match_metadata_desc(verstr);
 840
 841         if (sra)
 842                 sysfs_free(sra);
 843         if (st) {
 844                 st->sb = NULL;
 845                 if (subarray) {
 846                         strncpy(st->subarray, subarray, 32);
 847                         st->subarray[31] = 0;
 848                         free(subarray);
 849                 } else
 850                         st->subarray[0] = 0;
 851         }
 852         return st;
 853 }
 854 #endif /* !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO) */
 855
 856
 857 struct supertype *dup_super(struct supertype *orig)
 858 {
 859         struct supertype *st;
 860
 861         if (!orig)
 862                 return orig;
 863         st = malloc(sizeof(*st));
 864         if (!st)
 865                 return st;
 866         memset(st, 0, sizeof(*st));
 867         st->ss = orig->ss;
 868         st->max_devs = orig->max_devs;
 869         st->minor_version = orig->minor_version;
 870         strcpy(st->subarray, orig->subarray);
 871         st->sb = NULL;
 872         st->info = NULL;
 873         return st;
 874 }
 875
 876 struct supertype *guess_super(int fd)
 877 {
 878         /* try each load_super to find the best match,
 879          * and return the best superswitch
 880          */
 881         struct superswitch  *ss;
 882         struct supertype *st;
 883         unsigned long besttime = 0;
 884         int bestsuper = -1;
 885         int i;
 886
 887         st = malloc(sizeof(*st));
 888         for (i=0 ; superlist[i]; i++) {
 889                 int rv;
 890                 ss = superlist[i];
 891                 memset(st, 0, sizeof(*st));
 892                 rv = ss->load_super(st, fd, NULL);
 893                 if (rv == 0) {
 894                         struct mdinfo info;
 895                         st->ss->getinfo_super(st, &info);
 896                         if (bestsuper == -1 ||
 897                             besttime < info.array.ctime) {
 898                                 bestsuper = i;
 899                                 besttime = info.array.ctime;
 900                         }
 901                         ss->free_super(st);
 902                 }
 903         }
 904         if (bestsuper != -1) {
 905                 int rv;
 906                 memset(st, 0, sizeof(*st));
 907                 rv = superlist[bestsuper]->load_super(st, fd, NULL);
 908                 if (rv == 0) {
 909                         superlist[bestsuper]->free_super(st);
 910                         return st;
 911                 }
 912         }
 913         free(st);
 914         return NULL;
 915 }
 916
 917 /* Return size of device in bytes */
 918 int get_dev_size(int fd, char *dname, unsigned long long *sizep)
 919 {
 920         unsigned long long ldsize;
 921         struct stat st;
 922
 923         if (fstat(fd, &st) != -1 && S_ISREG(st.st_mode))
 924                 ldsize = (unsigned long long)st.st_size;
 925         else
 926 #ifdef BLKGETSIZE64
 927         if (ioctl(fd, BLKGETSIZE64, &ldsize) != 0)
 928 #endif
 929         {
 930                 unsigned long dsize;
 931                 if (ioctl(fd, BLKGETSIZE, &dsize) == 0) {
 932                         ldsize = dsize;
 933                         ldsize <<= 9;
 934                 } else {
 935                         if (dname)
 936                                 fprintf(stderr, Name ": Cannot get size of %s: %s\b",
 937                                         dname, strerror(errno));
 938                         return 0;
 939                 }
 940         }
 941         *sizep = ldsize;
 942         return 1;
 943 }
 944
 945 void get_one_disk(int mdfd, mdu_array_info_t *ainf, mdu_disk_info_t *disk)
 946 {
 947         int d;
 948         ioctl(mdfd, GET_ARRAY_INFO, ainf);
 949         for (d = 0 ; d < ainf->raid_disks + ainf->nr_disks ; d++)
 950                 if (ioctl(mdfd, GET_DISK_INFO, disk) == 0)
 951                         return;
 952 }
 953
 954 int open_container(int fd)
 955 {
 956         /* 'fd' is a block device.  Find out if it is in use
 957          * by a container, and return an open fd on that container.
 958          */
 959         char path[256];
 960         char *e;
 961         DIR *dir;
 962         struct dirent *de;
 963         int dfd, n;
 964         char buf[200];
 965         int major, minor;
 966         struct stat st;
 967
 968         if (fstat(fd, &st) != 0)
 969                 return -1;
 970         sprintf(path, "/sys/dev/block/%d:%d/holders",
 971                 (int)major(st.st_rdev), (int)minor(st.st_rdev));
 972         e = path + strlen(path);
 973
 974         dir = opendir(path);
 975         if (!dir)
 976                 return -1;
 977         while ((de = readdir(dir))) {
 978                 if (de->d_ino == 0)
 979                         continue;
 980                 if (de->d_name[0] == '.')
 981                         continue;
 982                 sprintf(e, "/%s/dev", de->d_name);
 983                 dfd = open(path, O_RDONLY);
 984                 if (dfd < 0)
 985                         continue;
 986                 n = read(dfd, buf, sizeof(buf));
 987                 close(dfd);
 988                 if (n <= 0 || n >= sizeof(buf))
 989                         continue;
 990                 buf[n] = 0;
 991                 if (sscanf(buf, "%d:%d", &major, &minor) != 2)
 992                         continue;
 993                 sprintf(buf, "%d:%d", major, minor);
 994                 dfd = dev_open(buf, O_RDONLY);
 995                 if (dfd >= 0) {
 996                         closedir(dir);
 997                         return dfd;
 998                 }
 999         }
1000         closedir(dir);
1001         return -1;
1002 }
1003
1004 char *devnum2devname(int num)
1005 {
1006         char name[100];
1007         if (num > 0)
1008                 sprintf(name, "md%d", num);
1009         else
1010                 sprintf(name, "md_d%d", -1-num);
1011         return strdup(name);
1012 }
1013
1014 int devname2devnum(char *name)
1015 {
1016         char *ep;
1017         int num;
1018         if (strncmp(name, "md_d", 4)==0)
1019                 num = -1-strtoul(name+4, &ep, 10);
1020         else
1021                 num = strtoul(name+2, &ep, 10);
1022         return num;
1023 }
1024
1025 int stat2devnum(struct stat *st)
1026 {
1027         if ((S_IFMT & st->st_mode) == S_IFBLK) {
1028                 if (major(st->st_rdev) == MD_MAJOR)
1029                         return minor(st->st_rdev);
1030                 else
1031                         return -1- (minor(st->st_rdev)>>6);
1032         }
1033         return -1;
1034
1035 }
1036
1037 int fd2devnum(int fd)
1038 {
1039         struct stat stb;
1040         if (fstat(fd, &stb) == 0)
1041                 return stat2devnum(&stb);
1042         return -1;
1043 }
1044
1045 int mdmon_running(int devnum)
1046 {
1047         char path[100];
1048         char pid[10];
1049         int fd;
1050         int n;
1051         sprintf(path, "/var/run/mdadm/%s.pid", devnum2devname(devnum));
1052         fd = open(path, O_RDONLY, 0);
1053
1054         if (fd < 0)
1055                 return 0;
1056         n = read(fd, pid, 9);
1057         close(fd);
1058         if (n <= 0)
1059                 return 0;
1060         if (kill(atoi(pid), 0) == 0)
1061                 return 1;
1062         return 0;
1063 }
1064
1065 int signal_mdmon(int devnum)
1066 {
1067         char path[100];
1068         char pid[10];
1069         int fd;
1070         int n;
1071         sprintf(path, "/var/run/mdadm/%s.pid", devnum2devname(devnum));
1072         fd = open(path, O_RDONLY, 0);
1073
1074         if (fd < 0)
1075                 return 0;
1076         n = read(fd, pid, 9);
1077         close(fd);
1078         if (n <= 0)
1079                 return 0;
1080         if (kill(atoi(pid), SIGUSR1) == 0)
1081                 return 1;
1082         return 0;
1083 }
1084
1085 int start_mdmon(int devnum)
1086 {
1087         int i;
1088         int len;
1089         pid_t pid;
1090         int status;
1091         char pathbuf[1024];
1092         char *paths[4] = {
1093                 pathbuf,
1094                 "/sbin/mdmon",
1095                 "mdmon",
1096                 NULL
1097         };
1098
1099         if (env_no_mdmon())
1100                 return 0;
1101
1102         len = readlink("/proc/self/exe", pathbuf, sizeof(pathbuf));
1103         if (len > 0) {
1104                 char *sl;
1105                 pathbuf[len] = 0;
1106                 sl = strrchr(pathbuf, '/');
1107                 if (sl)
1108                         sl++;
1109                 else
1110                         sl = pathbuf;
1111                 strcpy(sl, "mdmon");
1112         } else
1113                 pathbuf[0] = '\0';
1114
1115         switch(fork()) {
1116         case 0:
1117                 /* FIXME yuk. CLOSE_EXEC?? */
1118                 for (i=3; i < 100; i++)
1119                         close(i);
1120                 for (i=0; paths[i]; i++)
1121                         if (paths[i][0])
1122                                 execl(paths[i], "mdmon",
1123                                       map_dev(dev2major(devnum),
1124                                               dev2minor(devnum),
1125                                               1), NULL);
1126                 exit(1);
1127         case -1: fprintf(stderr, Name ": cannot run mdmon. "
1128                          "Array remains readonly\n");
1129                 return -1;
1130         default: /* parent - good */
1131                 pid = wait(&status);
1132                 if (pid < 0 || status != 0)
1133                         return -1;
1134         }
1135         return 0;
1136 }
1137
1138 int env_no_mdmon(void)
1139 {
1140         char *val = getenv("MDADM_NO_MDMON");
1141
1142         if (val && atoi(val) == 1)
1143                 return 1;
1144
1145         return 0;
1146 }
1147
1148
1149 int flush_metadata_updates(struct supertype *st)
1150 {
1151         int sfd;
1152         if (!st->updates) {
1153                 st->update_tail = NULL;
1154                 return -1;
1155         }
1156
1157         sfd = connect_monitor(devnum2devname(st->container_dev));
1158         if (sfd < 0)
1159                 return -1;
1160
1161         while (st->updates) {
1162                 struct metadata_update *mu = st->updates;
1163                 st->updates = mu->next;
1164
1165                 send_message(sfd, mu, 0);
1166                 wait_reply(sfd, 0);
1167                 free(mu->buf);
1168                 free(mu);
1169         }
1170         ack(sfd, 0);
1171         wait_reply(sfd, 0);
1172         close(sfd);
1173         st->update_tail = NULL;
1174         return 0;
1175 }
1176
1177 void append_metadata_update(struct supertype *st, void *buf, int len)
1178 {
1179
1180         struct metadata_update *mu = malloc(sizeof(*mu));
1181
1182         mu->buf = buf;
1183         mu->len = len;
1184         mu->space = NULL;
1185         mu->next = NULL;
1186         *st->update_tail = mu;
1187         st->update_tail = &mu->next;
1188 }
1189
1190
1191 #ifdef __TINYC__
1192 /* tinyc doesn't optimize this check in ioctl.h out ... */
1193 unsigned int __invalid_size_argument_for_IOC = 0;
1194 #endif
1195